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21.
Eustachian valve (EV) is a vestige of the valve of the inferior vena cava which directs the umbilical vein blood through open foramen ovale in fetal life. Following birth it gradually regresses, but it may persist in variable size, shape, and thickness as a functionless and benign structure. However, there are reports suggesting that persistent EV may not be completely innocent. It has been accused of being a predisposing cause of patent foramen ovale and paradoxical embolism and also interfering with transseptal interventional procedures. It may serve as a site of infective vegetations and be mistaken as a tumor or thrombus. In the present case, an octopus‐like thrombus attached to the EV was delineated with the utility of two‐dimensional and real time three‐dimensional transesophageal echocardiography. EV was considered to play an essential role in preventing potential pulmonary embolism.  相似文献   
22.
Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.   相似文献   
23.

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
24.

Purpose

To evaluate the diagnostic performance of 68Ga-DOTATATE 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT), 18F-FDG PET/CT and 131I-MIBG scintigraphy in the mapping of metastatic pheochromocytoma and paraganglioma.

Materials and Methods

Seventeen patients (male = 8, female = 9; age range, 13–68 years) with clinically proven or suspicious metastatic pheochromocytoma or paraganglioma were included in this prospective study. Twelve patients underwent all three modalities, whereas five patients underwent 68Ga-DOTATATE and 131I-MIBG without 18F-FDG. A composite reference standard derived from anatomical and functional imaging findings, along with histopathological information, was used to validate the findings. Results were analysed on a per-patient and on per-lesion basis. Sensitivity and accuracy were assessed using McNemar’s test.

Results

On a per-patient basis, 14/17 patients were detected in 68Ga-DOTATATE, 7/17 patients in 131I-MIBG, and 10/12 patients in 18F-FDG. The sensitivity and accuracy of 68Ga-DOTATATE, 131I-MIBG and 18F-FDG were (93.3 %, 94.1 %), (46.7 %, 52.9 %) and (90.9 %, 91.7 %) respectively. On a per-lesion basis, an overall of 472 positive lesions were detected; of which 432/472 were identified by 68Ga-DOTATATE, 74/472 by 131I-MIBG, and 154/300 (patient, n = 12) by 18F-FDG. The sensitivity and accuracy of 68Ga-DOTATATE, 131I-MIBG and 18F-FDG were (91.5 %, 92.6 % p < 0.0001), (15.7 %, 26.0 % p < 0.0001) and (51.3 %, 57.8 % p < 0.0001) respectively. Discordant lesions were demonstrated on 68Ga-DOTATATE, 131I-MIBG and 18F-FDG.

Conclusions

Ga-DOTATATE PET/CT shows high diagnostic accuracy than 131I-MIBG scintigraphy and 18F-FDG PET/ CT in mapping metastatic pheochromocytoma and paraganglioma.  相似文献   
25.
Acc2-/- mutant mice, when fed a high-fat/high-carbohydrate (HF/HC) diet, were protected against diet-induced obesity and diabetes. To investigate the role of acetyl-CoA carboxylase 2 (ACC2) in the regulation of energy metabolism in adipose tissues, we studied fatty acid and glucose oxidation in primary cultures of adipocytes isolated from wild-type and Acc2-/- mutant mice fed either normal chow or a HF/HC diet. When fed normal chow, oxidation of [14C]palmitate in adipocytes of Acc2-/- mutant mice was approximately 80% higher than in adipocytes of WT mice, and it remained significantly higher in the presence of insulin. Interestingly, in addition to increased fatty acid oxidation, we also observed increased glucose oxidation in adipocytes of Acc2-/- mutant mice compared with that of WT mice. When fed a HF/HC diet for 4-5 months, adipocytes of Acc2-/- mutant mice maintained a 25% higher palmitate oxidation and a 2-fold higher glucose oxidation than WT mice. The mRNA level of glucose transporter 4 (GLUT4) decreased several fold in the adipose tissue of WT mice fed a HF/HC diet; however, in the adipose tissue of Acc2-/- mutant mice, it was 7-fold higher. Moreover, lipolysis activity was higher in adipocytes of Acc2-/- mutant mice compared with that in WT mice. These findings suggest that continuous fatty acid oxidation in the adipocytes of Acc2-/- mutant mice, combined with a higher level of glucose oxidation and a higher rate of lipolysis, are major factors leading to efficient maintenance of insulin sensitivity and leaner Acc2-/- mutant mice.  相似文献   
26.
BACKGROUND/AIMS: 5-Fluorouracil-based chemoradiotherapy is the most widely used treatment modality in the adjuvant treatment of rectal cancer. Capecitabine represents a valuable alternative to 5-Fluorouracil in this situation. METHODOLOGY: Patients with stage II and stage III rectal adenocarcinoma, who were included in this analysis, received adjuvant chemoradiotherapy consisting of external-beam radiotherapy (50.4-54Gy) either with 5-Fluorouracil at a median dose of 300 mg/m2/day by protracted venous infusion for 5 days a week, or capecitabine at a median dose of 1650 mg/m2/day for 5 days a week after surgery. The data concerning the toxicity and the efficacy of the treatments were compared in patients treated with 5-Fluorouracil- and capecitabine-based chemoradiotherapy. RESULTS: Forty-three patients received 5-Fluorouracil, and 24 patients received capecitabine during adjuvant radiotherapy. Although there were no differences between the groups in terms of toxicity rates, distant metastasis-free survival, disease-free survival, and overall survival rates; a trend for improved loco-regional recurrence-free survival rate was observed in the capecitabine arm (p = 0.063). CONCLUSIONS: Capecitabine is at least as effective as 5-Fluorouracil in the postoperative treatment of rectal adenocarcinoma. Considering the trend for improved loco-regional recurrence-free survival rate in the capecitabine arm, it seems that the drug exerts better synergy with radiotherapy in this situation.  相似文献   
27.
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29.

Background:

The hepatitis B virus is an important healthcare problem. According to current clinical practice, a liver biopsy is required for the diagnosis and treatment of chronic liver disease. However, a liver biopsy is an invasive, inconvenient procedure, which requires an expert pathologist opinion. Therefore requirement of biochemical tests, which are considered to indicate hepatic fibrosis and may be repeated easily, increases gradually today.

Objectives:

This study evaluated the correlation between hepatic fibrosis and routine laboratory values in patients with chronic hepatitis B.

Patients and Methods:

The files of 456 patients with CHB (chronic hepatitis B) who were referred to the infectious diseases and clinical microbiology clinic between January 2009 and March 2012 were screened retrospectively. Liver biopsy samples were examined according to Ishak scoring. Laboratory parameters and histopathology reports were recorded, and correlations between the fibrosis grade and laboratory parameters were analyzed.

Results:

There were 320 male and 136 female patients, with a mean age 36.7 ± 12.1 years. According to liver biopsy results, a low fibrosis score (stage 0-2) was detected in 281 patients (61.6%), and a high fibrosis score (stage 3-5) was detected in 175 patients (38.4%). Patients with a high fibrosis score had significantly higher ALT (alanine amino transferase), AST (aspartate aminotransferase), and HBV-DNA values and a significantly lower platelet count compared with those with a low fibrosis score (P = 0.001, 0.001, 0.025, and 0.001, respectively). A positive correlation was detected between the fibrosis score and age, BMI, HAI, ALT, and AST values, and a negative correlation was detected between the fibrosis score and albumin and platelet counts. In the regression analysis performed to evaluate the factors associated with high-stage fibrosis, fibrosis was determined to be associated with thrombosis, ALT, and gender. The results of the regression analysis demonstrated that the risk of fibrosis was 4.6 fold higher in men.

Conclusions:

According to the results obtained in our study, advanced age, higher BMI, AST, ALT, and HBV-DNA levels, and low albumin and platelet levels are correlated with advanced fibrosis in patients with CHB.  相似文献   
30.
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