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881.
Introduction:  Current protocols for staging gynaecological cancers include cytopathological examination of peritoneal washings taken at the time of definitive surgery. We investigated the clinical usefulness of this procedure.
Methods:  During 2004 and 2005, 140 peritoneal washings were submitted for cytopathological examination in our institutions for staging of 36 ovarian, 101 endometrial and 3 synchronous ovarian/endometrial cancers.
Results:  The washings contained malignant cells in 39 cases (28%). 35 of these cases had high stage disease – not confined to the organ of origin (i.e. stage 2 or more for ovary and stage 3 or more for endometrial). The other 4 were stage 1C ovarian cancers where there was either rupture or tumour involvement of the capsule. In only 2 of the 39 positive cases the cancer was marginally upstaged by the positive washings – these were ovarian cancers upstaged from 2A /B to 2C.
Discussion:  These findings suggest that peritoneal washing cytology as a routine procedure for staging ovarian and endometrial cancer is of limited clinical value. A larger study is needed to determine whether this procedure should continue to be included in staging protocols for gynaecological cancer.  相似文献   
882.
Escherichia coli that sparsely adhere to human epithelial cells are known as diffusely adherent E. coli (DAEC), and the role of the Afa/Dr family of adhesins is now understood. Strains that do not possess Afa/Dr, however, comprise another group of DAEC, of which the pathogenicity remains unknown. The ability to induce interleukin-8 (IL-8) secretion from intestinal epithelial cells might be a feature of enterovirulent bacteria. We previously found that some Afa/Dr DAEC strains induce IL-8 by stimulating epithelial cells with flagella. The present study examines whether non-Afa/Dr DAEC can induce IL-8 in epithelial cells (HEp-2, INT407, and T84). Among 21 strains, 11 (52%; 11/21) induced as much IL-8 as high inducer strains of Afa/Dr DAEC. Adhesion did not significantly differ between high and low inducers; therefore diffuse adhesion alone is probably insufficient to induce IL-8. It was shown that IL-8 induction and the number of intracellular bacteria directly correlated. Wortmannin, an inhibitor of the phosphatidylinositol-3-phosphate kinase, reduced both intracellular bacteria and IL-8 secretion. Motile strains were significantly more prevalent among high (10/11) than low (4/10) inducers. However, 4 low invasive strains hardly induced IL-8 despite their motility. In conclusion, some non-Afa/Dr DAEC invoke the induction of high levels of inflammatory cytokines. Unlike Afa/Dr DAEC, however, non-Afa/Dr strains may require invasion to cause strong induction. These non-Afa/Dr high inducers can be enteropathogenic for the cytokine-inducing properties.  相似文献   
883.
Sex determination from skeletal human remains by discriminant function analysis is one of the methods utilized in the forensic and osteoarcheological sciences. The purpose of the present study is to establish metric standards for sex determination for medieval Anatolian populations using scapular measurements. The database for this research consisted of 93 adult skeletal remains (47 males and 46 females) from the Dilkaya medieval collection. Four measurements were taken: maximum scapular height, maximum scapular breadth, glenoid cavity height, glenoid cavity breadth, and subjected to discriminant function analysis. All measurements demonstrated some degree of sexual dimorphism, with the highest accuracy of sex determination (94.8%) obtained using maximum scapular breadth. Overall accuracies of the functions ranged from 82.9% to 95.0%, with a higher accuracy rate obtained for female skeletons than for males. Population specific discriminant formulas were developed using combinations of measurements, which can be used in ancient Anatolian populations.  相似文献   
884.
In this study we report that deletion of E6-associated protein (E6-AP) in mice results in a smaller prostate gland compared with that in normal wild-type animals. To investigate the mechanism(s) by which E6-AP affects prostate gland growth and development, we carried out both in vitro and in vivo experiments. In this study we show that E6-AP interacts with androgen receptor (AR) in a hormone-dependent manner and enhances the transactivation function of AR. Our in vivo data from E6-AP-null prostate glands show that the level of AR protein is elevated while the level of the AR target protein, probasin, is decreased. In contrast, the level of AR protein is decreased, and its target protein is increased in an E6-AP-overexpressing stable cell line, suggesting that E6-AP modulates both the protein level and the activity of AR. In addition, we show that the levels of phosphatidylinositol 3-kinase, total Akt, and phosphorylated Akt are decreased in E6-AP-null prostate, suggesting that E6-AP deletion down-regulates the signaling of the phosphatidylinositol 3-kinase-Akt pathway. We also show that RhoA negatively regulates AR function, and RhoA levels are increased in E6-AP-null prostate. Furthermore, expression levels of p53, Bax, active caspases, and apoptotic index are increased in E6-AP-null prostate. Collectively, our data suggest that E6-AP deletion attenuates the growth and development of the prostate gland by interfering with AR function as well as by stimulating p53-mediated apoptosis.  相似文献   
885.
A PCR assay has been developed based on a lolB (hemM) gene, which was found to be highly conserved among the Vibrio cholerae species but non-conserved among the other enteric bacteria. The lolB PCR detected all O1, O139 and non-O1/non-O139 serogroup and biotypes of V. cholerae. The analytical specificity of this assay was 100% while the analytical sensitivity was 10 pg/microL and 10(3) CFU/mL at DNA and bacterial level respectively. The diagnostic sensitivity and specificity was 98.5% and 100% respectively.  相似文献   
886.
The investigation aimed to examine the Streptomyces flora of hydrocarbon-contaminated soil and study their capability to grow on diesel fuel as a sole carbon source and their analysis for the presence of the alkane hydroxylase gene (alkB) by PCR. A total of 16 Streptomyces isolates were recovered from hydrocarbon-contaminated soil samples on starch casein nitrate agar medium with the ability of 3 isolates to grow on diesel as evaluated by agar plate diffusion method, enzymatic assay and dry weight measurements. PCR analysis of the isolates for the presence of the alkB gene showed two groups with different band size products; group 1 (G1) (316–334 bp) and group 2 (G2) (460–550 bp). Three isolates (SF.1Ac, SF.2Ba, and SF.3Ad) grew around diesel-containing wells and contained the alkB gene with size band ranged between 320 and 550 bp. However; one isolate (SF.1Aa) did not show any PCR product although it was able to grow on diesel. This implies that the alkB gene is not the only gene that is responsible for the degradation of alkanes. Further, the variation in the G2 fragment size probably indicates different related genes that might be involved in alkane degradation rather than a single gene.  相似文献   
887.
The present study deals with the decolorization of Acid Black 210 by a bioluminescent bacterium, Vibrio harveyi TEMS1, isolated from coastal seawater of Izmir Bay, Turkey. Maximum rate of decolorization of Acid Black 210 was observed when Luria Bertani medium was used. Decolorization of Acid Black 210 was 38.9% and 93.9% at 24 h under shaking and static conditions, respectively. The optimum dye-decolorizing activity of the culture was obtained at 100 ppm initial dye concentration and incubation temperature of 20°C. Vibrio harveyi TEMS1 was also tested for its ability to decolorize four azo dyes (Acid Black 24, Acid Blue 7, Acid Green 20, Acid Yellow 36) in addition to Acid Black 210.  相似文献   
888.
Establishing the mechanisms regulating the autolysis of xylem tracheary elements (TEs) is important for understanding this programmed cell death process. These data demonstrate that two paralogous Arabidopsis thaliana proteases, XYLEM CYSTEINE PROTEASE1 (XCP1) and XCP2, participated in micro-autolysis within the intact central vacuole before mega-autolysis was initiated by tonoplast implosion. The data acquisition was aided by the predictable pattern of seedling root xylogenesis, the availability of single and double total knock-out T-DNA lines, anti-sera that recognized XCP1 and XCP2, and the microwave-assisted processing of whole seedlings prior to immunolabeling and observation in the transmission electron microscope. During secondary wall thickening, XCP1 and XCP2 (in wild type), XCP1 (in xcp2 seedlings) or XCP2 (in xcp1 seedlings) were imported into the TE central vacuole. Both XCP1 and XCP2 heavily labeled dense aggregates of material within the vacuole. However, because of XCP1 deficiency in xcp1 and xcp1 xcp2 TEs, non-degraded cellular remnants first accumulated in the vacuole and then persisted in the TE lumen (longer than in the wild type) after the final mega-autolysis was otherwise complete. This delayed TE clearing phenotype in xcp1 was rescued by complementation with wild-type XCP1. Although TEs in the xcp2 single knock-out cleared comparably with wild type, the non-degraded remnants in xcp1 xcp2 TEs were more densely packed than in xcp1 TEs. Therefore, XCP2 has a minor but distinct role in micro-autolysis. After tonoplast implosion, XCP1 and XCP2 remained associated with disintegrating cellular material as mega-autolysis, aided by additional lytic enzymes, destroyed the bulk of the cellular contents.  相似文献   
889.
The key dinitrile intermediates 4a-d were synthesized by reaction of phenacyl bromide 1 and the appropriate 2-amino-5-bromopyridines to yield 3a-d. Suzuki coupling of 3a-d with 4-cyanophenylboronic acid yielded the 2,6-bis(4-cyanophenyl)-imidazo[1,2-a]pyridine derivatives 4a-d. The bis-amidoximes 5a-d, obtained from 4a-d by the action of hydroxylamine, were converted to the bis-O-acetoxyamidoximes which on catalytic hydrogenation in a mixture of ethanol/ethyl acetate gave the acetate salts of 2,6-bis[4-(amidinophenyl)]-imidazo[1,2-a]pyridines 7a-d. In contrast, catalytic hydrogenation of the bis-O-acetoxyamidoxime of 5a in glacial acetic acid gave the saturated analogue 2,6-bis[4-(amidinophenyl)]-5,6,7,8-tetrahydro-imidazo[1,2-a]pyridine 8. O-Methylation of the amidoximes 5a-d gave the N-methoxyamidines 6a-d. The diamidines showed strong DNA binding affinity, were very active in vitro against T. b. r. exhibiting IC(50) values between 7 and 38nM, but were less effective against P. f. with IC(50) values between 23 and 92nM. Two of the diamidines 7c and 7d were slightly more active than furamidine but less active than azafuramidine in the T. b. r. STIB900 mouse model. Only one prodrug 6b showed moderate activity in the same mouse model.  相似文献   
890.
Prolonged hyperoxic exposure contributes to neonatal lung injury, and airway hyperreactivity is characterized by enhanced contraction and impaired relaxation of airway smooth muscle. Our previous data demonstrate that hyperoxia in rat pups upregulates expression of brain-derived neurotrophic factor (BDNF) mRNA and protein, disrupts NO-cGMP signaling, and impairs cAMP production in airway smooth muscle. We hypothesized that BDNF-tyrosine kinase B (TrkB) signaling plays a functional role in airway hyperreactivity via upregulation of cholinergic mechanisms in hyperoxia-exposed lungs. Five-day-old rat pups were exposed to >or=95% oxygen or room air for 7 days and administered daily tyrosine kinase inhibitor K-252a (50 microg x kg(-1) x day(-1) i.p.) to block BDNF-TrkB signaling or vehicle. Lungs were removed for HPLC measurement of ACh or for in vitro force measurement of lung parenchymal strips. ACh content doubled in hyperoxic compared with room air-exposed lungs. K-252a treatment of hyperoxic pups restored ACh content to room air levels. Hyperoxia increased contraction and impaired relaxation of lung strips in response to incremental electrical field stimulation. K-252a administration to hyperoxic pups reversed this increase in contraction and decrease in relaxation. K-252a or TrkB-Fc was used to block the effect of exogenous BDNF in vitro. Both K-252a and TrkB-Fc blocked the effects of exogenous BDNF. Hyperoxia decreased cAMP and cGMP levels in lung strips, and blockade of BDNF-TrkB signaling restored cAMP but not cGMP to control levels. Therefore, hyperoxia-induced increase in activity of BDNF-TrkB receptor signaling appears to play a critical role in enhancing cholinergically mediated contractile responses of lung parenchyma.  相似文献   
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