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31.
Madhu Poornima Mamidala Anupama Polinedi Praveen Kumar P.T.V. N. Rajesh OmSai Ramesh Vallamkonda Vrajesh Udani Nidhi Singhal Vidya Rajesh 《Research in developmental disabilities》2013,34(9):3004-3013
Incidence of Autism Spectrum Disorder (ASD) is increasing across the globe and no data is available from India regarding the risk factors of ASD. In this regard a questionnaire based epidemiological assessment was carried out on prenatal, perinatal and neonatal risk factors of ASD across 8 cities in India. A retrospective cohort of 942 children was enrolled for the study. 471 children with ASD, under age of 10, were analyzed for pre-, peri-, and neonatal factors and were compared with the observations from equal number of controls. The quality control of the questionnaire and data collection was done thoroughly and the observations were computed statistically. A total of 25 factors were evaluated by unadjusted and adjusted analysis in this study. Among the prenatal factors considered, advanced maternal age, fetal distress and gestational respiratory infections were found to be associated with ASD and had an odds ratio of 1.8. Evaluation of perinatal and neonatal risk factors showed labor complications, pre-term birth, neonatal jaundice, delayed birth cry and birth asphyxia to be associated with ASD with an odds ratio greater than 1.5. This important study, first of its kind in Indian population gives a firsthand account of the relation of pre-, peri- and neonatal risk factors on ASD from an ethnically and socially diverse country like India, the impact of which was unknown earlier. This advocates additional focused investigations on physiological and genetic changes contributed by these risk factor inducing environments. 相似文献
32.
Amulya Nidhi Shrivastava Jacob M. Kowalewski Marianne Renner Luc Bousset Annette Koulakoff Ronald Melki Christian Giaume Antoine Triller 《Glia》2013,61(10):1673-1686
β‐Amyloid (Aβ) oligomers initiate synaptotoxicity following their interaction with the plasma membrane. Several proteins including metabotropic glutamate type 5 receptors (mGluR5s) contribute to this process. We observed an overexpression of mGluR5s in reactive astrocytes surrounding Aβ plaques in brain sections from an Alzheimer's disease mouse model. In a simplified cell culture system, using immunocytochemistry and single molecule imaging, we demonstrated a rapid binding of Aβ oligomers on the plasma membrane of astrocytes. The resulting aggregates of Aβ oligomers led to the diffusional trapping and clustering of mGluR5s. Further, Aβ oligomers induced an increase in ATP release following activation of astroglial mGluR5s by its agonist. ATP slowed mGluR5s diffusion in astrocytes as well as in neurons co‐cultured with astrocytes. This effect, which is purinergic receptor‐dependent, was not observed in pure neuronal cultures. Thus, Aβ oligomer‐ and mGluR5‐dependent ATP release by astrocytes may contribute to the overall deleterious effect of mGluR5s in Alzheimer's disease. GLIA 2013;61:1673–1686 相似文献
33.
Vince B. C. Biemans Jasmijn A. M. Sleutjes Annemarie C. de Vries Alexander G. L. Bodelier Gerard Dijkstra Bas Oldenburg Mark Löwenberg Adriaan A. van Bodegraven Andrea E. van der Meulen-de Jong Nanne K. H. de Boer Nidhi Srivastava Rachel L. West Tessa E. H. Römkens Carmen S. Horjus Talabur Horje Jeroen M. Jansen C. Janneke van der Woude Jildou Hoekstra Rinse K. Weersma Fiona D. M. van Schaik Frank Hoentjen Marieke J. Pierik the Dutch Initiative on Crohn Colitis 《Alimentary pharmacology & therapeutics》2020,51(9):880-888
34.
Piyush Gupta Pooja Dewan Dheeraj Shah Nisha Sharma Nidhi Bedi Iqbal R. Kaur Ajay Kumar Bansal S.V. Madhu 《Indian pediatrics》2016,53(11):967-976
Objective
To evaluate the efficacy of single oral mega-dose of Vitamin D3 for treatment and prevention of pneumonia in underfive children.Design
Randomized, double blind, placebo-controlled trial.Setting
Tertiary-care hospital.Participants
324 children (of 980 assessed) between 6 mo-5 y age (median (IQR): 12 (7,19.8) mo) with WHO-defined severe pneumonia. Of these, 126 (39%) were vitamin D deficient (serum 25(OH)D <12 ng/mL).Intervention
100,000 IU of oral cholecalciferol (n= 162) or placebo (n= 162) in single dose, administered at enrolment.Outcome variables
Primary: Time to resolution of severe pneumonia and proportion of children having recurrence of pneumonia in next 6 months; Secondary: Change in serum levels of 25(OH)D; immunoglobulins IgA, IgG, IgM, and cathelicidin 2 weeks following supplementation; and time taken for overall resolution of illness.Results
Median (95% CI) time for resolution of severe pneumonia was 30 (29, 31) h in the vitamin D group as compared to 31 (29,33) h in the placebo group [adjusted hazard ratio (95% CI): 1·39 (1·11, 1·76); P=0·005]. The risk of recurrence of pneumonia in next 6 months was comparable in the two groups [placebo: 36/158 (22·8%); vitamin D: 39/156 (25%); RR (95% CI): 1·13 (0·67,1·90); P=0·69]. Proportion of vitamin D deficient children declined from 38% to 4% in the supplementation group, and from 41% to 33% in the placebo group, two weeks after supplementation. There was no significant effect of vitamin D supplementation on serum levels of cathelicidin, IgA and IgG. The time taken for complete recovery from pneumonia, duration of hospitalization, and fever clearance time were comparable for the two groups. No adverse event was noted related to the intervention.Conclusion
There is no robust evidence of a definite biological benefit, either for therapy or prevention, to suggest a routine megadose supplement of vitamin D3 for under-five children with severe pneumonia.35.
Context:Wound infection increases the hospital stay and adversely affects the recovery of patients. Culture and sensitivity of wound isolates help in proper diagnosis and management of these patients.Aim:To identify common bacteria causing wound infections and their antibiotic sensitivity pattern.Results:There were a total of 150 patients with infected wounds. Most common organism isolated was Pseudomonas followed by Klebsiella and Staphylococcus aureus. All of these organisms were resistant to most routine antibiotics.Conclusion:We suggest a multidisciplinary approach to wound management, rational drug use, routine microbiological surveillance of wounds and institution of hospital infection control policy.KEY WORDS: Bacteria, culture and sensitivity, wound infection 相似文献
36.
The aim of the study was to formulate a microemulsion (ME) using chitosan (CH) and the butter oil (BO) as a permeation enhancer for targeting drug to the posterior segment of the eye, via topical route. Triamcinolone acetonide (TA) was selected as the model drug since it undergoes extensive first-pass metabolism, leading to poor oral bioavailability of 23%. For optimisation of BO concentration, different ratios of TA:BO were prepared by simple physical mixing in the ratio of 1:9 to 9:1 and diffusion study was performed. MEs containing TA, TA:BO and TA CH ME were formulated by water titration method. Globule sizes of TA ME, TA:BO ME and TA CH ME were found to be 66.06?±?0.32?nm, 78.52?±?1.50?nm and 97.30?±?2.50?nm, respectively. In ex vivo diffusion studies using goats eye, TA:BO ME (31.33?±?0.46 and 33.98?±?0.23) and TA CH ME (24.10?±?0.41 and 27.00?±?0.18) showed higher percentage of drug diffusion in comparison to TA ME (13.29?±?0.41and 15.56?±?0.34) and TA solution (8.20?±?1.04 and 10.39?±?0.22) in presence and in absence of vitreous humour. Fluorescence intensity of coumarin-6 (as a marker) loaded ME with BO and CH was found to be higher, confirming their role in altering membrane permeability and facilitating coumarin-6 diffusion to the posterior chamber. Overall, it was concluded that BO enhances the bioavailability of TA across the retina, thereby proving its potential as permeation enhancer in facilitating drug delivery to the posterior segment of the eye. 相似文献
37.
Sahithi Ravuluri Rohit Bansal Nidhi Chhabra Anurag S. Rathore 《Pharmaceutical research》2018,35(7):142
Purpose
To understand non-enzymatic hydrolytic fragmentation of a monoclonal antibody therapeutic under temperature stressed conditions and investigating possible mechanism for the same.Methods
The mAb therapeutic was incubated at 50°C in phosphate buffer at pH 6.5 and fragmentation was monitored at different ionic strengths under stressed conditions. The incubated mAb was sampled at regular time intervals by analytical Size Exclusion Chromatography (SEC).Results
It was observed that 57% of the mAb product fragmented over 4 days into two fragment species – Fc-Fab and Fab with molecular weights of 97 KDa and 47 KDa, respectively, as measured by mass spectrometry (MS) and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The fragmentation rate was slow initially and then accelerated with time. No change in % aggregate level was observed in this duration, implying that degradation was primarily via fragmentation at high temperature. Kinetics of hydrolytic fragmentation was hypothesized and SEC data was fitted to estimate the kinetic rate constants. While degradation of the monomer into fragment species was non-Arrhenius with a negative activation energy, further degradation of Fab-Fc fragments into Fab or Fc fragments followed Arrhenius Law with an activation energy of 2.1 and 15.38 kcal/mol, respectively.Conclusion
High temperature (50°C) causes mAb to cleave at the hinge region to form Fab-Fc and Fab/Fc, as confirmed by dynamic light scattering, SDS-PAGE, SEC, and MS. A kinetic model for hydrolytic fragmentation has been proposed. The results are expected to assist end users in formulation development as well as in monitoring stability of biotherapeutic products.38.
39.
Nidhi S. Patel Falguni B. Tandel Yogita D. Patel Kartavya B. Thakkar 《Indian journal of pharmaceutical sciences》2014,76(6):535-540
A stability-indicating reverse phase high performance liquid chromatography method was developed and validated for cefixime and linezolid. The wavelength selected for quantitation was 276 nm. The method has been validated for linearity, accuracy, precision, robustness, limit of detection and limit of quantitation. Linearity was observed in the concentration range of 2-12 μg/ml for cefixime and 6-36 μg/ml for linezolid. For RP-HPLC, the separation was achieved by Phenomenex Luna C18 (250×4.6 mm) 5 μm column using phosphate buffer (pH 7):methanol (60:40 v/v) as mobile phase with flow rate 1 ml/min. The retention time of cefixime and linezolid were found to be 3.127 min and 11.986 min, respectively. During force degradation, drug product was exposed to hydrolysis (acid and base hydrolysis), H2O2, thermal degradation and photo degradation. The % degradation was found to be 10 to 20% for both cefixime and linezolid in the given condition. The method specifically estimates both the drugs in presence of all the degradants generated during forced degradation study. The developed methods were simple, specific and economic, which can be used for simultaneous estimation of cefixime and linezolid in tablet dosage form. 相似文献