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Sugarcane yellow leaf virus (SCYLV), a member of the genus Polerovirus in the family Luteoviridae, causes severe damage and represents a great threat to sugarcane cultivation and sugar industry development. In this study, inoculation of Nicotiana benthamiana plants with a potato virus X (PVX)-based vector carrying the SCYLV P0 gene induced typical mosaic, leaf rolling symptoms and was associated with a hypersensitive-like response (HLR) necrosis symptom, which is accompanied with a systemic burst of H2O2 and also leads to higher PVX viral genome accumulation levels. Our results demonstrate that SCYLV P0 is a pathogenicity determinant and plays important roles in disease development. To further explore its function in pathogenic processes, a yeast two-hybrid assay was performed to screen the putative P0-interacting host factors. The recombinant plasmid pGBKT7-P0 was constructed as a bait and transformed into the yeast strain Y2HGold. The ROC22 cultivar (an important parental resource of the main cultivar in China) cDNA prey library was constructed and screened by co-transformation with the P0 bait. We identified 28 potential interacting partners including those involved in the optical signal path, plant growth and development, transcriptional regulation, host defense response, and viral replication. To our knowledge, this is the first time we have reported the host proteins interacting with the P0 virulence factor encoded by sugarcane yellow leaf virus. This study not only provides valuable insights into elucidating the molecular mechanism of the pathogenicity of SCYLV, but also sheds light on revealing the probable new pathogenesis of Polerovirus in the future.
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Luteoviridae , Factores de Virulencia , Técnicas del Sistema de Dos Híbridos , Peróxido de Hidrógeno , Luteoviridae/genéticaRESUMEN
Bromodomain-containing protein 4 (BRD4), which is a member of the bromodomain and extra-terminal domain (BET) family, plays an important role in the regulation of gene expression as the "reader" of epigenetic regulation. BRD4 has become a promising target to treat cancer, because the up-regulation of BRD4 expression is closely associated with the occurrence and development of various cancers. At present, several BRD4 inhibitors are in clinical trials for cancer therapy, but no BRD4 inhibitors are on the market. Here, we designed and synthesized a series of compounds bearing pyrrolo[4,3,2-de]quinolin-2(1H)-one scaffold through structural modification of natural products ammosamide B, which is a natural pyrroloquinoline derivative reported for its potential antitumor activity. All target compounds were evaluated for their BRD4 BD1 inhibition activities via the protein thermal shift assays or AlphaSceen assay. The representative compound 49 showed potent activity (IC50 = 120 nM). The co-crystal of compound 49 with BRD4 BD1 was solved to study the structure activity relationship, which showed that 49 could combine with the acetyl lysine binding site and formed a hydrogen bond with the conserved residue Asn140. The results demonstrate that compound 49 is worthy of further investigation as a promising BRD4 inhibitor.
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Proteínas Nucleares , Quinolinas , Amidas , Epigénesis Genética , Compuestos Heterocíclicos con 3 Anillos , Pirroles , Quinolinas/farmacología , Relación Estructura-ActividadRESUMEN
Different housing conditions, including housing space and the physiological and social environment, may affect rodent behavior. Here, we examined the effects of different housing conditions on post-stroke angiogenesis and functional recovery to clarify the ambiguity about environmental enrichment and its components. Male rats in the model groups underwent right middle cerebral artery occlusion (MCAO) followed by reperfusion. The MCAO rats were divided into four groups: the physical enrichment (PE) group, the social enrichment (SE) group, the combined physical and social enrichment (PSE) group and the ischemia/reperfusion + standard conditioning (IS) group. The rats in the sham surgery (SS) group were housed under standard conditions. In a set of behavioral tests, including the modified Neurological Severity Score (mNSS), rotarod test, and adhesive removal test, we demonstrated that the animals in the enriched condition groups exhibited significantly improved neurological functions compared to those in the standard housing group. Smaller infarction volumes were observed in the animals of the PSE group by MRI detection. The enriched conditions increased the microvessel density (MVD) in the ischemic boundary zone, as revealed by CD31 immunofluorescent staining. The immunochemical and q-PCR results further showed that environmental enrichment increased the expression levels of angiogenic factors after ischemia/reperfusion injury. Our data suggest that all three enrichment conditions promoted enhanced angiogenesis and functional recovery after ischemia/reperfusion injury compared to the standard housing, while only exposure to the combination of both physical and social enrichment yielded optimal benefits.
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BACKGROUND: Post-stroke depression (PSD) is one of the most common stroke complications with high morbidity. Researchers have done much clinical research on Traditional Chinese Medicine (TCM) treatment, but very little research on diagnosis. Based on the thought of combination of disease and syndrome, this study will establish a unified and objective quantitative diagnosis model of TCM syndromes of PSD, so as to improve the clinical diagnosis and treatment of PSD. OBJECTIVE: First: To establish a unified and objective quantitative diagnosis model of TCM syndromes in PSD under different disease courses, and identify the corresponding main, secondary, and concurrent symptoms, which are based on the weighting factor of each TCM symptom. Second: To find out the relationship between different stages of PSD and TCM syndromes. Clarify the main syndrome types of PSD under different stages of disease. Reveal the evolution and progression mechanism of TCM syndromes of PSD. METHODS AND ANALYSIS: This is a retrospective study of PSD TCM diagnosis. Three hundred patients who were hospitalized in the First Teaching Hospital of Tianjin University of TCM with complete cases from January 2014 to January 2019 are planned to be recruited. The study will mainly collect the diagnostic information from the cases, find the related indicators of TCM and Western medicine in PSD, and clarify the relationship between different disease stages and TCM syndromes. Finally, the PSD TCM syndrome quantitative diagnosis model will be established based on the operation principle of Back Propagation (BP) artificial neural network. CONCLUSION: To collect sufficient medical records and establish models to speed up the process of TCM diagnosis.
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Depresión/diagnóstico , Medicina Tradicional China , Accidente Cerebrovascular/psicología , Adolescente , Adulto , Anciano , Depresión/terapia , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Síndrome , Adulto JovenRESUMEN
BACKGROUND: Cultivating the professional knowledge and professional identity of nursing students is important for nursing education. The degree of professional identity of nursing students will directly affect their career options and work performance after graduation. Clinical practice is a learning process of combining the knowledge and the practical techniques of nursing. It is the important way to cultivate the students' comprehensive ability, professional attitude and professional emotion. Effective clinical supervision during the clinical practice plays an important role in guaranteeing clinial practice quality and cultivating professional nursing students. Active teaching supervision is helpful to achieve the expected learning effect. Therefore, it is vital to evaluate the clinical supervision ability of the clinical nursing teachers. However, there is no special assessment instrument available in China. OBJECTIVES: To assess the validity and reliability of the Chinese version of the modified Clinical Supervision Self-Assessment Tool (mCAST). DESIGN: A cross sectional survey design with a convenience sample was used in this study. This cross-sectional psychometric instrumental study determined the reliability and validity of the Chinese version of the modified Clinical Supervision Self-Assessment Tool (mCAST). SETTINGS: Twelve hospitals in Tianjin, China. PARTICIPANTS: A total of 350 registered nurses who perform teaching tasks in clinical practice were recruited. METHODS: The Chinese version of the mCSAT was translated and tested by obtaining the authorization of the developer of the mCAST using Brislin's model (that is, translation, back translation, cultural adaptation and pilot study). A total of 350 registered nurses who perform teaching tasks in clinical practice were recruited by convenience sampling for the assessment of construct validity using exploratory factor analysis (EFA). Moreover, item analysis, internal correlation coefficients, Cronbach's alpha coefficients, test-retest realibility and split-half reliability were conducted to test the psychometric properties of the Chinese version of the mCSAT. RESULTS: The Chinese version of the mCSAT contained 2 subscales, namely, mCSAT-Knowledge and mCSAT-Skills. Exploratory factor analysis of the knowledge and skills subscales explained 63.26% and 63.60% of the total variances, respectively. The mCSAT-Knowledge subscale contains 3 dimensions, namely, evaluating learning (10 items), facilitating learning (9 items) and problem solving (10 items); the mCSAT-Skills subscale contains 3 dimensions, namely, evaluating learning (10 items), facilitating learning (9 items) and problem solving (10 items). The Cronbach's α coefficients of the mCSAT-Knowledge and mCSAT-Skills subscales were both 0.95. The split-half reliability of the mCSAT-Knowledge and mCSAT-Skills subscales were 0.88 and 0.89, respectively. CONCLUSION: The Chinese version of the mCSAT was reliable and valid in the evaluation of the knowledge and skills for the clinical supervision of registered nurses. Further validation of the Chinese version of the mCSAT requires a more representative and larger sample. Also, the confirmatory factor analysis should be conducted in future study.
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Autoevaluación (Psicología) , China , Estudios Transversales , Humanos , Proyectos Piloto , Psicometría , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
BACKGROUND: MiRNAs have been demonstrated to be important regulators during osteogenic differentiation in multiple types of stem cells. In the study, the interaction between miR-375 and TOB2 was analyzed to identify their functions on the proliferation and osteogenic differentiation of hPDLSCs. METHODS: hPDLSCs were isolated from human first premolars, and hPDLSCs stably expressing and silenced miR-375 were constructed using miR-375-ago and miR-375-antago, respectively. miR-375 and RUNX2 mRNA expression levels in hPDLSCs during osteogenic differentiation were investigated using qRT-PCR. The impact of miR-375 expression on hPDLSCs proliferation and osteogenic differentiation was determined using MTT assay, ALP assay, and alizarin red S staining. The protein expression levels of COL1A1, RUNX2 and OCN were detected using Western blot. The targeting of TOB2 by miR-375 was validated using dual luciferase reporter assay. RESULTS: The expression levels of miR-375 were increased in hPDLSCs during osteogenic differentiation in a time-dependant manner, and was positively correlated with RUNX2 mRNA expression. miR-375 facilitated the proliferation and osteogenic differentiation of hPDLSCs, and promoted the protein expression levels of COL1A1, RUNX2 and OCN. Moreover, TOB2 protein expression was reduced in hPDLSCs during osteogenic differentiation in a time-dependant manner, and miR-375 directly targeted TOB2 expression. In addition, targeting TOB2 expression in hPDLSCs could rescue the suppression of cell proliferation and osteogenic differentiation by miR-375-antago. CONCLUSION: In summary, miR-375 promotes proliferation and osteogenic differentiation of hPDLSCs by targeting TOB2, which reveals a new regulatory mechanism underlying osteogenic differentiation of hPDLSCs by miR-375/TOB2 axis.
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Proteínas de Ciclo Celular/metabolismo , MicroARNs/genética , Osteogénesis , Ligamento Periodontal/citología , Células Madre/citología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , HumanosRESUMEN
Ginkgo diterpene lactone (GDL) is the raw material for ginkgo diterpene lactone meglumine injection, which is used for treating cerebral ischemia. The aims of this study were to explore the cellular pharmacokinetics of GDL in whole cells and subcellular fractions, and detect cellular pharmacodynamics on the human SH-SY5Y cells induced by oxygen-glucose deprivation and reoxygenation (OGD/R). Firstly, a simple, sensitive and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for assessing the amount of ginkgolide A (GA), B (GB) and K (GK) in cellular/subcellular samples. Then, phosphatidylserine and mitochondria membrane potential were assayed to evaluate the extent of apoptosis effect. The study showed that the cellular/subcellular accumulation of GA and GB were increased in a concentration-dependent manner; the levels of GA and GB in cytosol were the highest among these subcellular organelles. Meanwhile, GDL also attenuated the OGD/R-induced increases in the percentage of apoptotic and mitochondria membrane potential. In addition, verapamil increased the rate and amount of GA and GB entering cellular/subcellular compartments through inhibition of P-glycoprotein activity, and promoted the protective effect of GDL. The present study reports the cellular pharmacokinetics profiles of GA and GB in normal and OGD/R-induced SH-SY5Y cells in vitro for the first time, which provided valuable information for clinical safety application.
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Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Diterpenos , Ginkgo biloba/química , Lactonas , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía Liquida , Diterpenos/química , Diterpenos/farmacocinética , Diterpenos/farmacología , Humanos , Lactonas/química , Lactonas/farmacocinética , Lactonas/farmacología , Límite de Detección , Modelos Lineales , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Extractos Vegetales/química , Reproducibilidad de los Resultados , Espectrometría de Masas en TándemRESUMEN
The aim of this study was to identify a microRNA (miRNA) expression signature for predicting HCC (hepatocellular carcinoma) survival. A total of 322 HCC patients in The Cancer Genome Atlas (TCGA) database were randomly divided into training and testing set. miRNAs, associated with survival time in the training set, were identified by using univariate Cox regression analysis. The risk score was formulated based on the expression levels of these miRNAs. Then the miRNA signature was validated in testing set through Kaplan-Meier analysis and log-rank test. hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468 were identified to formulate risk score in training set and used to calculate the risk score of each patients in testing set. About 161 patients in testing set were segregated into high- and low-risk group according to the median risk score. The survival time of high-risk group was significantly shorter (p = 0.0248) than low-risk group in testing test. The target genes of five miRNAs were significantly enriched in valine, leucine, and isoleucine degradation pathway and PPAR signaling pathway. hsa-miR-1468 had an up-regulated tendency in HCC tissues compared to adjacent tumor tissues. The expression of hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468, which might be potential biomarkers to evaluate HCC patients' prognosis.
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Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patología , Perfilación de la Expresión Génica , MicroARNs/análisis , Biomarcadores/análisis , Femenino , Humanos , Masculino , Pronóstico , Análisis de SupervivenciaRESUMEN
BACKGROUND: Temporal lobe epilepsy (TLE) is one of the most drug-resistant types of epilepsy with about 80% of TLE patients falling into this category. Increasing evidence suggests that neuroinflammation, which has a critical role in the epileptogenesis of TLE, is associated with microglial activation. Therefore, agents that act toward the alleviation in microglial activation and the attenuation of neuroinflammation are promising candidates to treat TLE. α-Asarone is a major active ingredient of the Acori Graminei Rhizoma used in Traditional Chinese Medicine, which has been used to improve various disease conditions including stroke and convulsions. In addition, an increasing number of studies suggested that α-asarone can attenuate microglia-mediated neuroinflammation. Thus, we hypothesized that α-asarone is a promising neuroprotective agent for the treatment of the TLE. METHODS: The present study evaluated the therapeutic effects of α-asarone on microglia-mediated neuroinflammation and neuroprotection in vitro and in vivo, using an untreated control group, a status epilepticus (SE)-induced group, and an SE-induced α-asarone pretreated group. A pilocarpine-induced rat model of TLE was established to investigate the neuroprotective effects of α-asarone in vivo. For the in vitro study, lipopolysaccharide (LPS)-stimulated primary cultured microglial cells were used. RESULTS: The results indicated that the brain microglial activation in the rats of the SE rat model led to important learning and memory deficit. Preventive treatment with α-asarone restrained microglial activation and reduced learning and memory deficit. In the in vitro studies, α-asarone significantly suppressed proinflammatory cytokine production in primary cultured microglial cells and attenuated the LPS-stimulated neuroinflammatory responses. Our mechanistic study revealed that α-asarone inhibited inflammatory processes by regulation the transcription levels of kappa-B, by blocking the degradation pathway of kappa B-alpha [inhibitor kappa B-alpha (IκB-α)] and kappa B-beta (IκB-ß) kinase in both the SE rats and in primary cultured microglial cells. CONCLUSION: Taken together, these data demonstrate that α-asarone is a promising neuroprotective agent for the prevention and treatment of microglia-mediated neuroinflammatory conditions including TLE, for which further assessment studies are pertinent.
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The aim of this study was to explore the relationships among study engagement, learning adaptability, and time management disposition in a sample of Chinese baccalaureate nursing students. A convenient sample of 467 baccalaureate nursing students was surveyed in two universities in Tianjin, China. Students completed a questionnaire that included their demographic information, Chinese Utrecht Work Engagement Scale-Student Questionnaire, Learning Adaptability Scale, and Adolescence Time Management Disposition Scale. One-way analysis of variance tests were used to assess the relationship between certain characteristics of baccalaureate nursing students. Pearson correlation was performed to test the correlation among study engagement, learning adaptability, and time management disposition. Hierarchical linear regression analyses were performed to explore the mediating role of time management disposition. The results revealed that study engagement (F = 7.20, P < .01) and learning adaptability (F = 4.41, P < .01) differed across grade groups. Learning adaptability (r = 0.382, P < .01) and time management disposition (r = 0.741, P < .01) were positively related with study engagement. Time management disposition had a partially mediating effect on the relationship between study engagement and learning adaptability. The findings implicate that educators should not only promote interventions to increase engagement of baccalaureate nursing students but also focus on development, investment in adaptability, and time management.
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Bachillerato en Enfermería , Estudiantes de Enfermería , Administración del Tiempo , Adolescente , Adulto , China , Humanos , Adulto JovenRESUMEN
The clinical efficacy of acupuncture and moxibustion for post-stroke constipation was systematically reviewed. By computerized and manual retrieval of clinical research literature regarding acupuncture and moxibustion for post-stroke constipation, the randomized control trials (RCTs) that met the inclusive criteria were collected. Cochrane systematic review method was used and Revmen 5.2 software was adopted to perform this Meta analysis. Totally 8 articles were included, involving 610 cases of post-stroke constipation. As a result, the total effective rate and cured rate of acupuncture and moxibustion for post-stroke constipation were significantly superior to those of the control group [total effective rate: OR = 2.10, 95% CI (1.25, 3.54), Z = 2.78, P = 0.005; cured rate: OR = 2.37, 95% CI (1.57, 3.58), Z = 4.10, P < 0.0001]. This result indicated that acupuncture was effective for post-stroke constipation and had some advantages compared with other therapies. But the quality of included RCTs was low, and high-quality, large-sample and multi-center RCTs were needed to perform further verification.
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Terapia por Acupuntura , Estreñimiento/terapia , Moxibustión , Accidente Cerebrovascular/complicaciones , Estreñimiento/etiología , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
The fibroblast growth factors (FGFs) are important for embryo development, wound healing, hematopoiesis, and angiogenesis. FGF-1, a member of FGF family, is involved in both receptor-dependent pathways and an intracrine pathway. Studies have recently shown that FGF-1 is overexpressed in the early stages of several kinds of cancer. Thus, FGF-1 is a candidate for cancer immunotargeting. To study the potential use of therapeutic antibodies against FGF-1, a monoclonal hybridoma 1C9 secreting monoclonal antibody specific for FGF-1 was developed. Then, a single-chain variable fragment (scFv) antibody was genetically engineered from hybridama 1C9. The binding of the scFv1C9 to the antigen FGF-1 was demonstrated by ELISA and immunoprecipitation assays. Functional analysis showed that the overexpressed scFv1C9 in MCF-7 cells targeted endogenous FGF-1 and prevented the translocation of FGF-1 into the nucleus, resulting in the blockade of the intracrine pathway of FGF-1, which caused the G1 arrest by p21 up-regulation. These results suggest that the generated scFv1C9 is an effective inhibitor of the intracrine pathway of FGF-1 and has a potential application as anti-tumoral agent in breast cancer.
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Antineoplásicos/farmacología , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/metabolismo , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal/efectos de los fármacos , Anticuerpos de Cadena Única/farmacología , Animales , Antineoplásicos/inmunología , Antineoplásicos/uso terapéutico , Secuencia de Bases , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Escherichia coli , Femenino , Factor 1 de Crecimiento de Fibroblastos/genética , Expresión Génica , Humanos , Hibridomas/química , Hibridomas/metabolismo , Inmunomodulación , Ratones , Datos de Secuencia Molecular , Terapia Molecular Dirigida/métodos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/uso terapéutico , Regulación hacia ArribaRESUMEN
Ultra-small Fe(3)O(4) nanoparticles were prepared by using the coprecipitation method, in which the polyvinylpyrrolidone (PVP) serves as a stabilizer. The nanoparticles were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), infra spectrum (IR), X-ray photoelectron spectroscopy (XPS) and in vivo magnetic resonance imaging (MRI) test. The results showed that the particles' size was determined by the dripping rate and that PVP molecules played the role of preventing the aggregation and restricting the size of Fe(3)O(4) nanoparticles. The Fe(3)O(4) nanoparticles with diameter from 6.5 to 1.9 nm obviously exhibited negative contrast enhancement and concentrated at the target area guided by a permanent magnet.
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Materiales Biocompatibles Revestidos/síntesis química , Medios de Contraste/síntesis química , Compuestos Férricos/química , Imagen por Resonancia Magnética , Nanopartículas del Metal , Povidona/química , Animales , Materiales Biocompatibles Revestidos/química , Medios de Contraste/química , Excipientes/química , Excipientes/farmacología , Imagen por Resonancia Magnética/métodos , Magnetismo , Ensayo de Materiales , Nanopartículas del Metal/química , Ratones , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Povidona/farmacología , Difracción de Rayos XRESUMEN
A new strategy for assembling multifunctional nanocomposites with magnetic particles and amino dendrimers was reported. In this strategy, the amino terminated PAMAM G5.0 and Fe(3)O(4) NPs prepared by co-deposition method and further modified by aminosilane by two sol-gel processes were combined with the hydrophilic spacer of PEG dicarboxylate by amidation. The nanocomposites were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), atom force microscopy (AFM), superconducting quantum interference device (SQUID) magnetometer, and hydrophilicity analysis. The results showed that the multifunctional nanocomposites were spherical with the mean diameter of 180 nm and exhibited good dispersion and hydrophilicity. The new strategy put forward here provides an effective route to functionalizing Fe(3)O(4) NPs with various amino dendrimers for drug and gene delivery as well as biological detection.
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Dendrímeros , Compuestos Férricos/química , Nanocompuestos , Magnetismo , Microscopía Electrónica de Transmisión , Difracción de Rayos XRESUMEN
A molecular spectroscopic investigation of the interaction of phenacyl thiazolium bromide (PTB) and bovine serum albumin (BSA) or human serum albumin (HSA) is reported employing fluorescence quenching techniques. It is determined that the maximal excitation wavelength is 280 nm for BSA solution, and 290 nm for HAS solution. When PTB was added into these solutions gradually, the emission peaks were decreased obviously, which are typical quenching phenomena. The results obtained reveal that there is a medium-intensity binding affinity for PTB with HSA and BSA. At 15 degrees C, the binding constants of PTB and BSA (HSA) are 3.66 x 10(3) and 3.83 x 10(3), and the numbers of binding sites are 1.02 and 1.06 respectively. At 37 degrees C, the binding constants of PTB and BSA (HSA) are 3.58 x 10(3) and 3.35 x 10(3), and the numbers of binding sites are 0.95 and 0.87 respectively. According to the thermodynamic parameters, the main sort of the binding force between the drug and BSA or HSA was electrostatic force. Based on the Föster non-radiation energy transfer theory, it could be acquired that the distance between BSA or HSA and PTB is 7.5 or 7.9 nm. According to the crystal structure of serum albumin, it can be speculated that subdomain II A was the binding sites for the interaction of PTB and serum albumin, which is the region near Try214.