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1.
Cell Calcium ; 10(1): 29-35, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2543505

RESUMEN

The effects of platelet-derived growth factor (PDGF) on the intracellular free Ca2+ concentration [( Ca2+]i) in chondrocytes were studied with a fluorescent Ca2+ indicator, fura 2, and compared with the effects of PDGF on mitogenesis and proteoglycan synthesis. PDGF evoked phasic and then tonic increase in [Ca2+]i dose-dependently in quiescent cultures of chondrocytes, and it also stimulated both DNA and proteoglycan syntheses dose-dependently similar to somatomedins. Suramin, which inhibits the interaction of PDGF with its receptors, caused dose-dependent inhibition of both the PDGF-evoked increase in [Ca2+]i and stimulation of DNA synthesis by PDGF. However, suramin rather enhanced the proteoglycan synthesis induced by PDGF without affecting the basal level of proteoglycan synthesis directly. These results suggest that [Ca2+]i may be an important signal for the action of PDGF on cell proliferation in chondrocytes, and that the initial signal for proteoglycan synthesis is different from that for DNA synthesis induced by PDGF after the activation of PDGF receptor.


Asunto(s)
Calcio/metabolismo , Cartílago/citología , Mitosis/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteoglicanos/biosíntesis , Suramina/farmacología , Animales , Benzofuranos , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Citofotometría , Fura-2 , Masculino , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Conejos , Receptores de Superficie Celular/metabolismo , Receptores del Factor de Crecimiento Derivado de Plaquetas
2.
Cell Calcium ; 8(5): 397-410, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2962738

RESUMEN

The effects of the antianginal drugs nitroglycerin, nicorandil, diltiazem, verapamil and nicardipine on the activity of calcium-stimulated magnesium-dependent ATPase (Ca2+-ATPase) were investigated in the microsomal fraction from porcine coronary artery smooth muscle cells. Two discrete Ca2+-dependent ATPase components were observed: [1] a high affinity component, which was a specific Ca2+-ATPase, [with a half saturation constant for Ca2+ (Km) of 0.44 microM, and maximum velocity (Vmax) of 124.3 pmol of phosphate (Pi) released/micrograms of protein/30 min]: [2] a low affinity component in which Ca2+ could be replaced by Mg2+ without loss of its activity. Nitroglycerin and nicorandil (1 microM and 10 microM) both stimulated the activity of the Ca2+-ATPase significantly [142 +/- 12 (mean +/- standard error), and 137 +/- 10% of the control with nitroglycerin, and 152 +/- 17 and 135 +/- 20% with nicorandil] at a Ca2+ concentration of 0.3 microM. Diltiazem, verapamil and nicardipine did not cause significant stimulation. Nitroglycerin and nicorandil (1 microM), significantly decreased the Km for Ca2+ from the control value of 0.44 +/- 0.06 microM to 0.26 +/- 0.03 and 0.22 +/- 0.03 microM, respectively. Nitroglycerin and nicorandil may dilate coronary arteries by stimulating this Ca2+ extrusion pump enzyme through reduction of intracellular Ca2+ in smooth muscle cells.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , ATPasas Transportadoras de Calcio/metabolismo , Microsomas/enzimología , Músculo Liso Vascular/efectos de los fármacos , Nitratos/farmacología , Vasodilatadores/farmacología , Animales , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/enzimología , Músculo Liso Vascular/enzimología , Porcinos
3.
J Comp Neurol ; 302(4): 715-28, 1990 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-2081815

RESUMEN

The calcium ion plays an important role in some critical developmental events in the nervous system, such as neurulation and neurite elongation. Therefore, as the intracellular calcium-binding proteins calbindin-D28k (CaB) and parvalbumin (PV) may be expressed in these developmental events. Accordingly, the ontological expression of CaB and PV was examined immunocytochemically in the spinal cord and dorsal root ganglia (DRG) of the rat, in order to evaluate the relationship between CaB and PV expression, and other important developmental events. During the ontogenesis of the spinal cord, the CaB-like immunoreactivity was mainly observed in the cell somata. The immunoreactive cells in the ventral horn of the cervical and thoracic, lumbar, and sacral segments first appeared at embryonic day (E)-12, E-13, and E-14, respectively. However, these cells were not detected in the intermediate gray matter of the same segments at E-14, E-15, and E-16, respectively, and in the dorsal horn at E-14-E-15, E-16, and E-17, respectively. The peak of immunoreactive cells, both as to number and intensity, occurred in the perinatal period. However, from postnatal day (P)-14 on, the number and intensity of the positive cells decreased, the adult levels being reached at P-35. The PV-like immunoreactivity was mainly detected in the fibers and punctata during the ontogenesis of the spinal cord. The immunoreactive fibers first appeared on the surface of the dorsal horn in the cervical and thoracic segments at E-14, then entered the dorsal horn at E-15, and reached the intermediate gray matter and ventral horn at E-16. The first appearance of these fibers in the same areas of the lumbar and sacral segments occurred 1 day later than in the cervical and thoracic segments. During the perinatal period, the maximum content of PV-like immunoreactive fibers, together with many punctata, was seen in the gray matter. However, between P-14 and P-17, most of them lost immunoreactivity rapidly, with the exception of the medial region of the intermediate gray matter, where the PV-immunoreactive punctata remained up to the adult stage. In DRG neurons, both CaB and PV was expressed, but in different neurons. Neurons labeled with anti-CaB and anti-PV sera were first detected at E-16 and E-14, respectively. These neurons were large or medium-sized in the prenatal period.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Ganglios Espinales/crecimiento & desarrollo , Parvalbúminas/análisis , Proteína G de Unión al Calcio S100/análisis , Médula Espinal/crecimiento & desarrollo , Animales , Calbindina 1 , Calbindinas , Calcio/metabolismo , Ganglios Espinales/química , Ganglios Espinales/embriología , Regulación de la Expresión Génica , Neuronas/química , Ratas , Ratas Endogámicas , Médula Espinal/química , Médula Espinal/embriología
4.
J Comp Neurol ; 292(2): 193-213, 1990 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-2319009

RESUMEN

Postnatal developmental changes of preproenkephalin (PPE) gene expression in rat brainstem neurons were studied by in situ hybridization histochemistry. On the basis of PPE mRNA expression, brainstem neurons were categorized into three types: 1) type I neurons were characterized by constant or increasing expression of PPE mRNA during postnatal development; 2) type II neurons started to express PPE mRNA several days after birth and continued to do so thereafter; and 3) type III neurons showed transient expression of PPE mRNA or stopped expressing the mRNA during early postnatal development. Type I PPE neurons were observed in diverse brainstem structures including the mesencephalic and pontine central gray matter, various reticular and raphe nuclei, the ventral tegmental area of Tsai, the interpeduncular nucleus, the nucleus of the brachium of the inferior colliculus, the ventral and dorsal tegmental nuclei of Gudden, the sphenoid nucleus, the laterodorsal tegmental nucleus, Barrington's nucleus, the parabrachial region, the lateral lemniscus and its related nuclei, the trapezoid nucleus, the rostral and ventromedial periolivary nuclei, the mesencephalic trigeminal and principal sensory trigeminal nuclei, the locus coeruleus, the subcoeruleus nucleus, the medial and spinal vestibular nuclei, the dorsal and ventral cochlear nuclei, the medial and lateral cerebellar nuclei, the Roller nucleus, and the intermedius nucleus of the medulla. Type II PPE neurons were found in the superior colliculus, the inferior colliculus, the central part of the dorsal tegmental nucleus, and as Golgi neurons in the granular layer of the cerebellum. Type III PPE neurons were located in the substantia nigra, the red nucleus, the superior olive, the motor trigeminal nucleus, the facial nucleus, the inferior olive, the dorsal motor nucleus of the vagus, and the hypoglossal nucleus. Such region-specific expression of the PPE gene during postnatal ontogeny suggests that rat brainstem PPE neurons may be involved in a variety of developmental events, such as cell proliferation, differentiation, and migration.


Asunto(s)
Envejecimiento/metabolismo , Tronco Encefálico/metabolismo , Encefalinas/metabolismo , Regulación de la Expresión Génica , Precursores de Proteínas/metabolismo , ARN Mensajero/metabolismo , Animales , Tronco Encefálico/crecimiento & desarrollo , Encefalinas/fisiología , Masculino , Hibridación de Ácido Nucleico , Precursores de Proteínas/fisiología , Ratas , Ratas Endogámicas
5.
Brain Res Mol Brain Res ; 7(4): 335-45, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2163008

RESUMEN

The localization of gamma-aminobutyric acid-A (GABAA) receptors (GABAA-R) in the lower brainstem of the rat was examined by means of in situ hybridization histochemistry using an oligonucleotide probe to the sequence of the alpha 1 subunit (GABAA-R alpha 1). Strongly labeled neurons were found in the cranial motor nuclei, the dorsal motor nucleus of the vagus, reticular formation (large neurons), lateral vestibular nucleus, dorsal nucleus of the lateral lemniscus, central nucleus of the inferior colliculus, intermediate and white layers of the superior colliculus, red nucleus and substantia nigra. In addition, moderately labeled cells were abundant in the nucleus of the solitary tract, medial and inferior vestibular nuclei, parabrachial area, dorsal and ventral tegmental nuclei of Gudden, central gray matter, ventral nucleus of the lateral lemniscus, and reticular formation (small neurons). This study has therefore revealed some of the target neurons of GABA-containing fibers in the lower brainstem.


Asunto(s)
Tronco Encefálico/metabolismo , ARN Mensajero/genética , Receptores de GABA-A/genética , Animales , Autorradiografía , Tronco Encefálico/citología , Masculino , Hibridación de Ácido Nucleico , Oligonucleótidos/genética , Oligonucleótidos/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas , Receptores de GABA-A/metabolismo
6.
Neurosci Res ; 4(4): 337-41, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2885797

RESUMEN

New Hampshire normal (line 412) and dystrophic (line 413) chickens were treated with central stimulants and central depressants, respectively, once a day from the 2nd to the 10th day after hatching, and effects of the treatment were examined on a number of muscle fibers, areas of muscle fibers, and the coefficient of variation of a muscle on the 13th day. Central depressants, especially phenobarbital, effectively prevented development of the dystrophic symptoms, whereas central stimulants made normal chickens "dystrophic". The righting ability of the dystrophic chickens was normal after treatment with 10 mg/kg of phenobarbital during the early postnatal period from the 2nd to the 28th day after hatching.


Asunto(s)
Distrofia Muscular Animal/tratamiento farmacológico , Fenobarbital/uso terapéutico , Factores de Edad , Animales , Depresores del Sistema Nervioso Central/uso terapéutico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Pollos , Músculos/efectos de los fármacos , Músculos/patología , Distrofia Muscular Animal/patología , Fenitoína/uso terapéutico
7.
Int J Hematol ; 54(3): 213-7, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1660736

RESUMEN

A female patient in whom acute nonlymphocytic leukemia (ANLL, FAB-M6) developed during treatment of hepatocellular carcinoma (HCC) is described. Two years after partial hepatectomy and subsequent chemotherapy, leukemia developed following a 2 month preleukemic stage. Chromosomal analysis revealed an abnormal karyotype, 46,XX,-5, + der(5)t(3;5)(q25;q31). The balanced translocation t(3;5) has been observed in all types of ANLL and MDS except for ANLL M3 subtype. We summarize patients with ANLL M6 and t(3;5).


Asunto(s)
Carcinoma Hepatocelular , Cromosomas Humanos Par 3/ultraestructura , Cromosomas Humanos Par 5/ultraestructura , Leucemia Eritroblástica Aguda/genética , Neoplasias Hepáticas , Neoplasias Primarias Múltiples , Translocación Genética , Aclarubicina/administración & dosificación , Adolescente , Adulto , Anciano , Anemia Refractaria con Exceso de Blastos/complicaciones , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/cirugía , Niño , Citarabina/administración & dosificación , Daunorrubicina/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Hepatectomía , Hepatitis B/complicaciones , Humanos , Leucemia Eritroblástica Aguda/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Mitomicina/uso terapéutico , Recurrencia Local de Neoplasia , Prednisolona/administración & dosificación , Inducción de Remisión
8.
J Virol Methods ; 46(2): 279-85, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8188821

RESUMEN

To detect human cytomegalovirus (HCMV) DNA, filter paper spotted with peripheral blood from newborns 4 to 7 days after birth was dried and subjected to the polymerase chain reaction (PCR) followed by Southern blot hybridization with a nonradioactive oligonucleotide probe. The detection rates were 25.1% in healthy individuals and 33.0% in low body weight neonates weighing not more than 2500 g at birth, most of whom appeared to have been infected transplacentally or by other means within the uterus. HCMV was detected after only heating the dried blood on the filter paper, and may be applied as a screening method for the early diagnosis of HCMV.


Asunto(s)
Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/microbiología , Citomegalovirus/genética , ADN Viral/aislamiento & purificación , Filtración , Papel , Adulto , Southern Blotting , Humanos , Recién Nacido , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad
9.
J Virol Methods ; 44(2-3): 141-54, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8263111

RESUMEN

We report a simple procedure for the detection of Epstein-Barr virus (EBV) by in situ DNA-RNA hybridization with an alkaline phosphatase-linked oligonucleotide probe. EBV-producing cell lines P3HR-1 and Akata were treated with phorbol ester and n-butyrate, and anti-human IgG, respectively. This treatment resulted in highly increased populations of cells with EBV transcripts of the latent membrane protein 1 (LMP1) and envelop glycoprotein gp350/220, but not of EBV-encoded small nuclear RNAs (EBERs). Synthesis of the LMP1 protein, which was encoded by the induced mRNA, was mostly dependent on viral DNA synthesis, as shown by double or single labeling for in situ DNA-DNA hybridization with the oligo-nucleotide probe, and immunoperoxidase staining with a monoclonal antibody against LMP1. In situ hybridization of the null cell line HLN-STL-C established from an adult T-cell leukemia patient showed that 100% of the cells contained both EBERs and LMP1 mRNA and about 0.1% of the cells contained gp350/220 mRNA, indicating that a few of the null cells which carried the EBV genome spontaneously entered the late EBV replication cycle.


Asunto(s)
Linfocitos B/microbiología , Proteínas de la Cápside , Herpesvirus Humano 4/genética , Hibridación in Situ , Linfocitos Nulos/microbiología , Sondas de Oligonucleótidos , ARN Mensajero/análisis , Animales , Antígenos Virales/genética , Secuencia de Bases , Butiratos/farmacología , Línea Celular Transformada , Técnica del Anticuerpo Fluorescente , Regulación Viral de la Expresión Génica/efectos de los fármacos , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/fisiología , Humanos , Técnicas para Inmunoenzimas , Datos de Secuencia Molecular , Oligonucleótidos Antisentido , ARN Mensajero/genética , ARN Viral/análisis , ARN Viral/genética , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas , Proteínas de la Matriz Viral/genética , Replicación Viral/efectos de los fármacos
10.
J Virol Methods ; 37(2): 209-18, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1317879

RESUMEN

The presence of inhibitors in urine interferes with the enzymatic reaction of the polymerase chain reaction (PCR) for detection of human cytomegalovirus (HCMV). To remove inhibitors, HCMV virions in urine were precipitated with polyethylene glycol, or DNA was extracted from urine by the use of glass powder and subjected to PCR followed by Southern blot hybridization with alkaline phosphatase-linked oligonucleotide probes. These simple, rapid methods increased significantly the sensitivity of PCR for detection of HCMV in urine.


Asunto(s)
Citomegalovirus/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Orina/microbiología , Secuencia de Bases , Precipitación Química , ADN Viral/orina , Vidrio , Humanos , Datos de Secuencia Molecular , Polietilenglicoles , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Polvos , Orina/química
11.
Life Sci ; 42(2): 215-23, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2826956

RESUMEN

Cultured vascular smooth muscle cells (VSMC) derived from rat aorta were found to contain a specific receptor for 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Its Kd (5.0 x 10(-11) M) and capacity (22.9 fmol/mg of cytosol protein) for 1,25-(OH)2D3, its sedimentation coefficient on a sucrose density gradient (3.2 S), its relative affinities for various vitamin D3 metabolites [1,25-(OH)2D3 greater than 25-hydroxyvitamin D3 greater than 24,25-dihydroxyvitamin D3 greater than vitamin D3] and its affinity for DNA-cellulose were similar to those reported for the 1,25-(OH)2D3 receptor in other tissues. 1,25-(OH)2D3 at concentrations of more than 10(-10) M caused dose-dependent enhancement of the proliferation of VSMC in DMEM with 10% FCS. 25-Hydroxyvitamin D3 stimulated the proliferation of VSMC only at its highest concentration tested (10(-6) M). These data show that 1,25-(OH)2D3 stimulates the proliferation of VSMC after its binding to a cytoplasmic receptor of the cells in vitro, and support the possibility that VSMC are target cells of the hormone.


Asunto(s)
Calcitriol/metabolismo , Músculo Liso Vascular/metabolismo , Receptores de Esteroides/metabolismo , Animales , Aorta/citología , Aorta/efectos de los fármacos , Aorta/metabolismo , Unión Competitiva , Calcitriol/farmacología , División Celular/efectos de los fármacos , Células Cultivadas , Citosol/metabolismo , Femenino , Cinética , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Ratas , Ratas Endogámicas , Receptores de Calcitriol , Receptores de Esteroides/aislamiento & purificación
12.
Clin Exp Rheumatol ; 10(2): 161-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1324125

RESUMEN

Synovial fluid from 20 patients with rheumatoid arthritis was analyzed to detect human cytomegalovirus (CMV) genomic material using polymerase chain reaction. Of 20 samples tested, 9 were positive for CMV by either ethidium bromide staining or Southern blotting. In contrast, CMV was detected in only 2 of 18 control patients with osteoarthritis. These results suggest an etiologic relationship between CMV and rheumatoid arthritis.


Asunto(s)
Artritis Reumatoide/genética , Citomegalovirus/genética , ADN Viral/análisis , ADN Viral/genética , Líquido Sinovial/química , Adulto , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/complicaciones , Artritis Reumatoide/microbiología , Secuencia de Bases , Southern Blotting , Citomegalovirus/aislamiento & purificación , Infecciones por Citomegalovirus/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Osteoartritis/complicaciones , Osteoartritis/genética , Osteoartritis/microbiología , Reacción en Cadena de la Polimerasa , Líquido Sinovial/microbiología
13.
Clin Nephrol ; 40(1): 7-15, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8395370

RESUMEN

A patient with recurrent renal failure due to massive interstitial nephritis caused by Leu 3a + 3b-positive T-cell infiltration and associated with multiple thromboembolic attacks is reported. He died of gastrointestinal bleeding after treatment with anticancer agents. At autopsy, diffuse necrosis of the bilateral kidneys was noted as well as giant coronary aneurysms filled with thrombus that resembled those seen in Kawasaki disease and multiple old myocardial infarcts were also present. Among the various Epstein-Barr virus (EBV)-specific antibodies, the titers anti-viral capsid antigen (VCA) and anti-early antigen (EBEA) IgG antibody were always very high in contrast to the relatively low titers of anti-EB nuclear antigen (EBNA) antibodies. DNA extracted from kidney tissue obtained at autopsy was analyzed by Southern blot hybridization after the amplification of EBV-specific DNA by the polymerase chain reaction. In situ hybridization of kidney tissue obtained at biopsy was also performed using an enzyme-linked probe derived from the EBV-encoded RNA 1 (EBER1) gene. As a result, the EBV genome was found both at autopsy and in the biopsy tissue, which clearly revealed EBER1 in the interstitial cells. Taking account of the progressive ST-T changes of the electrocardiograms which were normal early in his course, multiple myocardial infarction associating multiple giant aneurysms probably occurred during this disease process. Thus, it could be concluded that chronic active EBV infection contributed massive interstitial nephritis mediated by the activation of Leu 3a + 3b-positive T cells.


Asunto(s)
Aneurisma Coronario/complicaciones , Genoma Viral , Infecciones por Herpesviridae/complicaciones , Herpesvirus Humano 4/genética , Riñón/patología , Síndrome Mucocutáneo Linfonodular , Nefritis Intersticial/microbiología , Adulto , Anticuerpos Antivirales/análisis , Southern Blotting , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Inmunofenotipificación , Hibridación in Situ , Masculino , Nefritis Intersticial/complicaciones , Nefritis Intersticial/patología , Reacción en Cadena de la Polimerasa
14.
Avian Dis ; 36(3): 637-45, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1329711

RESUMEN

Differentiation of oncogenic and nononcogenic strains of Marek's disease virus type 1 (MDV1) was attempted by polymerase chain reaction (PCR) using the primers chosen from the sequence within the long inverted repeats of MDV1 DNA. PCR of the DNAs extracted from oncogenic-strain-infected cells and Marek's disease tumor cell lines produced a major product containing two or three copies of 132-base-pair (bp) repeat units, whereas PCRs of the DNAs extracted from nononcogenic-strain-infected cells yielded amplified products with various sizes corresponding to the number of 132-bp repeat units. The primers chosen from the glycoprotein A genes of MDV1 and herpesvirus of turkeys also were used for determination of their serotype specificity. The PCR procedure was found to be a simple and sensitive procedure for identification of MDV1 and herpesvirus of turkeys and for estimation of oncogenicity of MDV1.


Asunto(s)
ADN Viral/genética , Herpesvirus Gallináceo 2/clasificación , Herpesvirus Gallináceo 2/genética , Reacción en Cadena de la Polimerasa/métodos , Secuencia de Bases , Genes Virales/genética , Herpesvirus Gallináceo 2/aislamiento & purificación , Datos de Secuencia Molecular , Secuencias Repetitivas de Ácidos Nucleicos/genética , Sensibilidad y Especificidad
15.
Jpn J Physiol ; 25(1): 79-91, 1975.
Artículo en Inglés | MEDLINE | ID: mdl-1142569

RESUMEN

Synaptic events in a chloride-deficient condition were studied to elucidate functional aspects of presynaptic inhibitory synapses. The extracellular junctional potentials and nerve terminal potentials were concurrently recorded from a synaptic region. Inhibitory stimulation produced repetitive spikes on the inhibitory nerve terminal and then the excitatory nerve terminal, which resulted in the extracellular excitatory junctional potentials. Excitatory stimulation did not produce repetitive spikes on the inhibitory nerve terminal, indicating one-way signal transmission in this axo-axonal synapse from inhibitory to excitatory axon. The interval required for an inhibitory stimulation to produce the first response in the postsynaptic muscle membrane ranged widely from 10 to 800 msec. When gamma-aminobutyric acid (GABA, 1 times 10-minus 4 M) was added in these experimental conditions, the muscle membrane was transiently depolarized by about 10 mV. The action of GABA mimics that of the neurotransmitter at presynaptic inhibitory synapses. The experimental observations may be well explained by the concept of synapses on synapses, i.e., presynaptic inhibition, where the neurotransmitter may be GABA and chloride ions may be playing essential roles as in the case of postsynaptic inhibition.


Asunto(s)
Axones/fisiología , Inhibición Neural , Unión Neuromuscular/fisiología , Potenciales de Acción , Animales , Astacoidea , Cloruros , Estimulación Eléctrica , Técnicas In Vitro , Ácido gamma-Aminobutírico/farmacología
16.
Jpn J Physiol ; 30(3): 357-63, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7420773

RESUMEN

Intracellular chloride concentration in frog sartorius muscle was determined at 20 degrees C utilizing ionic permeability change of the membrane for an ion-selective electrode. The membrane potential and external potassium concentration relation was obtained with changes in pH. Using the constant field equation with a condition given by the crossing point in the two relations obtained with the two different pH, the intracellular chloride concentration was estimated to be 3.7 +/- 0.18 mM (mean +/- S.E.M.) with a 0.76 of the activity coefficient for chloride in Ringer's solution. The chloride potential (-88.5 +/- 1.26 mV) was significantly positive to the resting potential (-94.8 +/- 1.09 mV), suggesting that a chloride pump may be working in the frog skeletal muscle. The existence of the chloride pump was supported further by the fact that the depolarization induced by the pH increase became smaller with cooling and finally disappeared when cooled below 5 degrees C.


Asunto(s)
Cloruros/metabolismo , Músculos/metabolismo , Animales , Permeabilidad de la Membrana Celular , Cloruros/fisiología , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Membranas Intracelulares/metabolismo , Potenciales de la Membrana , Potasio/fisiología , Ranidae
17.
Rinsho Byori ; 42(9): 966-70, 1994 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-7967122

RESUMEN

We used the PCR method to detect CMV-DNA in serum, urine, and peripheral blood of a patient who had received a renal transplant. A correlation was found between the active stage of the infections and the serum level of CMV-DNA. While no correlation was found in urine or blood. To detect CMV-DNA as early as possible, the serum samples were prepared by glass powder treatment and subjected to PCR followed by nonradioactive DNA hybridization. Moreover, to increase the sensitivity of detection a nested PCR method was employed and we found that the PCR-products were easily detected on the ethidium bromide-stained gel without the following hybridization. Thus, PCR in serum would be useful for rapid diagnosis of the infection and monitoring anti-viral drug therapy.


Asunto(s)
Infecciones por Citomegalovirus/diagnóstico , ADN Viral/sangre , Huésped Inmunocomprometido , Trasplante de Riñón , Adulto , Humanos , Masculino , Reacción en Cadena de la Polimerasa
18.
Nihon Geka Gakkai Zasshi ; 95(4): 282-5, 1994 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-8196595

RESUMEN

A 41-year-old male patient of Budd-Chiari syndrome associated with membranous obstructions of the retrohepatic inferior vena cava and the left hepatic vein was reported. A radical operation was carried out. The retrohepatic inferior vena cava was reconstructed by a ringed EPTFE patch graft after endovenectomy with the aid of extracorporeal circulation for caval and portal bypasses utilizing cold hepatic perfusion. The patient has been doing well 18 months after the operation.


Asunto(s)
Síndrome de Budd-Chiari/cirugía , Circulación Extracorporea , Circulación Hepática , Adulto , Circulación Extracorporea/métodos , Humanos , Masculino , Perfusión
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