维甲酸和联合应用神经营养因子对新生大鼠神经干细胞分化的影响

目的研究全反式维甲酸（ATRA）及联合应用神经营养因子（BDNF，GDNF）对体外培养的神经干细胞（NSCs）分化的影响。方法取新生SD大鼠的前脑室下带（SVZ）区，按NSCs的常规培养方法分离、培养。用免疫细胞化学法鉴定巢蛋白（nestin）、微管相关蛋白-2（MAP-2）、胶质原纤维酸性蛋白（GFAP）的表达，以此来观察ATRA、BDNF、GDNF单独或联合应用对次代神经球细胞分化的作用。结果原代及次代神经球均显示nestin阳性，并可分化为MAP-2阳性神经元样细胞及GFAP阳性胶质细胞样细胞。1μmol／LATRA可促进NSCs分化为MAP-2阳性细胞的比例达（29．14±5．00）％，显著高于对照组的（7．19±1．21）％，差异有高度统计学意义（P〈0．001）。ATRA联合应用10ng／ml的BDNF或GDNF，与单独使用ATRA比较，并不显著提高NSCs分化为MAP-2阳性细胞的比例。结论ATRA可促进神经干细胞向神经元方向分化，ATRA联合应用BDNF或GDNF无明显的协同作用。     

MDR1 基因单靶点双荧光素酶报告基因系统的建立

目的通过构建以MDR1启动子为启动序列的双荧光素酶报告基因系统并进行活性分析，为MDR1基因表达的单靶点调控研究和逆转剂的筛选提供一种有效的方法。方法从HCT-8细胞中提取DNA并克隆含有MDR1基因启动子中Y—box序列。将该序列重组到萤光素酶报告基因载体pGL-3．Basic的启动区域中，从而构建报告基因载体pGL-MDR1。将pGL-MDR1和pRL-TK载体共转染到HCT-8和HCT-8／VCR细胞中。通过调节不同载体的比例来优化转染效率。利用MDRI基因激活剂（热诱导）和抑制剂（EGCG）等处理来分析其启动转录活性受外界因素的影响。结果通过直接测序法验证了pGL-MDR1含有MDR1基因启动子Y—box序列且没有出现碱基突变。在pGL-MDR1和pRL-TK的转染比例为5：5时，转染效率最高并具有最高的萤光素酶活性。通过MDR1基因激活处理后表现为时间依赖性地激活MDR1基因的表达，而MDR1基因抑制剂的作用则相反。结论MDR1启动子为启动序列的双荧光素酶报告基因系统建立成功。该系统不但可以用于研究活体生物发光成像和MDRI基因表达的机理，而且可用于单靶点的多药耐药抑制剂的筛选。     

Relations between age, metabolic control, disease adjustment and psychological aspects in insulin-dependent diabetes mellitus

The relations between age, metabolic control, disease adjustment, and psychological factors in boys and girls with recently diagnosed insulin-dependent diabetes mellitus (IDDM) were studied. Older girls had significant higher postremission glycosylated haemoglobin A (Hb A_lc) levels ( p = 0.008). Girls with more hospitalizations had a lower developmental level ( p = 0.05), and had significantly more problems in the behavioural rating ( p = 0.05). Boys with more hospitalizations had a more external locus of control ( p = 0.01), more difficulties with disease adjustment, more emotional problems, and were also clinically assessed as having more behavioural problems. Boys showing more difficulties in psychological adjustment to the disease also had higher postremission Hb A_1clevels ( p = 0.02). Although Swedish children with IDDM of short disease duration do not differ from healthy children in important psychological aspects, older girls and a small group of problematic younger boys are at risk of developing metabolic imbalance after a short disease duration.     

Metabolic effects of growth hormone treatment: an early predictor of growth response?

Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months.     

HIV-1tat induced apoptosis of T-cells is not mediated by TGF-β

Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant role in mediatingtat induced T-cell apoptosis.     

Pelvic malignant hemangiopericytoma mimicking an ovarian neoplasm; a case report

BACKGROUND: Malignant hemangiopericytoma (MHPC) is a rare vascular tumor and has been reported to occur in the musculature of the extremities, retroperitoneum and pelvis. Omental hemangiopericytomas (HPCs) are extremely rare. Synovial sarcomas and solitary fibrous tumors share histologic features with HPCs, causing diagnostic difficulties. Immunohistochemistry is essential for the diagnosis. CASE: A 74-year-old woman presented with an abdominopelvic mass. A malignant ovarian tumor was suspected on clinical features, ultrasound and computed tomography. Staging laparotomy revealed a large, vascular tumor adherent to loops of small bowel, colon, cecum and appendix, but the ovaries and uterus were normal. The tumor was completely removed after extensive dissection. Histopathology and detailed immunohistochemistry established the diagnosis of a malignant hemangiopericytoma arising from the omentum. The patient developed recurrent subacute bowel obstruction and died 4 months after the initial diagnosis. CONCLUSION: MHPCs are rare tumors and not likely to be diagnosed preoperatively. Treatment is therefore individualized and based on the findings at laparotomy. Some tumors, such as the one described here, exhibit very aggressive behavior.