Effects of Hydroxyapatite Nanoparticles on Apoptosis and Invasion of Human Renal Cell Carcinoma 786-0 Cells

Renal cell carcinoma is the most common cancer of the kidney, and resistant to traditional therapies. The aim of this study is to investigate the effects of hydroxyapatite nanoparticles on human renal cell carcinoma 786-0 cells. Cell proliferation was assessed with an 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide(MTT) staining kit. The apoptosis assay was assessed with an FITC Annexin V Apoptosis Detection Kit. Caspase-3 and caspase-12 were detected by immunocytochemical staining and semi-qua...     

Effect of prey-taxis on predator’s invasion in a spatially heterogeneous environment

In this study, we consider a diffusive predator–prey system with prey-taxis and ratio-dependent functional responses in a spatially heterogeneous environment. Prey-taxis implies that the predator exhibits directed movement in the presence of prey. We claim that when the predator diffuses uniformly without prey-taxis, only the diffusion of the species plays a role in the predator’s invasion in a spatially homogeneous environment. However, when the predator disperses through uniform diffusion together with prey-taxis, we observe that both the diffusion of species and prey-taxis affect the invasion of the predator, which is not the case in a spatially homogeneous environment. The results are obtained by investigating the local stability of a semi-trivial solution, using an eigenvalue analysis.     

MicroRNA-143对人乳腺癌MCF-7细胞侵袭和迁移的影响

目的探讨microRNA-143（miR-143）对人乳腺癌MCF-7细胞侵袭、迁移和增殖的影响。方法在脂质体介导下将miR-143抑制剂（miR-143 inhibitors）转染入MCF-7细胞，以inhibitor negative control（inhibitor NC）作为阴性对照。通过MTS试剂盒检测细胞增殖能力，以Transwel 侵袭实验和迁移实验分别检测细胞侵袭能力和迁移能力。结果（1）miR-143 inhibitors组与inhibitor NC组间细胞增殖活性无明显差异（P＞0.05）；（2）Transwel 侵袭及迁移实验显示转染miR-143 inhibitors后，MCF-7细胞的侵袭及迁移能力均明显增强（P＜0.05）。结论 miR-143对人乳腺癌MCF-7细胞的侵袭及迁移能力存在负性调控作用，可能成为乳腺癌治疗的潜在靶点。     

A Biomimetic Escape Strategy for Cytoplasm Invasion by Synthetic Particles

The translocation of nanomaterials or complex delivery systems into the cytosol is a major challenge in nanobiotechnology. After receptor‐mediated endocytosis, most nanomaterials are sequestered and undergo degradation, therapy inactivation, or exocytosis. Herein we explore a novel surface particle coating made of adsorbed carbon nanotubes that provides coated materials with new properties that reproduce the viral cell‐invasive mechanisms, namely, receptor‐mediated endocytosis, endolysosomal escape, and cytosolic particle release preserving cell viability. This novel biomimetic coating design will enable the intracytoplasmic delivery of many different functional materials endowed with therapeutic, magnetic, optical, or catalytic functionalities, thus opening the door to a wide array of chemical and physical processes within the cytosolic or nuclear domains, and supporting new developments in the biotechnological, pharmaceutical, and biomedical industries.     

Predator invasion in predator–prey model with prey-taxis in spatially heterogeneous environment

We consider a predator–prey model with prey-taxis and Holling-type II functional responses in a spatially heterogeneous environment to analyze the effects of prey-taxis and the heterogeneity of an environment on predator invasion. To achieve our goal, we investigate the stability of semi-trivial solution in which the predator is absent. It is known that both the predator diffusion and the death rate contribute to the predator invasion in a heterogeneous habitat when there is no prey-taxis. In this paper, we show that predator invasion is affected by the prey-taxis and diffusions of the prey-taxis model for a certain range of predator death rates in a heterogeneous environment. Furthermore, in cases where predator invasion by predator diffusion does not occur in a particular death rate range of the predator, predator invasion can occur by prey-taxis in a spatially heterogeneous habitat. In addition, we compare this phenomenon to the corresponding predator–prey model with ratio-dependent functional responses. It is observed that none of the predator’s diffusion and prey-taxis affect the predator’s invasion, and that only the predator’s death rate contributes to predator invasion for the model with ratio-dependent functional responses.     

How do dispersal rates affect the transition from periodic to irregular spatio-temporal oscillations in invasive predator–prey systems?

When one considers the spatial aspects of a cyclic predator–prey interaction, ecological events such as invasions can generate periodic travelling waves (PTWs)—sometimes known as wavetrains. In certain instances PTWs may destabilise into spatio-temporal irregularity due to convective type instabilities, which permit a fixed width band of PTWs to develop behind the propagating invasion front. In this paper, we detail how one can locate this transition when one has unequal predator and prey dispersal rates. We do this by using absolute stability theory combined with a recent derivation of the amplitude of PTWs behind invasion. This work is applicable to a wide range of reaction–diffusion type predator–prey models, but in this paper we apply it to a specific set of equations (the Leslie–May model). We show that the width of PTW band increases/decreases when the ratio of prey and predator dispersal rates is large/small.     

Belowground feedbacks as drivers of spatial self-organization and community assembly

Vegetation patterning in water-limited and other resource-limited ecosystems highlights spatial self-organization processes as potentially key drivers of community assembly. These processes provide insight into predictable landscape-level relationships between organisms and their abiotic environment in the form of regular and irregular patterns of biota and resources. However, two aspects have largely been overlooked; the roles played by plant – soil-biota feedbacks and allelopathy in spatial self-organization, and their potential contribution, along with plant-resource feedbacks, to community assembly through spatial self-organization. Here, we expand the drivers of spatial self-organization from a focus on plant-resource feedbacks to include plant – soil-biota feedbacks and allelopathy, and integrate concepts of nonlinear physics and community ecology to generate a new hypothesis. According to this hypothesis, below-ground processes can affect community assemblages through two types of spatial self-organization, global and local. The former occurs simultaneously across whole ecosystems, leading to self-organized patterns of biota, allelochemicals and resources, and niche partitioning. The latter occurs locally in ecotones, and determines ecotone structure and motion, invasion dynamics, and species coexistence. Studies of the two forms of spatial self-organization are important for understanding the organization of plant communities in drier climates which are likely to involve spatial patterning or re-patterning. Such studies are also important for developing new practices of ecosystem management, based on local manipulations at ecotones, to slow invasion dynamics or induce transitions from transitive to intransitive networks of interspecific interactions which increase species diversity.