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Background and aim: We conducted an equivalence trial of quadruple non-bismuth "concomitant" and "hybrid" regimens for H. pylori eradication in a high clarithromycin resistance area. Methods: There were 321 treatment-naïve H. pylori-positive individuals in this multicenter clinical trial randomized to either the hybrid (esomeprazole 40 mg/bid, amoxicillin 1 g/bid for 7 days, then 7 days esomeprazole 40 mg/bid, amoxicillin 1 g/bid, clarithromycin 500 mg/bid, and metronidazole 500 mg/bid) or the concomitant regimen (all medications given concurrently bid for 10 days). Eradication was tested using histology and/or a 13C-urea breath test. Results: The concomitant regimen had 161 patients (90F/71M, mean 54.5 years, 26.7% smokers, 30.4% ulcer) and the hybrid regimen had 160 (80F/80M, mean 52.8 years, 35.6% smokers, 31.2% ulcer). The regimens were equivalent, by intention to treat 85% and 81.8%, (p = 0.5), and per protocol analysis 91.8% and 87.8%, (p = 0.3), respectively. The eradication rate by resistance, between concomitant and hybrid regimens, was in susceptible strains (97% and 97%, p = 0.6), clarithromycin single-resistant strains (86% and 90%, p = 0.9), metronidazole single-resistant strains (96% and 81%, p = 0.1), and dual-resistant strains (70% and 53%, p = 0.5). The side effects were comparable, except for diarrhea being more frequent in the concomitant regimen. Conclusions: A 14-day hybrid regimen is equivalent to a 10-day concomitant regimen currently used in high clarithromycin and metronidazole resistance areas. Both regimens are well tolerated and safe.
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By evaluating genetic variation across the entire genome, one can address existing questions in a novel way while raising new ones. The latter includes how different local environments influence adaptive and neutral genomic variation within and among populations, providing insights into local adaptation of natural populations and their responses to global change. Here, under a seascape genomic approach, ddRAD data of 4609 single nucleotide polymorphisms (SNPs) from 398 sardines (Sardina pilchardus) collected in 11 Mediterranean and one Atlantic site were generated. These were used along with oceanographic and ecological information to detect signals of adaptive divergence with gene flow across environmental gradients. The studied sardines constitute two clusters (FST = 0.07), a pattern attributed to outlier loci, highlighting putative local adaptation. The trend in the number of days with sea surface temperature above 19°C, a critical threshold for successful sardine spawning, was crucial at all levels of population structuring with implications on the species' key biological processes. Outliers link candidate SNPs to the region's environmental heterogeneity. Our findings provide evidence for a dynamic equilibrium in which population structure is maintained by physical and ecological factors under the opposing influences of migration and selection. This dynamic in a natural system warrants continuous monitoring under a seascape genomic approach that might benefit from a temporal and more detailed spatial dimension. Our results may contribute to complementary studies aimed at providing deeper insights into the mechanistic processes underlying population structuring. Those are key to understanding and predicting future changes and responses of this highly exploited species in the face of climate change.
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Genética de Población , Genómica , Mar Mediterráneo , Genoma , Adaptación Fisiológica/genética , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
BACKGROUND: The endoscopic management of benign short post-anastomotic ileocolonic stricture (PAICS) that is refractory to primary and secondary treatment modalities remains challenging. The lumen-apposing metal stent (LAMS) is a novel device recently developed for therapeutic gastrointestinal endoscopy. LAMSs have demonstrated significantly better results with regard to stent migration than fully covered self-expandable metal stents (FCSEMSs). CASE SUMMARY: This article presents six cases of symptomatic PAICS successfully treated with a LAMS and a review of the relevant literature. We report a life-saving technique not previously documented and the use of technology to improve patient outcomes. The six patients (median age, 75 years) suffered from vomiting, constipation and recurrent abdominal pain, with symptoms starting 23-25 wk post-surgery. The median stricture length was 1.83 cm. All six patients underwent successful and uneventful bi-flanged metal stent (BFMS)-LAMS placement for benign PAICS. All patients remained asymptomatic during the three months of stent indwelling and up to a median of 7 mo after stent removal. According to the literature, the application of LAMS for PAICS is associated with a < 10% risk of migration and a < 5% risk of bleeding. Conversely, FCSEMS has a high migration rate (15%-50%). CONCLUSION: The evolving role of interventional endoscopy and the availability of LAMSs provide patients with minimally invasive treatment options, allowing them to avoid more invasive surgical interventions. The BFMS (NAGI stent) is longer and larger than the prototype AXIOS-LAMS, which should be considered in the management of short ileocolonic post-anastomotic strictures longer than 10 mm and shorter than 30 mm.
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The Tetraodontidae family encompasses several species which attract scientific interest in terms of their ecology and evolution. The silver-cheeked toadfish (Lagocephalus sceleratus) is a well-known "invasive sprinter" that has invaded and spread, in less than a decade, throughout the Eastern and part of the Western Mediterranean Sea from the Red Sea through the Suez Canal. In this study, we built and analysed the first near-chromosome level genome assembly of L. sceleratus and explored its evolutionary landscape. Through a phylogenomic analysis, we positioned L. sceleratus closer to T. nigroviridis, compared to other members of the family, while gene family evolution analysis revealed that genes associated with the immune response have experienced rapid expansion, providing a genetic basis for studying how L. sceleratus is able to achieve highly successful colonisation. Moreover, we found that voltage-gated sodium channel (NaV 1.4) mutations previously connected to tetrodotoxin resistance in other pufferfishes are not found in L. sceleratus, highlighting the complex evolution of this trait. The high-quality genome assembly built here is expected to set the ground for future studies on the species biology.
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High-performance computing (HPC) systems have become indispensable for modern marine research, providing support to an increasing number and diversity of users. Pairing with the impetus offered by high-throughput methods to key areas such as non-model organism studies, their operation continuously evolves to meet the corresponding computational challenges. Here, we present a Tier 2 (regional) HPC facility, operating for over a decade at the Institute of Marine Biology, Biotechnology, and Aquaculture of the Hellenic Centre for Marine Research in Greece. Strategic choices made in design and upgrades aimed to strike a balance between depth (the need for a few high-memory nodes) and breadth (a number of slimmer nodes), as dictated by the idiosyncrasy of the supported research. Qualitative computational requirement analysis of the latter revealed the diversity of marine fields, methods, and approaches adopted to translate data into knowledge. In addition, hardware and software architectures, usage statistics, policy, and user management aspects of the facility are presented. Drawing upon the last decade's experience from the different levels of operation of the Institute of Marine Biology, Biotechnology, and Aquaculture HPC facility, a number of lessons are presented; these have contributed to the facility's future directions in light of emerging distribution technologies (e.g., containers) and Research Infrastructure evolution. In combination with detailed knowledge of the facility usage and its upcoming upgrade, future collaborations in marine research and beyond are envisioned.
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Metodologías Computacionales , Biología Marina , Acuicultura/métodos , Biotecnología/métodos , Biología Marina/métodos , Programas InformáticosRESUMEN
The Mediterranean monk seal (Monachus monachus) is a flagship species for marine conservation, but important aspects of its life history remain unknown. Concerns over imminent extinction motivated a nuclear DNA study of the species in its largest continuous subpopulation in the eastern Mediterranean Sea. Despite recent evidence of partial subpopulation recovery, we demonstrate that there is no reason for complacency, as the species still shares several traits that are characteristic of a critically endangered species: Mediterranean monk seals in the eastern Mediterranean survive in three isolated and genetically depauperate population clusters, with small effective population sizes and high levels of inbreeding. Our results indicated male philopatry over short distances, which is unexpected for a polygynous mammal. Such a pattern may be explained by the species' unique breeding behavior, in which males defend aquatic territories near breeding sites, while females are often forced to search for new pupping areas. Immediate action is necessary to reverse the downward spiral of population decline, inbreeding accumulation and loss of genetic diversity. We propose concrete conservation measures for the Mediterranean monk seal focusing on reducing anthropogenic threats, increasing the population size and genetic diversity, and thus improving the long-term prospects of survival.
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Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Phocidae , Distribución Animal/fisiología , Animales , Caniformia/clasificación , Conservación de los Recursos Naturales/historia , ADN Mitocondrial/análisis , Demografía , Ecosistema , Especies en Peligro de Extinción/historia , Pruebas Genéticas/veterinaria , Variación Genética/fisiología , Grecia/epidemiología , Historia del Siglo XX , Mar Mediterráneo , Densidad de Población , Dinámica Poblacional/historia , Phocidae/genéticaRESUMEN
The effects of the abrupt input of high quantities of dissolved inorganic nitrogen and phosphorus on prokaryotic and eukaryotic microbial plankton were investigated in an attempt to simulate the nutrient disturbances caused by eutrophication and climate change. Two nutrient levels were created through the addition of different quantities of dissolved nutrients in a mesocosm experiment. During the developed blooms, compositional differences were found within bacteria and microbial eukaryotes, and communities progressed towards species of faster metabolisms. Regarding the different nutrient concentrations, different microbial species were associated with each nutrient treatment and community changes spanned from the phylum to the operational taxonomic unit (OTU) level. Network analyses revealed important differences in the biotic connections developed: more competitive relationships were established in the more intense nutrient disturbance and networks of contrasting complexity were formed around species of different ecological strategies. This work highlights that sudden disturbances in water column chemistry lead to the development of entirely different microbial food webs with distinct ecological characteristics.
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Eucariontes , Microbiota , Código de Barras del ADN Taxonómico , Eutrofización , Nitrógeno , Nutrientes , FósforoRESUMEN
Kotschy's Gecko, Mediodactylus kotschyi, is a small gecko native to southeastern Europe and the Levant. It displays great morphological variation with a large number of morphologically recognized subspecies. However, it has been suggested that it constitutes a species complex of several yet unrecognized species. In this study, we used multilocus sequence data (three mitochondrial and three nuclear gene fragments) to estimate the phylogenetic relationships of 174 specimens from 129 sampling localities, covering a substantial part of the distribution range of the species. Our results revealed high genetic diversity of M. kotschyi populations and contributed to our knowledge about the phylogenetic relationships and the estimation of the divergence times between them. Diversification within M. kotschyi began approximately 15 million years ago (Mya) in the Middle Miocene, whereas the diversification within most of the major clades have been occurred in the last 5â¯Mya. Species delimitation analysis suggests there exists five species within the complex, and we propose to tentatively recognize the following taxa as full species: M. kotschyi (mainland Balkans, most of Aegean islands, and Italy), M. orientalis (Levant, Cyprus, southern Anatolia, and south-eastern Aegean islands), M. danilewskii (Black Sea region and south-western Anatolia), M. bartoni (Crete), and M. oertzeni (southern Dodecanese Islands). This newly recognized diversity underlines the complex biogeographical history of the Eastern Mediterranean region.
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Sitios Genéticos , Variación Genética , Lagartos/clasificación , Lagartos/genética , Filogenia , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Geografía , ARN Ribosómico 16S/genética , Alineación de Secuencia , Especificidad de la Especie , Factores de TiempoRESUMEN
BACKGROUND: Endoscopic submucosal dissection (ESD) requires special skills and a long procedure time for a quality-controlled procedure. A universal training system remains to be established. Hands-on courses in animal models before advancing to the human colon appear to be essential, especially in Europe. The learning curve is a prerequisite in ESD, in order to improve technical outcomes and decrease the rate of procedural adverse events. METHODS: In the experimental research center of ELPEN Pharmaceuticals, 18 European endoscopists, inexperienced at ESD, performed gastric ESDs in porcine models. The course lasted two days and was conducted under the supervision of experts. RESULTS: A total of 72 of 76 ESDs were completed en bloc (94.7%). The procedural time and cutting speed differed significantly between the first and second day: 48±4.4 vs. 43±4.8 min (P=0.0045), and 1.38±0.20 vs. 1.63±0.23 cm2/min (P=0.0033), respectively. The complications were not significantly different between the two groups: five (13.88%) vs. four (11%) episodes of bleeding (P>0.05). The perforation rate was similar, at two episodes per day (5.55%). We documented an acceptable rate of en bloc resections and complications. CONCLUSION: ESD demands a new level of endoscopic skills in Europe. A formal sequential training program, using porcine models, may benefit countries with a low volume of cases.
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BACKGROUND: Elucidating the patterns of the Atlantic Bluefin tuna [ABFT, Thunnus thynnus (Linnaeus, 1758)] population structure constitutes a challenging task of great importance. Most of the unique challenges stem from its biology, as well as the attributes of the marine realm in which it disperses. Accurate information is urgently needed for stock assessment, and the identification of critical features to the persistence and adaptation of populations in order to formulate and adopt effective strategies for ABFT conservation and management. Conclusions of a great number of ABFT genetic studies on the Mediterranean Sea stock structure are rather controversial and not yet conclusive. In this study, ABFT genomic diversity was investigated in the Mediterranean Sea, which is the most important area for the species' reproduction. RESULTS: Analyzing genome-wide SNPs and microsatellites from ABFT samples collected throughout the Mediterranean Sea did not provide strong evidence of genetic structure, pointing towards the existence of a single panmictic unit. An alternative view would recognize a failure to reject the null hypothesis of a panmictic unit as an effect of the study's sampling design, the type of markers used, and the effectiveness/suitability of analysis methods in respect to the species biological characteristics or any combination of the above. CONCLUSIONS: Unravelling the drivers of ABFT population diversity would require the consideration of important aspects of the species spawning behavior for the determination of the appropriate sampling design. Novel approaches and methods of analysis that will bring together experts in genetics/-omics, ecology and oceanography are deemed necessary. Analyzing ABFT genetic data under the discipline of seascape genetics could provide the analysis framework under which major abiotic and biotic forces controlling ABFT recruitment could be identified, elucidating the complicated population dynamics of the species, while multiple and continuous fisheries monitoring should in all cases be considered as a prerequisite in order to achieve efficient and long-term ABFT conservation.
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BACKGROUND: Currently only a few studies compare sequential and concomitant non-bismuth Helicobacter pylori therapies referring to high antibiotic resistance populations. MATERIALS AND METHODS: This multicenter prospective randomized clinical trial included 353 H. pylori positive, treatment naïve, patients. All patients had positive CLO-test and/or histology and culture. They received sequential (esomeprazole 40mg, amoxicillin 1g/bid for 5days, followed by 5days of esomeprazole 40mg, clarithromycin 500mg and metronidazole 500mg bid), or concomitant treatment (all drugs taken concomitantly bid for 10days). Eradication was confirmed by (13)C-urea breath test or histology 4-6weeks after treatment. Adverse events and adherence were evaluated. RESULTS: Allocated to concomitant were 175 (72F/103M, mean 52.3years, 38.3% smokers, 25.7% ulcer disease) and 178 (87F/91M, mean 52years, 31% smokers, 19.1% ulcer disease) patients to sequential treatment. There were 303/353 (85.8%) positive cultures, with the following resistances: 34% metronidazole, 27.7% clarithromycin, and 7.9% dual. Eradication rates were, respectively, 89.1% (156/175) vs. 78.7% (140/178) by intention to treat (p=0.01, 95% CI=2.7-18) and 93.4%(156/167) vs. 82.8% (140/169) per protocol (p=0.004, 95% CI=3.6-17.6). Overall, adherence was (98.9%, 95% CI=97-100). Eradication rates according to resistance were the following: dual susceptible strains 67/69 (97.1%), 62/67 (92%) (p=0.4), metronidazole single resistant 38/39 (97.4%), 31/39 (79.5%) (p=0.03, 95% CI=3.5-33), clarithromycin single resistant 25/28 (89.3%), 26/31 (83.9%) (p=0.8), and dual resistant 9/12 (75%), 4/11 (36.4%) (p=0.1) for concomitant and sequential regimens, respectively. Side effects were comparable among regimens, except from diarrhea being more frequent among patients treated with concomitant treatment. CONCLUSIONS: Concomitant treatment eradication rate overcomes 90% per protocol and has a significant advantage over sequential therapy. This is probably due to its better efficacy on metronidazole resistant strains. Both regimens were well tolerated and safe.
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Amoxicilina/administración & dosificación , Antibacterianos/administración & dosificación , Claritromicina/administración & dosificación , Dispepsia/tratamiento farmacológico , Esomeprazol/administración & dosificación , Infecciones por Helicobacter/tratamiento farmacológico , Metronidazol/administración & dosificación , Úlcera Péptica/tratamiento farmacológico , Inhibidores de la Bomba de Protones/administración & dosificación , Adulto , Anciano , Biopsia , Pruebas Respiratorias , Isótopos de Carbono , Farmacorresistencia Bacteriana , Quimioterapia Combinada , Dispepsia/microbiología , Femenino , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/patología , Helicobacter pylori , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/microbiología , Antro Pilórico/patología , Urea/metabolismoRESUMEN
Water frogs of the genus Pelophylax (previous Rana) species have been much studied in Europe for their outstanding reproductive mechanism in which sympatric hybridization between genetically distinct parental species produces diverse genetic forms of viable hybrid animals. The most common hybrid is P. esculentus that carries the genomes of both parental species, P. ridibundus and P. lessonae, but usually transfers the whole genome of only one parent to its offsprings (hybridogenesis). The evolutionary cost of transfer of the intact genome and hence the hemiclonal reproduction is the depletion of heterozygosity in the hybrid populations. Pelophylax esculentus presents an excellent example of the long-term sustained hybridization and hemiclonal reproduction in which the effects of the low genetic diversity are balanced through the novel mutations and periodic recombinations. In this study, we analyzed the mitochondrial (mt) and microsatellites DNA variations in hybrid Pelophylax populations from southern parts of the Pannonian Basin and a north-south transect of the Balkan Peninsula, which are home for a variety of Pelophylax genetic lineages. The mtDNA haplotypes found in this study corresponded to P. ridibundus and P. epeiroticus of the Balkan - Anatolian lineage (ridibundus-bedriagae) and to P. lessonae and a divergent lessonae haplotype of the lessonae lineage. The mtDNA genomes showed considerable intraspecific variation and geographic differentiation. The Balkan wide distributed P. ridibundus was found in all studied populations and its nuclear genome, along with either the lessonae or the endemic epeiroticus genome, in all hybrids. An unexpected finding was that the hybrid populations were invariably heteroplasmic, that is, they contained the mtDNA of both parental species. We discussed the possibility that such extensive heteroplasmy is a result of hybridization and it comes from regular leakage of the paternal mtDNA from a sperm of one species that fertilizes eggs of another. In this case, the mechanisms that protect the egg from heterospecific fertilization and further from the presence of sperm mtDNA could become compromised due to their differences and divergence at both, mitochondrial and nuclear DNA. The heteroplasmy once retained in the fertilized egg could be transmitted by hybrid backcrossing to the progeny and maintained in a population over generations. The role of interspecies and heteroplasmic hybrid animals due to their genomic diversity and better fitness compare to the parental species might be of the special importance in adaptations to miscellaneous and isolated environments at the Balkan Peninsula.
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A common source of disturbance for coastal aquatic habitats is nutrient enrichment through anthropogenic activities. Although the water column bacterioplankton communities in these environments have been characterized in some cases, changes in α-diversity and/or the abundances of specific taxonomic groups across enriched habitats remain unclear. Here, we investigated the bacterial community changes at three different nutrient-enriched and adjacent undisturbed habitats along the north coast of Crete, Greece: a fish farm, a closed bay within a town with low water renewal rates, and a city port where the level of nutrient enrichment and the trophic status of the habitat were different. Even though changes in α-diversity were different at each site, we observed across the sites a common change pattern accounting for most of the community variation for five of the most abundant bacterial groups: a decrease in the abundance of the Pelagibacteraceae and SAR86 and an increase in the abundance of the Alteromonadaceae, Rhodobacteraceae, and Cryomorphaceae in the impacted sites. The abundances of the groups that increased and decreased in the impacted sites were significantly correlated (positively and negatively, respectively) with the total heterotrophic bacterial counts and the concentrations of dissolved organic carbon and/or dissolved nitrogen and chlorophyll α, indicating that the common change pattern was associated with nutrient enrichment. Our results provide an in situ indication concerning the association of specific bacterioplankton groups with nutrient enrichment. These groups could potentially be used as indicators for nutrient enrichment if the pattern is confirmed over a broader spatial and temporal scale by future studies.
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Bacterias/clasificación , Bacterias/genética , Biota , Ecosistema , Agua de Mar/microbiología , Clorofila/análisis , Clorofila A , ADN Bacteriano/química , ADN Bacteriano/genética , Grecia , Datos de Secuencia Molecular , Compuestos de Nitrógeno/análisis , Compuestos Orgánicos/análisis , Agua de Mar/química , Análisis de Secuencia de ADNRESUMEN
The phylogenetic relationships among species of the Labeobarbus genus (Teleostei, Cyprinidae) which comprises large body-sized hexaploid taxa were inferred using complete cytochrome b mitochondrial gene sequences. Molecular data suggest two main evolutionary groups which roughly correspond to a Northern (Middle East and Northwest Africa) and a sub-Saharan lineage. The splitting of the African hexaploids from their Asian ancestors and their subsequent diversification on the African continent occurred in the Late Miocene, a period in which other cyprinins also invaded Africa and radiated in the Mediterranean region. Finally, systematic implications of these results to the taxonomic validity of genera or subgenera such as Varicorhinus, Kosswigobarbus, Carasobarbus and Capoeta are further discussed.
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Cyprinidae/genética , ADN Mitocondrial/genética , Evolución Molecular , Filogenia , África , Animales , Teorema de Bayes , Cyprinidae/clasificación , Especiación Genética , Haplotipos , Funciones de Verosimilitud , Región Mediterránea , Medio Oriente , Modelos Genéticos , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: The aim of this study was to retrospectively evaluate the short-and long-term effectiveness of different methods of endoscopic treatment for bleeding Dieulafoy's lesions. METHODS: Patients were allocated into 2 groups according to the hemostatic method applied: (1) injection group (epinephrine and/or ethanolamine oleate), and (2) thermal coagulation group (heat probe), either alone or combined with epinephrine injection. The combination of epinephrine and ethanolamine oleate was used in 5 patients, epinephrine alone in 3, ethanolamine oleate alone in one, heat probe and epinephrine in 8, and heat probe alone in 1 patient. RESULTS: Dieulafoy's lesions were found in 18 (1%) of 1750 patients with acute nonvariceal upper GI bleeding. Comorbid conditions were present in 5 (28%) patients. Initial hemostasis was achieved endoscopically in 13 patients (72%) and permanent hemostasis in 17 patients (94%). Bleeding recurred in 5 patients (2 with concomitant disease) in the injection group; 3 were successfully retreated by heat probe coagulation and epinephrine injection, 1 with hemoclip application and 1 by surgery. There was no recurrent bleeding in thermal treatment group. Thermal treatment was significantly superior to injection (p = 0.0029). CONCLUSIONS: Endoscopic thermal coagulation with or without epinephrine injection should be the initial treatment of choice for Dieulafoy's lesions. Mortality is lowest in patients with no significant comorbidity and an unremarkable medical history.