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1.
Clin Exp Allergy ; 46(9): 1152-61, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26765219

RESUMEN

BACKGROUND: Several gene variants identified in bronchial asthmatic patients are associated with a decrease in pulmonary function. The effects of this intervention on pulmonary function have not been fully researched. OBJECTIVE: We determined the effects of high-dose inhaled corticosteroids (ICSs) on decreased pulmonary function in asthmatic Japanese patients with variants of IL13 and STAT4 during long-term treatments with low to mild doses of ICS. METHODS: In this study, 411 patients with bronchial asthma who were receiving ICSs and living in Japan were recruited, were genotyped, and underwent pulmonary function tests and fibreoptic examinations. The effects of 2 years of high-dose ICSs administered to asthmatic patients who were homozygous for IL13 AA of rs20541 or STAT4 TT of rs925847 and who progressed to airway remodelling were investigated. RESULTS: High-dose ICS treatment increased the pulmonary function of patients homozygous for IL13 AA of rs20541 but not of patients homozygous for STAT4 TT of rs925847. The increased concentrations of the mediators IL23, IL11, GMCSF, hyaluronic acid, IL24, and CCL8 in bronchial lavage fluid (BLF) were diminished after high-dose ICS treatment in patients homozygous for IL13 AA of rs20541. CONCLUSION AND CLINICAL RELEVANCE: IL13 AA of rs20541 and STAT4 TT of rs925847 are potential genomic biomarkers for predicting lower pulmonary function. The administration of high-dose ICSs to asthmatic patients with genetic variants of IL13 AA may inhibit the advancement of airway remodelling. The genetic variants of STAT4 TT did not respond to high-dose ICSs. Therefore, using medications other than ICSs must be considered even during the initial treatment of bronchial asthma. These genetic variants may aid in the realization of personalized and phenotype-specific therapies for bronchial asthma.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/genética , Asma/genética , Asma/patología , Predisposición Genética a la Enfermedad , Variación Genética , Interleucina-13/genética , Factor de Transcripción STAT4/genética , Administración por Inhalación , Corticoesteroides/administración & dosificación , Remodelación de las Vías Aéreas (Respiratorias)/efectos de los fármacos , Alelos , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Asma/metabolismo , Biomarcadores , Líquido del Lavado Bronquioalveolar , Citocinas/metabolismo , Eosinófilos , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Inmunoglobulina E/inmunología , Interleucina-13/metabolismo , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Pruebas de Función Respiratoria , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Factor de Transcripción STAT4/metabolismo
2.
Neuropathol Appl Neurobiol ; 42(6): 561-72, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26819002

RESUMEN

AIMS: Axonal aggregates of phosphorylated (p-) transactive response DNA-binding protein 43 kDa (TDP-43) in sporadic amyotrophic lateral sclerosis (sALS) were examined in relation to propagation of the protein in the nervous system. METHODS: Brains and spinal cords of Japanese patients with sALS and control subjects were examined immunohistochemically using formalin-fixed paraffin-embedded specimens with special reference to the topographical distribution, microscopic features, presynaptic aggregates, and correlation between the aggregates in axons and the clinical course. RESULTS: (i) Aggregates of p-TDP-43 were frequently present in axons of the hypoglossal and facial nerve fibres and the spinal anterior horn cells. (ii) Aggregates of p-TDP-43 in the axons showed two characteristic microscopic features - dash-like granuloreticular aggregates (GRAs) and massive aggregates (MAs). (iii) MAs were surrounded by p-neurofilaments, but p-neurofilament immunnoreactivity decreased at the inside of axons with GRAs. (iv) Patients showing MAs and GRAs had a relatively shorter clinical course than patients without the aggregates. (v) Some neurones in the red nucleus in patients were surrounded by synapses containing p- and p-independent (i)-TDP-43, and almost all neurones had lost their nuclear TDP-43 immunoreactivity; 17% of those neurones in the red nucleus also had TDP-43-immunopositive neuronal cytoplasmic inclusions, but no postsynaptic p-TDP-43 deposition was evident. CONCLUSIONS: There are two types of axonal p-TDP-43 aggregates, MAs and GRAs, located predominantly in the facial and hypoglossal nuclei and anterior horn cells. These aggregates may influence the function of neurones, and presynaptic aggregates of the protein induce loss of p-i-TDP-43 in the nuclei of postsynaptic neurones.


Asunto(s)
Esclerosis Amiotrófica Lateral/patología , Axones/patología , Proteínas de Unión al ADN/metabolismo , Cuerpos de Inclusión/patología , Anciano , Anciano de 80 o más Años , Esclerosis Amiotrófica Lateral/metabolismo , Pueblo Asiatico , Axones/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Femenino , Humanos , Cuerpos de Inclusión/metabolismo , Masculino , Persona de Mediana Edad , Médula Espinal/metabolismo , Médula Espinal/patología
4.
Cryobiology ; 65(2): 113-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22609515

RESUMEN

The supercooling and vitrification of aqueous glycerol solutions was studied at high pressures. Homogeneous ice nucleation temperatures (T(H)) were obtained for aqueous glycerol solutions of R=50, 30, 20, 12, and 10 (R: moles of water/moles of glycerol) up to 300MPa. The R=20 glycerol solution formed a glass above 200MPa at a cooling rate of 200°C/min, indicating that pressure enhances glass-formation of aqueous glycerol solutions. The (dT(g)/dP) values were obtained for vitrified aqueous glycerol solutions of R=3, 5, 10, and 20. These data can be used for the development of cryo-preservation liquids for living cells at high pressures.


Asunto(s)
Crioprotectores/química , Glicerol/química , Vitrificación , Frío , Presión , Temperatura de Transición , Agua/química
5.
J Chem Phys ; 132(19): 194503, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20499975

RESUMEN

Supercooling behavior of aqueous dimethylsulfoxide (DMSO) solution was investigated as a function of DMSO concentration and at high pressures. A linear relationship was observed for T(H) (homogeneous ice nucleation temperature) and T(m) (melting temperature) for the supercooling of aqueous DMSO solution at normal pressure. Analysis of the DTA (differential thermal analysis) traces for homogeneous ice crystallization in the bottom region of the T(H) curve for a DMSO solution of R=20 (R: moles of water/moles of DMSO) at high pressures supported the contention that the second critical point (SCP) of liquid water should exist at P(c2)= approximately 200 MPa and at T(c2)<-100 degrees C (P(c2): pressure of SCP, T(c2): temperature of SCP). The presence of two T(H) peaks for DMSO solutions (R=15, 12, and 10) suggests that phase separation occurs in aqueous DMSO solution (R

Asunto(s)
Dimetilsulfóxido/química , Congelación , Estructura Molecular , Transición de Fase , Presión , Soluciones , Agua/química
6.
Clin Genet ; 75(2): 157-62, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18759866

RESUMEN

Eighteen unrelated pyruvate kinase (PK)-deficient Indian patients were identified in the past 4 years with varied clinical phenotypes ranging from a mild chronic haemolytic anaemia to a severe transfusion-dependent disorder. We identified 17 different mutations in the PKLR gene among the 36 mutated alleles. Ten novel mutations were identified: 427G>A, 499C>A, 1072G>A, 1180G>T, 1216G>A, 1220A>G, 644delG, IVS5 (+20) C>A, IVS9 (+44) C>T, and IVS9 (+93) A>C. A severe syndrome was commonly associated with some mutations, 992A>G, 1436G>A, 1220A>G, 644delG and IVS9 (+93) A>C, in the PKLR gene. Molecular graphics analysis of human red blood cell PK (RPK), based on the crystal structure of human PK, shows that mutations located near the substrate or fructose 1,6-diphosphate binding site may change the conformation of the active site, resulting in very low PK activity and severe clinical symptoms. The mutations target distinct regions of RPK structure, including domain interfaces and catalytic and allosteric sites. In particular, the 1216G>A and 1219G>A mutations significantly affect the interdomain interaction because they are located near the catalytic site in the A/B interface domains. The most frequent mutations in the Indian population appear to be 1436G>A (19.44%), followed by 1456C>T (16.66%) and 992A>G (16.66%). This is the first study to correlate the clinical profile with the molecular defects causing PK deficiency from India where 10 novel mutations that produce non-spherocytic haemolytic anaemia were identified.


Asunto(s)
Anemia Hemolítica/diagnóstico , Anemia Hemolítica/genética , Mutación , Fenotipo , Piruvato Quinasa/deficiencia , Piruvato Quinasa/genética , Adulto , Anemia Hemolítica/patología , Eritrocitos/enzimología , Eritrocitos/metabolismo , Femenino , Humanos , India , Lactante , Masculino , Modelos Moleculares , Conformación Proteica , Piruvato Quinasa/metabolismo , Relación Estructura-Actividad , Adulto Joven
7.
Science ; 193(4258): 1121-2, 1976 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-17792749

RESUMEN

With glass capillary pressure vessels it has been possible to study the effect of pressure on the temperature of maximum density (TMD) and on the "sharpness" of the density maximum in liquid H(2)O and D(2)O in the important but little-studied supercooled regime. A pressure of 1200 bars produces a 33 degrees C depression of the TMD in these liquids and a considerable reduction in sharpness. Comparison with the rather flat density maximum for liquid SiO(2) supports the notion that the presence or absence of density anomalies in "tetrahèdral" liquids depends on the average bridge-bond angle, which is evidently unusually large in water at normal pressure.

8.
Science ; 189(4206): 880-1, 1975 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-17812529

RESUMEN

The temperature at which "clean" supercooled water freezes has been determined as a function of pressure up to 3 kilobars, using a differential thermal analysis technique on subdivided water samples. The supercooling limit of such samples, -38 degrees C at normal pressure, is lowered by initial increase of pressure, reaching a minimum value of -92 degrees C at 2.00 kilobars.

9.
Spinal Cord ; 47(6): 447-52, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19030009

RESUMEN

STUDY DESIGN: Retrospective data analysis. OBJECTIVE: To clarify the clinical features and surgical management of spinal cord hemangioblastomas in patients with von Hippel-Lindau disease (VHL). SETTING: Clinical VHL Research Group in Japan, Japan. METHODS: Forty-eight out of 66 patients with associated spinal cord hemangioblastoma among 142 VHL patients were retrospectively examined with respect to clinical features, accompanying lesions and outcome of surgical treatment. RESULTS: Among these 48 patients, 46 of them (95.8%) also had a central nervous system (CNS) hemangioblastoma at another site: 42 (87.5%) with cerebellar hemangioblastoma and 11 (22.9%) with brain stem hemangioblastoma. Twenty-three patients (47.9%) had more than one spinal cord hemangioblastoma. The 48 patients with spinal cord hemangioblastomas collectively had a total of 74 tumors. The tumor was accompanied with a syrinx in 64 and without it in 10 patients. Forty of the 48 patients underwent surgical treatment for their spinal cord hemangioblastomas, and 7 of these 40 underwent surgical treatment twice. When functional changes in the patients after these 47 operations were examined by postoperative evaluation by McCormick's classification, 39 of these operations (83.0%) resulted in improvement/no change and 8 (17.0%) in aggravation of symptoms. CONCLUSION: Von Hippel-Lindau disease patients bearing spinal cord hemangioblastomas mostly had a CNS hemangioblastoma at another site. These tumors can be removed in the majority of VHL patients without aggravation. In these patients, when the timing of treatment for spinal cord hemangioblastoma is determined, the probability of occurrence and treatment of other lesions should be considered.


Asunto(s)
Hemangioblastoma/etiología , Hemangioblastoma/cirugía , Neoplasias de la Médula Espinal/etiología , Neoplasias de la Médula Espinal/cirugía , Enfermedad de von Hippel-Lindau/complicaciones , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
10.
Clin Exp Immunol ; 151(3): 519-27, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18190605

RESUMEN

Chronic active Epstein-Barr virus (EBV) infection (CAEBV) is characterized by chronic recurrent infectious mononucleosis-like symptoms. Approximately one-fourth of CAEBV patients develop vascular lesions with infiltration of EBV-positive lymphoid cells. Furthermore, EBV-positive natural killer (NK)/T cell lymphomas often exhibit angiocentric or angiodestructive lesions. These suggest an affinity of EBV-positive NK/T cells to vascular components. In this study, we evaluated the expression of adhesion molecules and cytokines in EBV-positive NK lymphoma cell lines, SNK1 and SNK6, and examined the role of cytokines in the interaction between NK cell lines and endothelial cells. SNKs expressed intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) at much higher levels than those in EBV-negative T cell lines. SNKs produced the larger amount of tumour necrosis factor (TNF)-alpha, which caused increased expression of ICAM-1 and VCAM-1 in cultured human endothelial cells, than that from EBV-negative T cell lines. Furthermore, SNKs exhibited increased adhesion to cultured endothelial cells stimulated with TNF-alpha or interleukin (IL)-1beta, and the pretreatment of cytokine-stimulated endothelial cells with anti-VCAM-1-antibodies reduced cell adhesion. These indicate that the up-regulated expression of VCAM-1 on cytokine-stimulated endothelial cells would be important for the adhesion of EBV-positive NK cells and might initiate the vascular lesions.


Asunto(s)
Citocinas/inmunología , Endotelio Vascular/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Células Asesinas Naturales/virología , Adhesión Celular/inmunología , Citocinas/metabolismo , Células Endoteliales/inmunología , Humanos , Integrina alfa4beta1/metabolismo , Molécula 1 de Adhesión Intercelular/inmunología , Molécula 1 de Adhesión Intercelular/metabolismo , Células Asesinas Naturales/inmunología , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Linfoma de Células T/inmunología , Linfoma de Células T/virología , Células Tumorales Cultivadas , Molécula 1 de Adhesión Celular Vascular/inmunología , Molécula 1 de Adhesión Celular Vascular/metabolismo
11.
Int J Oral Maxillofac Surg ; 37(1): 82-5, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17611076

RESUMEN

Catheter placement for continuous intra-arterial chemotherapy in head and neck cancer is generally performed via the superficial temporal artery. If placement via this artery is impossible, other arteries, such as the occipital artery, are chosen. A surgical method has been developed for catheter placement in the occipital artery by approaching from the posterior of the mastoid process. Catheter placement was performed by this method in 15 patients with oral squamous cell carcinoma. Target arteries were the lingual artery in seven cases, facial artery in three cases, maxillary artery in three cases, superior thyroid artery in one case, and the occipital artery itself in one case. The occipital artery was exposed without fail and catheter placement was completed in all patients. The wound healed without complication after treatment. This approach via the occipital artery is a useful technique to achieve continuous intra-arterial chemotherapy in head and neck cancer, especially for cases in which catheter placement is impossible via the superficial temporal artery.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Arteria Carótida Externa/cirugía , Catéteres de Permanencia , Infusiones Intraarteriales/métodos , Neoplasias de la Boca/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Arteria Carótida Externa/diagnóstico por imagen , Femenino , Humanos , Masculino , Apófisis Mastoides , Persona de Mediana Edad , Radiografía
12.
Genet Mol Res ; 6(2): 470-5, 2007 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-17952871

RESUMEN

Pyruvate kinase (PK) deficiency is a rare red cell glycolytic enzymopathy. The purpose of the present investigation was to offer prenatal diagnosis for PK deficiency to a couple who had a previous child with severe enzyme deficiency and congenital non-spherocytic hemolytic anemia. PK deficiency was identified in the family by assaying the enzyme activity in red cells. Chorionic villus sampling was performed in an 11-week gestation and the mutation was located in exon 10 of the PKLR gene characterized by polymerase chain reaction and using restriction endonuclease digestion with the MspI enzyme, which was confirmed by DNA sequencing on the ABI 310 DNA sequencer. Both the parents were heterozygous for the 1436G-->A [479 Arg-->His] mutation in exon 10 and the proband was homozygous for this mutation. The fetus was also heterozygous for this mutation and the pregnancy was continued. Prenatal diagnosis allowed the parents with a severely affected child with PK deficiency to have the reproductive choice of having the fetus tested in a subsequent pregnancy.


Asunto(s)
Anemia Hemolítica Congénita no Esferocítica/diagnóstico , Mutación , Diagnóstico Prenatal/métodos , Piruvato Quinasa/deficiencia , Piruvato Quinasa/genética , Anemia Hemolítica/genética , Anemia Hemolítica Congénita no Esferocítica/genética , Análisis Mutacional de ADN , Enzimas de Restricción del ADN/metabolismo , Exones , Femenino , Homocigoto , Humanos , India , Masculino , Embarazo , Primer Trimestre del Embarazo
13.
Cancer Res ; 60(11): 2820-4, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10850421

RESUMEN

The von Hippel-Lindau (VHL) tumor suppressor protein down-regulates transcription by transcriptional elongation enhanced by antagonizing elongin B and C. Transcriptional regulation is an important control mechanism for embryogenesis and tumorigenesis. The VHL gene and protein are expressed in neuronal cells of the fetal and adult brain. However, the role of the VHL gene in the central nervous system (CNS) has not been elucidated. The VHL gene might modify the expression of various genes during embryogenesis and tumorigenesis in CNS. We investigated the role of the VHL gene in CNS development using rodent CNS progenitor cells. Here we show that expression of the VHL protein is correlated with neuronal differentiation but not with glial differentiation in CNS progenitor cells, and we also show that VHL gene transduction induces neuronal differentiation. In addition, a VHL mRNA antisense oligonucleotide inhibits differentiation of CNS progenitor cells and up-regulates their cell cycle. In conclusion, the VHL gene plays an essential role in neuronal differentiation as well as transcription.


Asunto(s)
Diferenciación Celular , Ligasas , Proteínas del Tejido Nervioso , Neuronas/citología , Neuronas/fisiología , Proteínas/fisiología , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Animales , Western Blotting , Regulación hacia Abajo , Embrión de Mamíferos/fisiología , Factor de Crecimiento Epidérmico/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Regulación de la Expresión Génica , Genes Supresores de Tumor/fisiología , Proteína Ácida Fibrilar de la Glía/metabolismo , Inmunohistoquímica , Proteínas de Filamentos Intermediarios/metabolismo , Microscopía Confocal , Proteínas Asociadas a Microtúbulos/metabolismo , Nestina , Oligonucleótidos Antisentido/metabolismo , Proteínas/genética , Ratas , Ratas Sprague-Dawley , Células Madre/metabolismo , Factores de Tiempo , Transcripción Genética , Transducción Genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau
14.
Cancer Res ; 57(6): 1035-8, 1997 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-9067265

RESUMEN

Molecular genetic analysis of von Hippel-Lindau tumor suppressor gene (VHL gene) was performed on 38 tissues of human glial tumors (ependymoma, 1; astrocytoma, 6; oligodendroglioma, 1; oligoastrocytoma, 2; anaplastic oligoastrocytoma, 3; anaplastic astrocytoma, 14; glioblastoma multiforme, 11). Somatic DNAs extracted from frozen tumor specimens were examined by single-strand conformational polymorphism analysis and direct sequencing. In addition, loss of heterozygosity (LOH) on chromosome 3p in 15 glial tumor cases, lymphocyte DNAs of which were available, was examined by use of 10 microsatellite probes and two polymorphism markers for the VHL gene. Two cases of low-grade gliomas showed somatic sense mutations in exon 3 of the VHL gene, and 6 of 15 cases (40.0%) showed LOH of chromosome 3p. The VHL gene-mutated cases also showed LOH. The retention of heterozygosity and high pathological grade of glial tumors were correlated significantly. In addition, Kaplan-Meier survival analysis for patients with glial tumors showed that patients with LOH had a significantly longer survival time than those without LOH. These results suggest that somatic mutations on 3p, including the VHL gene, may be involved in tumorigenesis of some low-grade glial tumors.


Asunto(s)
Neoplasias Encefálicas/genética , Cromosomas Humanos Par 3/genética , ADN de Neoplasias/genética , Eliminación de Gen , Genes Supresores de Tumor , Glioma/genética , Ligasas , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Adulto , Anciano , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Análisis Mutacional de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Glioma/mortalidad , Glioma/patología , Heterocigoto , Humanos , Tablas de Vida , Masculino , Persona de Mediana Edad , Polimorfismo Conformacional Retorcido-Simple , Proteínas/genética , Análisis de Supervivencia , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau
15.
Cancer Res ; 54(18): 4845-7, 1994 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8069849

RESUMEN

Hemangioblastoma is one of the benign tumors in the central nervous system. It is often associated with the von Hippel-Lindau (VHL) disease, a well known hereditary tumor syndrome. It is believed that inactivation of both alleles of VHL tumor suppressor gene is essential in the tumorigenic processes in hemangioblastomas associated with VHL disease. The molecular basis for the development of sporadic hemangioblastomas is not known. Here, we analyzed 13 cases of primary sporadic hemangioblastomas for somatic mutations of VHL gene with single strand conformational polymorphism analyses of the tumor DNAs. We detected abnormal single strand conformational polymorphism pattern in 7 tumors (54%). Of these 7 possibly mutated tumors, we successfully characterized 3 tumors by direct sequencing. We were unable to sequence 4 tumors because of the poor quality of DNA obtained from paraffin blocks. Somatic mutations in the 3 tumors were 2 missense mutations and 1 microdeletion. These mutations were observed in 1 tumor in exon 1 and 2 tumors in exon 2. Our results suggest that mutations of VHL tumor suppressor gene are involved in the development of at least 20% of sporadic central nervous system hemangioblastomas.


Asunto(s)
Neoplasias Cerebelosas/genética , Genes Supresores de Tumor/genética , Hemangioblastoma/genética , Mutación/genética , Enfermedad de von Hippel-Lindau/genética , Secuencia de Bases , Exones/genética , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo Genético
16.
AJNR Am J Neuroradiol ; 37(4): 730-5, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26564439

RESUMEN

BACKGROUND AND PURPOSE: Axial-loaded MR imaging, which simulates the spinal canal in a standing position, demonstrates reductions of the dural sac cross-sectional area in patients with lumbar spinal canal stenosis. However, there has been no useful conventional MR imaging finding for predicting a reduction in the dural sac cross-sectional area on axial-loaded MR imaging. Previous studies have shown that increased facet fluid is associated with the spinal instability detected during positional changes. The purpose of this study was to analyze the correlations between facet fluid and dynamic changes in the dural sac cross-sectional area on axial-loaded MR imaging. MATERIALS AND METHODS: In 93 patients with lumbar spinal canal stenosis, the dural sac cross-sectional area was measured by using axial images of conventional and axial-loaded MR imaging. Changes in the dural sac cross-sectional area induced by axial loading were calculated. The correlation between the facet fluid width measured on conventional MR imaging and the change in dural sac cross-sectional area was analyzed. The change in the dural sac cross-sectional area was compared between the intervertebral levels with and without the facet fluid width that was over the cutoff value determined in this study. RESULTS: The dural sac cross-sectional area was significantly smaller on axial-loaded MR imaging than on conventional MR imaging. The facet fluid width significantly correlated with the change in the dural sac cross-sectional area (r = 0.73, P < .001). The change in the dural sac cross-sectional area at the intervertebral level with the facet fluid width over the cutoff value was significantly greater than that at the other level. CONCLUSIONS: The increased facet fluid on conventional MR imaging is highly predictive of the dynamic reduction of dural sac cross-sectional area detected on axial-loaded MR imaging in the clinical assessment of lumbar spinal canal stenosis.


Asunto(s)
Duramadre/patología , Vértebras Lumbares/patología , Estenosis Espinal/patología , Articulación Cigapofisaria/patología , Anciano , Anatomía Transversal , Líquidos Corporales , Duramadre/diagnóstico por imagen , Femenino , Humanos , Disco Intervertebral/diagnóstico por imagen , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/epidemiología , Degeneración del Disco Intervertebral/etiología , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Estenosis Espinal/diagnóstico por imagen , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/epidemiología , Espondilolistesis/etiología , Articulación Cigapofisaria/diagnóstico por imagen
17.
Biochim Biophys Acta ; 914(1): 89-95, 1987 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-3300780

RESUMEN

Spectroscopic and structural properties of three homologous dimeric inhibitors of microbial origin, Streptomyces subtilisin inhibitor, alkaline proteinase inhibitor and plasminostreptin, were discussed by comparing the hydropathy maps, the secondary structure contents obtained from the CD analysis, and the Chou and Fasman prediction. The major process of thermal denaturation of these proteins was the two-step transition. The denaturation temperature dropped in the order Streptomyces subtilisin inhibitor greater than alkaline proteinase inhibitor greater than plasminostreptin. Differences in the denaturation temperature were interpreted in terms of differences in the hydropathy scale of side-chains of the alpha 1-helix of these proteins. The lower CD change upon the complex formation of plasminostreptin with subtilisin BPN' than those with of Streptomyces subtilisin inhibitor and alkaline proteinase inhibitor was explained in terms of the large increase in hydrophilicity of the contact region of plasminostreptin with the enzyme.


Asunto(s)
Proteínas Bacterianas , Inhibidores de Proteasas , Subtilisinas/antagonistas & inhibidores , Secuencia de Aminoácidos , Dicroismo Circular , Calor , Conformación Proteica , Desnaturalización Proteica , Streptomyces/enzimología , Difracción de Rayos X
18.
J Mol Biol ; 236(3): 710-24, 1994 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-8114089

RESUMEN

Molecular recognition of Escherichia coli tRNA(Ile) by the cognate isoleucyl-tRNA synthetase (IleRS) was studied by analyses of chemical footprinting with N-nitroso-N-ethylurea and aminoacylation kinetics of variant tRNA(Ile) transcripts prepared with bacteriophage T7 RNA polymerase. IleRS binds to the acceptor, dihydrouridine (D), and anticodon stems as well as to the anticodon loop. The "complete set" of determinants for the tRNA(Ile) identity consists of most of the nucleotides in the anticodon loop (G34, A35, U36, t6A37 and A38), the discriminator nucleotide (A73), and the base-pairs in the middle of the anticodon, D and acceptor stems (C29.G41, U12.A23 and C4.G69, respectively). As for the tertiary base-pairs, two are indispensable for the isoleucylation activity, whereas the others are dispensable. Correspondingly, some of the phosphate groups of these dispensable tertiary base-pair residues were shown to be exposed to N-nitroso-N-ethylurea when tRNA(Ile) was bound with IleRS. Furthermore, deletion of the T psi C-arm only slightly impaired the tRNA(Ile) activity. Thus, it is proposed that the recognition by IleRS of all the widely distributed identity determinants is coupled with a global conformational change that involves the loosening of a particular set of tertiary base-pairs of tRNA(Ile).


Asunto(s)
Escherichia coli/metabolismo , Isoleucina-ARNt Ligasa/metabolismo , Conformación de Ácido Nucleico , ARN de Transferencia de Isoleucina/química , Anticodón/química , Composición de Base , Secuencia de Bases , Sitios de Unión , Gráficos por Computador , Escherichia coli/genética , Genes Bacterianos , Genes Sintéticos , Modelos Moleculares , Datos de Secuencia Molecular , Desnaturalización de Ácido Nucleico , ARN de Transferencia de Isoleucina/metabolismo
19.
Leukemia ; 11 Suppl 3: 525-6, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9209445

RESUMEN

Malignant lymphoma frequently develops in the pleural cavity of the patients with long-standing pyothorax. Thus, the term pyothorax-associated lymphoma (PAL) has been proposed for this type of tumor. Most of PALs are diffuse lymphoma of B cell type and contain Epstein-Barr virus (EBV) DNA. We have established two lymphoma cell lines from the biopsy specimens of PAL cases, OPL-1 and OPL-2. Both cell lines contain EBV DNA, but only OPL-1 expresses Epstein-Barr virus nuclear antigen 2 (EBNA2) that works as a target molecule for cell-mediated immune response. In this study, we examined the expression of immunosuppressive factors in OPLs. Only OPL-1, not OPL-2, expressed interleukin-10 (IL-10) mRNA and secreted IL-10 into culture supernatant. Both OPL-1 and OPL-2 expressed transforming growth factor (TGF) beta 1 mRNA, however, neither expressed latent TGF beta binding protein (LTBP) mRNA at detectable level by Northern blot analysis. Because TGF beta expresses its functions in cooperation with LTBP, the biological functions of TGF beta 1 could be negligible. Neither cell lines expressed EBV BCRF1 mRNA at detectable level, a viral gene product which is partly homologous to human IL-10 and shares biological activities of IL-10. Since OPL-1 shows weaker proliferative activity than OPL-2 and expresses viral antigens, the production of an immunosuppressive cytokine, IL-10, might contribute to the development of overt lymphoma. The present study suggested that immunosuppressive cytokine plays a role in lymphomagenesis of immunocompetent patients.


Asunto(s)
Empiema Pleural/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Interleucina-10/biosíntesis , Linfoma de Células B/patología , Neoplasias Pleurales/patología , ADN Viral/análisis , Empiema Pleural/complicaciones , Antígenos Nucleares del Virus de Epstein-Barr/biosíntesis , Humanos , Tolerancia Inmunológica , Interleucina-10/fisiología , Linfoma de Células B/etiología , Linfoma de Células B/inmunología , Neoplasias Pleurales/etiología , Neoplasias Pleurales/inmunología , Antígeno Nuclear de Célula en Proliferación/biosíntesis , Transcripción Genética , Factor de Crecimiento Transformador beta/biosíntesis , Células Tumorales Cultivadas
20.
Leukemia ; 3(1): 36-41, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2491896

RESUMEN

We studied chromosomes of BM cells from four neurofibromatosis (NF) patients with leukemia. One patient had a normal diploid karyotype in the chronic phase of juvenile chronic myelogenous leukemia (JCML). When the the leukemia evolved into the accelerated phase, she had cells with 46,XX,-7,+der(7)t(3;7)(q21;p22); the abnormalities resulted in a partial 7p deletion. In another patient with JCML, BM cells in the accelerated phase had 45,XY,-7. The abnormal cells with monosomy 7 disappeared from the BM after chemotherapy but reappeared later in the course. Another patient developed refractory anemia with excess of blasts in transformation (RAEB-T) and had cells with 46,XX,-6,+r(6)(p23?q21?); the abnormalities resulted in partial 6p and 6q deletions. The other patient with ANLL had cells with 45,XX,-7. Our findings and review of data on nine other patients suggest that BM cells of NF patients with JCML in chronic phase have no microscopically detectable chromosome changes and that cells with chromosomal deletion emerge when JCML evolve into the accelerated or blast phase. Thus, deletion of the whole or part of certain chromosomes, such as chromosomes 6, 7, etc., may be an important step towards the evolution of JCML cells or the development of de novo acute leukemias in NF patients.


Asunto(s)
Aberraciones Cromosómicas/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Neurofibromatosis 1/complicaciones , Niño , Preescolar , Aberraciones Cromosómicas/complicaciones , Aberraciones Cromosómicas/patología , Bandeo Cromosómico , Trastornos de los Cromosomas , Femenino , Humanos , Lactante , Cariotipificación , Leucemia Mielógena Crónica BCR-ABL Positiva/complicaciones , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/patología , Masculino , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/patología , Neurofibromatosis 1/genética , Neurofibromatosis 1/patología
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