Prenatal exclusion of Leigh syndrome due to T8993C mutation in the mitochondrial DNA

Leigh syndrome (LS) is a mitochondrial encephalopathy that is caused by a mutation either in the mitochondrial DNA (mtDNA) or in the nuclear encoded genes of the mitochondrial proteins. Prenatal diagnosis of defects in the mtDNA is usually problematic because of mtDNA heteroplasmy and tissue specificity. However, the mutations T8993 G/C in the ATP synthase subunit 6 gene of the mtDNA show a more even tissue distribution and do not appear to change significantly over time. There are only few reports of prenatal diagnosis of the T8993G mutation in Leigh disease. Here we describe the first prenatal genetic testing of T8993C in a fetus of a mother whose previous child had died of Leigh syndrome due to the T8993C mutation. Mutant load in the chorionic villus sample (CVS) as well as in amniocytes was undetectable, thus predicting a very high likelihood of an unaffected outcome, indicative of a healthy baby. The diagnosis was confirmed after birth. Gathering data on the prenatal diagnosis of mtDNA mutations is of great importance so that prenatal diagnosis of both T8993G and T8993C mutations can be offered routinely. Copyright © 2002 John Wiley & Sons, Ltd.     

Photocatalytic reduction of carbon dioxide over Cu/TiO<Subscript>2</Subscript> photocatalysts

The photocatalytic reduction of CO₂ with H₂O was investigated using Cu/TiO₂ photocatalysts in aqueous solution. For this purpose, Cu/TiO₂ photocatalysts (with 0.2, 0.9, 2, 4, and 6 wt.% of Cu) have been synthesized via sol-gel method. The photocatalysts were extensively characterized by means of inductively coupled plasma optical emission spectrometry (ICP-OES), N₂ physisorption (BET), XRD, UV-vis DRS, FT-IR, Raman spectroscopy, TEM-EDX, and photoelectrochemical measurements. The as-prepared photocatalysts contain anatase as a major crystalline phase with a crystallite size around 13 nm. By increasing the amount of Cu, specific surface area and band gap energy decreased in addition to the formation of large agglomeration of CuO. Results revealed that the photocatalytic reduction of CO₂ decreased in the presence of Cu/TiO₂ in comparison to pure TiO₂, which might be associated to the formation of CuO phase acting as a recombination center of generated electron-hole pair. Decreasing of photoactivity can also be connected with a very low position of conduction band of photocatalysts with high Cu content, which makes H₂ production necessary for CO₂ reduction more difficult.     

The use of imaging technology in the assessment of the fetal inflammatory response syndrome—imaging of the fetal thymus

The fetal inflammatory response syndrome (FIRS) describes a state of extensive fetal multi organ involvement during chorioamnionitis, and is associated with grave implications on perinatal outcome. The syndrome has been linked to the preterm parturition syndrome and is associated with inflammation/infection processes in most of the fetal organs. The fetal thymus, a major organ in the developing immune system involutes during severe neonatal disease and has been shown to be smaller in fetuses with FIRS. Various methods for imaging of the fetal thymus and measurement are described. Currently the only method to diagnose FIRS prenatally is through amniocentesis. We suggest that women who are admitted with preterm labor with intact membranes and those with PPROM should have a detailed sonographic examination of the fetal thymus as a surrogate marker of fetal involvement in intrauterine infection/inflammation processes. © 2015 John Wiley & Sons, Ltd.     

如何在教学中做到“到位而不越位”——针对中年段语文教学的研讨

<正>中年级的语文阅读教学,既要完成本学段的学习目标,又要为高年级的阅读教学作准备,起着承上启下的作用,是学生语文学习的一个重要阶段。但是纵观中年段的语文课文安排,我们不难发现:有一些是原老教材的高年级课文,移到了中年级,如《太阳》《小英雄雨来》《西门豹》《一个中国孩子的呼声》等。这些文章篇幅长、内容深,对于中年级孩     

Photocatalytic decomposition of N<Subscript>2</Subscript>O over g-C<Subscript>3</Subscript>N<Subscript>4</Subscript>/WO<Subscript>3</Subscript> photocatalysts

Although the nitrous oxide belongs among three of the most contributing greenhouse gases to global warming, it is quite neglected by photocatalytic society. The g-C₃N₄ and WO₃ composites were therefore tested for the photocatalytic decomposition of N₂O for the first time. The pure photocatalysts were prepared by simple calcination of precursors, and the composites were prepared by mixing of suspension of pure components in water followed by calcination. The structural (X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy), textural (N₂ physisorption), and optical properties (diffuse reflectance spectroscopy, photoluminescence spectroscopy, photoelectrochemical measurements) of all composites were correlated with photocatalytic activity. The experimental results and results from characterization techniques confirmed creation of Z-scheme in the WO₃/g-C₃N₄ composites, which was confirmed by hydroxyl radicals’ trapping measurements. The photocatalytic decomposition of N₂O was carried out in the presence of UVA light (peak intensity at 365 nm) and the 1:2 WO₃/g-C₃N₄ composite was the most active one, but the photocatalytic activity was just negligibly higher than that of pure WO₃. This is caused by relatively weak interaction between WO₃ and g-C₃N₄ which was revealed from XPS.     

Trace elements in size-segregated urban aerosol in relation to the anthropogenic emission sources and the resuspension

Size segregated particulate samples of atmospheric aerosols in urban site of continental part of Balkans were collected during 6 months in 2008. Six stages impactor in the size ranges: Dp?≤?0.49 μm, 0.49?2?≈?30 %) followed by traffic (PC2, σ²?≈?20 %) that are together contributing around 50 % of elements in the investigated urban aerosol. The EF model shows that major origin of Cd, K, V, Ni, Cu, Pb, Zn, and As in the fine mode is from the anthropogenic sources while increase of their contents in the coarse particles indicates their deposition from the atmosphere and soil contamination. This approach is useful for the assessment of the local resuspension influence on element’s contents in the aerosol and also for the evaluation of the historical pollution of soil caused by deposition of metals from the atmosphere.