The effect of sulfide on -glucosidases: implications for starch degradation in anaerobic bioreactors

Membrane associated α-glucosidase activity was investigated in a methanogenic bioreactor (MR) and a biosulfidogenic bioreactor (SR). Temperature and pH optima studies showed temperature optima of 50 °C and pH optima of 8.0 for the α-glucosidases from both the MR and SR. Sulfide (at a concentration of 150 mg l[superscript (−1)]) resulted in the complete loss of all α-glucosidase activity in both the MR and SR. β-Glucosidase activities in our bioreactors were previously shown to be stimulated in the presence of sulfide. α-Glucosidases, in contrast, are inhibited by sulfide. This differential effect of sulfide on α-glucosidase and β-glucosidase activities is highlighted and is of crucial consequence to the respective degradation and utilization of starch and cellulose substrates in natural anaerobic environments and anaerobic bioreactors specifically designed for the accelerated digestion of wastewater sludge under biosulfidogenic conditions

The effect of physico-chemical parameters and chemical compounds on the activity of β-d-galactosidase (B-GAL), a marker enzyme for indicator microorganisms in water

The presence of coliforms in polluted water was determined enzymatically (in situ) by directly monitoring the activity of beta-d-galactosidase (B-GAL) through the hydrolysis of the yellow chromogenic subtrate, chlorophenol red beta-d-galactopyranoside (CPRG), which produced a red chlorophenol red (CPR) product. The objectives of this study were to monitor the effect of compounds commonly found in the environment and used in water treatment on a B-GAL CPRG assay and to investigate the differences between the environmental B-GAL enzyme and the pure commercial enzyme. Environmental B-GAL was optimally active at pH 7.8. Two temperature optima were observed at 35 and 55 degrees C, respectively. B-GAL activity was strongly inhibited by silver and copper ions. While calcium and ferrous ions at lower concentrations (50-100mgl(-1)) increased the enzyme activity, a reduction was observed at higher concentrations (200mgl(-1)). Sodium hypochlorite, normally used in rural areas to disinfect water gradually decreased B-GAL activity at concentrations between 0 and 5600ppm for both the commercial and environmental enzymes. B-GAL from the environment behaved differently from its commercially available counterpart

Comparison of the direct enzyme assay method with the membrane filtration technique in the quantification and monitoring of microbial indicator organisms - seasonal variations in the activities of coliforms and E.coli, temperature and pH

The aim of this project was to monitor variations and relationships between coliform and E. coli counts, the activities of their marker enzymes GAL and GUD, and temperature and pH over a period of 12 months in river samples obtained from the Eastern Cape, South Africa. Several polluted water samples were collected for direct coliform β-D-galactosidase (B-GAL) and Escherichia coli β-D-glucuronidase (B-GUD) assays and the membrane filtration technique. While all the samples showed enzyme activities, not all exhibited growth on CM1046 media. Variation in B-GAL activity (40%) was observed between November (highest activity month) and May (lowest activity month). The highest and lowest B-GUD activities were observed in the months of September and May/June, respectively. The sensitivity of the spectrophotometric assay method was indicated by a limit of detection (LOD) of 1 coliform forming unit (CFU)/100 mℓ and 2 CFU/100 mℓ for coliforms and E. coli, respectively. There was a significant (P < 0.05) positive correlation between E. coli counts and GUD activity (R2 = 0.8909). A correlation of R2 = 0.9151 was also observed between total coliforms and B-GAL activity, even though the CFUs were not evenly distributed. Direct enzyme assays were also shown to be more sensitive than the membrane filtration (MF) technique

A novel biosensor for the detection and monitoring of -d-galactosidase of faecal origin in water

A voltammetric sensor prepared by the immobilization of metallophthalocyanine complexes onto a glassy carbon electrode has been developed for the detection of β-d-galactosidase (B-GAL) of faecal origin in water. Electrooxidation of chlorophenol red, a breakdown product of the chromogenic substrate chlorophenol red β-d-galactopyranoside, was used as a measure of β-d-galactosidase activity. At metallophthalocyanine modified electrodes, in particular copper(II) phthalocyanine, a decrease in electrode fouling was observed. The sensor was sensitive to fluctuations in pH, not significantly affected by temperature variations and could detect one colony forming unit/100 mL in 15 min. Loss of 40% sensitivity was observed over a period of 30 days. A strong correlation between sensor sensitivity and colony forming units was observed. The sensor is capable of detecting viable but nonculturable bacteria, overcoming this drawback of the use of culture media for detection of coliforms

Hodgkin Lymphoma at the Paediatric Oncology Unit of Gabriel Touré Teaching Hospital, Bamako, Mali: 5-Year Experience

Introduction. The aim of this retrospective, unicentric study over 5 years is to describe the epidemiologic, pathologic, clinic and therapeutic aspects of children treated for Hodgkin lymphoma in our paediatric oncology unit. Patients and Methods. From January 2005 to December 2009, all children under 18 years of age, with Hodgkin lymphoma were included in this study. The treatment protocol was the GFAOP (Groupe Franco—Africain d'Oncologie Pédiatrique) Hodgkin lymphoma treatment protocol. Results. During the study period, 217 cancer cases were diagnosed in our centre. Of these cases, 7 were Hodgkin Lymphoma (LH) (0.04%). The mean age was 11.7 years. The sex-ratio was 6/1. 4% (5/7) of patients were stage IIB and 28.6% (2/7) stage IIIB of Ann-Arbor classification. There were 3 cases (42.8%) of sclero-nodular subtype, 2 cases (28.6%) of lymphocyte-rich classical HL subtype, 1 case (14.3%) of mixed cellularity and 1 case (14.3%) of lymphocyte depleted subtype. With a median followup of 37 months, 5 patients (71.4%) are alive, and 2 patients (28.6%) died. Conclusion. Broader multicentric studies are needed for more accurate data on this malignancy

Lymphome de Burkitt pédiatrique à révélation orl : quelle prise en charge en milieu sub sahélien ? réflexion sur trois cas

Le lymphome de Burkitt dans sa forme Africaine peut se manifester sous des signes d’emprunt ORL à type de tuméfaction orbito-maxillo-faciale. Le diagnostic peut être fait par les ORL à travers un faisceau de signes cliniques et une cytoponction. La prise en charge se fait dans des unités d’oncologie médicale ou le bilan d’extension et le lancement de la chimiothérapie sont des impératifs incontournables. Actuellement cette tumeur à potentiel très agressif répond à une poly chimiothérapie bien conduite.Mots-clés : Lymphome de Burkitt, cancer, voies aérodigestives supérieures, oncologie pédiatriqu

Dietary patterns and changes in body composition in children between 9 and 11 years

Objective: Childhood obesity is rising and dietary intake is a potentially modifiable factor that plays an important role in its development. We aim to investigate the association between dietary patterns, obtained through principal components analysis and gains in fat and lean mass in childhood. Design : Diet diaries at 10 years of age collected from children taking part in the Avon Longitudinal Study of Parents and Children. Body composition was assessed using dual-energy X-ray absorptiometry at 9 and 11. Setting: Longitudinal birth cohort. Subjects: 3911 children with complete data. Results: There was an association between the Health Aware (positive loadings on high-fiber bread, and fruits and vegetables; negative loadings on chips, crisps, processed meat, and soft drinks) pattern score and decreased fat mass gain in girls. After adjusting for confounders, an increase of 1 standard deviation (sd) in this score led to an estimated 1.2% decrease in fat mass gain in valid-reporters and 2.1% in under-reporters. A similar decrease was found only in under-reporting boys. There was also an association between the Packed Lunch (high consumption of white bread, sandwich fillings, and snacks) pattern score and decreased fat mass gain (1.1% per sd) in valid-reporting but not under-reporting girls. The main association with lean mass gain was an increase with Packed Lunch pattern score in valid-reporting boys only. Conclusions: There is a small association between dietary patterns and change in fat mass in mid-childhood. Differences between under- and valid-reporters emphasize the need to consider valid-reporters separately in such studies. © 2014 Andrew D. A. C. Smith et al

Prospect for Charge Current Neutrino Interactions Measurements at the CERN-PS

Tensions in several phenomenological models grew with experimental results on neutrino/antineutrino oscillations at Short-Baseline (SBL) and with the recent, carefully recomputed, antineutrino fluxes from nuclear reactors. At a refurbished SBL CERN-PS facility an experiment aimed to address the open issues has been proposed [1], based on the technology of imaging in ultra-pure cryogenic Liquid Argon (LAr). Motivated by this scenario a detailed study of the physics case was performed. We tackled specific physics models and we optimized the neutrino beam through a full simulation. Experimental aspects not fully covered by the LAr detection, i.e. the measurements of the lepton charge on event-by-event basis and their energy over a wide range, were also investigated. Indeed the muon leptons from Charged Current (CC) (anti-)neutrino interactions play an important role in disentangling different phenomenological scenarios provided their charge state is determined. Also, the study of muon appearance/disappearance can benefit of the large statistics of CC muon events from the primary neutrino beam. Results of our study are reported in detail in this proposal. We aim to design, construct and install two Spectrometers at "NEAR" and "FAR" sites of the SBL CERN-PS, compatible with the already proposed LAr detectors. Profiting of the large mass of the two Spectrometers their stand-alone performances have also been exploited.Comment: 70 pages, 38 figures. Proposal submitted to SPS-C, CER

Bulk Etch Rate Measurements and Calibrations of Plastic Nuclear Track Detectors

New calibrations of CR39 and Makrofol nuclear track detectors have been obtained using 158 A GeV Pb (82+) and In (49+) ions; a new method for the bulk etch rate determination, using both cone height and base diameter measurements was developed. The CR39 charge resolution based on the etch-pit base area measurement is adequate to identify nuclear fragments in the interval 7 <= Z/beta <= 49. For CR39 the detection threshold is at REL~50 MeV cm^2/g, corresponding to a nuclear fragment with Z/beta~7. Base cone area distributions for Makrofol foils exposed to Pb (82+) ions have shown for the first time all peaks due to nuclear fragments with Z > 50; the distribution of the etched cone heights shows well separated individual peaks for Z/beta = 78 - 83 (charge pickup). The Makrofol detection threshold is at REL 2700 MeV cm^2/g, corresponding to a nuclear fragment with Z/beta~50.Comment: 11 pages, 5 EPS figures. Submitted to Nucl. Instr. Meth.