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1.
J Agric Food Chem ; 72(25): 14165-14176, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38872428

RESUMO

Atractylodes macrocephala Koidz, a traditional Chinese medicine, contains atractylenolide I (ATR-I), which has potential anticancer, anti-inflammatory, and immune-modulating properties. This study evaluated the therapeutic potential of ATR-I for indomethacin (IND)-induced gastric mucosal lesions and its underlying mechanisms. Noticeable improvements were observed in the histological morphology and ultrastructures of the rat gastric mucosa after ATR-I treatment. There was improved blood flow, a significant decrease in the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1ß, and IL-18, and a marked increase in prostaglandin E2 (PGE2) expression in ATR-I-treated rats. Furthermore, there was a significant decrease in the mRNA and protein expression levels of NOD-like receptor thermal protein domain associated protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC), cysteinyl aspartate specific proteinase-1 (caspase-1), and nuclear factor-κB (NF-κB) in rats treated with ATR-I. The results show that ATR-I inhibits the NLRP3 inflammasome signaling pathway and effectively alleviates local inflammation, thereby improving the therapeutic outcomes against IND-induced gastric ulcers in rats.


Assuntos
Atractylodes , Mucosa Gástrica , Indometacina , Inflamassomos , Lactonas , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos Sprague-Dawley , Sesquiterpenos , Úlcera Gástrica , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Indometacina/efeitos adversos , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/metabolismo , Ratos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Lactonas/farmacologia , Lactonas/química , Inflamassomos/metabolismo , Inflamassomos/genética , Inflamassomos/efeitos dos fármacos , Masculino , Atractylodes/química , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , NF-kappa B/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-1beta/imunologia , Caspase 1/genética , Caspase 1/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-6/imunologia , Interleucina-18/genética , Interleucina-18/metabolismo
2.
Heliyon ; 10(10): e31620, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38831806

RESUMO

Background: Oxidative stress plays a significant role in the pathogenesis of many retinal diseases. However, only a few systematic bibliometric studies have been conducted. This study aims to visualize research hotspots and developmental trends in oxidative stress in the retina from 2013 to 2023 by analyzing bibliometric data. Methods: We retrieved papers on oxidative stress in the retina published between 2013 and 2023 from the Web of Science Core Collection. The data were visually analyzed using CiteSpace and VOSviewer software. Results: The total number of 2100 publications were included in the analysis. An overall increasing trend in the number of publications is observed between 2013 and 2023. Chinese publications were the most contributive, but United States publications were the most influential. Shanghai Jiao Tong University was the most active and prolific institution. Antioxidants was the most productive journal, while Oxidative Medicine and Cellular Longevity were the journals with the most-cited articles. Kaarniranta K, from Finland, was the most productive and influential author. Examination of co-cited references revealed that researchers in the field are primarily focused on investigating the molecular mechanisms, preventive strategies, and utilization of antioxidants to address retinal oxidative damage. Diabetic retinopathy, endothelial growth factor, retinitis pigmentosa, retinal degeneration, antioxidant response, retinal ganglion cells, and genes are the research hotspots in this field. Metabolism, sodium iodate, and system are at the forefront of research in this field. Conclusion: Attention toward retinal oxidative stress has increased over the past decade. Current research focuses on the mechanisms of retinal diseases related to oxidative stress and the experimental study of antioxidants in retinal diseases, which may continue to be a trend in the future.

3.
Int Immunopharmacol ; 135: 112281, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38762925

RESUMO

The administration of nonsteroidal anti-inflammatory drugs (NSAIDs) may cause significant intestinal alteration and inflammation and lead to the occurrence of inflammatory diseases resembling duodenal ulcers. Astragaloside IV (AS-IV) is a glycoside of cycloartane-type triterpene isolated from the dried root of Astragalus membranaceus (Fisch.) Bge. (family Fabaceae), and has been used for ameliorating the NSAID-induced inflammation in the small intestine. The present study aimed to investigate the effects of AS-IV on indomethacin (IND)-induced inflammation in the small intestine of rats and its underlying mechanisms. Hematoxylin-eosin (H&E) staining, transmission and scanning electron microscopy were carried out to observe the surface morphology and ultrastructure of the small intestinal mucosa. Immunofluorescence and ELISA tests were employed to detect the expressions of NLRP3, ASC, caspase-1, and NF-κB proteins, as well as inflammatory factors IL-1ß and IL-18, to uncover potential molecular mechanisms responsible for mitigating small intestinal inflammation. The results demonstrated that AS-IV significantly decreased the ulcer index, improved the surface morphology and microstructure of the small intestinal mucosa, and increased mucosal blood flow. Molecular docking revealed a strong and stable binding capacity of AS-IV to NLRP3, ASC, caspase-1, and NF-κB proteins. Further experimental validation exhibited that AS-IV markedly decreased levels of IL-1ß and IL-18, and inhibited the protein expression of NLRP3, ASC, caspase-1, and NF-κB. Our data demonstrate that AS-IV ameliorates IND-induced intestinal inflammation in rats by inhibiting the activation of NLRP3 inflammasome and reducing the release of IL-1ß and IL-18, thereby representing a promising therapy for IND-induced intestinal inflammation.


Assuntos
Indometacina , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos Sprague-Dawley , Saponinas , Triterpenos , Animais , Saponinas/farmacologia , Saponinas/uso terapêutico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Masculino , Ratos , Anti-Inflamatórios não Esteroides/farmacologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Intestino Delgado/metabolismo , Intestino Delgado/imunologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , NF-kappa B/metabolismo , Interleucina-1beta/metabolismo , Simulação de Acoplamento Molecular , Caspase 1/metabolismo , Inflamação/tratamento farmacológico , Inflamação/induzido quimicamente
4.
Medicine (Baltimore) ; 102(48): e36445, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38050286

RESUMO

Helicobacter pylori (H pylori) infection is a crucial element in chronic gastritis progression towards precancerous lesions of gastric cancer (PLGC) formation and, potentially, gastric cancer; however, screening for and eliminating H pylori has several challenges. This study aimed to assess the present research status, prominent themes, and frontiers of H pylori-related PLGC and to provide impartial evaluations of the developmental trends in this domain. This study extracted articles and review papers concerning H pylori-related PLGC published from 2013 to 2023 from the Web of Science Core Collection. The data was analyzed and visualized using VOSviewer and CiteSpace. The study encompassed 1426 papers, with a discernible upward trend in publications between 2013 and 2023. China emerged as the most productive country, whereas the United States exerted the greatest influence. Baylor College of Medicine was the most prolific institution. World Journal of Gastroenterology featured the highest number of published papers, whereas Gastroenterology was the most frequently cited journal. Kim N. from South Korea was the most prolific author. Co-cited literature pertained to various aspects such as gastritis classification, H pylori infection management, gastric cancer prevention, and managing patients with PLGC. Future research will focus on the Kyoto classification, cancer incidence, and gastric intestinal metaplasia. The results of this study indicate a persistent increase in attention directed toward H pylori-associated PLGC. The research emphasis has transitioned from molecular mechanisms, epidemiology, monitoring, and diagnosis to clinical prevention and treatment methodologies. The forthcoming research direction in this area will concentrate on controlling and preventing malignant PLGC transformation.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Gastrite/tratamento farmacológico , Lesões Pré-Cancerosas/diagnóstico , Bibliometria , Infecções por Helicobacter/tratamento farmacológico
5.
Integr Zool ; 18(4): 630-646, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36064198

RESUMO

Hainan gibbons are among the world's most critically endangered primates, with a remaining population of only 35 individuals distributed across 5 social groups in the Bawangling Branch of the Hainan Tropical Rainforest National Park, China. Habitat conversion and forest fragmentation over the past 40 years have reduced their geographical distribution by 95%. In the absence of a quantitative assessment of the availability of remaining suitable habitat, it is unclear whether this species can survive to the end of this century. We used behavioral observations, ArcGIS, remote sensing, stereo optical imagery, and MaxEnt modeling to identify patterns of Hainan gibbon range use and compare changes in the distribution of suitable forest types and areas of forest fragmentation over the past 20 years (2000-2020). The results indicate that the combined range of the 5 extant Hainan gibbon groups totaled 14.89 km2 . The home range of the smallest group (Group E, 3 individuals) was 1.51 km2 , which likely represents the minimum home range size for this species. The remaining area of highly suitable and moderately suitable habitat totals 26.9 km2 . However, habitat connectivity across the gibbon range is very low (less than 0.5), limiting the ability of Hainan gibbons to move between forest patches. The results of this study indicate that the availability of suitable habitat in Bawangling is insufficient to allow for future Hainan gibbon population growth. Therefore, immediate action must be taken to restore, reforest, and establish ecological corridors to reconnect areas of suitable habitat for these critically endangered gibbons.


Assuntos
Hylobates , Hylobatidae , Animais , Espécies em Perigo de Extinção , Ecossistema , China
6.
Biomed Pharmacother ; 156: 113866, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36228371

RESUMO

Huang-Qi-Jian-Zhong-Tang (HQJZT) is a well-known traditional Chinese herbal formulation. This study aimed to investigate the duodenoprotective properties of HQJZT against Indomethacin (IND)-induced duodenal ulceration in rats, and the mechanisms involved, particularly through NF-κB and STAT signaling pathways. Our results showed that HQJZT completely protected the duodenal mucosa from ulceration caused by IND, as indicated by improved macroscopic and histological appearances. There was a significant decrease in ulcer index and microscopic score, an increase in villus height and crypt depth, and a normalization of the tissue architecture of the duodenum in rats following HQJZT treatment. Blood flow into the duodenal mucosa was significantly increased after HQJZT administration. HQJZT significantly increased PGE2 and NO levels in the duodenal mucosa. A significant reduction in the production of pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α was observed in the duodenal mucosa under treatment with HQJZT. Mechanistically, the administration of HQJZT significantly lowered the duodenal protein expression of inflammation-related genes, including p-NF-κB and p-IκBß, compared with the ulcer control group. Furthermore, the STAT signaling pathway-related protein markers p-JAK and p-STAT were significantly reduced in the HQJZT (1.30 and 2.60 g/kg) groups. As a result of these findings, HQJZT alleviates duodenal mucosal ulcers caused by IND. A protective effect of HQJZT on duodenal ulcers is attributed to its ability to improve mucosal blood flow, stimulate the production of cytoprotective mediators, minimize proinflammatory cytokines, and block the activation of NF-κB and STAT signaling pathways.


Assuntos
Medicamentos de Ervas Chinesas , Úlcera Duodenal , Animais , Ratos , Citocinas/metabolismo , Úlcera Duodenal/induzido quimicamente , Úlcera Duodenal/tratamento farmacológico , Indometacina/toxicidade , Medicina Tradicional Chinesa , NF-kappa B/metabolismo , Transdução de Sinais , Medicamentos de Ervas Chinesas/uso terapêutico
7.
Curr Zool ; 68(3): 265-273, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35592348

RESUMO

Sex-biased dispersal is common in group-living animals. Due to differences in local demographic and environmental factors, sex-biased dispersal presents many irregular patterns. In this study, a habituated, individually identified Yunnan snub-nosed monkey Rhinopithecus bieti group was observed over 9 years; 192 dispersal events, including 97 male dispersal events (25 natal dispersal and 72 secondary dispersal) and 95 female dispersal events (34 natal dispersal and 61 secondary dispersal) were observed. Males and females showed different dispersal paths, dispersal ages, and dispersal patterns. Females had 2 dispersal paths, whereas males had 4 paths. In terms of age of dispersal, the male age of natal dispersal was younger than for females. Males prefer single dispersal, whereas females prefer parallel dispersal. Our study indicates that the dispersal pattern of R. bieti should be classified as a bisexual dispersal pattern. The differences in dispersal path, average age at dispersal, and dispersal path pattern indicate that Yunnan snub-nosed monkeys may still retain a loose matrilineal social system.

8.
Animals (Basel) ; 11(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34679936

RESUMO

We used long-term data on the variation in harem size in Yunnan snub-nosed monkeys to research the effects of harem size on reproductive success and the ratio of grooming received to given (RGRG). The results suggest that harem holders derive reproductive benefits commensurate with harem size, whereas the females' reproductive success is unaffected by harem size. Males of larger harems groomed less and had higher RGRG than males of smaller harems. In the case of females, grooming given increased, and RGRG decreased with an increase in harem size. The males' reproductive success seems to be a driver of harem size maximization. From the females' perspective, dwindling social benefits appear to set the upper limit for harem enlargement. We also showed that males of monogamous units ('single-female harems') invested more into grooming their female, presumably to prevent unit disintegration and loss of mating privileges.

9.
J Environ Manage ; 297: 113331, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34298347

RESUMO

In many areas of South Asia and Southeast Asia, macaques inhabiting agricultural landscapes are considered serious crop pests by local farmers. In Nepal, for example, the expansion of monocultures, increased forest fragmentation, the degradation of natural habitats, and changing agricultural practices have led to a significant increase in the frequency of human-macaque conflict. In order to more fully understand the set of factors that contribute to macaque crop raiding, and the set of preventive measures that can be put in place to avoid human-macaque conflict, we examined patterns of crop raiding by a group of 52 rhesus macaques (Macaca mulatta) in the Kavrepalanchok district, Nepal. We present data on macaque inflicted crop damage in 172 agricultural plots (each plot measuring 380 m2) from August to October 2019. Our results indicate that farmland invasions by macaques were principally affected by crop type (maize was preferred over rice), nearness of farmland to both the forest edge and the major travel route used by the macaques, and the mitigation efforts applied by farmers to discourage crop raiding. We found that as the proportion of maize farmland in the most direct path from the macaque's main travel route to nearby crop raiding sites increased, the amount of maize damage decreased. This is likely explained by the fact that macaques traveling across several adjacent maize fields encounter multiple farmers protecting their crops. We estimated that the financial cost to individual farmer households of macaque maize and rice raiding was on average US$ 14.9 or 4.2% of their annual income from cultivating those two crops. As human-macaque conflict is one of the most critical challenges faced by wildlife managers in South Asia and Southeast Asia, studies of macaque crop raiding behavior provide an important starting point for developing effective strategies to manage human-macaque conflict while promoting both primate conservation and the economic well-being of the local community.


Assuntos
Agricultura , Animais Selvagens , Animais , Produtos Agrícolas , Macaca mulatta , Nepal
10.
Folia Primatol (Basel) ; 91(3): 202-218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31722344

RESUMO

Animal life activities are rhythmic and affected by seasonal periodicity. Based on 9 years of observations, we estimated the reproductive parameters of a wild, but provisioned Yunnan snub-nosed monkey (Rhinopithecus bieti) group at Xiangguqing in Baimaxueshan National Nature Reserve, Yunnan Province, China. We observed 84 infants (43 males and 41 females) from 41 females between 2010 and 2018. We found the birth sex ratio was 1:1, the female age at first birth was 6.13 years and infant mortality was about 15.5%. Nine years of data showed that the maximum birth season lasted 126 days, and the average length per year was 98.57 ± 18.71 days. R. bieti,characterized by strictly seasonal reproduction, started giving birth on February 1, and this ended on June 7, with a peak reached from March 4 to March 11 (10th week). The mean birth date was March 20 (79.21 ± 29.54 days), and the median birth date was March 11 (71st day). The mean interbirth interval (IBI) was approximately 2 years, and the IBIs among females whose infants had survived for 1 year were found to be significantly longer than those found in females who lost their infant within 1 year. Comparing the reproduction parameters among Asian and African colobines, we concluded that Asian and African colobines tend to have an IBI of 2 years or more, females tend to give birth at the age of 5-6 years, Rhinopithecus species had a strict seasonal reproductive pattern concentrated in February to April. Seasonal changes in food resources and climatic factors may be the main reasons for the variation in reproductive parameters in intraspecific and interspecific comparisons of Asian and African colobines.


Assuntos
Colobinae/fisiologia , Reprodução/fisiologia , Animais , Animais Recém-Nascidos , Intervalo entre Nascimentos , China , Feminino , Humanos , Masculino , Gravidez , Estações do Ano , Razão de Masculinidade , Comportamento Sexual Animal
11.
Zool Res ; 41(1): 78-83, 2020 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-31746565

RESUMO

Individual dispersal trends, unquestionably important for species ecology and evolution, are affected by multiple factors. Understanding the factors that influence female dispersal strategies offers important insight into primate dispersal mechanisms and female choice. To investigate the proximate causes of dispersal in female Yunnan snub-nosed monkeys (Rhinopithecus bieti), we observed and analyzed nine years of detailed dispersal and demographic data from a population of R. bieti in Xiangguqing, Baimaxueshan Nature Reserve, Yunnan Province, China. Results showed that females who lived long-term in a one-male unit (OMU), without giving birth and with few or no relatives, were more likely to leave that OMU. In addition, an OMU led by an outgroup male and containing more female relatives was significantly more likely to be chosen for immigration. Conversely, greater male age, longer male tenure, and more potentially fertile females discouraged immigration into an OMU. These results suggest that reproduction, male quality, and kin cooperation play the largest roles in female Yunnan snub-nosed monkey dispersal.


Assuntos
Distribuição Animal , Comportamento Animal , Presbytini/fisiologia , Comportamento Social , Envelhecimento , Animais , Feminino , Masculino
12.
PeerJ ; 7: e6633, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886785

RESUMO

In this study, we integrate data from field investigations, spatial analysis, genetic analysis, and Generalized Linear Models (GLMs) to evaluate the effects of habitat fragmentation on the population dynamics, genetic diversity, and range shifts in the endangered Yunnan snub-nosed monkey (Rhinopithecus bieti). The results indicate that from 1994 to 2016, R. bieti population size increased from less than 2,000 to approximately 3,000 individuals. A primary factor promoting population recovery was the establishment of protected nature reserves. We also found that subpopulation growth rates were uneven, with the groups in some areas, and the formation of new groups. Both the fragmentation index, defined as the ratio of the number of forest patches to the total area of forest patches (e.g., increased fragmentation), and increasing human population size had a negative effect on population growth in R. bieti. We recommend that government conservation plans prioritize the protection of particular R. bieti populations, such as the Baimei and Jisichang populations, which have uncommon haplotypes. In addition, effective conservation strategies need to include an expansion of migration corridors to enable individuals from larger populations such as Guyoulong (Guilong) to serve as a source population to increase the genetic diversity of smaller R. bieti subpopulations. We argue that policies designed to protect endangered primates should not focus solely on total population size but also need to determine the amount of genetic diversity present across different subpopulations and use this information as a measure of the effectiveness of current conservation policies and the basis for new conservation policies.

13.
Am J Primatol ; 80(11): e22914, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30307631

RESUMO

Male-male interactions in mixed-sex groups of social mammals are typically characterized by a mix of hostility and affiliation, as a result of inherent conflicts over mating opportunities, and the costs and benefits of social alliances, co-operative behaviors, and coalitionary defense. In species of nonhuman primates that form all-male groups, it is still unclear how the tradeoffs between the benefits of forming an all-male group and the cost of male-male competition in seeking mating opportunities with females in bisexual groups influence social cohesion in different seasons. Here, we used social network analysis to quantify the impact of reproductive seasonality on social cohesion and clique size of bachelor males residing in an all-male unit (AMU) in wild black-and-white snub-nosed monkeys (Rhinopithecus bieti). These primates are strict seasonal breeders and live in a modular social system composed of a number of one-male units (OMUs) and an associated peripheral AMU. We found that the AMU social network had a significantly lower density, centralization, clustering coefficient, and smaller clique size during the mating season compared to the non-mating period. However, aggression among AMU males during both mating and non-mating periods was low. Our results suggest that network structure topology in male same-sex social units is modulated by seasonal changes. Bachelor males engage in two types of competition to gain reproductive success: first, which is analogous to contest competition, in which bachelor males act aggressively and challenge OMU leader males in an attempt to take over an OMU; and second, which is more analogous to scramble competition, in which bachelor males avoid aggressive interactions and instead engage in sneaky copulations with fertile females. Our work adds to an understanding of the maintenance of all-male groups in species that form a multilevel society.


Assuntos
Agressão , Colobinae/fisiologia , Estações do Ano , Comportamento Social , Animais , Comportamento Competitivo , Copulação , Feminino , Masculino , Reprodução/fisiologia
14.
Gigascience ; 7(9)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30165519

RESUMO

Background: The rhesus macaque (RM, Macaca mulatta) is the most important nonhuman primate model in biomedical research. We present the first genomic survey of wild RMs, sequencing 81 geo-referenced individuals of five subspecies from 17 locations in China, a large fraction of the species' natural distribution. Results: Populations were structured into five genetic lineages on the mainland and Hainan Island, recapitulating current subspecies designations. These subspecies are estimated to have diverged 125.8 to 51.3 thousand years ago, but feature recent gene flow. Consistent with the expectation of a larger body size in colder climates and smaller body size in warmer climates (Bergman's rule), the northernmost RM lineage (M. m. tcheliensis), possessing the largest body size of all Chinese RMs, and the southernmost lineage (M. m. brevicaudus), with the smallest body size of all Chinese RMs, feature positively selected genes responsible for skeletal development. Further, two candidate selected genes (Fbp1, Fbp2) found in M. m. tcheliensis are involved in gluconeogenesis, potentially maintaining stable blood glucose levels during starvation when food resources are scarce in winter. The tropical subspecies M. m. brevicaudus showed positively selected genes related to cardiovascular function and response to temperature stimuli, potentially involved in tropical adaptation. We found 118 single-nucleotide polymorphisms matching human disease-causing variants with 82 being subspecies specific. Conclusions: These data provide a resource for selection of RMs in biomedical experiments. The demographic history of Chinese RMs and their history of local adaption offer new insights into their evolution and provide valuable baseline information for biomedical investigation.


Assuntos
Aclimatação/genética , Genética Populacional , Macaca mulatta/genética , Animais , Pesquisa Biomédica , China , Humanos
15.
Folia Primatol (Basel) ; 88(4): 358-383, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29041006

RESUMO

The social organization of natural groups of Rhinopithecus bieti (Yunnan snub-nosed monkey) is virtually unknown. We studied the demography and social structure of a free-ranging group at Samage Forest, China, for nearly 2 years. This study confirmed that R. bieti exhibits a multilevel social organization of core 1-male units (OMUs) that congregate in a band of >400 members. Even though the band appeared to be unified for the most part, we also witnessed occasional fission-fusion. OMUs were cohesive entities, and their members were spatially and socially isolated from members of other OMUs. Large all-male units associated with the band, and when they closely followed OMUs there was a tendency for elevated male aggression. Within OMUs, females associated preferentially with males and vice versa, resulting in a bisexually bonded society. Contrary to other Asian colobines, R. bieti were comparatively social, with grooming occupying 7.3% of the time. Social grooming was primarily a female affair, but males also participated in grooming networks. The integration of males into the social network of the OMU is thought to help to maintain OMU integrity and cohesion with other social units being in close proximity.


Assuntos
Colobinae/fisiologia , Comportamento Social , Animais , China
16.
Mol Biol Evol ; 33(10): 2670-81, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27555581

RESUMO

Snub-nosed monkeys (genus Rhinopithecus) are a group of endangered colobines endemic to South Asia. Here, we re-sequenced the whole genomes of 38 snub-nosed monkeys representing four species within this genus. By conducting population genomic analyses, we observed a similar load of deleterious variation in snub-nosed monkeys living in both smaller and larger populations and found that genomic diversity was lower than that reported in other primates. Reconstruction of Rhinopithecus evolutionary history suggested that episodes of climatic variation over the past 2 million years, associated with glacial advances and retreats and population isolation, have shaped snub-nosed monkey demography and evolution. We further identified several hypoxia-related genes under selection in R. bieti (black snub-nosed monkey), a species that exploits habitats higher than any other nonhuman primate. These results provide the first detailed and comprehensive genomic insights into genetic diversity, demography, genetic burden, and adaptation in this radiation of endangered primates.


Assuntos
Adaptação Fisiológica/genética , Colobinae/genética , Hipóxia/veterinária , Aclimatação/genética , Adaptação Biológica/genética , Animais , Sequência de Bases , Ecossistema , Variação Genética , Hipóxia/genética , Hipóxia/metabolismo , Metagenômica/métodos , Filogenia , Polimorfismo Genético , Análise de Sequência de DNA/veterinária
17.
Am J Primatol ; 78(9): 974-82, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27273623

RESUMO

In many primate species that form one-male breeding units (OMUs), the threat of a takeover by a bachelor male represents a major challenge to group stability and individual reproductive success. In the case of snub-nosed monkeys, which live in large multilevel or modular societies (MLS) comprising several OMUs that travel, feed and rest together and as well as one or more all male units (AMUs), the process by which rival males challenge resident OMU males for access to females is poorly understood. From September 2012 to October 2013, we recorded 48 cases in which rival males visited an OMU in a MLS of Yunnan snub-nosed monkeys (Rhinopithecus bieti) inhabiting the Baimaxueshan National Nature Reserve, Yunnan Province, China. In 40 cases, rival males engaged in mild agonistic interactions (approaching, staring, teeth-baring and chasing) but failed to take over the group; we counted these visits as failed takeovers, recognizing that they may nevertheless allow rival males to assess the competitive ability of residents. During eight successful takeovers, however, there was severe physical aggression between challenging and resident males, with serious injuries to participants. We found that neither the number of adult and subadult females in an OMU, the number of non-pregnant, non-lactating adult females in an OMU, nor the rank of a resident male relative to other resident males in the MLS predicted which OMU a challenging male targeted for takeover. However, a resident male's rank significantly predicted whether takeover attempts were successful. Specifically, challenging males were more successful in displacing a lower-ranking resident male than a higher-ranking male. Given that a Yunnan snub-nosed monkey MLS may contain as many as 40 resident and 36 bachelor males, continued research is required to determine the set of factors that enable resident males to maintain high social rank and successfully defend their harems. Am. J. Primatol. 78:974-982, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Agressão , Colobinae , Comportamento Social , Animais , Feminino , Masculino , Gravidez , Reprodução
18.
Folia Primatol (Basel) ; 87(6): 349-360, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28110326

RESUMO

The appearance of tourists brings about behavioural changes in some primates. Primate behavioural responses to human activities can reflect their survival strategy. Little is known about how the behaviour of Rhinopithecus bieti changes in the presence of tourists. Here we provide the first detailed description of interactions between a provisioned group of R. bieti and tourists at Xiangguqing in Baimaxueshan Nature Reserve from July 2012 to June 2013. We found that R. bieti had different response rates to the 5 most common human actions (shout, photograph, offer food, clap, and wave). Results indicated that R. bieti expresses 10 behavioural reactions (threat, escape, vigilance, warning, panic, alliance, attack, foraging, approach, and staring) to tourists' actions. On the whole, most of the monkeys' responses were unfriendly or hostile; a small number were neutral and affiliative. Behavioural responses were also significantly different among the different age/sex classes. Immature individuals engaged in more affiliative behaviours than adult individuals, and adult males tended towards more hostile behaviours. The behaviour of R. bieti towards tourists showed both tension and adaptability. Scientific management of provisioned monkey groups and strict regulation of tourist behaviour is needed in order to protect the animals from the negative effects of tourism-related disturbance.


Assuntos
Comportamento Animal , Colobinae/fisiologia , Fatores Etários , Agressão , Animais , China , Feminino , Habituação Psicofisiológica , Humanos , Masculino , Fatores Sexuais
19.
Conserv Biol ; 29(6): 1508-17, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26372167

RESUMO

Most of China's 24-28 primate species are threatened with extinction. Habitat reduction and fragmentation are perhaps the greatest threats. We used published data from a conservation genetics study of 5 endangered primates in China (Rhinopithecus roxellana, R. bieti, R. brelichi, Trachypithecus francoisi, and T. leucocephalus); distribution data on these species; and the distribution, area, and location of protected areas to inform conservation strategies for these primates. All 5 species were separated into subpopulations with unique genetic components. Gene flow appeared to be strongly impeded by agricultural land, meadows used for grazing, highways, and humans dwellings. Most species declined severely or diverged concurrently as human population and crop land cover increased. Nature reserves were not evenly distributed across subpopulations with unique genetic backgrounds. Certain small subpopulations were severely fragmented and had higher extinction risk than others. Primate mobility is limited and their genetic structure is strong and susceptible to substantial loss of diversity due to local extinction. Thus, to maximize preservation of genetic diversity in all these primate species, our results suggest protection is required for all sub-populations. Key priorities for their conservation include maintaining R. roxellana in Shennongjia national reserve, subpopulations S4 and S5 of R. bieti and of R. brelichi in Fanjingshan national reserve, subpopulation CGX of T. francoisi in central Guangxi Province, and all 3 T. leucocephalus sub-populations in central Guangxi Province.


Assuntos
Distribuição Animal , Colobinae/fisiologia , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Variação Genética , Animais , China , Colobinae/genética , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Fluxo Gênico , Haplótipos , Filogenia , Análise de Sequência de DNA/veterinária
20.
R Soc Open Sci ; 2(12): 150490, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27019735

RESUMO

Sexual selection typically produces ornaments in response to mate choice, and armaments in response to male-male competition. Unusually among mammals, many primates exhibit colour signals that may be related to one or both processes. Here, we document for the first time correlates of facial coloration in one of the more brightly coloured primates, the black-and-white snub-nosed monkey (Rhinopithecus bieti). Snub-nosed monkeys have a one-male unit (OMU) based social organization, but these units aggregate semi-permanently into larger bands. This form of mating system causes many males to become associated with bachelor groups. We quantified redness of the prominent lower lip in 15 males (eight bachelors, seven OMU holders) in a group at Xiangguqing, China. Using mixed models, our results show that lip redness increases with age. More interestingly, there is a significant effect of the interaction of group-holding status and mating season on redness; that is, lip colour of OMU males undergoes reddening in the mating season, whereas the lips of subadult and juvenile bachelor males become paler at that time of year. These results indicate that lip coloration is a badge of (group-holding) status during the mating season, with non-adults undergoing facial differentiation, perhaps to avoid the costs of reproductive competition. Future research should investigate whether lip coloration is a product of male-male competition, and/or female mate choice.

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