In vitro modulation of reactive oxygen and nitrogen intermediate (ROI/RNI) production in Crassostrea gigas hemocytes

Bivalve hemocyte competence has been measured by quantifying functional characteristics, including reactive oxygen intermediate (ROI) production after activation with zymosan or phorbol myristate acetate (PMA). However, untreated oyster hemocytes also produce ROI and RNI (reactive nitrogen intermediates) after bleeding even if not stimulated by zymosan or PMA. Extensive investigation of this parameter by flow cytometry showed that, in vitro, ROI/RNI production by untreated hemocytes maintained in seawater appeared to be independent of both bacterial burden in the serum and non-self particle phagocytosis. ROI/RNI production in granulocytes was higher than in hyalinocytes and could be intensified when activated by zymosan but not by PMA. Both cell types used NADPH-oxidase- and NO-synthase-like pathways to produce these molecules; the NO-synthase pathway seemed relatively more dominant in hyalinocytes and NADPH-oxidase appeared more effective in granulocytes. These results provide new insights for interpreting the modulation of ROI/RNI production by untreated hemocytes shown by other studies, relative to environmental conditions or physiological status of the oysters.     

Soluble sugars and carboxylic acids in ripe apricot fruit as parameters for distinguishing different cultivars

Major sugar and carboxylic acid components in apricot flesh fruits were detected and quantified. Fifty-one genotypes including clones growing in France, Spain, Italy, Greece and USA, belonging to the INRA germ plasm collection has been evaluated. Principal component analysis (PCA) has been performed to study correlation among fruit quality measurements and to interpret relationships between genotypes as a tool for germ plasm characterization. A marked variation in malic and citric acid content has been observed and PCA revealed clusters of apricot genotypes for the malic/citric ratio content. A good correlation between sugar component and refractometer index (r = 0.83) has been detected. The wide range of diversity in malic and citric acid content in apricot germ plasm makes it possible to breed and select genotypes with improved flavour on the basis of superior phenotypes. This revised version was published online in July 2006 with corrections to the Cover Date.     

Conservation management for Orthoptera in the Dadia reserve, Greece

The diversity patterns, the ecological structure and the typical species of the orthopteran assemblage in the Dadia reserve are investigated. The reserve was designed to protect the black vulture (Aegypius monachus) and other raptors. A total of 39 orthopteran species were found, including Paranocarodes chopardi, a pamphagid species with very restricted distribution. All species can be represented in a network of six complementary habitats, including open oak woodlands, agricultural fields separated with hedges, humid grasslands, as well as serpentine grasslands. The buffer zone of the reserve is far more important for Orthoptera conservation than the core areas, which host most of the black vulture nests. Management focusing on raptors is in general compatible with conservation of Orthoptera. We suggest the maintenance of forest openings in the buffer zone, the maintenance of forest heterogeneity, the enhancement of periodical livestock grazing, and the use of nine indicator species and Paranocarodes chopardi in the reserve monitoring program.     

Exposure Patterns and Long Term Sequelae on Adults and Children in Two Canadian Indigenous Communities Exposed to Methylmercury

Health Canada has been collecting data on Inuit and First Nations' methylmercury (MeHg) levels for 25 years. A national overview has been completed and more focussed analyses have now been initiated. This paper deals with two interdependent analytical components: 1) a longitudinal overview of the two most extensively sampled communities in Canada: Grassy Narrows and Whitedog, the residents of which were exposed to ‘point source’ mercury pollution in the 1970's; 2) fetal and post-natal exposure to mercury in these two communities including an outline of the First Nation MeHg child development pilot project in the two communities. A retrospective analysis of Grassy Narrows and Whitedog shows a decreasing MeHg trend in both communities. In Grassy Narrows the average individual annual peak methylmercury level in blood has decreased significantly, from 23.80 ppb (range 1.50–322.90) in 1976 to 7.5 ppb (1.7–46.7) in 1995 (r=-0.65, p<0.001). In Whitedog the average peak has also decreased significantly, from 12.87 ppb (1.50–172.00) in 1976 to 6.1 ppb (1.7–33.3) in 1995 (r=-0.59, p<0.005). However, behind these positive trends is the reality of two communities still suffering the effects of disrupted lifestyles and socio-cultural damage. A number of cord blood samples, maternal blood samples, and samples from women of child-bearing age from these communities have been in the “risk” group (according to the 1990 WHO guidelines). We are therefore now assessing the long term effects of fetal exposure in the communities. Standard clinical examinations in the past failed to prove abnormalities attributable to methylmercury but did not include subtle neuropsychological development tests. Many of the fetally exposed children are now in secondary school. Therefore, we have initiated a pilot project to assess long term effects of methylmercury exposure on the neuropsychological development of these children whose fetal exposure we know. The pilot child development project which was initiated in 1995 in Grassy Narrows and Whitedog, with community support, includes four main components: i) a school records review, looking at attendance, marks, and atypical behaviour; ii) teachers' questionnaires, targeting child behaviour; iii) an in-depth neuropsychological test battery focussing on subtle factors, such as memory, attention, executive functions, perceptual functions and sensory / motor development; and iv) hair sampling, providing current MeHg levels to correlate with results from the previous sampling and findings from the first three components. An overview of progress is given.     

Antibody response to an autogenous vaccine and serologic profile for Streptococcus suis capsular type 1/2

An autogenous vaccine was developed, using sonicated bacteria, with a strain of Streptococcus suis capsular type 1/2. The objectives of this study were to evaluate the antibody response following vaccination and to assess the changes in antibody levels in pigs from a herd showing clinical signs of S. suis capsular type 1/2 infection in 6- to 8-week-old pigs. An enzyme-linked immunosorbent assay using the vaccine antigen was standardized. Results from a preliminary study involving 2 control and 4 vaccinated 4-week-old pigs indicated that all vaccinated pigs produced antibodies against 2 proteins of 34 and 43 kDa, respectively, and, in 3 out of 4 vaccinated pigs, against the 117-kDa muramidase-released protein. For the serologic profile, groups of 30 pigs from the infected herd were blood sampled at 2, 4, 6, 8, and 10 weeks of age. The lowest antibody level was observed between weeks 6 and 8, presumably corresponding to a decrease in maternal immunity. A marked increase was seen at 10 weeks of age, shortly after the onset of clinical signs in the herd. For the vaccination field trial, newly weaned, one-week-old piglets were divided into 2 groups of 200 piglets each (control and vaccinated); blood samples were collected from 36 piglets in each group at 2-week intervals for 12 weeks. A significant increase (P 0.05) in antibody response was observed 4 weeks following vaccination and the level of antibodies stayed high until the end of the experiment. In the control group, the increase was only observed at 13 weeks of age, probably in response to a natural infection. The response to the vaccine varied considerably among pigs and was attributed, in part, to the levels of maternal antibodies at the time of vaccination. No outbreak of S. suis was observed in the control or vaccinated groups, so the protection conferred by the vaccine could not be evaluated.     

Genetic survey of 10 Indian coconut landraces by simple sequence repeats (SSRs)

A rich genetic diversity of coconut exists in farmer's fields, which represent valuable genetic resource for breeding. The study was conducted to assess the pattern of diversity in 102 coconut palms representing 10 landraces from 3 coconut-growing communities of India using 14 simple sequence repeat (SSR) markers. A total of 90 alleles were detected with an average of 6.42 alleles per locus and an average polymorphism information content of 0.61. Expected heterozygosity (H_e) was highest for the two tall landraces from Pallikkara community, while the least heterozygosity was observed for the dwarf coconut landraces from Vayalar community. Mean fixation index (F_ST) of 0.42 indicates a high level of population differentiation. A low gene flow (N_m) of 0.37 was observed. Based on molecular data, genetic similarities were calculated. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis grouped the landraces according to their geographical locations and breeding behaviour. The practical implications of this study in farmer participatory evaluation and conservation of coconut genetic resources are highlighted.     

Pomological and Nutraceutical Properties in Apricot Fruit: Cultivation Systems and Cold Storage Fruit Management

We have investigated the effect of cultivation systems and fruit post-harvest management on the antioxidant properties of apricot fruits. Trees of five cultivars ‘Tyrinthos’, ‘Cafona’, ‘Bella d’Italia’, ‘Vitillo’ and ‘Pellecchiella’ were cultivated under integrated and organic systems. Fruits were collected at full maturity stage and analyzed either immediately or after storage at 4±0.5 °C and 85% of relative humidity for seven and 14 days. The main pomological traits (weight, colour, flesh firmness, total soluble sugars, titratable acidity) and antioxidant properties were analyzed. The total antioxidant capacity (TAC by TEAC method), total phenols content (TP by Folin-Ciocalteu method) and carotenoid content by HPLC-DAD were monitored. Cultivar characterization by principal component analysis (PCA) indicated a large variability on pomological and antioxidant properties of apricot fruits. ‘Bella d’Italia’ showed better TAC and TP values compared to the other cultivars. ANOVA interactions between cultivar and cultivation system (organic/integrated) were found for the antioxidant properties. These interactions may help to select a set of genotypes with better performances under organic system, which in our study might be indicated in ‘Cafona’ and ‘Bella d’Italia’.     

The Panama Tall and the Maypan hybrid coconut in Jamaica: did genetic contamination cause a loss of resistance to Lethal Yellowing?

We applied Bayesian population assignment methods to assess the trueness to type of four populations of the coconut cultivar Panama Tall (PNT) located in Jamaica and found that two of them presented a high percentage of off-types, while genetic contamination was low in the two others. The PNT is the pollen parent of the MAYPAN hybrid, which used to be planted in Jamaica to control an epidemic disease: Lethal Yellowing. The main source of contamination was the susceptible Jamaica Tall, thus increasing the susceptibility in the resulting MAYPAN progeny. The incidence of genetic contamination seems however to be insufficient to be the only cause of the latest outbreak of the disease. Neither the MAYPAN nor its parents can be said resistant in the present context of Jamaica.