Construction and Characterization of a PGN_0297 Mutant of Porphyromonas gingivalis: Evidence of the Contribution of PGN_0297 to Gingipain Activity.

The periodontal pathogen Porphyromonas gingivalis shows colonial pigmentation on blood agar and produces gingipains (Kgp, RgpA, and RgpB), cysteine proteases involved in an organism's virulence and pigmentation. We showed previously that deletion of the PGN_0300 gene abolished the pigmentation activity and reduced the proteolytic activity of gingipains. The role of the PGN_0297 gene, which consists of an operon with the PGN_0300 gene, is unclear. Herein we examined the effect of PGN_0297 gene deletion on the pigmentation and proteolytic activities and transcriptional levels of gingipains. A PGN_0297 gene deletion mutant (ΔPGN_0297) did not exhibit the pigmentation. The proteolytic activity of the gingipains was decreased in the culture supernatant and on the cell surface of ΔPGN_0297. The mutant ΔPGN_0297 failed to attenuate Akt phosphorylation at Thr308 and Ser473, but both phosphorylations were attenuated in the wild-type and its complementation strain. The deletion of PGN_0297 gene did not substantially affect the transcriptional levels of the gingipain genes kgp, rgpA, and rgpB. Taken together, these results indicate that PGN_0297 is closely involved in the secretion and maturation of gingipains.

The Influence of Atopic Dermatitis on Health-Related Quality of Life in Bangladesh.

Atopic dermatitis (AD) is the foremost non-fatal skin-related disease that affects all age groups. Despite the growing prevalence of AD in low- and middle-income countries, its physiological consequences remain overlooked in countries like Bangladesh. Therefore, we aim to assess and characterize the influence of AD on the health-related quality of life (HRQoL) in Bangladeshi patients. A cross-sectional study comprising 184 eligible adults (83 men and 101 women; mean age, 33.46 ± 15.44 years) was conducted at the dermatology outpatient department of Shaheed Suhrawardy Medical College Hospital (a tertiary hospital in Dhaka, Bangladesh). AD was determined using the UK Working Party criteria. A structured questionnaire, Eczema Area and Severity Index (EASI), and Dermatology Life Quality Index (DLQI) were administered to obtain information on patient characteristics, AD severity, and HRQoL. The mean DLQI score for the entire sample was 11.29 ± 5.27 (range, 1-26), and 51.60% reported the disease greatly affected their lives. Bivariate analysis revealed significant differences in self-rated health measures of DLQI scores in terms of self-reported AD severity, overall health, and the EASI. In multivariable regression models adjusted for patient characteristics, the self-perceived severe AD group reported significantly higher DLQI scores (coefficient = 2.72; 95% confidence interval (CI) = 0.38-5.05; p = 0.022) than the mild group. Concurrently, we observed a substantial increase in the DLQI scores among patients with moderate and severe EASI scores (coefficient = 1.96, 95% CI = 0.08-3.92, p < 0.05 and coefficient = 4.35, 95% CI = 1.98-6.72, p < 0.001, respectively) than in those with mild EASI scores, suggesting that HRQoL was markedly influenced by greater AD severity. These findings highlight the need for a more patient-centric approach to the management of AD in order to alleviate patient suffering and, thereby, improve HRQoL.

Construction and characterization of the PGN_0296 mutant of Porphyromonas gingivalis.

The periodontal pathogen Porphyromonas gingivalis produces gingipains (Kgp, RgpA, and RgpB), cysteine proteases involved in the organism's virulence, and pigmentation. We previously showed that deletion of the PGN_0297 and PGN_0300 genes reduced the proteolytic activity of gingipains. The role of the PGN_0296 gene, consisting of an operon with the PGN_0297 and PGN_0300 genes, is unclear. Herein, we examined the effect of PGN_0296 gene deletion on the proteolytic activity. Although the proteolytic activity of the gingipains did not decrease in the culture supernatant of a PGN_0296 gene deletion mutant (ΔPGN_0296), the growth was delayed.