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Song Z.,Xiamen University | Xu X.,Chinese Academy of Sciences | Dong J.,Chinese Academy of Sciences | Xing L.,Chinese Academy of Sciences | And 6 more authors.
Journal of the Acoustical Society of America

Computed tomography (CT) imaging and sound experimental measurements were used to reconstruct the acoustic properties (density, velocity, and impedance) of the forehead tissues of a deceased pygmy sperm whale (Kogia breviceps). The forehead was segmented along the body axis and sectioned into cross section slices, which were further cut into sample pieces for measurements. Hounsfield units (HUs) of the corresponding measured pieces were obtained from CT scans, and regression analyses were conducted to investigate the linear relationships between the tissues' HUs and velocity, and HUs and density. The distributions of the acoustic properties of the head at axial, coronal, and sagittal cross sections were reconstructed, revealing that the nasal passage system was asymmetric and the cornucopia-shaped spermaceti organ was in the right nasal passage, surrounded by tissues and airsacs. A distinct dense theca was discovered in the posterior-dorsal area of the melon, which was characterized by low velocity in the inner core and high velocity in the outer region. Statistical analyses revealed significant differences in density, velocity, and acoustic impedance between all four structures, melon, spermaceti organ, muscle, and connective tissue (p < 0.001). The obtained acoustic properties of the forehead tissues provide important information for understanding the species' bioacoustic characteristics. © 2015 Acoustical Society of America. Source

Yang L.,Lanzhou University | Li T.,Lanzhou University | Lu Y.,University of Sichuan | Luo G.,Peoples Hospital of Guizhou | And 2 more authors.
Academic Journal of Second Military Medical University

Objective To observe C4d deposition in renal allografts of rats undergoing chronic allograft nephropathy (CAN), and to analyze the effects of immunosuppressants on deposition of C4d in peritubular capillaries. Methods The renal grafts of Fisher 344 rats were ortho topically transplanted into Lewis rats to create CAN models, and all the recipients were given cyclosporine A (CsA) 10 mg/(kg · d) X10d after operation. The models were then divided into 5 groups (each n=9): Group A was normal saline control group, only receiving vehicle orally; Group B, C, D, and E received CsA 6 mg/(kg · d), RAPA0. 8 mg/(kg · d), FK506 0. 15 mg/(kg · d), and MMF 20 mg/(kg · d), respectively. The renal allografts were harvested after three rats were sacrificed at the 4th, 8th and 12th weeks post-transplantation. The histological changes were assessed according to Banff 97 standard. The deposition of C4d was detected by immunofluorescence method. Results C4d deposition in peritubular capillary (PTC) was found in all the allografts at the 4th week after transplantation, while there were no obvious clinical pathological changes of CAN in all groups, and the Banff scores were not significantly different among different groups (P > 0. 05). CAN manifestations of different degrees were observed 8 weeks after operation, with increased C4d deposition in the PTC. Severest CAN was observed at the 12th week after operation, accompanied by the most C4d deposition in the PTC. C4d deposition was positively correlated with the severity of CAN (r=0. 894, P = 0. 000). Compared with the control group, CsA and FK506 showed no significant effect on C4d deposition (P>0. 05); however, MMF and RAPA significantly decreasedC4d deposition (P<0. 05). Conclusion Deposition of C4d in PTC may appear in allografts earlier than the pathological changes of CAN, and the deposition is associated with the progression of CAN. MMF and RAPA can inhibit the progression of CAN, while CsA and FK506 can not. Source

Gu S.,Wright State University | Gu S.,Hainan Medical College | Zhang W.,Peoples Hospital of Sanya | Chen J.,Wright State University | And 7 more authors.

Cell-released microvesicles (MVs) represent a novel way of cell-to-cell communication. Previous evidence indicates that endothelial progenitor cells (EPCs)-derived MVs can modulate endothelial cell survival and proliferation. In this study, we evaluated whether EPC-MVs protect cardiomyocytes (CMs) against angiotensin II (Ang II)-induced hypertrophy and apoptosis. The H9c2 CMs were exposed to Ang II in the presence or absence of EPC-MVs. Cell viability, apoptosis, surface area and β-myosin heavy chain (β-MHC) expression were analyzed. Meanwhile, reactive oxygen species (ROS), serine/threonine kinase (Akt), endothelial nitric oxide synthase (eNOS), and their phosphorylated proteins (p-Akt, p-eNOS) were measured. Phosphatidylinositol-3-kinase (PI3K) and NOS inhibitors were used for pathway verification. The role of MVcarried RNAs in mediating these effects was also explored. Results showed 1) EPC-MVs were able to protect CMs against Ang II-induced changes in cell viability, apoptosis, surface area, β-MHC expression and ROS over-production; 2) The effects were accompanied with the up-regulation of Akt/p-Akt and its downstream eNOS/p-eNOS, and were abolished by PI3K inhibition or partially blocked by NOS inhibition; 3) Depletion of RNAs from EPC-MVs partially or totally eliminated the effects of EPC-MVs. Our data indicate that EPC-MVs protect CMs from hypertrophy and apoptosis through activating the PI3K/Akt/eNOS pathway via the RNAs carried by EPC-MVs. © 2014 Gu et al. Source

Chen X.-F.,Peoples Hospital of Sanya | Liu Z.-X.,Peoples Hospital of Sanya | Chen B.-R.,Peoples Hospital of Sanya | Liu P.,Harbin Medical University | Zheng Y.,Harbin Medical University
International Eye Science

AIM: To investigate the protective effect of resveratrol on human lens epithelial cells against ultraviolet-induced apoptosis. METHODS: Subcultured human lens epithelial cell line, ultraviolet induced cell apoptosis, 20μmol/L resveratrol pretreated cell, the indicators change was observed: rate of apoptosis was detected by flow cytometry and apoptosis-related factors of caspses-3 and caspase-9 were detected by colorimetric detection, ultrastructure changes were observed under transmission electron microscope. RESULTS: Flow cytometry instrument testing found that resveratrol can suppress the apoptosis induced by ultraviolet irradiation, caspses-3 and caspase-9 content in positive control group were significantly higher than that of the negative control group at the same time period, the difference was statistically significant (P<0.05); caspses-3 and caspase-9 content in experimental group were lower than that in the positive control group at the same time, the difference was statistically significant (P<0.05). In addition, the damage of human lens epithelial cells was alleviated with the incubation time of resveratrol elongated. CONCLUSION: Resveratrol may inhibit ultraviolet-induced apoptosis of human lens epithelial cells, it has preventive function against radioactive cataract, and it can provide reliable evidence for pursuing effective medicine to prevent and treat cataract. Copyright 2013 by the IJO Press. Source

Liu Y.-L.,Hainan Medical College | Zhang Y.-B.,Peoples Hospital of Sanya | Li Y.,Peoples Hospital of Sanya | Ma R.-L.,Peoples Hospital of Sanya | And 5 more authors.
Asian Pacific Journal of Tropical Medicine

Objective: To study correlation between the Xba I polymorphism of apoB gene and plasma lipid profiles in Li ethnic group. Methods: Total 151 cases of healthy Li people were recruited randomly by cluster sampling and 200 Han people were recruited as control; blood was drawn to analyze Xba I polymorphism distribution of apoB gene and serum lipid levels. Results: There were lower serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) levels in serum of Li people; while, high density lipoprotein cholesterol (HDL-C), X-/X+ genotype and X+ allele frequencies exhibited higher levels than Han people. Interestingly, HDL-C level was reduced, while LDL-C level was enhanced in subjects carrying heterozygous (X-/X+) genotype compared to homozygous (X-/X-) genotype. Additionally, there were no difference in serum level of triglyceride, TC, apoprotein A (apo A) and apoprotein B (apo B) between Li and Han people, the same results were showed between X-/X+ and X-/X- genotype carriers. Conclusions: Xba I polymorphism of apoB gene is correlated to the profiles of serum lipid level, X-/X+ genotype carriers are phenotyped with higher LDL-C level and lower level of HDL-C in Li ethnic group. © 2014 Hainan Medical College. Source

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