What is angiogenesis?

Relation of angiogenesis to cancer. In one way, a cancerous tumor is like any other bodily structure: its survival depends on the provision of oxygen and nutrients and the removal of waste. Cancerous tumors differ from normal tissue in that they tend to spread, or metastasize, without regard for normal borders between different tissues such as muscle, cartilage, and bone. Blood supply to a tumor enables it to spread. For its support and ability to grow, the cancer must in effect persuade the body to build vessels to and throughout the tumor, something that seems counterintuitive. In fact, the body contains defenses against this. As cancer develops, however, these defenses are short-circuited.

The way the tumor fools its host into cooperation is chemically, with proteins and enzymes found naturally in the body but used by the tumor to its advantage. Proteins that induce growth are known as growth factors. Researchers have shown evidence that one chemical secreted by tumors, vascular endothelial growth factor (VEGF), in effect attracts blood vessels. Induced by growth factors and possibly hormones, new blood vessels actually sprout from existing vascular tracts into and around the cancer. Researchers also report that breast cancer cells produce interleukin-8 (IL-8), a protein that normally attracts white blood cells to injuries and inflammation but is also known to be angiogenic.

Other researchers, exploring the role of certain enzymes in regulating angiogenesis in breast cancer, are focusing on the extracellular matrix, noncellular material that surrounds any tissue (picture the stuffing around mattress springs) and is common to both normal tissues and tumor cells. In addition to taking up space between cells (including cartilage, tendon, ligament, and bone), the extracellular matrix performs a critical function. Under normal circumstances after adulthood, the extracellular matrix prevents unauthorized (non-injury-related) angiogenesis and cell movement. Cancer short-circuits that inhibitory function. Compared with normal breast cells, some breast cancer cells have higher levels of certain enzymes that degrade heparan sulfate, an important component of the extracellular matrix. A weakened and degraded extracellular matrix might well enable abnormal cell movement and angiogenesis.

Preventing cancer-related angiogenesis: If tumors require angiogenesis to survive and spread, then it seems logical to discourage angiogenesis. Inhibitors of angiogenesis were first discovered in 1975 and since then have been detected in such diverse natural sources as tree bark, green tea, fungi, shark cartilage and muscle, sea coral, and various herbs. Potential methods to prevent or change the process of angiogenesis include blocking the chemical signals from the tumor, making these signals less effective; preventing the breaching of the extracellular matrix; and, after a tumor has already been supplied with blood vessels, causing the vessels to normalize, or stop supplying the tumor.

A number of angiogenesis inhibitors have been approved for use by the US Food and Drug Administration (FDA), most of which work by blocking VEGF. While promising, these drugs are still largely experimental, in part because of the complexity and diversity of the tumors themselves. What works for one tumor may not work for another. Another complication of agents that inhibit angiogenesis is the chaos they could produce in inflammation control and healing. Nevertheless, the possibility of inhibiting angiogenesis only where it is needed, with very targeted inhibitors and perhaps with the assistance of other drugs such as paclitaxel (Taxol) and cyclophosphamide (Cytoxan, Neosar) and such cyclooxygenase-2 (COX-2) inhibitors as celecoxib (Celebrex) and thalidomide, all of which interfere with angiogenesis, remains an attractive investigative path. Research and clinical trials are ongoing.

Bibliography

"Angiogenesis and Angiogenesis Inhibitors to Treat Cancer." Cancer.Net. Amer. Soc. of Clinical Oncology, July 2014. Web. 22 Aug. 2014.

Angiogenesis Foundation. Angiogenesis Foundation, 2014. Web. 22 Aug. 2014.

Chan, David. Breast Cancer: Real Questions, Real Answers. New York: Marlowe, 2006. Print.

Fakhrejahani, Elham, and Masakazu Toi. "Tumor Angiogenesis: Pericytes and Maturation Are Not to Be Ignored." Journal of Oncology 2012 (2012): 1–10. Web. 22 Aug. 2014.

Friedewald, Vincent, Aman U. Buzdar, and Michael Bokulich. Ask the Doctor: Breast Cancer. Kansas City: Andrews, 1997. Print.

Herman, Alexander B., Van M. Savage, and Geoffrey B. West. "A Quantitative Theory of Solid Tumor Growth, Metabolic Rate and Vascularization." PLoS ONE 6.9 (2011): 1–9. Web. 22 Aug. 2014.

Heymach, John V., George W. Sledge Jr., and Rakesh K. Jain. "Tumor Angiogenesis." Holland-Frei Cancer Medicine. Ed. Waun Ki Hong et al. 8th ed. Shelton: People's Medical, 2010. Print.

Link, John, et al. The Breast Cancer Survival Manual: A Step-by-Step Guide for Women with Newly Diagnosed Breast Cancer. 5th ed. New York: Holt, 2012. Print.

Sennino, Barbara, and Donald M. McDonald. "Controlling Escape from Angiogenesis Inhibitors." Nature Reviews: Cancer 12.10 (2012): 699–709. Print.

What is the significance of the last line in the novel Of Mice and Men?

The line at the end of the novel can be interpreted to mean that Slim and George are close friends now.

George and Lennie have always been friends, but they could never be equals.  George was Lennie’s protector.  When George met Slim, he was impressed with the fact that George and Lennie went around together.  Most men on the ranch were loners, always going from one place to another by themselves and never staying one place for long.

Slim seemed almost jealous for what George and Lennie had.  He was an impressive guy who had a good reputation on the ranch.  He interrogated George and Lennie from the beginning, curious about how they could travel in a pair and look out for each other.

"You guys travel around together?" His tone was friendly. It invited confidence without demanding it.

"Sure," said George. "We kinda look after each other." (Ch. 2)

What George and Lennie have is unique because Lennie is completely dependent on George.  George looks out for him, protects him, and defends him.  He also gets him out of trouble.  When Lennnie gets into trouble for killing Curley’s wife, George has more trouble than he can handle.  He has come to trust Slim, and Slim is the one who tries to comfort him.

Slim came directly to George and sat down beside him, sat very close to him. "Never you mind," said Slim. "A guy got to sometimes." (Ch. 6)

Slim understands the relationship between Lennie and George better than anyone else.  The other men assume that Lennie was dangerous and just tried to kill George, but Slim knows better.  He knows Lennie would never attack George, but that George had to do what he had to do to protect Lennie.  He tells George they will get a drink to show him that he is on his side.

The last line of the book indicates that Slim and George understand each other, but the other men on the ranch do not.  This puts Slim and George in a special kind of relationship, the friendship that both of them need.  They have the potential to go around together now like George and Lennie did, or George can stay put for a bit.

What are the characteristics of romantic novels?

Your question may refer to two styles of writing- romantic fiction or novels produced during the Romantic Period. I will describe both.

Romantic or romance novels focus on the story of a love relationship, typically between two people. This relationship is what ties the story together-- it creates continuity in the plot. In addition to a central romantic relationship, romantic novels ought to have an "emotionally satisfying or optimistic" resolution. Even if the characters face many hardships in their relationship, even if one dies, a romantic novel will tell a story where love wins at the end of the day.

Romantic literature, or that produced during the Romantic Period, describes a style of writing which flourished in the first half of the 19th century. Romantic Period novels are characterized by rich use of emotion and sensuality. Many novels written during this Period emphasize individual feeling and deal more with the emotional consequences of the story as opposed to a more "cut and dry" relation of events. 

How did the "Scopes Monkey Trial" represent a clash between urban and rural societies during the 1920's?

The case of State of Tennessee v. John Thomas Scopes, more commonly known as “the Scopes Monkey Trial,” represented a conflict between urban and rural environments because of the vast disparity in educational opportunities between the two types of settings and because of the far more prevalent role of religion in the daily lives and thought-processes of those inhabiting more rural communities. Tennessee, of course, is part of what became known (ironically, as a direct result of the “Scopes Monkey Trial,” when journalist and critic H.L. Menken, who covered the trial for his hometown newspaper, Baltimore Sun, referred derisively to the region in which the trial was taking place) as “the Bible Belt,” the large region that just so happens to overlap with the American South. When the State of Tennessee passed a law, known as the Butler Act, it made it a state crime to teach evolution in public schools. The operative section of that statute stated the following:

Section 1. Be it enacted by the General Assembly of the State of Tennessee, That it shall be unlawful for any teacher in any of the Universities, Normals and all other public schools of the State which are supported in whole or in part by the public school funds of the State, to teach any theory that denies the story of the Divine Creation of man as taught in the Bible, and to teach instead that man has descended from a lower order of animals.

That the State of Tennessee should pass a law such as the Butler Act was testament to the depths of its commitment to historical interpretation through the prism of Biblical scripture. (Interestingly, even today, Tennessee retains its strong beliefs in the Bible as the word of God and the source of knowledge on man’s origins; the American Bible Society ranks Chattanooga, Tennessee, as the most “Bible-minded city” in the United States). This is not to suggest that citizens of the Bible Belt are any less intelligent than anybody else; it is to suggest that the more insular nature of many rural communities across the American South (and in Texas and Oklahoma) and the region’s history of antipathy towards its more “cosmopolitan” neighbors to the north has bred resentment towards outside influences, including in the area of scientific developments that may challenge preexisting beliefs on a whole range of subjects. And, socioeconomic distinctions between such southern rural areas and more densely-populated urban areas, including in the South, were, and too-often remain, represented in the qualities of education received in public school systems.

The American South is deeply religious. In 1925, it was even more religious, plus it was still imbued with a sense of self-righteous indignation regarding its humiliation in the post-Civil War period. Not-for-nothing was the state’s most prominent populist politician, William Jennings Bryan, an observant Protestant who aided, incompetently, in the prosecution of John Scopes, brought down, figuratively and literally, by the more disciplined, learned attorney for the defense, Clarence Darrow, a giant of American juris prudence. Bryan was very smart, but he was product of a very different culture than Darrow, and he was very much out of his element in a trial that delved into the science of evolution.

The urban versus rural divide encompasses education and propensity for observance of religious dictates. That divide was definitely a part of the “Scopes Monkey Trial.” The disparities between cultures and exposures to schools of thought and academic disciplines was as much on trial as the issue of teaching evolution in public schools.

How many moles of `CO_2` are produced from `3` kg of `C_6H_(14)` completely burned?

`C_6H_(14)` is a hydrocarbon called hexane. When burned, it produces carbon dioxide `CO_2` and water `H_2O.`

To answer the question we need to write the balanced chemical reaction. It is

`2C_6H_14 + 19O_2 = 12CO_2 + 14H_2O.`

To obtain these coefficients, we first look at carbon, `6` at the left, and give `CO_2` the coefficient `6.` Then count `H,` `14` at the left, so `H_2O` must have the coefficient `7.` But then there will be even quantity of `O` at the left and odd at the right. This requires to change `7` at `H_2O` to `14,` `1` at `C_6H_14` to `2` and `6` at `CO_2` to `12.` Then the coefficient at `O_2` becomes `19.`

Now we see that `2` moles of `C_6H_14` make `12` moles of `CO_2,` so `1` mole makes `6.` The molar mass of hexane is `6*12+14*1=86 g/(mol).`

Finally, `3 kg` of hexane are `(3000 g)/(86 g/(mol)) approx 34.9` moles, so there will be about `34.9*6 approx 209` moles of `CO_2.`

What is typhoid fever?

Causes and Symptoms

Typhoid fever, a serious disease with the potential to become epidemic under conditions of poor sanitation, is caused by the bacterium Salmonella enterica, serotype Typhi (formerly Salmonella typhi). These bacteria are transmitted to humans through the consumption of water or food contaminated with the feces from individuals who carry the serotype Typhi but who most often remain asymptomatic.

An infective dose of bacteria in susceptible individuals is estimated to be quite small, generally less than one thousand cells. The ingested bacteria pass through the stomach to the small intestines, where they establish an initial site of infection. These intestinal lesions usually ulcerate, and the bacteria spread to other body tissues via the bloodstream and lymphatic system. The organs most often affected by these secondary infections include the liver, spleen, kidneys, bone marrow, and especially the gallbladder. Symptoms include headache, abdominal pain, general malaise, and a generalized rash with rose-colored spots. If no complications ensue, then the fever will abate after about three weeks, but mortality rates average about 15 percent in untreated cases.

Treatment and Therapy

The first drug with demonstrable effectiveness in treating typhoid fever was chloramphenicol, which became generally available in 1948. Other antibiotics, notably ampicillin and ciprofloxacin, have largely replaced chloramphenicol as the treatment of choice, and their use has reduced the death rate to approximately 1 percent. Improved sanitation and living conditions since the 1920s have drastically reduced the incidence of this disease in the United States, although worldwide it remains a major public health concern. The World Health Organization estimates that at least 16 million cases and more than 200,000 deaths can be attributed to typhoid fever each year.

Vaccines are available to prevent typhoid fever, but their effectiveness is suboptimal. Temporary immunity is acquired by about 60 to 75 percent of vaccinated individuals. Individuals who recover from the disease often become healthy carriers of the bacteria, and surgical removal of the gallbladder may be necessary to rid them of their carrier status.

Perspective and Prospects

The most famous case of a healthy carrier of the typhoid fever bacteria was a cook by the name of Mary Mallon, called “Typhoid Mary,” who worked in several establishments in New York during the period from 1902 to 1915. In those years, she was linked to several different outbreaks of typhoid fever, resulting in fifty-one cases of illness and three deaths. When she repeatedly refused to cooperate with public health authorities, she was eventually taken into custody and confined in a state hospital. After almost three years, she was released, but she soon skipped parole and disappeared. Four years later, she was apprehended again as the source of a typhoid fever outbreak that involved twenty-five cases and two deaths. She was returned to the secure hospital in 1915, where she remained until her death in 1938. The important legal issues generated by her case, including incarceration for having an infectious disease and forced surgery, were the driving forces behind the founding of the American Civil Liberties Union (ACLU).

Bibliography

Badash, Michelle, and Michael Woods. "Typhoid Fever." Health Library, Nov. 26, 2012.

"Diarrhoeal Diseases: Typhoid Fever." World Health Organization, Feb. 2009.

Lock, Stephen, John Last, and George M. Dunea, eds. The Oxford Companion to Medicine. 3rd ed. New York: Oxford University Press, 2006.

Murray, Patrick R., Ken S. Rosenthal, and Michael A. Pfaller. Medical Microbiology. 7th ed. Philadelphia: Mosby/Elsevier, 2013.

"Salmonella Infections." MedlinePlus, Apr. 19, 2013.

Tortora, Gerard J., Berdell R. Funke, and Christine L. Case. Microbiology: An Introduction. 11th ed. San Francisco: Pearson Benjamin Cummings, 2013.

"Typhoid Fever." Centers for Disease Control and Prevention, May 14, 2013.

Vorvick, Linda J., Jatin M. Vyas, and David Zieve. "Typhoid Fever." MedlinePlus, June 9, 2011.

What is croup?

Causes and Symptoms

Croup is an inflammation of the larynx, trachea, and upper bronchial tubes of the lungs affecting children between the ages of six months and five years. Two-year-olds seem to be the most commonly affected. The inflammation of the trachea causes a narrowing of the child’s already small airways, making breathing difficult. Technically, croup is a syndrome, or collection of symptoms associated with several different kinds of infections. These symptoms include hoarseness, a distinctive cough most often described as “barky” and noisy, and labored breathing known as stridor.

Croup occurs in three different forms. The first, viral croup, usually begins with a cold and is most commonly caused by parainfluenza viruses. Indeed, studies indicate that the parainfluenza viruses are responsible for about 70 to 75 percent of croup cases. Viral croup is often accompanied by a low-grade fever. A second type of croup is called spasmodic croup. This condition tends to occur with changes of the weather or the seasons, and the child does not usually run a fever. Allergies are often thought to be responsible for this kind of croup. A third, but rare, form is a bacterial infection caused by mycoplasma. This form can be very serious and is often identified by the extreme difficulty that the child experiences with breathing.

Studies indicate that attacks of croup most commonly occur in October through March and generally strike at night. In general, boys are somewhat more likely to be affected by croup than are girls.

A serious, but rare, condition known as epiglottitis
can sometimes be mistaken for croup. In this condition, the epiglottis, the flap that covers the windpipe during swallowing, becomes inflamed and swollen, potentially cutting off the child’s air supply. The symptoms of epiglottitis are similar to those of croup, but the child’s difficulty in breathing is much more severe, and the child will often run a high fever, drool, and be unable to make voiced sounds. Epiglottitis develops quickly; a child’s life can be in jeopardy in only a few hours. Consequently, this condition must be treated as an emergency, requiring hospital care.

Treatment and Therapy

A number of treatments are generally used to bring relief to the child suffering from viral or spasmodic croup. The use of a cool mist humidifier can ward off an attack in the child who exhibits a tendency toward developing croup. A mild attack can also be alleviated through use of the humidifier. If the attack of croup is well under way or if it is severe, however, a cool mist humidifier may not be adequate. Many doctors recommend that after an attack of croup, a cool mist humidifier should be run in the child’s room for the next three or four evenings. Another commonly used treatment is to take the child, properly dressed, outside at night. Usually the cold, damp air will soothe the child’s inflamed airways.

Still another technique reported to relieve the symptoms of croup is to fill the bathroom with steam by running a hot shower. Setting the child in the steam-filled room for fifteen to twenty minutes often eases the child’s breathing. The most successful use of this treatment requires that the child be held, not placed on the floor, because steam rises.

Neither cough syrups nor antibiotics are appropriate treatments for croup. Cough syrups prevent the expulsion of phlegm, while antibiotics have no effect on viral infections. Croup caused by mycoplasma, however, is treated with an antibiotic, generally erythromycin.

Pediatricians recommend that the child’s doctor be called in the event of a croup attack. Serious attacks are generally treated in a hospital emergency room. There, the child may be given cortisone by injection or by mouth. In addition, hospitals can administer breathing treatments.

Bacterial croup is also treated at a hospital with antibiotics and an oxygen tent as needed. Indeed, immediate emergency room treatment is called for if there is a whistling sound in the breathing that seems to grow louder, if the child does not have enough breath to speak, or if the child is struggling to breathe.

Perspective and Prospects

Accounts of croup can be found in medical literature dating back to the eighteenth century. Membranous croup, also known as diphtheria, was a great killer of children and adults alike in the past. Immunization made this kind of croup extremely rare, however, by the mid-twentieth century.

During the last quarter of the twentieth century, doctors continued to research the uses of corticosteroids in the treatment of croup, as well as the most effective way to deliver these drugs.

Bibliography:

American Medical Association. American Medical Association Family Medical Guide. 4th rev. ed. Hoboken, N.J.: John Wiley & Sons, 2004.

"Croup." Medline Plus, March 22, 2013.

Kliegman, Robert M., et al. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa.: Elsevier, 2011.

Nathanson, Laura Walter. “Coping with Croup.” Parents 70, no. 9 (September, 1995): 29–31.

Niederman, Michael S., George A. Sarosi, and Jeffrey Glassroth. Respiratory Infections. 2d ed. Philadelphia: Lippincott Williams & Wilkins, 2001.

Shelov, Steven P., et al. Caring for Your Baby and Young Child: Birth to Age Five. 5th ed. New York: Bantam Books, 2009.

Spock, Benjamin, and Robert Needlman. Dr. Spock’s Baby and Child Care. 9th ed. New York: Gallery Books, 2011.

West, John B. Pulmonary Pathophysiology: The Essentials. 7th ed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins, 2008.

Wood, Debra. "Croup (Laryngotracheobronchitis)." Health Library, September 10, 2012.

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

In what ways is Tybalt's death important in the development of the plot in Romeo and Juliet? How is the theme revealed through the climax?

Tybalt's death is essential to the remainder of the plot in Shakespeare's Romeo and Juliet. His death leads to two very important events. First, the fact that Romeo killed Tybalt forces the Prince to sentence Romeo to exile. Romeo is banished to Mantua. This is crucial as Friar Lawrence's message to Romeo about Juliet faking her death is delayed when Friar John is quarantined due to a plague threat. The only message which Romeo receives is from Balthasar, who tells him that Juliet is dead. Romeo, distraught, then plots his own suicide.

Second, Tybalt's death causes Lord Capulet to devise a "day of joy" to make up for the family's loss. He agrees to marry Juliet to Count Paris, even after qualifying Paris's request in Act I. He plans to marry Juliet and Paris in just two days' time. Juliet panics and seeks advice from the Friar, who gives her the potion which will render her lifeless for almost two days. When she awakens in the tomb, Romeo has already killed himself, so she takes his dagger and stabs herself.

The theme revolving around Tybalt's death involves fate. Romeo and Juliet are destined to commit suicide. Shakespeare announces this verdict in the Prologue: "A pair of star-crossed lovers take their life." Romeo is ruled by fate. He indicates this in his aside in Act I, Scene 4, after Mercutio's Queen Mab speech:

I fear too early, for my mind misgives
Some consequence yet hanging in the stars
Shall bitterly begin his fearful date
With this night’s revels, and expire the term
Of a despisèd life closed in my breast
By some vile forfeit of untimely death.

Romeo has already predicted his own death and the fight with Tybalt is simply the vehicle Shakespeare uses to fulfill this prophecy. Romeo realizes his folly immediately after Tybalt falls in Act III, Scene 1 when he says, "O, I am Fortune’s fool!" Tybalt's death puts in motion the tragic sequence which finds Romeo and Juliet dead in the Capulets' tomb at the end of the play.

What did Nat Turner do in the Civil War?

Nat Turner had been dead for nearly thirty years by the time the Civil War began in 1861. He was hanged in November of 1831 for his role in leading a large and violent slave revolt in Southampton County Virginia earlier in that year. While he obviously played no role in the Civil War, his revolt, which killed over 50 white people, heightened Southern fears about slavery, and especially about the abolitionist movement, which they deemed destabilizing to the institution. Turner's revolt led to a serious debate about emancipation and deportation of former slaves in the Virginia legislature. When emancipation measures were voted down, lawmakers instead attempted to place their enslaved population under even tighter control, banning private meetings among slaves (Turner was a lay Baptist minister) and restricting travel between plantations. Thus Turner's revolt led to increased tensions in the South between whites and their growing slave populations. These tensions made Southerners even more defensive when it came to what they saw as Northern threats to slavery and its expansion into the West, where many Virginians hoped to be able to sell their slaves.

What do Joey's comments tell us about him in Tangerine?

Joey’s comments tell us that, unlike his friend Paul, Joey is unwilling to embrace Tangerine Middle School’s diversity and adapt his attitude to its culture of sarcastic comments and tough-guy bravado.  

First, Joey says, “Theresa Cruz. Why? Is she cute or something?” when Paul tells him to ask for Theresa Cruz to be his guide on his first day of school at Tangerine. This shows that Joey doesn’t understand the importance of making connections, a skill that helped Paul quickly become part of the Tangerine community. Joey doesn’t see what Theresa Cruz has to offer him, beyond her physical appearance. Joey’s unable to meet the Tangerine students halfway by adjusting to their culture. He’s also unwilling to listen to Paul, who has become an expert on how to survive and thrive in Tangerine’s different school culture.

“That guy’s bad news. I don’t need this. I don’t need this at all,” Joey says when Paul puts himself and Joey into a group with Tino. Joey feels genuinely hurt by Tino’s comments, which include calling him “Tuna Boy” and making fun of his unwillingness to leave Paul’s side. While Paul underwent the same teasing without complaint, Joey can’t recognize that Tino makes friends through lighthearted insults. He only sees Tino’s comments as bullying, not as attempts to reach out.

“I let you talk me into coming to this dump. This place is like darkest Africa. Like the Amazon jungle. Like we’re learning to live among the natives here,” is Joey’s last comment before leaving Tangerine Middle School. This shows that Joey is completely fed up with Tangerine and willing to target his fellow classmates’ ethnicity in order to make himself feel superior.  The reader can also infer that Joey may have picked up racist language and thoughts from his parents or community. Again, the reader sees a differences between Paul and Joey. While Paul is happy to be at a diverse school that lets him meet people other than his own race, Joey sees Tangerine’s diversity as a flaw, not as something to celebrate.

Summarize the poem "Madam and Her Madam" by Langston Hughes.

In this humorous poem by poet Langston Hughes, a woman named Alberta, who works as a household servant, speaks in the first person about the duties she is required to perform for her employer, whom she calls "Madam." The speaker must clean the 12-room house, cook three meals a day, take care of the children, walk the dog, and do the laundry. The speaker confronts her employer about the enormous work load, asking her whether she is trying to make a "pack-horse" out of her. This question implies that the employer is taking advantage of Alberta, requiring her to do more work than is humanly possible or is kind.

The employer responds by denying the charge, and then professes her love for Alberta. In the humorous last stanza, Alberta acknowledges that her employer probably does love her, but that she does not return the sentiment. In fact, she says, "I'll be dogged if I love you." This is a euphemism and a slang term used for emphasis--there is no way an employee who is saddled with an impossible workload can be expected to love her oppressor.

One gets the impression that Alberta is a feisty and energetic woman who has been trying to do her best but finally comes to the conclusion that no matter how hard she tries, she will never be able to meet the unreasonable demands placed on her. The poem also fights against the stereotype of the cheerful black "help" on whom wealthy white women depended so that they would not have to lift a finger doing unpleasant tasks. This poem encourages overworked household staff to stand up for themselves and be honest about their limits and their feelings.

What is over-the-counter drug abuse?

Causes

OTC medications are readily obtainable, making them easy to abuse. Also, these substances are difficult to detect in urine drug tests, which allows for abuse without consequences at school or work. The most commonly abused OTC drugs include cough syrup, cold medications, and antihistamines. Other OTC medications of abuse include sleep aids, herbal supplements, steroids, and aspirin and other pain relievers.

The main ingredient of abuse in cough and cold medications is dextromethorphan hydrobromide (DXM), which causes hallucinations at high doses, but the other ingredients in cough medicines such as acetaminophen and pseudoephedrine can lead to fatal overdoses when taken at high levels. Additionally, 5 percent of persons of Caucasian ancestry are unable to metabolize DXM properly, which causes a buildup of toxic levels of the substance and causes more severe drug effects.

Diphenhydramine is a common antihistamine that is often abused for its sedative effects. Diphenhydramine can compound the sedative properties of anti-anxiety medications, particularly benzodiazepines, and abusers often take these drugs in combination to increase their high.

Risk Factors

Persons who abuse OTC medications are most often Caucasian females, although all ethnicities, ages, and genders abuse these drugs. Adolescents are at particularly high risk because the substances are easy to obtain. Substance abusers often seek OTC drugs when they are unable to acquire other illegal drugs or alcohol. Persons with a psychiatric diagnosis also are at greater risk, and those who are suicidal are more likely to use OTC medications with alcohol to attempt suicide. Medical personnel have an increased risk for antihistamine abuse because these medications are easily accessible at their place of employment.

Symptoms

OTC medications cause different symptoms when they are used according to the drug’s label than when they are abused, or used off-label. Also, each OTC medication has a different set of effects. For example, cold and cough medications are intended to act as decongestants and cough suppressants. When taken in high doses, the DXM in these medications acts like the illegal drugs phencyclidine (PCP) and ketamine. DXM, PCP, and ketamine cause euphoria, hallucinations, dissociation, and psychosis. The stimulants in many of these medications can lead to prolonged sexual performance and erection, but also to agitation, priapism, and dangerous elevations in heart rate.

Antihistamines are used to treat the symptoms of allergic reactions. The symptoms of antihistamine abuse include dizziness, loss of coordination, drowsiness, dry mouth, headaches, and stomach pain. Using high doses of antihistamines in combination with alcohol can cause nausea, heart palpitations, and liver damage.

Dietary supplements and herbal medications can cause psychosis when taken in large quantities. The misuse of sedatives may induce coma, and steroid abuse may cause aggressive behavior.

Screening and Diagnosis

Emergency physicians often do not inquire about what OTC medications a patient is taking or the reasons why he or she is using them. Therefore, OTC abuse is often identified only during a regular medical appointment or during a mental health screening. Many of the OTC medications will not appear on a routine urine drug test, but abuse of DXM at high doses may cause a drug screen to be abnormal for PCP.

Treatment and Therapy

Symptoms of withdrawal have been reported with OTC abuse and differ based on the specific medication used. As with many substances of abuse, a gradual tapering of the OTC medication may help with the process of detoxification and may minimize withdrawal symptoms. Persons who have an addiction may be referred to Pills Anonymous to complete a twelve-step, group therapy program, which is similar to the programs of Alcoholics Anonymous or Narcotics Anonymous. Outpatient or inpatient therapy for substance abuse is also available, although often underutilized for OTC abuse.

Prevention

Supermarkets and pharmacies have started to enforce stricter policies regarding the purchase of many OTC medications. While cold, cough, and allergy medications traditionally have been found in the aisles of stores, many are now located behind the counter of a store’s pharmacy and require proof of legal age (eighteen years) to purchase. Also, there are limits to the number of packages of medications a customer can purchase per day. While these are not foolproof methods to reduce OTC medication abuse, they do make it more difficult for minors to abuse OTCs and for any person to obtain large quantities of the substances at one time. For adolescents, parental education and awareness about OTC medication abuse has been demonstrated to successfully reduce the problem of OTC abuse.

Bibliography

Cohen, Michael R. "10 Over-the-Counter Medicines Abused by Teens." Philly.com. Philadelphia Media Network, 17 Oct. 2013. Web. 27 Oct. 2015.

Gracious, Barbara, Naomi Abe, and Jane Sundberg. “The Importance of Taking a History of Over-the-Counter Medication Use: A Brief Review and Case Illustration of ‘PRN’ Antihistamine Dependence in a Hospitalized Adolescent.” Journal of Child and Adolescent Psychopharmacology 20.6 (2010): 521–24. Print.

Lessenger, James, and Steven Feinberg. “Abuse of Prescription and Over-the-Counter Medications.” Journal of the American Board of Family Medicine 21 (2008): 45–54. Print.

"Mixing Alcohol with Medicines." National Institute on Alcohol Abuse and Alcoholism. NIH, 2014. Web. 27 Oct. 2015.

National Survey on Drug Use and Health. “Characteristics of Primary Prescription and OTC Treatment Admissions, 2002.” Washington: SAMHSA, 2004. Print.

Where is the speaker when he or she hears lake water lapping?

According to the author of this poem, William Butler Yeats, this poem is autobiographical, so we know the speaker is the poet himself. Yeats explained that when he was in his early twenties, he was on a sidewalk in London when he passed by a shop that had a display containing a jet of water that squirted up and balanced a little ball on top of the water stream. The sound of running water reminded him of time in his childhood that he spent in County Sligo in Ireland by the shores of a beautiful lake there, Lough Gill. That incident was his inspiration for writing the poem.

In the text of the poem, the speaker says that when he is "on the roadway, or on the pavements gray," he hears in his imagination the sound of the waves gently coming in to shore. To most Americans, this sounds like the speaker is on a paved street. However, in British usage, as well as in some Atlantic states in the U.S., "pavement" means "sidewalk." You may be familiar with the idiom "to pound the pavement," which means to walk from business to business searching for sales or employment, usually on a sidewalk. 

The fact that the speaker hears the "lake water lapping" even though he is in the city and far from the lakeside country that he misses emphasizes the speaker's intense longing for his isolated island retreat. The speaker would no doubt be able to hear the "low sounds by the shore" no matter what his location was because the desire to go there was so entrenched within him that he could "hear it in the deep heart's core." 

What is an organ in anatomy?

In anatomy, an organ is a quantity of tissue that has formed into an organized collection of cells in order to cooperatively perform an overall function. Both plants and animals can have organs; the study of plant organs is referred to as plant morphology, while the study of animal organs is known as anatomy. A single organ is also known as a viscus (plural viscera).

Some organs, such as the liver, are solid masses of tissue. Other organs, such as the heart and the stomach, have one or more cavities inside. These cavities are typically used to transport material throughout the organism, as when the heart’s chambers circulate blood or the stomach receives food and transfers it to the intestines.

Background

The word “organ” is derived from Latin and Ancient Greek, where it originally meant “instrument” in the sense of a thing that performs a function, not unlike a tool or even a musical instrument. While organs exist as independent entities within the organism, they often are part of larger organ systems that are composed of several interrelated yet distinct organs, each performing separate but complementary functions. For example, the digestive system is an organ system that includes the stomach, the small intestine, the large intestine, the liver, and the pancreas, among other organs. Each organ works with the other members of the system to accomplish the overall goal of acquiring nutrients for the body’s sustenance.

Overview

Anatomy, or the study of the body’s parts and their functions, has a long and colorful history. Anatomy can be thought of on two different scales: gross (or macroscopic) anatomy, which refers to the study of organs and organ systems with the unaided eye, and microscopic anatomy, which is the study of organs using microscopes and other means of ocular amplification.

In ancient Egypt, it was thought that organs either performed certain functions or pertained to specific deities, and Egyptians believed that organs needed to be preserved for use in the afterlife, just like the bodies they mummified. When an individual died, the body’s organs were stored in canopic jars within the burial chamber. Each organ was kept in a jar carved in the likeness of the god to whom it pertained. For example, the stomach was kept in a jar that resembled the god Duamutef, distinctive for his jackal-like head.

Throughout history, different cultures have developed associations between organs and specific personality traits. The most common example is the modern association of the heart with love, passion, and intense emotion. The association between love and the human heart is seen in such traditions as wearing a wedding ring on the ring finger of the left hand; it was once believed that the vena amoris (literally, “vein of love” in Latin) ran directly from the heart to this finger. All fingers on both hands, however, share the same type of vein structure. Similarly, the brain is often viewed as the seat of consciousness, and there is frequent philosophical disagreement about whether the soul resides in the brain, the heart, or somewhere else entirely. The eyes are sometimes considered the “windows to the soul,” and the digestive organs have even been linked to subconscious intuition, such as having a “gut feeling” about someone or something.

Many cultures, including the Greeks, Romans, Etruscans, Babylonians, Assyrians, and Hittites, practiced a form of augury, or fortune-telling, known as haruspicy. In this ritual, a haruspex would sacrifice an animal and then look at the condition, position, and other characteristics of its internal organs (usually the intestines) in order to foretell what would or would not happen in the future.

Long ago, the only way for scientists and physicians to study organs was to have access to a corpse, which was challenging due to religious and cultural taboos pertaining to death and decay. Only in the twentieth century did technologies such as the x-ray, magnetic resonance imaging (MRI), ultrasound, and positron emission tomography (PET) scanning allow physicians and scientists to noninvasively observe and study functioning organs in a live patient. It is even possible to observe what parts of the brain become more neurochemically active in response to stimuli such as flashing lights, which helps scientists understand what sections of the brain are responsible for particular types of information processing (long-term memory, short-term memory, sensory stimulation, emotion regulation, and so forth).

Science has also advanced make organ transplantation possible. A functioning and healthy organ is removed from one body and is surgically inserted (transplanted) into the body of another patient, whose original organ has either been damaged or suffered from a defect that prevented it from operating appropriately. It is possible to transplant entire organs as well as tissue such as skin or bone marrow. In a few cases it is possible for a living person to donate tissue or an organ—a healthy person has two kidneys, for example, but can live with only one—but most organ donors are either brain-dead or recently deceased.

A frequent problem with organ transplant procedures is organ rejection, in which the recipient’s body rejects the donated organ as an intrusion and treats it as an invasive disease, causing the immune system to attack the newly received organ or tissue. Doctors continue to study how organs operate so they can work to suppress this immune response and thereby increase the likelihood of success in organ-transplant procedures.

Bibliography

Ferber, Sarah, and Sally Wilde, eds. The Body Divided: Human Beings and Human “Material” in Modern Medical History. Burlington: Ashgate, 2011. Print.

Hamilton, David. A History of Organ Transplantation: Ancient Legends to Modern Practice. Pittsburgh: U of Pittsburgh P, 2012. Print.

Healey, Justin, ed. Organ and Tissue Donation. Thirroul: Spinney, 2011. Print. Issues in Soc. 333.

Klein, Andrew A., Clive J. Lewis, and Joren C. Madsen, eds. Organ Transplantation: A Clinical Guide. New York: Cambridge UP, 2011. Print.

Kliegel, Ewald. Let Your Body Speak: The Essential Nature of Our Organs. Illus. Anne Heng. Trans. Sabine Weeke. Forres: Findhorn, 2013. Print.

Le, Tao, et al. First Aid for the Basic Sciences: Organ Systems. 2nd ed. New York: McGraw, 2012. Print.

Patton, Kevin T, and Gary A. Thibodeau. Anthony’s Textbook of Anatomy & Physiology. 20th ed. St. Louis: Mosby, 2013. Print.

Trzepacz, Paula T., and Andrea F. DiMartini. The Transplant Patient: Biological, Psychiatric and Ethical Issues in Organ Transplantation. Cambridge: Cambridge UP, 2000. Print.

Widmaier, Eric P., Hershel Raff, and Kevin T. Strang. Vander’s Human Physiology: The Mechanisms of Body Function. 13th ed. New York: McGraw, 2014. Print.

What is Japanese encephalitis?

Definition

Japanese encephalitis is a mosquito-borne virus that leads to swelling of the brain. It can affect the central nervous system and cause severe complications, even death.

Causes

Japanese encephalitis is caused by the bite of a mosquito infected with the virus.

Risk Factors

The factors that increase the chance of being exposed to Japanese encephalitis
include living or traveling in certain rural parts of Asia. According to the
Centers for
Disease Control and Prevention, outbreaks of Japanese
encephalitis have occurred in China, Korea, Japan, Taiwan, and Thailand. These
countries have controlled the disease through vaccinations. Other countries that
still have periodic epidemics include Vietnam, Cambodia,
Myanmar, India, Nepal, and Malaysia. Also, laboratory workers who might be exposed
to the virus are at high risk for developing Japanese encephalitis.

Symptoms

Symptoms of Japanese encephalitis, which usually appear five to fifteen days after the bite of an infected mosquito, include agitation, brain damage, chills, coma, confusion, convulsions (especially in infants), fever, headache, nausea, neck stiffness, paralysis, tiredness, tremors, and vomiting.

Screening and Diagnosis

A doctor will ask about symptoms and medical history and will perform a
physical exam. Tests may include blood tests to look for antibodies, a
magnetic
resonance imaging (MRI) scan (a scan that uses radio waves
and a powerful magnet to produce detailed computer images), a computed tomography (CT)
scan (a detailed X-ray picture that identifies abnormalities
of fine tissue structure), and cerebrospinal fluid tests.

Treatment and Therapy

Because there is no specific treatment for Japanese encephalitis, care is concentrated on treating specific symptoms and complications.

Prevention and Outcomes

A Japanese encephalitis vaccine is recommended for people who live or travel in certain rural parts of Asia and for laboratory workers who are at risk of exposure to the virus. Also, to protect against mosquito bites and to prevent the disease, one should remain in well-screened areas, wear clothes that cover most of the body, and use on skin and clothing those insect repellents that contain up to 30 percent NN-diethyl metatoluamide (DEET).

Bibliography

Booss, John, Margaret Esiri, and Margaret M. Esin, eds. Viral Encephalitis in Humans. Washington, D.C.: ASM Press, 2003.

Centers for Disease Control and Prevention. “Japanese Encephalitis.” Available at http://www.cdc.gov.

EBSCO Publishing. DynaMed: Japanese Encephalitis. Available through http://www.ebscohost.com/dynamed.

Goddard, Jerome. Physician’s Guide to Arthropods of Medical Importance. 4th ed. Boca Raton, Fla.: CRC Press, 2003.

Marquardt, William C., ed. Biology of Disease Vectors. 2d ed. New York: Academic Press/Elsevier, 2005.

National Institute of Neurological Disorders and Stroke. “Meningitis and Encephalitis Fact Sheet.” Available at http://www.ninds.nih.gov.

Peters, C. J. “Infections Caused by Arthropod- and Rodent-Borne Viruses.” In Harrison’s Principles of Internal Medicine, edited by Anthony Fauci et al. 17th ed. New York: McGraw-Hill, 2008.

United Nations International Children’s Emergency Fund. “Vaccine Is Key to Preventing Outbreaks of Japanese Encephalitis.” Available at http://www.unicef.org/infobycountry/india_28555.html.

What are some examples of allusion in Fahrenheit 451 by Ray Bradbury?

An allusion is when an author makes a reference to an outside source that the reader might know about. Allusions can be historical, mythical, political, etc. This helps the reader make a mental connection from the outside world to a message that the author wants to send. In Bradbury's Fahrenheit 451, many different types of allusions can be found. One allusion that Captain Beatty uses is about the Pierian spring, which is known as a fountain of knowledge. Beatty actually quotes Alexander Pope by saying the following:

"A little learning is a dangerous thing. Drink deep, or taste not the Pierian spring; There shallow draughts intoxicate the brain, and drinking largely sobers us again" (106).

The above passage shows Beatty making an allusion to Pope, who makes an allusion to the Pierian spring. If readers follow the line of thinking in the quote, then they will understand the connection between the spring of knowledge and what is going on with Montag in the story.

Another allusion is when Captain Beatty reacts to Montag returning to the firehouse after taking a day or two off to explore books. Beatty says, "Well... the crisis is past and all is well, the sheep returns to the fold. We're all sheep who have strayed at times" (105). When Beatty mentions sheep, he is alluding to the Bible and the parable that mentions returning a sheep to its fold. Readers who know this would make the connection that Beatty sees Montag as a sheep returning to his fold—the firemen at the firehouse.

One final example of an allusion is the one Granger mentions about a phoenix. The city Montag escapes from is blown up by an atomic bomb. Granger hopes humanity will recover from this catastrophe like a phoenix who is reborn from the ashes of fire. Granger explains as follows:

"There was a silly damn bird called a phoenix back before Christ, every few hundred years he built a pyre and burnt himself up. . . But every time he burnt himself up he sprang out of the ashes, he got himself born all over again. And it looks like we're doing the same thing" (163).

After an atomic bomb levels the city, that city is probably smoldering with coals and ashes. This helps to provide a mental image for the reader about what Montag and the other men see in the aftermath. The allusion to the phoenix also gives readers hope that maybe humanity will be reborn and be able to rebuild a better society than what Montag lived in.

What is the Stanford-Binet test?

Introduction

The origin of the idea that intelligence could be tested can be found as early as the 1860’s, following the publication of British naturalist Charles Darwin’s work On the Origin of Species by Means of Natural Selection (1859). Among the concepts addressed in this book, and in his later The Descent of Man (1871), was the idea that the intelligence of animals, including man, could be understood and measured through scientific investigation.

Sir Francis Galton, a British scientist and explorer, who was also Darwin’s cousin, was among the first to adopt Darwin’s ideas for testing. Galton maintained a laboratory in London, England, where visitors could undergo assorted physical or sensory tests. A subject could be observed on the basis of, for instance, ability to interpret musical pitch. Galton believed such physical or sensory abilities reflected intelligence.

The Binet-Simon Test

In 1904, the Commission for the Education of Retarded Children was established in Paris, France, for the purpose of developing a test that could accurately measure levels of intelligence. The concern was that children were being labeled as what was then termed "retarded" not on the basis of mental capacity but because of behavioral problems. An intelligence test could be used to avoid such incorrect labeling.

Alfred Binet believed that what was recognized as intelligence actually represented a combination of factors, including both knowledge gained from school and knowledge obtained from general observations and interactions with others. The Stanford-Binet test represented the first attempt at determining the mental age of a subject as a means of separating children with learning disabilities from those who did not suffer from learning problems. The basis of such testing consisted of a series of mental tasks of increasing difficulty. Children of various ages were assumed to have a certain level of knowledge in dealing with such tasks. The number of correct responses to these questions resulted in the assignment of a certain “mental age” to the child.

As originally developed in 1905 by Binet and his colleague Théodore Simon, the test, known as the Binet-Simon test, consisted of thirty tasks that ranged from manual dexterity to the ability to remember general facts or concepts. Binet initially screened fifty children considered of average intelligence and developed a series of norms, now called the 1905 scale. Children were tested in this manner and received a score reflecting what Binet and Simon considered their mental age.

Terman’s Refinements

In 1912, psychologist William Stern adapted Binet’s work by calculating what became known as the intelligence quotient, or IQ. The IQ score was calculated by dividing the mental age by the chronological age and multiplying by 100. For example, a mental age of ten and a chronological age of ten resulted in an IQ of 100, considered average. A mental age of twelve in a child of ten would result in an IQ of 120, considered somewhat above average.

Experience with administration of the test to thousands of children over many decades has demonstrated that the distribution of scores resembles a symmetrical pattern, a normal distribution or bell-shaped curve. Most children (approximately two-thirds) fall within the middle of the curve, with the remaining children distributed more or less equally in higher or lower ranges.

The test as originally devised by Binet consisted primarily of verbal reasoning, reflecting the purpose of the test as a means to separate children with learning disabilities from those without. In 1916, Lewis Terman of Stanford University increased the length of the test and extended the range of age among the children who served as subjects. The result was the normal distribution of scores that is now characteristic of the results. What now became known as the Stanford-Binet test replaced its predecessor, the Binet-Simon. Terman’s adaptation has undergone several revisions in the ensuing decades.

The most recent version of the Stanford-Binet test, developed in 2003, consists of both verbal and nonverbal items. The verbal portion involves asking the child to explain or define the use of specific objects. The nonverbal portion contains questions that attempt to examine concepts such as quantitative and abstract reasoning, and memory.

Bibliography

Binet, Alfred, and Théodore Simon. The Development of Intelligence in Children. 1916. Reprint. Manchester, N.H.: Ayer, 1983. Print.

Flannagan, Dawn P., and Patti L. Harrison, eds. Contemporary Intellectual Assessment: Theories, Tests, and Issues. 3rd ed. New York: Guilford, 2012. Print.

Gould, Stephen Jay. The Mismeasure of Man. Rev. ed. New York: W. W. Norton, 2008. Print.

Hernnstein, Richard, and Charles Murray. The Bell Curve. New York: Simon & Schuster, 1996. Print.

Kaplan, Robert M., and Dennis P. Saccuzzo. Psychological Testing: Principles, Applications, and Issues. 8th ed. Belmont: Wadsworth, 2013. Print.

Minton, Henry L. Lewis M. Terman: Pioneer in Educational Testing. New York: New York University Press, 1990. Print.

Musso, Mandi W., et al. "Development and Validation of the Stanford Binet-5: Rarely Missed Items and Nonverbal Index for the Detection of Malingered Mental Retardation." Archives of Clinical Neuropsychology 26.8 (2011): 756–67. Print.

Naglieri, Jack A., and Sam Goldstein, eds. Practitioner’s Guide to Assessing Intelligence and Achievement. Hoboken, N.J.: Wiley, 2009. Print.

What is Corynebacterium?

Definition

Corynebacterium is a gram-positive, non-spore-forming rod with a
characteristic club-shaped appearance and worldwide distribution. C.
diphtheriae is a major human pathogen.

Natural Habitat and Features

Corynebacterium spp. are gram-positive, nonmotile, catalase-positive rods. Along with the Mycobacteria and Nocardia, they produce characteristic long-chain mycolic acids that can be used in their taxonomy. Their metabolism is varied, with both aerobic and facultatively anaerobic members of the genus. Those with anaerobic metabolism usually perform lactic acid fermentation. The bacteria are fastidious, and all strains require biotin and most require several other supplements. They are usually grown under an enriched carbon dioxide atmosphere and grow slowly, even on complex-enriched culture media.

The rods are pleiomorphic, some having club-shaped ends (the Greek word koryne means “club”), and often show incomplete separation during cell division. This has led some scientists to note their resemblance to Chinese characters. The incomplete separation is caused by a characteristic “snapping” cell division, which leads to their peculiar cell wall. The main wall constituent is commonly called mycolyl-AG-peptidoglycan and is made up of high-diaminopimelic-acid peptidoglycans, arabinoglactans, and mycolic acid, all connected through disaccharide linkages. During cell division, the plasma membrane divides normally, but the cell wall may only partially separate, forming V- and other odd-shaped assemblages of two or more cells.

The genomes of three species have been sequenced and contain a single circular chromosome of about 2.5 million base pairs with a high G-C content (53.5 percent). The taxonomy of Corynebacterium is based on genomic deoxyribonucleic acid (DNA), 16-s ribonucleic acid (RNA), and cell wall lipids. A major taxonomic realignment was made in the 1990’s. Some former Corynebacterium spp. have been moved to other related genera:C. acnes to Propionobacterium acnes and C. hemolyticum to Arcanobacterium hemolyticum. Other bacteria were added to Corynebacterium: For example, the JK bacterial group became C. jeikeium.

Many Corynebacterium spp. have industrial applications,
producing complex organic nutritional factors and medically important compounds.
They degrade hydrocarbons and age cheese. Arguably the most important of these
species is glutamicum, which is the primary source of the food
additive monosodium glutamate (MSG) and has been genetically
engineered to produce human epiderman growth factor, among other applications.
Corynebacterium spp. have a worldwide distribution, especially
in temperate areas, and are found in soils and water and in and on animals and
plants.

Pathogenicity and Clinical Significance

Diphtheriae is the most important corynebacterial pathogen of
humans and causes diphtheria. This disease is an upper respiratory infection
with a characteristic pseudomembrane that covers parts of the pharynx and adjacent
areas. Diphtheriae to epithelial cells at the site of infection,
causing them to produce the fibrin-based pseudomembrane. The toxin can also be
disseminated to many other areas of the body, leading to possible organ
failure.

Only those strains with an integrated lysogenic phage that carries the gene for the diphtheria toxin are able to produce the toxin. The disease severity is often a consequence of the strain of diphtheriae that causes the infection, because different strains grow at different rates and produce different amounts of diphtheria toxin. The toxin regulatory gene (DtxR), located on the bacterial chromosome, also affects toxin levels. Iron serves as the corepressor of DtxR’s product, so under normal iron concentrations, toxin production is greatly curtailed. Under iron starvation, toxin production is dramatically increased.

Diphtheriae also can cause cutaneous diphtheria, a skin infection, if it enters a break in the skin. In rare instances, it also can cause genital and eye infections.

Nonpathogenic Corynebacterium are often referred to as
diphtheroids, however, many of them can be opportunistic pathogens, especially in
the elderly, the immune compromised, and those with prosthetic devices.
Bovis and ulcerans have been isolated from
skin ulcers, and bovis and pyogenes have caused
systemic bacteremia. Corynebacteria that have been isolated from
other infections include xerosis, jeikeium,
striatum, and pseudodiphtheriticum. Many
other diphtheroids, found as commensal organisms on healthy persons, might become
pathogenic under the right circumstances.

Drug Susceptibility

Treatment of diphtheria is two-pronged. Diphtheria antitoxin, produced in horses, is used to neutralize the toxin;
antibiotics are used to kill the bacteria. The antibiotics
of choice are penicillin and erythromycin, administered for fourteen days.
Clindamycin, rifampin, and tetracycline can also be used. Antibiotic
susceptibility of the diphtheroids varies, but penicillins, erythromycin, and
rifampin are usually good choices. Penicillin resistance has been seen in some
nontoxigenic diphtheriae strains.

Bibliography

Burkovski, Andreas, ed. Corynebacteria: Genomics and Molecular Biology. Norfolk, England: Caister Academic Press, 2008. This book mainly focuses on C. glutamicim. Chapter 2, however, discusses the genomics of many Corynebacterium spp.

Guilfoile, Patrick G. Deadly Diseases and Epidemics: Diphtheria. New York: Chelsea House, 2009. This volume describes diphtheria in detail.

Krieg, Noel R., et al., eds. Bergey’s Manual of Systematic Bacteriology. 2d ed. New York: Springer, 2010. Volume 5 of this multivolume work describes Corynebacterium and its relatives in detail.

Madigan, Michael T., and John M. Martinko. Brock Biology of Microorganisms. 12th ed. Upper Saddle River, N.J.: Pearson/Prentice Hall, 2010. This text outlines many common bacteria and describes their natural history, pathogenicity, and other characteristics.

What is necrotizing fasciitis?

Causes and Symptoms

Although it had been identified in the past, in 1994 there were numerous headline newspaper reports describing a new
“flesh-eating bacteria.” These articles detailed the devastating effect of seemingly minor wounds infected with streptococcal bacteria. Patients quickly become very sick, with a rapidly progressive downward course, even from trauma resulting in a deep muscle bruise or muscle strain or in “minor” cuts and scrapes.

In the former nonpenetrating injuries, it is likely that the bacteria were already present in the blood and then seeded the site of damage. Most of these patients, however, did not recall any prior recent infection that may have made them susceptible. Penetrating injuries, where the normally protective barrier of the skin has been broken, were often minor and not originally treated as contaminated or infected. Other cases of necrotizing fasciitis are caused by surgical infections and bowel contamination. These cases are more rare and often found to have a mixture of bacteria, such as staphylococci or Escherichia coli (E. coli).

Patients with necrotizing fasciitis have fever, inflammation, severe pain, and blistering at the site of infection. If this cellulitis is not recognized and urgently treated, the infection will quickly spread in the layers of connective tissue just under the skin known as the fascia. As the bacteria multiply, they cause blood vessels supplying the skin to form clots and thus cut off blood flow to the skin. Without nutrients, oxygen, and the ability to remove waste products, the skin dies. Once this occurs, the nerves are destroyed and the patient no longer has the excruciating pain. The skin at this point appears to be “eaten away.” The possibility exists that the underlying muscle adjacent to the fascia will become infected. Thus, the potential for muscle death as well as skin death is of great concern, particularly if the infection begins in the arms, legs, abdomen, or back, as these areas have large muscle groups directly underlying the skin. In necrotizing fasciitis, the extremities and the area around the genitals and anus (perineum) are most commonly and extensively involved. Multiplication and movement of these streptococcal bacteria and their toxins into the bloodstream produces a shock-like state.

Treatment and Therapy

The patient with necrotizing fasciitis must be stabilized quickly in an intensive care unit, where fluids can be administered and heart and lung condition can be closely monitored. The only lifesaving treatment available is extensive surgical debridement to remove the necrotic (dead) tissue and slow the spread of the bacteria. Antibiotics including penicillins, clindamycin, and gentamicin are given to help eradicate the pathogen. Because the infection spreads so rapidly, death often results even with heroic surgical and drug therapy unless the condition is diagnosed and treated early. Fortunately, these infections remain relatively rare.

Bibliography

Berman, Kevin. "Necrotizing Soft Tissue Infection." MedlinePlus, November 22, 2011.

Biddle, Wayne. A Field Guide to Germs. 3d ed. New York: Anchor Books, 2010.

Forbes, Betty A., Daniel F. Sahm, and Alice S. Weissfeld. Bailey and Scott’s Diagnostic Microbiology. 12th ed. St. Louis, Mo.: Mosby/Elsevier, 2007.

MedlinePlus. "Streptococcal Infections." MedlinePlus, May 7, 2013.

Roemmele, Jacqueline A., and Donna Batdorff. Surviving the Flesh-Eating Bacteria: Understanding, Preventing, Treating, and Living with the Effects of Necrotizing Fasciitis. Garden City Park, N.Y.: Avery, 2000.

Snyder, Larry, et al. Molecular Genetics of Bacteria. 4th ed. Washington, D.C.: ASM Press, 2013.

Wilson, Brenda A., Abigail A. Salyers, et al. Bacterial Pathogenesis: A Molecular Approach. 3d ed. Washington, D.C.: ASM Press, 2011.

Wilson, Michael, Brian Henderson, and Rod McNab. Bacterial Disease Mechanisms: An Introduction to Cellular Microbiology. New York: Cambridge University Press, 2002.

In "To Kill a Mockingbird," why can't Walter Cunningham pass the first grade?

The reason Walter Cunningham can't pass the first grade has a lot to do with his background. In the novel, when Miss Caroline's good deed falls flat, Scout explains that Walter is a Cunningham and that he comes from a proud family, even if he is poor. In other words, the Cunninghams don't take gifts lightly; they always pay for what they use. If they can't pay for it, they go without. This is why Walter refuses to take Miss Caroline's money to pay for a lunch he cannot afford.

Atticus tells Scout that Mr. Cunningham often pays him in produce and other gifts because he is cash poor. Because Walter often has to help his father in the fields, he has little time to concentrate on his studies. We get the idea that education takes a back seat to temporal and practical matters in the Cunningham household. The Cunninghams are more concerned about surviving hard times than in receiving an adequate education.

In fact, Mr. Cunningham himself is said to have trouble signing his name. With such an example, Walter can't help but harbor similar nonchalance towards his own studies. At dinner with the Finches one day, he assures Atticus that, even though he has to help his father with the crops every spring, "there’s another’n at the house now that’s field size.” This possibly means that one of Walter's siblings will soon be able to help out in the fields, providing Walter the extra time he needs to devote to his studies.

What is organ donation?

Organ donation is a medical process in which tissue or an organ from a living or dead individual is transplanted to another individual. Advancements in modern medicine have made it possible to transplant a variety of organs and tissues, including the heart, lungs, liver, kidneys, intestines, pancreas, eyes, skin, bone, and tendons. Some organs, or parts of organs, can be transplanted from living hosts, while many other transplanted organs are obtained from recently deceased bodies.

The United States uses an "opt-in" system for organ donation in which individuals must explicitly volunteer to allow their organs to be donated after death, while other nations use an "opt-out" system in which all individuals are considered organ donors unless they explicitly state that they do not wish their organs to be donated. Individuals who wish to become living donors or to donate organs and/or tissues after death can register this preference with state agencies and with a variety of private medical organizations that link donors with medical institutions and potential recipients.

Brief History

Organ and tissue transplantation is the process of harvesting organs or tissues from the body of one individual and medically transplanting the tissues into the body of another individual. Transplanted organs can be used to help patients whose organs have been damaged due to injury or disease. American plastic surgeon Dr. Joseph Murray conducted the first organ transplantation in 1954—a kidney transplanted between identical twins—and later won the Nobel Prize in medicine for his discovery. Since the 1960s, advances in surgical techniques and technology have made it possible to transplant a variety of different types of tissue, including the heart, lungs, liver, kidneys, bones, veins and arteries, skin, and eyes.

The human body has a tendency to reject tissue transplanted from another body, owing to the immune system, which identifies the foreign tissue as a potentially harmful agent. To combat this, scientists have developed what are called "anti-rejection" medicines that lower the immune system response and allow the patient’s body to more readily adjust to the presence of foreign tissue. To reduce the risk of rejection, physicians use factors such as blood type and the presence or absence of certain types of immune system proteins to match organs and tissues with potential hosts.

Organs can be taken from living bodies or from the bodies of the recently deceased. Living donors can donate parts of organs like the liver, pancreas, skin, intestines, or a lobe of a healthy lung. The most common living donation is the kidney , because a healthy individual with two functional kidneys can donate one kidney without serious risk to their health. Living donation is often more successful than donations from deceased individuals, because the tissue is active and healthy at the time of transplantation.

Organs and tissues can also be taken from dead bodies, though this process is time-sensitive, because organs will begin to decay and lose viability for transplantation as soon as death occurs. As the time between death and transplantation is sensitive, transplantation science depends on the ability to quickly harvest and transport organs from deceased individuals.

Organ Donation in the United States

As of 2015, the United States utilizes an "opt-in" system in which individuals must consent to donate organs after their death. In some cases, an individual’s immediate family can consent to donate the deceased individual’s organs. The United States has the fourth highest organ donation rate in the world (26 donors per million individuals), and it is the leader in transplantation operations, with more transplants performed annually than in any other nation.

The laws involving organ donation and the procedure for registering as a potential organ donor differ between states. The US Department of Health and Human Services provides links through their website to help individuals determine the relevant authorities in each state to help them register as an organ donor. A number of states have integrated organ donation with driver’s and nondriver’s licensing procedures. For instance, in the state of Pennsylvania, individuals obtaining official state identification can give consent to donate organs or tissues and the label "organ donor" will be printed on the front of the state-issued identification card.

Spain is the global leader in organ donation, with every 35.3 per 1 million people listed as an organ donor. Unlike the United States, Spain has an "opt-out" policy, in which every individual is considered an organ donor unless they specifically choose to opt out of the system. Creating an opt-out system thus creates a larger pool of potential donors and eliminates situations where an individual might have chosen to donate an organ or tissue but died before having the chance to opt in to the system. However, opt-out systems are controversial, because some feel that organ donation is a personal decision and that individuals should not need to decline in order to control the use of their body tissues.

Need for Donation

In most countries, the number of patients waiting for organ donation far exceeds the number of potential and available donors. In the United States, a new patient is added to state organ transplant lists every ten minutes, and an average of seventy-nine people receive an organ transplant each day. In addition, an average of twenty-one people die each day while on the organ donation waiting list because of the scarcity of available organs. The US Department of Health and Human Services estimates in 2015 that more than 123,300 patients are waiting for an organ.

A recent controversy involves the potential for using social media and social capital to find organ donors. In 2015, thirty-nine-year-old Belgian car salesman Roel Marien posted a message on Facebook asking for a living kidney donor. Marien found eight willing donors, but Belgian physicians refused to perform the operation on the basis that it was unfair to award organs to individuals who were more "attractive" or skilled with social media, especially given that over one thousand individuals were already waiting on the Belgian transplant lists.

In the United States, there are no restrictions prohibiting individuals from using social media or other alternative methods to search for potential living donors. In 2012, Facebook adopted a feature that allowed users to add their organ donor status to their public profile and provided a link to donor registry sites. The introduction of the feature resulted in a significant increase in the number of people registered as organ donors, inspiring organ donor organizations to begin using social media to attract potential donors and to match donors and recipients. Critics of using this method argue that allowing public petitions for donors could lead to a situation in which individuals are tempted or engage in "organ trading" or "purchasing organs" from potential donors.

Bibliography

"About Organ Donation and Allocation." UCSD. Regents of the University of California, 2015. Web. 24 May 2015.

Duerr, Benjamin. "Should Patients Be Able to Find Organ Donors on Facebook?" Atlantic. Atlantic Monthly Group, 15 Apr. 2015. Web. 25 May 2015.

"History of Human Organ Transplant." Harvard Apparatus. Harvard Apparatus Regenerative Technology, 2014. Web. 24 May 2015.

Lamas, Daniela. "To Donate Your Kidney, Click Here." New Yorker. Condé Nast, 25 Sept. 2013. Web. 25 May 2015.

"Living Donation." Transplant Living. United Network for Organ Sharing, 2015. Web. 25 May 2015.

Lupkin, Sydney. "Organ Donation Rates: How the US Stacks Up." ABC News. ABC News, 18 June 2013. Web. 24 May 2015.

"Presumed Consent Not Answer to Solving Organ Shortage in US, Researchers Say." HopkinsMedicine. Johns Hopkins U, 29 Nov. 2011. Web. 29 May 2015.

"Organ Donation." Donate Life. Donate Life America, 2015. Web. 24 May 2015.

"The Need Is Real: Data." Organ Donor. US Dept. of Health and Human Services, 2015. Web. 25 May 2015.

What is sarcoidosis?

Causes and Symptoms

Sarcoidosis, an inflammatory disease of unknown cause, affects multiple organs and systems in the body. Most commonly affected are the lungs, lymph nodes, skin, and eyes. Other organs and systems that can be involved include the liver, spleen, bone, joints, heart, muscle, and central nervous system. Sarcoidosis is thought to be the result of an unusual immune reaction to an environmental antigen, such as a bacterium, fungus, or environmental toxin. Sarcoidosis is characterized by the presence of noncaseating granulomas in the affected tissues. These granulomas are ball-shaped clusters of immune cells consisting of macrophage and epitheloid cells encircled by lymphocytes. A granuloma begins when certain types of lymphocytes interact with antigen-presenting cells. Macrophages that have engulfed antigens are chronically stimulated by cytokines, differentiate into epitheliod cells, and fuse to form multinucleated giant cells. If a granuloma persists for an extended period of time, then fibroblasts and collagen encase the ball of cells. This eventually leads to
fibrosis, or permanent scarring, which can lead to organ impairment.

The incidence of sarcoidosis varies greatly by ethnic group, indicating a genetic component to sarcoidosis. In the United States, forty in one hundred thousand African Americans develop sarcoidosis, while five in one hundred thousand Caucasians develop it. In Sweden, the incidence is sixty-four in one hundred thousand. In general, more women develop sarcoidois than do men. Sarcoidosis can occur at any age, but the average age when it is detected is between twenty and forty years.

The initial symptoms of sarcoidosis may include coughs, wheezing, chest discomfort, night chills, and weight loss. Many patients learn that they have sarcoidosis when a routine chest X ray shows abnormalities. Most if not all of the symptoms of sarcoidosis are not unique to the disease, so diagnosis involves ruling out other conditions, such as an infection. Typical first signs of sarcoidosis include skin lesions, problems with the lungs (such as decreased lung function), and enlarged lymph nodes. A bronchoscopy may be performed to inspect the bronchial tubes and to obtain a tissue for biopsy. A positive biopsy would reveal a large number of white blood cells, general inflammation, and the presence of granulomas. Gallium-67 scans may be used, in which the radioactive element gallium-67 is injected and accumulates in areas of inflammation, infection, or rapid cell division. More recently, the more sensitive FDG-PET scan, which uses the radioactive sugar FDG instead of gallium, is being used for some patients. Patients with sarcoidosis in the eyes have redness in the eyes, photophobia, and blurred vision.

Treatment and Therapy

An estimated 60 to 70 percent of cases of sarcoidosis will resolve within one to two years. For severe sarcoidosis, corticosteroids, such as prednisone, are given to reduce inflammation. Since steroids can have severe side effects, treatment may not be given unless organs are impaired. Some 20 to 30 percent of patients will develop a chronic condition of persistent sarcoidosis that damages organs as a result of fibrosis. It is estimated that in 5 to 10 percent of patients, sarcoidosis will be the cause of death, usually from lung fibrosis resulting in respiratory failure or from cardiac or neurological complications.

Perspective and Prospects

The skin lesions of sarcoidosis were first recognized in 1869 by English dermatologist Jonathan Hutchinson. In 1897, Caesar Boeck independently described the skin lesions using the term “sarcoidosis,” meaning “fleshlike condition.” The multiple system involvement was recognized by Jörgen Schaumann in 1915, the same time that Alexander Bittorf described lung lesions of the condition. In 1941, Morten A. Kveim, a Norwegian physician, developed a test for sarcoidosis that involved injecting lymph node tissue from a confirmed sarcoidois patient into the skin of a person suspected of having sarcoidosis. If granulomas developed at the injection site four to six weeks later, then the test was positive for sarcoidosis. In 1954, Louis Siltzbach modified the test to inject tissue from the spleen of sarcoidosis patients. If the patient was receiving steroid treatment, then the granulomas might not develop, leading to a false negative on the test. The Kveim test is no longer used to diagnose sarcoidosis, largely because of the lack of commercially available Kveim reagent and its replacement by other
diagnostic methods, such as bronchoscopy. A promising new development in the treatment of extensive sarcoidosis is the use of FDG-PET to monitor a patient’s response to drug therapy. FDG-PET is more sensitive than the conventional gallium method. Research into the genetics of sarcoidosis indicates likely multiple genetic factors. A predisposition to developing sarcoidosis is associated with HLA-DQ and HLA-DR genes.

Bibliography:

Culver, Daniel A., Mary Jane Thomassen, and Mani S. Kavuru. “Pulmonary Sarcoidosis: New Genetic Clues and Ongoing Treatment Controversies.” Cleveland Clinic Journal of Medicine 71, no. 2 (2004): 88–106.

Iannuzzi, Michael C., Benjamin A. Rybicki, and Alvin S. Teirstein. “Medical Progress: Sarcoidosis.” New England Journal of Medicine 357, no. 21 (2007): 2153–65.

"Sarcoidosis." MedlinePlus, June 2, 2011.

Smith, C. Christopher, Jess Mandel, and Booker Bush. “Less Is More.” New England Journal of Medicine 344, no. 14 (2001): 1079–82.

"What Is Sarcoidosis?" National Heart, Lung, and Blood Institute, May 1, 2011.

Wood, Debra. "Sarcoidosis." Health Library, November 26, 2012.

What would be included in a thank you letter to Boo Radley if Jem, as an adult, were to write one in the future?

If Jem, as an adult, were to write Boo Radley a thank you letter, he would thank him for leaving the gifts in the tree, for mending his pants, and for saving his life on the night Bob Ewell attacked him. 

In chapter 4, Scout finds gum in the knothole of the Radley tree. A little while later, Scout and Jem find two "Indian-head" pennies: one dated 1906 and the other 1900. The kids consider these good omens and can't wait for what they'll find next. A few months later, and in chapter 7, they find the following:

". . . two small images carved in soap. One was the figure of a boy, the other wore a crude dress . . . Our biggest prize appeared four days later. It was a pocket watch that wouldn't run, on a chain with an aluminum knife" (59, 60).

After this big haul, Jem thinks about writing a thank you note, but Mr. Nathan Radley discovers what's happening and fills up the knothole with cement.

Between finding things in the tree, Jem finds himself in a predicament on the last night of summer vacation. In chapter 6, Jem, Dill and Scout go to the Radley house at night to get a glimpse of Boo through a window with a broken shutter. While escaping Nathan Radley's gunshots, Jem's pants get caught and torn in the fence. When he goes back for them, he finds the pants crudely mended and folded, waiting for him to come get them. This saves Jem from getting in trouble with Atticus, so he would thank Boo Radley for helping him that night as well. 

Finally, and probably most importantly, Jem would take the time to thank Boo Radley for saving his life on the night of the Halloween festival at the school. In chapter 28, as he and Scout are walking home that night, Bob Ewell jumps the kids with a large kitchen knife in hand. Jem's arm is broken in the scuffle, but it is Boo Radley who defends the children and carries Jem home. If Boo had not jumped in to help the children, they probably would have died.

If Jem, as an adult, wrote a thank you letter to Boo Radley, he would include all of the above events in his letter. He also would not call him "Boo." Out of respect, he would start his letter with "Dear Mr. Arthur Radley" and then mention all of the above items as listed.

In The Giver, why was Jonas chosen to be the next Receiver of Memory?

In Lois Lowry's immensely popular dystopian novel, The Giver, protagonist Jonas is chosen to be the community's next "Receiver of Memory." The Receiver of Memory held a vital role in this community, for, in order to sustain peace, the community had purged itself of memories, love, and colors. The Receiver is the only community member who remembers the time before this "Sameness;" it is his or her job to use the memories of the past to help the community make wise decisions in the future.

The reason the Elders chose Jonas for this great honor (and responsibility) is that he possesses the rare capacity "to see beyond." Examples of this ability include his sensitivity, his dreams, and his limited ability to see colors (for instance, he knew that an apple was red).