Role of Telemedicine in Otorhinolaryngology during COVID-19 Pandemic in a Tertiary Care Centre of Tamil Nadu: A Prospective Cohort Study

Introduction: Telemedicine is the practice of using telecommunication technology to provide healthcare services to patients in remote areas. Teleconsultation is used in various specialties of medicine, especially during the COVID-19 pandemic situation. But in developing countries like India, it is less practicable in surgical specialties like Otorhinolaryngology. Aim: To determine the eligibility and effectiveness of telemedicine practice in otorhinolaryngology during the COVID-19 pandemic in a tertiary care centre of Chengalpattu district, Tamil Nadu, India. Materials and Methods: A prospective cohort study was conducted at Chettinad Hospital and Research Institute, Tamil Nadu, India from September 2021 to February 2022 which involved 90 patients who requested a consultation for various ear, nose, and throat complaints. Based on history, a provisional diagnosis was made and treated. Feedback forms contained 11 questions were sent during the revisit and analyses were made. Statistical analysis were done using mean, proportion and Chi-square test. Results: This study included 49 (54.4%) male and 41 (45.6%) female patients with a mean age of 40.68 years. Only 23 (25.6%) patients had no problem seeing the doctor clearly and 19 (21.1%) had no trouble hearing the doctor. Only 4 (4.4%) patients accepted teleconsultation and will use teleconsultation services again. Conclusion: This study concluded that teleconsultation practice was not satisfactory for the majority of patients in the field of otorhinolaryngology. The inability to arrive at the definitive diagnosis and subsequent therapeutic procedures by using telemedicine was the limitation

Ultrahard carbon film from epitaxial two-layer graphene

Atomically thin graphene exhibits fascinating mechanical properties, although its hardness and transverse stiffness are inferior to those of diamond. To date, there hasn't been any practical demonstration of the transformation of multi-layer graphene into diamond-like ultra-hard structures. Here we show that at room temperature and after nano-indentation, two-layer graphene on SiC(0001) exhibits a transverse stiffness and hardness comparable to diamond, resisting to perforation with a diamond indenter, and showing a reversible drop in electrical conductivity upon indentation. Density functional theory calculations suggest that upon compression, the two-layer graphene film transforms into a diamond-like film, producing both elastic deformations and sp2-to-sp3 chemical changes. Experiments and calculations show that this reversible phase change is not observed for a single buffer layer on SiC or graphene films thicker than 3 to 5 layers. Indeed, calculations show that whereas in two-layer graphene layer-stacking configuration controls the conformation of the diamond-like film, in a multilayer film it hinders the phase transformation.Comment: Published online on Nature Nanotechnology on December 18, 201

Protein kinase C activation disrupts epithelial apical junctions via ROCK-II dependent stimulation of actomyosin contractility

<p>Abstract</p> <p>Background</p> <p>Disruption of epithelial cell-cell adhesions represents an early and important stage in tumor metastasis. This process can be modeled <it>in vitro </it>by exposing cells to chemical tumor promoters, phorbol esters and octylindolactam-V (OI-V), known to activate protein kinase C (PKC). However, molecular events mediating PKC-dependent disruption of epithelial cell-cell contact remain poorly understood. In the present study we investigate mechanisms by which PKC activation induces disassembly of tight junctions (TJs) and adherens junctions (AJs) in a model pancreatic epithelium.</p> <p>Results</p> <p>Exposure of HPAF-II human pancreatic adenocarcinoma cell monolayers to either OI-V or 12-O-tetradecanoylphorbol-13-acetate caused rapid disruption and internalization of AJs and TJs. Activity of classical PKC isoenzymes was responsible for the loss of cell-cell contacts which was accompanied by cell rounding, phosphorylation and relocalization of the F-actin motor nonmuscle myosin (NM) II. The OI-V-induced disruption of AJs and TJs was prevented by either pharmacological inhibition of NM II with blebbistatin or by siRNA-mediated downregulation of NM IIA. Furthermore, AJ/TJ disassembly was attenuated by inhibition of Rho-associated kinase (ROCK) II, but was insensitive to blockage of MLCK, calmodulin, ERK1/2, caspases and RhoA GTPase.</p> <p>Conclusion</p> <p>Our data suggest that stimulation of PKC disrupts epithelial apical junctions via ROCK-II dependent activation of NM II, which increases contractility of perijunctional actin filaments. This mechanism is likely to be important for cancer cell dissociation and tumor metastasis.</p

Lowe Syndrome Protein OCRL1 Supports Maturation of Polarized Epithelial Cells

Mutations in the inositol polyphosphate 5-phosphatase OCRL1 cause Lowe Syndrome, leading to cataracts, mental retardation and renal failure. We noted that cell types affected in Lowe Syndrome are highly polarized, and therefore we studied OCRL1 in epithelial cells as they mature from isolated individual cells into polarized sheets and cysts with extensive communication between neighbouring cells. We show that a proportion of OCRL1 targets intercellular junctions at the early stages of their formation, co-localizing both with adherens junctional components and with tight junctional components. Correlating with this distribution, OCRL1 forms complexes with junctional components α-catenin and zonula occludens (ZO)-1/2/3. Depletion of OCRL1 in epithelial cells growing as a sheet inhibits maturation; cells remain flat, fail to polarize apical markers and also show reduced proliferation. The effect on shape is reverted by re-expressed OCRL1 and requires the 5′-phosphatase domain, indicating that down-regulation of 5-phosphorylated inositides is necessary for epithelial development. The effect of OCRL1 in epithelial maturation is seen more strongly in 3-dimensional cultures, where epithelial cells lacking OCRL1 not only fail to form a central lumen, but also do not have the correct intracellular distribution of ZO-1, suggesting that OCRL1 functions early in the maturation of intercellular junctions when cells grow as cysts. A role of OCRL1 in junctions of polarized cells may explain the pattern of organs affected in Lowe Syndrome

ICAR: endoscopic skull‐base surgery

n/

Minimal under-correction gives better outcomes following total knee arthroplasty in severe varus knees—myth or reality?—analysis of one hundred sixty two knees with varus greater than fifteen degrees

Purpose of the study To document and compare the functional outcome of neutral alignment and under-correction after total knee arthroplasty (TKA) in severe varus knees of more than 15° at three and 12 months post-surgery. Materials and methods One hundred twenty-four consecutive patients (163 TKAs) of an average age of 61.9 years (52–79) with a pre-operative varus more than 15° were managed with jig-based TKA. Based on the post-operative mechanical femorotibial alignment (FTMA), they were categorised into three groups, namely neutral (180 + 3°), mild varus (173° to 176°) and severe varus (172° and below). The outcomes of these three groups were assessed at three and 12 months by the Oxford knee score and the WOMAC score were calculated and co-related to the extent of correction. Results At three months, knees in the mild varus group (n = 88) had the best results with an Oxford knee score of 41.76 + 1.44 and a WOMAC score of 19.29 + 2.93 compared to the severe varus group and the neutral alignment group which had Oxford knee scores (OKS) of 37.43 + 2.51 and 31.91 + 3.51 and WOMAC scores of 22.57 + 1.51 and 24.46 + 4.15 respectively. However at 12 months, knees in all the groups (neutral, mild varus, severe varus) had similar good functional outcomes with OKS of 39.08 + 1.68, 39.24 + 1.88, 39.29 + 1.11 and WOMAC scores of 17.42 + 2.15, 16.48 + 2.11, 16.14 + 1.21 respectively. A scatter plot done for post-operative FTMA and the functional outcome score for both scores showed a bell curve with the best outcome corresponding to a FTMA of 175° at 3 months and equal distribution for both scores at 12 months. Conclusion The results of our study showed that minimal under-correction gave superior functional outcomes at three months. But this advantage was temporary and both, under-correction and neutral alignment achieved equally good outcomes at one year. Considering the increased prosthesis longevity associated with neutral alignment, we propose that neutral alignment must be aimed for during TKA for knees with severe varus. Study Design Prospective study</p

Megaprosthesis in distal femur nonunions in elderly patients—experience from twenty four cases

Purpose of the study To evaluate the outcomes and complications using cemented megaprosthesis in elderly patients with distal femur nonunions (DFN). Materials and methods Between 2012 and 2016, 24 patients of DFN with an average age of 71.8 years (66–83) and an average 1.9(1–3) prior surgery was managed with distal femur replacement using cemented modular endoprosthesis. Outcomes were analysed on the following criteria: implant status, complications, knee range of motion, Knee Society Score (KSS) and Musculoskeletal Tumor Society (MSTS) score. Results All patients were extremely satisfied with their outcomes. At an average 22.1 months (10–43) follow-up, patients had an average 69.5° (40°-110°) knee flexion, an average KSS of 75.7 (63–88) and an average MSTS score of 19.3 (17–25). Four patients died at an average 21.3 months after surgery due to causes unrelated to the fracture. One patient (4.1%) had implant-related complication; deep infection which required debridement and intravenous antibiotics. There were no late amputations or peri-operative deaths and no patient had aseptic loosening of components. Conclusion By permitting immediate full weight-bearing ambulation and with most patients returning to an acceptable functional status, cemented megaprosthesis is a viable and useful single-stage management option in elderly patients with DFN.</p

Surgical management of primary bone sarcomas

This article aims to address the principles of surgical treatment of primary bone sarcomas including chondrosarcoma, osteosarcoma and Ewing's sarcoma of bone. This piece is aimed at serving as a guide to experienced orthopaedic surgeons who have limited knowledge of dealing with musculoskeletal tumours especially primary bone sarcomas. Important principles surrounding surgery involving bone sarcomas, principles of biopsy of such lesions and reconstruction techniques have been discussed. Limb salvage is the way forward in today's era and though endoprosthesis replacement is an important tool in a surgeon's armoury, biological methods of reconstruction have also shown to be effective in many settings. Chemotherapy and radiotherapy are vital adjuvant therapies associated with these sarcomas, and they have been discussed in this article