白藜芦醇体外抗白假丝酵母菌生物膜作用的初步研究

目的 研究白藜芦醇对体外白假丝酵母菌生物膜的影响.方法 采用XTT减低法评价白藜芦醇对白假丝酵母菌生物膜的影响;通过倒置显微镜、扫描显微镜观察该药对白假丝酵母菌生物膜的形态学影响.结果 白藜芦醇对白假丝酵母菌生物膜的SMIC50,SMIC80分别为128,256 μg/ml;当白藜芦醇浓度为256 μg/ml时对白假丝酵母菌的早期黏附及菌丝生长有抑制作用.结论 白藜芦醇对体外白假丝酵母菌生物膜有显著的抑制作用.     

柠檬提取物抑菌及抗病毒作用的研究

目的研究柠檬提取物抗微生物和保鲜作用。方法采用纸片法和稀释法对其抑菌效果和抗病毒作用进行了实验室观察。结果将柠檬提取物原液作1∶3200稀释液,对金黄色葡萄球菌标准株抑菌环直径为18 mm;1∶10稀释液对大肠埃希菌标准株抑菌环直径20 mm,1∶12800稀释液,抑菌环直径11 mm。柠檬提取物1:10稀释液对大肠埃希菌耐药株和克雷伯菌耐药株(产β-内酰胺酶)抑菌环直径分别为30 mm和20 mm,对白假丝酵母菌和啤酒酵母菌抑菌环直径分别为17 mm和14 mm。将1∶12800稀释度的柠檬提取物与单纯泡疹病毒混合作用,显示出明显的抗病毒效果。结论柠檬提取物对细菌及真菌有显著抑制作用,对产β-内酰胺酶菌株也有较强抑制作用;1∶12800稀释度的该提取物对单纯疱疹病毒Ⅰ型有明显的抗病毒作用。     

甲壳低聚糖碘液对微生物杀灭效果的观察

目的测定甲壳低聚糖碘液对金黄色葡萄球菌、大肠埃希菌、枯草芽胞杆菌、白假丝酵母菌的杀灭作用。方法用消毒学定量悬浮试验测定甲壳低聚糖碘液(含碘0．5％)的杀菌效果。结果定量悬浮试验结果表明：稀释度为1：32的甲壳低聚糖碘液对金黄色葡萄球菌的杀灭率为100％，而对大肠埃希菌100％的杀灭则需1：16的稀释度。原液对枯草杆菌芽胞的杀灭率为100％，而对白假丝酵母菌的杀灭率仅为52．35％。结论甲壳低聚糖碘液对细菌繁殖体及芽胞有较强的杀灭作用，对白假丝酵母菌作用较差。     

茶树油对白假丝酵母菌抑菌效果

目的观察茶树油对白假丝酵母菌的抑菌效果及其抗真菌作用机理。方法采用纸片扩散法和生化指标检测方法进行了试验研究。结果以含1-萜品-4醇与桉叶素为主要成分的茶树油对白假丝酵母菌最低抑菌浓度为体积分数1.56%;对该菌最低杀菌浓度为体积分数25%。茶树油处理的白假丝酵母菌的菌体蛋白质含量明显减少,菌体胆固醇及甘油三脂含量也明显低于正常对照菌株。结论茶树油在较低浓度条件下具有明显抑制和杀灭作用,茶树油有干扰菌体蛋白质、胆固醇及甘油三脂的合成作用从而产生抗菌作用。     

阿司匹林对白念珠菌生物膜的抑制作用

目的 研究阿司匹林对白念珠菌生物膜的抑制作用.方法 采用微量平板法制备白念珠菌生物膜,控温37℃,加同浓度阿司匹林,不同时期以活菌数判断其对白念珠菌生物膜的抑制作用;加不同浓度阿司匹林,同时期以活菌数判断其对白念珠菌生物膜的抑制作用.结果 1 mmol/L阿司匹林对白念珠菌芽管生成无抑制作用;阿司匹林对白念珠菌游离菌MIC为0.81-1.59 mmol/L;1mmol/L阿司匹林在不同时期对白念珠菌生物膜均有抑制作用;0.4～0.8 mmol/L阿司匹林对24 h白念珠菌生物膜均有抑制作用.结论 阿司匹林对白念珠菌芽管无抑制作用,对白念珠菌游离菌和生物膜均有抑制作用.     

白藜芦醇对葡萄球菌标准株抑菌作用研究

目的 探讨白藜芦醇(resveratrol,简称RES)对金黄色葡萄球菌抑菌作用。方法 以金黄色葡萄球菌标准株ATCC 25923(金葡菌标准株)作为研究主体检测RES对其的最低抑菌浓度(MIC),绘制不同浓度RES作用下金黄色葡萄球菌的生长曲线。结果 RES对金黄色葡萄球菌标准株MIC为0.256 mg/ml; 在RES浓度为1/4 MIC和1/2 MIC时,生长明显受抑,生长曲线不典型,对数生长期比正常对照组减缓; RES浓度为1MIC和2MIC时金黄色葡萄球菌完全受抑制,生长曲线完全失去正常生长状态,趋于平缓。结论 RES对金黄色葡萄球菌标准株抑制作用明显。     

富硒枸杞子对临床常见分离耐药菌体外抑菌活性的研究

目的探讨宁夏富硒枸杞子对6种临床常见分离耐药菌（金黄色葡萄球菌、表皮葡萄球菌、大肠埃希菌、铜绿假单胞菌、克柔假丝酵母菌、白色假丝酵母菌）体外抑菌活性的影响。方法采用微量稀释法及滤纸片扩散法,测定不同浓度的宁夏枸杞子对几种常见细菌和真菌的抑制效果,设置1．00、0．75、0．50、0．25g/mL4种枸杞子浓度和空白对照组共5组,测定最小抑菌浓度（M IC ）和最小杀菌浓度（M BC ）。结果不同浓度宁夏枸杞子提取物对耐药菌均有一定的抑菌效果,空白对照组,0．25、0．50、0．75、1．00 g/m L枸杞子浸出液对大肠埃希菌的抑菌环分别为0．00、（22．78±177;0．31）、（23．80±177;0．29）、（27．57±177;0．47）、（30．89±177;0．51）m m ;对铜绿假单胞菌的抑菌环分别为0．00、（23．07±177;0．45）、（24．16±177;0．49）、（29．34±177;0．39）、（35．16±177;0．34）mm ,并对铜绿假单胞菌绘制了生长曲线。不同浓度枸杞子提取物对大肠埃希菌和铜绿假单胞菌的抑菌作用强于其他4种细菌。结论枸杞子不同浓度提取物对临床分离耐药菌有明显的体外抑菌效果,为进一步全面开发宁夏富硒枸杞子的药物价值提供了依据。     

细菌超声分散计数仪在结核分枝杆菌最小抑菌浓度检测中的应用

目的 评估细菌超声分散计数仪在结核分枝杆菌(MTB)最小抑菌浓度(MIC)检测中的应用价值.方法 应用分散仪法和玻璃珠振荡研磨法2种细菌分散定量方法分别制备MTB标准菌株H37Rv(ATCC 27294)和28株MTB临床分离株菌悬液,接种于TREK Sensititre MYCOTB药敏板(简称MYCOTB),进行体...     

纳米银体外抗菌作用的实验观察

目的探讨纳米银在体外的抗菌作用,为开发利用纳米银提供依据。方法采用悬液定量抑菌试验方法,对纳米银抑制细菌繁殖体和酵母菌的效果进行了观察。结果以含纳米银600mg/L的纳米银溶液,在室温下作用60min,对大肠埃希菌、普通变形杆菌、铜绿假单胞菌的抑菌率为100%;含纳米银60mg/L该纳米银溶液对金黄色葡萄球菌和乙型溶血型链球菌的抑制率为100%。含量为600mg/L的纳米银溶液,在室温下作用60min,对白假丝酵母菌、黄曲霉菌和黑曲霉菌的抑制率为100%。随着纳米银浓度增加和作用时间延长,其抑菌作用增强。结论该纳米银制剂在悬液状态下对细菌和酵母菌具有明显的抑制作用,其抑菌作用强弱与纳米银含量和作用时间密切相关。     

412株假丝酵母菌的菌种鉴定及其耐药性分析

目的 分析临床假丝酵母菌属感染的种类及其对5种抗真菌药物的耐药性.方法 选择该院门诊及住院患者412例,采集其痰液、咽拭子、中段尿、大便或分泌物等,共检出假丝酵母菌属412株.使用沙保弱培养基培养并分离菌种,柯玛嘉显色培养基进行初步筛选,必要时进行假丝酵母菌属同化及糖（醇）的发酵试验进行菌种鉴定.采用法国生物梅里埃公司提供的ATB-FUNGUS3酵母样真菌药敏试剂盒,采用微量稀释法进行检测.标准菌株为白色假丝酵母菌ATCC90028、近平滑假丝酵母菌ATCC22019.结果 分离的412株假丝酵母菌属中,以白色假丝酵母菌和克柔假丝酵母菌为主;感染部位以下呼吸道（痰液）居多.在该院所用的5种抗真菌药物中,两性霉素B敏感性最高;热带假丝酵母菌对药物的耐药性明显高于白色假丝酵母菌、克柔假丝酵母菌及光滑假丝酵母菌.结论 检验人员应与临床医务人员沟通,鉴别定居菌与致病菌及其临床价值,指导临床合理用药.     

Abnormal Na+K+ cotransport function in a group of patients with essential hypertension

In 50 normotensive controls, the increase in erythrocyte Na+ concentration up to 12.4 +/- 2.0 mmol/l cells (mean +/- SD) ensures half-maximal stimulation of outward Na+,K+ cotransport fluxes. Forty-six out of sixty-five patients with essential hypertension required more than 16 mmol/l cells of internal Na+ concentration to obtain a similar effect, strongly suggesting an abnormal cotransport function. Seven out of fourteen hypertensive patients with normal Na,K cotransport function showed Na+,Li+ countertransport fluxes higher than the normal upper limit of 220 mumol (1 cells h)-1. Conversely, countertransport fluxes were normal in fourteen hypertensives with abnormal cotransport function. The above results indicate that the total population of patients with essential hypertension is heterogeneous and includes one subgroup of subjects with abnormal Na+,K+ cotransport function, and another with increased Na+,Li+ countertransport fluxes.     

Erythrocyte Li+/Na+ and Na+/H+ exchange, cardiac anatomy and function in insulin-dependent diabetics

It has been proposed that an increased activity of cell membrane Na+/H+ exchange, mirrored by increased erythrocyte Li+/Na+ exchange, may facilitate cell hypertrophy and hyperplasia. Patients with insulin-dependent diabetes mellitus may develop a specific cardiomyopathy with systolic and diastolic abnormalities and increased thickness of the left ventricle. Therefore, we have investigated the relationships between erythrocyte Li+/Na+ and Na+/H+ exchange and echocardiographic parameters in 31 male insulin-dependent diabetics (aged 17-68), in good metabolic control. Three had untreated mild hypertension. In all patients the urinary albumin excretion rate was less than 200 micrograms min-1. Ten patients had a Li+/Na+ countertransport higher than 0.37 mmol l-1 cell h-1, the upper normal limit for our laboratory (0.49 +/- 0.10, mean +/- SD). In comparison with the patients with normal countertransport, they had increased interventricular septum thickness and relative wall thickness (h/r). End diastolic volume and cardiac index were reduced while blood pressure and urinary albumin excretion rate were similar. In the whole study group, interventricular septum thickness was significantly correlated to Li+/Na+ exchange (r = 0.61, P less than 0.001) and Na+/H+ exchange (r = 0.35, P less than 0.05), independently of the effect of age and blood pressure. Posterior wall thickness was correlated to Li+/Na+ exchange (r = 0.38, P less than 0.05) and h/r to Li+/Na+ exchange (r = 0.41, P less than 0.05) and to Na+/H+ exchange (r = 0.44, P less than 0.05). Li+/Na+ exchange was negatively correlated to cardiac index (r = -0.37, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

L-type Ca2+ channels in the enteric nervous system mediate oscillatory Cl- secretion in guinea pig colon

The enteric nervous system regulates epithelial ion and fluid secretion. Our previous study has shown that the low (0.2-1 mM) concentrations of Ba2+, a K+ channel inhibitor, evoke Ca2+-dependent oscillatory Cl- secretion via activation of submucosal cholinergic neurons in guinea pig distal colon. However, it is still unclear which types of Ca2+ channels are involved in the oscillation at the neuroepithelial junction. We investigated the inhibitory effects of organic and inorganic Ca2+ channel antagonists on the short circuit current (I(sc)) of colonic epithelia (mucosa-submucosa sheets) mounted in Ussing chambers. The amplitude (412 +/- 37 microA cm(-2)) and frequency (2.6 +/- 0.1 cycles min(-1)) of the Ba2+-induced I(sc) in normal (1.8 mM) Ca2+ solution (n = 26) significantly decreased by 37.6% and 38.5%, respectively, in the low (0.1 mM) Ca2+ solution (n = 14). The I(sc) amplitude was reversibly inhibited by either verapamil (an L-type Ca2+ channel antagonist) or divalent cations (Cd2+, Mn2+, Ni2+) in a concentration-dependent manner. The concentration of verapamil for half-maximum inhibition (IC50) was 4 and 2 microM in normal and low Ca2+ solution, respectively. The relative blocking potencies of metal ions were Cd2+ > Mn2+, Ni2+ in normal Ca2+ solution. In contrast, the frequency of I(sc) was unchanged over the range of concentrations of the Ca2+ channel antagonists used. Our results show that the oscillatory I(sc) evoked by Ba2+ involves L-type voltage-gated Ca2+ channels. We conclude that L-type Ca2+ channels play a key role in the oscillation at the neuroepithelial junctions of guinea pig colon.     

大鼠血清和生理盐水中Mn2+浓度与MRI弛豫率变化的关系

目的 探讨在大鼠血清和生理盐水中Mn²⁺浓度与MR T1值及弛豫率间的变化关系。方法 配制Mn²⁺浓度为0、0.1、0.2、0.3、0.4、0.5、0.6、0.7及0.8 mmol/L的生理盐水和大鼠血清样本,采用小动物MR成像仪对各样本行T1W及T1-mapping成像,测量各样本T1值,并计算弛豫率。比较相同Mn²⁺浓度时2种介质间和不同Mn²⁺浓度间T1值的差异,并分析Mn²⁺浓度与弛豫率的关系。结果 Mn²⁺浓度为0时,生理盐水呈低信号,大鼠血清呈中等信号;随着Mn²⁺浓度升高,生理盐水和大鼠血清的T1W信号均逐渐增高,大鼠血清T1WI信号上升更快。相同Mn²⁺浓度的2种介质间,大鼠血清的T1值均小于生理盐水（P均<0.001）。大鼠血清和生理盐水中,不同Mn²⁺浓度样本间T1值差异均有统计学意义（P均< 0.001）,随着Mn²⁺浓度增大,T1值均逐渐减小,两两Mn²⁺浓度间比较差异均有统计学意义（P均<0.001）。大鼠血清及生理盐水中,Mn²⁺浓度与弛豫率呈近似线性关系。结论 Mn²⁺可缩短大鼠血清和生理盐水这2种液体介质的T1值,且Mn²⁺浓度与弛豫率呈线性关系。     

The effects of ions on antibacterial activity of ofloxacin and ceftriaxone.

MIC and MBC values of ofloxacin and ceftriaxone were investigated against Staphylococcus aureus in MHB and MHB containing additional Mg2+, Al3+, Fe3+, Ca2+, Zn2+, Cu2+. The addition of Mg2+, Al3+, Fe3+ increased the MIC and MBC of ofloxacin and the MBC of ceftriaxone. However, the addition of these cations did not change the MIC of ceftriaxone. Our findings suggest that these interactions might be due to the formation of chelates between metal ions and antibiotics. These results also indicate that some cations may have an important role in the antibacterial activity of antibiotics.     

Abnormal Na+-K+ ATPase kinetics in a subset of essential hypertensive patients

We have performed a kinetic analysis of the interaction of Na+-K+ ATPase with internal Na+ in erythrocytes of 30 normotensive controls and 72 essential hypertensive patients. Neither the maximal rate of ouabain-sensitive sodium efflux (Vmax) nor the internal Na+ content required for half-maximal stimulation (K50%) were significantly different between normotensive and hypertensive patients. Nevertheless, using the 95% confidence limits of the K50% in the normotensive group as a cut-off point, 13 (18.06%) essential hypertensive patients exhibited increased values of this parameter (29.16 +/- 4.31 mmol l-1 cells) revealing decreased affinity of Na+-K+ ATPase for internal Na+ (Pump-hypertensives). The Vmax was also higher in the Pump '-' subset (14.08 +/- 4.85 mmol (1 cells h)-1 vs. 6.92 +/- 1.80; P = 0.0002) and 10 of these 13 hypertensives exhibited a Vmax above the upper end limit of 10.5 mmol (1 cells h)-1, suggesting a compensatory effect. No differences were observed between the Pump '-' subset and the remaining 59 hypertensives without Na+-K+ pump abnormality when basal erythrocyte Na+ content and clinical parameters of hypertension were examined. Decreased apparent affinity of Na+-K+ pump for internal Na+ present in 9-27% of essential hypertensives may be implicated in pathogenetic mechanisms of hypertension.     

A simple and rapid method for the determination of the concentrations of magnesium, sodium, potassium and sodium, potassium pumps in human skeletal muscle

1. For the diagnosis of electrolyte disorders, data on skeletal muscle composition are often valuable, but rarely available. We have therefore developed a simple and rapid needle biopsy procedure for the determination of the concentrations of K+, Na+, Mg2+ and Na+, K+-pumps in muscle. 2. Using a Bergstr?m needle, biopsies weighing around 25 mg were taken from the vastus lateralis muscle of 18 normal subjects (aged 44-86 years) and extracted with trichloroacetic acid (TCA). The concentrations of K+, Na+ and Mg2+ were 90.7 +/- 1.8, 31.9 +/- 1.6 and 9.5 +/- 0.2 mumol/g wet wt., respectively (means +/- SE). 3. The TCA extraction gave the same values as digestion with 65% HNO3 or 35% H2O2, could be used over the weight range 10-55 mg and showed a Mg2+ recovery of 101.7%. 4. The concentration of Na+, K+-pumps was quantified as the total capacity for [3H]ouabain binding. In vastus lateralis biopsies obtained from six normal subjects the mean value was 258 +/- 16 pmol/g wet wt. 5. Comparison of the concentrations of K+, Mg2+ and [3H]ouabain-binding sites in samples obtained post mortem showed modest variation among different muscles with varying fibre composition. 6. Measurements of the concentrations of K+, Na+, Mg2+ and Na+, K+-pumps in duplicate biopsies of the vastus lateralis yield values which seen representative for the total pool of skeletal muscle fibres and can be performed within a few hours.(ABSTRACT TRUNCATED AT 250 WORDS)     

不同计数板对计算机辅助精子分析系统检测影响探讨

目的 探讨不同精子计数板对计算机辅助精子分析结果的影响.方法 采用计算机辅助分析对2013年2月10日～4月30日,48份门诊和住院患者标本分别用三块计数板进行精子浓度和精子活力检测,并对结果进行F检验;对这三块计数板用Filmetrics F20激光间隙测量仪进行多位点深度检测,根据平均浓度判断是否合格.结果 用A型（金属板）、B型（玻璃板）和C型（Macro板）计数板测得的平均精子浓度分别为：（50.3±27.1）×106/ml,（76.5±30.5）×106/ml,（65.5±24.2）×106/ml,三者之间差异有统计学意义（F=22.10,P＜0.05）;三块计数板所测得的平均精子活力无差异;A型、B型计数板平均深度分别是7.74 μm,13.01 μm,均不合格,C型10.01 μm判为合格.结论 计算机辅助精子分析配套用的精子计数板严格按照《人类精液检查与处理实验室手册》第5版的要求进行验收和定期复检,可确保精子分析质量.建立精子计数的室内质量控制可监测计数板的深度变化.     

谷氨酰内切酶的原核表达及生物化学特性分析

摘要：目的：原核表达谷氨酰内切酶,评价其生物化学特性。 方法：PQE60Glu△Cmut5质粒转化大肠埃希菌M15,经异丙基β-D-硫代半乳糖（IPTG）诱导、Ni-NTA亲和层析等步骤获得重组谷氨酰内切酶。以偶氮酪蛋白为底物测定其酶活性,分析底物浓度、温度、pH、金属离子和EDTA对酶活性的影响。采用SDS-PAGE电泳和质谱研究谷氨酰内切酶对Hb的酶解作用。 结果：重组谷氨酰内切酶可以在M15菌中高效表达,并具有较高的酶活性。SDS-PAGE分析显示其相对分子质量约33 000。谷氨酰内切酶的Km值为0.26 mmol/L,最适反应温度为55 ℃,最适pH为8.0,Ca²⁺和Mg²⁺能激活酶活性,Fe²⁺、Zn²⁺、Mn²⁺和EDTA则对酶活性有抑制作用。SDS-PAGE和质谱分析显示重组谷氨酰内切酶对Hb有特异性水解作用。 结论:谷氨酰内切酶在大肠埃希菌M15中能获得高效表达,具有特有的生物化学特性和严格的底物水解特异性。     

CHANGES IN PLATELET FREE Ca2+ CONCENTRATION AFTER CHRONIC DIGOXIN TREATMENT

Summary— Cell Na+ and Ca²⁺ concentrations control each other by various mechanisms. In excitable cells from various origins, Ca²⁺ extrusion from the cell and its entry are dependent for a large part on the activity of the Na+, Ca²⁺-countertransport system. Cytosolic free Ca²⁺ concentration is also controlled by the Na+–H+ exchange activity. To analyze the changes in cytosolic Ca²⁺ concentration accompanying the reduction of the membrane Na+ gradient, cytosolic free Ca²⁺ concentration ([Ca²⁺]_i) was measured by fluorescent dyes in platelets and erythrocytes from healthy subjects, before and during digoxin treatment (0.25 mg/day for 6 days). [Ca²⁺]_i was increased in platelets from 169±30 to 321±61 nmol/l ( n = 7, P <0.02) and unchanged in erythrocytes (121±6 and 104±7 nmol/l). This increase in platelet [Ca²⁺]_i was not accompanied by a change in serotonin content (5.43±0.67 vs 5.49±0.61 10⁻⁷ mol per 10¹¹ cells) and could not be reproduced by in vitro addition of 10⁻⁴ mol/l ouabain (198±33 vs 186±73 nmol/l). The enhanced [Ca²⁺]_i in platelets is thus not a short-term consequence of a reduced membrane Na+ gradient, but reflects either the overload of intracellular Ca²⁺ stores or an enhanced in vivo stimulation by hormones or neurotransmitters.