Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 481
Filtrar
1.
Gastroenterology ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38582270

RESUMO

BACKGROUND & AIMS: Hepatitis E virus (HEV), primarily genotype 1 (HEV-1), causes approximately 20.1 million infections, 44,000 deaths, and 3000 stillbirths annually. Current evidence indicates that HEV-1 is only transmitted in humans. Here, we evaluated whether Mongolian gerbils can serve as animal models for HEV-1 infection. METHODS: Mongolian gerbils were used for HEV-1 and hepatitis E virus genotype 3 infection experiments. HEV infection parameters, including detection of HEV RNA and HEV antigen, liver function assessment, and histopathology, were evaluated. RESULTS: We adapted a clinical isolate of HEV-1 for Mongolian gerbils by serial passaging in feces of aged male gerbils. The gerbil-adapted strain obtained at passage 3 induced a robust, acute HEV infection, characterized by stable fecal virus shedding, elevated liver enzymes, histopathologic changes in the liver, and seroconversion to anti-HEV. An infectious complementary DNA clone of the adapted virus was generated. HEV-1-infected pregnant gerbils showed a high rate of maternal mortality and vertical transmission. HEV RNA or antigens were detected in the liver, kidney, intestine, placenta, testis, and fetus liver. Liver and placental transcriptomic analyses indicated activation of host immunity. Tacrolimus prolonged HEV-1 infection, whereas ribavirin cleared infection. The protective efficacy of a licensed HEV vaccine was validated using this model. CONCLUSIONS: HEV-1 efficiently infected Mongolian gerbils. This HEV-1 infection model will be valuable for investigating hepatitis E immunopathogenesis and evaluating vaccines and antivirals against HEV.

2.
Genomics ; 116(3): 110844, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38608737

RESUMO

The study demonstrated that melatonin (MT) can induce the development of secondary hair follicles in Inner Mongolian cashmere goats through the Wnt10b gene, leading to secondary dehairing. However, the mechanisms underlying the expression and molecular function of Wnt10b in dermal papilla cells (DPC) remain unknown. This research aimed to investigate the impact of MT on DPC and the regulation of Wnt10b expression, function, and molecular mechanisms in DPC. The findings revealed that MT promotes DPC proliferation and enhances DPC activity. Co-culturing DPC with overexpressed Wnt10b and MT showed a significant growth promotion. Subsequent RNA sequencing (RNA-seq) of overexpressed Wnt10b and control groups unveiled the regulatory role of Wnt10b in DPC. Numerous genes and pathways, including developmental pathways such as Wnt and MAPK, as well as processes like hair follicle morphogenesis and hair cycle, were identified. These results suggest that Wnt10b promotes the growth of secondary hair follicles in Inner Mongolian cashmere goats by regulating crucial factors and pathways in DPC proliferation.


Assuntos
Proliferação de Células , Cabras , Folículo Piloso , Melatonina , Proteínas Wnt , Animais , Folículo Piloso/metabolismo , Folículo Piloso/citologia , Folículo Piloso/crescimento & desenvolvimento , Cabras/genética , Cabras/metabolismo , Melatonina/farmacologia , Melatonina/metabolismo , Proteínas Wnt/metabolismo , Proteínas Wnt/genética , Células Cultivadas
3.
Microb Pathog ; 188: 106566, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309310

RESUMO

Similar to gut bacterial community, gut fungal community are also an important part of the gut microbiota and play crucial roles in host immune regulation and metabolism. However, most studies have focused on the gut bacterial community, and research on the gut fungal community has been limited. Dutch Warmblood (DWH) and Mongolian horses (MGH) are important equine breeds, but little research has been done on their gut fungal community. Here, we assessed differences in gut fungal community between two horse species. Results showed that a total of 2159 OTUs were found in the Dutch Warmblood and Mongolian horses, of which 308 were common. Between-group analyzes of microbial diversity showed no differences in the alpha and beta diversity of gut fungal community between the two horse species. Microbiological taxonomic surveys showed that the dominant fungal phyla (Neocallimastigomycota and Ascomycota) and genera (unclassified_Neocallimastigaceae and Anaeromyces) were the same without being affected by species. Although the types of dominant fungal phyla did not change, the abundances of some fungal genera changed significantly. Results of Metastats analysis showed that there were a total of 206 fungal genera that were significantly different between the two horses, among which 78 genera showed an increase and 127 genera significantly decreased in Dutch Warmblood horses compared with Mongolian horses. In conclusion, this study investigated the composition and structure of the gut fungal community of Dutch Warmblood and Mongolian horses and found significant differences in gut fungal community between both breeds. Notably, this is the first exploration of the differences in the gut fungal community of both breeds, which may help to understand the distribution characteristics of the gut fungal community of different breeds of horses and reveal the differences in the traits of different horses.


Assuntos
Microbioma Gastrointestinal , Microbiota , Micobioma , Humanos , Animais , Cavalos , Melhoramento Vegetal , Microbioma Gastrointestinal/genética , Etnicidade , Bactérias
4.
Curr Top Microbiol Immunol ; 444: 25-52, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38231214

RESUMO

The human pathogen Helicobacter pylori is the strongest known risk factor for gastric disease and cancer, and gastric cancer remains a leading cause of cancer-related death across the globe. Carcinogenic mechanisms associated with H. pylori are multifactorial and are driven by bacterial virulence constituents, host immune responses, environmental factors such as iron and salt, and the microbiota. Infection with strains that harbor the cytotoxin-associated genes (cag) pathogenicity island, which encodes a type IV secretion system (T4SS) confer increased risk for developing more severe gastric diseases. Other important H. pylori virulence factors that augment disease progression include vacuolating cytotoxin A (VacA), specifically type s1m1 vacA alleles, serine protease HtrA, and the outer-membrane adhesins HopQ, BabA, SabA and OipA. Additional risk factors for gastric cancer include dietary factors such as diets that are high in salt or low in iron, H. pylori-induced perturbations of the gastric microbiome, host genetic polymorphisms, and infection with Epstein-Barr virus. This chapter discusses in detail host factors and how H. pylori virulence factors augment the risk of developing gastric cancer in human patients as well as how the Mongolian gerbil model has been used to define mechanisms of H. pylori-induced inflammation and cancer.


Assuntos
Infecções por Vírus Epstein-Barr , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Herpesvirus Humano 4 , Citotoxinas , Helicobacter pylori/genética , Ferro , Fatores de Virulência/genética
5.
Glob Chang Biol ; 30(1): e17002, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37916481

RESUMO

The migration of trees induced by climatic warming has been observed at many alpine treelines and boreal-tundra ecotones, but the migration of temperate trees into southern boreal forest remains less well documented. We conducted a field investigation across an ecotone of temperate and boreal forests in northern Greater Khingan Mountains of northeast China. Our analysis demonstrates that Mongolian oak (Quercus mongolica), an important temperate tree species, has migrated rapidly into southern boreal forest in synchrony with significant climatic warming over the past century. The average rate of migration is estimated to be 12.0 ± 1.0 km decade-1 , being slightly slower than the movement of isotherms (14.7 ± 6.4 km decade-1 ). The migration rate of Mongolian oak is the highest observed among migratory temperate trees (average rate 4.0 ± 1.0 km decade-1 ) and significantly higher than the rates of tree migration at boreal-tundra ecotones (0.9 ± 0.4 km decade-1 ) and alpine treelines (0.004 ± 0.003 km decade-1 ). Compared with the coexisting dominant boreal tree species, Dahurian larch (Larix gmelinii), temperate Mongolian oak is observed to have significantly lower capacity for light acquisition, comparable water-use efficiency but stronger capacity to utilize nutrients especially the most limiting nutrient, nitrogen. In the context of climatic warming, and in addition to a high seed dispersal capacity and potential thermal niche differences, the advantage of nutrient utilization, reflected by foliar elementomes and stable nitrogen isotope ratios, is also likely a key mechanism for Mongolian oak to coexist with Dahurian larch and facilitate its migration toward boreal forest. These findings highlight a rapid deborealization of southern Asian boreal forest in response to climatic warming.


Assuntos
Larix , Quercus , Taiga , Árvores/fisiologia , Tundra , Nitrogênio , Larix/fisiologia , Florestas
6.
Int J Legal Med ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822837

RESUMO

The assessment of skin changes in the context of possible child abuse is an important task in forensic medicine. This requires knowledge of pigmentation variants and pigmentation disorders such as congenital dermal melanocytosis, which includes Mongolian spots. Particularly in the case of atypical localization and dark pigmented skin, the differentiation from hematomas can be challenging. A case of two Nigerian siblings with extensive and atypically localized Mongolian spots is reported. The 1.5-year-old girl showed Mongolian spots on her back and the right side of her trunk. The 8-year-old boy showed Mongolian spots only on the back of his thighs. The authors are not aware of any case in which so called Mongolian spots were present exclusively on the back of the thighs and this case is all the more noteworthy as the back of the thigh is a common localization of blunt force trauma.

7.
Gastric Cancer ; 27(2): 324-342, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310631

RESUMO

Helicobacter pylori (H. pylori, Hp) has been designated a class I carcinogen and is closely associated with severe gastric diseases. During colonization in the gastric mucosa, H. pylori develops immune escape by inducing host immune tolerance. The gastric epithelium acts as the first line of defense against H. pylori, with Toll-like receptors (TLRs) in gastric epithelial cells being sensitive to H. pylori components and subsequently activating the innate immune system. However, the mechanism of immune tolerance induced by H. pylori through the TLR signalling pathway has not been fully elucidated. In this research, we detected the expression of TLRs and inflammatory cytokines in GES-1 cells upon sustained exposure to H. pylori or H. pylori lysate from 1 to 30 generations and in Mongolian gerbils infected with H. pylori for 5 to 90 weeks. We found that the levels of TLR6 and inflammatory cytokines first increased and then dropped during the course of H. pylori treatment in vitro and in vivo. The restoration of TLR6 potentiated the expression of IL-1ß and IL-8 in GES-1 cells, which recruited neutrophils and reduced the colonization of H. pylori in the gastric mucosa of gerbils. Mechanistically, we found that persistent infection with H. pylori reduces the sensitivity of TLR6 to bacterial components and regulates the expression of inflammatory cytokines in GES-1 cells through TLR6/JNK signaling. The TLR6 agonist obviously alleviated inflammation in vitro and in vivo. Promising results suggest that TLR6 may be a potential candidate immunotherapy drug for H. pylori infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Animais , Humanos , Receptor 6 Toll-Like/metabolismo , Gerbillinae , Neoplasias Gástricas/metabolismo , Citocinas/metabolismo , Infecções por Helicobacter/complicações , Mucosa Gástrica/metabolismo
8.
J Pharmacol Sci ; 155(2): 29-34, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677783

RESUMO

Microglia are the residential immune cells in the central nervous system. Their roles as innate immune cells and regulators of synaptic remodeling are critical to the development and the maintenance of the brain. Numerous studies have depleted microglia to elucidate their involvement in healthy and pathological conditions. PLX3397, a blocker of colony stimulating factor 1 receptor (CSF1R), is widely used to deplete mouse microglia due to its non-invasiveness and convenience. Recently, other small rodents, including Syrian hamsters (Mesocricetus auratus) and Mongolian gerbils (Meriones unguiculatus), have been recognized as valuable animal models for studying brain functions and diseases. However, whether microglia depletion via PLX3397 is feasible in these species remains unclear. Here, we administered PLX3397 orally via food pellets to hamsters and gerbils. PLX3397 successfully depleted gerbil microglia but had no effect on microglial density in hamsters. Comparative analysis of the CSF1R amino acid sequence in different species hints that amino acid substitutions in the juxtamembrane domain may potentially contribute to the inefficacy of PLX3397 in hamsters.


Assuntos
Aminopiridinas , Encéfalo , Gerbillinae , Microglia , Pirróis , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos , Animais , Cricetinae , Administração Oral , Aminopiridinas/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/citologia , Mesocricetus , Microglia/efeitos dos fármacos , Microglia/metabolismo , Modelos Animais , Pirróis/farmacologia , Pirrolidinas/farmacologia , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Especificidade da Espécie
9.
J Appl Microbiol ; 135(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39020259

RESUMO

AIMS: Pulmonary fibrosis (PF) is a progressive and incurable lung disease for which treatment options are limited. Here, we aimed to conduct an exploratory study on the effects of the Mongolian medicine Saorilao-4 (SRL) on the gut microbiota structure, species abundance, and diversity of a rat PF model as well as the mechanisms underlying such effects. METHODS AND RESULTS: Rat fecal samples were analyzed using 16S rRNA sequencing technology. Bioinformatic and correlation analyses were performed on microbiota data to determine significant associations. SRL substantially attenuated the adverse effects exerted by PF on the structure and diversity of gut microbiota while regulating its alpha and beta diversities. Linear discriminant analysis effect size enabled the identification of 62 differentially abundant microbial taxa. Gut microbiota abundance analysis revealed that SRL significantly increased the relative abundance of bacterial phyla such as Firmicutes and Bacteroidetes. Moreover, SRL increased the proportion of beneficial bacteria, such as Lactobacillus and Bifidobacteriales, decreased the proportion of pathogenic bacteria, such as Rikenellaceae, and balanced the gut microbiota by regulating metabolic pathways. CONCLUSIONS: SRL may attenuate PF by regulating gut microbiota. This exploratory study establishes the groundwork for investigating the metagenomics of PF.


Assuntos
Bactérias , Modelos Animais de Doenças , Fezes , Microbioma Gastrointestinal , Fibrose Pulmonar , RNA Ribossômico 16S , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , RNA Ribossômico 16S/genética , Ratos , Fibrose Pulmonar/microbiologia , Fibrose Pulmonar/genética , Fezes/microbiologia , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Masculino , Ratos Sprague-Dawley
10.
Cryobiology ; 114: 104791, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37956782

RESUMO

Mongolian sheep are a breed of sheep in China known for their excellent cold and drought resistance. Sperm from Mongolian sheep are often cryopreserved to improve breeding outcomes. However, cryopreservation of sperm often results in issues such as reduced vitality and altered morphology. Therefore, the objective of this study was to investigate the impact of the cryoprotectant resveratrol on frozen sperm from Mongolian sheep, specifically examining its effects on key proteins during cryopreservation. In this study, sperm samples were obtained from three adult Mongolian rams and processed through semen centrifugation. The sperm motility parameters of Fresh Sperm Group (FR), Resveratrol added before freezing group (FF-Res), Resveratrol-free frozen sperm group (FT), and Resveratrol added after freeze-thawing group (FA-Res) were determined. The tandem mass tags (TMT) peptide labeling combined with LC-MS/MS was used for proteomic analysis of the total proteins in FR and FT groups. A total of 2651 proteins were identified, among which 41 proteins were upregulated and 48 proteins were downregulated after freezing. In-depth bioinformatics analysis of differentially abundant proteins (DAPs) revealed their close association with the tricarboxylic acid cycle (TCA) and oxidative phosphorylation pathway. The energy-related protein dihydrolipoamide dehydrogenase (DLD) and the reactive oxygen species (ROS)-related protein NADH dehydrogenase 1 beta subcomplex subunit 9 (NDUFB9) exhibited significant decreases, indicating their potential role as key proteins contributing to reduced sperm vitality. The study demonstrated that the addition of resveratrol (RES) to semen could elevate the expression levels of DLD and NDUFB9 proteins. This study represents the pioneering proteomic analysis of Mongolian ram sperm before and after cryopreservation, establishing the significance of DLD and NDUFB9 as key proteins influencing the decline in vitality following cryopreservation of Mongolian ram sperm. These findings clarify that resveratrol can enhance the levels of DLD and NDUFB9 proteins in cryopreserved Mongolian ram sperm, consequently enhancing their vitality.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Ovinos , Animais , Resveratrol/farmacologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Di-Hidrolipoamida Desidrogenase/farmacologia , Criopreservação/métodos , Proteômica , Cromatografia Líquida , Motilidade dos Espermatozoides , Espectrometria de Massas em Tandem , Espermatozoides , Carneiro Doméstico
11.
J Asian Nat Prod Res ; : 1-15, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037411

RESUMO

Zhachong-13 pills (ZC-13), as a traditional prescription of Mongolian medicine, are often used in the clinical practice of Mongolian hospitals for the treatment of stroke and rheumatic arthritis. In this experiment, UHPLC-Q-Exactive Orbitrap MS was used to explore the chemical composition of ZC-13. The results showed that 315 compounds were identified or inferred, including 56 alkaloids, 77 2-(2-phenylethyl)chromones, 61 flavonoids, 31 tannins, 8 coumarins, 16 lignans, 21 terpenoids, 5 amino acids, 19 organic acids, and 21 other components. In addition, the pharmacological activities related to anti-cerebral ischemia of these components were summarized. This result laid a foundation for further study on the pharmacodynamic material basis of ZC-13 and provided a scientific basis for the formulation of ZC-13 quality specifications.

12.
J Environ Manage ; 355: 120365, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38460328

RESUMO

Land use/land cover (LULC) change and climate change are interconnected factors that affect the ecological environment. However, there is a lack of quantification of the impacts of LULC change and climate change on landscape ecological risk under different shared socioeconomic pathways and representative concentration pathways (SSP-RCP) on the Mongolian Plateau (MP). To fill this knowledge gap and understand the current and future challenges facing the MP's land ecological system, we conducted an evaluation and prediction of the effects of LULC change and climate change on landscape ecological risk using the landscape loss index model and random forest method, considering eight SSP-RCP coupling scenarios. Firstly, we selected MCD12Q1 as the optimal LULC product for studying landscape changes on the MP, comparing it with four other LULC products. We analyzed the diverging patterns of LULC change over the past two decades and observed significant differences between Mongolia and Inner Mongolia. The latter experienced more intense and extensive LULC change during this period, despite similar climate changes. Secondly, we assessed changes in landscape ecological risk and identified the main drivers of these changes over the past two decades using a landscape index model and random forest method. The highest-risk zone has gradually expanded, with a 30% increase compared to 2001. Lastly, we investigated different characteristics of LULC change under different scenarios by examining future LULC products simulated by the FLUS model. We also simulated the dynamics of landscape ecological risks under these scenarios and proposed an adaptive development strategy to promote sustainable development in the MP. In terms of the impact of climate change on landscape ecological risk, we found that under the same SSP scenario, increasing RCP emission concentrations significantly increased the areas with high landscape ecological risk while decreasing areas with low risk. By integrating quantitative assessments and scenario-based modeling, our study provides valuable insights for informing sustainable land management and policy decisions in the region.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , Ecossistema , Desenvolvimento Sustentável , Previsões
13.
Nurs Philos ; 25(1): e12469, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37933776

RESUMO

Mongolian philosophical underpinnings of well-being were expressed in the form of mythology, shamanism and Mongolian Buddhism before the development of modern nursing in Mongolia. Among these forms, the philosophical underpinnings of well-being, mythology and shamanism were formed as a result of the roots of Mongolian philosophy, whereas Buddhism spread relatively late. As a result of Mongolian mythology, an alternative approach called dom zasal was formed, and it remains one of the important foundations of the idea of well-being among people. Among the various concepts of shamanism, the concept of sunesu best expresses the underpinning of well-being, and the idea that healing and nursing care can be provided not only by those living in this world but also by spirit beings. Since Mongolians still use these ideas even in modern times, it should be noted that following them too narrowly may conflict with concepts based on scientific evidence. Along with the development of Buddhist philosophy in Mongolia, the Oriental philosophical underpinnings of well-being have spread. One of the most important concepts is the five basic elements of life (tavan mahabhutas) and three elements of the body (khii, shar and badgan). While developing the concepts of life and the body, the arga-bileg model (yin-yang in Chinese), developed at the theoretical level in Chinese philosophy, has become a popular basis for culture and customs among Mongolians. Therefore, it has been difficult to judge whether the origin of the arga-bileg model is Mongolian or Chinese; however, this is undeniably an important underpinning for well-being in both countries.


Assuntos
Cuidados de Enfermagem , Xamanismo , Humanos , Mitologia , Budismo , Filosofia
14.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2991-3001, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-39041159

RESUMO

Neuropathic pain(NP) is difficult to be treated since it has similar phenotypes but different pathogenesis in different pathological stages. Targeted intervention of the core regulatory elements at different pathological stages of NP has become a new direction of drug research and development in recent years and provides the possibility for the treatment of NP. The Mongolian medicine Naru-3(NR-3) is effective in the treatment of sciatica and trigeminal neuralgia, the mechanisms of which remain unknown. On the basis of the previous study of the priming stage, this study established the mouse model of spinal nerve ligation(SNL) and measured the changes of pain thresholds by behavioral tests. The network analysis, Western blot, immunofluorescence assay, ELISA, and agonist/antagonist were employed to decipher the mechanism of NR-3 in the treatment of NP in the maintenance stage. The results showed that NR-3 increased the mechanical and thermal pain thresholds of SNL mice, while it had no significant effect on the basal pain threshold of normal mice. NR-3 may relieve the pain in the maintenance stage of NP by blocking the matrix metalloproteinase 2(MMP2)/interleukin-1ß(IL-1ß) pathway in the astrocytes of the dorsal root ganglion(DRG) and spinal cord. The findings have enriched the biological connotation of NR-3 in the treatment of the maintenance stage of NP and provide reference for the rational use of this medicine in clinical practice.


Assuntos
Astrócitos , Medicina Tradicional da Mongólia , Neuralgia , Animais , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Camundongos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Masculino , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Doenças Neuroinflamatórias/tratamento farmacológico , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Modelos Animais de Doenças
15.
J Neurosci ; 42(10): 2025-2038, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35064004

RESUMO

Functional hemispheric lateralization is a basic principle of brain organization. In the auditory domain, the right auditory cortex (AC) determines the pitch direction of continuous auditory stimuli whereas the left AC discriminates gaps in these stimuli. The involved functional interactions between the two sides, mediated by commissural connections, are poorly understood. Here, we selectively disrupted the interhemispheric cross talk from the left to the right primary AC and vice versa using chromophore-targeted laser-induced apoptosis of the respective projection neurons, which make up 6-17% of all AC neurons in Layers III, V, and VI. Following photolysis, male gerbils were trained in a first experimental set to discriminate between rising and falling frequency-modulated (FM) tone sweeps. The acquisition of the task was significantly delayed in lesioned animals of either lesion direction. However, the final discrimination performance and hit rate was lowest for animals with left-side lesioned commissural neurons, demonstrating that also information from the left AC is relevant for FM direction learning. Photolysis after successful learning did not affect the retrieval of the learned task, indicating that the disruption during learning was not because of a general functional impairment. In a second experimental set, the gerbil's ability to detect and discriminate small silent gaps of varying length within FM sweeps was tested. This ability was also preserved after interhemispheric disruption. Taken together, interhemispheric communication between the left and right AC is important for the acquisition of FM tone direction learning but not for its retrieval and for gap detection and gap duration discrimination.SIGNIFICANCE STATEMENT Hemispheric lateralization of neuronal functions such as speech and music processing in humans are common throughout the brain; however, the involved interhemispheric interactions are ill-defined. Here, we show that the selective photolytic disruption of auditory cortical commissural connections in rodents impairs the acquisition but not retrieval of a frequency-modulated tone direction discrimination task. The final discrimination performance and hit rate was lowest for animals with lesioned left-to-right-side projections; thus, although right auditory cortex is dominant, left auditory cortex is also relevant for learning this task. The detection and discrimination of small gaps within the tone sweeps remain intact, suggesting a pathway for the processing of these temporal structures, which could be independent from the lesioned interhemispheric cross talk.


Assuntos
Córtex Auditivo , Aprendizagem por Discriminação , Estimulação Acústica , Animais , Córtex Auditivo/fisiologia , Aprendizagem por Discriminação/fisiologia , Gerbillinae/fisiologia , Masculino , Discriminação da Altura Tonal
16.
BMC Genomics ; 24(1): 35, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658473

RESUMO

BACKGROUND: Thousands of years of natural and artificial selection since the domestication of the horse has shaped the distinctive genomes of Chinese Mongolian horse populations. Consequently, genomic signatures of selection can provide insights into the human-mediated selection history of specific traits and evolutionary adaptation to diverse environments. Here, we used genome-wide SNPs from five distinct Chinese Mongolian horse populations to identify genomic regions under selection for the population-specific traits, gait, black coat colour, and hoof quality. Other global breeds were used to identify regional-specific signatures of selection. RESULTS: We first identified the most significant selection peak for the Wushen horse in the region on ECA23 harbouring DMRT3, the major gene for gait. We detected selection signatures encompassing several genes in the Baicha Iron Hoof horse that represent good biological candidates for hoof health, including the CSPG4, PEAK1, EXPH5, WWP2 and HAS3 genes. In addition, an analysis of regional subgroups (Asian compared to European) identified a single locus on ECA3 containing the ZFPM1 gene that is a marker of selection for the major domestication event leading to the DOM2 horse clade. CONCLUSIONS: Genomic variation at these loci in the Baicha Iron Hoof may be leveraged in other horse populations to identify animals with superior hoof health or those at risk of hoof-related pathologies. The overlap between the selection signature in Asian horses with the DOM2 selection peak raises questions about the nature of horse domestication events, which may have involved a prehistoric clade other than DOM2 that has not yet been identified.


Assuntos
Casco e Garras , Cavalos , Animais , Proteínas Adaptadoras de Transdução de Sinal/genética , Genoma , Cavalos/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Seleção Genética , Ubiquitina-Proteína Ligases/genética , Adaptação Biológica/genética
17.
Ecol Lett ; 26(6): 858-868, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36922741

RESUMO

Understanding the effects of diversity on ecosystem stability in the context of global change has become an important goal of recent ecological research. However, the effects of diversity at multiple scales and trophic levels on ecosystem stability across environmental gradients remain unclear. Here, we conducted a field survey of α-, ß-, and γ-diversity of plants and soil biota (bacteria, fungi, and nematodes) and estimated the temporal ecosystem stability of normalized difference vegetation index (NDVI) in 132 plots on the Mongolian Plateau. After climate and soil environmental variables were controlled for, both the α- and ß-diversity of plants and soil biota (mainly via nematodes) together with precipitation explained most variation in ecosystem stability. These findings evidence that the diversity of both soil biota and plants contributes to ecosystem stability. Model predictions of the future effects of global changes on terrestrial ecosystem stability will require field observations of diversity of both plants and soil biota.


Assuntos
Ecossistema , Pradaria , Solo , Biota , Plantas
18.
J Neurophysiol ; 130(3): 736-750, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37584075

RESUMO

The spiking activity of auditory nerve fibers (ANFs) transmits information about the acoustic environment from the cochlea to the central auditory system. Increasing age leads to degeneration of cochlear tissues, including the sensory hair cells and stria vascularis. Here, we aim to identify the functional effects of such age-related cochlear pathologies of ANFs. Rate-level functions (RLFs) were recorded from single-unit ANFs of young adult (n = 52, 3-12 months) and quiet-aged (n = 24, >36 months) Mongolian gerbils of either sex. RLFs were used to determine sensitivity and spontaneous rates (SRs) and were classified into flat-saturating, sloping-saturating, and straight categories, as previously established. A physiologically based cochlear model, adapted for the gerbil, was used to simulate the effects of cochlear degeneration on ANF physiology. In ANFs tuned to low frequencies (<3.5 kHz), SR was lower in those of aged gerbils, while an age-related loss of low-SR fibers was evident in ANFs tuned to high frequencies. These changes in SR distribution did not affect the typical SR versus sensitivity correlation. The distribution of RLF types among low-SR fibers, however, shifted toward that of high-SR fibers, specifically showing more fast-saturating and fewer sloping-saturating RLFs. A modeled striatal degeneration, which affects the combined inner hair cell and synaptic output, reduced SR but left RLF type unchanged. An additional reduced basilar membrane gain, which decreased sensitivity, explained the changed RLF types. Overall, the data indicated age-related changes in the characteristics of single ANFs that blurred the established relationships between SR and RLF types.NEW & NOTEWORTHY Auditory nerve fibers, which connect the cochlea to the central auditory system, change their encoding of sound level in aged gerbils. In addition to a general shift to higher levels, indicative of decreased sensitivity, level coding was also differentially affected in fibers with low- and high-spontaneous rates. Loss of low-spontaneous rate fibers, combined with a general decrease of spontaneous rate, further blurs the categorization of auditory nerve fiber types in the aged gerbil.


Assuntos
Cóclea , Nervo Coclear , Animais , Gerbillinae , Cóclea/fisiologia , Nervo Coclear/fisiologia , Envelhecimento/fisiologia , Fibras Nervosas/fisiologia , Estimulação Acústica
19.
BMC Microbiol ; 23(1): 253, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689675

RESUMO

BACKGROUND: Anaerobic fungi are effective fibre-degrading microorganisms in the digestive tract of horses. However, our understanding of their diversity and community structure is limited, especially in different parts of the gastrointestinal tract. RESULTS: For the first time, high-throughput sequencing technology was used to analyse and predict fungal microbial diversity in different parts of the gastrointestinal tract of Mongolian horses. The results revealed that the richness and diversity of fungi in the hindgut of Mongolian horses were much higher than those in the foregut. The foregut was dominated by Basidiomycota and Ascomycota, whereas the hindgut was dominated by Neocallimastigomycota and Basidiomycota. At the genus level, the relative abundance of many pathogenic fungi (Cryptococcus, Cladosporium, Alternaria, and Sarocladium) in the foregut was significantly higher than that in the posterior gut, indicating that Mongolian horses have strong disease resistance. The prediction of fungal function also showed significant differences in the fungal flora between the foregut and the hindgut. The fungi in Mongolian horses' foreguts were mainly pathologically nutritive and contained many animal and plant pathogens, particularly in the small intestine (jejunum and ileum). This indicates that the foregut may be the most important immune site in the digestive system of Mongolian horses, which explains the high disease resistance of Mongolian horses. The number of unassigned functional groups in the posterior gut was significantly higher than that in the anterior gut, indicating that the functions of fungal groups in the posterior gut have not been fully explored, and further studies are required in the future. CONCLUSIONS: Analysis of high-throughput sequencing results revealed that the fungal composition varied greatly among different gastrointestinal tract segments in Mongolian horses, whose hindgut contains many anaerobic fungi involved in plant cellulose degradation. This provides important basic data for studying fungal diversity in the digestive system of healthy horses, which can be used for the health assessment of horses and provides clues for further research on the disease resistance and digestive capacity of horses, as well as a reference for the early diagnosis of intestinal diseases and innovative treatment methods.


Assuntos
Micobioma , Cavalos , Animais , Resistência à Doença , Íleo , Jejuno , Digestão
20.
BMC Microbiol ; 23(1): 102, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060052

RESUMO

BACKGROUND: Many studies reported the association between gut microbiota and type 2 diabetes mellitus (T2D), but it is still unclear which bacterial genus plays a key role and how the metabolic function of gut microbiota changes in the occurrence and development of T2D. Besides, there is a high diabetic prevalence in Mongolian population, which may be partly affected by their high calorie diet. This study identified the main bacterial genus influencing T2D in Mongolian population, and analyzed the changes of metabolic function of gut microbiome. The association between dietary factors and the relative abundance of main bacterial genus and its metabolic function was also studied. METHODS: Dietary surveys and gut microbiota test were performed on 24 Mongolian volunteers that were divided into T2D (6 cases), PRET2D (6 cases) and Control group (12 cases) according to fasting plasma glucose (FPG) values. The relative abundance and metabolic function of gut microbiome from their fecal samples were measured by metagenomic analysis. Statistic method was used to evaluate the association between dietary factors and the relative abundance of the main bacterial genus or its metabolic function. RESULTS: This study found that the Clostridium genus may be one of the key bacterial genera affecting the process of T2D. First, the relative abundance of Clostridium genus was significantly different among the three groups. Second, there was a higher relative abundance of metabolic enzymes of gut bacteria in PRET2D and T2D group than that in Control group. Third, a strong correlation between Clostridium genus and many metabolic enzymes was uncovered, many of which may be produced by the Clostridium. Last, carotene intake daily was negatively correlated with the Clostridium but positively correlated with tagaturonate reductase catalyzing interconversions of pentose and glucuronate. CONCLUSIONS: The gut Clostridium genus may play an important role in the development of T2D and it could be a potential biomarker for T2D in Mongolian population. Meanwhile, the metabolic function of gut bacteria has changed during the early stage of T2D and the changes in carbohydrate, amino acid, lipid or energy metabolism of Clostridium genus may play a critical role. In addition, the carotene intake may affect reproduction and metabolic function of Clostridium genus.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Glicemia , Dieta , Bactérias/genética , Jejum
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA