The structure and growth mechanism of Si nanoneedles prepared by plasma-enhanced chemical vapor deposition.

Silicon nanowires and nanoneedles show promise for many device applications in nanoelectronics and nanophotonics, but the remaining challenge is to grow them at low temperatures on low-cost materials. Here we present plasma-enhanced chemical vapor deposition of crystalline/amorphous Si nanoneedles on glass at temperatures as low as 250 °C. High resolution electron microscopy and micro-Raman spectroscopy have been used to study the crystal structure and the growth mechanism of individual Si nanoneedles. The H(2) dilution of the SiH(4) plasma working gas has caused the formation of extremely sharp nanoneedle tips that in some cases do not contain a catalytic particle at the end.

Apolipoprotein E/intrauterine undernutrition interaction and hypercholesterolemia in children.

The inconsistency of data regarding intrauterine programming of cardiovascular risk factors may be largely caused by genetic predisposition and later lifestyle. We analyzed whether low birth weight and apolipoprotein E (Apo E) polymorphism participate in the onset of hypercholesterolemia in children. Our approach was based on hypothesis that genetically enhanced susceptibility of different individuals might influence the effects of intrauterine programming. Two groups were selected from 2000 children at the beginning of an ongoing study: high-cholesterol group (HCG, n=67) and low-cholesterol group as a control (LCG, n=72). Both groups were divided into tertilles according to birth weight and we compared birth weight and apo E gene polymorphism between and within groups. The birth weight in HCG was 0.3 kg lower than the controls (p<0.001). The frequency of apoE4 was 31 % in HCG and only 10 % in LCG. The frequency of apoE4+ genotypes was not significantly different between tertilles based on birth weight in HCG. We suppose that intrauterine undernutrition, demonstrated by a lower birth weight, participates in the development of hypercholesterolemia already in childhood. The effects of low birth weight and the candidate gene - apoE, are synergic.

Reduction of proteinuria during intensified antihypertensive therapy in children after renal transplantation.

BACKGROUND: Proteinuria together with hypertension are known risk factors for poor allograft as well as patient survivals after renal transplantation. In adults, proteinuria can be reduced by lowering blood pressure and by using angiotensin-converting enzyme inhibitors. In children, no study has investigated the antiproteinuric effects of antihypertensive therapy. Herein we investigated changes in proteinuria among a subgroup of children with proteinuria>or=200 mg/m2d in an interventional study primary aimed to improve the efficacy of antihypertensive therapy. PATIENTS AND METHODS: Twelve children with proteinuria>or=200 mg/m2d were included in the study. Proteinuria was investigated at baseline and at 1 year after changes in antihypertensive therapy. Blood pressure (BP) was measured using ambulatory BP monitoring. RESULTS: The median protein excretion of 226 mg/m2/d (range, 41-1478 mg/m2/d) at 1 year before the study did not change significantly at study baseline (278 mg/m2/d; range, 205-1264 mg/m2/d), but decreased significantly to 199 mg/m2/d (range, 65-749 mg/m2/d) after 1 year (P<.05 vs baseline). The number of antihypertensive drugs was increased from 1.6+/-1.0 to 2.2+/-0.9 drugs/patient after 1 year (P<.05). The use of different classes of antihypertensive drugs did not change significantly. Mean ambulatory systolic and diastolic BP at daytime and diastolic BP at nighttime did not change significantly after 1 year; mean ambulatory systolic BP at night decreased from 1.60+/-1.54 to 1.04+/-0.97 standard deviation score (P<.05). Graft function did not change significantly. CONCLUSION: We demonstrated that proteinuria among children after renal transplantation was reduced by intensified antihypertensive therapy using all classes of antihypertensive drugs.