Students from Writing in Biology polishing their blogging skills.
Wednesday, February 25, 2009
Cure for HIV...Stem Cells?
After recieving a bone marrow transplant, a 42 year old man from Germany who had leukemia and was also infected with the AIDS virus, seems to be cured of both leukemia and the HIV virus. The bone marrow donor, was apparently naturally resistant to the HIV virus. This resistance is the result of a mutation (deletion of a segment) in the CCR5 receptor encoding gene. These receptors are found in CD4+ T cells and are used by the HIV virus to enter the cells. It is reported that 1% of the European population carries this mutation.
Twenty months after the patient stopped taking the AIDS drugs he was on, doctors could not find evidence of HIV in the blood of the patient. Although this has been the first reported incident, doctors say that further testing using bone marrow transplant to treat AIDS will not be done. Bone marrow transplants involve killing off all of a patient's blood forming stem cells before replacing them with the donor's. This process is extremely painful and there is a high risk of death until the new stem cells restore the patient's immune system. Although no further testing on bone marrow transplants on patients without leukemia will be done, the same process will be repeated for other leukemia patients who also have AIDS.
Drugs intended to block the CCR5 receptors have been made, although they do not prevent the virus from completely binding to the CCR5 receptors. It may do this by outcompeting the inhibitor, or finding another section of the receptor to bind to.
-Julio Rodriguez (group c)
Update: They are currently doing research on this topic, trying to find how to genetically modify these sepcific cell types with this mutation. The problem is that the HIV virus has evolved in such a way that not all strands enter cells through this process. Although they are currently working on this, I have not heard of any results or if they are even testing on human subjects yet.
Is it hard to comprehend that one race is more linked to cancer over another, especially in the same country. While racial disparity in cancer death rates is decreasing, African Americans still have a greater chance of cancer than whites. Although since 1991, cancer rates among African Americans has been steadily decreasing, their rates are still nocticably higher than whites. In 2005, when compared to white men and women, cancer death rates in African-American men were 33% higher and 16% higher in African-American women.
Prostate, breast, lung, and colorectal are the most common cancers among African Americans. African Americans are most likely to be diagnosed in advanced stages of the disease for all cancer types. This is also what contributes to death rates being higher in this race. As we know, advanced stages of cancer are less treatable.
The reason for this discrepancy is not clear at all. Some reasoning points to most of the African American population has "far less utilization of screening", "barriers to high-quality health care," and being overweight or obese. " And according to the National Health and Nutrition Examination Survey, 76% of African Americans are overweight and 46% are obese, compared to 66% and 33%, respectively, of whites."
extra insight: “Rates are driven by social and economic factors,” says Jemal. "Many African Americans live in poor, urban areas where there are limited recreational opportunities, and they're less likely to find healthy foods like fruits and vegetables. There are a lot of environmental deterrents for persons residing in poor neighborhoods, from cancer prevention to early detection and treatment,” Jemal says
Kissing is one of the most common ways to express affection. However kissing may actually have a biologically positive affect on the people participating. Over 90% of human societies express affection by kissing. Many other animals express affection with facial contact. Some animals, like the chimpanzee even kiss just like humans. This tendency lead many scientist to believe that kissing probably offers some type of evolutionary advantage.
Wendy Hill of Lafayette College put this belief to the test. Fifteen couples were brought in to carry out an experiment. First, saliva samples were taken to measure the levels of the stress hormone Cortisol, and blood samples were taken to measure the level of Oxytocin, which is a hormone associated with bonding. Before the experiment women naturally had higher levels of Oxytocin then men, and women who took birth control had higher levels than women who didn’t. Couples were then told to kiss, hold hands and talk for fifteen minutes. After each test saliva and blood samples were taken.
The results of the experiment was unexpected. After the kissing portion of the experiment, men’s level of Oxytocin increased like expected. However, women’s levels of Oxytocin dropped. The hand holding portion of the experiment yielded similar results, but to a lesser extent. Both genders stress level dropped in kissing and holding hands, more so in kissing. An interesting tendency reported was that couples who had been together longer showed a greater increases in both holding hands and kissing. So if your stressed out, find someone to kiss.
Child abuse may have longer-lasting effects on the brain than previously thought. A new study looked at men who had been abused as children. In this study, scientists were able to locate a gene involved in stress control that seems to be affected, even years after the abuse, which seems to follow the same pattern as a similar gene linked to stress levels in abused rats.
Child abuse here is defined as maternal neglect. In the past, studies on maternally neglected rats revealed that more stressed baby rats are unable to turn off the hormone that is released in response to stress, therefore, they are unable to calm themselves down. The hypothalmic-pituitary-gland (HPA) axis, is a part of your endocrine system that is responsible for secreting hormones in response to stress. The glucocorticoid receptor is responsible for slowing down the HPA response and lowering the stress levels. Scientists have claimed in previous studies that matneral negelect alters the regularotry region of the gene responsible for the glucocorticoid receptor, making it malfunction and not do it's job - not lowering the hormones put out by the HPA.
Scientists have now idtentified a very simular type of situation in humans. In Montreal, Canada, at the University of McGill, Neuroscientist Michael Meany and his colleagues compared the brains of dead men who had been abused and killed themselves to non-abused men who had killed themselves and non-abused men who had died from natural causes. These scientist found the same pattern of non-expression of the gene responsible for the glucocorticoid receptor in abused rats and in the abused men. This change was not seen in the other two groups, which further supports the idea of abuse causing a change in genetic expression.
This study helps in finding out the causes of health problems in adulthood of those who have been abused. The Neurologist Michael Meany was quoted in saying that in the past decade there has been accumulating evidence "that abused indivudals are less healthy in adulthood." Apparently, besides emotion problems, people who have been abused suffer from "obesity, heart disease and autoimmune disorders". This study certinaly helps find out why.
Have you ever been walking by the campus pond during mating season for the ducks? If you have, you will know what I am talking about when I say that the female ducks get raped by the male ducks. This is actually scientifically true; the male ducks rape the female ducks. Well, if you weren't surprised by that, you will be by this: It has been shown that female ducks' vaginas have evolved so that are unwelcome to males' penises!
Male ducks are pretty aggressive when it comes to getting their sperm into females, and the females are helpless when a group of males "gang" up on her. It is easy for the male to rape the female and pass the sperm into her. Not anymore, Mister Duck! The females come out on top again (no pun intended). Female vaginas have evolved to be spiral and others had cul-de-sacs along the route. This would essentially be impossible to pass sperm into if raping, but with consent, the sperm would have a one way ticket.
Scientist Tim Birkhead has been studying this for some time and he says that this type of evolution in the females is only shown in species where there is forced sex apparent. Otherwise, any other bird species has a simple route, with no obstacles. He also says that, with this evolution, you can expect the males to (over time) evolve more elaborate and longer phalluses. With that, it would just be a cycle of evolving genetalia over time.
So to all of those guys out there who joke around saying guys are better than girls, think again! Though this is an unconcious phenomena, and it took a long time, the female duck has what it takes to win the race. With all of those obstacles to overcome, the males have to do a little bit of work to gain his rights to a female!
Sure the Anaconda is currently the worlds largest living snake, but what about it's ancestors? Well, researchers made a huge discovery when they were digging in Cerrejon Columbia, the largest snake in the history of the world.
Jason Head of the University of Toronto and colleagues discovered 28 fossilized snake vertebrae and ribs in an open-pit coal mine at Cerrejón. The vertebrae's structure suggests the snake is closely related to the boa constrictor, leading the team to name the species Titanoboa cerrejonensis, or 'titanic boa from Cerrejon'. By comparing the shapes and sizes of the two best-preserved vertebrae to those of living snakes, the researchers calculated that the snake was 12.8 meters long and weighed 1,135 kilograms(Anaconda vertebrae left, Titanoboa vertebrae right) . Also interesting is the researchers can use the size of the animal to determine more about the climate and environment when this creature existed. They can determine what median temperature would support such a creature of that size and the theoretical amount of energy/resources to keep that creature alive.
Discovering monstrous fossils is always a fascinating occurrence. They reveal a time before we can imagine, where things were built much bigger and much stronger. However, despite these powerful attributes, the fossils also help support the belief in natural selection and survival of the fittest; extinct animals show us failed fitness. This titanic boa is just one of hundreds of examples where natural selection took place, forcing species' ancestors to adapt or become fossils themselves.
Everyone in this class has taken Biology 101 and 102. In those courses we learned a lot (admittedly, some more than others), but one main thing that we could all take away from them is a basic understanding of animal cell structure and function. Or so we thought! Graham Warren, Ph.D. and Professor of Cell Biology at Yale Medical School has made an interesting find involving our old friend, the Golgi apparatus. Many scientists agreed that the Golgi apparatus is little more than an extension of the endoplasmic reticulum, an organelle responsible for, amongst other things, fixating ribosomes during protein synthesis. The Golgi apparatus itself was viewed as multiple membranous layers through which proteins secreted from the endoplasmic reticulum pass through on their path to target cells or to other parts of the cell. Warren's multinational research team discovered an extracellular matrix that could regulate the growth and division of this alleged organelle, a system of proteins that is not observable through regular electron microscopy. Warren and his team focused on these proteins that form a sort of "scaffolding" for the membranes. The implications of this kind of research are far-reaching and may be of particular interest to those conducting research in cancer. The most significant problem in cancer is that the cells continue to divide inexplicably. If the Golgi apparatus is a separate organelle, then this would mean that the structure responsible for a large part of protein, hormone, and growth factor transmission within and between cells is actually growing and dividing independently, and is separately inherited from other cell organelles like the endoplasmic reticulum. Warren said that he would continue looking at the Golgi apparatus, "from a basic cell biology perspective that has medical implications for diseases like cancer". (http://www.biology-online.org/articles/yale-scientists-give-golgi-apparatus.html) and (http://www.cellbiology.yale.edu/faculty/warren_g/warren_g.html) While Warren's team isn't making any promises, I would like to think that redefining and perfecting our understanding of basic cellular processes can allow us to remain optimistic on developing a cure for cancer within our generation.
With so many infections and viruses out there, parents are starting to worry about their children in schools, whether they are elementary school kids or college students in dorms. After reading an article about methicillin-resistant Staphylococcus aureus (MSRA), these people can put their fears to rest about a killer outbreak and their kids getting sick. MSRA is largely confined to hospital settings and not so much in community based settings. A 10 year study shows that the rate of these infections are decreasing within the common public.
MSRA is an antibiotic resistant strain of bacteria. It's no wonder we have so many higher occurrences of infections that deal with MSRA because antibiotics are being prescribed so often. Even if a doctor prescribes the right medication for the right infection, people often abuse the medication or don't take the full prescribed course. Working in a pharmacy I try to make it clear to customers getting azithromycin that they have to take the full amount in the right period of time. These days bacteria are mutating and resisting the medications. I also hate when doctors are prescribing for something that is viral because antibiotics do not work on those so it just gives the bacteria a chance to get used to the antibiotics.
From 1997-2007 the study showed that the infections among the ICU patients and has dropped 50%. Although it has decreased with ICU patients, the overall rate within the hospital has increased by 26%. Nearly 64% of staph infections of ICU patients can be traced to MSRA. So if a patient has a catheter and gets a bacterial infection, it will most likely involve MSRA. To keep the infections at bay the hospitals have come up with better techniques for inserting catheters and they have also cut down the leave-in time for catheters. The ICU patients need the most care when it comes to germs and I am glad to hear overall the rate of infections are decreasing.
-Katie Cyr (week 2)
Update:
Some more good news, severe MSRAis not common. It typically hits people with weak immune symptoms that visit the hospital setting often. You are more likely to catch other bugs more easily rather than MSRA. Like I said, most ICU patients get it because they are usually recovering from serious bodily trauma. There are more ways MSRA can enter their body because of all the tubes. This bacteria lives in your nose most of the time so it's unusual that you get seriously infected out of the blue. It needs to be transferred into an open wound to cause more damage.
I think the only thing that the hospitals can do is to keep up with regular hygiene. No matter what you do, you will get infected with something. We don't live in plastic bubbles and I don't think people will want to. Just remember, keep washing your hands, cover your wounds, don't share personal items like towels or razors, avoid hot tubs if you have an open sore, etc. Most of this stuff is common sense though so if you take care of yourself your chances of getting this is slim to none. So go enjoy yourself and don't worry about all the inevitable harmless bugs out there.
Big cat conservation groups and the Mount Sinai Medical center are teaming up to change human perception of big cat species--and save human lives.
A new program, developed by the New York based conservation group Panthera in collaboration with the Mount Sinai Medical Center, will train “doctor conservationists” in the human-health benefits of saving wild predators. In Central and South America where jaguars are known as cattle killers, the species is not only at risk of being hunted, but also of declining genetic health as their habitats shrink and populations are cut off from each other. A decline in top-level predators can lead to a boom in prey populations. Scientists have found a direct correlation in this cascade effect and an increase in zoonotic diseases, or diseases spread animal to human. HIV, West Nile virus, and avian flu are examples of zoonotic diseases that have existed in the environment but have been kept in check until relatively recently.
The goal of the program is to integrate the concept of conservation and its human-health benefits into medical training. The students will then have opportunities to practice in parts of the world where humans and wildlife live in close contact. The doctor-conservationists will also work to educate the local communities on the importance of tolerating jaguars and other predators. Another goal of the program is to boost efforts to establish “genetic corridors”, or paths of protected habitats that cross human-populated areas and connect wildlife preserves. Panthera’s Jaguar Corridor Initiative would potentially link about 90 distinct jaguar populations in Central and South America, and the Tiger Corridor Initiave would attempt to do the same in Southeast Asia. Panthera and other conservation groups stress the importance of maintaining genetic diversity in predator species.
Posted by Jane de Verges (week 2)
Update In response to several comments, I found some background information about zoonotic diseases.
Zoonotic diseases are passed from animals, wild or domestic, to humans. Diseases passed from humans to animals are called reverse zoonotic. In early human history, zoonotic diseases posed little threat because early humans lived in mostly isolated groups. Because of this, epidemic diseases often burnt out after the first generation of illness because the population affected would develop an immune response. The diseases we may think of as epidemic are actually zoonotic diseases (like the plague!). There is also good evidence that influenza, measles, smallpox, and diptheria originated in other species. Another interesting note: for many "human" diseases, the human is actually an accidental victim as well as a dead end host (this is the case for rabies, anthrax, and west nile virus.) Malaria and Elephantiasis are technically not considered zoontic, because although they are transmitted by insects, the human host is part of the disease's life cycle.
A note on HIV: HIV is believed to have evolved from the closely related Simian Immunodeficiency Virus (SIV), and transferred from chimps to humans in the early 20th century. Scientists disagree on exactly where and how this occurred.
Another piece of related information I found interesting: In 2000, researchers discovered that there are no subspecies of jaguar. From Southwestern U.S. to Argentina, all jaguars are the same. There is no other large carnivore like this. Jaguars require a very unique conservation model. Click here for a map of the Mesoamerica Jaguar Corridor project, from Panthera.org.
The banana is America's number one fruit, in fact the average American eats approximately 25 pounds of bananas per year, more than any other fresh fruit. But that is all likely to change very soon; the banana as we know it is headed towards extinction. The culprit is a soil fungus that causes Panama disease (Fusarium wilt) which slowly kills the plant by blocking its xylems. Without these water transporting pathways it is only a matter of time until the plant wilts and dies.
The bananas we eat today represent only a fraction of the thousands of banana species that have grown around the world. Bananas were first cultivated in southeast Asia, but different varieties were brought to Africa and then South America. In the process many species were lost as only a few varieties were cultivated commercially. By the 1900s the choice banana of the Americas was "El Gros Michel." However in the 1960s, Panama disease began to wreak havoc on Big Mike; it was a banana apocalypse. Luckily a replacement was found in the smaller but nonetheless delicious Cavendish, which was resistant to the fungus. Since cultivated bananas do not reproduce sexually on their own and plants can yield fruits for many years, the genetic makeup of the Cavendish is virtually identical across the globe. The Cavendish runs the banana world, but trouble has been brewing in the banana community.
Recently, a new strain of Panama disease called Tropical Race 4 (TR4) has began to kill off the once heroic Cavendish. It is slowly spreading around the world through contaminated plants and shipping containers. It is no longer a matter of if... but when. The fact that cultivated bananas do not reproduce sexually and that the Cavendish is almost 100% seedless makes it very difficult to crossbreed plants. This limited genetic variation will prove to be the ultimate downfall of the Cavendish as the only known defense against Panama disease is genetic resistance.
There will be a hole in the hearts of many Americans when the banana is no more, but the real problem is that Panama disease affects many species of African bananas. These bananas, which function more like potatoes, are the staple food of many of the people living in the area around Lake Victoria. The effect of the eminent banana pandemic will be extremely profound. For this reason scientists are vigorously searching for genetically resistant bananas. Laboratories around the world have been combining rare and feral banana species but no delicious, high-yielding and most importantly resistant species has been created yet.
I first heard about this when I was reading this National Geographic article a couple of months ago.
Barker, C. L. Conservation: Peeling away. National Geographic Magazine, November 2008.
Calin Darabus (2)
UPDATE:
No one is really sure when the Cavendishes will disappear but most people estimate that they will be gone within the next ten years. Malaysia was once a large grower of bananas but within five years of TR4 hitting all the plantations were destroyed. There are greenhouses and laboratories around the world that have isolated varieties of bananas growing (there are over 1000 varieties), so the bananas will never really become extinct but they will never be able to grown commercially. The good news is that the banana genome has been entirely mapped, so scientists have the tools they need to engineer some resistant bananas. Hopefully they will find some results soon. I hope that all of you keep up with this, because its really very interesting and I know bananas have a spot in all our hearts.
The Maculinea rebeli caterpillar may seem harmless, but it has the ambition to become Queen of the ants. You might ask me, how can a catepillar become a Queen? Usually when you think about catepillars would you think that they have the slightest bit of intelligence? Do not underestimate these organisms you might be surprised.
Jeremy Thomas of the University of Oxford in the United Kingdom believe that chirping play a great role in the ant community. Ants chirp by scraping one of their appendages against the ridges on their posterior. Worker ant chirping are at a lower frequency than queen ant. It is by this particular chirping that lets the worker ants know where their Queen rests. Worker ants become more attentive when the Queen chirps, sort of like ringing a bell for the butler.
Caterpillars may enter an ant colony when having the scent of an ant. Even after accomplishing such a feat it will not be recognized as royalty. By evolution the Maculinea rebeli caterpillar has learned to mimic ants' smell and the sound of the Queen. Knowing how to chirp like a Queen brings the service of the worker ants. As a fake Queen the caterpillar gains free food and safety from predators. Being able to live a blissful life as a pampered Queen.
As a long time resident of Western Ma, I am no stranger to finding ticks on me or my dogs.Finding a tick or two never really bothered me until a little over a year ago when I contracted Lymes disease on a camping trip with friends.
Lymes disease is actually a combination of a number of spirochete bacterium that enters the body upon being bitten by a tick, the most common bacterium being Borrelia burgdoferi.Also in the spirochete bacterium family, is the STD syphilis.Lymes disease is contracted after an infected tick is left attached to an unaffected host for at least 24 hours before being removed.
Lymes disease is responsible for 90% of vector-borne illness in the United States and had been reported in 49 of the 50 states, (Oregon being the lone state) and is present on almost all the continents.So basically put, regardless of your outdoor activities, this is definitely a disease that can, and will find you.
Symptoms of lymes disease vary with infection.Depending on the time infected and the bacterium contracted, symptoms can include, but aren’t limited to: headaches, stiffness, fever, severe muscle pains, weakness to paralysis of limbs, difficulty speaking and chewing, stroke, seizure, sleep disorder, severe cognitive and emotional changes, blindness, nausea, diarrhea, anorexia, difficulty breathing, miscarriage, and has even been attributed to cause of suicide.
For me, at first I felt like I was permanently hung-over.My neck was sore, I was overly tired, I couldn’t sleep, and I couldn’t eat.I spent the majority of my nights half asleep in the bathroom vomiting.During this time I began to notice a bruise on my inner leg that was slowly increasing in size.At first it was a small purple bruise but after a few days it was accompanied by large red rings around it.By this point I had stopped eating almost entirely and had given up on any strenuous activity. After about 3 weeks of this my inner leg had become almost entirely engulfed by the bull’s-eye shaped rash and it had gotten to the point where my parents started becoming concerned.
I self-diagnosed myself and went to my doctor where upon seeing my rash and hearing my symptoms promptly referred me to a local Lymes specialist.Because of my advanced symptoms and tell tale rash mark I was instantly put on antibiotics and given a number of blood tests.
Upon return of my blood tests I found that I had been infected by three different strains of the bacteria, including an especially viscous one which was the partial cause for the intense and acute symptoms that normally take years to appear in those infected.Another reason for my quick reaction to the disease was the fact that my body’s cells are actually host to markers that are extremely similar to those of Lymes, causing my body to literally kill itself.
It took about 4 weeks of anti-biotic treatment before I was close to 100% again; however I still am recovering from a staggering 30 pound loss from the 2 months of infection. Although I was greatly inconvenienced by it, I consider myself lucky. The bulls eye bruise that led me to assume I had Lymes only occurs in 9% of Lymes infections. In most cases people will stay infected for years with only minor symptoms leaving the bacteria time to spread across the body and become extremely difficult to treat.
Sources:
http://www.lyme.org/
Nick Cline week 2 (B)
UPDATE -
As far as symptoms go, the more damaging ones like mental deterioration and blindness tend to appear way later in infection. This is because the virus virtually spreads over your entire body and as it does it leaves a trail of symptoms.
I knew about my multiple infections because I got a blood test checking to see if I actually had the disease or not. Strangely it also showed that at one point I had also contracted mono. I've actually been tested for mono previous to that and it had never showed up positive, though there was one occasion where i was 99% sure i had it.( the school did the original mono test that proved negative, so needless to say i don't trust UHS anymore).
Yes ticks are the only organism that can spread lymes. The way they go about it differs from specie to specie. Ticks go through multiple life stages which are prompted by blood meals. For some species a tick can contract lymes in an early stage and will keep it for subsequent stages, however, other species will lose their ability to pass the disease in between morphs. Not all ticks carry the disease either, the increasing prevalence of the disease is mostly caused by an increase in the ammount of large animals like deer and bears that are in proximity to humans. Also previously large ammounts of DEET used to kill off ticks and large animals who were poisened but now there is no anti-tick chemicals being used that are anywhere near effective as DEET.
Dung Beetles forgo feces for a diet of live millipedes.
The Deltochilum valgum also known asthedung beetle, hasturned from scavenger to killer and is now preying on millipedes instead of the dung from other animals. This is a rare change in diet is an example of evolution for the dung beetle. The dung beetle usually feeds on other animals dung to get the bacteria from their excrement. But instead of following the trend of all other dung beetles the Deltochilum valgum rips millipedes in half and feasts on their insides. It's very competitive for the dung beetles and over 80 species are sometimes competing for the same feces.This competition is why the beetle has evolved.
Trond Larson of Princeton University was curious about the feeding habits and set up baited traps with dung, carrion(dean or rotting flesh), fruits and fungus. Over 11 months they observed 132 species and over 100,000 individuals. The D. valgum was the only species that only ate the millipedes.
Seen using infrared cameras, D. valgum's method of attack 8-millimeter-long beetle wedging its serrated head between the millipede's segments and splitting its prey's body in two. Afterward, the beetle dismantles the rest of the millipede and eats it up. D. valgum can kill prey up to 13 times its own size thanks to subtle body adaptations, including its wedged head and hind legs adapted to hold the millipede and drag it apart. These adaptations mean that there is potential for a outburst of a new predatory dung beetle species. It's a spectacular finding says biologist Armin Moczek of Indiana University, Bloomington. Millipeeds have a high proportion of fecees iside them so if the dung beetle is eating their insides it is essentially eating dung.
Posted By: Samantha DeBiasio(week 2)
Update: Feb 20,2009
Some adaptions that have formed are the head changing. Most dung beetles have broad heads to help them push and mold dung balls, D. valgum had a narrow elongated head for feeding(video) on the insides of millipeeds. They use a sharp, shield-like plate on the top of their heads like a chisel to decapitate their prey.
Some dung beetles have responded by broadening their tastes to include rotting fruit, fungi and dead animals. A couple of species will even kill queen leafcutter ants to supplement their dung-based diets. The researchers noted that monor adaptations to the beetles bodies led to large behavioral changes, like eating millipeeds. these adaptations came about possibly because of competition with relatives.
The beetles didnt dine on site they prefer dragging the dead millipeeds to another location. This is the first known case of an obligate predatory dung beetle.This was Found Jan 22,2009. this is not the first time the dung beetle has been shown to be more sophisticated, in 2006 it was found they were picky eaters by researchers in Kuwait who won an Ig Nobel Prize. Also the Dung beetle was the first animal found to use moonlight to navigate.
Hutchinson-Gilford Progeria Syndrome is an extremely rare disease that causes the body to age at a rate 8 to 10 quicker than normal. Caused by one tiny hiccup in a child’s genetic code, Progeria has life-changing consequences. The cells of these children deteriorate at such an accelerated rate that by the age of twelve the majority have had a heart attack, stroke, and/or disabling arthritis. The number one killer of children with Progeria isatherosclerosis or cardiovascular disease. And the average age of death is 13. Children with this disease share other ailments as well including premature baldness, high blood pressure, thin bone structures, and short stature. These children’s brains, however, develop completely and have no adverse affects. This phenomenon occurs because the protein that causes Progeria is not expressed in brain cells.
In October 2002, The Progeria Research Foundation's Genetics Consortium discovered that Progeria is caused by a mutation in the protein LMNA (Lamin-A). A mutation anywhere on the protein will cause Progeria, but 70% of the cases are caused by one particular alteration. Lamin-A is the protein that forms the inside of the nucleus. It makes a spider web type structure that holds all the DNA strands in place and keeps the nucleus spherical. When Lamin-A is removed the nucleus becomes amorphous and the DNA becomes scrambled and unable to be read efficiently.
Even more recently, a drug has been developed and 25 brave families have signed up for the first test. Originally developed to aid cancer patients, doctors are hoping the drug will be able to reverse nucleus abnormalities. It has worked well in tests with mice in laboratories, but never before been used on human subjects. This presents hope to patients and a whole new chapter for this extraordinary disease.
Progeria is very rare and only about 100 people have been diagnosed since the discovery of the disease itself in 1886 by its namesakes. However, the disease is dominant and there is a family in India today who has had five children diagnosed with Progeria, two of which have already passed away.
Sources:
I found out about Progeria through a program on the Discovery Health channel called Hayley’s Story. Hayley Okines is a 12-year-old girl living in England with advanced Progeria.
They extracted the original Neanderthal DNA from a bone found in Croatia that is said to be 38,000 years old. The scientists are currently taking DNA from five other bones which will allow them to build up a library of Neanderthal genomes. These genomes will be used to compare Neanderthal DNA to human DNA.
Neanderthals are extinct and are the closest relative to the human species. Humans and Neanderthals are part of the Homo genus. Humans are classified as Homo sapiens while Neanderthals are classified as Homo neanderthalensis. The anatomy of the two species are very similar. It was once believed that there were not seperate species but rather subspecies and were referred to as Homo sapiens neanderthalensis and Homo sapiens sapiens. It is really interesting to see how similar their anatomy and DNA truly are.
There were certainly periods of coexistence between these two species and it is possible that this genome project will provide proof that there was interbreeding. Interbreeding might have been possible because the species genomes have 99% in common. The team of scientists state that their genome is precise enough to be published because the new sequencing technique does not need to be rechecked.
Posted by: Willow Alves (1)
UPDATE:
This particular Neanderthal bone was found in a cave located in Croatia. It is not known for certain whether humans and neanderthals actually interbred. Scientists are hoping to find proof in their DNA genome. Interbreeding is thought to have been possible because Neanderthals are our closest evolutionary relative. Experts believe that the DNA genome shows limited or no evidence of interbreeding but they still say that it could have been possible. It is said that interbreeding most likely happened rarely and if it did seems to have had a very minimal effect on the variation of humans.
It is not known if interbreeding between the two species would produce a sterile second generation but it is possible that it could be similar to a horse and donkey creating a mule. However, if the abnormalities in the genes from Europeans or Africans are actually directly linked to the Neanderthal that that would prove that interbreeding happened. In that case it would be more like a male lion and female tiger creating a potential fertile liger.
We have all seen contemporary humans with protruding jaw line, protruding low brow ridge, extremely hairy, or with a unibrow. There were clearly differences between Neanderthals and humans, could these human characteristics be passed down to Neanderthals’ descendants? I think all the speculations and theories are really interesting, but as of right now nothing has been proven.
Upon working with an equine veterinarian who specializes in lameness of performance horses, I've seen many horses with issues really difficult to diagnose including my own ex-race horse with his fair share of problems. It always interests me to hear about new technologies and diagnostic techniques. The mathworks, a software company my mother works for, often brings in guest-speakers who use their products. A few months ago my mother was able to attend a seminar with the inventor of EquuSys and forwarded me the website which I will now share with all of you.
EquuSys is a sensor system that uses telemetry and informatics to help diagnose, and rehabilitate equine lameness. By attaching these tiny sensors to boots (already normally worn by the horse) data is taken and interpreted to evaluate a horses movement which can in turn be used to help diagnose even subtle lameness or narrow down the main cause of a multiple-leg lameness. A multiple leg lameness is sometimes extremely difficult to diagnose in that an injury in one leg can set off an even more visible lameness in another leg. When the secondary lameness is treated without the primary treated first the cycle is hard to break and both will continue to aggravate each other.
Not only can EquuSys be used in diagnostics, it can also assist in conditioning the performance horse which can in turn help prevent injury from happening in the first place. Although extremely helpful in understanding equine injuries, EquuSys is still mainly only used in research and extremely costly for you average practitioners. Seems I'll be keeping with the old fashioned techniques for my own horse's issues.
UPDATE:
Lameness is indeed a term used to describe a condition where the horse moves irregularly. It is a general term and can be caused by many different things. Normally an equine veterinarian's time diagnosing and treatment is already extremely expensive. The average horse is either not insured or only covered for major medical. So in answer to many of your questions, I am doubtful this will be something that becomes more popular in the future for the average horse owner. Not only is it expensive equipment, its use is time consuming which will also add to the cost.
The mosquito is the only insect capable of carrying the human malaria parasite, known as plasmodia. After penetrating the skin with her syringe-like mouth through a thin layer of fat and into the capillaries, the infected female mosquito of the genus Anopheles begins to drink the blood. To prevent the blood from coagulating, she oils the affected area with her saliva. At this point in her feeding, tiny malaria worms that she carries in her salivary glands are sprayed into the victim’s bloodstream. About 50,000 are inserted, but it only takes one to kill a child.
From the mosquito’s salivary glands to the victim’s circulatory system, the parasite travels to the liver where malaria makes itself comfortable and begins to digest the liver cells immediately. While the parasite eats and multiplies, the victim shows no symptoms and feels no change in his or her body for roughly a week. During this week of silence, each falciparum has multiplied itself 40,000 times. After being digested through and through, the liver cells explode and the parasites are let into the bloodstream entering each red blood cell devouring and proliferating.
In this second week, the body starts to feel ambushed. The victim’s temperature begins to rise in order to cook away the parasite and shivers in order to produce more heat. It is then followed by drenching sweats in order to cool the victim back down. While the victim goes through this agonizing cycle, there are billions of parasites in the blood, continuing to multiply. Meanwhile, the infected cells pass through the capillaries of the brain and latch on so as to not pass through the spleen, whose job is to clean blood by destroying tainted cells. At this point the brain starts to swell; this is known as cerebral malaria.
Scientists around the world have been desperately trying to find new drugs to stop the malaria parasite and prevent the disease from spreading. Malaria is spread so widely in Africa, it is very difficult to control, even with all the international funding and private donations. There has been an anti-malaria gene located in sickle-cell anemia patients demonstrating that those with HbC are less likely to become sick with malaria compared to normal HbA people. However, this mutation is not more prevalent in Africa because the negative effects of sickle cell anemia outweigh the resistance to malaria.
Update:
When the body starts to break down physically, the parasites have destroyed so many oxygen-carrying red cells that too few are left to sustain vital functions. The lungs fight for breath, and the heart struggles to pump. The blood acidifies and many brain cells die.
Sickle-cell anemia is the result of a faulty hemoglobin molecule. Hemoglobin molecules of homozygotes behave abnormally after releasing their oxygen. Instead of remaining soluble in the cytoplasm, they combine to form long fibers that deform the red blood cell from a normal biconcave disk to a sickle shape.
The deformed cells clog the small blood vessels, reducing oxygen flow to the tissues and giving rise to muscle cramps, shortness of breath and fatigue. The sickle cells are also very fragile and easily broken. Homozygotes are resistant to malaria because when the parasites try multiplying in the cell, the sickle cell breaks down before the malaria parasite can proliferate.
In areas where malaria is endemic, heterozygotes are better able to survive and pass on their genes than are either type of homozygote. Homozygotes sickle cell individuals often die of sickle cell disease while those who are normal homozygotes often die of malaria. Heterozygotes are relatively immune to both conditions. Understanding how the gene prevents severe malaria could lead to the development of protective drugs.
Ozone Layer has mixed feelings towards Climate Change
While we may not see it or often think of it, the ozone layer is one of the most vital parts of the global ecosystem. It protects all living things from harmful cosmic UV-B radiation emitted from the sun. During the 1970s, a concern about the depletion of the ozone layer began to spread around the globe. Scientists wondered what was responsible for what could have become a global catastrophe, as loss of ozone could spell serious trouble for animals and plants alike. They finally confirmed that CFCs (chlorofluorocarbons) were largely responsible for the loss of ozone in earths statosphere. At the time, CFCs represented a large chunk of commercial propellants and strengthening agents, used in everything from some (even now) Albutorol inhalers, paint sprayers and mechanical lubricants to aerosol cans, pesticides and rigid foams. The US has since banned many products containing CFCs.
But how do we stop ozone depletion? Scientists think the very chemicals theorized to be the major culprit of the global warming crisis, greenhouse gases, actually slow the rates of chemical change that destroys ozone. This shows us that the greenhouse effect is actually beneficial to ozone. But, changing air currents induced by the effect can also have a negative effect on the ozone layer, as researchers from the University of Maryland found.
They ran a climate model simulator and found that the changing air circulation patterns induced an increase in air flow around Australia and argentina, delaying the ozone layers' recovery by slowing the rate of ozone production. The US, however, along with other northerly countries will see enhanced recovery of ozone as air currents slow.
The most frightening consequence of this is that UV-B radiation is responsible for skin damage that can lead to skin cancer (the radiation fractures DNA and RNA molecules and induce mutations that can lead to uncontrolled cell proliferation (cancer)). A loss of ozone means more UVB gets through the atmosphere in places like Peru, Argentina and Chile, posing potential problems for lightly skinned individuals in those countries.
These findings, however, are controversial. Further research modeling is needed, as labs in the UK have found conclusions not congruent to those proposed by the Maryland lab.
This Little Piggy Went to the Market, and This Little Piggy Found a Cure
Cystic Fibrosis (referred to as CF) is a chronic disease inherited when two carrier parents both pass their mutated genes onto their child. Currently affecting the lungs and digestive systems of around 30,000 people in the United States alone, it is known as the most common genetic disease in Caucasians. Through the years scientists have been able to make huge break-throughs in CF research, thus increasing the average life expectancy of a CF patient from 10 years to the most recent statistic, 37 years of age.
Most recently, in 2008, a researcher from the University of Missouri, with help from staff at the University of Iowa, has found a way to naturally breed swine to produce piglets with CF. Due to the fact that the physiology of a pig is so close to humans, the piglets display the same symptoms as a newborn with CF. The piglets are flown to Iowa and are immediately placed with physicians who operate on them as they would a newborn with CF. So far, they have been able to get the piglets through the initial stages of the disease allowing them to grow and develop the fatal lung disease caused by CF later in life. Once the lung disease has developed, they can further their testing and answer questions that have never been touched.
Coming from a family that lost a relative to CF and has two others currently fighting the battle against it, this struck me as unbelievable. I'm usually not an advocate for animal testing, but the break-through with these piglets has potential to make a giant leap in CF research. The only other way to perform these kinds of tests is to experiment on children with the disease. Scientists have assured that the piglets are treated with care and are not harmed, only helped. The pig testing gives families with CF patients, like mine, more hope than ever before.
Posted by Crystal Cabral (1)
Update February 13, 2009: I've been getting a few comments on what treatments CF patients actually go through. Newborns usually go through testing for the disease they check trypsin (a digestive enzyme) levels in the blood. Also other digestive and genetic testing are done on the newborn patients as well. Because CF mainly affects the lungs of the patients, at the first sign of this beating on the patients chest or "postural drainage and percussion" helps encourage coughing. Patients see doctors and therapists that perform respiratory therapy and receive immunizations regularly. Most CF patients wait for a lung transplant but in the mean time are hospitalized regularly for mechanical ventilation. Surgical procedures are usually made on the livers of CF patients due to the thick secretions that block the bile ducts in the liver causing Cirrhosis. In some situations the gall bladder function is extremely low and it must be removed. Another side affect of the disease is insulin-dependent diabetes in which case the patient goes through normal routine of a diabetic, but their pancreas must be watched closely and need to take pancreatic enzyme replacement pills with every meal. The patients must take their medication regularly and be hospitalized and watched closely in anticipation of a successful lung transplant to occur at some point in their lives. For more information on CF patients, treatment, testing, and about the disease in general visit www.cff.org.
In 1996, researchers cloned Dolly the sheep. This was accomplished using a technique called somatic cell nuclear transfer (SCNT). The process involves the transfer of a nucleus, which contains the DNA to be cloned, into a nucleus-free egg to stimulate the replication of the DNA. But, can a human be cloned using this technique? Scientists, ethicists, and politicians have wondered about the same idea, but many have rejected this idea as it trespasses upon unethical boundaries. To test this controversial idea, Advanced Cell Technology researchers applied SCNT on human eggs. Robert Lanza, the ACT chief executive, claimed that the human eggs effectively reprogrammed the human DNA so that gene activity mirrored that in normal human embryos over the first few days of development. However, the lack of human eggs had hindered the further development and understanding of SCNT. Therefore, scientists have started to use a hybrid approach. Instead of using human eggs, ACT researchers transplanted human DNA into animal eggs. Since no cells from such hybrid embryos would be transplanted into people, ACT researchers hoped to derive stem cell lines to further explore genetic diseases. To the researchers’ dismay, the hybrid approach was unsuccessful. The report indicated that the hybrid embryos were unable to activate the developmental genes needed for stem cell formation, such as those activated in human embryos. Some critics disagree with this statement, claiming that not enough time was allotted for the hybrid embryos to develop. Despite the failure of the hybrid approach, ACT chief executive, Robert Lanza, indicates that cloning an actual person is indeed possible.
Posted by Saad Choudhry (1)
Update (February 13, 2009):
Human cloning is still a trivial topic. Most people view human cloning as being unethical and have rejected this idea. Personally, I fail to disagree with this point of view. First of all, the process of somatic cell nuclear transfer (SCNT) has not yet produced human somatic embryonic stem cells. Adding more people to the gene pool is definitely out of the question. “A South Korean team famously claimed a few years ago to have made human embryonic stem cells using SCNT, but that cloning work was found to have been fraudulent.” Secondly, there is no telling what kind of complications/mutations that could arise with a cloned human embryo. Although human stem cell lines can be utilized to better study genetic diseases, the cons of human cloning outweigh the pros.
From an early age, people are instilled with the idea that milk does a body good; however, what has come to be known as "milk" today is actually an industrial byproduct called swill.
For centuries people drank "raw" milk (milk that has not undergone pasteurization) and experienced beneficial results. The indigenous African tribe, the Masai, for example, consume about a quart of raw milk each day and have an incredible low incidence of tooth decay due to living bacteria that thrive by not pasteurizing the milk. Raw milk aids in digestion and implements a healthy functioning immune system. Currently, the FDA issues public health warnings against drinking raw milk and is pushing legislation to make it illegal. So why the raw milk scare?
During the industrial revolution, large amounts of grain were processed resulting in a slop byproduct that was too costly to dispense of. The slop was then force fed to large scale dairy cows at an enormous economic profit. Cow's digestive systems are built on the basis of an all grass diet; thus when fed slop, the cows lost their hair, nails, teeth and their milk lacked prior nutrients such as calcium and appeared blue. To counter act the discoloration, chalk was added in order to look "milkier." Inasmuch, this cheaper method of making milk rose the infant mortality rate by 50% in the mid 1900's due to diarrhea and tuberculosis directly correlating back to the malnourished cow's "milk." The FDA turned to pasteurization, proven to kill bovine TB, as a scape goat letting swill prevail.
Pasteurization does kill the bacteria; however, the dead pathogens remain in the milk and eventually decay. A somatic cell count measures the white blood and mammary tissue cells that determine a cow's health. A healthy cow will produce about 50,000 to 100,000 somatic cells per ml. Cell counts above 300,000 signify an infection of the udder, linked to the pathogen Listeria. Cell counts of over 750,000 per ml. are allowed by the FDA and are then pasturized. "In the past 20 years, the FDA has recorded well over 200,000 cases of salmonella, hundreads of E. Coli infections, and most recently, Listeria, traced to pasteurized milk."
Buisnesses such as Kraft and JELL-O are strong lobbyists in Washington and can not affored to convert large scale dairy farms into sustainable raw milk farms. Human health should not suffer at the hands of economic profit. Raw milk contains high levels of beneficial bacteria and enzymes, omega 3s and 6s, and conjugated linoleic acid with antioxident properties. It also regulates cholesterol, increases calcium and protein absorbtion and helps heal arthritus and allergies including lactose intolerance.
As consumers, it is our duty to demand raw milk on the shelves in every grocery store. Although a bit more costly (raw milk goes for $5 a gallon and "swill milk" costs about $1.60) you definately get what you pay for.
There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.
