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The global challenge of male infertility is escalating, notably due to the decreased testosterone (T) synthesis in testicular Leydig cells under stress, underscoring the critical need for a more profound understanding of its regulatory mechanisms. CREBZF, a novel basic region-leucine zipper transcription factor, regulates testosterone synthesis in mouse Leydig cells in vitro; however, further validation through in vivo experiments is essential. Our study utilized Cyp17a1-Cre to knock out CREBZF in androgen-synthesis cells and explored the physiological roles of CREBZF in fertility, steroid hormone synthesis, and behaviors in adult male mice. Conditional knockout (cKO) CREBZF did not affect fertility and serum testosterone level in male mice. Primary Leydig cells isolated from CREBZF-cKO mice showed impaired testosterone secretion and decreased mRNA levels of Star, Cyp17a1, and Hsd3b1. Loss of CREBZF resulted in thickening of the adrenal cortex, especially X-zone, with elevated serum corticosterone and dehydroepiandrosterone levels and decreased serum dehydroepiandrosterone sulfate levels. Immunohistochemical staining revealed increased expression of StAR, Cyp11a1, and 17ß-Hsd3 in the adrenal cortex of CREBZF-cKO mice, while the expression of AR was significantly reduced. Along with the histological changes and abnormal steroid levels in the adrenal gland, CREBZF-cKO mice showed higher anxiety-like behavior and impaired memory in the elevated plus maze and Barnes maze, respectively. In summary, CREBZF is dispensable for fertility, and CREBZF deficiency in Leydig cells promotes adrenal function in adult male mice. These results shed light on the requirement of CREBZF for fertility, adrenal steroid synthesis, and stress response in adult male mice, and contribute to understanding the crosstalk between testes and adrenal glands.
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Corteza Suprarrenal , Células Intersticiales del Testículo , Ratones Noqueados , Animales , Masculino , Ratones , Células Intersticiales del Testículo/metabolismo , Corteza Suprarrenal/metabolismo , Andrógenos/metabolismo , Testosterona/sangre , Testosterona/metabolismo , Conducta Animal , Ratones Endogámicos C57BLRESUMEN
The significance of ecological non-monotonicity (a function whose first derivative changes signs) in shaping the structure and functions of the ecosystem has recently been recognized, but such studies involving high-order interactions are rare. Here, we have proposed a three-trophic conceptual diagram on interactions among trees, rodents, and insects in mast and non-mast years and tested the hypothesis that oak (Quercus wutaishanica) masting could result in increased mutualism and less predation in an oak-weevil-rodent system in a warm temperate forest of China. Our 14-year dataset revealed that mast years coincided with a relatively low rodent abundance but a high weevil abundance. Masting not only benefited seedling recruitment of oaks through increased dispersal by rodents but also a decrease in predation by rodents and weevils, as well as an increase in the overwintering survival of rodents. Masting appeared to have increased weevil survival by reducing predation of infested acorns by rodents. These results suggest that masting benefits all participants in the plant-insect-rodent system by increasing mutualism and reducing predation behavior (i.e., a non-monotonic function). Our study highlights the significance of masting in maintaining the diversity and function of the forest ecosystem by facilitating the transformation from predation to mutualism among trophic species.
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Conducta Predatoria , Quercus , Roedores , Simbiosis , Gorgojos , Animales , Quercus/fisiología , Gorgojos/fisiología , Conducta Predatoria/fisiología , Roedores/fisiología , China , Ecosistema , Bosques , Cadena AlimentariaRESUMEN
The relentless drive toward miniaturization in microelectronic devices has sparked an urgent need for materials that offer both high thermal conductivity (TC) and excellent electrical insulation. Thermal interface materials (TIMs) possessing these dual attributes are highly sought after for modern electronics, but achieving such a combination has proven to be a formidable challenge. In this study, a cutting-edge solution is presented by developing boron nitride (BN) and graphite films layered silicone rubber composites with exceptional TC and electrical insulation properties. Through a carefully devised stacking-cutting method, the high orientation degree of both BN and graphite films is successfully preserved, resulting in an unprecedented through-plane TC of 23.7 Wm-1 K-1 and a remarkably low compressive modulus of 4.85 MPa. Furthermore, the exceptional properties of composites, including low thermal resistance and high resilience rate, make them a reliable and durable option for various applications. Practical tests demonstrate their outstanding heat dissipation performance, significantly reducing CPU temperatures in a computer cooling system. This research work unveils the possible upper limit of TC in BN-based TIMs and paves the way for their large-scale practical implementation, particularly in the thermal management of next-generation electronic devices.
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Stenotrophomonas maltophilia J2, a highly efficient pyridine-degrading bacterium, was isolated from the aerobic tank of a pesticide-contaminated wastewater treatment plant. The strain J2 demonstrated an impressive pyridine degradation rate of 98.34% ± 0.49% within 72 h, at a pyridine concentration of 1100 mg·L-1, a temperature of 30 °C, a pH of 8.0, and a NaCl concentration of 0.5%. Notably, two new pyridine metabolic intermediates, 1,3-dihydroxyacetone and butyric acid, were discovered, indicating that J2 may degrade pyridine through two distinct metabolic pathways. Furthermore, the immobilized strain J2 was obtained by immobilizing J2 with biochar derived from the stem of Solidago canadensis L. In the pyridine-contaminated wastewater bioremediation experiment, the immobilized strain J2 was able to remove 2000 mg·L-1 pyridine with a 98.66% ± 0.47% degradation rate in 24 h, which was significantly higher than that of the control group (3.17% ± 1.24%), and remained above 90% in subsequent cycles until the 27th cycle. High-throughput sequencing analysis indicated that the J2 +B group had an elevated relative abundance of bacteria and functional genes that could be associated with the degradation of pyridine. The results offer a foundation for the effective use of immobilized strain in the treatment of recalcitrant pyridine-contaminated wastewater.
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Stenotrophomonas maltophilia , Aguas Residuales , Stenotrophomonas maltophilia/metabolismo , Biodegradación Ambiental , Bacterias/metabolismo , Piridinas/metabolismoRESUMEN
With the rapid development of the electronics industry, there is a growing demand for packaging materials that possess both high thermal conductivity (TC) and low electrical conductivity (EC). However, traditional insulating fillers such as boron nitride, aluminum nitride, and alumina (Al2O3) have relatively low intrinsic TC. When graphene, which exhibits both superhigh TC and EC, is used as a filler to fill epoxy resin, the TC of blends can be much higher than that of blends containing more traditional fillers. However, the high EC of graphene limits its application in cases where electrical insulation is required. To address this challenge, a method for coating graphene sheets with an in situ grown Al2O3 layer has been proposed for the fabrication of epoxy-based composites with both high TC and low EC. In the presence of a cationic surfactant, a dense Al2O3 layer with a network structure can be formed on the surface of graphene sheets. When the total content of Al2O3 and graphene mixed filler reached 30 wt%, the TC of the epoxy composite reached 0.97 W m-1 K-1, while the EC remained above 1011 Ω·cm. Finite element simulations accurately predicted TC and EC values in accordance with experimental results. This material, with its combination of high TC and good insulation properties, exhibits excellent potential for microelectronic packaging applications.
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Microbial consortia HY3 and JY3 with high degradation efficiency of 2-Diethylamino-4-hydroxy-6-methylpyrimidine (DHMP) were isolated from aerobic and parthenogenic ponds of DHMP-containing pharmaceutical wastewater, respectively. Both consortia were enriched and reached stable degradation performance with a DHMP concentration of 1500 mg L-1. The DHMP degradation efficiencies of HY3 and JY3 were 95.66% ± 0.24% and 92.16% ± 2.34% under the condition of shaking at 180 r·min-1 and the temperature of 30 °C for 72 h. And the removal efficiencies of chemical oxygen demand were 89.14% ± 4.78% and 80.30% ± 11.74%, respectively. High-throughput sequencing results indicated that three bacterial phyla of Proteobacteria, Bacteroidetes, and Actinobacteria were dominant in both HY3 and JY3, but their dominances varied. At the genus level, the richness of Unclassified Comamonadaceae (34.23%), Paracoccus (14.75%), and Brevundimonas (13.94%) ranked top three in HY3 whereas Unclassified Comamonadaceae (40.80%), Unclassified Burkholderiales (13.81%) and Delftia (13.11%) were dominant in JY3. The metabolites of DHMP degradation by HY3 and JY3 were analyzed in detail. Two pathways for cleavage of the nitrogenous heterocyclic ring were speculated, one of which was identified for the first time in this study.
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Compuestos Heterocíclicos , Aguas Residuales , Consorcios Microbianos , Bacterias , Compuestos Heterocíclicos/metabolismo , Preparaciones Farmacéuticas/metabolismo , Reactores Biológicos/microbiologíaRESUMEN
Asymmetric competition occurs when some species have distinct advantages over their competitors and is common in animals with overlapping habitats and diet. However, the mechanism allowing coexistence between asymmetric competitors is not fully clear. Chinese white-bellied rats (Niviventer confucianus, CWR) and Korean field mice (Apodemus peninsulae, KFM) are common asymmetric competitors in shrublands and forests west of Beijing city. They share similar diet (e.g. plant seeds) and activity (nocturnal), but differ in body size (CWR are bigger than KFM), food hoarding habit (CWR: mainly larder hoarding; KFM: both larder and scatter hoarding), and ability to protect cached food (CWR are more aggressive than KFM). Here, we tested seed competition in 15 CWR-KFM pairs over a 10-day period under semi-natural enclosure conditions to uncover the differences in food hoarding, cache pilferage, and food protection between the 2 rodents, and discuss the implication for coexistence. Prior to pilferage, CWR harvested and ate more seeds than KFM. CWR tended to larder hoard seeds, whereas KFM preferred to scatter hoard seeds. Following pilferage, CWR increased consumption, decreased intensity of hoarding, and pilfered more caches from KFM than they lost, while KFM increased consumption more than they hoarded, and they preferred to hoard seeds in low and medium competition areas. Accordingly, both of the 2 rodent species increased their total energy consumption and hoarding following pilferage. Both rodent species tended to harvest seeds from the source, rather than pilfer caches from each other to compensate for cache loss via pilferage. Compared to CWR, KFM consumed fewer seeds when considering seed number, but hoarded more seeds when considering the seeds' relative energy (energy of hoarded seeds/rodent body mass2/3 ) at the end of the trials. These results suggest that asymmetric competition for food exists between CWR and KFM, but differentiation in hoarding behavior could help the subordinate species (i.e. KFM) hoard more energy than the dominant species (i.e. CWR), and may contribute to their coexistence in the field.
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Acaparamiento , Roedores , Animales , Semillas , Conducta Alimentaria , Ecosistema , Murinae , ArvicolinaeRESUMEN
During the growth season, jujube trees are susceptible to infestation by the leaf mite, which reduces the fruit quality and productivity. Traditional monitoring techniques for mites are time-consuming, difficult, subjective, and result in a time lag. In this study, the method based on a particle swarm optimization (PSO) algorithm extreme learning machine for estimation of leaf chlorophyll content (SPAD) under leaf mite infestation in jujube was proposed. Initially, image data and SPAD values for jujube orchards under four severities of leaf mite infestation were collected for analysis. Six vegetation indices and SPAD value were chosen for correlation analysis to establish the estimation model for SPAD and the vegetation indices. To address the influence of colinearity between spectral bands, the feature band with the highest correlation coefficient was retrieved first using the successive projection algorithm. In the modeling process, the PSO correlation coefficient was initialized with the convergent optimal approximation of the fitness function value; the root mean square error (RMSE) of the predicted and measured values was derived as an indicator of PSO goodness-of-fit to solve the problems of ELM model weights, threshold randomness, and uncertainty of network parameters; and finally, an iterative update method was used to determine the particle fitness value to optimize the minimum error or iteration number. The results reflected that significant differences were observed in the spectral reflectance of the jujube canopy corresponding with the severity of leaf mite infestation, and the infestation severity was negatively correlated with the SPAD value of jujube leaves. The selected vegetation indices NDVI, RVI, PhRI, and MCARI were positively correlated with SPAD, whereas TCARI and GI were negatively correlated with SPAD. The accuracy of the optimized PSO-ELM model (R 2 = 0.856, RMSE = 0.796) was superior to that of the ELM model alone (R 2 = 0.748, RMSE = 1.689). The PSO-ELM model for remote sensing estimation of relative leaf chlorophyll content of jujube shows high fault tolerance and improved data-processing efficiency. The results provide a reference for the utility of UAV remote sensing for monitoring leaf mite infestation of jujube.
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Orientation control of anisotropic one-dimensional (1D) and two-dimensional (2D) materials in solutions is of great importance in many fields ranging from structural materials design, the thermal management, to energy storage. Achieving fine control of vertical alignment of anisotropic fillers (such as graphene, boron nitride (BN), and carbon fiber) remains challenging. This work presents a universal and scalable method for constructing vertically aligned structures of anisotropic fillers in composites assisted by the expansion flow (using 2D BN platelets as a proof-of-concept). BN platelets in the silicone gel strip are oriented in a curved shape that includes vertical alignment in the central area and horizontal alignment close to strip surfaces. Due to the vertical orientation of BN in the central area of strips, a through-plane thermal conductivity as high as 5.65 W m-1 K-1 was obtained, which can be further improved to 6.54 W m-1 K-1 by combining BN and pitch-based carbon fibers. The expansion-flow-assisted alignment can be extended to the manufacture of a variety of polymer composites filled with 1D and 2D materials, which can find wide applications in batteries, electronics, and energy storage devices.
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The carbonylative transformation of ethylene oxide (EO) into methyl 3-hydroxypropionate (3-HPM) is a key process for the production of 1,3-propanediol (1,3-PDO), which is currently viewed as one of the most promising monomers and intermediates in polyester and pharmaceuticals industry. In this work, a homogeneous reaction system using commercial Co2(CO)8 was first studied for the carbonylation of EO to 3-HPM. The catalytic behavior was related to the electronic environment of N on aromatic rings of ligands, where N with rich electron density induced a stronger coordination with Co center and higher EO transformation. A reaction order of 2.1 with respect to EO and 0.3 with respect to CO was unraveled based on the kinetics study. The 3-HPM yield reached 91.2% at only 40°C by Co2(CO)8 coordinated with 3-hydroxypyridine. However, Co-containing colloid was formed during the reaction, causing the tough separation and impossible recycling of samples. Concerning the sustainable utilization, Co particles immobilized on pre-treated carbon nanotubes (Co/CNT-C) were designed via an in situ reduced colloid method. It is remarkable that unlike conventional Co/CNT, Co/CNT-C was highly selective toward the transformation of EO to 3-HPM with a specific rate of 52.2 mmol·g Co - 1 ·h - 1 , displaying a similar atomic efficiency to that of coordinated Co2(CO)8. After reaction, the supported Co/CNT-C catalyst could be easily separated from the liquid reaction mixture, leading to a convenient cyclic utilization.
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Exploring low-energy reaction pathway of catalytic biomass conversion can lead to wider application and the achievement of sustainability objectives. Since glucose dehydrogenation to gluconic acid and H2 is a cost-effective alternative to glucose oxidation, this study aims to elucidate its mechanism. The detection of lactone as an intermediate indicates that cyclic glucose reacts directly via its hemiacetal group-ring opening is not involved; that is, cyclic glucose is dehydrogenated to lactone, which is further hydrolyzed to gluconic acid. The source of hydrogen is confirmed to be from glucose and water by Isotope tracing analysis. Density function theory calculations demonstrate that Hemiacetal Dehydrogenation Pathway (this work) is less energy intensive than Ring-opening Oxidation Pathway (previous works). This study provides a new dehydrogenation strategy to produce gluconic acid and H2 from biomass under mild conditions.
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Glucosa , Hidrógeno , Gluconatos , Glucosa/metabolismo , LactonasRESUMEN
Extrusion-based three-dimensional (3D) printing techniques usually exhibit anisotropic thermal, mechanical, and electric properties due to the shearing-induced alignment during extrusion. However, the transformation from the extrusion to stacking process is always neglected and its influence on the final properties remains ambiguous. In this work, we adopt two different sized boron nitride (BN) sheets, namely, small-sized BN (S-BN) and large-sized BN (L-BN), to explore their impact on the orientation degree, morphology, and final anisotropic thermal conductivity (TC) of thermoplastic polyurethane (TPU) composites by fused deposition modeling. The transformation from one-dimensional axial alignment in the extruded filament to two-dimensional alignment (horizontal and vertical alignment) in the stacking filament of BN sheets is observed, and its impact on anisotropic TC in three directions is clarified. It is found that L-BN/TPU composites show a high TC of 6.45 W m-1 K-1 at 60 wt % BN content along the printing direction, while at a lower content (<40 wt %), S-BN/TPU composites exhibit a higher TC than L-BN/TPU composites. Effects of orientation, viscosity, and voids are comprehensively considered to elucidate such differences. Finally, heat dissipation tests demonstrate the great potential of 3D printed BN/TPU composites to be used in thermal management applications.
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At present, learning-based citrus blossom recognition models based on deep learning are highly complicated and have a large number of parameters. In order to estimate citrus flower quantities in natural orchards, this study proposes a lightweight citrus flower recognition model based on improved YOLOv4. In order to compress the backbone network, we utilize MobileNetv3 as a feature extractor, combined with deep separable convolution for further acceleration. The Cutout data enhancement method is also introduced to simulate citrus in nature for data enhancement. The test results show that the improved model has an mAP of 84.84%, 22% smaller than that of YOLOv4, and approximately two times faster. Compared with the Faster R-CNN, the improved citrus flower rate statistical model proposed in this study has the advantages of less memory usage and fast detection speed under the premise of ensuring a certain accuracy. Therefore, our solution can be used as a reference for the edge detection of citrus flowering.
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Citrus , Redes Neurales de la Computación , Algoritmos , Análisis por Conglomerados , Modelos EstadísticosRESUMEN
BACKGROUND: Understanding how island ecosystems change across habitats is a major challenge in ecological conservation under the conditions of habitat degradation. According to a 2-year investigation on Dong Island of the Paracel Islands, South China Sea, we assessed the roles of different habitats at the species level and community level of birds using topological and network analysis. RESULTS: In addition to the thousands of Sula sula (a large-sized arboreal seabird) inhabiting the forests, there were 56 other bird species were recorded, representing 23 families and 12 orders, ranging in habitats of wetlands, forests, shrublands, grasslands, and/or beaches. The bird-habitat network had high nestedness, and bird species showed obvious clustering distribution. Integrated topological and network analysis showed that wetlands had a high contribution to species diversity and network structure, and it was a cluster center of migrant birds. Forests and grasslands were species hub and connector respectively, and forests were also the key habitat for residents. Beaches and shrublands were peripherals. The loss of wetlands and forests will result in a sharp reduction of species richness, and even make the S. sula, and most of the resident birds, become locally extinct. CONCLUSIONS: These results suggest that the wetland and forest habitats on the focal island are key important for migrant birds and resident birds respectively, and therefore much more attention should be paid to conservation of the focal island ecosystems.
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Antozoos , Ecosistema , Animales , Aves , China , Bosques , HumanosRESUMEN
Efficient thermal transportation in a preferred direction is highly favorable for thermal management issues. The combination of 3D printing and two-dimensional (2D) materials such as graphene, BN, and so on enables infinite possibilities for hierarchically aligned structure programming. In this work, we report the formation of the asymmetrically aligned structure of graphene filled thermoplastic polyurethane (TPU) composites during 3D printing process. The as-printed vertically aligned structure demonstrates a through-plane thermal conductivity (TC) up to 12 W m-1 K-1 at 45 wt % graphene content, which is â¼8 times of that of a horizontally printed structure and surpasses many of the traditional particle reinforced polymer composites. The superior TC is mainly attributed to the anisotropic structure design that benefited from the preferable degree of orientation of graphene and the multiscale dense structure realized by finely controlling the printing parameters. Finite element method (FEM) confirms the essential impact of anisotropic TC design for highly thermal conductive composites. This study provides an effective way to develop 3D printed graphene-based polymer composites for scalable thermal-related applications such as battery thermal management, electric packaging, and so on.
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Trueperella pyogenes (T. pyogenes) is a common opportunistic pathogen of many livestock and play an important regulation role during multibacterial infection and interaction with the host by its primary virulence factor pyolysin (PLO). The purpose of this study was to investigate the regulation role of PLO which serve as a combinational pathogen with lipopolysaccharide (LPS) during endometritis. In this study, the expression of bioactive recombinant PLO (rPLO) in a prokaryotic expression system and its purification are described. Moreover, we observed that rPLO inhibited the innate immune response triggered by LPS and that methyl-ß-cyclodextrin (MBCD) abrogated this inhibitory effect in goat endometrium stromal cells (gESCs). Additionally, we show from pharmacological and genetic studies that rPLO-induced autophagy represses gene expression by inhibiting NLRP3 inflammasome activation. Importantly, this study reported that ATF6 serves as a primary regulator of the cellular inflammatory reaction to rPLO. Overall, these observations suggest that T. pyogenes PLO could create an immunosuppressive environment for other pathogens invasion by regulating cellular signaling pathways.
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Factor de Transcripción Activador 6/metabolismo , Autofagia/efectos de los fármacos , Proteínas Bacterianas/farmacología , Toxinas Bacterianas/farmacología , Endometrio/citología , Proteínas Hemolisinas/farmacología , Lipopolisacáridos/farmacología , Actinomycetaceae/patogenicidad , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Femenino , Cabras , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Inflamasomas/efectos de los fármacos , Inflamasomas/metabolismo , Inflamación , Mediadores de Inflamación/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismoRESUMEN
Early detection has the potential to reduce cancer mortality, but an effective screening test must demonstrate asymptomatic cancer detection years before conventional diagnosis in a longitudinal study. In the Taizhou Longitudinal Study (TZL), 123,115 healthy subjects provided plasma samples for long-term storage and were then monitored for cancer occurrence. Here we report the preliminary results of PanSeer, a noninvasive blood test based on circulating tumor DNA methylation, on TZL plasma samples from 605 asymptomatic individuals, 191 of whom were later diagnosed with stomach, esophageal, colorectal, lung or liver cancer within four years of blood draw. We also assay plasma samples from an additional 223 cancer patients, plus 200 primary tumor and normal tissues. We show that PanSeer detects five common types of cancer in 88% (95% CI: 80-93%) of post-diagnosis patients with a specificity of 96% (95% CI: 93-98%), We also demonstrate that PanSeer detects cancer in 95% (95% CI: 89-98%) of asymptomatic individuals who were later diagnosed, though future longitudinal studies are required to confirm this result. These results demonstrate that cancer can be non-invasively detected up to four years before current standard of care.
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ADN Tumoral Circulante/sangre , Detección Precoz del Cáncer/métodos , Neoplasias/sangre , Neoplasias/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , China , Metilación de ADN , Epigenómica , Femenino , Marcadores Genéticos , Voluntarios Sanos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
Superior species may have distinct advantages over subordinates within asymmetrical interactions among sympatric animals. However, exactly how the subordinate species coexists with superior species is unknown. In the forests west of Beijing City, intense asymmetrical interactions of food competition exist among granivorous rodents (e.g. Apodemus peninsulae, Niviventer confucianus, Sciurotamias davidianus and Tscherskia triton) that have broadly overlapping habitats and diets but have varied body size (range 15-300 g), hoarding habits (scatter vs larder) and/or daily rhythm (diurnal vs nocturnal). The smallest rodent, A. peninsulae, which typically faces high competitive pressure from larger rodents, is an ideal model to explore how subordinate species coexist with superior species. Under semi-natural enclosure conditions, we tested responses of seed-hoarding behavior in A. peninsulae to intraspecific and interspecific competitors in the situations of pre-competition (without competitor), competition (with competitor) and post-competition (competitor removed). The results showed that for A. peninsulae, the intensity of larder-hoarding increased and the intensity of scatter-hoarding declined in the presence of intraspecifics and S. davidianus, whereas A. peninsulae ceased foraging and hoarding in the presence of N. confucianus and T. triton. A. peninsulae reduced intensity of hoarding outside the nest and moved more seeds into the nest for larder-hoarding under competition from intraspecific individuals and S. davidianus. In most cases, the experimental animals could recover to their original state of pre-competition when competitors were removed. These results suggest that subordinate species contextually regulate their food-hoarding strategies according to different competitors, promoting species coexistence among sympatric animals that have asymmetrical food competition.
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Conducta Competitiva , Conducta Alimentaria , Roedores/fisiología , Animales , Tamaño Corporal , China , Ecosistema , Murinae/anatomía & histología , Murinae/fisiología , Roedores/anatomía & histología , Semillas , Especificidad de la EspecieRESUMEN
In the struggle for survival, scatter-hoarding rodents are known to cache food and pilfer the caches of others. The extent to which rodents utilize auditory/visual cues from conspecifics to improve cache-pilfering is unknown. Here, Siberian chipmunks (Tamias sibiricus) were allowed to search for caches of Corylus heterophylla seeds (man-made caches and animal-made caches) after experiencing cues from a conspecific's cache-searching events. For each type of cache, 3 experimental scenarios were presented: (1) alone (control); (2) auditory/visual (hearing and seeing conspecific's cache-searching events); and (3) auditory only (hearing conspecific's cache-searching events only) with random orders. The subjects located man-made caches faster, harvested more caches, and hoarded more seeds both in the auditory/visual and the auditory only treatments compared to the control, while scatter-hoarding more seeds in the auditory/visual treatment but larder-hoarding more seeds in the auditory only treatment. Compared to the control, the animals spent less time locating animal-made caches, harvested more caches, ate fewer seeds, larder-hoarded more seeds and hoarded more seeds in total both in the auditory/visual and the auditory only treatments, while eating more seeds and hoarded fewer seeds in total in the auditory only treatment than in the auditory/visual treatment. The results also show that females spent less time locating the animal-made caches, but they scatter-hoarded fewer seeds than males in the auditory/visual treatment. To the best of our knowledge, this is the first report that visual and/or auditory cues of conspecifics improve cache-pilfering and hoarding in rodents.
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Señales (Psicología) , Ambiente , Conducta Alimentaria/fisiología , Sciuridae/fisiología , Animales , Femenino , MasculinoRESUMEN
Effects of trimetazidine combined with berberine on endothelial function of patients with coronary heart disease combined with primary hypertension (CCP) were investigated. A total of 68 patients with CCP were selected from July 2014 to August 2016 to serve as observation group. At the same time, 68 healthy people were also selected to serve as control group (physiological saline). Expression of endothelial nitric oxide synthase (eNOS) mRNA in the blood samples of the observation and control groups before and after treatment was determined by RT-PCR. Levels of NO in the plasma of the observation and control groups before and after treatment were measured by nitric acid reductase method. Brachial artery flow-mediated vasodilation (FMD) of observation and control groups was detected by brachial artery ultrasonography before and after treatment. Before treatment, expression level of eNOS mRNA in blood of the observation group was significantly lower than that of the control group (P<0.05). After treatment, expression level of eNOS mRNA was significantly increased (P<0.05). Plasma NO content 41.06±3.63 mol/l in blood of the observation group was significantly lower than that of the control group 53.28±3.09 mol/l (P<0.05). After treatment with trimetazidine and berberine, level of NO 50.75±2.75 mol/l was significantly increased compared with the level before treatment (P<0.05). FMD value (5.03±0.95) was significantly lower in observation group than that in control group (16.04±1.63) (P<0.05). After treatment with trimetazidine and berberine, FMD value (14.02±2.39) was significantly increased compared with the level before treatment (P<0.05). The results suggested that the combination of trimetazidine and berberine can increase the content of NO in blood and promote endothelium-dependent dilation function of brachial arteries, which is helpful in the treatment of CCP.