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1.
Acta Neurol Scand ; 138(2): 122-129, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29573400

RESUMO

OBJECTIVES: Perampanel is an antiepileptic drug (AED) approved for add-on treatment of focal seizures (with or without generalization) and primary generalized tonic-clonic (GTC) seizures. Our objective was to explore the effectiveness and tolerability of adjunctive perampanel in patients with drug-resistant myoclonic seizures, after failure of other AEDs. MATERIALS AND METHODS: Retrospective, multicenter, observational study. Data were collected from individual patient clinical files and analysed using appropriate descriptive statistics and inferential analyses. RESULTS: Data are reported for 31 patients with mean age 36.4 years, who had an average epilepsy duration of 18 years, previously taken an average of 5.03 AEDs, and were taking an average of 2.4 AEDs on perampanel initiation. Patients exhibited myoclonic, GTC, absence, tonic and focal seizures, and most had associated cognitive decline and/or ataxia. Median time on perampanel was 6 months, most common dose was 6 mg, and overall retention rate was 84%. The responder rate for myoclonic seizures was defined via reduction of days with myoclonic seizures per month. At 6 months, 15 (48.4%) of the 31 patients were classed as myoclonic seizure responders, 10 (32.3%) were myoclonic seizure free, and 39% saw improvements in functional ability. Of 17 patients with GTC seizures at baseline, 9 (53%) were responders at 6 months, and 8 (47.1%) were seizure free. The most frequent side effects were psychiatric disorders, instability, dizziness and irritability, and mostly resolved with dose reduction. Five patients discontinued perampanel due to side effects. CONCLUSIONS: Perampanel caused clinically meaningful improvements in patients with drug-resistant myoclonic seizures. It was generally well tolerated, but psychiatric and neurological side effects sometimes required follow-up and dose reduction.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsias Mioclônicas/tratamento farmacológico , Piridonas/uso terapêutico , Adulto , Idoso , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Estudos Retrospectivos , Convulsões/tratamento farmacológico , Resultado do Tratamento , Adulto Jovem
2.
Epilepsy Behav ; 80: 215-220, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29414555

RESUMO

BACKGROUND: Ring chromosome 20 (R20) syndrome is a chromosomal disorder characterized mainly by drug-resistant frontal lobe seizures, recurrent nonconvulsive status epilepticus (NCSE), and typical EEG features. The aim of this study was to investigate if this triad is common and specific to all patients with R20. METHODS: In this cross-sectional study (from 2000 to 2011), we selected patients who fulfilled at least two out of three criteria: drug-resistant frontal lobe seizures, recurrent NCSE, and characteristic electroencephalography (EEG) features. In all patients, diagnosis was based on karyotype analysis of at least 100 metaphases. RESULTS: We identified 36 patients who met at least two of the selected criteria: six patients (16.7%) with R20 and 30 (83.3%) without R20 (non-R20). All patients with R20 met all three criteria. Eleven (36.7%) patients without R20, however, also displayed the full triad. In 19 patients without R20 (63.3%), one of the three clinical features was missing: frontal lobe seizures were not resistant to antiepileptic drugs (AED) in four (13.3%), recurrent NCSE was missing in six (20%), and nine (30%) patients did not have typical EEG features. Based on this data, specificity was 63.3%, positive predictive value was 35.3%, and sensitivity and negative predictive values were 100%. Additionally, a review of all publications describing the R20 phenotype revealed that 81.98% of patients with R20 display the full electroclinical triad. CONCLUSIONS: In our study, all patients with R20 displayed the three electroclinical characteristics. This is in line with previous reports (presenting high sensitivity and negative predictive value). However, these features can also be observed in other epilepsies and are not specific to R20. Our findings suggest that in the presence of the full triad of symptoms, karyotype analysis focused on chromosome 20 should be conducted.


Assuntos
Transtornos Cromossômicos/genética , Cromossomos Humanos Par 20/genética , Eletroencefalografia , Cromossomos em Anel , Convulsões/diagnóstico , Estado Epiléptico/diagnóstico , Adolescente , Adulto , Criança , Transtornos Cromossômicos/fisiopatologia , Estudos Transversais , Citogenética , Epilepsia/diagnóstico , Epilepsia/genética , Feminino , Lobo Frontal , Humanos , Cariotipagem , Masculino , Valor Preditivo dos Testes , Convulsões/genética , Sensibilidade e Especificidade , Estado Epiléptico/genética
3.
Neurologia ; 31(2): 106-12, 2016 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-24485649

RESUMO

INTRODUCTION: The use of the Multiphasic Personality Inventory Minnesota 2 (MMPI-2) for the diagnosis of psychogenic non-epileptic seizures (PNES) is controversial. This study examines the validity of the clinical scales and, unlike previous works, the content scales. METHODS: Cross-sectional study of 209 patients treated in the epilepsy unit. We performed a logistic regression analysis, taking video-electroencephalography as the reference test, and as predictor variables age, sex, IQ and clinical (model A) or content scales (model B) of the MMPI-2. The models were selected according to the Aikake index and compared using the DeLong test. RESULTS: We analyzed 37 patients with PNES alone, or combined with seizures, and 172 patients with seizures only. The model consisting of sex, Hs (hypochondriasis) and Pa (paranoia) showed a sensitivity of 77.1%, a specificity of 76.8%, a percentage of correct classification of 76.8%, and an area under the curve (AUC) of 0.836 for diagnosing CNEP. Model B, consisting of sex, HEA (health concerns) and FRS (fears), showed a sensitivity of 65.7%, a specificity of 78.0%, a percentage of correct classification of 75.9% and an AUC of 0.840. DeLong's test did not detect significant differences. CONCLUSIONS: The MMPI-2 has a moderate validity for the diagnosis of PNES in patients referred to an epilepsy unit. Using content scales does not significantly improve results from the clinical scales.


Assuntos
MMPI , Convulsões/diagnóstico , Transtornos Somatoformes/diagnóstico , Adulto , Idoso , Estudos Transversais , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Convulsões/psicologia , Transtornos Somatoformes/psicologia , Adulto Jovem
5.
Neurologia (Engl Ed) ; 37(5): 334-345, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35672120

RESUMO

OBJECTIVE: Stereoelectroencephalography (SEEG) is a technique for preoperative evaluation of patients with difficult-to-localise refractory focal epilepsy (DLRFE), enabling the study of deep cortical structures. The procedure, which is increasingly used in international epilepsy centres, has not been fully developed in Spain. We describe our experience with SEEG in the preoperative evaluation of DLRFE. MATERIAL AND METHODS: In the last 8 years, 71 patients with DLRFE were evaluated with SEEG in our epilepsy centre. We prospectively analysed our results in terms of localisation of the epileptogenic zone (EZ), surgical outcomes, and complications associated with the procedure. RESULTS: The median age of the sample was 30 years (range, 4-59 years); 27 patients (38%) were women. Forty-five patients (63.4%) showed no abnormalities on brain MR images. A total of 627 electrodes were implanted (median, 9 electrodes per patient; range, 1-17), and 50% of implantations were multilobar. The EZ was identified in 64 patients (90.1%), and was extratemporal or temporal plus in 66% of the cases. Follow-up was over one year in 55 of the 61 patients undergoing surgery: in the last year of follow-up, 58.2% were seizure-free (Engel Epilepsy Surgery Outcome Scale class I) and 76.4% had good outcomes (Engel I-II). Three patients (4.2%) presented brain haemorrhages. CONCLUSION: SEEG enables localisation of the EZ in patients in whom this was previously impossible, offering better surgical outcomes than other invasive techniques while having a relatively low rate of complications.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Epilepsia , Adolescente , Adulto , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/cirurgia , Eletrodos Implantados , Eletroencefalografia/métodos , Epilepsias Parciais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas Estereotáxicas , Adulto Jovem
6.
Neurologia ; 26(6): 331-6, 2011.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-21345540

RESUMO

BACKGROUND: current diagnostic criteria of probable Creutzfeldt-Jakob disease (CJD) include a combination of clinical, EEG and analytic data. Recent data indicate that brain MRI including fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) sequences can be a valid and reliable tool for the diagnosis of CJD. We describe our experience with high b-value (3000s/mm(2)) diffusion-weighted imaging (DWI) in patients with probable or definite CJD and compare it with standard b-value (1000s/mm(2)) DWI. METHODS: we performed a retrospective analysis of patients admitted to our Hospital Service between 2002 and 2008 with a final diagnosis of probable or definite CJD. Patients were examined using either a 1.5 Tesla or a 3 Tesla MRI. The MRI protocol included T1-weigthed spin-echo sequences, T2-weighted fast spin-echo, FLAIR and DWI sequences with high b-value and standard b-value. RESULTS: during the study period there were 7 patients with probable or definite CJD. Only 3 patients (43%) showed changes on FLAIR sequence consistent with CJD. All the cases were detected with high b-value DWI, including 2 cases (28%) that would have been missed using standard b-value (1000s/mm(2)) DWI. In all the patients the changes were more conspicuous and extensive at high b-value DWI (b=3000s/mm(2)). CONCLUSION: our data indicate that high b-value DWI may improve the sensitivity of brain MRI for the diagnosis of CJD, allowing the detection of some cases that would have been overlooked by conventional sequences.


Assuntos
Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Animais , Encéfalo/patologia , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Rev Neurol ; 73(s03): S01-S07, 2021 12 24.
Artigo em Espanhol | MEDLINE | ID: mdl-34918335

RESUMO

INTRODUCTION: Perampanel (PER) is an antiepileptic drug approved in Europe as add-on therapy for patients with focal onset seizures (with or without secondary generalisation) from the age of 4 years, and for primary generalised tonic-clonic seizures from 7 years of age. OBJECTIVE: Review current evidence on treatment with PER monotherapy after conversion from adjunctive therapy. DEVELOPMENT: Two retrospective multicentre studies in which PER was used as monotherapy show that low doses (6-8 mg/day) of PER were effective and well tolerated in a subgroup of patients with less severe epilepsies than patients who participated in clinical trials (where PER was used as add-on therapy). In these studies, the retention rate exceeded 90% at 3 months, and 70% at 6, and 12 months. The responder rate was > 75% at 3 months, and the rate of seizure-free patients exceeded 50% at 3 and 6 months, and 37% at 12 months. Compared to other observational studies and clinical trials where PER was used as add-on therapy, no adverse effects other than those already known were observed. Four other studies examining the effects of conversion to PER monotherapy in a small number of patients support these results. CONCLUSIONS: In routine clinical practice, conversion to PER monotherapy, at relatively low doses, is an effective and well-tolerated treatment for patients with focal and generalised tonic-clonic seizures.


TITLE: Tratamiento de la epilepsia con perampanel: desde la terapia añadida a la conversión a monoterapia.Introducción.El perampanel (PER) es un fármaco anticrisis epilépticas aprobado en Europa como terapia añadida para pacientes con crisis de inicio focal (con o sin crisis focal a bilateral tonicoclónica) desde los 4 años, y para las crisis tonicoclónicas generalizadas desde los 7 años. Objetivo. Revisar la evidencia existente sobre el tratamiento con PER en conversión a monoterapia. Desarrollo. Dos estudios multicéntricos retrospectivos en los que el PER se convirtió a monoterapia muestran que este fármaco en dosis bajas (6-8 mg/día) fue especialmente eficaz y bien tolerado en un subgrupo de pacientes con epilepsias menos graves que los pacientes que participaron en los ensayos clínicos en donde el PER se empleó como terapia añadida. En estos estudios, la tasa de retención superó el 90% a los tres meses y el 70% a los seis y a los 12 meses. La tasa de respondedores fue > 75% a los tres meses, y la tasa de pacientes libres de crisis llegó a superar el 50% a los tres y a los seis meses, y el 37% a los 12 meses. En comparación con otros estudios donde el PER se empleó como terapia añadida, no se observaron efectos adversos diferentes a los ya conocidos. Otros cuatro estudios que examinaron los efectos del PER en conversión a monoterapia en un número pequeño de pacientes apoyan estos resultados. Conclusiones. En la práctica clínica habitual, el PER es un tratamiento eficaz y bien tolerado cuando se usa en conversión a monoterapia, en dosis relativamente bajas, en pacientes con crisis focales y tonicoclónicas generalizadas.


Assuntos
Epilepsia/tratamento farmacológico , Nitrilas/uso terapêutico , Piridonas/uso terapêutico , Criança , Pré-Escolar , Humanos , Resultado do Tratamento
8.
Sci Rep ; 10(1): 4190, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144343

RESUMO

Epidemiological studies link long term exposure to xenoestrogen Bisphenol-A to adverse cardiovascular effects. Our previous results show that BPA induces hypertension by a mechanism involving CamKII activation and increased redox stress caused by eNOS uncoupling. Recently, CamKII sustained activation has been recognized as a central mediator of programmed cell death in cardiovascular diseases, including necroptosis. However, the role of necroptosis in cardiac response to BPA had not yet been explored. Mice exposed to BPA for 16 weeks showed altered heart function, electrical conduction, and increased blood pressure. Besides, a stress test showed ST-segment depression, indicative of cardiac ischemia. The hearts exhibited cardiac hypertrophy and reduced vascularization, interstitial edema, and large hemorrhagic foci accompanied by fibrinogen deposits. BPA initiated a cardiac inflammatory response, up-regulation of M1 macrophage polarization, and increased oxidative stress, coinciding with the increased expression of CamKII and the necroptotic effector RIP3. In addition, cell death was especially evident in coronary endothelial cells within hemorrhagic areas, and Evans blue extravasation indicated a vascular leak in response to Bisphenol-A. Consistent with the in vivo findings, BPA increased the necroptosis/apoptosis ratio, the expression of RIP3, and CamKII activation in endothelial cells. Necrostatin-1, an inhibitor of necroptosis, alleviated BPA induced cardiac dysfunction and prevented the inflammatory and hemorrhagic response in mice. Mechanistically, silencing of RIP3 reversed BPA-induced necroptosis and CamKII activation in endothelial cells, while inhibition of CamKII activation by KN-93 had no effect on RIP3 expression but decreased necroptotic cell death suggesting that BPA induced necroptosis is mediated by a RIP 3/CamKII dependent pathway. Our results reveal a novel pathogenic role of BPA on the coronary circulation. BPA induces endothelial cell necroptosis, promotes the weakening of coronary vascular wall, which caused internal ventricular hemorrhages, delaying the reparative process and ultimately leading to cardiac dysfunction.


Assuntos
Compostos Benzidrílicos/toxicidade , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Necrose/induzido quimicamente , Fenóis/toxicidade , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Apoptose/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Linhagem Celular , Células Cultivadas , Ecocardiografia , Eletrocardiografia , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Microscopia Confocal , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Necroptose/efeitos dos fármacos , RNA Mensageiro/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais/efeitos dos fármacos
9.
Neurologia (Engl Ed) ; 2019 Jul 20.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31337558

RESUMO

OBJECTIVE: Stereoelectroencephalography (SEEG) is a technique for preoperative evaluation of patients with difficult-to-localise refractory focal epilepsy (DLRFE), enabling the study of deep cortical structures. The procedure, which is increasingly used in international epilepsy centres, has not been fully developed in Spain. We describe our experience with SEEG in the preoperative evaluation of DLRFE. MATERIAL AND METHODS: In the last 8 years, 71 patients with DLRFE were evaluated with SEEG in our epilepsy centre. We prospectively analysed our results in terms of localisation of the epileptogenic zone (EZ), surgical outcomes, and complications associated with the procedure. RESULTS: The median age of the sample was 30 years (range, 4-59 years); 27 patients (38%) were women. Forty-five patients (63.4%) showed no abnormalities on brain MR images. A total of 627 electrodes were implanted (median, 9 electrodes per patient; range, 1-17), and 50% of implantations were multilobar. The EZ was identified in 64 patients (90.1%), and was extratemporal or temporal plus in 66% of the cases. Follow-up was over one year in 55 of the 61 patients undergoing surgery: in the last year of follow-up, 58.2% were seizure-free (Engel Epilepsy Surgery Outcome Scale class I) and 76.4% had good outcomes (Engel I-II). Three patients (4.2%) presented brain haemorrhages. CONCLUSION: SEEG enables localisation of the EZ in patients in whom this was previously impossible, offering better surgical outcomes than other invasive techniques while having a relatively low rate of complications.

10.
BJA Educ ; 23(10): 382-388, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37720556
11.
Emerg Med J ; 23(12): e65, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17130586

RESUMO

A 45-year-old man developed Horner's syndrome after sustaining an intraoral gunshot in a suicide attempt. Examination did not show any major vascular injury or other neurological symptoms. Radiograph of the skull and helical computed tomography angiography of the brain and neck detected a bullet embedded in the interior of the left internal carotid artery (ICA) sheath. Surgical examination showed an intact left ICA. Horner's syndrome resulting from intraoral trauma rarely presents as an isolated sign and is generally associated with carotid injuries. It may herald a life-threatening artery injury and needs urgent investigation.


Assuntos
Síndrome de Horner/etiologia , Boca/lesões , Ferimentos por Arma de Fogo/complicações , Lesões das Artérias Carótidas/complicações , Lesões das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Corpos Estranhos/complicações , Corpos Estranhos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
12.
Biochim Biophys Acta ; 1220(1): 1-14, 1993 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-8268238

RESUMO

We have studied the structure and the function of a truncated human insulin receptor in which 113 amino acids (aa 1231-1343) at the C-terminus of the beta-subunit were deleted. In this study, wild-type and truncated insulin receptors were expressed by stable transfection in NIH-3T3 cells and CHO cells. The mutation impairs post-translational processing of the insulin receptor; proteolytic cleavage is retarded, and degradation of the truncated receptor is accelerated. Furthermore, insulin-stimulated autophosphorylation of the mutant insulin receptor is impaired. This is associated with a defect in insulin-stimulated endocytosis. Finally, in NIH-3T3 cells, the mutant insulin receptor failed to mediate the mitogenic effects of insulin. In CHO cells, transfection of insulin receptor cDNA (either wild-type or mutant) did not alter mitogenic response to insulin. It has previously been shown that deletion of 43 amino acids at the C-terminus of the beta-subunit did not affect insulin receptor tyrosine kinase activity. Our data suggest that the structural domain located 43-113 amino acids from the C-terminus appears to have several functional roles. First, the domain appears to promote folding of receptor into the optimal conformation for post-translational processing. Second, the presence of this domain appears to promote the stability of the receptor beta-subunit in intact cells. Finally, perhaps as a consequence of the effects upon the stability of the receptor, this domain is required in intact cells for insulin-stimulated autophosphorylation and signal transmission.


Assuntos
Endocitose , Processamento de Proteína Pós-Traducional , Receptor de Insulina/metabolismo , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Clonagem Molecular , Cricetinae , DNA , Expressão Gênica , Humanos , Insulina/metabolismo , Camundongos , Dados de Sequência Molecular , Mutação , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fosforilação , Receptor de Insulina/química , Receptor de Insulina/genética , Deleção de Sequência , Timidina/metabolismo , Transfecção
13.
Eur J Intern Med ; 26(4): 268-72, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25770073

RESUMO

BACKGROUND: Adherence to statin therapy has been shown to be suboptimal. In statin-treated patients with residual elevated low density lipoprotein cholesterol (LDL-C) levels the physician must decide whether to switch to a more potent statin or try and achieve better adherence. We examined the association between adherence and LDL-C within low, moderate and high intensity statin groups in a "real world" setting. METHODS: We assessed annual adherence by the mean MPR (Medication Possession Ratio = number of purchased/prescribed daily doses) in unselected patient group. Statins were stratified (ACC/AHA Guideline) into low, moderate and high intensity groups. The impact of adherence on LDL levels was assessed by LOESS (locally weighted scatter plot smoothing). RESULTS: Out of 1183 patients 173 (14.6%) were treated with low, 923 (78.0%) with moderate and 87 (7.4%) with high intensity statins. Statin intensity was inversely associated with adherence (MPR 77±21, 73±22 and 69±21% for low, moderate and high intensity respectively, p=0.018). Non-adjusted LDL levels decreased with higher adherence: a 10% adherence increase resulted in LDL decrease of 3.5, 5.8 and 7.1mg/dL in low, moderate and high intensity groups. Analysis of the adherence effect on LDL levels adjusted for age, DM and ischemic heart disease showed that MPR above 80% was associated with an additional decrease in LDL levels only in the high intensity group. CONCLUSIONS: Increased adherence to statins beyond an MPR of 80% improves LDL levels only among patients given high intensity therapy. Switching from lower to higher intensity therapy may be more effective than further efforts to increase adherence.


Assuntos
LDL-Colesterol/sangue , Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Adesão à Medicação/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Israel , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Resultado do Tratamento
14.
J Invest Dermatol ; 98(6 Suppl): 77S-81S, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1588128

RESUMO

Mutations of the insulin receptor gene have been identified in patients with genetic syndromes of insulin resistance associated with acanthosis nigricans. These mutations impair insulin responses by reducing the number of insulin receptors on the surface of target cells, or by reducing the receptor's ability to bind insulin or to undergo insulin-stimulated autophosphorylation, an important step in insulin action. Studies of mutant receptors expressed in transfection systems have contributed to our understanding of the structure-function relationships of the insulin receptor.


Assuntos
Acantose Nigricans/genética , Resistência à Insulina/genética , Receptor de Insulina/genética , Humanos , Mutação , Síndrome
15.
Endocrinology ; 133(4): 1803-8, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8404622

RESUMO

Covalent attachment of biotin provides a useful method to label cell surface proteins. Subsequent to biotinylation, the protein can be purified by immunoprecipitation with a specific antibody, followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After transfer to a membrane by electroblotting, the biotinylated protein can be detected by probing with labeled streptavidin. This technique has been used to investigate recombinant human insulin receptors expressed on the surface of murine NIH-3T3 cells. Biotinylation of the extracellular domain with an impermeant reagent did not impair the ability of an antibody directed against an epitope in the intracellular domain to immunoprecipitate insulin receptors. In contrast, biotinylation reduced the avidity of a polyclonal antibody directed against the extracellular domain of the receptor. Nevertheless, by increasing the concentration of the antireceptor antibody, it was possible to successfully immunoprecipitate the biotinylated receptor. Furthermore, biotinylated receptors retained the ability to bind insulin and undergo insulin-stimulated autophosphorylation and internalization. The use of enzyme-labeled streptavidin enables the use of chemiluminescence techniques to detect the receptors, thus obviating the need to employ radioactivity. Just as the technique is useful to study cell surface insulin receptors, it can be adapted to investigate other cell surface receptors and proteins.


Assuntos
Proteínas de Bactérias , Biotina , Western Blotting , Endocitose , Proteínas de Membrana/metabolismo , Receptor de Insulina/metabolismo , Células 3T3/metabolismo , Animais , Avidina/farmacologia , Linhagem Celular Transformada , Membrana Celular/metabolismo , Insulina/farmacologia , Camundongos , Fosforilação , Receptor de Insulina/efeitos dos fármacos , Estreptavidina , Transfecção
16.
FEBS Lett ; 341(1): 104-8, 1994 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-8137907

RESUMO

Mutations of the extracellular domain of the insulin receptor impair processing and transport of receptors to the plasma membrane. We have previously reported that a mutation substituting Val for Phe382 in the alpha-subunit of the insulin receptor impairs intracellular processing and insulin-induced autophosphorylation of the mutant receptor. In this investigation, we have generated two independent mutations of amino acids Phe381 and Phe382 of the insulin receptor: Val for Phe381 and Leu for Phe382. These substitutions cause a slight impairment of intracellular processing and transport of the mutant receptors. Furthermore, insulin-dependent internalization of the mutant receptors is unaffected by these mutations. Thus, of the three substitutions studied to date, Val for Phe382 is the only mutation of the Phe381-Phe382 sequence that causes a major defect in post-translational processing of the receptor.


Assuntos
Insulina/metabolismo , Fenilalanina/metabolismo , Processamento de Proteína Pós-Traducional , Receptor de Insulina/metabolismo , Células 3T3 , Animais , Transporte Biológico , Humanos , Ligantes , Camundongos , Mutagênese Sítio-Dirigida , Reação em Cadeia da Polimerase , Receptor de Insulina/biossíntese , Receptor de Insulina/genética , Transfecção
17.
Acta Paediatr Suppl ; 399: 95-104, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7949626

RESUMO

Hormones are secreted by endocrine glands and transported to the target cell at which the hormone acts. The hormone binds to its receptor, thereby eliciting various biological responses within the target cell. Examples of disease mechanisms that function at the different stages in the development of the insulin receptor, and result in insulin resistance, are discussed in this review. Antibodies to insulin can impair delivery of the hormone to the target cell, and can desensitize that target cell to insulin action. In recent years, several genetic diseases have been identified that result from mutations in the genes encoding the relevant receptors. Studies of syndromes of insulin resistance provide illustrations of the multiple types of defects in receptor function that can generally cause hormone resistance (12, 13). For example, mutations in the receptor can decrease the number of receptors on the cell surface by inhibiting receptor biosynthesis, impairing receptor transport to the cell surface, or accelerating the rate of receptor degradation. Alternatively, mutations have been identified that decrease the affinity of insulin binding or inhibit receptor tyrosine kinase activity. In recent years, there has been considerable progress toward elucidating post-receptor mechanisms in the biochemical pathways of hormone action. At present, there are a limited number of examples of mutations in genes encoding proteins that function in this part of the pathway, but it seems likely that additional examples will be discovered in the future. It is likely that these insights into biochemical mechanisms of disease will ultimately lead to an improvement in our ability to treat human disease.


Assuntos
Resistência à Insulina/fisiologia , Doenças Genéticas Inatas/metabolismo , Hormônios/fisiologia , Humanos , Insulina/metabolismo , Mutação , Receptor de Insulina/genética , Receptor de Insulina/imunologia
18.
Gynecol Obstet Fertil ; 28(4): 317-23, 2000 Apr.
Artigo em Francês | MEDLINE | ID: mdl-10859894

RESUMO

Forgetting to take pills is frequent and induces an avoidable risk of unwanted pregnancy. The integration of the daily use of the pill into a ritual allows to improve compliance. Nine hundred and seventy-five women were retrospectively asked by 180 gynecologists about missed pills in the last three and six months. More than nine out of ten women declare having forgotten at least one pill in the last six months. In 39% of the cases the pill was missed during the first week of 'cycle' in which the risk of pregnancy is theoretically increased. In this survey, 485 women used the compliance card for an average time of 3.5 months. The compliance card is a device that reminds the user to take the pill daily. It is the size of a credit card and can be programmed to ring daily at the same time 21 days out of 28. The efficacy of this device is attested by the great number of women who think that it allowed them avoid forgetting at least one pill in the last three months. Regardless of the age of the women, 91% of the users of the compliance card acknowledged that it allowed them to decrease the number of missed pills. Eighty-four percent think avoided forgetting at least one pill in the last three months, 34% between two and three pills and 17% more than three pills. In practice, 41% of the compliance card users didn't have any failure in taking the pill in the last three months versus 19% among nonusers (P = 0.001). Although women aware of their poor compliance more often think that they benefit from the compliance card, 83% of women who declare themselves as compliant share this opinion. The number of avoided missed pills by the compliance card is greater among women who often fail to take their pill. The mean number of missed pill during the three months preceding the use of the compliance card was 1.6 +/- 1.7 versus 0.9 +/- 1.3 during the three months of use. Among users of the compliance card, 98% think that it is easy to use and 97% like the way it works. The compliance card is an easy and reliable device that improves the compliance of women using oral contraceptives by helping them to establish a ritual.


Assuntos
Anticoncepcionais Orais , Memória , Cooperação do Paciente , Adulto , Esquema de Medicação , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Inquéritos e Questionários
19.
Gynecol Obstet Fertil ; 42(3): 155-9, 2014 Mar.
Artigo em Francês | MEDLINE | ID: mdl-24565934

RESUMO

OBJECTIVES: Perineal reeducation of stress urinary incontinence is beneficial in 80% of cases. However, patients have to perform self-retraining exercises of the perineal muscles at home, in order to maintain the benefit of the physiotherapy. The aim of this study is to assess the benefit of GYNEFFIK(®), a perineal electro-stimulator, during this home-care phase. PATIENTS AND METHODS: Women with stress urinary incontinence (UI) or with mixed UI (composed predominantly of stress UI) that responded to physiotherapy were included in this study in two parallel groups. The groups followed a self-reeducation program, with or without GYNEFFIK(®) electro-stimulation sessions. The comparison of the two groups was based on the rate of women for whom the benefit of the initial perineal reeducation was maintained (defined as non-worsening ICIQ and Ditrovie scales' score). RESULTS: According to the protocol, an interim analysis was performed on 95 patients (i.e. almost half of the expected sample size) who had had at least one evaluation under treatment, among which 44 patients had finished the study. The therapeutic benefit of the initial perineal reeducation was maintained in 87.8% of the GYNEFFIK(®) patient group, while it was maintained in 52.2% (P=0.0001) in the usual care group (i.e. who did not use electro-stimulation). DISCUSSION AND CONCLUSION: Likewise, patient had a more favorable subjective impression when using GYNEFFIK(®) (83.7% versus 60.0% in the usual care group) as they felt that they improved during the study. In the GYNEFFIK(®) group, no increase in symptoms was reported, whereas almost one out of five patients in the usual care group felt that their condition had worsened.


Assuntos
Terapia por Estimulação Elétrica , Períneo/fisiopatologia , Incontinência Urinária por Estresse/terapia , Vagina , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Estudos Prospectivos , Resultado do Tratamento , Incontinência Urinária por Estresse/fisiopatologia
20.
J Chromatogr A ; 1370: 171-8, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25454142

RESUMO

Boldenone (Bo), androsta-1,4-dien-17ß-ol-3-one, is an anabolic androgenic steroid not clinically approved for human application. Despite this, many cases are reported every year of athletes testing positive for Bo or its main metabolite 5ß-androst-1-en-17ß-ol-3-one (BoM). Recently the capability of different human intestinal bacteria to produce enzymes able to modify endogenous steroids in Bo has been demonstrated. When a urinary concentration of Bo and/or BoM between 5 and 30 ng/mL is measured a complementary analysis by gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) must be carried out to discriminate the endogenous or exogenous origin. In the present work, a novel analytical method that couples LC-GC by means of the TOTAD interface with C-IRMS is described. The method is based on a first RPLC separation of unacetyled steroids, followed by acetylation and automated on-line LC-GC-C-IRMS, which includes a second RPLC clean-up of acetyl Bo and BoM, isolation of the two fractions in a fraction collector and their consecutive analysis by GC-C-IRMS. The method has been applied to the analysis of urine samples fortified at 5 and 10 ng/mL, where it has shown a good performance.


Assuntos
Anabolizantes/urina , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testosterona/análogos & derivados , Isótopos de Carbono/análise , Dopagem Esportivo , Humanos , Detecção do Abuso de Substâncias/métodos , Testosterona/urina
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