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1.
mBio ; 10(5)2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615963

RESUMO

Proteogenomics combines proteomics, genomics, and transcriptomics and has considerably improved genome annotation in poorly investigated phylogenetic groups for which homology information is lacking. Furthermore, it can be advantageous when reinvestigating well-annotated genomes. Here, we applied an advanced proteogenomics approach, combining standard proteogenomics with peptide de novo sequencing, to refine annotation of the well-studied model fungus Sordaria macrospora We investigated samples from different developmental and physiological conditions, resulting in the detection of 104 so-far hidden proteins and annotation changes in 575 genes, including 389 splice site refinements. Significantly, our approach provides peptide-level evidence for 113 single-amino-acid variations and 15 C-terminal protein elongations originating from A-to-I RNA editing, a phenomenon recently detected in fungi. Coexpression and phylostratigraphic analysis of the refined proteome suggest that new functions in evolutionarily young genes correlate with distinct developmental stages. In conclusion, our advanced proteogenomics approach supports and promotes functional studies of fungal model systems.IMPORTANCE Next-generation sequencing techniques have considerably increased the number of completely sequenced eukaryotic genomes. These genomes are mostly automatically annotated, and ab initio gene prediction is commonly combined with homology-based search approaches and often supported by transcriptomic data. The latter in particular improve the prediction of intron splice sites and untranslated regions. However, correct prediction of translation initiation sites (TIS), alternative splice junctions, and protein-coding potential remains challenging. Here, we present an advanced proteogenomics approach, namely, the combination of proteogenomics and de novo peptide sequencing analysis, in conjunction with Blast2GO and phylostratigraphy. Using the model fungus Sordaria macrospora as an example, we provide a comprehensive view of the proteome that not only increases the functional understanding of this multicellular organism at different developmental stages but also immensely enhances the genome annotation quality.


Assuntos
Processamento Alternativo/genética , Genoma Fúngico/genética , Peptídeos/metabolismo , Proteogenômica/métodos , Anotação de Sequência Molecular , Filogenia
2.
Eukaryot Cell ; 9(6): 894-905, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20435701

RESUMO

Mating-type genes in fungi encode regulators of mating and sexual development. Heterothallic ascomycete species require different sets of mating-type genes to control nonself-recognition and mating of compatible partners of different mating types. Homothallic (self-fertile) species also carry mating-type genes in their genome that are essential for sexual development. To analyze the molecular basis of homothallism and the role of mating-type genes during fruiting-body development, we deleted each of the three genes, SmtA-1 (MAT1-1-1), SmtA-2 (MAT1-1-2), and SmtA-3 (MAT1-1-3), contained in the MAT1-1 part of the mating-type locus of the homothallic ascomycete species Sordaria macrospora. Phenotypic analysis of deletion mutants revealed that the PPF domain protein-encoding gene SmtA-2 is essential for sexual reproduction, whereas the alpha domain protein-encoding genes SmtA-1 and SmtA-3 play no role in fruiting-body development. By means of cross-species microarray analysis using Neurospora crassa oligonucleotide microarrays hybridized with S. macrospora targets and quantitative real-time PCR, we identified genes expressed under the control of SmtA-1 and SmtA-2. Both genes are involved in the regulation of gene expression, including that of pheromone genes.


Assuntos
Proteínas Fúngicas/genética , Genes Fúngicos Tipo Acasalamento , Sordariales/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Mutação , Fenótipo , Reação em Cadeia da Polimerase , Sordariales/crescimento & desenvolvimento
3.
Eur J Haematol ; 78(2): 93-101, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17313557

RESUMO

High-dose chemotherapy (HD-CT) with autologous stem cell transplantation is considered to be the treatment of choice for relapsed high-grade non-Hodgkin's lymphoma (NHL) and Hodgkin's lymphoma (HL) patients, but the optimal treatment has not yet been defined. We evaluated a salvage treatment regimen consisting of conventional cycles with ifosfamide, etoposide, cytarabine, and dexamethasone (IVAD) followed by two cycles of HD-CT consisting of cyclophosphamide, melphalan, and etoposide (CMV) with autologous stem cell support in patients with relapsed or refractory NHL (n = 59) and HL (n = 16). Response to IVAD was complete remission (CR) in 16 patients (21%), partial remission (PR) in 39 patients (52%), stable disease (SD) in 18 patients (24%), and progressive disease (PD) in two patients (2.7%). Of 70 patients treated with HD-CT, 41 patients (59%) showed a CR, 20 patients a PR (29%), eight patients a SD (11%), and one patient a PD (1.4%). The 5-yr overall survival for the entire group of patients was 29%, and for patients with NHL and HL 25%, and 38%, respectively. The respective event-free survival probabilities at 5 yr were 22%, 16%, and 31%. Seven treatment-related deaths due to septicemia (three), cardiac arrhythmia (one), pneumonia (one), pneumonitis (one), and toxic epidermal necrolysis (one) were observed. In multivariate analysis, an International Prognostic Index of > or = 2 and resistant disease to first-line chemotherapy were poor independent prognostic factors for the subgroup of patients with NHL. In conclusion, these results indicate that IVAD/CMV is feasible as a salvage therapy for lymphoma patients. This treatment is currently evaluated with the addition of rituximab.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma não Hodgkin/terapia , Linfoma/terapia , Transplante de Células-Tronco de Sangue Periférico , Terapia de Salvação , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Doenças da Medula Óssea/induzido quimicamente , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Citarabina/administração & dosagem , Citarabina/uso terapêutico , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Feminino , Seguimentos , Gastroenteropatias/induzido quimicamente , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/cirurgia , Doença de Hodgkin/terapia , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/uso terapêutico , Estimativa de Kaplan-Meier , Linfoma/tratamento farmacológico , Linfoma/cirurgia , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/cirurgia , Masculino , Melfalan/administração & dosagem , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Recidiva , Indução de Remissão , Sepse/etiologia , Sepse/mortalidade , Taxa de Sobrevida , Transplante Autólogo , Resultado do Tratamento
4.
Anticancer Res ; 26(1B): 479-84, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16739308

RESUMO

BACKGROUND: Anaemia is a common complication of chemotherapy (CT), including both non-platinum (Pt)-based as well as Pt-based CT. PATIENTS AND METHODS: Patients from three controlled trials with solid tumours receiving either Pt- or non-Pt-based CT, who had been randomised to epoetin beta treatment or standard care, were included in this meta-analysis (n=255, n=199, respectively), to see if epoetin beta was equally effective in both CT types. The primary endpoint was haemoglobin (Hb) change. Secondary end-points included transfusion requirement, adverse events (AEs), survival, time to tumour progression and thromboembolic events (TEEs). RESULTS: All patients responded rapidly to epoetin beta treatment, showing a median Hb increase of > or = 1 g/dl from baseline at week 4. A median Hb of 12.2, 12.5 and 11.8 g/dl was achieved in all patients, those receiving Pt-based CT and those receiving non-Pt-based CT, respectively, after 16 weeks of treatment. Transfusion risk reductions associated with epoetin beta treatment of 53% (p<0.0001), 61% (p<0.0001) and 26% (non significant) were observed for all patients, Pt- and non-Pt-based CT patients, respectively. Overall, for all three populations, there were no risks identified for tumour progression or overall survival. There was a statistically non-significant incidence of TEEs (5.9% versus 4.5%) and no marked differences were observed between groups for frequency or type of AEs reported. CONCLUSION: The type of CT has no impact on the ability of epoetin beta to rapidly increase Hb in patients with solid tumours and CT-induced anaemia.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/administração & dosagem , Neoplasias/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Anemia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Feminino , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Recombinantes
5.
Mol Genet Genomics ; 275(5): 492-503, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16482473

RESUMO

Sordaria macrospora is a homothallic ascomycete which is able to form fertile fruiting bodies without a mating partner. To analyze the molecular basis of homothallism and the role of mating products during fruiting body development, we have deleted the mating type gene Smta-1 encoding a high-mobility group domain (HMG) protein. The DeltaSmta-1 deletion strain is morphologically wild type during vegetative growth, but it is unable to produce perithecia or ascospores. To identify genes expressed under control of Smta-1, we performed a cross-species microarray analysis using Neurospora crassa cDNA microarrays hybridized with S. macrospora targets. We identified 107 genes that are more than twofold up- or down-regulated in the mutant. Functional classification revealed that 81 genes have homologues with known or putative functions. Comparison of array data from DeltaSmta-1 with those from three phenotypically similar mutants revealed that only a limited set of ten genes is deregulated in all mutants. Remarkably, the ppg2 gene encoding a putative lipopeptide pheromone is 500-fold down-regulated in the DeltaSmta-1 mutant while in all other sterile mutants this gene is up-regulated.


Assuntos
Perfilação da Expressão Gênica , Genes Fúngicos Tipo Acasalamento , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Sordariales/genética , Deleção de Genes , Neurospora crassa/genética , Fenótipo , Reprodução , Sordariales/crescimento & desenvolvimento , Sordariales/fisiologia
7.
Ann Hematol ; 84(2): 110-4, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15340761

RESUMO

Hemolytic uremic syndrome (HUS) has been described following the administration of multiple antineoplastic agents, most notably mitomycin C. More recently, several cases of gemcitabine-induced HUS have been observed with the overall incidence of gemcitabine-induced HUS estimated at 0.015-0.25%. We here report on four patients who developed HUS following gemcitabine therapy at our institution within the last year (incidence 1.4%). All these patients had advanced-stage disease, were heavily pretreated, and received prolonged gemcitabine application, suggesting that in this subgroup of patients HUS may be more frequently encountered than documented so far.


Assuntos
Desoxicitidina/análogos & derivados , Desoxicitidina/efeitos adversos , Síndrome Hemolítico-Urêmica/induzido quimicamente , Adenocarcinoma/complicações , Adenocarcinoma/tratamento farmacológico , Adulto , Antimetabólitos Antineoplásicos/efeitos adversos , Progressão da Doença , Evolução Fatal , Feminino , Humanos , Incidência , Linfoma/complicações , Linfoma/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Gencitabina
8.
Eur J Haematol ; 74(1): 40-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15613105

RESUMO

The present study aimed to evaluate the side-effects and efficacy of thalidomide in combination with an anthracycline-containing chemotherapy regimen in previously untreated myeloma patients. Thalidomide (400 mg/d) was combined with bolus injections of vincristine and epirubicin and oral dexamethasone (VED). Chemotherapy cycles were repeated every 3 wk until no further reduction in myeloma protein was observed, whereas the treatment with thalidomide was continued until disease progression. Thirty-one patients were enrolled, 12 patients were exclusively treated with thalidomide in combination with VED and 19 patients additionally received high-dose melphalan, for consolidation. Adverse events and response to therapy were assessed prior to treatment with high-dose chemotherapy. Response to thalidomide combined with VED was complete remission in six patients (19%), partial remission in 19 patients (61%), stable disease in five patients (16%), and progressive disease in one patient (3.2%). Grade 3 and 4 adverse events consisted of leukocytopenia in 10 patients (32%), and thrombocytopenia and anemia in one patient each (3.2%). Neutropenic infections grade 3 and 4 occurred in seven (23%) and three patients (9.7%), respectively, including two patients (6.5%) who died from septic shock. Deep vein thrombosis occurred in eight patients (26%), constipation in 20 patients (65%), and polyneuropathy in 20 patients (65%). The probability of event-free survival and overall survival in the whole group of patients at 36 months were 26 and 62%, respectively. In conclusion, the combination of thalidomide with VED appears to be highly effective in previously untreated patients with multiple myeloma, but it is associated with a high rate of thrombotic events, polyneuropathy, and neutropenic infections.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Talidomida/administração & dosagem , Adulto , Idoso , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/efeitos adversos , Dexametasona/administração & dosagem , Epirubicina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Talidomida/efeitos adversos , Vincristina/administração & dosagem
9.
Eur J Nucl Med Mol Imaging ; 31(3): 325-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14647988

RESUMO

The aim of this study was to evaluate the clinical significance of combined fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) in patients with lymphoma, and to compare the FDG-PET/CT staging results with those of FDG-PET and CT alone. Twenty-seven patients were studied. Each patient had clinical follow-up for >12 months and entered complete follow-up evaluation. Patient-based evaluation showed a sensitivity of 78% for CT alone, 86% for FDG-PET alone, 93% for CT and FDG-PET read side by side, and 93% for combined FDG-PET/CT imaging. Region-based evaluation showed a sensitivity for regional lymph node involvement of 61%, 78%, 91% and 96% respectively. FDG-PET/CT imaging is superior to CT alone ( P=0.02) and has additional benefit over FDG-PET alone due to exact anatomical localisation. We conclude that FDG-PET/CT imaging is accurate in re-staging lymphoma and offers advantages over separate FDG-PET and CT imaging.


Assuntos
Fluordesoxiglucose F18 , Doença de Hodgkin/diagnóstico por imagem , Aumento da Imagem/métodos , Linfoma não Hodgkin/diagnóstico por imagem , Técnica de Subtração , Adulto , Idoso , Feminino , Doença de Hodgkin/patologia , Humanos , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Prognóstico , Radiografia , Cintilografia , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
10.
Ann Hematol ; 82 Suppl 2: S105-17, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-13680173

RESUMO

Cytostatic chemotherapy of hematological malignancies is often complicated by neutropenia, which increases the risk of infections, especially if the neutrophil count is below 500/microl. Frequently, fever is the first, and in most patients the only, sign of an infection. Unexplained fever is defined as follows: temperature of >/=38.3 degrees C or >/=38.0 degrees C for at least 1 h, or measured twice within 12 h, if the neutrophil count is <500/microl or <1000/microl with predicted decline to 500/microl. Different risk categories can be identified according to the duration of neutropenia: low risk /=10 days. An empirical mono- or duotherapy with antipseudomonal and antistreptococcal agents should be initiated immediately. In the low risk patient group, oral therapy with cipro-, levo-, or ofloxacin combined with amoxicillin/clavulanic acid is permissible. For standard and high risk patients, monotherapy can be carried out with either ceftazidime, cefepime, piperacillin with tazobactam or a carbapenem. In duotherapy, a single dose of an aminoglycoside is combined with acylaminopenicillin or a cephalosporin of the third or fourth generation. The addition of glycopeptides in empirical therapy should only be considered in the presence of severe mucositis, or if a catheter-associated infection is suspected. If fever persists after 72-96 h of first-line therapy with antibiotics, the regimen should be modified (with the exception of e.g. coagulase-negative staphylococci infections, because these infections take longer to respond). Intermediate risk patients should additionally receive an aminoglycoside after monotherapy (penicillin or a cephalosporin). If a carbapenem was administered for monotherapy, this can be followed by a quinolone and/or a glycopeptide. In the high risk group, the same modifications should be made as in the intermediate risk group but with additional systemic antifungal treatment. In the presence of unexplained fever, fluconazole can be administered at first, but if this fails, amphotericin B (conventional or liposomal), itraconazole, voriconazole or caspofungin should be started. After defervescence to <38 degrees C, treatment should be continued for 7 days if the neutrophil count is <1000/microl, and for 2 days if the neutrophil count is >1000/microl.


Assuntos
Antibacterianos/uso terapêutico , Febre de Causa Desconhecida/complicações , Febre de Causa Desconhecida/tratamento farmacológico , Neutropenia/complicações , Humanos
11.
Ann Oncol ; 14 Suppl 1: i29-36, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12736228

RESUMO

Various chemotherapy regimens, combined with recombinant human granulocyte colony-stimulating factor(rhG-CSF) or recombinant granulocyte-macrophage CSF (rhGM-CSF) are used in cancer patients to mobilize and collect peripheral blood stem cells (PBSC). In this retrospective study, we evaluated and compared the efficacy of such regimens in 262 patients with different types of malignant diseases. The following chemotherapy regimens were applied: ifosfamide-etoposide-cisplatin or bleomycin (n = 96; mainly patients with testicular cancer); ifosfamide-etoposide plus or minus cytosine arabinoside (Ara-C) or vincristine (VCR)(n = 52; mainly patients with lymphoma); cyclophosphamide-anthracycline (n = 53; mainly patients with breast cancer); intermediate to high dose (ID-HD) cyclophosphamide (n = 37; mainly patients with breast or ovarian cancer. or multiple myeloma; and others (n = 24). rhG-CSF or rhGM-CSF, each at an average daily dose of 5 microg/kg body weight, were used in 166 and 96 patients, respectively. The study evaluated and compared the efficacy of these two cytokines. In patients receiving rhG-CSF, CD34+ cells could be collected earlier (median: day 14 versus day 16) and there was a significantly higher white blood cell count (WBC)(median 11,350 versus 5550/microl) and CD34+ cell count (median 88 versus 43/microl) at the start of apheresis, and a significantly higher CD34+ cell yield (median 7.4 x 10(6) versus 4.6 x 10(6)/kg) than in patients who receivedrhGM-CSF. Among the various chemotherapeutic regimens used, each combined with rhG-CSF, ifosfamide-etoposide plus or minus Ara-C or VCR mobilized a significantly higher number of CD34+ cells (median 119/microl) and produced a significantly higher harvest of these cells (median 13 x 10(6)/kg) than cyclophosphamide-anthracycline (median 87/microl and 7 x 10(6)/kg, respectively) or ID-HD cyclophosphamide (median 59/microl and 5 x I 0(6)/kg, respectively). Ifosfamide-etoposide plus or minus Ara-C or VCR was also superior to ifosfamide-etoposide-cisplatin or bleomycin (median 78/microl and 9 x 10(6)/kg, respectively), but at borderline significance. The outcome of PBSC mobilization and collection appeared to be negatively influenced by the number of relapses before the current salvage treatment. These data indicate that mobilization and collection of PBSCstrongly depend on the type of hematopoietic growth factor and chemotherapeutic regimen used. The data further show rhG-CSF is a more effective growth factor than rhGM-CSF and ifosfamide-etoposide-based regimens, particularly ifosfamide-etoposide plus or minus Ara-C or VCR, are highly effective regimens in mobilizing and collecting CD34+ cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fatores de Crescimento de Células Hematopoéticas/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Neoplasias/tratamento farmacológico , Transplante de Células-Tronco de Sangue Periférico/métodos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fatores de Crescimento de Células Hematopoéticas/sangue , Humanos , Modelos Logísticos , Neoplasias/sangue , Neoplasias/cirurgia , Valor Preditivo dos Testes , Proteínas Recombinantes , Estudos Retrospectivos
12.
Genetics ; 157(3): 1057-65, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238394

RESUMO

In an effort to determine genes that are expressed in mycelial cultures of Neurospora crassa over the course of the circadian day, we have sequenced 13,000 cDNA clones from two time-of-day-specific libraries (morning and evening library) generating approximately 20,000 sequences. Contig analysis allowed the identification of 445 unique expressed sequence tags (ESTs) and 986 ESTs present in multiple cDNA clones. For approximately 50% of the sequences (710 of 1431), significant matches to sequences in the National Center for Biotechnology Information database (of known or unknown function) were detected. About 50% of the ESTs (721 of 1431) showed no similarity to previously identified genes. We hybridized Northern blots with probes derived from 26 clones chosen from contigs identified by multiple cDNA clones and EST sequences. Using these sequences, the representation of genes among the morning and evening sequences, respectively, in most cases does not reflect their expression patterns over the course of the day. Nevertheless, we were able to identify four new clock-controlled genes. On the basis of these data we predict that a significant proportion of the expressed Neurospora genes may be regulated by the circadian clock. The mRNA levels of all four genes peak in the subjective morning as is the case with previously identified ccgs.


Assuntos
Etiquetas de Sequências Expressas , Biblioteca Gênica , Neurospora crassa/genética , Northern Blotting , Ritmo Circadiano/genética , Mapeamento de Sequências Contíguas , DNA Complementar/metabolismo , Bases de Dados Factuais , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Software , Fatores de Tempo
13.
Curr Genet ; 37(3): 189-93, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10794176

RESUMO

ATP citrate lyase (ACL) catalyzes the formation of cytosolic acetyl-CoA, which is mainly used for the biosynthesis of fatty acids and sterols. In this paper, we show for the first time that in filamentous fungi two different subunits of ACL are encoded by two separate genes. This is in contrast to animals where ACL is encoded by a single gene. Data are presented on acl genes from the filamentous fungi Sordaria macrospora and Gibberella pulicaris. In S. macrospora, both genes, acl1 and acl2, are clustered within a region of 10 kb and are divergently transcribed.


Assuntos
ATP Citrato (pro-S)-Liase/genética , Proteínas Fúngicas/genética , Genes Fúngicos/genética , ATP Citrato (pro-S)-Liase/química , Sequência de Aminoácidos , Animais , Northern Blotting , DNA Fúngico/química , DNA Fúngico/genética , Proteínas Fúngicas/química , Gibberella/enzimologia , Gibberella/genética , Isoenzimas/química , Isoenzimas/genética , Dados de Sequência Molecular , Família Multigênica , Fases de Leitura Aberta , RNA Fúngico/genética , RNA Fúngico/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Sordariales/enzimologia , Sordariales/genética
14.
Exp Hematol ; 27(11): 1621-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10560909

RESUMO

In an attempt to define the relation among anemia, tumor mass, and proliferative activity of tumor cells in vivo, we measured the proportion and cell cycle distribution of erythropoietic cells and myeloma cells in the bone marrow of patients with multiple myeloma using four-parameter flow cytometry. Forty-three bone marrow samples from 33 patients with stage II or III disease and normal renal function at diagnosis (n = 9), in partial remission (n = 9), and in progression or relapse after chemotherapy (n = 25) were evaluated. Early and late erythropoietic cells were discriminated based on published light scatter properties in combination with CD71 expression. Myeloma cells were detected by exploiting their strong CD38 positivity and light scatter characteristics. Cell cycle distribution of the three cell populations was determined by propidium iodine staining. In the whole group of patients, hemoglobin (Hb) concentration was inversely correlated with beta2-microglob-ulin (p = 0.03), percentage of marrow CD38++ cells (p = 0.008), and percentage of CD38(++) cells in S phase (S-CD38++; p < 0.001). Partial correlation analysis revealed S-CD38++ to be the only independent predictor of Hb concentration (p < 0.001). No correlation was found between Hb concentration and the S-phase fraction of erythropoietic cells. In the subgroup of patients with moderate to severe anemia, defined as Hb concentration <11 g/dL, Hb level correlated negatively only with S-CD38++ (p < 0.001) but not with beta2-microglobulin and percentage of marrow CD38++ cells. In addition, Hb and the S-phase proportion of early erythropoietic cells correlated positively (p = 0.029). The strong inverse correlation between Hb concentration and percentage of myeloma cells in S phase suggests that in multiple myeloma, tumor proliferative activity may have a more important impact on the development of anemia than tumor mass. The S-phase fraction of tumor cells appears to be the most important pathogenic factor, especially in anemic patients. In these patients, the positive relation between Hb concentration and the S-phase fraction of erythropoietic progenitors indicates that development of anemia is associated with inhibition of erythropoiesis.


Assuntos
Anemia/patologia , Antígenos CD , Mieloma Múltiplo/patologia , Fase S/fisiologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Antígenos de Diferenciação , Ciclo Celular/fisiologia , Fracionamento Celular , Células Precursoras Eritroides/patologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Glicoproteínas de Membrana , NAD+ Nucleosidase , Propídio , Coloração e Rotulagem , Estatísticas não Paramétricas
15.
J Clin Oncol ; 17(12): 3786-92, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10577850

RESUMO

PURPOSE: A multicenter phase II trial was conducted to evaluate the efficacy and toxicity of gemcitabine in patients with relapsed or refractory aggressive non-Hodgkin's lymphomas (NHL). PATIENTS AND METHODS: Thirty-one patients with B-cell intermediate or high-grade NHL (Working Formulation) were enrolled onto the study. The median age was 61 years, with a Karnofsky performance status of

Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Linfoma não Hodgkin/tratamento farmacológico , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Gencitabina
17.
Mol Cell Biol ; 19(1): 450-60, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9858569

RESUMO

During sexual development, mycelial cells from most filamentous fungi differentiate into typical fruiting bodies. Here, we describe the isolation and characterization of the Sordaria macrospora developmental mutant per5, which exhibits a sterile phenotype with defects in fruiting body maturation. Cytological investigations revealed that the mutant strain forms only ascus precursors without any mature spores. Using an indexed cosmid library, we were able to complement the mutant to fertility by DNA-mediated transformation. A single cosmid clone, carrying a 3.5-kb region able to complement the mutant phenotype, has been identified. Sequencing of the 3.5-kb region revealed an open reading frame of 2.1 kb interrupted by a 66-bp intron. The predicted polypeptide (674 amino acids) shows significant homology to eukaryotic ATP citrate lyases (ACLs), with 62 to 65% amino acid identity, and the gene was named acl1. The molecular mass of the S. macrospora ACL1 polypeptide is 73 kDa, as was verified by Western blot analysis with a hemagglutinin (HA) epitope-tagged ACL1 polypeptide. Immunological in situ detection of the HA-tagged polypeptide demonstrated that ACL is located within the cytosol. Sequencing of the mutant acl1 gene revealed a 1-nucleotide transition within the coding region, resulting in an amino acid substitution within the predicted polypeptide. Further evidence that ACL1 is essential for fruiting body maturation comes from experiments in which truncated and mutated versions of the acl1 gene were used for transformation. None of these copies was able to reconstitute the fertile phenotype in transformed per5 recipient strains. ACLs are usually involved in the formation of cytosolic acetyl coenzyme A (acetyl-CoA), which is used for the biosynthesis of fatty acids and sterols. Protein extracts from the mutant strain showed a drastic reduction in enzymatic activity compared to values obtained from the wild-type strain. Investigation of the time course of ACL expression suggests that ACL is specifically induced at the beginning of the sexual cycle and produces acetyl-CoA, which most probably is a prerequisite for fruiting body formation during later stages of sexual development. We discuss the contribution of ACL activity to the life cycle of S. macrospora.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Ascomicetos/citologia , Ascomicetos/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Cosmídeos , DNA Complementar , DNA Fúngico , Teste de Complementação Genética , Humanos , Dados de Sequência Molecular , Mutação , Peptídeos/análise , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
19.
Med Oncol ; 15 Suppl 1: S19-28, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9785333

RESUMO

Patients with cancer frequently develop anaemia, due either to the malignant disease itself or to its treatment. Various factors, including the type of malignancy and the type and intensity of chemotherapy, influence the prevalence of anaemia and the need for transfusions. Among patients with solid tumours, those with lung cancer and ovarian cancer are reported to have the highest frequency of anaemia (52% and 51%, respectively) and the highest rate of transfusion requirements (28% and 25%, respectively). Patients with a low level of haemoglobin (Hb) (10-12 g/dl) at the start of chemotherapy are particularly at risk of developing anaemia and requiring transfusions. Similarly, patients treated with platinum-based regimens more often develop anaemia and need transfusions. The frequency of transfusion requirements in these patients can amount to 47%-100%, depending on the cumulative dose of platinum and other risk factors, such as advanced age, loss of body weight before treatment, advanced disease stage, and particularly a low primary level of Hb (11 g/dl) and a decrease in Hb level (1-2 g/dl) after the first cycle of treatment. The causative mechanism of platinum-induced anaemia is reported to be, beside myelosuppression, a deficient production of erythropoietin (EPO) resulting from drug-induced renal tubular damage. In a number of randomised and nonrandomised studies, recombinant human (rh) EPO has been shown to be effective in the treatment of cancer-related anaemia (CRA) and in the prevention and treatment of chemotherapy-induced anaemia. An appropriate dose of rhEPO for the start of treatment is 150 U/kg given subcutaneously three times per week (t.i.w.). The response rate of anaemia ranges from 40% to 85%. rhEPO is well tolerated, but the cost of treatment requires patient selection and parameters predicting response as early as possible after the start of treatment. Appropriate groups of patients for treatment with rhEPO are those with an Hb level of < 10 g/dl and those with a higher Hb level, but symptomatic anaemia. Other groups are patients who are going to receive chemotherapy and have a low primary level of Hb (10-12 g/dl) and patients who receive platinum-based chemotherapy and have experienced a marked decrease in their Hb level (1-2 g/dl) from baseline to the second cycle of treatment. These patients have a high risk of becoming anaemic and requiring transfusions during chemotherapy. In anaemic cancer patients treated with rhEPO, an early indicator of response is an increase in Hb level of at least 0.5 g/dl in patients not receiving chemotherapy and 1 g/dl in those receiving chemotherapy, combined with an increase in reticulocyte count of at least 40,000 cells/microliter after 2 weeks of treatment in the first group of patients and after 4 weeks in the second.


Assuntos
Anemia/etiologia , Anemia/terapia , Antineoplásicos/efeitos adversos , Transfusão de Sangue , Eritropoetina/uso terapêutico , Neoplasias/complicações , Anemia/induzido quimicamente , Relação Dose-Resposta a Droga , Humanos , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Recombinantes
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