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1.
Clin Genet ; 87(3): 279-83, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24635491

RESUMEN

Andersen-Tawil syndrome (ATS) is an inherited disease characterized by ventricular arrhythmias, periodic paralysis, and dysmorphic features. It results from a heterozygous mutation of KCNJ2, but little is known about mosaicism in ATS. We performed genetic analysis of KCNJ2 in 32 ATS probands and their family members and identified KCNJ2 mutations in 25 probands, 20 families who underwent extensive genetic testing. These tests revealed that seven probands carried de novo mutations while 13 carried inherited mutations from their parents. We then specifically assessed a single proband and the respective family. The proband was a 9 year old girl who fulfilled the ATS triad and carried an insertion mutation (p.75_76insThr). We determined that the proband's mother carried a somatic mosaicism and that the proband's younger brother also carried the ATS phenotype with the same insertion mutation. The mother, who exhibited mosaicism, was asymptomatic, although she exhibited Q(T)U prolongation. Mutant allele frequency was 11% as per TA cloning and 17.3% as per targeted deep sequencing. Our observations suggest that targeted deep sequencing is useful for the detection of mosaicism and that the detection of mosaic mutations in parents of apparently sporadic ATS patients can help in the process of genetic counseling.


Asunto(s)
Síndrome de Andersen/diagnóstico , Síndrome de Andersen/genética , Mosaicismo , Mutación , Canales de Potasio de Rectificación Interna/genética , Alelos , Electrocardiografía , Femenino , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Linaje , Fenotipo
2.
Euro Surveill ; 20(20)2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-26027484

RESUMEN

We isolated eight highly pathogenic H5N8 avian influenza viruses (H5N8 HPAIVs) in the 2014/15 winter season at an overwintering site of migratory birds in Japan. Genetic analyses revealed that these isolates were divided into three groups, indicating the co-circulation of three genetic groups of H5N8 HPAIV among these migratory birds. These results also imply the possibility of global redistribution of the H5N8 HPAIVs via the migration of these birds next winter.


Asunto(s)
Migración Animal , Aves/virología , Variación Genética , Virus de la Influenza A/genética , Virus de la Influenza A/aislamiento & purificación , Animales , Virus de la Influenza A/clasificación , Virus de la Influenza A/patogenicidad , Gripe Aviar/virología , Japón , Filogenia , Estaciones del Año , Análisis de Secuencia de ADN
3.
Osteoarthritis Cartilage ; 22(7): 941-50, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24795274

RESUMEN

OBJECTIVE: A new strategy is required in order to regenerate a meniscus for extensive defects. Synovial mesenchymal stem cells (MSCs) are an attractive cell source for meniscus regeneration due to their high proliferation and chondrogenic potential. We examined the effect of repetitive intraarticular injections of synovial MSCs on meniscus regeneration in a massive meniscal defect of pigs. We followed up the efficacy using MRI evaluation in addition to macroscopic and histological observations. DESIGN: Two weeks before the injection of synovial MSCs, the anterior half of the medial menisci was resected in both knees of pigs. Fifty million allogeneic synovial MSCs were injected into the right knee at 0, 2, and 4 weeks and followed up by sequential MRI. The regenerated meniscus, adjacent articular cartilage, and subchondral bone were evaluated by MRI at 2, 4, 8, 12 and 16 weeks. They were also evaluated macroscopically and histologically at 16 weeks (n = 7). RESULTS: The resected meniscus regenerated significantly better in the MSC group than in the control group based on histological and MRI analyses. Macroscopically, the meniscal defect already appeared to be filled with synovial tissue at 2 weeks. Articular cartilage and subchondral bone at the medial femoral condyle were also significantly more preserved in the MSC group based on MRI, macroscopic, and histological analyses. CONCLUSIONS: Intraarticular injections of allogeneic synovial MSCs appeared to promote meniscus regeneration and provide protection at the medial femoral articular cartilage in a porcine massive meniscal defect model.


Asunto(s)
Traumatismos de la Rodilla/terapia , Meniscos Tibiales/fisiología , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Regeneración/fisiología , Aloinjertos , Animales , Cartílago Articular/patología , Inyecciones Intraarticulares , Traumatismos de la Rodilla/patología , Imagen por Resonancia Magnética , Meniscos Tibiales/cirugía , Modelos Animales , Porcinos , Membrana Sinovial/patología , Lesiones de Menisco Tibial , Resultado del Tratamiento
4.
J Chem Phys ; 138(21): 214305, 2013 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-23758369

RESUMEN

Differential, integral, and momentum transfer cross sections have been determined for the elastic scattering of electrons from the molecules CF3Cl, CF2Cl2, and CFCl3.With the help of a crossed electron beam-molecular beam apparatus using the relative flow technique, the ratios of the elastic differential cross sections (DCSs) of CF3Cl, CF2Cl2, and CFCl3 to those of He were measured in the energy region from 1.5 to 100 eV and at scattering angles in the range 15° to 130°. From those ratios, the absolute DCSs were determined by utilizing the known DCS of He. For CF3Cl and CF2Cl2, at the common energies of measurement, we find generally good agreement with the results from the independent experiments of Mann and Linder [J. Phys. B 25, 1621 (1992); and ibid. 25, 1633 (1992)]. In addition, as a result of progressively substituting a Cl-atom, undulations in the angular distributions have been found to vary in a largely systematic manner in going from CF4 to CF3Cl to CF2Cl2 to CFCl3 and to CCl4. These observed features suggest that the elastic scattering process is, in an independently additive manner, dominated by the atomic-Cl atoms of the molecules. The present independent atom method calculation typically supports the experimental evidence, within the screened additivity rule formulation, for each species and for energies greater than about 10-20 eV. Integral elastic and momentum transfer cross sections were also derived from the measured DCSs, and are compared to the other available theoretical and experimental results. The elastic integral cross sections are also evaluated as a part of their contribution to the total cross section.

5.
Osteoarthritis Cartilage ; 20(10): 1197-207, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22750747

RESUMEN

OBJECTIVE: Meniscal regeneration was previously shown to be enhanced by injection of mesenchymal stem/stromal cells (MSCs) but the mode of action of the MSCs was not established. The aim of this study was to define how injection of MSCs enhances meniscal regeneration. DESIGN: A hemi-meniscectomy model in rats was used. Rat-MSCs (rMSCs) or human-MSCs (hMSCs) were injected into the right knee joint after the surgery, and PBS was injected into the left. The groups were compared macroscopically and histologically at 2, 4, and 8 weeks. The changes in transcription in both human and rat genes were assayed by species-specific microarrays and real-time RT-PCRs. RESULTS: Although the number of hMSCs decreased with time, hMSCs enhanced meniscal regeneration in a manner similar to rMSCs. hMSCs injection increased expression of rat type II collagen (rat-Col II), and inhibited osteoarthritis progression. The small fraction of hMSCs was activated to express high levels of a series of genes including Indian hedgehog (Ihh), parathyroid hormone-like hormone (PTHLH), and bone morphogenetic protein 2 (BMP2). The presence of hMSCs triggered the subsequent expression of rat-Col II. An antagonist of hedgehog signaling inhibited the expression of rat-Col II and an agonist increased expression of rat-Col II in the absence of hMSCs. CONCLUSIONS: Despite rapid reduction in cell numbers, intra-articular injected hMSCs were activated to express Ihh, PTHLH, and BMP2 and contributed to meniscal regeneration. The hedgehog signaling was essential in enhancing the expression of rat-Col II, but several other factors provided by the hMSCs probably contributed to the repair.


Asunto(s)
Colágeno Tipo II/genética , Proteínas Hedgehog/genética , Meniscos Tibiales/patología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Regeneración/fisiología , Animales , Proteína Morfogenética Ósea 2/genética , Proteína Morfogenética Ósea 2/metabolismo , Recuento de Células , Trasplante de Células , Colágeno Tipo II/metabolismo , Modelos Animales de Enfermedad , Expresión Génica , Proteínas Hedgehog/metabolismo , Humanos , Inyecciones Intraarticulares , Masculino , Meniscos Tibiales/metabolismo , Células Madre Mesenquimatosas/metabolismo , Ratas , Ratas Endogámicas Lew
6.
Pharmacopsychiatry ; 45(7): 279-83, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22592502

RESUMEN

An increased incidence of sudden death has been observed among patients treated with antidepressants. A prolonged QTc interval is a known prognostic factor for fatal arrhythmia, and several studies have shown that the use of antidepressants can cause a prolonged QTc interval. However, few studies, especially in Japan, have compared the effects of multiple drugs on QTc interval or examined dose relationships in a clinical setting.We compared the effects of antidepressants on QT interval, corrected to QTc by Bazett's formula, in 729 Japanese patients who were diagnosed with mood disorder.Using stepwise multiple linear regression analysis, we found that the use of tricyclic antidepressants (P<0.01) and concomitant use of antipsychotics (P<0.05), as well as advanced age and being female (known factors for prolonged QTc interval; both P<0.01), significantly prolonged the QTc interval. Analysis of individual antidepressants also revealed that the use of clomipramine (P<0.01) and amitriptyline (P<0.05) significantly prolonged the QTc interval.Our results reveal that tricyclic antidepressants, especially clomipramine and amitriptyline, confer a risk of prolonged QTc interval in a dose-dependent manner. The selective serotonin reuptake inhibitors investigated (fluvoxamine, paroxetine, sertraline) were not indicated as risk factors for QTc prolongation.


Asunto(s)
Antidepresivos Tricíclicos/efectos adversos , Antipsicóticos/efectos adversos , Pueblo Asiatico/psicología , Síndrome de QT Prolongado/inducido químicamente , Trastornos del Humor/fisiopatología , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Factores de Edad , Antidepresivos Tricíclicos/administración & dosificación , Antipsicóticos/administración & dosificación , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada/efectos adversos , Electrocardiografía/psicología , Electrocardiografía/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Humor/tratamiento farmacológico , Análisis de Regresión , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Caracteres Sexuales
7.
J Chem Phys ; 135(23): 234309, 2011 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-22191877

RESUMEN

We report absolute elastic differential, integral and momentum transfer cross sections for electron interactions with CCl(4). The incident electron energy range is 1.5-100 eV, and the scattered electron angular range for the differential measurements varies from 15°-130°. The absolute scale of the differential cross section was set using the relative flow technique with helium as the reference species. Comparison with previous total cross sections shows good agreement. Atomic-like behaviour in this scattering system is shown here for the first time, and is further investigated by comparing the CCl(4) elastic cross sections to recent results on the halomethanes and atomic chlorine at higher impact energies [H. Kato, T. Asahina, H. Masui, M. Hoshino, H. Tanaka, H. Cho, O. Ingólfsson, F. Blanco, G. Garcia, S. J. Buckman, and M. J. Brunger, J. Chem. Phys. 132, 074309 (2010)].

8.
Int J Sports Med ; 32(7): 559-64, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21567354

RESUMEN

Erythropoietin promotes the production of red blood cells. Recombinant human erythropoietin is illicitly used to improve performance in endurance sports. Expression of the ERYTHROPOIETIN gene is negatively controlled by the transcription factor GATA-binding protein (GATA). Specific GATA inhibitors have recently been developed as novel drugs for the management of anemia. These drugs could, therefore, be illicitly used like recombinant human erythropoietin to improve performance in sports. To examine alterations in levels of plasma protein after administration of GATA inhibitors, proteomic analyses were conducted on mouse plasma samples treated with the potent GATA inhibitor K-11706. The analysis based on gel electrophoresis identified 41 protein spots differentially expressed when compared with normal plasma. Each spot was identified with liquid chromatography coupled to tandem mass spectrometry and 2 of them, fetuin-B and prothrombin, were verified by Western blotting. The results showed that the expression of fetuin-B in mice plasma was increased by K-11706, but not by recombinant human erythropoietin or hypoxia. These results suggest the potential of proteomic-based approaches as tools to identify biomarkers for the illegal use of novel drugs (e.g., GATA inhibitors). Also, fetuin-B could be a sensitive marker for the detection of abuse of GATA inhibitors.


Asunto(s)
Factores de Transcripción GATA/antagonistas & inhibidores , Proteómica/métodos , Animales , Biomarcadores/sangre , Western Blotting , Cromatografía Liquida , Doping en los Deportes , Electroforesis en Gel de Poliacrilamida , Eritropoyetina/farmacología , Fetuína-B , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos ICR , Protrombina/efectos de los fármacos , Protrombina/genética , Protrombina/metabolismo , Proteínas Recombinantes , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem , alfa-Fetoproteínas/efectos de los fármacos , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
9.
Microbiol Resour Announc ; 10(30): e0051821, 2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34323616

RESUMEN

Lactiplantibacillus pentosus AWA1501 was isolated from the traditional Japanese tea Awa-bancha. Previous studies have reported that this species becomes predominant after the anaerobic fermentation process. In this study, we report the whole-genome sequence of this strain. The draft genome sequence comprises 3,714,221 nucleotides and 3,374 coding DNA sequences, with an average G+C content of 46.02%.

10.
Int J Sports Med ; 30(7): 485-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19455480

RESUMEN

Caffeine enhances endurance performance; however, its effect on accumulated lactate remains unclear. Conversely, taurine, which also enhances endurance performance, decreases accumulated lactate. In this study, the effect of combination of caffeine and taurine on endurance performance was assessed. Mice ran on a treadmill, and the accumulated lactate was measured. In addition, muscle fibers from the gastrocnemius muscle of the mice were stained with ATPase and analyzed. The use of caffeine and taurine over a 2 week period enhanced endurance performance. Moreover, taurine significantly decreased the accumulated concentration of lactate over long running distances. However, the diameter of the cross-sections and ratios of Types I, IIA, and IIB muscle fibers were not affected.


Asunto(s)
Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Resistencia Física/efectos de los fármacos , Taurina/farmacología , Animales , Prueba de Esfuerzo , Ácido Láctico/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Fibras Musculares Esqueléticas/efectos de los fármacos
11.
QJM ; 112(5): 343-350, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30690642

RESUMEN

BACKGROUND: Brugada syndrome (BrS) is a heritable sudden cardiac death (SCD) disease with male predominance. Information on gender difference of BrS remains scarce. AIM: To investigate the gender difference of BrS in Han Chinese. DESIGN: We consecutively enrolled 169 BrS patients (153 males and 16 females) from Han Chinese in Taiwan from 1998 to 2017. METHODS: Clinical characteristics, electrocardiographic parameters and SCN5A mutation status were compared between genders. RESULTS: The percentage of family history of SCD in females was slightly higher (31.3% vs. 15%, P = 0.15). Females exhibited longer QTc (457.8 ± 33.0 vs. 429.5 ± 42.1 ms, P < 0.01). Regarding cumulative event occurrence by age, Mantel-Cox test showed females had earlier age of onset of first cardiac events (SCD or syncope) than males (P = 0.049), which was mainly attributed to syncope (P < 0.01). Males with SCD exhibited longer QRS duration (114.2 ± 26.8 vs. 104.8 ± 15.3 ms, P = 0.02) and QTc (442.5 ± 57.4 vs. 422.9 ± 28.8 ms, P = 0.02). Males with syncope exhibited longer PR interval (181.2 ± 33.7 vs. 165.7 ± 27.1 ms, P = 0.01), whereas females with SCD or syncope had a trend towards slower heart rates (69.1 ± 9.6 vs. 82.2 ± 16.3 bpm, P = 0.10) than female with no or mild symptoms. There was no difference in the percentage of SCN5A mutation between genders. CONCLUSION: Gender difference is present in BrS. Females have longer QTc and suffer from syncope earlier than males. Risk of SCD in males is associated with boarder QRS complex and longer QTc, whereas risk of syncope is associated with longer PR interval in males and slower heart rate in females.


Asunto(s)
Síndrome de Brugada/genética , Muerte Súbita Cardíaca/epidemiología , Síndrome de QT Prolongado/epidemiología , Canal de Sodio Activado por Voltaje NAV1.5/genética , Factores Sexuales , Síncope/etiología , Adulto , Síndrome de Brugada/complicaciones , Síndrome de Brugada/fisiopatología , Muerte Súbita Cardíaca/etiología , Electrocardiografía , Femenino , Humanos , Síndrome de QT Prolongado/etiología , Masculino , Persona de Mediana Edad , Mutación , Sistema de Registros , Medición de Riesgo , Distribución por Sexo , Síncope/epidemiología , Taiwán/epidemiología
12.
J Clin Invest ; 91(3): 1231-4, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7680665

RESUMEN

The pathogenesis of myocarditis and dilated cardiomyopathy is though to involve autoimmunological processes and myocardial calcium overload. Serum containing antiheart antibodies associated with a murine model of myocarditis increased [Ca2+]i in guinea pig ventricular myocytes only in the presence of extracellular Ca2+. The antiheart antibody-positive serum activated Ca(2+)-permeable cation channels that were insensitive to dihydropyridines and membrane stretch. The permeability sequence was Ba2+ > Ca2+ > Na+ approximately K+, and the single-channel conductance to Ba2+ was 12 pS. The channel was activated by extracellular application of the serum during on-cell recording, which suggests that a soluble intracellular messenger may be involved. The antibody-positive serum did not alter voltage-gated Ca2+ currents. We propose that excess Ca entry in myocarditis and dilated cardiomyopathy results from activation of a Ca(2+)-permeable cationic channel by the autoantibodies.


Asunto(s)
Anticuerpos/farmacología , Calcio/metabolismo , Canales Iónicos/fisiología , Miocarditis/inmunología , Miocardio/inmunología , Animales , Anticuerpos/sangre , Anticuerpos/aislamiento & purificación , Bario/metabolismo , Cationes , Fura-2 , Cobayas , Ventrículos Cardíacos , Masculino , Potenciales de la Membrana , Ratones , Ratones Endogámicos BALB C , Miocarditis/sangre , Miocardio/metabolismo
13.
J Clin Invest ; 100(12): 3053-9, 1997 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9399952

RESUMEN

The cardiac ATP-sensitive potassium (KATP) channel is thought to be a complex composed of an inward rectifier potassium channel (Kir6.1 and/or Kir6.2) subunit and the sulfonylurea receptor (SUR2). This channel is activated during myocardial ischemia and protects the heart from ischemic injury. We examined the transcriptional expression of these genes in rats with myocardial ischemia. 60 min of myocardial regional ischemia followed by 24-72 h, but not 3-6 h, of reperfusion specifically upregulated Kir6.1 mRNA not only in the ischemic (approximately 2.7-3.1-fold) but also in the nonischemic (approximately 2.0-2.6-fold) region of the left ventricle. 24 h of continuous ischemia without reperfusion also induced an increase in Kir6.1 mRNA in both regions, whereas 15-30 min of ischemia followed by 24 h of reperfusion did not induce such expression. In contrast, mRNAs for Kir6.2 and SUR2 remained unchanged under these ischemic procedures. Western blotting demonstrated similar increases in the Kir6.1 protein level both in the ischemic (2.4-fold) and the nonischemic (2.2-fold) region of rat hearts subjected to 60 min of ischemia followed by 24 h of reperfusion. Thus, prolonged myocardial ischemia rather than reperfusion induces delayed and differential regulation of cardiac KATP channel gene expression.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Regulación de la Expresión Génica , Isquemia Miocárdica/metabolismo , Miocardio/metabolismo , Canales de Potasio de Rectificación Interna , Canales de Potasio/genética , Receptores de Droga/genética , Animales , Modelos Animales de Enfermedad , Hemodinámica , Masculino , Isquemia Miocárdica/genética , Canales de Potasio/biosíntesis , Ratas , Ratas Wistar , Receptores de Droga/biosíntesis , Receptores de Sulfonilureas
14.
J Clin Invest ; 97(11): 2417-25, 1996 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-8647933

RESUMEN

In genetically occurring non-insulin-dependent diabetes mellitus (NIDDM) model rats (GK rats), the activities of L- and T-type Ca2+ channels in pancreatic beta cells are found to be augmented, by measuring the Ba2+ currents via these channels using whole-cell patch-clamp technique, while the patterns of the current-voltage curves are indistinguishable. The hyper-responsiveness of insulin secretion to nonglucose depolarizing stimuli observed in NIDDM beta cells could be the result, therefore, of increased voltage-dependent Ca2+ channel activity. Perforated patch-clamp recordings reveal that the augmentation of L-type Ca2+ channel activity by glucose is markedly less pronounced in GK beta cells than in control beta cells, while glucose-induced augmentation of T-type Ca2+ channel activity is observed neither in the control nor in the GK beta cells. This lack of glucose-induced augmentation of L-type Ca2+ channel activity in GK beta cells might be causatively related to the selective impairment of glucose-induced insulin secretion in NIDDM beta cells, in conjunction with an insufficient plasma membrane depolarization due to impaired closure of the ATP-sensitive K+ channels caused by the disturbed intracellular glucose metabolism in NIDDM beta cells.


Asunto(s)
Canales de Calcio/fisiología , Diabetes Mellitus Tipo 2/fisiopatología , Glucosa/farmacología , Insulina/metabolismo , Islotes Pancreáticos/fisiopatología , Animales , Calcio/metabolismo , Canales de Calcio/efectos de los fármacos , Canales de Calcio Tipo L , Células Cultivadas , Diabetes Mellitus Tipo 2/patología , Secreción de Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/patología , Masculino , Potenciales de la Membrana/efectos de los fármacos , Modelos Biológicos , Nitrendipino/metabolismo , Técnicas de Placa-Clamp , Potasio/farmacología , Ratas , Ratas Mutantes , Ratas Wistar , Valores de Referencia
15.
Br J Pharmacol ; 150(8): 1011-21, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17339832

RESUMEN

BACKGROUND AND PURPOSE: Protein kinase C (PKC) comprises at least twelve isoforms and has an isoform-specific action on cardiac electrical activity. The slow component of delayed rectifier K(+) current (I (Ks)) is one of the major repolarizing currents in the hearts of many species and is also potentiated by PKC activation. Little is known, however, about PKC isoform(s) functionally involved in the potentiation of I (Ks) in native cardiac myocytes. EXPERIMENTAL APPROACH: I (Ks) was recorded from guinea-pig atrial myocytes, using the whole-cell configuration of patch-clamp method. KEY RESULTS: Bath application of phenylephrine enhanced I (Ks) concentration-dependently with EC(50) of 5.4 microM and the maximal response (97.1+/-11.9% increase, n=16) was obtained at 30 microM. Prazosin (1 microM) almost totally abolished the potentiation of I (Ks) by phenylephrine, supporting the involvement of alpha(1)-adrenoceptors. The stimulatory action of phenylephrine was significantly, if not entirely, inhibited by the general PKC inhibitor bisindolylmaleimide I but was little affected by Gö-6976, Gö-6983 and rottlerin. Furthermore, this stimulatory effect was significantly reduced by dialyzing atrial myocytes with PKCepsilon-selective inhibitory peptide epsilonV1-2 but was not significantly affected by conventional PKC isoform-selective inhibitory peptide betaC2-4. Phorbol 12-myristate 13-acetate (PMA) at 100 nM substantially increased I (Ks) by 64.2+/-1.3% (n=6), which was also significantly attenuated by an internal dialysis with epsilonV1-2 but not with betaC2-4. CONCLUSIONS AND IMPLICATIONS: The present study provides experimental evidence to suggest that, in native guinea-pig cardiac myocytes, activation of PKC contributes to alpha(1)-adrenoceptor-mediated potentiation of I (Ks) and that epsilon is the isoform predominantly involved in this PKC action.


Asunto(s)
Canales de Potasio de Tipo Rectificador Tardío/metabolismo , Miocitos Cardíacos/metabolismo , Proteína Quinasa C-epsilon/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Agonistas alfa-Adrenérgicos/farmacología , Antagonistas Adrenérgicos alfa/farmacología , Animales , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Cobayas , Atrios Cardíacos/citología , Atrios Cardíacos/metabolismo , Técnicas In Vitro , Indoles/farmacología , Isoenzimas/metabolismo , Maleimidas/farmacología , Potenciales de la Membrana , Miocitos Cardíacos/efectos de los fármacos , Técnicas de Placa-Clamp , Fragmentos de Péptidos/farmacología , Fenilefrina/farmacología , Prazosina/farmacología , Proteína Quinasa C-epsilon/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Receptores Adrenérgicos alfa 1/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología , Factores de Tiempo
16.
Cancer Res ; 53(22): 5350-4, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-7693338

RESUMEN

We have developed a highly sensitive method for detecting prostate cancer cells using reverse transcriptase-polymerase chain reaction (RT-PCR) with primers specific for prostate-specific antigen gene. Forty-four lymph nodes obtained from 22 patients with prostate cancers were analyzed by RT-PCR to detect metastatic prostate cancer cells. RT-PCR could detect prostate-specific antigen mRNA in five lymph nodes with histologically and/or immunohistochemically identifiable metastases and in four lymph nodes with negative histological and immunohistochemical analyses for metastases. RT-PCR was a more sensitive method than histology and immunohistochemistry in detecting metastatic prostate cancer cells and could be applied for diagnosing micrometastases of prostate cancer to lymph nodes. This highly sensitive RT-PCR will be a relevant tool to allow a more accurate clinical assessment of lymph node metastases of prostate cancer and to understand lymphatic dissemination of prostate cancer biologically.


Asunto(s)
Ganglios Linfáticos/química , Antígeno Prostático Específico/análisis , Neoplasias de la Próstata/química , ARN Mensajero/análisis , ARN Neoplásico/análisis , Secuencia de Bases , Southern Blotting , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Neoplasias de la Próstata/patología , Sensibilidad y Especificidad
17.
J Neurosci ; 19(22): 9964-74, 1999 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-10559404

RESUMEN

The signals that prompt the axons to send out processes in peripheral nerves after axotomy are not well understood. Here, we report that galectin-1 can play an important role in this initial stage. We developed an in vitro nerve regeneration model that allows us to monitor the initial axon and support cell outgrowth from the proximal nerve stump, which is comparable to the initial stages of nerve repair. We isolated a factor secreted from COS1 cells that enhanced axonal regeneration, and we identified the factor as galectin-1. Recombinant human galectin-1 (rhGAL-1) showed the same activity at low concentrations (50 pg/ml) that are two orders of magnitude lower than those of lectin activity. A similarly low concentration was also effective in in vivo experiments of axonal regeneration with migrating reactive Schwann cells to a grafted silicone tube after transection of adult rat peripheral nerve. Moreover, the application of functional anti-rhGAL-1 antibody strongly inhibited the regeneration in vivo as well as in vitro. The same effect of rhGAL-1 was confirmed in crush/freeze experiments of the adult mouse sciatic nerve. Because galectin-1 is expressed in the regenerating sciatic nerves as well as in both sensory neurons and motor neurons, we suggest that galectin-1 may regulate initial repair after axotomy. This high activity of the factor applied under nonreducing conditions suggests that galectin-1 may work as a cytokine, not as a lectin.


Asunto(s)
Axones/fisiología , Ganglios Espinales/fisiología , Hemaglutininas/farmacología , Regeneración Nerviosa/fisiología , Nervio Ciático/fisiología , Animales , Axones/efectos de los fármacos , Axones/ultraestructura , Axotomía , Células COS , Clonación Molecular , Medio de Cultivo Libre de Suero , Femenino , Galectina 1 , Hemaglutininas/fisiología , Humanos , Hígado/metabolismo , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica , Compresión Nerviosa , Regeneración Nerviosa/efectos de los fármacos , Técnicas de Cultivo de Órganos , Fragmentos de Péptidos/química , Ratas , Ratas Wistar , Proteínas Recombinantes/farmacología , Células de Schwann/fisiología , Nervio Ciático/lesiones
18.
Biochim Biophys Acta ; 1568(1): 74-82, 2001 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-11731088

RESUMEN

An aqueous acetone extract of the pericarps of Mallotus japonicus (MJE) inhibited nitric oxide (NO) production by a murine macrophage-like cell line, RAW 264.7, which was activated by lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). Seven phloroglucinol derivatives isolated from MJE exhibited inhibitory activity against NO production. Among these phloroglucinol derivatives, isomallotochromanol exhibited strong inhibitory activity toward NO production, exhibiting an IC(50) of 10.7 microM. MJE and the phloroglucinol derivatives significantly reduced both the induction of inducible nitric oxide synthase (iNOS) protein and iNOS mRNA expression. NO production by macrophages preactivated with LPS and IFN-gamma for 16 h was also inhibited by MJE and the phloroglucinol derivatives. Furthermore, MJE and the derivatives directly affected the conversion of L-[(14)C]arginine to L-[(14)C]citrulline by the cell extract. These results suggest that MJE and the phloroglucinol derivatives have the pharmacological ability to suppress NO production by activated macrophages. They inhibited NO production by two mechanisms: reduction of iNOS protein induction and inhibition of enzyme activity.


Asunto(s)
Euphorbiaceae , Macrófagos/efectos de los fármacos , Óxido Nítrico/biosíntesis , Floroglucinol/análogos & derivados , Animales , Línea Celular , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Interferón gamma , Lipopolisacáridos , Activación de Macrófagos , Macrófagos/metabolismo , Ratones , Estructura Molecular , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Floroglucinol/farmacología , Extractos Vegetales/farmacología , ARN Mensajero/biosíntesis
19.
Biochim Biophys Acta ; 1168(1): 45-51, 1993 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-8504141

RESUMEN

NB-598, a specific inhibitor of squalene epoxidase, suppressed the secretion of cholesterol and triacylglycerol from HepG2 cells into the medium. L-654,969, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, inhibited the secretion of cholesterol as potently as NB-598, but did not suppress the secretion of triacylglycerol. Both compounds decreased the intracellular cholesterol content almost equally, and neither of the compounds reduced the intracellular triacylglycerol content. The suppression of lipid secretion by NB-598 was associated with a significant reduction in apolipoprotein (apo) B secretion into the medium. Therefore, the suppression of lipid secretion by NB-598 may be caused by a reduction in the number of triacylglycerol-rich lipoprotein particles. In contrast, the suppression of cholesterol secretion by L-654,969 may be due to a modulation of lipoprotein lipid composition, since this agent did not reduce the secretion of apo B or triacylglycerol. The secretion of apo A-I was unaffected by either NB-598 or L-654,969. Pulse chase studies using [35S]methionine showed that the suppression of apo B secretion by NB-598 depended on an enhancement of intracellular degradation of apo B. These results indicate that the secretion of apo B from HepG2 cells is not regulated by the lipid synthesis alone, and suggest that the mechanism of the hypolipidemic effect of NB-598 involves the suppression of triacylglycerol-rich lipoprotein secretion from the liver as well as an inhibition of cholesterol synthesis in the liver.


Asunto(s)
Anticolesterolemiantes/farmacología , Apolipoproteínas B/metabolismo , Bencilaminas/farmacología , Colesterol/metabolismo , Oxigenasas/antagonistas & inhibidores , Simvastatina/análogos & derivados , Tiofenos/farmacología , Triglicéridos/metabolismo , Apolipoproteína A-I/biosíntesis , Apolipoproteína A-I/metabolismo , Apolipoproteínas B/biosíntesis , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Hígado/efectos de los fármacos , Hígado/metabolismo , Lovastatina/análogos & derivados , Lovastatina/farmacología , Escualeno/metabolismo , Escualeno-Monooxigenasa , Células Tumorales Cultivadas
20.
Diabetes ; 42(10): 1446-53, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8375584

RESUMEN

In the Goto-Kakizaki rat, a new genetic model of NIDDM, insulin response to glucose is selectively impaired. To elucidate the mechanism of this abnormality, we studied the properties of ATP-sensitive K+ channels, the inhibition of which is a key step of insulin secretion induced by fuel substrates, using the patch-clamp technique. The glucose-sensitivity of KATP channels was considerably reduced in GK rats. However, the inhibitory effects of ATP on channel activity and unitary conductance were not significantly different between control and GK rats. Thus, it appears that the impaired insulinotropic action of glucose in beta-cells of GK rats is attributable to insufficient closure of the KATP channels, probably because of deficient ATP production by impaired glucose metabolism. KATP-channel activities in both control and diabetic beta-cells were found to be equally suppressed by glyceraldehyde and 2-ketoisocaproate. These results strongly suggest that the step responsible for the metabolic dysfunction of diabetic beta-cells is located within the glycolytic pathway before glyceraldehyde-3-phosphate or in the glycerol phosphate shuttle.


Asunto(s)
Adenosina Trifosfato/farmacología , Diabetes Mellitus Tipo 2/fisiopatología , Glucosa/farmacología , Islotes Pancreáticos/fisiopatología , Canales de Potasio/fisiología , Animales , Glucemia/análisis , Peso Corporal/efectos de los fármacos , Errores Innatos del Metabolismo de los Carbohidratos/genética , Diabetes Mellitus Tipo 2/enzimología , Diabetes Mellitus Tipo 2/genética , Modelos Animales de Enfermedad , Glucoquinasa/análisis , Gliceraldehído/farmacología , Insulina/sangre , Islotes Pancreáticos/enzimología , Islotes Pancreáticos/patología , Cetoácidos/farmacología , Masculino , Canales de Potasio/efectos de los fármacos , Ratas , Ratas Wistar
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