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21.
R. Bhatnagar Y. R. Sharma R. B. Vajpayee M. Madan V. K. Chhabra N. Ram K. Mukesh R. V. Azad R. Sharma 《Digestive diseases and sciences》1989,34(11):1745-1750
We undertook a prospective study to test Simoons' hypothesis that in certain susceptible races milk exerts a cataractogenic effect. Overall milk intake in low lactase deficiency areas did not correlate with cataract occurrence. Subgrouping of cataract patients revealed that greater milk intake did show positive correlation with cortical cataracts. Cortical cataracts were also markedly more common in females. Analysis of data from three different regions showed greater milk intake in cortical cataract patients only. Our data indicate the importance of specifying cataract type in cataract studies and highlight the problem this approach brings forth. We noted no different trends in subjects from northwest and southeast India, although the number of subjects from the southeast was considerably less. Patients with early cortical cataracts may be advised to restrict milk intake.Part of this material was presented at second cataract epidemiology meeting at Bonn in March 1988. A brief report has been accepted for publication in the proceedings of the meeting to be published inDevelopment of Ophthalmology, Vol. 17, 1988. 相似文献
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Ahmed Mousa Altaf A. Kondkar Saleh A. Al-Obeidan Taif A. Azad Tahira Sultan Essam Osman Khaled K. Abu-Amero 《Saudi medical journal》2015,36(6):671-677
Objectives:
To compare the mean total antioxidant status (TAS) among 3 glaucoma types, namely: pseudoexfoliation glaucoma (PEG), primary open angle glaucoma (POAG), and primary angle closure glaucoma (PACG), and study its potential association with various clinical glaucoma-parameters.Methods:
In this case-control study, plasma samples were obtained between September 2013 and October 2014 from 340 glaucoma patients (PEG [n=54]; POAG [n=147]; PACG [n=139]), and 351 controls of matching age, gender, ethnicity, and 5 different systemic co-morbidities from King Abdulaziz University Hospital, Riyadh, Saudi Arabia. The TAS in all samples was determined by a colorimetric-based assay.Results:
The mean±standard deviation of TAS was significantly lower among cases: 0.77±0.32 than controls: 1.1±0.22, p<0.0001. Moreover, the TAS levels were significantly different across the 3 types of glaucoma: 0.86±0.24 in PEG, 0.47±0.32 in POAG, and 0.98±0.41 in PACG (all p<0.0001). In addition, there was a significant correlation between TAS and age at onset (Pearson correlation coefficient [R] 0.17, p<0.0001), cup/disc ratio (R: -0.13, p=0.004), and number of anti-glaucoma medications (R: -0.16, p=0.001).Conclusion:
Our findings provide evidence that plasma TAS levels are decreased in patients with glaucoma, more so in POAG and PEG than PACG, supporting the hypothesis that decreased antioxidative defense and/or increased oxidative stress may have a critical role in the pathogenesis of glaucoma.Glaucoma is a progressive optic neuropathy associated with optic nerve damage, and is one of the most leading cause of blindness worldwide.1 Elevated intraocular pressure (IOP) as a result of reduction in normal aqueous outflow is a major causal risk factor that is well supported by animal studies.2-4 Although IOP is considered a major risk factor for glaucoma,2,3 other concomitant factors affecting the pathophysiology of glaucomatous retinal ganglion cell (RGC) death include retinal ischemia,5 nutritional status,6 and oxidative stress.7 There is evidence of oxidative damage in ocular diseases, such as cataract and age-related macular degeneration.8 In addition, significant oxidative damage has been demonstrated in human trabecular meshwork (TM) cells of patients with glaucoma,7 causing elevated IOP and visual field damage.9 Furthermore, our previous studies have documented mitochondrial abnormalities10-12 (oxidative stress marker), and glutathione-S-transferase (antioxidant) gene (GST) polymorphisms to be associated with various types of glaucoma.13 It is clearly evident from the literature, and our own studies, that oxidative stress mechanisms play a critical role in the pathogenesis of glaucoma. Previous studies had demonstrated reduced total antioxidant capacity in aqueous humor and blood samples from patients with glaucoma.14-17 To evaluate the role of oxidative stress in different types of glaucoma we had previously investigated total antioxidants status (TAS) in the plasma of pseudoexfoliation glaucoma (PEG) patients,18 primary angle closure glaucoma (PACG) patients,19 and in the plasma of primary open angle glaucoma (POAG) patients.20 As an extension to these studies, here, we compare the mean TAS level among these 3 glaucoma types, and study the potential association between the TAS level and various clinical parameters important to each type of glaucoma.18-20 相似文献25.
Management of chronic heart failure in the older population 总被引:1,自引:0,他引:1
Chronic heart failure (CHF) is the leading cause of hospitalization for those over the age of 65 and represents a significant clinical and economic burden. About half of hospital re-admissions are related to co-morbidities, polypharmacy and disabilities associated with CHF. Moreover, CHF also has an enormous cost in terms of poor prognosis with an average one year mortality of 33%–35%. While more than half of patients with CHF are over 75 years, most clinical trials have included younger patients with a mean age of 61 years. Inadequate data makes treatment decisions challenging for the providers. Older CHF patients are more often female, have less cardiovascular diseases and associated risk factors, but higher rates of non-cardiovascular conditions and diastolic dysfunction. The prevalence of CHF with reduced ejection fraction, ischemic heart disease, and its risk factors declines with age, whereas the prevalence of non-cardiac co-morbidities, such as chronic renal failure, dementia, anemia and malignancy increases with age. Diabetes and hypertension are among the strongest risk factors as predictors of CHF particularly among women with coronary heart disease. This review paper will focus on the specific consideration for CHF assessment in the older population. Management strategies will be reviewed, including non-pharmacologic, pharmacologic, quality care indicators, quality improvement in care transition and lastly, end-of-life issues. Palliative care should be an integral part of an interdiscipli-nary team approach for a comprehensive care plan over the whole disease trajectory. In addition, frailty contributes valuable prognostic in-sight incremental to existing risk models and assists clinicians in defining optimal care pathways for their patients. 相似文献
26.
Vinod Kumar Abhidnya Surve Devesh Kumawat Brijesh Takkar Shorya Azad Rohan Chawla Daraius Shroff Atul Arora Ramandeep Singh Pradeep Venkatesh 《Indian journal of ophthalmology》2021,69(4):824
The peripheral retina is affected in a variety of retinal disorders. Traditional fundus cameras capture only a part of the fundus even when montaging techniques are used. Ultra-wide field imaging enables us to delve into the retinal periphery in greater detail. It not only facilitates assessing color images of the fundus, but also fluorescein angiography, indocyanine green angiography, fundus autofluorescence, and red and green free images. In this review, a literature search using the keywords “ultra-widefield imaging”, “widefield imaging”, and “peripheral retinal imaging” in English and non-English languages was done and the relevant articles were included. Ultra-wide field imaging has made new observations in the normal population as well as in eyes with retinal disorders including vascular diseases, degenerative diseases, uveitis, age-related macular degeneration, retinal and choroidal tumors and hereditary retinal dystrophies. This review aims to describe the utility of ultra-wide field imaging in various retinal disorders. 相似文献
27.
Irum Shaheen Khuram Shahzad Ahmad Camila Zequine Ram K. Gupta Andrew Thomas Mohammad Azad Malik 《RSC advances》2020,10(14):8115
Transitional metal oxide nanomaterials are considered to be potential electrode materials for supercapacitors. Therefore, in the past few decades, huge efforts have been devoted towards the sustainable synthesis of metal oxide nanomaterials. Herein, we report a synergistic approach to synthesize spherical-shaped CoMoO4 electrode materials using an inorganic–organic template via the hydrothermal route. As per the synthesis strategy, the precursor solution was reacted with the organic compounds of E. cognata to tailor the surface chemistry and morphology of CoMoO4 by organic species. The modified CoMoO4 nanomaterials revealed a particle size of 23 nm by X-ray diffraction. Furthermore, the synthesized material was scrutinized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy and energy dispersive spectroscopy. The optical band gap energy of 3.6 eV was calculated by a Tauc plot. Gas chromatography-mass spectrometry identified cyclobutanol (C4H8O) and octodrine (C8H19N) as the major stabilizing agents of the CoMoO4 nanomaterial. Finally, it was revealed that the bioorganic framework-derived CoMoO4 electrode exhibited a capacitance of 294 F g−1 by cyclic voltammetry with a maximum energy density of 7.3 W h kg−1 and power density of 7227.525 W kg−1. Consequently, the nanofeatures and organic compounds of E. cognata were found to enhance the electrochemical behaviour of the CoMoO4-fabricated electrode towards supercapacitor applications.Transitional metal oxide nanomaterials are considered to be potential electrode materials for supercapacitors. 相似文献
28.
Synthesis of primaquine glyco‐conjugates as potential tissue schizontocidal antimalarial agents 下载免费PDF全文
Chandra S. Azad Mridula Saxena Arif J. Siddiqui Jyoti Bhardwaj Sunil K. Puri Guru P. Dutta Nitya Anand Anil K. Saxena 《Chemical biology & drug design》2017,90(2):254-261
Primaquine ( PQ ) is the only drug used to prevent relapse of malaria due to P. vivax and P. ovale, by eradicating the dormant liver form of the parasite (hypnozoites). The side‐effects associated with PQ limits is uses in treatment of malaria. To overcome the premature oxidative deamination and to increase the life span of drug in the biological system, the novel glyco‐conjugates of PQ were synthesized by coupling of primaquine with hexoses in phosphate buffer. The saccharide part of the hybrid molecules thought to direct the drug to the liver, where hypnozoites resides. All the synthesized compounds were fully characterized and evaluated for their radical curative activities. The three compounds viz glucoside ( 15a ), galactoside ( 15b ) and mannoside ( 15c ) with high activity were tested for their activity in rhesus monkeys where the most active compound 15b showed twofold activity (100% radical curative activity at 1.92 mmol/kg) than the standard drug PQ diphosphate (3.861 mmol/kg). It is proposed that results from these studies may be advantageous to develop a new potent tissue schizonticide antimalarial compound. 相似文献
29.
New tick defensin isoform and antimicrobial gene expression in response to Rickettsia montanensis challenge 下载免费PDF全文
Ceraul SM Dreher-Lesnick SM Gillespie JJ Rahman MS Azad AF 《Infection and immunity》2007,75(4):1973-1983
Recent studies aimed at elucidating the rickettsia-tick interaction have discovered that the spotted fever group rickettsia Rickettsia montanensis, a relative of R. rickettsii, the etiologic agent of Rocky Mountain spotted fever, induces differential gene expression patterns in the ovaries of the hard tick Dermacentor variabilis. Here we describe a new defensin isoform, defensin-2, and the expression patterns of genes for three antimicrobials, defensin-1 (vsnA1), defensin-2, and lysozyme, in the midguts and fat bodies of D. variabilis ticks that were challenged with R. montanensis. Bioinformatic and phylogenetic analyses of the primary structure of defensin-2 support its role as an antimicrobial. The tissue distributions of the three antimicrobials, especially the two D. variabilis defensin isoforms, are markedly different, illustrating the immunocompetence of the many tissues that R. montanensis presumably invades once acquired by the tick. Antimicrobial gene expression patterns in R. montanensis-challenged ticks suggest that antimicrobial genes play a role during the acquisition-invasion stages in the tick. 相似文献
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