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1.
Adv Sci (Weinh) ; 11(19): e2400966, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38483027

RESUMO

Ionic memristors can emulate brain-like functions of biological synapses for neuromorphic technologies. Apart from the widely studied excitatory-excitatory and excitatory-inhibitory synapses, reports on memristors with the inhibitory-inhibitory synaptic behaviors remain a challenge. Here, the first biaxially inhibited artificial synapse is demonstrated, consisting of a solid electrolyte and conjugated microporous polymers bilayer as neurotransmitter, with the former serving as an ion reservoir and the latter acting as a confined transport. Due to the migration, trapping, and de-trapping of ions within the nanoslits, the device poses inhibitory synaptic plasticity under both positive and negative stimuli. Remarkably, the artificial synapse is able to maintain a low level of stable nonvolatile memory over a long period of time (≈60 min) after multiple stimuli, with feature-inferencing/-training capabilities of neural node in neuromorphic computing. This work paves a reliable strategy for constructing nanochannel ionic memristive materials toward fully inhibitory synaptic devices.


Assuntos
Eletrólitos , Neurotransmissores , Sinapses , Sinapses/fisiologia , Eletrólitos/química , Porosidade , Plasticidade Neuronal/fisiologia
2.
Adv Mater ; : e2311472, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421081

RESUMO

Human-machine interaction (HMI) technology has undergone significant advancements in recent years, enabling seamless communication between humans and machines. Its expansion has extended into various emerging domains, including human healthcare, machine perception, and biointerfaces, thereby magnifying the demand for advanced intelligent technologies. Neuromorphic computing, a paradigm rooted in nanoionic devices that emulate the operations and architecture of the human brain, has emerged as a powerful tool for highly efficient information processing. This paper delivers a comprehensive review of recent developments in nanoionic device-based neuromorphic computing technologies and their pivotal role in shaping the next-generation of HMI. Through a detailed examination of fundamental mechanisms and behaviors, the paper explores the ability of nanoionic memristors and ion-gated transistors to emulate the intricate functions of neurons and synapses. Crucial performance metrics, such as reliability, energy efficiency, flexibility, and biocompatibility, are rigorously evaluated. Potential applications, challenges, and opportunities of using the neuromorphic computing technologies in emerging HMI technologies, are discussed and outlooked, shedding light on the fusion of humans with machines.

3.
J Geriatr Cardiol ; 20(4): 284-292, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37122987

RESUMO

BACKGROUND: Epidemiological surveys on heart failure (HF) in Chinese community are relatively lacking. This study aimed to estimate the prevalence and incidence of HF among community residents in southern China. METHODS: Baseline data of this prospective study was collected from 2015 to 2017 among 12,013 permanent residents aged ≥ 35 years in Guangzhou, China. The same survey process was carried out for individuals aged ≥ 65 years after a three-year follow-up. RESULTS: The overall prevalence of HF in community residents aged ≥ 35 years was 1.06%. Male had significantly higher risk of HF prevalence [odds ratio (OR) = 1.50, P = 0.027]. The gender-adjusted risk of HF was 1.48 times higher per 10 years aging. HF prevalence was statistically associated with atrial fibrillation, valvular heart disease, hypertension and chronic obstructive pulmonary disease after adjusting for age and gender (OR = 8.30, 5.17, 1.11, 2.28, respectively; all P < 0.05). HF incidence in individuals aged ≥ 65 years were 847 per 100,000 person-years. Baseline atrial fibrillation, valvular heart disease, and diabetes mellitus were risk factors for HF incidence for individuals aged ≥ 65 years adjusting for age and gender (OR = 5.05, 3.99, 2.11, respectively; all P < 0.05). Besides, residents with new-onset atrial fibrillation and myocardial infarction were at significantly higher risk of progression to HF (OR = 14.41, 8.54, respectively; all P < 0.05). CONCLUSIONS: Both pre-existing and new-onset cardiovascular diseases were associated with HF incidence in southern China. Management of related cardiovascular diseases may be helpful to reduce the incidence of HF.

4.
J Geriatr Cardiol ; 18(7): 523-533, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34404989

RESUMO

OBJECTIVE: To investigate the prevalence and modifiable risk factors of degenerative valvular heart disease (DVHD) among elderly population in southern China. METHODS: A stratified multistage sampling method was used to recruit subjects. The contents of the survey included the questionnaire, laboratory examination, echocardiography, and other auxiliary examinations. The possible risk factors of DVHD were analyzed by logistic regression analysis. RESULTS: A total of 3538 subjects ≥ 65 years of age were enrolled. One thousand three hundred and seven subjects (36.9%) were diagnosed with DVHD. Degenerative was the most common etiology of VHD. Prevalence of DVHD increased with advancing age. The prevalence of DVHD differed by living region (χ 2 = 45.594, P < 0.001), educational level ( χ 2 = 50.557, P < 0.001), and occupation ( χ 2 = 36.961, P < 0.001). Risk factors associated with DVHD included age (two-fold increased risk for each 10-year increase in age), elevated level C-reactive protein (OR = 1.346, 95% CI: 1.100-1.646), elevated level low density lipoprotein (OR = 1.243, 95% CI: 1.064-1.451), coronary artery disease (OR = 1.651, 95% CI: 1.085-2.513), smoking (OR = 1.341, 95% CI: 1.132-1.589), and hypertension (OR = 1.414, 95% CI: 1.221-1.638). Other significant risk factors included reduced or elevated level red blood cell (OR = 1.347, 95% CI: 1.031-1.761; OR = 1.599, 95% CI: 1.097-2.331; respectively), elevated level platelets (OR = 1.891, 95% CI: 1.118-3.198), elevated level uric acid (OR = 1.282, 95% CI: 1.112-1.479), and stroke (OR: 1.738, 95% CI = 1.085-2.513). CONCLUSIONS: The survey characterized the baseline conditions of DVHD cohort of elderly population in Guangzhou city. The established and emerging risk factors for DVHD may represent challenges and opportunities for therapy.

5.
Proteomics Clin Appl ; 14(2): e1900075, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31579992

RESUMO

PURPOSE: Due to a lack of effective early diagnostic measures, new diagnostic methods for bacterial bloodstream infections (BSIs) are urgently needed. A protein-peptide profiling approach can be used to identify novel diagnostic biomarkers of BSIs. EXPERIMENTAL DESIGN: In this study, MALDI-TOF MS and nano-LC/ESI-MS/MS are used to analyze serum peptides. In addition, GO and network analyses are conducted as a means of analyzing these potential protein markers. Finally, the potential biomarkers are verified in independent clinical samples via ELISA. RESULTS: m/z 1533.8, 2794.3, 3597.3, 5007.3, and 7816.7 reveal an identical trend; the intensity of m/z 1533.8, 2794.3, and 3597.3 are higher in the infection group relative to controls, whereas the intensity of m/z 5007.3 and 7816.7 are lower in the infection group. Four peaks are successfully identified including ITIH4, KNG1, SAA2, and C3. GO and network analyses find these proteins to form an interaction network, which may be correlated with BSI. ELISA results indicate that ITIH4, KNG1, and SAA2 are effective in differentiating infected from normal control group and the febrile group. CONCLUSIONS AND CLINICAL RELEVANCE: These biomarkers have the potential to offer new insights into the signaling networks underlying the development and progression of BSI.


Assuntos
Infecções Bacterianas/sangue , Peptídeos/sangue , Proteômica , Biomarcadores/sangue , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Clin Lab ; 65(12)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31850703

RESUMO

BACKGROUND: In duplex real time quantitative PCR (qPCR), there are several factors affecting the sensitivity of duplex qPCR, such as sharing primer, quantity of the internal control (IC) gene, and the primer dimer (PD). The aim of the study is to find out the relationship of interference among templates with different primer pairs, the internal control gene, and the PD in duplex PCR. METHODS: We designed and synthesized plasmids with partial same sequence and different types of primers include central-homo primer pair, ordinary primer pair, and complementary primer pair. Then we compared the amplification efficiencies of different kinds of primer pairs. Besides, we adjusted the amount of IC plasmid and IC primer to find out the key factor that influences the sensitivity of the target template. RESULTS: The concentration ratios of two plasmids showed interference in sharing the universal primer pair, sharing one forward primer, and sharing no primer were 50:1, 200:1 and 500:1, respectively. The amplification efficiency of the ordinary primer pair was higher than that of the universal primer pair for the plasmid. Sensitivity of the duplex qPCR remained unchanged when the amount of PDs increased, but it declined rapidly when the quantity of the IC increased. CONCLUSIONS: IC is the major factor influencing the sensitivity of the duplex qPCR and it would be better to use one universal primer for IC and target template to achieve minimum interference.


Assuntos
Primers do DNA/genética , Regulação da Expressão Gênica , Plasmídeos/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sequência de Bases , DNA Viral/genética , Hepatite B/diagnóstico , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , Reação em Cadeia da Polimerase em Tempo Real/normas , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
BMC Cardiovasc Disord ; 19(1): 270, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779588

RESUMO

BACKGROUND: To estimate the prevalence of elevated blood glucose level (EBG, including type 2 diabetes mellitus and impaired fasting glucose), and its association with non-valvular atrial fibrillation (NVAF) in Guangzhou, China. METHODS: The population-based follow-up Guangzhou Heart Study collected baseline data from July 2015 to August 2017 among 12,013 permanent residents aged > 35 from 4 Guangzhou districts. Two streets (Dadong and Baiyun) in the Yuexiu District, and one street (Xiaoguwei) and two towns (Xinzao and Nancun) in the Panyu District were chosen as representative of urban and rural areas, respectively. Each participant completed a comprehensive questionnaire, and underwent physical examination, blood sample collection for laboratory testing, electrocardiography, and other evaluations. Multivariable logistic regression analyses were used to estimate the independent association between hyperglycemia and NVAF prevalence. RESULTS: The prevalence of EBG in overall study population was 29.9%. Compared with residents without EBG, the odds ratio (OR) for AF among residents with EBG was significantly higher (1.94, 95% confidence interval [CI]: 1.40-2.70, P <  0.001), even after multivariate adjustment for metabolic abnormalities (OR = 1.60, 95% CI: 1.14-2.25, P = 0.007), and driven by women (OR = 1.80, 95% CI: 1.12-2.91, P = 0.016). CONCLUSIONS: In Guangzhou, China, prevalence of EBG is high among residents aged > 35 years and associated with a multivariate adjusted increase in prevalence of NVAF overall and in women.


Assuntos
Fibrilação Atrial/epidemiologia , Glicemia/análise , Diabetes Mellitus Tipo 2/epidemiologia , Intolerância à Glucose/epidemiologia , Adulto , Fatores Etários , Idoso , Fibrilação Atrial/diagnóstico , Biomarcadores/sangue , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Intolerância à Glucose/sangue , Intolerância à Glucose/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Regulação para Cima
8.
Malar J ; 18(1): 262, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366365

RESUMO

BACKGROUND: The Mindray BC-6800 haematology analyzer (BC-6800) provides a dedicated flag 'Infected RBC' (InR) and the number of InR (InR#)/the permillage of InR (InR‰) in routine blood testing as a screening tool for malaria in endemic areas. This study sought to evaluate the effectiveness of the BC-6800 flag parameter for aiding the diagnosis of malaria. METHODS: A total of 181 samples were tested using the Mindray BC-6800 haematology analyzer, including 117 malaria-infected samples collected from Yunnan, China, and 64 samples from healthy controls. Microscopy examination was conducted as reference when stained thick blood film revealed the presence of malaria parasites identified as Plasmodium vivax and Plasmodium falciparum. The receiver operating characteristic (ROC) curve analysis was developed using Analyse-it v4.92.3. The Kappa value was determined to evaluate the agreement between BC-6800 and light microscopy. RESULTS: The sensitivity of InR‰ generated by BC-6800 for P. vivax and P. falciparum was 88.3 and 24.1%, respectively; specificity of InR‰ for malaria parasites was 84.3 and 84.3%, respectively; positive predictive value and negative predictive value was 89.4 and 82.7% for P. vivax, and 52.8 and 60.3% for P. falciparum. There was a strong correlation between ΔWBC and InR‰ (R2 = 0.9731 for P. vivax and R2 = 0.9757 for P. falciparum). There was also a significant correlation between parasitaemia and InR# in P. vivax-infected samples (R2 = 0.734). InR# was evaluated using ROC curve analysis, the area under the ROC curve is 0.95 with a 95% confidence interval of 0.926 to 0.974, and the cut-off value is 0.01 × 109/L for P. vivax. However, the ring stage and the early trophozoite stage of Plasmodium cannot be detected easily on BC-6800, possibly because of the small size and low nucleic acid content of these stages. CONCLUSIONS: The findings suggest that the flag 'InR' and the parameters 'InR#/InR‰' provided by the BC-6800 haematology analyzer could be used to screen for malaria in a clinical setting.


Assuntos
Análise Química do Sangue/métodos , Sangue/parasitologia , Hematologia/métodos , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , Idoso , Análise Química do Sangue/instrumentação , Criança , Pré-Escolar , China/epidemiologia , Feminino , Hematologia/instrumentação , Humanos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/diagnóstico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Prevalência , Curva ROC , Sensibilidade e Especificidade
9.
Clin Lab ; 65(5)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31115220

RESUMO

BACKGROUND: CYP2D6*10 is mainly responsible for the large pharmacokinetic variability of routinely administered metoprolol in middle-aged and elderly Asian patients. Utilizing an efficient method for identifying the CYP2D6*10 genotypes is clinically important for evaluating the pharmacokinetic effect of administration of metoprolol. This study attempted to evaluate the effectiveness of the two methods used to detect the rs1065852 and rs1135840 SNPs of the CYP2D6*10 gene. METHODS: Blood samples were processed for the collection of genomic DNA from 198 subjects across Chinese population, and detection of CYP2D6*10 (rs1065852 and rs1135840) was performed using the PyroMark Q24 pyrose-quencing and matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS). The discordant results were further validated with Sanger sequencing. We eventually attempted to assess some features of these two methods including reliability, rapidness, being appropriate, and cost-effectiveness. RESULTS: Genotyping of rs1065852 and rs1135840 detected by MALDI-TOF MS were concordant with those identified by PyroMark Q24 pyrosequencing in all 198 (100%) individuals. The hands-on-time and the turnaround time were shorter in the PyroMark Q24 pyrosequencing method than in the MALDI-TOF MS method for SNP of CYP2D6*10. In terms of being cost-effective and high-throughput, the MALDI-TOF MS method outperformed the PyroMark Q24 pyrosequencing method. CONCLUSIONS: CYP2D6*10 genotypes detected by PyroMark Q24 pyrosequencing and MALDI-TOF-MS showed that both methods were reliable, rapid, appropriate, and cost-effective methods. These methods are valuable for clinical applications.


Assuntos
Citocromo P-450 CYP2D6/genética , Técnicas de Genotipagem/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo de Nucleotídeo Único , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Idoso , Anti-Hipertensivos/sangue , Anti-Hipertensivos/metabolismo , Anti-Hipertensivos/uso terapêutico , Povo Asiático/genética , China , Análise Custo-Benefício , Citocromo P-450 CYP2D6/metabolismo , Feminino , Genótipo , Técnicas de Genotipagem/economia , Humanos , Hipertensão/sangue , Hipertensão/tratamento farmacológico , Hipertensão/genética , Masculino , Metoprolol/sangue , Metoprolol/metabolismo , Metoprolol/uso terapêutico , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
10.
Cytokine ; 120: 71-77, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31026733

RESUMO

BACKGROUND: Bacterial bloodstream infection (BSI) remains an important cause of morbidity and mortality, which is a widespread and uncontrolled inflammatory response. There are some cytokines for the auxiliary diagnosis, such as procalcitonin (PCT), C reactive protein (CRP), and interleukin 6 (IL-6), which are not sufficient. This study was aimed to explore a new method of diagnosing bacterial BSI and to find some new biomarkers that could differentiate bloodstream infected patients from healthy people. METHODS: An animal model was used to find relevant changes of peptides in the serum and was validated in clinical samples. Mice (25-27 g) were randomized to infection with Escherichia coli ATCC25922 or phosphate buffer saline. The serum samples were purified by weak cation exchange beads and the serum peptide profiling was established by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Statistical analysis and diagnostic modeling were conducted on BioExplorer. Amino acid sequences of the candidate peptides were identified by nano-liquid chromatography electrospray ionization-tandem mass spectrometry and relevant proteins were recognized on the Uniprot database. The identified proteins were confirmed via enzyme-linked immunosorbent assay on clinical samples. RESULTS: Five peptide peaks (m/z 1941, 2924.1, 3962.1, 4126.9 and 5514) were found as candidate biomarkers for E. coli infection, and the diagnostic model discriminated E. coli infected patients from healthy controls with an accuracy of 92.2%. Peptide peaks m/z 1941, 2924.1 and 4126.9 were identified as the fragments of Serotransferrin (TRF), Complement C3 and Serum amyloid A-1 protein (SAA1), respectively, but only C3 and SAA1 showed significant difference in clinical samples. CONCLUSION: MALDI-TOF MS could be a new method to find the changes of serum peptides after infection, C3 and SAA1 could be new biomarkers in diagnosing BSI.


Assuntos
Biomarcadores/sangue , Diagnóstico Precoce , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/diagnóstico , Peptídeos/sangue , Proteômica , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Aminoácidos , Animais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Camundongos Endogâmicos ICR , Pessoa de Meia-Idade , Peptídeos/química , Curva ROC , Espectrometria de Massas em Tandem
11.
Pharmacol Res ; 143: 73-85, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30862605

RESUMO

Advanced hepatocellular carcinoma (HCC) is a highly aggressive malignancy that is a serious threat to the public health system of China. Urokinase-plasminogen activator (uPA) can promote the invasive growth and metastasis of HCC cells by activating matrix metalloproteinases (MMPs), leading to the breakage of the extra-cellular matrix. uPA is a promising target for advanced HCC treatment. In this stuy the expression of uPA was examined by quantitative polymerase chain reaction in hepatic cell lines. Protein interaction between uPA and SPINK13 was identified by immunoprecipitation. In vitro biochemical assay was used to examine the inhibitory effect of the SPINK13 on the direct cleaving of the recombinant pro-MMP9 by uPA. The antitumor effect of SPINK13 was examined by transwell assay or the nude mice tumor model.The expression of uPA was much higher in highly aggressive HCC cell lines than in lowly aggressive HCC cell lines or non-tumor hepatic cell lines. SPINK13 interacted with uPA in HCC cells and directly inhibited the cleaving of MMP9 by uPA. Treatment of the recombinant SPINK13 protein inhibited the invasion of HCC cells in several experiments, such as transwell experiments or the intrahepatic growth model. The results of the study indicated that SPINK13 could function as a promising therapeutic approach for patients with advanced HCC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Serinopeptidase do Tipo Kazal/uso terapêutico , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Nus , Terapia de Alvo Molecular , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Inibidores de Serinopeptidase do Tipo Kazal/genética , Inibidores de Serinopeptidase do Tipo Kazal/metabolismo , Inibidores de Serinopeptidase do Tipo Kazal/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Cicatrização/efeitos dos fármacos
12.
Biomed Res Int ; 2018: 1238175, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30175112

RESUMO

BACKGROUND: Electroacupuncture (EA) pretreatment plays a protective role in myocardial infarction injury. However, the mechanism of electroacupuncture remains unknown. The aim of this study was to confirm the protective effects of electroacupuncture (EA) on myocardial infarction injury and the possible mechanism. METHODS: Sprague-Dawley (SD) rats, used to serve as acute myocardial infarction (AMI) model, were divided into sham group, model (M) group, M+EA group, AMPK inhibitor Compound C (M+EA+CC), and AMPK inhibitor solvent control (M+EA+DMSO) group, respectively. Rats in EA group were pretreated with EA and those in M+EA+CC group with intravenous AMPK inhibitor Compound C. The myocardial morphological changes and infarct size were observed through HE staining and TTC staining, and the concentrations of CK-MB and LDH were detected using ELISA kits. Transmission electron microscopy was employed to observe the autophagosome formation, and the AMPK-dependent autophagy-related protein expression was detected by immunohistochemistry and western blot. RESULTS: EA could alleviate myocardial infarction injury and decrease the concentrations of CK-MB and LDH. Transmission electron microscopy showed that EA could also regulate the AMPK-dependent autophagosome formation and the AMPK-dependent autophagy-related protein expression. AMPK inhibitor Compound C could impair the effect of EA through regulating the concentrations of CK-MB and LDH, autophagosome formation, and autophagy-related protein expression. CONCLUSION: These results indicated that electroacupuncture could improve myocardial infarction injury and induce autophagy, and AMPK-dependent autophagy might be involved in this process.


Assuntos
Autofagia , Eletroacupuntura , Infarto do Miocárdio/terapia , Isquemia Miocárdica/terapia , Pontos de Acupuntura , Animais , China , Masculino , Ratos , Ratos Sprague-Dawley
13.
J Virol Methods ; 254: 25-30, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29407210

RESUMO

Quantitative PCR (qPCR) assay using TaqMan™ probe was widely used in the detection of different nucleic acids. However, this technology has several drawbacks, including false negative results caused by primer-dimer (PD) and false positive issues due to primer-probe aggregations. Here, we designed a modified TaqMan™-Molecular Beacon probe by adding an antisense base and a new type of primer pair named central-homo primer pairs bearing 5-10 bases homologous sequence on the 3' end. Using the HBV qPCR assay as a proof of concept, the new design significantly improved the accuracy of the TaqMan™ qPCR assay for HBV detection. Application of the central-homo primer pair led to significantly delayed Ct values by 5-10 cycles compared with conventional primer design. The modified probe containing an antisense base did not produce any detectable signal in repeating primer-probe aggregation experiments. Furthermore, the use of the central-homo primer pair and the non-competitive internal control could solve the false negative problem caused by PD formation. We validated this customized duplex qPCR system using 208 clinical samples collected from patients in clinic showing accuracy was higher than that of the conventional qPCR method.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/diagnóstico , Hepatite B/virologia , Reação em Cadeia da Polimerase em Tempo Real , Primers do DNA , Feminino , Humanos , Masculino , Sondas Moleculares , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Life Sci ; 193: 270-281, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29054452

RESUMO

AIM: We aim to investigate the mechanism of aquaporin 4 (AQP 4) up-regulation during high-altitude cerebral edema (HACE) in rats under hypobaric hypoxia and preventative effect of puerarin. METHODS: Rats were exposed to a hypobaric chamber with or without the preventative treatment of puerarin or dexamethasone. Morriz water maze was used to evaluate the spatial memory injury. HE staining and W/D ratio were used to evaluate edema injury. Rat astrocytes and microglia were co-cultured under the condition of hypoxia with the administration of p38 inhibitor, NF-κB inhibitor or puerarin. Interleukin 6 (IL-6) and tumor necrosis factor α (TNF α) of cortex and culture supernatant were measured with ELISA. AQP4, phosphorylation of MAPKs, NF-κB pathway of cortex and astrocytes were measured by Western blot. KEY FINDINGS: Weakened spatial memory and cerebral edema were observed after hypobaric hypoxia exposure. AQP4, phosphorylation of NF-κB and MAPK signal pathway of cortex increased after hypoxia exposure and decreased with preventative treatment of puerarin. Hypoxia increased TNF-α and IL-6 levels in cortex and microglia and puerarin could prevent the increase of them. AQP4 of astrocytes increased after co-cultured with microglia when both were exposed to hypoxia. AQP4 showed a decrease after administered with p38 inhibitor, NF-κB inhibitor or puerarin. SIGNIFICANCE: Hypoxia triggers inflammatory response, during which AQP4 of astrocytes can be up regulated through the release of TNF-α and IL-6 from microglia. Puerarin can exert a preventative effect on the increase of AQP4 through inhibiting the release of TNF-α and phosphorylation of NF-κB, MAPK pathway.


Assuntos
Aquaporina 4/metabolismo , Edema Encefálico/prevenção & controle , Isoflavonas/uso terapêutico , Animais , Aquaporina 4/genética , Astrócitos/metabolismo , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Córtex Cerebral/metabolismo , Dexametasona/metabolismo , Hipóxia/metabolismo , Interleucina-6/metabolismo , Isoflavonas/metabolismo , Isoflavonas/farmacologia , Masculino , Microglia/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
15.
Anal Bioanal Chem ; 410(1): 123-130, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29098334

RESUMO

Unconjugated estriol (uE3) is one of the main naturally occurring estrogens that plays an important role in growth and development of the fetus. Usually, the level of uE3 is very low in men and non-pregnant women, but in pregnant women, the level of estriol has been found to be quite high. Therefore, the combination of uE3, AFP, and hCG is now widely used for Down Syndrome screening as a triple marker. Here, we developed a superparamagnetic lateral flow immunochromatographic assay to quantitatively detect uE3. The detection limit of this assay was 0.86 nmol/L and the linear range for the determination of uE3 was from 1 to 100 nmol/L. The detection time was 15 min and the assay had very low cross-reactivity with estrone (E1), estradiol (E2), and progesterone. The coefficient of variation (CV) of intra- and inter-assay ranged from 5% to 13%. The magnetic signals were stable under 37 °C within 7 d. Moreover, the concentrations of uE3 measured by lateral flow immunochromatographic assay in 230 serum samples collected from pregnant women at the Chinese People's Liberation Army General Hospital had a good correlation with those measured by time-resolved fluorescence immunoassay (R = 0.946).


Assuntos
Cromatografia de Afinidade/métodos , Estriol/sangue , Nanopartículas de Magnetita/química , Biomarcadores/sangue , Síndrome de Down/sangue , Feminino , Humanos , Limite de Detecção , Gravidez , Diagnóstico Pré-Natal
16.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-690672

RESUMO

<p><b>OBJECTIVE</b>To investigate the relationship between plasma miR-93-5p and the risk of esophageal cancer, as well as the influence of miR-93-5p on the biological function of esophageal cancer cells, exerted through exosomes.</p><p><b>METHODS</b>The expression of plasma miR-93-5p in esophageal cancer patients and healthy controls was analysed by real-time quantitative PCR. The influence of miR-93-5p on the risk and prognosis of esophageal carcinoma was analyzed by conditional logistic regression and survival analysis. The effect of miR-93-5p on the biological function of recipient cells was investigated by establishing an in vitro donor cell co-culture model. The target gene of miR-93-5p was validated by luciferase reporter assay and Western Blotting.</p><p><b>RESULTS</b>Upregulation of plasma miR-93-5p expression significantly increases the risk of esophageal cancer and is associated with poor prognosis. miR-93-5p transferred by exosomes promotes the proliferation of recipient esophageal cancer cells and affects the expression of PTEN and its downstream proteins p21 and cyclin D1.</p><p><b>CONCLUSION</b>Our study provides a reference for the identification of biomarkers for the diagnosis and prognosis of esophageal cancer.</p>


Assuntos
Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Comunicação Celular , China , Neoplasias Esofágicas , Exossomos , Fisiologia , MicroRNAs , Metabolismo , PTEN Fosfo-Hidrolase , Genética , Metabolismo , Risco
17.
Environ Pollut ; 213: 977-987, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26873061

RESUMO

Research directions from the 27th conference for Specialists in Air Pollution and Climate Change Effects on Forest Ecosystems (2015) reflect knowledge advancements about (i) Mechanistic bases of tree responses to multiple climate and pollution stressors, in particular the interaction of ozone (O3) with nitrogen (N) deposition and drought; (ii) Linking genetic control with physiological whole-tree activity; (iii) Epigenetic responses to climate change and air pollution; (iv) Embedding individual tree performance into the multi-factorial stand-level interaction network; (v) Interactions of biogenic and anthropogenic volatile compounds (molecular, functional and ecological bases); (vi) Estimating the potential for carbon/pollution mitigation and cost effectiveness of urban and peri-urban forests; (vii) Selection of trees adapted to the urban environment; (viii) Trophic, competitive and host/parasite relationships under changing pollution and climate; (ix) Atmosphere-biosphere-pedosphere interactions as affected by anthropospheric changes; (x) Statistical analyses for epidemiological investigations; (xi) Use of monitoring for the validation of models; (xii) Holistic view for linking the climate, carbon, N and O3 modelling; (xiii) Inclusion of multiple environmental stresses (biotic and abiotic) in critical load determinations; (xiv) Ecological impacts of N deposition in the under-investigated areas; (xv) Empirical models for mechanistic effects at the local scale; (xvi) Broad-scale N and sulphur deposition input and their effects on forest ecosystem services; (xvii) Measurements of dry deposition of N; (xviii) Assessment of evapotranspiration; (xix) Remote sensing assessment of hydrological parameters; and (xx) Forest management for maximizing water provision and overall forest ecosystem services. Ground-level O3 is still the phytotoxic air pollutant of major concern to forest health. Specific issues about O3 are: (xxi) Developing dose-response relationships and stomatal O3 flux parameterizations for risk assessment, especially, in under-investigated regions; (xxii) Defining biologically based O3 standards for protection thresholds and critical levels; (xxiii) Use of free-air exposure facilities; (xxiv) Assessing O3 impacts on forest ecosystem services.


Assuntos
Poluição do Ar , Mudança Climática , Secas , Florestas , Nitrogênio/farmacologia , Ozônio/toxicidade , Árvores/fisiologia , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/farmacologia , Poluentes Atmosféricos/toxicidade , Atmosfera/química , Conservação dos Recursos Naturais , Humanos , Nitrogênio/análise , Pesquisa , Estresse Fisiológico , Árvores/efeitos dos fármacos , Água
18.
Microbes Infect ; 17(1): 54-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25461468

RESUMO

In early 2013, a Bengal tiger (Panthera tigris) in a zoo died of respiratory distress. All specimens from the tiger were positive for HPAI H5N1, which were detected by real-time PCR, including nose swab, throat swab, tracheal swab, heart, liver, spleen, lung, kidney, aquae pericardii and cerebrospinal fluid. One stain of virus, A/Tiger/JS/1/2013, was isolated from the lung sample. Pathogenicity experiments showed that the isolate was able to replicate and cause death in mice. Phylogenetic analysis indicated that HA and NA of A/Tiger/JS/1/2013 clustered with A/duck/Vietnam/OIE-2202/2012 (H5N1), which belongs to clade 2.3.2.1. Interestingly, the gene segment PB2 shared 98% homology with A/wild duck/Korea/CSM-28/20/2010 (H4N6), which suggested that A/Tiger/JS/1/2013 is a novel reassortant H5N1 subtype virus. Immunohistochemical analysis also confirmed that the tiger was infected by this new reassortant HPAI H5N1 virus. Overall, our results showed that this Bengal tiger was infected by a novel reassortant H5N1, suggesting that the H5N1 virus can successfully cross species barriers from avian to mammal through reassortment.


Assuntos
Virus da Influenza A Subtipo H5N1/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/isolamento & purificação , Estruturas Animais/virologia , Animais , Animais de Zoológico , China , Análise por Conglomerados , Modelos Animais de Doenças , Evolução Fatal , Virus da Influenza A Subtipo H5N1/genética , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/virologia , Filogenia , RNA Viral/genética , Vírus Reordenados/genética , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/veterinária , Análise de Sequência de DNA , Homologia de Sequência , Tigres
19.
Wei Sheng Wu Xue Bao ; 47(4): 710-3, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17944378

RESUMO

Streptococcus equi subsp. zooepidemicus belongs to lancefield group C streptococcus, which can cause disease both in animals and humans. It has been associated with a wide variety of serious infections, including meningitis, pneumonia, septic arthritis and mastitis. The M like proteins on the surface of S. equi subsp. zooepidemicus have an antiphagocytic role analogous to that of group A streptococcal M proteins that are essential in establishing infection. In the present study, the M-like gene without partial signal peptide sequence was amplified from genomic DNA of S. equi subsp. zooepidemicus ATCC35246 strain isolated from pig by polymerase chain reaction (PCR). Then the amplified fragment was cloned in the proper orientation into the site between EcoR I and Xho I of pET32-a(+) via restriction endonuclease EcoR I and Xho I. The recombinant plasmid was verified by restriction endonuclease analysis and nucleotide sequencing, then transformed into E. coli BL21. An fusion protein was expressed in BL21 after induced by IPTG, SDS-PAGE analysis showed that the recombinant protein had a molecular weight of 60 kD, Western blotting showed a positive reaction with the antiserum against ATCC35246. To prepare the monoclonal antibodies (McAbs) against the M-like protein, 6-8 weeks old BABL/c mice were immunized endermicly with purified recombinant M-like protein by Ni-nitrilotriacetic acid affinity chromatography. Splenocytes from the immuniszed mice were fused with SP2/0 and indirect ELISA was used to screen hybridoma cells. 12 hybridoma cell lines secreting McAbs against M-like protein of Streptococcus equi subsp. zooepidemicus were generated, and indirect ELISA confirmed that these McAbs only reacted with M-like protein, but not reacted with other bacteria such as group A Streptococci, Streptococcus suis type 2, Streptococcus equi. The indirect ELISA titers of these 12 ascites McAbs were about 2.56 x 10(4) to 1.01 x 10(5) , and the subtype of these McAbs belong to IgG2b, IgG1, IgM. The results of adhersion inhibition showed McAbs 2C8 could inhibit the adhersion of M-like protein to HEp-2 cell.


Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus equi/imunologia , Sus scrofa/microbiologia , Doenças dos Suínos/imunologia , Animais , Aderência Bacteriana , Proteínas da Membrana Bacteriana Externa/genética , Linhagem Celular , Feminino , Humanos , Hibridomas/imunologia , Imunização , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Streptococcus equi/genética , Streptococcus equi/isolamento & purificação , Streptococcus equi/fisiologia , Doenças dos Suínos/microbiologia
20.
Environ Pollut ; 139(3): 515-22, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16098647

RESUMO

Urban atmospheres contain complex mixtures of air pollutants including mutagenic and carcinogenic substances such as benzene, diesel soot, heavy metals and polycyclic aromatic hydrocarbons. In the frame of a European network for the assessment of air quality by the use of bioindicator plants, the Tradescantia micronucleus (Trad-MCN) test was applied to examine the genotoxicity of urban air pollution. Cuttings of Tradescantia clone #4430 were exposed to ambient air at 65 monitoring sites in 10 conurbations employing a standardised methodology. The tests revealed an elevated genotoxic potential mainly at those urban sites which were exposed to severe car traffic emissions. This bioassay proved to be a suitable tool to detect local 'hot spots' of mutagenic air pollution in urban areas. For its use in routine monitoring programmes, however, further standardisation of cultivation and exposure techniques is recommended in order to reduce the variability of results due to varying environmental conditions.


Assuntos
Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental/métodos , Mutagênicos/toxicidade , Saúde da População Urbana/estatística & dados numéricos , Emissões de Veículos/toxicidade , Bioensaio/métodos , Europa (Continente) , Testes para Micronúcleos/métodos , Tradescantia/efeitos dos fármacos , Tradescantia/genética
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