Expression of the Human Immunoglobulin Heavy Chain VH6 Gene Element by Fetal B Lymphocytes

Fetal B lymphocytes in mice and humans use a limited number of the available V_H gene segments. Mouse fetal B cells primarily utilize 3' V_H elements, suggesting that the localization of these elements determines their rearrangement frequency. The previously reported non-random usage of human V_H genes has been more difficult to explain. In this study the authors analysed the expression of the most proximal 3' human V_H element (V_H6) using a monoclonal antibody (JE-6). V_H6 expression was assessed in various B cell differentiation stages from fetal liver, bone marrow and spleen at 12–20 weeks of gestation. The authors demonstrate that the level of V_H6 expression does not exceed a stochastic usage frequency. This suggests that the localization of V_H6 does not significantly promote its expression during human fetal life, and that other factors must affect the usage of V_H genes during human fetal development.     

结肠腺瘤与腺癌p53,c—erbB2蛋白及CEA的表达和意义

应用免疫组化法检测１５例正常结肠粘膜，４０例结肠瘤及４０例结肠癌组织的ｐ５３，ｃ－ｅｒｂＢ２和ＣＥＡ的表达。结果发现：结肠癌患者ｐ５３，ｃ－ｅｒｂＢ２及ＣＥＡ的阳性表达率均显著高于腺瘤（Ｐ〈０．０１）。ｐ５３阳性表达在不典型增生腺瘤患者中，重度显著高于轻度病例（Ｐ〈０．０１）；在结肠腺癌患者中低分化显著高于高分化病例（Ｐ〈０．０５）；ＣＥＡ的新型单克隆抗体ｃｏｌ－１对结肠癌的敏感性和特异性均高，阳     

A novel two-step method for the formation of tissue-engineered cartilage by mature bovine chondrocytes: the alginate-recovered-chondrocyte (ARC) method.

Most attempts to tissue-engineer cartilage have involved seeding of cultured cells into a biological or synthetic scaffold. We have developed a novel two-step culture approach that makes possible the in vitro formation of cartilaginous-like tissue by mature adult bovine chondrocytes without the aid of a synthetic matrix. The first step consists of culturing chondrocytes under conditions that maintain their rounded shape and their molecular phenotype as assessed by type II collagen and aggrecan production. This step was accomplished by culturing the isolated chondrocytes in alginate beads until the cells have reestablished a proteoglycan-rich cell-associated matrix (CM). The second step consists of culturing the cells with their CM, after recovery from the beads, on a tissue culture insert with a porous membrane. In this study, young adult bovine articular chondrocytes were cultured in alginate beads in the presence of 10% or 20% fetal bovine serum (FBS). After 7 days of culture, the alginate beads were dissolved by incubating the beads for 20 min in sodium citrate buffer, a calcium chelator. Following a brief centrifugation, the cells with their CM were recovered, resuspended in medium containing 10% or 20% FBS and seeded onto a tissue culture insert. After 1 week of culture on the insert, the individual cells with their CM progressively became incorporated into a mass of cartilaginous tissue. Culture with 20% FBS resulted in the best formation of tissues. These tissues, easily recovered from the insert, were then subjected to biochemical and histological analyses. The biochemical results showed that the chondrocytes remain phenotypically stable in the tissues. The de novo tissue has a relatively high ratio of PG/collagen. Histological examination of the tissue revealed it contained a cartilage-like matrix strongly stained with toluidine blue. This scaffold-free system appears ideal to study, in vitro, the development of transplantable cartilaginous tissue.     

Study on therapeutic mechanism of Neiyifang in treating endometriosis

Objective: To observe the clinical effect of Neiyifang (NYF) in treating endometriosis and to explore its therapeutic mechanism through observing its influence on plasma β-endorphin (β-EP) in different menstrual stages and levels of prostaglandins (PGs) in menstruation.Methods:NYF was administered to 104 patients with endometriosis one dose daily with 3 successive menstrual cycles as one therapeutic course. Peripheral blood β-EP level in follicular, luteal and menstrual stages, as well as PGF_2α, PGE2, thromboxane B₂ and 6-keto-PGFl α levels in menstrual stage were detected by RIA, and controlled with those in 15 healthy persons.Results: (1) The total effective rate of NYF was 81.3% and it showed significant effect in improving patients’ clinical symptoms and physical signs; (2) In menstrual stage, the levels of β-EP, 6-keto-PGF_α/ TXB₂ were lower(P <0.05) and levels of PGF_2α, PGE₂, TXB₂ and 6-keto-PGF_1α were higher (P< 0. 05) in patients than those in control, and the higher the level of PGE₂, the severer the menalgia, (3) NYF could increase levels of β-EP, 6-keto-PGF_1α, and reduce levels of PGF_2α, PGE_2α in menstrual stage of patients (all P<0.05).Conclusion: (1) NYF has good clinical effect in treating endometriosis; (2) Patients’ symptom of menalgia is closely related with the excessive high levels of PGF_2α and PGE₂, PGI₂/TXA₂ ratio disturbance, and excessive low level of β-EP; (3) NYF could significantly decrease the PGE₂, PGF_1α levels, increase the 6-keto-PGF_1α/TXB₂ ratio and the level of β-EP, so as to alleviate the menalgia in patients with endometriosis. This item was supported by National Funds of Natural Sciences(No. 30070942)     

Prior immunologic experience potentiates the subsequent antibody response when Salmonella strains are used as vaccine carriers.

Prior immunologic experience with homologous and heterologous serotype Salmonella strains potentiated the subsequent antibody response when the same strains were used as vaccine carriers of foreign antigens. This potentiation was positively correlated with the appearance of antibody directed against the lipopolysaccharide of the carrier strain. Both serum and mucosal antibody responses against the foreign antigen increased over time. Antibody responses in sera of animals primed with either the homologous or heterologous serotype strain were not statistically significantly different, while animals primed with the homologous serotype strain developed significantly better mucosal antibody responses against the foreign antigen.     

Effect of maternal administration of thyrotropin-releasing hormone or DN1417 on functional and morphologic fetal rabbit lung maturation and duration of survival after premature delivery

Though maternal treatment with thyrotropin-releasing hormone (TRH) for prevention of hyaline membrane disease has been utilized, precise mechanisms of TRH in accelerating fetal lung maturation remain unclear. We studied the effect of maternally administered TRH or DN1417 (an analog of TRH) on functional and morphologic fetal rabbit lung maturation and the duration of survival after premature delivery. Because DN1417 retains the neurotransmitter but not the neuroendocrine effects of TRH, this study enables us to determine which of these effects was responsible for enhancement of lung maturation. TRH or DN1417 (0.2 mg/kg/dose) or saline was injected intravenously into New Zealand White rabbit does 48, 36, 24, 12 and 2 h prior to sacrifice on day 27 of gestation. Functional pulmonary maturity was assessed by pressure-volume hysteresis, and morphologic maturity was assessed by histologic technique. Maternal administration of TRH or DN1417 enhanced both functional and morphologic fetal lung maturation as well as the duration of neonatal survival after premature delivery. We propose that the effect of TRH in fetal lung maturation is due to neurotransmitter rather than neuroendocrine effects.     

Psychophysiological activity and neuropsychological test performance in alcoholics.

This study examined electromyogram (EMG) and skin conductance level (SCL) as mediators of neuropsychological test performance of alcoholics. Alcoholics and controls with high EMG performed less well than low EMG subjects on 12 measures of neuropsychological performance. For SCL, the alcoholics and controls in the Low Group did not differ from those in the High Group on any measure. Analyses that used information intake (Low EMG and High SCL) and rejection (High EMG and Low SCL) information postures (IPs) demonstrated that the intake group outperformed the rejection group on 10 neuropsychological measures. Subjects with intake IPs reported more stimulation, concentration, and interest during the tasks than did subjects with rejection IPs. Results suggest that IPs can be used to identify alcoholics with neuropsychological deficits.