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992.
Talwar S Choudhary SK Reddy S Saxena A Kothari SS Juneja R Airan B 《Interactive Cardiovascular and Thoracic Surgery》2008,7(6):1058-1061
We studied the anatomic characteristics and results of surgery in 27 patients with total anomalous pulmonary venous drainage who were 15 years or older between January 1997 and July 2007. Mean age was 19.7+/-11.6 years (15-48 years). The anatomic subtypes were supracardiac (n=15), cardiac (n=7), and mixed (n=5). Fourteen patients were in NYHA class II and 13 were in NYHA class III. Eleven patients had severe and the rest had moderate pulmonary arterial hypertension; six patients had significant right ventricular dysfunction. All patients underwent complete repair. A small inter-atrial communication was left open in four patients and in two patients, a fenestrated unidirectional valved patch was used to close the atrial septal defect. There were no early or late deaths. Follow-up was 3-127 months (mean 61.2+/-36.1 months). Twenty patients were in NYHA class I and seven were in class II. Echocardiography showed normal right and left ventricular function in all patients with reduction of pulmonary arterial pressures in 26 patients. One patient underwent radiofrequency ablation for new onset atrial flutter. Surgery can be safely undertaken in a few naturally selected group of patients with total anomalous pulmonary venous drainage who survive beyond childhood. 相似文献
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Ken Resnicow Sasiragha Priscilla Reddy Shamagonam James Riyadh Gabebodeen Omardien Nilen Sunder Kambaran Heinrich George Langner Roger D. Vaughan Donna Cross Greg Hamilton Tracy Nichols 《Annals of behavioral medicine》2008,36(3):231-243
Background Smoking rates are projected to increase substantially in developing countries such as South Africa.
Purpose The aim of this study was to test the efficacy of two contrasting approaches to school-based smoking prevention in South African
youth compared to the standard health education program. One experimental program was based on a skills training/peer resistance
model and the other on a harm minimization model.
Method Thirty-six public schools from two South African provinces, KwaZulu-Natal and the Western Cape, were stratified by socioeconomic
status and randomized to one of three groups. Group 1 (comparison) schools (n = 12) received usual tobacco use education. Group 2 schools (n = 12) received a harm minimization curriculum in grades 8 and 9. Group 3 schools (n = 12) received a life skills training curriculum in grades 8 and 9. The primary outcome was past month use of cigarettes
based on a self-reported questionnaire.
Result Five thousand two hundred sixty-six students completed the baseline survey. Of these, 4,684 (89%) completed at least one follow-up
assessment. The net change in 30-day smoking from baseline to 2-year follow-up in the control group was 6% compared to 3%
in both harm minimization (HM) and life skills training (LST) schools. These differences were not statistically significant.
Intervention response was significantly moderated by both gender and race. The HM intervention was more effective for males,
whereas the life skills intervention was more effective for females. For black African students, the strongest effect was
evident for the HM intervention, whereas the strongest intervention effect for “colored” students was evident for the LST
group.
Conclusion The two experimental curricula both produced similar overall reductions in smoking prevalence that were not significantly
different from each other or the control group. However, the impact differed by gender and race, suggesting a need to tailor
tobacco and drug use prevention programs. More intensive intervention, in the classroom and beyond, may be needed to further
impact smoking behavior.
相似文献
Ken ResnicowEmail: |
994.
Maxadilan is a vasodilator peptide isolated from sand fly salivary glands. The vasodilator effects of maxadilan are mediated by the PAC1 receptor, although maxadilan and PACAP do not share sequence homology. Sand flies are the vector of the parasitic disease leishmaniasis. The peptide aids the sand fly in obtaining a blood meal while enhancing the infectivity of leishmania parasites transmitted by this arthropod vector. Aspects of maxadilan, PAC1, and leishmaniasis are discussed. 相似文献
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The functional responses of endothelial cells are dependent on signaling from peptide growth factors and the cellular adhesion receptors, integrins. These include cell adhesion, migration, and proliferation, which, in turn, are essential for more complex processes such as formation of the endothelial tube network during angiogenesis. This study identifies the molecular requirements for the cross-activation between beta3 integrin and tyrosine kinase receptor 2 for vascular endothelial growth factor (VEGF) receptor (VEGFR-2) on endothelium. The relationship between VEGFR-2 and beta3 integrin appears to be synergistic, because VEGFR-2 activation induces beta3 integrin tyrosine phosphorylation, which, in turn, is crucial for VEGF-induced tyrosine phosphorylation of VEGFR-2. We demonstrate here that adhesion- and growth factor-induced beta3 integrin tyrosine phosphorylation are directly mediated by c-Src. VEGF-stimulated recruitment and activation of c-Src and subsequent beta3 integrin tyrosine phosphorylation are critical for interaction between VEGFR-2 and beta3 integrin. Moreover, c-Src mediates growth factor-induced beta3 integrin activation, ligand binding, beta3 integrin-dependent cell adhesion, directional migration of endothelial cells, and initiation of angiogenic programming in endothelial cells. Thus, the present study determines the molecular mechanisms and consequences of the synergism between 2 cell surface receptor systems, growth factor receptor and integrins, and opens new avenues for the development of pro- and antiangiogenic strategies. 相似文献
1000.
Signature abnormalities in the cell cycle and apoptotic pathway have been identified in mantle cell lymphoma (MCL), affording the opportunity to develop targeted therapies. In this study, we tested a novel class of kinase inhibitors, styryl sulfones, which differ from prior cell cycle inhibitors in that they are not related to purines or pyrimidines. We observed that two closely related compounds, ON013100 and ON01370, altered the growth and cell cycle status of MCL lines and potently inhibited the expression of several important molecules, including cyclin-dependent kinase 4, p53, mouse double minute 2 (MDM2), and cyclin D as well as increased cyclin B expression. Using both terminal deoxy transferase uridine triphosphate nick end-labelling and poly ADP-ribose polymerase assays, we found that these compounds caused apoptosis in MCL cells. In addition, using molecular analyses, we observed the modulation of caspase-3 activity but not the expression of B-cell lymphoma family molecules. Next, we investigated the cytotoxicity of the MCL lines upon treatment with styryl sulfone compounds in combination with other currently used chemotherapeutic agents, such as doxorubicin (DOX) or vincristine (VCR). We found that the combination of DOX plus styryl sulfone or VCR plus styryl sulfone increased cytotoxicity by one log scale, compared with the single styryl sulfone compound. Thus, styryl sulfones alone, or in combination with chemotherapeutic agents, present attractive opportunities for new drug development in MCL. 相似文献