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41.
To characterize a population of pediatric high-grade astrocytoma (HGA) patients by confirming the proportion with a correct diagnosis, and determine prognostic factors for survival in a subset diagnosed with uniform pathologic criteria. Sixty-three children diagnosed with HGA were treated at the Johns Hopkins Hospital between 1977 and 2004. A single neuropathologist (P.C.B.) reviewed all available histologic samples (n = 48). Log-rank analysis was used to compare survival by patient, tumor, and treatment factors. Median follow-up was 16 months for all patients and 155 months (minimum 54 months) for surviving patients. Median survival for all patients (n = 63) was 14 months with 10 long-term survivors (survival >48 months). At initial diagnosis, 27 patients were grade III (43%) and 36 grade IV (57%). Forty-eight patients had pathology slides available for review, including seven of ten long-term surviving patients. Four patients had non-HGA pathology, all of whom were long term survivors. The remaining 44 patients with confirmed HGG had a median survival of 14 months and prognostic analysis was confined to these patients. On multivariate analysis, five factors were associated with inferior survival: performance status (Lansky) <80% (13 vs. 15 months), bilaterality (13 vs. 19 months), parietal lobe location (13 vs. 16 months), resection less than gross total (13 vs. 22 months), and radiotherapy dose <50 Gy (9 vs. 16 months). Among patients with more than one of the five adverse factors (n = 27), median survival and proportion of long-term survivors were 12.9 months and 0%, compared with 41.4 months and 18% for patients with 0–1 adverse factors (n = 17). In an historical cohort of children with HGA, the potential for long term survival was confined to the subset with less than two of the following adverse prognostic factors: low performance status, bilaterality, parietal lobe site, less than gross total resection, and radiotherapy dose <50 Gy. Pathologic misdiagnosis should be suspected in patients who are long term survivors of a pediatric high grade astrocytoma.  相似文献   
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44.
Hypertrophic cardiomyopathy (HCM) is entering a phase of intense translational research that holds promise for major advances in disease‐specific pharmacological therapy. For over 50 years, however, HCM has largely remained an orphan disease, and patients are still treated with old drugs developed for other conditions. While judicious use of the available armamentarium may control the clinical manifestations of HCM in most patients, specific experience is required in challenging situations, including deciding when not to treat. The present review revisits the time‐honoured therapies available for HCM, in a practical perspective reflecting real‐world scenarios. Specific agents are presented with doses, titration strategies, pros and cons. Peculiar HCM dilemmas such as treatment of dynamic outflow obstruction, heart failure caused by end‐stage progression and prevention of atrial fibrillation and ventricular arrhythmias are assessed. In the near future, the field of HCM drug therapy will rapidly expand, based on ongoing efforts. Approaches such as myocardial metabolic modulation, late sodium current inhibition and allosteric myosin inhibition have moved from pre‐clinical to clinical research, and reflect a surge of scientific as well as economic interest by academia and industry alike. These exciting developments, and their implications for future research, are discussed.  相似文献   
45.

Background and objectives

Left ventricular hypertrophy (LVH) and abnormal left ventricular (LV) geometry predict adverse outcomes in the general and hypertensive populations, but findings in CKD are still inconclusive.

Design, setting, participants, & measurements

We enrolled 445 patients with hypertension and CKD stages 2–5 in two academic nephrology clinics in 1999–2003 who underwent both echocardiography and ambulatory BP monitoring. LVH (LV mass >100 g/m2 [women] and >131 g/m2 [men]) and relative wall thickness (RWT) were used to define LV geometry: no LVH and RWT≤0.45 (normal), no LVH and RWT>0.45 (remodeling), LVH and RWT≤0.45 (eccentric), and LVH and RWT>0.45 (concentric). We evaluated the prognostic role of LVH and LV geometry on cardiovascular (CV; composite of fatal and nonfatal events) and renal outcomes (composite of ESRD and all-cause death).

Results

Age was 64.1±13.8 years old; 19% had diabetes, and 22% had CV disease. eGFR was 39.9±20.2 ml/min per 1.73 m2. LVH was detected in 249 patients (56.0%); of these, 125 had concentric LVH, and 124 had eccentric pattern, whereas 71 patients had concentric remodeling. Age, women, anemia, and nocturnal hypertension were independently associated with both concentric and eccentric LVH, whereas diabetes and history of CV disease associated with eccentric LVH only, and CKD stages 4 and 5 associated with concentric LVH only. During follow-up (median, 5.9 years; range, 0.04–15.3), 188 renal deaths (112 ESRD) and 103 CV events (61 fatal) occurred. Using multivariable Cox analysis, concentric and eccentric LVH was associated with higher risk of CV outcomes (hazard ratio [HR], 2.59; 95% confidence interval [95% CI], 1.39 to 4.84 and HR, 2.79; 95% CI, 1.47 to 5.26, respectively). Similarly, greater risk of renal end point was detected in concentric (HR, 2.33; 95% CI, 1.44 to 3.80) and eccentric (HR, 2.30; 95% CI, 1.42 to 3.74) LVH. Sensitivity analysis using LVH and RWT separately showed that LVH but not RWT was associated with higher cardiorenal risk.

Conclusions

In patients with CKD, LVH is a strong predictor of the risk of poor CV and renal outcomes independent from LV geometry.  相似文献   
46.
The strategy of treatment for patients with adrenal incidentalomas (AI) may depend upon the presence of hormonal hypersecretion. Although alterations of bone turnover have been recently reported, data on bone mineral density (BMD) are not available in AI patients. We evaluated bone turnover and BMD in 32 female AI patients and 64 matched controls. Spinal and femoral BMD were similar in patients and controls. Serum bone GLA protein (6.8+/-3.5 vs. 8.8+/-3.2 ng/mL; P<0.005) and PTH (48.8+/-15.1 vs. 37.2+/-10.9 pg/mL; P<0.0001) were different in patients and controls. Patients were then subdivided into 2 groups: with (n = 8; group A) or without (n = 24; group B) subclinical hypercortisolism. PTH was higher (P<0.05) in group A than in group B and in both groups than in controls (57.1+/-13.6, 46.0+/-14.8, and 37.2+/-10.9 pg/mL, respectively), and bone GLA protein was lower in group A than in group B and controls (3.8+/-2.3, 7.5+/-3.1, and 8.8+/-3.2 ng/mL, respectively; P<0.05). Serum type I cross-linked C telopeptide and fasting urinary deoxypyridinoline/ creatinine were not different in the three groups. BMD at each site was lower (P<0.05) in group A than in group B and controls. Bone mass and metabolism are altered in AI patients with subclinical hypercortisolism and should be taken into account, therefore, when addressing the treatment of choice for these patients.  相似文献   
47.

Background:

Diabetes mellitus (DM) represents by itself a major risk factor for cardiovascular events and the coexistence of obesity with consequent left ventricular volumetric overload could be responsible for further damages on left ventricular function. Aim of this study was to demonstrate the effect of body mass index (BMI) on left ventricular function in diabetes patients with no cardiovascular complications and with normal ejection fraction (EF).

Materials and Methods:

We evaluated 71 stable asymptomatic diabetes patients in optimal medical treatment and 24 healthy controls (C) (45% females; mean age: 58.4 +/− 9.4 years; BMI: 23.5 +/− 1.5). We stratified diabetes patients into two groups according to BMI: BMI <30 kg/m2 (A: 44 patients; 47% females; mean age: 60.9 +/− 6.6 years; BMI: 25.7 +/− 1.9; Diabetes duration: 9.1 +/− 9.5 years); BMI >30 kg/m2 (B: 27 patients; 37% females; mean age: 56.2 +/− 7.8 years; BMI: 33.0 +/− 2.1; Diabetes duration: 8.5 +/− 5.2 years). The following parameters were evaluated by conventional two dimensional (2D) echocardiography (GE VIVID 7) and tissue Doppler imaging (TDI): left ventricular dimensions (LVIDd; PWTd; IVSd), Left Ventricular Volumes (EDV, ESV), EF (by biplane Simpson’s method), Left Ventricular Mass (by ASE formula), peak mitral annular velocity at septal and lateral levels (Sm and Sl). Global longitudinal strain (GLS) was obtained off line by Speckle tracking imaging method using Echopac 10 software.

Results:

Groups A, B were comparable for diabetes duration and glycated hemoglobin level, history of hypertension, and lipid profile. The EF was similar in the three groups, (A: 64 +/− 6%; B: 63 +/− 4%; C: 61 +/−5%; P= NS). LVMass2.7 indexed for height was significantly higher in A and B in comparison with C (A: 45.2 +/− 8.1 g/m2.7; B: 46.1 +/− 9.6 g/m2.7; C: 39.5 +/− 4.9 g/m2.7; P < 0.05). The stroke volume index (SVi) was significantly lower in B vs A (B: 35.3 +/− 5.7 ml/m2; A: 39.3 +/7.1 ml/m2; P = 0.033). GLS was significantly lower in group B respect A and C (C: 20.9 +/− 1.3%; A: -20.3+/−2.6%; B: -19 +/− 2; P < 0.05; P < 0.01).

Conclusions:

In uncomplicated asymptomatic DM patients, the presence of first degree obesity plays an incremental role in adversely affecting left ventricular function and remodeling. The conventional echocardiographic methods such as the EF and the TDI are not so sensitive to identify the early LV dysfunction such as the evaluation of GLS by Speckle Tracking echocardiography. The longitudinal subendocardial fibers dysfunction in diabetes/obese patients could be derived by the complex interaction between metabolic (diabetes) and hemodynamic/endocrine abnormalities.  相似文献   
48.
The relation of exercise-induced left ventricular (LV) outflow tract obstruction to functional capacity in hypertrophic cardiomyopathy (HC) is incompletely defined. Thus, we assessed the patterns of onset of physiologically provoked LV outflow gradients and exercise performance in 74 consecutive patients with HC (age 45 ± 16 years; 74% men) without LV outflow obstruction at rest. The subaortic gradients were measured serially using echocardiography in these 74 patients during maximum, symptom-limited, upright bicycle exercise testing. The time course of the provoked gradients and the relation to exercise performance were assessed. Of the 74 patients, 30 (41%) developed a dynamic LV outflow gradient of ≥30 mm Hg (mean 78 ± 37 mm Hg) during upright exercise testing that correlated highly with the gradients measured with the patients supine during the immediate recovery period (R2 = 0.97). The 16 patients in whom outflow obstruction developed rapidly at low exercise levels (≤5 METs) had a significantly reduced exercise capacity (6.1 ± 1.3 vs 8.0 ± 1.6 METs; p <0.01) compared to the other 14 patients in whom obstruction appeared later at greater exercise levels of >5 METs. The timing of the gradient onset was not predictable from the baseline clinical and echocardiographic features, peak exercise LV outflow tract gradient, or symptoms. In conclusion, in patients with HC without outflow obstruction at rest, the earlier onset of LV outflow tract gradients during physiologic exercise was associated with impaired exercise performance. These findings have provided insights into the determinants of functional impairment in HC and support the potential value of exercise echocardiography in the clinical assessment of patients with HC.  相似文献   
49.
The importance of the genetic component on adipose tissue accumulation has been clearly demonstrated. Among the candidate genes investigated, there are those that regulate thermogenesis and, thus, can affect energy expenditure. The uncoupling proteins (UCPs) are a family of proteins that uncouple respiration leading to generation of heat and increased energy expenditure. Contradictory data indicate that allelic variants in their coding genes might be associated with obesity. In this study we evaluated the role of two allelic variants of the UCP2 gene in obesity and the association with its sub-phenotypic characteristics. To this aim, 360 morbidly obese patients [age: 45 +/- 15 yr, body mass index (BMI): 46 +/- 7 kg/m2] and 103 normal weight subjects (BMI < 24 kg/m2) were genotyped for the 45 bais-pair (bp) insertion/deletion (I/D) in the 3'-untraslated region of exon 8 of the UCP2 gene while the presence of an Ala/Val substitution at codon 55 (Ala55Val) of the same gene was studied in 104 obese and 50 lean subjects. Patients also underwent a study protocol including measurements of BMI, waist-to-hip ratio (WHR), resting energy expenditure (REE), energy intake, fat mass (FM) and free fat mass (FFM), total cholesterol (TCH), high density lipoprotein (HDL) cholesterol, triacylglyceroles (TG), leptin levels, basal glucose, immunoreactive insulin (IRI), glycated haemoglobin (HbA1c), insulin sensitivity and thyroid hormones. No significant association between the two polymorphisms studied and the clinical, metabolic and anthropometric parameters characteristic of the obese phenotype was found. These results, in accordance with similar findings previously obtained in other ethnic groups, suggest that these two UCP2 allelic variants may not have a direct role in the pathogenesis and development of obesity.  相似文献   
50.
OBJECTIVES: To examine the utility of the different elements of screening expatriates and travellers returned from the tropics for parasitic disease (exposure history, symptoms, examination and laboratory tests). METHODS: In phase 1 (conducted prospectively 1990-91), 1029 asymptomatic returnees had a detailed questionnaire and interview on risk-behaviour, physical examination and laboratory tests. In phase 2 (1997-98), 510 consecutive patients referred for routine screening (276 symptomatic and 234 asymptomatic) were screened with laboratory tests. RESULTS: Exposure history did not correlate reliably with parasite burden. In phase 1 physical examination revealed 387 abnormalities, only three of which indicated parasitic disease. Schistosomal serology was positive in 11% (CI 9-13) of these asymptomatic cases including patients with light or no reported freshwater exposure. Stool microscopy was positive in 19% (CI 16-22) of cases not correlated with reported eating habits, and eosinophilia was present in 8% (CI 6-10). In phase 2 reported symptoms did not correlate with parasitic disease. Schistosomiasis was present in 15% (CI 13-24) of asymptomatic and 18% (CI 13-22) of symptomatic individuals (OR 1.2 P = 0.46); stool microscopy was positive in 14% of both symptomatic and asymptomatic patients, and eosinophilia in 9% of symptomatic and 6% of asymptomatic individuals. CONCLUSION: Potentially serious asymptomatic infection is common in travellers. Detailed exposure history, symptom history and physical examination added little to detecting cases. Stool microscopy, schistosomal serology and eosinophil count all had good yield. Filarial serology had low yield in patients without eosinophilia.  相似文献   
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