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Recent advances in detection and diagnostic tools have improved understanding and identification of plant physiological and biochemical processes. Effective and safe Surface Enhanced Raman Spectroscopy (SERS) can find objects quickly and accurately. Raman enhancement amplifies the signal by 1014-1015 to accurately quantify plant metabolites at the molecular level. This paper shows how to use functionalized perovskite substrates for SERS. These perovskite substrates have lots of surface area, intense Raman scattering, and high sensitivity and specificity. These properties eliminate sample matrix component interference. This study identified research gaps on perovskite substrates' effectiveness, precision, and efficiency in biological metabolite detection compared to conventional substrates. This article details the synthesis and use of functionalized perovskites for plant metabolites measurement. It analyzes their pros and cons in this context. The manuscript analyzes perovskite-based SERS substrates, including single-crystalline perovskites with enhanced optoelectronic properties. This manuscript aims to identify this study gap by comprehensively reviewing the literature and using it to investigate plant metabolite detection in future studies.
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Pesticides that linger in the environment and ecosystems for an extended period can cause severe and dangerous health problems in humans. To detect pesticides in foods, the development of high-sensitivity and quick screening technologies was required. This research investigated the performance of Au@Ag NPs with varying thicknesses of the silver shell for detecting trace quantities of thiabendazole (TBZ) in apples using surface-enhanced Raman spectroscopy (SERS). The Au@Ag NPs were synthesized by coating 32 nm gold seeds with different thicknesses of silver shell ranging from 2.4 to 8.7 nm, achieved by adjusting the incorporation of AgNO3 and ascorbic acid. The optimized Au@Ag NPs with a 7.3 nm silver shell demonstrated outstanding SERS activity, high sensitivity, and a detection limit of 0.05 µg/mL for TBZ. The R2 values, representing the goodness of fit, were found to be 0.990 and 0.986 for standard and real TBZ samples, respectively, indicating a strong correlation between the measured signal and the TBZ concentration. The recovery analysis showed a reliable and accurate detection capability (96 to 105%), suggesting good reliability and accuracy of the SERS-based detection using the optimal Au@Ag NPs. Overall, this research highlights the potential of SERS with optimal Au@Ag NPs for rapid and effective monitoring of pesticides in the food industry.
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Malus , Nanopartículas del Metal , Plaguicidas , Humanos , Malus/química , Tiabendazol/análisis , Plata/química , Reproducibilidad de los Resultados , Ecosistema , Nanopartículas del Metal/química , Espectrometría Raman/métodos , Plaguicidas/análisis , Oro/químicaRESUMEN
Identification of unique and specific biomarkers to better detect and quantify senescent cells remains challenging. By a global proteomic profiling of senescent human skin BJ fibroblasts induced by ionizing radiation (IR), the cellular level of pregnancy zone protein (PZP), a presumable pan-protease inhibitor never been linked to cellular senescence before, was found to be decreased by more than 10-fold, while the level of PZP in the conditioned medium was increased concomitantly. This observation was confirmed in a variety of senescent cells induced by IR or DNA-damaging drugs, indicating that high-level secretion of PZP is a novel senescence-associated secretory phenotype. RT-PCR examination verified that the transcription of the PZP gene is enhanced in various cells at senescence or upregulated following DNA damage treatment in a p53-independent manner. Moreover, pretreatment with late pregnancy serum containing a high level of PZP led to inhibition of doxorubicin-induced senescence in A549 cells, and depletion of PZP in the pregnancy serum could enhance such inhibition. Finally, the addition of immuno-precipitated PZP complexes into tissue culture attenuated the growth of A549 cells and promoted the spontaneous senescence. Therefore, we revealed that high-level secretion of PZP is a novel and unique feature associated with DNA damage-induced senescence, and secreted PZP is a positive regulator of cellular senescence, particularly during the late stage of gestation.
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Senescencia Celular , Daño del ADN , Proteínas Gestacionales , Humanos , Biomarcadores/metabolismo , Senescencia Celular/genética , Proteómica , Piel/metabolismo , Proteínas Gestacionales/metabolismo , Fibroblastos , Células A549RESUMEN
A novel deep learning-enabled smartphone platform is developed to assist a colorimetric aptamer biosensor for fast and highly sensitive detection of dimethoate. The colorimetric determination of dimethoate is based on the specific binding of dimethoate and aptamer, which leads to the aggregation of AuNPs in high-concentration NaCl solution, resulting in an obvious color change from red to blue. This color change provides sufficient data for self-learning enabled by a convolutional neural network (CNN) model, which is established to predict dimethoate concentration based on images acquired from a smartphone. To enhance user-friendliness for non-experts, the CNN model is then embedded into a smartphone app, enabling offline detection of dimethoate pesticide in real environments within just 15 min using a pre-configured colorimetric probe. The developed platform exhibits superior performance, achieving a regression coefficient of 0.9992 in the concentration range of 0-10 µM. Moreover, the app's performance is found to be consistent with the ELISA kit. These remarkable findings demonstrate the potential of combining colorimetric biosensors with smartphone-based deep learning methods for the development of portable and affordable tools for pesticide detection.
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Aptámeros de Nucleótidos , Técnicas Biosensibles , Aprendizaje Profundo , Nanopartículas del Metal , Plaguicidas , Colorimetría/métodos , Dimetoato , Teléfono Inteligente , Oro , Límite de Detección , Técnicas Biosensibles/métodosRESUMEN
Ochratoxin A (OTA) poses severe risks to the environment and human health, making the development of an accurate and sensitive analytical method for OTA detection essential. In this study, a catalytic hairpin assembly (CHA)-based Förster resonance energy transfer (FRET) aptasensor was developed to detect OTA using carbon quantum dots (CDs) and 6-carboxy-fluorescein (FAM) as dual signal readout. In the presence of OTA, the aptamer specifically interacted with OTA to release the helper DNA (HP), which could open the hairpin structure of FAM-labeled hairpin DNA 1 (H1-FAM) modified on the surface of gold nanoparticles (AuNPs). CHA between H1-FAM and hairpin H2 labeled with CDs (H2-CDs) can release HP for the next cycle, resulting in the occurrence of FRET with CDs as the energy donor and FAM as the energy acceptor. According to the ratio of FCDs/FFAM, the proposed aptasensor showed a wide linear range from 5.0 pg/mL to 3.0 ng/mL and a low detection limit of 1.5 pg/mL for OTA detection. Moreover, satisfactory results were obtained for OTA detection in rice, suggesting the potential application of this sensor in food safety analysis.
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Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Ocratoxinas , Humanos , Transferencia Resonante de Energía de Fluorescencia/métodos , Oro/química , Nanopartículas del Metal/química , Aptámeros de Nucleótidos/química , Ocratoxinas/análisis , Técnicas Biosensibles/métodos , Límite de DetecciónRESUMEN
MAIN CONCLUSION: Plant molecular biology and bacterial behaviour research in the future could focus on using genetically engineered bacteria as a sensor, hormonal/disease detector, and target gene expression, as well as establishing a bioluminescence feedback communication system. Over the last two decades, understanding plant signal transduction pathways of plant hormones has become an active research field to understand plant behavior better. To accomplish signal transduction, plants use a variety of hormones for inter- and intra-communication, and biotic or abiotic stressors activate those. Signal transduction pathways refer to the use of various communication methods by effectors to elicit a response at the molecular level. Research methodologies such as inter-kingdom signaling have been introduced to study signal transduction and communication pathways, or what we can term plant molecular communication. However, stochastic qualities are inherent in most technologies used to monitor these biological processes. Molecular communication (MC) is a new research topic that uses the natural features of biological organisms to communicate and aims to manipulate their stochastic nature to achieve the desired results. MC is a multidisciplinary research field inspired by the use of molecules to store, spread, and receive information between biological organisms known as "Biological Nanomachines." It has been used to demonstrate how biological entities may be characterised, modelled, and engineered as communication devices in the same manner as traditional communication technologies are. We attempted to link MC and PLANT'S MC in this study and we believe that reasonable combined efforts may be made to use the functional applications of MC for detecting and understanding molecular-level activities such as signaling transduction pathways in crops.
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Productos Agrícolas , Reguladores del Crecimiento de las Plantas , Bacterias/metabolismo , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Transducción de Señal/fisiologíaRESUMEN
Abscisic acid (ABA), as the most common plant hormone in the growth of wheat, can greatly affect the yield when its levels deviate from normal. Therefore, highly sensitive and selective detection of this hormone is greatly needed. In this work, we developed an aptamer sensor based on surface-enhanced Raman spectroscopy (SERS) and applied it for the high sensitivity detection of ABA. Biotin-modified ABA aptamer complement chains were modified on ferrosoferric oxide magnetic nanoparticles (Fe3O4MNPs) and acted as capture probes, and sulfhydryl aptamer (SH-Apt)-modified silver-coated gold nanospheres (Au@Ag NPs) were used as signal probes. Through the recognition of the ABA aptamer and its complementary chains, an aptamer sensor based on SERS was constructed. As SERS internal standard molecules of 4-mercaptobenzoic acid (4-MBA) were encapsulated between the gold core and silver shell of the signal probes; the constructed aptamer sensor generated a strong SERS signal of 4-MBA after magnetic separation. When there were ABA molecules in the detection system, with the preferential binding of ABA aptamer and ABA molecule, the signal probes were released from the capture probes, after magnetic separation, leading to a linear decrease in SERS intensity of 4-MBA. Thus, the detection response was linear over a logarithmic concentration range, with an ultra-low detection limit of 0.67 fM. In addition, the practical use of this assay method was demonstrated in ABA detection from fresh wheat leaves, with a relative error (RE) of 5.43-8.94% when compared with results from enzyme-linked immunosorbent assay (ELISA). The low RE value proves that the aptamer sensor will be a promising method for ABA detection.
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Aptámeros de Nucleótidos , Nanopartículas del Metal , Ácido Abscísico , Aptámeros de Nucleótidos/química , Oro/química , Límite de Detección , Nanopartículas del Metal/química , Reguladores del Crecimiento de las Plantas , Espectrometría Raman/métodosRESUMEN
The present study aimed to perform chromosome examination and pedigree analysis on three patients with semen abnormality who had undergone in vitro fertilization-embryo transfer (IVF-ET). Peripheral blood cell culture and chromosome karyotyping were performed on 4,200 individuals who had undergone chromosome examination. Among them, 155 pregnant women who had successfully conceived were subjected to amniotic cell culture and chromosome karyotyping and those with abnormal chromosome karyotype were further subjected to C-banding and whole-genome sequencing. Mosaicism for a 46,X,inv(Y)(p11.2q11.2)pat/45,X karyotype was identified in the probands and immediate adult male relatives. The incidence of this mosaicism in the study population was only 0.07% (3/4,200), which is reported for the first time. For the proband of pedigree A, the results of whole-genome sequencing and other tests were normal, and the chromosome karyotype of IVF fetuses was 46,X,inv(Y)(p11.2q11.2)pat. All the male members of three pedigrees have normal phenotypes, with no features of Turner's syndrome (45,X) or hermaphroditism (45,X/46,XY), suggesting that the inverted Y chromosome is extremely unstable and particularly susceptible to loss in somatic cells. So we speculate this karyotype may be a unique type of inverted Y chromosome in somatic cells.
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Cromosomas Humanos X/genética , Cromosomas Humanos Y/genética , Mosaicismo , Adulto , Pueblo Asiatico/genética , China , Femenino , Humanos , Cariotipificación , Masculino , Linaje , EmbarazoRESUMEN
BACKGROUND: Hereditary cancer syndromes have inherited germline mutations which predispose to benign and malignant tumors. Understanding of the molecular causes in hereditary cancer syndromes has advanced cancer treatment and prevention. However, the causal genes of many hereditary cancer syndromes remain unknown due to their rare frequency of mutation. METHODS: A large Chinese family with a history of hereditary liver-colon cancer syndrome was studied. The genomic DNA was extracted from the blood samples of involved family members, whole-exome sequencing was performed to identify genetic variants. Functional validation of a candidate variant was carried out using gene expression, gene knockout and immunohistochemistry. RESULTS: The whole-exome of the proband diagnosed with colon cancer was sequenced in comparison with his mother. A total of 13 SNVs and 16 InDels were identified. Among these variants, we focused on a mutation of Rab43 gene, a GTPase family member involving in protein trafficking, for further validation. Sanger DNA sequencing confirmed a mutation (c: 128810106C > T, p: A158T) occurred in one allele of Rab43 gene from the proband, that heterozygous mutation also was verified in the genome of the proband's deceased father with liver cancer, but not in his healthy mother and sister. Ectopic expression of the Rab43 A158T mutant in Huh7 cells led to more enhanced cell growth, proliferation and migration compared to the expression of wild type Rab43. Conversely, knockout of Rab43 in HepG2 cells resulted in slow cell growth and multiple nuclei formation and impaired activation of Akt. Finally, a positive correlation between the expression levels of Rab43 protein and cancer development in that family was confirmed. CONCLUSIONS: A germline mutation of Rab43 gene is identified to be associated with the onset of a familial liver-colon cancer syndrome. Our finding points to a potential role of protein trafficking in the tumorigenesis of the familial cancer syndrome, and helps the genetic counseling to the affected family members.
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Neoplasias del Colon/genética , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Neoplasias Hepáticas/genética , Síndromes Neoplásicos Hereditarios/genética , Proteínas de Unión al GTP rab/genética , Alelos , Carcinogénesis/genética , Neoplasias del Colon/sangre , Femenino , Técnicas de Inactivación de Genes , Células HeLa , Células Hep G2 , Humanos , Neoplasias Hepáticas/sangre , Masculino , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/sangre , Linaje , Proteínas Proto-Oncogénicas c-akt/metabolismo , Análisis de Secuencia de ADN , Secuenciación del ExomaRESUMEN
In this study, a simple colorimetric probe was developed for rapid and highly sensitive detection of malathion based on gold nanoparticles (AuNPs) anti-aggregation mechanism. A certain amount of NaOH can cause the aggregation of citrate-stabilized AuNPs due to the electrostatic interactions, and the color of AuNP solution changes from wine-red to gray. While in the presence of malathion, malathion is easily hydrolyzed in a strong alkali environment (pH > 9), followed by the production of a mass of negative charges, and thus the aggregated AuNPs turns to well-dispersed and the color of AuNP solution changes from gray to wine-red. This characteristic change can be visualized with the naked eye and quantitatively detected by an ultraviolet-visible (UV-Vis) spectrometer. Under optimized conditions, this probe exhibited a linear response to malathion in the concentration range of 0.05-0.8 µM with a limit of detection (LOD) down to 11.8 nM. The probe also showed good specificity for malathion detection in the presence of other interfering pesticide residues. Furthermore, the probe was successfully employed to detect malathion in environmental samples, with a recovery of 94-107% and a relative standard deviation (RSD) less than 8%. The results demonstrated that the proposed colorimetric probe based on anti-aggregation of AuNPs could be used for quantitative analysis of malathion and provided great potential for malathion determination in environmental samples.
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A multi-channel localized surface plasmon resonance system is described for absorptiometric determination of abscisic acid (ABA). The system is making use of gold nanoparticles and consists of a broadband light source, a multi-channel alignment device, and a fiber spectrometer. The method is based on the specific interaction between an ABA-binding aptamer and ABA. This induces the growth of gold nanoparticles (AuNPs) functionalized with a polyadenine-tailed aptamer that act as optical probes. Different concentrations of ABA give rise to varied morphologies of grown AuNPs. This causes a change of absorption spectra which is recorded by the system. ABA can be quantified by measurement of the peak wavelength shifts of grown AuNPs. Under optimized conditions, this method shows a linear relationship in the 1 nM to 10 µM ABA concentration range. The detection limit is 0.51 nM. The sensitivity of the ABA assay is strongly improved compared to the method based on salt-induced AuNP aggregation. This is attributed to the use of a poly-A-tailed aptamer and the catalytic ability of AuNPs. In the actual application, the ABA concentration of ABA in fresh leaves of rice is measured with the maximum relative error of 8.03% in comparison with the ELISA method. Graphical abstractSchematic representation of an absorptiometric approach for determination of abscisic acid based on the growth of polyA-tailed aptamer-AuNPs probes and a multi-channel localized surface plasmon resonance system.
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Ácido Abscísico/análisis , Aptámeros de Nucleótidos/química , Oro/química , Nanopartículas del Metal/química , Poli A/química , Resonancia por Plasmón de Superficie/métodos , Ácido Abscísico/química , Ácido Abscísico/metabolismo , Absorción Fisicoquímica , Aptámeros de Nucleótidos/metabolismo , Secuencia de Bases , Oryza/químicaRESUMEN
Edible gelatin has been widely used as a food additive in the food industry, and illegal adulteration with industrial gelatin will cause serious harm to human health. The present work used laser-induced breakdown spectroscopy (LIBS) coupled with the partial least square-support vector machine (PLS-SVM) method for the fast and accurate estimation of edible gelatin adulteration. Gelatin samples with 11 different adulteration ratios were prepared by mixing pure edible gelatin with industrial gelatin, and the LIBS spectra were recorded to analyze their elemental composition differences. The PLS, SVM, and PLS-SVM models were separately built for the prediction of gelatin adulteration ratios, and the hybrid PLS-SVM model yielded a better performance than only the PLS and SVM models. Besides, four different variable selection methods, including competitive adaptive reweighted sampling (CARS), Monte Carlo uninformative variable elimination (MC-UVE), random frog (RF), and principal component analysis (PCA), were adopted to combine with the SVM model for comparative study; the results further demonstrated that the PLS-SVM model was superior to the other SVM models. This study reveals that the hybrid PLS-SVM model, with the advantages of low computational time and high prediction accuracy, can be employed as a preferred method for the accurate estimation of edible gelatin adulteration.
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This publisher's note corrects the author listing and a figure caption in Appl. Opt.57, 3481 (2018)APOPAI0003-693510.1364/AO.57.003481.
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Chinese hybrid rice of different varieties, growing in paddies in the Pingqiao district, north of Xinyang city, Henan province, China, was studied in detailed spectroscopic characteristics using laser-induced fluorescence. The base for the studies was the new South China Normal University mobile lidar laboratory, which was dispatched on site, providing facilities both for laboratory studies using a 405 nm excitation source as well as remote sensing measurements at ranges from around 40 m-120 m, mostly employing the 532 nm output from a Nd:YAG laser. We, in particular, studied the spectral influence of the species varieties as well as the level of nitrogen fertilization supplied. Specially developed contrast functions as well as multivariate techniques with principal components and Fisher's discriminate analyses were applied, and useful characterization of the rice could be achieved. The chlorophyll content mapping of the 30 zones was obtained with the remote sensing measurements.
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Clorofila/análisis , Fluorescencia , Láseres de Estado Sólido , Nitrógeno/análisis , Oryza/química , Tecnología de Sensores Remotos/métodos , Espectrometría de Fluorescencia , China , Oryza/genéticaRESUMEN
Corn stalk lodging is caused by different factors, including severe wind storms, stalk cannibalization, and stalk rots, and it leads to yield loss. Determining how to rapidly evaluate corn lodging resistance will assist scientists in the field of crop breeding to understand the contributing factors in managing the moisture, chemical fertilizer, and weather conditions for corn growing. This study proposes a non-destructive and direction-insensitive method, using a strain sensor and two single axis angle sensors to measure the corn stalk lodging resistance in the field. An equivalent force whose direction is perpendicular to the stalk is utilized to evaluate the corn lodging properties when a pull force is applied on the corn stalk. A novel measurement device is designed to obtain the equivalent force with the coefficient of variation (CV) of 4.85%. Five corn varieties with two different planting densities are arranged to conduct the experiment using the novel measurement device. The experimental results show that the maximum equivalent force could reach up to 44 N. A strong relationship with the square of the correlation coefficient of 0.88 was obtained between the maximum equivalent forces and the corn field’s stalk lodging rates. Moreover, the stalk lodging angles corresponding to the different pull forces over a measurement time of 20 s shift monotonically along the equivalent forces. Thus, the non-destructive and direction-insensitive method is an excellent tool for rapid analysis of stalk lodging resistance in corn, providing critical information on in-situ lodging dynamics.
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Laser-induced fluorescence is an important technique to study photosynthesis and plants. Information on chlorophyll and other pigments can be obtained. We have been using a mobile laboratory in a Chinese experimental farm setting to study maize (Zea mays L.) leaves by reflectance and fluorescence measurements and correlated the spectroscopic signals to the amount of fertilizer supplied. Further, we studied five different species of maize using the remote monitoring of the fluorescence signatures obtained with the same mobile laboratory, but now in a laser radar remote-sensing configuration. The system separation from the target area was 50 m, and 355 nm pulsed excitation using the frequency-tripled output from an Nd:YAG laser was employed. Principal component analysis and linear discriminant analysis were combined to identify the different maize species using their fluorescence spectra. Likewise, the spectral signatures in reflectance and fluorescence frequently allowed us to separate different fertilizer levels applied to plants of the same species.
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The purpose of this study was to develop a portable surface plasmon resonance (SPR) bioanalyzer for the sensitive detection of Escherichia coli O157:H7 in comparison with an enzyme-linked immunosorbent assay (ELISA). The experimental setup mainly consisted of an integrated biosensor and a homemade microfluidic cell with a three-way solenoid valve. In order to detect Escherichia coli O157:H7 using the SPR immunoassay, 3-mercaptopropionic acid (3-MPA) was chemisorbed onto a gold surface via covalent bond for the immobilization of biological species. 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) were used as crosslinker reagents to enable the reaction between 3-MPA and Escherichia coli O157:H7 antibodies by covalent -CO-NH- amide bonding. The experimental results were obtained from the Escherichia coli O157:H7 positive samples prepared by 10-, 20-, 40-, 80-, and 160-fold dilution respectively, which show that a good linear relationship with the correlation coefficient R of 0.982 existed between the response units from the portable SPR bioanalyzer and the concentration of Escherichia coli O157:H7 positive samples. Moreover, the theoretical detection limit of 1.87 × 10³ cfu/mL was calculated from the positive control samples. Compared with the Escherichia coli O157:H7 ELISA kit, the sensitivity of this portable SPR bioanalyzer is four orders of magnitude higher than the ELISA kit. The results demonstrate that the portable SPR bioanalyzer could provide an alternative method for the quantitative and sensitive determination of Escherichia coli O157:H7 in field.
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Técnicas Biosensibles/métodos , Resonancia por Plasmón de Superficie/métodos , Ensayo de Inmunoadsorción Enzimática , Escherichia coli O157/fisiología , Inmunoensayo/métodos , SuccinimidasRESUMEN
Ethylene as an indicator for evaluating fruit ripening can be measured by very sensitive electrochemical gas sensors based on a high-resolution current produced by a bias potential applied to the electrodes. For this purpose, a measurement system for monitoring ethylene gas concentrations to evaluate fruit ripening by using the electrochemical ethylene sensor was successfully developed. Before the electrochemical ethylene sensor was used to measure the ethylene gas concentrations released from fruits, a calibration curve was established by the standard ethylene gases at concentrations of 2.99 ppm, 4.99 ppm, 8.01 ppm and 10 ppm, respectively, with a flow rate of 0.4 L·min(-1). From the calibration curve, the linear relationship between the responses and concentrations of ethylene gas was obtained in the range of 0-10 ppm with the correlation coefficient R² of 0.9976. The micropump and a novel signal conditioning circuit were implemented in this measurement, resulting in a rapid response in detecting ethylene concentrations down to 0.1 ppm in air and in under 50 s. In this experiment, three kinds of fruits-apples, pears and kiwifruits-were studied at a low concentration (under 0.8 ppm) of trace ethylene content in the air exhaled by fruits. The experimental results showed that a low cost, compact measurement system constructed by using an electrochemical ethylene sensor has a high sensitivity of 0.3907 V·ppm(-1) with a theoretical detection limit of 0.413 ppm, and is non-invasive and highly portable.
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Técnicas Biosensibles/instrumentación , Etilenos/aislamiento & purificación , Frutas/crecimiento & desarrollo , Gases/aislamiento & purificación , Técnicas Electroquímicas , Etilenos/metabolismo , Frutas/química , Frutas/metabolismo , Gases/metabolismo , Límite de DetecciónRESUMEN
The aim of this study was to develop a circuit for an inexpensive portable biosensing system based on surface plasmon resonance spectroscopy. This portable biosensing system designed for field use is characterized by a special structure which consists of a microfluidic cell incorporating a right angle prism functionalized with a biomolecular identification membrane, a laser line generator and a data acquisition circuit board. The data structure, data memory capacity and a line charge-coupled device (CCD) array with a driving circuit for collecting the photoelectric signals are intensively focused on and the high performance analog-to-digital (A/D) converter is comprehensively evaluated. The interface circuit and the photoelectric signal amplifier circuit are first studied to obtain the weak signals from the line CCD array in this experiment. Quantitative measurements for validating the sensitivity of the biosensing system were implemented using ethanol solutions of various concentrations indicated by volume fractions of 5%, 8%, 15%, 20%, 25%, and 30%, respectively, without a biomembrane immobilized on the surface of the SPR sensor. The experiments demonstrated that it is possible to detect a change in the refractive index of an ethanol solution with a sensitivity of 4.99838 × 10(5) ΔRU/RI in terms of the changes in delta response unit with refractive index using this SPR biosensing system, whereby the theoretical limit of detection of 3.3537 × 10(-5) refractive index unit (RIU) and a high linearity at the correlation coefficient of 0.98065. The results obtained from a series of tests confirmed the practicality of this cost-effective portable SPR biosensing system.
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Electrónica , Resonancia por Plasmón de Superficie/instrumentación , Conversión Analogo-Digital , Calibración , Diseño de Equipo , Etanol/análisis , Procesamiento de Señales Asistido por Computador , Soluciones , Factores de TiempoRESUMEN
The purpose of this study was to analyze the temporal gene expression in salivary and lacrimal glands of Sjögren's syndrome (SS) based on time-series microarray data. We downloaded gene expression data GSE15640 and GSE48139 from gene expression omnibus and identified differentially expressed genes (DEGs) at varying time points using a modified Bayes analysis. Gene clustering was applied to analyze the expression differences in time series of the DEGs. Protein-protein interaction networks were used for searching the hub genes, and gene ontology (GO) and KEGG pathways were applied to analyze the DEGs at a functional level. A total of 744 and 1,490 DEGs were screened out from the salivary glands and lacrimal glands, respectively. Among these genes, 194 were overlapped between salivary glands and lacrimal glands, and these genes were compartmentalized into six clusters with different expression profiles. The GO terms of intracellular transport, protein transport and protein localization were significantly enriched by DEGs in salivary glands; while in the lacrimal glands, DEGs were significantly enriched in protein localization, establishment of protein localization and protein transport. Our results suggest that the SS pathogenesis was significantly different in time series in the salivary and lacrimal glands. The DEGs whose expressions may correlate with molecular mechanisms of SS in our study might provide new insight into the underlying cause or regulation of this disease.