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101.
Reza-Albarran AA Gomez-Perez FJ Lopez JC Herrera M Gamboa-Dominguez A Keirns C Aranda A Rull JA 《Endocrine pathology》1999,10(3):251-257
Pigmented nodular cortical hyperplasia, a rare cause of Cushing’s syndrome, is characterized by resistance to inhibition with
dexamethasone and normal sized adrenal glands with multiple, small pigmented nodules. The disorder may be a component of a
syndrome inherited as an autosomal dominant pattern that includes intra- and extracardiac myxomas, lentiginous lesions, blue
nevi, other functional endocrine tumors, and peripheral nerve tumors (Carney’s complex).
We report a patient in whom bilateral myelolipomas were found, in addition to the usual features of this complex. A 29-yr-old
man was admitted to the hospital for Cushing’s syndrome of probably more than 15 yr duration. Physical examination showed
diffuse facial hyperchromatic macules, 0.2–0.5 cm, predominantly around the lips and on the palmar surfaces of the fingers.
Results with dexamethasone suppression nocturnal testing (1 and 8 mg) were compatible with an adrenal adenoma. The computed
tomography (CT) of the sella turcica was normal. Adrenal CT showed a tumor in the left gland with a double component: one
solid and another suggestive of fat, consistent with an angiomyelolipoma. Following 5 wk treatment with ketoconazole, 800
mg per day po, serum cortisol decreased to 5.9 μg/dL, morning and evening, respectively.
Bilateral adrenalectomy was performed. Pathologic examination revealed pigmented nodular cortical hypersplasia and a dominant
myelolipoma in the left adrenal. A microscopic myelolipoma was identified in the right adrenal.
An echocardiogram showed a mass on the posterior wall of the left ventricle which was a myxoma. Study of the patient's family
disclosed two sisters with facial lentigines. Echocardiograms were performed on all available first degree relatives: all
were normal. Nocturnal inhibition with dexamethasone revealed that one of the patient’s sisters with lentigines also had hypercortisolism.
Myelolipoma has been reported in association to Cushing syndrome in humans and experimentally after pituitary extracts in
animals. The relationship between this finding and the Carney’s complex remain elusive. 相似文献
102.
Mónica Sans D Andrew Merriwether Pedro C Hidalgo Nilo Bentancor Tania A Weimer Maria Helena L P Franco Inés Alvarez Brian M Kemp Francisco M Salzano 《American journal of human biology》2006,18(4):513-524
Recent studies of the Uruguayan population revealed different amounts of Amerindian and African genetic contributions. Our previous analysis of Afro-Uruguayans from the capital city of the Department of Cerro Largo showed a high proportion of African genes, and the effects of directional mating involving Amerindian women. In this paper, we extended the analysis to a sample of more than 100 individuals representing a random sample of the population of the whole Department. Based on 18 autosomal markers and one X-linked marker, we estimated 82% European, 8% Amerindian, and 10% African contributions to their ancestry, while from seven mitochondrial DNA site-specific polymorphic markers and sequences of hypervariable segment I, we determined 49% European, 30% Amerindian, and 21% African maternal contributions. Directional matings between Amerindian women and European men were detected, but differences involving Africans were not significant. Data about the specific origins of maternal lineages were also provided, and placed in a historical context. 相似文献
103.
Enrique Hilario Emilia Rodeño Josu Simón Francisco J. Alvarez Salvador F. Aliño 《Virchows Archiv : an international journal of pathology》1992,421(6):485-490
Summary The growth and vascularization patterns of B16 melanoma colonies in the liver and lungs were measured and compared by histological techniques and dye diffusion patterns after injection of the fluorochrome Hoechst 33342. In the liver, the fluorescent pattern of dye diffusion revealed that uninodular tumours measuring up to 146 n in diameter were not functionally vascularized. However, when the nodules fused to give rise to multinodular tumours measuring between 256 and 366 n in diameter, a reticular dye diffusion pattern revealed functional tumour vascularization. In the lungs, subpleural, parenchymal and peritubular (i.e. surrounding blood vessels and airways) tumours were observed. The two former classes were vascularized down to thicknesses and diameters of 49 and 24 m respectively. In contrast, dye diffusion was never seen in peritubular tumour cuffs up to 609 m in thickness. The results indicate differences in vascularization patterns in B16 tumours in the liver and lungs, and differences between tumours growing in different sites within the lungs. If these results are applicable to metastases in these two organs, they indicate potential diffusion-mediated resistance to chemotherapy, and potential hypoxia-mediated resistance to radiotherapy of both metastases and micrometastases. 相似文献
104.
Functional insights on the polarized redistribution of leukocyte integrins and their ligands during leukocyte migration and immune interactions 总被引:4,自引:2,他引:4
Olga Barreiro Hortensia de la Fuente María Mittelbrunn Francisco Sánchez-Madrid 《Immunological reviews》2007,218(1):147-164
Summary: Cell–cell and cell–matrix interactions are of critical importance in immunobiology. Leukocytes make extensive use of a specialized repertoire of receptors to mediate such processes. Among these receptors, integrins are known to be of crucial importance. This review deals with the central role of integrins and their counterreceptors during the establishment of leukocyte–endothelium contacts, interstitial migration, and final encounter with antigen-presenting cells to develop an appropriate immune response. Particularly, we have addressed the molecular events occurring during these sequential processes, leading to the dynamic subcellular redistribution of adhesion receptors and the reorganization of the actin cytoskeleton, which is reflected in changes in cytoarchitecture, including leukocyte polarization, endothelial docking structure formation, or immune synapse organization. The roles of signaling and structural actin cytoskeleton-associated proteins and organized membrane microdomains in the regulation of receptor adhesiveness are also discussed. 相似文献
105.
Campos G Ryder E Diez-Ewald M Rivero F Fernández V Raleigh X Arocha-Piñango CL 《Investigación clínica》2003,44(1):5-19
The aim of this study was to analyse the prevalence of obesity and hyperinsulinemia and their association with lipid profile alterations on apparently healthy individuals from Maracaibo, Venezuela. We evaluated 306 men and 41 women, ages ranging from 33 to 65 years. All subjects underwent cardiovascular evaluation and laboratory examination after 10-12 h fasting, for glycaemia, total cholesterol, TG, VLDL-C, LDL-C and HDL-C as well as insulin. Seventy-four percent of men and 56.1% of women showed obesity (BMI > 25 Kg/m2). Men showed high concentrations of TG (48.3%), total cholesterol (40.2%), VLDL-C (48.3%) and LDL-C (33.9%) and low HDL-C levels (48%). The most frequent alteration on the lipid profile in women was high total cholesterol (46%) and LDL-C (51.2%). Men had significantly higher insulin concentrations than women (p < 0.005). After they were classified as obese or non obese, the obese subjects (men and women) showed higher prevalence of lipid profile alterations and insulin concentrations than non obese. The insulin concentration in obese men correlated with BMI, TG, VLDL-C and HDL and, in women with BMI, TG and VLDL-C. In conclusion, a high percentage of men and women in this study showed obesity and this obesity, specially in men, was strongly associated with lipid profile alterations and high insulin concentrations both well known cardiovascular risk factors. 相似文献
106.
García-Sellés FJ Díaz-Perales A Sánchez-Monge R Alcántara M Lombardero M Barber D Salcedo G Fernández-Rivas M 《International archives of allergy and immunology》2002,128(2):115-122
BACKGROUND: Lipid transfer proteins (LTPs) are major allergens of Rosaceae fruits in the Mediterranean area. IgE-cross-reactivity has been demonstrated in vitro among LTPs from peach, apple, chestnut and Artemisia pollen. The aim of this study was to evaluate the reactivity to LTPs from peach, apple, chestnut and Artemisia pollen by means of skin prick tests (SPTs). METHODS: Forty-seven patients allergic to peach (peach group), 20 patients sensitized to Artemisia pollen with no food allergies (Artemisia group), and 12 control subjects were skin tested with fresh peach, as well as with whole extracts and purified LTPs of peach, apple, chestnut and Artemisia pollen. RESULTS: The rates of positive SPTs for peach, apple, chestnut and Artemisia LTPs were, respectively, 91, 77, 23, and 36% in the peach group, and 30, 5, 15 and 40% in the Artemisia group. No response was observed in the control subjects. SPTs with peach LTP strongly correlated with SPTs conducted with fresh peach. In the peach group, the most frequent pattern of reactivity to LTPs was the combination peach-apple (45%), followed by peach-apple-Artemisia-chestnut (21%). Significant correlations were found between peach and apple LTPs, and between Artemisia and chestnut LTPs. Positive SPTs to chestnut LTP were only observed in patients with positive SPTs to Artemisia LTP. All the patients with positive case histories to chestnut reacted to chestnut LTP. CONCLUSIONS: LTPs are plant panallergens with different patterns of cross-reactivity. They are major allergens of Rosaceae fruits and seem to be involved in allergic reactions to unrelated foodstuffs such as chestnut, probably through sensitization to the cross-reactive Artemisia LTP. Rosaceae LTPs could be useful tools for in vivo diagnosis of Rosaceae fruit allergy. 相似文献
107.
David Hardisson Gema Moreno-Bueno Lydia Sánchez David Sarrió Asunción Suárez Francisco Calero José Palacios 《Modern pathology》2003,16(11):1148-1158
Alterations in the mismatch repair genes (hMLH1 and hMSH2) play an important role in the development of microsatellite instability in sporadic endometrial cancer. Tissue microarray technology allows molecular profiling of tumor samples at the DNA, RNA, and protein levels. We analyzed hMLH1 and hMSH2 expression by immunohistochemistry in a group of atypical endometrial hyperplasias (n = 10), endometrioid endometrial carcinomas (n = 58), and nonendometrioid endometrial carcinomas (n = 27) on tissue microarray. The results were correlated with microsatellite instability status as evaluated by BAT-25 and BAT-26. Overall, 29.4% of lesions showed microsatellite instability. Loss of nuclear hMLH1 and hMSH2 protein expression was seen in 22.3% and 6.5% of cases, respectively. Immunohistochemistry for hMLH1 and hMSH2 showed lack of protein expression in 64% and 16.6% of microsatellite instability-positive endometrial lesions, respectively. Taken together, hMLH1 or hMSH2 protein expression was absent in 18 of 24 microsatellite instability-positive cases (75% sensitivity). A high level of concordance was found between immunohistochemistry for hMLH1 and hMSH2 and microsatellite instability status evaluated by BAT-25 and BAT-26 (kappa value of 0.7). Of the 57 cases found to be microsatellite instability negative, 53 showed normal expression of both proteins (93% specificity). The observed predictive value of absence of expression of hMLH1 for predicting microsatellite instability-positive status was 82%. The predictive value of normal expression of both proteins for predicting microsatellite instability-negative status was 90%. These results are consistent with those previously reported in whole tissue sections. Therefore, immunohistochemical analysis of hMLH1 and hMSH2 expression on tissue microarray provides an accurate technique for screening for tumors with microsatellite instability. Tissue microarrays represent an ideal approach for comparing different diagnostic or predictive markers with one another in consecutive tissue microarray sections. 相似文献
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