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1.
Sci Rep ; 11(1): 6912, 2021 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33767356

RESUMEN

Mastitis in cows is a major cause of economic losses and it is commonly associated with Staphylococcus aureus. Little is known about the S. aureus lineages causing mastitis in Mexican cattle. The aim of this study was to type S. aureus isolates causing mastitis in cows from the Comarca Lagunera region in Mexico in 2015-2016. Multi-locus variable number tandem repeat fingerprinting (MLVF) of 33 S. aureus isolates obtained from 210 milk samples revealed the MLVF clusters A (n = 1), B (n = 26), C (n = 5) and D (n = 1). Spa-typing showed that clusters A and B represent the spa-type t224, cluster C includes spa-types t3196 and t416, and cluster D represents spa-type t114. The different spa-types were mirrored by the masses of protein A bands as detected by Western blotting. Antimicrobial susceptibility testing showed that one isolate was susceptible to all antimicrobials tested, whereas all other strains were resistant only to benzylpenicillin. These findings show that only four S. aureus lineages, susceptible to most antimicrobials, were responsible for causing mastitis at the time of sampling. Lastly, many isolates carried the same small plasmid, designated pSAM1. The high prevalence of pSAM1 amongst the antimicrobial-susceptible isolates suggests an association with bovine colonization or mastitis rather than antimicrobial resistance.


Asunto(s)
Mastitis Bovina/microbiología , Resistencia a las Penicilinas , Staphylococcus aureus/genética , Animales , Bovinos , Femenino , México , Pruebas de Sensibilidad Microbiana , Repeticiones de Minisatélite , Tipificación de Secuencias Multilocus , Staphylococcus aureus/aislamiento & purificación
2.
Virus Genes ; 52(1): 81-90, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26728078

RESUMEN

Since the report of the initial outbreak of Porcine rubulavirus (PorPV) infection in pigs, only one full-length genome from 1984 (PorPV-LPMV/1984) has been characterised. To investigate the overall genetic variation, full-length gene nucleotide sequences of current PorPV isolates were obtained from different clinical cases of infected swine. Genome organisation and sequence analysis of the encoded proteins (NP, P, F, M, HN and L) revealed high sequence conservation of the NP protein and the expression of the P and V proteins in all PorPV isolates. The V protein of one isolate displayed a mutation that has been implicated to antagonise the antiviral immune responses of the host. The M protein indicated a variation in a short region that could affect the electrostatic charge and the interaction with the membrane. One PorPV isolate recovered from the lungs showed a mutation at the cleavage site (HRKKR) of the F protein that could represent an important factor to determine the tissue tropism and pathogenicity of this virus. The HN protein showed high sequence identity through the years (up to 2013). Additionally, a number of sequence motifs of very high amino acid conservation among the PorPV isolates important for polymerase activity of the L protein have been identified. In summary, genetic comparisons and phylogenetic analyses indicated that three different genetic variants of PorPV are currently spreading within the swine population, and a new generation of circulating virus with different characteristics has begun to emerge.


Asunto(s)
Infecciones por Rubulavirus/veterinaria , Rubulavirus/genética , Enfermedades de los Porcinos/virología , Animales , ADN Complementario , Brotes de Enfermedades/veterinaria , Genes Virales , Variación Genética , México/epidemiología , Filogenia , ARN Viral , Rubulavirus/clasificación , Infecciones por Rubulavirus/epidemiología , Infecciones por Rubulavirus/virología , Análisis de Secuencia de ARN , Porcinos , Enfermedades de los Porcinos/epidemiología , Proteínas Virales/genética
3.
J Parasitol ; 95(6): 1287-94, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19656000

RESUMEN

Hormones play a significant role in murine Taenia crassiceps cysticercosis, and they may also participate in the susceptibility to Taenia solium cysticercosis. In the present study, in vitro effects are reported for human chorionic gonadotropin (hCG) on the larval stages of T. crassiceps (WFU strain) and T. solium. Our results reveal the presence of receptors for hCG in different developmental phases of both cultured parasites. On day 30, both taeniid species had the highest percentage of receptors in the neck, strobila, and suckers, but these receptors decreased by day 60, delimiting the segments and the exterior of the developing proglottids in T. solium. At the same time, there was a large number of hCG receptors in the area of the presumptive cirrus organ and in calcareous corpuscles within the parenchyma. This is the first report detecting receptors for hCG on different larval stages of T. crassiceps and T. solium. A direct effect of hCG could be recognized by the cysticerci as a factor contributing to the growth and development of T. crassiceps and T. solium cysticerci, respectively.


Asunto(s)
Cysticercus/metabolismo , Receptores de HL/análisis , Taenia solium/metabolismo , Animales , Gonadotropina Coriónica/metabolismo , Medios de Cultivo , Cysticercus/crecimiento & desarrollo , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Cavidad Peritoneal/parasitología , Porcinos , Taenia solium/crecimiento & desarrollo
4.
J Comp Pathol ; 130(1): 1-6, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14693118

RESUMEN

Porcine rubulavirus (La Piedad-Michoacan virus) (PoRV-LPMV) is a member of the Paramyxoviridae family that causes encephalitis in young piglets and infertility in adult sows and boars. Infertility in sows naturally infected by PoRV-LPMV is characterized by an increased number of returns to oestrus, stillbirths and mummified fetuses. In this study, nine seronegative gilts were inoculated intranasally with the PAC-3 strain of PoRV-LPMV at week 6 or 10 of gestation. These animals were then killed at weeks 8 or 15 of gestation (seven gilts) or after natural parturition (two gilts). Four control gilts were mock-infected at gestation week 6 or 10 and killed between 2 and 4 weeks later. Gross lesions of focal congestion and haemorrhage were seen in the placenta and endometrium of one gilt infected at gestation week 6 and one infected at gestation week 10. PoRV-LPMV was isolated, at 2-6 weeks post-inoculation (pi), from lung, tonsils, ovary, placenta, uterus and lymph nodes of three of the gilts infected at gestation week 6 and at 2-3 weeks pi from lung, tonsil and ovary of two gilts infected at gestation week 10. Many of the fetuses of eight infected gilts were smaller than normal and had dermal ecchymoses. Dehydrated or mummified fetuses were present in six of the infected gilts but not in any control animal. PoRV-LPMV was isolated from brain, lung and liver of fetuses from two gilts infected at gestation week 6, and from two infected at gestation week 10. These results indicate that, after experimental infection, PoRV can replicate in tissues of seronegative pregnant gilts, cross the placenta, and cause fetal death and mummification.


Asunto(s)
Muerte Fetal/veterinaria , Complicaciones Infecciosas del Embarazo/veterinaria , Infecciones por Rubulavirus/veterinaria , Rubulavirus/patogenicidad , Enfermedades de los Porcinos/patología , Porcinos , Animales , Femenino , Muerte Fetal/etiología , Feto/patología , Feto/virología , Edad Gestacional , Placenta/patología , Embarazo , Complicaciones Infecciosas del Embarazo/patología , Rubulavirus/aislamiento & purificación , Rubulavirus/fisiología , Infecciones por Rubulavirus/patología , Infecciones por Rubulavirus/transmisión , Enfermedades de los Porcinos/transmisión
5.
Arch Med Res ; 32(5): 400-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11578755

RESUMEN

BACKGROUND: The porcine virus denominated La Piedad Michoacan Virus (LPMV) is a member of the family Paramyxoviridae and is the cause of a disease in pigs present only in Mexico. The disease is characterized by meningoencephalitis and respiratory distress in young pigs, epididymitis and orchitis in boars, and reproductive failure and abortion in sows. METHODS: The cytopathology, morphology, and distribution of the hemagglutination neuraminidase (HN) and nucleoprotein (NP) proteins of LPMV were investigated following inoculation into PK-15 cells. The cytopathic effect was characterized by cytoplasmic vacuolation and the formation of syncytia and cytoplasmic inclusion bodies. RESULTS: In immunofluorescence assays using a monoclonal antibody (MAb) against the HN protein at 5-60 min post-infection (early infection), a diffuse immunofluorescence was observed near the cell membrane and adjacent to the nuclear membrane. At 24 h post-infection (late infection), a dust-like immunofluorescence was observed throughout the cytoplasm. LPMV-infected cells incubated with the MAb against the NP protein showed punctate cytoplasmic fluorescence during the early stages of infection. At the late infection stage, these fluorescent particles became larger and were seen predominantly in the cytoplasm of syncytia. This pattern was also apparent by immunohistochemical labeling and immunogold electron microscopy. The latter technique revealed that HN protein was diffusely distributed throughout the cytoplasm. When using the MAb against the NP protein, nucleocapsid organization was the most prominent feature and resulted in the formation of cytoplasmic inclusion bodies visible by light and electron microscopy. Immunogold labeling of purified nucleocapsids was shown by electron microscopy. Virus particles and nucleocapsids were morphologically similar to members of the Paramyxoviridae family. CONCLUSIONS: The morphologic characteristics of the virions and the distribution patterns of the HN and NP proteins in PK-15 infected cells indicate that the mechanisms of LPMV replication are generally similar to those of the members of the Paramyxoviridae family.


Asunto(s)
Nucleoproteínas , Infecciones por Rubulavirus/veterinaria , Rubulavirus/fisiología , Animales , Línea Celular , Membrana Celular/virología , Núcleo Celular/virología , Citoplasma/virología , Femenino , Proteína HN/análisis , Inmunohistoquímica , Cuerpos de Inclusión Viral/ultraestructura , Riñón/citología , Masculino , México/epidemiología , Microscopía Electrónica , Microscopía Fluorescente , Proteínas de la Nucleocápside , Rubulavirus/inmunología , Rubulavirus/ultraestructura , Infecciones por Rubulavirus/epidemiología , Infecciones por Rubulavirus/virología , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/virología , Proteínas del Núcleo Viral/análisis , Virión/ultraestructura
8.
Vet Immunol Immunopathol ; 64(4): 367-81, 1998 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-9764728

RESUMEN

The immune response against the porcine rubulavirus was analyzed in experimentally infected adult pigs. High titers of virus neutralizing and hemagglutinating inhibitory antibodies were identified in infected animals. The antibody specificity was directed towards HN, M, and NP rubula virion proteins; immunodominance of HN proteins was demonstrated. Peripheral blood mononuclear cells from infected, but not from non-infected pigs proliferated in vitro in response to virus antigenic stimuli, showing a bell-shaped plot with the highest peak at 5 weeks post-infection. Virus-induced lymphoblasts expressed CD4+ CD8+ phenotype, whereas lectin-induced lymphoblasts were mainly identified as CD4+ CD8- cells. Phenotype analysis of freshly prepared PBMC revealed increased number of both monocytes (PoM1+) and total T lymphocytes (CD2+) early during infection, with reduced values of B lymphocytes at 4 weeks post-infection. Decrease in CD4+ CD8- blood cells was observed at 3 weeks post-infection, whereas both CD4- CD8+ and CD4+ CD8+ cells increased 1 and 4 weeks post-infection, respectively. This work discusses the relevance of CD4+ CD8+ T cells in the control of porcine rubulavirus infection.


Asunto(s)
Infecciones por Rubulavirus/veterinaria , Rubulavirus/inmunología , Enfermedades de los Porcinos/inmunología , Animales , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos , Especificidad de Anticuerpos , Antígenos Virales/inmunología , Activación de Linfocitos , Recuento de Linfocitos , Masculino , Infecciones por Rubulavirus/inmunología , Porcinos/inmunología
11.
Rev ADM ; 46(1): 15-7, 1989.
Artículo en Español | MEDLINE | ID: mdl-2634417

RESUMEN

An investigation work is presented about epidemiologic prevalence that describes the quantity of disorders existing of focal epithelial hyperplasia in a particular population. The results obtained showed low levels of such alterations, with what was concluded that such alteration does not represent a public health problem in the studied zone.


Asunto(s)
Enfermedades de la Boca/epidemiología , Mucosa Bucal/patología , Adolescente , Niño , Epitelio/patología , Humanos , Hiperplasia/epidemiología , México/epidemiología
13.
Arch Virol ; 93(1-2): 131-7, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3028340

RESUMEN

Human papillomavirus (HPV) type 13 DNA was detected in focal epithelial hyperplasia lesions of the oral mucosa in seven half-caste mexicans. The lesions contained intracellular papillomavirus-like particles with a diameter of about 50 nm. DNA extracted from biopsies contained unintegrated HPV type 13 DNA genomes as revealed by Southern blot hybridization. The HPV 13 DNA that was isolated in the present study had the same restriction enzyme cleavage map as HPV 13 DNA, previously described by others. It was moreover confirmed that HPV type 13 genome is related to the genomes of HPV types 6 and 11.


Asunto(s)
Papillomaviridae/análisis , Enfermedades de la Piel/microbiología , ADN Viral/análisis , Epitelio/microbiología , Epitelio/patología , Humanos , Hiperplasia/microbiología , Hibridación de Ácido Nucleico , Enfermedades de la Piel/patología
19.
Arch. invest. méd ; 15(2): 109-17, 1984.
Artículo en Inglés | LILACS | ID: lil-21775

RESUMEN

Se estudiaron por microscopia electronica de barrido y arteriografia los cambios hematologicos y la reaccion endotelial en la arteria carotida de la rata (calibre de 1 a 1.2 mm) en la que previamente se habian hecho seccion transversal y, a continuacion, anastomosis terminoterminal. Desde los tres minutos se restablecio el flujo y se observo trombogenesis. Esta trombogenesis fue minima y transitoria, y no disminuyo significativamente el flujo arterial


Asunto(s)
Femenino , Animales , Ratas , Derivación Arteriovenosa Quirúrgica , Arterias Carótidas , Microscopía Electrónica de Rastreo
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