Prostacyclin production in vitro by rabbit aortic endothelium: correction for unstirred diffusional layers

The degree of mixing in fluid layers immediately adjacent to the endothelial surface is a major variable in assessment of prostacyclin (PGI2) production by cultured endothelial cells or intact vessel endothelium in vitro. Lack of adequate mixing should lead to underestimation of true production because PGI2 immediately adjacent to endothelium would be only poorly sampled upon buffer collection. Thoracic aortas from 38 New Zealand white rabbits were therefore excised, opened longitudinally, and mounted endothelial side uppermost in a buffer-filled chamber which excluded cut tissue edges from study. Production of PGI2 under unstirred and magnetically stirred conditions was measured by radioimmunoassay (RIA) for 6-keto-PGF1 alpha. For animals pretreated with the combination of papaverine and heparin (see below), unstimulated and arachidonate-stimulated 6-keto-PGF1 alpha increased with stirring rate toward limits of 2.9 and 28.5 ng/cm2/min, respectively. Unstimulated and stimulated 6-keto PGF1 alpha measured at 650 rpm, for example, were greater than their values at 0 rpm by factors of 3.5 (2P less than .01) and 3.7 (2P less than .001), respectively. The process of vessel excision, however, produces another variable: degree of injury to endothelium caused by such factors as secondary vessel contraction and thrombin generation. Vessel contraction and thrombin generation can be minimized, respectively, by the use of a smooth muscle relaxant and heparin administered prior to killing of the animals. The rabbits were, therefore, grouped according to intravenous (IV) treatment, prior to killing, with saline, papaverine (4 mg/kg), heparin (200 U/kg) or the combination of papaverine and heparin (same doses). As compared with pretreatment with saline, papaverine alone, or heparin alone, pretreatment with the combination of papaverine and saline led to increases in stimulated 6- keto-PGF1 alpha of 1.6- to 2.8-fold. By transmission electron microscopy, endothelium from animals pretreated with saline showed ultrastructural changes, including disruption of cytoplasm, separation without detachment of most endothelial cells from subendothelium, and focal areas of denudation. In contrast, ultrastructural integrity of endothelium was preserved in aortas of animals pretreated with combined papaverine and heparin. These results support the hypothesis that unstirred diffusional layers lead, in vitro, to underestimation of PGI2 production, especially when vessels are protected from excisional injury.(ABSTRACT TRUNCATED AT 400 WORDS)     

Vitamin D attenuates proteinuria by inhibition of heparanase expression in the podocyte

The glomerular filtration barrier consists of podocytes, the glomerular basement membrane, and endothelial cells covered with a glycocalyx. Heparan sulphate (HS) in the glomerular filtration barrier is reduced in patients with proteinuria, which is associated with increased expression of the HS‐degrading enzyme heparanase. Previously, we showed that heparanase is essential for the development of proteinuria in experimental diabetic nephropathy. Vitamin D supplementation reduces podocyte loss and proteinuria in vitro and in vivo. Therefore, we hypothesize that vitamin D reduces proteinuria by reducing glomerular heparanase. Adriamycin‐exposed rats developed proteinuria and showed increased heparanase expression, which was reduced by 1,25‐dihydroxyvitamin D₃ (1,25‐D₃) treatment. In vitro, adriamycin increased heparanase mRNA in the podocyte, which could be corrected by 1,25‐D₃ treatment. In addition, 1,25‐D₃ treatment reduced transendothelial albumin passage after adriamycin stimulation. In line with these results, we showed direct binding of the vitamin D receptor to the heparanase promoter, and 1,25‐D₃ dose‐dependently reduced heparanase promoter activity. Finally, 1,25‐D₃‐deficient 25‐hydroxy‐1α‐hydroxylase knockout mice developed proteinuria and showed increased heparanase, which was normalized by 1,25‐D₃ treatment. Our data suggest that the protective effect of vitamin D on the development of proteinuria is mediated by inhibiting heparanase expression in the podocyte. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Monoclonal antibody 7G3 recognizes the N-terminal domain of the human interleukin-3 (IL-3) receptor alpha-chain and functions as a specific IL-3 receptor antagonist

The human interleukin-3 receptor (IL-3R) is expressed on myeloid, lymphoid, and vascular endothelial cells, where it transduces IL-3- dependent signals leading to cell activation. Although IL-3R activation may play a role in hematopoiesis and immunity, its aberrant expression or excessive stimulation may contribute to pathologic conditions such as leukemia, lymphoma, and allergic reactions. We describe here the generation and characterization of a monoclonal antibody (MoAb), 7G3, which specifically binds to the IL-3R alpha-chain and completely abolishes its function. MoAb 7G3 immunoprecipitated and recognized in Western blots the IL-3R alpha-chain expressed by transfected cells and bound to primary cells expressing IL-3R alpha. MoAb 7G3 bound the IL-3R alpha-chain with a kd of 900 pmol/L and inhibited 125I-IL-3 binding to high- and low-affinity receptors in a dose-dependent manner. Conversely, IL-3 but not granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibited 125I-7G3 binding to high- and low-affinity IL- 3Rs, indicating that MoAb 7G3 and IL-3 bind to common or adjacent sites. In keeping with the inhibition of IL-3 binding, MoAb 7G3 antagonized IL-3 biologic activities, namely stimulation of TF-1 cell proliferation, basophil histamine release, and IL-6 and IL-8 secretion from human endothelial cells. Two other anti-IL-3R alpha-chain MoAbs failed to inhibit IL-3 binding or function. Epitope mapping experiments using truncated IL-3R alpha-chain mutants and IL-3R alpha/GM-CSFR alpha chimeras revealed that 31 amino acids in the N-terminus of IL-3R alpha were required for MoAb 7G3 binding. MoAb 7G3 may be of clinical significance for antagonizing IL-3 in pathologic conditions such as some myeloid leukemias, follicular B-cell lymphoma, and allergy. Furthermore, these results implicate the N-terminal domain of IL-3R alpha in IL-3 binding. Since this domain is unique to the IL-3/GM- CSF/IL-5 receptor subfamily, it may represent a novel and common binding feature in these receptors.     

Biliary and portal vein strictures following treatment of Hodgkin’s lymphoma

Treatment of abdominal lymphoma can be associated with bowel stricture or perforation. Rarely, the common bile duct or portal vein can be involved. This is the first case of stricture formation of both the portal vein and common bile duct in a patient following successful treatment of lymphoma. The development of extensive hilar varices rendered surgical management high risk. A staged approach to treatment was used. First, a percutaneous portal vein stent was placed, resulting in resolution of the hilar varices. This was followed by a surgical hepaticojejunostomy, performed without complication. Gastrointestinal complications are rare following treatment of lymphoma but may affect a variety of sites. The safe and effective treatment of this case highlights the benefit of a multidisciplinary approach to complex medical and surgical problems.     

计算机辅助的EBRA-FCA法分析半髋表面置换治疗股骨头缺血性坏死假体生物力学变化

背景:对于中晚期(FicatⅢ,Ⅳ期)股骨头缺血性坏死且髋臼基本完好的患者,单纯股骨头表面置换是一种较好的治疗方法。股骨假体位置、下沉影响全髋关节置换术的治疗效果,但假体位置、下沉对半髋表面置换术疗效的影响尚需进一步研究。目的:观察钴铬合金半髋表面置换对中晚期(FicatⅢ,Ⅳ期)股骨头缺血性坏死且髋臼基本完好患者髋关节功能的影响,并分析疗效与股骨假体柄干角、下沉的关系,评估计算机辅助X射平片分析对假体失败的预测价值。设计:病例分析。单位:广西医科大学第一附属医院脊柱骨病科。对象:选择1997-06/2002-07广西医科大学第一附属医院脊柱骨病科收治的中晚期(FicatⅢ,Ⅳ期)股骨头缺血性坏死行半髋表面置换患者41例(48髋),患者手术时的年龄29～49岁,平均(37±9)岁,其中男30例,女11例。其中FicatⅢ期35髋,FicatⅣ期13髋,髋臼均相对正常。所有患者病变部位病理检查均为股骨头缺血性坏死;且均签署知情同意书。方法:①于术前和随访时采用UCLA(UniversityofCaliforniaLosAnge-les)髋关节功能评分标准对患者手术前后疼痛、步行、功能、活动进行评分,每一项记分为1～10分,10分为最佳。优,35～40分,好29～34分,一般22～28分,差<22分。术后评分为随访时评分平均值。②运用计算机辅助的EBRA-FCA法,在术后骨盆的X射线平片上测量股骨假体的柄干角、下沉,并对半髋表面置换术治疗股骨头缺血性坏死的疗效与股骨假体的柄干角、下沉的关系进行分析。③采用复诊的方式进行随访,于术后2个月开始第1次随访,每年随访1次,共随访8年。④两组样本间均数比较采用独立样本t检验(并做方差齐性检验)。在对临床结果的析因分析(posthocanalysis)基础上,比值比(oddsratio)分析用来确定假体早期失败的相对危险性。主要观察指标:①纳入患者半髋表面置换术前后UCLA评分比较。②FicatⅢ期和Ⅳ期患者术后疗效比较。③不同疗效患者随访期间股骨假体柄干角和下沉程度比较。结果:全部病例均获随访,其中8例随访3年,8例随访4年,8例随访5年,7例随访6年,6例随访7年,4例8年。①UCLA髋关节功能评分:疼痛、步行、功能、活动评分别由术前的(3.1±1.2),(4.4±1.7),(5.8±2.3),(5.5±2.7)分提高到术后的(9.1±2.5),(9.2±2.9),(9.1±3.4),(7.1±3.1)分,差异明显(P<0.01)。②疗效:FicatⅢ期35髋术后的满意率为89%与FicatⅣ期13髋术后的满意率相近(69%,P>0.05),其中疗效差8髋为失败组,其余40髋为成功组。③计算机辅助的X射线平片检查结果:失败组6个髋的股骨假体有明显下沉(其柄干角小于130°),2个髋的髋臼有破坏(1个柄干角为128°,1个柄干角为136°)。成功组平均柄干角明显大于失败组,分别为139°±6.2°,127°±5.3°,差异明显(P<0.01)。失败组中,6髋假体头中心和假体柄尖的下沉分别为(5.02±1.3)mm和(4.85±1.1)mm明显大于成功组[(1.48±0.2)和(1.04±0.2)mm,P<0.05];小于130°的柄干角其发生不良后果的机会增加了7.1倍。④股骨假体下沉时间:计算机辅助的X线片分析显示股骨假体下沉超过2mm的时间为(19.5±3.2)个月,明显早于临床出现症状的时间和X射线平片异常的时间[(35.6±4.2),(24.8±2.5)个月,P<0.01]。结论:①钴铬合金半髋表面置换是一种可供选择的向全髋关节置换术过渡的较好的治疗方法,可以恢复中晚期(FicatⅢ,Ⅳ期)股骨头缺血性坏死的且髋臼基本完好的患者的髋关节功能。②假体的松动下沉与假体的位置有关。③用来评估假体柄在骨盆平片上的下沉程度的计算机辅助的平片分析可以预测假体的失败。     

The effect of an intraoperative treatment algorithm on physicians' transfusion practice in cardiac surgery

Background : Inappropriate transfusion in cardiac surgery may, in part, be due to empiric transfusion therapy instituted in the absence of timely laboratory data. Therefore, the effect of a transfusion decision algorithm based on intraoperative coagulation monitoring of physicians' transfusion practice and the transfusion outcome was evaluated. Study Design and Methods : In a randomized, controlled trial, cardiac surgical patients determined to have microvascular bleeding at the cessation of cardiopulmonary bypass were assigned to algorithm (A) or standard (S) therapy. Group A was treated with plasma and platelet therapy according to a transfusion algorithm based on on-site coagulation data available within 4 minutes. For Group S, the use of laboratory-based data and the decision to transfuse blood components were at physician discretion. Results : Sixty-six patients were entered into the study (Group A, n = 30; Group S, n = 36). Other than the fact that there were significantly more female patients in Group S than in Group A, no differences between cohorts in regard to perioperative risk factors for blood transfusion needs were identified. Therefore, gender was factored in as a covariate in the statistical analysis. Group A patients received fewer hemostatic blood component units (p = 0.008) and had fewer total donor exposures (p = 0.007) during the entire hospitalization period. Linear regression analysis of the differences in slopes in Groups A and S for the relationships between the red cell volume lost and the red cell volume transfused (p < 0.03), non-red cell units transfused (p < 0.0001), and total number of blood components transfused (p < 0.0001) demonstrated that physicians' transfusion practice was significantly altered by the use of a transfusion algorithm with on-site coagulation data, independent of surgical blood losses. Conclusion : The use of algorithms by transfusion decision makers can serve as an effective physician education intervention.     

Rapid freezing of whole blood or buffy coat samples for polymerase chain reaction and cell culture analysis: application to detection of human immunodeficiency virus in blood donor and recipient repositories. The Transfusion Safety Study Group

Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens.     

石斛类叶鞘的显微鉴定研究

商品石斛的植物来源复杂,规格繁多,外形鉴定较困难。为了准确鉴定石斛的品种,对常作为药用的16种石斛属(Dendrobium Sw)植物的叶鞘进行了显微观察,发现其表皮细胞的形状,大小,所含草酸钙结晶的形状、大小、分布等种间区别较明显,可作为鉴别石斛种类的科学依据之一。本文对金钗石斛D.nobile Lindl。等16种石斛的叶鞘表面特征加以描述,并附主要特征图和检索表。     

盐酸普鲁卡因经皮离子导入的研究

目的：考察盐酸普鲁卡因的离子导入与电流强度、药物浓度的关系。方法：测定不同的电流强度、不同的药物浓度的离子导入增渗倍数（ＥＲ）。结果：固定药物浓度,电流强度为０．１,０．２和０．３ｍＡ时的ＥＲ值分别为６８．９９和１２７。固定电流强度０．２ｍＡ,药物浓度为０．０１５１,０．０３０４和０．０６０５ｇ／１００ｍｌ时的ＥＲ值分别为９５,９９和９８,结论：离子导入可以显著提高药物渗透速率,增渗倍数（ＥＲ）随     

L -粘附素单抗在缺血再灌注损伤中的作用

目的中性粒细胞粘附在缺血再灌注损伤中有非常重要的作用.本文用SD大鼠趾长屈肌缺血再灌注损伤模型,观察L-粘附素单抗LAM1-116在缺血再灌注损伤中的作用.方法30只SD大鼠被均分为2组LAM1-116组和生理盐水对照组.每只大鼠的一侧趾长屈肌作为正常对照,另外一侧进行3 h缺血4 h再灌注.结果LAM1-116组实验侧的髓过氧化物酶为正常的2倍(2.3±2.2),生理盐水对照组则为正常的28倍(27.5±11.7)(P＜0.001);LAM1-116组的湿重比(1.10±0.10)、疲劳肌力(77.1%±12.1%)与对照组相比(分别为1.23±0.10和49.7%±9.3%)明显改善(P＜0.05);组织学上,LAM 1-116组的中性粒细胞局部浸润显著减少,水肿减轻.结论通过L-粘附索单克隆抗体LAM1-116阻断L-粘附素的功能,可以有效地降低中性粒细胞在再灌注肌肉中的浸润,防止组织水肿,从而改善肌肉的功能.