CryoAlign: feature-based method for global and local 3D alignment of EM density maps

Advances on cryo-electron imaging technologies have led to a rapidly increasing number of density maps. Alignment and comparison of density maps play a crucial role in interpreting structural information, such as conformational heterogeneity analysis using global alignment and atomic model assembly through local alignment. Here, we propose a fast and accurate global and local cryo-electron microscopy density map alignment method CryoAlign, which leverages local density feature descriptors to capture spatial structure similarities. CryoAlign is the first feature-based EM map alignment tool, in which the employment of feature-based architecture enables the rapid establishment of point pair correspondences and robust estimation of alignment parameters. Extensive experimental evaluations demonstrate the superiority of CryoAlign over the existing methods in both alignment accuracy and speed

Sex Differences in Clinical Characteristics and Brain MRI Change in Patients With Wilson’s Disease in a Chinese Population

Background: Wilson’s disease (WD) is an inborn copper metabolism disease. Sex differences in clinical features of WD patients have been reported; however, the effect of sex on brain MRI is still unclear, especially for Chinese WD patients. Therefore, we aimed to examine sex differences in clinical correlates and brain MRI changes in WD patients in a Chinese Han population.Methods: 535 WD patients were enrolled and underwent MRI scanning. These patients were subdivided by the clinical symptoms, Kayser–Fleischer (K–F) rings, laboratory tests and sex. The mean age of onset and diagnosis, disease latency, localization of brain MRI lesions, and the level of copper metabolism were compared between male and female patients.Results: The neuropsychiatric form (452 and 84.5%) was the most common subtype. Compared to female patients, male patients had a higher percentage in three clinical forms: neuropsychiatric form (263 and 58.2%), hepatic form (41 and 59.4%), and presymptomatic form (10 and 71.4%). In the neuropsychiatric form, male patients had the earlier age of onset and definitive diagnosis, and shorter time of disease latency than female patients. Putamen was the most common site for lesions in brain MRI of three groups. In the hepatic form, more male patients showed the ventricular widening than female patients (14/41 vs. 3/28; p < 0.05). The level of serum ceruloplasmin and copper of WD patients with neuropsychiatric form was higher than that of male patients with hepatic or presymptomatic form. In women, however, patients of presymptomatic form have the highest level of the ceruloplasmin, and the level of serum copper in hepatic patients was highest.Conclusion: Our findings suggest sex differences in the percentage of three clinical forms. Meanwhile, the mean age of onset and diagnosis of female was higher than male, also happened in the disease latency. Only in the hepatic form, there was a sex difference in the ventricular widening

Environmental impact assessments of the Three Gorges Project in China: issues and interventions

The paper takes China's authoritative Environmental Impact Statement for the Yangzi (Yangtze) Three Gorges Project (TGP) in 1992 as a benchmark against which to evaluate emerging major environmental outcomes since the initial impoundment of the Three Gorges reservoir in 2003. The paper particularly examines five crucial environmental aspects and associated causal factors. The five domains include human resettlement and the carrying capacity of local environments (especially land), water quality, reservoir sedimentation and downstream riverbed erosion, soil erosion, and seismic activity and geological hazards. Lessons from the environmental impact assessments of the TGP are: (1) hydro project planning needs to take place at a broader scale, and a strategic environmental assessment at a broader scale is necessary in advance of individual environmental impact assessments; (2) national policy and planning adjustments need to react quickly to the impact changes of large projects; (3) long-term environmental monitoring systems and joint operations with other large projects in the upstream areas of a river basin should be established, and the cross-impacts of climate change on projects and possible impacts of projects on regional or local climate considered. © 2013 Elsevier B.V.Xibao Xu, Yan Tan, Guishan Yan

Susceptibility-Weighted Imaging Manifestations in the Brain of Wilson's Disease Patients.

It is well known that patients with Wilson's disease (WD) suffer copper metabolism disorder. However, recent studies point to an additional iron metabolism disorder in WD patients. The purpose of our study was to examine susceptibility-weighted imaging (SWI) manifestations of WD in the brains of WD patients.A total of 33 patients with WD and 18 normal controls underwent conventional MRI (Magnetic resonance imaging) and SWI. The phase values were measured on SWI-filtered phase images of the bilateral head of the caudate nuclei, globus pallidus, putamen, thalamus, substantia nigra, and red nucleus. Student's t-tests were used to compare the phase values between WD groups and normal controls.The mean phase values for the bilateral head of the caudate nuclei, globus pallidus, putamen, thalamus, substantia nigra, and red nucleus were significantly lower than those in the control group (P < 0.001), and bilateral putamen was most strongly affected.There is paramagnetic mineralization deposition in brain gray nuclei of WD patients and SWI is an effective method to evaluate these structures

Accurate global and local 3D alignment of cryo-EM density maps using local spatial structural features

Abstract Advances in cryo-electron microscopy (cryo-EM) imaging technologies have led to a rapidly increasing number of cryo-EM density maps. Alignment and comparison of density maps play a crucial role in interpreting structural information, such as conformational heterogeneity analysis using global alignment and atomic model assembly through local alignment. Here, we present a fast and accurate global and local cryo-EM density map alignment method called CryoAlign, that leverages local density feature descriptors to capture spatial structure similarities. CryoAlign is a feature-based cryo-EM map alignment tool, in which the employment of feature-based architecture enables the rapid establishment of point pair correspondences and robust estimation of alignment parameters. Extensive experimental evaluations demonstrate the superiority of CryoAlign over the existing methods in terms of both alignment accuracy and speed

Neuron-Glial Antigen 2 Participates in Liver Fibrosis via Regulating the Differentiation of Bone Marrow Mesenchymal Stem Cell to Myofibroblast

Neuron-glial antigen 2 (NG2, gene name: Cspg4) has been characterized as an important factor in many diseases. However, the pathophysiological relevance of NG2 in liver disease specifically regarding bone marrow mesenchymal stem cell (BMSC) differentiation to myofibroblast (MF) and the molecular details remain unknown. Human liver tissues were obtained from patients with different chronic liver diseases, and mouse liver injury models were induced by feeding a methionine-choline-deficient and high-fat diet, carbon tetrachloride administration, or bile duct ligation operation. NG2 expression was increased in human and mouse fibrotic liver and positively correlated with MF markers α-smooth muscle actin (αSMA) and other fibrotic markers in the liver. There was a co-localization between NG2 and αSMA, NG2 and EGFP (BMSC-derived MF) in the fibrotic liver determined by immunofluorescence analysis. In vitro, TGFβ1-treated BMSC showed a progressive increase in NG2 levels, which were mainly expressed on the membrane surface. Interestingly, there was a translocation of NG2 from the cell membrane into cytoplasm after the transfection of Cspg4 siRNA in TGFβ1-treated BMSC. siRNA-mediated inhibition of Cspg4 abrogated the TGFβ1-induced BMSC differentiation to MF. Importantly, inhibition of NG2 in vivo significantly attenuated the extent of liver fibrosis in methionine-choline-deficient and high fat (MCDHF) mice, as demonstrated by the decreased mRNA expression of fibrotic parameters, collagen deposition, serum transaminase levels, liver steatosis and inflammation after the administration of Cspg4 siRNA in MCDHF mice. We identify the positive regulation of NG2 in BMSC differentiation to MF during liver fibrosis, which may provide a promising target for the treatment of liver disease

Metabolic abnormalities in adolescents with polycystic ovary syndrome in south china

<p>Abstract</p> <p>Background</p> <p>Adults with polycystic ovary syndrome (PCOS) can have multiple metabolic abnormalities. However, studies in the adolescent population are still limited and these results seem to vary widely. This study was to investigate the metabolic abnormalities in adolescents with PCOS in South China and the potential risk factors contributed to these health risks.</p> <p>Methods</p> <p>Anthropometric measurements and biochemical parameters were evaluated in 128 adolescents with PCOS and their age- and BMI-matched controls.</p> <p>Results</p> <p>The prevalence of pre-diabetes, insulin resistance, hyperinsulinemia, dyslipidemia and metabolic syndrome in adolescents with PCOS was 11.7%, 46.9%, 29.7%, 22.7% and 4.7%, respectively. 16.3%, 74.4%, 67.4%, 39.5% and 14% of the PCOS subjects with BMI > 85th had pre-diabetes, insulin resistance, hyperinsulinemia, dyslipidemia and metabolic syndrome, whereas 9.4%, 32.9%, 10.6%, 14.1% and 0% of the PCOS subjects with BMI < 85th had such disturbances.</p> <p>Conclusions</p> <p>Adolescents with PCOS in South China had more metabolic abnormalities than their age- and BMI-matched non-PCOS counterparts. Obesity could worsen insulin resistance, hyperinsulinemia and metabolic syndrome in PCOS adolescents.</p

OCT-Precoding Combined with LDPC-Coding Scheme for 128 QAM MB-OFDM UWBoF System

In this paper, we proposed a coding scheme based on orthogonal cyclic transpose (OCT) precoding combined with low-density parity check (LDPC) code to improve the transmission performance of 128-quadrature amplitude modulation multiband orthogonal-frequency-division-multiplexing ultrawide band over fiber (128 QAM MB-OFDM UWBoF) system. The proposed scheme could not only improve the performance of the system but also average the signal-to-noise ratio (SNR) of subcarriers and reduce the difference among subchannels in practical application. The simulation results showed that compared with the traditional scheme, the receiver performance of this scheme was improved by 2.7 dB when the LDPC-coding rate was 87.5% through 70 km standard single mode fiber (SSMF) transmission and the bit error rate (BER) was 3.8 × 10−3. Besides, the constellation distribution was more convergent and uniform