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1.
Ann Hematol ; 102(6): 1383-1393, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37039874

RESUMO

Acute myeloid leukemia (AML) can lead to life-threatening complications that may require intensive care unit (ICU) management. It has been advocated that early preemptive (ePE) ICU admission, before the onset of organ failure, could benefit some high-risk patients such as those with hyperleukocytosis. The aim of this study was to retrospectively analyze the outcome of newly diagnosed AML patients who required ICU admission in five academic centers with a special focus on patients with an ePE admission strategy, i.e., those transferred to the ICU without any organ failure (modified SOFA score ≤ 2 [omitting thrombocytopenia] and no life-sustaining intervention in the first 24 h following ICU admission) before the start of induction therapy. Between January 2017 and December 2019, 428 patients were included among which 101 were admitted to the ICU. Among patients requiring life-sustaining interventions (n = 83), 18 (22%) died while in the ICU but ICU survivors had the same survival as those not admitted to the ICU. Patients with an ePE admission (n = 18) had more comorbidities and high-risk disease features such as hyperleukocytosis but required no life-sustaining interventions while in the ICU. In a subgroup analysis of patients with hyperleukocytosis ≥ 50 G/l at diagnosis (n = 85), patients not admitted to the ICU and those admitted with an ePE strategy had similar outcomes. This study provides encouraging results about ICU outcome in AML patients during induction therapy but the potential benefit of an ePE strategy must be confirmed prospectively.


Assuntos
Leucemia Mieloide Aguda , Humanos , Estudos Retrospectivos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/epidemiologia , Leucemia Mieloide Aguda/terapia , Hospitalização , Unidades de Terapia Intensiva , Comorbidade
2.
J Antimicrob Chemother ; 77(9): 2546-2556, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35748614

RESUMO

BACKGROUND: Early antibiotic discontinuation according to the Fourth European Conference on Infections in Leukaemia (ECIL-4) recommendations is not systematically applied in high-risk neutropenic patients with haematological malignancies. METHODS: A retrospective multicentre observational study was conducted over 2 years to evaluate the safety of early antibiotic discontinuation for fever of unknown origin (FUO) during neutropenia after induction chemotherapy or HSCT, in comparison with a historical cohort. We used Cox proportional hazards models, censored on neutropenia resolution, to analyse factors associated with febrile recurrence. RESULTS: Among 147 included patients in the ECIL-4 cohort, mainly diagnosed with acute leukaemia (n = 104, 71%), antibiotics were discontinued during 170 post-chemotherapy neutropenic episodes. In comparison with the historical cohort of 178 episodes of neutropenia without antibiotic discontinuation, no significant differences were observed regarding febrile recurrences [71.2% (121/170) versus 71.3% (127/178), P = 0.97], admission in ICUs [6.5% (11/170) versus 11.2% (20/178), P = 0.17], septic shock [0.6% (1/170) versus 3.9% (7/178), P = 0.07] and 30 day mortality [1.4% (2/147) versus 2.7% (4/150), P = 0.084]. In the ECIL-4 cohort, the rate of bacteraemia in case of febrile recurrence was higher [27.1% (46/170) versus 11.8% (21/178), P < 0.01] and antibiotic consumption was significantly lower (15.5 versus 19.9 days, P < 0.001). After early antibiotic discontinuation according to ECIL-4 recommendations, enterocolitis was associated with febrile recurrence [HR = 2.31 (95% CI = 1.4-3.8), P < 0.001] and stage III-IV oral mucositis with bacteraemia [HR = 2.26 (95% CI = 1.22-4.2), P = 0.01]. CONCLUSIONS: After an FUO episode in high-risk neutropenia, compliance with ECIL-4 recommendations for early antibiotic discontinuation appears to be safe and mucosal damage was associated with febrile recurrence and bacteraemia. Prospective interventional studies are warranted to assess this strategy in high-risk neutropenic patients.


Assuntos
Bacteriemia , Febre de Causa Desconhecida , Neoplasias Hematológicas , Leucemia Mieloide Aguda , Neoplasias , Neutropenia , Antibacterianos/efeitos adversos , Bacteriemia/complicações , Bacteriemia/tratamento farmacológico , Febre de Causa Desconhecida/induzido quimicamente , Febre de Causa Desconhecida/complicações , Febre de Causa Desconhecida/tratamento farmacológico , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Leucemia Mieloide Aguda/complicações , Neoplasias/complicações , Neutropenia/induzido quimicamente , Neutropenia/complicações , Neutropenia/tratamento farmacológico , Estudos Prospectivos
3.
Proc Natl Acad Sci U S A ; 116(13): 6063-6068, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30850540

RESUMO

Over the last two decades, the number of gene/protein sequences gleaned from sequencing projects of individual genomes and environmental DNA has grown exponentially. Only a tiny fraction of these predicted proteins has been experimentally characterized, and the function of most proteins remains hypothetical or only predicted based on sequence similarity. Despite the development of postgenomic methods, such as transcriptomics, proteomics, and metabolomics, the assignment of function to protein sequences remains one of the main challenges in modern biology. As in all classes of proteins, the growing number of predicted carbohydrate-active enzymes (CAZymes) has not been accompanied by a systematic and accurate attribution of function. Taking advantage of the CAZy database, which groups CAZymes into families and subfamilies based on amino acid similarities, we recombinantly produced 564 proteins selected from subfamilies without any biochemically characterized representatives, from distant relatives of characterized enzymes and from nonclassified proteins that show little similarity with known CAZymes. Screening these proteins for activity on a wide collection of carbohydrate substrates led to the discovery of 13 CAZyme families (two of which were also discovered by others during the course of our work), revealed three previously unknown substrate specificities, and assigned a function to 25 subfamilies.


Assuntos
Metabolismo dos Carboidratos , Enzimas/genética , Análise de Sequência de Proteína , Sequência de Aminoácidos , Animais , Metabolismo dos Carboidratos/genética , Enzimas/metabolismo , Genômica/métodos , Humanos , Polissacarídeos/metabolismo , Análise de Sequência de DNA , Relação Estrutura-Atividade
4.
Trends Biochem Sci ; 41(7): 633-645, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27211037

RESUMO

Lignocellulose, the most abundant renewable carbon source on earth, is the logical candidate to replace fossil carbon as the major biofuel raw material. Nevertheless, the technologies needed to convert lignocellulose into soluble products that can then be utilized by the chemical or fuel industries face several challenges. Enzymatic hydrolysis is of major importance, and we review the progress made in fungal enzyme technology over the past few years with major emphasis on (i) the enzymes needed for the conversion of polysaccharides (cellulose and hemicellulose) into soluble products, (ii) the potential uses of lignin degradation products, and (iii) current progress and bottlenecks for the use of the soluble lignocellulose derivatives in emerging biorefineries.


Assuntos
Biocombustíveis , Biomassa , Enzimas/metabolismo , Fungos/enzimologia , Lignina/metabolismo , Hidrólise , Lignina/química
5.
Nat Chem Biol ; 14(3): 306-310, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29377002

RESUMO

Wood biomass is the most abundant feedstock envisioned for the development of modern biorefineries. However, the cost-effective conversion of this form of biomass into commodity products is limited by its resistance to enzymatic degradation. Here we describe a new family of fungal lytic polysaccharide monooxygenases (LPMOs) prevalent among white-rot and brown-rot basidiomycetes that is active on xylans-a recalcitrant polysaccharide abundant in wood biomass. Two AA14 LPMO members from the white-rot fungus Pycnoporus coccineus substantially increase the efficiency of wood saccharification through oxidative cleavage of highly refractory xylan-coated cellulose fibers. The discovery of this unique enzyme activity advances our knowledge on the degradation of woody biomass in nature and offers an innovative solution for improving enzyme cocktails for biorefinery applications.


Assuntos
Basidiomycota/enzimologia , Biomassa , Oxigenases de Função Mista/química , Polissacarídeos/química , Madeira/microbiologia , Biodegradação Ambiental , Biotecnologia/economia , Biotecnologia/métodos , Celulose/química , Biologia Computacional , Análise Custo-Benefício , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Genômica , Glicosilação , Oxigênio/química , Filogenia , Especificidade por Substrato , Transcriptoma , Xilanos/química
6.
Org Biomol Chem ; 14(1): 314-22, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26567779

RESUMO

The enzymatic digestion of the main components of lignocellulosic biomass, including plant cell wall mannans, constitutes a fundamental step in the renewable biofuel production, with great potential benefit in the industrial field. Despite several reports of X-ray structures of glycoside hydrolases, how polysaccharides are specifically recognized and accommodated in the enzymes binding site still remains a pivotal matter of research. Within this frame, NMR spectroscopic techniques provide key binding information, complementing and/or enhancing the structural view by X-ray crystallography. Here we provide deep insights into the binding mode of two endo-ß-1,4 mannanases from the coprophilous ascomycete Podospora anserina, PaMan26A and PaMan5A, involved in the hydrolysis of plant cell wall mannans and heteromannans. The investigation at a molecular level of the interaction between the wild-type enzymes and inactive mutants with manno-oligosaccharides, revealed a different mode of action among the two glycoside hydrolases most likely due to the presence of the additional and peculiar -4 subsite in the PaMan26A binding pocket.


Assuntos
Manosidases/química , Manosidases/classificação , Sítios de Ligação , Configuração de Carboidratos , Espectroscopia de Ressonância Magnética , Manosidases/metabolismo , Modelos Moleculares , Podospora/enzimologia
7.
Appl Microbiol Biotechnol ; 100(2): 697-706, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26452496

RESUMO

The discovery of novel fungal lignocellulolytic enzymes is essential to improve the breakdown of plant biomass for the production of second-generation biofuels or biobased materials in green biorefineries. We previously reported that Ustilago maydis grown on maize secreted a diverse set of lignocellulose-acting enzymes including hemicellulases and putative oxidoreductases. One of the most abundant proteins of the secretome was a putative glucose-methanol-choline (GMC) oxidoreductase. The phylogenetic prediction of its function was hampered by the few characterized members within its clade. Therefore, we cloned the gene and produced the recombinant protein to high yield in Pichia pastoris. Functional screening using a library of substrates revealed that this enzyme was able to oxidize several aromatic alcohols. Of the tested aryl-alcohols, the highest oxidation rate was obtained with 4-anisyl alcohol. Oxygen, 1,4-benzoquinone, and 2,6-dichloroindophenol can serve as electron acceptors. This GMC oxidoreductase displays the characteristics of an aryl-alcohol oxidase (E.C.1.1.3.7), which is suggested to act on the lignin fraction in biomass.


Assuntos
Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Lignina/metabolismo , Ustilago/enzimologia , 2,6-Dicloroindofenol/metabolismo , Benzoquinonas/metabolismo , Biomassa , Transporte de Elétrons , Oxigênio/metabolismo , Filogenia , Pichia/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ustilago/metabolismo
8.
Genes Chromosomes Cancer ; 54(10): 595-605, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26252834

RESUMO

We report five chronic myeloid leukaemia (CML) patients in whom we identified and characterized undescribed BCR-ABL1 fusion transcripts. We investigated the precise features of the molecular rearrangements and the minimal residual disease follow-up for these five patients. Three resulted from new rearrangements between the BCR and ABL1 sequences (the breakpoints being located within BCR exon 13 in two cases and within BCR exon 18 in one case). The other two cases revealed a complex e8-[ins]-a2 fusion transcript involving a third partner gene, PRDM12 and SPECC1L, respectively. Moreover, single nucleotide polymorphism-array analysis performed in the latter two cases showed copy number alterations shared by the two patients, thus identifying genes that were deleted during rearrangement and suggesting their potential role in CML pathogenesis. Interestingly, we highlight that the prognosis of alterations, such as the presence of an e8a2 transcript or the deletion of various genes, which have been controversial, may be definitively erased by the introduction of tyrosine kinase inhibitors (TKIs).


Assuntos
Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Am J Hematol ; 90(11): 986-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26214580

RESUMO

Central nervous system (CNS) thrombotic events are a well-known complication of acute lymphoblastic leukemia (ALL) induction therapy, especially with treatments including l-asparaginase (l-ASP). Data on risk factors and clinical evolution is still lacking in adult patients. We report on the clinical evolution of 22 CNS venous thrombosis cases occurring in 708 adults treated for ALL or lymphoblastic lymphoma (LL) with the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-induction protocol, which included eight L-ASP (6,000 IU/m(2) ) infusions. The prevalence of CNS thrombosis was 3.1%. CNS thrombosis occurred after a median of 18 days (range: 11-31) when patients had received a median of three l-ASP injections (range: 2-7). Patients with CNS thrombosis exhibited a median antithrombin (AT) nadir of 47.5% (range: 36-67%) at Day 17 (range: D3-D28), and 95% of them exhibited AT levels lower than 60%. There were no evident increase in hereditary thrombotic risk factors prevalence, and thrombosis occurred despite heparin prophylaxis which was performed in 90% of patients. Acquired AT deficiency was frequently detected in patients with l-ASP-based therapy, and patients with CNS thrombosis received AT prophylaxis (45%) less frequently than patients without CNS thrombosis (83%), P = 0.0002). CNS thrombosis was lethal in 5% of patients, while 20% had persistent sequelae. One patient received all planned l-ASP infusions without recurrence of CNS thrombotic whereas l-ASP injections were discontinued in 20 patients during the management of thrombosis without a significant impact on overall survival (P = 0.4).


Assuntos
Antineoplásicos/uso terapêutico , Asparaginase/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Trombose Venosa/tratamento farmacológico , Adolescente , Adulto , Antitrombinas/sangue , Veias Cerebrais/efeitos dos fármacos , Veias Cerebrais/patologia , Esquema de Medicação , Feminino , Fibrinolíticos/uso terapêutico , Heparina/uso terapêutico , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Trombose Venosa/etiologia , Trombose Venosa/mortalidade , Trombose Venosa/patologia
11.
J Biol Chem ; 288(20): 14624-14635, 2013 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-23558681

RESUMO

The microbial deconstruction of the plant cell wall is a key biological process that is of increasing importance with the development of a sustainable biofuel industry. The glycoside hydrolase families GH5 (PaMan5A) and GH26 (PaMan26A) endo-ß-1,4-mannanases from the coprophilic ascomycete Podospora anserina contribute to the enzymatic degradation of lignocellulosic biomass. In this study, P. anserina mannanases were further subjected to detailed comparative analysis of their substrate specificities, active site organization, and transglycosylation capacity. Although PaMan5A displays a classical mode of action, PaMan26A revealed an atypical hydrolysis pattern with the release of mannotetraose and mannose from mannopentaose resulting from a predominant binding mode involving the -4 subsite. The crystal structures of PaMan5A and PaMan26A were solved at 1.4 and 2.85 Å resolution, respectively. Analysis of the PaMan26A structure supported strong interaction with substrate at the -4 subsite mediated by two aromatic residues Trp-244 and Trp-245. The PaMan26A structure appended to its family 35 carbohydrate binding module revealed a short and proline-rich rigid linker that anchored together the catalytic and the binding modules.


Assuntos
Parede Celular/enzimologia , Glicosídeo Hidrolases/química , Oligossacarídeos/química , Podospora/enzimologia , Catálise , Domínio Catalítico , Glicosídeo Hidrolases/genética , Glicosilação , Hidrólise , Mutagênese , Polissacarídeos/química , Prolina/química , Estrutura Terciária de Proteína , Especificidade por Substrato
12.
Bull Cancer ; 111(2S): S29-S39, 2024 Feb.
Artigo em Francês | MEDLINE | ID: mdl-37045732

RESUMO

Relapse after allogeneic hematopoietic cell transplantation (allo-HCT) remains a major concern because it is associated with poor survival. A second allo-HCT is a valid option in this situation. During the 13th annual harmonization workshops of the francophone Society of bone marrow transplantation and cellular therapy (SFGM-TC), a designated working group reviewed the literature in order to update the second allo-HCT recommendations elaborated during the previous workshop (2016). The main indication for a second allo-HCT remains relapse of initial hematologic malignancy. Disease status; complete remission (CR), and relapse time after the first allo-HCT>6 months impact positively the overall survival of patients after the second allo-HCT. Donor change is a valid option, particularly if there is HLA loss on leukemic cells after a first haploidentical or following a mismatched allo-HCT is documented. Reduced intensity conditioning is recommended, while a sequential protocol is a reasonable option in patients with proliferative disease. A post-transplant maintenance strategy after hematological recovery is recommended as soon as day 60, even if the immunosuppressive treatment has not yet been stopped. Hypomethylating agents, and targeted therapies such as anti FLT3, anti BCL2, anti-IDH1/2, TKI, anti-TP53, anti-CD33, anti-CD19, anti-CD22, anti-CD30, check point inhibitors, and CAR-T cells can be used as a bridge to transplant or as an alternative treatment to the second allo-HCT.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Medula Óssea , Recidiva Local de Neoplasia , Neoplasias Hematológicas/terapia , Recidiva
13.
J Mycol Med ; 34(1): 101463, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342037

RESUMO

Hormographiella aspergillata is a basidiomycete exceptionally involved in invasive fungal infections (IFI). We report a case of H. aspergillata pulmonary infection in a 30-year-old female in a context of pancytopenia and relapsed of acute myeloid leukemia (AML). She presented with fever, thoracic pain, left pleural effusion and pneumonia, diagnosed on chest X-ray and CT-scan. Direct examination of a bronchoalveolar lavage (BAL) specimen performed on day (d) 10 was negative, while the culture was positive on d30. H. aspergillata was suspected, considering macroscopic and microscopic examination. Its identification was confirmed using Microflex® Bruker mass spectrometry and pan-fungal (PF)-PCR assay followed by DNA sequencing. After this initial diagnosis, the patient was monitored for 2.8 years. She was treated with liposomal amphotericin B and/or voriconazole until switching to isavuconazole on d298 due to side-effects. This antifungal treatment was maintained until d717 and then discontinued, the patient being considered as cured. Over this follow-up period, the patient was submitted to recurrent pulmonary sampling. Each time, cultures were negative, while PF - PCR assays and DNA sequencing confirmed the presence of H. aspergillata. The present case-report is the 32nd observation of H. aspergillata invasive infection showing that this IFI is still infrequent. Fifteen have occurred in patients with AML, which appears as the most frequent underlying disease favoring this IFI. Six recent case-reports in addition to ours highlight PF-PCR assays and DNA sequencing as relevant diagnostic tools that must be included in routine diagnosis and monitoring of IFI, specifically those due to rare basidiomycetes.


Assuntos
Agaricales , Basidiomycota , Leucemia Mieloide Aguda , Pneumopatias Fúngicas , Pneumonia , Adulto , Feminino , Humanos , Antifúngicos/uso terapêutico , Basidiomycota/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/microbiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
14.
Leuk Lymphoma ; 64(13): 2178-2187, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37615123

RESUMO

The combination of carmustine, etoposide, cytarabine, and melphalan (BEAM) followed by autologous stem cell transplantation (ASCT) is a commonly used intensification regimen for patients with Hodgkin lymphoma. As etoposide and cytarabine dosing are not defined, we conducted a retrospective, multicenter study, to compare efficacy and toxicity in 130 patients with Hodgkin lymphoma receiving etoposide and cytarabine at either 200 mg/m2/d (n = 50), 400 mg/m2/d (n = 35), or etoposide 200 mg/m2/d and cytarabine 400 mg/m2/d (n = 45). Progression-free survival and overall survival were not associated with the intensity of conditioning. Increased conditioning intensity was associated with longer duration of thrombocytopenia, a higher number of transfused RBC and platelet units and a higher frequency of mucositis, but serious adverse events or infectious complications were not increased. The intensity of BEAM regimen was not associated with survival but with the rate of cytopenia and mucositis advocating for the use of lower dosing in frail patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin , Mucosite , Humanos , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/terapia , Etoposídeo/efeitos adversos , Estudos Retrospectivos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Mucosite/induzido quimicamente , Transplante Autólogo , Citarabina/efeitos adversos , Carmustina/efeitos adversos , Melfalan/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
15.
EClinicalMedicine ; 62: 102111, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37654670

RESUMO

Background: Failure of gastrointestinal acute graft-versus-host disease (GI-aGvHD) to respond to steroid therapy is associated with limited further therapeutic options. We aimed to assess the safety and efficacy of the first-in-human use of the pooled allogeneic faecal microbiota, MaaT013, for the treatment of steroid-refractory GI-aGvHD. Methods: This prospective, international, single-arm, phase 2a study reports clinical outcomes from a 24-patient cohort with grade III-IV, steroid refractory GI-aGvHD treated with the pooled allogeneic faecal microbiota MaaT013. MaaT013 involved pooling faecal matter from 3 to 8 screened donors then transplanting the pooled batches into patients to treat GI-aGVHD. The 24 patients were treated in the HERACLES study (Aug 2018 to Nov 2020) at 26 sites in Europe and an additional 52 patients were treated in a compassionate use/expanded access program (EAP) in France (July 2018 to April 2021). The primary endpoint was GI response at day 28, defined as the proportion of patients with GI-aGvHD who had a complete response (CR) or very good partial response (VGPR). GvHD grading and staging were assessed according to the revised Glucksberg criteria. Adverse events and severe adverse events were monitored for 6 months and 12 months, respectively. The HERACLES study was registered with ClinicalTrials.gov (NCT03359980). Findings: Compared with single donors, MaaT013 is characterised by higher microbial richness and reduced variability across batches. At day 28 (D28), the GI-overall response rate (ORR) was 38% in the prospective population, including 5 complete responses (CR), 2 very good partial responses (VGPR) and 2 partial responses (PR). In the EAP, the GI-ORR was 58% (17 CR, 9 VGPR and 4 PR). The 12-month overall survival (OS) was 25% in the prospective study and 38% in the EAP. Regarding safety, five infectious complications, including 3 sepsis, could not be excluded from being related to the study procedure in HERACLES. Shotgun sequencing analyses of the identified strains suggest that none were found in MaaT013. In the EAP, 18 pharmacovigilance cases were reported among 52 treated patients, including 11 bacteraemia/sepsis. In HERACLES, we observed in stools from responding patients at D28 a higher microbiota richness and increased levels of beneficial bacteria, in particular butyrate producers, along with increased levels of short-chain fatty acid and bile acids. In contrast, stools from non-responding (NR) patients displayed increased levels of pathogenic pro-inflammatory bacteria along with increased systemic inflammatory parameters. Interpretation: Overall, MaaT013 was safe in this population of highly immunocompromised patients and was associated with responses in some patients with GI-aGvHD and deserves further investigation. Funding: MaaT Pharma.

16.
BMC Genomics ; 13: 57, 2012 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-22300648

RESUMO

BACKGROUND: Filamentous fungi are potent biomass degraders due to their ability to thrive in ligno(hemi)cellulose-rich environments. During the last decade, fungal genome sequencing initiatives have yielded abundant information on the genes that are putatively involved in lignocellulose degradation. At present, additional experimental studies are essential to provide insights into the fungal secreted enzymatic pools involved in lignocellulose degradation. RESULTS: In this study, we performed a wide analysis of 20 filamentous fungi for which genomic data are available to investigate their biomass-hydrolysis potential. A comparison of fungal genomes and secretomes using enzyme activity profiling revealed discrepancies in carbohydrate active enzymes (CAZymes) sets dedicated to plant cell wall. Investigation of the contribution made by each secretome to the saccharification of wheat straw demonstrated that most of them individually supplemented the industrial Trichoderma reesei CL847 enzymatic cocktail. Unexpectedly, the most striking effect was obtained with the phytopathogen Ustilago maydis that improved the release of total sugars by 57% and of glucose by 22%. Proteomic analyses of the best-performing secretomes indicated a specific enzymatic mechanism of U. maydis that is likely to involve oxido-reductases and hemicellulases. CONCLUSION: This study provides insight into the lignocellulose-degradation mechanisms by filamentous fungi and allows for the identification of a number of enzymes that are potentially useful to further improve the industrial lignocellulose bioconversion process.


Assuntos
Biomassa , Genoma Fúngico , Lignina/metabolismo , Ustilago/enzimologia , Análise por Conglomerados , Regulação Enzimológica da Expressão Gênica , Glicosídeo Hidrolases/metabolismo , Hidrólise , Oxirredutases/metabolismo , Proteoma/análise , Trichoderma/enzimologia , Ustilago/genética
17.
Appl Environ Microbiol ; 78(24): 8540-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23023747

RESUMO

Here we report the cloning of the Pa_3_10940 gene from the coprophilic fungus Podospora anserina, which encodes a C-terminal family 1 carbohydrate binding module (CBM1) linked to a domain of unknown function. The function of the gene was investigated by expression of the full-length protein and a truncated derivative without the CBM1 domain in the yeast Pichia pastoris. Using a library of polysaccharides of different origins, we demonstrated that the full-length enzyme displays activity toward a broad range of ß-glucan polysaccharides, including laminarin, curdlan, pachyman, lichenan, pustulan, and cellulosic derivatives. Analysis of the products released from polysaccharides revealed that this ß-glucanase is an exo-acting enzyme on ß-(1,3)- and ß-(1,6)-linked glucan substrates and an endo-acting enzyme on ß-(1,4)-linked glucan substrates. Hydrolysis of short ß-(1,3), ß-(1,4), and ß-(1,3)/ß-(1,4) gluco-oligosaccharides confirmed this striking feature and revealed that the enzyme performs in an exo-type mode on the nonreducing end of gluco-oligosaccharides. Excision of the CBM1 domain resulted in an inactive enzyme on all substrates tested. To our knowledge, this is the first report of an enzyme that displays bifunctional exo-ß-(1,3)/(1,6) and endo-ß-(1,4) activities toward beta-glucans and therefore cannot readily be assigned to existing Enzyme Commission groups. The amino acid sequence has high sequence identity to hypothetical proteins within the fungal taxa and thus defines a new family of glycoside hydrolases, the GH131 family.


Assuntos
Glucanos/metabolismo , Glicosídeo Hidrolases/metabolismo , Podospora/enzimologia , Clonagem Molecular , Expressão Gênica , Glicosídeo Hidrolases/classificação , Glicosídeo Hidrolases/genética , Pichia/genética , Podospora/genética , Especificidade por Substrato
18.
Appl Environ Microbiol ; 78(18): 6483-90, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22773628

RESUMO

In this study, natural fungal diversity in wood-decaying species was explored for biomass deconstruction. In 2007 and 2008, fungal isolates were collected in temperate forests mainly from metropolitan France and in tropical forests mainly from French Guiana. We recovered and identified 74 monomorph cultures using morphological and molecular identification tools. Following production of fungal secretomes under inductive conditions, we evaluated the capacity of these fungal strains to potentiate a commercial Trichoderma reesei cellulase cocktail for the release of soluble sugars from biomass. The secretome of 19 isolates led to an improvement in biomass conversion of at least 23%. Of the isolates, the Trametes gibbosa BRFM 952 (Banque de Ressources Fongiques de Marseille) secretome performed best, with 60% improved conversion, a feature that was not universal to the Trametes and related genera. Enzymatic characterization of the T. gibbosa BRFM 952 secretome revealed an unexpected high activity on crystalline cellulose, higher than that of the T. reesei cellulase cocktail. This report highlights the interest in a systematic high-throughput assessment of collected fungal biodiversity to improve the enzymatic conversion of lignocellulosic biomass. It enabled the unbiased identification of new fungal strains issued from biodiversity with high biotechnological potential.


Assuntos
Biodiversidade , Biomassa , Celulases/isolamento & purificação , Fungos/classificação , Fungos/enzimologia , Árvores/microbiologia , Madeira/metabolismo , Celulases/genética , Celulases/metabolismo , DNA Fúngico/química , DNA Fúngico/genética , França , Guiana Francesa , Fungos/genética , Fungos/isolamento & purificação , Glucose/metabolismo , Dados de Sequência Molecular , Análise de Sequência de DNA , Clima Tropical
19.
PLoS One ; 17(4): e0267509, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35452491

RESUMO

ß-Mannans are a heterogeneous group of polysaccharides with a common main chain of ß-1,4-linked mannopyranoside residues. The cleavage of ß-mannan chains is catalyzed by glycoside hydrolases called ß-mannanases. In the CAZy database, ß-mannanases are grouped by sequence similarity in families GH5, GH26, GH113 and GH134. Family GH113 has been under-explored so far with six enzymes characterized, all from the Firmicutes phylum. We undertook the functional characterization of 14 enzymes from a selection of 31 covering the diversity of the family GH113. Our observations suggest that GH113 is a family with specificity towards mannans, with variations in the product profiles and modes of action. We were able to assign mannanase and mannosidase activities to four out of the five clades of the family, increasing by 200% the number of characterized GH113 members, and expanding the toolbox for fine-tuning of mannooligosaccharides.


Assuntos
Firmicutes , Glicosídeo Hidrolases , Mananas , Firmicutes/enzimologia , Firmicutes/genética , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Mananas/química , Manose , Especificidade por Substrato , beta-Manosidase/metabolismo
20.
Leukemia ; 36(10): 2408-2417, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35962057

RESUMO

Several scoring systems have been developed to assess suitability of individual patients for intensive acute myeloid leukemia (AML) therapy. We sought to compare the performance of these scores in a cohort of 428 consecutive adults with AML who received conventional induction chemotherapy in five academic centers in France. All scoring systems identified a subset of patients with increased 28 and 56-day mortality although the prediction accuracy was overall limited with C-statistics of ranging from 0.61 to 0.71 Overall survival (OS) prediction was more limited and restricted to scoring systems that include AML-related parameters. The outcome of 104 patients (24%) considered unsuitable for intensive chemotherapy based on criteria used in recent randomized trials was similar to that of the other 324 patients (28-day mortality, odds ratio [OR] = 1.88, P = 0.2; 56-day mortality, OR = 1.71, P = 0.21; event-free survival, hazard ratio [HR] = 1.08, P = 0.6; OS, HR = 1.25, P = 0.14) with low discrimination (C-statistic: 0.57, 0.56, 0.50, and 0.52 for 28-day, 56-day mortality, EFS, and OS, respectively). Together, our findings indicate that the accuracy of currently available approaches to identify patients at increased risk of early mortality and shortened survival after intensive AML therapy is relatively limited. Caution regarding the use of available scoring systems should be warranted in clinical decision-making.


Assuntos
Objetivos , Leucemia Mieloide Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Quimioterapia de Indução , Modelos de Riscos Proporcionais
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