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pet-chompoo sa-ngarmangkang

Artificial Liver - 1 views

biology.about.com/...aa040899.htm

shared by pet-chompoo sa-ngarmangkang on 01 Apr 12 - No Cached
  • pet-chompoo sa-ngarmangkang on 01 Apr 12
     
    Artificial Liver Dateline: 04/08/99 The Extracorporeal Liver Assist Device, or ELAD, is the first artificial liver to use cells from humans rather than from pigs. The device is used to sustain patients awaiting a liver transplant or whose own liver is not functioning and needs to recover.
nidthamsirisup

Study suggests why some animals live longer - 1 views

www.physorg.com/...2012-03-animals-longer.html

animals dna project genetics

shared by nidthamsirisup on 02 Apr 12 - No Cached
    • nidthamsirisup
      nidthamsirisup on 02 Apr 12
       
      A new method to detect proteins associated with longevity which helps further our understanding into why some animals live longer than others.
  • The study, led by Dr. Joao Pedro Magalhaes and postgraduate student, Yang Li, is the first to show evolutionary patterns in biological repair systems in long-lived animals and could, in the future, be used to help develop anti-ageing interventions by identifying proteins in long-lived species that better respond to, for example, DNA damage
  • these species have optimised pathways that repair molecular damage, compared to shorter-lived animals, such as mice
  • ...4 more annotations...
  • found a similar pattern in proteins associated with metabolism, cholesterol and pathways involved in the recycling of proteins
  • Proteins associated with the degradation of damaged proteins, a process that has been connected to ageing, were also linked with the evolution of longevity in mammals.
  • If we can identify the proteins that allow some species to live longer than others we could use this knowledge to improve human health and slow the ageing process.
  • “We developed a method to detect proteins whose molecular evolution correlates with longevity of a species. The proteins we detected changed in a particular pattern, suggesting that evolution of these proteins was not by accident, but rather by design to cope with the biological processes impacted by ageing, such as DNA damage. The results suggest that long-lived animals were able to optimise bodily repair which will help them fend off the ageing process.”
Sasicha Manupipatpong

Divergent evolution illuminated: Light shed on reasons behind genome differences betwee... - 0 views

www.sciencedaily.com/...120329124607.htm

trna dna evolution genome differences proteins biotechnology

shared by Sasicha Manupipatpong on 01 Apr 12 - No Cached
  • divergent evolution of the genomes of different groups of species
  • three large domains: Archaea, Bacteria and Eukarya
  • genomes of each group have evolved towards distinct structures that have favored their separation
  • ...15 more annotations...
  • connection between the function of enzymes and the composition of the genomes shed light on the evolution and structure of genes
  • analyzed the distribution and abundance of transfer RNA genes
  • structure of genomes was adapted to the activity of some enzymes, which differ for Bacteria and for Eukarya and are absent in Archaea
  • activity of these enzymes modifies tRNAs, allowing them to recognize up to three distinct codons
    • Sasicha Manupipatpong
      Sasicha Manupipatpong on 01 Apr 12
       
      Prior to the study, it was understood that tRNA's have a specific anti-codon sequence which would recognize a single mRNA codon with the complementary sequence. Does this mean that the tRNA also attaches to different amino acids as well? How does the tRNA differentiate between the different amino acids it is at that moment carrying and the codon it matches with on the mRNA--does it change shape according to which amino acid is attached to it?
  • activity of the bacterial and eukaryal enzymes is different, which explains why the genomes and the gene composition of bacteria, eukarya, and archaea have diverged
  • relation between genome structure and the speed of protein synthesis from its genes
  • demonstrates how organisms have evolved in a different manner to achieve better adaptations and to have optimum protein translation efficiency
  • biotechnology as the discovery of the relevance of these modifications will allow an improvement in the industrial production of proteins
  • another parameter with which to optimize the synthesis of proteins from a gene
  • human insulin is "manufactured" in bacteria and our discovery would allow this production to be increased if we take into account the activity of these enzymes
  • relevant for the study of cancer: "it is possible that these modification enzymes are over-represented in some kinds of cancer. In fact, this would be logical because cancer cells are highly efficient in producing proteins."
  • greater the abundance of a protein in a cell the higher the number of triplets found in its gene sequence that can be read by modified tRNAs
  • don't exactly know why these enzymes appear or why they are different in bacteria and in eukaryotes but it's clear that they contribute to the separation of genomes of these two groups
  • genetic code is the same
  • what has changed is the relative importance of different codons of the code
  • Sasicha Manupipatpong on 01 Apr 12
     
    A recent study uncovers the reasons for the divergent evolution of the genomes of different species. The findings provide information about tRNA modifications which may prove useful in the field of biotechnology, specifically in the industrial production of proteins
Sasicha Manupipatpong

Identical DNA codes discovered in different plant species - 2 views

www.sciencedaily.com/...120409164426.htm

plant species identical DNA sequences medicine

shared by Sasicha Manupipatpong on 16 Apr 12 - No Cached
  • found identical sequences of DNA located at completely different places on multiple plant genomes
  • Although the scientists found identical sequences between plant species, just as they did between animals, they suggested the sequences evolved differently.
  • find identical sequences in plant DNAs
  • ...9 more annotations...
  • identical sections weren't found at the same points
  • genomes of six animals (dog, chicken, human, mouse, macaque and rat)
  • six plant species (Arabidopsis, soybean, rice, cottonwood, sorghum and grape)
  • found long strings of identical code in different species of animals' DNA
  • expect to see convergent evolution, but we don't
  • Plants and animals are both complex multi-cellular organisms that have to deal with many of the same environmental conditions, like taking in air and water and dealing with weather variations, but their genomes code for solutions to these challenges in different ways
  • could help in the development of new medicines
  • used to find identical sequential patterns in an organism's entire set of proteins
  • lead to finding new targets for existing drugs or studying these drugs' side effects
  • Sasicha Manupipatpong on 16 Apr 12
     
    A computer algorithm found identical sequences of DNA in different places of various plant species' genomes. The same has been found in animals. This could prove to be beneficial in the development of new medicines (for testing drug side effects).
Kaoko Miyazaki

Long Intergenic Noncoding RNAs: New Links in Cancer Progression - 1 views

cancerres.aacrjournals.org/...3.full

research gene epigenetics RNA

shared by Kaoko Miyazaki on 16 Apr 12 - No Cached
  • Kaoko Miyazaki on 16 Apr 12
     
    The newly discovered and currently being researched lincRNAs are seen to be one of the causes of cancer. The function of lincRNAs to control gene expression by regulating the number of histones according to specific chromatin, may cause cancer when done wrong or are altered in some way. The epigenetic alterations that occur when this function is done wrong may lead to the disease and the inheritance of it. Which could be hypothesized as to why people with a history of cancer (and other diseases) within their families have higher likelihood to being diagnosed with the disease. But because lincRNA is a very recent discovery and only less than 1% of it has has been characterized in the human body, evidence of this is still being researched, tested and studied.
orasa sukmark

Shot of Young Stem Cells Makes Rapidly Aging Mice Live Much Longer and Healthier - Gate... - 1 views

www.gate2biotech.com/-2130

shot stem cells aging much mice longer gate biotech com DNA genetics disease gene RNA brain human epigenetics research Genes

shared by orasa sukmark on 16 Apr 12 - No Cached
  • animals that got the stem/progenitor cells improved their health and lived two to three times longer than expected,
  • "Our experiments showed that mice that have progeria, a disorder of premature aging, were healthier and lived longer after an injection of stem cells from young, healthy animals," Dr. Niedernhofer said. "That tells us that stem cell dysfunction is a cause of the changes we see with aging."
  • "Typically the progeria mice die at around 21 to 28 days of age, but the treated animals lived far longer -- some even lived beyond 66 days. They also were in better general health."
  • ...2 more annotations...
  • we injected stem/progenitor cells from young, healthy mice into the abdomens of 17-day-old progeria mice,
  • As the progeria mice age, they lose muscle mass in their hind limbs, hunch over, tremble, and move slowly and awkwardly. Affected mice that got a shot of stem cells just before showing the first signs of aging were more like normal mice, and they grew almost as large.
  • orasa sukmark on 16 Apr 12
     
    the experiment from the University of Pittsburgh shows that the mice can be stronger live longer after they were injected with stem cells from young healthy animals.
Sea Maskulrath

Changes in gene expression causes high BP in pregnancy - 1 views

zeenews.india.com/...igh-bp-in-pregnancy_16515.html

epigenetics DNA human

shared by Sea Maskulrath on 16 Apr 12 - No Cached
  • Washington: Researchers have discovered that changes in the gene expression of a key enzyme may contribute to high blood pressure and increase susceptibility to forming blood clots in pregnant women with preeclampsia.
  • Epigenetics refers to changes in gene expression that are mediated through mechanisms other than changes in the DNA sequence.
  • The VCU team reported that thromboxane synthase – an important inflammatory enzyme – is increased in the blood vessels of expectant mothers with preeclampsia.The thromboxane synthase gene codes for this enzyme, which is involved in several processes including cardiovascular disease and stroke. This enzyme results in the synthesis of thromboxane, which increases blood pressure and causes blood clots.
  • ...5 more annotations...
  • According to Walsh, one of the main epigenetic mechanisms is methylation of the DNA, which controls the expression of genes. The increase of
  • his enzyme in the blood vessels is related to reduced DNA methylation and the infiltration of neu
  • enzyme
  • trophils
  • trophils into the blood vessels. Neutrophils are white blood cells that normally help fight infection.
Nickyz P.

We Need More Research On Genetically Altered Salmon Says FDA Advisory Panel - 1 views

www.medicalnewstoday.com/...201862.php

shared by Nickyz P. on 16 Apr 12 - No Cached
  • A panel of experts that advises the US Food and Drug Administration (FDA) decided on Monday more research was needed before it could vote on whether to recommend approval to allow genetically modified salmon to be bred for human consumption in the US.
  • To make the genetically modified Atlantic salmon, they take the growth gene from the Pacific chinook salmon and insert it into the DNA of newly fertilized Atlantic salmon eggs. However, this of itself is not enough to keep the salmon growing all year round: to keep the growth gene permanently "switched on", the AquaBounty scientists also add a small piece of DNA from another fish called the ocean pout.
Sasicha Manupipatpong

Memory in adults impacted by versions of four genes - 2 views

www.sciencedaily.com/...120415151347.htm

genes alzheimer's hippocampus shrinking

shared by Sasicha Manupipatpong on 16 Apr 12 - No Cached
  • advanced understanding of the genetic components of Alzheimer's disease and of brain development.
  • understanding of the genetic components of Alzheimer's disease and of brain development
  • certain versions of four genes may speed shrinkage of a brain region involved in making new memories
  • ...12 more annotations...
  • hippocampus, normally shrinks with age, but if the process speeds up, it could increase vulnerability to Alzheimer's disease
  • two genes associated with intracranial volume -- the space within the skull occupied by the brain when the brain is fully developed in a person's lifespan
  • gene variants identified in the first study do not cause Alzheimer's, but they may rob the hippocampus of a kind of "reserve" against the disease
  • cause cell destruction and dramatic shrinkage of this key brain site
  • almost twice the Alzheimer's risk if he or she had these versions of the gene
  • if a person with one of these variants did get Alzheimer's, the disease would attack an already compromised hippocampus and so would lead to a more severe condition at a younger age than otherwise
  • Alzheimer's disease causes much of its damage by shrinking hippocampus volume
  • loses a greater-than-average amount of volume due to the gene variants we've identified, the hippocampus is more vulnerable to Alzheimer's
  • associations impacting intracranial volume, which is an indirect measure of the size of the brain at full development.
  • brain volume and intracranial volume are both highly heritable
  • no associations for brain volume
  • one of these genes has played a unique evolutionary role in human development, and perhaps we as a species are selecting this gene as a way of providing further advances in brain development
  • Sasicha Manupipatpong on 16 Apr 12
     
    The shrinking of the hippocampus, which occurs with age in normal people, was found to be accelerated by certain versions of four genes, which could increase susceptibility to Alzheimer's disease, which also affects the volume of the hippocampus.
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