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1.
Viruses ; 16(3)2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38543692

RESUMEN

Infectious bronchitis virus (IBV) induces severe economic losses in chicken farms due to the emergence of new variants leading to vaccine breaks. The studied IBV strains belong to Massachusetts (Mass), Canadian 4/91, and California (Cal) 1737 genotypes that are prevalent globally. This study was designed to compare the impact of these three IBV genotypes on primary and secondary lymphoid organs. For this purpose, one-week-old specific pathogen-free chickens were inoculated with Mass, Canadian 4/91, or Cal 1737 IBV variants, keeping a mock-infected control. We examined the IBV replication in primary and secondary lymphoid organs. The molecular, histopathological, and immunohistochemical examinations revealed significant differences in lesion scores and viral distribution in these immune organs. In addition, we observed B-cell depletion in the bursa of Fabricius and the spleen with a significant elevation of T cells in these organs. Further studies are required to determine the functional consequences of IBV replication in lymphoid organs.


Asunto(s)
Infecciones por Coronavirus , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Vacunas Virales , Animales , Canadá , Pollos , Virus de la Bronquitis Infecciosa/genética , California , Genotipo , Massachusetts
2.
Viruses ; 15(12)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38140526

RESUMEN

Infectious bronchitis virus (IBV) is an avian coronavirus that causes a disease in chickens known as infectious bronchitis (IB). The pathogenesis of IBV and the host immune responses against it depend on multiple factors such as the IBV variant, breed and age of the chicken, and the environment provided by the management. Since there is limited knowledge about the influence of the sex of chickens in the pathogenesis of IBV, in this study we aim to compare IBV pathogenesis and host immune responses in young male and female chickens. One-week-old specific pathogen-free (SPF) White Leghorn male and female chickens were infected with Canadian Delmarva (DMV)/1639 IBV variant at a dose of 1 × 106 embryo infectious dose (EID)50 by the oculo-nasal route while maintaining uninfected controls, and these chickens were euthanized and sampled 4- and 11-days post-infection (dpi). No significant difference was observed between the infected male and female chickens in IBV shedding, IBV genome load in the trachea, lung, kidney, bursa of Fabricius (BF), thymus, spleen, and cecal tonsils (CT), and IBV-induced lesion in all the examined tissues at both 4 and 11 dpi. In addition, there was no significant difference in the percentage of IBV immune-positive area observed between the infected male and female chickens in all tissues except for the kidney, which expressed an increased level of IBV antigen in infected males compared with females at both 4 and 11 dpi. The percentage of B lymphocytes was not significantly different between infected male and female chickens in all the examined tissues. The percentage of CD8+ T cells was not significantly different between infected male and female chickens in all the examined tissues except in the trachea at 11 dpi, where female chickens had higher recruitment when compared with male chickens. Overall, although most of the findings of this study suggest that the sex of chickens does not play a significant role in the pathogenesis of IBV and the host immune response in young chickens, marginal differences in viral replication and host responses could be observed to indicate that IBV-induced infection in male chickens is more severe.


Asunto(s)
Infecciones por Coronavirus , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Animales , Masculino , Femenino , Pollos , Virus de la Bronquitis Infecciosa/fisiología , Canadá , Tráquea , Inmunidad
3.
Vaccines (Basel) ; 11(7)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37515032

RESUMEN

Infectious bronchitis virus (IBV) causes infectious bronchitis disease in chickens. IBV primarily infects the upper respiratory tract and then disseminates to other body systems including gastrointestinal, reproductive, and urinary systems. Unlike original IBV serotypes, the novel IBV variants target lymphoid organs, but information on this is scarce. In this study, we aim to evaluate the impact of the presence of maternal antibodies on IBV infection in primary and secondary lymphoid organs. Maternal antibody free, specific pathogen free (SPF) hens were divided into vaccinated and non-vaccinated groups. The progeny male chicks from these hens were divided into four groups; vaccinated challenged (VC), non-vaccinated challenged (NVC), vaccinated non-challenged (VNC), and non-vaccinated non-challenged (NVNC). The challenge groups were given 1 × 106 embryo infectious dose (EID)50 of IBV Delmarva (DMV)/1639 by the oculo-nasal route and non-challenge groups were given saline. The serum anti-IBV antibody titer was significantly higher in challenged groups compared to non-challenged groups. The IBV genome load was significantly lower in the VC group than NVC group in oropharyngeal and cloacal swabs and in bursa of Fabricius (BF) and cecal tonsils (CT). The histopathological lesion scores were significantly lower in VC group than NVC group in BF and CT. These findings suggest that the presence of maternal antibody in chicks could provide some degree of protection against IBV infection in BF and CT.

4.
Parasitol Int ; 90: 102618, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35777654

RESUMEN

The one-humped camel (Camelus dromedarius) or dromedary is an economically important domestic animal. However, infectious diseases, including those caused by vector-borne hemopathogens, frequently compromise the health and production of camels. In this study, we examined infections caused by Babesia, Theileria, Trypanosoma, and Anaplasma species in camels in Egypt. We analyzed blood DNA samples from 148 camels reared in six Egyptian governorates (Giza, Asyut, Sohag, Qena, Luxor, and the Red Sea) using pathogen-specific Polymerase Chain Reaction (PCR) assays. Our results indicated that 29 (19.6%), 22 (14.9%), 1 (0.7%), 2 (1.4%), 1 (0.7%), 2 (1.4%), and 28 (18.9%) of the surveyed animals were infected with Babesia bovis, B. bigemina, Babesia sp. Mymensingh, Theileria sp. Yokoyama, Theileria equi, Trypanosoma evansi, and Anaplasma marginale, respectively. We found that a total of 68 (45.9%) animals were infected with at least one of the detected hemopathogens. Sequencing analyses of PCR amplicons confirmed our diagnostic results. This study is the first to report Theileria sp. Yokoyama and Babesia sp. Mymensingh in Egypt. This is also the first report of infection with these two species in one-humped camel. In conclusion, this study found that camels in Egypt are infected with several vector-borne hemopathogens, including novel parasite species.


Asunto(s)
Anaplasmosis , Babesia , Babesiosis , Enfermedades de los Bovinos , Theileria , Trypanosoma , Anaplasma/genética , Anaplasmosis/epidemiología , Animales , Babesia/genética , Babesiosis/epidemiología , Babesiosis/parasitología , Camelus , Bovinos , Enfermedades de los Bovinos/parasitología , Egipto/epidemiología , Theileria/genética , Trypanosoma/genética
5.
Parasitol Int ; 80: 102199, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32961305

RESUMEN

Apicomplexan parasite Toxoplasma gondii has three distinct clonal lineages: high, medium and low virulent strains, type I, II and III, respectively. T. gondii avoids the immune response by transforming from fast multiplying tachyzoite to slow multiplying bradyzoite, and establishing a chronic infection. In the present study, we isolated a new strain of T. gondii from cat feces in the Tokachi subprefecture, Hokkaido, Japan and named it as TgCatJpObi1 (Obi1) strain. Genotyping analysis of 12 loci revealed atypical characters close to type II, genotype 4 according to ToxoDB classification. Phenotypically, Obi1 strain shows slow growth rate and the ability of spontaneous cyst formation in both human foreskin fibroblast (HFFs) and mouse peritoneal macrophages in vitro without bradyzoite induction. Parasite virulence was assessed by means of mouse survival upon infection with either Obi1 or ME49 strains. Obi1 strain displayed no mortalities in comparison to type II clonal lineage, ME49 at LD50 to LD100 range (1 × 103-106 tachyzoites). Although virulence of Obi1 strain is significantly lower than that of ME49, nucleotide sequences analyses revealed that genes of virulence factors such as Gra15, Rop5, 16, 17, and 18 in Obi1 strain were 100% identical to those in the type II strain. Thus, characterization of a newly isolated strain, Obi1, is crucial to clarify the development of toxoplasmosis in both humans and animals.


Asunto(s)
Enfermedades de los Gatos/parasitología , Toxoplasma/genética , Toxoplasma/patogenicidad , Factores de Virulencia/genética , Animales , Gatos , Heces/parasitología , Femenino , Japón , Ratones , Ratones Endogámicos BALB C , Organismos Libres de Patógenos Específicos , Toxoplasma/aislamiento & purificación , Virulencia/genética
6.
Behav Brain Funct ; 16(1): 9, 2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33158454

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a common neurodegenerative disorder characterized by progressive loss of nigrostriatal dopaminergic neurons leading to dopamine depletion and problems of movement, emotions, and cognition. While the pathogenesis of PD is not clear, damage of dopaminergic neurons by oxygen-derived free radicals is considered an important contributing mechanism. This study aimed to evaluate the role of treadmill exercise in male Wister rats as a single treatment and as an aid-therapy with L-dopa for rotenone-induced PD. To study the role of the Nrf2- ARE pathway as a mechanism involved in exercise-associated improvement in rotenone-induced PD in rats. METHOD: Animals were divided into 5 groups, (Control, rotenone, rotenone\exercise, rotenone\L-dopa, and rotenone\exercise\L-dopa (combination)groups). After the PD induction, rats in the rotenone\exercise and combination groups were daily treadmill exercised for 4 weeks. RESULTS: Treadmill exercise significantly improved behavioral and motor aspects of rotenone-induced PD. When treadmill exercise was introduced as a single intervention, it amended most behavioral aspects of PD, gait fully corrected, short-term memory, and motor coordination. Where L-dopa corrected locomotor activity and motor coordination but failed to improve short-term memory and only partially corrected the gait of rotenone-treated rats. When treadmill exercise was combined with L-dopa, all features of PD were corrected. It was found that exercise upregulated some of its associative genes to Nrf2 pathways such as TFAM, Nrf2 and NQO.1 mRNA expression. CONCLUSION: This study suggests that forced exercise improved parkinsonian like features by activating the Nrf2 pathway.


Asunto(s)
Antiparkinsonianos/uso terapéutico , Conducta Animal , Trastornos del Movimiento/terapia , Factor 2 Relacionado con NF-E2/fisiología , Neostriado/fisiología , Enfermedad de Parkinson Secundaria/terapia , Condicionamiento Físico Animal/psicología , Rotenona , Transducción de Señal/fisiología , Desacopladores , Animales , Trastornos Neurológicos de la Marcha/tratamiento farmacológico , Levodopa/uso terapéutico , Masculino , Memoria a Corto Plazo/efectos de los fármacos , Factor 2 Relacionado con NF-E2/genética , Neostriado/enzimología , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/psicología , Desempeño Psicomotor/efectos de los fármacos , Ratas , Ratas Wistar , Tirosina 3-Monooxigenasa/metabolismo , Regulación hacia Arriba/fisiología
7.
Biomed Res ; 28(6): 301-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18202520

RESUMEN

In the present study, we aimed to determine how inflammation affects spontaneous motility in the longitudinal direction of a hamster colon preparation. Trinitrobenzene sulfonic acid (TNBS) injected into the distal colon caused diarrhea 4-7 days after the treatment, but diarrhea was not observed in hamsters kept for 4 weeks. At 1 week after induction of colitis, spontaneous motility in the longitudinal direction was strongly suppressed. Contraction of longitudinal smooth muscles induced by electrical field stimulation was impaired, but not that induced by exogenously applied acetylcholine, indicating that acute inflammation preferentially impairs neurotransmissions with a minor effect on contractility of the longitudinal smooth muscle itself. The spontaneous motility reappeared in the colonic preparation isolated from the hamster maintained for 4 weeks after induction of colitis. The reappearance of the motility accompanied cholinergic and nitrergic regulations of contractile activity. These results demonstrated that impairment and following restoration of spontaneous contractile activity of longitudinal smooth muscles in the TNBS-inflamed distal colon of the hamster may depend on the damage and recovery of neural factors, rather than alteration of muscle contractility.


Asunto(s)
Colitis/fisiopatología , Colon/fisiopatología , Músculo Liso/fisiopatología , Animales , Colitis/inducido químicamente , Cricetinae , Diarrea/inducido químicamente , Diarrea/fisiopatología , Estimulación Eléctrica , Motilidad Gastrointestinal , Contracción Muscular , Ácido Trinitrobencenosulfónico
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