HIV-1 requires capsid remodelling at the nuclear pore for nuclear entry and integration.

The capsid (CA) lattice of the HIV-1 core plays a key role during infection. From the moment the core is released into the cytoplasm, it interacts with a range of cellular factors that, ultimately, direct the pre-integration complex to the integration site. For integration to occur, the CA lattice must disassemble. Early uncoating or a failure to do so has detrimental effects on virus infectivity, indicating that an optimal stability of the viral core is crucial for infection. Here, we introduced cysteine residues into HIV-1 CA in order to induce disulphide bond formation and engineer hyper-stable mutants that are slower or unable to uncoat, and then followed their replication. From a panel of mutants, we identified three with increased capsid stability in cells and found that, whilst the M68C/E212C mutant had a 5-fold reduction in reverse transcription, two mutants, A14C/E45C and E180C, were able to reverse transcribe to approximately WT levels in cycling cells. Moreover, these mutants only had a 5-fold reduction in 2-LTR circle production, suggesting that not only could reverse transcription complete in hyper-stable cores, but that the nascent viral cDNA could enter the nuclear compartment. Furthermore, we observed A14C/E45C mutant capsid in nuclear and chromatin-associated fractions implying that the hyper-stable cores themselves entered the nucleus. Immunofluorescence studies revealed that although the A14C/E45C mutant capsid reached the nuclear pore with the same kinetics as wild type capsid, it was then retained at the pore in association with Nup153. Crucially, infection with the hyper-stable mutants did not promote CPSF6 re-localisation to nuclear speckles, despite the mutant capsids being competent for CPSF6 binding. These observations suggest that hyper-stable cores are not able to uncoat, or remodel, enough to pass through or dissociate from the nuclear pore and integrate successfully. This, is turn, highlights the importance of capsid lattice flexibility for nuclear entry. In conclusion, we hypothesise that during a productive infection, a capsid remodelling step takes place at the nuclear pore that releases the core complex from Nup153, and relays it to CPSF6, which then localises it to chromatin ready for integration.

Effect of medical school attended on the chances of successfully embarking on a clinical-academic career in the UK.

PURPOSE OF THE STUDY: This study aimed to investigate whether, in the UK, medical school attended influences the propensity to apply to and be successful in obtaining an offer from the Academic Foundation Programme (AFP), thus taking the first step to embarking on a clinical-academic career. STUDY DESIGN: A retrospective observational study was performed. Using the UK Foundation Programme's yearly statistical report data, mean application rates to, and mean offer rates from the AFP were calculated by medical school, between the years 2017-2019. Mean application and mean offer rates were subsequently correlated with metrics of medical school academic performance and research focus. RESULTS: Mean application rates to the AFP were higher in medical schools that had a mandatory intercalated degree as part of the undergraduate medical curriculum (mean=33.99%, SD=13.93 vs mean=19.44%, SD=6.88, p<0.001), lower numerical rank in the Times Higher Education 2019 World Rankings (correlation with higher numerical rank, r=-0.50, p=0.004), and lower numerical rank in the Research Excellence Framework 2014 UK rankings (correlation with higher numerical rank, r=-0.37, p=0.004). Mean offer rates from the AFP were not correlated with any metric of medical school academic performance or research focus. CONCLUSIONS: Students attending a medical school with greater academic performance and research focus are more likely to apply and subsequently embark on a clinical-academic career. However, students wishing to embark a clinical-academic career from any medical school have an equal chance of success.

The salient role of microRNAs in atherogenesis.

Atherosclerosis, a chronic inflammatory condition that is characterized by the accumulation of lipid-loaded macrophages, occurs preferentially at the arterial branching points where disturbed flow is prominent. The pathogenesis of atherosclerotic lesion formation is a multistage process involving multiple cell types, inflammatory mediators and hemodynamic forces in the vessel wall in response to atherogenic stimuli. Researches from the past decade have uncovered the critical roles of microRNAs (miRNAs) in regulating multiple pathophysiological effects and signaling pathways in endothelial cells (ECs), vascular smooth muscle cells (VSMCs), macrophages and lipid homeostasis, which are key in atherosclerotic lesion formation. The expression of these miRNAs are either in response to biomechanical (flow-responsive) or biochemical (non-flow-responsive) stimuli. Recent evidences also indicate an important role for long non-coding RNAs (lncRNAs) in mediating several atherosclerotic processes. In this review, we provide a detailed summary on the current paradigms in miRNA-dependent regulation, the emerging role of lncRNAs in the initiation and progression of atherosclerosis, and clinical interventions targeting these in an attempt to develop novel diagnostics and treatments for atherosclerosis.

Use of DECAF scoring system to facilitate early discharge in acute exacerbation of COPD patients: a quality improvement project at a district general hospital.

INTRODUCTION: DECAF is a scoring tool that can predict severity in patients with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Previous research has shown AECOPD patients with DECAF scores of 0-1 are candidates for early discharge. METHODS: Plan, do, study, act (PDSA) methodology was used. Patients with AECOPD and a DECAF score of 0-1 were included. Notes were retrospectively reviewed for patients for DECAF score, length of stay, 30-day re-admission and 30-day mortality (PDSA cycle 1). A framework to facilitate early discharge for patients was subsequently established. Awareness was increased through teaching sessions, posters and targeted emails. To evaluate our improvements, the same parameters were collected prospectively (PDSA cycle 2). RESULTS: DECAF score was assessed for no patients in PDSA cycle 1 (n=20) but was assessed for all patients in PDSA cycle 2 (n=14). Hospital stay was significantly decreased in PDSA cycle 2 (mean 0.29±0.45 days) compared with PDSA cycle 1 (mean 3.71±2.69 days; difference p<0.00001). Thirty-day re-admission and 30-day mortality was not significantly different between two groups. CONCLUSION: DECAF protocol is safe and feasible in the district general hospital setting and can facilitate early discharge for patients with low severity AECOPD without any worrisome effects.

Admission ultrasonography as a predictive tool for thrombocytopenia and disease severity in dengue infection.

BACKGROUND: Ultrasound (US) is an investigation available in many acute care settings. Thrombocytopenia is a well-described complication of dengue infection and has been shown to correlate with disease severity. The purpose of this study was to assess the utility of admission ultrasonography in predicting thrombocytopenia and disease severity in patients infected with dengue virus. METHODS: Data were collected prospectively on 176 patients (male, n=86; female, n=90) admitted to the Nawaloka Hospital, Sri Lanka with dengue infection between December 2016 and August 2018. All patients had an US scan on admission and disease severity was determined using the World Health Organization 2009 classification. RESULTS: There were 106 (60.2%) cases of dengue with/without warning signs and 70 (39.8%) cases of severe dengue. Patients with an abnormal US on admission were more likely to have severe dengue. Gallbladder wall thickening was the most common US abnormality. Abnormal US findings significantly correlated with more pronounced thrombocytopenia from day 2 of admission. CONCLUSIONS: An abnormal US scan on admission can aid in identification of patients at risk of developing severe dengue and can be used as a novel clinical tool to identify patients at risk of severe thrombocytopenia.

"As Black as Ink": A Case of Alkaptonuria-Associated Myelopathy and a Review of the Literature.

STUDY DESIGN: Case report and literature review. OBJECTIVE: To characterize the rare presentation of myelopathy occurring secondary to alkaptonuria and to evaluate the available evidence regarding its treatment. SUMMARY OF BACKGROUND DATA: Alkaptonuria is an autosomal recessive genetic condition with an estimated incidence of 1 in 250,000 to 1 in 1,000,000 people. Mutation of the enzyme homogentisate 1,2-dioxygenase leads to the production of high levels of homogentisic acid, with subsequent deposition in ligaments, cartilage, and menisci. Involvement of the spine is termed "ochronotic spondyloarthropathy," of which myelopathy is an uncommon presentation. METHODS: We present the case of a 57-year-old man with alkaptonuria-associated myelopathy, who underwent surgical decompression. Ten additional cases were identified in the literature by a systematic search of PubMed and Google Scholar. RESULTS: In a patient presenting with myelopathy, alkaptonuria may be suspected because of medical history, family history, symptoms (including darkened urine, pigmented ear cartilage, and sclera), or radiographic changes, such as multilevel disc collapse, progressive wafer-like disc calcification, extensive osteophyte formation, and spinal deformity. The diagnosis can be confirmed by urine homogentisic acid testing. Of the 11 patients presented here or identified in the literature, 2 were treated nonoperatively, 8 were treated with decompressive spinal surgery, and treatment of the myelopathy was not discussed for 1 patient. In all cases in which outcomes were reported, substantial improvement in the patient's condition was seen. CONCLUSION: Alkaptonuria is a rare cause of myelopathy, but one that clinicians should understand. Although no disease-modifying treatment currently exists for alkaptonuria, the use of symptomatic treatments and, particularly, surgical decompression is recommended to address myelopathy if it develops. LEVEL OF EVIDENCE: 4.

Difficulties in Treating Postirradiation Kyphosis in Adults: A Series of Five Cases.

STUDY DESIGN: Clinical case series. OBJECTIVE: To assess objective outcomes of surgical correction of post-external beam radiation therapy (ERBT) kyphosis in a series of five adults. SUMMARY OF BACKGROUND DATA: EBRT is a well-established treatment for many cancers in children and adults. One complication associated with EBRT is postirradiation spine deformity. Scoliosis is the most common deformity, but kyphosis also occurs frequently. Differences in deformity patterns are likely related to the location and intensity of radiation. To our knowledge, no studies have addressed treatment of these deformities in adults, and the most recent case series (of children) was published in 2005. METHODS: We present a series of five adults who underwent surgery for postirradiation kyphosis, with a mean follow-up of 3.8 years (range, 2.5-6.2 years). RESULTS: Surgery improved the kyphotic deformity in all patients. Overall mean kyphotic deformity correction was 56° and was larger for cervical/cervicothoracic deformities (mean, 76°) than for lumbar deformities (mean, 42°) at midterm follow-up. Patients reported significant improvements in pain and self-image. Consistent with prior case series of children, we observed a high rate of complications (mean, 1.4 complications per patient) in adults. Three patients each underwent an unplanned surgical procedure because of a complication. CONCLUSION: The surgical treatment of postirradiation kyphotic spinal deformity is challenging, with common postoperative complications such as infection, instrumentation failure, and pseudarthrosis. However, with modern surgical techniques and spinal instrumentation, excellent deformity correction can be achieved and maintained. We recommend performing a two-stage procedure for cervicothoracic deformity, with anterior release followed by posterior fusion and instrumentation. In thoracolumbar deformities, correction can be achieved through single-stage posterior fusion. Rigid spinopelvic fixation with sacral-alar-iliac screws and second-stage anterior lumbar interbody fusion at L5-S1 is recommended to reduce nonunion risk. Cement augmentation of proximal and distal anchors can help prevent junctional failure. LEVEL OF EVIDENCE: Level IV.

Trends in isolated lumbar spinal stenosis surgery among working US adults aged 40-64 years, 2010-2014.

OBJECTIVE Recommendations for the surgical treatment of isolated lumbar spinal stenosis (LSS) (i.e., in the absence of concomitant scoliosis or spondylolisthesis) are unclear. The aims of this study were to investigate trends in the surgical treatment of isolated LSS in US adults and determine implications for outcomes. METHODS The authors analyzed inpatient and outpatient claims from the Truven Health Analytics MarketScan Commercial Claims and Encounters Database for 20,279 patients aged 40-64 years who underwent surgery for LSS between 2010 and 2014. Only patients with continuous 12-month insurance coverage after surgery were included. The rates of decompression with arthrodesis versus decompression only and of simple (1- or 2-level, single-approach) versus complex (> 2-level or combined-approach) arthrodesis were analyzed by year and geographic region. These trends were further analyzed with respect to complications, length of hospital stay, payments made to the hospital, and patient discharge status. Statistical significance was set at p < 0.05. RESULTS The proportion of patients who underwent decompression with arthrodesis compared with decompression only increased significantly and linearly from 2010 to 2014 (OR 1.08; 95% CI 1.06-1.10). Arthrodesis was more likely to be complex rather than simple with each subsequent year (OR 1.4; 95% CI 1.33-1.49). This trend was accompanied by an increased likelihood of postoperative complications (OR 1.11; 95% CI 1.02-1.21), higher costs (payments increased by a mean of US$1633 per year; 95% CI 1327-1939), and greater likelihood of being discharged to a skilled nursing facility as opposed to home (OR 1.11; 95% CI 1.03-1.20). The South and Midwest regions of the US had the highest proportions of patients undergoing arthrodesis (48% and 42%, respectively). The mean length of hospital stay did not change significantly (p = 0.324). CONCLUSIONS From 2010 to 2014, the proportion of adults undergoing decompression with arthrodesis versus decompression only for the treatment of LSS increased, especially in the South and Midwest regions of the US. A greater proportion of these fusions were complex and were associated with more complications, higher costs, and a greater likelihood of being discharged to a skilled nursing facility.

Delayed primary HHV-7 infection and neurologic disease.

BACKGROUND: Primary human herpesvirus 7 (HHV-7) infection occurs almost universally during the first 5 years of life and is rarely accompanied by central nervous system (CNS) symptoms such as febrile seizures. The present retrospective study investigated the role of primary HHV-7 infection in CNS disease in children, including adolescents. METHODS: The study included all children who had neurologic disease aged younger than 18 years seen at the Hospital for Sick Children, Toronto, Canada, between April 1, 1998 and December 31, 2011, whose cerebrospinal fluid (CSF) was found by polymerase chain reaction to contain HHV-7 DNA. Where sera were available, HHV-7 IgG antibody titers and avidity were measured to differentiate primary from past infection. RESULTS: HHV-7 DNA was detected in the CSF of 57 (1.9%) of the 2972 children tested. In 3 adolescents primary HHV-7 infection (low avidity IgG) was confirmed as the cause of neurologic disease, 2 who had encephalitis and 1 who had Guillain-Barré syndrome. Eighteen children had possible HHV-7 disease (no alternative cause identified and indeterminate antibody result or serum not available), 7 encephalitis, 8 meningitis, and 3 demyelinating disorders. HHV-7 disease was excluded in 36 children on the basis of past infection (high IgG avidity) and/or an alternative cause. CONCLUSIONS: Primary HHV-7 infection delayed into adolescence can cause serious neurologic disease. HHV-7 DNA in CSF alone is insufficient to prove an etiologic association. Combining CSF polymerase chain reaction with serology is essential to prove primary infection when investigating HHV-7 CNS disease.

Genome Sequence of Human Herpesvirus 7 Strain UCL-1.

The sequence of human herpesvirus 7 (HHV-7) strain UCL-1 was determined using target enrichment and next-generation sequencing methods. We have identified 86 putative open reading frames (ORFs), and comparative sequence analyses demonstrate that this strain is closely related to the previously sequenced HHV-7 strains RK and JI.