<Emphasis Type="Italic">In vitro</Emphasis> organogenesis of <Emphasis Type="Italic">Passiflora alata</Emphasis>

Passiflora alata in vitro organogenesis was studied based on explant type, culture medium composition, and incubation conditions. The results indicated that the morphogenic process occurred more efficiently when hypocotyl segment-derived explants were cultured in media supplemented with cytokinin and AgNO₃ incubated under a 16-h photoperiod. The shoot bud elongation and plant development were obtained by transferring the material to MSM culture medium supplemented with GA₃ and incubated in flasks with vented lids. Histological analyses of the process revealed that the difficulties in obtaining plants could be related to the development of protuberances and leaf primordia structures, which did not contain shoot apical meristem. Roots developed easily by transferring elongated shoots to 1/2 MSM culture medium. Plant acclimatization occurred successfully, and somaclonal variation was not visually detected. The efficiency of this organogenesis protocol will be evaluated for genetic transformation of this species to obtain transgenic plants expressing genes that can influence the resistance to Cowpea aphid borne mosaic virus.     

The impact of cold-water immersion on power production in the vertical jump and the benefits of a dynamic exercise warm-up

The purpose of this study was to examine the influence of a cold treatment and a dynamic warm-up on lower body power in the form of a countermovement vertical jump (CMVJ). Nine physically active men, who were either current or ex-National Collegiate Athletic Association (NCAA) Division 1 athletes, consented to participate in the study. Using a balanced, randomized presentation and a within-subject design, each subject performed 4 environmental and warm-up protocols (i.e., ambient temperature without warm-up, ambient temperature with warm-up, cold without warm-up, or cold with warm-up). Two sets of 3 maximal effort CMVJs were performed on a force plate at each testing time point. For each protocol, the subjects completed a pretest set of CMVJ (pretreatment [PRE]), were then exposed to 1 of the 2 temperature treatments, completed another set of CMVJ (initial [IT]), then either went through a 15-minute warm-up, or were asked to sit in place. Then a final set of CMVJs was completed (posttreatment [PT]). The primary finding in this study was that warm-up was effective in offsetting the negative effects of cold exposure on CMVJ power. There was a significant main effect for Time (PRE > PT > IT), and there was a significant (p ≤ 0.05) main effect for Trial (AMB = AMBWU > COLDWU > COLD). Because athletic competitions happen in various colder climates, it is important to make sure that a proper warm-up be completed to maximize the athlete's power output. The results of this study demonstrate that when athletes are exposed to cold conditions, it is recommended that before practice or play, a dynamic warm-up be employed to optimize performance.     

Purification and characterization of the α-glucosidase produced by thermophilic fungus <Emphasis Type="Italic">Thermoascus aurantiacus</Emphasis> CBMAI 756

An α-glucosidase enzyme produced by the fungus Thermoascus aurantiacus CBMAI 756 was purified by ultra filtration, ammonium sulphate precipitation, and chromatography using Q Sepharose, Sephacryl S-200, and Superose 12 columns. The apparent molecular mass of the enzyme was 83 kDa as determined in gel electrophoresis. Maximum activity was observed at pH 4.5 at 70°C. Enzyme showed stability stable in the pH range of 3.0–9.0 and lost 40% of its initial activity at the temperatures of 40, 50, and 60°C. In the presence of ions Na⁺, Ba²⁺, Co²⁺, Ni²⁺, Mg²⁺, Mn²⁺, Al³⁺, Zn²⁺, Ca²⁺ this enzyme maintained 90–105% of its maximum activity and was inhibited by Cr³⁺, Ag⁺, and Hg²⁺. The enzyme showed a transglycosylation property, by the release of oligosaccharides after 3 h of incubation with maltose, and specificity for short maltooligosaccharides and α-PNPG. The K_m measured for the α-glucosidase was 0.07 μM, with a V_max of 318.0 μmol/min/mg.     

Promotion of human adipose‐derived stem cell proliferation mediated by exogenous nucleosides

Adult stem cells are becoming the best option for regenerative medicine because they have low tumourigenic potential and permit autologous transplantation, even without in vitro culture. Our objectives were to evaluate the effects of exogenous nucleosides on the proliferation of hASCs (human adipose‐derived stem cells), with or without co‐treatment with 5‐aza (5‐azacytidine), and to analyse the expression of lamin A/C during cardiomyocyte differentiation of these cells. We isolated hASCs from human lipoaspirates that were positive for mesenchymal stem cell markers. We found that 5‐aza induces a dose‐dependent inhibition of hASC proliferation [IC50 (inhibitory concentration 50): 5.37 μM], whereas exogenous nucleosides significantly promote the proliferation of hASCs and partially revert the antiproliferative effect of the drug. Multipotentiality of isolated hASCs was confirmed by adipogenic, osteogenic and cardiomyogenic induction. 5‐Aza‐induced cells expressed cardiac troponins I and T and myosin light chain 2, myocardial markers that were directly correlated with lamin A/C expression. Our results support the importance of the nucleoside supplementation of media to improve conditions for the expansion and maintenance of hASCs in culture. In addition, the quantification of lamin A/C expression appears to be a good marker for the characterization of cardiomyocyte differentiation of stem cells that has rarely been used.     

Comparison of Humanized IgG and FvFc Anti-CD3 Monoclonal Antibodies Expressed in CHO Cells

Two humanized monoclonal antibody constructs bearing the same variable regions of an anti-CD3 monoclonal antibody, whole IgG and FvFc, were expressed in CHO cells. Random and site-specific integration were used resulting in similar expression levels. The transfectants were selected with appropriate selection agent, and the surviving cells were plated in semi-solid medium for capture with FITC-conjugated anti-human IG antibody and picked with the robotic ClonePix FL. Conditioned media from selected clones were purified by affinity chromatography and characterized by SDS-PAGE, Western-blot, SEC-HPLC, and isoelectric focusing. Binding to the target present in healthy human mononuclear cells was assessed by flow cytometry, as well as by competition between the two constructs and the original murine monoclonal antibody. The humanized constructs were not able to dislodge the murine antibody while the murine anti-CD3 antibody could dislodge around 20% of the FvFc or IgG humanized versions. Further in vitro and in vivo pre-clinical analyses will be carried out to verify the ability of the humanized versions to demonstrate the immunoregulatory profile required for a humanized anti-CD3 monoclonal antibody.     

Valorization of Foundry Sand in Clay Bricks at Industrial Scale

In this article, foundry sand as waste material has been valorized in ceramic brick manufacturing at industrial scale. The employment of a waste coming from one industry as an input for another is one of the key concepts of industrial ecology. To study the environmental behavior of the ceramic bodies in different life cycle stages, three leaching tests have been developed. We used an EN 12457 equilibrium leaching test with distilled water and a Wastewater Technology Centre acid neutralization capacity (WTC‐ANC) leaching test with different acidic leachates to carry out the environmental evaluation under different granular scenarios to ascertain the possibilities of the reuse or disposal of this granular material at the end of its useful life (end‐of‐life stage). Finally, we used a NEN 7345 diffusion leaching test for construction materials, with the aim of studying the environmental assessment at the use stage. Regulated pollutants in both stages have been evaluated. Furthermore, other soluble salts have been analyzed because they are closely related to the efflorescence phenomenon in bricks. Results indicate that core and green sand from the foundry industry can be used to replace clay content in construction materials, and that these foundry‐sand‐based ceramics improve some soluble salt results. Despite this fact, at the end‐of‐life stage in an inert waste landfill, lead, arsenic and chromium can be an environmental problem, both for commercial bricks and for foundry‐sand‐based bricks. This work can contribute to the determination of viability of sustainable processes of brick manufacturing that use foundry wastes as raw materials.     

Identification of a new hexadentate iron chelator capable of restricting the intramacrophagic growth of Mycobacterium avium

Iron accumulation has been suggested to contribute to an increase of the susceptibility to mycobacterial infections. In this study we tested the effect of an array of iron chelating ligands of the 3-hydroxy-4-pyridinone family, in the intramacrophagic growth of Mycobacterium avium. We found that bidentate chelators, namely N-alkyl-3-hydroxy-4-pyridinones and N-aryl-3-hydroxy-4-pyridinones, did not affect the growth of M. avium inside mouse macrophages. In the case of the hexadentate chelators, those synthesized using an alkylamine (CP262) or a benzene ring (CP252) to link the three bidentate units, did not have an inhibitory effect on intramacrophagic growth of M. avium while those synthesized from a tripodal structure to anchor the bidentate units were capable of inhibiting the intramacrophagic growth of M. avium. The molecule we designated CP777 had the strongest inhibitory activity. The growth-reducing activity of CP777 was abrogated when this molecule was saturated with iron. These results confirm that iron deprivation, by the use of iron chelating compounds, restricts M. avium growth and that new iron chelators offer an approach to controlling mycobacterial infections.     

Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin

doi:10.1111/j.1741‐2358.2009.00292.x
Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin Objective: In this study, the effect of relining and surface treatment on the impact strength (IS) of a heat‐polymerising denture base acrylic resin (Lucitone 550‐L) was evaluated. Materials and methods: Rectangular bars of L were made (60 × 6 × 2 mm) and relined (2 mm) with the relining resins Ufi Gel Hard (UH) and Tokuso Rebase Fast (TR). Specimens relined with L and intact L, TR and UH specimens were also made (60 × 6 × 4 mm), for comparison. Before relining, the L surface was left untreated or wetted with methyl methacrylate monomer and/or the bonding agents (BA) supplied by manufacturers of the reline resins. V‐notches were machined at the midpoint of the length of all specimens. The notches were made either across the width (Nw) or across the thickness of the specimens (Nth). The Charpy impact test was performed using a 0.5‐J pendulum, which had been specially designed and constructed. Data were analysed separately for each notch position using one‐way analysis of variance and Tukey honestly significant difference post‐hoc test (p = 0.05). Results: The IS of L was similar to that of L/L. For the Nw notch, treating the denture base L with TR BA and relining with TR reline material produced the highest IS. Conclusion: The IS of specimens made from heat polymerising acrylic resin Lucitone 550 was increased after relining using the hard chairside reline resin TR with its proprietary BA.