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1.
Avian Dis ; 66(1): 106-111, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35308012

RESUMEN

In the last decade, monitoring Marek's disease (MD) vaccination by real-time PCR has become a common practice. Evaluating in vivo replication of MD vaccines in the feather pulp (FP) at 7 days of age provides information on how well a flock has been vaccinated. Factors such as vaccine dose, combination with other vaccines, age and route of vaccination, and the origin of the vaccine can influence the results and need to be taken into consideration. Early infection with oncogenic MD virus (MDV) could also affect how vaccines replicate in the first week and therefore might influence the results. The objective of this study was to evaluate if coinfection with oncogenic MDV could affect MD vaccine DNA viral load in the FP at 7 days of age. A retrospective study was done using data from nine animal experiments (46 treatment groups) in which chickens were vaccinated against MD either in ovo or at 1 day of age and challenged with various oncogenic strains at 1 day of age by contact. In each experiment, vaccinated but not challenged groups were used as controls. Replication of MD vaccine was evaluated in samples of FP collected at 7 days of age by real-time PCR, and percentage of positives and vaccine load were analyzed. Our results show that CVI-988 (13 treatment groups), SB-1 (six treatment groups), and in most cases turkey herpesvirus (HVT; 24 out of 27 treatment groups) replication was not affected by early infection with oncogenic MDV. There were three treatment groups in which HVT replication differed between challenged and unchallenged chickens, however the effect was not clear; replication of HVT in nonchallenged chickens was higher (one treatment group) or lower (two treatment groups) than in challenged chickens and factors other than coinfection with MDV might have contributed to such differences.


Nota de investigación­El desafío temprano con un virus oncogénico de la enfermedad de Marek no interfiere con la carga de ADN de las vacunas contra la enfermedad de Marek en la pulpa de la pluma a los siete días de edad. En la última década, el seguimiento de la vacunación contra la enfermedad de Marek (EM) mediante PCR en tiempo real se ha convertido en una práctica común. La evaluación de la replicación in vivo de las vacunas de Marek en la pulpa de la pluma (FP) a los siete días de edad proporciona información sobre qué tan bien se ha vacunado una parvada. Factores como la dosis de la vacuna, la combinación con otras vacunas, la edad, la vía de vacunación y el origen de la vacuna pueden influir en los resultados y deben tenerse en cuenta. La infección temprana con un virus de Marek oncogénico (MDV) también podría afectar la forma en que las vacunas se replican en la primera semana y por lo tanto, podría influir en los resultados. El objetivo de este estudio fue evaluar si la coinfección con un virus de Marek oncogénico podría afectar la carga viral del ADN de la vacuna de Marek en la pulpa de la pluma a los siete días de edad. Se realizó un estudio retrospectivo utilizando datos de nueve experimentos con animales (46 grupos de tratamientos) en los que se vacunaron pollos contra la enfermedad de Marek ya sea in ovo o al día de edad y se desafiaron con varias cepas oncogénicas al día de edad por contacto. En cada experimento, se utilizaron como controles los grupos vacunados, pero no desafiados. Se evaluó la replicación de la vacuna de Marek en muestras de pulpa de la pluma recolectadas a los siete días de edad por PCR en tiempo real, y se analizó el porcentaje de positivos y la carga vacunal. Los resultados de este estudio muestran que la replicación de la cepa CVI-988 (13 grupos de tratamiento), la cepa SB-1 (seis grupos de tratamiento) y en la mayoría de los casos, del herpesvirus de pavo (HVT; 24 de 27 grupos de tratamiento) no se vio afectada por la infección temprana con un virus de Marek oncogénico. Hubo tres grupos de tratamiento en los que la replicación de la vacuna HVT difería entre pollos desafiados y no desafiados, sin embargo, el efecto no fue claro; la replicación de la vacuna HVT en pollos no desafiados fue mayor (un grupo de tratamiento) o menor (dos grupos de tratamiento) que en los pollos desafiados y otros factores distintos a la coinfección con el virus de la enfermedad de Marek podrían haber contribuido a tales diferencias.


Asunto(s)
Coinfección , Herpesvirus Gallináceo 2 , Vacunas contra la Enfermedad de Marek , Enfermedad de Marek , Animales , Pollos , Coinfección/veterinaria , ADN Viral , Plumas , Herpesvirus Gallináceo 2/genética , Estudios Retrospectivos
2.
Curr Med Chem ; 20(2): 222-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23231090

RESUMEN

The design and development of radiolabelled steroid derivatives has been an important area of research due to their wellknown value in breast cancer targeting. The estrogen receptor (ER) and progesterone receptor (PR) are important biomarkers in the diagnosis, prognosis and follow-up of the therapeutic response of breast tumours. Thus, several radioligands based on estrogens and progestins have been proposed for targeted functional ER imaging. The aim of this review is to survey and analyze the developments in this field, which have led to the design of a number of PET steroid-based imaging agents, a few of which seem to be promising as radiopharmaceuticals for detection of ER-positive breast tumours.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Sistemas de Liberación de Medicamentos , Radioisótopos de Flúor/química , Tomografía de Emisión de Positrones , Receptores de Esteroides/agonistas , Diagnóstico por Imagen , Femenino , Radioisótopos de Flúor/farmacología , Humanos , Ligandos
3.
J Med Entomol ; 49(4): 903-16, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22897051

RESUMEN

West Nile virus (family Flaviviridae, genus Flavivirus, WNV) is now endemic in California across a variety of ecological regions that support a wide diversity of potential avian and mammalian host species. Because different avian hosts have varying competence for WNV, determining the blood-feeding patterns of Culex (Diptera: Culicidae) vectors is a key component in understanding the maintenance and amplification of the virus as well as tangential transmission to humans and horses. We investigated the blood-feeding patterns of Culex tarsalis Coquillett and members of the Culex pipiens L. complex from southern to northern California. Nearly 100 different host species were identified from 1,487 bloodmeals, by using the mitochondrial gene cytochrome c oxidase I (COI). Cx. tarsalis fed on a higher diversity of hosts and more frequently on nonhuman mammals than did the Cx. pipiens complex. Several WNV-competent host species, including house finch and house sparrow, were common bloodmeal sources for both vector species across several biomes and could account for WNV maintenance and amplification in these areas. Highly competent American crow, western scrub-jay and yellow-billed magpie also were fed upon often when available and are likely important as amplifying hosts for WNV in some areas. Neither species fed frequently on humans (Cx. pipiens complex [0.4%], Cx. tarsalis [0.2%]), but with high abundance, both species could serve as both enzootic and bridge vectors for WNV.


Asunto(s)
Aves/parasitología , Culex/fisiología , Interacciones Huésped-Parásitos , Insectos Vectores/fisiología , Animales , California , Gatos , Bovinos , Perros , Conducta Alimentaria , Femenino , Humanos , Ratones , Ratas , Fiebre del Nilo Occidental/transmisión
4.
Mol Ecol Resour ; 12(2): 238-46, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22136215

RESUMEN

For vectorborne infections, host selection by bloodfeeding arthropods dictates the interaction between host and pathogen. Because Culex mosquitoes that transmit West Nile virus (WNV) feed both on mammalian and avian hosts with varying competence, understanding the bloodfeeding patterns of these mosquitoes is important for understanding the transmission dynamics of WNV. Herein, we describe a new microsphere-based assay using Luminex xMAP® technology to rapidly identify 15 common hosts of Culex mosquitoes at our California study sites. The assay was verified with over 100 known vertebrate species samples and was used in conjunction with DNA sequencing to identify over 125 avian and mammalian host species from unknown Culex bloodmeals, more quickly and with less expense than sequencing alone. In addition, with multiplexed labelled probes, this microsphere array identified mixed bloodmeals that were difficult to discern with traditional sequencing. The microsphere set was easily expanded or reduced according to host range in a specific area, and this assay has made it possible to rapidly screen thousands of Culex spp. bloodmeals to extend our understanding of WNV transmission patterns.


Asunto(s)
Aves/genética , Culex/fisiología , Ensayos Analíticos de Alto Rendimiento/métodos , Insectos Vectores/fisiología , Mamíferos/genética , Reacción en Cadena de la Polimerasa/métodos , Animales , Aves/clasificación , Sangre , Culex/virología , Conducta Alimentaria , Ensayos Analíticos de Alto Rendimiento/instrumentación , Especificidad del Huésped , Humanos , Insectos Vectores/virología , Mamíferos/clasificación , Mamíferos/virología , Reacción en Cadena de la Polimerasa/instrumentación
5.
Mol Ecol ; 16(3): 639-49, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17257119

RESUMEN

The principal vector of malaria in sub-Saharan Africa, Anopheles gambiae is subdivided into two molecular forms M and S. Additionally, several chromosomal forms, characterized by the presence of various inversion polymorphisms, have been described. The molecular forms M and S each contain several chromosomal forms, including the Savanna, Mopti and Forest forms. The M and S molecular forms are now considered to be the reproductive units within A. gambiae and it has recently been argued that a low recombination rate in the centromeric region of the X chromosome has facilitated isolation between these forms. The status of the chromosomal forms remains unclear however. Therefore, we studied genetic differentiation between Savanna S, Forest S, Forest M and Mopti M populations using microsatellites. Genetic differentiation between Savanna S and Forest S populations is very low (F(ST) = 0.0053 +/- 0.0049), even across large distances. In comparison, the Mopti M and Forest M populations show a relatively high degree of genetic differentiation (F(ST) = 0.0406 +/- 0.0054) indicating that the M molecular form may not be a single entity, but could be subdivided into at least two distinct chromosomal forms. Previously it was proposed that inversions have played a role in the origin of species within the A. gambiae complex. We argue that a possible subdivision within the M molecular form could be understood through this process, with the acquisition of inversions leading to the expansion of the M molecular form into new habitat, dividing it into two distinct chromosomal forms.


Asunto(s)
Anopheles/clasificación , Anopheles/genética , Alelos , Animales , Camerún , Inversión Cromosómica , Cromosomas/genética , Ecosistema , Femenino , Especiación Genética , Desequilibrio de Ligamiento , Malí , Filogenia
6.
J Med Entomol ; 42(4): 596-603, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16119548

RESUMEN

Previous studies have shown that sympatric populations of M and S molecular forms of Anopheles gambiae sensu stricto exhibit strong assortative mating. In the few documented cases of cross-mating between M and S forms, females that mated with amale of the alternative form were often also mated with a male of their own form. A potential explanation for the association between cross-mating and double mating could be that male accessory gland or sperm proteins that are responsible for inducing refractoriness to further mating by females have diverged between the M and S forms. This mechanism of postmating reproductive isolation would have important implications for our understanding of the speciation processes in the An. gambiae complex. We tested for this mechanism, by comparing the likelihood of mating, feeding, and laying eggs, as well as the fertility of females presented with males of their own form or the alternate form in the laboratory. We also compared the likelihood of remating in cross-mated and assortatively-mated females, and we analyzed their progeny to unravel patterns of sperm precedence. We found that cross-mated females differed from assortatively-mated females only in terms of egg-hatching rate and larval survival but that these effects could be attributed to hybrid vigor rather than differential response to seminal products. Cross-mating between forms was not associated with remating behavior. These results indicate that the sex proteins responsible for inhibiting further insemination and triggering the gonotrophic cycle in females have not diverged between these M and S populations. We discuss alternative explanations for the patterns of cross-mating and multiple mating observed in the field.


Asunto(s)
Anopheles/fisiología , Conducta Sexual Animal , Animales , Anopheles/genética , Conducta Animal/fisiología , Cruzamientos Genéticos , Femenino , Masculino , Semen/fisiología
7.
J Insect Physiol ; 49(12): 1085-92, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14624880

RESUMEN

To counteract water loss due to excretion, cuticular transpiration and respiration, various groups of arthropods have developed mechanisms for active uptake of water vapor from unsaturated air. In this study, active uptake capabilities and water loss rates were examined in the various developmental stages of the cat flea, Ctenocephalides felis. To determine critical equilibrium humidity, the lowest relative humidity at which active water uptake can occur, pre-desiccated immature and adult fleas were placed in a series of humidity regimes ranging from 44 to 93% RH. Active uptake occurred in larval stages at relative humidities above 53% and in pre-pupae at 75-93% RH. Pupae and adults did not demonstrate active uptake at any humidity. Optimal uptake for larvae occurred between 20 and 30 degrees C. When placed over Drierite (<10% RH), larval and adult stages demonstrated a higher rate of water loss than pre-pupal and pupal stages. Active water uptake is necessary to ensure proper development of the larvae of C. felis. Active uptake ceases after the larval-pupal ecdysis and it appears that adults have lost the ability to actively uptake water.


Asunto(s)
Siphonaptera/metabolismo , Agua/metabolismo , Animales , Peso Corporal , Humedad , Larva/metabolismo , Estadios del Ciclo de Vida/fisiología , Pupa/metabolismo , Siphonaptera/fisiología , Análisis de Supervivencia , Temperatura , Pérdida Insensible de Agua
8.
Ultrason Sonochem ; 10(4-5): 209-16, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12818384

RESUMEN

This paper describes recent studies in organic sonoelectrochemistry at Coventry University, including the oxidation of thiophene monoxides, degradation of dye pollutants, formation of conducting polymers and electrosynthetic modification of proteins.


Asunto(s)
Química Orgánica/métodos , Electroquímica/métodos , Ultrasonido , Animales , Compuestos Azo/química , Colorantes/química , Humanos , Oxidación-Reducción , Polímeros/química , Proteínas/química , Tiofenos/química
9.
Appl Radiat Isot ; 54(2): 227-39, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11200884

RESUMEN

The synthesis of two novel radiolabelled estrogen derivatives, [125I](E)-3-methoxy-17alpha-iodovinylestra-1,3,5(10),6-tetraen-17beta-ol (E[125I]IVDE) and [125I](Z)-3-methoxy-17alpha-iodovinylestra-1,3,5(10),6-tetraen-17beta-ol (Z[125I]IVDE), was carried out aiming to study the influence of the introduction of a C6-C7 double bond on the biological properties of the estradiol molecule. 3-Methoxyestra-1,3,5(10),6-tetraen-17-one was synthesised starting from a suitably protected estrone and subsequently converted into the 17alpha-ethynyl derivative. The radioiodinated derivatives were stereoselectively formed by radioiododestannylation of the corresponding tributylstannyl precursors. The biodistribution of the novel [125I]iodovinylestradiol derivatives was evaluated in immature female mice. Biological data indicated that the Z-isomer, owing to its higher in vivo uptake by the target tissue, has the preferable configuration for further development of similar compounds for estrogen receptor detection.


Asunto(s)
Congéneres del Estradiol/síntesis química , Congéneres del Estradiol/farmacocinética , Estradiol/análogos & derivados , Estradiol/síntesis química , Estradiol/farmacocinética , Animales , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Radioisótopos de Yodo , Ratones , Cintigrafía , Receptores de Estrógenos/metabolismo , Estereoisomerismo , Distribución Tisular , Útero/metabolismo
10.
Acta Crystallogr C ; 56 Pt 11: 1367-8, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11077301

RESUMEN

In the title compound, pentacyclo[11.8.1.1(3,11).0(7,23).0(15, 20)]tricosa-3,5,7,9,11(23),15,17,19-octaen-22-one, C(23)H(20)O, the bicyclo[5.4.1]dodecan-12-one moiety takes a rigid conformation in which the seven- and eight-membered rings take chair and boat-boat forms, respectively. The molecule has a non-crystallographic mirror symmetry perpendicular to the benzene and naphthalene planes.

11.
Artículo en Inglés | MEDLINE | ID: mdl-1083692

RESUMEN

The influence of leucomycine (10(-5) M--5 X 10(-3) M) on enzyme activities, free adenine nucleotides, and some intermediates of glycolysis in bovine lenses has been investigated. After a 48 h incubation in TCM 199, 6 out of 9 enzymes activities tested were decreased. Concentrations of energy rich nucleotifes, glucose, fructose, and fructose-6-phosphate as well as those of fructose-1,6-diphosphate and lactate were also decreased, whereas adenine monophosphate was increased.


Asunto(s)
Antibacterianos/farmacología , Cristalino/efectos de los fármacos , Leucomicinas/farmacología , Adenosina Monofosfato/análisis , Animales , Bovinos , Fructosafosfatos/análisis , Glucosa/análisis , Lactatos/análisis , Cristalino/análisis , Cristalino/enzimología , Cristalino/metabolismo , Factores de Tiempo
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