Nonspecific Effect of Stress on Brain Gray Matter Volume in Drug-naive Female Patients with First Depressive Episode / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>This study aimed to observe the differences in brain gray matter volume in drug-naive female patients after the first episode of major depression with and without stressful life events (SLEs) before the onset of depression.</p><p><b>METHODS</b>Forty-three drug-naive female patients voluntarily participated in the present study after the first major depressive episode. The life event scale was used to evaluate the severity of the impact of SLEs during 6 months before the onset of the major depressive episode. High-field magnetic resonance imaging (MRI) scans were obtained, and the VBM and SPM8 software process were used to process and analyze the MRI.</p><p><b>RESULTS</b>Compared to that in patients without SLEs, the volume of brain gray matter was lower in the bilateral temporal lobe, right occipital lobe, and right limbic lobe in the SLE group. However, the gray matter volume did not differ significantly between the two groups after the application of false discovery rate (FDR) correction.</p><p><b>CONCLUSIONS</b>Although the results of the present study suggest the absence of significant differences in brain gray matter volume between female drug-naive patients after the first episode of major depression with and without SLEs after FDR correction, the study provides useful information for exploring the definitive role of stress in the onset of depression.</p>

The effect of bone marrow mesenchymal stem cell transplantation on hypoxic pulmonary hypertension in rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the influence of bone marrow mesenchymal stem cells (MSCs) transplantation on hypoxic pulmonary hypertension (HPH) in rats.</p><p><b>METHODS</b>SD rats MSCs were separated, cultivated, identified and labeled by the green fluorescence protein (GFP) gene virus and transplanted in vitro. Healthy male SD rats were randomly divided into four groups: Normal control group (NC group) and HPH group (eight rats respectively), HPH+ MSCs transplantation group and HPH+ VEGF+ MSCs transplantation group (twenty-four respectively). The test employed atmospheric intermittent low oxygen method to establish the rat model of pulmonary hypertension and stem cells were transferred and transplanted. The rats' mean pulmonary artery pressure (mPAP) was observed; right ventricular hypertrophy index (RVHI) was calculated; the morphological change of lung small artery in various groups of rats was observed under the microscope; the distribution of lung small artery and adenovirus transfection fluorescently labeled MSCs was observed under a fluorescent microscope after 7, 14 and 28 days when stem cell was transplanted.</p><p><b>RESULTS</b>For NC group, the mPAP (mmHg) was 15.5 +/- 1.5 after twenty-eight days while the mPAPs for HPH , MSCs and MSCs+ VEGF were 26.1 +/- 1.9, 21.6 +/- 2.7 and 20.1 +/- 2.9 respectively which were apparently higher than that of NC group (P < 0.01) and compared with HPH group (P < 0.01), which declined clearly. There was no significant difference between MSCs and MSCs+ VEGF. After twenty-eight days, RVHI for NC group was 0.28 +/- 0.02 while the RVHI for HPH, MSCs and MSCs + VEGF were 0.43 +/- 0.07, 0.34 +/- 0.03 and 0.35 +/- 0.01 respectively which was apparently higher than that of NC group (P < 0.01) but which was clearly lower than that of MSCs and MSCs+ VEGF (P < 0.05) and there was no significant difference between MSCs and MSCs + VEGF. For HPH group, pulmonary arteriole wall became apparently thicker, the lumen became significantly narrow and nearly obstructed after twenty-eight days, the endothelial cells were incomplete; compared with HPH group, pulmonary arteriole wall of MSCs group became thin, the lumen was smooth and the completeness of endothelial cells was improved. Whereas for MSCs and MSCs + VEGF, these changes were not significantly clear.</p><p><b>CONCLUSION</b>After MSCs transplantation, mPAP and RVHI decline sharply and lung small artery remodeling is improved which partially reverses HPH process; there is no significant difference between VEGF together with MSCs transplantation group and pure MSCs.</p>

A water-fat separation imaging method for the brain on low field magnetic resonance imaging / 西安交通大学学报·英文版

Water-fat separation is a particularly important problem for magnetic resonance imaging. Although many methods have been proposed, the reliability is still challenging. In this work, we have presented a method based on the combination of the branch-cut method and multigrid algorithm to get a more robust performance of water-fat separation. First, the branch-cut method is applied to identify residues, which violates the requirement that the interacting phase gradient around a closed path be zero. Residues and branches are marked to be zeros and filled to the weighting factor array. Then, the unwrapped phase array can be given by the multigrid algorithm. Finally, the Dixon method for water-fat separation is applied to the unwrapped phase array. Experiments for brain scanning on the 0.3T low field MRI system demonstrate the successful application of the proposed method.