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31.
Neuroendocrine tumors, also known as carcinoid tumors, behave like benign tumors; however, they show the characteristics of carcinoma. While more than 80% of the neuroendocrine tumors found in the liver are metastatic, primary hepatic neuroendocrine tumors are very rare. Five patients with hepatic mass who admitted to our clinic between August 2003 and July 2007 were treated surgically. Ultrasonography, computerized tomography and magnetic resonance imaging were performed in all patients. Endoscopy and colonoscopy were conducted to exclude malignancy of other sites. Hepatectomy was carried out in all patients. Diagnosis was confirmed with immunohistochemical examination. The five patients treated surgically were diagnosed as primary hepatic neuroendocrine tumor histopathologically. Abdominal pain was the most common complaint of all patients. Hepatectomy was conducted in all patients due to tumors originating from the liver lobes. Only one patient (Case 2) underwent transarterial chemoembolization before hepatectomy to reduce tumor bleeding. Owing to tumor recurrence on the left lobe of the liver in Case 2, transarterial chemoembolization was performed four years after hepatectomy. R0 resection was achieved in two patients (Cases 1 and 3). In conclusion, primary hepatic neuroendocrine tumors are very rare and asymptomatic tumors. Thus, high-sensitive laboratory and imaging examinations are required. At present, hepatectomy remains the main treatment for primary hepatic neuroendocrine tumor.  相似文献   
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Male hypogonadism is defined as the deficiency of testosterone or sperm production synthesized by testicles or the deficiency of both. The reasons for hypogonadism may be primary, meaning testicular or secondary, meaning hypothalamohypophyseal. In hypogonadotropic hypogonadism (HH), there is indeficiency in gonadotropic hormones due to hypothalamic or hypophyseal reasons. Gonadotropin-releasing hormone (GnRH) is an important stimulant in releasing follicular stimulant hormone (FSH), mainly luteinizing hormone (LH). GnRH omitted is under the effect of many hormonal or stimulating factors. Kisspeptin is present in many places of the body, mostly in hypothalamic anteroventral periventricular nucleus and arcuate nucleus. Kisspeptin has a suppressor effect on the metastasis of many tumors such as breast cancer and malign melanoma metastases, and is called “metastin” for this reason. Kisspeptin is a strong stimulant of GnRH. In idiopathic hypogonadotropic hypogonadism (IHH) etiology, there is gonadotropic hormone release indeficiency which cannot be clearly described.

A total of 30 male hypogonatropic hypogonadism diagnosed patients over 30 years of age who have applied to Haydarpasa Education Hospital Endocrinology and Metabolic Diseases Service were included in the study. Compared to the control group, the effect of kisspeptin on male patients with hypogonatropic hypogonadism and on insulin resistance developing in hypogonadism patients was investigated in our study.

A statistically significant difference was detected between average kisspeptin measurements of the groups (p?The reason for high kisspeptin levels in the patient group compared to the control group makes us consider that there may be a GPR54 resistance or GnRH neuronal transfer pathway defect. When patients and control groups were compared for HOMA-IR, the difference was not statistically significant. It is considered that kisspeptin is one of the reasons for hypogonatropic hypogonadism and has less effect on insulin resistance.  相似文献   
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T-cell prolymphocytic leukemia (T-PLL) is mostly characterized by aberrant expansion of small- to medium-sized prolymphocytes with a mature post-thymic phenotype, high aggressiveness of the disease and poor prognosis. However, T-PLL is more heterogeneous with a wide range of clinical, morphological, and molecular features, which occasionally impedes the diagnosis. We hypothesized that T-PLL consists of phenotypic and/or genotypic subgroups that may explain the heterogeneity of the disease. Multi-dimensional immuno-phenotyping and gene expression profiling did not reveal clear T-PLL subgroups, and no clear T-cell receptor a or b CDR3 skewing was observed between different T-PLL cases. We revealed that the expression of microRNA (miRNA) is aberrant and often heterogeneous in T-PLL. We identified 35 miRNA that were aberrantly expressed in T-PLL with miR-200c/141 as the most differentially expressed cluster. High miR- 200c/141 and miR-181a/181b expression was significantly correlated with increased white blood cell counts and poor survival. Furthermore, we found that overexpression of miR-200c/141 correlated with downregulation of their targets ZEB2 and TGFbR3 and aberrant TGFb1- induced phosphorylated SMAD2 (p-SMAD2) and p-SMAD3, indicating that the TGFb pathway is affected in T-PLL. Our results thus highlight the potential role for aberrantly expressed oncogenic miRNA in T-PLL and pave the way for new therapeutic targets in this disease.  相似文献   
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Lipids are essential for healthy infant growth and development. The structural complexity of lipids in human milk is not present in infant milk formula (IF). A concept IF was developed mimicking more closely the structure and composition of human milk fat globules. The current study evaluates whether a concept IF with large, milk phospholipid-coated lipid droplets (mode diameter 3 to 5 μm) is equivalent to standard IF with regard to growth adequacy and safety in healthy, term Asian infants. In this randomized, double-blind, controlled trial, infants were randomized after parents decided to introduce formula. Infants received a standard IF with (Control) or without the specific prebiotic mixture scGOS/lcFOS (9:1 ratio; Control w/o prebiotics), or a Concept IF with large, milk phospholipid-coated lipid droplets and the prebiotic mixture. A group of 67 breastfed infants served as a reference. As a priori defined, only those infants who were fully intervention formula-fed ≤28 days of age were included in the equivalence analysis (Control n = 29; Control w/o prebiotics n = 28; Concept n = 35, per-protocol population). Primary outcome was daily weight gain during the first four months of life, with the difference between the Concept and Control as the key comparison of interest. Additionally, adverse events, growth and tolerance parameters were evaluated. Equivalence of daily weight gain was demonstrated between the Concept and Control group after additional correction for ethnicity and birthweight (difference in estimated means of 0.1 g/d, 90%CI [−2.30, 2.47]; equivalence margin +/− 3 g/d). No clinically relevant group differences were observed in secondary growth outcomes, tolerance outcomes or number, severity or relatedness of adverse events. This study corroborates that an infant formula with large, milk phospholipid-coated lipid droplets supports adequate growth and is well tolerated and safe for use in healthy infants.  相似文献   
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Benign Familial Neonatal Convulsions (BFNC) are a rare epilepsy disorder with an autosomal-dominant inheritance. It is linked to mutations in the potassium channel genes KCNQ2 and KCNQ3. These encode for Kv7.2 and Kv7.3 potassium ion channels, which produce an M-current that regulates the potential firing action in neurons through modulation of the membrane potential. We report on the biophysical and biochemical properties of V589X, T359K and P410fs12X mutant-KCNQ2 ion channels that were detected in three BFNC families. Mutant KCNQ2 cDNAs were co-expressed with WT-KCNQ2 and KCNQ3 cDNAs in HEK293 cells to mimic heterozygous expression of the KCNQ2 mutations in BFNC patients. The resulting potassium currents were measured using patch-clamp techniques and showed an approximately 75% reduction in current and a depolarized shift in the voltage dependence of activation. Furthermore, the time-constant of activation of M-currents in cells expressing T359K and P410fs12X was slower compared to cells expressing only wild-type proteins. Immunofluorescent labeling of HEK293 cells stably expressing GFP-tagged KCNQ2-WT or mutant α-subunits indicated cell surface expression of WT, V589X and T359K mutants, suggesting a loss-of-function, while P410fs12X was predominantly retained in the ER and sub-cellular compartments outside the ER suggesting an effectively haplo-insufficient effect.  相似文献   
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The objective of this research was to examine the contribution of a moderately high fat (MHF) diet to the development of salt-sensitive hypertension in obese Zucker rats. Lean and obese Zucker rats were fed either a MHF diet or a diet of standard rat chow (control diet) for 10 weeks. From week 4 through week 10, the drinking water was supplemented with 1% NaCl. Blood pressure was measured weekly, and urinary excretion of nitric oxide metabolites (NO(x)) was determined at weeks 4 and 10. At week 10, renal nitric oxide synthase (NOS) activity was assessed in kidney homogenates. Blood pressures of obese, but not lean, rats on the MHF fat diet were significantly increased by salt-supplementation, whereas blood pressures of rats on the control diet were not appreciably affected. NO(x) excretion was increased in response to salt-supplementation in rats on the control diet, with the effect being particularly dramatic in obese rats. After salt-supplementation, NO(x) excretion by rats on the MHF diet was lower than rats on the control diet. In obese rats on the MHF diet, this decrease in NO production was accompanied by a reduction in renal NOS activity. These results indicate that obese rats are more inclined than lean rats to develop diet-induced hypertension in response to a moderately high fat, salt-supplemented diet. Furthermore, they suggest that MHF diet-induced defects in NO production may promote the salt-sensitivity of blood pressure in obese Zucker rats, which appear to require more NO to maintain blood pressure during a salt challenge.  相似文献   
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