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1.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35012978

RESUMO

Preventing pathogenic viral and bacterial transmission in the human environment is critical, especially in potential outbreaks that may be caused by the release of ancient bacteria currently trapped in the permafrost. Existing commercial disinfectants present issues such as a high carbon footprint. This study proposes a sustainable alternative, a bioliquid derived from biomass prepared by hydrothermal liquefaction. Results indicate a high inactivation rate of pathogenic virus and bacteria by the as-prepared bioliquid, such as up to 99.99% for H1N1, H5N1, H7N9 influenza A virus, and Bacillus subtilis var. niger spores and 99.49% for Bacillus anthracis Inactivation of Escherichia coli and Staphylococcus epidermidis confirmed that low-molecular-weight and low-polarity compounds in bioliquid are potential antibacterial components. High temperatures promoted the production of antibacterial substances via depolymerization and dehydration reactions. Moreover, bioliquid was innoxious as confirmed by the rabbit skin test, and the cost per kilogram of the bioliquid was $0.04427, which is notably lower than that of commercial disinfectants. This study demonstrates the potential of biomass to support our biosafety with greater environmental sustainability.


Assuntos
Biomassa , Contenção de Riscos Biológicos , Meio Ambiente , Energia Renovável , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Humanos , Testes de Sensibilidade Microbiana , Peso Molecular , Pandemias , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/ultraestrutura
2.
Anal Chem ; 94(44): 15472-15480, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36282886

RESUMO

Integrated clustered regularly interspaced short palindromic repeat (CRISPR)-loop-mediated amplification (LAMP) technology is of great importance in CRISPR-based diagnostic systems, which urgently needs to be developed to improve diagnostic accuracy. A labor-free, contamination-free, and fully automated droplet manipulation platform for the CRISPR-LAMP technology has not been developed before. Herein, we propose a fully automated CRISPR-LAMP platform, which can precisely manipulate the CRISPR-LAMP droplet and perform combined reactions with high sensitivity and specificity. SARS-CoV-2 Spike T478K, D614G, P681R, and P681H mutations, typical point mutations of B.1.617.2 (Delta) and Omicron variants, are monitored with this platform with a detection limit of 102 copies/µL. Allele discrimination between the mutants and wild type is significant with the designed one/two-mismatch CRISPR RNA (crRNA) at a limit of 102 copies/µL. Chemically synthesized and modified crRNAs greatly increase the CRISPR-LAMP signal, which advance the wide application. Combined with the previously developed RdRp CRISPR-LAMP assay, clinical results showed that Spike T478K and P681H can discriminate the mutant type form the wild type with 70% (49.66-85.50%, 95% confidence interval) and 78% (57.27-90.62%, 95% confidence interval) sensitivity, respectively, and 100% specificity (51.68-100%, 95% confidence interval), and the RdRp target can detect SARS-CoV-2 strains with 85% sensitivity (65.39-95.14%, 95% confidence interval) and 100% specificity (51.68-100%, 95% confidence interval). We believe that this automatic digital microfluid (DMF) system can advance the integrated CRISPR-LAMP technology with higher stability, sensitivity, and practicability, also for other CRISPR-associated diagnostic platforms.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Polimerase Dependente de RNA , Sensibilidade e Especificidade
3.
Anal Chem ; 93(28): 9835-9844, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34232631

RESUMO

Insulin resistance (IR) is a typical sign of metabolic dysregulation caused by fine particulate matter (PM2.5), but the underlying signaling has not been clearly determined. Herein, a microfluidic liver-kidney microphysiological system (LK-MPS) is presented to assess the signaling pathways of IR generated by PM2.5 at 200 µg/mL for 24 h. The LK-MPS device consisted of a biomimetic liver-kidney architecture and reconstructed two circulation paths: the liver metabolism-kidney excretion (LM-KE) and kidney excretion-liver metabolism (KE-LM), by which PM2.5 is feasibly distributed in the two organs. Transmission electron microscopy (TEM) analysis revealed that PM2.5 can embed in the cytoplasm and nuclei, undergo transport by vesicles, and lead to the destruction of mitochondria. Further comprehensive immunofluorescence, enzyme-linked immunosorbent assays (ELISAs) and untargeted metabolomic analyses confirmed that PM2.5 disturbed the classic IRS-1/AKT signaling pathway (INSR, IRS-1, PI3K, AKT, GLUT2, GLUT4, and FOXO1 downregulated) and IR-related metabolic pathways: UDP-hexosamine (UDP-GlcNAc), gluconeogenesis (ß-d-glucose 6-phosphate), and lipid biosynthesis (ceramide (Cer) and triacylglycerol (TG)) pathways, leading to the disorder of glucose levels. Collectively, these disorders aggravate hepatic and renal IR. Pearson's correlation coefficient test showed that elemental carbon (EC), polycyclic aromatic hydrocarbons (PAHs), and metals (Ca, Co, and V) were negatively correlated to the dysregulated proteins (INSR, IRS-1, AKT, FOXO1, GLUT2, and GLUT4). These findings may partially explain IR-related signaling pathways triggered by PM2.5.


Assuntos
Resistência à Insulina , Insulina , Humanos , Rim/metabolismo , Fígado/metabolismo , Microfluídica , Material Particulado/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
4.
Anal Chem ; 93(48): 16184-16193, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34818890

RESUMO

Nowadays, rapid and accurate diagnosis of respiratory tract viruses is an urgent need to prevent another epidemic outbreak. To overcome this problem, we have developed a clustered, regularly interspaced short palindromic repeats (CRISPR) loop mediated amplification (LAMP) technology to detect influenza A virus, influenza B virus, respiratory syncytial A virus, respiratory syncytial B virus, and severe acute respiratory syndrome coronavirus 2, including variants of concern (B.1.1.7), which utilized CRISPR-associated protein 12a (Cas12a) to advance LAMP technology with the sensitivity increased 10 times. To reduce aerosol contamination in CRISPR-LAMP technology, an uracil-DNA-glycosylase-reverse transcription-LAMP system was also developed which can effectively remove dUTP-incorporated LAMP amplicons. In vitro Cas12a cleavage reaction with 28 crRNAs showed that there were no position constraints for Cas12a/CRISPR RNA (crRNA) recognition and cleavage in LAMP amplicons, and even the looped position of LAMP amplicons could be effectively recognized and cleaved. Wild-type or spike N501Y can be detected with a limit of detection of 10 copies/µL (wild-type) even at a 1% ratio level on the background (spike N501Y). Combining UDG-RT-LAMP technology, CRISPR-LAMP design, and mutation detection design, we developed a CRISPR-LAMP detection platform that can precisely diagnose pathogens with better stability and significantly improved point mutation detection efficiency.


Assuntos
COVID-19 , SARS-CoV-2 , Sistemas CRISPR-Cas/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico
5.
Part Fibre Toxicol ; 18(1): 31, 2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-34419099

RESUMO

BACKGROUND: Exposure to indoor air pollution from solid fuel combustion is associated with lung diseases and cancer. This study investigated the cytotoxicity and molecular mechanisms of biomass combustion-derived particles in human pulmonary alveolar epithelial cells (HPAEpiC) using a platform that combines air-liquid interface (ALI) and dynamic culture (DC) systems. METHODS: HPAEpiC were cultured on the surface of polycarbonate (PC) membranes on the ALI-DC platform. The cells were sprayed with an aerosolized solution of biomass combustion soluble constituents (BCSCs) and simultaneously nourished with culture medium flowing beneath the permeable PC membranes. The ALI-DC method was compared with the traditional submerged culture approach. BCSC particle morphology and dosages deposited on the chip were determined for particle characterization. Flow cytometry, scanning electron microscopy, and transmission electron microscopy were used to investigate the apoptosis rate of HPAEpiC and changes in the cell ultrastructure induced by BCSCs. Additionally, the underlying apoptotic pathway was examined by determining the protein expression levels by western blotting. RESULTS: Scanning electron microscope images demonstrated that the sample processing and delivering approach of the ALI-DC platform were suitable for pollutant exposure. Compared with the submerged culture method, a significant decline in cell viability and increase in apoptosis rate was observed after BCSC exposure on the ALI-DC platform, indicating that the ALI-DC platform is a more sensitive system for investigating cytotoxicity of indoor air pollutants in lung cells. The morphology and ultrastructure of the cells were damaged after exposure to BCSCs, and the p53 pathway was activated. The Bcl-2/Bax ratio was reduced, upregulating caspase-9 and caspase-3 expression and subsequently inducing apoptosis of HPAEpiC. The addition of N-acetyl cysteine antioxidant significantly alleviated the cytotoxicity induced by BCSCs. CONCLUSION: A novel ALI-DC platform was developed to study the cytotoxicity of air pollutants on lung cells. Using the platform, we demonstrated that BCSCs could damage the mitochondria, produce reactive oxygen species, and activate p53 in HPAEpiC, ultimately inducing apoptosis.


Assuntos
Poluentes Atmosféricos , Células Epiteliais Alveolares , Biomassa , Sobrevivência Celular , Células Epiteliais , Humanos , Pulmão
6.
Ecotoxicol Environ Saf ; 223: 112591, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34364123

RESUMO

As a new type of environmental pollutant, microplastics (MPs) can adsorb residual organochlorine pesticides (OCPs) in the soil and pose a severe threat to the soil ecosystems. To understand the interaction between soil MPs and OCPs, the sorption of two kinds of OCPs, including hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs), on polyethylene (PE) microplastics in soil suspension was studied through sorption kinetics and isotherm models. The effects of solution/soil ratio and MPs diameter on sorption were examined. The kinetic experiment results show that the sorption equilibrium was 12 h, and the sorption process of OCPs on MPs can be well described by a pseudo-second-order model. The Freundlich model (R2 = 0.942-0.997) provides a better fit to the sorption isotherm data than the Langmuir model (R2 = 0.062-0.634), indicating that the sorption process takes place on the nonuniform surface of MPs. The MPs had a good sorption effect on OCPs when the solution/soil ratio was from 75:1 to 100:1. As the diameter of MPs increases, the sorption capacity decreases. These results provide support for further research on microplastic pollution in soil.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes do Solo , Adsorção , Ecossistema , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Microplásticos , Plásticos , Polietileno , Solo
7.
Analyst ; 145(1): 277-285, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31746822

RESUMO

Detecting atmospheric bioaerosols in a quantitative way is highly desirable for public health and safety. This work demonstrates that surface-enhanced Raman spectroscopy (SERS) is a simple and rapid analytical technique for the detection of atmospheric bioaerosols, on a Klarite substrate. For both simulated and ambient bioaerosols, this detection assay results in an increase in the enhancement factor of the Raman signal. We report a strong SERS signal generated by bioaerosols containing living Escherichia coli deposited on Klarite. Furthermore, we demonstrate that SERS mapping can be used to estimate the percentage of airborne, living Escherichia coli. Moreover, Klarite provides differently distinct SERS spectra at different bacterial growth phases, indicating its potential to identify changes occurring in the bacterial envelope. Finally, we applied SERS for the rapid detection of Escherichia coli in ambient bioaerosols without using time-consuming and laborious culture processes. Our results represent rapid, culture-free and label-free detection of airborne bacteria in the real-world environment.


Assuntos
Aerossóis/análise , Técnicas Bacteriológicas/métodos , Escherichia coli/isolamento & purificação , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Escherichia coli/classificação , Ouro/química , Viabilidade Microbiana , Silício/química
8.
Ecotoxicol Environ Saf ; 170: 796-803, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30605872

RESUMO

The ability to analyze biotoxicity of atmospheric pollution plays an important role in public health. It provides the potential to directly analyze the health information of at-risk individuals. Although air quality standards have received significant attention in many countries, the potential for better biotoxicity assessment has remained largely unexplored. Here we propose a method using one kind of luminescent bacterium Photobacterium phosphereum to detect the biotoxicity of atmospheric particulate matter ≤ 2.5 µm (PM2.5). Combined with the results of air pollution data of the year 2013-2014, this method has been proven to have good biotoxicity detection performance, and can evaluate the severity of at least 85% of PM2.5 related biotoxicity in Shanghai during this time period. Based on an established algorithm of this detection system, the biotoxicity of twelve PM2.5 real samples (collected over a month) were tested and divided into different biotoxicity levels. It allows an effective evaluation of biotoxicity of PM2.5 due to the quick and sensitive response of bioluminescence to the concentration of toxic components, which provides a valuable reference to evaluate the biotoxicity of PM2.5. This established method can be easily applied to the analysis and evaluation of any other PM2.5 samples assay by following the steps.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Photobacterium , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Bioensaio , Monitoramento Ambiental/métodos , Medições Luminescentes , Tamanho da Partícula , Material Particulado/análise
9.
Anal Chem ; 89(10): 5413-5421, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28447797

RESUMO

PM2.5 (particulate matter less than 2.5 µm in diameter) is considered as a harmful carcinogen. Determining the precise relationship between the chemical constituents of PM2.5 in the air and cancer progression could aid the treatment of environment related disease and establishing risk reduction strategies. Herein, we used transcriptomics (RNA-seq) and an integrated microfluidic system to identify the global gene expression and differential target proteins expression induced by ambient fine particles collected from the heavy haze in China. The results clearly indicated that cancer related pathways exhibited the strongest dysregulation. The ambient fine particles could be uptaken into the cells by pinocytosis, mainly promoting the PI3K-Akt pathway, FGF/FGFR/MAPK/VEGF signaling, and the JAK-STAT pathway, leading to evading apoptosis, sustained angiogenesis, and cell proliferation, which are the most important hallmarks of cancer. And fine particles also have been demonstrated to create intracellular reactive oxygen species (ROS) and mitochondrial ROS, change intracellular free Ca2+, and induce apoptosis, which are all key players in mediating cancer progression. It was observed by transmission electron microscopy (TEM) that the particles from the haze could enter the mitochondria, resulting in disturbance of the mitochondrial membrane and disruption of the mitochondria, and these particles can even enter inside the nucleus. It was also found in our study of organics (OC, PAHs) and metals (Zn, As, V) that compounds of fine particles were more closely associated with the exacerbation of cancer and secondary aerosols generated by traffic had the largest impact on cancer related signal transductions.


Assuntos
Apoptose/efeitos dos fármacos , Carcinógenos/toxicidade , Microfluídica/métodos , Material Particulado/toxicidade , Transdução de Sinais/efeitos dos fármacos , Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Brônquios/citologia , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Cálcio/metabolismo , Carcinógenos/química , Linhagem Celular , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Material Particulado/química , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma/efeitos dos fármacos
10.
Analyst ; 141(5): 1637-40, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26854120

RESUMO

We report a portable "sample to answer" system for the rapid detection of airborne pathogens for the first time. The system contains a key microfluidic chip which fulfills both pathogen enrichment and biological identification functions. The system realizes simple operation and less human intervention as well as minimum reagent contamination. The operation is user-friendly and suitable for field and point-of-care applications. The system is capable of handling detection of different pathogens by changing the primers.


Assuntos
Microbiologia do Ar , Dispositivos Lab-On-A-Chip , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Fatores de Tempo
11.
Anal Chem ; 86(12): 5815-21, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24857567

RESUMO

Airborne Mycobacterium tuberculosis is the main source of tuberculosis infection, which is known as one of the worldwide infectious diseases. Direct capture and analysis of airborne Mycobacterium tuberculosis is essential for disease prevention and control. At present, low concentration of pathogens directly collected from the air is the major drawback for rapid analysis. Herein an integrated microfluidic system capable of airborne Mycobacterium tuberculosis capture, enrichment, and rapid bacteriological immunoassay was developed. The whole detection time was decreased to less than 50 min including 20 min of enrichment and 30 min of immunoreaction analysis. It had the advantages of low detection limit, fast detection speed, and low reagent consumption compared with conventional techniques, showing the potential to become a new airborne pathogen analysis platform.


Assuntos
Microbiologia do Ar , Microfluídica/instrumentação , Mycobacterium tuberculosis/isolamento & purificação , Imunoensaio
12.
Bull Environ Contam Toxicol ; 92(1): 119-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24318164

RESUMO

Mass growth of blue-green algae in eutrophic water bodies leads to a large amount of toxins, e.g. microcystins (MCs). How to remove MCs from water bodies is an environmental problem. In this study, an algicidal bacterium Ochrobactrum sp. FDT5 was isolated and found to have microcystin-LR (MC-LR) degradation capacity, which could be enhanced by a domestication process. The FDT5 cell density, MC-LR initial concentration, temperature, and pH on the degradation of MC-LR were investigated. The results indicated that the initial cell density of FDT5 and the initial concentration of MC-LR could influence MC-LR degradation. The optimum conditions were under the temperature of 35°C with pH of 7.0. After FDT5 was exposed to MC-LR for 2 days, FDT5 cells produced active cellular components that degraded MC-LR. These cellular components were heat-inactivated and removed when FDT5 cells were removed by filtration.


Assuntos
Microcistinas/metabolismo , Ochrobactrum/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Toxinas Marinhas , Microcistinas/análise , Ochrobactrum/classificação , Ochrobactrum/genética , Esgotos/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos , Águas Residuárias/microbiologia , Poluentes Químicos da Água/análise , Purificação da Água/métodos
13.
Talanta ; 278: 126435, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38924986

RESUMO

Wastewater-based epidemiology (WBE) is a powerful tool for early warning of infectious disease outbreaks. Hence, a rapid and portable pathogen monitoring system is urgent needed for on-site detection. In this work, we first reported synthesis of an artificial modulated wide-spectrum bacteria capture nanoparticle (Arg-CSP@UiO@Fe3O4). Arginine-modified phosphorylated chitosan (Arg-CSP) coating could provide strongly positive charged guanidinium group for pathogen interaction by electrostatic attraction, and UiO-66-NH2 layer could help Arg-CSP graft onto Fe3O4 magnetic particles. The capture efficiency of Arg-CSP@UiO@Fe3O4 reached 92.2 % and 97.3 % for Escherichia coli (E.coli) and Staphylococcus epidermidis (S.epidermidis)within 40 min, in 10 mL sample. To prevent pathogen degradation in sewage, a portable nucleic acid extraction-free method was also developed. UiO-66-NH2 could disintegrate in buffer with high concentration of PO43- for bacterium desorption, and then nucleic acid of the bacteria was released by heating. The DNA template concentration obtained by this method was 779.28 times higher than that of the direct thermal lysis product and 8.63 times higher than that of the commercial kit. Afterwards, multiple detection of bacteria was realized by loop-mediated isothermal amplification (LAMP). Artificial regulated pathogen desorption could prevent non-specific adsorption of nucleic acid by nanoparticles. The detection limit of Arg-CSP@UiO@Fe3O4-LAMP method was 80 cfu/mL for E.coli and 300 cfu/mL for S.epidermidis. The accuracy and reliability of the method was validated by spiked sewage samples. In conclusion, this bio-monitoring system was able to detect multiple bacteria in environment conveniently and have good potential to become an alternative solution for rapid on-site pathogen detection.

14.
ACS Sens ; 9(3): 1178-1187, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38437216

RESUMO

Undoubtedly, a deep understanding of PM2.5-induced tumor metastasis at the molecular level can contribute to improving the therapeutic effects of related diseases. However, the underlying molecular mechanism of fine particle exposure through long noncoding RNA (lncRNA) regulation in autophagy and, ultimately, lung cancer (LC) metastasis remains elusive; on the other hand, the related monitoring sensor platform used to investigate autophagy and cell migration is lacking. Herein, this study performed an air-liquid interface microfluidic monitoring sensor (AIMMS) platform to analyze human bronchial epithelial cells after PM2.5 stimulation. The multiomics analysis [RNA sequencing (RNA-seq) on lncRNA and mRNA expressions separately] showed that MALAT1 was highly expressed in the PM2.5 treatment group. Furthermore, RNA-seq analysis demonstrated that autophagy-related pathways were activated. Notably, the main mRNAs associated with autophagy regulation, including ATG4D, ATG12, ATG7, and ATG3, were upregulated. Inhibition or downregulation of MALAT1 inhibited autophagy via the ATG4D/ATG12/ATG7/ATG3 pathway after PM2.5 exposure and ultimately suppressed LC metastasis. Thus, based on the AIMMS platform, we found that MALAT1 might become a promising therapeutic target. Furthermore, this low-cost AIMMS system as a fluorescence sensor integrated with the cell-monitor module could be employed to study LC migration after PM2.5 exposure. With the fluorescence cell-monitoring module, the platform could be used to observe the migration of LC cells and construct the tumor metastasis model. In the future, several fluorescence probes, including nanoprobes, could be used in the AIMMS platform to investigate many other biological processes, especially cell interaction and migration, in the fields of toxicology and pharmacology.


Assuntos
Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Microfluídica , Neoplasias Pulmonares/genética , Material Particulado/toxicidade , Autofagia
15.
Anal Chem ; 85(10): 5255-62, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23590462

RESUMO

Highly efficient capture and enrichment is always the key for rapid analysis of airborne pathogens. Herein we report a simple microfluidic device which is capable of fast and efficient airborne bacteria capture and enrichment. The device was validated with Escherichia coli (E. coli) and Mycobacterium smegmatis. The results showed that the efficiency can reach close to 100% in 9 min. Compared with the traditional sediment method, there is also great improvement with capture limit. In addition, various flow rate and channel lengths have been investigated to obtain the optimized condition. The high capture and enrichment might be due to the chaotic vortex flow created in the microfluidic channel by the staggered herringbone mixer (SHM) structure, which is also confirmed with flow dynamic mimicking. The device is fabricated from polydimethylsiloxane (PDMS), simple, cheap, and disposable, perfect for field application, especially in developing countries with very limited modern instruments.


Assuntos
Microbiologia do Ar , Bactérias/isolamento & purificação , Técnicas Analíticas Microfluídicas/instrumentação , Escherichia coli/isolamento & purificação , Limite de Detecção , Microscopia Confocal , Mycobacterium smegmatis/isolamento & purificação , Tamanho da Partícula , Espectrometria de Fluorescência , Fatores de Tempo
16.
Biomed Microdevices ; 15(6): 949-57, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23832621

RESUMO

A microfluidic immunoassay is successfully developed for rapid analysis of cotinine saliva samples, which is a metabolite of nicotine and is widely used as a biomarker to evaluate the smoking status and exposure to tobacco smoke. The core microfluidic chip is fabricated by polydimethylsiloxane (PDMS) with standard soft lithography. Each chip is capable of eight parallel analyses of cotinine samples. The analyses can be completed within 40 min with 12 µl sample consumption. The linear detection range is 1 ~ 250 ng/ml and the minimum detectable concentration is 1 ng/ml respectively. The correlation coefficient of the calibration curve established from standard samples is 0.9989. The immunoassay was also validated by real saliva samples, and the results showed good reproducibility and accuracy. All the results were confirmed with traditional ELISA measurements. The result from microfluidic chip device and ELISA kits showed good correspondence, and the correlation coefficients are higher than 0.99. Compared with traditional technique, this microfluidic immunoassay is more economic, rapid, simple and sensitive, perfect for on-site cotinine measurements as well as for the evaluation of the exposure to tobacco smoking. Moreover, this immunoassay has potential to be applied in the analysis of other biomarkers in human saliva samples.


Assuntos
Cotinina/análise , Imunoensaio/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Saliva/química , Desenho de Equipamento , Humanos , Fumar , Espectrometria de Fluorescência , Fatores de Tempo
17.
Sci Total Environ ; 857(Pt 1): 159306, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36216064

RESUMO

As a new type of environmental pollutants, micro/nano plastics (MPs/NPs) derived from plastic products are commonly contact in daily life and lead to some serious health issues. The toxicity effects of MPs/NPs on the human body have aroused wide concerns. Although MPs/NPs have been reported to be transmitted into the kidney and reproductive organs, the molecular mechanisms of MPs/NPs toxicity remain unclear due to the lack of a physiologically relevant organ-organ linking platform in vitro. Here, we present a kidney-testis microfluidic platform (KTP) with NPs exposure that enables the communication of kidney and testis chambers and reproduces endothelium-linked chambers to simulate the state in vivo. The function of KTP was assessed by cell counting kit (CCK-8), tight junction protein claudin-2 and glucose consumption. Results revealed that MPs/NPs entered the kidney and testis via endocytosis. Immunofluorescence and ELISA analysis were performed on KTP at 200 µg/mL PS-NP to identify the dysregulated proteins on cancer-related signaling pathways, including the MAPK signaling pathway (RTK, RAS, ERK, JNK, P38, NRF2, TNF-α, and TNF-α-R) and the PI3K-AKT signaling pathway (PI3K, AKT, MDM2, P53, and ΒΑD). This multi-organ platform (KTP) contributes to clarifying cancer pathways triggered by MPs/NPs exposure and provides a promising method for assessing diseases induced by environmental pollutants.


Assuntos
Poluentes Ambientais , Neoplasias , Poluentes Químicos da Água , Masculino , Humanos , Poliestirenos/toxicidade , Microplásticos , Testículo , Poluentes Químicos da Água/análise , Microfluídica , Fator de Necrose Tumoral alfa , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt/farmacologia , Rim , Poluentes Ambientais/toxicidade , Poluentes Ambientais/análise , Transdução de Sinais
18.
Front Microbiol ; 14: 1236599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692407

RESUMO

Objectives: Lipoarabinomannan (LAM), an abundant cell wall glycolipid of mycobacteria including Mycobacterium tuberculosis (Mtb), is a promising TB diagnostic marker. The current commercially available urine LAM assays are not sufficiently sensitive, and more novel detection strategies are urgently needed to fill the current diagnostic gap. Methods: A proteinase K-pretreated Concanavalin A (ConA)-based ELISA assay was developed. Diagnostic performance was assessed by several bacterial strains and clinical urine samples. Results: The limit of detection (LoD) of the assay against ManLAM was 6 ng/ml. The assay reacted strongly to Mtb H37Rv and M. bovis BCG, intermediately to M. smegmatis mc2155, and weakly to four non-mycobacteria pathogens. This method could distinguish TB patients from healthy controls (HCs) and close contacts (CCs) in 71 urine samples treated with proteinase K, which increases urine LAM antibody reactiveness. In TB+HIV+ and TB+HIV- patients, the sensitivity was 43.8 and 37.5%, respectively, while the specificity was 100.0%. The areas under ROC curves (AUCs) were 0.74 and 0.82, respectively. Conclusion: This study implies that ConA can be paired with antibodies to detect LAM. Proteinase K treatment could effectively enhance the sensitivity by restoring the reactiveness of antibodies to LAM.

19.
Front Microbiol ; 14: 1157403, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200917

RESUMO

Background: Urinary tract infections (UTIs) are some of the most common bacterial infections in the world. Nevertheless, as uncomplicated UTIs are treated empirically without culturing the urine, adequate knowledge of the resistance pattern of uropathogens is essential. Conventional urine culture and identification take at least 2 days. Here, we developed a platform based on LAMP and centrifugal disk system (LCD) to simultaneously detect the main pathogens and antibiotic resistant genes (ARGs) of urgent concern multidrug-resistant among UTIs. Methods: We designed specific primers to detect the target genes above and evaluated their sensitivity and specificity. We also assessed the result of our preload LCD platform on 645 urine specimens with a conventional culturing method and Sanger sequencing. Results: The results obtained with the 645 clinical samples indicated that the platform has high specificity (0.988-1) and sensitivity (0.904-1) for the studied pathogens and ARGs. Moreover, the kappa value of all pathogens was more than 0.75, revealing an excellent agreement between the LCD and culture method. Compared to phenotypic tests, the LCD platform is a practical and fast detection approach for methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococci, carbapenem-resistant Enterobacteriaceae, carbapenem-resistant Acinetobacter, carbapenem-resistant Pseudomonas aeruginosa (kappa value of all >0.75), and non-extended-spectrum ß-lactamase producers. Conclusion: We developed a detection platform that has high accuracy and that meets the need for rapid diagnosis, which can be completed within 1.5 h from specimen collection. It may be a powerful tool for evidence-based UTIs diagnosis, which has essential support for the rational use of antibiotics. More high-quality clinical studies are required to prove the effectiveness of our platform.

20.
J Biosaf Biosecur ; 4(1): 54-58, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35252802

RESUMO

Nucleic acid detection, widely used in clinical diagnosis, biological analysis, and environmental monitoring, is of great significance for disease diagnosis and basic research. With the outbreak of COVID-19, the demand for fast and high-throughput nucleic acid detection from large numbers of samples has increased sharply. Automated nucleic acid detection systems can meet these needs, and also play important roles in disease screening and infectious disease prevention and control. In this review, we introduce and compare the current mainstream nucleic acid automatic detection instruments and equipment, then discuss the future demands of nucleic acid detection.

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