Calcined Hydroxyapatite with Collagen I Foam Promotes Human MSC Osteogenic Differentiation

Collagen I-based foams were modified with calcined or noncalcined hydroxyapatite or calcium phosphates with various particle sizes and pores to monitor their effect on cell interactions. The resulting scaffolds thus differed in grain size, changing from nanoscale to microscopic, and possessed diverse morphological characteristics and resorbability. The materials’ biological action was shown on human bone marrow MSCs. Scaffold morphology was identified by SEM. Using viability test, qPCR, and immunohistochemical staining, we evaluated the biological activity of all of the materials. This study revealed that the most suitable scaffold composition for osteogenesis induction is collagen I foam with calcined hydroxyapatite with a pore size of 360 ± 130 µm and mean particle size of 0.130 µm. The expression of osteogenic markers RunX2 and ColI mRNA was promoted, and a strong synthesis of extracellular protein osteocalcin was observed. ColI/calcined HAP scaffold showed significant osteogenic potential, and can be easily manipulated and tailored to the defect size, which gives it great potential for bone tissue engineering applications.     

Myo-inositol hexakisphosphate degradation by Bifidobacterium infantis ATCC 15697

The ability of five strains of different bifidobacterial species (Bifidobacterium animalis, B. bifidum, B. infantis, B. longum, B. pseudolongum) isolated from human and animal gut to degrade myo-inositol hexaphosphate or phytic acid (InsP(6)) has been evaluated. The disappearance of phytate and the generation of lower myo-inositol phosphates were determined in a complex medium in which phytic acid was the only source of phosphorus. Bifidobacterium infantis ATCC 15697 showed the highest level of phytate-degrading activity. This strain displayed optimal activity at slight acid pH (6.0-6.5) and 50 degrees C, but also retained high activity levels at neutral pH and 37 degrees C. B. infantis ATCC 15697 produced maximum activity during the stationary phase of growth and when 1% lactose was used as carbon source. In contrast, the presence of inorganic phosphate in the growth medium inhibited phytase activity. The ability of B. infantis ATCC 15697 to generate lower myo-inositol phosphates and, particularly, accumulate myo-inositol tri-phosphates (InsP(3)) from partial hydrolysis of InsP(6) could contribute to the reduction of the anti-nutritional properties of InsP(6) and the generation of intermediate compounds with beneficial properties during food processing and gastrointestinal transit.     

Modeling of coupled mass and heat transfer through venting membranes for automotive applications

Experimental and theoretical approaches based on a mathematical model, have been developed to study the evolution of environmental parameters (temperature, total pressure, relative humidity, and water vapor partial pressure) inside a housing of an electronic device with a window containing a macroporous membrane. The model was based on the coupling of mass and heat transfer taking into account the effects of polarization of concentration in boundary layers. Membranes have been characterized by mercury porosimetry, liquid entry pressure measurements, scanning electron microscopy, and gas permeation. Once the model was experimentally validated, it was applied to investigate the influence of membranes on heat and mass transfer and to study the impact of the boundary layers on the global mass transport. The results demonstrated the importance of the membrane choice and dimensions to get the best temperature regulation and avoid water condensation inside an automotive electronic control unit (ECU). © 2008 American Institute of Chemical Engineers AIChE J, 2009     

Babesia Bovis Ligand-Receptor Interaction: AMA-1 Contains Small Regions Governing Bovine Erythrocyte Binding

Apical membrane antigen 1 is a microneme protein which plays an indispensable role during Apicomplexa parasite invasion. The detailed mechanism of AMA-1 molecular interaction with its receptor on bovine erythrocytes has not been completely defined in Babesia bovis. This study was focused on identifying the minimum B. bovis AMA-1-derived regions governing specific and high-affinity binding to its target cells. Different approaches were used for detecting ama-1 locus genetic variability and natural selection signatures. The binding properties of twelve highly conserved 20-residue-long peptides were evaluated using a sensitive and specific binding assay based on radio-iodination. B. bovis AMA-1 ectodomain structure was modelled and refined using molecular modelling software. NetMHCIIpan software was used for calculating B- and T-cell epitopes. The B. bovis ama-1 gene had regions under functional constraint, having the highest negative selective pressure intensity in the Domain I encoding region. Interestingly, B. bovis AMA-1-DI (¹⁰⁰YMQKFDIPRNHGSGIYVDLG¹¹⁹ and ¹²⁰GYESVGSKSYRMPVGKCPVV¹³⁹) and DII (³⁰²CPMHPVRDAIFGKWSGGSCV³²¹)-derived peptides had high specificity interaction with erythrocytes and bound to a chymotrypsin and neuraminidase-treatment sensitive receptor. DI-derived peptides appear to be exposed on the protein’s surface and contain predicted B- and T-cell epitopes. These findings provide data (for the first-time) concerning B. bovis AMA-1 functional subunits which are important for establishing receptor-ligand interactions which could be used in synthetic vaccine development.     

Effect of frying various legumes under optimum conditions on amino acids,in vitro protein digestibility,phytate and oligosaccharides

The effects of optimum conditions of frying soybean, broad bean and Polish pea on proximate analysis and amino acid composition were investigated. Maximum water absorption of 192.93, 129.05 and 148.68% for soybean, broad bean and Polish pea was reached after soaking periods of 16.41, 17.84 and 16.45 h respectively. Sensory evaluation of different temperatures (150, 170 and 190 °C) and frying times (5, 10 and 15 min) for preparing soybean, broad bean and Polish pea indicated that there was a significant difference (P < 0.01) between treatments. The most acceptable fried soybean, broad bean or Polish pea was obtained after frying at 190 °C for 5 min. All the processed legumes under investigation had higher protein digestibility as measured in vitro and minimum reduction in total amino acid composition. The optimum frying process is an effective method for lowering phytate content (myo‐inositol hexaphosphate) by 89.77, 67.70 and 82.88% respectively as well as causing considerable loss of total oligosaccharides by 64.35, 16.16 and 49.44%. © 2000 Society of Chemical Industry     

Evolution of soluble carbohydrates during the development of pea, faba bean and lupin seeds

Seeds of pea (Pisum sativum L. cv. Ergo), faba bean (Vicia faba ssp. minor Harz., cv. Tibo) and yellow pea lupin (Lupinus luteus L. cv. Juno) were sampled at different days after flowering (DAF) and their content of soluble carbohydrates was determined: Analysis of samples showed thatmyo-inositol, fructose, glucose, galactose and sucrose were found in high abundance early in development and their content decreased gradually during maturation. -Galactosides, which includes the content of raffinose, stachyose and verbascose, started to appear later in seed development, at 37 DAF in peas, 40 DAF in faba beans and 45 DAF in lupins. Their accumulation increased considerably during seed growth, and the maximum content was obtained in mature seeds; 3.8% in peas, 4.5% in faba beans and 10.4% in lupins. Results obtained for these sugars during seed development were fitted to modelling curves in order to predict sugar content at different development stages.     

Cancer-associated expression of glycolipid sulfotransferase gene in human renal cell carcinoma cells

Human renal cell carcinoma (RCC) tissue and a cell line derived therefrom, SMKT-R3, showed markedly increased glycolipid sulfotransferase [cerebroside sulfotransferase (CST); EC 2.8.2.11] activity and accumulated sulfoglycolipids. Recently, we cloned a human CST cDNA from a SMKT-R3 cDNA library (K. Honke et al., J. Biol. Chem., 272: 4864-4868, 1997). In this study, we investigated the expression of the CST gene in seven human RCC lines (SMKT-R1, SMKT-R2, SMKT-R3, SMKT-R4, TOS-1, TOS-2, and ACHN) and their normal counterpart, human renal proximal tubular cells. On Northern blot analysis, a marked increase of CST mRNA was observed in every RCC line, except for ACHN, as compared with normal cells. ACHN cells showed a slightly increased level of CST mRNA. CST activity was correlated with the amount of mRNA. Sulfoglycolipid analysis revealed that expression of lactosylceramide sulfate was correlated with the CST level. Furthermore, we examined the effects of epidermal growth factor (EGF), tetradecanoylphorbol-13-acetate, and genistein, which are known to regulate CST activity in SMKT-R3 cells, on CST-gene expression in various RCC cells. On treatment with EGF, CST mRNA time-dependently increased in accord with its activity in SMKT-R3 cells. Yet, augmentation by EGF was only observed in SMKT-R3. In contrast, a reduction of CST mRNA and activity by tetradecanoylphorbol-13-acetate and genistein was observed in all of the lines examined. Taken together, these findings indicate that in human RCC cells, the CST gene is generally overexpressed via a signaling pathway involving protein kinase-C and tyrosine kinases.     

Changes in quantities of inositol phosphates during maturation and germination of legume seeds

 The changes in the quantities of inositol phosphates during the maturation and germination of pea, faba bean and lupin seeds were determined in two consecutive (1993 and 1994) years of differing weather conditions. Irrespective of the year, all seeds accumulated predominantly inositol hexaphosphate (IP₆). The weather conditions influenced the accumulation of inositol phosphates in maturing seeds, but they did not influence the total content. Gradual degradation of inositol phosphates occurred during seed germination. After 8 days of germination, IP₆ was degraded by some 80% in peas, 78% in faba beans and 42% in lupin seeds. The enzymic hydrolysis of higher forms of inositol phosphates (IP₆ and IP₅) in germinating seeds was assumed to yield inositol tetraphosphate (IP₄) and inositol triphosphate (IP₃), because the quantities of these compounds increased during seed germination. Received: 1 August 1997 / Revised version: 13 October 1997     

Natural Fermentation of Lentils: Influence of Time,Concentration and Temperature on the Kinetics of Hydrolysis of Inositol Phosphates

Lentil (Lens culinaris var vulgaris) flour was naturally fermented for 96 h at various conditions of concentration (79, 150 and 221 g litre⁻¹) and temperature (28°C, 35°C and 42°C). The content of total inositol phosphates (IP-total) and individual inositol phosphates (hexa- (IP₆), penta- (IP₅), tetra- (IP₄) and tri- (IP₃) phosphates) were analysed to establish the changes of these compounds during natural fermentation of lentils. The preparation of the lentil suspension brought about 16–27% reduction of the total inositol phosphates. At the end of 96 h of natural fermentation maximum IP loss (70–75%) was achieved for an experiment carried out at minimum concentration. For IP₆, the largest decrease was achieved at the highest temperature, the fermentation condition that also brought about the highest IP₅ content.