HIV-1 uncoating occurs via a series of rapid biomechanical changes in the core related to individual stages of reverse transcription.

The HIV core consists of the viral genome and associated proteins encased by a cone-shaped protein shell termed the capsid. Successful infection requires reverse transcription of the viral genome and disassembly of the capsid shell within a cell in a process known as uncoating. The integrity of the viral capsid is critical for reverse transcription, yet the viral capsid must be breached to release the nascent viral DNA prior to integration. We employed atomic force microscopy to study the stiffness changes in HIV-1 cores during reverse transcription in vitro in reactions containing the capsid-stabilizing host metabolite IP6 Cores exhibited a series of stiffness spikes, with up to three spikes typically occurring between 10-30, 40-80, and 120-160 minutes after initiation of reverse transcription. Addition of the reverse transcriptase (RT) inhibitor efavirenz eliminated the appearance of these spikes and the subsequent disassembly of the capsid, thus establishing that both result from reverse transcription. Using timed addition of efavirenz, and analysis of an RNAseH-defective RT mutant, we established that the first stiffness spike requires minus-strand strong stop DNA synthesis, with subsequent spikes requiring later stages of reverse transcription. Additional rapid AFM imaging experiments revealed repeated morphological changes in cores that were temporally correlated with the observed stiffness spikes. Our study reveals discrete mechanical changes in the viral core that are likely related to specific stages of reverse transcription. These reverse-transcription-induced changes in the capsid progressively remodel the viral core to prime it for temporally accurate uncoating in target cells.ImportanceFor successful infection, the HIV-1 genome, which is enclosed inside a capsid shell, must be reverse transcribed into double-stranded DNA and released from the capsid (in a process known as uncoating) before it can be integrated into the target cell genome. The mechanism of HIV-1 uncoating is a pivotal question of long standing. Using atomic force microscopy to analyze individual HIV-1 cores during reverse transcription, we observe a reproducible pattern of stiffness spikes. These spikes were shown to be associated with distinct stages of the reverse transcription reaction. Our findings suggest that these reverse-transcription-induced alterations gradually prepared the core for uncoating at the right time and location in target cells.

Performance of carbendazim removal using constructed wetlands for the Ethiopian floriculture industry.

Carbendazim is a pesticide commonly used in Ethiopian flower farms and has harmful effects on aquatic, invertebrate, and mammalian life. Previous studies have explored ways to remedy carbendazim toxicity; however, the use of constructed wetland (CW) systems for carbendazim removal from farm water runoff has not been explored in depth. The primary aim of this study was to investigate the efficacy of a CW system for carbendazim removal from wastewater runoff. A two-stage pilot CW was built and tested for its efficacy of carbendazim removal under saturated conditions and varying hydraulic loading rates. The influent was pumped into the first vertical-flow mesocosm. The drained water was then pumped into the second mesocosm. The collected effluent was tested for carbendazim removal. Carbendazim removal efficiencies up to 91.80% (with a hydraulic loading rate of 100 Ld-1 and influent carbendazim concentration of 10 µg L-1) were observed. Statistical analysis indicated that the removal of carbendazim was not correlated with the initial carbendazim concentration but was negatively correlated with the hydraulic loading rate used. Two pesticide removal mechanisms were briefly probed to determine their participation in carbendazim removal. Substrate sorption accounted for 18% of total carbendazim removal; furthermore, plant uptake also played an active role.

Free thyroid transfer to anterolateral thigh for prevention of radiation induced hypothyroidism: An initial experience.

AIM: Radiation induced hypothyroidism (RIHT) is one of the commonest late side effects of radiation therapy and is seen in more than half of patients and affects quality of life significantly. We report our initial experience on feasibility of free microvascular transfer of thyroid gland out of radiation field to prevent development of RIHT. MATERIAL AND METHODS: A prospective pilot study was undertaken during August 2017 to May 2018. Six Patients with stage III/IV patients of oral cavity cancers who required wide excision/composite resections with microvascular free flap (ALT) reconstruction and adjuvant radiation therapy were enrolled. A written informed consent was obtained from all patients prior to the procedure. RESULTS: The mean age of cohort was 51 years with tongue most common site of primary cancer. The free transfer of thyroid gland to anterolateral thigh was done using microvascular technique. The mean additional time for procedure was 51 min. All patients had successful transfer with no associated immediate complications. Patients were followed up with Tc99 scan, USG Doppler and biochemical assay at routine intervals in peri and postoperative period to assess the anatomical and physiological function of the transferred gland. At median follow up of 8 months, 5 patients were euthyroid and remaining one had biochemical hypothyroidism. All patients had functional thyroid gland in anetrolateral thigh. Five patient were alive, one patient died due to disease. CONCLUSION: This is a small and early feasibility study for free thyroid gland transfer and validates the previously published data. The selected group of patients who have high chances of developing RIHT may benefit from this strategy. Further validation of the technique may be explored in a larger cohort.

Free anteromedial thigh perforator flap: Complementing and completing the anterolateral thigh flap.

OBJECTIVE: Theobjective of this study was to determine the indications, utility, advantages and surgical approach for the anteromedial thigh (AMT) flap. MATERIALS AND METHODS: We reviewed the records of the patients in whom the AMT flap was used for head and neck reconstruction. We use an anterior approach to harvest the anterolateral thigh (ALT) flap with a non-committal straight line incision. This preserves both ALT and AMT flap territories intact, and further decision is based on the intraoperative anatomy of perforator and pedicle. The ALT flap was usually used as the first choice when available and suitable. RESULTS: Free AMT skin flaps were harvested in 24 patients. All flaps were used for the head and neck reconstruction. Two flaps had marginal flap necrosis. One flap was lost due to venous thrombosis. DISCUSSION: The thigh is an excellent donor site as it has large available skin territory, expendable lateral circumflex femoral artery system and low donorsite morbidity. The ALT flap is the most commonly used flap for reconstruction of soft-tissue defects. However, it is characterised by variable vascular pedicle and perforator anatomy. The AMT flap is an excellent alternative when the ALT flap is not available due to variable perforator anatomy, injury to perforator, when an intermediate thickness is needed between distal and proximal thigh or a chimeric flap is needed. CONCLUSION: The AMT flap offers all the advantages of the ALT flap without increasing donor-site morbidity. The anterior non-committal approach keeps both the ALT and the AMT flap options viable.

Elasticity of the HIV-1 Core Facilitates Nuclear Entry and Infection.

HIV-1 infection requires passage of the viral core through the nuclear pore of the cell, a process that depends on functions of the viral capsid 1,2 . Recent studies have shown that HIV- 1 cores enter the nucleus prior to capsid disassembly 3-5 . Interactions with the nuclear pore complex are necessary but not sufficient for nuclear entry, and the mechanism by which the viral core traverses the comparably sized nuclear pore is unknown. Here we show that the HIV-1 core is highly elastic and that this property is linked to nuclear entry and infectivity. Using atomic force microscopy-based approaches, we found that purified wild type cores rapidly returned to their normal conical morphology following a severe compression. Results from independently performed molecular dynamic simulations of the mature HIV-1 capsid also revealed its elastic property. Analysis of four HIV-1 capsid mutants that exhibit impaired nuclear entry revealed that the mutant viral cores are brittle. Suppressors of the mutants restored elasticity and rescued infectivity and nuclear entry. Elasticity was also reduced by treatment of cores with the capsid-targeting compound PF74 and the antiviral drug lenacapavir. Our results indicate that capsid elasticity is a fundamental property of the HIV-1 core that enables its passage through the nuclear pore complex, thereby facilitating infection. These results provide new insights into the mechanisms of HIV-1 nuclear entry and the antiviral mechanisms of HIV-1 capsid inhibitors.

T-cell replete cord transplants give superior outcomes in high-risk and relapsed/refractory pediatric myeloid malignancy.

Stem cell transplant (SCT) outcomes in high-risk and relapsed/refractory (R/R) pediatric acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) have been historically poor. Cord blood (CB) allows T-cell replete CB transplant (TRCB), enabling enhanced graft-versus-leukemia. We consecutively collected data from 367 patients undergoing TRCB (112 patients) or other cell source (255 patients) SCT for pediatric AML/MDS in the United Kingdom and Ireland between January 2014 and December 2021. Data were collected about the patient's demographics, disease, and its treatment; including previous transplant, measurable residual disease (MRD) status at transplant, human leukocyte antigen-match, relapse, death, graft versus host disease (GvHD), and transplant-related mortality (TRM). Univariable and multivariable analyses were undertaken. There was a higher incidence of poor prognosis features in the TRCB cohort: 51.4% patients were MRD positive at transplant, 46.4% had refractory disease, and 21.4% had relapsed after a previous SCT, compared with 26.1%, 8.6%, and 5.1%, respectively, in the comparator group. Event free survival was 64.1% within the TRCB cohort, 50% in MRD-positive patients, and 79% in MRD-negative patients. To allow for the imbalance in baseline characteristics, a multivariable analysis was performed where the TRCB cohort had significantly improved event free survival, time to relapse, and reduced chronic GvHD, with some evidence of improved overall survival. The effect appeared similar regardless of the MRD status. CB transplant without serotherapy may be the optimal transplant option for children with myeloid malignancy.

Applications of Atomic Force Microscopy in HIV-1 Research.

Obtaining an understanding of the mechanism underlying the interrelations between the structure and function of HIV-1 is of pivotal importance. In previous decades, this mechanism was addressed extensively in a variety of studies using conventional approaches. More recently, atomic force microscopy, which is a relatively new technique with unique capabilities, has been utilized to study HIV-1 biology. Atomic force microscopy can generate high-resolution images at the nanometer-scale and analyze the mechanical properties of individual HIV-1 virions, virus components (e.g., capsids), and infected live cells under near-physiological environments. This review describes the working principles and various imaging and analysis modes of atomic force microscopy, and elaborates on its distinctive contributions to HIV-1 research in areas such as mechanobiology and the physics of infection.

A Case of Abiraterone-Related Hypokalemia Leading to Torsades de Pointes and Cardiac Arrest.

Abiraterone acetate is an androgen-depriving therapy (ADT) that is highly effective for treating castration-resistant prostate cancer (CRPC). By inhibiting CYP17, abiraterone can induce a state of mineralocorticoid excess, which is associated with profound hypokalemia. We present a case of abiraterone-related hypokalemia which led to torsades de pointes (TdP) and ventricular fibrillation (VF). We reviewed the literature and showed the need for close monitoring of the potassium level and electrocardiogram (ECG) to prevent fatal arrhythmias.

Acyanotic Truncus Arteriosus: Not a Misnomer But a True Rarity.

Truncus arteriosus, also referred to as common arterial trunk (CAT), is generally classified as a cyanotic congenital heart disease characterized by a single arterial trunk arising from the heart and supplying both pulmonary and systemic circulations. Cyanosis exists by virtue of it being an admixture lesion. We report a 13-year-old boy diagnosed to have type 1 CAT who was acyanotic at presentation and had all features of an operable lesion even at this age. He underwent a successful repair with closure of the subtruncal VSD and insertion of a hand-sewn valved right ventricle-to-pulmonary artery conduit made of bovine pericardium and Gore-Tex membrane.

Challenges in management of an isolated intrapancreatic Common Bile Duct injury in an abdominal trauma.

INTRODUCTION: Biliary tract injuries are rare following abdominal trauma. If detected late, outcome is less favourable. It adds to morbidity if there is involvement of head of pancreas or duodenal wall. CASE REPORT: We present a case of an adult male with sharp and blunt trauma over the right side of the abdomen with omentum protruding out. Exploratory laparotomy revealed non expanding paraduodenal hematoma without evidence of solid or hollow viscous injury. Post-operative day 2 drain showed bilious content. Contrast Enhanced CT scan ruled out the solid or hollow viscous injury. Magnetic Resonance choledocopancreaticography (MRCP) done on day 4 was suggestive of isolated intrapancreatic common bile duct injury of American Association of Surgery for Trauma (AAST) grade V. Endoscopic Retrograde choledocopancreaticography (ERCP) with stenting was done. Stent removal was done after 12 weeks. The patient is asymptomatic at 1 year follow up. DISCUSSION: Due to limitations of the conventional post trauma investigations like FAST and CECT abdomen, it is likely to miss the CBD injury in the early course. MRCP is a good noninvasive investigation to diagnose the biliary injury. ERCP is considered as the most appropriate tool for the diagnosis as well as therapeutic stenting. CONCLUSION: High degree of suspicion is most important in diagnosis of the distal common bile duct trauma as imaging studies like FAST and CT scan can miss the same. MRCP is good noninvasive imaging tool to diagnose the biliary trauma, while ERCP is the best diagnostic and therapeutic tool with minimal post-operative morbidity.

Primary Squamous Cell Carcinoma of the Sternum.

Primary squamous cell carcinoma of the sternum is very rare. Imaging features are not specific, and a biopsy specimen may help identify the pathology. Positron emission tomography scan helps rule out a primary focus elsewhere. The treatment will be surgical management, if operable. We encountered a patient with primary squamous cell carcinoma of the sternum with an unusual presentation. After the diagnostic workup, we managed the patient surgically with resection, followed by titanium mesh reconstruction and pectoralis major flap cover. We present the case in view of its rarity and to emphasize the key surgical points.

Pedicled Flap vs. Free Flap Reconstruction in Head and Neck Cancers: Clinical Outcome Analysis from a Single Surgical Team.

Head and neck cancers are one of the leading causes of morbidity and mortality in Indian population. Reconstruction and restoration of function are also of paramount importance in these patients. The aim of this study was to report outcomes for free flaps and pedicle flaps in patients with oral cavity cancers. A retrospective analysis of 628 patients with oral cavity cancers who underwent reconstruction with either free flaps or pedicle flaps during 2014-2020 was done. The median age of the cohort was 49 years. The free flap reconstruction was performed in 481 (76%) and pedicle flap in 147 (24%) patients. Among free and pedicle flaps, 27 (5.6%) and 3 (2.1%) respectively had major flap complications and 25 (5.1%) and 14 (9.9%) respectively had minor complications. CCI score > 4 was associated with higher events (p = 0.02) in free flap group. The outcomes of free flaps are similar in comparison to pedicle flaps in patients with oral cavity cancers. The higher CCI score is significantly associated with increased flap-related complications for the free flap group.

Complete hemogram: simple and cost-effective in staging and predicting outcome in acute pancreatitis.

BACKGROUND: An important goal in management of acute pancreatitis (AP) is early prediction and recognition of disease severity. Various predictive scoring systems are in clinical use with their own limitations and there is always a quest for simple, practical, quantifiable, dynamic and readily available markers for predicting disease severity and outcome. Complete hemogram is routinely ordered in all patients with AP. In recent years red cell distribution width (RDW), neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR) and platelet lymphocyte ratio (PLR) have been found to be independent predictors of prognosis in various benign and malignant conditions. This prospective study evaluated complete hemogram based markers in AP. MATERIAL AND METHODS: Complete hemogram analysis was done and NLR, LMR, PLR values were calculated. Development of organ failure, the need for intensive care unit (ICU) admission and interventions, development of complications (local/systemic) and 100-day mortality were assessed. RESULTS: In this study 160 subjects of AP were included. Complete hemogram analysis was performed within 24 h after admission. C­reactive protein, RDW, NLR, PLR and bedside index of severity in acute pancreatitis (BISAP) values were higher in severe AP than moderate AP group than mild AP group, while LMR values were decreased in the corresponding severe, moderate and mild AP groups (p < 0.001). The NLR performed best for prediction of ICU admission, organ failure, interventions and mortality with area under receiver operating curve (AUROC) were 0.943, 0.940, 0.902 and 0.910, respectively. CONCLUSION: Hemogram based markers are simple, objective, dynamic and readily available. They can be considered in addition to conventional multifactorial scoring systems for prediction of outcome and prognosis of AP.

In-home neurogaming: Demonstrating the impact of valid gesture recognition method on high volume kinematic outcomes.

The process of cleaning motion capture data of aberrant points has been described as "the bane of motion capture operators". Yet, managing the high volume kinematic data generated through in-home neurogames requires data quality control that, executed insufficiently, jeopardizes accuracy of outcomes. To begin to address this issue at the intersection of biomechanics and "big data", we performed a secondary analysis of a neurogame, evaluating gesture count as well as shoulder and elbow joint angle outcomes calculated from kinematic data in which valid gestures were identified through 3 methods: visual review of regions of interest by an expert (BP); manufacturer-recommended data smoothing (MS); and automated methods (AI). We hypothesized that upper extremity kinematic outcomes from BP would be matched by AI but not MS methods. From one person with post-stroke hemiparesis, upper-extremity kinematic data were collected for 6 days over 2 weeks using a Microsoft Kinect™-based neurogame. We calculated gesture count, shoulder angle, and elbow angle outcomes from data managed using BP, MS, and AI methods. BP identified 1929 valid gestures total over 6 days which was different than the other two methods (p = 0.0015). In contrast, the AI algorithm with best precision identified 4372 and MS identified 4459 valid gestures. Furthermore, angle outcomes calculated from AI and MS methods resulted in different values than BP (p < 0.001 for 5 of 6 variables). More research is needed to automate treatment of high volume, low quality motion data to support investigation of motion associated with in-home rehabilitation neurogames.

Salmonella paratyphi A infection presenting as breast abscess.

Salmonella in a breast abscess is uncommon, and Salmonella paratyphi A causing breast abscess is a rare entity. It has been reported post immunosuppression. We report here a 35-year-old woman with breast abscess caused by S. paratyphi A without obvious enteric fever-like symptoms. The case was managed with combined surgical and medical approach to treat the aetiology and focal infection.

Unilateral ectopic breast tissue on vulva in an adult female.

Among the ectopic breasts, an ectopic breast tissue on vulva is an extremely rare case, especially in adult period. To our knowledge only 38 cases of ectopic breast tissue on vulva are documented in the world literature, out of which only 10 cases of unilateral ectopic breast tissue on vulva has been reported. Because of its rarity here we report a case of unilateral ectopic breast tissue on vulva in an adult female.

Vesicocutaneous fistula caused by giant vesical calculus.

Vesicocutaneous fistula is an extremely rare complication of vesical calculus.To our knowledge only three cases have been reported in the World literature. Because of its rarity, here we report a case of vesicocutaneous fistula caused by giant vesical calculus. This is probably the fourth case of vesicocutaneous fistula caused by giant vesical calculus.

Transverse colon volvulus with chilaiditis syndrome.

UNLABELLED: Volvulus of transverse colon is a rare cause of large bowel obstruction. To our knowledge only 75 cases have been reported in the world literature and additionally only three cases of transverse colon volvulus with Chilaiditis syndrome have been reported to date. Because of its rarity here we report a case of transverse colon volvulus which was indeed associated with Chilaiditis syndrome. This is probably the fourth case of Chilaiditis syndrome caused by transverse colon volvulus. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12262-010-0130-4) contains supplementary material, which is available to authorized users.