Biology



The study was carried out by researchers at the University of Adelaide, in Australia, who wanted to investigate whether large amounts of no-calorie artificial sweeteners altered the ability of the body to control the levels of glucose in the blood.

Some of the 27 healthy volunteers who were recruited for the study were given the equivalent of 1.5 litres of diet drink a day, in the form of capsules of two different sweeteners, sucralose and acesulfame K. They took the capsules three times a day for two weeks, before meals. The others in the study were given a placebo.

Tests at the end of the two weeks showed that the body’s response to glucose was impaired. “This study supports the concept that artificial sweeteners could reduce the body’s control of blood sugar levels and highlights the potential for exaggerated post-meal glucose levels in high habitual NAS [non-caloric artificial sweeteners] users, which could predispose them to develop type 2 diabetes,” said the authors.



“Given the renewed pharmaceutical interest in psilocybin, our results may lay the foundation for its biotechnological production,” the researchers write in the study published this month in the journal Angewandte Chemie (it’s German).

This time around, mapping the factory required sequencing the genomes of two magic mushroom species, Psilocybe cubensis and Psilocybe cyanescens. Then, the researchers found exactly which genes produce the required enzymes and spliced them into E. coli bacteria. Using those enzymes, they were able to rebuild the factory and create their own psilocybin. Hell yeah.

Other scientists thought this was a praiseworthy advance, reports Chemical and Engineering News. “The new work lays the foundation for developing a fermentation process for production of this powerful psychedelic fungal drug, which has a fascinating history and pharmacology,” University of Minnesota, Twin Cities medicinal chemist Courtney Aldrich told them.



Elephant foot vs. Human foot



At the core of what keeps cells young and healthy is our DNA. Too many cycles of cell division can trigger faster aging, before division stops altogether. In another study, which was published in the journal Science Advances, researchers specifically focused on cell division and its effects on our chromosomes. Each time a cell divides, researchers founds, a compound called nuclear respiratory factor 1 (NRF1) regulates the production of a factor that controls the shortening of telomeres attached to each of our chromosomes. Exercise boosts levels of NRF1, which in turn protects telomeres from shortening.

With each period of moderate to intense exercise, telomeres are 'refreshed,' thus helping your DNA stay healthy and your cells young.







Researchers at the Rockefeller University recently discovered a rare genetic mutation that essentially causes its carriers to adopt a sleep pattern that would be more typical for a Martian, NBC News reported. Those with the mutation typically stay up later at night because they’re on a perpetual 24 and a half-hour schedule — much like a day on Mars, which lasts 24 hours and 39 minutes.

Approximately 1.2 percent of people carry the rare mutation that disrupts the circadian rhythm, or the body’s internal clock. It's one of several causes of delayed sleep phase disorder, according to the news station. The circadian rhythm however affects more than just sleep cycles — those with the mutation also have faced issues with body temperature.



The researchers determined that CRISPR had successfully corrected a gene that causes blindness, but Kellie Schaefer, a PhD student in the lab of Vinit Mahajan, MD, PhD, associate professor of ophthalmology at Stanford University, and co-author of the study, found that the genomes of two independent gene therapy recipients had sustained more than 1,500 single-nucleotide mutations and more than 100 larger deletions and insertions. None of these DNA mutations were predicted by computer algorithms that are widely used by researchers to look for off-target effects.

“Researchers who aren’t using whole genome sequencing to find off-target effects may be missing potentially important mutations,” Dr. Tsang says. “Even a single nucleotide change can have a huge impact.”

The paper is titled, “Unexpected mutations after CRISPR-Cas9 editing in vivo.” Additional authors are Kellie A. Schafer (Stanford University), Wen-Hsuan Wu (Columbia University Medical Center), and Diana G. Colgan (Iowa).




"Since the 19th century, average life expectancy has risen almost continuously thanks to improvements in public health, diet, the environment and other areas. On average, for example, U.S. babies born today can expect to live nearly until age 79 compared with an average life expectancy of only 47 for Americans born in 1900. Since the 1970s, the maximum duration of life -- the age to which the oldest people live -- has also risen. But according to the Einstein researchers, this upward arc for maximal lifespan has a ceiling -- and we've already touched it.

Using maximum-reported-age-at-death data, the Einstein researchers put the average maximum human life span at 115 years -- a calculation allowing for record-oldest individuals occasionally living longer or shorter than 115 years. (Jeanne Calment, they concluded, was a statistical outlier.) Finally, the researchers calculated 125 years as the absolute limit of human lifespan."



"For years, people have tried to create birth control for men. The World Health Organization commissioned what sounded like a promising trial, a two-hormone injection designed to lower sperm count. Initial results looked like it would be 96 percent effective in preventing pregnancy in the participants' partners. But the Stage II trial was stopped after an independent review panel found that the drug had too many side effects. The results were published last week in The Journal of Clinical Endocrinology and Metabolism.

But two committees were paying close attention to the study, and they realized that a lot of guys were dropping out because they were experiencing side effects. The most common side effect was acne, and sometimes that acne was pretty severe. Some men also developed mood swings and in some cases those mood swings got pretty bad. One man developed severe depression, and another tried to commit suicide. Because of that, they cut the study short."






The Nobel prize in medicine has been awarded to a Japanese cell biologist for discoveries on how cells break down and recycle their own components. Dysfunctional autophagy has been linked to Parkinson’s disease, type 2 diabetes, cancer and a host of age-related disorders. Intense research is underway to develop drugs that can target autophagy to treat various diseases.

“I don’t feel comfortable competing with many people, and instead I find it more enjoyable doing something nobody else is doing,” he added. “In a way, that’s what science is all about, and the joy of finding something inspires me.”

Last year, the prize was shared by three scientists for discoveries that helped doctors fight malaria and infections caused by roundworm parasites. The Chinese chemist, Tu Youyou, was recognised for her discovery of artemisinin, one of the most effective treatments for malaria. Two other researchers, Satoshi Ōmura, an expert in soil microbes at Kitasato University, and William Campbell, an Irish-born parasitologist at Drew University in New Jersey, shared the other half of the prize, for the discovery of avermectin, a treatment for roundworm parasites.



Every minute, your heart pumps about 5 liters (1.3 gallons) of blood throughout your body, and for optimal health, it's imperative your heart continues its duty without interruption for the duration of your life.

Examples of nutrients that are important for heart health include (but are not limited to) B vitamins (including folate or B9 and B12), carnitine, taurine, coenzyme Q10 (CoQ10), magnesium, vitamin K2, vitamin D and animal-based omega-3. All of these also play important roles in keeping your mitochondria working properly. Antioxidant polyphenols are also important for combatting inflammation and damage caused by free radicals.

That said, nutrients rarely work in isolation; rather, they work in synergy with other nutrients, which means supplementing with one without taking care of other deficiencies may not produce beneficial results. For example, vitamins D and K2, magnesium and calcium work as a synergistic team, and if one is missing, the others will not perform well. Your best bet is to eat a varied diet of whole foods, rich in fresh fruits, berries and vegetables. For example, recent research suggests a Mediterranean-style diet — rich in fiber and polyphenols — may be more helpful than statin drugs for heart health."



“The study showed that aducanumab was first able to remove clumps of amyloid – a toxic protein associated with Alzheimer’s – from the brain of mice and also, excitingly, in people. What is most compelling is that more amyloid was cleared when people took higher doses of the drug. No existing treatments for Alzheimer’s directly interfere with the disease process – and so a drug that actually slows the progress of the disease by clearing amyloid would be a significant step.”

“While there were hints that it might have an effect on the symptoms of the disease, we need to see the results from further, larger research trials to understand whether this is the case. These larger trials are now under way, including in the UK, and due to finish in 2020,” Dr Pickett said.

However Gordon Wilcock, emeritus professor of geratology at Oxford University, was somewhat downbeat about the findings. "We have already had previous trials of various anti-amyloid strategies, especially the monoclonal antibodies, that have failed to deliver at phase three. Nevertheless these trials are justified by the data and I hope they are successful, despite my feelings of déjà vu!”



"First, environmental changes in DNA not mediated by genes did occur: the different sublines of the plant, though genetically identical, accumulated different methylation patterns in their DNA. These environmental “mutations” occur very rapidly and some of them are inherited over several generations. Some of them could affect gene expression, too.

DMRs (differentially methylated regions) can be considered as going through recurrent cycles of forward and reverse epimutation, which is very different from what is found at the level of the genome sequence, where reverse mutations are exceedingly rare. Importantly, reversion rates directly determine the ability of any type of allele to be subject to Darwinian selection. This needs to be taken into account when considering the potential of epialleles as a factor in evolution."



"Sure, your score would be higher if you'd had kids of your own who carried more of your genes. But natural selection isn't all-or-nothing. Your nieces, nephews, and cousins are better than no genetic descendants at all.

That's kin selection, and it's the mechanism behind something called inclusive fitness theory. The idea there: Species will evolve traits for cooperation—even traits that force them to sacrifice themselves for others—if the benefit outweighs what they loose. So, you might forgo having kids of your own if, by doing that, you enable enough nieces and nephews to survive and breed. You can see already how this relates to the ant problem."




The tree’s mystery branch, called the Candidate Phyla Radiation (CPR), is huge: about a third of the genetic diversity within the entire tree—as much as that of eukaryotes and archaea combined—comes from the CPR, study coauthor Laura Hug, a former member of the Banfield lab who is now at the University of Waterloo in Canada, told The Scientist in an email. Currently, the entire group has only a single isolated representative, Banfield said. The CPR’s members share distinctive biological features. “To date it would appear that all of these organisms [within the CPR] have symbiotic lifestyles or are at least dependent on other organisms for the vast majority of their basic metabolic resources,” said Banfield.



"For the present study, Stephen Friend and colleagues analyzed existing data from 12 genetic studies worldwide (including data collected by consumer genetics company 23andMe), looking at 874 genes in 589,306 genomes. They started with more than 15,000 resilient candidates, but after a stringent weeding-out process, the researchers identified 13 adults who had mutations for eight different severe childhood genetic disorders—including cystic fibrosis, Smith Lemli-Opitz syndrome, and familial dysautonomia—yet had no reported signs of the diseases.

Two of the people found to be resilient to the genetic diseases studied had a disease-causing version of the DHCR7 gene that has been linked to Smith Lemli-Opitz syndrome. Interestingly, both had additional DHCR7 variants, including five that are known to be benign."




"Plants often have huge, complex genomes. This is sometimes because their genomes spontaneously double, so that instead of being in pairs (diploid), their chromosomes are in group of 4 or more – these are called polyploid, and they tend to have enormous genomes. The amazing thing about the loblolly pine, which is currently the largest genome sequenced, at 22.18 billion base pairs, is that it’s actually a diploid, so it’s size and complexity is nothing to do with chromosome doubling. Sequencing the genome revealed that actually, a lot of its bulk is down to repetitive bits of sequence."



"Anandamide is a neurotransmitter and endocannabinoid produced in your brain that temporarily blocks feelings of pain and depression. It's a derivative of the Sanskrit word "bliss," and a deficiency is associated with increased anxiety and stress. Anandamide is actually found in chocolate too and is thought to be one reason why eating chocolate may give you a boost in mood (chocolate also contains other chemicals that prolong the "feel-good" aspects of anandamide).

In relation to exercise, however, anandamide levels are known to increase during and following exercise. Anandamide may also be involved in increasing a protein called Brain Derived Neurotrophic Factor (BDNF). In your brain, BDNF not only preserves existing brain cells, it also activates brain stem cells to convert into new neurons and effectively makes your brain grow larger. Research published in the journal Psychoneuroendocrinology concluded:
" … [A]cute exercise represents a physiological stressor able to increase peripheral levels of anandamide and that BDNF might be a mechanism by which anandamide influences the neuroplastic and antidepressant effects of exercise."
A recent animal study similarly found that anandamide might be responsible for producing a "runner's high" in mice. According to that study:
"Exercise is rewarding, and long-distance runners have described a runner's high as a sudden pleasant feeling of euphoria, anxiolysis [anxiety relief], sedation, and analgesia [pain relief]. A popular belief has been that endogenous endorphins mediate these beneficial effects.

However, running exercise increases blood levels of both β-endorphin (an opioid) and anandamide (an endocannabinoid) … we … demonstrate that the endocannabinoid system is crucial for two main aspects of a runner's high."



"The study was a follow-up on prior research, conducted by the same researcher, that showed that certain people were more likely to develop non-alcoholic fatty liver disease (NAFLD) if they consumed higher levels of fructose-containing beverages. The new study looked at fructose-containing beverage consumption on people who already had NAFLD. In describing this, the researchers hint that they still believe high-fructose corn syrup to be associated with scarring in the liver, or fibrosis."



"If you’ve been diagnosed with high blood pressure, pay attention to episodes of vertigo, dizziness, lack of coordination, and gait disturbance. High blood pressure can lead to damage on the inner walls of the arteries. This creates plaque that can rupture and release blood clots. Other risk factors for stroke include high cholesterol, diabetes, smoking, obesity, and atrial fibrillation."

"The corresponding incidences [of transient ischemic attack (TIA, or "mini stroke")] are similar in the United States, and lower in Japan. Higher incidences were revealed in men compared with women. The incidence of TIA increased very markedly with age, regardless of race or gender. The evidence of risk factors for TIA excluding ischemic strokes is very limited. TIAs were reported to be most frequent in autumn or spring and less common in winter or spring to summer, and most frequent on Mondays. There seems to be no consensus regarding seasonal differences in TIA incidence."



"We think of the tree of life, with genetic material passing vertically from mom and dad," first author Thomas Boothby said in a statement. "But with horizontal gene transfer becoming more widely accepted and more well known, at least in certain organisms, it is beginning to change the way we think about evolution and inheritance of genetic material and the stability of genomes. So instead of thinking of the tree of life, we can think about the web of life and genetic material crossing from branch to branch. So it's exciting. We are beginning to adjust our understanding of how evolution works."




"The actual journal article in Medicinal Chemistry Communications that inspired the press release was not about smelling farts or preventing any particular disease. Instead, it discussed the development of a compound, called AP39, that in laboratory experiments delivered very small amounts of hydrogen sulfide to mitochondria, an organelle that is the powerhouse of cells. When stressed by disease, mitochondria use minute quantities of hydrogen sulfide to keep working.

“If this doesn’t happen, the cells die and lose the ability to regulate survival and control inflammation,” said co-author Professor Matt Whiteman of the University of Exeter Medical School. “Our results indicate that if stressed cells are treated with AP39, mitochondria are protected and cells stay alive,” said Whiteman.

“Hydrogen sulfide regulates vascular function, inflammatory responses, neurotransmission in the brain, many different things,” including cancer, says Dr. Csaba Szabo, a professor of anesthesiology at the University of Texas in Galveston. “If you incubate cancer cells in the laboratory with hydrogen sulfide or a compound that produces hydrogen sulfide, you can do two things. At lower concentrations, you can stimulate the cells, and at the higher concentrations, you can kill the cells,” says Szabo.



"Monisiga brevicollis‘ specialty is tyrosine kinases — a family of enzymes that function as the 'writers' of cell-level signals. Before University of California, Berkeley cell biologist Nicole King analyzed the microbe’s genome, tyrosine kinases had never before been found in a single-celled organism, much less in the abundance charted by Salk Institute for Biological Studies researcher Gerard Manning. However, the 'readers' and 'erasers' — technically known as Src Homology 2 domains and protein tyrosine phosphatases — have been found in microbes, and are believed to have existed in early residents of the primordial soup."



"They fused those "stabilized stalk" immunogens to ferritin, a naturally occurring protein that forms nanoparticles. The resulting vaccine nanoparticles, dubbed HA-SS-np and HA-SS-np', preserved the structure of the original HA stalk, they reported online in Nature Medicine Graham and colleagues immunized mice and ferrets with the compounds, in the presence of an adjuvant. Both vaccine candidates elicited antibodies against various HA subtypes, including H1, H2, H5, and H9, while the HA-SS-np compound also drew responses to H3 and H7..

In the other study, researchers used rational design methods to engineer stable "mini-HAs" that were structurally similar to naturally occurring hemagglutinin stalks but lacked the protein head, according to Ian Wilson, PhD, of the Scripps Research Institute in La Jolla, Calif., and colleagues."



"'Using mouse models, we were able to isolate and study a pure stem cell population,' said Shen. When the researchers used whole genome sequencing to study these cells during the suckling and weaning periods, they found that DNA methylation (the addition of a methyl molecule) plays a regulatory role in intestinal stem cells. In fact, the methylation of CpG islands (CGIs) turns on important genes involved in the development of these cells. In many cases, this epigenetic development depends on some of the bacteria that make up the gut microbiome."



By comparing the effect of caffeine with that of another stimulant, the researchers determined that caffeine was acting on adenosine receptors to shift each cell’s clock. The way caffeine works on cells in the body might be different than how it works on the brain. “Your liver has clocks in it. Your muscles have clocks in them,” says Wright. “We know if you jet-lag a mouse, the brain adapts really quickly. Whereas it could take time for the other tissues to catch up. In other words, jet lag isn’t just the fact that your brain is in another time zone—it’s that your liver might be in a different time zone than your brain.”



"Sitting and being sedentary were both associated with non-alcoholic fatty liver disease (NAFLD), according to new research out of South Korea. The study, published in the Journal of Hepatology, found that people who sat for 10 or more hours per day increased their risk for the disease by nine percent. Getting active seemed to do the opposite: People who were physically active -- walking at least 10,000 steps a day, for example -- were 20 percent less likely to develop NAFLD compared to those who scarcely exercised. Close to 140,000 South Korean men and women with an average age of about 40 years were analyzed in the study."



"Okinawans also appear to forfeit their imperviousness to disease when they move to mainland Japan or the United States. On the islands they eat a low-calorie diet rich in vegetables and grains. They drink tea and antioxidant-laden rice liquor called awamori and lead active, socially connected lives. They eat primarily monounsaturated and polyunsaturated fats with few high-saturated-fat animal products, apart from fish."



"People have thought that this DNA didn't do anything," Adar said. "But it turns out that proteins bind to these other DNA sequences, and this affects other nearby or far-away genes. Our analysis shows that these DNA regulatory sequences are also being repaired. So, if they're being repaired, then they're likely important. And now we can find their locations throughout the genome."



A multicenter study validating the accuracy of the new blood tests, "Development and Validation of a Biomarker for Diarrhea-Predominant Irritable Bowel Syndrome in Human Subjects," was published this week in the journal PLOS ONE. Pimentel will also present the research on Sunday, May 17th, at Digestive Disease Week 2015 in Washington, D.C.

Pimentel and fellow researchers studied nearly 3,000 people, comparing IBS patients to those diagnosed with inflammatory bowel disease, celiac disease and those with no GI disease. The blood tests identified the two antibodies associated with IBS -- anti-Cdtb and anti-vinculin -- with greater than 90 percent certainty.



"The human vomeronasal organ has epithelia that may be able to serve as a chemical sensory organ; however, the genes that encode the VNO receptors are nonfunctional pseudogenes in humans. A possible theory being studied now is that these axillary odors are being used to provide information about the immune system. Milinski and colleagues found that the artificial odors that people chose are determined in part by their major histocompatibility complexes (MHC) combination. Information about an individual’s immune system could be used as a way of "sexual selection" so that the female could obtain good genes for her offspring. Wedekind and colleagues found that both men and women prefer the axillary odors of people whose MHC is different from their own."

"Hedione (chemical name methyl dihydro-jasmonate) – derived from the Greek word “hedone”, for fun, pleasure, lust – has a pleasant fresh jasmine-magnolia scent and is used in many perfumes. It is synthesized from the organic compound methyl jasmonate which was discovered in 1957 and which is important in plants for seed germination, root growth, flowering, fruit ripening, and senescence."



"During activities that involve a lot of running, jumping and bending — such as soccer, basketball, volleyball and ballet — your child's thigh muscles (quadriceps) pull on the tendon that connects the kneecap to the shinbone. This repeated stress can cause the tendon to pull away from the shinbone a bit, resulting in the pain and swelling associated with Osgood-Schlatter disease. In some cases, your child's body may try to close that gap with new bone growth, which can result in a bony lump at that spot.

Osgood-Schlatter disease occurs during puberty's growth spurts. Age ranges differ by sex because girls experience puberty earlier than do boys. Osgood-Schlatter disease typically occurs in boys ages 13 to 14 and girls ages 11 to 12. Osgood-Schlatter disease is more common in boys, but the gender gap is narrowing as more girls become involved with sports."







"These behavioral data aren’t so surprising, but the researchers also reported some interesting neurological results. When rats were given Oreos, a protein called c-Fos was expressed strongly in an area of the brain called the nucleus accumbens, which is well known to be active in pleasure and addiction. A final oddity of the current study: the rats apparently preferred the creamy vanilla filling to the cookie itself. Said Honohan, “They would break it open and eat the middle first.” Though this isn’t likely enough to confirm that the results are applicable to humans, it does make one wonder if we’re really not so different after all."



"Compared with 21 similarly aged people, as well as 18 volunteers aged 50 through 60, SuperAgers have an unusual brain signature characterized by three main components: a thicker, larger region of the cortex, significantly fewer neurofibrillary tangles (a marker of Alzheimer’s), and a huge supply of a neuron called von Economo, which has been linked to higher social intelligence. That particular region of the cortex, called the anterior cingulate cortex, influences cognitive control, conflict resolution, and perseverance. And in SuperAgers, it contained 87 percent less tangles than recruits of the same age and 92 percent less tangles than individuals with mild cognitive impairment."



"Mortimer predicted that it could take roughly 10 to 15 years before scientists are able to use transcription factor regulatory networks to control secondary cell wall composition. According to Brady, it will be at least a few more years before transcription factors in grasses like sorghum and switchgrass are identified.

To Hazen, it is "absolutely realistic" that researchers will be able to use their research to create better biofuel feedstocks. "We're making excellent progress," he said. Funding for the study was provided by DOE's Joint BioEnergy Division."



"The Rubisco enzyme, as it snatches up the CO2 it will use to make food, has a tendency to mess up and grab oxygen instead. Grabbing the wrong gas not only slows down the enzyme, but also ruins the work already done. Plants evolved to deal with this issue by creating a form of Rubisco that's slow and inefficient, but more careful in picking the correct gas. But cyanobacteria evolved a different solution: They use those aforementioned protective carboxysome capsules to ward off oxygen, creating a tiny, CO2-rich environments for their Rubisco."



"Mice receiving dust from the dog’s house weathered the challenge with little to no allergic reaction, but the other mice developed the mouse equivalent of a runny nose and revved up immune activity in their airways, the researchers report online today in the Proceedings of the National Academy of Sciences. In the dog dust-exposed mice, there were fewer allergy-associated immune cells and those that were present produced fewer immune system molecules that tend to lead to a strong reaction."



"Joints are also covered with a capsule. A special type of liquid called synovial fluid is contained within the capsule. Synovial fluid acts as a lubricant and contains nutrients for the cartilage and bone. The synovial fluid also contains dissolved gas. When a person stretches a joint to crack his knuckles, he creates negative pressure within the capsule. That vacuum allows more dissolved gas to enter the capsule as a bubble. When the gas bubble bursts, you hear the characteristic popping sound that we all know.

Although cracking your joints will not lead to arthritis, overzealous cracking can injure the ligaments that support those joints. That usually results in mild pain, which will go away if the knuckle-cracker takes a break from his noisy hobby. In severe cases, it can weaken one's grip by loosening the tendons that attach muscle to bone."



"Based at the University of California, Berkeley, the researchers propose a brain-machine interface that makes use of thousands of sensor nodes that would be implanted within the cortex. There, they would communicate with a transceiver located on the cranium, which would deliver piezoelectric power to the sensors. A node on the head would provide battery power and computing horsepower."



“The idea to use DNA as a language to program living organisms instead of computers is the driving force behind GenoCAD,” explains Peccoud. “Using design strategies in grammatical models of DNA sequences, GenoCAD offers simple point-and-click actions to guide users through the process of designing new sequences consisting of dozens of functional blocks in literally a matter of minutes. After the design is complete, the sequence can be downloaded through GenoCAD for synthesis or further analysis.”



Anne Wojcicki, CEO and Co-Founder, 23andMe: "We are about individuals accessing, understanding, and benefiting from the human genome."

Dr. Robert Klitzman, Bioethicist, Professor of Psychology, Columbia University; Author of Am I My Genes?: "50 genetic tests for diseases with a solid cure; 2,3% of total; more than 90% are diseases not really known"



A Conversation with Maynard Olson, A Founder of the Human Genome Project
"I like to say that the finiteness of genomic information is the only constraint on the complexity of biology."

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