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1.
Neurología (Barc., Ed. impr.) ; 36(6): 403-411, julio-agosto 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-219906

RESUMO

Objetivos: Describir consultas urgentes de pacientes con esclerosis múltiple (EM) distintas a brotes: causas, dificultades diagnósticas, características clínicas y tratamientos empleados.Material y métodosEstudio retrospectivo de los pacientes que acudieron a un Hospital de Día de EM en 2 años por sospecha de brote y que recibieron un diagnóstico alternativo. Se evaluaron variables demográficas, características clínicas de los pacientes, diagnósticos finales y tratamientos. Los pacientes con diagnóstico final de brote e inicialmente diagnosticados de pseudobrote se evaluaron específicamente. Con una finalidad exploratoria se compararon las características de los pacientes que consultaban por causas no inflamatorias con una cohorte de pacientes aleatoriamente seleccionados que habían sufrido un brote en el mismo periodo de tiempo.ResultadosSe incluyeron un total de 50 pacientes inicialmente diagnosticados de pseudobrotes (33 mujeres, con edad media 41,4 ± 11,7 años). Cuatro pacientes (8% del total) fueron inicialmente diagnosticados de pseudobrote aunque posteriormente fueron diagnosticados de un verdadero brote. La fiebre y el vértigo fueron los principales factores de confusión. Las causas no inflamatorias de consulta urgente fueron: neurológicas: 43,5% (20); infecciosas: 15,2% (7); psiquiátricas: 10,9% (5); vértigo: 8,6% (4); traumatológicas: 10,9% (5), y otras: 10,9% (5).ConclusionesLa mayor parte de las consultas urgentes no inflamatorias fueron causadas por síntomas relacionados con la EM. El seguimiento estrecho de brotes y pseudobrotes es necesario para detectar diagnósticos incorrectos, evitar tratamientos innecesarios y aliviar los síntomas de los pacientes. (AU)


Objectives: To describe non-relapse-related emergency consultations of patients with multiple sclerosis (MS): causes, difficulties in the diagnosis, clinical characteristics, and treatments administered.MethodsWe performed a retrospective study of patients who attended a multiple sclerosis day hospital due to suspected relapse and received an alternative diagnosis, over a 2-year period. Demographic data, clinical characteristics, final diagnosis, and treatments administered were evaluated. Patients who were initially diagnosed with pseudo-relapse and ultimately diagnosed with true relapse were evaluated specifically. As an exploratory analysis, patients who consulted with non-inflammatory causes were compared with a randomly selected cohort of patients with true relapses who attended the centre in the same period.ResultsThe study included 50 patients (33 were women; mean age 41.4 ± 11.7 years). Four patients (8%) were initially diagnosed with pseudo-relapse and later diagnosed as having a true relapse. Fever and vertigo were the main confounding factors. The non-inflammatory causes of emergency consultation were: neurological, 43.5% (20 patients); infectious, 15.2% (7); psychiatric, 10.9% (5); vertigo, 8.6% (4); trauma, 10.9% (5); and miscellaneous, 10.9% (5).ConclusionsMS-related symptoms constituted the most frequent cause of non-inflammatory emergency consultations. Close follow-up of relapse and pseudo-relapse is necessary to detect incorrect initial diagnoses, avoid unnecessary treatments, and relieve patients’ symptoms. (AU)


Assuntos
Humanos , Doença Crônica , Esclerose Múltipla/diagnóstico , Encaminhamento e Consulta , Estudos Retrospectivos
2.
Neurologia (Engl Ed) ; 36(6): 403-411, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34238522

RESUMO

OBJECTIVES: To describe non-relapse-related emergency consultations of patients with multiple sclerosis (MS): causes, difficulties in the diagnosis, clinical characteristics, and treatments administered. METHODS: We performed a retrospective study of patients who attended a multiple sclerosis day hospital due to suspected relapse and received an alternative diagnosis, over a 2-year period. Demographic data, clinical characteristics, final diagnosis, and treatments administered were evaluated. Patients who were initially diagnosed with pseudo-relapse and ultimately diagnosed with true relapse were evaluated specifically. As an exploratory analysis, patients who consulted with non-inflammatory causes were compared with a randomly selected cohort of patients with true relapses who attended the centre in the same period. RESULTS: The study included 50 patients (33 were women; mean age 41.4 ±â€¯11.7 years). Four patients (8%) were initially diagnosed with pseudo-relapse and later diagnosed as having a true relapse. Fever and vertigo were the main confounding factors. The non-inflammatory causes of emergency consultation were: neurological, 43.5% (20 patients); infectious, 15.2% (7); psychiatric, 10.9% (5); vertigo, 8.6% (4); trauma, 10.9% (5); and miscellaneous, 10.9% (5). CONCLUSIONS: MS-related symptoms constituted the most frequent cause of non-inflammatory emergency consultations. Close follow-up of relapse and pseudo-relapse is necessary to detect incorrect initial diagnoses, avoid unnecessary treatments, and relieve patients' symptoms.


Assuntos
Esclerose Múltipla , Encaminhamento e Consulta , Adulto , Doença Crônica , Feminino , Humanos , Esclerose Múltipla/diagnóstico , Recidiva , Estudos Retrospectivos
3.
Acta Neurol Scand ; 136(6): 688-693, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28608454

RESUMO

OBJECTIVES: Cardiovascular disease, including myocardial infarction and stroke, is a major cause of mortality in ANCA-associated vasculitis (AAV). Although AAV affects small vessels, an accelerated atherosclerosis not explained by traditional cardiovascular risk factors (CVRF) has been demonstrated. We aimed to investigate the association of atherosclerosis measured by carotid intima-media thickness (CIMT) and cerebral small vessel disease in AAV-patients. MATERIALS & METHODS: Twenty-three AAV-patients in complete remission were recruited. Carotid ultrasonography (US), transcranial Doppler (TCD), brain magnetic resonance imaging (MRI), and SPECT after intravenous administration of tracer 99mTc-HMPAO (dose: 720MBq) were performed. RESULTS: AAV-patients presented higher CIMT compared to normative population. Multivariate linear regression analysis demonstrated an association of higher CIMT with increased pulsatility index in middle cerebral artery (PI-MCA) (P=.011), higher lesion load on ARWMC scale (P=.011) and abnormal SPECT (P=.008). No association between higher CIMT and CVRF (diabetes or hypertension) was demonstrated. Increasing internal carotid artery pulsatility index (PI-ICA) was associated with decreasing mean flow velocity (MFV)-MCA (P=.038), increasing PI-MCA (P=.008) and increasing white matter lesions on MRI (P=.011). CONCLUSIONS: Our study adds weight to the presence of increased atherosclerosis in AAV-patients. The association observed between CIMT and PI-ICA with small vessel cerebral disease, points the possible association of easy to use carotid US in predicting microvascular brain injury.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Aterosclerose/diagnóstico por imagem , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico por imagem , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/epidemiologia , Aterosclerose/epidemiologia , Aterosclerose/etiologia , Artérias Carótidas/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Ultrassonografia
4.
Toxicol In Vitro ; 29(8): 2102-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26277032

RESUMO

Cigarette smoking causes serious and fatal diseases. The best way for smokers to avoid health risks is to quit smoking. Using modified risk tobacco products (MRTPs) may be an alternative to reduce the harm caused for those who are unwilling to quit smoking, but little is known about the toxic effects of MRTPs, nor were the molecular mechanisms of toxicity investigated in detail. The toxicity of an MRTP and the potential molecular mechanisms involved were investigated in high-content screening tests and whole genome transcriptomics analyses using human bronchial epithelial cells. The prototypic (p)MRTP that was tested had less impact than reference cigarette 3R4F on the cellular oxidative stress response and cell death pathways. Higher pMRTP aerosol extract concentrations had impact on pathways associated with the detoxification of xenobiotics and the reduction of oxidative damage. A pMRTP aerosol concentration up to 18 times higher than the 3R4F caused similar perturbation effects in biological networks and led to the perturbation of networks related to cell stress, and proliferation biology. These results may further facilitate the development of a systems toxicology-based impact assessment for use in future risk assessments in line with the 21st century toxicology paradigm, as shown here for an MRTP.


Assuntos
Aerossóis/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Nicotiana , Mucosa Respiratória/citologia , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Brônquios , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , Regulação da Expressão Gênica , Humanos , Transcriptoma
5.
Cerebellum ; 13(1): 178-83, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24068485

RESUMO

Methotrexate (MTX) is considered the main agent for the treatment of rheumatoid arthritis (RA). Neurotoxicity is often mild, but severe encephalopathy can develop, especially with intrathecal or intravenous administration. In rare cases, this syndrome has been observed in patients on long-term low-dose oral administration. A 68-year-old male was diagnosed with RA and on treatment with oral MTX 25 mg weekly for 4 years. The patient started with progressive dysarthria, ataxia and cognitive dysfunction. Complementary tests were normal. Magnetic resonance imaging (MRI) showed hyperintense lesions in both cerebellar hemispheres on T2-weighted and FLAIR images with a diffusion restriction on diffusion-weighted imaging (DWI) and on the apparent diffusion coefficient map (ADC). On postgadolinium T1-weighted images, there were mild enhancements. Spectroscopy showed a demyelinating pattern. A pharmacogenetics determination was made, showing a heterozygous genotype in the MTHFR and ABCB1 genes. Medication with antirheumatic drug was stopped immediately on admission, and the patient gradually improved. MTX-induced leukoencephalopathy can occur even with low-dose administration. The exact pathogenic mechanism is still unknown, but it is hypothesised that it could be the result of a cumulative toxic effect on the blood-brain barrier. The nature of the relationship between the polymorphism and CNS toxicity is still unclear, and thus, further studies are warranted. Often located in the occipital lobes, the involvement of the cerebellum is quite rare. Early recognition of the condition and withdrawal of the drug lead to a better prognosis.


Assuntos
Antirreumáticos/efeitos adversos , Leucoencefalopatias/induzido quimicamente , Metotrexato/efeitos adversos , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Administração Oral , Idoso , Antirreumáticos/administração & dosagem , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Encéfalo/patologia , Doenças Cerebelares/induzido quimicamente , Doenças Cerebelares/patologia , Doenças Cerebelares/fisiopatologia , Cerebelo/patologia , Imagem de Difusão por Ressonância Magnética , Humanos , Leucoencefalopatias/patologia , Leucoencefalopatias/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Metotrexato/administração & dosagem , Metotrexato/uso terapêutico , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética
8.
Cytogenet Genome Res ; 122(3-4): 202-10, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19188688

RESUMO

Telomeres are heterochromatic structures essential for the maintenance of genomic stability and the proliferative potential of human somatic cells. A minimal length of telomeric DNA repeats and proper binding of specialized proteins are required for the maintenance of telomere structure and function. Activation of telomere length maintenance mechanisms is considered a hallmark of cancer, while attrition of telomeres is a known contributor to the phenotypes associated with the aging process. However, the molecular mechanisms responsible for telomere homeostasis are not completely understood. Compelling data indicates that the epigenetic status of telomeric and subtelomeric chromatin also plays a role in the regulation of telomere biology. In addition, genomic regions are not randomly distributed within the nucleus, but rather compartmentalized into spatial and temporal domains whose functional implications for the cell are only beginning to be unraveled. Recent studies indicate that alterations in some of the mechanisms responsible for nuclear organization associate with defects in chromatin structure. These observations suggest a link between these two processes, raising the question of whether nuclear compartmentalization of telomeres might also impact on telomere biology.


Assuntos
Núcleo Celular/fisiologia , Cromatina/fisiologia , Telômero/fisiologia , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Núcleo Celular/genética , Cromatina/genética , DNA/genética , Reparo do DNA , Humanos , Mamíferos/genética , Fenótipo , Proteínas/genética , Sequências Repetitivas de Ácido Nucleico/genética , Transdução de Sinais/fisiologia , Telômero/genética
9.
Artigo em Es | IBECS | ID: ibc-057987

RESUMO

Anteriormente se había observado que el aluminio era capaz de inhibir la síntesis y la secreción de hormona paratiroidea, si bien los mecanismos moleculares subyacentes se desconocían. Estudios recientes han demostrado que dicha inhibición tiene lugar a través de un mecanismo post-transcripcional. Además, el aluminio disminuye la proliferación de las células de la glándula paratiroides de un modo similar al calcio, el principal regulador de la función paratiroidea. Por último, el aluminio es también capaz de activar el receptor-sensor de calcio a concentraciones micromolares, lo que demuestra que éste es el mecanismo por el que las glándulas paratiroides respondían al metal. En conjunto, estos resultados demuestran por primera vez que las acciones del aluminio sobre la función paratiroidea tienen lugar a través de un mecanismo similar al del calcio. Además, dicho efecto es consecuencia de la baja especificidad del receptor-sensor del calcio


Aluminum (Al) is able to inhibit parathyroid hormone (PTH) synthesis and secretion, although the subjacent molecular mechanisms are unknown. Recent studies have shown that this inhibition occurs through a post-transcriptional mechanism. Similarly to calcium, the main regulator of parathyroid function, Al also decreases parathyroid cell proliferation. Finally, Al is also able to activate the calcium-sensing receptor (CaR) at the micromolar level, thus demonstrating that this is the mechanism by which parathyroid glands sense the metal. In summary these results show for the firs time that Al-induced impairment of parathyroid function is a calcium-like mechanism. In addition, this effect is the consequence of a low specificity of the CaR


Assuntos
Humanos , Alumínio/metabolismo , Cálcio/metabolismo , Alumínio/toxicidade , Glândulas Paratireoides/metabolismo , Receptores de Detecção de Cálcio/metabolismo , Insuficiência Renal Crônica/fisiopatologia , Osso e Ossos/metabolismo , Hormônio Paratireóideo/metabolismo
10.
Kidney Int Suppl ; (102): S8-11, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16810310

RESUMO

Parathyroid hyperplasia is the cause of parathyroid gland enlargement in kidney disease (KD). Hypocalcemia, hyperphosphatemia, and vitamin D deficiency are critical contributors to the worsening of the hyperplastic parathyroid growth induced by KD. Reproduction of the features of human KD in the 5/6 nephrectomized rat model has shown that 80% of the mitogenic signals induced by KD in parathyroid cells that are aggravated by either high phosphate (P) or low calcium (Ca) diets occurred within 5 days after the onset of KD. Enhanced parathyroid expression of the potent growth promoter transforming growth factor alpha (TGFalpha) and its receptor, the epidermal growth factor receptor (EGFR), was identified as the main cause of parathyroid hyperplasia in experimental KD. Indeed, administration of highly specific EGFR-tyrosine kinase inhibitors (TKI), which block downstream signaling from TGFalpha-activated EGFR, completely prevented high P- and low Ca-induced parathyroid hyperplasia in early KD, as well as the severe progression of high P-induced parathyroid growth in established secondary hyperparathyroidism, the latter characterized by marked TGFalpha and EGFR overexpression in the parathyroid glands. More importantly, the suppression of signals downstream from TGFalpha binding to EGFR with EGFR-TKI treatment also revealed that TGFalpha self-upregulation in the parathyroid glands is the main determinant of the severity of the hyperplastic growth, and that enhanced TGFalpha activation of EGFR mediates the reduction in parathyroid vitamin D receptor levels thereby causing resistance to both the antiproliferative and parathyroid hormone-suppressive properties of calcitriol therapy.


Assuntos
Regulação da Expressão Gênica , Glândulas Paratireoides/metabolismo , Glândulas Paratireoides/patologia , Transdução de Sinais , Animais , Calcitriol/uso terapêutico , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/metabolismo , Modelos Animais de Doenças , Resistência a Medicamentos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hiperplasia/tratamento farmacológico , Hiperplasia/etiologia , Hiperplasia/metabolismo , Hiperplasia/patologia , Hipocalcemia , Nefropatias/complicações , Nefropatias/tratamento farmacológico , Nefropatias/metabolismo , Nefropatias/patologia , Fósforo na Dieta/administração & dosagem , Fósforo na Dieta/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Vitaminas/uso terapêutico
11.
Nefrologia ; 23 Suppl 2: 7-11, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-12778846

RESUMO

The parathyroid glands have a great sensitivity to small changes in the extracellular ionic calcium. The calcium-sensing receptor (CaR) is a G protein-coupled receptor that responds to extracellular ionic calcium changes activating several intracellular signalling systems (phospholipases C, A2 and D) finally inhibiting the PTH secretion. In addition to calcium, there are some other agonists and modulators such as the Mg2+, spermine, amyloid beta-peptides, a variety of aminoacids, especially aromatic aminoacids and ionic strength. In the uraemia, the sensitivity of the parathyroid glands to calcium is altered and higher values of calcium are necessary to suppress the PTH. In the secondary hyperparathyroidism the CaR expression is reduced. It has been found a negative correlation between cellular proliferation and the expression of the CaR in hyperplasic glands. Despite it is a calcium receptor, the expression of the CaR does not seem to be regulated by calcium and there is some controversy about the role of calcitriol regulating its expression. On the other hand, the phosphorous induces hyperplasia of the parathyroid gland increasing the cellular proliferation and a decrease of the CaR expression.


Assuntos
Cálcio/fisiologia , Hiperparatireoidismo Secundário/fisiopatologia , Falência Renal Crônica/complicações , Glândulas Paratireoides/fisiopatologia , Hormônio Paratireóideo/fisiologia , Receptores de Superfície Celular/fisiologia , Aminoácidos/fisiologia , Peptídeos beta-Amiloides/fisiologia , Animais , Calcitriol/fisiologia , Cálcio/sangue , Sinalização do Cálcio , Humanos , Hipocalcemia/etiologia , Falência Renal Crônica/fisiopatologia , Magnésio/fisiologia , Concentração Osmolar , Fósforo/fisiologia , Ratos , Receptores de Detecção de Cálcio , Transdução de Sinais , Espermina/fisiologia
12.
Nefrologia ; 23 Suppl 2: 27-31, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-12778850

RESUMO

Desferrioxamine and deferiprone are both metal-chelating drugs often used in aluminum-overloaded dialysis patients. In these patients, desferrioxamine produces an improvement on bone mineralisation without a relevant decrease in bone aluminum. Thus, desferrioxamine might have a direct effect on bone cells. The aim of this study was to assess the effect of desferrioxamine and deferiprone on 1,25(OH)2D3-stimulated osteocalcin secretion in osteoblast--like cells. The study was carried out in MG-63 cell cultures. Cells were seeded at a density of 15,000 cel/cm2 and grown to confluence for 72 hours in DMEM supplemented with 10% FCS. The medium was then replaced by another medium containing 1% BSA, 10(-9) M 1,25(OH)2D3 and desferrioxamine 5, 10, 20, 40, 60, 80 microM or deferiprone 15, 30, 60, 120, 180, 240 microM. Tris-HCl at pH 7.4 was used as control. After 48 hours, supernatants were collected for the measurement of secreted osteocalcin. Desferrioxamine and deferiprone, at high doses (desferrioxamine: 60 microM, 80 microM; deferiprone: 180 microM, 240 microM), inhibited the 1,25(OH)2D3-induced osteocalcin secretion. On the contrary, at lower doses (desferrioxamine 5 microM; deferiprone 15 microM) stimulated the secretion. In summary, these results suggest that desferrioxamine and deferiprone exert a direct effect on bone cell metabolism that might be independent from their metal-chelating properties.


Assuntos
Desferroxamina/farmacologia , Osteoblastos/efeitos dos fármacos , Osteocalcina/metabolismo , Piridonas/farmacologia , Alumínio , Animais , Neoplasias Ósseas/patologia , Calcitriol/antagonistas & inibidores , Calcitriol/farmacologia , Bovinos , Quelantes/administração & dosagem , Quelantes/farmacologia , Meios de Cultura/farmacologia , Deferiprona , Desferroxamina/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Osteoblastos/metabolismo , Osteossarcoma/patologia , Piridonas/administração & dosagem , Taxa Secretória/efeitos dos fármacos , Soroalbumina Bovina/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
13.
Nefrología (Madr.) ; 23(supl.2): 7-11, 2003.
Artigo em Espanhol | IBECS | ID: ibc-148517

RESUMO

Las glándulas paratiroides tienen una gran sensibilidad a pequeños cambios en el calcio iónico extracelular. El receptor sensor de calcio (CaR) es un receptor acoplado a proteínas G que es capaz de responder a incrementos en el calcio extracelular activando una serie de señales intracelulares (fosfolipasas C, A2 y D) y cuyo resultado final es la inhibición de la secreción de PTH. Además del calcio, existen otros agonistas y moduladores del CaR como el Mg, espermina, péptidos amilodes β, ciertos aminoácidos, especialmente los aminoácidos aromáticos y la fuerza iónica. En la uremia la sensibilidad de las glándulas paratiroides al calcio está alterada, necesitando concentraciones más altas del mismo para suprimir la PTH. En el hiperparatiroidismo secundario la expresión del CaR se encuentra reducida. En glándulas hiperplásicas se ha observado una correlación negativa entre la proliferación celular y la expresión del CaR. A pesar de ser un receptor de calcio, la expresión del CaR no parece estar regulada por el calcio y existe una cierta discrepancia sobre si el calcitriol es capaz de regular su expresión. Por otro lado, el fósforo provoca una hiperplasia de la glándula paratiroides incrementando la proliferación celular y un descenso en la expresión del CaR (AU)


The parathyroid glands have a great sensitivity to small changes in the extracellular ionic calcium. The calcium-sensing receptor (CaR) is a G protein-coupled receptor that responds to extracellular ionic calcium changes activating several intracellular signaling systems (phospholipases C, A2 and D) finally inhibiting the PTH secretion. In addition to calcium, there are some other agonists and modulators such as the Mg2+, spermine, amyloid β-peptides, a variety of aminoacids, especially aromatic aminoacids and ionic strength. In the uraemia, the sensitivity of the parathyroid glands to calcium is altered and higher values of calcium are necessary to suppress the PTH. In the secondary hyperparathyroidism the CaR expression is reduced. It has been found a negative correlation between cellular proliferation and the expression of the CaR in hyperplasic glands. Despite it is a calcium receptor, the expression of the CaR does not seem to be regulated by calcium and there is some controversy about the role of calcitriol regulating its expression. On the other hand, the phosphorous induces hyperplasia of the parathyroid gland increasing the cellular proliferation and a decrease of the CaR expression (AU)


Assuntos
Humanos , Animais , Ratos , Cálcio/fisiologia , Hiperparatireoidismo Secundário/fisiopatologia , Falência Renal Crônica/complicações , Glândulas Paratireoides/fisiopatologia , Hormônio Paratireóideo/fisiologia , Receptores de Superfície Celular/fisiologia , Aminoácidos/fisiologia , Peptídeos beta-Amiloides/fisiologia , Calcitriol/fisiologia , Cálcio/sangue , Sinalização do Cálcio , Hipocalcemia/etiologia , Falência Renal Crônica/fisiopatologia , Magnésio/fisiologia , Concentração Osmolar , Fósforo/fisiologia , Receptores de Detecção de Cálcio , Transdução de Sinais , Espermina/fisiologia
14.
Nefrología (Madr.) ; 23(supl.2): 27-31, 2003. graf
Artigo em Espanhol | IBECS | ID: ibc-148521

RESUMO

La desferrioxamina y la deferiprona son dos drogas quelantes de metales que se emplean en la sobrecarga alumínica de los pacientes en diálisis. Se ha descrito que la desferrioxamina mejora la mineralización ósea, sin descensos importantes de la concentración de aluminio en hueso. Esto sugiere un efecto directo de la desferrioxamina sobre las células óseas. El objetivo de este trabajo fue evaluar el efecto de desferrioxamina y deferiprona sobre células óseas de estirpe osteoblástica. El estudió se realizó en cultivos de células MG-63. Las células se sembraron a una densidad de 15.000 cel/cm2 y se llevaron a confluencia en un medio DMEM con 10% FCS. Tras 72 horas, se reemplazó el medio por el de ensayo: 1% BSA, 10-9M 1,25(OH)2D3 y desferrioxamina 5, 10, 20, 40, 60, 80 μM o deferiprona 15, 30, 60, 120, 180, 240 μM. Como control se utilizó Tris-HCl a pH 7,4. A las 48 horas se recogieron los sobrenadantes y se midió la osteocalcina secretada. La desferrioxamina y la deferiprona inhibieron la secreción de osteocalcina inducida por vitamina D a concentraciones elevadas (desferrioxamina: 60 μM, 80 μM; deferiprona: 180 μM, 240 μM) mientras que la estimularon a bajas concentraciones (desferrioxamina 5 μM; deferiprona 15 μM). Estos resultados sugieren que tanto la desferrioxamina como la deferiprona son capaces de ejercer un efecto directo sobre el metabolismo del hueso independientemente de su capacidad quelante de metales (AU)


Desferrioxamine and deferiprone are both metal-chelating drugs often used in aluminum-overloaded dialysis patients. In these patients, desferrioxamine produces an improvement on bone mineralisation without a relevant decrease in bone aluminum. Thus, desferrioxamine might have a direct effect on bone cells. The aim of this study was to assess the effect of desferrioxamine and deferiprone on 1,25(OH)2D3-stimulated osteocalcin secretion in osteoblast-like cells. The study was carried out in MG-63 cell cultures. Cells were seeded at a density of 15,000 cel/cm2 and grown to confluence for 72 hours in DMEM supplemented with 10% FCS. The medium was then replaced by another medium containing 1% BSA, 10-9M 1,25(OH)2D3 and desferrioxamine 5, 10, 20, 40, 60, 80 μM or deferiprone 15, 30, 60, 120, 180, 240 μM. Tris-HCl at pH 7.4 was used as control. After 48 hours, supernatants were collected for the measurement of secreted osteocalcin. Desferrioxamine and deferiprone, at high doses (desferrioxamine: 60 μM, 80 μM; deferiprone: 180 μM, 240 μM), inhibited the 1,25(OH)2D3-induced osteocalcin secretion. On the contrary, at lower doses (desferrioxamine 5 μM; deferiprone 15 μM) stimulated the secretion. In summary, these results suggest that desferrioxamine and deferiprone exert a direct effect on bone cell metabolism that might be independent from their metalchelating properties (AU)


Assuntos
Humanos , Animais , Bovinos , Desferroxamina/administração & dosagem , Desferroxamina/farmacologia , Relação Dose-Resposta a Droga , Osteoblastos , Osteoblastos , Osteocalcina , Piridonas/farmacologia , Alumínio , Neoplasias Ósseas/patologia , Calcitriol/antagonistas & inibidores , Calcitriol/farmacologia , Quelantes/administração & dosagem , Quelantes/farmacologia , Meios de Cultura/farmacologia , Osteossarcoma/patologia , Piridonas/administração & dosagem , Taxa Secretória , Células Tumorais Cultivadas , Células Tumorais Cultivadas
15.
Rev. Hosp. Psiquiátr. La Habana ; 23(3): 369-81, jul.-sept. 1982. tab
Artigo em Espanhol | CUMED | ID: cum-13796

RESUMO

Se plantea la hipótesis de que con la aplicación de una variante del sistema de reforzamiento por fichas, podía incrementarse la participación de los pacientes en las actividades desarrolladas en una comunidad terapéutica para psicóticos y alcohólicos, y de que su aplicación era factible dentro de la estructura organizativa mantenida en los tres últimos años de trabajo para lograr estos objetivos se llevó a cabo una investigación desarrollada en tres etapas de tres meses cada una, y se controló durante las mismas el comportamiento de los pacientes en cuanto a: asistencia diaria a la reunión matutina; cumplimiento del horario establecido para levantarse; y otros indicadores utilizados como control por no contemplarse en el sistema de gratificaciones(AU)


Assuntos
Comunidade Terapêutica , Transtornos Psicóticos/terapia , Alcoolismo/terapia
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