重症肌无力的外科治疗

目的：探索重症肌无力的外科治疗方法。方法：采用胸腺切除及前纵隔淋巴清扫治疗重症肌无力35例。结果：术后早期死亡1例,34例随访2个月至5年,缓解14例,改善16例,无变化2例,死亡3例。结论;胸腺切除及前纵隔淋巴脂肪清扫治疗重症肌无力效果满意。延迟拔管或早期气管切开术,是防止术后重症肌无力危象的有效措施。胸腺肿瘤已侵及包膜或有局限性恶变的术后放疗可以减少复发,延长了生存时间。     

Cloning and characterization of the guinea pig C5a anaphylatoxin receptor: interspecies diversity among the C5a receptors

The anaphylatoxin C5a receptor (C5aR, CD88 in man) plays a prominent role in mediating inflammatory and host defense processes. Direct evidence of C5aR involvement in host defense mechanisms was demonstrated recently using C5aR knockout mice. Mice deficient in C5aR were unable to clear intrapulmonary-instilled bacteria. The guinea pig system is perhaps unique for exhibiting cross-reactivity with human complement components and its high sensitivity to anaphylatoxins. Therefore, we cloned the guinea pig C5aR from a megakaryocyte cDNA library. The deduced amino acid sequence of guinea pig C5aR is 67% identical to human, 61.6% to dog, 60.2% to mouse and 63.6% to rat C5aR. Transient expression of guinea pig C5aR in COS-7 cells and stable expression on L cell fibroblasts were confirmed by FACS analysis. Competitive binding studies using [125I]C5a and stimulation of calcium mobilization by C5a proved that functional C5aR was expressed on these stably transfected L cells. The N-terminal extracellular region of guinea pig C5aR was five to seven residues shorter than the same region in C5aR from other species and sequence homology was limited to 11%. Other outer membrane loops were also poorly conserved (8-33%) when compared across five species. Transmembrane segments were highly conserved between these various species (46-86%). Guinea pig C5aR binds human C5a, therefore residues critical for C5a binding have been conserved between these species. Sequence comparison of C5aR from multiple species permits conserved elements of the ligand binding sites to be elucidated.      

Pediatric liver transplantation. Part II. Diagnostic imaging in postoperative management

The postoperative diagnostic imaging examinations of 44 children who underwent 59 orthotopic liver transplantations were reviewed. The imaging modalities used for the evaluation of suspected complications include plain roentgenography, ultrasonography (US), computed tomography (CT), nuclear scintigraphy, arteriography, percutaneous and operative cholangiography, and endoscopic retrograde cholangiopancreatography. The main postoperative complications included ischemia, thrombosis (hepatic artery and portal vein), infarction, obstruction or leakage of the biliary anastomosis, hepatic and perihepatic infection, and allograft rejection. US, the most frequently used abdominal imaging modality, was best suited for detection of biliary duct dilatation, fluid collections in or around the transplanted liver, and hepatic arterial, inferior vena caval, and portal vein thrombosis. CT was especially helpful in corroborating findings of infection and in locating abscesses. Technetium 99m sulfur colloid (early- and late-phase imaging) provided a sensitive, although nonspecific, means of assessing allograft vascularization and morphology. Angiography showed vascularity most clearly, and cholangiography was the most useful in the assessment of bile duct patency. A diagnostic imaging algorithm is proposed for evaluation of suspected complications.     

C5a- and tumor necrosis factor-alpha-induced leukocytosis occurs independently of beta 2 integrins and L-selectin: differential effects on neutrophil adhesion molecule expression in vivo

We previously demonstrated in rabbits that various neutrophil chemotactic factors share an ability to induce recruitment of polymorphonuclear leukocytes (PMN) from bone marrow when administered intravenously (Jagels and Hugli, J Immunol 148:1119, 1992). In the study reported here, we investigated the effects of chemotactic factors on the expression of beta 2 integrins and L-selectin in vivo and the roles of these adhesionmolecules in the recruitment process. Leukocytosis was induced by infusion of either C5a (5 micrograms/kg), N- formyl-methionyl-leucyl-phenylalanine (f-MLP; 2.5 micrograms/kg), or tumor necrosis factor alpha (TNF-alpha; 100 ng/kg). C5a increased the expression of CD18 (the common subunit of beta 2 integrins) on PMN by nearly twofold and decreased levels of L-selectin by 50% within 15 minutes after administration. Levels of beta 2 integrins returned to baseline 2 to 3 hours after induction of leukocytosis. L-selectin remained depressed for more than 5 hours, demonstrating that shedding was induced in the recruited bone marrow leukocytes as well as in circulating PMN. In contrast to the response to C5a, TNF-alpha did not cause upregulation of CD18 or shedding of L-selectin. Levels of L- selectin were consistently increased 60 minutes after administration of TNF-alpha, coinciding with a rapid rise in the number of band-form PMN in the circulation. Intact IgG and F(ab)2 forms of the anti-CD18 monoclonal antibody IB4 or the anti-L-selectin antibody DREG-200 were administered intravenously 15 minutes before induction of leukocytosis by the chemotactic factors. Neither IB4 nor its F(ab)2 fragments blocked leukocytosis induced by C5a, f-MLP, or TNF-alpha. DREG-200 also did not block leukocytosis induced by f-MLP, C5a, or TNF-alpha. These results suggest that leukocyte emigration from the bone marrow into the circulation proceeds through interactions distinct from those involved in neutrophil chemotaxis and diapedesis. Shedding of L-selectin from C5a-recruited bone marrow leukocytes demonstrates activation of these cells in the recruitment process and may reflect a potential mechanism for their release. The dissimilar effects of C5a and TNF-alpha on expression of adhesion molecules may result from distinct stimulatory pathways and suggests differential activation states for cellular recruitment by these inflammatory factors.     

简化注射用头孢菌素无菌检查法的探讨

目的:完善头孢菌素类药物注射剂的无菌检验方法标准。方法:以7种不同代注射用头孢菌素为例,通过对阳性对照菌,冲洗量及青霉素酶的加入顺序等条件的选择,建立了无菌检查方法。结果:不同代头孢菌素因抗菌谱的差异,对不同验证菌株的敏感性显著不同;无菌检查法必须建立在验证试验的基础上。结论:头孢菌素无菌检查方法的验证菌株可由目前2005年版中国药典规定的5株简化为2株,并从中选择最敏感的菌株作为无菌检查中的阳性菌株,即可保证无菌检查方法的有效性。     

加替沙星微生物限度检查方法的建立

目的:完善加替沙星微生物限度检查方法。方法:采用薄膜过滤并在培养基中加入中和剂(0.1 mol·L~(-1)的硫酸锰溶液)的方法,去除加替沙星的抗菌活性。结果:本方法满足中国药典2005版验证试验的基本要求。5株验证菌株中枯草芽孢杆菌对加替沙星最敏感,可作为加替沙星微生物限度检查方法的质控菌株。结论:该方法可作为加替沙星口服制剂的常规微生物限度检查方法。     

Autonomic neuropathy and QT interval in hemodialysed patients

Abstract. Background QT interval prolongation increases the risk of ventricular arrhythmias and sudden death in diabetic autonomic neuropathy and ischemic heart disease. In end–stage renal disease (ESRD), the effects of hemodialysis on QT interval are diverse and the influence of autonomic neuropathy has yet to be clearly defined. Methods Sixty–nine ERSD patients (age 64 ± 14) were studied. Prior to the dialysis session, patients underwent four standard autonomic cardiovascular tests; before and after the dialysis session, a 12–lead ECG was recorded. Corrected QT intervals (QTc) were measured and QT dispersion (QTd) was calculated. Twelve subjects (age 59 ± 6) with normal renal function served as control group. Results Compared to controls, ESRD patients showed a longer QTc (434 ± 26 vs 414 ± 28ms; p = 0.016) and a similar QTd (35 ± 13 vs 37 ± 14ms; p = 0.54).QTc was > 440ms in 33.3% of the patients. No difference in the prevalence or score of autonomic neuropathy was observed between the subgroups with and without a prolonged QTc. After the hemodialysis session, QTc increased in 56% and decreased in 43% of the patients, and QTd increased in 45 % and decreased in 55% of the patients. QTc and QTd changes were not related to the presence of autonomic neuropathy. Conclusions A large variability in QTc and QTd response was observed after hemodialysis. Autonomic neuropathy did not contribute to QTc and QTd length, nor to QTc and QTd change after dialysis.