超高效液相色谱-串联质谱法同时快速检测微量血清中6种脂溶性维生素

目的 建立超高效液相色谱-串联质谱法（UPLC-MS/MS）同时快速检测微量血清中维生素A、维生素D（25-OH-VD2 、25-OH-VD3 ）、维生素E（α-、β-和γ-生育酚）的方法。方法 血清中脂溶性维生素经甲醇-乙腈（50:50, v/v)沉淀蛋白、正己烷萃取,以Phenomenex Kinetex F5色谱柱为分离柱,2.5 mmol/L甲酸铵-0.1%甲酸水溶液和甲醇为流动相,梯度洗脱,电喷雾电离（ESI+ ）、多反应监测（MRM）模式下检测,同位素内标法定量。结果 血清中6种脂溶性维生素线性范围内线性关系良好,相关系数 r >0.995;6种脂溶性维生素的检测限为0.20~1.25 ng/ml,定量限为0.39~3.88 ng/ml;加标回收率为86.6%~107.7%,日内精密度<9.6%,日间精密度<9.3%。NIST标准参照品SRM 968f验证方法准确度,结果偏差均在5%以内。结论 本方法准确度高、重现性好、用血量少,适于婴幼儿等采血困难者微量血样中多种脂溶性维生素的同时快速检测。     

恒河猴tPA基因的克隆、测序与真核表达

本试验采用高浓度乙二醇（EG-8）作为胚胎冷冻保护剂,以高浓度的半乳糖作为解冻稀释液,对MMTV-Wnt-1转基因小鼠的早期囊胚进行玻璃化冷冻保存。结果在EG-2中平衡4-6min和解冻时间为3-5min时获得了最佳冷冻效果。此条件下冷冻胚胎的总回收率为88.61%（109/123）;回收胚胎在体外发育率达88.99%（97/109）;孵化率达81.65%（89/109）;发育胚胎的移植出生率为38.36%（69/181）;冷漠胚胎移植出生后经PCR检测一半小鼠整合阳性。结果表明使用高浓度的乙二醇作为冷冻保护剂和以高浓度的半乳糖作为冻稀释液能有效地保存转基因小鼠胚胎。     

长循环脂质体的研究进展及其在核医学中的应用

脂质体作为药物载体具有很多优点,但是其主动靶向性和稳定性较差,聚乙二醇或与配体连接的聚乙二醇修饰的脂质体,即长循环脂质体,具有延长脂质体在血液循环中的半衰期、提高其稳定性、改变脂质体在体内的生物学分布,赋予脂质体靶向性的优点。本文主要综述了长循环脂质体的研究进展及其在核医学中的应用。     

不育患者Y染色体AZF微缺失的分析

目的探讨Y染色体上AZF区域微缺失与男性不育的关系。方法采用多重PCR技术,对20例不育患者AZF4个区的l5个序列标签位点（STS）进行了微缺失检测和细胞遗传学检查。结果20例患者中共有3例发现微缺失（15%）。结论AZF微缺失是导致男性不育的重要原因之一,细胞遗传学检查与AZF微缺失无相关性。     

孕妇外周血中胎儿有核红细胞数量与妊娠高血压综合征的关系

目的 探讨孕妇外周血中胎儿有核红细胞数量（fetal nucleated red blood cells，FNRBC）数与妊娠高血压综合征的关系。方法 对128名孕龄32～42周，年龄24～35岁的孕妇外周血进行单密度梯度离心，对分离后的细胞进行制片、染色，显微镜下进行FNRBC计数，比较组间差异。结果 38名正常妊娠组孕妇外周血中FNRBC数目为（6．4667±2．5141）个／5ml，36名轻度妊高征组孕妇外周血中FNRBC数目为（9．5300±2．3286）个／5ml，28名中度妊高征组孕妇外周血中FNRBC数目为（13．7100±4．0286）个／5ml，26名重度妊高征组孕妇外周血中FNRBC数目为（31．5000±9．4086）个／5ml。四组间比较P值均小于0．05。结论 妊高征组孕妇外周血FNRBC数目明显升高，为妊高征的临床预测和评估提供了一条新思路。     

Surface Modification of Poly(lactide-co-glycolide) Nanospheres by Biodegradable Poly(lactide)-Poly(ethylene glycol) Copolymers

The modification of surface properties of biodegradable poly(lactide-co-glycolide) (PLGA) and model polystyrene nanospheres by poly(lactide)-poly(ethlene glycol) (PLA:PEG) copolymers has been assessed using a range of in vitro characterization methods followed by in vivo studies of the nanospheres biodistribution after intravenous injection into rats. Coating polymers with PLA:PEG ratio of 2:5 and 3:4 (PEG chains of 5000 and 2000 Da, respectively) were studied. The results reveal the formation of a PLA: PEG coating layer on the particle surface resulting in an increase in the surface hydrophilicity and decrease in the surface charge of the nanospheres. The effects of addition of electrolyte and changes in pH on stability of the nanosphere dispersions confirm that uncoated particles are electrostatically stabilized, while in the presence of the copolymers, steric repulsions are responsible for the stability. The PLA:PEG coating also prevented albumin adsorption onto the colloid surface. The evidence that this effect was observed for the PLA:PEG 3:4 coated nanospheres may indicate that a poly(ethylene glycol) chain of 2000 Da can provide an effective repulsive barrier to albumin adsorption. The in vivo results reveal that coating of PLGA nanospheres with PLA:PEG copolymers can alter the biodistribution in comparison to uncoated PLGA nanospheres. Coating of the model polystyrene nanospheres with PLA:PEG copolymers resulted in an initial high circulation level, but after 3 hours the organ deposition data showed values similar to uncoated polystyrene spheres. The difference in the biological behaviour of coated PLGA and polystyrene nanospheres may suggest a different stability of the adsorbed layers on these two systems. A similar biodistribution pattern of PLA:PEG 3:4 to PEG 2:5 coated particles may indicate that poly(ethylene glycol) chains in the range of 2000 to 5000 can produce a comparable effect on in vivo behaviour.     

PEG-Hemoglobin as a resuscitation solution in the treatment of hypovolemic shock in the anesthetized rat

This study was designed to determine the advantages of using the hemoglobin-based oxygen carrier, polyethylene glycol conjugated bovine hemoglobin (PEG-Hb), as an additive to Ringer's lactate solution (RLS) for the treatment of acute hemorrhage in anesthetized female rats. Different compositions of PEG-Hb and RLS were administered intravenously in a paradigm that provided 30 ml/kg of resuscitation fluid following an episode of 15 min of hypotension. Hypotension was achieved by the removal of blood (1 ml/min) from the femoral vein until the mean arterial pressure was lowered to or below 50 mmHg and subsequently maintained until resuscitation. Short-term cardiovascular assessment showed that resuscitation fluids containing PEG-Hb resulted in higher mean arterial pressure, aortic blood flow, renal blood flow, and less dramatic shifts in arterial base excess and respiratory blood gases than plain RLS. The long-term survival experiment showed lower lactate dehydrogenase, alkaline phosphatase, and serum glutamic pyruvic transaminase levels in most groups resuscitated with solutions containing PEG-Hb, but no differences in survival (100%) were observed. The data suggest that the addition of PEG-Hb to RLS improves its resuscitative effects. Specifically, a solution of 50% RLS:50% PEG-Hb appeared to have the most favorable cardiovascular and metabolic effects in this anesthetized rat hypovolemic shock resuscitation model. Presumably, the improved effects seen with the addition of PEG-Hb were due to its innate plasma expansion and oxygen-delivery capabilities.     

Rectal Mucosa Damage in Rabbits After Subchronical Application of Suppository Bases

The effect of suppository bases on rabbit rectal mucosa was investigated using six triglyceride bases, polyethylene glycol, and a triglyceride base combined with monoglycerides or fatty acids and methyl esters of those acids. Rectal irritation was evaluated and scored according to defined pathological features. Pure triglycerides and a triglyceride to which a nonionic surfactant was added caused severe mucosal damage with ulceration and inflammation. Hyperemia was characteristic for irritation by polyethylene glycol suppositories. Mucosal damage by a pure triglyceride combined with monoglycerides or fatty acids and methyl esters of those acids was similar but statistically less pronounced than with all other bases.     

The cocaine-insensitive component of non-exocytotic efflux of noradrenaline from adrenergic axons in the isolated rat tail artery

Summary The working hypothesis was that the cocaine-insensitive component of non-exocytotic efflux of noradrenaline represents diffusion of the unprotonated amine across the axonal membrane. It was tested by examination of the effect of changing axoplasmic pH —and thus the fraction of extravesicular noradrenaline in the unprotonated form — on the overflows of endogenous noradrenaline and 3,4-dihydroxyphenylethylene glycol from rat tail arteries. The catechols were assayed by liquid chromatography with amperometric detection. To dissipate the H⁺ gradient across the axonal membrane, the tissues were incubated in media of different pH, in which Na⁺ was completely replaced with K⁺ and which were HCO₃ ^– - (and Ca²⁺-)free. Exposure of the tissues to these media produced substantial, but reversible increases in the overflow of noradrenaline. Subsequently, the overflows of both noradrenaline and the glycol kept rising, but their ratio did not change.Cocaine (0.1 mmol/1) lowered the (noradrenaline overflow: glycol overflow) ratio significantly. The ratio observed in its presence increased steeply with decreasing external and, presumably, axoplasmic pH. Addition of valinomycin and carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (1 mol/1 each) to the cocaine-containing media more than doubled the overflows without altering significantly the ratio. Under identical conditions, the overflow of noradrenaline from preparations with inactive neuronal monoamine oxidase did not decrease with decreasing pH.Since, in the presence of cocaine, the overflow ratio increased — rather than decreased — with decreasing pH, and because the overflow or noradrenaline from preparations with inactive monoamine oxidase did not decline with pH, the cocaine-insensitive component of noradrenaline efflux does not seem proportional to the axoplasmic concentration of the unprotonated amine. The data can, however, be accounted for by postulating that the component reflects the concentration of the protonated form of noradrenaline.     

甘糖酯对实验糖尿病大鼠粘附分子-CD54、CD106、CD62p的影响

目的观察糖尿病大鼠肾脏、主动脉等粘附分子的变化及甘糖酯干预的影响,为早期防治糖尿病并发症提供科学依据.方法实验分正常对照、糖尿病对照、高、低剂量甘糖酯共4组,通过免疫组织化学方法观察大鼠肾脏和主动脉CD54和/或CD106的表达,应用流式细胞仪测定血中单个核细胞表面CD54、血小板表面CI)62p的表达水平;应用甘糖酯治疗8周后,观察上述指标的变化.结果(1)血单个核细胞表面CD54测定表明高剂量甘糖酯组有明显降低,(CD54高=36.04±11.01%,VS CD54DM=65.09±14.92%,P＜0.05),而低剂量甘糖酯组降低不明显;甘糖酯时血小板表面CD62P表达影响不大;(2)肾脏和主动脉CD54、CD106免疫组化显示甘糖酯能降低其表达并减轻组织病理变化,且与剂量有关.(3)甘糖酯有降低血糖的作用,并与剂量有关(高剂量组BG治疗前=20.93土4.22mmol@L-1,BG治疗后=15.76±2.39mmol@L-1,P＜0.05;低剂量组BG治疗前=17.35±1.13mm0l@L-1,BG治疗后=13.52±6.24mmol@L-1,P＞0.05).结论糖尿病粘附分子的增加可能是糖尿病肾病和大血管病变的重要发病因素,甘糖酯可降低CD54、CD106对糖尿病并发症有延缓和改善作用.