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81.
Endothelium-dependent vasodilation in type II diabetes mellitus   总被引:3,自引:0,他引:3  
Endothelial dysfunction is a major feature of atherosclerosis and it can also serve as an early atherosclerotic marker. Evaluation and assessment of the endothelial function is important to prevent serious atherosclerotic disease especially myocardial infarction, cerebrovascular disease and renal failure. To evaluate endothelial function we measured endothelium-dependent vasodilation (flow-mediated dilatation: %FMD) of the brachial artery with ultrasound. This method is non-invasive and can be repeatable in order to follow patients individually. Progressive atherosclerosis is often observed in diabetic patients who are not hypertensive. To evaluate the impairment of the endothelial function in type 2 diabetic patients, we examined %FMD in them and compared with hypertensive patients without diabetes and control subjects. We found that type 2 diabetic patients had the same endothelial dysfunction as hypertensive patients without diabetes. %FMD in both diabetic patients and hypertensive patients was lower than in control subjects. Moreover, %FMD of type 2 diabetic patients with hypertension was lower than %FMD of type 2 diabetic patients without hypertension. These finding suggests that endothelial dysfunction develops under the conditions of hypertension and hyperglycemia. Evaluating endothelial function with ultrasound is useful for assessment of atherosclerosis in diabetes.  相似文献   
82.
Corneal epithelial lesions distinguish vernal keratoconjunctivitis (VKC) from other ocular allergic diseases. Such lesions result from degradation of the corneal epithelial basement membrane, which comprises mostly type IV collagen and laminin. Matrix metalloproteinase 2 (MMP-2) and MMP-9 catalyze the degradation of these 2 extracellular matrix proteins. The possible role of MMP-2 and MMP-9 in the pathogenesis of corneal lesions associated with VKC was investigated by assaying tear fluid for the presence of these enzymes. Tear fluid was collected from 6 eyes of 6 patients with active VKC, 14 eyes of 14 patients with active allergic conjunctivitis, and 6 eyes of 6 nonallergic healthy volunteers. Gelatin zymography revealed that the tear fluid of healthy volunteers contained inactive proforms of both MMP-2 and MMP-9 but not the active forms of these enzymes. Active forms of MMP-2 or MMP-9 were detected in a minority of patients with allergic conjunctivitis. However, with the exception of one individual for whom active MMP-9 was not detected, tear fluid from all patients with VKC contained both proforms and active forms of MMP-2 and MMP-9. These results implicate MMP-2 and MMP-9 in the pathogenesis of corneal epithelial disorders associated with VKC.  相似文献   
83.
To elucidate the frequency of mutations of the β/A4 amyloid protein precursor (APP) gene in early-onset Alzheimer disease, we designed a mismatched PCR-RFLP that can identify all kinds of missense mutations at codon 717 in addition to the seven kinds of known mutations at exon 17. When we screened mutations at exon 17 utilizing this method and the double missense mutations at exon 16 of the APP gene by PCR-RFLP, no cases revealed mutations of the APP gene among 13 familial and 54 sporadic cases, except one family (OS-1) that had previously been reported and used as a positive control of APP717(Val → Ile). Our results support the hypothesis that mutations in the APP gene are not major causes in early-onset Alzheimer disease.  相似文献   
84.
This study was performed to investigate the mechanism involved in a decrease in the serum glucose of golden hamsters infected with plerocercoids of Spirometra erinacei. The concentration of glucagon, the activity of glucose-6-phosphatase in the liver, and the in vivo incorporation of 2-deoxyd-[1,2-3H]glucose into various organs increased in plerocercoid-infected hamsters compared with controls. Furthermore, the serum from the plerocercoid-infected hamsters enhanced the in vitro incorporation of [U-14C]glucose into adipose tissues, compared with control serum. The serum levels of immunoreactive insulin and somatomedin associated with nonsuppressible insulin-like activity in experimental animals, however, were not significantly different from those in controls. Therefore, we conclude that the decrease in serum glucose associated with plerocercoid infection is not the result of a decrease in gluconeogenesis, but the result of an increased utilization of glucose in the peripheral tissues.  相似文献   
85.
We report on a boy with the blepharophimosis sequence and de novo, apparently balanced reciprocal translocation between 3q23 and 4p15.2 [46, XY,t(3;4)(q23;p15.2)de novo]. Possible assignment of this autosomal dominant disorder is discussed. A 3q23 band is a more preferable gene locus of the blepharophi mosis sequence, based on the comparison of clinical manifestations between 4p- and 3q-syndromes.  相似文献   
86.
Human endometrial stromal cells (ESC) can produce a variety of chemokines, especially after inflammatory stimulation. Interferon-gamma-inducible protein-10 (IP-10) is a potent chemoattractant for lymphocytes, and belongs to the family of non-ELR CXC chemokines. The expression of IP-10 in ESC after stimulation with interferon-gamma (IFN-gamma), interleukin-1 beta (IL-1 beta), tumour necrosis factor-alpha (TNF-alpha), or lipopolysaccharide (LPS) was evaluated using an enzyme-linked immunosorbent assay and Northern blot analysis. A small amount of IP-10 protein was detected in the culture media of unstimulated ESC. The expression of IP-10 mRNA was detected in ESC. IFN-gamma, IL-1 beta, TNF-alpha and LPS significantly stimulated the expression of IP-10 mRNA and protein in ESC. These results suggest that the production of IP-10 by ESC is regulated by inflammatory mediators. The modulation of IP-10 concentrations in the local environment may contribute to the normal and pathological processes of human reproduction by regulating leukocyte trafficking in the endometrium.  相似文献   
87.
To examine the effect of colchicine on ethionine induced fatty liver, adult female rats were starved overnight and then injected i.p. with 1 g kg ethionine at 11th hour of fasting; then a half of the rats were also injected i.p. with 2.5 mg kg colchicine twice at 3 and 6 h after the single administration of ethionine. Similarly, fasted control rats were injected i.p. with vehicle alone at the above times. All of the rats were sacrificed after a 20 h fast, and the hepatocytes in periportal areas were observed ultra-structurally. In addition, total lipids in the liver tissue were extracted and determined biochemically. Although similar significant increases of triglyceride were observed in the liver tissue of all ethionine-injected rats, the hapatocytes in the group treated with both chemicals had fewer cytoplasmic fat globules (CFG) than those in the group treated with ethionine only. On the other hand, the diameters of markedly increased membrane-bound lipid particles (MLP) in the double treated group were distributed mainly in the range 0.2–0.4 μm, compared with those (0.1-0.2 μm) in the other groups. These findings indicate that colchicine inhibits the development of CFG in ethionine injured hapatocytes. Acta Pathol Jpn 39: 281∼288, 1989.  相似文献   
88.
Primrose syndrome is a congenital malformation syndrome characterized by intellectual disability, developmental delay, progressive muscle wasting, and ear lobe calcification. Mutations in the ZBTB20 gene have been established as being accountable for this syndrome. In this study, a novel de novo ZBTB20 mutation, NM_001164342.2:c.1945C>T (p.Leu649Phe), has been identified through whole exome sequencing (WES) in a female patient presenting a typical Primrose phenotype. Because the present patient exhibited recurrent otitis media, detailed immunological examinations were performed in this study and subnormal immunoglobulin levels were firstly identified in a Primrose patient. Anatomical anomaly of the inner ear has never been reported in this patient and WES data did not include any relevant variants causally linked with the immunologic defect. Thus, there is a possibility of a relation between an unclassified immunodeficiency with selective IgG2 deficiency and Primrose syndrome and this may be the reason of recurrent otitis media frequently observed in Primrose patients. Because subnormal levels of IgG2 in this patient might be caused by an unrelated and still uncharacterized genetic cause, further studies are required to prove the causal link between aberrant ZBTB20 function and immunodeficiency.  相似文献   
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