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1.
World Allergy Organ J ; 17(6): 100916, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38974947

RESUMEN

Background: There is paucity of reliable epidemiological data regarding the burden of food allergy in most developing countries, including India. Objective: To provide current estimates of the prevalence and distribution of food allergy among urban and rural school children aged 6-14 years in Delhi and the National Capital Region (NCR) of Khekra in India. Methods: A cross-sectional study was conducted from January 2022 to February 2023 to enroll school children, 6-14 years, from select urban and rural schools in Delhi and NCR. A questionnaire consisting of questions focused on household environment, early life factors, and pediatric food allergy characteristics was administered by a trained medical researcher to collect parent-proxy data. Univariate statistics were used to describe frequencies, percentages, and 95% confidence intervals for survey items. Results: The estimated prevalence of parent-reported food allergy was 0.8% (95% CI: 0.4-1.5; urban: 0.4%, 95% CI: 0.1-1.1; rural: 1.7%, 95% CI: 0.7-3.5). Fruits such as mango (0.3%, 95% CI: 0.1-0.9), strawberry (0.1%, 95% CI: 0.0-0.7), orange (0.1%, 95% CI: 0.0-0.7), and custard apple (0.1%, 95% CI: 0.0-0.7) were reported only by urban children, while rural children reported yogurt (0.6%, 95% CI: 0.1-1.8) and wheat (0.3%, 95% CI: 0.0-1.3). Both groups reported brinjal (also known as eggplant) and banana, 0.1% (95% CI: 0.0-0.7) of urban and 0.3% (95% CI: 0.0-1.3) of rural, respectively. Overall, commonly reported clinical symptoms were diarrhea and/or vomiting (100%, 95% CI: 76.2-100), abdominal pain (88.9%, 95% CI: 58.6-98.8), and rash/itchy skin (66.7%, 95% CI: 34.8-89.6). Among children with parent reported food allergy, 66.7% (95% CI: 34.8-89.6) of food allergies were physician diagnosed, of which 33.3% were diagnosed via history alone (95% CI:7.7-71.4) while 66.7% (95% CI: 28.6-92.3) were confirmed via skin prick test and/or blood test. Conclusion: The overall prevalence of food allergy is very low in Delhi and Khekra, India. Future work should focus on elucidating the complex interplay of early-life, environmental, genetic, and lifestyle factors to understand the reasons for India's low food allergy burden and improve epidemiological clues to prevention for the nations with higher disease burden.

2.
J Family Med Prim Care ; 13(5): 1863-1867, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38948563

RESUMEN

Introduction: Flow-mediated dilation (FMD) of the brachial artery is an ultrasonography test that assesses the endothelial response to reactive hyperemia. The aim of this study was to assess the changes in FMD in preeclamptic pregnant patients and compare them with normotensive pregnant females. Methods: An analytical cross-sectional comparative study was conducted in the Department of Obstetrics and Gynaecology at King George's Medical University (KGMU) after obtaining ethical approval. A total of 110 normotensive and 100 preeclamptic patients were recruited for the study. Using a Toshiba Ultrasound Machine with a 7-12 MHz probe, the baseline diameter of the brachial artery D1 was measured. Afterward, the cuff of the sphygmomanometer was placed distally on the forearm and it was inflated up to ≥250 mm of Hg pressure and later slowly deflated. At 90th seconds after cuff deflation, the mean of three measurements of vessel caliber (D2) was obtained. The FMD% was obtained by the following equation: FMD (%) = [(D2 - D1)/D1] ×100, where D1 = basal diameter and D2 = post-occlusion diameter. All patients were followed till delivery for maternofetal outcome. Results: FMD% was significantly lower in the preeclampsia group, and it went on decreasing with increasing severity of preeclampsia. At the cutoff of 9.4 for FMD%, its sensitivity for the prediction of preeclampsia was 65.3%, specificity was 89.3%, positive predictive value (PPV) was 94%, and negative predictive value (NPV) was 50%. Discussion: FMD is a noninvasive test, and it gets decreased before clinical signs of preeclampsia, so it can be used as a predictor of preeclampsia.

3.
J Family Med Prim Care ; 13(1): 265-270, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38482325

RESUMEN

Objective: Vaginal pH has been suggested to be one of the causative factors, responsible for variation in prostaglandin efficacy for induction of labour. The purpose of this study was to analyse the effect of vaginal douching with normal saline before insertion of dinoprostone vaginal insert for induction of labour. Methods: This randomised controlled study was done in the Department of Obstetrics and Gynaecology for a period of 1 year. Using a computer-generated random number table, subjects were allocated in two groups. In group A (study group), vaginal douching was done with 20 cc of sterile 0.9% NaCl and vaginal pH was again measured with pH paper strips just before inserting dinoprostone pessary. Dinoprostone pessary was inserted without douching in group B (control group). Results: There was a significant increase in the vaginal pH after douching with normal saline (4.91 vs 5.52, P < 0.001). Mean intrinsic vaginal pH (pH before inserting dinoprostone insert) in women who delivered vaginally was significantly higher than that of the women who had a caesarean section (5.10 vs 4.63, P < 0.001). Time interval between dinoprostone insertion to active phase of labour, duration of active phase of labour, time interval between dinoprostone insertion, and complete cervical dilatation and mode of delivery were not significantly different between the two groups. Conclusion: Although douching with normal saline increases vaginal pH, douching does not help in increasing the chances of vaginal delivery because it gives a transient effect. Rather, it is intrinsic vaginal pH, which is a better decisive factor for successful vaginal delivery.

4.
Indian J Med Res ; 158(4): 423-431, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38006345

RESUMEN

BACKGROUND OBJECTIVES: The World Health Organization (WHO) has endorsed thermal ablation (thermocoagulation) as an efficient and safe modality for treatment of cervical pre-cancer lesions. More evidence is being looked up by WHO through rigorous studies for health delivery models using screen-and-treat strategies incorporating thermal ablation and studies comparing it against the conventional standard modality cryotherapy. The objective of this study was to assess the acceptability of thermal ablation both among the providers and clients and compare the same with cryotherapy. METHODS: A randomized control trial was conducted for one year from September 2019 to October 2020 after obtaining ethics approval. Computer-generated random number table was used for randomization, and eligible candidates were divided into two groups following informed consent. Women with visual inspection with acetic acid (VIA) positive cervical lesions in Group A received cryotherapy and Group B received thermal ablation. After the procedure, the acceptability of the provider and the client were assessed using the International Agency for Research on Cancer-validated questionnaire for both the procedures. Immediate side effects and problems at six weeks and at six months were assessed as well. Efficacy was decided by the absence of VIA positivity at six months. RESULTS: The overall VIA positivity in this study was 11.8 per cent. Thermal ablation (thermocoagulation) had better provision and client acceptability than cryotherapy (significant difference). The efficacy of thermal ablation was 97.6 per cent, while, it was 92 per cent for cryotherapy (not significant). INTERPRETATION CONCLUSIONS: In the context of screen-and-treat programme in settings such as India, thermal ablation appears to be a better method of treatment than cryotherapy for cervical pre-cancerous lesions particularly in terms of better provision and client acceptability.


Asunto(s)
Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Humanos , Ácido Acético , Proyectos Piloto , Displasia del Cuello del Útero/cirugía , Crioterapia/métodos , Neoplasias del Cuello Uterino/cirugía , Electrocoagulación
5.
J Obstet Gynaecol India ; 72(5): 396-401, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36458060

RESUMEN

Purpose of the study: Placental growth factor (PLGF) is an angiogenic factor in pregnancy. To find out correlation of plasma levels of placental growth factor in first trimester of pregnancy in Indian women who develop maternal and perinatal adverse outcomes was the aim of the study. Methods: A prospective longitudinal noninterventional study was done in the department of Obstetrics and Gynecology after obtaining ethics approval. After enrolling patients in the first trimester (11 weeks to 13 weeks 6 days), a questionnaire was filled for demographic characteristics. Uterine artery doppler was done for every patient and blood sample (5 ml) was taken by venu puncture of median cubital vein. Serum levels of PLGF were measured by enzyme linked immunosorbent assay using Thermo Scientific Pierce Human PLGF kit (Thermo Fisher Scientific, Inc., Waltham, MA, USA). Patients were followed for their whole antenatal period and delivery outcomes. Results: Incidence of preeclampsia in our study was 9.3% (15/161) and fetal growth restriction (FGR) was 19.8% (32/161). Neither BMI nor nulliparity was found to have statistically significant correlation with development of preeclampsia. However, history of preeclampsia was found to be significant risk factor for prediction of preeclampsia (p value < 0.04). Plasma levels of PLGF were significantly lower in preeclampsia and FGR group and this difference was statistically significant (p value < 0.04). 7.5% still born occurred in complicated group and 10% needed NNU/NICU admission in this group. Conclusion: Measuring PLGF levels in first trimester of pregnancy can help in prediction of preeclampsia and FGR.

6.
J Cancer Res Ther ; 18(3): 603-611, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35900529

RESUMEN

Background: Less literature is available on the performance of thermocoagulation for treatment of premalignant cervical lesions and its comparison with cryotherapy from low- and middle-income countries like India. Materials and Methods: : A prospective randomized controlled study was done in the Department of Obstetrics and Gynecology from August 2018 to September 2019 after obtaining ethical clearance from Institutional Review Board (Reg no: ECR/262/Inst/Up/2013/RR/16) Ref no: 278/Ethics/R. cell-18). A total of 68 women with Visual inspection with acetic acid (VIA) positive cervical lesion were randomized into two groups. Group A was treated with cryotherapy and Group B was treated with thermocoagulation. Estimates of cure, adverse effects or complications were presented as frequencies, percentages, and mean ± standard deviation. Results: Out of 667 patients, 624 patients underwent VIA testing among which 68 were VIA positive (10.89%, 68/624). The efficacy of thermocoagulation was 93.54% and that of cryotherapy was 90.32%. Immediate side effects were significantly lesser in thermocoagulation group (P = 0.008) in comparison to cryotherapy. Conclusion: Thermocoagulation is better treatment modality than cryotherapy for VIA-positive cervical lesions may not be in terms of efficacy but definitely in terms of patient comfort and safety.


Asunto(s)
Ácido Acético , Neoplasias del Cuello Uterino , Crioterapia/efectos adversos , Electrocoagulación , Femenino , Humanos , Embarazo , Estudios Prospectivos , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/terapia
7.
J Family Med Prim Care ; 11(5): 2155-2161, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35800491

RESUMEN

Background: Pregnancy-related acute kidney injury (PRAKI) has bimodal distribution. The rates of maternal mortality and perinatal mortality in patients with PRAKI have increased. The aim of this study was to evaluate magnitude of PRAKI in North Indian women and to assess morbidity, mortality, and outcomes in patients who received renal replacement therapy. Materials and Methods: This prospective observational study was carried out in the Department of Obstetrics and Gynaecology, in collaboration with nephrology. A total of 150 women suffering from PRAKI were recruited and total 98 obstetrics AKI, requiring renal replacement therapy, classified as per KDIGO guidelines 2012 were enrolled for dialysis. Six patients were lost to follow up before final analysis. Haemodialysis was carried out by B. Brawn machine. Results: Approximately 82% cases of PRAKI diagnosed in postpartum period. Mean cycles of dialysis was 9.06 ± 7.75 approximately half of the females required 1-5 cycles of dialysis. Higher percentages of maternal deaths were observed within 1-5 cycles of dialysis. Women received dialysis after 72 h showed increased chances of partial recovery. After 3 months of follow-up, rate of complete recovery was significantly higher in Stage I (100%) and Stage II (84.6%) PRAKI while rate of partial recovery and deaths were significantly higher in Stage III PRAKI (37.3%). Stage of AKI, baseline K+ levels, treatment modality, duration of ICU stay and use of Vasopressure showed significant association with adverse outcome. Conclusion: Higher percentages of deaths were observed in those who referred late and delay in initiation of dialysis and it was observed within 1-5 cycles of dialysis.

8.
Gynecol Minim Invasive Ther ; 11(1): 36-40, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35310127

RESUMEN

Objectives: Diagnosis of ectopic pregnancy (EP) needs high index of clinical suspicion. If EP is timely diagnosed and timely intervened, i.e., before rupture, it may cause reduction of serious morbidity and mortality. We aimed to analyze the profile of patients of ectopic pregnancies and their outcome. Materials and Methods: The sample for this retrospective cross-sectional study was derived from the database from January 2017 to December 2020. Data from outdoor patient registers, case record files, discharge summaries and hospital admission/discharge registers were screened. Parameters age, parity, risk factors, clinical presentation, per-operative findings, and maternal outcome in terms of morbidity and mortality were assessed. Results: Totally 27,525 deliveries occurred during the study period of 3 years, of which 640 were ectopic pregnancies, i.e., 2.3%. Out of 640, 415 (64.8%) were acute ruptured ectopic pregnancies, 62 (9.6%) were chronic ruptured pregnancies, and 163 (25.4%) patients were unruptured ectopic pregnancies. The mean age was 28.67 years (range: 29.5-27.8). The most common site of rupture was ampullary (54%, 225/415). 14.8% (95/640) of cases were in hemorrhagic shock out of total ectopic patients, and in ruptured group, they comprised 22.8% (95/415). Success for medical management with single-dose methotrexate in our study was 90.2% (147/163). Conclusion: Pelvic inflammatory disease and history of induced abortion were found to be the most important etiological factor in ectopic pregnancies. Comprehensive clinical examination is 100% sensitive in diagnosis of EP. In ultrasound, the presence of adnexal mass is the most common finding which is additive to clinical findings and not substitute. Although multiple management options are available, best outcome is attained if management of EP is done at earliest without any delay.

9.
BMJ Case Rep ; 15(3)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35232732

RESUMEN

Cervical deciduosis refers to the condition in which ectopic decidual changes take place in the cervix. It is mostly asymptomatic but sometimes may have various clinical presentations. In our case, patient had a rare clinical presentation of cervical deciduosis, in the form of an antepartum haemorrhage at 32 weeks. On examination, there were multiple friable lesions measuring 5-15 mm in size on both the lips of the cervix and it was very much simulating to malignancy, so biopsy was done. However, biopsy led to uncontrolled bleeding and finally the patient required premature lower segment caesarean section. Both mother and baby were well. Biopsy report was diagnostic of cervical deciduosis. On follow-up at 6 weeks post partum, the cervix was found to be absolutely healthy. Since, cervical deciduosis is a benign condition which gets resolved 4-6 weeks post partum. So, keeping differential diagnosis of cervical deciduosis in mind is very important to avoid unnecessary cervical biopsies during pregnancy. And patient with suspicion of cervical deciduosis should be followed up postpartum strictly.


Asunto(s)
Cuello del Útero , Complicaciones del Embarazo , Cuello del Útero/patología , Cesárea , Decidua/patología , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/diagnóstico , Hemorragia Uterina/etiología
10.
Phys Chem Chem Phys ; 23(15): 9561-9570, 2021 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-33885086

RESUMEN

Inspired by the recent experimental reports on boron containing compounds to be active and biomimetic for carbon capture, we report the mechanistic details of CO2 hydration activities of boronic acids using density functional theory calculations. Four boronic acids were analyzed, viz., [3-methyl-6-(1H-pyrazol-1-yl)phenyl]boronic acid, 3-aminophenylboronic acid, 2,6-dibromophenylboronic acid and 2,6-bis(trifluoromethyl)phenylboronic acid. Free energy landscapes were developed for the hydration reaction. 2,6-Dibromophenylboronic acid showed the highest turnover frequency. Computational NMR and FTIR spectra for various intermediates of the reaction were analyzed and compared with experimental spectra. The energetics as well as the spectral analyses confirmed the biomimetic mechanism for CO2 hydration over all the boronic acid catalysts under investigation.

11.
Comput Biol Chem ; 86: 107236, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32220810

RESUMEN

Nanoscopic properties of TiO2 augmented with its physicochemical properties and biocompatibility make it a material interest in the biomedical field. Efficient methods to design of such materials require a thorough understanding of associated nano-bio interfaces. In the present study, density functional theory calculations were performed to study the interactions of arginine, cysteine and guanine with a nano-TiO2 cluster. Different configurations were sampled for the adsorption of arginine, cysteine and guanine to probe the nano-bio interface via the interaction of various functional groups present on biomolecules. Adsorption energies for arginine, cysteine and guanine were in a range of -25.0 to -57.6, -12.1 to -29.6 and -45.6 to -58.7 kcal/mol, respectively. From the change in adsorption energies and free energies, interaction of amino acids with carboxylic (COOH), thiol (SH) and amine (NH2) groups while the interaction of the nucleobase via O bonded to C and N of purine ring was found to be essential for thermodynamically stable and energetically favorable states. Density of states analysis also disclosed the prominent interactions of the biomolecules with the nano-TiO2 cluster. Decrease in band gaps on adsorption of the biomolecules was a pertinent phenomenon indicating the strong chemical interactions of the biomolecules with the nanoscopic TiO2 chosen for analysis in this study.


Asunto(s)
Arginina/química , Cisteína/química , Guanina/química , Nanopartículas/química , Titanio/química , Adsorción
13.
J Cancer Res Ther ; 15(6): 1338-1344, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31898670

RESUMEN

OBJECTIVE: The aim of good management for cancer survivors should not be limited to only clinical care, but rather it should also include best quality of life (QOL). The objective of this study was to find out various factors affecting QOL in cervical cancer patients so that by modifying these factors, the best QOL can be provided to them. MATERIALS AND METHODS: This was a prospective cohort study conducted in the Department of Obstetrics and Gynaecology and Department of Radiotherapy, King George's Medical University (KGMU), Lucknow, from May 2015 to July 2016. The cases were selected from patients visiting the outpatient department or who were admitted to the Department of Obstetrics and Gynaecology and Department of Radiotherapy, KGMU. The data information was collected in the form of face-to-face interview using European Organization for Research and Treatment of Cancer general cancer QOL Score 30 (EORTC QLQ C-30) and EORTC QOL questionnaire cervical cancer module (QLQ CX-24) questionnaire. RESULTS: QOL was assessed in 85 patients. Health-related QOL was separately studied in terms of overall general QOL and cancer cervix-specific QOL, and various factors affecting QOL were studied by multivariate analysis. CONCLUSION: Education, tobacco use, degree of differentiation of tumor, and size of tumor were the independent factors found to have statistically significant effect on QOL of cervical cancer survivors.


Asunto(s)
Calidad de Vida , Neoplasias del Cuello Uterino/epidemiología , Adulto , Anciano , Supervivientes de Cáncer , Análisis Factorial , Femenino , Humanos , Persona de Mediana Edad , Análisis Multivariante , Evaluación del Resultado de la Atención al Paciente , Estudios Prospectivos , Vigilancia en Salud Pública , Encuestas y Cuestionarios , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/terapia
14.
BMJ Case Rep ; 20182018 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-30077979

RESUMEN

A 14-year-old girl presented with increasing cyclical pain, scanty menses, pelvic mass and absence of the left kidney. With both radiological and clinical examinations (examination under anaesthesia), diagnosis of bicornuate uterus with single cervix could be made while on laparotomy, and it turned out to be uterine didelphys, with one cervix obscured by blind hemivagina with haematometra and haematocolpos in the left horn, for which hemihysterectomy was done. Post procedure the patient was relieved of cyclical pain and is menstruating properly.


Asunto(s)
Cuello del Útero/anomalías , Anomalías Urogenitales/diagnóstico , Útero/anomalías , Vagina/anomalías , Anomalías Múltiples , Adolescente , Cuello del Útero/cirugía , Diagnóstico Diferencial , Femenino , Hematocolpos/complicaciones , Hematómetra/complicaciones , Humanos , Histerectomía/métodos , Riñón/anomalías , Laparotomía/métodos , Tomografía Computarizada por Rayos X , Ultrasonografía , Anomalías Urogenitales/cirugía , Útero/cirugía , Vagina/cirugía
15.
BMJ Case Rep ; 20182018 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-30042106

RESUMEN

Acute retention of urine in pregnancy is an emergency, since it can lead to loss of pregnancy besides other dire complications. Gartner's abscess is an extremely rare cause for this condition. We present a case of a 23-year-old primigravida woman who presented to us at 24 weeks of pregnancy with acute retention of urine. After clinical and radiological evaluation, a large Gartner's abscess was found to be the cause. Per vaginal drainage of the abscess was not attempted because insertion of transvaginal probe was extremely painful for the patient, and the abscess was located high up in the anterior fornix. Transabdominal approach under sonographic guidance was used for the drainage of the abscess. Careful aspiration of the abscess, avoiding injury to the placenta, fetus and maternal bladder, revealed 60 cc of frank pus. The patient was given injection hydroxyprogesterone caproate and antibiotics in the preprocedure period. Antibiotics were continued in the postprocedure period, and she was discharged at 26 weeks of pregnancy in satisfactory condition.


Asunto(s)
Absceso/diagnóstico , Complicaciones Infecciosas del Embarazo/diagnóstico , Ultrasonografía Prenatal , Enfermedades Vaginales/diagnóstico , Absceso/complicaciones , Absceso/diagnóstico por imagen , Absceso/cirugía , Diagnóstico Diferencial , Drenaje , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico por imagen , Complicaciones Infecciosas del Embarazo/cirugía , Segundo Trimestre del Embarazo , Ultrasonografía Intervencional , Retención Urinaria/etiología , Enfermedades Vaginales/complicaciones , Enfermedades Vaginales/diagnóstico por imagen , Enfermedades Vaginales/cirugía , Adulto Joven
16.
BMJ Case Rep ; 20182018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29444799

RESUMEN

We present a case of a 28-year-old woman second gravida with a full-term pregnancy who presented to us in active phase of labour with third degree uterovaginal prolapse complicated by entrapment of fetal head by dystocia of cervix and fetal distress. Patient was immediately shifted to the operation theatre and prompt delivery was conducted by giving Duhrssen's incision on the highly vascular, oedematous prolapsed cervix. The outcome was an alive and healthy male baby. Duhrssen's incision was stitched with minimal blood loss. Postnatal management included antibiotics and daily intravaginal packing. Patient was discharged along with the baby in satisfactory condition.


Asunto(s)
Distocia/cirugía , Prolapso Uterino/cirugía , Adulto , Femenino , Sufrimiento Fetal/cirugía , Humanos , Recién Nacido , Masculino , Embarazo , Resultado del Embarazo , Prolapso Uterino/complicaciones
17.
Phys Chem Chem Phys ; 19(13): 8757-8767, 2017 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-28220172

RESUMEN

Electronic structural analyses of hydrogen terminated metal doped carbon nanotube/graphene (M-CNT/Gr, MN3-CNT/Gr, M = Ru/Rh) and ruthenium cluster decorated carbon nanotube/graphene (Ru4-CNT/Gr) were carried out for examining the biomimetic catalytic activity towards CO2 hydration reaction. The carbonic anhydrase action was followed for the reaction of CO2 with H2O resulting in a bicarbonate ion and a proton. All the catalysts were found to be active for CO2 hydration and the mechanism proved them to be biomimetic. Interconversion of CO2 to a HCO3- ion took place with five elementary steps viz. OH- formation by H2O dissociation, linear CO2 complexation, CO2 bending by nucleophilic attack of an OH- ion over CO2, HCO3- ion formation by intramolecular proton migration and HCO3- ion displacement by H2O addition. Free energy landscapes over the catalysts were developed for CO2 hydration reaction. The activation energies of H2O dissociation and CO2 bending were observed to be substantially smaller over Ru4-CNT when compared to those over the other catalysts. Ru4-CNT was found to be the best catalyst for CO2 hydration with the rate limiting step being HCO3- ion formation.

18.
ACS Omega ; 2(10): 7039-7047, 2017 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-31457286

RESUMEN

An efficient, cost-effective, and earth-abundant catalyst that could drive the production of hydrogen from water without or with little external energy is the ultimate goal toward hydrogen economy. Herein, nanoplates of tungsten oxide and its hydrates (WO3·H2O) as promising electrocatalysts for the hydrogen evolution reaction (HER) are reported. The square-shaped and stacked WO3·H2O nanoplates are synthesized at room temperature under air in ethanol only, making it as a promising green synthesis strategy. The repeated electrochemical cyclic voltammetry cycles modified the surface of WO3·H2O nanoplates to WO3 as confirmed by X-ray photoelectron and Auger spectroscopy, which leads to an improved HER activity. Hydrogen evolution is further achieved from distilled water (pH 5.67) producing 1 mA cm-2 at an overpotential of 15 mV versus the reversible hydrogen electrode. Moreover, WO3·H2O and WO3 nanoplates demonstrate excellent durability in acidic and neutral media, which is highly desirable for practical application. Improved hydrogen evolution by WO3(200) when compared to that by Pt(111) is further substantiated by the density functional theory calculations.

19.
Hum Fertil (Camb) ; 20(1): 43-47, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27804310

RESUMEN

In this prospective randomized parallel group study, subjects with a pregnancy of less than 63 d were randomized to receive either (i) 200 mg oral mifepristone plus 400 µg misoprostol per vaginally concurrently (group A); (ii) or the administration of misoprostol after 48 h (group B). Transvaginal sonography was performed on the 14th day of misoprostol administration to confirm complete abortion. The primary outcome was to compare the rates of complete abortion in two groups. Secondary outcomes were to compare induction abortion interval, side effects and compliance. A total of 200 subjects included in the study were randomized into groups A and B (100 each). Both the groups were comparable for age, parity, gestational age and history of previous abortion. The complete expulsion rate in group A was 96% (95% confidence interval (CI) 95.1-98.2%) and group B was 95% (95% CI 93.0-96.8%) (p > 0.100). A gestational age of more than 56 d was found to predict failure of treatment in both groups. The adverse effect profile in the two groups was the same. Efficacy of concurrent mifepristone and misoprostol in combination is similar to that when misoprostol is given 48 h later (ctri.nic.in CTRI/2010/091/001422).


Asunto(s)
Abortivos no Esteroideos/administración & dosificación , Abortivos Esteroideos/administración & dosificación , Aborto Inducido/métodos , Mifepristona/administración & dosificación , Misoprostol/administración & dosificación , Adulto , Esquema de Medicación , Femenino , Humanos , Embarazo , Adulto Joven
20.
Chemphyschem ; 17(19): 3120-3128, 2016 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-27442265

RESUMEN

The biomimetic CO2 hydration activity of Ru/Rh-doped fullerenes was revealed by using density functional theory calculations. The mechanism of CO2 hydration on the proposed heterofullerenes followed the mechanistic action of α-carbonic anhydrases, and consisted of the adsorption and deprotonation of H2 O, CO2 interaction with hydroxyl groups, CO2 bending, and proton transfer to give the HCO-3 product. Free-energy landscapes for the reaction showed the catalysts to be active for the reaction. H2 O adsorption over the catalysts was exergonic whereas CO2 adsorption over the catalyst-OH complex was observed to be an endergonic process. Intramolecular proton transfer resulting in the final product, HCO-3 , was found to be the rate-limiting step for the reaction on C56 N3 M (M=Ru/Rh), whereas H2 O dissociation was found to be the rate-limiting step for the reaction on C59 M (M=Ru/Rh). C56 N3 M catalysts were found to be superior to C59 M catalysts for biomimetic CO2 hydration, as indicated by the free-energy landscapes and energy requirements.


Asunto(s)
Materiales Biomiméticos/química , Dióxido de Carbono/química , Anhidrasas Carbónicas/química , Fulerenos/química , Teoría Cuántica , Biocatálisis , Materiales Biomiméticos/metabolismo , Dióxido de Carbono/metabolismo , Anhidrasas Carbónicas/metabolismo , Fulerenos/metabolismo , Rodio/química , Rodio/metabolismo , Rutenio/química , Rutenio/metabolismo , Agua/química , Agua/metabolismo
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