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991.
Intravascular papillary endothelial hyperplasia (IPEH) is histopathologically characterized by endothelium-lined papillary structures encircling an acellular fibrin core. The process of IPEH pathogenesis is unclear. The purpose of our study was to identify histopathological and immunohistochemical characteristics of IPEH to better understand the pathogenesis of this disease. After reviewing microscopic and medical records from Kyungpook National University Hospital, we selected 16 cases of IPEH. Masson’s trichrome and immunohistochemical staining as well as hematoxylin-eosin staining for 16 cases of IPH were performed. Immunohistochemical studies included CD31, CD68, mast cell tryptase, hypoxia-inducible factor-1 (HIF-1α), and vascular endothelial growth factor (VEGF). Sections from all our cases showed three distinct histological regions including a papillary portion with hyalinized fibrous or fibroblastic cores, an area containing an unorganized thrombus, and organization area with an ingrowth of endothelial cells, myofibroblasts, and fibroblasts. In the organization area, HIF-1α-positive cells were identified in the loose connective tissue. Endothelial cells forming vascular channels were negative for HIF-1α while VEGF was highly expressed in both interstitial mononuclear and endothelial cells. In the papillary portion, the cellular cores were strongly positive for both HIF-1α and VEGF, but the acellular cores were negative. Our investigation confirmed that IPEH is a reactive lesion that incidentally arises during the organization process of older thrombi. It was also found that HIF-1α and VEGF expression was dependent on the thrombus remodeling stage in cases of IPEH.  相似文献   
992.
Glycogenic hepatopathy (GH) is an uncommon cause of serum transaminase elevation in type I diabetes mellitus (DM). The clinical signs and symptoms of GH are nonspecific, and include abdominal discomfort, mild hepatomegaly, and transaminase elevation. In this report we describe three cases of patients presenting serum transaminase elevation and hepatomegaly with a history of poorly controlled type I DM. All of the cases showed sudden elevation of transaminase to more than 30 times the upper normal range (like in acute hepatitis) followed by sustained fluctuation (like in relapsing hepatitis). However, the patients did not show any symptom or sign of acute hepatitis. We therefore performed a liver biopsy to confirm the cause of liver enzyme elevation, which revealed GH. Clinicians should be aware of GH so as to prevent diagnostic delay and misdiagnosis, and have sufficient insight into GH; this will be aided by the present report of three cases along with a literature review.  相似文献   
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994.
Surveillance of oral epithelial dysplasia results in a number of newly diagnosed cases of oral squamous cell carcinoma (SCC). The clinical stage of oral SCC at diagnosis influences the magnitude of treatment required and the prognosis. We aimed to document the stage, treatment, and outcome of oral SCC that arose in patients who were being monitored for oral epithelial dysplasia in a dedicated multidisciplinary clinic. Those with histologically diagnosed lesions were enrolled on an ethically approved protocol and molecular biomarker study. Details of clinical and pathological TNM, operation, radiotherapy, recurrence, second primary tumour, and prognosis, were recorded in patients whose lesions underwent malignant transformation. Of the 91 patients reviewed (median follow-up 48 months, IQR 18-96), 23 (25%) had malignant transformation. All were presented to the multidisciplinary team with stage 1 disease (cT1N0M0). Of these, 21 were initially treated by wide local excision, 2 required resection of tumour and reconstruction, and 2 required adjuvant radiotherapy. At follow-up 3 had local recurrence, one had regional recurrence, one had metachronous lung cancer, and 5 had second primary oral SCC. There were further diagnoses of oral dysplasia in 5 during follow-up, and it is estimated that 76% of patients will have one or other event in 5 years. Disease-specific survival was 100% and overall survival was 96% (22/23). Median follow-up after diagnosis of oral SCC was 24 months (IQR 11-58). Specialist monitoring of oral epithelial dysplasia by a multidisciplinary team allows oral SCC to be detected at an early stage, and enables largely curative treatment with simple and usually minor surgical intervention. The high incidence of second primary oral SCC in high-risk patients with oral epithelial dysplasia further supports intensive targeted surveillance in this group.  相似文献   
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996.
To identify distinct biological pathways of glucose metabolism, we conducted a systematic evaluation of biochemical changes after an oral glucose tolerance test (OGTT) in a community-based population. Metabolic profiling was performed on 377 nondiabetic Framingham Offspring cohort participants (mean age 57 years, 42% women, BMI 30 kg/m2) before and after OGTT. Changes in metabolite levels were evaluated with paired Student t tests, cluster-based analyses, and multivariable linear regression to examine differences associated with insulin resistance. Of 110 metabolites tested, 91 significantly changed with OGTT (P ≤ 0.0005 for all). Amino acids, β-hydroxybutyrate, and tricarboxylic acid cycle intermediates decreased after OGTT, and glycolysis products increased, consistent with physiological insulin actions. Other pathways affected by OGTT included decreases in serotonin derivatives, urea cycle metabolites, and B vitamins. We also observed an increase in conjugated, and a decrease in unconjugated, bile acids. Changes in β-hydroxybutyrate, isoleucine, lactate, and pyridoxate were blunted in those with insulin resistance. Our findings demonstrate changes in 91 metabolites representing distinct biological pathways that are perturbed in response to an OGTT. We also identify metabolite responses that distinguish individuals with and without insulin resistance. These findings suggest that unique metabolic phenotypes can be unmasked by OGTT in the prediabetic state.Diabetes affects >1 in 10 adults 20 years of age or older in the U.S., and more than one-third of all adults have prediabetes (1). Changes in traditional measures of glucose and insulin metabolism are known to occur years before the diagnosis of diabetes is made (2). Using high-throughput profiling of metabolic status, we have shown that elevations in plasma branched-chain and aromatic amino acids are also able to predict future diabetes in otherwise normoglycemic, healthy adults (3). Similarly, lipid profiling has demonstrated novel perturbations in triacylglycerol distribution that signal future diabetes risk (4). These findings highlight how emerging technologies are able to broaden our perspective on early disease states, potentially lending insights into biological mechanisms that underlie diabetes and metabolic disease. Characterizing early metabolic changes may also lead to the early identification of at-risk individuals and may prompt the initiation of proven preventive strategies (5).The oral glucose tolerance test (OGTT) provides a dynamic view of glucose and insulin physiology and has been widely used for decades to diagnose diabetes (6,7). Therefore, we conducted a systematic evaluation of biochemical changes after OGTT in a community-based population, with the goal of providing a broad view of the metabolic response to a glucose challenge. An important advantage of profiling plasma samples before and after glucose ingestion is that each individual is able to serve as their own biological control. In addition to attenuating noise attributable to interindividual variation, this approach limits confounding effects of diet, medications, and other inputs that impact the human metabolome. We used a liquid chromatography/mass spectrometry (LC/MS)–based platform that allowed highly specific identification of small molecules in a targeted manner. In prior pilot studies, our group has shown that metabolite excursions with OGTT revealed a switch from catabolism to anabolism, largely attributable to insulin actions (8). In the current study, we sought to evaluate perturbations with OGTT in an expanded panel of metabolites and in a more comprehensive population-based sample with a high propensity for the development of diabetes, and to investigate these changes in individuals with and without insulin resistance.  相似文献   
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1000.
This study seeks to improve the mechanical performance of stents by conducting reliability performance testing and finite element method (FEM)‐based simulations for coronary stents. Three commercially available stent designs and our own new design were tested to measure the factors affecting performance, specifically foreshortening, recoil, radial force, and flexibility. The stents used in the present experiments were 3 mm in working diameter and 18 mm of working length. The results of the experiments indicate that the foreshortening of stents A, B, C, and our new design, D, was equivalent to 2.25, 0.67, 0.46, and 0.41%, respectively. The recoil of stents A, B, C, and D was 6.00, 4.35, 3.50, and 4.36%, respectively. Parallel plate radial force measurements were A, 3.72 ± 0.28 N; B, 3.81 ± 0.32 N; C, 4.35 ± 0.18 N; and D, 4.02 ± 0.24 N. Radial forces determined by applying uniform pressure in the circumferential direction were A, 28.749 ± 0.81 N; B, 32.231 ± 1.80 N; C, 34.522 ± 3.06 N; and D, 42.183 ± 2.84 N. The maximum force of crimped stent at 2.2‐mm deflection was 1.01 ± 0.08 N, 0.82 ± 0.08 N, 0.92 ± 0.12 N, and 0.68 ± 0.07 N for each of stents A, B, C and D. The results of this study enabled us to identify several factors to enhance the performance of stents. In comparing these stents, we found that our design, stent D, which was designed by a collaborative team from seven universities, performed better than the commercial stents across all parameter of foreshortening, recoil, radial force, and flexibility.  相似文献   
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