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3.
Br J Dermatol ; 185(3): e69, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34096040
5.
Science ; 189(4203): 632-4, 1975 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-17838752

RESUMEN

Thermistor chain measurements of internal wave motions below the thermocline in the western North Atlantic have been spectrally decomposed in vertical-horizontal wave number space. The measured two-dimensional spectrum exhibits a systematic deviation from the corresponding Garrett and Munk model for internal wave spectra.

6.
J Med Genet ; 45(3): 134-41, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17993578

RESUMEN

OBJECTIVE: Familial haemophagocytic lymphohistiocytosis (FHL) is a fatal disorder of immune dysregulation with defective cytotoxic lymphocyte function. Disease-causing mutations have been identified in the genes encoding perforin (PRF1), syntaxin-11 (STX11), and Munc13-4 (UNC13D). We screened for UNC13D mutations and studied clinical and functional implications of such mutations in a well defined patient cohort. METHODS: Sequencing of UNC13D was performed in 38 FHL patients from 34 FHL families in which PRF1 and STX11 mutations had been excluded. RESULTS: We identified six different mutations affecting altogether 9/38 individuals (24%) in 6/34 (18%) unrelated PRF1/STX11-negative families. Four novel mutations were revealed; two homozygous nonsense mutations (R83X and W382X), one splice mutation (exon 28), and one missense mutation (R928P). In addition, two known mutations were identified (R214X and a deletion resulting in a frame-shift starting at codon 782). There was considerable variation in the age at diagnosis, ranging from time of birth to 14 years (median 69 days). Three of nine patients (33%) developed central nervous system (CNS) symptoms. Natural killer (NK) cell activity was impaired in all four patients studied. Defective cytotoxic lymphocyte degranulation was evident in the two patients investigated, more pronounced in the patient with onset during infancy than in the patient with adolescent onset. CONCLUSIONS: Biallelic UNC13D mutations were found in 18% of the PRF1/STX11-negative FHL families. Impairment of NK cell degranulation was less pronounced in a patient with adolescent onset. FHL should be considered not only in infants but also in adolescents, and possibly young adults, presenting with fever, splenomegaly, cytopenia, hyperferritinaemia, and/or CNS symptoms.


Asunto(s)
Linfohistiocitosis Hemofagocítica/genética , Proteínas de la Membrana/genética , Mutación , Adolescente , Edad de Inicio , Degranulación de la Célula , Niño , Preescolar , Codón sin Sentido/genética , Femenino , Mutación del Sistema de Lectura , Heterocigoto , Homocigoto , Humanos , Lactante , Recién Nacido , Células Asesinas Naturales/inmunología , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/inmunología , Masculino , Proteínas de la Membrana/inmunología , Mutación Missense , Perforina , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Qa-SNARE/genética , Eliminación de Secuencia
7.
J Med Genet ; 43(4): e14, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16582076

RESUMEN

OBJECTIVE: To determine the frequency and spectrum of mutations in the gene encoding syntaxin 11 (STX11) in familial haemophagocytic lymphohistiocytosis (FHL), a rare autosomal recessive disorder of immune dysregulation characterised by a defect in natural killer cell function. METHODS: Mutational analysis of STX11 by direct sequencing was done in 28 FHL families that did not harbour perforin mutations, previously identified in some FHL patients. A detailed investigation of clinical features of these patients was also undertaken. RESULTS: Two different STX11 mutations were identified, one nonsense mutation and one deletion, affecting six of 34 children in four of 28 unrelated PRF1 negative families. Both mutations have been reported before. Three patients experienced long periods (> or = 1 year) in remission without specific treatment, which is very uncommon in this disease. Despite the milder phenotype, some children with STX11 mutations developed severe psychomotor retardation. Two of the six patients harbouring STX11 gene defects developed myelodysplastic syndrome (MDS) or acute myelogenous leukaemia (AML). CONCLUSIONS: STX11 gene mutations were found in 14% of the PRF1 negative FHL families included in the present cohort. These results suggest that STX11 gene mutations may be associated with secondary malignancies (MDS/AML), and that there is segregation of specific clinical features in FHL patients with an underlying genotype.


Asunto(s)
Leucemia Mieloide/genética , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/genética , Mutación , Síndromes Mielodisplásicos/genética , Proteínas Qa-SNARE/genética , Enfermedad Aguda , Adulto , Anciano de 80 o más Años , Niño , Preescolar , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Lactante , Leucemia Mieloide/complicaciones , Linfohistiocitosis Hemofagocítica/complicaciones , Masculino , Síndromes Mielodisplásicos/complicaciones , Linaje , Fenotipo , Trastornos Psicomotores/complicaciones , Trastornos Psicomotores/genética , Remisión Espontánea
8.
Biochim Biophys Acta ; 918(2): 106-14, 1987 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-3828371

RESUMEN

Carboxylester lipase (cholesterol esterase, EC 3.1.1.13) has been purified to homogeneity from porcine pancreas. The enzyme is isolated in two molecular mass forms, a monomer of 74 kDa and a dimer of 167 kDa. The dimer consists of two catalytically-active subunits which have molecular masses approximately 9 kDa greater than the monomers. The difference in size was not attributable to carbohydrate or lipid content. The catalytic properties of the two forms are comparable on a weight basis, the amino acid compositions are quite similar, and the N-terminal sequences are nearly identical for 24 residues. These similarities suggest a possible precursor-product relationship between the two carboxylester lipase forms.


Asunto(s)
Hidrolasas de Éster Carboxílico/aislamiento & purificación , Isoenzimas/aislamiento & purificación , Páncreas/enzimología , Esterol Esterasa/aislamiento & purificación , Secuencia de Aminoácidos , Aminoácidos/análisis , Animales , Carbohidratos/análisis , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Ácidos Grasos/análisis , Peso Molecular , Especificidad por Sustrato , Porcinos
9.
J Med Chem ; 22(3): 233-7, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-423204

RESUMEN

N-(5'-Phosphopyridoxyl) derivatives of several aromatic amino acids have been prepared by conventional methods and tested as inhibitors of mouse liver L-3,4-dihydroxyphenylalanine (Dopa) decarboxylase (EC 4.1.1.26; L-aromatic-amino-acid decarboxylase). The L-tyrosine, L-phenylalanine, and DL-2-hydroxyphenylalanine derivatives were effective inhibitors at concentrations of 10(-5) M. Because of the spontaneous formation of a tetrahydroisoquinoline cyclic condensation product with pyridoxal phosphate (Pictet--Spengler reaction), the Dopa derivative could not be prepared by the usual procedures. The synthesis of the desired N-(5'-phosphopyridoxyl)-Dopa was accomplished using selective blocking--deblocking methods; its properties are described. This proved to be the most effective inhibitor of those tested. Neither the tetrahydroisoquinoline of L-Dopa and pyridoxal phosphate nor the N-(5'-deoxypyridoxyl)-Dopa was an effective inhibitor of Dopa decarboxylase. These coenzyme amino acid adducts are suggested to act as stage inhibitors of the enzyme.


Asunto(s)
Inhibidores de Descarboxilasas de Aminoácidos Aromáticos , Dihidroxifenilalanina/análogos & derivados , Hígado/enzimología , Aminoácidos/farmacología , Animales , Dihidroxifenilalanina/síntesis química , Dihidroxifenilalanina/farmacología , Técnicas In Vitro , Cinética , Ratones
10.
Obstet Gynecol ; 60(4): 413-6, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6750473

RESUMEN

After double-blind controlled studies demonstrated cefamandole nafate irrigation of the uterus during cesarean section to be effective in reducing the rate of endomyometritis, antibiotic irrigation was adopted as a standard procedure at Tripler Army Medical Center. The present study analyzes the outcome in patients undergoing cesarean section before (comparison group) and after (treatment group) routine use of antibiotic irrigation began. The incidence of endomyometritis in 100 patients from the comparison group was 20% and in 298 patients from the treatment group 1.7% (P less than .0001). Serum analysis for cefamandole nafate demonstrated little systemic absorption of the antibiotic. Cefamandole nafate intrauterine irrigation at cesarean section effectively prevents endomyometritis.


Asunto(s)
Cefamandol/administración & dosificación , Cefalosporinas/administración & dosificación , Cesárea/efectos adversos , Endometritis/prevención & control , Cuidados Intraoperatorios , Infección Puerperal/prevención & control , Irrigación Terapéutica , Adulto , Cefamandol/análogos & derivados , Cefamandol/sangre , Ensayos Clínicos como Asunto , Método Doble Ciego , Endometritis/etiología , Femenino , Humanos , Embarazo , Premedicación
11.
J Orthop Res ; 9(2): 275-83, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1704056

RESUMEN

To study the distribution of cells in the surface layer of articular cartilage, rabbit hip and knee specimens were stained with silver and studied by scanning electron microscopy (SEM). The cartilage was treated en bloc using the Gomori methenamine silver technique, which stains the nuclei of exposed cells with reduced silver. The intact surface was then studied with a binocular microscope and SEM in the backscatter mode Only those cells within 30 microns of the surface stained, permitting that population to be imaged selectively. Depressions in the surface were related to groups of cells in clusters or rows bounded by collagen fibers. This study demonstrates the effectiveness of backscatter imaging in the study of chondrocytes. The relationship between surface contours and underlying cells is more complex than previously described.


Asunto(s)
Cartílago Articular/ultraestructura , Animales , Cartílago Articular/citología , Microscopía Electrónica de Rastreo , Conejos , Plata , Coloración y Etiquetado
12.
J Stud Alcohol ; 52(2): 148-55, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2016875

RESUMEN

The accurate measurement of alcohol consumption in natural environments is a focal empirical issue in studies of the determinants of drinking. Four studies investigated agreement between subject and collateral questionnaire reports of drinking by adults over age 60 years (N = 83), and three of these studies also assessed agreement between daily subject and collateral prospective reports of subject drinking over 4 (Study 2) or 12 (Studies 3 and 4) week intervals. Subject and collateral questionnaire reports were significantly correlated. Excellent agreement was found for the group of subjects for self-monitoring reports of the number of drinking days and quantity of alcohol consumption per day, including reports of the temporal patterning of consumption, but variability in agreement existed across subject-collateral pairs. The discussion focuses on the conditions conductive to accurate measurement and on the importance of investigating predictor variables of individual differences in the accuracy of verbal reports of alcohol consumption.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Recuerdo Mental , Revelación de la Verdad , Anciano , Consumo de Bebidas Alcohólicas/epidemiología , Alcoholismo/epidemiología , Alcoholismo/psicología , Sesgo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medio Social
13.
Addict Behav ; 14(6): 655-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2618849

RESUMEN

The relationship between three questionnaire measures of alcohol consumption and self-monitoring reports of drinking in the natural environment was investigated in 83 normal drinkers over 60 years of age. Following questionnaire administration subjects recorded their alcohol consumption each day for up to three months. Collaterals verified subjects' self-monitoring reports. Questionnaire scores and self-monitoring reports of frequency and quantity of alcohol consumption were generally well correlated. Regression analyses showed the Questionnaire Measure of Habitual Alcohol Use to be the best predictor of both drinking frequency and quantity. Measurement issues related to the use of verbal reports of alcohol consumption with elderly drinkers are discussed.


Asunto(s)
Anciano/psicología , Consumo de Bebidas Alcohólicas/psicología , Alcoholismo/psicología , Femenino , Identidad de Género , Humanos , Masculino , Calidad de Vida , Factores de Riesgo , Revelación de la Verdad
14.
J Reprod Med ; 30(11): 841-8, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4078817

RESUMEN

Premature rupture of the membranes remains a significant problem area in obstetrics. When the fetal lung maturity is inadequate and there is no evidence of intrauterine infection, a delay in delivery is recommended. When fetal lung maturity is expected or documented, lengthy delays in delivery should be avoided. Assays for phosphatidylglycerol in amniotic fluid collected from the vagina are most helpful in determining the maturity status. Therapeutic agents to accelerate lung maturity, stop labor or prevent infections must be considered investigational when used during the latency phase of premature rupture of the membranes.


Asunto(s)
Rotura Prematura de Membranas Fetales/terapia , Antibacterianos/uso terapéutico , Cesárea , Corioamnionitis/terapia , Terapia Combinada , Femenino , Rotura Prematura de Membranas Fetales/diagnóstico , Madurez de los Órganos Fetales/efectos de los fármacos , Humanos , Recién Nacido , Pulmón/embriología , Trabajo de Parto Prematuro/prevención & control , Embarazo , Síndrome de Dificultad Respiratoria del Recién Nacido/prevención & control , Riesgo , Esteroides/uso terapéutico , Infecciones Estreptocócicas/terapia
15.
Artículo en Inglés | MEDLINE | ID: mdl-18290177

RESUMEN

The use of surface acoustic waves in a scanning laser acoustic microscope for the characterization of the mechanical or acoustic properties of thin films deposited on piezoelectric substrates is demonstrated. Quantitative measurements of mass loading effects of 5000-A-thick tungsten films deposited on lithium niobate substrates were obtained using 100-MHz surface acoustic waves. No information about the tungsten film could be obtained using 100-MHz compressional waves. Methods of generating surface waves on nonpiezoelectric materials so that this technique could be used on arbitrary substrates are discussed.

20.
Scand J Rheumatol Suppl ; 82: 25-32, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2534706

RESUMEN

Among bone and joint diseases, frequent causes of disability include (a) fractures from falls and osteoporosis, (b) osteoarthritis of hips, knees, and lumbar spine, (c) painful feet, (d) back pain, and (e) intractable rheumatoid arthritis. Risk factors for falling may arise from factors intrinsic to the patient and from hazards in the environment. The prevention and management of osteoporosis are controversial. Most experts endorse the use of estrogens in postmenopausal women and the need for continuing physical activity, particularly walking, in both elderly men and women. To preserve independent living, conservative management of osteoarthritis of hip, knee, and low back consists of properly balancing rest, non-weight-bearing exercises, and the use of walking aids. In rheumatoid arthritis, the clinician should emphasize (a) exercises to maintain range of motion and (b) muscle strength, both to prevent flexion contractures and to maintain the ability to carry on activities of daily living.


Asunto(s)
Personas con Discapacidad , Trastornos del Movimiento/prevención & control , Accidentes por Caídas , Anciano , Envejecimiento/fisiología , Artritis Reumatoide/terapia , Dorso , Enfermedades del Pie/prevención & control , Fracturas Óseas/etiología , Fracturas Óseas/prevención & control , Estado de Salud , Articulación de la Cadera , Humanos , Articulación de la Rodilla , Osteoartritis/etiología , Osteoartritis/prevención & control , Osteoporosis/complicaciones , Osteoporosis/terapia , Dolor/prevención & control , Enfermedades de la Columna Vertebral/etiología , Enfermedades de la Columna Vertebral/prevención & control , Estrés Mecánico
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