METHODS: Initially, total lysates of 2fTGH and U2A cells (transfected with recombinant IRF9) were filter-selected and concentrated using phosphoprotein enrichment assay. The phosphoprotein state of IRF9 was further confirmed using Phos-tag™ assay. All protein expression was determined using Western blotting. Tandem mass spectrometry was conducted on immunoprecipitated IRF9 to identify the phosphorylated amino acids. Finally, site-directed mutagenesis was performed and the effects of mutated IRF9 on relevant ISGs (i.e., USP18 and Mx1) was evaluated using qPCR.
RESULTS: IRF9 is phosphorylated at S252 and S253 under IFNβ-induced condition and R242 under non-induced condition. Site-directed mutagenesis of S252 and S253 to either alanine or aspartic acid has a modest effect on the upregulation of USP18 gene-a negative regulator of type I interferon (IFN) response-but not Mx1 gene.
CONCLUSION: Our preliminary study shows that IRF9 is phosphorylated and possibly regulates USP18 gene expression. However, further in vivo studies are needed to determine the significance of IRF9 phosphorylation.
METHOD: The study was conducted among 429 patients with essential hypertension aged > 30 years residing in four villages of a taluk/tahsil in a South Indian state. A pre-tested semi-structured questionnaire was used to collect data on socio-demographic characteristics, diagnosis and treatment of hypertension, lifestyle factors (e.g. diet and substance use), facilitators and barriers of BP control and anthropometric measurements. BP was measured using World Health Organization standards and classified using the Joint National Committee 8 Guidelines. Descriptive statistics were measured in terms of numbers and percentages. Univariate and multivariate logistic regression analyses were used to determine the significant determinants of BP control.
RESULTS: Approximately 64.3% of the participants had their BP under control. The participants aged 46-59 years were more likely to have uncontrolled BP than those aged ≥60 years. The participants with <80% adherence to medication (non-adherent) had a five fold higher odds of having uncontrolled BP than those with >80% adherence.
CONCLUSION: Adherence to medication was the only significant factor for BP control in the present study. Hence, adherence to medication should be addressed with interventions targeted to improve BP control in patients with hypertension.