Association Between Various Drugs Used for Hypertension and Risk of Acute Myocardial Infarction

We examined the relation between various drugs used for treating high blood pressure and the incidence of acute myocardial infarction with a case-control design. Four hospitals taking care of all patients in Oslo with acute myocardial infarction participated with a total of 95 hypertensive men and women under 75 years of age who had had an acute myocardial infarction. A total of 329 age and sex matched controls were hypertensive citizens in Oslo without myocardial infarction. Frequency of treatment with drugs and odds ratio of risks with these drugs were calculated. The risk (odds ratio) of myocardial infarction for drug treatment during the last five years versus non drug treatment was 0.70 (95% confidence interval 0.42-1.18). The risk for diuretics and bT-blockers tested against no treatment was 0.91 (0.52-1.61). The corresponding risk for vasodilating drugs was 0.43 (0.20-0.91). Four weeks of exposure to aL-blockers, on the other hand, tested against other drug treatments, indicated an odds ratio of 4.62 (1.01-24.0) for individuals with a history of angina. These data confirm that treatment with diuretics and bT-blockers has only little effect on the incidence of myocardial infarction. As a whole, vasodilators are associated with a significant reduction in this incidence, but aL-blockers enhance the risk in patients with angina.     

Clinical and antimicrobial effects of a single episode of subgingival irrigation with tetracycline HCI or chlorhexidine in deep periodontal pockets

Abstract. 15 adults, each providing 4 non-adjacent untreated periodontal pockets with a probing depth (PD) exceeding 6 mm. volunteered for a randomized, split-mouth, double-blind, clinical study evaluating subgingival irrigation with chlorhexidine (CHX) or tetracycline HCl (TTC). The study protocol included oral hygiene instructions followed by scaling and root planing. Experimental and immediately adjacent teeth did not receive instrumentation. The 4 deep periodontal pockets in each patient were assigned to be irrigated with 150 ml CHX (0.12%). TTC (10 or 50 mg/ml; TTC10, TTC50), or sterile saline (control) in a single episode. Post-irrigation mechanical plaque control was supported by 2× daily CHX rinses throughout the 12-week observation interval. Recordings of oral hygiene (PlI), gingival health (GI). bleeding on probing (BoP). probing depth (PD), clinical attachment level (CAL), and microbial morphotypes from subgingival paper point samples were performed pre-irrigation. and at 1, 2, 4, 6, 8, 10, and 12 weeks post-irrigation. Mean post-irrigation PlI was low, fluctuating between 0.0 and 0.4, without significant differences between experimental groups. Mean pre-irrigation GI approximated 1.4 and reached 0.8 at the exit of study without significant differences between experimental groups. All experimental sites exhibited BoP pre-irrigation. BoP was significantly reduced in TTC50 compared to TTC10, CHX and control sites from week 8 post-irrigation. PDs were reduced for the experimental groups with TTC50 exhibiting the strongest reduction. CALs remained unaltered from pre-irrigation for TTC10. CHX and control sites over the 12-week observation interval, whereas TTC50 sites consistently improved to significantly differ from all other groups at week 10 and 12 post-irrigation. The distribution of bacterial morphotypes was significantly altered towards one of periodontal health for all experimental groups with a profound effect for TTC50 sites. Our results suggest that subgingival irrigation with TTC solutions at high concentrations may have a rôle in the management of adult periodontitis.     

视网膜缺血对兔视神经纤维损害的定量研究

目的：定量研究视网膜缺血对视神经的损害。方法：通过计算机图像分析定量测算视神经纤维数量；通过前房灌注平衡液，造成超高眼压，形成兔视网膜完全缺血模型，观察视神经纤维数量的变化。结果：正常兔眼平均视神经轴突数为１０９６０８±１４５６１（ｎ＝２２）；视网膜缺血眼视神经纤维数量明显减少（Ｐ〈０．００１）。结论：急性高眼压造成的视网膜缺血可使视神经节细胞及轴突的数量明显减少，应用计算机图像分析可定量检测这种     

OTC药评审的法律依据和程序

处方药和非处方药（Ｒｘ＆ＯＴＣ）分类管理制度是由国家法律强制作推行的药品管理制度，药品，制剂或活性成分的ＯＴＣ身分也是根据有关法规，履行法定的审批程序而确立的，我国正在酝酿的Ｒｘ＆ＯＴＣ分类管理制度对公众甚至医学从业人员都是陌生的新事物，在必要通过介绍国外现行该制度是国家的做法，了解有关ＯＴＣ药的立法及药品确立ＯＴＣ身分的合法程序，作为我国将出台的Ｒｘ＆ＯＴＣ分类管理制度的借鉴。     

Block of the endplate acetylcholine receptor channel by the sympathomimetic agents ephedrine, pseudoephedrine, and albuterol

Recent observations suggest that some patients with congenital myasthenic syndromes respond favorably to ephedrine, pseudoephedrine, or albuterol. Conventional microelectrode studies, however, provide no clear explanation for a beneficial effect of ephedrine in endplate diseases. To gain further insight into how these drugs affect neuromuscular transmission, we investigated their effects on the kinetic properties of the acetylcholine (ACh) receptor. Single channel currents were recorded from rat lumbrical muscles endplates using low concentrations of ACh and 2.5–100 μM of drugs. Between 10–100 μM, each drug progressively increased the rate of channel closure in a concentration dependent manner, consistent with an open-channel block. Albuterol acted as a sequential fast-acting channel blocker, increasing the mean burst duration in a concentration dependent manner without altering the total open time per burst or the duration of intraburst blockages. Increasing concentrations of ephedrine and pseudoephedrine also increased the number of intraburst closures but decreased the total open time per burst. None of the drugs altered single channel conductance. The channel blocking effects of ephedrine and pseudoephedrine might reduce the synaptic overactivity that occurs in the slow-channel myasthenic syndromes or in endplate ACh esterase deficiency, but these effects occur at concentrations not attainable in clinical practice.     

Otoconial alterations after embryonic development in hypergravity

The relation between prolonged hypergravity and structural adaptation of otoconia was studied in hamsters (n = 56). Three groups of hamsters (n = 27), were conceived and born in a centrifuge: group 1 (n = 10) 1 month under 2.5 G, group (2n = 9) 5 months under 2.5 G and 4 months under 1 G, group 3 (n = 8) 1 month under 2.5 G and 8 moths under 1 G. Control hamsters (n = 29) were conceived and born under 1 G (1 month old, n = 7; 9 months old, n = 22). Histological study of the otoconial layers (energy dispersive x-ray element analysis and scanning electron microscopy) showed similar calcium content, size, and shape in utricular and saccular otoconia in all groups. Different were the utricular otoconial size classes, large, medium-sized, a and small. The area with small otoconia increased in group 1 (p = 0.002). In group 2, the large otoconial area decreased (p < 0.001) and the medium-sized one increased (p < 0.001). In group 3, the large otoconial area decreased (p = 0.003) and the medium-sized one increased (p = 0.007). For age-related effects we found group 1 with an increased area of large otoconia (p = 0.001) and a decreased medium-sized one compared to groups 2 (p < 0.001) and 3 (p = 0.02). Hypergravity during formation of otoconia does not affect calcium content, size, or shape, but changes relative size of the areas with large, medium-sized, or small otoconia and the development of these areas. This resulted in a structural adaptation to hypergravity.     

反相高效液相色谱法测定血浆中氢溴酸右美沙芬浓度

本文报道采用反相高效液相色谱法测定人血浆中氢溴酸右美沙芬的浓度。采用ＹＷＧ－Ｃ１８Ｈ３７分析柱，以乙腈－水－乙酸（５０：４９：１，三乙胺调节ｐＨ至４．３）为流动相，利多卡因作内标，在２７８ｎｍ波长处监测洗提液。本法简便，灵敏，专属性好，适用于氢溴酸右美沙芬血药浓度测定及药代动力学研究 。     

Renal vein renin analysis: Limitations of its use in predicting benefit from percutaneous angioplasty

Two hundred forty-four consecutive patients (mean age 61 years), including 123 who had technically valid renal vein renin (RVR) analysis and 121 without RVR data, underwent technically successful percutaneous renal artery angioplasty (PTRA). They were retrospectively examined to evaluate the utility of RVR analysis in identifying renal hypertension (RVH), predicting benefit from PTRA, and determining if the lack of knowledge of renin levels significantly affected clinical outcome after PTRA. Abnormal RVR values were associated with clinical benefit after PTRA in 62 of 93 patients (67% sensitivity, 20% specificity, 72% positive predictive value). Clinical improvement following PTRA occurred in 31 of 37 patients with normal pre-PTRA RVR values (16% negative predictive value). RVR analysis correctly identified 86 of 117 patients with renovascular hypertension (74% sensitivity, 16% negative predictive value). Improved blood pressure (BP) control occurred in 72% with abnormal RVR analysis and 66% of the 121 patients without RVR data (p>0.1). We conclude that the very low negative predictive value significantly limited the use of RVR analysis in this elderly (mean age 60 years) patient population with a high incidence of mild renal functional impairment (mean serum creatinine 1.4 mg/dl) and bilateral renal artery stenosis (38%). The lack of pre-PTRA renin data did not significantly affect clinical outcome. If RVR data were relied upon as the exclusive selection criterion in patients of this type, many would be prevented from having the benefit of cure or improvement by PTRA.     

贵州省实施妇幼卫生项目效果分析

报道５个实施妇幼卫生项目县（市）与６个非项目县（市）妇女卫生状况的调查比较。揭示实施项目工作５年来，贵州省妇幼卫生工作取得很大进展，孕产妇死亡率由实施前２３６．８／１０万降至１４９．１／１０万。其中项目县降至９６．８／１０万，非项目县降至１８１．８／１０万。新法接生率、产前检查率与产后访视率均比项目实施前有明显提高。项目工作的实施促进了项目地区基层网络与妇幼队伍的建设，提高了基层人员妇幼卫生服务的主动性，出现了新婚女性婚姻生育观念的转变。还必须深入持久地推行孕产妇系统管理，尤其是高危孕产妇的分级管理，努力提高住院分娩率，才能大幅度降低孕产妇的死亡率