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71.
The objective of this study was to determine the turnover rate of the extravascular pool of granulocytes in different regions of the feline gastrointestinal tract. Leukocyte emigration from the vasculature was prevented over a 48-h period by repeated intravenous injections of a monoclonal antibody (MAb IB4) directed against the leukocyte adhesion glycoprotein complex CD11/CD18. Tissue-associated myeloperoxidase (MPO) activity was used to monitor the total tissue granulocyte pool at 0.5, 12, 24, and 48 h after MAb IB4 administration. The mucosal layer of the duodenum, jejunum, ileum, and colon exhibited different kinetics of granulocyte clearance, with average life-spans (t1/2) ranging between 6.9 (colon) and 10.4 h (duodenum). Granulocyte clearance rates of 0.5 × 106 and 2.4 x 106 cells/h/g tissue were estimated (from measured values oft1/2 and tissue granulocyte pool) for the small bowel and colonie mucosae, respectively. The submucosal layer of the intestine exhibited a biphasic reduction in tissue MPO activity following immunoneutralization of CD11/CD18, with an initialt1/2 0.5 h followed by at1/2 of 36–60 h. The initial rapid decline in tissue MPO suggests that a significant fraction of granulocytes in the submucosa is localized in a readily exchangeable pool (e.g., marginated cells within the vasculature). The results of this study indicate that the average life-span of resident granulocytes varies significantly between different regions of the gastrointestinal tract, with the intestinal mucosa exhibiting at1/2 comparable to that previously reported for circulating feline neutrophils (R 8 h).  相似文献   
72.
73.
BACKGROUND: Coconut (Cocos nucifera) is a monocotyledonous plant of the Arecaceae family. Allergy to coconut is infrequent, with only 5 cases reported so far in the medical literature. OBJECTIVE: To identify coconut allergens in 2 patients allergic to this food. METHODS: We describe 2 patients allergic to coconut: an adult pollen-allergic patient monosensitized to coconut who presented with severe oropharyngeal symptoms and a child with a previous allergy to walnut, not allergic to pollen, who developed anaphylaxis on coconut ingestion. Both patients had positive skin prick test results and serum specific IgE (CAP) to coconut. IgE sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting was performed to identify the allergens involved, and a strong IgE binding band detected in both patients was further analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). Stability to pepsin digestion of the coconut extract and its cross-reactivity with tree nuts were studied. RESULTS: An immunoblot showed an almost identical profile of IgE binding proteins in the coconut extract in both patients who reacted strongly to a band of approximately 29 kDa. The peptide analysis by MALDI-TOF MS of this band obtained the sequence GHGKREDPEKR. The protein with the highest correlation with this peptide was found to be a 7S globulin from Elaeis guineensis, another oil palm species also belonging to the Arecaceae family. The 29-kDa band was digested by pepsin in less than 1 minute. Cross-reactivity among coconut, walnut, and hazelnut was demonstrated by CAP inhibition in patient 2. CONCLUSION: We have identified a 7S storage protein as a novel coconut allergen.  相似文献   
74.
We sought to define the risk associated with papillomas and atypical papillomas in breast core needle biopsy specimens from a series of approximately 8,500 biopsies performed during 8 years. From a total of 62 papillary lesions (including papillomas and atypical papillomas), 40 (65%) had histologic follow-up. Overall, 15 (38%) of 40 patients had ductal carcinoma in situ (12 cases) or invasive carcinoma at excision (3 cases). Eight cases diagnosed as papilloma had benign follow-up. Slides were available for review in 38 cases and reclassified into benign papilloma with florid hyperplasia and no or minimal atypia (18 cases), papilloma with separate foci of atypical ductal hyperplasia (7 cases), and severely atypical papillomas "suspicious" for papillary carcinoma (13 cases). Carcinoma was identified in 0 (0%), 2 (29%), and 12 (92%) cases, respectively. We conclude that while atypical papillary lesions and papillomas with associated atypical ductal hyperplasia in breast core needle biopsy specimens are associated with a risk of carcinoma, lesions diagnosed as papilloma or papilloma with no or minimal atypia are benign and do not need to be excised.  相似文献   
75.
Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients.  相似文献   
76.
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles.  相似文献   
77.
Mouse monoclonal antibodies were raised against recombinant Salmonella typhi 36-kDa porin monomer. Specificities of 16 monoclonal antibodies were analyzed as reactivity patterns in dot immunobinding and Western blot (immunoblot) assays using isolated outer membrane proteins of gram-negative bacteria and cloned purified S. typhi porin monomers and trimers. Four monoclonal antibodies were specific for Salmonella spp.  相似文献   
78.
Outer membrane protein A (OmpA) is a class of bacterial cell wall protein that is immunogenic without adjuvant. As specific immune responses are initiated in the lymph nodes (LN, we analyzed the effect of the OmpA from Klebsiella pneumoniae (KpOmpA) onchemokine/ chemokine receptor expression by APC and on cell migration to the LN. Upon contact with KpOmpA, human immature DC and macrophages acquire CCR7 expression and responsiveness to CCL21. In parallel, CCR1 and CCR5 expression is down-regulated and CXCL8, CCL2, CCL3 and CCL5 production is up-regulated. Mice injected subcutaneously with KpOmpA present a transient inflammatory reaction at the site of injection accompanied by an enlargement of the draining LN with a higher proportion of DC and macrophages. Lastly, when exposed to KpOmpA prior injection, DC but not macrophages migrate to the draining LN. In conclusion, KpOmpA confers a migratory phenotype to DC and triggers their migration to the regional LN. This property contributes to explain how innate cells initiate adaptive immune response upon recognition of conserved bacterial components and also why OmpA is immunogenic in the absence of adjuvant.  相似文献   
79.
This study prospectively evaluated the prevalence and risk factors of tinea unguium and tinea pedis in the general adult population in Madrid, Spain. One thousand subjects were clinically examined, and samples of nails and scales from the interdigital spaces of the feet were taken from those patients presenting with signs or symptoms of onychomycosis and/or tinea pedis, respectively. In addition, a sample from the fourth interdigital space of both feet was collected from all individuals with a piece of sterilized wool carpet. Tinea unguium was defined as a positive direct examination with potassium hydroxide and culture of the etiological agent from subjects with clinically abnormal nails. Patients with positive dermatophyte cultures of foot specimens were considered to have tinea pedis. The prevalence of tinea unguium was 2.8% (4.0% for men and 1.7% for women), and the prevalence of tinea pedis was 2.9% (4.2% for men and 1.7% for women). The etiological agents of tinea unguium were identified as Trichopyton rubrum (82.1%), followed by Trichopyton mentagrophytes var. interdigitale (14.3%) and Trichopyton tonsurans (3.5%). Trichophyton rubrum (44.8%) and Trichophyton mentagrophytes (44.8%), followed by Epidermophyton floccosum (7%) and T. tonsurans (3.4%), were the organisms isolated from patients with tinea pedis. The percentage of subjects who suffered simultaneously from both diseases was 1.1% (1.7% for men and 0.6% for women). In a multivariate logistic regression analysis, age (relative risk [RR], 1.03) and gender (RR, 2.50) were independent risk factors for tinea unguium, while only gender (RR, 2.65) was predictive for the occurrence of tinea pedis. In both analyses, the presence of one of the two conditions was associated with a higher risk for the appearance of the other disease (RR, >25).  相似文献   
80.
The National Committee for Clinical Laboratory Standards recommends the use of lysed horse blood-supplemented Mueller-Hinton broth for determining the quantitative antimicrobial susceptibility of Streptococcus pneumoniae. This procedure may be difficult for laboratories using previously prepared or commercial MIC systems. Therefore, a study was undertaken to determine whether previously prepared microdilution trays containing Mueller-Hinton broth without blood could be used for determining the antimicrobial susceptibility of S. pneumoniae by adding whole defibrinated sheep blood to the bacterial suspension used to inoculate the trays. The presence of alpha-hemolysis was used as an indicator of bacterial growth. One hundred isolates of S. pneumoniae selected to represent a distribution of susceptibility patterns were tested by the National Committee for Clinical Laboratory Standards method and the sheep blood-supplemented-inoculum method. Greater than 94% agreement between the two methods was achieved. The sheep-blood-supplemented-inoculum procedure was highly reproducible and easy to perform and provides an acceptable alternative for determining the MICs for S. pneumoniae for laboratories using previously prepared or commercial microdilution systems.  相似文献   
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