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1.
Med Klin Intensivmed Notfmed ; 118(1): 54-61, 2023 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-34709427

RESUMEN

BACKGROUND: Fast access to information from other healthcare service providers is particularly important in emergency medicine, as the patients are often unknown and treatment decisions have to be made promptly. OBJECTIVES: The study aims to identify the challenges that emergency departments face in obtaining information on patient history, the expected benefits of easier access to information and which information is most urgently needed. MATERIALS AND METHODS: An online survey throughout Germany was carried out among medical staff working in emergency departments. In all, 181 questionnaires were fully completed and could be included in the data analysis. RESULTS: Of the respondents, 77.9% said it was difficult or very difficult to receive external data at the point of patient care. The survey participants estimate that they need an average of around 47 min to obtain information about one patient. 99.4% believe that patient care would benefit from an easier and faster information exchange. Medication lists, discharge letters, information on previous illnesses and allergies were classified as the most important data elements. CONCLUSIONS: There is an urgent need for action with regard to the considerable effort involved in obtaining information on emergency patients. Digital solutions such as the recently introduced emergency data set can offer additional value for clinical emergency care if they are widely used.


Asunto(s)
Medicina de Emergencia , Servicio de Urgencia en Hospital , Humanos , Encuestas y Cuestionarios , Alemania
2.
Cryo Letters ; 41(3): 128-134, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33988641

RESUMEN

BACKGROUND: Some antioxidants have been used in semen extenders to reduce adverse effects caused by excessive reactive oxygen species (ROS) production. The study was carried out to assess the effect of quercetin (QC) antioxidant therapy on goat semen submitted to cryopreservation. OBJECTIVE: To evaluate the effect of quercetin incorporation in different phases of the cryopreservation process of goat spermatozoa. MATERIALS AND METHODS: Five ejaculates from each of four goats (n= 20) were collected and split into four groups: Control (G1), without QC; G2, 15 µM of QC added to semen before centrifugation; G3, 15 µM QC added to semen after centrifugation; G4, 15 µM QC added to semen before centrifugation and 15 µM of QC added to semen after centrifugation (total of 30 µM of QC); and cryopreserved. All semen samples were evaluated after thawing for sperm kinetics, plasma membrane integrity, and ROS levels. RESULTS: Although lower concentrations of ROS were associated with groups that received antioxidant supplementation (P=0.0213), linear and dose dependent (P<0.05) reductions of the total and progressive sperm motility, velocity and percentage of fast cells were related to the QC groups. Likewise, plasma membrane integrity was better preserved (P=0.0154) in the control group (35.5%) than in groups that received QC (G2=32.6%, G3=32.4% and G4=26.7%). CONCLUSION: Although quercetin was efficient at reducing the oxidative stress related to sperm cryopreservation, it exerted a deleterious dose-dependent effect on the kinetics and integrity of the frozen goat semen, contradicating its use in the tested concentrations.


Asunto(s)
Antioxidantes , Criopreservación , Quercetina , Preservación de Semen , Animales , Antioxidantes/farmacología , Criopreservación/veterinaria , Cabras , Masculino , Quercetina/farmacología , Semen , Análisis de Semen/veterinaria , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides
3.
Neuropsychopharmacology ; 43(11): 2292-2298, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30046156

RESUMEN

Although sleep-dependent consolidation and its neurochemical underpinnings have been strongly researched, less is known about how consolidation during sleep affects subsequent learning. Since sleep enhances memory, it can be expected to pro-actively interfere with learning after sleep, in particular of similar materials. This pro-active interference should be enhanced by substances that benefit consolidation during sleep, such as D-cycloserine. We tested this hypothesis in two groups (Sleep, Wake) of young healthy participants receiving on one occasion D-cycloserine (175 mg) and on another occasion placebo, according to a double-blind balanced crossover design. Treatment was administered after participants had learned a set of word pairs (A-B list) and before nocturnal retention periods of sleep vs. wakefulness. After D-cycloserine blood plasma levels had dropped to negligible amounts, i.e., the next day in the evening, participants learned, in three sequential runs, new sets of word pairs. One list-to enhance interference-consisted of the same cue words as the original set paired with a new target word (A-C list) and the other of completely new cue words (D-E set). Unexpectedly, during post-retention learning the A-C interference list was generally better learned than the completely new D-E list, which suggests that consolidation of previously encoded similar material enhances memory integration rather than pro-active interference. Consistent with this view, new learning of word pairs was better after sleep than wakefulness. Similarly, D-cycloserine generally enhanced learning of new word pairs, compared to placebo. This effect being independent of sleep or wakefulness, leads us to speculate that D-cycloserine, in addition to enhancing sleep-dependent consolidation, might mediate a time-dependent process of active forgetting.


Asunto(s)
Aprendizaje/fisiología , Consolidación de la Memoria/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Sueño/fisiología , Vigilia/fisiología , Adolescente , Adulto , Estudios Cruzados , Cicloserina/farmacología , Método Doble Ciego , Electroencefalografía/métodos , Humanos , Aprendizaje/efectos de los fármacos , Masculino , Consolidación de la Memoria/efectos de los fármacos , Polisomnografía/métodos , Sueño/efectos de los fármacos , Vigilia/efectos de los fármacos , Adulto Joven
4.
Rev Med Liege ; 72(9): 399-405, 2017 Sep.
Artículo en Francés | MEDLINE | ID: mdl-28892315

RESUMEN

Many case studies reported psychiatric symptoms during the months before a brain tumor (BT) is diagnosed. Unfortunately, these symptoms are rarely considered as a warning of an organic problem and patients are regularly misoriented towards psychiatric care. Knowing better what psychiatric symptoms look like in patients with a BT would help to diagnose it sooner, which would obviously benefit the patient. The present study aims to quantify the prevalence and further describe psychiatric symptoms occurring before a BT diagnosis. The presence of psychiatric manifestations was systematically investigated in 100 patients with a first diagnosis of BT. Overall, 85 % of the patients reported at least one psychiatric symptom present before the BT diagnosis, most often depressive ones. Somatic manifestations of depression (loss of energy, changes in appetite...) were more often reported than affective or cognitive ones (no negative thought content: no pessimism, no guilty feelings, no worthlessness…). The present research stresses the high prevalence of psychiatric symptoms, especially depressive-like ones, occurring before a BT is diagnosed and provides a first description of these symptoms, as a basis of practical recommendations.


De nombreuses études de cas ont rapporté la présence de symptômes psychiatriques dans les mois qui précèdent le diagnostic d'une tumeur cérébrale (TC). Malheureusement, ces symptômes restent rarement considérés comme renseignant un possible problème organique et les patients sont régulièrement orientés vers une prise en charge psychiatrique. Une meilleure connaissance de la présentation psychiatrique des TC favoriserait un diagnostic précoce, évidemment profitable au patient. L'objectif de cette étude est de quantifier la fréquence des symptômes psychiatriques présents avant le diagnostic de TC et de les décrire. Chez 100 patients adultes avec un premier diagnostic de TC, la présence de manifestations psychiatriques a été évaluée de façon systématique. 85 % des patients ont souffert d'au moins un symptôme psychiatrique avant que la TC ne soit diagnostiquée, avec, à l'avant-plan des éléments dépressifs. Parmi les symptômes dépressifs, les expressions somatiques sont le plus souvent rapportées (perte d'énergie, changement de l'appétit…), au contraire des manifestations cognitives et affectives (pas de contenu de pensées négatives : pessimisme, culpabilité, dévalorisation...). Cette recherche souligne la prévalence élevée de symptômes psychiatriques évoquant le plus souvent un état dépressif avant le diagnostic de TC et apporte une première description de ces symptômes, permettant l'ébauche de certaines recommandations pratiques.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Trastornos Mentales/diagnóstico , Anciano , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/psicología , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Meníngeas/complicaciones , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/psicología , Meningioma/complicaciones , Meningioma/diagnóstico , Meningioma/psicología , Trastornos Mentales/etiología
5.
Sci Rep ; 6: 34608, 2016 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-27708362

RESUMEN

Atherosclerotic plaques are classically divided into stable and vulnerable plaques. Vulnerable plaques are prone to rupture with a risk for infarction. High intraplaque microvessel density predisposes to plaque vulnerability. Hydrogen sulfide (H2S) is a proangiogenic gasotransmitter which is endogenously produced by cystathionine γ-lyase (CSE), and is believed to have vasculoprotective effects. However, due to its proangiogenic effects, H2S may result in pathological angiogenesis in atherosclerotic plaques, thereby increasing plaque vulnerability. The aim of this study was to determine CSE expression pattern in atherosclerotic plaques, and investigate whether CSE is involved in micro-angiogenesis in vitro. Endarterectomy plaques were studied for CSE expression, and the role of CSE in micro-angiogenesis was studied in vitro. CSE is expressed in plaques with similar levels in both stable and vulnerable plaques. CSE co-localized with von Willebrand Factor-positive microvessel endothelial cells and alpha-smooth-muscle actin-positive SMCs. In vitro, inhibition of CSE in HMEC-1 reduced tube formation, cell viability/proliferation, and migration which was restored after culture in the presence of H2S donor GYY4137. CSE is expressed in intraplaque microvessels, and H2S is a stimulator of micro-angiogenesis in vitro. Due to this pro-angiogenic effect, high levels of CSE in atherosclerotic plaques may be a potential risk for plaque vulnerability.


Asunto(s)
Cistationina gamma-Liasa/biosíntesis , Regulación Enzimológica de la Expresión Génica , Microvasos/enzimología , Neovascularización Patológica/enzimología , Placa Aterosclerótica/enzimología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Microvasos/patología , Persona de Mediana Edad , Neovascularización Patológica/patología , Placa Aterosclerótica/patología
6.
Int J Obes (Lond) ; 40(11): 1707-1714, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27553712

RESUMEN

BACKGROUND/OBJECTIVES: Animal studies and pilot experiments in men indicate that the hypothalamic neuropeptide oxytocin limits food intake, and raise the question of its potential to improve metabolic control in obesity. SUBJECTS/METHODS: We compared the effect of central nervous oxytocin administration (24 IU) via the intranasal route on ingestive behaviour and metabolic function in 18 young obese men with the results in a group of 20 normal-weight men. In double-blind, placebo-controlled experiments, ad libitum food intake from a test buffet was examined in fasted subjects 45 min after oxytocin administration, followed by the assessment of postprandial, reward-driven snack intake. Energy expenditure was repeatedly assessed by indirect calorimetry and blood was sampled to determine concentrations of blood glucose and hormones. RESULTS: Oxytocin markedly reduced hunger-driven food intake in the fasted state in obese but not in normal-weight men, and led to a reduction in snack consumption in both groups, whereas energy expenditure remained generally unaffected. Hypothalamic-pituitary-adrenal axis secretion and the postprandial rise in plasma glucose were blunted by oxytocin in both groups. CONCLUSIONS: Oxytocin exerts an acutely inhibitory impact on food intake that is enhanced rather than decreased in obese compared with normal-weight men. This pattern puts it in contrast to other metabolically active neuropeptides and bodes well for clinical applications of oxytocin in the treatment of metabolic disorders.


Asunto(s)
Depresores del Apetito/farmacología , Ingestión de Alimentos/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Obesidad/fisiopatología , Oxitocina/farmacología , Administración Intranasal , Adulto , Depresores del Apetito/administración & dosificación , Estudios de Casos y Controles , Estudios Cruzados , Método Doble Ciego , Ingestión de Alimentos/fisiología , Ingestión de Alimentos/psicología , Ingestión de Energía/efectos de los fármacos , Ingestión de Energía/fisiología , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/fisiología , Conducta Alimentaria/fisiología , Alemania , Humanos , Sistema Hipotálamo-Hipofisario , Masculino , Obesidad/tratamiento farmacológico , Obesidad/prevención & control , Oxitocina/administración & dosificación , Sistema Hipófiso-Suprarrenal , Periodo Posprandial/fisiología , Resultado del Tratamiento
7.
Rev Med Liege ; 71(3): 120-3, 2016 Mar.
Artículo en Francés | MEDLINE | ID: mdl-27311242

RESUMEN

The lacunar skull is a radiologic description characterised by the presence of lacunae in the cranial vault. Its physiopathology remains up to now poorly understood; it is mostly associated with neural tube defects. The association of a lacunar skull with a craniosynostosis has rarely been described in the literature. The case of a 9-month-old patient presenting a multisutural craniosynostosis with a lacunar skull is reported in this article. The surgical treatment allowed to remodel the skull and to hope for a spontaneous regression of the lacunae.


Asunto(s)
Craneosinostosis/complicaciones , Cráneo/anomalías , Craneosinostosis/fisiopatología , Humanos , Lactante , Masculino , Cráneo/cirugía , Tomografía Computarizada por Rayos X
8.
Neurochirurgie ; 61(4): 279-82, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26072230

RESUMEN

Failure of the anterior neuropore can lead to three main types of anomalies: nasal dermal sinus, encephalocele and nasal glioma or heterotopia. In this report, we describe a case of intracranial and extracranial glial heterotopia that probably resulted from a common failure of anterior neuropore development. We describe the prenatal radiological assessment based on ultrasound and MRI results, and consider their limitation for early fetal diagnosis. We also discuss the embryogenesis and the possible pathogenic mechanisms involved.


Asunto(s)
Astrocitoma/cirugía , Glioma/cirugía , Neoplasias Nasales/cirugía , Astrocitoma/diagnóstico , Diagnóstico Diferencial , Encefalocele/diagnóstico , Encefalocele/cirugía , Glioma/diagnóstico , Humanos , Lactante , Imagen por Resonancia Magnética/métodos , Masculino , Neoplasias Nasales/diagnóstico
9.
Neurobiol Learn Mem ; 122: 122-30, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25180933

RESUMEN

Sleep benefits the consolidation of emotional memories, and this influence is commonly attributed to the rapid eye movement (REM) stage of sleep. However, the contributions of sleep stages to memory for an emotional episode may differ for the event per se (i.e., item memory), and the context in which it occurred (source memory). Here, we examined the effects of slow wave sleep (SWS) and REM sleep on the consolidation of emotionally negative and neutral item (picture recognition) and source memory (recall of picture-location and picture-frame color association) in humans. In Study 1, the participants (n=18) learned 48 negative and 48 neutral pictures which were presented at specific locations and preceded by colored frames that had to be associated with the picture. In a within-subject design, learning was either followed by a 3-h early-night SWS-rich or by a late-night REM sleep-rich retention interval, then retrieval was tested. Only after REM-rich sleep, and not after SWS-rich sleep, was there a significant emotional enhancement, i.e., a significantly superior retention of emotional over neutral pictures. On the other hand, after SWS-rich sleep the retention of picture-frame color associations was better than after REM-rich sleep. However, this benefit was observed only for neutral pictures; and it was completely absent for the emotional pictures. To examine whether this absent benefit reflected a suppressive effect of emotionality on associations of minor task relevance, in Study 2 we manipulated the relevance of the picture-frame color association by combining it with information about monetary reward, following otherwise comparable procedures. Here, rewarded picture-frame color associations were equally well retained over SWS-rich early sleep no matter if the frames were associated with emotional or neutral pictures. Results are consistent with the view that REM sleep favors the emotional enhancement of item memory whereas SWS appears to contribute primarily to the consolidation of context-color information associated with the item.


Asunto(s)
Emociones/fisiología , Consolidación de la Memoria/fisiología , Fases del Sueño/fisiología , Adolescente , Adulto , Encéfalo/fisiología , Electroencefalografía , Femenino , Humanos , Masculino , Recuerdo Mental/fisiología , Reconocimiento en Psicología/fisiología , Sueño REM/fisiología , Adulto Joven
10.
Immunobiology ; 220(5): 673-83, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25476849

RESUMEN

In chronic transplant dysfunction (CTD), persistent (allo)immune-mediated inflammation eventually leads to tissue remodeling including neointima formation in intragraft arteries. We previously showed that recipient-derived neointimal α-SMA(+) smooth muscle-like cells are present in human renal allografts with CTD. Human PBMC contain myeloid cells capable of differentiating into α-SMA(+) cells in vitro; the phenotype of the ancestral subset is as yet unknown. This study aimed to investigate whether monocyte subsets contain cells with smooth muscle-like cell differentiation capacity and whether CTD in renal transplant recipients is associated with a shift in these monocyte subsets. To accomplish this goal, monocyte subsets from healthy controls were sorted based on CD14 and CD16 expression to investigate gene expression levels of mesenchymal markers α-SMA and SM22α. CD14(+)/CD16(++) monocytes displayed increased α-SMA and SM22α mRNA expression compared with CD14(++)/CD16(-) monocytes, suggesting increased differentiation potential toward smooth muscle-like cells. Flow cytometry revealed that in non-CTD transplant recipients the percentage of CD14(+)/CD16(++) monocytes was reduced, with an even further reduction in patients with CTD. To determine a potential correlation between CD14(+)/CD16(++) monocytes and α-SMA(+) cell outgrowth potential in vitro, PBMC of healthy controls and transplant recipients with and without CTD were cultured under fibrotic culture conditions, and indeed a significant correlation (p=0.0002, r=0.62) was observed. Finally, double staining for α-SMA and CD16 revealed presence of α-SMA(+)CD16(+) cells in kidney explants from CTD patients, albeit at very low numbers. Our data represent evidence that, compared to CD14(++)CD16(-) monocytes, CD14(+)CD16(++) monocytes have an increased expression of smooth muscle cell-associated genes. This monocyte subpopulation is reduced in renal transplant patients with CTD, possibly due to selective migration into the allograft.


Asunto(s)
Actinas/metabolismo , Aloinjertos/inmunología , Rechazo de Injerto/inmunología , Trasplante de Riñón , Proteínas de Microfilamentos/metabolismo , Monocitos/inmunología , Proteínas Musculares/metabolismo , Miocitos del Músculo Liso/inmunología , Neointima/inmunología , Complicaciones Posoperatorias/inmunología , Actinas/genética , Aloinjertos/irrigación sanguínea , Diferenciación Celular , Enfermedad Crónica , Rechazo de Injerto/etiología , Humanos , Receptores de Lipopolisacáridos/metabolismo , Proteínas de Microfilamentos/genética , Monitorización Inmunológica/métodos , Proteínas Musculares/genética , Neointima/etiología , Receptores de IgG/metabolismo
11.
Am J Transplant ; 14(10): 2328-38, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25154787

RESUMEN

Syndecan-1 is a transmembrane heparan sulfate (HS) proteoglycan present on hepatocytes and involved in uptake of triglyceride-rich lipoproteins via its HS polysaccharide side chains. We hypothesized that altered hepatic syndecan-1 metabolism could be involved in dyslipidemia related to renal transplantation. In a rat renal transplantation model elevated plasma triglycerides were associated with fivefold increased expression of hepatic syndecan-1 mRNA (p < 0.01), but not protein. Expression of syndecan-1 sheddases (ADAM17, MMP9) and heparanase was significantly up-regulated after renal transplantation (all p < 0.05). Profiling of HS side chains revealed loss of hepatic HS upon renal transplantation accompanied by significant decreased functional capacity for VLDL binding (p = 0.02). In a human renal transplantation cohort (n = 510), plasma levels of shed syndecan-1 were measured. Multivariate analysis showed plasma syndecan-1 to be independently associated with triglycerides (p < 0.0001) and inversely with HDL cholesterol (p < 0.0001). Last, we show a physical association of syndecan-1 to HDL from renal transplant recipients (RTRs), but not to HDL from healthy controls. Our data suggest that after renal transplantation loss of hepatic HS together with increased syndecan-1 shedding hampers lipoprotein binding and uptake by the liver contributing to dyslipidemia. Our data open perspectives toward improvement of lipid profiles by targeted inhibition of syndecan-1 catabolism in renal transplantation.


Asunto(s)
Dislipidemias/metabolismo , Trasplante de Riñón , Hígado/metabolismo , Sindecano-1/metabolismo , Animales , Femenino , Masculino , Ratas , Ratas Wistar
12.
Diabetes Obes Metab ; 16(12): 1274-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25059854

RESUMEN

The attenuated counter-regulatory response to hypoglycaemia after antecedent hypoglycaemic episodes has been observed in animals to be associated with an increase in γ-aminobutyric acid (GABA) signalling. We therefore tested the hypothesis that the pharmacological suppression of GABAergic activity during a repeated hypoglycaemic episode enhances counter-regulatory responses. Fourteen healthy men participated in two experimental sessions each comprising three insulin-induced hypoglycaemic episodes. Before the third hypoglycaemic episode, participants received the GABA-antagonistic drug modafinil (200 mg orally) and placebo, respectively. In the placebo condition, the secretion of norepinephrine, adrenocorticotropic hormone, cortisol and growth hormone, and the perception of neuroglycopenic symptoms were attenuated during the third as compared with the first hypoglycaemic episode (each p < 0.05). Modafinil reversed this effect for the noradrenergic response (p < 0.05), while not significantly altering the attenuation of other hormonal responses and symptom perception (p > 0.3). Our findings indicate that increased GABAergic transmission could contribute to aspects of the attenuated counter-regulatory response after recurrent hypoglycaemia in humans.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Glucemia/metabolismo , Inductores del Citocromo P-450 CYP3A/farmacología , Hipoglucemia/inducido químicamente , Transducción de Señal/efectos de los fármacos , Ácido gamma-Aminobutírico/efectos de los fármacos , Hormona Adrenocorticotrópica/sangre , Hormona Adrenocorticotrópica/efectos de los fármacos , Adulto , Análisis de Varianza , Compuestos de Bencidrilo/administración & dosificación , Glucemia/efectos de los fármacos , Inductores del Citocromo P-450 CYP3A/administración & dosificación , Método Doble Ciego , Hormona del Crecimiento/sangre , Hormona del Crecimiento/efectos de los fármacos , Voluntarios Sanos , Humanos , Hidrocortisona/sangre , Masculino , Modafinilo , Norepinefrina/sangre , Ácido gamma-Aminobutírico/metabolismo
13.
AJNR Am J Neuroradiol ; 35(6): 1232-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24481329

RESUMEN

Adhesive arachnoiditis is a rare condition, often complicated by syringomyelia. This pathologic entity is usually associated with prior spinal surgery, spinal inflammation or infection, and hemorrhage. The usual symptoms of arachnoiditis are pain, paresthesia, and weakness of the low extremities due to the nerve entrapment. A few cases have had no obvious etiology. Previous studies have reported one family with multiple cases of adhesive arachnoiditis. We report a second family of Belgian origin with multiple cases of arachnoiditis and secondary syringomyelia in the affected individuals.


Asunto(s)
Aracnoiditis/congénito , Aracnoiditis/patología , Imagen por Resonancia Magnética , Siringomielia/congénito , Siringomielia/patología , Adolescente , Adulto , Bélgica , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adherencias Tisulares/congénito , Adherencias Tisulares/patología
14.
Neuroimage ; 75: 87-96, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23501052

RESUMEN

Sleep, in particular REM sleep, has been shown to improve the consolidation of emotional memories. Here, we investigated the role of sleep and sleep deprivation on the consolidation of fear memories and underlying neuronal mechanisms. We employed a Pavlovian fear conditioning paradigm either followed by a night of polysomnographically monitored sleep, or wakefulness in forty healthy participants. Recall of learned fear was better after sleep, as indicated by stronger explicitly perceived anxiety and autonomous nervous responses. These effects were positively correlated with the preceding time spent in REM sleep and paralleled by activation of the basolateral amygdala. These findings suggest REM sleep-associated consolidation of fear memory in the human amygdala. In view of the critical participation of fear learning mechanisms in the etiology of anxiety and post-traumatic stress disorder, deprivation of REM sleep after exposure to distressing events is an interesting target for further investigation.


Asunto(s)
Miedo/fisiología , Memoria/fisiología , Privación de Sueño , Sueño REM/fisiología , Adulto , Condicionamiento Clásico , Humanos , Masculino , Polisomnografía , Sueño/fisiología , Adulto Joven
15.
Neurobiol Learn Mem ; 99: 1-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23123802

RESUMEN

Emotional memories are vividly remembered for the long-term. Rapid eye movement (REM) sleep has been repeatedly proposed to support the superior retention of emotional memories. However, its exact contribution and, specifically, whether its effect is mainly on the consolidation of the contents or the processing of the affective component of emotional memories is not clear. Here, we investigated the effects of sleep rich in slow wave sleep (SWS) or REM sleep on the consolidation of emotional pictures and the accompanying changes in affective tone, using event-related potentials (ERPs) together with subjective ratings of valence and arousal. Sixteen healthy, young men learned 50 negative and 50 neutral pictures before 3-h retention sleep intervals that were filled with either SWS-rich early or REM sleep-rich late nocturnal sleep. In accordance with our hypothesis, recognition was better for emotional pictures than neutral pictures after REM compared to SWS-rich sleep. This emotional enhancement after REM-rich sleep expressed itself in an increased late positive potential of the ERP over the frontal cortex 300-500 ms after stimulus onset for correctly classified old emotional pictures compared with new emotional and neutral pictures. Valence and arousal ratings of emotional pictures were not differentially affected by REM or SWS-rich sleep after learning. Our results corroborate that REM sleep contributes to the consolidation of emotional contents in memory, but suggest that the affective tone is preserved rather than reduced by the processing of emotional memories during REM sleep.


Asunto(s)
Encéfalo/fisiología , Emociones/fisiología , Reconocimiento Visual de Modelos/fisiología , Retención en Psicología/fisiología , Sueño REM/fisiología , Sueño/fisiología , Adulto , Afecto/fisiología , Nivel de Alerta/fisiología , Estudios Cruzados , Electroencefalografía , Potenciales Evocados/fisiología , Humanos , Masculino , Memoria/fisiología , Polisomnografía , Tiempo de Reacción , Adulto Joven
16.
Diabetes Obes Metab ; 15(4): 310-5, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23072263

RESUMEN

AIMS: Recurrent hypoglycaemia leads to an attenuation of hypoglycaemic symptoms and hormonal counterregulatory responses. This phenomenon poses a severe problem in the treatment of patients with diabetes mellitus, but the underlying neuroendocrine mechanisms are unclear. On the basis of animal experimental findings, we hypothesized that counterregulatory attenuation represents a basic adaptive learning process relying on synaptic long-term potentiation or depression. If so, attenuation should be prevented by blocking glutamatergic N-methyl-D-aspartate (NMDA) receptors. METHODS: Sixteen healthy young men participated in two conditions, separated by 4 weeks. Participants received the NMDA antagonist memantine over 5 days (15 mg/day) in one condition and placebo in the other one. After 3 days of drug administration, participants underwent two hypoglycaemic clamps on day 4 and another one on day 5. We assessed blood concentrations of counterregulatory hormones (cortisol, ACTH, epinephrine, norepinephrine, growth hormone and glucagon) as well as subjective symptoms of hypoglycaemia and word-list recall as an indicator of short-term memory. RESULTS: Counterregulatory responses of all hormones as well as neuroglycopenic and autonomic symptom ratings showed robust attenuation following the third as compared to the first hypoglycaemia (p < 0.05). NMDA receptor antagonization by memantine impaired memory function but did not alter any neuroendocrine measure of counterregulatory attenuation (p > 0.17). CONCLUSIONS: Attenuation of the endocrine as well as symptomatic counterregulatory response to recurrent hypoglycaemia is not prevented by the NMDA receptor blocker memantine. Our results do not support the view that adaptation to repeated hypoglycaemia relies on NMDA receptor-mediated plastic processes involving long-term potentiation or depression.


Asunto(s)
Hormona Adrenocorticotrópica/sangre , Dopaminérgicos/farmacología , Hipoglucemia/sangre , Memantina/farmacología , Memoria a Corto Plazo/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Glucemia/metabolismo , Epinefrina/sangre , Glucagón/sangre , Técnica de Clampeo de la Glucosa , Hormona del Crecimiento/sangre , Humanos , Hidrocortisona/sangre , Hipoglucemia/inducido químicamente , Hipoglucemia/prevención & control , Potenciación a Largo Plazo , Masculino , Norepinefrina/sangre , Receptores de N-Metil-D-Aspartato/sangre , Prevención Secundaria , Resultado del Tratamiento , Adulto Joven
17.
Am J Transplant ; 12(6): 1429-40, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22420764

RESUMEN

Smooth muscle cells (SMCs) play a key role in the pathogenesis of occlusive vascular diseases, including transplant vasculopathy. Neointimal SMCs in experimental renal transplant vasculopathy are graft-derived. We propose that neointimal SMCs in renal allografts are derived from the vascular media resulting from a transplantation-induced phenotypic switch. We examined the molecular changes in the medial microenvironment that lead to phenotypic modulation of SMCs in rat renal allograft arteries with neointimal lesions. Dark Agouti donor kidneys were transplanted into Wistar Furth recipients and recovered at day 56. Neointimal and medial layers were isolated using laser microdissection. Gene expression was analyzed using low-density arrays and confirmed by immunostaining. In allografts, neointimal SMCs expressed increased levels of Tgf ß1 and Pdgfb. In medial allograft SMCs, gene expression of Ctgf, Tgf ß1 and Pdgfrb was upregulated. Gene expression of Klf4 was upregulated as well, while expression of Sm22α was downregulated. Finally, PDGF-BB-stimulated phenotypically modulated SMCs, as evidenced by reduced contractile function in vitro which was accompanied by increased Klf4 and Col1α1, and reduced α-Sma and Sm22α expression. In transplant vasculopathy, neointimal PDGF-BB induces phenotypic modulation of medial SMCs, through upregulation of KLF4 in the media to contribute to (further) expansion of the neointima.


Asunto(s)
Trasplante de Riñón , Músculo Liso Vascular/citología , Humanos , Inmunohistoquímica , Factor 4 Similar a Kruppel , Fenotipo
18.
Neurosci Biobehav Rev ; 36(7): 1718-28, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22430027

RESUMEN

Extensive research has been accumulated demonstrating that sleep is essential for processes of memory consolidation in adults. In children and infants, a great capacity to learn and to memorize coincides with longer and more intense sleep. Here, we review the available data on the influence of sleep on memory consolidation in healthy children and infants, as well as in children with attention-deficit/hyperactivity disorder (ADHD) as a model of prefrontal impairment, and consider possible mechanisms underlying age-dependent differences. Findings indicate a major role of slow wave sleep (SWS) for processes of memory consolidation during early development. Importantly, longer and deeper SWS during childhood appears to produce a distinctly superior strengthening of hippocampus-dependent declarative memories, but concurrently prevents an immediate benefit from sleep for procedural memories, as typically observed in adults. Studies of ADHD children point toward an essential contribution of prefrontal cortex to the preferential consolidation of declarative memory during SWS. Developmental studies of sleep represent a particularly promising approach for characterizing the supra-ordinate control of memory consolidation during sleep by prefrontal-hippocampal circuitry underlying the encoding of declarative memory.


Asunto(s)
Memoria/fisiología , Fases del Sueño/fisiología , Sueño/fisiología , Animales , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Encéfalo/crecimiento & desarrollo , Preescolar , Humanos , Lactante
19.
Am J Transplant ; 12(3): 660-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22176838

RESUMEN

Local renal complement activation by the donor kidney plays an important role in the pathogenesis of renal injury inherent to kidney transplantation. Contradictory results were reported about the protective effects of the donor C3F allotype on renal allograft outcome. We investigated the influence of the donor C3F allotype on renal transplant outcome, taking all different donor types into account. C3 allotypes of 1265 donor-recipient pairs were determined and divided into four genotypic groups according to the C3F allotype of the donor and the recipient. The four genotypic groups were analyzed for association with primary nonfunction (PNF), delayed graft function, acute rejection, death-censored graft survival and patient survival. Considering all donor types, multivariable analysis found no association of the donor C3F allotype with renal allograft outcome. Also, for living and deceased brain-dead donors, no association with allograft outcome was found. Post hoc subgroup analysis within deceased cardiac dead (DCD) donors revealed an independent protective association of donor C3F allotype with PNF. This study shows that the donor C3F allotype is not associated with renal allograft outcome after kidney transplantation. Subgroup analysis within DCD donors revealed an independent protective association of the donor C3F allotype with PNF, which is preliminary and warrants further validation.


Asunto(s)
Complemento C3/genética , Rechazo de Injerto/genética , Paro Cardíaco , Trasplante de Riñón/mortalidad , Polimorfismo Genético/genética , Donantes de Tejidos , Adulto , ADN/genética , Funcionamiento Retardado del Injerto , Femenino , Genotipo , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Factores de Riesgo , Tasa de Supervivencia , Trasplante Homólogo , Resultado del Tratamiento
20.
Diabetes Obes Metab ; 14(3): 214-21, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21883804

RESUMEN

In recent years, the central nervous system (CNS) has emerged as a principal site of insulin action. This notion is supported by studies in animals relying on intracerebroventricular insulin infusion and by experiments in humans that make use of the intranasal pathway of insulin administration to the brain. Employing neurobehavioural and metabolic measurements as well as functional imaging techniques, these studies have provided insight into a broad range of central and peripheral effects of brain insulin. The present review focuses on CNS effects of insulin administered via the intranasal route on cognition, in particular memory function, and whole-body energy homeostasis including glucose metabolism. Furthermore, evidence is reviewed that suggests a pathophysiological role of impaired brain insulin signaling in obesity and type 2 diabetes, which are hallmarked by peripheral and possibly central nervous insulin resistance, as well as in conditions such as Alzheimer's disease where CNS insulin resistance might contribute to cognitive dysfunction.


Asunto(s)
Encéfalo/efectos de los fármacos , Trastornos del Conocimiento/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/farmacología , Insulina/administración & dosificación , Insulina/farmacología , Obesidad/tratamiento farmacológico , Administración Intranasal , Barrera Hematoencefálica , Encéfalo/metabolismo , Encéfalo/fisiopatología , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/prevención & control , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Humanos , Hipoglucemiantes/administración & dosificación , Resistencia a la Insulina , Masculino , Obesidad/fisiopatología , Receptor de Insulina/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
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