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1.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469325

RESUMEN

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Resumo Crotalaria (Linnaeus, 1753) (Fabaceae) ocorre abundantemente em regiões tropicais e subtropicais e tem cerca de 600 espécies conhecidas. Estas plantas são amplamente utilizadas na agricultura, principalmente como cobertura e adubos verdes, além da sua utilização no manejo de fitonematoides. Uma característica marcante destas espécies é a produção de alcalóides pirrolizidinicos (APs), aleloquímicos secundários envolvidos na defesa das plantas contra os herbívoros. Nas espécies de Crotalaria, a monocrotalina é a AP predominante, que tem muitas atividades biológicas relatadas, incluindo citotoxicidade, tumorigenicidade, hepatotoxicidade e neurotoxicidade, além de uma vasta gama de interações ecológicas. Assim, estudos têm procurado elucidar os efeitos desse composto para promover um incremento na flora e fauna (principalmente insetos e nematoides) associados aos agroecossistemas, favorecendo o controle biológico natural. Esta revisão compila informações sobre a monocrotalina, mostrando tais efeitos nesses ambientes, tanto acima como abaixo do solo e a sua potencial utilização em programas de manejo de pragas.

2.
Braz. j. biol ; 84: e256916, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355874

RESUMEN

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Resumo Crotalaria (Linnaeus, 1753) (Fabaceae) ocorre abundantemente em regiões tropicais e subtropicais e tem cerca de 600 espécies conhecidas. Estas plantas são amplamente utilizadas na agricultura, principalmente como cobertura e adubos verdes, além da sua utilização no manejo de fitonematoides. Uma característica marcante destas espécies é a produção de alcalóides pirrolizidinicos (APs), aleloquímicos secundários envolvidos na defesa das plantas contra os herbívoros. Nas espécies de Crotalaria, a monocrotalina é a AP predominante, que tem muitas atividades biológicas relatadas, incluindo citotoxicidade, tumorigenicidade, hepatotoxicidade e neurotoxicidade, além de uma vasta gama de interações ecológicas. Assim, estudos têm procurado elucidar os efeitos desse composto para promover um incremento na flora e fauna (principalmente insetos e nematoides) associados aos agroecossistemas, favorecendo o controle biológico natural. Esta revisão compila informações sobre a monocrotalina, mostrando tais efeitos nesses ambientes, tanto acima como abaixo do solo e a sua potencial utilização em programas de manejo de pragas.


Asunto(s)
Animales , Artrópodos , Alcaloides de Pirrolicidina , Crotalaria , Fabaceae , Monocrotalina/toxicidad
3.
Braz J Biol ; 84: e256916, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35043839

RESUMEN

Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Asunto(s)
Artrópodos , Crotalaria , Fabaceae , Alcaloides de Pirrolicidina , Animales , Monocrotalina/toxicidad
4.
Sci Rep ; 11(1): 4728, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33633186

RESUMEN

Pulmonary vein isolation (PVI) using cryoenergy is safe and efficient for treatment of atrial fibrillation (AF). Pre-existing upper gastrointestinal (GI) pathologies have been shown to increase the risk for AF. Therefore, this study aimed at assessing incidental pathologies of the upper GI tract in patients scheduled for PVI and to analyse the impact of patients' characteristics on PVI safety outcome. In 71 AF patients, who participated in the MADE-PVI trial, oesophagogastroduodenoscopy and endosonography were prospectively performed directly before and the day after PVI to assess pre-existing upper GI pathologies and post-interventional occurrence of PVI-associated lesions. Subgroup analysis of the MADE-PVI trial identified clinically relevant incidental findings in 53 patients (74.6%) with age > 50 years being a significant risk factor. Pre-existing reflux oesophagitis increased risk for PVI-associated mediastinal oedema, while patients already treated with proton pump inhibitors (PPI) had significantly fewer mediastinal oedema. Our results suggest that AF patients with pre-existing reflux oesophagitis are at higher risk for PVI-associated mediastinal lesions, which is decreased in patients with constant PPI-treatment prior to PVI. Since PVI-associated mediastinal lesions are regarded as surrogate parameter for an increased risk of the fatal complication of an oesophago-atrial fistula, our findings hint at a beneficial effect of pre-interventional prophylactic PPI-treatment to reduce risk for PVI-associated complications.German Clinical Trials Register (DRKS00016006; date of registration: 17/12/2018).


Asunto(s)
Criocirugía/métodos , Inhibidores de la Bomba de Protones/uso terapéutico , Venas Pulmonares/cirugía , Anciano , Fibrilación Atrial/cirugía , Criocirugía/efectos adversos , Femenino , Reflujo Gastroesofágico/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
6.
Ann Oncol ; 27(12): 2149-2160, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27701070

RESUMEN

The European Society for Medical Oncology (ESMO) consensus conference on mature B-cell lymphomas and chronic lymphocytic leukaemia (CLL) was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (i) the elderly patient, (ii) prognostic factors suitable for clinical use and (iii) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address four clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the four questions assigned to their group. These recommendations were then presented to the entire panel and a consensus was reached. This manuscript presents recommendations dedicated to the second area of interest, i.e. prognostic factors suitable for clinical use. The four topics [i.e. interim positron emission tomography (PET), TP53 mutations, cell of origin (COO) and minimal residual disease (MRD)] were primarily chosen because of the bulk of available data together with the lack of clear guidance regarding their use in clinical practice and within clinical trials. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript. The panel acknowledged that detection of TP53 inactivation by deletion or mutation in CLL should be implemented in clinical practice (level of evidence I, strength of recommendation A). Due to their potentially high prognostic value, at least in some lymphoma entities, implementation of interim PET, COO and MRD was highly recommended in the context of clinical trials. All expert panel members approved this final article.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células B/patología , Linfoma/patología , Oncología Médica , Anciano , Humanos , Leucemia Linfocítica Crónica de Células B/epidemiología , Linfoma/epidemiología , Linfoma de Células B/epidemiología , Pronóstico , Factores de Riesgo , Sociedades Médicas , Suiza
8.
Leukemia ; 29(2): 456-63, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25027518

RESUMEN

Follicular lymphoma (FL) with a t(14;18) is a B-cell neoplasm clinically characterized by multiple recurrencies. In order to investigate the clonal evolution of this lymphoma, we studied paired primary and relapse tumor samples from 33 patients with recurrent non-transformed t(14;18)-positive FL. We reconstructed phylogenetic trees of the evolution by taking advantage of the activation-induced cytidine deaminase (AID)-mediated somatic hypermutation (SHM) active in the germinal center reaction using sequences of the clonal VHDHJH rearrangements of the immunoglobulin heavy chain (IGH) locus. Mutational analysis of the IGH locus showed evidence for ongoing somatic mutation and for counter-selection of mutations affecting the BCR conformation during tumor evolution. We further followed evolutionary divergence by targeted sequencing of gene loci affected by aberrant SHM as well as of known driver genes of lymphomagenesis, and by array-based genome-wide chromosomal imbalance and DNA methylation analysis. We observed a wide spectrum of evolutionary patterns ranging from almost no evolution to divergent evolution within recurrent non-transformed t(14;18) FL. Remarkably, we observed a correlation of the magnitude of evolutionary divergence across all genetic and epigenetic levels suggesting co-evolution. The distribution of coding mutations in driver genes and the correlation with SHM suggest CREBBP and AID to be potential modifiers of genetic and epigenetic co-evolution in FL.


Asunto(s)
Epigénesis Genética , Linfoma Folicular/genética , Linfoma Folicular/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Cromosomas/ultraestructura , Biología Computacional , Citidina Desaminasa/genética , Metilación de ADN , Análisis Mutacional de ADN , Epigenómica , Evolución Molecular , Eliminación de Gen , Genómica , Humanos , Inmunoglobulinas/inmunología , Persona de Mediana Edad , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Filogenia , Polimorfismo de Nucleótido Simple , Receptores de Antígenos de Linfocitos B/genética , Recurrencia , Translocación Genética
9.
Leukemia ; 28(6): 1299-307, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24342950

RESUMEN

In this study, we compared immunoglobulin heavy-chain-gene-based minimal residual disease (MRD) detection by real-time quantitative PCR (RQ-PCR) and next-generation sequencing (NGS) to assess whether NGS could overcome some limitations of RQ-PCR and further increase sensitivity, specificity, accuracy and reproducibility. In total, 378 samples from 55 patients with acute lymphoblastic leukemia (ALL), mantle cell lymphoma (MCL) or multiple myeloma (MM) were investigated for clonotype identification, clonotype identity and comparability of MRD results. Forty-five clonotypes were identified by RQ-PCR and 49 by NGS. Clonotypes identified by both tools were identical or >97% homologous in 96% of cases. Both tools were able to routinely reach a sensitivity level of 1 × E-05. A good correlation of MRD results was observed (R=0.791, P<0.001), with excellent concordance in 79.6% of cases. Few discordant cases were observed across all disease subtypes. NGS showed at least the same level of sensitivity as allele-specific oligonucleotides-PCR, without the need for patient-specific reagents. We conclude that NGS is an effective tool for MRD monitoring in ALL, MCL and MM. Prospective comparative analysis of unselected cases is required to validate the clinical impact of NGS-based MRD assessment.


Asunto(s)
Biomarcadores de Tumor/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Linfoma de Células del Manto/diagnóstico , Mieloma Múltiple/diagnóstico , Neoplasia Residual/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , ADN de Neoplasias/genética , Reordenamiento Génico , Genes de Inmunoglobulinas , Humanos , Linfoma de Células del Manto/genética , Mieloma Múltiple/genética , Neoplasia Residual/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Células Tumorales Cultivadas
10.
Ann Oncol ; 24(6): 1609-15, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23393125

RESUMEN

BACKGROUND: Long-term clinical and molecular remissions in patients with follicular lymphoma (FL) following high-dose therapy (HDT) and autologous stem cell transplantation (ASCT) have been evaluated in only a few studies. Results are especially limited for second-line HDT with BEAM (BCNU, etoposide, cytarabine and melphalan). PATIENTS AND METHODS: Sixty patients with FL received ASCT in our institution (18 first-line with total body irradiation and cyclophosphamide, 34 second-line with BEAM and 8 ≥ third-line with BEAM). In the case of long-term remission (>6 years; N = 17), peripheral blood was tested for minimal residual disease by t(14;18)- and IGH-PCR. RESULTS: Ten-year overall survival, progression-free survival and freedom from progression (FFP) after first-line ASCT were 79%, 57% and 64% after second-line ASCT 41%, 35% and 42%, respectively. Prognostic factors for FFP were treatment line and FLIPI (Follicular Lymphoma International Prognostic Index). Ten-year FFP for second-line ASCT and low-risk FLIPI was 57%, intermediate risk 37% and high risk 33%. No relapses occurred after 6 years following ASCT. Sixteen patients developed sustained long-term clinical and molecular remissions of up to 17.5 years. CONCLUSION: Sustained long-term clinical and molecular remissions can be achieved following ASCT, including HDT with BEAM in second line.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/cirugía , Trasplante de Células Madre/métodos , Adulto , Anciano , Carmustina/administración & dosificación , Estudios de Cohortes , Terapia Combinada/métodos , Terapia Combinada/mortalidad , Citarabina/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Linfoma Folicular/mortalidad , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Podofilotoxina/administración & dosificación , Inducción de Remisión/métodos , Trasplante de Células Madre/mortalidad , Factores de Tiempo , Trasplante Autólogo , Resultado del Tratamiento
11.
Ann Hematol ; 91(11): 1765-72, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22926531

RESUMEN

In most patients, mantle cell lymphoma (MCL) shows an aggressive clinical course with a continuous relapse pattern and a median survival of only 3-5 years. In the current study generation of the European MCL Network, the addition of high-dose Ara-C to R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone)-like regimen followed by myeloablative consolidation achieved a significant improvement of progression-free survival in younger patients. In elderly patients, rituximab maintenance led to a marked prolongation of remission duration. Emerging strategies include mammalian target of rapamycin (mTOR) inhibitors, proteasome inhibitors, immune modulatory drugs, Bruton's tyrosine kinase inhibitors and others, all based on the dysregulated control of cell cycle machinery and impairment of several apoptotic pathways. Combination strategies are currently being investigated in numerous trials, but their introduction into clinical practice and current treatment algorithms remains a challenge. In the current survey, the application of the molecular targeted compounds were collected and evaluated by a representative national network of 14 haematological institutions. Optimised strategies are recommended for clinical routine. Future studies will apply individualised approaches according to the molecular risk profile of the patient.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Medicina Basada en la Evidencia , Linfoma de Células del Manto/tratamiento farmacológico , Adulto , Factores de Edad , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Niño , Conferencias de Consenso como Asunto , Quimioterapia de Consolidación/efectos adversos , Quimioterapia de Consolidación/métodos , Unión Europea , Encuestas de Atención de la Salud , Humanos , Quimioterapia de Inducción/efectos adversos , Quimioterapia de Inducción/métodos , Linfoma de Células del Manto/prevención & control , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/prevención & control , Análisis de Supervivencia
12.
Leukemia ; 23(11): 2007-17, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19641522

RESUMEN

Rituximab-containing regimens are becoming a therapeutic standard in chronic lymphocytic leukemia (CLL), so that a validation of flow cytometric minimal residual disease (MRD) quantification (MRD flow) in the presence of this antibody is necessary. We therefore compared results obtained by real-time quantitative (RQ)-PCR to MRD flow in 530 samples from 69 patients randomized to receive chemotherapy or chemotherapy plus rituximab. Quantitative MRD levels assessed by both techniques were closely correlated irrespective of therapy (r=0.95). The sensitivity and specificity of MRD flow was not influenced by the presence of rituximab. With 58.9% positive and 26.4% negative samples by both techniques, 85.3% of assessments (452/530) were qualitatively concordant between MRD flow and RQ-PCR. Discordant samples were typically negative by MRD flow and simultaneously positive close to the detection limit of the PCR assays, indicating a higher sensitivity of PCR for very low MRD levels. However, 93.8% of all samples were concordantly classified by both methods using a threshold of 10(-4) to determine MRD positivity. MRD flow and PCR are equally effective for MRD quantification in rituximab-treated CLL patients within a sensitivity range of up to 10(-4), whereas PCR is more sensitive for detecting MRD below that level.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Monitoreo de Drogas/normas , Citometría de Flujo/normas , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino , Linfocitos B/citología , Linfocitos B/efectos de los fármacos , Monitoreo de Drogas/métodos , Femenino , Citometría de Flujo/métodos , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Límite de Detección , Masculino , Persona de Mediana Edad , Neoplasia Residual/diagnóstico , Neoplasia Residual/tratamiento farmacológico , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rituximab , Sensibilidad y Especificidad
13.
Ann Oncol ; 20(4): 722-8, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19179546

RESUMEN

BACKGROUND: Pattern and outcome of disease recurrence after autologous stem-cell transplantation (autoSCT) for follicular lymphoma (FL) is not well known. PATIENTS AND METHODS: Relapse cases were identified from 241 consecutive patients autografted for disseminated untransformed FL from 1990 to 2002 in three institutions. Prognostic factors for relapse and outcome after relapse were analyzed by log-rank comparisons and Cox regression analyses. RESULTS: One hundred and three relapses occurred. The 10-year relapse probability was 47%. Median time from autoSCT to relapse was 20 (2-128) months. Only three relapses were observed later than 6 years posttransplant. Median survival after relapse was 8.3 years. Patients with disease recurrence within 1 year from transplant and those who had received autoSCT as second-line treatment had significantly reduced survival by multivariate analysis, whereas Follicular Lymphoma International Prognostic Index score, age, remission status at autoSCT, high-dose regimen, and ex vivo purging had no impact. CONCLUSIONS: FL recurrence after autoSCT follows a biphasic pattern with continuing relapse during the first 6 years and only few events thereafter. The prognosis after relapse is relatively good and appears to be comparable to that of disease recurrence after standard treatment. The situation is less favorable for patients who relapse within the first posttransplant year.


Asunto(s)
Linfoma Folicular/cirugía , Trasplante de Células Madre , Estudios de Seguimiento , Humanos , Linfoma Folicular/patología , Recurrencia , Acondicionamiento Pretrasplante , Trasplante Autólogo
14.
Mol Cell Biochem ; 314(1-2): 133-41, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18473122

RESUMEN

Overexpression of the Galphaq-protein has been shown to result in hypertrophic and dilated cardiomyopathy. This study investigated Ca(2+ )sensitivity of tension and myosin-ATPase activity in skinned fiber preparations of male and female wildtype (WT; n = 12) and transgenic mice with a cardiac specific overexpression of the Galphaq-protein (Galphaq-OE; n = 11). In addition, the phosphorylation status of troponin I was measured. Ca(2+) sensitivity of tension was increased in Galphaq-OE with a significant reduction in the half-maximum Ca(2+) concentration (EC(50)) compared to WT. Similarly, Ca(2+) sensitivity of myosin ATPase activity was increased in Galphaq-OE when comparing Galphaq-OE to WT. Maximum Ca(2+)-dependent tension and ATPase activity were both enhanced in Galphaq-OE compared to WT littermates. Phosphorylation of troponin I was significantly reduced in Galphaq-OE compared to WT. In the above experiments, no gender specific differences were observed in either Gaq-OE or in WT. We conclude that, in mice, increased expression of the Galphaq-protein induces alterations of myofibrillar function and energy consumption, which are also characteristics of human heart failure. This may result from a decreased phosphorylation of troponin I in Galphaq-OE.


Asunto(s)
Calcio/farmacología , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Fibras Musculares Esqueléticas/efectos de los fármacos , Octoxinol/farmacología , Troponina I/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Señalización del Calcio/efectos de los fármacos , Femenino , Queratolíticos/farmacología , Masculino , Ratones , Ratones Transgénicos , Contracción Muscular/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Fosforilación/efectos de los fármacos , Regulación hacia Arriba
15.
J Pharmacol Exp Ther ; 322(1): 222-7, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17409273

RESUMEN

Evidence is given that beta-blocker treatment differentially influences gene expression and up-regulation of beta(1)-adrenoceptors in human myocardium. Here, we investigate whether long-term treatment with carvedilol or metoprolol may functionally alter myofibrillar function in end-stage human heart failure. Investigations were performed in Triton X (1%, 4 degrees C, 20 h)-skinned fiber preparations of explanted hearts from patients undergoing heart transplantation due to idiopathic dilative cardiomyopathy. Five patients were not on beta-adrenoceptor blocker treatment (DCM_NBB), and 5 patients received either carvedilol (DCM_CAR) or metoprolol (DCM_MET). Nonfailing (NF) donor hearts (n = 5), which could not be transplanted due to technical reasons, were investigated for comparison. Ca(2+)-dependent tension (DT) development and actomyosin-ATPase activity (MYO) were measured and tension-dependent ATP consumption was calculated by the ratio of DT and MYO ("tension cost"). In addition, we measured the phosphorylation of troponin I (TNI) by back phosphorylation. Maximal DT and TNI phosphorylation were reduced, with myofibrillar Ca(2+) sensitivity of DT and MYO as well as tension cost being increased in DCM_NBB compared with NF. Metoprolol treatment restored TNI phosphorylation, decreased Ca(2+) sensitivity of tension development and of myosin-ATPase activity, but did not alter the tension-dependent ATP consumption. Carvedilol treatment improved maximal DT and significantly decreased tension-dependent ATP consumption without altering myofibrillar Ca(2+) sensitivity. TNI dephosphorylation was increased in patients treated with carvedilol. In conclusion, chronic beta-adrenoceptor blockade functionally alters myofibrillar function. The more economic cross-bridge cycling in patients under carvedilol treatment may provide an explanation for the efficacy of carvedilol in the treatment of chronic heart failure patients.


Asunto(s)
Antagonistas Adrenérgicos beta/farmacología , Calcio/metabolismo , Carbazoles/farmacología , Corazón/efectos de los fármacos , Miofibrillas/efectos de los fármacos , Propanolaminas/farmacología , Carvedilol , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Metoprolol/farmacología , Persona de Mediana Edad , Contracción Miocárdica/efectos de los fármacos , Miofibrillas/metabolismo , Miosinas/metabolismo , Octoxinol/farmacología , Fosforilación , Troponina I/metabolismo
16.
Oncogene ; 26(19): 2685-94, 2007 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-17072339

RESUMEN

The human c-rel proto-oncogene (REL) encodes a subunit of the nuclear factor-kappaB (NF-kappaB) transcription factor. In this report, we have identified an identical point mutation in two human B-cell lymphomas (follicular (FL) and mediastinal) that changes serine (Ser)525 (TCA) to proline (Pro) (CCA) within the REL transactivation domain. This mutation was not identified in a similarly sized cohort of healthy individuals. In the mediastinal B-cell lymphoma, the mutation in REL is of germ-line origin. In both tumors, the S525P mutant allele is over-represented. REL-S525P shows enhanced in vitro transforming activity in chicken spleen cells. REL-S525P has a reduced ability to activate the human manganese superoxide dismutase (MnSOD) promoter in A293 cells; however, the MnSOD protein shows increased expression in REL-S525P-transformed chicken spleen cells as compared to wild-type REL-transformed cells. Ser525 is a site for phosphorylation by IkappaB kinase (IKK) in vitro. The S525P mutation reduces IKKalpha- and tumor necrosis factor (TNF)alpha-stimulated transactivation by a GAL4-REL protein. Furthermore, REL-S525P-transformed chicken spleen cells are more resistant to TNFalpha-induced cell death than cells transformed by wild-type REL. These results suggest that the S525P mutation contributes to the development of human B-cell lymphomas by affecting an IKKalpha-regulated transactivation activity of REL.


Asunto(s)
Transformación Celular Viral , Quinasa I-kappa B/fisiología , Linfoma de Células B/genética , Mutación Puntual/genética , Proteínas Proto-Oncogénicas c-rel/genética , Secuencia de Aminoácidos , Animales , Western Blotting , Pollos , Ensayo de Cambio de Movilidad Electroforética , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Hibridación Fluorescente in Situ , Riñón/metabolismo , Luciferasas/metabolismo , Linfoma de Células B/metabolismo , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Neoplasias del Mediastino/genética , Neoplasias del Mediastino/metabolismo , Datos de Secuencia Molecular , FN-kappa B/genética , FN-kappa B/metabolismo , Fosforilación , Regiones Promotoras Genéticas/genética , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-rel/metabolismo , Homología de Secuencia de Aminoácido , Bazo/metabolismo , Bazo/virología , Activación Transcripcional , Factor de Necrosis Tumoral alfa/farmacología
17.
Leukemia ; 18(10): 1637-45, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15343348

RESUMEN

The clinically most suitable method for minimal residual disease (MRD) detection in chronic lymphocytic leukemia is still controversial. We prospectively compared MRD assessment in 158 blood samples of 74 patients with CLL after stem cell transplantation (SCT) using four-color flow cytometry (MRD flow) in parallel with consensus IgH-PCR and ASO IgH real-time PCR (ASO IgH RQ-PCR). In 25 out of 106 samples (23.6%) with a polyclonal consensus IgH-PCR pattern, MRD flow still detected CLL cells, proving higher sensitivity of flow cytometry over PCR-genescanning with consensus IgH-primers. Of 92 samples, 14 (15.2%) analyzed in parallel by MRD flow and by ASO IgH RQ-PCR were negative by our flow cytometric assay but positive by PCR, thus demonstrating superior sensitivity of RQ-PCR with ASO primers. Quantitative MRD levels measured by both methods correlated well (r=0.93). MRD detection by flow and ASO IgH RQ-PCR were equally suitable to monitor MRD kinetics after allogeneic SCT, but the PCR method detected impending relapses after autologous SCT earlier. An analysis of factors that influence sensitivity and specificity of flow cytometry for MRD detection allowed to devise further improvements of this technique.


Asunto(s)
Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/genética , Neoplasia Residual/diagnóstico , Trasplante de Células Madre , Adulto , Secuencia de Consenso , Femenino , Citometría de Flujo/métodos , Humanos , Cinética , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Linfocítica Crónica de Células B/terapia , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Sensibilidad y Especificidad , Trasplante Autólogo , Trasplante Homólogo
18.
Leukemia ; 18(4): 709-19, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14961040

RESUMEN

Current MRD studies in T-cell acute lymphoblastic leukemia (T-ALL) mainly use T-cell receptor gamma, delta and SIL-TAL1 gene rearrangements as MRD-PCR targets. However, low frequency or limited diversity of these markers restricts the number of evaluable patients, particularly because two markers are recommended for MRD monitoring. Hence, we developed a new strategy implementing the TCR beta (TCRB) locus for MRD quantification. The frequency and characteristics of complete and incomplete TCRB rearrangements were investigated in 53 childhood and 100 adult T-ALL patients using the BIOMED-2 multiplex PCR assay. Clonal rearrangements were identified in 92% both childhood and adult T-ALL (Vbeta-Dbeta-Jbeta rearrangements in 80%, Dbeta-Jbeta rearrangements in 53%). Comparative sequence analysis of 203 TCRB recombinations revealed preferential usage of the 'end-stage' segment Jbeta2.7 in childhood T-ALL (27%), whereas Jbeta2.3 was most frequently involved in adult T-ALL (24%). In complete rearrangements, three downstream Vbeta segments (19-1/20-1/21-1) were preferentially used. Subsequently, a TCRB real-time quantitative PCR assay to quantify MRD with 13 germline Jbeta primer/probe combinations and allele-specific oligonucleotides was developed and applied to 60 clonal TCRB rearrangements. The assay allowed the detection of one leukemic cell within at least 10(4) polyclonal cells in 93% of cases and will be of high value for future MRD studies.


Asunto(s)
Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Leucemia-Linfoma de Células T del Adulto/diagnóstico , Neoplasia Residual/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Adulto , Niño , Cartilla de ADN , Humanos , Leucemia-Linfoma de Células T del Adulto/genética , Neoplasia Residual/genética , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Sensibilidad y Especificidad
19.
Ann Hematol ; 81(10): 570-4, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12424538

RESUMEN

In acute lymphoblastic leukemia (ALL), treatment with granulocyte colony stimulating factor (G-CSF) during remission induction shortens granulocytopenia and may decrease morbidity due to infections. However, the optimal timing of G-CSF administration after chemotherapy is not known. In a prospective randomized multi-center study, adult ALL patients were treated with high-dose ARA-C [HDAC, 3 g/m(2) bid (1 g/m(2) bid for T-ALL) days 1-4] and mitoxantrone (MI 10 mg/m(2) days 3-5). They were randomized to receive recombinant human G-CSF (Lenograstim) 263 micro g/day SC starting either from day 12 (Group 1) or day 17 (Group 2). Fifty-five patients (41 male, 14 female) with a median age of 34 years (range: 18-55 years) were enrolled into the study; 50 patients were evaluable. The median duration of neutropenia <500/ micro l after HDAC/MI was 12 days (range: 7-22 days) in the early G-CSF Group 1 and also 12 days (range: 4-22 days) in the late G-CSF Group 2; this was shorter than in the historical control group (15 days, range: 4-43 days, n=46) where the patients received identical cytotoxic treatment without G-CSF. Seventeen infections were observed in 14 patients in Group 1 (47%) and 13 infections in 10 patients in Group 2 (50%) compared to 27 infections in 49 patients of the historical control (54%). In Group 1, the patients received a median of 11 injections with G-CSF (range: 7-22) compared to 7 injections (range: 4-19) in Group 2. The total administered dose of G-CSF in Group 2 was significantly reduced by 40% ( P<0.0001). The delayed start of G-CSF after HDAC/MI in ALL achieves the same clinical benefit compared to the earlier initiation of G-CSF. The reduction of treatment costs by reducing the total G-CSF dose may be important in future treatment with this hematopoietic growth factor.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/economía , Citarabina/administración & dosificación , Esquema de Medicación , Femenino , Hematopoyesis/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Neutropenia/prevención & control , Infecciones Oportunistas/prevención & control , Leucemia-Linfoma Linfoblástico de Células Precursoras/economía , Estudios Prospectivos , Resultado del Tratamiento
20.
Dtsch Med Wochenschr ; 127(43): 2253-8, 2002 Oct 25.
Artículo en Alemán | MEDLINE | ID: mdl-12397539

RESUMEN

BACKGROUND AND OBJECTIVE: Rituximab has shown a high activity in relapsed follicular lymphomas when given alone. Further on, phase-II-studies indicate that its addition to chemotherapy may improve the response rate substantially. However, so far, prospective randomized studies have not been available. PATIENTS AND METHODS: In 1998 the GLSG started a multicenter trial in patients with relapsed or refractory indolent lymphoma or mantle cell lymphoma. A fludarabine-containing regimen (FCM) was chosen for salvage therapy, with fludarabine 25 mg/m(2)/d 1-3, cyclophosphamide 200 mg/m(2) d 1-3 and mitoxantrone 8 mg/m(2) d 1. A total of four courses, every 4 weeks were given. Patients were prospectively randomized for FCM alone or the immunochemotherapy with R-FCM (375 mg/m(2) one day before FCM) RESULTS: About 147 randomized patients 93 had follicular, 40 mantle cell and 14 lymphoplasmocytic/-cytoid lymphoma. Statistical analysis was performed by sequential testing and indicated for 94 fully evaluable patients a significant advantage for the R-FCM-arm, with an overall response rate of 83 % as compared to 58%, when treated with FCM alone (CR: 35 % vs. 13 %). Similar improvements of remission rate were detected in the different lymphoma subgroups, especially in MCL (OR: 65 % vs. 33 %). Both treatment options were associated with hematological toxicities of grade III and IV, but well tolerated; infectious complications were rare, with no difference between the two treatment groups. CONCLUSION: This prospectively randomized trial demonstrates for the first time a significant improvement of the combined immunochemotherapy related to the remission rate in patients with relapsed or refractory indolent lymphoma.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma Folicular/tratamiento farmacológico , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Vidarabina/análogos & derivados , Adulto , Anciano , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales de Origen Murino , Antimetabolitos/administración & dosificación , Antineoplásicos/administración & dosificación , Terapia Combinada , Femenino , Humanos , Inmunosupresores/administración & dosificación , Inmunoterapia , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Mitoxantrona/administración & dosificación , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Rituximab , Factores de Tiempo , Vidarabina/administración & dosificación
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