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1.
Leuk Res ; 130: 107308, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37230027

RESUMO

Accelerated phase (AP) CML at onset and have poorer prognosis than CP-CML. We hypothesize that off-license use of second generation TKI (TKI2) as front-line therapy might counterbalance this poor prognosis, with limited toxicity. In "real-life" conditions, newly diagnosed patients meeting the ELN cytological criteria for AP-CML or harboring ACA and treated with first-line TKI2 were included in this retrospective multicenter observational study. We enrolled 69 patients [69.5 % male, median age 49.5 years, median follow-up 43.5 months], segregated into hematologic AP [HEM-AP (n = 32)] and cytogenetically defined AP [ACA-AP (n = 37)]. Hematologic parameters were worse in HEM-AP [spleen size (p = 0.014), PB basophils (p < .001), PB blasts (p < .001), PB blasts+promyelocytes (p < .001), low hemoglobin levels (p < .001)]. Dasatinib was initiated in 56 % patients in HEM-AP and in 27 % in ACA-AP, nilotinib in 44 % and 73 % respectively. Response and survival do not differ, regardless of the TKI2: 81 % vs 84.3 % patients achieved CHR, 88 % vs 84 % CCyR, 73 % vs 75 % MMR respectively. The estimated 5-year PFS 91.5 % (95%CI: 84.51-99.06 %) and 5-year OS 96.84 % (95%CI: 92.61-100 %). Only BM blasts (p < 0.001) and BM blasts+promyelocytes (p < 0.001) at diagnosis negatively influenced OS. TKI2 as front-line therapy in newly diagnosed AP-CML induce excellent responses and survival, and counterbalance the negative impact of advanced disease phase.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Dasatinibe/uso terapêutico , Pirimidinas , Resultado do Tratamento , Inibidores de Proteínas Quinases/uso terapêutico
2.
J Adolesc Young Adult Oncol ; 11(4): 389-393, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34756112

RESUMO

Purpose: Infertility in adolescents and young adult (AYA) survivors of malignant disease remains a major long-term adverse effect, but semen collection for fertility preservation in fertility centers is not always feasible and makes AYAs uncomfortable. We evaluated the feasibility of collecting sperm samples on the ward versus in fertility centers. Methods: Consecutive hospitalized AYA-aged male patients in the Hematology AYA unit (Saint-Louis Hospital, France) between August 2010 and June 2016 with hematological disease and indication of semen collection (n = 95) were included in this retrospective study. Semen quality was analyzed according to World Health Organization guidelines and was compared according to semen collection place: on the ward (n = 46) or in fertility center (n = 49). Results: The median age was median age 19.1 years (range: 13.7-33.3; interquartile range: 17.1-22.8) and 85 patients successfully collected semen. Sperm collection failure was ∼11% and was comparable between the two modalities as were main sperm quality characteristics (semen volume, sperm concentration, total sperm count, progressive motility and vitality, sperm morphology, and multiple anomalies index). Oligospermia was significantly higher in the samples obtained in fertility center (47.7%) than on the ward (26.8%), p = 0.047. Average frozen straws were comparable, 12.2 ± 6.4 on the ward versus 11.9 ± 6.3 in fertility center. Conclusion: Semen collection on the ward is feasible and would be particularly interesting for AYA male patients without altering semen quality characteristics.


Assuntos
Doenças Hematológicas , Preservação do Sêmen , Adolescente , Adulto , Idoso , Criopreservação , Humanos , Masculino , Estudos Retrospectivos , Sêmen , Análise do Sêmen , Motilidade dos Espermatozoides , Adulto Jovem
4.
J Hepatol ; 67(3): 501-507, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28483676

RESUMO

BACKGROUND AND AIMS: Myeloproliferative neoplasms (MPN) are the leading cause of splanchnic vein thrombosis (SVT). Janus kinase 2 gene (JAK2)V617F mutations are found in 80 to 90% of patients with SVT and MPN. Mutations of the calreticulin (CALR) gene have also been reported. However, as their prevalence ranges from 0 to 2%, the utility of routine testing is questionable. This study aimed to identify a group of patients with SVT at high risk of harboring CALR mutations and thus requiring this genetic testing. METHODS: CALR, JAK2V617F and thrombopoietin receptor gene (MPL) mutations were analysed in a test cohort that included 312 patients with SVT. Criteria to identify patients at high risk of CALR mutations in this test cohort was used and evaluated in a validation cohort that included 209 patients with SVT. RESULTS: In the test cohort, 59 patients had JAK2V617F, five had CALR and none had MPL mutations. Patients with CALR mutations had higher spleen height and platelet count than patients without these mutations. All patients with CALR mutations had a spleen height ⩾16cm and platelet count >200×109/L. These criteria had a positive predictive value of 56% (5/9) and a negative predictive value of 100% (0/233) for the identification of CALR mutations. In the validation cohort, these criteria had a positive predictive value of 33% (2/6) and a negative predictive value of 99% (1/96). CONCLUSION: CALR mutations should be tested in patients with SVT, a spleen height ⩾16cm, platelet count >200×109/L, and no JAK2V617F. This strategy avoids 96% of unnecessary CALR mutations testing. Lay summary: Mutations of the CALR gene are detected in 0 to 2% of patients with SVT, thus the utility of systematic CALR mutation testing to diagnose MPN is questionable. This study demonstrates that CALR mutations testing can be restricted to patients with SVT, a spleen height ⩾16cm, a platelet count >200×109/L, and no JAK2V617F. This strategy avoids 96% of unnecessary CALR mutations testing.


Assuntos
Calreticulina/genética , Mutação , Trombose Venosa/genética , Adulto , Feminino , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/genética , Estudos Prospectivos
5.
J Adolesc Young Adult Oncol ; 6(2): 299-306, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27983886

RESUMO

PURPOSE: Adolescents and young adults (AYAs) with cancer are a unique group of patients in terms of disease incidence and biology, outcome, and psychosocial needs. This study aims to correlate the risk of graft-versus-host disease (GvHD) and age in a population of children and young adults with acute leukemia undergoing hematopoietic stem cell transplantation (HSCT) in first complete remission (CR). METHODS: We analyzed the outcome of 153 consecutive children (<15 years), AYAs (15-24 years), and adults (25-35 years) with lymphoblastic or myeloid acute leukemia in first CR who underwent HSCT with matched donors after myeloablative conditioning. GvHD prophylaxis was methotrexate and cyclosporine A (CsA) in all patients. RESULTS: The cumulative incidence of grade II-IV acute GvHD (aGvHD) was significantly higher in AYA patients than in children (subdistribution hazard ratio (SHR), 2.04, p = 0.005) or adults (SHR 1.59, p = 0.048). Both gut and skin aGvHD occurred more frequently in AYA patients. Increasing CsA blood levels with age could not fully account for this difference. No difference in terms of grade III-IV aGvHD was observed. Chronic GvHD was more frequent in AYAs (SHR 2.81, p = 0.007) and adults (SHR 2.31, p = 0.033) than in children. No difference in terms of nonrelated mortality and overall survival was observed among the age subgroups. CONCLUSION: Since GvHD occurrence is strongly correlated to quality of life, specific attention should be paid to AYAs undergoing HSCT. Further studies should investigate the reasons for the excess of GvHD observed in this population.


Assuntos
Doença Enxerto-Hospedeiro/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Enteropatias/epidemiologia , Leucemia Mieloide Aguda/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Dermatopatias/epidemiologia , Doença Aguda , Adolescente , Adulto , Criança , Doença Crônica , Ciclosporina/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Incidência , Enteropatias/prevenção & controle , Metotrexato/uso terapêutico , Mortalidade , Modelos de Riscos Proporcionais , Qualidade de Vida , Indução de Remissão , Índice de Gravidade de Doença , Dermatopatias/prevenção & controle , Taxa de Sobrevida , Transplante Homólogo , Adulto Jovem
7.
J Clin Virol ; 58(4): 733-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24183928

RESUMO

We characterised by pyrosequencing, the dynamics of cytomegalovirus populations harbouring mutations A594V in gene UL97 and A834P and Q578H in gene UL54 in a haematopoietic stem cell transplant recipient. Unexpected re-emergence of A594V and decrease of A834P under CMX001 were shown to depend on both the selection pressure exerted by the antiviral treatments and the immune response.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/genética , Transplante de Células-Tronco Hematopoéticas , Mutação , Adulto , Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Farmacorresistência Viral/genética , Feminino , Genes Virais , Humanos , Adulto Jovem
8.
Br J Haematol ; 162(6): 783-91, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23848933

RESUMO

Myeloproliferative neoplasm-related myelofibrosis is associated with cytopenic or proliferative phases, splenomegaly and constitutional symptoms. Few effective treatments are available and small series suggested that interferon could be an option for myelofibrosis therapy. We performed a retrospective study of pegylated-interferon α-2a (Peg-IFNα-2a) therapy in myelofibrosis. Sixty-two patients treated with Peg-IFNα-2a at 17 French and Belgian centres were included. Responses were determined based on the criteria established by the International Working Group for Myelofibrosis Research and Treatment. Mean follow-up was 26 months. Sixteen of 25 anaemic patients (64%) (eight concomitantly receiving recombinant erythropoietin) achieved a complete response and transfusion-independence was obtained in 5/13 patients (38·5%). Constitutional symptoms resolved in 82% of patients. All five leucopenic patients normalized their leucocyte counts, whereas a normal platelet count was obtained in 5/8 thrombocytopenic patients. Splenomegaly was reduced in 46·5% of patients, and complete resolution of thrombocytosis and leucocytosis were observed in 82·8% and 68·8% of patients, respectively. Side effects (mostly haematological) were mainly of grade 1-2. The only factor independently associated with treatment failure was a spleen enlargement of more than 6 cm below the costal margin. In conclusion, Peg-IFNα-2a induced high response rates with acceptable toxicity in a large proportion of patients with primary and secondary myelofibrosis, especially in early phases.


Assuntos
Interferon-alfa/efeitos adversos , Interferon-alfa/uso terapêutico , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/uso terapêutico , Mielofibrose Primária/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Mielofibrose Primária/patologia , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Blood ; 119(24): 5909-17, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22555971

RESUMO

Diagnosis of gastrointestinal GVHD (GI-GVHD) is based on clinical symptoms and histologic findings. No biomarkers predicting responses to treatment are routinely available even though 30% to 50% of patients will not respond to corticosteroids. In this study, we aimed to evaluate fecal calprotectin, α-1-antitrypsin (α(1)-AT), and elastase at the time of first symptoms as diagnostic and prognostic tools for GI-GVHD in 72 consecutive patients, of whom 51 developed GI-GVHD. The prognostic value of markers was evaluated by their association with complete response (CR) and steroid-resistant (SR) GVHD. Calprotectin and α(1)-AT concentrations increased with GI-GVHD initial stages but patients with initial stage 1 GI-GVHD had similar marker levels to patients without GI-GVHD, so sensitivity to diagnose GI-GVHD was weak. In contrast, calprotectin and α(1)-AT were predictors for SR-GVHD and CR. Multiple regression modeling identified calprotectin and α(1)-AT concentration as independently predicting SR-GVHD together with initial stage > 2 GI-GVHD. Our results showed that fecal calprotectin and α(1)-AT levels at the time of diagnosis are predictive for responses to treatment but are not diagnostic markers for initial stage 1 to 3 GI-GVHD.


Assuntos
Corticosteroides/uso terapêutico , Fezes/química , Trato Gastrointestinal/patologia , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/metabolismo , Complexo Antígeno L1 Leucocitário/metabolismo , alfa 1-Antitripsina/metabolismo , Adolescente , Corticosteroides/farmacologia , Adulto , Idoso , Biomarcadores/metabolismo , Criança , Resistência a Medicamentos , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/metabolismo , Análise de Regressão , Sensibilidade e Especificidade , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
10.
Anticancer Drugs ; 23(7): 754-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22421368

RESUMO

Chronic myeloid leukemia is a chronic myeloproliferative disorder of hematopoietic stem cells that occurs in 10% of cases in women of childbearing age. Treatment is mainly based on tyrosine kinase inhibitors such as imatinib, dasatinib, or nilotinib. However, the maternal and embryofetal safety of these drugs in pregnant women is poorly documented. Here, we report the case of a 23-year-old woman diagnosed with a chronic myeloid leukemia. She was treated with dasatinib while she was diagnosed as being pregnant at 7 weeks of gestation. Obstetric monitoring showed fetal hydrops associated with severe fetal bicytopenia, leading to termination of pregnancy at 16 weeks of gestation. Dasatinib concentrations were 4 ng/ml in maternal plasma (usual concentration), 3 ng/ml in fetal plasma, and 2 ng/ml in amniotic fluid. Fetal karyotype was normal. To our knowledge, this is the first report clearly quantifying the amount of transplacental transfer of dasatinib. Moreover, fetal hematological toxicity (leukopenia and thrombocytopenia), edema, ascites, and pleural effusions described in this case report are well-known side effects of dasatinib in adults. Hence, this case highlights the imputability of dasatinib in this adverse outcome, and clearly questions its safety during pregnancy.


Assuntos
Feto/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Troca Materno-Fetal , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Tiazóis/efeitos adversos , Dasatinibe , Feminino , Humanos , Hidropisia Fetal/etiologia , Leucopenia/etiologia , Gravidez , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/farmacocinética , Tiazóis/farmacocinética , Trombocitopenia/etiologia , Resultado do Tratamento , Adulto Jovem
13.
Haematologica ; 91(5): 687-90, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16670073

RESUMO

Immunohistochemically detected over-expression of P53-related protein (P53+++) and absence of P21(waf1) expression (P21-) correspond to loss of function of the P53-gene in diffuse large B-cell lymphoma (DLBCL) patients. Using immunohistochemistry we examined 80 patients with DLBCL and found that 23% had the P53+++/P21- phenotype while 51% had a germinal center (GC) pattern. Both the P53+++/P21- phenotype and the non-GC pattern were associated with inferior outcome. Notably, the prognostic power of the P53+++/P21- phenotype was restricted to patients with a GC pattern, without effect on outcome of patients with a non-GC phenotype. Our results show that immunohistochemistry can parallel gene expression profiling in addressing clinical variability of DLBCL patients.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/deficiência , Linfoma Difuso de Grandes Células B/genética , Proteínas de Neoplasias/análise , Proteína Supressora de Tumor p53/análise , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bleomicina/administração & dosagem , Ciclo Celular/genética , Estudos de Coortes , Inibidor de Quinase Dependente de Ciclina p21/análise , Inibidor de Quinase Dependente de Ciclina p21/genética , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Epirubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Genes p53 , Centro Germinativo/patologia , Humanos , Imuno-Histoquímica , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/radioterapia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Fenótipo , Prednisona/administração & dosagem , Prognóstico , Radioterapia Adjuvante , Reprodutibilidade dos Testes , Rituximab , Análise de Sobrevida , Taxa de Sobrevida , Vincristina/administração & dosagem
15.
Exp Brain Res ; 167(3): 362-9, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16078031

RESUMO

Transcranial magnetic stimulation (TMS) can be used to study sensorimotor integration in humans non-invasively. Motor excitability has been found to be inhibited when afferent stimuli are given to a peripheral nerve and precede TMS at interstimulus intervals (ISIs) of 20-50 ms. This phenomenon has been referred to as short-latency afferent inhibition (SAI). To better understand the functional meaning of these phenomena, we examined the effect of the size of the receptive field on SAI to cutaneous afferents in upper-limb sensorimotor areas in humans. We examined the effect of the stimulation of the isolated right first (D1), second (D2) and third finger (D3), the right second and third finger together (D23) and the right first three fingers together (D123) on the amplitude of motor evoked potentials (MEPs) to TMS in hand and forearm muscles. We examined the right abductor pollicis brevis (APB), first dorsal interosseous (FDI), extensor carpi radialis (ECR) and flexor carpi radialis (FCR) muscles. Digital stimulation preceded TMS at ISIs of 20-50 ms. The effect of D2 stimulation was MEP inhibition (SAI), which was more marked and consistent in APB and FDI muscles than in ECR and FCR muscles. Similarly, D1 and D3 stimulation caused MEP reduction, while no MEP enhancement could be found to single finger stimulation. In contrast, D123 stimulation induced less effective SAI in upper-limb muscles. MEP potentiation was recorded in some muscles to D123 stimulation. A significant difference between D2 and D123 stimulation was found in APB (ISIs = 30-50 ms) and FDI (ISIs = 40-50 ms) muscles, but not in forearm muscles. The effect to D23stimulation on MEP amplitude was intermediate between those to D2 and D123 stimulation. Our data suggest that motor excitability to cutaneous afferents may be influenced by the size of the receptive fields, this effect being the result of increasing convergence between hand afferents in the somatosensory system. These phenomena appear to be topographically arranged across the representation of upper-limb muscles. These findings may help to understand the functional significance of SAI in normal physiology and pathophysiology.


Assuntos
Neurônios Aferentes/fisiologia , Desempenho Psicomotor/fisiologia , Pele/inervação , Tato/fisiologia , Adulto , Estimulação Elétrica , Potencial Evocado Motor/fisiologia , Feminino , Dedos/fisiologia , Antebraço/inervação , Antebraço/fisiologia , Mãos/inervação , Mãos/fisiologia , Humanos , Masculino , Nervo Mediano/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Limiar Sensorial/fisiologia , Estimulação Magnética Transcraniana
16.
J Neurol Sci ; 217(2): 205-10, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14706225

RESUMO

OBJECTIVE: The aim of the study was to examine intracortical excitability in cerebellar patients. METHODS: Short-latency intracortical inhibition (SICI), long-latency intracortical inhibition (LICI) and intracortical facilitation (ICF) to paired transcranial magnetic stimulation (TMS) were investigated in 8 patients with 'pure' cerebellar syndromes and in 14 age-matched normal controls. The conditioning stimulus for short-latency intracortical inhibition and intracortical facilitation was set at 70% of the resting motor threshold (RMT) and preceded the test stimulus (110-120% of the resting motor threshold) by interstimulus intervals (ISIs) of 1-30 ms. For the long-latency intracortical inhibition determinations, the conditioning stimulus was set at 120% of the resting motor threshold and preceded the test stimulus (also 120% of the resting motor threshold) by interstimulus intervals of 30-500 ms. RESULTS: No statistically significant differences were found between patients and controls as regards either short-latency intracortical inhibition or intracortical facilitation. A significant prevalence of long-latency intracortical inhibition was present in cerebellar patients at interstimulus intervals of 200-500 ms (conditioned MEP amplitude=29-41% of test MEP) as compared to controls (71-96% of test MEP). The amplitude of conditioned MEPs was persistently less than 45% of the test MEP in six patients, who were studied at interstimulus intervals up to 1000 ms. CONCLUSIONS: Long-latency intracortical inhibition was prevalent and abnormally longer-lasting in patients. Tonic hyperactivation of a subpopulation of GABAergic interneurons in the motor cortex of patients may be the mechanism responsible for this abnormality. Our findings seem to be specific to cerebellar diseases and are the opposite of those found in movement disorders such as dystonia and Parkinson's disease. These data suggest that the cerebellum and the basal ganglia may have opposite influences in tuning the excitability of the motor cortex.


Assuntos
Doenças Cerebelares/fisiopatologia , Córtex Motor/fisiopatologia , Inibição Neural/fisiologia , Vias Neurais/fisiopatologia , Adulto , Idoso , Cerebelo/fisiopatologia , Estimulação Elétrica , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Interneurônios/fisiologia , Magnetismo , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Ácido gama-Aminobutírico/metabolismo
17.
Clin Neurophysiol ; 115(2): 348-55, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14744576

RESUMO

OBJECTIVE: The aim of the study was to examine the stimulus-response properties of the excitatory and inhibitory components of corticospinal projections at rest and during voluntary contraction in cerebellar patients. METHODS: We investigated motor evoked potential (MEP) and cortical silent period recruitment curves in response to increasing intensities of transcranial magnetic stimulation in 8 patients with 'pure' cerebellar syndromes and in 14 age-matched controls. The transcranial magnetic stimulation intensity was increased from 90 to 180% of the resting motor threshold. MEP recruitment curves were recorded at rest and during voluntary contraction in the right abductor pollicis brevis muscle. RESULTS: No statistical differences were found between patients and controls in MEP recruitment curves in either the resting or active condition. A significant difference was found between patients and controls in the cortical silent period threshold (patients: 33.2+/-3.4% of maximal stimulator output; controls 39.4+/-3.2%; P=0.01) and recruitment curve, the duration of the cortical silent period being longer in patients at transcranial magnetic stimulation intensities ranging from 90 to 130% of the resting motor threshold (patients: 135-191 ms; controls: 53-158 ms). No changes were found in the silent period evoked by peripheral nerve stimulation. CONCLUSIONS: Inhibitory components of corticospinal projections were recruited with a lower threshold in patients. No abnormalities were found in the recruitment of the excitatory networks. Our data show a prevalence of inhibitory phenomena in the motor cortex of cerebellar patients. These findings would appear to be specific to cerebellar diseases and are the opposite of those previously documented in movement disorders such as dystonia and Parkinson's disease. Our results suggest that the cerebellum and the basal ganglia may counteract each other in modulating the level of motor system excitability.


Assuntos
Ataxia Cerebelar/fisiopatologia , Estimulação Elétrica , Magnetismo , Córtex Motor/efeitos da radiação , Tratos Piramidais/patologia , Adulto , Idoso , Estudos de Casos e Controles , Limiar Diferencial/fisiologia , Relação Dose-Resposta à Radiação , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Inibição Neural/fisiologia
18.
Clin Neurophysiol ; 114(4): 643-51, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12686273

RESUMO

OBJECTIVE: To examine the sensorimotor interactions in cerebellar patients. METHODS: We investigated the effects of electrical stimulation of the second (D2) and fifth (D5) fingers on the amplitude of motor evoked potentials (MEPs) in response to transcranial magnetic stimulation and transcranial electrical stimulation (TES) in the relaxed right abductor digiti minimi muscles of 7 patients with cerebellar syndromes and of 14 age-matched controls. The digital stimulation was set at 3 times the sensory threshold and preceded brain stimulation at interstimulus intervals (ISIs) ranging from 10 to 100 ms. RESULTS: D5 stimulation produced significant MEP inhibition in normal subjects at ISIs of 20-50 ms, while D2 stimulation resulted in a non-significant inhibitory trend with the same intervals. In contrast, digital stimulation had no effect on MEP amplitude in cerebellar patients. A significant difference was found between patients and controls at ISIs of 20-50 ms with D5 stimulation. The difference in amplitude of MEPs conditioned by D5 and D2 stimulation was statistically significant between patients and controls at ISIs of 30 and 50 ms. TES conditioning induced MEP inhibition only at ISIs <40 ms. CONCLUSIONS: Digital stimulation would appear to modulate motor system excitability less effectively in cerebellar patients. MEP inhibition by cutaneous afferences is reduced in response to stimulation of contiguous, as well as non-contiguous fingers. The difference between the conditioning effects of the two fingers is also decreased, and therefore the somatotopic distribution of cutaneomotor inhibition is absent in patients. These abnormalities may contribute to the genesis of cerebellar motor symptoms and their time course suggests involvement of subcortical and cortical sites.


Assuntos
Ataxia Cerebelar/fisiopatologia , Potencial Evocado Motor/fisiologia , Estimulação Magnética Transcraniana , Adulto , Estimulação Elétrica , Feminino , Dedos/inervação , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/fisiologia , Músculo Esquelético/inervação , Inibição Neural/fisiologia , Neurônios Aferentes/fisiologia , Pele/inervação
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