一项新的水质检验——可同化有机碳测定

可同化有机碳(AOC)是一项新的水质检测指标,通过它可以评估供水系统的水中是否有足够的营养物质可使微生物再生长。由于目前尚无可行的化学方法检测 AOC,因此主要是用各种生物方法加以检测。本文介绍用荧光假单胞菌 P—17菌株和螺菌属 NOX 菌株作为测试菌,通过定量观察其在水样中的生长,如从接种到生长至最大数量,以考察其利用水中营养物质的情况,进而推算出水中 AOC 的浓度。     

糖皮质激素联合抗凝在急性/亚急性重症颅内静脉血栓治疗中的探索

目的 本研究初步探讨糖皮质激素联合抗凝治疗在急性/亚急性重症颅内静脉血栓(cerebral venous thrombosis, CVT)中的作用。方法 纳入10例经过糖皮质激素联合抗凝治疗的急性/亚急性重症CVT患者,对治疗前后及出院3个月时的神经功能缺损、颅内压增高情况和血清、脑脊液炎症指标及不良事件进行回顾性分析。结果 10例患者经过糖皮质激素冲击治疗后2周,与入院时基线值相比,血清中性粒细胞与淋巴细胞比值(neutrophil-to-lymphocyte ratio, NLR)(P<0.05),超敏C反应蛋白(hypersensitive C-reactive protein, hs-CRP)(P<0.01),白细胞介素-6(interleukin 6,IL-6)(P<0.01)和脑脊液IL-6浓度(P<0.01)均明显下降;与入院时基线值相比,出院时改良Rankin量表(modified Rankin Scale, mRS)评分(P<0.01)、美国国立卫生研究院卒中评分(National Institutes of Health Stroke ...     

Primary tumors of the spine. Initial oncologic aspects: epidemiology, anatomo-prognostic and therapeutic classification

Primary tumors of the vertebral column are rare: 20 per cent of all primary tumors of the spinal column. The distribution by type of tumor shows that the three most frequent primary tumors considered to be "radio and/or chemo resistant lesions" are the chordoma (15.5 to 24.5%), the chondrosarcoma (20%) and the giant cell tumor (10%). A second group with "chemo and/or radiosensitive lesions" include the Ewing sarcoma, primary lymphoma and plasmocytoma (5%). We consider a third group with the benign tumor: osteochondroma, chondroma, osteoid osteoma, osteoblastoma, aneurysmal bone cyst, hemangioma and eosinophilic granuloma (2 to 3%). The last tumoral group agrees with sarcomatous tumors: osteogenic sarcoma, fibrosarcoma, malignant fibro-histiocytoma, angiosarcoma and hemangio-pericytoma (1 to 3% of primary tumors of the vertebral column); they are most frequently secondary to Paget's disease, giant cell tumor or to radiation therapy and their prognosis is poor.     

Overexpression of S100A4 is closely related to the aggressiveness of gastric cancer

Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea.     

Molecular evolution of human immunodeficiency virus type 1 subtype A in Senegal: 1988-1997

OBJECTIVE: Few studies have been able to track the genetic diversity of HIV-1 viruses in human populations over time. We analyzed the molecular evolution of subtype A over a 10-year period, in a cohort of female sex workers with a known time of infection. STUDY DESIGN/METHODS: We amplified and sequenced the C2-V3 region of the surface envelope glycoprotein from 73 HIV-1-infected women, infected between 1987-1997. RESULTS: Fifty-one patients were infected by subtype A viruses. The viruses demonstrated significant diversification (p < 0.001) with mean genetic distance increasing from 8.6% in 1989 to 15.9% in 1997. The slope of the fitted curve suggested a rate of diversification of 0.7% per year. The majority of subtype A viruses clustered with HIV-1 subtype A/G recombinant form (IbNG). CONCLUSION: The genetic diversity of HIV-1 subtype A infections doubled over the first 10 years of this high risk population's epidemic, suggesting that implementation of vaccines early in the epidemic may have a higher likelihood of success based on levels of genetic diversity. The A/G recombinant form (IbNG) has taken epidemic proportions in West Africa. This is of particular importance in understanding the epidemiology of HIV-1 subtypes in Africa and to further dissect the potential phenotypic and biological characteristics of these viruses.     

逆转录病毒介导的人促红细胞生成素基因在淋巴细胞中的表达

本实验设计和构建了人促红细胞生成素（Epo）重组逆转录病毒载体（LXSN-Epo）,载体中小鼠白血病病毒长末端调控序列翻译调控人Epo基因的表达。通过重组逆转录病毒,将Epo基因转导到大鼠T和B淋巴细胞中,DNA-PCR分析证明带有人Epo基因的逆转录病毒已整合到T和B淋巴细胞基因中,RT-PCR分析显示了在两种细胞中均表达了 Epo mRNA。体外生物学活性测定显示,在转导的T淋巴细胞培养上清中Epo表达水平高达243mU/ml,在感染的B淋巴细胞培养上清中Epo活性达43mU/ml。在感染的B细胞中,Epo表达在mRNA和蛋白水平均证明了逆转录病毒能有效地和迅速地转导Epo基因到新培养的B细胞中,而不需要药物选择。这些研究开始了逆转录病毒介导的基因转移走向体内Epo基因治疗研究的过程。     

Organisation anatomique et physiologique des activités motrices de la moelle épinière

Résumé La moelle épinière utilise deux grandes modalités fonctionnelles: l'activité réflexe et l'activité programmée.L'activité réflexe constitute la modalité la plus anciennement connue, elle englobe de nombreux arcs réflexes imprégnés de finalités fort diverses. Ainsi le réflexe myotatique, arc monosynaptique le plus simple, maintient et protège le tonus musculaire; les réflexes à point de départ cutané, polysynaptiques, impliquant des réseaux interneuronaux, extériorisent des réponses motrices de défense et de protection indiquant déjà une compétence plus intégrative.L'activité programmée médullaire est supportée par des circuits neuronaux assez solidement fixés. Cette organisation fonctionnelle produit des séquences motrices correctement agencées dans l'espace et dans le temps (locomotion, miction, défécation, réflexes sexuels).Aces deux modalités basales viennent se superposer les influences supra-spinales à capacité exécutoire. Ces signaux, canalisés vers la voie finale commune, agissent, dans une faible part, directement sur les motoneurones spinaux et, en effet, dans une très large mesure, ils utilisent les circuits interneuronaux et modulent ou déclenchent réflexes et programmes médullaires engendrant ainsi une activité cinétique cohérente.     

Mutational analysis of Fas ligand gene in human non-Hodgkin lymphoma

Among the systems triggering apoptosis, the Fas-Fas ligand (FasL) system is recognized as a major pathway for the induction of apoptosis in cells and tissues. Ligation of Fas by either an agonistic antibody or FasL transmits a 'death signal' to the target cell, potentially triggering apoptosis. Alterations of genes along the Fas-mediated apoptosis pathway have been reported in many human cancers. However, there have been no data regarding FasL gene mutations in human cancers. We hypothesized that FasL gene mutation might be involved in the development of non-Hodgkin lymphoma (NHL). In this study, we analyzed the entire coding region of the FasL gene for the detection of somatic mutations in a series of 111 NHLs and found that one tumor had a FasL gene mutation in the cytoplasmic domain. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant in 293T cells, but couldn't find any significant loss of cell death compared to the wild-type FasL. Together, these data suggest that FasL is occasionally mutated in human NHL and that FasL mutations appear to play no role in the pathogenesis of the vast majority of NHLs.     

102T/C polymorphism of serotonin receptor type 2A gene is not associated with schizophrenia in either Chinese or British populations

Several pieces of evidence implicate serotonin receptors in the aetiology of schizophrenia, and recently a number of studies have reported a genetic association between the 102T/C polymorphism of serotonin receptor type 2A gene and schizophrenia. Unfortunately a number of failures to replicate these positive associations in both Caucasian and Chinese populations have also been reported. We have examined the 102T/C polymorphism by PCR amplification and restriction analysis of DNA from: 202 schizophrenics and 202 controls from Shanghai; 112 schizophrenics and 224 parents from Chengdu, Cina; and 253 schizophrenics and 244 controls from the the UK. We find no evidence of association or transmission disequilibrium between the 102T/C polymorphism and schizophrenia in any of the groups we have examined. We conclude that either the original positive reports occurred by chance or any effect must be minimal, and urge caution in interpreting small positive results derived using data from different centres.