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41.
BACKGROUNDEvidence supporting convalescent plasma (CP), one of the first investigational treatments for coronavirus disease 2019 (COVID-19), has been inconclusive, leading to conflicting recommendations. The primary objective was to perform a comparative effectiveness study of CP for all-cause, in-hospital mortality in patients with COVID-19.METHODSThe multicenter, electronic health records–based, retrospective study included 44,770 patients hospitalized with COVID-19 in one of 176 HCA Healthcare–affiliated community hospitals. Coarsened exact matching (1:k) was employed, resulting in a sample of 3774 CP and 10,687 comparison patients.RESULTSExamination of mortality using a shared frailty model, controlling for concomitant medications, date of admission, and days from admission to transfusion, demonstrated a significant association of CP with lower mortality risk relative to the comparison group (adjusted hazard ratio [aHR] = 0.71; 95% CI, 0.59–0.86; P < 0.001). Examination of patient risk trajectories, represented by 400 clinico-demographic features from our real-time risk model (RTRM), indicated that patients who received CP recovered more quickly. The stratification of days to transfusion revealed that CP within 3 days after admission, but not within 4 to 7 days, was associated with a significantly lower mortality risk (aHR = 0.53; 95% CI, 0.47–0.60; P < 0.001). CP serology level was inversely associated with mortality when controlling for its interaction with days to transfusion (HR = 0.998; 95% CI, 0.997–0.999; P = 0.013), yet it did not reach univariable significance.CONCLUSIONSThis large, diverse, multicenter cohort study demonstrated that CP, compared with matched controls, is significantly associated with reduced risk of in-hospital mortality. These observations highlight the utility of real-world evidence and suggest the need for further evaluation prior to abandoning CP as a viable therapy for COVID-19.FUNDINGThis research was supported in whole by HCA Healthcare and/or an HCA Healthcare–affiliated entity, including Sarah Cannon and Genospace.  相似文献   
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Hepatitis C virus(HCV)infection is considered a systemic disease because of involvement of other organs and tissues concomitantly with liver disease.Among the extrahepatic manifestations,neuropsychiatric disorders have been reported in up to 50%of chronic HCV infected patients.Both the central and peripheral nervous system may be involved with a wide variety of clinical manifestations.Main HCV-associated neurological conditions include cerebrovascular events,encephalopathy,myelitis,encephalomyelitis,and cognitive impairment,whereas“brain fog”,depression,anxiety,and fatigue are at the top of the list of psychiatric disorders.Moreover,HCV infection is known to cause both motor and sensory peripheral neuropathy in the context of mixed cryoglobulinemia,and has also been recently recognized as an independent risk factor for stroke.These extrahepatic manifestations are independent of severity of the underlying chronic liver disease and hepatic encephalopathy.The brain is a suitable site for HCV replication,where the virus may directly exert neurotoxicity;other mechanisms proposed to explain the pathogenesis of neuropsychiatric disorders in chronic HCV infection include derangement of metabolic pathways of infected cells,alterations in neurotransmitter circuits,autoimmune disorders,and cerebral or systemic inflammation.A pathogenic role for HCV is also suggested by improvement of neurological and psychiatric symptoms in patients achieving a sustained virologic response following interferon treatment;however,further ad hoc trials are needed to fully assess the impact of HCV infection and specific antiviral treatments on associated neuropsychiatric disorders.  相似文献   
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Objective: To evaluate the efficacy of botulinum neurotoxin type A (BoNT/A) for severe oro‐pharyngeal dysphagia associated with multiple sclerosis (MS). Patients and methods: BoNT/A was injected percutaneously into the hyperactive cricopharyngeal muscle of 14 dysphagic MS patients under electromyographic control. Patients were evaluated by videofluoroscopic and electromyographic examinations and by the Penetration/Aspiration Scale (PAS), at week 1, 4, 12, 16, 18, and 24 after BoNT/A injection. Results: All patients showed a significant improvement in all the swallowing outcome measures. Conclusion: No specific treatment for oro‐pharyngeal dysphagia related to MS has been described to date. Our preliminary findings suggest a potential benefit from BoNT/A treatment in MS patients with dysphagia associated with upper esophageal sphincter hyperactivity.  相似文献   
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Objective  

To identify which equation, Siri or Brozek, based on the two compartment model, provides a more accurate conversion of body density (BD) in percent body fat (%BF) in a group of older adults.  相似文献   
46.
BACKGROUND: Iron deficiency (ID) is the main cause of hyporesponsiveness to erythropoietin in haemodialysis patients and its detection is of value since it is easily corrected by intravenous iron. Markers of iron supply to the erythron, including erythrocyte zinc protoporphyrin (Er-ZPP), percentage of hypochromic erythrocytes (Hypo), reticulocyte haemoglobin content (CHr) and soluble transferrin receptor (sTfR), may be more accurate predictors of ID than ferritin (Fer) and transferrin saturation (TSat), but relative diagnostic power and best threshold values are not yet established. METHODS: In 125 haemodialysis patients on maintenance erythropoietin, the diagnostic power of the above parameters was evaluated by ROC curve, multivariate regression, and stepwise discriminant analyses. Diagnosis of ID was based on haemoglobin response to intravenous iron (992 mg as sodium ferric gluconate complex over an 8-week period). RESULTS: Fifty-one patients were considered iron deficient (haemoglobin increase by 1.9+/-0.5 g/dl) and 74 as iron replete (haemoglobin increase by 0.4+/-0.3 g/dl). ROC curve analysis showed that all tests had discriminative ability with the following hierarchy: Hypo (area under curve W=0.930, efficiency 89.6% at cut-off >6%), CHr (W=0.798, efficiency 78.4% at cut-off < or =29 pg), sTfR (W=0.783, efficiency 72.4% at cut-off >1.5 mg/l), Er-ZPP (W=0.773, efficiency 73.0% at cut-off >52 micromol/mol haem), TSat (W=0.758, efficiency 70.4% at cut-off <19%) and ferritin (W=0.633, efficiency 64.0% at cut-off <50 ng/ml). Stepwise discriminant analysis identified Hypo as the only variable with independent diagnostic value, able to classify 87.2% of patients correctly. Additional tests did not substantially improve diagnostic efficiency of Hypo >6% alone. CONCLUSIONS: In haemodialysis patients on maintenance erythropoietin, Hypo >6% is the best currently available marker to identify those who will improve their response after intravenous iron. Cost-effectiveness suggests that this parameter should be a first-line tool to monitor iron requirements in clinical practice.  相似文献   
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Background

Complete pathologic response (CPR) after neoadjuvant chemoradiotherapy (combined modality treatment, CMT) for rectal cancer seems associated with improved survival compared to partial or no response (NPR). However, previous reports have been limited by small sample size and single-institution design.

Methods

A systematic literature review was conducted to detect studies comparing long-term results of patients with CPR and NPR after CMT for rectal cancer. Variables were pooled only if evaluated by 3 or more studies. Study end points included rates of CPR, local recurrence (LR), distant recurrence (DR), 5-year overall survival (OS), and disease-free survival (DFS).

Results

Twelve studies (1,913 patients) with rectal cancer treated with CMT were included. CPR was observed in 300 patients (15.6%). CPR and NPR patient groups were similar with respect to age, sex, tumor size, distance of tumor from the anus, and stage of disease before treatment. Median follow-up ranged from 23 to 46?months. CPR patients had lower rates of LR [0.7% vs. 2.6%; odds ratio (OR) 0.45, 95% confidence interval (CI) 0.22?C0.90, P?=?0.03], DR (5.3% vs. 24.1%; OR 0.15, 95% CI 0.07?C0.31, P?=?0.0001), and simultaneous LR?+?DR (0.7% vs. 4.8%; OR 0.32, 95% CI 0.13?C0.79, P?=?0.01). OS was 92.9% for CPR versus 73.4% for NPR (OR 3.6, 95% CI 1.84?C7.22, P?=?0.002), and DFS was 86.9% versus 63.9% (OR 3.53, 95% CI 1.62?C7.72, P?=?0.002).

Conclusions

CPR after CMT for rectal cancer is associated with improved local and distal control as well as better OS and DFS.  相似文献   
49.
Summary Nicotiana plumbaginifolia protoplasts grown at 25 °C and transferred at 40 °C synthesized new temperature-dependent polypeptides called heat-shock proteins (hsp) distributed in a wide range of molecular weight. The cellular localization of hsp showed a concentration of the low molecular weight hsp in a fraction enriched in membranes and chloroplasts. Purified chloroplasts obtained by a Percoll cushion and by a discontinuous sucrose density gradient centrifugation, were therefore analyzed for hsp distribution. Several hsp were found to be associated with this subcellular compartment: in particular three hsp were associated with the soluble fraction of the chloroplasts, whereas six hsp were associated with organelle membranes. The involvment of chloroplast information in the synthesis of some of these organelle associated hsp and therefore in the response to heat-shock is discussed.This work was supported by C.N.R., Italy — Special grant IPRA Subproject 1  相似文献   
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