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I. Sternberg, R. Rona, S. Olsfanger, S. Lew and I. Leibovitch The clinical significance of class III (suspicious) urine cytology Background: Urine cytology, combined with cystoscopy, is the mainstay of the diagnosis and surveillance of urothelial carcinoma (UC). While classes I and II urine cytology are considered benign and classes IV and V are considered malignant the clinical significance of class III urine cytology is unclear. We evaluated the positive predictive value of class III urine cytology for concurrent and subsequent UC. Methods: The records of all class III urine cytology cases during a 3‐year period were retrospectively reviewed for the presence of concurrent and subsequent UC, determined by cystoscopy and histological confirmation. Results: Of 111 cases, 54 (48.7%) were associated with concurrent UC and 14 (12.6%) with subsequent UC after an initial evaluation negative for malignancy, with a mean time to diagnosis of 10.8 months. Of 27 cases of class III urine cytology with no prior history of UC, 13 (48.1%) had concomitant UC and none had subsequent UC. Of 84 cases of class III urine cytology with a prior history of UC, 41 (48.8%) had a concomitant diagnosis of UC and 14 (16.7%) developed UC during their follow‐up, leading to a total of 55 (65.5%) cases of UC. Conclusions: Patients with class III urine cytology and a prior history of UC should undergo a full initial evaluation of their urinary tract, and should be followed vigorously if this evaluation is negative for malignancy. Patients without a prior diagnosis of UC and class III urine cytology should also undergo a full initial evaluation, while further larger studies are needed to elucidate the need for further follow‐up in such patients. 相似文献
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Simultaneous determination of inosine, hypoxanthine, xanthine, and uric acid and the effect of metal chelators 总被引:3,自引:0,他引:3
We describe a sensitive, reproducible method for the simultaneous determination of the ATP catabolites inosine, hypoxanthine, xanthine, and uric acid in biological samples and organ perfusate using reverse-phase chromatography and multiwavelength detection at 254, 270, and 292 nm. Sample preparation includes precipitating proteins with perchloric acid, neutralizing the sample, passing the supernatant over a polyethyleneimine column, and analyzing the collected fractions by high-performance liquid chromatography. Addition of metal chelators to the perchloric acid resulted in increased values for xanthine, hypoxanthine, and uric acid. The method was sensitive (limit of detection, 0.08 nmol on column; S/N = 4) and linear over the range 0.5-30 microM. Precision and accuracy of the method were evaluated for lung tissue and lung perfusate. Coefficients of variation ranged from 2.8 to 6.1% for perfusate and from 1.7 to 12.6% for tissue. Recoveries for all compounds exceeded 90%. We applied this method to rat lung tissue, lung perfusate, and rat and human blood. Advantages of this method are simultaneous quantitation with excellent sensitivity of all compounds, simplified peak identification by using multiwavelength detection, and improved accuracy by preventing loss of compounds with metal chelators. 相似文献
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Proteoliposomes reconstituted from purified Na+ pumps show neither Ca2+ activation nor bumetanide inhibition of Rb+ uptake, suggesting that the Na+ pump does not mediate these passive fluxes. 相似文献
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Lactic acid is an intermediate-volume specialty chemical for a wide range of food and industrial applications such as pharmaceuticals, cosmetics and chemical syntheses. Although lactic acid production has been well documented, improved production parameters that lead to reduced production costs are always of interest in industrial developments. In this study, we describe the production of lactic acid at high concentration, yield and volumetric productivity utilizing a novel homofermentative, facultative anaerobe Enterococcus faecalis CBRD01. The highest concentration of 182 g lactic acid l−1 was achieved after 38 h of fed-batch fermentation on glucose. The bacterial isolate utilized only 2–13% of carbon for its growth and energy metabolism, while 87–98% of carbon was converted to lactic acid at an overall volumetric productivity of 5 g l−1 h−1. At 13 h of fermentation, the volumetric productivity of lactate production reached 10.3 g l−1 h−1, which is the highest ever reported for microbial production of lactic acid. The lactic acid produced was of high purity as formation of other metabolites was less than 0.1%. The present investigation demonstrates a new opportunity for enhanced production of lactic acid with potential for reduced purification costs. 相似文献
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JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献10.
John P. Ansah Rahul Malhotra Nicola Lew Chi-Tsun Chiu Angelique Chan Steffen Bayer David B. Matchar 《PloS one》2015,10(5)
This study compares projections, up to year 2040, of young-old (aged 60-79) and old-old (aged 80+) with functional disability in Singapore with and without accounting for the changing educational composition of the Singaporean elderly. Two multi-state population models, with and without accounting for educational composition respectively, were developed, parameterized with age-gender-(education)-specific transition probabilities (between active, functional disability and death states) estimated from two waves (2009 and 2011) of a nationally representative survey of community-dwelling Singaporeans aged ≥60 years (N=4,990). Probabilistic sensitivity analysis with the bootstrap method was used to obtain the 95% confidence interval of the transition probabilities. Not accounting for educational composition overestimated the young-old with functional disability by 65 percent and underestimated the old-old by 20 percent in 2040. Accounting for educational composition, the proportion of old-old with functional disability increased from 40.8 percent in 2000 to 64.4 percent by 2040; not accounting for educational composition, the proportion in 2040 was 49.4 percent. Since the health profiles, and hence care needs, of the old-old differ from those of the young-old, health care service utilization and expenditure and the demand for formal and informal caregiving will be affected, impacting health and long-term care policy. 相似文献