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21.
Genomic instability and tissue expression of angiogenic growth factors in sporadic colorectal cancer 总被引:3,自引:0,他引:3
BACKGROUND: Chromosomal instability evidenced by a loss of heterozygosity (LOH) is implicated as a predictor of poor survival in patients with colorectal cancer, whereas microsatellite instability (MSI) is associated with improved survival rates. We investigated the relationship between tumor expression of angiogenic growth factors and genomic alterations in colorectal cancer. METHODS: Two genotypes, LOH and MSI, determined by microsatellite markers in the 4 cancer-related chromosomes 2p, 3p, 17p, and 18q, were analyzed in 73 patients with colorectal cancer. The tumor-specific expression of vascular endothelial growth factor and hepatocyte growth factor (HGF) were quantified, and the interleukin-6 network also was evaluated. RESULTS: MSI-positive neoplasms showed a lesser expression of both tumor growth factors and interleukin-6. In contrast, LOH-positive neoplasms showed a greater expression of HGF and a lesser expression of interleukin-1-receptor antagonist. MSI neoplasms were correlated with favorable prognosis in agreement with previous findings. CONCLUSIONS: The suppressed production of angiogenic growth factors in MSI cancers partly might explain the better prognosis in MSI-positive patients. The interleukin-6 network, which upregulates production of vascular endothelial growth factor and HGF, might be involved in this mechanism. 相似文献
22.
C-Reactive Protein as a Prognostic Variable That Reflects Uncontrolled Up-Regulation of the IL-1-IL-6 Network System in Colorectal Carcinoma 总被引:4,自引:0,他引:4
Miki C Konishi N Ojima E Hatada T Inoue Y Kusunoki M 《Digestive diseases and sciences》2004,49(6):970-976
Up-regulation of the IL-1-IL-6 network stimulates systemic expression of C-reactive protein (CRP). This cytokine network system plays a pivotal role in inducing angiogenic growth factors in intestinal mucosa. Serum CRP level and tissue concentrations of cytokines in colorectal cancer patients were determined and an in vitro model was employed to determine the time course of induction of IL-6 in Caco-2 cells. Increased serum CRP was associated with recurrent disease and shorter survival time. Intense surgical stress and the presence of an acute phase reactant were independently associated with overexpression of IL-6 in the tumor. Enhanced IL-6 protein expression in Caco-2 cells induced by the initial treatment with IL-1beta or lipopolysaccharide could be abrogated by additional presupplementation of IL-1ra. The presence of an acute phase reactant reflects uncontrolled up-regulation of the local IL-1-IL-6 network system in the tumor, which may enhance the survival and proliferation of remnant cancer cells after tumor resection. 相似文献
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Development of a diagnostic PCR assay targeting the Mn-dependent superoxide dismutase gene (sodA) for identification of Streptococcus gallolyticus 下载免费PDF全文
A PCR-based assay to identify Streptococcus gallolyticus has been developed. The assay uses an oligonucleotide primer pair targeting a partial sequence of the manganese-dependent superoxide dismutase gene (sodA). The assay distinguished members of the S. gallolyticus group from other, closely related taxa successfully by yielding a 408-bp specific amplicon. 相似文献
25.
Histological evaluation of medial patellofemoral ligament reconstructed using the Leeds-Keio ligament prosthesis 总被引:1,自引:0,他引:1
In a total of 15 knees from 15 patients undergoing medial patellofemoral ligament reconstruction using an artificial substitute and a medial retinaculum slip coverage for recurrent patellar dislocation, the reconstructed ligaments were histologically evaluated using hematoxilin-eosin and elastic van Gieson stains. The artificial substitute was a mesh-type Leeds-Keio ligament. The mean age of the patients at the time of surgery was 20 years (range; 13-38 years). The mean interval from initial reconstruction to gathering was 53 months (range; 11-109 months). In the tissue over the artificial ligament, longitudinally aligned collagen fiber bundles with spindle-shaped nuclei were formed in all specimens except one specimen of 11 months postsurgery, but it seemed to be mature ligament only in specimens more than 60 months postsurgery. The tissue inside the artificial ligament was immature as a whole in all specimens, although 13 out of the 15 specimens had regularly aligned collagen fiber bundles slightly or in some portions. 相似文献
26.
Hwansung Lee Yoshiaki Ikeuchi Eiki Akagawa Eisuke Tatsumi Yoshiyuki Taenaka Takao Yamamoto 《Journal of artificial organs》2009,12(2):98-104
Our group is currently developing a pneumatic ventricular assist device (PVAD). In this study, in order to select the optimal
bileaflet valve for our PVAD, three kinds of bileaflet valve were installed and the flow was visualized downstream of the
outlet valve using the particle image velocimetry (PIV) method. To carry out flow visualization inside the blood pump and
near the valve, we designed a model pump that had the same configuration as our PVAD. The three bileaflet valves tested were
a 21-mm ATS valve, a 21-mm St. Jude valve, and a 21-mm Sorin Bicarbon valve. The mechanical heart valves were mounted at the
aortic position of the model pump and the flow was visualized by using the PIV method. The maximum flow velocity was measured
at three distances (0, 10, and 30 mm) from the valve plane. The maximum flow velocity of the Sorin Bicarbon valve was less
than that of the other two valves; however, it decreased slightly with increasing distance it the X-Y plane in all three valves.
Although different bileaflet valves are very similar in design, the geometry of the leaflet is an important factor when selecting
a mechanical heart valve for use in an artificial heart. 相似文献
27.
Kadota K Satoh E Ochiai M Inoue N Tsuji N Igarashi I Nagasawa H Mikami T Claveria FG Fujisaki K 《Parasitology research》2002,88(8):781-784
Phenol oxidase (PO, EC 1.10.3.1) activity was detected in the hemolymph of the fourth instar nymphs of the argasid tick, Ornithodoros moubata, with peak levels corresponding to the days before the majority of the nymphs had molted, suggestive of a protective role of PO during the ecdysial phase. Higher PO activity was detected in plasma relative to the hemolymph and was negligible in hemocytes. The concentration of the hemolymph and plasma assayed clearly influenced the level of PO activity, and was significantly reduced ( P<0.005) after treatment with 1-phenyl-2 thiourea, a specific PO inhibitor. This is the first report of the existence of PO in the hemolymph and plasma of a soft tick species. The regulation of PO activity and its precise role in soft tick immunity, particularly during the ecdysial phase, are interesting and need to be examined further. 相似文献
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Morita H Hasegawa T Minamoto T Oda Y Inui K Tayama H Nakao N Nakamoto Y Ideura T Yoshimura A 《Virchows Archiv : an international journal of pathology》2003,442(2):163-168
Collagenofibrotic glomerulopathy is considered as a form of glomerulopathy in which organized collagen type III progressively deposits. We report a case of this disease with widespread expression of collagen type V. A 65-year-old woman was admitted to our hospital for further evaluation of nephrotic-range proteinuria. The patient had had anemia and hypertension for 9 years, and proteinuria for 3 years. A renal biopsy specimen showed a remarkable mesangial expansion with Congo red-negative and periodic acid-Schiff-positive deposits. At the ultrastructural level, two forms of bundling fibers were found in the mesangium and subendothelial side of the glomerular basement membranes (GBM). The GBM itself appeared normal. Immunohistochemical investigation showed that the glomerular lesions were strongly reactive with both anti-collagen type-III and -V antibodies. Immunoelectron microscopy demonstrated collagen type V in both forms of bundling fibers. Despite therapy, her renal function declined. The clinical course and renal pathology of this case were in accordance with collagenofibrotic glomerulopathy except for the widespread expression of collagen type V. Collagen type V is a fibrillar collagen capable of forming banding fibrils. This report poses the question whether collagen type V accumulates only in this particular case or whether it is a normal component in collagenofibrotic glomerulopathy. 相似文献