Assuntos
Saúde Ambiental , Isótopos , Editoração/história , Alemanha , História do Século XX , História do Século XXIRESUMO
OBJECTIVE: Helicobacter pylori (H.p.) infections play a very important role in the development of ulcerations and malignancies of the gastrointestinal tract. It is assumed that the primary infection occurs during childhood, depending on numerous environmental factors among them hygiene and social status. Our aim was to determine whether treatment with antibiotics affects the persistence of H.p. infection. METHODS: In 2006, we conducted an epidemiological study among all grade 8 students in the city of Leipzig (mean age 14.6 years). To determine the prevalence of H.p. infection, a voluntary H.p. test (13C-urea breath test) was performed in all participants. RESULTS: The H.p. prevalence was 6.3% (N = 1,598). A significant difference was found between those students who had been treated with an antibiotic at least once prior to the test and those who had never received any antibiotics (4.0% and 11.1%, respectively, p < 0.001). H.p. prevalence decreased with increasing numbers of antibiotic treatments. CONCLUSION: In adolescence, treatment with "non-H.p. specific" antibiotics appears to significantly affect H.p. prevalence. Moreover, the actual persistence of H.p. in "chronic persistent" H.p. infections appears to fluctuate at least in younger years. Thus, any "non-H.p. specific" antibiotic treatment should be considered in the diagnosis and treatment of H.p. infections and should be taken into account as an important confounder in future epidemiological studies.
Assuntos
Antibacterianos/uso terapêutico , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Adolescente , Antibacterianos/administração & dosagem , Testes Respiratórios/métodos , Emigrantes e Imigrantes/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/efeitos dos fármacos , Humanos , Modelos Logísticos , Masculino , Prevalência , Fatores Socioeconômicos , Inquéritos e Questionários , Ureia/análiseRESUMO
BACKGROUND: Until the beginning of this decade the assumption was that the Helicobacter pylori prevalence increases with the age of the population under consideration. More and more epidemiological studies have been suggestive of constancy in Helicobacter pylori prevalence, but to date there has been no long-term follow-up study in a large group of children confirming this hypothesis. METHODS: Following up our study of H. pylori among school starters and 2nd graders in 1998 and 2000, we conducted a third phase of this study in 2006 using the [13C]-Urea Breath Test and a detailed parent-completed epidemiological questionnaire to evaluate the development of prevalence among the overall population of 8th graders in the city of Leipzig (n = 1,905), and especially of the subgroup of participants who took part in all three study phases (n = 751). RESULTS: The overall H. pylori prevalence was 6.5% and had not significantly changed since 1998 and 2000 (6.1%, 5.7% respectively). However, we noticed a significant lower prevalence in the subgroup that participated in all study phases (2.7%). Moreover, we observed a dependence of prevalence on distribution of sociodemographic risk factors such as foreign nationality of at least one parent, birth outside of Germany, low parental education and unemployment, and > or = 2 older siblings. CONCLUSION: The variability in prevalence is most likely a result of unequal sociodemographic family backgrounds.
Assuntos
Infecções por Helicobacter/epidemiologia , Helicobacter pylori , Adolescente , Fatores Etários , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Masculino , Prevalência , Fatores SocioeconômicosRESUMO
Isotope effects are differences in the properties of the isotopes of an element resulting in different reaction rates of a corresponding compound, in equilibrium constants and in the spectra. Shortly after the discovery of stable isotopes of hydrogen, oxygen, and carbon, Jacob Bigeleisen formulated a theory of isotope effects and calculated possible maximum values. Large isotope effects of (2)H (deuterium) against (1)H (protium) were seen to possibly influence interpretations of reaction mechanisms if corresponding labelling is used. Much work was invested to ensure the safety of deuterium use in men in spite of the large isotope effect. On the other hand, large deuterium isotope effects gave rise to several practical applications. Examples are the enhancement of the stability of some technical products against oxidative and against hydrolytic degradation (oils, pharmaceuticals) as well as alterations of the detoxification metabolism of pharmaceuticals in vivo.