Glioblastoma behavior study under different frequency electromagnetic field.

The tumor-treating fields (TTFields) technology has revolutionized the management of recurrent and newly diagnosed glioblastoma (GBM) cases. To ameliorate this treatment modality for GBM and other oncological conditions, it is necessary to understand the biophysical principles of TTFields better. In this study, we further analyzed the mechanism of the electromagnetic exposure with varying frequencies and electric field strengths on cells in mitosis, specifically in telophase. In reference to previous studies, an intuitive finite element model of the mitotic cell was built for electromagnetic simulations, predicting a local increase in the cleavage furrow region, which may help explain TTFields' anti-proliferative effects. Cell experiments confirmed that the reduction in proliferation and migration of glioma cell by TTFields was in a frequency- and field-strength-dependent manner. This work provides unique insights into the selection of frequencies in the anti-proliferative effect of TTFields on tumors, which could improve the application of TTFields.

Contrasting Responses of Multispatial Soil Fungal Communities of Thuja sutchuenensis Franch., an Extremely Endangered Conifer in Southwestern China.

Thuja sutchuenensis Franch. is an endangered species in southwest China, distributed sporadically in mountainous areas. Soil property and soil fungal community play a crucial role in plant growth and survival. Nevertheless, understanding soil properties and the soil fungal community in the areas where T. sutchuenensis is distributed is extremely limited. Hence, this study collected a total of 180 soil samples from five altitudinal distribution areas (altitudinal gradients) and three vertical depths throughout four horizontal distances from the base of each tree. The results found that altitudinal gradients and vertical depths altered soil properties, including pH, organic matter content, water content, total nitrogen, phosphorus, and potassium, and available nitrogen, phosphorus, and potassium. The fungal alpha diversity indexes (Chao1 and Shannon) and beta diversity were dramatically decreased with elevation. In addition, high altitudes (2,119 m) harbored the highest relative abundance of ectomycorrhizal fungi (27.57%) and the lowest relative abundance of plant-pathogenic fungi (1.81%). Meanwhile, we identified a series of fungal communities, such as Tomentella, Piloderma, Cortinarius, Sebacina, and Boletaceae, that play an essential role in the survival of T. sutchuenensis. The correlation analysis and random forest model identified that water content and total phosphorus showed strong relationships with fungal characteristics and were the primary variables for Zygomycota and Rozellomycota. Collectively, the findings of this integrated analysis provide profound insights into understanding the contrasting responses of T. sutchuenensis soil fungal communities and provide a theoretical basis for T. sutchuenensis habitat restoration and species conservation from multispatial perspectives. IMPORTANCE The present study highlights the importance of fungal communities in an endangered plant, T. sutchuenensis. Comparative analysis of soil samples in nearly all extant T. sutchuenensis populations identified that soil properties, especially soil nutrients, might play critical roles in the survival of T. sutchuenensis. Our findings prove that a series of fungal communities (e.g., Tomentella, Piloderma, and Cortinarius) could be key indicators for T. sutchuenensis survival. In addition, this is the first time that large-scale soil property and fungal community investigations have been carried out in southwest China, offering important values for exploring the distribution pattern of regional soil microorganisms. Collectively, our findings display a holistic picture of soil microbiome and environmental factors associated with T. sutchuenensis.

Comparative Analyses of Rhizosphere Bacteria Along an Elevational Gradient of Thuja sutchuenensis.

Thuja sutchuenensis Franch. is an endangered species in southwestern China, primarily distributed in 800-2,100 m of inaccessible mountainous areas. Rhizosphere soil physicochemical properties and bacterial communities play an essential role in managing plant growth and survival. Nonetheless, the study investigating rhizosphere soil properties and bacterial communities of T. sutchuenensis is limited. The present study investigated soil properties, including soil pH, organic matter, water content, nitrogen, phosphorus, and potassium contents, and bacterial communities in nearly all extant T. sutchuenensis populations at five elevational gradients. Our results demonstrated that the increase in elevation decreased rhizosphere and bulk soil phosphorus content but increased potassium content. In addition, the elevational gradient was the dominant driver for the community composition differentiation of soil bacterial community. Proteobacteria and Acidobacteria were the dominant bacterial phyla distributed in the rhizosphere and bulk soils. Co-occurrence network analysis identified key genera, including Bradyrhizobium, Acidicapsa, Catenulispora, and Singulisphaera, that displayed densely connected interactions with many genera in the rhizosphere soil. The dominant KEGG functional pathways of the rhizosphere bacteria included ABC transporters, butanoate metabolism, and methane metabolism. Further correlation analysis found that soil phosphorus and potassium were the dominant drivers for the diversity of soil bacteria, which were distinctively contributed to the phylum of Planctomycetes and the genera of Blastopirellula, Planctomycetes, and Singulisphaera. Collectively, this comprehensive study generated multi-dimensional perspectives for understanding the soil bacterial community structures of T. sutchuenensis, and provided valuable findings for species conservation at large-scale views.

CuInS2/ZnS QD exposure induces developmental toxicity, oxidative stress and DNA damage in rare minnow (Gobiocypris rarus) embryos and larvae.

Chinese rare minnow (Gobiocypris rarus) embryos were used as an experimental model to investigate the effects of CuInS2/ZnS quantum dots (QDs) on the early life stages of G. rarus. Normal developmental parameters (survival rate, body length and average heart rate), biomarker genes [stress response (Hsp70), detoxification (Cyp1a), organizer function and axis formation (Wnt8α), and muscle (Mstn)], enzymatic activity and DNA damage were recorded as endpoints in the developing embryos/larvae after exposure until 96h post-fertilization (hpf). Reduced survival rate, decreased heart rate, altered body length, increased malformation rate, decreased hatching rate, advanced hatching time in response to low concentrations (50 and 100nmol/L) and delayed hatching time in response to high concentrations were observed after exposure, as were many other toxic effects, including pericardial edema and bent tails. The 72 hpf LC50 (median lethal concentration) was determined to be 624.364nmol/L. Treatment with certain concentrations of CuInS2/ZnS QDs significantly increased the superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels and significantly induced DNA damage. After treatment with CuInS2/ZnS QDs, the embryos showed highly up-regulated expression of Hsp70, Cyp1a and Wnt8a and significantly up-regulated expression of Mstn at 12 hpf. Overall, this study indicates that CuInS2/ZnS QDs are potentially toxic to G. rarus embryos. The information presented in this study will be helpful for fully understanding the toxicity induced by CuInS2/ZnS QDs in fish embryos.

[Enhanced Short-cut Denitrification by Fe(0)-activated Carbon and Its Influencing Factors].

In order to reduce the carbon source for biological short-cut denitrification, Fe(0)-activated carbon was used to enhance nitrogen removal in the absence of organic carbon, and the influences of the Fe/C mass ratio and initial pH value on the nitrogen removal efficiency were explored. The results showed that the nitrite removal efficiency increased from 7.4% to 31.1% when the Fe(0)-activated carbon was used to enhance short-cut denitrification. When the Fe/C mass ratio was reduced from 2:1 to 1:1 and 1:2, both the denitrification rate and nitrite removal efficiency first increased and then decreased. At a Fe/C mass ratio of 1:1, a maximum denitrification rate of 5.58 mg·(g·h)-1 and a maximum nitrite removal efficiency of 41.1% were achieved, respectively, and 0.1 mg of nitrous oxide was emitted. When the pH value was increased from 6.0 to 9.0, the denitrification rate decreased from 7.39 to 5.96 mg·(g·h)-1, and the nitrous oxide emission decreased from 0.19 to 0.12 mg. Therefore, a higher nitrogen removal efficiency could be achieved by Fe(0)-activated at a Fe/C mass ratio of 1:1 and pH value of 6.0. However, more nitrous oxide would be emitted at a low pH value.

Developmental Toxicity of Carbon Quantum Dots to the Embryos/Larvae of Rare Minnow (Gobiocypris rarus).

The toxic effects of CDs on rare minnow (Gobiocypris rarus) embryos at different developmental stages were investigated. The results showed that rare minnow embryos had decreased spontaneous movements, body length, increased heart rate, pericardial edema, yolk sac edema, tail/spinal curvature, various morphological malformations, and decreased hatching rate. Biochemical analysis showed the CDs exposure significantly inhibited the activity of Na+/K+-ATPase and Ca2+-ATPase and increased the MDA contents and the activity of SOD, CAT, and GPX. Further examination suggested that the CDs exposure induced serious embryonic cellular DNA damage. Moreover, the CDs exposure induced upregulation of development related genes (Wnt8a and Mstn) along with the downregulation of Vezf1. Overall, the present study revealed that the CDs exposure has significant development toxicity on rare minnow embryos/larvae. Mechanistically, this toxicity might result from the pressure of induced oxidative stress coordinate with the dysregulated development related gene expression mediated by the CDs exposure.