33 research outputs found
Control of paratuberculosis: who, why and how. A review of 48 countries
Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns. In a survey of 48 countries we found paratuberculosis to be very common in livestock. In about half the countries more than 20% of herds and flocks were infected with MAP. Most countries had large ruminant populations (millions), several types of farmed ruminants, multiple husbandry systems and tens of thousands of individual farms, creating challenges for disease control. In addition, numerous species of free-living wildlife were infected. Paratuberculosis was notifiable in most countries, but formal control programs were present in only 22 countries. Generally, these were the more highly developed countries with advanced veterinary services. Of the countries without a formal control program for paratuberculosis, 76% were in South and Central America, Asia and Africa while 20% were in Europe. Control programs were justified most commonly on animal health grounds, but protecting market access and public health were other factors. Prevalence reduction was the major objective in most countries, but Norway and Sweden aimed to eradicate the disease, so surveillance and response were their major objectives. Government funding was involved in about two thirds of countries, but operations tended to be funded by farmers and their organizations and not by government alone. The majority of countries (60%) had voluntary control programs. Generally, programs were supported by incentives for joining, financial compensation and/or penalties for non-participation. Performance indicators, structure, leadership, practices and tools used in control programs are also presented. Securing funding for long-term control activities was a widespread problem. Control programs were reported to be successful in 16 (73%) of the 22 countries. Recommendations are made for future control programs, including a primary goal of establishing an international code for paratuberculosis, leading to universal acknowledgment of the principles and methods of control in relation to endemic and transboundary disease. An holistic approach across all ruminant livestock industries and long-term commitment is required for control of paratuberculosis
Beitraege zu Ergebnissen demografischer Forschung und zur Herausbildung und Entwicklung des Leitungs- und Planungssystems der DDR
SIGLEIAB-32121-DD AT 902 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Volatile emissions from Mycobacterium avium subsp. paratuberculosis mirror bacterial growth and enable distinction of different strains.
Control of paratuberculosis in livestock is hampered by the low sensitivity of established direct and indirect diagnostic methods. Like other bacteria, Mycobacterium avium subsp. paratuberculosis (MAP) emits volatile organic compounds (VOCs). Differences of VOC patterns in breath and feces of infected and not infected animals were described in first pilot experiments but detailed information on potential marker substances is missing. This study was intended to look for characteristic volatile substances in the headspace of cultures of different MAP strains and to find out how the emission of VOCs was affected by density of bacterial growth. One laboratory adapted and four field strains, three of MAP C-type and one MAP S-type were cultivated on Herrold's egg yolk medium in dilutions of 10(-0), 10(-2), 10(-4) and 10(-6). Volatile substances were pre-concentrated from the headspace over the MAP cultures by means of Solid Phase Micro Extraction (SPME), thermally desorbed from the SPME fibers and separated and identified by means of GC-MS. Out of the large number of compounds found in the headspace over MAP cultures, 34 volatile marker substances could be identified as potential biomarkers for growth and metabolic activity. All five MAP strains could clearly be distinguished from blank culture media by means of emission patterns based on these 34 substances. In addition, patterns of volatiles emitted by the reference strain were significantly different from the field strains. Headspace concentrations of 2-ethylfuran, 2-methylfuran, 3-methylfuran, 2-pentylfuran, ethyl acetate, 1-methyl-1-H-pyrrole and dimethyldisulfide varied with density of bacterial growth. Analysis of VOCs emitted from mycobacterial cultures can be used to identify bacterial growth and, in addition, to differentiate between different bacterial strains. VOC emission patterns may be used to approximate bacterial growth density. In a perspective volatile marker substances could be used to diagnose MAP infections in animals and to identify different bacterial strains and origins
Influence of the Surfactant Concentration on Miniemulsion Polymerization for the Preparation of Hybrid Nanoparticles
WOS: 000309919000008The surfactant concentration in miniemulsion polymerization is a very important parameter. At surfactant concentrations lower than a critical value, coalescence of monomer droplets changes their size, whereas concentrations too high lead to the formation of micelles and micellar nucleation in the polymerization step. Inorganic particles dispersed in the monomer phase, with the goal to produce hybrid particles, influence the surfactant concentration needed as shown in this contribution. Values for the ideal surfactant concentration have been determined for different combinations of particles and surfactant. Underlying mechanisms for the required adjustment of surfactant concentration are discussed.German Research FoundationGerman Research Foundation (DFG) [SPP1273, LA1013/-14-1, SCHU 1417/6-1]; federal ministry of education and researchFederal Ministry of Education & Research (BMBF) [13N10296]This work was financially supported by the German Research Foundation within the program SPP1273 (Research grants LA1013/-14-1 and SCHU 1417/6-1). The Drop and Bubble Shape Tensiometer PAT-1 from SINTERFACE Technologies was kindly provided by the JointLab IP3, a joint initiative of KIT and BASF. Financial support by the federal ministry of education and research (project 13N10296) is gratefully acknowledged
Potential and limitations of use of the <em>Mycobacterium avium</em> subsp.<em> paratuberculosis</em> specific antigen L5P and its variants produced by chemical synthesis
National audienceBackground: Unlike other MAC members, Mycobacterium avium subsp. paratuberculosis (MAP) does not produce GPL on the surface of the cell wall but a lipopentapeptide called L5P or ParaLP01. The molecular and genetic characterization of this antigen demonstrated that L5P is specific to MAP. Currently available diagnostic tests are based on the use of whole cell antigens that are mainly not MAP specific and that require a pre-absorption step with antigens of M. phlei. This diagnosis detect animals with a late stage infection but are not sensitive enough to detect early stage infection. We hypothesize that the pre-absorption step prevents detection of informative populations of immunoglobulins, especially in animals with subclinical faecal shedding of MAP that are not detected by the current serology-based diagnostics. The L5P antigen has now been used in various studies to evaluate a MAP specific sero-diagnostic. This synthetic molecule was used as a pure product, not requiring pre-absorption step. However a number of parameters must be assessed including the formulation of L5P and with reference to a panel of well defined serum samples.Objective: To assess the potential of L5P and its hydrosoluble variants for the serological diagnosis of MAP infection using collections of sera from different contexts.Method: In order to find the best compound for use in serology we chemically synthesized L5P and derivatives of L5P including water-soluble variants. These pure compounds were evaluated on collections of extensively characterized sera from infected and non-infected cattle, goats and sheep. In addition, the panels of sera included animals infected with M. bovis and M. avium subsp. hominissuis.Results: ROC analysis showed that L5P and also its water-soluble derivatives are suitable for the development of serological diagnosis. Advantageously, these pure synthetic MAP specific antigens can be produced at low cost. The use of L5P has not been validated in the contexts of ovine paratuberculosis. In the context of infections due to other mycobacteria such as M. bovis or the more closely related species M. avium subsp. hominissuis, the L5P did not cross react and therefore may be a valuable antigen to solve ambiguous results in other tests
Cost-effectiveness of noninvasive telemedical interventional management in patients with heart failure: health economic analysis of the TIM-HF2 trial
10.1007/s00392-021-01980-2Clinical Research in Cardiolog
Chromatograms of selected ion traces (m/z 43 & m/z 81) from the headspace of the reference strain DSM 44133 (dilution of bacteria of 10<sup>-2</sup>; red chromatograms) and blank media (blue chromatograms). Retention times of marker substances are described in table 2.
<p>Chromatograms of selected ion traces (m/z 43 & m/z 81) from the headspace of the reference strain DSM 44133 (dilution of bacteria of 10<sup>-2</sup>; red chromatograms) and blank media (blue chromatograms). Retention times of marker substances are described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0076868#pone-0076868-t002" target="_blank">table 2</a>.</p
Effect of density of bacterial growth on emitted amounts of VOCs.
<div><p><b>1: DSM 44133 (laboratory reference strain), 2: JIII-386 (sheep strain), 3-5: JII-2421, JII-3197, JII-0817 (field strains)</b>. </p>
<p>a) 2-ethylfuran b) 2-methylfuran c) 2-pentylfuran d) ethyl acetate e) dimethyldisulfide f) 1-methyl-1-H-pyrrole.</p></div
Principal component analysis on VOCs emitted from 5 different MAP strains and the blank media. 1: DSM 44133 (laboratory reference strain), 2: JIII-386 (sheep strain), 3-5: JII-2421, JII-3197, JII-0817 (field strains).
<p>Principal component analysis on VOCs emitted from 5 different MAP strains and the blank media. 1: DSM 44133 (laboratory reference strain), 2: JIII-386 (sheep strain), 3-5: JII-2421, JII-3197, JII-0817 (field strains).</p
Heat-map with all selected VOCs from the five different MAP strains as well as from the media a) quantitative data b) normalized data; Cultures: 1=DSM 44133, 2=JIII-386, 3-5=JII-2421, JII-3197, JII-0817.
<p>Heat-map with all selected VOCs from the five different MAP strains as well as from the media a) quantitative data b) normalized data; Cultures: 1=DSM 44133, 2=JIII-386, 3-5=JII-2421, JII-3197, JII-0817.</p