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OBJECTIVE: The aim of this study is to investigate the role of the purinergic P2Y2 receptor in learning and memory processes. MATERIALS AND METHODS: Behavioral, electrophysiological, and biochemical tests of memory function were conducted in P2Y2 receptor knockout (P2Y2R-KO) mice, and the findings were compared to those of wild-type mice with the help of unpaired Student's t-test. RESULTS: The findings of the behavioral Y-maze test showed that the P2Y2R-KO mice had impaired memory and cognitive function. Electrophysiological studies on paired-pulse facilitation showed that glutamate release was higher in the P2Y2R-KO mice than in the WT mice. Furthermore, PCR and Western blot analysis revealed that the mRNA and protein expression of acetylcholinesterase E (AChE) and alpha-7 nicotinic acetylcholine receptors (α7 nAChRs) were increased in the hippocampus of P2Y2R-KO mice. CONCLUSIONS: The findings of this study indicate that P2Y2 receptors are important regulators of both glutamatergic and cholinergic systems in the hippocampus.
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Hipocampo/metabolismo , Trastornos de la Memoria/metabolismo , Receptores Purinérgicos P2Y2/metabolismo , Animales , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Purinérgicos P2Y2/deficienciaRESUMEN
The differential diagnoses of reactive arthritis presenting as arthralgia should be considered as diverse disorders, especially when the symptoms cannot be fully explained by some definite diseases. Do not ignore the indication of bone marrow aspiration. We reported a 50-year-old woman who complained of arthralgia, recurrent fever and rash 9 months ago. Laboratory exams showed mild leukopenia, anemia, thrombocytopenia and increased lymphocyte proportion. She was treated with glucocorticoid after the diagnosis of connective tissue disease was suspected. Until platelet count abruptly decreased to very low level, the final diagnosis of acute lymphoblastic leukemia was made through bone marrow morphology, flow cytometry, and chromosome examination. Therefore, a small number of leukemia is not easily diagnosed by routine operations. Thus when diagnoses are not determined with recurrent symptoms, cautious observation and further examination are required to avoid misdiagnoses or missed diagnoses of acute leukemia.
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Anemia/etiología , Artralgia/etiología , Médula Ósea/patología , Exantema/etiología , Fiebre/etiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Trombocitopenia/etiología , Anemia/fisiopatología , Artralgia/fisiopatología , Recuento de Células Sanguíneas , Examen de la Médula Ósea , Diagnóstico Diferencial , Errores Diagnósticos/prevención & control , Femenino , Humanos , Persona de Mediana Edad , Recuento de Plaquetas , Trombocitopenia/patologíaRESUMEN
Objective: To detect the methylation status of DLC-1 gene in the patients with myelodysplastic syndrome(MDS), the effect of abnormal methylation of DLC-1 gene on the expression of DLC-1 gene, the clinical significance of methylation of DLC-1 gene in MDS patients, and the effect of decitabine on DLC-1 gene expression. Methods: A total of 43 MDS patients were treated in Fujian Medical University Union Hospital from 2013 to 2015. Methylation status of DLC-1 gene in MDS patients were detected by the methylation specific PCR(MSP). The expression of DLC-1 gene mRNA was determined with real-time fluorescence quantitative PCR(RTFQ-PCR). MDS patients were divided into 5 groups (very low-risk, low-risk, intermediate-risk, high-risk and very high-risk, n=0, 8, 7, 18, 10) according to WPSS classification. And the clinical significance of methylation of DLC-1 gene in patients with MDS were investigated. In order to investigate the change in gene methylation and expression of DLC-1 gene after treatment with decitabine, methylation statuses of DLC-1 gene in MDS patients before and after be treated with decitabine were detected by the bisulfite sequencing PCR(BSP). The expressions of DLC-1 gene mRNA of these patients were determined with RTFQ-PCR. Results: Hypermethylation of CpG island of DLC-1 gene was observed in 55.16%(22/43)MDS patients. The expressions of DLC-1 gene mRNA in methylation positive patients were significantly lower than that in methylation negative patients (0.32±0.06 vs 0.91±0.11)(P=0.008). For MDS patients, the DLC-1 methylation rate of intermediate-and high-risk patient was 21/35, which was significantly higher than that of low-risk patient(1/8, P=0.006). The methylation status of DLC-1 gene were monitored in 8 patients before and after treatment with the decitabine (decitabine 20 mg/m(2,) d1-d5/d28, more than 4 courses) , the methylation rate of DLC-1 gene dropped from 57.50%±5.11% to 14.13%±2.07% after treatment(P=0.010). The expression of DLC-1 gene increased after treatment with decitabine(0.67±0.08 vs 0.28±0.06, P=0.015). Conclusions: Methylation of DLC-1 gene is common in MDS patients and may be associated with poor prognosis. Decitabine may activate the expression of DLC-1 gene by demethylation, which may be one of the mechanisms for the treatment of patients with MDS.
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Metilación de ADN , Síndromes Mielodisplásicos , Azacitidina/análogos & derivados , Islas de CpG , Decitabina , Proteínas Activadoras de GTPasa , Expresión Génica , Humanos , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , ARN Mensajero , Proteínas Supresoras de TumorRESUMEN
Tea (Camellia sinensis L.) is a thermophilic evergreen woody plant that has poor cold tolerance. The SAD gene plays a key role in regulating fatty acid synthesis and membrane lipid fluidity in response to temperature change. In this study, full-length SAD cDNA was cloned from tea leaves using rapid amplification of cDNA ends and polymerase chain reaction (PCR)-based methods. Sequence analysis demonstrated that CsSAD had a high similarity to other corresponding cDNAs. At 25°C, the CsSAD transcriptional level was highest in the leaf and lowest in the stem, but there was no obvious difference between the root and stem organs. CsSAD expression was investigated by reverse transcription-PCR, which showed that CsSAD was upregulated at 4° and -5°C. At 25°C, CsSAD was induced by polyethylene glycol, abscisic acid, and wounding, and a similar trend was observed at 4°C, but the mean expression level at 4°C was lower than that at 25°C. Under natural cold acclimation, the 'CsCr05' variety's CsSAD expression level increased before decreasing. The CsSAD expression level in variety 'CsCr06' showed no obvious change at first, but rapidly increased to a maximum when the temperature was very low. Our study demonstrates that CsSAD is upregulated in response to different abiotic conditions, and that it is important to study the stress resistance of the tea plant, particularly in response to low temperature, drought, and wounding.
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Adaptación Fisiológica , Camellia sinensis/enzimología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Estearoil-CoA Desaturasa/genética , Secuencia de Aminoácidos , Camellia sinensis/genética , Camellia sinensis/fisiología , Clonación Molecular , Frío , Sequías , Datos de Secuencia Molecular , Filogenia , Componentes Aéreos de las Plantas/enzimología , Componentes Aéreos de las Plantas/fisiología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raíces de Plantas/enzimología , Raíces de Plantas/fisiología , Alineación de Secuencia , Estearoil-CoA Desaturasa/química , Estearoil-CoA Desaturasa/metabolismoRESUMEN
Recent studies show that mice with selective deletion of the mineralocorticoid receptor (MR) in macrophages are protected from mineralocorticoid-induced cardiac fibrosis and hypertension without altering cardiac macrophage accumulation. However, it is unclear whether preventing macrophages from entering cardiac tissue would provide similar or additional protection in this disease setting. Therefore, we examined mineralocorticoid-induced cardiovascular disease in mice lacking the CCL2 gene (encoding monocyte chemoattractant protein-1), which have a markedly reduced capacity to recruit proinflammatory tissue macrophages. Male wild-type (WT) and CCL2-null mice were treated for 8 days or 8 weeks with either vehicle (control, CON) or deoxycorticosterone (DOC). At both time points, there was a significant reduction in DOC-induced macrophage recruitment (50% at 8 d and 75% at 8 wk) in the heart with a corresponding suppression of cardiac inflammatory markers in the CCL2-null mice. CCL2-null mice given DOC/salt also displayed 35% less cardiac fibrosis at 8 weeks vs WT DOC. Absence of recruited macrophages in CCL2-null mice promotes greater collagen breakdown by matrix metalloproteinase-9 in the heart and also leads to significantly reduced cardiac fibroblast and myofibroblast numbers. Systolic blood pressure (BP) after DOC/salt was significantly lower in CCL2-null than for WT mice. In the aorta at 8 weeks, MR-responsive gene expression remained intact. However, macrophage-mediated proinflammatory gene expression was reduced in the CCL2-null mice and may account for differential regulation of BP. Our data thus demonstrate an important role for CCL2-dependent macrophage recruitment in MR-dependent cardiac inflammation and remodeling and in the regulation of systolic BP.
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Presión Sanguínea , Quimiocina CCL2/metabolismo , Inflamación/metabolismo , Macrófagos/metabolismo , Miocardio/patología , Receptores de Mineralocorticoides/metabolismo , Animales , Quimiocina CCL2/genética , Colágeno/metabolismo , Citocinas/metabolismo , Desoxicorticosterona/metabolismo , Fibroblastos/metabolismo , Fibrosis , Inmunohistoquímica , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Miocardio/metabolismo , Radioinmunoensayo , Factores de TiempoRESUMEN
AIMS/HYPOTHESIS: Pentamethylquercetin (PMQ) has recently been shown to have glucose-lowering properties. Here, we aimed to characterise the effectiveness and underlying mechanisms of PMQ for ameliorating metabolic disorders in vivo and vitro. METHODS: We generated a mouse model of obesity by neonatal administration of monosodium glutamate (MSG) and used it to assess the properties of PMQ as a treatment for metabolic disorders. We also investigated the possible underlying mechanisms of PMQ in the prevention of metabolic disorders. RESULTS: Compared with normal mice, MSG mice had metabolic disorders, including central obesity, hyperinsulinaemia, insulin resistance, hyperglycaemia, hyperlipidaemia, decreased phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), and downregulated levels of GLUT4 in gastrocnemius muscles. In MSG mice, PMQ treatment (5, 10, 20 mg/kg daily) reduced body weight gain, waist circumference, adipose tissue mass, serum glucose, triacylglycerol and total cholesterol, while improving insulin resistance, activating AMPK and increasing ACC phosphorylation and GLUT4 abundance. In C2C12 myotubes, PMQ (10 µmol/l) increased glucose consumption by â¼65%. PMQ treatment (1-10 µmol/l) also activated AMPK, increased ACC phosphorylation and GLUT4 abundance, and upregulated the expression of some key genes involved in fatty acid oxidation. CONCLUSIONS/INTERPRETATION: These findings suggest that PMQ can ameliorate metabolic disorders at least in part via stimulation of AMPK activity.
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Proteínas Quinasas Activadas por AMP/metabolismo , Obesidad/inducido químicamente , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Quercetina/uso terapéutico , Glutamato de Sodio/efectos adversos , Proteínas Quinasas Activadas por AMP/genética , Acetil-CoA Carboxilasa/genética , Acetil-CoA Carboxilasa/metabolismo , Animales , Glucemia/efectos de los fármacos , Western Blotting , Línea Celular , Supervivencia Celular , Colesterol/sangre , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Resistencia a la Insulina , Ratones , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Quercetina/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Triglicéridos , Circunferencia de la Cintura/efectos de los fármacos , Aumento de Peso/efectos de los fármacosRESUMEN
An UPLC-Orbitrap MS system was exploited to develop and validate a method for the simultaneous determination of 11 water-soluble azo dyes (Acid Yellow 17, Acid Red 14, Acid Red 26, Acid Red 73, Acid Orange 52, Acid Orange 7, Acid Orange 12, Acid Yellow 36, Acid Orange 5, Acid Red 88 and Acid Red 9) in soft drinks. Three pairs of isomers and four disulphonated azo dyes were among a total of 11 water-soluble azo dyes obtained and purified using an SPE cartridge. They were well separated using optimized UPLC conditions with a RP18 column and a MS detector with a compatible mobile phase system. All these dyes were detected by the Orbitrap XL mass spectrometer in negative ion mode. HCD tandem MS fragment ions are first reported in this paper, and these fragment ions can be used for identification of isomers of azo dyes. According to SANCO/10684/2009, one quasi-molecular ion in full scan mode as quantification ion and one or two HCD tandem MS fragment ions as identification ions are required for compound confirmation. Matrix-matched calibration was employed for quantification. The linear matrix-matched calibration for the 11 dyes was in the range 5-200 ng g(-1) with correlation coefficients (r) of 0.9939-0.9988. Recoveries were 68.9-110.8% with coefficients of variation of 0.9-12.0%. Depending on the dye and matrix involved, the LODs were between 1.0 and 3.2 ng g(-1) and LOQs were between 5.2 and 9.8 ng g(-1).
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Compuestos Azo/análisis , Bebidas/análisis , Cromatografía Liquida/métodos , Colorantes/análisis , Espectrometría de Masas en Tándem/métodos , Agua/química , Calibración , Límite de Detección , Estándares de Referencia , SolubilidadRESUMEN
One polyclonal antibody against florfenicol and thiamphenicol was produced and a competitive ELISA was developed for the detection of florfenicol and thiamphenicol in swine feed. The ELISA gave a 50% inhibiting concentration of 1.02 ng/mL for florfenicol. For swine feed fortified with 0.05 to 3.0 mg/kg, the interassay recoveries of florfenicol and thiamphenicol ranged from 86.4 to 118.6%, whereas intraassay recoveries of both drug ranged from 90.1 to 126.5% with less than 15% CV. Results obtained from HPLC-tandem mass spectrometry indicated this ELISA procedure could be used as a convenient method for rapid screening of florfenicol and thiamphenicol in swine feed.
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Alimentación Animal/análisis , Antibacterianos/análisis , Ensayo de Inmunoadsorción Enzimática/veterinaria , Porcinos , Tianfenicol/análogos & derivados , Tianfenicol/análisis , Animales , Ensayo de Inmunoadsorción Enzimática/métodosAsunto(s)
Enfermedades de las Glándulas Suprarrenales/diagnóstico , Hemorragia/diagnóstico , Complicaciones del Embarazo/diagnóstico , Trombosis de la Vena/diagnóstico , Enfermedades de las Glándulas Suprarrenales/terapia , Femenino , Hemorragia/terapia , Humanos , Recién Nacido , Masculino , Embarazo , Complicaciones del Embarazo/terapia , Trombosis de la Vena/terapia , Adulto JovenRESUMEN
An analytical method for the simultaneous determination of Sudan dyes (Sudan Red G, Sudan I, Sudan II, Sudan III, Sudan Red 7B and Sudan IV) and Para Red in food by ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) was developed. Samples were extracted with acetonitrile, and water added into the extract. The supernatant was analysed by UPLC-MS/MS after refrigeration and centrifugation. The sample was separated on an Acquity BEH C(18) column, and detected by MS/MS with the multiple reaction monitoring mode. Matrix calibration was used for quantitative testing of the method. The linear matrix calibrations of Sudan dyes and Para Red were 2-50 and 10-250 ng g(-1), respectively, and the regression coefficients were >0.9945. The recoveries were 83.4-112.3% with good coefficients of variation of 2.0-10.8%. The limits of detection were between 0.3 and 1.4 ng g(-1) for the six Sudan dyes, and between 3.7 and 6.0 ng g(-1) for Para Red. The limits of quantification were between 0.9 and 4.8 ng g(-1) for the six Sudan dyes, and between 12.2 and 19.8 ng g(-1) for Para Red.
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Cromatografía Liquida/métodos , Colorantes/análisis , Análisis de los Alimentos , Espectrometría de Masa por Ionización de Electrospray/métodos , Calibración , Límite de Detección , Estándares de Referencia , Reproducibilidad de los ResultadosRESUMEN
The present study aimed to identify, determine the susceptibility, and detect gene cassettes of Arcanobacterium (Actinomyces) pyogenes isolates from cows with endometritis. Arcanobacterium pyogenes isolates were identified first by using the API Coryne Vit system test, and further through PCR. Minimum inhibitory concentrations of 23 antimicrobial agents against A. pyogenes were tested using standard broth microdilution assays according to the protocols of the Clinical and Laboratory Standards Institute. The genes of integrons I and II were amplified by PCR using specific primers. Thirty-two A. pyogenes isolates were isolated from 136 endometritic cows in the Hohhot region. Antibiotic susceptibility tests revealed that all isolates were highly sensitive to fluoroquinolones (100%), macrolides (approximately 81.2 to 100%) and florfenicol (90.6%), aminoglycosides (approximately 15.6 to 81.2%), and tetracyclines (approximately 43.7 to 68.7%). However, 53.1% were resistant to clindamycin, approximately 50 to 65.6% were resistant to penicillins, and approximately 37.5 to 71.9% were resistant to cephalosporins. One hundred percent were resistant to sulfonamides and bacitracin zinc. The integrons were further confirmed by sequencing. No class II integrons were detected, whereas 50% (n = 16) of the A. pyogenes isolates were positive for the presence of the intI I gene, but only 13 contained gene cassettes. Sequence analysis of gene cassettes revealed 6 gene cassettes, 4 of which encode resistant determinants of aminoglycosides (aadA1, aadA5, aadA24, and aadB) and 1 of which encodes the resistance gene of chloramphenicol (cmlA6). The function of the sixth identified cassette, designated ORF1, is unknown. The gene cassette arrays aadA24-ORF1, aadA5, and aadA1-addB-cmlA6 were found in 46.13% (6/13), 38.46% (5/13), and 38.46% (5/13) of the isolates, respectively. These cassettes segregated according to a consistent pattern, with aadA5 always alone, ORF1 always with aadA24, and aadA1-aadB and cmlA6 always together. Most of the positive integrons existed in the multiresistant isolates (n = approximately 3 to 7), indicating that the integrons played an important role in the dissemination and spread of antimicrobial resistance. This is the first report of A. pyogenes infections in dairy cows in China and of detection of gene cassettes and integrons in A. pyogenes.
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Antiinfecciosos/farmacología , Arcanobacterium/efectos de los fármacos , Arcanobacterium/genética , Enfermedades de los Bovinos/microbiología , Endometritis/veterinaria , Integrones/genética , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Bovinos , China , Farmacorresistencia Bacteriana/genética , Endometritis/microbiología , Femenino , Integrasas/genética , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , ARN Ribosómico 16S/genéticaRESUMEN
A study on bioavailability and pharmacokinetics of cefquinome in piglets was conducted after intravenous (i.v.) and intramuscular (i.m.) administrations of 2.0 mg/kg of body weight, respectively. Plasma concentrations were measured by high-performance liquid chromatography assay with UV detector at 268-nm wavelength. Plasma concentration-time data after i.v. administration were best fit by a two-compartment model. The pharmacokinetic values were distribution half-life 0.27 +/- 0.21 h, elimination half-life 1.85 +/- 1.11 h, total body clearance 0.26 +/- 0.08 L/kg.h, area under curve 8.07 +/- 1.91 microg x h/mL and volume of distribution at steady state 0.46 +/- 0.10 L/kg. Plasma concentration-time data after i.m. administration were also best fit by a two-compartment model. The pharmacokinetic parameters were distribution half-life 0.88 +/- 0.42 h, elimination half-life 4.36 +/- 2.35 h, peak concentration 4.01 +/- 0.57 microg/mL and bioavailability 95.13 +/- 9.93%.
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Cefalosporinas/farmacocinética , Animales , Área Bajo la Curva , Disponibilidad Biológica , Cefalosporinas/administración & dosificación , Cefalosporinas/sangre , Cromatografía Líquida de Alta Presión , Femenino , Semivida , Inyecciones Intramusculares , Inyecciones Intravenosas , Masculino , Tasa de Depuración Metabólica , PorcinosRESUMEN
The principal aim of this study was to develop an oral microemulsion formulation of berberine in order to improve its bioavailability. The Microemulsion was prepared with pharmaceutically acceptable ingredients such as oleic acid, Tween 80 and PEG400. Phase diagrams were drawn to elucidate the phase behavior of systems, which were composed of Tween 80 as surfactant and PEG400 as cosurfactant. A single isotropic region, considered to be a bicontinuous microemulsion, was detected in the pseudo ternary phase diagrams. The berberine-loaded microemulsion was characterized by viscosity, refractive index, electrical conductivity and particle size. In vivo pharmacokinetic profile and oral bioavailability were also investigated in rats. The optimized formulation was as follows: 15 wt.% oleic acid, 17 wt.% Tween-80, 17 wt.% PEG400, and 51 wt.% water. The formulated microemulsion was found to be relatively uniform in size (24.0 nm). The in vivo study indicated that the bioavailability of the oral berberine-loaded microemulsion formulation was 6.47 times greater than that of the berberine tablet suspensions. The results suggest that the microemulsion is a promising oral drug delivery system for berberine.
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Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Berberina/administración & dosificación , Berberina/química , Absorción , Administración Oral , Animales , Antiinfecciosos/farmacocinética , Área Bajo la Curva , Berberina/farmacocinética , Disponibilidad Biológica , Fenómenos Químicos , Química Farmacéutica , Química Física , Cromatografía Líquida de Alta Presión , Composición de Medicamentos , Emulsiones , Masculino , Tamaño de la Partícula , Ratas , Ratas Sprague-DawleyRESUMEN
The efficacy of decoquinate against Eimeria infections in broiler chickens was evaluated using two drug sensitive laboratory strains of Eimeria tenella and 20 field isolates of Eimeria spp. collected from farms in China where various anticoccidials (including maduramicin) had been used. Decoquinate (20-40 ppm in feed) and maduramicin (5 ppm) were efficacious against E. tenella laboratory strains, but decoquinate more so than maduramicin. Body weight gains of E. tenella infected chickens were significantly improved, and caecal lesions were prevented, by feeding either decoquinate or maduramicin. Decoquinate also prevented oocyst production, but maduramicin did not. Most (18/20) Eimeria field isolates were resistant to maduramicin, judged by oocyst production; decoquinate at > or =20 ppm completely controlled all 20 field isolates. Decoquinate has potential value as a broiler anticoccidial in China and other countries where it has not been previously used.
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Pollos/parasitología , Decoquinato/farmacología , Eimeria/efectos de los fármacos , Enfermedades de las Aves de Corral/parasitología , Animales , Ciego/patología , China/epidemiología , Coccidiostáticos/farmacología , Relación Dosis-Respuesta a Droga , Resistencia a Medicamentos , Heces/parasitología , Femenino , Lactonas/farmacología , Masculino , Oocistos , Enfermedades de las Aves de Corral/epidemiología , Aumento de PesoRESUMEN
An ELISA was developed for routine screening of ractopamine in swine feeds. Swine feed samples were extracted and purified, and the aqueous portion of the extract was analyzed for ractopamine using ELISA and confirmed by HPLC. For swine complex feeds containing ractopamine at 2.5 to 40 mg/kg, the average recoveries ranged from 73.1 to 86.5% by ELISA and 81.9 to 98.2% by HPLC. For the swine supplement containing ractopamine at 50 to 400 mg/kg, the average recoveries were 105.5 to 111.4% by ELISA and 89.1 to 92.9% by HPLC. The limit of detection was 0.24 microg/g by ELISA and 0.48 microg/g by HPLC, respectively. Results from the swine complex feeds (P = 0.009) and the supplement (P = 0.005) using ELISA and HPLC were not highly correlated. The ELISA was more sensitive and rapid and less expensive than the HPLC method and could be used for ractopamine screening in swine feeds before confirmation and quantification by other methods, such as HPLC.
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Alimentación Animal/análisis , Anticuerpos Monoclonales , Ensayo de Inmunoadsorción Enzimática/métodos , Fenetilaminas/análisis , Porcinos , Agonistas Adrenérgicos beta/análisis , AnimalesRESUMEN
AIM: To test whether inhibition of sarcoplasmic reticulum (SR) Ca2+-pump is involved in H2O2-induced contraction of endothelium-denuded rat aorta. METHODS: Isometric tension recording of H2O2 and cyclopiazonic acid (CPA)-induced contractions of rat aortic rings were compared in the absence or presence of various pharmacological tools to discriminate their signaling pathways involved. RESULTS: Both H2O2 and CPA contracted rat aortic rings, but with different contractile patterns. H2O2 triggered a fast and phasic contraction, whereas CPA elicited a slow and sustained contraction. In Ca2+-free medium, pretreatment of aortic rings with CPA 30 micromol/L but not with H2O2 30 micromol/L nearly abolished phenylephrine (10 micromol/L)-induced contraction. In addition, upon the maximal contraction induced by thapsigargin 30 micromol/L, H2O2 but not CPA further contracted aortic rings. On the other hand, H2O2 (30 micromol/L)- but not CPA (10 micromol/L)-induced contraction could be inhibited by suramin and RB-2 (each 100 micromol/L), two P2-purinoceptor antagonists. Furthermore, although pretreatment with 2-APB, a membrane permeable IP3 receptor blocker, inhibited both H2O2- and CPA-induced contractions, only H2O2 (30 micromol/L)-induced contraction could be depressed, to different degree, by various inhibitors of receptor-coupled or downstream signaling enzymes, including PLC, PKC, PLA2, COX, and protein tyrosine kinases. CONCLUSION: Inhibition of smooth muscle SR Ca2+-pump is unlikely the mechanism responsible for H2O2-induced contraction of endothelium-denuded rat aorta.
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ATPasa de Ca(2+) y Mg(2+)/metabolismo , Peróxido de Hidrógeno/farmacología , Indoles/farmacología , Contracción Muscular/efectos de los fármacos , Retículo Sarcoplasmático/enzimología , Animales , Aorta Torácica/efectos de los fármacos , Compuestos de Boro/farmacología , Endotelio Vascular/fisiología , Técnicas In Vitro , Masculino , Músculo Liso Vascular/efectos de los fármacos , Antagonistas del Receptor Purinérgico P2 , Ratas , Ratas Sprague-Dawley , Suramina/farmacologíaRESUMEN
OBJECTIVE: H(2)O(2) can contract many arteries, however the underlying mechanisms are not fully understood. This study aims to test whether H(2)O(2)-induced vasoconstriction could be functionally attributed to the activation of P(2)-purinoceptors in rat aorta and to explore its possible signaling mechanisms. METHODS: Isometric tension recording of H(2)O(2) and ATP-induced contractions of rat aortic rings were compared in the absence or presence of various pharmacological tools to identify their possible common signaling pathways. RESULTS: Both H(2)O(2) and ATP induced transient phasic contractions in a concentration-dependent manner (1-1000 microM). Removal of endothelium potentiated the contractile responses to H(2)O(2) and to ATP. H(2)O(2) (30 microM)-induced phasic contraction could be abolished by catalase (800 U/ml), but not affected by SOD (150 U/ml), DMSO (5 mM) and apyrase (5 U/ml), suggesting no involvement of O(2)(-), hydroxyl free radicals and ATP release. Also, several receptor antagonists including phentolamine, atropine, methysergide and chlorpheniramine (each 3 microM) were without effect on H(2)O(2) (30 microM)-induced phasic contraction, suggesting no involvement of typical neurotransmitter release. However, both H(2)O(2) (30 microM) and ATP (1 mM)-induced phasic contractions not only presented homologous desensitization, but also showed heterogeneous desensitization. Furthermore, the phasic contractions in response to H(2)O(2) (30 microM) or ATP (100 microM) could be inhibited or abolished in a concentration dependent manner by RB-2 and suramin (10-100 microM), two widely used P(2)-purinoceptor antagonists, with only partial inhibition by Evans blue (300 microM), a moderately selective P(2x) receptor blocker, or by alpha-beta-methylene-ATP (100 microM), a selective P(2x) receptor desensitizer. On the other hand, both H(2)O(2) (30 microM) and ATP (100 microM)-induced phasic contractions were also attenuated, to different degree, by inhibitors of several enzymes including PLC, PKC, PLA(2) and cyclooxygenase. Lastly, removal of extracellular Ca(2+) or pretreatment with procaine (10 mM) and dantrolene (30 microM), two putative intracellular Ca(2+) release blockers, or with Ni(2+) (100 microM) and tetrandrine (5 microM), two Ca(2+) channel blockers, all significantly inhibited H(2)O(2) and ATP-induced contractions. However, nifedipine (1 microM), a voltage-dependent L-type Ca(2+) channel blocker, was without effect. CONCLUSIONS: Our results demonstrate that H(2)O(2)-induced phasic contraction of rat aorta involves, at least in part, the activation of P(2)-purinoceptors in the aortic smooth muscle cells
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Bencilisoquinolinas , Peróxido de Hidrógeno/farmacología , Músculo Liso Vascular/metabolismo , Antagonistas del Receptor Purinérgico P2 , Transducción de Señal , Vasoconstrictores/farmacología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/farmacología , Alcaloides/farmacología , Análisis de Varianza , Animales , Aorta , Apirasa/farmacología , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Catalasa/farmacología , Dantroleno/farmacología , Dimetilsulfóxido/farmacología , Relación Dosis-Respuesta a Droga , Azul de Evans/farmacología , Técnicas In Vitro , Masculino , Músculo Liso Vascular/efectos de los fármacos , Níquel/farmacología , Nifedipino/farmacología , Procaína/farmacología , Ratas , Ratas Sprague-Dawley , Receptores Purinérgicos P2/metabolismo , Superóxido Dismutasa/farmacología , Suramina/farmacología , Triazinas/farmacologíaRESUMEN
This study aims to examine the effects of different reactive oxygen species (ROS) on the resting tension of endothelium-denuded rat aortic rings. In these preparations, H2O2 (30 microM) induced a fast and transient contraction, which could be abolished by pretreatment of catalase (800 U/ml), but not affected by superoxide anion scavenger, superoxide dismutase (SOD; 150 U/ml) or the hydroxyl free radical scavenger, DMSO/mannitol (each 3 mM). In contrast, pyrogallol, a putative superoxide anion donor, induced a biphasic contraction, which could be abolished by SOD, but not by catalase or DMSO/mannitol. Unlike H2O2 and pyrogallol, Vitamin C(VitC)/Fe2+ (each 100 microM), a commonly used hydroxyl radical-generating system, triggered a tonic contraction which could be prevented by DMSO/mannitol, but not by SOD or catalase. Interestingly, H2O2-induced contraction could be concentration-dependently (10-100 microM) inhibited by suramin and reactive blue-2 (RB-2), two widely used ATP receptor antagonists. On the other hand, suramin or RB-2, at concentration up to 100 microM, affected neither pyrogallol nor VitC/Fe2+-induced contraction. In conclusion, we showed for the first time that different ROS could contract rat aorta with different mechanisms of action, and H2O2 elicits a transient contraction probably as a result of the ATP receptor activation.
Asunto(s)
Peróxido de Hidrógeno/farmacología , Músculo Liso Vascular/efectos de los fármacos , Especies Reactivas de Oxígeno , Receptores Purinérgicos P2/metabolismo , Vasoconstricción/efectos de los fármacos , Animales , Aorta , Ácido Ascórbico/farmacología , Compuestos Ferrosos/farmacología , Masculino , Pirogalol/farmacología , Ratas , Ratas Sprague-Dawley , Suramina/farmacología , Triazinas/farmacologíaRESUMEN
OBJECTIVE: To explore the characteristic of normal voice in different age-bracket of Chinese adults and to formulate the normal reference value suited to our country at voice assessment. METHOD: We divided the adults into the youth, the middle-aged and the old groups, and analyzed normal voice samples with Dr. Speech software and computer multimedia technique and compared the following 5 parameters (Jitter, Shimmer, NNE, Fo and SDFo) of different groups divided according to one's age, sex and vowel. RESULT: There is difference among the group of age, sex and vowel in most acoustic parameters in the adults. CONCLUSION: To initiate taking multi-vowels samples and using different normal reference value and multi-parameters analysis according to the difference of age-bracket, sex and vowel in the adults.