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1.
Rev. biol. trop ; Rev. biol. trop;66(4): 1614-1628, oct.-dic. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1003351

RESUMEN

Abstract Fish-eating in bats evolved independently in Myotis vivesi (Vespertillionidae) and Noctilio leporinus (Noctilionidae). We compared cranial morphological characters and bite force between these species to test the existence of evolutionary parallelism in piscivory. We collected cranial distances of M. vivesi, two related insectivorous bats (M. velifer and M. keaysi), two facultatively piscivorous bats (M. daubentonii and M. capaccinii), and N. leporinus. We analyzed morphometric data applying multivariate methods to test for differences among the six species. We also measured bite force in M. vivesi and evaluated if this value was well predicted by its cranial size. Both piscivorous species were morphologically different from the facultatively piscivorous and insectivorous species, and skull size had a significant contribution to this difference. However, we did not find morphological and functional similarities that could be interpreted as parallelisms between M. vivesi and N. leporinus. These two piscivorous species differed significantly in cranial measurements and in bite force. Bite force measured for M. vivesi was well predicted by skull size. Piscivory in M. vivesi might be associated to the existence of a vertically displaced temporal muscle and an increase in gape angle that allows a moderate bite force to process food.(AU)


Resumen La alimentación por peces en murciélagos evolucionó independientemente en Myotis vivesi (Vespertilionidae) y Noctilio leporinus (Phyllostomidae). En este estudio se compararon características craneales morfológicas y fuerza de mordida entre estas especies, para probar la existencia de paralelismo evolucionario en piscivoría. Se recolectaron distancias craneales en M. vivesi, dos parientes insectívoros (M. velifer y M. keaysi), dos murciélagos piscívoros facultativos (M. daubentonii y M. capaccinii), y N. leporinus. Se analizaron datos morfométricos aplicando múltiples métodos para probar las diferencias entre las seis especies. Se midió la fuerza de mordida en M. vivesi y se evalúo si puede ser predicha por el tamaño del cráneo. Las especies piscívoras fueron morfológicamente diferentes de las facultativamente piscívoras y las insectívoras, el tamaño del cráneo tuvo una contribución significativa en esta diferencia. Sin embargo, no encontramos semejanzas morfológicas y funcionales que puedan ser interpretadas como paralelismos entre M. vivesi y N. leporinus. Estas dos especies piscívoras difieren significativamente en medidas craneales y fuerza de mordida. La fuerza de mordida en M. vivesi fue efectivamente predicha por el tamaño de cráneo. La piscivoría en M. vivesi puede estar asociada con la existencia de un músculo temporal verticalmente desplazado y el incremento en el ángulo de apertura mandibular que permite moderar la fuerza de mordida para procesar el alimento.(AU)


Asunto(s)
Fuerza de la Mordida , Quirópteros , Explotaciones Pesqueras , Mandíbula
2.
J Parasitol ; 104(5): 465-472, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30019985

RESUMEN

Serological tests are needed to estimate the prevalence of Taenia solium cysticercosis in endemic rural areas. The predictive value of serum antibody levels to diagnose porcine cysticercosis and human neurocysticercosis (NC) was herein assessed by ELISA using serum samples from 247 backyard pigs (141 without cysticercosis and 106 with cysticercosis) and 183 human subjects (116 non-NC subjects and 67 NC patients) in central Mexico diagnosed by necropsy and computed tomography, respectively. A sensitivity of 77.3 and 92.5% and a specificity of 88.6 and 100% were found to diagnose porcine and human cysticercosis, respectively. The prevalence of porcine and human cysticercosis in the state of Morelos was estimated by ELISA. Anti-cysticercal antibodies were found in 8.4 and 19.02% of assayed sera from 1,811 humans and 804 pigs, respectively. Marginalization and living in the eastern region were risk factors for humans, whereas free-roaming, medium marginalization levels and living in Sierra de Huautla were risk factors for pigs. These results clearly evidence the persistence of cysticercosis transmission and neurocysticercosis in a region neighboring Mexico City, pointing out the need to apply effective measures already available for its control.


Asunto(s)
Cisticercosis/veterinaria , Neurocisticercosis/epidemiología , Enfermedades de los Porcinos/epidemiología , Taenia solium/inmunología , Adolescente , Adulto , Animales , Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/inmunología , Niño , Preescolar , Cisticercosis/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Masculino , México/epidemiología , Persona de Mediana Edad , Conejos , Sensibilidad y Especificidad , Estudios Seroepidemiológicos , Porcinos , Tomografía Computarizada por Rayos X , Adulto Joven
3.
Vet Parasitol ; 176(1): 53-8, 2011 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21251758

RESUMEN

This paper provides macroscopic and histological evidence on the statistically significant protective effects of S3Pvac-phage vaccination against porcine cysticercosis and hydatidosis. The study included 391 rustically bred pigs (187 vaccinated and 204 controls). Vaccination significantly reduced the prevalence of cysticercosis by 61.7%. Vaccination also significantly reduced by 56.1% the prevalence of hydatidosis caused by Echinococcus granulosus in pigs. The presence of the vaccine epitopes in both cestodes is probably involved in the cross-protection observed. Increased inflammation was found in 5% of cysticerci recovered from controls, versus 24% from vaccinated pigs (P<0.01). Hydatid cysts were non-inflammatory in either group. Vaccination was effective to prevent one single disease, but it failed to prevent the simultaneous infections with both parasites in a same pig. The widening of the S3Pvac-phage vaccine protective repertoire to include hydatidosis is a convenient feature that should reduce the prevalence of two frequent zoonoses that affect rustic porcine breading with a single action. Thus, the costs of two different vaccination programs would be reduced to a single one with significant reduction in both zoonoses.


Asunto(s)
Cisticercosis/veterinaria , Equinococosis/veterinaria , Proteínas del Helminto/inmunología , Enfermedades de los Porcinos/prevención & control , Vacunas/inmunología , Animales , Cisticercosis/prevención & control , Equinococosis/prevención & control , Proteínas del Helminto/genética , Proteínas Recombinantes , Porcinos , Enfermedades de los Porcinos/parasitología
4.
Univ. psychol ; 9(2): 371-380, mayo 2010. ilus, tab
Artículo en Español | LILACS | ID: lil-575058

RESUMEN

El objetivo de este estudio, es comparar la prevalencia de determinadas conductas violentas en los mismos niveles educativos durante dos estudios transversales: el primero, realizado en el curso académico 2004-2005, y el segundo, tres años más tarde, durante el periodo 2007-2008. Para ello, se ha analizado una muestra total de 1.475 sujetos de edades comprendidas entre los 14 y 16 años. Los resultados muestran, que se produce un descenso significativo en la prevalencia de prácticamente todas las conductas violentas analizadas, tales como: insultos, peleas, etc., durante los años académicos mencionados anteriormente. Por otra parte, las mujeres son las que más sufren la agresión verbal indirecta y, por el contrario, los hombres son los que más ejercen este tipo de conducta.


The goal of this study was to compare prevalence of certain violent behaviors at the same educational level in two cross-sectional studies; the first one, carried out during the 2004-2005 academic course, and the second one three years later, during the 2007-2008 academic course. For this purpose, a total sample of 1.475 subjects, between 14 and 16 years of age, was analyzed. The results show that there is a significant decrease in the prevalence of almost all the violent behaviors analyzed, such as: insults, fights, etc., during the above-mentioned academic courses. However, the females suffer more indirect verbal aggression and, in contrast, the males perform this kind of behavior more frequently.


Asunto(s)
Universidades , Violencia/psicología
5.
PLoS Negl Trop Dis ; 2(9): e284, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18846230

RESUMEN

Cysticercosis is caused by Taenia solium, a parasitic disease that affects humans and rurally bred pigs in developing countries. The cysticercus may localize in the central nervous system of the human, causing neurocysticercosis, the most severe and frequent form of the disease. There appears to be an association between the prevalence of porcine cysticercosis and domestic pigs that wander freely and have access to human feces. In order to assess whether the risk of cysticercosis infection is clustered or widely dispersed in a limited rural area, a spatial analysis of rural porcine cysticercosis was applied to 13 villages of the Sierra de Huautla in Central Mexico. Clustering of cases in specific households would indicate tapeworm carriers in the vicinity, whereas their dispersal would suggest that the ambulatory habits of both humans and pigs contribute to the spread of cysticercosis. A total of 562 pigs were included in this study (August-December 2003). A global positioning system was employed in order to plot the geographic distribution of both cysticercotic pigs and risk factors for infection within the villages. Prevalence of pig tongue cysticercosis varied significantly in sampled villages (p = 0.003), ranging from 0% to 33.3% and averaging 13.3%. Pigs were clustered in households, but no differences in the clustering of cysticercotic and healthy pigs were found. In contrast, the presence of pigs roaming freely and drinking stagnant water correlated significantly with porcine cysticercosis (p = 0.07), as did the absence of latrines (p = 0.0008). High prevalence of porcine cysticercosis proves that transmission is still quite common in rural Mexico. The lack of significant differentiation in the geographical clustering of healthy and cysticercotic pigs weakens the argument that focal factors (e.g., household location of putative tapeworm carriers) play an important role in increasing the risk of cysticercosis transmission in pigs. Instead, it would appear that other wide-ranging biological, physical, and cultural factors determine the geographic spread of the disease. Extensive geographic dispersal of the risk of cysticercosis makes it imperative that control measures be applied indiscriminately to all pigs and humans living in this endemic area.


Asunto(s)
Cisticercosis/veterinaria , Enfermedades de los Porcinos/parasitología , Animales , Portador Sano , Cisticercosis/epidemiología , Cisticercosis/transmisión , Heces/parasitología , Geografía , Humanos , México/epidemiología , Densidad de Población , Prevalencia , Factores de Riesgo , Población Rural , Porcinos , Enfermedades de los Porcinos/epidemiología , Taenia solium , Clima Tropical
6.
Vaccine ; 26(23): 2899-905, 2008 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-18440675

RESUMEN

In search of reducing vaccine production costs', a recombinant M13 phage version of the anti-cysticercosis tripeptide vaccine (S3Pvac) was developed. The efficacy of S3Pvac-Phage vs. placebo was evaluated in a randomized trial that included 1,047 rural pigs in 16 villages of Central Mexico. Three to five months after vaccination 530 pigs were examined by tongue inspection. At 5-27 months of age, 331 pigs (197 vaccinated/134 controls) were inspected at necropsy. Vaccination reduced 70% the frequency of tongue cysticercosis and, based on necropsy, 54% of muscle-cysticercosis and by 87% the number of cysticerci.


Asunto(s)
Antígenos Helmínticos/inmunología , Bacteriófago M13/inmunología , Cisticercosis/inmunología , Cisticercosis/veterinaria , Enfermedades de los Porcinos/inmunología , Enfermedades de los Porcinos/prevención & control , Taenia solium/inmunología , Vacunas/inmunología , Vacunas/uso terapéutico , Envejecimiento/inmunología , Animales , Antígenos Helmínticos/biosíntesis , Bacteriófago M13/metabolismo , Cisticercosis/prevención & control , México , Población Rural , Porcinos , Enfermedades de los Porcinos/parasitología , Vacunas de Productos Inactivados/inmunología , Aumento de Peso/efectos de los fármacos
7.
Pharmacol Biochem Behav ; 88(3): 332-40, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17915301

RESUMEN

In male rats, the antidepressant-like effect of fluoxetine (FLX) and desipramine (DMI) in the forced swimming test (FST) is reduced by orchidectomy and partially restored by testosterone (T). It is unknown if this modulation of T is produced by its estrogenic metabolites. The objectives of this study were to evaluate if the aromatase inhibitor, formestane, interferes with the antidepressant-like effect of DMI and FLX in intact male rats, and to analyze if 17beta-estradiol (E2) modifies the FST and interacts with the antidepressants in orchidectomized (Orx) males. Intact males received DMI (1.25-5.0 mg/kg) and FLX (2.5-10 mg/kg) alone or in combination with formestane (17.5 mg/kg). Orx rats received E2 (5, 10, 20 and 40 microg/rat) or the combination of E2 [at sub-threshold (5 microg/rat) and optimal (10 microg/rat) doses] plus sub-effective doses of DMI (2.5 mg/kg) or FLX (10 mg/kg). Serum testosterone and estradiol levels were measured in intact-control and -formestane treated animals as well as in castrated males replaced with various doses of E2. Formestane in intact males lacked of an action in the FST, but cancelled the antidepressant-like effect of DMI and FLX. E2 at the supra-physiological doses of 10 and 20 microg/rat produced antidepressant-like effects. E2 at 5 microg/rat (that re-established the levels of this hormone to physiological levels) and at 10 microg/rat restored the antidepressant-like action of DMI and FLX in Orx rats. It was concluded that estrogens participate in the antidepressant-like effect of DMI and FLX in the FST.


Asunto(s)
Antidepresivos de Segunda Generación/farmacología , Antidepresivos Tricíclicos/farmacología , Desipramina/farmacología , Estrógenos/fisiología , Fluoxetina/farmacología , Androstenodiona/análogos & derivados , Androstenodiona/farmacología , Animales , Inhibidores de la Aromatasa/farmacología , Química Encefálica/efectos de los fármacos , Estradiol/sangre , Estradiol/farmacología , Femenino , Masculino , Actividad Motora/efectos de los fármacos , Orquiectomía , Ovariectomía , Ratas , Natación/psicología , Testosterona/sangre
8.
An. otorrinolaringol. mex ; 40(2): 63-7, mar.-mayo 1995. ilus, tab
Artículo en Español | LILACS | ID: lil-173936

RESUMEN

Se reportan los resultados de la medición de los niveles de contaminación por ruido, encontrados en seis horarios a lo largo de las 24 hr del día, en una de las principales avenidad de la ciudad de México en el año de 1993. Las mediciones se efectuaron mediante un sonómetro a las: 4.00, 8.00, 11.00, 15.00, 19.00 y 23.00 hr. El nivel de ruido en el percentil 10 (NR10) en los horarios estudiados fué de 80.3, 104.8, 100.9, 103.8, 95.6 y 95.2 dB "A" a las 4.00, 8.00, 11.00, 15.00, 19.00 y 23.00 hrs. respectivamente. El nivel de ruido en el percentil 50 (NR50) en los horarios estudiados fué de 67.7, 90.5, 87.5, 90.5, 86.5, y 77.2 dB "A" respectivamente. El nivel de ruido en el percentil 90 (NR90) fué de 60.2, 85.6, 82.1, 86.8, 84.7 y 73.9 dB "A". La correlación entre el ruido y la cantidad de automóviles circulantes fué de r=0.86. estos datos muestran que los niveles de ruido en calles de denso tráfico en la ciudad de México, se mantienen por arriba de la norma considerad como saludable (70 dB), a lo largo del día asociados al tráfico automotor


Asunto(s)
Contaminación del Aire , Automóviles/normas , Contaminación Ambiental/efectos adversos , Contaminación del Aire/estadística & datos numéricos , Contaminantes Ambientales/toxicidad , Contaminación Difusa , Ruido del Transporte/estadística & datos numéricos , Emisiones de Vehículos/efectos adversos
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