靶向肠道菌群的精准膳食干预

肠道菌群的结构与功能与宿主代谢、免疫等方面的生理和病理状态有关。近年来,随着人工智能及多组学技术的发展,利用机器学习和深度学习发掘肠道菌群的潜在干预靶点,通过设计肠道菌群靶向性食品(MDF)定向调控肠道菌群组成,从而改善人体健康状态的技术逐渐成熟。本文介绍人工智能在肠道菌群干预靶点发掘中的应用,并总结肠道菌群靶向性食品的开发流程及其在营养不良、血糖管理等多方面的应用,以期为后续肠道菌群的潜在干预靶点发掘以及肠道菌群靶向性食品的开发提供新的视角。     

人体肠道菌群的试验模型的研究进展

肠道菌群与人体健康密切相关,肠内菌群可以参与人体发育、消化吸收、代谢等生理过程,因此,肠道菌群的平衡对我们的健康和疾病有着重要的影响。但是,肠道菌群数量及种类庞大,且与人体相互组成了非常复杂的生态系统,因此研究人体肠道菌群存在很多困难。文章综述了研究人体肠道菌群的体内和体外的具有代表性的试验模型方法,并概述了各模型方法的特点和问题,为完善和开发新的技术及方法提供基础与思路。     

基于高通量测序技术分析肠道菌群及其影响因素的研究进展

目前大量研究结果表明肠道菌群组成和功能与宿主健康状态密切相关。应用高通量技术能够更详细、更深层地解析肠道菌群的组成与功能。本文概述了基于高通量测序技术对宿主肠道菌群研究的结果,总结出影响肠道菌群多样性的主要因素,为宿主肠道菌群的研究提供参考。     

“抗性淀粉-肠道菌群-代谢产物”营养轴的研究进展

抗性淀粉（resistant starch,RS）在小肠内不易消化吸收,但可被大肠肠道菌群利用产生短链脂肪酸等代谢物并调节肠道菌群平衡,促进短链脂肪酸的产生及调节胆汁酸代谢。因此,本文构建“RS-肠道菌群-代谢产物”营养轴系统,概述RS调控肠道菌群介导代谢物产生的作用机制,比较菌群发酵对RS表观结构、晶体结构和分子结构产生的影响,阐述RS结构特性与肠道菌群群落结构、短链脂肪酸产量和胆汁酸排泄之间的关系,总结RS通过调节肠道菌群及肠道代谢物改善代谢性疾病的作用机制。此外,进一步展望RS-肠道菌群-胆汁酸之间的作用途径以及RS在代谢性疾病中与胆汁酸和短链脂肪酸的作用机制。     

食物成分对肠道菌群结构的影响

肠道菌群是人体重要的"微生物器官",在食物消化吸收、营养代谢、免疫功能激活、肠道屏障和机体行为调控等方面起着至关重要的作用。肠道菌群与人体之间的相互作用关系受到宿主基因型、饮食、生活环境、生活习惯、分娩方式、抗生素等因素的影响,其中饮食因素是最容易控制或改变的因素。食物成分中含有肠道菌群代谢所需的底物,并通过多种方式影响肠道菌群的结构和功能。长期相对固定的饮食结构使肠道菌群趋于稳定,当饮食结构改变时,肠道菌群也会发生相应的变化。肠道菌群结构的可变性揭示了饮食干预手段应用于肠道菌群结构平衡的调节和疾病治疗的可能性。就饮食结构、食物成分及其代谢物对肠道菌群结构的影响进行综述,旨在为未来研究饮食干预调节肠道菌群,预防疾病提供参考和新的思路。     

大豆活性组分和肠道菌群相互作用研究进展

目前食品组分与肠道菌群的相互作用及其对健康的影响已成为膳食与健康领域的研究热点。存在于动物体内的肠道菌群对大豆活性组分的分解代谢、转化吸收有着重要作用,大豆活性组分在体内肠道菌群作用下发生生物转化,导致其结构改变,从而形成新的活性成分,进而影响人体健康。同时,大豆活性组分的肠道菌群代谢产物又能够调节肠道菌群结构、保护肠黏膜屏障、维护肠道微生态平衡。本文对大豆活性组分如何在菌群作用下进行有效生物转化、肠道菌群在外源组分的扰动下如何进行菌群结构和丰度调整以及大豆组分的菌群代谢产物对人的健康影响等方面进行了综述,以期为深入研究大豆活性成分对人体健康作用的机理提供参考。     

陈化烟叶中纤维素降解菌群的分离及其特性研究

从陈化烟叶中分离到具有降解纤维素活性的菌群,分析了温度、pH和纤维素材料对菌群酶活性的影响,采用16SrDNA片段的PCR-DGGE（变形梯度凝胶电泳）技术分析菌群组成。结果显示,菌群主要由5种细菌组成。20℃时菌群纤维素酶活性很低,随着温度升高酶活性升高,在60℃时纤维素酶活性达到最高值,继续升温则酶活性下降。pH从3升高到8时,菌群纤维素酶活性不断增大,pH为8时酶活性达到最大,pH继续升高到9时则酶活性下降。菌群对烟叶、滤纸和烟梗中的纤维素都有降解作用,在以烟叶作为纤维素材料培养菌群时,纤维素酶活性明显高于滤纸和烟梗。陈化过程中微生物可能对烟叶纤维素有降解作用,从而影响烟叶的陈化效果;可以利用分离到的菌群在烟叶或烟梗发酵中降解纤维素,改善烟叶或烟梗的品质。     

几类不同食物对肠道菌群调节作用的研究进展

肠道菌群是机体的重要组成部分,肠道菌群能在一定程度上影响宿主的营养代谢和健康。肠道菌群的组成与功能受宿主生理状态、遗传、饮食习惯、年龄和环境等多重因素的影响。其中,膳食是影响肠道菌群结构和功能最为重要且较为迅速的因素。作为日常生活中常见的食物资源,杂粮、杂豆和果蔬等食物含有的膳食纤维和多酚等物质已经被证明具有调节肠道菌群的作用。肠道菌群能够发酵膳食纤维,代谢后释放维生素以及短链脂肪酸等代谢产物,并选择性地促进一些肠道有益菌的增殖,进而在一定程度上促进宿主健康。此外,大部分酚类物质也在肠道中被肠道菌群代谢分解后进一步提高酚类物质的生物利用率,从而改善宿主生理状态。本文围绕日常生活中常见的食物资源如杂粮杂豆以及水果蔬菜等对肠道菌群的调节作用进行综述,展望以肠道菌群为靶点的代谢性疾病预防与治疗或膳食干预的前景。     

肠道菌群微生态平衡与人体健康的研究进展

人体肠道微生物种类繁多且数量庞大。正常肠道菌群作为人体的天然屏障,对维持人体健康起着重要的作用。机体内外环境的变化可影响肠道菌群的结构,造成肠道菌群失衡,继而引发或加重疾病,影响人体健康。通过膳食补充益生菌和益生元,选择性地剌激和调节肠道菌群的数量和组成,保持肠道菌群的微生态平衡,是预防和治疗疾病,促进人体健康的有效措施。本文综述了国内外关于肠道菌群的组成及功能、与相关疾病及治疗的关系以及维持肠道微生态平衡的措施。     

基于高通量测序技术的蓝莓果实中细菌和真菌菌群多样性分析研究

目的 分析蓝莓中细菌和真菌菌群的组成及其多样性,探究不同蓝莓样品中微生物的暴露水平。方法 构建了蓝莓中微生物菌群的基因组文库,利用高通量测序技术分析了5种蓝莓中细菌和真菌菌群的组成及其多样性,借助微生物属水平和种水平分析比较了蓝莓中细菌和真菌菌群组成和丰度信息。结果 5种蓝莓中微生物菌群的多样性较高,但其细菌和真菌菌群组成仍存在共有特征,细菌和真菌中共有的操作分类单元数量分别为76和42。蓝莓中优势细菌主要归属于放线菌门、拟杆菌门、蓝藻菌门、厚壁菌门和变形菌门,优势真菌主要归属于子囊菌门、担子菌门和被孢霉门。结论 不同蓝莓样品中微生物菌群的组成变化较大,真菌菌群的多样性比细菌更丰富,这对蓝莓的腐烂变质、贮藏保鲜和生物防控研究具有重要意义。     

Primary care physicians' willingness to offer a new genetic test to tailor smoking treatment, according to test characteristics

Emerging pharmacogenetics research may improve clinical outcomes for common complex conditions typically treated in primary care settings. Physicians' willingness to offer genetically-tailored treatments to their patients will be critical to realizing this potential. According to recent research, it is likely that genotypes used to tailor smoking will have pleiotropic associations with other addictions and diseases, and may have different frequencies across populations. These additional features may pose an additional barrier to adoption. To assess physicians' willingness to offer a new test to individually tailor smoking treatment according to specific test characteristics, we conducted a national mailed survey of 2,000 U.S. primary care physicians (response rate: 62.3%). Physicians responded to a baseline scenario describing a new test to tailor smoking treatment, and three additional scenarios describing specific test characteristics based on published research; there was random assignment to one of two survey conditions in which the test was described as a genetic or non-genetic test. Our findings indicate physicians' self-reported likelihood (0-100 scale) that they would offer a new test to tailor smoking cessation treatment ranged from 69%-78% across all scenarios. Relative to baseline scenario responses, physicians were significantly less likely to offer the test when informed that the same genotypes assessed for treatment tailoring: (1) may also identify individuals predisposed to become addicted to nicotine (p<.001), (2) differ in frequency by race (p<.004), and (3) may have associations with other conditions (e.g., alcohol and cocaine addiction, attention deficit hyperactivity disorder ADHD and Tourette Syndrome) (p<.01). Describing a new test to individually tailor smoking treatment as a "genetic" versus non-genetic test significantly reduced physicians' likelihood of offering the test across all scenarios, regardless of specific test characteristics (p<.0007). Effective education of primary care physicians will be critical to successful integration of promising new pharmacogenetic treatment strategies for smoking.     

Cost-benefit evaluation of on-farm milk progesterone testing to monitor return to cyclicity and to classify ovarian cysts.

The effect of using on-farm milk progesterone testing to monitor return to cyclicity after parturition and to classify correctly and to treat cystic cows was evaluated using modeling and simulation. The test was evaluated assuming low and high accuracies of progesterone measurement, first breeding policy of 40 d, average estrus detection rate of 55%, and an average fertility rate of 55%. Three testing schemes (starting milk progesterone testing on d 30, 40, or 50 after parturition) were compared against a control to evaluate the effect of monitoring return to cyclicity on cows' reproductive and economic performance. For this purpose, the use of the test was an economically justifiable management intervention. Starting to test on d 30 after parturition was the most effective scheme, reducing days open by 18 d, replacement rate by 2.4%, and increasing net return per cow per year by $11. Starting to test on d 50 postpartum was not economically justifiable. Accuracy of the test, within the range used in this study, was unimportant. Testing was most profitable in herds with low fertility and low efficiency of estrus detection. The use of the test to classify follicular and luteal cysts and to select the appropriate therapy was not economically justifiable because of the low proportion of cystic cows and the high variation in response to therapy.     

多纤维标准贴衬织物在丝织物耐洗色牢度试验中的应用及比较

纺织品色牢度试验方法新标准中，在贴衬织物的选用上增加了多纤维标准贴衬织物的应用。文中通过对新老两种标准贴衬织物在丝织物耐洗色牢度试验上的应用和比较，分析探讨了应用多纤维标准贴衬后对色牢度试验结果的影响。     

高新检测技术在纺织上的应用

文章主要从应用在纺织纤维鉴别上的红外光谱技术、图像处理技术及激光技术几方面阐述了现代高新检测技术,分析了实时检测与在机检测的特点.最后指出,纺织检测技术正朝着自动化、网络化、智能化、精确化的方向发展.     

浅析聚乳酸和聚对苯二甲酸丙二酯纤维的鉴别

以应用前景较好的两种新型聚酯纤维(聚乳酸纤维、聚对苯二甲酸丙二酯纤维)和普通涤纶(聚对苯二甲酸乙二酯纤维)纤维作样品,用显微镜观察法、燃烧试验法、化学溶解试验法、熔点试验法、红外吸收光谱试验法进行分析测试,最后得出上述两种新型聚酯纤维的具体鉴别.     

Application of the Stuart test to sensory evaluation data

Examples are given to illustrate the application of the Stuart test to taste-testing and other sensory evaluation or market research applications. Convenient formulae for a generalised Stuart test, a mean scores test and a linear trend test are given. These statistical tests allow a quite thorough analysis of consumer sensory data and give an objective assessment of whether market segmentation or other nonlinear effects exist.     

缓解体力疲劳保健酒的研制

以红景天、西洋参、刺五加、枸杞子、茯苓、山药6味天然中药为主要原料,以35％vol白酒为酒基,采用冷浸、勾兑陈化等工艺制作保健酒。经急性口毒性试验、3项遗传毒性试验和30d喂养试验,表明该保健酒无毒;经小鼠负重游泳试验,表明其具有缓解身体疲劳的保健功能。     

Examining Methods to Test Factor Patterns for Concordance

To test whether the individual factor patterns of panelists and the panel factor pattern agreed, five grades of tea of the same type, ranging from low to high quality were studied. When a likelihood-ratio (LR) test and cluster analysis (CA) were applied to the 55-term correlation matrices of the seven individual panelists, according to the LR test only two of the matrices were homogeneous, but the CA test grouped all the matrices into the same cluster. The study demonstrated that the correlation matrices of the individual panelists or factor patterns themselves should be examined for agreement among panelists when factor analysis is used.     

无铬钝化剂在镀锌钢丝上的应用

采用适用于水平式连续高速电镀锌的无铬钝化剂处理镀锌钢丝,给出工艺流程和工艺参数。暴露大气加速腐蚀试验和中性盐雾试验测试表明:(1)大气腐蚀试验中,钝化后的镀锌钢丝30 h未出现腐蚀现象;(2)盐雾检测试验,未钝化镀锌钢丝8 h出现点状腐蚀现象,钝化后的镀锌钢丝23 h未出现点状腐蚀现象。无铬钝化剂处理的镀锌钢丝满足了用户对外观色泽、防腐及环保的要求。     

On a Rank Sum Test Due to Kramer

Kramer proposed two tests based on the ranked preferences of panelists. The first examines whether a predetermined treatment is superior to some other treatments. Since this test does not take into account the rank sums of the other treatments, the test is not appropriate for making this comparison. The second test examines whether there is any significant difference among the treatments. Since this test does not use the required two-tailed probabilities, it is also not appropriate for making its intended comparison. In addition, even the one-tailed probabilities are incorrect as given in the published tables.