Effects of post-teneral nutrition and ginger root oil exposure on longevity and mortality in bait treatments of sterile male Ceratitis capitata

Area-wide Sterile Insect Technique (SIT) programmes against medfly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), are being increasingly implemented worldwide. A key issue for SIT is to release sterile males that are sufficiently competitive with males from the wild population. Post-teneral nutrition and ginger root oil (GRO) exposure of sterile males prior to release have been shown to improve male competitiveness or performance. However, few studies are available on the effect of post-teneral nutrition and ginger oil exposure on longevity and mortality in bait treatments by sterile male C. capitata . In this study, we found that longevity was increased by the addition of protein to the standard pre-release sugar diet, whereas exposure to GRO did not influence the longevity of sterile males. Mortality in spinosad baits was influenced both by diet and GRO exposure. Sterile males on a protein-deprived diet suffered greater mortality than sterile males fed with both sugar and protein. When sterile males were fed on the protein-deprived diet, GRO exposure increased their mortality. However, no significant differences were found in adults on the sugar-protein diet, whether or not they had been exposed to GRO. These results show, for the first time, a negative effect of GRO exposure in terms of increasing mortality in proteinaceous bait treatments, a common practice in areas where SIT is implemented. Nevertheless, this effect could be reduced by the addition of protein to the standard pre-release diet. The implications of these results for SIT programmes against C. capitata are discussed.     

Branchpoint for heme alkylation and metabolite formation in the oxidation of arylacetylenes by cytochrome P-450

Phenylacetylene and biphenylacetylene are oxidized by cytochrome P-450 to the corresponding arylacetic acids. The acetylenic hydrogen shifts to the adjacent carbon and one atom of molecular oxygen is incorporated into the carboxylic acid group in these transformations, which are subject to a large kinetic isotope effect when the acetylenic hydrogen is replaced by deuterium. The same products and isotope effects are observed when the two arylacetylenes are oxidized by m-chloroperbenzoic acid rather than by the enzyme. In contrast, the inactivation of cytochrome P-450 that occurs during the oxidation of phenylacetylene is insensitive to deuterium substitution. The partition ratio between metabolite formation and enzyme inactivation consequently changes from 26 to 15 in going from phenylacetylene to the deuterated analogue. Metabolite formation therefore diverges from heme alkylation very early in the catalytic process.     

Study of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae at five sites in western Spain

A comparative study is presented of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae, collected during 1995 with Hirst samplers (Burkard or Lanzoni) at five sites in western Spain: two Mediterranean sites located in the south (Huelva and Seville) and three Atlantic sites in the north (Orense, Vigo and Santiago). The annual pollen of Poaceae and Plantaginaceae collected in the Atlantic cities was found to be twice that in the Mediterranean sites, and the total amount of Urticaceae was higher at sites with an urban environment and subject to sea influence (Vigo, Huelva and Seville). At all the sites, the start of the main pollination periods (MPP) took place in the following order: Urticaceae, Plantaginaceae and Poaceae. It was also observed that the MPP of these three pollen types began earlier in Huelva and Seville, where the mean temperatures necessary for the beginning of pollen emissions are recorded very early. Regarding the variation in pollen concentrations throughout the year, Urticaceae presented peaks of maximum concentration in March (Huelva, Seville, Vigo and Orense) and June (Santiago); Plantaginaceae in March (south) and June (north); and Poaceae in May (south) and June–July (north). At northern sites, pollen emissions of Urticaceae and Plantaginaceae continued throughout the summer, while in the south they decreased considerably from May onwards. From the allergenic point of view, the indices of reactivity described for Urticaceae and Poaceae were exceeded more often at northern sites, in particular at Vigo. The meteorological conditions associated with periods of highest pollen emission of these three herbaceous types are a rise in mean temperature, light or absent rainfall, and abundant sunshine. The statistical correlations between pollen emissions and meteorological factors were not well-defined, either for the stations or for all the taxa, although they were clearer for the Atlantic cities and for Urticaceae.     

Envy and egalitarianism in Aboriginal Australia: An integrative approach

The word ‘envy’ directs attention to feelings and cognitions that are especially important sources of information in our complicated sociality. As it is delimited by philosophers, economists, psychologists and others, envy is conceptually nested within a family that includes evil eye beliefs, inequity aversion, strong reciprocity and social comparison. Although the accumulation of work in these areas is substantial, anthropological treatments of envy are rare. Given repeated assertions of envy's universality and its potential importance for understanding widespread aspects of the human condition, a comparative eye seems essential. I present an account of ‘jealous’ in Aboriginal Australia via a framework that casts emotions as emerging from the interaction of psychobiological and sociocultural processes. According to this perspective, ‘envy’ should not be regarded as an invariant human condition but rather as a Western version of what, in a more generic human form, may both defend the individual and the larger sociality.     

Protein control of prosthetic heme reactivity. Reaction of substrates with the heme edge of horseradish peroxidase

Incubation of horseradish peroxidase with phenylhydrazine and H2O2 markedly depresses the catalytic activity and the intensity, but not position, of the Soret band. Approximately 11-13 mol of phenylhydrazine and 25 mol of H2O2 are required per mol of enzyme to minimize the chromophore intensity. The enzyme retains some activity after such treatment, but this activity is eliminated if the enzyme is isolated and reincubated with phenylhydrazine. The prosthetic heme of the enzyme does not react with phenylhydrazine to give a sigma-bonded phenyl-iron complex, as it does in other hemoproteins, but is converted instead to the delta-mesophenyl and 8-hydroxymethyl derivatives. The loss of activity is due more to protein than heme modification, however. The inactivated enzyme reacts with H2O2 to give a spectroscopically detectable Compound I. The results imply that substrates interact with the heme edge rather than with the activated oxygen of Compounds I and II and specifically identify the region around the delta-meso-carbon and 8-methyl group as the exposed sector of the heme. Horseradish peroxidase, in contrast to cytochrome P-450, generally does not catalyze oxygen-transfer reactions. The present results indicate that oxygen-transfer reactions do not occur because the activated oxygen and the substrate are physically separated by a protein-imposed barrier in horseradish peroxidase.     

Monofunctional platinum(II) compounds and nucleolar stress: is phenanthriplatin unique?

JBIC Journal of Biological Inorganic Chemistry - Platinum anticancer therapeutics are widely used in a variety of chemotherapy regimens. Recent work has revealed that the cytotoxicity of...     

Iron chelator deferiprone rescues memory deficits,hippocampal BDNF levels and antioxidant defenses in an experimental model of memory impairment

Brain-derived neurotrophic factor (BDNF) plays a key role in neural development and physiology, as well as in pathological states. Post-mortem studies demonstrate that BDNF is reduced in the brains of patients affected by neurodegenerative diseases. Iron accumulation has also been associated to the pathogenesis of neurodegenerative diseases. In rats, iron overload induces persistent memory deficits, increases oxidative stress and apoptotic markers, and decreases the expression of the synaptic marker, synaptophysin. Deferiprone (DFP) is an oral iron chelator used for the treatment of systemic iron overload disorders, and has recently been tested for Parkinson’s disease. Here, we investigated the effects of iron overload on BDNF levels and on mRNA expression of genes encoding TrkB, p75^NTR, catalase (CAT) and NQO1. We also aimed at investigating the effects of DFP on iron-induced impairments. Rats received iron or vehicle at postnatal days 12–14 and when adults, received chronic DFP or water (vehicle). Recognition memory was tested 19 days after the beginning of chelation therapy. BDNF measurements and expression analyses in the hippocampus were performed 24 h after the last day of DFP treatment. DFP restored memory and increased hippocampal BDNF levels, ameliorating iron-induced effects. Iron overload in the neonatal period reduced, while treatment with DFP was able to rescue, the expression of antioxidant enzymes CAT and NQO1.