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1.
Biochim Biophys Acta ; 799(3): 252-9, 1984 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-6375733

RESUMEN

Two monoclonal antibodies to human and bovine neuron-specific gamma gamma enolase have been produced in the isolated hybrid cell lines, which were obtained by fusion between gamma gamma-immunized mouse spleen cells and mouse myeloma cells (P3-NS-1/1-Ag4-1), followed by a screening procedure with an enzyme immunoassay. The monoclonal antibody to human gamma gamma enolase (E1-G3) and that to bovine gamma gamma enolase (B1-D6) consisted of gamma 2a/kappa and gamma l/kappa immunoglobulin chains, respectively. Both antibodies could bind with the respective antigen with a molar ratio of about 1:1, and were found to be specific for the gamma subunit of enolase, showing reactivities with human gamma gamma and alpha gamma, rat gamma gamma and alpha gamma, and bovine gamma gamma enolases. However, the antibodies did not cross-react with the alpha or beta subunit of human and rat enolase isozymes. Both antibodies could partially inhibit the activity of gamma gamma and alpha gamma enolases. E1-G3 antibody inhibited gamma gamma and alpha gamma enolase activity by 70 and 30%, respectively, and B1-D6 antibody, by 90 and 40%, respectively. Both antibodies had no effect on the activity of alpha alpha and beta beta enolases of human and rat origins. The applicability of E1-G3 and B1-D6 antibodies to the sandwich-type enzyme immunoassay for neuron-specific enolase (enolase gamma subunit) was examined, and it was found that the assay system using E1-G3 and B1-D6 as the labeled antibodies were sufficiently sensitive for the assay of serum neuron-specific enolase concentrations.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Isoenzimas/inmunología , Fosfopiruvato Hidratasa/inmunología , Animales , Especificidad de Anticuerpos , Bovinos , Humanos , Técnicas para Inmunoenzimas , Isoenzimas/antagonistas & inhibidores , Masculino , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Fosfopiruvato Hidratasa/antagonistas & inhibidores
2.
J Am Coll Cardiol ; 21(1): 158-62, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8417058

RESUMEN

OBJECTIVES: The aim of this study was to examine the transformation of coronary artery aneurysms to obstructive lesions and to assess the role of collateral vessels in patients with Kawasaki disease. BACKGROUND: Coronary artery aneurysms, especially giant aneurysms, are known to become obstructive lesions in patients with Kawasaki disease. However, the process of transformation is not yet clear. METHODS: Thirty patients (average age 9.9 years) with obstructive lesions secondary to Kawasaki disease underwent repeated coronary artery angiography and thallium myocardial scintigraphy over a mean period of 7.7 years after the acute onset of Kawasaki disease. RESULTS: In the 27 patients who were enrolled in the acute phase of the disease because of coronary artery aneurysms, the later transformation to obstructive lesions was not significantly different between the 61 large and 6 medium-sized aneurysms. Obstructive transformation of aneurysms was more rapid in the right than in the left coronary artery (p < 0.001). From the last coronary angiogram obtained, the obstructive lesions were classified as localized stenosis > 90% in 10 vessels, occlusions in 6 vessels and segmental stenosis in 26 vessels. Both localized and segmental stenosis occurred significantly more often in the left anterior descending and the right coronary artery than in other vessels (p < 0.05). The incidence of collateral vessels was significantly correlated with a younger age at onset of Kawasaki disease, especially in patients with segmental stenosis (p < 0.001). Collateral vessels did not develop in the presence of localized stenosis regardless of the occurrence of myocardial ischemia. All occluded vessels had collateral development regardless of the presence of myocardial infarction. CONCLUSIONS: The treatment of localized stenosis may play an important role in preventing myocardial infarction in the chronic phase of Kawasaki disease.


Asunto(s)
Circulación Colateral , Aneurisma Coronario/complicaciones , Circulación Coronaria , Enfermedad Coronaria/etiología , Síndrome Mucocutáneo Linfonodular/complicaciones , Enfermedad Aguda , Adolescente , Distribución de Chi-Cuadrado , Niño , Preescolar , Aneurisma Coronario/diagnóstico , Aneurisma Coronario/epidemiología , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Femenino , Corazón/diagnóstico por imagen , Humanos , Incidencia , Masculino , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/epidemiología , Pronóstico , Radioisótopos de Talio , Tomografía Computarizada de Emisión de Fotón Único
3.
J Mol Biol ; 256(5): 897-908, 1996 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8601841

RESUMEN

The three-dimensional structure of Escherichia coli cytosolic cyclophilin A (CyPA) complexed with a tripeptide (succinyl-Ala-Pro-Ala-p-nitroanilide) was refined at 1.8 A resolution by the multiple isomorphous replacement method to a crystallographic R-factor of 17.6%. As in human CyPA, the peptide binding site in E. coli enzyme is in a cleft created on the surface of the upper sheet of two orthogonal beta-sheets. In this cleft, the walls of the hydrophobic pocket are formed by the side-chains of five non-polar residues, Phe48, Met49, Phe107, Leu108, and Try120, with Phe99 at the bottom. When the cis isomer of the tripeptide binds to the enzyme, a cis-proline ring is inserted into the hydrophobic pocket. Since the binding pocket of CyPAs are largely hydrophobic, the cis isomer of a peptide can be bound more firmly than the trans isomer. Distortion of the trans isomer could lead to better binding, but at an energetic cost of the distortion energy. At the periphery of the upper beta-sheet in E. coli CyPA, conformations of loops L1, L3, and L4 and the segment connecting alpha1 and beta3 with deletions or insertions against human CyPA differ significantly from those in human CyPA. The refined model also shows that steric hindrance to attachment of cyclosporin A (CsA) prevents E. coli CyPA forming a complex with CsA. Thus, the extra amino acid residue of E. coli CyPA, polar Gln89, lies along the pathway to the hydrophobic pocket of CyPA and seems to prevent the access hydrophobic part of CsA to the cleft of CyPA.


Asunto(s)
Isomerasas de Aminoácido/genética , Isomerasas de Aminoácido/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Isomerasas de Aminoácido/química , Secuencia de Aminoácidos , Sitios de Unión , Proteínas Portadoras/química , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Oligopéptidos/química , Oligopéptidos/genética , Oligopéptidos/metabolismo , Isomerasa de Peptidilprolil , Prolina/química , Estructura Secundaria de Proteína , Homología de Secuencia de Aminoácido , Estereoisomerismo
4.
J Mol Biol ; 297(3): 791-802, 2000 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-10731429

RESUMEN

Escherichia coli cyclophilin A, a 164 residue globular protein, shows fast and slow phases of refolding kinetics from the urea-induced unfolded state at pH 7.0. Given that the slow phases are independent of the denaturant concentration and may be rate-limited by cis/trans isomerizations of prolyl peptide bonds, the fast phase represents the true folding reaction. The extrapolation of the fast-phase rate constant to 0 M urea indicates that the folding reaction of cyclophilin A is extraordinarily fast and has about 700 s(-1) of the rate constant. Interrupted refolding experiments showed that the protein molecules formed in the fast phase had already been fully folded to the native state. This finding overthrows the accepted view that the fast folding is observed only in small proteins of fewer than 100 amino acid residues. Examination of the X-ray structure of cyclophilin A has shown that this protein has only one unique hydrophobic core (phenylalanine cluster) formed by evolutionarily conserved phenylalanine residues, and suggests that this architecture of the molecule may be responsible for the fast folding behavior.


Asunto(s)
Escherichia coli/enzimología , Isomerasa de Peptidilprolil/química , Isomerasa de Peptidilprolil/metabolismo , Fenilalanina/metabolismo , Pliegue de Proteína , Secuencia de Aminoácidos , Catálisis/efectos de los fármacos , Dicroismo Circular , Secuencia Conservada , Relación Dosis-Respuesta a Droga , Isomerismo , Cinética , Modelos Químicos , Modelos Moleculares , Datos de Secuencia Molecular , Peso Molecular , Fenilalanina/química , Prolina/metabolismo , Conformación Proteica/efectos de los fármacos , Desnaturalización Proteica/efectos de los fármacos , Renaturación de Proteína , Alineación de Secuencia , Termodinámica , Urea/farmacología
5.
J Mol Biol ; 314(4): 839-49, 2001 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-11734001

RESUMEN

Contractility of vascular smooth muscle depends on phosphorylation of myosin light chains, and is modulated by hormonal control of myosin phosphatase activity. Signaling pathways activate kinases such as PKC or Rho-dependent kinases that phosphorylate the myosin phosphatase inhibitor protein called CPI-17. Phosphorylation of CPI-17 at Thr38 enhances its inhibitory potency 1000-fold, creating a molecular on/off switch for regulating contraction. We report the solution NMR structure of the CPI-17 inhibitory domain (residues 35-120), which retains the signature biological properties of the full-length protein. The final ensemble of 20 sets of NMR coordinates overlaid onto their mean structure with r.m.s.d. values of 0.84(+/-0.22) A for the backbone atoms. The protein forms a novel four-helix, V-shaped bundle comprised of a central anti-parallel helix pair (B/C helices) flanked by two large spiral loops formed by the N and C termini that are held together by another anti-parallel helix pair (A/D helices) stabilized by intercalated aromatic and aliphatic side-chains. Chemical shift perturbations indicated that phosphorylation of Thr38 induces a conformational change involving displacement of helix A, without significant movement of the other three helices. This conformational change seems to flex one arm of the molecule, thereby exposing new surfaces of the helix A and the nearby phosphorylation loop to form specific interactions with the catalytic site of the phosphatase. This phosphorylation-dependent conformational change offers new structural insights toward understanding the specificity of CPI-17 for myosin phosphatase and its function as a molecular switch.


Asunto(s)
Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Porcinos , Algoritmos , Animales , Sitios de Unión , Concentración 50 Inhibidora , Modelos Moleculares , Fosfatasa de Miosina de Cadena Ligera , Resonancia Magnética Nuclear Biomolecular , Fosfoproteínas Fosfatasas/metabolismo , Fosforilación , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Soluciones , Relación Estructura-Actividad
6.
Endocrinology ; 124(2): 870-7, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2463906

RESUMEN

Somatomedin/insulin-like growth factor (IGF)-like polypeptides (designated SMP) were purified from the serum-free conditioned medium of cultured rat epithelial-like cells, 18,54-SF. A monoclonal antibody (MAb) was produced against partially purified SMP. The antibody was immunoglobulin G1 relatively specific for multiplication-stimulating activity III-2 (rat IGF-II), with a Kd value of 5.6 X 10(-9) M. The antibody showed 100% cross-reactivity with human IGF-II and 10% cross-reactivity with human IGF-I, but did not cross-react with insulin. For purification of SMP, therefore, immunoaffinity chromatography on Sepharose coupled with the MAb was used besides a procedure including ion exchange chromatography, gel filtration, and reverse phase HPLC. The purified SMP (at least five polypeptides) each gave a single peak on reverse phase HPLC and appeared as a single band with an apparent mol wt of 5000-8000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The major components of SMP (designated HP1-SMP and HP3-SMP), which were purified about 100-fold from conditioned medium, stimulated DNA synthesis in human fibroblasts in culture and sulfation in chick embryonic cartilage in culture. These polypeptides showed almost the same cross-reactivity as multiplication-stimulating activity III-2 on RIA with the MAb. The partial amino acid sequences of HP1- and HP3-SMP were determined, and these polypeptides were identified with rat IGF-II.


Asunto(s)
Anticuerpos Monoclonales , Epítopos/análisis , Factor II del Crecimiento Similar a la Insulina/metabolismo , Somatomedinas/metabolismo , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Línea Celular , Cromatografía de Afinidad , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Epitelio , Factor II del Crecimiento Similar a la Insulina/inmunología , Factor II del Crecimiento Similar a la Insulina/aislamiento & purificación , Radioinmunoensayo , Ratas
7.
Gene ; 164(2): 377-8, 1995 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-7590364

RESUMEN

The cDNA encoding human P5 was cloned and sequenced. The predicted 440-amino-acid (aa) sequence of human P5 contains two thioredoxin-like domains, which are also found in members of the protein disulfide isomerase superfamily. The human and hamster P5 genes reveal 87 and 93% similarity in their nucleotide and deduced aa sequences, respectively.


Asunto(s)
Hominidae/genética , Isomerasas/biosíntesis , Isomerasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , Cricetinae , ADN Complementario , Humanos , Datos de Secuencia Molecular , Proteína Disulfuro Isomerasas , Señales de Clasificación de Proteína/genética , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
8.
FEBS Lett ; 372(2-3): 210-4, 1995 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-7556671

RESUMEN

We isolated the cDNA of a novel protein disulfide isomerase (PDI)-related protein, designated PDIR, from a human placental cDNA library. Deduced from its nucleotide sequence, PDIR has the three CXXC-like motifs (Cys-Ser-Met-Cys, Cys-Gly-His-Cys and Cys-Pro-His-Cys), which are found in proteins within the PDI superfamily and are responsible for oxidoreductase activity. PDIR has a hydrophobic stretch at its amino terminus, which may serve as a signal sequence, and the putative endoplasmic reticulum (ER) retention signal 'Lys-Glu-Glu-Leu' at its carboxy terminus, indicating that PDIR is an ER resident protein. Northern blots showed that PDIR is preferentially expressed in cells actively secreting proteins and that the expression of PDIR is stress-inducible. These results suggested that PDIR has oxidoreductase activity of disulfide bonds against polypeptides and that it acts as a catalyst of protein folding in the lumen of the ER.


Asunto(s)
Isomerasas/metabolismo , Placenta/metabolismo , Proteínas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Femenino , Humanos , Datos de Secuencia Molecular , Embarazo , Proteína Disulfuro Isomerasas , Proteínas/aislamiento & purificación , Alineación de Secuencia
9.
FEBS Lett ; 377(3): 505-11, 1995 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-8549786

RESUMEN

We investigated the effect of protein disulfide isomerase (PDI) on in vivo protein folding of human lysozyme (h-LZM) in a specially constructed yeast coexpression system. Coexpression with PDI increased the amounts of intracellular h-LZM with the native conformation, leading to an increase in h-LZM secretion. The results indicated that PDI is a real catalyst of protein folding in the cell. The secretion of h-LZM increased even when both active sites of PDI were disrupted, suggesting that the effect of PDI resulted from a function other than the formation of disulfide bonds. This is the first finding that PDI without isomerase activity accelerates protein folding in vivo.


Asunto(s)
Isomerasas/metabolismo , Chaperonas Moleculares/metabolismo , Muramidasa/metabolismo , Pliegue de Proteína , Secuencia de Bases , Clonación Molecular , Amplificación de Genes , Vectores Genéticos , Humanos , Isomerasas/genética , Chaperonas Moleculares/genética , Datos de Secuencia Molecular , Muramidasa/genética , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa , Proteína Disulfuro Isomerasas , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
10.
FEBS Lett ; 328(1-2): 203-8, 1993 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-8344427

RESUMEN

A mutant human lysozyme, designated as C77A-a, in which glutathione is bound to Cys95, has been shown to mimic an intermediate in the formation of a disulfide bond during folding of human (h)-lysozyme. Protein disulfide isomerase (PDI), which is believed to catalyze disulfide bond formation and associated protein folding in the endoplasmic reticulum, attacked the glutathionylated h-lysozyme C77A-a to dissociate the glutathione molecule. Structural analyses showed that the protein is folded and that the structure around the disulfide bond, buried in a hydrophobic core, between the protein and the bound glutathione is fairly rigid. Thioredoxin, which has higher reducing activity of protein disulfides than PDI, catalyzed the reduction with lower efficiency. These results strongly suggest that PDI can catalyze the disulfide formation in intermediates with compact structure like the native states in the later step of in vivo protein folding.


Asunto(s)
Glutatión/metabolismo , Isomerasas/metabolismo , Muramidasa/metabolismo , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Cisteína/metabolismo , Disulfuros , Humanos , Oxidación-Reducción , Proteína Disulfuro Isomerasas , Pliegue de Proteína , Estructura Terciaria de Proteína , Especificidad por Sustrato , Tiorredoxinas/metabolismo
11.
J Med Chem ; 40(15): 2386-97, 1997 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-9240353

RESUMEN

The pentapeptide, thymopentin (Arg1-Lys2-Asp3-Val4-Tyr5) is known for its activity as an immunomodulating drug, but with limited half-life in plasma. In this first paper of a series of three studies, the synthesis of analogs stabilized at the peptide bond between the C-terminal amino acids via insertion of a ketomethylene moiety is described. N-Blocked pseudopeptides containing Val(k)Phe, Ala(k)Phe, and Val(k)Val units were prepared and attached to chloromethyl Merrifield resin via the carboxy terminal. Removal of the N-BOC group by trifluoroacetic acid was followed by sequential coupling with N-BOC dipeptides of aspartic acid to yield resin-bound N-BOC pseudotetrapeptides. Removal of N-BOC and coupling with N-BOC-r-N-tosylarginine followed by total cleavage of blocking groups and resin by HF afforded the target pseudopentapeptides. The analogs were found to compete favorably with thymopentin for binding to CEM cells, but binding was reduced by about 20-30% on average. All analogs showed significant enhancement of half-life versus thymopentin in mouse serum, but most showed only modest improvement in human serum. Insertion of proline or norleucine at position 2 in the chain caused a substantial increase in half-life (3-4-fold), while N-methylnorleucine conferred complete stability in the analogs.


Asunto(s)
Adyuvantes Inmunológicos/química , Cetonas/química , Oligopéptidos/química , Timopentina/análogos & derivados , Adyuvantes Inmunológicos/sangre , Adyuvantes Inmunológicos/farmacología , Animales , Línea Celular , Semivida , Humanos , Espectroscopía de Resonancia Magnética , Ratones , Ensayo de Unión Radioligante , Espectrometría de Masa Bombardeada por Átomos Veloces , Relación Estructura-Actividad , Timopentina/sangre , Timopentina/farmacología
12.
J Nucl Med ; 37(8): 1361-4, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8708774

RESUMEN

We encountered a patient with pheochromocytoma associated with a catecholamine-induced cardiomyopathy that developed recurrently bilateral and unilateral pulmonary edema. The diagnosis of pheochromocytoma was made by elevated plasma catecholamine levels and the intense tumor [123I]MIBG uptake and was confirmed at the time of surgery. The patient showed reduced myocardial [123I]MIBG uptake with left ventricular dysfunction, and endomyocardial biopsy findings were consistent with the diagnosis of catecholamine-induced cardiomyopathy. After tumor resection, plasma levels of catecholamine were normalized, and pulmonary edema never recurred, although cardiac dysfunction did not show an improvement on echocardiography. Myocardial and lung [123I]MIBG uptake increased when compared to uptake levels on preoperative scans, but myocardial uptake was still below normal. These findings indicated that over-secreted catecholamines influenced both the heart and lungs. Pheochromocytoma can induce cardiac and lung injuries, and [123I]MIBG scanning may contribute not only to tumor characterization but also to assessing and monitoring the influence of catecholamines on the heart and lungs.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Cardiomiopatías/etiología , Radioisótopos de Yodo , Yodobencenos , Feocromocitoma/diagnóstico por imagen , Edema Pulmonar/etiología , 3-Yodobencilguanidina , Neoplasias de las Glándulas Suprarrenales/complicaciones , Anciano , Cardiomiopatías/diagnóstico por imagen , Medios de Contraste , Epinefrina/sangre , Femenino , Corazón/diagnóstico por imagen , Humanos , Norepinefrina/sangre , Feocromocitoma/complicaciones , Edema Pulmonar/diagnóstico por imagen , Cintigrafía , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Tomografía Computarizada por Rayos X , Ultrasonografía , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología
13.
J Biochem ; 93(5): 1457-60, 1983 May.
Artículo en Inglés | MEDLINE | ID: mdl-6885732

RESUMEN

A mouse hybrid cell line producing an antibody to human nervous system-specific gamma gamma enolase has been isolated by fusions between gamma gamma-immunized mouse spleen cells and mouse myeloma cells (P3-NS-1/1-Ag4-1), followed by a screening procedure with an enzyme immunoassay. This particular cell line (E1-G3) has secreted the antibody bearing gamma 2a/kappa immunoglobulin chains. Specificity of the E1-G3 antibody was tested by immunoprecipitation of enolase activities with anti-mouse IgG, and by use of enzyme immunoassay systems for enolase isozymes which consisted of polyclonal rabbit antibodies. The E1-G3 antibody was found to be specific for the gamma subunit of enolase, showing reactivities with human gamma gamma and alpha gamma enolases, and also with rat gamma gamma enolase. However, the monoclonal antibody did not cross-react with the alpha or beta subunit of human enolase.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Fosfopiruvato Hidratasa/inmunología , Animales , Línea Celular , Hibridomas/metabolismo , Ratones , Mieloma Múltiple , Bazo
14.
J Appl Physiol (1985) ; 77(3): 1333-40, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7836137

RESUMEN

The purpose of the present study was to assess the role of polymorphonuclear leukocyte (neutrophil) elastase in endotoxin-induced acute lung injury in sheep with lung lymph fistula. We studied the effects of ONO-5046, a specific inhibitor of neutrophil elastase, on the lung dysfunction induced by the intravenous infusion of 1 microgram/kg of Escherichia coli endotoxin. Endotoxin alone produced a biphasic response as previously reported. Early (0.5-1 h) after endotoxin, pulmonary arterial pressure increased from 19.5 +/- 0.9 cmH2O at baseline to a peak of 46.8 +/- 2.4 cmH2O (P < 0.05). Pulmonary vascular resistance increased from 3.03 +/- 0.17 cmH2O.l-1.min at baseline to a peak of 9.77 +/- 0.70 cmH2O.l-1.min (P < 0.05). Circulating neutrophils decreased from 7,355 +/- 434/mm3 at baseline to a nadir of 1,762 +/- 32/mm3 (P < 0.05). Thromboxane B2 and 6-ketoprostaglandin F1 alpha concentrations in plasma and lung lymph were significantly increased. Late (3-5 h) after endotoxin, pulmonary arterial pressure and pulmonary vascular resistance returned to baseline levels, but lung lymph flow remained increased from 4.2 +/- 0.3 ml/0.5 h at baseline to 7.3 +/- 0.7 ml/0.5 h (P < 0.05), with a slight increase in lung lymph-to-plasma protein concentration ratio, suggesting increased pulmonary vascular permeability. The histopathological features of the lungs during the early period in sheep treated with endotoxin alone revealed a large increase in neutrophils per 100 alveoli and changes of pulmonary edema such as thickening of the interstitium of the lung and alveolar flooding.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Bacteriemia/fisiopatología , Infecciones por Escherichia coli/fisiopatología , Esterasas/antagonistas & inhibidores , Glicina/análogos & derivados , Enfermedades Pulmonares/patología , Enfermedades Pulmonares/fisiopatología , Neutrófilos/enzimología , Sulfonamidas/farmacología , 6-Cetoprostaglandina F1 alfa/metabolismo , Animales , Bacteriemia/patología , Análisis de los Gases de la Sangre , Endotoxinas/sangre , Infecciones por Escherichia coli/patología , Esterasas/sangre , Glicina/farmacología , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/enzimología , Hipertensión Pulmonar/fisiopatología , Leucocitos/efectos de los fármacos , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/microbiología , Linfa/fisiología , Neutrófilos/efectos de los fármacos , Circulación Pulmonar/efectos de los fármacos , Ovinos , Tromboxano B2/metabolismo
15.
Eur J Pharmacol ; 370(2): 145-51, 1999 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-10323263

RESUMEN

We tested the effect of interferon-alpha on lung function to examine whether interferon-alpha causes some pathophysiological change in the lung. We prepared awake sheep with chronic lung lymph fistula, and measured the pulmonary hemodynamics, lung fluid balance and concentrations of prostanoid products. At 1 h after intravenous interferon-alpha administration (18 x 10(6) I.U.), pulmonary arterial pressure and pulmonary vascular resistance were significantly increased compared to the baseline values. The levels of thromboxane B2 in both plasma and lung lymph were increased concomitant with early elevation on pulmonary arterial pressure. In addition, OKY-046 [sodium-3[4-(1-imidazolylmethyl)phenyl]-2-propenoic acid] (10 mg kg(-1)), a selective thromboxane synthase inhibitor, significantly prevented the interferon-alpha-induced pulmonary hypertension and thromboxane B2 production. While no evidence of increased pulmonary vascular leakage was observed. These findings suggest that a single infusion of interferon-alpha stimulates a thromboxane cascade and causes transient pulmonary hypertension. However, interferon-alpha itself or increased thromboxane A2 might not affect the pulmonary vascular permeability in sheep.


Asunto(s)
Antivirales/farmacología , Hipertensión Pulmonar/inducido químicamente , Interferón-alfa/farmacología , Pulmón/efectos de los fármacos , Tromboxano B2/metabolismo , 6-Cetoprostaglandina F1 alfa/sangre , Análisis de Varianza , Animales , Temperatura Corporal/efectos de los fármacos , Permeabilidad Capilar/efectos de los fármacos , Inhibidores Enzimáticos/uso terapéutico , Hemodinámica/efectos de los fármacos , Hipertensión Pulmonar/prevención & control , Infusiones Intravenosas , Pulmón/fisiopatología , Metacrilatos/uso terapéutico , Ovinos , Tromboxano B2/sangre , Tromboxano-A Sintasa/antagonistas & inhibidores
16.
J Gastroenterol ; 33(1): 112-6, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9497232

RESUMEN

We report a rare case of Churg-Strauss syndrome (CSS) in a 41-year-old Japanese man with a history of middle-age onset of bronchial asthma who had severe abdominal pain. He presented with ileus caused by an annular ulcer of the ileum, attributable to mucosal ischemia resulting from necrotizing vasculitis of the mesenteric artery. He also had marked hypereosinophilia (51.5%), elevated serum IgE levels (34040 IU/ml), and generalized enlargement of the superficial cervical lymph nodes, containing eosinophilic granulomas. A stenotic lesion caused by an annular ulcer in the ileum was found and resected by laparotomy. Microscopic examination of the resected specimen revealed luminal narrowing or occlusion of small arteries in the ulcer base, subserosa, and mesenterium resulting from marked fibrotic intimal thickening with fragmentation or lack of the internal elastic lamina. These findings were diagnosed as vasculitis, scar stage. The postoperative course was uneventful, with the patient receiving a maintenance dose of prednisolone (10-15 mg/day) for 7 years subsequently. We must carefully diagnose and treat patients with middle-age onset asthma, because the symptom may be a lung manifestation of CSS, in which various organs including gastrointestinal tract are involved as a result of systemic necrotizing vasculitis.


Asunto(s)
Síndrome de Churg-Strauss/complicaciones , Enfermedades del Íleon/complicaciones , Enfermedades del Íleon/patología , Íleon/irrigación sanguínea , Obstrucción Intestinal/etiología , Isquemia/complicaciones , Úlcera/complicaciones , Úlcera/patología , Adulto , Asma/complicaciones , Diagnóstico Diferencial , Humanos , Masculino
17.
Sarcoidosis Vasc Diffuse Lung Dis ; 16(1): 62-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10207943

RESUMEN

BACKGROUND AND AIM OF THE WORK: We previously reported the presence of definite morphological alterations in the capillary endothelium of sarcoid lung. The aim of this study was to examine ultrastructural changes and distribution of lipid droplets in the endothelium of lung capillaries of patients with sarcoidosis. METHODS: Tissue specimens were obtained by transbronchial lung biopsy or open lung biopsy from 16 patients with sarcoidosis and 13 controls. Biopsies were evaluated by electron microscopy following lead citrate and uranyl acetate staining. RESULTS: Typical lipid droplets were observed in pulmonary capillaries of 11 out of 16 sarcoid patients (69%); the droplet frequency was higher in sarcoid patients than in control specimens. Lipid droplets were characterized by biphasic density: most droplets contained eccentrically located vacuoles (saturated fatty acids) others were characterized by low density areas (unsaturated fatty acids). Biphasic droplets were covered by large lysosomal granules and were mainly distributed in the endothelium and pericytes. Interestingly, in the latter, vacuoles increased in size while small amounts of lysosomal granules were detectable. CONCLUSION: Our findings suggest that biphasic droplets increase in number in pulmonary capillaries of patients with sarcoidosis with a characteristic distribution pattern from the endothelium to pericytes.


Asunto(s)
Endotelio Vascular/ultraestructura , Metabolismo de los Lípidos , Pulmón/irrigación sanguínea , Sarcoidosis Pulmonar/metabolismo , Adulto , Capilares/metabolismo , Capilares/ultraestructura , Endotelio Vascular/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos Insaturados/metabolismo , Femenino , Humanos , Pulmón/patología , Masculino , Persona de Mediana Edad , Pericitos/citología , Sarcoidosis Pulmonar/patología
18.
Int J Cardiol ; 68(1): 47-56, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10077400

RESUMEN

We studied the effect of intravenous pirenzepine (3 mg) in normal subjects (n=15, 43+/-16 years old) and in patients with chronic heart failure (n=15, 61+/-12 years old) to assess the effect of low-dose pirenzepine on vagal activity. R-R intervals and the standard deviations, low-frequency power (LF: ln ms2, 0.04-0.15 Hz), high-frequency power (HF: ln ms2, 0.15-0.40 Hz) and the ratio of low- to high-frequency power (LF/HF ratio) were measured 10 min before and after pirenzepine using a Holter analysis system. Pirenzepine was found to cause a significant increase in the R-R interval from 903+/-112 to 956+/-129 ms in the control group (P<0.0001) and from 927+/-141 to 958+/-168 ms in patients with chronic heart failure (P<0.01). Pirenzepine also increased HF significantly from 4.29+/-0.32 to 5.16+/-0.38 ln ms2 in the control group (P<0.0001) and from 4.04+/-0.16 to 4.48+/-0.24 ln ms2 in the chronic heart failure group (P<0.05). Pirenzepine did not significantly alter the LF/HF ratio in either group. We emphasize that pirenzepine appears to have a vagoinimetic effect in patients with chronic heart failure and that it may be useful for augmenting vagal control of the heart in some patients with chronic heart failure.


Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Frecuencia Cardíaca/efectos de los fármacos , Parasimpatolíticos/administración & dosificación , Pirenzepina/administración & dosificación , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Enfermedad Crónica , Ecocardiografía , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Parasimpatolíticos/sangre , Pirenzepina/sangre , Radioinmunoensayo , Nervio Vago/efectos de los fármacos
19.
J Antibiot (Tokyo) ; 41(12): 1795-811, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3209474

RESUMEN

A series of 7 beta-[2-(hetero aromatic methoxyimino)-2-(2-aminothiazol-4-yl)acetamido]- cephalosporins have been synthesized and bacteriologically evaluated. Several substances in this series showed exceptional in vitro activity, especially those with a five-membered hetero aromatic substituent moiety at the 7-position and a quaternary ammonium group as the 3-function of the cephem nucleus. The most active derivative, 7 beta-[2-(imidazol-4-ylmethoxyimino)-2-(2-aminothiazol-4-yl)a cetamido]-3-(pyridiniomethyl)ceph-3-em-4-carboxylate (13a) was the most evenly balanced with respect to activity against Gram-positive and Gram-negative bacteria. Furthermore, 13 was stable to various types of beta-lactamases and had high affinities for penicillin binding protein-3 and -1Bs of both Escherichia coli and Pseudomonas aeruginosa.


Asunto(s)
Cefalosporinas/síntesis química , Bacterias/efectos de los fármacos , Cefalosporinas/farmacología , Estabilidad de Medicamentos , Relación Estructura-Actividad
20.
J Antibiot (Tokyo) ; 40(1): 43-8, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3558117

RESUMEN

A series of potent antimicrobial agents have been prepared. These derivatives are cephalosporins carrying a pyridine ring substituted with a heterocycle in the C-3 position. Some of them showed excellent activity not only against Gram-negative organisms including Pseudomonas aeruginosa but also against Gram-positive ones. In view of their biological and physico-chemical properties, 7 beta-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-[4-(2 or 5-oxazolyl)-1-pyridinium]methyl-3-cephem-4-carboxylate 8f (DQ-2522) and 8g (DQ-2556) were chosen as candidates for further evaluation.


Asunto(s)
Cefalosporinas/síntesis química , Compuestos de Piridinio/síntesis química , Cefalosporinas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Indicadores y Reactivos , Pruebas de Sensibilidad Microbiana , Compuestos de Piridinio/farmacología , Relación Estructura-Actividad
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