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1.
Encephale ; 36 Suppl 2: D119-23, 2010 Jun.
Artículo en Francés | MEDLINE | ID: mdl-20513454

RESUMEN

CASE-REPORT: We report a case of serotonin syndrome caused by interaction between nasal fentanyl, oxycodone and escitalopram. Due to chronic painful episodes with paroxistic level of pain, a 66-year-old patient, treated for prostate adenocarcinoma and bone metastases received an association of major opiate analgesics (oxycodone 120 mg/day for 6 months, and fentanyl nasal spray four puff of 200 microg/puff). After the addition, for mood disorders, of a small dose of escitalopram (5 mg/day), he developed severe serotoninergic features including diaphoresis, night sweating, tremor, diarrhea, visual disorders with mydriasis and weight loss of 8.8 lbs (4 kg). Discontinuation of escitalopram resulted in complete resolution of his symptoms within 48 h except for persistent blurred vision. DISCUSSION: The clinical manifestations of this case meet Sternbach's criteria of serotonin syndrome. Its possible etiologic factors include adverse drug reaction and pharmacodynamic interaction between selective serotonin reuptake inhibitor (SSRI) antidepressant and opioid analgesics. The Naranjo probability scale suggested a probable causality of escitalopram, oxycodone and fentanyl treatment on the serotonin syndrome. Serotonin syndrome occurrence is estimated around 0.04% in the literature with incidence rates between 14 to 16% in voluntary overdose with serotoninergic agents. It is an infrequent syndrome with, most of the time, a mild to moderate clinical expression. Nevertheless, lethal evolution might occur resulting from either monotherapy with serotoninergic agents (eg: SSRI antidepressants) or the combination of several medications that will increase serotoninergic transmission and therefore intra cerebral serotonin levels. Its physiopathology is related to a hyperstimulation of 5-HT(1A) receptors. Its clinical manifestations involve mental status impairment and cognitive disorders, neuromuscular disorders and neurovegetative impairment. The prescription of SSRI antidepressants among patients depressed, and in pain, exhibiting somatic diseases, and who require regimens of major opiate or related analgesics, is not without risk. CONCLUSION: Clinicians and especially psychiatrists should be aware of possible interaction and the risk of serotonin syndrome when a patient receives a combination of different opioid analgesics and serotonin reuptake inhibitor antidepressants. Improved information and collaboration with somatic and pain specialists and the general practitioners could help reduce the occurrence of this syndrome which can have dreadful consequences. Patients must be informed of such complications, which means that patients should be asked for a history of such events and monitored for serotoninergic adverse events, in order to avoid delays in this diagnosis.


Asunto(s)
Analgésicos Opioides/efectos adversos , Antidepresivos de Segunda Generación/efectos adversos , Citalopram/efectos adversos , Fentanilo/efectos adversos , Oxicodona/efectos adversos , Dolor Intratable/tratamiento farmacológico , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Síndrome de la Serotonina/etiología , Adenocarcinoma/fisiopatología , Adenocarcinoma/psicología , Adenocarcinoma/secundario , Administración Intranasal , Administración Oral , Anciano , Analgésicos Opioides/uso terapéutico , Antidepresivos de Segunda Generación/uso terapéutico , Neoplasias Óseas/fisiopatología , Neoplasias Óseas/psicología , Neoplasias Óseas/secundario , Citalopram/uso terapéutico , Interacciones Farmacológicas , Quimioterapia Combinada , Fentanilo/uso terapéutico , Humanos , Masculino , Oxicodona/uso terapéutico , Dolor Intratable/psicología , Neoplasias de la Próstata/fisiopatología , Neoplasias de la Próstata/psicología , Síndrome de la Serotonina/diagnóstico , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico
2.
Eur J Pain ; 22(7): 1321-1330, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29577519

RESUMEN

BACKGROUND: T-type calcium channels have been shown to play an important role in the initiation and maintenance of neuropathic pain and represent a promising therapeutic target for new analgesic treatments. Ethosuximide (ETX), an anticonvulsant and a T-type channel blocker has shown analgesic effect in several chronic pain models but has not yet been evaluated in patients with neuropathic pain. METHODS: This proof-of-concept, multicentre, double-blind, controlled and randomized trial compared the efficacy and safety of ETX (given as add-on therapy) to an inactive control (IC) in 114 patients with non-diabetic peripheral neuropathic pain. After a 7-day run-in period, eligible patients aged over 18 years were randomly assigned (1:1) to ETX or IC for 6 weeks. The primary outcome was the difference between groups in the pain intensity (% of change from the baseline to end of treatment) assessed in the intention-to-treat population. This study is registered with EudraCT (2013-004801-26) and ClinicalTrials.gov (NCT02100046). RESULTS: The study was stopped during the interim analysis due to the high number of adverse events in the active treatment group. ETX failed to reduce total pain and showed a poor tolerance in comparison to IC. In the per-protocol analysis, ETX significantly reduced pain intensity by 15.6% (95% CI -25.8; -5.4) from baseline compared to IC (-7.8%, 95% CI -14.3; -1.3; p = 0.033), but this result must be interpreted with caution because of a small subgroup of patients. CONCLUSION: Ethosuximide did not reduce the severity of neuropathic pain and induces, at the doses used, many adverse events. SIGNIFICANCE: This article shows that ETX is not effective to treat neuropathic pain. Nevertheless, per-protocol analysis suggests a possible analgesic effect of ETX. Thus, our work adds significant knowledge to preclinical and clinical data on the benefits of T-type calcium channel inhibition for the treatment of neuropathic pain.


Asunto(s)
Bloqueadores de los Canales de Calcio/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Etosuximida/uso terapéutico , Neuralgia/tratamiento farmacológico , Adulto , Anciano , Analgésicos/uso terapéutico , Anticonvulsivantes/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prueba de Estudio Conceptual
3.
J Clin Invest ; 94(5): 2068-76, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7962553

RESUMEN

Clonal expansion of T cell specificities in the synovial fluid of patients has been taken as evidence for a local stimulation of T cells. By studying the T cell receptor (TCR) repertoire of CD4+ T cells in the synovial and peripheral blood compartments of patients with early rheumatoid arthritis (RA), we have identified clonally expanded CD4+ populations. Expanded clonotypes were present in the peripheral blood and the synovial fluid but were not preferentially accumulated in the joint. Dominant single clonotypes could not be isolated from CD4+ cells of HLA-DRB1*04+ normal individuals. Clonal expansion involved several distinct clonotypes with a preference for V beta 3+, V beta 14+, and V beta 17+CD4+ T cells. A fraction of clonally related T cells expressed IL-2 receptors, indicating recent activation. The frequencies of clonally expanded V beta 17+CD4+ T cells fluctuated widely over a period of one year. Independent variations in the frequencies of two distinct clonotypes in the same patient indicated that different mechanisms, and not stimulation by a single arthritogenic antigen, were involved in clonal proliferation. These data support the concept that RA patients have a grossly imbalanced TCR repertoire. Clonal expansion may result from intrinsic defects in T cell generation and regulation. The dominance of expanded clonotypes in the periphery emphasizes the systemic nature of RA and suggests that T cell proliferation occurs outside of the joint.


Asunto(s)
Artritis Reumatoide/inmunología , Linfocitos T CD4-Positivos/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Secuencia de Aminoácidos , Secuencia de Bases , Antígenos HLA-DR/análisis , Humanos , Datos de Secuencia Molecular , Receptores de Interleucina-2/análisis , Líquido Sinovial/inmunología
4.
Environ Pollut ; 148(3): 855-66, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17478020

RESUMEN

The soil compartment is an important interface between the atmosphere and the subsurface hydrosphere. In this paper a conceptual approach for regional hydrologic soil modelling (RHSM) is presented, which provides two important qualities for modelling. First, the soil compartment is directly coupled to the atmosphere via the land surface and to the aquifers. Second, extremely fine (5cm vertical) resolutions of the soil system can be realized at regional scales (several hundreds of km(2)). This high-resolution modelling could be achieved by parallel computation techniques. The RHSM approach is applied to the Beerze-Reusel drainage basin, which belongs to the Meuse River basin. Moisture transport in the soil system was calculated with extremely high vertical resolution at a regional scale based on rainfall-evaporation data for the year 2000. As a result, highly resolved regional groundwater recharge pattern addressing the heterogeneity of soil systems could be determined.


Asunto(s)
Modelos Teóricos , Suelo , Movimientos del Agua , Abastecimiento de Agua
5.
Sci Total Environ ; 376(1-3): 40-50, 2007 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-17307233

RESUMEN

Deposition, turnover and movement of persistent organic pollutants (POP) were investigated in the EU integrated project "AquaTerra", which is among the first funded environmental projects within the 6th Framework Program by the European Commission. Project work integrates across various disciplines that range from biogeochemistry, environmental engineering, computer modelling and chemistry to socio-economic sciences. Field study areas are the river basins of the Ebro, the Meuse, the Elbe and the Danube as well as the 3-km(2) French catchment of the Brévilles Spring. Within the first 2 years of the project more than 1700 samples of atmospherically deposited particles, sediments, and water have been collected in the above-mentioned systems. Results show clear spatial patterns of deposition of polyaromatic hydrocarbons (PAHs) with the highest rates in the Meuse Basin. For local inputs, in the Brévilles sandy aquifer, the contamination of the groundwater by the pesticides atrazine (AT) and deethylatrazine did not decrease even 5 years after their agricultural inputs were stopped. On the other hand, herbicides such as mecroprop (MCPP), and PAHs, were at least partially degraded microbiologically in laboratory studies with soils and aquifer material from selected sites. For sediment transport of contaminants, new flood sampling techniques revealed highest deposition rates of beta-hexachlorocyclohexane (beta-HCH) in river sediments at hotspot areas on the Mulde River in the Bitterfeld region (Elbe Basin, Germany). These selected preliminary results of AquaTerra help to improve fundamental understanding of persistent organic pollutants (POP) in the environment.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminantes Químicos del Agua/análisis , Atrazina/análogos & derivados , Atrazina/análisis , Monitoreo del Ambiente , Unión Europea , Francia , Sedimentos Geológicos/análisis , Alemania , Herbicidas/análisis , Hexaclorociclohexano/análisis , Insecticidas/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Ríos/química , Triazinas/análisis , Abastecimiento de Agua/análisis
6.
J Bone Miner Res ; 13(12): 1909-14, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9844109

RESUMEN

Severe idiopathic osteoporosis in middle-aged men is still poorly understood. The aim of this study was to assess the contribution of genetic factors in these patients. We studied 38 men (mean age +/- SD, 50 +/- 11 years) presenting with vertebral or peripheral bone fractures due to primary osteoporosis and 73 of their relatives divided into four subgroups: 19 brothers, 22 sisters, 13 sons, and 19 daughters. The control group comprised 199 age-matched subjects. In all subjects, we measured bone mineral density (BMD) and calculated the Z score at the lumbar spine (LS) and femoral neck (FN) based on the fitted BMD value in the controls. LS BMD values were lower in each of the four subgroups compared with the age-matched controls. The mean Z score for the overall group of 73 relatives was decreased compared with the age-matched controls (-1. 28 +/- 1.48 at the LS and -1.03 +/- 1.19 at the FN) and was not influenced by gender or by whether the relatives were siblings or children. An LS Z score < -1) was found in 54.8% of the relatives of osteoporotic patients versus 17.4% of the control subjects (risk ratio, 3.2). Alcohol and tobacco abuse are well-known risk factors for osteoporosis in men. Among the 38 osteoporotic patients, 7 were heavy smokers (>20 pack-years), 8 were both heavy smokers and drinkers (>80 g/day for at least 10 years and gammaGT > 40 UI/l), and 23 had neither of these risk factors. BMD, Z score, and anthropometric data were the same in patients with and without risk factors. Decreases in LS and FN Z scores were similar in relatives of patients with and without risk factors. In conclusion, low BMD is observed in relatives of osteoporotic men with or without risk factors for osteoporosis, indicating that familial factors contribute to primary osteoporosis in middle-aged men.


Asunto(s)
Densidad Ósea/genética , Osteoporosis/genética , Osteoporosis/patología , Absorciometría de Fotón , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/efectos adversos , Femenino , Cuello Femoral/patología , Humanos , Vértebras Lumbares/lesiones , Vértebras Lumbares/patología , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/genética , Fracturas de la Columna Vertebral/patología , Encuestas y Cuestionarios , Población Blanca
7.
J Bone Miner Res ; 5 Suppl 1: S191-4, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2339628

RESUMEN

We report clinical and bone morphometric findings in 18 osteoporotic patients who experienced stress fractures during fluoride therapy. Patients were treated with either sodium fluoride (n = 15), or sodium monofluorophosphate (n = 3). Oral calcium supplementation was given in 11 patients, and vitamin D in 13. Stress fractures occurred after 17.1 +/- 10.3 months of therapy (range: 5-41 months). Atraumatic sudden pain in a lower limb bone extremity, normal initial roentgenogram, high 99technetium uptake on early bone scan, and a 3 to 4 week delay in linear bone condensation area at the same site were characteristics of stress fracture. The most frequent sites were the tibial metaphysis (n = 13), femoral neck (n = 10), and calcaneus (n = 4). Biochemical data showed increased plasma alkaline phosphatase levels in 11 patients, and mild renal failure in 2. Bone histomorphometry was performed on an iliac crest specimen in 10 patients at the time of the stress fracture. Trabecular bone volume was normal, and formation parameters were increased. Features of osteomalacia were encountered in only 2 patients with decreased renal function. Trabecular resorption was increased, as assessed by the osteoclastic surface (1.01 +/- 1.15% bone surface), and the number of osteoclasts (0.44 +/- 0.49 per mm2 bone section). The clinical course was favorable in all patients who stopped fluoride, although 5 patients who continued the treatment had either completion of femoral neck stress fractures to hip fractures (n = 2), or recurrent stress fractures (n = 2), or both (n = 1). Fluoride appears to be a key factor in the pathogenesis of stress fractures, and may be associated with increased trabecular resorption in some treated patients.


Asunto(s)
Fluoruros/efectos adversos , Fracturas por Estrés/inducido químicamente , Traumatismos de la Pierna/etiología , Osteoporosis/tratamiento farmacológico , Fosfatos/efectos adversos , Fluoruro de Sodio/efectos adversos , Anciano , Anciano de 80 o más Años , Femenino , Fluoruros/uso terapéutico , Fracturas por Estrés/diagnóstico por imagen , Humanos , Traumatismos de la Pierna/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Osteoporosis/diagnóstico por imagen , Fosfatos/uso terapéutico , Radiografía , Fluoruro de Sodio/uso terapéutico
8.
J Bone Miner Res ; 10(2): 307-14, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7754812

RESUMEN

Local mediators of bone resorption may be involved in bone loss in recently postmenopausal women and in osteoporosis. In the present study, we investigated the production of cytokines and the formation of osteoclast-like cells in marrow cultures from 16 late postmenopausal nonosteoporotic women (mean age: 66 +/- 8 years; time after menopause: 15 +/- 8 years) undergoing hip replacement for arthrosis. Marrow adherent mononuclear cells (MMNC) isolated from femoral diaphysis marrow were cultured for 10 days in the absence or in the presence of 1,25(OH)2D3. In vivo bone resorption was concomitantly assessed by histomorphometry on femoral neck bone sections. The number of TRAP+ multinucleated cells obtained after 10 days in MMNC cultured in the presence of 1,25(OH)2D3 correlated with the number of osteoclasts measured on the bone femoral neck biopsies (r = 0.65, p < 0.01), suggesting that the formation of multinucleated cells in vitro could reflect the osteoclast differentiation in vivo. Furthermore, the number of osteoclasts was related to the eroded volume and the trabecular separation of the femoral neck bone biopsies. Finally, the release of interleukin-1 (IL-1), IL-6, and TNF-alpha by cultures of peripheral blood mononuclear cells (PBMC) and MMNC was measured by radioimmunoassay. The cytokine levels of basal and 1,25(OH)2D3-treated MMNC decreased from days 2 to 5 and then reached a plateau to day 10. The number of TRAP+ multinucleated cells obtained after 10 days in MMNC cultures correlated with the basal IL-6 release in the same cultures determined at day 2 (r = 0.55, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Densidad Ósea/fisiología , Resorción Ósea/fisiopatología , Citocinas/biosíntesis , Cuello Femoral/patología , Leucocitos Mononucleares/metabolismo , Posmenopausia , Absorciometría de Fotón , Anciano , Análisis de Varianza , Artritis/cirugía , Células de la Médula Ósea , Calcitriol/farmacología , Células Cultivadas , Femenino , Cuello Femoral/citología , Prótesis de Cadera , Humanos , Interleucina-1/biosíntesis , Interleucina-6/biosíntesis , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Persona de Mediana Edad , Osteoclastos/citología , Osteoclastos/fisiología , Posmenopausia/fisiología , Radioinmunoensayo , Factor de Necrosis Tumoral alfa/biosíntesis
9.
Medicine (Baltimore) ; 78(5): 309-20, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10499072

RESUMEN

Spinal tuberculosis (TB) accounts for about 2% of all cases of TB. New methods of diagnosis such as magnetic resonance imaging (MRI) or percutaneous needle biopsy have emerged. Two distinct patterns of spinal TB can be identified, the classic form, called spondylodiscitis (SPD) in this article, and an increasingly common atypical form characterized by spondylitis without disk involvement (SPwD). We conducted a retrospective study of patients with spinal TB managed in the area of Paris, France, between 1980 and 1994 with the goal of defining the characteristics of spinal TB and comparing SPD to SPwD. The 103 consecutive patients included in our study had TB confirmed by bacteriologic and/or histologic studies of specimens from spinal or paraspinal lesions (93 patients) or from extraspinal skeletal lesions (10 patients). Sixty-eight percent of patients were foreign-born subjects from developing countries. None of our patients was HIV-positive. SPD accounted for 48% of cases and SPwD for 52%. Patients with SPwD were younger and more likely to be foreign-born and to have multiple skeletal TB lesions. Neurologic manifestations were observed in 50% of patients, with no differences between the SPD and SPwD groups. Of the 44 patients investigated by MRI, 6 had normal plain radiographs; MRI was consistently positive and demonstrated epidural involvement in 77% of cases. Bacteriologic and histologic yields were similar for surgical biopsy (n = 16) and for percutaneous needle aspiration and/or biopsy (n = 77). Cultures for Mycobacterium tuberculosis were positive in 83% of patients, and no strains were resistant to rifampin. Median duration of antituberculous chemotherapy was 14 months. Surgical treatment was performed in 24% of patients. There were 2 TB-related deaths. Our data suggest that SPwD may now be the most common pattern of spinal TB in foreign-born subjects in industrialized countries. The reasons for this remain to be elucidated.


Asunto(s)
Tuberculosis de la Columna Vertebral/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Antibióticos Antituberculosos/uso terapéutico , Biopsia con Aguja , Causas de Muerte , Países Desarrollados/estadística & datos numéricos , Países en Desarrollo/estadística & datos numéricos , Discitis/epidemiología , Discitis/microbiología , Emigración e Inmigración/estadística & datos numéricos , Femenino , Francia/epidemiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/aislamiento & purificación , Paris/epidemiología , Estudios Retrospectivos , Rifampin/uso terapéutico , Espondilitis/epidemiología , Espondilitis/microbiología , Tuberculosis Osteoarticular/epidemiología , Tuberculosis de la Columna Vertebral/tratamiento farmacológico , Tuberculosis de la Columna Vertebral/cirugía
10.
Bone ; 8(6): 339-42, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3449108

RESUMEN

We studied sequential bone biopsies performed at 6 to 24 month intervals from 14 untreated osteoporotic women (64 +/- 7). Subgroups were defined, respectively, by increased osteoclastic resorption surfaces and decreased osteoblastic surfaces +/- 2 S.D. Normal values were obtained from bone biopsy of 23 normal women (61 +/- 8). When patients were divided into subgroups according to the above criteria the first biopsy showed that 3 out of the 14 patients had high resorption surfaces and 6 had low osteoblastic surfaces. Eight patients spontaneously changed during the study. In 2 patients there was a change in resorption surfaces, in 3 in osteoblastic surfaces and in 3 a change in both osteoblastic and resorption surfaces was observed. Considering the first or second bone biopsy results the patient variance was higher than the control subject's variance; however the variance between the first and second bone biopsy of one patient was not different from the variance inside the group of patients. The average intraindividual variation of the parameters on sequential biopsies was of the same order as the one we previously observed on simultaneous bone biopsies of normal and hemodialyzed patients. We concluded that if osteoporosis is a heterogeneous disorder, subgroups cannot be definitively defined on the basis of cellular parameters of bone remodelling assessed on bone biopsies.


Asunto(s)
Huesos/patología , Menopausia/metabolismo , Osteoporosis/patología , Anciano , Biopsia , Resorción Ósea/patología , Femenino , Humanos , Persona de Mediana Edad
11.
Biochimie ; 74(2): 137-41, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1581389

RESUMEN

The cloned T brucei GAPDH gene was inserted within the B subtilis GAPDH gene, carried by pUC18. Upon transformation of B subtilis by this plasmid, not able to replicate in this host, the whole plasmid was inserted in the resident chromosome, presumably by a single recombination event between homologous, chromosomal and plasmid-borne sequences. The heterologous gene was expressed, as revealed by immunological reaction with monoclonal antibodies, recognizing specifically T brucei GAPDH. T brucei GAPDH, having little or no enzyme activity, comprises about 1.56% of cellular proteins. Peptide mapping showed that a fusion of a 7.5-kDa peptide had occurred to the N-terminal part of T brucei GAPDH. This fused protein is presumably the N-terminal part of B subtilis GAPDH, in agreement with the construction of the integrative plasmid.


Asunto(s)
Bacillus subtilis/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Trypanosoma brucei brucei/genética , Animales , Anticuerpos Monoclonales , Bacillus subtilis/enzimología , Western Blotting , Clonación Molecular , Expresión Génica , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Immunoblotting , Técnicas para Inmunoenzimas , Mapeo Peptídico , Plásmidos , Proteínas Recombinantes/metabolismo , Transformación Bacteriana , Trypanosoma brucei brucei/enzimología
12.
Am J Med ; 99(3): 243-8, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7653483

RESUMEN

PURPOSE: Patients treated by long-term maintenance hemodialysis frequently develop a form of chronic arthropathy that is strongly associated with beta 2-microglobulin amyloid deposition and related, at least in part, to beta 2-microglobulin retention. Successful renal transplantation is followed by a rapid fall in serum beta 2-microglobulin levels and might allow dissolution of amyloid deposits. The purpose of this work was to investigate the effects of renal transplantation on dialysis arthropathy. PATIENTS AND METHODS: Fourteen renal transplant recipients were selected on the basis of previous hemodialysis treatment for at least 10 years (mean 16) and a history of chronic joint pain prior to transplantation. They all received 10 to 17.5 mg/d of prednisone. Posttransplant rheumatologic manifestations were studied prospectively and compared to pretransplant rheumatologic manifestations recorded in medical charts and reported during patient interviews. Pretransplant and posttransplant articular roentgenograms were separately analyzed by three observers who were blinded to timing of the films. Beta 2-microglobulin amyloid was identified by Congo red staining and immunohistology. RESULTS: After a mean posttransplant interval of 54 months (range 12 to 121), the articular condition was improved in 10 patients, unchanged in 1, and worsened in 3, according to patients' assessments. The number of painful joints decreased significantly (P < 0.05) as compared to the pretransplant period. However, the number and size of subchondral bone erosions remained unchanged, destructive arthropathies generally worsened, and articular beta 2-microglobulin amyloid deposits were identified in 2 patients, 2 and 10 years after renal transplantation, respectively. CONCLUSION: Renal transplantation appeared to arrest progression of beta 2-microglobulin amyloid in dialysis patients, but it neither led to dissolution of deposits nor prevented progression of destructive arthropathies. Most articular symptoms were improved, probably as a result of corticosteroid therapy.


Asunto(s)
Amiloidosis/etiología , Artralgia/etiología , Trasplante de Riñón , Diálisis Renal/efectos adversos , Microglobulina beta-2/metabolismo , Adulto , Amiloidosis/diagnóstico por imagen , Amiloidosis/metabolismo , Artralgia/diagnóstico por imagen , Artralgia/metabolismo , Rojo Congo , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radiografía
13.
Mol Biochem Parasitol ; 47(1): 1-9, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1857377

RESUMEN

The kinetic properties of aldolase from Trypanosoma brucei were studied in comparison with aldolase from rabbit muscle and Staphylococcus aureus. The 3 enzymes displayed a similar broad pH optimum for the cleavage of fructose 1,6-bisphosphate (Fru(1,6)P2) and a similar narrow pH optimum for the cleavage of fructose 1-phosphate (Fru-1-P). However, small alterations in the maximal cleavage rate at more extreme pH values yielded disparities between the pH curves. The reaction catalyzed by the aldolases from T. brucei and S. aureus proceeded via an ordered sequence, as described for the rabbit-muscle enzyme. We determined for the 3 enzymes the kinetic parameters for both the cleavage and the formation of Fru(1,6)P2 and for the cleavage of Fru-1-P. The trypanosomal enzyme differed in its higher ratio of the maximal rate of Fru(1,6)P2-cleavage vs. the maximal rate of Fru(1,6)P2-formation, its higher affinity towards dihydroxyacetone phosphate, and its higher turnover number for the cleavage of Fru-1-P. At ionic strengths above 0.1 M the kinetic parameters of the trypanosomal enzyme followed the limited form of the Debye-Hückel equation. At ionic strengths below 0.1 M the enzyme revealed a characteristic deviation: the apparent Km for Fru(1,6)P2 increased with decreasing salt concentration. The trypanosomal aldolase was competitively inhibited by adenine nucleotides and phosphates. This inhibition occurred in the same concentration range as observed for the rabbit-muscle enzyme, while the bacterial enzyme was less affected.


Asunto(s)
Proteínas Bacterianas/metabolismo , Fructosa-Bifosfato Aldolasa/metabolismo , Músculos/enzimología , Staphylococcus aureus/enzimología , Trypanosoma brucei brucei/enzimología , Adenosina Difosfato/farmacología , Adenosina Monofosfato/farmacología , Adenosina Trifosfato/farmacología , Animales , Proteínas Bacterianas/antagonistas & inhibidores , Fructosa-Bifosfato Aldolasa/antagonistas & inhibidores , Fructosadifosfatos/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Músculos/efectos de los fármacos , Concentración Osmolar , Fosfatos/farmacología , Conejos , Staphylococcus aureus/efectos de los fármacos , Termodinámica , Trypanosoma brucei brucei/efectos de los fármacos
14.
Mol Biochem Parasitol ; 47(1): 19-29, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1857383

RESUMEN

Pyruvate kinase from Trypanosoma brucei is a labile enzyme, losing its activity within several hours. In mixtures containing 50 mM triethanolamine buffer, pH 7.2, 25% glycerol and 0.5 mM inorganic phosphate the enzyme remained active and could be purified to homogeneity with a specific activity of 417 units mg-1 and a yield of 65%. The enzyme has an activation energy of 31.9 kJ mol-1. Magnesium and potassium ions are essential for activity. Cobalt or manganese ions replace Mg2+ but this leads to a decrease in maximal velocity. Potassium ions can be substituted by ammonium ions, while sodium ions behave as a competitive inhibitor with respect to both K+ and NH4+. All metal ions studied displayed sigmoidal kinetics. The enzyme is activated, with decreasing efficiency by fructose 2-phosphorothioate 6-phosphate, fructose 2,6-bisphosphate, fructose 1,6-bisphosphate and glucose 1,6-bisphosphate. They all display hyperbolic kinetics. Glycerate 2,3-bisphosphate, glyceraldehyde 3-phosphate, CoASAc, oxalate, AMP, ADP, and ATP inhibit the enzyme. At substrate saturation PK was activated by Pi up to a concentration of 0.8 mM. At higher Pi concentrations the enzyme is inhibited. The enzyme is unaffected by most amino acids, only phenylalanine stimulates and tyrosine inhibits.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Piruvato Quinasa/fisiología , Trypanosoma brucei brucei/enzimología , Aminoácidos/farmacología , Animales , Aniones/farmacología , Cationes/farmacología , Estabilidad de Enzimas/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Eritrocitos/parasitología , Cinética , Fosfatos/farmacología , Piruvato Quinasa/aislamiento & purificación , Piruvato Quinasa/metabolismo , Temperatura , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/crecimiento & desarrollo
15.
Mol Biochem Parasitol ; 59(2): 201-10, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8341319

RESUMEN

Most glycosomal enzymes of Trypanosoma brucei carry a relatively high number of positive charges. In at least 3 of the enzymes some of the charges unique to these enzymes are concentrated in 2 distinct areas on the enzymes' surface, about 4 nm apart [4] and these positively charged structural elements have been suggested to be the site of interaction with the trypanocidal drug Suramin. We have synthesized a series of symmetrical long chain molecules with negative charges or strong dipoles at each end. Several of these compounds inhibited the glycosomal enzymes more strongly than Suramin. They also exhibited a specificity for the trypanosome enzymes, when compared with homologous enzymes from other organisms. By varying the chain length of the active compounds, a 4-nm distance between the molecules' extremes proved optimal for inhibition. Tetra-substituted compounds were better than di-substituted. Modifications introduced at the two ends indicated that a planar orientation, with an amide bond linking a phenyl ring to the chain, is preferred. Inhibition kinetics for some of the enzymes indicated the existence of multi-site interactions with the inhibitors.


Asunto(s)
Benzoatos/farmacología , Ácidos Dicarboxílicos/farmacología , Inhibidores Enzimáticos/farmacología , Glucólisis/efectos de los fármacos , Tripanocidas/farmacología , Trypanosoma brucei brucei/enzimología , Animales , Benzoatos/síntesis química , Ácidos Dicarboxílicos/síntesis química , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Humanos , Cinética , Estructura Molecular , Suramina/farmacología , Tripanocidas/síntesis química , Trypanosoma brucei brucei/efectos de los fármacos
16.
Mol Biochem Parasitol ; 55(1-2): 95-104, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1435879

RESUMEN

Expression of the Trypanosoma brucei ornithine decarboxylase (ODC) gene in Escherichia coli behind the lambda phage PR promoter led to the production of a recombinant enzyme having the same subunit molecular weight as the native enzyme [4]. However, when the same gene is expressed behind the tac promoter or the phoA promoter, the ODCs produced by the transformed E. coli have subunit molecular weights approximately 2 kDa higher than that of the native enzyme. Amino terminal sequencing of the recombinant proteins indicates that the ODC synthesized under control of the lambda PR promoter actually starts at the second methionine (Met23) of the open reading frame, whereas those produced in the latter two cases begin at the first methionine (Met1). Analysis of the 5'-end of T. brucei ODC mRNA supports the conclusion that translation initiates at Met23. We postulate that, for the lambda PR promoter, translation initiates at Met23 instead of Met1 because of the formation of a stable secondary structure in the region of the Met1 and the presence of a good E. coli consensus translation initiation site upstream of Met23. We have constructed a new plasmid using the pho A promoter to express recombinant T. brucei ODC starting at Met23 in large quantities.


Asunto(s)
Regulación de la Expresión Génica , Ornitina Descarboxilasa/genética , Regiones Promotoras Genéticas , Biosíntesis de Proteínas , Trypanosoma brucei brucei/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sondas de ADN , ADN Protozoario/química , Electroforesis en Gel de Poliacrilamida , Datos de Secuencia Molecular , Peso Molecular , Conformación de Ácido Nucleico , Ornitina Descarboxilasa/química , Plásmidos , Reacción en Cadena de la Polimerasa , ARN Mensajero/química , ARN Protozoario/química , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Trypanosoma brucei brucei/enzimología
17.
J Nucl Med ; 20(2): 85-91, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-430200

RESUMEN

Mineral loss from bone can be measured accurately and reproducibly by neutron activation of the hand bones using a 5-min irradiation (10(6) n/cm2-sec) with two 200-microgram sources of Cf-252. The hand dose is 7.5 rad equivalent and the dose to the rest of body is 1.5 mrem. Controls (132) and osteoporotic patients (45) were compared. Between ages 20 and 60 the control group showed a bone calcium concentration of 0.177 +/- 0.025 g/cm3, independent of age. Between 60 and 70 the content remained unchanged in men but declined in women to 0.15 +/- 0.2 g/cm3. In all age groups osteoporotic patients in general showed lower calcium content. Comparison of our findings ("Ca") with estimates of bone mineral content obtained by photon absorptiometry ("BMC") yields 0.07 Ca + 0.262 (r = 0.87). Activation analysis of hand bone appears more precise than BMC for the monitoring of bone-mineral loss in each individual and as a measure of treatment efficacy.


Asunto(s)
Análisis por Activación/métodos , Huesos/metabolismo , Calcio/metabolismo , Análisis de Activación de Neutrones/métodos , Osteoporosis/metabolismo , Adulto , Factores de Edad , Anciano , Femenino , Mano , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales
18.
Hum Immunol ; 44(4): 203-9, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8770633

RESUMEN

Forces influencing the composition of the mature TCR repertoire have been well studied in the mouse. In particular, the contribution of MHC molecules in negative and positive selection events of T lymphocytes has been established. To understand whether the allelic polymorphism of HLA-DRB1 molecules can shape the human TCR repertoire, we compared the usage of TCR V beta segments in two cohorts of unrelated individuals who were selected for the expression of HLA-DRB1 alleles. To investigate the potential role of antigenic experience in shaping the TCR repertoire, we compared the usage of V beta gene elements in CD45RO- CD4+ (naive) T cells versus CD45RO+ CD4+ (memory) T cells. A correlation between V beta gene segment usage and HLA-DRB1 alleles could be demonstrated for the repertoire of the naive CD4+ T cells, suggesting a shaping force of the HLA-DRB1 allele on the peripheral TCR repertoire. While the HLA-DRB1 imposed profile in V beta distribution was maintained in CD45RO+ CD4+ T cells, it was less pronounced, indicating that antigenic experience modulates the functional TCR repertoire.


Asunto(s)
Variación Antigénica , Linfocitos T CD4-Positivos/inmunología , Antígenos HLA-DR/genética , Alelos , Cadenas HLA-DRB1 , Heterocigoto , Humanos , Antígenos Comunes de Leucocito/genética , Polimorfismo Genético , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Subgrupos de Linfocitos T/inmunología
19.
Chest ; 97(2): 495-8, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2298082

RESUMEN

A 79-year-old man was given a cumulative dose of 16.5 g of nilutamide for treatment of prostate cancer. He then presented with a respiratory illness having clinical, radiologic and functional characteristics of interstitial pneumonitis. No other cause of pneumonitis was found. Bronchoalveolar lavage showed a lymphocytic alveolitis with an inverted lymphocyte subset ratio. After an 11-week period of drug withdrawal, clinical, radiologic and functional improvement was observed along with a normal alveolar lymphocytosis. Nilutamide therapy was then resumed for five weeks and induced the recurrence of clinical, functional and alveolar abnormalities. Nilutamide treatment was finally stopped and two months later, clinical and functional abnormalities resolved. This observation seems to exemplify the possible diagnostic value of coupling provocation test with BAL cell data in hypersensitivity pneumonitis induced by drugs. In addition, these data support the role of a cell-mediated immunologic mechanism in the pathogenesis of nilutamide-induced pneumonitis.


Asunto(s)
Alveolitis Alérgica Extrínseca/inducido químicamente , Antineoplásicos/efectos adversos , Imidazoles/efectos adversos , Imidazolidinas , Anciano , Alveolitis Alérgica Extrínseca/diagnóstico , Antineoplásicos/uso terapéutico , Líquido del Lavado Bronquioalveolar/citología , Humanos , Imidazoles/uso terapéutico , Masculino , Neoplasias de la Próstata/tratamiento farmacológico
20.
Clin Exp Rheumatol ; 5(4): 379-86, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3326692

RESUMEN

The occurrence of rheumatic disorders in patients treated by long-term haemodialysis (HD) has been emphasized for several years. Complications include carpal tunnel syndrome and various arthropathies. Together with renal osteodystrophy, they are the main limiting factors for the quality of long-term survivals. The pathophysiology is still poorly understood but apatite crystal deposition, aluminum or iron overload and the articular deposition of a new type of amyloid may play a part. We will attempt here to review the available data on these rheumatic disorders in dialysis patients.


Asunto(s)
Artropatías/etiología , Diálisis Renal/efectos adversos , Amiloidosis/etiología , Artritis/etiología , Síndrome del Túnel Carpiano/etiología , Humanos , Artropatías/diagnóstico por imagen , Diálisis Peritoneal/efectos adversos , Radiografía
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