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91.
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The distribution of heat shock proteins (HSP) HSP60, HSP73, HSP72 and HSP25 in the isoosmotic cortex and the hyperosmotic medulla of the rat kidney was investigated using Western blot analysis and immunohistochemistry. HSP73 was homogeneously distributed throughout the whole kidney. The level of HSP60 was high in the renal cortex and low in the medulla. HSP25 and HSP72 were present in large amounts in the medulla. Only low levels of HSP25 and almost undetectable amounts of HSP72 were found in the cortex. HSP25 exists in one nonphosphorylated and several phosphorylated isoforms. Western blot analysis preceded by isoelectric focussing showed that HSP25 predominates in its nonphosphorylated form in the outer medulla but in its phosphorylated form in cortex and inner medulla. Although this intrarenal distribution pattern was not changed during prolonged anaesthesia (thiobutabarbital sodium), a shift from the nonphosphorylated to the phosphorylated isoforms of HSP25 occurred in the medulla. The characteristic intrarenal distribution of the constitutively expressed HSPs (HSP73, HSP60, HSP25) may reflect different states of metabolic activity in the isoosmotic (cortex) and hyperosmotic (medulla) zones of the kidney. The high content of inducible HSP72 in the medulla most likely is a consequence of the osmotic stress imposed upon the cells by the high urea and salt concentrations in the hyperosmotic medullary environment.  相似文献   
93.
Craniofacial dyssynostosis (CFD) is a rare disorder related to premature closure of the lambdoid suture and the posterior part of the sagittal suture. Epilepsy, mental retardation, abnormalities of the corpus callosum, and short stature have been reported. We studied a patient with CFD, hydronephrosis, and partially empty sella turcica; the latter two features are reported for the first time. We discuss the brain anomalies and their neurologic sequelae, which are part of the CFD phenotype.  相似文献   
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A complicated history of isolation between Fueguian and Patagonian groups (originated by the appearance of the Straits of Magellan) as much as differences in population structure and life strategies constitute important factors in the clustering pattern of those groups. The aim of this work was to test several hypotheses about population structure and history of Fueguian‐Patagonians to propose a model that incorporates predictions for future studies. R matrix methods and matrix permutation analyses were performed upon a data matrix of craniofacial measurements of 441 skulls divided into nine samples pertaining to six Patagonian and three Fueguian populations. Association of biological distances with three matrices representing several settlement patterns was tested using matrix permutation tests. Results of R matrix study show that the minimum genetic distance obtained confirms separation between Fueguians and Patagonians. Moreover, an analysis of residual variances from the expected regression line confirms admixture between Andean and Pampean populations and Araucanian groups, consistent with ethnohistorical observations. A model representing a long history of isolation between Fueguian and Patagonians, rather than a model emphasizing differences in life‐strategies, presented the best correlation with the biological distance matrix. Because similar results were already obtained in archaeological, molecular, and morphological studies, a model for the settlement of Tierra del Fuego is proposed. It is summarized by four main hypotheses that can be tested independently by different disciplines in the future. Am. J. Hum. Biol. 14:308–320, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
97.
Circulating levels of cytokines are deeply influenced by aging, and few data about serum chemokines are available. The aim of this study was to evaluate the influence of aging on circulating CXCL10. One hundred forty healthy subjects (70 males and 70 females), 10-79 years of age, underwent fasting plasma glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride, and CXCL8 serum assay. Thyroid hormone testing for thyroid-stimulating hormone (TSH), antithyroglobulin (AbTg), and antithyroperoxidase (AbTPO) autoantibodies and thyroid ultrasonography were performed in all subjects to exclude the presence of clinical or subclinical thyroid disease. Serum CXCL10 levels were assayed in all subjects and found to be increased in 14 of 70 females (20%) and in 4 of 70 males (5.7%) (p = 0.01). In a multiple linear regression model including age, body mass index (BMI), systolic and diastolic blood pressure, glycemia, total cholesterol, HDL, LDL, triglycerides, TSH, AbTPO, AbTg, and CXCL8, only age was significantly related to CXCL10 [C.R. 1.30 (0.28-2.33), p = 0.001]. No relationship was present between CXCL8 serum levels and age, suggesting a specificity of CXCL10 elevation as a function of age. Results of this study, performed in healthy subjects on an age gradient, demonstrate an increase in serum CXCL10 with advancing age overall in females, supporting the hypothesis of enhanced Th1 immune responses in aging.  相似文献   
98.
Chronic hypertension is associated with resistance artery remodelling and mechanical alterations. However, the contribution of elastin has not been thoroughly studied. Our objective was to evaluate the role of elastin in vascular remodelling of mesenteric resistance arteries (MRA) from spontaneously hypertensive rats (SHR). MRA segments from Wistar Kyoto rats (WKY) and SHR were pressurised under passive conditions at a range of physiological pressures with pressure myography. Confocal microscopy was used to determine differences in the quantity and organisation of elastin in intact pressure-fixed arteries. To assess the contribution of elastin to MRA structure and mechanics, myograph-mounted vessels were studied before and after elastase incubation. When compared with WKY, MRA from SHR showed: (1) a smaller lumen, (2) decreased distensibility at low pressures, (3) a leftward shift of the stress-strain relationship, (4) redistribution of elastin within the internal elastic lamina (IEL) leading to smaller fenestrae but no change in fenestrae number or elastin amount. Elastase incubation (1) fragmented the structure of IEL in a concentration-dependent fashion, (2) abolished all the structural and mechanical differences between strains, and (3) decreased distensibility at low pressures. The study shows the overriding role of elastin in determining vascular dimensions and mechanical properties in a resistance artery. In addition, it informs hypertensive remodelling. MRA remodelling and increased stiffness are accompanied by elastin restructuring within the IEL and elastin degradation reverses structural and mechanical alterations of SHR MRA. Differences in elastin organisation are, therefore, a central element in small artery remodelling in hypertension.  相似文献   
99.
This study was designed to examine the relationship between orbicularis muscle tension around the eyes and fluctuations in intraocular pressure (IOP) in normal subjects. Using a biofeedback paradigm, 20 male and female subjects were asked to increase and decrease their EMG activity from the orbicularis muscle while receiving EMG feedback. Subjects received 3 alternating blocks of trials in which they attempted to increase and decrease muscle tension while maintaining the eyes open. A fourth trial consisted of a forceful closure of the eyes during the increase period. IOP was measured every 60 s throughout the entire sequence, and electrodes placed above and below the eye recorded eyeblinks. Results suggest that IOP increases with increases in facial muscle tension in normal subjects, a finding which cannot be accounted for by changes in eyeblink frequency. These results imply that increases in IOP occur during periods of increased muscle tension around the eye and suggest that muscle tension levels should be examined among individuals who have abnormally high IOP levels.  相似文献   
100.
Carbonic anhydrase isoenzyme IX, MN/CA IX, is a recently discovered member of the carbonic anhydrase (CA) gene family with a suggested function in acid-base balance, intercellular communication, and cell proliferation. Increased expression of MN/CA IX has been observed with certain epithelial tumors. We investigated the expression of MN/CA IX in 69 colorectal neoplasms, consisting of 1 juvenile polyp, 8 hyperplastic polyps, 39 adenomatous lesions, 21 carcinomas, and 7 metastases. Tissue sections were immunostained with a monoclonal antibody specific to MN/CA IX. The proliferative activity of the tumor cells was evaluated by Ki-67 antigen immunoreactivity. The hyperplastic polyps showed a weak or moderate reaction for MN/CA IX only in the cryptal epithelium, as did the normal intestinal mucosa. The adenomas showed immunoreactivity mainly in the superficial part of the mucosa, whereas the distribution in the carcinomas and metastases was more diffuse. Comparative immunostaining of serial sections for Ki-67, a well established marker of cell proliferation, confirmed that MN/CA IX is expressed in areas with high proliferative capacity. Our results show abnormal MN/CA IX expression in colorectal neoplasms, suggesting its involvement in their pathogenesis. The co-occurrence of MN/CA IX and Ki-67 in the same tumor cells indicates its potential for use as a marker of increased proliferation in the colorectal mucosa.  相似文献   
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