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71.
Marta Zelazko Magda Carneiro-Sampaio Monica Cornejo De Luigi Diana Garcia De Olarte Oscar Porras Madrigal Renato Berrón Perez Agueda Cabello Marylin Valentin Rostan Ricardo U. Sorensen 《Journal of clinical immunology》1998,18(2):161-166
The Latin American Group for Primary Immunodeficiencies, formed in 1993, presently includes 12 countries. One goal was to study the frequency of primary immunodeficiencies in various regions of the American continent and to enhance knowledge about these diseases among primary-care physicians, as well as allergist–immunologists. Important for this purpose was the development of a registry of primary immunodeficiencies using a uniform questionnaire and computerized database. To date, eight countries have collected information on a total of 1428 patients. Predominantly antibody deficiencies were reported in 58% of patients, followed by cellular and antibody immunodeficiencies associated with other abnormalities in 18%, immunodeficiency syndromes associated with granulocyte dysfunction in 8%, phagocytic disorders in 9%, combined cellular and antibody immunodeficiencies in 5%, and complement deficiencies in 2% of patients. The information gathered from this initial analysis of data will serve to expand the patient database to more areas within participating countries and to new countries and to increase collaboration toward better diagnosis and treatment of these diseases. 相似文献
72.
73.
Tardito D Mori S Racagni G Smeraldi E Zanardi R Perez J 《Journal of affective disorders》2003,76(1-3):249-253
BACKGROUND: Abnormal levels of protein kinase A (PKA) were found in patients with bipolar disorder (BD). Since altered levels are generally accompanied by functional modifications, the purpose of this study was to investigate PKA activity in patients with BD. METHODS: PKA activity was assessed in platelets from 20 drug-free bipolar patients and 19 controls. RESULTS: The cAMP-stimulated PKA activity was significantly increased in bipolar patients compared with controls. LIMITATIONS: This study made use of platelets, which may not fully represent changes occurring in specific brain regions. CONCLUSION: This study adds to the growing evidence suggesting that abnormalities of PKA are associated with BD. 相似文献
74.
75.
Stability of Th1 and Th2 populations 总被引:19,自引:0,他引:19
Perez Victor L.; Lederer James A.; Lichtman Andrew H.; Abbas Abul K. 《International immunology》1995,7(5):869-875
Using an in vitro model for the development of IFN-y-producIng(Th1) and IL-4-produclng (Th1) cells from CD4 T lymphocytesexpressing a transgenlc TCR, we show that IL-12 and IL-4 arethe most potent stimuli for the differentiation of naive T cellsto effector populations. When combinations of cytokines arepresent during T cell priming, the effect of IL-4 Is dominant.Furthermore, differentiated Th1 cells can be converted intoIL-4 producers by exposure to IL-4, but the Th2 phenotype Isnot reversible. The stability of Th2 populations may limit theability to regulate Th2-domlnant responses In pathologic situations. 相似文献
76.
Dr G. Jarry J. -P. Lefebvre S. Debray J. Perez 《Medical & biological engineering & computing》1993,31(2):157-164
Time-resolved tomography is performed in transillumination by using 527 nm picosecond pulses from a passively mode-locked
doubled Nd/glass laser and a streak camera to select photons according to their flight time. This work reports on the increase
in contrast of a time-resolved profile of a 2 mm radius opaque object embedded in a scattering medium, constituted of diluted
milk in a 30 mm thick cell. For spatial analysis, the emerging photons are detected through a 6 mm slit at the outlet face
of the cell. Transmission profiles obtained as a function of time show that the contrast is enhanced for the shortest flight
times, while the ‘shadow’ of the object is no longer detected after about 100 ps. Moreover, improvements in contrast are studied
for different configurations of the model, to analyse separately the role of collimated and scattered photons. It is expected
that such a tomographic method based on time-resolved absorption could be applied to imaging for more complex biological structures
in the red and near-infra-red range. 相似文献
77.
Patterns of basement membrane laminin distribution in nonneoplastic and neoplastic thyroid tissue. 总被引:1,自引:0,他引:1
Laminin, a major basement membrane component, is typically absent or partially lost around the epithelial elements of most invasive carcinomas. To evaluate the distribution of laminin in both primary and metastatic thyroid tumors, we studied 14 benign thyroid lesions (eight adenomas, two Graves' disease, two Hashimoto's thyroiditis, one adenomatous hyperplasia, one nodular goiter), 20 carcinomas (seven papillary, six tall cell variant, four follicular, three Hürthle), and eight metastases (five tall cell variant, three follicular) utilizing a polyclonal antibody against highly purified, nidogen-free laminin. All benign lesions showed positive, linear immunostaining along basement membranes. Partial loss or absence of laminin was seen in the solid areas of all types of thyroid carcinomas examined; well-differentiated papillary and follicular tumors, as well as papillary and follicular areas of more poorly differentiated neoplasms, maintained linear laminin immunostaining in the papillary cores beneath the epithelial cells and around follicles. A similar correlation between laminin deposition and architectural organization was seen in metastatic lesions. Hürthle cell carcinomas had a unique fragmented, pericellular immunostaining pattern around individual tumor cells, suggesting uncontrolled laminin synthesis. Our findings suggest that preservation of laminin production in thyroid tumors reflects their degree of differentiation and that absence of laminin correlates with lack of structural organization rather than reflecting invasive and metastatic potential. 相似文献
78.
Daniel H Berrocal Germán E González Alejandro Fernández Susana Perez Luciana Wilensky Celina Morales Liliana Grinfeld Ricardo J Gelpi 《Cardiovascular pathology》2008,17(5):289-296
BACKGROUND: It is not known whether overexpansion modifies stent recoil, symmetric distribution of struts, and neointimal hyperplasia. OBJECTIVES: The objectives were (a) to evaluate whether stent overexpansion modifies the geometric configuration of the stent in the arterial wall, (b) to determine the relationship between overexpansion and stent recoil, and (c) to evaluate the relationship between the distribution of struts and neointimal hyperplasia. METHODS: Twenty tubular stainless steel 316L stents (3.0 and 3.5 mm in diameter) were implanted at 20 and 10 atm, respectively, in the abdominal aorta of New Zealand rabbits fed a hypercholesterolemic diet (1% cholesterol). Sham operations were also performed in seven animals. Eight weeks after implantation or sham operation, an intravascular ultrasound (IVUS) study was performed to measure stent recoil and aid in stent classification (symmetric or asymmetric) according to strut distribution. The degree of injury and neointimal hyperplasia were also evaluated in hematoxylin-eosin stained sections. RESULTS: The symmetry/asymmetry of stents assessed by IVUS, as well as the neointimal hyperplasia, was similar in both groups. Stent recoil was significantly greater in the 3.0-mm stent (overexpanded) group (0.28+/-0.02 mm), as compared with stent recoil in the 3.5-mm stent group (0.10+/-0.01 mm, P<.05). The neointimal hyperplasia in histological slices, independent of the implant technique, was predominantly in zones with higher strut concentration as compared with zones with fewer struts. CONCLUSIONS: Stent overexpansion enhanced stent recoil and did not modify symmetric and asymmetric strut distribution. Neointimal hyperplasia was not modified by the implant technique. Interestingly, significant hyperplasia was observed in locations with greater strut concentration, independent of overexpansion. 相似文献
79.
Relative frequency of rotavirus subgroups 1 and 2 in Venezuelan children with gastroenteritis as assayed with monoclonal antibodies. 总被引:2,自引:12,他引:2
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L White I Perez M Perez G Urbina H Greenberg A Kapikian J Flores 《Journal of clinical microbiology》1984,19(4):516-520
Monoclonal antibodies recently developed against the 42,000-dalton protein of two rotavirus strains were used in an enzyme-linked immunosorbent assay to determine the subgroup specificity of 252 specimens collected during a 45-month period from Venezuelan children with rotavirus gastroenteritis. Subgroup 2 rotavirus was shed by 85% of the children, whereas only 14% shed subgroup 1 rotavirus (one-half of them in a 3-month period). No differences were found in the occurrence of fever and vomiting between children shedding either rotavirus subgroup, but it appeared that the syndrome tended to last longer in children shedding subgroup 2 rotavirus. The monoclonal subgrouping enzyme-linked immunosorbent assay seemed to be more sensitive than an immune adherence hemagglutination assay, an enzyme-linked immunosorbent assay with polyclonal antibodies, or the electrophoretic analysis of RNA extracted from the virus. Overall, 99% of the specimens could be subgrouped by this assay. 相似文献
80.
Gupta S Heacock M Perez A Davis PB 《American journal of respiratory cell and molecular biology》2005,33(4):363-370
The polymeric immunoglobulin receptor (pIgR) has been proposed as a therapeutic target, but its potential depends on the efficiency of uptake and trafficking of the receptor ligand. Mouse monoclonal antibodies (Mabs) directed against pIgR, selected for strong binding to secretory component (SC) and secretory IgA (sIgA), were tested in a transcytosis assay in 16HBEo--cells (human bronchial epithelial cell line) transfected with human pIgR. Intracellular trafficking was followed by confocal microscopy. Mabs fell into two classes. For two Mabs, transcytosis from basolateral to apical surface is rapid, unidirectional, and little Mab is retained in the cell. For three Mabs, basolateral to apical transcytosis occurs to a significantly lesser extent, reverse transcytosis is permitted, and some of the Mab is retained in the perinuclear region even after 24 h. When tested for their ability to recognize and immunoprecipitate pIgR with systematic truncations and deletions of the five immunoglobulin (Ig)-like domains, all Mabs bound to the fifth Ig-like domain, but three of them also bound to the C-terminal region of pIgR near the plasma membrane. Different binding sites probably account for the different trafficking of these Mabs and may predict differential therapeutic utility. 相似文献