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31.
ObjectivesTo assess the effects of urinary diversion on renal function, we retrospectively investigated renal function over 5 years after urinary diversion using a propensity score matching strategy.MethodsBetween May 1996 and November 2013, 345 consecutive adult patients underwent radical cystectomy and urinary diversion in our hospital; one hundred and fifteen patients with more than a 5-year follow-up were enrolled. Propensity scores were calculated using logistic analysis, and the data used in the analyses included age, gender, Eastern Cooperative Oncology Group Performance Status (ECOG-PS), clinical tumor stage, presence of cardiovascular disease; hypertension; and type 2 diabetes and preoperative eGFR at the initial visit. Multivariate logistic regression analysis was used to assess the risk factors for stage 3B chronic kidney disease (CKD) after the different types of urinary diversion.ResultsContinent and incontinent diversion were performed in 68 and 47 patients, respectively. The mean preoperative eGFR was significantly lower in the incontinent than in the continent group (P < 0.001). In propensity score-matched patients (n = 34 each), no significant differences were observed in pre- and postoperative eGFR and 5-year eGFR decrease rates between the groups. In the incontinent group, the number of postoperative stage 3B CKD patients was significantly increased than the continent group. Using multivariate analysis, independent risk factors significantly associated with stage 3B CKD at 5 years after surgery were older age, eGFR before surgery, incontinent diversion (cutaneous ureterostomy), and postoperative hydronephrosis.ConclusionsThe types of urinary diversion had no significant impact on renal function decline, whereas older age, preexisting impaired renal function, postoperative hydronephrosis, and cutaneous ureterostomy were independent risk factors for stage 3B CKD at 5 years after radical cystectomy.  相似文献   
32.
A microassay for proteases using succinylcasein as a substrate.   总被引:1,自引:0,他引:1  
A photometric assay for proteases has been developed. A chemically modified casein whose amino groups were succinylated was used as a substrate. After incubation with trypsin, chymotrypsin, thermolysin, and subtilisin, the extent of hydrolysis of the substrate was determined with trinitrobenzene sulfonate (TNBS). The whole procedure of the assay was performed in the microtiter plate wells and the increase in the absorbance resulting from the reaction between TNBS and newly formed amino groups in the substrate was able to be determined with a high sensitivity by a microtiter plate reader, enabling the simultaneous measurement of a number of samples. Application of this method to the measurement of proteolytic activity contained in the protein extract of Tapes philippinarum is demonstrated.  相似文献   
33.
TAE226, a bis-anilino pyrimidine compound, has been developed as an inhibitor of focal adhesion kinase (FAK) and insulin-like growth factor-I receptor (IGF-IR). In this study, we investigated the effect of TAE226 on non-small-cell lung cancer (NSCLC), especially focusing on the EGFR mutational status. TAE226 was more effective against cells with mutant EGFR, including the T790M mutant, than against cells with wild-type one. TAE226 preferentially inhibited phospho-EGFR and its downstream signaling mediators in the cells with mutant EGFR than in those with wild-type one. Phosphorylation of FAK and IGF-IR was not inhibited at the concentration at which the proliferation of EGFR-mutant cells was inhibited. Results of the in vitro binding assay indicated significant differences in the affinity for TAE226 between the wild-type and L858R (or delE746_A750) mutant, and the reduced affinity of ATP to the L858R (or delE746_A750) mutant resulted in good responsiveness of the L858R (or delE746_A750) mutant cells to TAE226. Of interest, the L858R/T790M or delE746_A750/T790M mutant enhanced the binding affinity for TAE226 compared with the L858R or delE746_A750 mutant, resulting in the effectiveness of TAE226 against T790M mutant cells despite the T790M mutation restoring the ATP affinity for the mutant EGFR close to that for the wild-type. TAE226 also showed higher affinity of about 15-fold for the L858R/T790M mutant than for the wild-type one by kinetic interaction analysis. The anti-tumor effect against EGFR-mutant tumors including T790M mutation was confirmed in mouse models without any significant toxicity. In summary, we showed that TAE226 inhibited the activation of mutant EGFR and exhibited anti-proliferative activity against NSCLCs carrying EGFR mutations, including T790M mutation.  相似文献   
34.
35.
A new genus, Versicolorisporium, is established for the coelomycetous fungus collected in Japan on dead culms of the bamboos Pleioblastus chino and Sasamorpha borealis. The type species of the genus, V. triseptatum, is characterized by the production of holoblastic, 3-septate, obovoid, versicolored conidia. Versicolorisporium is similar to Toxosporiella, Neohendersonia, Toxosporiopsis, and Scolicosporium in having versicolored conidia, but differs from these genera by the uniloculate pycnidial conidiomata with a periphysate ostiole, lacking paraphyses, and the conidia without black-banded septa. A BLAST search using LSU nrDNA sequence indicates that the new genus is a member of Pleosporales, Dothideomycetes.  相似文献   
36.
The complete amino acid sequences of ribosomal proteins L16, L23 and L33 from the archaebacterium Halobacterium marismortui were determined. The sequences were established by manual sequencing of peptides produced with several proteases as well as by cleavage with dilute HCl. Proteins L16, L23 and L33 consist of 119, 154 and 69 amino acid residues, and their molecular masses are 13538, 16812 and 7620 Da, respectively. The comparison of their sequences with those of ribosomal proteins from other organisms revealed that L23 and L33 are related to eubacterial ribosomal proteins from Escherichia coli and Bacillus stearothermophilus, while protein L16 was found to be homologous to a eukaryotic ribosomal protein from yeast. These results provide information about the special phylogenetic position of archaebacteria.  相似文献   
37.
The TP53 gene (encoding the p53 tumor suppressor) is rarely mutated, although frequently inactivated, in medulloblastoma and ependymoma. Recent work in mouse models showed that the loss of p53 accelerated the development of medulloblastoma. The mechanism underlying p53 inactivation in human brain tumors is not completely understood. We show that ubiquitination factor E4B (UBE4B), an E3 and E4 ubiquitin ligase, physically interacts with p53 and Hdm2 (also known as Mdm2 in mice). UBE4B promotes p53 polyubiquitination and degradation and inhibits p53-dependent transactivation and apoptosis. Notably, silencing UBE4B expression impairs xenotransplanted tumor growth in a p53-dependent manner and overexpression of UBE4B correlates with decreased expression of p53 in these tumors. We also show that UBE4B overexpression is often associated with amplification of its gene in human brain tumors. Our data indicate that amplification and overexpression of UBE4B represent previously undescribed molecular mechanisms of inactivation of p53 in brain tumors.  相似文献   
38.
A major class of disease resistance (R) genes which encode nucleotide binding and leucine rich repeat (NB-LRR) proteins have been used in traditional breeding programs for crop protection. However, it has been difficult to functionally transfer NB-LRR-type R genes in taxonomically distinct families. Here we demonstrate that a pair of Arabidopsis (Brassicaceae) NB-LRR-type R genes, RPS4 and RRS1, properly function in two other Brassicaceae, Brassica rapa and Brassica napus, but also in two Solanaceae, Nicotiana benthamiana and tomato (Solanum lycopersicum). The solanaceous plants transformed with RPS4/RRS1 confer bacterial effector-specific immunity responses. Furthermore, RPS4 and RRS1, which confer resistance to a fungal pathogen Colletotrichum higginsianum in Brassicaceae, also protect against Colletotrichum orbiculare in cucumber (Cucurbitaceae). Importantly, RPS4/RRS1 transgenic plants show no autoimmune phenotypes, indicating that the NB-LRR proteins are tightly regulated. The successful transfer of two R genes at the family level implies that the downstream components of R genes are highly conserved. The functional interfamily transfer of R genes can be a powerful strategy for providing resistance to a broad range of pathogens.  相似文献   
39.
beta-catenin plays an essential role in the Wingless/Wnt signaling cascade and is a component of the cadherin cell adhesion complex. Deregulation of beta-catenin accumulation as a result of mutations in adenomatous polyposis coli (APC) tumor suppressor protein is believed to initiate colorectal neoplasia. beta-catenin levels are regulated by the ubiquitin-dependent proteolysis system and beta-catenin ubiquitination is preceded by phosphorylation of its N-terminal region by the glycogen synthase kinase-3beta (GSK-3beta)/Axin kinase complex. Here we show that FWD1 (the mouse homologue of Slimb/betaTrCP), an F-box/WD40-repeat protein, specifically formed a multi-molecular complex with beta-catenin, Axin, GSK-3beta and APC. Mutations at the signal-induced phosphorylation site of beta-catenin inhibited its association with FWD1. FWD1 facilitated ubiquitination and promoted degradation of beta-catenin, resulting in reduced cytoplasmic beta-catenin levels. In contrast, a dominant-negative mutant form of FWD1 inhibited the ubiquitination process and stabilized beta-catenin. These results suggest that the Skp1/Cullin/F-box protein FWD1 (SCFFWD1)-ubiquitin ligase complex is involved in beta-catenin ubiquitination and that FWD1 serves as an intracellular receptor for phosphorylated beta-catenin. FWD1 also links the phosphorylation machinery to the ubiquitin-proteasome pathway to ensure prompt and efficient proteolysis of beta-catenin in response to external signals. SCFFWD1 may be critical for tumor development and suppression through regulation of beta-catenin protein stability.  相似文献   
40.
Ten erythropoietin (EPO) fractions differing in sialic acid content, ranging from 9.5 to 13.8 mol mol–1 of EPO, were obtained from baby hamster kidney cell-derived recombinant human EPO by Mono Q column chromatography. The mean pI values of the EPO fractions determined by IEF-gel electrophoresis systematically shifted from 4.11 to 3.31, coinciding with the sialic acid content, without a change in the constitution of asialo N-linked oligosaccharides of each fraction. Although a linear relationship between thein vivo bioactivity and the sialic acid content of the fractionated, samples was observed until 12.1 mol mol–1 of EPO, there was no further increase in their activity over 12.4 mol mol–1 of EPO. On the other hand, an inverse relationship between thein vitro bioactivity and sialic acid content of EPO was observed. Also, we showed that thein vivo bioactivity of some fractions with low sialic acid contents was increased after treatment with 2,6-sialyltransferase, but thein vivo bioactivity of the other fractions with high sialic acid contents was either decreased or not affected.Abbreviations EPO erythropoietin - rHuEPO recombinant human erythropoietin - hCG human chorionic gonadotropin - BHK baby hamster kidney - CHO Chinese hamster ovary - NeuAc N-acetyl neuraminic acid - Gal galactose - HRCs hemolyser-resistant cells - WST-1 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium Na - IEF isoelectric focusing - pI isoelectric point  相似文献   
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