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21.
Fatty liver can present as focal, diffuse, heterogeneous, and multinodular forms. Being familiar with various patterns of steatosis can enable correct diagnosis. In patients with equivocal findings on ultrasonography, magnetic resonance imaging can be used as a problem solving tool. New techniques are promising for diagnosis and follow-up. We review imaging patterns of steatosis and new quantitative methods such as proton density fat fraction and magnetic resonance elastography for diagnosis of nonalcoholic fatty liver disease in children.Nonalcoholic fatty liver disease (NAFLD) is as widely encountered in children as in adults, with an estimated prevalence of 9.6% (1). It occurs due to accumulation of triglyceride in hepatocytes without alcohol ingestion. Nonalcoholic steatohepatitis (NASH) was first defined in children in 1983 (2). NAFLD includes a broad range of clinicopathologic features ranging from simple steatosis (fat with inflammation and/or fibrosis), steatohepatitis/NASH to cirrhosis. Some other diseases of liver can also cause hepatic steatosis including hepatitis B and C, Wilson’s disease, α-1-antitrypsin deficiency, autoimmune hepatitis, drug-induced liver injury (valproate, methotrexate, tetracycline, amiodarone, and prednisone), and total parenteral nutrition (3). Furthermore, fatty liver is a risk factor for cirrhosis, diabetes, and cardiovascular disease.In clinical practice, the diagnosis of NAFLD is made by increased serum ALT and/or presence of enlarged echogenic liver in ultrasonography. Being overweight or obese, and/or insulin resistance are highly indicative but not absolutely necessary for diagnosing NAFLD (4). The gold standard for diagnosis is liver biopsy, which additionally provides semi-quantitative analysis of NASH damage in children (5). It is an expensive, invasive procedure with a risk of morbidity (0.06%–0.35%) and mortality (0.01%–0.1%) (6).The evaluation of liver fat in children via noninvasive imaging modalities is needed to avoid complications of biopsy and for follow-up. Main imaging modalities for the assessment of pediatric NAFLD are ultrasonography (US) and magnetic resonance imaging (MRI). Computed tomography is the other imaging method for liver fat assessment, but ionizing radiation is a major drawback in children (7). Assessment of fat accumulation may cause diagnostic dilemmas and confusion due to manifestations with unusual structural patterns and imaging appearance of the liver. This article reviews the histopathology of pediatric NAFLD, radiologic evaluation and different structural patterns of childhood NAFLD/NASH on US and MRI. We also discuss diagnostic pitfalls and briefly review new imaging techniques.  相似文献   
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[Purpose] Although oxidative stress is known to be present in rheumatoid arthritis (RA), the effects of exercise on oxidative parameters are unknown. The aim of this study was to investigate the effects of acute aerobic exercise on serum oxidant and antioxidant levels in patients with RA. [Subjects and Methods] Sixteen patients with RA and 10 age-matched healthy volunteers participated in this study. All participants wore polar telemeters and walked on a treadmill for 30 minutes at a speed eliciting 60–75% of maximal heart rates. Blood samples were obtained before, immediately and 24 hours after exercise and malondialdehyde (MDA) and total sulfhydrile group (RSH) levels were measured. [Results] Both groups had similar heart rates during the test but the treadmill speed of the RA patients was significantly lower than that of the healthy volunteers. Serum MDA levels were lower than in both groups immediately after exercise, with greater decrements in the RA patients than controls. MDA levels returned to baseline 24 hours after the exercise only in the controls; they remained low in the RA patients. There was a slight increase in serum RSH levels after exercise compared to baseline in both groups. [Conclusion] Moderate intensity treadmill exercise did not have any adverse effect on the oxidant-antioxidant balance. The results suggest that such an exercise may be safely added to the rehabilitation program of RA for additional antioxidant effects. Morever, this antioxidant environment is maintained longer in RA patients.Key words: Aerobic exercise, Oxidative status, Rheumatoid arthritis  相似文献   
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Blood pressure was measured in 3317 men, aged 40-59, working in H. Cegielski Metal Works in Poznań. The average systolic pressure for the whole population was 130.9 mmHg (SE = 17.90). The average diastolic pressure was 83.7 mmHg (SE = 10.03). The systolic, diastolic and mixed systolic-diastolic hypertension was found in 539 men which makes 16.3% of the study group. The borderline systolic hypertension was found in 327 men i.e. 9.9%, borderline diastolic hypertension in 267 men i.e. 8.0%. Both systolic and diastolic borderline hypertension displayed 339 men i.e. 10.2% of the study group. So, borderline hypertension (systolic, diastolic and systolic-diastolic) was found in 933 men which makes 28.1% of the population under the study.  相似文献   
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Introduction and Objective: The present study aims to quantitatively evaluate the right ventricle (RV) function by means of transthoracic echocardiography in normal children and childhood congenital heart disease patients with pulmonary hypertension. Patients and Methods: This study was conducted in a cohort including 40 healthy children and 30 pediatric patients with pulmonary hypertension who were diagnosed under close surveillance at the study center between October 2009 and November 2010. Results: Statistically significant differences were found between the patient and control groups for the right ventricle myocardial performance index (RVMPI), the left ventricle myocardial performance index (LVMPI), the tricuspid valve systolic flow velocity (Ts), the ratio of systolic pulmonary artery pressure to the right ventricle outflow tract systolic flow velocity time integral (sPAP/RVOT VTI), and the ratio of systolic pulmonary artery pressure to right ventricle outflow tract systolic flow velocity time integral × heart rate (sPAP/[RVOT VTI×HR]). When the children were divided into three groups based on their pulmonary vascular resistance significant differences emerged that predicted an increasing severity of RV dysfunction. Significant differences were also observed for the RVMPI, the LVMPI, and the Ts as well as for echocardiographic pulmonary flow (Qp) and systemic flow (Qs). Discussion: The present study demonstrates that echocardiographic parameters can be used for the quantitative detection of RV dysfunction in childhood congenital heart disease patients with high pulmonary artery pressure (systolic, diastolic, and mean) or pulmonary vascular resistance.  相似文献   
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PURPOSE: To investigate the contribution of HCV infection to insulin resistance in chronic haemodialysis patients. MATERIALS AND METHODS: The study was performed with 55 patients who were on regular haemodialysis therapy three times per week. Of the 55 patients, 34 (20 females and 14 males with an average age of 40.9 years) were anti-HCV (+) and were defined as the HCV (+) group. The remaining 21 patients (8 females and 11 males with an average age of 50 years) were negative for HCV and other viral markers and were defined as the HCV (-) group. BMI of all patients were below 27. Insulin resistance (IR) was calculated according to the HOMA formula and patients were called HOMA-IR (+) if their HOMA scores were higher than 2.5. All of the HOMA-IR (+) patients in both groups were called the HOMA-IR (+) subgroup. None of the patients had a history of drug use or any diseases that were related to insulin resistance except uremia. In both groups and the healthy control group, insulin and glucose levels were studied at three different venous serum samples taken at 5- minute intervals after 12 hours of fasting. Other individual variables were studied at venous serum samples taken after 12 hours of fasting. RESULTS: HOMA scores were (3)2.5 in 22 of 34 HCV (+) patients (64.7%) and 7 of 21HCV (-) patients (33.33%) (p=0.024). Insulin levels of HCV (+) group (13.32 +/- 9.44mIU/mL) were significantly higher than HCV (-) (9.07 +/- 7.39mIU/mL) and the control groups (6.40 +/- 4.94mIU/ mL) (p=0.039 and p=0.021 respectively). HCV (+) patients were younger (40.94 +/- 17.06 and 52.62 +/- 20.64 years, respectively) and had longer dialysis duration (7.18 +/- 3.61 and 2.91 +/- 2.69 years, respectively). Significant positive correlations of HOMA score with insulin (r=0.934, p=0.000) and fasting glucose levels (r=0.379, p=0.043) were found in the HOMA- IR (+) subgroup. Also, a significant positive correlation was found between ALT and insulin levels in the HOMA IR (+) subgroup. C-peptide levels of both HCV (+) and (-) groups were significantly higher than the control group (p < 0.001). There were not any significant correlations between HOMA score and some of the other individual variables including levels of triglyceride, ferritin, ALT, iPTH and Mg in any of the groups. CONCLUSION: In chronic haemodialysis patients; HCV infection is related to a high prevalence of insulin resistance, higher insulin and glucose levels.  相似文献   
29.
Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved signiifcantly. These ifndings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats.  相似文献   
30.
Enthesopathy is pathology of bony insertions of tendons, ligaments or joint capsules. It is a frequent finding in rheumatic diseases, like ankylosing spondylitis (AS) and Behçet’s disease. Musculoskeletal complaints are common in patients with familial Mediterranean fever (FMF), and these could be a clinical manifestation of enthesopathy. Hence, we investigated the possible association between FMF and enthesopathy. Fifty-six patients with FMF and 11 patients with FMF-associated spondyloarthropathy (FMFS) were enrolled. Forty-seven healthy individuals and 36 patients with AS formed the healthy and diseased control groups. Musculoskeletal complaints were meticulously questioned, and all patients underwent a detailed physical and ultrasonographic (US) examination of the lower limbs. US scorings of enthesopathy was performed according to the Glasgow Ultrasound Enthesitis Scoring System (GUESS). Demographic data, disease characteristics, MEFV genotypes and HLA B27 results were retrieved from the medical records. Patient-reported pain and physical examination findings consistent with enthesopathy were frequent in all groups with the highest prevalence in the FMFS group. Heel was the most common region affected in all patient groups. FMF patients harboring M694 V variant had higher GUESS scores compared to patients with other variants (2.78 ± 2.43 vs. 1.37 ± 1.67, p = 0.026). There was no statistically significant difference in the mean ± SD GUESS scores between healthy subjects and those FMF patients with genetic variants other than M694 V (1.38 ± 1.42 vs. 1.37 ± 1.67, p > 0.05). Enthesopathy may not be a feature of general FMF population; rather, it might be specifically associated with the presence of M694 V variant. Our results further support the previous evidence regarding M694 V mutation and spondyloarthropathy association.  相似文献   
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