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1.
Hortic Res ; 9: uhac216, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36479586

RESUMO

Cinnamomum species attract attentions owing to their scents, medicinal properties, and ambiguous relationship in the phylogenetic tree. Here, we report a high-quality genome assembly of Cinnamomum camphora, based on which two whole-genome duplication (WGD) events were detected in the C. camphora genome: one was shared with Magnoliales, and the other was unique to Lauraceae. Phylogenetic analyses illustrated that Lauraceae species formed a compact sister clade to the eudicots. We then performed whole-genome resequencing on 24 Cinnamomum species native to China, and the results showed that the topology of Cinnamomum species was not entirely consistent with morphological classification. The rise and molecular basis of chemodiversity in Cinnamomum were also fascinating issues. In this study, six chemotypes were classified and six main terpenoids were identified as major contributors of chemodiversity in C. camphora by the principal component analysis. Through in vitro assays and subcellular localization analyses, we identified two key terpene synthase (TPS) genes (CcTPS16 and CcTPS54), the products of which were characterized to catalyze the biosynthesis of two uppermost volatiles (i.e. 1,8-cineole and (iso)nerolidol), respectively, and meditate the generation of two chemotypes by transcriptional regulation and compartmentalization. Additionally, the pathway of medium-chain triglyceride (MCT) biosynthesis in Lauraceae was investigated for the first time. Synteny analysis suggested that the divergent synthesis of MCT and long-chain triglyceride (LCT) in Lauraceae kernels was probably controlled by specific medium-chain fatty acyl-ACP thioesterase (FatB), type-B lysophosphatidic acid acyltransferase (type-B LPAAT), and diacylglycerol acyltransferase 2b (DGAT 2b) isoforms during co-evolution with retentions or deletions in the genome.

2.
Theranostics ; 10(24): 11110-11126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042273

RESUMO

Rationale: Many external factors can induce the melanogenesis and inflammation of the skin. Salidroside (SAL) is the main active ingredient of Rhodiola, which is a perennial grass plant of the Family Crassulaceae. This study evaluated the effect and molecular mechanism of SAL on skin inflammation and melanin production. It then explored the molecular mechanism of melanin production under ultraviolet (UV) and inflammatory stimulation. Methods: VISIA skin analysis imaging system and DermaLab instruments were used to detect the melanin reduction and skin brightness improvement rate of the volunteers. UV-treated Kunming mice were used to detect the effect of SAL on skin inflammation and melanin production. Molecular docking and Biacore were used to verify the target of SAL. Immunofluorescence, luciferase reporter assay, CO-IP, pull-down, Western blot, proximity ligation assay (PLA), and qPCR were used to investigate the molecular mechanism by which SAL regulates skin inflammation and melanin production. Results: SAL can inhibit the inflammation and melanin production of the volunteers. SAL also exerted a protective effect on the UV-treated Kunming mice. SAL can inhibit the tyrosinase (TYR) activity and TYR mRNA expression in A375 cells. SAL can also regulate the ubiquitination degradation of interferon regulatory factor 1 (IRF1) by targeting prolyl 4-hydroxylase beta polypeptide (P4HB) to mediate inflammation and melanin production. This study also revealed that IRF1 and upstream stimulatory factor 1 (USF1) can form a transcription complex to regulate TYR mRNA expression. IRF1 also mediated inflammatory reaction and TYR expression under UV- and lipopolysaccharide-induced conditions. Moreover, SAL derivative SAL-plus (1-(3,5-dihydroxyphenyl) ethyl-ß-d-glucoside) showed better effect on inflammation and melanin production than SAL. Conclusion: SAL can inhibit the inflammation and melanogenesis of the skin by targeting P4HB and regulating the formation of the IRF1/USF1 transcription complex. In addition, SAL-plus may be a new melanin production and inflammatory inhibitor.


Assuntos
Glucosídeos/farmacologia , Hiperpigmentação/tratamento farmacológico , Melaninas/metabolismo , Fenóis/farmacologia , Preparações Clareadoras de Pele/farmacologia , Pigmentação da Pele/efeitos dos fármacos , Adulto , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Glucosídeos/uso terapêutico , Voluntários Saudáveis , Humanos , Hiperpigmentação/imunologia , Hiperpigmentação/patologia , Fator Regulador 1 de Interferon/metabolismo , Masculino , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/efeitos da radiação , Camundongos , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Fenóis/uso terapêutico , Pró-Colágeno-Prolina Dioxigenase/antagonistas & inibidores , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Isomerases de Dissulfetos de Proteínas/antagonistas & inibidores , Isomerases de Dissulfetos de Proteínas/metabolismo , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/imunologia , Envelhecimento da Pele/efeitos da radiação , Creme para a Pele/farmacologia , Creme para a Pele/uso terapêutico , Preparações Clareadoras de Pele/uso terapêutico , Pigmentação da Pele/efeitos da radiação , Ativação Transcricional/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Fatores Estimuladores Upstream/metabolismo , Adulto Jovem
3.
Phytother Res ; 30(4): 663-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26833708

RESUMO

Acute pancreatitis is an inflammatory process originated in the pancreas; however, it often leads to systemic complications that affect distant organs. Acute respiratory distress syndrome is indeed the predominant cause of death in patients with severe acute pancreatitis. In this study, we aimed to delineate the ameliorative effect of dihydro-resveratrol, a prominent analog of trans-resveratrol, against acute pancreatitis-associated lung injury and the underlying molecular actions. Acute pancreatitis was induced in rats with repetitive injections of cerulein (50 µg/kg/h) and a shot of lipopolysaccharide (7.5 mg/kg). By means of histological examination and biochemical assays, the severity of lung injury was assessed in the aspects of tissue damages, myeloperoxidase activity, and levels of pro-inflammatory cytokines. When treated with dihydro-resveratrol, pulmonary architectural distortion, hemorrhage, interstitial edema, and alveolar thickening were significantly reduced in rats with acute pancreatitis. In addition, the production of pro-inflammatory cytokines and the activity of myeloperoxidase in pulmonary tissues were notably repressed. Importantly, nuclear factor-kappaB (NF-κB) activation was attenuated. This study is the first to report the oral administration of dihydro-resveratrol ameliorated acute pancreatitis-associated lung injury via an inhibitory modulation of pro-inflammatory response, which was associated with a suppression of the NF-κB signaling pathway.


Assuntos
Pneumopatias/tratamento farmacológico , Pulmão/efeitos dos fármacos , Pancreatite/tratamento farmacológico , Estilbenos/farmacologia , Animais , Ceruletídeo/efeitos adversos , Citocinas/metabolismo , Pulmão/patologia , Pneumopatias/complicações , NF-kappa B/metabolismo , Pâncreas/efeitos dos fármacos , Pancreatite/induzido quimicamente , Pancreatite/complicações , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Resveratrol , Transdução de Sinais/efeitos dos fármacos , alfa-Amilases/sangue
4.
Clin Chem Lab Med ; 54(2): 345-51, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26351925

RESUMO

BACKGROUND: The aim of this study was to determine whether neutrophil CD64 (nCD64) combined with procalcitonin (PCT), C-reactive protein (CRP) and white blood cell count (WBC) can increase the sensitivity and accuracy of neonatal sepsis diagnosis. METHODS: The serum levels of nCD64, CRP, PCT and WBC were detected in 60 patients with neonatal sepsis and 60 patients with non-sepsis. Sensitivity, specificity, positive and negative predictive values, receiver operating characteristic (ROC) area under the curve (AUC), and logistic regression analysis were performed to evaluate the diagnostic value of these markers on neonatal sepsis. RESULTS: Serum levels of nCD64, PCT, CRP and WBC were higher in the sepsis group than non-sepsis group (p<0.001). The sensitivities of nCD64, PCT, CRP and WBC at the recommended cut-off level for all infants were 79.5%, 68.2%, 38.6% and 52.3%, respectively. The best combination was nCD64 and PCT, which obtained sensitivity of 90.9%, largest AUC of 0.922, and a negative predictive value of 89.2%. However by using an optimal cut-off value, the sensitivities of all four biomarkers for the diagnosis of neonatal sepsis were increased to 95.5%. Except for WBC, the birth weight and gestational age had no effects on the diagnostic value of these serum biomarkers. CONCLUSIONS: nCD64 and PCT are better diagnostic biomarkers for early diagnosis of neonatal sepsis as compared to CRP. With the help of optimal cut-off value based on ROC curve and logistic regression analysis, the combination of these biomarkers could improve the sensitivity for the diagnosis of suspected late-onset neonatal sepsis based on common serum biomarkers.


Assuntos
Proteína C-Reativa/análise , Calcitonina/sangue , Neutrófilos/metabolismo , Precursores de Proteínas/sangue , Receptores de IgG/sangue , Sepse/diagnóstico , Área Sob a Curva , Biomarcadores/sangue , Peso ao Nascer , Peptídeo Relacionado com Gene de Calcitonina , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Contagem de Leucócitos , Modelos Logísticos , Masculino , Razão de Chances , Curva ROC , Estudos Retrospectivos , Sepse/sangue
5.
Talanta ; 139: 226-32, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25882430

RESUMO

In this study, a simple and sensitive aptamer-based fluorescence method for the detection of Kanamycin A by using gold nanoparticles (AuNPs) has been developed. In this assay, AuNPs were utilized as DNA nanocarrier as well as efficient fluorescence quencher. In the absence of Kanamycin A, dye-labeled aptamer could be adsorbed onto the surface of AuNPs and the fluorescence signal was quenched. In the presence of Kanamycin A, the specific binding between dye-labeled aptamer and its target induced the formation of rigid structure, which led to dye-labeled aptamer releasing from the surface of AuNPs and the fluorescence intensity was recovered consequently. Under optimum conditions, calibration modeling showed that the analytical linear range covered from 0.8nM to 350nM and the detection limit of 0.3nM was realized successfully. This proposed bio-assay also showed high selectivity over other antibiotics. Meanwhile, this strategy was further used to determine the concentrations of Kanamycin A in milk sample with satisfying results.


Assuntos
Aptâmeros de Nucleotídeos/química , Bioensaio/métodos , Técnicas Biossensoriais/métodos , Ouro/química , Canamicina/análise , Nanopartículas Metálicas/química , Fluorescência , Limite de Detecção , Sensibilidade e Especificidade , Razão Sinal-Ruído
6.
Environ Sci Pollut Res Int ; 22(9): 6660-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25414034

RESUMO

The pseudosolubilized medium-chain-length n-alkanes during biodegradation process, and optimization of medium composition and culture conditions for rhamnolipid production by Pseudomonas sp. DG17 using Plackett-Burman design and Box-Behnken design, were examined in this study. The results showed that pseudosolubilized concentration of C14 to C20 n-alkanes was higher than that of C24 to C26. After incubation for 120 h, pseudosolubilized C16H34 increased to 2.63 ± 0.21 mg. Meanwhile, biodegradation rates of n-alkanes decreased along with the increase of carbon chain length. Carbon-14 assay suggested that nonlabeled C14H30, C16H34, and C20H42 inhibited the biodegradation of (14)C n-octadecane, and Pseudomonas sp. DG17 utilized different alkanes simultaneously. Three significant variables (substrate concentration, salinity, and C/N) that could influence rhamnolipid production were screened by Plackett-Burman design. Results of Box-Behnken design suggested that rhamnolipid concentration could be achieved at 91.24 mg L(-1) (observed value) or 87.92 mg L(-1) (predicted value) with the optimal levels of concentration, salinity, and C/N of 400 mg L(-1), 1.5 %, and 45, respectively.


Assuntos
Alcanos/metabolismo , Glicolipídeos/metabolismo , Pseudomonas/metabolismo , Tensoativos/metabolismo , Biodegradação Ambiental , Radioisótopos de Carbono , Petróleo/metabolismo , Poluição por Petróleo/prevenção & controle , Poluentes do Solo/metabolismo , Solubilidade
7.
Biotechnol Biotechnol Equip ; 28(5): 834-842, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26019567

RESUMO

A strain of Pseudomonas sp. DG17, capable of degrading crude oil, was immobilized in sodium alginate-attapulgite-calcium carbonate for biodegradation of crude oil contaminated soil. In this work, proportion of independent variables, the laboratory immobilization parameters, the micromorphology and internal structure of the immobilized granule, as well as the crude oil biodegradation by sodium alginate-attapulgite-calcium carbonate immobilized cells and sodium alginate-attapulgite immobilized cells were studied to build the optimal immobilization carrier and granule-forming method. The results showed that the optimal concentrations of sodium alginate-attapulgite-calcium carbonate and calcium chloride were 2.5%-3.5%, 0.5%-1%, 3%-7% and 2%-4%, respectively. Meanwhile, the optimal bath temperature, embedding cell amount, reaction time and multiplication time were 50-60 °C, 2%, 18 h and 48 h, respectively. Moreover, biodegradation was enhanced by immobilized cells with a total petroleum hydrocarbon removal ranging from 33.56% ± 3.84% to 56.82% ± 3.26% after 20 days. The SEM results indicated that adding calcium carbonate was helpful to form internal honeycomb-like pores in the immobilized granules.

8.
Biotechnol Biotechnol Equip ; 28(2): 165-175, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26740752

RESUMO

Petroleum-based products are a primary energy source in the industry and daily life. During the exploration, processing, transport and storage of petroleum and petroleum products, water or soil pollution occurs regularly. Biodegradation of the hydrocarbon pollutants by indigenous microorganisms is one of the primary mechanisms of removal of petroleum compounds from the environment. However, the physical contact between microorganisms and hydrophobic hydrocarbons limits the biodegradation rate. This paper presents an updated review of the petroleum hydrocarbon uptake and transport across the outer membrane of microorganisms with the help of outer membrane proteins.

9.
Biotechnol Biotechnol Equip ; 28(3): 463-470, 2014 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-26740764

RESUMO

In soil bioremediation techniques, the trans-membrane transport of hydrocarbons across the cell membrane is a new and complex point of understanding the process of hydrocarbons biodegradation. In this study, the effect of different environmental factors, including substrate concentration, bacterial inoculums, pH, salinity, substrate analogues and nutrients, on the transport of [14C]n-octadecane by Pseudomonas sp. DG17 was investigated. The results showed that cellular [14C]n-octadecane levels increased along with the increase in the substrate concentration. However, the trans-membrane transport of [14C]n-octadecane was a saturable process in the case of equal amounts of inoculum (biomass). The highest concentration of accumulated [14C]n-octadecane was 0.51 µmol mg-1 ± 0.028 µmol mg-1 after incubation for 20 min. Meanwhile, the cellular n-octadecane concentration decreased along with the biomass increase, and reached a stable level. Acidic/alkaline conditions, high salinity, and supplement of substrate analogues could inhibit the transport of [14C]n-octadecane by Pseudomonas sp. DG17, whereas nitrogen or phosphorus deficiency did not influence this transport. The results suggested that trans-membrane transport of octadecane depends on both the substrate concentration and the microorganism biomass, and extreme environmental conditions could influence the biodegradation ability of microorganisms through inhibiting the transport of extracellular octadecane.

10.
Zhonghua Yi Shi Za Zhi ; 43(3): 157-63, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-24060029

RESUMO

There were the records of heart failure in the 6(th) century B.C. At that time, clinical observation was the main approach. The combination of observation and anatomy in the 18(th) century rendered the application of pathological anatomy in the research of etiology and pathogenesis of heart failure possible. Up to the 19(th) century, with the upsurge of modern science, the laboratory became the center of medicine. The introduction of experiment into the clinic was used in the exploration of clinical significance of changes of the diseased heart's size and shape, and the difference between cardiac hypertrophy and cardiectasis was found. The pathogenesis of these two diseases was analyzed, and the significance of compensation in cardiac hypertrophy was revealed, then the relationship of cardiovalvular disease, cardiac hypertrophy and cardiac dilatation was demonstrated.

11.
J Microbiol ; 51(6): 791-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24385357

RESUMO

The trans-membrane transport of hydrocarbons is an important and complex aspect of the process of biodegradation of hydrocarbons by microorganisms. The mechanism of transport of (14)C n-octadecane by Pseudomonas sp. DG17, an alkane-degrading bacterium, was studied by the addition of ATP inhibitors and different substrate concentrations. When the concentration of n-octadecane was higher than 4.54 µmol/L, the transport of (14)C n-octadecane was driven by a facilitated passive mechanism following the intra/extra substrate concentration gradient. However, when the cells were grown with a low concentration of the substrate, the cellular accumulation of n-octadecane, an energy-dependent process, was dramatically decreased by the presence of ATP inhibitors, and n-octadecane accumulation continually increased against its concentration gradient. Furthermore, the presence of non-labeled alkanes blocked (14)C n-octadecane transport only in the induced cells, and the trans-membrane transport of n-octadecane was specific with an apparent dissociation constant K t of 11.27 µmol/L and V max of 0.96 µmol/min/mg protein. The results indicated that the trans-membrane transport of n-octadecane by Pseudomonas sp. DG17 was related to the substrate concentration and ATP.


Assuntos
Alcanos/metabolismo , Membrana Celular/metabolismo , Pseudomonas/metabolismo , Trifosfato de Adenosina/metabolismo , Alcanos/química , Biodegradação Ambiental , Transporte Biológico , Membrana Celular/química , Hidrocarbonetos/metabolismo , Cinética , Pseudomonas/química
12.
Zhonghua Yi Shi Za Zhi ; 42(2): 89-99, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22782028

RESUMO

In 1905, Carrel and Guthrie reported the heterotopic heart transplantation on dogs for the first time. In the same year, Shone advanced the transplantation immunity theory which provided a basis for organ transplantation. In 1964, Hardy and his colleagues performed the first human chimpanzee heart transplantation. In 1967, Barnard performed the first human-to-human orthotopic heart transplantation in the world. In 1968 - 1971, 56 hospitals performed 180 heart transplantations world-wide. But because of the poor survival rate after operation, heart transplantations became less frequent. In 1972, Castaneda and Reitz summed up the experiences of heart-lung experimental transplantation, which laid a foundation for human heart-lung transplantation. In 1973, Caves invented myocardium biopsy for rejection surveillance after heart transplantation, which solved the problem of diagnosis for early rejection. In 1981, Stanford University first took cyclosporin A into clinical practice. The acute rejection after heart transplantation was effectively controlled and the long-term survival rate was significantly increased. Heart transplantation entered the second peak period. The launching of Asian heart transplantation began in 1968. Juro·Wada with his medical team performed the first heart transplantation in Japan. In 1978, Zhang Shize in Shanghai performed the first heart transplantation in China.

13.
Anal Chim Acta ; 710: 111-7, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22123119

RESUMO

Genotyping of cytochrome P450 monooxygenase 2D6*10 (CYP2D6*10) plays an important role in pharmacogenomics, especially in clinical drug therapy of Asian populations. This work reported a novel label-free technique for genotyping of CYP2D6*10 based on ligation-mediated strand displacement amplification (SDA) with DNAzyme-based chemiluminescence detection. Discrimination of single-base mismatch is firstly accomplished using DNA ligase to generate a ligation product. The ligated product then initiates a SDA reaction to produce aptamer sequences against hemin, which can be probed by chemiluminescence detection. The proposed strategy is used for the assay of CYP2D6*10 target and the genomic DNA. The results reveal that the proposed technique displays chemiluminescence responses in linear correlation to the concentrations of DNA target within the range from 1 pM to 1 nM. A detection limit of 0.1 pM and a signal-to-background ratio of 57 are achieved. Besides such high sensitivity, the proposed CYP2D6*10 genotyping strategy also offers superb selectivity, great robustness, low cost and simplified operations due to its label-free, homogeneous, and chemiluminescence-based detection format. These advantages suggest this technique may hold considerable potential for clinical CYP2D6*10 genotyping and association studies.


Assuntos
Citocromo P-450 CYP2D6/genética , DNA Catalítico/metabolismo , Medições Luminescentes , Técnicas de Amplificação de Ácido Nucleico , Aptâmeros de Nucleotídeos/química , Pareamento Incorreto de Bases , DNA Ligase Dependente de ATP , DNA Ligases/metabolismo , Genótipo , Hemina/química , Polimorfismo de Nucleotídeo Único
14.
Nucleic Acids Res ; 39(18): e122, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21742759

RESUMO

Development of novel aptamer sensor strategies for rapid and selective assays of protein biomarkers plays crucial roles in proteomics and clinical diagnostics. Herein, we have developed a novel aptamer sensor strategy for homogeneous detection of protein targets based on fluorescence protection assay. This strategy is based on our reasoning that interaction of aptamer with its protein target may dramatically increase steric hindrance, which protects the fluorophore, fluorescein isothiocyannate (FITC), labeled at the binding pocket from accessing and quenching by the FITC antibody. The aptamer sensor strategy is demonstrated using a model protein target of immunoglobulin E (IgE), a known biomarker associated with atopic allergic diseases. The results reveal that the aptamer sensor shows substantial (>6-fold) fluorescence enhancement in response to the protein target, thereby verifying the mechanism of fluorescence protection. Moreover, the aptamer sensor displays improved specificity to other co-existing proteins and a desirable dynamic range within the IgE concentration from 0.1 to 50 nM with a readily achieved detection limit of 0.1 nM. Because of great robustness, easy operation and scalability for parallel assays, the developed homogeneous fluorescence protection assay strategy might create a new methodology for developing aptamer sensors in sensitive, selective detection of proteins.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Fluorometria/métodos , Proteínas/análise , Corantes Fluorescentes , Imunoglobulina E/análise
15.
Huan Jing Ke Xue ; 32(3): 886-95, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21634193

RESUMO

Seed germination, root elongation, shoot elongation and ratio of shoot to root of wheat in soils polluted by lead (Pb) and benzo (a)pyrene (B[a] P) with medium-low concentrations were studied to reveal the ecological effects of combined pollution and screen the indicative markers. Results indicated that seed germination was not sensitive to single or combined pollution of Pb or B[a] P. Root elongation was inhibited by single pollution of Pb or B[a]P to different extents. Extensive interactions between Pb and B[a]P occurred to root elongation of wheat, including synergistic-stimulatory effect and antagonistic-inhibitory effect. The joint action was mainly antagonistic. Single pollution of B [a] P had an inhibitory effect on shoot elongation. Under combined pollution conditions, the shoot elongation of wheat correlated well with Pb contents (p < 0.01). B[a] P or the interactions between pollutants had little effect on shoot elongation of wheat. The joint action on shoot elongation was consistently antagonistic. The response pattern of the ratio of shoot to root was similar to the response pattern of shoot elongation. However, the former had better correlation than the latter, indicating it as a more suitable indicative marker for Pb pollution. If lead acetate was employed instead of lead nitrate, longer root elongation, shorter shoot elongation and no effect on ratio of shoot to root were found. Therefore, the forms of Pb salt had significant influence on seed growth of wheat in soils.


Assuntos
Benzo(a)pireno/toxicidade , Chumbo/toxicidade , Sementes/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Triticum/crescimento & desenvolvimento , Benzo(a)pireno/análise , Sinergismo Farmacológico , Germinação/efeitos dos fármacos , Chumbo/análise , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Poluentes do Solo/análise , Triticum/efeitos dos fármacos
16.
Anal Chem ; 83(6): 1883-9, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21348511

RESUMO

Genotyping of single nucleotide polymorphisms (SNPs) is a central challenge in disease diagnostics and personalized medicine. A novel label-free homogeneous SNP genotyping technique is developed on the basis of ligation-mediated strand displacement amplification (SDA) with DNAzyme-based chemiluminescence detection. Discrimination of single-base mismatches is first accomplished using DNA ligase to generate a ligation product between a discriminant probe and a common probe. The ligated product then initiates two consecutive SDA reactions to produce a great abundance of aptamer sequences against hemin, which can be probed by chemiluminscence detection. The developed strategy is demonstrated using a model SNP target of cytochrome P450 monooxygenase CYP2C19*2, a molecular marker for personalized medicines. The results reveal that the developed technique displays superb selectivity in discriminating single-base mismatches, very low detection limit as low as 0.1 fM, a wide dynamic range from 1 fM to 1 nM, and a high signal-to-background ratio of 150. Due to its label-free, homogeneous, and chemiluminescence-based detection format, this technique can be greatly robust, cost-efficient, readily automated, and scalable for parallel assays of hundreds of samples. The developed genotyping strategy might provide a robust, highly sensitive, and specific genotyping platform for genetic analysis and molecular diagnostics.


Assuntos
DNA Catalítico/metabolismo , Medições Luminescentes/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Polimorfismo de Nucleotídeo Único/genética , Sequência de Bases , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Genoma Humano/genética , Genótipo , Humanos , Sondas de Oligonucleotídeos/genética , Sondas de Oligonucleotídeos/metabolismo
17.
Anal Chem ; 82(4): 1358-64, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20078091

RESUMO

A new fluorescence method based on aptamer-target interactions has been developed for cocaine detection with target-induced strand displacement. Here we describe new probes, the hairpin-probe and the single strand-probe (ss-probe), that possess two recognition sequences of cocaine aptamer. In the presence of cocaine, both probes would associate with the target to form a tripartite complex. The conformational change in the hairpin-probe causes the opening of a hairpin structure and the hybridization to primer. With polymerase and the dNTPs, the replication of the single-stranded domain of hairpin-probe triggers the process of primer extension. When the hairpin-probe is converted into a fully double-stranded form, the ss-probe and cocaine are displaced to bind another hairpin-probe and initiate new amplification cycles. Fluorescence signal generation would be observed upon SYBR Green I intercalating into the new DNA double helix. The new protocol design permits detection of as low as 2 nM cocaine in a closed tube, offering a convenient approach for a homogeneous assay. Compared with previously reported cocaine aptameric sensors, our new method is highly sensitive, selective, and economical.


Assuntos
Aptâmeros de Nucleotídeos/genética , Técnicas Biossensoriais/métodos , Cocaína/análise , Técnicas de Amplificação de Ácido Nucleico , Aptâmeros de Nucleotídeos/química , Sequência de Bases , Cocaína/química , Primers do DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Replicação do DNA , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Eletroforese , Humanos , Sequências Repetidas Invertidas , Dados de Sequência Molecular , Espectrometria de Fluorescência , Fatores de Tempo
18.
Ai Zheng ; 27(6): 650-3, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18570743

RESUMO

BACKGROUND & OBJECTIVE: Overexpression of heat shock protein (HSP)70 is expressed in many tumors, but the correlation of its overexpression in nasopharyngeal carcinoma (NPC) to immunoglobin A against viral capsid antigen of Epstein-Barr virus (EBV) in sera and its clinical significance are still unclear. This study was to determine the expression of HSP70 in NPC, and to analyze its correlations to EBV IgA/VCA titer and prognosis. METHODS: The expression of HSP70 in 38 specimens of stage II-III NPC was determined by SP immunohistochemistry; the content of HSP70 in the 38 specimens was detected by ELISA; the EBV IgA/VCA titer in sera of the 38 patients was detected by immunoenzymatic (IE) method. RESULTS: The positive rate of HSP70 in the 38 NPC samples was 60.5%. HSP70 expression was positively correlated to EBV IgA/VCA titer (r=0.690, P=0.001), but not to sex, age, and clinical stage (P>0.05). The 5-year survival rates of HSP70-positive group and HSP70-negative group were 65.2% and 80.0%. The 5-year tumor-free survival rates of HSP70-positive group and HSP70-negative group were 40.0% and 78.6% (P=0.04). CONCLUSION: HSP70 expression in stage II-III NPC tissues is positively correlated to EBV IgA/VCA titer. The prognosis of HSP70-positive NPC patients is poor.


Assuntos
Antígenos Virais/imunologia , Proteínas do Capsídeo/imunologia , Proteínas de Choque Térmico HSP70/análise , Imunoglobulina A/sangue , Neoplasias Nasofaríngeas/química , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/virologia , Prognóstico
19.
Huan Jing Ke Xue ; 28(9): 2117-22, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17990568

RESUMO

The experiments were made in laboratory to analyze the effects of rhamnolipid on the biodegradation of n-hexadecane and the cell surface hydrophobicity using the microorganism ( Bacillus cereus DQ01 and Bacillus sp. DQ02). The results show that the optimal concentrations range of rhamnolipid were 0.4 mmol/L and 0.2 mmol/L, respectively, which can obviously enhance BATH(bacterial adherence to hydrocarbon). The degradation of n-hexadecane by Bacillus cereus DQ01 and Bacillus sp. DQ02 were increased 8.1% and 11.6%, respectively, within 48 h in the presence of the rhamnolipid than that of in the absence of the rhamnolipid. The growth of two strains and BATH increased with obviously in the presence of the rhamnolipid. Especially BATH of Bacillus sp. DQ02 was 44% in the presence of rhamnolipid, which was better than BATH of Bacillus cereus DQ01 without rhamnolipid. In contrast, glucose experiments showed that addition of rhamnolipid did not have much impact on growth of both strains and cell surface hydrophobicity. Moreover, the interfacial tension decreased with the addition of rhamnolipid. The rhamnolipid-treated cells had a rougher texture than the untreated cell.


Assuntos
Alcanos/metabolismo , Bacillus cereus/metabolismo , Glicolipídeos/química , Alcanos/química , Bacillus cereus/classificação , Biodegradação Ambiental , Interações Hidrofóbicas e Hidrofílicas , Tensoativos/química
20.
J Environ Sci (China) ; 19(12): 1496-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18277655

RESUMO

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils. Bidens maximowicziana is a new Pb hyperaccumulator, which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb. The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues. The Pb distribution order in the B. maximowicziana was: leaf > stem > root. The effect of amendments on phytoremediation was also studied. The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application. Compared with CK (control check), EDTA application promoted translocation of Pb to overground parts of the plant. The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg. This research demonstrated that B. maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil, especially, combination with EDTA.


Assuntos
Bidens/metabolismo , Quelantes/farmacologia , Ácido Edético/farmacologia , Chumbo/metabolismo , Poluentes do Solo/metabolismo , Bidens/efeitos dos fármacos , Bidens/crescimento & desenvolvimento , Biodegradação Ambiental/efeitos dos fármacos , Ácido Cítrico/farmacologia , Fosfatos/farmacologia , Componentes Aéreos da Planta/efeitos dos fármacos , Componentes Aéreos da Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo
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