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1.
Plant Dis ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468140

RESUMO

Morel mushrooms (Morchella spp.) are highly regarded globally for their distinctive texture and savory flavor. In 2022, the cultivation area for morel mushrooms in China reached nearly 20,000 hectares, with predominant cultivars including M. sextelata, M. importuna and M. exima (Bian et al., 2024). In March 2022, however, deformities of friting bodies were observed in M. importna at morel mushroom farms in Huaihua city (28.43°N, 110.47°), China, with an incidence rate ranging from 5% to 10%. The disease symptoms begin with the invasion of the hymenium of morel mushroom by white cotton-like mycelia, ultimately resulting in halted fruiting body growth and the manifestation of anomalous fruiting body morphology. Infected samples were collected from the morel growers. Following sterilization with 75% ethanol of the surrounding tissue of infected samples, the white hyphae from the morel lesions were picked out using a dissecting needle, and incubated onto potato saccharose agar medium supplemented with 60 mg/L streptomycin at 25°C. Studies showed that seven out of nine fungal isolates exhibiting identical morphological features rapidly grew on the same culture medium described above, reaching a length of 75 mm in 4 to 5 days at 25°C. The white and thick hyphal colonies of these isolates gradually filled with brown spore powder. Generally, the conidia of the hyphal colonies were polyblastic with protrusions at the tips, measuring 75 to 165 × 36 to 50 µm (n = 30) in width and length, displaying colors varying from light reddish brown to grayish brown, and possessing one or five septa. To confirm the identity of the pathogen, the region of the internal transcribed spacer region (ITS), 28S nuclear ribosomal large subunit (LSU), and RNA polymerase II second largest subunit (rpb2) genes of the representative isolate H2 were amplified by PCR (Taguiam, et al. 2021). The generated ITS (OR338304), rpb2 (OR452112) and LSU (OR338334) from the isolate H2 had 98-100% similarity to the Alternaria alternata strains ATCC 6663 and CBS 880.95 in BLASTn analysis. ITS, rpb2 and LSU sequences were assembled using Sequence Matrix, and their homogeneity was assessed with PAUP (Vaidya et al., 2011). Bayesian (MrBayes-3.2.7a) and maximum-likelihood (RAxML1.3.1) methods, utilizing the best fit GTR+G+I model obtained from MrModeltest 2.3, were employed for phylogenetic analysis (Aveskamp et al. 2010). Based on morphological characteristics and phylogenetic analysis, the isolate H2 was identified as A. alternata. In the second year post-disease, disease-free morels, with a height of 3 cm, were cultivated in field greenhouses and used for test. A 15 ml suspension (1 × 106 conidia/ml) was applied to 15 young fruiting bodies and their corresponding substrate soil. The results showed that the reappearance of white cotton-like mycelia and deformed M. importuna fruiting bodies within 7 days post-inoculation with the spore suspension, as opposed to the controls. The isolates (H2-1, H2-2 and H2-3) were reisolated from the infected tissues and identified as A. alternata based on its morphological features and phylogenetic analyses. In this study, a similar investigation was previously conducted on cultivated quinoa (Chenopodium quinoa) in Eastern Denmark (Colque-Little et al., 2023). This study marks the first documentation of A. alternata causing deformities in M. importuna fruiting bodies. These deformities occur under conditions of high-temperature (>22°C) and high humidity (>88%). Our findings provide crucial insights for managing A. alternata in M. importuna cultivation in China.

2.
Exp Cell Res ; 404(1): 112618, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33965401

RESUMO

Androgenetic alopecia (AGA) is the most common type of hair loss dysfunction. Secreted frizzled related protein 1 (SFRP1) is found to be associated with hair loss, but its role in AGA and the regulation mechanism of its transcription level is unclear. The aim of our study is to explore the expression of SFRP1 in AGA samples and its transcriptional mechanism. Male frontal and occipital scalp hair follicles from AGA patients were collected, and human dermal papilla cells (DPCs) were isolated and cultured. SFRP1 gene was cloned and constructed into recombinant plasmids to perform dual-luciferase reporter assay. Transcription factor binding sites were predicted through the Jaspar website and further confirmed by the chromatin immunoprecipitation (ChIP) assay. Expression of genes in DPCs was determined by immunofluorescence (IF) staining, quantitative real-time PCR (qRT-PCR) and western blotting. Our findings showed that SFRP1 was highly expressed in DPCs of AGA patients. The core promoter region of SFRP1 was from -100 to +50 bp and was found to be positively regulated by forkhead box C1 (FOXC1), a transcription factor related to hair growth, both at mRNA and protein level in DPCs. Our study suggests that FOXC1 plays an important role in regulating SFRP1 transcription, which may provide new insights into the development of therapeutic strategies for the treatment of AGA.


Assuntos
Alopecia/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Folículo Piloso/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Membrana/metabolismo , Alopecia/tratamento farmacológico , Alopecia/genética , Derme/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Fatores de Transcrição/metabolismo
4.
Educ Policy (Los Altos Calif) ; 32(6): 755-796, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38882604

RESUMO

A growing body of research examines the role of elite networks, power, and race in the advocacy for market-based reforms and their ultimate effects on students, teachers, and communities of color. Yet, less research explores how such reforms interact with gender in the workplace, especially how policies such as school choice, competition, and incentive-based pay impact female actors within K-12 schools (e.g., teachers, school leaders). The current research on marketization and privatization in education has largely overlooked the potential impact on women in schools. We review the literature on women in K-12 education and in the economy more generally, and organize it conceptually to identify areas for future inquiry. After synthesizing and summarizing themes across diverse bodies of literature, we contend that as schools privatize, we may see greater gender disparities in education leadership and teaching.

5.
Mol Cancer ; 12(1): 172, 2013 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-24365180

RESUMO

BACKGROUND: The exposure of skin keratinocytes to Ultraviolet (UV) irradiation leads to Akt phosphorylation at Ser-473, which is important for the carcinogenic effects of excessive sun exposure. The present study investigated the underlying mechanism of Akt Ser-473 phosphorylation by UVB radiation. RESULTS: We found that DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and mammalian target of rapamycin (mTOR) complex 2 (mTORC2) were both required for UVB-induced Akt Ser-473 phosphorylation in keratinocytes. Inhibition of DNA-PKcs activity via its inhibitor NU7026, a dominant-negative kinase-dead mutation, RNA interference (RNAi) or gene depletion led to the attenuation of UVB-induced Akt Ser-473 phosphorylation. Meanwhile, siRNA silencing or gene depletion of SIN1, a key component of mTORC2, abolished Akt Ser-473 phosphorylation by UVB. Significantly, we discovered that DNA-PKcs was associated with SIN1 in cytosol upon UVB radiation, and this complexation appeared required for Akt Ser-473 phosphorylation. Meanwhile, this DNA-PKcs-SIN1 complexation by UVB was dependent on epidermal growth factor receptor (EGFR) activation, and was disrupted by an EGFR inhibitor (AG1478) or by EGFR depletion. UVB-induced complexation between DNA-PKcs and mTORC2 components was also abolished by NU7026 and DNA-PKcs mutation. Finally, we found that both DNA-PKcs and SIN1 were associated with apoptosis resistance of UVB radiation, and inhibition of them by NU7026 or genetic depletion significantly enhanced UVB-induced cell death and apoptosis. CONCLUSION: Taken together, these results strongly suggest that DNA-PKcs-mTORC2 association is required for UVB-induced Akt Ser-473 phosphorylation and cell survival, and might be important for tumor cell transformation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína Quinase Ativada por DNA/metabolismo , Queratinócitos/enzimologia , Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional/efeitos da radiação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Raios Ultravioleta , Animais , Apoptose/efeitos da radiação , Linhagem Celular Transformada , Sobrevivência Celular/efeitos da radiação , Cromonas/farmacologia , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Ativação Enzimática , Receptores ErbB/metabolismo , Humanos , Queratinócitos/fisiologia , Queratinócitos/efeitos da radiação , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos , Morfolinas/farmacologia , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Fosforilação , Cultura Primária de Células , Tolerância a Radiação , Pele/patologia , Neoplasias Cutâneas/enzimologia , Serina-Treonina Quinases TOR/metabolismo
6.
Huan Jing Ke Xue ; 34(1): 98-107, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23487924

RESUMO

Sediment quality criterion (SQC) is the concentrations of sediment-associated contaminants that are unlikely to be associated with sediment toxicity or other adverse effects on benthic invertebrates. Thus, the derivation of SQC is crucial to protect benthic invertebrates, and can serve as the tool for scientific sediment management. Sediment, interstitial water, and plant samples were collected at 43 sampling sites from the Xiangjiang River, and metal concentrations were determined. Based on equilibrium partitioning approach, spiked sediment toxicity approach using Hyalella azteca, and background value approach, SQC for Cd and Hg in the Xiangjiang River was derived. Results showed that, SQC-L for Cd and Hg in the Xiangjiang River were 1.89 mg x kg(-1) and 0.13 mg x kg(-1) respectively, and SQC-H were 28.32 mg x kg(-1) and 0.79 mg x kg(-1) respectively. SQC were comparable to those in previous studies. Also, the reasonability of SQC was demonstrated by the heavy metal concentrations in plants, matching sediment chemistry and toxicity data for benthic invertebrates in the Xiangjiang River. To assess the sediment quality of Xiangjiang, metal concentrations in sediment samples were compared with the SQC. It was found that the proportion of sampling sites with Cd and Hg concentrations lower than SQC-L or higher than SQC-H was low, and 74.4% and 76.7% of sampling sites showed Cd and Hg concentrations between SQC-L and SQC-H.


Assuntos
Cádmio/análise , Sedimentos Geológicos/química , Mercúrio/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , Cádmio/toxicidade , China , Monitoramento Ambiental/métodos , Invertebrados/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
7.
Huan Jing Ke Xue ; 33(8): 2691-700, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23213892

RESUMO

Microbial community structure and biomass in river water can reflect the situation of water quality in some extent. Nitrogen removal was mainly achieved by the nitrification and denitrification processes, and ammonia oxidation catalyzed by ammonia-oxidizing bacteria (AOB) is the first and rate-limiting step of nitrification. To explore the AOB community structure and biomass in nitrogen polluted river, water samples were collected from Buji River (Shenzhen) in wet season. Quantification of 16S rRNA copy numbers of total bacteria and AOB were performed by real-time PCR, and the microbial community structures were studied by denaturing gradient gel electrophoresis (DGGE). The results showed that the number of total bacterial 16S rRNA changed from 4.73 x 10(10) - 3.90 x 10(11) copies x L(-1) in the water samples. The copy numbers of AOB varied from 5.44 x 10(6) - 5.96 x 10(8)copies x L(-1). Redundancy discrimination analysis (RDA) showed that the main factors affecting the structure and the numbers of bacteria were different. For total bacteria, nitrate influenced the biomass significantly (P < 0.05) while nitrogen and heavy metals (Mn and Zn) were the main factors affecting the microbial community structures (P < 0.05). For AOB, ammonia and Zn were the main factors influencing the biomass while ammonia nitrogen and heavy metals (Mn and Zn) were the main factors affecting the microbial community structures. 16S rDNA sequences from the water samples indicated that the bacteria generally belonged to Epsilon-Proteobacteria, Gamma-Proteobacteria, Beta-Proteobacteria, and Delta-Proteobacteria. Nitrosomonas sp. and Nitrosospira sp. were the main AOB. Cluster analysis showed that water pollution in downstream resulted in evident difference in microbial community structure between upstream and downstream water samples.


Assuntos
Nitrogênio/metabolismo , Nitrosomonas/metabolismo , Proteobactérias/metabolismo , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Amônia/isolamento & purificação , Amônia/metabolismo , Bactérias/metabolismo , China , Nitrificação , Nitritos/isolamento & purificação , Nitritos/metabolismo , Nitrogênio/isolamento & purificação , Nitrosomonas/isolamento & purificação , Proteobactérias/isolamento & purificação , Rios , Estações do Ano , Poluentes Químicos da Água/isolamento & purificação
8.
Cell Signal ; 24(9): 1781-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22584119

RESUMO

We demonstrate here that a relative low dose of perifosine significantly enhanced UVB-induced apoptosis in skin cells (keratinocytes and fibroblasts), associated with a significant increase of reactive oxygen species (ROS) and ceramide production as well as multiple perturbations of diverse cell signaling pathways, shifting to a significant pro-apoptosis outcomes. Perifosine inhibited UVB-induced pro-survival Akt/mammalian target of rapamycin (mTOR) and ERK activation, while facilitating pro-apoptotic AMP-activated protein kinas (AMPK), c-Jun-NH(2)-kinase (JNK), and p53 activation; these signaling changes together promoted a striking increase in skin cell apoptosis and a significantly reduced amount of DNA damages. Our results suggest that perifosine may represent a novel skin cancer prevention strategy.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Fosforilcolina/análogos & derivados , Neoplasias Cutâneas/prevenção & controle , Pele/citologia , Pele/efeitos dos fármacos , Raios Ultravioleta , Células Cultivadas , Ceramidas/biossíntese , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Fosforilcolina/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
9.
Biochem Biophys Res Commun ; 421(3): 462-7, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22507982

RESUMO

The aim of the current study is to investigate the effect of ceramides on genistein-induced anti-melanoma effects in vitro. We found that exogenously added cell-permeable short-chain ceramides (C6) dramatically enhanced genistein-induced growth inhibition and apoptosis in cultured melanoma cells. Genistein treatment only induced a moderate intracellular ceramides accumulation in B16 melanoma cells. Two different agents including 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), a ceramide glucosylation inhibitor, and the sphingosine kinase-1 (SphK1) inhibitor II (SKI-II), a sphingosine (ceramides precursor) phosphorylation inhibitor, both facilitated genistein-induced ceramides accumulation and melanoma cell apoptosis. Co-administration of ceramide (C6) and genistein induced a significant Akt inhibition and c-jun-NH(2)-kinase (JNK) activation, caspase-3 cleavage and cytochrome c release. Caspase-3 inhibitor z-DVED-fmk, JNK inhibitor SP 600125, or to restore Akt activation by introducing a constitutively active form of Akt (CA-Akt) diminished ceramide (C6) and genistein co-administration-induced in vitro anti-melanoma effect. Our study suggests that increasing cellular level of ceramides may sensitize genistein-induced anti-melanoma effects.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ceramidas/farmacologia , Resistencia a Medicamentos Antineoplásicos , Genisteína/farmacologia , Melanoma/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ceramidas/biossíntese , Ativação Enzimática , Humanos , MAP Quinase Quinase 4/biossíntese , Melanoma Experimental/patologia , Camundongos , Morfolinas/farmacologia , Tiazóis
10.
Huan Jing Ke Xue ; 32(4): 1146-53, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21717761

RESUMO

The heavy metal (Pb, Zn, Cr, Cu, Cd, and Hg) concentrations in the A horizon and C horizon soils, collected around the Pb/Zn mining and smelting area of Shuikoushan in Hunan, China, were investigated, and the Pb isotopic compositions were also determined to identify the potential origin of Pb in the A horizon soil. Compared with C horizon soils, the A horizon soils exhibit elevated heavy metal concentrations, especially in the vicinity of the mining and smelting area. This reveals that the surface soil was contaminated to some degree. The contents of Pb, Zn, Cr, Cu, Cd, and Hg in soils are up to 3966.88, 2086.25, 135.31, 185.63, 56.15, and 16.434 mg/kg, respectively. The potential risks caused by different metals are in the order of Cd > Hg > Pb > Cu > Zn = Cr. Much higher potential ecological risk was observed for the central area (Shuikoushan Pb/Zn mining and smelting area) than for the surrounding area. About 34%, 33%, 11%, and 22% of the sampling sites demonstrate low, moderate, considerable, and very high potential ecological risk in the central area, while about 68%, 16%, 10%, and 6% of the sampling sites show low, moderate, considerable, and very high potential ecological risk in the surrounding area, respectively. Compared with the Pb isotopic compositions in the C horizon soils (206Pb/207Pb 1.168-1.246, 208 Pb/206 Pb 2.014-2.130), the Pb in the A horizon soils has lower 206 Pb/207Pb ratios (1.166-1.226) and higher 208Pb/206Pb ratios (2.043-2. 135). The Pb in the A horizon soils predominantly derives from two-component mixing resources. One is the parent materials of C horizon, and the other is the atmospheric deposition of the smelting flue gas dust.


Assuntos
Radioisótopos de Chumbo/análise , Chumbo , Metais Pesados/análise , Poluentes do Solo/análise , Zinco , China , Monitoramento Ambiental , Mineração
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 18(5): 1211-9, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21129263

RESUMO

The study was aimed to explore the effects of T-bet (T-box expressed in T cell), GATA-3(GATA binding protein 3) and relevant signal transduction pathways on the immune-related pathogenesis of chronic aplastic anemia (CAA), and to investigate the immunological regulation mechanism in the treatment of CAA by using cyclosporine A (CsA) at the level of Th cell imbalance, transcriptional factors, and relevant signal pathways. The real-time fluorescent quantitative polymerase chain reaction (real-time FQ-PCR) was used to determine the mRNA expression of T-bet, GATA-3, signal transducers and activators of transcription 4 (STAT4) and signal transducers and activators of transcription 6 (STAT6) in peripheral blood mononuclear cell (PBMNC) of CAA patients before and after treatment with CsA; the flow cytometry (FCM) and enzyme linked immunosorbent assay (ELISA) were used to determine the Th1/Th2 proportion in peripheral blood, and levels of IFN-γ, IL-12 and IL-4 in PBMNC-cultured supernatant. Healthy people were included to test the above indexes. The results showed that the mRNA expression of PBMNC T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion, Th1/Th2 ratio and levels of IFN-γ and IL-12 in PBMNC-cultured supernatant of CAA patients were significantly higher than those of healthy people (p < 0.01). After treating with CsA for 6 months of CsA treatment, expression of T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion, IFN-γ and IL-12 levels were lower than before, however, the expression of T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion and IFN-γ had not been reduced to normal state. Compared to healthy people, no significant difference existed in the mRNA expression of GATA-3, STAT6, Th2 proportion, as well as level of IL-4 before and after treatment (p>0.05). It is concluded that the abnormal activation of IFN-γ/T-bet and IL-12/STAT4 pathways, as well as Th balance deviating to Th1 excursion play vital roles in the immunological pathogenesis of AA. CsA lowers the abnormal activation of IFN-γ/T-bet and IL-12/STAT4 pathways to correct Th1 hyperpolarization, which may reduce the abnormally activated cell-mediated immunity and relax hematopoietic depression of AA patients.


Assuntos
Anemia Aplástica/tratamento farmacológico , Ciclosporina/farmacologia , Fator de Transcrição GATA3/metabolismo , Proteínas com Domínio T/metabolismo , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Adolescente , Adulto , Idoso , Anemia Aplástica/imunologia , Anemia Aplástica/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-12/metabolismo , Interleucina-4/metabolismo , Masculino , Pessoa de Meia-Idade , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais , Adulto Jovem
12.
J Hazard Mater ; 154(1-3): 595-601, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18053644

RESUMO

Bottom ash, a power plant waste, was used to remove the organic pollutants in coking wastewater and papermaking wastewater. Particular attention was paid on the effect of bottom ash particle size and dosage on the removal of chemical oxygen demand (COD). UV-vis spectra, fluorescence excitation-emission matrix (FEEM) spectra, Fourier transform infrared (FTIR) spectra, and scanning electron microscopic (SEM) photographs were investigated to characterize the wastewaters and bottom ash. The results show that the COD removal efficiencies increase with decreasing particle sizes of bottom ash, and the COD removal efficiency for coking wastewater is much higher than that for papermaking wastewater due to its high percentage of particle organic carbon (POC). Different trends of COD removal efficiency with bottom ash dosage are also observed for coking and papermaking wastewaters because of their various POC concentrations. Significant variations are observed in the FEEM spectra of wastewaters after treatment by bottom ash. New excitation-emission peaks are found in FEEM spectra, and the fluorescence intensities of the peaks decrease. A new transmittance band in the region of 1400-1420 cm(-1) is observed in FTIR spectra of bottom ash after adsorption. The SEM photographs reveal that the surface of bottom ash particles varies evidently after adsorption.


Assuntos
Coque , Resíduos Industriais , Papel , Centrais Elétricas , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/química , Adsorção , Carbono/análise , Cor , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Huan Jing Ke Xue ; 28(6): 1324-31, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17674744

RESUMO

The concentrations of total organic carbon (TOC) and the NaOH extracted humic substances were analyzed in three size fractions (I : 100 - 300 microm, II : 63 - 100 microm and III : < 63 microm) of sediments sampled in the middle Yellow River. Moreover, UV-visible absorption spectra, fourier transform infrared spectra (FTIR) and three-dimensional excitation emission matrix fluorescence spectra (3DEEM) were used to characterize the chemical structures of the NaOH extracted humic substances in three sediment size fractions. The results show that sediment organic matter in all the size fractions of the collected sediments is dominated by humic substances absorbed on the clay minerals. The proportions of the NaOH extracted humic substances to TOC decrease with decreasing sediment grain size ( I > II > III). This may result from the stronger interaction of the humic substances with clay minerals in finer size fractions of the colleted sediments. Similar UV-visible spectra with different absorbance intensity are observed for the NaOH extracted humic substances in three sediment size fractions. The infrared spectra of the NaOH extracted humic substances show five strong peaks in all fractions of the samples. The area ratios of FTIR peaks suggest that the contents of the phenolic, alcoholic and carboxylic groups account for more than 75% in the NaOH extracted humic substances. Three characteristic excitation-emission peaks present in the 3DEEM of the NaOH extracted humic substances: peak A (UV humic-like compounds), peak C (visible humic-like compounds) and peak T'(phenolic compounds or protein like compounds). UV-visible, FTIR and 3DEEM results imply that the aromatic degree of the NaOH extracted humic substances is higher in fractions I and II than in fraction III. The results also indicate that the aliphatic and aromatic contents are higher in fractions I and II, whilst the phenolic, alcoholic and carboxylic contents are higher in fraction III.


Assuntos
Água Doce/análise , Sedimentos Geológicos/análise , Substâncias Húmicas/análise , China , Sedimentos Geológicos/química , Tamanho da Partícula , Rios , Hidróxido de Sódio/química , Espectrometria de Fluorescência
14.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 29(2): 213-6, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17536271

RESUMO

OBJECTIVE: To explore the effects of antisense epidermal growth factor receptor (EGF-R) oligodeoxynucleotides on ultraviolet-induced c-jun activity of keratinocytes after EGF-R oligodeoxynucleotides transfect to HaCaT in vitro. METHODS: c-jun DNA binding activity after ultraviolet-B (UVB) irradiation and EGF-R oligodeoxynucleotides transfection were determined with a highly sensitive and specific colorimetric method. After EGF-R oligodeoxynucleotides transfection, the mRNA level of EGF-R was detected by reverse transcription polymerase chain reaction method. RESULTS: Compared with control groups, c-jun activity increased significantly in UVB (10, 20, 30 mJ/cm2) irradiation groups (P < 0.05). EGF-R mRNA and c-jun activities induced by UVB were inhibited after the keratinocytes were transfected with EGF-R antisense oligodeoxynucleotides at 2, 4 and 8 microg/ml concentrations (P < 0.01). CONCLUSION: The ultraviolet-induced c-jun activity of keratinocytes can be mediated by EGF-R and inhibited by EGF-R antisense oligodeoxynucleotides, which is transfected to keratinocytes and mediated by lipofectamine.


Assuntos
Receptores ErbB/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Linhagem Celular , Receptores ErbB/biossíntese , Humanos , Queratinócitos/metabolismo , Transfecção , Raios Ultravioleta
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