Wood is the product of cambial activity in trees, and the seasonal activity style of cambium directly influences wood biomass production, structures and properties. The seasonal changes in the ultrastructure of the va...Wood is the product of cambial activity in trees, and the seasonal activity style of cambium directly influences wood biomass production, structures and properties. The seasonal changes in the ultrastructure of the vascular cambium activity of Populus tonientosa Carr. planted in Beijing area were examined in shoot tissues collected during 15 months by means of transmission electron microscopy. Before xylem mother cells reactivated completely, the dividing fusiform cells in cambium and new phloem cells had appeared at the same time. The initiation of cambial activity may be related to the bud sprouting and the young leaf growth in shoots. More details about the ultrastructural changes of cambial cells at the onset of cambial activity have been gained. When the large vacuole in active cambial cells divided into smaller ones during the dormant phase, proteinaceous material that disappeared in active cambial cells refilled many of these small vactioles. In addition, lipid droplets and starch granules had the same cycles as proteinaceous material. The plasmalemma invaginations of fusiform cells were observed not only in active phase but also in dormancy. The endomembrane system consisting of nuclear membrane, endoplasmic reticulum (ER), dictyosomes and their secretory vesicles, changed in form and distribution at different phases during a cycle and performed important roles at the onset of active cambium and during the wall formation process of secondary xylem cells. The tangential walls remained relatively thin throughout the year but the radial walls thickened markedly when the cambium was dormant. During the transition from dormancy to activity, a partial autolysis occurred in the radial walls of the cambial cells, especially at the cell wall junctions. A notable feature of the cells at the onset of cambial activity was the thinning of the radial walls.展开更多
Oytoskeletal changes in transformed cells (LM-51) exhibiting obviously metastatie eapabilities were investigated by utilization of double-fluorescent labelling through combinations of:(1) tubulin indirect immunofluore...Oytoskeletal changes in transformed cells (LM-51) exhibiting obviously metastatie eapabilities were investigated by utilization of double-fluorescent labelling through combinations of:(1) tubulin indirect immunofluoresoenoe plus Khodamine-phalloidin staining of F-artins;(2) indirect immunofluorescent staining with α-aotinin polyolonal- and vinoulin monoclonal antibodies. The LM-51 cells which showed metastatic index of >50% were derived from lung metastasis in nude mice after subcutaneous inoculation of human highly metastatic tumor DNA transfected NIH3T3 cell transformants. The parent NIH3T3 cells exhibited well-organized miorotubu-les, prominent stress fibers and adhesion plaques while their transformants showed remarkable oytoskeletal alterations: (1) reduced microtubules but increased MTOC fluorescence; (2) disrupted stress fibers and fewer adhesion plaques with their protein components redistributed in the cytoplasm; (3) F-aotin-and α-actinin/vinculin aggregates appeared in the cytoplasm. These aggregates were dot-like, varied in size (0.1-0.4u,m) and number, located near the ventral surface of the cells. TPA-induced aotin/vinoulin bodies were studied too. Indications that aotin and α-actinin/vinoulin redistribution might be important alterations involved in the expression of metastatio capabilities of LM-51 transformed cells were discussed.展开更多
Background： Exercise-associated menstrual dysfunction （EAMD） is a common health problem in female athletes as a part of female athlete triad （FAT）, a condition related to low energy availability. In this study, w...Background： Exercise-associated menstrual dysfunction （EAMD） is a common health problem in female athletes as a part of female athlete triad （FAT）, a condition related to low energy availability. In this study, we explored the possibility that carbohydrate supplements can improve the status of EAMD and prevent exercise-induced ovarian injury in a FAT rat model. This research aimed to provide experimental evidence with regard to the relationship of energy intervention and EAMD. Methods： Forty-five female Sprague-Dawley rats （2 months old） were randomly divided into five experimental groups： control group （C）, 9-week exercise as model for EAMD （E）, post-EAMD recovery group （R）, oligosaccharide intervention group （O）, and glucose intervention group （G）. All rats were sacrificed at the end of 9 weeks. Serum samples were collected for measuring gonadotropin releasing hormone, follicle stimulating hormone, luteinizing hormone, 1713-estradiol and progesterone levels. The ovaries were taken for investigation of exercise- and carbohydrate-induced follicular subcellular structure changes. Results： Exercise induced irregular menstrual cycles and ovary subcellular structural damages, such as swollenness of mitochondria in rats from groups E and R. Both glucose and oligosaccharide supplements restored well-differentiated mitochondria in the ovarian follicular cells, and a significant improvement of endoplasmic reticulum and Golgi in swollenness in theca cells in groups O and G compared to groups C, E, and R. There was no difference in mitochondria subcellular structural changes between groups O and G. Group E showed attenuation of serum levels of 17β-estradiol and progesterone compared to C. There were no differences of 17β-estradiol serum levels among groups O, G, and R, while group G showed a lower level of progesterone than C. Conclusion： Female adult rats with 9-week continuous exercise can cause menstrual dysregulation as a model for EAMD. Post-EAMD intervention with glucose and oligosaccharide intake can normalize the menstrual cycle, restore the follicular subcellular structure, and reverse the exercise-induced reduction of ovary sex hormones. It suggests a positive feedback of hypothalamus-pituitary-ovary axis might be involved in the molecular mechanisms of energy intake in treating EAMD.展开更多
Objective： The aim of this study was to investigate the clinicopathologic features of gastric adenoma. Methods： Sixty-seven cases of adenoma diagnosis of gastric biopsy specimens using light microscopy, immunohistoc...Objective： The aim of this study was to investigate the clinicopathologic features of gastric adenoma. Methods： Sixty-seven cases of adenoma diagnosis of gastric biopsy specimens using light microscopy, immunohistochemistry, and follow-up methods were studied. Results： Histopathology of gastric adenoma characteristics： nuclear anaplasia, showing increase of nuclear volume and irregular, and the emergence of one or more nucleoli, mitotic ≤ 2/10 high power field （HPF）. Structural changes in the gland： adenoma of the duct much more consistent, sometimes the size of the gland and irregular contour, might be associated with intestinal metaplasia. Increased significantly when the nuclear volume, mitotic 〉 2/10 HPF, irregular gland distortion, branched structures, suggesting the development of adenomas. Immunophenotype： tumor-associated carbohydrate antigens had a higher expression; adenomatous polyposis coli gene （APC） and carcinoembryonic antigen （CEA） expression of closely related with the formation of adenoma. Mucin muc-2 high expression was negatively correlated with muc-1 low expression, the combination of both can help to determine the development and changes in gastric adenoma. Survivin, Bcl-2, p21 and p53 protein expression rare cases, four were combined with the malignant transformation of gastric adenoma was important discriminant. Ki-67 positive cells 20%-40%, and could be used as degree of cell proliferation, a reference indicator of prognosis. Thirty-six to 49 months of follow-up results showed that cured 44.8% （30/67）, there adenomatous hyperplasia 35.8% （24167）, with the development of dysplasia showed 14.4% （11/67）, the development of intramucosal carci- noma were 3.0% （2/67）. Conclusion： Gastric adenomas occur significantly increased nuclear volume, mitotic 〉 2/10 HPF, ir- regular gland distortion, branch-like structure; immunohistochemical staining showed positive expression of muc-2 decreased, muc-1 positive expression; cell proliferation index Ki -67 〉 40%; p21, p53 protein expression occurred, suggesting a tendency to cancer, endoscopic mucosal resection should be as soon as possible.展开更多
Dengue virus(DENV) nonstructural protein 1(NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites(Asn-130 and Asn-207) and 12 conserved cysteine(Cys) residues. Here, we performed site-directed m...Dengue virus(DENV) nonstructural protein 1(NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites(Asn-130 and Asn-207) and 12 conserved cysteine(Cys) residues. Here, we performed site-directed mutagenesis to generate systematic mutants of viral strain TSV01. The results of the subsequent analysis showed that an alanine substitution at the second N-linked glycan Asn-207 in NS1 delayed viral RNA synthesis, reduced virus plaque size, and weakened the cytopathic effect. Three mutants at Cys sites(Cys-4, Cys-55, Cys-291) and a C-terminal deletion(ΔC) mutant significantly impaired RNA synthesis, and consequently abolished viral growth, whereas alanine mutations at Asn-130 and Glu-173 resulted in phenotypes that were similar to the wild-type(WT) virus. Further analysis showed that the Asn-207 mutation slightly delayed viral replication. These results suggest that the three conserved disulfide bonds and the second N-linked glycan in NS1 are required for DENV-2 replication.展开更多
文摘Wood is the product of cambial activity in trees, and the seasonal activity style of cambium directly influences wood biomass production, structures and properties. The seasonal changes in the ultrastructure of the vascular cambium activity of Populus tonientosa Carr. planted in Beijing area were examined in shoot tissues collected during 15 months by means of transmission electron microscopy. Before xylem mother cells reactivated completely, the dividing fusiform cells in cambium and new phloem cells had appeared at the same time. The initiation of cambial activity may be related to the bud sprouting and the young leaf growth in shoots. More details about the ultrastructural changes of cambial cells at the onset of cambial activity have been gained. When the large vacuole in active cambial cells divided into smaller ones during the dormant phase, proteinaceous material that disappeared in active cambial cells refilled many of these small vactioles. In addition, lipid droplets and starch granules had the same cycles as proteinaceous material. The plasmalemma invaginations of fusiform cells were observed not only in active phase but also in dormancy. The endomembrane system consisting of nuclear membrane, endoplasmic reticulum (ER), dictyosomes and their secretory vesicles, changed in form and distribution at different phases during a cycle and performed important roles at the onset of active cambium and during the wall formation process of secondary xylem cells. The tangential walls remained relatively thin throughout the year but the radial walls thickened markedly when the cambium was dormant. During the transition from dormancy to activity, a partial autolysis occurred in the radial walls of the cambial cells, especially at the cell wall junctions. A notable feature of the cells at the onset of cambial activity was the thinning of the radial walls.
文摘Oytoskeletal changes in transformed cells (LM-51) exhibiting obviously metastatie eapabilities were investigated by utilization of double-fluorescent labelling through combinations of:(1) tubulin indirect immunofluoresoenoe plus Khodamine-phalloidin staining of F-artins;(2) indirect immunofluorescent staining with α-aotinin polyolonal- and vinoulin monoclonal antibodies. The LM-51 cells which showed metastatic index of >50% were derived from lung metastasis in nude mice after subcutaneous inoculation of human highly metastatic tumor DNA transfected NIH3T3 cell transformants. The parent NIH3T3 cells exhibited well-organized miorotubu-les, prominent stress fibers and adhesion plaques while their transformants showed remarkable oytoskeletal alterations: (1) reduced microtubules but increased MTOC fluorescence; (2) disrupted stress fibers and fewer adhesion plaques with their protein components redistributed in the cytoplasm; (3) F-aotin-and α-actinin/vinculin aggregates appeared in the cytoplasm. These aggregates were dot-like, varied in size (0.1-0.4u,m) and number, located near the ventral surface of the cells. TPA-induced aotin/vinoulin bodies were studied too. Indications that aotin and α-actinin/vinoulin redistribution might be important alterations involved in the expression of metastatio capabilities of LM-51 transformed cells were discussed.
基金supported by Shanghai Key Laboratory of Human Sport Competence Development and Maintenance,Shanghai University of Sport(NO.11DZ2261100)
文摘Background： Exercise-associated menstrual dysfunction （EAMD） is a common health problem in female athletes as a part of female athlete triad （FAT）, a condition related to low energy availability. In this study, we explored the possibility that carbohydrate supplements can improve the status of EAMD and prevent exercise-induced ovarian injury in a FAT rat model. This research aimed to provide experimental evidence with regard to the relationship of energy intervention and EAMD. Methods： Forty-five female Sprague-Dawley rats （2 months old） were randomly divided into five experimental groups： control group （C）, 9-week exercise as model for EAMD （E）, post-EAMD recovery group （R）, oligosaccharide intervention group （O）, and glucose intervention group （G）. All rats were sacrificed at the end of 9 weeks. Serum samples were collected for measuring gonadotropin releasing hormone, follicle stimulating hormone, luteinizing hormone, 1713-estradiol and progesterone levels. The ovaries were taken for investigation of exercise- and carbohydrate-induced follicular subcellular structure changes. Results： Exercise induced irregular menstrual cycles and ovary subcellular structural damages, such as swollenness of mitochondria in rats from groups E and R. Both glucose and oligosaccharide supplements restored well-differentiated mitochondria in the ovarian follicular cells, and a significant improvement of endoplasmic reticulum and Golgi in swollenness in theca cells in groups O and G compared to groups C, E, and R. There was no difference in mitochondria subcellular structural changes between groups O and G. Group E showed attenuation of serum levels of 17β-estradiol and progesterone compared to C. There were no differences of 17β-estradiol serum levels among groups O, G, and R, while group G showed a lower level of progesterone than C. Conclusion： Female adult rats with 9-week continuous exercise can cause menstrual dysregulation as a model for EAMD. Post-EAMD intervention with glucose and oligosaccharide intake can normalize the menstrual cycle, restore the follicular subcellular structure, and reverse the exercise-induced reduction of ovary sex hormones. It suggests a positive feedback of hypothalamus-pituitary-ovary axis might be involved in the molecular mechanisms of energy intake in treating EAMD.
文摘Objective： The aim of this study was to investigate the clinicopathologic features of gastric adenoma. Methods： Sixty-seven cases of adenoma diagnosis of gastric biopsy specimens using light microscopy, immunohistochemistry, and follow-up methods were studied. Results： Histopathology of gastric adenoma characteristics： nuclear anaplasia, showing increase of nuclear volume and irregular, and the emergence of one or more nucleoli, mitotic ≤ 2/10 high power field （HPF）. Structural changes in the gland： adenoma of the duct much more consistent, sometimes the size of the gland and irregular contour, might be associated with intestinal metaplasia. Increased significantly when the nuclear volume, mitotic 〉 2/10 HPF, irregular gland distortion, branched structures, suggesting the development of adenomas. Immunophenotype： tumor-associated carbohydrate antigens had a higher expression; adenomatous polyposis coli gene （APC） and carcinoembryonic antigen （CEA） expression of closely related with the formation of adenoma. Mucin muc-2 high expression was negatively correlated with muc-1 low expression, the combination of both can help to determine the development and changes in gastric adenoma. Survivin, Bcl-2, p21 and p53 protein expression rare cases, four were combined with the malignant transformation of gastric adenoma was important discriminant. Ki-67 positive cells 20%-40%, and could be used as degree of cell proliferation, a reference indicator of prognosis. Thirty-six to 49 months of follow-up results showed that cured 44.8% （30/67）, there adenomatous hyperplasia 35.8% （24167）, with the development of dysplasia showed 14.4% （11/67）, the development of intramucosal carci- noma were 3.0% （2/67）. Conclusion： Gastric adenomas occur significantly increased nuclear volume, mitotic 〉 2/10 HPF, ir- regular gland distortion, branch-like structure; immunohistochemical staining showed positive expression of muc-2 decreased, muc-1 positive expression; cell proliferation index Ki -67 〉 40%; p21, p53 protein expression occurred, suggesting a tendency to cancer, endoscopic mucosal resection should be as soon as possible.
基金supported by Important National Science & Technology Specific Projects (2012ZX10004219, 2012ZX10004403)the National Natural Scientific Fund of China (81072675)the Wuhan Key Laboratory on Emerging Infectious Diseases and Biosafety
文摘Dengue virus(DENV) nonstructural protein 1(NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites(Asn-130 and Asn-207) and 12 conserved cysteine(Cys) residues. Here, we performed site-directed mutagenesis to generate systematic mutants of viral strain TSV01. The results of the subsequent analysis showed that an alanine substitution at the second N-linked glycan Asn-207 in NS1 delayed viral RNA synthesis, reduced virus plaque size, and weakened the cytopathic effect. Three mutants at Cys sites(Cys-4, Cys-55, Cys-291) and a C-terminal deletion(ΔC) mutant significantly impaired RNA synthesis, and consequently abolished viral growth, whereas alanine mutations at Asn-130 and Glu-173 resulted in phenotypes that were similar to the wild-type(WT) virus. Further analysis showed that the Asn-207 mutation slightly delayed viral replication. These results suggest that the three conserved disulfide bonds and the second N-linked glycan in NS1 are required for DENV-2 replication.
