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101.
U. C. Srivastava I. D. Sakal R. C. Maurya 《Proceedings of the National Academy of Sciences, India. Section B.》2012,82(2):307-316
The present study, based on neurohistological techniques (Golgi impregnation), focuses on the morphological and numerical changes in the dendritic spines of neuronal classes of the cerebral cortex in Calotes versicolor. The cerebral cortex in reptiles occupies the roof of the cerebral hemisphere and is divided into four regions viz. medial, dorsomedial, dorsal and lateral cortex. Using different characteristics such as criteria of location, dendritic tree pattern, dendritic spine covering and soma shape different neuronal types have been distinguished in the cell layer-II of medial, dorsomedial, dorsal and lateral cortex. The dendritic diameter, spine length and diameter of spine head show almost uniform pattern in all cortical regions except being slightly higher in case of the neurons of dorsomedial cortex. The multipolar and pyramidal neurons show higher dendritic diameter, spine length, spine head diameter and dendritic spine density in comparison to other neurons. The density of these neurons acts as the indicator of high or low activity of a particular region. 相似文献
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Nishi Srivastava 《生物医学研究杂志》2014,28(4):328-331
Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distributed in Central and East Asia with about 30 species reported worldwide. It grows at a range of altitudes from the Khasia hills at 400 feet to the temperate Himalayas from Kashmir to Bhutan at 7,000-10,000 feet. Its distribution over a wide range of altitudinal zones makes it a good candidate for studying variations in its metabolic profiles under different climatic conditions. Bergenin (C-glycoside of 4-O-methyl gallic acid) has been identified as a potent active secondary metabolite in Bergenia and other therapeutically active constituents including, among others, gallic acid (3,4,5 trihydroxybenzoic acid), (+) catechin, and gallicin (Fig. 1). 相似文献
104.
Ritesh K. Srivastava Samer Zaid Kaylani Nayf Edrees Changzhao Li Sarang S. Talwelkar Jianmin Xu Komaraiah Palle Joseph G. Pressey Mohammad Athar 《Oncotarget》2014,5(23):12151-12165
Rhabdomyosarcoma (RMS) typically arises from skeletal muscle. Currently, RMS in patients with recurrent and metastatic disease have no successful treatment. The molecular pathogenesis of RMS varies based on cancer sub-types. Some embryonal RMS but not other sub-types are driven by sonic hedgehog (Shh) signaling pathway. However, Shh pathway inhibitors particularly smoothened inhibitors are not highly effective in animals. Here, we show that Shh pathway effectors GLI1 and/or GLI2 are over-expressed in the majority of RMS cells and that GANT-61, a specific GLI1/2 inhibitor dampens the proliferation of both embryonal and alveolar RMS cells-derived xenograft tumors thereby blocking their growth. As compared to vehicle-treated control, about 50% tumor growth inhibition occurs in mice receiving GANT-61 treatment. The proliferation inhibition was associated with slowing of cell cycle progression which was mediated by the reduced expression of cyclins D1/2/3 & E and the concomitant induction of p21. GANT-61 not only reduced expression of GLI1/2 in these RMS but also significantly diminished AKT/mTOR signaling. The therapeutic action of GANT-61 was significantly augmented when combined with chemotherapeutic agents employed for RMS therapy such as temsirolimus or vincristine. Finally, reduced expression of proteins driving epithelial mesenchymal transition (EMT) characterized the residual tumors. 相似文献
105.
Retention and HIV seroconversion among drug users on methadone maintenance treatment in Yunnan,China
Y-P. Chang L. Duo A. M. V. Kumar S. Achanta H-M. Xue S. Satyanarayana R. Ananthakrishnan S. Srivastava W. Qi S-Y. Hu 《Public Health Action》2014,4(1):28-34
Setting: Thirteen methadone maintenance treatment (MMT) clinics across Yunnan, the province with the highest human immunodeficiency virus (HIV) burden in China.Objectives: To determine, among HIV-negative participants on MMT, the proportion lost to follow-up (defined as those who missed the 6-monthly follow-up examination), factors associated with loss to follow-up (LFU), HIV seroconversion rate and factors associated with seroconversion.Design: Prospective cohort study from October 2008 to April 2011. All participants were administered a pre-tested structured questionnaire to capture associated factors and offered HIV testing every 6 months. χ2 test and log-binomial regression were used for data analysis.Results: Of 1146 participants, 541 (47%) were lost to follow-up in 2.5 years. Factors associated with higher LFU proportion include <6 months of previous MMT, inconvenient location of the MMT clinic and average methadone dose ⩽60 mg/day, with adjusted relative risks (RRs) of respectively 1.4 (95%CI 1.2–1.5), 1.2 (95%CI 1.0–1.4) and 1.1 (95%CI 1.0–1.3). The overall HIV seroconversion rate was 6.6 (95%CI 3.7–11.0) per 1000 person-years. Not living with a partner contributed to higher HIV rates, with an adjusted RR of 3.6 (95%CI 1.0–12.8).Conclusion: The retention rate of MMT participants in Yunnan was not satisfactory. Decentralising service delivery in the community and making directly observed treatment more convenient has the potential to improve retention. 相似文献
106.
N. Sreeramulu F.F. Banyikwa V. Srivastava 《International journal of food sciences and nutrition》2013,64(4):215-219
SummaryThe ascorbic acid content of 12 varieties of leafy vegetables was determined. Infresh leaves, the ascorbic acid content varied from 276 mg/100 g fresh weight inTrigonella foenum-graecum to 58 mg/100 g in Polygonum plebeium.The ascorbic acid content in the leafy vegetables stored open (uncovered) inthe laboratory (25-35 °C) for 24 hours decreased, the loss varying from 28.0 to 48.3 per cent. Contrary to this, the loss of ascorbic acid during storage in theleaves covered with a wet cloth was much less, ranging from 1.6 to 10.4 per cent.Estimations of moisture and ascorbic acid content of T: foenum-graecum andP.plebeium at different intervals during wilting until the leaves reached the airdrystate indicated a positive correlation of ascorbic acid content with the mois-turecontent of the leaves. 相似文献
107.
Tarun Shankar Choudhary Akanksha Srivastava Ranadip Chowdhury Sunita Taneja Rajiv Bahl Jose Martines Maharaj Kishan Bhan Nita Bhandari 《Maternal & child nutrition》2019,15(4)
Burden and risk factors for wasting in the first 6 months of life among Indian children are not well documented. We used data from India's National Family Health Survey 4 to estimate the prevalence of severe wasting (weight for length < ‐3 SD) among 18,898 infants under 6 months of age. We also examined the association of severe wasting with household, maternal, and child‐related factors using multivariable logistic regression analysis. Prevalence of severe wasting among infants less than 6 months of age was 14.8%, ranging from 3.5 to 21% across states. Low birth weight (<2,500 g; adjusted odds ratio [AOR] 1.40, 95% CI [1.19, 1.65]), nonutilization of supplementary nutrition by mother during lactation (AOR 1.23, 95% CI [1.05, 1.43]), and anthropometric assessment during summer (AOR 1.37, 95% CI [1.13, 1.65]) and monsoon months (AOR 1.53, 95% CI [1.20, 1.95]) were associated with higher odds of severe wasting. Infants aged 2 to 3 months (AOR 0.78, 95% CI [0.66, 0.93]) and 4 to 5 months (AOR 0.65, 95% CI [0.55, 0.73]) had lower odds of severe wasting as compared with the 0‐ to 1‐month category. This analysis reveals a high burden of severe wasting in infants less than 6 months in India. Preventive interventions must be targeted at reducing low birth weight due to fatal growth restriction and prematurity. Appropriate care practices at facilities and postdischarge with extra attention to those born small and sick can prevent further deterioration in nutritional status. 相似文献
108.
Screening for subclinical subclavian artery stenosis before coronary artery bypass grafting: Should we do it? 下载免费PDF全文
Ali Abdul Jabbar MD Justin Houston MD Mark Burket MD Zachary J. Il'Giovine MD Bal K. Srivastava MD Ajay Agarwal MD 《Echocardiography (Mount Kisco, N.Y.)》2017,34(6):928-933
Atherosclerotic subclavian artery disease is detected in about 5% of patients referred for coronary artery bypass (CABG) surgery. The internal mammary artery, a branch of the subclavian artery, is the most frequently utilized graft to restore coronary circulation because of its longevity. Stenosis or occlusion of the subclavian artery can cause retrograde blood flow in the ipsilateral internal mammary artery, known as “steal,” compromising coronary circulation supplied by the graft. Steal may be asymptomatic or may result in symptoms of myocardial ischemia. Symptomatic subclavian artery stenosis post bypass is referred to as coronary subclavian steal syndrome post‐CABG. The incidence is not well defined, and the benefits of screening patients referred for CABG are not known. Despite the various modalities available to detect subclavian artery stenosis, current guidelines fail to provide guidance about screening high‐risk patients for this entity. Detection of subclavian artery disease prior to CABG can reduce complications posed by post‐mammary artery graft cardiac ischemia. This review discusses the utility of preoperative subclavian artery screening prior to CABG. 相似文献
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110.
Manish Bansal Gauraw Kumar Srivastava Narmada Prasad Gupta 《The journal of sexual medicine》2019,16(12):1912-1921
IntroductionHigh-sensitivity C-reactive protein (hs-CRP), a marker of inflammation, is known to be elevated in patients with erectile dysfunction (ED). However, its role in predicting therapeutic response to phosphodiesterase-5 inhibitors is incompletely understood.AimThe aim of this study was to understand the relationship among hs-CRP, mechanism of ED, and therapeutic response of ED to tadalafil, a phosphodiesterase-5 inhibitor.MethodsA total of 282 men (mean age 36.6 ± 12.0 years) with ED were included. All subjects underwent detailed evaluation, including estimation of a 6-item abbreviated version of the International Index of Erectile Function (IIEF-6) score, penile Doppler studies, and measurement of hs-CRP. IIEF-6 scoring and hs-CRP measurement were repeated after 6 weeks of tadalafil therapy (10 mg/day). The patients were categorized into vasculogenic and nonvasculogenic ED groups based on penile Doppler findings.Main Outcome MeasureThe main outcome measure was the therapeutic response to tadalafil, in relation to the mechanism of ED and hs-CRP levels.ResultsVasculogenic ED was much less common (23.8% of the subjects) than non-vasculogenic ED. Subjects with vasculogenic ED were older, had higher prevalence of cardiovascular risk factors, had more severe (mean IIEF-6 score 9.2 ± 4.6 vs 14.8 ± 4.7; P < .001) and longer duration ED, and responded less favorably to therapy (response rate 10.4% vs 75.0%; P < .001). Those showing improvement with tadalafil had lower hs-CRP at baseline (median 1.5 mg/L [interquartile range 0.9?2.3] vs 2.0 mg/L [interquartile range 1.1?3.1; P = .034]) and had proportionately greater reduction in its level. However, on multivariate analysis, only shorter duration of ED (P = .008), non-vasculogenic origin (P = .025), and higher IIEF-6 score at baseline (P = .013) were independent predictors of response to treatment.Clinical ImplicationsSerum hs-CRP is elevated in patients who are less likely to respond to vasodilator therapy but does not have an independent predictive value for this purpose.Strengths & LimitationsThis is the largest study to evaluate the relationship among the mechanism of ED, serum hs-CRP level, and therapeutic response of ED to tadalafil. All patients underwent a penile Doppler study to characterize the type of ED. The limitations were nonrandomized nature of the study and nearly 22% dropout rate.ConclusionSerum hs-CRP level is higher in vasculogenic ED compared with non-vasculogenic ED, and is associated with poorer response to tadalafil therapy. However, this association is not independent of underlying risk factors and mechanism of ED.Jamaluddin, Bansal M, Srivastava GK, et al. Role of Serum High-Sensitivity C-Reactive Protein as a Predictor of Therapeutic Response to Tadalafil in Patients With Erectile Dysfunction: A Prospective Observational Study. J Sex Med 2019;16:1912–1921. 相似文献