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1.
Science ; 183(4130): 1194-7, 1974 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-17789221

RESUMEN

High-frequency (5 to 40 millihertz) induced lunar magnetic fields, observed at the Apollo 15 site near the southeastern boundary of Mare Imbrium and the southwestern boundary of Mare Serenitatis, show a strong tendency toward linear polarization in a direction radial to the Imbrium basin and circumferential to the Serenitatis basin, a property that could be indicative of a possible regional influence on the induction.

2.
Science ; 172(3980): 256-8, 1971 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-17847243

RESUMEN

A comparison has been made of the interplanetary magnetic field as measured both by Apollo 12 on the lunar surface and by Explorer 35 in orbit around the moon. Two examples are given, one of a step change in the field vector and another of a sinusoidally varying field. A large response measured on the surface is attributed to confinement of the induced field lines between the streaming solar plasma and the high-conductivity interior. A steep bulk electrical conductivity gradient in the lunar crust is implied, with a confining layer roughly 100 kilometers deep.

3.
J Clin Invest ; 76(2): 439-45, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4031059

RESUMEN

The goals of this study were to isolate and characterize the nonlipid matrix of human cholesterol gallstones. The lipid portion of gallstones was dissolved in ethanol/ether, leaving an insoluble, granular, brown-black matrix that constituted 12.5% of solitary large stones and 3.5% of multiple small stones. The matrix was partially solubilized by sonication and studied by exclusion gel chromatography and density gradient ultracentrifugation. On Sepharose 2B column chromatography, bile pigment eluted with glycoprotein in the void volume, suggesting the presence of a high molecular weight complex (Mr greater than 2 X 10(6)). The identity of mucin in this complex was confirmed by its typical buoyant density during ultracentrifugation. The major bile pigments in the matrix were identified as bilirubin (84%) and bilirubin monoglucuronide (15%) by thin-layer chromatography. Because of their ability to solubilize mucin-type glycoproteins, we tested the ability of the reducing agents 2-mercaptoethanol (2ME) and N-acetylcysteine (NAcCys) to solubilize gallstone matrix. Both reducing agents caused a two- to threefold enhancement of matrix dissolution after 4 d compared to aqueous buffer alone (P less than 0.01). Sepharose 2B chromatography revealed that 2ME released a high molecular weight mucin-bilirubin complex as well as unbound pigment from the insoluble matrix. We also tested the effect of reducing agents on dissolution of matched cholesterol gallstones by monooctanoin, a cholesterol solvent. Both 2ME and NAcCys significantly accelerated gallstone dissolution in monooctanoin. Matched human cholesterol stones (n = 10) incubated for 4 d in monooctanoin plus either 2ME or NAcCys (1 M final concentration) weighed approximately half as much (P less than 0.01 for each) as stones incubated in monooctanoin alone. This study describes, for the first time, the isolation of a bilirubin-mucin complex in the insoluble matrix of human cholesterol gallstones. The ability of reducing agents to dissolve the matrix and thereby accelerate gallstone dissolution by monooctanoin in vitro may be relevant to gallstone dissolution in humans.


Asunto(s)
Bilirrubina/análisis , Colesterol/análisis , Vesícula Biliar/análisis , Mucinas/análisis , Acetilcisteína/farmacología , Caprilatos , Centrifugación por Gradiente de Densidad , Cromatografía en Gel , Cromatografía en Capa Delgada , Glicéridos/farmacología , Humanos , Mercaptoetanol/farmacología , Peso Molecular , Solubilidad , Sonicación
4.
Mol Cell Biol ; 10(6): 3268-71, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2160598

RESUMEN

Retroviral vectors were used to transfer genes efficiently into rat and dog myoblasts in primary cultures under conditions which permitted the transduced myoblasts to differentiate into myotubes expressing the transferred genes. The transduced myotubes expressed normal markers of differentiation and were morphologically indistinguishable from uninfected myotubes. Retroviral vector-mediated gene transfer was also used to correct a genetic enzyme deficiency in mutant canine muscle cells.


Asunto(s)
Músculos/citología , Mutación , Retroviridae/genética , Transfección , Animales , Diferenciación Celular , Células Cultivadas , Perros , Feto , Genes Bacterianos , Glucuronidasa/deficiencia , Glucuronidasa/genética , Kanamicina Quinasa , Fosfotransferasas/genética , Ratas , Ratas Endogámicas
5.
J Clin Endocrinol Metab ; 41(1): 199-202, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-807592

RESUMEN

The cytochemical bioassay is able to detect minute amounts of thyroteopin and thyroid stimulating immunoglobulins. Estimations of serum TSH by the cytochemical bioassay are in good agreement with values obtain by radioimmunoassay. In untreated hyperthyroid patients with Graves' disease the TSH levels are significantly lower than in control subjects. Thyroid stimulating immunoglobulins showed a delayed time corse of action in the bioassy and this provided a voncenient method of distinguishing between the two thyroid stimulators.


Asunto(s)
Tirotropina/sangre , Animales , Bioensayo , Enfermedad de Graves/sangre , Enfermedad de Graves/inmunología , Cobayas , Histocitoquímica , Humanos , Fragmentos Fab de Inmunoglobulinas , Inmunoglobulina G , Cinética , Métodos , Radioinmunoensayo , Glándula Tiroides/efectos de los fármacos , Tirotropina/farmacología , Hormona Liberadora de Tirotropina/farmacología
6.
Gene ; 168(2): 275-6, 1996 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-8654960

RESUMEN

The canine muscle-type-phosphofructokinase-encoding gene (M-PFK) was sequenced by using a combination of cDNA cloning and RT-PCR amplification. The canine M-PFK sequence shares 88 and 90% identity with rabbit and human M-PFK, respectively. The canine ORF was determined to be 6-bp longer than either human or rabbit M-PFK due to a 6-bp insertion at the end of exon 13.


Asunto(s)
Perros/genética , Isoenzimas/genética , Músculo Esquelético/enzimología , Fosfofructoquinasa-1/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Elementos Transponibles de ADN , ADN Complementario , Biblioteca de Genes , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Conejos , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
7.
Biotechniques ; 27(2): 356-61, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10457844

RESUMEN

A sensitive assay for adenovirus quantitation in vitro was developed using the flow microsphere immunoassay (FMIA) approach. Polystyrene microspheres were covalently coated with purified anti-adenoviral antibodies and incubated with virus-containing samples. After incubation, the samples were stained with DNA-specific fluorescent dyes, and microsphere-associated fluorescence was quantitated with a flow cytometer. The adsorption of virus to microspheres was examined under different experimental conditions. The flow cytometric assay was determined to be as accurate in detecting adenovirus as titering on 293 cells. The proposed method can be used to quantify virus in viral stocks and in biological samples.


Asunto(s)
Adenoviridae/aislamiento & purificación , Inmunoensayo/métodos , Adenoviridae/inmunología , Adsorción , Anticuerpos Monoclonales/inmunología , Sitios de Unión , Escherichia coli , Colorantes Fluorescentes/química , Microesferas , Tiazoles/química , Factores de Tiempo
8.
J Expo Anal Environ Epidemiol ; 10(6 Pt 2): 776-88, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11138670

RESUMEN

In support of a study to relate developmental and cognitive effects with prenatal exposure to selected environmental toxicants, we developed and applied an analytical method to determine the concentration of two persistent pesticides, hexachlorobenzene (HCB) and p,p'-dichlorodiphenyldichloroethylene (DDE), and 32 specific polychlorinated biphenyl (PCB) congeners in 316 umbilical cords taken in 1986-1987 from women of the Faroe Islands. The analytical method consisted of homogenization of the cords, partitioning, microsilica gel column chromatography for clean-up, and dual-column capillary gas chromatography (DB-5 and DB-1701) with electron capture detection. Several quality control parameters were followed to monitor the performance of the method. Important criteria used before reporting unknown data were the recovery of in vitro-spiked analytes from a bovine umbilical cord (BUC) and the percentage lipid obtained for a Certified Reference Material (CRM)-350 of mackerel oil (MO). Recoveries of analytes that had been spiked at two concentration ranges (0.26-0.95 ng/g whole weight; 0.35-2.42 ng/g whole weight) into bovine cords ranged from 38.5% to 158% and from 50.4% to 145%, respectively, with a median recovery of 77.7%. Measurement of the percentage lipid for CRM-350 ranged from 73.8% to 107% with a median lipid value of 96.0%. The most prevalent analytes detected (%) in unknown umbilical cords were HCB (100), DDE (100), Ballschmiter/Zell PCBs 153 (100), 138 (98), 180 (98), 170 (93), 118 (88), 187 (86), and 146 (83), with corresponding median concentrations (ng/g whole weight) of 0.17, 1.19, 0.38, 0.30, 0.17, 0.11, 0.12, 0.09, and 0.07, respectively. Total PCB--sum of all measurable PCB congeners--had a median concentration of 1.37 ng/g whole weight. The analytes, which were very low in lipid content were also quantified on a lipid-adjusted basis, which provided an analytical challenge in these umbilical cord samples. The gravimetrically measured lipids in the human specimens ranged from 0.01% to 1.43% (median of 0.18%). In the pooled BUCs, our lipid measurements varied from 0.05% to 0.33% with a median value of 0.13%. The utility of using the umbilical cord as a matrix to assess in utero exposure to persistent environmental pollutants, compared with the use of umbilical cord blood or mother's blood, is worthy of debate.


Asunto(s)
Contaminantes Ambientales/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Efectos Tardíos de la Exposición Prenatal , Cordón Umbilical/química , Adulto , Animales , Bovinos , Cromatografía de Gases/métodos , Exposición a Riesgos Ambientales , Contaminantes Ambientales/efectos adversos , Femenino , Humanos , Recién Nacido , Lípidos/química , Masculino , Plaguicidas/efectos adversos , Bifenilos Policlorados/efectos adversos , Embarazo , Sensibilidad y Especificidad
9.
Am J Med Sci ; 286(1): 37-9, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6869416

RESUMEN

A polymorphonuclear pleocytosis of the cerebrospinal fluid is an occasional occurrence following hemorrhagic cerebral infarction. Because the peak of this neutrophilic reaction occurs 3 to 4 days after the event it is usually missed and not widely appreciated. We have described an example of this response in an attempt to alert physicians to an important differential diagnostic consideration when faced with a neutrophilic CSF pleocytosis.


Asunto(s)
Hemorragia Cerebral/líquido cefalorraquídeo , Infarto Cerebral/líquido cefalorraquídeo , Neutrófilos/citología , Hemorragia Cerebral/etiología , Infarto Cerebral/etiología , Femenino , Humanos , Embolia y Trombosis Intracraneal/líquido cefalorraquídeo , Embolia y Trombosis Intracraneal/complicaciones , Persona de Mediana Edad
10.
Avian Dis ; 43(2): 251-61, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10396638

RESUMEN

Virulence mechanisms of six isolates of Mycoplasma synoviae (MS), previously classified as pathogenic (K1968), moderately pathogenic (WVU 1853, K1858, 92D8034, and F10-2AS), and mildly pathogenic (FMT) in chickens, were examined. The most virulent isolate, K1968, had been found to invade systematically and produce lesions following eye-drop inoculation. In the present study, all isolates were evaluated for presence of a possible cytadhesin and for functional attachment to host cells as indicated by hemagglutination and hemadsorption. Three representative isolates, K1968, 92D8034, and FMT, were evaluated for attachment and colonization in cultured chick tracheal rings and tendon cell monolayers by direct transmission electron microscopic examination and by quantitative polymerase chain reaction assay. Ciliostasis was compared in tracheal organ culture. Previously found differences in pathogenicity of these isolates for chickens could not be explained as differences in attachment and were only partially explained by differences in colonization. Pathogenicity of the most virulent isolate of MS was suspected to be multifactorial, involving attachment and colonization of the upper respiratory tract plus additional unidentified factors associated with systemic invasion and lesion production.


Asunto(s)
Infecciones por Mycoplasma/veterinaria , Mycoplasma/patogenicidad , Enfermedades de las Aves de Corral/microbiología , Animales , Western Blotting/veterinaria , Células Cultivadas , Pollos , Hemabsorción , Hemaglutinación , Microscopía Electrónica/veterinaria , Mycoplasma/clasificación , Reacción en Cadena de la Polimerasa/veterinaria , Conejos , Tendones/microbiología , Tráquea/microbiología
11.
J Am Vet Med Assoc ; 201(10): 1569-71, 1992 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-1289336

RESUMEN

A 3-year-old female American Cocker Spaniel with a chronic hemolytic disorder and hemolytic crises was found to have M-type phosphofructokinase deficiency. This inherited erythroenzymopathy and myopathy is commonly diagnosed in English Springer Spaniels, but the family study of this Cocker Spaniel, although supporting an autosomal recessive mode of inheritance, did not reveal any English Springer Spaniel ancestors. Molecular genetic studies did, however, identify the same mutation in this dog as we previously reported in the English Springer Spaniel breed, suggesting that this mutation originated prior to the separation of these 2 breeds.


Asunto(s)
Anemia Hemolítica/veterinaria , Enfermedades de los Perros/genética , Eritrocitos/enzimología , Fosfofructoquinasa-1/deficiencia , Anemia Hemolítica/enzimología , Anemia Hemolítica/genética , Animales , Cruzamiento , Enfermedades de los Perros/sangre , Enfermedades de los Perros/enzimología , Perros , Femenino , Enfermedades Musculares/enzimología , Enfermedades Musculares/genética , Enfermedades Musculares/veterinaria , Mutación , Linaje , Fosfofructoquinasa-1/sangre , Fosfofructoquinasa-1/genética , Síndrome
12.
J Pediatr Ophthalmol Strabismus ; 24(5): 259-62, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3681615

RESUMEN

In Stargardt's disease, a gradual loss of vision may precede both the appearance of paracentral or peripheral retinal flecks as well as funduscopically obvious macular changes. This latency delayed a diagnosis of Stargardt's disease in a young girl who underwent neurologic testing for what eventually turned out to be a retinal problem. At one stage in evolution, when retinal flecks and only subtle changes in the maculae were present, a diagnosis of a pure form of fundus flavimaculatus was considered likely. When severe granularity and atrophy of the maculae later developed in the presence of the retinal flecks, a more appropriate diagnosis of Stargardt's disease was made. As the degenerative and atrophic changes in the maculae became more pronounced in early adulthood, the flavimacular retinal flecks had all but disappeared.


Asunto(s)
Degeneración Macular/diagnóstico , Niño , Desarrollo Infantil , Femenino , Fondo de Ojo , Cefalea/etiología , Humanos , Degeneración Macular/clasificación , Degeneración Macular/patología , Degeneración Macular/fisiopatología , Trastornos por Fotosensibilidad/etiología , Retina/patología , Escotoma/etiología , Trastornos de la Visión/etiología , Visión Ocular , Campos Visuales
13.
Scott Med J ; 29(3): 150-3, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6398512

RESUMEN

Type 1 diabetics receiving once (Group 1, n = 72) and twice (Group 2, n = 48) daily subcutaneous injections of conventional beef insulin were compared, on a cross-sectional basis, in respect of insulin antibody binding by serum and total glycosylated haemoglobin (HbA1). Patients in Group 1 had higher insulin antibody binding (25.2 +/- 15.8% vs 17.0 +/- 13.9%; p less than 0.01) and higher HbA1 levels (12.5 +/- 2.0% vs 11.0 +/- 1.8%; p less than 0.001) than patients in Group 2. An inverse correlation (tau = -0.28, p less than 0.01) was observed between HbA1 and insulin antibody binding in C-peptide non-secretors of Group 1 but not in Group 1 C-peptide secretors, nor in C-peptide secretors and/or non-secretors of Group 2. It is suggested that in Type 1 diabetics who receive a single daily insulin injection and who have no endogenous insulin secretion, insulin antibodies may aid glycaemic control by prolonging insulin action.


Asunto(s)
Anticuerpos/inmunología , Diabetes Mellitus Tipo 1/sangre , Hemoglobina Glucada/metabolismo , Insulina/inmunología , Adulto , Animales , Glucemia/metabolismo , Péptido C/metabolismo , Bovinos , Estudios Transversales , Diabetes Mellitus Tipo 1/inmunología , Femenino , Humanos , Masculino
14.
J Small Anim Pract ; 42(6): 298-300, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11440399

RESUMEN

Phosphofructokinase (PFK) deficiency is an autosomal recessive inherited disorder in dogs causing haemolytic crises and exertional myopathy. The clinical signs may be confused with those of recurrent immune-mediated haemolytic anaemia. The deficiency has been commonly observed in field trial (working) English springer spaniels (ESSPs), but also in the conformation line of ESSPs in the USA over the past two decades. This report documents the first family of ESSPs found with PFK deficiency in Europe. Two related adult ESSPs in Denmark had intermittent signs of pigmenturia after exercise (hunting) and had evidence of a regenerative haemolytic anaemia. Based upon DNA sequencing data, both dogs had the previously described nonsense point mutation in the muscle-type PFK gene (delta2228G-->A). Study of 17 related family members using a simple and accurate PFK-DNA test revealed one additional PFK-deficient dog (with minor exercise intolerance), nine carriers and seven normal (or 'clear') ESSPs. Recently, the authors have also identified PFK carriers and affected ESSPs in the UK. Screening for PFK deficiency is recommended for ESSPs with suspicious clinical signs and before using any for field trials or breeding in order to prevent the further spread of this hereditary disorder.


Asunto(s)
Anemia Hemolítica Congénita/veterinaria , Enfermedades de los Perros/diagnóstico , Enfermedad del Almacenamiento de Glucógeno Tipo VII/veterinaria , Fosfofructoquinasa-1/deficiencia , Anemia Hemolítica Congénita/etiología , Animales , Cruzamiento , Diagnóstico Diferencial , Enfermedades de los Perros/genética , Perros , Electroforesis en Gel de Poliacrilamida/veterinaria , Eritrocitos/enzimología , Femenino , Enfermedad del Almacenamiento de Glucógeno Tipo VII/complicaciones , Enfermedad del Almacenamiento de Glucógeno Tipo VII/diagnóstico , Masculino , Linaje , Fosfofructoquinasa-1/sangre , Fosfofructoquinasa-1/genética , Mutación Puntual , Reacción en Cadena de la Polimerasa/veterinaria
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