A prospective study to identify the risk factors associated with acute reactions to platelet and red cell transfusions

It is generally assumed that febrile nonhemolytic transfusion reactions are an immunologically mediated reaction involving the recipient's plasma and the white cells in the donor unit. This has led to the use of white cell reduction and pretransfusion medication, to try to minimize these reactions. To better understand febrile transfusion reactions, a prospective study was performed in which all patients receiving platelet and red cell transfusions in a tertiary-care medical center were interviewed before and after transfusion to obtain information about the typical presentation of the syndrome. It was found that transfusion reactions were much more frequently associated with platelet transfusion (30.8%) than with red cell transfusion (6.8%, p < 0.0005). The routine use of antipyretics prevented most episodes of fever but did not prevent the occurrence of other symptoms such as chills, cold, and discomfort. The application of logistic regression analysis revealed that the dominant factor determining the risk of a reaction was not white cell contamination, but the age of the component (p < 0.005). The significant relationship between reaction and the increasing age of the component suggests that cytokines released in the component during storage may be responsible for many reactions to blood components.     

乙酰丹酚酸A对血小板功能的影响

乙酰丹酚酸以A(ASAA)是丹参有效成分衍生物。体外实验表明,ASAA对ADP、胶原、AA和凝血酶诱导的大鼠和兔血小板聚集有明显抑制作用。在半体内实验中,ASAA对多种诱导剂所致血小板聚集也有显著抑制作用,且持续时间达2h以上。此外,在抑制血小板聚集的同时,ASAA对胶原诱导的血小板5-HT释放也有显著抑制作用。上述结果提示,ASAA可能是一作用广泛的血小板功能抑制剂。     

AIRWAY OBSTRUCTION IN CHILDREN

Seventeen children presenting with airway obstruction have been studied to highlight the similar clinical features of different etiological conditions, their diagnostic limitations, and the importance of early bronchoscopy. There were 8 patients with foreign body in lower airway, out of which 6 were vegetable foreign bodies. Few rarer conditions like membranous laryngotracheobronchitis, subglottic hemangioma and acyanotic congenital heart disease producing airway obstruction have been highlighted. There were 2 deaths in the study unrelated to endoscopic procedure.KEY WORDS: Airway obstruction, Bronchoscopy     

金艾康合并化学药物治疗肿瘤临床疗效观察

目的：探讨金艾康（汉防己甲素片）合用化学药物治疗肿瘤的临床增效作用。方法：通过比较治疗组与对照组（金艾康合并化学药物者为治疗组,单用化学药物者为对照组,每组各为３０例）的总缓解率与毒副反应来评价金艾康对化疗药物的增效作用。结果：治疗组与对照组的总缓解率分别为８０％与６６．７％,其中部分毒副反应如消化道反应与肢端订木症状等治疗组明显低于对照组。结论：金艾康具有对化学药物治疗肿瘤增效作用,其作用机理可     

Switch movements and the myosin crossbridge stroke

The myosin II motor from Dictyostelium discoideum has been engineered to contain single tryptophan residues at strategic locations to probe movements of switch 1 and switch 2. The tryptophan residue at W501 probes movement of the relay helix and indirectly reports on switch 2 movement. This probe suggests that there is an equilibrium between the switch 2 open- and closed-states when the γ-phosphate position is occupied. Actin does not appear to greatly affect this equilibrium directly, but has indirect influence via switch 1. The latter region has been probed by introducing tryptophan residues at positions 239 and 242. The kinetics of the actomyosin ATPase in solution is discussed with respect to recent crossbridge models based on high-resolution crystal structures. To whom correspondence should be addressed: Tel.: +44-(0)-116-229-7048; Fax: +44-(0)-116-229-7018; E-mail: crb5@le.ac.uk