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Ramanathan R Rasmussen MR Gerstmann DR Finer N Sekar K;North American Study Group 《American journal of perinatology》2004,21(3):109-119
We compared the onset of clinical response and safety of two surfactants, poractant alfa (Curosurf, Chiesi Pharmaceuticals, Parma, Italy) and beractant (Survanta, Ross Laboratories, Columbus, OH), for treatment of respiratory distress syndrome (RDS) in preterm infants weighing 750 to 1750 g at birth and <35 weeks gestation. The study was performed as a 20-center prospective, randomized, masked comparison trial. Preterm infants (n = 293) with RDS were randomized to receive an initial dose of either 100 (n = 96) or 200 (n = 99) mg/kg of poractant alfa or 100 ( n = 98) mg/kg of beractant. All repeat dosing was given at 100 mg/kg. The onset of clinical response after the first dose was studied by comparing changes in the fraction of inspired oxygen (F IO(2)) between 0 and 6 hours measured using the area under the curve (F IO(2) AUC (0-6)); other outcomes were assessed for the entire cohort at 28 days and for infants born at < or = 32 weeks gestation at 36 weeks postconceptional age. We found that the mean F IO(2) AUC (0-6) values for the 100 and 200 mg/kg poractant alfa groups were both significantly lower than the mean F IO(2) AUC (0-6) values for the beractant group ( p < 0.005) but were not different from each other. Other outcomes were not different among the three groups for the entire cohort, but in infants born at < or = 32 weeks gestation, mortality up to 36 weeks postconceptional age was significantly less in the 200 mg/kg poractant alfa group than in either the beractant group (3% versus 11%; p = 0.034) or in the 100 mg/kg poractant alfa group (3% versus 11%; p = 0.046). Need for more than one dose of surfactant was significantly lower in infants treated with an initial dose of 200 mg/kg poractant alfa in comparison to the beractant-treated group ( p < 0.002). Treatment with poractant alfa (200 mg/kg initial dose) resulted in rapid reduction in supplemental oxygen with fewer additional doses of surfactant versus treatment with beractant in infants <35 weeks gestation with RDS, and significantly reduced mortality ( p <0.05) than either beractant or poractant alfa (100 mg/kg dosing) in infants < or =32 weeks gestation with RDS. 相似文献
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Kumar SA Sudhahar V Varalakshmi P 《Clinica chimica acta; international journal of clinical chemistry》2005,355(1-2):197-204
BACKGROUND: Dietary cholesterol plays an important role in development of atherogenesis and cardiovascular disease. We explored the lipemic-oxidative injury in the hypercholesterolemic atherogenic animals. The effects of eicosapentaenoic acid (EPA), dl-alpha-lipoic acid (LA) and eicosapentaenoate-lipoate derivative (EPA-LA) were tested for their efficacy in controlling the atherogenic disturbances. METHODS: Four groups of male Wistar rats were fed with a high cholesterol diet (rat chow supplemented with 4% cholesterol and 1% cholic acid; HCD) for 30 days. Of these groups, 3 groups of rats were treated with either EPA (oral gavage, 35 mg/kg body weight/day), LA (oral gavage, 20 mg/kg body weight/day) or EPA-LA derivative (oral gavage, 50 mg/kg body weight/day) from 16th day to 30th day of the experimental period. RESULTS: HCD induced abnormal increase in lipid peroxidation and serum cholesterol, triglyceride, LDL and VLDL, and a decreased HDL concentration. Altered activity of cardiac and serum creatine kinase, accompanied by a depressed cardiac enzymatic and nonenzymatic antioxidants defense system were observed in HCD fed rats. These changes were partially restored in the EPA and LA treated groups, however, their combined derivative EPA-LA more effectively restored the altered parameters near to that of control (P<0.05). CONCLUSION: Lipid abnormalities and oxidative injury were induced by a hypercholesterolemic diet. Administration of the combination treatment of EPA-LA afforded protection against the lipemic-oxidative injury. 相似文献
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Decreased bioavailability of rifampin and other antituberculosis drugs in patients with advanced human immunodeficiency virus disease 下载免费PDF全文
Gurumurthy P Ramachandran G Hemanth Kumar AK Rajasekaran S Padmapriyadarsini C Swaminathan S Bhagavathy S Venkatesan P Sekar L Mahilmaran A Ravichandran N Paramesh P 《Antimicrobial agents and chemotherapy》2004,48(11):4473-4475
We evaluated the effects of human immunodeficiency virus (HIV) disease on pharmacokinetics of antituberculosis medications by measuring concentrations of isoniazid and rifampin in blood and of pyrazinamide and ethambutol in urine. Peak concentration and exposure were reduced for rifampin, and rapid acetylators of isoniazid had lower drug levels. HIV and HIV-tuberculosis patients who have diarrhea and cryptosporidial infection exhibit decreased bioavailability of antituberculosis drugs. 相似文献
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Mitchell GF Guo CY Kathiresan S Vasan RS Larson MG Vita JA Keyes MJ Vyas M Newton-Cheh C Musone SL Camargo AL Drake JA Levy D O'Donnell CJ Hirschhorn JN Benjamin EJ 《Hypertension》2007,49(6):1285-1290
Arterial stiffness is a moderately heritable trait that is affected by alterations in the bioavailability of NO. Previous studies have found associations between variants in the gene for endothelial NO synthase (NOS3) and arterial properties. We previously identified a linkage peak for forward pressure wave amplitude in the immediate vicinity of NOS3. Therefore, we evaluated relations between arterial stiffness measures and common genetic variants at this locus. Eighteen single nucleotide polymorphisms capturing approximately 90% of underlying common variation in NOS3 were genotyped in unrelated Framingham Heart Study participants (N=1157; 52.2% women; mean age: 62 years) with routinely ascertained tonometry data that provided 5 arterial phenotypes (forward and reflected pressure wave amplitude, central pulse pressure, carotid-femoral pulse wave velocity, and mean arterial pressure). In women but not men, the genotype for the common NOS3 missense mutation (Glu298Asp, rs1799983) was related to central pulse pressure (women: GG=53+/-0.9, GT=54+/-0.9, and TT=47+/-2.0 mm Hg, P=0.0047; men: GG=50+/-1.0, GT=49+/-0.9, and TT=47+/-1.8 mm Hg, P=0.30) and forward wave amplitude (women: GG=41+/-0.7, GT=42+/-0.7, and TT=38+/-1.6 mm Hg, P=0.029; men: GG=42+/-0.9, GT=41+/-0.8, and TT=39+/-1.5 mm Hg, P=0.47). The only other nominally significant sex-specific association in men but not women was between an intronic polymorphism (rs1800781) and reflected wave amplitude (women: AA=10.4+/-0.4, AG=11.1+/-0.6, and GG=8.9+/-2.2 mm Hg, P=0.50; men: AA=6.1+/-0.3, AG=7.3+/-0.5, and GG=11.3+/-2.3 mm Hg, P=0.014). After adjusting for multiple testing (18 polymorphisms and 5 phenotypes), these nominal associations were no longer significant. The present study was suggestive of modest relations between common genetic variants at the NOS3 locus and arterial stiffness. 相似文献
40.
Nagarajan Vishali Krishnaswamy Kamakshi Sekar Suresh Seppan Prakash 《Phytotherapy research : PTR》2011,25(1):53-58
Depletion of estrogens occurs in women during menopause, while in experimental animals, oophorectomy is a common method to deplete the animals of their gonadal hormones. Recently, phytoestrogens derived from plants have been tried as estrogen substitutes during menopause. In the present study an isoflavones methanol extract from red clover Trifolium pratense (Linn.) was administered orally (500 mg/kg of body weight) to ovariectomized (OVX) and normal (controls) rats for 90 and 180 days. Their pain threshold was monitored using tail flicking and formalin test methods. Observations showed that the OVX rat pain threshold was reduced due to estrogen deprivation, whereas the pain threshold levels in OVX rats treated with isoflavones extract was similar to the control animals. The present study demonstrated the influence of phytoestrogen on long‐term OVX rats in pain perception in the absence of ovarian estrogen and without toxic side effects. However, the actions of gonadal hormones on nociceptive axis are myriad and complex, so further studies on the exact physiological mechanism of the phytoestrogen action on nociceptive axis is warranted. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献