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341.
Guiling Ma Yanfang Li Juan Zhang Hao Liu Dongyan Hou Lei Zhu Zhenyu Zhang Lin Zhang 《PloS one》2013,8(3)
Background
Pre-eclampsia is the leading cause of maternal and neonatal morbidity and mortality with incompletely understood etiopathogenesis. The purpose of the current study is to determine whether there is a relationship between the presence of autoantibodies against β1, β2 and α1 adrenoreceptors and severe pre-eclampsia.Methodology/Principal Findings
Synthetic peptides corresponding to amino acid sequences of the second extracellular loops of β1, β2 and α1 adrenoreceptors were synthesized as antigens to test 34 patients with severe pre-eclampsia, 36 normal pregnancy women and 40 non-pregnant controls for the presence of autoantibodies using enzyme-linked immunosorbent assay. The respective frequencies of autoantibodies against β1, β2 and α1 adrenoreceptors were 50.0% (17/34), 52.9% (18/34) and 55.9% (19/34) in patients with severe pre-eclampsia, 19.4% (7/36) (p = 0.011), 19.4% (7/36) (p = 0.006) and 17.6% (6/36) (p = 0.001) in normal pregnancy women and 10% (4/40), 7.5% (3/40) and 10% (4/40) (p<0.001) in non-pregnant controls. Titers of these autoantibodies were also significantly increased in patients with severe pre-eclampsia. By logistic regression analysis, the presence of these three autoantibodies significantly increased the risk of neonatal death (odds ratio, 13.5; 95% confidence interval, 1.3–141.3; p = 0.030) and long-term neonatal hospitalization (odds ratio, 5.0; 95% confidence interval, 1.3–19.1; p = 0.018). The risk of hypertension and fetal distress were also associated with the presence of these three autoantibodies.Conclusions/Significance
This novel pilot study demonstrated for the first time that the presence of autoantibodies against β1, β2 and α1 adrenoreceptors are increased in patients with severe pre-eclampsia. Pregnant women who are positive for the three autoantibodies are at increased risks of neonatal mortality and morbidity. We posit that these autoantibodies may be involved in the pathogenesis of severe pre-eclampsia. 相似文献342.
Background
Expanded criteria donors (ECDs) are currently accepted as potential sources to increase the donor pool and to provide more chances of kidney transplantation for elderly recipients who would not survive long waiting periods. Hypothermic machine perfusion (HMP) is designed to mitigate the deleterious effects of simple cold storage (CS) on the quality of preserved organs, particularly when the donor is in a marginal status.Methods
We compared the transplant outcomes in patients receiving ECD kidneys with either HMP or CS graft preservation. Articles from the MEDLINE, EMBASE and Cochrane Library databases were searched and all studies reporting outcomes from HMP versus CS methods of kidney preservation were included in this meta-analysis. The parameters analyzed included the incidence of delayed graft function (DGF), primary non-function (PNF) and one-year graft and patient survival.Results
A total of seven studies qualified for the review, involving 2374 and 8716 kidney grafts with HMP or CS preservation respectively, all from ECD donors. The incidence of delayed graft function (DGF) was significantly reduced with an odd ratio(OR) of 0.59 (95% CI 0.54–0.66, P<0.001) and one-year graft survival was significantly improved with an OR of 1.12 (95% CI 1.03–1.21, P = 0.005) in HMP preservation compared to CS. However, there was no difference in the incidence of PNF (OR 0.54, 95% CI 0.21–1.40, P = 0.20), and one-year patient survival (OR 0.98, 95% CI 0.94–1.02, P = 0.36) between HMP and CS preservation.Conclusions
HMP was associated with a reduced incidence of DGF and an with increased one-year graft survival, but it was not associated with the incidence of PNF and one-year patient survival. 相似文献343.
Yu Chen Huadan Xue Zheng-yu Jin Jie Zhang Hao Sun Xuan Wang Zhu-hua Zhang Da-ming Zhang Guang-ming Lu Zhao-qi Zhang U. Joseph Schoepf Andreas M. Bucher Christopher D. Wolla Yun Wang 《PloS one》2013,8(11)
Background
Our study aims to evaluate the image quality and feasibility of 128-slice dual-energy CTA (DE-CTA) for supra-aortic arteries using reduced amounts of contrast medium (CM).Methods
A prospective study was performed in 54 patients receiving CTA of the head and neck with a 128-slice dual-source CT system. Patients were randomized into two groups with a volume of either 40 mL of CM (Group I) or 50 mL of CM (Group II). Arterial and venous enhancements were recorded for quantitative assessment. Qualitative assessments for images without bone removal (BR) were based on a) the visualization of the circle of Willis and b) streak artifacts due to residual CM in the subclavian or internal jugular veins ipsilateral to injection of CM. Qualitative assessment of dual-energy images using BR was based on the presence of bone remnants and vessel integrity. Quantitative data was compared using the Student t test. The χ2 test was used for the qualitative measurements of streak artifacts in veins while the Mann-Whitney U test was used for the qualitative measurements of images with BR.Results
Arterial and venous attenuation was significantly higher in Group II (P=0.000). Image quality regarding the circle of Willis was excellent in both groups (3.90±0.30 for Group I and 4.00±0 for Group II) . Imaging of the internal jugular veins was scored higher in Group I (1.87±0.72) compared with Group II (1.48±0.51) (P=0.021). Within Group I using BR, mean scores for bone remnants did not differ significantly (P>0.05) but mean scores of vessel integrity (P<0.05) did.Conclusions
Contrast-enhanced head and neck CTA is feasible using a scan protocol with low amounts of contrast medium (40 mL) on a 128-slice dual-energy CTA. The 40-mL protocol provides satisfactory image quality before and after dual-energy bone-removal post-processing. 相似文献344.
Xiao Sun Wen Zhou Hao Liu Aijun Zhang Chao-Ren Ai Shuang-Shuang Zhou Chang-Xiang Zhou Man-Qun Wang 《PloS one》2013,8(11)
Background
Transgenic Bt rice line T2A-1 expresses a synthesized cry2A gene that shows high resistance to Lepidoptera pests, including Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Pyralidae). Plant volatile orientation cues and the physical characteristics of the leaf surface play key roles in host location or host-plant acceptance of phytophagous insects. These volatile compounds and physical traits may become altered in Bt rice and it is not known whether this influences the behavior of C. medinalis when searching for oviposition sites.Results
The results of electronic nose analysis showed that the Radar map of Bt rice cultivars was analogous to the non- Bt rice cultivars at each growing stage. PCA analysis was able to partly discriminate between some of the Bt vs. non-Bt rice sensors, but could not to separate Bt cultivars from non-Bt cultivars. The total ion chromatogram between Bt and non-Bt rice cultivars at the seedling, booting and tillering stages were similar and 25 main compounds were identified by GC-MS. For most compounds, there was no significant difference in compound quantities between Bt and non-Bt rice cultivars at equivalent growth stages. The densities of the tubercle papicles and the trichomes on the upper and lower surfaces were statistically equal in Bt and non-Bt rice. The target pest, C. medinalis, was attracted to host rice plants, but it could not distinguish between the transgenic and the isogenic rice lines.Conclusions
There were no significant differences between the Bt rice line, T2A-1 and the non-Bt rice for volatiles produced or in its physical characteristics and there were no negative impacts on C. medinalis oviposition behavior. These results add to the mounting evidence that Bt rice has no negative impact on the target insect oviposition behavior. 相似文献345.
Jing Qian Huaizhou You Qiuyu Zhu Shuai Ma Ying Zhou Ying Zheng Junfeng Liu Dingwei Kuang Yong Gu Chuanming Hao Feng Ding 《PloS one》2013,8(11)
Background
To examine the characteristics of oxidative stress in patients with acute kidney injury (AKI) and investigate the association between plasma nitrotyrosine levels and 90-day mortality in patients with AKI.Methodology/Principal Findings
158 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. Twelve critically ill patients without AKI and 15 age and gender-matched healthy subjects served as control. Plasma 3-nitrotyrosine was analyzed in relation to 90-day all cause mortality of patients with AKI. The patients with AKI were followed up for 90 days and grouped according to median plasma 3-nitrotyrosine concentrations. Highest 3-NT/Tyr was detected in patients with AKI compared with healthy subjects, and critically ill patients without AKI (ANOVA p<0.001). The 90-day survival curves of patients with high 3-NT/Tyr showed significant differences compared with the curves of individuals with low 3-NT/Tyr (p = 0.001 by log rank test). Multivariate analysis (Cox regression) revealed that 3-NT/Tyr (p = 0.025) was independently associated with mortality after adjustment for age, gender, sepsis and Acute Physiology and Chronic Health Evaluation (APACHE) II score.Conclusions/Significance
There is excess plasma protein oxidation in patients with AKI, as evidenced by increased nitrotyrosine content. 3-NT/Tyr level was associated with mortality of AKI patients independent of the severity of illness. 相似文献346.
Huidong Li Hao Feng Weiguo Sun Qunchao Fan Yaoming Xie R. Bruce King Henry F. Schaefer III 《Journal of molecular modeling》2013,19(7):2723-2737
The bis(heptalene)dimetal complexes (C12H10)2M2 of the first row transition metals from Ti to Ni are predicted by density functional theory to exhibit “submarine” sandwich structures with a pair of metal atoms sandwiched between the two heptalene rings. For the early transition metal derivatives (C12H10)2M2 (M = V, Cr) there are two types of such structures. In one structural type the metals are sandwiched between two heptahapto heptalene rings with metal-metal distances (3.5–3.8 Å) too long for direct metal-metal bonding. The other type of (C12H10)2M2 (M = V, Cr, Mn) structure has a pair of bonded metal atoms sandwiched between a fully bonded heptalene ligand and a heptalene ligand bonded to the metals only through an eight-carbon heptafulvene subunit, leaving an uncomplexed cis-1,3-diene unit. The formal metal-metal bond orders in these latter structures are 3, 2, and 1 for M = V, Cr, and Mn with predicted bond lengths of 2.5, 2.7, and 2.8 Å, respectively. For (C12H10)2Fe2 a singlet structure with each iron atom sandwiched between a hexahapto and a tetrahapto heptalene ring is energetically preferred over an alternate structure with ferrocene-like iron atoms sandwiched between two pentahapto heptalene rings. Partial bonding of each heptalene ring to the metal atoms occurs in the late transition metal derivatives (C12H10)2M2 (M = Co, Ni). This leads to an unsymmetrical structure for the cobalt derivative and a structure for the nickel derivative with each nickel atom sandwiched between a trihapto ligand and a tetrahapto ligand. Figure
The bis(heptalene) dimetal complexes (C12H10)2M2 (M = Ti to Ni) are predicted by density functional theory to have a “submarine” sandwich structure with a pair of metal atoms sandwiched between the two heptalene rings. In the early transition metal derivatives (C12H10)2M2 (M = V, Cr) the metal atoms are sandwiched between two heptahapto heptalene rings. In contrast, for (C12H10)2M2 (M = Mn, Fe, Co, Ni) the heptalene rings are only partially bonded to the metal atoms. 相似文献
347.
The interaction between M (M?=?Ca, Yb) atom and C74 (D 3h) has been investigated by all electron relativistic density function theory. With the aid of the representative patch of C74 (D 3h), we studied the interaction between C74 (D 3h) and M (M?=?Ca, Yb) atom and obtained the interaction potential. Optimized structures show that there are three equivalent stable isomers and there is one transition state between every two stable isomers. According to the minimum energy pathway, the possible movement trajectory of M (M?=?Ca, Yb) atom in the C74 (D 3h) cage is explored. The calculated energy barrier for Yb atoms moving from the stable isomer to the transition state is 10.4 kcal mol?1 and the energy barrier for Ca atoms is 6.1 kcal mol?1. The calculated NMR spectra of M@C74 (M?=?Ca, Yb) are in good agreement with the experimental data. There are nine lines in the spectra: one 1/6 intensity signal, four half intensity signals and four full intensity signals. 相似文献
348.
Hao Chen Linfeng Hu Yan Yan Renchao Che Min Chen Limin Wu 《Liver Transplantation》2013,3(12):1636-1646
A facile one‐step hydrothermal co‐deposition method for growth of ultrathin Ni(OH)2‐MnO2 hybrid nanosheet arrays on three dimensional (3D) macroporous nickel foam is presented. Due to the highly hydrophilic and ultrathin nature of hybrid nanosheets, as well as the synergetic effects of Ni(OH)2 and MnO2, the as‐fabricated Ni(OH)2‐MnO2 hybrid electrode exhibits an ultrahigh specific capacitance of 2628 F g?1. Moreover, the asymmetric supercapacitor with the as‐obtained Ni(OH)2‐MnO2 hybrid film as the positive electrode and the reduced graphene oxide as the negative electrode has a high energy density (186 Wh kg?1 at 778 W kg?1), based on the total mass of active materials. 相似文献
349.
350.
Guang‐Ping Hao An‐Hui Lu Wei Dong Zhen‐Yu Jin Xiang‐Qian Zhang Jin‐Tao Zhang Wen‐Cui Li 《Liver Transplantation》2013,3(11):1421-1427
Sandwich‐type microporous hybrid carbon nanosheets (MHCN) consisting of graphene and microporous carbon layers are fabricated using graphene oxides as shape‐directing agent and the in‐situ formed poly(benzoxazine‐co‐resol) as carbon precursor. The reaction and condensation can be readily completed within 45 min. The obtained MHCN has a high density of accessible micropores that reside in the porous carbon with controlled thickness (e.g., 17 nm), a high surface area of 1293 m2 g?1 and a narrow pore size distribution of ca. 0.8 nm. These features allow an easy access, a rapid diffusion and a high loading of charged ions, which outperform the diffusion rate in bulk carbon and are highly efficient for an increased double‐layer capacitance. Meanwhile, the uniform graphene percolating in the interconnected MHCN forms the bulk conductive networks and their electrical conductivity can be up to 120 S m?1 at the graphene percolation threshold of 2.0 wt.%. The best‐practice two‐electrode test demonstrates that the MHCN show a gravimetric capacitance of high up to 103 F g?1 and a good energy density of ca. 22.4 Wh kg?1 at a high current density of 5 A g?1. These advanced properties ensure the MHCN a great promise as an electrode material for supercapacitors. 相似文献