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1.
Animal ; 17(3): 100723, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36801549

RESUMEN

Genetic architecture of sheep reproduction is increasingly gaining scientific interest due to the major impact on sheep production systems. In the present study, we conducted pedigree-based analyses and genome-wide association studies using the Illumina Ovine SNP50K BeadChip to explore the genetic mechanisms underlying the reproduction of the highly prolific Chios dairy sheep. First lambing age, total prolificacy and maternal lamb survival were selected as representative reproductive traits and estimated as significantly heritable (h2 = 0.07-0.21) with no evident genetic antagonism among traits. We identified novel genome-wide and suggestive significant single-nucleotide polymorphisms (SNPs) on chromosomes 2 and 12 associated with age at first lambing. The new variants detected on chromosome 2 span a region of 357.79 kb with high pairwise linkage disequilibrium estimates (r2 = 0.8-0.9). Functional annotation analysis revealed candidate genes, such as the collagen-type genes and the Myostatin gene, that participate in osteogenesis, myogenesis, skeletal and muscle mass development resembling the functionality of major genes affecting the ovulation rate and prolificacy. Additional functional enrichment analysis associated the collagen-type genes with multiple uterine-related disfunctions, such as cervical insufficiency, uterine prolapse and abnormalities of the uterine cervix. Several genes (e.g., KAZN, PRDM2, PDPN, LRRC28) localised close to the SNP marker on chromosome 12 were grouped in annotation enrichment clusters majorly involved in developmental and biosynthetic pathways, apoptosis, and nucleic acid-templated transcription. Our findings may further contribute to unravel the genomic regions that are important for sheep reproduction and could be incorporated into future selective breeding programmes.


Asunto(s)
Estudio de Asociación del Genoma Completo , Reproducción , Femenino , Ovinos/genética , Animales , Estudio de Asociación del Genoma Completo/veterinaria , Reproducción/genética , Genoma , Fenotipo , Genómica , Polimorfismo de Nucleótido Simple , Colágeno/genética
2.
Int J Surg Case Rep ; 67: 91-94, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32045860

RESUMEN

INTRODUCTION: Tumor- or treatment- induced thrombocytopenia in solid cancer patients is common. In the postoperative setting, diagnosis of thrombocytopenia become more complex as infection, sepsis, drugs and transfusion come also into the equation. PRESENTATION OF CASE: Herein, the case an otherwise-healthy 71-year-old male patient with a sizable recurrent malignant retroperitoneal tumor under pazopanib admitted with colon perforation and submitted to emergency left colectomy with end transverse colostomy is presented. Immediate postoperative period characterized by massive primary tumor growth and isolated acute severe thrombocytopenia. The patient treated with combined prednisone, IVIg and platelets transfusion along with medication discontinuation with no response. DISCUSSION: Sepsis-, drug- and heparin-induced thrombocytopenia, disseminated intravascular coagulopathy and secondary (sepsis-, drug-, transfusion- or tumor-induced) immune thrombocytopenia (ITP) were included in the differential diagnosis. Based on exclusion, secondary drug- or tumor-induced ITP was the most prominent diagnosis. Concomitant presentation of thrombocytopenia along with massive primary tumor growth made Kasabach-Merritt syndrome also a probable diagnosis. However, neither secondary ITP nor Kasabach-Merritt syndrome has previously been associated with a retroperitoneal tumor in the literature. CONCLUSION: Although management of thrombocytopenia depends on etiology, in our patient's case the diagnosis of secondary ITP and directed management did not result in a successful outcome.

3.
J Dairy Sci ; 100(5): 3539-3547, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28318592

RESUMEN

Caseins are widely used for species identification of dairy products. Isoelectric focusing (IEF) of para-κ-casein peptide is used as the official German method for the differentiation between caprine (isoform A) and ovine (isoform B) dairy products, based on their different isoelectric points. The discrimination between Greek goat and ewe dairy products using IEF has, however, been shown to be problematic because of the existence of the ewe isoform in milk from Greek indigenous dairy goats. This could be due to nucleotide polymorphisms within the goat κ-casein gene of Greek indigenous breeds, which alter the isoelectric point of the para-κ-casein peptide and lead to false positive results. Previous DNA analysis of the goat κ-casein gene has shown high levels of polymorphism; however, no such information is available for Greek indigenous dairy goats. Therefore, 87 indigenous dairy goats were sequenced at exon IV of κ-casein gene. In total, 9 polymorphic sites were detected. Three nonsynonymous point mutations were identified, which change the isoelectric point of the goat para-κ-casein peptide so that it appears identical to that of the ewe peptide. Ten composite genotypes were reconstructed and 6 of them included the problematic point mutations. For the verification of genetic results, IEF was carried out. Both goat and ewe patterns appeared in the problematic genotypes. The frequency of these genotypes could be characterized as moderate (0.23) to high (0.60) within Greek indigenous breeds. However, this is not an issue restricted to Greece, as such genotypes have been detected in various non-Greek goat breeds. In conclusion, IEF based on the official German method is certainly inappropriate for ovine and caprine discrimination concerning Greek dairy goat products, and consequently a new method should be established.


Asunto(s)
Caseínas/genética , Cabras , Ovinos , Animales , Leche/química , Polimorfismo Genético
4.
IEEE J Biomed Health Inform ; 17(1): 30-7, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23193318

RESUMEN

In this paper, we present the design and development of a pervasive health system enabling self-management of chronic patients during their everyday activities. The proposed system integrates patient health monitoring, status logging for capturing various problems or symptoms met, and social sharing of the recorded information within the patients community, aiming to facilitate disease management. A prototype is implemented on a mobile device illustrating the feasibility and applicability of the presented work by adopting unobtrusive vital signs monitoring through a wearable multi-sensing device, a service oriented architecture for handling communication issues, and popular micro-blogging services. Furthermore, a study has been conducted with 16 hypertensive patients, in order to investigate the user acceptance, the usefulness, and the virtue of the proposed system. The results show that the system is welcome by the chronic patients who are especially willing to share healthcare information, and easy to learn and use, while its features have been overall regarded by the patients as helpful for their disease management and treatment.


Asunto(s)
Redes de Comunicación de Computadores , Informática Médica/métodos , Monitoreo Fisiológico/métodos , Integración de Sistemas , Adulto , Atención a la Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Telemetría
5.
Hippokratia ; 15(3): 252-7, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22435024

RESUMEN

BACKGROUND AND AIM: This study attempts to estimate the socioeconomic differences between three major alternatives for the management of upper and lower ureteral lithiasis. MATERIAL AND METHODS: Two hundred and forty patients with upper and lower ureteral lithiasis, have been studied retrospectively, divided in six equal groups of forty. These patients have been treated either by extracorporeal shockwave lithotripsy (SWL), or with ureteroscopy with semirigid ureteroscope and the use of pneumatic lithoclast, or with ureteroscopy with flexible ureteroscope and the use of Holmium YAG Laser. For cost calculation, the reimbursement fee paid by insurance to the hospital was taken into account. For the estimation of the social burden, the length of hospital stay and the number of outpatient visits have been included as countable parameters. RESULTS: The percentage of effective stone removal for upper ureter was 81.0% for SWL, 62.5% for ureteroscopy with semirigid ureteroscope and the use of pneumatic lithoclast and, 82.5% for ureteroscopy with flexible ureteroscope and the use of Holmium YAG Laser. The same percentages for lower ureter were 82.5%, 92.5% and 97.5% respectively. The cost of stone removal for both the upper and lower ureter using extracorporeal lithotripsy was significantly higher compared to the other two procedures (median cost for upper ureter 828 € vs 474.50 € and 396 € respectively, and for lower ureter 826 € vs 396 € and 271 €, p<0.001). Regarding the social aspect, SWL is mainly an outpatient procedure, requiring a short hospital stay (for upper ureter 1.63 vs 2.48 and 2.45 respectively and for lower ureter 1.35 vs 2.43 and 2.13days), but needing more and prevailing clinic visits (for upper ureter 1.43 vs 1.45 and 1 respectively and for lower ureter 1.45 vs 1.15 and 0.55 visitsgive numbers, compare), both in outpatient and in accident and emergency (A&E) department. CONCLUSION: The increase in the expenses with regard to health management indicates the necessity of cost accounting the health programs including the medical procedures as a means to improve the relation between cost and benefit.

6.
Virchows Arch ; 457(5): 619-22, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20842377

RESUMEN

BACKGROUND: Catecholamine-producing tumours are called pheochromocytomas when they are located in the adrenal gland and sympathetic paragangliomas when they are located elsewhere in the abdomen. Rarely these tumours do not produce catecholamines and even more rarely they arise in the spermatic cord. Over the past decade, systematic mutation analysis of apparently sporadic cases of pheochromocytomas and paragangliomas has elucidated the frequent presence of germ line mutations in one of five candidate genes, including RET, VHL, SDHB, SDHC, and SDHD. CLINICAL HISTORY AND METHODS: We describe a 45-year-old man with a non catecholamine-producing paraganglioma of the spermatic cord. We performed SDHB immunohistochemistry and performed mutation analysis of the SDHB, SDHC, and SDHD genes. RESULTS: There was no staining of tumour cells with SDHB immunohistochemistry, indicative of an SDH mutation. Mutation analysis demonstrated a germ line SDHD mutation (p.Val147Met). CONCLUSIONS: Systematic mutation analysis is required in paraganglioma patients for the detection of germ line mutations. This should be preceded by SDHB immunohistochemistry to limit the number of genes to be tested.


Asunto(s)
Neoplasias de los Genitales Masculinos/genética , Neoplasias de los Genitales Masculinos/patología , Mutación de Línea Germinal , Paraganglioma Extraadrenal/genética , Paraganglioma Extraadrenal/patología , Cordón Espermático/patología , Secuencia de Bases , Análisis Mutacional de ADN , Humanos , Inmunohistoquímica , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Succinato Deshidrogenasa/genética , Succinato Deshidrogenasa/metabolismo , Sistema Nervioso Simpático/patología
7.
J Evol Biol ; 23(5): 966-76, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20298442

RESUMEN

Sperm competition is important in species with reproductive strategies that involve multiple mating and prolonged sperm storage such as the simultaneously hermaphroditic land snail Cornu aspersum. Double mating trials in this species have revealed that mating order and courtship behaviour affect paternity success. We investigated the effect of behavioural and anatomical reproductive traits on paternity success from triple mating trials. Triple mating resulted in triple fertilization in 58% of the cases whereas zero paternity was observed in 16% of sperm donors. Third sperm donors achieved higher paternity followed by first and second sperm donors. Snails with a longer epiphallus, the spermatophore forming organ, sired more offspring regardless of their mating order. Genetic compatibility between sperm donor and recipient did not influence paternity success. The results of the present study identified mating order and epiphallus length, as traits affecting the outcome of sperm competition in this species.


Asunto(s)
Genitales Masculinos/anatomía & histología , Preferencia en el Apareamiento Animal/fisiología , Conducta Sexual Animal/fisiología , Caracoles/fisiología , Espermatozoides/fisiología , Animales , Pesos y Medidas Corporales , Trastornos del Desarrollo Sexual , Fertilización/fisiología , Grecia , Modelos Lineales , Masculino , Caracoles/anatomía & histología
8.
J Fish Biol ; 74(8): 1816-25, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-20735673

RESUMEN

The genetic diversity of Greek wild and farmed populations of Sparus aurata was investigated using seven microsatellite markers. Selective breeding programmes and founder effects have altered the composition of farmed populations leading to significant population differentiation between wild and cultured populations and lower allelic richness in farmed populations.


Asunto(s)
Variación Genética , Genética de Población , Repeticiones de Microsatélite , Dorada/genética , Alelos , Animales , Acuicultura , Grecia , Análisis de Secuencia de ADN
9.
Methods Inf Med ; 47(3): 229-34, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18473089

RESUMEN

OBJECTIVES: Sensor networks constitute the backbone for the construction of personalized monitoring systems. Up to now, several sensor networks have been proposed for diverse pervasive healthcare applications, which are however characterized by a significant lack of open architectures, resulting in closed, non-interoperable and difficult to extend solutions. In this context, we propose an open and reconfigurable wireless sensor network (WSN) for pervasive health monitoring, with particular emphasis in its easy extension with additional sensors and functionality by incorporating embedded intelligence mechanisms. METHODS: We consider a generic WSN architecture comprised of diverse sensor nodes (with communication and processing capabilities) and a mobile base unit (MBU) operating as the gateway between the sensors and the medical personnel, formulating this way a body area network (BAN). The primary focus of this work is on the intra-BAN data communication issues, adopting SensorML as the data representation mean, including the encoding of the monitoring patterns and the functionality of the sensor network. RESULTS: In our prototype implementation two sensor nodes are emulated; one for heart rate monitoring and the other for blood glucose observations, while the MBU corresponds to a personal digital assistant (PDA) device. Java 2 Micro Edition (J2ME) is used to implement both the sensor nodes and the MBU components. Intra-BAN wireless communication relies on the Blue-tooth protocol. Via an adaptive user interface in the MBU, health professionals may specify the monitoring parameters of the WSN and define the monitoring patterns of interest in terms of rules. CONCLUSIONS: This work constitutes an essential step towards the construction of open, extensible, inter-operable and intelligent WSNs for pervasive health monitoring.


Asunto(s)
Inteligencia Artificial , Glucemia/fisiología , Redes de Comunicación de Computadores/instrumentación , Frecuencia Cardíaca/fisiología , Monitoreo Ambulatorio/instrumentación , Telemetría/instrumentación , Grecia , Humanos , Monitoreo Ambulatorio/métodos , Proyectos Piloto , Telemetría/métodos
10.
Urol Int ; 79(1): 24-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17627163

RESUMEN

AIM: To evaluate effectiveness and safety of intracorporeal holmium:YAG (Ho:YAG) laser lithotripsy of ureteral calculi. PATIENTS AND METHODS: Between October 2003 and September 2005, 45 patients (age range 27-74, mean age 51.5 years) with 49 ureteral stones (measuring 4-28 mm in size) were treated with Ho:YAG laser lithotripsy. The locations of the stones in the ureter were: 6 in the upper third, 7 in the middle third, and 36 in the lower third. Under general anaesthesia, we used semirigid 9- to 11-Fr ureteroscopes and a flexible 7.5-Fr ureteroscope. The Ho:YAG laser had a maximum power of 1.8 J at 8 Hz, and a 365-mum flexible quartz fibre was used. One month postoperatively the patients were followed up with imaging tests. RESULTS: Stone disintegration was feasible in all cases. The mean hospital stay was 2.8 days. One month postoperatively, stone-free status was revealed in 93.3% of the cases. Only minor complications were noted in 4 patients (8.8%). No long-term complications were recorded. CONCLUSION: Ho:YAG laser lithotripsy of ureteral calculi is a feasible, safe, and effective procedure.


Asunto(s)
Litotripsia por Láser , Cálculos Ureterales/terapia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Int Urol Nephrol ; 39(3): 743-6, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17180736

RESUMEN

INTRODUCTION: Indinavir, a protease inhibitor that is commonly used to treat HIV infection, may cause crystal formation within the renal tubules when urine pH is above 3.5. Crystallization in the urine may lead to intrarenal crystal deposition and acute renal failure (ARF). AIM: To establish the beneficial urological management of acute renal failure caused by indinavir treatment of HIV/AIDS patients. PATIENTS--METHODS: Five HIV positive patients (four men, one woman) with a mean age of 32 years (range 28-36 years) were referred to our Department of Urology from an AIDS outpatient Clinic, because of the development of postrenal acute renal failure with continuously elevated creatinine and urea plasma levels after indinavir therapy. Among the initial therapeutic maneuvers, indinavir administration was interrupted for 1 week while bilateral double-J ureteral stents were inserted in all the HIV/AIDS patients, during the first 24-72 h to secure upper-tract drainage. Concurrently urine has been acidified by oral administration of the amino acid L: -methionine and oral fluid intake was increased. RESULTS: All the patients responded well to the treatment and their renal function was effortlessly restored to normal within a few days. CONCLUSION: HIV-positive patients receiving indinavir therapy might be complicated by acute renal failure, mainly due to intrarenal crystal deposition (tubules) or urolithiasis (postrenal obstruction). This adverse effect may simply manage by the discontinuation of indinavir administration, urine acidification, as well as the possible early insertion of bilateral double-J ureteral stents.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/terapia , Inhibidores de la Proteasa del VIH/efectos adversos , Seropositividad para VIH/tratamiento farmacológico , Indinavir/efectos adversos , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Lesión Renal Aguda/epidemiología , Adulto , Comorbilidad , Femenino , Inhibidores de la Proteasa del VIH/uso terapéutico , Seropositividad para VIH/epidemiología , Humanos , Indinavir/uso terapéutico , Masculino , Stents
13.
Folia Med (Plovdiv) ; 48(1): 31-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16918052

RESUMEN

OBJECTIVE: To assess the surgical technique of Mainz II urinary diversion and to discuss its simplicity, quickness of performance, short postoperative period, few postoperative complications, as well as its effectiveness allowing patients to have a very good quality of life. PATIENTS AND METHODS: Over the last six and a half years, 47 patients aged between 65 and 76 years (mean age 69.9 +/- 2.5 years) underwent radical cystectomy and Mainz II ureterosigmoidostomy for invasive bladder cancer. All patients were followed according to a standard protocol including assessment of continence, renal function and acid-base balance. RESULTS: Most of the patients retained normal renal function, complete continence and acid-base balance. There were no perioperative complications. In three patients there was urine leakage. Four patients presented with pyelonephritis and needed hospitalization. Mild hyperchloraemic acidosis was seen in nine patients. Most of them were pleased from their new quality of life. CONCLUSION: The modified Mainz II ureterosigmoidostomy is a simple, quick, easy and safe procedure to achieve urinary diversion in invasive bladder cancer resulting in a very good quality of life for patients without altering their appearance and making them capable of performing all kinds of work.


Asunto(s)
Colon Sigmoide/trasplante , Colostomía/métodos , Uréter/cirugía , Ureterostomía/métodos , Neoplasias de la Vejiga Urinaria/cirugía , Reservorios Urinarios Continentes , Anciano , Femenino , Grecia/epidemiología , Humanos , Masculino , Satisfacción del Paciente , Calidad de Vida , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/mortalidad
14.
Pediatr Nephrol ; 20(9): 1343-5, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15973527

RESUMEN

Our experiences of managing nocturnal enuresis in Greek children at our Outpatient Clinics of Pediatric Urology are described. Between March 2001 and October 2003, 142 children with primary nocturnal enuresis (93 boys and 49 girls), aged 7-18 years old (mean: 9.0+/-0.5) were included in this prospective study. Initially, behavioral conditioning therapy, using a body-worn urinary alarm, was instructed in all cases. If no improvement was recorded, 40 microg of intranasal desmopressin was administered, initially for three months. If urodynamic studies demonstrated pure detrusor instability, anticholinergics (5 mg oxybutinine or 2 mg tolterodine) were given instead. Combination medication (desmopressin and anticholinergics) was administered for coexisting diurnal enuresis, which was present in 8 children. Among the 142 children the overall response rate was 51.41%. Successful response was recorded in 16 children practicing conditioning behavioral therapy, in 47 receiving desmopressin (with or without anticholinergics), and in 10 children receiving only anticholinergics. During the follow-up period (mean: 6.2 months), no serious side effect was recorded. The use of desmopressin, and anticholinergics in specific subgroups, was found to be effective and safe for the management of nocturnal enuresis in children.


Asunto(s)
Desamino Arginina Vasopresina/administración & dosificación , Enuresis/tratamiento farmacológico , Fármacos Renales/administración & dosificación , Administración Intranasal , Adolescente , Terapia Conductista/métodos , Niño , Antagonistas Colinérgicos/uso terapéutico , Enuresis/terapia , Femenino , Grecia , Humanos , Masculino , Estudios Prospectivos , Fármacos Renales/uso terapéutico , Resultado del Tratamiento
15.
Folia Med (Plovdiv) ; 47(2): 24-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16544846

RESUMEN

AIM: We present our experience in the treatment of enuresis at the Pediatric Urology Outpatient Office over a period of four years. We report pertinent epidemiological data, diagnostic workup, as well as routine treatment protocol. MATERIAL AND METHODS: Between April 1998 and May 2002, 142 healthy children, aged between 6.5 and 18 years (mean: 9 +/- 0.5 years), were referred to us for bedwetting. Ninety three of them were boys and 49--girls. Eight of them had also concurrent daytime enuresis. According to our protocol, the type of enuresis was identified (primary or secondary) and then we administered the respective treatment. Sixteen children underwent behavioural therapy only. Fifteen children with detrusor instability received oxybutinine or tolterodine. Twenty children with diurnal and nocturnal enuresis were given desmopressin and oxybutinine or desmopressin and tolterodine. The remaining 91 children received monotherapy with desmopressin (individualized dose). The initial follow up ranged from 3 to 6 months. RESULTS: Out of 111 children receiving desmopressin, 66 stopped wetting, but 28 relapsed in two weeks and treatment continued for 3 more months. Nine children became dry. In the other groups there was almost complete response to treatment. CONCLUSION: Enuresis continues to be a suppressed problem for both children and parents; however, effective treatment is possible.


Asunto(s)
Enuresis/diagnóstico , Enuresis/terapia , Adolescente , Fármacos Antidiuréticos/uso terapéutico , Terapia Conductista , Compuestos de Bencidrilo/uso terapéutico , Distribución de Chi-Cuadrado , Niño , Terapia Combinada , Cresoles/uso terapéutico , Desamino Arginina Vasopresina/uso terapéutico , Quimioterapia Combinada , Enuresis/epidemiología , Femenino , Grecia/epidemiología , Humanos , Masculino , Ácidos Mandélicos/uso terapéutico , Fenilpropanolamina/uso terapéutico , Tartrato de Tolterodina , Resultado del Tratamiento
16.
Mol Ecol ; 13(6): 1377-90, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15140084

RESUMEN

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 (F(ST) = 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 (pi = 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.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Genética de Población , Nephropidae/genética , Filogenia , Análisis de Varianza , Animales , Océano Atlántico , Análisis por Conglomerados , Cartilla de ADN , Demografía , Geografía , Haplotipos/genética , Polimorfismo de Longitud del Fragmento de Restricción , Dinámica Poblacional
18.
Mol Ecol ; 11(6): 1039-55, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12030981

RESUMEN

The genetic structure of Silurus glanis (Europe's largest freshwater fish species) across most of its natural distribution was investigated using 10 microsatellite loci. The revealed levels of genetic diversity were much higher than previous allozyme and restriction fragment length polymorphism mitochondrial DNA analyses had shown; relative levels of variability among populations were however, in good agreement with the previous studies. Populations from large basins (Volga and Danube rivers) were the most polymorphic, while samples from the smaller Greek rivers, which are more prone to genetic bottleneck, exhibited the lowest levels of genetic diversity. Microsatellite multilocus genotyping permitted the assignment of individual fish to their population of origin with a score as high as 98.3%. Despite the great genetic differentiation of S. glanis populations, no consistent pattern of geographical structuring was revealed, in contrast to previous studies of European freshwater fish species. A model of isolation by distance seems more probable and a hypothesis of recent dispersion from only one glacial refugium is proposed. The discovery of the highest levels of microsatellite and mitochondrial diversity in the Volga sample and the presence of river connections, during the Pleistocene, between this area and all major areas of the present catfish distribution, place this refugium around the Ponto-Caspian region. Combining these data with those from previous studies, a number of markers are now available to monitor wild and hatchery populations even at the individual level.


Asunto(s)
Bagres/genética , Variación Genética , Repeticiones de Microsatélite , Filogenia , Animales , Bagres/clasificación , ADN Mitocondrial/análisis , ADN Mitocondrial/genética , Ecología , Europa (Continente) , Frecuencia de los Genes , Heterogeneidad Genética , Genética de Población , Genotipo , Geografía , Desequilibrio de Ligamiento , Polimorfismo Genético , Estadística como Asunto
19.
Heredity (Edinb) ; 82 (Pt 5): 503-9, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10383670

RESUMEN

Mitochondrial DNA diversity of seven Silurus glanis populations (six from Greece and one from the Danube Delta) and three populations of the endemic Greek Silurus aristotelis was investigated. RFLP analysis of four regions of mitochondrial DNA (cytochrome b, D-loop, ND-5/6) amplified by PCR was used. Ten and nine haplotypes were found in S. glanis and S. aristotelis, respectively. No haplotype was shared between the two species. Significant geographical substructuring was observed in the distribution of haplotypes, with most populations possessing private haplotypes. These haplotypes can serve as genetic 'tags' and therefore warrant protection. Haplotype diversity was very low for all Greek S. glanis populations, possibly because the small size and large annual fluctuations of Greek inland waters do not support large fish populations. Nucleotide divergence was in the range of 0.00-0.52% among S. glanis populations, and 0. 00-0.11% among S. aristotelis populations. Historical factors such as glaciations could account for these low values. The value of 6. 75% sequence divergence of the two species refutes the classification of the two species in different genera, as proposed by some authors. This study constitutes the first attempt, based on mitochondrial molecular data, to address the complicated evolutionary history of the two species which belong to the widely distributed and economically important Siluridae family.

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