Syndicate content

Mystery Deepens—Organism’s Apparent Lack of Sex Not Related to Dessication-Based DNA Repair As Previously Thought; Organism Does Undergo Unusual Amount of Horizontal Gene Transfer; Sexual Reproduction Cannot Yet Be Ruled Out

A new study has cast doubt on leading theory for how tiny creatures have evolved for tens of millions of years - without ever having sex. Most animals reproduce sexually, a process which shuffles genes from parent to offspring. This makes natural selection more efficient and allows animals to evolve defenses against changing environmental conditions more rapidly, especially new diseases. Bdelloid rotifers however appear to be an exception to this rule: they are all female, and their offspring are clones of their mothers. Bdelloids are microscopic animals that live in freshwater and damp habitats across the world. Despite their apparent lack of sex, we know they have evolved for tens of millions of years into more than 500 species. By studying their genomes - the set of all the genes that define an animal's characteristics - researchers thought they had identified an explanation for how bdelloids had 'gotten away' with no sex for millions of years. However, a new study, published online on April 24, 2018 in PLOS Biology and led by Imperial College London researchers, reveals this mechanism may not be the main explanation for the bdelloids' success. The article is titled “Comparative Genomics of Bdelloid Rotifers: Insights from Desiccating and Nondesiccating Species.” Many species of bdelloid endure periods of drying out, called desiccation. Although they survive desiccation, the process damages their DNA, which they need to repair when rehydrated. Based on results of a previous study of the genome of a species that survives desiccation, researchers had proposed that the repair of DNA might remove some of the problems of being asexual, for example by removing harmful mutations and possibly allowing occasional recombination of genes to occur.

Dark Chocolate Has Positive Effects on Stress, Inflammation, Mood, Memory, & Immunity, New Studies Show

New research shows there might be health benefits to eating certain types of dark chocolate. Findings from two studies being presented at the Experimental Biology 2018 annual meeting in San Diego (April 21-25) show that consuming dark chocolate that has a high concentration of cacao (minimally 70% cacao, 30% organic cane sugar) has positive effects on stress levels, inflammation, mood, memory, and immunity. While it is well known that cacao is a major source of flavonoids, this is the first time the effect has been studied in human subjects to determine how it can support cognitive, endocrine, and cardiovascular health. Lee S. Berk, DrPH, Associate Dean of Research Affairs, School of Allied Health Professions and a researcher in psychoneuroimmunology and food science from Loma Linda University, served as principal investigator on both studies. "For years, we have looked at the influence of dark chocolate on neurological functions from the standpoint of sugar content - the more sugar, the happier we are," Dr. Berk said. "This is the first time that we have looked at the impact of large amounts of cacao in doses as small as a regular-sized chocolate bar in humans over short or long periods of time, and are encouraged by the findings. These studies show us that the higher the concentration of cacao, the more positive the impact on cognition, memory, mood, immunity, and other beneficial effects." The flavonoids found in cacao are extremely potent antioxidants and anti-inflammatory agents, with known mechanisms beneficial for brain and cardiovascular health.

World First--New Structure of “Twisted Knot” DNA Revealed in Living Cells; Antibody Fragment Used to Identify I-Motif DNA; May Play Role in Gene Expression

It's DNA, but not as we know it. In a world first, Australian researchers have identified a new DNA structure - called the “i-motif” - inside cells. A twisted “knot” of DNA, the i-motif has never before been directly seen inside living cells. The new findings, from the Garvan Institute of Medical Research, were published online on April 23, 2018 in Nature Chemistry. The article is titled “I-Motif DNA Structures Are Formed in the Nuclei of Human Cells.” Deep inside the cells in our body lies our DNA. The information in the DNA code - all 6 billion A, C, G, and T letters - provides precise instructions for how our bodies are built, and how they work. The iconic “double helix” shape of DNA has captured the public imagination since 1953, when James Watson and Francis Crick famously uncovered the structure of DNA. However, it's now known that short stretches of DNA can exist in other shapes, in the laboratory at least - and scientists suspect that these different shapes might play an important role in how and when the DNA code is “read.” The new shape looks entirely different from the double-stranded DNA double helix. "When most of us think of DNA, we think of the double helix," says Associate Professor Daniel Christ (Head, Antibody Therapeutics Lab, Garvan) who co-led the research. "This new research reminds us that totally different DNA structures exist - and could well be important for our cells." "The i-motif is a four-stranded 'knot' of DNA," says Associate Professor Marcel Dinger (Head, Kinghorn Centre for Clinical Genomics, Garvan), who co-led the research with Assistant Professor Christ.

Breathtaking Discovery! Larger Spleens Are Key to Deep Diving Ability of Bajau People; Genetic Mutation May Have Led to Increased Spleen Size in “Sea Nomads” of Southeast Asia

Competitive breath-hold divers have only two options to increase their time underwater - through training, they can try to boost their lung capacity or increase their red blood cell count. Over hundreds, if not thousands of years, however, a group of Southeast Asian "sea nomads" known for their deep-diving prowess has evolved a better solution: larger spleens. The spleen holds oxygenated red blood cells, so presumably an enlarged spleen (those of the sea nomads, or Bajau people, are about 50 percent larger than the spleens of unrelated, non-diving neighboring groups) injects more blood cells into the circulation and makes more oxygen available for basic body functions during prolonged dives. The physical and genetic changes that have enabled the Bajau to dive longer and deeper is yet another example of the immense variety of human adaption to extreme environments, in this case, environments with low levels of oxygen, said Dr. Rasmus Nielsen, a Professor of Integrative Biology at the University of California, Berkeley. These examples can be key to understanding human physiology and human genetics. "We can't really make experiments in humans, where we expose people to new conditions and have controlled genetic experiments in the same way we can do in fruit flies and mice," Dr. Nielsen said. "But nature has made experiments for us that tell us how humans react and adapt genetically to a whole new set of physiological conditions, so that we can explore and learn much more about the interaction between genetics and physiology." The surprise finding led researchers from the University of Copenhagen and UC Berkeley to a genetic mutation that appears to have spread throughout the population to increase spleen size. This genetic variant upregulates thyroid hormone, which in mice has been linked to larger spleen size.

To Starve Pancreatic Tumors, Researchers Seek to Block Autophagy & Other Fuel Sources

To get the extra energy they need to fuel their uncontrolled growth, cancer cells break down some of their own parts for fuel - a process known as autophagy, or "self-eating." Researchers from the University of North Carolina (UNC) Lineberger Comprehensive Cancer Center found a possible therapeutic strategy to block self-eating in one of the deadliest cancers, as well as to cut off the tumor's other energy sources. The researchers are reporting preclinical findings for a potential two-treatment strategy to block multiple mechanisms of cancer cell metabolism in pancreatic cancer at the American Association for Cancer Research (AACR) Annual Meeting in Chicago. The findings were presented on April 18, 2018. "We know that cancer cells have a greater need for energy than normal cells," said UNC Lineberger's Channing Der (photo), PhD, Sarah Graham Kenan Distinguished Professor in the UNC School of Medicine Department of Pharmacology. "They get their energy by changing normal metabolic processes to allow them to generate more energy, and one of these processes is self-eating. Basically what a cancer cell does is it does this more efficiently than a normal cell." In other studies, pancreatic cancer cells have been known to rely more heavily on autophagy, but UNC Lineberger scientists reported evidence that a type of treatment -- an ERK inhibitor -- actually increased their reliance on this. The researchers believe the compound prevents the cell from relying on other energy sources, driving it toward autophagy. "The cancer cell has many ways to achieve what it wants in terms of getting more energy," Dr. Der said. "We find that if you try to stop one, a cancer cell has the ability to compensate. I think the analogy many of us use is the 'whack-a-mole' concept where you knock one thing down, and something else pops up.

University of Pennsylvania Continues Advancements in Cancer Immunotherapy with New Perspective

(by Rachel DeRita, PhD Candidate,Thomas Jefferson University, Department of Cancer Biology). The Abramson Cancer Center at the University of Pennsylvania (UPenn) continues to make innovative advancements in the field of cancer immunotherapy in the midst of what has been called the “immune revolution” by the cancer center’s director, Robert H. Vonderheide (photo), MD, PhD. He explains that the success with the revolutionary immune system-based therapies is “bittersweet,” as many patients are either non-responsive or re-lapse after initial success. A main strategy of the current cancer immunotherapies is to block the immune system’s “off switch.” For example, when the molecule PD-1 on immune cells is bound to PD-L1 on tumor cells, the immune system deactivates and allows the cancer to hide from the immune system. Antibodies against PD-1 (pembrolizumab, brand name Keytruda) can block the deactivation caused by PD-1/PD-L1 binding, and are approved for the first-line treatment of metastatic non-small cell lung cancer with overexpression of PD-L1. Approximately 30% of patients to not respond to this treatment and another 25% exhibit further tumor progression after one year. The search for improvements to current immunotherapies has led to a new class of immunotherapy drugs known as monoclonal antibodies to a protein called CD40. CD40 is expressed by the antigen-presenting cells of the immune system, which are responsible for eliciting an anti-tumor response. When CD40 is bound by other surface markers on T-helper cells, the antigen-presenting cell (such as a B cells or dendritic cells) is activated to perform a number of functions to eventually target and kill tumor cells. By stimulating this molecule with an antibody, the anti-tumor response is strengthened. Dr.

Moss Capable of Removing Arsenic from Water Discovered in Northern Sweden

A moss capable of removing arsenic from contaminated water has been discovered by researchers from Stockholm University. And it happens quickly - in just one hour, the arsenic level is so low that the water is no longer harmful for people to drink. The study has been published in the in the June 2018 issue of Environmental Pollution. The article is titled “Phytofiltration of Arsenic by Aquatic Moss (Warnstorfia fluitans). The aquatic moss Warnstofia fluitans, which grows in northern Sweden, has the ability to quickly absorb and adsorb arsenic from water. The discovery allows for an environmentally friendly way to purify water of arsenic. One possible scenario is to grow the moss in streams and other watercourses with high levels of arsenic. In the northern part of Sweden, water from mining areas is often contaminated by arsenic. "We hope that the plant-based wetland system that we are developing will solve the arsenic problem in Sweden's northern mining areas," says Dr. Maria Greger, Associate Professor at the Department of Ecology, Environment and Plant Sciences at Stockholm University and leader of the research group. "Our experiments show that the moss has a very high capacity to remove arsenic. It takes no more than an hour to remove 80 per cent of the arsenic from a container of water. By then, the water has reached such a low level of arsenic that it is no longer harmful to people," says research assistant Arifin Sandhi, who has conducted the experiments. In 2004, the use of arsenic compounds in wood products was banned, but arsenic still reaches ground and water systems due to mining. This happens because the ground and bedrock in certain parts of Sweden naturally contain arsenic. As a result, the drinking water and water used for the irrigation of crops also contains elevated levels of arsenic.

IDA-Wisconsin Holds Annual Conference on Dyslexia

Almost 90 attendees from all over Wisconsin, and also from Illinois and Minnesota, journeyed through rough winter weather conditions to attend a conference organized by the Wisconsin Branch of the International Dyslexia Association (IDA) (http://wi.dyslexiaida.org/), and held in the Wisconsin Dells on Saturday, April 14, 2018. The theme of the conference was “Moving Literacy Forward Until Everyone Can Read.” Attendees included teachers, tutors, parents, some who are afflicted by dyslexia, and vendors who provide products to aid those with dyslexia. Conference sponsors included the Walbridge School in Madison, Wisconsin; Mount St. Joseph University; and the 2017 IDA Reading, Literacy & Learning Conference Audio Recordings. The Walbridge School (http://walbridgeschool.org/) was founded in 1984 by educators and parents in order to meet the academic, social, and emotional needs of children who learn differently. Mount St. Joseph University is a Cincinnati-based educational institute that offers a fully online reading science program (http://www.msj.edu/academics/graduate-programs/master-of-arts-teacher-ad...). Session recordings with slide decks from the IDA's Reading, Literacy & Learning Conference in November 2017 are now available for purchase at www.dyslexiaida.org. Vendors at this year’s conference included IDA-Wisconsin, Decoding Dyslexia Wisconsin, Mount St. Joseph, Silver Moon Spelling Rules, Sylvan Spirit Pqbd Jewelry, Waldbridge School, School Specialty Instruction & Intervention, and Project Success UW-Oshkosh.

Immunotherapy (Keytruda), When Combined with Chemotherapy, Doubles Survival Time of Patients with Metastatic Lung Cancer

The immunotherapy drug pembrolizumab (Keytruda), when combined with chemotherapy, doubles survival in patients with non-squamous non-small cell lung cancer (NSNSCLC) lacking genetic changes in the EGFR or ALK genes, when compared to chemotherapy alone, according to results of an international phase III clinical trial. Principal investigator Leena Gandhi, MD, PhD, Director of the Thoracic Medical Oncology Program at Perlmutter Cancer Center at New York University (NYU Langone Health and associate professor of medicine in the Division of Medical Oncology at New York University (NYU) School of Medicine, presented these findings April 16, 2018 at the American Association for Cancer Research (AACR) Annual Meeting in Chicago. The data from this study were simultaneously published online on April 16, 2018 in the New England Journal of Medicine. The open-access article is titled “Combination of Pembrolizumab & Chemotherapy Doubles Survival in Patients with Metastatic Lung Cancer.” A total of 616 patients with untreated metastatic NSNSCLC without EGFR or ALK alterations, from 118 international sites, were randomly allocated for the trial—405 patients were treated with both pembrolizumab and platinum therapy plus pemetrexed, and 202 received platinum therapy plus pemetrexed with a saline placebo. Response rates, overall survival, and progression-free survival rates were superior in the pembrolizumab and chemotherapy combination treatment group. In the press release provided here and below, see a video of Dr.

How Plants Avoid DNA Damage from UV Light--Nobel Laureate Aziz Sancar’s Lab Reveals First-Ever Repair Map of an Entire Multicellular Organism to Illuminate Inner Workings of Plant Kingdom's Highly Efficient DNA Repair System

If the ultraviolet radiation from the sun damages human DNA to cause health problems, does UV radiation also damage plant DNA? The answer is yes, but because plants can't come in from the sun or slather on sunblock, they have a super robust DNA repair kit. Today, the Unversity of North Carolina (UNC) School of Medicine lab of 2015 Nobel laureate Aziz Sancar, MD, PhD, has published an exquisite study of this powerful DNA repair system in plants, which closely resembles a repair system found in humans and other animals. The study, published online on April 17, 2018 in Nature Communications, is the first repair map of an entire multicellular organism. It revealed that the "nucleotide excision repair" system works much more efficiently in the active genes of plants as compared to humans. And this efficiency depends on the day/night cycle. The open-access Nature Comminications article is titled “Genome-Wide Excision Repair in Arabidopsis Is Coupled to Transcription and Reflects Circadian Gene Expression Patterns.” "These findings advance our understanding of DNA repair mechanisms common among all organisms and may also have practical applications," said co-corresponding author Ogun Adebali, PhD, a postdoctoral researcher in the Sancar lab. First author Onur Oztas, PhD, a postdoctoral researcher in the Sancar lab, said, "DNA damage accumulating in a plant will impair its growth and development, so boosting the excision repair system could be a good strategy for improving crop yields." Dr.

Syndicate content