What is cyclosporine? How does it interact with other drugs?

Grapefruit Juice

Effect: Possible Harmful Interaction

Grapefruit juice slows the body’s normal breakdown of several drugs, including cyclosporine, allowing it to build up to potentially excessive levels in the blood. A study indicates this effect can last for three days or more following the last glass of juice. If one takes cyclosporine, the safest approach is to avoid grapefruit juice altogether.

Citrus Aurantium

Effect: Possible Harmful Interaction

Like grapefruit juice, bitter orange (citrus
aurantium) may raise levels of cyclosporine. If one takes
cyclosporine, the safest approach is to avoid citrus aurantium altogether.

Berberine

Effect: Possible Harmful Interaction

The substance berberine, found in goldenseal, Oregon grape, and barberry, may increase levels of cyclosporine.

St. John’s Wort

Effect: Possible Harmful Interaction

The herb St.
John’s wort (Hypericum perforatum) is
primarily used to treat mild to moderate depression.
St. John’s wort has the potential to accelerate the body’s normal breakdown of
certain drugs, including cyclosporine, resulting in lower blood levels of these
drugs.

This interaction appears to have occurred in two heart transplant patients taking cyclosporine, leading to heart transplant rejection. These persons had been doing well after transplantation while taking standard immunosuppressive therapy that included cyclosporine. After starting St. John’s wort for depression, however, they began experiencing problems and their blood levels of cyclosporine were found to have dipped below the therapeutic range. After St. John’s wort was discontinued, cyclosporine levels returned to normal and no further episodes of rejection occurred.

Numerous cases of transplant rejection episodes involving the heart, kidney, and liver have also been reported in people using the herb. Based on this evidence, if one is taking cyclosporine, one should not take St. John’s wort.

Ipriflavone

Effect: Possible Harmful Interaction

The supplement ipriflavone is used to treat osteoporosis.
A three-year, double-blind trial of almost five hundred women, as well as a small
study, found worrisome evidence that ipriflavone can reduce white blood cell count
in some people. For this reason, anyone taking medications that suppress the
immune system should avoid taking ipriflavone.

Peppermint

Effect: Possible Harmful Interaction

An animal study indicates that use of peppermint oil may increase cyclosporine levels in the body. If one is taking cyclosporine and wishes to use peppermint oil as well, notify a physician in advance, so that blood levels of cyclosporine can be monitored and the dose adjusted if necessary. If one is already taking both peppermint oil and cyclosporine and stops taking the peppermint, the body’s cyclosporine levels may fall. Again, consult a physician to make the necessary dosage adjustment.

Scutellaria baicalensis

Effect: Possible Harmful Interaction

The herb Scutellaria baicalensis (Chinese
skullcap) may impair absorption of cyclosporine, according to
a study in animals.

Bibliography

Alexandersen, P., et al. “Ipriflavone in the Treatment of Postmenopausal Osteoporosis.” Journal of the American Medical Association 285 (2001): 1482-1488.

Barone, G. W., et al. “Drug Interaction Between St. John’s Wort and Cyclosporine.” Annals of Pharmacotherapy 34 (2000): 1013-1016.

Breidenbach, T., et al. “Drug Interaction of St. John’s Wort with Cyclosporin.” The Lancet 355 (2000): 1912.

Ernst, E. “Second Thoughts About Safety of St. John’s Wort.” The Lancet 354 (1999): 2014-2016.

Malhotra, S., et al. “Seville Orange Juice-Felodipine Interaction: Comparison with Dilute Grapefruit Juice and Involvement of Furocoumarins.” Clinical Pharmacology and Therapeutics 69 (2001): 14-23.

Ruschitzka, F., et al. “Acute Heart Transplant Rejection Due to Saint John’s Wort.” The Lancet 355 (2000): 548-549.

Takanaga, H., et al. “Relationship Between Time After Intake of Grapefruit Juice and the Effect on Pharmacokinetics and Pharmacodynamics of Nisoldipine in Healthy Subjects.” Clinical Pharmacology and Therapeutics 67 (2000): 201-214.

Wu, X., et al. “Effects of Berberine on the Blood Concentration of Cyclosporin in Renal Transplanted Recipients: Clinical and Pharmacokinetic Study.” European Journal of Clinical Pharmacology 8 (2005): 567-572.

According to Dr. King in his "I Have a Dream" speech, what is tragic about the Emancipation Proclamation? What connection does he make?

In his “I Have a Dream” speech, Dr. Martin Luther King, Jr. does not actually say that there is anything tragic about the Emancipation Proclamation.  However, we can infer that he does actually think there is something tragic.  The tragic aspect of the Emancipation Proclamation, we can infer, is that it did not actually make African Americans free.

At the beginning of the speech, King mentions the Emancipation Proclamation.  He says that it was a...

In his “I Have a Dream” speech, Dr. Martin Luther King, Jr. does not actually say that there is anything tragic about the Emancipation Proclamation.  However, we can infer that he does actually think there is something tragic.  The tragic aspect of the Emancipation Proclamation, we can infer, is that it did not actually make African Americans free.

At the beginning of the speech, King mentions the Emancipation Proclamation.  He says that it was a “great beacon of light.”  He says that, for African Americans, it represented “a joyous daybreak to end the long night of their captivity.”  In other words the Emancipation Proclamation was a great moment in African American history because it represented the end of slavery.  It meant that African Americans would now (ostensibly) be free.

This is what made the Emancipation Proclamation tragic.  It was supposed to make African Americans free but, about 100 years later, “the Negro is still not free.”  King connects the Proclamation to segregation and discrimination.  He says that segregation and discrimination meant that the promise of the Proclamation had not been fulfilled.  It was tragic that Lincoln’s great Proclamation had not ended up doing what it was supposed to do and that, therefore, African Americans were still in a position of subjugation in the United States.

What are independent, dependent, and control variables in experimentation?

Introduction

Psychology is typically defined as the science of behavior and cognition and is considered a research-oriented discipline, not unlike biology, chemistry, and physics. To appreciate the role of experimentation in psychology, it is useful to view it in the context of the general scientific method employed by psychologists in conducting their research. This scientific method may be described as a four-step sequence starting with identifying a problem and forming a hypothesis. The problem must be one suitable for scientific inquiry—that is, questions concerning values, such as whether rural life is “better” than city life, are more appropriate for philosophical debate than scientific investigation. Questions better suited to the scientific method are those that can be answered through the objective collection of facts—for example, “Are children who are neglected by their parents more likely to do poorly in school than children who are well treated?” The hypothesis is the tentative guess, or the prediction regarding the question’s answer, and is based on other relevant research and existing theory. The second step, and the one with which this article is primarily concerned, is the collection of data (facts) to test the accuracy of the hypothesis. Any one of a number of methods might be employed, including simple observation, survey, or experimentation. The third step is to make sense of the facts that have been accumulated by subjecting them to careful analysis; the fourth step is to share any significant findings with the scientific community.

Research Approaches

In considering step two, the collection of data, it seems that people often mistakenly use the words research and
experiment
interchangeably. A student might ask whether an experiment has been done on a particular topic when, in fact, the student really wants to know if any kind of research has been conducted in that area. All experiments are examples of research, but not all research is experimental. Research that is nonexperimental in nature might be either descriptive or correlational.

Descriptive research is nearly self-explanatory; it occurs when the researcher wants merely to characterize the behaviors of an individual or, more likely, a group. For example, one might want to survey the students of a high school to ascertain the level of alcohol use (alcohol use might be described in terms of average ounces consumed per student per week). One might also spend considerable time observing individuals who have a particular condition, such as infantile autism. A thorough description of their typical behaviors could be useful for someone investigating the cause of this disorder. Descriptive research can be extremely valuable, but it is not useful when researchers want to investigate the relationship between two or more variables (things that vary or quantities that may have different values).

In a correlational study, the researcher measures how strongly the variables are related or the degree to which one variable predicts another variable. A researcher who is interested in the relationship between exposure to violence on television (variable one) and aggressive behavior (variable two) in a group of elementary school children could administer a survey asking the children how much violent television they view and then rank the subjects from high to low levels of this variable. The researcher could similarly interview the school staff and rank the children according to their aggressive behavior. A statistic called a correlation coefficient might then be computed, revealing how the two variables are related and the strength of that relationship.

Cause and Effect

Correlational studies are not uncommon in psychological research. Often, however, a researcher wants even more specific information about the relationships among variables—in particular, about whether one variable causes a change in another variable. In such a situation, experimental research is warranted. This drawback of the correlational approach—its inability to establish causal relationships—is worth considering for a moment. In the hypothetical study described above, the researcher may find that viewing considerable television violence predicts high levels of aggressive behavior, yet she cannot conclude that these viewing habits cause the aggressiveness. After all, it is entirely possible that aggressiveness, caused by some unknown factor, prompts a preference for violent television. That is, the causal direction is unknown; viewing television violence may cause aggressiveness, but the inverse (that aggressiveness causes the watching of violent television programs) is also feasible.

As this is a crucial point, one final illustration is warranted. What if, at a certain Rocky Mountain university, a correlational study has established that high levels of snowfall predict low examination scores? One should not conclude that something about the chemical composition of snow impairs the learning process. The correlation may be real and highly predictive, but the causal culprit may be some other factor. Perhaps, as snowfall increases, so does the incidence of illness, and it is this variable that is causally related to exam scores. Maybe, as snowfall increases, the likelihood of students using their study time for skiing also increases.

Experimentation is a powerful research method because it alone can reveal cause-effect relationships. In an experiment, the researcher does not merely measure the naturally occurring relationships between variables for the purpose of predicting one from the other; rather, he or she systematically manipulates the values of one variable and measures the effect, if any, that is produced in a second variable. The variable that is manipulated is known as the independent variable; the other variable, the behavior in question, is called the dependent variable (any change in it depends on the manipulation of the independent variable). Experimental research is characterized by a desire for control on the part of the researcher. Control of the independent variable and control over extraneous variables are both wanted. That is, there is a desire to eliminate or hold constant the factors, known as control variables, other than the independent variable that might influence the dependent variable. If adequate control is achieved, the researcher may be confident that it was, in fact, the manipulation of the independent variable that produced the change in the dependent variable.

Control Groups

Returning to the relationship between television viewing habits and aggressive behavior in children, suppose that correlational evidence indicates that high levels of the former variable predict high levels of the latter. Now the researcher wants to test the hypothesis that there is a cause-effect relationship between the two variables. She decides to manipulate exposure to television violence (the independent variable) to see what effect might be produced in the aggressiveness of her subjects (the dependent variable). She might choose two levels of the independent variable and have twenty children watch fifteen minutes of a violent detective show while another twenty children are subjected to thirty minutes of the same show.

If an objective rating of playground aggressiveness later reveals more hostility in the thirty-minute group than in the fifteen-minute group, she still cannot be confident that higher levels of television violence cause higher levels of aggressive behavior. More information is needed, especially with regard to issues of control. To begin with, how does the researcher know that it is the violent content of the program that is promoting aggressiveness? Perhaps it is the case that the more time they spend watching television, regardless of subject matter, the more aggressive children become.

This study needs a control group: a group of subjects identical to the experimental subjects with the exception that they do not experience the independent variable. In fact, two control groups might be employed, one that watches fifteen minutes and another that watches thirty minutes of nonviolent programming. The control groups serve as a basis against which the behavior of the experimental groups can be compared. If it is found that the two control groups aggress to the same extent, and to a lesser extent than the experimental groups, the researcher can be more confident that violent programming promotes relatively higher levels of aggressiveness.

The experimenter also needs to be sure that the children in the thirty-minute experimental group were not naturally more aggressive to begin with. One need not be too concerned with this possibility if one randomly assigns subjects to the experimental and control groups. There are certainly individual differences among subjects in factors such as personality and intelligence, but with random assignment (a technique for creating groups of subjects across which individual differences will be evenly dispersed) one can be reasonably sure that those individual differences are evenly dispersed among the experimental and control groups.

Subject Variables

The experimenter might want to control or hold constant other variables. Perhaps she suspects that age, social class, ethnicity, and gender could also influence the children’s aggressiveness. She might want to make sure that these subject variables are eliminated by either choosing subjects who are alike in these ways or by making sure that the groups are balanced for these factors (for example, equal numbers of boys and girls in each group). There are numerous other extraneous variables that might concern the researcher, including the time of day when the children participate, the length of time between television viewing and the assessment of aggressiveness, the children’s diets, the children’s family structures (single or dual parents, siblings or only child), and the disciplinary styles used in the homes. Resource limitations prevent every extraneous variable from being controlled, yet the more control, the more confident the experimenter can be of the cause-effect relationship between the independent and dependent variables.

Influence of Rewards

One more example of experimental research, this one nonhypothetical, will further illustrate the application of this methodology. In 1973, Mark Lepper, David Greene, and Richard Nisbett tested the hypothesis that when people are offered external rewards for performing activities that are naturally enjoyable, their interest in these activities declines. The participants in the study were nursery school children who had already demonstrated a fondness for coloring with marking pens; this was their preferred activity when given an opportunity for free play. The children were randomly assigned to one of three groups. The first group was told previously that they would receive a “good player award” if they would play with the pens when later given the opportunity. Group two received the same reward but without advance notice; they were surprised by the reward. The last group of children was the control group; they were neither rewarded nor told to expect a reward.

The researchers reasoned that the first group of children, having played with the pens to receive a reward, would now perceive their natural interest in this activity as lower than before the study. Indeed, when all groups were later allowed a free play opportunity, it was observed that the “expected reward” group spent significantly less time than the other groups in this previously enjoyable activity. Lepper and his colleagues, then, experimentally supported their hypothesis and reported evidence that reward causes interest in a previously pleasurable behavior to decline. This research has implications for instructors; they should carefully consider the kinds of behavior they reward (with gold stars, lavish praise, high grades, and so on) as they may, ironically, be producing less of the desired behavior. An academic activity that is enjoyable play for a child may become tedious work when a reward system is attached to it.

Criticisms

Although most would agree that the birth of psychology as a science took place in Leipzig, Germany, in 1879, when Wilhelm Wundt established the first laboratory for studying psychological phenomena, there is no clear record of the first use of experimentation. Regardless, there is no disputing the attraction that this method of research has had for many psychologists, who clearly recognize the usefulness of the experiment in investigating potential causal relationships between variables. Hence, experimentation is employed widely across the subfields of psychology, including developmental, cognitive, physiological, clinical, industrial, and social psychology.

This is not to say that all psychologists are completely satisfied with experimental research. It has been argued that an insidious catch-22 exists in some experimental research that limits its usefulness. The argument goes like this: experimenters are motivated to control rigorously the conditions of their studies and the relevant extraneous variables. To gain such control, they often conduct experiments in a laboratory setting. Therefore, subjects are often observed in an artificial environment, engaged in behaviors that are so controlled as to be unnatural, and they clearly know they are being observed—which may further alter their behavior. Such research is said to be lacking in ecological validity or applicability to “real-life” behavior. It may show how subjects behave in a unique laboratory procedure, but it tells little about psychological phenomena as displayed in everyday life. The catch-22, then, is that experimenters desire control to establish that the independent variable is producing a change in the dependent variable, and the more such control, the better; however, the more control, the more risk that the research may be ecologically invalid.

Field Experiments

Most psychologists are sensitive to issues of ecological validity and take pains to make their laboratory procedures as naturalistic as possible. Additionally, much research is conducted outside the laboratory in what are known as field experiments. In such studies, the subjects are unobtrusively observed (perhaps by a confederate of the researcher who would not attract their notice) in natural settings such as classroom, playground, or workplace. Field experiments, then, represent a compromise in that there is bound to be less control than is obtainable in a laboratory, yet the behaviors observed are likely to be natural. Such naturalistic experimentation is likely to continue to increase in the future.

Although experimentation is only one of many methods available to psychologists, it fills a particular need, and that need is not likely to decline in the foreseeable future. In trying to understand the complex relationships among the many variables that affect the way people think and act, experimentation makes a valuable contribution: It is the one methodology available that can reveal unambiguous cause-effect relationships.

Bibliography

Barber, Theodore Xenophon. Pitfalls in Human Research. New York: Pergamon, 1985. Print.

Carlson, Neil R. Psychology: The Science of Behavior. 6th ed. Boston: Allyn, 2007. Print.

Coolican, Hugh. Research Methods and Statistics in Psychology. 6th ed. New York: Psychology, 2014. Print.

Hearst, Eliot, ed. The First Century of Experimental Psychology. Hillsdale: Erlbaum, 1979. Print.

Schweigert, Wendy A. Research Methods in Psychology: A Handbook. 3rd ed. Long Grove: Waveland, 2012. Print.

Shaughnessy, John J., and Eugene B. Zechmeister. Research Methods in Psychology. 8th ed. New York: McGraw-Hill, 2009. Print.

Stern, Paul C., and Linda Kalof. Evaluating Social Science Research. 2nd ed. New York: Oxford UP, 1996. Print.

Walsh, Richard T. G., Thomas Teo, and Angelina Baydala. A Critical History and Philosophy of Psychology. New York: Cambridge UP, 2014. Print.

What is the concept of leadership in the field of social psychology?

Introduction

Much of the behavior of individuals is shaped and influenced by other people. Someone who has relatively more influence over others—for better or worse—can be called a leader. This influence can arise naturally through personal interactions, or it may be attributed to a structuring of relationships whereby one person is designated as having power over, or responsibility for, the others.

Consideration Versus Initiating Structure

In general, theories of leadership make a distinction between two broad types of behavior. One type, often called consideration, revolves around the leader’s relationship with the group members. The leader who exhibits this type of behavior shows warmth, trust, respect, and concern for the group members. Communication between the leader and the group is two-way, and group members are encouraged to participate in decision making. The second type of leader behavior concerns initiating structure. This construct refers to a direct focus on performance goals. The leader who is high in initiating structure defines roles, assigns tasks, plans work, and pushes for achievement.

Over the years, theorists differed in their views on the optimal mix of consideration and initiating structure in their conceptions of the ideal leader. Those advocating a human-relations approach saw leadership success resulting from high consideration and low initiating structure. Others, however, argued for the intuitive appeal of a leader being high on both dimensions. Research soon revealed that there was no single best combination for every leader in every position.

Contingency Theory

One approach to the study of leadership, Fred Fiedler’s
contingency theory, is founded on the assumption that effective leadership depends on the circumstances. Every leader is assumed to have either a work focus or a worker focus. This is measured by the “least-preferred coworker” scale. By asking people a series of questions about the person with whom they have worked least well, the procedure permits an evaluation of the degree to which one can keep work and relationships separate.

Three characteristics of a situation are deemed important in determining which style will work best. First and most important is the quality of the relations between the leader and members of the group. To assess leader-member relations, a leader is asked to use a five-point scale to indicate extent of agreement or disagreement with statements such as “My subordinates give me a good deal of help and support in getting the job done.” After scoring the leader’s responses to such items, the leader-member relations are characterized as “good” or “poor.”

The second most important feature of a situation is the amount of task structure. A situation is classified as “high” or “low” depending on the leader’s rating of the frequency with which various statements are true. The statements ask whether there is a quantitative evaluation of the task, whether roles are clearly defined, whether there are specific goals, whether it is obvious when the task is finished, and whether formal procedures have been established.

According to contingency theory, the third—and least important—characteristic of a situation is the degree of power inherent in the leader’s position. Position power is assessed by asking questions such as whether the leader can affect the promotion or firing of subordinates and if the leader has the necessary knowledge for assigning tasks to subordinates. As with the other features, there are two types of position power, strong or weak.

In summary, there are eight possible types of situations, according to contingency theory: every possible combination of leader-member relations (good vs. poor), task structure (high vs. low), and position power (strong vs. weak). These eight combinations vary along a continuum from high situational control (good leader-member relations, high task structure, and strong position power) to low situational control (poor leader-member relations, low task structure, and weak position power). Fiedler notes that the match between situation and leader orientation is critical for effective leadership. He recommends an emphasis on task performance in the three situations with the highest situational control and in the one with extremely low situational control. For the remaining four situations, the theory suggests that a group will perform best if the leader has an employee-oriented style and is motivated by relationships rather than by task performance.

Transformational Leaders

Using an alternative perspective, Bernard Bass conceptualizes leadership as a transaction between followers and their leader. He sees most leadership as characterized by recognizing what followers want and trying to see that they get what they want—assuming that the followers’ behavior warrants it. In short, the leader and followers exchange rewards and promises of rewards for the followers’ cooperation. A minority of leaders are able to motivate their followers to accomplish more than they originally expected to accomplish. This type of leader is called “transformational.” A transformational leader
affirms the followers’ beliefs about the values of outcomes; moves followers to consider the interests of the team, organization, or nation above their own self-interests; and raises the level of needs that followers want to satisfy. Among those who may be called transformational leaders are Alfred Sloan, for his reformation of General Motors; Henry Ford, for revolutionizing US industry; and Lee Iacocca, for revitalizing the Chrysler Corporation. Although transformational leadership has been found in a wide variety of settings, the research on its effectiveness has been almost exclusively conducted by Bass and his colleagues.

Gender and Cultural Differences in Leadership

There has been much speculation about the differences between men and women in their leadership abilities. Psychologists examine these differences by performing controlled studies. In two field studies of leadership in the United States Military Academy at West Point, Robert Rice, Debra Instone, and Jerome Adams asked participants (freshmen) in a training program to evaluate their squad leaders (juniors and seniors). The program consisted of two parts. First there was a six-week period of basic training covering military protocol, tradition, and skill (such as weapon use and marching). The second part was a field training program covering combat-oriented tasks (such as fabricating bridges, driving tanks, directing artillery fire, and conducting reconnaissance exercises). About 10 percent of the leaders in each program were women. The participants’ responses on questionnaires showed the men and women to be comparable in terms of their success as leaders and in the nature of their leadership styles. This conclusion is in agreement with the observations of real operational leadership roles at the academy.

Although sex differences in leadership effectiveness appear to be minimal, there appear to be other group characteristics that are important determinants of leadership behavior. For example, in 1981 Frank Heller and Bernhard Wilpert reported different influence styles for managers from different countries. They determined the extent to which senior and subordinate managers involved group members in decisions. At one extreme, managers made decisions without explanation or discussion. At the other extreme of influence, they delegated decisions, giving subordinates complete control. Their data indicated that participation was emphasized in nations such as Sweden and France, but not in Israel. The United States was somewhere in the middle.

Leadership Style Research

Regardless of the extent to which there are differences among various groups of people, it is clear that there remain individual differences in leadership style. What are the implications for attempts to improve leadership effectiveness if there is no single best leadership style for all situations? One approach is to select the leader who exhibits those characteristics that are most appropriate for the situation.

Another approach, promoted by Fiedler and colleagues, is to engineer the situation to match the characteristics of the leader. That is, people cannot change the extent of task performance or employee orientation in their leadership styles, but they can change the characteristics of their situations. The program to accomplish this uses a self-taught learning process. First the person fills out a questionnaire designed to assess leadership style. Then the characteristics of that individual’s situation, leader-member relations, task structure, and position power are measured. Finally, the person is taught to change the situation to mesh with his or her personality. This might involve such tactics as influencing the supervisor to alter position power or redesigning work to modify task structure. A test of this process was conducted by Fiedler and Martin Chemers in 1984 at Sears, Roebuck, and Company. They implemented eight hours of leader-matching training in two of five randomly selected stores. The other stores had equivalent amounts of training discussions. Subsequent rates of the managers on eight performance scales used by Sears showed those who had received the leader-matching training to be superior on every performance dimension.

Assessing Leadership Types

There have been other applications of leadership research that recommend that the leader choose the appropriate behavior. Victor Vroom and Philip Yetton urge leaders to adopt one of four leadership types. The autocratic leader solves the problem independently, with or without information from subordinates. A consultative leader shares the problem with individual subordinates or with the group and obtains ideas and suggestions that may or may not influence the final decision. A group leader shares the problem with an individual, and together they find a mutually agreeable solution, or with a group that produces a consensus solution that the leader implements. A delegatory leader gives the problem to a single subordinate, offering relevant information but not exerting any influence over the subordinate’s decision.

Which of the above four types of leadership is advocated depends on the answers to a series of questions about the need for a quality solution, the amount of information available to the leader and subordinates, the structure of the problem, and attitudes of subordinates. The questions are arranged in a decision tree, so that at each step the leader answers “yes” or “no” and then proceeds to the next step. Vroom has developed a training program based on this model. It has several components. First is an explanation of the theory. Trainees practice using the theory to describe leader behavior and deciding how they would handle various hypothetical situations. Then trainees take part in simulated leadership situations and receive feedback on both their actual behavior and the leader behavior that is prescribed by the theory. Finally, there are small-group discussions about the experience. The goal is for trainees to learn how and when to adopt new leadership patterns. Reactions of participants to the program tend to be highly favorable.

Leader Behavior Research

Concerns about leadership are evident in nearly every aspect of society. Problems such as illiteracy, inferior education, and environmental destruction are routinely attributed to misguided leadership, ineffective leadership, or an absence of leadership. Within organizations, leaders are held accountable for the work of their subordinates and the ultimate success of the organization. Because of its obvious importance, psychologists have pursued the study of leadership with the goal of developing explanations about the factors that contribute to effective leadership.

One popular conception of leadership is that it is a personality trait. If so, people vary in the extent to which they have leadership abilities. It would also be logical to expect that people in positions of leadership will have different personality characteristics from those who are followers. Yet surprisingly, the results of a large number of studies comparing the traits of leaders and followers have revealed only a few systematic differences. For example, those who are in positions of leadership appear to be, on average, slightly more intelligent and self-confident than followers; however, the magnitude of such differences tends to be small, so there is considerable overlap between leaders and followers. One problem in using this evidence to conclude that individual differences in personality determine leadership is that the traits noted may be the result, rather than the cause, of being in a position of leadership. For example, a person who, for whatever reason, is in a position of leadership may become more self-confident.

This research suggests that there are many factors besides personality that determine the ascent to a position of leadership. This is not so surprising if one considers that groups vary in many ways, as do their leadership needs. Thus there is no clear “leadership type” that is consistent across groups. For this reason, psychologists have tended to abandon the study of leadership as a personality characteristic and pursue other approaches. The advent of an emphasis on leader behavior occurred at Ohio State University in the 1950s. Ralph Stogdill, Edwin Fleischman, and others developed the constructs of leader consideration and initiating structure. These constructs have proved to be useful in several theories of leadership and have been important in attempts to improve leader effectiveness, particularly in organizational settings.

In addition to academic settings, applied settings have been important in the history of leadership research. Studies conducted by the oil company Exxon in an attempt to improve leadership effectiveness led to the independent development of the managerial grid by Robert Blake and Jane Mouton. The two important dimensions of leader behavior that emerged from this work are concern for people and concern for production.

Bibliography

Bass, Bernard M. Bass and Stogdill’s Handbook of Leadership. 3d ed. New York: Free Press, 1990. Print.

Bass, Bernard M.. Leadership and Performance Beyond Expectations. New York: Free Press, 1985. Print.

Brady, Chris, and Orrin Woodward. Launching a Leadership Revolution: Mastering the Five Levels of Influence. New York: Business Plus, 2008. Print.

Day, David V., and John Antonakis. The Nature of Leadership. 2d ed. Thousand Oaks: SAGE, 2012.

Kellerman, Barbara. The End of Leadership. New York: Harper Business, 2012. Print.

Kouzes, James M., and Barry Z. Posner. The Leadership Challenge. 4th ed. San Francisco: Jossey, 2008. Print.

Smith, Blanchard B. “The TELOS Program and the Vroom-Yetton Model.” In Crosscurrents in Leadership. Ed. James G. Hunt and Lars L. Larson. Carbondale: Southern Illinois UP, 1979. Print.

Williams, Pat, and Jim Denney. Leadership Excellence. Uhrichsville: Barbour, 2012. Print.

Yukl, Gary A. Leadership in Organizations. 5th ed. Englewood Cliffs: Prentice, 2001. Print.

What is Ewing sarcoma? |

Related conditions:
Primitive neuroectodermal tumor, peripheral primitive neuroectodermal tumor, Askin’s tumor, osteosarcoma

Definition:

Ewing sarcoma is a rare disease involving cancer cells found in bones and soft tissue. It usually occurs in the pelvis, ribs, arm bone (humerus), shoulder blade, or leg bone (femur). It gets its name from James Ewing, who in the 1920s first described the disease as being separate from other known types of cancers such as lymphoma or neuroblastoma. Ewing noticed that this type of cancer responded well to radiation. It belongs to a group of tumors sometimes called the Ewing family of tumors because of the close molecular relationship between these kinds of tumors.

Risk factors: More than 90 percent of people who develop this disease have an unusual rearrangement between chromosomes: A piece of chromosome 11 and a piece of chromosome 22 have switched places (called a gene translocation). However, this translocation is not inherited or passed on genetically, so family members of those affected with Ewing sarcoma have no more risk of developing the cancer than the general population does.

Male teenagers are most often diagnosed with this disease. The cancer is thought to be linked somehow to the rapid growth that occurs during puberty. Whites are more likely to develop this disease than are Asians and African Americans. MedlinePlus reported in 2014 that Ewing sarcoma is ten times as common in Caucasian children as in children of African or Asian descent.

Very rarely, Ewing sarcoma can develop as a secondary tumor in patients who have had radiation therapy for another type of cancer.

Etiology and the disease process: Because this cancer occurs most often during the teenage years, there may be a link between the onset of puberty and early stages of this disease.

Ewing sarcoma usually starts in a bone, though it can start in soft tissue. The most common starting place for these tumors is in the pelvis or in the leg bones. The tumors may then spread to the chest cavity, other bones, bone marrow, lungs, kidneys, or heart when tumor cells enter the bloodstream and travel elsewhere in the body. This disease may also spread to the central nervous system or lymph nodes, but this is much less common.

Incidence: This disease occurs most often in male children and teenagers, mostly between ten and twenty years old. However, female children and teenagers also develop this disease. In the United States, this cancer affects children less than three years of age at a rate of 0.3 per million and teenagers between the ages of fifteen and nineteen at a rate of 4.6 per million. People over the age of twenty-five rarely develop this type of cancer. In 2014 the American Cancer Society estimated that in North America each year about 225 new cases of this cancer are diagnosed in children and teens. These tumors make up about 30 percent of the bone cancers in children; the American Cancer Society reported in 2014 that about 1 percent of all childhood cancers are Ewing sarcoma.

Symptoms: Symptoms of Ewing sarcoma involve pain (which may be worse at night), swelling (especially when the tumor is located in the long bones of the arm or leg), redness, tenderness, stiffness, a mass that grows quickly and may feel warm, or a bone that breaks unexpectedly. Some patients have fever, fatigue, anemia, or weight loss. Numbness, tingling, or paralysis can also be symptoms if the tumor is located near nerves.

Screening and diagnosis: Because this disease is so rare, no screening is recommended. When Ewing sarcoma is suspected, doctors generally use x-rays to determine if there is a suspicious growth. A magnetic resonance imaging (MRI) scan or blood tests also may be helpful in making a diagnosis. If Ewing sarcoma is suspected, two additional tests are used to see if the disease has spread: a computed tomography (CT) scan, which usually includes the lungs to see if the disease has spread there, and a bone scan.

Ewing sarcoma may initially be mistaken for a bone infection (osteomyelitis) or another type of bone cancer (osteosarcoma). A sample of the tumor (biopsy) is necessary to confirm the diagnosis of Ewing sarcoma. A biopsy may be performed with a fine needle, taking only a small sample of the tumor, or by surgery, where all or a large part of the tumor is removed. Sometimes, bone marrow also is biopsied to determine if the disease has spread there.

There is no formal staging for Ewing sarcoma. Gauging the extent of this disease is done by simply determining whether the cancer has spread into other tissues.

Treatment and therapy: Ewing sarcoma is usually a very aggressive disease. By the time of diagnosis, nearly all patients with Ewing sarcoma have some spreading of the disease throughout the body. Most patients are treated with chemotherapy, sometimes before and after surgery, to ensure treatment of any tumors throughout the body.

Surgery or radiation may also be used at the local site of the main tumor if the tumor can be removed without damaging vital organs. Sometimes surgery involves removing bones, which can be replaced or rebuilt with artificial bones or bone grafts. With Ewing sarcoma, radiation therapy usually involves radiation that comes from a machine outside the body rather than from implanted radiation seeds. Radiation therapy can shrink large tumors to alleviate symptoms if the tumor cannot be removed with surgery.

Other types of treatment may include rehabilitation, including occupational or physical therapy. Patients may also need supportive care to help with side effects of chemotherapy, radiation, or surgery. Some patients may benefit from a transplant of blood stem cells or bone marrow.

Diagnosis of Ewing sarcoma usually occurs during the teenage years, sometimes an already turbulent period. Surgery may cause disfigurement during a period of life when looks are very important. Support groups in which teens meet other people with this condition may be especially helpful in dealing with the psychological trauma that this disease can cause.

Generally, patients with Ewing sarcoma benefit from treatment at a children’s hospital or medical center with doctors who have experience treating pediatric cancers.

Prognosis, prevention, and outcomes: The prognosis for patients with this disease depends on how far the disease has spread, the size and location of the main tumor, and how responsive the tumors are to chemotherapy. For patients who at diagnosis show no signs of the spread of the disease and choose an aggressive course of treatment involving chemotherapy, surgery, and radiation, survival rates at five years are 70 to 75 percent (ACS, 2014). However, at diagnosis, at least 15 percent of these patients already have cancer throughout their bodies, generally because symptoms are so vague and nonspecific. These patients have a five-year survival rate of 15 to 30 percent (ACS, 2014). Children under the age of ten, female children and teenagers, those with smaller tumors, and those who have tumors below the elbow or below the calf have the highest survival rates.

People who have had Ewing sarcoma need continual follow-up care. Even if the cancer is treated and its spread stopped, it often develops again in the place where it first arose and tends to spread throughout the body. Health issues may spring up later that are caused by the type of treatment given. These issues may involve heart and lung problems, slowed or decreased growth and development, and problems with sexual development. It is important for a patient who has had this disease to be regularly monitored for these types of concerns.

There is no known way to prevent Ewing sarcoma. However, not everyone with the gene translocation develops this disease. Scientists are investigating why the gene translocation causes the disease only in some people to see if there are ways to block this cancer from forming. Research is also under way to determine new and improved techniques for diagnosing this cancer earlier in the disease process.

Amer. Cancer Soc. "Ewing Family of Tumors." Cancer.org. ACS, 2014. Web. 21 Oct. 2014.

Chen, Yi-Bin. "Ewing Sarcoma." MedlinePlus. US NLM/NIH, 23 Mar. 2014. Web. 21 Oct. 2014.

Machado, Isidro, et al. "Biomarkers in the Ewing Sarcoma Family of Tumors." Current Biomarker Findings 4 (2014): 81–91. Digital file.

Natl. Cancer Inst. "Ewing Sarcoma Treatment (PDQ(R))." Cancer.gov. NCI/NIH, 8 Oct. 2014. Web. 21 Oct. 2014.

Pappo, Alberto S., ed. Pediatric Bone and Soft Tissue Sarcomas. New York: Springer, 2006. Print.

Parker, Philip M., and James N. Parker. Ewing’s Sarcoma: A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References. San Diego: ICON Health, 2004. Digital file.

US Natl. Lib. of Medicine Genetics Home Reference. "Ewing Sarcoma." Genetics Home Reference. US NLM/NIH, 20 Oct. 2014. Web. 21 Oct. 2014.

Theroux, Nicole, et al. Ewing’s Sarcoma Family of Tumors: A Handbook for Families. 1999. Glenview: Assoc. of Pediatric Oncology Nurses (US), 2006. Print.

In The Giver, what does it mean when Jonas says we have to protect people from wrong choices? And is it true that since everyone is the same in...

In chapter 13, Jonas and the Giver discuss colors and the inability of community members to see them. More importantly, the option to choose between different colors is automatically taken away from people because they can't see them. Jonas is frustrated because of this, but as the conversation develops, he says that it is probably better that people don't choose their own mates or careers. Jonas says that if people chose their own mates and...

In chapter 13, Jonas and the Giver discuss colors and the inability of community members to see them. More importantly, the option to choose between different colors is automatically taken away from people because they can't see them. Jonas is frustrated because of this, but as the conversation develops, he says that it is probably better that people don't choose their own mates or careers. Jonas says that if people chose their own mates and jobs, it would be "very frightening. I can't even imagine it. We really have to protect people from wrong choices. . . [It's] much safer" (98-99). Apparently, in Jonas's community, they value controlled safety over freedom of choice and allowing people to make mistakes.

People are equal in many ways in this community because any choices of preference have been taken away. This does create equality because they have limited options in life to choose from. If everyone only has the same number of choices to make each day, and none of them are choices of unique preference, then there is an equal playing field for life. However, once one person is able to make a different choice than others in the community, there is inequality. The consequence of just one person being able to choose something different from someone else can create envy and strife. Once that happens, equality is eliminated.

If it is true that nothing or less than nothing happens in Waiting for Godot, how is it that we manage to be entertained as the audience? If...

I believe that most people would agree that the play is intended to illustrate the author's vision that there is no meaning or purpose in life. It might be called existentialistic, but existentialism goes beyond asserting that there is no external or supernatural meaning to human existence. Existentialism seems to encourage people to create their own meaning in their lives. I don't believe Beckett cared whether his audiences did that or not. He seems utterly nihilistic. He does not seem to want to suggest any solution to the human dilemma. Life is meaningless. Period. There is a barely discernible humor running throughout the play. It can be regarded as a comedy. The fact that life is a bad joke on all of us can be seen as funny. The two tramps are funny. When the play was first produced in America, one of the tramps was played by the comedian Bert Lahr, who played the Cowardly Lion in the famous movie The Wizard of Oz. Lahr understood the play as a comedy. It is also easy to see the relationship between Lucky and Pozzo as comical. 

Some people can't stand the play because, as you say, "nothing or less than nothing happens." It is not like most plays, like those of Ibsen for instance, in which the author holds the audience with some big social problem to which he offers a solution. If life is meaningless, then there really is no problem, and there can be no solution and no reasonable motivation. People who like the play appreciate its comic, or ironic, picture of the meaninglessness of existence. This seems like a sophisticated attitude. Life has no meaning, but still we go on living. The alternative is to hang ourselves--but why do that? That wouldn't have any meaning either. So we all go on waiting for something to happen, like Vladimir and Estragon. They are just tramps and we laugh at them--but at least they know what they are waiting for. They are waiting for a man named Godot because they obviously expect him to give them a handout. There must really be a man named Godot and he must know they are waiting for him. Twice he sends a boy to tell them he can't come today but will come tomorrow. Part of what is laughable about the situation is that these two tramps should expect anyone to care about them. Godot may care a little, but not very much.

The play was first produced in French in 1953. That was about sixty-three years ago, and it is still being staged all over the world, still being talked about and debated over, still being assigned reading in college courses. It has become a classic--and yet, "nothing or less than nothing happens." If life is meaningless, then it is quite appropriate that a play should be meaningless. That is what makes it "absurd." Since it is absurd, it is funny, in an unsettling sort of way. It doesn't tell audiences to find their own meaning, or to create their own (perhaps arbitrary and contrived) meaning. It leaves them wondering what it's all about, just as they are wondering whether Godot will ever show up.

I feel I have just added more words to the millions that have already been expended trying to explain the "meaning" of this annoying but fascinating play.

What is Reye syndrome? |

Causes and Symptoms

The exact cause of Reye syndrome has not been determined, but the majority of patients develop the disease while recovering from a mild viral illness, such as chickenpox, influenza, or a minor respiratory illness. It is theorized that the virus combines with another unknown substance or substances in the body to produce a damaging poison. Reye syndrome usually occurs in children between four and twelve years of age. For reasons not well understood, the taking of salicylates, such as aspirin, during viral illnesses may precipitate the development of this potentially fatal illness.

The first symptom of the disease is a sudden onset of vomiting, then high fever, headache, and drowsiness. Blood sugar levels drop, while blood ammonia and acidity levels increase. As the disease progresses, alternating states of excitation and confused sleepiness may occur, as well as convulsions and a loss of consciousness. In the final stages of the disease, damage occurs to the liver, kidneys, and brain. The liver swells and develops large amounts of fat deposits. The brain
cells swell and pressure builds in the skull, followed by coma, permanent brain damage, and, in some cases, death.

Reye syndrome is often mistaken for a number of other disorders, including meningitis, encephalitis, diabetic shock, or poisoning, potentially complicating the early diagnosis that is crucial for treating this condition.

Treatment and Therapy

There is no known cure for Reye syndrome. Early recognition and specialized care may be lifesaving. If a child begins to exhibit symptoms of Reye syndrome shortly after a viral illness, then competent medical care must be sought immediately. Treatment consists of helping the victim survive the first few days of the illness through intake of fluids, glucose, and other nutrients. If the patient survives the first three or four days, the symptoms usually subside and recovery follows. The degree of recovery, however, depends upon the degree of brain swelling of the patient during the illness. Some children suffer permanent brain damage.

Medication, such as mannitol, or surgery will reduce the pressure within the skull if it reaches dangerous levels. Although it has not been proven that aspirin causes or promotes Reye’s syndrome, based on a variety of medical studies, it is recommended that aspirin not be given to children with
viral infections, especially chickenpox and influenza. With few exceptions, acetaminophen or ibuprofen are safe alternatives.

Perspective and Prospects

Reye syndrome was first described by an Australian pathologist, R. D. K. Reye, in 1963. In the early 1980s, approximately 50 percent of the cases were fatal, but improved diagnosis and treatment of the disease had reduced that number to less than 10 percent by 2006.

Bibliography

Badash, Michelle. "Reye's Syndrome." Health Library, November 26, 2012.

Bhutta, Adnan T. “Reye’s Syndrome: Down but Not Out.” Southern Medical Journal 96, no. 1 (January 1, 2003): 43–46.

Parker, James N. and Phillip M. Parker.Reye’s Syndrome: A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References. ICON Group, 2007.

Kliegman, Robert and Waldo E. Nelson, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia: Saunders/Elsevier, 2011.

Taubman, Bruce. Your Child’s Symptoms: A Parent’s Guide to Understanding Pediatric Medicine. New York: Simon & Schuster, 1992.

Woolf, Alan D., et al., eds. The Children’s Hospital Guide to Your Child’s Health and Development. Cambridge, Mass.: Perseus, 2002.

What is sinusitis? |

Causes and Symptoms

The sinuses are airspaces in the skull that exist in the forehead just above the eyes, on either side of the nose below the eyes, and in the area just above the nose and in between the eyes. The sinuses are lined with mucus and tiny hairs, called cilia, which trap inhaled particles and bacteria and move them back out through the nose. This action serves as a natural defense system to eliminate these potential irritants that are inhaled during normal breathing. The tracts through which the sinuses drain are relatively small and easily blocked by swelling of the area. This blockage can impair drainage and cause the buildup of normal sinus secretions.

The term “sinusitis” refers to irritation or swelling of the sinuses and their membranes. Typical symptoms may include a feeling of congestion or pressure in the nose or face and runny nose with secretions that may vary in color from clear to yellowish green to bloody. The facial pressure is often worse when bending forward.

Most often, sinusitis is precipitated by the common cold. Another frequent cause is allergies, with typical symptoms of sneezing, runny nose, and itchy, watery eyes. An allergic patient who is sensitive to a particular airborne substance (pollen, ragweed, dust, animal dander) has a particularly vigorous response when these particles land in the nose and enter the sinuses. An increased production of mucus and the body’s natural immune defenses combine to produce thick and copious nasal secretions that can fill the sinuses in an attempt to eliminate the offending agent.

Another factor that may predispose a patient to sinusitis is environmental exposure to smoke or air pollution, which are natural irritants to the sinuses. Problems that cause a blockage of the sinus drainage system by things such as nasal polyps, a deviated septum, or pregnancy (which leads to swelling of the nasal membranes as a result of hormonal changes) can interfere with mucus drainage from the sinuses. Finally, other genetic diseases such as cystic fibrosis or disorders of the immune system can predispose patients to sinusitis.

Although most cases of sinusitis are caused by viruses or allergies, these can often lead to infection by bacteria if they do not resolve promptly. Bacterial sinusitis requires treatment with antibiotics to avoid the rare but serious complications of infection of the orbit or infection of the brain and its surrounding tissues.

The distinction between bacterial and other causes of sinusitis is most accurately based on the patient’s symptoms and a physical examination. A patient is more likely to have bacterial sinusitis if two or three of the following symptoms are present for at least seven days: facial pressure, nasal congestion, discolored nasal mucus, decreased sense of smell, productive or “wet” cough, fever, tooth pain on the upper jaw, or bad breath.

Sinus X-rays, done frequently in the past, are not considered a reliable diagnostic test for sinusitis. Though sinus computed tomography (CT) scans allow intricate visualization of sinus anatomy, they do not reliably distinguish bacterial sinusitis from other forms and are useful only in cases of long-standing, refractory symptoms for which sinus surgery is being considered.

Treatment and Therapy

The initial treatment of sinusitis involves extra fluids, anti-inflammatory drugs such as ibuprofen, antihistamines, short-term use of nasal decongestant sprays (no longer than three days), and oral decongestants such as pseudoephedrine. Humidified air (for example, steam from a hot shower) and nasal irrigation with water or saline can offer short-term symptom relief.

If allergies are the cause of sinusitis, then oral or nasal allergy medications are appropriate. Examples are nonprescription antihistamines such as chlorpheniramine or diphenhydramine; they can cause drowsiness in some patients. Loratadine and other related, newer generation antihistamines are also available over the counter. They offer once-daily dosing and are significantly less sedating. Other nasal sprays such as topical steroids are available by prescription and offer significant relief.

If symptoms persist longer than seven to fourteen days, then antibiotic therapy may be necessary and evaluation by a health care provider is warranted. Many different types of antibiotics are effective for sinusitis, and prescription practices vary. Initial treatment is typically for two weeks.

Perspective and Prospects

Prior to the antibiotic era, the treatment of sinusitis involved drainage of the sinuses by extracting a tooth, puncturing the roof of the mouth, or entering the nose and creating a drainage tract through which secretions could be removed and the sinuses could be irrigated with fluid for cleansing. Given the invasiveness of these procedures, they have become uncommon with the development of effective antibiotic therapy.

The development of tiny, high-resolution cameras known as endoscopes in the 1950s created a revolution in the understanding of sinus disease. Direct visualization of the nasal passages and sinus drainage tracts allowed a better understanding of the sinus anatomy and thus led to the use of this equipment to facilitate surgical treatment.

Occasionally, patients with recurrent symptoms require surgical removal of infected sinus tissue and enlargement of the natural drainage tracts to minimize sinus obstruction. A specialist in otorhinolaryngology (or otolaryngology) can perform such surgery using an endoscope, without the need for general anesthesia. Patients do not typically require hospitalization, and complications are rare.

Bibliography

Beers, Mark H., et al., eds. The Merck Manual of Diagnosis and Therapy. 18th ed. Whitehouse Station, N.J.: Merck Research Laboratories, 2006.

Brook, Itzhak, ed. Sinusitis: From Microbiology to Management. New York: Taylor & Francis, 2006.

Carson-DeWitt, Rosalyn, and Brian Randall. "Sinusitis." Health Library, Sept. 30, 2012.

"The Difference between Sinusitis and a Cold." HealthyChildren.org. American Academy of Pediatrics, May 11, 2013.

Kennedy, David W., and Marilyn Olsen. Living with Chronic Sinusitis: A Patient’s Guide to Sinusitis, Nasal Allegies, Polyps, and Their Treatment Options. Long Island, N.Y.: Hatherleigh Press, 2007.

McCaffrey, Thomas. “Functional Endoscopic Sinus Surgery: An Overview.” Mayo Clinic Proceedings 68 (June, 1993): 571–577.

Mickelson, Samuel, and Michael Benninger. “The Nose and Paranasal Sinuses.” In Textbook of Primary Care Medicine, edited by John Noble. 3d ed. St. Louis, Mo.: Mosby, 2001.

"Sinusitis." MedlinePlus, Apr. 22, 2013.

"Sinusitis." National Institute of Allergy and Infectious Diseases, Jan. 2012.

Younis, Ramzi T., ed. Pediatric Sinusitis and Sinus Surgery. New York: Taylor & Francis, 2006.

What is pericardial effusion? |

Risk factors: For cancer patients, the advanced stages of cancer pose
the greatest risk. A less serious but still common risk is earlier radiation
treatments to the chest, especially for lung cancer.

Etiology and the disease process: The causes of effusions in patients
who do not have cancer are many, including infection, autoimmune disorders such as
lupus, certain medications, uremia, and trauma near the heart. The
cause of malignant pericardial effusion in cancer patients is cancer that develops
in the pericardium or the heart muscle, or cancer that has metastasized from
almost anywhere else in the body, particularly the lungs, breasts, esophagus,
colon, prostate, and even bone marrow (leukemia) and skin (melanoma). Radiation
therapy for cancer that occurred near the heart can also cause pericardial
effusion, as well as certain chemotherapeutic drugs, such as doxorubicin and
cyclophosphamide.

Cancerous cells rub against the pericardium. This irritant causes fluid to build up, much the way a blister forms under the skin. Some cancers produce little fluid but cause the pericardium to thicken and become rigid. Both conditions are serious.

An effusion can be chronic (present over time) or acute (occurring suddenly). If the fluid collects slowly over time, the pericardium may stretch enough to hold it. The patient usually feels no symptoms until a large amount of fluid accumulates. When the volume of fluid reaches a critical amount or when fluid accumulates rapidly even a relatively small amount of fluid a condition known as cardiac tamponade occurs. At this stage, the effusion surrounds and squeezes at the heart. This interferes with the heart’s ability to effectively pump blood. Cardiac tamponade is a medical emergency that can be fatal if not promptly treated.

Incidence: Because effusions develop from a number of different diseases or conditions, any patient with any of the many conditions that can produce an effusion may be stricken with one. Effusions affect both sexes, all age groups, and all racial and ethnic groups.

According to the US National Cancer Institute, approximately one-third of
patients with lung cancer have a pericardial effusion caused by the spread of
their cancer at the time of their death. Lung cancer
is the most common cause of malignant pericardial effusions, accounting for
one-third of cases, followed by breast cancer (25 percent) and
hematological malignancies such as leukemia, Hodgkin disease, and
non-Hodgkin
lymphoma (15 percent).

Symptoms: Symptoms of an effusion are similar to symptoms associated with heart problems and include chest pain, rapid heartbeat, shortness of breath, dizziness or fainting, difficulty in swallowing, cough, and low blood pressure.

Screening and diagnosis: Spotting an effusion is relatively easy for
doctors. X-rays and other imaging techniques reveal the characteristic
“water-bottle” shape of the swollen pericardial sac. Doctors may perform
pericardiocentesis, a procedure that uses a needle to
withdraw some of the excess fluid. Doctors may then analyze the fluid to determine
the cause of the effusion.

Treatment and therapy: For cancer patients, treatment generally
involves relief of symptoms, because pericardial effusions usually arise in the
later stages of cancer, often in the last few week of life. Doctors use various
noninvasive and surgical procedures to drain the fluid, thus offering the patient
some relief. In addition, doctors may prescribe anti-inflammatory drugs.

Prognosis, prevention, and outcomes: There is no way to prevent an
effusion in cancer patients. The prognosis for cancer patients with malignant
pericardial effusion is poor. One study showed that of patients diagnosed with
malignant pericardial effusions, 86 percent died within a year of diagnosis. About
one-third died within the first month.

Gornik, H., M.
Gerhard-Herman, and J. Beckman. “Abnormal Cytology Predicts Poor Prognosis
in Cancer Patients with Pericardial Effusion.” Journal of Clinical
Oncology 23.22 (2005): 5211–216. Print.

Herzog, Eyal, ed. Management of
Pericardial Disease. Cham: Springer, 2014. Print.

Kiselevsky, Mikhail V., ed.
Malignant Effusions: Pleuritis, Ascites, Pericardites.
Dordrecht: Springer, 2012. Print.

Laham, R., et al.
“Pericardial Effusion in Patients with Cancer: Outcome with Contemporary
Management Strategies.” Heart 75.1 (1996): 67–71.
Print.

"Malignant Pericardial Effusion."
National Cancer Institute. US Dept. of Health and Human
Services, 16 Sept. 2014. Web. 5 Dec. 2014.

Moore, K., and L.
Schmais. Living Well with Cancer: A Nurse Tells You Everything You
Need to Know About Managing the Side Effects of Your Treatment.
New York: Putnam, 2001. Print.

What is myocarditis? |

Definition

Myocarditis is an
inflammation of the heart’s muscular wall, the myocardium. Although rare, it can be devastating. Myocarditis can occur with no symptoms and can remain undiagnosed.

Causes

Many cases of myocarditis have no identifiable cause and are called idiopathic myocarditis. When a cause is identified, the myocarditis falls into one of three categories: infectious, toxic, and immune-mediated.

Infectious myocarditis is caused by either a viral
infection from viruses such as measles,
rabies, or human immunodeficiency virus (HIV); a
bacterial
infection from bacteria such as diphtheria or
Mycobacterium; or a fungal infection from
Aspergillus or
Candida.

Toxic myocarditis is caused by drugs such as chemotherapeutic drugs, lithium,
or cocaine; by heavy metals such as copper, iron, or lead; by toxic substances
such as arsenic, carbon monoxide, or other inhalants; and by physical agents such
as electric shock or radiation.

Immune-mediated myocarditis is caused by an allergic reaction to penicillin or streptomycin; by alloantigens, including heart
transplant rejection; and by autoantigens, including Chagas’
disease, scleroderma, or lupus.

Risk Factors

There are no known risk factors for developing myocarditis.

Symptoms

The symptoms of myocarditis vary from person to person depending on the cause and the severity. Furthermore, some people have no symptoms and are thus asymptomatic. The following symptoms may appear slowly or suddenly: flulike complaints, including fever, fatigue, muscle pain, vomiting, diarrhea, and weakness; a rapid heart rate; chest pain; shortness of breath and respiratory distress; and a loss of consciousness. Sudden, intense myocarditis can lead to congestive heart failure and death.

Screening and Diagnosis

The diagnosis of myocarditis is often difficult. There is no specific test for
it. Many other causes of heart problems must be ruled out. To do this, a doctor
will ask the patient about symptoms and medical history and will perform a
physical exam. Tests may include an electrocardiogram (ECG), which records the
heart’s activity by measuring electrical currents through the heart muscle; a
chest X ray, which uses radiation to take pictures of structures inside the body;
a cardiac enzyme blood test (because, in some cases, certain enzymes are
elevated); an echocardiogram, which uses high-frequency sound waves, or
ultrasound, to examine the size, shape, and motion of the heart; a
biopsy (the removal of a sample of heart tissue to test for
infection); and cardiovascular magnetic resonance imaging (the use of
magnetic waves to take pictures of structures inside the body).

Treatment and Therapy

The universally recommended therapy for myocarditis is bed rest, no physical
activity, and supplemental oxygen. Corticosteroids may be given to help
inflammation, and the patient will most likely be admitted to a hospital.

Specific treatment is directed at the underlying cause, if possible. For
instance, if the cause is a bacterial infection, the doctor will prescribe
antibiotics; if the cause is viral, the doctor will
prescribe antiviral agents. Immunosuppressive therapy may be used if the
myocarditis is caused by an autoimmune disorder such as lupus or scleroderma.

If heart failure symptoms are present, the doctor will prescribe medications to
support the function of the heart. These medications include diuretics,
ACE-inhibitors, beta-blockers, and antiarrhythmic agents. Additionally, a
defibrillator, which helps maintain the normal rhythm of the heart, may be
implanted into the patient’s chest. Severe cases may require a cardiac transplant.

Prevention and Outcomes

Myocarditis is difficult to prevent. To help reduce the chance of getting myocarditis, one should reduce exposure to identified causes. Some examples of prevention include practicing good hygiene to avoid the spread of infection (for example, washing one’s hands regularly), always using latex condoms during sexual intercourse, having monogamous sex, and avoiding illegal drugs.

Bibliography

Brady, W. J., et al. “Myocarditis: Emergency Department Recognition and Management. Emergency Medicine Clinics of North America 22, no. 4 (2004): 865-885.

Crawford, Michael, ed. Current Diagnosis and Treatment—Cardiology. 3d ed. New York: McGraw-Hill Medical, 2009.

Feldman, A. M., and D. McNamara. “Myocarditis.” New England Journal of Medicine 343, no. 19 (2000): 1388-1398.

Felker, G. M., et al. “Underlying Causes and Long-Term Survival in Patients with Initially Unexplained Cardiomyopathy.” New England Journal of Medicine 342 (2000): 1077.

Zipes, Douglas P., et al., eds. Braunwald’s Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia: Saunders/Elsevier, 2008.

What is polycythemia vera? |

Related conditions:
Essential thrombocythemia, idiopathic myelofibrosis

Definition:
Polycythemia vera is a rare myeloproliferative disorder that causes chronic overproduction of red blood cells and possibly of white cells and platelets. Although these cells function normally, their overabundance causes increased blood viscosity and decreased blood flow, with possible clot formation and resultant heart attack or stroke, and possible systemic decreases in oxygen supply, resulting in compromised muscle function, lung function, and visual acuity, or in angina, congestive heart failure, or gout.

Risk factors: Polycythemia vera occurs more frequently in men aged sixty and older and in Jews of eastern European descent. Although family history is not a risk factor, polycythemia vera occasionally occurs in more than one family member.

Etiology and the disease process: The cause of polycythemia vera is unknown. Disease progression is slow, as is symptom onset. Polycythemia vera occurs because of a deoxyribonucleic acid (DNA) mutation in most cases, in the JAK2 gene in hematopoietic stem cells (blood-forming cells in bone marrow) that triggers blood cell overproduction.

In rare instances, myelofibrosis abnormal, fibrous bone marrow tissue may develop and may lead to acute myelogenous leukemia (AML), an aggressive disease characterized by overabundance in blood and bone marrow of immature white blood cells.

Incidence: The reported incidence ranges from 0.5 to 2.5 per 100,000 people worldwide.

Symptoms: Overabundance of red blood cells and platelets causes the symptoms associated with polycythemia vera. Symptoms may include dizziness, enlarged spleen, fatigue, headache, itchy or flushed skin, kidney stones, profuse sweating, shortness of breath, stomach ulcers, tinnitus, and vision problems.

Screening and diagnosis: Due to its slow progression and delayed expression of nonspecific symptoms, polycythemia vera may be diagnosed via routine blood testing if results indicate a 33 percent or greater increase in hematocrit level, hemoglobin concentration, and red cell count. Other indicators may be elevated platelet count or white cell count, presence of the JAK2 mutation in blood cells, or low erythropoietin (EPO) level (determined by assay).

Treatment and therapy: Initial options are phlebotomy to reduce blood volume and drug therapy to decrease cell count. The platelet count-lowering drug anagrelide or the myelosuppressive drugs hydroxyurea, interferon alpha, and radioactive phosphorus (32P) may be used. However, side effects are associated with all treatments, including phlebotomy, which can result in anemia.

Prognosis, prevention, and outcomes: There is no cure for polycythemia vera. If untreated, it can lead to death. If treated, life expectancy and quality of life may be unaffected. Response to therapy may be monitored via hematocrit levels and hemoglobin concentrations.

"Chronic Myeloproliferative Neoplasms Treatment: Polycythemia Vera." National Cancer Institute. Natl. Inst. of Health, 11 Nov. 2014. Web. 11 Dec. 2014.

Goldman, Lee, and Andrew I. Schafer. Goldman's Cecil Medicine. 24th ed. Philadelphia: Elsevier, 2012. Print.

Hoffman, Ronald, et al. Hematology: Basic Principles and Practice. 6th ed. Philadelphia: Elsevier, 2012. Print.

"Polycythemia Vera." Merck Manual. Merck, Apr. 2014. Web. 11 Dec. 2014.

"What Is Polycythemia Vera?" National Heart, Lung, and Blood Institute. Natl. Inst. of Health, 1 Mar. 2011. Web. 11 Dec. 2014.

What are headaches? |

Causes and Symptoms

The International Headache Society has developed the current classification system
for headaches. This system includes fourteen exhaustive categories of headache
with the purpose of developing comparability in the treatment and study of
headaches. Headaches most commonly seen by health care providers can be classified
into four main types: migraine, tension-type, cluster, and other primary
headaches.

Migraine
headaches have an estimated lifetime prevalence of 18
percent, according to the International Association for the Study of Pain.
Migraine headaches are more common in women, and they tend to run in families;
they are usually first noticed in adolescence or young adulthood. For the
diagnosis of migraine without aura (formerly called common migraine or hemicrania
simplex), the person must experience at least five headache attacks, each lasting
between four and seventy-two hours with at least two of the following
characteristics: The headache is unilateral (occurs on one side), has a pulsating
quality, is moderate to severe in intensity, or is aggravated by routine physical
activity. Additionally, one of the following symptoms must accompany the headache:
nausea and/or vomiting or sensitivity to light or sounds. The person’s medical
history, a physical examination, and (where appropriate) diagnostic tests must
exclude other organic causes of the headache, such as brain tumor
or infection such as meningitis. Migraine with aura is far
less common. Migraine with aura (formerly called classical migraine) refers to a
migraine headache with visual disturbances such as the appearance of flickering
lights, spots, or lines and/or the loss of vision; sensory disturbances such as
numbness and/or tingling; and impairment of speech—symptoms that gradually develop
over five to twenty minutes and that last for less than an hour. There are several
subtypes of migraines with aura, including typical aura with migraine headache,
typical aura with nonmigraine headache, typical aura without headache, familial
hemiplegic migraine (migraine with aura including motor weakness in a patient with
a first- or second-degree relative with hemiplegic migraine), sporadic hemiplegic
migraine (migraine with aura including motor weakness in a patient with no first-
or second-degree relatives with hemiplegic migraine), and basilar-type migraine
(migraine with brain-stem aura).

Migraines may be triggered or aggravated by physical activity; by menstruation;
by relaxation after emotional stress; by the ingestion of tyramine in cheddar
cheese or wine, of chocolate, of monosodium glutamate, of sodium nitrate in
processed meats, of nitrites in red wine, and of aspartame; by prescription
medications (including birth control pills and hypertension medications); and by
changes in the weather. Yet the precise pathophysiology of migraines is unknown.
Reduced blood volume in the brain is characteristic of migraine with aura, while
the pathogenesis of migraine without aura is uncertain.

Tension-type headache is the most common type of headache; its mean lifetime
prevalence is approximately 46 percent globally. Tension-type headaches are not
hereditary, occur slightly more frequently in women than in men, and have a mean
age of onset of twenty-five to thirty years, although they can appear at any time
of life. For the diagnosis of tension-type headaches, the person must experience
at least ten headache attacks lasting from thirty minutes to seven days each, with
at least two of the following characteristics: The headache has a pressing or
tightening (nonpulsating) quality, is mild or moderate in intensity (may inhibit
but does not prohibit activities), is bilateral in location, and is not aggravated
by routine physical activity. Additionally, nausea, vomiting, and light or sound
sensitivity are absent or mild. Tension-type headaches have been divided into
episodic and chronic subtypes, and the episodic subtype has been further divided
into frequent and infrequent subtypes. Tension-type headache sufferers describe
these headaches as a band-like or cap-like tightness around the head, and/or
muscle tension in the back of the head, neck, or shoulders. The pain is described
as slow in onset with a dull or steady aching.

Tension-type headaches are believed to be precipitated primarily by psychogenic
factors but can also be stimulated by muscular and spinal disorders, jaw
dysfunction, paranasal sinus disease, and traumatic head
injuries. The pathophysiology of tension-type headaches is
controversial. Tension-type headaches have been attributed to the fascia of the
head, neck, and shoulder muscles causing myogenic-referred pain and to peripheral
pain mechanisms, particularly in episodic tension-type headaches.

Cluster
headaches are the least frequent of the headache types and
are thought to be the most severe and painful. Cluster headaches are more common
in men, with an estimated prevalence of less than 1 percent in the general
population. Typically, these headaches first appear between ten and thirty years
of age, although they can start later in life. Likely risk factors include a
family history of cluster headaches, and possible risk factors include a history
of tobacco smoking or head trauma. For the diagnosis of cluster headaches, the
person must experience at least five severely painful headache attacks with
strictly unilateral pain lasting from fifteen minutes to three hours. One of the
following symptoms must accompany the headache on the painful side of the face: a
bloodshot eye, lacrimation, nasal congestion, nasal discharge, forehead and facial
sweating, contraction of the pupil, or a drooping eyelid. Physical and
neurological examination and imaging must exclude organic causes for the
headaches, such as tumor or infection. Cluster headaches often occur once or twice
daily, or every other day, but can be as frequent as eight attacks in one day,
recurring on the same side of the head during the cluster period. The temporal
“clusters” of these headaches give them their descriptive name.

A cluster headache is described as a severe, excruciating, piercing, sharp, and
burning pain through the eye. The pain is occasionally throbbing but always
unilateral. Radiation of the pain to the teeth has been reported. Cluster headache
sufferers are often unable to sit or lie still and are in such pain that they have
been known, in desperation, to hit their heads with their fists or to smash their
heads against walls or floors.

Cluster headaches can be triggered in susceptible patients by alcohol, histamine,
or nitroglycerine. Because these agents all cause the dilation of blood vessels,
these attacks are believed to be associated with dilation of the temporal and
ophthalmic arteries and other extracranial vessels. There is no evidence that
intracranial blood flow is involved. Cluster headaches have been shown to occur
more frequently during the weeks before and after the longest and shortest days of
the year, lending support for the hypothesis of a link to seasonal changes.
Additionally, cluster headaches often occur at about the same time of day in a
given sufferer, suggesting a relationship to the circadian
rhythms of the body. Vascular changes, hormonal changes,
neurochemical excesses or deficits, histamine levels, and autonomic nervous system
changes are all being studied for their possible role in the pathophysiology of
cluster headaches.

Other primary headaches, using the International Headache Society’s classification
scheme, constitute many of the headaches not mentioned above, including stabbing
headache (occurs spontaneously in the absence of organic disease), cough headache
(brought on by and occurring only in association with coughing or straining),
exertional headache (brought on by and occurring only during or after physical
exertion), headache associated with sexual activity (brought on by and occurring
only as sexual excitement increases), hypnic headache (dull headaches that awaken
the patient from sleep), and thunderclap headache (extremely painful headache with
an abrupt onset).

Distinct from the primary headache types, which are often considered to be chronic
in nature, secondary headaches signify an underlying disease or other medical
condition. Secondary headaches can display pain distribution and quality similar
to those seen in primary headaches. Secondary headaches of concern are usually the
first or worst headache the patient has had or are headaches with recent onset
that are persistent or recurrent. Secondary headaches typically occur for the
first time in close temporal relation to another disorder that causes headaches.
Other signs that cause a high index of suspicion include an unremitting headache
that steadily increases without relief, accompanying weakness or numbness in the
hands or feet, an atypical change in the quality or intensity of the headache,
headache upon recent head trauma or a family history of cardiovascular problems or
cancer. Such headaches can point to hemorrhage, infection such as meningitis,
stroke, tumor, brain abscess, drug withdrawal, and hematoma, which are serious and
potentially life-threatening conditions. A thorough evaluation is necessary for
all patients exhibiting the danger signs of secondary headache.

Treatment and Therapy

Because there are several hundred causes of headaches, the evaluation of headache
complaints is crucial. Medical science offers myriad evaluation techniques for
headaches. The initial evaluation includes a complete history and physical
examination to determine the factors involved in the headache complaint, such as
the general physical condition of the patient, neurological functioning,
cardiovascular condition, metabolic status, and psychiatric condition. Based on
this initial evaluation, the health care professional may elect to perform a
number of diagnostic tests to confirm or reject a diagnosis. These tests might
include blood studies, x-rays, computed tomography (CT) scans,
psychological evaluation, electroencephalograms (EEGs),
magnetic
resonance imaging (MRI), or studies of spinal fluid.

Once a headache diagnosis is made, a treatment plan is developed. In the case of
secondary headaches, treatment may take varying forms depending on the underlying
cause, from surgery to the use of prescription medications. For migraine,
tension-type, and cluster headaches, there are several common treatment options.
Headache treatment can be categorized into two types: abortive (symptomatic)
treatment or prophylactic (preventive) treatment. Treatment is tailored to the
type of headache and the type of patient.

A headache is often a highly distressing occurrence for patients, sometimes
causing a high level of anxiety, relief-seeking behavior, lost productivity, and
reduced quality of life. The health care provider must consider not only
biological elements of the illness but also possible resultant psychological and
sociological elements as well. An open, communicative relationship with the
patient is paramount, and treatment routinely begins with soliciting patient
collaboration and providing patient education. Patient education takes the form of
normalizing the headache experience for patients, thereby reducing their fears
concerning the etiology of the headache or about being unable to cope with the
pain. Supportiveness, understanding, and collaboration are all necessary
components of any headache treatment.

There are a number of abortive pharmacological treatments for migraine headaches.
Ergotamine tartrate (an alkaloid or salt) is effective in terminating migraine
symptoms by either reducing the dilation of extracranial arteries or in some way
stimulating certain parts of the brain. Isometheptene, another effective treatment
for migraine, is a combination of chemicals that stimulates the sympathetic
nervous system, provides analgesia, and is mildly tranquilizing. Another class of
medications for migraines are nonsteroidal anti-inflammatory drugs (NSAIDs); these
drugs, as the name implies, reduce inflammation. Both narcotic and nonnarcotic
pain medications are often used for migraines, primarily for their analgesic
properties, particularly acetaminophen. Antiemetic medications prevent or arrest
vomiting and have been used in the treatment of migraines. Sumatriptan, a
vasoactive agent that increases the amount of the neurochemical serotonin in the
brain, shows promise in treating migraines that do not respond to other
treatments.

There are several nonpharmacological treatment options for migraine headaches.
These include stress management, relaxation training, biofeedback
(a variant of relaxation training), psychotherapy (both individual and family),
and the modification of headache-precipitating factors (such as avoiding certain
dietary precipitants). Each of these treatments has been found to be effective for
certain patients, particularly those with chronic migraine complaints. For some
patients, they can be as effective as pharmacological treatments. The exact
mechanism of action for their effect on migraines has not been established. Other
self-management techniques include lying quietly in a dark room, applying pressure
to the side of the head or face on which the pain is experienced, and applying
cold compresses to the head.

The abortive treatment options for tension-type headaches include narcotic and
nonnarcotic analgesics because of their pain-reducing properties. More often with
tension-type headaches, the milder over-the-counter pain medications (such as
aspirin or acetaminophen) are used. NSAIDs are a first-line treatment for
tension-type headaches.

Prophylactic treatments for tension-type headaches include tricyclic
antidepressants. Acupuncture and physical therapy may also be options to
treat frequent tension-type headaches. Physical therapy options include massage,
exercise, treatments to improve posture, and hot and cold packs. Electromyography
(EMG) biofeedback has also shown to have benefits in the treatment of tension-type
headaches. The identification and avoidance of possible tension-type headache
triggers, such as stress, irregular or inappropriate meals, high intake or
withdrawal of caffeine, dehydration, inadequate sleep, or
inappropriate sleep, may also be beneficial.

For cluster headaches, one of the most excruciating types of headache, the most
common abortive treatment is administering pure oxygen to the patient for ten
minutes. The exact mechanism of action is unknown, but it might be related to the
constriction of dilated cerebral arteries. Other first-line treatments include a
subcutaneous injection of sumatriptan and an intranasal spray containing
zolmitriptan. Ergotamine tartrate or similar alkaloids can also abort the attack
in some patients. Nasal drops of a local anesthetic (lidocaine hydrochloride) have
been used to ease cluster headaches. The efficacy of these treatments is
inconclusive.

Prophylactic treatment of this headache type is crucial. Verapamil is often given
in addition to abortive treatments and then withdrawn at the end of a cluster
episode. Lithium may be considered as a second-line medication if verapamil is
ineffective. Melatonin, corticosteroids, and dihydroergotamine may also be used
for the prophylactic treatment of cluster headaches.

While no nonpharmacological treatment strategies are routinely offered to cluster
headache patients, surgery is an option in severe cases in which the headaches are
resistant to all other available treatments. Subcutaneous occipital nerve
stimulation via an implant has been reported to improve chronic cluster headaches.
Sphenopalatine ganglion stimulation via an implant may reduce the frequency and
intensity of cluster headache attacks. Modest successes have been found with these
extreme treatment options.

Perspective and Prospects

Headaches are among the most common complaints to physicians and quite likely have
been a problem since the beginning of humankind. Accounts of headaches can be
found in the clinical notes of Arateus of Cappadocia, a first-century physician.
Descriptions of specific headache subtypes can be traced to the second century in
the writings of the Greek physician Galen. Headaches are prevalent health
problems that affect all ages and sexes and those from various cultural, social,
and educational backgrounds.

The prevalence of headaches is greater in women, although the reason is unknown.
Age seems to be a mediating factor as well, with significantly fewer people over
the age of sixty-five years reporting headache problems. There are no
socioeconomic differences in prevalence rates, with persons in high-income and
low-income brackets having similar rates.

The total economic costs of headaches are staggering. The expenses associated with
advances in assessment techniques and routine health care have risen rapidly. The
cost in lost productivity adds to this economic picture. The scientific study of
headaches is necessary to understand this prevalent illness. Efforts, such as
those by the International Headache Society, to develop accepted definitions of
headaches will greatly assist efforts to identify and treat headaches.

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