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排序方式: 共有1447条查询结果,搜索用时 31 毫秒
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Lomonaco R Ortiz-Lopez C Orsak B Webb A Hardies J Darland C Finch J Gastaldelli A Harrison S Tio F Cusi K 《Hepatology (Baltimore, Md.)》2012,55(5):1389-1397
The role of adipose tissue insulin resistance in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains unclear. To evaluate this, we measured in 207 patients with NAFLD (age = 51 ± 1, body mass index = 34.1 ± 0.3 kg/m(2) ) and 22 controls without NAFLD (no NAFLD) adipose tissue insulin resistance by means of a validated index (Adipo-IR(i) = plasma free fatty acids [FFA] x insulin [FPI] concentration) and as the suppression of plasma FFA during an oral glucose tolerance test and by a low-dose insulin infusion. We also explored the relationship between adipose tissue insulin resistance with metabolic and histological parameters by dividing them based on quartiles of adipose tissue insulin resistance (Adipo-IR(i) quartiles: Q1 = more sensitive; Q4 = more insulin resistant). Hepatic insulin resistance, measured as an index derived from endogenous glucose production x FPI (HIRi), and muscle insulin sensitivity, were assessed during a euglycemic insulin clamp with 3-[(3) H] glucose. Liver fat was measured by magnetic resonance imaging and spectroscopy, and a liver biopsy was performed to assess liver histology. Compared to patients without steatosis, patients with NAFLD were insulin resistant at the level of adipose tissue, liver, and skeletal muscle and had higher plasma aspartate aminotransferase and alanine aminotransferase, triglycerides, and lower high-density lipoprotein cholesterol and adiponectin levels (all P < 0.01). Metabolic parameters, hepatic insulin resistance, and liver fibrosis (but not necroinflammation) deteriorated as quartiles of adipose tissue insulin resistance worsened (all P < 0.01). CONCLUSION: Adipose tissue insulin resistance plays a key role in the development of metabolic and histological abnormalities of obese patients with NAFLD. Treatment strategies targeting adipose tissue insulin resistance (e.g., weight loss and thiazolidinediones) may be of value in this population. 相似文献
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Grinspon RP Ropelato MG Bedecarrás P Loreti N Ballerini MG Gottlieb S Campo SM Rey RA 《Clinical endocrinology》2012,76(5):698-705
Context The biphasic ontogeny of serum gonadotrophins observed in normal children also exists in girls with gonadal dysgenesis, although with higher levels. However, limited data exist in prepubertal boys with anorchia. Objective To investigate whether the existence of testicular tissue is required for gonadotrophin downregulation in boys. Secondarily, we analysed the prevalence of high gonadotrophins and its diagnostic value to assess the presence or absence of testes in childhood. Study design In a retrospective, semi‐longitudinal study, we compared serum gonadotrophin levels in 35 boys with anorchia aged 0–18 years, in 29 bilaterally cryptorchid boys with abdominal testes and in 236 normal boys. Results In anorchid boys, follicle stimulating hormone (FSH) and luteinizing hormone (LH) were abnormally high in the first months after birth, then decreased progressively. LH decreased more readily than FSH and dropped to normal values in up to 70% of anorchid patients before the usual age of pubertal onset, when both gonadotrophins increased again to very high levels. In cryptorchid boys, FSH was elevated in a significantly (P < 0·0001) lower proportion of cases. Below the age of 6 years, FSH below 2 IU/l ruled out anorchia and LH above 5 IU/l confirmed anorchia with high accuracy. Between 6 and 11 years, FSH or LH levels above 5 IU/l were highly specific for the absence of testes. Conclusions The U‐shaped pattern of serum gonadotrophins observed in normal males from birth to puberty was also found in anorchid boys, but with gonadotrophin levels considerably elevated. Serum gonadotrophin levels may normalize in anorchid boys during late childhood only to rise again at puberty. The presence of testicular tissue results in restrain of gonadotrophin secretion in most patients, even if the testes are cryptorchid. 相似文献
66.
Kurtz M Martínez N Capobianco E Higa R Fornes D White V Jawerbaum A 《Molecular and cellular endocrinology》2012,362(1-2):120-127
The fetal lung is affected by maternal diabetes. Nuclear receptor PPARα regulates nitric oxide (NO) overproduction in different tissues. We aimed to determine whether fetal lung PPARα expression is altered by maternal diabetes, and if there are gender-dependent changes in PPARα regulation of NO production in the fetal lung. Fetal lungs from control and diabetic rats were explanted on day 21 of gestation and evaluated for PPARα expression and NO production. Fetuses were injected with the PPARα ligand LTB(4) on days 19, 20 and 21, and the fetal lung explanted on day 21 to evaluate PPARα and the inducible isoform of NO synthase (iNOS). Besides, pregnant rats were fed with olive oil- and safflower oil-supplemented diets, enriched in PPAR ligands, for evaluation of fetal lung NO production and PPARα expression. We found reduced PPARα concentrations only in the lung from male fetuses from the diabetic group when compared to controls, although maternal diabetes led to NO overproduction in both male and female fetal lungs. Fetal activation of PPARα led to changes in lung PPARα expression only in female fetuses, although this treatment increased iNOS expression in both male and female fetuses in the diabetic group. Diets supplemented with olive oil and not with safflower oil led to a reduction in NO production in male and female fetal lungs. In conclusion, there are gender-dependent changes in PPARα expression and signaling in the fetal lung from diabetic rats, although PPARα activation prevents maternal diabetes-induced lung NO overproduction in both male and female fetuses. 相似文献
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Juan Aitken-Saavedra Rafael G. Lund Jaime González Romina Huenchunao Ilia Perez-Vallespir Irene Morales-Bozo 《Acta odontologica Scandinavica》2013,71(8):580-586
Objective: To determine number, species of Candida and Candida resistance to antifungal therapy according to the metabolic control state and the associated salivary changes in patients with type 2 diabetes mellitus (DM2).Materials and methods: Samples of non-stimulated saliva were collected from 52 patients with DM2. Salivary pH was measured and cultured on Sabouraud glucose agar and the values of CFU/ml were calculated. The species were presumptively identified using CHROMagar Candida® plates, and identification was confirmed by polymerase chain reaction (PCR). C. albicans isolates were cultured on SGA tetracycline agar with nystatin and fluconazole diffusion disks to measure susceptibility.Results: Sixty six percent of the yeasts isolated were Candida albicans, followed by C. glabrata (20.7%). In patients with decompensated DM2, there was an inverse association between HbA1c value and salivary pH. At higher levels of salivary acidification, a greater diversity and quantity of yeasts of the genus Candida were observed. With nystatin, higher inhibition was observed at lower pH.Conclusions: The antifungal therapies could be more effective if it consider, qualitative salivary characteristics as pH, that could determine the susceptibility of species of Candida to at least to nystatin, which is the most used antifungal for treatment to oral candidiasis in patients with DM2. 相似文献
69.
Alessandro Buda Cuzzocrea Marco Carlotta Dolci Federica Elisei Romina Baldo Luca Locatelli Rodolfo Milani Cristina Messa 《International journal of surgery case reports》2013,4(10):809-812
INTRODUCTIONOccult endometrial cancer after supracervical hysterectomy is very uncommon. Even if optimal management of those rare cases is still unproven, to guide the need for further therapies, restaging should be recommended in this situation.PRESENTATION OF CASEWe report of a 60-year old woman with occult high risk endometrial cancer after supracervical hysterectomy with morcellation. We describe the feasibility of laparoscopic intraoperative sentinel node identification with cervical stump removing to restage the suspicious early stage high risk endometrial cancer.DISCUSSIONIn high risk endometrial cancer surgical restaging is important, considering that 10–35% of cases can present pelvic nodal metastasis. To reduce the treatment related morbidity maintaining the benefit of surgical staging, with a negative preoperative PET/CT, we performed a laparoscopic SN mapping with cervical stump removing.CONCLUSIONThis report highlight the fact that SN mapping with cervical injection is a feasible and safe technique also without the uterine corpus after supracervical hysterectomy with morcellation. 相似文献
70.
Silvia Sookoian Diego Flichman Romina Scian Cristian Rohr Hernán Dopazo Tomas Fernández Gianotti Julio San Martino Gustavo O Castaño Carlos J Pirola 《The Journal of pathology》2016,240(4):437-449
Non‐alcoholic fatty liver disease (NAFLD) is associated with mitochondrial dysfunction, a decreased liver mitochondrial DNA (mtDNA) content, and impaired energy metabolism. To understand the clinical implications of mtDNA diversity in the biology of NAFLD, we applied deep‐coverage whole sequencing of the liver mitochondrial genomes. We used a multistage study design, including a discovery phase, a phenotype‐oriented study to assess the mutational burden in patients with steatohepatitis at different stages of liver fibrosis, and a replication study to validate findings in loci of interest. We also assessed the potential protein‐level impact of the observed mutations. To determine whether the observed changes are tissue‐specific, we compared the liver and the corresponding peripheral blood entire mitochondrial genomes. The nuclear genes POLG and POLG2 (mitochondrial DNA polymerase‐γ) were also sequenced. We observed that the liver mtDNA of patients with NAFLD harbours complex genomes with a significantly higher mutational (1.28‐fold) rate and degree of heteroplasmy than in controls. The analysis of liver mitochondrial genomes of patients with different degrees of fibrosis revealed that the disease severity is associated with an overall 1.4‐fold increase in mutation rate, including mutations in genes of the oxidative phosphorylation (OXPHOS) chain. Significant differences in gene and protein expression patterns were observed in association with the cumulative number of OXPHOS polymorphic sites. We observed a high degree of homology (~98%) between the blood and liver mitochondrial genomes. A missense POLG p.Gln1236His variant was associated with liver mtDNA copy number. In conclusion, we have demonstrated that OXPHOS genes contain the highest number of hotspot positions associated with a more severe phenotype. The variability of the mitochondrial genomes probably originates from a common germline source; hence, it may explain a fraction of the ‘missing heritability’ of NAFLD. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献