Age dependent breath methane in the German population

Methane which can sometimes be found in exhaled breath of humans is known to reflect in situ intestinal methanogenic activity. In recent years, several factors have been studied in order to understand their relevance to methane production in the intestinal tract. However, the relationship between age and methane producing status has hitherto not been sufficiently investigated. In the present study we evaluated the relationship between age and percentage of breath methane producers in the German population in 428 subjects with ages ranging from 4 to 95 years. When subjects were divided into age groups of 15 years, an increase in the percentage of breath methane producers with age was observed. The near linear increase (R-2 = 0.977) from 5% for children (1-15 years) to 57% for the elderly (> 75 years) may indicate a continuous development in the human gut methanogenic flora throughout lifetime. However, when subjects were compared on 5 year age intervals, an interruption in the percentage of methane producers in the sixth and seventh decade was noted. We further revealed an age dependence on the ratio of female to male producers. This is shown by a dominance in female breath methane producers during the first half of life which afterwards is replaced by a dominance in male breath methane producers with an approximately linear decrease in the ratio between 20 and 65 years (R-2 = 0.926). These observations might suggest a relationship between methanogenic activity and hormonal factors. Using our data, we predict that the percentage of breath CH4 producers within the German population will increase from its current value of 30% (2013) to 35% by 2050. (C) 2014 Elsevier B.V. All rights reserved

Mikrobestimmung von Lipoproteinlipiden im Serum

Peer Reviewe

Fünf Jahre Empfehlungen der Kommission für Krankenhaushygiene zur Aufbereitung flexibler Endoskope

In einem Rückblick wird auf die nationale und internationale Aufnahme der Empfehlungen der Kommission für Krankenhaushygiene und Infektionsprävention beim Robert Koch-Institut (kurz RKI-Empfehlungen) zur Aufbereitung flexibler Endoskope eingegangen. Die Empfehlungen werden hinsichtlich ihrer Aktualität zu fortbestehenden Problemen wie der Inaktivierung von Prionen und zu neuen Erkrankungen bzw. neuen Erregern wie SARS, aviäre Influenza und C. difficile mit binärem Toxin betrachtet. Es wird auf neue Wirkstoffe und neue Verfahren zur Desinfektion flexibler Endoskope eingegangen. Die RKI-Empfehlungen zur Endo skopaufbereitung werden mit der 2003 publizierten Multi-Society-Guideline amerikanischer endoskopisch ausgerichteter, gastroenterologischer und hygienisch ausgerichteter Fachgesellschaften verglichen. Unterschiede bei den Empfehlungen zur Qualität des nach der Desinfektion zur Schlussspülung zu verwendenden Wassers und bei den mikrobiologischen Kontrollen zur Überprüfung der Endoskopaufbereitung werden besonders herausgearbeitet. Auf in den RKI-Empfehlungen bisher nicht berücksichtigte Aspekte wie Dauer der Lagerung aufbereiteter Endoskope und Infektionsrisiko durch Endo-Washer wird eingegangen.In a short review the national and international reception of the German guidelines for reprocessing flexible endoscopes is presented. The recommendations of the guidelines are discussed in view of recent knowledge on old problems such as prion inactivation and new infectious diseases and new microorganisms such as SARS, avian influenza and C. difficile. New disinfectants and new methods for endoscope disinfection are mentioned, the importance of careful cleaning is underlined. The German guidelines of the Robert Koch Institute and the US Multi-Society guidelines, published in 2003, are compared. The discrepancies concerning recommendations for water quality for final rinsing and need of microbiological controls of endoscope reprocessing are stressed. Aspects not mentioned in the German guidelines, e.g. duration of storage after reprocessing and risk of infection transmission by the endo-washer, are discussed

Semantic and Syntactic Approaches to Simulation Relations

Simulation relations are tools for establishing the correctness of data refinement steps. In the simply-typed lambda calculus, logical relations are the standard choice for simulation relations, but they su#er from certain shortcomings; these are resolved by use of the weaker notion of pre-logical relations instead. Developed from a syntactic setting, abstraction barrier-observing simulation relations serve the same purpose, and also handle polymorphic operations. Meanwhile, second-order prelogical relations directly generalise pre-logical relations to polymorphic lambda calculus (System F). We compile the main refinement-pertinent results of these various notions of simulation relation, and try to raise some issues for aiding their comparison and reconciliation