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21.
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Background

Cyclo-oxygenase-2 (COX-2), an inducible enzyme expressed in areas of inflammation, is a target of interest for colorectal cancer therapy. Currently, the predictive significance of COX-2 in colorectal cancer remains unclear.

Methods

Tissue microarrays were constructed using 118 colon cancer and 85 rectal cancer specimens; 44 synchronous metastatic colon cancer and 22 rectal cancer lymph nodes were also evaluated. COX-2 expression was assessed by immunohistochemistry. Univariate analysis was used to determine the predictive significance of clinicopathologic variables. Overall survival, disease-specific survival, and disease-free survival were the main outcomes examined.

Results

COX-2 was found to be expressed in 93% of colon cancers and 87% of rectal cancers. Decreased COX-2 expression was related to decreased disease-specific survival (P = .016) and decreased disease-free survival (P = .019) in the rectal cancer cohort but not in the colon cancer cohort.

Conclusions

COX-2 expression has predictive utility for management of rectal but not colon cancer.  相似文献   
23.
BACKGROUND: To evaluate the expression pattern and prognostic significance of the type 1 growth factor receptor (T1GFR) family in colon carcinoma. METHODS: Tissue microarrays were constructed using 127 tumor samples and 47 metastatic lymph nodes and T1GFR family expression was determined by immunohistochemistry. Univariate and multivariate analyses examined clinicopathologic variables for prognostic significance, and the correlation between primary and lymph node expression was determined by Spearman correlation. RESULTS: Overexpression of HER-1, HER-2, HER-3, and HER-4 in tumor samples was 32%, 1%, 12%, and 37%, respectively, and 30%, 0%, 11%, and 24% in nodal samples, respectively. On multivariate analysis, positive margins, lymphatic invasion, and HER-3 expression were significant predictors of survival outcome. There was significant correlation between tumor and regional lymph node expression for the T1GFR family members. Tumor HER-3 expression was associated with lymphatic invasion and distant recurrence. CONCLUSIONS: Tumor HER-3 expression has prognostic utility in individuals with colon carcinoma. Correlation between tumor and lymph node expression of T1GFR family members suggests that tumor receptor status may guide targeted therapy selection.  相似文献   
24.
Accurate knowledge of upper-airway dimensions is required to prevent malpositioning of endotracheal tubes in preterm infants. We measured vocal cord-carina, oral-carina, and nasal-carina distances in situ at autopsy of two groups of infants (less than 1000 and greater than or equal to 1000 g). In all 24 infants, crown-heel length, crown-rump length, and occipitofrontal circumference were better than weight in predicting upper-airway dimensions. Flexion of the neck decreased and extension increased both nasal-carina and oral-carina distances. Lateral rotation produced no significant changes. The postmortem data were not different from nasal-carina distances measured radiologically in 40 living, nasally intubated and ventilated infants, confirming the clinical validity of our findings. Regression equations were derived to predict optimal endotracheal tube lengths based on the external measurements of crown-rump length and crown-heel length.  相似文献   
25.
Summary Using an indirect lymphokin-assay, the leucocyte-migration-inhibition-test (LMI-test), the cellular sensitization of fertile and infertile patients before and after homologous and heterologous intrauterine insemination (IUI) was investigated. In this assay several preparations of spermatozoa (“washed”-, “swim-up”- and “pellet”-spermatozoa) in different concentrations (1, 5 and 10×106 sperms/ml culture medium) and seminal plasma were tested as antigen. In all investigated groups a cellular immune response against spermatic antigen was demonstrable and seemed to be dose dependent. In contrast to fertile women who reacted with an enhancement of the macrophage migration for low concentrations the same concentration of antigen induced an inhibition of macrophage migration in fertile patients. For high concentrations of spermatic antigens there was a difference in the intensity of cell-mediated immune response between fertile and infertile women. Since infertile patients demonstrated an increased level of cell-mediated immune response it is possible that infertility may be caused by this altered immunological reaction. This response changes after multiple IUI-treatment and that change might be caused by the high concentration of spermatic antigens as there was a difference in the intensity of cell-mediated immune response between fertile and infertile women. Since infertile patients demonstrated an increased level of cell-mediated immune response it is possible that infertility may be caused by this altered immunological reaction. This response changes after multiple IUI-treatment and that change might be caused by the high concentration of spermatozoa. The immunological response of infertile patients seems to be similar in those receiving husband and donor IUI.  相似文献   
26.
SecA, an essential component of the general protein secretion pathway of bacteria, is present in Escherichia coli as soluble and membrane-integral forms. Here we show by electron microscopy that SecA assumes two characteristic forms in the presence of phospholipid monolayers: dumbbell-shaped elongated structures and ring-like pore structures. The ring-like pore structures with diameters of 8 nm and holes of 2 nm are found only in the presence of anionic phospholipids. These ring-like pore structures with larger 3- to 6-nm holes (without staining) were also observed by atomic force microscopic examination. They do not form in solution or in the presence of uncharged phosphatidylcholine. These ring-like phospholipid-induced pore-structures may form the core of bacterial protein-conducting channels through bacterial membranes.  相似文献   
27.
Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
28.
Increased cytoplasmic beta-catenin levels and the associated nuclear beta-catenin/T-cell factor (Tcf)-lymphoid enhancer factor (LEF) complex formation have been frequently found in colon cancer. In this context, overproduction of nitric oxide (NO) attributable to inflammatory stimuli in diseases such as ulcerative colitis and Crohn's disease may-contribute to colonic carcinogenesis. Therefore, we examined the modulation by NO of cytoplasmic beta-catenin levels and the formation of the nuclear beta-catenin/LEF-1 DNA binding complex in conditionally immortalized mouse colonic epithelial cells that differed in adenomatous polyposis coli (Apc) genotype, namely young adult mouse colon (YAMC; Apc+/+) and immortal mouse colon epithelium (IMCE; ApcMin/+). Unlike most colon cancer cell lines, this pair of cell lines has either nondetectable or low basal level of beta-catenin when they are cultured under nonpermissive and nonproliferative conditions. Using electrophoretic mobility shift assays, we found that NO-releasing agents (E)-methyl-2-[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexeneamide and S-nitroso-N-acetylpenicillamine greatly enhanced the formation of beta-catenin/LEF-1 DNA binding complex in a concentration- and time-dependent fashion in YAMC and IMCE cells. Significantly, IMCE cells showed a markedly greater amount of nuclear beta-catenin/LEF-1 DNA binding complex in response to NO. Super shift by anti-beta-catenin antibody confirmed the presence of beta-catenin in the complex. Western blot analysis of the soluble cytoplasmic fractions demonstrated that these NO donors caused differential accumulation of cytoplasmic beta-catenin in YAMC and IMCE. In conclusion, this study indicates that the defective beta-catenin degradation machinery attributable to ApcMin/+ mutation in IMCE cells not only affects basal levels but also contributes to NO-induced dysregulation of cytoplasmic beta-catenin and nuclear beta-catenin/LEF-1 DNA binding complex formation.  相似文献   
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30.
A relatively or absolutely too long ulna leads always to pain in the wrist, so that a compensation in length of both forearmbones is achieved by shortening osteotomy. The gradual ulna shortening osteotomy, the stylectomy and the resection of the caput ulnae with or without radius transposition osteotomy are available as shortening operation. In 17 patients of the Gießener Unfallchirurgischen Klinik we performed in 14 cases a shortening osteotomy of the ulna and in 3 cases a resection of the caput ulnae. The shortening osteotomy lead in all cases to a reduction of complaints and to an improvement of the mobility of the wrist. Due to frequent arthropathy the resection of the caput ulnae should be taken more often into consideration in older people.  相似文献   
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