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1.
Front Vet Sci ; 10: 1166015, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37415968

RESUMEN

The rumen of ruminants is inhabited by complex and diverse microorganisms. Young animals are exposed to a variety of microorganisms from their mother and the environment, and a few colonize and survive in their digestive tracts, forming specific microflora as the young animals grow and develop. In this study, we conducted full-length sequencing of bacterial and fungal communities in the rumen of pastured yaks of different ages (from 5 days after birth to adulthood) using amplified sequencing technology. The results showed that the rumen microflora of Zhongdian yaks changed gradually from 5 to 180 days after birth and tended to stabilize at 2 years of age. The rumen of adult yaks was the most suitable for the growth and reproduction of most bacteria. Bactria diversity of the yak rumen increased gradually from 5 days after birth to adulthood. With the growth of yaks, different dominated bacteria were enriched in different groups, but Prevotella remained highly abundant in all groups. The yak rumen at 90 days of age was the most suitable for the growth and reproduction of most fungi, and 90 days of age could be a cut-off point for the distribution of fungal communities. Fungal Thelebolus was the firstly reported in yak rumen and was enriched in the yak rumen of 90 days after birth. The most abundant and balanced fungal genera were found in adult yaks, and most of them were only detected in adult yaks. Our study reported on the rumen bacterial and fungal communities of Zhongdian yaks grazed at different ages and provided insights into the dynamic changes of dominant microflora with yak growth.

2.
Comput Intell Neurosci ; 2021: 9954302, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34539774

RESUMEN

Neurophysiological studies have shown that there is a close relationship between spikes and local field potential (LFP), which reflects crucial neural coding information. In this paper, we used a new method to evaluate the synchronization between spikes and LFP. All possible phases of LFP from -π to π were first binned into a freely chosen number of bins; then, the probability of spikes falling in each bin was calculated, and the deviation degree from the uniform distribution based on the Kullback-Leibler divergence was calculated to define the synchronization between spikes and LFP. The simulation results demonstrate that the method is rapid, basically unaffected by the total number of spikes, and can adequately resist the noise of spike trains. We applied this method to the experimental data of patients with intractable epilepsy, and we observed the synchronization between spikes and LFP in the formation of memory. These results show that our proposed method is a powerful tool that can quantitatively measure the synchronization between spikes and LFP.


Asunto(s)
Neuronas , Neurofisiología , Potenciales de Acción , Simulación por Computador , Humanos
3.
Medicine (Baltimore) ; 100(14): e25436, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33832147

RESUMEN

BACKGROUND: Hemifacial spasm (HFS) is a clinical common neurological disease, its main performance for 1 side or 2 sides muscles (the orbicularis oculi muscle, expression, orbicularisoris muscles) recurrent paroxysmal, involuntary twitching, aggravating when excited or nervous, more severe cases of the disease may include difficulty in opening the eyes, crooked corners of the mouth, and twitching noises in the ears, etc.[1] Early manifestations of the disease are intermittent mild convulsions of the orbicularis oculi muscle, and then gradually spread to 1 side of the facial muscles, such as frowning muscles, nasal muscles, buccinalis muscles, etc, especially the most obvious spasms of the oral muscles, which can involve the ipsilateral platysma muscle in severe cases, with each twitch for a few seconds to a few minutes. The disease will affect the quality of life such as speaking, eating, seeing and so on, and even cause psychological effects such as inferiority, anxiety and depression. At present, the incidence of the disease in China is 11 per 1.1 million, females are more common than males. There are many ways to treat HFS, but the Qianzheng powder has a unique advantage in treating this disease. Therefore, our systematic review aims to evaluate the efficacy and safety of Qianzheng powder in the treatment of Primary Hemifacial spasm, and to provide a reliable basis for clinical decision makers. METHODS: From its inception until April 2021, we will search electronic databases, including PubMed, Embase, Cochrane Library, China Biomedical Literature Database, China Knowledge Infrastructure, Wanfang Database, and China Scientific Journals Database. The authors will independently sift through studies, extract data information, and assess methodological quality using the Cochrane Risk of Bias tool. The RevManV. 5.3 software will be used for statistical analysis. RESULTS: The results of this study, which will be published in a peerreviewed journal, will evaluate the efficacy and safety of Qianzheng powder in the treatment of primary Hemifacial spasm. CONCLUSION: This systematic review will provide reliable evidence-based basis for treating primary Hemifacial spasm with Qianzheng powder. INPLASY REGISTRATION NUMBER: INPLASY202130037.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Espasmo Hemifacial/tratamiento farmacológico , Toma de Decisiones Clínicas , Protocolos Clínicos , Humanos , Polvos , Resultado del Tratamiento , Metaanálisis como Asunto
4.
Arch Microbiol ; 203(2): 835-846, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33070234

RESUMEN

The yak (Bos grunniens) is a ruminant animal with strong regional adaptability. However, little is known about the adaptation of the rumen microbial community of yaks at different altitudes and the adaptation mechanism of the host and intestinal microorganisms to the habitat. We investigated the adaptability of the rumen microorganisms of yaks at high and low altitudes. We also compared and analyzed the abundance and diversity of core microorganisms and those that varied between different animals. The aim was to compare the rumen bacterial and fungal communities of grazing yak living at two elevations. Bacteroidetes, Firmicutes, Ascomycota, and Chytridiomycota were the dominant bacteria in the plateau and low-altitude regions. Significant differences between the dominant microorganisms in the rumen of yaks were evident in the two regions. The proportion of fiber-degrading bacteria was significantly different between yaks dwelling at high-altitude and low-altitude regions. The abundance of starch-degrading bacteria was not significantly different with altitude. Species clustering similarity analysis showed that the rumen microorganisms in the two areas were obviously isolated and clustered into branches. Functional prediction showed significant differences in rumen microbial methane metabolism, starch and sucrose metabolism, ion-coupled transporter and bacterial secretion system at different altitudes. Overall, the results of this study improved our understanding of the abundance and composition of microorganisms in the rumen of yak at different altitudes.


Asunto(s)
Altitud , Fenómenos Fisiológicos Bacterianos , Bovinos/microbiología , Hongos/fisiología , Rumen/microbiología , Adaptación Fisiológica , Animales , Bacterias/metabolismo , Análisis por Conglomerados , Hongos/aislamiento & purificación , Interacciones Microbiota-Huesped , Metano/metabolismo , Microbiota/fisiología
5.
Braz J Microbiol ; 51(4): 1573-1583, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32949385

RESUMEN

There are many kinds of microorganisms in the gastrointestinal tract of mammals, some of which are closely related to the host. Rumen microorganisms are essential for normal physiological activities of their host by decomposing plant crude lignin and providing essential nutrients. The composition and diversity of this microbial population are influenced by the host, environment, and diet. Despite its importance, little is known about the effects of factors such as altitude variation on rumen microbial population abundance and diversity in different ruminants. Here, we described the changes in overall rumen bacteria in four groups of cattle, including the Zhongdian yellow cattle and Zhongdian yaks, grazing at high altitudes (3600 m); the Jiangcheng yellow cattle and Jiangcheng buffalo were kept at an altitude of 1100 m. We found that there was a significant difference in rumen bacterial abundance of the Zhongdian yellow cattle and Zhongdian yaks at high altitude and there was obvious homogeneity in rumen bacterial abundance and diversity in the Jiangcheng yellow cattle and Jiangcheng buffalo at low altitude. Therefore, our research concluded that under the same dietary environment, there were differences in the abundance and diversity of certain bacteria in the rumen of different breeds of cattle, indicating that host genetic factors and intestinal microorganisms related to altitudinal variation had a greater influence on rumen bacterial abundance in the cattle.


Asunto(s)
Altitud , Alimentación Animal/análisis , Bacterias/clasificación , Microbioma Gastrointestinal , Rumen/microbiología , Animales , Bovinos , Filogenia
6.
J Geriatr Cardiol ; 16(3): 298-306, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31080473

RESUMEN

OBJECTIVES: To assess and synthesize the prospective cohort studies published so far on the association between atrial fibrillation (AF) and dementia incidence. METHODS: We searched PubMed, Web of Science, and the Cochrane Library for potential studies published in English previous to April 2018. Two independent reviewers screened the search results for prospective cohort studies reporting the association between AF and dementia incidence in patients with normal cognitive function at baseline and not suffering from an acute stroke. The Newcastle-Ottawa Scale was adopted to evaluate the quality of the included studies. The pooled hazard ratio (HR) of AF for dementia was calculated with the Comprehensive Meta-Analysis software, version 2. Heterogeneity and publication bias were assessed with the I 2 test and funnel plot, respectively. RESULTS: We finally identified 11 prospective cohort studies covering 112,876 patients. All the included studies reported an adjusted HR obtained in multiple Cox regression models. The qualities of the included studies ranged from moderate to high. In pooled analysis with a fixed-effects model, AF was independently associated with dementia incidence (HR = 1.34, 95% CI: 1.24-1.44). Subgroup analysis of studies considering anticoagulation as an important confounding factor achieved a similar result. Based on the I 2 test and funnel plot, we did not detect obvious heterogeneity and publication bias in our study. Meta-regression on age did not find significant results. CONCLUSIONS: The results of our meta-analysis further confirmed that AF was an independent risk factor for dementia in patients with normal baseline cognitive function not suffering from acute stroke. Screening for dementia in AF patients and including dementia as an independent outcome in large AF treatment trials is warranted.

7.
8.
Genetica ; 135(3): 419-27, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18604631

RESUMEN

The cushion rockjasmine, Androsace tapete (Primulaceae), is among the angiosperms with highest altitudal distribution in the world. Cushion rockjasmine is a prominent pioneer species in alpine deserts and alpine flowstone slope habitats up to 5,300 m on Qinghai-Tibetan Plateau. In this study, we use inter simple sequence repeat (ISSR) markers to investigate the spatial genetic structure of A. tapete at both fine-scale and landscape-scale, with emphasis on testing the hypothesis that the low-altitude valley of the Brahmaputra River, running from west to east across Qinghai-Tibetan Plateau, has significant effects on the spatial population structure of A. tapete. A total of 235 individuals were collected from five populations in disjunct ridges (i.e. two populations located in the north, and three in the south of the Brahmaputra River), including 158 individuals that were spatial explicitly sampled from a 30 m x 90 m plot. At fine scale, spatial autocorrelation analysis indicates a significant genetic structure within a short distance (less than 10 m), which is probably due to limited gene dispersal via pollen and/or seeds. At landscape scale, however, AMOVA suggests that most of the total genetic variation (85%) is among individuals within populations; and the Brahmaputra River plays a weak role in shaping the spatial population structure of A. tapete. In addition, the results of PCA and STRUCTURE assignment show significant genetic associations between the populations across the Brahmaputra River. The historical gene exchanges and slow genetic drift may be responsible for the lack of deep genetic differentiation among topographically separated populations in A. tapete.


Asunto(s)
Variación Genética , Primulaceae/genética , Flujo Genético , Estructuras Genéticas , Genética de Población , Geografía , Primulaceae/clasificación , Tibet
10.
Curr Opin Pharmacol ; 5(5): 520-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16087397

RESUMEN

During the past decade, nucleotide analogs have emerged as novel antiviral agents against hepatitis B virus. Adefovir dipivoxil, a prototype phosphonate analog, has been approved for chronic hepatitis B virus therapy, and additional phosphonate analogs and di- and tri-nucleotides are under development. Several innovative prodrug derivatizations have also been reported to improve the oral bioavailability of nucleotide analogs, which usually carry a negative charge.


Asunto(s)
Antivirales/farmacología , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Nucleótidos/farmacología , Antivirales/química , Antivirales/metabolismo , Antivirales/uso terapéutico , Humanos , Nucleótidos/química , Nucleótidos/metabolismo , Nucleótidos/uso terapéutico , Profármacos/química , Profármacos/metabolismo
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