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Mickey Tsai

Parkinson's disease sufferer Sheila Roy can write for the first time in 15 years thanks... - 0 views

www.dailymail.co.uk/...s-thanks-new-gene-therapy.html

gene therapy disease

shared by Mickey Tsai on 15 Apr 12 - No Cached
  • one of only 15 people worldwide to undergo the radical treatment, which involves inserting corrective genes into the brain
  • The genes provide the coded instructions for proteins needed to make dopamine, a brain chemical essential for proper control of movement.
  • Lack of dopamine leads to the symptoms of tremor, stiffness and poor balance associated with Parkinson’s.
  • ...3 more annotations...
  • Mrs Roy is taking part in an early-stage study of the ProSavin therapy
  • Following her treatment Sheila Roy has been able to carry out tasks like writing, something she has been unable to do for 15 years
  • Gene therapies hold great promise for people with Parkinson’s in the future, as they could mean an end to the daily regime of drugs that most people with the condition currently face.
  • Mickey Tsai on 15 Apr 12
     
    A woman with Parkinson's was able to write for the first time in 15 years because of gene therapy. Parkinson's includes symptoms such as tremors, loss of balance which makes it impossible to do even simple tasks. Doctors injected a modified virus carrying the genes to the motor centre of her brain which provide coded instructions for proteins needed to make dopamine. Lack of dopamine leads of the symptoms associated with Parkinson's. This is part of the ProSavin therapy developed by Oxford BioMedica. Gene therapies hold a lot of hope for people with Parkinson's that could end the daily routine of drugs that most of them go through.
wasin kusakabe

Athletic frogs have faster-changing genomes - 0 views

www.sciencedaily.com/...120412182332.htm

DNA Genomes Athletic Frogs

shared by wasin kusakabe on 14 Apr 12 - No Cached
    • wasin kusakabe
      wasin kusakabe on 14 Apr 12
       
      Physical activities can change the DNA sequence which can be passed on to later generations. However this has only been tested on frogs and may not apply to mammals like us.
  • athletic frogs tended to have faster-changing genomes.
  • Stretches of DNA accumulate changes over time
  • ...3 more annotations...
  • Physically fit frogs have faster-changing genomes
  • During exercise, the circulatory system provides blood and oxygen to the tissues that are needed most
  • When physical activity has stopped, the rush of blood and oxygen when circulation is restored to those tissues produces a burst of free radicals that can cause wear and tear on DNA, eventually causing genetic changes that -- if they affect the DNA of cells that make eggs or sperm -- can be passed to future generations.
wasin kusakabe

Direct transfer of plant genes from chloroplasts into the cell nucleus: Gene function p... - 0 views

www.sciencedaily.com/...120413121916.htm

Genes Chloroplasts Cell Nucleus DNA

shared by wasin kusakabe on 14 Apr 12 - No Cached
  • Chloroplasts, the plant cell's green solar power generators, were once living beings in their own right.
  • This changed about one billion years ago, when they were swallowed up but not digested by larger cells.
  • either direct transport in the form of DNA fragments from the chloroplasts to the nucleus or transport in the form of mRNA, which is then transcribed back into DNA.
  • ...5 more annotations...
  • Genes consist of several modules, separated by non-coding DNA regions (introns).
  • It was found that the transfer takes place without the involvement of RNA and that the DNA apparently jumps directly from the cell's chloroplasts into its nucleus.
  • t is thought that the introns even help the splicing enzymes by folding themselves into stable RNA structures, thus directing the enzymes to the right locations.
  • Since the introns obstruct protein synthesis, they need to be removed from the mRNA, a procedure described as splicing.
    • wasin kusakabe
      wasin kusakabe on 14 Apr 12
       
      The Chloroplasts was an different entity before they were swallowed up by larger cells to corporate with each other.
  • wasin kusakabe on 14 Apr 12
     
    The differences between the genes in the chloroplasts and the genes in the nucleus being researched.
Pop karnchanapimonkul

Dieting During Pregnancy Increases Risk Of Obesity And Diabetes For Offspring - 0 views

www.medicalnewstoday.com/...243627.php

dieting obesity diabetes epigenics offspring

shared by Pop karnchanapimonkul on 14 Apr 12 - No Cached
  • babies of mothers who diet around the time of conception and in early pregnancy, may have an increased risk of obesity and type 2 diabetes throughout their lives. This study provides exciting insights into how behavior can lead to epigenetic changes in offspring related to obesity and disease.
  • dieting around the time a baby is conceived may increase the chance of the child becoming obese later in life
  • changes in the genes that control food intake and glucose levels that may lead to obesity and diabetes.
  • ...1 more annotation...
  • epigenetic changes with alterations in the structure of the DNA and its associated proteins, histones, which affects the way that genes can behave in later life.
  • Pop karnchanapimonkul on 14 Apr 12
     
    Article about how dieting during pregnancy cause offsprings to have a change in genes.
Mickey Tsai

Niceness a combination of genetics and environment, the Neurogenics of Niceness study f... - 0 views

www.heraldsun.com.au/...story-fn7x8me2-1226324345541

genetics environment research

shared by Mickey Tsai on 14 Apr 12 - No Cached
  • BEING a nice person could come down to having a good set of genes
  • "kind" behaviour of more than 700 individuals was partly linked to receptor genes for oxytocin and vasopressin.
  • uch of the hormone you have, it's how responsive your brain is to the hormo
  • ...2 more annotations...
  • It's not about how much of the hormone you have, it's how responsive your brain is to the hormones
  • "(Niceness) is a combination of genetics and your environment."
  • Mickey Tsai on 14 Apr 12
     
    A study shows that genetics could play a role in determining "niceness". The kind behavior is found to be linked to receptor genes for oxytopic and vasopressin. People that are more responsive to it are more inclined to donate money, pay taxes, give blood, report crime etc. It isn't about how much of the hormone you have but how responsive you are to it. Of course genetics isnt the only factor, if you are surrounded by nice people it is likely that it would rub off on you.
Paige Prescott

Genes Are No Crystal Ball For Disease Risk - Science News - 0 views

www.sciencenews.org/..._crystal_ball_for_disease_risk

genes disease

shared by Paige Prescott on 14 Apr 12 - No Cached
  • For all but four diseases, the genetic data would fail to determine who is likely to contract the condition in most cases,
  • genetics are only part of the story when it comes to determining health. Lifestyle, environment and random chance play a bigger role than genes, or work with genes, to cause or protect against disease.
  • Paige Prescott on 14 Apr 12
     
    Looking at twin data, researchers found that genetics alone could not account for the risk of disease.
Paige Prescott

Old Cancer Drugs Offer New Tricks - Science News - 0 views

www.sciencenews.org/..._cancer_drugs_offer_new_tricks

cancer epigenetics

shared by Paige Prescott on 14 Apr 12 - No Cached
  • Drugs that alter some chemical tags on DNA make cancer cells behave more like normal cells
  • And the drugs seem to make cancer cells more susceptible to chemotherapy and attacks from the immune system.
  • drugs called azacitidine and decitabine, when used in low doses, change gene activity in leukemia and breast cancer cells in the lab. If DNA is a cell’s hard drive, then chemical tags attached to the DNA or DNA-packaging proteins called histones serve as software packages to tell the hard drive how to function. This type of chemical programming is called epigenetics.
Nitchakan Chaiprukmalakan

How a single gene mutation leads to uncontrolled obesity - 0 views

www.sciencedaily.com/...120318143904.htm

shared by Nitchakan Chaiprukmalakan on 13 Apr 12 - No Cached
  • Researchers at Georgetown University Medical Center have revealed how a mutation in a single gene is responsible for the inability of neurons to effectively pass along appetite suppressing signals from the body to the right place in the brain.
  • The research team specifically found that a mutation in the brain-derived neurotrophic factor (Bdnf) gene in mice does not allow brain neurons to effectively pass leptin and insulin chemical signals through the brain. In humans, these hormones, which are released in the body after a person eats, are designed to "tell" the body to stop eating. But if the signals fail to reach correct locations in the hypothalamus, the area in the brain that signals satiety, eating continues.
  • He has found that the gene produces a growth factor that controls communication between neurons.
  • ...5 more annotations...
  • The Bdnf gene generates one short transcript and one long transcript. He discovered that when the long-form Bdnf transcript is absent, the growth factor BDNF is only synthesized in the cell body of a neuron but not in its dendrites. The neuron then produces too many immature synapses, resulting in deficits in learning and memory in mice. Xu also found that the mice with the same Bdnf mutation grew to be severely obese
  • large-scale genome-wide association studies showed Bdnf gene variants are, in fact, linked to obesity.
  • both leptin and insulin stimulate synthesis of BDNF in neuronal dendrites in order to move their chemical message from one neuron to another through synapses. The intent is to keep the leptin and insulin chemical signals moving along the neuronal highway to the correct brain locations, where the hormones will turn on a program that suppresses appetite.
  • "If there is a problem with the Bdnf gene, neurons can't talk to each other, and the leptin and insulin signals are ineffective, and appetite is not modified
  • One possible strategy would be to produce additional long-form Bdnf transcript using adeno-associated virus-based gene therapy, Xu says. But although this kind of gene therapy has proven to be safe, it is difficult to deliver across the brain blood barrier,
Mickey Tsai

Autism gender bias clue found - Health - CBC News - 0 views

www.cbc.ca/...autism-males.html

autism gender gene DNA

shared by Mickey Tsai on 13 Apr 12 - No Cached
  • four times more common among males than females.
  • rare family with four generations in which males carrying the glitch were affected but females were not.
  • When male fetuses are missing one copy of the gene, it throws off their developmental process enough to lead to autism but female biology differs enough that it doesn't matter.
  • ...2 more annotations...
  • now that doctors know that the SHANK 1 gene is involved and it can be tested for, they'll know to follow affected males very closely and offer treatments early on.
  • lved and it can be tested for, they'll know to follow affected males very c
  • Mickey Tsai on 13 Apr 12
     
    Scientists have long wondered why autism is much more common among males than females. When males miss one copy of a gene it messes up the development process enough to cause autism but female biology differs enough to make it not matter. Now that scientists have identified that the SHANK 1 gene is involved they can test for it and could offer treatments early.
Nitchakan Chaiprukmalakan

New study: Tracking proteins that repair DNA - 0 views

scitechstory.com/...cking-proteins-that-repair-dna

shared by Nitchakan Chaiprukmalakan on 13 Apr 12 - No Cached
  • DNA damage could be caused by many things including toxins, radiation, or a failure in molecular chemistry. If it happens in one cell, the damage may do nothing, or at worse cause the cell to die. If damage occurs in a reproductive cell (a zygote) it can be an inherited mutation; the consequences of which can go on for generations
  • The DNA repair workers are (so far as we know) protein molecules.
  • Under microscopic observations it was seen that the UvrA protein randomly jumps from one DNA molecule to the next, staying about 7 seconds before moving on. However, when UvrA formed a complex with two UvrB molecules (UvrAB), the search became more sophisticated and slower. The complex would slide along the DNA strand for as long as 40 seconds before moving to another molecule. Sometimes it was observed that the UvrAB motion would ‘pause,’ apparently checking for structural abnormalities that might indicate DNA damage.
  • ...1 more annotation...
  • It’s assumed the protein complex is analyzing, but the mechanism of analysis is unknown. It’s also unknown if the UvrAB complex (or similar complex) actually does the repair, or if it signals for some other protein complex(es) to make the repair.
Pop karnchanapimonkul

Genetic adaptation of fat metabolism key to development of human brain - 0 views

www.sciencedaily.com/...120412133056.htm

adaptation fat metabolism brain human gene

shared by Pop karnchanapimonkul on 13 Apr 12 - No Cached
  • 300,000 years ago humans adapted genetically to be able to produce larger amounts of Omega-3 and Omega-6 fatty acids. This adaptation may have been crucial to the development of the unique brain capacity in modern humans.
  • higher risk of developing disorders like cardiovascular disease.
  • investigated the genes for the two key enzymes that are needed to produce Omega-3 and Omega-6 fatty acids from vegetable oils.
  • ...7 more annotations...
  • genetic adaptation for high production of Omega-3 and Omega-6 fatty acids is found only in humans
  • 300 000 years ago in the evolutionary line that led to modern humans
  • important factor for human survival in environments with limited dietary access to fatty acids
  • In today’s life situation, with a surplus of nourishment, this genetic adaptation contributes instead to a greater risk of developing disorders like cardiovascular disease
  • first study to show a genetic adaptation of human fat metabolism
  • thrifty gene
  • adaptation that contributed to enhanced survival in an earlier stage of human development, but in a life situation with an excess of food instead constitutes a risk factor for lifestyle diseases
  • Pop karnchanapimonkul on 13 Apr 12
     
    This article explains how earlier genetic adaptations that help our survival is now harming us.
Pop karnchanapimonkul

The Ballooning Brain: Defective Genes May Explain Uncontrolled Brain Growth in Autism: ... - 0 views

www.scientificamerican.com/article.cfm

brain genes autism

shared by Pop karnchanapimonkul on 13 Apr 12 - No Cached
  • linked atypical gene activity to excessive growth in the autistic brain
  • autistic brain sprouts an excess of neurons and continues to balloon during the first five years of life, as all those extra neurons grow larger and form connections.
  • start to lose neural connections, faster than typical brains
  • ...11 more annotations...
  • 67 percent more neurons in their prefrontal cortex (PFC) than typical children
  • executive functions"—high-level thinking, such as planning ahead, inhibiting impulses and directing attention.
  • In brain tissue from both autistic children and autistic adults, genes coding for proteins that identify and repair mistakes in DNA were expressed at unusually low levels. Additionally, all autistic brains demonstrated unusual activity levels for genes that determine when neurons grow and die and how newborn neurons migrate during early development
  • Some genes involved in immune responses, cell-to-cell communication and tissue repair, however, were expressed at unusual levels in adult autistic brains, but not in autistic children's brains
  • Errors accumulate.
  • autistic child develops in the womb, something—an inherited mutation or an environmental factor like a virus, toxin or hormone—muffles the expression of genes coding for proteins that usually fix mistakes in sequences of DNA
  • The genetic systems controlling the growth of new neurons go haywire, and brain cells divide much more frequently than usual, accounting for the excess neurons found in the PFC of autistic children.
  • autistic brain grow physically larger and form more connections than in a typical child's brain.
  • immune system reacts against the brain's overzealous growth,
  • Not all researchers, however, accept
  • If scientists definitively link autism to a characteristic sequence of changes in gene expression and unusual neural growth, then it becomes possible to target and reverse any one of the thousands of steps in that sequence.
  • Pop karnchanapimonkul on 13 Apr 12
     
    Article about how genetic expression may be the cause for autism.
Pop karnchanapimonkul

Sight Seen: Gene Therapy Restores Vision in Both Eyes: Scientific American - 0 views

www.scientificamerican.com/article.cfm

gene therapy vision disease enzyme

shared by Pop karnchanapimonkul on 13 Apr 12 - No Cached
  • gene therapy to treat blindness in 12 adults and children with Leber's congenital amaurosis (LCA), a rare inherited eye disease that destroys vision by killing photoreceptors—light-sensitive cells in the retina at the back of the eye.
  • genetic mutations in retinal cells. One mutated gene that causes the disorder is named RPE65. An enzyme encoded by RPE65 helps break down a derivative of vitamin A called retinol into a substance that photoreceptors need to detect light and send signals to the brain.
  • injected a harmless virus carrying normal copies of RPE65
  • ...8 more annotations...
  • subsequently began producing the enzyme
  • proved so much they no longer met the criteria for legal blindness
  • injected the functional genes into the previously untreated eye
  • improved as soon as two weeks after the operation: They could navigate an obstacle course, even in dim light, avoiding objects that had tripped them up before, as well as recognize people's faces and read large signs
  • brains were much more responsive to optical input as well.
  • second round of gene therapy further strengthened the brain's response to the initially treated eye as well as the newly treated one
  • that neuroplasticity plays a role
  • visual cortex responding to the newly flowing channel of information from the second eye bolster activity in areas of the visual cortex responding to the initially treated eye.
  • Pop karnchanapimonkul on 13 Apr 12
     
    Article about how the enzyme produced from gene therapy is used to cure blindness in an eye genetic disease.
Nitchakan Chaiprukmalakan

Hoogsteen base pairs: An alternate structure in DNA - 0 views

scitechstory.com/...-an-alternate-structure-in-dna

shared by Nitchakan Chaiprukmalakan on 13 Apr 12 - No Cached
  • This discovery, made by a team of researchers from the University of Michigan (USA) and the University of California, Irvine (USA) and published in the journal Nature January 26, 2011 [Transient Hoogsteen base pairs in canonical duplex DNA] involves a new capability of nuclear magnetic resonance (NMR) machines and something most people have never heard of (including me): Hoogsteen base pairs.
  • It was discovered by the biologist Karst Hoogsteen in 1963. In effect, the Hoogsteen base pair is a ‘normal’ Watson-Crick base pair (usually A-T) flipped-over like an upside-down step on a ladder.
  • It changes the geometry and allows for truly exotic formations such as a triple helix or even quadruplex structures.
  • ...4 more annotations...
  • Hoogsteen base pairs were known to exist primarily in RNA and had been observed in DNA only when there was damage to the DNA structure, or something else like a protein or drug was bound to it.
  • In RNA the Hoogsteen base pairs have been studied fairly extensively. They are considered an “excited state” and are useful to observe unusual protein binding. In DNA the Hoogsteen base pairing, which by the way has two forms, normal and reverse, was considered an anomaly.
  • It was discovered that normal DNA undergoes these shifts about 1% of the time and they last only milliseconds.
  • “Together, these data suggest that there are multiple layers of information stored in the genetic code.” Because critical interactions between DNA and proteins are thought to be directed by both the sequence of bases and the flexing of the DNA molecule, these excited states represent a whole new level of information contained in the genetic code.
Nitchakan Chaiprukmalakan

Biotechdaily - Low MicroRNA Activity Characterizes Inflamed Lung Tissues - 0 views

www.biotechdaily.com/...zes_inflamed_lung_tissues.html

shared by Nitchakan Chaiprukmalakan on 13 Apr 12 - No Cached
  • A recent study examined the interaction between a specific microRNA (miRNA) and the activity of the inflammatory cytokine interleukin 13 (IL-13).
  • In the current study, investigators at the Cincinnati Children's Hospital Medical Center (Ohio, USA) examined the effect that stimulation of IL-13 activity has on microRNAs, particularly miR-375
  • They reported in the March 28, 2012, online edition of the journal Mucosal Immunology that IL-13 induced changes in epithelial gene and protein expression including the consistent downregulation of miR-375 in IL-13 stimulated human esophageal squamous and bronchial epithelial cells.
  • ...3 more annotations...
  • Analysis of miR-375 levels in a human disease characterized by IL-13 overproduction - the allergic disorder eosinophilic esophagitis (EE) - revealed downregulation of miR-375 in EE patient samples compared with control patients. Low levels of miR-375 expression levels indicated disease activity.
  • “MiR-375 is proof of principle that microRNAs are involved in fine-tuning IL-13-mediated responses, which opens up a set of new possibilities for novel therapeutic targets for treatment of allergic disease.”
  • “The identification of a microRNA that regulates IL-13-induced changes and inflammatory pathways is a significant advancement for the understanding and future treatment of allergic disease,
Nitchakan Chaiprukmalakan

Proteins and quantum transition: Instant shape-shifting - 0 views

scitechstory.com/...nsition-instant-shape-shifting

shared by Nitchakan Chaiprukmalakan on 13 Apr 12 - No Cached
  • The genetic code in DNA provides the template to manufacture protein into all the cells of an organism.
  • Proteins are made by stringing together amino acids. For general purposes there are twenty amino acids in protein and they can be put together in endless combinations, some in short chains (yeast averages 466 amino acids), some long chains (titins have nearly 27,000 amino acids) and everything in-between. The pattern of amino acids determines much of the functionality of the protein.
  • Proteins are three-dimensional puzzle pieces. They are generally very complicated in shape. Even a small protein of only 100 amino acids can theoretically have 10^100 (ten to the hundredth power) different configurations.
  • ...7 more annotations...
  • most protein reconfigurations occur in nanoseconds
  • In research on proteins, it was assumed (given their chemical composition) proteins would uniformly fold as they cool down and unfold as they heat up. (Think of a balloon expanding and shrinking with the temperature of the air inside.) The experiments didn’t bear this out; the rate of folding or unfolding according to temperature change was unequal (asymmetric) and uneven (nonlinear).
  • In recent biochemistry a great deal of work is done with ‘tagging’ or ‘marking’ molecules with fluorescent and phosphorescent materials. It’s well known that fluorescence and phosphorescence are phenomena closely related to protein folding and they can only be understood in terms of quantum transition between molecules.
  • With a quantum transition, the protein could change configuration by ‘jumping’ – skipping all the transition steps – to the final configuration. They call this quantum folding and they developed a mathematical model that shows how the folding, which is virtually instantaneous, would react to change in temperature.
  • Their quantum transition model matched the folding curves for 15 different proteins and also provides an explanation for the different rates of folding and unfolding among these proteins.
  • Luo and Lu’s paper is short, a mere 16 pdf pages, and the model is unpretentious mathematically. (Luo has several other related papers on arXiv.) It comes from unknown researchers in an unknown corner of the academic world, and it’s published on the open-source arXiv system. The lack of pedigree means that it will take more time than usual for scientists around the world to learn of it, examine it, and possibly test it.
    • Nitchakan Chaiprukmalakan
      Nitchakan Chaiprukmalakan on 13 Apr 12
       
      This is not accepted as a true fact yet and has to be proven.
Mickey Tsai

Study finds gene variants behind childhood obesity risk - USATODAY.com - 0 views

www.usatoday.com/...1

gene childhood obesity

shared by Mickey Tsai on 13 Apr 12 - No Cached
  • Scientists have discovered two gene variants that appear to play a critical role in the development of common childhood obesity
  • Obesity is the result of a complex interplay among biological, behavioral, cultural, environmental and economic factors
  • a highly heritable condition,
  • ...2 more annotations...
  • a third of kids are obese or overweigh
  • gene research may provide insight into the biological pathways that contribute to obesity
  • Mickey Tsai on 13 Apr 12
     
    Scientists have found two gene variants that are likely to cause childhood obesity. This could be useful in knowing how to treat and prevent it. Although there is a genetic component to obesity, it is not the only factor. Biological, behavioral, cultural, environmental and economic factors can all play a role in obesity.
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