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1.
Molecules ; 27(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35807284

RESUMO

Cephalanthus tetrandrus (Roxb.) Ridsd. et Badh. F. (CT) belongs to the Rubiaceae family. Its dried leaves are widely used in traditional Chinese medicine to treat enteritis, dysentery, toothache, furuncles, swelling, traumatic injury, fracture, bleeding, and scalding. In order to further clarify the unknown chemical composition of CT, a rapid strategy based on UHPLC-Q-exactive orbitrap was established for this analysis using a Thermo Scientific Hypersil GOLDTM aQ (100 mm × 2.1 mm, 1.9 µm) chromatographic column. The mobile phase was 0.1% formic acid water-acetonitrile, with a flow rate of 0.3 mL/min and injection volume of 2 µL; for mass spectrometry, an ESI ion source in positive and negative ion monitoring modes was adopted. A total of 135 chemicals comprising 67 chlorogenic acid derivatives, 48 flavonoids, and 20 anthocyanin derivatives were identified by comparing the mass spectrum information with standard substances, public databases, and the literature, which were all discovered for the first time in this plant. This result broadly expands the chemical composition of CT, which will contribute to understanding of its effectiveness and enable quality control.


Assuntos
Medicamentos de Ervas Chinesas , Rubiaceae , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Espectrometria de Massas/métodos
2.
Br J Clin Pharmacol ; 88(5): 2019-2034, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34820879

RESUMO

Anti-human epidermal growth factor receptor 2 (HER2) therapy is an effective treatment for HER2-positive gastric and breast malignancies. However, the efficacy of HER2-targeted therapy in non-small cell lung cancer (NSCLC) patients with HER2 alterations remains controversial. We searched studies on HER2-targeted therapy in NSCLC patients that reported objective response rate (ORR), disease control rate (DCR) and progressionfree survival (PFS) published from database inception to 30 May 2021. A total of 32 trials involving 958 patients were included. The ORRs of HER2-TKIs targeted therapy, humanised monoclonal antibody, trastuzumab-based treatment and antibody-drug conjugate (ADC) (T-DM1) were 22% (95% CI 11-31), 23% (95% CI 20-65), 26% (95% CI 14-39) and 16% (95% CI _6-37), while that of ADC (DS-8201) was 60% (95% CI 35-85). The DCRs of these groups were 59% (95% CI 49-69), 39% (95% CI _9-88), 63% (95% CI 37-89), 31% (95% CI 4-58) and 87% (95% CI 62-112), respectively. In the subgroup analysis, numerically higher ORRs and DCRs were observed in the poziotinib (38%; 75%) and pyrotinib (35%; 83%) groups. The median PFSs of these groups were 5.51 months, 3.09 months, 4.61 months, 2.65 months and 12.04 months, respectively. HER2-targeted therapy can be considered an acceptable treatment strategy for NSCLC patients with HER2 alterations. In particular, ADC (DS-8201), pyrotinib and poziotinib demonstrated promising anti-tumour activity in HER2-positive NSCLC.


Assuntos
Neoplasias da Mama , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Ado-Trastuzumab Emtansina , Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Receptor ErbB-2/metabolismo , Trastuzumab/uso terapêutico
3.
J Agric Food Chem ; 69(13): 3895-3903, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33759523

RESUMO

Polyhydroxyalkanoates (PHAs) have been reported with agricultural and medical applications in virtue of their biodegradable and biocompatible properties. Here, we systematically engineered three modules for the enhanced biosynthesis of medium-chain-length polyhydroxyalkanoate (mcl-PHA) in Pseudomonas chlororaphis HT66. The phzE, fadA, and fadB genes were deleted to block the native phenazine pathway and weaken the fatty acid ß-oxidation pathway. Additionally, a PHA depolymerase gene phaZ was knocked out to prevent the degradation of mcl-PHA. Three genes involved in the mcl-PHA biosynthesis pathway were co-overexpressed to increase carbon flux. The engineered strain HT4Δ::C1C2J exhibited an 18.2 g/L cell dry weight with 84.9 wt % of mcl-PHA in a shake-flask culture, and the 3-hydroxydodecanoate (3HDD) monomer was increased to 71.6 mol %. Thermophysical and mechanical properties of mcl-PHA were improved with an enriched ratio of 3HDD. This study demonstrated a rational metabolic engineering approach to enhance the production of mcl-PHA with the enriched dominant monomer and improved material properties.


Assuntos
Poli-Hidroxialcanoatos , Pseudomonas chlororaphis , Engenharia Metabólica , Pseudomonas chlororaphis/genética
4.
Biomedicines ; 8(8)2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32764411

RESUMO

Aberrant neutrophil extracellular trap (NET) formation and the loss of barrier integrity in inflamed intestinal tissues have long been associated with inflammatory bowel disease (IBD). However, whether NETs alter intestinal epithelium permeability during colitis remains elusive. Here, we demonstrated that NETs promote the breakdown in intestinal barrier function for the pathogenesis of intestinal inflammation in mouse models of colitis. NETs were abundant in the colon of mice with colitis experimentally induced by dextran sulfate sodium (DSS) or 2,4,6-trinitrobenzene sulfonic acid (TNBS). Analysis of the intestinal barrier integrity revealed that NETs impaired gut permeability, enabling the initiation of luminal bacterial translocation and inflammation. Furthermore, NETs induced the apoptosis of epithelial cells and disrupted the integrity of tight junctions and adherens junctions. Intravenous administration of DNase I, an enzyme that dissolves the web-like DNA filaments of NETs, during colitis restored the mucosal barrier integrity which reduced the dissemination of luminal bacteria and attenuated intestinal inflammation in both DSS and TNBS models. We conclude that NETs serve a detrimental factor in the gut epithelial barrier function leading to the pathogenesis of mucosal inflammation during acute colitis.

5.
J Biosci Bioeng ; 128(5): 525-528, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31178168

RESUMO

Illigera aromatica was fermented by Clonostachys rogersoniana. The acetylcholinesterase (AChE) inhibitory effects of unfermented and fermented I. aromatica revealed that C. rogersoniana-fermented I. aromatica (CFIA) induced significantly more AChE inhibitory activity (IC50: 35.4 ± 2.1 µg/mL). The biotransformation of actinodaphnine (1) into (4R,6aS)-4-hydroxyactinodaphnine (2) was found during the fermentation, which played an important role in the improvement of the AChE inhibitory activity of I. aromatica. Subsequently, the fermentation conditions-including the solid-liquid ratio, fermentation temperature, and fermentation time-were optimized. I. aromatica immersed in 100-200% water and fermented with C. rogersoniana at ambient temperature for 30 days was conducive to the biotransformation of actinodaphnine (1) and improved the AChE inhibitory activity of I. aromatica. The present study provides a novel approach for improving the pharmacological effect of I. aromatica and suggests that CFIA may be used as an alternative AChE inhibitor.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Fermentação , Hernandiaceae/química , Hypocreales/metabolismo , Inibidores da Colinesterase/metabolismo , Hernandiaceae/metabolismo
6.
J Nat Med ; 73(1): 312-317, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30414014

RESUMO

Illigera aromatica S. Z. Huang et S. L. Mo and Illigera henryi W. W. Sm., belonging to the genus Illigera (Hernandiaceae), are used as herbal medicines for promoting blood circulation and treating tuberculosis. Actinodaphnine, the major bioactive alkaloid, plays an important role in the quality controls of the herbs. In the present study, a rapid, simple, accurate, and precise proton quantitative nuclear magnetic resonance (1H-qNMR) method was developed to determine the content of actinodaphnine in I. aromatica and I. henryi. DMSO-d6 enabled satisfactory separation of the signals to be integrated in 1H NMR spectrum. 1,4-Dinitrobenzene was selected as an internal standard. The limits of determination and quantitation were 0.005 and 0.038 mg/mL, respectively. This work implied that 1H-qNMR represents a feasible alternative to HPLC-based methods for quantitation of actinodaphnine in I. aromatica and I. henryi and is suitable for the quality control of I. aromatica and I. henryi.


Assuntos
Plantas Medicinais/química , Espectroscopia de Prótons por Ressonância Magnética/métodos , Prótons
7.
Adv Ther ; 36(2): 451-461, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30554331

RESUMO

INTRODUCTION: Cystic fibrosis (CF) is a progressive, genetic disease that causes persistent lung infections and limits the ability to breathe over time. The combination of a cystic fibrosis transmembrane conductance regulator (CFTR) corrector and potentiator has provided a benefit by decreasing sweat chloride concentration in CF for the F508del-CFTR homozygous mutation, but it remains controversial in lung function, nutritional status, clinical score and safety. METHODS: The authors performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of combination therapy on lung function, nutritional status, clinical score and safety in CF for the F508del-CFTR homozygous mutation. Web of Science, Cochrane Central Register of Controlled Trials, Medline, and Embase were searched. The registered PROSPERO number was CRD42018085875. RESULTS: Five RCTs, including a total of 1637 participants with the F508del-CFTR homozygous mutation who accepted CFTR corrector and potentiator combination therapy along with basic treatment were enrolled in this analysis. Primary analysis revealed that combination therapy improved the percent of predicted FEV1 (ppFEV1) (MD 2.38, 1.62-3.15, P < 0.00001), Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain score (MD 2.59, 0.96-4.22, P = 0.002) and body-mass index (BMI) (MD 0.21, 0.03-0.39, P = 0.02). In the secondary analysis, combination therapy had no impact on the number of participants reporting adverse events (OR 0.88, 0.58-1.33, P = 0.53), but increased the proportion of discontinued treatments due to adverse events (OR 2.71, 1.3-5.63, P = 0.008). CONCLUSIONS: CFTR corrector and potentiator combination therapy effectively improves lung function, nutritional status and clinical score in CF patients with the F508del-CFTR homozygous mutation, and has an acceptable safety profile.


Assuntos
Aminofenóis/administração & dosagem , Aminopiridinas/administração & dosagem , Benzodioxóis/administração & dosagem , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Terapia Combinada , Relação Dose-Resposta a Droga , Homozigoto , Humanos , Mutação , Quinolonas/administração & dosagem
8.
Int J Chron Obstruct Pulmon Dis ; 14: 3003-3015, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920297

RESUMO

Purpose: Mounting evidence suggests that eosinophil levels correlate with the effects of therapy and phenotype for chronic obstructive pulmonary disease (COPD). This study aimed to clarify the relationship between eosinophil levels and clinical outcomes in patients with acute exacerbation of COPD (AECOPD). Methods: A prospective, multicenter, observational cohort study was performed in three teaching hospitals. Patients were grouped by quartile percentage (0, 0.7, 2.55) and absolute blood eosinophils count (0, 0.05×109/L, 0.17×109/L) and divided into four numbered groups ranked from low to high. Results: The study included 493 AECOPD patients. In the percentile-ranked groups, patients in Group 1 experienced significantly longer hospital stays, higher rates of both noninvasive mechanical ventilation (NIMV), and heart failure than those in Group 4 (12 days vs 10 days, p = 0.005; 29.5% vs 23.6%, p = 0.007; 48.4% vs 28.5%, p = 0.001). Group 1 also had higher frequencies of respiratory failure and pulmonary heart disease compared to Groups 3 and 4 (54.8% vs 34.8%, p = 0.002; 54.8% vs 35%, p = 0.003). In the absolute count-ranked groups, patients in Group 1 had significantly higher rates of NIMV than those in Group 3 (41.1% vs 21.7%, p = 0.001), had higher rates of heart failure, respiratory failure, and pulmonary heart disease than those in Group 3 and 4 (48.1% vs 30.2%, p = 0.003; 48.1% vs 30.4%, p = 0.005; 50.8% vs 32.2%, p = 0.004; 50.8% vs 34.1%, p = 0.008; 51.9% vs 34.1%, p = 0.004; 51.9% vs 33%, p = 0.003). There were outcome differences among the admitting hospital of stays in the absolute count groups (p = 0.002), but the differences were not significant in a pairwise comparison. The proportion of ICU admissions and mortality was different in two cohorts with no difference in a pairwise comparison. Conclusion: Patients with lower eosinophil counts experienced poorer clinical outcomes. Eosinophil levels may be a helpful marker to predict outcomes in AECOPD.


Assuntos
Eosinófilos , Contagem de Leucócitos/métodos , Avaliação de Resultados em Cuidados de Saúde , Doença Pulmonar Obstrutiva Crônica , Biomarcadores/análise , China/epidemiologia , Correlação de Dados , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Ventilação não Invasiva/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Valor Preditivo dos Testes , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/terapia , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/etiologia , Exacerbação dos Sintomas
9.
Front Med (Lausanne) ; 6: 282, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921866

RESUMO

Background: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease with different clinical and pathophysiological characteristics. Cumulative evidence shows that eosinophil levels may be connected to the therapeutic effects and phenotype of COPD. However, the prevalence of eosinophilic inflammation in COPD and the baseline characteristics of eosinophilic COPD remain unknown. Our study investigated the prevalence of COPD with eosinophil levels of >2% and the characteristics of eosinophilic COPD. Methods: We searched the Cochrane Central Library, Medline, Embase, and the Web of Science for trials of eosinophil and COPD published from database inception to May 1, 2019. Results: In total, 40,112 COPD patients that were involved in 19 trials were included in the final analysis. The prevalence of eosinophilic COPD ranged from 18.84 to 66.88%, with an average prevalence of 54.95% across all studies. We found that men, ex-smokers, individuals with a history of ischemic heart disease, and individuals with a higher body mass index (BMI) were at higher risk of eosinophilic COPD (OR 1.36, 95% CI 1.26-1.46, P < 0.00001; OR 1.23, 1.12-1.34, P < 0.0001; OR 1.31, 1.14-1.50, P = 0.001; MD 0.70, 0.27-1.12, P = 0.001). There was, however, a lower proportion of GOLD stage I patients among those with eosinophilic COPD (OR 0.84, 0.73-0.96, P = 0.01). No significant differences were found in terms of age, current smoker status, pack-years smoked, percent of predicted forced expiratory volume in 1 s, hypertension, diabetes, or other GOLD stages between the two groups (P > 0.05). Conclusions: Our analysis suggests that eosinophilic inflammation is prevalent in COPD. Eosinophilic COPD was more likely to occur in men, ex-smokers, those with a higher BMI, and those with a high risk of some comorbidity; however, a lower proportion of patients with eosinophilic COPD experienced mild airflow limitations.

10.
BMC Pulm Med ; 18(1): 108, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29954353

RESUMO

BACKGROUND: Vitamin D is involved in the host immune response toward Mycobacterium tuberculosis. However, the efficacy of vitamin D supplementation on sputum conversion, clinical response to treatment, adverse events, and mortality in patients with pulmonary tuberculosis (PTB) remains controversial. We aimed to clarify the efficacy and safety of vitamin D supplementation in PTB treatment. METHODS: We searched Medline, Embase, Cochrane Central Register of Controlled Trials, Web of Science for double-blind, randomized controlled trials of vitamin D supplementation in patients with PTB that reported sputum conversion, clinical response to treatment, adverse events, or mortality, published from database inception to November 26, 2017. This study was registered with PROSPERO, number CRD42018081236. RESULTS: A total of 1787 patients with active PTB receiving vitamin D supplementation along with standard anti-tuberculosis regimen were included in the eight trials with different doses of vitamin D ranging from 1000 IU/day to 600,000 IU/month at different intervals. Primary analysis revealed that vitamin D supplementation increased the proportion of sputum smear and culture conversions (OR 1.21, 95%CI 1.05~ 1.39, z = 2.69, P = 0.007; OR 1.22, 95%CI 1.04~ 1.43, z = 2.41, P = 0.02), but did not improve the time to sputum smear and culture conversions (HR 1.07, 95%CI 0.83~ 1.37, z = 0.50, P = 0.62; HR 0.97, 95%CI 0.76~ 1.23, z = 0.29, P = 0.77). In the secondary analysis, vitamin D improved serum 25(OH)D, plasma calcium concentration, lymphocyte count, and chest radiograph (MD 103.36, 95%CI 84.20~ 122.53, z = 10.57, P < 0.00001; SMD 0.26, 95%CI 0.15~ 0.37, z = 4.61, P < 0.00001; MD 0.09, 95%CI 0.03~ 0.14, z = 2.94, P = 0.003); MD -0.33, 95% CI -0.57~ - 0.08 z = 2.57, P = 0.01), but had no impact on adverse events, mortality and other indicators(TB score, BMI, mean mid-upper arm circumference, weight gain, CRP, ESR, and other blood cells) (P > 0.05). CONCLUSIONS: Vitamin D supplementation can be considered as a combination therapy in patients with PTB.


Assuntos
Suplementos Nutricionais , Tuberculose Pulmonar/tratamento farmacológico , Vitamina D/uso terapêutico , Antituberculosos/uso terapêutico , Humanos , Mycobacterium tuberculosis/efeitos dos fármacos , Escarro/microbiologia , Resultado do Tratamento , Vitamina D/análogos & derivados , Vitamina D/sangue
11.
ScientificWorldJournal ; 2015: 671360, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26171417

RESUMO

Terminal-area aircraft intent inference (T-AII) is a prerequisite to detect and avoid potential aircraft conflict in the terminal airspace. T-AII challenges the state-of-the-art AII approaches due to the uncertainties of air traffic situation, in particular due to the undefined flight routes and frequent maneuvers. In this paper, a novel T-AII approach is introduced to address the limitations by solving the problem with two steps that are intent modeling and intent inference. In the modeling step, an online trajectory clustering procedure is designed for recognizing the real-time available routes in replacing of the missed plan routes. In the inference step, we then present a probabilistic T-AII approach based on the multiple flight attributes to improve the inference performance in maneuvering scenarios. The proposed approach is validated with real radar trajectory and flight attributes data of 34 days collected from Chengdu terminal area in China. Preliminary results show the efficacy of the presented approach.

12.
Parasit Vectors ; 8: 162, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25889184

RESUMO

BACKGROUND: Recent studies have indicated the predominance of Toxoplasma gondii genotype Chinese 1 in animals in China. However, little is known of the genetic features of the parasite in humans. This study aims to determine the prevalence of anti-T. gondii antibodies based on which the genetic character of the parasite was identified in cancer patients in China. METHODS: A total of 1014 serum samples with malignant neoplasms were collected from six tertiary-care hospitals (HAUCM, APH, HAMU, XAH, FHH and HBMC) from January, 2012 to August, 2013. Antibodies against T. gondii were examined by enzyme-linked immunosorbent assay (ELISA). Blood samples were subsequently used for PCR assay to detect T. gondii DNA (gra6). The DNA positive samples were subjected to genotyping using a multiplex multilocus nested PCR-RFLP at 10 loci, including sag1, sag2, sag3, btub, gra6, l358, c22-8, c29-2, pk1 and apico. Samples from the patients were anonymous and only data with regard to age and gender was available at sample collection. RESULTS: Overall, 8.38% (85/1014) of the examined patients showed positive antibodies against T. gondii. Among them, 61 (6.02%) were seropositive only for IgG, 16 (1.58%) were only for IgM, and 8 (0.79%) were found to be positive for both IgG and IgM. The seroprevalence of antibodies to Toxoplasma ranged from 5.8% to 11.0%, without regional difference (χ(2) = 4.764, P = 0.445). No significant differences of the positive rates of T. gondii infection were noted in genders (male, 8.96%; female, 7.45%) (χ(2) = 0.707, P = 0.400) and in ages (χ(2) = 1.172, P = 0.947). Of 1014 DNA samples, 36 (3.55%) were positive for T. gondii by nested PCR at gra6 locus and nine gave rise to complete genotyping results. All samples with achieved PCR-RFLP genotyping showed a common genetic character of type Chinese 1 (ToxoDB#9). CONCLUSION: Seroprevalence of toxoplasmosis in immunosuppressed individuals is rarely reported in China and we presented a positive rate of 8.38% in cancer patients. Toxoplasma genomic DNA genotyping demonstrated a common genetic character of Chinese 1, indicating a possible pathogenic origin of animals in human infection.


Assuntos
Neoplasias/complicações , Estudos Soroepidemiológicos , Toxoplasma/genética , Toxoplasmose/parasitologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Anticorpos Antiprotozoários/sangue , China/epidemiologia , Feminino , Genótipo , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Toxoplasmose/epidemiologia
13.
PLoS One ; 9(11): e112683, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25393306

RESUMO

Epigallocatechin gallate (EGCG) is a major polyphenol in green tea with beneficial effects on the impairment in learning and memory. Autophagy is a cellular process that protects neurons from stressful conditions. The present study was designed to investigate whether EGCG can rescue chronic unpredictable mild stress (CUMS)-induced cognitive impairment in rats and whether its protective effect involves improvement of autophagic flux. As expected, our results showed that CUMS significantly impaired memory performance and inhibited autophagic flux as indicated by elevated LC3-II and p62 protein levels. At the same time, we observed an increased neuronal loss and activated mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6k) signaling in the CA1 regions. Interestingly, chronic treatment with EGCG (25 mg/kg, i.p.) significantly improved those behavioral alterations, attenuated histopathological abnormalities in hippocampal CA1 regions, reduced amyloid beta1-42 (Aß1-42) levels, and restored autophagic flux. However, blocking autophagic flux with chloroquine, an inhibitor of autophagic flux, reversed these effects of EGCG. Taken together, these findings suggest that the impaired autophagy in CA1 regions of CUMS rats may contribute to learning and memory impairment. Therefore, we conclude that EGCG attenuation of CUMS-induced learning and memory impairment may be through rescuing autophagic flux.


Assuntos
Catequina/análogos & derivados , Disfunção Cognitiva/tratamento farmacológico , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Nootrópicos/farmacologia , Estresse Psicológico/tratamento farmacológico , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Autoantígenos/genética , Autoantígenos/metabolismo , Autofagia/efeitos dos fármacos , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Catequina/antagonistas & inibidores , Catequina/farmacologia , Cloroquina/farmacologia , Doença Crônica , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/fisiopatologia , Regulação da Expressão Gênica , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Nootrópicos/antagonistas & inibidores , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Wistar , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Estresse Psicológico/complicações , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
14.
Parasit Vectors ; 6: 273, 2013 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-24330536

RESUMO

BACKGROUND: Recent studies of Toxoplasma gondii isolates from animals in different regions of China have shown a limited genetic diversity and type China 1 was the dominant genotype of T. gondii prevalent in Chinese animals. However, little has been known concerning the isolation and genotyping of T. gondii circulating in chickens, pigs and rodents in China. The aim of the study was to characterize samples of T. gondii isolates obtained from naturally infected cats, pigs and free-range chickens slaughtered for human consumption in China. METHODS: In the present study, brain tissues of 77 animals collected from different areas of China, including 24 free-range chickens (Gallus domesticus) , 13 voles (Rattus flavipectus), 23 pigs and 17 cats, were bioassayed in mice and viable T. gondii were isolated from the brains of eleven. These eleven T. gondii isolates were maintained in Kunming (KM) outbred mice and DNA isolated from tissues of infected mice was characterized using 11 PCR-restriction fragment length polymorphism (PCR-RFLP) markers: SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3. Moreover, to determine mouse virulence of China 1 lineage of parasites, a TgCtgy5 genotype isolate was selected randomly and assessed in KM mice with different inoculation doses. RESULTS: Results of genotyping revealed that ten isolates were type China 1 (ToxoDB PCR-RFLP genotype #9), and TgCksz1 was a new genotype that was reported for the first time designated here as ToxoDB PCR-RFLP #225. No clonal types I, II and III lineages were found. DNA sequencing of four introns (EF1, HP2, UPRT1 and UPRT7) and two genes (GRA6 and GRA7) from representative isolates confirmed the results of PCR-RFLP genotyping. The TgCtgy5 isolate was highly virulent in KM mice; all infected mice died of acute toxoplasmosis, irrespective of the inoculation dose. The results indicate that mouse virulent isolates of T. gondii are predominantly circulating in cats in China. CONCLUSIONS: T. gondii isolated from chickens, pigs, cats and rodents in different locations in China were genotyped and the results reconfirmed the limited diversity of T. gondii in China and showed that type China 1 lineage was dominant in this country.


Assuntos
Doenças das Aves Domésticas/parasitologia , Doenças dos Suínos/parasitologia , Toxoplasma/genética , Toxoplasma/patogenicidade , Toxoplasmose Animal/parasitologia , Animais , Arvicolinae , Encéfalo/parasitologia , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Gatos , Galinhas , China/epidemiologia , Variação Genética , Genótipo , Doenças das Aves Domésticas/epidemiologia , Suínos , Doenças dos Suínos/epidemiologia , Toxoplasmose Animal/epidemiologia , Virulência
15.
Physica A ; 389(18): 3922-3931, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32288080

RESUMO

With the rapid development of the economy and the accelerated globalization process, the aviation industry plays a more and more critical role in today's world, in both developed and developing countries. As the infrastructure of aviation industry, the airport network is one of the most important indicators of economic growth. In this paper, we investigate the evolution of the Chinese airport network (CAN) via complex network theory. It is found that although the topology of CAN has remained steady during the past few years, there are many dynamic switchings inside the network, which have changed the relative importance of airports and airlines. Moreover, we investigate the evolution of traffic flow (passengers and cargoes) on CAN. It is found that the traffic continues to grow in an exponential form and has evident seasonal fluctuations. We also found that cargo traffic and passenger traffic are positively related but the correlations are quite different for different kinds of cities.

16.
Protein J ; 28(9-10): 448-56, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19921411

RESUMO

Kinetic changes of alpha-glucosidase from Saccharomyces cerevisiae in guanidinium chloride (GdmCl) and SDS solutions were investigated. The results showed both denaturants can lead conformational changes and loss of enzymatic activities. However, the concentrations of denaturants causing loss of activities were much lower than that of conformational changes, which suggested that the conformation of active site of alpha-glucosidase was more fragile than the whole molecular conformation in response to the two denaturants. According to the different kinetic process of the enzyme in the GdmCl and SDS solutions, the further investigation on the process of denaturation were made, it showed GdmCl and SDS had different types of inhibition and different types of interaction with the enzyme. Furthermore, the mechanisms of the two denaturants were discussed.


Assuntos
Saccharomyces cerevisiae/enzimologia , alfa-Glucosidases/química , Guanidina/química , Cinética , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Dodecilsulfato de Sódio/química , Tensoativos/química
17.
IEEE Trans Neural Netw ; 20(12): 1911-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19822474

RESUMO

This paper presents a new wrapper-based feature selection method for multilayer perceptron (MLP) neural networks. It uses a feature ranking criterion to measure the importance of a feature by computing the aggregate difference, over the feature space, of the probabilistic outputs of the MLP with and without the feature. Thus, a score of importance with respect to every feature can be provided using this criterion. Based on the numerical experiments on several artificial and real-world data sets, the proposed method performs, in general, better than several selected feature selection methods for MLP, particularly when the data set is sparse or has many redundant features. In addition, as a wrapper-based approach, the computational cost for the proposed method is modest.


Assuntos
Sistemas de Gerenciamento de Base de Dados , Redes Neurais de Computação , Percepção/fisiologia , Probabilidade , Algoritmos , Simulação por Computador , Técnicas de Apoio para a Decisão , Humanos
18.
IEEE Trans Biomed Eng ; 56(2): 336-44, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19272915

RESUMO

An automatic electroencephalogram (EEG) artifact removal method is presented in this paper. Compared to past methods, it has two unique features: 1) a weighted version of support vector machine formulation that handles the inherent unbalanced nature of component classification and 2) the ability to accommodate structural information typically found in component classification. The advantages of the proposed method are demonstrated on real-life EEG recordings with comparisons made to several benchmark methods. Results show that the proposed method is preferable to the other methods in the context of artifact removal by achieving a better tradeoff between removing artifacts and preserving inherent brain activities. Qualitative evaluation of the reconstructed EEG epochs also demonstrates that after artifact removal inherent brain activities are largely preserved.


Assuntos
Artefatos , Inteligência Artificial , Eletroencefalografia/métodos , Modelos Cardiovasculares , Processamento de Sinais Assistido por Computador , Algoritmos , Piscadela , Erros de Diagnóstico , Eletrocardiografia , Humanos , Reprodutibilidade dos Testes
19.
Clin Neurophysiol ; 119(7): 1524-33, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18468483

RESUMO

OBJECTIVE: Automatic measurement and monitoring of mental fatigue are invaluable for preventing mental-fatigue related accidents. We test an EEG-based mental-fatigue monitoring system using a probabilistic-based support vector-machines (SVM) method. METHODS: Ten subjects underwent 25-h sleep deprivation experiments with EEG monitoring. EEG data were segmented into 3-s long epochs and manually classified into 5 mental-fatigue levels, based on subjects' performance on an auditory vigilance task (AVT). Probabilistic-based multi-class SVM and standard multi-class SVM were compared as classifiers for distinguishing mental fatigue into the 5 mental-fatigue levels. RESULTS: Accuracy of the probabilistic-based multi-class SVM was 87.2%, compared to 85.4% using the standard multi-class SVM. Using confidence estimates aggregation, accuracy increased to 91.2%. CONCLUSIONS: Probabilistic-based multi-class SVM not only gives superior classification accuracy but also provides a valuable estimate of confidence in the prediction of mental fatigue level in a given 3-s EEG epoch. SIGNIFICANCE: The work demonstrates the feasibility of an automatic EEG method for assessing and monitoring of mental fatigue. Future applications of this include traffic safety and other domains where measurement or monitoring of mental fatigue is crucial.


Assuntos
Eletroencefalografia , Fadiga Mental/fisiopatologia , Algoritmos , Nível de Alerta/fisiologia , Percepção Auditiva/fisiologia , Intervalos de Confiança , Interpretação Estatística de Dados , Humanos , Fadiga Mental/psicologia , Modelos Estatísticos , Privação do Sono/fisiopatologia , Privação do Sono/psicologia , Software
20.
IEEE Trans Biomed Eng ; 54(7): 1231-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17605354

RESUMO

Two feature selection approaches for multilevel mental fatigue electroencephalogram (EEG) classification are presented in this paper, in which random forest (RF) is combined with the heuristic initial feature ranking scheme (INIT) or with the recursive feature elimination scheme (RFE). In a "leave-one-proband-out" evaluation strategy, both feature selection approaches are evaluated on the recorded mental fatigue EEG time series data from 12 subjects (each for a 25-h duration) after initial feature extractions. The latter of the two approaches performs better both in classification performance and more importantly in feature reduction. RF with RFE achieved its lowest test error rate of 12.3% using 24 top-ranked features, whereas RF with INIT reached its lowest test error rate of 15.1% using 64 top-ranked features, compared to a test error rate of 22.1% using all 304 features. The results also show that 17 key features (out of 24 top-ranked features) are consistent between the subjects using RF with RFE, which is superior to the set of 64 features as determined by RF with INIT.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiopatologia , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Fadiga Mental/diagnóstico , Fadiga Mental/fisiopatologia , Reconhecimento Automatizado de Padrão/métodos , Adulto , Nível de Alerta , Inteligência Artificial , Potenciais Evocados , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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