The rearrangement of the actin cytoskeleton has been shown to play a critical role in the development of transformation and malignant phenotype of cancer cells. Rho family GTPases regulate the arrangement of the actin cytoskeleton. By wound-healing assay, we have found that NIH 3T3 fibroblast cells move towards the wound- gaps by extending filopodial and lamellipdial structures at the leading edge of the moving cells. We have inactivated the function of Rho GTPases of v-Ras transformed NIH 3T3 cells by overexpressing Rho GTPase-activating (RhoGAP) domain of RhoGAP of p190. We have observed that inactivation of Rho, Rac and Cdc42 GTPases by overexpressing RHG causes inhibition of: (i) polymerization of actin to form filaments, (ii) formation of lamellipodia, filopodia and stress fibres, (iii) cell motility, (iv) cell spreading and (v) cell-to-cell adhesions. These results further strengthen the current knowledge on the role of Rho, Rac and Cdc42 GTPases in the regulation of the rearrangement of actin cytoskeleton. Our results, for the first time, demonstrate that RhoGAP domain of RhoGAP could be used to study the molecular mechanism of Ras-mediated signalling in growth, differentiation and carcinogenesis.
Animals ; Biological Assay ; Cell Line, Transformed ; Cell Movement/*physiology ; Cell Transformation, Neoplastic/*ultrastructure ; Mice ; Microfilaments/metabolism/*ultrastructure ; NIH 3T3 Cells ; Research Support, Non-U.S. Gov't ; Wound Healing ; rho GTP-Binding Proteins/genetics/*physiology

Introduction: Vitamin A deficiency is one of the most serious health problems in developing countries. This study aims to explore the comparative figure of vitamin A knowledge, household consumption frequency of vitamin A-rich foods, and association of socio-demographic factors with knowledge and consumption in four residential areas in Tangail district, Bangladesh. Methods: This study used a population-based cross-sectional design with 400 study participants selected using purposive sampling technique. Knowledge and consumption frequency were assessed by a structured questionnaire along with food frequency table. Data were analysed using descriptive statistics. Results: Only 33.5% participants had primary vitamin A knowledge, where most from urban (48.5%) and semi-urban (30.6%) areas had comparatively higher knowledge than those from rural (11.2%) and slum (9.7%) areas. Specific knowledge level was also poorer in rural and slum areas than urban and semi-urban areas. Most of the participants received knowledge through commercial advertisements (65.7%). Household consumption frequency of vitamin A-rich foods (plant and animal) was comparatively lower in rural and slum areas than in urban and semi-urban areas. Different socio-demographic factors (place of residence, education and household income) significantly influenced participant’s vitamin A knowledge and household consumption of vitamin A-rich foods (p<0.05). Conclusion: In general, the study population lacked knowledge regarding the importance of vitamin A. Consumption frequency of vitamin A-rich foods was still poorer in slum and rural areas than in urban and semi-urban areas.

Dengue is a public health issue in tropical south-eastern Asia responsible for significant morbidity and mortality. Information on dengue epidemiology is necessary for developing strategies to control infections effectively. In the Lao People’s Democratic Republic (Lao PDR), Champasak and Savannakhet provinces account for around 30% of the national dengue burden. In this study, the dengue epidemiological profile in these two southern provinces of Lao PDR was described by analysing seasonal and spatial dengue notification data from 2003–2020 using the long-term mean (LTM) method. Savannakhet had a higher LTM (132.0 cases/month, 95% confidence interval [Cl]: 92.2–171.7) than Champasak (113.3 cases/month, 95% CI: 86.0–140.5), with peaks in dengue notifications following the rainy season in both provinces. The highest notification rates were observed in July to September; these months were also when the LTM was most frequently exceeded. Previously, dengue notifications were largely confined to the western districts of Savannakhet and the northern districts of Champasak, but more recently, notifications have increased in the eastern districts of Savannakhet and southern districts of Champasak. While the notification rate remained high in children and young adults (5–30 years), especially among students and farmers, a shift in the age structure of dengue cases was observed, with a greater proportion of notifications now occurring in those aged over 30 years. Community-based vector control and prevention programmes are needed to restrict the spread of dengue into new geographical areas in the southern provinces of Lao PDR.