Der Oberfl?chendruck und seine Bedeutung in der klinischen Medicin

Ohne Zusammenfassung     

Ropivacaine Decreases Inflammation in Experimental Endotoxin-induced Lung Injury

Background: Endotoxin causes acute lung injury, which can lead to acute respiratory distress syndrome. Because local anesthetics are known to attenuate inflammatory reactions, ropivacaine was tested for its possible antiinflammatory effect in lipopolysaccharide-induced lung injury in rat alveolar epithelial cells (AECs) and rat pulmonary artery endothelial cells (RPAECs) in vitro and in vivo.

Methods: AECs and RPAECs were stimulated for 4 h with lipopolysaccharide or lipopolysaccharide and 1 [mu]m ropivacaine. Messenger RNA (mRNA) for intercellular adhesion molecule 1 was assessed. Isolated neutrophils were incubated with stimulated target cells to quantify adhesion and neutrophil-induced cytotoxicity in AECs and RPAECs. In vivo, lipopolysaccharide was instilled intratracheally with or without 1 mm intratracheally or intravenously administered ropivacaine. Bronchoalveolar lavage was performed 5 h later to determine neutrophil and albumin content, as well as concentrations of inflammatory mediators.

Results: In AECs and RPAECs, ropivacaine attenuated lipopolysaccharide-induced up-regulation of mRNA for intercellular adhesion molecule 1 by 41% and 24%, respectively (P < 0.05). In the presence of ropivacaine, increased neutrophil adhesion was down-regulated by 58% and 44% (P < 0.005), whereas cytotoxicity in AECs and RPAECs was diminished by 28% and 33%, respectively (P < 0.05). Enhanced neutrophil count in lipopolysaccharide lungs was reduced by 56% in the presence of intratracheally instilled ropivacaine (81% with intravenous ropivacaine; P < 0.005). Albumin was decreased by 46% with intratracheal ropivacaine (38% with intravenous ropivacaine; P < 0.05), and inflammatory mediators were decreased by 48-59% (69-81% with intravenous ropivacaine; P < 0.01).     

Effect of gallium on thein vitro formation,growth, and solubility of hydroxyapatite

Summary Gallium (Ga) is an effective treatment for the hypercalcemia of malignancy. The mechanism of action of the metal in blocking bone resorption in humans is not well understood. This paper examines the effect of Ga on thein vitro formation of hydroxyapatite (HA) in three test systems that have possible biological relevance in a pH-stat at pH 7.4, 37°C, and 0.15 M NaCl: (1) the direct precipitation of HA; (2) the transformation of amorphous calcium phosphate to HA; and (3) the growth of HA seeds. In addition, the effect of Ga on HA solubility was measured at pH 5.0, the approximate pH of osteoclastic bone resorption. Ga decreased the HA formation and/or growth kinetics in a dose-related manner in all three test systems. In addition, the time to the onset of HA formation was increased in systems 1 and 2. Also, the adsorption of Ga on the surface of HA crystals was measured. Ga reduced the dissolution kinetics of HA compared with Ga-free control. The mechanism reported herein—the significant adsorption of Ga on forming and growing HA nuclei and on the surface of HA crystals—is believed to be responsible for the effects of the metal on HA proliferation and solubility. Accumulation of the metal on newly formed metaphyseal bone can now be explained by this adsorption of Ga. Thesein vitro results partly explain thein vivo action of Ga in treating hypercalcemia by decreasing bone apatite solubility. The similarities in reducingin vitro HA formation rates of aluminum and Ga suggest that patients on long-term Ga therapy for any bone pathology should be carefully monitored for possible osteomalacic complication.     

Clinical outcome of continuous ambulatory peritoneal dialysis predicted by urea and creatinine kinetics.

The effectiveness of urea kinetics (Kt/V, where K is urea clearance, t is treatment time, and V is the volume of distribution for urea) to assess the adequacy of continuous ambulatory peritoneal dialysis (CAPD) and clinical outcome has not been established prospectively, and cross-sectional clinical studies have been inconclusive. A minimum weekly creatinine clearance of 40 to 50 L is recommended, but the adequacy of this dose is unproven. We introduced a simpler approach to creatinine kinetics in the form of an efficacy number (EN) calculated from data obtained in a standardized 4-h dwell exchange. To determine the most effective model for predicting CAPD adequacy, residual renal function, weekly Kt/V urea, weekly creatinine clearance standardized to body surface area, and EN (liters per gram of creatinine per day) were measured in 18 stable CAPD patients followed prospectively for at least 12 months. Patients were divided into three groups, good (G), intermediate (I), and poor (P), on the basis of uremic symptoms, mortality, hospital days, biochemical indices, and the need for transfer to hemodialysis. When comparing groups G (N = 6) and P (N = 8), weekly Kt/V were 2.3 +/- 0.2 versus 1.5 +/- 0.1 (P less than 0.005), weekly creatinine clearances were 71.5 +/- 8.6 versus 35.1 +/- 1.3 L (P less than 0.001), and EN were 7.4 +/- 0.8 versus 3.6 +/- 0.2 L/g of creatinine/day (P less than 0.005). Creatinine kinetics (weekly clearance and EN) but not urea kinetics could differentiate group I (N = 4) from groups G or P. Both urea and creatinine kinetics predict clinical outcome in CAPD.(ABSTRACT TRUNCATED AT 250 WORDS)     

Psychological and physiological effects of physical conditioning on the elderly

A decline in cardiovascular functioning is generally thought to occur with advancing age. The purpose of the present study was to assess the effects of regular aerobic exercise on a group of 24 young-old (65–69) and old-old (70–85 yr) volunteers. Comprehensive physiological and psychological assessments were conducted in the one week preceding the 11-week conditioning program, and in the one-week period following the conclusion of the program. The conditioning program consisted of 30 min of continuous exercise on a stationary bicycle ergometer three times weekly for 11 consecutive weeks. The results of the study document the presence of significant training effects: subjects achieved longer exercise times and increased exercise workloads. Despite these changes, however, psychological changes were generally small and nonsignificant. The present data would appear to qualify the assumption that exercise is beneficial for the elderly.     

Distribution of 14C-labelled acrylamide and betaine in foetuses of rats, rabbits, beagle dogs and miniature pigs

[14C]Acrylamide and [14C]betaine hydrochloride were administered in a single iv dose to pregnant rats, rabbits, beagle dogs and miniature pigs late in gestation (1-2 days before expected parturition). Dosages used were 10 mg/kg for rats and 5 mg/kg for the other species. The compounds were allowed to equilibrate in the animal (for 1 hr in rats and for 2 hr in the other species); the dam was then killed and the foetuses were removed by caesarean section. Each foetus was weighed and analysed for radioactivity, either by homogenization of the whole foetus (rat and rabbit) or by determining separately the radioactivity in individual organs and tissues (dog and pig). Foetal uptake of the polar compound betaine hydrochloride was much lower than that of the more lipophilic acrylamide. The sex of the foetus did not appear to affect uptake of either compound. There were no significant differences in total uptake of isotope attributable to the position of the foetus within the uterus in any of the four species given either acrylamide or betaine. Similarly, uterine position did not affect the uptake of acrylamide or betaine by individual tissues of foetal dogs or pigs. Since the distributions of 14C-labelled acrylamide and betaine hydrochloride were essentially uniform throughout a litter, it would not be necessary to sample all of the members of a litter to obtain a representative picture of foetal distribution.     

非ST段抬高型急性冠脉综合征处理的简化方法

内容：虽然目前的实践指南提供了一种处理急性冠脉综合征（acute coronary syndromes，ACS）的循证方法，但内科医师对这些证据的使用欠佳。 目标：评价和汇总有关非ST段抬高型急性冠脉综合征（non．ST—segment elevation ACS，NSTE-ACS）最佳处理方法的证据。 数据来源：于1990年1月至2004年11月的MEDLINE和Cochrane数据库系统检索经同行审稿发表的文章，并经有关专家审定。检索词包括抗血小板治疗、抗血栓形成治疗、血管紧张素转换酶抑制剂、血管紧张素受体拈抗剂、β-阻滞剂、高血压、高血脂、吸烟、饮食、糖尿病、运动、心肌缺血以及冠状动脉疾病。 研究选择和数据提取：研究选择的标准包括对照试验设计、英语以及临床相关性。数据质量以发表的杂志以及对NSTE-ACS临床处理的现实意义为准。 数据综合：尽管对照研究结果支持对NSTE-ACS患者应予综合治疗的观点，但是许多内科医师感到现行指南过于冗长、复杂。在通过危险分层确定最可能从早期介入治疗获益的患者后（与保守治疗比较），综合处理方案可由“ABCDE”四个方面构成。方案中之“A”指抗血小板治疗、抗凝血、血管紧张素转换酶抑制剂和血管紧张素受体拈抗剂；“B”指β-阻滞剂和血压控制；“C”指胆固醇治疗和戒烟；“D”指糖尿病治疗和饮食；“E”指运动。 结论：非ST段抬高型急性冠脉综合征处理的“ABCDE”方案提供了一种实用、系统地将循证医学用于临床实践的方法。     

Schädel-Hirn-Traumen im Kindes- und Jugendalter

Recommendations on the assessment of disablement in children and adolescents following craniocerebral trauma are given, with special reference to the particular situation of these age groups. The consequences of accidents causing such trauma are graded according to their relevance to later fitness for work and are displayed in a table.