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1.
In Vivo Molecular Imaging Characterizes Pulmonary Gene Expression During Experimental Lung Transplantation 总被引:2,自引:0,他引:2
Sekhar Dharmarajan Makio Hayama James Kozlowski Takaaki Ishiyama Mikio Okazaki Phillip Factor G. Alexander Patterson Daniel P. Schuster 《American journal of transplantation》2005,5(6):1216-1225
Experimental gene therapy is a promising strategy to prevent ischemia-reperfusion (I/R) injury and allograft rejection after lung transplantation, and methods will eventually be needed to characterize pulmonary transgene expression in vivo in humans. Therefore, we studied positron emission tomography (PET) as a means of performing in vivo molecular imaging in rodent models of lung transplantation. Rats were transfected endotracheally with adenovirus encoding a fusion gene of a mutant Herpes simplex virus-1 thymidine kinase and the green fluorescent protein gene (the former serving as an imaging reporter gene). Twenty-four hours after transfection, lungs were transplanted in groups representing normal transplantation, I/R injury and acute allograft rejection. Imaging was obtained either 24 h after transplantation to study reperfusion injury or 4 days after transplantation to study graft rejection. After imaging, lungs were excised and analyzed for thymidine kinase activity. Imaging detected transgene expression in transplanted lungs even in the presence of acute rejection or I/R injury. The PET imaging signal correlated with in vitro lung tissue assays of thymidine kinase activity (r(2) = 0.534). Thus, noninvasive molecular imaging with PET is a feasible, sensitive and quantitative method for characterizing pulmonary transgene expression in experimental lung transplantation. 相似文献
2.
Yusuf K. Durlu Sei-ichi Ishiguro Akiko Yoshida Takezo Mito Makio Tsuchiya Makoto Tamai 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1990,228(1):44-48
We used morphological, biochemical and immunohistochemical methods to assess the response of Müller cells after experimental
lensectomy-vitrectomy in rabbits. We observed widened intercellular spaces between the Müller cells and nerve fibers of ganglion
cells, and increased electron opacity in the Müller cells of eyes injected with silicone oil. No apparent morphological changes
were detected in the Müller cells of air-injected eyes. The specific and total activities of Müller cell-marker enzymes (glucose
6-phosphatase and glutamine synthetase) showed an initial increase, followed by a decrease. Glial fibrillary acidic protein
immunoreactivity was not found in the Müller cells of the normal rabbit retina but was exhibited after surgery. Our results
showed that markers of Müller cells associated with glycogenolysis and/or gluconeogenesis, glutamate-glutamine cycle and cytoskeletal
protein metabolism were affected by the experimental lensectomy-vitrectomy. 相似文献
3.
4.
Takao Kato Tsunehito Kimura Ryuhei Miyakawa Shinichi Tanaka Akiho Fujii Kazuko Yamamoto Shingo Kameoka Kyoichi Hamano Makio Kawakami Motohiko Aiba 《World journal of surgery》1997,21(1):49-56
p
= 0.0007) and tumor necrosis (TN) (HMC:
p
= 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all
patients (
p
= 0.0086 and
p
= 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted
a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including
all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were
not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant
independent prognostic factor associated with long-term survival in Japanese breast cancer patients. 相似文献
5.
Yasushi Tohi Takashi Nakano Haruyuki Makio Shigekazu Matsui Terunori Fujita Tsutomu Yamaguchi 《Macromolecular chemistry and physics.》2004,205(9):1179-1186
Summary: Bis(phenoxy‐imine) Zr complexes with MAO activation can produce polyethylenes with well‐defined bimodal molecular weight distributions. Polymerization behavior indicates that minor changes in the ligand structures can have a significant effect on the modality of the resulting polyethylenes. Although there is no direct relationship between the bimodal catalytic behavior and the structure of a precatalyst complex in solution, a precatalyst complex having a methyl or methoxy group para to the phenoxy‐oxygen inclined to exhibit bimodal behavior whereas that with a pentafluorophenyl group on the imine‐nitrogen displayed unimodal behavior. Polymerization results suggest that bimodal behavior is linked to the presence of two kinds of cationic active species, which arise from different modes of ligand coordination. A qualitative correlation was found between the calculated amounts of possible cationic active species and the uni‐ and bimodal catalytic behavior. Based on the results obtained, we concluded that the bimodal polyethylenes are produced by two kinds of cationic active species having two available cis‐located sites with cis‐N, trans‐O and cis‐N, cis‐O arrangements. The results introduced herein are rare examples of the production of well‐defined bimodal polyethylenes using a single precatalyst.
6.
骨骼肌介电行为的理论模型仿真 总被引:1,自引:1,他引:1
在 10 0 Hz~ 10 0 MHz范围内 ,应用椭圆壳介电理论模型 ,经过模拟仿真蛙骨骼肌细胞的介电行为 ,确定了蛙骨骼肌细胞的椭圆壳模型各相参数。为将来对骨骼肌疲劳、肌营养不良和肌肉萎缩等病症的模型分析奠定理论基础。 相似文献
7.
M Imai T Shibata K Moriguchi M Yamamoto H Hayama 《Okajimas folia anatomica Japonica》1991,68(2-3):155-160
Some researchers have already described the fowl proventriculus. However, we believed there was a need for detailed carbohydrate histochemical investigations on the same glands. Moreover, some researchers had erred about the lamina muscularis mucosae. The results of these investigations are as follows. 1. The proventricular glands consist of both superficial and profound gastric glands. 2. The superficial glands are distributed in the lamina propria mucosae while the profound glands exist in the tela submucosa. 3. The superficial glands are simple, branched tubular glands. The columnar glandular cells are arranged in a simple layer and react strongly to PAS, AB (pH 2.5 and 0.5). These appear to be dark purple when they are stained with PAS-AB (pH 2.5). Some other methods have also been tried. 4. Judging from the data 3), the superficial gastric glands contain neutral, weak and strong acids, sulfuric and acid mucopolysaccharides, sialomucin, and II and III neutral mucus type. 5. Glandular cells in the body and basal portions of the superficial gastric glands contain a large number of fine pepsinogen granules. 6. Judging from the data of 3)-5), we believe that the superficial gastric glands are undifferentiated gastric glands and that they are same kinds of glands that are found in mammals. 7. A large number of profound gastric glands fill the tela submucosa. They are compound tubular glands, and are composed of many glandular alveoli. Their columnar glandular cells are arranged in a simple layer. 8. These glandular cells react moderately to PAS, negatively to AB (pH 2.5 and 0.5) and PAS-AB (pH 2.5). Moreover, we observed some other reactions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Kaneko T Ota H Hayama M Akamatsu T Katsuyama T 《Virchows Archiv : an international journal of pathology》2000,437(5):514-520
Helicobacter pylori infection induces the expression of a secretory component (SC) in gastric epithelial cells. We investigated the cell lineage of the SC- and immunoglobulin (Ig) A-expressing epithelial cells in H. pylori-infected gastric mucosa. Materials were obtained by means of gastric biopsy from H. pylori-infected patients (24 cases) before and after the eradication of H. pylori, from five normal uninfected volunteers, and from three gastrectomy cases. Acetic acid-ethanol-fixed and paraffin-embedded specimens were examined using histochemical staining for gastric mucins (periodic acid oxidation-thionine Schiff reaction-concanavalin A-horse radish peroxidase staining) by means of immunostaining for gastric mucins (45M1 and HIK1083), intestinal cells (MUC2 and CD10), Ki67, H. pylori, SC, and IgA. The SC and IgA were not found in normal gastric mucosa. The expressions of the SC and IgA in gastric surface mucous cells and mucous neck cells in the generating zone of the gastric mucosa of H. pylori-infected patients were significantly higher before eradication of H. pylori than after the eradication. These mucous cells have the potential for SC-mediated translocation of IgA into the gastric lumen, and this may act as part of the antibacterial defense system against H. pylori infection in the gastric generating zone. 相似文献
9.
In the gastric mucosa of Japanese patients, ciliated cells were found in association with intestinal metaplasia. The cells occurred frequently in the pyloric mucosa of nearly half of the cases examined but rarely in the cardiac mucosa of total 12 cases, but never adjacent to the chief cells of gastric glands. The ciliated cells were always found in the basal part of cardiac and pyloric glands, but never in the surface or in the foveolar epithelium. Furthermore, ciliated cells containing a few small mucus granules and simultaneously possessing numerous cilia and basal bodies were noted. Ciliated cells in the gastric mucosa have been found mainly in elderly Japanese patients, but were also observed exceptionally in one Chinese, two Swedes and one American. These ciliated cells are not present in the normal human gastric and intestinal mucosa, and therefore a new term, "ciliated metaplasia", is proposed for their occurrence. Acta Pathol Jpn 40: 98–106, 1990. 相似文献
10.
Kazuya Takeda Shuhei Sakakibara Kazuo Yamashita Daisuke Motooka Shota Nakamura Marwa Ali El Hussien Jun Katayama Yohei Maeda Masanobu Nakata Shigeyuki Hamada Daron M. Standley Masaki Hayama Takashi Shikina Hidenori Inohara Hitoshi Kikutani 《The Journal of allergy and clinical immunology》2019,143(3):1163-1175.e15