Adaptive Response in Mice Exposed to 900 MHz Radiofrequency Fields: Primary DNA Damage

The phenomenon of adaptive response (AR) in animal and human cells exposed to ionizing radiation is well documented in scientific literature. We have examined whether such AR could be induced in mice exposed to non-ionizing radiofrequency fields (RF) used for wireless communications. Mice were pre-exposed to 900 MHz RF at 120 µW/cm2 power density for 4 hours/day for 1, 3, 5, 7 and 14 days and then subjected to an acute dose of 3 Gy γ-radiation. The primary DNA damage in the form of alkali labile base damage and single strand breaks in the DNA of peripheral blood leukocytes was determined using the alkaline comet assay. The results indicated that the extent of damage in mice which were pre-exposed to RF for 1 day and then subjected to γ-radiation was similar and not significantly different from those exposed to γ-radiation alone. However, mice which were pre-exposed to RF for 3, 5, 7 and 14 days showed progressively decreased damage and was significantly different from those exposed to γ-radiation alone. Thus, the data indicated that RF pre-exposure is capable of inducing AR and suggested that the pre-exposure for more than 4 hours for 1 day is necessary to elicit such AR

An overview of substrate stiffness guided cellular response and its applications in tissue regeneration

Cell-matrix interactions play a critical role in tissue repair and regeneration. With gradual uncovering of substrate mechanical characteristics that can affect cell-matrix interactions, much progress has been made to unravel substrate stiffness-mediated cellular response as well as its underlying mechanisms. Yet, as a part of cell-matrix interaction biology, this field remains in its infancy, and the detailed molecular mechanisms are still elusive regarding scaffold-modulated tissue regeneration. This review provides an overview of recent progress in the area of the substrate stiffness-mediated cellular responses, including 1) the physical determination of substrate stiffness on cell fate and tissue development; 2) the current exploited approaches to manipulate the stiffness of scaffolds; 3) the progress of recent researches to reveal the role of substrate stiffness in cellular responses in some representative tissue-engineered regeneration varying from stiff tissue to soft tissue. This article aims to provide an up-to-date overview of cell mechanobiology research in substrate stiffness mediated cellular response and tissue regeneration with insightful information to facilitate interdisciplinary knowledge transfer and enable the establishment of prognostic markers for the design of suitable biomaterials

Ongoing evolution of response assessment in glioma: Where do we stand?

The investigation and development of recently introduced agents or radiological measurements caused emergent misunderstandings to the response assessment of glioma. To date, the classical Macdonald criteria and the response assessment of neuro-oncology (RANO) criteria have been used successively for the evaluation of glioma outcome. However, ongoing efforts on complementary assessments are necessary to combat this malignancy. In this review, we highlight the shortcomings of the current criteria and introduce the initiative effort of RANO guideline and its offspring. We also discuss some future barriers for accurate assessment of treatment response in glioma

In situ electrospun aloe-nanofiber membrane for chronic wound healing

Alleviating excessive inflammation while accelerating chronic wound healing to prevent wound infection has remained challenging, especially during the coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 when patients experienced difficulties with receive appropriate healthcare. We addressed this issue by developing handheld electrospun aloe-nanofiber membranes (ANFMs) with convenient, environmentally friendly properties and a therapeutic capacity for wound closure. Our results showed that ANFMs fabricated with high molecular weight polyvinyl alcohol (PVA) to form fibers during electrospinning had uniform fibrous architecture and a porous structure. Given the value of aloe gel in accelerating wound healing, liquid extracts from ANFMs significantly downregulated the expression of the pro-inflammatory genes, interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS), and markedly suppress the generation of reactive oxygen species (ROS) induced by lipopolysaccharide in RAW264.7 macrophages. These results indicated the excellent antioxidant and anti-inflammatory effects of ANFMs. After implantation into a mouse diabetic wound model for 12 days in situ, ANFMs notably expedited chronic wound healing via promoting angiogenesis and enhancing cell viability. Our ANFMs generated by handheld electrospinning in situ healed chronic wounds offer a convenient and promising alternative for patients to heal their own wounds under variable conditions

Overview of Injectable Hydrogels for the Treatment of Myocardial Infarction

Myocardial infarction (MI) triggers adverse remodeling mechanisms, thus leading to heart failure. Since the application of biomaterial-based scaffolds emerged as a viable approach for providing mechanical support and promoting cell growth, injectable hydrogels have garnered substantial attention in MI treatment because of their minimally invasive administration through injection and diminished risk of infection. To fully understand the interplay between injectable hydrogels and infarcted myocardium repair, this review provides an overview of recent advances in injectable hydrogel-mediated MI therapy, including: I) material designs for repairing the infarcted myocardium, considering the pathophysiological mechanism of MI and design principles for biomaterials in MI treatment; II) the development of injectable functional hydrogels for MI treatment, including conductive, self-healing, drug-loaded, and stimulus-responsive hydrogels; and III) research progress in using injectable hydrogels to restore cardiac function in infarcted myocardium by promoting neovascularization, enhancing cardiomyocyte proliferation, decreasing myocardial fibrosis, and inhibiting excessive inflammation. Overall, this review presents the current state of injectable hydrogel research in MI treatment, offering valuable information to facilitate interdisciplinary knowledge transfer and enable the development of prognostic markers for suitable injectable materials

Modeling of Soil Water and Salt Dynamics and Its Effects on Root Water Uptake in Heihe Arid Wetland, Gansu, China

In the Heihe River basin, China, increased salinity and water shortages present serious threats to the sustainability of arid wetlands. It is critical to understand the interactions between soil water and salts (from saline shallow groundwater and the river) and their effects on plant growth under the influence of shallow groundwater and irrigation. In this study, the Hydrus-1D model was used in an arid wetland of the Middle Heihe River to investigate the effects of the dynamics of soil water, soil salinization, and depth to water table (DWT) as well as groundwater salinity on Chinese tamarisk root water uptake. The modeled soil water and electrical conductivity of soil solution (ECsw) are in good agreement with the observations, as indicated by RMSE values (0.031 and 0.046 cm3·cm−3 for soil water content, 0.037 and 0.035 dS·m−1 for ECsw, during the model calibration and validation periods, respectively). The calibrated model was used in scenario analyses considering different DWTs, salinity levels and the introduction of preseason irrigation. The results showed that (I) Chinese tamarisk root distribution was greatly affected by soil water and salt distribution in the soil profile, with about 73.8% of the roots being distributed in the 20–60 cm layer; (II) root water uptake accounted for 91.0% of the potential maximal value when water stress was considered, and for 41.6% when both water and salt stress were considered; (III) root water uptake was very sensitive to fluctuations of the water table, and was greatly reduced when the DWT was either dropped or raised 60% of the 2012 reference depth; (IV) arid wetland vegetation exhibited a high level of groundwater dependence even though shallow groundwater resulted in increased soil salinization and (V) preseason irrigation could effectively increase root water uptake by leaching salts from the root zone. We concluded that a suitable water table and groundwater salinity coupled with proper irrigation are key factors to sustainable development of arid wetlands

Sepsis-induced impairment of neutrophil chemotaxis on a microfluidic chip

This study aimed to design a microfluidic chip to measure neutrophil chemotaxis, which is a convenient assay to assess the severity and prognosis of sepsis, and to study the mechanisms involved in the variation of neutrophil chemotaxis. Neutrophil chemotaxis was investigated in this microfluidic device by measuring the migration speed of neutrophils following the LPS concentration gradient stimulus. Neutrophils of 32 sepsis patients were divided into three groups according to the seriousness of physician-diagnosed sepsis, and 12 healthy individuals served as controls. Statistical significance was set at an alpha value of P<0.05. Neutrophil chemotaxis was significantly decreased following the seriousness of sepsis. By contrast, in septic neutrophils, the expression of TLR2 was significantly increased, whereas the expression of CXCR2 was significantly decreased. Neutrophil chemotaxis in sepsis was significantly reduced as compared to healthy individuals. We speculated that impaired neutrophil chemotaxis in sepsis was probably mediated by the TLR2-CXCR2 pathway. (C) 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved