甘露寡糖对异育银鲫生长性能、免疫及HSP70基因表达的影响

为探讨甘露寡糖(MOS)对异育银鲫生长、免疫、肠道组织结构及抗病力的影响,试验选取360尾异育银鲫[初均重(16.19±0.03)g],随机分成5组、每组3个重复,在日粮中添加不同浓度甘露寡糖(0、60、120、240、480 mg/kg),连续投喂80d,并于第80天时进行嗜水气单胞菌感染,测定异育银鲫生长、免疫、肠道结构等指标及异育银鲫抗嗜水气单胞菌感染的能力。试验结果表明,无论投喂50d,还是80d,甘露寡糖对鱼体的生长指标(特定生长率、增重率、蛋白质效率、饵料系数)均没有显著影响(P>0.05);投喂50d,与对照组比,甘露寡糖能显著提高血清球蛋白浓度(P<0.05);投喂80d后,与对照组比,240、480 mg/kg甘露寡糖组能显著提高碱性磷酸酶活性,甘露寡糖组能显著提高血清球蛋白浓度(P<0.05),480 mg/kg甘露寡糖组能显著提高血清总抗氧化能力,120、240 mg/kg甘露寡糖组能显著提高肠褶皱襞长(P<0.05),对皱襞间质宽、黏膜下层宽没有显著影响(P>0.05),肌层宽随着MOS的添加有增加趋势(P>0.05);嗜水气单胞菌感染后,与对照组比,240、480 mg/kg甘露寡糖组成活率提高了22.6%,免疫保护率达45.4%。日粮中添加甘露寡糖组对鱼体肝脏HSP70基因表达没有显著影响(P>0.05)。因此,添加240、480 mg/kg甘露寡糖能提高鱼体的免疫能力,增强鱼体抗病原菌感染能力。     

甘露寡糖对纯培养和共培养的乳酸杆菌体外生长的影响

三株(S、L和M)猪源乳酸杆菌以甘露寡糖(mannan-oligosaccharide, MOS)为碳源体外纯培养或与猪源致病性大肠杆菌共培养, 研究MOS对乳酸杆菌的选择性生长作用。结果表明, 纯培养时, 三株菌MOS组的OD值和乳酸浓度均高于对照, pH均低于对照, 但菌株之间存在差异。共培养时, 乳酸杆菌和大肠杆菌都可利用MOS进行生长, 但乳酸杆菌的生长强于大肠杆菌, 产生较多的乳酸、显著降低pH(P＜0.05) , 这种促生长作用在最初的12 h较明显。     

壳寡糖对杂交黄颡鱼“黄优1号”(黄颡鱼♀×瓦氏黄颡鱼♂)生长性能与免疫机能的影响

为研究饲料中添加不同剂量壳寡糖(COS)对杂交黄颡鱼“黄优1号”(Tachysurus fulvidraco ♀× Tachysurus vachelli ♂)生长性能、特异及非特异性免疫机能的影响, 试验分4组, 壳寡糖有效剂量分别以0、40、80和120 mg/kg添加到饲料中, 为期56d。结果显示: 120 mg/kg组特定生长率(SGR)显著高于对照组, 饲料系数(FCR)显著低于对照组(P<0.05); 随壳寡糖剂量增大, 蛋白质效率(PER)变化趋势与FCR相反。同时, 各剂量壳寡糖均能显著提高白细胞吞噬指数(PI, P<0.05); 淋巴细胞转化率(LTR)随壳寡糖剂量增大而显著升高(P<0.05), 剂量达80 mg/kg后保持稳定(P>0.05); 高剂量试验组(80和120 mg/kg)溶菌酶活力和IgM水平显著高于低剂量组(40 mg/kg)和对照组 (P<0.05)。研究结果表明: 在试验条件下, 饲料中添加壳寡糖能显著提升杂交黄颡鱼“黄优1号”生长速度, 降低饲料系数, 促进白细胞吞噬功能及淋巴细胞转化, 并能提高体液免疫水平, 建议有效剂量为80—120 mg/kg。     

海洋活性物质壳寡糖对尿酸钠致痛风性关节炎的影响

目的:研究海洋活性物质壳寡糖对尿酸钠致痛风性关节炎的影响,并初步探讨其可能的作用机制.方法:取健康雄性SD大鼠48只随机分为:生理盐水对照组,模型组,秋水仙碱组,壳寡糖(低、中、高剂量)组.连续灌胃给药7天,于第4天制备大鼠急性痛风性关节炎动物模型,并于0,1 h,2h,4h,6h,12h,24h,48h,72h分别测量造模关节同一部位周径,以致炎前后的差值作为痛风性关节炎的肿胀程度.72h测周长后麻醉取血,进行白细胞计数和垂清IL-1β检测.结果:(1)造模前各实验组大鼠关节周径无明显差异(P>0.05),造模后各组大鼠关节周径均有增加,且在12h后达高峰,其中以模型组最为明显,壳寡糖各剂量组及秋水仙碱组关节周径均有不同程度下降;24h后随着治疗时间的延长肿胀逐渐恢复,壳寡糖各剂量组及秋水仙碱组关节肿胀度12h、24h低于模型组(P<0.01,P<0.05),生理盐水组无明显肿胀高峰.(2)壳寡糖高、中剂量组可升高模型大鼠血白细胞(P<0.01).(3)壳寡糖高、中剂量组可降低模型大鼠血清IL-1β趋势(P<0.01).结论:尿酸钠踝关节腔注射可以成功制备大鼠急性痛风性关节炎模型,海洋活性物质壳寡糖可以缓解急性痛风性关节炎发作,且高、中剂量组疗效稳定.     

甘露寡糖对断奶仔猪肠道主要菌群的影响

选择健康的 35日龄断奶仔猪 4 8头 ,随机分为两组 ,每组 3圈 ,每圈 8头。一组为含 0 .5 %甘露寡糠 +基础日粮 ,另一组为基础日粮。试验开始第 7天 ,每组各随机选 6头仔猪 ,麻醉后剖腹取肠道内容物以测定盲肠和结肠大肠杆菌、乳酸杆菌及双歧杆菌浓度和 p H。试验结果表明 ,与对照组相比 ,甘露寡糖可以显著降低盲肠、结肠大肠杆菌浓度 (P<0 .0 5 ) ;同时显著提高盲肠乳酸杆菌和双歧杆菌浓度 (P<0 .0 5 ) ,但对结肠乳酸杆菌和双歧杆菌数影响不显著 (P>0 .0 5 )     

壳寡糖对环江香猪生化参数及肠道菌群组成的影响

为了探讨壳寡糖(COS)用作环江香猪饲料添加剂的可行性,试验选用21日龄断奶的环江香猪12头,随机分为2组,每组6头,分别饲喂添加0.5%COS的基础日粮和添加抗生素的基础日粮,试验期为14 d。试验结束时采集仔猪血液,肝素抗凝,离心分离血浆,测定生化参数;处死后取回肠和盲肠内容物,用荧光定量PCR测定其中双歧杆菌、乳酸杆菌、链球菌、大肠杆菌和总细菌的数量。结果表明,与对照组相比,壳寡糖组仔猪碱性磷酸酶活性显著增加(P<0.05),血氨和尿素氮含量有降低趋势(P>0.05);壳寡糖组回肠乳酸杆菌数量显著增加、链球菌数量显著降低(P<0.05),盲肠双歧杆菌和乳酸杆菌数量显著增加、大肠杆菌和链球菌数量显著降低(P<0.05)。上述结果提示,壳寡糖可在一定程度上改善环江香猪蛋白质代谢和肠道菌群平衡,从而增强其肠道健康。     

牛蒡寡糖诱导黄瓜抗炭疽病的研究

本研究证明了牛蒡寡糖能显著诱导黄瓜对炭疽病的抗性。黄瓜幼苗经0.05%的牛蒡寡糖处理后,以病斑数计算的对炭疽病诱抗效果为50.01%,以病斑面积计算的诱抗效果为56.83%。而用牛蒡寡糖诱导后,四种与植物抗性有关的酶的活性随诱导时间的延长呈现出不同的动态变化。β-1,3-葡聚糖酶在诱导后第4天的活性最高,超氧化物岐化酶(SOD)在诱导后第3天活性最高,多酚氧化酶(PPO)的活性从诱导后第4天开始持续升高,而过氧化氢酶(CAT)的活性在诱导后则有所降低,与同期对照相比最大降低幅度为29%。     

壳寡糖对ARF兔肾的保护作用及其血液流变学的影响

目的探讨壳寡糖(Chitosanoligosaccharide,COS)对急性肾功能衰竭(ARF)兔肾的保护作用及其血液流变学的变化。方法选用健康雄性日本大耳白兔24只,随机均分为4组:ARF+NS组、ARF+COS组、NS+NS组和NS+COS组。观察兔灌胃48h后,血清尿素(BUN)和肌酐(Cre)水平的变化,肾皮质匀浆丙二醛(MDA)水平和超氧化物歧化酶(SOD)活性的变化,以及血液流变学指标的变化。结果与ARF+NS组比较,ARF+COS组血清BUN和Cre明显降低(P<0.01);肾皮质匀浆MDA水平降低,SOD活性升高(P<0.05);Hct无明显变化,其他血液流变学指标均明显降低(P<0.01)。结论壳寡糖可通过抗氧化作用、改善血液流变学的变化,有效改善肾功能,起到保护肾脏的作用,为COS的临床利用提供又一理论依据。     

艾曲波帕联合硫唑嘌呤治疗RITP的疗效及其作用机制研究

目的:探究艾曲波帕联合硫唑嘌呤治疗难治性原发免疫性血小板减少症(refractory idiopathic thrombocytopenic purpura,RITP)的效果及其作用机制。方法:选择我院于2016年1月~2020年1月收治的难治性原发免疫性血小板减少症患者61例为研究对象,根据入院顺序经随机数字表法分成两组:对照组和研究组。对照组30例应用硫唑嘌呤治疗,研究组31例应用艾曲波帕联合硫唑嘌呤治疗。对比两组治疗效果、外周血Th淋巴细胞因子水平、B1淋巴细胞百分数、氧化应激反应指标。结果:研究组的治疗总有效率90.32%显著高于对照组(73.33%,P<0.05);治疗前,两组的白介素(interleukin,IL)-2、γ干扰素(interferon-γ,IFN-γ)、IL-4、IL-5水平对比无显著性差异(P>0.05);治疗后,两组的IL-2、IFN-γ水平均降低,IL-4、IL-5水平均升高,且研究组更优(P<0.05);治疗前,两组的CD19+淋巴细胞百分数、CD5+CD19+淋巴细胞百分数对比无显著性差异(P>0.05);治疗后,两组的CD19+淋巴细胞百分数、CD5+CD19+淋巴细胞百分数均比治疗前显著降低,且研究组显著低于对照组(P<0.05);治疗前,两组的总抗氧化能力(total antioxidant capacity,TAC)、超氧化物歧化酶(superoxide dismutase,SOD)、褪黑素(melatonin,MT)与谷胱甘肽(glutathione,GSH)水平对比无显著性差异(P>0.05);治疗后,两组的TAC、SOD、MT、GSH水平均比治疗前显著升高,且研究组显著高于对照组(P<0.05)。结论:艾曲波帕联合硫唑嘌呤治疗RITP的效果显著,其作用机制可能与改善患者的免疫功能及氧化应激状态有关,该方法值得推荐至临床广泛应用。     

大豆寡糖对断奶环江香猪生长性能和营养物质代谢的影响

为了探讨大豆寡糖(SBOS)作为抗生素替代物对断奶仔猪生长性能的影响及其作用机制,饲养试验选用21日龄断奶的环江香猪12头,随机分为2组,每组6头,分别饲喂添加0.5%SBOS日粮和抗生素对照日粮,试验期为14 d。记录每天的采食量,分别于试验开始和结束时称取空腹体重并采集血液,肝素抗凝离心分离血浆,测定生化参数和游离氨基酸水平。消化试验选用10头环江香猪,随机分为2组,处理同饲养试验。预试期4 d,正试期3 d,收集粪样,指示剂法测定干物质、粗蛋白和粗脂肪的消化率。结果表明,与抗生素对照组相比,SBOS组仔猪平均日采食量、日增重和料重比均无显著变化;血浆尿素氮和血氨含量显著下降,总蛋白含量显著升高(P<0.05);血浆甘氨酸、组氨酸、赖氨酸、精氨酸和蛋氨酸的含量均显著升高(P<0.05);粗蛋白和粗脂肪消化率有提高趋势。提示SBOS可替代抗生素用于断奶仔猪日粮。     

Tuning of electronic properties of one-dimensional cyano-bridged Cu-Ni, Cu-Pd, and Cu-Pt bimetallic assemblies by stereochemistry of ligands

Preparations, XPS and electronic spectroscopy, and magnetism of seven new one-dimensional cyano-bridged coordination polymers, chiral [Cu(RR-chxn)₂][Pd(CN)₄] · 2H₂O (1), [Cu(trans-chxn)₂][M(CN)₄] · 2H₂O (2, 4, and 6 for M = Pd, Ni, and Pt), and [Cu(cis-chxn)₂][M(CN)₄] · 2H₂O (3, 5, and 7 for M = Pd, Ni, and Pt) (RR-chxn = cyclohexane-(1R,2R)-diamine, trans-chxn = racemic trans-cyclohexane-(1,2)-diamine, and cis-chxn = racemic cis-cyclohexane-(1,2)-diamine) have been reported in view of tuning of their electronic properties by stereochemistry of chxn ligands and metal-substitution. Comparison of Cu 2p_1/2 and 2p_3/2 peaks of XPS and broad d-d bands around 18 000 cm⁻¹ of electronic spectra are described systematically for 1-7. Variable-temperature magnetic measurement shows that complexes 1-7 indicate weak antiferromagnetic interactions via cyano-bridges. Because of semi-coordination coupled with pseudo Jahn-Teller elongation and electrostatic interaction for 1, the axial Cu-N coordination bond distances of 2.330(7) and 3.092(8) Å are considerably longer than those of equatorial ones in the range from 2.016(6) to 2.030(6) Å. The former bond distances of 1 are intermediate values among the related Ni (2.324(6) and 3.120(8) Å) and Pt (2.34(1) and 3.09(1) Å) complexes.     

Land,livestock, and livelihoods: Changing dynamics of gender,caste, and ethnicity in a Nepalese Village

Over the past 10 years, Ghusel VDC, Lalitpur District has moved from primarily subsistence agriculture into the wider cash economy aided by the Small Farmers' Development Program (SFDP), which provides credit to farmers mainly for the purchase of buffalo for milk production, and by the National Dairy Corporation, which supports local dairy cooperatives. Analysis reveals that buffalo-keeping and milk sales are increasing the well-being of many households, while at the same time creating new inequalities in gender roles and responsibilities, greater inequities between Brahmin and Tamang residents in Ghusel, and placing pressures on the ecosystem for increased supplies of fodder and fuelwood. Evidence suggests that there is critical, need for attention to the social, and particularly gender-based, implications of maintaining livestock for milk sales and to the ecological underpinnings of this livelihood system.     

Structure and function of S-adenosylhomocysteine hydrolase

In mammals, S-adenosylhomocysteine hydrolase (AdoHcyase) is the only known enzyme to catalyze the breakdown of S-adenosylhomocysteine (AdoHcy) to homocysteine and adenosine. AdoHcy is the product of all adenosylmethionine (AdoMet)-dependent biological transmethylations. These reactions have a wide range of products, and are common in all facets of biometabolism. As a product inhibitor, elevated levels of AdoHcy suppress AdoMet-dependent transmethylations. Thus, AdoHcyase is a regulator of biological transmethylation in general. The three-dimensional structure of AdoHcyase complexed with reduced nicotinamide adenine dinucleotide phosphate (NADH) and the inhibitor (1′R, 2′S, 3′R)-9-(2′,3′-dihyroxycyclopenten-1-yl)adenine (DHCeA) was solved by a combination of the crystallographic direct methods program, SnB, to determine the selenium atom substructure and by treating the multiwavelength anomalous diffraction data as a special case of multiple isomorphous replacement. The enzyme architecture resembles that observed for NAD-dependent dehydrogenases, with the catalytic domain and the cofactor binding domain each containing a modified Rossmann fold. The two domains form a deep active site cleft containing the cofactor and bound inhibitor molecule. A comparison of the inhibitor complex of the human enzyme and the structure of the rat enzyme, solved without inhibitor, suggests that a 17° rigid body movement of the catalytic domain occurs upon inhibitor/substrate binding.     

Chiral Separation of G‐type Chemical Warfare Nerve Agents via Analytical Supercritical Fluid Chromatography

Chemical warfare nerve agents (CWNAs) are extremely toxic organophosphorus compounds that contain a chiral phosphorus center. Undirected synthesis of G‐type CWNAs produces stereoisomers of tabun, sarin, soman, and cyclosarin (GA, GB, GD, and GF, respectively). Analytical‐scale methods were developed using a supercritical fluid chromatography (SFC) system in tandem with a mass spectrometer for the separation, quantitation, and isolation of individual stereoisomers of GA, GB, GD, and GF. Screening various chiral stationary phases (CSPs) for the capacity to provide full baseline separation of the CWNAs revealed that a Regis WhelkO1 (SS) column was capable of separating the enantiomers of GA, GB, and GF, with elution of the P(+) enantiomer preceding elution of the corresponding P(–) enantiomer; two WhelkO1 (SS) columns had to be connected in series to achieve complete baseline resolution. The four diastereomers of GD were also resolved using two tandem WhelkO1 (SS) columns, with complete baseline separation of the two P(+) epimers. A single WhelkO1 (RR) column with inverse stereochemistry resulted in baseline separation of the GD P(–) epimers. The analytical methods described can be scaled to allow isolation of individual stereoisomers to assist in screening and development of countermeasures to organophosphorus nerve agents. Chirality 26:817–824, 2014. © 2014 The Authors. Chirality published by John Wiley Periodicals, Inc.     

Influence of Fluoride on Rat Kidney Antioxidant System: Effects of Methionine and Vitamin E

The aim of the study has been to determine and compare the influence upon the kidney antioxidative system, exercised by administration of vitamin E, and vitamin E in combination with methionine, under conditions of oxidative stress induced by sodium fluoride. The experiment was carried out on Wistar FL rats (adult males) that, for 35 days, were administered water, NaF, NaF with vitamin E, or vitamin E with methionine (doses: 10 mg NaF/kg of body mass/24 h, 3 mg vitamin E per 10 μl per rat for 24 h, 2 mg methionine per rat for 24 h). The influence of administered sodium fluoride and antioxidants upon the antioxidative system in kidney was examined by analyzing the concentration of malondialdehyde (MDA) and the activity of the most important antioxidative enzymes (SOD, total and both its isoenzymes, GPX, GST, GR, and CAT). The studies carried out confirmed the disadvantageous effect of the administered dose of NaF upon the antixodiative system in rats (increase in the concentration MDA, decrease activity of all antioxidative enzymes). The administration of vitamin E increased the activity of studied enzymes with the exception of glutathione reductase GR; it also reduced the procesess of lipid peroxidation. It has been found that combined doses of vitamin E and methionine were most effective in inhibiting lipid peroxidation processes. The results confirmed the antioxidative properties of methionine.     

Reorientation of Microfibrils and Microtubules at the Outer Epidermal Wall of Maize Coleoptiles During Auxin-Mediated Growth

Auxin-mediated elongation growth of isolated subapical coleoptile segments of maize (Zea mays L.) is controlled by the extensibility of the outer cell wall of the outer epidermis (Kutschera et al., 1987). Here we investigate the hypothesis that auxin controls the extensibility of this wall by changing the orientation of newly deposited microfibrils through a corresponding change in the orientation of cortical microtubules. On the basis of electron micrographs it is shown that cessation of growth after removal of the endogenous source of auxin is correlated with a relative increase of longitudinally orientated microfibrils and microtubules at the inner wall surface. Conversely, reinduction of growth by exogenous auxin is correlated with a relative increase of transversely orientated microfibrils and microtubules at the inner wall surface. These changes can be detected 30–60 min after the removal and addition of auxin, respectively. The functional significance of directional changes of newly desposited wall microfibrils for the control of elongation growth is discussed.     

Gamma-glutamylcysteine protects ergothioneine-deficient Mycobacterium tuberculosis mutants against oxidative and nitrosative stress

Mycobacterium tuberculosis (M.tb.), the causative agent of tuberculosis (TB), cannot synthesize GSH, but synthesizes two major low molecular weight thiols namely mycothiol (MSH) and ergothioneine (ERG). Gamma-glutamylcysteine (GGC), an intermediate in GSH synthesis, has been implicated in the protection of lactic acid bacteria from oxidative stress in the absence of GSH. In mycobacteria, GGC is an intermediate in ERG biosynthesis, and its formation is catalysed by EgtA (GshA). GGC is subsequently used by EgtB in the formation of hercynine-sulphoxide-GGC. In this study, M.tb. mutants harbouring unmarked, in-frame deletions in each of the fives genes involved in ERG biosynthesis (egtA, egtB, egtC, egtD and egtE) or a marked deletion of the mshA gene (required for MSH biosynthesis) were generated. Liquid chromatography tandem mass spectrometry analyses (LC-MS) revealed that the production of GGC was elevated in the MSH-deficient and the ERG-deficient mutants. The ERG-deficient ΔegtB mutant which accumulated GGC was more resistant to oxidative and nitrosative stress than the ERG-deficient, GGC-deficient ΔegtA mutant. This implicates GGC in the detoxification of reactive oxygen and nitrogen species in M.tb.     

In vitro studies of the rabbit immune system. IV. Differential mitogen responses of isolated T and B cells.

The mitogenic responses of separated rabbit lymphocyte populations functionally analogous to mouse T and B cells have been tested in vitro. Purified T cells were prepared by passage over nylon wool (NW) and purified B cells prepared by treatment with antithymocyte serum and complement (ATS + C). ATS + C kills 70% of peripheral blood lymphocytes (PBL's) and 50% of the spleen cells while passage over NW yields 40% of the applied PBL's and 5–23% of the applied spleen cells. NW-purified T cells from the spleen or PBL's respond fully to concanavalin A (Con A) but have a reduced response to phytohemaglutinin (PHA) and little or no response to goat anti-rabbit immunoglobulin (anti-Ig). PBL's that survive ATS + C (B cells) are stimulated by anti-Ig but not by Con A or PHA. B cells purified from spleen do not respond to Con A or PHA but will respond to anti-Ig under appropriate conditions. A full spleen B-cell response to anti-Ig required removal of Ig produced by the cultures that blocked anti-Ig stimulation. It is concluded that, for rabbit lymphocytes, Con A and PHA are primarily T-cell mitogens and that anti-Ig is primarily a B-cell mitogen. However, the mitogen response of unfractionated PBL or spleen cell populations indicates an overlap in reactivity. This could be due to cells sharing T and B properties, alteration of cell populations by the fractionation procedures used, or recruitment of one population in the presence of a mitogenic response of the other population.     

八种脑-肠肽侧脑室内注射对大鼠基础胃酸分泌的影响

用乌拉坦麻醉大鼠作急性实验,采用连续灌流胃并收集流出液的方法,观察向侧脑室内注射微量脑-肠肽对大鼠基础胃酸分泌的影响。实验结果如下:(1)雨蛙肽、八肽胆囊收缩素、促甲状腺素释放激素及四肽胃泌素均使总酸排出量增加;(2)生长抑素、胰多肽、P 物质、胰高血糖素则使总酸排出量减少;(3)上述肽类用侧脑室注射的剂量作肌肉注射,除四肽胃泌素也产生明显的刺激胃酸分泌作用外,对胃酸分泌均无明显影响。以上结果提示,脑内的一些肽类可能以神经递质或调制物的方式,参与中枢对胃酸分泌的调节。     

A chromium-tolerant plant growing in Cr-contaminated land

In this paper, a kind of Typhaceae plant species, Typha angustifolia L, with a high tolerance to Cr is described. Experiments were carried out to examine its ability to tolerant Cr and its physiological response. The results showed that there was no difference in growth, plant height, and biomass response to external Cr (VI) between the plants exposed to 100 microM Cr (VI) and control (0 microM), while increasing Cr levels to 200-800 microM induced a significant decrease in plant height and biomass, but no significant injury was detected, even for the plants exposed to 800 microM Cr. Chromium induced significant increases in superoxide dismutase (SOD) and peroxidase (POD) activities. Meanwhile, a significantly positive correlation was found between Cr and Mn or Cu in leaves and roots, respectively. The Cr tolerance of the plant appeared to be associated with the enhancement of SOD and POD activities and the improvement in uptake and translocation of the essential microelements.