Brain volumetric MRI study of extremely low gestational age newborns (ELGANs) at 9 to 10 years of age

PURPOSE: Extremely low gestation age newborns (ELGANs) are at high risk for developmental brain abnormalities, which can lead to cognitive, physical, emotional and behavioral deficits. This study is to determine potential brain volumetric abnormalities of ELGAN children at 9 to 10 years of age. METHODS: High-resolution magnetic resonance imaging (MRI) scans were obtained from 82 ELGAN children using a dual-echo turbo spin-echo (DE-TSE) pulse sequence at 3.0T (or 1.5T at only one site). The DICOM MR images were processed with quantitative MRI algorithms programmed in Mathcad. The brain gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) volumes were quantified using semi-automated clustering segmentation algorithms. RESULTS: Total brain volumes (GM+WM) of ELGAN children showed a large distribution range from 400 to 1500 mL. About 63% of the children had smaller brain volumes while 5% of them had larger brain volumes compared to the published data from normal children at the same ages1. Smaller brain volumes were observed more often in males (74%) than in females (50%). WM reduction was the major change in ELGANs with over 90% of them (86% of males and 92% of females) having reduced WM volumes. GM volumes were either reduced (15%) or enlarged (32%); GM reduction was observed more often in males (31%) than in females (4.8%), while GM enlargement was more frequently observed in females (35%) than in males (28%). Intracranial CSF volumes range from 25 mL to 600 mL, with 16% of ELGAN children (9% of males and 21% of females) having smaller CSF volume, while 38% of them (53% of males and 27% of females) having larger CSF volume. Correlation analysis revealed a positive correlation between total intracranial matter (ICM) and CSF volumes (male: r = 0.4972, p = 0.0014 and female: r = 0.3233, p = 0.0125), but a negative correlation was found between brain volumes and CSF volumes (male: r = - 0.2998, p = 0.0424 and female: r = - 0.2279, p = 0.0596). Further analysis demonstrated a negative correlation between GM and CSF both in absolute (male: r = - 0.4489, p = 0.0039 and female: r = - 0.3769, p = 0.0041) and in relative (male: r = - 0.8675, p = 0.0000 and female: r = - 0.8350, p = 0.0000) volumes, while WM volumes did not correlate with CSF volumes. CONCLUSION: ELGAN children had mostly smaller brain volumes while some of them displayed larger brain volumes at ages of 9 to 10 years. The reduction of WM was a characteristic change in ELGAN children and contributed to smaller brain volumes. GM volumes either increased or decreased. Larger intracranial CSF volumes were associated with larger intracranial matter (ICM) volume

Rapeseed oil fortified with micronutrients reduces atherosclerosis risk factors in rats fed a high-fat diet

<p>Abstract</p> <p>Background</p> <p>Micronutrients polyphenols, tocopherols and phytosterols in rapeseed exert potential benefit to cardiovascular system, but most of these micronutrients are removed by the refining process. The aim of this study was to determine the effect of rapeseed oil fortified with these micronutrients on the atherosclerosis risk factors in rats fed a high-fat diet.</p> <p>Methods</p> <p>The rodent diet contained 20% fat whose source was refined rapeseed oil (RRO) or fortified refined rapeseed oil with low, middle and high quantities of these micronutrients (L-, M- and H-FRRO). Forty male SD rats were divided into four groups. One group received RRO diet and other groups received L-, M- and H-FRRO diet for 10 weeks.</p> <p>Results</p> <p>Micronutrients supplementation significantly increased plasma antioxidant defense capacities, as evaluated by the significant elevation in the activities of GPx, CAT and SOD as well as the level of GSH, and the significant decline in lipid peroxidation. These micronutrients also reduced the plasma contents of TG, TC and LDL-C and increased the ratio of HDL-C/LDL-C. In addition, in parallel with the enhancement of these micronutrients, plasma levels of IL-6 and CRP declined remarkably.</p> <p>Conclusion</p> <p>Rapeseed oil fortified with micronutrients polyphenols, tocopherols and phytosterols may contribute to prevent atherogenesis by ameliorating plasma oxidative stress, lipid profile and inflammation.</p

Biointerface topography regulates phenotypic switching and cell apoptosis in vascular smooth muscle cells

Background: In-stent restenosis (ISR) is a complex disease that occurs after coronary stenting procedures. The development of quality materials and improvement of our understanding on significant factors regulating ISR are essential for enhancing prognosis. Vascular smooth muscle cells (VSMCs) are the main constituent cells of blood vessel walls, and dysfunction of VMSCs can exacerbate ISR. Accordingly, in this study, we explored the influence of wrinkled material topography on the biological functions of VSMCs. Methods: Polydimethylsiloxane with a wrinkled topography was synthesized using elastomer base and crosslinking and observed by atomic force microscopy. VSMC proliferation, apoptosis, and morphology were determined by Cell Counting Kit-8 assays, fluorescence-assisted cell sorting, and phalloidin staining. α-Smooth muscle actin (α-SMA), major histocompatibility complex (MHC), and calponin 1 (CNN-1) expression levels were measured by quantitative real-time polymerase chain reaction and western blotting. Moreover, p53 and cleaved caspase-3 expression levels were evaluated by western blotting in VSMCs to assess apoptotic induction. Results: Surface topographies were not associated with a clear orientation or elongation of VSMCs. The number of cells was increased on wrinkled surfaces (0.7 μm in amplitude, and 3 μm in wavelength [W3]) compared with that on other surfaces, contributing to continuously increased cell proliferation. Moreover, interactions of VSMCs with the W3 surface suppressed phenotypic switching, resulting in ISR via regulation of α-SMA, calponin-1, and SM-MHC expression. The surface with an amplitude of 0.05 μm and a wavelength of 0.5 μm (W0.5) promoted apoptosis by inducing caspase 3 and p53 activities. Conclusion: Introduction of aligned topographies on biomaterial scaffolds could provide physical cues to modulate VSMC responses for engineering vascular constructs. Materials with wrinkled topographies could have applications in the development of stents to reduce ISR

Rhodapentalenes: Pincer Complexes with Internal Aromaticity

Summary(#br)Pincer complexes are a remarkably versatile family benefited from their stability, diversity, and tunability. Many of them contain aromatic organic rings at the periphery, and aromaticity plays an important role in their stability and properties, whereas their metallacyclic cores are not aromatic. Herein, we report rhodapentalenes, which can be viewed as pincer complexes in which the metallacyclic cores exhibit considerable aromatic character. Rhodapentalenes show good thermal stability, although the rhodium-carbon bonds in such compounds are fragile. Experimental and computational studies suggest that the stabilization of rigid CCC pincer architectures together with an intrinsic aromaticity is vital for these metallacyclic rhodium species. Dearomatization-aromatization reactions, corresponding to metal-ligand cooperation of classical aromatic pincer complexes, were observed in this system. These findings suggest a new concept for pincer chemistry, the internal aromaticity involving metal d -orbitals, which would be useful for exploiting the nature of construction motif and inspire further applications

Rhodapentalenes: Pincer Complexes with Internal Aromaticity.

Pincer complexes are a remarkably versatile family benefited from their stability, diversity, and tunability. Many of them contain aromatic organic rings at the periphery, and aromaticity plays an important role in their stability and properties, whereas their metallacyclic cores are not aromatic. Herein, we report rhodapentalenes, which can be viewed as pincer complexes in which the metallacyclic cores exhibit considerable aromatic character. Rhodapentalenes show good thermal stability, although the rhodium-carbon bonds in such compounds are fragile. Experimental and computational studies suggest that the stabilization of rigid CCC pincer architectures together with an intrinsic aromaticity is vital for these metallacyclic rhodium species. Dearomatization-aromatization reactions, corresponding to metal-ligand cooperation of classical aromatic pincer complexes, were observed in this system. These findings suggest a new concept for pincer chemistry, the internal aromaticity involving metal d-orbitals, which would be useful for exploiting the nature of construction motif and inspire further applications

Constraint of a ruthenium-carbon triple bond to a five-membered ring

含过渡金属碳三键(M≡C)的金属卡拜化合物是许多有机反应的催化剂或关键中间体。对其合成及性质的研究是金属有机化学的热点之一。由于卡拜碳的sp杂化方式，大部分金属卡拜化合物均为链状结构（卡拜碳键角理想值为180 °），环内金属卡拜化合物因存在很大的环张力而难于合成。夏海平教授课题组发展了由链状多炔（称之为碳龙）构筑碳龙配合物的高效方法（Nature Communications, 2017, 8, 1912），实现了锇杂戊搭炔/烯及其衍生物的一锅法合成。现在，他们把该方法进一步拓展到了第二过渡系金属钌，通过碳龙与市售的RuCl2(PPh3)3反应一锅合成了钌杂戊搭炔I。本研究是碳龙化学的进一步延伸和发展，首次把碳龙化学的金属中心由锇拓展到了其它金属，展示了碳龙化学广阔的发展空间。该研究工作在夏海平教授指导下完成，能源材料化学协同创新中心（iChEM）博士后卓庆德和张弘副教授为共同第一作者。iChEM博士后周小茜、博士生陈志昕、林剑锋、卓凯玥、硕士康慧君、林鑫磊参与了部分实验工作。博士生华煜晖负责理论计算。【Abstract】The incorporation of a metal-carbon triple bond into a ring system is challenging because of the linear nature of triple bonds. To date, the synthesis of these complexes has been limited to those containing third-row transition metal centers, namely, osmium and rhenium. We report the synthesis and full characterization of the first cyclic metal carbyne complex with a second-row transition metal center, ruthenapentalyne. It shows a bond angle of 130.2(3)° around the sp-hybridized carbyne carbon, which represents the recorded smallest angle of second-row transition metal carbyne complexes, as it deviates nearly 50° from the original angle (180°). Density functional theory calculations suggest that the inherent aromatic nature of these metallacycles with bent Ru≡C–C moieties enhances their stability. Reactivity studies showed striking observations, such as ambiphilic reactivity, a metal-carbon triple bond shift, and a [2 + 2] cycloaddition reaction with alkyne and cascade cyclization reactions with ambident nucleophiles.This research was supported by the National Key R&D Program of China (2017YFA0204902) and the National Natural Science Foundation of China (nos. 21490573,21332002, and 21561162001). 研究工作得到国家自然科学基金项目（21490573、21332002 和21561162001）和国家重点研发计划（2017YFA0204902）的资助

Reactions of Osmium Hydrido Alkenylcarbyne with Allenoates: Insertion and [3+2] Annulation

通讯作者地址: Zhang, HTreatment of the osmium hydrido alkenylcarbyne complex [OsH{equivalent to CC(PPh3)=CHPh}(PPh3)(2)Cl-2]BF4 (1) with allenoates (CH2=C=CHCOOR, R = Me, Et) in the presence of excess AgBF4 leads to the insertion products 2/3. The reactions of complex 1 with substituted allenoates, i.e., diethyl 2-vinylidenesuccinate (CH2=C=C(CH2COOEt)(COOEt)) and ethyl penta-2,3-dienoate (CH(CH3)=C=CH(COOEt)), result in the formation of [3 + 2] annulation products 4 and 6, respectively. Mechanisms of the reactions have been proposed with the isolation of the key intermediates. The results reveal that the divergent pathways for these reactions are mainly of steric origin.National Natural Science Foundation of China 21272193 21332002 21490573 program for Changjiang Scholars and Innovative Research Team in Universit