No abstract available.
Ligamentum Flavum

Epithelioid hemangioma (EH) is a rare benign vascular lesion of soft tissue and bone, characterized by endothelial cells with epithelioid or histiocytoid appearance. Though tubular bones, flat bones, vertebra and short bones are common sites for this lesion, the epiphyseal involvement is extremely rare. We present an unusual case of EH of the distal femur in a young boy. Case report: A 12-year-old boy who had congenital talipes equinovarus of the right foot presented with progressively increasing pain in the right lower thigh for six months. Physical examination revealed muscular atrophy of the right lower limb and a moderately tender swelling in the medial aspect of the right knee without restriction of knee movement. An X-ray revealed an osteolytic lesion, which appeared iso- and hypointense on T1W and hyperintense on T2W MRI images in the distal epiphysis and adjacent metaphysis of the right femur. A radiological diagnosis of chondroblastoma was entertained. The patient was treated with curettage and bone grafting. Histopathology showed a tumor composed of thin-walled arteriolar capillaries lined by large, polyhedral epithelioid endothelial cells with vesicular nuclei, finely distributed nuclear chromatin, and moderate amount of eosinophilic cytoplasm. The endothelial cells were strongly immunopositive for CD34. Mitotic activity was low and the Ki-67 proliferative rate was <2%. A diagnosis of EH was made. EH is a benign lesion and it should be differentiated from its histologically similar malignant counterparts such as epithelioid hemangioendothelioma and epithelioid angiosarcoma as the lesion can be successfully treated with curettage or resection.

Non-syndromic hearing loss (NSHL) is a common hereditary disorder. Both clinical and genetic heterogeneity has created many obstacles to understanding the causes of NSHL. The present study has attempted to ravel the genetic aetiology in NSHL progression and to screen out potential target genes using computational approaches. The reported NSHL target genes (2009‒2020) have been studied by analyzing different biochemical and signaling pathways, interpretation of their functional association network, and discovery of important regulatory interactions with three previously established miRNAs in the human inner ear as well as in NSHL such as miR-183, miR-182, and miR-96. This study has identified SMAD4 and SNAI2 as the most putative target genes of NSHL. But pathogenic and deleterious non-synonymous single nucleotide polymorphisms (nsSNP) discovered within SMAD4 is anticipated to have an impact on NSHL progression. Additionally, the identified deleterious variants in the functional domains of SMAD4 added a supportive clue for further study. Thus, the identified deleterious variant i.e., rs377767367 (G491V) in SMAD4 needs further clinical validation. The present outcomes would provide insights into the genetics of NSHL progression.