All stars start out using hydrogen as nuclear fuel. This hydrogen is fused together to form helium in a very explosive nuclear reaction that “powers” the star. As the hydrogen runs out, the star begins to collapse from a lack of radiative pressure from the core. The collapse of this much mass increases the temperature until the core is hot enough for Helium fusion. This process is repeated as the fuel continues to be consumed, from hydrogen to helium, helium to carbon, carbon to silicon, and silicon to iron. It is at this point that the already explosive reactions become even more cataclysmic. All of the previous fusion reactions release energy, but an iron fusion reaction actually requires energy. This process reverses the radiation pressure which causes a irreversible pull towards the center of mass. At its most compressed state, all electrons in the star are compressed into contact with the nucleus against the strong force. The resulting rebound causes one of the most powerful explosions in the universe a supernova.

Since Betelgeuse is near the end of its life as a super giant it is due to supernova in the next several years. When this happens, the resulting explosion will be approximately 10,000 times brighter than our sun, though it will be very distant. The supernova will last for several months, up to even a year. The brightness will block out every star in the night sky and will even be brighter than the moon. It will even be visible in the daytime. The extreme distance will limit any detrimental effects here on Earth (whether it be radiation or charged particles), preventing any poorly done future Hollywood movies. It won’t end the world, but having two suns in the sky will sure look cool.

See Also: http://stars.astro.illinois.edu/sow/betelgeuse.html

Surrogacy is a procedure in which sperm and egg fertilized in vitro are implanted into a female subject who has agreed to carry the pregnancy to term. She gives birth to the child and usually forfeits the child to the couple who has paid for the arrangement who then, for the most part, retain legal custody of the child.

For most surrogacy cases, the reason for pursuing this path usually is that the female of a heterosexual couple cannot carry her own child or the complication from her carrying term would most likely result in her expiration. This represents a little over 90% of all surrogacy cases. In these cases, for the most part, the legal proceedings have been clear: the male of the couple has provided the sperm and the female of the couple has provided the egg, and no one can challenge that the couple represents the legal characters of parents. For the most part, surrogate concerns have been sidelined as she has no legal connection to the child. Since the legal sphere has not as of yet gone to define what someone has to be involved in concerning the birth process to be considered a parent, surrogates usually find resistance and judicial scorn.

Another portion of the group paying for their children to be born of a surrogate are homosexual couples who provided the corresponding piece to the “child puzzle” from at least one partner. Here courts have been a little more uncertain and varied in decisions, but the rulings have still reflected the notion that sperm donor and egg donor, especially if the egg donor also carried the child to term, need to exist as legal guardians by current legal proceedings. If the egg was provided from another source, it becomes the choice of the women, individually, if they do or do not want to be involved in the child’s life.

The problem with the other 5% of cases not mentioned is that, quite frankly, it may turn babies into commodities. The Kehoes couple wanted to have a child but the female could not carry a child to term and it was very improbable that she could even conceive. The couple purchased their child from other people who had no known relation to them. They chose the route of surrogacy for the children they wanted much like someone picks between fine wines and strong spirits. The egg came from a medical school student at the University of Michigan and the sperm came from an athletic man who had maintained a 4.0 GPA throughout high school. They chose the surrogate mother based on a rating system that helped pick the “best” candidate for an easy delivery. Neither female nor male of the Kehoes couple had any part in the birth of the twins nor is there any genetic relation between the Kehoes and the children.

Legally, there truly is no answer for who are the parents of these children. The donors for the most part do not want to be involved and they usually view this procedure no more than people who donated blood for money. Legally, if those who provided genetic character to a child refuse to be legally responsible, the state needs to watch the children until foster parents adopt the children through the legal proceedings. The problem with the surrogate program is that while parents have to go through extensive screening for adoption, there is no standard for screening the parents who pay for surrogate procedures, and most couples are never screened aside from the question of whether or not their check clears. However, there is another problem: in these cases, the surrogate female is recognized, at least in some states, as an equal in legal rights to the children as the economically liable couple.

The surrogate female of the Kehoes case, Ms. Baker, challenged the couple in court for custody of the twins on the grounds that Ms. Kehoes was being treated for severe mental illness that would normally restrict her from adoption. Ms. Baker stated that had she known the mental state of Ms. Kehoes she would not have gone through with the surrogacy. The state of Michigan decided to rule with Ms. Baker and the children are now currently in her custody but the legal proceedings continue and the question of who will be considered legal guardians is still very much undecided. Similar cases have occurred in California, Oregon, New Jersey and Texas, all of which eventually ended in favor of the economically liable couple.

The question of whether or not any part needs to be played in the birth process as a requirement for parenthood still needs to be answered, as does the ethical implications behind “buying” your children. The miracles of fertilization now are to be met with the confines of law. What will occur from the encounter is still very much undecided.

For the original article please visit:
http://www.nytimes.com/2009/12/13/us/13surrogacy.html?_r=2&pagewanted=1

For the site that the Kehoes used to find their surrogate please visit:
http://surromomsonline.com/

For further references on foster care and the most up-to-date status of this and all cases please visit:
http://topics.nytimes.com/top/reference/timestopics/subjects/f/foster_care/index.html?inline=nyt-classifier

High amounts of fat in food, such as ice cream, not only affect a person’s stomach but also their brain. Some of the fat travels to the brain, which then causes the brain to send out signals to all of the cells in the body. These signals “tell” the cells to disregard the hormones leptin and insulin, which tell the body to “stop” eating to regulate body weight. When a human eats, these hormones send signals to the body to stop eating once the body is full, but these hormones do not always work when a human eats something enjoyable like “junk” food. Leptin is released to stop the feeling of hunger by fat tissue in the body and insulin slows the desire for food by increasing in the pancreas after detection of blood sugar from a meal.

In a study done at the University of Texas Southwestern Medical Center at Dallas, Dr. Deborah Clegg analyzed what kinds of fats affected the brain in this way. Dr. Clegg believes that the fat actually changed the chemical composition of the brain because the fat is incorporated into the brain. Dr. Clegg performed this study by looking at effects of different fats on the brain of animals after exposure by three different methods: injection directly into the brain, feeding the animal through a stomach tube, and infusion into the carotid artery a few times a day. Palmitic acid and oleic acid were the specific fats used. Palmitic acid is a saturated fatty acid and is found in foods such as butter and beef while oleic acid is an unsaturated fatty acid found in food such as olive oil. The results showed that palmitic acid affected the signaling pathways of the leptin and insulin over about three days while the oleic acid did not affect the hormones. These studies were done on animals but Dr. Clegg believes that the saturated fatty acids will affect a human’s brain in a similar way. In another study with rats, the saturated fats, especially palmitic acid, caused the insulin modulator to localize to the cell membranes in the hypothalamus, which slowed the insulin signaling in the brain. Dr. Clegg hopes to soon determine a way to reverse the effects of the palmitic acid on the brain signaling.

Many of the most successful drugs on the market today are being prescribed for ailments that are quite different from the ones they were originally designed to treat since many drugs have been found to bind to multiple targets. Sometimes these interactions lead to new uses for well established drugs. At other times, they may cause harmful side effects. Either way, knowing about these interactions allows for better use of drugs.

In the new method, drug receptors are not defined by structure or sequence but by the ligands that bind to them. This approach differs from structure-based approaches which usually use a receptor’s crystal structure as a starting point.

“This approach uncovered interactions between drugs and targets that we never could have predicted simply by looking at the chemical structures,” said senior study author Bryan Roth, M.D., Ph.D., professor of pharmacology and director of the National Institute of Mental Health Psychoactive Drug Screening Program at UNC. “We may now have a way to predict what side effects are likely to occur from treatment before we even put a drug into clinical testing.” internetchemistry.com

By using a modified version of an already established algorithm used to search gene-sequence databases, compounds were screened against a database of targets, asking how much the compounds looked like the ligands. The team compared 3,665 approved or investigational drugs with hundreds of targets which were defined by their ligands. The researchers predicted thousands of unanticipated interactions and experimentally tested 30 of them. Of these 30, they confirmed 23 of the interactions.

In one case, the team found  that Rescriptor, which inhibits the enzyme HIV reverse transcriptase, also inhibited the histamine H4 receptor. The scientists have linked Rescriptor binding to histamine H4 at physiologically relevant concentrations to some of the painful side effects that the drug has. In another example, the antidepressant Prozac, whose primary target is the serotonin transporter, bound the beta-1 adrenerfic receptor, a G-protein-coupled receptor (GPCR) that usually binds such compounds as epinephrine and norepinephrine.

Roth states that the power of their approach is that it can be used to uncover the real targets of pharmaceutical compounds quickly and efficiently, and will probably lead to a greater understanding of the many molecular targets of each drug. Consequently, this new method will be an important step forward for chemists to design drugs that act on multiple targets.

It’s great that publishers are making research publications more accessible, especially to those outside the traditional scientific community, but I don’t believe it will impact the day-to-day workflow of most researchers. I, for one, ‘grew up’ with photocopies of papers organized in folders and binders, graduated to printed copies of pdfs (in folders by topic/project), and currently maintain a large DEVONthink database of pdfs, text clipped from articles, notes, etc., as well as assorted paper notebooks. I find RSS access much more useful that a ‘Web 2.0‘ format.

Overall, the broader impact is likely with the publishers as they adopt similar formats to comply with the NIH Public Access Policy, although there are other implications. MIT’s Open-Access Policy is worth reading as is the policy for the University of California system.

Research on drosha and dicer proteins is already being applied to the medical field. According to a study in the New England Journal of Medicine, women who had ovarian tumors with high levels of the proteins Dicer and Drosha survived for an average of 11 years or more, while women who had lower levels survived only a median of around 3 years. Researchers hope that a better understanding of Dicer and Drosha might someday help guide treatment or lead to new types of therapy. These two proteins are essential in RNA interference. In the study, Anil K. Sood, M.D., University of Texas M.D. Anderson Cancer Center, in Houston, and his colleagues looked for Dicer and Drosha in the tissue from 111 women with advanced epithelial ovarian cancer. They found that 60 percent of the cancer tissues had low levels of Dicer, 51 percent had low levels of Drosha, and 39 percent had low levels of both. This study is the largest yet to link RNA interface with any cancer survival rates.

“In the past, people used to think that miRNA might actually promote tumor growth, but there is some emerging thought that some of the miRNAs might keep tumors from growing and actually function as a tumor suppressor,” says Sood, who is an associate professor of cancer biology.

Unfortunately this research does not have immediate application for women with ovarian cancer. However the finding may eventually help doctors to better determine if a patient needs more aggressive treatments.

This new research is causing many biotechnology companies to look at this lock-and-key mechanism as a potential way to fight other diseases. They are working to create new synthetic molecules called small interfering RNAs. These siRNAs are being tested as a way to treat eye disease and age-related macular degeneration.

J. Am. Chem. Soc., 2009. DOI: 10.1021/ja905596t

The study to test this hypothesis was conducted with male Wistar rats that were fed a chow diet (A/I) which was preferred to their regular Chow, and were also offered the choice of a chocolate-flavored chow. The rats were given the regular Chow for 5 days, and then were given the highly preferred sugary chow for 2 days. While they ate roughly the same amount of regular food each day, the rats over-ate the sugary chow, and then under-ate the less-preferable but equally acceptable chow (hypophagia). The group used A/I as well as the sugary chow, which had the same initial levels of energy intake and weight gain, to prove that the rats’ addiction was more than just nutritional. Given their similar caloric value, the rats still preferred and overate the chocolate diet more than the preferred A/I chow.

Ultimately, the group discovered that the rats going through chocolate withdrawal spent more time in corners of a maze, rather than the open parts, illustrating the previously mentioned anxiety effect. They found the anxiety to be attributed to corticotropin-releasing factor (CRF), which is involved in stress-response in the brain (commonly found in drug and alcohol withdrawal cases). This research marks the first time this factor was indicated in a type of food, or chocolate addiction. Could a CRF blocker be the answer to every chocoholic’s addiction? Cottone says yes.

What I found most remarkable about this study was the severity of chocolate or food addiction, and how it could be equated biologically to alcohol or drug addiction. This study suggests that on-and-off dieting could increase addiction and anxiety in withdrawal of that addiction.

PNAS, 2009. DOI: 10.1073/pnas.0908789106