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991.
Dietary nucleotides accelerate changes in intestinal lymphocyte maturation in weanling mice 总被引:3,自引:0,他引:3
Manzano M Abadía-Molina AC Olivares EG Gil A Rueda R 《Journal of pediatric gastroenterology and nutrition》2003,37(4):453-461
OBJECTIVE: Nucleotides, the building blocks of nucleic acids, are normal components of the mammalian diet. These molecules have been implicated in biologic processes, such as the stimulation of the immunologic response. Nucleotides have also been considered as conditionally essential nutrients for infant formulas. The authors evaluated the influence of dietary nucleotides on the expression of several surface antigens by different intestinal lymphocyte populations in weanling mice. METHODS: Mice at weaning were fed a semipurified diet with or without 3 g/kg of each of the following nucleotides: adenosine monophosphate, cytosine monophosphate, guanosine monophosphate, and uridine monophosphate. Animals were killed at different times (0, 4, 7, 12, and 18 days) after weaning, and lymphocytes from intestinal Peyer's patches, epithelium, and lamina propria were isolated. The expression of different antigens (CD3, CD4, CD8alpha, CD8beta, TCRalphabeta, TCRgammadelta, CD5, CD22 and CD45R) was analyzed by flow cytometry. RESULTS: The expression of these antigens changed parallel to the maturation of the lymphocytes from Peyer's patches, epithelium, and lamina propria. However, developmental changes of expression for most of the antigens occurred sooner in the animals fed the diet supplemented with nucleotides. The expression of T and B antigens was different in the lymphocyte populations analyzed and also changed according to the diet within each population. In general, nucleotides promoted the expression of B- and T-helper cell antigens. CONCLUSIONS: The authors conclude that dietary nucleotides may affect the process of maturation and differentiation of intestinal lymphocytes, which usually takes place at weaning. 相似文献
992.
Noyola DE Mejía-Elizondo AR Canseco-Lima JM Allende-Carrera R Hernánsez-Salinas AE Ramírez-Zacarías JL 《The Pediatric infectious disease journal》2003,22(1):89-90
The incidence of congenital cytomegalovirus infection in Mexico is unknown. We evaluated the presence of cytomegalovirus infection in 560 newborn infants at a public general hospital. There were five (0.89%) infected newborns. Infants with congenital infection were more likely to be born to primigravid mothers (P = 0.01) and were more often from rural areas (P = 0.058) than were noninfected newborns. 相似文献
993.
Bohórquez CL González-Cámpora R Loscertales MC Escudero AG Mezquita JC 《Pathology, research and practice》2003,199(10):687-690
This report describes the clinical and pathologic findings of a peculiar case of solitary fibrous tumor of the thyroid gland that showed capsular invasion. After four and a half years of follow-up, neither local recurrence nor metastasis has developed. 相似文献
994.
Garfias Y Rojas-Ramos E Jiménez Mdel C Martínez-Cairo S Chávez R Gorocica P Zenteno E Lascurain R 《Immunological investigations》2003,32(1-2):95-104
Atopic disorders are driven by the Th2 cell subset. We have determined the expression of costimulatory molecules and cell surface markers on peripheral CD4+ T cells and antigen presenting cells, in different atopic diseases, and we have also tried to correlate the expression of these markers with the severity of the disease. Cells from patients with atopic and contact dermatitis, mild or severe asthma, and symptomatic and non-symptomatic atopic rhinitis were analyzed by flow cytometry. Our results showed that CD30, CD124, and CD152 expression on CD4+ T cells was significantly higher in atopic dermatitis than in contact dermatitis patients (p < 0.05). It was interesting to observe that the cell surface expression of CD80 in T and B cells from atopic dermatitis patients was not enhanced as opposed to the other atopic diseases we analyzed. Our results suggest that there are differences in the immune mechanisms involved in the different atopic diseases, and that expression of CD30 in CD4+ T cells might be a marker of disease activity in atopic dermatitis. 相似文献
995.
Correlation of c-erbB-2 and S-100 expression with the malignancy grading and anatomical site in oral squamous cell carcinoma 总被引:1,自引:0,他引:1
Albuquerque RL Miguel MC Costa AL Souza LB 《International journal of experimental pathology》2003,84(6):259-265
An immunohistochemical analysis of 32 cases of oral squamous cell carcinoma (eight in the inferior lip, eight in the lateral angle of the tongue, eight in the palate and eight in the mouth floor) was performed to evaluate the expression pattern of c-erbB-2 protein and S-100-positive cells in the lesions. The immunohistochemical expression was correlated with the tumour anatomical site and histological grading of malignancy. A higher frequency of c-erbB-2-positive cases was found in the tongue, even though no correlation could be detected between the protein expression and the tumour histological grading. With respect to the S-100-positive cells, it was observed that a quantitative decrease was present in the cases classified as high-grade tumours when compared to the low ones (P = 0.0007). Thus, c-erbB-2 immunohistochemical expression is correlated with anatomical localization, and the expression of the S-100 Langerhans' cell markers is decreased significantly in high-grade carcinomas. 相似文献
996.
Stelow EB Stanley MW Bardales RH Mallery S Lai R Linzie BM Pambuccian SE 《American journal of clinical pathology》2003,120(3):398-404
All clinically and ultrasonographically suspected examples of intraductal papillary-mucinous neoplasm (IPMN) aspirated during a 17-month period were reviewed and analyzed for follow-up. We identified 18 cases of suspected IPMN in patients 52 to 87 years old. All patients had dilated pancreatic ducts, with 3 showing sonographically apparent intraductal papillary lesions; 5 had adjacent cystic or solid pancreatic masses. Cytologic preparations showed thick, glistening, viscid, abnormal mucus in all cases. Aspirates from 13 lesions (72%) were acellular or sparsely cellular, but entrapped single or loosely cohesive neoplastic cells were identified in 16 cases (89%). Goblet cell morphologic features were common (6/18 [33%]), but papillary clusters and dysplastic changes were infrequent (3 [17%] each). In keeping with current therapeutic thinking, confirmatory histologic follow-up was available for only 4 patients (22%), as most people with lesions clinically, sonographically, and cytologically consistent with IPMN are elderly and often have comorbid conditions. Although endoscopic ultrasound-guided fine-needle aspiration has important limitations, gross and cytologic findings can aid in confirming the suspected diagnosis, and integration of complete clinical, sonographic, and cytologic information may be the best way to reach the most accurate diagnosis possible. 相似文献
997.
The branchio-oculo-facial (BOF) syndrome is a rare autosomal dominant disorder with a peculiar phenotype related to a combination of craniofacial abnormalities. Rare examples presenting with dermal thymic tissue have been described. We are reporting 2 children, 15 and 4 months old, respectively, with BOF syndrome in whom surgical repair/excision of skin cervical lesions showed thymic tissue. In the first patient the thymic tissue was exposed to the surface, without epithelial coverage and contained areas suggestive of all stages of thymus formation. A dermohypodermal nodule of fully developed thymic tissue superficially covered by nonkeratinizing squamous epithelium was found in the second patient. Since pharyngeal pouches are not exposed to the surface during normal embryogenesis and the thymus originates from the third pharyngeal pouch, both examples seem to indicate that in BOF syndrome there is a more complex malformation than simply ectopic thymus tissue. Thymic tissue at the skin appears to be unique for BOF syndrome and in a given case may provide the clue for the accurate diagnosis of the malformation complex. 相似文献
998.
Diffusion imaging may predict reversible brain lesions in eclampsia and severe preeclampsia: initial experience 总被引:4,自引:0,他引:4
Loureiro R Leite CC Kahhale S Freire S Sousa B Cardoso EF Alves EA Borba P Cerri GG Zugaib M 《American journal of obstetrics and gynecology》2003,189(5):1350-1355
OBJECTIVE: The purpose of this study was to validate diffusion-weighted magnetic resonance imaging in the prediction of the evolutive course of brain edema and to establish its pathophysiologic presence in patients with eclampsia/severe preeclampsia. STUDY DESIGN: Seventeen patients with a clinical diagnosis of severe eclampsia/preeclampsia and T2 hyperintense brain lesions on routine magnetic resonance imaging were evaluated at hospital admission and 8 weeks later. RESULTS: Brain edema was reversible in 13 patients and irreversible in 4 patients, as indicated on follow-up magnetic resonance imaging. Sixteen of 17 patients were differentiated accurately into reversible and irreversible groups on the basis of diffusion imaging on hospital admission. Diffusion-weighted magnetic resonance imaging demonstrated a significant increase in water mobility in abnormal regions compared with normal-appearing brains in patients in the reversible group (1.34+/-0.10 mm(2) vs 0.79+/-0.08 mm(2)/s x 10(-3), P<.001). In the irreversible group, restricted water diffusion was present, which was consistent with cytotoxic edema and early brain infarction in 3 of 4 patients. CONCLUSION: Diffusion-weighted magnetic resonance imaging can predict successfully the evolutive course of brain edema in an acute setting in these patients. Our findings indicate that brain edema is vasogenic, although ischemic/cytotoxic edema was observed less commonly. 相似文献
999.
OBJECTIVE: To investigate the attitudes of Argentine parents of children with nonsyndromic oral clefts with respect to prenatal diagnosis, termination of pregnancy, and reproduction and to assess the variables that might influence their responses. DESIGN: One hundred and sixty-five parents of children with oral clefts, ascertained from a craniofacial clinic in the suburbs of Buenos Aires, answered a 151-item semistructured questionnaire. The questionnaire included sections covering sociodemographic information, level of religiousness, characteristics of the child's cleft, parental perception of their child's cleft, pregnancy history, recurrence risk, access to health care, attitudes in regard to abortion, and family environment. RESULTS: Most parents (60%) believe their child's cleft is not a serious condition. None of the respondents would terminate a pregnancy because the ultrasound reveals an oral cleft. Similarly, very few (6.1%) would terminate the pregnancy if there were an early diagnosis of Down syndrome. Half of the respondents believe that abortion should not be an option for any couple expecting a child. CONCLUSIONS: Most respondents do not perceive oral clefts as a severe condition. Parents would not choose to terminate the pregnancy over delivery of such an affected newborn. 相似文献
1000.
Androgen excess is the key element in polycystic ovary syndrome 总被引:3,自引:0,他引:3
Azziz R 《Fertility and sterility》2003,80(2):252-254