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The identification of rapid, sensitive and high-throughput biomarkers is imperative in order to identify individuals harmed by radiation accidents, and accurately evaluate the absorbed doses of radiation. DNA microarrays have previously been used to evaluate the alterations in growth/differentiation factor 15 (GDF15) gene expression in AHH-1 human lymphoblastoid cells, following exposure to γ-rays. The present study aimed to characterize the relationship between the dose of ionizing radiation and the produced effects in GDF-15 gene expression in AHH-1 cells and human peripheral blood lymphocytes (HPBLs). GDF-15 mRNA and protein expression levels following exposure to γ-rays and neutron radiation were assessed by reverse transcription-quantitative polymerase chain reaction and western blot analysis in AHH-1 cells. In addition, alterations in GDF-15 gene expression in HPBLs following ex vivo irradiation were evaluated. The present results demonstrated that GDF-15 mRNA and protein expression levels in AHH-1 cells were significantly upregulated following exposure to γ-ray doses ranging between 1 and 10 Gy, regardless of the dose rate. A total of 48 h following exposure to neutron radiation, a dose-response relationship was identified in AHH-1 cells at γ-ray doses between 0.4 and 1.6 Gy. GDF-15 mRNA levels in HPBLs were significantly upregulated following exposure to γ-ray doses between 1 and 8 Gy, within 4–48 h following irradiation. These results suggested that significant time- and dose-dependent alterations in GDF-15 mRNA and protein expression occur in AHH-1 cells and HPBLs in the early phases following exposure to ionizing radiation. In conclusion, alterations in GDF-15 gene expression may have potential as a biomarker to evaluate radiation exposure.

Nitrocellulose liquid bandage (L-Bandage) is extensively used in hard-to-cover cuts and wounds management, owing to its flexibility, softness, transparency, and conformability. However, evidence supporting their mechanisms of action as wound dressing is scanty. This study introduces a novel nano-porous L-Bandage, and provides results from a mouse full-thickness wound model investigating its mechanism of action on wound healing. Different characteristics, such as porosity, mechanical properties and water vapor transmission rate (WVTR) were determined. The L-Bandage formed film had a porous network structure with mean diameter of 18 nm that could effectively prevent the bacterial invasion, and favorable properties of tensile strength, elongation, and WVTR. The L-Bandage treated wound exhibited accelerated healing, with reduced inflammations, enhanced wound re-epithelialization, contraction, granulation tissue formation, and rapid angiogenesis. Our data suggested that L-Bandage could serve as a promising wound dressing, because of its desirable properties for wound healing.

Connexin43 has been shown to play a pivotal role in wound healing process. Wound repair is enhanced by acute downregulation of connexin43, by increasing proliferation and migration of keratinocyte and fibroblast. Angiogenesis is also a central feature of wound repair, but little is known about the effects of connexin43 modulation on functions of endothelial cells. We used connexin43 specific small interference RNA (siRNA) to reduce the expression of connexin43 in human umbilical vein endothelial cell (HUVEC), and investigated the effects of connexin43 downregulation on intercellular communication, viability, proliferation, migration and angiogenic activity of HUVEC. Treatment of siRNA markedly reduced the expression of connexin43 by -80% in HUVEC (P0.05), and decreased the intercellular communication by -65% (P0.05). The viability, proliferation, migration and angiogenic activity of HUVEC decreased significantly (P0.05), compared with that of the normal cells. The results suggest that temporally downregulation of connexin43 expression at early stage of wound to inhibit the abnormal angiogenesis characterized with leaky and inflamed blood vessels, maybe a prerequisite for coordinated normal healing process.