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11.
Fecal microbiota transplantation (FMT) has become a research focus of biomedicine and clinical medicine in recent years. The clinical response from FMT for different diseases provided evidence for microbiota-host interactions associated with various disorders, including Clostridium difficile infection, inflammatory bowel disease, diabetes mellitus, cancer, liver cirrhosis, gutbrain disease and others. To discuss the experiences of using microbes to treat human diseases from ancient China to current era should be important in moving standardized FMT forward and achieving a better future. Here, we review the changing concept of microbiota transplantation from FMT to selective microbiota transplantation, methodology development of FMT and stepup FMT strategy based on literature and state experts’ perspectives.  相似文献   
12.
A substance cryoprotective for Vibrio cholerae on the prawn shell surface was purified by ammonium sulfate precipitation and gel filtration. It was a protein of 81 kDa and called cryoprotective protein (CPP). The cryoprotective activity of this protein for V. cholerae was sensitive to heat at 100 C and trypsin treatment. In the presence of Mg ion the protein can bind to the bacterial cell surface. V. cholerae can adhere to the shell surface of the prawn. The number of adhered bacteria was reduced by treating the shell with anti-CPP serum, heat or by trypsin. The presence of Mg ion promoted the adherence. These results suggest that the CPP could serve as an adherence site for V. cholerae on the shell surface.  相似文献   
13.
In the tropics of South China, climate change induced more rainfall events in the wet season in the last decades. Moreover, there will be more frequently spring drought in the future. However, knowledge on how litter decomposition rate would respond to these seasonal precipitation changes is still limited. In the present study, we conducted a precipitation manipulation experiment in a tropical forest. First, we applied a 60% rainfall exclusion in April and May to defer the onset of wet season and added the same amount of water in October and November to mimic a deferred wet season (DW); second, we increased as much as 25% mean annual precipitation into plots in July and August to simulate a wetter wet season (WW). Five single‐species litters, with their carbon to nitrogen ratio ranged from 27 to 49, and a mixed litter were used to explore how the precipitation change treatments would affect litter decomposition rate. The interaction between precipitation changes and litter species was not significant. The DW treatment marginally accelerated litter decomposition across six litter types. Detailed analysis showed that DW increased litter decomposition rate in the periods of January to March and October to December, when soil moisture was increased by the water addition in the dry season. In contrast, WW did not significantly affect litter decomposition rate, which was consistent with the unchanged soil moisture pattern. In conclusion, the study indicated that regardless of litter types or litter quality, the projected deferred wet season would increase litter decomposition rate, whereas the wetter wet season would not affect litter decomposition rate in the tropical forests. This study improves our knowledge of how tropical forest carbon cycling in response to precipitation change.  相似文献   
14.
We have identified a novel structural class of protein serine/threonine kinase inhibitors comprised of an aminoimidazo[1,2-a]pyridine nucleus. Compounds from this family are shown to potently inhibit cyclin-dependent kinases by competing with ATP for binding to a catalytic subunit of the protein. Structure-based design approach was used to direct this chemical scaffold toward generating potent and selective CDK2 inhibitors. The discovery of this new class of ATP-site directed protein kinase inhibitors, aminoimidazo[1,2-a]pyridines, provides the basis of new medicinal chemistry tool in search for an effective treatment of cancer and other diseases that involve protein kinase signaling pathways.  相似文献   
15.
In order to investigate the differences in the chemical composition of Dendrobium officinale at different altitudes, we collected Dendrobium officinale from different altitudes in Guizhou Province, China, and firstly determined its polysaccharide content by using a sulfuric acid-phenol color development method with reference to the Chinese Pharmacopoeia, and further determined its metabolites by using widely targeted metabolomics, and explored the differences in the chemical composition of Dendrobium officinale at different altitudes using multivariate statistical analysis. We found that the polysaccharide content was higher in plants growing at 1122 m, a total of 902 secondary metabolites were detected by wildly targeted metabolomics, and amino acids and their derivatives were more highly expressed at 1122 m, while other metabolites were more highly expressed at 835 m. Furthermore, we found that the phenolic acid compound nerugein was only present in plants at 835 m, and two lipid compounds, namely Lyso PE 20 : 4 and its isomer, were only present at 1122 m. Taken together, these results may provide a basis for the selection and clinical application of D. officinale cultivated at different altitudes.  相似文献   
16.
野生火棘在贵州省的资源分布广泛,由于省内各地区气候因子的不同,导致野生火棘果实的营养性成分存在差异。为探究贵州省野生火棘果的营养性成分差异,明确影响营养成分积累的气候因子,筛选出适宜生长区域,采用硫酸-苯酚法、全自动凯氏定氮仪、索氏提取法和福林-酚比色法对火棘果粗多糖、总蛋白、总脂肪和总多酚含量进行测定,并进行差异性分析、主成分分析和聚类分析;同时结合气候因子,进行灰色关联度的相关性分析。结果显示,不同产地之间4种营养成分含量存在明显差异,可将10个不同产地火棘分成3大类;灰色关联度分析表明,相对湿度是影响贵州野生火棘果营养成分含量的主要影响因子;降低相对湿度利于火棘果中营养性成分的积累。  相似文献   
17.
As a highly representative traditional Chinese anti-tumor medicinal material, the biomass of Mylabris is collected from the wild. However, the living environments of Mylabris is differ, so Mylabris may be contaminated by heavy metal pollution depending on the environment. These environments may also affect the amount of biosynthesis of its medicinal ingredient, cantharidin, there by affecting the quality of Mylabris. In this study, we determined the heavy metal content in Mylabris from different origins by using ICP-MS, evaluated the risk posed by these heavy metals, and recommended theoretical maximum limits of heavy metals in medicinal Mylabris. The results show that the Cu content in Mylabris is substantially higher than that in Cr, As, Pb, Cd, and Hg. A quantitative risk assessment showed that Mylabris poses no noncarcinogenic risks. The results of the total carcinogenic risk value showed that origins S12 and S13 pose carcinogenic risk by Cr and As, and the rest of the origins were in the human-tolerable carcinogenic risk range. We found large differences in the cantharidin content in Mylabris from different origins. In general, the Mylabris from origins S2, S3 and S4 had a higher in vivo cantharidin content, which proved that the quality of the medicinal materials was higher here than in other production areas. Finally, we providing a reference for the quality evaluation of medicinal Mylabris materials.  相似文献   
18.
Identification of causal rare variants that are associated with complex traits poses a central challenge on genome-wide association studies. However, most current research focuses only on testing the global association whether the rare variants in a given genomic region are collectively associated with the trait. Although some recent work, e.g., the Bayesian risk index method, have tried to address this problem, it is unclear whether the causal rare variants can be consistently identified by them in the small--large- situation. We develop a new Bayesian method, the so-called Bayesian Rare Variant Detector (BRVD), to tackle this problem. The new method simultaneously addresses two issues: (i) (Global association test) Are there any of the variants associated with the disease, and (ii) (Causal variant detection) Which variants, if any, are driving the association. The BRVD ensures the causal rare variants to be consistently identified in the small--large- situation by imposing some appropriate prior distributions on the model and model specific parameters. The numerical results indicate that the BRVD is more powerful for testing the global association than the existing methods, such as the combined multivariate and collapsing test, weighted sum statistic test, RARECOVER, sequence kernel association test, and Bayesian risk index, and also more powerful for identification of causal rare variants than the Bayesian risk index method. The BRVD has also been successfully applied to the Early-Onset Myocardial Infarction (EOMI) Exome Sequence Data. It identified a few causal rare variants that have been verified in the literature.  相似文献   
19.
In the present work, a novel n-UV convertible colour-tunable emitting phosphor was obtained based on the efficient Ce3+-Tb3+ energy transfer in the Y10Al2Si3O18N4 host. By properly controlling the ratio of Ce3+/Tb3+, the colour hue of the obtained powder covered the blue and green regions, under excitation of 365 nm. The steady-state and dynamic-state luminescence measurement was performed to shed light on the related mechanism, which was justified by the electronic dipole–quadrupole dominating the related energy transfer process. Preliminary studies showed that Y10Al2Si3O18N4:Ce3+,Tb3+ can be promising as an inorganic phosphor for white LED applications.  相似文献   
20.
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