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1.
Gynecol Oncol ; 143(2): 264-269, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27586894

RESUMEN

OBJECTIVES: Computed tomography (CT) is an essential part of preoperative planning prior to cytoreductive surgery for primary and relapsed epithelial ovarian cancer (EOC). Our aim is to correlate pre-operative CT results with intraoperative surgical and histopathological findings at debulking surgery. METHODS: We performed a systematic comparison of intraoperative tumor dissemination patterns and surgical resections with preoperative CT assessments of infiltrative disease at key resection sites, in women who underwent multivisceral debulking surgery due to EOC between January 2013 and December 2014 at a tertiary referral center. The key sites were defined as follows: diaphragmatic involvement(DI), splenic disease (SI), large (LBI) and small (SBI) bowel involvement, rectal involvement (RI), porta hepatis involvement (PHI), mesenteric disease (MI) and lymph node involvement (LNI). RESULTS: A total of 155 patients, mostly with FIGO stage IIIC disease (65%) were evaluated (primary=105, relapsed=50). Total macroscopic cytoreduction rates were: 89%. Pre-operative CT findings displayed high specificity across all tumor sites apart from the retroperitoneal lymph node status, with a specificity of 65%. The ability however of the CT to accurately identify sites affected by invasive disease was relatively low with the following sensitivities as relating to final histology: 32% (DI), 26% (SI), 46% (LBI), 44% (SBI), 39% (RI), 57% (PHI), 31% (MI), 63% (LNI). CONCLUSION: Pre-operative CT imaging shows high specificity but low sensitivity in detecting tumor involvement at key sites in ovarian cancer surgery. CT findings alone should not be used for surgical decision making.


Asunto(s)
Procedimientos Quirúrgicos de Citorreducción , Recurrencia Local de Neoplasia/patología , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/patología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Epitelial de Ovario , Femenino , Humanos , Ganglios Linfáticos/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/cirugía , Neoplasias Glandulares y Epiteliales/diagnóstico por imagen , Neoplasias Glandulares y Epiteliales/cirugía , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/cirugía , Recto/patología , Estudios Retrospectivos
2.
J Chem Phys ; 143(9): 094304, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26342367

RESUMEN

We report differential cross sections (DCSs) and integral cross sections (ICSs) for electron-impact vibrational-excitation of pyrimidine, at incident electron energies in the range 15-50 eV. The scattered electron angular range for the DCS measurements was 15°-90°. The measurements at the DCS-level are the first to be reported for vibrational-excitation in pyrimidine via electron impact, while for the ICS we extend the results from the only previous condensed-phase study [P. L. Levesque, M. Michaud, and L. Sanche, J. Chem. Phys. 122, 094701 (2005)], for electron energies ⩽12 eV, to higher energies. Interestingly, the trend in the magnitude of the lower energy condensed-phase ICSs is much smaller when compared to the corresponding gas phase results. As there is no evidence for the existence of any shape-resonances, in the available pyrimidine total cross sections [Baek et al., Phys. Rev. A 88, 032702 (2013); Fuss et al., ibid. 88, 042702 (2013)], between 10 and 20 eV, this mismatch in absolute magnitude between the condensed-phase and gas-phase ICSs might be indicative for collective-behaviour effects in the condensed-phase results.


Asunto(s)
Pirimidinas/química , Electrones
3.
J Chem Phys ; 143(18): 184310, 2015 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-26567665

RESUMEN

The He(i) photoelectron spectrum of furfural has been investigated, with its vibrational structure assigned for the first time. The ground and excited ionized states are assigned through ab initio calculations performed at the outer-valence Green's function level. Triple differential cross sections (TDCSs) for electron-impact ionization of the unresolved combination of the 4a″ + 21a' highest and next-highest occupied molecular orbitals have also been obtained. Experimental TDCSs are recorded in a combination of asymmetric coplanar and doubly symmetric coplanar kinematics. The experimental TDCSs are compared to theoretical calculations, obtained within a molecular 3-body distorted wave framework that employed either an orientation average or proper TDCS average. The proper average calculations suggest that they may resolve some of the discrepancies regarding the angular distributions of the TDCS, when compared to calculations employing the orbital average.

4.
J Chem Phys ; 142(19): 194302, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-26001456

RESUMEN

We report differential cross section results from an experimental investigation into the electron impact excitation of a number of the low-lying composite (unresolved) vibrational modes in phenol (C6H5OH). The measurements were carried out at incident electron energies in the range 15-40 eV and for scattered-electron angles in the range 10-90°. The energy resolution of those measurements was typically ∼80 meV. Calculations, using the GAMESS code, were also undertaken with a B3LYP/aug-cc-pVDZ level model chemistry, in order to enable us to assign vibrational modes to the features observed in our energy loss spectra. To the best of our knowledge, the present cross sections are the first to be reported for vibrational excitation of the C6H5OH molecule by electron impact.

5.
J Chem Phys ; 142(10): 104305, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25770538

RESUMEN

We report results from a joint theoretical and experimental investigation into electron scattering from the important organic species phenol (C6H5OH). Specifically, differential cross sections (DCSs) have been measured and calculated for the electron-impact excitation of the electronic states of C6H5OH. The measurements were carried out at energies in the range 15-40 eV, and for scattered-electron angles between 10° and 90°. The energy resolution of those experiments was typically ∼80 meV. Corresponding Schwinger multichannel method with pseudo-potentials calculations, with and without Born-closure, were also performed for a sub-set of the excited electronic-states that were accessed in the measurements. Those calculations were conducted at the static exchange plus polarisation (SEP)-level using a minimum orbital basis for single configuration interaction (MOBSCI) approach. Agreement between the measured and calculated DCSs was typically fair, although to obtain quantitative accord, the theory would need to incorporate even more channels into the MOBSCI.

6.
J Chem Phys ; 141(12): 124307, 2014 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-25273437

RESUMEN

We have measured (e,2e) triple differential cross sections (TDCS) for the electron-impact ionisation of phenol with coplanar asymmetrical kinematics for an incident electron energy of 250 eV. Experimental measurements of the angular distribution of the slow outgoing electrons at 20 eV are obtained when the incident electron scatters through angles of -5°, -10°, and -15°, respectively. The TDCS data are compared with calculations performed within the molecular 3-body distorted wave model. In this case, a mixed level of agreement, that was dependent on the kinematical condition being probed, was observed between the theoretical and experimental results in the binary peak region. The experimental intensity of the recoil features under all kinematical conditions was relatively small, but was still largely underestimated by the theoretical calculations.


Asunto(s)
Fenol/química , Electrones , Modelos Químicos , Estructura Molecular
7.
J Chem Phys ; 136(18): 184313, 2012 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-22583293

RESUMEN

We report on differential and integral cross section measurements for the electron impact excitation of the lowest-lying triplet electronic state (ã (3)B(1u)) in ethylene (C(2)H(4)). The energy range of the present experiments was 9 eV-50 eV, with the angular range of the differential cross section measurements being 15°-90°. As the ground electronic state of C(2)H(4) is a (1)A(g) state, this singlet → triplet excitation process is expected to be dominated by exchange scattering. The present angular distributions are found to support that assertion. Comparison, where possible, with previous experimental results from the University of Fribourg group shows very good agreement, to within the uncertainties on the measured cross sections. Agreement with the available theories, however, is generally marginal with the theories typically overestimating the magnitude of the differential cross sections. Notwithstanding that, the shapes of the theoretical angular distributions were in fact found to be in good accord with the corresponding experimental results.

8.
J Chem Phys ; 134(17): 174304, 2011 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-21548684

RESUMEN

Low energy experimental and theoretical triply differential cross sections are presented for electron impact ionization of methane (CH(4)) for both the highest occupied molecular orbital (HOMO) and next highest occupied molecular orbital (NHOMO). The HOMO is a predominantly p-type orbital which is labeled 1t(2) and the NHOMO is predominantly s-type labeled 2a(1). Coplanar symmetric (symmetric both in final state electron energies and observation angles) are presented for final state electron energies ranging from 2.5 to 20 eV. The theoretical M3DW (molecular three-body distorted wave) results are in surprisingly good agreement with experiment for the HOMO state and less satisfactory agreement for the NHOMO state. The molecular NHOMO results are also compared with the ionization of the 2s shell of neon which is the isoelectronic atom.

9.
Int Rev Neurobiol ; 160: 281-304, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34696876

RESUMEN

Alcohol is the most commonly used drug among adolescents. Their decreased sensitivity to self-regulating cues to stop drinking coincides with an enhanced vulnerability to negative outcomes of excessive drinking. In adolescents, the hippocampus is one brain region that is particularly susceptible to alcohol-induced neurodegeneration. While cell death is causal, alcohol effects on adult neurogenesis also impact hippocampal structure and function. This review describes what little is known about adolescent-specific effects of alcohol on adult neurogenesis and its relationship to hippocampal integrity. For example, alcohol intoxication inhibits neurogenesis persistently in adolescents but produces aberrant neurogenesis after alcohol dependence. Little is known, however, about the role of adolescent-born neurons in hippocampal integrity or the mechanisms of these effects. Understanding the role of neurogenesis in adolescent alcohol use and misuse is critical to our understanding of adolescent susceptibility to alcohol pathology and increased likelihood of developing alcohol problems in adulthood.


Asunto(s)
Etanol , Hipocampo , Neurogénesis , Consumo de Alcohol en Menores , Adolescente , Adulto , Etanol/toxicidad , Hipocampo/efectos de los fármacos , Hipocampo/fisiopatología , Humanos , Neurogénesis/efectos de los fármacos
10.
RSC Adv ; 11(34): 20612-20621, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35479354

RESUMEN

Experiments on neutral gas-phase nucleosides are often complicated by thermal lability. Previous mass spectrometry studies of nucleosides have identified enhanced relative production of nucleobase ions (e.g. uracil+ from uridine) as a function of desorption temperature to be the critical indicator of thermal decomposition. On this basis, the present multi-photon ionization (MPI) experiments demonstrate that laser-based thermal desorption is effective for producing uridine, 5-methyluridine, and 2'-deoxyuridine targets without thermal decomposition. Our experiments also revealed one notable thermal dependence: the relative production of the sugar ion C5H9O4 + from intact uridine increased substantially with the desorption laser power and this only occurred at MPI wavelengths below 250 nm (full range studied 222-265 nm). We argue that this effect can only be rationalized plausibly in terms of changing populations of different isomers, tautomers, or conformers in the target as a function of the thermal desorption conditions. Furthermore, the wavelength threshold behavior of this thermally-sensitive MPI channel indicates a critical dependence on neutral excited state dynamics between the absorption of the first and second photons. The experimental results are complemented by density functional theory (DFT) optimizations of the lowest-energy structure of uridine and two further conformers distinguished by different orientations of the hydroxymethyl group on the sugar part of the molecule. The energies of the transitions states between these three conformers are low compared with the energy required for decomposition.

11.
J Phys Chem A ; 113(52): 14251-4, 2009 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-19472979

RESUMEN

We report on total cross section measurements for positron scattering from dihydropyran (C(5)H(8)O), with the energy range of the present study being 0.15-48 eV. To the best of our knowledge, there are currently no other corresponding experimental data or theoretical computations against which we can compare our results. The effect of this species' important dipole moment and significant dipole polarizability on the scattering dynamics is considered, as is the opening of the positronium formation channel.

12.
Aust Dent J ; 54(2): 123-9, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19473153

RESUMEN

BACKGROUND: There have been numerous reports evaluating clinical outcomes of implants placed in institutional settings, but there are few studies relating to implants placed in private practice. The aim of this retrospective study was to analyse the clinical outcomes of 1000 consecutively placed Straumann implants in private specialist periodontal practice. METHODS: A hand-search of patient records was undertaken to identify 1000 consecutively placed implants. Data extracted included patient demographics, details of implants placed, implant sites, timing of placement after extraction, hard and soft tissue augmentation procedures, loading protocols, type of prostheses and treatment outcomes (implant survival, implant success and complications). RESULTS: The majority of implants (71.5 per cent) placed in patients aged 40 to 69, and the majority of patients (88.6 per cent) received 1 or 2 implants. During the period of the study, 9 implants were lost and 45 presented with complications requiring chairside intervention. A life table analysis showed 5 and 10-year cumulative survival rates of 99.2 per cent and 98.4 per cent respectively, and 5 and 10-year cumulative success rates of 93.1 per cent and 90.9 per cent respectively. CONCLUSIONS: With careful treatment planning and adherence to recommended surgical and prosthetic protocols, high implant survival and success rates can be achieved in a private practice setting.


Asunto(s)
Implantes Dentales/estadística & datos numéricos , Restauración Dental Permanente/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Implantación Dental Endoósea/estadística & datos numéricos , Fracaso de la Restauración Dental , Femenino , Humanos , Arcada Edéntula/rehabilitación , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Práctica Privada , Estudios Retrospectivos , Análisis de Supervivencia , Adulto Joven
13.
Neurobiol Dis ; 31(2): 218-29, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18585922

RESUMEN

Excessive alcohol intake characteristic of Alcohol Use Disorders (AUDs) produces neurodegeneration that may recover with abstinence. The mechanism of regeneration is unclear, however neurogenesis from neural stem/progenitor cells is a feasible mechanism of structural plasticity. Therefore, a timecourse of cell proliferation was examined in a rat model of an AUD and showed a striking burst in cell proliferation at 2 days of abstinence preceding the previously reported neurogenic proliferation at 7 days. New cells at 2 days, assessed by bromo-deoxy-uridine incorporation and endogenous markers, were observed throughout hippocampus and cortex. Although the majority of these new cells did not become neurons, neurogenesis was not altered at this specific time point. These new cells expressed a microglia-specific marker, Iba-1, and survived at least 2 months. This first report of microglia proliferation in a model of an AUD suggests that microgliosis could contribute to volume recovery in non-neurogenic regions during abstinence.


Asunto(s)
Trastornos del Sistema Nervioso Inducidos por Alcohol/fisiopatología , Proliferación Celular/efectos de los fármacos , Microglía/efectos de los fármacos , Degeneración Nerviosa/inducido químicamente , Regeneración Nerviosa/efectos de los fármacos , Síndrome de Abstinencia a Sustancias/fisiopatología , Alcoholismo/fisiopatología , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Encéfalo/citología , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Bromodesoxiuridina , Proteínas de Unión al Calcio/análisis , Proteínas de Unión al Calcio/metabolismo , Modelos Animales de Enfermedad , Gliosis/inducido químicamente , Gliosis/fisiopatología , Masculino , Proteínas de Microfilamentos , Microglía/fisiología , Regeneración Nerviosa/fisiología , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Ratas , Ratas Sprague-Dawley , Recuperación de la Función/fisiología , Células Madre/efectos de los fármacos , Células Madre/fisiología
14.
J Med Microbiol ; 66(6): 825-832, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28604331

RESUMEN

Purpose. Prevotella spp. represent a diverse genus of bacteria, frequently identified by both culture and molecular methods in the lungs of patients with chronic respiratory infection. However, their role in the pathogenesis of chronic lung infection is unclear; therefore, a more complete understanding of their molecular epidemiology is required.Methodology. Pulsed Field Gel Electrophoresis (PFGE) and Random Amplified Polymorphic DNA (RAPD) assays were developed and used to determine the degree of similarity between sequential isolates (n=42) from cystic fibrosis (CF) patients during periods of clinical stability and exacerbation.Results. A wide diversity of PFGE and RAPD banding patterns were observed, demonstrating considerable within-genus heterogeneity. In 8/12 (66.7 %) cases, where the same species was identified at sequential time points, pre- and post-antibiotic treatment of an exacerbation, PFGE/RAPD profiles were highly similar or identical. Congruence was observed between PFGE and RAPD (adjusted Rand coefficient, 0.200; adjusted Wallace RAPD->PFGE 0.459, PFGE->RAPD 0.128). Furthermore, some isolates could not be adequately assigned a species name on the basis of 16S rRNA analysis: these isolates had identical PFGE/RAPD profiles to Prevotella histicola.Conclusion. The similarity in PFGE and RAPD banding patterns observed in sequential CF Prevotella isolates may be indicative of the persistence of this genus in the CF lung. Further work is required to determine the clinical significance of this finding, and to more accurately distinguish differences in pathogenicity between species.

15.
Neuroscience ; 137(2): 437-45, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16289890

RESUMEN

Adolescence is a period of progressive changes in brain that likely contribute to the maturation of behavior. Human adolescents consume large amounts of ethanol. To investigate the effects of ethanol on adolescent neural progenitor cells, male rats (35-40 days old) were treated with an acute dose of ethanol (1.0, 2.5 or 5.0 g/kg, i.g.) or vehicle that resulted in peak blood levels of 33, 72, and 131 mg/dl, respectively. Bromodeoxyuridine (300 mg/kg i.p.) was administered to label dividing cells and rats were killed at 5 h to assess proliferation or at 28 days to assess cell survival and differentiation. After 5 h, bromodeoxyuridine-immunoreactivity was reduced by 63, 97 and 99% in the rostral migratory stream and 34, 71 and 99% in the subventricular zone by 1.0, 2.5 and 5.0 g/kg of ethanol respectively. In the dentate gyrus, ethanol reduced bromodeoxyuridine-immunoreactivity by 29, 40, and 78% at the three doses respectively. The density of doublecortin immunoreactivity was decreased after 3 days and the number of bromodeoxyuridine+ cells remained decreased at 28 days when most hippocampal bromodeoxyuridine+ cells coexpressed neuronal nuclei, a neuronal marker. These studies indicate that the adolescent brain is very sensitive to acute ethanol inhibition of neurogenesis.


Asunto(s)
Trastornos del Sistema Nervioso Inducidos por Alcohol/fisiopatología , Encéfalo/efectos de los fármacos , Encéfalo/crecimiento & desarrollo , Etanol/efectos adversos , Neuronas/efectos de los fármacos , Maduración Sexual/fisiología , Envejecimiento/efectos de los fármacos , Envejecimiento/fisiología , Trastornos del Sistema Nervioso Inducidos por Alcohol/patología , Alcoholismo/patología , Alcoholismo/fisiopatología , Animales , Encéfalo/fisiopatología , Recuento de Células , División Celular/efectos de los fármacos , División Celular/fisiología , Proliferación Celular/efectos de los fármacos , Depresores del Sistema Nervioso Central/efectos adversos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Proteína Doblecortina , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Masculino , Degeneración Nerviosa/inducido químicamente , Degeneración Nerviosa/patología , Degeneración Nerviosa/fisiopatología , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Ratas , Ratas Sprague-Dawley , Células Madre/efectos de los fármacos , Células Madre/fisiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-26582145

RESUMEN

Polysubstance abuse of alcohol and nicotine has been overlooked in our understanding of the neurobiology of addiction and especially in the development of novel therapeutics for its treatment. Estimates show that as many as 92% of people with alcohol use disorders also smoke tobacco. The health risks associated with both excessive alcohol consumption and tobacco smoking create an urgent biomedical need for the discovery of effective cessation treatments, as opposed to current approaches that attempt to independently treat each abused agent. The lack of treatment approaches for alcohol and nicotine abuse/dependence mirrors a similar lack of research in the neurobiology of polysubstance abuse. This review discusses three critical needs in medications development for alcohol and nicotine co-abuse: (1) the need for a better understanding of the clinical condition (i.e. alcohol and nicotine polysubstance abuse), (2) the need to better understand how these drugs interact in order to identify new targets for therapeutic development and (3) the need for animal models that better mimic this human condition. Current and emerging treatments available for the cessation of each drug and their mechanisms of action are discussed within this context followed by what is known about the pharmacological interactions of alcohol and nicotine. Much has been and will continue to be gained from studying comorbid alcohol and nicotine exposure.


Asunto(s)
Disuasivos de Alcohol/uso terapéutico , Trastornos Relacionados con Alcohol/complicaciones , Trastornos Relacionados con Alcohol/tratamiento farmacológico , Dispositivos para Dejar de Fumar Tabaco , Tabaquismo/complicaciones , Tabaquismo/tratamiento farmacológico , Disuasivos de Alcohol/farmacología , Trastornos Relacionados con Alcohol/metabolismo , Animales , Comorbilidad , Descubrimiento de Drogas , Interacciones Farmacológicas , Humanos , Tabaquismo/metabolismo
17.
Neuroscience ; 122(3): 689-98, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14622912

RESUMEN

N-methyl-D-aspartate receptor dysfunction has been strongly suggested to link with the abnormalities seen in fetal alcohol syndrome. Thus, the effects of prenatal ethanol exposure on the total expression of NR1 splice variants and the cell surface expression of both NR1 and NR2 subunits in brain were investigated in rats. Western blot studies of membrane homogenates from cerebral cortices at postnatal days 1 through 21 indicate that prenatal ethanol treatment does not alter total NR1 expression or differential expression of NR1 splice variants during development. However, immunoprecipitation studies using PSD95 suggest that both C2'-terminal variants and NR2A subunits at the cortical postsynaptic membrane of postnatal day 21 were significantly reduced after prenatal ethanol treatment. Moreover, C1-terminal variants were decreased in both pair-fed and ethanol-treated groups, while no significant differences in the levels of total NR1 subunits, NR1 splice variants containing the N- or C2-terminal cassettes, or NR2B subunits were observed. Thus, these results suggest that prenatal exposure to ethanol may influence neuronal function by selective regulation of expression of C2'-terminal variants and NR2A subunits at the cell surface.


Asunto(s)
Empalme Alternativo , Membrana Celular/metabolismo , Etanol/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal , Receptores de N-Metil-D-Aspartato/metabolismo , Envejecimiento , Animales , Animales Recién Nacidos , Peso Corporal/efectos de los fármacos , Encéfalo/citología , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Membrana Celular/genética , Femenino , Immunoblotting , Técnicas In Vitro , Masculino , Proteínas del Tejido Nervioso/metabolismo , Pruebas de Precipitina , Embarazo , Subunidades de Proteína/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/genética
18.
Behav Neurosci ; 110(2): 300-4, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8731056

RESUMEN

The N-methyl-D-aspartate (NMDA) subtype of the excitatory amino acid receptor has been implicated in several kinds of learning and memory, as well as in long-term potentiation (LTP), a putative cellular mechanism for learning and memory. This experiment examined the role of the NMDA receptor in patterned single-alternation (PSA) learning in preweanling rats following intraperitoneal injections of 0.05 mg/kg MK-801, a selective NMDA antagonist. MK-801 significantly inhibited PSA at both 60-s and 30-s intertrial intervals (ITIs), and attenuated, but did not block, learning at 8-s ITI. These results are compared with effects on PSA, a form of nonspatial, memory-based learning, observed after early postnatal exposure to alcohol, infant hippocampal lesions, and infant exposure to X-irradiation, and they add strongly to these earlier demonstrations of the role of the hippocampus in learning and memory that is clearly nonspatial and non-cognitive-map-related.


Asunto(s)
Conducta Apetitiva/fisiología , Maleato de Dizocilpina/farmacología , Hipocampo/fisiología , Potenciación a Largo Plazo/fisiología , Recuerdo Mental/fisiología , Orientación/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Animales , Animales Recién Nacidos , Conducta Apetitiva/efectos de los fármacos , Mapeo Encefálico , Antagonistas de Aminoácidos Excitadores/farmacología , Femenino , Hipocampo/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Recuerdo Mental/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Orientación/efectos de los fármacos , Ratas , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Receptores de N-Metil-D-Aspartato/efectos de los fármacos
20.
J Neurosci Methods ; 87(1): 97-103, 1999 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10065998

RESUMEN

We report the development of two mouse fibroblast-like stably-transfected cell lines (alpha1-62-4 and alpha2-B36-1) that express human alpha1 or alpha2 glycine receptor subunits, respectively. Transfected cDNAs were cloned into the pMSGneo expression vector, for which transcription is controlled by the dexamethasone-inducible MMTV promoter. Patch-clamp electrophysiological recordings revealed that the alpha1 or alpha2 glycine receptor subunits expressed in these cells form functional glycine receptors that are inhibited by strychnine and picrotoxin. Glycine activated currents in these cells with EC50s of 101+/-7 or 112+/-23 microM for cells stably expressing alpha1 or alpha2 receptors, respectively. As indicated by assays of glycine-stimulated 36Cl-- uptake, these cells express glycine receptors only after treatment with dexamethasone. In order to measure expression of the glycine alpha1 or alpha2 receptor protein, we produced a new anti-alpha1/alpha2 glycine receptor antibody (anti-alpha GR). Western blot analysis with this antibody showed a band of approximately 48 kDa only in homogenates from cells which had been transfected with the glycine alpha1 or alpha2 receptor cDNAs. Thus, through use of this stable expression system, we successfully produced cell lines expressing strychnine-sensitive glycine receptors that display similar functional characteristics to homomeric glycine receptors expressed in other systems. These stably transfected cells should provide a useful in vitro system for the study of the physiology and pharmacology of strychnine-sensitive glycine receptors.


Asunto(s)
Receptores de Glicina/biosíntesis , Animales , Western Blotting , Línea Celular , Células Cultivadas , Cloro/metabolismo , Electrofisiología , Fibroblastos , Humanos , Ratones , Técnicas de Placa-Clamp , Conejos , Transfección
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