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1.
Ecotoxicol Environ Saf ; 281: 116646, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38954906

RESUMEN

Agricultural production relies heavily on the use of pesticides, which may accumulate in soil and water, posing a significant threat to the global ecological environment and biological health. Butachlor is a commonly used herbicide and environmental pollutant, which has been linked to liver and kidney damage, as well as neurological abnormalities. However, the potential impact of butachlor exposure on the gut microbiota remains understudied. Thus, our aim was to investigate the potential negative effects of butachlor exposure on host health and gut microbiota. Our results demonstrated that butachlor exposure significantly reduced the host antioxidant capacity, as evidenced by decreased levels of T-AOC, SOD, and GSH-Px, and increased levels of MDA. Serum biochemical analysis also revealed a significant increase in AST and ALT levels during butachlor exposure. Microbial analysis showed that butachlor exposure significantly reduced the abundance and diversity of gut microbiota. Furthermore, butachlor exposure also significantly altered the gut microbial composition. In conclusion, our findings indicate that butachlor exposure can have detrimental health effects, including dysregulation of antioxidant enzymes, abnormalities in transaminases, and hepatointestinal damage. Furthermore, it disrupts the gut microbial homeostasis by altering microbial composition and reducing diversity and abundance. In the context of the increasingly serious use of pesticides, this study will help provide impetus for standardizing the application of pesticides and reducing environmental pollution.

2.
Microb Pathog ; 185: 106441, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37944676

RESUMEN

Increasing evidence indicated that the gut microbiota is a large and complex organic combination, which is closely related to the host health. Diarrhea is a disease with devastating effects on livestock that has been demonstrated to be associated with gut microbiota. Currently, studies on gut microbiota and diarrhea have involved multiple species, but changes in gut microbiota of Beigang pigs during diarrhea have not been characterized. Here, we described gut microbial changes of Beigang pigs during diarrhea. Results indicated that a total of 4423 OTUs were recognized in diarrheic and healthy Beigang pigs, and Firmicutes and Bacteroidota were the most dominant phyla regardless of health status. However, the major components of the gut microbiota changed between diarrheic and healthy Beigang pigs. Bacterial taxonomic analysis revealed that the relative abundances of 3 phyla (Synergistota, Actinobacteriota and Spirochaetota) and 30 genera increased significantly during diarrhea, whereas the relative abundances of 3 phyla (Patescibacteria, Bacteroidota and Fibrobacterota) and 41 genera decreased significantly. In conclusion, this study found significant changes in the gut microbiota of Beigang pigs during diarrhea. Meanwhile, this also lays the foundation for the prevention and treatment of diarrhea in Beigang pigs and the further discovery of more anti-diarrhea probiotics.


Asunto(s)
Microbioma Gastrointestinal , Animales , Porcinos , Diarrea/veterinaria , Diarrea/microbiología , Bacterias/genética , Bacteroidetes , Firmicutes
3.
Microb Pathog ; 185: 106444, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37951410

RESUMEN

Bovine parainfluenza virus type 3 (BPIV3) is a viral respiratory pathogen of cattle that causes substantial economic losses. A replicating-defective recombinant human adenovirus type 5 (HAd5), carrying a fusion protein of BPIV3 genotype C (HAd5-F), was constructed and evaluated for its immunogenicity and protective efficacy in mice. After intramuscular injection with the HAd5-F, the IgG titers against F proteins increased to 1:102,400, and virus-neutralizing titers increased to 1:256, significantly higher than those in the group injected with inactivated BPIV3C in mice (p<0.05). The splenic CD4+/CD8+T lymphocytes and IFN-γ+/IL-4+ cytokine percentages were more significant in the HAd5-F group than those in the control group. A BPIV3C challenge in a mouse model was used to assess protective efficacy of the HAd5-F. The viral loads in the lungs and tracheas of mice immunized with the HAd5-F were significantly lower than those in the control group (p<0.0001). There were no significant histopathological alterations in the lungs of mice vaccinated with the HAd5-F. These findings suggested that the HAd5-F elicited excellent immunity against BPIV3C infection.


Asunto(s)
Adenoviridae , Virus de la Parainfluenza 3 Humana , Animales , Bovinos , Humanos , Ratones , Adenoviridae/genética , Anticuerpos Antivirales , Virus de la Parainfluenza 3 Bovina/genética , Proteínas Recombinantes/genética , Genotipo
4.
Reprod Domest Anim ; 58(9): 1179-1187, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37492901

RESUMEN

The hypothalamic-pituitary-gonadal (HPG) axis connects the hypothalamus, pituitary gland, and gonads. The regulation of reproductive processes includes integrating various factors from structural functions and environmental conditions in the HPG axis, with the outcome indication of these processes being the pulsatile secretion of gonadotropin-releasing hormone (GnRH) from the hypothalamus. These factors include feed consumption and nutritional condition, sex steroids, season/photoperiod, pheromones, age, and stress. GnRH pulsatile secretion affects the pattern of gonadotropin secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which then regulates both endocrine function and gamete maturation in the gonads. This regulates gonadotropins and testosterone (T) production. There is evidence that in males, GnRH participates in a variety of host behavioural and physiological processes such as the release of reproductive hormones, progression of spermatogenesis and sperm function, aggressive behaviour, and physiological metabolism. GnRH activates receptors expressed on Leydig cells and Sertoli cells, respectively to stimulate T secretion and spermatogenesis in the testis. Photoperiod affects the reproductive system of the hypothalamic-pituitary axis via rhythmic diurnal melatonin secretion. Increased release of melatonin promotes sexual activity, GnRH production, LH stimulation, and T production. This induces testicular functions, spermatogenesis, and puberty. GnRH reduces the release of LH by the pituitary through the cascade effect and decreases plasma concentration of T. Gut microbiota maintain sex steroid homeostasis and may induce reduction in reproduction productivity. Recently, findings of kisspeptin-neurokinin-dynorphin neuronal network in the brain have resulted in fast advances in how GnRH secretion is controlled. Emerging studies have also indicated that other neuropeptide analogues could be used in control reproduction procedures in various goat and sheep breeds. The Tibetan male sheep and goats reproduce on a seasonal basis and have high reproductive performance. This is a review for the role of GnRH in Tibetan male sheep and goats reproduction. This is intended to enhance reproductive knowledge for understanding the key roles of GnRH relating to male reproductive efficiency of Tibetan sheep or goats.


Asunto(s)
Hormona Liberadora de Gonadotropina , Melatonina , Masculino , Animales , Ovinos , Hormona Liberadora de Gonadotropina/farmacología , Cabras/metabolismo , Tibet , Semen/metabolismo , Hormona Luteinizante , Reproducción/fisiología
5.
High Educ (Dordr) ; : 1-18, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37362762

RESUMEN

Previous studies on Chinese overseas students have generally presumed a smooth transition from mobility to mobility capital and have lacked an ethnic perspective. In this study, we adopt mobility capital as an analytical lens to explore the life trajectories of a group of Tibetans with studying abroad experiences. Drawing on qualitative data through multiple methods, we find a shift from collective-oriented expectations regarding studying abroad to individualist life planning and lifestyles after returning to work in the Tibet Autonomous Region (TAR). Before studying abroad, the informants viewed such experiences as important capital that could be later used to make a change for the Tibetan group, their local societies, and the state. Those views met a different reality after returning to TAR because the informants generally felt they were being viewed as potentially risk subjects in the workplace, which significantly impeded the capitalization of educational mobility at the institutional level. However, the informants developed coping strategies to find self-worth in private life by capitalizing on educational mobility. By addressing the subjective experiences of Tibetan informants in TAR and their associations with institutional contexts, this article not only engages an ethnicity-sensitive perspective to understand the politics of international educational mobility but also extends the discussion on individuals' experiences of educational mobility to the successional stage upon returning to their home societies. This article ultimately emphasizes the need for more culturally and politically reflexive policies that can sustain the flow of ethnic talents and help them realize their self-worth.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36674175

RESUMEN

Characteristics of the urban environment (e.g., building density and road network) can influence the spread and transmission of coronavirus disease 2019 (COVID-19) within cities, especially in high-density high-rise built environments. Therefore, it is necessary to identify the key attributes of high-density high-rise built environments to enhance modelling of the spread of COVID-19. To this end, case studies for testing attributes for modelling development were performed in two densely populated Chinese cities with high-rise, high-density built environments (Hong Kong and Shanghai).The investigated urban environmental features included 2D and 3D urban morphological indices (e.g., sky view factor, floor area ratio, frontal area density, height to width ratio, and building coverage ratio), socioeconomic and demographic attributes (e.g., population), and public service points-of-interest (e.g., bus stations and clinics). The modelling effects of 3D urban morphological features on the infection rate are notable in urban communities. As the spatial scale becomes larger, the modelling effect of 2D built environment factors (e.g., building coverage ratio) on the infection rate becomes more notable. The influence of several key factors (e.g., the building coverage ratio and population density) at different scales can be considered when modelling the infection risk in urban communities. The findings of this study clarify how attributes of built environments can be applied to predict the spread of infectious diseases. This knowledge can be used to develop effective planning strategies to prevent and control epidemics and ensure healthy cities.


Asunto(s)
COVID-19 , Humanos , Ciudades/epidemiología , COVID-19/epidemiología , China/epidemiología , Entorno Construido , Hong Kong
7.
Front Microbiol ; 13: 1108890, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36713149

RESUMEN

Introduction: Ensiling whole-crop oat (Avena sativa L.) has attracted a growing interest in the Qinghai-Tibet Plateau. The study aimed to investigate the microbial community and chemical composition of fresh and ensiling oat harvested from six different elevations of the Qinghai-Tibet Plateau. Method: The oat (A. sativa L. cv. Qingyin No. 1) was planted in six different sites across Qinghai-Tibet Plateau (BM, Bomi County; BY, Bayi County; DZ, Dazi County; BR, Biru County; SC, Suo County; SN, Seni County), where the elevations were in the range of 2,800-4,500 m above sea level (a. s. l.). Oat was harvested at the milk stage and ensiled for 90 days. Results: The highest crude protein (CP) and lowest water-soluble carbohydrate (WSC) were observed in fresh oat of SN and BM, respectively, however, no distinct gradient trend in WSC and CP concentrations along the elevation gradient. The lowest LAB counts in fresh oat from the highest elevational regions of SN. After 90 days of ensiling, the pH in all oat silages was lower than 4.2, and silages from SC and SN showed a lower pH and butyric acid concentration, and higher lactic acid (LA) concentration than silages of other regions. The oat silage from BR showed the lowest LA concentration and the highest pH. The bimodal distributions of fungal and bacterial richness in fresh oat along the elevation gradient were observed, while the elevation gradients did not affect the fungal Shannon index in fresh oat. Dioszegia, Cladosporium, and Vishniacozyma were the prevalent fungal genus in fresh oat, while Wickerhamomyces, Candida, and Saccharomyces dominated the fungal communities of silages. Wickerhamomyces and Candida were the dominant genera in oat silages from BM and SC, respectively. Erwinia, Paenibacillus, Pseudomonas, Leuconostoc, and Exiguobacterium dominated the bacterial community of fresh oat, while Lactobacillus and Kosakonia were the dominant bacterial genus in oat silages. Pantoea was the most dominant bacterial genus in fresh oat from low-elevational regions (BM, BY, and DZ). Oat from SN exhibited the best fermentation quality although fresh oat of SN hosted the lowest LAB counts, indicating that high-efficient LAB might be present in fresh oat sampled from high altitudes.

9.
Anim Reprod Sci ; 214: 106287, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32087914

RESUMEN

Estrogen receptor alpha (ERα) is a ligand-activated transcription factor that regulates cellular responses to estrogens and transcription processes of target genes. In this study, changes in DNA methylation and histone modifications in the promoter region and Exon 1 of the ERα gene were analyzed to ascertain epigenetic changes associated with increased ERα mRNA abundance during reproductive maturation from 90 (egg production not yet initiated) to 160 (after egg production was initiated) d of age (d post-hatching) in chicken ovaries. The results indicate there was no difference in CpG methylation at the promoter and Exon 1 except at the region analyzed with primer pairs F2 and R2, where percentage of methylated CpG of Sites 2 and 8 after reproductive maturation was greater compared with before reproductive maturation. By using the chromatin immunuoprecipitation (ChIP) assay combined with SYBR green quantitative PCR, effects of histone modifications were evaluated, including histone H3K4 di + tri methylation, H3K9 phosphorylation and trimethylation, H3K36 methylation and H3K27 acetylation on chicken ERα mRNA transcript abundance. The results indicated that there was a greater histone H3K27 acetylation and lesser H3K36 trimethylation associated with increased abundance of ERα mRNA transcript in chicken ovaries after reproductive maturation (90 compared with 160 d of age). In consistent with this finding, the relative abundance of transcriptional coactivator p300 mRNA transcript and protein in the ovaries was markedly greater in reproductively mature than immature chickens. Findings provide insights into the epigenetic regulations of the chicken ERα gene expression that is required for chicken ovarian development.


Asunto(s)
Pollos/metabolismo , Epigénesis Genética , Receptor alfa de Estrógeno/metabolismo , Ovario/crecimiento & desarrollo , ARN Mensajero/metabolismo , Maduración Sexual/fisiología , Animales , Receptor alfa de Estrógeno/genética , Femenino , Regulación del Desarrollo de la Expresión Génica/fisiología , Ovario/metabolismo , ARN Mensajero/genética
10.
Front Genet ; 10: 430, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31156697

RESUMEN

In hens, follicle selection is an important process affecting egg laying traits. This study investigated the role of parathyroid hormone-like hormone (PTHLH) in chicken follicle selection, its transcriptional regulation and genetic effects on egg laying traits. PTHLH and its receptor PTH1R were mainly expressed in follicles of 6-8 mm in diameter, exhibits differential expression pattern in the theca and granulosa cells of pre- and hierarchal follicles. PTHLH stimulates the proliferation of follicular granulosa and theca cells, the expression of StAR and CYP11A1 mRNA and the production of progesterone (P4) in pre-hierarchal follicles. Treatment with FSH increased PTHLH mRNA expression in pre-hierarchal follicular theca cells and hierarchal follicular granulosa cells. Two critical regions regulating chicken PTHLH transcription were revealed, each of which harbored a SNP: C>T (chr1: 72530014) for AP-1 and a SNP: A>G (chr1: 72531676). Hens with diplotype AC/GT were younger at first laying and laid more eggs at 32 weeks. The haplotype (G-1827T-165) with double mutations had the greatest promoter activity of chicken PTHLH transcription. Collectively, PTHLH plays an important role in chicken follicle selection by stimulating cell proliferation and steroidogenesis. Polymorphisms in chicken PTHLH promoter region are associated with egg laying traits by affecting the binding of transcription factor AP-1.

11.
Gene ; 642: 32-42, 2018 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-29128632

RESUMEN

In ovarian follicle development, estrogen acts as a regulatory molecule to mediate proliferation and differentiation of follicular cells. ERα (estrogen receptor α) exerts regulatory function classically by binding directly to the estrogen response element, recruiting co-factors and activating or repressing transcription in response to E2. In this study, we used ChIP-seq to map ERα-binding sites in ovaries of Hy-line Brown commercial hens at 45d, 90d and 160d. In total, 24,886, 21,680 and 23,348 binding sites were identified in the ovaries of hens at 45d, 90d and 160d, which are linked to 86, 83 and 74 genes, respectively. The PPI network contains 47 protein nodes and 164 interaction edges, among which, AKT1 (V-Akt Murine Thymoma Viral Oncogene Homolog 1) and ACTN2 (Actinin Alpha 2) with the highest weight in the network, followed by CREB1 (CAMP Responsive Element Binding Protein 1), and EPHA5 (EPH Receptor A5) were identified. These genes are likely related to sexual maturity in hens. This study also provides insight into the regulation of the ERα target gene networks and a reference for understanding ERα-regulated transcription.


Asunto(s)
Inmunoprecipitación de Cromatina/métodos , ADN/química , Receptor alfa de Estrógeno/metabolismo , Redes Reguladoras de Genes , Animales , Sitios de Unión , Pollos/crecimiento & desarrollo , ADN/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Ovario/química , Ovario/crecimiento & desarrollo , Mapas de Interacción de Proteínas , Elementos de Respuesta , Procesos de Determinación del Sexo
12.
Artículo en Inglés | MEDLINE | ID: mdl-29187833

RESUMEN

Ovarian follicle selection is an important process impacting the laying performance and fecundity of hens, and is regulated by follicle-stimulating hormone (FSH) through binding to its receptor [follicle-stimulating hormone receptor (FSHR)]. In laying hens, the small yellow follicle (6-8 mm in diameter) with the highest expression of FSHR will be recruited into the preovulatory hierarchy during ovarian follicle development. The study of molecular mechanism of chicken follicle selection is helpful for the identification of genes underlying egg-laying traits in chicken and other poultry species. Herein, the transcriptomes of chicken small yellow follicles differing in the mRNA expression of FSHR were compared, and a total of 17,993 genes were identified in 3 pairs of small yellow follicles. The Wnt signaling pathway was significantly enriched in the follicles with the greatest fold change in FSHR expression. In this pathway, the expression level of Wnt4 mRNA was significantly upregulated with a log2(fold change) of 2.12. We further investigated the expression, function, and regulation of Wnt4 during chicken follicle selection and found that Wnt4 mRNA reached its peak in small yellow follicles; Wnt4 stimulated the proliferation of follicular granulosa cells (GCs), increased the expression of StAR and CYP11A1 mRNA in prehierarchical and hierarchical follicles, increased the expression of FSHR mRNA, and decreased the expression of anti-Müllerian hormone and OCLN mRNA. Treatment with FSH significantly increased Wnt4 expression in GCs. Moreover, Wnt4 facilitated the effects of FSH on the production of progesterone (P4) and the mRNA expression of steroidogenic enzyme genes in the GCs of hierarchical follicles, but inhibited the effects of FSH in the GCs of prehierarchical follicles. Collectively, these data suggest that Wnt4 plays an important role in chicken follicle selection by stimulating GC proliferation and steroidogenesis. This study provides a theoretical basis for improving the egg-laying performance of chicken and a reference for the elucidation of the molecular mechanism of follicular selection in mammals.

13.
Trop Anim Health Prod ; 49(7): 1339-1344, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28624927

RESUMEN

A cross-sectional study was conducted in three counties (Damxung, Maizhokunggar and Yadong) in Tibet in April and May 2015. A total of 1,523 yaks owned by 181 herders were randomly selected and blood sampled. Sera were tested using the rose bengal test (RBT) and a competitive immune-enzymatic assay (C-ELISA) and the test results interpreted in parallel. The individual yak prevalence was 2.8% (95% CI 2.0-3.7) with a herd prevalence of 18.2% (95% CI 12.9-24.6). At the individual level, two predictor variables, age and production system, were significantly associated with seropositivity by a binary logistic regression analysis. The odds of Brucella infection were significantly higher in older Yaks (3-5 years old, OR = 4.51; 95% CI 1.53-19.29; ≥6 years old, OR = 3.89; 95% CI 1.23-17.21) compared to those of younger yaks (≤2 years old). The odds of seropositivity for yaks managed under an agro-pastoral production system were 2.9 (95% CI 1.48-5.86) times higher compared to those managed under a pastoral production system. At the herd level, an association between the infection with Brucella and a history of abortions in the herd was observed (OR = 4.98, 95% CI 1.48-16.62). Surprisingly, vaccination was not associated with a lower level of infection (p = 0.49 and p = 0.99 for individual and herd level data, respectively). The results of the survey indicate that bovine brucellosis is endemic among the yak population in the plateau region of China, and the risk factors identified in the study should be considered in the epidemiology of the disease and when developing control programs for the disease.


Asunto(s)
Brucella/aislamiento & purificación , Brucelosis Bovina/epidemiología , Animales , Brucelosis Bovina/microbiología , Bovinos , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática/veterinaria , Prevalencia , Factores de Riesgo , Rosa Bengala , Estudios Seroepidemiológicos , Tibet/epidemiología
14.
G3 (Bethesda) ; 6(5): 1305-12, 2016 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-26966259

RESUMEN

Extracelluar matrix undergoes constant remodeling, cell-cell, and cell-matrix interactions during chicken ovarian follicle growth, which is coordinated by matrix metalloproteinases (MMPs), and their associated endogenous inhibitors (TIMPs). Transcriptome analysis revealed upregulation of MMP13 in sexually mature chicken ovaries. In this study, we found that the expression of MMP13 in chicken ovary was stably elevated from 60 d to 159 d, and was significantly higher at 159 d than at the other three developmental stages (P < 0.05). The expression of MMP13 mRNA increased from SW (small white follicles) to F5 (fifth largest follicles), then decreased to F1 (first largest follicles), and dramatically increased again in POF1 (newly postovulatory follicles) follicles (P < 0.05). The MMP13 protein was localized in stroma cells and primordial follicles of sexually immature chicken ovaries, in the theca cell layers of all sized follicles of sexually mature chicken ovaries. Furthermore, we identified a positive element (positions -1863 to -1036) controlling chicken MMP13 transcription, and, in this region, six single nucleotide polymorphisms were found and genotyped in chicken populations. In the White Recessive Rock population, hens with A(-1356)-C(-1079)/A(-1356)-C(-1079) genotype had earlier "age at first laying" than those with G(-1356)-T(-1079)/G(-1356)-T(-1079) genotype (P < 0.05), and exhibited significantly lower transcriptional activity (P < 0.01). Collectively, chicken MMP13 plays an important role in ovarian follicle growth and regression, and polymorphisms in its promoter region could be used as molecular markers for improving the trait "age at first laying" in chicken breeding.


Asunto(s)
Pollos/genética , Expresión Génica , Metaloproteinasa 13 de la Matriz/genética , Polimorfismo Genético , Regiones Promotoras Genéticas , Carácter Cuantitativo Heredable , Reproducción/genética , Animales , Pollos/metabolismo , Huevos , Femenino , Inmunohistoquímica , Desequilibrio de Ligamiento , Metaloproteinasa 13 de la Matriz/metabolismo , Folículo Ovárico/metabolismo , Ovario/metabolismo , Eliminación de Secuencia
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