自体富血小板血浆对Stanford A型主动脉夹层手术中输血和短期转归的影响

目的观察自体富血小板血浆(autologous platelet-rich plasma,aPRP)对深低温停循环(deep hypothermic circulatory arrest,DHCA)下的Stanford A型主动脉夹层手术中输血量和术后短期转归的影响。方法选择2016年6月至2017年8月在本院接受手术治疗的急性Stanford A型主动脉夹层患者83例,男60例,女23例,年龄24～81岁,BMI 19.0～41.9kg/m2,ASAⅣ级。根据是否制备aPRP将患者分为观察组(n=35)和对照组(n=48)。两组患者于麻醉诱导插管后经右侧颈内静脉置入三腔中心静脉导管和Swan-Ganz导管外鞘。随后,观察组于手术开始前完成aPRP制备,对照组开始手术。记录麻醉、手术、心肺转流(cardiopulmonary bypass,CPB)、主动脉阻断和DCHA时间。记录血栓弹力图反应时间(R)、α角和最大振幅(MA);记录术中出血量和红细胞、血浆、冷沉淀和血小板用量;记录术后机械通气时间、ICU留观时间、30d内严重并发症(神经系统并发症、需要持续肾脏替代治疗的急性肾功能不全、二次插管或气管切开、胸骨后感染或胸骨愈合不良、开胸止血)发生率和死亡率。结果观察组手术时间明显短于对照组(P0.05)。麻醉、CPB、主动脉阻断时间差异无统计学意义。观察组DCHA时间明显短于对照组(P0.05)。观察组TEGα角和MA明显大于对照组(P0.05)。观察组术中红细胞、血浆和冷沉淀用量明显少于对照组(P0.05)。两组术后机械通气时间、ICU留观时间、术后30d严重并发症发生率和死亡率差异无统计学意义。结论在DCHA下的Stanford A型主动脉夹层手术,aPRP可减少术中红细胞、血浆和冷沉淀的用量,但对术后机械通气时间、ICU时间、术后30d内严重并发症发生率和死亡率无明显影响。     

Lithium augments GM-CSA generation in canine cyclic hematopoiesis

Cyclic hematopoiesis in gray collie dogs can be cured by lithium treatment. We examined the mechanism of lithium's effect by developing an assay for the canine equivalent of GM-CSF (called GM-CSA). Phytohemagglutinin (PHA)-stimulated canine blood mononuclear cells produce GM-CSA in a dose-dependent manner; this GM-CSA stimulates more neutrophil-containing colonies than does endotoxin-treated dog serum. Production of GM-CSA by PHA-stimulated normal dog cells was not altered by lithium. However, cells from gray collies during their neutrophilic period increased their GM-CSA when lithium (2 mEq/L) was added to low doses of PHA, whereas neutropenic gray collie cells did not. These data suggest that lithium could modulate cyclic hematopoiesis by increasing intramedullary GM-CSA at the time when marrow neutrophilic progenitor cells are at their nadir.     

Toxic effect of puromycin on erythrocyte membranes which is unrelated to inhibition of protein synthesis

Exposure of rabbit or human erythrocytes to concentrations of puromycin as low as 7 x 10(-4)M for 2 hr causes damage to the cell membrane, as evidenced by increased susceptibility of the cells to hyposmotic lysis, increased cell rigidity, and ultrastructural changes consistent with severe membrane damage. Puromycin causes a concentration-dependent internalization of the erythrocyte membrane, resulting in vacuolization of the cells, at concentrations between 7 x 10(-4) M and 10(-2) M. Since the erythrocyte does not synthesize protein, the data indicate that puromycin has a direct toxic effect on erythroid cell membranes which is unrelated to its action in inhibiting the synthesis of protein.     

Psychosocial stress inhibits amplitude of gonadotropin-releasing hormone pulses independent of cortisol action on the type II glucocorticoid receptor

Our laboratory has developed a paradigm of psychosocial stress (sequential layering of isolation, blindfold, and predator cues) that robustly elevates cortisol secretion and decreases LH pulse amplitude in ovariectomized ewes. This decrease in LH pulse amplitude is due, at least in part, to a reduction in pituitary responsiveness to GnRH, caused by cortisol acting via the type II glucocorticoid receptor (GR). The first experiment of the current study aimed to determine whether this layered psychosocial stress also inhibits pulsatile GnRH release into pituitary portal blood. The stress paradigm significantly reduced GnRH pulse amplitude compared with nonstressed ovariectomized ewes. The second experiment tested if this stress-induced decrease in GnRH pulse amplitude is mediated by cortisol action on the type II GR. Ovariectomized ewes were allocated to three groups: nonstress control, stress, and stress plus the type II GR antagonist RU486. The layered psychosocial stress paradigm decreased GnRH and LH pulse amplitude compared with nonstress controls. Importantly, the stress also lowered GnRH pulse amplitude to a comparable extent in ewes in which cortisol action via the type II GR was antagonized. Therefore, we conclude that psychosocial stress reduces the amplitude of GnRH pulses independent of cortisol action on the type II GR. The present findings, combined with our recent observations, suggest that the mechanisms by which psychosocial stress inhibits reproductive neuroendocrine activity at the hypothalamic and pituitary levels are fundamentally different.     

浅谈分子筛制氧系统的选择使用和管理

本文论述了分子筛制氧机的工作原理、主要组成部分及作用.强调了应严格遵守规章制度,认真做好制氧机的维护保养,加强质量监控和管理.同时阐述了医院在选购制氧系统时要综合分析影响其能耗的因素,在保证氧气产量和纯度的前提下,尽量降低系统能耗,提高长期运行的经济效益.     

Bench-to-bedside review: Hyperinsulinaemia/euglycaemia therapy in the management of overdose of calcium-channel blockers

Hyperinsulinaemia/euglycaemia therapy (HIET) consists of the infusion of high-dose regular insulin (usually 0.5 to 1 IU/kg per hour) combined with glucose to maintain euglycaemia. HIET has been proposed as an adjunctive approach in the management of overdose of calcium-channel blockers (CCBs). Indeed, experimental data and clinical experience, although limited, suggest that it could be superior to conventional pharmacological treatments including calcium salts, adrenaline (epinephrine) or glucagon. This paper reviews the patho-physiological principles underlying HIET. Insulin administration seems to allow the switch of the cell metabolism from fatty acids to carbohydrates that is required in stress conditions, especially in the myocardium and vascular smooth muscle, resulting in an improvement in cardiac contractility and restored peripheral resistances. Studies in experimental verapamil poisoning in dogs have shown that HIET significantly improves metabolism, haemodynamics and survival in comparison with conventional therapies. Clinical experience currently consists only of a few isolated cases or short series in which the administration of HIET substantially improved cardiovascular conditions in life-threatening CCB poisonings, allowing the progressive discontinuation of vasoactive agents. While we await further well-designed clinical trials, some rational recommendations are made about the use of HIET in severe CBB overdose. Although the mechanism of action is less well understood in this condition, some experimental data suggesting a potential benefit of HIET in β-adrenergic blocker toxicity are discussed; clinical data are currently lacking.     

Hepatic portoenterostomy for biliary atresia. A comparative study of histology and prognosis after surgery

Specimens of excised tissue from the porta hepatis in 26 infants with extrahepatic biliary atresia undergoing hepatic portoenterostomy were analysed histologically for the presence and size of biliary ductules. No correlation could be found between the establishment of effective biliary drainage and the number or size of biliary ductules. it is suggested that prognosis after surgery may be related to the intrahepatic lesion and age of the child at operation rather than to the histology of the extrahepatic bile duct remnants.     

Effect of oral and inhaled salbutamol in infants with bronchiolitis

The response of bronchiolitis to bronchodilator drugs is controversial. The present study was designed to evaluate the efficacy of oral or metered dose inhaler (MDI) salbutamol using a coffee cup as a spacer device in bronchiolitis. In the trial, 31 hospitalized patients between 6 and 24 months of age, who exhibited the first episode of acute bronchiolitis without any other predisposing illness such as cystic fibrosis, congenital heart disease etc., were randomly assigned to receive oral salbutamol (n=11, 0.1 mg/kg per dose, four times a day), or MDI salbutamol (n = 12, 200 μg per dose, every 3 h) or formed the control group without any bronchodilator therapy (n = 8). All of the patients were given supplemental oxygen as needed and adequate hydration was maintained. The patients were evaluated with clinical symptom scores. There were no differences in the beneficial or side effects of salbutamol, or the number of days in hospital between the treatment groups and the control group. It was concluded that there is no beneficial effect in using bronchodilators in infants with bronchiolitis. Supplemental oxygen and maintenance of normal hydration may be adequate.     

Applicability of LDLR flanking microsatellite polymorphisms for prenatal diagnosis of homozygous state for familial hypercholesterolemia

Analysis of newly identified microsatellite polymorphisms flanking the low density lipoprotein receptor (LDLR) gene was undertaken in the kindred of a child with apparent homozygous LDLR deficiency. The applicability of these approaches to prenatal diagnosis is considered and compared with previous approaches applying functional studies of the LDLR in amniotic fibroblasts.