Volume 7, Issue 3
April 2016
The Medical Journal of the Ramaz Upper School
Blood-Borne DNA Pinpoints Tissue Damage By: David Grinberg ‘19 Cells die all the time, and they shed fragments of their DNA into the blood. Now, many research teams are cultivating new ways to trace the DNA to its original tissue, hoping to detect early stages of a disease or monitor its progression. Noninvasive analysis of cell death is an exciting area with limitless applications. A technique for tracing the origin of circulating DNA detected the expected type of cell death in people with pancreatic cancer, type 1 diabetes, multiple sclerosis, and brain injuries. Since 2011, doctors have been able to order a test for Down Syndrome that inspects the DNA shed by a fetus into a pregnant woman’s blood. This test determines whether the child will be born with Down Syndrome as well as many other diseases. Another potential solution in inspecting DNA is to look at the Methyl chemical groups. Scientists have discovered that each cell type has a certain DNA methylation pattern. In October 2015, a group led by Dennis Lo of The Chinese University of Hong Kong stated in the Proceedings of the National Academy of Sciences (PNAS) that they could identify those methylation patterns in circulating DNA.
Benjamin Glaser from the Hadassah Medical Center in Jerusalem has given a cheaper and simpler approach. They say that by scanning circulating DNA for those hotspots in people recently diagnosed with type 1 diabetes, they can find dying β cells. β cells are insulin-producing cells in the pancreas. Those tested revealed proof of dying β cells in the blood of people who had been given islet cell transplants. Islet cells are tiny clusters of cells scattered throughout the pancreas. Pancreatic islets contain several types of cells, including beta cells, that produce the hormone insulin. Insulin helps cells throughout the body absorb glucose from the bloodstream and use it for energy. These scans show potential signs of immune rejection of the islets in transplant patients. However, Methylation is not the only way to trace circulating DNA. In the magazine Cell, a team at the University of Washington in Seattle have created a test that relies on tissue-specific differences in how DNA is packaged in structures called nucleosomes. The team could then use those nucleosome fingerprints to trace circulating DNA to the cancerous tissue.
Many researchers plan to test the nucleosome and methylation approaches in larger groups of people. Many scientists think that this research will not get us anywhere. Although, scientists also once had the same position regarding Down Syndrome being picked up from fetal DNA in a pregnant woman’s blood.
Staff Editors-in-Chief Arianne Rothschild Yakira Markovich Gabriel Klapholz Jessica Fuzailof
Faculty Advisor Ms. Lenore Brachot
Coffee Consensus By: Oriya Romano ‘17 More than 64% of Americans drink at least one cup of coffee a day. Coffee is a constant ‘pick me up’ that most are guilty of drinking in excess. Never during late nights and rough essays do we take a minute and think of the effects coffee may have on our bodies. Most are just glad to have the caffeine to keep them awake. Research and media are in constant debate over the issue of coffee being bad or good since there is no definitive answer. Coffee generally has a bad connotation due to it being called a vice. Additionally most parents refrain from allowing their children to drink coffee since it has a reputation for stunting growth. However science has yet to prove these accusations. There have been many meta-analyses proving that if coffee is drunk in moderation, which is about 2-6 cups a day, it can actually lead to benefits. For example, recent studies have shown that drinking coffee can lower the risks of Parkinson’s disease and other diseases that are related to the cognitive decline of the brain such as Alzheimer’s disease. It is important to keep in mind that these benefits come from drinking straight coffee, not decadent sweet drinks. Straight coffee has about 5 calories a cup but most sweet drinks can be well over 1,000 calories. At that point the coffee actually becomes harmful as it could lead to diabetes and other diseases. Doctors are most commonly concerned that if one is drinking coffee for the energy then they are actively tuning out the need of their body and ignoring sleep signals. “Coffee is an amazingly potent collection of biologically active compounds and needs to be respected as a potent drug” said Dr. Walter C. Willet of Harvard school of
public health. Dr. Willet touches upon an important point- caffeine is a drug. Many of its effects can make one addicted. This is bad because withdrawal can be hard and it will become difficult for the body to rely on its own natural source of energy. Dr. Rob Van Dam, an adjunct associate professor of nutrition and epidemiology at Harvard University said “Part of the energy boost comes from simply addressing the withdrawal symptoms coffee drinkers have created. If you never create that addiction then there is no reason to raise your caffeine level to sooth it.” Many people don’t drink coffee because it makes them overly jittery and causes stomach aches. This is because the acidity of coffee is associated with digestive discomfort, indigestion, and heart burn. Coffee is often drunk to relax and raise energy but actually if one drinks coffee in excess it could increase catecholamine (stress hormones). Again all these negatives effects of coffee are very rare and only occur if one drinks excessive amounts of coffee, however the general consensus seems clear: coffee is not unhealthy! It is important to keep in mind that what is meant by coffee is not the flamboyant drinks at Starbucks but simple coffee. “You should not feel as though you’re missing out on potential health benefits” said Dr. Donald Hensrud, director of the Mayo Clinic Healthy Living Program. The positive and possible negative effects of drinking coffee are so minor and rare that it is not something to worry about as long as it is under control. Nothing in excess is ever good for your body so if you enjoy coffee in moderation, it is absolutely fine to drink it daily. 2
A Blood Test to Detect Concussions By: Arianne Rothschild ‘16 Recently there has been accumulating evidence that concussions have more lasting effects then previously thought. Therefore, it is critical to monitor those with head injuries no matter how severe or minor they seem in order to minimize negative effects through proper treatment. CT scans of the brain are the typical way of diagnosing traumatic brain injury (TBI), though they cannot determine every case, nor determine the level of seriousness. Dr. Linda Papa, director of clinical research and an emergency physician at Orlando Regional Medical Center, has led a research team on developing a blood test to distinguish between the severities of head injuries. Papa and her team further studied two blood proteins known to be linked to brain injury and studied the changes of the proteins after a head trauma. For their study, the research team collected blood samples from 584 people, about half of which had brain related injuries, and the other half had other traumas (such as broken bones and chest injuries). All participants had their blood drawn 19 times, starting at within four hours to their injury and up to seven days later. Papa and her team tracked changes in the levels of the two proteins over this time, they were able to see how they changed and correlate it to people’s symptoms of their traumas. The levels of proteins GFAP and UCH-L1 rose within the first hour of injuries, no matter the type, and in all 548 people. GFAP, specific to cells that form a matrix for nerves in the central nervous system peak 20 hours after the injury, then decline steadily, though are still detectable a week later. UCH-L1 levels rise quickly immediately after the injury and peak at
eight hours most probably because they are released by brain nerves when stressed. Papa then compared the blood test findings to CT scans and saw that those who showed signs of TBI on CT scans also had significantly higher levels of GFAP and UGH-L1 than those with non brain related injuries. This suggests that the proteins can be relatively specific to TBI and not trauma in general. Due to these findings, Papa says, “I don’t think a blood will be the be-all and end-all but it would be a beautiful tool for us to have in the clinic to support a lot of our decision making.” For example, testing the levels of UGHL1 might be helpful for ambulance teams to assess the severity of a head injury since its levels peak in the hours just after the incident. It may also help determine when an athlete is able to return to playing after a concussion. This can also help reduce the amount of unnecessary CT scans administered; as only those with high levels of UGH-L1 are more likely to have TBI and can benefit from a scan. Since levels of GFAP remain higher for an extended period of time after a trauma, testing for those levels can benefit the injured who only see a doctor a few days after their injury. Higher levels of GFAP even after might indicate TBI and need for further testing. “We may not use these blood tests in a hundred percent of cases but probably in eighty percent of cases where there is a question mark, a blood test could definitely help,” Papa says.
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Study Reveals the Best Way to Quit Smoking By: Gabriel Klapholz ‘17 Quitting smoking is a very difficult task for those who are addicted to cigarettes. Many try to quit smoking through a gradual process of slowly cutting down on the number of cigarettes that they smoke daily. A recent trial, however, has shown that smokers would fair far better if they simply selected a day and quit for good. In 2014, nearly 17 out of every 100 U.S. adults ages 18 and older smoked cigarettes. Smoking presents a real threat to the overall health of U.S. society, as 40 million adult Americans smoke on a regular basis. Currently, smoking accounts for one in every five deaths in the U.S., making it “the leading cause of preventable disease and death” according to the Centers for Disease Control and Prevention (CDC). As a result, quitting smoking is of primary importance in this country and abroad. British researchers recently brought together 697 smokers for the aforementioned trial. At the time, these individuals smoked the equivalent of 15 cigarettes per day. The researchers asked the smokers to quit smoking within two weeks – half of the smokers were told to do so gradually, using nicotine patches and other forms of “nicotine replacement therapy” to slowly decrease the number of cigarettes that they smoked daily, while the other half simply quit abruptly at the end of the two weeks. One month later, 39.2 percent of those who had quit smoking gradually remained cigarette-free, while 49 percent of abrupt quitters did not recede back into their previous smoking habits. Six months later, 15.5 percent of the gradual quitters continued not to smoke compared to 22 percent of the abrupt quitters. The study was published in Annals of Internal Medicine.
Nicole Lindson-Hawley, a psychologist at the University of Oxford and the lead author of the study, said, “Our results should be particularly useful for those who want to quit and have no strong feelings about how they want to do it.” “For them, the best approach is abrupt quitting,” she explained. Nevertheless, Lindson-Hawley also mentioned that “40 percent were successful in the reduction group, and this is better than we would expect if people received no support at all.” The research could provide the next step in eliminating the prevalence of smoking worldwide. While the idea of abruptly stopping one’s daily routine of smoking may seem daunting, ultimately, as the study shows, the results are higher than those who draw out the process and quit smoking by gradual reduction of the number of cigarettes smoked daily.
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FDA Advises an Arsenic Limit in Infant Rice Cereal By: Matthew Hirschfeld ‘17 On Friday, April 1, the United States Food and Drug Administration announced a proposed limit on “inorganic” arsenic in infant rice cereal. The FDA explained that infant rice cereal is a leading source of arsenic exposure in babies because the element can be absorbed into the rice both by means of natural sources and by fertilizers and pesticides. The limit recommended by the FDA is 100 parts per billion, a level similar to that set by the European Commission for rice, which is used in the production of food for infants and young children. The agency noted that currently, most infant rice cereal sold in the United States either already meets or is close to the suggested limit. Susan Mayne, the director of the Food and Drug Administration’s Center of Food Safety and Applied Nutrition, explained, “Our actions are driven by our duty to protect the public health and our careful analysis of the data and the emerging science. The proposed limit is a prudent and achievable step to reduce exposure to arsenic among infants.” The FDA warns that exposure to inorganic arsenic in infants and pregnant women may lead to a child’s decreased performance on certain developmental tests that measure learning. The American Congress of Obstetricians and Gynecologists, ACOG, strongly approved the decision. In a statement, the association’s president, Dr. Mark DeFrancesco, expressed gratitude
toward the FDA “for its thoughtful analysis of arsenic in rice and rice products and its potential health impact.” He went on to ensure that “ACOG guidance will remain the same: Ob-gyns should continue to advise women to eat a variety of whole grains. For pregnant women, half of their gains should consist of whole grains.” The thirty-third element in terms of atomic number, Arsenic, As, occurs naturally in soil and water, yet it also is commonly found in and spread by fertilizers and pesticides. The FDA explained that there are two predominant types of arsenic, organic and inorganic. The inorganic form is more toxic. Rice, incidentally, has elevated levels of inorganic arsenic than other foods, and that is due to one main reason; as rice plants grow, they typically absorb arsenic from the environment more than other crops do. Rice cereal is used vastly for infants in the United States, and the FDA offers advice on the issue for parents and caregivers of infants. Parents and caregivers should feed babies ironfortified cereals, as it ensures the young ones are receiving enough of important nutrients. Iron-fortified cereals, however, are not the only option. Others that achieve this purpose include oat, barley, and multigrain. According to the FDA, pregnant women should eat a well-balanced diet which incorporates a wide variety of grains. It is estimated that exposure to inorganic arsenic in rice and rice products is responsible for an additional four cases of lung and bladder cancer 5
over a lifetime for every 100,000 people in the United States. While that is still four more cases than there might be otherwise, the FDA explains that that would be much less than a single percent of all lung and bladder cancer cases in the nation. The federal agency has observed that one can reduce inorganic arsenic levels in rice by between 40 and 60 percent by cooking rice in excess water, six to 10 parts of water to one part rice, and draining that water. Nevertheless, the FDA admits, this method may also remove some key nutrients from the food. The FDA has said that it will be accepting comments on the proposed arsenic limit for a 90-day period of time.
Digital Mammography can Help Predict Heart Disease By: Tyler Mandelbaum‘17 Heart disease is the cause of 22.4% of deaths among women in the United States, and breast cancer is responsible for 21.5% of deaths. The Centers for Disease Control and Prevention (CDC) report that these are two of the main causes of death among women in the US. The American Cancer Society recommends yearly mammography for women of ages 40-54 and those at high risk for breast cancer, and every 2 years for women aged 55 years and older. Digital mammography, which is used in 96% of mammography units in the US, can detect calcifications. This information could help to specify how much calcium is building up in the coronary arteries. Coronary arterial calcification (CAC) is an early sign of cardiovascular disease (CVD), and previous research has associated CAC with breast arterial calcification and atherosclerotic disease, heart attack, stroke and other cardiovascular conditions. New research
suggests that breast arterial calcification could be an equal or stronger indicator of future heart disease than high cholesterol, high blood pressure and diabetes. Dr. Harvey Hecht and his colleagues compared data from 292 women who had mammography and a non-contrast computed tomography (CT) scan. Results showed that 124 women (42.5% of the participants) showed signs of breast arterial calcification, and 70% of these women also had CAC, while 63% of those whose CT scan showed CAC also had breast arterial calcification. Half of the women under 60 had both CAC and breast arterial calcification. In younger women with breast arterial calcification, 83% had CAC. Results indicate that CAC is three times more likely in women with breast arterial calcification. Hecht urges clinicians to report the presence and amount of breast arterial calcification in women on a regular basis.
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Study Finds that Double Mastectomy Doesn’t Always Improve Chances of Survival By: Gabriel Klapholz ’17 The double mastectomy is becoming a common surgical option for women with breast cancer. The surgery includes the removal of both breasts even though the tumor may only be present in a single one. Many doctors, however, have found that the operation does not increase one’s chances of survival. A recent study, published online in the Journal of Clinical Oncology, claims that women who opt to have double mastectomies also do not improve their quality of life. The study was based on surveys distributed to thousands of women across the country. Vivien Foldes, who was found to have an early stage of breast cancer five years ago, underwent the double mastectomy operation. Now 58 years old and living in Woodmere, N.Y. as an accountant, Foldes doubts whether or not she should have gotten the surgery. Had Foldes known that the reconstruction process would last for five painstaking months and result in an inability to sleep on her stomach for the rest of her life, she may have reconsidered having a double mastectomy. Foldes sometimes asks herself, “Should I have done it?” Still, Foldes said that she wanted to have the surgery at the time because her mother had two different types of cancer, and Foldes “didn’t want to be waiting for the other shoe to drop.”
Dr. E. Shelley Hwang, the chief of breast surgery at Duke Cancer Institute and the leader of the recent study, stated, “Quite a few studies have shown that in patients who don’t have a genetic mutation that increases breast cancer risk, the benefit from removing the healthy breast — purely from a cancer perspective — is zero to tiny at best.” If longevity is no longer part of the discussion, then the question becomes: “Does it at least improve their quality of life?” Dr. Hwang wanted to answer this question by discovering if the double mastectomy had any additional benefits over the more simple procedure of removing only the cancerous breast. The results were very revealing. “I don’t want to sound terribly negative; some women had very good results and are happy they made the decision,” said Dr. Hwang, but “you’re not better off, you’re not happier.” Nevertheless, more and more women in the last few years have chosen to remove both breasts in a procedure called contralateral prophylactic mastectomy (C.P.M.). In 2011, approximately 11 percent of women who were having a mastectomy wanted a double mastectomy. In 1998, less than 2 percent chose the procedure. Breast cancer doctors expect the figures to increase further, despite the fact that women with early-stage breast cancer who have a
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double mastectomy have the same chances of survival as those who don’t opt for the operation. In fact, recent research has indicated that the healthy breast has a low risk of developing a tumor at all. Dr. Hwang claims that she has witnessed the negative effects of the double mastectomy. During reconstruction, there can be “surgical complications,” and many women have unrealistic expectations about how the reconstructed breasts will look. Ultimately, the surgery often results in complete loss of sensation in the breast area and can often lead to chronic pain as well. Dr. Hwang noted that “one patient said she couldn’t feel hugs anymore when she snuggled up to her kids.” The 3,977 volunteers participating in the program, 1,598 of whom had had a double mastectomy, filled out a detailed survey called BREAST-Q. The survey analyzed trends in physical, psychological, and sexual health, as well as breast satisfaction. Some questions on the survey dealt with whether or not women are comfortable with their own appearances, clothed or unclothed. In fact, the results showed that women who had had double mastectomies scored higher for psychological wellbeing and breast satisfaction.
Microbes in Our Bodies By: Sarah Araten ‘16 In the past, scientists have hypothesized that humans are made up of 1014 cells, but that 90% of those cells are not actually human cells. If most of the cells in our bodies are not actually human cells, then what are they? These mysterious cells are actually microbes, tiny microscopic organisms that are found everywhere in our world, including in and on our own bodies. Thomas Luckey, in 1972, said that humans have over 100 trillion microbes that are a part of our bodies. A few years later, in 1977, D. C. Savage agreed with Luckey and again claimed that there were 100 trillion bacterial cells that lived in and on our bodies. A later study said that there were 37.2 trillion human cells in the body. Scientists used this information to infer that there must be 372 trillion microbes living in the human body. This idea of us having “10 times as many microbial cells as human cells� has been an accepted one, despite the fact that there was no real evidence behind the idea. Now, a new study by scientists in Israel claims to have new evidence that shows that this idea of a ten to one ratio is in fact incorrect. These scientists looked at the large intestine, which houses the largest percent of bacteria in our bodies. They estimated that based on the size of the large intestine and
the size of the bacteria that would live there, there are 39 trillion microbes living in our large intestine. The Israeli scientists then looked at other places that are homes to bacteria that live in our bodies, in places such as the small intestine, mouth, skin, and stomach. They saw that the number of bacteria living in these places was so small in comparison to those living in the large intestine, and agreed that these bacteria would have no big effect on the overall number of bacteria in our body. They therefore concluded that humans only have around 39 trillion bacterial cells in our bodies, which is a much smaller number than the previous estimate that humans had 372 trillion bacteria in their bodies. This new study shows that the ten to one bacterial cells to human cells ratio is outdated. This research was important because it is always beneficial to have the most accurate idea of how our bodies work and how other organisms are using our bodies. As of now, scientists are looking to use this new information in ways that will be able to help us in the future. For more information on microbes, their discovery, and the history of the scientists who studied them, check out the book Microbe Hunters by Paul de Kruif.
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A Gene May Account for the Higher Rates of Some Cancers in Black People By: Matthew Hirschfeld ‘17 A new study, published in the journal, Genes and Development, suggests that a single gene variant might be responsible for the shorter survival times and higher death rates of black Americans with common cancers than those of other races. While researchers in the past have analyzed potential socioeconomic explanations for this phenomenon, others have devoted their efforts to the genetics behind, if there were any. The senior author of the potentially impactful study is Maureen Murphy, professor and program leader in the Molecular and Cellular Oncogenesis program at the Wistar Institute in Philadelphia. Professor Murphy announced, “We may finally have a truly genetic explanation for why African-Americans are more prone to a variety of cancers.” She further elucidated in an institute news release, “This is a variant that has never been observed in Caucasian populations, so identifying people who have this variant may be crucial for providing improved prognosis and personalized treatment that will lead to better outcomes.” The study’s researchers focused in excruciating detail on a specific variant in a tumor suppressor gene that is mutated and activated in most cancers. The variant occurs only in individuals of African descent. Its presence among black
Americans is approximately 2% and among all Africans is about 8%, according to the study’s authors. In order to analyze the effects of this particular variant, the researchers constructed a mousemodel. In their study of the mice, 80% of those with the variant developed cancer. The most common forms of cancer that the mice with the variant experienced were liver cancer, colon cancer, and lymphoma. That said, it is important to recognize that findings in mice do not always translate to humans. Nevertheless, the conductors of the study report that liver cancer, in particular, is more common in black Americans than in other racial/ethnic groups. They similarly note that colon cancer accounts for approximately 9% of all newly diagnosed cancer cases among black Americans. Professor Murphy acknowledged that the study’s findings need to be validated in humans. The researchers explain that in order to accomplish such, it would be necessary to assemble a large population of people to accurately examine this gene variant’s effects. “However, we now have some of the strongest evidence ever obtained for a genetic basis for this disparity and a larger, population-based study is warranted,” concluded Professor Murphy.
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Is One’s Love or Hatred of Physical Exertion Decided in the Womb? By: Matthew Hirschfeld ‘17 Do you enjoy going to the gym? Do you feel naturally pulled there? Or do you feel the call to exercise is one that is better off being sent to voicemail? According to a scientific study recently published in the FASEB Journal, there is empirical evidence tending to show that our experience in the womb influences how physically active we may grow up to be. In the study, pregnant mice that physically exerted themselves gave birth to mice that were more physically active in their lives than the offspring of parent mice, who did not exercise. Discovering methods of motivating individuals to be physically active has become all the more so critical in light of the serious obesity epidemic taking place in the United States, as well as across the globe. At this time, more than 33% of American adults are obese, and more than one in every six children or young adults aged between 2 and 19 is obese, putting him or her at risk of type 2 diabetes, heart disease, stroke, and several forms of cancer. The study’s director, Professor Robert A. Waterland of Baylor and Texas Children’s Hospital, explains that the observational studies of this issue that have been conducted in the past could not claim with certainty that their results were caused by the mother’s gestational behavior. While previous studies have observed that pregnant women who are physically active have children who are more likely to be physically active, these results, as Professor Waterland points out, could be due to factors other than the fetus’s experience in the womb, for example a mother’s post-birth influence or possibly even a genetic predisposition that’s passed from mother to child. Professor Waterland remarked, “Our study in a mouse model is important because we can take all
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those effects out of the equation.” The researcher’s procedure for the study involved taking female mice that naturally enjoyed running and dividing the mothers-to-be into two distinct groups. Running wheels were available to one group before and during pregnancy, while the other group had no access whatsoever to such exercise equipment. The mice with running wheels ran10 km per night, and as their pregnancies progressed, they ran less and less, walking about 3 km per night in third trimester. The results clearly showed that the mice born to mothers that were physically active during pregnancy were 50% more physically active than the mice born to mothers that did not physically exert themselves during pregnancy. Furthermore, this tendency was not short-term. The higher proclivity to exercise of the mice born to mothers that did so during pregnancy lasted into their adulthood. In evaluating the results Professor Waterland stated, “I think our results offer a very positive message. If expectant mothers know that exercise is not only good for them but also may offer lifelong benefits for their babies, I think they will be more motivated to get moving.” With respect to our current conception of nature vs. nurture, Professor Waterland explained, “Although most people assume that an individual’s tendency to be physically active is determined by genetics, our results clearly show that the environment can play an important role during fetal development.” The researchers concluded, “Our findings show for the first time that maternal physical activity during pregnancy affects the offspring's lifelong propensity for physical activity and may have important implications for combating the worldwide epidemic of physical inactivity and obesity.”
Works Cited Blood-Borne DNA Pinpoints Tissue Damage Tests of Blood-Borne DNA Pinpoint Tissue Damage – sciencemag.org Coffee Consensus http://nyti.ms/1cHE2wM A Blood Test to Detect Concussions http://time.com/4272765/blood-test-for-concussions/ Study Reveals the Best Way to Quit Smoking http://well.blogs.nytimes.com/2016/03/17/quitting-smoking-cold-turkey-may-be-your-bestbet/?ref=health http://www.cdc.gov/tobacco/data_statistics/fact_sheets/adult_data/cig_smoking/ FDA Advises an Arsenic Limit in Infant Rice Cereal http://www.webmd.com/children/news/20160401/fda-suggests-limit-for-arsenic-in-infant-ricecereal?page=2 Digital Mammography Can Help Predict Heart Disease http://www.medicalnewstoday.com/articles/308309.php Study Finds that Double Mastectomy Doesn’t Always Improve Chances of Survival http://well.blogs.nytimes.com/2016/03/21/no-regrets-after-double-mastectomy-but-questionsremain/?ref=health Microbes in Our Bodies http://www.nytimes.com/2016/02/16/science/40-trillion-bacteria-on-and-in-us-fewer-than-wethought.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollectio n=science&region=stream&module=stream_unit&version=latest&contentPlacement=2&pgtyp e=sectionfront http://commtechlab.msu.edu/sites/dlc-me/zoo/ziwim.html Gene May Account for the Higher Rates of Some Cancers in Black People https://www.nlm.nih.gov/medlineplus/news/fullstory_158079.html Is One’s Love or Hatred of Physical Exertion Decided in the Womb? http://www.medicalnewstoday.com/articles/308575.php
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