399 research outputs found
Strategy for the identification of micro-organisms producing food and feed products : bacteria producing food enzymes as study case
Recent European regulations require safety assessments of food enzymes (FE) before their commercialization. FE are mainly produced by micro-organisms, whose viable strains nor associated DNA can be present in the final products. Currently, no strategy targeting such impurities exists in enforcement laboratories. Therefore, a generic strategy of first line screening was developed to detect and identify, through PCR amplification and sequencing of the 16S-rRNA gene, the potential presence of FE producing bacteria in FE preparations. First, the specificity was verified using all microbial species reported to produce FE. Second, an in-house database, with 16S reference sequences from bacteria producing FE, was constructed for their fast identification through blast analysis. Third, the sensitivity was assessed on a spiked FE preparation. Finally, the applicability was verified using commercial FE preparations. Using straightforward PCR amplifications, Sanger sequencing and blast analysis, the proposed strategy was demonstrated to be convenient for implementation in enforcement laboratories
SPI-2 of Salmonella Typhimurium is not necessary for long term colonization of pigs
Unravelling the role of Salmonella virulence factors in the porcine host could greatly contribute to the development of control measures such as vaccination. The virulence genes located on the Salmonella Pathogenicity Island 2 (SPI-2) are indispensable for the induction of systemic disease and persistence in BALB/c mice. The role of this pathogenicity island in the pathogenesis of Salmonella Typhimurium infections in pigs is not documented. Therefore, in the present study, the interactions of a porcine field strain of Salmonella Typhimurium and a non-polar isogenic SPI-2 (D-ssrA) deletion mutant were compared in both in vitro and in vivo models. The ssrA mutant strain displayed decreased SPI-2 expression levels in vitro and was attenuated in a mouse model after oral inoculation. No difference was seen in the expression of SPI-1 related virulence genes. Through flowcytometric analysis, the ssrA mutant strain was found to be moderately attenuated in intracellular replication in porcine macrophages in vitro. In an infection experiment, 2 groups of 10 piglets were orally inoculated with the wild type or the ssrA mutant strain. The infection of the animals inoculated with the ssrA mutant strain followed a similar course as the animals infected with the wild type strain. At days 5 and 28 post inoculation, the animals of both groups were infected to the same extent in the gut and gut-associated lymphoid tissue, as well as in the mternal organs. These results suggest that SPI-2 of Salmonella Typhimurium may not contribute to the colonization of pigs to the same extent as it contributes to the colonization of BALB/c mice
Bacteriological evaluation of vaccination against Salmonella Typhimurium with an attenuated vaccine in subclinically infected pig herds
Subclinical infections with Salmonella Typhimurium occur frequently in pigs. They constitute a risk for human salmonellosis and are difficult to control with currently available control measures. Vaccination against Salmonella Typhimurium in pigs can be an effective tool to control Salmonella infections at farm level.
In the present study, the efficacy of an attenuated Salmonella Typhimurium vaccine (Salmoporc®, IDT Biologika) to control Salmonella infections in pigs was evaluated in three subclinically infected pig herds. The effect on Salmonella excretion and the number of pigs positive for Salmonella Typhimurium field and vaccine strains in ileocecal lymph nodes at slaughter were evaluated using five different vaccination strategies: 1. vaccination of sows, 2. vaccination of sows and piglets, 3. vaccination of sows and fattening pigs, 4. vaccination of piglets, 5. vaccination of fattening pigs, which were all compared to a non-vaccinated control group (experimental group 6). Each vaccination strategy was implemented in each farm, during two consecutive production cycles of the same sows.
The prevalence of Salmonella Typhimurium field strain excretion was low; in total, 4% of the fecal and overshoe samples collected in the non-vaccinated control group were Salmonella Typhimurium field strain positive. The excretion of Salmonella Typhimurium field strain did not significantly differ between farms, production cycles and experimental groups. Applying vaccination in either sows and piglets, sows and fattening pigs, or in piglets only, resulted in a significantly reduced number of Salmonella Typhimurium field strain positive lymph nodes of slaughter pigs in the second production cycle, but not in the first production cycle. Vaccination of sows and piglets resulted in the most consistent reduction of Salmonella Typhimurium field strain positive lymph nodes at slaughter. The vaccine strain was detected in the lymph nodes of 13 pigs at slaughter, indicating the possible persistence of the vaccine strain until slaughter.
Because of limitations in the study design, and the variability between farms and production cycles, the results of the current observational study should be extrapolated with care. Nevertheless, the results provide evidence that applying vaccination against Salmonella Typhimurium in sows and piglets (preferred), sows and fattening pigs, and piglets only can support the control of Salmonella Typhimurium infections by decreasing the prevalence of Salmonella Typhimurium field strain positive lymph nodes at slaughter
Interventional Cardiology in Europe 1993
An annual survey on cardiac interventions in Europe is performed by the working group on Coronary Circulation of the European Society of Cardiology with the help of the national societies of cardiology. A questionnaire about cardiac interventions in 1993 was mailed to a representative of the national societies of 35 members of the European Society of Cardiology. The data collection of coronary interventions was delayed by slow backreporting and from 10 of the 35 national members data were missing or grossly incomplete. They were excluded from the analysis. Coronary anglography A total of 756 822 coronary angiograms were reported resulting in an incidence of 1146 ± 1024 per 106 inhabitants, ranging from 24 (Romania) to 3499 (Germany). This represents an increase of 12% compared to 1992. Germany (279 882 cases), France (157 237), the United Kingdom (77 000), Italy (44 934) and Spain (37 591) registered 79% of all the coronary angiograms performed. Percutaneous transluminal coronary angioptasty A total of 183 728 percutaneous transluminal coronary angioplasty cases were reported in 1993, 24% more than in 1992. On average, they accounted for 18 ± 7% (range 8 (Romania) to 35% (Sweden)) of the coronary angiograms. Most of these percutaneous transluminal coronary angioplasties (82%) were confined to a single vessel. In 13% only, percutaneous transluminal coronary angioplasty took place immediately after the diagnostic study. Adjusted per capita, Germany ranks first with 873 percutaneous transluminal coronary angioplasties per 106 inhabitants, followed by France (737), Holland (725), Belgium (713), and Switzerland (665). The European mean of percutaneous transluminal coronary angioplasties per 106 inhabitants was 270 ± 279, representing an increase of 14% compared with 1992. A major in-hospital complication was reported in 3.8% of the patients undergoing percutaneous transluminal coronary angioplasty: 0.6% hospital deaths, 1.5% emergency coronary artery bypass graftings, and 1.7% myocardial infarctions. New devices In 1993 stents were implanted in 6444 patients (3.5% of all percutaneous transluminal coronary angioplasty patients), equally distributed between bail-out situations (53%) and elective procedures. The 14 stent implanting countries showed a mean increase in the incidence of coronary stenting of 53% compared with 1992. Other interventional devices were applied in 7045 cases, i.e. 3.8% of all percutaneous transluminal coronary angioplasty cases. Coronary ultrasound (2194 cases) and coronary angioscopy (380 cases) were performed infrequently. Non-coronary interventions Valvuloplasties were the most frequently performed non-coronary interventions. Six European countries performed more than 300 valvuloplasties each in 1993. Most of them were mitral valvuloplasties in southern countries. Conclusions Although partial backreporting might bias conclusions, several findings of this survey are noteworthy for the participating countries: The number of percutaneous transluminal coronary angioplasties is universally increasing. There is an extremely wide range of coronary angiography and percutaneous transluminal coronary angioplasties performed per population. The most common additional procedure is a stent implantation while other new devices are only rarely applied. Mitral valvuloplasty is the most frequently performed non-coronary intervention. (Eur Heart J 1996; 17: 1318-1328
Mother-to-child transmission of different HIV-1 subtypes among ARV Naïve infected pregnant women in Nigeria
Introduction of HIV-2 and multiple HIV-1 subtypes to Lebanon.
HIV genetic variability, phylogenetic relationships, and transmission dynamics were analyzed in 26 HIV-infected patients from Lebanon. Twenty-five specimens were identified as HIV-1 and one as HIV-2 subtype B. The 25 strains were classified into six env-C2-V3 HIV-1 subtypes: B (n = 10), A (n = 11), C (n = 1), D (n = 1), G (n = 1), and unclassifiable. Potential recombinants combining parts of viral regions from different subtypes Aenv/Dpol/Agag, Genv/Apol, and the unclassifiable-subtype(env)/unclassifiable-subtype(pol)/Agag were found in three patients. Epidemiologic analysis of travel histories and behavioral risks indicated that HIV-1 and HIV-2 subtypes reflected HIV strains prevalent in countries visited by patients or their sex partners. Spread of complex HIV-subtype distribution patterns to regions where HIV is not endemic may be more common than previously thought. Blood screening for both HIV-1 and HIV-2 in Lebanon is recommended to protect the blood supply. HIV subtype data provide information for vaccine development
Long-term follow-up after fractional flow reserve-guided treatment strategy in patients with an isolated proximal left anterior descending coronary artery stenosis.
P04-18. Comparison of HIV neutralization assays for use in vaccine research and clinical trials, phase II: results from the NeutNet working group
Usefulness of quantitative and qualitative angiographic lesion morphology, and clinical characteristics in predicting major adverse cardiac events during and after native coronary balloon angioplasty
Major, adverse cardiac events (death, myocardial infarction, bypass surgery and reintervention) occur in 4 to 7% of all patients undergoing coronary balloon angioplasty. Prospectively collected clinical data, and angiographic quantitative and qualitative lesion morphologic assessment and procedural factors were examined to determine whether the occurrence of these events could be predicted. Of 1,442 patients undergoing balloon angioplasty for native primary coronary disease in 2 European multicenter trials, 69 had major, adverse cardiac procedural or in-hospital complications after ≥1 balloon inflation and were randomly matched with patients who completed an uncomplicated in-hospital course after successful angioplasty. No quantitative angiographic variable was associated with major adverse cardiac events in univariate and multivariate analyses. Univariate analysis showed that major adverse cardiac events were associated with the following preprocedural variables: (1) unstable angina (odds ratio [OR] 3.11; p 45 ° (OR 2.34; p 45 ° (OR 2.87; p 45 ° (OR 2.54; p < 0.006) were independent predictors of major adverse cardiac events
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