Rhodium effects on Pt anode materials in a direct alkaline ethanol fuel cell

The development of efficient catalysts for ethanol oxidation in alkaline medium requires a synthetic approach that may prevent the surfactant molecules from being adsorbed at the catalytic sites and decreasing the electrochemical performance of the final direct ethanol fuel cell. Toward this goal, the recently reported surfactant-less Bromide Anion Exchange (BAE) method, appears as a promising route to conveniently aim at preparing PtRh alloys dispersed on carbon substrates. The catalysts prepared herein by the BAE method were characterized physicochemically to obtain structural information on the PtRh/C nanomaterials, their morphology (size and shape), and their chemical and surface composition. Electrochemical behavior and properties of these electrodes were then investigated in a half-cell before the implementation of a direct ethanol fuel cell (DEFC) in a home-made anion exchange membrane Teflon cell. The analysis of the electrolytic solution in the anodic compartment by chromatography revealed that acetate was the major reaction product and the carbonate amount increased with the Rh content in the bimetallic composition. With 2.8–3.6 nm particle sizes, the Pt₅₀Rh₅₀/C catalyst exhibited the highest activity towards the ethanol electrooxidation.

The development of efficient catalysts for ethanol oxidation in alkaline medium requires an approach that avoids surfactant molecules from being adsorbed at active sites and decreasing the electrochemical performance of the direct ethanol fuel cell.     

Mitigation of Cd toxicity by Mn in young plants of cacao,evaluated by the proteomic profiles of leaves and roots

Cd is a non-essential metal and highly toxic to plants, animals and humans, even at very low concentrations. Cd has been found in cocoa beans and in their products, as in the case of chocolate. Mn plays an important role in photosynthetic and can interact with Cd and attenuate its toxic effects on plants. The objective of this work was to evaluate the mechanisms of Mn response in the mitigation of Cd toxicity in young plants of the CCN 51 cacao genotype submitted to 0.8?mmol?Cd kg^?1, 1.6?mmol Mn kg^?1 or the combination of 0.4?mmol?Cd kg^?1?+?0.8?mmol Mn kg^?1 soil, together with the control treatment (without addition of Cd and Mn in soil), by means of analysis of changes in the profile of exclusive proteins (EP) and differentially accumulated proteins (DAP). Leaf and root proteins were extracted and quantified from the different treatments, followed by proteomic analysis. About eight DAP and 38 EP were identified in leaves, whereas in roots 43 DAP and 21 EP were identified. Some important proteins induced in the presence of Cd and repressed in the presence of Cd?+?Mn or vice versa, were ATPases, isoflavone reductase, proteasome and chaperonin. It was concluded that proteins involved in oxidoreduction and defense and stress response processes, in addition to other processes, were induced in the presence of Cd and repressed in the presence of Cd?+?Mn. This demonstrated that Mn was able to mitigate the toxic effects of Cd on young plants of the CCN 51 cocoa genotype.

     

Impact of Cardiovascular Interventions on the Quality of Life in the Elderly

INTRODUCTION

The elderly population is growing rapidly. Political and socio-economic changes led to the demographic transition in this population with the highest number of surgeries and as well as many comorbidities.

OBJECTIVE

To evaluate the impact of cardiovascular intervention on quality of life of elderly patients after three and six months.

METHODS

Analytical prospective cohort study with elderly between 60 and 80 years of age, of both sexes, with a diagnosis of coronary artery disease and underwent cardiovascular intervention during the period June 2010 to June 2011. Data were collected by individual interviews in the pre and postoperative periods (after three and six months) by telephone. We used the SF-36 to analyse quality of life in order to assess the physical and mental health of the study population.

RESULTS

Of the 44 individuals evaluated, 59.1% were men, 75% in the range of 65 to 74 years, 38.6% were white and 38.6% were black, 31.8% were uneducated, 43.2% were married and 68.2% had less than a minimum wage. Prevailed patients: non-diabetics (68.2%), non-obese (81.8%), hypertensive (84.1%), non-alcoholic and non-smokers (68.2% and 61.4%, respectively). A significant increase in the average of the SF-36 scores between pre and post-surgical periods (three and six months) for the domains: functional capacity, pain, general health, vitality and emotional aspect.

CONCLUSION

The elderly population undergoing intervention may have cardiovascular benefits and improvements of quality of life. Physical fitness improvement measures can be taken to resume that capability.     

Effect of n-3 and n-6 fatty acids on proliferation and differentiation of promyelocytic leukemic HL-60 cells

Promyelocytic leukemic HL-60 cells were incubated with different fatty acids. Arachidonic acid (AA; 20:4, n-6) and eicosapentaenoic acid (EPA; 20:5, n-3) were the most potent inhibitors of proliferation in a dose- dependent way. Retinoic acid (RA) was used as a positive control. Inhibitors of cyclooxygenase and lipoxygenase or addition of antioxidants did not influence the effect of EPA or AA on cell proliferation. Increased capacity to generate superoxide anions after phorbol ester treatment and a reduced serglycin messenger RNA level in cells treated with AA or EPA indicated that these fatty acids induced differentiation in HL-60 cells similar to that induced by RA. However, down-regulation of the c-myc mRNA level, also typical for differentiation with RA in HL-60 cells, was not observed in cells incubated with AA or EPA. Flow cytometric analyses showed that in cultures incubated with AA or EPA, the proportion of cells in the G1 phase of the cell cycle increased. Similar effects were observed with RA. By flow cytometry and light scatter analyses it could be shown that AA made 8% of the cells apoptotic and 7% necrotic. The corresponding numbers were 21% and 10% for RA-treated cells, and 19% and 32% for EPA- treated cells. The present study shows that AA and EPA reduce the proliferation rate of HL-60 cells. This is mediated by mechanisms independent of eicosanoids or lipid peroxidation products and is due to effects both on apoptosis/necrosis and cell differentiation.     

Autologous bone marrow transplantation for acute myeloid leukemia using busulfan plus etoposide as a preparative regimen

We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML.     

Insulin-like growth factor (IgF)-I,IgF binding protein-3, and prostate cancer: correlation with gleason score

Introduction

Non-androgenic growth factors are involved in the growth regulation of prostate cancer (PCa).

Objective

This is the first Brazilian study to correlate, in a population of patients operated for PCa, PSA, total testosterone, insulin-like growth factor-I (IGF-I) and insulin-like growth factor-binding protein-3 (IGFBP-3) with Gleason score and to compare with a control group with benign prostate hyperplasia (BPH).

Materials and Methods

This retrospective single-center study included 49 men with previously diagnosed PCa and 45 with previously diagnosed BPH. PSA, testosterone, IGF-I, IGFBP-3 were determined in both groups.

Results

PSA and IGFBP-3 levels were significantly higher in the PCa group as compared to the BPH group (p<0.001 and p=0.004, respectively). There was a significant difference when we compared the PSA before surgery (p<0.001) and at the inclusion in the study (p<0.001) and IGFBP3 (0.016) among patients with Gleason <7, ≥7 and BPH. In the PCa group, PSA, testosterone, IGF-I and IGFBP-3 levels were comparable between Gleason <7 and ≥7.

Conclusions

Our data suggest that in localized PCa, the quantification of PSA and, not of IGF-1, may provide independent significant information in the aggressiveness. IGFBP-3 could be a biochemical marker of disease control in PCa patients.     

Proximal Esophageal Contractions in Laryngectomized Patients

After laryngectomy for treatment of laryngeal cancer, the distal esophageal contractions have low amplitude. Our hypothesis is that proximal esophageal contractions are also impaired. We studied the proximal esophageal contractions in 20 laryngectomized patients (16 men) with a mean age of 44.2 years, 12 rehabilitated patients with esophageal speech, and 12 controls (7 men, mean age of 46.5 years). We used the manometric method with continuous perfusion. All subjects were studied in the sitting position and performed five swallows of a 5-ml bolus of water alternated with five dry swallows. The contractions were measured 2 cm below the high-pressure zone of the pharyngoesophageal transition. The results showed that the amplitude and duration of contractions were different in laryngectomized patients compared with controls. The amplitude of contractions of patients (wet swallows: 37.3 ± 20.7 mmHg, mean ± SD) was lower than that of controls (81.1 ± 31.7 mmHg). The duration of contractions was also lower in laryngectomized patients (2.2 ± 0.7 s) than in controls (2.6 ± 0.6 s). We conclude that the proximal esophageal contraction amplitude and duration of laryngectomized patients are lower than controls, a fact suggesting that laryngectomy may affect the proximal esophageal contractions.