Synthesis and biological activity of naphtho[1,2,6,5]pyrano[3,4-f]phthalazine- 4, 14-diones

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Neutralizing activities of caprine antibodies towards conserved regions of the HCV envelope glycoprotein E2

Anti HCV vaccine is not currently available and the present antiviral therapies fail to cure approximately half of the treated HCV patients. This study was designed to assess the immunogenic properties of genetically conserved peptides derived from the C-terminal region of HVR-1 and test their neutralizing activities in a step towards developing therapeutic and/or prophylactic immunogens against HCV infection. Antibodies were generated by vaccination of goats with synthetic peptides derived from HCV E2. Viral neutralizing capacity of the generated anti E2 antibodies was tested using in vitro assays. Goats immunized with E2 synthetic peptides termed p412 [a.a 412-419], p430 [a.a 430-447] and p517 [a.a 517-531] generated high titers of antibody responses 2 to 4.5 fold higher than comparable titers of antibodies to the same epitopes in chronic HCV patients. In post infection experiments of native HCV into cultured Huh7.5 cells anti p412 and anti p 517 were proven to be neutralizing to HCV genotype 4a from patients' sera (87.5% and 75% respectively). On the contrary anti p430 exhibited weak viral neutralization capacity on the same samples (31.25%). Furthermore Ab mixes containing anti p430 exhibited reduced viral neutralization properties. From these experiments one could predict that neutralization by Abs towards different E2-epitopes varies considerably and success in the enrichment of neutralization epitope-specific antibodies may be accompanied by favorable results in combating HCV infection. Also, E2 conserved peptides p517 and p412 represent potential components of a candidate peptide vaccine against HCV infection

Conserved peptides within the E2 region of Hepatitis C virus induce humoral and cellular responses in goats

The reason(s) why human antibodies raised against hepatitis C virus (HCV) E2 epitopes do not offer protection against multiple viral infections may be related to either genetic variations among viral strains particularly within the hypervariable region-1 (HVR-1), low titers of anti E2 antibodies or interference of non neutralizing antibodies with the function of neutralizing antibodies. This study was designed to assess the immunogenic properties of genetically conserved peptides derived from the C-terminal region of HVR-1 as potential therapeutic and/or prophylactic vaccines against HCV infection. Goats immunized with E2-conserved synthetic peptides termed p36 (a.a 430–446), p37(a.a 517–531) and p38 (a.a 412–419) generated high titers of anti-p36, anti-p37 and anti-P38 antibody responses of which only anti- p37 and anti- p38 were neutralizing to HCV particles in sera from patients infected predominantly with genotype 4a. On the other hand anti-p36 exhibited weak viral neutralization capacity on the same samples. Animals super-immunized with single epitopes generated 2 to 4.5 fold higher titers than similar antibodies produced in chronic HCV patients. Also the studied peptides elicited approximately 3 fold increase in cell proliferation of specific antibody-secreting peripheral blood mononuclear cells (PBMC) from immunized goats. These results indicate that, besides E1 derived peptide p35 (a.a 315–323) described previously by this laboratory, E2 conserved peptides p37 and p38 represent essential components of a candidate peptide vaccine against HCV infection

Level of information about dietary fibre: a study involving 10 Countries

Introduction: Dietary fibre (DF) is recognized as healthy for long, so that health claims are allowed by the European Food Safety Authority (EFSA) due to its proved benefits, extended but not only confined to many diseases of the gastrointestinal tract. Objective: This work intended to analyse the level of information about DF in 10 countries, situated in Europe, Africa and South America. Methods: A descriptive cross-sectional study was undertaken through a survey based on a questionnaire of self-response applied to a sample of 6010 participants. The data were lately treated by factor and cluster analyses, including validation methodologies. Results: Factor analysis showed that ten of the twelve items used to assess the knowledge about DF could be arranged into two factors: one related to health effects (α =0.854) and the other to the sources (α =0.644). Furthermore, cluster analysis showed that the participants could be divided into three groups: 1) Good knowledge about sources and health effects of DF; 2) Good knowledge about the sources of DF but poor knowledge about the health effects; 3) Poor knowledge about the sources and health effects of DF. Conclusions: The results clearly allowed identifying two factors and three clusters, and the variables that most influenced cluster membership were country, living environment and level of education.info:eu-repo/semantics/publishedVersio

Different experimental approaches in modelling cataractogenesis: An overview of selenite-induced nuclear cataract in rats

Cataract, the opacification of eye lens, is the leading cause of blindness worldwide. At present, the only remedy is surgical removal of the cataractous lens and substitution with a lens made of synthetic polymers. However, besides significant costs of operation and possible complications, an artificial lens just does not have the overall optical qualities of a normal one. Hence it remains a significant public health problem, and biochemical solutions or pharmacological interventions that will maintain the transparency of the lens are highly required. Naturally, there is a persistent demand for suitable biological models. The ocular lens would appear to be an ideal organ for maintaining culture conditions because of lacking blood vessels and nerves. The lens in vivo obtains its nutrients and eliminates waste products via diffusion with the surrounding fluids. Lens opacification observed in vivo can be mimicked in vitro by addition of the cataractogenic agent sodium selenite (Na2SeO3) to the culture medium. Moreover, since an overdose of sodium selenite induces also cataract in young rats, it became an extremely rapid and convenient model of nuclear cataract in vivo. The main focus of this review will be on selenium (Se) and its salt sodium selenite, their toxicological characteristics and safety data in relevance of modelling cataractogenesis, either under in vivo or in vitro conditions. The studies revealing the mechanisms of lens opacification induced by selenite are highlighted, the representatives from screening for potential anti-cataract agents are listed

Physiological & behavioural responses of Ruditapes decussatus WHO

ABSTRACT The clam Ruditapes decussatus was used as a bioindicator for pollution to determine the toxicity of a herbicide (48% glyphosate, 'roundup') and an insecticide (50% chlorpyrifosmethyl, 'reldan'). After estimating LC 50 (µl L -1 ) and LT 50 (days) of both organophosphrous pesticides over 60 days, the impact of ½ LC 50 of roundup (1.1µl L -1 ) and reldan (0.6 µl L -1 ) was measured. After two months of treatment, reldan reduced valve activity more than roundup; the rest period increased with increasing time of exposure. There was direct relationship between valve movement and metabolic heat output of respiration and excretion. The decrease in respiration rate was associated with a decrease in ammonia excretion. Thus valve-movement responses of R. decussatus to ½ LC 50 of the two pesticides are type-dependent. Both pesticides reduced physiological condition, but reldan is more potent than roundup and its effect is time-dependent. Respiration and excretion rates were components of the energy expenditure that accounted for the decline in metabolism and excretion with increasing the time of exposure to pesticides. This study highlights the potential use of behavioural and physiological response of a sentinel organism for monitoring the pesticides in the marine environment

Physiological and behavioural responses of Ruditapes decussatus to roundup and reldan

The clam Ruditapes decussatus was used as a bioindicator for pollution to determine the toxicity of a herbicide (48% glyphosate, ‘roundup') and an insecticide (50% chlorpyrifosmethyl, ‘reldan'). After estimating LC50 (µl L-1) and LT50 (days) of both organophosphrous pesticides over 60 days, the impact of ½ LC50 of roundup (1.1µl L-1) and reldan (0.6 µl L-1) was measured. After two months of treatment, reldan reduced valve activity more than roundup; the rest period increased with increasing time of exposure. There was direct relationship between valve movement and metabolic heat output of respiration and excretion. The decrease in respiration rate was associated with a decrease in ammonia excretion. Thus valve-movement responses of R. decussatus to ½ LC50 of the two pesticides are type-dependent. Both pesticides reduced physiological condition, but reldan is more potent than roundup and its effect is time-dependent. Respiration and excretion rates were components of the energy expenditure that accounted for the decline in metabolism and excretion with increasing the time of exposure to pesticides. This study highlights the potential use of behavioural and physiological response of a sentinel organism for monitoring the pesticides in the marine environment. KEY WORDS: LC50, glyphosate, chlorpyrifos-methyl, valve movement, oxygen consumption, ammonia excretion, energy lost. Egyptian Journal of Botany Vol.5 2003: 108-11