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1.
J Appl Physiol (1985) ; 136(4): 764-773, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38328824

RESUMO

Estradiol and estrogen receptor α (ERα) have been shown to be important for the maintenance of skeletal muscle strength in females; however, little is known about the roles of estradiol and ERα in male muscle. The purpose of this study was to determine if skeletal muscle ERα is required for optimal contractility in male mice. We hypothesize that reduced ERα in skeletal muscle impairs contractility in male mice. Skeletal muscle-specific knockout (skmERαKO) male mice exhibited reduced strength across multiple muscles and several contractile parameters related to force generation and kinetics compared with wild-type littermates (skmERαWT). Isolated EDL muscle-specific isometric tetanic force, peak twitch force, peak concentric and peak eccentric forces, as well as the maximal rates of force development and relaxation were 11%-21% lower in skmERαKO compared with skmERαWT mice. In contrast, isolated soleus muscles from skmERαKO mice were not affected. In vivo peak torque of the anterior crural muscles was 20% lower in skmERαKO compared with skmERαWT mice. Muscle masses, contractile protein contents, fiber types, phosphorylation of the myosin regulatory light chain, and caffeine-elicited force did not differ between muscles of skmERαKO and skmERαWT mice, suggesting that strength deficits were not due to size, composition, or calcium release components of muscle contraction. These results indicate that in male mice, reduced skeletal muscle ERα blunts contractility to a magnitude similar to that previously reported in females; however, the mechanism may be sexually dimorphic.NEW & NOTEWORTHY We comprehensively measured in vitro and in vivo contractility of leg muscles with reduced estrogen receptor α (ERα) in male mice and reported that force generation and contraction kinetics are impaired. In contrast to findings in females, phosphorylation of myosin regulatory light chain cannot account for low force production in male skeletal muscle ERα knockout mice. These results indicate that ERα is required for optimal contractility in males and females but via sexually dimorphic means.


Assuntos
Receptor alfa de Estrogênio , Cadeias Leves de Miosina , Feminino , Masculino , Animais , Camundongos , Receptor alfa de Estrogênio/metabolismo , Cadeias Leves de Miosina/metabolismo , Músculo Esquelético/fisiologia , Contração Muscular/fisiologia , Estradiol/metabolismo , Camundongos Endogâmicos C57BL
4.
Hematol Oncol Clin North Am ; 37(4): 787-799, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37246087

RESUMO

Histologic transformation (HT) to diffuse large B-cell lymphoma occurs rarely in Waldenström macroglobulinemia, with higher incidence in MYD88 wild-type patients. HT is suspected clinically when rapidly enlarging lymph nodes, elevated lactate dehydrogenase levels, or extranodal disease occur. Histologic assessment is required for diagnosis. HT carries a worse prognosis compared with nontransformed Waldenström macroglobulinemia. A validated prognostic score based on three adverse risk factors stratifies three risk groups. The most common frontline treatment is chemoimmunotherapy, such as R-CHOP. Central nervous system prophylaxis should be considered if feasible and consolidation with autologous transplant should be discussed in fit patients responding to chemoimmunotherapy.


Assuntos
Linfoma Difuso de Grandes Células B , Macroglobulinemia de Waldenstrom , Humanos , Macroglobulinemia de Waldenstrom/patologia , Ciclofosfamida , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/terapia , Linfoma Difuso de Grandes Células B/patologia , Prognóstico , Rituximab , Fator 88 de Diferenciação Mieloide/genética , Mutação
5.
Hemasphere ; 7(2): e833, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36713354

RESUMO

Post-transplant lymphoproliferative disorder (PTLD) is a rare complication of immunosuppression. Sequential treatment is commonly proposed, combining induction with rituximab (R-induction) followed by either continuation of treatment or addition of chemotherapy depending on response. Response to R-induction, often assessed by CT scan, is a major predictor of overall survival (OS). The aim of the study was to analyze predictive factors of R-induction response, including total metabolic tumor volume (TMTV), and investigate the role of 18F-FDG PET/CT in response assessment. This retrospective multicenter study is based on patients with PTLD included in the K-VIROGREF cohort. Only patients treated by R-induction with a baseline 18F-FDG PET/CT were included. Response to R-induction was assessed by 18F-FDG PET/CT. The optimal threshold of TMTV for rituximab response was determined using receiver operating characteristic curves. Univariate and multivariate analyses were conducted to identify predictive factors of response. A total of 67 patients were included. Survival characteristics were similar to those previously reported: the complete response rate to R-induction was 30%, the 3-year OS estimate was 66%, and the treatment-related mortality was 4%. The optimal threshold for TMTV to predict R-induction response was 135 cm3. The response rate to R-induction was 38% in the 21 patients with TMTV ≥ 135 cm3 and 72% in the 46 patients with TMTV < 135 cm3. TMTV was a significant predictor of response, both at univariate and multivariate analyses (odd ratios = 3.71, P = 0.022). Baseline TMTV is predictive of response to R-induction. Early assessment of patient response is feasible with 18F-FDG PET/CT.

6.
Hematol Oncol ; 40(3): 400-408, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35385885

RESUMO

In symptomatic Waldenström macroglobulinemia (sWM) patients, prognosis is assessed with the international prognostic scoring system (IPSSWM). In follicular lymphoma and other B-cell and T-cell lymphomas, disease progression within 24 months (POD24) or (in patients without POD24) after 24 months has been proposed as the start date for stratifying subsequent survival. In the present report, we assessed in a large series of 472 sWM patients, the prognostic value of this new dynamic endpoint already reported in many other lymphomas subtypes. The 3 year subsequent survival for patients with POD24 was 75% and 93% for patients without POD24. In sWM patients, departure from the proportional hazards assumption complicated this analysis. In patients without POD24, the median subsequent progression-free survival time of 43 months accounted for favorable outcome, whereas survival after progression was not influenced by the time to progression. In addition, sensitivity analysis showed that the baseline IPSSWM score also influenced survival after POD24. In sWM patients, we conclude that the apparent difference in survival after POD24 or the 24 months time-point (in patients without POD24) is mainly explained by the prolonged subsequent progression free survival of latter patients. Indeed, the mortality after progression is not influenced by the time to this event.


Assuntos
Progressão da Doença , Macroglobulinemia de Waldenstrom , Humanos , Prognóstico , Intervalo Livre de Progressão , Macroglobulinemia de Waldenstrom/patologia , Macroglobulinemia de Waldenstrom/terapia
8.
Sci Total Environ ; 767: 144994, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550059

RESUMO

Ecosystem functions are driven by abiotic and biotic factors, but due to high collinearity of both, it is often difficult to disentangle the drivers of these ecosystem functions. We studied sedimentological and faunal controls of benthic organic matter mineralization, a crucial ecosystem process provided for by sediments of shelf seas. Subtidal benthic habitats representative of the wide permeability gradient found in the Belgian Part of the North Sea (Northeast Atlantic Shelf) were characterized in terms of sediment descriptors, macrofauna, and sediment biogeochemistry was estimated. Our results confirmed a strong correlation between sediment characteristics and macrofauna, and estimated sediment biogeochemical process rates were clearly linked to both. Results of variance partitioning and statistical modelling showed that oxic mineralization and nitrification were mainly regulated by faunal activities whereas anoxic mineralization was regulated by sediment properties, with permeability as a decisive factor. Both biotic and abiotic factors were needed to explain variability in oxygen consumption and total mineralization estimates, suggesting that macrofaunal activities have different effects across habitats. The statistical models were a useful tool to interpret the impact of anthropogenic activities in the study area and represent a step towards predicting the effects of human activities on crucial ecosystem functions.


Assuntos
Carbono , Ecossistema , Carbono/análise , Sedimentos Geológicos , Humanos , Nitrogênio , Mar do Norte , Oceanos e Mares , Permeabilidade
9.
Haematologica ; 106(11): 2940-2946, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33179472

RESUMO

Histological transformation into diffuse large B-cell lymphoma is a rare complication in patients with Waldenström macroglobulinemia (WM) usually associated with a poor prognosis. The objective of this study was to develop and validate a prognostic index for survival in transformed WM patients. Through this multicenter, international collaborative effort, we developed a scoring system based on data from 133 patients with transformed WM who were evaluated between 1995 and 2016 (training cohort). Univariate and multivariate analyses were used to propose a prognostic index with 2-year survival after transformation as an end-point. For external validation, a data set of 67 patients was used to evaluate the performance of the model (validation cohort). By multivariate analysis, three adverse covariates were identified as independent predictors of 2-year survival after transformation: elevated serum LDH (2 points), platelet count < 100 x 109/L (1 point) and any previous treatment for WM (1 point). Three risk groups were defined: low-risk (0-1 point, 24% of patients), intermediate-risk (2-3 points, 59%, hazard ratio (HR) = 3.4) and high-risk (4 points, 17%, HR = 7.5). Two-year survival rates were 81%, 47%, and 21%, respectively (P < 0.0001). This model appeared to be a better discriminant than the International Prognostic Index (IPI) and the revised IPI (R-IPI). We validated this model in an independent cohort. This easy-to-compute scoring index is a robust tool that may allow identification of groups of transformed WM patients with different outcomes and could be used for improving the development of risk-adapted treatment strategies.


Assuntos
Linfoma Difuso de Grandes Células B , Macroglobulinemia de Waldenstrom , Humanos , Prognóstico , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Macroglobulinemia de Waldenstrom/diagnóstico
11.
Int J Infect Dis ; 80: 134-136, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639623

RESUMO

Ruxolitinib is a JAK-1/JAK-2 inhibitor indicated for the treatment of polycythemia vera and primary or secondary myelofibrosis. Only one patient (0.2%) was diagnosed with tuberculosis among the 485 patients receiving ruxolitinib in the four pivotal trials. Fourteen cases of tuberculosis have since been reported. We observed two (3%) mycobacterial infections (one due to Mycobacterium tuberculosis and one due to Mycobacterium avium complex) in our cohort of 65 patients receiving ruxolitinib. This observation suggests that the rate of mycobacterial infection might be higher than that observed in the pivotal trials and that atypical mycobacterial infections can also occur.


Assuntos
Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Mielofibrose Primária/tratamento farmacológico , Pirazóis/uso terapêutico , Tuberculose/tratamento farmacológico , Idoso , Feminino , Humanos , Masculino , Mycobacterium avium/efeitos dos fármacos , Mycobacterium avium/isolamento & purificação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Nitrilas , Policitemia Vera/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas
12.
Sci Rep ; 9(1): 701, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679590

RESUMO

A chronic antigenic stimulation is believed to sustain the leukemogenic development of chronic lymphocytic leukemia (CLL) and most of lymphoproliferative malignancies developed from mature B cells. Reproducing a proliferative stimulation ex vivo is critical to decipher the mechanisms of leukemogenesis in these malignancies. However, functional studies of CLL cells remains limited since current ex vivo B cell receptor (BCR) stimulation protocols are not sufficient to induce the proliferation of these cells, pointing out the need of mandatory BCR co-factors in this process. Here, we investigated benefits of several BCR co-stimulatory molecules (IL-2, IL-4, IL-15, IL-21 and CD40 ligand) in multiple culture conditions. Our results demonstrated that BCR engagement (anti-IgM ligation) concomitant to CD40 ligand, IL-4 and IL-21 stimulation allowed CLL cells proliferation ex vivo. In addition, we established a proliferative advantage for ZAP70 positive CLL cells, associated to an increased phosphorylation of ZAP70/SYK and STAT6. Moreover, the use of a tri-dimensional matrix of methylcellulose and the addition of TLR9 agonists further increased this proliferative response. This ex vivo model of BCR stimulation with T-derived cytokines is a relevant and efficient model for functional studies of CLL as well as lymphoproliferative malignancies.


Assuntos
Linfócitos B/patologia , Proliferação de Células , Leucemia Linfocítica Crônica de Células B/patologia , Receptores de Antígenos de Linfócitos B/metabolismo , Fator de Transcrição STAT6/metabolismo , Quinase Syk/metabolismo , Proteína-Tirosina Quinase ZAP-70/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Linfócitos B/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Fosforilação , Células Tumorais Cultivadas
13.
J Mol Diagn ; 20(3): 298-306, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29471112

RESUMO

Invasive pulmonary aspergillosis (IPA) is a common complication of immunosuppression. Rapid diagnosis using molecular techniques is essential to improve patient survival. PCR techniques are promising in enhancing Aspergillus detection in blood and respiratory samples. We evaluate for the first time the performances of two commercial real-time PCR kits, the A. fumigatus Bio-Evolution and the MycoGENIE A. fumigatus for the detection of A. fumigatus DNA in bronchoalveolar lavage (BAL) from patients with and without IPA. Seventy-three BAL samples were included. Thirty-one of them corresponded to patients with probable IPA, 11 to patients with possible IPA, and 31 to patients without aspergillosis, according to the 2008 European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria. In the probable IPA group, A. fumigatus Bio-Evolution and the MycoGENIE A. fumigatus real-time PCR kits showed a specificity of 100% and a sensitivity of 81% and 71%, respectively. The A. fumigatus Bio-Evolution detected Aspergillus DNA in the 14 BAL samples with a positive Aspergillus culture result, whereas the MycoGENIE A. fumigatus PCR result was positive only for 12. In the possible IPA group, there were no positive real-time PCR or positive Aspergillus culture results. For the patients without aspergillosis, no positive result was observed for real-time PCR kit, despite the presence of various other non-Aspergillus pathogens in this group. Our study demonstrates an excellent specificity and a good sensitivity of A. fumigatus DNA detection in BAL samples with both kits.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , DNA Fúngico/isolamento & purificação , Aspergilose Pulmonar Invasiva/microbiologia , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Fúngico/genética , Feminino , Galactose/análogos & derivados , Humanos , Masculino , Mananas/metabolismo , Pessoa de Meia-Idade
14.
Br J Haematol ; 179(3): 439-448, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28770576

RESUMO

Histological transformation (HT) to diffuse large B-cell lymphoma (DLBCL) is a rare and poorly reported complication of Waldenström macroglobulinaemia (WM). We performed a retrospective study of 77 WM patients with biopsy-proven transformation to DLBCL. The median time from WM diagnosis to HT was 4·6 years and 16 patients (21%) had never been treated for WM. At HT, extranodal sites were observed in 91% of patients with a rather high incidence of central nervous system, cutaneous or testicular involvement. Fluorodeoxyglucose-positron emission tomography was performed in half of the patients and the median maximum standardized uptake value was 15 for transformed disease. More than 80% of cases with available data for assessment by the Hans' algorithm harboured a non-germinal centre B-cell phenotype. First-line treatment for transformation consisted of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone)-like regimen in 85% of patients. The overall response rate after first-line treatment was 61% and the median overall survival was only 16 months for the entire cohort. Time to transformation above 5 years (P = 0·0004) and elevated LDH (P = 0·02) were associated with worse outcome. Based on these findings, HT should be considered and lead to a biopsy in WM patients presenting with extranodal involvement, elevated LDH and constitutional symptoms. The optimal therapeutic approaches remain to be defined.


Assuntos
Transformação Celular Neoplásica/patologia , Linfoma Difuso de Grandes Células B/patologia , Macroglobulinemia de Waldenstrom/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Biópsia , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Fluordesoxiglucose F18 , Humanos , L-Lactato Desidrogenase/sangue , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Prednisona/uso terapêutico , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Rituximab , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vincristina/uso terapêutico , Macroglobulinemia de Waldenstrom/diagnóstico por imagem
15.
J Antimicrob Chemother ; 72(suppl_1): i48-i58, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28355467

RESUMO

Recently, several randomized studies have been published that will shape treatment decisions in the prevention and management of invasive mould infections. Liposomal amphotericin B is an option for empirical or targeted treatment of invasive aspergillosis or mucormycosis, but for prophylaxis therapy, the triazole class now predominates. The triazole voriconazole is currently regarded as a drug of choice for the treatment of proven or probable invasive aspergillosis, and has shown significantly higher response rates than amphotericin B deoxycholate in this setting, with fewer severe drug-related adverse events. Isavuconazole, the newest triazole agent, offers the advantages of once-daily dosing, a wider spectrum of antifungal activity than voriconazole, predictable pharmacokinetics and fewer CYP enzyme-mediated drug interactions. A recent large randomized clinical trial showed mortality to be similar under isavuconazole or voriconazole in patients with invasive mould disease, with fewer drug-related adverse events in isavuconazole-treated patients. Another study has indicated that isavuconazole is also effective in mucormycosis infections but patient numbers were small and confirmation is awaited. Experimental studies combining different drug classes with antimould activity have been promising, but the clinical database is limited. A large randomized trial of combination therapy compared voriconazole plus the echinocandin anidulafungin versus voriconazole monotherapy in patients with invasive aspergillosis. Results showed the overall response rate to be similar, but combination therapy improved survival for the subpopulation of patients in whom the diagnosis was confirmed by serum and/or bronchoalveolar lavage fluid galactomannan positivity. This active field of research is likely to continue evolving rapidly in the coming years.


Assuntos
Antibioticoprofilaxia/métodos , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Infecções Fúngicas Invasivas/tratamento farmacológico , Mucormicose/tratamento farmacológico , Anfotericina B/uso terapêutico , Anidulafungina , Aspergilose/prevenção & controle , Quimioterapia Combinada , Equinocandinas/uso terapêutico , Humanos , Mucormicose/prevenção & controle , Nitrilas/uso terapêutico , Piridinas/uso terapêutico , Triazóis/uso terapêutico , Voriconazol/uso terapêutico
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