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[en] Large-scale morphology-controlled SWCNT/polymeric microsphere arrays can be obtained by a wet chemical self-assembly technique. The loading of SWCNTs, the length of SWCNTs, and the size and nature of polymeric microspheres can easily be controlled. Similar results can also be reached using this method for MWCNTs. In both types of CNTs, they form an interesting interactive 'net' structure on spheres and sphere joints. The SWCNT/PS-modified Au electrode was used for detection of uric acid by cyclic voltammetry and single-potential time-based techniques. The preliminary results show that the modified electrode presents good sensitivity and stability to uric acid
[en] The electrochemical biosensing efficiency of uric acid (UA) detection on an electrochemically reduced graphene oxide (ERGO)-decorated electrode surface was studied by using various amine linkers used to immobilize ERGO. The amine linkers aminoethylphenyldiazonium , 2,2'-(ethylenedioxy)bis(ethylamine), 3-aminopro-pyltriethoxysilane, and polyethyleneimine were coated on indium-tin-oxide electrode surfaces through chemical or electrochemical deposition methods. ERGO-decorated surfaces were prepared by the electrochemical reduction of graphene oxide (GO), which was immobilized on the amine-coated electrode surfaces through the electrostatic interaction between GO and the ammonium ion of the linker on the surface. We monitored the sensing results of electrochemical UA detection with differential pulse voltammetry. The ERGO-modified surface presented electrocatalytic oxidation of UA and ascorbic acid. Among the different amines tested, 3-aminopropyltriethoxysilane provided the best biosensing performance in terms of sensitivity and reproducibility.
[en] Objective: A meta-analysis was conducted to determine the accuracy of dual-energy computed tomography (DECT) for differentiating urinary uric acid and calcified calculi. Methods: The databases PubMed, EMBASE, Web of Science, and the Cochrane Library were searched up to May 2016 for relevant original studies. Data were extracted to calculate the pooled sensitivity, specificity, diagnostic odds ratio (OR), positive and negative likelihood ratios (PLR and NLR), and areas under summary receiver operating characteristic (AUROC) curves for analysis. Results: Nine studies (609 stones in 415 patients) were included. For differentiating uric acid (UA) and non-UA calculi with DECT, the analysis indicated: pooled weighted sensitivity, 0.955 (95% CI, 0.888–0.987); specificity, 0.985 (95% CI, 0.970–0.993); PLR, 0.084 (95% CI, 0.041–0.170); NLR 33.327 (95% CI, 18.516–59.985); and diagnostic OR 538.18 (95% CI, 195.50–1478.5). The AUROC value was 0.9901. For calcified stones, the analysis indicated: pooled weighted sensitivity, 0.994 (95% CI, 0.969–1); specificity, 0.973 (95% CI, 0.906–0.997); PLR, 11.200 (95% CI, 4.922–25.486); NLR 0.027 (95% CI, 0.010–0.072); and diagnostic OR 654.89 (95% CI, 151.31–2834.4). The AUROC value was 0.9915. Conclusion: This meta-analysis found that DECT is a highly accurate noninvasive method for characterizing urinary uric acid and calcified calculi.
[en] An in vitro study sought to determine the feasibility of using computed tomography (CT) to analyze the chemical composition of renal calculi and thus aid in selecting the best treatment method. Sixty-three coded calculi were scanned in a water bath. Region-of-interest measurements provided the mean, standard deviation, and minimum and maximum pixel values for each stone. These parameters were correlated with aspects of the stones' chemical composition. A multivariate analysis showed that the mean and standard deviation of the stones' pixel values were the best CT parameters for differentiating types of renal calculi. By using computerized mapping techniques, uric acid calculi could be perfectly differentiated from struvite and calcium oxalate calculi. The latter two types also were differentiable, but to a lesser extent. CT has a potential role as an adjunct to clinical and laboratory methods for determining the chemical composition of renal calculi in an effort to select optimal treatment
[en] The extent of caffeine sensitization following ultraviolet light irradiation for various UV-sensitive strains and the parental resistant strain are compared. Several features of these results are to be noted. (i) With the exception of the M28 strain, the more sensitive the strain is to UV, the lesser the effect of post-irradiation treatment with caffeine. For example, the D10 with caffeine for the wt parental strain is 0.13 of that with no caffeine, whereas for the three most sensitive strains, γs-13 (radB), HPS73 (rad AradB), and HPS82 (rad AradC), this ratio is about 1.0. The slight desensitizing effect of caffeine with γs-13 is reproducible and was observed previously. (orig./AJ)
[en] National Health and Nutrition Examination Survey 2007–2014 data (N = 6844) for adults aged ≥ 20 years were analyzed to estimate associations of perfluoroalkyl substances (PFAS), namely, PFOA, PFOS, PFDA, PFHxS, and PFNA with uric acid across stages of declining glomerular function. The population was stratified by the estimated glomerular filtration rates (eGFR) stages accompanying kidney disease: GF-1 with eGFR > 90 mL/min/1.73 m2; GF-2 with eGFR 60–89 mL/min/1.73 m2; GF-3A with eGFR 45–59 mL/min/1.73 m2; and GF-3B/4 with eGFR 15–44 mL/min/1.73 m2. Adjusted and unadjusted geometric means of uric acid increased from GF-1 to GF-3B/4 for males and females. Adjusted geometric means for uric acid were higher for males by 1.38, 1.03, and 0.62 mg/dL for GF-1, GF2, and GF-3 respectively but for GF-3B/4, females had higher adjusted geometric means than males by 0.16 mg/dL, revealing narrowing of sex differences in uric acid as glomerular function declines. The direction of association between PFAS and uric acid was positive for GF-1 and GF-2 for males and for every PFAS except PFDA for females. For males for GF-3B/4, association between every PFAS except PFHxS and uric acid was found to be negative (p < 0.01). For females, only PFHxS actually reverses its relationship with increasing stages of renal disease. Uric acid associations with PFAS reverse in males with advanced renal failure. An implication is that previously reported association of PFAS exposure with uric acid is not due to renal failure. Understanding of other biomarkers associated with both PFAS exposure and renal failure may benefit from similar evaluation.
[en] A recent trend in diagnosis of oral cancer in young age is observed, however its impact on various clinicopathological parameters needs to be explored. The aim of the current study was to compare and analyze impact of age at diagnosis with clinicopathological parameters of oral squamous cell carcinoma patients. Methods: In this cross sectional study conducted at Department of Oncology Ziauddin Hospital Karachi, we included histologically confirmed cases of oral squamous cell carcinoma. The patients were categorized as young age group (40yrs and younger) and old age group (41 yrs and above). A total of 115 patients diagnosed between 2013 and 2016 were enrolled in the study. The variables considered were age at diagnosis, sex, site of lesion, positive family history, tumor grade, stage, uric acid level and survival. Results: A statistically significant difference was observed between two age groups in overall survival, uric acid level and positive family history of cancer. No significant difference was observed in tumor location, grade and stage. Conclusion: Majority of oral cancer patients present at an advanced stage irrespective of age at diagnosis but young age has an overall improved survival. Moreover, a positive family history of cancer in young age group mandates further exploration of possible role of genetic polymorphisms which might be responsible for early onset of the disease.