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1.
J Hand Surg Eur Vol ; 34(1): 85-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19129364

RESUMEN

Flexor tendon divisions in Zone 1 need to be re-inserted to the distal phalanx. This paper describes the Transverse Intraosseous Loop Technique (TILT) of re-inserting the profundus tendon to the distal phalanx in which an internally placed suture is looped through the bone and tendon interface. It provides a strong repair, which permits the desired tensioning and can be performed in children. Ten of 12 patients' re-insertions using this technique achieved full recovery while two developed fixed flexion contractures.


Asunto(s)
Traumatismos de los Dedos/cirugía , Falanges de los Dedos de la Mano/cirugía , Técnicas de Sutura , Traumatismos de los Tendones/cirugía , Adolescente , Adulto , Hilos Ortopédicos , Niño , Preescolar , Femenino , Traumatismos de los Dedos/fisiopatología , Estudios de Seguimiento , Fuerza de la Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Fuerza de Pellizco/fisiología , Complicaciones Posoperatorias/fisiopatología , Rango del Movimiento Articular/fisiología , Reoperación , Traumatismos de los Tendones/fisiopatología
2.
Br J Plast Surg ; 57(1): 83-5, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14672682

RESUMEN

Granular cell tumour of the glans penis is a rare finding with only two other cases reported. This case highlights the importance of achieving the correct diagnosis, as differing excision margins are critical, particularly in this site.


Asunto(s)
Tumor de Células Granulares/patología , Neoplasias del Pene/patología , Adolescente , Tumor de Células Granulares/cirugía , Humanos , Masculino , Neoplasias del Pene/cirugía
3.
Plant Dis ; 88(12): 1341-1346, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30795195

RESUMEN

The distribution of three Ophiosphaerella spp. that cause spring dead spot (SDS) of bermudagrass was studied by sampling at 24 locations in the southeastern United States. O. korrae was isolated from 73% of the 204 bermudagrass cores collected and was the only SDS pathogen recovered at most sites. O. herpotricha was isolated at three locations in Kentucky and one in North Carolina, and O. narmari was found at two locations in North Carolina. Most O. korrae isolates collected from Alabama, Kentucky, Mississippi, Tennessee, and Virginia clustered in an amplified fragment length polymorphism group (AFLP group II) that was distinct from Kentucky bluegrass isolates collected throughout North America and similar to bermudagrass isolates from Kansas and Oklahoma (AFLP group I). A third AFLP group (III) consisting of bermudagrass isolates from Mississippi and Virginia was identified. Isolates representing AFLP groups II and III grew more rapidly on potato dextrose agar at 25 and 30°C than those in group I. O. korrae isolates differed in their aggressiveness to two bermudagrass cultivars in greenhouse studies, but these differences were not associated with AFLP group, location, or host from which the isolate was collected.

4.
Br J Plast Surg ; 56(2): 145-9, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12791359

RESUMEN

A large number of techniques have been described for the correction of prominent ears to improve the cosmetic outcome and reduce the complication rates. The procedure favoured by the senior author brings together a number of refinements, notably, percutaneous anterior scoring using a modified green needle, control over the degree of fold created and a simple but effective dressing. 114 consecutive patients underwent the correction of 214 ears, with a mean follow up of 3 years and 11 months (9 months to 9 years and 6 months). The senior author performed 100 of these procedures and supervised a senior trainee for the remainder. The mean patient age was 18 years 3 months (3 to 66 years). 57 males and 57 females. 56 general anaesthetic and 58 local anaesthetic. Post-operative complications were; haemorrhage, one ear (required a dressing change); infection, four ears (treated with antibiotics); hypertrophic scarring, two ears which settled (no keloid); recurrence one ear (repeated surgery); continued prominence six ears (two had repeated surgery). No prominent sutures, no anterior skin necrosis, no visible irregularity of the anterior surface of the cartilage and no haematoma occurred. We feel that the low complication rate is due to maximising the advantages and minimising the disadvantages of the different techniques and refinements. We recommend this technique for the routine correction of prominent ears due to a poorly formed antihelical fold or deep conchal bowl.


Asunto(s)
Oído Externo/anomalías , Procedimientos de Cirugía Plástica/métodos , Adolescente , Adulto , Niño , Preescolar , Oído Externo/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del Tratamiento
5.
Crop Sci ; 42(1): 197-201, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11756274

RESUMEN

Visual evaluation of turfgrass quality is a subjective process that requires experienced personnel. Optical sensing of plant reflectance provides objective, quantitative turf quality evaluation and requires no turf experience. This study was conducted to assess the accuracy of optical sensing for evaluating turf quality, to compare the rating consistency among human evaluators and optical sensing, and to develop a model that describes a relationship between optically sensed measurements and visual turf quality. Visual evaluations for turf color, texture, percent live cover (PLC), and optically sensed measurements were collected on the National Turfgrass Evaluation Program (NTEP) tall fescue (Festuca arundinacea Schreb) and creeping bentgrass (Agrostis palustris Huds.) trials at Stillwater, OK. Measurements were made monthly for 12 consecutive months from June 1999 through May 2000. Red (R) and near infrared (NIR) reflectance were collected with sensors and converted to normalized difference vegetative indices (NDVI). The NDVI were closely correlated with visual evaluations for turf color, moderately correlated with percent live cover (PLC), and independent of texture. Measurements of turf color and PLC were evaluated more consistently with optical sensors than by visual ratings. Normalized difference vegetation index (Y) could be reliably predicted by the following generalized model for turf color (X) and PLC (Z): Y = B(0) + B(1)log10X + B(2)Z(3). Optical sensing provided fast, reliable turf assessment and deserves consideration as a supplemental or replacement technique for evaluating turf quality.

6.
Plant Dis ; 86(7): 764-768, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30818574

RESUMEN

Numerous genera of plant-parasitic nematodes are frequently present at high populations in golf course putting greens. The objectives of this research were to identify and quantify plant-parasitic nematodes from Oklahoma bentgrass putting greens and to characterize specific soil physical and chemical features and management factors that may account for differences in or associated with the observed nematode populations. In the fall of 2000, nematodes were identified from 99 individual bentgrass putting greens sampled from 46 different locations in Oklahoma. In addition to green age and bentgrass cultivar; soil pH, nitrate-nitrogen (NO3-N), plant-available phosphorus and potassium, organic matter (OM), bulk density, and particle size distribution were determined for each green. Expenditures on management activities, including fertilizer, herbicide, fungicide, and insecticide, were determined for 20 of the sampled courses and compared with nematode populations. Nematodes from seven genera were found in Oklahoma greens, with Criconemella spp. being the most common. Paratrichodorus spp., Tylenchorhynchus spp., and Helicotylenchus spp. also were common. The logarithmic populations of all nematodes combined increased with greater green age (r = 0.37). A negative relationship was observed between soil bulk density and all nematodes combined (r = -0.29). Soil NO3-N, plant-available K, and OM increased with combined logarithmic populations of all plant parasitic nematodes (r = 0.23, 0.28, and 0.37, respectively). A four-factor model accounted for 75% of the total variation in the data and permitted groupings of all variables into four uncorrelated factors. Total logarithmic nematode populations increased with fungicide and herbicide expenditures (r = 0.31). This study suggests that populations of plant-parasitic nematodes may be influenced by the putting green abiotic soil environment and possibly indirectly by management practices on putting greens.

7.
Brain Res ; 914(1-2): 81-91, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11578600

RESUMEN

gamma-Aminobutyric acid (GABA) synthesis in the brain is mediated by two major isoforms of glutamic acid decarboxylase, GAD(65) and GAD(67). The contribution of these isoforms to GABA synthesis flux (V(GAD)) is not known quantitatively. In the present study we compared V(GAD) in cortex of control and vigabatrin-treated rats under alpha-chloralose/70% nitrous oxide anesthesia, with total GAD activity and GAD isoform composition (GAD(65) and GAD(67)) measured by enzymatic assay and quantitative immunoblotting. V(GAD) was determined by re-analysis of 13C NMR data obtained ex vivo and in vivo during infusions of [1-13C]glucose using an extension of a model of glutamate-glutamine cycling that included a discrete GABAergic neuronal compartment with relevant interconnecting fluxes. V(GAD) was significantly lower in vigabatrin-treated rats (0.030-0.05 micromol/min per g, P<0.003) compared to the non-treated control group (0.10-0.15 micromol/min per g). The 67-70% decrease in V(GAD) was associated with a 13% decrease in total GAD activity (P=0.01) and a selective 44+/-15% decrease in GAD(67) protein (from 0.63+/-0.10 to 0.35+/-0.08 microg protein/mg tissue, P<0.05); GAD(65) protein was unchanged. The reduction in GAD(67) protein could account for a maximum of approximately 65% of the decrease in V(GAD) in vigabatrin-treated animals suggesting that inhibition of GAD(65) must have also occurred in these experiments, although product inhibition of GAD(67) by increased GABA could play a role. GAD(67) could account for 56-85% of cortical GABA synthesis flux under basal conditions and the entire flux after vigabatrin treatment.


Asunto(s)
Corteza Cerebral/enzimología , Regulación hacia Abajo/fisiología , Glutamato Descarboxilasa/metabolismo , Isoenzimas/metabolismo , Neuronas/enzimología , Ácido gamma-Aminobutírico/biosíntesis , 4-Aminobutirato Transaminasa/efectos de los fármacos , 4-Aminobutirato Transaminasa/metabolismo , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Radioisótopos de Carbono/farmacocinética , Corteza Cerebral/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Glutamato Descarboxilasa/efectos de los fármacos , Ácido Glutámico/metabolismo , Glutamina/metabolismo , Isoenzimas/efectos de los fármacos , Cinética , Masculino , Neuronas/efectos de los fármacos , Isoformas de Proteínas/efectos de los fármacos , Isoformas de Proteínas/metabolismo , Ratas , Ratas Sprague-Dawley , Vigabatrin/farmacología
8.
Arch Biochem Biophys ; 392(2): 333-40, 2001 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-11488610

RESUMEN

Cofactor and tryptophan accessibility of the 65-kDa form of rat brain glutamate decarboxylase (GAD) was investigated by fluorescence quenching measurements using acrylamide, I-, and Cs+ as the quenchers. Trp residues were partially exposed to solvent. I- was less able and Cs+ was more able to quench the fluorescence of Trp residues in the holoenzyme of GAD (holoGAD) than the apoenzyme (apoGAD). The fraction of exposed Trp residues were in the range of 30-49%. In contrast, pyridoxal-P bound to the active site of GAD was exposed to solvent. I- was more able and Cs+ was less able to quench the fluorescence of pyridoxal-P in holoGAD. The cofactor was present in a positively charged microenvironment, making it accessible for interactions with anions. A difference in the exposure of Trp residues and pyridoxal-P to these charged quenchers suggested that the exposed Trp residues were essentially located outside of the active site. Changes in the accessibility of Trp residues upon pyridoxal-P binding strongly supported a significant conformational change in GAD. Fluorescence intensity measurements were also carried out to investigate the unfolding of GAD using guanidine hydrochloride (GdnHCl) as the denaturant. At 0.8-1.5 M GdnHCl, an intermediate step was observed during the unfolding of GAD from the native to the denatured state, and was not found during the refolding of GAD from the denatured to native state, indicating that this intermediate step was not a reversible process. However, at >1.5 M GdnHCl for holoGAD and >2.0 M GdnHCl for apoGAD, the transition leading to the denatured state was reversible. It was suggested that the intermediate step involved the dissociation of native dimer of GAD into monomers and the change in the secondary structure of the protein. Circular dichroism revealed a decrease in the alpha-helix content of GAD from 36 to 28%. The unfolding pattern suggested that GAD may consist of at least two unfolding domains. Unfolding of the lower GdnHCl-resisting domain occurred at a similar concentration of denaturant for apoGAD and holoGAD, while unfolding of the higher GdnHCl-resisting domain occurred at a higher concentration of GdnHCl for apoGAD than holoGAD.


Asunto(s)
Encéfalo/enzimología , Glutamato Descarboxilasa/química , Triptófano/química , Acrilamida/farmacología , Animales , Aniones , Sitios de Unión , Línea Celular , Cesio/farmacología , Dicroismo Circular , Dimerización , Relación Dosis-Respuesta a Droga , Guanidina/farmacología , Insectos , Yodo/farmacología , Iones , Cinética , Unión Proteica , Conformación Proteica , Desnaturalización Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Ratas , Espectrometría de Fluorescencia
9.
J Membr Biol ; 182(2): 135-46, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11447505

RESUMEN

Among different treatments assayed, a mix of a nonionic detergent (5% Tween-20) with 0.5 m NaCl was found to solubilize a large part of the calmodulin-dependent NAD+ kinase bound to the inner mitochondrial membrane. It also stimulated its activity by increasing 7 times the maximal velocity. Activity stimulation was also observed with phosphatidylcholine, phosphatidylethanolamine and with reductants (HSO3 and DTT). This solubilized NAD+ kinase and the calmodulin-dependent cytosoluble isoform displayed distinct molecular masses, as well as different kinetic parameters. We propose that solubilization of membrane-bound NAD+ kinase could occur in vivo in Avena sativa and could generate a soluble isoform.


Asunto(s)
Avena/enzimología , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Polisorbatos/farmacología , Calcio/farmacología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Calmodulina/farmacología , Proteínas de Unión a Calmodulina/farmacología , Fraccionamiento Celular , Cinética , Proteínas de la Membrana , Mitocondrias/metabolismo , Oxidación-Reducción , Fosfotransferasas (Aceptor de Grupo Alcohol)/efectos de los fármacos , Semillas , Cloruro de Sodio/farmacología , Tensoactivos/farmacología
10.
11.
Orthopedics ; 23(7): 707-11; discussion 711-2, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10917246

RESUMEN

This article reports the first available human retrieval data following the use of a new fixation system for tumor prostheses. The compliant prestress (CPS) fixation system obviates the need for long intramedullary stems. The CPS was designed to provide a stable, high-pressure, motion-free bone-implant interface that would prevent aseptic loosening and allow osseointegration at the bone-implant interface. At 10 months, the fourth patient in the human trial required amputation. Backscatter electron microscopy revealed a buttress of new bone had formed along 70% of the bone-metal interface, with excellent bony ingrowth (average: 42%) into the transverse, porous-coated titanium interface.


Asunto(s)
Neoplasias Femorales/patología , Neoplasias Femorales/cirugía , Recurrencia Local de Neoplasia/cirugía , Osteosarcoma/patología , Osteosarcoma/cirugía , Implantación de Prótesis/instrumentación , Terapia Recuperativa/métodos , Adolescente , Amputación Quirúrgica , Neoplasias Femorales/tratamiento farmacológico , Fémur/patología , Humanos , Masculino , Recurrencia Local de Neoplasia/patología , Oseointegración , Osteosarcoma/tratamiento farmacológico , Diseño de Prótesis , Implantación de Prótesis/métodos
12.
J Clin Neurophysiol ; 17(3): 331-5, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10928645

RESUMEN

The selection of which high-pass filter cutoff to use in P300 studies continues to be a serious methodological consideration. To determine whether there was an optimal range of bandpass widths-a range in which P300 voltage and latency would not show statistically significant differences-the authors recorded P300 responses to the auditory "oddball" paradigm from Cz and Pz electrodes in a group of eight healthy males. The authors used high-pass filter cutoffs of 0.01, 0.1, 0.3, and 1.0 Hz with low-pass filter cutoffs of 30 and 100 Hz and measured both P300 peak voltages and P300 integrated mean voltages at 12 bandpass settings. There were statistically significant differences in 7 out of 12 bandpass comparisons for P300 peak voltages and in 7 out of 12 bandwidth comparisons for P300 integrated mean voltages. For P300 latencies, there were statistically significant differences in 9 out of 12 bandwidth comparisons. Based on these results, the best recommendation, therefore, is that the high-pass filter be set no higher than 0.3 Hz.


Asunto(s)
Corteza Cerebral/fisiología , Electroencefalografía , Potenciales Relacionados con Evento P300/fisiología , Tiempo de Reacción/fisiología , Adulto , Artefactos , Humanos , Masculino , Valor Predictivo de las Pruebas , Valores de Referencia
13.
J Exp Bot ; 51(349): 1389-94, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10944152

RESUMEN

Freshly-harvested seeds of Avena sativa L. do not germinate when imbibed at temperatures higher than 25 degrees C. This high temperature dormancy is due to the seed coats, and to the low activities of glycolysis and the oxidative pentose phosphate pathway (OPP) in the embryo. The analysis by exclusion chromatography of soluble NADP(+) phosphatase activities of embryos revealed two isoforms: a 37 kDa isoform present in both dormant and after-ripened caryopses, and a second isoform, with an apparent molecular weight of 160 kDa, five times more active in embryos of dormant seeds than in the after-ripened ones, after 6 h of imbibition at 30 degrees C. Moreover, the activity of this 160 kDa isoform was three times less in embryos from dormant caryopses when they were grown at 10 degrees C, a permissive temperature for radicle protrusion. These results suggest a correlation between the activity of the 160 kDa NADP(+) phosphatase and the dormancy state of the caryopsis. The two isoforms differed in the pH required for optimal activity: pH 5.7 and 6.5 for the 37 kDa and the 160 kDa phosphatases, respectively. Furthermore, the 160 kDa NADP(+) phosphatase displayed a strong specificity for NADP(+), whereas the 37 kDa isoform was able to hydrolyse numerous other phosphorylated compounds.


Asunto(s)
Avena/enzimología , Nucleotidasas/metabolismo , Semillas/enzimología , Cromatografía por Intercambio Iónico , Técnicas de Cultivo , Fracciones Subcelulares/enzimología , Temperatura
14.
Arch Biochem Biophys ; 380(2): 285-93, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10933883

RESUMEN

To investigate ATP as a potential factor in the regulation of brain glutamate decarboxylase (GAD), the impact of ATP on the enzyme conformation and holoenzyme formation was investigated. ATP at 100 microM quenches fluorescence emission intensity of the holoenzyme of GAD (holoGAD) by 18% after a correction for the inner filter effect and enhances fluorescence steady-state polarization from 0.158 to 0. 183 when excited at 280 or 295 nm. These findings suggest that ATP moderately changes the microenvironment of one or more tryptophan or tyrosine residues in holoGAD and alters these residues from a more mobile state to a less mobile one. A moderate ATP-induced conformational change in holoGAD is also supported by the observations that ATP increases the thermal denaturation temperature of holoGAD by 2 degrees C, as derived from temperature-dependent fluorescence spectra, and decreases the alpha-helical content of holoGAD by 8-10%, as determined by circular dichroism. Moreover, ATP does not affect the keto-enol tautomerization of holoGAD and has little or no direct effect on its activity, implying that the ATP interacting domain in holoGAD is not at the active site. Kinetics studies, as demonstrated by stopped-flow fluorescence and UV/visible spectroscopy, demonstrate that formation of holoGAD involves two steps: a fast reaction forming an apoGAD-cofactor intermediate complex, followed by a slow reaction involving the conformational change in the intermediate complex. ATP reduces the rate constant of the fast step to one-third and decreases the rate of the slow step and the intermediate complex formation constant to 60% of their original values. The present data suggest that ATP may regulate the interconversion between apoGAD and holoGAD by interacting with apoGAD rather than holoGAD. By slowing down the rate of intermediate complex formation, ATP reduces the amount of holoGAD formed.


Asunto(s)
Adenosina Trifosfato/farmacología , Encéfalo/enzimología , Glutamato Descarboxilasa/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Apoenzimas/química , Apoenzimas/metabolismo , Dicroismo Circular , Glutamato Descarboxilasa/química , Holoenzimas/química , Holoenzimas/metabolismo , Técnicas In Vitro , Cinética , Conformación Proteica/efectos de los fármacos , Ratas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectrometría de Fluorescencia , Espectrofotometría , Espectrofotometría Ultravioleta
15.
Neurology ; 55(2): 309-11, 2000 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-10908915

RESUMEN

Several aspects of pyridoxine-dependent seizure (PDS) suggest a mutation affecting glutamate decarboxylase (GAD) as a possible cause. To examine the possibility of GAD linkage with PDS, the authors performed genotype analyses of three families using polymorphic markers near the GAD genes (GAD1 and GAD2). In each family, the affected siblings exhibited different genotypes for the GAD2 gene; in two families the GAD1 genotype was disparate. These findings suggest that a mutation of GAD is not directly involved in all cases of PDS.


Asunto(s)
Ligamiento Genético/genética , Genotipo , Glutamato Descarboxilasa/genética , Piridoxina/administración & dosificación , Espasmos Infantiles/genética , Deficiencia de Vitamina B 6/genética , Alelos , Niño , Preescolar , Análisis Mutacional de ADN , Femenino , Marcadores Genéticos/genética , Humanos , Lactante , Recién Nacido , Isoenzimas/genética , Masculino
16.
Neurochem Int ; 37(2-3): 111-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10812196

RESUMEN

It is widely recognized that the two major forms of GAD present in adult vertebrate brains are each composed of two major sequence domains that differ in size and degree of similarity. The amino-terminal domain is smaller and shows little sequence identity between the two forms. This domain is thought to mediate the subcellular targeting of the two GADs. Substantial parts of the amino-terminal domain appear to be exposed and flexible, as shown by proteolysis experiments and the locations of posttranslational modifications. The carboxyl-terminal sequence domain contains the catalytic site and shows substantial sequence similarity between the forms. The interaction of GAD with its cofactor, pyridoxal-5' phosphate (pyridoxal-P), plays a key role in the regulation of GAD activity. Although GAD(65) and GAD(67) interact differently with pyridoxal-P, their cofactor-binding sites contain the same set of nine putative cofactor-binding residues and have the same basic structural fold. Thus the cofactor-binding differences cannot be attributed to fundamental structural differences between the GADs but must result from subtle modifications of the basic cofactor-binding fold. The presence of another conserved motif suggests that the carboxyl-terminal domain is composed of two functional domains: the cofactor-binding domain and a small domain that closes when the substrate binds. Finally, GAD is a dimeric enzyme and conserved features of GADs superfamily of pyridoxal-P proteins indicate the dimer-forming interactions are mediated mainly by the carboxyl-terminal domain.


Asunto(s)
Encéfalo/enzimología , Glutamato Descarboxilasa/fisiología , Animales , Cerebelo/enzimología , Electroforesis en Gel de Poliacrilamida , Glutamato Descarboxilasa/química , Glutamato Descarboxilasa/metabolismo , Hidrólisis , Immunoblotting , Isoenzimas/química , Isoenzimas/metabolismo , Isoenzimas/fisiología , Masculino , Espectrometría de Masas , Peso Molecular , Conformación Proteica , Procesamiento Proteico-Postraduccional , Ratas , Ratas Wistar , Proteínas Recombinantes/química , Tripsina
17.
J Immunol ; 164(2): 779-85, 2000 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10623823

RESUMEN

The injection of Schistosoma mansoni eggs into the footpads of mice results in a localized Th2 cytokine response and tissue eosinophilia. We examined whether treatment with CD40-activating Abs would block the development of Th2 cytokine responses and eosinophilic tissue pathology in this model. Seven days after C57BL/6 mice were injected with eggs and the FGK45 anti-CD40 Ab, Ag-specific synthesis of IL-4, IL-5, and IL-13 in lymph node culture was reduced (>10-fold) relative to control mice treated with eggs and rat IgG. In contrast, IFN-gamma and IL-12 were increased in both culture supernatants and in the serum. Similar changes in lymph node cytokine mRNA were observed in vivo, and tissue eosinophilia was reduced nearly 20-fold. Th2 cytokine responses in anti-CD40-treated IFN-gamma-/- and IL-12 p40-/- C57BL/6 mice were unaffected, although anti-CD40 induced high levels of systemic and local IFN-gamma production in both wild-type and IL-12 p40-/- mice. We conclude that CD40-activating treatments strongly reverse the immune phenotype generated in response to a classic, Th2-biasing stimulus and stimulate IFN-gamma through a novel IL-12-independent pathway. This model for Th1-deviating immune therapy may have relevance to the treatment of Th2-dependent diseases in general.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antígenos CD40/inmunología , Inmunosupresores/farmacología , Interferón gamma/fisiología , Óvulo/inmunología , Schistosoma mansoni/inmunología , Células Th2/inmunología , Células Th2/metabolismo , Animales , Anticuerpos Monoclonales/administración & dosificación , Citocinas/biosíntesis , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Eosinofilia/inmunología , Eosinofilia/parasitología , Eosinofilia/terapia , Femenino , Miembro Posterior , Inmunosupresores/administración & dosificación , Inyecciones Intradérmicas , Inyecciones Intraperitoneales , Interferón gamma/deficiencia , Interferón gamma/genética , Interleucina-12/deficiencia , Interleucina-12/genética , Interleucina-13/antagonistas & inhibidores , Interleucina-13/biosíntesis , Interleucina-4/antagonistas & inhibidores , Interleucina-4/biosíntesis , Interleucina-5/antagonistas & inhibidores , Interleucina-5/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Th2/parasitología
19.
Neurochem Int ; 35(1): 73-80, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10403432

RESUMEN

The levels of the two isoforms of glutamate decarboxylase (GAD) were measured in 12 regions of adult rat brain and three regions of mouse brain by sodium dodecylsulfate-polyacrylamide gel electrophoresis and immunoblotting with an antiserum that recognizes the identical C-terminal sequence in both isoforms from both species. In rat brain the amount of smaller isoform, GAD65, was greater than that of the larger isoform, GAD67, in all twelve regions. GAD65 ranged from 77-89% of total GAD in frontal cortex, hippocampus, hypothalamus, midbrain, olfactory bulb, periaqueductal gray matter, substantia nigra, striatum, thalamus and the ventral tegmental area. The proportion of GAD65 was lower in amygdala and cerebellum but still greater than half of the total. There was a strong correlation between total GAD protein and GAD activity. In the three mouse brain regions analysed (cerebellum, cerebral cortex and hippocampus) the proportion of GAD65 (35,47, and 51% of total GAD) was significantly lower than in the corresponding rat-brain regions. The amount of GAD67 was greater than the amount of GAD65 in mouse cerebellum and was approximately equal to the amount of GAD65 in mouse cerebral cortex and hippocampus.


Asunto(s)
Encéfalo/enzimología , Glutamato Descarboxilasa/metabolismo , Secuencia de Aminoácidos , Animales , Glutamato Descarboxilasa/análisis , Immunoblotting , Isoenzimas/análisis , Isoenzimas/metabolismo , Ratones , Datos de Secuencia Molecular , Especificidad de Órganos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Ratas , Proteínas Recombinantes/análisis , Proteínas Recombinantes/inmunología , Especificidad de la Especie , Spodoptera , Transfección
20.
Arch Biochem Biophys ; 364(2): 195-202, 1999 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10190974

RESUMEN

The conformation of bovine serum albumin (BSA), a pyridoxal phosphate (pyridoxal-P) carrier, was investigated by using uv/visible spectrophotometry, fluorescence spectroscopy, circular dichroism, and differential scanning microcalorimetry. Upon interacting with pyridoxal-P, the uv/visible absorption spectrum of BSA exhibits peaks at 330 and 392 nm due to the formation of a Schiff base. Pyridoxal-P quenches the fluorescence emission intensity (excited at 295 or 280 nm) by 24% and enhances fluorescence steady-state polarization of BSA by 20%. These observations suggest a conformational change in BSA when it interacts with pyridoxal-P. However, this conformational change appears to be small since circular dichroism showed only a 2-4% decrease in the alpha-helical content of BSA and no change in the beta-sheet content, and differential scanning microcalorimetry yielded only a 10% change in the enthalpy of thermal unfolding of BSA. 2-Aminoethylisothiouronium bromide, an antioxidant, causes no effect on either uv/visible absorption spectrum or fluorescence emission intensity of BSA, suggesting that BSA lacks sensitive sulfhydryl groups. To help in understanding BSA as a carrier for pyridoxal-P, the results were compared with those for glutamate decarboxylase (GAD), a pyridoxal-P-dependent protein, which requires pyridoxal-P as the cofactor for activity. Although BSA and GAD exhibit comparable molecular weights (66430 versus 65300), numbers of amino acid residues (582 versus 585), and binding affinity (>10(6) M-1), distinct conformational alterations occur between the two proteins upon interacting with pyridoxal-P: a small conformational change for BSA versus a large conformational change for GAD. In contrast to the case of BSA, AET causes significant effects on both the uv/visible spectrum and fluorescence emission intensity of GAD, because GAD contains sensitive sulfhydryl groups. Factors such as disulfide bond and active site sequence were discussed to understand BAS as a carrier for pyridoxal-P and a pyridoxal-P-independent protein.


Asunto(s)
Glutamato Descarboxilasa/química , Fosfato de Piridoxal/química , Albúmina Sérica/química , Secuencia de Aminoácidos , Animales , Rastreo Diferencial de Calorimetría , Bovinos , Dicroismo Circular , Activación Enzimática , Polarización de Fluorescencia , Glutamato Descarboxilasa/metabolismo , Datos de Secuencia Molecular , Conformación Proteica , Fosfato de Piridoxal/metabolismo , Homología de Secuencia de Aminoácido , Albúmina Sérica/metabolismo , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
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