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Honma K Abraham JL Chiyotani K De Vuyst P Dumortier P Gibbs AR Green FH Hosoda Y Iwai K Williams WJ Kohyama N Ostiguy G Roggli VL Shida H Taguchi O Vallyathan V 《Human pathology》2004,35(12):1515-1523
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers’ pneumoconiosis, silicosis, hematite miners’ pneumoconiosis, welders’ pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders. 相似文献
94.
Characterization of the humoral immune response to Chlamydia outer membrane protein 2 in chlamydial infection 总被引:6,自引:0,他引:6
Portig I Goodall JC Bailey RL Gaston JS 《Clinical and diagnostic laboratory immunology》2003,10(1):103-107
Detection of antibodies to an outer membrane protein 2 (OMP2) by enzyme-linked immunosorbent assay (ELISA) by using either the Chlamydia trachomatis- or the Chlamydia pneumoniae-specific protein was investigated. OMP2 is an immunodominant antigen giving rise to antibody responses in humans infected with different C. trachomatis serovars (A to C and D to K) or with C. pneumoniae, which could be detected by OMP2 ELISA. OMP2 ELISA is not species specific, but antibody titers were usually higher on the homologous protein. The sensitivity of this assay was high but varied according to the "gold standard" applied. Levels of antibody to C. pneumoniae OMP2 as detected by ELISA seem to return to background or near-background values within a shorter period of time compared to antibodies to C. pneumoniae detected by microimmunofluorescence (MIF), making it more likely that positive results in ELISA reflect recent infection. Thus, OMP2 ELISA has distinct advantages over MIF and commercially available ELISAs and might be a useful tool for the serodiagnosis of chlamydial infection. 相似文献
95.
Strain variation among Bordetella pertussis isolates from Québec and Alberta provinces of Canada from 1985 to 1994
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Peppler MS Kuny S Nevesinjac A Rogers C de Moissac YR Knowles K Lorange M De Serres G Talbot J 《Journal of clinical microbiology》2003,41(7):3344-3347
Pulsed-field gel electrophoresis and gene typing were able to differentiate among 3,597 Bordetella pertussis isolates circulating in Alberta and Québec Provinces, Canada, from 1985 to 1994 and distinguish them from the strains used in vaccine production. This study provides a baseline for continued surveillance of prevalent and emerging strains of B. pertussis in Canada. 相似文献
96.
OBJECTIVES: The purposes of this study were to examine possible ethnic and sex differences in plasma ET-1 levels at rest and in response to acute stress and to examine relationships between ET-1 and vasoconstrictive-mediated BP reactivity to stress. METHODS: Two hundred twenty-two adolescents (mean age = 18.5 +/- 2.8 years; 130 [70 males] EAs and 92 [48 males] AAs) completed two stressors (video game, forehead cold). Hemodynamic measures and blood samples were collected at catheter insertion and before and immediately after the two stressors, separated by 20-minute rest periods. RESULTS: AAs and males exhibited higher levels of SBP and DBP and of TPRI and ET-1 at each sampling point compared with EAs and females, respectively (p values <.001). AAs and males exhibited greater increases in SBP, TPRI, and ET-1 in response to each stressor (p values <.05). Intraindividual correlations between ET-1 and hemodynamic parameters revealed that most individuals exhibited a positive association between ET-1, BP, and TPRI. However, some individuals exhibited a negative association between ET-1 and the above-mentioned hemodynamics, suggesting a compensatory vasodilation mechanism. CONCLUSION: The findings demonstrate significant sex and ethnicity differences in stress-induced vasoconstrictive peptide release and support the hypothesis that these differences may be important in explaining the ethnicity and sex differences in the prevalence of cardiovascular disease. 相似文献
97.
Characterization of the Humoral Immune Response to Chlamydia Outer Membrane Protein 2 in Chlamydial Infection
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I. Portig J. C. Goodall R. L. Bailey J. S. H. Gaston 《Clinical and Vaccine Immunology : CVI》2003,10(1):103-107
Detection of antibodies to an outer membrane protein 2 (OMP2) by enzyme-linked immunosorbent assay (ELISA) by using either the Chlamydia trachomatis- or the Chlamydia pneumoniae-specific protein was investigated. OMP2 is an immunodominant antigen giving rise to antibody responses in humans infected with different C. trachomatis serovars (A to C and D to K) or with C. pneumoniae, which could be detected by OMP2 ELISA. OMP2 ELISA is not species specific, but antibody titers were usually higher on the homologous protein. The sensitivity of this assay was high but varied according to the “gold standard” applied. Levels of antibody to C. pneumoniae OMP2 as detected by ELISA seem to return to background or near-background values within a shorter period of time compared to antibodies to C. pneumoniae detected by microimmunofluorescence (MIF), making it more likely that positive results in ELISA reflect recent infection. Thus, OMP2 ELISA has distinct advantages over MIF and commercially available ELISAs and might be a useful tool for the serodiagnosis of chlamydial infection. 相似文献
98.
Six-month multicenter study on invasive infections due to Streptococcus pyogenes and Streptococcus dysgalactiae subsp. equisimilis in Argentina
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Lopardo HA Vidal P Sparo M Jeric P Centron D Facklam RR Paganini H Pagniez NG Lovgren M Beall B 《Journal of clinical microbiology》2005,43(2):802-807
During a 6-month period, 95 invasive infections due to Streptococcus pyogenes and group C or group G Streptococcus dysgalactiae subsp. equisimilis were recorded from 40 centers of 16 cities in Argentina. We describe here epidemiologic data available for 55 and 19 patients, respectively, associated with invasive infections due to S. pyogenes and S. dysgalactiae subsp. equisimilis. The associated isolates and 58 additional pharyngeal isolates were genotyped and subjected to serologic and/or antibiotic susceptibility testing. Group A streptococcal emm type distribution and strain association with toxic shock appeared to differ somewhat from results found within the United States; however, serologic characterization and sof sequence typing suggested that emm types found in both countries are reflective of shared clonal types. 相似文献
99.
Leen Van Langendonck Albrecht L. Claessens Johan Lefevre Martine Thomis Renaat Philippaerts Katrien Delvaux Roeland Lysens Bavo Vanden Eynde Gaston Beunen 《American journal of human biology》2002,14(6):735-742
The association between bone mass, body structure, and body composition was explored in 156 men, 40 years of AGE . Bone mineral density (total body, lumbar spine, left arm, and left leg) was obtained by dual‐energy X‐ray absorptiometry (DXA; Hologic QDR 4500A). Body structure was determined from a battery of anthropometric dimensions with a principal components analysis. Body composition was estimated with DXA. From the 24 anthropometric dimensions, three components were extracted and identified as muscle, fat, and skeletal length. Significant correlations between the muscle component and all BMD measurements (r = 0.28–0.44) were obtained. Except for BMD of the left arm, which correlated significantly, but negatively, with the fat component (r = ?0.16), no significant relations were found between the fat component and BMD. There were significant correlations between lean mass, fat mass, and BMD measurements. The correlations were higher between lean mass and BMD (r = 0.22–0.44) than between fat mass and BMD (r = 0.08–0.24). The multiple regression analysis revealed that except for BMD of the left arm only lean mass or the muscle component, and not fat mass or the fat component, were independent predictors of BMD. It is concluded that the principal anthropometric determinant of BMD in middle‐aged men is lean mass or muscle. Am. J. Hum. Biol. 14:735–742, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
100.
Morvan FO Baroukh B Ledoux D Caruelle JP Barritault D Godeau G Saffar JL 《The American journal of pathology》2004,164(2):739-746
Oral mucositis is a common, treatment-limiting, and costly side effect of cancer treatments whose biological underpinnings remain poorly understood. In this study, mucositis induced in hamsters by 5-fluorouracil (5-FU) was observed after cheek-pouch scarifications, with and without administration of RGTA (RG1503), a polymer engineered to mimic the protective effects of heparan sulfate. RG1503 had no effects on 5-FU-induced decreases in body weight, blood cell counts, or cheek-pouch and jejunum epithelium proliferation rates, suggesting absence of interference with the cytotoxic effects of 5-FU. Extensive mucositis occurred in all of the untreated animals, and consisted of severe damage to cheek pouch tissues (epithelium, underlying connective tissue, and muscle bundles). Only half of the RG1503-treated animals had mucositis, over a mean area 70% smaller than in the untreated animals. Basement membranes were almost completely destroyed in the untreated group but was preserved in the RG1503 group. RG1503 blunted or abolished the following 5-FU-induced effects: increases in matrix metalloproteinase (MMP)-2, MMP-9, and plasmin, and decreases in tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. These data indicate that mucositis lesions are related to massive release of proteolytic enzymes and are improved by RG1503 treatment, this effect being ascribable in part to restoration of the MMP-TIMP balance. RG1503 given with cancer treatment might protect patients from mucositis. 相似文献