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1.
Female Pelvic Med Reconstr Surg ; 27(1): 39-45, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31008776

RESUMEN

OBJECTIVES: To assess impact of a decision aid video in Latina patients with symptomatic pelvic organ prolapse (POP) on knowledge, satisfaction and decisional conflict related to initial treatment selection. METHODS: Pilot study with randomized prospective design. Thirty Latina women with symptomatic POP were randomized to a decision aid intervention plus standard care (N = 15) or standard care alone (N = 15) group. Decision aid intervention consisted of a 10-minute video presented at time of initial evaluation for POP. Outcome measures included the Prolapse and Incontinence Knowledge Quiz ("Knowledge"), the Satisfaction with Decision ("Satisfaction") and Decisional Conflict (DCS) scales, and were assessed at 4 different timepoints: after initial visit, and at 1, 3 and 6 months after. Data was analyzed using repeated-measures ANOVA and pairwise between-group comparisons. RESULTS: Demographic and baseline data were similar between groups. There was a significant interaction between groups and time on the Knowledge scores (P = 0.03). Knowledge scores were higher at the initial visit in the intervention group (10.6 ± 0.8 vs 9.53 ± 1.4, P = 0.014). Satisfaction scores were lower in the intervention group on longitudinal analysis, indicating higher satisfaction (P = 0.02). There was no difference on overall Decisional Conflict scores between groups. The intervention group had lower scores on the "effective decision" DCS subscale at 3 and 6 months and "informed" DCS subscale at 3 months. CONCLUSIONS: A decision aid video intervention in Latina women with POP used at the time of initial evaluation may help the patient make a more informed treatment decision by increasing condition-related knowledge and lead to greater long-term satisfaction.


Asunto(s)
Toma de Decisiones , Técnicas de Apoyo para la Decisión , Prolapso de Órgano Pélvico/terapia , Grabación en Video , Anciano , Femenino , Hispánicos o Latinos , Humanos , Persona de Mediana Edad , Prolapso de Órgano Pélvico/diagnóstico , Proyectos Piloto , Estudios Prospectivos , Autoinforme
2.
J Neurosci Methods ; 308: 197-204, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30107206

RESUMEN

BACKGROUND: Neosaxitoxin (NeoSTX) and related paralytics shellfish toxins has been successfully used as local anesthetic and muscle relaxants to treat a variety of ailments. The primary mechanism of action of these toxins occurs by blocking voltage-gated sodium channels with compounds such as TTX, lidocaine, or derivatives. However, most of these non-classical sodium channel blockers act with a reduced time effect as well as ensuing neurotoxicity. NEW METHOD: In this report, we show that the use of local NeoSTX injections inactivates the hippocampal neuronal activity reversibly with a by long-term dynamics, without neuronal damage. RESULTS: A single 10 ng/µl injection of NeoSTX in the dorsal CA1 region abolished for up to 48 h memory capacities and neuronal activity measured by the neuronal marker c-fos. After 72 h of toxin injection, the animals fully recover their memory capacities and hippocampal neuronal activity. The histological inspection of NeoSTX injected brain regions revealed no damage to the tissue or reactive gliosis, similar to vehicle injection. Acute electrophysiological recording in vivo shows, also, minimal spreading of the NeoSTX in the cerebral tissue. COMPARISON WITH EXISTING METHODS: Intracerebral NeoSTX injection showed longer effects than other voltage sodium channel blocker, with minimal spreading and no neuronal damage. CONCLUSION: NeoSTX is a new useful tool that reversibly inactivates different brains region for a long time, with minimal diffusion and without neuronal damage. Moreover, NeoSTX can be used as a valuable sodium channel blocker for many studies in vivo and with potential therapeutic uses.


Asunto(s)
Región CA1 Hipocampal/efectos de los fármacos , Neuronas/efectos de los fármacos , Saxitoxina/análogos & derivados , Bloqueadores de los Canales de Sodio/administración & dosificación , Memoria Espacial/efectos de los fármacos , Amnesia/inducido químicamente , Animales , Región CA1 Hipocampal/fisiología , Masculino , Neuronas/fisiología , Ratas Sprague-Dawley , Reconocimiento en Psicología/efectos de los fármacos , Saxitoxina/administración & dosificación
3.
Nat Commun ; 9(1): 1035, 2018 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-29515124

RESUMEN

"The technical support from SLAC Accelerator Directorate, Technology Innovation Directorate, LCLS laser division and Test Facility Division is gratefully acknowledged. We thank S.P. Weathersby, R.K. Jobe, D. McCormick, A. Mitra, S. Carron and J. Corbett for their invaluable help and technical assistance. Research at SLAC was supported through the SIMES Institute which like the LCLS and SSRL user facilities is funded by the Office of Basic Energy Sciences of the U.S. Department of Energy under Contract No. DE-AC02-76SF00515. The UED work was performed at SLAC MeV-UED, which is supported in part by the DOE BES SUF Division Accelerator & Detector R&D program, the LCLS Facility, and SLAC under contract Nos. DE-AC02-05-CH11231 and DE-AC02-76SF00515. Use of the Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515."and"Work at BNL was supported by DOE BES Materials Science and Engineering Division under Contract No: DE-AC02-98CH10886. J.C. would like to acknowledge the support from National Science Foundation Grant No. 1207252. E.E.F. would like to acknowledge support from the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES) under Award No. DE-SC0003678."This has been corrected in both the PDF and HTML versions of the Article.

4.
Nat Commun ; 9(1): 388, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29374151

RESUMEN

Magnetostriction, the strain induced by a change in magnetization, is a universal effect in magnetic materials. Owing to the difficulty in unraveling its microscopic origin, it has been largely treated phenomenologically. Here, we show how the source of magnetostriction-the underlying magnetoelastic stress-can be separated in the time domain, opening the door for an atomistic understanding. X-ray and electron diffraction are used to separate the sub-picosecond spin and lattice responses of FePt nanoparticles. Following excitation with a 50-fs laser pulse, time-resolved X-ray diffraction demonstrates that magnetic order is lost within the nanoparticles with a time constant of 146 fs. Ultrafast electron diffraction reveals that this demagnetization is followed by an anisotropic, three-dimensional lattice motion. Analysis of the size, speed, and symmetry of the lattice motion, together with ab initio calculations accounting for the stresses due to electrons and phonons, allow us to reveal the magnetoelastic stress generated by demagnetization.

5.
Biol Reprod ; 96(1): 81-92, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28395337

RESUMEN

Although the positive effects of vaginal estrogens and the selective estrogen receptor modulator, ospemifene (OS), on the vaginal epithelium are well recognized, less is known regarding the effects of these therapies on the lower urinary tract or vaginal muscularis. Clinical evidence suggests that vaginally administered estrogen may improve overactive bladder-related symptoms. The objective of this study was to compare the effects of OS, vaginal conjugated equine estrogens (CEE), or both on the vaginal wall and lower urinary tract in a rat model of menopause. Contractile force of the bladder neck, dome, and external urethral sphincter at optimal field stimulation did not differ significantly among treatment groups. Pharmacologic responses to atropine, carbachol, and potassium chloride were similar among groups. Vaginal epithelial thickness and differentiation were differentially regulated by CEE or OS. Ospemifene altered epithelial differentiation pathways in vaginal epithelium in a unique way, and these effects were additive with local CEE. Unless contraindicated, the beneficial effects of vaginal CEE on the vaginal wall outweigh those of OS.


Asunto(s)
Estrógenos Conjugados (USP)/uso terapéutico , Estrógenos/uso terapéutico , Tamoxifeno/análogos & derivados , Uretra/efectos de los fármacos , Vejiga Urinaria/efectos de los fármacos , Vagina/efectos de los fármacos , Administración Intravaginal , Administración Oral , Animales , Evaluación Preclínica de Medicamentos , Estrógenos/farmacología , Estrógenos Conjugados (USP)/farmacología , Femenino , Menopausia , Distribución Aleatoria , Ratas Sprague-Dawley , Tamoxifeno/farmacología , Tamoxifeno/uso terapéutico
7.
Exp Mol Pathol ; 99(3): 702-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26546836

RESUMEN

BACKGROUND: Human papillomavirus (HPV) is a highly prevalent sexually transmitted virus causing cytological alterations that precede cervical cancer. Approximately 130 genotypes have been sequenced. Low-grade squamous intraepithelial lesions (LSIL) are the most frequent cytological alteration and have an uncertain behavior. OBJECTIVES: To analyze the frequency of HPV types in LSIL and their association with the regression, persistence or progression of these lesions. METHODS: A cohort study of forty patients with LSIL cytology was conducted from December 2007 to March 2011. The follow-up lasted two years and included cytology and colposcopy. HPV detection was performed using PCR, and genotyping was performed using PCR-specific and RFLP techniques. RESULTS: DNA-HPV was detected in 87% (35/40) of the cases, with oncogenic HPV accounting for 76%; type 16 in 32% (11/35) and type 18 in 20%. LSIL regression, persistence and progression rates at the end of the study were 60%, 23% and 17%, respectively. There was 50% regression in lesions in the high oncogenic risk group (types 16 and 18). CONCLUSION: HPV 16 was the most frequent genotype found in LSIL. The persistence and progression of the LSIL were related to the persistence of oncogenic HPV. The longer the follow-up time, the lower the LSIL persistence rate and the higher its regression rate; the progression rate remained stable. In addition to the presence of oncogenic HPV, other factors are necessary for the progression of LSIL.


Asunto(s)
Infecciones por Papillomavirus/virología , Lesiones Intraepiteliales Escamosas de Cuello Uterino/patología , Lesiones Intraepiteliales Escamosas de Cuello Uterino/virología , Progresión de la Enfermedad , Femenino , Genotipo , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
8.
J Mal Vasc ; 40(1): 10-7, 2015 Feb.
Artículo en Francés | MEDLINE | ID: mdl-25631643

RESUMEN

AIM: Masked hypertension (MH) is defined by a normal office blood pressure (BP) and a high ambulatory BP. MH is characterized by high prevalence and poor cardiovascular prognosis. The aim of this study was to evaluate the usefulness of routine MH screening, using 24-h blood pressure monitoring (BPM), among patients with peripheral arterial disease (PAD). METHODS: Between 2011 and 2013, 54 patients with PAD were included in the Hypertension and Vascular Medicine Unit of the Lille Hospital. They had normal office BP (< 140/90mmHg). A 24 h-BPM device was set on each patient. MH diagnosis was established if the BP average over 24 hours was ≥ 130/80 mmHg and/or the daytime average ≥ 135/85 mmHg and/or the nighttime average ≥ 120/70 mmHg. RESULTS: MH prevalence was about 42.6% (23 patients). It was significantly more frequent in diabetic patients (odds ratio: 3.8 [1.1-12.8]), in patients with known hypertension (odds ratio: 5 [1.5-16.9]) or with high normal office BP (<140/90 mmHg but ≥ 130/85 mmHg) (odds ratio: 5.6 [1.7-18.2]). By multivariate analysis, only known hypertension and high normal office BP were associated with masked hypertension. CONCLUSION: The high prevalence of MH in patients with PAD shows us the importance of a careful screening of MH in this population, especially in diabetic patients, in patients with known hypertension or with a high normal office BP.


Asunto(s)
Hipertensión Enmascarada/diagnóstico , Enfermedad Arterial Periférica/complicaciones , Enfermedad Arterial Periférica/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Complicaciones de la Diabetes/epidemiología , Diabetes Mellitus/fisiopatología , Femenino , Francia/epidemiología , Humanos , Masculino , Hipertensión Enmascarada/epidemiología , Tamizaje Masivo , Persona de Mediana Edad , Oportunidad Relativa , Proyectos Piloto
9.
Biol Reprod ; 92(2): 43, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25537371

RESUMEN

The objective of this study was to compare the effects of systemic and local estrogen treatment on collagen assembly and biomechanical properties of the vaginal wall. Ovariectomized nulliparous rats were treated with estradiol or conjugated equine estrogens (CEEs) either systemically, vaginal CEE, or vaginal placebo cream for 4 wk. Low-dose local CEE treatment resulted in increased vaginal epithelial thickness and significant vaginal growth without uterine hyperplasia. Furthermore, vaginal wall distensibility increased without compromise of maximal force at failure. Systemic estradiol resulted in modest increases in collagen type I with no change in collagen type III mRNA. Low-dose vaginal treatment, however, resulted in dramatic increases in both collagen subtypes whereas moderate and high dose local therapies were less effective. Consistent with the mRNA results, low-dose vaginal estrogen resulted in increased total and cross-linked collagen content. The inverse relationship between vaginal dose and collagen expression may be explained in part by progressive downregulation of estrogen receptor-alpha mRNA with increasing estrogen dose. We conclude that, in this menopausal rat model, local estrogen treatment increased total and cross-linked collagen content and markedly stimulated collagen mRNA expression in an inverse dose-effect relationship. High-dose vaginal estrogen resulted in downregulation of estrogen receptor-alpha and loss of estrogen-induced increases in vaginal collagen. These results may have important clinical implications regarding the use of local vaginal estrogen therapy and its role as an adjunctive treatment in women with loss of vaginal support.


Asunto(s)
Colágeno/metabolismo , Estradiol/administración & dosificación , Estrógenos Conjugados (USP)/administración & dosificación , Vagina/efectos de los fármacos , Administración Intravaginal , Administración Oral , Animales , Fenómenos Biomecánicos/efectos de los fármacos , Femenino , Ratas , Útero/efectos de los fármacos , Útero/metabolismo , Vagina/metabolismo , Cremas, Espumas y Geles Vaginales
10.
Eur J Cancer ; 50(16): 2846-54, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25155250

RESUMEN

AIM: This work describes the human papillomavirus (HPV) prevalence and the HPV type distribution in a large series of vaginal intraepithelial neoplasia (VAIN) grades 2/3 and vaginal cancer worldwide. METHODS: We analysed 189 VAIN 2/3 and 408 invasive vaginal cancer cases collected from 31 countries from 1986 to 2011. After histopathological evaluation of sectioned formalin-fixed paraffin-embedded samples, HPV DNA detection and typing was performed using the SPF-10/DNA enzyme immunoassay (DEIA)/LiPA25 system (version 1). A subset of 146 vaginal cancers was tested for p16(INK4a) expression, a cellular surrogate marker for HPV transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance. RESULTS: HPV DNA was detected in 74% (95% confidence interval (CI): 70-78%) of invasive cancers and in 96% (95% CI: 92-98%) of VAIN 2/3. Among cancers, the highest detection rates were observed in warty-basaloid subtype of squamous cell carcinomas, and in younger ages. Concerning the type-specific distribution, HPV16 was the most frequently type detected in both precancerous and cancerous lesions (59%). p16(INK4a) overexpression was found in 87% of HPV DNA positive vaginal cancer cases. CONCLUSIONS: HPV was identified in a large proportion of invasive vaginal cancers and in almost all VAIN 2/3. HPV16 was the most common type detected. A large impact in the reduction of the burden of vaginal neoplastic lesions is expected among vaccinated cohorts.


Asunto(s)
Carcinoma de Células Escamosas/virología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Neoplasias Vaginales/virología , Anciano , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/epidemiología , Estudios Transversales , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , ADN Viral/análisis , Femenino , Papillomavirus Humano 16/aislamiento & purificación , Humanos , Técnicas para Inmunoenzimas , Cooperación Internacional , Persona de Mediana Edad , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Distribución de Poisson , Lesiones Precancerosas/epidemiología , Lesiones Precancerosas/virología , Prevalencia , Análisis de Regresión , Estudios Retrospectivos , Resultado del Tratamiento , Neoplasias Vaginales/complicaciones , Neoplasias Vaginales/epidemiología
11.
Neuroscience ; 272: 188-98, 2014 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-24814729

RESUMEN

Glutamate-induced excitotoxicity involves a state of acute oxidative stress, which is a crucial event during neuronal degeneration and is part of the physiopathology of neurodegenerative diseases. In this work, we evaluated the ability of sulforaphane (SULF), a natural dietary isothiocyanate, to induce the activation of transcription factor Nrf2 (a master regulator of redox state in the cell) in a model of striatal degeneration in rats infused with quinolinic acid (QUIN). Male Wistar rats received SULF (5mg/kg, i.p.) 24h and 5min before the intrastriatal infusion of QUIN. SULF increased the reduced glutathione (GSH) levels 4h after QUIN infusion, which was associated with its ability to increase the activity of glutathione reductase (GR), an antioxidant enzyme capable to regenerate GSH levels at 24h. Moreover, SULF treatment increased glutathione peroxidase (GPx) activity, while no changes were observed in γ-glutamyl cysteine ligase (GCL) activity. SULF treatment also prevented QUIN-induced oxidative stress (measured by oxidized proteins levels), the histological damage and the circling behavior. These results suggest that the protective effect of SULF could be related to its ability to preserve GSH levels and increase GPx and GR activities.


Asunto(s)
Anticarcinógenos/farmacología , Glutatión/metabolismo , Isotiocianatos/farmacología , Ácido Quinolínico/metabolismo , Animales , Glutatión Reductasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Enfermedades Neurodegenerativas/metabolismo , Ratas Wistar , Sulfóxidos
12.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 41(1): 42-44, ene.-mar. 2014. ilus
Artículo en Español | IBECS | ID: ibc-118102

RESUMEN

Se presentan 2 casos clínicos referentes a pacientes prepúberes con un cuadro clínico caracterizado por la aparición de úlceras vulvares asociadas con síntomas sistémicos y orofaríngeos en los días anteriores a la aparición de dichas úlceras. Se intenta ahondar en la importancia del diagnóstico diferencial entre las diferentes enfermedades infecciosas de transmisión sexual, siendo de vital importancia descartar la posibilidad de abusos sexuales en estas pacientes. La aparición de la úlcera vulvar aguda es rara, a menudo es infradiagnosticada por su baja incidencia y su difícil diagnóstico. Aunque es un cuadro autolimitado, el tratamiento temprano es importante para minimizar la sintomatología que se deriva. El diagnóstico se basa en la clínica y la exclusión de otras causas responsables de la aparición de úlceras vulvares. El tratamiento se fundamenta en la administración de antiinflamatorios y/o antipiréticos. También pueden administrarse anestésicos locales tópicos. La mayoría de las pacientes pueden tratarse de forma ambulatoria pero en ocasiones requieren ingreso para sondaje vesical, debido a la imposibilidad para la micción derivada del dolor que esto ocasiona


We present the cases of two prepubertal girls with a clinical picture characterized by systemic and oropharyngeal symptoms a few days before the appearance of vulvar ulcers. We aim to highlight the importance of performing a differential diagnosis among distinct sexually-transmitted diseases and of excluding the possibility of sexual abuse in these patients. The development of acute vulvar ulcer is rare and this entity is often underdiagnosed because of its low incidence and difficult diagnosis. Although this process is self-limiting, early treatment is important to minimize symptoms. Diagnosis is based on clinical findings and the exclusion of other causes of genital ulcers. Treatment is based on the administration of anti-inflammatory and/or antipyretic agents. Local topical anesthetics can also be used. Most patients can be treated as outpatients. If urination is impossible due to pain, hospital admission may be required for catheterization


Asunto(s)
Humanos , Femenino , Niño , Adolescente , Enfermedades de la Vulva/diagnóstico , Úlcera Cutánea/diagnóstico , Faringitis/complicaciones , Diagnóstico Diferencial , Micción/fisiología , Retención Urinaria/etiología
14.
Neuroscience ; 252: 384-95, 2013 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-23988432

RESUMEN

The aim of this study was to analyze the effects of chronic oxidative stress on mitochondrial function and its relationship to progressive neurodegeneration in the hippocampus of rats chronically exposed to ozone. Animals were exposed to 0.25 ppm ozone for 7, 15, 30, or 60 days. Each group was tested for (1) protein oxidation and, manganese superoxide dismutase (Mn-SOD), glutathione peroxidase (GPx) and succinate dehydrogenase (SDH) activity using spectrophotometric techniques, (2) oxygen consumption, (3) cytochrome c, inducible nitric oxide synthase (iNOS), peroxisome proliferator-activated receptor γ Co-activator 1α (PGC-1α), B-cell lymphoma (Bcl-2), and Bax expression using Western blotting, (4) histology using hematoxylin and eosin staining, and (5) mitochondrial structure using electron microscopy. Our results showed increased levels of carbonyl protein and Mn-SOD activity after 30 days of ozone exposure and decreased GPx activity. The SDH activity decreased from 7 to 60 days of exposure. The oxygen consumption decreased at 60 days. Western blotting showed an increase in cytochrome c at 60 days of ozone exposure and an increase in iNOS up to 60 days of ozone exposure. The expression of PGC-1α was decreased after 15, 30, and 60 days compared to the earlier time Bcl-2 was increased at 60 days compared to earlier time points, and Bax was increased after 30 and 60 days of exposure compared to earlier time points. We observed cellular damage, and mitochondrial swelling with a loss of mitochondrial cristae after 60 days of exposure. These changes suggest that low doses of ozone caused mitochondrial abnormalities that may lead to cell damage.


Asunto(s)
Hipocampo/metabolismo , Hipocampo/patología , Mitocondrias/metabolismo , Mitocondrias/patología , Estrés Oxidativo/fisiología , Animales , Western Blotting , Inmunohistoquímica , Oxidantes Fotoquímicos/toxicidad , Ozono/toxicidad , Ratas , Ratas Wistar
15.
Nat Nanotechnol ; 8(4): 256-60, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23542903

RESUMEN

In spin-based electronics, information is encoded by the spin state of electron bunches. Processing this information requires the controlled transport of spin angular momentum through a solid, preferably at frequencies reaching the so far unexplored terahertz regime. Here, we demonstrate, by experiment and theory, that the temporal shape of femtosecond spin current bursts can be manipulated by using specifically designed magnetic heterostructures. A laser pulse is used to drive spins from a ferromagnetic iron thin film into a non-magnetic cap layer that has either low (ruthenium) or high (gold) electron mobility. The resulting transient spin current is detected by means of an ultrafast, contactless amperemeter based on the inverse spin Hall effect, which converts the spin flow into a terahertz electromagnetic pulse. We find that the ruthenium cap layer yields a considerably longer spin current pulse because electrons are injected into ruthenium d states, which have a much lower mobility than gold sp states. Thus, spin current pulses and the resulting terahertz transients can be shaped by tailoring magnetic heterostructures, which opens the door to engineering high-speed spintronic devices and, potentially, broadband terahertz emitters.

16.
Nat Mater ; 12(4): 332-6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23353629

RESUMEN

Irradiating a ferromagnet with a femtosecond laser pulse is known to induce an ultrafast demagnetization within a few hundred femtoseconds. Here we demonstrate that direct laser irradiation is in fact not essential for ultrafast demagnetization, and that electron cascades caused by hot electron currents accomplish it very efficiently. We optically excite a Au/Ni layered structure in which the 30 nm Au capping layer absorbs the incident laser pump pulse and subsequently use the X-ray magnetic circular dichroism technique to probe the femtosecond demagnetization of the adjacent 15 nm Ni layer. A demagnetization effect corresponding to the scenario in which the laser directly excites the Ni film is observed, but with a slight temporal delay. We explain this unexpected observation by means of the demagnetizing effect of a superdiffusive current of non-equilibrium, non-spin-polarized electrons generated in the Au layer.

17.
Neuroscience ; 231: 91-101, 2013 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-23201824

RESUMEN

Quinolinic acid (QA)-induced overactivation of N-methyl-d-aspartate receptors yields excitotoxicity, oxidative stress and mitochondrial dysfunction, which altogether contribute to trigger a wide variety of toxic pathways with biochemical, behavioral and neuropathological alterations similar to those observed in Huntington's disease. Noteworthy, in the brains of these patients, increased expression of heme oxygenase-1 (HO-1) levels can be found. It has been proposed that this enzyme can exert a dual role, as it can be either protective or deleterious to the CNS. While some evidence indicates that its overexpression affords cellular anti-oxidant protection due to decreased concentrations of its pro-oxidative substrate heme group, and increased bilirubin levels, other reports established that high HO-1 expression and activity may result in a pro-oxidizing atmosphere due to a release of Fe(2+). In this work, we examined the temporal evolution of oxidative damage to proteins, HO-1 expression, immunoreactivity, total activity, and cell death after 1, 3, 5 and 7 days of an intrastriatal QA infusion (240 nmol/µl). QA was found to induce cellular degeneration, increasing carbonylated proteins and generating a transitory response in HO-1 mRNA, protein content, and immunoreactivity and activity in nerve cells. In order to study the role of HO-1 in the QA-induced cellular death, the tin protoporphyrin IX (SnPP), a well-known HO inhibitor, was administered to rats (30 µmol/kg, i.p.). The administration of SnPP to animals treated with QA inhibited the HO activation, and exacerbated the striatal cell damage induced by QA. Our findings reveal a potential modulatory role of HO-1 in the toxic paradigm evoked by QA in rats. This evidence provides a valuable tool for further approaches on HO-1 regulation in neurotoxic paradigms.


Asunto(s)
Cuerpo Estriado/metabolismo , Hemo-Oxigenasa 1/antagonistas & inhibidores , Degeneración Nerviosa/metabolismo , Estrés Oxidativo/fisiología , Regulación hacia Arriba/fisiología , Animales , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/patología , Hemo-Oxigenasa 1/metabolismo , Masculino , Metaloporfirinas/farmacología , Degeneración Nerviosa/inducido químicamente , Degeneración Nerviosa/patología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Protoporfirinas/farmacología , Ácido Quinolínico , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba/efectos de los fármacos
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