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21.
SARS-CoV-2 (CoV2) antibody therapies, including COVID-19 convalescent plasma (CCP), monoclonal antibodies, and hyperimmune globulin, are among the leading treatments for individuals with early COVID-19 infection. The functionality of convalescent plasma varies greatly, but the association of antibody epitope specificities with plasma functionality remains uncharacterized. We assessed antibody functionality and reactivities to peptides across the CoV2 and the 4 endemic human coronavirus (HCoV) genomes in 126 CCP donations. We found strong correlation between plasma functionality and polyclonal antibody targeting of CoV2 spike protein peptides. Antibody reactivity to many HCoV spike peptides also displayed strong correlation with plasma functionality, including pan-coronavirus cross-reactive epitopes located in a conserved region of the fusion peptide. After accounting for antibody cross-reactivity, we identified an association between greater alphacoronavirus NL63 antibody responses and development of highly neutralizing antibodies against CoV2. We also found that plasma preferentially reactive to the CoV2 spike receptor binding domain (RBD), versus the betacoronavirus HKU1 RBD, had higher neutralizing titer. Finally, we developed a 2-peptide serosignature that identifies plasma donations with high anti-spike titer, but that suffer from low neutralizing activity. These results suggest that analysis of coronavirus antibody fine specificities may be useful for selecting desired therapeutics and understanding the complex immune responses elicited by CoV2 infection.  相似文献   
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BACKGROUND Zinc is an essential trace element integral to many cellular and immune functions. Zinc deficiency is highly prevalent in patients with cirrhosis and related to disease severity.AIM To evaluate whether zinc supplementation improves clinical outcomes(disease severity and mortality) in patients with cirrhosis.METHODS This prospectively registered systematic review(PROSPERO reference: CRD42018118219) included all studies in Medline, Embase or Cochrane database with inclusion criteria of adult human studies, comparing zinc supplementation of at least 28 d with standard care or placebo in patients with cirrhosis. Mortality and clinical severity score data were extracted. Random effects meta-analyses compared mortality at 6 mo and 2 years. Risk of bias was assessed using the National Institutes of Health quality assessment tool.RESULTS Seven hundred and twelve articles were identified of which four were eligible. Zinc formulations and doses varied(elemental zinc 3.4-214 mg daily) for different intervention periods in patients with differing etiology and severity of cirrhosis. Two studies were considered to be at high risk of bias. There was no significant difference in 6-mo mortality between patients treated with zinc versus controls [risk ratio 0.98(0.90-1.05)]. Changes in severity scores were not reported in any study.CONCLUSION Zinc supplementation is not associated with reduced mortality in patients with cirrhosis. Findings are limited by the small number of eligible studies and significant heterogeneity in intervention and patient population.  相似文献   
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Background  

Patients with chronic hepatitis C virus (HCV) infection have high rates of alcohol consumption, which is associated with progression of fibrosis and lower response rates to HCV treatment.  相似文献   
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Introduction  

A significant proportion of patients with Crohn’s disease (CD) lose response to antibodies directed against tumor necrosis factor α (TNF). Prior TNF-antagonist failure is associated with lower rates of response to subsequent TNF-antagonist therapy. In patients failing two anti-TNF agents, a choice exists between using a third-anti-TNF therapy or natalizumab (NAT), an α-4 integrin inhibitor. A cost-effectiveness analysis comparing these competing strategies has not been performed.  相似文献   
29.

Aim

We describe the first living donor intestinal transplant (LDIT) in India and discuss the indications and problems of this complex procedure.

Methods

A 43-year-old male patient required massive bowel resection for gangrene due to thrombosis of the superior mesenteric artery. He was maintained on parenteral nutrition but developed cholestasis and well as repeated catheter related infections with progressive loss of venous access due to thrombosis of central veins. A LDIT was performed using 200?cm of small intestine from the patient's son. The graft was based on the continuation of the superior mesenteric vessels beyond the ileocolic branch. The artery was anastomosed directly to the aorta and the vein to the venacava.

Results

The graft functioned well and he was weaned off parenteral nutrition. However, he later developed complications (wound dehiscence and enterocutaneous fistula) and developed sepsis. He succumbed to sepsis with a functioning graft 6?weeks after the transplant. The donor recovered uneventfully and was discharged on the 4th postoperative day.

Conclusions

LDIT can be life saving in patients with intestinal failure and failure of parenteral nutrition. There is a need to introduce this modality in India. In a setting of scarcity of deceased donor organs the living donor option has advantages.  相似文献   
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Hu antigen R (HuR) is a central RNA-binding protein regulating cell dedifferentiation, proliferation, and survival, which are well-established hallmarks of cancer. HuR is frequently overexpressed in tumors correlating with tumor malignancy, which is in line with a role for HuR in tumorigenesis. However, the precise mechanism leading to changes in HuR expression remains unclear. In the liver, HuR plays a crucial role in hepatocyte proliferation, differentiation, and transformation. Here, we unraveled a novel mean of regulation of HuR expression in hepatocellular carcinoma (HCC) and colon cancer. HuR levels correlate with the abundance of the oncogene, murine double minute 2 (Mdm2), in human HCC and colon cancer metastases. HuR is stabilized by Mdm2-mediated NEDDylation in at least three lysine residues, ensuring its nuclear localization and protection from degradation. Conclusion: This novel Mdm2/NEDD8/HuR regulatory framework is essential for the malignant transformation of tumor cells, which, in turn, unveils a novel signaling paradigm that is pharmacologically amenable for cancer therapy.  相似文献   
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