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61.
Living cells are powered by intricate networks of chemical reactions of thousands of molecules. Understanding how living systems emerged through the assembly of chemical processes is one of the biggest challenges in science. Subject Categories: Biotechnology & Synthetic Biology, Evolution & Ecology, Metabolism

How can chemistry turn into biology? How can living cells be built from molecules? These are fundamental questions in biology and, despite much research efforts, remain unanswered. Yet, the past two decades have seen considerable advances in our knowledge of how and which (bio)physical and (bio)chemical processes could have driven the emergence of the first living cells. These achievements have led not only to a better understanding of the molecular origins of life, but also spurred significant developments in synthetic biology, biophysics and supramolecular chemistry. Although the exact events that sparked life on Earth will quite likely remain a mystery, at least partially, exploring the chemical origins of life offers clues about our primordial past and could contribute to shaping our future.
Although the exact events that sparked life on Earth will quite likely remain a mystery […] exploring the chemical origins of life offers clues about our primordial past and could contribute to shaping our future.
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The reliability of single time point measurements of the novel adipokines retinol-binding protein 4 and omentin-1 in the blood has not been evaluated in large samples yet. The present study aimed to assess the amount of biological variation of these two adipokines within individuals. The study sample comprised 207 participants (124 women and 83 men) from Potsdam (Germany) and surrounding areas, with an average age of 56.5 years (SD 4.2). Blood samples were collected from each participant twice, approximately four months apart. Using enzyme linked immunosorbent assays, the concentrations of retinol-binding protein 4 and omentin-1 were determined in EDTA plasma. As indicators of reliability, intraclass correlation coefficients (ICCs) were calculated from the repeated biomarker measurements. The ICCs for repeated retinol-binding protein 4 and omentin-1 measurements were 0.77 (95% CI 0.71, 0.82) and 0.83 (95% CI 0.78, 0.87), respectively, indicating for both adipokines excellent reliability. ICCs were stable across strata according to sex, age, BMI, and blood pressure. Thus, for epidemiological studies it seems reasonable to rely on concentrations of retinol-binding protein 4 and omentin-1 in samples from a single time point if repeated measurements are not available.  相似文献   
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Increased Level of β-Amyloid in the Brain of Bulbectomized Mice   总被引:1,自引:0,他引:1  
Six weeks after bilateral olfactory bulbectomy, a peptide with molecular weight of 4 kD was revealed in extracts of the neocortex and hippocampus from mice. Using monoclonal antibodies 4G8, this peptide was identified as beta-amyloid. Its level was significantly higher in the bulbectomized animals than in sham-operated mice. The bulbectomized mice displayed sharp impairment in spatial memory when tested in the Morris water maze. The results suggest that bulbectomy initiates in the brain a pathological process similar to human Alzheimer's disease in location, biochemistry, and behavioral manifestations.  相似文献   
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The aim of the study was to compare the effects of neurotransplantation of cultural neural stem cells (NSC) and mesenchymal stem cells (MSC) on the rat behaviour and brain state after acute hypoxia. It was shown that development of two-way avoidance defensive conditioning in a shuttle box improved in rats-recipients with NSC, but not MSC as compared to control. Both the transplants of NSC and transplants of MSC exert neuroprotective influence on the rat brain. NSC both in vitro (before transplantation) and in vivo (on day 27 after transplantation) gave rise to all neural cell types: stem/progenitor cells, precursors of neurons and glia, neurons and glial cells. MSC population in vitro and in vivo (on day 10 after transplantation) consisted of fibroblast-like cells which were eliminated by day 20 after transplantation and were surrounded by reactive glia. We suggest that effects of NSC may be connected with their good survival and potential to differentiate into neurons and with trophic influence on the brain of recipient, whereas MSC only have possible positive trophic effect at early stages after transplantation.  相似文献   
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Microbial assemblages were composed for composting hydrolysed lignin. Data on bioconversion of aromatic compounds with various types of substitution in the ring were used for this purpose. Composting of hydrolysed lignin reduced the contents of lignin, low-hydrolyzable polysaccharides, resins, and low-molecular-weight phenols and resulted in accumulation of humic acids. The resulting compost showed no phytotoxicity.  相似文献   
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Antibiotic sensitivity and other biological properties of Aeromonas and NAD-vibrios isolated from water of open waterbodies were studied comparatively. It was found that the organisms of these genera had a definite similarity with respect to antibiotic sensitivity, morphological, cultural and some antigenic properties. The differences in the antibiotic sensitivity of these organisms were not sufficient for definition of the taxonomic features.  相似文献   
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