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991.
Khatik GL Kaur J Kumar V Tikoo K Venugopalan P Nair VA 《European journal of medicinal chemistry》2011,46(8):3291-3301
The paper discusses the synthesis and stereochemical aspects of the anti aldol products, 3-(substituted phenyl)-5-[(substituted phenyl) hydroxy methyl]-5-methyl-4-oxo-2-thioxoimidazolidines. The stereochemistry observed in the aldol reactions with benzaldehydes was explained by transition state model of the endocyclic (E)-enolate formed from the rigid 4-oxo-2-thioxoimidazolidine skeleton. Proton NMR and ROESY spectral analyses were carried out to identify the syn and anti conformations of the aldol diastereomers. Configurations of the enantiomers of the representative anti aldol product 3-(4-chlorophenyl)-5-[(4-chlorophenyl) hydroxy methyl]-5-methyl-4-oxo-2-thioxoimidazolidine was determined by single crystal XRD studies. The compounds were screened in vitro against prostate cancer cell lines, PC-3 and LNCaP and the most potent derivatives were identified. 相似文献
992.
A major challenge for poultry vaccination is the design of vaccines that protect against multiple pathogens via a single protective dose delivered through mass vaccination methods. In this investigation, we examined herpesvirus of turkeys (HVT) as a vaccine vector for delivery of haemagglutinin (HA) antigen of highly pathogenic H7N1 avian influenza virus that can act as a dual vaccine against avian influenza and Marek's disease. The HVT vector was developed using reverse genetics based on an infectious bacterial artificial chromosome (BAC) clone of HVT. The BAC carrying the HVT genome was genetically modified to express the HA gene of a highly pathogenic H7N1 virus. The resultant recombinant BAC construct containing the modified HVT sequence was transfected into chicken embryo fibroblast (CEF) cells, and HVT recombinants (rHVT-H7HA) harbouring the H7N1 HA were recovered. Analysis of cultured CEF cells infected with the rHVT-H7HA showed that HA was expressed and that the rescued rHVT-H7HA stocks were stable during several in vitro passages with no difference in growth kinetics compared with the parent HVT. Immunisation of one-day-old chicks with rHVT-H7HA induced H7-specific antibodies and protected chickens challenged with homologous H7N1 virus against virus shedding, clinical disease and death. This vaccine supports differentiation between infected and vaccinated animals (DIVA) vaccination strategies because no nucleoprotein-(NP) specific antibodies were detected in the rHVT-H7HA vaccinated birds. The rHVT-H7HA not only provided protection against a lethal challenge with highly pathogenic H7N1 virus but also against highly virulent Marek's disease virus and can be used as a DIVA vaccine. 相似文献
993.
Nair H Brooks WA Katz M Roca A Berkley JA Madhi SA Simmerman JM Gordon A Sato M Howie S Krishnan A Ope M Lindblade KA Carosone-Link P Lucero M Ochieng W Kamimoto L Dueger E Bhat N Vong S Theodoratou E Chittaganpitch M Chimah O Balmaseda A Buchy P Harris E Evans V Katayose M Gaur B O'Callaghan-Gordo C Goswami D Arvelo W Venter M Briese T Tokarz R Widdowson MA Mounts AW Breiman RF Feikin DR Klugman KP Olsen SJ Gessner BD Wright PF Rudan I Broor S Simões EA Campbell H 《Lancet》2011,378(9807):1917-1930
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Kasar PA Ravikumar R Varghese R Kotecha M Vimala J Kumar RN 《Asian cardiovascular & thoracic annals》2011,19(5):324-332
Echocardiography is often inadequate for imaging tetralogy of Fallot, prompting cineangiography. This study prospectively evaluated multidetector computed tomographic angiography for preoperative evaluation of tetralogy of Fallot in 112 consecutive patients. Forty-eight had nonconfluent or hypoplastic pulmonary arteries (mean z-score, -2; range, -11.1-0.13) permitting only palliative or no surgery; 64 had adequate pulmonary artery anatomy (mean z-score, 0.59; range, -2.53-3.4) allowing total repair. The surgical data of 50 patients who underwent total correction were compared with transthoracic echocardiography and multidetector computed tomographic angiography findings. Multidetector computed tomographic angiography tended to reveal unsuspected collaterals and coronary abnormalities besides outlining the right ventricular outflow tract and pulmonary artery branches. The branch pulmonary artery diameter z-score was the most important determinant of surgical strategy, with the worst figures being associated with no surgical options or palliative surgery, and the best figures leading to corrective surgery. The mean radiation dose was 3.45 mSv. Multidetector computed tomographic angiography is a powerful supplement to echocardiography in the preoperative evaluation of tetralogy of Fallot. 相似文献
997.
Asthma in the elderly is often underrecognized and suboptimally treated, resulting in an increased morbidity and mortality. The characteristics of asthma-related bronchitis and its optimal treatment remain to be determined in this population. We aimed to compare lung function and airway inflammation in elderly and younger asthmatic subjects. Data from two induced sputum databases were analyzed in three groups of asthmatic subjects (18-30 y, n = 136; 31-59 y, n = 385; 60-72 y, n = 172) and one group of healthy elderly subjects (60-89 y, n = 16). Expiratory flows and induced sputum cell counts were analyzed. Airway obstruction was more marked in elderly asthmatics compared with healthy elderly or younger asthmatic subjects (p < 0.01). An increase in sputum neutrophils and a decrease in macrophages and lymphocytes were observed in elderly asthmatics (p < 0.0001). Neutrophil percentages significantly increased with asthma severity in the young and the middle-aged groups, while they remained similar in elderly asthmatics regardless of asthma severity (p < 0.05). Neutrophil percentages weakly correlated with the dose of ICS in all asthmatics (r = 0.17, p < 0.0001). Age and dose of ICS were independent predictors of neutrophil percentage in asthmatic subjects in a regression model (R(2) = 0.12). Asthma in the elderly is associated with a more marked airway obstruction and sputum neutrophilia. Both age and the dose of corticosteroids need to be considered in the interpretation of the clinical relevance of sputum neutrophil count. 相似文献
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Nair SS 《Indian journal of medical ethics》2011,8(2):102-106
This paper identifies some ethical concerns regarding the Revised National Tuberculosis Control Programme (RNTCP). Only 10% of those with chest symptoms visiting public health facilities get specific treatment as they are diagnosed with TB. The remaining 90% who suffer from non-TB diseases are not given scientific treatment. This compartmental approach denies treatment to millions of people with chest symptoms. It has also eroded the popularity of public health facilities. Second, though 87% of those diagnosed on the basis of x-ray alone are unlikely to have TB, such unethical wrong diagnoses continue to be carried out under the TB programme. Still worse, the RNTCP's expectation that only half of TB cases should be smear positive effectively permits up to 50% of diagnoses to be wrong. The actual extent of wrong diagnosis is even higher as the majority of people with chest symptoms first visit private health facilities which base their diagnosis almost exclusively on radiological examination. Third, though 25% to 33% of TB cases get cured spontaneously, and at least two-thirds were cured even with incomplete treatment, the RNTCP insists on full treatment for all TB cases. This over-treatment is unethical, wasteful and also tantamount to scientific dishonesty. Studies to identify different categories of cases (those needing full treatment, short treatment or no treatment) have not been attempted. The introduction (under the RNTCP) of the "success rate"in preference to the well recognised "cure rate" was unethical and unwarranted. "Crying wolf" over Multiple Drug Resistant (MDR) TB to justify DOTS when there is no apparent alarming increase in the incidence of initial MDR tuberculosis cases is also questionable. Other ethical concerns about the RNTCP include the irrational choice of districts leading to exclusion of those that need the services most; exclusion of diagnosed patients from the DOTS scheme, and exclusion from treatment on non-medical grounds. Such exclusions can be up to 58% of TB cases. 相似文献