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Background: Schwannoma and neurofibroma constitute benign peripheral nerve sheath tumors (BPNSTs), which may present as single or multiple lesions. Multiple schwannomas are rare in the peripheral nerves of the upper extremity. Solitary small schwannoma is usually asymptomatic, while larger and multiple schwannomas may have different symptoms due to pressure effects. Median and ulnar nerve communications are often encountered in the upper limb, making these anastomoses clinically important. However, such communications with schwannomas in the axilla are rare. Case Report: The study protocol was designed per the prevailing guidelines of the Institute on the use of human cadavers for teaching and research. Written informed consent was obtained from the family of the body donor at the time of whole-body donation. The upper extremities, including the brachial plexuses of both sides, were carefully dissected as per the instructions in Cunningham’s Manual of Practical Anatomy15th edition. Discussion: Unusual anastomoses in the axilla and two encapsulated, highly vascular fusiform masses were observed. Another fairly large mass was noted on the right chest wall. Histological examination confirmed the masses to be schwannomas. Conclusion: Asymptomatic schwannomas often remain undiagnosed, and those lying in the axilla can be misdiagnosed. Awareness of such variant anatomy will enable clinicians and surgeons to plan more appropriate diagnostic and therapeutic interventions. [ABSTRACT FROM AUTHOR]

Context: SARS-CoV-2 virus causes COVID-19 by infecting nasal and oral cavities primarily by attaching its spike proteins to ACE 2 receptors expressed in epithelial cells. Aim: This study was done to evaluate the micronucleated cell count, metanuclear abnormalities, and genotoxic factor in exfoliated buccal mucosal cell among the COVID-19 suspected patients. Settings and Design: This cross-sectional study was conducted at AIIMS, Mangalagiri, between August and October 2022. Methods: One hundred COVID-19 suspected patients were recruited for this study after obtaining informed and written consent; buccal smear was obtained and stained for papanicolaou test (PAP). The PAP-stained slides were analyzed for micronuclei (MN), pyknotic, karyolytic, and karyorrhexic cell count, respectively. Based on their reverse transcription-polymerase chain reaction (RT-PCR) report, the patients were grouped into COVID-19 positive and negative groups. Statistical Analysis: The genotoxicity factor was calculated using the micronucleated cell count from both the groups using mean and standard deviation. Results: The MN, micronucleated cell, pyknotic, karyolitic, and karyorrhexic cell count in COVID-19 positive patients were 24.12, 15.24, 3.08, 2.88 and 4.40, respectively, than COVID-19 negative patients 5.69, 8.17, 1.08, 1.00 and 2.43, respectively. The genotoxicity factor for SARS-CoV-2 was 2.68 which is a positive genotoxic effect on buccal mucosal cells. Conclusion: SARS-CoV-2 increases the expression of micronucleated cells, pyknotic cells, karyolytic cells, and karyorhexic cells and concludes SARS-CoV-2 is having cytogenotoxic effect on the buccal mucosal cells. This can be used as a reliable marker in identifying the early carcinogenic effects of virus causing COVID-19. [ABSTRACT FROM AUTHOR]

COVID-19 pandemic has been a global health emergency due to its association with severe pneumonia and high rate of mortality. In the current study, we reported the direct evidence for the variable level of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infection on several types of oral epithelial cells isolated from the aspirated oropharyngeal and bronchoalveolar secretions of severely infected and intubated patients using cytology, confocal based immunofluorescence imaging (IF), scanning electron microscope (SEM) and transmission electron microscopic (TEM) studies. Cytological analysis showed the presence of keratinised and non-keratinised oral epithelial cells with viral inclusion bodies in stratum granulosum and intermedium cells. IF imaging using SARS-CoV-2 spike protein specific antibody confirmed the presence of virus inside the stratum spinosum/granulosum (keratinised) and stratum intermedium/superficial cells (non-keratinised). No SARS-CoV-2 viruses were seen in stratum corneum cells. SEM analysis also confirms the absence of virus like structure on stratum corneum surface while viruses like structure were seen on the stratum spinosum/granulosum/stratum/intermedium and stratum superficial cells. This advanced microscopic study confirms directly that the virus tends to infect and multiply in the metabolically active or sub-basal cells of oral epithelium and absent in the inactive keratinised stratum corneum from shedding zones of oral mucosa. [ABSTRACT FROM AUTHOR]

Ypr147cp of Saccharomyces cerevisiae was localized to lipid droplets. The recombinant Ypr147cp showed both triacylglycerol lipase and ester hydrolase activities. Knock out of YPR147C led to accumulation of TAG in ypr147cΔ when compared to wild type (WT). Transmission electron microscopic analysis of ypr147cΔ cells show increased lipid bodies. Moreover, the lipid profiling confirmed the accumulation of fatty acids derived from neutral and phospholipids in ypr147cΔ cells. Sequence analysis of Ypr147cp show the presence of an a/b hydrolase domain with the conserved GXSXG lipase motif. The YPR147c homology model was built and the modeled protein was analysed using RMSD and root mean square fluctuation (RMSF) for a 100 ns simulation trajectory. Docking the acetate, butyrate and palmitate ligands with the model confirmed covalent binding of ligands with the Ser207 of the GXSXG motif. Thus, Ypr147cp is a lipid droplet associated triacylglycerol lipase having short chain ester hydrolyzing capacity., (© 2021 Biomedical Informatics.)