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This first-in-human study of AGN1 LOEP demonstrated that this minimally-invasive treatment durably increased aBMD in femurs of osteoporotic postmenopausal women. AGN1 resorption was coupled with new bone formation by 12 weeks and that new bone was maintained for at least 5-7 years resulting in substantially increased FEA-estimated femoral strength. INTRODUCTION: This first-in-human study evaluated feasibility, safety, and in vivo response to treating proximal femurs of postmenopausal osteoporotic women with a minimally-invasive local osteo-enhancement procedure (LOEP) to inject a resorbable triphasic osteoconductive implant material (AGN1). METHODS: This prospective cohort study enrolled 12 postmenopausal osteoporotic (femoral neck T-score ≤ - 2.5) women aged 56 to 89 years. AGN1 LOEP was performed on left femurs; right femurs were untreated controls. Subjects were followed-up for 5-7 years. Outcomes included adverse events, proximal femur areal bone mineral density (aBMD), AGN1 resorption, and replacement with bone by X-ray and CT, and finite element analysis (FEA) estimated hip strength. RESULTS: Baseline treated and control femoral neck aBMD was equivalent. Treated femoral neck aBMD increased by 68 ± 22%, 59 ± 24%, and 58 ± 27% over control at 12 and 24 weeks and 5-7 years, respectively (p < 0.001, all time points). Using conservative assumptions, FEA-estimated femoral strength increased by 41%, 37%, and 22% at 12 and 24 weeks and 5-7 years, respectively (p < 0.01, all time points). Qualitative analysis of X-ray and CT scans demonstrated that AGN1 resorption and replacement with bone was nearly complete by 24 weeks. By 5-7 years, AGN1 appeared to be fully resorbed and replaced with bone integrated with surrounding trabecular and cortical bone. No procedure- or device-related serious adverse events (SAEs) occurred. CONCLUSIONS: Treating femurs of postmenopausal osteoporotic women with AGN1 LOEP results in a rapid, durable increase in aBMD and femoral strength. These results support the use and further clinical study of this approach in osteoporotic patients at high risk of hip fracture.
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Densidad Ósea , Fracturas de Cadera , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Femenino , Fémur/diagnóstico por imagen , Fémur/cirugía , Cuello Femoral/cirugía , Humanos , Persona de Mediana Edad , Posmenopausia , Estudios ProspectivosRESUMEN
BACKGROUND: Genetic epilepsy with febrile seizures plus (GEFS+) is a familial epilepsy syndrome with extremely variable expressivity. Mutations in 5 genes that raise susceptibility to GEFS+ have been discovered, but they account for only a small proportion of families. METHODS: We identified a 4-generation family containing 15 affected individuals with a range of phenotypes in the GEFS+ spectrum, including febrile seizures, febrile seizures plus, epilepsy, and severe epilepsy with developmental delay. We performed a genome-wide linkage analysis using microsatellite markers and then saturated the potential linkage region identified by this screen with more markers. We evaluated the evidence for linkage using both model-based and model-free (posterior probability of linkage [PPL]) analyses. We sequenced 16 candidate genes and screened for copy number abnormalities in the minimal genetic region. RESULTS: All 15 affected subjects and 1 obligate carrier shared a haplotype of markers at chromosome 6q16.3-22.31, an 18.1-megabase region flanked by markers D6S962 and D6S287. The maximum multipoint lod score in this region was 4.68. PPL analysis indicated an 89% probability of linkage. Sequencing of 16 candidate genes did not reveal a causative mutation. No deletions or duplications were identified. CONCLUSIONS: We report a novel susceptibility locus for genetic epilepsy with febrile seizures plus at 6q16.3-22.31, in which there are no known genes associated with ion channels or neurotransmitter receptors. The identification of the responsible gene in this region is likely to lead to the discovery of novel mechanisms of febrile seizures and epilepsy.
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Cromosomas Humanos Par 6/genética , Discapacidades del Desarrollo/genética , Epilepsia/genética , Convulsiones Febriles/genética , Adolescente , Adulto , Niño , Preescolar , Familia , Femenino , Dosificación de Gen , Ligamiento Genético , Predisposición Genética a la Enfermedad , Humanos , Lactante , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Linaje , Síndrome , Adulto JovenRESUMEN
OBJECTIVE: To define the clinical, radiologic, and genetic features of periventricular heterotopia (PH) with Ehlers-Danlos syndrome (EDS). METHODS: Exonic sequencing and single stranded conformational polymorphism (SSCP) analysis was performed on affected individuals. Linkage analysis using microsatellite markers on the X-chromosome was performed on a single pedigree. Western blotting evaluated for loss of filamin A (FLNA) protein and Southern blotting assessed for any potential chromosome rearrangement in this region. RESULTS: The authors report two familial cases and nine additional sporadic cases of the EDS-variant form of PH, which is characterized by nodular brain heterotopia, joint hypermobility, and development of aortic dilatation in early adulthood. MRI typically demonstrated bilateral nodular PH, indistinguishable from PH due to FLNA mutations. Exonic sequencing or SSCP analyses of FLNA revealed a 2762 delG single base pair deletion in one affected female. Another affected female harbored a C116 single point mutation, resulting in an A39G change. A third affected female had a 4147 delG single base pair deletion. One pedigree with no detectable exonic mutation demonstrated positive linkage to the FLNA locus Xq28, an affected individual in this family also had no detectable FLNA protein, but no chromosomal rearrangement was detected. CONCLUSION: These results suggest that the Ehlers-Danlos variant of periventricular heterotopia (PH), in part, represents an overlapping syndrome with X-linked dominant PH due to filamin A mutations.
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Encéfalo/anomalías , Proteínas Contráctiles/deficiencia , Síndrome de Ehlers-Danlos/genética , Proteínas de Microfilamentos/deficiencia , Mutación Puntual , Eliminación de Secuencia , Adolescente , Adulto , Sustitución de Aminoácidos , Niño , Cromosomas Humanos X/genética , Proteínas Contráctiles/genética , Proteínas Contráctiles/fisiología , Análisis Mutacional de ADN , Síndrome de Ehlers-Danlos/patología , Epilepsia/etiología , Exones/genética , Femenino , Filaminas , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/fisiología , Repeticiones de Microsatélite , Persona de Mediana Edad , Mutación Missense , Linaje , Fenotipo , Polimorfismo Conformacional Retorcido-SimpleRESUMEN
BACKGROUND: Familial periventricular heterotopia (PH) represents a disorder of neuronal migration resulting in multiple gray matter nodules along the lateral ventricular walls. Prior studies have shown that mutations in the filamin A (FLNA) gene can cause PH through an X-linked dominant inheritance pattern. OBJECTIVE: To classify cortical malformation syndromes associated with PH. METHODS: Analyses using microsatellite markers directed toward genomic regions of FLNA and to a highly homologous autosomal gene, FLNB, were performed on two pedigrees to evaluate for linkage with either filamin gene. RESULTS: Two consanguineous pedigrees with PH that suggest an autosomal recessive inheritance pattern are reported. MRI of the brain revealed periventricular nodules of cerebral gray matter intensity, typical for PH. Seizures or developmental delay appeared to be a common presenting feature. Microsatellite analysis suggested no linkage to FLNA or FLNB. CONCLUSIONS: Autosomal recessive PH is another syndromic migrational disorder, distinct from X-linked dominant PH. Further classification of these different syndromes will provide an approach for genetic evaluation.
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Encefalopatías/genética , Ventrículos Cerebrales/anomalías , Coristoma/genética , Adulto , Anciano , Encefalopatías/complicaciones , Encefalopatías/diagnóstico , Movimiento Celular/genética , Preescolar , Coristoma/complicaciones , Coristoma/diagnóstico , Cromosomas Humanos Par 3/genética , Cromosomas Humanos X/genética , Consanguinidad , Proteínas Contráctiles/genética , Discapacidades del Desarrollo/genética , Electroencefalografía , Femenino , Filaminas , Genes Recesivos , Ligamiento Genético , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Proteínas de Microfilamentos/genética , Repeticiones de Microsatélite , Persona de Mediana Edad , Linaje , Convulsiones/genética , Turquía/etnología , Yemen/etnologíaRESUMEN
A new method using hydrostatic suctions (less than 0.02 MPa) was used to measure whole-root conductivity (K(r)) in saplings of two angiosperm pioneer trees (Eucalyptus regnans and Toona australis) and two rainforest conifers (Dacrycarpus dacrydioides and Nageia fleurii). The resultant K(r) was combined with measurements of stem and leaf hydraulic conductivity to calculate whole-plant conductivity and to predict leaf water potential (Psi(l)) during transpiration. At normal soil temperatures there was good agreement between measured and predicted Psi(l) during transpiration in all species. Changes in the soil-to-leaf water potential gradient were produced by root chilling, and in three of the four species, changes in Psi(l) corresponded to those expected by the effect of increased water viscosity on K(r). In one species, however, root chilling produced severe plant wilting and a decline in Psi(l) significantly below the predicted value. In this species Psi(l) decreased to a value close to, or below, the Psi(l) at 50% xylem cavitation. It is concluded that decreased whole-plant conductivity in T. australis resulted from a decrease in xylem conductivity due to stress-induced cavitation.
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Estructuras de las Plantas/fisiología , Árboles/fisiología , Agua/fisiología , Algoritmos , Transporte Biológico , Raíces de Plantas/fisiologíaRESUMEN
PURPOSE: Proton magnetic resonance spectroscopic imaging ((1)H-MRSI) is a noninvasive technique for spatial characterization of biochemical markers in tissues. We measured the relative tumor concentrations of these biochemical markers in children with recurrent brain tumors and evaluated their potential prognostic significance. PATIENTS AND METHODS: (1)H-MRSI was performed on 27 children with recurrent primary brain tumors referred to our institution for investigational drug trials. Diagnoses included high-grade glioma (n = 10), brainstem glioma (n = 7), medulloblastoma/peripheral neuroectodermal tumor (n = 6), ependymoma (n = 3), and pineal germinoma (n = 1). (1)H-MRSI was performed on 1. 5-T magnetic resonance imagers before treatment. The concentrations of choline (Cho) and N-acetyl-aspartate (NAA) in the tumor and normal brain were quantified using a multislice multivoxel method, and the maximum Cho:NAA ratio was determined for each patient's tumor. RESULTS: The maximum Cho:NAA ratio ranged from 1.1 to 13.2 (median, 4.5); the Cho:NAA ratio in areas of normal-appearing brain tissue was less than 1.0. The maximum Cho:NAA ratio for each histologic subtype varied considerably; approximately equal numbers of patients within each tumor type had maximum Cho:NAA ratios above and below the median. Patients with a maximum Cho:NAA ratio greater than 4.5 had a median survival of 22 weeks, and all 13 patients died by 63 weeks. Patients with a Cho:NAA ratio less than or equal to 4.5 had a projected survival of more than 50% at 63 weeks. The difference was statistically significant (P =.0067, log-rank test). CONCLUSION: The maximum tumor Cho:NAA ratio seems to be predictive of outcome in children with recurrent primary brain tumors and should be evaluated as a prognostic indicator in newly diagnosed childhood brain tumors.
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Neoplasias Encefálicas/diagnóstico , Espectroscopía de Resonancia Magnética/métodos , Adolescente , Adulto , Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Niño , Preescolar , Humanos , Recurrencia Local de Neoplasia , Proyectos Piloto , Pronóstico , ProtonesRESUMEN
Functional porcine islets, free of known pathogens, can serve as a source of insulin producing cells for the treatment of experimentally induced insulin dependent Diabetes Mellitus. Porcine islets can be conformally coated (microencapsulated) with a covalently linked, stable permselective membrane while maintaining islet viability and function. The PEG conformal coating is immunoprotective in a discordant xenograft animal model (porcine islets to rat).
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Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos/métodos , Páncreas Artificial , Polietilenglicoles , Inmunología del Trasplante , Animales , Materiales Biocompatibles , Cápsulas , Trasplante de Islotes Pancreáticos/inmunología , Membranas Artificiales , Fotoquímica , Ratas , PorcinosRESUMEN
PURPOSE: To evaluate the use of orally administered water as a negative contrast agent and intravenously administered glucagon in helical computed tomography (CT) of the upper abdomen. MATERIALS AND METHODS: Ninety-eight adult patients underwent 102 helical CT examinations. Patients received 700 mL of water orally 30 minutes before and another 350 mL of water orally with 1 mg of glucagon intravenously just before CT. The amount of water actually ingested was recorded. Luminal distention at five sites was graded on a three-point scale; depiction of six normal anatomic structures was evaluated. RESULTS: Luminal distention improved with the amount of water ingested in four of the five sites (P < .03 in three sites). Depiction of all six normal anatomic structures improved with increasing luminal distention (P < .001). The normal duodenal papilla was seen in 42% (83 of 198) of the examinations. Of 87 patients who had previously undergone CT with positive oral contrast agents, 89% (n = 77) preferred the water, 11% (n = 10) had no preference, and none preferred the positive agent (P < .001). Upper gastrointestinal tract abnormalities were easily recognized and depicted. CONCLUSION: Water is an efficacious negative contrast agent for evaluation of the upper gastrointestinal tract during helical CT.
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Medios de Contraste/administración & dosificación , Sistema Digestivo/diagnóstico por imagen , Radiografía Abdominal , Tomografía Computarizada por Rayos X , Agua , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Sistema Digestivo/efectos de los fármacos , Femenino , Glucagón/administración & dosificación , Glucagón/farmacología , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Agua/administración & dosificaciónRESUMEN
One hundred seventy-six of 209 consecutive new patients were examined over a 6-week period for the presence or absence of equinus deformity in the course of their workup for their primary complaint. Of the patients examined, 96.5% exhibited restricted ankle dorsiflexion requiring compensation during gait. Foot complaints were categorized into medial, lateral, and rearfoot problems. The high incidence of equinus reflects "acquired deformity" related to factors of lifestyle that leave the posterior muscles at a physiologic disadvantage toward maintaining flexibility. There is a significant relation between compensation for ankle equinus and podiatric pathology. More attention should be directed at the evaluation of ankle range of motion during examination of common foot problems. Gastrosoleal stretching is an important treatment modality that can lead to a higher success rate of conservative treatment. It can decrease the need for foot surgery, and significantly reduce the number of failed or serial surgical procedures.
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Articulación del Tobillo , Enfermedades del Pie , Marcha , Dolor , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Niño , Humanos , Persona de Mediana EdadAsunto(s)
Islotes Pancreáticos/citología , Soluciones Preservantes de Órganos , Adenosina , Alopurinol , Aminoquinolinas , Animales , Recuento de Células , Separación Celular , Colorantes Fluorescentes , Glutatión , Insulina , Microscopía Fluorescente , Páncreas/citología , Rafinosa , Porcinos , Conservación de Tejido , Compuestos de TosiloRESUMEN
An x-ray surface forces apparatus for simultaneously measuring forces and structures of confined complex fluids under static and flow conditions is described. This apparatus, combined with an intense synchrotron x-ray source, allows investigation of molecular orientations within a thin liquid crystal film confined between two shearing mica surfaces 3900 angstroms apart. The layer-forming smectic liquid crystal 8CB (4-cyano-4'-octylbiphenyl) adopted a series of distinct planar layer orientations, including the bulk flow-forbidden b orientation.
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Cámaras de Difusión de Cultivos , Reacción a Cuerpo Extraño/inmunología , Supervivencia de Injerto/inmunología , Membranas Artificiales , Neovascularización Patológica/inmunología , Politetrafluoroetileno , Animales , Cápsulas , Reacción a Cuerpo Extraño/patología , Neovascularización Patológica/patología , Porosidad , Ratas , Ratas Desnudas , Propiedades de SuperficieRESUMEN
Nothofagus holds a premier position in the study of Southern Hemisphere plant evolution and biogeography, and many have attempted to reconstruct its history. A recent surge of research on both living and fossil species has added valuable data to the debate, but has also introduced complications, including the now less certain familial relationships of the genus. The vast quantity of fossil evidence provides an extremely firm base for reconstruction of the past distribution of Nothofagus, and allows informed speculation on the time and places of origin and major speciation events.
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Recombinant tissue consisting of adult ductal epithelium isolated from pancreas and fetal mesenchyme was transplanted subcutaneously in the inguinal region of nude mice or epididymal fat pads of rats with a tissue chamber device for short-term (8-day) or long-term (6- to 12-wk) duration. We found that recombinant tissue underwent morphogenesis and cytodifferentiation, thereby forming islets that contained cells immunocytochemically positive for insulin and glucagon. Islet cytodifferentiation occurred in approximately 20% of the recombinants. In recombinants that developed into islets, the tissue was always in close association with an extracellular matrix, nerves, and blood vessels. Controls consisting of mesenchyme alone or duct epithelium alone showed no evidence of morphogenesis of cytodifferentiation. Pancreatic rudiments were also implanted to serve as positive controls. This is the first demonstration of islet cytodifferentiation from adult duct epithelium.
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Trasplante de Tejido Fetal/fisiología , Islotes Pancreáticos/citología , Trasplante de Páncreas/fisiología , Animales , Diferenciación Celular , Epitelio/trasplante , Epitelio/ultraestructura , Glucagón/análisis , Inmunohistoquímica , Insulina/análisis , Islotes Pancreáticos/ultraestructura , Masculino , Ratones , Ratones Desnudos , Microscopía Electrónica , Morfogénesis , Ratas , Ratas Endogámicas Lew , Ratas Endogámicas , Trasplante HeterólogoRESUMEN
The CD34 antigen is expressed by 1% to 4% of human and baboon marrow cells, including virtually all hematopoietic progenitors detectable by in vitro assays. Previous work from our laboratory has shown that CD34+ marrow cells can engraft lethally irradiated baboons. Because the CD34 antigen has not been detected on most solid tumors, positive selection of CD34+ cells may be used to provide marrow cells capable of engraftment, but depleted of tumor cells. In seven patients with stage IV breast cancer and two patients with stage IV neuroblastoma, 2.5 to 17.5 x 10(9) marrow cells were separated by immunoadsorption with the anti-CD34 antibody 12-8 and 50 to 260 x 10(6) positively selected cells were recovered that were 64 +/- 16% (range 35% to 92%) CD34+. The patients received 1.0 to 5.2 x 10(6) CD34-enriched cells/kg after marrow ablative therapy. Six patients engrafted, achieving granulocyte counts of greater than 500/mm3 at 34 +/- 10 (range 21 to 47) days and platelets counts of greater than 20,000/mm3 at 46 +/- 14 (range 28 to 66) days posttransplant. Five of these patients showed durable engraftment until the time of death 82 to 386 days posttransplant. One patient failed to sustain engraftment associated with metastatic marrow disease. Three patients died at days 14, 14, and 17 posttransplant, two of whom had evidence of early engraftment. These studies suggest that CD34+ marrow cells are capable of reconstituting hematopoiesis in humans.
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Antígenos CD/análisis , Antígenos de Diferenciación/análisis , Trasplante de Médula Ósea , Neoplasias de la Mama/cirugía , Trasplante de Células Madre Hematopoyéticas , Neuroblastoma/cirugía , Antígenos CD34 , Trasplante de Médula Ósea/inmunología , Neoplasias de la Mama/inmunología , Células Cultivadas , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Neuroblastoma/inmunología , Irradiación Corporal TotalRESUMEN
Two cases are reported in which patients presented with complaints of foot pain, and a clinical suspicion of radiculopathy was supported by current perception threshold testing. Chiropractic manipulation of the lumbar spine resulted in alleviation of the lower extremity symptoms. Current perception threshold testing is a valuable neurologic testing modality that is noninvasive, nonaversive, and highly reliable for evaluation of sensory nerves where neuropathy is suspected. This technology has been described for evaluation of diabetic neuropathy, uremic screening, and alcohol and chemical toxicity. Additionally, current perception threshold is useful for evaluation of other neuropathies, such as carpal tunnel syndrome and other entrapment neuropathies. The authors encourage further investigation of this modality in the diagnosis and evaluation of peripheral neuropathy and unexplained foot pain secondary to spinal nerve impingement.
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Enfermedades del Pie/diagnóstico , Dimensión del Dolor/métodos , Dolor/diagnóstico , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Adulto , Estimulación Eléctrica , Enfermedades del Pie/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Enfermedades del Sistema Nervioso Periférico/complicaciones , Umbral SensorialRESUMEN
A preliminary report of a new bunion procedure is described. This new procedure provides a relative reduction of the intermetatarsal angle and corrects the proximal articular set angle, yet incorporates the principles of compressive rigid internal fixation. The procedure is best summarized as a combination of the Kalish modification of the Austin bunionectomy and the Green-Laird modification of the Reverdin bunionectomy.
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Hallux Valgus/cirugía , Osteotomía/métodos , Adolescente , Adulto , Anciano , Hilos Ortopédicos , Femenino , Estudios de Seguimiento , Hallux Valgus/diagnóstico por imagen , Hallux Valgus/patología , Humanos , Persona de Mediana Edad , Osteotomía/instrumentación , RadiografíaRESUMEN
The ability to obtain large numbers of purified hematopoietic progenitors (HPC) will facilitate the understanding of elements that influence the growth and differentiation of bone marrow. Furthermore, HPC isolation will have direct application to autologous marrow transplantation (AMT) for malignancies as well as facilitate the transfer of genes in marrow cells for the correction of genetic disorders. The transplantation of HPC will help delineate the cells or factors responsible for graft rejection and graft-versus-host-disease. Or several techniques that have been utilized for the separation of HPC, only the avidin-biotin immunoadsorption (ABIA) method has been shown capable of separating the number of cells required for large animals and man. The application of this technique to AMT in man requires the identification of an antigen found predominantly on HPC in peripheral blood or marrow but not on malignant cells that could potentially contaminate bone marrow. Studies have demonstrated that the CD34 antigen is expressed by the majority of human marrow HPC measured in long-term marrow culture and is expressed on cells capable of autologous engraftment in lethally irradiated baboons. Although the CD34 antigen is not detectable by FACS analysis on peripheral blood cells, ABIA can enrich for such cells. The CD34 antigen is not detected on cells from patients with breast cancer or neuroblastoma thus allowing clinical studies to proceed. Preliminary results suggest that CD34(+)-enriched cells are depleted of tumor cells and are capable of autologous reconstitution in man.
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Antígenos CD/análisis , Trasplante de Médula Ósea/inmunología , Células Madre Hematopoyéticas/inmunología , Células Sanguíneas/inmunología , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/secundario , Femenino , Humanos , Linfoma/inmunología , Masculino , Neuroblastoma/inmunologíaRESUMEN
With a glucose-responsive beta-cell line (HIT cells), we tested the hypothesis that the cytosolic free-Ca2+ level ([Ca2+]i) is an intracellular signal through which a rise in cyclic AMP (cAMP) levels is transmitted to potentiate glucose-stimulated insulin secretion. In these cells, glucose stimulates the acute release of insulin without increasing [Ca2+]i or altering cAMP content. Either forskolin or 3-isobutylmethylxanthine (IBMX) potentiated glucose-stimulated insulin secretion and increased cAMP levels. At either a submaximal glucose concentration or maximally stimulatory glucose concentration, both IBMX and forskolin triggered a rapid rise in [Ca2+]i (1.9- and 1.5-fold increase over basal levels, respectively). Similarly, glucagon stimulated a 1.3-fold increase in [Ca2+]i over basal levels. The effect on [Ca2+]i required glucose and was secondary to Ca2+ influx through voltage-dependent Ca2+ channels because it was blocked by either chelation of extracellular Ca2+ with EGTA or by the Ca2+-channel blockers verapamil and nimodipine. Verapamil also inhibited IBMX potentiation of glucose-stimulated insulin secretion and the IBMX-induced rise in [Ca2+]i in a dose-dependent manner with IC50s of 2 x 10(-5) and 4 x 10(-6) M, respectively. We conclude that in the beta-cell, a rise in cAMP levels increases Ca2+ influx through voltage-dependent Ca2+ channels and that this represents a mechanism by which cAMP potentiates glucose-stimulated insulin secretion in beta-cells.
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Canales de Calcio/metabolismo , Calcio/metabolismo , AMP Cíclico/metabolismo , Islotes Pancreáticos/citología , Sistemas de Mensajero Secundario , 1-Metil-3-Isobutilxantina/farmacología , Animales , Benzofuranos/farmacología , Canales de Calcio/fisiología , Línea Celular , Células Cultivadas , Colforsina/farmacología , AMP Cíclico/fisiología , Electrofisiología , Fura-2 , Glucagón/farmacología , Glucosa/farmacología , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/fisiología , Verapamilo/farmacologíaRESUMEN
The kinetics of marrow engraftment was retrospectively analysed in 55 patients with malignant lymphoma (ML) and 31 patients with acute lymphoblastic leukemia (ALL) after marrow-ablative therapy followed by autologous bone marrow transplantation. Thirty-eight percent of patients with ML, most of whom were transplanted in relapse and 13% of patients with ALL, mostly transplanted in remission, showed failed or delayed engraftment. Analysis of the total patient group showed that failure to recover platelet counts was significantly correlated with detection of disease in the marrow early after transplantation (p less than 0.001). Platelet recovery was also correlated with survival (p = 0.0001), disease-free survival (p = 0.0001), and the probability of relapse (p = 0.02). In those patients achieving engraftment, multivariate regression analysis failed to reveal any single in vitro test of marrow nucleated cell or progenitor cell numbers that significantly influenced time to achieve recovery of either granulocyte or platelet counts.