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1.
Clin Exp Dermatol ; 43(7): 798-805, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29740850

RESUMEN

BACKGROUND: Artemisia scoparia Waldst. et Kitaib (AS) (Oriental wormwood, known as Bissuk in Korea) is a plant used in cosmetic and pharmaceutical treatments. However, the effect of AS on atopic dermatitis (AD) has not been described. AIM: To examine the inhibitory effect of AS on AD using a murine model. METHODS: We applied either AS, the butanol-extracted fraction of AS (Bu-OH) or 3,5-dicaffeoyl-epi-quinic acid (DEQA, a major component of Bu-OH) topically for 3 weeks to 2,4-dinitrofluorobenzene (DNFB)-induced skin lesions in BALB/c mice. RESULTS: AS, Bu-OH and DEQA suppressed the clinical symptoms of DNFB-induced skin lesions and he associated scratching behaviour. Numbers of inflammatory cells infiltrating skin lesions were significantly reduced by AS or Bu-OH application but not by DEQA. In addition, AS significantly suppressed serum levels of histamine and IgE, while Bu-OH significantly suppressed serum levels of histamine, IgE, thymic stromal lymphopoietin (TSLP), interleukin (IL)-4 and IL-6, and DEQA significantly suppressed serum levels of histamine, IgE, TSLP and IL-4 in DNFB-induced AD mice. In skin lesions, AS and Bu-OH significantly reduced inflammatory cytokines, whereas DEQA did not. AS, Bu-OH and DEQA all significantly suppressed caspase-1 activities. CONCLUSIONS: These results demonstrate the anti-AD effects of AS, Bu-OH and DEQA, and suggest that all three have therapeutic potential.


Asunto(s)
Artemisia , Caspasa 1/metabolismo , Ácido Clorogénico/análogos & derivados , Dermatitis Atópica/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Administración Tópica , Animales , Caspasa 1/genética , Ácido Clorogénico/uso terapéutico , Dermatitis Atópica/inducido químicamente , Dermatitis Atópica/metabolismo , Dermatitis Atópica/patología , Dinitrofluorobenceno , Modelos Animales de Enfermedad , Medicina Tradicional Coreana , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/metabolismo , Piel/patología
2.
Phys Rev Lett ; 112(24): 241101, 2014 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-24996078

RESUMEN

We report results from the BICEP2 experiment, a cosmic microwave background (CMB) polarimeter specifically designed to search for the signal of inflationary gravitational waves in the B-mode power spectrum around ℓ∼80. The telescope comprised a 26 cm aperture all-cold refracting optical system equipped with a focal plane of 512 antenna coupled transition edge sensor 150 GHz bolometers each with temperature sensitivity of ≈300 µK(CMB)√s. BICEP2 observed from the South Pole for three seasons from 2010 to 2012. A low-foreground region of sky with an effective area of 380 square deg was observed to a depth of 87 nK deg in Stokes Q and U. In this paper we describe the observations, data reduction, maps, simulations, and results. We find an excess of B-mode power over the base lensed-ΛCDM expectation in the range 30 < ℓ < 150, inconsistent with the null hypothesis at a significance of >5σ. Through jackknife tests and simulations based on detailed calibration measurements we show that systematic contamination is much smaller than the observed excess. Cross correlating against WMAP 23 GHz maps we find that Galactic synchrotron makes a negligible contribution to the observed signal. We also examine a number of available models of polarized dust emission and find that at their default parameter values they predict power ∼(5-10)× smaller than the observed excess signal (with no significant cross-correlation with our maps). However, these models are not sufficiently constrained by external public data to exclude the possibility of dust emission bright enough to explain the entire excess signal. Cross correlating BICEP2 against 100 GHz maps from the BICEP1 experiment, the excess signal is confirmed with 3σ significance and its spectral index is found to be consistent with that of the CMB, disfavoring dust at 1.7σ. The observed B-mode power spectrum is well fit by a lensed-ΛCDM+tensor theoretical model with tensor-to-scalar ratio r = 0.20_(-0.05)(+0.07), with r = 0 disfavored at 7.0σ. Accounting for the contribution of foreground, dust will shift this value downward by an amount which will be better constrained with upcoming data sets.

3.
Cell Death Differ ; 14(8): 1518-28, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17541429

RESUMEN

Gemin5 is a 170-kDa WD-repeat-containing protein that was initially identified as a component of the survival of motor neurons (SMN) complex. We now show that Gemin5 facilitates the activation of apoptosis signal-regulating kinase 1 (ASK1) and downstream signaling. Gemin5 physically interacted with ASK1 as well as with the downstream kinases SEK1 and c-Jun NH(2)-terminal kinase (JNK1), and it potentiated the H(2)O(2)-induced activation of each of these kinases in intact cells. Moreover, Gemin5 promoted the binding of ASK1 to SEK1 and to JNK1, as well as the ASK1-induced activation of JNK1. In comparison, Gemin5 did not physically associate with MKK7, MKK3, MKK6, or p38. Furthermore, depletion of endogenous Gemin5 by RNA interference (RNAi) revealed that Gemin5 contributes to the activation of ASK1 and JNK1, and to apoptosis induced by H(2)O(2) and tumor necrosis factor-alpha (TNFalpha) in HeLa cells. Together, our results suggest that Gemin5 functions as a scaffold protein for the ASK1-JNK1 signaling module and thereby potentiates ASK1-mediated signaling events.


Asunto(s)
MAP Quinasa Quinasa Quinasa 5/metabolismo , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Ribonucleoproteínas Nucleares Pequeñas/metabolismo , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Secuencia de Bases , Línea Celular , ADN Complementario/genética , Células HeLa , Humanos , Peróxido de Hidrógeno/farmacología , Técnicas In Vitro , MAP Quinasa Quinasa Quinasa 5/genética , Proteína Quinasa 8 Activada por Mitógenos/genética , Unión Proteica , ARN Interferente Pequeño/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ribonucleoproteínas Nucleares Pequeñas/antagonistas & inhibidores , Ribonucleoproteínas Nucleares Pequeñas/genética , Proteínas del Complejo SMN , Transducción de Señal , Transfección , Factor de Necrosis Tumoral alfa/farmacología
4.
Clin Neuroradiol ; 25(4): 415-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25373351

RESUMEN

Central nervous system (CNS) involvement of scrub typhus infection is well known. Most CNS involvement of scrub typhus infection present as meningitis or encephalitis. We report on a patient suffering from hemorrhagic transformation of intracranial lesions caused by Orientia tsutsugamushi. A 53-year-old female farmer who was infected by scrub typhus was treated with doxycycline and recovered from the systemic illness. However, headache persisted. Brain radiologic studies revealed acute intracranial hemorrhage and enhancing lesion, which implied a CNS involvement. Hemorrhagic transformation of encephalitis by scrub typhus is very rare complication and to our best knowledge, this is the first report of hemorrhagic transformation of scrub typhus encephalitis. Clinician should consider the possibility of hemorrhagic transformation of encephalitis in cases of scrub typhus infection.


Asunto(s)
Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/etiología , Encefalitis Infecciosa/complicaciones , Encefalitis Infecciosa/diagnóstico , Tifus por Ácaros/complicaciones , Tifus por Ácaros/diagnóstico , Hemorragia Cerebral/terapia , Diagnóstico Diferencial , Resultado Fatal , Femenino , Humanos , Encefalitis Infecciosa/terapia , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Enfermedades Raras/diagnóstico , Enfermedades Raras/etiología , Enfermedades Raras/terapia , Tifus por Ácaros/terapia , Tomografía Computarizada por Rayos X/métodos
5.
Neuroscience ; 67(2): 293-300, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7675170

RESUMEN

The nicotinic antagonists d-tubocurarine and trimethaphan camsylate competitively inhibit GABA-induced currents. Hexamethonium, mecamylamine and dihydro-beta-erythroidine, other nicotinic antagonists, do not affect GABA-elicited currents. The trimethaphan effect is completely reversed by a putative convulsant receptor antagonist, alpha-isopropyl-alpha-methyl-gamma-butyrolactone, which implies that the trimethaphan binding site may be closely associated with the convulsant site. However, nicotine was ineffective in competing for either the d-tubocurarine or trimethaphan effect at the GABAA receptor. From these observations, we propose that the nicotinic and GABAA receptor ionophore complexes share similar configurational patterns that accommodate some of the same molecules. Possible mechanisms for the trimethaphan and d-tubocurarine blockades are discussed.


Asunto(s)
Antagonistas del GABA/farmacología , Hipocampo/metabolismo , Neuronas/metabolismo , Antagonistas Nicotínicos/farmacología , Ácido gamma-Aminobutírico/farmacología , Animales , Células Cultivadas , Electrofisiología , Antagonistas de Receptores de GABA-A , Hipocampo/citología , Hipocampo/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Conformación Molecular , Neuronas/efectos de los fármacos , Agonistas Nicotínicos/farmacología , Técnicas de Placa-Clamp , Ratas , Ratas Sprague-Dawley
6.
Neuroscience ; 87(4): 807-15, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9759968

RESUMEN

The effect of picrotoxinin on glycine-induced chloride currents was studied in dissociated rat hippocampal neuron culture in whole-cell and excised outside-out patches. Picrotoxinin blocked the glycine induced chloride currents. The picrotoxinin effect at 20 microM on glycine dose response relationship suggested a competitive mechanism. However, at 1 mM, the picrotoxinin effect was largely noncompetitive. In excised patches, glycine activated two types of channels distinguished by a difference in conductances. The first group had single channel conductances of around 47 pS and another around 100 pS. Occasionally, both types of channels were found in the same excised patch. Low concentration of picrotoxinin selectively blocked large conductance channels. At higher concentrations of 0.5 to 1 mM, picrotoxinin blocked the small conductance channels by a flickering block. These findings indicate that the whole-cell glycine current in rat hippocampal neurons is mediated by at least two types of channels. The two types of channels have distinct conductance, picrotoxinin sensitivity and different mechanism of picrotoxinin block.


Asunto(s)
Canales de Cloruro/antagonistas & inhibidores , Cloruros/metabolismo , Antagonistas del GABA/farmacología , Hipocampo/citología , Proteínas del Tejido Nervioso/efectos de los fármacos , Neuronas/efectos de los fármacos , Picrotoxina/análogos & derivados , Receptores de Glicina/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Animales , Canales de Cloruro/química , Hipocampo/efectos de los fármacos , Transporte Iónico/efectos de los fármacos , Ionóforos/farmacología , Proteínas del Tejido Nervioso/metabolismo , Técnicas de Placa-Clamp , Picrotoxina/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Glicina/metabolismo , Sesterterpenos
7.
Neuroscience ; 59(3): 689-98, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8008213

RESUMEN

Whole-cell patch clamp recordings were performed in embryonic chick brain slices to characterize responses to nicotinic receptor activation in the mesencephalic lateral spiriform nucleus. Using intracellular recording, we previously reported the presence of functional high-affinity nicotinic sites in this nucleus that are insensitive to blockade with kappa- and alpha-bungarotoxin. We now report that nicotinic agonists not only produce an inward current in these cells, but also elicit a massive increase in the frequency of spontaneous postsynaptic currents without changing the amplitude distribution or risetime and decay kinetics of these events. The nicotinic receptor antagonist, dihydro-beta-erythroidine, blocks both the postsynaptic inward current and the enhancement of spontaneous postsynaptic currents. The spontaneous currents reverse at or near the chloride ion equilibrium potential and are completely blocked by 10 microM bicuculline, indicating that these events are likely to be GABAergic inhibitory postsynaptic currents. The nicotinic agonist-induced enhancement in inhibitory postsynaptic current frequency is blocked by 1.0 microM tetrodotoxin, demonstrating that the effect is mediated through the activation of voltage-dependent sodium channels. Nicotinic receptors are widely distributed in the central nervous system and in some cases are thought to modulate the release of various neurotransmitters. Our results show that activation of nicotinic receptors facilitates inhibitory neurotransmission in the avian lateral spiriform nucleus by increasing the frequency of spontaneous GABAergic postsynaptic currents. These data support a role for nicotinic receptors in the regulation of GABA release from nerve terminals in this nucleus.


Asunto(s)
Bicuculina/farmacología , Dihidro-beta-Eritroidina/farmacología , Mesencéfalo/fisiología , Neuronas/fisiología , Nicotina/farmacología , Receptores Nicotínicos/fisiología , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/fisiología , Animales , Bungarotoxinas/farmacología , Carbacol/farmacología , Embrión de Pollo , Yoduro de Dimetilfenilpiperazina/farmacología , Potenciales Evocados/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Neuronas/efectos de los fármacos , Antagonistas Nicotínicos , Bloqueadores de los Canales de Sodio , Canales de Sodio/fisiología , Transmisión Sináptica/efectos de los fármacos , Tetrodotoxina/farmacología
8.
Neuroscience ; 79(4): 999-1004, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9219962

RESUMEN

A model of in vitro traumatic injury with dissociated rat hippocampal neurons was studied to explore the mechanism of cell death. The neurotoxicity induced by traumatic injury to the cell culture can be transferred to a naive uninjured culture by media exchange. This toxicity is attenuated by dimethylsulfoxide or superoxide dismutase, suggesting that this toxicity is mediated by a free radical generation. Ionotropic glutamate receptor antagonists had no effect. This toxicity was effectively blocked by the pretreatment of the naive uninjured recipient cultures with cycloheximide or with actinomycin D. The DNA fragmentation could be illustrated with in situ nick translation in the cells which seem to have lost their cytoplasm. The nuclear morphology of neurons labeled by a neurofilament-specific antibody, SMI-31, demonstrated chromatin condensation and nucleosome formation. Traumatic injury induces release of an unknown toxin into the extracellular space. These observations suggest that a traumatized neuronal culture can propagate cell death of naive uninjured cells by releasing a neurotoxin that causes apoptosis.


Asunto(s)
Apoptosis/fisiología , Lesiones Encefálicas/patología , Hipocampo/patología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Ratas , Ratas Sprague-Dawley , Heridas y Lesiones/patología
9.
J Neurotrauma ; 15(2): 141-7, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9512089

RESUMEN

Indirect glutamate toxicity can be demonstrated by exposing dissociated rat hippocampal cultures to the media of the same culture transiently exposed (1 min) to glutamate (0.5 mM). The toxicity was maximum when the media was collected 5 min after the glutamate exposure. While the primary glutamate toxicity was attenuated by ionotropic glutamate receptor antagonists, the transferred, indirect toxicity was unaffected by the same antagonists. The changes in nuclear morphology indicated chromatin condensation and nuclear fragmentation in both primary and transferred toxicity. The stain for DNA damage by TUNEL method also revealed cells staining positive in both primary and transferred glutamate toxicity. These observations demonstrate that glutamate-induced neurotoxicity can be propagated to the uninjured cells by an unknown toxin released into the extracellular space. This neurotoxin induced both apoptosis and necrosis in cultured rat hippocampal cells.


Asunto(s)
Ácido Glutámico/envenenamiento , Hipocampo/efectos de los fármacos , 6-Ciano 7-nitroquinoxalina 2,3-diona/farmacología , Animales , Apoptosis/efectos de los fármacos , Muerte Celular/fisiología , Técnicas de Cultivo , Fragmentación del ADN , Maleato de Dizocilpina/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Hipocampo/patología , Hipocampo/fisiopatología , Necrosis , Neuroglía/efectos de los fármacos , Neuroglía/patología , Fármacos Neuroprotectores/farmacología , Ratas , Ratas Sprague-Dawley
10.
Brain Res ; 669(2): 320-4, 1995 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-7712189

RESUMEN

In dissociated rat hippocampal neurons, slow bath application (1 ml/min) of glutamate (50 microM) increased both excitatory and inhibitory synaptic activities. This glutamate effect was abolished by tetrodotoxin or cadmium. The constant perfusion (1 h) of glutamate 50 microM was toxic to the neurons. This toxicity was also blocked by TTX. This suggests that unlike the excitotoxicity at a high (mM) concentration, the glutamate toxicity at 50 microM is mediated by its effect on synaptic transmission.


Asunto(s)
Ácido Glutámico/farmacología , Hipocampo/fisiología , Neuronas/fisiología , Transmisión Sináptica/fisiología , 6-Ciano 7-nitroquinoxalina 2,3-diona/farmacología , Animales , Potenciales de la Membrana , Ratas , Tetrodotoxina/farmacología
11.
Brain Res ; 857(1-2): 41-55, 2000 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-10700551

RESUMEN

The distribution of labeled neurons in the brain and spinal cord was studied after injecting the Bartha strain of pseudorabies virus (PRV) into the sciatic nerve to provide a baseline for studying neural circuitry after spinal cord injury (SCI) and regeneration. Following a single injection of viral particles into the left sciatic nerve, PRV labeling was found in the spinal cord at 2 days post-injection (p.i.). Increasing complexity in viral labeling from the spinal cord to supraspinal regions became apparent with increasing survival time. In brain regions, several neuronal groups that regulate sympathetic outflow, such as the rostroventrolateral medulla, the lateral paragigantocellular nuclei, and the A5 cells, were densely labeled. However, relatively sparse labeling was noticed in the lateral vestibular nuclei, the red nucleus and the motor cortex whose spinal projections regulate somatic motor function, although those areas were abundantly labeled with Fast blue (FB) in a double-labeling experiment in which FB was co-injected into the lumbar cord. The pattern of viral labeling became more complex beyond 5 days p.i. when increased numbers of cell groups were labeled with PRV but not FB. In addition, some infected neurons started to lyse, as evidenced by a decrease in viral labeling at 7 days p.i. Thus, the 5th day post-viral injection would appear to be an appropriate survival time to obtain maximal labeling with acceptable specificity. We suggest that transneuronal labeling using PRV should be appropriate for studying multi-neural circuitry after SCI and regeneration.


Asunto(s)
Transporte Axonal/fisiología , Comunicación Celular/fisiología , Sistema Nervioso Central/citología , Herpesvirus Suido 1/inmunología , Vías Nerviosas/citología , Neuronas/citología , Nervio Ciático/citología , Amidinas , Animales , Recuento de Células , Diencéfalo/citología , Femenino , Colorantes Fluorescentes , Inmunohistoquímica , Bulbo Raquídeo/citología , Mesencéfalo/citología , Neuronas/virología , Puente/citología , Ratas , Ratas Endogámicas F344 , Rizotomía , Raíces Nerviosas Espinales/cirugía , Telencéfalo/citología , Factores de Tiempo
12.
Eur J Pharmacol ; 141(3): 395-9, 1987 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-3666033

RESUMEN

The effect of intravenous (i.v.) nicotine on the single unit activity of midbrain dopamine (DA) neurons was studied in rats under either local or general anesthesia. Nicotine (50-500 micrograms/kg) produced a dose-related increase in the firing rate of nigral pars compacta DA cells (A9), up to 25% above baseline, irrespective of the preparation. The same range of doses was more than three times as effective on ventral tegmental area DA cells (A10) in rats paralyzed and given a local anesthetic. By contrast, the majority of these cells were temporarily depressed in deeply anesthetized animals. All of the above effects were reversed and prevented by i.v. mecamylamine suggesting the involvement of nicotine cholinergic receptors. Moreover, after nicotine-induced stimulation, low doses of i.v. apomorphine inhibited the firing rate similar to controls indicating that dopamine receptors are not directly involved in the nicotinic action. The results suggest that acute nicotine shares with other drugs of abuse the characteristic of being more effective in stimulating A10 than A9 neurons.


Asunto(s)
Dopamina/fisiología , Neuronas/efectos de los fármacos , Nicotina/farmacología , Tegmento Mesencefálico/fisiología , Potenciales de Acción/efectos de los fármacos , Anestesia , Animales , Apomorfina/farmacología , Masculino , Mecamilamina/farmacología , Ratas , Ratas Endogámicas , Estimulación Química , Tegmento Mesencefálico/efectos de los fármacos
13.
Neurosci Lett ; 178(2): 260-2, 1994 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-7824206

RESUMEN

A brief exposure of dissociated hippocampal culture to aluminum (AlCl3, 60 min) is toxic to neurons. The aluminum toxicity is independent of calcium or glutamate receptor activation. However, at a high concentration (1 mM), aluminum seems to have a protective effect.


Asunto(s)
Aluminio/envenenamiento , Hipocampo/efectos de los fármacos , Neuronas/efectos de los fármacos , Aluminio/administración & dosificación , Aluminio/farmacología , Animales , Calcio/metabolismo , Muerte Celular , Células Cultivadas , Maleato de Dizocilpina/farmacología , Relación Dosis-Respuesta a Droga , Espacio Extracelular/metabolismo , Hipocampo/patología , Fármacos Neuroprotectores/farmacología , Cianuro de Potasio/envenenamiento , Ratas , Factores de Tiempo
14.
Neurosurgery ; 42(4): 843-9, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9574649

RESUMEN

OBJECTIVE: Hyperthermia has been clinically applied to some types of brain tumors. However, the detailed mechanisms of this growth inhibition are not clear. The effect of mild hyperthermia on cultured human glioblastoma cell line, A172, was studied. METHODS: A172 cells were heat treated (43-44.5 degrees C) for 1 hour in the growing phase. Cell viability was assessed by trypan blue dye exclusion assay. The presence of apoptosis was determined by the morphological changes observed using phase contrast microscopy and nuclear changes observed using HOECHST 33342 stain. For the evaluation of cellular deoxyribonucleic acid fragmentation, the TUNEL method was used. The expression of p53 and bax proteins was evaluated by Western blot, and the bax messenger ribonucleic acid was detected by Northern blot. RESULTS: Heat treatment induced cell death in time- and temperature-dependent manners. The nuclear staining with HOECHST 33342 demonstrated morphological changes consistent with apoptosis. The TUNEL stain also demonstrated damages in the deoxyribonucleic acid. These morphological changes were accompanied by the accumulation of p53 protein, bax protein, and messenger ribonucleic acid. CONCLUSION: These results indicate that mild hyperthermia induces apoptosis in A172 glioblastoma cells.


Asunto(s)
Apoptosis/fisiología , Glioblastoma/fisiopatología , Calor , Proteínas Proto-Oncogénicas c-bcl-2 , Bencimidazoles , Supervivencia Celular/fisiología , Fragmentación del ADN , Colorantes Fluorescentes , Glioblastoma/patología , Proteínas del Choque Térmico HSP72 , Proteínas de Choque Térmico/metabolismo , Humanos , Microscopía de Contraste de Fase , Inhibidores de la Síntesis de la Proteína/farmacología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , ARN/biosíntesis , ARN Mensajero/metabolismo , Células Tumorales Cultivadas/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína X Asociada a bcl-2
15.
Neurosurgery ; 24(5): 749-53, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2716985

RESUMEN

The availability of transcranial Doppler sonography has resulted in an easy, noninvasive, reproducible, and highly reliable method for evaluating the flow characteristics of carotid-cavernous sinus fistulas. It also allows the follow-up of the effect of different interventional measures, specifically, embolization with detachable balloons. An illustrative case is reported, in which the findings of serial transcranial Doppler sonograms are correlated with findings on computed tomographic scans and angiograms. The impact of our findings on future approaches to the hemodynamic classification of these acquired vascular shunts is discussed.


Asunto(s)
Fístula Arteriovenosa/fisiopatología , Arterias Carótidas/fisiopatología , Seno Cavernoso/fisiopatología , Hemodinámica , Ultrasonido , Anciano , Fístula Arteriovenosa/diagnóstico por imagen , Velocidad del Flujo Sanguíneo , Arterias Carótidas/diagnóstico por imagen , Seno Cavernoso/diagnóstico por imagen , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Tomografía Computarizada por Rayos X
16.
Neurosurgery ; 36(5): 1003-7; discussion 1007-8, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7791963

RESUMEN

In a rat hippocampal cell culture, we studied the mechanism of adenosine-mediated neuroprotection in traumatic injury to neurons. When the processes and bodies of cells in culture were mechanically disrupted, neurons that were located at a distance from the damage site died. This secondary neuronal death is at least partially mediated by glutamate, because MK801, a specific N-methyl-D-aspartate glutamate channel blocker, diminished the toxic effect. Furthermore, cyclopentyl adenosine, a specific A1 adenosine receptor agonist that specifically attenuates synaptic release at the excitatory terminal, also blocked this trauma-mediated cell death. The dissemination of neurotoxicity from cell injury implies a release of a toxin by the dying cells. Consistent with this hypothesis, we found that neurotoxicity could be transferred to an uninjured neuronal culture by applying extracellular solution of the damaged culture to the healthy undamaged culture, as long as the fluid was transferred within 5 minutes. However, the glutamate concentrations in this medium were never higher than 20 nmol/L, suggesting that glutamate is not mediating the soluble and transferable toxicity. Consistent with this observation, the transferable neurotoxicity was not blocked by MK801 but was effectively blocked by cyclopentyl adenosine. Our observations suggest that traumatic cell death in culture is mediated by multiple mechanisms, including glutamate excitotoxicity.


Asunto(s)
Adenosina/agonistas , Muerte Celular , Hipocampo/citología , Hipocampo/efectos de los fármacos , Animales , Lesiones Encefálicas/patología , Muerte Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo/farmacología , Maleato de Dizocilpina/farmacología , Espacio Extracelular/fisiología , Ratas , Ratas Sprague-Dawley , Teofilina/análogos & derivados , Teofilina/farmacología
17.
J Neurosurg ; 66(1): 72-9, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3783261

RESUMEN

A case of craniopagus twins joined in the temporoparietal area is presented, along with a review of the literature on craniopagus. A large area of brain was shared between the neurologically normal infants, with defects in the scalp, skull, and dura. The twins were separated in a three-step procedure. First, areas of shared brain were divided and separated with silicone sheets. The second procedure consisted of the insertion of scalp expanders to allow primary skin closure. In the third procedure complete separation was performed which was complicated by severe hypotension in one infant that was due to dural sinus hemorrhage. Cerebrospinal fluid leak was the most difficult problem encountered in the postoperative period; this was treated with lumboperitoneal and ventriculoperitoneal shunts. After 2 years, one twin is neurologically normal; the other is severely developmentally delayed, possibly related to the severe hypotension experienced during the third procedure. A review of the literature on craniopagus is presented. Analysis of data in the literature suggests that the area involved in the craniopagus as well as the venous connections are closely related to survival following separation of craniopagus twins.


Asunto(s)
Encéfalo/anomalías , Duramadre/anomalías , Gemelos Siameses/cirugía , Encéfalo/cirugía , Derivaciones del Líquido Cefalorraquídeo , Duramadre/cirugía , Humanos , Hipotensión/etiología , Recién Nacido , Masculino , Complicaciones Posoperatorias , Tomografía Computarizada por Rayos X , Gemelos Siameses/fisiopatología
18.
J Neurosurg ; 79(1): 111-5, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8315447

RESUMEN

Glutamate has been shown to play an important role in delayed neuronal cell death occurring due to ischemia. Attenuation of synaptically released glutamate can be accomplished by modulators such as adenosine and baclofen. This study focused on the ability of adenosine to attenuate the excitotoxicity secondary to glutamate receptor activation in vitro after exposure to potassium cyanide (KCN) in hippocampal neuronal cell cultures. For this study, hippocampal cell cultures were obtained from 1-day-old rats and trypan blue staining was used for assessment of cell viability. It was found that the N-methyl-D-aspartate-specific antagonist MK801 (10 microM) attenuated neuronal cell death resulting from exposure to 1 mM KCN for 60 minutes. Adenosine (10 to 1000 microM) decreased neuronal cell death secondary to the same concentration of KCN in a dose-dependent manner. This same neuroprotective effect is mimicked by the adenosine A1-specific receptor agonist N6-cyclopentyladenosine (10 microM). The A1-specific receptor antagonist 8-cyclopentyl-1,3-dimethylxanthine (10 to 1000 nM) blocked the neuroprotective effect of adenosine in a dose-dependent manner. Therefore, neuronal cell death produced by KCN in the experimental model described was mediated at least in part by glutamate. This neuronal cell death was attenuated by adenosine via the A1-specific mechanism.


Asunto(s)
Adenosina/farmacología , Neuronas/efectos de los fármacos , Cianuro de Potasio/farmacología , Adenosina/análogos & derivados , Animales , Muerte Celular/efectos de los fármacos , Células Cultivadas , Maleato de Dizocilpina/farmacología , Hipocampo/citología , Concentración Osmolar , Cianuro de Potasio/antagonistas & inhibidores , Antagonistas Purinérgicos , Teobromina/análogos & derivados , Teobromina/farmacología , Teofilina/análogos & derivados , Teofilina/farmacología
19.
J Infect ; 46(4): 253-5, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12799155

RESUMEN

We report a case of patient with Clostridium perfringens septicemia and thrombophlebitis of the portal vein (pylephlebitis), probably secondary to an initially unrecognized gastric ulcer. The extension of the thrombosis from the superior mesenteric vein to the main portal vein on a repeat CT scan and subsequent partial resolution of the thrombus with antibiotic therapy alone, suggested that Clostridium perfringens bacteremia may have enhanced the formation of thrombus. The coexistence of Clostridium perfringens septicemia and pylephlebitis should prompt a search for intra-abdominal processes as the portal of entry of infection.


Asunto(s)
Infecciones por Clostridium/complicaciones , Clostridium perfringens/aislamiento & purificación , Sepsis/microbiología , Tromboflebitis/complicaciones , Anciano , Humanos , Masculino , Vena Porta , Tromboflebitis/etiología
20.
Reprod Fertil Dev ; 12(3-4): 133-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11302422

RESUMEN

The development of porcine oocytes from large (3.1-8.0 mm in diameter) or small (<3.1 mm) follicles was examined after maturation culture in medium containing porcine follicular fluid (pFF). Large follicles yielded larger (256 microm v. 221 microm; P<0.05) cumulus-oocyte complexes and more (22 v. 14%) morphologically normal oocytes than small follicles (Experiment 1). In Experiments 2-4, maturation media supplemented with mixed pFF (10%) from small and large follicles was used. More oocytes from large follicles matured (58% v. 91%), formed pronuclei (81% v. 90%) and developed to the blastocyst stage (2% v. 10%) than oocytes from small follicles. In Experiments 5-7, the effects of pFF collected from either small or large follicles on oocyte development were examined. Regardless of the source of oocytes, large-follicle-derived pFF more significantly enhanced preimplantation development than did small-follicle-derived pFF. The highest rate of blastocyst formation (16%) was found when oocytes from large follicles were cultured in maturation medium containing large-follicle-derived pFF. These results suggest that oocytes from large follicles have greater developmental potential than oocytes from small follicles, and that the origin of pFF, which is added to the maturation media, might be an important factor for improving in vitro development of porcine oocytes.


Asunto(s)
Oocitos/crecimiento & desarrollo , Folículo Ovárico/citología , Folículo Ovárico/fisiología , Animales , Medios de Cultivo , Femenino , Líquido Folicular/fisiología , Técnicas In Vitro , Porcinos
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