The role of Rho GTPases in the regulation of the rearrangement of actin cytoskeleton and cell movement

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.

Helicobacter pylori: prevalence, clinical and endoscopic findings in children who underwnet upper endoscopy for abdominal ailments

A total of 97 children aged 1 month to 16 years (mean 6.6 years) had upper endoscopies performed in Paediatric Institute, Kuala Lumpur Hospital between January 1997 and December 1999 for various gastrointestinal symptoms. Of these 70 children were tested for Helicobacter pylori. The four most common indications for upper endoscopy were recurrent abdominal pain, upper gastrointestinal bleeding, epigastric pain and vomiting. The overall prevalence of this infection in this heterogenous group of symptomatic children was 10% (7/70). This study shows that H.pylori positivity in a routine endoscopy population is low and does not appear to be associated with specific symptoms.

Percutaneous drainage of amoebic liver abscess

This prospective study of 12 patients of amoebic liver abscess presenting to the department of Surgery, Shaikh Zayed Hospital, Lahore, over a one year period evaluates the results of ultrasound-guided percutaneous drainage of large amoebic liver abscesses. The results indicate short hospital stay, no mortality and minimal morbidity. This procedure may be safely recommended as the preferred primary method of managing ameobic abcesses larger than 6cm in diameter

Hydatid cyst of breast

Hydatid disease of the breast is very uncommon. This study described the plain film, mammographic and ultra-sonographic pattern in two proved cases of hydatid cyst of breast, with review of literature