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1.
Claudins and occludin are integral constituents of tight junctions and are deregulated in a variety of malignancies. Their role in thyroid carcinogenesis has not yet been elucidated. This study investigates the expression of occludin and claudin-1, -4 and -7 in thyroid neoplasms. Ninety-one thyroid neoplasms (15 follicular adenomas, 15 follicular carcinomas, 26 papillary carcinomas, 16 papillary microcarcinomas, 8 medullary carcinomas, 3 poorly differentiated carcinomas, 8 undifferentiated carcinomas) were immunostained with antibodies against occludin and claudin-1, -4 and -7. Occludin was mainly expressed in the form of intracytoplasmic vesicles, whereas all claudins tested exhibited membranous immunostaining. Thirteen out of 15 follicular adenomas, 10/15 follicular carcinomas, 24/26 papillary carcinomas, 15/16 papillary microcarcinomas, 1/8 medullary carcinomas, 2/3 poorly differentiated carcinomas and 2/8 undifferentiated carcinomas exhibited claudin-1 expression, whereas claudin-4 was expressed in 13/15, 12/15, 23/26, 13/16, 7/8, 2/3 and 2/8 of the tumors, respectively, and claudin-7 expression was found in 67, 33, 73, 69, 25, 0 and 13% of the cases, respectively. Occludin was expressed in 100% follicular adenomas, 80% follicular carcinomas, 96% papillary carcinomas, 50% papillary microcarcinomas, 50% medullary carcinomas, 33% poorly differentiated carcinomas and 88% undifferentiated carcinomas. Occludin expression was reduced in papillary microcarcinomas, medullary carcinomas and poorly differentiated carcinomas. All claudins exhibited reduced expression in undifferentiated carcinomas. Claudin-1 was additionally reduced in medullary carcinomas and claudin-7 in follicular, medullary and poorly differentiated carcinomas. A correlation between loss of claudin-1 expression and worse disease-free survival was noted on univariate analysis. Dedifferentiation of the thyroid carcinomas is accompanied by reduction in claudin-1, -4 and -7 expression. A differential expression of tight junction proteins in the different histologic types of thyroid gland is noted. Additionally, claudin-1 expression may be an important prognostic indicator of recurrence in thyroid carcinomas.  相似文献   
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Clinical Rheumatology - Psoriatic arthritis (PsA) is a chronic inflammatory disease associated with psoriasis. Pulmonary involvement is a rare extra-articular manifestation of the disease...  相似文献   
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Vascular disruption that occurs as a consequence of bone fracture, leads to hypoxia at the site of damage. Hypoxia regulates the expression of a number of genes that can modulate energy conservation, cell survival, tissue regeneration and angiogenesis. In this study we investigated the expression of Angiopoietin‐like 4, an adipocytokine that has additional roles in angiogenesis, at the fracture site. We demonstrate that Angptl4 mRNA expression increased early during fracture healing (day 3) returning close to baseline at day14. In the callus, Angptl4 mRNA was visualized in areas of condensing mesenchymal cells, callus cartilage and was especially high in mineralizing osteoblasts located in areas of new bone formation. In vitro, Angptl4 mRNA expression in osteoblasts increased under hypoxic conditions and in cells treated with the hypoxia mimetic desferrioxamine. Angptl4 levels were strongly induced at day 14 in differentiating MC3T3‐E1 osteoblastic cells. Exogenous ANGPTL4 increased expression of Runx2, Spp1, vegfa, and Alp mRNA in differentiating osteoblasts. We suggest that the distribution of Angptl4 in the callus may be driven by hypoxia and that Angptl4 may play a role in osteoblastic differentiation, and possibly angiogenesis via regulation of VEGF. Further studies could reveal a dual role for Angptl4 in angiogenesis and osteogenesis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1364–1373, 2015.  相似文献   
5.
BACKGROUND: This study investigates the correlation of hepatic progenitor cells (HPC) expression with treatment response in patients with chronic hepatitis C. DESIGN: The study comprised 77 liver biopsies with chronic hepatitis C (HCV). All patients were PCR-HCV (+) and received antiviral therapy with interferon or pegylated interferon alpha-2b and ribavirin. Twenty-nine patients were assigned as responders (group A), 29 as nonresponders (group B) and 19 as relapsers (group C). Ten normal liver biopsies were used as controls. Liver paraffin sections were subjected (a) to immunohistochemistry using antibodies for cytokeratins 19 (CK19) and 7 (CK7), alpha-fetoprotein (AFP), leukocyte common antigen (LCA) and CD34 antigen (b) to in situ hybridization for AFP mRNA and (c) to immunohistochemistry+in situ hybridization. Results were expressed as % of positive cells following morphometric analysis. RESULTS: HPC expression was present in all 87 specimens. In the control biopsies, rare HPC were detected. In the CH cases and according to AFP mRNA expression, the grade for % HPC expression was: group B: 53.2+/-2.6> group C: 48.37+/-1.8> group A: 31.4+/-1.6 (group A vs B P<0.01, group A vs C P<0.01, group B vs C P>0.05. Double stain revealed that HPC coexpressed CK19/AFP mRNA, CK7/AFP mRNa and AFP protein/AFP mRNA. HPC-percentages were directly correlated with total HAI score (P<0.01), fibrosis stage (P<0.01), and transaminase values (P<0.05). CONCLUSIONS: This study demonstrates that in cases of chronic hepatitis C, the significant association of HPC expression with the severity of disease and more specifically with the response to treatment implies that HPC development and proliferation may provide additional prognostic information and predict prognosis in such cases.  相似文献   
6.
Background Experimental and clinical studies have demonstrated the pivotal role of oxidative stress in the promotion of hepatic and intestinal injury in obstructive jaundice. The present study was undertaken to investigate the effect of well known antioxidant treatments on the gut–liver axis oxidative status and function in bile duct-ligated rats. Methods A total of 60 male Wistar rats were randomly divided into six groups of 10 animals each: controls, sham operated, bile duct ligated (BDL), and BDL treated with either N-acetylcysteine (NAC), allopurinol, or α-tocopherol (α-TC). Ten days after treatment, the hepatic and intestinal oxidative status was estimated by measuring lipid peroxidation and a battery of biochemical markers comprising the organ’s thiol redox state (i.e., glutathione, cysteine, protein thiols, oxidized glutathione, nonprotein mixed disulfides, oxidized cysteine derivatives, protein symmetrical disulfides, and protein mixed disulfides). Portal and aortic endotoxin concentrations and alanine aminotransferase (ALT) levels were also determined. Results All antioxidant treatments significantly improved intestinal barrier function and protected from cholestatic liver injury, as evidenced by reduction of the portal and aortic endotoxin concentration and ALT levels, respectively. This effect accompanied their significant antioxidant action in both organs, mediated by a certain influence profile on the thiol redox state by each treatment. Conclusion NAC, allopurinol, and α-TC, exerting a potent combined antioxidant effect on the intestine and liver in experimental obstructive jaundice, significantly prevented intestinal barrier dysfunction and liver injury. The variety of results depending on the antioxidant agent that was administered and the marker of oxidative stress that was estimated, indicates that a battery of biomarkers would be more appropriate in assessing pharmacologic responses to therapeutic interventions.  相似文献   
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BackgroundOvarian follicular cyst producing estradiol is a rare cause of isosexual pseudoprecocious puberty. Intense pigmentation of breast papillae, areolae, and labia minora is also rarely reported in the literature.CaseWe describe a 2½ year old girl presenting with signs of precocious puberty and advanced bone age due to a large follicular cyst. Estradiol and Dehydro-epiandrosterone sulfate (DHEAS) levels were remarkably elevated. Hyperpigmentation was also noted. Salpingoophorectomy resulted in regression of precocity and depigmentation, but DHEAS serum levels remained elevated.Summary and ConclusionHigh levels of circulating estradiol due to an ovarian follicle can induce precocious puberty and pigmentation of the skin which regresses after surgical removal of the cyst. Elevated DHEAS levels may be the initiating event causing the formation of the large follicular cyst.  相似文献   
8.
Quantitative bone scan of the sacroiliac joints has long been an established diagnostic method in cases of chronic low back pain (LBP), though its value has been questioned due to the significant overlap of the numerical values between patients with inflammatory sacroiliitis and healthy controls. In an effort to solve this dissent, 133 young male adults aged 18-36 years were studied. We thus aimed to have a relatively homogenous population sample that would include the age that many sacroiliac diseases appear. Thirty-two of our patients had chronic, inflammatory disease of non-infectious origin, as tested by clinicolaboratory procedures (Group A), 29 had mechanical (non-inflammatory type) LBP (Group B), and 72 had been scintiscanned for reasons irrelevant to spine disease (Group C). The members of each group were also classified in three subgroups (a, b and c) according to age. The protocol of planar static multispot bone scan was applied to all three Groups. Three regions of interest (ROI), two on the sacroiliac joints plus one over the L4 vertebra were drawn and finally a non-dimensional numerical parameter called "lambda" was extracted by the equation lambda=total counts/total pixels of the "hottest" of the two sacroiliac joints area divided by the counts/pixels corresponding to the L4 values (lambda=SI/L4). The statistical analysis showed negative correlation of lambda with age in all three groups (P~0.04 for Group A, P~0.012 for Group B and P~0.05 for Group C). When all Groups were examined regardless of age, lambda appeared significantly different (P<0.0005) between Groups A and C, as well as between Groups A and B (P~0.002) but there was no difference between Groups B and C (P~0.12). When the members of each group were analyzed according to age, the paired difference of lambda stirred with remarkable vagueness along the whole spectrum of statistical significance. Conclusively, lambda seems to decrease with ageing at ages ranging from 18 to 36 years (P相似文献   
9.
A patient with two episodes of acute polyradiculoneuropathy (Guillain-Barré syndrome) that both occurred during exacerbation of chronic hepatitis B and separated by a 2-year asymptomatic interval is described. The possible causative relation between the neuropathy and the chronic hepatitis B is discussed.  相似文献   
10.
Patients with liver cirrhosis are prone to serious complications by almost all systems, leading to high morbidity rates and even death. Although the functional and structural derangement of diverse vital organs developed in the course of advanced liver disease is the result of one entity (cirrhosis) there are various treatment modalities for each system's complications, which are often ineffective. Identification of the link which connects the complications of cirrhosis from diverse systems might lead to a global, simple and more effective treatment approach for patients with cirrhosis. Accumulating evidence from experimental and clinical studies suggests that intestinal barrier dysfunction and subsequent gut-derived endotoxemia represent an important common pathogenetic mechanism in the development of diverse complications of cirrhosis. Intestinal oxidative stress seems to be a pivotal factor of gut barrier dysfunction in cirrhosis through promotion of enterocyte apoptosis, modulation of intestinal tight junctions and impairment of intestinal brush border function. In parallel, oxidative stress plays a fundamental role in the aggravation of liver injury and in the structural and/or functional derangements of diverse organs complicating the course of cirrhosis. Our hypothesis is that antioxidant treatments could prevent in a global way virtually all cirrhosis-related complications acting in two crucial levels in the pathophysiological cascade of events: (a) in a primary level, which is the gut-liver axis by ameliorating gut-derived endotoxemia, through prevention of intestinal oxidative stress and its associated gut barrier dysfunction, concurrently conferring direct antioxidant protection in the liver tissue and (b) in a secondary level, which refers to the diverse organs whose function is affected by liver cirrhosis, by preventing their oxidant-related structural and functional derangements.  相似文献   
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