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1.
Anal Biochem ; 628: 114262, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34038704

RESUMEN

Cancer is the second leading cause of death worldwide and most of the cancer-related deaths result from metastasis. As expressed on the surface of various cancer cell types, intercellular adhesion molecule-1 (ICAM-1) has been shown to play a role in the attachment, invasion and migration of tumor cells. In this study, DNA aptamers were generated against ICAM-1 by cell-SELEX and protein SELEX method using ICAM-1(+) CHO-ICAM-1 cells and ICAM-1 protein, respectively. The pools obtained at the end of the 10th round of both SELEX were sequenced and the most enriched sequences were characterized for their binding behaviors and affinities to ICAM-1(+) CHO-ICAM-1 and ICAM-1(-) MIA PaCa-2 cells. Moreover, the inhibition abilities of sequences on migration and invasion were measured. The seven aptamer sequences were obtained selectively binding to CHO-ICAM-1 cells with Kd values in the ranging from 13.8 to 47.1 nM. Four of these aptamers showed inhibition in both migration and invasion of CHO-ICAM-1 cells at least 61%. All these results suggested that these aptamers have potential to detect specifically ICAM-1 expressing tumor cells and inhibit migration and invasion by blocking ICAM-1 related interactions of circulating tumor cells.


Asunto(s)
Aptámeros de Nucleótidos/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Técnica SELEX de Producción de Aptámeros , Animales , Aptámeros de Nucleótidos/química , Sitios de Unión , Movimiento Celular , Células Cultivadas , Cricetulus , Citometría de Flujo , Humanos , Molécula 1 de Adhesión Intercelular/química
2.
Prep Biochem Biotechnol ; 50(8): 820-826, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32282271

RESUMEN

Glucansucrases (GTFs) catalyzes the synthesis of α-glucans from sucrose and oligosaccharides in the presence of an acceptor sugar by transferring glucosyl units to the acceptor molecule with different linkages. The acceptor reactions can be affected by several parameters and this study aimed to determine the optimal reaction parameters for the production of glucansucrase-based oligosaccharides using sucrose and maltose as the donor and acceptor sugars, respectively via a hybrid technique of Response Surface Method (RSM) and Particle Swarm Optimization (PSO). The experimental design was performed using Central Composite Design and the tested parameters were enzyme concentration, acceptor:donor ratio and the reaction period. The optimization studies showed that enzyme concentration was the most effective parameter for the final oligosaccharides yields. The optimal values of the significant parameters determined for enzyme concentration and acceptor:donor ratio were 3.45 U and 0.62, respectively. Even the response surface plots for input parameters verified the PSO results, an experimental validation study was performed for the reverification. The experimental verification results obtained were also consistent with the PSO results. These findings will help our understanding in the role of different parameters for the production of oligosaccharides in the acceptor reactions of GTFs.


Asunto(s)
Glicosiltransferasas/metabolismo , Limosilactobacillus reuteri/enzimología , Oligosacáridos/metabolismo , Biocatálisis , Escherichia coli/genética , Escherichia coli/metabolismo , Glicosiltransferasas/genética , Microbiología Industrial , Limosilactobacillus reuteri/genética , Limosilactobacillus reuteri/metabolismo , Maltosa/metabolismo , Modelos Biológicos , Sacarosa/metabolismo
3.
Anal Biochem ; 556: 91-98, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29964028

RESUMEN

Pneumococci are one of the leading causes of infections throughout the world causing problems mainly in children, elderly, and immune-deficient patients. In recent years antibiotic resistant Streptococcus pneumoniae strains become widespread. Therefore simple, rapid, and specific detection methods are needed for public health. In this study, DNA aptamer probes against S. pneumoniae were selected using bacterial Systematic Evolution of Ligands by Exponential Enrichment (SELEX) and these probes were integrated in to a graphene oxide (GO) based fluorescent assay. Among the tested aptamers three candidates Lyd-1, Lyd-2 and Lyd-3 showed Kd values of 844.7 ±â€¯123.6, 1984.8 ±â€¯347.5, and 661.8 ±â€¯111.3 nM, respectively. These candidates showed binding affinity to S. pneumoniae and no specific binding to the bacteria used in negative selection. The binding of aptamers were showed by fluorescence spectroscopy and flow cytometry. GO based label-free fluorescent assay developed using Lyd-3 aptamer had a unique detection limit of 15 cfu mL-1. Thus we believe that the selected aptamers and fabricated GO based assay has potential to be used in the detection of S. pneumoniae. Selected aptamers selectively bind to S. pneumonia with anti-pneumococcal potential and holds great potential to be used as molecular probes for identifying and targeting.


Asunto(s)
Aptámeros de Nucleótidos/química , Grafito/química , Sondas Moleculares/química , Streptococcus pneumoniae , Citometría de Flujo , Humanos , Técnica SELEX de Producción de Aptámeros , Espectrometría de Fluorescencia
4.
J Craniofac Surg ; 29(5): e449-e454, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29521769

RESUMEN

PURPOSE: The purpose of this study is to suggest a patient-specific osteotomy line to optimize the distractor position and thus to minimize the disadvantages of conventional mandibular distraction osteogenesis (MDO) protocols. In addition, this study also aims to compare the conventional MDO protocols with the new MDO protocol proposed in this study in terms of both orthodontic outcomes and mechanical effects of osteotomy level on callus stabilization by means of the finite element method. METHODS: A preoperative patient-specific 3-dimensional bone model was created and segmented by using computed tomography images of an individual patient. Virtual orthodontic set-up was applied to the segmented model prior to the virtual surgery. In order to compare the proposed osteotomy line with the conventional lines used in clinical applications, virtual surgery simulations were performed and callus tissues were modelled for each scenario. The comparison of the success of each osteotomy line was carried out based on the occlusion of the teeth. RESULTS: The osteotomy line determined using the method proposed in this study has resulted in far less malocclusion than the conventional method. Namely, any angular deviation from the optimum osteotomy line determined in this study might result in deep-bite or open-bite. On the other hand, the finite element analysis results have indicated that this deviation also negatively affects the callus stability. CONCLUSION: In order to achieve a better MDO treatment in terms of occlusion of the teeth and the callus stability, the location of the osteotomy line and the distractor position can be computationally determined. The results suggest that MDO protocol developed in this study might be used in clinic to achieve a better outcome from the MDO treatment.


Asunto(s)
Osteogénesis por Distracción/métodos , Osteotomía/métodos , Retrognatismo/cirugía , Callo Óseo/diagnóstico por imagen , Callo Óseo/fisiopatología , Simulación por Computador , Femenino , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional , Masculino , Modelos Dentales , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/fisiopatología , Retrognatismo/diagnóstico por imagen , Retrognatismo/fisiopatología , Tomografía Computarizada por Rayos X , Interfaz Usuario-Computador
5.
Gac Sanit ; 35 Suppl 2: S164-S167, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34929802

RESUMEN

OBJECTIVE: This morbidity rate has increased compared to the results of a survey in 2012, which were 16,110 cases of STDs, and 11,141 cases in 2010. This study aimed at determining the relationship between knowledge and personal hygiene and the incidence of sexually transmitted diseases in adolescents at the Community Health Center Talise, Palu. METHODS: This study utilized a case-control study design to assess the relationship between knowledge and personal hygiene and the occurrence of sexually transmitted diseases. There were 84 samples in this study involving 42 cases and 42 controls. Data collection was carried out using a questionnaire. RESULT: The variable of personal hygiene showed that the Chi-Square test results provided a value of p=0.016, which means that the difference between individual hygiene and the incidence of sexually transmitted diseases (STDs) in adolescents was significant (p<0.05). CONCLUSION: This study concludes that the OR calculation has a value of 4.6, which means that adolescents who have insufficient knowledge have 4.6 times greater risk of suffering from STDs than adolescents who had sufficient knowledge.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Enfermedades de Transmisión Sexual , Adolescente , Estudios de Casos y Controles , Centros Comunitarios de Salud , Humanos , Higiene , Conducta Sexual , Enfermedades de Transmisión Sexual/epidemiología
6.
Appl Biochem Biotechnol ; 190(4): 1484-1497, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31782087

RESUMEN

Here, new calixarene sulfonamide analogs were synthesized from the reaction of chlorosulfonated calix[n]arene (n: 4, 6, and 8) with N,N'-dimethylethylenediamine or ethylenediamine for the first time and an excellent calixarene sulfonamide analog showing potent and selective cytotoxic activity on some cancer cell lines were discovered. Cytotoxicity of the prepared calix[n]arene sulfonamide analogs towards both cancer and healthy cell lines was assessed by performing cell growth inhibition assays. In cytotoxicity assay results, it was observed that while sulfonamide analog based calix[4]arene (9) was not affecting the growth of epithelial cell lines (HEK), and it was especially effective on inhibiting the growth of some human cancer cell lines (MCF-7 and MIA PaCa-2). These results highlight that sulfonamide analog-based calix [4] arene (9) can be further studied as a potential anticancer agent.


Asunto(s)
Antineoplásicos/farmacología , Calixarenos/farmacología , Sulfonamidas/farmacología , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HEK293 , Humanos , Concentración 50 Inhibidora , Células MCF-7 , Espectroscopía de Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier , Esferoides Celulares , Sulfonas/química , Ácido Trifluoroacético/química
7.
Microbiol Resour Announc ; 9(5)2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32001560

RESUMEN

Streptomyces spp. are bacteria that are responsible for the degradation of aromatic compounds and produce secondary metabolites. Here, we present a complete genome sequence of Streptomyces sp. strain S6, which was isolated from an oil palm plantation, with a 7.8-Mbp liner chromosome, a GC content of 72%, and 4,266 coding sequences.

8.
J Biosci ; 43(1): 97-104, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29485118

RESUMEN

Targeted drug delivery approaches have been implementing significant therapeutic gain for cancer treatment since last decades. Aptamers are one of the mostly used and highly selective targeting agents for cancer cells. Herein, we address a nano-sized targeted drug delivery approach adorned with A-172 glioblastoma cell-line-specific single stranded DNA (ssDNA) aptamer in which the chemotherapeutic agent Doxorubicin (DOX) had been conjugated. DNA aptamer, GMT-3, was previously selected for specific recognition of glioblastoma and represented many advantageous characteristics for drug targeting purposes. Flow cytometry analysis proved the binding efficiency of the specific aptamer to tumour cell lines. Celltype- specific toxicity of GMT-3:DOX complex was showed by XTT assay and terminated cytotoxic effects were screened for both target cell and a control breast cancer cell line. The result of this contribution demonstrated the potential utility of GMT-3 aptamer-mediated therapeutic drug transportation in the treatment of gliomas specifically. It was concluded that aptamer-mediated drug delivery can be applied successfully for clinical use.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Aptámeros de Nucleótidos/química , ADN de Cadena Simple/química , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Neuroglía/efectos de los fármacos , Antibióticos Antineoplásicos/química , Aptámeros de Nucleótidos/metabolismo , Transporte Biológico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN de Cadena Simple/metabolismo , Doxorrubicina/química , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Humanos , Glándulas Mamarias Humanas/efectos de los fármacos , Glándulas Mamarias Humanas/metabolismo , Glándulas Mamarias Humanas/patología , Neuroglía/metabolismo , Neuroglía/patología , Especificidad de Órganos
9.
Gac. sanit. (Barc., Ed. impr.) ; 35(supl. 2): S164-S167, 2021. tab
Artículo en Inglés | IBECS (España) | ID: ibc-220838

RESUMEN

Objective: This morbidity rate has increased compared to the results of a survey in 2012, which were 16,110 cases of STDs, and 11,141 cases in 2010. This study aimed at determining the relationship between knowledge and personal hygiene and the incidence of sexually transmitted diseases in adolescents at the Community Health Center Talise, Palu. Methods: This study utilized a case–control study design to assess the relationship between knowledge and personal hygiene and the occurrence of sexually transmitted diseases. There were 84 samples in this study involving 42 cases and 42 controls. Data collection was carried out using a questionnaire. Result: The variable of personal hygiene showed that the Chi-Square test results provided a value of p = 0.016, which means that the difference between individual hygiene and the incidence of sexually transmitted diseases (STDs) in adolescents was significant (p < 0.05). Conclusion: This study concludes that the OR calculation has a value of 4.6, which means that adolescents who have insufficient knowledge have 4.6 times greater risk of suffering from STDs than adolescents who had sufficient knowledge. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Conocimientos, Actitudes y Práctica en Salud , Enfermedades de Transmisión Sexual/epidemiología , Indonesia , Estudios de Casos y Controles , Centros Comunitarios de Salud , Conducta Sexual , Higiene
10.
Curr Top Med Chem ; 15(12): 1125-37, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25866272

RESUMEN

Aptamers have been increasingly applied in biomedical field as a class of biorecognition elements that possess many advantages such as high specificity and binding affinity, easy synthesis, easy modification, small size, non-toxicity and good stability. Many diseases like cancer exhibit cellular aberrations at morphological and molecular levels. Medical diagnosis based on molecular features can be highly specific and extremely sensitive when proper recognition molecule and an efficient signal transduction system are employed. However, bioanalysis of human diseases at the molecular level is an extremely challenging field because effective probes to identify and recognize biomarkers of diseases are not readily available. Traditional bio-recognition molecule, antibody has been exploited to develop excellent diagnosis assays in many formats, but antibodies are insufficient to match the requirements of fast and portable biosensors for point-of-care applications, which are at high demand in pathogenic bacteria detection as well as other diseases like cancer. Aptamers are short single-stranded oligonucleotides, which can be selected from random combinatorial library by SELEX in vitro. This relatively new biorecognition agent has superior intrinsic characteristics for biosensor development. In this review, we first present major aptamer selection technologies and the main formats of biosensors, which were frequently employed in aptasensor development. Then, the current state of aptamers as applied to medical diagnosis was discussed for specifically cancer and pathogen diagnosis. Finally, an overview of aptamer-nanomaterials conjugates was presented in many applications such as diagnosis, bioimaging, and theranostics.


Asunto(s)
Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Grampositivas/diagnóstico , Terapia Molecular Dirigida/métodos , Neoplasias/diagnóstico , Técnica SELEX de Producción de Aptámeros/métodos , Nanomedicina Teranóstica/métodos , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/uso terapéutico , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Péptidos de Penetración Celular/química , Péptidos de Penetración Celular/uso terapéutico , Diagnóstico por Imagen/métodos , Sistemas de Liberación de Medicamentos/métodos , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Neoplasias/patología , Neoplasias/terapia
11.
ACS Appl Mater Interfaces ; 4(6): 3007-11, 2012 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-22650355

RESUMEN

In this work, gold nanoparticles perform Boolean logic operations in response to two proangiogenic targets important in cancer diagnosis and treatment: PDGF and VEGF. In the absence of protein target, gold nanoparticles are initially dispersed as a red solution; the addition of target proteins causes nanoparticle aggregation, turning the solution blue, as well as the release of dye-labeled aptamer probes, which causes an increase in fluorescence. These outputs constitute an AND or OR gate for simultaneous protein detection. We believe this logic-gate-based detection system will become the basis for novel rapid, cheap, and reliable sensors for diagnostic applications.

12.
ACS Chem Neurosci ; 2(3): 175-181, 2011 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-21892384

RESUMEN

Aptamer probes for specific recognition of glioblastoma multiforme were generated using a repetitive and broad cell-SELEX-based procedure without negative selection. The 454 sequencing technology was used to monitor SELEX, and bioinformatics tools were used to identify aptamers from high throughput data. A group of aptamers were generated that can bind to target cells specifically with dissociation constants (K(d)) in the nanomolar range. Selected aptamers showed high affinity to different types of glioblastoma cell lines, while showing little or no affinity to other cancer cell lines. The aptamers generated in this study have potential use in different applications, such as probes for diagnosis and devices for targeted drug delivery, as well as tools for molecular marker discovery for glioblastomas.

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