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971.
972.
Background and aimsPreconditioning using different protocols has been tested to prevent antibody mediated rejection (ABMR) individually for ABO and HLA incompatibility. However, simultaneous presence of both barriers is still less explored. The aim of this study was to report outcomes of institutional desensitization protocol in renal transplant recipients with simultaneous ABO and HLA incompatibility.Materials and methodsThis was a retrospective study conducted from October 2015 to December 2018. All patients with a clinical diagnosis of dialysis dependent chronic kidney disease (CKD), who were prospective coexistent HLA and ABO incompatible renal transplant recipients were included in the study. Patients were followed up and graft function and patient survival was assessed at 1 y from the date of transplant.ResultsMedian and mode baseline anti-A titers were 64, while median and mode baseline anti-B titers were 256. All recipients were discharged by tenth postoperative day. None of the patients had any bleeding complications. Post transplant infection rate was found to be 20 %. A total of 54 therapeutic plasma exchange (TPE) procedures were performed before transplant and 8 were performed after transplant. Graft survival and patient survival was 100 % at 3, 6, 9, and 12 months. Range and mean follow-up period was 15–42 months and 23 months respectively. Mean glomerular filtration rate (GFR) at 1 y using the CKD-EPI equation was 85.25 ± 13.76 mL/min. Biopsy proven ABMR was observed in one case only which was managed with TPE and immunosuppression.ConclusionSimultaneous ABO and HLA incompatibility in renal transplant recipients can be managed successfully with adequate preconditioning and careful monitoring.  相似文献   
973.
974.
IntroductionHydroxychloroquine (HCQ)/Chloroquine (CQ) has been evaluated for treatment and prophylaxis against SARS-CoV-2 infection in various studies with conflicting results. We performed a systematic review to synthesize the currently available evidence over the efficacy and safety of HCQ/CQ therapy alone against SARS-CoV-2 infection.MethodsWe searched Embase, PubMed, Web of Science, and Cochrane central for randomized controlled trials (RCTs) and prospective cohort studies published until October 15, 2020 and assessing the efficacy of HCQ alone against SARS-CoV-2 infection. We included studies evaluating HCQ/CQ alone as intervention and placebo/standard care as a control group. Retrospective studies and studies using other drugs (namely azithromycin, corticosteroids, immunomodulators, etc.) we excluded. Thirteen RCTs and three prospective cohort studies were included in this review. We pooled data using a random-effect model.ResultsPooled data from 12 studies (9917 participants) showed that HCQs increase mortality as compared to placebo/standard of care (RR 1.10; 95% CI:1.00–1.20). Hydroxychloroquine did not reduce the need for hospitalization in out-patients (RR 0.57; 95% CI 0.31–1.02). HCQ group has a significantly higher rate of any adverse event (RR 2.68; 95% CI 1.55–4.64), as compared to the control group. Also, using HCQ for prophylaxis against SARS-CoV-2 infection did not reduce the risk of acquiring SARS-CoV-2 infection (RR 1.04; 95% CI 0.58–1.88).ConclusionsHCQ therapy for COVID-19 is associated with an increase in mortality and other adverse events. The negative effects are more pronounced in hospitalized patients. Therefore, with the available evidence, HCQ should not be used in prophylaxis or treatment of patients with COVID-19.  相似文献   
975.
BackgroundCombined obstetric and neonatal emergency simulation based training is gaining popularity in healthcare settings. Methods: In this qualitative study, through semi-structured one to one interviews, we evaluated participant attitudes, perceptions of retention of learning, and application to clinical practice one year after a simulation workshop. Audio recordings of interviews were transcribed, collated and subjected to thematic analysis. Results: Five major themes were identified through the thematic analysis: comparing simulation to clinical practice; learning and working in teams; thinking retention and sustainability; relating relevance of simulation based education to roles; and managing leadership. Conclusions: Participants’ acknowledgement of training being relevant to their routine practice, and keenness to learn management of complicated births highlighted the sustained impact of obstetric and neonatal emergency simulation training.  相似文献   
976.
977.
This article proposes a method to produce bio-elastomer nanocomposites, based on polyfarnesene or polymyrcene, reinforced with surface-modified graphene oxide (GO). The surface modification is performed by grafting alkylamines (octyl-, dodecyl-, and hexadecylamine) onto the surface of GO. The successful grafting was confirmed via spectroscopic (FTIR and Raman) and X-ray diffraction techniques. The estimated grafted amines appear to be around 30 wt%, as calculated via thermogravimetric analysis, increasing the inter-planar spacing among the nanosheets as a function of alkyl length in the amine. The resulting modified GOs were then used to prepare bio-elastomer nanocomposites via in situ coordination polymerization (using a ternary neodymium-based catalytic system), acting as reinforcing additives of polymyrcene and polyfarnesene. We demonstrated that the presence of the modified GO does not affect significantly the catalytic activity, nor the microstructure-control of the catalyst, which led to high cis-1,4 content bio-elastomers (>95%). Moreover, we show via rheometry that the presence of the modified-GO expands the capacity of the elastomer to store deformation or applied stress, as well as exhibit an activation energy an order of magnitude higher.

This article proposes a method to produce bio-elastomer nanocomposites, based on polyfarnesene or polymyrcene, reinforced with surface-modified graphene oxide (GO).  相似文献   
978.
Dispiroheterocycles have been synthesized by pseudo-four component reaction of 6-aminouracil/6-amino-2-thiouracil/2-amino-1,3,4-thiadiazole, p-toluidine and isatins in an ethanol–water mixture as solvent using β-cyclodextrin functionalized Fe3O4 nanoparticles as a magnetically separable and reusable heterogeneous catalyst. The nanocatalyst was synthesized and characterized by physicochemical characterization including Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD).

An efficient and sustainable synthetic protocol has been presented for the synthesis of dispiroheterocycles using a magnetically separable and reusable nanostructured heterogeneous catalyst.  相似文献   
979.
Correction for ‘Thermodynamically stable vesicle formation of biodegradable double mPEG-tailed amphiphiles with sulfonate head group’ by Rita Ghosh et al., RSC Adv., 2020, 10, 32522–32531, DOI: 10.1039/D0RA05613H

The authors regret that an incorrect version of Fig. 5 was included in the original article. The correct version of Fig. 5 is presented below.Open in a separate windowFig. 1Upper panel: Size distribution histograms of aggregates in 2.0 mM solutions (pH 7) of (a) (mPEG4)2SO3Na, and (b) (mPEG23)2SO3Na at 25 °C; lower panel: unstained HRTEM images of 2 mM (c) (mPEG4)2SO3Na and (d) (mPEG23)2SO3Na solutions in phosphate buffer (pH 7.0).The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
980.
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