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1.
Anal Methods ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690766

RESUMO

A concise and rapid detection method for Mycoplasma pneumoniae is urgently required due to its severe impact on human health. To meet such a need, this study proposed and constructed an innovative point-of-care testing (POCT) platform that consists of a hydrogen ion-selective loop-mediated isothermal amplification (H+-LAMP) sensor and an electrochemical detection device. The H+-LAMP sensor successfully integrated the working and reference electrodes and converted the H+ generated during the LAMP process into an electrochemical signal. High sensitivity and stability for pathogen detection were also achieved by treating the working electrode with an electrodeposited polyaniline solid contact layer and by using an ion-selective membrane. As a result, the sensor shows a sensitivity of 68.26 mV per pH, a response time of less than 2 s, and a potential drift of less than 5 mV within one hour, which well meets the urgent need. The results also demonstrated that the detection limit for Mycoplasma pneumoniae was lowered to 1 copy per µL, the nucleic acid extraction and detection process could be completed in 30 minutes, and the impact of interfering ions on the sensor was negligible. Validation with 20 clinical samples yielded satisfactory results. More importantly, the storage lifespan of such an electrochemical sensor is over seven days, which is a great advantage for on-site pathogen detection. Therefore, the hydrogen ion-selective sensor constructed in this investigation is particularly suitable as a core component for instant pathogen detection platforms.

2.
Anal Bioanal Chem ; 416(13): 3161-3171, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38558309

RESUMO

Since RNA is an important biomarker of many infectious pathogens, RNA detection of pathogenic organisms is crucial for disease diagnosis and environmental and food safety. By simulating the base mismatch during DNA replication, this study presents a novel three-way junction structure-mediated reverse transcription-free exponential amplification reaction (3WJ-RTF-EXPAR) for the rapid and sensitive detection of pathogen RNA. The target RNA served as a switch to initiate the reaction by forming a three-way junction (3WJ) structure with the ex-trigger strand and the ex-primer strand. The generated trigger strand could be significantly amplified through EXPAR to open the stem-loop structure of the molecular beacon to emit fluorescence signal. The proofreading activity of Vent DNA polymerase, in combination with the unique structure of 2+1 bases at the 3'-end of the ex-primer strand, could enhance the role of target RNA as a reaction switch to reduce non-specific amplification and ensure excellent specificity to differentiate target pathogen from those causing similar symptoms. Furthermore, detection of target RNA showed a detection limit of 1.0×104 copies/mL, while the time consumption was only 20 min, outperforming qRT-LAMP and qRT-PCR, the most commonly used RNA detection methods in clinical practice. All those indicates the great application prospects of this method in clinical diagnostic.


Assuntos
Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/análise , RNA Viral/genética , RNA Bacteriano/análise , RNA Bacteriano/genética , Humanos
3.
Talanta ; 274: 126007, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583331

RESUMO

Hypoxanthine (Hx), produced by adenosine triphosphate (ATP) metabolism, is a valuable indicator that determines the quality and degradation status of meat products and is also an important biochemical marker to certain diseases such as gout. The rapid emergence of paper-based enzyme biosensors has already revolutionized its on-site determination. But it is still limited by the complex patterning and fabrication, unstable enzyme and uneven coloration. This work aims to develop an eco-friendly method to construct engineered paper microfluidic, which seeks to produce reaction and non-reaction zones without any patterning procedure. Chito-oligosaccharide (COS), derived from shrimp shells, was used to modify nitrocellulose membranes and immobilize xanthine oxidase (XOD) and chromogenic agent of nitro blue tetrazolium chloride (NBT). After modification, micro fluids could converge into the modification area and Hx could be detected by XOD-catalyzed conversion. Due to the positively charged cationic basic properties of COS, the enzyme storage stability and the color homogeneity could be greatly strengthened through the electrostatic attraction between COS and XOD and formazan product. The detection limit (LOD) is 2.30 µM; the linear range is 0.05-0.35 mM; the complete test time can be as short as 5 min. The COS-based biosensor shows high specificity and can be used directly for Hx in complex samples such as fish and shrimp samples, and different broths. This biosensor is eco-friendly, nontechnical, economical and therefore a compelling platform for on-site or home-based detection of food freshness.


Assuntos
Técnicas Biossensoriais , Colódio , Hipoxantina , Oligossacarídeos , Xantina Oxidase , Animais , Oligossacarídeos/química , Oligossacarídeos/análise , Técnicas Biossensoriais/métodos , Hipoxantina/análise , Hipoxantina/química , Colódio/química , Xantina Oxidase/química , Xantina Oxidase/metabolismo , Peixes , Quitina/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Química Verde/métodos , Propriedades de Superfície , Limite de Detecção
4.
Anticancer Drugs ; 35(6): 548-555, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502829

RESUMO

Shwachman-Diamond syndrome (SDS) is an autosomal recessive genetic disease, which is prone to transform into myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). TP53 mutation is a driving factor involved in the transformation of SDS into MDS/AML, and in the evolution of MDS to AML. Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is the only curable approach, however, challenge remains regarding the balance between efficacy and the high risk from treatment-related toxicity and mortality to achieve temporary disease control before transplantation to gain time and opportunities for transplantation. At present, pre-transplant bridging therapy has emerged as one of the important options with improved efficacy, reduced tumor burden, and less treatment-related toxicity. Here we reported azacitidine combined with venetoclax was used as pre-transplant bridging regimen in a TP53-mutant AML-MR case developed from SDS. He achieved complete remission with incomplete recovery and proceeded to Allo-HSCT. We hope to provide some evidence and insight for in-depth research and clinical treatment by presenting this case.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Azacitidina , Compostos Bicíclicos Heterocíclicos com Pontes , Leucemia Mieloide Aguda , Mutação , Sulfonamidas , Proteína Supressora de Tumor p53 , Humanos , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Azacitidina/uso terapêutico , Azacitidina/administração & dosagem , Sulfonamidas/uso terapêutico , Sulfonamidas/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Proteína Supressora de Tumor p53/genética , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética
5.
Anal Methods ; 16(6): 892-898, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38247331

RESUMO

Staphylococcus aureus is one of the most common foodborne pathogens that can cause serious food poisoning and infectious diseases in humans. Standard identification approaches include nucleic acid amplification, but current amplification tools suffer from low amplification efficiency, resulting in the risk of low sensitivity and long detection time. Herein, boron nitride nanoplates (BNNPs) were chosen as an additive for enhancing the sensitivity and rapidity of strand exchange amplification (SEA), thereby successfully expanding the application of nucleic acid detection for detecting Staphylococcus aureus in food samples. As a result, SEA based on boron nitride nanoplates (BNNP-SEA) was employed for sensitive and rapid detection of foodborne pathogen Staphylococcus aureus. Compared with classical SEA, the BNNP-based SEA assay was more than 10-fold sensitive, and the detection time was reduced by 15 minutes. The optimized BNNP-based SEA shows a wide linear range from 40 pg to 50 ng in a diluted solution of the target DNA with a low detection limit of 40 pg. Moreover, the BNNP-based SEA achieves the quantitative detection of Staphylococcus aureus in different food samples (pork, beef, mutton, duck, milk and shrimp). In contrast to the classical SEA, the BNNP-based SEA method enabled sensitive and rapid detection of Staphylococcus aureus in the above food samples at concentrations as low as 5 × 103 CFU mL-1. The BNNP-based SEA assay is specific, sensitive and reliable, offering a valuable diagnostic technology for routine analysis in food safety research.


Assuntos
Compostos de Boro , Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Animais , Bovinos , Staphylococcus aureus/genética , Sensibilidade e Especificidade , Microbiologia de Alimentos , DNA
6.
Anal Biochem ; 687: 115456, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38161043

RESUMO

In this study, we developed colony and bacterial LAMP, which directly use bacterial colony and bacterial culture as the templates without DNA extraction for rapid and simple detection of bacteria. The end-point readouts were determined by naked eye under ultraviolet light, and real-time fluorescence curve was also used to confirm that the sensitivity of this method to Salmonella typhimurium and Bacillus cereus was 102 and 103 CFU/reaction, respectively. Results presented here provide alternative methods for colony and bacterial PCR that can greatly contribute to reliable and cost-effective diagnosis in resource-poor settings.


Assuntos
Bactérias , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA Bacteriano/genética
7.
Anal Chem ; 95(49): 18249-18257, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38041626

RESUMO

RNA-based detection of pathogenic organisms is an emerging field of research that is crucial for disease diagnosis and environmental and food safety. By rationally engineering an RNA-DNA tandem (RDT) structural template, we proposed a novel RNase H-based isothermal exponential amplification (RH-IEA) reaction to rapidly identify long-stranded RNA. In this strategy, the rigid and compact RDT template selectively recognized the target RNA and formed a stable hybrid with it. Upon site-specific cleavage of RNase H, the 3' overhang of the target RNA was cut off, and a free hydroxyl end at the hydrolysis site was generated to trigger an exponential amplification reaction (EXPAR). This method maintained the high efficiency and rapid amplification kinetics of EXPAR. As a result, the RH-IEA strategy was able to sensitively and specifically detect the characteristic sequence of Escherichia coli O157:H7 RNA, with a detection sensitivity of 1 fg/µL. Besides, the RDT template can be used as an RNA protector to prevent specific segments of the target RNA from being degraded by RNase enzymes, allowing the sample to be stored at room temperature for a long time. With this advantage, the practicality of RH-IEA will be more flexible than the reverse transcription polymerase chain reaction. It was successfully applied in the identification of E. coli O157:H7 in milk with a minimum detection concentration of 1.0 × 102 CFU/mL. Therefore, the RH-IEA method will serve as a powerful tool for detecting long-stranded RNA and will also shed light on the pathogen detection in food safety and molecular diagnosis.


Assuntos
Escherichia coli O157 , RNA , RNA/genética , Ribonuclease H , Escherichia coli O157/genética
8.
Anal Chim Acta ; 1280: 341851, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858548

RESUMO

BACKGROUND: Nucleic acid testing based on DNA amplification is gradually entering people's modern life for clinical diagnosis, food safety monitoring and infectious disease prevention. Polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) are the most powerful techniques that have been the gold standard for quantitative nucleic acid analysis. However, the high nonspecific amplification rate caused by the formation of primer dimers, hairpin structures and mismatched hybridization severely restricts their real-world applications. It is highly desirable to explore a way for improving the specificity and sensitivity of PCR and LAMP assays. RESULTS: In this work, we demonstrated that a nanomaterial boron nitride nanoplate (BNNP), due to its unique surface properties, can interact with the main components of the amplification reaction, such as single stranded primers and Bst DNA polymerase, and increase the thermal conductivity of the solution. As a result, the presence of BNNPs dramatically improved the specificity of PCR and LAMP. And BNNPs maintained the specificity even after five rounds of PCR. Moreover, the sensitivity of LAMP was also enhanced by BNNPs, and the detection limit of BNNP-based LAMP was two orders of magnitude lower than that of classical LAMP. Then the BNNP-based LAMP was applied to detect Vibrio parahaemolyticus in contaminated seafood samples with high specificity and a 10-fold increase in sensitivity. SIGNIFICANCE: This is the first systematic demonstration of BNNPs as a promising additive to enhance the efficiency and fidelity of PCR and LAMP amplification reactions, thereby greatly expanding the application of nucleic acid detection in a wide range of laboratory and clinical settings.


Assuntos
Ácidos Nucleicos , Vibrio parahaemolyticus , Humanos , Vibrio parahaemolyticus/genética , Sensibilidade e Especificidade , Técnicas de Amplificação de Ácido Nucleico/métodos
9.
Cell Mol Biol (Noisy-le-grand) ; 69(8): 221-225, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37715381

RESUMO

Lung cancer remains the leading cause of cancer morbidity and mortality worldwide, and over-diagnosis causes various unnecessary losses in patients' lives and health. How to more effectively screen lung cancer patients and their potential prognostic risk become the focus of our current study. By analyzing the LUAD expression profile in The Cancer Genome Atlas (TCGA), we constructed a weighted gene co-expression network using differentially expressed genes (DEGs) to find the key modules and pivotal genes. A COX proportional risk regression model based on the least absolute shrinkage and selection operator (LASSO) was used to assess the predictive value of the model for the prognosis of LUAD patients. A total of 4107 up-regulated DEGs and 2022 down-regulated DEGs were identified in this study, and enrichment analysis showed that these analyzes were associated with the extracellular matrix of cells and adhesion. Ten gene markers consisting of LDHA, TOP2A, UBE2C, TYMS, TRIP13, EXO1, TTK, TPX2, ZWINT, and UHRF1 were established by extracting the central genes in the key modules, and the upregulation of these genes was accompanied by an increased prognostic risk of patients. Among them, high expression of LDHA, TRIP13, and TTK in LUAD was associated with shorter overall survival and could be used as independent prognostic factors to participate in metabolic processes such as tumor NAD. The present study provides a powerful molecular target for the study of LUAD prognosis and provides a theoretical basis for the diagnosis and treatment of LUAD and the development of targeted inhibitors.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Biologia Computacional , Matriz Extracelular , Proteínas Estimuladoras de Ligação a CCAAT , Ubiquitina-Proteína Ligases , ATPases Associadas a Diversas Atividades Celulares , Proteínas de Ciclo Celular
10.
BMC Ophthalmol ; 23(1): 338, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37507767

RESUMO

BACKGROUND: To investigate the role of neutrophils in corneal nerve regeneration. METHODS: A mouse model simulating corneal nerve injury was established and samples from corneal scraping with and without neutrophil closure were collected. These samples were used for corneal nerve staining, ribonucleic acid sequencing, and bioinformatics. Differential expression analysis was used to perform enrichment analysis to identify any significant differences between these two groups. The differential genes were then intersected with neutrophil-associated genes and a protein-protein interaction network was constructed using the intersected genes. The immune infiltration between the two groups was examined along with the immune cell variation between the high and low gene expression groups. RESULTS: Neutrophil removal delays corneal epithelial and nerve regeneration. A total of 546 differential genes and 980 neutrophil-associated genes, with 27 genes common to both sets were obtained. Molecular Complex Detection analysis yielded five key genes, namely integrin subunit beta 2 (ITGB2), matrix metallopeptidase 9 (MMP9), epidermal growth factor (EGF), serpin family E member 1 (SERPINE1), and plasminogen activator urokinase receptor (PLAUR). Among these genes, ITGB2, SERPINE1, and PLAUR exhibited increased expression in the neutrophil-confined group, while MMP9 and EGF showed decreased expression, with MMP9 and EGF displaying a more significant difference. Immune infiltration was also observed between the two groups, revealing significant differences in the infiltration of M0 macrophages, activated mast cells, and neutrophils. Moreover, the neutrophil levels were lower in the groups with low MMP9 and EGF expressions and higher in the high-expression group. CONCLUSION: Neutrophil confinement might significantly affect the MMP9 and EGF expression levels. Strategies to inhibit MMP9 could potentially yield therapeutic benefits.


Assuntos
Lesões da Córnea , Neutrófilos , Animais , Camundongos , Fator de Crescimento Epidérmico , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Córnea/metabolismo , Regeneração Nervosa
11.
Anal Methods ; 15(27): 3325-3332, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37379082

RESUMO

Electrochemical biosensing is a sensitive strategy widely used in the field of nucleic acid detection. However, electrochemical biosensors generally involve time-consuming and labor-intensive probe immobilization processes. In this study, an electrochemical DNA biosensor based on homogeneous hybridization in solution was designed for nucleic acid detection without probe immobilization, which is different from most biosensors. The capture probe, detection probe, and target DNA were hybridized rapidly under an electric field to form a "sandwich" structure within 90 s, and the "sandwich" hybrid could be specifically coupled to streptavidin-modified magnetic beads within 5 min. Finally, the magnetic beads were enriched by using polypyrrole (PPy)/carbon nanotube (CNT)-modified magnetic electrodes and the signal was detected by differential pulse voltammetry (DPV). The magnetic biosensor constructed in this study could detect targets over a good linear dynamic range spanning 100 pM to 100 nM in 400 s, while those involving conventional hybridization methods always take 2 h or more. Because of the specific binding of streptavidin and biotin, this strategy showed high specificity. Taken together, the homogenous hybridization magnetic biosensor constructed with electric field assistance presents a potential diagnostic method for rapid DNA detection and provides a new idea for rapid nucleic acid detection in clinical practice.


Assuntos
Técnicas Biossensoriais , Polímeros , Estreptavidina/química , Pirróis , DNA/química , Eletricidade , Técnicas Biossensoriais/métodos
12.
Analyst ; 148(9): 1970-1977, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37022124

RESUMO

Staphylococcus aureus is a common foodborne pathogen that causes food poisoning and infectious diseases in humans and animals. Rapid detection of S. aureus with high sensitivity is of great significance to prevent the spread of this pathogen. In this study, we developed a staggered strand exchange amplification (SSEA) method by refining denaturation bubble-mediated strand exchange amplification (SEA) to detect S. aureus at a constant temperature with high specificity and efficiency. This method employs a DNA polymerase and two sets of forward and reverse primers arranged in tandem that invade denaturation bubbles of double-stranded DNA. In comparison, the sensitivity of SSEA was 20 times that of SEA. Subsequently, magnetic bead (MB)-based DNA extraction was introduced into SSEA to establish an all-in-one SSEA platform that incorporated sample processing, amplification and detection in a single tube. The use of MBs further enhanced the sensitivity of SSEA by two orders of magnitude. Specificity tests showed that the all-in-one SSEA could specifically identify S. aureus and had no cross-reaction with other common foodborne pathogens. For artificially spiked meat samples, the method could detect 1.0 × 102 CFU g-1S. aureus in pork and 1.0 × 103 CFU g-1 in either duck or scallop samples without a bacterial enrichment step. The entire assay can be completed sample-to-answer within 1 h. Thus, we believe that this easy-to-operate diagnostic platform enables sensitive and accurate detection of S. aureus and holds great promise for the food safety industry.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Animais , Staphylococcus aureus/genética , Microbiologia de Alimentos , Sensibilidade e Especificidade , Separação Imunomagnética
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 296: 122648, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36966729

RESUMO

The deleterious toxicity of Hg2+ on ecological and biological system makes it crucial for the precise monitoring of Hg2+. Herein, we prepared a novel "turn-on" chemosensor N'-(4-(methylthio)butan-2-ylidene) rhodamine B hydrazide (denoted as MTRH) by a simple two-step reaction. MTRH exhibited an ultra-low detection limit (LOD) in fluorescence measurement of Hg2+ in pure aqueous media, which was estimated to be 1.3 × 10-9 mol·L-1. Moreover, the proposed chemosensor holds the ability of visualizing Hg2+ by the distinct color change of the solution. The corresponding recognition mechanism was investigated by Job's plots, mass spectrometry and DFT calculation analysis. Importantly, the characteristics such as high sensitivity, low cytotoxicity and good biocompatibility of MTRH exhibited in the application of detecting Hg2+ in real water sample and bioimaging of intracellular Hg2+ prove that MTRH is a promising tool to evaluate the levels of Hg2+ in complex biological systems.


Assuntos
Mercúrio , Mercúrio/análise , Água , Espectrometria de Massas , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos
14.
Anal Methods ; 15(15): 1915-1922, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37000537

RESUMO

RNA has been recognized as an important biomarker of many infectious pathogens; thus, sensitive, simple and rapid detection of RNA is urgently required for the control of epidemics. Herein, we report an ultrafast ligation-dependent RNA transcription amplification assay with high sensitivity and specificity for real-time detection of SARS-CoV-2 in real clinical samples, termed splint-based cascade transcription amplification (SCAN). Target RNA is first recognized by two DNA probes, which are then ligated together by SplintR, followed by the binding of the T7 promotor and T7 RNA polymerase to the ligated probe and the start of the transcription process. By introducing a vesicular stomatitis virus (VSV) terminator in the ligated probe, large amounts of RNA transcripts are rapidly produced within 10 min, which then directly hybridize with molecular beacons (MBs) and trigger the conformational switch of the MBs to generate a fluorescence signal that can be monitored in real time. The SCAN assay, which can be completed within 30-50 min, has a limit of detection of 104 copies per mL, while exhibiting high specificity to distinguish the target pathogen from those causing similar syndromes. More importantly, the results of SCAN for SARS-CoV-2 detection in clinical samples display great agreement with the most used qRT-PCR and qRT-LAMP, indicating great potential in the diagnosis of pathogens in clinical practice.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase em Tempo Real , RNA
15.
Chem Commun (Camb) ; 59(32): 4786-4789, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37000571

RESUMO

Here, we established a two-stage isothermal amplification method comprising strand exchange amplification and hyperbranched rolling circle amplification, which only employed one DNA polymerase and was performed in a single closed tube at a constant temperature, providing a promising signal amplification strategy for accurate and rapid pathogen detection in the clinic.


Assuntos
Ácidos Nucleicos , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA Polimerase Dirigida por DNA , Temperatura
16.
Curr Microbiol ; 80(3): 97, 2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36738393

RESUMO

Combined use of the present antimicrobial drugs has been proved to be an alternative approach for antimicrobial agents' development since the co-existed of the drugs working in different mechanism have been demonstrated potentially enhance their antimicrobial activity. In this work, antibacterial and antifungal activity of the cetylpyridinium chloride (CPC)/chlorhexidine acetate (CHA) combination was evaluated for the first time, while a universal concentration for the rapid killing of gram-positive/gram-negative bacteria and fungi was also proposed. The minimum inhibitory concentrations (MIC) of CPC and CHA used alone or in combination were first measured, showing that the combined treatment decreased the MIC against tested gram-positive/gram-negative bacteria and fungi to 1/8-1/2. Growth curve assays demonstrated CPC and CHA had dynamic combined effects against the tested microorganisms at the concentration equal to MIC. Besides, combined use of these two drugs could also enhance their biocidal activity, which was illustrated by fluorescence microscopy and SEM images, as well as soluble protein measurement. More importantly, in vitro acute eye and skin irritation tests showed short-term contact with CPC/CHA combination would not cause any damage to mammalian mucosa and skin. In a word, CPC/CHA combination exhibited broad-spectrum antibacterial and antifungal activity against tested gram-positive/gram-negative bacteria and fungi while without any acute irritation to mammalian mucosa and skin, providing a new perspective on the selection of personal disinfectants.


Assuntos
Anti-Infecciosos , Clorexidina , Clorexidina/farmacologia , Cetilpiridínio/farmacologia , Antifúngicos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias Gram-Positivas , Bactérias Gram-Negativas , Bactérias , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Fungos
17.
Anal Methods ; 15(5): 655-662, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36655424

RESUMO

Vibrio parahaemolyticus infectious diseases caused by seafood contamination may be life-threatening to people with weak immunity. The detection of the Vibrio parahaemolyticus pathogen in aquatic foods is critical for reducing the outbreak of human Vibrio parahaemolyticus-associated diseases. In this study, a highly sensitive, specific, and time-saving real-time narrow thermal-cycling amplification detection method was developed based on accelerated strand exchange amplification (ASEA). It can detect cultured Vibrio parahaemolyticus at concentrations as low as 25 CFU mL-1. In addition, for artificially spiked scallop meat, the detection limit was 1.8 × 103 CFU g-1 without pre-culture and 18 CFU g-1 of initial inoculum after 3 h enrichment. The whole assay, starting from DNA extraction, can be completed within 20 min. The ASEA detection method established in this study is an effective tool for the rapid detection of Vibrio parahaemolyticus strains in a large number of seafood samples.


Assuntos
Doenças Transmitidas por Alimentos , Vibrioses , Vibrio parahaemolyticus , Humanos , Vibrio parahaemolyticus/genética , Sensibilidade e Especificidade , Alimentos Marinhos , Vibrioses/diagnóstico
18.
Anal Bioanal Chem ; 415(3): 427-438, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36385304

RESUMO

Nucleic acid amplification tests (NAATs) have become an attractive approach for pathogen detection, and obtaining high-quality nucleic acid extracts from biological samples plays a critical role in ensuring accurate NAATs. In this work, we established an elution-free magnetic bead (MB)-based method by introducing polyethylene-polypropylene glycol (PEPPG) F68 in lysis buffer and using NaOH solution instead of alcohols as the washing buffer for rapid nucleic acid extraction from multiple types of biological samples, including nasopharyngeal swabs, serum, milk, and pork, which bypassed the nucleic acid elution step and allowed the nucleic acid/MB composite to be directly used as the template for amplification reactions. The entire extraction process was able to be completed in approximately 7 min. Even though the nucleic acid/MB composite could not be used for quantitative real-time PCR (qPCR) assays, this elution-free MB-based method significantly improved the sensitivity of the loop-mediated isothermal amplification (LAMP) assay. The sensitivity of the quantitative real-time LAMP (qLAMP) assays combined with this elution-free MB-based method showed an improvement of one to three orders of magnitude compared with qLAMP or qPCR assays combined with the traditional MB-based method. In addition to manual operation, like the traditional MB-based method, this universal, rapid, and facile nucleic acid extraction method also has potential for integration into automated robotic processing, making it particularly suitable for the establishment of an analysis platform for ultrafast and sensitive pathogen detection in various biological samples both in centralized laboratories and at remote sites.


Assuntos
Ácidos Nucleicos , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fenômenos Magnéticos , Sensibilidade e Especificidade
19.
J Pharm Biomed Anal ; 224: 115190, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36463769

RESUMO

Herein, we developed a facile integrated Mycoplasma pneumoniae diagnosis platform by combining amino-modified silica membrane (AMSM)-based nucleic acids fast extraction and enrichment with colorimetric isothermal amplification detection. AMSM demonstrates a strong ability to capture and enrich nucleic acids in complicated biological matrices, and the purified AMSM/nucleic acids composite could be directly used to perform isothermal amplification including denaturation bubble-mediated strand exchange amplification (SEA) and loop-mediated isothermal amplification (LAMP) reactions. Through comparing clinical specimens, excellent performance of AMSM-based SEA assay with 93.33% sensitivity and 100% specificity relative to real-time PCR was observed, and for AMSM-based LAMP was 96.67% and 100%, respectively. The diagnostic procedure could be completed within 55 min, and the colorimetric-based visual result further alleviates the use of sophisticated equipment. The proposed approach possesses great potential as a simple and time-saving alternative for point-of-care testing (POCT) of M. pneumoniae in resource-limited regions.


Assuntos
Mycoplasma pneumoniae , Ácidos Nucleicos , Mycoplasma pneumoniae/genética , Sensibilidade e Especificidade , Testes Imediatos , DNA
20.
Anal Chim Acta ; 1238: 340639, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36464451

RESUMO

The false-negative result of nucleic acid testing is an important cause of continued spread of COVID-19, while SARS-CoV-2 RNA degradation during transportation and nucleic acid extraction can lead to false-negative results. Here, we investigated that single-walled carbon nanotubes (SCNTs) could protect RNA from degradation for at least 4 days at room temperature. By constructing magnetism-functionalized SCNTs (MSCNTs), we developed a method that enabled protection and simple extraction of SARS-CoV-2 RNA, and the RNA-bound MSCNTs can be directly used for reverse transcription polymerase chain reaction (RT-qPCR) detection. The experimental results showed that 1 µg of MSCNTs adsorbed up to 24 ng of RNA. Notably, the MSCNTs-based method for extracting SARS-CoV-2 RNA from simulated nasopharyngeal swabs and saliva samples with mean recovery rates of 103% and 106% improved the sensitivity of RT-qPCR detection by 8-32 fold in comparison to current common methods. This improvement was largely attributable to the protection of RNA, enabling increased RNA load for downstream assays.


Assuntos
COVID-19 , Nanotubos de Carbono , Ácidos Nucleicos , Humanos , SARS-CoV-2/genética , RNA Viral/genética , COVID-19/diagnóstico
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