We hypothesized that pregnancy modulates receptor-mediated responses of the uterine artery (UA) by altering G protein activation or coupling. Relaxation and contraction to NaF (0.5-11.5 mM), acetylcholine (10(-9)-10(-5) M), and bradykinin (10(-12)-3 x 10(-5) M) were measured in isolated UA of pregnant and nonpregnant guinea pigs. Responses were measured in the presence and absence of either cho...

BACKGROUND Toll-like receptors play an important role in the regulation of adaptive immunity. This study aimed to investigate whether Toll-like receptor 4 (TLR4) polymorphisms influence the production and persistence of antibodies after acellular pertussis booster vaccination during adolescence. METHODS Seventy-five subjects received a single dose of diphtheria and tetanus toxoids and acellul...

A cytolytic enterotoxin produced by Aeromonas hydrophila, isolate SSU, has been cloned in our laboratory. This enterotoxin lysed rabbit red blood cells, destroyed Chinese hamster ovary cells, caused fluid secretion in rat ligated ileal loops, inhibited the phagocytic function of mouse phagocytes, and was lethal to mice when injected intravenously. In this study, the effect of this cytolytic ent...

77 Infection by the Gram-negative bacterium Bordetella pertussis can lead to the development of pertussis, also known as whooping cough due to the characteristic sound infected infants make following a severe coughing fit. Infection by B. pertussis is fairly common, but it rarely causes serious complications in adults. However, the infection can be fatal in infants and young children if left un...

The reasons for the higher pertussis incidence among Hispanic infants, compared with among infants of other ethnicities, are unknown. The geometric mean concentration of pertussis toxin-specific immunoglobulin G in serum samples from 220 Hispanic neonates was 8.45 EU/mL, as determined by enzyme-linked immunosorbent assay, and it was significantly lower if mothers were adolescents (4.63 EU/mL; P...

Pertussis, a highly contagious respiratory disease, commonly affects infants and young children and can be fatal, especially in babies less than one year of age. Bordetella pertussis continues to circulate even in populations where a high vaccine coverage of infants and children is achieved. Adults are reservoirs for infections in infants, in whom pertussis may be severe and life-threatening. D...

Aerolysin is a pore-forming toxin that plays a key role in the pathogenesis of Aeromonas hydrophila infections. In this study, we have analyzed the effect of aerolysin on human granulocytes (HL-60 cells). Proaerolysin could bind to these cells, was processed into active aerolysin, and led to membrane depolarization, indicating that granulocytes are potential targets for this toxin. Fura-2 measu...

Pertussis is still occurring in highly vaccinated populations, affecting individuals of all ages. Long-lived Th1 CD4(+) T cells are essential for protective immunity against pertussis. For better understanding of the limited immunological memory to Bordetella pertussis, we used a panel of Pertactin and Pertussis toxin specific peptides to interrogate CD4(+) T cell responses at the epitope level...

Bordetella pertussis is a Gram-negative pathogen causing the human respiratory disease called pertussis or whooping cough. Here we examined the role of the RNA chaperone Hfq in B. pertussis virulence. Hfq mediates interactions between small regulatory RNAs and their mRNA targets and thus plays an important role in posttranscriptional regulation of many cellular processes in bacteria, including ...