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Study accurately dates coral loss at Great Barrier Reef

Study accurately dates coral loss at Great Barrier Reef

Historical and modern photographs of Stone Island taken in a) 1915 (photographer unknown); b) 1994 (photographer A. Elliot © Commonwealth of Australia GBRMPA); c) 2012 (photographer H. Markham); and Bramston Reef taken in d) c.1890 (W. Saville-Kent); e) 1994 (photographer A. Elliot © Commonwealth of Australia GBRMPA); f) 2012 (photographer T. Clark). Landscape features in the background of the images helped to locate the same sites: Gloucester Island (GI) and Cape Gloucester (CG). Credit Source: Clark et al. 2016. The timing of significant Great Barrier Reef coral loss captured by a series of historical photos has been accurately determined for the first time by a University of Queensland)-led study.

http://www.biyologlar.com/study-accurately-dates-coral-loss-at-great-barrier-reef-haber-8729

Cıvık Mantarlar Ögrendiklerini Diğer Cıvık Mantarlara Aktarabiliyorlar

Cıvık Mantarlar Ögrendiklerini Diğer Cıvık Mantarlara Aktarabiliyorlar

P. polycephalum, bir hücreli organizma, daha çok cıvık mantar olarak bilinir. Laboratuarda agarda büyütülebilir. Credit: Audrey Dussutour (CNRS)

http://www.biyologlar.com/civik-mantarlar-ogrendiklerini-diger-civik-mantarlara-aktarabiliyorlar

Monterey Körfezin’de bir asır sonra yeniden bulunan canlı

Monterey Körfezin’de bir asır sonra yeniden bulunan canlı

Bilim adamları, 1900 yılında ilk kez tarif edildiğinden beri kesin olarak görülemeyen garip ve zor bulunan bir yaratığın bulgularını doğruladılar.

http://www.biyologlar.com/monterey-korfezinde-bir-asir-sonra-yeniden-bulunan-canli

Genomda İnsan Beyni İçin Önemli Endojenik Retrovirüsler

Genomda İnsan Beyni İçin Önemli Endojenik Retrovirüsler

Brattas ve ark. ERV'lerin insan sinir öncü hücrelerinde TRIM28 ile bağlandığını bildirmiştir. Bu, gelişmekte olan insan beynindeki transkripsiyonel ağların kontrolünde ERV'ler için bir rol teşkil ederek, yakın gen ekspresyonunu etkileyen yerel heterokromatin oluşturulmasına neden olur.

http://www.biyologlar.com/genomda-insan-beyni-icin-onemli-endojenik-retrovirusler

Antibiyotik Kıyameti Ve Bilinmesi Gerekenler

Antibiyotik Kıyameti Ve Bilinmesi Gerekenler

Antibiyotiklerin direnci bizler antibiyotikleri sıklık ve hevesle kullanmadan çok önce başlamıştır. Modern bakterilerin antibiyotiklere karşı kendilerini korumak için kullandıkları genler, 30.000 yıldan uzun bir süredir Arctic permafrost'ta donmuş antik bakterilerde bulunmuştur. (Credit: Alamy)

http://www.biyologlar.com/antibiyotik-kiyameti-ve-bilinmesi-gerekenler


2. Ulusal Alg Teknolojisi Sempozyumu

2. Ulusal Alg Teknolojisi Sempozyumu

KOngre Tarihi : 24-27 Mayıs 2016 Kongre Merkezi : Euphoria Aegean Otel Seferihisar / İzmir

http://www.biyologlar.com/2-ulusal-alg-teknolojisi-sempozyumu

23. Ulusal Biyoloji Kongresi

23. Ulusal Biyoloji Kongresi

23. Ulusal Biyoloji Kongresi, 5-9 Eylül 2016 tarihlerinde sizlerin katılımıyla Gaziantep’ te düzenlenecektir.

http://www.biyologlar.com/23-ulusal-biyoloji-kongresi


3. Uluslararası Biyosidal Kongresi

3. Uluslararası Biyosidal Kongresi

Kongre Tarihi : 22-25 Kasım 2016 Kongre Merkezi : Antalya Maritim Pine Beach Hotel

http://www.biyologlar.com/3-uluslararasi-biyosidal-kongresi

II. BİYOLOJİ ÖĞRENCİ KONGRESİ <b class=red>2016</b>

II. BİYOLOJİ ÖĞRENCİ KONGRESİ 2016

Kongre Tarihi: 10-12 Mart 2016 Kongre Merkezi : Kocaeli Üniversitesi Prof. Dr. Baki Komşuoğlu Kültür ve kongre merkezi

http://www.biyologlar.com/ii-biyoloji-ogrenci-kongresi-2016

Dağıtım Deposu Kalite Uzmanı

Dağıtım Deposu Kalite Uzmanı

Genel Nitelikler•Eczacı, Kimya Mühendisi, Kimyager, Biyolog•Farmasötik Üretim ve Kalite Yönetiminde min.5 yıl GMP ve Mesleki deneyim•İyi düzeyde İngilizce yazma ve okuma becerisi tercih sebebidir•MS Office, MS Windows, SAP, MS Outlook kullanabilme İş Tanımı•Tedarik Zinciri departmanının belirlediği öncelik sırasına göre, bitmiş ürünleri (genel itibariyle import ve sekonder ambalajlama yerinde işlem görmüş ve fason firmada üretilen ürünler) serbest bırakmak ve numune alımı, arşiv numuneleri ve parti dokümanlarının arşivlenmesini organize etmek. İmport ürünlerin tüm Kalite Yönetimi Master Datalarını yönetmek ve piyasadan iade edilen ürünleri değerlendirerek iade edilen ürünlerin kullanım kararı konusunda Kalite Güvence Müdürünü ve Lokal Kalite Temsilcisini desteklemek.•Dağıtım deposunda saklanan ürünlerin uygun koşullarda saklanmasını sağlamak ve transport validasyonları ile, soğuk zincir ürünlerinin uygun koşullarda transfer edilmesini sağlamak.•Global talepler doğrultusunda, yeni/mevcut ürünlerin yeniden ambalajlama ve yeniden etiketleme gereklilikleri durumunda, ilgili ambalajlama formlarının hazırlanması ve gerekli taleplerin ilgili sistemlerde başlatılması•Verimli ekip çalışmasına odaklı, profesyonel, adil, kişileri eğiten, motive edici, ilham verici ve girişimci bir çalışma ortamı yaratmak ve Dağıtım Deposu Kalite Yetkilisi, Kalite Güvence Müdürü, Kalite Grup Müdürü, İK ve yasal gerekliliklere başvurarak kişilerin işe alınması ve geliştirilmesini desteklemek.Şehir/Ülke: İstanbul(Asya)İlan Tarihi: 05.04.2016Personel Sayısı: (Belirtilmemiştir)AYRINTILAR VE MÜRACAAT İÇİN KARİYER.NET

http://www.biyologlar.com/dagitim-deposu-kalite-uzmani

GMP Uyumluluk Uzmanı

GMP Uyumluluk Uzmanı

Genel Nitelikler•Biyolog, Eczacı, Kimya Mühendisi, Kimyager•Farmasötik Üretim ve Kalite Yönetiminde min. 3 yıl GMP ve mesleki deneyim•MS Office, MS Windows, Lotus Notes kullanabilmek•İyi düzeyde İngilizce yazma ve okuma becerisine sahip olmak İş Tanımı•©GMP kurallarına uygunluğu sağlamak için, Bayer Politika & Global SOP’lerini yerel Dökümantasyon Sistemi içine adapte etmek ve bu yerel SOP lere göre tüm personel için iş eğitim programlarını planlamak, uygulamak ve takip etmek. •Compliance Management System dökümanlarının adaptasyonunu takip etmek.•Eğitimlerin (GMP-SOP-Yeni İşe Başlayan) zamanında ve eksiksiz gerçekleşmesinisağlamak. •Standart Operasyon Prosedürleri sisteminin güncelliğini sağlamak ve bölüme ait genel SOP’leri hazırlamak. •Tüm Kalite Güvence dökümanlarının işleyişi ,takibi, dağıtımı, imha ve arşivleme aktivitelerini ©GMP kuralları doğrultusunda gerçekleştirmek.Şehir/Ülke: İstanbul(Avr.)İlan Tarihi: 15.04.2016Personel Sayısı: (Belirtilmemiştir)AYRINTILAR VE MÜRACAAT İÇİN KARİYER.NET

http://www.biyologlar.com/gmp-uyumluluk-uzmani

Shiny fish skin inspires nanoscale light reflectors

Shiny fish skin inspires nanoscale light reflectors

A nature-inspired method to model the reflection of light from the skin of silvery fish and other organisms may be possible, according to Penn State researchers. Such a technique may be applicable to developing better broadband reflectors and custom multi-spectral filters for a wide variety of applications, including advanced optical coatings for glass, laser protection, infrared imaging systems, optical communication systems and photovoltaics, according to Douglas Werner, John L. and Genevieve H. McCain Chair Professor in Electrical Engineering, Penn State. The proposed model also contributes to the understanding of the reflective layering in the skin of some organisms. The shiny skins of certain ribbonfish reflect light across a broad range of wavelengths, giving them a brilliant metallic appearance. The reflectivity is the result of stacked layers of crystalline organic compounds embedded in their skin's cytoplasm. Some organisms with metallic sheens have layers that are stacked in a regular pattern, while others, including the ribbonfish, have stacking patterns described as "chaotic" or random. The Penn State team determined that the stacking is not completely random and developed mathematical algorithms to replicate those patterns in semiconductor materials. "We are proposing a model that uses fractal geometry to describe the layering in the biological structure of silvery fish," says Jeremy Bossard, postdoctoral researcher in electrical engineering, Penn State. "While we are not trying to reproduce the structure found in nature, the same model could guide the design of devices such as broadband mirrors." Fractals have been called the "geometry of nature" because they can help describe the irregular but self-similar patterns that occur in natural objects such as branching tree limbs. The researchers use a one-dimensional fractal, known as a Cantor bar fractal, which is a line divided by spaces or gaps. Normally, Cantor fractals appear to be very regular, but when random changes are introduced to the geometry, a more complex pattern emerges. The pattern resembles the layering of reflective layers in ribbonfish skin. "There is an underlying pattern, but there is randomness built in," says Bossard, "similar to the way that living trees have an overall fractal pattern but do not grow symmetrically." The researchers then use another nature-inspired computational method called a genetic algorithm that mimics Darwinian evolution to create successive generations of fractal patterns from the parent patterns. Over approximately 100 generations, the patterns converge on the best design to meet all the target requirements. Using these fractal random Cantor bars and the genetic algorithm, the researchers were able to mathematically generate patterns targeting optical functions in the mid-infrared and near-infrared ranges, including broadband reflection. They propose that the design approach could be used to develop nanoscale stacks with customized reflective spectra. The research results are reported in the January 13, 2016 issue of the Journal of the Royal Society Interface in "Evolving random fractal Cantor superlattices for the infrared using a genetic algorithm." Lan Lin, a recent Ph.D. graduate in electrical engineering, also contributed to the work and performed materials fabrication and characterization for the project. Source: Penn State http://www.biologynews.net

http://www.biyologlar.com/shiny-fish-skin-inspires-nanoscale-light-reflectors


Mantis shrimp inspires next generation of ultra-strong materials

Mantis shrimp inspires next generation of ultra-strong materials

This is the herringbone structure of the outer layer (impact region) of the mantis shrimp dactyl club.

http://www.biyologlar.com/mantis-shrimp-inspires-next-generation-of-ultra-strong-materials

Stem cell transplant from young to old can heal stomach ulcers

Stem cell transplant from young to old can heal stomach ulcers

Bethesda, MD (June 16, 2016) -- Basic and translational research paves the way for breakthroughs that can ultimately change patient care. Three new studies from Cellular and Molecular Gastroenterology and Hepatology (CMGH) -- AGA's basic and translational open-access journal -- provide a glimpse into future treatment strategies for stomach ulcers, inflammatory bowel disease and alcoholic liver disease. Please find summaries below. To speak with the journal authors, please email media@gastro.org. Healing Stomach Ulcers Through Stem Cell Transplantation The Development of Spasmolytic Polypeptide/TFF2-Expressing Metaplasia (SPEM) During Gastric Repair Is Absent in the Aged Stomach By Amy C. Engevik, et al. Ulcers of the stomach are more common as we age due to a variety of changes, including reduced ability to heal small injuries. Engevik and colleagues show that gastric stem cells isolated from young mice can be transplanted into sites of injury within the stomachs of older mice, and that this results in accelerated repair. The ability of the transplanted young mouse cells, but not stem cells from older mice, to differentiate into a specialized cell type, termed SPEM, which is central to the healing process, appears to be a central component of this. While more work must be done, it is clear that this approach, or other means of inducing older cells to differentiate into SPEM, would be powerful in treatment of gastric injury. Rethinking the Role of the Gut Microbiome in IBD Microgeographic Proteomic Networks of the Human Colonic Mucosa and Their Association With Inflammatory Bowel Disease By Xiaoxiao Li, et al. The intestinal microbiome has been the subject of intense scientific and lay interest over the past decade, and changes have been correlated with disease states. Most of this work has, however, relied on analyses of microbes within stool, which may not be representative of microbial populations that interface directly with the intestinal lining, i.e. mucosal surface. Further, characterization of stool microbes does not allow analysis of differences that may be present in separate regions of the intestine. Li and colleagues analyzed microbial proteins at the surface of six separate sites within the colon of healthy subjects and those with Crohn's disease or ulcerative colitis. The data show that microbial populations at mucosal surfaces are related, but distinct, in separate regions of the colon. This suggests that we must change our view of the microbiome as a soup in which all components are present in equal proportions at all sites to that of a mosaic composed of networks reflecting local mucosal ecology. Such understanding is essential as efforts to manipulate the microbiome for therapeutic purposes continue. Hydrazine Shows Potential as Therapy for Acute Alcoholic Liver Disease Acrolein Is a Pathogenic Mediator of Alcoholic Liver Disease and the Scavenger Hydralazine Is Protective in Mice By Wei-Yang Chen, et al. Liver disease is caused by many disorders and toxic agents, of which alcohol is the most common. However, the underlying cellular processes that cause widespread damage, which can lead to cirrhosis, are not well defined. Chen and colleagues demonstrates that acrolein -- a byproduct of alcohol consumption that is increased with increased dietary intake of polyunsaturated fatty acids -- mediates many of the damaging effects of alcohol on the liver. Hydrazine -- an acrolein scavenger in clinical use -- protected mice from the damaging effects of alcohol, suggesting that hydralazine or similar drugs might be potential therapies in acute alcoholic liver disease. Want more basic and translational research? Review other CMGH articles in press by visiting http://cmghjournal.org/inpress. For all of the articles highlighted here, the authors have no conflicts to disclose. Source: American Gastroenterological Association http://www.biologynews.net

http://www.biyologlar.com/stem-cell-transplant-from-young-to-old-can-heal-stomach-ulcers

DNA damage by ultrashort pulses of intense laser light

DNA damage by ultrashort pulses of intense laser light

DNA damage caused by very low-energy electrons and OH-radicals formed upon irradiation of water by ultrashort pulses of very intense laser light.

http://www.biyologlar.com/dna-damage-by-ultrashort-pulses-of-intense-laser-light

Watching the luminescent gene switch

Watching the luminescent gene switch

The system consists of two newly developed programs that automatically identify the 3-D positions of target areas based on the signals from the scintillators (shown as white dots), and determine...

http://www.biyologlar.com/watching-the-luminescent-gene-switch


Breakthrough in scaling up life-changing stem cell production

Breakthrough in scaling up life-changing stem cell production

Scientists have discovered a new method of creating human stem cells which could solve the big problem of the large-scale production needed to fully realise the potential of these remarkable cells for understanding and treating disease.

http://www.biyologlar.com/breakthrough-in-scaling-up-life-changing-stem-cell-production

Four newly identified genes could improve rice

Four newly identified genes could improve rice

The GWAS results for genes that influence flowering dates. The known genes Hd1, Hd2, and Hd6 were located, together with two newly-identified genes that also affect flowering dates.

http://www.biyologlar.com/four-newly-identified-genes-could-improve-rice

Gene Drive Technology: Where is the future?

Gene Drive Technology: Where is the future?

Gene drive technologies may one day help alleviate the burden caused by diseases transmitted by mosquitoes and other animal vectors.

http://www.biyologlar.com/gene-drive-technology-where-is-the-future

Thousands on one chip: New method to study proteins

Thousands on one chip: New method to study proteins

Protein microarrays like this allow the investigation of thousands of proteins in a single experiment. Microarrays are only a few centimeters in size and host thousands of individual test spots...

http://www.biyologlar.com/thousands-on-one-chip-new-method-to-study-proteins

Quantum dots with impermeable shell: A powerful tool for nanoengineering

Quantum dots with impermeable shell: A powerful tool for nanoengineering

Images of ZnO quantum dots prepared by the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw, taken by transmission electron microscopy. False colors.

http://www.biyologlar.com/quantum-dots-with-impermeable-shell-a-powerful-tool-for-nanoengineering

In some genetic cases of microcephaly, stem cells fail to launch

In a very severe, genetic form of microcephaly, stem cells in the brain fail to divide, according to a new Columbia University Medical Center study that may provide important clues to understanding how the Zika virus affects the developing brain.

http://www.biyologlar.com/in-some-genetic-cases-of-microcephaly-stem-cells-fail-to-launch


Legions of nanorobots target cancerous tumors with precision

Legions of nanorobots target cancerous tumors with precision

The legions of nanorobotic agents are actually composed of more than 100 million flagellated bacteria

http://www.biyologlar.com/legions-of-nanorobots-target-cancerous-tumors-with-precision

Purest yet liver-like cells generated from induced pluripotent stem cells

Purest yet liver-like cells generated from induced pluripotent stem cells

This image shows induced pluripotent stem cells expressing a characteristic cell surface protein called SSEA4 (green).

http://www.biyologlar.com/purest-yet-liver-like-cells-generated-from-induced-pluripotent-stem-cells


Scientists discover protein's starring role in genome stability, and possibly cancer prevention

Scientists discover protein's starring role in genome stability, and possibly cancer prevention

If you have a soft spot for unsung heroes, you'll love a DNA repair protein called XPG. Scientists from the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) discovered that XPG plays a previously unknown and critical role helping to maintain genome stability in human cells. Their findings also raise the possibility that the protein helps prevent breast, ovarian, and other cancers associated with defective BRCA genes. The research, which is published online Jan. 28, 2016 in the journal Molecular Cell, indicates XPG is essential to our health in ways far beyond it's been given credit for. "We discovered a new function for an "old" repair protein that shows the protein is key to genome stability, and is probably important for suppressing breast and ovarian cancer," says Priscilla Cooper of Berkeley Lab's Biological Systems and Engineering Division. She conducted the research with Kelly Trego and several other Berkeley Lab researchers, and scientists from Colorado State University, Yale University, and Erasmus University Medical Center in the Netherlands. Scientists have known for years that XPG helps carry out a DNA repair process that activates when only one of DNA's two strands is damaged. The process, called nucleotide excision repair, removes DNA lesions caused by sun exposure, chemotherapy, and other sources. Now, to their surprise, the Berkeley Lab scientists discovered XPG is also instrumental in a process called homologous recombination, which repairs breaks on both DNA strands in cells that are copying their genomes to get ready to divide. Double-strand breaks are especially perilous to an organism because they can lead to genome rearrangements in a cell. The scientists learned that XPG interacts with at least five other cellular proteins, including BRCA1 and BRCA2, to carry out homologous recombination. Defects in genes that express BRCA1 and BRCA2 are known causes of breast, ovarian, pancreatic, and prostate cancer. Their new study shows that cells with reduced levels of XPG have a much higher prevalence of genome instability in the form of cell cycle defects, DNA double-strand breaks, chromosomal abnormalities, and other problems. The first hint that XPG does something in addition to nucleotide excision repair came about two decades ago when scientists learned that particular mutations in the gene that codes for XPG cause an extremely rare and devastating premature aging disorder called Cockayne syndrome. Nucleotide excision repair is not implicated in Cockayne syndrome, so scientists knew XPG must play a role in another fundamental cellular process. What that function was, however, remained a big mystery. "We've spent the past several years searching for this unknown function of XPG," says Trego. To begin their search, the Berkeley Lab scientists reduced the expression of XPG in human cells and studied what happened. These "knockdown" cells had a slew of problems associated with cell growth and cell cycle, as well as an increase in DNA double-strand breaks. Next, the scientists set out to determine whether these problems are caused by a breakdown in the DNA replication process, in which two identical copies of DNA are made from one DNA molecule. They treated the cells with a chemical that causes replicative stress, and sure enough, the cells with reduced XPG levels were much more susceptible to the chemical. This narrowed the search to homologous recombination repair, which is the most prevalent way of fixing broken replication forks. More research all but confirmed XPG's importance in homologous recombination repair: the scientists found that cells with reduced levels of XPG had a 50 percent loss in the repair process. In a final step, the scientists mapped out mechanistically how XPG helps drive homologous recombination repair. Their results suggest that XPG swoops in during the initial stage of the process to clear chromatin of BRCA1, a protein that helps initiate repair. This step is thought to serve as a "reset button" for homologous recombination repair to allow the process to proceed. Almost nothing was known about this important step until now. The scientists also found that XPG interacts with BRCA2 during a later stage in the process to load a protein called RAD51 onto DNA in need of repair. RAD51 is the "recombinase" protein that is essential for carrying out homologous recombination repair, but it needs help loading onto damaged DNA to perform its function. "Until now, these direct interactions between XPG and BRCA1, BRCA2, and RAD51 during homologous recombination repair were unknown," says Cooper. "These interactions, and the greatly increased genome instability that occurs in XPG's absence, strongly suggest the protein is another important tumor-suppressor protein." Source: DOE/Lawrence Berkeley National Laboratory http://www.biologynews.net

http://www.biyologlar.com/scientists-discover-proteins-starring-role-in-genome-stability-and-possibly-cancer-prevention


T cells use 'handshakes' to sort friends from foes

T cells use 'handshakes' to sort friends from foes

T cells, the security guards of the immune system, use a kind of mechanical "handshake" to test whether a cell they encounter is a friend or foe, a new study finds.

http://www.biyologlar.com/t-cells-use-handshakes-to-sort-friends-from-foes

First gene linked to temperature sex switch

First gene linked to temperature sex switch

The sex of many reptile species is set by temperature. New research reported in the journal GENETICS identifies the first gene associated with temperature-dependent sex determination in any reptile.

http://www.biyologlar.com/first-gene-linked-to-temperature-sex-switch

May repairs full of mistakes develop into cancer?

May repairs full of mistakes develop into cancer?

These are DNA double-strand breaks, introduced by ionizing radiation or other mechanisms, are repaired rapidly and precisely in normal cells (right pathway). In contrast, compromised Tel1 activation with inefficient end...

http://www.biyologlar.com/may-repairs-full-of-mistakes-develop-into-cancer

Scientists find that cancer can arise from changes in the proteins that package DNA

Scientists find that cancer can arise from changes in the proteins that package DNA

In some cancers, including chondroblastoma and a rare form of childhood sarcoma, a mutation in histone H3 reduces global levels of methylation (dark areas) in tumor cells

http://www.biyologlar.com/scientists-find-that-cancer-can-arise-from-changes-in-the-proteins-that-package-dna

Scientists capture the elusive structure of essential digestive enzyme

Scientists capture the elusive structure of essential digestive enzyme

Stylized graphic of SEC-SAXS data (with cyan cross-section showing the elution profile and magenta cross-section showing scattering profile) and the structure of the activated phenylalanine hydroxylase

http://www.biyologlar.com/scientists-capture-the-elusive-structure-of-essential-digestive-enzyme

Heme, a poisonous nutrient, tracked by 'Green Lantern' sensor

Heme, a poisonous nutrient, tracked by 'Green Lantern' sensor

Tailor-made ratiometric sensors make baker's yeast cells light up green, as Georgia Tech scientists use it to track the movements of the essential toxin heme

http://www.biyologlar.com/heme-a-poisonous-nutrient-tracked-by-green-lantern-sensor

Genetic code of red blood cells discovered

Genetic code of red blood cells discovered

Eight days. That's how long it takes for skin cells to reprogram into red blood cells. Researchers at Lund University in Sweden, together with colleagues at Center of Regenerative Medicine in Barcelona, have successfully identified the four genetic keys that unlock the genetic code of skin cells and reprogram them to start producing red blood cells instead. "We have performed this experiment on mice, and the preliminary results indicate that it is also possible to reprogram skin cells from humans into red blood cells. One possible application for this technique is to make personalised red blood cells for blood transfusions, but this is still far from becoming a clinical reality", says Johan Flygare, manager of the research group and in charge of the study. Every individual has a unique genetic code, which is a complete instruction manual describing exactly how all the cells in the body are formed. This instruction manual is stored in the form of a specific DNA sequence in the cell nucleus. All human cells -- brain, muscle, fat, bone and skin cells -- have the exact same code. The thing that distinguishes the cells is which chapter of the manual the cells are able to read. The research group in Lund wanted to find out how the cells open the chapter that contains instructions on how to produce red blood cells. The skin cells on which the study was based had access to the instruction manual, but how were the researchers able to get them to open the chapter describing red blood cells? With the help of a retrovirus, they introduced different combinations of over 60 genes into the skin cells' genome, until one day they had successfully converted the skin cells into red blood cells. The study is published in the scientific journal Cell Reports. "This is the first time anyone has ever succeeded in transforming skin cells into red blood cells, which is incredibly exciting", says Sandra Capellera, doctoral student and lead author of the study. The study shows that out of 20,000 genes, only four are necessary to reprogram skin cells to start producing red blood cells. Also, all four are necessary in order for it to work. "It's a bit like a treasure chest where you have to turn four separate keys simultaneously in order for the chest to open", explains Sandra. The discovery is significant from several aspects. Partly from a biological point of view -- understanding how red blood cells are produced and which genetic instructions they require - but also from a therapeutic point of view, as it creates an opportunity to produce red blood cells from the skin cells of a patient. There is currently a lack of blood donors for, for instance, patients with anaemic diseases. Johan Flygare explains: "An ageing population means more blood transfusions in the future. There will also be an increasing amount of people coming from other countries with rare blood types, which means that we will not always have blood to offer them". Red blood cells are the most common cells in the human body, and are necessary in order to transport oxygen and carbon dioxide. Millions of people worldwide suffer from anaemia -- a condition in which the patient has an insufficient amount of red blood cells. Patients with chronic anaemia are among the most problematic cases. They receive regular blood transfusions from different donors, which can eventually lead to the patient developing a reaction to the new blood. They simply become allergic to the donor's blood. Finding a feasible way to make blood from an individual's own skin cells would bring relief to this group of patients. However, further studies on how the generated blood performs in living organisms are needed. Source: Lund University http://www.biologynews.net/archives/2016/06/02/genetic_code_of_red_blood_cells_discovered.html

http://www.biyologlar.com/genetic-code-of-red-blood-cells-discovered

Biological 'clock' discovered in sea turtle shells

Biological 'clock' discovered in sea turtle shells

Radiocarbon dating of atomic bomb fallout found in sea turtle shells can be used to reliably estimate the ages, growth rates and reproductive maturity of sea turtle populations in the wild, a new study led by Duke University and NOAA researchers finds. The technique provides more accurate estimates than other methods scientists currently use and may help shed new light on factors influencing the decline and lack of recovery of some endangered sea turtles populations. "The most basic questions of sea turtle life history are also the most elusive," said Kyle Van Houtan, fisheries research ecologist at NOAA's Pacific Islands Fisheries Science Center and adjunct associate professor at Duke's Nicholas School of the Environment. Van Houtan and his colleagues analyzed hard tissue from the shells of 36 deceased hawksbill sea turtles collected since the 1950s. The turtles either died naturally or were harvested for their decorative shells as part of the global tortoiseshell trade. The researchers worked with federal agencies, law enforcement and museum archives to obtain the specimens. The scientists were able to estimate each turtle's approximate age by comparing the bomb-testing radiocarbon accumulated in its shell to background rates of bomb-testing radiocarbon deposited in Hawaii's corals. Levels of carbon-14 increased rapidly in the biosphere from the mid-1950s to about 1970 as a result of Cold War-era nuclear tests but have dropped at predictable rates since then, allowing scientists to determine the age of an organism based on its carbon-14 content. Van Houtan and his team were able to estimate median growth rates and ages of sexual maturity in the collected specimens by comparing their radiocarbon measurements to those of other wild and captive hawksbill populations whose growth rates were known. This is the first time carbon-14 dating of shell tissue has been used to estimate age, growth and maturity in sea turtles. Previously, scientists employed other, less precise methods such as using turtle length as a proxy for age, or analyzing the incomplete growth layers in hollow bone tissue. The researchers published their peer-reviewed research Jan. 6, 2016, in the Proceedings of Royal Society B. Aside from giving scientists a more reliable tool for estimating turtle growth and maturity, Van Houtan believes the new technique sheds light on why some populations -- including Hawaiian hawksbills, the smallest sea turtle population on Earth -- aren't rebounding as quickly as expected despite years of concerted conservation. "Our analysis finds that hawksbills in the Hawaii population deposit eight growth lines annually, which suggests that females begin breeding at 29 years -- significantly later than any other hawksbill population in the world. This may explain why they haven't yet rebounded," Van Houtan said. The bomb radiocarbon tests also indicate another red flag, he said. "They appear to have been omnivores as recently as the 1980s. Now, they appear to be primarily herbivores. Such a dramatic decline in their food supply could delay growth and maturity, and may reflect ecosystem changes that are quite ominous in the long term for hawksbill populations in Hawaii," he said. Although the new research focused primarily on Hawaiian hawksbills, bomb radiocarbon dating could be used to study other hawksbill populations, or populations from other sea turtle species, worldwide. Source: Duke University http://www.biologynews.net

http://www.biyologlar.com/biological-clock-discovered-in-sea-turtle-shells

An unexpected origin for calming immune cells in the gut

An unexpected origin for calming immune cells in the gut

Biologically speaking, we carry the outside world within us. The food we ingest each day and the trillions of microbes that inhabit our guts pose a constant risk of infection--and all that separates us from these foreign entities is a delicate boundary made of a single layer of cells. The immune cells that swarm about this threshold must exercise a precise balancing act. They must be vigilant, yet also tolerant of harmless substances so that they don't cause harmful overreactions. New research at The Rockefeller University described in Science explains how a specific set of immune cells in the gut originate to help maintain this equilibrium. Inflammation is a key element of the body's nonspecific response to a threat, but if activated inappropriately, it can damage tissue, or lead to allergies and autoimmune disease. Throughout the body, white blood cells called regulatory T cells, or T regs, are tasked with calming the inflammatory response. "But T regs are strangely absent in the thin lining of the gut--a place where one would expect to see lots of them, since immune responses need to be tightly controlled," says co-corresponding author Bernardo Reis, a research associate in Daniel Mucida's Laboratory of Mucosal Immunity. "Instead another class of potentially anti-inflammatory T cells, called intraepithelial (or IEL) CD4 cells, populates this boundary. We found an unexpected connection between these two types of calming cells," Reis adds. Their experiments revealed that some CD4 IELs arise from T regs that have traveled into the lining, or epithelium, of the gut. The team, which included first author Tomohisa Sujino, co-authors Mariya London and David P. Hoytema van Konijnenburg from Mucida's lab, began by tracking the T regs within the epithelium and the tissue below in the gut of living mice. When they counted these immune cells by location they found a telling discrepancy: Many T regs migrated into the epithelium from the body, but never returned. To find out what was happening to these immune cells, they labeled the T regs and watched them over five weeks. In that time, they found that about half of the T regs stopped expressing the protein Foxp3, an important marker of regulatory T cells. Of these, a portion converted to CD4 IELs. This is the first time T-regs have been shown to switch their identity and turn into another cell type within a living organism; until now, they have been thought to be stable. The microbes living on the other side of the gut epithelium appear to contribute to this conversion. When the researchers treated mice with antibiotics, the T-regs stopped switching their identity. "This research reveals how the gut has evolved its own specialized pathway for maintaining the delicate balance between an efficient immune response and the need for tolerance," says Mucida. Source: Rockefeller University http://www.biologynews.net/

http://www.biyologlar.com/an-unexpected-origin-for-calming-immune-cells-in-the-gut

Research reveals trend in bird-shape evolution on islands

Research reveals trend in bird-shape evolution on islands

In groundbreaking new work, Natalie Wright, a postdoctoral fellow at the University of Montana, has discovered a predictable trend in the evolution of bird shape.

http://www.biyologlar.com/research-reveals-trend-in-bird-shape-evolution-on-islands

UMD researchers discover a way that animals keep their cells identical

UMD researchers discover a way that animals keep their cells identical

Roundworms (Caenorhabditis elegans) with a disabled eri-1 gene can lose their ability to control repetitive DNA. In the absence of eri-1, even two age-matched siblings can look dramatically different. Cancers arise in skin, muscle, liver or other types of tissue when one cell becomes different from its neighbors. Although biologists have learned a lot about how tissues form during development, very little is known about how two cells of the same tissue stay identical for an animal's entire lifetime. A University of Maryland research team is the first to discover that a regulatory protein named ERI-1 helps ensure that all cells in a tissue remain identical to one another. The work involved collaboration between developmental biologists and computer scientists, with the latter contributing their expertise with machine learning analysis. The finding could bring biologists one step closer to understanding some cancers and other age-related diseases. The study, which is the first of its kind conducted in a whole animal (the roundworm Caenorhabditis elegans) instead of cultured cells, appears in the August 1, 2016 issue of the Journal of Cell Biology. The researchers' approach reveals one important mechanism that animals use to maintain uniform patterns of gene expression. The team's use of machine learning software proved essential for quickly and clearly identifying complex patterns in the data. "Cells can look the same and behave the same, but how? The liver is full of liver cells and doesn't have any heart cells, for example. There's so much that needs to happen to maintain a tissue," said Antony Jose, an assistant professor in the UMD Department of Cell Biology and Molecular Genetics and senior author on the study. "It's a fundamental question that's been hiding in plain sight. We've now proposed an answer that could help advance our understanding of age-related diseases." The results suggest that long sections of repetitive DNA can be read differently from cell to cell. The researchers found that, in healthy tissues, ERI-1 normalizes these differences by ensuring that each cell expresses their genes at the same levels. When the researchers turned off the gene that produces ERI-1 in C. elegans, an abnormal patchwork of gene expression appeared in the worms' intestines. "To understand these processes, we needed to measure single-cell differences in a whole animal," Jose said. "We had to know which cell was related to which others and simultaneously measure various properties in all cells within a tissue. Technically, achieving this is very difficult. But you can't adequately answer these questions outside the context of the whole animal." To achieve this complex analysis, Jose and his colleagues formed an unexpected collaboration. Lead author Hai Le (B.S. '13, biological science), an undergraduate researcher in Jose's lab who is now a student at the Johns Hopkins University School of Medicine, presented a poster at UMD's Bioscience Day conference in 2012. Future collaborator Michael Bloodgood, an associate research scientist at UMD's Center for Advanced Study of Language, stopped by to discuss Le's work. The two researchers quickly recognized the potential for machine learning to help facilitate Le and Jose's analysis. "Linguists use machine learning to compare blocks of text to identify nouns and verbs, analyze sentence structures and determine average word length, for example," Jose said. "Hai and Michael recognized that we could use the same technique to analyze gene expression in intestinal cells." Machine learning software can reveal complex patterns that the human eye cannot see. As the name implies, the software can be taught to look for specific patterns and can also "learn" from experience, becoming more efficient with each subsequent analysis. Using this approach enabled the researchers to quickly make objective comparisons that would have been all but impossible using other methods. The researchers chose C. elegans because it is a simple organism that can easily be studied at the level of a single cell while it is still alive. Jose notes that their technique is broadly applicable, and could be modified to work with other genes and different tissues as well. If others adopt the team's whole-animal methodology, Jose believes it could signal a shift in the way cell biologists approach their experimental design. "The effect of cancer drugs is often examined in cultured cells. Our work suggests that studies on cells outside an animal could miss many things. For example, cultured cells can show differences in gene expression that are eliminated in a whole animal," Jose said. "I believe our results could lead to some shifts in thinking about how to imitate a whole animal in cell culture conditions." Source: University of Maryland http://www.biologynews.net

http://www.biyologlar.com/umd-researchers-discover-a-way-that-animals-keep-their-cells-identical

TSRI researchers find 'lead actors' in immune cell development

TSRI researchers find 'lead actors' in immune cell development

Authors of the new paper include (left to right) Changchun Xiao, David Nemazee, Alicia Gonzalez Martin and Maoyi Lai of The Scripps Research Institute

http://www.biyologlar.com/tsri-researchers-find-lead-actors-in-immune-cell-development

A molecular alarm clock awakens resting ovules

A molecular alarm clock awakens resting ovules

Ovarian follicle of fruit fly, with chromosomes stained in green and dKDM5 protein stained in red.

http://www.biyologlar.com/a-molecular-alarm-clock-awakens-resting-ovules

NIH-funded study reveals how differences in male and female brains emerge

NIH-funded study reveals how differences in male and female brains emerge

Nematode worms may not be from Mars or Venus, but they do have sex-specific circuits in their brains that cause the males and females to act differently.

http://www.biyologlar.com/nih-funded-study-reveals-how-differences-in-male-and-female-brains-emerge




 
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