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Nawani, S.

Publications and source records attributed to Nawani, S..

3 recordsLinked to original sources

Comparative Transcriptomic Analysis of Gene Expression Patterns in Neutrophils from Rheumatoid Arthritis and COVID-19

Background: Rheumatoid arthritis (RA) is an autoimmune disorder characterised by chronic inflammation and immune dysregulation, and neutrophils play a key role in its progression. COVID-19 also involves neutrophil hyperactivation that contributes to severe immune responses. Emerging evidence links COVID-19 to increased incidence or exacerbation of RA, potentially through overlapping immune mechanisms. Objective: To compare neutrophil transcriptomic profiles in RA and COVID-19 and identify shared immune pathways and disease-specific features. Methods: Publicly available neutrophil RNA-seq count data from the Gene Expression Omnibus were analysed: RA versus healthy controls (GSE116899) and COVID-19 versus healthy controls (GSE212041). A second COVID-19 comparison (severe versus convalescent) was assembled from GSE272381 and GSE227116. Differential expression was analysed with DESeq2, pathway enrichment with fgsea (Hallmark gene sets) and topGO (Gene Ontology biological process and molecular function). Differentially expressed genes (DEGs) were compared between diseases by direction of change. Results: In RA neutrophils, 11,355 DEGs were identified, of which 90 had an absolute log2 fold change of at least 2 with p<0.05 (70 upregulated, 20 downregulated). Twenty-four Hallmark gene sets were positively enriched at adjusted p<0.05, led by interferon alpha and interferon gamma responses, and Gene Ontology analysis highlighted type I interferon, antiviral and double-stranded RNA terms. In COVID-19 neutrophils, 420 DEGs were identified (37 upregulated, 383 downregulated), and no Hallmark gene set reached adjusted p<0.05. Of the 90 RA DEGs, 46 changed in the same direction in COVID-19 without reaching significance, and 27 changed significantly in the opposite direction, including CAMK1G, SIGLEC1, OAS1 and OAS3. In the second COVID-19 comparison, several of these genes, including OAS1, OAS3 and SIGLEC1, changed in the same direction as in RA. Conclusions: RA neutrophils show a transcriptional programme enriched for interferon and antiviral-response pathways. Part of the RA signature is shared with COVID-19 neutrophils, while a subset of genes diverges, and this divergence depended on the COVID-19 comparison used. These findings are hypothesis-generating and provide candidate genes for experimental validation.

bioinformatics↗

Assessment of critically endangered Northern River Terrapin (Batagur baska) phylogeny through next-generation sequencing-based mitogenome analyses

The Northern River Terrapin, Batagur baska (Gray, 1830), is a critically endangered freshwater turtle, primarily found in the estuaries and tidal regions of large rivers in South and Southeast Asia. B. baska has experienced extensive population declines and extirpations across most of its range, with no confirmed wild populations remaining. To support conservation efforts of this turtle, our study utilizes first complete mitochondrial genome of B. baska using next-generation sequencing (NGS). This mitochondrial genome data is combined with existing genetic information to evaluate the species phylogenetic position within the Geoemydidae family. The Bayesian phylogenetic analysis, including 38 species sequences, confirmed a close genetic relationship between B. baska and B. affinis (posterior probability = 1). The mitochondrial genome of B. baska consists of 16,503 base pairs, with a typical structure comprising 13 protein-coding genes, two rRNA genes, and 22 tRNA genes, along with a non-coding control region. The protein-coding genes account for 68.9% of the genome, while the ribosomal RNA and tRNA genes cover 15.4%. The control region, located between tRNAPro and tRNAPhe, is 986 bp long and exhibits a distinct base composition.

genomics↗

Sexual dimorphism in the social behaviour of Cntnap2 KO mice correlates with disrupted synaptic connectivity and increased microglial activity in the anterior cingulate cortex of males

A biological understanding of the apparent sex bias in autism is lacking. We have identified Cntnap2 KO mice as a model system to help better understand this dimorphism. Using this model, we observed social deficits in juvenile male KO mice only. These male-specific social deficits correlated with reduced spine densities of Layer 2/3 and Layer 5 pyramidal neurons in the Anterior Cingulate Cortex, a forebrain region prominently associated with the control of social behaviour. Furthermore, in male KO mice, microglia showed an increased activated morphology and phagocytosis of synaptic structures compared to WT mice, whereas no differences were seen in female KO and WT mice. Our data suggest that sexually dimorphic microglial activity may be involved in the aetiology of ASD, disrupting the development of neural circuits that control social behaviour by overpruning synapses at a developmentally critical period.

neuroscience↗