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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   
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Background:

To evaluate and compare the ultrasound (US) features of transient small bowel intussusception (SBI) with those which required surgical management.

Materials and Methods:

US features of 26 children with 32 intussusceptions from January 2014 to August 2014 were recorded and compared with follow-up imaging or surgical findings.

Results:

Transient SBI when compared to surgically managed intussusception has shorter length of intussusception (mean 2.25 cm, range 1.8-4.5 cm vs. mean 5.6 cm, range, 2.3-7.8 cm), smaller transverse diameter (mean, 1.2 cm, range 0.8-2.3 cm vs. mean, 3.3 cm, range 2.9-5.4 cm) and thin wall (mean, 3.3 mm, 2.3-4.9 mm vs. mean, 6.8 mm, range, 4.3-11.2 mm). Four out of five surgically managed intussusceptions were associated with the lead point while none of the transient SBI had any lead point. Peristalsis was absent in all surgically managed intussusceptions.

Conclusion:

Transient SBI is associated with a shorter length of intussusception, smaller transverse diameter, thin walls, absence of the lead point and visible peristalsis. All these findings may help in distinguishing it from those requiring surgical management.Key words: Children, surgically managed small bowel intussusception, transient small bowel intussusception, ultrasound  相似文献   
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Automated blood counts revealing lymphocytosis necessitate smear reviews. Even expert morphological evaluation may however, fail to differentiate a benign-versus-malignant etiology without further testing. Automated analyser-derived quantitative data on leukocyte cell populations remain undertested for distinguishing such etiologies. Instrument manufacturers claim that if successful, they may be used to generate software flags that help under-resourced laboratories better triage hemogram specimens requiring further testing. We tested the diagnostic accuracy of volume-conductivity-scatter (VCS) indices together with complete blood count (CBC) parameters in such scenarios. We compared LH780-derived (Beckman Coulter, FL, USA) CBC + VCS parameters from patients with clonal lymphoproliferations (n = 42, including 30 chronic lymphocytic leukemia cases) versus 83 controls with absolute or relative lymphocytosis (derivation cohort). Diagnostic performances of 11 logistic regression equations derived were subsequently evaluated on two specific validation cohorts (n = 130 and n = 1465). Clonal lymphocytoses showed significantly lower hemoglobin and higher leukocyte counts but similar lymphocyte percentages (LY %) vis-à-vis controls. The most significant, albeit overlapping predictor of clonality was the absolute lymphocyte count, LY# (47.8 ± 48.4 × 109/L vs. 2.9 ± 1.4 × 109/L in clonal vs. benign cases). In eleven logistic regression equations constructed using four combinatorial approaches, only the models with LY# (highest sensitivity/specificity of 99.3%/100%) and the lymphocytic VCS parameters alone (highest sensitivity/specificity of 76.2%/90.2%) performed consistently in both validation cohorts. Lymphocytic VCS parameters were moderately successful in distinguishing benign-versus-malignant lymphocytes. Other approaches of CBC-plus-VCS parameters did not sustain their initial excellent performances in the validation cohorts, highlighting a need for careful appraisal and better standardization of automated cellular analysis technologies.  相似文献   
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Shigella species cause severe bacillary dysentery in humans and are associated with high morbidity and mortality. The Invasion plasmid antigen (IpaB) protein, which is conserved across all Shigella spp., induces macrophage cell death and is required to invade host cells. The present study evaluates the immunogenicity and protective efficacy of the recombinant (r) domain region of IpaB (rIpaB) of S. flexneri. rIpaB was administered either alone or was co-administered with the rGroEL (heat shock protein 60) protein from S. Typhi as an adjuvant in a mouse model of intranasal immunization. The IpaB domain region (37 kDa) of S. flexneri was amplified from an invasion plasmid, cloned, expressed in BL21 Escherichia coli cells and purified. Immunization with the rIpaB domain alone stimulated both humoral and cell-mediated immune responses. Furthermore, robust antibody (IgG, IgA) and T-cell responses were induced when the rIpaB domain was co-administered with rGroEL. Antibody isotyping revealed higher IgG1 and IgG2a antibody titers and increased interferon-gamma (IFN-γ) secretion in the co-administered group. Immunization of mice with the rIpaB domain alone protected 60%–70% of the mice from lethal infection by S. flexneri, S. boydii and S. sonnei, whereas co-administration with rGroEL increased the protective efficacy to 80%–85%. Organ burden and histopathological studies also revealed a significant reduction in lung infection in the co-immunized mice compared with mice immunized with the rIpaB domain alone. This study emphasizes that the co-administration of the rIpaB domain and rGroEL protein improves immune responses in mice and increases protective efficacy against Shigella infection. This is also the first report to evaluate the potential of the GroEL (Hsp 60) protein of S. Typhi as an adjuvant molecule, thereby overcoming the need for commercial adjuvants.  相似文献   
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