Japanese encephalitis virus (JEV) is the leading global cause of viral encephalitis. The JEV envelope protein (E) facilitates cellular attachment and membrane fusion and is the primary target of neutralizing antibodies. We have determined the 2.1-Å resolution crystal structure of the JEV E ectodomain refolded from bacterial inclusion bodies. The E protein possesses the three domains characteristic of flavivirus envelopes and epitope mapping of neutralizing antibodies onto the structure reveals determinants that correspond to the domain I lateral ridge, fusion loop, domain III lateral ridge, and domain I-II hinge. While monomeric in solution, JEV E assembles as an antiparallel dimer in the crystal lattice organized in a highly similar fashion as seen in cryoelectron microscopy models of mature flavivirus virions. The dimer interface, however, is remarkably small and lacks many of the domain II contacts observed in other flavivirus E homodimers. In addition, uniquely conserved histidines within the JEV serocomplex suggest that pH-mediated structural transitions may be aided by lateral interactions outside the dimer interface in the icosahedral virion. Our results suggest that variation in dimer structure and stability may significantly influence the assembly, receptor interaction, and uncoating of virions.

Background Peroral endoscopic myotomy (POEM) is considered a primary treatment modality for achalasia. It can be performed using either the anterior or posterior approach. A previous randomized clinical trial (RCT) showed that the posterior approach was noninferior to the anterior approach at 1 year post-POEM in terms of clinical success, rate of adverse event, and risk of gastroesophageal reflux disease (GERD). The aim of this post-RCT study was to compare outcomes at ≥ 2 years post-POEM. Methods Patients who previously completed the 1-year follow-up were contacted and their Eckardt, dysphagia, and GERD questionnaire (GERDQ) scores and frequency of proton pump inhibitor use were recorded. Clinical success was defined as an Eckardt score < 3. Results 150 patients were initially randomized and 138 completed the 1-year follow-up. Of the 138, 111 (anterior group 54, posterior group 57) also completed ≥ 2 years of follow-up, with an overall clinical success decrease from 89 % to 82 %. At ≥ 2 years post-POEM, clinical success was achieved in 46/54 (85 %) and 45/57 (79 %) in the anterior and posterior groups, respectively (P = 0.43). A similar decrease in clinical success was noted in both groups at ≥ 2 years (anterior: 90 % to 85 %; posterior 89 % to 79 %; P = 0.47). GERDQ score was 6 (interquartile range 6 – 8; P = 0.08) in both treatment groups. Conclusions The anterior and posterior POEM techniques remained equally effective at 2 years and decreases in efficacy were similar between the two approaches over time. GERD outcomes were also similar in both groups during medium-term follow-up.

Background and study aims The aim of this study was to assess long-term clinical outcomes beyond 6 years in patients who underwent per-oral endoscopic myotomy (POEM) for the treatment of achalasia. Patients and methods Patients with achalasia who underwent POEM between 2010 and 2012 and had follow-up of at least 6 years were retrospectively identified at eight tertiary care centers. The primary outcome evaluated was clinical success defined by an Eckardt symptom score (ESS) ≤ 3 for the duration of the follow-up period. The clinical success cohort was compared to failure (ESS > 3 at any time during follow-up) in order to identify characteristics associated with symptom relapse. The incidence of patient-reported gastroesophageal reflux (GER) was also evaluated. Results Seventy-three patients with 6-year follow-up data were identified. Sustained clinical remission was noted in 89 % (65/73) at 6-years. Mean ESS decreased from 7.1 ± 2.3 pre-procedure to 1.1 ± 1.1 at 6 years (P < 0.001). Symptomatic reflux was reported by 27 of 72 patients (37.5 %). Type I achalasia (OR 10.8, P = 0.04) was found to be associated with clinical failure on logistic regression analysis. Conclusions In patients with achalasia, POEM provides high initial clinical success with excellent long-term outcomes. There are high rates of patient-reported gastroesophageal reflux post-procedure which persist at long-term follow-up.

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Here we used patterned self-assembled monolayer (SAM) chemistry to explore the role of spatial confinement on the growth and proliferation of a developing neuron. Despite extensive previous work on the molecular mechanisms controlling these processes, classical biological approaches have not been able to clearly distinguish whether differentiation is predetermined or environmentally determined.

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