678 research outputs found
Updates in intravesical electromotive drug administration(A (R)) of mitomycin-C for non-muscle invasive bladder cancer
Electromotive drug administration(A (R)) (EMDA) increases the local drug efficacy by controlling and enhancing transmembranous transport into tissue. EMDA of intravesical mitomycin-C (MMC) has been used for treatment of non-muscle invasive bladder cancer (NMIBC) for about a decade on the basis of laboratory studies that demonstrated an enhanced administration rate of MMC into all bladder wall layers after EMDA compared to standard instillation/passive diffusion (PD). Higher MMC concentrations might have a clinical impact since EMDA was associated with lower recurrence rates than PD in randomized studies. Further data suggest that EMDA/MMC is at least equivalent to BCG in treatment of high-risk bladder tumours. In addition, BCG combined with EMDA/MMC as well as preoperative EMDA/MMC are new therapeutic strategies with promising preliminary results in terms of higher remission rates and longer remission times. In summary, these findings suggest that EMDA for MMC delivery in the bladder could be a major therapeutic breakthrough in the treatment of NMIBC
Intravesical electromotive drug administration of mitomycin-C for non-muscle invasive bladder cancer
This article reviews intravesical application of electromotive drug administration (EMDA) for the treatment of bladder cancer and the evidence in support of intravesical passive diffusion chemotherapy in the management of non-muscle invasive bladder cancer. Two recently published randomised trials adopting protocols that use EMDA to enhance urothelial transport of intravesical mitomycin-C showed it provided a therapeutical advantage and suggested that intravesical passive diffusion administration of chemothera-peutic drugs may be suboptimal. Further studies are required to demonstrate feasibility and advantage of intravesical EMDA of mitomycin-C in the wider uro-oncological community
Localised prostate cancer and hemophilia A (AHA): Case report and management of the disease.
Acquired Hemophilia A (AHA) is a rare bleeding diathesis characterized by the development of autoantibodies against factor VIII (FVIII). About half of the cases are idiopathic and the other half are associated with autoimmune diseases, postpartum problems, infections, inflammatory bowel disease, drugs, lymphoproliferative disorders or solid tumors . AHA is associated with malignancies in 7-15% of cases. We report a case of AHA in a 65 year old patient with prostatic carcinoma, who underwent retropubic radical prostatectomy (RP)
Evolution of the mass-loss rate during atmospheric and pressurized slow pyrolysis of wheat straw in a bench-scale reactor
In the present study, the effects of the absolute pressure (0.1 or 0.5 MPa) and the reactor atmosphere (pure N2 or a mixture of CO2/N2) on the pyrolysis behavior of wheat straw pellets (at 500 °C) were investigated. The most interesting aspect of this work was the use of a weighing platform (with a maximum capacity of 100 kg and a resolution of 0.5 g) to monitor the real-time mass-loss data for the biomass sample (with an initial mass of 400 g). It was observed that an increased pressure considerably affects the mass-loss profiles during the pyrolysis process, leading to higher devolatilization rates in a shorter period of time. Regardless of the pyrolysis atmosphere, an increase in the absolute pressure led to higher yields of gas at the expense of produced water and condensable organic compounds. This finding could be due to the fact that an increased pressure favors the exothermic secondary reactions of the intermediate volatile organic compounds in both liquid and vapor phases. The switch from pure N2 to a mixture of CO2 and N2 at 0.1 MPa also led to a remarkable increase in the yield of produced gas at the expense of the total liquid. This could be mainly due to the promotion of the thermal cracking of the volatile organic compounds at a high partial pressure of CO2, which is also consistent with the measured higher yields of CH4 and CO. The increased yield of CO can also be seen as a direct result of the enhanced reverse Boudouard reaction, which can also explain the much higher specific surface area (and ultra-micropore volume) measured for the biochar produced under the same operating conditions (0.1 MPa and a mixture CO2/N2 as pyrolysis medium)
Evolution of the Mass Loss Rate During Atmospheric and Pressurized Slow Pyrolysis of Wheat Straw in a Bench-Scale Reactor
A deep study focused on the significant effect of the absolute pressure on the yield of produced gas during the slow pyrolysis of biomass was carried out. In addition, the evolution of the mass loss rate linked to the pyrolysis process was also analyzed
Retropubic, laparoscopic, and robot-assisted radical prostatectomy: surgical, oncological, and functional outcomes: a systematic review.
<b><i>Objectives:</i></b> Despite the wide diffusion of minimally invasive approaches, such as laparoscopic (LRP) and robot-assisted radical prostatectomy (RALP), few studies compare the results of these techniques with the retropubic radical prostatectomy (RRP) approach. The aim of this study is to compare the surgical, functional, and oncological outcomes and cost-effectiveness of RRP, LRP, and RALP. <b><i>Methods:</i></b> A systematic review of the literature was performed in the PubMed and Embase databases in December 2013. A ‘free-text' protocol using the term ‘radical prostatectomy' was applied. A total of 16,085 records were found. The authors reviewed the records to identify comparative studies to include in the review. <b><i>Results:</i></b> 44 comparative studies were identified. With regard to the perioperative outcome, LRP and RALP were more time-consuming than RRP, but blood loss, transfusion rates, catheterisation time, hospitalisation duration, and complication rates were the most optimal in the laparoscopic approaches. With regard to the functional and oncological results, RALP was found to have the best outcomes. <b><i>Conclusion:</i></b> Our study confirmed the well-known perioperative advantage of minimally invasive techniques; however, available data were not sufficient to prove the superiority of any surgical approach in terms of functional and oncologic outcomes. On the contrary, cost comparison clearly supports RRP.</jats:p
Hexaminolevulinate hydrochloride in the detection of nonmuscle invasive cancer of the bladder
Clinical trials have shown that hexaminolevulinate (HAL) fluorescence cystoscopy improves the detection of bladder tumors compared with standard white-light cystoscopy, resulting in more efficacious treatment. However, some recent meta-analyses report controversially on recurrence-free rates with this procedure. A systematic review of literature was performed from December 2014 to January 2015 using the PubMed, Embase and Cochrane databases for controlled trials on photodynamic diagnosis (PDD) with HAL. A total of 154 publications were found up to January 2015. Three of the authors separately reviewed the records to evaluate eligibility and methodological quality of clinical trials. A total of 16 publications were considered eligible for analysis. HAL-PDD-guided cystoscopy increased overall tumor detection rate (proportion difference 19%, 95% confidence interval [CI] 0.152-0.236) although the benefit was particularly significant in patients with carcinoma in situ (CIS) lesion (proportion difference 15.7%, 95% CI 0.069-0.245) and was reduced in papillary lesions (Ta proportion difference 5.9%, 95% CI 0.014-0.103 and T1 proportion difference 1.2%, 95% CI 0.033-0.057). Moreover, there were 15% of patients (95% CI 0.098-0.211) with at least one additional tumor seen with PDD. With regard to recurrence rates, the data sample was insufficient for a statistical analysis, although the evaluation of raw data showed a trend in favor of HAL-PDD. This meta-analysis confirms the increased tumor detection rate by HAL-PDD with a most pronounced benefit for CIS lesion
Biomass-derived carbons physically activated in one or two steps for CH4/CO2 separation
The present study aims at evaluating the suitability of producing activated carbons (ACs) derived from wheat straw by a one-step synthesis approach, as an alternative to more conventional two steps production processes (i.e., pyrolysis and subsequent activation). The performance of the produced ACs, in one or two steps, as sustainable and selective CO2 adsorbents for CH4/CO2 separation is compared. In addition, the influence of pyrolysis conditions on the properties of the resulting two-step ACs is carefully analyzed. We show that the biochar-based precursors of ACs presenting the best textural properties were obtained under mild conditions of maximum temperature and absolute pressure during pyrolysis. The one-step ACs were fully comparable —in terms of textural properties as well as CO2 uptake and selectivity— to those produced by the more conventional two-step synthesis process. In addition, results obtained from breakthrough curve simulations highlight that the best AC in terms of CH4 recovery under dynamic conditions was produced by a one-step activation. Therefore, the one-step process appears to be as an attractive route for the production of engineered carbon materials, which can lead to significant cost savings in large-scale production systems
Why stem/progenitor cells lose their regenerative potential
Nowadays, it is clear that adult stem cells, also called as tissue stem cells, play a central role to repair and maintain the tissue in which they reside by their selfrenewal ability and capacity of differentiating into distinct and specialized cells. As stem cells age, their renewal ability declines and their capacity to maintain organ homeostasis and regeneration is impaired. From a molecular perspective, these changes in stem cells properties can be due to several types of cell intrinsic injury and DNA aberrant alteration (i.e epigenomic profile) as well as changes in the tissue microenviroment, both into the niche and by systemic circulating factors. Strikingly, it has been suggested that aging-induced deterioration of stem cell functions may play a key role in the pathophysiology of the various agingassociated disorders. Therefore, understanding how resident stem cell age and affects near and distant tissues is fundamental. Here, we examine the current knowledge about aging mechanisms in several kinds of adult stem cells under physiological and pathological conditions and the principal aging-related changes in number, function and phenotype that determine the loss of tissue renewal properties. Furthermore, we examine the possible cell rejuvenation strategies. Stem cell rejuvenation may reverse the aging phenotype and the discovery of effective methods for inducing and differentiating pluripotent stem cells for cell replacement therapies could open up new possibilities for treating age-related diseases
Biomass-derived activated carbon as catalyst in the leaching of metals from a copper sulfide concentrate
Chalcopyrite is the resource with the highest amount of Cu content representing around 70–80% of the known reserves in the world. However, chalcopyrite like other copper sulfides, is usually found in deposits with grades around 0.4–0.5% copper. The exploitation of these reserves using traditional flotation methods followed by pyrometallurgical treatment of copper concentrate is at the limit of economic viability. Hydrometallurgical route would be more suitable for treating of these low-graded sulfide ores. However, chalcopyrite is refractory in ferric/sulfuric acid media and shows slow dissolution rates. For this a number of researches were carried out to accelerate the kinetics of leaching by adding pyrite, iron powder, nanosized silica, coal and activated carbon. The main objective of the present work was to study the use of one biomass-derived activated carbon as catalysts in the leaching of copper from chalcopyrite. Sulfuric acid solution of pH 1 with 5 g L-1 of Fe3+ was used as leaching agent. Experiments were performed at 90 °C and 250 rpm, during 48 and 96 h. Concentration of Cu, Zn, As, Sb and Co in the liquid phase was determined in order to evaluate their extraction degree, whereas solid residues were characterized by SEM-EDS and XRD. The presence of biomass-derived activated carbon significantly increased the extraction of copper, decreasing the leaching of arsenic. Furthermore, the use of biomass-derived activated carbon led to lower amounts of crystalline sulfur in the final residue
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