新诊断2型糖尿病患者一相胰岛素分泌和胰岛素敏感性评估

目的评估新诊断2型糖尿病患者一相胰岛素分泌与胰岛素敏感性。方法对332例新诊断2型糖尿病患者按照精氨酸刺激试验的结果分为胰岛功能正常组和异常组来评估其胰岛素分泌和胰岛素敏感性的状况。结果（1）胰岛功能正常组的体重、体重指数（BMI）、腰围、臀围、股围、空腹血清真胰岛素和甘油三酯均显著高于胰岛功能异常组（均P〈0．01）；（2）校正性别、年龄、BMI和腰臀比后，胰岛功能正常组的真胰岛素增值（△TI）和胰岛素抵抗指数（HOMA—IR）均显著高于胰岛功能异常组（均P〈0．01）；（3）胰岛素分泌功能正常伴胰岛素抵抗的个体，胰岛素分泌功能正常不伴胰岛素抵抗的个体，胰岛素分泌功能缺陷伴胰岛素抵抗的个体和胰岛素分泌功能缺陷不伴胰岛素抵抗的个体分别占总人数的35．11％、5．02％、29．78％和30．09％。结论2型糖尿病个体可分为单纯胰岛功能异常、单纯胰岛素抵抗及胰岛功能异常伴胰岛素抵抗3类，其诊断和治疗需依据此病理生理状态的评估。     

低浓度乙醇对大鼠血管内皮损伤的保护作用

目的研究低浓度乙醇对低密度脂蛋白(LDL)诱导的血管内皮损伤的保护作用与内源性一氧化氮合酶抑制物的关系。方法SD大鼠在乙醚麻醉下,舌下静脉注射人血清LDL(4mg/kg)诱发血管内皮功能损伤。检测血中非对称性二甲基精氨酸(ADMA)、丙二醛(MDA)和一氧化氮(NO)的含量,并观察离体胸主动脉环的内皮依赖性舒张反应。结果单次静注LDL(4mg/kg)显著抑制乙酰胆碱(ACh)诱导的内皮依赖性舒张,增加血液中ADMA和MDA,降低NO水平。低浓度乙醇(10%,4ml/kg)能显著减轻LDL所致ACh诱导内皮依赖性舒张的损伤,能显著抑制ADMA和MDA浓度升高,降低NO浓度。但其他浓度乙醇(5%、15%,4ml/kg)对ADMA和NO浓度有较小的影响。结论低浓度乙醇对LDL诱导的血管内皮细胞损伤有保护作用,其保护作用与降低ADMA浓度有关。     

Inhibitory effects of the D(-)isomer of 3-hydroxybutyrate on cardiac non-esterified fatty acid uptake and oxygen demand induced by norepinephrine in the intact dog

The effects of ketosis on the norepinephrine-induced high rates of cardiac uptake of non-esterified fatty acids (NEFA = free fatty acids = FFA) and oxygen consumption were studied in anesthetized intact dogs. After a control infusion of norepinephrine (500 ng/kg.min into the left ventricle), the D(-) isomer or natural form of 3-hydroxybutyrate was infused intravenously as the arginine salt at rates of 20 mumol/kg.min in group A (10 dogs) and 80 mumol/kg.min in group B (10 dogs) and a second norepinephrine infusion was superimposed on the ketone treatment. At the time the effects of the second catecholamine infusion were measured, the arterial 3-hydroxybutyrate concentration averaged 1.2 +/- 0.1 mM in group A and 8.3 +/- 0.4 mM in group B, and the cardiac uptake of the ketone amounted to 17.4 +/- 0.6 and 35.8 +/- 5.3 mumol/min.100 g, respectively. Relative to the control norepinephrine infusion, the arterial NEFA concentration was reduced to 88 +/- 4% in group A and to 62 +/- 8% in group B, but the cardiac uptake of NEFA was significantly more depressed, to 65 +/- 7% in group A and to 35 +/- 8% in group B. These changes were not observed in ten non-ketotic animals under repeated norepinephrine infusion. Thus, ketosis inhibited the norepinephrine-stimulated uptake of NEFA, presumably through (1) a lowered availability of NEFA from arterial blood, attributable to a reduction of extracardiac lipolysis, and (2) competition of 3-hydroxybutyrate with NEFA for metabolism by the myocardium in the face of still high arterial NEFA concentrations, 1.7 +/- 0.1 mM in group A and 1.1 +/- 0.2 mM in group B. In both groups, the lowering of the contribution of NEFA to cardiac metabolism was associated with a reduction of the estimated oxygen demand per beat (ratio of cardiac oxygen consumption/min to the pressure-rate product), while the pressure response to norepinephrine was not modified. There was no evidence for abnormal cardiac function.     

The effect of oral administration of L–arginine on anal resting pressure and anodermal blood flow in healthy volunteers

Background Topical application of L–arginine, the precursor of nitric oxide, reduces anal resting pressure without significant side effects and may therefore be of benefit in the treatment of anal fissure. This in vivo study investigated the effect of orally administered L–arginine on anal resting pressure and anodermal blood flow in healthy volunteers. Methods Eight healthy volunteers took 3 sachets of Arginaid (Novartis Consumer Health, Breda, The Netherlands) containing 15 g L–arginine on a daily basis, for 7 days. At the start of the experiment (day 0) and on days 3 and 7, plasma levels of Larginine, anal resting pressures and anodermal blood flow were determined. Results Arginine plasma levels increased from 107.0±8.6 μmol/l (day 0) to 283.7±44.0 μmol/l on day 3 (p< 0.01) and remained elevated at day 7 (157.3±19.6 μmol/l, p<0.05). Anodermal blood flow and anal resting pressures were similar on days 0, 3 and 7. Conclusions Oral administration of 15 g arginine in healthy volunteers on a daily basis increased arginine plasma levels but had no influence on anodermal blood flow and anal resting pressure.     

口服L-精氨酸对冠状动脉疾病患者肱动脉内皮功能的改善作用

目的研究口服Ｌ精氨酸对冠心病患者肱动脉流量介导舒张功能（ＦＭＤ）的改善作用。方法采用随机、双盲、安慰剂对照、交叉试验设计，２０例患者平均６２８±９３岁，血压正常，冠状动脉造影证实存在冠状动脉疾病，分别口服Ｌ精氨酸（６７ｇ，３／ｄ）或安慰剂７天，间隔洗脱期７天；用高分辨率血管外超声测定治疗前后肱动脉ＦＭＤ和舌下含服硝酸甘油（０５ｍｇ）后肱动脉非内皮依赖性舒张，用高效液相（ＨＰＬＣ）测定治疗前后血浆Ｌ精氨酸水平的变化。结果口服Ｌ精氨酸１周后，肱动脉ＦＭＤ从１９４％±２６２％升高至６１５％±３０４％（配对ｔ检验：ｔ＝４４０，Ｐ＜０００１，２０例），血浆Ｌ精氨酸水平从８４３６±１５３８μｍｏｌ／Ｌ升高至１４３５６±２２９３μｍｏｌ／Ｌ（ｔ＝１０５０，Ｐ＜０００１，２０例）；安慰剂治疗前后肱动脉ＦＭＤ和血浆Ｌ精氨酸均无明显改变，试验过程中Ｌ精氨酸和安慰剂治疗前后肱动脉对舌下含服硝酸甘油的舒张反应性均无明显改变。结论短期口服Ｌ精氨酸可明显改善冠心病患者肱动脉ＦＭＤ，具有增强患者内皮功能的潜在临床意义。     

Impact of warning bleeding on the cortisol level in the fetus and neonatal RDS/TTN in cases of placenta previa

Objective: The purpose of this study was to examine the levels of hormones in umbilical vein blood that affect the neonatal respiratory function in cases of placenta previa and to evaluate the impact of warning bleeding on the hormone levels and neonatal respiratory outcomes such as respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN).

Methods: We analyzed data obtained from 33 placenta previa cases without fetal or maternal complications at 36–38 weeks of gestation. We measured the levels of hormones such as cortisol, arginine vasopressin, epinephrine and norepinephrine in umbilical vein blood using ELISA.

Results: Warning bleeding was found to be a significant factor protecting against neonatal RDS/TTN (p?=?0.049). The cortisol levels in the umbilical vein were significantly higher in the cases of previa with warning bleeding than in those without warning bleeding (p?=?0.020) and significantly higher in the no RDS/TTN cases than in the RDS/TTN cases (p?=?0.040).

Conclusions: Warning bleeding increases the cortisol level in cases of placenta previa. We suggest that genital bleeding may induce stress for both the mother and fetus, resulting in increased cortisol production, thus functioning as a protective factor against neonatal respiratory disorders.     

甲氧西林耐药葡萄球菌精氨酸代谢可移动原件研究

目的:研究临床分离的甲氧西林耐药葡萄球菌ACME携带情况以及阳性菌株流行特点。方法:收集2009年1月-2011年12月临床分离的葡萄球菌共363株,包括275株MRSA和88株MRSE,采用PCR方法对ACME编码基因arcA进行扩增。结果:275株MRSA中未发现ACME阳性菌株;88株MRSE中检测到ACME阳性菌株28株,阳性率31.8%,其中血液中分离率最高,占42.3%(11/26)。药敏结果显示,ACME阳性菌株除对利福平的耐药率较低外,对红霉素、氯洁霉素、庆大霉素、复方新诺明、四环素、左旋氧氟沙星的耐药率较高(均>30%),未发现耐利奈唑脘和万古霉素的菌株;ACME阳性菌株和阴性菌株对抗菌药物的耐药性没有显著差异(P>0.05)。结论:ACME阳性MRSE菌株在血流感染中有一定程度的流行;ACME具有广泛的水平转移功能,应加强该类菌株的监测。     

A Scoping Review on Arginine in Caries Prevention

ObjectivesEmerging science on arginine or arginine formulations has driven the need to examine the research in the field. The scoping study objectives were (1) to identify the extent, range, and type of evidence on the role of arginine or arginine formulations in caries prevention and (2) to explore the future scope of research on arginine-containing caries-preventive agents.MethodsA systematic search was performed in PubMed, Scopus, and Web of Science. In vitro studies, clinical trials, narrative reviews, systematic reviews and or meta-analysis, and umbrella reviews or meta-evaluation examining arginine or arginine formulations for caries prevention were included. The data-charting process involved extracting variables followed by evidence synthesis. Arginine variants investigated up to date were discussed to explore future scope of research.ResultsThirty-nine articles were included for review from 105 identified citations comprising of in vitro studies, clinical trials, and reviews. Most articles studied 1.5% arginine-fluoride toothpaste. Most studies were from Asia, followed by North America, with fewest studies from Europe and South America. Arginine or arginine formulations demonstrated a superior caries-preventive effect compared with their matched controls (including fluorides); however, the evidence is with high risk of bias. Until now, three arginine variants have been investigated with l-arginine monohydrochloride as the least explored variant.ConclusionsThe evidence on the caries-preventive effect of arginine or arginine formulations has a high risk of bias. High-quality clinical trials are needed to assess the caries-preventive potential of arginine in commercial formulations. The role of l-arginine monohydrochloride in caries prevention can further be explored by incorporating in self-applied and professionally applied caries-preventive agents.     

Arginine vasopressin dissociates the diuresis and natriuresis due to atrial natriuretic factor in man

The possible interaction between arginine vasopressin (AVP) and atrial natriuretic factor (ANF) in the control of urinary sodium and water excretion was investigated in man. Nine healthy male volunteers undergoing stable maximal water diuresis were studied on four separate occasions. Atrial natriuretic factor 15 pmol kg-1 min-1 or placebo (P) was concomitantly administered against a background infusion of either AVP 0.003 pmol kg-1 min-1 or P; thus the combinations P + P, AVP + P, P + ANF and AVP + ANF were studied. Atrial natriuretic factor caused a significant increase in sodium excretion (UNaV) [+56%], urinary flow rate (V) [+17%] and free water clearance (CH2O) [+23%]; creatinine clearance (Ccr) did not change. Arginine vasopressin reduced V (-58%) and CH2O (-68%) but did not alter UNaV or Ccr. On the AVP + ANF study day, UNaV increased (+64%) as with P + ANF, but V (-44%) and CH2O (-52%) continued to decrease below baseline levels; analysis of variance showed this antidiuresis reflected the prevalent effect of AVP rather than any specific interaction. These results show that AVP is able to dissociate the natriuretic and diuretic effects of ANF.