Biorefinery of rice husk to obtain functionalized bioactive compounds

The biomass industrialization valorisation of grains and cereals is considered an opportunity for the countries where agro-industrial activity is one of its main economic activities, rendering new higher-value products with a concomitant solution to waste accumulation issues. To that end, in this work we describe and characterise bioactive compounds generation from rice husk by semisolid fermentation, obtained from 500 g of the material at room temperature and 60% humidity with mixed cultures of Phanerochaete chrysosporium and Gloeophyllum trabeum. The extract was evaluated in different situations: murine mammary tumour cells (4T1), normal cells (NIH 3T3) and in Lactobacillus acidophilus, and Trichoderma harzianum. The results exhibited that the extract inhibited 4T1 cells at concentrations higher than 20μg/mL, but did not inhibit normal cells, and displayed germicide activity after 3 days incubations. We propose that these functionalized compounds have a potential application in industry/agriculture/medicine obtained from rice husk waste

Long-term Results of Totally Laparoscopic Aortobifemoral Bypass

OBJECTIVES: The aim was to estimate the long-term results and patency rates of totally laparoscopic aortobifemoral bypass in aorto-iliac occlusive disease (AIOD). METHODS: All 87 patients who received a laparoscopic aortobifemoral bypass for AIOD on an intention to treat basis between October 2003 and October 2013 were identified. All operations were performed by the same surgical team using a totally laparoscopic technique. Demographic, pre-operative, peri-operative, and follow up variables were collected and analyzed. Patients were followed up at 1 month post-operatively and annually thereafter. Patency rates were calculated in accordance with published patency reporting standards. RESULTS: The median age was 57 years (range 40-78 years). The conversion rate was 20.6% overall. The thirty-day post-operative mortality was 1.1%. Six patients required early re-intervention. There were no graft infections. The median length hospital stay was 6 days (range 4-39 days). The mean follow up was 58.0 months (range 1-133 months). Graft limb based primary, primary assisted, and secondary patency rates were respectively 96.1%, 98.1% and 99.4% at 1 year, and 83.0%, 92.0% and 97.0% at 5 years. CONCLUSION: Totally laparoscopic aortobifemoral bypass is a safe alternative to open surgery in selected patients, with excellent long-term patency rates, albeit at the cost of a steep learning curve.status: publishe

Polymerase-chain-reaction-based semi-quantification of hepatitis D viraemia in patients treated with high doses of alpha 2b interferon

To study the antiviral efficacy of high doses of alpha 2b interferon (alpha 2b-IFN) for chronic hepatitis D treatment, we used polymerase-chain-reaction(PCR)-based semi-quantitative detection of HDV RNA. The semi-quantification method used was based on the appearance of a positive amplification signal as a function of the number of PCR cycles. By amplifying dilutions (10(-1)-10(-8)) of an HDV-positive woodchuck liver RNA, we confirmed that exponential amplification efficacy occurred at between 20 and 30 cycles. Positive signals were observed from dilution 10(-2) (gel electrophoresis after 20 cycles of PCR) to dilution 10(-7) (hybridization after 30 cycles of PCR). To characterize the HDV RNA level in sera of 8 patients treated with alpha 2b-IFN (10 MU/3 times a week) for 1 year, we extracted RNA from serum samples taken every 6 months. All samples were amplified in parallel for 20 and 30 PCR cycles. Analysis of HDV cDNA after ethidium bromide/agarose gel electrophoresis and after molecular hybridization (100 times more sensitive than gel analysis), enabled us to grade the signals observed from negative to positive as 1+, 2+, 3+ and 4+, with all results being positive. Three types of evolution of HDV viraemia were evidenced among the 8 treated patients. HDV replication continued to occur at a high level at the 6th and 12th month in 2 patient sera. For 2 other patients, an HDV RNA decrease or disappearance was evidenced in the serum at the 6th month; however, viral replication recurred at a higher level at the 12th month.(ABSTRACT TRUNCATED AT 250 WORDS

Arrangement of Monofunctional Silane Molecules on Silica Surfaces: Influence of Alkyl Chain Length, Head-Group Charge, and Surface Coverage, from Molecular Dynamics Simulations, X-ray Photoelectron Spectroscopy, and Fourier Transform Infrared Spectroscopy

International audienceSurface chemical functionalization is used in analytical tools to immobilize biomolecules that will capture a specific analyte and also to reduce the nonspecific adsorption. Silane monolayers are widely used to functionalize silica surfaces. Their interfacial properties are linked to the silane organization. Here, we study, by molecular dynamics simulations, the effects of silane molecule head-group charge, alkyl chain length, and surface coverage on the structure of silane monolayers. Four molecules are investigated: 3-aminopropyldimethylethoxysilane, n-propyldimethylmethoxysilane, octadecyldimethylmethoxysilane, and tert-butyl-11-(dimethylamino(dimethyl)silyl)undecanoate. The results suggest that, while long alkyl chains straighten out and adopt a more organized structure as surface coverage increases, the tilt angle of short chains is independent of surface coverage. Furthermore, in the case of long alkyl chains, a charged head-group seems to reduce the tilt angle to surface coverage dependence. The simulated alkyl chain tilt angles were qualitatively validated by infrared spectroscopy and X-ray photoelectron spectroscopy. Also, a hexagonal packing is observed in all of the monolayers but is more defined as surface coverage increases. The nematic order parameter suggests that this packing is governed by the parallel orientation of the first C–C bonds near the surface. So, even short alkyl chains, with a large tilt angle distribution, present a hexagonal packing