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1.
Anal Bioanal Chem ; 412(14): 3373-3381, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32072206

RESUMEN

An optical biosensor module for soil contamination assessment is presented, employing bioluminescent bacterial bioreporters encapsulated in poly-dopamine (PD)-coated alginate microbeads. The PD-coated beads displayed improved mechanical strength and stability, but somewhat delayed responses to the inducing toxicant. Using toluene as a model soil contaminant, two bioluminescent reporter strains were employed for its detection in the ambient light-blocking, temperature-controlled biosensor module. Bioluminescence of strain TV1061 (harboring an inducible grpE::luxCDABE fusion) increased and that of strain GC2 (harboring a constitutive lac::luxCDABE fusion) decreased in the presence of increasing toluene concentrations. In the former case, a maximal effect was observed in the presence of 1% toluene. This simple optical detection biosensor module may potentially be utilized for monitoring soil contamination from areas suspected of chemical pollution such petrochemical industrial zones or petrol stations.


Asunto(s)
Técnicas Biosensibles/instrumentación , Monitoreo del Ambiente/instrumentación , Contaminantes del Suelo/análisis , Suelo/química , Tolueno/análisis , Bacterias/citología , Bacterias/metabolismo , Células Inmovilizadas/citología , Células Inmovilizadas/metabolismo , Diseño de Equipo , Mediciones Luminiscentes/instrumentación , Contaminantes del Suelo/metabolismo , Tolueno/metabolismo
2.
Analyst ; 140(19): 6671-5, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26334055

RESUMEN

We present a novel reflectance-based colorimetric aptasensor using gold nanoparticles for the detection of oxytetracycline for the first time. It was found that the reflectance-based measurement at two wavelengths (650 and 520 nm) can generate more stable and sensitive signals than absorbance-based sensors to determine the aggregation of AuNPs, even at high AuNP concentrations. One of the most common antibacterial agents, oxytetracycline (OTC), was detected at concentrations as low as 1 nM in both buffer solution and tap water, which was 25-fold more sensitive, compared to the previous absorbance-based colorimetric aptasensors. This reflectance-based colorimetric aptasensor using gold nanoparticles is considered to be a better platform for portable sensing of small molecules using aptamers.


Asunto(s)
Antibacterianos/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Oro/química , Nanopartículas del Metal/química , Oxitetraciclina/análisis , Antibacterianos/química , Aptámeros de Nucleótidos/genética , Secuencia de Bases , Colorimetría , Límite de Detección , Oxitetraciclina/química
3.
Analyst ; 139(18): 4696-701, 2014 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-25057512

RESUMEN

The use of genetically engineered bioluminescent bacteria, in which bioluminescence is induced by different modes of toxic action, represents an alternative to acute toxicity tests using living aquatic organisms (plants, vertebrates, or invertebrates) in an aqueous environment. A number of these bacterial strains have been developed, but there have been no attempts to develop a hand-held type of biosensor for monitoring or identification of toxicity. We report a facile dip-stick type biosensor using genetically engineered bioluminescent bacteria as a new platform for classification and identification of toxicity in water environments. This dip-stick type biosensor is composed of eight different optically color-coded functional alginate beads that each encapsulates a different bioluminescent bacterial strain and its corresponding fluorescent microbead. These color-coded microbeads exhibit easy identification of encapsulated microbeads, since each microbead has a different color code depending on the bioluminescent bacterial strain contained and improved cell-stability compared to liquid culture. This dip-stick type biosensor can discriminate different modes of toxic actions (i.e. DNA damage, oxidative damage, cell-membrane damage, or protein damage) of sample water tested by simply dipping the stick into the water samples. It was found that each color-coded microbead emitted distinct bioluminescence, and each dip-stick type biosensor showed different bioluminescence patterns within 2 hours, depending on the toxic chemicals contained in LB medium, tap water, or river water samples. This dip-stick type biosensor can, therefore, be widely and practically used in checking toxicity of water in the environment primarily in situ, possibly indicating the status of biodiversity.


Asunto(s)
Alginatos/química , Técnicas Biosensibles/instrumentación , Monitoreo del Ambiente/instrumentación , Photorhabdus/metabolismo , Vibrio/metabolismo , Contaminantes Químicos del Agua/análisis , Agua Potable/análisis , Diseño de Equipo , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Mediciones Luminiscentes/instrumentación , Photorhabdus/efectos de los fármacos , Ríos/química , Vibrio/efectos de los fármacos , Agua/análisis , Contaminantes Químicos del Agua/metabolismo
4.
Biosens Bioelectron ; 246: 115843, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38006700

RESUMEN

Aptamers are a versatile class of receptors with a high affinity and selectivity for specific targets. Although their ability to recognize individual targets has been extensively studied, some scenarios require the development of receptors capable of identifying all target groups. This study investigated the use of aptamers to achieve the broad-spectrum recognition of groups instead of individual targets. Aptamers were screened for selectively distinct groups of Cronobacter species associated with foodborne diseases. Seven Cronobacter spp. were divided into Group A (C. sakazakii, C. malonaticus, C. turicensis, and C. muytjensii) and Group B (C. dublinensis, C. condimenti, and C. universalis). Aptamers with exclusive selectivity for each group were identified, allowing binding to the species within their designated group while excluding those from the other group. The screened aptamers demonstrated reliable affinity and specificity with dissociation constants ranging from 1.3 to 399.7 nM for Group A and 4.0-24.5 nM for Group B. These aptamers have also been successfully employed as receptors in an electrochemical biosensor platform, enabling the selective detection of each group based on the corresponding aptamer (limit of detection was 7.8 and 3.2 CFU for Group A and Group B, respectively). The electrochemical sensor effectively detected the extent of infection in each group in powdered infant formula samples. This study highlights the successful screening and application of group-selective aptamers as sensing receptors, emphasizing their potential for diverse applications in different fields such as food safety, environmental monitoring, and clinical diagnostics, where the selective biosensing of target groups is crucial.


Asunto(s)
Técnicas Biosensibles , Cronobacter sakazakii , Cronobacter , Humanos , Lactante , Oligonucleótidos , Fórmulas Infantiles
5.
Biosens Bioelectron ; 251: 116097, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38330774

RESUMEN

Severe periodontitis affects nearly 1 billion individuals worldwide, highlighting the need for early diagnosis. Here, an integrated system consisting of a microfluidic chip and a portable point-of-care (POC) diagnostic device is developed using a polymethyl methacrylate (PMMA) chip fabrication and a three-dimensional printing technique, which is automatically controlled by a custom-designed smartphone application to routinely assess the presence of a specific periodontitis biomarker, odontogenic ameloblast-associated protein (ODAM). A sandwich-type fluorescence aptasensor is developed on a microfluidic chip, utilizing aptamer pair (MB@OD64 and OD35@FAM) selectively binding to target ODAM. Then this microfluidic chip is integrated into an automated Internet of Things (IoT)-based POC device, where fluorescence intensity, as a signal, from the secondary aptamer binding to ODAM in a sandwich-type binding reaction on the microfluidic chip is measured by a complementary metal oxide semiconductor (CMOS) camera with a 488 nm light-emitting diode (LED) excitation source. Obtained signals are processed by a microprocessor and visualized on a wirelessly connected smartphone application. This integrated biosensor system allows the rapid and accurate detection of ODAM within 30 min with a remarkable limit of detection (LOD) of 0.011 nM under buffer conditions. Clinical application is demonstrated by successfully distinguishing between low-risk and high-risk individuals with 100 % specificity. A strong potential in the translation of this fluorescence-based microfluidic aptasensor integrated with an IoT-based POC system is expected to be employed for non-invasive, on-site, rapid, and accurate ODAM detection, facilitating periodontitis diagnosis.


Asunto(s)
Técnicas Biosensibles , Internet de las Cosas , Enfermedades Periodontales , Periodontitis , Humanos , Enfermedades Periodontales/diagnóstico , Periodontitis/metabolismo , Proteínas
6.
Sci Rep ; 14(1): 7997, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580756

RESUMEN

Hepatocellular carcinoma (HCC) is characterized by high incidence and fatality rates worldwide. In our exploration of prognostic factors in HCC, the 26s proteasome subunit, non-ATPase 1 (PSMD1) protein emerged as a significant contributor, demonstrating its potential as a therapeutic target in this aggressive cancer. PSMD1 is a subunit of the 19S regulatory particle in the 26S proteasome complex; the 19S particle controls the deubiquitination of ubiquitinated proteins, which are then degraded by the proteolytic activity of the complex. Proteasome-targeting in cancer therapy has received significant attention because of its practical application as an established anticancer agent. We investigated whether PSMD1 plays a critical role in cancer owing to its prognostic significance. PSMD1 depletion induced cell cycle arrest in G2/M phase, DNA damage and apoptosis of cancer cells, irrespective of the p53 status. PSMD1 depletion-mediated cell death was accompanied by an increase in overall protein ubiquitination. These phenotypes occurred exclusively in cancer cells, with no effects observed in normal cells. These findings indicate that PSMD1 depletion-mediated ubiquitination of cellular proteins induces cell cycle arrest and eventual death in cancer cells, emphasizing PSMD1 as a potential therapeutic target in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Apoptosis/genética , Carcinoma Hepatocelular/genética , Daño del ADN , Neoplasias Hepáticas/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitinación
7.
Anal Chem ; 85(1): 66-74, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23198789

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) causes porcine reproductive and respiratory syndrome disease (PRRS), a disease that has a significant and economic impact on the swine industry. In this study, single-stranded DNA (ssDNA) aptamers with high specificity and affinity against VR-2332 strain of PRRSV type II were successfully obtained. Of 19 candidates, the LB32 aptamer was found to be the most specific and sensitive to VR-2332 strain according to an aptamer-based surface plasmon resonance (SPR) analysis. The detection of VR-2332 of PRRSV type II was successfully accomplished using the enzyme-linked antibody-aptamer sandwich (ELAAS) method. The detection limit of ELAAS was 4.8 × 10(0) TCID(50)/mL that is comparable to some of the previous reports of the PCR-based detection but does not require any complicated equipment or extra costs. Moreover, this ELAAS-based PRRSV detection showed similar sensitivity for both the VR-2332 samples spiked in diluted swine serum and in buffer. Therefore, this VR-2332 strain-specific aptamer and its assay method with high specificity can be used as an alternative method for the fast and precise detection of PRRSV.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas de Inmunoadsorción , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , ARN Viral/análisis , Animales , Anticuerpos Monoclonales/inmunología , Secuencia de Bases , ADN de Cadena Simple/química , Técnicas de Inmunoadsorción/instrumentación , Síndrome Respiratorio y de la Reproducción Porcina/diagnóstico , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/aislamiento & purificación , ARN Viral/sangre , Resonancia por Plasmón de Superficie , Porcinos
8.
Bioprocess Biosyst Eng ; 36(12): 1923-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23689757

RESUMEN

The development and implementation of strategies for CO2 mitigation are necessary to counteract the greenhouse gas effect of carbon dioxide emissions. To demonstrate the possibility of simultaneously capturing CO2 and utilizing four-carbon compounds, an integrated system using CA and PEPCase was developed, which mimics an in vivo carbon dioxide concentration mechanism. We first cloned the PEPCase 1 gene of the marine diatom Phaeodactylum tricornutum and produced a recombinant PtPEPCase 1. The affinity column purified PtPEPCase 1 exhibited specific enzymatic activity (5.89 U/mg). When the simultaneous and coordinated reactions of CA from Dunaliella sp. and the PtPEPCase 1 occurred, more OAA was produced than when only PEPCase was present. Therefore, this integrated CA-PEPCase system can be used not only to capture CO2 but also for a new technology to produce value-added four-carbon platform chemicals.


Asunto(s)
Dióxido de Carbono/metabolismo , Anhidrasas Carbónicas/metabolismo , Diatomeas/enzimología , Ácido Oxaloacético/metabolismo , Fosfoenolpiruvato Carboxilasa/metabolismo , Western Blotting , Anhidrasas Carbónicas/genética , Sistema Libre de Células , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Vectores Genéticos , Fosfoenolpiruvato Carboxilasa/genética
9.
Biosens Bioelectron ; 228: 115199, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36906992

RESUMEN

In this study, we aimed to introduce a new electrochemical aptasensor based on the tyramide signal amplification (TSA) technology for a highly-sensitive detection of the pathogenic bacterium, Staphylococcus aureus, as a model of foodborne pathogens. In this aptasensor, the primary aptamer, SA37, was used to specifically capture bacterial cells; the secondary aptamer, SA81@HRP, was used as the catalytic probe; and a TSA-based signal enhancement system comprising of biotinyl-tyramide and streptavidin-HRP as electrocatalytic signal tags was adopted to fabricate the sensor and improve the detection sensitivity. S. aureus cells were selected as the pathogenic bacteria to verify the analytical performance of this TSA-based signal-enhancement electrochemical aptasensor platform. After the simultaneous binding of SA37-S. aureus-SA81@HRP formed on the gold electrode, thousands of @HRP molecules could be bound onto the biotynyl tyramide (TB) displayed on the bacterial cell surface through a catalytic reaction between HRP and H2O2, resulting in the generation of the highly amplified signals mediated by HRP reactions. This developed aptasensor could detect S. aureus bacterial cells at an ultra-low concentration, with a limit of detection (LOD) of 3 CFU/mL in buffer. Furthermore, this chronoamperometry aptasensor successfully detected target cells in both tap water and beef broth with LOD to be 8 CFU/mL, which are very high sensitivity and specificity. Overall, this electrochemical aptasensor using TSA-based signal-enhancement could be a very useful tool for the ultrasensitive detection of foodborne pathogens in food and water safety and environmental monitoring.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Animales , Bovinos , Staphylococcus aureus , Aptámeros de Nucleótidos/química , Técnicas Electroquímicas/métodos , Nanopartículas del Metal/química , Peróxido de Hidrógeno/química , Técnicas Biosensibles/métodos , Oro/química , Límite de Detección
10.
Trends Biotechnol ; 41(3): 374-395, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36567185

RESUMEN

Biosensors are utilized in several different fields, including medicine, food, and the environment; in this review, we examine recent developments in biosensors for healthcare. These involve three distinct types of biosensor: biosensors for in vitro diagnosis with blood, saliva, or urine samples; continuous monitoring biosensors (CMBs); and wearable biosensors. Biosensors for in vitro diagnosis have seen a significant expansion recently, with newly reported clustered regularly interspaced short palindromic repeats (CRISPR)/Cas methodologies and improvements to many established integrated biosensor devices, including lateral flow assays (LFAs) and microfluidic/electrochemical paper-based analytical devices (µPADs/ePADs). We conclude with a discussion of two novel groups of biosensors that have drawn great attention recently, continuous monitoring and wearable biosensors, as well as with perspectives on the commercialization and future of biosensors.


Asunto(s)
Técnicas Biosensibles , Medicina , Dispositivos Laboratorio en un Chip , Atención a la Salud
11.
Sci Rep ; 13(1): 5658, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-37024561

RESUMEN

To identify potential plasma biomarkers associated with microbial invasion of the amniotic cavity (MIAC) and/or intraamniotic inflammation (IAI) in women with preterm premature rupture of membranes (PPROM). This retrospective cohort study included 182 singleton pregnant women with PPROM (23-33 weeks) who underwent amniocentesis. Plasma samples; all subjects were chosen from these participants and were analyzed using label-free liquid chromatography-tandem mass spectrometry for proteome profiling using a nested case-control study design (cases with MIAC/IAI vs. non-MIAC/IAI controls [n = 9 each]). Three identified target molecules for MIAC/IAI were further verified by ELISA in the study cohort (n = 182). Shotgun proteomic analysis revealed 17 differentially expressed proteins (P < 0.05) in the plasma of MIAC/IAI cases. In particular, the levels of FCGR3A and haptoglobin, but not LRP1, were found to be increased in the plasma of patients with MIAC, IAI, and both MIAC/IAI compared with those without these conditions. Moreover, these differences remained significant after adjusting for gestational age at sampling. The area under the curves of plasma FCGR3A and haptoglobin ranged within 0.59-0.65 with respect to each of the three outcome measures. Plasma FCGR3A and haptoglobin were identified as potential independent biomarkers for less-invasively detecting MIAC/IAI in women with PPROM.


Asunto(s)
Corioamnionitis , Recién Nacido , Femenino , Humanos , Embarazo , Corioamnionitis/diagnóstico , Corioamnionitis/metabolismo , Estudios de Casos y Controles , Estudios Retrospectivos , Haptoglobinas/metabolismo , Proteómica , Líquido Amniótico/metabolismo , Biomarcadores/metabolismo , Inflamación/metabolismo , Edad Gestacional
12.
Sci Rep ; 13(1): 2869, 2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36804462

RESUMEN

Although biomarker candidates associated with psoriasis have been suggested, those for predicting the risk of cardiovascular disease (CVD) early in patients with psoriasis are lacking. We aimed to identify candidate biomarkers that can predict the occurrence of CVD in psoriasis patients. We pursued quantitative proteomic analysis of serum samples composed of three groups: psoriasis patients with and those without CVD risk factors, and healthy controls. Age/Sex-matched serum samples were selected and labeled with 16-plex tandem mass tag (TMT) and analyzed using liquid chromatography-mass spectrometry and subsequent verification with ELISA. Of the 184 proteins that showed statistical significance (P-value < 0.05) among the three groups according to TMT-based quantitative analysis, 98 proteins showed significant differences (> 2.0-fold) between the psoriasis groups with and without CVD risk factors. Verification by ELISA revealed that caldesmon (CALD1), myeloid cell nuclear differentiation antigen (MNDA), and zyxin (ZYX) levels were significantly increased in the psoriasis group with CVD risk factors. Further network analysis identified pathways including integrin signaling, which could be related to platelet aggregation, and actin cytoskeleton signaling. Three novel candidates (MNDA, ZYX, and CALD1) could be potential biomarkers for predicting CVD risks in psoriasis patients. We expect these biomarker candidates can be used to predict CVD risk in psoriasis patients in clinical settings although further studies including large validation are needed.


Asunto(s)
Enfermedades Cardiovasculares , Psoriasis , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/etiología , Proteómica/métodos , Factores de Riesgo , Psoriasis/complicaciones , Biomarcadores , Factores de Riesgo de Enfermedad Cardiaca
13.
Ecotoxicol Environ Saf ; 78: 239-45, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22154143

RESUMEN

The chronic toxicity test has been conducted for twenty-eight days to characterize the hepatic expression levels of eight stress-related genes after exposing Medaka to two doses of silver nitrate or a silver nanoparticle (Ag-NP) using real time RT-PCR analysis. This extends our previously published work to include three additional biomarkers and three later time points. In comparing with the control, the significant induction of MT and GST genes in livers of the fish exposed to 1 µg/l Ag-NPs was observed at various time points during the test period. The Orla C3-1 (Medaka) gene was slightly induced only with 1 µg/l Ag-NPs at 7-day exposure while the suppression of p53 and HSP70 was recorded in all exposures at the end of the test. The gene encoding transferrin was repressed at day 21 by both silver types and at every exposure dosage. These results revealed that the Ag-NPs increase metal detoxification, oxidative and inflammatory stress, and finally stimulate immune responses in Medaka. The conspicuous induction of choriogenin L and vitellogenin 1 in male fish exposed to Ag-NPs, especially at 7- and 21-day, compared with the exposures of AgNO(3) or control was the first attempt to examine estrogenic effects of Ag-NPs.


Asunto(s)
Expresión Génica/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Plata/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/metabolismo , Estrógenos/toxicidad , Hígado/metabolismo , Masculino , Oryzias/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vitelogeninas/genética , Vitelogeninas/metabolismo
14.
Biosens Bioelectron ; 198: 113835, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34847360

RESUMEN

A pair of aptamers for Staphylococcus aureus (S. aureus) is immensely needed for developing sandwich-type signal-on electrochemical aptasensors. In this study, we have successfully developed a cognate pair of aptamers that bind to S. aureus simultaneously, among many aptamer candidates screened out after a total of ten rounds of bacterial cell-based systemic evolution of ligands by exponential enrichment (SELEX). The obtained aptamer candidates have been estimated by using flow cytometry and confocal microscope, to evaluate their binding affinity and specificity to the target cells. The screening for sandwich-type binding of cognate pair of aptamers with S. aureus was conducted by enzyme-based colorimetric assay and confirmed by circular dichroism (CD), two-color fluorescence imaging analysis, additionally. The cognate pair of two aptamers, named SA37 and SA81, showed very good affinity and specificity to S. aureus with their dissociation constants (Kd) of 16.5 ± 3.4 nM and 14.47 ± 8.18 nM, respectively. These newly discovered cognate pair of aptamers have been very successfully implemented to develop a sandwich-type signal-on electrochemical biosensor with the limit of detection (LOD) of 39 CFUs and 414 CFUs in buffer and spiked tap water samples, respectively. This study showed that this cognate pair of aptamers-based detection of S. aureus enables simple, rapid, and robust biosensors for food safety management.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Infecciones Estafilocócicas , Humanos , Límite de Detección , Técnica SELEX de Producción de Aptámeros , Staphylococcus aureus
15.
Biosens Bioelectron ; 199: 113884, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34942544

RESUMEN

Recently, point-of-care tests (POCT) have gained much attention due to their convenient, fast, simple, and easy characteristics. For POCT, portability is an essential feature. In this study, we have successfully fabricated a portable mini-potentiostat. Using chronoamperometry, electrical signals of this portable mini-potentiostat were measured, and the analytical performance of electrochemical aptasensors was compared with a benchtop potentiostat. The electrochemical signals measured by mini-potentiostat can be displayed on the screen of a smartphone. To verify the analytical performance of this portable electrochemical aptasensor platform with a mini-potentiostat, two well-known model protein biomarkers, vaspin, a type 2 diabetes biomarker, and thrombin, a biomarker for pulmonary metastasis and cardiovascular disease, were confirmed to be detected by using corresponding aptamer duo. After solid verification of this portable electrochemical aptasensor platform, we have successfully implemented this portable mini-potentiostat system to develop a portable sandwich-type binding pair of aptamers-based electrochemical biosensor, which can diagnose periodontal disease by measuring ODAM biomarker. The linear range of this ODAM biosensor was 0 to 15 nM with a detection limit of 0.02 nM and 1 nM in buffer and saliva, respectively. The sensitivity of this biosensor has been greatly enhanced, compared to previously developed surface plasmon resonance (SPR) or lateral flow assay (LFA) based aptasensors. This study showed that this new portable aptamer duo-based biosensor is expected to diagnose the early stage of periodontal diseases from real samples, such as saliva or gingival crevicular fluid in a short time as a point-of-care (POC) testing.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Diabetes Mellitus Tipo 2 , Enfermedades Periodontales , Diagnóstico Precoz , Técnicas Electroquímicas , Humanos , Límite de Detección , Enfermedades Periodontales/diagnóstico
16.
Biomaterials ; 286: 121578, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35594838

RESUMEN

Activation state of synovial macrophages is significantly correlated with disease activity and severity of rheumatoid arthritis (RA) and provides valuable clues for RA treatment. Classically activated M1 macrophages in inflamed synovial joints secrete high levels of pro-inflammatory cytokines and chemokines, resulting in bone erosion and cartilage degradation. Herein, we propose extracellular vesicle (EV)-guided in situ macrophage reprogramming toward anti-inflammatory M2 macrophages as a novel RA treatment modality based on the immunotherapeutic concept of reestablishing M1-M2 macrophage equilibrium in synovial tissue. M2 macrophage-derived EVs (M2-EVs) were able to convert activated M1 into reprogrammed M2 (RM2) macrophages with extremely high efficiency (>90%), producing a distinct protein expression pattern characteristic of anti-inflammatory M2 macrophages. In particular, M2-EVs were enriched for proteins known to be involved in the generation and migration of M2 macrophages as well as macrophage reprogramming factors, allowing for rapid and efficient driving of macrophage polarization toward M2 phenotype. After administration of M2-EVs into the joint of a collagen-induced arthritis mouse model, the synovial macrophage polarization was significantly shifted from M1 to M2 phenotype, a process that benefited greatly from the long residence time (>3 days) of M2-EVs in the joint. This superb in situ macrophage-reprogramming ability of EVs resulted in decreased joint swelling, arthritic index score and synovial inflammation, with corresponding reductions in bone erosion and articular cartilage damage and no systemic toxicity. The anti-RA effects of M2-EVs were comparable to those of the conventional disease-modifying antirheumatic drug, Methotrexate, which causes a range of toxic adverse effects, including gastrointestinal mucosal injury. Overall, our EV-guided reprogramming strategy for in situ tuning of macrophage responses holds great promise for the development of anti-inflammatory therapeutics for the treatment of various inflammatory diseases in addition to RA.


Asunto(s)
Artritis Reumatoide , Vesículas Extracelulares , Animales , Artritis Reumatoide/tratamiento farmacológico , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo , Ratones , Membrana Sinovial/metabolismo
17.
ACS Sens ; 7(8): 2188-2197, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-35930745

RESUMEN

Accurate, onsite detection of pathogenic bacteria from food matrices is required to rapidly respond to pathogen outbreaks. However, accurately detecting whole-cell bacteria in large sample volumes without an enrichment step remains a challenge. Therefore, bacterial samples must be concentrated, identified, and quantified. We developed a tunable magnetic capturing cartridge (TMCC) and combined it with a portable digital fluorescence reader for quick, onsite, quantitative detection of Staphylococcus aureus. The TMCC platform integrates an absorption pad impregnated with water-soluble polyvinyl alcohol (PVA) with an injection-molded polycarbonate (PC) plate that has a hard magnet on its back and an acrylonitrile-butadiene-styrene case. An S. aureus-specific antibody conjugated with magnetic nanoparticles was used to concentrate bacteria from a large-volume sample and capture bacteria within the TMCC. The retention time for capturing bacteria on the TMCC was adjusted by controlling the concentration and volume of the PVA solution. Concentrated bacterial samples bound to target-specific aptamer probes conjugated with quantum dots were loaded into the TMCC for a controlled time, followed by attachment of the bacteria to the PC plate and removal of unbound aptamer probes with wash buffer. The captured bacteria were quantified using a digital fluorescence reader equipped with an embedded program that automatically counts fluorescently tagged bacteria. The bacterial count made using the TMCC was comparable to a standard plate count (R2 = 0.9898), with assay sensitivity and specificity of 94.3 and 100%, respectively.


Asunto(s)
Aptámeros de Nucleótidos , Infecciones Estafilocócicas , Bacterias , Humanos , Imagen Óptica , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus
18.
Dev Biol ; 339(1): 188-99, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20026026

RESUMEN

Having the ability to coordinate the behavior of stem cells to induce regeneration of specific large-scale structures would have far-reaching consequences in the treatment of degenerative diseases, acute injury, and aging. Thus, identifying and learning to manipulate the sequential steps that determine the fate of new tissue within the overall morphogenetic program of the organism is fundamental. We identified novel early signals, mediated by the central nervous system and 3 innexin proteins, which determine the fate and axial polarity of regenerated tissue in planarians. Modulation of gap junction-dependent and neural signals specifically induces ectopic anterior regeneration blastemas in posterior and lateral wounds. These ectopic anterior blastemas differentiate new brains that establish permanent primary axes re-established during subsequent rounds of unperturbed regeneration. These data reveal powerful novel controls of pattern formation and suggest a constructive model linking nervous inputs and polarity determination in early stages of regeneration.


Asunto(s)
Polaridad Celular , Conexinas/fisiología , Planarias/fisiología , Regeneración , Animales , Sistema Nervioso Central/embriología , Hibridación in Situ
19.
Macromol Rapid Commun ; 32(15): 1169-73, 2011 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-21748816

RESUMEN

Small, organic, toxic compounds are not well eliminated by water-treatment systems and eventually become concentrated in the human body. In this study, liposomes are employed to house aptamers with their own binding buffer. When small, organic, toxic compounds in water pass through a liposome barrier, only the target molecules are captured by the DNA aptamers inside the liposomes. The capture efficiency is not high when DNA aptamers are used in tap water. When DNA aptamers in liposomes are used, the capture efficiency increases more than 80%. The simultaneous and selective elimination of target toxicants is successfully performed for tap-water samples containing toxicant mixtures.


Asunto(s)
Aptámeros de Nucleótidos/química , Liposomas/química , Compuestos Orgánicos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Purificación del Agua/instrumentación
20.
Lab Chip ; 10(20): 2695-701, 2010 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-20664847

RESUMEN

We have successfully developed optically coded functional microbeads by co-encapsulating both bioluminescent reporter bacterial cells and fluorescent microspheres within a common alginate microbead. These microbeads harboring an individual self-identification code using fluorescent microspheres could be randomly scattered on any multi-well chip plate as long as the size of the microbeads are made to fit on it with the result that, since cell types are identified on the basis of fluorescent color, microbead arrays were fabricated without pre-designation of an individual well. As an example of this method, five different stress specific bioluminescent bacterial strains, each with a different optical code, were successfully implemented to make five different types of optically coded functional microbeads, with a speed of about 30 microbeads/min. Each functional microbead has a specific stress-specific bacterial strain and, as an identification optical code, one of five optical codes generated from fluorescence microspheres such as yellow, green, red, yellow + green, or no fluorescence. This final randomly scattered functional microbeads array biochip, with a fast fabrication of each chip at every 2 min, successfully demonstrated its ability in toxicity screening and monitoring for samples with a few examples for five different stress chemicals. This simple and fast, but not tedious and complicated procedure should be widely and practically used in making cell array chips for the monitoring of environmental toxicity, new-borne chemicals, pharmaceutical drugs and cosmic rays in the space station or spaceships in future.


Asunto(s)
Bioensayo/instrumentación , Citometría de Flujo/instrumentación , Análisis por Micromatrices/instrumentación , Técnicas Analíticas Microfluídicas/instrumentación , Dispositivos Ópticos , Espectrometría de Fluorescencia/instrumentación , Pruebas de Toxicidad/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Microesferas , Coloración y Etiquetado
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