Katerina A. Moutou

Mitochondrial DNA variation in Northeast Atlantic and Mediterranean populations of Norway lobster, Nephrops norvegicus

Analysis of the genetic structure of the Norway lobster (Nephrops norvegicus), a marine crustacean with high commercial value, was undertaken to gain information regarding the differentiation of Atlantic from Mediterranean populations of marine invertebrates. Restriction fragment length polymorphism analysis of two mitochondrial DNA segments, 3.6 kilobases in total, was performed. Twelve populations from the North Sea, Irish Sea, Portuguese coast and Aegean Sea were analysed. Low levels of differentiation were found among them (FST = 0.018, P < 0.001) and there were no signs of an Atlantic–Mediterranean divide or of an isolation‐by‐distance scheme of differentiation. Possible reasons for these low levels of differentiation can be found in the recent expansion of N. norvegicus populations. This is supported by the mismatch distribution of pairwise haplotype differences, as well as by the high mean haplotype diversity (h = 0.93) combined with medium nucleotide diversity (π = 0.0057) (in comparison to values for marine crustaceans or teleosts) found in this study. This combination of high levels of haplotype diversity with moderate to low levels of nucleotide diversity has also been frequently attributed to a recent time of divergence for various marine species. No evidence was found for a Mediterranean refugium during glaciation periods, separate from the Atlantic, as has been reported for some marine species. The Irish Sea population was the most differentiated as a result of reduced levels of diversity. Results are also discussed in the light of future management of N. norvegicus stocks.

Major histocompatibility complex variation at class II DQA locus in the brown hare (Lepus europaeus)

The major histocompatability complex (MHC) is a multigene family of receptors that bind and present antigenic peptides to T‐cells. Genes of the MHC are characterized by an outstanding genetic polymorphism, which is considered to be maintained by positive selection. Sites involved in peptide binding form binding pockets (P) that are collectively termed the peptide‐binding region (PBR). In this study, we examined the level of MHC genetic diversity within and among natural populations of brown hare (Lepus europaeus) from Europe and Anatolia choosing for analysis of the second exon of the DQA locus, one of the most polymorphic class II loci. We aimed at an integrated population genetic analysis of L. europeaus by (i) correlating MHC polymorphism to genetic variability and phylogenetic status estimated previously from maternally (mtDNA) and biparentally (allozymes, microsatellites) inherited loci; and (ii) comparing full‐length exon amino acid polymorphism with functional polymorphism in the PBR and the binding pockets P1, P6 and P9. A substantial level of DQA exon 2 polymorphism was detected with two completely different set of alleles between the Anatolian and European populations. However, the phylogeny of full‐length exon 2 Leeu‐DQA alleles did not show a strong phylogeographic signal. The presence of balancing selection was supported by a statistically significant excess of nonsynonymous substitutions over synonymous in the PBR and a trans‐species pattern of evolution detected after phylogenetic reconstruction. The differentiating patterns detected between genetic and functional polymorphism, i.e. the number and the distribution of pocket variants within and among populations, indicated a hierarchical action of selection pressures.

Development of the Risk Assessment Suicidality Scale (RASS): A population-based study

BACKGROUND Suicide and suicide attempts are significant and costly public health problems. In order to prevent suicidal and other self-injurious behaviors, research on the multiple factors involved in these behaviors with comprehensive and user-friendly instruments is necessary. The aim of the current study was to construct a self-report instrument with emphasis on items describing suicide-related behavior itself rather than strongly related clinical features on the basis of a general population study. METHODS Twelve items comprising a new scale were applied to 734 subjects from the general population (40.6% males and 59.4% females) aged 40.8±11.5 along with the STAI and the CES-D. RESULTS The scoring method was developed on the basis of frequency table of responses to the individual scale items. The factor analysis returned 3 factors explaining 59.19% of total variance (Intention, Life, and History). The Cronbachs alpha was 0.85 for the Intention, 0.69 for the Life and 0.52 for the History subscale. LIMITATION The findings need replication in clinical and epidemiologic studies. CONCLUSION The RASS is a reliable and valid instrument which might prove valuable in the assessment of suicidal risk in the general population as well as in mental patients.

Obesity and smoking in patients with schizophrenia and normal controls: a case-control study.

Cardiovascular risk factors, especially obesity and smoking are highly prevalent in patients with schizophrenia. Central obesity and the metabolic syndrome are conditions mostly attributed to the use of antipsychotic medication and lifestyle habits, and they constitute a significant health concern. Our study sample included 105 patients suffering from schizophrenia aged 36.25+/-10.03 and 156 normal control subjects aged 36.03+/-11.33. All patients were in- or out-patients of a private hospital. Clinical diagnosis was made according to DSM-IV-TR criteria. Height, weight, waist circumference and number of cigarettes smoked daily were recorded. Duration of illness was calculated based on records concerning the age of first onset of psychotic symptoms. Body Surface Area (BSA) and Body Mass Index (BMI) were calculated as well as % body fat, with the use of LifeWise Body Fat Analyzers No 63-1525. The results of analysis of variance suggested a significant main effect regarding diagnosis and sex as well as for their interaction. There were significant differences between patients and controls regarding body weight, waist circumference, BMI, BSA and % body fat, with patients, especially females, being more obese than controls. The results of the present study corroborate the increased prevalence of obesity in schizophrenia. The interpretation of this finding remains unclear.

RFLP analysis of mitochondrial DNA to evaluate genetic variation in striped red mullet (Mullus surmuletus L.) and red mullet (Mullus barbatus L.) populations.

Abstract: The genetic differentiation of striped red mullet (Mullus surmuletus) and red mullet (Mullus barbatus) was investigated in 6 Mediterranean populations of each species by means of restriction fragment length polymorphism analysis of mitochondrial DNA. Three segments amplified by polymerase chain reaction (control region, COI, and 12S–16S ribosomal RNA) were digested with 20 restriction endonucleases, revealing 71 haplotypes for M. surmuletus and 30 for M. barbatus. For the two species nucleotide diversity was equally distributed within and among populations, leading to NST values of 0.545 and 0.500 for M. surmuletus and M. barbatus, respectively. However, intrapopulation and interpopulation genetic structuring appeared to be much higher for M. surmuletus than for M. barbatus (1.88% vs. 0.46% of mean intrapopulation nucleotide diversity; 1.94% vs. 0.47% of mean interpopulation nucleotide diversity; 0.055% vs. 0.002% of net interpopulation divergence). Furthermore, 81.69% of the haplotypes observed for M. surmuletus were unique, whereas 70.29% of M. barbatus individuals were grouped in 3 common haplotypes. Given that fishing pressure and population sizes are similar for both species, this differentiation could be attributed to differences in biological parameters and life histories between the two species, coupled with oceanographic conditions prevailing in the studied area.

Domestication does not narrow MHC diversity in Sus scrofa

The Major Histocompatibility Complex (MHC) is a multigene family of outstanding polymorphism. MHC molecules bind antigenic peptides in the peptide-binding region (PBR) that consists of five binding pockets (P). In this study, we compared the genetic diversity of domestic pigs to that of the modern representatives of their wild ancestors, the wild boar, in two MHC loci, the oligomorphic DQA and the polymorphic DRB1. MHC nucleotide polymorphism was compared with the actual functional polymorphism in the PBR and the binding pockets P1, P4, P6, P7, and P9. The analysis of approximately 200 wild boars collected throughout Europe and 120 domestic pigs from four breeds (three pureblood, Pietrain, Leicoma, and Landrace, and one mixed Danbred) revealed that wild boars and domestic pigs share the same levels of nucleotide and amino acid polymorphism, allelic richness, and heterozygosity. Domestication did not appear to act as a bottleneck that would narrow MHC diversity. Although the pattern of polymorphism was uniform between the two loci, the magnitude of polymorphism was different. For both loci, most of the polymorphism was located in the PBR region and the presence of positive selection was supported by a statistically significant excess of nonsynonymous substitutions over synonymous substitutions in the PBR. P4 and P6 were the most polymorphic binding pockets. Functional polymorphism, i.e., the number and the distribution of pocket variants within and among populations, was significantly narrower than genetic polymorphism, indicative of a hierarchical action of selection pressures on MHC loci.

Genetic structure of three marine fishes from the Gulf of Pagasitikos (Greece) based on allozymes, RAPD, and mtDNA RFLP markers

In the present work we used three molecular techniques (allozymes, RAPDs and mtDNA RFLPs) in order to study the genetic structure of three commercial marine species (Mullus surmuletus, Mullus barbatus, and Pagellus erythrinus). Each species was sampled from three locations within the Gulf of Pagasitikos, Greece and from two neighbouring locations outside the Gulf (Trikeri and Alonissos). Values of genetic heterozygosity and nucleotide diversity for all populations studied were similar or above the mean values observed in marine fishes. None of the three types of molecular markers used revealed diagnostic patterns, which could allow the allocation of individuals to one of the populations. The analyses revealed that the three populations within Pagasitikos were homogenous representing thus a panmictic stock. However, there were evidences of genetic population subdivision between localities from inside and outside of the Pagasitikos Gulf. The results provide essential information for the design of a sustainable management plan of the Gulf of Pagasitikos and its demersal fish resources.

Standardization of the TEMPS-A in the Greek general population

BACKGROUND The current study evaluates the reliability and factor-structure replicability of the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A) in its Greek Version. METHODS The TEMPS-A was administered to a convenient sample of 734 subjects from the general Greek population (436 females; 59.4% and 298 males; 40.6%). Their mean age was 40.80±11.48 years (range 25-67 years). The analysis included the calculation of Chronbachs alpha, the calculation of the threshold to define dominant temperaments (+2 standard deviations or 95th percentile), confirmatory factor analysis and the calculation of Pearson correlation coefficients between the temperament scales scores. Analysis of Covariance with age as covariate and post-hoc t-test was used to search for differences in temperament scores between males and females. Also a table of percentile values corresponding to a raw score was created. RESULTS Internal consistency was excellent for the various temperaments (0.72-0.88). The factor analysis confirmed the five factor solution as the best factor solution. All TEMPS items were included in the final version of the scale in the Greek language. LIMITATIONS The study sample included subjects from the general population, but it is a convenient and not representative sample. Although the authors tried to select them on the basis of being mentally healthy and without a psychiatric history, there is always a degree of uncertainty. There is also always the possibility some of them to manifest a mental disorder in the future, thus being currently in a premorbid state. CONCLUSION The Greek version of the TEMPS-A, has good internal consistency and factor structure similar to what was found in other translations. Overall our results are in accord with the literature and in line with theoretical considerations as well as with empirical evidence.

Preliminary data concerning the reliability and psychometric properties of the Greek translation of the 20-item Subjective Well-Being Under Neuroleptic Treatment Scale (SWN-20)

BackgroundThe 20-item Subjective Well-Being Under Neuroleptic Treatment Scale (SWN-20) is a self-report scale developed in order to assess the well-being of patients receiving antipsychotic medication independent of the improvement in their psychotic symptoms. The current study reports on the reliability and the psychometric properties of the Greek translation of the SWN-20.MethodsA total of 100 inpatients or outpatients with schizophrenia (79 males and 21 females, aged 42.6 ± 11.35 years old) from 3 different facilities were assessed with the Positive and Negative Symptoms Scale (PANSS), the Calgary Depression Scale and the Simpson-Angus Scale, and completed the SWN-20. The statistical analysis included the calculation of Pearson product moment correlation coefficient, the Cronbach α and factor analysis with Varimax normalised rotation.ResultsThe SWN-20 had an α value equal to 0.79 and all the items were equal. The factor analysis revealed the presence of seven factors explaining 66% of total variance. The correlation matrix revealed a moderate relationship of the SWN-20 and its factors with the PANSS-Negative (PANSS-N), PANSS-General Psychopathology (PANSS-G), the Simpson-Angus and the Calgary scales, and no relationship to age, education and income class.DiscussionThe Greek translation of the SWN-20 is reliable, with psychometric properties close to the original scale.

Molecular cloning and sequence of gilthead sea bream (Sparus aurata) α-skeletal actin: tissue and developmental expression

In the present study, the Sparus aurata alpha-skeletal actin was cloned from a mixed larvae complementary DNA library. The clone isolated was 1523 bp long with an open reading frame of 1134 bp coding for a 377-amino acid protein. The deduced amino acid sequence of sea bream alpha-actin is identical to Fugu alpha-actin-1. The expression of alpha-actin was initiated at the onset of segmentation. In adult fish, alpha-actin is expressed predominantly in white and red muscle.