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Purpose UVB exposure accelerates skin aging and age-associated pigmentation, but their relationship remains unclear. UVB induces premature senescence and melanin production within melanocytes, along with the upregulation of p53 and cellular tyrosinase (TYR). As a tumor suppressor gene, p53 can keep the genome intact by modulating cell apoptosis and growth arrest during DNA injury. It is also associated with age-associated pigmentation, directly or indirectly regulating pigment-related gene expression. Melatonin effectively regulates tyrosinase activity and resists aging. In this study, we investigated the regulation of p53 on TYR to understand the association between premature senescence and senescence-associated pigmentation and determine the mechanism by which melatonin affects UVB-stimulated melanin production. Methods Primary melanocytes were extracted and identified from the male foreskin. The primary melanocytes were transduced using lentivirus pLKD-CMV-EGFP-2A-Puro-U6-TYR to knock down TYR expression. The melanin content was determined using the NaOH method, 3,4-Dihydroxy-L-phenylalanine (L-DOPA) was oxidized to dopachrome to determine TYR activity, and Western blotting was performed to detect the level of TYR protein. The primary melanocytes were pretreated with Nutlin-3 or PFT-α to upregulate or downregulate p53 levels or melatonin for 12 h and exposed to UVB irradiation at 80 mJ/cm2. The senescence-associated beta-galactosidase (SA-β-gal) kit was used to analyze premature senescence. The levels of p53, p-p53, and TYR protein were detected by performing the automated capillary electrophoresis Western blotting analysis in melanocytes 72 h after UVB irradiation. Wild-type and TYR(–/–) or TYR(+/–) knockout C57BL/6J mice were used to determine the regulatory role of TYR on melanin synthesis in vivo. Additionally, the effect of melatonin on skin erythema and pigmentation induced by UVB irradiation was analyzed in vivo. Results Primary melanocytes turned deep black after L-DOPA staining, indicating higher TYR protein and mRNA expression. Tyrosinase activity and melanin levels induced by UVB irradiation decreased significantly after the primary melanocytes were infected with pLKD-CMV-EGFP-2A-Puro-U6-TYR (P P TYR(–/–) knockout mice were recognized through white hair, whiskers, and paws, and loss of pigments in the eyes. The tyrosinase activity and melanin levels in the whisker follicles of TYR(–/–) knockout mice also decreased significantly (P

Ionizing radiation (IR) can induce autophagy and premature senescence; however, the link between them has not been clarified. Our research has shown that X-ray irradiation induces premature senescence in lung adenocarcinoma cells, and its occurrence partially depends on the signal transducer and activator of transcription 3 (STAT3). STAT3 can bind to the promoter region of Beclin1 and regulate its expression. Therefore, it is speculated that there may be a close link between premature senescence and autophagy induced by ionizing radiation in lung adenocarcinoma cells. p62 plays a regulatory role in both autophagy and premature senescence, and it is also an irreplaceable molecule that causes the senescence -associated secretory phenotype (SASP) and a substrate for selective autophagy. This study focused on STAT3, Beclin1 and p62 to clarify the regulatory relationship between IR-induced autophagy and premature senescence.After exposure to 4 Gy X-rays, a β-galactosidase staining kit was used to detect the positive rate of premature senescence. STAT3 was overexpressed by pcDNA3.0-STAT3 transfection, and was inhibited by AG490 and rapamycin. Lung adenocarcinoma cells were transduced with the adenovirus vector GV119-Beclin1 to knockdown the expression of Beclin1, or treated with ATM and ATR inhibitors to inhibit premature senescence. Western blotting was used to examine alterations in the radiation response proteins STAT3 and p-STAT3, senescence-related proteins p62 and GATA4, autophagy-related proteins Beclin1, and LC3-II/LC3-I. The mRNA expression levels of SASP factors, including IL-6 and IL-8, were examined by real-time polymerase chain reaction.The activity of SA-β-gal increased significantly (Radiation induces premature senescence and autophagy in lung adenocarcinoma cells. Autophagy regulates X-ray radiation-induced premature senescence through the STAT3-Beclin1-p62 pathway in lung adenocarcinoma cells.

The intestinal compensatory proliferative potential is a key influencing factor for susceptibility to radiation-induced intestinal injury. Studies indicated that the carnitine palmitoyltransferase 1 (CPT1) mediated fatty acid β-oxidation (FAO) plays a crucial role in promoting the survival and proliferation of tumor cells. Here, we aimed to explore the effect of 60Co gamma rays on CPT1 mediated FAO in the radiation-induced intestinal injury models, and investigate the role of CPT1 mediated FAO in the survival and proliferation of intestinal cells after irradiation. We detected the changed of FAO in the plasma and small intestine of Sprague Dawley (SD) rats at 24 h after 60Co gamma irradiation (0, 5 and 10 Gy), using target metabolomics, qRT-PCR, immunohistochemistry (IHC), western blot (WB) and related enzymatic activity kits. We then analyzed the FAO changes in radiation-induced intestinal injury models regardless of ex vivo (mice enteroids), or in vitro (normal human intestinal epithelial cell lines, HIEC-6). HIEC-6 cells were transduced with lentivirus vector GV392 and treated with puromycin for obtaining CPT1 stable knockout cell lines, named CPT1 KO. CPT1 enzymatic activities of HIEC-6 cells and mice enteroids were also inhibited by pharmaceutical inhibitor ST1326 and Etomoxir (ETO), to study the function of CPT1 in the survival and proliferation of HIEC-6 cells after 60Co gamma irradiation. We found that CPT1 mediated FAO was altered in the small intestine of the SD rats after irradiation, especially, the expression level and enzymatic activity of CPT1 were significantly increased. Similarly, the expression levels of CPT1 were also remarkably enhanced in mice enteroids and HIEC-6 cells after irradiation. CPT1 inhibition decreased the proliferation of the HIEC-6 cells and mice enteroids after irradiation partially by reducing the extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) pathways activation, CPT1 inhibition also reduced the proliferation of mice enteroids after irradiation partially by down-regulating the Wnt/β-catenin signaling activity. In conclusion, our study indicated that CPT1 plays a crucial role in promoting intestinal epithelial cell proliferation after irradiation.

The objective of this research was to explore the dose-effect relationships of dicentric plus ring (dic + r), micronucleus (MN) and nucleoplasmic bridges (NPB) induced by carbon ions in human lymph...

With the development of radiation metabolomics, a large number of radiation-related metabolic biomarkers have been identified and validated. The L-carnitine and acylcarnitines have the potential to be the new promising candidate indicators of radiation exposure. This review summarizes the effect of carnitine shuttle system on the profile of acylcarnitines and correlates the radiation effects on upstream regulators of carnitine shuttle system with the change characteristics of L-carnitine and acylcarnitines after irradiation across different animal models as well as a few humans.Studies report that acylcarnitines were ubiquitously elevated after irradiation, especially the free L-carnitine and short-chain acylcarnitines (C2-C5). However, the molecular mechanism underlying acylcarnitine alterations after irradiation is not fully investigated, and further studies are needed to explore the biological effect and its mechanism. The activity of the carnitine shuttle system plays a key role in the alteration of L-carnitine and acylcarnitines, and the upstream regulators of the system are known to be affected by irradiation. These evidences indicate that that there is a logistic role of carnitine shuttle system on radiation-induced L-carnitine and acylcarnitines alteration.

In the event of radiological accidents and cancer radiotherapies in the clinic, the gastrointestinal (GI) system is vulnerable to ionizing radiation and shows GI injury. Accessible biomarkers may provide means to predict, evaluate, and treat GI tissue damage. The current study investigated radiation GI injury biomarkers in rat plasma. High-coverage targeted lipidomics was employed to profile lipidome perturbations at 72 h after 0, 1, 2, 3, 5, and 8 Gy (60Co γ-rays at 1 Gy/min) total-body irradiation in male rat jejunum. The results were correlated with previous plasma screening outcomes. In total, 93 differential metabolites and 28 linear dose-responsive metabolites were screened in the jejunum. Moreover, 52 lipid species with significant differences both in jejunum and plasma were obtained. Three lipid species with linear dose-response relationship both in jejunum and plasma were put forth, which exhibited good to excellent sensitivity and specificity in triaging different exposure levels. The linear dose-effect relationship of lipid metabolites in the jejunum and the triage performance of radiation GI injury biomarkers in plasma were studied for the first time. The present study can provide insights into expanded biomarkers of IR-mediated GI injury and minimally invasive assays for evaluation.

A variety of secondary metabolites contributing to plant growth are synthesized by bacterial nonribosomal peptide synthases (NRPSs). Among them, the NRPS biosynthesis of surfactin is regulated by the SrfA operon. To explore the molecular mechanism for the diversity of surfactins produced by bacteria within the genus Bacillus, we performed a genome-wide identification study focused on three critical genes of the SrfA operon—SrfAA, SrfAB and SrfAC—from 999 Bacillus genomes (belonging to 47 species). Gene family clustering indicated the three genes can be divided into 66 orthologous groups (gene families), of which a majority comprised members of multiple genes (e.g., OG0000009 had members of all three SrfAA, SrfAB and SrfAC genes), indicating high sequence similarity among the three genes. Phylogenetic analyses also found that none of the three genes formed monophyletic groups, but were usually arranged in a mixed manner, suggesting the close evolutionary relationship among the three genes. Considering the module structure of the three genes, we propose that self-duplication, especially tandem duplications, might have contributed to the initial establishment of the entire SrfA operon, and further gene fusion and recombination as well as accumulated mutations might have continuously shaped the different functional roles of SrfAA, SrfAB and SrfAC. Overall, this study provides novel insight into metabolic gene clusters and operon evolution in bacteria.

Objective This study aims to analyze the alteration of carnitine profile in the small intestine of abdominal irradiation-induced intestinal injury rats and explore the possible reason for the altered carnitine profile. Methods The abdomens of 15 male Sprague Dawley (SD) rats were irradiated with 0, 10, and 15 Gy of 60Co gamma rays. The carnitine profile in the small intestine and plasma samples of SD rats at 72 h after abdominal irradiated with 0 Gy or 10 Gy of 60Co gamma rays were measured by targeted metabolomics. The changes of fatty acid β-oxidation (FAO), including the expression of carnitine palmitoyltransferase 1 (CPT1) and acyl-CoA dehydrogenases, were analyzed in the small intestine samples of SD rats after exposed to 0, 10, and 15 Gy groups. Results There were eleven acylcarnitines in the small intestine and fourteen acylcarnitines in the plasma of the rat model significantly enhanced, respectively (P < .05). The expression level and activity of CPT1 in the small intestine were remarkably increased (P < .05), and the activity of acyl-CoA dehydrogenase in the small intestine was noticeably reduced (P < .01) after abdominal irradiation. Conclusion The enhanced acylcarnitine levels in the small intestine of abdominal irradiation rats might relate to the FAO pathway disequilibration.

Plenty of reports focus on the effects of low-dose radiation (LDR) on peripheral blood lymphocytes in radiation workers. However, studies on red blood cells (RBCs) in radiation workers are rarely reported. Many studies focused on investigate the hemogram of radiation staffs without detecting other components of RBCs. To explore the potential effect of LDR on RBCs, we detected the level of RBC count, hemoglobin, 2,3-disphosphoglycerate (2,3-DPG), and glutathione (GSH), and then analyzed the factors on these indices in 106 medical radiation workers. As a result, RBC count was affected by sex, age, type of work, length of service (only for females), and annual effective dose (only for males). Hemoglobin status was affected by sex, type of work, and annual effective dose (only for males). Sex, age, and type of work had no effects on the concentration of 2,3-DPG and GSH. Length of service affected 2,3-DPG concentration, and annual effective dose affected GSH level. In conclusion, chronic occupational LDR exposure may have an effect on RBC count, hemoglobin status, and the concentration of 2,3-DPG and GSH in radiation workers to some extent. However, it is still unknown how this kind of influence affects the health of radiation workers.

In order to assess the health risk of low-dose radiation to radiation professionals, monitoring is performed through chromosomal aberration analysis and micronuclei (MN) analysis. MN formation has drawbacks for monitoring in the low-dose range. Nucleoplasmic bridge (NPB) analysis, with a lower background level, has good dose-response relationships at both high and relatively low dose ranges. Dicentric and ring chromosomes were analyzed in 199 medical radiation professionals, and NPB/MN yields were analyzed in 205 radiation professionals. The effects of sex, age of donor, types of work, and length of service on these cytogenetic endpoints were also analyzed. The yields of the three cytogenetic endpoints were significantly higher in radiation professionals versus controls. Frequencies of dicentric plus ring chromosomes were affected by length of service. NPB frequencies were influenced by type of work and length of service. MN yields were affected not only by types of work and length of service but also by donor sex and age. In conclusion, dicentric plus ring chromosomes, NPB, and MN can be induced by low-dose radiation in radiation professionals. NPB is a potential biomarker to assess the health risk of occupational low-dose radiation exposure.

The objective of this research was to explore the dose-effect relationships of dicentric plus ring (dic + r), micronucleus (MN) and nucleoplasmic bridges (NPB) induced by carbon ions in human lymphocytes.Venous blood samples were collected from three healthy donors.The frequencies of dic + r, MN and NPB showed significantly increases in a dose-depended manner after exposure toThe dose-response curves of carbon ions-induced dic + r, MN and NPB were constructed. These results could be helpful to improve radiation risk assessment and dose estimation after exposed to carbon ions irradiation.

Rapid early triage and dose estimation is vital for limited medical resource allocation and treatment of a large number of the wounded after radiological accidents. Lipidomics has been utilized to delineate biofluid lipid signatures after irradiation. Here, high-coverage targeted lipidomics was employed to screen radiosensitive lipids after 0, 1, 2, 3, 5, and 8 Gy total body irradiation at 4, 24, and 72 h postirradiation in rat plasma. Ultra-performance liquid chromatography-tandem mass spectrometry with a multiple reaction monitoring method was utilized. In total, 416 individual lipids from 18 major classes were quantified and those biomarkers altered in a dose-dependent manner constituted panel A-panel D. Receiver operator characteristic curve analysis using combined lipids showed good to excellent sensitivity and specificity in triaging different radiation exposure levels (area under curve = 0.814-1.000). The equations for dose estimation were established by stepwise regression analysis for three time points. A novel strategy for radiation early triage and dose estimation was first established and validated using panels of lipids. Our study suggests that it is feasible to acquire quantitative lipid biomarker panels using targeted lipidomics platforms for rapid, high-throughput triage, which can provide further insights in developing lipidomics strategies for radiation biodosimetry in humans.

Previous studies showed that the yield of cobalt-60 γ-rays-induced nucleoplasmic bridges (NPB) in human peripheral blood lymphocytes is dose dependent. However, the influence of the radiation quality and dose rates on NPB frequencies has not been investigated. The present study aimed to investigate NPB frequencies in human peripheral blood lymphocytes induced by carbon ions and explore the dose rate effect on cobalt-60 γ-rays-induced NPB. To establish dose-response curves, human peripheral blood samples were irradiated with 0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 and 8.0 Gy of carbon ions at a dose rate of 3.0 Gy/min in vitro. To explore the dose rate effect, human peripheral blood samples were irradiated with 2.0 and 5.0 Gy of cobalt-60 γ-rays at dose rates of 0.2, 0.5, 1.0, 3.0, 5.0 and 10.0 Gy/min in vitro. NPB and micronuclei (MN) in binucleated cells were analyzed with the cytokinesis-block micronucleus cytome assay. Results showed that the dose-response curve of carbon ion-induced NPB frequencies follow a linear-quadratic model (R2 = 0.934). The relative biological effectiveness (RBE) values of carbon ions to cobalt-60 γ-rays decreased with increased NPB frequencies (ranging from 2.47 to 5.86). Compared with group 1.0 Gy/min, the NPB frequencies in groups 10.0 Gy/min (2.0 Gy), 5.0 and 10.0 Gy/min (5.0 Gy) were decreased significantly (P < 0.05). Carbon ion-induced NPB in human peripheral blood lymphocytes have a good dose-response relationship. Cobalt-60 γ-rays-induced NPB frequencies are affected by the specific dose rate.

Purpose: Simple, rapid and high-throughput dose assessment is critical for clinical diagnosis, treatment and emergency intervention in a large-scale radiological accident. The goal of this study is...

Baseline nucleoplasmic bridges (NPB) vary widely in the general population from different regions in the same country or from different countries. The baseline NPB level in the normal Chinese population and the factors affecting the baseline and radiation-induced NPB levels have not been explored yet. The cytokinesis-block micronucleus cytome assay was conducted on the peripheral blood samples of 121 healthy individuals for the baseline NPB and 52 healthy individuals for the 2 Gy γ-ray-induced NPB level. The effects of age and gender on the baseline NPB and 2 Gy γ-ray-induced NPB level were evaluated. The overall baseline NPB in the peripheral blood lymphocytes of 121 healthy adults from the general population in China was 0.46 ± 0.20 per 1000 binucleated (BN) cells. The overall baseline NPB in males (0.56 ± 0.15 per 1000 BN cells) was higher than that in females (0.36 ± 0.22 per 1000 BN cells, P

Chromosome damage is related to DNA damage and erroneous repair. It can cause cell dysfunction and ultimately induce carcinogenesis. Histone acetylation is crucial for regulating chromatin structure and DNA damage repair. Ionizing radiation (IR) can alter histone acetylation. However, variations in histone acetylation in response to IR exposure and the relationship between histone acetylation and IR-induced chromosome damage remains unclear. Hence, this study investigated the variation in the total acetylation levels of H3 and H4 in human lymphocytes exposed to 0-2 Gy 60Co γ-rays. Suberoylanilide hydroxamic acid (SAHA), a histone deacetylase (HDAC) inhibitor, was added to modify the histone acetylation state of irradiated cells. Then, the total acetylation level, enzyme activity, dicentric plus centric rings (dic + r) frequencies, and micronucleus (MN) frequencies of the treated cells were analyzed. Results indicated that the acetylation levels of H3 and H4 significantly decreased at 1 and 24 h, respectively, after radiation exposure. The acetylation levels of H3 and H4 in irradiated groups treated with SAHA were significantly higher than those in irradiated groups that were not treated with SAHA. SAHA treatment inhibited HDAC activity in cells exposed to 0-1 Gy 60Co γ-rays. SAHA treatment significantly decreased dic + r/cell and MN/cell in cells exposed to 0.5 or 1.0 Gy 60Co γ-rays relative to that in cells that did not receive SAHA treatment. In conclusion, histone acetylation is significantly affected by IR and is involved in chromosome damage induced by 60Co γ-radiation.

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.

In a large-scale radiological incident, rapid and high-throughput biodosimetry would be needed. Gene expression-based biodosimetry is a promising approach to determine the dose received after radiation exposure. We previously identified 35 candidate genes as biodosimetry markers based on a systematic review. The goal of the current study was to establish and validate a specific gene expression-based radiological biodosimetry using a panel of highly radioresponsive genes in human peripheral blood for improving the accuracy of dose estimation. Human peripheral blood samples from 30 adult donors were irradiated to 0, 0.5, 1, 2, 3, 4, 6 and 8 Gy with 60Co γ rays at a dose rate of 1 Gy/min. We examined the expression patterns of candidate genes using real-time polymerase chain reaction (qRT-PCR) at 6, 12, 24 and 48 h postirradiation. Stepwise regression analysis was employed to develop the gene expression-based dosimetry models at each time point. Samples from another 10 healthy donors (blind samples) and four total-body irradiated (TBI) patients were used to validate the radiation dosimetry models. We observed significant linear dose-response relationships of CDKN1A, BAX, MDM2, XPC, PCNA, FDXR, GDF-15, DDB2, TNFRSF10B, PHPT1, ASTN2, RPS27L, BBC3, TNFSF4, POLH, CCNG1, PPM1D and GADD45A in human peripheral blood at the various time points. However, the expression levels of these genes were affected by inter-individual variations and gender. We found that the gender-dependent regression models could explain 0.85 of variance at 24 h postirradiation and could also accurately estimate the absorbed radiation doses with dose range of 0-5 Gy, in human peripheral blood samples irradiated ex vivo and from TBI patients, respectively. This study demonstrates that developing gender-specific biodosimetry based on a panel of highly radioresponsive genes may help advance the application of gene expression signature for dose estimation in the event of a radiological accident or in clinical treatment.

Baseline nucleoplasmic bridges (NPB) vary widely in the general population from different regions in the same country or from different countries. The baseline NPB level in the normal Chinese population and the factors affecting the baseline and radiation-induced NPB levels have not been explored yet. The cytokinesis-block micronucleus cytome assay was conducted on the peripheral blood samples of 121 healthy individuals for the baseline NPB and 52 healthy individuals for the 2 Gy γ-ray-induced NPB level. The effects of age and gender on the baseline NPB and 2 Gy γ-ray-induced NPB level were evaluated. The overall baseline NPB in the peripheral blood lymphocytes of 121 healthy adults from the general population in China was 0.46 ± 0.20 per 1000 binucleated (BN) cells. The overall baseline NPB in males (0.56 ± 0.15 per 1000 BN cells) was higher than that in females (0.36 ± 0.22 per 1000 BN cells, P 0.05). The effect of age on the baseline NPB was not significant, except for females in the 40-year age group. The overall 2 Gy γ-ray-induced NPB frequency for male donors was lower than that for female donors (P 0.01). No evident trend of the radiation-induced NPB level with increasing age was observed for both genders. For the baseline micronucleus (MN) and radiation-induced MN levels, the effects of gender and age were confirmed. Therefore, the gender of donors affects the baseline and radiation-induced levels of NPB and MN. In addition, the effect of the age of the donors on the baseline and radiation-induced NPB levels showed no clear pattern and needed to be further investigated.

A cobalt-60 irradiation accident occurred in Shanxi, China, on April 11, 2008. Five people were exposed to total-body irradiation ranging from 1.7 to 14.5 Gy. Two victims died post-irradiation, due to acute intestinal radiation sickness (at 62 days) and tuberculosis (at 1.5 year). The other three victims received medical follow-ups and were monitored for 5 years with multiple cytogenetic analyses. Unstable chromosome aberrations, including dicentric and centric rings (dic+r) and the micronucleus frequency in binucleated lymphocytes, were monitored. In addition, G-banding karyotype and fluorescence in situ hybridization (FISH) methods were used to analyze translocations, for exploring chromosome stability and for retrospective dosimetry. The results show that unstable chromosome aberrations (dic+r) declined each year, dropping to about 20-40% of initial levels by the 5th year. A similar trend was observed for the micronucleus frequency. Our results show that the translocation frequencies of the three victims, detected by G-banding karyotype, remained stable for the 5 years. Five years after irradiation, the translocation rates of the three victims (G-banding and FISH analyses) were similar. The retrospective estimated doses, reconstructed based on the translocation frequencies, were consistent with the biological doses estimated at the first day post-irradiation using dic+r. The results of this study indicate that chromosome translocation frequencies can be used as a biological dosimeter and are an excellent index for dose reconstruction.

The aim of the present study is to analyze the global research trend of radiation-responsive genes and identify the highly reproducible radiation-responsive genes. Bibliometric methods were applied to analyze the global research trend of radiation-responsive genes. We found 79 publications on radiation-responsive genes from 2000 to 2017. A total of 35 highly reproducible radiation-responsive genes were identified. Most genes are involved in response to DNA damage, cell proliferation, cell cycle regulation, and DNA repair. The p53 signal pathway was the top enriched pathway. The expression levels of 18 genes in human B lymphoblastoid cell line (AHH-1) cells were significantly up-regulated in a dose-dependent manner at 24 h after exposure to 0-5 Gy 60Co γ-ray irradiation. Our results indicate that developing a gene expression panel with the 35 high reproducibility radiation-responsive genes may be necessary for qualitative and quantitative assessment after exposure.

A quantitative survey of rice planthoppers in paddy fields is important to assess the population density and make forecasting decisions. Manual rice planthopper survey methods in paddy fields are time-consuming, fatiguing and tedious. This paper describes a handheld device for easily capturing planthopper images on rice stems and an automatic method for counting rice planthoppers based on image processing. The handheld device consists of a digital camera with WiFi, a smartphone and an extrendable pole. The surveyor can use the smartphone to control the camera, which is fixed on the front of the pole by WiFi, and to photograph planthoppers on rice stems. For the counting of planthoppers on rice stems, we adopt three layers of detection that involve the following: (a) the first layer of detection is an AdaBoost classifier based on Haar features; (b) the second layer of detection is a support vector machine (SVM) classifier based on histogram of oriented gradient (HOG) features; (c) the third layer of detection is the threshold judgment of the three features. We use this method to detect and count whiteback planthoppers ( Sogatella furcifera ) on rice plant images and achieve an 85.2% detection rate and a 9.6% false detection rate. The method is easy, rapid and accurate for the assessment of the population density of rice planthoppers in paddy fields.

To identify new ionizing radiation (IR)-sensitive genes and observe the dose-effect of gene expression alteration (GEA) induced by IR.Microarray was used to screen the differentially expressed genes in human lymphoblastoid cells (AHH-1) using three doses of (60)Co γ-rays (0.5-8 Gy at 1 Gy/min). Given that p53-inducible gene 3 (PIG3) was consistently upregulated, the GEA of PIG3 in AHH-1 cells and human peripheral blood lymphocytes (HPBL) induced by γ-rays (1 Gy/min) was measured at messenger RNA (mRNA) and protein levels. The GEA of PIG3 in AHH-1 cells exposed to neutron radiation (californium-252, 0.073 Gy/min) was also quantified.PIG3 was one of the seven differentially expressed genes found in the microarray analysis. The PIG3 mRNA and protein levels in AHH-1 cells were significantly increased from 1-10 Gy of γ-rays 8-72 h or 8-168 h after exposure, respectively. The enhancement was also observed in AHH-1 cells from 0.4-1.6 Gy of neutrons 48 h post-irradiation. The PIG3 mRNA levels (mRNA copy numbers) in HPBL were significantly increased from 1-8 Gy of γ-rays within 4-24 h post-irradiation, but the highest increase in signal-to-noise responsiveness is approximately two-fold, which was less than that of AHH-1 (approximately 20-fold).IR can upregulate the PIG3 gene expression in AHH-1 and HPBL in the early phase after exposure; however, the IR induced expression levels of PIG3 are greater in AHH-1 than HPBL.

The present study aims to evaluate the use of the fluorescence in situ hybridization (FISH) translocation assay for retrospective dose estimation of acute accidental exposure to radiation in the past. Reciprocal translocation analysis by FISH with three whole-chromosome probes was performed on normal peripheral blood samples. Samples were irradiated with 0–5 Gy 60Co γ-rays in vitro, and dose–effect curves were established. FISH-based translocation analyses for six accident victims were then performed, and biological doses were estimated retrospectively by comparison with the dose–effect curves. Reconstructed doses by FISH were compared with estimated doses obtained by analysis of di-centrics performed soon after exposure, or with dose estimates from tooth-enamel electron paramagnetic resonance (EPR) data obtained at the same time as the FISH analysis. Follow-up FISH analyses for an adolescent victim were performed. Results showed that dose–effect curves established in the present study follow a linear-quadratic model, regardless of the background translocation frequency. Estimated doses according to two dose–effect curves for all six victims were similar. FISH dose estimations of three adult victims exposed to accidental radiation less than a decade prior to analysis (3, 6, or 7 years ago) were consistent with those estimated with tooth-enamel EPR measurements or analyses of di-centrics. Estimated doses of two other adult victims exposed to radiation over a decade prior to analysis (16 or 33 years ago) were underestimated and two to three times lower than the values obtained from analysis of di-centrics or tooth-enamel EPR. Follow-up analyses of the adolescent victim showed that doses estimated by FISH analysis decrease rapidly over time. Therefore, the accuracy of dose estimates by FISH is acceptable only when analysis is performed less than 7 years after exposure. Measurements carried out more than a decade after exposure through FISH analysis resulted in underestimation of the biological doses compared with values obtained through analysis of di-centrics and tooth-enamel EPR.

Earthquake prediction is one of the most difficult problems in modern natural science. Undoubtedly, various seismic parameters included in broadband radiated energy catalogue of NEIC is very important data source of investigate correlation between differernt earthquake within specific time space scope and earthquake prediction. In the paper, we a linear fitting mode of seismic magnitude based on method of least squares and seismic energy is established, using which we can fill the absent energy filed in the broadband radiated energy catalogue.

Earthquake prediction is a difficult global scientific problem. As one aspect of the earthquake prediction, seismicity prediction and subsequent earthquake is also a big difficult of science problems. Analysis of the seismic sequence and the study of the main parameters (magnitude, radiation energy, apparent stress, seismic moment) and subsequent aftershocks is an important basis for prediction of seismicity and subsequent strong earthquakes. In this study, the relations between some of main shock parameters and the maximum aftershock are obtained based on association rules.

In order to extract characteristic values of graphene, a method based on a series of digital image processing algorithms was proposed in this paper. Using the method, we can automatically analyze topology structure and calculate amount of carbon atoms, and even calculate chiral vector indices (n, m) during in-situ TEM scanning of graphene. At last, we also write the correlative software with c++, which applying the digital image processing algorithms, and give out the processing result of several classic TEM image of graphene.

Counting the number of rice pests captured via light traps each day is very important for monitoring the population dynamics of rice pests in paddy fields. This paper focuses on developing a segmentation method for separating the touching insects in the rice light-trap insect image from our imaging system to automatically identify and count rice pests by photographing them on a glass table. When placed on the glass, many specimens may be touching, which interferes with automated identification. To segment touching insects, this paper describes a method in which the glass table is lightly tapped between successive images, which causes the specimens to move slightly. Optical flow is computed between the two images captured before and after insect motion. Normalized cuts (NCuts), with the optical flow angle as the weight function, was applied to separate the touching insects according to the number of insects in each connected region. We compare our method with the k -means and watershed methods. Our method achieves an average rate of good segmentations of 86.9%. In our future work, we will focus on the identification and counting of rice light-trap pests.

The separation efficiency, separation factor, flow and other parameters are closely related in terms of horizontal spiral sedimentation centrifuge. This article takes lwb350 horizontal spiral sedimentation centrifuge for example, with the help of FLUENT software, the relationship among the separation efficiency and the working speed as well as feed flow is analyzed through the numerical simulation of solid-liquid separation, which can provide reference for the application of simulation analysis and research on properties of spiral centrifuge.

Combined with the reconstruction of the existing railway line with speed of 200km/h, a calculation model of bridge-subgrade transition section was developed by the theory of vehicle-track-bridge/subgrade coupling dynamics. The simulation program was compiled, which could be used to calculate and evaluate the dynamic characteristics of transition section in speed-up line. The results of field reconnaissance operations and calculations show that the track structure stiffness in transition section is uneven, or even part of the function fails, which can not meet the requirements of speed-raising. Some measures, such as transition section database establishment, class-based management implementation, separate design and separate reinforcement adoption, can be used for the transition sections, which are listed as the objects of emphatic assessment. In addition, the evaluation system will provide theoretical support and references for design and construction in reconstruction project of transition section.

The dose effect between nucleoplasmic bridges (NPB) and relatively low doses of ionising radiation remains unknown. Accordingly, this study investigated the NPB frequencies in human peripheral blood lymphocytes exposed to low-dose (60)Co γ-rays. Complex anomalies, including fused nuclei (FUS), horse-shoe nuclei (HS) and circular nuclei (CIR), which possibly originated from multiple NPBs, were also scored. Human peripheral blood samples were collected from three healthy males and irradiated with 0-1 and 0-0.4 Gy (60)Co γ-rays. A cytokinesis-block micronucleus cytome assay was then conducted to analyse NPB, PFHC (NPB plus three complex nuclear anomalies) and micronucleus (MN) in binucleated cells. All dose-response curves followed the linear model for both NPB frequency and PFHC cell frequency. The dose-response curves between NPB frequency and absorbed dose at 0-1 and 0-0.4 Gy were y = 0.0037x + 0.0005 (R (2) = 0.979, P < 0.05) and y = 0.0043x + 0.0004 (R (2) = 0.941, P < 0.05), respectively. The dose-response curves between PFHC cell frequency and absorbed dose at 0-1 and 0-0.4 Gy were y = 0.0044x + 0.0007 (R (2) = 0.982, P < 0.05) and y = 0.0059x + 0.0005 (R (2) = 0.969, P < 0.05), respectively. The statistical significance of differences between the irradiated groups (0-0.4 Gy) and background levels of NPB, PFHC and MN were also analysed. The lowest analysable doses of NPB, PFHC and MN were 0.12, 0.08 and 0.08 Gy, respectively. In conclusion, NPBs and PFHC positively correlated with the absorbed radiation at a relatively low dose.

Many studies have investigated exposure biomarkers for high dose radiation. However, no systematic study on which biomarkers can be used in dose estimation through premature chromosome condensation (PCC) analysis has been conducted. The present study aims to screen the high-dose radiation exposure indicator in calyculin A-induced PCC. The dose response of multiple biological endpoints, including G2/A-PCC (G2/M and M/A-PCC) index, PCC ring (PCC-R), ratio of the longest/shortest length (L/L ratio), and length and width ratio of the longest chromosome (L/B ratio), were investigated in calyculin A-induced G2/A-PCC spreads in human peripheral blood lymphocytes exposed to 0–20 Gy (dose–rate of 1 Gy/min) cobalt-60 gamma-rays. The G2/A-PCC index was decreased with enhanced absorbed doses of 4–20 Gy gamma-rays. The G2/A PCC-R at 0–12 Gy gamma-rays conformed to Poisson distribution. Three types of PCC-R were scored according to their shape and their solidity or hollowness. The frequencies of hollow PCC-R and PCC-R including or excluding solid ring in G2/A-PCC spreads were enhanced with increased doses. The length and width of the longest chromosome, as well as the length of the shortest chromosome in each G2/M-PCC or M/A-PCC spread, were measured. All L/L or L/B ratios in G2/M-PCC or M/A-PCC spread increased with enhanced doses. A blind test with two new irradiated doses was conducted to validate which biomarker could be used in dose estimation. Results showed that hollow PCC-R and PCC-R including solid ring can be utilized for accurate dose estimation, and that hollow PCC-R was optimal for practical application.

As the rapid development of China’s national economy, China’s construction industry shows a rapid growth. Because construct project has the feature of large investment and long construction time, there are many unforeseen factors in the construction process. The project participants may face many risks. This paper firstly analyses risk factors of construction project, secondly describes the mathematical models—SVM, and then on the basis of the method builds the model of construction project risk prediction. Lastly it uses example to prove the feasibility of the model, and it also provides an effective method for the construction project risk management.

To investigate the late effects of radiation on child-bearing women, a follow-up study was performed on a 39-year-old survivor 16 years after a (60)Co radiation accident. The woman, Fang, was 19 weeks pregnant at the time of exposure. Physical examinations, a full range of clinical laboratory and imaging tests, as well as cytogenetic analyses were conducted to evaluate Fang's current health conditions. Fang shows the appearance of premature ageing and has a decreased menstrual period. Laboratory studies and imaging tests suggest nodular goitre disease and osteoporosis. Otherwise, no apparent abnormalities were found in the major organs. No malignant tumours were detected by either tumour markers or imaging tests. However, the existence of chromosome aberrations warrants long-term follow-up for tumour incidence in the future. Fang became pregnant 8 years after the accident, but suffered a miscarriage due to the death of the foetus at 6 months into the pregnancy. In conclusion, our findings suggest that the intrauterine death of the foetus might be associated with the previous exposure. There is no evidence of malignant tumours as of the date of the follow-up study. Non-cancerous diseases, i.e. thyroid disease and osteoporosis, which may be related to radiation exposure, are the major manifestations of the long-term effects of the accident.

Gyroscope is the core of an inertia system and made by machining process. Machining process imports large residual stress. The residual stress will be released and induces large deformation of gyroscope frame. In this paper, the effects of residual stress on deformation of gyroscope frame were simulated by finite element method. Different stress distribution leads different deformation. Compressive stress can make sample long and tensile stress make sample short. The stress released in deformation process which reduced about 90%.

Phyllodes tumors are not quite rare fibroepithelial neoplasms of the breast that show a broad spectrum of clinical behaviour. The molecular genetic features of the heterogenous groups of neoplasms have not been studied in detail yet. We have used comparative genomic hybridization to analyze chromosomal copy number changes in 36 cases of phyllodes tumors (including benign, borderline and malignant phyllodes tumors, 12 cases each). The average number of chromosome copy changes (range) in benign, borderline and malignant phyllodes tumors were 5.58 (0-20), 14.08 (3-23), and 12.42 (0-29) respectively. In benign phyllodes tumors the number of gains and losses was in balance (2.50 vs 3.08), while in borderline and malignant phyllodes tumors gains occurred more often than losses (9.25 vs 4.83, 9.5 vs 2.92). The result suggests the molecular cytogenetics of borderline and malignant phyllodes tumors is similar, and the most striking difference with benign phyllodes tumors is an increased number of chromosomal gains in a nonrandom distribution. Gains of 4q12 seem especially to be involved in the progression of benign to borderline and malignant phyllodes tumors, possibly because of overexpression of oncogenes at these loci.

The research on structural vibration and sound radiation of underwater ring-ribbed cylindrical shell, which is coated with a kind of deadening and decoupling materials, becomes a focus in recent years. This paper analyzes the problem on two aspects: model experiment and numerical calculation. The model experiment is carried out including three cases firstly, in which the structural vibration response and radiating acoustic field are measured respectively, and the results gained in these three cases are analyzed to discuss the effect of reducing structural vibration and radiating noise of the deadening and decoupling materials. The coupling FEM/BEM and the SEA methods are both used in numerical calculation, i.e. the arithmetic of the coupling FEM/BEM method is adopted to calculate the low frequency characteristics and the SEA method is adopted to calculate the medium-high frequencies characteristics of the model. By comparing experimental results with numerical calculation results, it is proved that the algorithm adopted in this paper is reasonable.

Rapid identification of minerals based on near infrared (NIR) and shortwave infrared (SWIR) hyperspectra is vital to remote sensing mine exploration, remote sensing minerals mapping and field geological documentation of drill core, and have leaded to many identification methods including spectral angle mapping (SAM), spectral distance mapping (SDM), spectral feature fitting(SFF), linear spectral mixture model (LSMM), mathematical combination feature spectral linear inversion model(CFSLIM) etc. However, limitations of these methods affect their actual applications. The present paper firstly gives a unified minerals components spectral inversion (MCSI) model based on target sample spectrum and standard endmember spectral library evaluated by spectral similarity indexes. Then taking LSMM and SAM evaluation index for example, a specific formulation of unified MCSI model is presented in the form of a kind of combinatorial optimization. And then, an artificial immune colonial selection algorithm is used for solving minerals feature spectral linear inversion model optimization problem, which is named ICSFSLIM. Finally, an experiment was performed to use ICSFSLIM and CFSLIM to identify the contained minerals of 22 rock samples selected in Baogutu in Xinjiang China. The mean value of correctness and validness identification of ICSFSLIM are 34.22% and 54.08% respectively, which is better than that of CFSLIM 31.97% and 37.38%; the correctness and validness variance of ICSFSLIM are 0.11 and 0.13 smaller than that of CFSLIM, 0.15 and 0.25, indicating better identification stability.

Model selection for support vector machine (SVM) involving kernel and the margin parameter values selection is usually time-consuming, impacts training efficiency of SVM model and final classification accuracies of SVM hyperspectral remote sensing image classifier greatly. Firstly, based on combinatorial optimization theory and cross-validation method, artificial immune clonal selection algorithm is introduced to the optimal selection of SVM (CSSVM) kernel parameter a and margin parameter C to improve the training efficiency of SVM model. Then an experiment of classifying AVIRIS in India Pine site of USA was performed for testing the novel CSSVM, as well as a traditional SVM classifier with general Grid Searching cross-validation method (GSSVM) for comparison. And then, evaluation indexes including SVM model training time, classification overall accuracy (OA) and Kappa index of both CSSVM and GSSVM were all analyzed quantitatively. It is demonstrated that OA of CSSVM on test samples and whole image are 85.1% and 81.58, the differences from that of GSSVM are both within 0.08% respectively; And Kappa indexes reach 0.8213 and 0.7728, the differences from that of GSSVM are both within 0.001; While the ratio of model training time of CSSVM and GSSVM is between 1/6 and 1/10. Therefore, CSSVM is fast and accurate algorithm for hyperspectral image classification and is superior to GSSVM.

In November 1992, a radiation accident occurred in Xinzhou, due to the collection by a farmer of an unused (60)Co source; 37 individuals were exposed to ionizing radiation. Three individuals died and the farmer's 19-weeks-pregnant wife suffered acute radiation symptoms. Conventional chromosome analysis, cytokinesis-block micronuclei (CBMN) assay and fluorescence in situ hybridization (FISH) painting with three pairs of whole chromosome probes were used to analyze chromosomal aberrations for the pregnant female and her baby during the 16 years following the accident. The yields of dicentrics and rings (dic+r) continually declined between 41 days and 16 years after the accident. The frequency of binucleated MN also decreased over time for both mother and daughter. Sixteen years after exposure, the yields of dic+r and binucleated MN decreased to normal levels, but the reciprocal translocation frequencies remained elevated, for both mother and daughter. FISH results showed a decreasing yield of translocations with time. Based on the changes in maternal translocation frequency, the daughter's dose at the time of exposure was estimated as 1.82 (1.35-2.54)Gy. This was consistent with the clinical manifestations of severe mental retardation and low IQ score. FISH-based translocation analysis can be used for follow-up studies on accidental exposure and, after correction, for retrospective dose estimation for individuals prenatally exposed to radiation.

We identify ionizing radiation-induced mitochondrial DNA (mtDNA) deletions in human lymphocytes and their distribution in normal populations.Long-range polymerase chain reactions (PCR) using two pairs of primers specific for the human mitochondrial genome were used to analyze the lymphoblastoid cell line following exposure to 10 Gy (60)Co γ-rays. Limited-condition PCR, cloning and sequencing techniques were applied to verify the mtDNA deletions detected with long-range PCR. Human peripheral blood samples were irradiated with 0, 2 and 6 Gy (60)Co γ-rays, and real-time PCR analysis was performed to validate the mtDNA deletions. In order to know the distribution of mtDNA deletions in normal population, 222 healthy Chinese adults were also investigated.Two mtDNA deletions, a 7455-bp deletion (nt475-nt7929 in heavy strand) and a 9225-bp deletion (nt7714 -nt369 in heavy strand), occurring between two 8-bp direct repeats, were identified in lymphoblastoid cells using long-range PCR, limited-condition PCR and sequencing. These results were also observed for (60)Co γ-rays irradiated human peripheral blood cells.Two novel mtDNA deletions, a 7455-bp deletion and a 9225-bp deletion, were induced by ionizing radiation. The rate of the mtDNA deletions within a normal population was related to the donors' age, but was independent of gender.

A follow-up study of the late effects of intrauterine exposure to irradiation has been made on a 16-year-old girl whose mother was exposed to external (60)Co irradiation during the Xinzhou radiation accident 16 years previously. The outcomes of the general medical examinations, conventional chromosome aberration analyses and fluorescence in situ hybridisation (FISH) are presented and the China-revised Wechsler Intelligence Scale for Children (C_WISC) was used to identify her IQ level, which was well below normal for her age. The biological dose of the radiation to which she was exposed when she was in her mother's uterus was inferred to be 1.85 Gy. Although there is no evidence of any other developmental changes or tumour induction at this stage in her life, the child's total intelligence level does appear to have been affected.

Hyperspectral characteristics analysis of ground features is the basis for applications of high-resolution imaging technology to ground target identification and ground features classification. Based on morphological multi-scale Top-Hat transformation, a novel spectral absorption enhancing algorithms was put forward, which enhanced spectral absorption features while maintaining shape features of the absorption peak bands. Eleven reflectance spectra of different mineral groups were chosen from the mineral spectral library of the United States Geological Survey (USGS), and we used a K-means clustering analysis on both the absorption-enhanced spectra and the original reflectance spectra. Results showed that, firstly, clustering groups of the absorption-enhanced spectra (AES) had better similarity within the same clustering group, and greater difference between different groups, furthermore, they were more consistent with the geological background of these minerals compared with clustering result of the original spectra (OS). Secondly, while all the original spectra were re-sampled to their ASTER spectra and the AES clustering result was displayed in the form of ASTER spectra of the minerals, we could easily describe both the representative spectral feature of each clustering group, and the typical spectral differences between every two groups. These fully demonstrate that the absorption-enhanced spectra have enhanced absorption features of the mineral spectra, and improved the separability of hyper-spectra. Accordingly, feature analysis based on absorption enhanced spectra can be used as reference for information extracting based on multi-spectral remote sensing image data, and it is a very useful method of hyperspectral analysis.

Rapid identification of minerals is the key point for enhancing the efficiency of mineral exploration by remote sensing, mineral mapping by remote sensing and many geological investigations. Because of the limitation of technology and other aspects, the amount of models and software concerning rapid identification of minerals is very small. Since 1990s the development in spectrometers and computers has made it possible to apply near infrared spectrum technology to identify minerals. Two models have emerged. Model I is based on analyzing the position of absorption bands, while Model II is founded on waveform matching. In the present paper, characteristic spectrum linear inversion modeling was built. Validated by the data gained from end-members of USGS mineral spectrum library by mixing randomly, this model with the accuracy being approximately 100% is much better than Model I and II. Used to analyze the 23 samples selected in Baogutu area in Xinjiang, the model we built with the accuracy of 64.6% is superior to Model I (the accuracy is 33.8%) and Model II (the accuracy is 8.1%). Though the accuracy of our model is not as high as that of identification by microscope at present, using our model is much more effective and convenient, and there also will be less artificial error and smaller workload. The good performance of our model in the mineral exploration work by remote sensing in Baogutu area in Xinjiang shows wide popularizing prospects.

To recognize ground objects with infrared spectrum, high frequency noise removing is one of the most important phases in spectrum feature analysis and extraction. A new method for infrared spectrum preprocessing was given combining spectrum continuum processing and Fast Fourier Transform (CFFT). Continuum was firstly removed from the noise polluted infrared spectrum to standardize hyper-spectra. Then the spectrum was transformed into frequency domain (FD) with fast Fourier transform (FFT), separating noise information from target information After noise eliminating from useful information with a low-pass filter, the filtered FD spectrum was transformed into time domain (TD) with fast Fourier inverse transform. Finally the continuum was recovered to the spectrum, and the filtered infrared spectrum was achieved. Experiment was performed for chlorite spectrum in USGS polluted with two kinds of simulated white noise to validate the filtering ability of CFFT by contrast with cubic function of five point (CFFP) in time domain and traditional FFT in frequency domain. A circle of CFFP has limited filtering effect, so it should work much with more circles and consume more time to achieve better filtering result. As for conventional FFT, Gibbs phenomenon has great effect on preprocessing result at edge bands because of special character of rock or mineral spectra, while works well at middle bands. Mean squared error of CFFT is 0. 000 012 336 with cut-off frequency of 150, while that of FFT and CFFP is 0. 000 061 074 with cut-off frequency of 150 and 0.000 022 963 with 150 working circles respectively. Besides the filtering result of CFFT can be improved by adjusting the filter cut-off frequency, and has little effect on working time. The CFFT method overcomes the Gibbs problem of FFT in spectrum filtering, and can be more convenient, dependable, and effective than traditional TD filter methods.