Sunday, March 28, 2010
Prospectus Workshop Summary
It was a pleasure reading the work of the members in my group, and also an education, since our interests lie in different areas of science. I did my best to give helpful and constructive criticism, although my classmates needed very little help. The quality of their work was impressive! I did give some helpful (I hope) suggestions about the methodological approach of the Literature Review, as well as pointing out a few grammatical erros, but other than that, there were no major areas of concern within my group. For myself, I worried mostly that my prospectus was too long and technical and that it would not be interesting enough. None of my group mates made any comments to that effect, so I left it pretty much intact except for some minor changes before posting my final paper as a Google doc. One of the things that was a bit cumbersome was some of the reformatting required when utilizing the wiki and google docs. All in all, it was a fairly painless process. The most difficult task for me was actually coming up with the questions for the review comments on the Research Design. The whole process has made me more confident with writing that is more technical than creative in nature. I think I've learned a great deal from this project.
Saturday, March 20, 2010
Research Problem
I don't think I posted this previously, so I'm going to go ahead and post it prior to inclusion in my Draft Research Prospectus (even though it still needs some work):
Autism or Autism Spectrum Disorder (ASD) is a prevalent neurological disorder, facing millions of children worldwide. Diagnosis is typically made in early childhood by trained professionals, based on a scale of specific characteristics established by the Autism Diagnostic Observation Schedule (ADOS) and Autism Diagnostic Interview – Revised (ADI-R), which developed only as recently as the 1990s. ASD can often be overwhelmingly devastating, with impairments in language, perception, cognitive development, and social interactions. (Abrahams and Geschwind 2008)
Identification of the cause(s) of ASD remains elusive. Unfortunately, many parents forego important immunizations for their children for fear that they will cause autism. However, a link between childhood immunizations and autism has not been proven. Rather, current scientific studies have indicated that there are possible genetic linkages which increase the susceptibility to the disorder, although environmental factors have not been completely ruled out. Chromosomal abnormalities, although rare, have also been shown to be a factor. (Weiss and Arking 2009) Additionally, there appears to be a crossover of genetic linkages between ASD and other neurological disorders, such as Obsessive-Compulsive Disorder and mental retardation. (Gregory et al 2009)
Several key questions need to be answered in order to effectively attack the problem of autism spectrum disorders. Can autism be diagnosed, and if so, how early? Is it possible that one day genetic counselors will able to identify factors during pregnancy? Could a test, similar to the PKU test conducted on newborns be developed in order to provide early intervention? Does genetic risk act alone or in concert with environmental factors?
It is clear that, although significant findings have been promising, more studies that involve both genetic and environmental factors are needed to narrow the focus. (Abrahams and Geschwind 2008) The rates of autism related disorders are clearly on the rise, and although we have been able to find effective therapies, the best outcomes require early diagnosis, early intervention and if possible, prevention. This proposal seeks to conduct a study which will address each of these issues equally.
Bibliography
Abrahams BS, Geschwind BS. Advances in autism genetics: on the threshold of a new neurobiology. Nat Rev Genet. [Internet] 2008 May:9(5):341-355. [cited 2010 Feb 26] Available from: http://www.nchi.nlm.nih.gov/entrez/query.fcgi?db=gene. Doi:10.1038/nrg2346.
Gregory SG, Connelly JJ, Towers AJ, Johnson J, Biscocho D, Markunas CA, Lintas C, Abramson RK, Wright HH, Ellis P, et al. Genomic and epigenetic evidence for oxytocin receptor deficiency in autism. BMC Medicine. [Internet] 2009, 7:62 [cited 2010 Feb 26] Available from: http://biomedcentral.com/1741-7015/7/62. Doi:10.1186/1741-7015-7-62.
Weiss LA, Arking DE & The Gene Discovery Project of Johns Hopkins & the Autism Consortium. A genome-wide linkage and association scan reveals novel loci for autism. Nature [Internet] 2009 8 Oct, 461. [cited 2010 Feb 26] Available from: http://nature.com/nature08490. Doi:10.1038/nature08490.
Autism or Autism Spectrum Disorder (ASD) is a prevalent neurological disorder, facing millions of children worldwide. Diagnosis is typically made in early childhood by trained professionals, based on a scale of specific characteristics established by the Autism Diagnostic Observation Schedule (ADOS) and Autism Diagnostic Interview – Revised (ADI-R), which developed only as recently as the 1990s. ASD can often be overwhelmingly devastating, with impairments in language, perception, cognitive development, and social interactions. (Abrahams and Geschwind 2008)
Identification of the cause(s) of ASD remains elusive. Unfortunately, many parents forego important immunizations for their children for fear that they will cause autism. However, a link between childhood immunizations and autism has not been proven. Rather, current scientific studies have indicated that there are possible genetic linkages which increase the susceptibility to the disorder, although environmental factors have not been completely ruled out. Chromosomal abnormalities, although rare, have also been shown to be a factor. (Weiss and Arking 2009) Additionally, there appears to be a crossover of genetic linkages between ASD and other neurological disorders, such as Obsessive-Compulsive Disorder and mental retardation. (Gregory et al 2009)
Several key questions need to be answered in order to effectively attack the problem of autism spectrum disorders. Can autism be diagnosed, and if so, how early? Is it possible that one day genetic counselors will able to identify factors during pregnancy? Could a test, similar to the PKU test conducted on newborns be developed in order to provide early intervention? Does genetic risk act alone or in concert with environmental factors?
It is clear that, although significant findings have been promising, more studies that involve both genetic and environmental factors are needed to narrow the focus. (Abrahams and Geschwind 2008) The rates of autism related disorders are clearly on the rise, and although we have been able to find effective therapies, the best outcomes require early diagnosis, early intervention and if possible, prevention. This proposal seeks to conduct a study which will address each of these issues equally.
Bibliography
Abrahams BS, Geschwind BS. Advances in autism genetics: on the threshold of a new neurobiology. Nat Rev Genet. [Internet] 2008 May:9(5):341-355. [cited 2010 Feb 26] Available from: http://www.nchi.nlm.nih.gov/entrez/query.fcgi?db=gene. Doi:10.1038/nrg2346.
Gregory SG, Connelly JJ, Towers AJ, Johnson J, Biscocho D, Markunas CA, Lintas C, Abramson RK, Wright HH, Ellis P, et al. Genomic and epigenetic evidence for oxytocin receptor deficiency in autism. BMC Medicine. [Internet] 2009, 7:62 [cited 2010 Feb 26] Available from: http://biomedcentral.com/1741-7015/7/62. Doi:10.1186/1741-7015-7-62.
Weiss LA, Arking DE & The Gene Discovery Project of Johns Hopkins & the Autism Consortium. A genome-wide linkage and association scan reveals novel loci for autism. Nature [Internet] 2009 8 Oct, 461. [cited 2010 Feb 26] Available from: http://nature.com/nature08490. Doi:10.1038/nature08490.
Sunday, February 28, 2010
Freewrite #5 - State of Research Prospectus
I found that working on the Literature Review this week was very helpful as far as organizing my thoughts on my Research Prospectus. I now have a better idea of what kinds of studies have been done on both the genetic and environmental links to autism. I’m still unsure what it is that I’d propose for the experiment, although I do know what areas I would like to focus on. The literature that is out there was very technical in nature, and I almost felt like this was something I’m not yet ready for in my educational career. However, even though I was not familiar with the technical terms and procedures covered in the studies I reviewed, I found I was able to understand all of the concepts. I will probably be doing more of this a year or so down the road, since I’ll be entering my junior year in the fall and planning for graduate studies, so I’m sure this will be very beneficial to me in the long run. I started this course not having a clue as to what I would propose, but already I have a much clearer picture.
Freewrite #4 - Open Topic: Is it Spring Break Yet?
This has been a most exhausting week! I’m looking forward to spring break, although it won’t really be that much of a break other than not having to commute to classes all week. I have two lab reports, an extra credit paper and the assignments for English 302 all due the week after the break, not to mention quizzes to study for and reading to catch up on. Let me rephrase that first sentence – this has been a most exhausting semester! I can’t believe it’s already spring break, though. It really doesn’t seem like it’s been that long. I wish I could take off for the week, but I had planned to spend it getting the taxes done (besides the school work). I have gotten so behind on bookkeeping for my business since I returned to school, I don’t know how I’m going to get it all done in time. It’s always nice to get the refund, though, so I know it will all be worth it. This is my constant juggle: schoolwork, family, business, pets. Oh yeah, and there’s that other thing I’ve been neglecting lately – sleep! That’s where I’m heading right now...
Freewrite #3 - Reading the Literature Review
The Literature Review I read recently related to the topic I wrote about for my Draft Literature Review assignment, autism. It covered quite a few more article references than mine did, and was rather long and thorough. The subject material was organized both methodologically and chronologically to give a picture of how studies progressed over the years. It was quite different in structure and content from the article I used for my Anatomy of a Journal Article assignment. In that case, the article reflected one study and was highly technical in content. I’d have to say that the Literature Review is not that dissimilar from other research papers I’ve written in the past, except for the strictly methodological organization and the number of required sources. I found it quite a bit more work to review so many technical articles and then write about them in a way that extracted only the most important details. It was definitely a challenge!
Sunday, February 21, 2010
Science Article Summary #15
Walton, D. “Archbishop in genome health study.” BBC News. February 18, 2010. BBC MMX [Internet]. [accessed Feb 21, 2010] Available from:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8519954.stm
Archbishop in genome health study
In a study on genetic diversity and health, a group of scientists analyzed the genomes of five South Africans, including Archbishop Desmond Tutu. Their findings, which were published in the journal Nature, provided valuable insight into the connection between health and genetics.
The Archbishop, and four indigenous hunter-gatherers from different parts of the Kalahari region were the subjects of the study. Each were about 80 years old and had lengthy health records available for review by researchers. Archbishop Tutu himself has had a history of both cancer and TB and was quite relieved to learn that he had no genetically-linked diseases to worry about.
South Africans have not often been involved in medical trials in the past. However, there are many advantages to be had, since they are genetically distinct from Europeans, Asians and West Africans and show a great deal more diversity. Much of this diversity may be explained by adaptation to the environment, lifestyle and diet. For instance, the allele associated with light skin color as well as one related to the digestion of milk were not present in their genes. They are also missing an allele which provides resistance to malaria. Since the Kalarahi desert is mostly free of malaria, the Bushmen living there might not survive if they were to move to another location where malaria is more prevalent.
Archbishop Tutu is very much in support of the study of genetic diversity, which he believes is one of humanity’s greatest assets. After all, Africa is one of the most diverse environments on earth, and the origin of modern man.
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8519954.stm
Archbishop in genome health study
In a study on genetic diversity and health, a group of scientists analyzed the genomes of five South Africans, including Archbishop Desmond Tutu. Their findings, which were published in the journal Nature, provided valuable insight into the connection between health and genetics.
The Archbishop, and four indigenous hunter-gatherers from different parts of the Kalahari region were the subjects of the study. Each were about 80 years old and had lengthy health records available for review by researchers. Archbishop Tutu himself has had a history of both cancer and TB and was quite relieved to learn that he had no genetically-linked diseases to worry about.
South Africans have not often been involved in medical trials in the past. However, there are many advantages to be had, since they are genetically distinct from Europeans, Asians and West Africans and show a great deal more diversity. Much of this diversity may be explained by adaptation to the environment, lifestyle and diet. For instance, the allele associated with light skin color as well as one related to the digestion of milk were not present in their genes. They are also missing an allele which provides resistance to malaria. Since the Kalarahi desert is mostly free of malaria, the Bushmen living there might not survive if they were to move to another location where malaria is more prevalent.
Archbishop Tutu is very much in support of the study of genetic diversity, which he believes is one of humanity’s greatest assets. After all, Africa is one of the most diverse environments on earth, and the origin of modern man.
Science Article Summary #14
Gill, V. “Singing ‘rewires’ damaged brain.” BBC News. February 21, 2010. BBC MMX [Internet]. [accessed Feb 21, 2010] Available from:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8526699.stm
Singing ‘rewires’ damaged brain
There is new hope for stroke patients who have damaged the part of the brain responsible for speech. If one’s “speech centre,” which is on the left side of the brain, is damaged by a stroke, they can learn to use their “singing centre” on the right side of the brain.
At the annual meeting of the American Association for Advancement of Science (AAAS) in San Diego, researchers presented finding from their ongoing clinical trial led by Gottfried Schalaug, a neurology professor at Beth Israel Deaconess Medical Center and Harvard Medical School. The trial is focused on how the brain responds to what they refer to as “melodic intonation therapy.”
This therapy is not new in the medical field. It was first used on stroke patients who had damaged the left side of their brain, but were still able to sing. This study combines the melodic intonation therapy with brain imaging so that researchers can actually see what’s happening as patients sing their words. Brain imaging studies have previously shown that the “singing centre” in the right side of the brain of professional singers is overdeveloped. It is believed that it can be developed in stroke patients through therapy. Brain imaging provides a means for monitoring the activity in the brain and the progress made with therapy.
Dr. Nina Kraus, a neuroscientist from Northwestern University has also conducted studies of the brain’s responses to music by using electrodes attached to the scalp. Since neurons function with electrical impulses, they can be played back through speakers to hear how the brain processes sounds. Dr. Kraus suggests that musical training can enhance the performance of reading and other tasks as well as speech and should be encouraged as a part of a child’s education.
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8526699.stm
Singing ‘rewires’ damaged brain
There is new hope for stroke patients who have damaged the part of the brain responsible for speech. If one’s “speech centre,” which is on the left side of the brain, is damaged by a stroke, they can learn to use their “singing centre” on the right side of the brain.
At the annual meeting of the American Association for Advancement of Science (AAAS) in San Diego, researchers presented finding from their ongoing clinical trial led by Gottfried Schalaug, a neurology professor at Beth Israel Deaconess Medical Center and Harvard Medical School. The trial is focused on how the brain responds to what they refer to as “melodic intonation therapy.”
This therapy is not new in the medical field. It was first used on stroke patients who had damaged the left side of their brain, but were still able to sing. This study combines the melodic intonation therapy with brain imaging so that researchers can actually see what’s happening as patients sing their words. Brain imaging studies have previously shown that the “singing centre” in the right side of the brain of professional singers is overdeveloped. It is believed that it can be developed in stroke patients through therapy. Brain imaging provides a means for monitoring the activity in the brain and the progress made with therapy.
Dr. Nina Kraus, a neuroscientist from Northwestern University has also conducted studies of the brain’s responses to music by using electrodes attached to the scalp. Since neurons function with electrical impulses, they can be played back through speakers to hear how the brain processes sounds. Dr. Kraus suggests that musical training can enhance the performance of reading and other tasks as well as speech and should be encouraged as a part of a child’s education.
Science Article Summary #13
BBC News. “Drugs ‘could stop spread of Aids’.” BBC MMX. February 21, 2010. [Internet]. [accessed Feb 21, 2010] Available from:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8526690.stm
Drugs ‘could stop spread of Aids’
Top scientists, including Dr. Brian Williams of Sacema, now believe that anti-retroviral treatments (ARVs) and universal testing could stop the spread of Aids in areas such as South Africa within the next five years. Although it would cost between $2 – 3 billion per year to deliver these drugs to the more than 6 million HIV-positive patients in South Africa, even if 30% are able to receive the drugs, it would help prevent transmission of the virus.
In addition to the ARVs used to treat the disease, scientists are still working on a vaccine for Aids, but it may be a long time before an effective one is achieved. Dr Williams spoke about HIV and Aids at the annual meeting of the American Association for the Advancement of Science (AAAS). He believes that these new drugs are helping to keep many of infected individuals alive, while reducing their viral load up to 2,000 times, thereby achieving an almost non-infectious state.
The drugs work best when given early in the course of infection and may not be as effective in later stages of Aids. It unfortunately has no effect on HIV transmission because most infected individuals have already transmitted the virus by the time they receive ART treatment.
Clinical trials have already begun in the US, Canada and sub-Saharan Africa. Dr. Williams hopes that trials in South Africa can begin in the next one or two years, since it can take up to five years to make sure all of the HIV positive individuals there receive ARV treatment. The US National Institute of Allergy and Infectious Disease is about to begin trials in New York and Washington DC in areas that have an HIV rate similar to that in Africa. Once these trials are conducted, they can then move forward with trials in South Africa.
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8526690.stm
Drugs ‘could stop spread of Aids’
Top scientists, including Dr. Brian Williams of Sacema, now believe that anti-retroviral treatments (ARVs) and universal testing could stop the spread of Aids in areas such as South Africa within the next five years. Although it would cost between $2 – 3 billion per year to deliver these drugs to the more than 6 million HIV-positive patients in South Africa, even if 30% are able to receive the drugs, it would help prevent transmission of the virus.
In addition to the ARVs used to treat the disease, scientists are still working on a vaccine for Aids, but it may be a long time before an effective one is achieved. Dr Williams spoke about HIV and Aids at the annual meeting of the American Association for the Advancement of Science (AAAS). He believes that these new drugs are helping to keep many of infected individuals alive, while reducing their viral load up to 2,000 times, thereby achieving an almost non-infectious state.
The drugs work best when given early in the course of infection and may not be as effective in later stages of Aids. It unfortunately has no effect on HIV transmission because most infected individuals have already transmitted the virus by the time they receive ART treatment.
Clinical trials have already begun in the US, Canada and sub-Saharan Africa. Dr. Williams hopes that trials in South Africa can begin in the next one or two years, since it can take up to five years to make sure all of the HIV positive individuals there receive ARV treatment. The US National Institute of Allergy and Infectious Disease is about to begin trials in New York and Washington DC in areas that have an HIV rate similar to that in Africa. Once these trials are conducted, they can then move forward with trials in South Africa.
Science Article Summary #12
American Friends of Tel Aviv University. “Pinch Away Pain: Scorpion Venom Could Be an Alternative to Morphine.” Science Daily. February 21, 2010. [Internet]. [accessed Feb 21, 2010] Available from:
http://www.sciencedaily.com/releases/2010/02/100216163341.htm
Pinch Away the Pain: Scorpion Venom Could Be an Alternative to Morphine
Everyone knows that scorpions are poisonous and that one sting could deliver a dangerous dose of deadly venom, but could that venom be effectively used as an alternative to addictive painkillers such as morphine? According to Prof. Michael Gurevitz of Tel Aviv University’s Department of Plant Sciences, he believes it can.
Prof. Gurevitz has studied the peptide toxins in scorpion venom with regard to their interactions with the sodium channels of nervous and muscular systems. Mammals have nine of these sodium channels, not all of which deliver pain signals to our brain. Some of the peptide toxins in scorpion venom are programmed to interact with particular sodium channel subtypes in mammals, while others are programmed to interact with insects and other invertebrates. It is hoped that through genetic engineering, scientists may be able to manipulate these toxins to effectively be used as a potent painkiller, while eliminating or reducing harmful side effects.
The Chinese are way ahead of us when it comes to the use of natural medicines. They practice what we refer to as “alternative medicine,” using nature to fight disease and in some cases to fight pain. For hundreds of years, they have been using scorpion venom as an analgesic. If we can develop a safe and effective, natural medicine from scorpion venom, it could be a superior replacement to dangerous, addictive drugs such as morphine
http://www.sciencedaily.com/releases/2010/02/100216163341.htm
Pinch Away the Pain: Scorpion Venom Could Be an Alternative to Morphine
Everyone knows that scorpions are poisonous and that one sting could deliver a dangerous dose of deadly venom, but could that venom be effectively used as an alternative to addictive painkillers such as morphine? According to Prof. Michael Gurevitz of Tel Aviv University’s Department of Plant Sciences, he believes it can.
Prof. Gurevitz has studied the peptide toxins in scorpion venom with regard to their interactions with the sodium channels of nervous and muscular systems. Mammals have nine of these sodium channels, not all of which deliver pain signals to our brain. Some of the peptide toxins in scorpion venom are programmed to interact with particular sodium channel subtypes in mammals, while others are programmed to interact with insects and other invertebrates. It is hoped that through genetic engineering, scientists may be able to manipulate these toxins to effectively be used as a potent painkiller, while eliminating or reducing harmful side effects.
The Chinese are way ahead of us when it comes to the use of natural medicines. They practice what we refer to as “alternative medicine,” using nature to fight disease and in some cases to fight pain. For hundreds of years, they have been using scorpion venom as an analgesic. If we can develop a safe and effective, natural medicine from scorpion venom, it could be a superior replacement to dangerous, addictive drugs such as morphine
Science Article Summary #11
Rockefeller University. “Human Genetic Vulnerabilities May Underlie Infection Diseases, Scientist Argues.” Science Daily. February 21, 2010. [Internet]. [accessed Feb 21, 2010] Available from:
http://www.sciencedaily.com/releases/2010/02/100219204419.htm
Human Genetic Vulnerabilities May Underlie Infection Diseases, Scientist Argues
At the annual conference of American Association for the Advancement of Science (AAAS) on February 19, 2010, scientist Jean Laurent Casanova of Rockefeller University gave a talk entitled “Inborn Errors of Innate Immunity in Humans.” Casanova is currently conducting research on two infectious diseases, pneumococcal disease and herpes simplex encephalitis.
Casanova presented evidence at the symposium that how members of a population respond to infectious diseases such as these are dependent upon on their underlying genetic vulnerabilities. In other words, while a microbe can infect someone, whether or not that person can fight the infection depends on the defense mechanisms present in his or her genes.
Not all microbiologists agree on the subject of genetic vulnerabilities. Many others believe that infectious diseases are strictly caused by environmental factors. Immunologists, in particular, doubt that immunological molecules would target a narrow range of infectious microbes.
Whether disease happens due to genetic or environmental factors seems to be the basis for the disagreement among scientists. Casanova hopes to continue his work in finding the genetic basis of infectious diseases so that we may better understand how to effectively treat them.
http://www.sciencedaily.com/releases/2010/02/100219204419.htm
Human Genetic Vulnerabilities May Underlie Infection Diseases, Scientist Argues
At the annual conference of American Association for the Advancement of Science (AAAS) on February 19, 2010, scientist Jean Laurent Casanova of Rockefeller University gave a talk entitled “Inborn Errors of Innate Immunity in Humans.” Casanova is currently conducting research on two infectious diseases, pneumococcal disease and herpes simplex encephalitis.
Casanova presented evidence at the symposium that how members of a population respond to infectious diseases such as these are dependent upon on their underlying genetic vulnerabilities. In other words, while a microbe can infect someone, whether or not that person can fight the infection depends on the defense mechanisms present in his or her genes.
Not all microbiologists agree on the subject of genetic vulnerabilities. Many others believe that infectious diseases are strictly caused by environmental factors. Immunologists, in particular, doubt that immunological molecules would target a narrow range of infectious microbes.
Whether disease happens due to genetic or environmental factors seems to be the basis for the disagreement among scientists. Casanova hopes to continue his work in finding the genetic basis of infectious diseases so that we may better understand how to effectively treat them.
Saturday, February 20, 2010
Science Article Summary #10
University of California – San Diego. “Biologists Discover How Biological Clock Controls Cell Division in Baceria.” Science Daily. February 19, 2010. [Internet]. [accessed Feb 20, 2010] Available from:
http://www.sciencedaily.com/releases/2010/02/100218125154.htm
Biologists Discover How Biological Clock Controls Cell Division in Bacteria
As reported in the February 19, 2010 issue of the journal Cell, biologists have discovered the biochemistry of the timing of cell division in all living organisms, controlled by their biological clocks. Susan Golden, a biology professor at UC San Diego, headed the study, which focused on how the circadian clock is different in bacteria than in other life forms.
Golden’s team of researchers looked at how the biological clock regulates when a cell divides. Bacteria cells have a four-hour period in which no division occurs. Structural changes in the key protein that controls this period were identified. With the help of time-lapse microscopy, the team discovered that three bacterial clock proteins, KaiA KaiB, and KaiC control the action of another protein, FtsZ, which prevents it from moving to the middle of the cell, where it forms a ring in preparation of cell division. After four hours, the three clock proteins allow this action of FtsZ to occur.
Both the cell cycle and circadian cycle operate in timed patterns, but appear to work together to perform cell division. Researchers learned how the two cycles interact, and that they work differently in bacteria than they do in eukaryotic organisms (plants, animals and fungi). Learning how these mechanisms work can help us to understand how the biological clock effects our sleep cycle and thereby help us to avoid related problems, such as weight control, sleep patterns and response to disease.
http://www.sciencedaily.com/releases/2010/02/100218125154.htm
Biologists Discover How Biological Clock Controls Cell Division in Bacteria
As reported in the February 19, 2010 issue of the journal Cell, biologists have discovered the biochemistry of the timing of cell division in all living organisms, controlled by their biological clocks. Susan Golden, a biology professor at UC San Diego, headed the study, which focused on how the circadian clock is different in bacteria than in other life forms.
Golden’s team of researchers looked at how the biological clock regulates when a cell divides. Bacteria cells have a four-hour period in which no division occurs. Structural changes in the key protein that controls this period were identified. With the help of time-lapse microscopy, the team discovered that three bacterial clock proteins, KaiA KaiB, and KaiC control the action of another protein, FtsZ, which prevents it from moving to the middle of the cell, where it forms a ring in preparation of cell division. After four hours, the three clock proteins allow this action of FtsZ to occur.
Both the cell cycle and circadian cycle operate in timed patterns, but appear to work together to perform cell division. Researchers learned how the two cycles interact, and that they work differently in bacteria than they do in eukaryotic organisms (plants, animals and fungi). Learning how these mechanisms work can help us to understand how the biological clock effects our sleep cycle and thereby help us to avoid related problems, such as weight control, sleep patterns and response to disease.
Science Article Summary #9
Public Library of Science. “Viruses helped shape human genetic variability.” Science Daily. February 19, 2010. [Internet]. [accessed Feb 20, 2010] Available from:
http://www.sciencedaily.com/releases/2010/02/100218203053.htm
Viruses Helped Shape Human Genetic Variability
Viruses are historically well-known as potential threats to human populations worldwide. A group of Italian scientists have used population geneticists to study variants in genes which may indicate susceptibility to, or protection from viral infections.
In the study, which consisted mainly of computer simulations, researchers looked at populations of different geographic areas who have been exposed to different groups of viruses. The hypothesis was that populations would develop increased resistance to those pathogens most prevalent in their geographic area. This would indicate that certain viruses would be targeted by natural selection and that variants in the human genome could help prevent infection or lessen the severity of related diseases. Populations of one geographic area would develop immunities different from those in other areas due to the particular viruses present.
Through this study, 139 human genes were found that modulate susceptibility to viral infections due to protein interactions between the genes and viruses. It is hoped that identification of responsible gene variants may help scientists develop new vaccines or cures for viral diseases. The approach of this study may also be used to identify susceptibility to infections contracted from other, non-viral pathogens.
http://www.sciencedaily.com/releases/2010/02/100218203053.htm
Viruses Helped Shape Human Genetic Variability
Viruses are historically well-known as potential threats to human populations worldwide. A group of Italian scientists have used population geneticists to study variants in genes which may indicate susceptibility to, or protection from viral infections.
In the study, which consisted mainly of computer simulations, researchers looked at populations of different geographic areas who have been exposed to different groups of viruses. The hypothesis was that populations would develop increased resistance to those pathogens most prevalent in their geographic area. This would indicate that certain viruses would be targeted by natural selection and that variants in the human genome could help prevent infection or lessen the severity of related diseases. Populations of one geographic area would develop immunities different from those in other areas due to the particular viruses present.
Through this study, 139 human genes were found that modulate susceptibility to viral infections due to protein interactions between the genes and viruses. It is hoped that identification of responsible gene variants may help scientists develop new vaccines or cures for viral diseases. The approach of this study may also be used to identify susceptibility to infections contracted from other, non-viral pathogens.
Science Article Summary #8
Gill, V. “Dolphins have diabetes off switch.” BBC News. February 20, 2010. BBC MMX [Internet]. [accessed Feb 20, 2010] Available from:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8523412.stm
Dolphins have diabetes off switch
New findings from scientists at the US National Marine Mammal Foundation indicate that bottlenose dolphins exhibit insulin resistance, similar to human diabetes. The difference is that in dolphins, this resistance is switched on and off. It is hoped that researchers can find a human equivalent to the “off switch” in dolphins.
Dolphins in a San Diego study were fed snacks continuously throughout the day, but not fed at night. Blood samples taken both during the day and after the overnight fast showed that the changes in the dolphins’ blood chemistry mimicked that in humans with diabetes. They found that insulin, which reduces glucose levels, had no effect on dolphins during the periods of fasting. In the morning, after being fed, dolphins switch back to their non-fasting state, automatically controlling blood glucose levels.
Evolution may explain how these mammals developed this mechanism in order to cope with a high-protein, low-carbohydrate diet of fish. Their large-sized brains require sugar, but since their diet is very low in sugar, they developed a way to conserve small levels present in their bodies. Other fish with smaller brains do not appear to have this mechanism, so the big brain may be a key factor in its development. However, it is suggested that even dolphins could potentially develop diabetes if fed a diet high in sugar.
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8523412.stm
Dolphins have diabetes off switch
New findings from scientists at the US National Marine Mammal Foundation indicate that bottlenose dolphins exhibit insulin resistance, similar to human diabetes. The difference is that in dolphins, this resistance is switched on and off. It is hoped that researchers can find a human equivalent to the “off switch” in dolphins.
Dolphins in a San Diego study were fed snacks continuously throughout the day, but not fed at night. Blood samples taken both during the day and after the overnight fast showed that the changes in the dolphins’ blood chemistry mimicked that in humans with diabetes. They found that insulin, which reduces glucose levels, had no effect on dolphins during the periods of fasting. In the morning, after being fed, dolphins switch back to their non-fasting state, automatically controlling blood glucose levels.
Evolution may explain how these mammals developed this mechanism in order to cope with a high-protein, low-carbohydrate diet of fish. Their large-sized brains require sugar, but since their diet is very low in sugar, they developed a way to conserve small levels present in their bodies. Other fish with smaller brains do not appear to have this mechanism, so the big brain may be a key factor in its development. However, it is suggested that even dolphins could potentially develop diabetes if fed a diet high in sugar.
Science Article Summary #7
Gill, V. “Sex Hormone trial for head injury.” BBC New. February 20, 2010. BBC MMX [Internet]. [accessed Feb 20, 2010] Available from:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8525777.stm
Sex hormone trial for head injury
A new medical trial led by Dr. David Wright was announced at the annual meeting of the American Association for the Advancement of Science. The study, which will involve 1000 patients at trauma centers in the US is focused on the use of natural progesterone to treat patients with severe head injuries.
Progesterone is a female sex hormone related to pregnancy, which was used in the first contraceptive pills. Studies have shown that the hormone supports normal development of neurons in the brain and has a protective effect on brain tissue that has been traumatized. The hormone tends to reduce the typical swelling associated with brain injuries and repair damaged neurons, thereby reducing the risk of death.
Although synthetic progesterone is now used in contraceptive pills, only the natural form appears to have the beneficial effects on brain injuries. Besides human progesterone, another, more potent natural form is available from yams (sweet potatoes). It is this form that is being used in trials. The progesterone-based drug has been approved by the FDA to be given as soon as possible after a head injury in order to achieve the maximum beneficial effect.
http://news.bbc.co.uk/go/pr/fr/-/2/hi/science/nature/8525777.stm
Sex hormone trial for head injury
A new medical trial led by Dr. David Wright was announced at the annual meeting of the American Association for the Advancement of Science. The study, which will involve 1000 patients at trauma centers in the US is focused on the use of natural progesterone to treat patients with severe head injuries.
Progesterone is a female sex hormone related to pregnancy, which was used in the first contraceptive pills. Studies have shown that the hormone supports normal development of neurons in the brain and has a protective effect on brain tissue that has been traumatized. The hormone tends to reduce the typical swelling associated with brain injuries and repair damaged neurons, thereby reducing the risk of death.
Although synthetic progesterone is now used in contraceptive pills, only the natural form appears to have the beneficial effects on brain injuries. Besides human progesterone, another, more potent natural form is available from yams (sweet potatoes). It is this form that is being used in trials. The progesterone-based drug has been approved by the FDA to be given as soon as possible after a head injury in order to achieve the maximum beneficial effect.
Science Article Summary #6
Zimmer, C. “Evidence Builds on Color of Dinosaurs.” The New York Times. February 4, 2010. NYTimes.com [Internet]. [accessed Feb 4 2010] Available from:
http://www.nytimes.com/2010/02/05science/05dino.html?ref=science
Evidence Builds on Color of Dinosaurs
Finally, scientists believe they have found evidence of the color of dinosaurs. Paleontologists have focused their attention on two dinosaurs in particular. The first, is Sinosauropteryx, who researchers say had a white-and-ginger striped tail. Another bird-like dinosaur appears to have even more colorful feathers.
Dr. Richard O. Prum, an evolutionary biologist at Yale has published a new study in Science. The focus of the research is on pigment-loaded sacs called melanosomes, which are found in fossils of bird feathers from millions of years ago. According to Prum, it is the shape and arrangement of melanosomes the produces the color in the feathers. British and Chinese scientists have also begun looking at feathered dinosaur fossils of Sinosauropteryx, where they also found melanosomes in tail bristles indicating reddish and white rings along the tail.
In addition to discovering the mechanism for color, the research also supports that birds are descendants of bipedal dinosaurs known as theropods. Chinese researchers at the Beijing Museum of Natural History and Peking University are now studying a 150 million year old species known as Anchiornis huxleyi, a chicken-sized theropod.
A study of Anchiornis’ melanosome patterns indicates that it had a crown of reddish feathers surrounded by dark grey feathers, and had reddish and black spots on its face, a grey body, and white limbs with black tips. Scientists believe the extravagant colors of Anchiornis served some sort of visual function, such as to attract mates and escape predators. Scientists expect to learn much more about the features of dinosaurs as they examine their fossils.
http://www.nytimes.com/2010/02/05science/05dino.html?ref=science
Evidence Builds on Color of Dinosaurs
Finally, scientists believe they have found evidence of the color of dinosaurs. Paleontologists have focused their attention on two dinosaurs in particular. The first, is Sinosauropteryx, who researchers say had a white-and-ginger striped tail. Another bird-like dinosaur appears to have even more colorful feathers.
Dr. Richard O. Prum, an evolutionary biologist at Yale has published a new study in Science. The focus of the research is on pigment-loaded sacs called melanosomes, which are found in fossils of bird feathers from millions of years ago. According to Prum, it is the shape and arrangement of melanosomes the produces the color in the feathers. British and Chinese scientists have also begun looking at feathered dinosaur fossils of Sinosauropteryx, where they also found melanosomes in tail bristles indicating reddish and white rings along the tail.
In addition to discovering the mechanism for color, the research also supports that birds are descendants of bipedal dinosaurs known as theropods. Chinese researchers at the Beijing Museum of Natural History and Peking University are now studying a 150 million year old species known as Anchiornis huxleyi, a chicken-sized theropod.
A study of Anchiornis’ melanosome patterns indicates that it had a crown of reddish feathers surrounded by dark grey feathers, and had reddish and black spots on its face, a grey body, and white limbs with black tips. Scientists believe the extravagant colors of Anchiornis served some sort of visual function, such as to attract mates and escape predators. Scientists expect to learn much more about the features of dinosaurs as they examine their fossils.
Science Article Summary #5
Enserink, M. “Gates Call for ‘Decade of Vaccines,’ Pledges Assault on Child Mortality.” ScienceInsider. January 29, 2010. [Internet]. [accessed Feb 4 2010] Available from:
http://blogs.sciencemag.org/scienceinsider/2010/01/gates-calls-for.html
Gates Call for “Decade of Vaccines,” Pledges Assault on Child Mortality
At the World Enconomic Forum’s annual meeting in Davos, Switzerland on January 29, 2010, Bill and Melinda Gates announced the launch of a campaign, “Decade of Vaccines,” help end child mortality in poor countries.
Currently, 79% of children in developing countries are fully vaccinated against diseases such as diphtheria, tentanus and petussis, which has already saved millions of lives. According to Johns Hopkins Bloomberg School of Public Health, if the number could be increased to 90%, an additional 7.6 million lives could be saved by 2020.
The Gates’ would like to also increase vaccination rates for other diseases, such as Haemophilus influenza type B, pneumococcal disease, and rotavirus, and to support vaccines currently being developed for malaria and tuberculosis.
The Gates’s announcement was well-received by global health leaders. Margaret Chan, director-general of the World Health Organization, called it “unprecedented,” and supported their efforts in a written statement that also called on other organizations to step up their efforts. The Gates foundation currently spends about $800 million annually on vaccine research and plans to raise that amount to $1 billion annually. It is hoped that the announcement by the Gates Foundation will encourage other organizations to fund research, development and education programs for vaccines.
http://blogs.sciencemag.org/scienceinsider/2010/01/gates-calls-for.html
Gates Call for “Decade of Vaccines,” Pledges Assault on Child Mortality
At the World Enconomic Forum’s annual meeting in Davos, Switzerland on January 29, 2010, Bill and Melinda Gates announced the launch of a campaign, “Decade of Vaccines,” help end child mortality in poor countries.
Currently, 79% of children in developing countries are fully vaccinated against diseases such as diphtheria, tentanus and petussis, which has already saved millions of lives. According to Johns Hopkins Bloomberg School of Public Health, if the number could be increased to 90%, an additional 7.6 million lives could be saved by 2020.
The Gates’ would like to also increase vaccination rates for other diseases, such as Haemophilus influenza type B, pneumococcal disease, and rotavirus, and to support vaccines currently being developed for malaria and tuberculosis.
The Gates’s announcement was well-received by global health leaders. Margaret Chan, director-general of the World Health Organization, called it “unprecedented,” and supported their efforts in a written statement that also called on other organizations to step up their efforts. The Gates foundation currently spends about $800 million annually on vaccine research and plans to raise that amount to $1 billion annually. It is hoped that the announcement by the Gates Foundation will encourage other organizations to fund research, development and education programs for vaccines.
Science Article Summary #4
Anderson, M. “Genome as a Commodity: In a few years, millions will have purchased their own genome.” Spectrum.ieee.org. February 2010. [Internet]. [accessed Feb 4 2010] Available from:
http://www.spectrum.ieee.org/biomedical/diagnostics/genone-as-commodity
In a few years, millions will have purchased their own genome
According to Mark Anderson, in a few years, it may be within our financial reach to purchase our entire genome in a single 1.5 gigabyte data file. He speculates that the price of the very first genome cost the US $3 billion, but that a decrease in cost over the next four years would be 1/1000 of the current price.
Apparently, purchasing one’s genome is already within the reach of some. The going price at Krome, a company in Cambridge, Massachusetts, is $68,500. A San Diego-based company, Illumina charges $48,000, and includes in the purchase price a new MacBook or iMac! According to Illumina’s president, Jay Flatley, within two years, we will be able to purchase our own genome for a mere $5000 - $10,000, and just $1000 five years down the road. Sales are modest, with just 28 human genomes sequenced in the past year, but Flatley expects these numbers to be in the thousands by 2011. Another company in Mountain View, CA, Genomics, charges $5000 per genome, but sells only in bulk amounts of 1000+.
Because of the high price, and given the fact that the medical information obtained from one’s genome is actually minimal, for now, only the wealthy can afford the cost of this luxury. Once the price comes down, it is expected that the demand will rise greatly. In some cases, those who volunteer for genome research (Personal Genome Project) may be able to obtain this valuable information at no cost. At least 15,000 people have already signed up!
http://www.spectrum.ieee.org/biomedical/diagnostics/genone-as-commodity
In a few years, millions will have purchased their own genome
According to Mark Anderson, in a few years, it may be within our financial reach to purchase our entire genome in a single 1.5 gigabyte data file. He speculates that the price of the very first genome cost the US $3 billion, but that a decrease in cost over the next four years would be 1/1000 of the current price.
Apparently, purchasing one’s genome is already within the reach of some. The going price at Krome, a company in Cambridge, Massachusetts, is $68,500. A San Diego-based company, Illumina charges $48,000, and includes in the purchase price a new MacBook or iMac! According to Illumina’s president, Jay Flatley, within two years, we will be able to purchase our own genome for a mere $5000 - $10,000, and just $1000 five years down the road. Sales are modest, with just 28 human genomes sequenced in the past year, but Flatley expects these numbers to be in the thousands by 2011. Another company in Mountain View, CA, Genomics, charges $5000 per genome, but sells only in bulk amounts of 1000+.
Because of the high price, and given the fact that the medical information obtained from one’s genome is actually minimal, for now, only the wealthy can afford the cost of this luxury. Once the price comes down, it is expected that the demand will rise greatly. In some cases, those who volunteer for genome research (Personal Genome Project) may be able to obtain this valuable information at no cost. At least 15,000 people have already signed up!
Science Article Summary #3
Biology News Net, “First discovery of the female sex hormone progesterone in a plant.” American Chemical Society. [Internet]. [accessed Feb 4 2010] Available from:
http://www.biologynews.net/archives/2010/02/04/first_discovery_of_the_female_sex_hormone_progesterone_in_a_plant.html?
First discovery of the female sex hormone progesterone in a plant
Scientists have recently had to rethink their beliefs about the differences between plants and humans due to the discovery of the female sex hormone progesterone in a plant. Progesterone is a steroid hormone produced in the ovaries of women, which is necessary for pregnancy.
Guido F. Pauli and other scientists from the American Chemical Society published their findings in their monthly trade publication, the Journal of Natural Products. According to Pauli, there is no apparent reason for the presence of progesterone in plants. He suggests that it could be a bioregulator of some sort, which is left over from billions of years of evolution. It is believed that this discovery may help scientists better understand why and how progesterone has evolved, and its relationship to living things.
Although progesterone had not previously been found in plants, a similar hormonal-type substance had been identified. Currently, researchers have had more success using nuclear magnetic resonance and mass spectroscopy to identify progesterone in plants such as walnut trees and buttercups.
http://www.biologynews.net/archives/2010/02/04/first_discovery_of_the_female_sex_hormone_progesterone_in_a_plant.html?
First discovery of the female sex hormone progesterone in a plant
Scientists have recently had to rethink their beliefs about the differences between plants and humans due to the discovery of the female sex hormone progesterone in a plant. Progesterone is a steroid hormone produced in the ovaries of women, which is necessary for pregnancy.
Guido F. Pauli and other scientists from the American Chemical Society published their findings in their monthly trade publication, the Journal of Natural Products. According to Pauli, there is no apparent reason for the presence of progesterone in plants. He suggests that it could be a bioregulator of some sort, which is left over from billions of years of evolution. It is believed that this discovery may help scientists better understand why and how progesterone has evolved, and its relationship to living things.
Although progesterone had not previously been found in plants, a similar hormonal-type substance had been identified. Currently, researchers have had more success using nuclear magnetic resonance and mass spectroscopy to identify progesterone in plants such as walnut trees and buttercups.
Science Article Summary #2
eLab – Biotechnology, “Virus-like particle vaccine protects monkeys.” Scientist Live. [Internet] 2008. [accessed Feb 4 2010] Available from:
http://www.scientistlive.com/European-Science-News/Biotechnology/Virus-like_particle_vaccine_protects_monkeys/24013/
Virus-like particle vaccine protects monkeys
Researchers at the National Institutes of Health (NIH) have developed an experimental vaccine against the chikungunya virus. This painful mosquito-borne virus, which is common in areas such as Africa and Asia, has been spreading rapidly into new areas, causing an increase in the need for an effective vaccine.
The experimental vaccine uses non-infection particles that mimic viruses. This creates an immune response without the danger of infection. These virus-like particles (VLP) have been tested on rhesus monkeys (macaques) and mice successfully when the immunization was given 15 weeks prior to the animals being exposed to the actual virus.
NIH Researchers took the experiment one step further, by inoculating macaques and mice with deficient immune systems. They found that even the immune-compromised animals were protected from lethal doses of the chikungunya virus.
Similar VLP vaccines may be developed for diseases caused by related viruses that cause fatal diseases such as encephalitis. Two other VLP vaccines, one for Hepatitis B and one for human papillomavirus, were approved by the Food and Drug Administration as of 2008. Current and future research is being conducted on an equine encephalitis virus found in the United States, as well as the o’nyong-nyong virus from Africa.
http://www.scientistlive.com/European-Science-News/Biotechnology/Virus-like_particle_vaccine_protects_monkeys/24013/
Virus-like particle vaccine protects monkeys
Researchers at the National Institutes of Health (NIH) have developed an experimental vaccine against the chikungunya virus. This painful mosquito-borne virus, which is common in areas such as Africa and Asia, has been spreading rapidly into new areas, causing an increase in the need for an effective vaccine.
The experimental vaccine uses non-infection particles that mimic viruses. This creates an immune response without the danger of infection. These virus-like particles (VLP) have been tested on rhesus monkeys (macaques) and mice successfully when the immunization was given 15 weeks prior to the animals being exposed to the actual virus.
NIH Researchers took the experiment one step further, by inoculating macaques and mice with deficient immune systems. They found that even the immune-compromised animals were protected from lethal doses of the chikungunya virus.
Similar VLP vaccines may be developed for diseases caused by related viruses that cause fatal diseases such as encephalitis. Two other VLP vaccines, one for Hepatitis B and one for human papillomavirus, were approved by the Food and Drug Administration as of 2008. Current and future research is being conducted on an equine encephalitis virus found in the United States, as well as the o’nyong-nyong virus from Africa.
Sunday, February 14, 2010
Science Article Summary #1
Hotamisligil, G. Molecular ‘firing squad’ in mice triggered by overeating destroys metabolism Harvard School of Public Health. Biology News Net [Internet] February 4, 2010.[accessed Feb 4 2010] Available from:
http://www.biologynews.net/archives/2010/02/04/molecular_firing_squad_in_mice_triggered_by_overeating_destroys_metabolism.html
Molectular 'firing squad' in mice triggered by overeating destroys metabolism.
A new study conducted by the Harvard School of Public Health, has linked a molecule which was once considered to be involved only in the body’s natural immune response to viruses, with insulin resistance in diabetes and other diseases. If researchers can figure out how the molecule is triggered, they might then be able to find ways of either treating or preventing diabetes, and other diseases including heart or liver disease, cancer and stroke.
According to the author, Gokhan Hotamisligil, when a cell containing this molecule, known as PKR, is hit with too many nutrients, it triggers an immune system response to attack the invader - in this case, food. This causes insulin resistance and metabolic dysfunction, which leads to a process described as "metaflammation." This type of inflammation is common in diseases, such as type 2 diabetes, heart disease and obesity.
Mice were used in controlled experiments where both PKR-positive and PKR-negative mice were fed high fat, high calorie diets. The PKR-positive mice developed obesity and insulin resistance, while the PKR-negative mice gained significantly less weight and did not develop insulin resistance.
Now that the PKR molecule has been identified, further studies need to be conducted in order to determine which nutrients cause adverse effects. In the future, human trials may be conducted to test potential drugs or nutrients that may help to alleviate the negative effects of PKR.
http://www.biologynews.net/archives/2010/02/04/molecular_firing_squad_in_mice_triggered_by_overeating_destroys_metabolism.html
Molectular 'firing squad' in mice triggered by overeating destroys metabolism.
A new study conducted by the Harvard School of Public Health, has linked a molecule which was once considered to be involved only in the body’s natural immune response to viruses, with insulin resistance in diabetes and other diseases. If researchers can figure out how the molecule is triggered, they might then be able to find ways of either treating or preventing diabetes, and other diseases including heart or liver disease, cancer and stroke.
According to the author, Gokhan Hotamisligil, when a cell containing this molecule, known as PKR, is hit with too many nutrients, it triggers an immune system response to attack the invader - in this case, food. This causes insulin resistance and metabolic dysfunction, which leads to a process described as "metaflammation." This type of inflammation is common in diseases, such as type 2 diabetes, heart disease and obesity.
Mice were used in controlled experiments where both PKR-positive and PKR-negative mice were fed high fat, high calorie diets. The PKR-positive mice developed obesity and insulin resistance, while the PKR-negative mice gained significantly less weight and did not develop insulin resistance.
Now that the PKR molecule has been identified, further studies need to be conducted in order to determine which nutrients cause adverse effects. In the future, human trials may be conducted to test potential drugs or nutrients that may help to alleviate the negative effects of PKR.
Subscribe to:
Posts (Atom)