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1.
Molecules ; 24(17)2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31454968

RESUMO

In this work, a highly selective fluorescent chemosensor N-(2-(2-butyl-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-6-yl)hydrazine-1-carbonothioyl)benzamide (L) was prepared and characterized. An assay to detect the presence of cobalt(II) ions was developed by utilizing turn-on fluorescence enhancement with visual colorimetric response. Upon treatment with Co2+, a remarkable fluorescence enhancement located at 450 nm was visible to naked eyes accompanied with a distinct color change (from pink to colorless) in a CH3CN/HEPES (4/1, v/v, pH = 7.4) solution due to the formation of a 1:1 complex at room temperature. In addition, the linear concentration range for Co2+ was 0-25 µM with the limit of detection down to 0.26 µM. Thus, a highly sensitive fluorescent method based on chelation-assisted fluorescence enhancement was developed for the trace-level detection of Co2+. The sensor was found to be highly selective toward Co2+ ions with a large number of coexisting ions. Furthermore, the L probe can serve as a fluorescent sensor for Co2+ detecting in biological environments, demonstrating its low toxic properties to organisms and good cell permeability in live cell imaging.

2.
J Hazard Mater ; 381: 120966, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31404892

RESUMO

Pesticides, which can accumulate in soil, water, animals and plants, are essential to world agriculture. Developing a method that can efficiently and quickly detect toxic pesticides is of importance but still a challenge. Here, two luminescent dye@MOFs systems, Rho B@1 and Rho 6G@1, were successfully fabricated based on [Cd2(tib)(btb)(H2O)2]∙NO3∙2DMF (1). This work is the first use of two fluorescent sensors as dual-emitting platforms for detecting pesticides. As a result, the fluorescence intensity ratios between the two main emissions can be tuned using the concentrations of the dye solutions, and the emissions are at 370 nm/606 nm and 370 nm/590 nm for Rho B@1 and Rho 6G@1, respectively. The intensities of the two main emissions of Rho B@1 and Rho 6G@1 are also influenced by the chemical structures of pesticides with electron-withdrawing groups. It is important that high sensitivity and selectivity for sensing pesticides must have good recyclability. Rho B@1 and Rho 6G@1 can still remain stable regarding the detection of nitenpyram even after 5 cycles, with LODs of 0.48 nM for Rho B@1 and 3 nM for Rho 6G@1, which indicate that these two luminescent dye@MOFs systems are excellent fluorescence probe candidates for the selective detection of pesticides.

3.
Molecules ; 24(12)2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31226827

RESUMO

Isomers provide more possibilities for the structure of organic compounds. Molecular structures determine their corresponding properties, therefore the intrinsic relationship between structure and properties of isomers is of great research value. Isomers with a stable structure and excellent performance possess more potential for development and application. In this paper, we design and synthesize structural isomers with different molecular symmetries based on the asymmetric structure of imidazole and the symmetrical structure of pyrene. Isomers with stable molecular structures can be obtained by a simple and efficient "one-pot" reaction, involving axisymmetric configuration and centrosymmetric configuration. Using this "click-like" reaction, the structure of target molecules is controllable and adjustable. Furthermore, the effect of molecular configurations on molecular stacking of crystal is studied. The variation of the optical and thermal properties, the optimized structures, and orbital distributions of isomers depends on different molecular geometry with different symmetry, which are revealed by crystallographic analysis. This present strategy provides an efficient synthetic method for the design and synthesis of structural isomers based on pyrene-imidazole.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117242, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31207489

RESUMO

An effective morpholine-type naphthalimide chemsensor, N-p-chlorophenyl-4-(2-aminoethyl)morpholine-1,8-naphthalimide (CMN) has been developed as a lysosome-targeted fluorometric sensor for trivalent metal ions (Fe3+, Al3+ and Cr3+). Upon the addition of Fe3+, Al3+ or Cr3+ ions, the probe CMN showed an evident naked-eye color changes which pale yellow solution of CMN turned deepened and it displayed turn-on fluorescence response in methanol. CMN showed a significant selective and sensitive toward Fe3+, Al3+ or Cr3+ ions, while there was no obvious behavior to other monovalent or divalent metal ions from the UV-vis and fluorescence spectrum. Based on the Job's plot analyses the 1:1 coordination mode of CMN with Fe3+, Al3+ or Cr3+ was proposed. The limit of detection (LOD) observed were 0.65, 0.69 and 0.68 µM for Fe3+, Al3+ and Cr3+ ions, respectively. The N-atom of morpholine directly involved in complex formation, CMN emitted fluorescence through inhibition of photoinduced electron transfer (PET). This probe exhibited excellent imaging ability for Fe3+, Al3+and Cr3+ ions in living cells with low cytotoxicity. Significantly, the cellular confocal microscopic research indicated that the lysosome-targeted group of morpholine moiety was introduced which realized the capability of imaging lysosomal trivalent metal ions in living cells for the first time.

5.
Radiat Res ; 191(6): 527-531, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30925136

RESUMO

Here we report on the interventions taken to treat a patient exposed to high-dose radiation and provide a protocol for treating such patients in the future. The patient, Mr. Wang, was a 58-year-old male janitor who was accidentally exposed to a 192Ir source with an activity of 966.4 GBq or 26.1 Ci. The dose estimated to the lower right limb was 4,100 Gy, whereas the whole-body effective dose was 1.51 Gy. The diagnosis was made according to the results of the patient dose estimation and clinical manifestations. Systemic treatment included stimulating bone marrow hematopoietic cells, enhancing immunity, anti-infection and vitamin supplements. The treatment of radiation-induced skin lesions consisted of several debridements, two skin-flap transplantations and application of mesenchymal stem cells (MSCs). Skin-flap transplantations and MSCs play important roles in the recovery of skin wound. A combination of antibiotics and antimycotic was useful in reducing inflammation. The application of vacuum sealing drainage was effective in removing necrotic tissue and bacteria, ameliorating ischemia and hypoxia of wound tissue, providing a fresh wound bed for wound healing and improving skin or flap graft survival rates. The victim survived the accident without amputation, and function of his highly exposed right leg was partially recovered. These results demonstrate the importance of collaboration among members of a multidisciplinary team in the treatment of this patient.

6.
Int J Mol Sci ; 18(3)2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-28300776

RESUMO

The lethal-7 (let-7) miRNA, known as one of the first founding miRNAs, is present in multiple copies in a genome and has diverse functions in animals. In this study, comparative genomic analysis of let-7 miRNAs members in fish species indicated that let-7 miRNA is a sequence conserved family in fish, while different species have the variable gene copy numbers. Among the ten members including let-7a/b/c/d/e/f/g/h/i/j, the let-7a precursor sequence was more similar to ancestral sequences, whereas other let-7 miRNA members were separate from the late differentiation of let-7a. The mostly predicted target genes of let-7 miRNAs are involved in biological process, especially developmental process and growth through Gene Ontology (GO) enrichment analysis. In order to identify the possible different functions of these ten miRNAs in fish growth development, their expression levels were quantified in adult males and females of Megalobrama amblycephala, as well as in 3-, 6-, and 12-months-old individuals with relatively slow- and fast-growth rates. These ten miRNAs had similar tissue expression patterns between males and females, with higher expression levels in the brain and pituitary than that in other tissues (p < 0.05). Among these miRNAs, the relative expression level of let-7a was the highest among almost all the tested tissues, followed by let-7b, let-7d and let-7c/e/f/g/h/i/j. As to the groups with different growth rates, the expression levels of let-7 miRNAs in pituitary and brain from the slow-growth group were always significantly higher than that in the fast-growth group (p < 0.05). These results suggest that let-7 miRNA members could play an important role in the regulation of growth development in M. amblycephala through negatively regulating expression of their target genes.


Assuntos
Cyprinidae/genética , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/genética , Animais , Tamanho Corporal , Encéfalo/metabolismo , Cyprinidae/crescimento & desenvolvimento , Feminino , Masculino , Hipófise/metabolismo
7.
Chemosphere ; 162: 1-7, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27474910

RESUMO

This work investigated the frequently observed "rebounds" of contaminants of concern in groundwater systems. Specifically, influences of bioaugmented microorganisms on the sorption and desorption of representative petroleum constituents [benzene, 1,3,5-trimethylbenzene and naphthalene (BTN)] were studied in freshly-spiked and historically-contaminated sediments. Capable microorganisms were enriched and supplemented to contaminated sediments to enhance biodegradation of petroleum hydrocarbons. In freshly-spiked sediments, when petroleum-degrading microorganisms were added, concentrations of dissolved petroleum constituents appeared to increase initially, and 12.4, 14.0 and 20.0 mg/kg of benzene, 1,3,5-trimethylbenzene and naphthalene, respectively desorbed from the sediments into the water phase. In the historically-contaminated sediments, the augmentation of petroleum-degrading microorganisms led to the desorption of 0.023-0.059, 0009-0.016, and 1.731-2.763 mg/L of previously sequestrated BTN into the water phase, and also triggered the desorption of 0.051-0.223, -0.133-2.630, and 2.324-1.200 mg/kg of previously sequestrated BTN as the methanol extraction quantity. The mechanisms of the enhanced desorption at the presence of microbes remain to be determined; however, we presumed that microbially produced constituents such as biosurfactants and cell mass could have attributed to the partition of petroleum compounds from the sediments. Findings from this study may partially explain "rebounds" of certain petroleum constituents into the groundwater during in situ bioremediation practice, although such immediate rebounds sometimes are weak, and the desorbed constituents can be eventually biodegraded under proper biogeochemical conditions.


Assuntos
Derivados de Benzeno/metabolismo , Naftalenos/metabolismo , Poluentes Químicos da Água/metabolismo , Absorção Fisico-Química , Benzeno/química , Benzeno/metabolismo , Derivados de Benzeno/química , Biodegradação Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos/metabolismo , Naftalenos/química , Petróleo/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
8.
Cell Biochem Biophys ; 71(1): 389-96, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25164111

RESUMO

The present study was conducted to explore the protective effect of exogenous gelsolin (GSN) in mice exposed to high-dose of radiation. Changes in the levels of GSNs in peripheral blood of mice and cytoplasm of cultured human intestinal epithelial cells (HIECs) were analyzed after their exposure to different doses of (137)Cs γ-rays at a fixed dose rate. The coagulation associated indices, such as prothrombin time (PT) and activated partial thromboplastin time (APTT) were measured. Effect on radiation-mediated oxidative damage was evaluated by estimating the altered glutathione (GSH) and malondialdehyde (MDA) concentrations in the blood. The results showed that radiation induced a pronounced decrease in the pGSN blood levels. However, the cGSN levels of irradiated HIECs were increased in a dose-dependent manner. Administration of recombinant human pGSN to irradiated mice resulted in an ameliorated clotting time as indicated by the PT and the APTT indices. The treatment of mice with hpGSN enhanced the blood levels of GSH while MDA concentrations were decreased indicating an improved antioxidant status. These results suggest that GSNs might play a regulatory role in the suppression of the tissue damage induced by acute radiation exposure.


Assuntos
Gelsolina/farmacologia , Lesões por Radiação/tratamento farmacológico , Animais , Coagulação Sanguínea/efeitos dos fármacos , Coagulação Sanguínea/efeitos da radiação , Catalase/sangue , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Relação Dose-Resposta à Radiação , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/efeitos da radiação , Raios gama/efeitos adversos , Gelsolina/sangue , Gelsolina/metabolismo , Gelsolina/uso terapêutico , Glutationa/sangue , Humanos , Intestinos/citologia , Masculino , Malondialdeído/sangue , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Lesões por Radiação/sangue , Lesões por Radiação/metabolismo , Lesões por Radiação/fisiopatologia , Superóxido Dismutase/metabolismo
9.
Biomed Environ Sci ; 26(12): 990-3, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24393509

RESUMO

To investigate the distribution of mitochondria DNA 4 977 bp deletion, a common deletion (CD), in normal populations of Chinese, human peripheral blood samples from sixty healthy donors were collected, and levels of the CD in genomic DNA from the samples were detected using real-time PCR. The results showed that the CD was found in 27 health donors, with its positive rate being 45% (27/60). The CD ratio was between 0 and 0.00308%, and not affected by age and gender in sixty healthy donors. Our studies indicate that the CD ratio is low, and do not show the age-dependent accumulation and any gender difference in peripheral whole blood from the normal Chinese population.


Assuntos
DNA Mitocondrial/genética , Deleção de Sequência , Sequência de Bases , Primers do DNA , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase em Tempo Real
10.
Bull Environ Contam Toxicol ; 86(6): 646-52, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21523506

RESUMO

The concentrations of uranium, thorium, barium, nickel, strontium and lead in the samples of the tailings and plant species collected from a uranium mill tailings repository in South China were analyzed. Then, the removal capability of a plant for a target element was assessed. It was found that Phragmites australis had the greatest removal capabilities for uranium (820 µg), thorium (103 µg) and lead (1,870 µg). Miscanthus floridulus had the greatest removal capabilities for barium (3,730 µg) and nickel (667 µg), and Parthenocissus quinquefolia had the greatest removal capability for strontium (3,920 µg). In this study, a novel coefficient, termed as phytoremediation factor (PF), was proposed, for the first time, to assess the potential of a plant to be used in phytoremediation of a target element contaminated soil. Phragmites australis has the highest PFs for uranium (16.6), thorium (8.68), barium (10.0) and lead (10.5). Miscanthus floridulus has the highest PF for Ni (25.0). Broussonetia papyrifera and Parthenocissus quinquefolia have the relatively high PFs for strontium (28.1 and 25.4, respectively). On the basis of the definition for a hyperaccumulator, only Cyperus iria and Parthenocissus quinquefolia satisfied the criteria for hyperaccumulator of uranium (36.4 µg/g) and strontium (190 µg/g), and could be the candidates for phytoremediation of uranium and strontium contaminated soils. The results show that the PF has advantage over the hyperaccumulator in reflecting the removal capabilities of a plant for a target element, and is more adequate for assessing the potential of a plant to be used in phytoremediation than conventional method.


Assuntos
Gleiquênias/metabolismo , Metais Pesados/metabolismo , Poaceae/metabolismo , Poluentes do Solo/metabolismo , Bário/análise , Bário/metabolismo , Biodegradação Ambiental , China , Chumbo/análise , Chumbo/metabolismo , Metalurgia , Metais Pesados/análise , Níquel/análise , Níquel/metabolismo , Poluentes do Solo/análise , Estrôncio/análise , Estrôncio/metabolismo , Tório/análise , Tório/metabolismo , Urânio/análise , Urânio/metabolismo
11.
Huan Jing Ke Xue ; 31(7): 1526-32, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20825021

RESUMO

Mixed plumes contained chlorinated solvents and petroleum hydrocarbons which mainly refers to BTEX (benzene, toluene, ethylbenzene and xylenes) in groundwater can be remediated by sequential units combined an iron permeable reactive barrier (Fe0-PRB) with an anoxic wall. In design of the Fe0-PRB it should be taken into account the necessity of altering the width of the iron cell in the presence of BTEX. Three column experiments were conducted to evaluate the effects of benzene, toluene on the long-term performance of reductive dechlorination of trichloroethylene (TCE) by granular iron. The results showed that the kinetics of TCE (at the initial concentration of 2 mg x L(-1) more or less) reduction was accorded with pseudo first-order even in the presence of benzene or toluene (at about 1-2 mg x L(-1), respectively). The existence of benzene and toluene inhibited the removal of TCE by 15.1% and 18. 5% , respectively; however, the presence of benzene slightly increased cis-1,2-DCE reduction rate by 4.5%, and the presence of toluene increased cis-1,2-DCE reduction rate by 42.8%. The inhibition of benzene and toluene other than mineral precipitates was not one of the decisive factors in the long-term performance of an Feo-PRB; in addition, the kinds of chlorinated daughter products of TCE in the presence/absence of benzene or toluene were identical and cis-1,2-dichloroethylene (cis-1,2-DCE), the major intermediate, firstly broke through from all the 3 columns at concentrations about 2-75 microg x L(-1), indicating that designing the width of an Fe0-PRB should be based on the hydraulic residence time of cis-1,2-DCE. In conclusion, if only considering the TCE remedial goals and disregarding the effects of cis-1,2-DCE on BTEX biodegradation downgradient the Fe0-PRB, the results suggested that it should be not necessary to increase the width of the iron cell for constructing sequential permeable reactive barriers (SPRBs) to rescue TCE- and BTEX-contaminated aquifers.


Assuntos
Benzeno/isolamento & purificação , Dicloroetilenos/química , Tolueno/isolamento & purificação , Tricloroetileno/química , Poluentes Químicos da Água/isolamento & purificação , Benzeno/química , Ferro/química , Oxirredução , Tolueno/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
12.
Bull Environ Contam Toxicol ; 83(4): 583-90, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19568683

RESUMO

The Huayuan River in Hunan Province in China is subject to ongoing mining activity with Mn extraction. In this study, the level and environmental significance of metals (including Mn, Cd, Pb, Cu, Zn, Ni and Fe) concentrations in the surface water and river sediments have been investigated along a 187 km reach of the Huayuan River. Using the X-ray fluorescence (XRF) analysis, we analyzed the characterization of metals in manganese sulphate waste residue (MSWR) deposited along the bank of Huayuan River. The speciation of metals in both sediment and MSWR was established using the BCR-three step sequential extraction procedure. In the water samples, the average concentrations of Mn, Cd and Pb exceeded the acceptable concentrations for drinking water in the WHO Guidelines for drinking water quality, Vol. 1, Recommendations, Geneva (2004) and Chinese (GB 5749-2006) guidelines, respectively. The average concentrations of Mn, Cd, Pb and Zn in the river sediments were found to be considerably higher than the corresponding world average shale values. The percentages of Cd (31.4%), Mn (31.1%), Zn (12.8%) and Pb (8.1%) associated with exchangeable and weak acid fraction in the sediments were higher than other metals. Mn (5.81%), Zn (0.208%), Pb (0.0292%) and Cd (0.0113%) were identified in MSWR by XRF analysis. The percentages of Mn, Cd, Zn and Pb associated with the exchangeable and weak acid soluble fraction in MSWR were 41.9%, 31.1%, 23.8% and 9.8%, respectively. The peak solute and sediment-bound metal concentrations were found at the sites of MSWR deposited along the bank of Huayuan River. The results suggested that MSWR deposited along the bank may have a closely relation with the metal pollution of Huayuan River. The results obtained may be useful to assess both short and long-term environmental impact of the MSWR deposited activities and support decisions for a future remediation of this river.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes da Água/análise , China , Sedimentos Geológicos/química , Rios , Abastecimento de Água/normas
13.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 25(2): 123-5, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15768874

RESUMO

OBJECTIVE: To evaluate the quality of clinical literatures related with treatment of lung cancer with combined use of chemotherapy and Chinese herbs in respect of the scientific research design adapted. METHODS: According to the "Scale for Quality and Information Evaluation of TCM Clinical Research Literature" formulated by the group of methodology of this article, the literatures related with lung cancer published between 1979 to 2000 were evaluated in respect of the randomization and controlling of the trial. RESULTS: The method of randomization was not described in 93.7% of the literatures; problems or mistakes of randomized allocation existed in 2.5%, with no record about the state of dropped out or absconded cases in follow-up study in 29.1%, also no record about case screening was found in all the literatures. Besides, the blind trial method was seldom used, also some problems of key links concerning samples homogeneity and conclusion reasoning presented. All these bugs could influence quality of the randomized control trial. CONCLUSION: Randomized control trial has been applied progressively in TCM clinical researches of lung cancer, however, there are still problems such as insufficiency of samples, and improving of the reliability and quality of the trial is needed.


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Fitoterapia , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Projetos de Pesquisa , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/uso terapêutico , Estudos de Avaliação como Assunto , Humanos
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(2): 129-31, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15768996

RESUMO

A series of high quality ZnWO4:Tm3+ single crystals were grown with Czochralski method. The concentrations of thulium ions were 0.1, 0.3, 0.5, 0.7 and 1.0 mol%, respectively. When ZnWO4:Tm3+ single crystals were excited by 807 nm laser, the up-conversion luminescence peaks at 486 and 695 nm which corresponded to transitions 1G4-->3H6 and 3F3-->3 H6, respectively, were detected. The intensity of 695 nm luminescence varied with the pump power in a double logarithmic relation whose indexes were 0.8 and 1.1 orders, respectively.


Assuntos
Lasers , Óxidos/química , Análise Espectral , Túlio/química , Tungstênio/química , Cristalização , Íons , Iluminação , Luminescência , Nanoestruturas , Fotoquímica , Análise Espectral Raman , Telúrio/química , Temperatura Ambiente , Difração de Raios X , Itérbio/química , Zinco/química
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