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991.
We report the unique depiction of brown adipose tissue (BAT) by magnetic resonance imaging (MRI) and computed tomography (CT) in a human 3-month-old infant. Based on cellular differences between BAT and more lipid-rich white adipose tissue (WAT), chemical-shift MRI and CT were both capable of generating distinct signal contrasts between the two tissues and against surrounding anatomy, utilizing fat-signal fraction metrics in the former and x-ray attenuation values in the latter. While numerous BAT imaging experiments have been performed previously in rodents, the identification of BAT in humans has only recently been described with fusion positron emission and computed tomography in adults. The imaging of BAT in children has not been widely reported and, furthermore, MRI of human BAT in general has not been demonstrated. In the present work, large bilateral supraclavicular BAT depots were clearly visualized with MRI and CT. Tissue identity was subsequently confirmed by histology. BAT has important implications in regulating energy metabolism and nonshivering thermogenesis and has the potential to combat the onset of weight gain and the development of obesity. Current findings suggest that BAT is present in significant amounts in children and that MRI and CT can differentiate BAT from WAT based on intrinsic tissue properties.  相似文献   
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HALT PKD consists of two ongoing randomized trials with the largest cohort of systematically studied patients with autosomal dominant polycystic kidney disease to date. Study A will compare combined treatment with an angiotensin-converting inhibitor and receptor blocker to inhibitor alone and standard compared with low blood pressure targets in 558 early-stage disease patients with an eGFR over 60 ml/min per 1.73 m(2). Study B will compare inhibitor-blocker treatment to the inhibitor alone in 486 late-stage patients with eGFR 25-60 ml/min per 1.73 m(2). We used correlation and multiple regression cross-sectional analyses to determine associations of baseline parameters with total kidney, liver, or liver cyst volumes measured by MRI in Study A and eGFR in both studies. Lower eGFR and higher natural log-transformed urine albumin excretion were independently associated with a larger natural log-transformed total kidney volume adjusted for height (ln(HtTKV)). Higher body surface area was independently associated with a higher ln(HtTKV) and lower eGFR. Men had larger height-adjusted total kidney volume and smaller liver cyst volumes than women. A weak correlation was found between the ln(HtTKV) and natural log-transformed total liver volume adjusted for height or natural log liver cyst volume in women only. Women had higher urine aldosterone excretion and lower plasma potassium. Thus, our analysis (1) confirms a strong association between renal volume and functional parameters, (2) shows that gender and other factors differentially affect the development of polycystic disease in the kidney and liver, and (3) suggests an association between anthropomorphic measures reflecting prenatal and/or postnatal growth and disease severity.  相似文献   
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A new paediatric multisystem inflammatory syndrome, linked to SARS-CoV-2, has been described. The clinical picture is variable and is associated with an active or recent infection due to SARS-CoV-2. A review of the existing literature by a multidisciplinary group of paediatric specialists is presented in this document. Later, they make recommendations on the stabilisation, diagnosis, and treatment of this syndrome.  相似文献   
998.

Purpose

Cryoballoon ablation of the pulmonary veins (CAPV) is a new technique that could have similar results to radiofrequency procedures, but with fewer complications. We analyzed the outcomes and safety of this technique in a consecutive cohort of patients with atrial fibrillation (AF).

Methods

A total of 63 patients with paroxysmal (n?=?40) or persistent (n?=?23) AF were studied. Patient follow-up was performed at 3 months and then every 6 months with 72-h continuous electrocardiographic recordings.

Results

A total of 262 pulmonary veins were treated; 60.3 % of the cases presented normal pulmonary vein drainage with 4 pulmonary veins, and 23.8 % of the cases presented a common left-sided antrum. Complete isolation of all veins was achieved in 95.2 % of cases with 10.3?±?2.8 (mean?±?standard deviation) applications per patient. Transient right phrenic nerve injury was the most common complication (4.7 %). Median follow-up was 5.5 months. The probability of being free of recurrence at 1 and 2 years was, respectively, 86.2 and 72.2 % for paroxysmal AF and 49 and 36.4 % for persistent AF (P?=?0.012). Patients with structural heart disease experienced recurrence more often than patients with a normal heart (62.5 versus 24.5 %; P?=?0.03).

Conclusions

CAPV appears to be a safe and effective procedure for the treatment of patients with AF, particularly those with paroxysmal AF and no structural heart disease.  相似文献   
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