We recently showed that phanoside, a gypenoside isolated from the plant Gynostemma pentaphyllum, stimulates insulin secretion from rat pancreatic islets. To study the mechanisms by which phanoside stimulates insulin secretion. Isolated pancreatic islets of normal Wistar (W) rats and spontaneously diabetic Goto-Kakizaki (GK) rats were batch incubated or perifused. At both 3 . 3 and 16 . 7 mM glucose, phanoside stimulated insulin secretion several fold in both W and diabetic GK rat islets. In perifusion of W islets, phanoside (75 and 150 mM) dose dependently increased insulin secretion that returned to basal levels when phanoside was omitted.When W rat islets were incubated at 3 . 3 mM glucose with 150 mM phanoside and 0 . 25 mM diazoxide to keep K-ATP channels open, insulin secretion was similar to that in islets incubated in 150 mM phanoside alone. At 16 . 7 mM glucose, phanoside-stimulated insulin secretion was reduced in the presence of 0 . 25 mM diazoxide (P!0 . 01). In W islets depolarized by 50 mM KCl and with diazoxide, phanoside stimulated insulin release twofold at 3 . 3 mM glucose but did not further increase the release at 16 . 7 mM glucose.When using nimodipine to block L-type Ca 2C channels in B-cells, phanoside-induced insulin secretion was unaffected at 3 . 3 mM glucose but decreased at 16 . 7 mM glucose (P!0 . 01). Pretreatment of islets with pertussis toxin to inhibit exocytotic G e -protein did not affect insulin response to 150 mM phanoside. Phanoside stimulated insulin secretion from Wand GK rat islets. This effect seems to be exerted distal to K-ATP channels and L-type Ca 2C channels, which is on the exocytotic machinery of the B-cells.

Uropathogenic Escherichia coli (UPEC) carry many virulence factors, including those involved in long-term survival in the urinary tract. However, their prevalence and role among UPEC causing urinary tract infection (UTI) in children is not well studied. To further understand the virulence characteristics of these bacteria, we investigated the prevalence of antibiotic resistance, antigen 43 genes, curli and cellulose among UPEC in children from different countries. Isolates (n = 337) from five countries were tested for antibiotic susceptibility, phylogenetic groups, prevalence of flu, fluA(CFT073), fluB(CFT073), curli and cellulose. High prevalence of multidrug resistance and extended spectrum beta lactamase production was found among Iranian and Vietnamese isolates. Resistance was associated with phylogenetic group D while group B2 was associated with fluA(CFT073) and fluB(CFT073). Fewer Iranian isolates carried fluA(CFT073), curli and cellulose. fluB(CFT073) was most prevalent among Slovak isolates. Ampicillin and amoxicillin/clavulanic acid resistance was prevalent among fluA(CFT073)- and fluB(CFT073)-positive Australian, Iranian and Swedish isolates. Lack of curli and cellulose was associated with resistance among Vietnamese isolates. We conclude that major differences exist in the prevalence of antibiotic resistance among UPEC from different countries. Associations observed between resistance and virulence factors may, in different ways, promote the long-term survival of UPEC in the urinary tract.

Urinary tract infection (UTI) is common during pregnancy and can be associated with negative outcomes for both the mother and fetus. Increased risk of infection among these patients has been attributed to physiological changes, and less focus has been placed on Escherichia coli, the most frequent causative agent. We investigated the virulence properties of isolates causing UTI in pregnant women in Sweden, Uganda, and Vietnam, as well as nonpregnant women in Sweden. Although phylogenetic group B2 was the most prevalent group, more Ugandan isolates belonged to group B1, associated with commensal strains, than isolates from other countries. Adherence to and invasion of urothelial cells, key events in the infection process, were low among group B1 isolates from pregnant Swedish women compared to those from nonpregnant patients. Similar levels of adherence and invasion were seen in isolates from pregnant women in Uganda and Vietnam. More biofilm was formed by group B2 isolates than by those belonging to group B1 and by Ugandan group B2 isolates than by those from pregnant Swedish and Vietnamese women. The antigen 43a-encoding gene, fluA CFT073 , was most prevalent among Ugandan isolates. Expression of the biofilm components, curli and cellulose, was low among all isolates. Multidrug resistance was more common among isolates from Uganda and Vietnam than among those from Swedish patients. We suggest that while bacterial virulence properties play an important role in UTI during pregnancy, physiological changes in the host may contribute more to the incidence of infection caused by less virulent E. coli. U rinary tract infection (UTI) is the predominant type of bacterial infection among pregnant women (7, 18). As many as 90% of UTIs are caused by Escherichia coli (5). Hormonal and physiological changes in the urinary tract, including ureteral dilatation and changes in bladder volume and tone, may promote infection in pregnant women (18). Interestingly, the incidence of UTI during pregnancy is higher among women who have had childhood infections (13). Furthermore, it has been observed that pregnant women have a propensity to develop recurrent UTIs (18).Overall, UTI can be dangerous for both the mother and fetus. Complications that can arise include preterm delivery and increased incidence of intrauterine growth restriction. To a lesser degree, preeclampsia, caesarean delivery, anemia, sepsis, and septic shock may also be associated with UTI in these patients (14). Among patients suffering acute pyelonephritis, those who are pregnant are more likely than nonpregnant women to develop renal scars (22).The possession of virulence factors that enable colonization is important in the pathogenesis of uropathogenic E. coli (UPEC). It has been demonstrated that among isolates causing acute pyelonephritis in pregnant women, expression of type 1, P, and Dr fimbriae can vary by gestational age (19). However, little is known about the prevalence of other E. coli virulence-associated factors, including those known to play a role in lon...