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This study aimed to determine the diagnostic yield of fine-needle aspiration cytology (FNAC) in salivary gland lesions compared to histopathological diagnosis. The present study was done on patients above 18 years of age, with a palpable swelling, who are clinically diagnosed as salivary gland lesions were evaluated. A total of 31 patients were evaluated in this study. The mean age of the patients was 41 years ± 16.08. The male to female ratio of patients evaluated in our study was 1: 1.066, with a marginal preponderance in the female population. There was a higher incidence of carcinoma in females than males. Parotid gland lesions comprised 83.9% of all the salivary gland lesions analyzed, while submandibular gland lesions comprised 16.1%. In our study, the distribution between non-neoplastic, neoplastic benign, and neoplastic malignant lesions was 9.6%, 83.8%, and 6.4%. The overall diagnostic accuracy for non-neoplastic and neoplastic lesions is 90.3%, with a sensitivity of 89% and a specificity of 100%. The segregation of the results into the positive and negative class of diagnostic outcomes shows 80.6% for true positive, 9.7% for true negative, 0% for false-positive, and 9.7% for false-negative reports. Diagnostic accuracy in differentiating non-neoplastic and neoplastic lesions is 90.3%, with a sensitivity and specificity of 89.0% and 100%, respectively. The diagnostic accuracy of FNAC in differentiating benign from malignant lesions in our study is 93.5% (29 out of 31), the sensitivity of FNAC in our study for diagnosing malignancy is poor, and the specificity is 100%. It can be concluded that FNAC is more accurate in diagnosing benign lesions and more specific than sensitive in diagnosing malignant lesions., Competing Interests: Conflict of interestThe authors declare that they have a conflict of interest., (© Association of Otolaryngologists of India 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Contrary to dogma, evolutionarily young and dynamic genes can encode essential functions. We find that evolutionarily dynamic ZAD-ZNF genes, which encode the most abundant class of insect transcription factors, are more likely to encode essential functions in Drosophila melanogaster than ancient, conserved ZAD-ZNF genes. We focus on the Nicknack ZAD-ZNF gene, which is evolutionarily young, poorly retained in Drosophila species, and evolves under strong positive selection. Yet we find that it is necessary for larval development in D. melanogaster. We show that Nicknack encodes a heterochromatin-localizing protein like its paralog Oddjob , also an evolutionarily dynamic yet essential ZAD-ZNF gene. We find that the divergent D. simulans Nicknack protein can still localize to D. melanogaster heterochromatin and rescue viability of female but not male Nicknack- null D. melanogaster . Our findings suggest that innovation for rapidly changing heterochromatin functions might generally explain the essentiality of many evolutionarily dynamic ZAD-ZNF genes in insects., Competing Interests: BK, SC, HM, JY, GK, HM No competing interests declared, (© 2020, Kasinathan et al.)

The human double-homeodomain retrogene DUX4 is expressed in the testis and epigenetically repressed in somatic tissues. Facioscapulohumeral muscular dystrophy (FSHD) is caused by mutations that decrease the epigenetic repression of DUX4 in somatic tissues and result in mis-expression of this transcription factor in skeletal muscle. DUX4 binds sites in the human genome that contain a double-homeobox sequence motif, including sites in unique regions of the genome as well as many sites in repetitive elements. Using ChIP-seq and RNA-seq on myoblasts transduced with DUX4 we show that DUX4 binds and activates transcription of mammalian apparent LTR-retrotransposons (MaLRs), endogenous retrovirus (ERVL and ERVK) elements, and pericentromeric satellite HSATII sequences. Some DUX4-activated MaLR and ERV elements create novel promoters for genes, long non-coding RNAs, and antisense transcripts. Many of these novel transcripts are expressed in FSHD muscle cells but not control cells, and thus might contribute to FSHD pathology. For example, HEY1, a repressor of myogenesis, is activated by DUX4 through a MaLR promoter. DUX4-bound motifs, including those in repetitive elements, show evolutionary conservation and some repeat-initiated transcripts are expressed in healthy testis, the normal expression site of DUX4, but more rarely in other somatic tissues. Testis expression patterns are known to have evolved rapidly in mammals, but the mechanisms behind this rapid change have not yet been identified: our results suggest that mobilization of MaLR and ERV elements during mammalian evolution altered germline gene expression patterns through transcriptional activation by DUX4. Our findings demonstrate a role for DUX4 and repetitive elements in mammalian germline evolution and in FSHD muscular dystrophy., Competing Interests: The authors have declared that no competing interests exist.

During meiosis, evolutionarily conserved mechanisms regulate chromosome remodeling, leading to the formation of a tight bivalent structure. This bivalent, a linked pair of homologous chromosomes, is essential for proper chromosome segregation in meiosis. The formation of a tight bivalent involves chromosome condensation and restructuring around the crossover. The synaptonemal complex (SC), which mediates homologous chromosome association before crossover formation, disassembles concurrently with increased condensation during bivalent remodeling. Both chromosome condensation and SC disassembly are likely critical steps in acquiring functional bivalent structure. The mechanisms controlling SC disassembly, however, remain unclear. Here we identify akir-1 as a gene involved in key events of meiotic prophase I in Caenorhabditis elegans. AKIR-1 is a protein conserved among metazoans that lacks any previously known function in meiosis. We show that akir-1 mutants exhibit severe meiotic defects in late prophase I, including improper disassembly of the SC and aberrant chromosome condensation, independently of the condensin complexes. These late-prophase defects then lead to aberrant reconfiguring of the bivalent. The meiotic divisions are delayed in akir-1 mutants and are accompanied by lagging chromosomes. Our analysis therefore provides evidence for an important role of proper SC disassembly in configuring a functional bivalent structure.