Surface behavior of axolemma monolayers: Physico-chemical characterization and use as supported planar membranes for cultured Schwann cells

The axolemma membrane forms a stable and reproducible monomolecular layer at the air-aqueous interface. The major lipids and proteins are present in this monolayer in molar ratios similar to the original membrane. Acetylcholinesterase and Na-K-ATPase activities are preserved in the monolayer to levels of 64% and 25%, respectively. The total lipid fraction forms a homogeneously mixed phase. The presence of proteins in the monolayer introduces surface inhomogeneties. Among other features, this is revealed by the presence of two values of lateral pressure at which the monolayer shows partial or total collapse: a broad partial collapse at surface pressures between 13 to 30 mN/m and a sharp collapse point at 46 mN/m. The average molecular areas, the broad collapse point, and the variation of the surface potential per molecule suggest the relocation of protein components at surface pressures between 13 to 30 mN/m. The behavior is consistent with the extrusion and exposure of proteins toward the aqueous medium that depends on the lateral pressure. Schwann cells grown on coverslips coated with axolemma monolayers at 13 mN/m (beginning of the broad collapse) and 34 mN/m (above the broad collapse) recognize the difference in the surface organization of axolemma caused by the lateral pressure which affects their proliferation, morphology, and spatial pattern of organization. Our results show for the first time that response of Schwann cells depends on the intermolecular organization of the axolemma surface with which they interact. These results suggest that the local expression of putative surface molecules of axolemma that may mediate membrane recognition and the signalling of morphological and proliferative changes can be modulated by long range supramolecular properties. © 1993 Wiley-Liss, Inc.     

Granular cell tumors of the breast: A report of two cases

Granular cell tumors (GCT) are rare neoplasms, and only 173 cases of benign GCT of the breast have been documented. We report herein the cases of two patients with this tumor and discuss the methods of diagnosis and treatment. The first patient was a 60-year-old woman who presented with a firm ill-defined mass in her left breast. Mammography showed a dense shadow with spicula and skin thickness, and ultrasonography revealed a hypoechoic mass with an irregular border. Radical mastectomy was performed under the wrong preoperative diagnosis of breast cancer. The second patient was a 31-year-old woman who presented with an elastic-hard mass in her left breast. Mammography showed a well-demarcated dense mass, and ultrasonography revealed a well-defined hypoechoic mass with a large depth-width ratio. Fine-needle aspiration cytology (FNAC) showed a large number of histiocytic cells with abundant granular cytoplasm. An excisional biopsy was performed, and histological examination confirmed a diagnosis of GCT. GCT is benign, but often misdiagnosed as breast cancer both clinically and radiologically. Therefore, histological examination is essential for making a correct diagnosis, while FNAC is also useful. Local resection is still the treatment of choice, and surgeons should do their utmost to avoid performing needless radical mastectomy.     

Immunoglobulin Gene Rearrangement in Plasma Cell Dyscrasias: Detection of Small Clonal Cell Populations in Peripheral Blood and Bone Marrow

The bone marrow (BM) and peripheral blood (PB) samples of 71 patients with plasma cell dyscrasias were analysed by the Southern blot technique for the presence of clonal immunoglobulin (Ig) gene rearrangements. 53% of BM samples examined were archival material such as air dried BM slides or frozen trephine biopsies. The results were related to bone marrow plasmacytosis as determined by cytology and flow cytometry, and other clinical parameters. Clonal Ig gene rearrangements were found in BM samples of 45 (83%) of 54 MM patients and in 3 of 6 patients with monoclonal gammopathy of unknown significance (MGUS). Clonal cell populations in the PB were detected in 11 (30%) of 37 examined MM patients, but in none of the patients with MGUS or solitary plasmacytoma of bone. PB involvement was associated with progressive disease. Circulating monoclonal cells were significantly associated with higher M-protein levels (p 0.05). Thus, circulating clonal precursor cells are encountered more frequently in active MM.     

大鼠腹腔肥大细胞肿瘤坏死因子合成与释放的研究

应用免疫细胞化学技术及酶联免疫吸附试验（ELISA）对大鼠腹腔肥大细胞合成和释放肿瘤坏死因子（TNF）的状况进行了观测。结果:新鲜分离纯化的大鼠腹腔肥大细胞胞浆呈TNF蛋白阳性。单纯肥大细胞培养早期（2～4 h）,上清液中未能检测到TNF,随着培养时间延长,上清液中TNF含量增多;盐酸吗啡与肥大细胞共同培养2h时,上清液中出现可测TNF。四甲基偶氮唑盐（MTT）比色分析试验表明,肥大细胞培养上清液具体有TNF的抗肿瘤活性中。提示:大鼠腹腔肥大细胞能合成和释放TNF,盐酸吗啡能促进肥大细胞释放TNF。     

何杰金氏病增殖细胞核抗原的表达

不同时期的典型何杰金氏病１８例，用抗ＰＣ＿（１０）、Ｌ＿（２６）、ＵＣＨＬ－１抗体作ＳＰ免疫组化染色。结果显示：无一例阴性病例。ＰＣ＿（１０）阳性的ＨＲＳ细胞百分率与传统分类比较有相关性。Ｌ＿（２６）和ＵＣＨＬ＿１阳性细胞的百分率分别为１１．３％～２１．５％和３８．２％～４９．５％。表明不存在单一的Ｂ或Ｔ细胞免疫表达。提示ＨＲＳ细胞与背景中淋巴细胞之间其细胞来源有内在联系。     

细胞内钙信号的变化调节血管平滑肌细胞增殖

目的探讨细胞内钙信号的变化对大鼠血管平滑肌细胞(VSMC)增殖作用的影响及其对细胞内信号转导机制的变化。方法以培养的大鼠VSMC为模型,用雷尼丁(RY)剌激VSMC内贮Ca2 释放入胞浆,用3H亮氨酸及3H胸腺嘧啶掺入量作为反应VSMC增殖的指标,加入不同的细胞内信号转导阻断剂,观察对RY效应的影响。结果与对照组相比,RY浓度依赖性地促进细胞内游离钙浓度的增高,差异显著(P<0.05或0.01)。RY剌激组蛋白核酸合成速率明显增高,与对照组相比差异显著(P<0.01);尼卡地平(Nicardipine),蛋白激酶C抑制剂(H7),钙调素激酶(CaMPK)抑制剂(W7)和丝裂素活化蛋白激酶(MAPK)抑制剂(PD98059)能明显抑制RY介导的VSMC蛋白核酸合成速率增高,与RY剌激组相比差异显著(P<0.01)。结论细胞内钙信号的变化明显促进VSMC增殖,但其效应可能通过Ca2 、PKC、MAPK来介导。钙离子拮抗剂可抑制血管平滑肌细胞增殖。     

动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌功能监测

目的 比较静态和动态旋转系统中构建组织工程化血管模型中血管内皮细胞分泌功能。方法新型可降解材料聚羟基丁酸酯(PHB),用胶原包埋,形成多孔状PHB 胶原管形支架。分离传代、分化人脐静脉内皮细胞,接种于PHB管型支架内腔面,分别在静态、动态旋转系统中培养14 d后,测定血管内皮细胞分泌一氧化氮(NO)、前列环素(PGI2)水平。结果 在动态旋转系统构建组织工程化血管模型中血管内皮细胞分泌NO、PGI2水平显著高于静态系统,在11 d NO分别为(120.52±3.83)μmmol／L、(80.98±5.98)μmmol／L,PGI2分另9为(20.48±1.52)μg／L,(16.59±1.29)μg／L,与静态系统相比,差异有显著性(P<0.05)。结论胶原包埋PHB支架有利于细胞的黏附和生长,可作为组织工程化血管的支架材料。在动态旋转系统构建组织工程化血管模型中血管内皮细胞,具有与正常血管类似的"生理功能"。     

低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素的影响

目的探讨低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素(ADM)的影响.方法利用培养的内皮细胞株ECV-304细胞,分别与不同浓度的低密度(50 100mg/L)、氧化低密度脂蛋白(50 100mg/L)及低密度脂蛋白(50 mg/L) 氧化低密度脂蛋白(50 mg/L)进行孵育,24 h后分别收集培养上清及细胞,用放免分析检测上清及细胞内肾上腺髓质素的含量.结果低密度脂蛋白对肾上腺髓质素的分泌无影响,而氧化型低密度脂蛋白能明显刺激ADM的分泌,二者合用的作用接近于100mg/L的OX-LDL.结论OX-LDL可能具有氧化LDL使其成为OX-LDL的作用,ADM的分泌可能是对细胞损伤的一种反应.     

18F-FDG PET/CT对非小细胞肺癌区域淋巴结诊断的假阴性与假阳性研究

目的探讨18^F-FDG PET／CT在检测非小细胞肺癌（NSCLC）区域淋巴结中出现假阴性和假阳性的因素。方法随机选择手术治疗的NSCLC患者48例，术前1周内行18^F—FDG PET／CT检查，同期行CT增强扫描，术后根据病理检查结果分析PET／CT诊断NSCLC区域淋巴结转移的假阴性与假阳性因素。结果48例患者共切除区域淋巴结313枚，转移淋巴结51枚，PET／CT结果7枚假阴性。8枚假阳性，阳性预测值和阴性预测值分别为85％，97％，高于CT（57％，94％；P=0．002，0．045）。3枚假阴性淋巴结内的癌灶较小；2枚淋巴结短径约为0．4mm，小于PET／CT的空间分辨率；2枚紧邻原发灶的淋巴结，图像无法区分而视为原发灶。8枚假阳性淋巴结为患者在原发病灶基础上并发不同程度的肺部疾病和淋巴结炎症，使其糖代谢率增高。结论假阳性出于（1）淋巴结的短径小于PET／CT的空间分辨率；（2）淋巴结内的小癌灶糖代谢率较低；（3）紧邻原发灶的淋巴结与原发灶无法区分。原发肿瘤合并肺部疾病是导致PET／CT出现假阳性的重要原因。