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1.
Phytomedicine ; 125: 155290, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308918

RESUMO

BACKGROUND: In our previous study, we provided evidence that Astragalus mongholicus Bunge(AM) and its extracts possess a protective capability against radiation-induced damage, potentially mediated through the reduction of reactive oxygen species (ROS) and nitric oxide (NO). However, we were pleasantly surprised to discover during our experimentation that AM not only offers protection against radiation damage but also exhibits a radiation sensitization effect. This effect may be attributed to a specific small molecule present in AM known as ononin. Currently, radiation sensitizers are predominantly found in nitrazole drugs and nanomaterials, with no existing reports on the radiation sensitization properties of ononin, nor its underlying mechanism. PURPOSE: This study aims to investigate the sensitization effect of the small molecule ononin derived from AM on lung cancer radiotherapy, elucidating its specific molecular mechanism of action. Additionally, the safety profile of combining astragalus small molecule ononin with radiation therapy will be evaluated. METHODS: The effective concentration of ononin was determined through cell survival experiments, and the impact of ononin combined with varying doses of radiation on lung cancer cells was observed using CCK-8 and cell cloning experiments. The apoptotic effect of ononin combined with radiation on lung cancer cells was assessed using Hochester staining, flow cytometry, and WB assay. Additionally, WB and immunofluorescence analysis were conducted to investigate the influence of ononin on HIF-1α/VEGF pathway. Furthermore, Molecular Dynamics Simulation was employed to validate the targeted binding ability of ononin and HIF-1α. A lung cancer cell line was established to investigate the effects of knockdown and overexpression of HIF-1α. Subsequently, the experiment was repeated using tumor bearing nude mice and C57BL/6 mouse models in an in vivo study. Tumor volume was measured using a vernier caliper, while HE, immunohistochemistry, and immunofluorescence techniques were employed to observe the effects of ononin combined with radiation on tumor morphology, proliferation, and apoptosis. Additionally, Immunofluorescence was employed to examine the impact of ononin on HIF-1α/VEGF pathway in vivo, and its effect on liver function in mice was assessed through biochemistry analysis. RESULTS: At a concentration of 25 µM, ononin did not affect the proliferation of lung epithelial cells but inhibited the survival of lung cancer cells. In vitro experiments demonstrated that the combination of ononin and radiation could effectively inhibit the growth of lung cancer cells, induce apoptosis, and suppress the excessive activation of the Hypoxia inducible factor 1 alpha/Vascular endothelial growth factor pathway. In vivo experiments showed that the combination of ononin and radiation reduced the size and proliferation of lung cancer tumors, promoted cancer cell apoptosis, mitigated abnormal activation of the Hypoxia inducible factor 1 alpha pathway, and protected against liver function damage. CONCLUSION: This study provides evidence that the combination of AM and its small molecule ononin can enhance the sensitivity of lung cancer to radiation. Additionally, it has been observed that this combination can specifically target HIF-1α and exert its effects. Notably, ononin exhibits the unique ability to protect liver function from damage while simultaneously enhancing the tumor-killing effects of radiation, thereby demonstrating a synergistic and detoxifying role in tumor radiotherapy. These findings contribute to the establishment of a solid basis for the development of novel radiation sensitizers derived from traditional Chinese medicine.


Assuntos
Glucosídeos , Isoflavonas , Neoplasias Pulmonares , Radiossensibilizantes , Camundongos , Animais , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Camundongos Nus , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Fatores de Crescimento do Endotélio Vascular/metabolismo , Tolerância a Radiação , Radiossensibilizantes/farmacologia , Fator 1 Induzível por Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia
2.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958568

RESUMO

Copper and zinc organometallics have multiple applications and many are considered "data-poor" because the available toxicological information is insufficient for comprehensive health risk assessments. To gain insight into the chemical prioritization and potential structure activity relationship, the current work compares the in vitro toxicity of nine "data-poor" chemicals to five structurally related chemicals and to positive DNA damage inducers (4-nitroquinoline-oxide, aflatoxin-B1). The HC-04 non-cancer human liver cell line was used to investigate the concentration-response effects (24 h and 72 h exposure) on cell proliferation, DNA damage (γH2AX and DNA unwinding assays), and epigenetic effects (global genome changes in DNA methylation and histone modifications using flow cytometry). The 24 h exposure screening data (DNA abundance and damage) suggest a toxicity hierarchy, starting with copper dimethyldithiocarbamate (CDMDC, CAS#137-29-1) > zinc diethyldithiocarbamate (ZDEDC, CAS#14324-55-1) > benzenediazonium, 4-chloro-2-nitro-, and tetrachlorozincate(2-) (2:1) (BDCN4CZ, CAS#14263-89-9); the other chemicals were less toxic and had alternate ranking positions depending on assays. The potency of CDMDC for inducing DNA damage was close to that of the human hepatocarcinogen aflatoxin-B1. Further investigation using sodium-DMDC (SDMDC, CAS#128-04-1), CDMDC and copper demonstrated the role of the interactions between copper and the DMDC organic moiety in generating a high level of CDMDC toxicity. In contrast, additive interactions were not observed with respect to the DNA methylation flow cytometry data in 72 h exposure experiments. They revealed chemical-specific effects, with hypo and hypermethylation induced by copper chloride (CuCl2, CAS#10125-13-0) and zinc-DMDC (ZDMDC, CAS#137-30-4), respectively, but did not show any significant effect of CDMDC or SDMDC. Histone-3 hypoacetylation was a sensitive flow cytometry marker of 24 h exposure to CDMDC. This study can provide insights regarding the prioritization of chemicals for future study, with the aim being to mitigate chemical hazards.


Assuntos
Cobre , Zinco , Humanos , Cobre/metabolismo , Zinco/metabolismo , Fígado/metabolismo , Dano ao DNA , Linhagem Celular , Aflatoxina B1/toxicidade , Epigênese Genética , DNA/metabolismo
3.
Arch Toxicol ; 97(8): 2245-2259, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37341741

RESUMO

Mutagenicity testing is an essential component of health safety assessment. Duplex Sequencing (DS), an emerging high-accuracy DNA sequencing technology, may provide substantial advantages over conventional mutagenicity assays. DS could be used to eliminate reliance on standalone reporter assays and provide mechanistic information alongside mutation frequency (MF) data. However, the performance of DS must be thoroughly assessed before it can be routinely implemented for standard testing. We used DS to study spontaneous and procarbazine (PRC)-induced mutations in the bone marrow (BM) of MutaMouse males across a panel of 20 diverse genomic targets. Mice were exposed to 0, 6.25, 12.5, or 25 mg/kg-bw/day for 28 days by oral gavage and BM sampled 42 days post-exposure. Results were compared with those obtained using the conventional lacZ viral plaque assay on the same samples. DS detected significant increases in mutation frequencies and changes to mutation spectra at all PRC doses. Low intra-group variability within DS samples allowed for detection of increases at lower doses than the lacZ assay. While the lacZ assay initially yielded a higher fold-change in mutant frequency than DS, inclusion of clonal mutations in DS mutation frequencies reduced this discrepancy. Power analyses suggested that three animals per dose group and 500 million duplex base pairs per sample is sufficient to detect a 1.5-fold increase in mutations with > 80% power. Overall, we demonstrate several advantages of DS over classical mutagenicity assays and provide data to support efforts to identify optimal study designs for the application of DS as a regulatory test.


Assuntos
Medula Óssea , Taxa de Mutação , Masculino , Camundongos , Animais , Procarbazina/toxicidade , Mutagênicos/toxicidade , Mutação , Testes de Mutagenicidade/métodos , Camundongos Transgênicos , Óperon Lac
4.
Front Immunol ; 14: 1133899, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36865554

RESUMO

Radiotherapy is the major treatment of non-small cell lung cancer (NSCLC). The radioresistance and toxicity are the main obstacles that leading to therapeutic failure and poor prognosis. Oncogenic mutation, cancer stem cells (CSCs), tumor hypoxia, DNA damage repair, epithelial-mesenchymal transition (EMT), and tumor microenvironment (TME) may dominate the occurrence of radioresistance at different stages of radiotherapy. Chemotherapy drugs, targeted drugs, and immune checkpoint inhibitors are combined with radiotherapy to treat NSCLC to improve the efficacy. This article reviews the potential mechanism of radioresistance in NSCLC, and discusses the current drug research to overcome radioresistance and the advantages of Traditional Chinese medicine (TCM) in improving the efficacy and reducing the toxicity of radiotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Reparo do DNA , Sistemas de Liberação de Medicamentos , Transição Epitelial-Mesenquimal , Microambiente Tumoral
5.
Antioxid Redox Signal ; 38(10-12): 747-767, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36242096

RESUMO

Aims: Radiation by-radiation effect (RIBE) can induce the genomic instability of bone marrow mesenchymal stem cells (BMSCs) adjacent to lung cancer, and this effect not only exists in the short-term, but also accompanies it in the long-term, but its specific mechanism is not clear. Our goal is to explore the similarities and differences in the mechanism of genomic damage in tumor-associated BMSCs induced by short-term and long-term RIBE, and to provide a theoretical basis for adjuvant drugs for protection against RIBE at different clinical time periods. Results: We found that both short- and long-term RIBE induced genomic instability. We could show a high expression of TGF-ß1, TNF-α, and HIF-1α in tumor-associated BMSCs after short-term RIBE whereas only TNF-α and HIF-1α expression was increased in long-term RIBE. We further confirmed that genomic instability is associated with the activation of the HIF-1α pathway and that this is mediated by TNF-α and TGF-ß1. In addition, we found differences in the mechanisms of genomic instability in the considered RIBE windows of analysis. In short-term RIBE, both TNF-α and TGF-ß1 play a role, whereas only TNF-α plays a decisive role in long-term RIBE. In addition, there were differences in BMSC recruitment and genomic instability of different tissues with a more pronounced expression in tumor and bone marrow than compared to lung. Innovation and Conclusion: We could show dynamic changes in the expression of the cytokines TGF-ß1 and TNF-α during short- and long-term RIBE. The differential expression of the two is the key to causing the genomic damage of tumor-associated BMSCs in the considered windows of analysis. Therefore, these results may serve as a guideline for the administration of radiation protection adjuvant drugs at different clinical stages. Antioxid. Redox Signal. 38, 747-767.


Assuntos
Efeito Espectador , Instabilidade Genômica , Células-Tronco Mesenquimais , Fator de Crescimento Transformador beta1 , Fator de Necrose Tumoral alfa , Efeito Espectador/efeitos da radiação , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Células-Tronco Mesenquimais/efeitos da radiação , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Células A549 , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Apoptose/genética , Animais , Camundongos , Camundongos Endogâmicos C57BL
6.
Ying Yong Sheng Tai Xue Bao ; 33(4): 887-893, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543038

RESUMO

An indoor potted experiment was carried out to study the application effects of water-based waste drilling mud (WBDM) and drill cuttings combined with humic acid and woody peat in aeolian sandy soil.We analyze their effects on the growth of spinach, in order to provide a reference for the resource utilization of drilling waste and the improvement of aeolian sandy soil. A total of three individual experiments were set up: 4 treatments in the basic group, taking aeolian sandy soil as the control (CK), mixing aeolian sandy soil and drill cuttings at a mass ratio of 1:1, then added with 0, 2%, and 4% WBDM (dry basis) respectively. The basic group treatment was added with 1% humic acid, 1% humic acid+3% woody peat mixture respectively, as the humic acid group and woody peat group. The results showed that in the basic group, drilling waste application significantly increased soil organic matter content (SOM), pH and electrical conductivity, the 2% WBDM significantly promoted the growth of spinach. Humic acid and woody peat reduced soil pH and increased SOM content and electrical conductivity. Plant growth indicators such as plant height, total leaf area, fresh weight and dry weight of the humic acid group were higher than the corresponding treatments in the basic group. The mixed addition of humic acid and woody peat did not affect plant growth. The treatment with the best performance was to add 2% WBDM to the humic acid group, and the SOM was 13.1 g·kg-1, spinach's plant height, total leaf area, fresh weight and dry weight significantly increased by 49.7%, 93.4%, 83.3%, and 34.6% than CK after 40 days of sowing. The application of drilling waste with organic matter could significantly increase SOM content and promote spinach growth. Aeolian sandy soil + drill cuttings + WBDM (2%) + humic acid (1%) was the best combination mode.


Assuntos
Poluentes do Solo , Solo , Substâncias Húmicas , Plantas , Areia , Solo/química , Poluentes do Solo/análise , Spinacia oleracea
7.
Arch Toxicol ; 95(3): 1103-1116, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33506374

RESUMO

The Organisation for Economic Co-Operation and Development Test Guideline 488 (TG 488) uses transgenic rodent models to generate in vivo mutagenesis data for regulatory submission. The recommended design in TG 488, 28 consecutive daily exposures with tissue sampling three days later (28 + 3d), is optimized for rapidly proliferating tissues such as bone marrow (BM). A sampling time of 28 days (28 + 28d) is considered more appropriate for slowly proliferating tissues (e.g., liver) and male germ cells. We evaluated the impact of the sampling time on mutant frequencies (MF) in the BM of MutaMouse males exposed for 28 days to benzo[a]pyrene (BaP), procarbazine (PRC), isopropyl methanesulfonate (iPMS), or triethylenemelamine (TEM) in dose-response studies. BM samples were collected + 3d, + 28d, + 42d or + 70d post exposure and MF quantified using the lacZ assay. All chemicals significantly increased MF with maximum fold increases at 28 + 3d of 162.9, 6.6, 4.7 and 2.8 for BaP, PRC, iPMS and TEM, respectively. MF were relatively stable over the time period investigated, although they were significantly increased only at 28 + 3d and 28 + 28d for TEM. Benchmark dose (BMD) modelling generated overlapping BMD confidence intervals among the four sampling times for each chemical. These results demonstrate that the sampling time does not affect the detection of mutations for strong mutagens. However, for mutagens that produce small increases in MF, sampling times greater than 28 days may produce false-negative results. Thus, the 28 + 28d protocol represents a unifying protocol for simultaneously assessing mutations in rapidly and slowly proliferating somatic tissues and male germ cells.


Assuntos
Mutagênese/efeitos dos fármacos , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Animais , Relação Dose-Resposta a Droga , Células Germinativas/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Mutagênicos/administração & dosagem , Mutação , Fatores de Tempo
8.
Front Immunol ; 12: 810286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069596

RESUMO

The tumor microenvironment is essential for the formation and development of tumors. Cytokines in the microenvironment may affect the growth, metastasis and prognosis of tumors, and play different roles in different stages of tumors, of which transforming growth factor ß (TGF-ß) and tumor necrosis factor α (TNF-α) are critical. The two have synergistic and antagonistic effect on tumor regulation. The inhibition of TGF-ß can promote the formation rate of tumor, while TGF-ß can promote the malignancy of tumor. TNF-α was initially determined to be a natural immune serum mediator that can induce tumor hemorrhagic necrosis, it has a wide range of biological activities and can be used clinically as a target to immune diseases as well as tumors. However, there are few reports on the interaction between the two in the tumor microenvironment. This paper combs the biological effect of the two in different aspects of different tumors. We summarized the changes and clinical medication rules of the two in different tissue cells, hoping to provide a new idea for the clinical application of the two cytokines.


Assuntos
Transformação Celular Neoplásica/metabolismo , Suscetibilidade a Doenças , Neoplasias/etiologia , Neoplasias/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose/genética , Biomarcadores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Transformação Celular Neoplásica/genética , Transição Epitelial-Mesenquimal , Regulação da Expressão Gênica , Instabilidade Genômica , Humanos , Neoplasias/patologia , Ligação Proteica , Transdução de Sinais
9.
Zootaxa ; 4615(2): zootaxa.4615.2.7, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31716347

RESUMO

Four new species of the genus Cicurina are described: C. daweishanensis spec. nov. (female), C. kekei spec. nov. (male and female), C. lichuanensis spec. nov. (male and female) and C. yuelushanensis spec. nov. (male and female). Photos of body and copulatory organs, line drawings of copulatory organs, as well as the locality map are provided. The type specimens of Cicurina eburnata Wang, 1994 were reexamined for the comparison of allied species. Photos of C. calyciforma Wang Xu, 1989 are also presented in order to compare it with two new species.


Assuntos
Aranhas , Distribuição Animal , Animais , China , Feminino , Masculino
10.
Zookeys ; 862: 43-60, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341385

RESUMO

A new Linyphiinae genus Zhezhoulinyphia gen. nov. from Yunnan Province is described together with its two new species: Z.caperata sp. nov. (♂) and Z.denticulata sp. nov. (♂, ♀). Centromerusyadongensis Hu & Li, 1987 is transferred to Zhezhoulinyphia gen. nov. and a new combination, Z.yadongensis (Hu & Li, 1987), comb. nov. is proposed.

11.
Zootaxa ; 4457(4): 589-594, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-30314151

RESUMO

Two new cavernicolous pselaphines, Araneibatrus curvitibialis Yin and Zhou, sp. n. and Tribasodites biyun Yin and Zhou, sp. n., are described from southern China, with diagnostic characters illustrated. Both new species can be readily distinguished from their respective congeners by the male dimorphic features on the antennae, legs, and (or) metaventrite, as well as by the configurations of the aedeagi.


Assuntos
Besouros , Animais , China , Masculino
12.
Biotechniques ; 62(4): 157-164, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28403806

RESUMO

Here, we present a DNA restriction enzyme-based, fluorescent cytosine extension assay (CEA) to improve normalization and technical variation among sample-to-sample measurements. The assay includes end-labeling of parallel methylation-sensitive and methylation-insensitive DNA restriction enzyme digests along with co-purification and subsequent co-measurement of incorporated fluorescence. This non-radioactive, two-color fluorescent CEA (TCF-CEA) was shown to be a relatively rapid and accurate, with 3-fold greater precision than the one-color CEA. In addition, TCF-CEA provided an index of global DNA methylation that was sensitive to differences >5%. TCF-CEA results were highly correlated with LUminometric Methylation Assay (LUMA) results using human liver cell lines (HepG2, HepaRG, HC-04) as well as a human liver primary cell culture. Hypomethylation was observed in cells treated with the de-methylating agent 5-aza-2'-deoxycytidine. These results demonstrate that TCF-CEA provides a simple method for measuring relative degrees of global DNA methylation that could potentially be scaled up to higher-throughput formats.


Assuntos
Bioensaio/métodos , Citosina , Metilação de DNA/genética , Azacitidina/análogos & derivados , Azacitidina/química , Enzimas de Restrição do DNA/genética , Decitabina , Fluorescência , Células Hep G2 , Humanos , Fígado/citologia , Fígado/metabolismo , Cultura Primária de Células
13.
Chinese Circulation Journal ; (12): 1203-1207, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-663091

RESUMO

Objective: To explore the predictors in patients of paroxysmal atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA). Methods: A total of 142 PAF patients received RFCA in our hospital from 2013-03 to 2016-03 were studied. The patients were divided into 2 groups: Recurrence group, n=46 and Non-recurrence group, n=96. Clinical data was compared between 2 groups and AF recurrent predictors were studied by single and multivariate Logistic regression analysis. Based on quartiles of uric acid (UA) level, the patients were categorized in another set of 4 groups: Q1 group, UA<259 μmol/L, n=33, Q2 group, UA 259-320 μmol/L, n=37, Q3 group, UA 321-380 μmol/L, n=37 and Q4 group, UA>380 μmol/L, n=35. The influence of UA on AF recurrence was measured by Kaplan-Meier test, the predictive value of UA combining metabolic syndrome (UA+MS) on AF recurrence was studied by ROC curve analysis. Results: The BMI, diabetes, MS, AF duration, CHADS2 score, creatinine, UA and BNP were different between Recurrence group and Non-recurrence group, all P<0.05. Logistic regression analysis indicated that AF duration (OR=1.02,95% CI 1.01-1.03, P=0.002), UA level (OR=1.01, 95% CI 1.00-1.01, P=0.046) and MS (OR=4.73, 95% CI 1.36-16.45, P=0.014) were the independent predictors for AF recurrence. UA quartile analysis indicated that gender, BMI, MS, creatinine, LVEF and the incidence of AF recurrence had signifcant discrepancy by different UA levels, all P<0.05. ROC curve showed that the predictive values for UA+MS in AF recurrence had the sensitivity at 80.4%, specificity at 74.1% (AUC 0.79±0.04, 95% CI 0.71-0.89, P=0.0001), for UA in AF recurrence had the sensitivity at 73.9%, specificity at 57.2% (AUC 0.66, 95% CI 0.56-0.76, P=0.02); UA+MS had the higher predictive value than UA alone, P<0.05. Conclusion: Both UA and MS were related to AF recurrence, high UA level combining MS had certain predictive value for AF recurrence in PAF patients after RFCA.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 315-9, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25970884

RESUMO

The present manuscript researches the near infrared quantum cutting luminescence phenomena of Yb3+ ion in YVO4 crystal matrix The luminescence spectra, excitation spectra and fluorescence lifetimes were measured. It was found that the excitation of YVO4 crystal matrix energy band by 322.0 nm light can result in the effective secondary cooperative energy transfer of Yba+ ion from the YVO4 crystal matrix It results in the intense 985.5 nm 2F(5/2)-->2F(7/2) near infrared quantum cutting luminescence of Yb3+ ion. Meanwhile, the 430.O nm luminescence intensity of YVO4 crystal matrix decreases greatly. From the experimental measurements, it was found that the lifetime of 430.0 nm fluorescence of (A) Yb(1.5) : YVO4 crystal is tauA = 3.785 s and that of (B) YVO4 crystal is tauB=22.72 s. It was found also that the theoretical efficiency up limit of quantum cutting of (A) Yb(1.5) : YVO4 crystal is about eta1.5%=183-3%.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 325-8, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25970886

RESUMO

The authors present a solar cell model with a three photons quantum-cutting system on the rear surface, then the method of calculation of limiting efficiencies was used to get the maximum efficiency 58.58% at the band gap Eg=0.9315 eV, and in contrast with two-photons quantum-cutting system, it is greatly improved. The result can prove that the three-photons quantum-cutting has a great sense to improve the efficiencies of solar cells. It is the exciting development for us to find out the useful luminescence materials to get the high efficiency.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-292478

RESUMO

<p><b>OBJECTIVE</b>To describe the pregnant women's utilization of prenatal screening for Down's syndrome and its influencing factors.</p><p><b>METHODS</b>From October 2007 to December 2008, 4250 lying-in women in 54 hospitals were surveyed by stratified cluster sampling method in Zhejiang, Hunan and Sichuan, which located in Eastern, Central and Western China, respectively. Demographic characteristics, knowledge and health behaviors were collected by the questionnaire of lying-in women's utilization and influencing factors of prenatal screening for Down's syndrome. Whether to use prenatal screening was determined by the lying-in women's medical history. Chi-square test and logistic regression analysis were used to analyze data.</p><p><b>RESULTS</b>Respondents' age was (26.92 ± 4.60) years old. The total utilization rate of prenatal screening for Down's syndrome was 40.0% (1696/4237), and screening utilization rates in Zhejiang, Hunan and Sichuan were 48.23% (682/1414), 41.73% (616/1476) and 29.55% (398/1347), respectively. Screening utilization rates of respondents with college degree or above and high school or below were 72.68% (697/959) and 30.46% (998/3276), respectively. Screening utilization rates of urban and rural respondents were 63.00% (952/1511) and 27.11% (732/2700), respectively. Screening utilization rates of respondents under 35 years old and over 35 years old were 41.40% (1645/3973) and 19.32% (51/264). All differences were significant (all P values < 0.05). A total of 79.14% (1419/1793) of respondents thought it was necessary to take prenatal screening for Down's syndrome, and 79.47% (1506/1895) of respondents received doctors' suggestions, 24.2% (654/2702) of respondents who heard of prenatal screening for Down's syndrome could figure out the main pathogenic factors, while 23.0% (621/2702) didn't know any factors; 77.8% (2102/2702) of respondents heard of prenatal screening for Down's syndrome, but 12.3% (259/2102) didn't know the appropriate gestational weeks to uptake the screening, 47.0% (988/2102) knew of prenatal screening for Down's syndrome through healthcare providers. Logistic regression analysis result demonstrated that living in Zhejiang (OR = 1.62, 95%CI: 1.26 - 2.08), city residence (OR = 2.06, 95%CI: 1.63 - 2.60), with positive attitude to screening (OR = 5.00, 95%CI: 3.97 - 6.29), pregnant women's age below 35 years old (OR = 3.86, 95%CI: 2.53 - 5.89), receiving advices from healthcare providers (OR = 12.64, 95.0%CI: 9.97 - 16.02), college degree or above educational level (OR = 2.67, 95%CI: 2.03 - 3.50) were facilitating factors on utilization of prenatal screening for Down's Syndrome.</p><p><b>CONCLUSION</b>Pregnant women's use of prenatal screening for Down's syndrome was not enough, and living in zhejiang, higher education level, rural respondents with age under 35 years old, receiving advice from healthcare providers or not and their attitude toward necessity were significant promotive factors of utilization of prenatal screening for Down's syndrome.</p>


Assuntos
Adulto , Feminino , Humanos , Gravidez , Adulto Jovem , China , Síndrome de Down , Análise Fatorial , Diagnóstico Pré-Natal , Métodos
17.
Regul Toxicol Pharmacol ; 60(1): 54-72, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21335049

RESUMO

Gene expression profiling that examines critical, toxicologically-relevant gene and signal-response pathways promises to improve risk assessment and safety evaluation of low-dose chemical exposures. As an approach to achieving this goal, mechanistic interpretations based upon gene expression changes that are determinants of adverse toxicological outcomes were applied to the analysis of low-dose gene expression profiles. RNA for expression profiling was obtained from mice given short-term gavage exposures to diminishing doses of four toxicants: 3,3',4,4',5-pentachlorobiphenyl (PCB126), phenobarbital (PB), isoproterenol (IPR), and lead acetate (PbAc). Lowest doses were below the no-observable effects levels established using standard clinical toxicology parameters. Hepatic gene expression profiles were analyzed using a custom, focused oligonucleotide DNA microarray, the HC ToxArray™, containing toxin-responsive and toxicologically-determinant genes. Expression data were compared to changes in conventional clinical chemistry parameters and drug metabolism activities. PCB126 and PB demonstrated a dose-dependent correlation between minimal changes in biochemical markers, hepatic metabolism and induction of gene expression profiles. PbAc exposure gave a small adaptive profile at the highest dose. IPR- and PCB126-induced changes were detected at doses below those required to alter the traditional biochemical endpoints and included genes with causal roles in hepatic toxicity, insulin resistance, atherosclerosis, angiogenesis and hypertension. Likely adverse phenotypic consequences resulting from expression changes lead to assignments of "Lowest Observed Adverse Transcriptional Expression Levels" (LOATEL) for each agent. These results support the suggestion that altered expression profiles of genes contributing to toxicologically-relevant pathways provide useful tools for reducing uncertainty in establishing no-effect levels and for designing longer-term toxicity studies.


Assuntos
Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Xenobióticos/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Testes de Química Clínica , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Isoproterenol/toxicidade , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Masculino , Camundongos , Camundongos Endogâmicos , Análise em Microsséries , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Análise de Sequência com Séries de Oligonucleotídeos , Tamanho do Órgão/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Fenobarbital/toxicidade , Bifenilos Policlorados/toxicidade , RNA Mensageiro/metabolismo
18.
National Journal of Andrology ; (12): 30-32, 2007.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-289052

RESUMO

<p><b>OBJECTIVE</b>To assess the diagnostic value of alpha-glycosidase for epididymal lump induced obstructive azoospermia.</p><p><b>METHODS</b>Seventy-six infertile men with normal spermatogenic function were divided according to sperm density into a normal density group (n = 27), an oligospermia group (n = 21) and an obstructive azoospermia group (n = 28), and another 30 fertile males were included as normal controls. Semen plasma alpha-glycosidase, leucocyte count, sexual hormone levels and the diameters of the epididymal lumps were measured and their correlations were analyzed.</p><p><b>RESULTS</b>alpha-Glycosidase in the obstructive azoospermia group was significantly lower than that of the other groups (P <0.05), and negatively correlated with epididymal volume (r = -0.417, P <0.05) and leucocyte count (r = -0.342, P <0.05).</p><p><b>CONCLUSION</b>Alpha-Glycosidase has been proved of diagnostic value for epididymal obstructive azoospermia.</p>


Assuntos
Adulto , Humanos , Masculino , Epididimo , Doenças dos Genitais Masculinos , Diagnóstico , Oligospermia , Diagnóstico , Contagem de Espermatozoides , Motilidade dos Espermatozoides , alfa-Glucosidases
19.
BMC Genomics ; 7: 266, 2006 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-17052352

RESUMO

BACKGROUND: Microarray normalizations typically apply methods that assume absence of global transcript shifts, or absence of changes in internal control features such as housekeeping genes. These normalization approaches are not appropriate for focused arrays with small sets of genes where a large portion may be expected to change. Furthermore, many microarrays lack control features that can be used for quality assurance (QA). Here, we describe a novel external control series integrated with a design feature that addresses the above issues. RESULTS: An EC dilution series that involves spike-in of a single concentration of the A. thaliana chlorophyll synthase gene to hybridize against spotted dilutions (0.000015 to 100 microM) of a single complimentary oligonucleotide representing the gene was developed. The EC series is printed in duplicate within each subgrid of the microarray and covers the full range of signal intensities from background to saturation. The design and placement of the series allows for QA examination of frequently encountered problems in hybridization (e.g., uneven hybridizations) and printing (e.g., cross-spot contamination). Additionally, we demonstrate that the series can be integrated with a LOWESS normalization to improve the detection of differential gene expression (improved sensitivity and predictivity) over LOWESS normalization on its own. CONCLUSION: The quality of microarray experiments and the normalization methods used affect the ability to measure accurate changes in gene expression. Novel methods are required for normalization of small focused microarrays, and for incorporating measures of performance and quality. We demonstrate that dilution of oligonucleotides on the microarray itself provides an innovative approach allowing the full dynamic range of the scanner to be covered with a single gene spike-in. The dilution series can be used in a composite normalization to improve detection of differential gene expression and to provide quality control measures.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência com Séries de Oligonucleotídeos/normas , Animais , Arabidopsis/genética , Artefatos , Canadá , Reações Falso-Negativas , Reações Falso-Positivas , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Controle de Qualidade , RNA Complementar/genética , RNA Mensageiro/genética , Ratos , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Talanta ; 70(3): 533-9, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970804

RESUMO

It is difficult to detect glucose by surface-enhanced Raman spectroscopy (SERS) due to the small normal Raman cross-section and the weak adsorption of glucose molecules on the surface of noble metal. A simple and fast method is proposed in this paper for the detection of glucose based on SERS signal of the enzyme reaction product and the difficulties have been circumvented. Gold colloids modified by horseradish peroxidase and glucose oxidase (HRP/GOD-gold colloids) are added to the mixture of o-phenylenediamine and glucose, and the resulting solution is allowed to react at room temperature for 5min. Azoaniline, an azo compound with strong Raman scattering, is generated and the Raman scattering of this reaction product is enhanced when adsorbed on gold colloids. The intensity of the SERS spectrum is used for assessment of glucose content. The dynamic signal range provided by this analytical system is 0.50-32mM, which covers the normal clinical range for glucose in blood from 3.5 to 6.1mM. The detection limit is about 0.46mM. The interference effect of several proteins on glucose detection is also investigated and has shown to have no effect on the measurement of glucose by the described technique.

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