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1.
J Ultrasound Med ; 43(1): 7-19, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37792527

RESUMO

OBJECTIVE: The aim of this study is to determine the accuracy of transvaginal ultrasound (TVU) for the diagnosis of ureteral involvement in women with deep infiltrating endometriosis (DIE). METHODS: The meta-analysis included primary studies comparing the use of TVU for diagnosing endometriotic involvement of the ureter, using laparoscopic surgery and histological diagnosis as the reference standard. Search was performed in several databases (Scopus, Web of Science, and PubMed/MEDLINE). The studies' quality and bias risk were assessed using the Quality Assessment of Diagnostic Accuracy Study-2 (QUADAS-2). Diagnostic performance was estimated by assessing pooled sensitivity and specificity. RESULTS: A total of 496 citations were found. Six articles were ultimately selected for this systematic review and meta-analysis after the inclusion and exclusion criteria were applied. Pooled sensitivity and specificity were 0.81 (95% CI: 0.42-0.96), 1.00 (95% CI: 0.93-1.00). The heterogeneity observed was high for both sensitivity and specificity. Overall risk of bias was low. CONCLUSION: TVU is a valuable tool for the pre-operative identification of ureteral involvement by DIE.


Assuntos
Endometriose , Laparoscopia , Ureter , Feminino , Humanos , Ureter/diagnóstico por imagem , Endometriose/diagnóstico por imagem , Ultrassonografia , Sensibilidade e Especificidade
2.
Transl Stroke Res ; 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37755645

RESUMO

The contribution of excitatory amino acids (AA) to ischemic brain injury has been widely described. In addition, we reported that a mixture of non-excitatory AA at plasmatic concentrations turns irreversible the depression of synaptic transmission caused by hypoxia. Here, we describe that the presence of seven non-excitatory AA (L-alanine, L-glutamine, glycine, L-histidine, L-serine, taurine, and L-threonine) during hypoxia provokes an irreversible neuronal membrane depolarization, after an initial phase of hyperpolarization. The collapse of the membrane potential correlates with a great increase in fiber volley amplitude. Nevertheless, we show that the presence of all seven AA is not necessary to cause the irreversible loss of fEPSP after hypoxia and that the minimal combination of AA able to provoke a solid, replicable effect is the mixture of L-alanine, glycine, L-glutamine, and L-serine. Additionally, L-glutamine seems necessary but insufficient to induce these harmful effects. We also prove that the deleterious effects of the AA mixtures on field potentials during hypoxia depend on both the identity and concentration of the individual AA in the mixture. Furthermore, we find that the accumulation of AA in the whole slice does not determine the outcome caused by the AA mixtures on the synaptic transmission during hypoxia. Finally, results obtained using pharmacological inhibitors and specific substrates of AA transporters suggest that system N and the alanine-serine-cysteine transporter 2 (ASCT2) participate in the non-excitatory AA-mediated deleterious effects during hypoxia. Thus, these AA transporters might represent therapeutical targets for the treatment of brain ischemia.

3.
Neuropharmacology ; 190: 108557, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33848510

RESUMO

The intracellular accumulation of some amino acids (AAs), mainly glutamine, can contribute to brain edema observed during liver failure. We recently demonstrated that individual applications of high concentrations (10 mM) of some non-excitatory AAs increase the electrical resistance of hippocampal slices, indicating cell swelling. Therefore, we pondered whether an AA mixture's application might cause cell swelling at a physiological concentration range. In rat hippocampal slices, we carried out extra- and intracellular electrophysiological recordings and AAs analysis to address this question. We applied a mixture of 19 AAs at their plasmatic concentrations (Plasma solution: Ala, Gly, Gln, His, Ser, Tau, Thr, Arg, Leu, Met, Pro, Val, Asn, Cys, Phe, Ile, Lys, Tyr, and Trp). This solution was afterward divided into two according to the individual AAs at 10 mM concentration inducing synaptic potentiation (Plasma1, containing the first seven AAs of Plasma) or not (Plasma2, with the remaining AAs). Plasma application increased evoked field potentials requiring extracellular chloride. This effect was mimicked by the Plasma1 but not the Plasma2 solution. Plasma1-induced potentiation was independent of changes in release probability, basic electrophysiological membrane properties, and NMDAR activation. AAs in Plasma1 act cooperatively to accumulate intracellularly and to induce synaptic potentiation. In the presence of Plasma1, the reversible synaptic depression caused by a 40-min hypoxia period turned into an irreversible disappearance of synaptic potentials through an NMDAR-dependent mechanism. The presence of a system A transport inhibitor did not block Plasma1-mediated effects. These results indicate that cell swelling, induced by the accumulation of non-excitotoxic AAs through unidentified transporters, might foster deleterious effects produced by hypoxia-ischemia episodes.


Assuntos
Aminoácidos/farmacologia , Edema Encefálico/metabolismo , Potenciais Evocados/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipóxia/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Aminoácidos/metabolismo , Animais , Hipocampo/metabolismo , Potenciação de Longa Duração , Depressão Sináptica de Longo Prazo , Ratos , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica/fisiologia
4.
Amino Acids ; 51(9): 1337-1351, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31428912

RESUMO

The application of high concentrations of taurine induces long-lasting potentiation of synaptic responses and axon excitability. This phenomenon seems to require the contribution of a transport system with a low affinity for taurine. The prototypic taurine transporter TauT (SLC6A6) was discarded by experimental evidence obtained in TauT-KO mice. The purpose of the present study was to determine whether the proton-coupled amino acid transporter 1 (PAT1; SLC36A1) which is a transport system with low affinity and high capacity for a great variety of amino acids including taurine, contributes to the taurine-induced synaptic potentiation. In rat hippocampal slices, the application of several amino acids (L- and D-alanine, L-glutamine, ß-guanidinopropionic acid, glycine, L-histidine, L- and D-serine, sarcosine, L- and D-threonine) imitated the synaptic potentiation induced by taurine. The magnitude of the potentiation caused by some of these amino acids was even greater than that induced by taurine. By contrast, the application of other amino acids (L-arginine, betaine, L-leucine, L-methionine, L- and D-proline, and L-valine) did not induce potentiation. The behaviour of these different amino acids on synaptic potentiation is not compatible with a role of PAT1 in synaptic potentiation. There was a positive correlation between the accumulation of the different amino acids in the slice and the magnitude of synaptic potentiation induced by them. Some of the amino acids inducing synaptic potentiation, like taurine and L-threonine, also increased electrical resistance of the slice, whereas L-leucine did not modify this parameter. Modifications induced by either taurine or L-threonine in synaptic potentiation, slice resistance and amino acid accumulation were dependent on extracellular chloride concentration. These findings support the idea that the accumulation of amino acids throughout the action of transporters causes cell swelling enhancing the electrical resistance of the slice, which by itself could be sufficient to increase field synaptic potentials.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Aminoácidos/metabolismo , Hipocampo/fisiologia , Simportadores/metabolismo , Potenciais Sinápticos , Aminoácidos/química , Aminoácidos/farmacologia , Animais , Impedância Elétrica , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Taurina/metabolismo , Taurina/farmacologia , Treonina/metabolismo , Treonina/farmacologia
5.
Neuropharmacology ; 144: 9-18, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30326239

RESUMO

Recent studies have underscored the importance of the CA2 area in social memory formation. This area, a narrow transition zone between hippocampal CA3 and CA1 areas, is endowed with special connectivity and a distinctive molecular composition. In particular, adenosine A1 receptors (A1R) are enriched in CA2, and based on the prominent synaptic potentiation induced by A1R antagonists (e.g., caffeine) in this area, it has been proposed that CA2 is under the strong tonic control of A1R activation. It is unclear whether this special sensitivity of CA2 to A1R antagonists is due to an elevated extracellular concentration of adenosine or to a different A1R function. Here, using the recording of field potentials evoked simultaneously in CA2 and CA1 by Schaffer collateral stimulation, we confirm that the application of A1R antagonists, caffeine and DPCPX has a stronger effect on synaptic responses in CA2 than in those evoked in CA1. This difference was, at least partially, explained by the action of A1R antagonists on presynaptic A1Rs. We found that caffeine-induced potentiation in CA2 was restricted to Schaffer collateral synapses, but not to those formed by temporoammonic inputs. We also observed that the apparent affinity of an A1R agonist is similar for A1R in both CA2 and CA1 areas, which indicates that the tonic activation of A1R in both areas is comparable. Furthermore, we show that the direct activation of adenylyl cyclase with forskolin in the presence of rolipram, a phosphodiesterase inhibitor, greatly enhances the synaptic potentials in CA2 compared to CA1. The forskolin-induced potentiation was exacerbated in the presence of caffeine or DPCPX, accentuating the differences between the two areas. These results indicate that the tonic activation of A1Rs in area CA2 is not different to that of other hippocampal areas, but it is more efficiently coupled to the downstream effectors.


Assuntos
Região CA2 Hipocampal/efeitos dos fármacos , Antagonistas de Receptores Purinérgicos P1/farmacologia , Adenilil Ciclases/metabolismo , Animais , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Região CA2 Hipocampal/metabolismo , Cafeína/farmacologia , Colforsina/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Masculino , Inibidores de Fosfodiesterase/farmacologia , Agonistas Purinérgicos/farmacologia , Ratos Sprague-Dawley , Receptor A1 de Adenosina/metabolismo , Rolipram/farmacologia , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Técnicas de Cultura de Tecidos , Xantinas/farmacologia
6.
Cir. plást. ibero-latinoam ; 42(3): 241-245, jul.-sept. 2016. ilus
Artigo em Espanhol | IBECS | ID: ibc-157046

RESUMO

Antecedentes y Objetivos. La terapia de vacío es una herramienta adicional en el arsenal terapéutico actual del cirujano plástico y se aplica frecuentemente en el tratamiento de heridas complejas como paso intermedio hasta el tratamiento definitivo de las mismas, y como medida de disminución del tiempo que transcurre hasta su cierre. En el caso de los neonatos, es especialmente crítico conseguir disminuir este tiempo hasta el cierre definitivo de las heridas; sin embargo, la bibliografía al respecto no aporta suficiente información sobre el uso de esta modalidad terapéutica en épocas tempranas de la vida. Pretendemos por tanto compartir la experiencia clínica en este tema de nuestra Unidad de Cirugía Plástica Pediátrica. Material y Método. Describimos 3 casos en los que el uso de terapia de vacío permitió un tratamiento adecuado y definitivo de heridas de diferente etiología y diferentes localizaciones en pacientes neonatos. Conclusiones. Consideramos que la terapia de vacío constituye una excelente herramienta para la preparación de heridas complejas como paso previo al tratamiento definitivo y como una medida terapéutica segura también en neonatos (AU)


Background and Objectives. Vacuum assisted therapy is considered as a valuable tool on the daily practice of plastic surgeons to treat complex injuries as a previous step until the definitive closure is achieved. However, the literature reporting its use on newborn patients is spare, and more research is needed in order to develop well established protocols for its use in this patients. Our objective is to share the clinical experience of our Pediatric Plastic Surgery Unit. Method. We present 3 cases of newborn patients in whom vacuum assisted therapy was highly effective to get a proper and definitive treatment of injuries from different ethology and localization. Conclusions. We consider vacuum assisted therapy as an excellent tool for the preparation of complex wounds as a previous step to the definitive surgical treatment on many patients, including newborns (AU)


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Dispositivos para Expansão de Tecidos , Técnicas de Fechamento de Ferimentos , Tratamento de Ferimentos com Pressão Negativa/métodos , Procedimentos de Cirurgia Plástica/métodos , Desbridamento/métodos , Anormalidades Congênitas/cirurgia , Vácuo
7.
Scand J Psychol ; 57(6): 495-500, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27550188

RESUMO

Overgeneral schemas and lack of autobiographical memory (AM) specificity about our past experiences can predict mood disturbance. Rumination, functional avoidance and executive processes are the main explanatory variables of such overgenerality. However, in non-clinical samples, rumination predicts overgenerality most consistently after the induction of dysphoric mood. Anxiety also activates rumination. Furthermore, anxiety predicts memory performance and has effects on mood which are independent of the effects of rumination. So, what might be the role of anxiety in autobiographical memory performance? A sample of 210 voluntary participants reported measures of autobiographical memory, anxiety, rumination (brooding and reflection), functional avoidance and executive functions (semantic and phonetic verbal fluency task). Autobiographical performance (specificity) was negatively associated with brooding and age and positively with phonetic verbal fluency but not with functional avoidance and anxiety. However, anxiety and brooding were positively correlated even after controlling for depression scores. Moreover, using structural equation modeling, anxiety showed a significant indirect effect on autobiographical specificity through brooding rumination. These results suggest a possible association of anxiety with autobiographical recall through brooding rumination.


Assuntos
Ansiedade , Rememoração Mental , Transtornos de Ansiedade , Função Executiva , Humanos , Memória Episódica
8.
Amino Acids ; 48(11): 2647-2656, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27422547

RESUMO

Taurine is especially abundant in rodent brain where it appears to be involved in osmoregulation and synaptic plasticity mechanisms. The demonstration of a physiological role for taurine has been hampered by the difficulty in modifying taurine levels in most tissues, including the brain. We used an experimental strategy to reduce taurine levels, involving treatment with guanidinoethyl sulfonate (GES), a structural analogue of taurine that, among other properties, acts as a competitive inhibitor of taurine transport. GES delivered in the drinking water of rats for 1 month effectively reduced taurine levels in brain structures (hippocampus, cerebellum and cortex) and outside the brain (heart, muscle, kidney, liver and plasma) by between 50 and 80 %, depending on the tissue. This partial taurine depletion did not affect either basal synaptic transmission or the late phase of long-term potentiation (late-LTP) in hippocampal slices. In vivo microdialysis studies in the hippocampus revealed that GES treatment reduced extracellular taurine levels and the magnitude of taurine released in response to the application of either N-methyl-D-aspartate (NMDA) or a hypoosmotic solution, without affecting release mechanisms. Finally, we demonstrated in hippocampal slices that a brief GES application can mimic taurine action on the conversion of a decremental LTP into a perdurable late-LTP, concluding that GES might replace taurine function in some mechanisms such as those implicated in synaptic plasticity.


Assuntos
Hipocampo/metabolismo , Potenciação de Longa Duração/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Taurina/análogos & derivados , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Taurina/farmacologia
9.
Amino Acids ; 48(5): 1199-208, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26803657

RESUMO

A reduction in taurine content accompanies the ageing process in many tissues. In fact, the decline of brain taurine levels has been associated with cognitive deficits whereas chronic administration of taurine seems to ameliorate age-related deficits such as memory acquisition and retention. In the present study, using rats of three age groups (young, adult and aged) we determined whether the content of taurine and other amino acids (glutamate, serine, glutamine, glycine, alanine and GABA) was altered during ageing in different brain areas (cerebellum, cortex and hippocampus) as well non-brain tissues (heart, kidney, liver and plasma). Moreover, using hippocampal slices we tested whether ageing affects synaptic function and plasticity. These parameters were also determined in aged rats fed with either taurine-devoid or taurine-supplemented diets. With age, we found heterogeneous changes in amino acid content depending on the amino acid type and the tissue. In the case of taurine, its content was reduced in the cerebellum of adult and aged rats, but it remained unchanged in the hippocampus, cortex, heart and liver. The synaptic response amplitude decreased in aged rats, although the late phase of long-term synaptic potentiation (late-LTP), a taurine-dependent process, was not altered. Our study highlights the stability of taurine content in the hippocampus during ageing regardless of whether taurine was present in the diet, which is consistent with the lack of changes detected in late-LTP. These results indicate that the beneficial effects of taurine supplementation might be independent of the replenishment of taurine stores.


Assuntos
Envelhecimento/fisiologia , Hipocampo/fisiologia , Plasticidade Neuronal , Taurina/metabolismo , Fatores Etários , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Encéfalo/fisiologia , Hipocampo/química , Hipocampo/crescimento & desenvolvimento , Fígado/química , Fígado/metabolismo , Potenciação de Longa Duração , Masculino , Ratos , Ratos Sprague-Dawley , Taurina/análise
10.
Clin J Am Soc Nephrol ; 9(5): 897-904, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24578331

RESUMO

BACKGROUND AND OBJECTIVES: Several studies have suggested that activation of the complement system is a contributing pathogenic mechanism in IgA nephropathy (IgAN). C4d staining is an inexpensive and easy-to-perform method for the analysis of renal biopsies. This study aimed to assess the clinical and prognostic implications of C4d staining in IgAN. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This retrospective cohort study included 283 patients with IgAN in 11 hospitals in Spain who underwent a renal biopsy between 1979 and 2010. The primary predictor was mesangial C4d staining. Secondary predictors included demographic, clinical, and laboratory characteristics, and Oxford pathologic classification criteria. The primary end point was the cumulative percentage of patients who developed ESRD, defined as onset of chronic dialysis or renal transplantation. C4d was analyzed by immunohistochemical staining using a polyclonal antibody. Kaplan-Meier and Cox proportional hazards analyses were performed to evaluate the effect of C4d staining on renal survival. RESULTS: There were 109 patients (38.5%) and 174 patients (61.5%) who were classified as C4d positive and C4d negative, respectively. Renal survival at 20 years was 28% in C4d-positive patients versus 85% in C4d-negative patients (P<0.001). Independent risk factors associated with ESRD were as follows: proteinuria (hazard ratio [HR] per every 1 g/d increase. 1.16; 95% confidence interval [95% CI], 1.03 to 1.31; P=0.01), eGFR (HR per every 1 ml/min per 1.73 m(2) increase, 0.96; 95% CI, 0.94 to 0.97; P<0.001), T2 Oxford classification (tubular atrophy/interstitial fibrosis, >50%; HR, 4.42; 95% CI, 1.40 to 13.88; P=0.01), and C4d-positive staining (HR, 2.45; 95% CI, 1.30 to 4.64; P=0.01). CONCLUSIONS: C4d-positive staining is an independent risk factor for the development of ESRD in IgAN. This finding is consistent with the possibility that complement activation is involved in the pathogenesis of this disease.


Assuntos
Complemento C4b/análise , Doença Hepática Terminal/fisiopatologia , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/fisiopatologia , Rim/patologia , Células Mesangiais/química , Fragmentos de Peptídeos/análise , Adulto , Biópsia , Progressão da Doença , Doença Hepática Terminal/etiologia , Doença Hepática Terminal/metabolismo , Doença Hepática Terminal/patologia , Feminino , Taxa de Filtração Glomerular , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/metabolismo , Humanos , Hipertelorismo/complicações , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Rim/química , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteinúria/etiologia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
11.
Rev. enferm. Inst. Mex. Seguro Soc ; 19(3): 155-161, Septiembre-Dic 2011. tab
Artigo em Espanhol | LILACS, BDENF - Enfermagem | ID: biblio-1031157

RESUMO

Resumen


La familia que vive la experiencia de un hijo con cáncer presenta una carga emocional y cambios importantes que requieren de la aceptación de tratamientos rigurosos, necesitan, reorganizar funciones propias del núcleo familiar, y sobre todo fortalecer las relaciones y valores; bajo esta perspectiva, la sociedad actualmente demanda mejor atención por parte del equipo de salud, con un sentid humanista. Por estas razones las enfermeras(os) tienen la responsabilidad de desarrollar conocimientos y habilidades aprendidos y proporcionar los cuidados con profesionalismo, mediante nuevas propuestas o modelos de cuidado. El objetivo principal de la familia, aún no está incorporado en la filosofía del sistema de atención pediátrica. El acercamiento a la familia con situación de un hijo o hija con cáncer es muy importante, entender sus cambios contextuales y reasegurar el ejercicio de la enfermería y la visión y prestigio de la institución por medio del Modelo de “Intervención para Afrontamiento de Familias en Situación de Niño con Cáncer” (AFASINCA).


Summary


The situation of a family in case of a son or daughter with cancer deals with an emotional load and important changes that require the acceptance of rigorous treatments, deal with important demands like material and emotional adjustments, reorganize functions, change roles, strengthen the relation and values; under this perspective, today’s society demand increasingly more and better care with a humanistic sense, in which the professional nurses should have the responsibility of developing knowledge and skills to promote their professionalism, through the creation of new proposals, guides and or ways of care. The main focus in the family is not yet incorporated in the philosophy of care within the pediatric health system. Family approach is very important in the situation of a son or daughter with cancer, understand their contextual changes and to reassure the professional exercises of nursing and the institutions vision through “the model of nursing intervention for the family coping in the situation of a son or daughter with cancer” in which I present in the annexed investigation, AFASINCA Model.


Assuntos
Humanos , Adaptação Psicológica , Assistência Centrada no Paciente , Assistência Hospitalar , Criança , Cuidados de Enfermagem , Enfermagem Oncológica , Enfermagem Pediátrica , Família , Recursos Humanos de Enfermagem Hospitalar , México , Humanos
12.
Interv. psicosoc ; 16(1): 93-105, 2007. tab
Artigo em Es | IBECS | ID: ibc-71103

RESUMO

La atención e intervención con familias es fundamental para realizar programas deintervención eficaces con personas dependientes. Entre otras disciplinas, la psicología ysus profesionales han realizado numerosas contribuciones a nivel teórico y y práctico coneste colectivo. Existen numerosas necesidades de atención y programas de intervenciónpsicológicos con familiares cuidadores. En este artículo se presenta un ejemplo de intervencióncon familiares de personas mayores dependientes


The intervention with families is compulsory in the assistance to people with dependences,all this is important to carry out efficient intervention programs. Among other disciplines,Psychology and its professionals have carried out some contributions in practice andin theory referring to this group of people. All this has to do with assistance needs andpsychological intervention programs. Examples of practical interventions with families of elderly dependent people are shown in this article (AU)


Assuntos
Humanos , Idoso , Pessoas com Deficiência/psicologia , Cuidadores/psicologia , Família/psicologia , Psicoterapia/métodos
13.
J Neurosci ; 26(4): 1077-87, 2006 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-16436593

RESUMO

One of the brain sites more directly related with learning and memory processes is the hippocampus. We recorded, in conscious mice, the activity-dependent changes taking place at the hippocampal CA3-CA1 synapse during the acquisition, extinction, recall, and reconditioning of an associative task. Mice were classically conditioned to evoke eyelid responses using a trace [conditioned stimuli (CS), tone; unconditioned stimuli (US), shock] paradigm. A single electrical pulse presented to the Schaffer collateral-commissural pathway during the CS-US interval evoked a monosynaptic field EPSP (fEPSP) at ipsilateral CA1 pyramidal cells. The slope of evoked fEPSPs increased across conditioning sessions and decreased during extinction, being linearly related to learning evolution. In contrast, fEPSPs were not modified when evoked in control mice in the absence of a conditioning protocol. Long-term potentiation (LTP) evoked by high-frequency stimulation of Schaffer collaterals prevented acquisition, extinction, recall, or reconditioning, depending on the moment when it was triggered. Learning and memory impairments evoked by LTP induction resulted probably from the functional saturation of the CA3-CA1 synapse, although an additional disturbance of the subsequent information transfer toward postsynaptic circuits cannot be discarded. CGP 39551 [(E)-(+/-)-2-amino-4-methyl-5-phosphono-3-pentenoic acid ethyl ester] (an NMDA antagonist) prevented LTP induction in behaving mice, as well as the acquisition of an eyelid learned response, and the synaptic changes taking place at the CA3-CA1 synapse across conditioning. In conclusion, the responsivity of the CA3-CA1 synapse seems to be modulated during associative learning, and both processes are prevented by experimental LTP or NMDA-receptor inactivation. Our results provide evidence of a relationship between activity-dependent synaptic plasticity and associative learning in behaving mice.


Assuntos
Aprendizagem por Associação/fisiologia , Condicionamento Clássico/fisiologia , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Sinapses/fisiologia , 2-Amino-5-fosfonovalerato/análogos & derivados , 2-Amino-5-fosfonovalerato/farmacologia , Estimulação Acústica , Amnésia Anterógrada/fisiopatologia , Amnésia Retrógrada/fisiopatologia , Animais , Piscadela/fisiologia , Eletromiografia , Eletrochoque , Potenciais Pós-Sinápticos Excitadores/fisiologia , Extinção Psicológica/fisiologia , Habituação Psicofisiológica/fisiologia , Deficiências da Aprendizagem/fisiopatologia , Masculino , Rememoração Mental/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células Piramidais/fisiologia , Quinoxalinas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Nervo Trigêmeo/fisiologia
14.
Metab Brain Dis ; 20(4): 265-74, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16382337

RESUMO

Long-term potentiation (LTP) is a long-lasting enhancement of synaptic transmission efficacy and is considered the base for some forms of learning and memory. Hyperammonemia impairs LTP in hippocampus. Proper LTP induction in hippocampal slices requires activation of the soluble guanylate cyclase (sGC)-protein kinase G (PKG)-cyclic guanosine monophosphate (cGMP)-degrading phosphodiesterase pathway. Hyperammonemia impairs LTP by impairing the tetanus-induced activation of this pathway. The tetanus induces a rapid cGMP rise, reaching a maximum at 10 s, both in the absence or in the presence of ammonia. The increase in cGMP is followed, in control slices, by a sustained decrease in cGMP because of PKG-mediated activation of cGMP-degrading phosphodiesterase, which is required for maintenance of LTP. Hyperammonemia prevents completely tetanus-induced decrease in cGMP by impairing PKG-mediated activation of cGMP-degrading phosphodiesterase. Addition of 8 Br-cGMP to slices treated with ammonia restores both phosphodiesterase activation and maintenance of LTP. Impairment of LTP in hyperammonemia may be involved in the impairment of the cognitive function in patients with hepatic encephalopathy.


Assuntos
Hiperamonemia/metabolismo , Hiperamonemia/psicologia , Potenciação de Longa Duração/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , 3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Animais , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Hipocampo/fisiologia , Humanos , Técnicas In Vitro , Potenciação de Longa Duração/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos
15.
J Neurochem ; 94(4): 934-42, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16092938

RESUMO

Long-term potentiation (LTP) is impaired in the CA1 area of hippocampal slices from rats with chronic moderate hyperammonemia. We studied the mechanisms by which hyperammonemia in vivo impairs LTP. This process requires sequential activation of soluble guanylate cyclase, cyclic GMP-dependent protein kinase (PKG) and cyclic GMP-degrading phosphodiesterase. Application of the tetanus induced a rapid increase of cyclic GMP in slices from control or hyperammonemic rats, which is followed in control slices by a sustained decrease in cyclic GMP due to sustained activation of cyclic GMP-degrading phosphodiesterase, which in turn is due to sustained activation of PKG. In slices from rats with chronic hyperammonemia tetanus-induced decrease in cyclic GMP was delayed and transient due to lower and transient activation of PKG and of the phosphodiesterase. Hyperammonemia-induced impairment of LTP may be involved in the alterations of cognitive function in patients with hepatic encephalopathy.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Hipocampo/fisiopatologia , Hiperamonemia/fisiopatologia , Potenciação de Longa Duração , Diester Fosfórico Hidrolases/metabolismo , 3',5'-GMP Cíclico Fosfodiesterases , Animais , Doença Crônica , GMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Estimulação Elétrica , Ativação Enzimática , Hiperamonemia/metabolismo , Técnicas In Vitro , Masculino , Ratos , Ratos Wistar
16.
Artigo em Es | IBECS | ID: ibc-043996

RESUMO

El tratamiento ortopédico prequirúrgico de la fisura palatina es untema controvertido debido a que no está claro si los efectos estéticos son o noduraderos y a que tampoco están claros los efectos que este tratamiento producesobre la futura oclusión. Existen diferentes modalidades de tratamiento.Se presentan dos casos clínicos tratados con la filosofía de Latham


Surgical orthopedic treatment of cleft palate continues to be a controversialtheme due to the fact that it is not clear if it has lasting estheticeffects and to the controversy that exists with regard to its effects on dentalocclusion. There are different treatment modalities. We present two cases treatedwith Latham´s philosophy


Assuntos
Masculino , Lactente , Humanos , Ortodontia/métodos , Fissura Palatina/cirurgia , Estética Dentária , Pinos Dentários , Aparelhos Ortodônticos
17.
Neurochem Int ; 45(6): 895-901, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15312984

RESUMO

Long-term potentiation (LTP) is a long-lasting enhancement of synaptic transmission efficacy and is considered the base for some forms of learning and memory. Nitric oxide (NO)-induced formation of cGMP is involved in hippocampal LTP. We have studied in hippocampal slices the effects of application of a tetanus to induce LTP on cGMP metabolism and the mechanisms by which cGMP modulates LTP. Tetanus application induced a transient rise in cGMP, reaching a maximum at 10s and decreasing below basal levels 5 min after the tetanus, remaining below basal levels after 60 min. Soluble guanylate cyclase (sGC) activity increased 5 min after tetanus and returned to basal levels at 60 min. The decrease in cGMP was due to sustained tetanus-induced increase in cGMP-degrading phosphodiesterase activity, which remained activated 60 min after tetanus. Tetanus-induced activation of PDE and decrease of cGMP were prevented by inhibiting protein kinase G (PKG). This indicates that the initial increase in cGMP activates PKG that phosphorylates (and activates) cGMP-degrading PDE, which, in turn, degrades cGMP. Inhibition of sGC, of PKG or of cGMP-degrading phosphodiesterase impairs LTP, indicating that proper induction of LTP involves transient activation of sGC and increase in cGMP, followed by activation of cGMP-dependent protein kinase, which, in turn, activates cGMP-degrading phosphodiesterase, resulting in long-lasting reduction of cGMP content. Hyperammonemia is the main responsible for the neurological alterations found in liver disease and hepatic encephalopathy, including impaired intellectual function. Hyperammonemia impairs LTP in hippocampus by altering the modulation of this sGC-PKG-cGMP-degrading PDE pathway. Exposure of hippocampal slices to 1 mM ammonia completely prevents tetanus-induced decrease of cGMP by impairing PKG-mediated activation of cGMP-degrading phosphodiesterase. This impairment is responsible for the loss of the maintenance of LTP in hyperammonemia, and may be also involved in the cognitive impairment in patients with hyperammonemia and hepatic encephalopathy.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Hipocampo/efeitos dos fármacos , Hiperamonemia/metabolismo , Potenciação de Longa Duração/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Proteínas Quinases Dependentes de GMP Cíclico/antagonistas & inibidores , Estimulação Elétrica , Ativação Enzimática/fisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Guanilato Ciclase , Encefalopatia Hepática , Humanos , Hiperamonemia/enzimologia , Inibidores de Fosfodiesterase/farmacologia , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Guanilil Ciclase Solúvel
18.
Neurobiol Dis ; 15(1): 1-10, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14751765

RESUMO

Hyperammonemia impairs long-term potentiation (LTP) in hippocampus, by an unknown mechanism. LTP in hippocampal slices requires activation of the soluble guanylate cyclase (sGC)-protein kinase G (PKG)-cGMP-degrading phosphodiesterase pathway. The aim of this work was to assess whether hyperammonemia impairs LTP by impairing the tetanus-induced activation of this pathway. The tetanus induced a rapid cGMP rise, reaching a maximum at 10 s, both in the absence or presence of ammonia. The increase in cGMP is followed in control slices by a sustained decrease in cGMP due to PKG-mediated activation of cGMP-degrading phosphodiesterase, which is required for maintenance of LTP. Hyperammonemia prevents completely tetanus-induced cGMP decrease by impairing PKG-mediated activation of cGMP-degrading phosphodiesterase. Addition of 8Br-cGMP to slices treated with ammonia restores both phosphodiesterase activation and maintenance of LTP. Impairment of LTP in hyperammonemia may be involved in the impairment of the cognitive function in patients with hepatic encephalopathy.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Hipocampo/enzimologia , Hiperamonemia/enzimologia , Potenciação de Longa Duração/fisiologia , Amônia/metabolismo , Amônia/farmacologia , Animais , GMP Cíclico/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Estimulação Elétrica , Guanilato Ciclase , Encefalopatia Hepática/enzimologia , Encefalopatia Hepática/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Hiperamonemia/fisiopatologia , Técnicas In Vitro , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Guanilil Ciclase Solúvel , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
19.
Peu ; 23(2): 82-96, abr. 2003. ilus
Artigo em Es | IBECS | ID: ibc-25668

RESUMO

El presente articulo tiene por objeto establecer los documentos que constituyen el registro de actividades clínicas y se dirige a establecer los contenidos mínimos que deben de constar en la historia clínica, así como a establecer un modelo de la misma orientado al ámbito de las Ciencias Podológicas. (AU)


Assuntos
Anamnese Homeopática , Legislação/normas , Legislação/organização & administração , Prontuários Médicos/normas , Prontuários Médicos/classificação , Prontuários Médicos/legislação & jurisprudência , Anamnese/métodos , Anamnese/normas , Anamnese Homeopática , Legislação/classificação , Legislação/estatística & dados numéricos
20.
Peu ; 23(1): 8-10, ene. 2003. ilus, tab
Artigo em Es | IBECS | ID: ibc-25964

RESUMO

La aparición cada vez más común de neoformaciones cutáneas evolutivas, con desarrollo veloz y crecimiento invasivo (como es el melanoma), proporciona al profesional sanitario y en consecuencia al podólogo la necesidad de permanecer en continua alerta ante cualquier lesión dérmica sospechosa. La necesidad por parte del podólogo de utilizar la inspección como herramienta fundamental dentro de la historia clínica del paciente, hace más frecuente el descubrimiento, muchas veces accidental, de neoformaciones cutáneas malignas. Este artículo pretende concienciar al podólogo con respecto a que, ante cualquier lesión cutánea evolutiva sospechosa, es necesario solicitar pruebas complementarias como por ejemplo la técnica del ganglio centinela, con el fin de obtener un informe oncológico y/o anatomopatológico fundamental antes de tomar cualquier decisión terapéutica (AU)


Assuntos
Pé/patologia , Biópsia , Melanócitos/citologia , Melanócitos/microbiologia , Lentigo/fisiopatologia , Lentigo/patologia , Melanoma/diagnóstico , Melanoma/classificação , Melanoma/terapia , Metástase Neoplásica/patologia , Dermatopatias , Dermatopatias/diagnóstico , Diagnóstico Diferencial , Fatores de Risco , Anamnese/métodos , Melanoma/epidemiologia , Melanoma/fisiopatologia , Melanoma/tratamento farmacológico , Melanoma/radioterapia , Doença Nodular Cutânea/patologia
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