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11.
Catry B Haesebrouck F Vliegher SD Feyen B Vanrobaeys M Opsomer G Schwarz S Kruif AD 《Microbial drug resistance (Larchmont, N.Y.)》2005,11(4):387-394
To measure the level of antimicrobial resistance in potential bovine respiratory pathogens at different production types, nasal swabs were collected from 57 calves of 13 dairy herds, 150 calves of 9 beef cattle herds, and 289 calves of 5 high-density veal calf herds and investigated for the presence of Pasteurellaceae. All calves were less than 6 months old. Susceptibilities of the Pasteurella and Mannheimia isolates to eight antimicrobials were determined using an agar dilution method. P. multocida (37.3%) and hemolytic Mannheimia organisms (M. haemolytica sensu lato) (6.3%) were the most frequently detected organisms. The overall prevalence of isolates resistant to at least one antimicrobial from the dairy, beef, and veal calves were 17.6% (6/34), 21.9% (14/64), and 71.9% (64/89), respectively. In isolates obtained on the veal calf herds, acquired resistance to ampicillin, oxytetracycline, potentiated sulfonamides, gentamicin, tilmicosin, and enrofloxacin was frequently present, and 32.6% of these isolates were resistant to more than two of the tested antimicrobials. Resistance to ceftiofur and florfenicol was not detected. A substantial within-herd variability of species diversity and resistance profiles among isolates belonging to the genera Pasteurella and Mannheimia was found among the isolates of the veal calf farms. 相似文献
12.
Tacchini-Cottier F Allenbach C Otten LA Radtke F 《European journal of immunology》2004,34(6):1588-1596
Notch1 proteins are involved in binary cell fate decisions. To determine the role of Notch1 in the differentiation of CD4(+) Th1 versus Th2 cells, we have compared T helper polarization in vitro in naive CD4(+) T cells isolated from mice in which the N1 gene is specifically inactivated in all mature T cells. Following activation, Notch1-deficient CD4(+) T cells transcribed and secreted IFN-gamma under Th1 conditions and IL-4 under Th2 conditions at levels similar to that of control CD4(+) T cells. These results show that Notch1 is dispensable for the development of Th1 and Th2 phenotypes in vitro. The requirement for Notch1 in Th1 differentiation in vivo was analyzed following inoculation of Leishmania major in mice with a T cell-specific inactivation of the Notch1 gene. Following infection, these mice controlled parasite growth at the site of infection and healed their lesions. The mice developed a protective Th1 immune response characterized by high levels of IFN-gamma mRNA and protein and low levels of IL-4 mRNA with no IL-4 protein in their lymph node cells. Taken together, these results indicate that Notch1 is not critically involved in CD4(+) T helper 1 differentiation and in resolution of lesions following infection with L. major. 相似文献
13.
Asher Y. Rosinger Samantha M. Olson Sascha R. Ellington Janice Perez-Padilla Regina M. Simeone Caitlin S. Pedati Betsy A. Schroeder Gilberto A. Santiago Freddy A. Medina Jorge L. Muoz-Jordn Laura E. Adams Romeo R. Galang Miguel Valencia-Prado Sonia Bakkour Candimar Coln Mary Goodwin Dana Meaney-Delman Jennifer S. Read Lyle R. Petersen Denise J. Jamieson Carmen C. Deseda Margaret A. Honein Brenda Rivera-García Carrie K. Shapiro-Mendoza 《Emerging infectious diseases》2021,27(5):1505
We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015–2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens. 相似文献
14.
Niels Ødum Niels Morling Johannes Friis Carsten Heilmann Jens J. Hyldig-Nielsen Bodil K. Jakobsen Freddy Karup Pedersen Per Platz Lars P. Ryder Arne Svejgaard 《Tissue antigens》1986,28(4):245-250
Thirty-six unrelated Danish patients with pauciarticular Juvenile Chronic Arthritis (PJCA) and 120 controls were typed for HLA-DPw1-w6 and the local specificity CDPHEI with bulk-expanded Primed Lymphocyte Typing (PLT) cells. The frequency of HLA-DPw2 was 52.8% in PJCA patients and 16.7% in controls (relative risk, RR = 4.5; P less than 0.001). The antigens HLA-Dw5 and/or Dw8 were present in 50% of the patients and in 21.3% of the controls (RR = 4.2; p less than 10(-3)). DPw2 was not associated (in linkage disequilibrium) with Dw5/w8 in patients or in controls, and the DP and D associations with PJCA were independent of each other. However, the combined presence of DPw2 and Dw5 and/or Dw8 gave a significantly higher risk of PJCA than each antigen alone indicating interaction of DP and DR gene products. PJCA is the first disease definitely found to be associated with a DP antigen. 相似文献
15.
Functional expression of 4-1BB (CD137) in the inflammatory tissue in Crohn's disease 总被引:2,自引:0,他引:2
Maerten P Geboes K De Hertogh G Shen C Cadot P Bullens DM Van Assche G Penninckx F Rutgeerts P Ceuppens JL 《Clinical immunology (Orlando, Fla.)》2004,112(3):239-246
4-1BB ligand (L) expressed on antigen presenting cells (APC) interacts with 4-1BB, expressed on activated T cells and this interaction costimulates T cells to secrete cytokines and to proliferate. We investigated whether 4-1BB/4-1BBL interactions might be involved in the pathogenesis of Crohn's disease (CD). In immunohistochemistry, we found 4-1BB expression on lamina propria (LP) cells in inflamed and to a lesser extend in non-inflamed gut tissue from CD patients. mRNA levels for 4-1BB were also elevated in intestinal CD tissue. In contrast, only few 4-1BB-expressing cells were found in inflamed tissue from ulcerative colitis (UC) patients and almost no positive cells were found in control intestinal tissue. 4-1BB expression was better sustained on in vitro activated lamina propria T cells from CD patients compared to controls. Finally, agonistic anti-4-1BB antibody enhanced interferon-gamma (IFN-gamma) production and proliferation of lamina propria T cells from CD patients. Taken together, our data suggest that 4-1BB/4-1BBL interactions contribute to the persistence of gut inflammation in CD. 相似文献
16.
Consumption of contaminated poultry meat is an important cause of Salmonella infections in humans. Therefore, there is a need for control methods that protect broilers from day-of-hatch until slaughter age against infection with Salmonella. Colonization-inhibition, a concept in which a live Salmonella strain is orally administered to day-old chickens and protects against subsequent challenge, can potentially be used as control method. In this study, the safety and efficacy of a Salmonella Enteritidis ΔhilAssrAfliG strain as a colonization-inhibition strain for protection of broilers against Salmonella Enteritidis was evaluated. After administration of the Salmonella Enteritidis ΔhilAssrAfliG strain to day-old chickens, this strain could not be isolated from the gut, internal organs or faeces after 21 days of age. In addition, administration of this strain to one-day-old broiler chickens decreased faecal shedding and caecal and internal organ colonization of a Salmonella Enteritidis challenge strain administered one day later using a seeder bird model. To our knowledge, this is the first report of an attenuated Salmonella strain for which both the safety and efficacy has been shown in long-term experiments (until slaughter age) in broiler strain can potentially be used as a live colonization-inhibition strain for controlling Salmonella Enteritidis infections in broilers. 相似文献
17.
18.
Bonnie R. Valgaeren Bart Pardon Evy Goossens Stefanie Verherstraeten Sophie Roelandt Leen Timbermont Nicky Van Der Vekens Sabrina Stuyvaert Linde Gille Laura Van Driessche Freddy Haesebrouck Richard Ducatelle Filip Van Immerseel Piet Deprez 《Toxins》2015,7(7):2586-2597
Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, whereas in the test group solid feed was provided. Maternal antibodies for alpha toxin were present in 45% of the veal calves and 66% of the beef calves. In beef calves a fluent transition from maternal to active immunity was observed for alpha toxin, whereas almost no veal calves developed active immunity. Perfringolysin antibodies significantly declined both in veal and beef calves. In the second study all calves were seropositive for alpha toxin throughout the experiment and solid feed intake did not alter the dynamics of alpha and perfringolysin antibodies. In conclusion, the present study showed that veal calves on a traditional milk replacer diet had significantly lower alpha toxin antibodies compared to beef calves in the risk period for enterotoxaemia, whereas no differences were noticed for perfringolysin. 相似文献
19.
Heart failure is a major health problem worldwide and, despite effective therapies, is expected to grow by almost 50 % over the next 15 years. Five-year mortality remains high at 50 % over 5 years. Because of the economic burden and large impact on quality of life, substantial effort has focused on treatments with multiple medical (beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ARB), aldosterone antagonists, and combination of ARB/neprilysin blockers, ivabradine) and device therapies (ICD, CRT) which have been implemented to reduce disease burden and mortality. However, in the past decade only two new medical therapies and no devices have been approved by the US FDA for the treatment of heart failure. This review highlights the preclinical and clinical literature, and the implantation procedure, related to a relatively new therapeutic device for heart failure; cardiac contractility modulation (CCM). CCM delivers a biphasic high-voltage bipolar signal to the RV septum during the absolute refractory period, eliciting an acute increase in global contractility, and chronically producing a sustained improvement in quality of life, exercise tolerance, and heart failure symptoms. The technology is used commercially in Europe with nearly 3000 patients implanted worldwide. Indications include patients with reduced EF and normal or slightly prolonged QRS duration, thus filling an important therapeutic gap among the 2/3 of patients with heart failure who do not meet criteria for CRT. The mechanism by which CCM provides benefit can be seen at the cellular level where improved calcium handling (phosphorylation of phospholamban, upregulation of SERCA-2A), reversal of the fetal myocyte gene program associated with heart failure, and reverse remodeling are observed. Recent retrospective studies indicate a long-term mortality benefit. A pivotal randomized controlled study is currently being completed in the USA. CCM appears to be an effective, safe technology for the treatment of heart failure with reduced ejection fraction. 相似文献
20.
Tumor necrosis factor (TNF) inhibitors are widely used biologics for the treatment of several chronic inflammatory diseases. The launch of anti-TNF biosimilars has introduced the possibility of non-medical switching between originator biologics and their biosimilars. However, the potential clinical and patient-reported consequences of non-medical switching remain largely unknown, as much of the evidence comes from poorly or uncontrolled real-world evidence (RWE) studies that often have an element of bias and nonstandardized outcome measures. To appropriately evaluate the safety, efficacy, and immunogenicity of non-medical switching from an originator to its biosimilar, we propose that seven key study design elements should be considered when assessing the existing evidence: studies should be (1) randomized and double-blind, (2) adequately controlled, and (3) adequately powered; include (4) multiple switching, (5) an assessment of immunogenicity, and (6) adequate follow-up duration; and (7) report individual patient-level outcomes. This systematic review assessed the robustness and consistency of the current non-medical switching evidence, with a focus on TNF inhibitors. A comprehensive literature search (January 2012–February 2018) identified 98 publications corresponding to 91 studies (17 randomized controlled trials and 74 RWE studies) describing non-medical switching from a TNF inhibitor originator to its biosimilar. When assessing the totality of this evidence, none of the non-medical switching studies conducted to date were found to use all seven of the key design elements, and the absence of these elements dilutes the robustness of the data. Furthermore, discontinuation rates varied widely among studies (0–87%), suggesting heterogeneity and inconclusiveness of the current efficacy, safety, and immunogenicity evidence, particularly at an individual patient level. Therefore, patients should not be indiscriminately switched from an originator TNF inhibitor to its biosimilar for non-medical reasons. Switching decisions should remain between the treating physicians and their patients and be made on a case-by-case basis, relying upon robust scientific evidence.Funding: AbbVie.Plain Language Summary: Plain language summary available for this article. 相似文献