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排序方式: 共有592条查询结果,搜索用时 15 毫秒
1.
Michael D Seidman Mumtaz J Khan Wen Xue Tang Wayne S Quirk 《Otolaryngology--head and neck surgery》2002,127(3):138-144
OBJECTIVES: Lecithin is a polyunsaturated phosphatidylcholine (PPC), which are high energy functional and structural elements of all biologic membranes. PPC play a rate-limiting role in the activation of numerous membrane-located enzymes, including superoxide dismutase and glutathione, which are important antioxidants protecting cell membranes from damage by reactive oxygen species (ROS). ROS-induced damage to mitochondrial DNA may lead to reduced mitochondrial function in the cochlea and resultant hearing loss. STUDY DESIGN AND SETTING: The effects of lecithin on aging and age-associated hearing loss were studied in rats by measuring hearing sensitivities using auditory brainstem responses (ABR). In addition, mitochondrial function as a measure of aging was assessed by determining mitochondrial membrane potentials using flow cytometry and by amplifying mitochondrial DNA deletions associated with aging. Harlan-Fischer rats aged 18 to 20 months (n = 14) were divided into 2 groups. The experimental group was supplemented orally for 6 months with lecithin, a purified extract of soybean phospholipid (Nutritional Therapeutics, Allendale, NJ). RESULTS: The data obtained were compared with the control group. ABRs were recorded at 2-month intervals and showed significant preservation of hearing sensitivities in the treated subjects. Flow cytometry revealed significantly higher mitochondrial membrane potentials in the treated subjects, suggesting preserved mitochondrial function. Finally, the common aging mitochondrial DNA deletion (mtDNA(4834)) were amplified from brain and cochlear tissue including stria vascularis and auditory nerve. This specific deletion was found significantly less frequent in all tissues in the treated group compared with the controls. CONCLUSION: These experiments support our hypothesis and provide evidence that lecithin may preserve cochlear mitochondrial function and protect hearing loss associated with aging. 相似文献
2.
Comorbidities in head and neck cancer: agreement between self-report and chart review. 总被引:1,自引:1,他引:0
Shraddha S Mukerji Sonia A Duffy Karen E Fowler Mumtaz Khan David L Ronis Jeffrey E Terrell 《Otolaryngology--head and neck surgery》2007,136(4):536-542
OBJECTIVES: To determine the accuracy of self-reported comorbidities compared with medical record review and the clinical and sociodemographic characteristics associated with accuracy of self-reported comorbidities. STUDY DESIGN: We conducted a prospective study of 458 newly diagnosed head and neck cancer patients using self-administered questionnaire and medical chart review data. Overall and itemwise consistency between self-report and chart review was evaluated. Social, clinical, and demographic characteristics of consistent versus inconsistent responders were analyzed. RESULTS: Seventy-four percent of patients had at least one comorbidity. There was good overall consistency between self-report and chart review (kappa = 0.50). Compared with consistent responders, inconsistent responders were found to be older (P < 0.05), have lower sleep (P < 0.05) and physical activity scores (P < 0.05), be more depressed (P < 0.05), and have more severe comorbidities (P < 0.05). CONCLUSIONS AND SIGNIFICANCE: Self-report may be considered as an alternative to chart review for comorbidity assessment in head and neck cancer patients. Younger patients, those with good general health, fewer depressive symptoms, and mild comorbidities, are more likely to give responses consistent with chart review. 相似文献
3.
Enzyme immunoassay compared with cell culture and immunofluorescence for detecting genital chlamydia. 总被引:5,自引:1,他引:5
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A novel enzyme immunoassay test (Pharmacia EIA) was evaluated against cell culture for the detection of chlamydial genital infection. Specimens were obtained from 525 patients (257 men and 268 women). Sensitivity, specificity, predictive value of positive (PVP) and predictive value of negative (PVN) for the new test were, respectively, 83.6, 98.5, 94.4 and 95.1% for men and 86, 97.2, 87.8 and 96.8% for women. Discrepancies were further evaluated by repeating the EIA, and by direct immunofluorescence on the EIA transport buffer. The sensitivity, specificity, PVP and PVN of the EIA against the combination of cell culture and direct immunofluorescence were, respectively 85.9, 100, 100, and 95.5% for men, and 90.5, 98.1, 92.3 and 97.7% for women. Overall agreement between the EIA and the combination of cell culture and direct immunofluorescence was 97%. The Pharmacia EIA is rapid and simple to perform and does not require elaborate equipment. 相似文献
4.
Wasim Jafri Khalid Mumtaz William P Burdick Page S Morahan Rosslynne Freeman Tabassum Zehra 《BMC medical education》2007,7(1):34
Background
Residents play an important role in teaching of medical undergraduate students. Despite their importance in teaching undergraduates they are not involved in any formal training in teaching and leadership skills. We aimed to compare the teaching skills of residents with faculty in facilitating small group Problem Based Learning (PBL) sessions. 相似文献5.
6.
Balkhi MY Latchumanan VK Singh B Sharma P Natarajan K 《Journal of leukocyte biology》2004,75(5):874-883
We report that stimulation of Mycobacterium tuberculosis secretory antigen- and tumor necrosis factor alpha-matured BALB/c mouse bone marrow dendritic cells (BMDCs) with anti-CD80 monoclonal antibody up-regulated CD86 levels on the cell surface. Coculture of these BMDCs with na?ve, allogeneic T cells now down-regulated T helper cell type 1 (Th1) responses and up-regulated suppressor responses. Similar results were obtained with splenic CD11c(+)/CD8a(-) DCs but not to the same extent with CD11c(+)/CD8a(+) DCs. Following coculture with T cells, only BMDCs and CD11c(+)/CD8a(-) DCs and not CD11c(+)/CD8a(+) DCs displayed increased levels of surface CD86, and further, coculturing these DCs with a fresh set of T cells attenuated Th1 responses and increased suppressor responses. Not only na?ve but even antigen-specific recall responses of the Th1-committed cells were modulated by DCs expressing up-regulated surface CD86. Further analyses showed that stimulation with anti-CD80 increased interleukin (IL)-10 and transforming growth factor-beta-1 levels with a concomitant reduction in IL-12p40 and interferon-gamma levels from BMDCs and CD11c(+)/CD8a(-) DCs and to a lesser extent, from CD11c(+)/CD8a(+) DCs. These results suggest that cross-talk between costimulatory molecules differentially regulates their relative surface densities leading to modulation of Th responses initiated from some DC subsets, and Th1-committed DCs such as CD11c(+)/CD8a(+) DCs may not allow for such modulation. Cognate antigen-presenting cell (APC):T cell interactions then impart a level of polarization on APCs mediated via cross-regulation of costimulatory molecules, which govern the nature of subsequent Th responses. 相似文献
7.
Sathanandam S Anand Subramanyam N Murthy Vishal S Vaidya Moiz M Mumtaz Harihara M Mehendale 《Food and chemical toxicology》2003,41(8):1123-1132
The objective of this study was to evaluate the interaction profile of chloroform (CHCl(3))+allyl alcohol (AA) binary mixture (BM)-induced acute hepatotoxic response. Plasma alanine aminotransferase (ALT) was measured to assess liver injury, and 3H-thymidine (3H-T) incorporation into hepatonuclear DNA was measured as an index of liver regeneration over a time course of 0-72 h. Male Sprague-Dawley (S-D) rats received single ip injection of 5-fold dose range of CHCl(3) (74, 185 and 370 mg/kg) in corn oil (maximum 0.5 ml/kg) and 7-fold dose range of AA (5, 20 and 35 mg/kg) in distilled water simultaneously. The doses for BM were selected from individual toxicity studies of CHCl(3) alone [Int. J. Toxicol. 22 (2003) 25], and AA alone [Reg. Pharmacol. Toxicol. 19 (1999) 165]. Since the highest dose of each treatment (CHCl(3)- 740 and AA- 50 mg/kg) yielded mortality due to the suppressed tissue repair followed by liver failure, this dose was omitted for BM. The levels of CHCl(3) (30-360 min) and AA (5-60 min) were quantified in blood and liver by gas chromatography (GC). The liver injury was more than additive after BM compared to CHCl(3) alone or AA alone at highest dose combination (370+35 mg/kg), which peaked at 24 h. The augmented liver injury observed with BM was consistent with the quantitation data. Though the liver injury was higher, the greater stimulation of tissue repair kept injury from progressing, and rescued the rats from hepatic failure and death. At lower dose combinations, the liver injury was no more than additive. Results of the present study suggest that liver tissue repair, in which liver tissue lost to injury is promptly replaced, plays a pivotal role in the final outcome of liver injury after exposure to BM of CHCl(3) and AA. 相似文献
8.
Possible role of endothelin-1 in the rabbit urinary bladder hyperplasia secondary to partial bladder outlet obstruction 总被引:1,自引:0,他引:1
Khan MA Shukla N Auld J Thompson CS Mumtaz FH Stansby GP Morgan RJ Mikhailidis DP 《Scandinavian journal of urology and nephrology》2000,34(1):15-20
OBJECTIVES: Urinary bladder hypertrophy and hyperplasia are common features of bladder outlet obstruction (BOO). The urinary bladder is known to synthesize endothelin-1 (ET-1), which is a potent vasoconstrictor peptide with mitogenic properties. Using an animal model of partial BOO, we investigated the potential role of ET-1 and its receptor subtypes (ET(A) and ET(B)) in bladder smooth muscle cell (SMC) proliferation. MATERIALS AND METHODS: Partial BOO was produced in adult male New Zealand White rabbits. After 3 weeks, the bladder was removed and SMCs from the dome and bladder neck were grown using standard explant methodology. At passage 2, the cells were made quiescent and then further incubated in foetal calf serum (FCS), control age-matched rabbit serum (CRS) or partial BOO serum (BRS) in the presence or absence of ET(A)-antagonist (BQ123) or ET(B)-antagonist (BQ788). SMC proliferation was then measured 24 h later with 5-bromo-2'deoxy-uracil and by cell counting using a haemocytometer at 48 h. Immunostaining for alpha-actin was performed on detrusor and bladder neck cells to confirm the presence of smooth muscle cells. RESULTS: BQ123 and BQ788 did not influence detrusor or bladder neck SMC proliferation in FCS or CRS. However, in the presence of BRS, BQ123 and BQ788 (100 nmol/L) significantly (p = 0.008) inhibited detrusor and bladder neck SMC proliferation. Cell counts were significantly reduced from the detrusor (p = 0.03, p = 0.01 with BQ123 and BQ788, respectively) and bladder neck (p = 0.01 for both BQ123 and BQ78). CONCLUSIONS: These results suggest that ET antagonists may have a role in preventing SMC hyperplasia associated with partial BOO. 相似文献
9.
Lipiar K. M. O. Goni Mohammad A. Jafar Mazumder Divya B. Tripathy Mumtaz A. Quraishi 《Materials》2022,15(21)
The phenomenon of corrosion threatens metallic components, human safety, and the economy. Despite being eco-friendly and promising as a corrosion inhibitor, acridine has not been explored to its full potential. In this review, we have discussed multiple biological activities that acridines have been found to show in a bid to prove that they are environmentally benign and much less toxic than many inhibitors. Some synthetic routes to acridines and substituted acridines have also been discussed. Thereafter, a multitude of acridines and substituted acridines as corrosion inhibitors of different metals and alloys in various corrosive media have been highlighted. A short mechanistic insight into how acridine-based compounds function as corrosion inhibitors have also been included. We believe this review will generate an impression that there is still much to learn about previously reported acridines. In the wake of recent surges to find efficient and non-toxic corrosion inhibitors, acridines and their analogs could be an appropriate answer. 相似文献
10.
Grant D. Stewart Sarah J. Welsh Stephan Ursprung Ferdia A. Gallagher James O. Jones Jacqui Shields Christopher G. Smith Thomas J. Mitchell Anne Y. Warren Axel Bex Ekaterini Boleti Jade Carruthers Tim Eisen Kate Fife Abdel Hamid Alexander Laird Steve Leung Jahangeer Malik Iosif A. Mendichovszky Faiz Mumtaz Grenville Oades Andrew N. Priest Antony C. P. Riddick Balaji Venugopal Michelle Welsh Kathleen Riddle Lisa E. M. Hopcroft NAXIVA Trial Group Robert J. Jones 《British journal of cancer》2022,127(6):1051
Background Surgery for renal cell carcinoma (RCC) with venous tumour thrombus (VTT) extension into the renal vein (RV) and/or inferior vena cava (IVC) has high peri-surgical morbidity/mortality. NAXIVA assessed the response of VTT to axitinib, a potent tyrosine kinase inhibitor.Methods NAXIVA was a single-arm, multi-centre, Phase 2 study. In total, 20 patients with resectable clear cell RCC and VTT received upto 8 weeks of pre-surgical axitinib. The primary endpoint was percentage of evaluable patients with VTT improvement by Mayo level on MRI. Secondary endpoints were percentage change in surgical approach and VTT length, response rate (RECISTv1.1) and surgical morbidity.Results In all, 35% (7/20) patients with VTT had a reduction in Mayo level with axitinib: 37.5% (6/16) with IVC VTT and 25% (1/4) with RV-only VTT. No patients had an increase in Mayo level. In total, 75% (15/20) of patients had a reduction in VTT length. Overall, 41.2% (7/17) of patients who underwent surgery had less invasive surgery than originally planned. Non-responders exhibited lower baseline microvessel density (CD31), higher Ki67 and exhausted or regulatory T-cell phenotype.Conclusions NAXIVA provides the first Level II evidence that axitinib downstages VTT in a significant proportion of patients leading to reduction in the extent of surgery.Clinical trial registration .Subject terms: NCT03494816Surgical oncology, Renal cell carcinoma, Predictive markers 相似文献