Home About us Contact
|
Home About us Contact | ||
|
|
||
Infected Population (infected + population)
Selected AbstractsEffect of Ligula intestinalis on the reproductive capacity of Rastrineobola argentea in Lake VictoriaJOURNAL OF FISH BIOLOGY, Issue 9 2008I. G. Cowx This study examined the potential effect of the cestode Ligula intestinalis on the reproduction of the indigenous cyprinid Rastrineobola argentea in Lake Victoria. Ligula intestinalis had a marked effect on the breeding cycle of R. argentea. The proportion of the infected population in advanced stages of maturation prior to spawning was considerably reduced compared with uninfected fish. Infection by L. intestinalis significantly reduced the fecundity of individual fish, particularly in the 45,60 mm size range; the component of the population that makes the greatest contribution to reproductive output. The reduction in reproductive output of the R. argentea population could potentially affect replenishment of stocks in this important fishery. [source] Schistosomiasis and liver fibrosisPARASITE IMMUNOLOGY, Issue 11 2009Z. A. ANDRADE Summary Schistosoma mansoni infection invariably results in liver fibrosis of the host. This fibrosis may be represented by small focal areas of chronic inflammation and excess extracellular matrix deposited in periovular granulomas, distributed in variable numbers at the periphery of the portal vein system. This is the outcome of 90% of the infected population in endemic areas. Conversely, a minority of infected individuals develop extensive disease with numerous granulomas along the entire extension of the portal spaces. This latter situation is mainly dependent on special hemodynamic changes created by a heavy worm load, with the subsequent production of numerous eggs and represents a severe form of a peculiar chronic hepatopathy. Thus, host,parasite interactions in schistosomiasis help us to understand a number of important features of liver fibrosis: its initiation and regulation, the significance of accompanying vascular changes, the dynamics of fibrosis formation and regression with antiparasitic treatment; host genetic and immunological contributions, and the pathophysiology of portal hypertension. [source] Retrovirus-mediated transfer of the herpes simplex virus thymidine kinase and enhanced green fluorescence protein genes in primary T lymphocytesBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2000Sabrina Di Florio The EGFP-tk retroviral vector, encoding enhanced green fluorescent protein (EGFP) and the herpes simplex virus thymidine kinase (HSV-tk) packaged in a Phoenix amphotropic cell line, was used to transduce healthy donor T lymphocytes. Infection yielded a mean of 41·8 ± 9·3% SD (range 31·1,48·4%) EGFP-positive cells and a mean of 92 ± 2% SD (range 90,94%) after cell sorting. EGFP expression remained stable for 30 d after infection. The entire gene transfer procedure had no significant effect on lymphocyte subsets and slightly reduced clonogenicity. Ganciclovir (gcv) treatment (1 µg/ml × 10 d) killed all EGFP-positive cells in the transduced and transduced/sorted populations, but had no effect on untransduced controls. Our results show that primary T lymphocytes can be transduced using an EGFP-tk vector that yields a homogeneous infected population without affecting lymphocyte subsets, function and clonogenicity. [source] Food/nutrient intake and risk of atrophic gastritis among the Helicobacter pylori -infected population of northeastern JapanCANCER SCIENCE, Issue 4 2003Ai Montani Although Helicobacter pylori (H. pylori) infection is considered a key risk factor for atrophic gastritis, along with other environmental factors, it is still unclear which factor is involved in the development of atrophic gastritis among H. pylori -infected subjects. In the present cross-sectional study, therefore, we analyzed various dietary factors in relation to the presence of atrophic gastritis among H. pylori -infected subjects who participated in a health check-up program in a town in northeastern Japan. One thousand and seventy-one subjects (362 males and 709 females) who provided both self-administered validated food frequency questionnaires and blood samples were the basis for the study, and all of them were serologically positive for H. pylori immunoglobulin G (IgG) antibody. Among them, 663 (223 males and 440 females) were diagnosed as having atrophic gastritis on the basis of serum pepsinogen levels. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated based on tertile categories of subjects without atrophic gastritis, using logistic regression analysis. Among females, high consumptions of rice (OR=1.6, 95% CI: 1.1,2.3), cod roe (OR=1.5, 95% CI: 1.0,2.2) and cuttlefish (OR=1.5, 95% CI: 1.0,2.3) were associated with a moderately increased risk of atrophic gastritis after adjustment for age (P for trend=0.02 for these items). Among males, high consumptions of rice and miso soup showed a tendency toward an increased risk (P for trend=0.12 and 0.13, respectively). Vegetables and fruits showed no association among either males or females. From these results, it is suggested that the dietary habits of consumers of traditional Japanese foods may play a role in the development of atrophic gastritis after H. pylori infection. (Cancer Sci 2003; 94: 372,377) [source] Occurrence of Bremia lactucae in Natural Populations of Lactuca serriolaJOURNAL OF PHYTOPATHOLOGY, Issue 7 2004I. Petr, elová Abstract In the period 1996,2001 the natural occurrence of Bremia lactucae (lettuce downy mildew) on Asteraceae plants was studied in the Czech Republic. Lactuca serriola (prickly lettuce) is the most common naturally growing host species of B. lactucae. Infection of plants was recorded during the whole vegetation season with the first occurrence in April and last in November. Bremia lactucae was found on host plants in all developmental stages. High percentages of naturally infected populations of L. serriola were recorded. Host plants exhibited broad variation in phenotypic expression of disease symptoms and degree of infection, however, the intensity of infection was rather low in the majority of populations. Geographic distribution of B. lactucae was studied in the two main parts of Czech Republic, central and southern Moravia, and eastern, northern and central Bohemia. Bremia lactucae was recorded in all these areas. Nevertheless, in the warmest parts of the Czech Republic (southern Moravia) only sporadic occurrence of the pathogen was recorded. Bremia lactucae infection on L. serriola and disease severity was judged also in relation to the type of habitat, and the size and density of host plant populations. However, no substantial differences among various habitats were found; only host plants growing in urban areas were frequently free of infection and the degree of infection was very low. Nevertheless, these plants were commonly infected with powdery mildew (Golovinomyces cichoracearum), which is most aggressive pathogen of this type of habitat. [source] | ||||||||||