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1.
J Intellect Disabil Res ; 65(6): 601-607, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33694205

RESUMEN

BACKGROUND: Cornelia de Lange syndrsome (CdLS) is a rare genetic syndrome with notable impaired expressive communication characterised by reduced spoken language. We examined gesture use to refine the description of expressive communication impairments in CdLS. METHODS: During conversations, we compared gesture use in people with CdLS to peers with Down syndrome (DS) matched for receptive language and adaptive ability, and typically developing (TD) individuals of similar chronological age. RESULTS: As anticipated the DS and CdLS groups used fewer words during conversation than TD peers (P < .001). However, the CdLS group used twice the number of gestures per 100 words compared with the DS and TD groups (P = .003). CONCLUSIONS: Individuals with CdLS have a significantly higher gesture rate than expected given their level of intellectual disability and chronological age. This result indicates the cause of reduced use of spoken language does not extend to all forms of expressive communication.


Asunto(s)
Síndrome de Cornelia de Lange , Síndrome de Down , Discapacidad Intelectual , Síndrome de Cornelia de Lange/genética , Gestos , Humanos , Habla
2.
Am J Transplant ; 13(8): 2154-60, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23746308

RESUMEN

Pancreatic islet transplantation is an attractive therapy for the treatment of insulin-dependent diabetes mellitus. However, the low efficiency of this procedure necessitating sequential transplantations of islets with the use of 2-3 donors for a single recipient, mainly due to the early loss of transplanted islets, hampers its clinical application. Previously, we have shown in mice that a large amount of HMGB1 is released from islets soon after their transplantation and that this triggers innate immune rejection with activation of DC, NKT cells and neutrophils to produce IFN-γ, ultimately leading to the early loss of transplanted islets. Thus, HMGB1 release plays an initial pivotal role in this process; however, its mechanism remains unclear. Here we demonstrate that release of HMGB1 from transplanted islets is due to hypoxic damage resulting from Ca(2+) influx into ß cells through the Na(+) /Ca(2+) exchanger (NCX). Moreover, the hypoxia-induced ß cell damage was prevented by pretreatment with an NCX-specific inhibitor prior to transplantation, resulting in protection and long-term survival of transplanted mouse and human islets when grafted into mice. These findings suggest a novel strategy with potentially great impact to improve the efficiency of islet transplantation in clinical settings by targeting donor islets rather than recipients.


Asunto(s)
Compuestos de Anilina/farmacología , Diabetes Mellitus Experimental/prevención & control , Diabetes Mellitus Tipo 1/inmunología , Rechazo de Injerto/inmunología , Trasplante de Islotes Pancreáticos/inmunología , Islotes Pancreáticos/inmunología , Éteres Fenílicos/farmacología , Intercambiador de Sodio-Calcio/antagonistas & inhibidores , Animales , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/inmunología , Citometría de Flujo , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/metabolismo , Proteína HMGB1/metabolismo , Humanos , Hipoxia/metabolismo , Hipoxia/patología , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Intercambiador de Sodio-Calcio/metabolismo
3.
Nat Med ; 8(11): 1288-95, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12368907

RESUMEN

Adiponectin (Ad) is a hormone secreted by adipocytes that regulates energy homeostasis and glucose and lipid metabolism. However, the signaling pathways that mediate the metabolic effects of Ad remain poorly identified. Here we show that phosphorylation and activation of the 5'-AMP-activated protein kinase (AMPK) are stimulated with globular and full-length Ad in skeletal muscle and only with full-length Ad in the liver. In parallel with its activation of AMPK, Ad stimulates phosphorylation of acetyl coenzyme A carboxylase (ACC), fatty-acid oxidation, glucose uptake and lactate production in myocytes, phosphorylation of ACC and reduction of molecules involved in gluconeogenesis in the liver, and reduction of glucose levels in vivo. Blocking AMPK activation by dominant-negative mutant inhibits each of these effects, indicating that stimulation of glucose utilization and fatty-acid oxidation by Ad occurs through activation of AMPK. Our data may provide a novel paradigm that an adipocyte-derived antidiabetic hormone, Ad, activates AMPK, thereby directly regulating glucose metabolism and insulin sensitivity in vitro and in vivo.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Péptidos y Proteínas de Señalización Intercelular , Proteínas/fisiología , Acetil-CoA Carboxilasa/metabolismo , Adiponectina , Animales , Activación Enzimática , Hepatocitos/enzimología , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/enzimología , Músculo Esquelético/metabolismo , Oxidación-Reducción , Fosforilación
4.
Artículo en Inglés | MEDLINE | ID: mdl-33301406

RESUMEN

OBJECTIVE: To clarify whether there are any muscle synergy changes in individuals with knee osteoarthritis, and to determine whether muscle synergy analysis could be applied to other musculoskeletal diseases. METHODS: Subjects in this study included 11 young controls (YC), 10 elderly controls (EC), and 10 knee osteoarthritis patients (KOA). Gait was assessed on a split-belt treadmill at 3 km/h. A non-negative matrix factorization (NNMF) was applied to the electromyogram data matrix to extract muscle synergies. To assess the similarity of each module, we performed the NNMF analysis assuming four modules for all of the participants. Further, we calculated joint angles to compare the kinematic data between the module groups. RESULTS: The number of muscle modules was significantly lower in the EC (2-3) and KOA (2-3) groups than in the YC group (3-4), which reflects the merging of late swing and early stance modules. The EC and KOA groups also showed greater knee flexion angles in the early stance phase. Contrarily, by focusing on the module structure, we found that the merging of early and late stance modules is characteristic in KOA. CONCLUSION: The lower number of modules in the EC and KOA groups was due to the muscle co-contraction with increased knee flexion angle. Contrarily, the merging of early and late stance modules are modular structures specific to KOA and may be biomarkers for detecting KOA. SIGNIFICANCE: Describing the changes in multiple muscle control associated with musculoskeletal degeneration can serve as a fundamental biomarker in joint disease.


Asunto(s)
Osteoartritis de la Rodilla , Anciano , Fenómenos Biomecánicos , Marcha , Humanos , Articulación de la Rodilla , Músculos
5.
J Int Soc Sports Nutr ; 17(1): 53, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33176796

RESUMEN

BACKGROUND: Vitamin D contributes to the optimal functioning of muscles. This study was designed to determine the modulating effect of vitamin D supplementation on the degree of muscle cell damage caused by eccentric exercise in young men. METHODS: 60 male volunteers (20-24 years old) taking part in this study were divided in two groups - with suboptimal (S) and optimal (O;) 25(OH)D plasma levels. These groups were randomly subdivided into groups with vitamin D supplementation (experimental: SE and OE) and controls (SC and OC). Before the supplementation (Test I) and after 3 months (Test II), participants were subjected to two rounds of eccentric exercise tests on a declined treadmill (running speed corresponded 60% VO2peak determined in each subject in incremental exercise test). During each test, blood samples used for determination of 25(OH)D, Il-1ß, myoglobin (Mb) levels and CK, LDH activity were taken at three timepoints: before the test, 1 h and 24 h after it ended. After distribution normality testing (Saphiro-Wilk test), statistical analyses were performed. Non-parametric: Kruskal-Wallis test and the Wilcoxon test were applied, and the Dunn-Bonferroni test as a post-hoc test. RESULTS: In all groups, after 3 months, higher concentrations of 25(OH)D were indicated (SE p = 0.005; SC p = 0.018; OE p = 0.018; OC p = 0.028). SE and SC groups showed higher baseline concentrations of Il-1ß and significantly higher concentrations of this interleukin after 1 h compared to groups with an optimal 25(OH)D level. After supplementation, the SE group reacted with a similar jump in concentration of Il-1ß as the OC and OE groups. The change after 1 h after exercise in Test II was significantly different from that from Test I (p = 0.047) in SE group. Lower Mb concentrations indicated 1 h after exercise in Test II for SC and SE groups were indicated. CK activity did not differentiate the studied groups. Plasma calcium and phosphate disorders were also not indicated. CONCLUSIONS: The study has shown that vitamin D doses determined from the plasma concentration of 25(OH)D of individuals to match their specific needs can significantly reduce muscle cell damage induced by eccentric exercise.


Asunto(s)
Suplementos Dietéticos , Ejercicio Físico/fisiología , Fibras Musculares Esqueléticas/metabolismo , Vitamina D/administración & dosificación , 25-Hidroxivitamina D 2/sangre , Índice de Masa Corporal , Calcio/sangre , Creatina Quinasa/sangre , Prueba de Esfuerzo , Humanos , Hidroliasas/sangre , Interleucina-1beta/sangre , Masculino , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/patología , Mioglobina/sangre , Fosfatos/sangre , Adulto Joven
6.
Br J Oral Maxillofac Surg ; 58(1): 57-61, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31718918

RESUMEN

We aimed to compare the postoperative stability of conventional bimaxillary surgery (with bilateral sagittal split osteotomy) with that of maxillary impaction surgery (with mandibular autorotation without bilateral sagittal split osteotomy) in patients with skeletal class II retrognathia. Patients were assigned to have conventional bimaxillary surgery (conventional group, n=6) or mandibular autorotation (experimental group, n=7). Measurements were made using serial lateral cephalometric radiographs taken immediately preoperatively (T0), immediately postoperatively (T1), and one year later (T2) to assess the variation in operative change (T1-T0) and relapse (T2-T1). There was no significant difference in median (range) surgical change in the anterior movement at point B (conventional group, 4.5 (3.0-11.0) mm; experimental group 4.1 (2.1-6.4) mm). However, there was a significant difference in median (range) surgical posterior movement relapse at point B (conventional group -1.7 (-2.3 to -0.5) mm; experimental group -0.6 (-1.0 to 1.0) mm; p=0.032). Mandibular advancement with mandibular autorotation is therefore a more stable procedure than mandibular advancement with bilateral sagittal split osteotomy in patients with skeletal class II retrognathia.


Asunto(s)
Retrognatismo , Diente Impactado , Cefalometría , Estudios de Seguimiento , Humanos , Mandíbula , Avance Mandibular , Maxilar , Osteotomía Le Fort , Osteotomía Sagital de Rama Mandibular , Recurrencia
7.
J Neurosci Res ; 87(4): 906-17, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18855935

RESUMEN

We investigated the expression of Na(+)/Ca(2+) exchanger (NCX) and the functional role of NCX in retinal damage by using NCX1-heterozygous deficient mice (NCX1(+/-)) and SEA0400 (2-[4-[(2,5-difluorophenyl)methoxy] phenoxy]-5-ethoxyaniline), a selective NCX inhibitor in vivo. We also examined the role of NCX in oxygen-glucose deprivation (OGD) stress with a retinal ganglion cell line (RGC-5) cell culture in vitro. The expression of NCX1 was confirmed and entirely localized in retina by immunoblotting and immunohistochemistry, respectively. NCX1(+/-) mice possessed significant protection against retinal damage induced by intravitreal injection of N-methyl-D-aspartate (NMDA). SEA0400 at 3 and 10 mg/kg significantly reduced NMDA- or high intraocular pressure-induced retinal cell damage in mice. Furthermore, SEA0400 reduced the number of TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling)-positive cells and the expression of phosphorylated mitogen-activated protein kinases (ERK1/2, JNK, p38) induced by NMDA injection. In RGC-5, SEA0400 at 0.3 and 1 microM significantly inhibited OGD-induced cell damage. OGD-induced cell damage was aggravated by ouabain (a Na(+),K(+)-ATPase inhibitor) at 100 microM, and this increased damage was significantly reduced by SEA0400 at 1 microM. In conclusion, these results suggest that NCX1 may play a role in retinal cell death induced by NMDA and ischemia-reperfusion.


Asunto(s)
N-Metilaspartato/toxicidad , Daño por Reperfusión/fisiopatología , Retina/citología , Células Ganglionares de la Retina/fisiología , Neuronas Retinianas/fisiología , Intercambiador de Sodio-Calcio/metabolismo , Compuestos de Anilina/farmacología , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Inhibidores Enzimáticos/farmacología , Etiquetado Corte-Fin in Situ , Presión Intraocular/fisiología , Ionomicina/toxicidad , Masculino , Ratones , Ratones Transgénicos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fármacos Neuroprotectores/farmacología , Neurotoxinas/farmacología , Ouabaína/farmacología , Éteres Fenílicos/farmacología , Ratas , Retina/efectos de los fármacos , Intercambiador de Sodio-Calcio/antagonistas & inhibidores , Intercambiador de Sodio-Calcio/genética , Estrés Fisiológico , Tapsigargina/toxicidad
8.
Appl Microbiol Biotechnol ; 80(4): 597-604, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18584170

RESUMEN

The gene encoding NADP(+)-dependent L-1-amino-2-propanol dehydrogenase (AADH) of Rhodococcus erythropolis MAK154 was cloned and sequenced. A 780-bp nucleotide fragment was confirmed to be the gene encoding AADH by agreement of the N-terminal and internal amino acid sequences of the purified AADH. The gene (aadh) codes a total of 259 amino acid residues, and the deduced amino acid sequence shows similarity to several short-chain dehydrogenase/reductase family proteins. An expression vector, pKKAADH, which contains the full length aadh was constructed. Escherichia coli cells possessing pKKAADH exhibited a 10.4-fold increase in specific activity as to catalysis of the reduction of (S)-1-phenyl-2-methylaminopropan-1-one (MAK), as compared with that of R. erythropolis MAK154 induced by 1-amino-2-propanol (1 mg/ml). Coexpression of aadh with a cofactor regeneration enzyme (glucose dehydrogenase) gene was also performed, and a system for sufficient production of d-pseudoephedrine from racemic MAK was constructed.


Asunto(s)
Adamantano/análogos & derivados , Oxidorreductasas de Alcohol/genética , Proteínas Bacterianas/genética , Clonación Molecular , Expresión Génica , Rhodococcus/enzimología , Adamantano/metabolismo , Oxidorreductasas de Alcohol/metabolismo , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Glucosa 1-Deshidrogenasa/genética , Glucosa 1-Deshidrogenasa/metabolismo , Datos de Secuencia Molecular
9.
Br J Pharmacol ; 150(4): 434-44, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17220909

RESUMEN

BACKGROUND AND PURPOSE: Although vascular smooth muscle cells are known to express the Na+-Ca2+ exchanger (NCX), its functional role has remained unclear, mainly because of its relatively low expression. We thus investigated the involvement of NCX in the mechanism for the forskolin-induced vaso-relaxation, using wild type (WT) and transgenic (TG) mice that specifically over-express NCX1.3 in smooth muscle. EXPERIMENTAL APPROACH: We examined the relaxing effect of forskolin during the pre-contraction induced by 100 nM U46619, a thromboxane A2 analogue in the mouse isolated thoracic aorta. We also measured the intracellular Ca2+ concentration ([Ca2+]i) in fura-PE3-loaded aortic strips. KEY RESULTS: The forskolin-induced decreases in [Ca2+]i and tension were much greater in aortas from TG mice than in those from WT mice. In a low Na+ solution, forskolin-induced decreases in [Ca2+]i and tension were greatly inhibited in both groups of aortas. In WT aortas, the presence of 100 nM SEA0400, an NCX inhibitor, had only a little effect on the forskolin-induced decreases in [Ca2+]i, but inhibited the forskolin-induced relaxation. However, in TG aortas, the presence of SEA0400 greatly inhibited the forskolin-induced decreases in [Ca2+]i and tension. CONCLUSIONS AND IMPLICATIONS: The NCX was involved in the forskolin-induced reduction of [Ca2+]i and tension in the mouse thoracic aorta. Measurement of [Ca2+]i and tension in aortas of the TG mouse is thus considered to be a useful tool for evaluating the role of NCX in vascular tissue.


Asunto(s)
AMP Cíclico/fisiología , Músculo Liso Vascular/fisiología , Intercambiador de Sodio-Calcio/fisiología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Compuestos de Anilina/farmacología , Animales , Aorta/citología , Aorta/efectos de los fármacos , Aorta Torácica/citología , Aorta Torácica/efectos de los fármacos , Calcio/metabolismo , Colforsina/antagonistas & inhibidores , Colforsina/farmacología , Dinoprost/farmacología , Perros , Colorantes Fluorescentes , Fluorometría , Fura-2/análogos & derivados , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Relajación Muscular/fisiología , Éteres Fenílicos/farmacología , Sodio/fisiología , Intercambiador de Sodio-Calcio/genética , Vasoconstrictores/farmacología
10.
Rev Sci Instrum ; 78(1): 013305, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17503916

RESUMEN

An electron gun constructed using carbon-nanofiber (CNF) emitters and an electrostatic Einzel lens system has been characterized for the development of a high-resolution x-ray source. The CNFs used were grown on tungsten and palladium tips by plasma-enhanced chemical-vapor deposition. Electron beams with the energies of 10

Asunto(s)
Electrones , Nanotubos de Carbono , Radiografía , Electricidad Estática
11.
Structure ; 7(1): 25-34, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10368270

RESUMEN

BACKGROUND: Catechol dioxygenases catalyze the ring cleavage of catechol and its derivatives in either an intradiol or extradiol manner. These enzymes have a key role in the degradation of aromatic molecules in the environment by soil bacteria. Catechol 2, 3-dioxygenase catalyzes the incorporation of dioxygen into catechol and the extradiol ring cleavage to form 2-hydroxymuconate semialdehyde. Catechol 2,3-dioxygenase (metapyrocatechase, MPC) from Pseudomonas putida mt-2 was the first extradiol dioxygenase to be obtained in a pure form and has been studied extensively. The lack of an MPC structure has hampered the understanding of the general mechanism of extradiol dioxygenases. RESULTS: The three-dimensional structure of MPC has been determined at 2.8 A resolution by the multiple isomorphous replacement method. The enzyme is a homotetramer with each subunit folded into two similar domains. The structure of the MPC subunit resembles that of 2,3-dihydroxybiphenyl 1,2-dioxygenase, although there is low amino acid sequence identity between these enzymes. The active-site structure reveals a distorted tetrahedral Fe(II) site with three endogenous ligands (His153, His214 and Glu265), and an additional molecule that is most probably acetone. CONCLUSIONS: The present structure of MPC, combined with those of two 2,3-dihydroxybiphenyl 1,2-dioxygenases, reveals a conserved core region of the active site comprising three Fe(II) ligands (His153, His214 and Glu265), one tyrosine (Tyr255) and two histidine (His199 and His246) residues. The results suggest that extradiol dioxygenases employ a common mechanism to recognize the catechol ring moiety of various substrates and to activate dioxygen. One of the conserved histidine residues (His199) seems to have important roles in the catalytic cycle.


Asunto(s)
Dioxigenasas , Oxigenasas/química , Pseudomonas putida/enzimología , Secuencia de Aminoácidos , Sitios de Unión , Catecol 2,3-Dioxigenasa , Cristalización , Cristalografía por Rayos X , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Alineación de Secuencia , Homología de Secuencia de Aminoácido
12.
Neurogastroenterol Motil ; 28(6): 827-36, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26787195

RESUMEN

BACKGROUND: For the contraction and relaxation of gastric smooth muscles to occur, the intracellular Ca(2+) concentration must be increased and decreased, respectively. The Na(+) /Ca(2+) exchanger (NCX) is a plasma membrane transporter that is involved in regulating intracellular Ca(2+) concentrations. METHODS: To determine the role of NCX in gastrointestinal tissues, we examined electric field stimulation (EFS)-induced relaxations in the circular muscles of the gastric fundus in NCX1 and NCX2 heterozygote knockout mice (HET). KEY RESULTS: The myenteric plexus layers and the longitudinal and circular muscle layers in the gastric fundus of wild-type mice (WT) were strongly immunoreactive to NCX1 and NCX2. EFS induced a transient relaxation that was apparent during the stimulus and a sustained relaxation that persisted after the end of the stimulus. The amplitudes of EFS-induced transient relaxation and sustained relaxation were greater in NCX1 HET and NCX2 HET than in WT. When an inhibitor of nitric oxide synthase was added following the EFS, neither NCX1 HET nor NCX2 HET exhibited transient relaxation, similar to WT. Furthermore, when a PACAP antagonist was added following the EFS, sustained relaxation in NCX1 HET and NCX2 HET was not observed, similar to WT. Next, we examined the effect of NCX heterozygous deficiency on relaxation in response to NO and PACAP in smooth muscles. The magnitude of NOR-1- and PACAP-induced relaxations in NCX1 HET and NCX2 HET was similar to that of WT. CONCLUSIONS & INFERENCES: In this study, we demonstrate that NCX1 and NCX2 expressed in neurons regulate the motility in the gastric fundus.


Asunto(s)
Fundus Gástrico/fisiología , Tránsito Gastrointestinal/fisiología , Heterocigoto , Relajación Muscular/fisiología , Intercambiador de Sodio-Calcio/biosíntesis , Animales , Motilidad Gastrointestinal/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Técnicas de Cultivo de Órganos , Intercambiador de Sodio-Calcio/genética
13.
Hypertension ; 24(2): 227-33, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8039848

RESUMEN

We investigated the intrarenal conversion of big endothelin-1 (ET-1) to ET-1 in the isolated perfused rat kidney. Big ET-1 caused a concentration-dependent increase in perfusion pressure, and the pressor molar potency of the peptide was 50-fold less than that of ET-1. The big ET-1 (2 x 10(-8) mol/L)-induced pressor action was accompanied by increases in immunoreactive endothelin levels in both the perfusate and renal tissues. Phosphoramidon (10(-4) mol/L), a metalloproteinase inhibitor, significantly suppressed the big ET-1-induced pressor action and the accumulation of immunoreactive endothelin in renal tissues. On the other hand, phosphoramidon slightly but significantly sustained the ET-1-induced pressor effect. The effect of kelatorphan (10(-4) mol/L), a specific inhibitor of neutral endopeptidase 24.11, on the ET-1-induced pressor effect was the same as that seen with phosphoramidon. When ET-1 was exogenously added to the perfusate, phosphoramidon or kelatorphan significantly increased the immunoreactive endothelin levels in renal tissues after perfusion, without affecting the disappearance rate of immunoreactive endothelin from the perfusate. Therefore, the phosphoramidon-sensitive ET-1-converting enzyme in the kidney seems to contribute to the functional local conversion of big ET-1 to ET-1, and neutral endopeptidase 24.11 may be responsible for the proteolytic degradation of ET-1 in the kidney. In addition, immunoreactive endothelin levels in renal tissues but not in the perfusate can account for the functional conversion of big ET-1 to ET-1 and for the local proteolytic degradation of ET-1 in the kidney.


Asunto(s)
Endotelinas/metabolismo , Glicopéptidos/farmacología , Riñón/metabolismo , Neprilisina/antagonistas & inhibidores , Animales , Ácido Aspártico Endopeptidasas/fisiología , Presión Sanguínea/efectos de los fármacos , Enzimas Convertidoras de Endotelina , Endotelinas/farmacología , Masculino , Metaloendopeptidasas , Perfusión , Ratas , Ratas Sprague-Dawley
14.
J Med Chem ; 41(4): 489-502, 1998 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-9484499

RESUMEN

Based on the lead tetrapeptide RGDF, two possible non-peptide glycoprotein (GP) IIb-IIIa antagonists possessing an (S)-2-oxopiperazine-3-acetic acid moiety as a scaffold incorporating the indispensable Asp fragment were prepared, and (S)-4-[[trans-[4-(guanidinomethyl)-cyclohexyl]carbonyl]glycyl]-2- oxopiperazine-1,3-diacetic acid, 1a, was identified as a potential lead. A series of 3-substituted 2-oxopiperazine-1-acetic acids bearing the Arg-Gly equivalent at the 4-position were prepared and evaluated for their ability to prevent platelet aggregation and for their binding affinity for the GP IIb-IIIa receptor purified from human HEL cells. (S)-4-[(4-Amidinobenzoyl)glycyl]-3-[(methoxycarbonyl)methyl]- 2-oxopiperazine-1-acetic acid, 9 (TAK-029), inhibited in vitro human platelet aggregation with an IC50 value of 0.03 microM and GP IIb-IIIa-fibrinogen binding with an IC50 value of 0.49 nM. The [4-(2-aminoethyl)benzoyl]glycyl derivative 26 showed activity comparable to that of 9 (IC50 = 0.093 microM, guinea pig platelet aggregation assay). Compound 9 dose-dependently inhibited ex vivo platelet aggregation in guinea pigs (0.03 and 0.1 mg/kg, i.v.), and long-lasting inhibition of platelet aggregation was observed upon oral administration of 9 (3 mg/kg) to guinea pigs. On the other hand, the activity of 26 disappeared within 1 h after a dose of 1 mg/kg (i.v.). Compound 9 may therefore be useful in the clinical treatment of arterial thrombotic diseases.


Asunto(s)
Oligopéptidos , Piperazinas/síntesis química , Inhibidores de Agregación Plaquetaria/síntesis química , Agregación Plaquetaria/efectos de los fármacos , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Animales , Diseño de Fármacos , Fibrinógeno/metabolismo , Guanidinas/farmacología , Cobayas , Humanos , Técnicas In Vitro , Cinética , Estructura Molecular , Piperazinas/química , Piperazinas/farmacología , Inhibidores de Agregación Plaquetaria/química , Inhibidores de Agregación Plaquetaria/farmacología , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Pirazinas/farmacología , Relación Estructura-Actividad
15.
J Histochem Cytochem ; 39(2): 239-42, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1987268

RESUMEN

The classification of amyloidosis depends on the chemical nature of the specific amyloid protein involved. Because AL amyloid protein consists mainly of variable regions of light chain (LC), immunohistochemical staining with conventional anti-LC antisera cannot identify its protein. We were able to classify three cases of AL amyloidosis, including one case of AL-kappa LC and two cases of AL-lambda LC, using post-embedding protein A-gold immunoelectron microscopy on autopsy-derived tissues. We describe here our procedure in which a protein A-gold staining apparatus was used. The main advantage of this method is that many sections can be stained and washed simultaneously under the same conditions. These results suggest that the post-embedding protein A-gold technique using conventional kappa or lambda LC may be useful in diagnosing AL amyloidosis.


Asunto(s)
Amiloide/metabolismo , Amiloidosis/clasificación , Humanos , Inmunohistoquímica , Microscopía Electrónica , Proteína Estafilocócica A
16.
Immunol Lett ; 72(2): 137-43, 2000 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10841950

RESUMEN

Silicosis is clinically characterized not only by respiratory disorders but by immunological abnormalities such as the appearance of autoantibodies and complications of autoimmune diseases. Dysregulation of apoptosis, particularly in the Fas/Fas ligand (FasL) pathway, has been considered to play a role in the pathogenesis of autoimmune diseases. It has been found that serum soluble Fas (sFas) levels are elevated in silicosis patients (SIL) and the sFas message is dominantly expressed in peripheral blood mononuclear cells (PBMC) derived from these individuals. In the present study, one tried to detect alternatively spliced variant messages including typical sFas message and found four that were highly and frequently expressed, and which possess a signal peptide domain, but not transmembrane and signal transducing domains, in PBMC derived from SIL. Functional mutations were not detected in Fas and FasL genes in silicosis PBMC. Still, alternative spliced variants of the Fas gene including typical sFas message appear to play an important role in the immunological dysregulation in SIL.


Asunto(s)
Empalme Alternativo/genética , Variación Genética/genética , Leucocitos Mononucleares/metabolismo , Glicoproteínas de Membrana/genética , ARN/sangre , Silicosis/genética , Silicosis/inmunología , Receptor fas/genética , Anciano , Secuencia de Aminoácidos , Clonación Molecular , Análisis Mutacional de ADN , Proteína Ligando Fas , Femenino , Humanos , Ligandos , Masculino , Datos de Secuencia Molecular
17.
Br J Pharmacol ; 114(5): 925-30, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7780646

RESUMEN

1. To search for a possible role for endothelin-1 (ET-1) in deoxycorticosterone acetate (DOCA)-salt-induced hypertension, we examined changes in concentration of ET-1 in vascular and renal tissue in DOCA-salt hypertensive rats and evaluated the antihypertensive effect of the ETA receptor antagonist, FR139317. 2. There was an increase in aortic immunoreactive-ET (IR-ET) concentrations in association with hypertension-induced treatment. There were no significant changes in ET-1 levels in the kidney with DOCA-salt treatment. 3. In DOCA-salt hypertensive rats, a significant correlation (r = 0.83, P < 0.01) was found between aortic IR-ET concentrations and systolic blood pressure. 4. High-performance liquid chromatography analysis of the aortic extract from DOCA-salt rats revealed one major component corresponding to the elution position of synthetic ET-1. 5. The intravenous bolus injection of FR139317 (10 mg kg-1) produced a slight decrease in blood pressure in the control rats and in the DOCA-salt hypertensive rat, FR139317 had a more pronounced hypotensive effect. 6. We propose that ET-1 production in vascular tissues is increased in DOCA-salt hypertensive rats. In addition, our study indicates the pathophysiological importance of increased endogenous ET-1 in the maintenance of DOCA-salt-induced hypertension, through interaction of the peptide with ETA receptors.


Asunto(s)
Desoxicorticosterona , Endotelinas/fisiología , Hipertensión/fisiopatología , Receptores de Endotelina/fisiología , Animales , Aorta Torácica/metabolismo , Azepinas/farmacología , Presión Sanguínea/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Antagonistas de los Receptores de Endotelina , Endotelinas/metabolismo , Hipertensión/inducido químicamente , Indoles/farmacología , Riñón/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Vasoconstricción/efectos de los fármacos
18.
Hum Pathol ; 24(9): 970-6, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8253463

RESUMEN

We have studied three cases of localized amyloidosis in the lower respiratory tract. Amyloid was nodularly or diffusely deposited in the lamina propria of the tracheobronchial mucosa. Its nature was confirmed by Congo red staining with green birefringence on polarized microscopy. "Tracheobronchopathia osteoplastica" also was demonstrated. Plasma cells and lymphocytes were scant in the amyloid mass. Few fibroblasts and even fewer macrophages were seen. The number of plasma cells was not increased in the bone marrow in any of our cases. Amyloid fibrils were demonstrated by electron microscopic examination. The amyloid P component was detected by immunohistochemical methods. The precursor protein of amyloidosis was shown to be amyloid L protein by the postembedding protein-A gold technique with anti-light chain antisera. The role of the plasma cells in amyloid formation, however, could not be ascertained. Based on these observations, amyloid fibril formation in tracheobronchial amyloidosis appears to be related to light chains secreted by local plasma cells, combined with amyloid P, calcium, and other factors.


Asunto(s)
Amiloidosis/metabolismo , Amiloidosis/patología , Enfermedades Bronquiales/metabolismo , Enfermedades Bronquiales/patología , Enfermedades de la Tráquea/metabolismo , Enfermedades de la Tráquea/patología , Adulto , Anciano , Amiloide/clasificación , Amiloide/metabolismo , Humanos , Inmunohistoquímica , Masculino , Microscopía Electrónica , Microscopía Inmunoelectrónica , Persona de Mediana Edad
19.
Brain Res Mol Brain Res ; 89(1-2): 158-63, 2001 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-11311987

RESUMEN

Following rat hypoglossal nerve injury, expression of mRNAs for a disintegrin and metalloprotease with thrombospondin type1 motifs (ADAMTS-1) and IL-1 receptor type 1 (IL-1RT1) are induced in the injured motor neurons. Although N1E-115 (N1E) cells, which were treated with IL-1 alpha, showed no alteration of ADAMTS-1 mRNA expression, a substantial increase of ADAMTS-1 mRNA expression was observed in the N1E cells expressing IL-1RT1. These findings suggest that nerve injury promotes IL-1RT1 expression in the injured neurons and thereby ADAMTS-1 transcription was induced in response to IL-1 released from glial cells.


Asunto(s)
Desintegrinas/genética , Metaloendopeptidasas/genética , Neuronas Motoras/fisiología , Receptores de Interleucina-1/genética , Proteínas ADAM , Proteína ADAMTS1 , Animales , Axotomía , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Nervio Hipogloso/citología , Nervio Hipogloso/fisiología , Interleucina-1/farmacología , Masculino , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/fisiología , ARN Mensajero/análisis , Ratas , Ratas Wistar
20.
J Biochem ; 122(1): 201-4, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9276689

RESUMEN

Crystals of recombinant Pseudomonas putida catechol 2,3-dioxygenase, metapyrocate-chase, composed of four identical subunits, each with a molecular mass of 35 kDa and one nonheme ferrous iron, have been grown by the vapor diffusion method using sodium citrate as the precipitant. Repeated macroseeding and the addition of ethanol to protein solutions were together effective for obtaining crystals suitable for further crystallographic characterization. The crystals belong to the tetragonal space group P4(2)2(1)2 with unit-cell dimensions of a = b = 266 A, c = 60 A. They diffracted beyond 2.5 A resolution with synchrotron radiation. Assuming that one tetramer (alpha-Fe2+)4 is contained in an asymmetric unit, the crystal volume per unit molecular mass, Vm, is calculated to be 3.8 A3/Da, which corresponds to the solvent content of 67.6%.


Asunto(s)
Dioxigenasas , Oxigenasas/química , Pseudomonas putida/enzimología , Catecol 2,3-Dioxigenasa , Cristalización , Cristalografía por Rayos X , Oxigenasas/genética , Oxigenasas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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