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The occurrence of a second osteocalcin (OC2) has been reported in teleost fish, where it coexists with OC1 in some species. While it has been proposed that OC2 gene originated from OC1 through the fish whole-genome duplication event, little information is available on its molecular function and physiological role. The present study brings biological data supporting the presence of OC2 in the mineral phase of teleost fish bone and its association with the mineral phase together with OC1. The occurrence of OC2 forms with different levels of phosphorylation or γ-carboxylation, and with amino acid substitutions was observed. Comparative analysis of mature peptide sequences revealed the high conservation existing between OC1 and OC2, in particular within the core γ-carboxyglutamic acid domain, and suggests that both protein forms may have the same function, i.e., binding of calcium ions or hydroxyapatite crystals.

Background: Expansion of aquaculture requires alternative feeds and breeding strategies to reduce dependency on fish oil (FO) and better utilization of dietary vegetable oil (VO). Despite the central role of intestine in maintaining body homeostasis and health, its molecular response to replacement of dietary FO by VO has been little investigated. This study employed transcriptomic and proteomic analyses to study effects of dietary VO in two family groups of Atlantic salmon selected for flesh lipid content, 'Lean' or 'Fat'., Results: Metabolism, particularly of lipid and energy, was the functional category most affected by diet. Important effects were also measured in ribosomal proteins and signalling. The long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis pathway, assessed by fatty acid composition and gene expression, was influenced by genotype. Intestinal tissue contents of docosahexaenoic acid were equivalent in Lean salmon fed either a FO or VO diet and expression of LC-PUFA biosynthesis genes was up-regulated in VO-fed fish in Fat salmon. Dietary VO increased lipogenesis in Lean fish, assessed by expression of FAS, while no effect was observed on β-oxidation although transcripts of the mitochondrial respiratory chain were down-regulated, suggesting less active energetic metabolism in fish fed VO. In contrast, dietary VO up-regulated genes and proteins involved in detoxification, antioxidant defence and apoptosis, which could be associated with higher levels of polycyclic aromatic hydrocarbons in this diet. Regarding genotype, the following pathways were identified as being differentially affected: proteasomal proteolysis, response to oxidative and cellular stress (xenobiotic and oxidant metabolism and heat shock proteins), apoptosis and structural proteins particularly associated with tissue contractile properties. Genotype effects were accentuated by dietary VO., Conclusions: Intestinal metabolism was affected by diet and genotype. Lean fish may have higher responsiveness to low dietary n-3 LC-PUFA, up-regulating the biosynthetic pathway when fed dietary VO. As global aquaculture searches for alternative oils for feeds, this study alerts to the potential of VO introducing contaminants and demonstrates the detoxifying role of intestine. Finally, data indicate genotype-specific responses in the intestinal transcriptome and proteome to dietary VO, including possibly structural properties of the intestinal layer and defence against cellular stress, with Lean fish being more susceptible to diet-induced oxidative stress.

One of the main constrains for commercial aquaculture production of white seabream (Diplodus sargus) is the high incidence of skeletal malformations in reared fish. The purpose of this study was to obtain a better understanding of the mechanisms involved in the development of these types of skeletal malformations by comparative proteomic analysis of the vertebral column of normal and deformed fish using 2DE for protein separation and MS for protein identification. We observed a 3.2 and 3.4-fold increase in the expression of two tropomyosin isoforms, one of which (tropomyosin-4) is essential for the motility and polarization cycles of osteoclasts. Furthermore, a 1.6, 1.7 and 1.8-fold increase in three parvalbumin spots was detected, suggesting a cellular response to increased intracellular Ca²(+) levels. These results can be interpreted as signs of increased cellular activity in the bone of white seabream with skeletal deformities coupled to a higher degree of calcium mobilization, which elicits further studies into the use of these proteins as indicators of skeletal metabolic state., (Copyright © 2010 Elsevier Inc. All rights reserved.)

A study of the chronological series of mortality due to meningococcal disease in children under one year old, the group of highest incidence during the last epidemy in Cuba, was carried out. Data were collected by doing a survey in an uniform way since 1983 throughout the country. More than 90% of the population between 3 months and 5 years old were vaccinated with VAMENGOC BC since the end of 1988 until April, 1990. The behaviour of this disease was studied in order to identify the influence of this vaccine. It is stressed that the mortality incidence reached its epidemic achme in 1986 and begins a slow descence which is accentuated in 1990 and 1991, with an annual relative decrease of 26.1 and 34.9%, respectively. The highest mortality rate was found in 1984, with a significant reduction in 1990 (-23.8%) and 1991 (-41.8%), after the culmination of the vaccination campaign with VA-MENGOC BC. It was detected that morbimortality, which is lower in children under one month because of the probable protection provided by maternal antibodies, started to increase until the fifth month of life, when it is observed a trend towards the reduction of morbidity and mortality. According to the present immunization chronogram, overall protection in only attained after the sixth mont of life.

Children less than one year old behave as the group with the highest incidence of meningococcal disease during all the epidemic period in the past '80s decade in Cuba. There were used chronological series of monthly incidence rates between 1983 and 1990, in order to identify the behavior of seasonality, taking into account the clinical form and the insert of years 1989 and 1990 in the series: in both of them a massive antimeningococcal vaccination campaign took place. It is evident that seasonality has a different behavior in accordance with the clinical form: it is like the countries from the northern hemisphere with a moderate climate for the meningoencephalitis, and like the countries of the southern hemisphere with a warm climate for the meningococcal syndrome. Months of the rainy period have the lowest seasonal index. Modifications of these seasonal patterns are not found after executing the vaccination.

The assessment of the after-licensing efficacy of the Cuban vaccine VA-MENGOC-BC was performed one year after the mass immunization campaign was completed in children under 6 years of age in the Province of Holguín which had the second highest incidence rate of meningococcal disease during 1988 in Cuba. In the design of the study the following aspects were taking into account: case definition; case detection, determination of the state of vaccination, and comparability of exposure. The utilization of 2 case definitions with different sensitivity and specificity is introduced within the methodology, as well as 2 estimation methods. Incidence rates from exposed and nonexposed subjects, as well as the ratio of cases and of the vaccinated population are used. The impact of this prophylactic intervention was determined by the estimation of the percentual preventive population fraction. Among outstanding results, the high efficacy of more than 98% found in both variants of case definition is to be mentioned. It is evidenced that the effect of the vaccine accounts for more than 80% of the observed case reduction. Such reduction in the number of cases was obtained without changing diagnostic criteria since the isolation of the agents was hept at levels similar to the ones from previous years.

The effectiveness or post-license efficacy of the BC antimeningococcal vaccine (VA-MENGOC-BC) was assessed 1 year after the end of the immunization campaign in children aged 0 to 5 years. Occurrence of the disease before and after intervention is described and effectiveness is estimated following the recommendations described by Orenstein et al. We used 2 case definitions to compare results in groups formed following different criteria, according to the employed diagnostic tests. Two formulas are used to assess efficacy: one, estimating the rates among vaccinated and non-vaccinated; and the other one, estimating the ratio of cases per vaccinated population. The increase of the relative annual decrease of the incidence occurring since 1985--a decrease of 10% or less--which in 1990 reached 34.6% should be stressed; the ratio of new cases prevented by the intervention was higher than 75%. Effectiveness or post-license efficacy was close to 90%, independently from the case definition variant or formula employed.