•A flaxseed oil diet was added with a propolis product and vitamin E for dairy cows.•The propolis-based product is rich in phenolic compounds, mainly Artepillin C.•Flaxseed oil diet reduced rumen ...protozoa and bacteria involved in lipolysis.•The propolis-based product enhanced Butyrivibrio fibrisolvens count in the rumen.•Association of antioxidants did not alter intake, digestibility, and fermentation.
The effects of supplying diets with flaxseed oil and a propolis-based product, with or without vitamin E, on dry matter intake, ruminal and total digestibility, ruminal parameters, biohydrogenation, and bacterial and protozoal populations in dairy cows were evaluated. Four Holstein cows, with a mean weight of 584 ± 52 kg and 90 ± 39 days in milk, were randomly assigned to a 4 × 4 Latin square. Diets were composed of 600 g/kg of dry matter (DM) as roughage and 400 g/kg of concentrate for the following diets: control diet; diet with 25 g flaxseed oil/kg DM (FO); diet with flaxseed oil, 1.2 g propolis-based product/kg DM (PBP); diet with flaxseed oil, PBP, and 375 IU vitamin E/kg DM. The flaxseed oil diet tended to reduce populations of Entodinium and total protozoa (P = 0.09) and significantly increased Butyrivibrio fibrisolvens (P = 0.008) count. However, Anaerovibrio lipolytica (P < 0.001) and Methanobrevibacter ruminantium counts (P = 0.013) were significantly reduced with the flaxseed oil diet. The PBP diet, with or without vitamin E, tended to enhance Butyrivibrio fibrisolvens (P = 0.09) count. The flaxseed oil diet tended to decrease the intake of organic matter (P = 0.09) and total carbohydrates (P = 0.05). Ruminal and total digestibility of crude protein and ether extract were higher with flaxseed oil. The PBP did not influence omasal nutrient flow, digestibility, short-chain fatty acid concentrations, pH, and ammonia in the rumen. Flaxseed oil addition in diets significantly increased (P < 0.05) the production of fatty acid (FA) cis3-18:3 and CLA cis9,trans11-18:2 in milk, and tended (P < 0.10) to increase FA 18:0 and cis9-18:1. PBP in diet significantly increased (P < 0.05) the production of CLA cis9,trans11-18:2 in milk. Among the ingredients added to the diets, flaxseed oil had the greatest effect on the parameters evaluated, and both PBP and PBP-E diets did not interfere with flaxseed oil activity in the rumen.
Felbamate has proven to be an effective therapy for treating refractory epilepsy. However, felbamate therapy has been limited due to the associated reports of hepatotoxicity and aplastic anemia. ...Previous research from our laboratory has proposed 2-phenylpropenal as the reactive metabolite in felbamate bioactivation and identified its mercapturates in the urine of rats and patients undergoing felbamate therapy. While the reaction between 2-phenylpropenal and GSH has been shown to occur spontaneously under physiological conditions, the potential catalysis by glutathione transferases (GST) has remained unknown. The work presented here demonstrates a role for GST in the detoxification of 2-phenylpropenal. The kinetic data show that 2-phenylpropenal is a substrate for all three isoforms tested, with a k cat/K m of 0.275 ± 0.035 μM-1 s-1 for GSTM1-1, 0.164 ± 0.005 μM-1 s-1 for GSTP1-1, and 0.042 ± 0.005 μM-1 s-1 for GSTA1-1. Given that electrophilic substrates such as 2-propenal have been shown to inhibit GSTs, we also examined the inhibition of GSTM1-1, GSTP1-1 and GSTA1-1 by 2-phenylpropenal. The enzyme inhibition studies demonstrate that 2-phenylpropenal inhibits GSTP1-1 and GSTM1-1. The inhibition of GSTP1-1 was completely reversible upon filtration and reconstitution in buffer containing 10 mM GSH. However, 2-phenylpropenal inhibition of GSTM1-1 was irreversible under the same conditions. The irreversible inhibition of GSTM1-1 may be important in understanding the toxicities associated with felbamate. Given that 2-phenylpropenal is both a substrate and irreversible inhibitor for GSTM1-1, GSTM1-1 represents a potential target for 2-phenylpropenal haptenization in vivo, which may in turn mediate the observed idiosyncratic reactions.
We report a study of the structural and magnetic properties, as well as of the heat release, of an iron/wustite composite, prepared from iron powder and water by high energy mechanical milling. We ...identify that the produced sample consists of alpha -Fe nanoparticles embedded in a wustite matrix and has high stability in time. Moreover, we observe that it presents noticeable features, as exchange bias effect at low temperatures and, when an alternating magnetic field is applied, its temperature reaches ~46 degreesC in ~600 s. Thus, the results and the possibility of tuning the magnetic properties of alpha -Fe nanoparticles embedded in a wustite matrix, through interface interactions, place this system as a very attractive candidate for biomedical applications such as magnetic hyperthermia agent for cancer therapy.
Autologous bone marrow transplantation in the acute leukemias and lymphomas offers potentially curative treatment in patients who do not have a histocompatible, allogeneic donor. Results of marrow ...autografting in the lymphomas are especially encouraging, with disease-free survivals of 50-60% in patients who have failed primary and secondary treatment regimens. In the acute leukemias, one may expect 20-40% relapse-free survival after autologous marrow transplantation. We feel that ex vivo treatment ("purging") is necessary to eradicate occult tumor cells from autologous remission marrow in hematological malignancies, but this remains a controversial issue to some investigators. Preliminary studies of autologous bone marrow transplantation are promising in multiple myeloma and certain childhood tumors, and autografting is currently being explored in the treatment of other solid tumors such as adenocarcinoma of the breast.
In an attempt to reduce the incidence and severity of acute graft-versus-host disease (GVHD), we have decreased the number of bone marrow (BM) lymphocytes in the donor marrow graft before bone marrow ...transplantation (BMT) using counterflow centrifugal elutriation (CCE). In a phase I-11 clinical trial, 23 patients received lymphocyte-depleted BM allografts from their HLA-identical, mixed lymphocyte culture (MLC)-nonreactive sibling donors. The patients entered in the study were deemed to be at high risk for treatment failure on the basis of age (greater than 30 years; median, 39 years) and the result of our skin explant assay predictive of acute GVHD. Patients predicted not to develop acute GVHD by this assay were excluded from this study. All patients received a standard lymphocyte dose of 0.5 × 106 morphologic lymphocytes per kilogram ideal body weight (IBW) in the marrow graft and were maintained on cyclosporine A (CsA) immunosuppression for 170 days after BMT. Prompt hematopoietic recovery occurred in 22 of 23 patients with a median time to an absolute neutrophil count (ANC)≥500/μL of 21 days. Donor cell engraftment was subsequently verified by cytogenetic and/or DNA analysis in all of 21 evaluable patients. No patient developed systemic acute GVHD. Only five (22%) developed cutaneous GVHD (clinical stage 1) that required steroid treatment, including one patient who failed to engraft. The median follow-up of the patients enrolled in this study is 14 months (range, 5 to 20 months). Actuarial survival 1 year after BMT is 83%. Thus, in two consecutive clinical trials using CCE to deplete donor BM of alloreactive lymphocytes (1.0 × 105 versus 0.5 × 106 lymphocytes/kg), we have demonstrated that the procedure does not interfere with BM engraftment and is effective in decreasing the incidence and severity of acute GVHD. Furthermore, comparison of these studies has revealed a differential dose response relationship between the number of graft lymphocytes, protection of engraftment, and induction of acute GVHD. Although there appears to be a modest relationship between lymphocyte dose and time to hematopoietic recovery, the 50% reduction in lymphocyte dose from that used in our previous trial resulted in a marked decrease in acute GVHD without compromising engraftment.
Among many bioglass (BG) compositions, gel-BG 58S has been indicated in the literature for applications as bone graft due to its promising use to repair bone defects. However, its physical and ...biological properties also depend of choice of precursors. The use of phosphoric acid as a source of P2O5 changes the thermal behavior of BG and in the presence of HNO3 increases the rate of hydrolysis and reduces the size of sol particles, thus influencing the surface area and in turn rate of apatite formation of bioactive glasses. In addition, the addition of concentrated NH4OH decreases the gelation time and new bioactive materials have been produced using Ca/Sr substitution in BG compositions. Thus, the aim of this work was to prepare BG 58S by the sol-gel technique at room temperature using phosphoric acid (PA) as the phosphorus precursor compared with conventional precursor triethylphosphate (TEP) and to evaluate the effect of the adding NH4OH (1 or 2 M) as gelation catalyst in order to select the better route to Sr incorporate. The products were characterized using XRD, FTIR and confocal Raman spectroscopy. The composition prepared with 1M NH4OH (PA-1M) presented more evidence of NBO bonds, and the absence of crystallinity. Thus, BG 58S-5 wt% Sr was prepared using the alkali-mediated sol-gel process (PA-1M) and characterized as the techniques mentioned in addition to bioactivity and cytotoxicity assays. Both compositions showed the development of a layer of apatite when treated in a simulated body fluid (SBF). Strontium composition showed higher cell viability and more evidence of calcium phosphate formation while calcium carbonate is mainly identified in strontium-free composition.
Alumina is extensively used in the advanced ceramic industry, mainly for mechanical and electronic applications. However, the high melting point of Al
2O
3 necessitates a high sintering temperature ...of around 1923 K. In this work it was investigated the effect of niobium oxide additives on the thermal conductivity of alumina sintered at 1673 K, and at 1723 K. Niobia concentrations added ranged from 1 to 6% in weight. Thermal diffusivity was measured over the temperature range 373–1273 K using the laser flash method. The samples sintered at 1723 K containing ≥ 3% Nb
2O
5 show a continuous microstructure containing little porosity. Nb
2O
5 additions in the range 3–6% result in increases in thermal conductivity, the highest increase being noted for the 5 wt% addition.
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