Pharmacokinetics--a relevant factor for the choice of a drug?

Pharmacokinetics may be utilized as a tool in the drug development process, either with respect to therapeutics or in allowing a drug's disposition characteristics to be defined. If two drugs of the same class have a similar dose-efficacy profile, then the favourable/unfavourable balance of the pharmacokinetic characteristics of the drugs may determine the drug of choice. Pantoprazole, a proton pump inhibitor, appears to meet the above criteria and has been found to exhibit reliable, predictable pharmacokinetic characteristics as opposed to other members of the class. The pharmacokinetics of pantoprazole over a range of intravenous and oral doses are described in healthy volunteers and are compared with values obtained for omeprazole. Studies in patients with severe cirrhosis, renal failure, and in the elderly are also described as well as potential interactions due to food and five other drugs.     

MK801慢性处理引起皮层神经元3H-GABA释放的改变

Excitatory amino acids are involved in acute and chronic neurodegenerativediseases.Little is known about the potential consequences of chronic blockade of NMDA receptors (onesubtype of excitatory amino acid receptors).Receptor function measured as ³H-GABA release inculture media after pretreatment with MK801 was studied in rat cortical neurons in primary cultures.Cultured neurons were exposed to 1μmol·L^-1 MK801 for 4 days since the 14th day.Glutamate( 1 mmol·L^-1 )evoked ³H-GABA release was shown to be significantly increased(control0.2174‰±1.40‰; MK801 treatment 0.763%±0.192%).KCl 40 mmol·L^-1 stimulation showedno such effect.This result suggests that the NMDA receptor function of releasing neurotransmitterschanged after chronic treatment with noncompetitive antagonists.     

The three-way stopcock may be a weak component of total intravenous anaesthesia

Background: An intravenous line is needed to administer anaesthesia, particularly when total intravenous anaesthesia (TIVA) is performed. A disadvantage of TIVA is that the intravenous concentration of anaesthetics cannot be easily measured compared with volatile anaesthetics. If a three-way stopcock is accidentally unscrewed, TIVA drugs cannot reach the patient's veins, thus resulting in inadequate anaesthesia levels, possibly resulting in awareness. We therefore measured the required torque to open five different brands of three-way stopcocks in an attempt to make an intravenous-line including all elements safer.
Methods: The torque required to open one, two or three three-way stopcocks being connected in a perpendicular manner was measured with a biaxial servo hydraulic material testing machine.
Results: The force required to open three-way stopcocks connected with an intravenous catheter ranged in five different stopcock models from 5.03±0.75 to 2.21±0.51 N respectively; with two three-way stopcocks from 2.68±0.42 to 1.31±0.59 N, respectively, and with three three-way stopcocks from 1.29±0.27 to 0.82±0.05 N, respectively.
Conclusion: Turning a three-way stopcock to become loose with possibly leaking drugs requires minimal amounts of force and decreases significantly if not connected in-line.     

肺源性心脏病急性发作期免疫功能的改变

目的:观察肺源性心脏病(简称肺心病)急性发作期患者免疫功能的变化。方法:选择南华大学附属第一医院2004-11/2006-01收治慢性肺心病急性发作期患者60例为肺心病组,于急性加重期入院第2天7:00,空腹抽取静脉血,采用流式细胞仪检测T细胞亚群CD3 、CD4 、CD8 及自然杀伤细胞活性,免疫浊度法检测体液免疫指标(IgG,IgM,IgA及补体C3)。以同期60例健康体检者为对照。结果:120例是否受试者均进入结果分析。①T细胞亚群:肺心病组CD3 ,CD4 水平低于对照组(0.52±0.06,0.62±0.04;0.32±0.06,0.41±0.06;P均<0.05),CD4 /CD8 高于对照组(1.96±0.26,1.84±0.78,P<0.05)。②免疫血清指标:肺心病组IgA、补体C3及自然杀伤细胞活性低于对照组[(1.26±0.74),(2.45±0.85)g/L;(6200±217),(9960±302)mg/L;0.34±0.08,0.57±0.07;P均<0.05]。结论:肺源性心脏病急性发作期患者的细胞免疫和体液免疫功能均受损,尤以细胞免疫功能受损更突出,且与病情呈平行关系。     

薄层扫描法测定熊胆引流物中胆汁酸含量

熊胆向以贵重药材闻名,被称之为稀有药品,为开发熊胆资源,解决熊胆奇缺问题,我校解剖教研室已成功地完成了人工引流熊胆汁技术,可随时进行人工引流获取熊胆汁。为了确定胆汁的质量指标,了解其主要成分,我们进行了引流胆汁与天然熊胆的分析。文献报道,熊胆中主要含熊去氧胆酸(ursodesoxycholic acid,UDCA)、鹅去氧胆酸(cheno desoxycholic acid,CDCA)、胆酸(cholic acid,CA)、去氧胆酸(deoxycholic,acid DCA)等。     

Effects of lovastatin (mevacor) on platelet function in hypercholesterolemia in patients with ischemic heart disease]

The impact of a 4-week course of lovastatin (mevacor) therapy on platelet function was examined in 26 patients with coronary heart disease concurrent with hypercholesterolemia (the baseline plasma cholesterol level was 250 mg% or more). The agent was given in a daily dose of 20-40 mg. The agent in this dose was found to have no action on the thromboxane-prostacyclin balance in plasma, on the degree of ADP-induced aggregation and lipid peroxidation in platelets, phospholipid composition and levels of ester-bound cholesterol in platelet membranes. Free cholesterol tended to increase at the end of the 4th week of treatment. Despite the effective reduction of plasma levels of total and LDL cholesterols whose action on platelets is well known, there was no estimated decrease in the activity of platelets during lovastatin therapy.     

Allysine peptides and derivatives

Allysine, which is synthesized enzymatically in vivo starting from lysine, is a very important crosslink precursor in proteins. We describe the chemical synthesis of allysine derivatives starting from 3,4-dihydro-2H-pyran. Two independent synthetic routes to prepare allysine peptides and derivatives are presented. The synthesized compounds are characterized by spectroscopic methods including ¹³C-n.m.r. The reactivity of the aldehyde function is shown to be extremely high. An unexpected nucleophilic attack of the allysine amide nitrogen upon the aldehyde group is described. This ring-closure reaction is not expected to take place in native collagen; however, denatured peptides containing allysine may react similarly as the model peptides presented in this paper.     

‘In different situations,in different ways’: male sex work in St. Petersburg,Russia

We conducted a qualitative study of male sex work in St. Petersburg Russia with a focus on social vulnerabilities, HIV-risk perception and HIV-related behaviours. In-depth interviews were conducted with individuals knowledgeable about male sex work through their profession and with male sex workers themselves. Male sex work involves a variety of exchanges, including expensive vacations, negotiated monetary amounts or simply access to food. Methods of finding clients included the Internet, social venues (e.g. gay clubs and bars) and public places (e.g. parks). Use of the Internet greatly facilitated male sex work in a variety of ways. It was used by both individuals and agencies to find clients, and appeared to be increasing. Men often reported not being professionally connected to other male sex workers and limited disclosure about their work. Many were aware of the work-related risks to personal safety, including violence and robbery by clients. Perceived risk for HIV was mostly abstract and several exceptions to condom use with clients were noted. Alcohol use was reported as moderate but alcohol was consumed frequently in association with work. These data suggest that the most salient risks for male sex workers include professional isolation, threats to personal safety, limited perceived HIV risk and sub-optimal levels of condom use.