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1.
Artigo em Inglês | MEDLINE | ID: mdl-37167094

RESUMO

Two moderately halotolerant bacterium strains, designated PJ-16T and PJ-38, were isolated from a tidal flat of the red beach in Panjin City, Liaoning Province, PR China. Cells were found to be Gram-stain-negative, aerobic, motile, rod-shaped with a single polar flagellum. Optimum growth of strain PJ-16T occurred at 30 °C, pH 7.0 and 0.2-8.0  % (w/v) NaCl, and strain PJ-38 at 30 °C, pH 6.0-7.0 and 0.2-8.0  % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PJ-16T was most closely related to Marinobacter denitrificans KCTC 62941T (99.2 % 16S rRNA gene sequence similarity), Marinobacter algicola DSM 16394T (98.6 %), Marinobacter salarius JCM 19399T (98.4 %) and Marinobacter confluentis KCTC 42705T (98.2 %), and strain PJ-38 was most closely related to M. denitrificans KCTC 62941T (99.1 %), M. algicola DSM 16394T (98.6 %), M. salarius JCM 19399T (98.4 %) and M. confluentis KCTC 42705T (98.1 %). The G+C content of the genomic DNA of strain PJ-16T based on its draft genomic sequence was 57.4 mol%. The major cellular fatty acids of strain PJ-16T were C16 : 0, C16 : 1 ω7c/C16 : 1 ω6c and C18 : 1 ω9c. The major respiratory quinone of PJ-16T was ubiquinone-9 and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The results of the phenotypic, phylogenetic and genomic analyses revealed that strains PJ-16T and PJ-38 represent a novel species of the genus Marinobacter, and the name Marinobacter panjinensis sp. nov. is proposed. The type strain is PJ-16T (= CGMCC 1.13694T= KCTC 72023T).


Assuntos
Ácidos Graxos , Marinobacter , Ácidos Graxos/química , Fosfolipídeos/química , Água do Mar/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Cloreto de Sódio , DNA Bacteriano/genética , Análise de Sequência de DNA , Composição de Bases , Técnicas de Tipagem Bacteriana
2.
Zhongguo Zhong Yao Za Zhi ; 44(8): 1564-1572, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-31090320

RESUMO

To establish an HPLC characteristic fingerprint method of Fuke Qianjin Capsules,and determine the contents of its main components. The analysis was carried out on a Kromasil 100-5-C18 analytical column(4. 6 mm ×250 mm,5 µm) with gradient elution by acetonitrile(A)-0. 1% phosphoric acid aqueous solution(B),a flow rate at 1. 0 m L·min-1 and the detection wavelength of 254 nm.The column temperature was 30 ℃,and the injection volume was 10 µL. The determination method of genistin,jatrorrhizine,andrographolide and 14-deoxy-11,12-didehydroandrographolide index components were studied methodologically. The common mode of the characteristic fingerprint of Fuke Qianjin Capsules was set up with 8 common peaks,which were identified as genistin,jatrorrhizine,palmatine,berberine,andrographolide,14-deoxy-11,12-didehydroandrographolide,Z-ligustilide,and Z-3-butylidenephthalide,respectively,in comparison with the references. The similarities of 20 batches of Fuke Qianjin Capsules samples were above 0. 95. All of the above-mentioned 4 analytes could be well separated under the optimized chromatographic conditions. RSD of precision and repeatability experiment were both less than 1. 5%,and the sample solution was stable during 72 h. All of the compounds had a good linearity and linear range. The contents of genistin,jatrorrhizine,andrographolide,and 14-deoxy-11,12-didehydroandrographolide in 20 batches of Fuke Qianjin Capsules samples were 28. 66-56. 04,94. 77-197. 92,1 705. 33-4 148. 93 and 462. 16-1 225. 96 µg in each capsule,respectively. The developed HPLC characteristic fingerprint and quantitative analysis methods were reliable,accurate and sensitive,and could be used effectively evaluate the quality of Fuke Qianjin Capsules samples.


Assuntos
Medicamentos de Ervas Chinesas/química , Compostos Fitoquímicos/análise , Cápsulas , Cromatografia Líquida de Alta Pressão
3.
J Vet Diagn Invest ; 30(6): 848-854, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30239308

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a highly contagious respiratory virus causing severe morbidity in pigs worldwide. Control strategies for PRRSV often rely on detecting PRRSV, culling or isolating sick pigs, disinfecting pig barns, vaccination, and monitoring for virus spread. Given the high economic impact of PRRSV on pig farms, there is a great need for rapid and reliable PRRSV detection assays. We compared the performance of 2 commercial reverse-transcription real-time PCR (RT-rtPCR) assays, the VetMAX PRRSV NA and EU reagents (ABI assay) and the PRRSV general RT-rtPCR kit (Anheal assay), for the molecular detection of PRRSV in sera collected from pigs in China. Between June and September 2015, sera were collected from 219 healthy and 104 suspected PRRSV-infected pigs on 4 farms in China. Employing blinding, the 2 assays were run by 2 laboratories (Guangzhou Animal Health Inspection Institute [GAHII] and Sun Yat-sen University [SYSU] laboratories) and compared. Although both assays detected PRRSV with 100% specificity at both laboratories, the sensitivity (95% vs. 78% at GAHII; 94% vs. 72% at SYSU Laboratory) and the reproducibility (kappa value 0.933 vs. 0.931) were slightly better for the ABI assay compared to the Anheal assay.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/diagnóstico , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Animais , China , Feminino , Masculino , Síndrome Respiratória e Reprodutiva Suína/sangue , Síndrome Respiratória e Reprodutiva Suína/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/instrumentação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Suínos
4.
Zhongguo Zhong Yao Za Zhi ; 43(11): 2300-2312, 2018 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29945383

RESUMO

Fukeqianjin formula, a traditional Chinese medicine compound, consists of eight Chinese medicinal materials including roots of Moghania macrophylla, roots of Rosa laevigata, aerial parts of Andrographis paniculata, caulis of Mahonia fortunei, roots of Zanthoxylum dissitum, roots of Angelica sinensis, caulis of Spatholobus suberectus, and roots of Codonopsis pilosula. The chemical constituents from Fukeqianjin formula were studied in this paper. The compounds were separated and purified by repeated column chromatographic methods including silica gel, Sephadex LH-20, macroporous adsorptive resin, and reverse phase high performance liquid chromatography. And their chemical structures were determined by spectral data analyses. Thirty-eight compounds were obtained and identified as Z-3-butylidenephthalide (1), Z-ligustilide (2), senkyunolide I (3), senkyunolide H (4), vanillin (5), 7-O-methylwogonin (6), wogonin (7), panicolin (8), 19-hydroxy-8(17),13-labdadien-15,16-olide (9), andrograpanin (3,14-dideoxyandrographolide; 10), andrographolide (11), 14-deoxy-11,12-didehydroandrographolide (12), isoandrographolide (13), andrographin (2'-O-methylskullcapflavone, 14), biochanin A (15), 5-hydroxy-7,8,2',5'-tetramethoxyflavone (16), formononetin (17), daidzein (18), genistein (19), benzoic acid (20), vanillic acid (21), trans-ferulic acid (22), salicylic acid (23), daidzin (24), genistein-7-O-ß-D-apiofuranosyl-(1→6)-O-ß-D-glucopyranoside (25), apigenin-7-O-ß-D-glucuronide (26), andrographidin C (27), apigenin-7-O-ß-D-(6"-methyl)glucuronide (28), neoandrographolide (29), genistin (30), andrographiside (31), 14-deoxy-11,12-didehydroandrographiside (32), lobetyolin (33), epicatechin (34), catechin (35), palmatine (36), berberine (37), and jatrorrhizine (38), respectively. From the results of an individual medicinal material studies, it can be judged that compounds 17, 19, 24 and 30 as flavonoids came from the roots of M. macrophylla, compounds 36-38 as alkaloids came from the caulis of M. fortunei, compounds 6-8, 14, 16, and 27 as flavonoids as well as 9-13, 29, 31, and 32 as diterpenes came from the aerial parts of A. paniculata, compound 5 as phenols came from the roots of Z. dissitum, compounds 1-4 as phthalides as well as compound 22 as phenylpropanoids came from the roots of A. sinensis, compound 33 as alkynes came from the roots of C. pilosula, compounds 15, 17-19 as flavonoids as well as compound 21 as phenolic acids came from the caulis of S. suberectus. While compounds 34 and 35 as flavanoids could come from both the caulis of S. suberectus and roots of R. laevigata. The chemical composition of traditional Chinese medicine compound can be tracked from the original sources. This work provides a demonstration for the material basis study of traditional Chinese medicine compound. Compounds 25, 26 and 28 have not so far been isolated and identified from the above-mentioned single herb.


Assuntos
Medicamentos de Ervas Chinesas/química , Compostos Fitoquímicos/análise , Plantas Medicinais/química , Alcaloides/análise , Flavonoides/análise , Medicina Tradicional Chinesa , Raízes de Plantas/química
5.
Molecules ; 23(3)2018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29518051

RESUMO

Alzheimer's disease (AD) is an age-related neurodegenerative disease that is mediated by multiple signaling pathways. In recent years, the components of Psoralea Fructus (PF) have demonstrated some anti-Alzheimer effects both in vitro and in vivo. To further reveal the active compounds of PF and their mechanisms regulating key targets of AD, in this study, we identified four prenylated compounds from the 70% ethanolic aqueous extract of PF, namely bavachin, bavachinin, bavachalcone, and isobavachalcone. Multi-target bioactivity analysis showed that these compounds could differentially inhibit neuroinflammation, oxidative damage, and key AD-related protein targets, such as amyloid ß-peptide 42, ß-secretase, glycogen synthase kinase 3ß, and acetylcholinesterase. These compounds may generate beneficial effects in AD prevention and treatment.


Assuntos
Extratos Vegetais/química , Extratos Vegetais/farmacologia , Psoralea/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Compostos Fitoquímicos , Extratos Vegetais/isolamento & purificação , Prenilação , Agregados Proteicos/efeitos dos fármacos , Ratos
6.
Phytomedicine ; 38: 166-174, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29425649

RESUMO

BACKGROUND: The fruit of Psoralea corylifolia L., Psoraleae fructus (PF), is widely used in traditional Chinese medicine as a well-known herbal tonic. Previous studies have shown that PF and its major constituents may have potential values in the treatment of Parkinson and Alzheimer diseases, though their pharmacokinetics and brain distribution were largely unknown. PURPOSE: To develop a liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for simultaneous studies of the plasma pharmacokinetics and cerebral nuclei (including cerebellum, thalamus, brainstem, hippocampus, corpus striatum and cortex) distribution in rats of eleven known PF compounds following as psoralen, isopsoralen, psoralidin, bavachin, bavachinin, isobavachin, isobavachalcone, bavachalcone, neobavaisoflavone, corylifol A, and corylin. METHODS: Rats were orally administered via gavage at a single dose of PF extract at 1.2 g/kg. The eleven known PF compounds were extracted from rat plasma and cerebral nuclei at different time points, and then determined by the established LC-MS/MS method. Non-compartmental pharmacokinetic profiles were calculated, and the distribution in rat plasma and cerebral nuclei were compared. RESULTS: The results showed that all the tested compounds were quickly absorbed into rat plasma and distributed almost evenly to the cerebral nuclei. The distribution concentrations at different nuclei varied at one determined time point, but the overall trends were basically similar to the plasma concentration-time results. Psoralen and isopsoralen, the two highest coumarins contained in PF, displayed far higher plasma concentrations (AUC0→∞, plasma≈53,884∼65,578 ng·h/ml) and central nervous system penetration (AUC0→∞, brain nuclei ≈44,659∼65,823 ng·h/g) than the prenylflavonoids (other compounds except psoralidin, AUC0→∞, plasma≈69∼324 ng·h/ml; AUC0→∞, brain nuclei ≈119∼3662 ng·h/g). However, the total brain-to-plasma ratios of the prenylflavonoids were higher than the coumarins, suggesting the prenylflavonoids can more readily enter the brain than the coumarins. CONCLUSION: The established LC-MS/MS method is sensitive and specific for the simultaneous quantitation of the eleven PF compounds in rat plasma and cerebral nuclei. The results of plasma pharmacokinetics and cerebral nuclei distribution may reveal the possible substance basis for the CNS activities of PF, and highlight the application possibility of PF and its major constituents in the treatment of Parkinson and Alzheimer diseases.


Assuntos
Encéfalo/efeitos dos fármacos , Extratos Vegetais/farmacocinética , Administração Oral , Animais , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Fabaceae , Masculino , Extratos Vegetais/sangue , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Distribuição Tecidual
7.
Molecules ; 23(1)2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29346315

RESUMO

Alzheimer's disease (AD) is a serious threat for the aging society. In this study, we examined the preventive effect of the total prenylflavonoids (TPFB) prepared from the dried fruits of Psoralea corylifolia L., using an age-related AD mouse model SAMP8. We found that long-term dietary TPFB at 50 mg/kg·day significantly improved cognitive performance of the SAMP8 mice in Morris water maze tests, similar to 150 mg/kg·day of resveratrol, a popular neuro-protective compound. Furthermore, TPFB treatment showed significant improvements in various AD markers in SAMP8 brains, which were restored to near control levels of the normal mice, SAMR1. TPFB significantly reduced the level of amyloid ß-peptide 42 (Aß42), inhibited hyperphosphorylation of the microtubule-associated protein Tau, induced phosphorylation of Ser9 of the glycogen synthase kinase 3ß (GSK-3ß), and decreased the expression of the proinflammatory cytokines TNFα, IL-6, and IL-1ß. Finally, TPFB also markedly reduced the level of serum derivatives of reactive oxygen metabolites (d-ROMs), a biomarker of oxidative stress in vivo. These results showed that dietary TPFB could effectively prevent age-related cognitive deficits and AD-like neurobiochemical changes, and may have a potential role in the prevention of Alzheimer's disease.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Ração Animal , Disfunção Cognitiva , Flavonoides/química , Frutas/química , Psoralea/química , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Animais , Biomarcadores , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Citocinas/metabolismo , Modelos Animais de Doenças , Flavonoides/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Camundongos , Estrutura Molecular , Fragmentos de Peptídeos/metabolismo , Fosforilação/efeitos dos fármacos , Agregados Proteicos/efeitos dos fármacos , Resveratrol , Estilbenos/química , Proteínas tau/metabolismo
8.
Appl Microbiol Biotechnol ; 100(21): 9111-9124, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27236811

RESUMO

Eubacterium limosum ZL-II was described to convert secoisolariciresinol (SECO) to its demethylating product 4,4'-dihydroxyenterodiol (DHEND) under anoxic conditions. However, the reaction cascade remains unclear. Here, the O-demethylase being responsible for the conversion was identified and characterized. Nine genes encoding two methyltransferase-Is (MT-I), two corrinoid proteins (CP), two methyltransferase-IIs (MT-II), and three activating enzymes (AE) were screened, cloned, and expressed in Escherichia coli. Four of the nine predicted enzymes, including ELI_2003 (MT-I), ELI_2004 (CP), ELI_2005 (MT-II), and ELI_0370 (AE), were confirmed to constitute the O-demethylase in E. limosum ZL-II. The complete O-demethylase (combining the four components) reaction system was reconstructed in vitro. As expected, the demethylating products 3-demethyl-SECO and DHEND were both produced. During the reaction process, ELI_2003 (MT-I) initially catalyzed the transfer of methyl group from SECO to the corrinoid of ELI_2004 ([CoI]-CP), yielding demethylating products and [CH3-CoIII]-CP; then ELI_2005 (MT-II) mediated the transfer of methyl group from [CH3-CoIII]-CP to tetrahydrofolate, forming methyltetrahydrofolate and [CoI]-CP. Due to the low redox potential of [CoII]/[CoI], [CoI]-CP was oxidized to [CoII]-CP immediately in vitro, and ELI_0370 (AE) was responsible for catalyzing the reduction of [CoII]-CP to its active form [CoI]-CP. The active-site residues in ELI_2003, ELI_2005, and ELI_0370 were subsequently determined using molecular modeling combined with site-directed mutagenesis. To our knowledge, this is the first study on the identification and characterization of a four-component O-demethylase from E. limosum ZL-II, which will facilitate the development of method to artificial synthesis of related bioactive chemicals.


Assuntos
Eubacterium/enzimologia , Oxirredutases O-Desmetilantes/genética , Oxirredutases O-Desmetilantes/metabolismo , Clonagem Molecular , Escherichia coli , Eubacterium/genética , Eubacterium/isolamento & purificação , Trato Gastrointestinal/microbiologia , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
9.
J Phys Condens Matter ; 28(17): 175301, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27028266

RESUMO

Employing the Green's function method, we investigate the Josephson current through a quantum dot side coupled to a topological superconducting nanowire sustaining a pair of Majorana zero modes. It is found that the Josephson current is blocked when the quantum dot is side coupled to a superconducting nanowire in a topologically trivial phase. However, when the topological superconducting nanowire transitions from a topologically trivial to a topologically non-trivial phase, an Andreev bound state arises at the zero Fermi energy of the quantum dot due to leakage of the Majorana zero mode. Thus a Josephson current can be induced by leakage of the Majorana zero mode into the quantum dot. The Josephson current shows a plateau-like structure and a clear-cut trivial/non-trivial phase transition, as a function of a Zeeman field imposed on the system. The transition and plateau-like structure can be used to probe the existence of the Majorana zero mode. The current-phase relation has also been studied.

10.
Sci Rep ; 5: 14892, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26450824

RESUMO

The quantum entanglement between two qubits is crucial for applications in the quantum communication. After the entanglement of photons was experimentally realized, much effort has been taken to exploit the entangled electrons in solid-state systems. Here, we propose a Cooper-pair splitter, which can generate spatially-separated but entangled electrons, in a quantum anomalous Hall insulator proximity-coupled with a superconductor. After coupling with a superconductor, the chiral edge states of the quantum anomalous Hall insulator can still survive, making the backscattering impossible. Thus, the local Andreev reflection becomes vanishing, while the crossed Andreev reflection becomes dominant in the scattering process. This indicates that our device can serve as an extremely high-efficiency Cooper-pair splitter. Furthermore, because of the chiral characteristic, our Cooper-pair splitter is robust against disorders and can work in a wide range of system parameters. Particularly, it can still function even if the system length exceeds the superconducting coherence length.

11.
BMC Cardiovasc Disord ; 14: 59, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24886422

RESUMO

BACKGROUND: Previous studies indicate that decreased heart-rate variability (HRV) is related to the risk of death in patients after acute myocardial infarction (AMI). However, the conventional indices of HRV have poor predictive value for mortality. Our aim was to develop novel predictive models based on support vector machine (SVM) to study the integrated features of HRV for improving risk stratification after AMI. METHODS: A series of heart-rate dynamic parameters from 208 patients were analyzed after a mean follow-up time of 28 months. Patient electrocardiographic data were classified as either survivals or cardiac deaths. SVM models were established based on different combinations of heart-rate dynamic variables and compared to left ventricular ejection fraction (LVEF), standard deviation of normal-to-normal intervals (SDNN) and deceleration capacity (DC) of heart rate. We tested the accuracy of predictors by assessing the area under the receiver-operator characteristics curve (AUC). RESULTS: We evaluated a SVM algorithm that integrated various electrocardiographic features based on three models: (A) HRV complex; (B) 6 dimension vector; and (C) 8 dimension vector. Mean AUC of HRV complex was 0.8902, 0.8880 for 6 dimension vector and 0.8579 for 8 dimension vector, compared with 0.7424 for LVEF, 0.7932 for SDNN and 0.7399 for DC. CONCLUSIONS: HRV complex yielded the largest AUC and is the best classifier for predicting cardiac death after AMI.


Assuntos
Técnicas de Apoio para a Decisão , Eletrocardiografia Ambulatorial , Frequência Cardíaca , Infarto do Miocárdio/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Fatores de Risco , Volume Sistólico , Máquina de Vetores de Suporte , Fatores de Tempo , Função Ventricular Esquerda
12.
J Phys Condens Matter ; 26(8): 085301, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24501192

RESUMO

Using the Landauer-Büttiker formula, we study the effect of dephasing on the transport properties of the HgTe/CdTe p-n junction. It is found that in the HgTe/CdTe p-n junction the topologically protected gapless helical edge states manifest a quantized 2e²/h plateau robust against dephasing, in sharp contrast to the case for the normal HgTe/CdTe quantum well. This robustness of the transport properties of the edge states against dephasing should be attributed to the special construction of the HgTe/CdTe p-n junction, which limits the gapless helical edge states to a very narrow region and thus weakens the influence of the dephasing on the gapless edge states to a large extent. Our results demonstrate that the p-n junction could be a substitute device for use in experimentally observing the robust edge states and quantized plateau. Finally, we present a feasible scheme based on current experimental methods.

13.
J Ultrasound Med ; 33(1): 83-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24371102

RESUMO

OBJECTIVES: We investigated whether transesophageal echocardiography (TEE) assisted with a computer-aided diagnostic (CAD) algorithm was superior to TEE in diagnosing left atrial (LA)/left atrial appendage (LAA) thrombi in patients with atrial fibrillation (AF) in a single prospective study. METHODS: Transesophageal echocardiography was performed in patients with AF, and images were reconstructed. Gray level co-occurrence matrix-based features were calculated and then classified using an artificial neural network. The original data and processed images by the CAD system were studied by 5 radiologists independently in a blind manner. The diagnostic performance of each radiologist was evaluated. RESULTS: One hundred thirty patients with AF were investigated. Thirty-one patients (23.9%) had a diagnosis of LA/LAA thrombi. The mean sensitivity ± SD of TEE for LA/LAA thrombi was 0.933 ± 0.027, which was noticeably improved by CAD (0.955 ± 0.021; P < .05). The specificity of TEE was 0.811 ± 0.055, which was markedly lower than that by TEE plus CAD (0.970 ± 0.009; P < .05). The positive predictive value of TEE was low (0.613 ± 0.073) compared to that of TEE plus CAD (0.908 ± 0.027; P < .001), whereas the negative predictive values were comparable for TEE, CAD, and TEE plus CAD. Diagnosis of an LA/LAA thrombus by TEE plus CAD had a higher accuracy rate (0.966 ± 0.011) than that by TEE (0.840 ± 0.047; P < .01). The mean area under the receiver operating characteristic curve (Az) for TEE was 0.834 ± 0.009 (95% confidence interval [CI], 0.815-0.852), which was markedly lower than the Az for TEE plus CAD (0.932 ± 0.005; 95% CI, 0.921-0.943). The use of CAD significantly improved the Az values for all 5 radiologists (P < .001). CONCLUSIONS: The CAD algorithm significantly improves the diagnostic accuracy of TEE for LA/LAA thrombi in patients with AF.


Assuntos
Algoritmos , Fibrilação Atrial/diagnóstico por imagem , Ecocardiografia Transesofagiana/métodos , Átrios do Coração/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Trombose/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Trombose/etiologia
14.
Fitoterapia ; 92: 61-71, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24125915

RESUMO

Eubacterium limosum ZL-II is an anaerobic bacterium with demethylated activity, which was isolated from human intestinal bacteria in our previous work. In this study, the flavonolignan constituents of Silybi Fructus were biotransformed by E. limosum(1) ZL-II, producing four new transformation products - demethylisosilybin B (T1), demethylisosilybin A (T2), demethylsilybin B (T3) and demethylsilybin A (T4), among which T1 and T2 were new compounds. Their chemical structures were identified by ESI-TOF/MS, (1)H NMR, (13)C NMR, HMBC and CD spectroscopic data. The bioassay results showed that the transformation products T1-T4 exhibited significant inhibitory activities on Alzheimer's amyloid-ß 42 (Aß42(2)) aggregation with IC50 values at 7.49 µM-10.46 µM, which were comparable with that of the positive control (epigallocatechin gallate, EGCG(3), at 9.01 µM) and much lower than those of their parent compounds (at not less than 145.10 µM). The method of biotransformation by E. limosum ZL-II explored a way to develop the new and active lead compounds in Alzheimer's disease from Silybi Fructus. However, the transformation products T1-T4 exhibited decreased inhibitory activities against human tumor cell lines comparing with their parent compounds.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Eubacterium/metabolismo , Flavonolignanos/farmacologia , Intestinos/microbiologia , Fragmentos de Peptídeos/antagonistas & inibidores , Extratos Vegetais/farmacologia , Silybum marianum/química , Doença de Alzheimer/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Biotransformação , Flavonolignanos/química , Flavonolignanos/metabolismo , Frutas , Células HeLa , Humanos , Mucosa Intestinal/metabolismo , Silybum marianum/microbiologia , Estrutura Molecular , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/metabolismo
15.
Yao Xue Xue Bao ; 47(11): 1440-6, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387074

RESUMO

Tyrosinase is a key enzyme related to skin pigmentation disorders of elderly people, while self-aggregation of the amyloid-beta peptide, Abeta42, has been considered as a key event in the pathogenesis of Alzheimer's disease (AD). The present study was undertaken to investigate the inhibitory effects of 20 samples from Rhodiola species on tyrosinase and Abeta42 aggregation, and to isolate their corresponding bioactive components. The results demonstrated that the oligomeric proanthocyanidins (OPCs) commonly found in Rhodiola species were the major bioactive components corresponding to their anti-tyrosinase and anti-Abeta42 aggregation bioactivities. Salidroside, a representative compound of Rhodiola plants, proved not to be active in the present studies.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Monofenol Mono-Oxigenase/metabolismo , Fragmentos de Peptídeos/metabolismo , Proantocianidinas/farmacologia , Rhodiola/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Medicamentos de Ervas Chinesas/isolamento & purificação , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fragmentos de Peptídeos/antagonistas & inibidores , Fenóis/isolamento & purificação , Fenóis/farmacologia , Raízes de Plantas/química , Plantas Medicinais/química , Proantocianidinas/isolamento & purificação
16.
J Phys Condens Matter ; 23(38): 385302, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21891851

RESUMO

We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device.

17.
J Phys Condens Matter ; 22(31): 315304, 2010 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21399360

RESUMO

We study the band and transport features of zigzag graphene nanoribbon with an antidot lattice. It is found that an antidot lattice could turn semi-metal graphene into a semiconductor. The size of the band gap can be tuned by the position of the antidots and the distance D between the two nearest antidots. For a finite superlattice with N antidots and a large D, a group of (N - 1) splitting resonant peaks and transmission-blockade regions appear alternately in the conductance spectrum. This indicates the formation of minibands and minigaps. In addition, Fano resonances can be observed when the antidots are localized near one edge of the nanoribbon. These features provide potential applications for graphene-based electronic and optoelectronic devices.

18.
Planta Med ; 75(15): 1613-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19591091

RESUMO

Salvia species have an extensive distribution and a long history of medical use in China. In this study, chemical differences between different Salvia species were thoroughly investigated, and 86 constituents were characterized through a sensitive HPLC-DAD-ESI-MS (n) method. In total, 19 Salvia species were screened. Our study suggested that Ser. Brachylomae, Ser. Digitaloidites, Ser. Castaneae, and Ser. Miltiorrhizae were the sibling series (Ser. is short for series) and that Ser. Brachylomae, Ser. Maximowicziana, and Ser. Campanulatae were unique with regard to their constituents in addition to having componential affinity. This study offered a simple chemotaxonomy approach and a reasonable bioactivity interpretation of Salvia species.


Assuntos
Medicamentos de Ervas Chinesas/química , Salvia/química , Salvia/classificação , China , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Especificidade da Espécie
19.
Yao Xue Xue Bao ; 44(4): 440-2, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19545066

RESUMO

An in vitro screening model was applied to test the inhibitory activities of 17 Salvia species on protein tyrosine phosphatase 1B (PTP1B). Root methanol extracts from wild-collected Salvia species were analyzed using this model. Most of the samples tested showed positive activities on human PTP1B. The inhibition rates of Salvia crude extracts varied from 9.76% to 100% at 30 microg x mL(-1), with the most convincing effects coming from Salvia evansiana and Salvia castanea. HPLC analysis revealed seven components shared by Salvia samples could be related to the inhibitory activities.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Salvia/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Humanos , Raízes de Plantas/química , Plantas Medicinais/química , Salvia/classificação
20.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 23(12): 1163-6, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18062891

RESUMO

AIM: To construct the prophylactic recombinant HPV58-attenuated Shigella vector live vaccine and evaluate its protective efficacy and immunogenicity in the Guinea pig Keratoconjunctivitis model. METHODS: The HPV58 L1 gene was cloned into PUCMT, and the recombinant plasmid HPV58 L1-pCVD442 was constructed and introduced into attenuated Shigella (Sf301: deltavirG) with helper plasmid PRK2013 by filter mating. After homologous recombination, the positive colonies in Sf301: deltavirG strains contained HPV58L1 gene were selected and verified by PCR. The expressed HPV58L1 protein was harvested and analyzed by SDS-PAGE and Western blot. The bio-activity of the interested protein was identified by mouse erythrocyte hemagglutination assay, and the VLP formation was proved with transmission electron microscope. Guinea pig Keratoconjunctivitis model was used to evaluate protective efficacy and immunogenicity of the vaccine. 20 days after immunization, serum HPV58L1-IgG, IgA level and serum sf301 LPS- IgG, IgA level were measured by ELISA, and HPV58 L1-specific IgA-ASC and IgG-ASC of spleen and lymph nodes (SVCLN, MDLN, MSLN and pp) were measured by ELISPOT assay. RESULTS: HPV58 L1 protein with MW 60 kDa was confirmed by Western blot. The ability of the interested protein to self-assemble into VLPs was identified by transmission electron microscope, and the result of murine erythrocyte hemagglutination assay indicated that the given proteins expressed by the recombinant bacillus had similar characteristics as the natural HPV58L1 protein.In the Guinea pig Keratoconjunctivitis Model, animal immune results showed that there were no Keratoconjunctivitis occurred in the immune group(HPV58-attenuated Shigella), and after Sf301 attacking, 80% eyes had no Keratoconjunctivitis occurrence. 20 days after immunization, serum HPV58L1-IgG, IgA level were obviously increased; but serum sf301 LPS-IgG position was just slightly increased; ELISPOT results showed that HPV58 L1-specific IgA-ASC and IgG-ASC of spleen and lymph nodes were also obviously increased. CONCLUSION: Recombinant HPV58L1-attenuated Shigella vector live vaccine could induce strong humoral immune responses in the immunized animals.


Assuntos
Alphapapillomavirus/genética , Vacinas Bacterianas/imunologia , DNA Recombinante/genética , Vetores Genéticos/genética , Fenômenos Imunogenéticos , Ceratoconjuntivite/imunologia , Shigella/imunologia , Alphapapillomavirus/ultraestrutura , Animais , Anticorpos/sangue , Anticorpos/imunologia , Western Blotting , Proteínas do Capsídeo/imunologia , Clonagem Molecular , Cobaias , Hemaglutinação , Mesotelina , Camundongos , Microscopia Eletrônica , Vacinas Atenuadas/imunologia
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