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101.
OBJECTIVE: To estimate the magnitude of and socio-demographic factors related to substance use among street children in Delhi. DESIGN: Observational study. METHODS: 115 male street children aged 6 to 16 years were interviewed at the time of their admission to an observation home. RESULTS: More than half of the subjects had indulged in substance use before coming to the observation home. The agents consumed were nicotine,inhalants, alcohol and cannabis. On application of multiple logistic regression, maltreatment of the child by family members was found significant predictor of substance use in the study group. CONCLUSION: Substance use in street children is associated with unstable homes and maltreatment. 相似文献
102.
Activation of caspase-9 with irradiation inhibits invasion and angiogenesis in SNB19 human glioma cells 总被引:4,自引:0,他引:4
Yanamandra N Kondraganti S Srinivasula SM Gujrati M Olivero WC Dinh DH Rao JS 《Oncogene》2004,23(13):2339-2346
Glioblastoma multiforme, the most common brain tumor, typically exhibits markedly increased angiogenesis, which is crucial for tumor growth and invasion. Antiangiogenic strategies based on disruption of the tumor microvasculature have proven effective for the treatment of experimental brain tumors. Here, we have overexpressed human caspase-9 by stable transfection in the SNB19 glioblastoma cell line, which normally expresses low levels of caspase-9. Our studies revealed that overexpression of caspase-9 coupled with radiation has a synergistic effect on the inhibition of glioma invasion as demonstrated by Matrigel assay (> 65%). Furthermore, sense caspase stable clones cocultured with fetal rat brain aggregates along with radiation showed complete inhibition as compared to the parental and vector controls. During in vitro angiogenesis, SNB19 cells cocultured with human microvascular endothelial cells (HMEC) showed vascular network formation after 48-72 h. In contrast, these capillary-like structures were inhibited when HMEC cells were cocultured with sense caspase stable SNB19 cells. This effect was further enhanced by radiation (5 Gy). Signaling mechanisms revealed that apoptosis is induced by cleavage of caspase-9 by radiation, loss of mitochondrial membrane potential and activation of caspase-3. These results demonstrate that activation of caspase-9 disrupts glioma cell invasion and angiogenesis in vitro. Hence, overexpression of proapoptotic molecules such as caspase-9 may be an important determinant of the therapeutic effect of radiation in cancer therapy. 相似文献
103.
Inhibition of cathepsin B and MMP-9 gene expression in glioblastoma cell line via RNA interference reduces tumor cell invasion, tumor growth and angiogenesis 总被引:27,自引:0,他引:27
Extracellular proteases have been shown to cooperatively influence matrix degradation and tumor cell invasion through proteolytic cascades, with individual proteases having distinct roles in tumor growth, invasion, migration and angiogenesis. Matrix metalloproteases (MMP)-9 and cathepsin B have been shown to participate in the processes of tumor growth, vascularization and invasion of gliomas. In the present study, we used a cytomegalovirus promoter-driven DNA template approach to induce hairpin RNA (hpRNA)-triggered RNA interference (RNAi) to block MMP-9 and cathepsin B gene expression with a single construct. Transfection of a plasmid vector-expressing double-stranded RNA (dsRNA) for MMP-9 and cathepsin B significantly inhibited MMP-9 and cathepsin B expression and reduced the invasive behavior of SNB19, glioblastoma cell line in Matrigel and spheroid invasion models. Downregulation of MMP-9 and cathepsin B using RNAi in SNB19 cells reduced cell-cell interaction of human microvascular endothelial cells, resulting in the disruption of capillary network formation in both in vitro and in vivo models. Direct intratumoral injections of plasmid DNA expressing hpRNA for MMP-9 and cathepsin B significantly inhibited established glioma tumor growth and invasion in intracranial tumors in vivo. Further intraperitoneal (i.p.) injections of plasmid DNA expressing hpRNA for MMP-9 and cathepsin B completely regressed pre-established tumors for a long time (4 months) without any indication of these tumor cells. For the first time, these observations demonstrate that the simultaneous RNAi-mediated targeting of MMP-9 and cathepsin B has potential application for the treatment of human gliomas. 相似文献
104.
Prospective study of social and other risk factors for incidence of type 2 diabetes in the Whitehall II study 总被引:1,自引:0,他引:1
BACKGROUND: Social inequalities in the incidence of type 2 diabetes and the relation of health behaviors and psychosocial factors to the incidence of type 2 diabetes are not well established. METHODS: Prospective occupational cohort study of 10 308 civil servants aged 35 to 55 years at baseline in phase 1 (1985-1988). Diagnosis of diabetes was ascertained by questionnaire at baseline and follow-up at phases 2 (1989), 3 (1992-1993), 4 (1995), and 5 (1997-1999) and glucose tolerance tests in phases 3 and 5. RESULTS: Participants working in the lower employment grades had a higher incidence of diabetes than those in higher employment grades (men: odds ratio [OR], 2.9; 95% confidence interval [CI], 1.9-4.4; women: OR, 1.7 [95% CI, 0.8-3.7]). Body mass index and other risk factors considered traditional for type 2 diabetes were found to be so in this cohort. In men, of the psychosocial risk factors examined, only effort-reward imbalance was related to incidence of diabetes (OR, 1.7 [95% CI, 1.0-2.8]). The General Health Questionnaire depression subscale was related to incidence of diabetes and impaired glucose tolerance (OR, 1.25 [95% CI, 1.0-1.6]). These associations remained after adjustment for other confounding factors. In men only, social difference in incidence of diabetes was reduced but still significant after adjustment for conventional risk factors. CONCLUSIONS: An inverse relationship exists between social position and incidence of diabetes that is partly explained by health behaviors and other risk factors. Effort-reward imbalance, which is reportedly associated with coronary heart disease, is also associated with type 2 diabetes. 相似文献
105.
106.
Recent studies indicate that approaching death, rather than age, may be the main demographic driver of health care costs. Using a 29-year longitudinal English dataset, this paper uses more robust methods to examine the effects of age and proximity to death on hospital costs. A random effects panel data two-part model shows that approaching death affects costs up to 15 years prior to death. The large tenfold increase in costs from 5 years prior to death to the last year of life overshadows the 30% increase in costs from age 65 to 85. Hence, expenditure projections must consider remaining life expectancy in the populations. 相似文献
107.
The objective of our study was to prepare and evaluate osmotic matrix (OM) tablets of diclofenac sodium (DS). In vitro studies were done on USPXXIV dissolution apparatus II in different release medium. Surface characteristics of coating films and osmotic contribution of OM tablets also were studied. In vivo evaluation was carried out in 6 healthy human volunteers using HPLC method to assay plasma samples, and the results were compared with the performance of fabricated matrix and two commercial tablets of DS. Through in vitro drug release kinetics, using regression coefficient analysis and Peppas equation, different pharmacokinetic parameters and relative bioavailability were determined. OM tablets were found to provide more prolonged and controlled therapeutic plasma DS levels and also showed improved bioavailability in comparison to fabricated matrix and commercial tablets studied. 相似文献
108.
Meliodosis, an infectious disease caused by Burkholderia pseudomallei has been recognized as an emerging infectious disease in India. The infection is under diagnosed and underreported, and hence considered a rare disease. Majority of the cases have been documented from the states with heavy rainfall. The present case being reported is a middle-aged woman who had developed a fulminant infection following exposure to stagnant floodwater in the city of Hyderabad. To the best of our knowledge, this is the first case of Melioidosis being reported from this part of the country. 相似文献
109.
BACKGROUND: Uterine artery embolization by interventional radiologic techniques is an effective and widely used modality in the management of uterine leiomyomas. Anatomically, uterine arteries can be approached transvaginally with an appropriate surgical technique. In this report, we describe a novel, minimally invasive vaginal technique that also occluded the uterine arteries successfully. CASE: A 45-year-old woman with symptomatic leiomyomas decided to undergo a vaginal hysterectomy. During the procedure, Doppler ultrasonography demonstrated the cessation of blood flow after dissection and ligation of uterine arteries bilaterally without cutting the uterosacral and cardinal ligaments. CONCLUSION: Transvaginal ligation of the uterine arteries is possible. If validated by further clinical investigation, this minimally invasive gynecologic technique could be useful in selected cases of uterine leiomyomas. 相似文献
110.
Hillebrand L Harmanli OH Whiteman V Khandelwal M 《American journal of obstetrics and gynecology》2002,186(5):916-917
OBJECTIVE: Our purpose was to investigate the risk of urinary tract infections in pregnant women with bacterial vaginosis. STUDY DESIGN: In a cross-sectional study, 503 pregnant women were examined for bacterial vaginosis and urinary tract infections from July 1999 through April 2000. RESULTS: Nineteen (13.6%) of 140 women who had bacterial vaginosis had urinary tract infections compared with 24 (6.6%) of 363 women without it. Bacterial vaginosis in pregnancy was associated with an increased risk for urinary tract infections (odds ratio 2.21, 95% CI 1.16-4.18). CONCLUSION: Pregnant women with bacterial vaginosis are more likely to have urinary tract infections. 相似文献