Antimicrobial effect of different herbal plant extracts against different microbial population

This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).     

Characterization of α-mannosidase from Erythrina indica seeds and influence of endogenous lectin on its activity

α-mannosidase from Erythrina indica seeds is a Zn²⁺ dependent glycoprotein with 8.6% carbohydrate. The enzyme has a temperature optimum of 50 °C and energy of activation calculated from Arrhenius plot was found to be 23 kJ mol^− 1. N-terminal sequence up to five amino acid residues was found to be DTQEN (Asp, Thr, Gln, Glu, and Asn). In chemical modification studies treatment of the enzyme with NBS led to total loss of enzyme activity and modification of a single tryptophan residue led to inactivation. Fluorescence studies over a pH range of 3–8 have shown tryptophan residue to be in highly hydrophobic environment and pH change did not bring about any appreciable change in its environment. Far-UV CD spectrum indicated predominance of α-helical structure in the enzyme. α-Mannosidase from E indica exhibits immunological identity with α-mannosidase from Canavalia ensiformis but not with the same enzyme from Glycine max and Cicer arietinum. Incubation of E. indica seed lectin with α-mannosidase resulted in 35% increase in its activity, while no such activation was observed for acid phosphatase from E. indica. Lectin induced activation of α-mannosidase could be completely abolished in presence of lactose, a sugar specific for lectin.     

Purification of immature neuronal cells from neural stem cell progeny

Large-scale proliferation and multi-lineage differentiation capabilities make neural stem cells (NSCs) a promising renewable source of cells for therapeutic applications. However, the practical application for neuronal cell replacement is limited by heterogeneity of NSC progeny, relatively low yield of neurons, predominance of astrocytes, poor survival of donor cells following transplantation and the potential for uncontrolled proliferation of precursor cells. To address these impediments, we have developed a method for the generation of highly enriched immature neurons from murine NSC progeny. Adaptation of the standard differentiation procedure in concert with flow cytometry selection, using scattered light and positive fluorescent light selection based on cell surface antibody binding, provided a near pure (97%) immature neuron population. Using the purified neurons, we screened a panel of growth factors and found that bone morphogenetic protein-4 (BMP-4) demonstrated a strong survival effect on the cells in vitro, and enhanced their functional maturity. This effect was maintained following transplantation into the adult mouse striatum where we observed a 2-fold increase in the survival of the implanted cells and a 3-fold increase in NeuN expression. Additionally, based on the neural-colony forming cell assay (N-CFCA), we noted a 64 fold reduction of the bona fide NSC frequency in neuronal cell population and that implanted donor cells showed no signs of excessive or uncontrolled proliferation. The ability to provide defined neural cell populations from renewable sources such as NSC may find application for cell replacement therapies in the central nervous system.     

Seed and forage yield,and forage quality determinants of nine legume shrubs in a non-tropical dryland environment

The objective was to identify legume shrub species for development of agroforestry technologies based on seed and forage (leaves and twigs < 10 mm diameter) yield, and determinants of forage quality. Ten individual plants of Bituminaria bituminosa ‘Ecotypes 1’, B. bituminosa ‘Ecotypes 2’, Medicago citrina, and M. arborea from Spain; Colutea istria and Onobrychis aurantiaca from Syria; C. istria from Jordan; Chamaecytisus mollis from Morocco; and Coronilla glauca from France were randomly selected from plots established in a non-tropical dryland environment in northwest Syria in 2000. Five individual plants of each species were cut back to 0.5 m above ground in March 2004. Coppice regrowths were pruned in December 2004 and April 2005 to determine forage yield and proportion of forage in the total above ground biomass (PEFB). Forage samples were analyzed for concentrations of crude protein (CP), lignin(sa), acid detergent fibre (ADFom), neutral detergent fibre (aNDFom), in vitro organic matter (OM) digestibility (IVOMD), and in vitro 24 h gas production (IVGP24h). Matured seeds were hand harvested from the remaining five plants of each species to estimate seed yield. Forage (21–250 kg DM/ha) and seed (0–200 kg DM/ha) yields; PEFB (0.22–0.96); and concentrations of CP (85–115 g/kg DM), lignin(sa) (14–42 g/kg DM), ADFom (94–170 g/kg DM), aNDFom (122–217 g/kg DM), IVOMD (456–617 g/kg OM), and IVGP24h (27–42 ml 200 mg/DM) varied (P<0.05) among shrub species. The IVOMD and IVGP24h were positively correlated (r = 0.75, P<0.032), whereas IVOMD and IVGP24h were negatively correlated with ADFom, lignin(sa) and aNDFom. In terms of forage and seed yields and determinants of forage quality, C. istria from Jordan, M. arborea, B. bituminosa ‘Ecotype-2’, C. istria and O. aurantiaca have higher potential than C. mollis, C. glauca and B. Bituminosa ‘Ecotype-1’ for the development of agroforestry technologies in non-tropical dry areas.     

Partial vapor-phase hydrolysis of peptide bonds: A method for mass spectrometric determination of O-glycosylated sites in glycopeptides

In this study we present a method for determination of O-glycosylation sites in glycopeptides, based on partial vapor-phase acid hydrolysis in combination with mass spectrometric analysis. Pentafluoropropionic acid and hydrochloric acid were used for the hydrolysis of glycosylated peptides. The reaction conditions were optimized for efficient polypeptide backbone cleavages with minimal cleavage of glycosidic bonds. The glycosylated residues were identified by mass spectrometric analysis of the hydrolytic cleavage products. Although glycosidic bonds are partially cleaved under acid hydrolysis, the resulting mass spectra allowed unambiguous determination of the glycosylation sites. Examples are shown with mannosyl- and mucin-type glycopeptides. Performing the hydrolysis in vapor eliminates the risk for contamination of the sample with impurities from the reagents, thus allowing analysis of the reaction products without further purification both by matrix-assisted laser desorption/ionization and electrospray ionization mass spectrometry.     

Anthrax outbreak among Grevy's zebra (Equus grevyi) in Samburu, Kenya

An anthrax outbreak occurred in the Wamba area of southern Samburu, Kenya, between December 2005 and March 2006. The outbreak affected equids including the endangered Grevy's zebras (Equus grevyi), plain zebras (Equis Burchelli) and donkeys (Equus asinus). Most of the deaths were localized in Nkaroni area just west of Wamba town. The diagnosis of anthrax was rapidly confirmed by bacteriological methods. The relevant government departments, including the Kenya Wildlife Service and Veterinary Department, and other stakeholders were promptly informed. Fifty‐three Grevy's zebra and 26 plains zebras died from anthrax. An equal number (eighteen) of adult male and female Grevy's zebras succumbed to the disease. The outbreak affected immature and mature individuals equally. The dead plain zebras included fifteen adult females, two adult males and nine immature individuals. The Veterinary Department responded by vaccinating livestock while Kenya Wildlife Service vaccinated 620 Grevy's zebras within southern Samburu. Examination of sites at which carcasses of animals which succumbed to the disease were burnt, revealed that unsupervised burning did not eliminate anthrax spores in 42% of the cases (n = 14). There is an urgent need to incorporate strategic wildlife disease monitoring in the struggle to save Grevy's zebras and other endangered species.     

Parkin Overexpression Ameliorates PrP106–126-Induced Neurotoxicity via Enhanced Autophagy in N2a Cells

Transmissible spongiform encephalopathies (TSEs) are caused by the accumulation of the abnormal prion protein scrapie (PrP^Sc). Prion protein aggregation, misfolding, and cytotoxicity in the brain are the major causes of neuronal dysfunction and ultimate neurodegeneration in all TSEs. Parkin, an E3 ubiquitin ligase, has been studied extensively in all major protein misfolding aggregating diseases, especially Parkinson’s disease and Alzheimer’s disease, but the role of parkin in TSEs remains unknown. Here we investigated the role of parkin in a prion disease cell model in which neuroblastoma2a (N2a) cells were treated with prion peptide PrP106–126. We observed a gradual decrease in the soluble parkin level upon treatment with PrP106–126 in a time-dependent manner. Furthermore, endogenous parkin colocalized with FITC-tagged prion fragment106–126. Overexpression of parkin in N2a cells via transfection repressed apoptosis by enhancing autophagy. Parkin-overexpressing cells also showed reductions in apoptotic BAX translocation to the mitochondria and cytochrome c release to the cytosol, which ultimately inhibited activation of proapoptotic caspases. Taken together, our findings reveal a parkin-mediated cytoprotective mechanism against PrP106–126 toxicity, which is a novel potential therapeutic target for treating prion diseases.     

Does Gγ/Aγ ratio and Hb F level influence the severity of sickle cell anaemia

Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated -and -thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G/A ratio and Hb F level and correlated these values with the severity of SCA. The results showed that Hb F level varies significantly in both groups of patients with no evident correlation with the mild clinical manifestations. However, G/A ratio correlated significantly with the disease severity where a high ratio was observed in patients with the mild and a low ratio in patients with the severe disease. The results are evaluated and discussed in the light of correlation studies and regression analysis.