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1.
Ned Tijdschr Tandheelkd ; 126(11): 599-606, 2019 Nov.
Artículo en Holandés | MEDLINE | ID: mdl-31730137

RESUMEN

To improve oral health for frail and care-dependent older people, both intra- and extramurally, in the Euregio Rhine-Waal area in the Netherlands and Germany, we inventoried barriers to oral care for the target group according to the literature, the organisation of oral care in both countries and the implications of this organisation for daily and professional (oral) healthcare and oral care. Results show most identified barriers are common to both countries, but the organisation of oral healthcare differs in both countries. The main differences lie in the financing and organisation of oral care in the intramural situation. In the Netherlands, this is to a large degree regulated and organised on the basis of the Chronic Care Act (Wlz), using the Verenso Oral Care Directive for care-dependent clients as a base for enforcement. In Germany, on the other hand, the provision of oral care in the home situation is more effectively facilitated. In both countries, various initiatives have recently been employed to improve, among other things, information supply, education and financing of oral healthcare.


Asunto(s)
Atención a la Salud , Cuidado Dental para Ancianos , Salud Bucal , Anciano , Anciano de 80 o más Años , Anciano Frágil , Alemania , Humanos , Países Bajos
2.
Br J Surg ; 104(8): 990-1002, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28542731

RESUMEN

BACKGROUND: The impact of chemotherapy-associated liver injury (CALI) on postoperative outcome in patients undergoing partial hepatectomy for colorectal liver metastases (CRLM) remains controversial. The objective of this study was to clarify the effect of CALI (sinusoidal dilatation (SD), steatosis and steatohepatitis) on postoperative morbidity and mortality by investigating a large data set from multiple international centres. METHODS: PubMed and Embase were searched for studies published between 1 January 2004 and 31 December 2013 with keywords 'chemotherapy', 'liver resection', 'outcome' and 'colorectal metastases' to identify potential collaborating centres. Univariable and multivariable analyses were performed using binary logistic regression models, with results presented as odds ratios (ORs) with 95 per cent confidence intervals. RESULTS: A consolidated database comprising 788 patients who underwent hepatectomy for CRLM in eight centres was obtained. In multivariable analyses, severe SD was associated with increased major morbidity (Dindo-Clavien grade III-V; OR 1·73, 95 per cent c.i. 1·02 to 2·95; P = 0·043). Severe steatosis was associated with decreased liver surgery-specific complications (OR 0·52, 95 per cent c.i. 0·27 to 1·00; P = 0·049), whereas steatohepatitis was linked to an increase in these complications (OR 2·08, 1·18 to 3·66; P = 0·012). Subgroup analysis showed that lobular inflammation was the sole component associated with increased overall morbidity (OR 2·22, 1·48 to 3·34; P = 0·001) and liver surgery-specific complications (OR 3·35, 2·11 to 5·32; P < 0·001). Finally, oxaliplatin treatment was linked to severe SD (OR 2·74, 1·67 to 4·49; P < 0·001). CONCLUSION: An increase in postoperative major morbidity and liver surgery-specific complications was observed after partial hepatectomy in patients with severe SD and steatohepatitis. Postoperative liver failure occurred more often in patients with severe SD.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/complicaciones , Neoplasias Colorrectales , Hepatectomía/métodos , Neoplasias Hepáticas/cirugía , Enfermedad Hepática Inducida por Sustancias y Drogas/mortalidad , Hígado Graso/inducido químicamente , Hígado Graso/mortalidad , Femenino , Hepatectomía/mortalidad , Humanos , Tiempo de Internación , Fallo Hepático Agudo/etiología , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología
3.
Environ Monit Assess ; 186(11): 7617-30, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25124990

RESUMEN

Monitoring changes in land cover and the subsequent environmental responses are essential for water quality assessment, natural resource planning, management, and policies. Over the last 75 years, the Lake Issaqueena watershed has experienced a drastic shift in land use. This study was conducted to examine the changes in land cover and the implied changes in land use that have occurred and their environmental, water quality impacts. Aerial photography of the watershed (1951, 1956, 1968, 1977, 1989, 1999, 2005, 2006, and 2009) was analyzed and classified using the geographic information system (GIS) software. Seven land cover classes were defined: evergreen, deciduous, bare ground, pasture/grassland, cultivated, and residential/other development. Water quality data, including sampling depth, water temperature, dissolved oxygen content, fecal coliform levels, inorganic nitrogen concentrations, and turbidity, were obtained from the South Carolina (SC) Department of Health and Environmental Control (SCDHEC) for two stations and analyzed for trends as they relate to land cover change. From 1951 to 2009, the watershed experienced an increase of tree cover and bare ground (+17.4 % evergreen, +62.3 % deciduous, +9.8 % bare ground) and a decrease of pasture/grassland and cultivated land (-42.6 % pasture/grassland and -57.1 % cultivated). From 2005 to 2009, there was an increase of 21.5 % in residential/other development. Sampling depth ranged from 0.1 to 0.3 m. Water temperature fluctuated corresponding to changing air temperatures, and dissolved oxygen content fluctuated as a factor of water temperature. Inorganic nitrogen content was higher from December to April possibly due to application of fertilizers prior to the growing season. Turbidity and fecal coliform bacteria levels remained relatively the same from 1962 to 2005, but a slight decline in pH can be observed at both stations. Prior to 1938, the area consisted of single-crop cotton farms; after 1938, the farms were abandoned, leaving large bare areas with highly eroded soil. Starting in 1938, Clemson reforested almost 30 % of the watershed. Currently, three fourths of the watershed is forestland, with a limited coverage of small farms and residential developments. Monitoring water quality is essential in maintaining adequate freshwater supply. Water quality monitoring focuses mainly on the collection of field data, but current water quality conditions depend on the cumulative impacts of land cover change over time.


Asunto(s)
Monitoreo del Ambiente , Lagos/química , Análisis Espacio-Temporal , Agricultura/estadística & datos numéricos , Conservación de los Recursos Naturales , Fertilizantes/análisis , Fertilizantes/estadística & datos numéricos , Sistemas de Información Geográfica , Nitrógeno/análisis , South Carolina , Árboles , Calidad del Agua
4.
J Physiol ; 587(Pt 17): 4199-211, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19622603

RESUMEN

A world-wide series of epidemiological and experimental studies have demonstrated that there is an association between being small at birth, accelerated growth in early postnatal life and the emergence of insulin resistance in adult life. The aim of this study was to investigate why accelerated growth occurs in postnatal life after in utero growth restriction. Samples of quadriceps muscle were collected at approximately 140 days gestation (term approximately 150 days gestation) from normally grown fetal lambs (Control, n = 7) and from growth restricted fetal lambs (placentally restricted: PR, n = 8) and from Control (n = 14) and PR (n = 9) lambs at 21 days after birth. The abundance of the insulin and IGF1 receptor protein was higher in the quadriceps muscle of the PR fetus, but there was a lower abundance of the insulin signalling molecule PKC, and GLUT4 protein in the PR group. At 21 days of postnatal age, insulin receptor abundance remained higher in the muscle of the PR lamb, and there was also an up-regulation of the insulin signalling molecules, PI3Kinase p85, Akt1 and Akt2 and of the GLUT4 protein in the PR group. Fetal growth restriction therefore results in an increased abundance of the insulin receptor in skeletal muscle, which persists after birth when it is associated with an upregulation of insulin signalling molecules and the glucose transporter, GLUT4. These data provide evidence that the origins of the accelerated growth experienced by the small baby after birth lie in the adaptive response of the growth restricted fetus to its low placental substrate supply.


Asunto(s)
Desarrollo Fetal , Retardo del Crecimiento Fetal/metabolismo , Insulina/metabolismo , Modelos Biológicos , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/metabolismo , Transducción de Señal , Animales , Femenino , Embarazo , Ovinos
5.
Dalton Trans ; 46(7): 2249-2254, 2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28128830

RESUMEN

One-dimensional 27Al, 23Na Magic-Angle-Spinning (MAS) NMR and 27Al Multiple-Quantum Magic-Angle-Spinning NMR (MQMAS) measurements are reported for the δ-isomer of the Al13 Keggin structure at high spinning speed and 14.1 T field. Values for the CQ and η parameters are on the same scale as those seen in other isomers of the Al13 structure. Density functional theory (DFT) calculations are performed for comparison to the experimental fits using the B3PW91/6-31+G* and PBE0/6-31+G* levels of theory, with the Polarizable Continuum Model (PCM).

6.
Trends Neurosci ; 14(10): 468-73, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1722367

RESUMEN

It is currently believed that sexual differentiation of the brain is mediated entirely by the epigenetic action of gonadal steroids during a critical period of development. Ingrid Reisert and Christoph Pilgrim review sexual dimorphisms of monoaminergic systems, which also appear to be generated by sex steroids. However, there are a number of observations that are not explainable by the 'androgen theory of sexual differentiation'. Results obtained from cultures of embryonic rat brain tissue appear to indicate that dopaminergic neurons may develop morphological and functional sex differences in the absence of sex steroids. Hormone-independent and -dependent developmental processes may affect diencephalic and mesencephalic dopaminergic neurons in a regionally diverse fashion. Factors other than sex steroids need to be examined. It is possible that some sexual dimorphisms in the nervous system may develop under primary genetic control.


Asunto(s)
Monoaminas Biogénicas/fisiología , Neuronas/fisiología , Diferenciación Sexual/genética , Animales , Encéfalo/embriología , Femenino , Humanos , Embarazo
7.
J Natl Cancer Inst ; 85(2): 112-20, 1993 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-8418300

RESUMEN

BACKGROUND: Despite the effectiveness of breast cancer screening for women older than 50 years of age, only about one third of these women in the United States receive annual mammography. PURPOSE: This study was designed to determine if a community-wide intervention could increase use of mammography screening for breast cancer. Secondary end points were determination of changes in women's knowledge and attitudes toward mammography and physicians' self-reported screening practices. METHODS: We conducted a controlled study from January 1987 through January 1990 in two eastern North Carolina communities--New Hanover County (the experimental community) and Pitt County (the control community). Before development and implementation of the intervention program in New Hanover County and after the program had been in operation for 1 year, 500 women of ages 50-74 years and all primary-care physicians in each community were interviewed by telephone. In these interviews, we determined the use of mammography for breast cancer screening and the knowledge and attitudes about it. We also established the number of screening mammograms performed in 1987 and 1989 in each county and reviewed medical records to determine the percentage of women the physicians had referred for mammograms. RESULTS: The percentage of women who reported receiving a mammogram in the previous year increased from 35% to 55% in the experimental community and from 30% to 40% in the control community (difference of differences, 10%; P = .03 after adjustment for race, education, age, and having a regular doctor; 95% confidence interval, 1%-18%). Increases were greater in New Hanover County regardless of age, race, income, and education. However, the increase was less for Black women than for White women, both overall and in most demographic subgroups. The total number of mammograms performed increased 89% in the experimental community and 45% in the control community. Women's knowledge about mammography changed little, but the intention to get a mammogram increased 30% in New Hanover County, compared with a 17% increase in Pitt County--a statistically significant difference (P < .01). Physician reports and medical record reviews in the two communities showed similar increases in the number of mammograms ordered. CONCLUSIONS: A community-wide effort to increase use of breast cancer screening was successful, but more work must be done to reach the National Cancer Institute's goal of annual mammograms for 80% of women of ages 50-74.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/prevención & control , Mamografía/estadística & datos numéricos , Factores de Edad , Anciano , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Tamizaje Masivo , Persona de Mediana Edad , North Carolina , Población Rural , Factores Socioeconómicos
8.
Eur J Trauma Emerg Surg ; 42(6): 671-675, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26626871

RESUMEN

INTRODUCTION: The management of haemodynamically stable patients who present following a penetrating abdominal injury (PAI) remains variable between mandatory surgical exploration and more selective non-operative approaches. The primary aim of this study was to assess compliance with an algorithm guiding selective non-operative management of haemodynamically stable patients with PAI. The secondary aim was to examine the association between compliance and unnecessary laparotomies. METHODS: This was a retrospective cohort study involving all patients with PAI that presented to a major trauma centre from January 2007 to December 2011. Data were extracted from the trauma registry and patients' electronic medical records. RESULTS: There were 189 patients included in the study, of which 79 (41.8 %) patients complied with the algorithm. The laparotomy rate in the setting of algorithm compliance was significantly lower than algorithm non-compliance (12.7 vs. 68.2 %; p < 0.01) as were unnecessary laparotomy rates (0 vs. 33.3 %; p = 0.03). CONCLUSION: Among haemodynamically stable patients presenting with PAI, compliance with an algorithm guiding selective non-operative management was low, but associated with lower laparotomy and lower unnecessary laparotomy rates. Improved compliance with algorithms directed towards selective non-operative management of PAI should be encouraged with stringent vigilance towards patient safety.


Asunto(s)
Traumatismos Abdominales/terapia , Adhesión a Directriz , Heridas Punzantes/terapia , Adulto , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Sistema de Registros , Estudios Retrospectivos , Centros Traumatológicos , Procedimientos Innecesarios/estadística & datos numéricos , Victoria
9.
J Comp Neurol ; 211(4): 427-31, 1982 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-7174904

RESUMEN

The present study was undertaken to provide an explanation for previous autoradiographic results suggesting a several times higher rate of synthesis of glycoconjugates per unit volume of hypothalamic glia than of neurons. Volume densities, specific surfaces (surface-volume ratios), and relative surfaces (contribution of the surface of a tissue element to the total surface of the tissue) were assessed. Neuronal elements occupy about 74% and glial elements about 8% of the total volume. The specific surface, i.e., the amount of plasma membrane per unit volume of structure, is more than 30 times higher in the neuropil than in the neuronal perikaryal fraction. The largest specific surface is found with (unmyelinated) axons and astroglial processes. The specific surface of the average astrocyte is about twice that of the average neuron. If the surface of the entire cell is considered in relation to the perikaryal volume only, this ratio is about seven times as large for glial cells as for neurons. It follows that an astrocyte perikaryon has to renew a several times larger plasma membrane than a neuron, which can account for the above differences in perikaryal synthesis rates of glycoconjugates.


Asunto(s)
Núcleo Supraóptico/citología , Animales , Astrocitos/citología , Glicoproteínas/biosíntesis , Masculino , Microscopía Electrónica , Proteínas del Tejido Nervioso/biosíntesis , Neuroglía/citología , Neuronas/citología , Ratas , Ratas Endogámicas , Núcleo Supraóptico/metabolismo , Núcleo Supraóptico/ultraestructura
10.
J Comp Neurol ; 176(3): 453-66, 1977 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-915048

RESUMEN

Incorporation of 3H-fucose into hypothalamic tissue of rats was studied between ten minutes and seven days after intraventricular injection. In EM autoradiographs grain densities over perikarya of neurons, astro-, and oligodendroglia, and neuropil were evaluated. Grain densities were consistently higher over both types of glial cells as compared to neurons. The glia/neuron ratio was especially high after short experimental intervals and declined with increasing time intervals. Concomitantly there was an increase of grain density over the neuropil. The discussion concentrates on the methodical aspects which have to be considered in interpreting the autoradiographic data. It is concluded that both astroglia and oligodendroglia exhibit a considerably higher synthesis rate of glycoproteins per unit volume than nerve cells. The implications of the results for the interpretation of biochemical data on glycoprotein metabolism of brain tissue are discussed.


Asunto(s)
Fucosa/metabolismo , Glicoproteínas/biosíntesis , Hipotálamo/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Animales , Astrocitos/metabolismo , Autorradiografía , Hipotálamo/citología , Masculino , Microscopía Electrónica , Neuronas/metabolismo , Oligodendroglía/metabolismo , Ratas , Núcleo Supraóptico/citología , Núcleo Supraóptico/metabolismo
11.
J Comp Neurol ; 229(1): 121-8, 1984 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-6490973

RESUMEN

Both hypoglossal nuclei were examined by electron microscope stereology after unilateral axotomy. The principal aim of this study was a quantitative assessment of the accompanying glial reaction. Volume densities (%) of neuronal and glial perikarya, as well as their processes, were evaluated in terms of volume plus surface densities (mm-1). In addition, specific surfaces (surface to volume ratio) of these neuronal and glial processes were assessed. First, a temporary decrease of dendritic volume density was detected on the ipsilateral side only. Further, the astrocytic reaction displayed differences between stem and lamellar processes. One day after axotomy, a bilateral decrease of volume density, as well as surface density of stem processes, was observed, yet their normal dimensions soon were reestablished. However, a more severe lamellar process reaction was evident. During the first 4 days, a significant increase of volume density and surface density was apparent. In the contralateral hypoglossal nucleus, this glial reaction also occurred but disappeared by day 14, whereas the ipsilateral nucleus continued to display a severe reaction of lamellar processes, only returning to normal status at day 77. In addition, a transient, severe reaction of presumptive microglia was established by employing the volume density and surface density quantitation procedure. Nevertheless, in comparison with the volume and surface contribution of astrocytic processes, the presumed microglial component was minimal. This study indicates a two-step involvement of astrocytes in regenerative repair. Namely, the first phase seems to result in an increase of lamellar processes through reshaping of the stem process.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Traumatismos del Nervio Hipogloso , Bulbo Raquídeo/patología , Neuronas Motoras/patología , Regeneración Nerviosa , Neuroglía/patología , Animales , Astrocitos/patología , Nervio Hipogloso/patología , Nervio Hipogloso/ultraestructura , Masculino , Bulbo Raquídeo/ultraestructura , Ratas , Ratas Endogámicas
12.
J Comp Neurol ; 246(4): 467-77, 1986 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-2422230

RESUMEN

The projections from the claustrum to the cerebral cortex in the rat were examined by means of retrogradely transported fluorescent tracers Fast Blue (FB) and Diamidino Yellow dihydrochloride (DY), injected in the prefrontal, motor, somatosensory, auditory, and visual fields. In all cases, substantial numbers of retrogradely labeled neurons were observed in the ipsilateral and moderate to scant numbers in the contralateral claustrum insulare. Symmetrical bilateral injections of FB and DY as well as simultaneous injections of the tracers in the motor and visual cortex of the same hemisphere revealed no double-labeled neurons in the claustrum. The following conclusions may be drawn: The claustral projections to the motor, somatosensory, and visual cortex are prominent. The projection to the prefrontal cortex is less substantial and that to the auditory cortex is relatively modest. The claustrocortical connections lack the clear-cut topographic pattern of the thalamic nuclei but are, to some degree, preferentially arranged, albeit with considerable overlapping of the subpopulations of corticopetal neurons, a coarse anteroposterior topographic distribution appears to exist also in rodents. Neurons contributing to the claustrocortical connection project either ipsilaterally or contralaterally but not bilaterally. Projections to different cortical fields of one hemisphere also originate from separate claustral neurons.


Asunto(s)
Transporte Axonal , Ganglios Basales/anatomía & histología , Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Lateralidad Funcional , Animales , Corteza Auditiva/anatomía & histología , Ganglios Basales/citología , Transporte Biológico , Corteza Cerebral/citología , Lóbulo Frontal/anatomía & histología , Lateralidad Funcional/fisiología , Masculino , Corteza Motora/anatomía & histología , Vías Nerviosas/anatomía & histología , Neuronas/citología , Ratas , Ratas Endogámicas , Corteza Somatosensorial/anatomía & histología , Corteza Visual/anatomía & histología
13.
J Comp Neurol ; 323(2): 299-304, 1992 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-1357008

RESUMEN

On the basis of observations on dopaminergic neurons developing in gender-specific cultures of embryonic rat mesencephalon, we have hypothesized that as yet unknown sexual dimorphisms might be found in projection areas of dopaminergic neurons. Therefore we searched for possible sex differences in the striatum during the period when massive ingrowth of mesencephalic afferents occurs and the striatal gamma-aminobutyric acid (GABA)ergic neurons differentiate. Male and female rats of embryonic days (E) 16, 18, 20, and 21 were fixed by perfusion through the heart. Vibratome sections were cut from the striatal anlage and sequentially immunostained for GABA by the immunogold-silver technique and tyrosine hydroxylase (TH) by the avidin-biotin-peroxidase method. Ultrathin sections were scanned for numbers of GABA- and TH-immunoreactive (IR) elements. Densities of TH-IR axons as well as of GABA-IR cell body profiles progressed with time. Contacts between TH-IR axons and GABA-IR and immunonegative cells were observed as early as E-16, increasing in numbers toward later stages. Throughout prenatal development, female striata displayed higher densities of both TH-IR axon and GABA-IR cell body profiles than male ones. This is the first report of a distinct anatomical sex difference regarding two major components of a key center of motor control. Prenatal sexual differentiation of the striatum may lead to a sexually dimorphic extrapyramidal circuitry, the existence of which, in the adult, is suggested by experimental and clinical data.


Asunto(s)
Cuerpo Estriado/fisiología , Dopamina/fisiología , Fibras Nerviosas/fisiología , Neuronas/fisiología , Ácido gamma-Aminobutírico/fisiología , Animales , Cuerpo Estriado/citología , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Caracteres Sexuales , Tirosina 3-Monooxigenasa/metabolismo
14.
Neuroscience ; 17(1): 157-65, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3008023

RESUMEN

The development of dopaminergic and noradrenergic neurons in dissociation cultures of mesencephalon and rhombencephalon obtained from 18-day-old rat fetuses was characterized by their capacity to take up and release catecholamines. In both types of cultures, uptake of [3H]dopamine and [3H]noradrenaline was obtained which could be inhibited by reserpine. Autoradiographic studies demonstrated an almost exclusive neuronal localization of the labeled catecholamines. The transmitters could be released by depolarization with K+ in a Ca2+-dependent manner during the entire cultivation period. In contrast, catecholamine uptake by cultures of neocortex was minimal, could not be inhibited by reserpine, and the accumulated radioactivity could not be released upon depolarization. These points provide evidence for an active accumulation of the exogenous transmitters and for the presence of stimulus-secretion coupling in a distinct population of neurons of both brain stem cultures. Striking differences between the two brain stem cultures concerned their sensitivity to desmethylimipramine and benztropine as well as the time course of the development of the uptake capacity. Desmethylimipramine inhibited the uptake of both catecholamines in rhombencephalic, but not in mesencephalic cultures. The reverse was true for benztropine. It is concluded that cultures of rhombencephalon contain predominantly noradrenergic, and those of mesencephalon dopaminergic cells. Comparison of the uptake behaviour suggested that noradrenergic neurons mature considerably later than dopaminergic neurons. The results show that dissociation cultures of mid- and hindbrain, inspite of their heterogeneous composition, can serve as valuable models for the study of development and function of dopaminergic and noradrenergic neurons, respectively.


Asunto(s)
Encéfalo/embriología , Dopamina/fisiología , Norepinefrina/fisiología , Fibras Adrenérgicas/fisiología , Animales , Autorradiografía , Benzotropina/farmacología , Encéfalo/metabolismo , Células Cultivadas , Desipramina/farmacología , Mesencéfalo/embriología , Ratas , Transmisión Sináptica
15.
Neuroscience ; 32(1): 133-9, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2586746

RESUMEN

Serotonin is believed to modulate neuronal differentiation during early stages of brain development. In order to assess basic functional requirements for such a role, it was investigated how early serotoninergic neurons mature with respect to transmitter storage and stimulus-secretion coupling. Dissociated cell cultures were raised from embryonic rat rhombencephalon obtained at gestational day 14 and cultured for 3-8 days, which may roughly correspond to the prenatal period in vivo. Because of a possible involvement of serotonin in processes leading to sexual differentiation of the brain, gender-specific cultures were raised in addition and treated with sex steroids. Sensitivity of [3H]serotonin uptake to fluoxetine could already be observed at 3 days in vitro. Vesicular storage as probed with reserpine and nigericin, and the capability of releasing preaccumulated serotonin in a Ca2+-dependent manner were also present as early as 3 days in vitro. Seven per cent of the pre-accumulated transmitter could be released per minute upon stimulation with 54 mM K+. Immunocytochemical and autoradiographic preparations demonstrated that, after the same short culture period, the neurons had formed large fiber networks. No differences could be detected regarding any of the above parameters between female and male serotonin neurons and between cultures treated with and without estradiol, testosterone and dihydrotestosterone. It is concluded that, in contrast to other neuronal phenotypes, serotoninergic neurons are functionally mature when or shortly after they are taken into culture, i.e. around gestational day 14. The functional competence of prenatal serotonin systems should be a prerequisite for their suspected role in modulating neural development at pre and postsynaptic sites. The present results provide no evidence for the occurrence of a sexual dimorphism of serotonin neurons at this early developmental stage.


Asunto(s)
Desarrollo Embrionario y Fetal , Rombencéfalo/metabolismo , Serotonina/farmacocinética , Animales , Células Cultivadas , Femenino , Edad Gestacional , Masculino , Ratas , Ratas Endogámicas , Rombencéfalo/embriología , Serotonina/fisiología , Factores Sexuales
16.
Neuroscience ; 7(5): 1317-22, 1982 May.
Artículo en Inglés | MEDLINE | ID: mdl-7110589

RESUMEN

The immunocytochemical visualization of neuron-specific enolase, which is a marker protein for differentiated neurons, was applied to follow the differentiation of preoptic and septal neurons in dissociated cultures. From 4 to 24 days in vitro, the relative numbers of stained neurons were counted and the staining intensity of individual neurons determined by absorbency measurements using a television-based densitometer. Whereas few stained cells could be observed at 4 DIV, 80% of the neurons were neuron-specific enolase-positive at 13 days in vitro. This value remained constant up to 24 days in vitro. The density of the immunoreaction product increased dramatically from 13 to 17 days in vitro and was still higher at 24 days in vitro. The glial and ependymal cells of the carpet, as well as neuroblasts, remained unstained. Comparison with morphological observations and immunocytochemical demonstration of neuronal peptides made earlier shows that expression of neuron-specific enolase closely parallels neuronal differentiation. These observations indicate that cultures derived from preoptic and septal neurons represent a viable model system for the study of neuronal maturation in vitro.


Asunto(s)
Hipotálamo/enzimología , Isoenzimas/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Área Preóptica/enzimología , Núcleos Septales/enzimología , Animales , Agregación Celular , Diferenciación Celular , Técnicas de Cultivo , Dendritas/enzimología , Neuronas/citología , Neuronas/enzimología , Área Preóptica/citología , Ratas , Núcleos Septales/citología
17.
Neuroscience ; 24(3): 877-83, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3380305

RESUMEN

The activity of the pentose phosphate shunt was assessed under basal conditions in subregions of the hippocampus by measuring the uptake and retention of [1-14C]glucose and [6-14C]glucose and their 14C-labelled metabolites. The relative and absolute retention of carbon-14 from each of the two compounds was nearly identical in all regions examined. For each compound, the highest accumulation of 14C occurred in the granule cell layer of the dentate gyrus and in the pyramidal cell layer. Relatively high retention of radioactivity was also found in the molecular layer of dentate gyrus and in the stratum lacunosum-molecular. The stratum radiatum and stratum oriens contained the lowest levels of radioactivity among hippocampal regions. The equal retention of radioactivity from [1-14C]glucose and [6-14C]glucose implies that pentose phosphate shunt activity is very low throughout the hippocampus under the conditions of this study. The uptake and retention of radioactivity was evaluated in different hippocampal regions 10 or 30 min following intravenous injection of [1-14C]glucose. Although there was significantly more radioactivity at 30 min than at 10 min, the same topographic pattern of radioactivity within the hippocampus was observed in rats after both survival periods, indicating that an equal fraction of the [1-14C]glucose utilized in different hippocampal regions is oxidized to 14CO2 under these conditions. Most regions of high glucose utilization in the hippocampus determined with [1-14C]glucose and [6-14C]glucose correspond to regions of intense histochemical staining for cytochrome oxidase reported in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Glucosa/farmacocinética , Hipocampo/metabolismo , Animales , Autorradiografía , Radioisótopos de Carbono , Masculino , Ratas , Ratas Endogámicas , Factores de Tiempo
18.
Neuroscience ; 74(2): 453-60, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8865196

RESUMEN

The early dopaminergic input from the midbrain may play an important role in the development of the basal ganglia. We therefore investigated whether and how dopamine affects the morphogenesis of striatal target neurons. Dissociated cell cultures of embryonic day 17 rat striatum were raised for seven days. Cells were then incubated with dopamine or various receptor-specific ligands for 1 h. At various times after termination of the treatment, cells were immunostained for growth-associated protein-43. Morphological parameters including numbers of growth cones, length of neurites, number of bifurcations, and neuronal soma size were assessed by means of a computer-based morphometric device. Treatment with dopamine in low concentrations as well as with the D1-like receptor agonist SKF 38393 increased the numbers of growth cones and neurite length and arborization. The morphogenetic effect took several hours to evolve and remained stable for at least 24 h. It could be blocked by the D1-like receptor antagonist SCH 23390 or by cycloheximide but not by pretreatment of the cultures with tetrodotoxin. The D2-like receptor agonist quinpirole had no effect on the morphological parameters and did not contribute to that of SKF 38393. Dopamine and SKF 38393 but not quinpirole also induced an increase in the number of neurons immunoreactive for Fos-like proteins. However, this effect was restricted to growth-associated protein-43-negative neurons. This is the first observation of a positive regulatory effect of D1-like receptors on neuronal morphogenesis. We conclude that the changes reflect true differentiation rather than short-term modulation of cellular properties and that c-fos induction is not an obligatory step in the transduction pathway coupling D1-like receptors to neurite outgrowth. Our results suggest that the differentiation of embryonic striatal neurons is promoted by the dopaminergic nigrostriatal projection through D1-like receptors.


Asunto(s)
2,3,4,5-Tetrahidro-7,8-dihidroxi-1-fenil-1H-3-benzazepina/farmacología , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/crecimiento & desarrollo , Morfogénesis/efectos de los fármacos , Receptores de Dopamina D1/efectos de los fármacos , Animales , Células Cultivadas , Inmunohistoquímica , Ratas , Ratas Sprague-Dawley
19.
Neuroscience ; 17(1): 99-106, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3960318

RESUMEN

Using high resolution autoradiography, the accumulation of radioactivity after intravenous injection of [1-14C]glucose was measured in the corpus callosum, hippocampus, dorsal hippocampal commissure, somatosensory cortex, inferior colliculus and pontine periaqueductal grey. Autoradiograms were prepared by thaw-mounting 4 micron frozen sections on nuclear emulsion-coated slides, and were evaluated quantitatively with a computer-assisted video system for automated counting of silver grains. In all brain regions examined, silver grain densities were greater in rats killed 30 min after injection of [1-14C]glucose compared to rats killed 10 min after injection. After intravenous injection of [1-14C]glucose or 2-deoxy[14C]glucose, the relative uptake and retention of radioactivity in different hippocampal subregions was compared. Striking differences were found in the hippocampus between 2-deoxy[14C]glucose and [1-14C]glucose autoradiograms. After injection of 2-deoxy[14C]glucose, there were large variations in the uptake and retention of radioactivity among different pyramidal cell fields. The CA 3 pyramidal cell field retained considerably more radioactivity than other pyramidal cell fields after injection of 2-deoxy[14C]glucose, while after injection of [1-14C]glucose, the retention of radioactivity was similar in all pyramidal cell fields. After [1-14C]glucose injection, the dentate gyrus contained relatively high levels of radioactivity and more 14C accumulated in the granular layer, compared to the molecular layer. In contrast, after 2-deoxy[14C]glucose injection, there was uniformly less radioactivity throughout the dentate gyrus when compared to rats injected with [1-14C]glucose and there was no preferential accumulation of 2-deoxy[14C]glucose in the granular layer compared to the molecular layer.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Desoxiazúcares/metabolismo , Desoxiglucosa/metabolismo , Glucosa/metabolismo , Hipocampo/metabolismo , Animales , Autorradiografía , Cuerpo Calloso/metabolismo , Colículos Inferiores/metabolismo , Masculino , Sustancia Gris Periacueductal/metabolismo , Ratas , Corteza Somatosensorial/metabolismo
20.
J Histochem Cytochem ; 37(2): 241-7, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2492046

RESUMEN

We report that a monoclonal antibody directed against phosphorylated neurofilaments (SMI 31) recognizes nuclear antigens present in embryonic but not in adult neural cells. On Western blots, the antibody reacts with four proteins of apparent MW 35, 37, 52/54, and 250 KD which are found exclusively in developing brain tissue. These nuclear antigens are expressed by glial and neuronal cells. Both nuclear staining and immunoreactive proteins decrease with ongoing in vitro differentiation. A computer search for proteins that share the epitope recognized by antibody SMI 31 did not yield any proteins of known nuclear localization that exhibit the same molecular weights and solubility characteristics as the above immunoreactive proteins. We conclude that antibody SMI 31 recognizes hitherto unknown nuclear proteins which, in neural cells, are developmentally regulated.


Asunto(s)
Encéfalo/embriología , Núcleo Celular/inmunología , Proteínas de Filamentos Intermediarios/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Western Blotting , Diferenciación Celular , Células Cultivadas , Peso Molecular , Proteínas de Neurofilamentos , Ratas
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