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1.
JAMA ; 329(24): 2135-2144, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37367978

RESUMO

Importance: Intravenous thrombolysis is increasingly used in patients with minor stroke, but its benefit in patients with minor nondisabling stroke is unknown. Objective: To investigate whether dual antiplatelet therapy (DAPT) is noninferior to intravenous thrombolysis among patients with minor nondisabling acute ischemic stroke. Design, Setting, and Participants: This multicenter, open-label, blinded end point, noninferiority randomized clinical trial included 760 patients with acute minor nondisabling stroke (National Institutes of Health Stroke Scale [NIHSS] score ≤5, with ≤1 point on the NIHSS in several key single-item scores; scale range, 0-42). The trial was conducted at 38 hospitals in China from October 2018 through April 2022. The final follow-up was on July 18, 2022. Interventions: Eligible patients were randomized within 4.5 hours of symptom onset to the DAPT group (n = 393), who received 300 mg of clopidogrel on the first day followed by 75 mg daily for 12 (±2) days, 100 mg of aspirin on the first day followed by 100 mg daily for 12 (±2) days, and guideline-based antiplatelet treatment until 90 days, or the alteplase group (n = 367), who received intravenous alteplase (0.9 mg/kg; maximum dose, 90 mg) followed by guideline-based antiplatelet treatment beginning 24 hours after receipt of alteplase. Main Outcomes and Measures: The primary end point was excellent functional outcome, defined as a modified Rankin Scale score of 0 or 1 (range, 0-6), at 90 days. The noninferiority of DAPT to alteplase was defined on the basis of a lower boundary of the 1-sided 97.5% CI of the risk difference greater than or equal to -4.5% (noninferiority margin) based on a full analysis set, which included all randomized participants with at least 1 efficacy evaluation, regardless of treatment group. The 90-day end points were assessed in a blinded manner. A safety end point was symptomatic intracerebral hemorrhage up to 90 days. Results: Among 760 eligible randomized patients (median [IQR] age, 64 [57-71] years; 223 [31.0%] women; median [IQR] NIHSS score, 2 [1-3]), 719 (94.6%) completed the trial. At 90 days, 93.8% of patients (346/369) in the DAPT group and 91.4% (320/350) in the alteplase group had an excellent functional outcome (risk difference, 2.3% [95% CI, -1.5% to 6.2%]; crude relative risk, 1.38 [95% CI, 0.81-2.32]). The unadjusted lower limit of the 1-sided 97.5% CI was -1.5%, which is larger than the -4.5% noninferiority margin (P for noninferiority <.001). Symptomatic intracerebral hemorrhage at 90 days occurred in 1 of 371 participants (0.3%) in the DAPT group and 3 of 351 (0.9%) in the alteplase group. Conclusions and Relevance: Among patients with minor nondisabling acute ischemic stroke presenting within 4.5 hours of symptom onset, DAPT was noninferior to intravenous alteplase with regard to excellent functional outcome at 90 days. Trial Registration: ClinicalTrials.gov Identifier: NCT03661411.


Assuntos
Fibrinolíticos , AVC Isquêmico , Inibidores da Agregação Plaquetária , Ativador de Plasminogênio Tecidual , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia Cerebral/induzido quimicamente , Fibrinolíticos/administração & dosagem , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , AVC Isquêmico/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/efeitos adversos , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento , Quimioterapia Combinada , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/métodos , Administração Intravenosa , Clopidogrel/administração & dosagem , Clopidogrel/efeitos adversos , Clopidogrel/uso terapêutico , Aspirina/administração & dosagem , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Seguimentos , Idoso , Recuperação de Função Fisiológica
2.
J Opt Soc Am A Opt Image Sci Vis ; 39(9): 1533-1539, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36215619

RESUMO

This work investigates how independent perturbations and cross-correlation perturbations affect optical vortex beams. Theoretical and experimental results show that both perturbations cause the intensity, average orbital angular momentum (OAM), and the OAM spectrum of the vortex beam to vary periodically with the perturbation direction, but with different periods. When the beam is subjected to independent perturbations, the average OAM changes periodically with θ in every π/2; when the beam is subjected to cross-correlation perturbations, the average OAM varies with θ in every π. The results of this work provide a method to control the OAM and regulate low-coherence vortex beams in turbulent environments.

3.
BMC Med Imaging ; 22(1): 130, 2022 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-35870877

RESUMO

BACKGROUND: Cervical cancer cell detection is an essential means of cervical cancer screening. However, for thin-prep cytology test (TCT)-based images, the detection accuracies of traditional computer-aided detection algorithms are typically low due to the overlapping of cells with blurred cytoplasmic boundaries. Some typical deep learning-based detection methods, e.g., ResNets and Inception-V3, are not always efficient for cervical images due to the differences between cervical cancer cell images and natural images. As a result, these traditional networks are difficult to directly apply to the clinical practice of cervical cancer screening. METHOD: We propose a cervical cancer cell detection network (3cDe-Net) based on an improved backbone network and multiscale feature fusion; the proposed network consists of the backbone network and a detection head. In the backbone network, a dilated convolution and a group convolution are introduced to improve the resolution and expression ability of the model. In the detection head, multiscale features are obtained based on a feature pyramid fusion network to ensure the accurate capture of small cells; then, based on the Faster region-based convolutional neural network (R-CNN), adaptive cervical cancer cell anchors are generated via unsupervised clustering. Furthermore, a new balanced L1-based loss function is defined, which reduces the unbalanced sample contribution loss. RESULT: Baselines including ResNet-50, ResNet-101, Inception-v3, ResNet-152 and the feature concatenation network are used on two different datasets (the Data-T and Herlev datasets), and the final quantitative results show the effectiveness of the proposed dilated convolution ResNet (DC-ResNet) backbone network. Furthermore, experiments conducted on both datasets show that the proposed 3cDe-Net, based on the optimal anchors, the defined new loss function, and DC-ResNet, outperforms existing methods and achieves a mean average precision (mAP) of 50.4%. By performing a horizontal comparison of the cells on an image, the category and location information of cancer cells can be obtained concurrently. CONCLUSION: The proposed 3cDe-Net can detect cancer cells and their locations on multicell pictures. The model directly processes and analyses samples at the picture level rather than at the cellular level, which is more efficient. In clinical settings, the mechanical workloads of doctors can be reduced, and their focus can be placed on higher-level review work.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Algoritmos , Detecção Precoce de Câncer/métodos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Neoplasias do Colo do Útero/diagnóstico por imagem
4.
Molecules ; 27(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36500225

RESUMO

Porphyrins have a large π-π conjugation force between molecules, and they are easy to aggregate in solution, which affects the photoelectric properties of porphyrins. Connecting porphyrins to polymer links through covalent bonds not only retains the mechanical properties and thermal stability of polymer materials, but also has the photoelectric properties and catalytic properties of porphyrins, which improves the availability of materials. In this study, first, a porphyrin ligand with double bonds in the side chain was designed and the corresponding copper and zinc complexes were synthesized by adjusting the metal ions in the center of the pyrrole ring. Then, the metalloporphyrin complexes were copolymerized with methyl methacrylate (MMA), and two metalloporphyrin/PMMA copolymers were obtained: CPTPPCu/PMMA and CPTPPZn/PMMA. The structure of the compounds was characterized by IR, 1H NMR, MS, and UV-Vis spectra. Metalloporphyrin/PMMA copolymers were prepared into electrospun fiber materials by electrospinning. The morphology of the composites was studied by SEM, and the thermal stability and optical properties of electrospun fibers were studied by TGA and FL. The catalytic activity of electrospun fiber materials for the degradation of organic dyes was studied. The results showed that the efficiency of the metalloporphyrin/PMMA copolymer in photocatalytic degradation of methylene blue (MB) was better than that of the PMMA electrospun fiber blended with metalloporphyrin.


Assuntos
Metaloporfirinas , Porfirinas , Porfirinas/química , Polimetil Metacrilato/química , Metaloporfirinas/química , Polímeros/química , Metais , Corantes
5.
Protein Expr Purif ; 182: 105841, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33582290

RESUMO

N- glycolylneuraminic acid (Neu5Gc) is a type of sialic acid, it can be synthesized by a range of mammals except chickens and healthy human. After entering human body, Neu5Gc in foods such as red meat and milk can cause chronic inflammation, thus promoting the development of cancer and related diseases. In this study, we identified a gene sequence of Neu5Gc-specific single-chain variable fragment (ScFv) by phage display from a primary chicken antibodies library. Then the gene sequence was used to express a 29 kDa anti-Neu5Gc ScFv protein as detection probe in competitive inhibition ELISA (IC-ELISA). The linear regression equation of the IC-ELISA was y = 23.12x+33.19 (R = 0.980), and the half-maximal inhibitory concentration (IC50) and the limit of detection (LOD) was 5.333 and 0.66 µg/mL. The mean recovery of the spiked samples was 83.04%, and the intra-assay and inter-assay coefficients of variation (CVs) were both 5.59%. The results suggested that the specific anti-Neu5Gc ScFv is a promising probe for the development of IC-ELISA and test strip in order to detect the presence of Neu5Gc in red meat, milk, and tumor tissues.


Assuntos
Técnicas de Visualização da Superfície Celular , Ácidos Neuramínicos/química , Biblioteca de Peptídeos , Anticorpos de Cadeia Única , Animais , Galinhas , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/genética
6.
BMC Vet Res ; 15(1): 304, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438945

RESUMO

BACKGROUND: Brucellosis is a worldwide zoonotic infectious disease that is transmitted in various ways and causes great harm to humans and animals. The brucellosis pathogen is Brucella, which mainly resides in macrophage cells and survives and replicates in host cells. However, the mechanisms underlying Brucella survival in macrophage cells have not been thoroughly elucidated to date. Peroxiredoxin 6 (Prdx6) is a bifunctional protein that shows not only GSH peroxidase activity but also phospholipase A2 activity and plays important roles in combating oxidative damage and regulating apoptosis. RESULTS: Recombinant mouse (Mus musculus) Prdx6 (MmPrdx6) was expressed and purified, and monoclonal antibodies against MmPrdx6 were prepared. Using the Brucella suis S2 strain to infect RAW264.7 murine macrophages, the level of intracellular Prdx6 expression first decreased and later increased following infection. Overexpressing Prdx6 in macrophages resulted in an increase in B. suis S2 strain levels in RAW264.7 cells, while knocking down Prdx6 reduced the S2 levels in cells. CONCLUSIONS: Host Prdx6 can increase the intracellular survival of B. suis S2 strain and plays a role in Brucella infection.


Assuntos
Brucella suis/fisiologia , Brucelose/microbiologia , Peroxirredoxina VI/metabolismo , Animais , Feminino , Regulação da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7
7.
Microb Pathog ; 116: 180-188, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29331367

RESUMO

The interleukin-1 family is an important component of the innate immune system and plays an important role in regulating immune responses on the invasion of intracellular parasites in the acquired immune system. Interleukin 1ß (IL-1ß) is one of the members of the IL-1 family that predominantly activates downstream signaling pathways to play immunological functions of stimulating T and B lymphocyte activation and promoting the various syntheses of inflammatory substances in conjunction with other cytokines. Here, a full-length IL-1ß cDNA (OaIL-1ß) of sheep (Ovis aries) was cloned using rapid amplification of cDNA ends (RACE), which consists of 1494 bp and contains a 5'-UTR region with a length of 83 bp, a complete ORF of 801 bp in length, and a 3'-UTR region with a length of 642 bp. Recombinant protein OaIL-1ß was expressed and purified, and the monoclonal antibody against IL-1ß of sheep is prepared. Western blotting results showed that the sheep IL-1ß protein was detected in the heart, liver, lung, kidney, stomach, intestine, muscle, lymph nodes and leukocytes with the highest expression in the muscle and the lowest expression in the lung. Different bacteria treating sheep white blood cells induced differential expression of OaIL-1ß. Compared with the normal sheep, OaIL-1ß in the buffy coat was differentially expressed in the Brucella melitensis-challenged group and the B. suis S2 strain-inoculated group. However, whether IL-1ß may be considered as a molecular biomarker for differing Brucella-infected animals from brucellosis-vaccinated animals or not need to be further studied.


Assuntos
Brucelose/veterinária , Perfilação da Expressão Gênica , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Doenças dos Ovinos/patologia , Carneiro Doméstico , Estruturas Animais/patologia , Animais , Brucella melitensis/imunologia , Brucella suis/imunologia , Brucelose/patologia , Clonagem Molecular , Expressão Gênica , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Ovinos
8.
Biomed Chromatogr ; 32(6): e4197, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29359465

RESUMO

rCCK8PE38 is a novel immunotoxin that targets choleystokinin B receptor, which is over-expressed in some tumor tissues. Although we constructed a prokaryotic expression vector to express rCCK8PE38 in our laboratory, thorough purification was necessary to quantitatively assess its anti-tumor effect. In this study, we established a purification protocol to obtain rCCK8PE38 with high purity from E. coli. Three different types of chromatography, hydrophobic chromatography, ion exchange chromatography and size exclusion chromatography, were used in combination. The purification technological parameters of each chromatography type were optimized. The whole process of purification was arranged to minimize the purification steps and achieve purity and bioactivity. Finally, through this optimized scheme, we obtained a recombinant protein with a purity of >95%; then, the protein was stored at -80°C after lyophilization. The purified protein was used in a tumor inhibition experiment and was effective in killing tumor cells that over-expressed choleystokinin B receptor. The results of this study may provide some valuable information about protein purification and lay the foundation for further clinical experiments with rCCK8PE38.


Assuntos
Antineoplásicos/isolamento & purificação , Imunotoxinas/isolamento & purificação , Proteínas Recombinantes/isolamento & purificação , Sulfato de Amônio/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Precipitação Química , Cromatografia Líquida , Escherichia coli/genética , Humanos , Imunotoxinas/química , Imunotoxinas/genética , Imunotoxinas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
9.
Turk J Med Sci ; 47(4): 1239-1246, 2017 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-29156869

RESUMO

Background/aim: Warfarin is a common anticoagulant with large interindividual differences and a narrow therapeutic range. The polymorphisms of gamma-glutamyl carboxylase (GGCX) are important genetic factors for warfarin dose requirements. Materials and methods: Polymerase chain reaction and direct sequencing methods were used to detect the GGCX rs699664 genotype in 215 atrial fibrillation (AF) patients with warfarin administration. The effects on warfarin dose by different genotypes were analyzed. A warfarin dosing algorithm was developed based on age, height, CYP2C9, VKORC1, and GGCX genotype. Results: In 215 AF patients, there were 104 cases of wild-type GG genotype (48.4%), 92 cases of GA genotype (42.8%), and 19 cases of AA genotype (8.8%). Patients with the GGCX rs699664 A allele (GA or AA genotypes) needed higher warfarin doses than those with the GG genotype (P < 0.05). A warfarin dosing algorithm showed that age, height, CYP2C9, VKORC1, and GGCX genotype were the best variables for estimating warfarin dose (R2 = 41.2%). Another independent cohort of 60 AF patients showed a significant linear correlation between predicted warfarin maintenance dose and actual dose (R = 0.660, P < 0.01). Conclusion: AF patients with the GA and AA genotypes in GGCX rs699664 required significantly higher warfarin doses. GGCX rs699664 is a potential predictor for the warfarin dose of AF patients.

10.
Microbiol Immunol ; 60(8): 533-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27399903

RESUMO

Poultry husbandry is a very important aspect of the agricultural economy in China. However, chicks are often susceptible to infectious disease microorganisms, such as bacteria, viruses and parasites, causing large economic losses in recent years. In the present study, we isolated an Acinetobacter baumannii strain, CCGGD201101, from diseased chicks in the Jilin Province of China. Regression analyses of virulence and LD50 tests conducted using healthy chicks confirmed that A. baumannii CCGGD201101, with an LD50 of 1.81 (±0.11) × 10(4) CFU, was more virulent than A. baumannii ATCC17978, with an LD50 of 1.73 (±0.13) × 10(7) CFU. Moreover, TEM examination showed that the pili of A. baumannii CCGGD201101 were different from those of ATCC17978. Antibiotic sensitivity analyses showed that A. baumannii CCGGD201101 was sensitive to rifampicin but resistant to most other antibiotics. These results imply that A. baumannii strain CCGGD201101 had both virulence enhancement and antibiotic resistance characteristics, which are beneficial for A. baumannii survival under adverse conditions and enhance fitness and invasiveness in the host. A. baumannii CCGGD20101, with its high virulence and antimicrobial resistance, may be one of the pathogens causing death of diseased chicks.


Assuntos
Infecções por Acinetobacter/veterinária , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Doenças das Aves Domésticas/microbiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/ultraestrutura , Animais , China , Testes de Sensibilidade Microbiana , Fenótipo , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/mortalidade , Virulência
11.
Int J Mol Sci ; 17(8)2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27483239

RESUMO

Lysophospholipase I (LYPLA1) is an important protein with multiple functions. In this study, the full-length cDNA of the LYPLA1 gene from Ovis aries (OaLypla1) was cloned using primers and rapid amplification of cDNA ends (RACE) technology. The full-length OaLypla1 was 2457 bp with a 5'-untranslated region (UTR) of 24 bp, a 3'-UTR of 1740 bp with a poly (A) tail, and an open reading frame (ORF) of 693 bp encoding a protein of 230 amino acid residues with a predicted molecular weight of 24,625.78 Da. Phylogenetic analysis showed that the OaLypla1 protein shared a high amino acid identity with LYPLA1 of Bos taurus. The recombinant OaLypla1 protein was expressed and purified, and its phospholipase activity was identified. Monoclonal antibodies (mAb) against OaLypla1 that bound native OaLypla1 were generated. Real-time PCR analysis revealed that OaLypla1 was constitutively expressed in the liver, spleen, lung, kidney, and white blood cells of sheep, with the highest level in the kidney. Additionally, the mRNA levels of OaLypla1 in the buffy coats of sheep challenged with virulent or avirulent Brucella strains were down-regulated compared to untreated sheep. The results suggest that OaLypla1 may have an important physiological role in the host response to bacteria. The function of OaLypla1 in the host response to bacterial infection requires further study in the future.


Assuntos
Brucella melitensis/genética , DNA Complementar/genética , Lisofosfolipase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Brucella melitensis/enzimologia , Brucelose/imunologia , Brucelose/veterinária , Clonagem Molecular , Feminino , Camundongos Endogâmicos BALB C , Filogenia , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase em Tempo Real , Homologia de Sequência de Aminoácidos , Ovinos
12.
Mar Drugs ; 13(12): 7433-45, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26694424

RESUMO

Okadaic acid (OA) is produced by Dinophysis and Prorocentrum dinoflagellates and primarily accumulates in bivalves, and this toxin has harmful effects on consumers and operators. In this work, we first report the use of aptamers as novel non-toxic probes capable of binding to a monoclonal antibody against OA (OA-mAb). Aptamers that mimic the OA toxin with high affinity and selectivity were generated by the magnetic bead-assisted systematic evolution of ligands by exponential enrichment (SELEX) strategy. After 12 selection rounds, cloning, sequencing and enzyme-linked immunosorbent assay (ELISA) analysis, four candidate aptamers (O24, O31, O39, O40) were selected that showed high affinity and specificity for OA-mAb. The affinity constants of O24, O31, O39 and O40 were 8.3 × 108 M(-1), 1.47 × 108 M(-1), 1.23 × 108 M(-1) and 1.05 × 108 M(-1), respectively. Indirect competitive ELISA was employed to determine the internal-image function of the aptamers. The results reveal that O31 has a similar competitive function as free OA toxin, whereas the other three aptamers did not bear the necessary internal-image function. Based on the derivation of the curvilinear equation for OA/O31, the equation that defined the relationship between the OA toxin content and O31 was Y = 2.185X - 1.78. The IC50 of O31 was 3.39 ng·mL(-1), which was close to the value predicted by the OA ELISA (IC50 = 4.4 ng·mL(-1)); the IC10 was 0.33 ng·mL(-1). The above data provides strong evidence that internal-image functional aptamers could be applicable as novel probes in a non-toxic assay.


Assuntos
Anticorpos Monoclonais/imunologia , Aptâmeros de Nucleotídeos/metabolismo , Ácido Okadáico/metabolismo , Técnica de Seleção de Aptâmeros/métodos , Aptâmeros de Nucleotídeos/imunologia , Dinoflagellida/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Concentração Inibidora 50 , Ácido Okadáico/imunologia
13.
Anal Biochem ; 459: 12-7, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24769049

RESUMO

Egg allergy is an important public health and safety concern, so quantification and administration of food or vaccines containing ovalbumin (OVA) are urgently needed. This study aimed to establish a rapid and sensitive magnetic particles-chemiluminescence enzyme immunoassay (MPs-CLEIA) for the determination of OVA. The proposed method was developed on the basis of a double antibodies sandwich immunoreaction and luminol-H2O2 chemiluminescence system. The MPs served as both the solid phase and separator, the anti-OVA MPs-coated polyclonal antibodies (pAbs) were used as capturing antibody, and the horseradish peroxidase (HRP)-labeled monoclonal antibody (mAb) was taken as detecting antibody. The parameters of the method were evaluated and optimized. The established MPs-CLEIA method had a linear range from 0.31 to 100ng/ml with a detection limit of 0.24ng/ml. The assays showed low reactivities and less than 5% of intraassay and interassay coefficients of variation (CVs), and the average recoveries were between 92 and 97%. Furthermore, the developed method was applied in real samples analysis successfully, and the correlation coefficient with the commercially available OVA kit was 0.9976. Moreover, it was more rapid and sensitive compared with the other methods for testing OVA.


Assuntos
Técnicas Imunoenzimáticas/métodos , Medições Luminescentes/métodos , Imãs/química , Ovalbumina/análise , Animais , Anticorpos Monoclonais/imunologia , Peroxidase do Rábano Silvestre/metabolismo , Vacinas contra Influenza , Masculino , Ovalbumina/imunologia , Coelhos , Fatores de Tempo
14.
Artigo em Inglês | MEDLINE | ID: mdl-24974652

RESUMO

Yersinia enterocolitica (YE) is a main pathogenic bacterium causing diarrhea and yersiniosis occurs in both developed and developing countries with high incidence. YE in contaminated food is able to survive for a long duration even under cold storage, thereby enhancing the risk of food infection. In this study, a new loop-mediated isothermal amplification (LAMP) method showing the characteristics of simplicity, rapidity, high specificity and sensitivity was established by targeting outL of pathogenic YE. Two inner-primers and outer-primers were designed and LAMP reaction was optimized for Mg2+, betaine, dNTPs and inner primers concentrations, reaction temperature and time. Sensitivity and specificity of the LAMP assay was evaluated using YE genomic DNA and those of 44 different bacteria strains, respectively. Validation of LAMP detection method was by employing meat samples spiked with varying CFU of YE. The optimized LAMP assay was specific, capable of detecting 97 fg of genomic DNA (equivalent to 37 genome copies) of YE (100-fold more sensitive than PCR) and 80 CFU/ml of YE-spiked meat samples based on ethidium bromide stained amplicon bands on agarose gel-electrophoresis and on GelRed fluorescence of the LAMP reaction solution, respectively. This rapid, sensitive and specific LAMP technique should enable application in field inspection of Y. enterocolitica in food.


Assuntos
Carne/microbiologia , Técnicas de Amplificação de Ácido Nucleico , Yersinia enterocolitica/isolamento & purificação , Animais , Bovinos , Eletroforese em Gel de Ágar , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
15.
BMC Mol Cell Biol ; 25(1): 16, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750444

RESUMO

BACKGROUND: Oxidative stress is implicated in the pathogenesis of heart failure. Dual oxidase 1 (DUOX1) might be important in heart failure development through its mediating role in oxidative stress. This study was designed to evaluate the potential role of DUOX1 in heart failure. MATERIALS AND METHODS: AC16 cells were treated with 2 µmol/L of doxorubicin (DOX) for 12, 24, and 48 h to construct a heart failure model. DUOX1 overexpression and silencing in AC16 cell were established. DUOX1 expression was detected by Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Pyroptosis and reactive oxygen species (ROS) production were measured by flow cytometry. RESULTS: Increased DUOX1 expression levels were observed after DOX treatment for 24 h in AC16 cells. DUOX1 silencing inhibited DOX-induced pyroptosis and ROS production. The release of IL-1ß, IL-18, and lactate dehydrogenase (LDH), and expression levels of pyroptosis-related proteins were also decreased. DUOX1 overexpression increased pyroptosis, ROS production, IL-1ß, IL-18, and LDH release, and pyroptosis-related protein expression. N-acetyl-cysteine (NAC) significantly reversed DUOX1-induced pyroptosis, ROS, and related factors. CONCLUSION: These results suggest that DUOX1-derived genotoxicity could promote heart failure development. In the process, oxidative stress and pyroptosis may be involved in the regulation of DUOX1 in heart failure.


Assuntos
Caspase 1 , Doxorrubicina , Oxidases Duais , Insuficiência Cardíaca , Estresse Oxidativo , Piroptose , Espécies Reativas de Oxigênio , Regulação para Cima , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/genética , Oxidases Duais/metabolismo , Oxidases Duais/genética , Espécies Reativas de Oxigênio/metabolismo , Humanos , Doxorrubicina/farmacologia , Caspase 1/metabolismo , Linhagem Celular , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo
16.
CNS Neurosci Ther ; 30(2): e14373, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37501354

RESUMO

BACKGROUND: Elderly patients often exhibit postoperative cognitive dysfunction (POCD), a postsurgical decline in memory and executive function. Oxidative stress and neuroinflammation, both pathological characteristics of the aged brain, contribute to this decline. This study posits that electroacupuncture (EA) stimulation, an effective antioxidant and anti-inflammatory modality, may enhance telomerase reverse transcriptase (TERT) function, the catalytic subunit of telomerase known for its protective properties against cellular senescence and oxidative damage, to alleviate POCD in aged mice. METHODS: The animal POCD model was created by subjecting aged mice to abdominal surgery, followed by EA pretreatment at the Baihui acupoint (GV20). Postoperative cognitive function was gauged using the Morris water maze (MWM) test. Hippocampal TERT mRNA levels and telomerase activity were determined through qPCR and a Telomerase PCR ELISA kit, respectively. Oxidative stress was assessed through superoxide dismutase (SOD), reactive oxygen species (ROS), and malondialdehyde (MDA) levels. Iba-1 immunostaining determined the quantity of hippocampal microglia. Additionally, western blotting assessed TERT, autophagy markers, and proinflammatory cytokines at the protein level. RESULTS: Abdominal surgery in aged mice significantly decreased telomerase activity and TERT mRNA and protein levels, but increased oxidative stress and neuroinflammation and decreased autophagy in the hippocampus. EA-pretreated mice demonstrated improved postoperative cognitive performance, enhanced telomerase activity, increased TERT protein expression, improved TERT mitochondrial localization, and reduced oxidative damage, autophagy dysfunction, and neuroinflammation. The neuroprotective benefits of EA pretreatment were diminished following TERT knockdown. CONCLUSIONS: Our findings underscore the significance of TERT function preservation in alleviating surgery-induced oxidative stress and neuroinflammation in aged mice. A novel neuroprotective mechanism of EA stimulation is highlighted, whereby modulation of TERT and telomerase activity reduces oxidative damage and neuroinflammation. Consequently, maintaining TERT function via EA treatment could serve as an effective strategy for managing POCD in elderly patients.


Assuntos
Disfunção Cognitiva , Eletroacupuntura , Complicações Cognitivas Pós-Operatórias , Telomerase , Animais , Camundongos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , Doenças Neuroinflamatórias , Estresse Oxidativo/fisiologia , Complicações Cognitivas Pós-Operatórias/metabolismo , RNA Mensageiro/metabolismo
17.
FEMS Microbiol Lett ; 3702023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37309037

RESUMO

Brucella is the causative agent of brucellosis and can be transmitted to humans through aerosolized particles or contaminated food. Brucella abortus (B. abortus), Brucella melitensis (B. melitensis), and Brucella suis (B. suis) are the most virulent of the brucellae, but the traditional detection methods to distinguish them are time-consuming and require high instrumentation. To obtain epidemiological information on Brucella during livestock slaughter and food contamination, we developed a rapid and sensitive triplex recombinant polymerase amplification (triplex-RPA) assay that can simultaneously detect and differentiate between B. abortus, B. melitensis, and B. suis. Three pairs of primers (B1O7F/B1O7R, B192F/B192R, and B285F/B285R) were designed and screened for the establishment of the triplex-RPA assay. After optimization, the assay can be completed within 20 min at 39°C with good specificity and no cross-reactivity with five common pathogens. The triplex-RPA assay has a DNA sensitivity of 1-10 pg and a minimum detection limit of 2.14 × 104-2.14 × 105 CFU g-1 in B. suis spiked samples. It is a potential tool for the detection of Brucella and can effectively differentiate between B. abortus, B. melitensis, and B. suis S2, making it a useful tool for epidemiological investigations.


Assuntos
Brucella melitensis , Brucella suis , Brucelose , Humanos , Brucella abortus/genética , Brucella suis/genética , Brucella melitensis/genética , Recombinases , Brucelose/diagnóstico , Brucelose/veterinária , Nucleotidiltransferases
18.
Artigo em Inglês | MEDLINE | ID: mdl-38041745

RESUMO

Brucellosis is a zoonosis caused by Brucella, which poses a great threat to human health and animal husbandry. Pathogen surveillance is an important measure to prevent brucellosis, but the traditional method is time-consuming and not suitable for field applications. In this study, a recombinase polymerase amplification-SYBR Green I (RPAS) assay was developed for the rapid and visualized detection of Brucella in the field by targeting BCSP31 gene, a conserved marker. The method was highly specific without any cross-reactivity with other common bacteria and its detection limit was 2.14 × 104 CFU/mL or g of Brucella at 40 °C for 20 min. It obviates the need for costly instrumentation and exhibits robustness towards background interference in serum, meat, and milk samples. In summary, the RPAS assay is a rapid, visually intuitive, and user-friendly detection that is highly suitable for use in resource-limited settings. Its simplicity and ease of use enable swift on-site detection of Brucella, thereby facilitating timely implementation of preventive measures.

19.
Anal Biochem ; 422(2): 59-65, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22266294

RESUMO

A lateral flow immunochromatographic (LFIC) test strip based on a colloidal gold-monoclonal antibody (McAb) conjugate was developed for on-site rapid detection of okadaic acid (OA) in shellfish. It applies a competitive format using an immobilized toxin conjugate and free toxin present in samples. The McAb against OA was conjugated with 20-nm colloidal gold as detector reagent. The toxin in the sample competed with the immobilized toxin to bind to the gold conjugated with McAb. The colloidal gold/McAb/toxin mobile complex was not captured by OA-bovine serum albumin (BSA) on the test line, but it was captured by goat anti-mouse immunoglobulin G (IgG) on the control line. The color density of the test line correlated with the concentration of toxin in the range of 10-50 ng ml(-1). The qualitative detection limit of 150 µg kg(-1) sample was close to the European Union (EU) regulatory limit (160 µg kg(-1)). Therefore, these strips were able to directly and qualitatively estimate the consuming safety of shellfish. They require no equipment because of available visual results, and they screened numerous samples within 10 min. The results were further confirmed by high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). As a food safety screening tool, the test strips are convenient and useful to rapidly on-site test the presence of OA in shellfish products.


Assuntos
Carcinógenos/análise , Cromatografia de Afinidade/métodos , Contaminação de Alimentos/análise , Ácido Okadáico/análise , Venenos/análise , Frutos do Mar/análise , Animais , Anticorpos Monoclonais , Bovinos , Cromatografia de Afinidade/economia , Cromatografia Líquida de Alta Pressão , Cabras , Coloide de Ouro , Limite de Detecção , Camundongos , Soroalbumina Bovina , Espectrometria de Massas em Tandem
20.
Nanomaterials (Basel) ; 12(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36234642

RESUMO

In this study, we investigated an absorber based on a center-aligned tandem nanopillar array for ultra-broadband solar energy harvesting theoretically. A high-efficiency, omnidirectional absorber was obtained by introducing the center-aligned tandem nanopillar array embedded in an Al2O3 dielectric layer. The multi-coupling modes at different wavelengths were interpreted. The strong absorption can be adjusted by changing the radii and heights of nanopillars. According to the simulation results, the average absorptance of the absorber exceeded 94% in the wavelength range from 300 nm to 2000 nm. In addition, the high-efficiency absorption was insensitive to the incident angle and polarization state. The research not only proposed an absorber which possesses a huge potential value for application areas, such as thermal photovoltaic systems, infrared detection, and isotropic absorption sensors, but also pointed out a new way to design an absorber with high efficiency in an ultrabroad wavelength range.

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