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1.
Akush Ginekol (Sofiia) ; 55 Suppl 1 Pt 2: 15-9, 2016.
Artículo en Búlgaro | MEDLINE | ID: mdl-27509663

RESUMEN

ABSTRACT OBJECTIVE: To present a case of macrocystic type cystic adenomatoid malformation of the lung (CCAM) treated with thoraco-amniotic shunt and to review the published data to evaluate the efficiency of thoraco-amniotic shunts for drainage of (CCAM). MATERIALS AND METHODS: This wass case reported of a fetus with a large thoracic cyst, major mediastinal shift and polyhidramnion treated with thoraco-amniotic shunting. We identified 8 cases diagnosed with CCAM and only one case met the criteria for fetal surgery. Thoracoamniotic shunting was successfully performed under local anesthesia and ultrasound control with operating time of 35 minutes. Medline was searched to identify cases of CCAM treated by thoraco-amniotic shunting. RESULTS: Fetal therapy forlung lesion was successfully performed at 30 weeks of gestation with CCAM volume ratio > 1.6 January, 2015 and amniodrenage after the procedure was carried out. The pregnancy has progressed uneventfully and planned Cesarean section was performed at 38 weeks of gestation. The optimal management of such case was performed for the first time in Bulgaria, which required an experienced interdisciplinary team. The newborn underwent resection of the lesion with no growth or neurodevelopment delay. The literature search identified cases with CCAM treated with thoraco-amniotic shunting between 1987 and 2016 and the the survival rate of non-hydropic fetuses that underwent treatment was 88%. CONCLUSIONS: Thoraco-amniotic shunting for macrocystic type CCAM is associated reduced risk of fetal intrauterine death and is also likely to be beneficial for the following major postnatal surgery


Asunto(s)
Malformación Adenomatoide Quística Congénita del Pulmón/diagnóstico , Malformación Adenomatoide Quística Congénita del Pulmón/terapia , Terapias Fetales/métodos , Pulmón/anomalías , Cesárea , Femenino , Humanos , Recién Nacido , Embarazo , Ultrasonografía Prenatal
2.
Mol Ecol ; 23(18): 4603-16, 2014 09.
Artículo en Inglés | MEDLINE | ID: mdl-25113130

RESUMEN

Parallel patterns of adaptive divergence and speciation are cited as powerful evidence for the role of selection driving these processes. However, it is often not clear whether parallel phenotypic divergence is underlain by parallel genetic changes. Here, we asked about the genetic basis of parallel divergence in the marine snail Littorina saxatilis, which has repeatedly evolved coexisting ecotypes adapted to either crab predation or wave action. We sequenced the transcriptome of snails of both ecotypes from three distant geographical locations (Spain, Sweden and United Kingdom) and mapped the reads to the L. saxatilis reference genome. We identified genomic regions potentially under divergent selection between ecotypes within each country, using an outlier approach based on F(ST) values calculated per locus. In line with previous studies indicating that gene reuse is generally common, we expected to find extensive sharing of outlier loci due to recent shared ancestry and gene flow between at least two of the locations in our study system. Contrary to our expectations, we found that most outliers were country specific, suggesting that much of the genetic basis of divergence is not shared among locations. However, we did find that more outliers were shared than expected by chance and that differentiation of shared outliers is often generated by the same SNPs. We discuss two mechanisms potentially explaining the limited amount of sharing we observed. First, a polygenic basis of divergent traits might allow for multiple distinct molecular mechanisms generating the same phenotypic patterns. Second, additional, location-specific axes of selection that we did not focus on in this study may produce distinct patterns of genetic divergence within each site.


Asunto(s)
Ecotipo , Genética de Población , Selección Genética , Caracoles/genética , Adaptación Biológica/genética , Animales , Fenotipo , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , España , Suecia , Transcriptoma , Reino Unido
3.
Gene ; 824: 146389, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35257790

RESUMEN

Mechanisms of reproductive isolation between closely related sympatric species are of high evolutionary significance as they may function as initial drivers of speciation and protect species integrity afterwards. Proteins involved in the establishment of reproductive barriers often evolve fast and may be key players in cessation of gene flow between the incipient species. The five Atlantic Littorina (Neritrema) species represent a notable example of recent radiation. The geographic ranges of these young species largely overlap and the mechanisms of reproductive isolation are poorly understood. In this study, we performed a detailed analysis of the reproductive protein LOSP, previously identified in Littorina. We showed that this protein is evolutionary young and taxonomically restricted to the genus Littorina. It has high sequence variation both within and between Littorina species, which is compatible with its presumable role in the reproductive isolation. The strongest differences in the LOSP structure were detected between Littorina subgenera with distinctive repetitive motifs present exclusively in the Neritrema species, but not in L. littorea. Moreover, the sequence of these repetitive structural elements demonstrates a high homology with genetic elements of bacteria, identified as components of Littorina associated microbiomes. We suggest that these elements were acquired from a symbiotic bacterial donor via horizontal genetic transfer (HGT), which is indirectly confirmed by the presence of multiple transposable elements in the LOSP flanking and intronic regions. Furthermore, we hypothesize that this HGT-driven evolutionary innovation promoted LOSP function in reproductive isolation, which might be one of the factors determining the intensive cladogenesis in the Littorina (Neritrema) lineage in contrast to the anagenesis in the L. littorea clade.


Asunto(s)
Microbiota , Caracoles , Animales , Bacterias , Flujo Génico , Especiación Genética , Aislamiento Reproductivo , Caracoles/genética
4.
Sci Rep ; 11(1): 23120, 2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34848799

RESUMEN

The pathophysiology of osteoarthritis (OA) includes the destruction of subchondral bone tissue and inflammation of the synovium. Thus, an effective disease-modifying treatment should act on both of these pathogenetic components. It is known that cSrc kinase is involved in bone and cartilage remodeling, and SYK kinase is associated with the inflammatory component. Thus the aim of this study was to characterize the mechanism of action and efficacy of a small molecule multikinase inhibitor MT-SYK-03 targeting SYK and cSrc kinases among others in different in vitro and in vivo arthritis models. The selectivity of MT-SYK-03 kinase inhibition was assayed on a panel of 341 kinases. The compound was evaluated in a set of in vitro models of OA and in vivo OA and RA models: surgically-induced arthritis (SIA), monosodium iodoacetate-induced arthritis (MIA), collagen-induced arthritis (CIA), adjuvant-induced arthritis (AIA). MT-SYK-03 inhibited cSrc and SYK with IC50 of 14.2 and 23 nM respectively. Only five kinases were inhibited > 90% at 500 nM of MT-SYK-03. In in vitro OA models MT-SYK-03 reduced hypertrophic changes of chondrocytes, bone resorption, and inhibited SYK-mediated inflammatory signaling. MT-SYK-03 showed preferential distribution to joint and bone tissue (in rats) and revealed disease-modifying activity in vivo by halving the depth of cartilage erosion in rat SIA model, and increasing the pain threshold in rat MIA model. Chondroprotective and antiresorptive effects were shown in a monotherapy regime and in combination with methotrexate (MTX) in murine and rat CIA models; an immune-mediated inflammation in rat AIA model was decreased. The obtained preclinical data support inhibition of cSrc and SYK as a viable strategy for disease-modifying treatment of OA. A Phase 2 clinical study of MT-SYK-03 is to be started.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/enzimología , Huesos/efectos de los fármacos , Proteína Tirosina Quinasa CSK/antagonistas & inhibidores , Cartílago/efectos de los fármacos , Osteoartritis/tratamiento farmacológico , Osteoartritis/enzimología , Quinasa Syk/antagonistas & inhibidores , Animales , Artritis Experimental/patología , Resorción Ósea/patología , Condrocitos/patología , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/farmacología , Humanos , Inflamación , Concentración 50 Inhibidora , Ácido Yodoacético/farmacología , Receptores de Lipopolisacáridos/biosíntesis , Masculino , Ratones , Monocitos/citología , Sustancias Protectoras/farmacología , Conejos , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Membrana Sinovial/patología
5.
Mol Ecol ; 18(19): 4006-23, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19754510

RESUMEN

Formation of partially reproductively isolated ecotypes in the rough periwinkle, Littorina saxatilis, may be a case of incipient nonallopatric ecological speciation. To better understand the dynamics of ecotype formation, its timescale, driving forces and evolutionary consequences, we developed a spatially explicit, individual-based model incorporating relevant ecological, spatial and mate selection data for Swedish L. saxatilis. We explore the impact of bounded hybrid superiority, ecological scenarios and mate selection systems on ecotype formation, gene flow and the evolution of prezygotic isolation. Our model shows that ecotypes are expected to form rapidly in parapatry under conditions applicable to Swedish L. saxatilis and may proceed to speciation. However, evolution of nonrandom mating had complex behaviour. Ecotype evolution was inhibited by pre-existing mating preferences, but facilitated by the evolution of novel preferences. While in many scenarios positive assortative mating reduced gene flow between ecotypes, in others negative assortative mating arose, preferences were lost after ecotype formation, preferences were confined to one ecotype or the ancestral ecotype became extinct through sexual selection. Bounded hybrid superiority (as observed in nature) enhanced ecotype formation but increased gene flow. Our results highlight that ecotype formation and speciation are distinct processes: factors that contribute to ecotype formation can be detrimental to speciation and vice versa. The complex interactions observed between local adaptation and nonrandom mating imply that generalization from data is unreliable without quantitative theory for speciation.


Asunto(s)
Flujo Génico , Especiación Genética , Modelos Genéticos , Caracoles/genética , Animales , Ecología , Genética de Población , Reproducción/genética , Conducta Sexual Animal , Suecia
6.
J Evol Biol ; 22(10): 2000-11, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19678865

RESUMEN

Some mitochondrial introgression is common between closely related species, but distinct species rarely show substantial introgression in their entire distribution range. In this study, however, we report a complete lack of mitochondrial divergence between two sympatric species of flat periwinkles (Littorina fabalis and Littorina obtusata) which, based on previous allozyme studies, diverged approximately 1 Ma. We re-examined their species status using both morphology (morphometric analysis) and neutral genetic markers (microsatellites) and our results confirmed that these species are well separated. Despite this, the two species shared all common cytochrome-b haplotypes throughout their NE Atlantic distribution and no deep split between typical L. fabalis and L. obtusata haplotypes could be found. We suggest that incomplete lineage sorting explains most of the lack of mitochondrial divergence between these species. However, coalescent-based analyses and the sympatric sharing of unique haplotypes suggest that introgressive hybridization also has occurred.


Asunto(s)
Biología Marina , Mitocondrias/genética , Vinca/genética , Animales , Secuencia de Bases , Citocromos b/genética , Cartilla de ADN , Haplotipos , Repeticiones de Microsatélite , Especificidad de la Especie , Vinca/clasificación
7.
Eur J Paediatr Neurol ; 22(4): 674-681, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29656927

RESUMEN

Pontocerebellar hypoplasia type 1 (PCH1) is a major cause of non-5q spinal muscular atrophy (SMA). We screened 128 SMN1-negative SMA patients from Bulgaria for a frequent mutation -p.G31A in EXOSC3, and performed a literature review of all genetically verified PCH1 cases. Homozygous p.G31A/EXOSC3 mutation was identified in 14 Roma patients, representing three fourths of all our SMN1-negative Roma SMA cases. The phenotype of the p.G31A/EXOSC3 homozygotes was compared to the clinical presentation of all reported to date genetically verified PCH1 cases. Signs of antenatal onset of disease present at birth were common in all PCH1 sub-types except in the homozygous p.D132A/EXOSC3 patients. The PCH1sub-types with early death (between ages 1 day and 17 months), seen in patients with p.G31A/EXOSC3 or SLC25A46 mutations have a SMA type 1-like clinical presentation but with global developmental delay, visual and hearing impairment, with or without microcephaly, nystagmus and optic atrophy. Mutations with milder presentation (homozygous p.D132A/EXOSC3 or VRK1) may display additionally signs of upper motor neuron impairment, dystonia or ataxia and die at age between 5 and 18 years. Other EXOSC3 mutations and EXOSC8 cases are intermediate - SMA type 1-like presentation, spasticity (mostly in EXOSC8) and death between 3 months and 5 years. There is no correlation between neurological onset and duration of life. We add marble-like skin and congenital laryngeal stridor as features of PCH1. We show that imaging signs of cerebellar and pontine hypoplasia may be missing early in infancy. EMG signs of anterior horn neuronopathy may be missing in PCH1 patients with SLC25A46 mutations. Thus, there is considerable phenotypic variability in PCH1, with some cases being more SMA-like, than PCH-like. Detailed clinical evaluation and ethnicity background may guide genetic testing and subsequent genetic counseling.


Asunto(s)
Atrofias Olivopontocerebelosas/diagnóstico , Atrofias Olivopontocerebelosas/genética , Atrofias Musculares Espinales de la Infancia/genética , Adolescente , Bulgaria , Niño , Preescolar , Complejo Multienzimático de Ribonucleasas del Exosoma/genética , Femenino , Estudios de Asociación Genética , Homocigoto , Humanos , Masculino , Mutación , Atrofias Olivopontocerebelosas/patología , Fenotipo , Proteínas de Unión al ARN/genética , Romaní/genética
9.
Parasitol Int ; 55(4): 249-60, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16901748

RESUMEN

Fascioliasis is an important human and animal disease caused by Fasciola hepatica and Fasciola gigantica. In Iran, the distribution of these two species overlaps in most areas, including the northern human endemic province of Gilan where both fasciolids are simultaneously found in individual cattle and buffaloes. A phenotypic study of fasciolid adult flukes from naturally infected bovines from Gilan was carried out by means of an exhaustive morphometric analysis using traditional microscopic measurements and an allometric model. The Iranian fasciolids were compared to F. hepatica and F. gigantica standard populations, i.e. from geographical areas where both species do not co-exist (Bolivia and Burkina Faso, respectively). Although morphometric values somewhat overlapped, there were clear differences in allometric growth. The allometric function was adjusted to 25 pairs of variables. Results obtained revealed that Iranian F. hepatica-like specimens are larger than the F. hepatica standard and Iranian F. gigantica-like specimens are longer and narrower than the F. gigantica standard, but with smaller body area. Measurements which permit a specific differentiation in allopatric populations (distance between ventral sucker and posterior end of the body; ratio between body length and body width) overlap in the specimens from Gilan, thus proving the presence of intermediate forms. When compared to the standard populations, the different Iranian fasciolid morphs show greater differences in F. gigantica-like specimens than in F. hepatica-like specimens. This study shows that simple, traditional microscopic measurements may be sufficient for the morphometric characterisation of fasciolids, even in areas where intermediate forms are present.


Asunto(s)
Búfalos/parasitología , Enfermedades de los Bovinos/parasitología , Enfermedades Endémicas/veterinaria , Fasciola/anatomía & histología , Fasciola/clasificación , Fascioliasis/veterinaria , Animales , Bolivia , Burkina Faso , Bovinos , Enfermedades de los Bovinos/epidemiología , Clasificación/métodos , Fasciola hepatica/anatomía & histología , Fasciola hepatica/clasificación , Fascioliasis/epidemiología , Fascioliasis/parasitología , Irán/epidemiología , Hígado/parasitología , Modelos Logísticos , Fenotipo , Especificidad de la Especie , Factores de Tiempo
10.
Vet Parasitol ; 102(1-2): 85-100, 2001 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-11705655

RESUMEN

The highest prevalences and intensities of human fasciolosis by Fasciola hepatica are found in the northern Bolivian Altiplano, where sheep and cattle are the main reservoir host species and pigs and donkeys the secondary ones. Morphometric comparisons of many linear measurements, areas and ratios of F. hepatica adults (from sheep, cattle and pigs) and eggs (from sheep, cattle, pigs and donkeys) in natural liver fluke populations of the Bolivian Altiplano, as well as of F. hepatica adults and eggs experimentally obtained in Wistar rats infected with Altiplanic sheep, cattle and pig isolates, were made using computer image analysis and an allometric model. Although morphometric values of adult flukes from natural populations of sheep, cattle, and pigs showed great overlap, there were clear differences in allometric growth. The allometries analyzed were: body area (BA) versus body length (BL), BA versus body width (BW), BA versus perimeter (Pe), BA versus distance between posterior end of body and ventral sucker (P-VS), BL versus BW, BL versus Pe, and BL versus P-VS. These allometries show a good fit in the seven pairs of variables in all the populations examined. Comparative statistical analysis of the allometries shows that fluke adult populations from sheep, cattle and pigs significantly differ in BL versus BW and BL versus P-VS functions. Statistical analysis of F. hepatica egg size shows characteristic morphometric traits in each definitive host species. In experimentally infected rats, fluke adult allometry and egg morphometry do not vary depending on the Altiplanic definitive host species isolate. Our study reveals that the definitive host species decisively influences the size of F. hepatica adults and eggs, and these influences do not persist in a rodent definitive host model.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Fasciola hepatica/crecimiento & desarrollo , Fascioliasis/veterinaria , Enfermedades de las Ovejas/parasitología , Enfermedades de los Porcinos/parasitología , Animales , Bolivia , Bovinos/parasitología , Reservorios de Enfermedades , Fasciola hepatica/fisiología , Fascioliasis/parasitología , Heces/parasitología , Interacciones Huésped-Parásitos , Óvulo/crecimiento & desarrollo , Óvulo/fisiología , Recuento de Huevos de Parásitos/veterinaria , Ratas , Ratas Wistar , Ovinos , Especificidad de la Especie , Porcinos
11.
Mol Biol (Mosk) ; 10(5): 1175-82, 1976.
Artículo en Ruso | MEDLINE | ID: mdl-1053077

RESUMEN

By means of high sensitive spectrofluorometer the fluorescence spectra have been measured of normal chloroplasts and those with blocked photosystem 2 activity due to photoinhibition or treatment with 0.6 M tris-buffer. At room temperature fluorescence spectra of inactivated chloroplasts are similar to the spectrum of normal chloroplasts measured at low light intensity. Under excitation by intense light a decrease of intensity at 685 nm is appeared (about 3-4 times) in the fluorescence spectra of inactivated chloroplasts as compared to the spectrum of normal chloroplasts. The sharp intensity decrease of maxima at 685 and 695 nm (3-4 times) and small decrease at 680 and 730 nm (by 30-50%) are observed in low temperature fluorescence spectra of inactivated chloroplasts. Thus, the damage of photosystem 2 reaction centres is not accompanied by the preferential decrease of the only fluorescence band. The similarity of fluorescence difference spectra of chloroplasts distinguished by the state of photosystem 2 reaction centre, and the complex structure of difference spectra indicate that the variable fluorescence of chloroplasts during the induction is due to the emission of bulk chlorophyll alpha of the photosystem 2.


Asunto(s)
Cloroplastos/metabolismo , Fotosíntesis , Cinética , Espectrometría de Fluorescencia
12.
Kardiologiia ; 24(12): 33-6, 1984 Dec.
Artículo en Ruso | MEDLINE | ID: mdl-6521223

RESUMEN

Fifty-three patients with brady-cardia were examined prior to and 1 year after the implantation of the cardiostimulator. It was found that the bicycle ergometric test was not contraindicated in examining the function of the respiration and circulation in patients with stable forms of bradyarrhythmia. Three types of the body's response to exercise were identified. It was shown that in patients with the third type of response the compensatory possibilities of the respiratory and cardiovascular systems were at the breaking point. The authors believe that electrocardiostimulation in them is of a doubtful value in terms of improving the quality of life and restoring the capacity for work. Implantation of cardiostimulators in such patients is mostly necessary in the presence of Morgagni-Edems-Stokes attacks.


Asunto(s)
Bradicardia/terapia , Presión Sanguínea , Gasto Cardíaco , Estimulación Cardíaca Artificial , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Consumo de Oxígeno
13.
Vopr Med Khim ; 21(3): 290-5, 1975.
Artículo en Ruso | MEDLINE | ID: mdl-1210106

RESUMEN

Distinct impairments in collagen metabolism were observed in infectious (rheumatoid) polyarthritis. The impairements were manifested as increased excretion of hydroxyproline with urine and increased content of protein bound hydroxyproline in blood plasma and synovial fluid; the impairements increased with an increased in severity and abundance of pathological process in connective tissue. After successful treatment of patients (surgical operation, combined with complex antirheumatic treatment) content of the collagen metabolites was decreased in biological fluids; this decrease was not observed if the inflammatory process in the connective tissue was present.


Asunto(s)
Artritis Infecciosa/metabolismo , Artritis Reumatoide/metabolismo , Colágeno/metabolismo , Tejido Conectivo/metabolismo , Humanos , Hidroxiprolina/metabolismo
14.
Mol Ecol Resour ; 10(2): 282-91, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21565023

RESUMEN

We describe an efficient algorithm for determining exactly the minimum number of sires consistent with the multi-locus genotypes of a mother and her progeny. We consider cases where a simple exhaustive search through all possible sets of sires is impossible in practice because it would take too long to complete. Our algorithm for solving this combinatorial optimization problem avoids visiting large parts of search space that would not result in a solution with fewer sires. This improvement is of particular importance when the number of allelic types in the progeny array is large and when the minimum number of sires is expected to be large. Precisely in such cases, it is important to know the minimum number of sires: this number gives an exact bound on the most likely number of sires estimated by a random search algorithm in a parameter region where it may be difficult to determine whether it has converged. We apply our algorithm to data from the marine snail, Littorina saxatilis.

18.
Mol Ecol ; 15(13): 4021-31, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17054500

RESUMEN

The evolution of reproductive isolation in the presence of gene flow is supported by theoretical models but rarely by data. Empirical support might be gained from studies of parallel hybrid zones between interbreeding taxa. We analysed gene flow over two hybrid zones separating ecotypes of Littorina saxatilis to test the expectation that neutral genetic markers will show site-specific differences if barriers have evolved in situ. Distinct ecotypes found in contrasting shore habitats are separated by divergent selection and poor dispersal, but hybrid zones appear between them. Swedish islands formed by postglacial uplift 5000 years ago provide opportunities to assess genetic structure in a recently evolved system. Each island houses a discrete population containing subpopulations of different ecotypes. Hybrid zones between ecotypes may be a product of ecological divergence occurring on each island or a consequence of secondary overlap of ecotypes of allopatric origin that have spread among the islands. We used six microsatellite loci to assess gene flow and genetic profiles of hybrid zones on two islands. We found reduced gene flow over both hybrid zones, indicating the presence of local reproductive barriers between ecotypes. Nevertheless, subpopulations of different ecotypes from the same island were genetically more similar to each other than were subpopulations of the same ecotype from different islands. Moreover, neutral genetic traits separating the two ecotypes across hybrid zones were site-specific. This supports a scenario of in situ origin of ecotypes by ecological divergence and nonallopatric evolution of reproductive barriers.


Asunto(s)
Evolución Biológica , Quimera/genética , Genética de Población , Reproducción/genética , Caracoles/genética , Animales , Geografía , Repeticiones de Microsatélite
19.
Parasitol Res ; 99(4): 368-78, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16568331

RESUMEN

The quantification of the different sizes and shapes of Fasciola hepatica and Fasciola gigantica from bovines has been achieved for the first time in natural allopatric populations. Linear measurements, areas and ratios of gravid adults and eggs of F. hepatica (from France and Spain) and F. gigantica (from Burkina Faso) were analysed using a computer image analysis system and an allometric model: (y2m - y2)/y2 = c[(y1m - y1)/y1](b), where y1 = body area or body length, y2 = one of the measurements analysed, y1m, y2m = maximum values towards which y1 and y2, respectively, tend and c, b = constants. All the measurements overlap in the two fasciolids, apart from the distance between the ventral sucker and the posterior end of the body, body roundness and body length/body width ratio. The results obtained may be useful in Fasciola species identification in countries where both species coexist.


Asunto(s)
Fasciola hepatica/anatomía & histología , Fascioliasis/veterinaria , Procesamiento de Imagen Asistido por Computador/métodos , Enfermedades Parasitarias en Animales/parasitología , África , Animales , Bovinos , Ambiente , Europa (Continente) , Fascioliasis/parasitología , Fenotipo , Aislamiento Social , Especificidad de la Especie
20.
Parasitology ; 133(Pt 4): 453-63, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16817992

RESUMEN

Fascioliasis pathogenesis depends on fluke burden. In human hyperendemic zones, individual infection intensities reach very high levels and the majority of infected subjects should be in the advanced chronic phase. The rat model offers a useful approach for pathological research in the advanced chronic period. The influence of infection intensity per rat on fluke development, pre-patent period and egg shedding (eggs/g faeces/worm) was analysed in 3 groups (I: 1-3 worms/rat; II: 4-6; III: 7-9). Ontogenetic trajectories of fluke body measures followed a logistic model. Results showed that when the burden increases, the maximum values of fluke measures decrease. The crowding effect is manifest when fluke measures approximate their maximums in the advanced chronic stage. The pre-patent period and egg production decrease when the burden increases. This means that measurements of eggs per gramme of faeces tend to underestimate the fluke burden. The present study demonstrates how to quantify the fascioliasis experimental rat model crowding effect on adult growth, pre-patent period and egg production. This quantification may be of great interest in epidemiological studies and in experimental research on the in vivo actions of different anthelminthic drugs and vaccines, pathology, immunology and resistance studies.


Asunto(s)
Fasciola hepatica/fisiología , Fascioliasis/parasitología , Modelos Biológicos , Animales , Bolivia , Enfermedad Crónica , Fasciola hepatica/crecimiento & desarrollo , Fasciola hepatica/patogenicidad , Heces/parasitología , Interacciones Huésped-Parásitos , Humanos , Modelos Logísticos , Masculino , Recuento de Huevos de Parásitos , Densidad de Población , Distribución Aleatoria , Ratas , Ratas Wistar , Caracoles/parasitología , Factores de Tiempo
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