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1.
Acta Radiol ; : 2841851241259924, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881364

RESUMO

BACKGROUND: Few studies have investigated the feasibility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using a free-breathing golden-angle radial stack-of-stars volume-interpolated breath-hold examination (FB radial VIBE) sequence in the lung. PURPOSE: To investigate whether DCE-MRI using the FB radial VIBE sequence can assess morphological and kinetic parameters in patients with pulmonary lesions, with computed tomography (CT) as the reference. MATERIAL AND METHODS: In total, 43 patients (30 men; mean age = 64 years) with one lesion each were prospectively enrolled. Morphological and kinetic features on MRI were calculated. The diagnostic performance of morphological MR features was evaluated using a receiver operating characteristic (ROC) curve. Kinetic features were compared among subgroups based on histopathological subtype, lesion size, and lymph node metastasis. RESULTS: The maximum diameter was not significantly different between CT and MRI (3.66 ± 1.62 cm vs. 3.64 ± 1.72 cm; P = 0.663). Spiculation, lobulation, cavitation or bubble-like areas of low attenuation, and lymph node enlargement had an area under the ROC curve (AUC) >0.9, while pleural indentation yielded an AUC of 0.788. The lung cancer group had significantly lower Ktrans, Ve, and initial AUC values than the other cause inflammation group (0.203, 0.158, and 0.589 vs. 0.597, 0.385, and 1.626; P < 0.05) but significantly higher values than the tuberculosis group (P < 0.05). CONCLUSION: Morphology features derived from FB radial VIBE have high correlations with CT, and kinetic analyses show significant differences between benign and malignant lesions. DCE-MRI with FB radial VIBE could serve as a complementary quantification tool to CT for radiation-free assessments of lung lesions.

2.
PLoS One ; 19(4): e0297766, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38648228

RESUMO

OBJECTIVE: This study comprehensively evaluated the causal relationship between different types of statins use and knee/hip osteoarthritis (OA) using a two-sample and multivariate Mendelian randomization (MR) method. METHODS: MR analysis was conducted using publicly available summary statistics data from genome-wide association studies (GWAS) to assess the causal associations between total statins use (including specific types) and knee/hip OA. The primary analysis utilized the inverse variance-weighted (IVW) method, with sensitivity analysis conducted to assess robustness. Multivariable MR (MVMR) analysis adjusted for low-density lipoprotein cholesterol (LDL-C), intermediate-density lipoprotein cholesterol (IDL-C), high-density lipoprotein cholesterol (HDL-C), and body mass index (BMI). RESULTS: The MR analysis revealed a significant inverse association between genetically predicted total statins use and the risk of knee OA (OR = 0.950, 95%CI: 0.920-0.982, p = 0.002) as well as hip OA (OR = 0.932, 95%CI: 0.899-0.966, p <0.001). Furthermore, this study highlighted a reduced risk of knee/hip OA with the use of atorvastatin and simvastatin. Rosuvastatin use was associated with a decreased risk of hip OA but showed no association with knee OA. MVMR results indicated no correlation between exposure factors and outcomes after adjusting for LDL-C or IDL-C. HDL-C may not significantly contribute to statin-induced osteoarthritis, while BMI may play an important role. CONCLUSION: This study provides compelling evidence of the close relationship between statin use and a reduced risk of knee/hip OA, particularly with atorvastatin and simvastatin. LDL-C and IDL-C may mediate these effects. These findings have important implications for the clinical prevention and treatment of knee/hip OA.


Assuntos
Estudo de Associação Genômica Ampla , Inibidores de Hidroximetilglutaril-CoA Redutases , Análise da Randomização Mendeliana , Osteoartrite do Quadril , Osteoartrite do Joelho , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/epidemiologia , Osteoartrite do Quadril/genética , LDL-Colesterol/sangue , Sinvastatina/uso terapêutico , Sinvastatina/efeitos adversos , Índice de Massa Corporal , HDL-Colesterol/sangue , Polimorfismo de Nucleotídeo Único , Fatores de Risco
3.
Rev Sci Instrum ; 94(2): 025006, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859003

RESUMO

To solve the problem of multiphase holdup measurement, a new dual-receiver fiber-optical probe array multiphase logging tool (NDRFOPA_MLT) is designed and developed. This paper first constructed the mechanism model of an NDRFOP for phase holdup measurement by using the ray tracing method and theoretically analyzed the feasibility of NDRFOP to measure phase holdup; considering the shortcomings of NDRFOP local measurement, a NDRFOPA sensor for oil production three-phase flow is designed and developed. At the same time, the volume of fluid model was used to simulate the distribution characteristics of the medium in the NDRFOPA_MLT measurement pipeline under the working conditions of oil-gas-water flow with a total flow rate range of 0.42-1.25 m3/h, water holdup range of 50%-80%, oil holdup range of 10%-30%, and gas holdup range of 10%-40%. In addition, the NDRFOPA_MLT measurement models for different multiphase flow conditions were established by the ZEMAX ray tracing method, and the sensitivity distribution, response characteristics, and phase holdup measurement methods were studied to obtain the phase holdup measurement results under multiphase flow conditions. Finally, a multiphase flow experimental platform with a measurement pipe diameter of 20 mm and a measurement pipe length of 300 mm was established, and experiments were conducted under multiphase flow conditions, such as a gas flow rate range of 0.04-0.16 m3/h, oil flow rate range of 0.64-1.70 m3/h, and water flow rate range of 0.53-2.58 m3/h. The experimental results showed that phase holdup measurement error was mainly kept within 10%.

4.
Front Physiol ; 12: 770051, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34819876

RESUMO

Ca2+ sparks are the elementary Ca2+ release events in cardiomyocytes, altered properties of which lead to impaired Ca2+ handling and finally contribute to cardiac pathology under various diseases. Despite increasing use of machine-learning algorithms in deciphering the content of biological and medical data, Ca2+ spark images and data are yet to be deeply learnt and analyzed. In the present study, we developed a deep residual convolutional neural network method to detect Ca2+ sparks. Compared to traditional detection methods with arbitrarily defined thresholds to distinguish signals from noises, our new method detected more Ca2+ sparks with lower amplitudes but similar spatiotemporal distributions, thereby indicating that our new algorithm detected many very weak events that are usually omitted when using traditional detection methods. Furthermore, we proposed an event-based logistic regression and binary classification model to classify single cardiomyocytes using Ca2+ spark characteristics, which to date have generally been used only for simple statistical analyses and comparison between normal and diseased groups. Using this new detection algorithm and classification model, we succeeded in distinguishing wild type (WT) vs RyR2-R2474S± cardiomyocytes with 100% accuracy, and vehicle vs isoprenaline-insulted WT cardiomyocytes with 95.6% accuracy. The model can be extended to judge whether a small number of cardiomyocytes (and so the whole heart) are under a specific cardiac disease. Thus, this study provides a novel and powerful approach for the research and application of calcium signaling in cardiac diseases.

5.
Front Microbiol ; 12: 627785, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679650

RESUMO

The type VI secretion system (T6SS), a macromolecular machine, plays an important role in the pathogenicity of many Gram-negative bacteria. However, the role of T6SS in the pathogenicity of Pseudomonas syringae pv. actinidiae (Psa), the pathogen of kiwifruit bacterial canker, is yet to be studied. Here, we found a T6SS gene cluster consisting of 13 core genes (A-J) in the genome of Psa M228 based on a genome-wide analysis. To determine whether the T6SS gene cluster affects the pathogenicity of Psa M228, T6SS and its 13 core gene deletion mutants were constructed and their pathogenicity was determined. The deletion mutants showed different degrees of reduction in pathogenicity compared with the wild-type strain M228; in tssM and tssJ mutants, pathogenicity was significantly reduced by 78.7 and 71.3%, respectively. The pathogenicity results were also confirmed by electron microscopy. To further confirm that the reduction in pathogenicity is related to the function of T6SS, we selected the T6SS gene cluster, comprising tssM and tssJ, for further analyses. Western blot results revealed that tssM and tssJ were necessary for hemolytic co-regulatory protein secretion, indicating that they encode a functional T6SS. Further, we explored the mechanism by which T6SS affects the pathogenicity of Psa M228. The ability of bacterial competition, biofilm formation, hydrogen peroxide tolerance, and proteolytic activity were all weakened in the deletion mutants M228ΔT6SS, M228ΔtssM, and M228ΔtssJ. All these properties of the two gene complementation mutants were restored to the same levels as those of the wild-type strain, M228. Quantitative real-time results showed that during the interaction between the deletion mutant M228ΔT6SS and the host, expression levels of T3SS transcriptional regulatory gene hrpR, structural genes hrpZ, hrcC, hopP1, and effector genes hopH1 and hopM1 were down-regulated at different levels. Taken together, our data provide evidence for the first time that the T6SS plays an important role in the pathogenicity of Psa, probably via effects on bacterial competition, biofilm formation, and environmental adaptability. Moreover, a complicated relationship exists between T6SS and T3SS.

6.
Lab Med ; 52(1): 86-92, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-32754755

RESUMO

OBJECTIVE: Cardiovascular diseases (CVDs) are important complications for patients with rheumatoid arthritis (RA). The study aimed to explore whether serum leptin is associated with a increased risk of cardiovascular (CV) events in patients with RA. METHODS: Two hundred twenty-three patients with RA were followed for a mean of 40 (range = 8-42) months. Serum leptin levels were measured at baseline. Cox regression analysis was performed to assess the association between leptin levels and the risk of CV events. RESULTS: The univariate analysis showed that patients with RA with higher serum leptin levels had higher rates of CV events and CV mortality, respectively (P <.001). The logistic regression model showed that leptin was independently related to CVD history (odds ratio = 1.603, 95% confidence interval [CI], 1.329-2.195; P =.005) after adjusting for confounding factors in patients with RA at baseline. The multivariate Cox proportional hazard model suggested that leptin was an independent prognostic factor for CV events in patients with RA after adjustments were made for clinical confounding factors (hazard ratio = 2.467, 95% CI, 2.019-4.495; P <.001). The Kaplan-Meier analysis showed that compared with patients with RA with leptin levels below the median value (≤15.4 mg/L), patients with leptin above the median value (>15.4 µg/L) had a higher rate of CV events (P <.001). CONCLUSION: Leptin was significantly associated with CV events in patients with RA. Elevated serum leptin levels may be a reliable prognostic factor for predicting CV complications in patients with RA.


Assuntos
Artrite Reumatoide/complicações , Doenças Cardiovasculares/etiologia , Leptina/sangue , Idoso , Artrite Reumatoide/sangue , Doenças Cardiovasculares/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais
7.
Risk Manag Healthc Policy ; 13: 1489-1497, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982507

RESUMO

BACKGROUND: Anxiety, depression and perceived stress are risk factors for adverse health problems. Inflammation participates in the development of chronic diseases such as psychiatric disorders. This study explored the relationships between inflammatory biomarkers and depression, anxiety and perceived stress in an obese adult population. METHODS: The relationships between psychological scores and inflammatory markers were analyzed. RESULTS: A higher BMI was not correlated with a higher anxiety score (P=0.152); however, BMI was positively associated with a higher depression score (P<0.001) and a higher perceived stress score (P<0.001). Multivariate linear regression analysis revealed that in participants with BMI≥30 and 25≤BMI<30, depression and perceived stress were significantly and independently associated with ICAM-1, E-selectin and CRP, but these associations were not observed in participants with BMI<25. The anxiety score was not associated with any inflammatory marker in any group of subjects, as determined by multivariate analysis. CONCLUSION: Depression and perceived stress were strongly associated with increased serum levels of pro-inflammatory markers, including ICAM-1, E-selectin and CRP, among a general obese population from the United States. These results further suggest that depression and perceived stress might also be chronic systemic inflammatory diseases.

8.
Mol Plant Pathol ; 20(7): 923-942, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31025813

RESUMO

Bacterial canker of kiwifruit, is a severe global disease caused by Pseudomonas syringae pv. actinidiae (Psa). Here, we found that Psa biovar 3 (Psa3) was the only biovar consisting of three widely distributed clades in the largest Chinese kiwifruit cultivated area. Comparative genomics between the three clades revealed 13 polymorphic genes, each of which had multiple intra-clade variations. For instance, we confirmed that the polymorphic copA gene, which encodes a periplasmic protein CopA that is translocated by the Twin-arginine targeting (Tat) system, was involved in copper tolerance. We also found extensive variation in pathogenicity amongst strains within each genetically monomorphic clade. Accordingly, the pathogenic determinants of Psa3 were identified via a genomic comparison of phenotypically different strains within each clade. A case study of the high- and low-virulence strains in the clade 2 of Psa3 revealed that an hfq variant involved in in vitro growth and virulence, while a conserved locus 930 bp upstream of the hrpR gene in the Type III secretion system (T3SS) cluster was required for full pathogenicity on kiwifruit and elicitation of the hypersensitivity response on non-host Nicotiana benthamiana. The '-930' locus is involved in transcriptional regulation of hrpR/S and modulates T3SS function via the hierarchical 'HrpR/S-HrpL-T3SS/effector' regulatory cascade in Psa. Our results provide insights into the molecular basis underlying the genetic diversification and evolution of pathogenicity in Psa3 since kiwifruit canker emerged in China in the 1980s.


Assuntos
Loci Gênicos , Genômica , Pseudomonas syringae/genética , Pseudomonas syringae/patogenicidade , Actinidia/microbiologia , Sequência Conservada/genética , Genes Bacterianos , Funções Verossimilhança , Mutagênese/genética , Filogenia , Doenças das Plantas/microbiologia , Polimorfismo Genético , Pseudomonas syringae/crescimento & desenvolvimento
9.
Mol Plant Pathol ; 19(6): 1353-1363, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28960871

RESUMO

Apple Valsa canker, caused by the fungus Valsa mali, is one of the most destructive diseases of apple trees in East Asia. Feruloyl esterases (ferulic acid esterases, FAEs), which belong to a subclass of carboxylic esterases, can cleave ester bonds that crosslink hydroxycinnamic acids and arabinoxylans or certain pectins in plant cell walls. However, a pathogenic role of FAE has not been demonstrated in plant-pathogenic fungi. In this study, the FAE gene family, including one type A, one type B, three type C and two type D FAE genes, was identified in V. mali. Five of the seven FAE genes had highly elevated transcript levels in V. mali-apple tree bark interactions compared with mycelia grown in axenic culture. Signal peptides of the VmFAEs were confirmed using yeast signal sequence trap assays. To examine whether FAEs are required for the pathogenicity of V. mali, seven single- and six double-gene deletion mutants were generated. Compared with the wild-type, three of the seven FAE single-deletion mutants showed significantly reduced pathogenicity and three of the six FAE double-deletion mutants exhibited greater reductions in pathogenicity, suggesting the joint action of FAEs in the V. mali-apple tree interaction. Most of the FAE mutants that exhibited a significant reduction in pathogenicity had significantly lower FAE activity than the wild-type fungus. These results indicate that secreted FAEs are required for the full pathogenicity of the phytopathogenic fungus V. mali.


Assuntos
Ascomicetos/patogenicidade , Hidrolases de Éster Carboxílico/metabolismo , Malus/metabolismo , Malus/microbiologia , Doenças das Plantas/microbiologia , Hidrolases de Éster Carboxílico/genética , Malus/genética , Virulência/genética
10.
Rev Sci Instrum ; 88(11): 115003, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29195385

RESUMO

In order to accurately measure the flow rate under the low yield horizontal well conditions, an auto-cumulative flowmeter (ACF) was proposed. Using the proposed flowmeter, the oil flow rate in horizontal oil-water two-phase segregated flow can be finely extracted. The computational fluid dynamics software Fluent was used to simulate the fluid of the ACF in oil-water two-phase flow. In order to calibrate the simulation measurement of the ACF, a novel oil flow rate measurement method was further proposed. The models of the ACF were simulated to obtain and calibrate the oil flow rate under different total flow rates and oil cuts. Using the finite-element method, the structure of the seven conductance probes in the ACF was simulated. The response values for the probes of the ACF under the conditions of oil-water segregated flow were obtained. The experiments for oil-water segregated flow under different heights of the oil accumulation in horizontal oil-water two-phase flow were carried out to calibrate the ACF. The validity of the oil flow rate measurement in horizontal oil-water two-phase flow was verified by simulation and experimental results.

11.
G3 (Bethesda) ; 7(4): 1259-1265, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28228472

RESUMO

Sexual reproduction in filamentous ascomycetes is controlled by the mating type (MAT) locus, including two idiomorphs MAT1-1 and MAT1-2 Understanding the MAT locus can provide clues for unveiling the sexual development and virulence factors for fungal pathogens. The genus Valsa (Sordariomycetes, Diaporthales) contains many tree pathogens responsible for destructive canker diseases. The sexual stage of these ascomycetes is occasionally observed in nature, and no MAT locus has been reported to date. Here, we identified the MAT locus of the apple canker pathogen Valsa mali, which causes extensive damage, and even death, to trees. V. mali is heterothallic in that each isolate carries either the MAT1-1 or MAT1-2 idiomorph. However, the MAT structure is distinct from that of many other heterothallic fungi in the Sordariomycetes. Two flanking genes, COX13 and APN2, were coopted into the MAT locus, possibly by intrachromosomal rearrangement. After the acquisition of foreign genes, unequal recombination occurred between MAT1-1/2 idiomorphs, resulting in a reverse insertion in the MAT1-2 idiomorph. Evolutionary analysis showed that the three complete MAT1-1-2, COX13, and APN2 genes in this region diverged independently due to different selection pressure. Null hypothesis tests of a 1:1 MAT ratio of 86 V. mali isolates from four different provinces showed a relatively balanced distribution of the two idiomorphs in the fields. These results provide insights into the evolution of the mating systems in Sordariomycetes.


Assuntos
Ascomicetos/genética , Genes Fúngicos Tipo Acasalamento , Malus/microbiologia , Doenças das Plantas/genética , Recombinação Genética , Ascomicetos/ultraestrutura , Sequência de Bases , Evolução Molecular , Filogenia , Especificidade da Espécie
12.
Yi Chuan ; 37(10): 1061-72, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-26496759

RESUMO

The CRISPR/Cas9 genome editing technique is a powerful tool for researchers. However, off-target effects of the Cas9 nuclease activity is a recurrent concern of the CRISPR system. Thus, designing sgRNA (single guide RNA) with minimal off-target effects is very important. sgRNAcas9 is a software package, which can be used to design sgRNA and to evaluate potential off-target cleavage sites. In this study, a graphical user interface for sgRNAcas9 was developed using the Java programming language. In addition, off-target effect for sgRNAs was evaluated according to mismatched number and "seed sequence" specification. Moreover, sgRNAcas9 software was used to design 34 124 sgRNAs, which can target 4691 microRNA (miRNA) precursors from human, mouse, rat, pig, and chicken. In particular, the off-target effect of a sgRNA targeting to human miR-206 precursor was analyzed, and the on/off-target activity of this sgRNA was validated by T7E1 assay in vitro. Taken together, these data showed that the interface can simplify the usage of the sgRNAcas9 program, which can be used to design sgRNAs for the majority of miRNA precursors. We also found that the GC% of those sgRNAs ranged from 40% to 60%. In summary, the sgRNAcas9 software can be easily used to design sgRNA with minimal off-target effects for any species. The software can be downloaded from BiooTools website (http://www.biootools.com/).


Assuntos
Sistemas CRISPR-Cas , Endonucleases/metabolismo , RNA Guia de Cinetoplastídeos/metabolismo , Software , Animais , Galinhas , Biologia Computacional/métodos , Humanos , Internet , Camundongos , MicroRNAs/genética , Linguagens de Programação , Precursores de RNA/genética , Ratos , Reprodutibilidade dos Testes , Suínos , Interface Usuário-Computador
13.
Chin Med J (Engl) ; 125(24): 4514-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23253729

RESUMO

Cystic tumour of the atrioventricular node is a rare primary cardiac tumour that can cause complete heart block and sudden death. Here, we describe a male case aged 42 years who suddenly died without a medical and family history of cardiac illnesses. After detailed macroscopic and microscopic examinations, a cystic mass was found in the atrioventricular nodal region. The small lesion was less than 1 cm in diameter, and consisted of small and large cystic spaces and tubular structures lined by flat, cuboidal or squamous epithelium. Immunohistochemical staining revealed the tumour epithelium positive for epithelial membrane antigen, carcinoembryonic antigen, antigen epitopes AE1/AE3, cytokeratins CK5/6 and CK7, but negative for calretinin, HBME-1, Wilms' tumor 1, factor VIII, chromogranin, synaptophysin or smooth muscle actin, suggesting an endodermal rather than mesothelial origin.


Assuntos
Nó Atrioventricular/patologia , Neoplasias Cardíacas/diagnóstico , Adulto , Nó Atrioventricular/metabolismo , Neoplasias Cardíacas/metabolismo , Humanos , Imuno-Histoquímica , Masculino
14.
BMC Complement Altern Med ; 11: 80, 2011 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-21943157

RESUMO

BACKGROUND: Many formulae of traditional Chinese medicines (TCMs) have been used for antiasthma treatment dating back many centuries. There is evidence to suggest that TCMs are effective as a cure for this allergenic disease administered via gastric tubes in animal studies; however, their efficacy, safety and side effects as an asthmatic therapy are still unclear. METHODS: In this study, guinea pigs sensitized with ovalbumin (OVA) were used as an animal model for asthma challenge, and the sensitization of animals by bronchial reactivity to methacholine (Mch) and the IgE concentration in the serum after OVA challenge were estimated. Complex traditional Chinese herbs (CTCM) were administered to the animals by nebulization, and the leukocytes were evaluated from bronchoalveolar lavage fluid (BALF). RESULTS: The results showed that inhalation of CTCM could abolish the increased lung resistance (13-fold increase) induced by challenge with OVA in the early asthmatic response (EAR), reducing to as low as baseline (1-fold). Moreover, our results indicated higher IgE levels (range, 78-83 ng/ml) in the serum of sensitized guinea pigs than in the unsensitized controls (0.9 ± 0.256 ng/ml). In addition, increased total leukocytes and higher levels of eosinophils and neutrophils were seen 6 hours after challenge, and the increased inflammatory cells were reduced by treatment with CTCM inhalation. The interleukin-5 (IL-5) level in BALF was also reduced by CTCM. CONCLUSION: Our findings indicate a novel method of administering traditional Chinese medicines for asthma treatment in an animal model that may be more effective than traditional methods.


Assuntos
Asma/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Ovalbumina/efeitos adversos , Administração por Inalação , Animais , Asma/induzido quimicamente , Asma/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Modelos Animais de Doenças , Cobaias , Humanos , Imunoglobulina E/imunologia , Interleucina-5/imunologia , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Masculino
15.
Artigo em Inglês | MEDLINE | ID: mdl-15777205

RESUMO

The experimental determination of the binding constant of a drug for its target molecule is of considerable importance. It is a basic experimental parameter in a variety of studies, such as the prediction of drug efficiency, or in the pharmacokinetic drug interaction. DNA-binding drugs have been reported to be able to interfere in a sequence dependent manner with biological functions such as topoisomerase activity, restriction of enzyme cleavage of DNA, protein-DNA interactions and the activity of transcription factors, leading to alteration of gene expression. This effect could have important practical application in the experimental therapy of human pathologies, including neoplastic diseases and viral, or microbial infections. The assessment of the biological activity of DNA-binding drugs by polymerase chain reaction, footprinting, gel retardation and in vitro transcription studies was recently reported. However, most of these techniques are steady-state methodologies and therefore are not suitable for an easy determination of the binding activity of DNA-binding drugs to target DNA and the stability of drugs-DNA complexes. Direct real-time observation and measurement of the interaction between DNA-binding drug and target DNA sequence is a subject of interest for drug discovery and development. The recent development of biosensors, based on surface plasmon resonance (SPR) technology, enables monitoring of a variety of biospecific interactions of DNA-binding drugs with target DNA elements in real-time. The present review is designed to indicate the theoretical background of SPR-based biosensor technology as well as to present the great variety of measurements and modes of interaction kinetics that can be performed with these techniques. In addition, some of the most recent studies in determining the binding constant and stoichiometry of DNA-binding drugs to target DNA with SPR technology are reviewed and the available theoretical aspects necessary for the comprehension of the experiments are provided.


Assuntos
DNA/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Preparações Farmacêuticas/metabolismo , Ressonância de Plasmônio de Superfície/métodos , Animais , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , DNA/genética , Humanos , Preparações Farmacêuticas/administração & dosagem
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