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11.
The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) facilitates viral entry into host cells and is the key target for neutralizing antibodies. The SARS-CoV-2 lineage B.1.620 carries fifteen mutations in the S protein and is spread in Africa, the US and Europe, while lineage R.1 harbors four mutations in S and infections were observed in several countries, particularly Japan and the US. However, the impact of the mutations in B.1.620 and R.1 S proteins on antibody-mediated neutralization and host cell entry are largely unknown. Here, we report that these mutations are compatible with robust ACE2 binding and entry into cell lines, and they markedly reduce neutralization by vaccine-induced antibodies. Our results reveal evasion of neutralizing antibodies by B.1.620 and R.1, which might have contributed to the spread of these lineages.  相似文献   
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Although clinically distinguishable, migraine and cluster headache share prominent features such as unilateral pain, common pharmacological triggers such glyceryl trinitrate, histamine, calcitonin gene-related peptide (CGRP) and response to triptans and neuromodulation. Recent data also suggest efficacy of anti CGRP monoclonal antibodies in both migraine and cluster headache. While exact mechanisms behind both disorders remain to be fully understood, the trigeminovascular system represents one possible common pathophysiological pathway and network of both disorders. Here, we review past and current literature shedding light on similarities and differences in phenotype, heritability, pathophysiology, imaging findings and treatment options of migraine and cluster headache. A continued focus on their shared pathophysiological pathways may be important in paving future treatment avenues that could benefit both migraine and cluster headache patients.  相似文献   
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Purpose of Review

Left ventricular assist device (LVAD) therapy serves as mainstay therapy for bridge to transplantation and destination therapy. Evidence is now mounting on the role of LVAD therapy as bridge to recovery. In the current review, we will summarize the data on biomarkers of myocardial recovery following LVAD implantation.

Recent Findings

Myocardial recovery can occur spontaneously, following pharmacological intervention and in the setting of mechanical circulatory support such as LVAD. Several biomarkers such as B-type natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), ST2, etc. have been identified and are being used to guide medical therapy in heart failure (HF) patients. However, recent data raised concern that those biomarkers may not be helpful in managing heart failure patients in general, and as such questioned their use in the advanced heart failure population. At this point, the use of biomarker to identify patients with myocardial recovery during LVAD support has not been established, and LVAD explantation remains a decision driven by echocardiographic and hemodynamics improvement.

Summary

HF biomarkers in monitoring myocardial and neurohormonal activation response to mechanical unloading and medical therapy could be valuable. However, at this time, there is inadequate evidence to select a single or a set of HF biomarkers to reliably identify patients bridged to recovery for LVAD explantation.
  相似文献   
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Background Campylobacter is one of the most frequent causes of bacterial gastroenteritis. Campylobacter outbreaks are rarely reported, which could be a reflection of a surveillance without routine molecular typing. We have previously shown that numerous small outbreak-like clusters can be detected when whole genome sequencing (WGS) data of clinical Campylobacter isolates was applied.AimTyping-based surveillance of Campylobacter infections was initiated in 2019 to enable detection of large clusters of clinical isolates and to match them to concurrent retail chicken isolates in order to react on ongoing outbreaks.MethodsWe performed WGS continuously on isolates from cases (n = 701) and chicken meat (n = 164) throughout 2019. Core genome multilocus sequence typing was used to detect clusters of clinical isolates and match them to isolates from chicken meat.ResultsSeventy-two clusters were detected, 58 small clusters (2–4 cases) and 14 large clusters (5–91 cases). One third of the clinical isolates matched isolates from chicken meat. One large cluster persisted throughout the whole year and represented 12% of all studied Campylobacter cases. This cluster type was detected in several chicken samples and was traced back to one slaughterhouse, where interventions were implemented to control the outbreak.ConclusionOur WGS-based surveillance has contributed to an improved understanding of the dynamics of the occurrence of Campylobacter strains in chicken meat and the correlation to clusters of human cases.  相似文献   
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Results of a first-stage Sea Urchin Genome Project are summarized here. The species chosen was Strongylocentrotus purpuratus, a research model of major importance in developmental and molecular biology. A virtual map of the genome was constructed by sequencing the ends of 76,020 bacterial artificial chromosome (BAC) recombinants (average length, 125 kb). The BAC-end sequence tag connectors (STCs) occur an average of 10 kb apart, and, together with restriction digest patterns recorded for the same BAC clones, they provide immediate access to contigs of several hundred kilobases surrounding any gene of interest. The STCs survey >5% of the genome and provide the estimate that this genome contains approximately 27,350 protein-coding genes. The frequency distribution and canonical sequences of all middle and highly repetitive sequence families in the genome were obtained from the STCs as well. The 500-kb Hox gene complex of this species is being sequenced in its entirety. In addition, arrayed cDNA libraries of >10(5) clones each were constructed from every major stage of embryogenesis, several individual cell types, and adult tissues and are available to the community. The accumulated STC data and an expanding expressed sequence tag database (at present including >12, 000 sequences) have been reported to GenBank and are accessible on public web sites.  相似文献   
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Inflammatory bowel disease(IBD),which comprises ulcerative colitis and Crohn’s disease,is characterized by inflammation of the gastrointestinal tract.The trefoil factors 1,2,and 3(TFF1-3)are a family of peptides that play important roles in the protection and repair of epithelial surfaces,including the gastrointestinal tract.TFFs may be involved in IBD pathogenesis and are a potential treatment option.In the present review,we describe the TFF family and their potential role in IBD by summarizing the current knowledge of their expression,possible function and pharmacological role in IBD.  相似文献   
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