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1.
J Tradit Chin Med ; 44(1): 44-53, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213238

RESUMO

OBJECTIVE: To investigate the effect of Neferine (Nef) on diabetic nephropathy (DN) and to explore the mechanism of Nef in DN based on miRNA regulation theory. METHODS: A DN mouse model was constructed and treated with Nef. Serum creatinine (Crea), blood urea (UREA) and urinary albumin were measured in mice by kits, and renal histopathological changes and fibrosis were observed by hematoxylin-eosin staining and Masson staining. Renal tissue superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) activities were measured by enzyme-linked immunosorbent assay (ELISA). Western blotting was used to detect the expression of nuclear factor E2-related factor 2 (Nrf2)/ heme oxygenase 1 (HO-1) signaling pathway-related proteins in kidney tissues. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-17-5p in kidney tissues. Subsequently, a DN in vitro model was constructed by high glucose culture of human mesangial cells (HMCs), cells were transfected with miR-17-5p mimic and/or treated with Nef, and we used qRT-PCR to detect cellular miR-17 expression, flow cytometry to detect apoptosis, ELISAs to detect cellular SOD, MDA, and GSH-Px activities, Western blots to detect Nrf2/HO-1 signaling pathway-related protein expression, and dual luciferase reporter gene assays to verify the targeting relationship between Nrf2 and miR-17-5p. RESULTS: Administration of Nef significantly reduced the levels of blood glucose, Crea, and UREA and the expression of miR-17-5p, improved renal histopathology and fibrosis, significantly reduced MDA levels, elevated SOD and GSH-Px activities, and activated Nrf2 expression in kidney tissues from mice with DN. Nrf2 is a post-transcriptional target of miR-17-5p. In HMCs transfected with miR-17-5p mimics, the mRNA and protein levels of Nrf2 were significantly suppressed. Furthermore, miR-17-5p overexpression and Nef intervention resulted in a significant increase in high glucose-induced apoptosis and MDA levels in HMCs and a significant decrease in the protein expression of HO-1 and Nrf2. CONCLUSION: Collectively, these results indicate that Nef has an ameliorative effect on DN, and the mechanism may be through the miR-17-5p/Nrf2 pathway.


Assuntos
Benzilisoquinolinas , Diabetes Mellitus , Nefropatias Diabéticas , MicroRNAs , Humanos , Camundongos , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Antioxidantes/farmacologia , MicroRNAs/genética , Glucose , Fibrose , Superóxido Dismutase/metabolismo , Ureia/farmacologia , Estresse Oxidativo
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123272, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37607455

RESUMO

Erythromycin could be used to treat various bacterial infection, but it was harmful to the colonic microflora. Therefore, it is highly desirable to develop a fluorescence probe that could selectively and sensitively detect Erythromycin in pure water. In this work, a fluorescent probe named EHMC, which exhibited aggregation-induced emission (AIE) characteristic in solid state and water/EtOH binary solvent was developed for "turn on" sensing Erythromycin in pure water with high selectivity and sensitivity (detection limit: 1.78 × 10-8 M). Also, there are fewer interference from other antibiotics in the detection process of probe EHMC for Erythromycin. Moreover, probe EHMC could as a portable test strips for highly selective detection of Erythromycin and identification of different concentrations of Erythromycin. In addition, living cells imaging experiments displayed that probe EHMC could detect Erythromycin in A549 cells and BEAS-2B cells successfully. Combined with the theoretical calculation results The sensing mechanisms that the CO in Erythromycin and OH in EHMC formed intermolecular hydrogen bond and further formed new aggregates were confirmed by job' plot, 1H NMR, FT-IR, ESI-MS, DLS and TEM and DFT calculation.


Assuntos
Eritromicina , Água , Ligação de Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos
4.
ACS Omega ; 6(2): 1160-1170, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33490775

RESUMO

Chronic hepatitis B virus (CHB) infection is one of the primary risk factors associated with the development of hepatocellular carcinoma (HCC). Despite having been extensively studied, diagnosing early-stage HCC remains challenging, and diagnosed patients have a poor (3-5%) survival rate. Identifying new approaches to detect changes in the serum metabolic profiles of patients with CHB and liver cirrhosis (LC) may provide a valuable approach to better detect HCC at an early stage when it is still amenable to treatment, thereby improving patient prognosis and survival. In the present study, we, therefore, employed a liquid chromatography-mass spectrometry (LC-MS)-based approach to evaluate the serum metabolic profiles of 30 CHB patients, 29 LC patients, and 30 HCC patients. We then employed appropriate statistical methods to identify those metabolites that were best able to distinguish HCC cases from LC and CHB controls. A mass-based database was then used to putatively identify these metabolites. We then confirmed the identities of a subset of these metabolites through comparisons with the MS/MS fragmentation patterns and retention times of reference standards. The serum samples were then reanalyzed to quantify the levels of these selected metabolites and of other metabolites that have previously been identified as potential HCC biomarkers. Through this approach, we observed clear differences in the metabolite profiles of the CHB, LC, and HCC patient groups in both positive- and negative-ion modes. We found that the levels of taurodeoxy cholic acid (TCA) and 1,2-diacyl-3-ß-d-galactosyl-sn-glycerol rose with the progression from CHB to LC to HCC, whereas levels of 5-hydroxy-6E,8Z,11Z,14Z,17Z-eicosapentaenoic acid, and glycyrrhizic acid were gradually reduced with liver disease progression in these groups. The ROC analysis showed that taurodeoxy cholic acid (TCA), 1,2-diacyl-3-ß-d-galactosyl-sn-glycerol, 5-hydroxy-6E,8Z,11Z,14Z,17Z-eicosapentaenoic acid, and glycyrrhizic acid had a diagnosis performance with liver disease progression. These four metabolites have a significant correlation with alpha fetal protein (AFP) level and age. Our results highlight novel metabolic biomarkers that have the potential to be used for differentiating between CHB, LC, and HCC patients, thereby facilitating the identification and treatment of patients with early-stage HCC.

5.
J Dig Dis ; 19(9): 550-560, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30117288

RESUMO

OBJECTIVE: Palliative primary tumor resection (PTR) has been used for preventing and treating tumor-related complications. We aimed to determine whether PTR can increase overall survival (OS) in patients with unresectable metastatic colorectal cancer (CRC). METHODS: A retrospective review of a prospectively collected database in a single center was performed. Patients diagnosed with metastatic CRC from January 2004 to December 2014 were included. Patients who had attained curative resection or had disease recurrence were excluded. All patients were discussed at a multidisciplinary tumor board where subsequent treatment decisions were made. RESULTS: Altogether 408 patients were analyzed. Of these 145 received PTR with palliative chemotherapy (PC; group A), 110 received PC only (group B), 52 received PTR only (group C), while 101 received neither PTR nor PC (group D). Undergoing PTR led to statistically significant improvement in OS (22.7 months vs 12.1 months vs 6.9 months vs 2.7 months, P < 0.001). We performed subgroup analyses to control for potential confounders and found that the influence of PTR on OS persisted. With multivariate analysis, the predictors of poor OS were no PTR (hazards ratio [HR] 2.32, 95% confidence interval [CI] 1.82-2.96, P < 0.001), no PC (HR 4.25, 95% CI 3.27-5.33, P < 0.001) and the presence of peritoneal metastases (HR 1.37, 95% CI 1.06-1.78, P = 0.018). Diversion surgery did not lead to a statistical difference in OS. CONCLUSIONS: The absences of PTR and PC, and peritoneal metastases are independently associated with decreased OS in patients with unresectable metastatic CRC. Randomized controlled trials are needed to verify this observation.


Assuntos
Adenocarcinoma/secundário , Neoplasias Colorretais/cirurgia , Cuidados Paliativos/métodos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Colectomia/métodos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 53(8): 572-576, 2018 Aug 09.
Artigo em Chinês | MEDLINE | ID: mdl-30078275

RESUMO

Oral cavity is one of the main organs involved in chronic graft versus host disease (cGVHD). Oral cGVHD seriously affects the patient's quality of life. Topical use of glucocorticoid and other agents is the primary topical treatment of oral cGVHD, oral photochemical therapy and various new methods have also been applied in patients recently. These important adjuvant therapies are based on the systemic use of drugs such as immunosuppressive agents, and sometimes, may be the only effective treatment for oral cGVHD. This review will focus on the application of topical agent treatment and oral photochemotherapy in oral cGVHD patients.


Assuntos
Doença Enxerto-Hospedeiro/tratamento farmacológico , Doenças da Boca/tratamento farmacológico , Fotoquimioterapia/métodos , Administração Tópica , Adulto , Pesquisa Biomédica , Doença Crônica , Feminino , Glucocorticoides/administração & dosagem , Humanos , Imunossupressores/administração & dosagem , Masculino , Qualidade de Vida , Resultado do Tratamento
7.
Oral Dis ; 24(6): 964-971, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29498794

RESUMO

OBJECTIVES: To observe relationships between oral Candida status and salivary human beta-defensin 2 and 3 (hBD-2 and hBD-3) levels in HIV/AIDS patients of Guangxi, China during the first year of antiretroviral therapy (ART) dynamically, and to understand the influence of ART on oral Candida status and salivary hBDs expressions. METHODS: A prospective self-controlled study was carried to observe the dynamic changes of CD4+ T cell counts, oral Candida carriages and salivary hBD-2,3 expressions in HIV/AIDS patients during the first year of ART. A total of 90 HIV/AIDS patients were enrolled and were examined at the baseline, 3rd, 6th, 12th month of ART. Thirty healthy individuals were enrolled as control. Peripheral blood, oral rinse sample, and unstimulated whole saliva were collected to test CD4+ T cell counts, oral Candida carriages, and hBD-2,3 expressions. RESULTS: In the first year of ART, CD4+ T cell counts increased significantly. However, oral Candida carriages and oral candidiasis decreased significantly, and salivary hBD-2 expressions in HIV/AIDS patients decreased gradually, salivary hBD-3 levels were highly variable. Salivary hBD-2 concentrations were positively related to oral Candida carriages. CONCLUSIONS: The incidence of oral candidiasis among HIV/AIDS patients gradually decreased due to the immune reconstruction of ART. Salivary defensins might play an important role in Candida-host interaction in HIV/AIDS patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/metabolismo , Candidíase Bucal/metabolismo , Portador Sadio/metabolismo , Saliva/metabolismo , beta-Defensinas/metabolismo , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Adulto , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4 , Candidíase Bucal/microbiologia , Portador Sadio/microbiologia , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
8.
Arch Dermatol Res ; 309(4): 305-310, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28255674

RESUMO

Skin biopsies are a valuable technique in the diagnosis of cutaneous inflammatory and neoplastic conditions. We were interested to test the minimal size or equivalent volume by dilution of proteolytically disassociated skin tissue required to allow the isolation and propagation of cutaneous cells, for freezing, storage and biochemical analysis. It was possible to propagate with 100% efficiency fibroblast and melanocytic cells from a 0.1 to 0.5 mm3 equivalent neonatal foreskin sample using a combination of DispaseII and CollagenaseIV. The smallest tissue dilution that allowed melanocytic cell culture was 0.01 mm3, which equated to approximately 16 cells based on the average skin density of melanocytes. However, passaging of cells to create frozen stocks was achieved routinely only from 1 mm3 skin, equating to 1560 cells. Tissue-specific antigen expression of these cultures was tested by western blot of total protein extracts. There was no pigmentation antigen expression in fibroblast cultures; however, smooth muscle actin protein expression was high in fibroblast but absent from melanocytic cell strains. Melanocytic cells expressed pigmentation antigens and E-cadherin, but these were not detected in fibroblasts. Moreover, maturation of these melanocytic cells resulted in a decrease of Dopachrome Tautomerase antigen expression and induction of Tyrosinase protein consistent with the differentiation potential seen in cell cultures derived routinely from large sections of skin tissue.


Assuntos
Técnicas de Cultura de Células/métodos , Fibroblastos/fisiologia , Melanócitos/fisiologia , Pele/citologia , Caderinas/metabolismo , Diferenciação Celular , Células Cultivadas , Criopreservação , Humanos , Oxirredutases Intramoleculares/metabolismo , Miniaturização , Monofenol Mono-Oxigenase/metabolismo , Pele/metabolismo , Pigmentação da Pele
9.
BMC Med ; 15(1): 21, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28148249

RESUMO

BACKGROUND: Whether hypothyroidism is an independent risk factor for cardiovascular events is still disputed. We aimed to assess the association between hypothyroidism and risks of cardiovascular events and mortality. METHODS: We searched PubMed and Embase from inception to 29 February 2016. Cohort studies were included with no restriction of hypothyroid states. Priori main outcomes were ischemic heart disease (IHD), cardiac mortality, cardiovascular mortality, and all-cause mortality. RESULTS: Fifty-five cohort studies involving 1,898,314 participants were identified. Patients with hypothyroidism, compared with euthyroidism, experienced higher risks of IHD (relative risk (RR): 1.13; 95% confidence interval (CI): 1.01-1.26), myocardial infarction (MI) (RR: 1.15; 95% CI: 1.05-1.25), cardiac mortality (RR: 1.96; 95% CI: 1.38-2.80), and all-cause mortality (RR: 1.25; 95% CI: 1.13-1.39); subclinical hypothyroidism (SCH; especially with thyrotropin level ≥10 mIU/L) was also associated with higher risks of IHD and cardiac mortality. Moreover, cardiac patients with hypothyroidism, compared with those with euthyroidism, experienced higher risks of cardiac mortality (RR: 2.22; 95% CI: 1.28-3.83) and all-cause mortality (RR: 1.51; 95% CI: 1.26-1.81). CONCLUSIONS: Hypothyroidism is a risk factor for IHD and cardiac mortality. Hypothyroidism is associated with higher risks of cardiac mortality and all-cause mortality compared with euthyroidism in the general public or in patients with cardiac disease.


Assuntos
Doenças Cardiovasculares/epidemiologia , Hipotireoidismo/epidemiologia , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Humanos , Masculino , Fatores de Risco , Análise de Sobrevida
11.
Acta Biomater ; 33: 122-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26821341

RESUMO

Hydrogels with inherently conductive properties have been recently developed for tissue engineering applications, to serve as bioactive scaffolds to electrically stimulate cells and modulate their function. In this work, we have used interfacial polymerization of aniline monomers within gelatin methacrylate (GelMA) to develop a conductive hybrid composite. We demonstrate that as compared to pure GelMA, GelMA-polyaniline (GelMA-Pani) composite has similar swelling properties and compressive modulus, comparable cell adhesion and spreading responses, and superior electrical properties. Additionally, we demonstrate that GelMA-Pani composite can be printed in complex user-defined geometries using digital projection stereolithography, and will be useful in developing next-generation bioelectrical interfaces. STATEMENT OF SIGNIFICANCE: We report the fabrication of a conductive hydrogel using naturally-derived gelatin methyacrylate (GelMA) and inherently conductive polyaniline (Pani). This work is significant, as GelMA-Pani composite has superior electrical properties as compared to pure Gelma, all the while maintaining biomimetic physical and biocompatible properties. Moreover, the ability to fabricate conductive-GelMA in complex user-defined micro-geometries, address the significant processing challenges associated with all inherently conductive polymers including Pani. The methodology described in this work can be extended to several conductive polymers and hydrogels, to develop new biocompatible electrically active interfaces.


Assuntos
Compostos de Anilina/química , Condutividade Elétrica , Gelatina/química , Hidrogéis/química , Metacrilatos/química , Engenharia Tecidual/métodos , Compostos de Anilina/síntese química , Animais , Linhagem Celular , Espectroscopia Dielétrica , Impedância Elétrica , Gelatina/síntese química , Hidrogéis/síntese química , Teste de Materiais , Metacrilatos/síntese química , Camundongos , Impressão Tridimensional , Sus scrofa
13.
J Mater Chem B ; 3(26): 5352-5360, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32262611

RESUMO

Conducting hydrogels represent a new generation of "smart" biomaterials which combine the favorable biocompatibility properties of hydrogels and electrical properties of organic conductors, and would potentially lead to the development of new biointerfaces with controllable properties. Currently, conductive hydrogels are synthesized by either adding conducting particles to, or polymerizing conducting polymer monomers within, hydrogel matrix, however challenges in processing limit their applications in functional devices. In this work, a poly(ethylene glycol) diacrylate-polyaniline (PEGda-PANI) conductive hydrogel is developed using interfacial polymerization process. In this process, aniline monomers polymerize at the organic/water interface between hexane media and hydrophilic PEGda hydrogel networks. PANI chains become hydrophilic with acid doping and migrate into aqueous phase confined within PEGda networks. The synthesized PEGda-PANI hydrogel has acceptable mechanical, electrical and biocompatible properties. Traditional fabrication methods including process-driven salt-leaching and design-driven projection stereolithography were used to develop 3D scaffolds using PEGda-PANI hydrogels. This methodology can be potentially extended to a wide variety of fabrication techniques to develop hydrogels with complex geometries and next-generation functional biointerfaces.

14.
J Periodontal Res ; 50(3): 403-10, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25065393

RESUMO

BACKGROUND AND OBJECTIVE: Periodontal diseases are often induced by periodontopathogens, which are always exposed to certain innate immune factors in gingival crevicular fluid, including human ß-defensin-2 (hBD-2). This study aims to investigate the relationship among periodontopathogens, clinical parameters and hBD-2 expression. MATERIAL AND METHODS: Thirty-two healthy controls, 42 patients with chronic gingivitis and 95 patients with chronic periodontitis were recruited in Guangxi, China. Bleeding index, probing depth and clinical attachment level were measured for all teeth including mesiobuccal, buccal, disobuccal, mesiolingual, lingual, disolingual six sites of all patient. Gingival crevicular fluid samples were collected from the study sites. The prevalence and copy numbers (CN) of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, Tannerella forsythia and total bacteria in gingival crevicular fluid were quantified by real-time PCR. The hBD-2 concentration in gingival crevicular fluid was measured by ELISA. RESULTS: Both the prevalence and the CN of A. actinomycetemcomitans, P. gingivalis, T. denticola and T. forsythia were higher in patients with chronic periodontitis than in healthy controls and patients with chronic gingivitis; however, there was no significant difference in the prevalence of P. intermedia among the three study groups, and the highest CN was found in patients with chronic gingivitis, rather than in patients with chronic periodontitis. The loads of P. gingivalis, P. intermedia, T. denticola and total bacteria were positively related to probing depth, bleeding index and clinical attachment level. The concentration of hBD-2 in gingival crevicular fluid was higher in patients with chronic gingivitis and in patients with chronic periodontitis than in healthy controls. In addition, the hBD-2 concentration was positively related to the CN of P. gingivalis, T. forsythia and total bacteria, as well as to bleeding index and probing depth. CONCLUSION: The prevalence, composition and CN of periodontopathogens were closely related to the severity of periodontal disease, and the red complex was related to the severity of clinical symptoms of periodontal diseases. The concentration of hBD-2 in gingival crevicular fluid from periodontal disease sites was higher than that in gingival crevicular fluid from healthy sites, which suggests that hBD-2 expression might be up-regulated by periodontopathogens.


Assuntos
Periodontite Crônica/microbiologia , Líquido do Sulco Gengival/microbiologia , Gengivite/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , beta-Defensinas/análise , Adulto , Aggregatibacter actinomycetemcomitans/isolamento & purificação , Carga Bacteriana , Bacteroides/imunologia , Bacteroides/isolamento & purificação , Periodontite Crônica/imunologia , Feminino , Líquido do Sulco Gengival/imunologia , Gengivite/imunologia , Bactérias Gram-Negativas/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/imunologia , Perda da Inserção Periodontal/microbiologia , Índice Periodontal , Bolsa Periodontal/imunologia , Bolsa Periodontal/microbiologia , Porphyromonas gingivalis/imunologia , Porphyromonas gingivalis/isolamento & purificação , Prevotella intermedia/isolamento & purificação , Treponema denticola/isolamento & purificação , Adulto Jovem
15.
J Environ Sci Health B ; 49(10): 738-46, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25065825

RESUMO

The enantioselective environmental behavior of the chiral fungicides benalaxy and furalaxyl in agricultural soils in China was studied. Although sorption onto soils was non-enantioselective, the leaching of benalaxy and furalaxyl was enantioselective in soil columns. The concentrations of the S-enantiomers of both fungicides in the leachates were higher than the R-enantiomers. This can be attributed to enantioselective degradation of the two fungicides in the soil column. Enantioselective degradation of the two fungicides was verified by soil dissipation experiments, and the R-enantiomers degraded faster than the S-enantiomers in partial soils. The half-life was 27.7-57.8 days for S-benalaxyl, 20.4-53.3 days for R-benalaxyl, 19.3-49.5 days for S-furalaxyl and 11.4-34.7 days for R-furalaxyl. The degradation process of the two fungicide enantiomers followed the first-order kinetics (R(2) > 0.96). Compared to furalaxyl, benalaxyl degraded more slowly and degradation was less enantioselective. These results are attributed to the influence of soil physicochemical properties, soil microorganisms, and environmental factors.


Assuntos
Agricultura , Alanina/análogos & derivados , Fungicidas Industriais/química , Furanos/química , Poluentes do Solo/química , Solo/química , Absorção Fisico-Química , Adsorção , Alanina/química , Biodegradação Ambiental , China , Meia-Vida , Cinética , Estereoisomerismo
16.
Lett Appl Microbiol ; 58(3): 255-61, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24236847

RESUMO

UNLABELLED: Phytochelatins (PCs) are cysteine-rich peptides with high binding affinity for toxic metals. Expressing the PC synthase gene (PCS) in plant growth-promoting bacteria may enhance its metal resistance and accumulation, consequently increasing phytoremediation efficiency in heavy metal pollution. In this study, PCS from Schizosaccharomyces pombe was cloned and expressed in Pseudomonas putida KT2440, which was confirmed by real-time RT-PCR through an increase in SpPCS mRNA expression level when induced by 20 µmol of CdCl2 in the transformed Ps. putida cells. The recombined strain KT2440-SpPCS exhibited enhanced Cd, Ag and Hg resistance. Compared with the original strain, KT2440-SpPCS also displayed a threefold to fivefold increase in Cd accumulation (14·32 µmol g(-1) to 17·38 µmol g(-1) ; dry weight) when grown in 30 and 50 µmol CdCl2 , along with an increase in nonprotein thiols. Further experiments showed significantly enhanced germination rates and growth of wheat seeds in 0·1 mmol to 1·0 mmol Cd when inoculated with KT2440-SpPCS. This study shows potential use of Ps. putida KT2440-SpPCS in plants to construct a symbiotic system for an enhanced phytoremediation of heavy metal-contaminated environments. SIGNIFICANCE AND IMPACT OF THE STUDY: The symbiotic system of using plant growth-promoting bacteria Pseudomonas putida to express phytochelatin synthase gene of Schizosaccharomyces pombe together in plants resulted in high heavy metal resistance and high accumulation capacity, suggesting potential enhancement in phytoremediation of heavy metal-contaminated environments.


Assuntos
Aminoaciltransferases/genética , Cádmio/metabolismo , Proteínas Fúngicas/genética , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , Schizosaccharomyces/genética , Aminoaciltransferases/metabolismo , Proteínas Fúngicas/metabolismo , Expressão Gênica , Metais Pesados/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/microbiologia , Triticum/crescimento & desenvolvimento , Triticum/microbiologia
18.
Micron ; 43(7): 782-817, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22417678

RESUMO

This paper provides an overview on structural assessment of nanocomposite materials. First of all, a brief description of advanced structure characterization methods such as scanning electron microscopy, X-ray diffraction, transmission electron microscopy, atomic force microscopy, and scanning tunneling microscopy is presented. Secondly, applications of these methods for analysis of structures and compositions of typical nanocomposites are introduced. The nanocomposites are formed by different nanoscale processing technologies. Electrochemically polymerized polyaniline (PANi) nanocomposites, thermomechanically processed metal matrix nanocomposites, nanocast ceramic matrix composites are typical examples discussed in this paper. Case studies on several functional nanocomposites for energy storage/conversion, catalysis and sensing applications are mentioned. After that, assessment of the interface structures of nanocomposite materials using surface characterization techniques and mechanical damage models is discussed. Finally, concluding remarks are provided.

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