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Coastal and demersal chondrichthyans, such as the small-spotted catshark, are expected to exhibit genetic differentiation in areas of complex geomorphology like the Mediterranean Basin because of their limited dispersal ability. To test this hypothesis, we used a fragment of the mitochondrial cytochrome c oxidase subunit I gene and 12 nuclear microsatellite loci in order to investigate the genetic structure and historical demography of this species, and to identify potential barriers to gene flow. Samples were collected from the Balearic Islands, the Algerian Basin, the Ionian Sea, the Corinthian Gulf and various locations across the Aegean Sea. Additional sequences from the Atlantic and the Levantine Basin retrieved from GenBank were included in the mitochondrial DNA analysis. Both mitochondrial and nuclear microsatellite DNA data revealed a strong genetic subdivision, mainly between the western and eastern Mediterranean, whereas the Levantine Basin shared haplotypes with both areas. The geographic isolation of the Mediterranean basins seems to enforce the population genetic differentiation of the species, with the deep sea acting as a strong barrier to its dispersal. Contrasting historical demographic patterns were also observed in different parts of the species' distribution, most notably a population growth trend in the western Mediterranean/Atlantic area and a slight decreasing one in the Aegean Sea. The different effects of the Pleistocene glacial periods on the habitat availability may explain the contrasting demographic patterns observed. The current findings suggest that the small-spotted catshark exhibits several genetic stocks in the Mediterranean, although further study is needed.

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The European sea bass (Dicentrarchus labrax) is, along with the gilthead sea bream (Sparus aurata), one of the most extensively cultured species in European aquaculture productions. Massive mortalities may be caused by bacterial or viral infections in intensive aquaculture production. Evaluation of the efficacy of an oral vaccine against Vibrio anguillarum (Aquavac Vibrio Oral) in sea bass revealed specific immune gene expression profiles in the gut as well as protection of fish. In the present study, we performed RNA SEQ in two different tissues: the hind gut and the head kidney. For each tissue, one control sample (where a sample presents a pool of four to five individuals) and one sample after oral vaccine against V. anguillarum were submitted to 454 next-generation sequencing. In total, 269,043 sequences were obtained, 143,007 for head kidney and 125,036 for gut. The read lengths ranged from 40 to 706 bp with an average length of 348 bp. The total number of clustered sequences for head kidney is accounting to 49,089 (∼34 %) and for gut to 71,676 (~57 %). Differential expression was detected for 496 transcripts in head kidney and for 336 in gut. The results not only enrich the present collection of expressed sequence tag sequences including rare transcripts like leukocyte immune-type receptors, cullin, or supervillin but also show the efficacy of oral vaccination against V. anguillarum.

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Eight polymorphic microsatellites were isolated from the Greek smooth newt (Lissotriton vulgaris graecus) using a microsatellite enrichment protocol and selective hybridization with a biotinylated (AC)(11) probe. The loci showed different variation patterns in a single breeding population (32 individuals) with mean number of alleles at 5.0 and mean observed heterozygosity at 0.520. The amplification success also in the nominotypical subspecies favours the use of these microsatellite loci in population genetic analyses as well as in the study of contact zones between smooth newt subspecies.

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Eighteen microsatellite loci (13 di- and 5 tri-repeats) were isolated from swordfish and characterized in two populations from the Atlantic Ocean and Mediterranean Sea. The number of alleles per locus ranged from two to 29 and the observed heterozygosity from 0.302 to 0.953. All but one locus conformed to Hardy-Weinberg expectations and there was no evidence for linkage disequilibrium between loci.

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Eleven microsatellite loci were developed in the European anchovy, Engraulis encrasicolus, and tested in samples from two geographically distant populations (Atlantic and Mediterranean Sea). Number of alleles ranged from eight to 28 and observed heterozygosity from 0.440 to 0.920. There was no evidence of linkage disequilibrium, although two loci are indeed linked. All loci were in Hardy-Weinberg equilibrium, except for one locus in the Atlantic and two loci in the Mediterranean sample. These three loci plus two more showed evidence for null alleles.

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Eleven microsatellites have been characterized for Triturus macedonicus. Nine loci showed different variation patterns in a sample of 40 individuals from a single breeding pond in Zagori province (Greece), with an average number of 4.2 alleles per locus and an expected heterozygosity ranging from 0.1199 to 0.8079. Distinct cross-priming amplification rates were recovered on four additional crested newt species. Two monomorphic T. macedonicus loci were polymorphic in other Triturus species. The microsatellites developed herein could be a useful intraspecific genetic tool to undertake fine-scale population genetic analyses as well as in the study of contact zones between crested newt species.

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Cyrtopodion kotschyi is a small gecko, widely distributed on the islands of the Aegean archipelago and the adjacent mainland. We unveiled the phylogeography of the species by using a portion of the cytochrome oxidase I mitochondrial DNA gene from 35 insular and mainland populations. The distinct geographic distribution of the major clades of the phylogenetic tree and its topology suggest a spatial and temporal sequence of phylogenetic separations that coincide with some major paleogeographical separations during the geological history of the Aegean and support a mainly vicariant pattern of differentiation. The separation times and 95% confidence limits among the different clades were estimated according to two different paleogeographical scenarios. The very high interpopulation genetic divergence (up to 20% uncorrected pairwise distances) and the better concordance between paleogeographical and phylogenetic separations for one of the scenarios suggest that species differentiation started during Miocene (about 10 Mya) due to the fragmentation of the united landmass of "Agais" that was Aegean at that time.

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The phylogeographic structure of the brown hare (Lepus europaeus) was studied by analysing mtDNA control region sequences of 98 individuals from continental and insular Greece, Bulgaria, Cyprus and northern Israel, together with 44 published sequences from Italy and central Europe. We found two distinct clades separated by an average nucleotide divergence of 6.6%, which may correspond to a Balkan and to an Asia Minor refugium. The estimated time of separation of the two clades was dated back to 105,000- 490,000 years ago. These two clades coexist in the area of northeastern Greece and Bulgaria, most likely as a result of a post-glacial northward expansion. Within the southern Balkan refugium, network analyses showed geographical structuring, which supports the hypothesis of several isolated Late Pleistocene populations. The central European and Italian populations appear to have originated from a non-detected northern Balkan population that was genetically closely related to some northern Greek populations, as a result of postglacial expansion, translocations or a combination of both. Moreover, several cases of ancient and recent translocations by humans were detected, especially for some island populations, while the eastern Aegean islands off the Asia Minor coast were most likely colonized naturally through Late Pleistocene land bridge connection. The genetic analysis presented here provides a framework for designing proper conservation and management guidelines for this species.

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BACKGROUND: Cholera toxin, and Escherichia coli heat labile (LT) and heat stable (STa) enterotoxins induce small intestinal secretion in part by activating enteric nerves. Igmesine is a novel sigma receptor ligand that inhibits neurally mediated secretion. AIMS: To assess the antisecretory potential of igmesine in cholera toxin, LT, and STa induced water and electrolyte secretion using an in vivo rat model of jejunal perfusion. METHODS: After pretreatment with igmesine, 0.03-10 mg/kg intravenously, jejunal segments of anaesthetised, adult male Wistar rats were incubated with cholera toxin (25 microg), LT (25 microg), or saline. Jejunal perfusion with a plasma electrolyte solution containing a non-absorbable marker was undertaken. In some cases 200 microg/l STa was added to the perfusate. After equilibration, net water and electrolyte movement was determined. In additional experiments rats received igmesine, intravenously or intrajejunally, after exposure to cholera toxin. RESULTS: Cholera toxin induced net water secretion was inhibited by 1 mg/kg igmesine (median -120 versus -31 microl/min/g, p<0.001). LT and STa induced secretion were also inhibited by 1 mg/kg igmesine (-90 versus -56, p<0.03; and -76 versus -29, p<0.01, respectively). Igmesine reduced established cholera toxin induced secretion. CONCLUSION: The sigma ligand, igmesine, inhibits neurally mediated enterotoxigenic secretion. Its ability to inhibit established secretion makes it an agent with therapeutic potential.

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An increased frequency of reflux events and a prolonged acid clearance have been shown in gastroesophageal reflux (GER) patients with a hiatal hernia as compared to those without. The objective of the present study was to further investigate esophageal motility and patterns of reflux in GER patients, in relation to the presence or absence of hiatal hernia. Esophageal manometry and ambulatory 24-hr esophageal pH-metry were used in 42 patients with GER and 18 controls. Eighteen of the patients were considered to have a nonreducing hiatal hernia on endoscopy. Hiatal hernia patients showed a higher extent of reflux (total composite score, P = 0.016; total reflux time, P = 0.008, reflux time in supine position, P = 0.024; reflux time in upright position, P = 0.008), a lower frequency of reflux events (P = 0.005), a more severe esophagitis on endoscopy (P < 0.01) and a lower amplitude of peristalsis at 5 cm proximal to LES (P = 0.0009) as compared to patients without hiatal hernia. The amplitude of peristalsis at the distal esophagus was inversely related to the extent of reflux (P = 0.024). Acid clearance was also significantly prolonged in the hernia subgroup (P = 0.011). Although LES resting pressure did not differ significantly between the two subgroups of patients, it was inversely related to the extent of reflux in the patients with hiatal hernia (P = 0.0005). It is concluded, that GER patients with hiatal hernia present with an increased amount of reflux and more severe esophagitis, which results in more severely impaired esophageal peristalsis as compared to patients without hernia. Prolonged acid clearance and impaired esophageal emptying observed in patients with hiatal hernia could be the result of both the presence of the hernia itself and the reduced peristaltic activity of the esophagus.

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Thirty-five patients with gastroesophageal reflux (GER) proved on ambulatory esophageal hydrogen monitoring were surgically treated by a floppy Nissen fundoplication. Postoperatively, reflux and symptoms related to it were almost completely abolished. Transient bloating syndrome was observed in five instances. The operation significantly improved esophagitis (p < 0.01), increased lower esophageal sphincter pressure (p < 0.01) and increased amplitude of esophageal peristalsis (p < 0.01). However, postoperative motility of the esophagus as detected by manometry was still impaired as compared with that for the control group. Delayed esophageal transit did not improve postoperatively, although no dysphagia was accounted. Impaired esophageal motility in GER was associated with delayed gastric emptying, which, however, improved postoperatively. It is concluded that esophageal and gastric motor abnormalities are rather primary disorders in GER. After successful fundoplication, esophageal dysmotility, aggravated by reflux esophagitis, improves to some extent, while gastric emptying is enhanced.

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UNLABELLED: In this study, our objective was to examine prospectively, by endoscopy and histology of the esophageal mucosa, the severity of reflux esophagitis and any possible correlation between endoscopic and histological findings on the one hand, and manometric and 24-h ambulatory pH-metry measurements on the other. Forty-two patients with gastroesophageal reflux were prospectively examined. The results were compared with those of 18 healthy controls. Methods used were: 1) upper alimentary endoscopy and grading of severity of esophagitis, 2) esophageal mucosa biopsies, to estimate severity of esophagitis on histology, 3) standard esophageal manometry, by using a water perfused catheter with four side holes, and 4) standard 24-h ambulatory esophageal pH-metry. RESULTS: The severity of esophagitis as determined by both endoscopy and histology was significantly inversely related to the amplitude (p < 0.001) and duration (p < 0.01) of esophageal peristalsis at 5 cm proximal to LES; it was significantly related to the pH-metry total composite score (p < 0.001 for endoscopy, p < 0.05-0.01 for histology), the total reflux time (p < 0.001 for endoscopy, p < 0.01 for histology), the duration of longest reflux episode (p < 0.001 for endoscopy, p < 0.01 for histology), the number of reflux episodes lasting more than 5 min (p < 0.05 for endoscopy), and the frequency-duration index of reflux episodes (p < 0.001 for endoscopy, p < 0.01 for histology). Furthermore, strength reduction of peristalsis (< 60 mm Hg x s) was associated with acid exposure greater than 40%, in esophagitis patients. We conclude that the severity of reflux esophagitis, not only through endoscopy but also histologically, is related to the amount of reflux, as expressed by the duration and frequency of the reflux episodes. A very high amount of reflux is in turn associated with impairment of the esophageal body motility, as expressed by the amplitude and strength of esophageal body peristalsis.

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A case of colonic varices manifesting with rectal bleeding in a young patient is presented. There was no evidence of portal hypertension or any other cause. Familial history was also negative. Diagnosis was established by barium enema, colonoscopy and angiography. On colonoscopy, varices involved the entire colon. At operation, dilatation of the subserosal small veins of the entire small and large bowel was confirmed. The patient underwent a subtotal colectomy with ileorectal anastomosis with satisfactory result.

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