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1.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1975-1980, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694482

RESUMO

To reveal the effects of nitrogen (N) inputs and mowing on the abundance and richness of insect community in meadow steppe, we investigated the abundance and diversity of herbivorous insects under four treatments in Inner Mongolia meadow steppe in August 2022, including control, N addition, mowing, and combined N addition and mowing. At a long-term control experimental platform, we collected insects using the vacuum sampling method. The results showed that N addition significantly increased the abundance of herbivorous insects, and mowing significantly decreased the abundance of herbivorous insects. Nitrogen addition significantly increased insect abundance in unmown condition but not in the mown condition. The responses of insect abundance at the community level to N addition were mainly driven by the dominant groups, Cicadellidae and Lygaeidae, which was affected by the abundance of Gramineae species. In contrast, their responses to mowing were the opposite. Both N addition and mowing did not affect the diversity of herbivorous insects. Our results indicated that the responses of herbivorous insect abundance to N inputs and mowing were directly regulated by food resources. With increasing food resource availability, the abundance but not the diversity of herbivorous insects increased, with stronger responses of dominant groups than subordinate ones.


Assuntos
Pradaria , Insetos , Animais , China , Herbivoria , Nitrogênio
2.
Behav Processes ; 200: 104671, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35661792

RESUMO

A major challenge in behavior and evolutionary ecology is to understand the evolution and maintenance of animal personality. Theory suggests that females can benefit by choosing a high-quality mate, but largely ignores the potential interaction between male and female personality during mate choice. Here, we examined the influence of exploration on mate choice by captive female Java sparrows (Lonchura oryzivora). Females preferred high exploratory males as mates rather than choosing mates according to their own exploration, and thus showed no assortative mating. Our results highlight the role of exploration of males in the mate preference of birds and suggest that mate compatibility plays minor role in the mate preference.


Assuntos
Preferência de Acasalamento Animal , Pardais , Animais , Feminino , Masculino , Reprodução
3.
BMC Gastroenterol ; 20(1): 202, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590950

RESUMO

BACKGROUND: Undifferentiated carcinoma with osteoclast-like giant cells (UC-OGC) is an extremely uncommon pancreatic neoplasm that comprises less than 1% of all exocrine pancreatic tumors. To date, cases and data from whole-exome sequencing (WES) analysis have been reported by specific studies. We report a case of pancreatic UC-OGC with a literature review, and provide novel insights into the molecular characteristics of this tumor entity. CASE PRESENTATION: A 31-year-old male presented with intermittent abdominal pain for several months, and positron emission tomography (PET) showed isolated high metabolic nodules during the pancreatic uncinate process that were likely to be malignant disease. Pathological examination after radical excision revealed UC-OGC associated with poorly differentiated adenocarcinoma at the head of the pancreas. The disease recurred 7.4 months after radical surgery. The KRAS p.G12D (c.35G > A) and somatic BRCA2 p.R2896C (c.8686C > T) mutations were detected by subsequent WES analysis. The patient showed no response to platinum-based systemic chemotherapy, and his condition quickly worsened. He finally died, with an overall survival of 1 year. CONCLUSIONS: As an extremely uncommon tumor entity, UC-OGC is really a unique variant of conventional pancreatic ductal adenocarcinoma due to its similarities, as shown by genomic WES analysis. Clinical examination and molecular analysis by WES could further indicate potential treatment strategies for UC-OGC.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , Adulto , Células Gigantes , Humanos , Masculino , Mutação , Recidiva Local de Neoplasia , Osteoclastos , Pâncreas , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Sequenciamento do Exoma
4.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3903-3910, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833704

RESUMO

Nematodes, occupying multiple trophic levels in the food web, play important roles in energy flow and nutrient cycling. Most of Chinese natural grasslands have been degraded due to long-term unreasonable utilization, such as over-grazing. External nutrient input is an important way to restore the ecological function of degraded grasslands. The main and intertative effects of nitrogen and phosphorus inputs on soil nematode abundance, trophic group composition and community structure were studied in the grasslands in Xilingol League of Inner Mongolia. Totally, 38 genera of nematodes were recorded. Tylencholaimus, Aphelenchoides, Thonus, and Scutylenchus were dominant genera in this degraded grassland. Nitrogen input decreased total abundances of soil nematodes, and that of omnivores-carnivorous nematodes and plant-feeding nematodes. Phosphorus input increased total abundances of soil nematodes, and that of fungal-feeding nematodes, omnivores-carnivorous nematodes, and plant-feeding nematodes. Nitrogen input inhibited the positive effects of phosphorus input on the abundances of total nematodes, omnivores-carnivorous nematodes and plant-feeding nematodes. Nutrient inputs had no effect on nematode diversity, which would be resulted from the stable plant community. Nitrogen input significantly increased nematode maturity index, decreased plant parasitic nematode maturity index (PPI), and greatly alleviated the negative effects of phosphorus input on PPI and Wasilewska index, indicating that nitrogen input could improve soil health condition and the stability of nematodes community. Our results would help improve our understanding of the effects of nutrient inputs on degraded grassland ecosystem from a soil biotic perspective.


Assuntos
Nematoides , Solo , Animais , China , Ecossistema , Pradaria , Nitrogênio , Fósforo
5.
Sci Total Environ ; 666: 887-893, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-30818212

RESUMO

AIMS: The stoichiometric characteristics of plant communities are important controller for several fundamental ecological processes. The effects of environmental changes on community stoichiometric characteristics are driven by intra- and inter-specific variation. However, the relative importance of both pathways has seldom been empirically examined. METHODS: We quantified the relative contribution of intra- and inter-specific variation to the changes of community nitrogen (N) and phosphorus (P) concentrations after seven-year factorial N addition and mowing treatments in a semi-arid grassland of northern China. RESULTS: Nitrogen addition significantly increased community N and P concentrations and N:P ratio. Mowing significantly increased community N concentration and N:P. Intra-specific variation contributed more than inter-specific variation to the total variability of all the nutritional and stoichiometric characteristics, with intra-specific variation accounting for 68%, 70%, and 75% of the total variation in community-level N, P, and N:P, respectively. Negative covariations between the contribution of intra- and inter-specific variation occurred for community N and P concentrations. Further, N addition and mowing interacted to affect the impacts of intra- and inter-specific variation on community N concentration and N:P stoichiometry. CONCLUSIONS: Our results highlight different ways of trait selection for N addition and mowing treatments. Interactions between those two factors make it more difficult to accurately predict the responses of plant-mediated biogeochemical cycles under co-occurrence of environmental changes.


Assuntos
Fertilizantes/análise , Pradaria , Nitrogênio/metabolismo , Plantas/metabolismo , China , Especificidade da Espécie
6.
J Environ Pathol Toxicol Oncol ; 36(4): 309-320, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29431063

RESUMO

Purpose - We aimed to assess whether Helicobacter pylori infection influences prognosis in gastric cancer patients (GC). Methods - We systematically searched MEDLINE, PubMed, EBSCO, EMBASE, and the Cochrane Library (CENTRAL) Register from inception to June 1, 2017. Overall survival (mean OS) or disease-free survival (mean DFS) in GC patients were calculated using the hazard ratio (HR) and 95% confidence intervals (95% CIs). Results - In total, 19 articles with 4,321 GC patients were enrolled. Helicobacter pylori infection is associated with longer OS (HR 0.73; 95% CI 0.60-0.89; P < 0.001) and DFS (HR 0.75; 95% CI 0.53-1.07; P = 0.002) in GC patients overall. For our subgroup analysis, the pooled HRs and 95% CIs were as follows: China (OS: HR 0.95; 95% CI 0.63-1.42; P = 0.804 and DFS: HR 0.88; 95% CI 0.50-1.56; P = 0.658), Europe (OS: HR 0.69; 95% CI 0.52-0.92; P = 0.010 and DFS: HR 0.62; 95% CI 0.32-1.17; P = 0.141), United States (OS: HR 0.77: 95% CI 0.56-1.06; P = 0.105), Korea (OS: HR 0.45; 95% CI 0.27-0.75; P = 0.002 and DFS: HR 0.45; 95% CI 0.24-0.83, P = 0.011), and Turkey (OS: HR 0.94; 95% CI 0.52-1.70; P = 0.839 and DFS: HR 0.95; 95% CI 0.53-1.71, P = 0.864). Moreover, for R0 or M0 patients, H. pylori infection is associated with better OS and DFS (P all values < 0.05). Conclusions - Helicobacter pylori infection has a better prognosis in GC patients from Korea and Europe. Helicobacter pylori infection has no association with prognosis for China, the United States, or Turkey. Also, H. pylori infection has a better prognosis in R0 resection or M0 GC patients.


Assuntos
Infecções por Helicobacter/mortalidade , Helicobacter pylori , Neoplasias Gástricas/mortalidade , Humanos , Metástase Neoplásica , Prognóstico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
7.
Acta Biol Hung ; 64(4): 426-37, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24275589

RESUMO

FoxP2 is a member of the winged helix/forkhead class of transcription factors. Despite FoxP2 is found to have particular relevance to speech and language, the role of this gene is broader and not yet fully elucidated. In this study, we investigated the expression of FoxP2 in the brains of bats with different feeding habits (two frugivorous species and three insectivorous species). We found FoxP2 expression in the olfactory tubercle of frugivorous species is significantly higher than that in insectivorous species. Difference of FoxP2 expression was not observed within each of the frugivorous or insectivorous group. The diverse expression patterns in olfactory tubercle between two kinds of bats indicate FoxP2 has a close relation with olfactory tubercle associated functions, suggesting its important role in sensory integration within the olfactory tubercle and such a discrepancy of FoxP2 expression in olfactory tubercle may take responsibility for the different feeding behaviors of frugivorous and insectivorous bats.


Assuntos
Quirópteros/metabolismo , Comportamento Alimentar/fisiologia , Fatores de Transcrição Forkhead/metabolismo , Condutos Olfatórios/metabolismo , Olfato/fisiologia , Animais , Feminino , Masculino
8.
Rev Biol Trop ; 59(1): 455-63, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21513205

RESUMO

Tropical forests vegetation and community research have tended to focus on the tree component, and limited attention has been paid to understory vegetation. Species diversity and composition of the understory of tropical seasonal rain forest were inventoried in a 625 m2 area (for sapling layer) and a 100 m2 area (for herb/seedling layer) in three 1 ha plots. We found 3068 individuals belonging to 309 species, 192 genera and 89 families. The most important family as determined by the Family Importance Value (FIV) was Rubiaceae in both sapling and herb/seedling layers. In terms of Importance Value Index (IVI), the shrub Mycetia gracilis (Rubiaceae) was the most important species in the sapling layer and the pteridophyte Selaginella delicatula (Selaginellaceae) was the most ecological significant species in the herb/seedling layer. Much more vascular plant species were registered in the understory than in the tree layer totaled among the three plots. The species diversity did not differ significantly among the tree layer, sapling layer and herb/seedling layer. Given that we still know little about the understory plant community for growth forms other than trees, the results from the present study indicate that more attention should be paid to the understory vegetation during the decision-making process for biodiversity conservation in the tropical forests.


Assuntos
Biodiversidade , Biomassa , Magnoliopsida/classificação , Árvores , China , Estações do Ano , Clima Tropical
9.
Sci China C Life Sci ; 52(9): 802-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19802737

RESUMO

The distribution and ultrastructure of Merkel cells were described in detail in piscivorous bats through immunohistochemistry and transmission electron microscopy techniques. The findings indicated that Merkel cells are commonly found in raised-domes, hair follicles and in the basal epidermis of the skin from their back, abdomen, intercrural membranes, wing membranes and footpads. However, the density of Merkel cells is significantly higher in the footpad than in other places. These results suggested that there may be a link between Merkel cells and tactile sense, and also might imply that raised-domes with air-flow sensitive hairs played an important role in adjusting flying gestures by monitoring the air flow around the body. The ultrastructure of Merkel cells is similar to other vertebrates except having more intermediate filaments and larger granules.


Assuntos
Quirópteros/anatomia & histologia , Células de Merkel/ultraestrutura , Animais , Quirópteros/metabolismo , Imuno-Histoquímica , Queratina-20/metabolismo , Células de Merkel/metabolismo , Microscopia Eletrônica de Transmissão , Pele/citologia , Pele/metabolismo
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