Dynamics of HIV replication in lymphocytes and the efficacy of protease inhibitors

Using a system that allows transfection of resting peripheral blood lymphocytes (PBLs) two questions were addressed: the kinetics of HIV replication from the state of proviral latency, and the impact of different parameters on the efficacy of protease inhibitors to control HIV replication. PBLs were transfected with an infectious full length HIV-DNA harboring a luciferase reporter gene and activated thereafter. Ritonavir was added at different times at doses ranging from to 0.06 to 1 microM. Viral expression was assessed by quantifying luciferase activity in cell extracts and levels of p24 HIV antigen in culture supernatants. After transfection and cell activation, intracellular expression of HIV proteins, as assessed by luciferase detection, occurred within 2 hr. HIV-gag p24 antigen was detected in culture supernatants between 6 and 8 hr post-activation. Ritonavir was effective in blocking viral replication when given within 4 hr following HIV reactivation, but a delay in ritonavir administration or breaches in ritonavir levels after 6 hr from transfection resulted in viral escape. HIV reactivation from proviral latency in PBLs is an extremely rapid process, faster than estimated from previous models. These data stress the need for maintaining effective antiretroviral concentrations to block completely viral replication.     

Clinical profiling of recombinant follicle stimulating hormone (rFSH; Puregon): relationship between serum FSH and efficacy

Single-dose and multiple-rising dose studies of recombinantfollicle stimulating hormone (rFSH) in hypogonadotrophic maleand female volunteers demonstrated that the rate of FSH absorptionafter i.m. injection is higher in men than in women. In theabsence of endogenous FSH, a correlation between serum FSH andbody weight became apparent. The elimination half-life of rFSHwas not different between the sexes and was comparable withurinary FSH. However, the in-vitro bio:immuno ratio of serumFSH was significantly higher after the administration of rFSHthan after urinary FSH. When rFSH was administered daily witha fixed dose, steady state levels were reached within 3-5 days.Serum FSH concentrations increased in a dose-dependent mannerwhen the daily dose was increased weekly over 3 weeks from 75to 225 IU. In hypogonadotrophic women, rFSH induced normal folliculargrowth whereas oestrogen synthesis was impaired. In women pituitarysuppressed by a high-dose oral contraceptive, the daily administrationof 150 IU rFSH for 1 week induced more and larger antral folliclesthan the same regimen with urinary FSH, whereas the serum immunoactiveFSH concentrations measured 24 h after each dosing were similar.It is concluded that even though equal or lower serum immunoactiveFSH concentrations were obtained following the administrationof rFSH compared with urinary FSH, circulating bioactivity FSHconcentrations were higher. Therefore, the conventional ideathat serum immunoreactive FSH correlates positively with themagnitude of the ovarian response should be reconsidered.     

Development and testing of a simple algorithm for a glucose clamp

The glucose clamp technique is widely used in clinical research studies to maintain a constant blood glucose (BG) level during metabolic perturbation. An algorithm is used to set the rate of an intravenous glucose infusion according to measured BG concentrations. Currently used clamp algorithms are unnecessarily complex. This paper describes the development and use of a new algorithm which is simpler to implement. The algorithm employs proportional and differential feedback control. Discrete BG sampling with a sampling period of 5 min is used. Computer simulation with a two-compartment model of glucose dynamics was used to refine the algorithm. A Monte Carlo approach was adopted to examine the effects of random variations in measured BG concentrations and the elapsed time between blood sampling and adjustment of the glucose infusion rate. A coefficient of variation in BG concentration of less than 4 per cent was predicted for a euglycemic clamp. This was confirmed when the algorithm was applied in clinical research studies. This degree of BG control compares well with other published algorithms.     

Controversies in plastic surgery: Suction-assisted lipectomy (SAL) and the hCG (human chorionic gonadotropin) protocol for obesity treatment

The advent of SAL (suction-assisted lipectomy) has dramatically increased the number of obese patients coming to our consultation offices. Despite several articles suggesting a conservative approach to fat suction, some reports insinuate that SAL might be a useful tool for obesity treatment. This hypothesis is refuted by a vast body of evidence that concludes that the adipose tissue may regenerate in adult humans. Therefore, surgical procedures are not advised as the method of choice to manage the disease. On the other hand, the terms obesity and being overweight may not be interchangeable. Obesity may be a disease whereas being overweight is asign of the disease. Consequently, proper preoperative selection of candidates for SAL becomes mandatory. The hCG (human chorionic gonadotropin) method for obesity treatment appears to be a complete program for the management of obesity. It contains pharmacologic, dietetic, and behavior modification aspects in a 40-day course of treatment. Some data suggest hCG to be lipolytic, thus explaining former clinical observations regarding body fat redistribution in treated patients. hCG commercial preparations contain -endorphin, an opioid peptide linked to mood behavior. This article speculates on the possible actions of the complex hCG -endorphin in the neuromodulation of mood and energy metabolism. The method comprises a behavior modification that helps in handling the patient better. There are some correlations between a current behavior modification program and the basic guidelines contained in the hCG protocol. Thus, the hCG method appears to be a reasonable alternative in the management of a long-standing, unsolved problem of human metabolism.     

Pharmacokinetic and pharmacodynamic study of the combination of furosemide retard and triamterene

Summary The pharmacodynamics and pharmacokinetics of the combination of furosemide retard (30 mg)/triamterene (50 mg) were compared with furosemide (30 mg) in 18 healthy male volunteers aged 39.3±6.3 years. After the administration of furosemide the onset of its effect was very rapid, reaching a maximum between 1.5 to 3 h, and followed by rebound after 9 to 10.5 h. In contrast the combination furosemide retard/triamterene showed a protracted course with a duration of effect up to 12 h. The general effect over 12 h of the two preparations was equivalent with respect to the excretion of urine, sodium, chloride and calcium, but the combination caused significantly less excretion of potassium (p0.05) than furosemide. After a lag-phase of 33.9±5.4 min the maximum plasma concentration of furosemide was reached after 3.47±0.66 h, and the elimination half-life was approximately 2 h. After a lag-phase of 33.0±17.8 min the maximum plasma concentration of the main metabolite of triamterene, the OH-TA sulphuric acid ester, was reached after 1.7±0.59 h, and its elimination half-life amounted to 1.25±0.37 h. Because of the sustained release of furosemide from the retard-formulation, its principal pharmacokinetic parameters were better adapted to those of triamterene. The consequences were not only a protracted effect but also an improved electrolyte profile, especially with regard to reduced loss of potassium. In the case of renal insufficiency, however, the potassium level in serum might be increased to an undesirable extent.     

颈痛宁主要药效学试验研究(二)

为研究颈痛宁对无菌性炎症的治疗及毒性作用。建立无菌性炎症试验动物模型。设置颈痛宁、阿斯匹林、醋酸泼尼松、生理盐水等不同对照组,采用光热辐射致痛小鼠痛阈的影响（甩尾法）和对醋酸致痛小鼠镇痛作用（扭体法）的方法进行实验。结果显示：颈痛宁对光热致痛的小鼠痛阈影响,与阿斯匹林、生理盐水比较无明显差异;颈痛宁对醋酸致痛小鼠扭体次数的影响与生理盐水比较有明显差异。说明颈痛宁对软组织无菌性炎症模型有明显的治疗舰艇一定的止痛作用;在治疗软组织损伤退变引发的颈椎病方面具有进一步研究与开发的价值。     

茶皂素为乳化剂制备黄芩苷纳米乳及其促小鼠毛发生长的药效学研究

目的 以茶皂素为天然乳化剂制备黄芩苷纳米乳（baicalin nanoemulsion,Bai-NE）,并探究其对C57BL/6小鼠毛发生长的促进作用。方法 采用超声乳化法制备Bai-NE,利用单因素实验法对Bai-NE的处方和制备工艺进行优化,并对最优处方和工艺制备的Bai-NE进行理化性质和稳定性考察。以C57BL/6小鼠为研究对象,评价Bai-NE对毛发生长的促进作用。结果 Bai-NE的最佳处方为茶皂素用量为0.5%,油相用量为5%,最佳制备工艺为超声功率180W,超声时间10min,超声次数1次。制得的Bai-NE为O/W型乳液,外观均一,平均粒径为（225.1±0.6）nm,多分散指数（polydispersity index,PDI）为0.082±0.031,载药量为1.10mg/g,pH值为7.25±0.20。稳定性结果显示,Bai-NE具有良好的离心稳定性和储存稳定性。Bai-NE能显著促进C57BL/6小鼠的毛发生长。结论 茶皂素可作为一种潜在的天然乳化剂用于Bai-NE的制备,制备的Bai-NE对C57BL/6小鼠的毛发生长有促进作用。     

Nonlinear mixed effect modeling of the pharmacodynamics of natriuretic peptides in rats

Natriuretic peptides have not only natriuretic/diuretic but also hypotensive activities, and the decreased renal perfusion caused by the excessive hypotension is known to attenuate the diuretic actions. The present study was designed to examine the relationship between the dosing (intravenous constant infusion) rates and the diuretic actions of -rat atrial natriuretic peptide (-rANP) and rat brain natriuretic peptide (rBNP) in rats, and population (nonlinear mixed effect model) analysis was applied to these complicated diuretic actions. The intrinsic diuretic activities of -rANP and rBNP could be analyzed, and the effects of blood pressure, heart rate, and also inhibition of degradation enzyme on the diuresis of natriuretic peptides were estimated simultaneously. The population analysis was useful for analyzing such pharmacodynamic data for which the individual analysis could not be applied easily.     

Pharmacokinetics and pharmacodynamics of cicaprost in healthy volunteers after oral administration of 5 to 20 μG

Summary In a Phase I study, the tolerability, pharmacodynamics and pharmacokinetics of cicaprost have been investigated in 6 male volunteers given 5, 10, 15 and 20 g as tablets of the -cyclodextrin clathrate.Individual inhibition of platelet aggregation and changes in facial colour (measured by chromametry) were dose-dependent and reached a maximum 30 to 60 min post-dose. The maximum inhibition of platelet aggregation was about 40%. After 3 to 4 h pre-treatment values had returned. Blood pressure remained within the normal range. The peak plasma level of cicaprost was reached within 15 to 90 min after drug intake. Both C_max-and AUC were individually dose-dependent. The terminal half-life in plasma of cicaprost was approx. 1 h, and its total clearance amounted to 4–7 ml·min^–1·kg^–1. The time courses of the plasma levels and of the pharmacodynamic actions were in agreement. Interindividual differences were observed in the occurrence of unwanted effects (e.g. headache).Thus, cicaprost is an orally available PGI₂-mimetic, for which effects on platelet aggregation and vascular perfusion have been demonstrated in healthy volunteers after doses of 5 to 15 g.The results will form part of the M.D. thesis of T.Staks. Some of the findings were presented at the CPT meeting, Mannheim/Heidelberg, 1989     

国产替勃龙的激素活性及药效研究

为在国内开发治疗妇女更年期与手术后绝经症的新药 ,对国产替勃龙进行了多项生殖内分泌生物实验 ,结果表明该药兼具雌激素、孕激素及雄激素活性 ,并有延迟排卵作用 ,对大鼠雌激素缺乏性阴道炎也有治疗作用。其药理特性符合临床治疗女性更年期综合症要求。