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371.
Hoffman M 《Science (New York, N.Y.)》1992,256(5053):25-27
372.
373.
Kanneboyina Nagaraju Lisa G Rider Chenguang Fan Yi-Wen Chen Megan Mitsak Rashmi Rawat Kathleen Patterson Cecilia Grundtman Frederick W Miller Paul H Plotz Eric Hoffman Ingrid E Lundberg 《Journal of Autoimmune Diseases》2006,3(1):2
Background
While vascular and immune abnormalities are common in juvenile and adult dermatomyositis (DM), the molecular changes that contribute to these abnormalities are not clear. Therefore, we investigated pathways that facilitate new blood vessel formation and dendritic cell migration in dermatomyositis.Methods
Muscle biopsies from subjects with DM (9 children and 6 adults) and non-myositis controls (6 children and 7 adults) were investigated by immunohistochemistry using antibodies that recognize existing (anti-CD146) and newly formed blood vessels (anti-αVβ3) and mature dendritic cells (anti-DC-LAMP). Blood vessel quantification was performed by digitalized image analysis. Additional muscle biopsies from subjects with adult DM and non-myositis controls were used for global gene expression profiling experiments.Results
A significant increase in neovascularization was found in muscle biopsies of DM patients; neovascularization (αVβ3 positive capillaries and vessels per muscle fiber) was much higher in juvenile than in adult DM patients (control vs juvenile DM: Mean ± SE: 0.06 ± 0.01 vs 0.6 ± 0.05; p < 0.0001 and control vs adult DM: Mean ± SE: 0.60 ± 0.1 vs 0.75 ± 0.1; p = 0.051). Gene expression analysis demonstrated that genes that participate not only in angiogenesis but also in leukocyte trafficking and the complement cascade were highly up regulated in DM muscle in comparison to age matched controls. DC-LAMP positive dendritic cells were highly enriched at perivascular inflammatory sites in juvenile and adult DM patients along with molecules that facilitate dendritic cell transmigration and reverse transmigration (CD142 and CD31).Conclusion
These results suggest active neovascularization and endothelial cell activation in both juvenile and adult DM. It is likely that close association of monocytes with endothelial cells initiate rapid dendritic cell maturation and an autoimmune response in DM.374.
Amass SF Arighi M Kinyon JM Hoffman LJ Schneider JL Draper DK 《Journal of the American Veterinary Medical Association》2006,228(9):1391-1396
OBJECTIVE: To determine the effectiveness of using a disinfectant mat filled with a peroxygen compound to prevent mechanical transmission of bacteria via contaminated footwear between the food animal ward and common breezeway of a veterinary teaching hospital. DESIGN: Observational study. SAMPLE POPULATION: Shoe soles of individuals entering and exiting from the ward. PROCEDURES: A mat filled with peroxygen disinfectant was placed at the entrance to the food animal ward, and participants wiped each shoe twice on the mat surface (n = 16) or walked on the mat surface but did not wipe their shoes (17) before entering and exiting from the ward. Swab specimens were collected from the shoe soles of participants before and after mat use and submitted for bacterial culture. RESULTS: For both study days, as participants entered the ward, median number of aerobic bacteria isolated from shoe swab specimens collected prior to use of the disinfectant mat was not significantly different from median number isolated after use of the disinfectant mat. However, as participants exited the ward, median number of aerobic bacteria isolated from shoe swab specimens collected prior to use of the disinfectant mat was significantly higher than median number isolated after use of the disinfectant mat. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that placing a mat filled with a peroxygen disinfectant at the exit from the food animal ward of a veterinary teaching hospital may help reduce mechanical transmission of bacteria on the footwear of individuals leaving the ward. 相似文献
375.
Porcine circovirus type 2 (PCV-2) coinfections in US field cases of postweaning multisystemic wasting syndrome (PMWS). 总被引:18,自引:0,他引:18
F J Pallarés P G Halbur T Opriessnig S D Sorden D Villar B H Janke M J Yaeger D J Larson K J Schwartz K J Yoon L J Hoffman 《Journal of veterinary diagnostic investigation》2002,14(6):515-519
The prevalence of different pathogens detected in combination with porcine circovirus type 2 (PCV-2) was studied retrospectively in field cases of postweaning multisystemic wasting syndrome (PMWS) diagnosed at the Iowa State University Veterinary Diagnostic Laboratory, Ames, Iowa, between January 2000, and September 2001. The presence of PCV-2 antigen in lymphoid tissues and/or lung, demonstrated by immunohistochemistry, together with moderate to severe lymphoid depletion and/or granulomatous lymphadenitis, was used as the criteria for the diagnosis of PMWS. A total of 484 cases fulfilled these criteria. Most of the cases (294/369) of PMWS occurred in pigs between the ages of 8 and 18 weeks, with a peak at 10 weeks of age. Porcine reproductive and respiratory syndrome virus was detected in 51.9% of the cases, Mycoplasma hyopneumoniae in 35.5%, bacterial septicemia in 14.0%, bacterial pneumonia in 7.6%, swine influenza virus in 5.4%, and PCV-2 alone in 1.9%. In cases with bacterial septicemia the most frequently isolated pathogen was Streptococcus suis. In cases with bacterial pneumonia, Pasteurella multocida was the most prevalent. 相似文献