63 research outputs found

    Quenching of chlorophyll fluorescence induced by silver nanoparticles

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    The interaction between chlorophyll (Chl) and silver nanoparticles (AgNPs) was evaluated by analyzing the optical behavior of Chl molecules surrounded by different concentrations of AgNPs (10, 60, and 100 nm of diameter). UV–Vis absorption, steady state and time-resolved fluorescence measurements were performed for Chl in the presence and absence of these nanoparticles. AgNPs strongly suppressed the Chl fluorescence intensity at 678 nm. The Stern-Volmer constant (KSV) showed that fluorescence suppression is driven by the dynamic quenching process. In particular, KSV was nanoparticle size-dependent with an exponential decrease as a function of the nanoparticle diameter. Finally, changes in the Chl fluorescence lifetime in the presence of nanoparticles demonstrated that the fluorescence quenching may be induced by the excited electron transfer from the Chl molecules to the metal nanoparticles

    Epidemiology of bladder cancer: A systematic review and contemporary update of risk factors in 2018

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    CONTEXT: Bladder cancer (BC) is a significant health problem, and understanding the risk factors for this disease could improve prevention and early detection. OBJECTIVE: To provide a systematic review and summary of novel developments in epidemiology and risk factors for BC. EVIDENCE ACQUISITION: A systematic review of original articles was performed by two pairs of reviewers (M.G.C., I.J., F.E., and K.P.) using PubMed/Medline in December 2017, updated in April 2018. To address our primary objective of reporting contemporary studies, we restricted our search to include studies from the last 5yr. We subdivided our review according to specific risk factors (PICO [Population Intervention Comparator Outcome]). EVIDENCE SYNTHESIS: Our search found 2191 articles, of which 279 full-text manuscripts were included. We separated our manuscripts by the specific risk factor they addressed (PICO). According to GLOBOCAN estimates, there were 430000 new BC cases and 165000 deaths worldwide in 2012. Tobacco smoking and occupational exposure to carcinogens remain the factors with the highest attributable risk. The literature was limited by heterogeneity of data. CONCLUSIONS: Evidence is emerging regarding gene-environment interactions, particularly for tobacco and occupational exposures. In some populations, incidence rates are declining, which may reflect a decrease in smoking. Standardisation of reporting may help improve epidemiologic evaluation of risk. PATIENT SUMMARY: Bladder cancer is common worldwide, and the main risk factors are tobacco smoking and exposure to certain chemicals in the working and general environments. There is ongoing research to identify and reduce risk factors, as well as to understand the impact of genetics on bladder cancer risk

    Human Fibroblast Sheet Promotes Human Pancreatic Islet Survival and Function In Vitro

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    In previous work, we engineered functional cell sheets using bone marrow-derived mesenchymal stem cells (BM-MSCs) to promote islet graft survival. In the present study, we hypothesized that a cell sheet using dermal fibroblasts could be an alternative to MSCs, and then we aimed to evaluate the effects of this cell sheet on the functional viability of human islets. Fibroblast sheets were fabricated using temperature-responsive culture dishes. Human islets were seeded onto fibroblast sheets. The efficacy of the fibroblast sheets was evaluated by dividing islets into three groups: the islets-alone group, the coculture with fibroblasts group, and the islet culture on fibroblast sheet group. The ultrastructure of the islets cultured on each fibroblast sheet was examined by electron microscopy. The fibroblast sheet expression of fibronectin (as a component of the extracellular matrix) was quantified by Western blotting. After 3 days of culture, islet viabilities were 70.2 ± 9.8%, 87.4 ± 5.8%, and 88.6 ± 4.5%, and survival rates were 60.3 ± 6.8%, 65.3 ± 3.0%, and 75.8 ± 5.6%, respectively. Insulin secretions in response to high-glucose stimulation were 5.1 ± 1.6, 9.4 ± 3.8, and 23.5 ± 12.4 μIU/islet, and interleukin-6 (IL-6) secretions were 3.0 ± 0.7, 5.1 ± 1.2, and 7.3 ± 1.0 ng/day, respectively. Islets were found to incorporate into the fibroblast sheets while maintaining a three-dimensional structure and well-preserved extracellular matrix. The fibroblast sheets exhibited a higher expression of fibronectin compared to fibroblasts alone. In conclusion, human dermal fibroblast sheets fabricated by tissue-engineering techniques could provide an optimal substrate for human islets, as a source of cytokines and extracellular matrix

    The Impact of Blue Light Cystoscopy with Hexaminolevulinate (HAL) on Progression of Bladder Cancer - A New Analysis

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    Background: The International Bladder Cancer Group (IBCG) recently proposed a new definition of disease progression in non-muscle invasive bladder cancer (NMIBC), including change in T-stage, change to T2 or higher or change from low to high grade. Objective: To establish whether blue light cystoscopy with hexaminolevulinate (HAL) impacts the rate of progression and time to progression using the revised definition. Methods: An earlier long-term follow-up of a controlled Phase III study reported outcomes following blue light cystoscopy with HAL (255 patients) or white light (WL) cystoscopy (261 patients) in NMIBC patients. The data was re-analysed according to the new definition. Results: In the original analysis, after 4.5 years (median), eight HAL and 16 WL patients were deemed to have progressed (transition from NMIBC to muscle invasive bladder cancer, (T2-4)). According to the new definition, additional patients in both groups were found to have progressed: 31 (12.2%) HAL vs 46 (17.6%) WL (p = 0.085) with four (1.6%) HAL and 11 (4.2%) WL patients progressing from Ta to CIS. Time to progression was longer in the HAL group (p = 0.05). Conclusions: Applying the new IBCG definition there was a trend towards a lower rate of progression in HAL patients, particularly in those progressing from Ta to CIS. Time to progression was significantly prolonged. This suggests that patients should receive blue light cystoscopy with HAL rather than WL at resection. Adoption of the new definition could allow more patients at risk of progression to be treated appropriately earlier

    What Is the Prognostic and Clinical Importance of Urothelial and Nonurothelial Histological Variants of Bladder Cancer in Predicting Oncological Outcomes in Patients with Muscle-invasive and Metastatic Bladder Cancer? A European Association of Urology Muscle Invasive and Metastatic Bladder Cancer Guidelines Panel Systematic Review

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    Contains fulltext : 215744.pdf (publisher's version ) (Closed access)CONTEXT: Variant histology of muscle-invasive (MIBC) and metastatic (mBC) bladder cancer may define the cancer treatment modality and oncological outcomes. OBJECTIVE: To determine the prognostic effect and impact of therapy of urothelial and nonurothelial histological variants on the oncological outcomes of MIBC and mBC. EVIDENCE ACQUISITION: Medline, Embase, Cochrane controlled trial databases, and ClinicalTrials.gov were systematically searched. Patients with histological variants of MIBC or/and mBC from prospective and retrospective comparative studies and single-arm case series published after the year of 2000 were included. Treatment outcomes (overall, recurrence-free, and disease-specific survival) were extracted and reported. Risk of bias (RoB) assessment was performed using Quality in Prognosis Studies tool. EVIDENCE SYNTHESIS: The search yielded 2450 unique articles, of which 41 articles involving a total of 27 672 patients with histological variants were included. Twenty-eight studies had a comparative study design. Two different study settings were seen: large database studies without centralised pathological review and small series with re-review by uropathologists. Although most of the histological variants show similar oncological outcomes after radical cystectomy (RC), signet ring cell, spindle cell, and neuroendocrine tumours showed inferior survival compared with pure urothelial bladder cancer (PUC). Owing to potential misleading interpretations and reporting as well as large heterogeneity between studies, a narrative synthesis approach instead of subgroup analyses was used. Most studies had a moderate RoB. CONCLUSIONS: The data about prognosis and treatment of the variant histology are still immature and assessed mostly in cystectomy patients. Based on this systematic review, all patients with MIBC should be treated with RC. Neoadjuvant chemotherapy may be beneficial for patients with micropapillary, plasmacytoid, sarcomatoid, and mixed variants, and especially for patients with neuroendocrine tumours. Metastatic bladder cancer should be treated as PUC. PATIENT SUMMARY: In this report, we looked at the prognosis and treatment of different bladder cancer histologies. We found that outcomes varied with divergent histologies and appropriate treatment should be based on the histological finding

    Repeat Transurethral Resection in Non-muscle-invasive Bladder Cancer: A Systematic Review

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    CONTEXT: Initial treatment for most bladder cancers (BCs) involves transurethral resection (TUR) or tumours. Often more cancer is found after the initial treatment in around half of patients, requiring a second resection. Repeat transurethral resection (reTUR) is recommended for high-risk, non-muscle-invasive bladder cancer (NMIBC) to remove any residual disease and improve cancer outcomes. OBJECTIVE: To systematically review the practice and therapeutic benefit of an early reTUR for high-risk NMIBC. EVIDENCE ACQUISITION: A systematic review of original articles was performed using PubMed/Medline and Web of Science databases in December 2016 (initial) and October 2017 (final). We searched the references of included papers. EVIDENCE SYNTHESIS: We screened 15 209 manuscripts and selected 31 detailing 8409 persons with high-grade Ta and T1BC for inclusion. Detrusor muscle was found at initial TUR histology in 30-100% of cases. Residual tumour at reTUR was found in 17-67% of patients following Ta and in 20-71% following T1 cancer. Most residual tumours (36-86%) were found at the original resection site. Upstaging occurred in 0-8% (Ta to ≥T1) and 0-32% (T1 to ≥T2) of cases. Conflicting data report the impact of reTUR on subsequent recurrence and cancer-specific mortality. Recurrence for Ta was 16% in the reTUR group versus 58% in the non-reTUR group. For T1, recurrence ranged from 18% to 56%, but no clear trend was identified between reTUR and control. No clear relationship between reTUR and progression was found for Ta, although for T1 rates were higher in the non-reTUR group in series with control populations (5/6 studies). Overall mortality was slightly reduced in the reTUR group in two studies with controls (22-30% vs 26-36% [no reTUR]). CONCLUSIONS: Residual tumour is common after TUR for high-risk NMIBC. The reTUR helps in the diagnosis of this residual cancer and may improve outcomes for cancers initially staged as T1. PATIENT SUMMARY: Some bladder cancers (BCs) are aggressive but confined to the bladder surface. Initial treatment includes endoscopic resection. More cancer is found after the initial treatment in approximately half of patients. In the aggressive but confined group of BC, a second resection, a few weeks after the first, may help find this residual cancer and improve outcomes, although the evidence quality for this is weak
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