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1.
J Food Sci Technol ; 61(4): 734-742, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38410263

RESUMEN

In this study, the effects of the ripening process and fruit powder addition on the physical, chemical, total phenolic content, antioxidant capacity, volatile compounds, and sensory properties of Kashar cheese were determined. Total phenol content, antioxidant capacity, volatile compounds, and fatty acid esters were determined by Folin Ciocalteu, DPPH, SPME, and GC-MS, GC-FID, respectively. Of the 27 fatty acids identified in cheeses, palmitic, oleic, myristic, and stearic acids were found to have the highest ratios, respectively. While the total amount of phenol substance was 144.44 mg GAE/L in fresh, it increased to 374.84 mg GAE/L with ripening and 520.26 mg GAE/L with ripening + plant. A total of 58 volatile compounds, including 14 alcohols, 10 acids, 9 ketones, 9 hydrocarbons, 7 esters, 7 aldehydes,and 2 sulfur compounds, were detected in cheese. Alcohol (27.20%) in fresh kashar, acid (61.40%) in ripened kashar, and ketone (43.73%) in ripened + plant kashar were the volatile compounds groups determined at the highest rate. The ripening process and plant addition did not contribute positively to the sensory properties of the cheeses.

2.
Cell Rep Med ; 4(10): 101198, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37716353

RESUMEN

The emerging field of liquid biopsy stands at the forefront of novel diagnostic strategies for cancer and other diseases. Liquid biopsy allows minimally invasive molecular characterization of cancers for diagnosis, patient stratification to therapy, and longitudinal monitoring. Liquid biopsy strategies include detection and monitoring of circulating tumor cells, cell-free DNA, and extracellular vesicles. In this review, we address the current understanding and the role of existing liquid-biopsy-based modalities in cancer diagnostics and monitoring. We specifically focus on the technical and clinical challenges associated with liquid biopsy and biomarker development being addressed by the Liquid Biopsy Consortium, established through the National Cancer Institute. The Liquid Biopsy Consortium has developed new methods/assays and validated existing methods/technologies to capture and characterize tumor-derived circulating cargo, as well as addressed existing challenges and provided recommendations for advancing biomarker assays.


Asunto(s)
Ácidos Nucleicos Libres de Células , Vesículas Extracelulares , Células Neoplásicas Circulantes , Humanos , Biopsia Líquida , Ácidos Nucleicos Libres de Células/genética , Biomarcadores , Células Neoplásicas Circulantes/patología
3.
PeerJ ; 11: e15526, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37361039

RESUMEN

The success of rose breeding programs is low due to poor seed sets and germination rates. Determining fertile parents and cross combinations that show high compatibility could increase the effectiveness of breeding programs. In this study, three rose varieties belonging to Rosa × hybrida (Jumilia, First Red and Magnum), and two old garden rose species (Black Rose and Cabbage Rose) with known ploidy levels were reciprocally crossbred under controlled conditions to determine the successful crosses by checking fertility. The pollen germination rate (PG), crossability rate (CR), seed number per fruit (SNpF), seed production efficiency (SPE), seed germination rate (SGR), fruit weight (FW), seed weight (SW) and stigma number (SiN), etc. were recorded. Comprehensive fertility index value was calculated. Principal component analysis (PCA), correlation matrix, and hierarchical heat map were used to evaluate the data. The findings showed that old garden roses had more viable pollen than hybrid tea roses. The crossing success improved as pollen fertility increased. Also, female parent fertility improved crossing success just as much as pollen fertility. Although the pollen fertility and stigma numbers were low, some combinations had higher CR and SPE. The maximum SPE (from 8.67% to 19.46%) was determined in combinations where Black Rose was the female parent despite the lower stigma number and low pollen fertility. The highest CR was recorded in Black Rose × First Red (94.36%). All combinations in which Black Rose was used as the female parent had a more stable CR. The SNpF of combinations where hybrid rose varieties were female parents and old garden roses were pollen parents was higher than other combinations where hybrid rose varieties were both female and pollen parents. The SPE in intraspecific crosses was lower than that obtained from interspecific crosses. Moreover, the SGR decreased in combinations that produced heavier seeds. The results suggested that SPE is a more accurate parameter than SNpF in demonstrating combination success in breeding programs. Black Rose × First Red, Black Rose × Jumilia, Black Rose × Magnum and Black Rose × Cabbage Rose combinations can be used successfully as the PCA and heat map showed. Black Rose showed better performance as both seed and pollen parents according to the comprehensive fertility index. From the correlation matrix, it is understood that the number of stigmas cannot be an important criterion in parent selection. Old garden roses can be used as parents to increase the success of breeding programs. However, it is necessary to reveal how successful they are in transferring desired characteristics such as scent, petal number, and color.


Asunto(s)
Rosa , Rosa/genética , Fitomejoramiento , Hibridación Genética , Fertilidad/genética ,
4.
World J Microbiol Biotechnol ; 39(5): 131, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36959476

RESUMEN

Biofilm is a complex consortium of microorganisms attached to biotic or abiotic surfaces and live in self-produced or acquired extracellular polymeric substances (EPSs). EPSs are mainly formed by lipids, polysaccharides, proteins, and extracellular DNAs. The adherence to the surface of microbial communities is seen in food, medical, dental, industrial, and environmental fields. Biofilm development in food processing areas challenges food hygiene, and human health. In addition, bacterial attachment and biofilm formation on medical implants inside human tissue can cause multiple critical chronic infections. More than 30 years of international research on the mechanisms of biofilm formation have been underway to address concerns about bacterial biofilm infections. Antibiofilm strategies contain cold atmospheric plasma, nanotechnological, phage-based, antimicrobial peptides, and quorum sensing inhibition. In the last years, the studies on environmentally-friendly techniques such as essential oils and bacteriophages have been intensified to reduce microbial growth. However, the mechanisms of the biofilm matrix formation are still unclear. This review aims to discuss the latest antibiofilm therapeutic strategies against biofilm-forming bacteria.


Asunto(s)
Infecciones Bacterianas , Biopelículas , Humanos , Percepción de Quorum , Bacterias , Infecciones Bacterianas/tratamiento farmacológico , Polisacáridos
5.
ACS Cent Sci ; 8(1): 110-117, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35111901

RESUMEN

Detecting protein markers in extracellular vesicles (EVs) is becoming a useful tool for basic research and clinical diagnoses. Most EV protein assays, however, require lengthy processes-conjugating affinity ligands onto sensing substrates and affixing EVs with additional labels to maximize signal generation. Here, we present an iPEX (impedance profiling of extracellular vesicles) system, an all-electrical strategy toward fast, multiplexed EV profiling. iPEX adopts one-step electropolymerization to rapidly functionalize sensor electrodes with antibodies; it then detects EV proteins in a label-free manner through impedance spectroscopy. The approach streamlines the entire EV assay, from sensor preparation to signal measurements. We achieved (i) fast immobilization of antibodies (<3 min) per electrode; (ii) high sensitivity (500 EVs/mL) without secondary labeling; and (iii) parallel detection (quadruple) in a single chip. A potential clinical utility was demonstrated by directly analyzing plasma samples from glioblastoma multiforme patients.

6.
Adv Mater ; 34(8): e2107892, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34890082

RESUMEN

Surface chemistry critically affects the diagnostic performance of biosensors. An ideal sensor surface should be resistant to nonspecific protein adsorption, yet be conducive to analytical responses. Here a new polymeric material, zwitterionic polypyrrole (ZiPPy), is reported to produce optimal surface condition for biosensing electrodes. ZiPPy combines two unique advantages: the zwitterionic function that efficiently hydrates electrode surface, hindering nonspecific binding of hydrophobic proteins; and the pyrrole backbone, which enables rapid (<7 min), controlled deposition of ZiPPy through electropolymerization. ZiPPy-coated electrodes show lower electrochemical impedance and less nonspecific protein adsorption (low fouling), outperforming bare and polypyrrole-coated electrodes. Moreover, affinity ligands for target biomarkers can be immobilized together with ZiPPy in a single-step electropolymerization. ZiPPy-coated electrodes are developed with specificity for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The prepared sensor detects SARS-CoV-2 antibodies in human saliva down to 50 ng mL-1 , without the need for sample purification or secondary labeling.


Asunto(s)
Anticuerpos Antivirales/análisis , Técnicas Biosensibles/métodos , COVID-19/diagnóstico , Polímeros/química , Pirroles/química , Técnicas Biosensibles/instrumentación , COVID-19/virología , Técnicas Electroquímicas , Electrodos , Galvanoplastia , Oro/química , Humanos , Límite de Detección , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Saliva/metabolismo , Propiedades de Superficie
7.
Nutr Cancer ; 74(4): 1511-1518, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34459328

RESUMEN

The incidence of cancer has exhibited an increasing trend in recent years because of many reasons such as environmental and nutritional factors. There is a great need for the development of new and natural molecules with lower side effects in the therapy of cancer. It was aimed to evaluate the antiproliferative effect of semi-purified triterpene glycosides of Holothuria poli on different human cancer cell lines. The body walls of H. poli as the main sources of saponins were used and the saponin content of the extract was characterized by MALDI-TOF/MS. The antiproliferation activity of the characterized extract was tested on cancer cell lines. The extract showed antiproliferative effect on the studied cancer cell lines. The mass analysis results reveal that Holothurin A is one of the saponins within the extract. The measured IC50 values were found as 31.41 ± 2.20, 77.45 ± 0.23, and 34.79 ± 0.90 µg mL-1 for HT-29, UPCI-SCC-131, and T84 cell lines, respectively. H. poli secretes not only specific saponins but also a cocktail of them. Specific versus. cocktails of the saponins and by also applying organic modification must be studied in further research to understand their mechanisms in the antiproliferation studies since this paper reveals promising results.


Asunto(s)
Holothuria , Saponinas , Triterpenos , Animales , Línea Celular Tumoral , Holothuria/metabolismo , Humanos , Estructura Molecular , Extractos Vegetales/metabolismo , Saponinas/farmacología , Triterpenos/farmacología
8.
Artículo en Inglés | LILACS | ID: biblio-1370080

RESUMEN

Objective: it is well known that low omentin levels and reduced bioavailability of nitric oxide (NO) are outgrowth of obesity. Besides, in obese subjects, microvascular dysfunction can be an initial stage of cardiovascular diseases. This situation can be evaluated with skin laser­Doppler flowmetry (LDF). Methods: in this study we investigated the effects of 12 weeks moderate physical exercise on microvascular reactivity and plasma levels of omentin and NO in 25 overweight and obese subjects. Control group was composed of 28 sedentary participants who were neither obese nor overweight. Microvascular reactivity was handled by measurement of skin blood flow from the ring finger of the right hand with LDF, which is a non­invasive method for evaluation. With this method, it was aimed to examine the post­occlusive reactive hyperemia response of the patients. None of the participants in both groups have never followed a regular exercise schedule in their life span. Results: with regular exercise, there was a statistically significant decrease in glucose (p=0.008), cholesterol (p=0.05), and triglyceride (p=0.048) levels, while body mass index, high­density lipoprotein, and low­density lipoprotein levels did not change significantly in overweight/obese group. Also, the omentin level significantly increased (p=0.01), but NO level did not change significantly. Moreover, the amount of change in omentin and NO levels measured before and after the physical exercise were significantly correlated (r=0.57). Considering the microcirculation, rest flow (p=0.001) and peak flow value of LDF (p=0.001) increased after the physical exercise. Conclusion: our study shows that moderate physical exercise affects microvascular reactivity and plasma levels of omentin in overweight and obese subjects.


Objetivo: sabe-se que níveis baixos de omentina e a reduzida biodisponibilidade de óxido nítrico (NO) são consequências da obesidade. Além disso, a disfunção microvascular pode ser um estágio inicial de doenças cardiovasculares em indivíduos obesos. Essa situação pode ser avaliada com a fluxometria de pele laser-Doppler (LDF). Métodos: foram investigados os efeitos do exercício físico moderado por 12 semanas na reatividade microvascular e nos níveis plasmáticos de omentina e NO em 25 indivíduos com sobrepeso e obesidade. O grupo controle foi composto por 28 participantes sedentários que não eram obesos nem com sobrepeso. A reatividade microvascular foi obtida pela medida do fluxo sanguíneo da pele do dedo anelar da mão direita com LDF, que é um método não invasivo de avaliação. Com este método, objetivou-se examinar a resposta da hiperemia reativa pós-oclusiva dos pacientes. Os participantes de ambos os grupos nunca seguiram um cronograma regular de exercícios em sua vida. Resultados: com o exercício regular houve diminuição estatisticamente significativa dos níveis de glicose (p=0,008), de colesterol (p=0,05) e de triglicerídeos (p=0,048), enquanto o índice de massa corporal e os níveis de lipoproteínas de alta e baixa densidade não se alteraram significativamente no grupo com sobrepeso/obesidade. Além disso, o nível de omentina aumentou significativamente (p=0,01), mas o nível de NO não apresentou modificações significas. Observou-se, também, que as modificações nos níveis de omentina e NO mensurados antes e após o exercício físico foram significativamente correlacionados (r=0,57). Em relação à microcirculação, os valores do fluxo de repouso (p=0,001) e do valor de fluxo de pico e da LDF (p=0,001) aumentaram após o exercício físico. Conclusão: nosso estudo mostra que o exercício físico moderado afeta a reatividade microvascular e os níveis plasmáticos de omentina em indivíduos com sobrepeso e obesidade.


Asunto(s)
Humanos , Masculino , Femenino , Circulación Sanguínea , Enfermedades Cardiovasculares , Ejercicio Físico , Obesidad , Flujometría por Láser-Doppler
9.
Nat Protoc ; 16(5): 2564-2593, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33911259

RESUMEN

Organs-on-chips have emerged as viable platforms for drug screening and personalized medicine. While a wide variety of human organ-on-a-chip models have been developed, rarely have there been reports on the inclusion of sensors, which are critical in continually measuring the microenvironmental parameters and the dynamic responses of the microtissues to pharmaceutical compounds over extended periods of time. In addition, automation capacity is strongly desired for chronological monitoring. To overcome this major hurdle, in this protocol we detail the fabrication of electrochemical affinity-based biosensors and their integration with microfluidic chips to achieve in-line microelectrode functionalization, biomarker detection and sensor regeneration, allowing continual, in situ and noninvasive quantification of soluble biomarkers on organ-on-a-chip platforms. This platform is almost universal and can be applied to in-line detection of a majority of biomarkers, can be connected with existing organ-on-a-chip devices and can be multiplexed for simultaneous measurement of multiple biomarkers. Specifically, this protocol begins with fabrication of the electrochemically competent microelectrodes and the associated microfluidic devices (~3 d). The integration of electrochemical biosensors with the chips and their further combination with the rest of the platform takes ~3 h. The functionalization and regeneration of the microelectrodes are subsequently described, which require ~7 h in total. One cycle of sampling and detection of up to three biomarkers accounts for ~1 h.


Asunto(s)
Técnicas Biosensibles/instrumentación , Equipo Reutilizado , Dispositivos Laboratorio en un Chip , Biomarcadores/metabolismo , Electroquímica , Microelectrodos , Factores de Tiempo
10.
iScience ; 23(8): 101406, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32771976

RESUMEN

Rapid spread of coronavirus disease 2019 (COVID-19) is ravaging the globe. Since its first report in December 2019, COVID-19 cases have exploded to over 14 million as of July 2020, claiming more than 600,000 lives. Implementing fast and widespread diagnostic tests is paramount to contain COVID-19, given the current lack of an effective therapeutic or vaccine. This review focuses on a broad description of currently available diagnostic tests to detect either the virus (SARS-CoV-2) or virus-induced immune responses. We specifically explain the working mechanisms of these tests and compare their analytical performance. These analyses will assist in selecting most effective tests for a given application, for example, epidemiology or global pandemic research, population screening, hospital-based testing, home-based and point-of-care testing, and therapeutic trials. Finally, we lay out the shortcomings of certain tests and future needs.

11.
Pol J Microbiol ; 69(4): 411-419, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33574869

RESUMEN

Geobacillus sp. D413 and Geobacillus toebii E134 are aerobic, non-pathogenic, endospore-forming, obligately thermophilic bacilli. Gram-positive thermophilic bacilli can produce heat-resistant spores. The bacteria are indicator organisms for assessing the manufacturing process's hygiene and are capable of forming biofilms on surfaces used in industrial sectors. The present study aimed to determine the biofilm-forming properties of Geobacillus isolates and how to eliminate this formation with sanitation agents. According to the results, extracellular DNA (eDNA) was interestingly not affected by the DNase I, RNase A, and proteinase K. However, the genomic DNA (gDNA) was degraded by only DNase I. It seemed that the eDNA had resistance to DNase I when purified. It is considered that the enzymes could not reach the target eDNA. Moreover, the eDNA resistance may result from the conserved folded structure of eDNA after purification. Another assumption is that the eDNA might be protected by other extracellular polymeric substances (EPS) and/or extracellular membrane vesicles (EVs) structures. On the contrary, DNase I reduced unpurified eDNA (mature biofilms). Biofilm formation on surfaces used in industrial areas was investigated in this work: the D413 and E134 isolates adhered to all surfaces. Various sanitation agents could control biofilms of Geobacillus isolates. The best results were provided by nisin for D413 (80%) and α-amylase for E134 (98%). This paper suggests that sanitation agents could be a solution to control biofilm structures of thermophilic bacilli.


Asunto(s)
Antibacterianos/farmacología , Bacillaceae/crecimiento & desarrollo , Biopelículas/crecimiento & desarrollo , Geobacillus/crecimiento & desarrollo , Bacillaceae/efectos de los fármacos , Biopelículas/efectos de los fármacos , ADN Bacteriano/química , ADN Bacteriano/metabolismo , Desoxirribonucleasa I/metabolismo , Endopeptidasa K/metabolismo , Geobacillus/efectos de los fármacos , Nisina/farmacología , Conformación de Ácido Nucleico , Ribonucleasa Pancreática/metabolismo , alfa-Amilasas/farmacología
12.
An Acad Bras Cienc ; 91(4): e20180930, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31800697

RESUMEN

We studied dynamic thiol/disulphide homeostasis, an indicator of oxidative stress, to investigate the effects of newly initiated exercise training on sedentary obese adults. Seventeen sedentary obese adults and 15 normal-weight controls were included in the sample for this study. The obese adults were given a physical exercise training program that lasted twelve weeks. Before and after the exercise training program, blood samples were collected, and serum thiol/disulphide parameters were measured by using a novel technique. Before the start of the exercise training, it was observed that thiol/disulphide homeostasis was impaired, and this impairment was positively correlated with body mass index in sedentary obese adults because of the higher reactive oxygen species production in adipose tissue. However, while the obese participants' body mass index significantly decreased, the thiol/disulphide homeostasis parameters in the obese adults did not change over time as calculated at the baseline and compared to the calculation after the twelve weeks of exercise training. Despite a decrease in body mass index that occurred after the twelve weeks of exercise training, there was a lack of improvement in the obesity-induced impairment of thiol/disulphide homeostasis, which suggests that a newly initiated exercise training program may lead to oxidative stress.


Asunto(s)
Disulfuros/metabolismo , Ejercicio Físico , Homeostasis , Obesidad/rehabilitación , Estrés Oxidativo , Compuestos de Sulfhidrilo/metabolismo , Adulto , Índice de Masa Corporal , Peso Corporal , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/metabolismo , Conducta Sedentaria
13.
IEEE Trans Biomed Circuits Syst ; 12(5): 1056-1064, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30072339

RESUMEN

In this paper, we present the design, the implementation and the validation of a novel Internet of Things (IoT) drug monitoring system for the online continuous and simultaneous detection of two main anesthetics, e.g., propofol and paracetamol, in undiluted human serum. The described full system consists of a custom-built electronic Raspberry Pi (RPi) based Printed Circuit Board (PCB) that drives and reads out the signal from an electrochemical sensing platform integrated into a fluidic system. Thanks to the Polydimethylsiloxane (PDMS) fluidic device, the analyzed sample is automatically fluxed on the sensing site. The IoT network is supported by a Cloud system, which allows the doctor to control and share all the patient's data through a dedicated Android application and a smart watch. The validation closes with the first ever demonstration that our system successfully works for the simultaneous monitoring of propofol and paracetamol in undiluted human serum by measuring the concentration trends of these two drugs in fluxing conditions over time.


Asunto(s)
Anestésicos/sangre , Monitoreo de Drogas/métodos , Tecnología de Sensores Remotos/métodos , Nube Computacional , Dimetilpolisiloxanos/química , Monitoreo de Drogas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Grafito/química , Humanos , Internet , Tecnología de Sensores Remotos/instrumentación
14.
Sci Rep ; 8(1): 9402, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29925885

RESUMEN

Nanoscale extracellular vesicles (EVs) including exosomes (50-150 nm membrane particles) have emerged as promising cancer biomarkers due to the carried genetic information about the parental cells. However the sensitive detection of these vesicles remains a challenge. Here we present a label-free electrochemical sensor to measure the EVs secretion levels of hypoxic and normoxic MCF-7 cells. The sensor design includes two consecutive steps; i) Au electrode surface functionalization for anti-CD81 Antibody and ii) EVs capture. The label-free detection of EVs was done via Differential Pulse Voltammetry (DPV) and Electrochemical Impedance Spectroscopy (EIS). The working linear range for the sensor was 102-109 EVs/ml with an LOD 77 EVs/mL and 379 EVs/ml for EIS and DPV based detection. A blood-abundant protein, RhD was used for the selectivity test. In order to assess the performance of the biosensor, the level of EVs secretion by the human breast cancer MCF-7 cell line was compared with enzyme-linked immunosorbent assays (ELISA) and Nanoparticle Tracking Analysis (NTA). Designed label-free electrochemical sensors utilized for quantification of EVs secretion enhancement due to CoCl2-induced hypoxia and 1.23 fold increase with respect to normoxic conditions was found.


Asunto(s)
Hipoxia de la Célula/fisiología , Vesículas Extracelulares/metabolismo , Espectroscopía Dieléctrica , Ensayo de Inmunoadsorción Enzimática , Humanos , Células MCF-7
15.
Nanomaterials (Basel) ; 8(4)2018 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-29642472

RESUMEN

The unique biological features of supramolecular DNA have led to an increasing interest in biomedical applications such as biosensors. We have developed an i-motif and G-rich DNA conjugated single-walled carbon nanotube hybrid materials, which shows reversible conformational switching upon external stimuli such as pH (5 and 8) and presence of ions (Li⁺ and K⁺). We observed reversible electrochemical redox activity upon external stimuli in a quick and robust manner. Given the ease and the robustness of this method, we believe that pH- and ion-driven reversible DNA structure transformations will be utilized for future applications for developing novel biosensors.

16.
Biosensors (Basel) ; 8(1)2018 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-29315269

RESUMEN

The pharmaceutical industry is facing enormous challenges due to high drug attribution rates. For the past decades, novel methods have been developed for safety and efficacy testing, as well as for improving early development stages. In vitro screening methods for drug-receptor binding are considered to be good alternatives for decreasing costs in the identification of drug candidates. However, these methods require lengthy and troublesome labeling steps. Biosensors hold great promise due to the fact that label-free detection schemes can be designed in an easy and low-cost manner. In this paper, for the first time in the literature, we aimed to compare the potential of label-free optical and impedimetric electrochemical biosensors for the screening of antipsychotic drugs (APDs) based on their binding properties to dopamine receptors. Particularly, we have chosen a currently-used atypical antipsychotic drug (Buspirone) for investigating its dopamine D3 receptor (D3R) binding properties using an impedimetric biosensor and a nanoplasmonic biosensor. Both biosensors have been specifically functionalized and characterized for achieving a highly-sensitive and reliable analysis of drug-D3R binding. Our biosensor strategies allow for comparing different affinities against the D3R, which facilitates the identification of strong or weak dopamine antagonists via in vitro assays. This work demonstrates the unique potential of label-free biosensors for the implementation of cost-efficient and simpler analytical tools for the screening of antipsychotic drugs.


Asunto(s)
Antipsicóticos/análisis , Técnicas Biosensibles/métodos , Descubrimiento de Drogas/métodos , Evaluación Preclínica de Medicamentos/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Unión Competitiva , Buspirona/farmacología , Técnicas Electroquímicas , Humanos , Receptores de Dopamina D3/metabolismo , Agonistas de Receptores de Serotonina/farmacología
17.
Biosens Bioelectron ; 100: 139-147, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28886458

RESUMEN

Schizophrenia treatment may see a paradigm shift due to development of new atypical antipsychotic drugs (APDs), with better tolerability due to more selective dopamine (DA) receptor blockade. Monitoring of these APD candidates in biological fluids is of great importance to reduce the development cost, to clarify the mechanism of action and ultimately to support the demonstration of efficacy of these molecules. Electrochemical approaches have attracted great attention for monitoring DA and APD levels but none of the methods developed so far aimed to screen APD candidates. Herein, by this work, we propose for the first time an electrochemical ligand-binding approach for antipsychotic drug screening where competitive binding of a novel APD and DA to a dopamine D3 receptor (D3R) was investigated by looking at electrochemical signals of DA and drug before and after D3R interaction. D3R peptide was incubated with DA and/or drug first and then changes in electrochemical oxidation signals of free DA and the drug was measured by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Circular Dichroism spectroscopy was used to investigate the secondary structure of the peptide upon binding with either drug and/or DA.


Asunto(s)
Antipsicóticos/farmacología , Técnicas Biosensibles/métodos , Dopamina/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Técnicas Electroquímicas/métodos , Receptores de Dopamina D3/metabolismo , Humanos , Modelos Moleculares , Estructura Secundaria de Proteína/efectos de los fármacos , Receptores de Dopamina D3/química , Esquizofrenia/tratamiento farmacológico
18.
Biosens Bioelectron ; 99: 525-546, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28823978

RESUMEN

As being the most extensively studied, non-coding, evolutionary conserved, post-transcriptional gene regulators of genome, microRNAs (miRNAs) have taken great attention among various disciplines due to their important roles in biological processes and link with cancer. Due to their diagnostic value, there have been many conventional methods used in detection of miRNAs including northern blotting, quantitative real time PCR (qRT-PCR) and microarray technology besides novel techniques based on various nanotechnology approaches and molecular biology tools including miRNA biosensors. The aim of this review is to explain the importance of miRNAs in biomedical field with an emphasis on early cancer diagnosis by overviewing both research based and commercially available miRNA detection methods in the last decade considering their strengths and weakness with an emphasis on miRNA biosensors.


Asunto(s)
Técnicas Biosensibles/métodos , MicroARNs/aislamiento & purificación , Nanotecnología/métodos , Técnicas Biosensibles/tendencias , Regulación de la Expresión Génica/genética , Humanos , MicroARNs/genética , Nanotecnología/tendencias
19.
Adv Sci (Weinh) ; 4(5): 1600522, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28546915

RESUMEN

Development of an efficient sensing platform capable of continual monitoring of biomarkers is needed to assess the functionality of the in vitro organoids and to evaluate their biological responses toward pharmaceutical compounds or chemical species over extended periods of time. Here, a novel label-free microfluidic electrochemical (EC) biosensor with a unique built-in on-chip regeneration capability for continual measurement of cell-secreted soluble biomarkers from an organoid culture in a fully automated manner without attenuating the sensor sensitivity is reported. The microfluidic EC biosensors are integrated with a human liver-on-a-chip platform for continual monitoring of the metabolic activity of the organoids by measuring the levels of secreted biomarkers for up to 7 d, where the metabolic activity of the organoids is altered by a systemically applied drug. The variations in the biomarker levels are successfully measured by the microfluidic regenerative EC biosensors and agree well with cellular viability and enzyme-linked immunosorbent assay analyses, validating the accuracy of the unique sensing platform. It is believed that this versatile and robust microfluidic EC biosensor that is capable of automated and continual detection of soluble biomarkers will find widespread use for long-term monitoring of human organoids during drug toxicity studies or efficacy assessments of in vitro platforms.

20.
World J Microbiol Biotechnol ; 33(6): 118, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28493157

RESUMEN

The biofilm characteristics of many endospore-forming bacilli, especially the thermophiles are still unclear. In this study, a detailed identification and description of biofilm production characteristics of totally 145 isolates and reference strains belonging to Bacillaceae family, displaying thermophilic (n = 115), facultative thermophilic (n = 24) and mesophilic (n = 6) growth from genera Anoxybacillus, Geobacillus, Thermolongibacillus, Aeribacillus, Brevibacillus, Paenibacillus and Bacillus were presented. The incubation temperatures were adjusted to 37, 45 and 55-65 °C for mesophiles, facultative thermophiles, and thermophiles, respectively. The bacilli were evaluated based on their colony morphotypes on Congo red (CR) agar, their complex exopolysaccharide production on calcofluor supplemented tryptic soy agar, and as well as their pellicle formation at the liquid-air surface in tryptic soy broth cultures. Their biofilm production capabilities were also tested on abiotic surfaces of both polystyrene and stainless steel by crystal violet binding assay and viable biofilm cell enumerations, respectively. As a result, the biofilm production capacities of Bacillaceae members from genera to species level, the effects of osmolarity, temperature, incubation time and abiotic surfaces on biofilm formation as well as the CR morphotypes associated with the biofilm production were able to reveal in a wide group of bacilli. Besides, general enrichment-inoculation approaches and methodologies were also offered, which allow and facilitate the screening and determining the biofilm producing endospore forming bacilli.


Asunto(s)
Bacillaceae/clasificación , Bacillaceae/fisiología , Biopelículas/crecimiento & desarrollo , Bacillaceae/crecimiento & desarrollo , Bacillaceae/aislamiento & purificación , Medios de Cultivo/química , Calor , Concentración Osmolar , Poliestirenos , Esporas Bacterianas/crecimiento & desarrollo , Esporas Bacterianas/metabolismo , Acero Inoxidable , Temperatura , Factores de Tiempo
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