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1.
Encephale ; 45(3): 245-255, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30885442

RESUMEN

The clinical efficacy of neurofeedback is still a matter of debate. This paper analyzes the factors that should be taken into account in a transdisciplinary approach to evaluate the use of EEG NFB as a therapeutic tool in psychiatry. Neurofeedback is a neurocognitive therapy based on human-computer interaction that enables subjects to train voluntarily and modify functional biomarkers that are related to a defined mental disorder. We investigate three kinds of factors related to this definition of neurofeedback. We focus this article on EEG NFB. The first part of the paper investigates neurophysiological factors underlying the brain mechanisms driving NFB training and learning to modify a functional biomarker voluntarily. Two kinds of neuroplasticity involved in neurofeedback are analyzed: Hebbian neuroplasticity, i.e. long-term modification of neural membrane excitability and/or synaptic potentiation, and homeostatic neuroplasticity, i.e. homeostasis attempts to stabilize network activity. The second part investigates psychophysiological factors related to the targeted biomarker. It is demonstrated that neurofeedback involves clearly defining which kind of relationship between EEG biomarkers and clinical dimensions (symptoms or cognitive processes) is to be targeted. A nomenclature of accurate EEG biomarkers is proposed in the form of a short EEG encyclopedia (EEGcopia). The third part investigates human-computer interaction factors for optimizing NFB training and learning during the closed loop interaction. A model is proposed to summarize the different features that should be controlled to optimize learning. The need for accurate and reliable metrics of training and learning in line with human-computer interaction is also emphasized, including targeted biomarkers and neuroplasticity. All these factors related to neurofeedback show that it can be considered as a fertile ground for innovative research in psychiatry.


Asunto(s)
Electroencefalografía , Neurorretroalimentación/métodos , Psiquiatría/métodos , Terapia Cognitivo-Conductual/métodos , Humanos , Trastornos Mentales/terapia
2.
Balkan J Med Genet ; 17(2): 25-35, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25937795

RESUMEN

Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy during childhood. Mutations in dystrophin (DMD) gene are also recognized as a cause of cognitive impairment. We aimed to determine the association between intelligence level and mutation location in DMD genes in Serbian patients with DMD. Forty-one male patients with DMD, aged 3 to 16 years, were recruited at the Clinic for Neurology and Psychiatry for Children and Youth in Belgrade, Serbia. All patients had defined DMD gene deletions or duplications [multiplex ligation-dependent probe amplification (MLPA), polymerase chain reaction (PCR)] and cognitive status assessment (Wechsler Intelligence Scale for Children, Brunet-Lezine scale, Vineland-Doll scale). In 37 patients with an estimated full scale intelligence quotient (FSIQ), six (16.22%) had borderline intelligence (70

3.
Neuroepidemiology ; 36(3): 177-82, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21546779

RESUMEN

BACKGROUND: The aim of this study was to determine prevalence and 15-year survival in Charcot-Marie-Tooth disease (CMT). METHODS: The study covers the period from 1 January 1988 to 31 December 2007 in the territory of Belgrade. Data on a number of CMT-affected persons and their basic demographic characteristics as well as data on the disease were collected from medical records. Data on the course and outcome of the disease were obtained through direct contact with patients, their families and their physicians. RESULTS: We registered 161 patients with CMT in the population of Belgrade. The most frequent type was CMT1. The crude prevalence of CMT disease in the Belgrade population on 31 December 2007 was 9.7/100,000 for all subtypes, 7.1/100,000 for CMT1, and 2.3/100,000 for CMT2. Gender-specific prevalence was 11.2/100,000 for males and 8.3/100,000 for females. The highest age-specific prevalence was registered in the oldest age group (75+ years; 19.1/100,000), and the lowest one in patients aged 5-14 years (5.0/100,000). The cumulative probability of 15-year survival for CMT patients in Belgrade was 85.6 ± 7.8% (44.9 ± 31.8% for males and 98.2 ± 1.8% for females). CONCLUSIONS: The prevalence of CMT found in Belgrade is similar to the prevalence registered in Southern European countries.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/diagnóstico , Enfermedad de Charcot-Marie-Tooth/epidemiología , Vigilancia de la Población/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Sistema de Registros , Serbia/epidemiología , Adulto Joven
4.
J Clin Invest ; 81(6): 1661-5, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3384943

RESUMEN

Anemia has been associated with aluminum intoxication in patients on chronic dialysis and in animals. In studies presented here, in vitro human erythroid culture was used to delineate the effects of aluminum on normal hematopoiesis. Aluminum by itself in routine culture, even at very high levels (1,035 ng/ml), did not significantly affect erythroid colony growth. The addition of human transferrin to the culture, however, resulted in a marked dose-dependent inhibition of erythroid, but not myeloid colony growth. At all doses, CFU-E progenitors showed greater inhibition than burst-forming units (BFU-E). Aluminum inhibition was not overcome by increasing the dose of erythropoietin or adding additional burst-promoting activity to the culture. Inhibition by aluminum was directly related to the number of binding sites on transferrin in the culture, and was not observed in the presence of fully iron-saturated transferrin.


Asunto(s)
Aluminio/farmacología , Células de la Médula Ósea , Eritropoyesis/efectos de los fármacos , Aluminio/metabolismo , Médula Ósea/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Hematopoyesis/efectos de los fármacos , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Transferrina/metabolismo , Transferrina/farmacología
5.
J Clin Invest ; 74(2): 434-41, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6746902

RESUMEN

The hypoproliferative anemia in chronic renal failure has been assumed to be the result of decreased erythropoietin (Ep) production by the damaged kidney and of the shortening of erythrocyte survival. However, many in vitro studies suggest that erythropoietic inhibitors in uremic plasma may contribute to the anemia. To determine the in vivo relevance of uremic inhibitors, increasing amounts of Ep as Ep-rich plasma were infused into six uremic sheep, and their erythropoietic responses were compared with those of nine normal sheep receiving similar amounts of Ep-rich plasma. Three sheep were studied in both normal and uremic states. Ep-rich plasma was obtained from phenylhydrazine- and phlebotomy-induced anemic sheep. Stable uremia was created by subtotal nephrectomy. Erythropoiesis was quantitated by reticulocyte response, ferrokinetics (plasma iron turnover and marrow transit time), and by hemoglobin C synthesis. Ep-rich plasma stimulated erythropoiesis similarly in uremic and normal sheep, regardless of the degree of uremia. Nondialyzed uremic sheep responded as well as dialyzed animals. The anemia was corrected in the uremic dialyzed animals. The anemia was corrected in the uremic sheep after 15-40 daily infusions of Ep-rich plasma, the total dosage depending on the severity of the anemia. Polycythemia was induced when the infusions were continued. Reticulocytes, plasma iron turnover, and erythrocyte mass changes increased as the amount of Ep-rich plasma was increased. These dose-response effects, coupled with the identical erythropoietic response in normal and uremic sheep given the same amount of Ep-rich plasma, imply that there are no physiologically significant erythropoietic inhibitors in uremia.


Asunto(s)
Anemia/fisiopatología , Eritropoyetina/farmacología , Fallo Renal Crónico/complicaciones , Anemia/etiología , Animales , Modelos Animales de Enfermedad , Femenino , Hierro/sangre , Fallo Renal Crónico/fisiopatología , Diálisis Renal , Reticulocitos/fisiología , Ovinos
6.
J BUON ; 12(2): 215-20, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17600875

RESUMEN

PURPOSE: To evaluate the correlation of postmastectomy radiotherapy (PMRT) with local relapse rate, disease-free survival (DFS) and overall survival (OS) in a group of breast cancer (BC) patients at intermediate risk for locoregional relapse (stage I-II with either 1-3 positive axillary nodes, or node-negative grade III BC) treated with radical mastectomy. PATIENTS AND METHODS: We evaluated 482 stage I-II BC patients, with either node-negative grade 3 tumors or with 1-3 positive nodes irrespective of tumor grade, treated with radical mastectomy at our Institute from 1986 to 1994. After mastectomy they received either adjuvant CMF (cyclophosphamide, methotrexate, 5-fluorouracil) chemotherapy (N=172), or adjuvant endocrine therapy (N=310). Postoperative radiotherapy (RT group) to the regional lymph nodes with tumor dose (TD) 48 Gy in 22 fractions was delivered to 199 patients. RESULTS: After a median follow-up of 79.5 months, no difference in relapse rate between the two groups was seen (30.6% in the RT group vs. 36.7% in the no RT group; x(2), p=0.1). Local recurrence rate occurring alone or with distant metastases was 4.52% in the RT group vs. 7.77% in the no RT group (x(2), p=0.1). However, local recurrence rate alone was significantly higher in the RT group compared to the no RT group (2.01 vs. 6.01%, x(2), p=0.041). In premenopausal patients local relapses occurred in 3.2% of patients with postoperative RT and in 8.2% in patients without RT (Fisher's exact test, p=0.48). Non significant difference was registered in postmenopausal patients with (4.76%) or without RT (6.58%). Ten-year DFS and OS were 53.5% and 68.7% in the RT group vs. 52.9% and 75.2% in the no RT group (non significant difference). CONCLUSION: Our results did not show that PMRT significantly influences the incidence of disease relapse, DFS and OS in stage I-II BC patients with intermediate risk for disease relapse. However, it seems that PMRT might influence the occurrence of locoregional recurrence in these patients.


Asunto(s)
Neoplasias de la Mama/radioterapia , Carcinoma Ductal/radioterapia , Carcinoma Lobular/radioterapia , Mastectomía , Recurrencia Local de Neoplasia , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma Ductal/secundario , Carcinoma Ductal/cirugía , Carcinoma Lobular/secundario , Carcinoma Lobular/cirugía , Supervivencia sin Enfermedad , Femenino , Humanos , Metástasis Linfática , Estadificación de Neoplasias , Dosificación Radioterapéutica , Radioterapia Adyuvante , Tasa de Supervivencia
7.
Am J Med ; 110(2): 88-90, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11165548

RESUMEN

PURPOSE: Folate levels are routinely ordered in the evaluation of macrocytosis with or without frank anemia, yet the value of these tests is questionable. We evaluated the clinical utility of folate testing in routine clinical practice. SUBJECTS AND METHODS: We conducted a retrospective review of all serum and erythrocyte folate assays performed over a one-year period at three hospitals. We determined the frequency of low values, then reviewed the medical records of all patients with low values to determine whether low folate levels changed clinician behavior. We also performed a cost analysis to determine the cost of testing per case in which behavior changed. RESULTS: Only 2.3% of the 2,998 folate levels obtained during the study period were low. The low levels were noted in the record in 53% of cases, and folic acid was prescribed or continued at discharge in only 24%. The cost analysis showed that nearly $10,000 was spent in folate testing per patient in which behavior changed. CONCLUSIONS: Folate values were rarely low in the population tested, and low values infrequently led to a change in clinician behavior. Given the limited clinical value of folate tests, we propose that, in cases of macrocytosis with or without anemia, to minimize cost and prevent missed cases of true folate deficiency, empirical supplementation with folic acid should be used in place of testing for deficiency.


Asunto(s)
Anemia Macrocítica/sangre , Anemia Macrocítica/economía , Anemia/sangre , Anemia/economía , Eritrocitos/metabolismo , Ácido Fólico/sangre , Costos de Hospital/estadística & datos numéricos , Análisis Costo-Beneficio , Hospitales de Condado/economía , Hospitales Privados/economía , Hospitales de Veteranos/economía , Humanos , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Estados Unidos
8.
AIDS Res Hum Retroviruses ; 12(16): 1551-8, 1996 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8911581

RESUMEN

HIV-1-infected individuals at various stages of disease harbor virus in their lymphoid organs, which serve as reservoirs of viral replication throughout the course of infection. Hematologic abnormalities are extremely common in HIV-1-infected individuals and occur at all stages of disease. To determine if the bone marrow is a reservoir of HIV-1 in vivo and if active HIV-1 RNA expression in that site is related to hematologic disease in infected individuals, we examined HIV-1 RNA expression in bone marrow biopsies from 37 patients with a broad spectrum of hematologic and HIV-1-related disease. To detect HIV-1 RNA expression, we performed in situ hybridization. Double-label in situ hybridization-immunohistochemistry was used for precise identification of the type of cell expressing viral RNA. Six of 37 (16%) patients demonstrated HIV-1 RNA expression in the bone marrow. Double-label analysis performed on two marrows localized HIV-1 RNA to cells of the macrophage lineage. Active HIV-1 expression correlated with advanced HIV-1-related disease and CD4 cell depletion rather than a specific hematologic or clinical diagnosis. These data suggest that although the bone marrow does not serve as a reservoir of viral expression throughout the course of infection as do the lymphoid organs, HIV-1-expressing cells are present in the bone marrow during late stages of disease. These data also suggest that hematologic abnormalities in the majority of infected individuals may result from indirect effects of HIV-1 such as cytokine dysregulation rather than HIV-1 expression in the bone marrow itself.


Asunto(s)
Médula Ósea/química , VIH-1/genética , ARN Viral/metabolismo , Adulto , Biopsia , Médula Ósea/patología , Femenino , Enfermedades Hematológicas/complicaciones , Humanos , Inmunohistoquímica , Hibridación in Situ , Macrófagos/química , Macrófagos/patología , Masculino , Persona de Mediana Edad
9.
Am J Clin Pathol ; 85(6): 688-93, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3085474

RESUMEN

This study evaluated the utility of the immunoperoxidase method as applied to bone marrow sections in the diagnosis of patients with monoclonal gammopathies. Intracellular immunoglobulin light chains were identified in fixed, decalcified bone marrow biopsy sections from 66 patients with monoclonal proteins, using an avidin-biotin-peroxidase complex immunoperoxidase method. In all cases the predominant light chain identified in the bone marrow biopsy correlated with the monoclonal light chain identified in the serum. In addition, a light chain ratio was defined that correlated with the clinical diagnoses. The light chain ratios were highest in patients with multiple myeloma and were significantly different from those with monoclonal gammopathy of undetermined significance. There was no correlation between level of serum monoclonal protein and light chain ratios. The ratios were also high in patients with macroglobulinemia, primary amyloidosis, and renal disease secondary to monoclonal proteins but without overt myeloma. Determination of light chain ratios differentiated patients with multiple myeloma from those with monoclonal gammopathy of undetermined significance and helped identify patients with end organ damage secondary to monoclonal proteins but without overt myeloma.


Asunto(s)
Biopsia/métodos , Médula Ósea/patología , Hipergammaglobulinemia/clasificación , Técnicas para Inmunoenzimas , Gammopatía Monoclonal de Relevancia Indeterminada/clasificación , Humanos , Cadenas Ligeras de Inmunoglobulina/análisis , Cadenas kappa de Inmunoglobulina/análisis , Cadenas lambda de Inmunoglobulina/análisis , Gammopatía Monoclonal de Relevancia Indeterminada/patología , Mieloma Múltiple/inmunología , Macroglobulinemia de Waldenström/inmunología
10.
Psychiatr Genet ; 11(4): 201-5, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11807410

RESUMEN

A number of human hereditary neuromuscular and neurodegenerative disorders are caused by the expansion of trinucleotide repeats within certain genes. The molecular mechanisms that underlie these expansions are not yet known. We have analyzed six trinucleotide repeat-containing loci [spinocerebellar ataxias (SCA1, SCA3, SCA8), dentatorubral-pallidoluysian atrophy (DRPLA), Huntington chorea (HD) and fragile X syndrome (FRAXA)] in myotonic dystrophy type 1 (DM1) patients (n = 52). As controls, we analyzed two groups of subjects: healthy control subjects (n =133), and a group of patients with non-triplet neuromuscular diseases (n = 68) caused by point mutations, deletions or duplications (spinal muscular atrophy, Charcot-Marie-Tooth disease, type 1A, hereditary neuropathy with liability to pressure palsies, and Duchenne and Becker muscular dystrophy). Allele frequency distributions for all tested loci were similar in these three groups with the exception of the SCA1 locus. In DM1 patients, the SCA1 allele with 31 CAG repeats account for 40.4% of all chromosomes tested, which is significantly higher than in two other groups (11.3% in healthy controls and 6.6% in the group of non-triplet diseased patients; P < 0.001, Fisher's exact test). This is consistent with our previous findings in HD patients. The absence of this association in non-triplet diseases as well as in healthy controls could indicate a possible role of this SCA1 allele with 31 repeats in triplet diseases. Here we discuss a possible role of the SCA1 region in pathological trinucleotide repeat expansions.


Asunto(s)
Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Ataxias Espinocerebelosas/genética , Repeticiones de Trinucleótidos , Alelos , Ataxina-1 , Ataxinas , Secuencia de Bases , ADN/sangre , ADN/genética , Cartilla de ADN , Femenino , Frecuencia de los Genes , Humanos , Masculino , Valores de Referencia
11.
Acad Med ; 65(9): 604-8, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2400481

RESUMEN

The authors examined how satisfied patients and residents were before and after the restructuring of the general medicine clinic at a large urban teaching hospital in 1985; the change to a longitudinal care clinic was made to provide greater continuity of care, more consistent access of residents to attending physicians, and a more structured educational curriculum. Questionnaires to assess satisfaction were administered three weeks before and ten months after the change to all 80 of the second- and third-year residents. A convenience sample of 310 patients seen during a two-week period before the change and another such sample of 267 patients seen during a two-week period ten months after the change comprised the patients who completed a patients' satisfaction questionnaire. The residents were significantly more satisfied with the quality of care, functioning, and educational value of the new longitudinal care clinic. Their average overall rating of satisfaction (on a scale where 1 = completely dissatisfied and 5 = completely satisfied) increased from 2.3 to 3.7 (p less than .001). Unexpectedly, the patients were "very satisfied" with both clinic models and their overall ratings changed little (4.5 before, 4.4 after). In addition, the patients' and residents' before-and-after perceptions of the quality of care delivered in the clinic differed substantially. These findings show that the longitudinal care clinic significantly enhanced the satisfaction of the residents but not of the patients. Furthermore, the data suggest that results from standardized patients' satisfaction surveys may not accurately assess the quality of care being delivered.


Asunto(s)
Comportamiento del Consumidor , Medicina Interna/organización & administración , Internado y Residencia , Servicio Ambulatorio en Hospital/organización & administración , Satisfacción Personal , Continuidad de la Atención al Paciente , Humanos , Minnesota , Innovación Organizacional , Calidad de la Atención de Salud
15.
Eur J Neurol ; 13(5): 451-4, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16722967

RESUMEN

The purpose of this investigation was to determine survival and mortality in patients with myotonic dystrophy type 1 (DM1) in the Belgrade population within the period from 1983 to 2002. Data of a number of diagnosed DM1 patients with their demographic, clinical and genetic characteristics were gathered from hospital records in all neurologic institutions in Belgrade for the period 1983-2002. Death certificates were reviewed to determine the cause of death. Survival analysis by life table method and Cox proportional hazard model was performed. Within the observed period, in the population of Belgrade, 15 fatal outcomes among 101 patients with DM1 were registered. Average DM1 mortality rate was 0.5/1,000,000 (95% CI 0.3-0.8), and standardized mortality ratio (SMR) was 5.3. A significant inverse correlation was found between age at onset of DM1 and CTG repeats (P=0.023). The cumulative probability of 15-year survival for DM1 patients in Belgrade was 49+/-5% (48+/-2% for males and 50+/-7% for females). Younger age at onset was a significant unfavorable prognostic factor (hazard ratio=4.2; P=0.012).


Asunto(s)
Distrofia Miotónica/terapia , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Distrofia Miotónica/mortalidad , Probabilidad , Estudios Retrospectivos , Análisis de Supervivencia , Factores de Tiempo , Yugoslavia/epidemiología
16.
Acta Neurol Scand ; 111(4): 274-7, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15740580

RESUMEN

OBJECTIVES: Analysis of the CTG-repeat number and three biallelic markers, Alu(+/-), HinfI(+/-), and TaqI(+/-), in the DMPK gene in healthy and myotonic dystrophy type 1 (DM1) Serbian individuals. Also, the consideration of haplotypes in the light of the proposed models of CTG-repeat evolution and origin of the DM1 mutation. MATERIALS AND METHODS: Markers were analyzed by PCR and haplotypes were obtained on 203 unrelated normal chromosomes and 24 unrelated DM1 chromosomes. RESULTS: A strong linkage disequilibrium was detected between the three biallelic markers alone (P <0.0001) and between distinct CTG-repeat size classes and reconstructed haplotypes. Greater than 98% of normal chromosomes contain (+++) and (- - -) haplotypes. The (+++) haplotype is the most common, while the (CTG)(9-17) are the most frequent alleles. We found a complete association of (+++) haplotype with (CTG)(> or =18) and mutated alleles. CONCLUSIONS: (CTG)(9-17)/(+++) haplotype is the ancestral haplotype and DM1 mutation occurred on (CTG)(18-35)/+++ chromosome.


Asunto(s)
Distrofia Miotónica/genética , Proteínas Serina-Treonina Quinasas/genética , Estudios de Casos y Controles , Femenino , Marcadores Genéticos , Haplotipos , Humanos , Masculino , Proteína Quinasa de Distrofia Miotónica , Linaje , Repeticiones de Trinucleótidos , Yugoslavia
17.
Br J Haematol ; 56(2): 323-32, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6691924

RESUMEN

The effect of hormonal interactions on human erythroid colony growth has been studied using the beta adrenergic agonist, isoproterenol. The growth of colonies derived from both erythroid burst-forming cells (BFU-E) and erythroid colony-forming cells (CFU-E) was enhanced in the presence of isoproterenol. While isoproterenol was effective at all concentrations of erythropoietin (Ep) in cultures of marrow cells, an increase in BFU-E-derived colonies in peripheral blood cultures could be detected only at suboptimal levels of Ep concentrations. The isoproterenol effect was blocked by an agent with beta 2 receptor specificity (butoxamine), and L-isomeric configuration (L-propranolol). The stimulatory effect appeared to be mediated by a receptor different from that for Ep or for phytohaemagglutinin-stimulated leucocyte conditioned medium. Circulating BFU-E from eight patients with polycythaemia vera were also studied. Those colonies which grew in the absence of added Ep increased with isoproterenol; in cultures from normal subjects and in patients with secondary erythrocytosis, agonist stimulation was seen only in the presence of Ep. These studies provide evidence that the growth of both normal and neoplastic erythroid progenitors may be modulated by hormonal interactions.


Asunto(s)
Eritropoyesis/efectos de los fármacos , Células Madre Hematopoyéticas/efectos de los fármacos , Isoproterenol/farmacología , Policitemia/sangre , Butoxamina/farmacología , Carbacol/farmacología , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Relación Dosis-Respuesta a Droga , Humanos , Fenilefrina/farmacología , Policitemia Vera/sangre , Practolol/farmacología , Propranolol/farmacología
18.
J Lab Clin Med ; 112(1): 23-7, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3260614

RESUMEN

Elevation of intracellular free calcium (Ca++) is an early activation event that occurs as a result of ligand binding in several human cell systems. In this report, erythropoietin, the major hormone governing erythroid differentiation, was found to elicit an increase in Ca++ in human bone marrow mononuclear cells. Two chelators of intracellular calcium, quin 2 and the more specific and sensitive analogue, fura-2, were used to characterize the response evoked by both recombinant and native hormone. Erythropoietin caused a rapid, dose-dependent rise (within seconds) in Ca++ in bone marrow mononuclear cells, which could be prevented by preincubation of hormone with a rabbit erythropoietin antiserum. The erythropoietin response did not occur in purified populations of T- or B-lymphocytes. These studies suggested that increased Ca++ on erythropoietin binding may be an early transmembrane signal in hormone action.


Asunto(s)
Células de la Médula Ósea , Calcio/metabolismo , Eritropoyetina/farmacología , Aminoquinolinas , Linfocitos B/metabolismo , Benzofuranos , Médula Ósea/metabolismo , Células Cultivadas , Quelantes , Colorantes Fluorescentes , Fura-2 , Humanos , Linfocitos T/metabolismo
19.
Blood ; 80(12): 3079-89, 1992 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-1281689

RESUMEN

The S17 murine stromal cell line was infected with retroviral vectors encoding the v-src and c-src oncogenes and cells expressing high levels of either pp60v-src or pp60c-src were isolated. Long-term bone marrow cultures (LTBMCs) established with these different stromal cell lines showed that progenitor cells proliferated to a greater extent in cultures with stromal cells that over-expressed either c-src or v-src. An increase in the number of granulocytes, monocytes, and colony-forming units granulocyte-macrophage (CFU-GM) in the nonadherent cell population of LTBMCs prepared with S17/v-src or S17/c-src stromal cells was observed. Conditioned media from the S17/v-src and S17/src stromal cell lines stimulated the formation of CFU-GM in the absence of additional hematopoietic cell growth factors. Conditioned media from S17/v-src and S17/c-src stimulated proliferation of the granulocyte-macrophage colony-stimulating factor (GM-CSF)-responsive cell line FDCP-1 and this stimulation was inhibited by neutralizing antisera to murine GM-CSF. An increase in the concentration of GM-CSF was confirmed by enzyme-linked immunosorbent assay. No secretion of interleukin-1 alpha (IL-1 alpha) or tumor necrosis factor-alpha was detected by any of the stromal cell lines. There was no increase in the secretion of either CSF-1 or IL-6 by either S17/v-src or S17/c-src. The addition of 1 micrograms/mL monoclonal anti-GM-CSF antibody to LTBMCs caused a decrease in the number of nonadherent cells in cultures established with each of the different stromal cell lines. Northern blot analysis showed no difference in the level of GM-CSF RNA among the different stromal cell lines. These studies suggest that the increased proliferation of hematopoietic progenitor cells in LTBMCs with S17/v-src or S17/c-src cells may result from a posttranscriptional event that elevates production of GM-CSF by the S17/c-src and S17/v-src stromal cells.


Asunto(s)
Médula Ósea/fisiología , Genes src , Hematopoyesis , Células Madre Hematopoyéticas/fisiología , Células 3T3 , Animales , Secuencia de Bases , Northern Blotting , Línea Celular , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Citocinas/análisis , Citocinas/genética , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Vectores Genéticos , Células Madre Hematopoyéticas/citología , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Reacción en Cadena de la Polimerasa , Proteínas Quinasas/análisis , ARN/genética , ARN/aislamiento & purificación , Retroviridae/genética , Transfección
20.
Blood ; 87(1): 238-44, 1996 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-8547647

RESUMEN

Expression of either the BCR-ABL or the v-abl oncogene in the factor-dependent murine myeloid cell line FDCP-1 results in growth factor independence. Studies with temperature-sensitive mutants of v-abl show that this growth factor independence is oncogene dependent. Likewise, cells expressing a kinase inactive mutant of BCR-ABL did not grow in the absence of interleukin-3 (IL-3). Conditioned media from cells expressing either v-abl or BCR-ABL contained growth factor(s) capable of stimulating the proliferation of uninfected FDCP-1 cells. Based on enzyme-linked immunosorbent assay studies and antibody neutralization studies, the major growth factor present in these conditioned media is IL-3. Because of the importance of SH2 domains in regulating substrate interactions, we examined the ability of SH2 deletion mutants in BCR-ABL to induce growth factor independence. Cells expressing a mutant of BCR-ABL lacking the SH2 domain were growth factor independent; however, they did not secrete growth factors. This finding suggests that while IL-3 produced by cells infected with BCR-ABL may contribute to autocrine or paracrine growth factor independence, expression of an activated tyrosine kinase alone may be able to induce growth factor independence. Furthermore, the secretion of cytokines maybe correlated with a specific region of the BCR-ABL oncogene, suggesting that activation (phosphorylation) of specific substrates may be critical for transcriptional activation of cytokine genes.


Asunto(s)
Proteínas de Fusión bcr-abl/fisiología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Interleucina-3/metabolismo , Proteínas Tirosina Quinasas/fisiología , Dominios Homologos src , Animales , Anticuerpos Monoclonales/farmacología , División Celular/efectos de los fármacos , Línea Celular , Medios de Cultivo Condicionados/farmacología , Proteínas de Fusión bcr-abl/química , Proteínas de Fusión bcr-abl/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Interleucina-3/antagonistas & inhibidores , Interleucina-3/inmunología , Ratones , Mutagénesis Sitio-Dirigida , Proteínas Oncogénicas v-abl/fisiología , Proteínas Tirosina Quinasas/química , Proteínas Tirosina Quinasas/genética , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia , Transfección
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