45 research outputs found
Effect of phosphorus on the attenuation of lead and chromium
This study analyses the adsorption of Pb(II) and Cr(III) in soils. These metals are commonly found together in nature in urban wastes or industrial spillages, and the theoretical approach of the work was to evaluate the response of the soil to continuous Cr and Pb spillages to soil in terms of several physicochemical parameters. The influence of an anthropogenic input of phosphorus was evaluated. Continuous flow experiments were run in duplicates in acrylic columns (25 cm Ă 3.2 cm). The influent Cr(III) and Pb(II) solutions of 10 mg lâ1 and 25 mg lâ1 at pH 5 were pumped upward through the bottom of the columns to ensure saturation flow conditions. Also, successive experiments were run with the above concentrations of Cr(III) and Pb(II) and NaH2PO4, keeping metal to phosphorus ratio of 1:0, 1:0.1 and 1:1. Modelling parameters included Freundlich and Langmuir equations, together with the Two-site adsorption model using CXTFIT code. Results obtained allowed concluding that Pb(II) adsorption presents a certain degree of irreversibility and the continued spillages over soil increment the fraction which is not easily desorbed. Cr(III) desorption was almost complete, evidencing its high mobility in nature. The presence of an anthropogenic input of phosphorus leads to a marked increase of both Pb(II) and Cr(III) adsorption in soils. Z-potential measurements allow to discard the electrostatic attraction of Cr(III) and Pb(II) with the surface charged soil as the dominant process of metal sorption. Instead, CheaqsPro simulation allows to identify PbH2PO4 +, PbHPO4 (aq) and CrHPO4 + as the dominant species which regulate Cr(III) and Pb(II) transport in soils.Fundação para a CiĂȘncia e a Tecnologi
High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis
Collagen synthesis is severely diminished in osteoarthritis; thus, enhancing it may help the regeneration of cartilage. This
requires large amounts of glycine, proline and lysine. Previous works of our group have shown that glycine is an essential
amino acid, which must be present in the diet in large amounts to satisfy the demands for collagen synthesis. Other authors
have shown that proline is conditionally essential. In this work we studied the effect of these amino acids on type II collagen
synthesis. Bovine articular chondrocytes were cultured under a wide range of different concentrations of glycine, proline and
lysine. Chondrocytes were characterized by type II collagen immunocytochemistry of confluence monolayer cultures. Cell
growth and viability were assayed by trypan blue dye exclusion method. Type II collagen was measured in the monolayer,
every 48 h for 15 days by ELISA. Increase in concentrations of proline and lysine in the culture medium enhances the synthesis
of type II collagen at low concentrations, but these effects decay before 1.0 mM. Increase of glycine as of 1.0 mM
exceeds these effects and this increase continues more persistently by 60â75%. Since the large effects produced by proline
and lysine are within the physiological range, while the effect of glycine corresponds to a much higher range, these results
demonstrated a severe glycine deficiency for collagen synthesis. Thus, increasing glycine in the diet may well be a strategy
for helping cartilage regeneration by enhancing collagen synthesis, which could contribute to the treatment and prevention
of osteoarthriti
A proposed new bacteriophage subfamily: âJerseyvirinaeâ
© 2015, Springer-Verlag Wien. Based on morphology and comparative nucleotide and protein sequence analysis, a new subfamily of the family Siphoviridae is proposed, named âJerseyvirinaeâ and consisting of three genera, âJerseylikevirusâ, âSp3unalikevirusâ and âK1glikevirusâ. To date, this subfamily consists of 18 phages for which the genomes have been sequenced. Salmonella phages Jersey, vB_SenS_AG11, vB_SenS-Ent1, vB_SenS-Ent2, vB_SenS-Ent3, FSL SP-101, SETP3, SETP7, SETP13, SE2, SS3e and wksl3 form the proposed genus âJerseylikevirusâ. The proposed genus âK1glikevirusâ consists of Escherichia phages K1G, K1H, K1ind1, K1ind2 and K1ind3. The proposed genus âSp3unalikevirusâ contains one member so far. Jersey-like phages appear to be widely distributed, as the above phages were isolated in the UK, Canada, the USA and South Korea between 1970 and the present day. The distinguishing features of this subfamily include a distinct siphovirus morphotype, genomes of 40.7-43.6kb (49.6-51.4mol% G+C), a syntenic genome organisation, and a high degree of nucleotide sequence identity and shared proteins. All known members of the proposed subfamily are strictly lytic
Assessment of thrombin-activatable fibrinolysis inhibitor (TAFI) activation in acquired hemostatic dysfunction: a diagnostic challenge
ATP-binding cassette (ABC) transporters in normal and pathological lung
ATP-binding cassette (ABC) transporters are a family of transmembrane proteins that can transport a wide variety of substrates across biological membranes in an energy-dependent manner. Many ABC transporters such as P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and breast cancer resistance protein (BCRP) are highly expressed in bronchial epithelium. This review aims to give new insights in the possible functions of ABC molecules in the lung in view of their expression in different cell types. Furthermore, their role in protection against noxious compounds, e.g. air pollutants and cigarette smoke components, will be discussed as well as the (mal)function in normal and pathological lung. Several pulmonary drugs are substrates for ABC transporters and therefore, the delivery of these drugs to the site of action may be highly dependent on the presence and activity of many ABC transporters in several cell types. Three ABC transporters are known to play an important role in lung functioning. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene can cause cystic fibrosis, and mutations in ABCA1 and ABCA3 are responsible for respectively Tangier disease and fatal surfactant deficiency. The role of altered function of ABC transporters in highly prevalent pulmonary diseases such as asthma or chronic obstructive pulmonary disease (COPD) have hardly been investigated so far. We especially focused on polymorphisms, knock-out mice models and in vitro results of pulmonary research. Insight in the function of ABC transporters in the lung may open new ways to facilitate treatment of lung diseases