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1.
Small ; : e2310026, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860348

RESUMO

Since the proposal of the concept of spherical nucleic acids (SNAs) in 1996, numerous studies have focused on this topic and have achieved great advances. As a new delivery system for nucleic acids, SNAs have advantages over conventional deoxyribonucleic acid (DNA) nanostructures, including independence from transfection reagents, tolerance to nucleases, and lower immune reactions. The flexible structure of SNAs proves that various inorganic or organic materials can be used as the core, and different types of nucleic acids can be conjugated to realize diverse functions and achieve surprising and exciting outcomes. The special DNA nanostructures have been employed for immunomodulation, gene regulation, drug delivery, biosensing, and bioimaging. Despite the lack of rational design strategies, potential cytotoxicity, and structural defects of this technology, various successful examples demonstrate the bright and convincing future of SNAs in fields such as new materials, clinical practice, and pharmacy.

2.
Int Arch Allergy Immunol ; : 1-10, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38583424

RESUMO

INTRODUCTION: No previous studies have evaluated the levels of neutrophil extracellular trap (NET) remnants or the importance of deoxyribonuclease (DNase) I activity based on the disease activity of otitis media with antineutrophil cytoplasmic antibody-associated vasculitis (OMAAV). The aim of this study was to explore the formation of NETs in the middle ear of patients with OMAAV during the onset and remission phases of the disease, with a particular focus on the relationships between the quantifiable levels of NET remnants and DNase I activity. METHODS: OMAAV patients were eligible for inclusion. Patients with otitis media with effusion (OME) were examined as controls. The levels of cell-free deoxyribonucleic acid (DNA), citrullinated-histone H3 (cit-H3)-DNA complex, and myeloperoxidase (MPO)-DNA complex were quantified using an enzyme-linked immunosorbent assay. DNase I activity was measured using a fluorometric method. RESULTS: The quantifiable levels of cell-free DNA, cit-H3-DNA complex, and MPO-DNA complex in the middle ear lavage of patients with OMAAV at onset were significantly higher than those in patients with OMAAV at remission and in patients with OME. DNase I activity in the patients with OMAAV at onset was significantly lower than those in patients with OMAAV at remission and OME and was negatively correlated with the level of MPO-DNA complex. CONCLUSIONS: This study suggests that NET remnants and DNase I activity may be potentially useful biomarkers for the diagnosis and disease activity of OMAAV.

3.
Prev Med ; 184: 107981, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38701951

RESUMO

OBJECTIVE: Although colorectal cancer screening (CRCS) is a public health priority, uptake is suboptimal in under-resourced groups. Noninvasive modalities, including stool deoxyribonucleic acid (sDNA) testing, may mitigate economic, geographic, cultural, or impairment-related barriers to CRCS. We assessed use of sDNA testing and other CRCS modalities in U.S. residents, comparing subgroups defined by several social determinants of health (SDOH). METHODS: A nationally representative sample of community-dwelling respondents aged 50-75 years self-reported use of CRCS modalities in the 2020 Behavioral Risk Factor Surveillance System Survey. Statistical analyses assessed up-to-date screening status and choice of modality in the recommended screening interval. RESULTS: Of 179,833 sampled respondents, 60.8% reported colonoscopy, 5.7% sDNA testing, 5.5% another modality. The rate of up-to-date screening was 72.0% overall and negatively associated with Hispanic ethnicity (63.6%), lower educational and annual income levels (e.g.,

Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Fezes , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Estados Unidos , Fezes/química , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/estatística & dados numéricos , Sistema de Vigilância de Fator de Risco Comportamental , DNA/análise , Colonoscopia/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricos , Determinantes Sociais da Saúde
4.
Luminescence ; 39(3): e4716, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38497410

RESUMO

A fluorescence resonance energy transfer (FRET) method was developed for double-stranded deoxyribonucleic acid (dsDNA) detection in living cells using the RecA-GFP (green fluorescent protein) fusion protein filament. In brief, the thiol-modified single-stranded DNA (ssDNA) was attached to gold nanoparticles (AuNPs); on the contrary, the prepared RecA-GFP fusion protein interacted with ssDNA. Due to the FRET between AuNPs and RecA-GFP, fluorescence of RecA-GFP fusion protein was quenched. In the presence of homologous dsDNA, homologous recombination occurred to release RecA-GFP fusion protein. Thus, the fluorescence of RecA-GFP was recovered. The dsDNA concentration was detected using fluorescence intensity of RecA-GFP. Under optimal conditions, this method could detect dsDNA activity as low as 0.015 optical density (OD) Escherichia coli cells, with a wide linear range from 0.05 to 0.9 OD cells, and the regression equation was ΔF = 342.7c + 78.9, with a linear relationship coefficient of 0.9920. Therefore, it provided a promising approach for the selective detection of dsDNA in living cells for early clinical diagnosis of genetic diseases.


Assuntos
DNA de Cadeia Simples , Nanopartículas Metálicas , Transferência Ressonante de Energia de Fluorescência , Proteínas de Fluorescência Verde/genética , Ouro/metabolismo , DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo
5.
Am J Transplant ; 23(6): 727-735, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36870390

RESUMO

In heart transplantation, the use of biomarkers to detect the risk of rejection has been evolving. In this setting, it is becoming less clear as to what is the most reliable test or combination of tests to detect rejection and assess the state of the alloimmune response. Therefore, a virtual expert panel was organized in heart and kidney transplantation to evaluate emerging diagnostics and how they may be best utilized to monitor and manage transplant patients. This manuscript covers the heart content of the conference and is a work product of the American Society of Transplantation's Thoracic and Critical Care Community of Practice. This paper reviews currently available and emerging diagnostic assays and defines the unmet needs for biomarkers in heart transplantation. Highlights of the in-depth discussions among conference participants that led to development of consensus statements are included. This conference should serve as a platform to further build consensus within the heart transplant community regarding the optimal framework to implement biomarkers into management protocols and to improve biomarker development, validation and clinical utility. Ultimately, these biomarkers and novel diagnostics should improve outcomes and optimize quality of life for our transplant patients.


Assuntos
Transplante de Coração , Transplante de Rim , Humanos , Qualidade de Vida , Transplante de Coração/efeitos adversos , Biomarcadores , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia
6.
Small ; 19(37): e2301996, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37116115

RESUMO

The effective regeneration of weight-bearing bone defects and critical-sized cartilage defects remains a significant clinical challenge. Traditional treatments such as autologous and allograft bone grafting have not been successful in achieving the desired outcomes, necessitating the need for innovative therapeutic approaches. Nucleic acids have attracted significant attention due to their ability to be designed to form discrete structures and programmed to perform specific functions at the nanoscale. The advantages of nucleic acid nanotechnology offer numerous opportunities for in-cell and in vivo applications, and hold great promise for advancing the field of biomaterials. In this review, the current abilities of nucleic acid nanotechnology to be applied in bone and cartilage regeneration are summarized and insights into the challenges and future directions for the development of this technology are provided.


Assuntos
Ácidos Nucleicos , Nanotecnologia , Cartilagem , Regeneração Óssea , Materiais Biocompatíveis
7.
BMC Cancer ; 23(1): 410, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149594

RESUMO

BACKGROUND: To develop and validate a predictive nomogram for tumor residue 3-6 months after treatment based on postradiotherapy plasma Epstein-Barr virus (EBV) deoxyribonucleic acid (DNA), clinical stage, and radiotherapy (RT) dose in patients with stage II-IVA nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). METHODS: In this retrospective study, 1050 eligible patients with stage II-IVA NPC, who completed curative IMRT and underwent pretreatment and postradiotherapy (-7 to +28 days after IMRT) EBV DNA testing, were enrolled from 2012 to 2017. The prognostic value of the residue was explored using Cox regression analysis in patients (n=1050). A nomogram for predicting tumor residues after 3-6 months was developed using logistic regression analyses in the development cohort (n=736) and validated in an internal cohort (n=314). RESULTS: Tumor residue was an independent inferior prognostic factor for 5-year overall survival, progression-free survival, locoregional recurrence-free survival and distant metastasis-free survival (all P<0.001). A prediction nomogram based on postradiotherapy plasma EBV DNA level (0 vs. 1-499 vs. ≥500 copies/ml), clinical stage (II vs. III vs. IVA), and RT dose (68.00-69.96 vs. 70.00-74.00 Gy) estimated the probability of residue development. The nomogram showed better discrimination (area under the curve (AUC): 0.752) than either the clinical stage (0.659) or postradiotherapy EBV DNA level (0.627) alone in the development and validation cohorts (AUC: 0.728). CONCLUSIONS: We developed and validated a nomogram model integrating clinical characteristics at the end of IMRT for predicting whether tumor will residue or not after 3-6 months. Thus, high-risk NPC patients who might benefit from immediate additional intervention could be identified by the model, and the probability of residue can be reduced in the future.


Assuntos
Carcinoma , Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Humanos , Carcinoma Nasofaríngeo/patologia , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/radioterapia , Carcinoma/patologia , Estudos Retrospectivos , Nomogramas , Neoplasias Nasofaríngeas/patologia , DNA Viral , Prognóstico
8.
Cancer Control ; 30: 10732748231170483, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37057688

RESUMO

Currently, genetic tests that predict cancer risk or risk of recurrence in patients who have had their cancer treated with curative intent must have proven "clinical utility" to be recommended by the organizations responsible for publishing the standard-of-care guidelines for cancer care.Based on the current definition of clinical utility, most patients are denied testing for cancer-predisposing genes or pathogenic germline variants even though germline testing has been proven as highly accurate in identifying pathogenic germline variant carriers, there are measures recommended to prevent and diagnose early cancers associated with particular PGVs, and disparities in patient access to genetic tests are well described.Similarly, despite dozens of studies demonstrating that detected circulating tumor DNA (ctDNA) after curative intention therapy of different cancer types is a highly accurate biomarker that predicts recurrence, the major organizations that publish guidelines for cancer monitoring after curative intention therapy recommend against using ctDNA assays to detect minimal residual disease and thereby predict recurrence for all solid tumor malignancies.Here, the primary reasons that these genetic tests are considered to lack proven clinical utility and the primary evidence suggesting that a broader definition of clinical utility should be considered are discussed. By expanding the definition of clinical utility, many patients will benefit from the information gained from having these genetic tests.


Assuntos
Detecção Precoce de Câncer , Predisposição Genética para Doença , Testes Genéticos , Recidiva Local de Neoplasia , Neoplasias , Acesso dos Pacientes aos Registros , Mutação em Linhagem Germinativa , Humanos , Neoplasias/diagnóstico , Neoplasias/genética , Detecção Precoce de Câncer/normas , Testes Genéticos/normas , Risco , DNA Tumoral Circulante/sangue , Prática Clínica Baseada em Evidências/normas , Padrão de Cuidado , Neoplasia Residual/sangue , Neoplasia Residual/diagnóstico , Guias de Prática Clínica como Assunto , Medicina de Precisão/normas , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Satisfação do Paciente
9.
J Sep Sci ; 46(16): e2300160, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37269050

RESUMO

Siegesbeckiae Herba, a traditional Chinese medicine, originates from Siegesbeckia orientalis, S. glabrescens, and S. pubescens in the Pharmacopoeia of the People's Republic of China. However, accurate identification of decoction pieces from the three plants remains a challenge. In this study, 26 batches of Siegesbeckiae Herba were identified by deoxyribonucleic acid barcoding, and their chemical compositions were determined using ultra-performance liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry. The results showed that the internal transcribed spacer 2 and internal transcribed spacer 1-5.8 S- internal transcribed spacer 2 sequences could distinguish three species. In total, 48 compounds were identified including 12 marker compounds screened for three species using the partial least square discriminant analysis. Among these, two diterpenoids 16-O-malonylkirenol and 15-O-malonylkirenol, and a novel diterpenoid 15,16-di-O-malonylkirenol were isolated and identified. A convenient method for the identification of Siegesbeckiae Herba was established using kirenol and 16-O-acetlydarutoside as control standards by thin-layer chromatography. Unexpectedly, none of the batches of S. orientalis contained kirenol, which did not meet the quality standards of Siegesbeckiae Herba, suggesting that the rationality of kirenol as a quality marker for S. orientalis should be further investigated. The results of this study will contribute to the quality control of Siegesbeckiae Herba.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas por Ionização por Electrospray , Humanos , Espectrometria de Massas por Ionização por Electrospray/métodos , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida/métodos , DNA , Cromatografia Líquida de Alta Pressão/métodos
10.
Electrophoresis ; 43(16-17): 1746-1754, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35656648

RESUMO

The laser print, cut, and laminate (PCL) method for microfluidic device fabrication can be leveraged for rapid and inexpensive prototyping of electrophoretic microchips useful for optimizing separation conditions. The rapid prototyping capability allows the evaluation of fluidic architecture, applied fields, reagent concentrations, and sieving matrix, all within the context of using fluorescence-compatible substrates. Cyclic olefin copolymer and toner-coated polyethylene terephthalate (tPeT) were utilized with the PCL technique and bonding methods optimized to improve device durability during electrophoresis. A series of separation channel designs and centrifugation conditions that provided successful loading of sieving polymer in less than 3 min was described. Separation of a 400-base DNA sizing ladder provided calculated base resolution between 3 and 4 bases, a greater than 18-fold improvement over separations on similar substrates. Finally, the accuracy and precision capabilities of these devices were demonstrated by separating and sizing DNA fragments of 147 and 167 bases as 148.62 ± 2 and 166.48 ± 3 bases, respectively.


Assuntos
DNA , Dispositivos Lab-On-A-Chip , Centrifugação , DNA/análise , Eletroforese , Polímeros
11.
BMC Cancer ; 22(1): 1035, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36192767

RESUMO

BACKGROUND: This study aimed to determine the effectiveness of liquid biopsy in detecting epidermal growth factor receptor (EGFR) mutations at diagnosis, disease progression, and intermediate stages. METHODS: This prospective, multicenter, observational study included 30 patients with non-small cell lung cancer treated with afatinib, harboring a major EGFR mutation confirmed by tumor tissue biopsy. We collected blood samples for liquid biopsy at diagnosis, intermediate stage, and progressive disease. Tissue and liquid biopsies were examined using Cobas ® EGFR Mutation Test v2. RESULTS: Liquid biopsy detected EGFR mutations in 63.6% of the patients at diagnosis. The presence of metastasis in the extrathoracic, brain, and adrenal glands correlated positively with the detection of EGFR mutations. Patients with positive EGFR mutations at diagnosis had significantly shorter overall and progression-free survival than patients with negative EGFR mutations. Four of the 18 patients (22.2%) who reached progressive disease had positive EGFR T790M mutations. Three of 10 patients (30.0%) with progressive disease were positive and negative for T790M using tumor re-biopsy and liquid biopsy, respectively. The results of EGFR mutation by tissue re-biopsy were the same as those of liquid biopsy in the three patients who were positive for significant EGFR mutations but negative for the T790M mutation using liquid biopsy at progressing disease. Only two patients were positive for major EGFR mutations at intermediate levels. CONCLUSIONS: Liquid biopsy can be a prognostic factor in EGFR-tyrosine kinase inhibitor treatments at diagnosis. Tumor re-biopsy can be omitted in patients with positive EGFR mutations by liquid biopsy at PD.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Afatinib/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Humanos , Biópsia Líquida/métodos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico
12.
Anal Biochem ; 657: 114905, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36154836

RESUMO

In the present study, the objective was to evaluate in situ interaction between Benzo[a]anthracene 7,2-dione 7-oxime (BZA) and calf thymus dsDNA (ct-dsDNA) using electroanalytical genosensor. Analytical techniques based on Ultraviolet/Visible (UV-Vis) spectroscopy and electroanalytical were used to investigate the interaction processes in solution and immobilized on carbon screen-printed electrodes modified with electrochemical mediator Meldola blue. In addition, was possible to evaluate the degree of damage caused to the genetic material by the analyte through of toxicity estimate (S%). The interaction evaluated by genosensor showed processes of intercalation, degradation, and breaks of the double strand of ct-dsDNA, suggesting that the interaction simulates highly toxic (values varying from 0.6 to 0.8 µA in 48 h of interaction), such as 8-oxoguanine (+0.48 V), which is a by-product of guanine oxidation. Furthermore, monitoring A (+1.10 V) after 1 h showed an S% value between 50 and 90%, indicative of high toxicity, and monitoring G (+0.85 V), which showed S>90%, indicated no toxicity after 10 min. Overall, the electroanalytical genosensor developed in a miniaturized system displayed good reproducibility and stability over time being a quick alternative for assesses the degree of toxicity between toxic xenobiotics and biologically electroactive molecules, such as DNA.


Assuntos
Técnicas Biossensoriais , Oximas , Antracenos , Técnicas Biossensoriais/métodos , Carbono/química , DNA/química , Eletrodos , Guanina , Reprodutibilidade dos Testes
13.
Cancer Control ; 29: 10732748221114980, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35829643

RESUMO

OBJECTIVES: The aim of this study was to evaluate the performance of visual inspection with acetic acid compared with Human papillomavirus Deoxyribonucleic acid (HPV DNA) testing among women with HIV in Ethiopia. METHODS: A comparative cross-sectional study was conducted to address the aforementioned objective. Data were collected from January to October 2021, to compare the performance of these two screening modalities. Trained clinicians collected cervical specimens and immediately applied acetic acid for visual inspection. The HPV DNA testing was done using Abbott m2000rt/SP by trained laboratory professionals in accredited laboratories. A total of 578 women with HIV aged 25-49 years were included. RESULTS: Test positivity was 8.9% using visual inspection with acetic acid (VIA) and 23.3% using HPV DNA test. The sensitivity and specificity of the VIA test were 19.2% and 95.1%, respectively. The strength of agreement between the two screening methods was poor (k = .184). The burden of genetic distribution of high risk HPV16 was 6.1%, and HPV18 was 1.1%. Other high risk HPV types (ie non-HPV 16/18 high risk HPV genotypes) were predominant in this study (18.6%). CONCLUSION: The higher positivity result using HPV DNA testing compared with VIA, and low sensitivity of VIA are indicating that the implementation of HPV DNA testing as the primary screening strategy is likely to reduce cervical cancer cases and deaths of women in the country.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Ácido Acético , Estudos Transversais , DNA Viral/genética , Detecção Precoce de Câncer/métodos , Etiópia/epidemiologia , Feminino , Infecções por HIV/diagnóstico , Papillomavirus Humano 16 , Humanos , Programas de Rastreamento/métodos , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico
14.
Environ Sci Technol ; 56(1): 218-227, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34905340

RESUMO

Free chlorine disinfection is widely applied to inactivate viruses by reacting with their biomolecules, which include nucleic acids, proteins, and lipids. Knowing the reactivities of viral genomes with free chlorine and the protection that encapsidation provides would ultimately help predict virus susceptibility to the disinfectant. The relative reactivities of different viral genome types and the impact of viral higher order structure with free chlorine are poorly characterized. Here, we studied the reactivity of viral genomes representing four genome types from virus particles with diverse structures, namely, (+)ssRNA (MS2), dsRNA (φ6), ssDNA (φX174), and dsDNA (T3) with free chlorine. We compared the reactivities of these viral nucleic acids when they were suspended in phosphate buffer solutions (naked forms) and when they were in the native virus particles (encapsidated forms). The reactivities of nucleic acids were tracked by polymerase chain reaction (PCR)-based assays. The naked dsDNA of T3 was the least reactive with free chlorine, with an average second order rate constant normalized by the number of bases in the measured regions (in M-1 s-1 b-1) that was 34×, 65×, and 189× lower than those of the dsRNA of φ6, ssRNA of MS2, and ssDNA of φX174, respectively. Moreover, different regions in the ssRNA genome of MS2 and the dsRNA genome of φ6 exhibited statistically different reaction kinetics. The genomes within virus particles reacted slower than the naked genomes overall, but the extent of these differences varied among the four viruses. The results on viral nucleic acid reactivity help explain different susceptibilities of viruses to inactivation by free chlorine and also provide a valuable comparison of the susceptibilities of different nucleic acids to oxidants.


Assuntos
Ácidos Nucleicos , Vírus , Cloro/farmacologia , Desinfecção/métodos , Inativação de Vírus
15.
Environ Sci Technol ; 56(18): 13347-13356, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36027047

RESUMO

Free available chlorine (FAC) is widely used to inactivate viruses by oxidizing viral components, including genomes. It is commonly assumed that hypochlorous acid (HOCl) is the chlorinating agent responsible for virus inactivation; however, recent studies have underscored that minor constituents of FAC existing in equilibrium with HOCl, such as molecular chlorine (Cl2), can influence FAC reactivity toward select organic compounds. This study measures the FAC reaction kinetics with dsDNA and ssDNA extracted from representative bacteriophages (T3 and ϕX174) in samples augmented with chloride. Herein, chloride enhances FAC reactivity toward dsDNA and, to a lesser extent, toward ssDNA, especially at pH < 7.5. The enhanced reactivity can be attributed to the formation of Cl2. Second-order rate constants were determined for reactions of ssDNA and dsDNA with HOCl and Cl2. DNA chlorination kinetics followed the reactivity-selectivity principle, where the more-reactive nucleophilic species (ssDNA, ∼100× more reactive than dsDNA) reacted less selectively with electrophilic FAC species. The addition of chloride was also shown to enhance the inactivation of bacteriophage T3 (dsDNA genome) by FAC but did not enhance the inactivation of bacteriophage ϕX174 (ssDNA genome). Overall, the results suggest that Cl2 is an important chlorinating agent of nucleic acids and viruses.


Assuntos
Ácidos Nucleicos , Purificação da Água , Cloretos , Cloro/química , DNA , Concentração de Íons de Hidrogênio , Ácido Hipocloroso/química , Cinética , Purificação da Água/métodos
16.
J Fluoresc ; 32(2): 443-448, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35064858

RESUMO

Low-cost analytical solutions built around microcomputers like the Raspberry Pi help to facilitate laboratory investigations in resource limited venues. Here, three camera modules (V1.3 with and without filter, as well as NoIR) that work with this microcomputer were assessed for their suitability in imaging fluorescent DNA following agarose gel electrophoresis. Evaluation of their utility was based on signal-to-noise (SNR) and noise variance metrics that were developed. Experiments conducted with samples were subjected to Polymerase Chain Reaction (PCR), and the amplified products were separated using gel electrophoresis and stained with Midori green. Image analysis revealed the NoIR camera performed the best with SNR and noise variance values of 21.7 and 0.222 respectively. In experiments conducted using UV LED lighting to simulate ethidium bromide (EtBr) excitation, the NoIR and V1.3 with filter removed cameras showed comparable SNR values.


Assuntos
DNA/análise , Eletroforese em Gel de Ágar/métodos , Corantes Fluorescentes , Microcomputadores , Reação em Cadeia da Polimerase , Coloração e Rotulagem
17.
Electrochim Acta ; 429: 140988, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36225971

RESUMO

The absence of reliable species-specific diagnostic tools for malaria at point-of-care (POC) remains a major setback towards effective disease management. This is partly due to the limited sensitivity and specificity of the current malaria POC diagnostic kits especially in cases of low-density parasitaemia and mixed species infections. In this study, we describe the first label-free DNA-based genosensors based on electrochemical impedance spectroscopy (EIS) for species-specific detection of P. falciparum, P. malariae and P. ovale. The limits of detection (LOD) for the three species-specific genosensors were down in attomolar concentrations ranging from 18.7 aM to 43.6 aM, which is below the detection limits of previously reported malaria genosensors. More importantly, the diagnostic performance of the three genosensors were compared to quantitative real-time polymerase chain reaction (qPCR) assays using purified genomic DNA and the paired whole blood lysates from clinical samples. Remarkably, all the qPCR-positive purified genomic DNA samples were correctly identified by the genosensors indicating 100% sensitivity for each of the three malaria species. The specificities of the three genosensors ranged from 66.7% to 100.0% with a Therapeutic Turnaround Time (TTAT) within 30 min, which is comparable to the TTAT of current POC diagnostic tools for malaria. This work represents a significant step towards the development of accurate and rapid species-specific nucleic acid-based toolkits for the diagnosis of malaria at the POC.

18.
IEEE Sens J ; 22(19): 18437-18445, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36416744

RESUMO

The development of a cost-efficient device to rapidly detect pandemic viruses is paramount. Hence, an innovative and scalable synthesis of metal nanoparticles followed by its usage for rapid detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been reported in this work. The simple synthesis of metal nanoparticles utilizing tin as a solid-state reusable reducing agent is used for the SARS-CoV-2 ribonucleic acid (RNA) detection. Moreover, the solid-state reduction process occurs faster and leads to the enhanced formation of silver and gold nanoparticles (AuNPs) with voltage. By adding tin as a solid-state reducing agent with the precursor, the nanoparticles are formed within 30 s. This synthesis method can be easily scaled up for a commercially viable process to obtain different-sized metal nanoparticles. This is the first disclosure of the usage of tin as a reusable solid-state reducing agent for metal nanoparticle synthesis. An electronic device, consisting of AuNPs functionalized with a deoxyribonucleic acid (DNA)-based aptamer, can detect SARS-CoV-2 RNA in less than 5 min. With an increase in SARS-CoV-2 variants, such as Delta and Omicron, the detection device could be used for identifying the nucleic acids of the COVID-19 variants by modifying the aptamer sequence. The reported work overcomes the drawbacks of complex instrumentation, trained labor, and increased turnaround time.

19.
Radiat Phys Chem Oxf Engl 1993 ; 198: 110265, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35663798

RESUMO

The world is still suffering from the SARS-CoV-2 pandemic, and the number of infected people is still growing in many countries in 2022. Although great strides have been made to produce effective vaccines, efforts in this field should be accelerated, particularly due to the emergence of new variants. Using inactivated viruses is a conventional method of vaccine production. High levels of ionizing radiation can effectively inactivate viruses. Recently, studies on SARS-CoV-2 irradiation using low-LET radiations (e.g., gamma rays) have been performed. However, there are insufficient studies on the impact of charged particles on the inactivation of this virus. In this study, a realistic structure of SARS-CoV-2 is simulated by using Geant4 Monte Carlo toolkit, and the effect of electrons, protons, alphas, C-12, and Fe-56 ions on the inactivation of SARS-CoV-2 is investigated. The simulation results indicated that densely ionizing (high-LET) particles have the advantage of minimum number of damaged spike proteins per single RNA break. The RNA breaks induced by hydroxyl radicals produced in the surrounding water medium were significant only for electron beam radiation. Hence, indirect RNA breaks induced by densely ionizing particles is negligible. From a simulation standpoint, alpha particles (with energies up to 30 MeV) as well as C-12 ions (with energies up to 80 MeV/n), and Fe-56 ions (with any energy) can be introduced as particles of choice for effective SARS-CoV-2 inactivation.

20.
J Obstet Gynaecol ; 42(6): 2373-2380, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35611871

RESUMO

This study aimed to investigate the association between deoxyribonucleic acid (DNA) integrity parameters and advanced maternal age (AMA)-related infertility. The granulosa cells and the lymphocytes obtained from 119 infertile women were recruited. Patients were divided into two groups: the AMA group (≥35 years, n = 26) and the non-AMA group (<35 years, n = 93). The tail length, tail moment and tail DNA percentage were evaluated as the DNA integrity parameters using comet assay. Infertility duration (p=.001), luteinising hormone (p=.01) and progesterone levels (p<.0001) were higher and smoking was more prevalent in the AMA group (p=.001). AMA group was stimulated with higher gonadotropin doses (p=.04) and had decreased anti-mullerian hormone levels (p<.0001). All of DNA integrity parameters were distributed homogenously between the groups; however, the tail length of lymphocytes was higher (p=.02) in the AMA group. Fertilisation was lower (p=.02), oocyte quality was tended to be poor (p=.03) and blastocyst transfer was lower in the AMA group (p=.03). Embryo quality was distributed homogenously between the groups. Implantation, clinical pregnancy and live birth rates were similar between the groups. Impact StatementWhat is already known on this subject? Advanced maternal age (AMA)-related infertility is associated with diminished ovarian reserve and alteration in follicular environment resulting in poor oocyte quality; however, the exact pathophysiologic mechanism is not clear.What do the results of this study add? Tail length, tail deoxyribonucleic acid (DNA) percentage, tail moment of granulosa cells were nonsignificantly higher in the AMA group compared to younger patients. All of the DNA integrity parameters of lymphocytes were nonsignificantly higher; however, only tail length of lymphocytes was statistically higher in the AMA group than the non-AMA group. A positive correlation was observed between DNA integrity parameters of lymphocytes and body mass index. There were no correlations between DNA integrity parameters of granulosa cells and lymphocyte and infertility duration, gonadotropin dose, duration of ovarian stimulation, oocyte score, embryo score, basal hormone levels and anti-mullerian hormone levels.What are the implications of these findings for clinical practice and/or further research? Our findings offer new insight for further understanding the role of granulosa cells in mediating the poor reproductive outcome of ageing patients. Understanding the mechanisms of ovarian ageing and poor oocyte quality in women with AMA may help to identify specific targets for improving oocyte quality with ageing.


Assuntos
Hormônio Antimülleriano , Infertilidade Feminina , DNA , Feminino , Fertilização in vitro/métodos , Gonadotropinas , Células da Granulosa , Humanos , Hormônio Luteinizante , Linfócitos , Indução da Ovulação , Gravidez , Taxa de Gravidez , Progesterona
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