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1.
Curr Med Sci ; 39(6): 863-873, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31845216

RESUMO

Voltage-gated sodium (Nav) channels are critical players in the generation and propagation of action potentials by triggering membrane depolarization. Mutations in Nav channels are associated with a variety of channelopathies, which makes them relevant targets for pharmaceutical intervention. So far, the cryoelectron microscopic structure of the human Nav1.2, Nav1.4, and Nav1.7 has been reported, which sheds light on the molecular basis of functional mechanism of Nav channels and provides a path toward structure-based drug discovery. In this review, we focus on the recent advances in the structure, molecular mechanism and modulation of Nav channels, and state updated sodium channel blockers for the treatment of pathophysiology disorders and briefly discuss where the blockers may be developed in the future.

2.
Mikrochim Acta ; 186(11): 732, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667627

RESUMO

The authors describe an electrochemical and an optical method for the determination of As(V) by using iron oxyhydroxide (FeOOH) nanorods that display peroxidase-mimicking activity. The nanorods catalyze the oxidation of substrate ABTS by H2O2 to form a green product with an absorption maximum at 418 nm. If, however, As(V) is electrostatically adsorbed on the nanorods, the oxidation is gradually inhibited. A colorimetric assay was worked out based on these findings. Response is linear in the 0 to 8 ppb and 8 to 200 ppb As(V) concentration range, and the detection limit is 0.1 ppb. Even higher sensitivity is achieved in an electrochemical method which is based on the excellent electrical conductivity of FeOOH nanorods. Electrochemical analysis of As(V) was achieved by first adsorbing As(V) on the nanorods. This inhibits the ABTS reduction current signal, best measured at a potential of 150 mV (vs. Ag/AgCl). The linear range extends from 0.04 to 200 ppb, and the detection limit is as low as 12 ppt. Graphical abstract Schematic representation of FeOOH nanorod-based colorimetric and electrochemical assays for arsenate (As(V)). As(V) adsorbed on FeOOH nanorods inhibits the peroxidase-mimicking activity of nanorods, and a colorimetric and electrochemical dual-signal assay was constructed to achieve sensitive determination of As(V).

3.
Mikrochim Acta ; 186(8): 594, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31372831

RESUMO

A method is described for the colorimetric determination of the activity of CpG methyltransferase (M.SssI). It is based on (a) the crosslinking effect between dsDNA-modified gold nanoparticles (AuNPs) and graphene oxide (GO), and (b) an amplification reaction with the aid of a nicking enzyme. To avoid the aggregation of AuNPs (which would produce false signals), a hairpin DNA was connected to the AuNPs. Thus, the red color of the solution (measured at 530 nm) increases linearly with the activity of M.SssI from 0.2 to 60 U·mL-1, and the limit of detection is 67 U·mL-1. This is superior to some reported strategies. The method was successfully applied to analyze spiked serum samples. Conceivably, it represents a powerful tool for use in drug development and diagnosis. Graphical abstracts A method based on the conjugated cross-linking effect between dsDNA modified Au NPs and GO coupled with an amplification reaction of nicking enzyme has been developed for colorimetric detection of the activity of CpG methyltransferase (M.SssI).

4.
Mikrochim Acta ; 186(4): 241, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30868262

RESUMO

The activity of terminal deoxynucleotidyl transferase (TdTase) is a biomarker for routine diagnosis of acute leukemia. A method has been developed for the determination of TdTase activity. It is based on the use of silver nanoclusters (AgNCs) whose yellow fluorescence is enhanced by an in-situ grown DNA tail of TdTase-polymerized and guanine-rich DNA at the 3' end of a hairpin DNA. The fluorescence, best measured at excitation/emission peaks of 530/585 nm, increases linearly in the 1 to 35 mU mL-1 TdTase activity range. The detection limit is 0.8 mU mL-1. The method is cost-efficient, selective and convenient. It integrates enhancement of the fluorescence of AgNCs and target recognition into a single process. Graphical abstract Schematic presentation of a method for determination of TdTase activity. It is based on AgNCs fluorescence enhanced by in-situ grown TdTase-polymerized G-rich DNA tail. The method integrates AgNCs fluorescence enhancement and the target recognition into a single process.


Assuntos
DNA Nucleotidilexotransferase/sangue , DNA/química , Ensaios Enzimáticos/métodos , Nanopartículas Metálicas/química , Sequência de Bases , Biomarcadores/sangue , Técnicas Biossensoriais/métodos , DNA/genética , Fluorescência , Humanos , Sequências Repetidas Invertidas , Leucemia/diagnóstico , Limite de Detecção , Prata/química , Espectrometria de Fluorescência/métodos
5.
Chem Biol Interact ; 297: 119-129, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30365938

RESUMO

Diabetes-associated sexual dysfunction and fertility impairments are major secondary complications in diabetic patients and animal models. Natural herbs are important sources of therapeutic agents for diabetic complications. This study investigated the effect of vitexin on male sexual dysfunction and fertility impairments in streptozotocin (STZ)-induced diabetic mice. Diabetes was induced by intraperitoneal injection of 45 mg/kg STZ for 5 consecutive days in mice. Vitexin (10, 20 or 40 mg/kg) and Sildenafil citrate (SC, 5 mg/kg) were administered daily for 62 days after the induction of diabetes. The parameters of sexual behavior and fertility were analyzed. The reproductive organ weight, sperm motility, and viability of the treated mice were examined. Testicular histopathological alterations were detected by hematoxylin and eosin (H&E) staining. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate serum hormonal levels. Results showed that 40 mg/kg vitexin significantly improved the sexual behavior and fertility levels compared with the diabetic group. Moreover, vitexin (20 or 40 mg/kg) significantly increased reproductive organ weight and improved testicular pathological structure damage. Meanwhile, sperm analysis demonstrated that vitexin significantly restored sperm quality in a dose-dependent manner. Furthermore, ELISA data showed that vitexin significantly increased the serum testosterone (T), follicular-stimulating hormone (FSH), and luteinizing hormone (LH) levels but decreased the gonadotropin-releasing hormone (GnRH) level to different degrees. These findings suggest that vitexin ameliorates sexual dysfunction and fertility impairments in male diabetic mice possibly by modulating the hypothalamus-pituitary-gonadal axis.


Assuntos
Apigenina/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Fertilidade/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Animais , Apigenina/administração & dosagem , Apigenina/química , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Injeções Intraperitoneais , Masculino , Camundongos , Estrutura Molecular , Disfunções Sexuais Fisiológicas/induzido quimicamente , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Estreptozocina/administração & dosagem , Relação Estrutura-Atividade
6.
Anal Sci ; 34(8): 959-964, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30101892

RESUMO

DNA methyltransferase (MTase) is related to transcriptional repressor activity in biological functions. It is an essential for cancer diagnosis and therapeutics to detect DNA MTase activity sensitively. Here, a fluorescent system based on polymerase amplification has been developed to detect DNA adenine MTase (Dam) activity sensitively. The amplification is triggered by the probe DNA regions a, which are the primes of a polymerase-induced replicated reaction. They come from methylation and a digestion reaction of DNA S1-S1, including a 5'-GATC-3' sequence recognized by Dam MTase and methylation sensitive restriction endonuclease Dpn I. The intensities of fluorescence are dependent on the Dam MTase activity. The method shows fine sensitivity with a detection limit of 3.2 × 10-4 U mL-1 and specificity for Dam MTase. In human serum samples, the method has been successfully applied, and it has also been used to screen the inhibitors, which means that the developed method can be a powerful and potential tool for drug development and clinical diagnosis in the future.


Assuntos
Técnicas Biossensoriais , Ensaios Enzimáticos/métodos , Fluorescência , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA Metiltransferases Sítio Específica (Adenina-Específica)/análise , DNA Metiltransferases Sítio Específica (Adenina-Específica)/metabolismo , Sondas de DNA/química , Sondas de DNA/metabolismo , Humanos , Espectrometria de Fluorescência
7.
Cell Tissue Res ; 374(3): 653-666, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30073544

RESUMO

Testicular dysfunction is one of the serious secondary complications in diabetes. Lycium barbarum polysaccharide (LBP) has long been considered to possess a wide range of beneficial properties including antiaging, anticancer and reproductive-enhancing. Abnormal autophagy was reported to play a significant role in accelerating diabetic reproductive injury. However, the autophagy regulation mechanism of LBP on diabetic testicular dysfunction is incompletely understood. We investigate the protective effects of LBP on diabetic testicular dysfunction and its underlying mechanism with different approaches. Protective effects of LBP (40 mg/kg) on testicular functions were assessed through the use of sperm parameters, testosterone levels and hematoxylin and eosin staining. Antioxidant capacity and serum malondialdehyde levels were determined using assay kits. Immune intensity of Beclin-1 and LC3I in testes was detected by immunofluorescence staining. Western blot analysis was used to detect expressions of p-PI3K, Akt, p-Akt, Beclin-1, LC3I and LC3II proteins. Q-PCR was used to evaluate Beclin-1 and LC3I mRNA expressions in testis. Administration of LBP (40 mg/kg) considerably recovered testicular function, obviously improved testicular histopathologic structure and significantly increased antioxidant enzyme activities. Immunofluorescence staining showed that immune intensity of Beclin-1 and LC3I significantly decreased in the LBP 40 mg/kg group. The results of Q-PCR and western blot analysis showed that LBP 40 mg/kg significantly downregulated Beclin-1 and LC3I protein expressions upregulated p-PI3K and p-Akt protein expressions and decreased Beclin-1 and LC3I mRNA expressions compared with diabetic mice. In conclusion, inhibition of PI3K/Akt pathway-mediated testicular excessive autophagy may be a target for protective effects of LBP on diabetic testicular dysfunction.


Assuntos
Autofagia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Testículo/patologia , Testículo/fisiopatologia , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagossomos/ultraestrutura , Autofagia/efeitos dos fármacos , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteína Beclina-1/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Camundongos Endogâmicos ICR , Proteínas Associadas aos Microtúbulos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testosterona/sangue
8.
Blood ; 132(11): 1146-1158, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30054295

RESUMO

Mature T-cell lymphomas, including peripheral T-cell lymphoma (PTCL) and extranodal NK/T-cell lymphoma (NKTL), represent a heterogeneous group of non-Hodgkin lymphomas with dismal outcomes and limited treatment options. To determine the extent of involvement of the JAK/STAT pathway in this malignancy, we performed targeted capture sequencing of 188 genes in this pathway in 171 PTCL and NKTL cases. A total of 272 nonsynonymous somatic mutations in 101 genes were identified in 73% of the samples, including 258 single-nucleotide variants and 14 insertions or deletions. Recurrent mutations were most frequently located in STAT3 and TP53 (15%), followed by JAK3 and JAK1 (6%) and SOCS1 (4%). A high prevalence of STAT3 mutation (21%) was observed specifically in NKTL. Novel STAT3 mutations (p.D427H, E616G, p.E616K, and p.E696K) were shown to increase STAT3 phosphorylation and transcriptional activity of STAT3 in the absence of cytokine, in which p.E616K induced programmed cell death-ligand 1 (PD-L1) expression by robust binding of activated STAT3 to the PD-L1 gene promoter. Consistent with these findings, PD-L1 was overexpressed in NKTL cell lines harboring hotspot STAT3 mutations, and similar findings were observed by the overexpression of p.E616K and p.E616G in the STAT3 wild-type NKTL cell line. Conversely, STAT3 silencing and inhibition decreased PD-L1 expression in STAT3 mutant NKTL cell lines. In NKTL tumors, STAT3 activation correlated significantly with PD-L1 expression. We demonstrated that STAT3 activation confers high PD-L1 expression, which may promote tumor immune evasion. The combination of PD-1/PD-L1 antibodies and STAT3 inhibitors might be a promising therapeutic approach for NKTL, and possibly PTCL.


Assuntos
Antígeno B7-H1/biossíntese , Regulação Neoplásica da Expressão Gênica , Mutação de Sentido Incorreto , Proteínas de Neoplasias/biossíntese , Fator de Transcrição STAT3/biossíntese , Transdução de Sinais , Substituição de Aminoácidos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Humanos , Linfoma Extranodal de Células T-NK , Proteínas de Neoplasias/genética , Fator de Transcrição STAT3/genética
9.
Mikrochim Acta ; 185(5): 280, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29725866

RESUMO

A method is reported for the fluorometric quantitation of microRNA. It is making use of a luminescent probe deribed from terbium(III) ion whose fluorescence is sensitized with a guanine-rich (G-rich) nucleotide. The probe has a large Stokes' shift and strong and sharp emission bands. The assay relies on the wide substrate specificity of terminal deoxynucleotidyl transferase (TdTase), which catalyzes the formation of long G-rich nucleotides when using microRNA primer as a trigger to start the polymerization. The addition of Tb(III) induces the formation of a G-quadruplex from the G-rich nucleotide, and this strongly enhances the green fluorescence of Tb(III) (peaking at 545 nm upon photoexcitation at 290 nm). Specifically, microRNA-21 was chosen as the analyte. The fluorescence intensity of Tb(III) increases linearly in the 1 pM to 1 nM microRNA concentration range, and the detection limit is as low as 0.11 pM. The method can distinguish between family members of microRNA and performs excellently even when applied to extracts of cancer cells. Graphical abstract A fluorometric technique is reported for the determination of microRNA. It is based on signal enhancement based on the sensitization of terbium(III) via a guanine-rich nucleotide sequence. Klenow Fragment exo- (KFexo-) generates DNA sequence at the 3'-OH of microRNA, and terminal deoxynucleotidyl transferase (TdTase) catalyzes the formation of long G-rich nucleotides.


Assuntos
Técnicas Biossensoriais/métodos , DNA Nucleotidilexotransferase/metabolismo , Nucleotídeos de Guanina/química , Nucleotídeos de Guanina/metabolismo , Medições Luminescentes/métodos , MicroRNAs/análise , Térbio/química , Células A549 , Humanos , Células MCF-7
10.
Anal Chim Acta ; 1016: 12-18, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-29534800

RESUMO

In this work, a newly developed surface plasma resonance (SPR) system for the sensitive detection of M.SssI activity has been designed based on double signal amplification with DNA chain cyclic reactions and AuNPs. In the absence of M.SssI, hairpin DNA 1 (HP1) can be cleaved into s1 fragments catalyzed by HpaII. The s1 fragments can then trigger a recycling process of hairpin DNA 2 (HP2) hybridization and subsequently release massive s2 and s3 in the solution of Nt.AlwI and HPII. AuNPs-DNA can be captured on gold film by the released s2 and s3 to produce a strong SPR signal. Whereas in the presence of M.SssI, methylated HP1 cannot be cleaved by HpaII, thus produce a weak SPR signal. The SPR signals are dependent on the M.SssI concentration in the range from 0.5 to 50 U/mL. The successful detection of M.SssI activity in clinical serum samples and inhibition of M.SssI using 5-Aza and 5-Aza-dC indicate a great potential of this strategy for building new monitoring platform in bioanalysis and clinical biomedicine.


Assuntos
Metiltransferases/sangue , Ressonância de Plasmônio de Superfície , Técnicas Eletroquímicas , Ouro/química , Humanos , Metiltransferases/metabolismo , Propriedades de Superfície
11.
Biosens Bioelectron ; 102: 211-216, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29145074

RESUMO

We propose a ratiometric electrochemical assay for detecting microRNA (miRNA) on the basis of dual-amplification mechanism by using distinguishable electrochemical signals from thionine (Thi) and ferrocene (Fc). The thiol-modified and ferrocene-labeled hairpin capture probes (CP) are first immobilized on an Au electrode via Au-S reaction. The target miRNA hybridizes with CP and unfolding the hairpin structure of CP to form miRNA-DNA duplexes. Then, kamchatka crab duplex specific nuclease (DSN) specifically cleaves the DNA in miRNA-DNA duplexes, leading to the release of miRNA and another cleaves cycle, meanwhile, numerous Fc leaves away from the electrode surface and leads to the signal-off of Fc. The residual fragment on electrode surface acts as a HCR primer to form dsDNA polymers through in situ HCR with the presence of the primer and two probes (HDNA and HDNA'), resulting in the capture of numerous DNA/Au NPs/Thi and the signal-on of Thi. The dual-amplification mechanism significantly amplifies the decrease of Fc signal and the increase of Thi signal for ratiometric readout (IThi/IFc), thus providing a sensitive method for the selective detection of miR-141 with a detection limit down to 11aM. The dual-signal ratiometric outputs have an intrinsic self-calibration to the effects from system, which is promising to be applied in biosensing and clinical diagnosis.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , MicroRNAs/isolamento & purificação , Compostos Ferrosos/química , Ouro/química , Humanos , Limite de Detecção , Metalocenos/química , MicroRNAs/química , Hibridização de Ácido Nucleico , Fenotiazinas/química
12.
Biomed Pharmacother ; 90: 562-574, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28407577

RESUMO

Diabetes mellitus (DM) is a major health problem that affects patients' quality of life quality throughout the world due to its many complications. Reproductive dysfunction is one of the major secondary complications in both diabetic animals and human beings. Furthermore, DM has recently broken the age barrier and has been heavily diagnosed in children and young persons of reproductive age. In the past few years, many studies on DM in male reproductive functions in both diabetic men and experimental diabetic animals have been published. It is recognized that sustained hyperglycemia, which impairs reproductive function in diabetic men, is at risk of developing. DM harmfully affects male reproductive functions in multiple areas; these may include spermatogenesis, sperm maturation, fertility capability, penile erection, and ejaculation. Traditional medicine and folklore worldwide have used numerous medicinal plants to manage the diabetic reproductive dysfunction because bioactive phyto-constituents are affluent in many places. Unfortunately, the exact reasons for diabetic male reproductive dysfunction are not completely understood and currently there are no treatments in reproductive medicine specifically for such lesions. The aim of this review is to summarize current research findings of DM on reproductive functions, to elaborate the underlying mechanisms related to these diseases via in vivo and in vitro studies, and to describe the ameliorative effects of medicinal plants or their products. The review findings provide a systematic understanding of DM on the reproductive functions and lay the theoretical foundation for developing the direction of reproductive medicine.


Assuntos
Complicações do Diabetes/etiologia , Complicações do Diabetes/fisiopatologia , Diabetes Mellitus/fisiopatologia , Genitália Masculina/fisiopatologia , Animais , Humanos , Masculino
13.
Trials ; 16: 371, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26292720

RESUMO

BACKGROUND: Recently, clinical observations reported the potential benefit of vagus nerve stimulation (VNS) for pediatric epilepsy. Transcutaneous auricular vagus nerve stimulation (ta-VNS) is a newer non-invasive VNS, making it more accessible for treating pediatric epilepsy, yet there is limited clinical evidence for its effectiveness. METHODS/DESIGN: A three-center, randomized, parallel, controlled trial will be carried out to evaluate whether ta-VNS improves pediatric epilepsy. Pediatric patients aged 2 to 14 years with epilepsy will be recruited and randomly assigned to transcutaneous auricular vagus nerve stimulation (ta-VNS) group, transcutaneous auricular non-vagus nerve stimulation (tan-VNS) group, and control group with a 1:1: sqrt(2) allocation, as per a computer generated randomization schedule stratified by study center using permuted blocks of random sizes. We will use Zelen's design, in which randomization occurs before informed consent. Patients in the stimulation groups will receive tan-VNS or ta-VNS three times a day for 6 months. Patients in the control group will not be provided with any stimulation during the 6 months. The guardians of the patients are required to keep a detailed diary to record the data. Outcome assessment including seizure frequency, electroencephalogram (EEG), heart rate variability (HRV) analysis, quality of life (QOL) and adverse events will be made at baseline and 2, 4 and 6 months after ta-VNS initiation. The seizure frequency and adverse events will be followed up at 1 year and 1.5 years after ta-VNS initiation. DISCUSSION: Results of this trial will help clarify whether ta-VNS treatment is beneficial for pediatric patients, and will make clear whether the anticonvulsive effect of ta-VNS is correlated with the improvement of sympathovagal imbalance. CLINICAL TRIALS IDENTIFIER: NCT02004340 . Registration date: 13 November 2013.


Assuntos
Encéfalo/fisiopatologia , Orelha/inervação , Epilepsia/terapia , Estimulação do Nervo Vago/métodos , Adolescente , Fatores Etários , Ondas Encefálicas , Criança , Pré-Escolar , China , Protocolos Clínicos , Eletroencefalografia , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Qualidade de Vida , Projetos de Pesquisa , Fatores de Tempo , Resultado do Tratamento , Estimulação do Nervo Vago/efeitos adversos
14.
Biosens Bioelectron ; 68: 668-674, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25660511

RESUMO

Herein, a sensitive and selective sensor for biothiols based on colorimetric assay is reported. S-adenosyl-L-methionine (SAM) could induce the selective aggregation of unmodified gold nanoparticles (AuNPs) by electrostatic interaction. In the presence of biothiols, such as glutathione (GSH), homocysteine (Hcy), and cysteine (Cys), AuNPs prefer to react with thiols of biothiols rather than SAM due to the formation of Au-S bond. Thus, the AuNPs turn from the aggregation to the dispersion state, and the corresponding color variation in the process of anti-aggregation of AuNPs can be used for the quantitative screening of biothiols through UV-vis spectroscopy or by the naked eye. Under optimized conditions, a good linear relationship in the range of 0.4-1.2 µM is obtained for Cys, 0.2-0.9 µM for GSH, and 0.6-3.0 µM for Hcys. The detection limits of this assay for GSH, Cys and Hcys are 35.8 nM, 21.7 nM, and 62.4 nM, respectively. This colorimetric assay exhibits rapid operation (within 5 min), high selectivity and sensitivity towards biothiols with tunable dynamic ranges.


Assuntos
Técnicas Biossensoriais , Cisteína/isolamento & purificação , Glutationa/isolamento & purificação , Homocisteína/isolamento & purificação , Colorimetria , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Metionina/análogos & derivados , Metionina/química
15.
Artigo em Chinês | MEDLINE | ID: mdl-22883582

RESUMO

OBJECTIVE: To establish a model of ototoxicity in guinea pigs with acoustically evoked short latency negative response (ASNR) and verify the responsible organ of ASNR based on microscopic characteristics of basal membranes, saccules, utricles and ampulla canalis semicircularis of the inner ear. METHODS: Total of 45 guinea pigs were employed in the experiment, which were randomly divided into the control group (15 subjects, 30 ears) and the deafened group (30 subjects, 60 ears). Each animal experienced auditory brainstem response (ABR). A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were performed ABR test from 7 to 10 days after the drug administration. The deafened group was further divided into ASNR group and non-ASNR group based on the presence of ASNR. All the guinea pigs were sacrificed after ABR tests. The Corti organ, macula sacculi, macula utriculi and crista ampullaris were observed by light microscope. RESULTS: In the deafened group (60 ears), 3 subjects died postoperatively, 27 subjects (54 ears) provided full data. ASNR was elicited in 19 ears (35.2%, 19/54), the thresholds of ASNR were from 110 to 125 dBSPL with average of (121.7 ± 4.5) dBSPL. ASNR latency ranges were 1.80 - 2.08 ms, the average latency of thresholds were (1.93 ± 0.07) ms. The stretched preparation results: overall hair-cell density of macula saccule, macula utriculi and crista ampullaris decreased in order of normal control group, ASNR group and non-ASNR group. There was no difference between the normal group and ASNR group for cell density of macula saccule. Apart from this, statistical differences were found among other groups. CONCLUSIONS: The present study evoked ASNR in an ototoxicity guinea pig model which was profound hearing loss with normal saccular function and normal saccular hair cell density. It suggested that ASNR originates from the saccule and have no relation with cochlear, utricle and semicircular canal according to morphological study.


Assuntos
Estimulação Acústica , Surdez/fisiopatologia , Orelha Interna/fisiopatologia , Potenciais Evocados Auditivos , Animais , Potenciais Evocados Auditivos do Tronco Encefálico , Cobaias , Tempo de Reação , Sáculo e Utrículo/fisiopatologia
16.
Artigo em Chinês | MEDLINE | ID: mdl-21624253

RESUMO

OBJECTIVE: To establish a model of acoustically evoked short latency negative response (ASNR) in guinea pigs, a model of profound hearing loss with normal saccular functions, and verify the correlation between ASNR and vestibular evoked myogenic potential (VEMP). METHODS: Thirty-two healthy guinea pigs were employed in the experiment, which were randomly divided into control group (16 subjects) and deafened group (16 subjects). Each animal experienced auditory and vestibular tests including auditory brainstem response (ABR), VEMP and caloric test. A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by a jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were received ABR, VEMP and caloric test 7 - 10 days following the drug administration. The deafened group was further divided into ASNR group and non-ASNR group, based on the presence of ASNR. RESULTS: In deafened group, five subjects died postoperatively, 11 subjects (22 ears) provided full data, ASNR was elicited in eight ears (36.4%), the threshold was 120 - 130 dB SPL with mean of (124.4 ± 4.96) dB SPL. Its latency range was 1.75 - 2.60 ms with mean of (2.15 ± 0.27) ms. The mean latency of threshold was (2.34 ± 0.18) ms. All eight ASNR ears presented with VEMP. The VEMP threshold, positive and negative potential latencies proved no statistical difference (P > 0.05) between ASNR group and control group. Significant difference was detected between the VEMP presence of ASNR group and non-ASNR group (P = 0.002). There was no statistically significant correlation between VEMP and caloric test neither between ASNR and caloric test in deafened group. CONCLUSIONS: This study evoked ASNR in an ototoxicity guinea pig model which has profound hearing loss with normal saccular functions. The presence of ASNR correlated with VEMP, however, not correlated with caloric test, suggesting that ASNR and VEMP are both originated from the saccule.


Assuntos
Surdez/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico , Potenciais Evocados Auditivos/fisiologia , Sáculo e Utrículo/fisiologia , Potenciais Evocados Miogênicos Vestibulares , Animais , Modelos Animais de Doenças , Cobaias , Testes de Função Vestibular
17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(7): 642-4, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18069549

RESUMO

OBJECTIVE: To assess and explore the quality of life and related factors among 291 outpatient adults with epilepsy. METHODS: From July, 2005 to July, 2006, eligible outpatient epilepsy in a hospital was evaluated by the scale on quality of life in epilepsy-31 (Chinese version). RESULTS: The total scores of quality of life was low (56.46 +/- 16.58). The scores of quality of life in each item were as follows: seizure worry (45.01 +/- 25.25); overall quality of life (56. 12 +/- 16.37); emotional well-being (59.35 +/- 19.56); cognitive function (58.58 +/- 22.41); energy/fatigue (59.12 +/- 18.98); medication effects (40.45 +/- 24.44) and social function (53.00 +/- 26.36). The quality of life of patients with different education background, drug intake and side effects was different significantly (P < 0.05). Data on Multi-linear regression showed that education background, side effects would affect the quality of life. CONCLUSION: The quality of life of outpatient adults with epilepsy was low with education background, while side effects and drugs intake might serve as important factors affecting the quality of life with epilepsy.


Assuntos
Epilepsia/fisiopatologia , Epilepsia/psicologia , Qualidade de Vida , Adulto , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
19.
Zhonghua Yi Xue Za Zhi ; 86(47): 3324-7, 2006 Dec 19.
Artigo em Chinês | MEDLINE | ID: mdl-17313826

RESUMO

OBJECTIVE: To study the sub-classification of temporal lobe epilepsy (TLE) and clinical and etiological characteristics thereof. METHODS: The clinical data of 190 patients with TLE, aged 1.5 approximately 67, were analyzed. The sub-classification was based on clinical manifestations and electroencephalographic recording. The etiology of TLE was mainly concluded from both clinical history and neuroimaging. RESULTS: 172 patients were subclassified as with mesial temporal lobe epilepsy (MTLE), of which 62.2% had auras such as epigastric abnormal sensation and 67.4% had automatism, especially oroalimentary automatism. The electroencephalography recording of the MTLE patients showed interictal epileptic paroxysm discharges over the anterior or mid-anterior temporal areas. The main etiological factors related to MTLE were hippocampal sclerosis, intracranial infection, tumor, cerebrovascular disease, and trauma. Ten patients were subclassified as with lateral temporal lobe epilepsy (LTLE), all presenting auras such as acoust. The electroencephalography recording showed interictal epileptic paroxysm discharges over the posterior or mid-posterior temporal areas. The main etiological factors were trauma, tumor, and atrophy in the LTLE group. Eight patients were unable to be sub-classified. CONCLUSION: Electroencephalography is the main base for classification of TLE. Subclassification of TLE is important in the selection of treatment strategies.


Assuntos
Epilepsia do Lobo Temporal/classificação , Epilepsia do Lobo Temporal/fisiopatologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Eletroencefalografia , Epilepsia do Lobo Temporal/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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