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1.
J Cell Biol ; 120(1): 205-15, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8416988

RESUMEN

We have examined the expression of brain-specific tropomyosins during neuronal differentiation. Both TmBr-1 and TmBr-3 were shown to be neuron specific. TmBr-1 and TmBr-3 mRNA levels increased during the most active phase of neurite outgrowth in the developing rat cerebellum. In PC12 cells stimulated by nerve growth factor (NGF) to differentiate to the neuronal phenotype, TmBr-1 and TmBr-3 levels increased with an increasing degree of morphological differentiation. Induction of TmBr-1 and TmBr-3 expression only occurred under conditions where PC12 cells were permitted to extend neurites. NGF was unable to maintain levels of TmBr-1 and TmBr-3 with the loss of neuronal phenotype by resuspension of differentiated PC12 cells. The unique cellular expression and regulation in vivo and in vitro of TmBr-1 and TmBr-3 strongly suggests a critical role of these tropomyosins in neuronal microfilament function. The findings reveal that the induction and maintenance of the neuronal tropomyosins is dependent on morphological differentiation and the maintenance of the neuronal phenotype.


Asunto(s)
Factores de Crecimiento Nervioso/farmacología , Neuronas/fisiología , Tropomiosina/genética , Citoesqueleto de Actina/fisiología , Animales , Secuencia de Bases , Diferenciación Celular , Cerebelo/embriología , Cerebelo/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos/química , Células PC12 , Reacción en Cadena de la Polimerasa , Empalme del ARN , ARN Mensajero/genética , Ratas
2.
Science ; 276(5317): 1382-6, 1997 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-9161999

RESUMEN

Planetary nebulae are one of the few classes of celestial objects that are active in every part of the electromagnetic spectrum. These fluorescing and often dusty expanding gaseous envelopes were recently found to be quite complex in their dynamics and morphology, but refined theoretical models can account for these discoveries. Great progress was also made in understanding the mechanisms that shape the nebulae and the spectra of their central stars. In addition, applications for planetary nebulae have been worked out; for example, they have been used as standard candles for long-range distances and as tracers of the enigmatic dark matter.


Asunto(s)
Astronomía , Evolución Planetaria , Fenómenos Astronómicos , Análisis Espectral
3.
Eur J Paediatr Neurol ; 23(4): 581-588, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31155454

RESUMEN

AIM: To assess the improvement in gross motor function following three blocks of a three-week, intensive robot-enhanced treadmill therapy (ROBERT-Program). METHOD: retrospective chart review in a before-after interventional trial in children with cerebral palsy attending a university hospital outpatient rehabilitation centre. Patients received three blocks of a three-week, 12 sessions ROBERT-Program over a mean period of 24 months. Outcome measures were block specific and cumulative improvement in GMFM 66, D and E. Longterm GMFM 66 improvements were compared to the individuals' expected increment as derived from previously published GMFM-66 percentiles. 95% confidence intervals (CI) and paired t-test were calculated. RESULTS: 20 children (8 GMFCS Level II; 12 GMFCS Level III, mean age 5.9 years (CI: [5.0; 6.7])) were treated. For each block a significant increase in motor performance in similar size could be observed without deterioration between blocks. The cumulative improvement during 21 months observation period was: 6.5 (CI: [4.8; 8.2]) in GMFM 66, which represents a clinically meaningful effect size of 3.6 (CI: [1.4; 5.8]) above the expected improvement. INTERPRETATION: Progressive clinically meaningful improvement in motor performance for three blocks of ROBERT-Program was observed. Cumulative GMFM 66 improvements exceeded the individuals' age-specific expected course.


Asunto(s)
Parálisis Cerebral/rehabilitación , Terapia por Ejercicio/instrumentación , Terapia por Ejercicio/métodos , Dispositivo Exoesqueleto , Destreza Motora , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Retrospectivos
4.
Eur Psychiatry ; 48: 20-26, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29331595

RESUMEN

BACKGROUND: The 22q11.2 deletion syndrome (22q11DS) is the most common genetic syndrome associated with schizophrenia. The goal of this study was to evaluate longitudinally the interaction between neurocognitive functioning, the presence of subthreshold psychotic symptoms (SPS) and conversion to psychosis in individuals with 22q11DS. In addition, we attempted to identify the specific neurocognitive domains that predict the longitudinal evolution of positive and negative SPS, as well as the effect of psychiatric medications on 22q11DS psychiatric and cognitive developmental trajectories. METHODS: Forty-four participants with 22q11DS, 19 with Williams syndrome (WS) and 30 typically developing (TD) controls, age range 12-35years, were assessed at two time points (15.2±2.1months apart). Evaluation included the Structured Interview for Prodromal Symptoms (SIPS), structured psychiatric evaluation and the Penn Computerized Neurocognitive Battery (CNB). RESULTS: 22q11DS individuals with SPS had a yearly conversion rate to psychotic disorders of 8.8%, compared to none in both WS and TD controls. Baseline levels of negative SPS were associated with global neurocognitive performance (GNP), executive function and social cognition deficits, in individuals with 22q11DS, but not in WS. Deficits in GNP predicted negative SPS in 22q11DS and the emergence or persistence of negative SPS. 22q11DS individuals treated with psychiatric medications showed significant improvement in GNP score between baseline and follow-up assessments, an improvement that was not seen in untreated 22q11DS. CONCLUSIONS: Our results highlight the time-dependent interplay among positive and negative SPS symptoms, neurocognition and pharmacotherapy in the prediction of the evolution of psychosis in 22q11DS.


Asunto(s)
Cognición/fisiología , Síndrome de DiGeorge/complicaciones , Trastornos Psicóticos/complicaciones , Esquizofrenia/complicaciones , Síndrome de Williams/complicaciones , Adolescente , Adulto , Antipsicóticos/uso terapéutico , Niño , Función Ejecutiva , Femenino , Humanos , Estudios Longitudinales , Masculino , Síntomas Prodrómicos , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Conducta Social , Adulto Joven
5.
Mol Biochem Parasitol ; 222: 1-5, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29655799

RESUMEN

Leishmania are obligatory intracellular parasites that cycle between the sand fly midgut (extracellular promastigotes) and mammalian macrophage phagolysosomes (intracellular amastigotes). They have developed mechanisms of adaptation to the distinct environments of host and vector that favor utilization of both proline and alanine. LdAAP24 is the L. donovani proline-alanine transporter. It is a member of Leishmania system A that translocates neutral amino acids. Since system A is promastigote-specific, we aimed to assess whether LdAAP24 is also expressed exclusively in promastigotes. Herein, we established that upon exposing L. donovani promastigotes to amastigote differentiation signal (pH 5.5 and 37 °C), parasites rapidly and completely degrade LdAAP24 protein in both axenic and in spleen-derived amastigotes. In contrast, LdAAP24 mRNA remained unchanged throughout differentiation. Addition of either MG132 or Bafilomycin A1 partially inhibited LdAAP24 protein degradation, indicating a role for both lysosome- and proteasome-mediated degradation. This work provides the first evidence for post-translational regulation of stage-specific expression of LdAAP24.


Asunto(s)
Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Leishmania donovani/metabolismo , Leishmaniasis Visceral/parasitología , Proteínas Protozoarias/metabolismo , Alanina/metabolismo , Sistemas de Transporte de Aminoácidos Neutros/genética , Animales , Humanos , Insectos Vectores/parasitología , Leishmania donovani/genética , Leishmania donovani/crecimiento & desarrollo , Lisosomas/metabolismo , Phlebotomus/parasitología , Prolina/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Proteínas Protozoarias/genética , Especificidad de la Especie
6.
Ground Water ; 45(5): 616-26, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17760587

RESUMEN

Steep hydraulic gradients are found in association with steep monoclinal flexures. However, the physics of the reduction of the hydraulic conductivity, which is responsible for the steep gradients, has seldom been studied. We present results of hydrological and mechanical modeling aiming to study the effect of such steep hydraulic gradients demonstrated in the Judea Group Aquifer system, Israel. The hydrological configuration of steep dips and anisotropy between flows parallel and perpendicular to the bedding planes was simulated using the FEFLOW code. It exhibited a situation whereby part of the flow is oblique to the bedding planes and therefore some steepening of the hydraulic gradients occurred due to actual conductivity reduction. However, this reduction is not enough to account for the steeper gradients observed. The effect of a deep-seated reverse fault under the monocline on the permeability distribution within the structure was examined by numerical mechanical simulations. It exhibited a compressional stress distribution in the steep part of the monocline, which, due to shortening and closure of joints and voids, is presumably responsible for a significant pressure-induced permeability reduction. This process by itself in a layered structure, including interlayering of thin marl layers, could be responsible for the steep hydraulic gradients in the steep part of the monocline.


Asunto(s)
Modelos Teóricos , Movimientos del Agua , Abastecimiento de Agua , Simulación por Computador , Fenómenos Geológicos , Geología , Permeabilidad
7.
Hum Gene Ther ; 12(1): 77-86, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11177545

RESUMEN

Peripheral nervous system (PNS) sensory neurons are directly involved in the pathophysiology of numerous inherited and acquired neurological conditions. Therefore, efficient and stable gene delivery to these postmitotic cells has significant therapeutic potential. Among contemporary vector systems capable of neuronal transduction, only those based on herpes simplex virus have been extensively evaluated in PNS neurons. We therefore investigated the transduction performance of recombinant adeno-associated virus type 2 (AAV) and VSV-G-pseudotyped lentivirus vectors derived from human immunodeficiency virus (HIV-1) in newborn mouse and fetal human dorsal root ganglia (DRG) sensory neurons. In dissociated mouse DRG cultures both vectors achieved efficient transduction of sensory neurons at low multiplicities of infection (MOIs) and sustained transgene expression within a 28-day culture period. Interestingly, the lentivirus vector selectively transduced neurons in murine cultures, in contrast to human cultures, in which Schwann and fibroblast-like cells were also transduced. Recombinant AAV transduced all three cell types in both mouse and human cultures. After direct microinjection of murine DRG explants, maximal transduction efficiencies of 20 and 200 transducing units per neuronal transductant were achieved with AAV and lentivirus vectors, respectively. Most importantly, both vectors achieved efficient and sustained transduction of human sensory neurons in dissociated cultures, thereby directly demonstrating the exciting potential of these vectors for gene therapy applications in the PNS.


Asunto(s)
Dependovirus/genética , Ganglios Espinales/virología , Lentivirus/genética , Glicoproteínas de Membrana , Neuronas Aferentes/virología , Proteínas Recombinantes/genética , Transducción Genética , Animales , Células Cultivadas , Expresión Génica , Marcación de Gen/métodos , Técnicas de Transferencia de Gen , Vectores Genéticos , Proteínas Fluorescentes Verdes , Humanos , Técnicas para Inmunoenzimas , Recién Nacido , Proteínas Luminiscentes/metabolismo , Ratones , Microscopía Fluorescente , Proteínas Recombinantes/metabolismo , Proteínas del Envoltorio Viral/metabolismo
8.
J Mol Endocrinol ; 31(2): 241-53, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14519093

RESUMEN

Changes in the cell cytoskeleton occur in cell transformation and recent data suggest the involvement of ovarian hormones, which are implicated in cancer development and progression. In human breast and endometrial tumors, there is disrupted expression of progesterone receptor (PR) isoforms and predominance of one isoform, usually PRA. PRA predominance is an early event in carcinogenesis, and in cancers is associated with poor clinical features. Overexpression of PRA in vitro causes altered progestin regulation of cell morphology, suggesting that PRA overexpression may provoke deleterious changes in cell functioning. This study aimed to identify pathways of cytoskeleton regulation responsive to progestins and to determine whether these are perturbed when PRA is overexpressed to the levels seen in cancers. Progestin treatment of PR-positive breast cancer cells caused increased cell surface area whereas after induction of a stably integrated PRA construct, cells became rounded and the cell surface was decreased. The effect of PRA induction on cell rounding was reversed by the anti-progestin RU38486. Altered tropomyosin (Tm) isoforms were implicated in these morphological differences, as there was a PRA-mediated alteration in Tm5 isoform levels, and transfection of Tm5a mimicked progestin-mediated cell rounding in PRA-overexpressing cells. Ezrin was redistributed from the membrane to cytoplasmic locations in the presence of progestin, and discrete focal localization was evident in cells with PRA predominance. Progestin effects on the cytoskeleton in PRA-overexpressing cells provide evidence for novel endocrine regulation of aspects of actin microfilament composition, suggesting that changes in the cytoskeleton known to be associated with cancer development and progression may be regulated in part by altered PRA expression which develops early in carcinogenesis.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Progestinas/metabolismo , Receptores de Progesterona/metabolismo , Transducción de Señal/fisiología , Actinas/metabolismo , Animales , Proteínas del Citoesqueleto/metabolismo , Femenino , Adhesiones Focales/metabolismo , Neoplasias Mamarias Animales/metabolismo , Neoplasias Mamarias Animales/patología , Fosfoproteínas/metabolismo , Progestinas/farmacología , Ratas , Transducción de Señal/efectos de los fármacos , Transactivadores/metabolismo , beta Catenina
9.
Neuroscience ; 72(4): 889-900, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8735217

RESUMEN

The differentiation of neurons involves the establishment of distinct molecular compartments which regulate neuronal shape and function. This requires targeting of specific gene products to growth-associated regions of the neuron. We have investigated the temporal and spatial regulation of SCG10 gene expression during neuronal differentiation. There are two SCG10 messenger RNAs, 1 and 2 kg in length, which encode the same growth-associated protein. These messenger RNAs were found to be differentially regulated during the onset of neurite outgrowth in early rat cerebellum development. In PC12 cells, the two SCG10 messenger RNAs were shown to be differentially induced by nerve growth factor. Regulation of the 2 kb messenger RNA, but not the 1 kb messenger RNA, is dependent on the differentiation of PC12 cells, indicating that post-transcriptional regulation of SCG10 expression during neurite outgrowth. Spatial regulation of the 2 kb SCG10 messenger RNA distribution during brain development was examined by in situ hybridization. The 2 kb messenger RNA was found to be localized to the neuronal pole where outgrowth was occurring, within differentiating neurons in vivo. Intracellular localization of SCG10 messenger RNA was also observed in differentiating primary cultured neurons, with the 2 kb messenger RNA transported into growing neurites during the development of neuronal polarity. In neurons which had developed polarity, the 2 kb SCG10 messenger RNA was consistently found in the cell body and axon. This study demonstrates both temporal and spatial post-transcriptional regulation of SCG10 expression which is associated with neurite outgrowth. The directed transport and positional translation of SCG10 messenger RNA provide a potential mechanism for protein targeting and the creation of molecular compartments during neuronal differentiation.


Asunto(s)
Factores de Crecimiento Nervioso/genética , Neuronas/fisiología , Ganglio Cervical Superior/citología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Proteínas Portadoras , Diferenciación Celular/genética , Células Cultivadas/fisiología , Cerebelo/embriología , Cerebelo/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Hibridación in Situ , Proteínas de la Membrana , Proteínas de Microtúbulos , Datos de Secuencia Molecular , Sistema Nervioso/embriología , Fenómenos Fisiológicos del Sistema Nervioso , Neuritas/fisiología , Neuronas/citología , Neuronas/ultraestructura , Regiones Promotoras Genéticas/fisiología , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Análisis de Secuencia de ADN , Ganglio Cervical Superior/embriología , Ganglio Cervical Superior/fisiología
10.
J Mol Neurosci ; 1(2): 93-104, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2561876

RESUMEN

Soluble calmodulin-stimulated protein kinase II has been purified from 2-day and adult chicken forebrain. At both ages the holoenzyme eluted from a Superose-6B column with an apparent molecular weight of approximately 700,000 daltons and contained three subunits. The subunits were found to be the counterparts of the alpha, beta, and beta' subunits of the enzyme purified from adult rat brain in that they had one-dimensional phosphopeptide maps that were indistinguishable from those of the corresponding subunit in the rat enzyme and they migrated in SDS-polyacrylamide gels with the same apparent molecular weights. However, the doublet formed by the beta subunit was much more clearly resolved in the chicken enzyme and the beta' subunit, which was much more abundant in the adult chicken than in the adult rat, was also found to be a doublet. The ratio of the concentrations of the alpha and beta subunits changed during development. By autoradiography following autophosphorylation, the alpha:beta ratios of the 2-day and adult enzymes were 0.89 +/- 0.07 and 1.92 +/- 0.26, respectively; by silver staining the alpha:beta ratios were 0.95 +/- 0.11 and 1.85 +/- 0.17, respectively. The concentration of the beta' subunit was equal to that of the beta subunit at both ages. Autophosphorylation produced a decrease in the electrophoretic mobility of the alpha and beta subunits in SDS-polyacrylamide gels and a marked decrease in the calcium dependence of the substrate phosphorylation activity of the enzyme at both ages. The purified enzyme from chicken brain appeared to be more stable under standard in vitro assay conditions than the rat enzyme, and this was particularly so for the enzyme from 2-day forebrain.


Asunto(s)
Encéfalo/enzimología , Proteínas Quinasas/aislamiento & purificación , Envejecimiento , Animales , Encéfalo/crecimiento & desarrollo , Proteínas Quinasas Dependientes de Calcio-Calmodulina , Pollos , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Cinética , Sustancias Macromoleculares , Peso Molecular , Fosfopéptidos/aislamiento & purificación , Fosforilación , Proteínas Quinasas/metabolismo
11.
J Neurosci Methods ; 67(2): 163-75, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8872882

RESUMEN

Using a unique protocol, we have developed an avian neuron culture system in which a high yield of Purkinje neurons is obtained more readily than with pre-existing methods. Purkinje neurons were identified in vitro using the specific antibodies calbindin and cyclic GMP-kinase. Survival of Purkinje neurons was dependent on astrocyte contact and enhanced by astrocytic factors supplied to the medium by a monolayer of astrocytes grown on coated membranes suspended in the culture wells but not in contact with the neurons. The age of the cerebellum from which astrocytes were obtained was shown to affect the morphological development of the Purkinje neurons suggesting the developmentally-regulated expression of growth factors. However, in the presence of the astrocytes, Purkinje neurons could only progress to a limited stage of development based on morphological criteria. The addition to the culture of cerebellar granule neurons at a time of Purkinje neuron development that they would expect to encounter them in vivo resulted in a shift of Purkinje neurons to a mature phenotype. This maturation effect was increased in response to increasing levels of granule neurons, but was independent of the granule neuron ages used. This system offers significant advantages over other Purkinje neuron culture systems and will be useful for studying the extrinsic factors involved in Purkinje neuron development and histogenesis.


Asunto(s)
Aves/fisiología , Células de Purkinje/fisiología , Animales , Astrocitos/fisiología , Agregación Celular , Recuento de Células , Diferenciación Celular , Células Cultivadas , Corteza Cerebelosa/citología , Embrión de Pollo , Técnicas de Cocultivo , Inmunohistoquímica , Microscopía Confocal , Neuritas/fisiología , Fenotipo
12.
Brain Res ; 471(2): 249-57, 1988 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-2846125

RESUMEN

The net level of cyclic AMP-stimulated protein phosphorylation was investigated in cytosolic and membrane fractions from chicken forebrain between embryonic day 13 (E13) and 52 days post-hatching. Throughout this period the majority of the net level of cAMP-stimulated phosphorylation of endogenous proteins was in the cytosolic fractions. Between day -8 (E13) and adult, the net level of cAMP-stimulated phosphorylation of endogenous proteins in the cytosol (S3) and crude synaptic plasma membrane (P2-M) fractions fell by 3 and 4 fold, respectively, when expressed per mg protein and rose by 5 and 10 fold, respectively, when expressed per fraction. The changes in specific activity were completed by 6-15 days post-hatching. The occluded cytosol (P2-S) fraction showed little change in the net level of cAMP-stimulated phosphorylation of endogenous proteins per mg protein. Major changes in phosphoprotein patterns involving both decreases and increases in phosphorylation occurred in all fractions from day -8 (E13) to day 6 post-hatch; thereafter the phosphoprotein bands and their relative intensities were unchanged. Three bands (P90 in S3; P41 and P31 in P2-M) contained major cAMP-stimulated phosphoproteins in embryonic brain but were absent after hatching. When cAMP-stimulated phosphorylation activity was measured in S3 and P-2M using an exogenous peptide substrate (Kemptide) there was no change in kinase activity per mg protein between day -8 (E13) and 30 days post-hatch. This suggests that the decrease in the net level of cAMP stimulated phosphorylation of endogenous proteins was due to the decrease in levels of endogenous phosphoproteins rather than protein kinase activity.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Envejecimiento/metabolismo , Embrión de Pollo/metabolismo , Pollos/metabolismo , AMP Cíclico/farmacología , Lóbulo Frontal/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Pollos/crecimiento & desarrollo , Lóbulo Frontal/embriología , Lóbulo Frontal/crecimiento & desarrollo , Fosforilación , Fracciones Subcelulares/metabolismo
13.
Brain Res ; 471(2): 259-72, 1988 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-3179751

RESUMEN

The development of calmodulin stimulated protein phosphorylation, with particular reference to calmodulin-stimulated protein kinase II (CMK II), was investigated in 3 subcellular fractions of chicken forebrain: cytosol (S3), crude synaptic plasma membranes (P2-M) and occluded cytosol (P2-S). Changes in the level of calmodulin-stimulated phosphorylation of endogenous proteins occurred over a protracted time course and were not complete until after day 52 post-hatching. By day 15 post-hatching, calmodulin-stimulated phosphoproteins characteristic of embryonic fractions had all disappeared and those characteristic of adult tissue were present but not necessarily at their mature levels. The levels of CMK II were estimated from the autophosphorylation of the alpha-subunit which was the only phosphoprotein present at 53,000 Da in the 3 fractions. Overall, calmodulin-stimulated phosphorylation and CMK II levels were low in embryonic brain and high in adult brain but two specific changes in CMK II were observed during development: (1) although CMK II concentrations increased in both membrane and cytosolic fractions until day 23 the kinase was predominantly cytoplasmic (approximately 75%) until day 23, after which it became increasingly membrane bound so that by day 52 post-hatching the majority of CMK II was present in the synaptic membrane fraction, and (2) the relative concentrations of the alpha- and beta-subunits changed from an alpha:beta-value of approximately 1:1 in the 19 day embryo to approximately 1:2 by 15 days post-hatch after which no further change was seen. The occurrence of major changes in the calmodulin stimulated protein phosphorylation system for up to 6-8 weeks after synapse formation is completed in the forebrain, provides further support for the existence of a synapse maturation phase of neuronal differentiation which is distinct from synapse formation. This phase involves only a specific subset of the developmental changes occurring in the calmodulin-stimulated phosphorylation system.


Asunto(s)
Envejecimiento/metabolismo , Calmodulina/farmacología , Pollos/metabolismo , Lóbulo Frontal/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Embrión de Pollo/metabolismo , Pollos/crecimiento & desarrollo , Lóbulo Frontal/efectos de los fármacos , Lóbulo Frontal/crecimiento & desarrollo , Proteínas del Tejido Nervioso/fisiología , Fosforilación , Fracciones Subcelulares/metabolismo
14.
Brain Res ; 394(1): 37-50, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3756531

RESUMEN

The postnatal development of calmodulin-stimulated phosphorylation of endogenous proteins, in particular the autophosphorylated subunits of the calmodulin-stimulated protein kinase II, were investigated in subcellular fractions of rat cerebral cortex. The major subunit had a mol. wt. of 53,000 Da (designated 50 kDa) and the minor one a mol. wt. of 63,000 Da (designated 60 kDa). The 50-kDa subunit was found to be the only significant phosphoprotein in each fraction and throughout development at its molecular weight. However, the 60-kDa subunit was found to comigrate with other phosphoproteins that accounted for up to 15% of the radioactivity at this molecular weight and which differed between the fractions. 50-kDa autophosphorylation was found to be 3-fold greater in cytoplasmic fractions at day 10 and by adults was evenly distributed between membrane and cytoplasmic fractions. A similar pattern was also found for the total calmodulin-stimulated phosphorylation. Changes in autophosphorylation activity of the 50-kDa subunit were found to represent changes in kinase activity rather than alterations in phosphatase activity. In the membrane, this change was shown to be due to changes in the amount of enzyme. Although in the adult autophosphorylation activity is evenly distributed between membrane and soluble fractions, when differences in phosphatase activity and lack of autophosphorylation activity of the majority of post-synaptic density-associated kinase is taken into account, it is clear that the vast majority of the enzyme is membrane-bound. Phosphorylation of endogenous substrates paralleled the development of 50-kDa subunit autophosphorylation, most of which occurred between day 14 and day 30, a period which follows the most rapid phase of synaptogenesis. This pattern was different from that of the phosphorylation of myelin basic protein and two substrates of the calcium-phospholipid-dependent protein kinase. There was also a change in the ratio of autophosphorylation activity of the 50-kDa and 60-kDa subunits during development which appears to be due to a change in the amount of the subunits themselves. This ratio was the same in all fractions at any one age. We suggest that this change is due to the existence of at least two developmentally regulated isoenzymes in the cortex.


Asunto(s)
Envejecimiento , Calmodulina/metabolismo , Corteza Cerebral/enzimología , Fosfoproteínas/metabolismo , Proteínas Quinasas/clasificación , Animales , Corteza Cerebral/crecimiento & desarrollo , Electroforesis en Gel de Poliacrilamida , Peso Molecular , Fosforilación , Proteínas Quinasas/análisis , Ratas , Ratas Endogámicas , Fracciones Subcelulares/metabolismo
15.
J Pharm Sci ; 69(4): 475-7, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7373553

RESUMEN

A rapid and quantitative method for the determination of pramoxine hydrochloride by high-pressure liquid chromatography is presented. The drug is extracted as the salt from a preparation with a high lipoid composition by partitioning it to the aqueous phase of an ether-methanol-water-acetic acid system. The extract is chromatographed on an octadecylsilane bonded packing with a methanol-water-acetic acid-methanesulfonic acid mobile phase. The time required for each separation is approximately 6 min. Analytical recoveries of 100.4 +/- 1.5% were obtained.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Morfolinas/análisis , Aerosoles , Lípidos
16.
Anat Embryol (Berl) ; 195(4): 311-5, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9108196

RESUMEN

The major components of the actin microfilament system, actin and tropomyosin (Tm), are encoded by multigene families. There are at least 6 actin and over 20 Tm isoforms in mammals. The observation that isoforms are expressed in a tissue-specific manner has encouraged the hypothesis that they contribute to the formation of cell type-specific structures. Recent studies have indicated that certain specific isoforms do play unique structural roles. One nonmuscle actin isoform, beta, is implicated in the regulation of cell spreading and membrane organisation. The intracellular location of beta-actin mRNA has been shown to be regulated by growth factor stimulation of signal transduction pathways. Actin isoforms have also been shown to differ in their contractile properties in both muscle and non-muscle cells. Tropomyosins have been found to show isoform specific regulation in response to cell transformation. This has correlated with the view that some isoforms of tropomyosin promote filament stability whereas others are associated with more dynamic structures. Neuronal development and maturation are accompanied by dynamic spatial sorting of tropomyosin isoforms into different cellular compartments. It is now apparent that isoforms of these proteins perform different structural tasks. The challenge is now to link the significance of spatial sorting to the different physicochemical properties of these isoforms.


Asunto(s)
Actinas/metabolismo , Fibroblastos/metabolismo , Tropomiosina/metabolismo , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Actinas/análisis , Animales , Fibroblastos/química , Humanos , Morfogénesis/fisiología , Contracción Muscular/fisiología , Neuronas/química , Neuronas/metabolismo , ARN Mensajero/metabolismo
17.
Talanta ; 38(8): 913-22, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18965237

RESUMEN

The ultraviolet (UV) photolysis of several classes of nitrogenous pesticides was examined with a view to photo-induced fluorescence detection in flow-injection analysis (FIA) and liquid chromatography. The solvents evaluated as typical reversed-phase mobile phases included water, methanol, and 1:1 mixtures of methanol/water and acetonitrile/water, and methanol/acetonitrilelwater mixtures. Acetone, acetophenone, the surfactant triton X-100, and the photocatalyst titanium dioxide were assessed as photosensitizers to enhance the UV photolysis and fluorescence responses. FIA and liquid chromatographic separations of several pesticides were followed by post-column UV photolysis for the fluorescence detection. Ultraviolet photolysis produces some fluorescent products. The type of photolytic solvent seems to play a significant role. The presence of photosensitizers also affects the fluorescence response of some pesticides. The photochemical transformation products of some of the pesticides are suggested. Analytical figures of merit were evaluated for determination of several pesticides in ground water. The post-column UV photolysis approach for fluorescence detection in liquid chromatography was assessed for several nitrogenous pesticides in ground water samples at ng/g concentrations.

18.
J Forensic Sci ; 46(5): 1025-32, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11569540

RESUMEN

A rapid, accurate, precise, reproducible, economical, and environmentally gentle method using capillary electrophoresis (CE) is presented for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine in seized drugs. The methodology uses a 32 cm by 50 microm capillary (length to detector 23.5 cm) with a commercially available buffer kit and diode array UV detection. Dynamic coating of the capillary surface is accomplished by flushing with base for 1 min, a proprietary polycation for 1 min, and then a proprietary polyanion for 2 min. This approach provides a relatively high and stable electroosmotic flow (EOF), even at low pHs. The background electrolyte (BGE) contains 75 mM phosphate buffer (pH 2.5) with the same polyanion as above. Using this methodology, amphetamine, methamphetamine, MDA, MDMA, MDEA, and an internal standard (n-butylamphetamine) are baseline resolved in less than 5 min. The run-to-run migration time %RSDs and peak area %RSDs are typically <0.3% and <2.1%, respectively. The day-to-day and capillary-to-capillary migration time %RSDs are <1.5% and <2.1%, respectively. The %RSDs of the relative migration times compared with the internal standard on a day-to-day and capillary-to-capillary basis are <0.2% and <0.06%, respectively. The linear dynamic range using peak areas range from 0.003 to 0.10 mg/mL. The correlation coefficients are >0.9998, with all calibration curves passing at or near the origin. Similar data are obtained for cocaine and its internal standard henyltoloxamine. None of the compounds usually encountered in illicit samples interfere with the target compound (e.g., methamphetamine and cocaine) or the internal standard. Quantitative results for synthetic mixtures and seized exhibits are in good agreement with actual values, and also with results obtained from other techniques. The relatively high EOF for the dynamically coated capillary system allows for the screening of basic, acidic, and neutral adulterants in drug seizures; identification is facilitated by the use of automated UV library searches.

19.
J Gerontol Nurs ; 17(10): 23-7, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1940105

RESUMEN

1. Psychological or physiological stressors cause changes within the body through the action of the hypothalamus. 2. There are several techniques for stress management, including progressive muscle relaxation and guided imagery. 3. The nurse can teach stress management techniques to the elderly using teaching modifications to respond to changes due to aging. 4. The nurse can teach stress management in various settings to clients who have a nursing diagnosis such as anxiety, alteration in comfort, or sleep pattern disturbance.


Asunto(s)
Enfermería Geriátrica , Educación del Paciente como Asunto , Estrés Psicológico/prevención & control , Anciano , Humanos , Imaginación , Relajación Muscular
20.
Eur Psychiatry ; 29(4): 203-10, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24054518

RESUMEN

PURPOSE: 22q11.2 deletion syndrome (22q11.2DS) and Williams syndrome (WS) are common neurogenetic microdeletion syndromes. The aim of the present study was to compare the neuropsychiatric and neurocognitive phenotypes of 22q11.2DS and WS. METHODS: Forty-five individuals with 22q11.2DS, 24 with WS, 22 with idiopathic developmental disability (DD) and 22 typically developing (TD) controls were compared for the rates of psychiatric disorders as well as cognitive executive and visuospatial functions. RESULTS: We found that while anxiety, mood and disruptive disorders had an equally high prevalence among individuals with 22q11.2DS, WS and DDs, the 22q11.2DS group had the highest rates of psychotic disorders and the WS group had the highest rates of specific phobia. We also found that the WS group demonstrated more severe impairments in both executive and visuospatial functions than the other groups. WS and 22q11.2DS subjects had worse Performance-IQ than Verbal-IQ, a feature typical of non-verbal learning disorders. CONCLUSION: These findings offer a wide perspective on unique versus common phenotypes in 22q11.2DS and WS.


Asunto(s)
Síndrome de DiGeorge/psicología , Síndrome de Williams/psicología , Adolescente , Estudios de Casos y Controles , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/genética , Síndrome de DiGeorge/complicaciones , Síndrome de DiGeorge/fisiopatología , Función Ejecutiva , Femenino , Humanos , Masculino , Trastornos Mentales/etiología , Trastornos Mentales/genética , Pruebas Neuropsicológicas , Fenotipo , Escalas de Valoración Psiquiátrica , Percepción Espacial , Escalas de Wechsler , Síndrome de Williams/complicaciones , Síndrome de Williams/fisiopatología
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