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1.
Aging Cell ; : e14289, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102875

RESUMO

Neuronal senescence is a major risk factor for the development of many neurodegenerative disorders. The mechanisms that drive neurons to senescence remain largely elusive; however, dysregulated mitochondrial physiology seems to play a pivotal role in this process. Consequently, strategies aimed to preserve mitochondrial function may hold promise in mitigating neuronal senescence. For example, dietary restriction has shown to reduce senescence, via a mechanism that still remains far from being totally understood, but that could be at least partially mediated by mitochondria. Here, we address the role of mitochondrial inorganic polyphosphate (polyP) in the intersection between neuronal senescence and dietary restriction. PolyP is highly present in mammalian mitochondria; and its regulatory role in mammalian bioenergetics has already been described by us and others. Our data demonstrate that depletion of mitochondrial polyP exacerbates neuronal senescence, independently of whether dietary restriction is present. However, dietary restriction in polyP-depleted cells activates AMPK, and it restores some components of mitochondrial physiology, even if this is not sufficient to revert increased senescence. The effects of dietary restriction on polyP levels and AMPK activation are conserved in differentiated SH-SY5Y cells and brain tissue of male mice. Our results identify polyP as an important component in mitochondrial physiology at the intersection of dietary restriction and senescence, and they highlight the importance of the organelle in this intersection.

2.
Front Cell Dev Biol ; 12: 1423208, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39050895

RESUMO

The existing literature points towards the presence of robust mitochondrial mechanisms aimed at mitigating protein dyshomeostasis within the organelle. However, the precise molecular composition of these mechanisms remains unclear. Our data show that inorganic polyphosphate (polyP), a polymer well-conserved throughout evolution, is a component of these mechanisms. In mammals, mitochondria exhibit a significant abundance of polyP, and both our research and that of others have already highlighted its potent regulatory effect on bioenergetics. Given the intimate connection between energy metabolism and protein homeostasis, the involvement of polyP in proteostasis has also been demonstrated in several organisms. For example, polyP is a bacterial primordial chaperone, and its role in amyloidogenesis has already been established. Here, using mammalian models, our study reveals that the depletion of mitochondrial polyP leads to increased protein aggregation within the organelle, following stress exposure. Furthermore, mitochondrial polyP is able to bind to proteins, and these proteins differ under control and stress conditions. The depletion of mitochondrial polyP significantly affects the proteome under both control and stress conditions, while also exerting regulatory control over gene expression. Our findings suggest that mitochondrial polyP is a previously unrecognized, and potent component of mitochondrial proteostasis.

3.
Cancers (Basel) ; 16(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38672542

RESUMO

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) especially affects the older population. Old (≥60 years) and very old age (≥80 years) DLBCL patients often present high-risk molecular alterations, lower tolerability to conventional immunochemotherapy, and poor clinical outcomes. In this scenario, attenuated therapeutic strategies, such as the R-MiniCHOP and R-MiniCHOP of the elderly regimens, have emerged for this particularly fragile population. However, the responses, clinical outcomes, and toxicities of these regimens currently remain poorly understood, mainly because these individuals are not usually included in controlled clinical trials. METHODS: This retrospective, observational, and single-center real-world study included 185 DLBCL, NOS patients older than 70 years treated at the largest oncology center in Latin America from 2009 to 2020. We aimed to assess the outcomes, determine survival predictors, and compare responses and toxicities between three different primary therapeutic strategies, including the conventional R-CHOP regimen and the attenuated R-MiniCHOP and R-MiniCHOP of the elderly protocols. RESULTS: The median age at diagnosis was 75 years (70-97 years), and 58.9% were female. Comorbidities were prevalent, including 19.5% with immobility, 28.1% with malnutrition, and 24.8% with polypharmacy. Advanced clinical stage was observed in 72.4%, 48.6% had bulky disease ≥7 cm, 63.2% had B-symptoms, and 67.0% presented intermediate-high/high-risk IPI. With a median follow-up of 6.3 years, the estimated 5-year OS and PFS were 50.2% and 44.6%, respectively. The R-MiniCHOP of the elderly regimen had a lower ORR (p = 0.040); however, patients in this group had higher rates of unfavorable clinical and laboratory findings, including hypoalbuminemia (p = 0.001), IPI ≥ 3 (p = 0.013), and NCCN-IPI ≥ 3 (p = 0.002). Although associated with higher rates of severe neutropenia (p = 0.003), the R-CHOP regimen promoted increased OS (p = 0.003) and PFS (p = 0.005) in comparison to the attenuated protocols. Additionally, age ≥ 75 years, high levels of LDH, B-symptoms, advanced clinical stage (III/IV), neutrophilia, and low lymphocyte/monocyte ratio were identified as poor prognostic factors in this cohort. CONCLUSIONS: In this large and real-life Latin American cohort, we demonstrated that patients with DLBCL, NOS older than 70 years still do not have satisfactory clinical outcomes in 2024, with half of cases not reaching 5 years of life expectancy after diagnosis. Although the conventional R-CHOP offers response and survival advantages over attenuated regimens, its myelotoxicity is not negligible. Therefore, the outcomes reported and the prognostic factors here identified may assist clinicians in the appropriate selection of therapeutic strategies adapted to the risk for old and very old DLBCL patients.

4.
Estima (Online) ; 21(1): e1321, jan-dez. 2023.
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem | ID: biblio-1510763

RESUMO

Objetivos:identificar as orientações fornecidas aos pacientes com úlceras venosas (UVs) submetidos à telenfermagem e descrever o desfecho ocorrido com os pacientes com UVs monitorados à distância. Método: estudo transversal e documental, realizado com 159 prontuários de pacientes com UV submetidos à telenfermagem numa clínica de estomaterapia no Rio de Janeiro. Os critérios de inclusão foram pacientes com diagnóstico de UV submetidos à telenfermagem, de abril de 2018 a fevereiro de 2020. A análise de dados ocorreu por meio de estatística descritiva (frequência absoluta e relativa para as variáveis categóricas), auxiliada por planilha do aplicativo Microsoft Excel. Resultados: identificou-se um equilíbrio entre os participantes em relação ao sexo; apresentaram idade média (desvio-padrão) de 68,07 (5,28); ensino fundamental completo ou médio incompleto; aposentados ou pensionistas. Verificou-se que 40,88% dos pacientes possuíam ao menos uma doença de base, predominando hipertensão arterial sistêmica e diabetes mellitus. As orientações mais prevalentes foram: repouso com os membros inferiores elevados, utilização da terapia compressiva com meia elástica ou atadura elástica e realização da troca de curativo secundário em sua residência. Conclusão: os achados evidenciam a necessidade de ampliar as ações de enfermagem desenvolvidas na Clínica, buscando proporcionar a saúde integral aos pacientes.


Objectives:To identify the guidelines provided to patients with venous ulcers submitted to telenursing and describe the outcome that occurred with patients with venous ulcers monitored remotely. Method: Cross-sectional and documentary study, carried out with 159 medical records of patients with venous ulcers submitted to telenursing at an enterostomal therapy clinic in Rio de Janeiro, Brazil. The inclusion criteria were patients with a diagnosis of venous ulcer submitted to Telenursing, from April 2018 to February 2020. Data analysis was performed using descriptive statistics (absolute and relative frequency for categorical variables), aided by the application spreadsheet Microsoft Excel. Results: A balance was identified between the participants in relation to gender; had a mean age (standard deviation) of 68.07 (5.28); completed elementary school or incomplete high school; retirees or pensioners. It was found that 40.88% of the patients had at least one underlying disease, predominantly systemic arterial hypertension and diabetes mellitus. The most prevalent guidelines were: resting with the lower limbs elevated, using compressive therapy with elastic stockings or elastic bandage, and changing the secondary dressing at home. Conclusion: The findings show the need to expand the nursing actions developed at the clinic, seeking to provide comprehensive health to patients.


Objetivos:identificar las orientaciones proporcionadas a los pacientes con úlceras venosas sometidos a Teleenfermería y describir el desenlace ocurrido con los pacientes con úlceras venosas monitorizados a distancia. Método: estudio transversal y documental, realizado con 159 prontuarios de pacientes con úlceras venosas sometidos a teleenfermería en una Clínica de Estomaterapia de Rio de Janeiro. Los criterios de inclusión fueron pacientes con diagnóstico de úlcera venosa sometidos a teleenfermería, de abril de 2018 a febrero de 2020. El análisis de datos se realizó mediante estadística descriptiva (frecuencia absoluta y relativa para variables categóricas), auxiliada por la hoja de cálculo de la aplicación Microsoft Excel. Resultados: se identificó un equilibrio entre los participantes en relación al género; tenía una edad media (DE) de 68,07 (5,28); primaria completa o secundaria incompleta; jubilados o pensionados. Se encontró que el 40,88% de los pacientes tenían al menos una enfermedad de base, predominantemente Hipertensión Arterial Sistémica y Diabetes Mellitus. Las pautas más prevalentes fueron: reposo con los miembros inferiores elevados, uso de terapia compresiva con medias elásticas o venda elástica y cambio del vendaje secundario en casa. Conclusión: los hallazgos muestran la necesidad de ampliar las acciones de enfermería desarrolladas en la Clínica, buscando brindar salud integral a los pacientes


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Úlcera Varicosa/enfermagem , Telemonitoramento , Estomaterapia , Estudos Transversais , Assistência Integral à Saúde , Fatores Sociodemográficos
5.
Biochem Soc Trans ; 51(6): 2153-2161, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-37955101

RESUMO

Inorganic polyphosphate (polyP) is an ancient polymer that is well-conserved throughout evolution. It is formed by multiple subunits of orthophosphates linked together by phosphoanhydride bonds. The presence of these bonds, which are structurally similar to those found in ATP, and the high abundance of polyP in mammalian mitochondria, suggest that polyP could be involved in the regulation of the physiology of the organelle, especially in the energy metabolism. In fact, the scientific literature shows an unequivocal role for polyP not only in directly regulating oxidative a phosphorylation; but also in the regulation of reactive oxygen species metabolism, mitochondrial free calcium homeostasis, and the formation and opening of mitochondrial permeability transitions pore. All these processes are closely interconnected with the status of mitochondrial bioenergetics and therefore play a crucial role in maintaining mitochondrial and cell physiology. In this invited review, we discuss the main scientific literature regarding the regulatory role of polyP in mammalian mitochondrial physiology, placing a particular emphasis on its impact on energy metabolism. Although the effects of polyP on the physiology of the organelle are evident; numerous aspects, particularly within mammalian cells, remain unclear and require further investigation. These aspects encompass, for example, advancing the development of more precise analytical methods, unraveling the mechanism responsible for sensing polyP levels, and understanding the exact molecular mechanism that underlies the effects of polyP on mitochondrial physiology. By increasing our understanding of the biology of this ancient and understudied polymer, we could unravel new pharmacological targets in diseases where mitochondrial dysfunction, including energy metabolism dysregulation, has been broadly described.


Assuntos
Mitocôndrias , Polifosfatos , Animais , Metabolismo Energético , Mamíferos/metabolismo , Mitocôndrias/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Polímeros , Polifosfatos/metabolismo
6.
Cancers (Basel) ; 15(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37835453

RESUMO

BACKGROUND: Mantle cell lymphoma (MCL) is a rare malignancy with heterogeneous behavior. Despite the therapeutic advances recently achieved, MCL remains incurable. Currently, the standard of care for young and fit patients involves induction immunochemotherapy followed by up-front autologous stem cell transplantation (ASCT). However, the role of more intensive induction regimens, such as those based on high doses of cytarabine (HDAC), remains controversial in the management of ASCT-eligible patients. METHODS: This retrospective, observational, and single-center study involved 165 MCL patients treated at the largest oncology center in Latin America from 2010 to 2022. We aimed to assess outcomes, determine survival predictors, and compare responses between different primary therapeutic strategies, with a focus on assessing the impact of HDAC-based regimens on outcomes in ASCT-eligible patients. RESULTS: The median age at diagnosis was 65 years (38-89 years), and 73.9% were male. More than 90% of the cases had a classic nodal form (cnMCL), 76.4% had BM infiltration, and 56.4% presented splenomegaly. Bulky ≥ 7 cm, B-symptoms, ECOG ≥ 2, and advanced-stage III/IV were observed in 32.7%, 64.8%, 32.1%, and 95.8%, respectively. Sixty-four percent of patients were categorized as having high-risk MIPI. With a median follow-up of 71.1 months, the estimated 2-year OS and EFS were 64.1% and 31.8%, respectively. Patients treated with (R)-HDAC-based regimens had a higher ORR (85.9% vs. 65.7%, p = 0.007) compared to those receiving (R)-CHOP, as well as lower POD-24 rates (61.9% vs. 80.4%, p = 0.043) and lower mortality (43.9% vs. 68.6%, p = 0.004). However, intensified induction regimens with (R)-HDAC were not associated with a real OS benefit in MCL patients undergoing up-front consolidation with ASCT (2-year OS: 88.7% vs. 78.8%, p = 0.289). Up-front ASCT was independently associated with increased OS (p < 0.001), EFS (p = 0.005), and lower POD-24 rates (p < 0.001) in MCL. Additionally, CNS infiltration, TLS, hypoalbuminemia, and the absence of remission after induction were predictors of poor OS. CONCLUSIONS: In the largest Latin American cohort of MCL patients, we confirmed the OS benefit promoted by up-front consolidation with ASCT in young and fit patients, regardless of the intensity of the immunochemotherapy regimen used in the pre-ASCT induction. Although HDAC-based regimens were not associated with an unequivocal increase in OS for ASCT-eligible patients, it was associated with higher ORR and lower rates of early relapses for the whole cohort.

7.
Int J Mol Sci ; 24(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37762163

RESUMO

Inorganic polyphosphate (polyP) is an evolutionarily conserved and ubiquitous polymer that is present in all studied organisms. PolyP consists of orthophosphates (Pi) linked together by phosphoanhydride bonds. The metabolism of polyP still remains poorly understood in higher eukaryotes. Currently, only F0F1-ATP synthase, Nudt3, and Prune have been proposed to be involved in this metabolism, although their exact roles and regulation in the context of polyP biology have not been fully elucidated. In the case of Prune, in vitro studies have shown that it exhibits exopolyphosphatase activity on very short-chain polyP (up to four units of Pi), in addition to its known cAMP phosphodiesterase (PDE) activity. Here, we expand upon studies regarding the effects of human Prune (h-Prune) on polyP metabolism. Our data show that recombinant h-Prune is unable to hydrolyze short (13-33 Pi) and medium (45-160 Pi) chains of polyP, which are the most common chain lengths of the polymer in mammalian cells. Moreover, we found that the knockdown of h-Prune (h-Prune KD) results in significantly decreased levels of polyP in HEK293 cells. Likewise, a reduction in the levels of polyP is also observed in Drosophila melanogaster loss-of-function mutants of the h-Prune ortholog. Furthermore, while the activity of ATP synthase, and the levels of ATP, are decreased in h-Prune KD HEK293 cells, the expression of ATP5A, which is a main component of the catalytic subunit of ATP synthase, is upregulated in the same cells, likely as a compensatory mechanism. Our results also show that the effects of h-Prune on mitochondrial bioenergetics are not a result of a loss of mitochondrial membrane potential or of significant changes in mitochondrial biomass. Overall, our work corroborates the role of polyP in mitochondrial bioenergetics. It also demonstrates a conserved effect of h-Prune on the metabolism of short- and medium-chain polyP (which are the predominant chain lengths found in mammalian cells). The effects of Prune in polyP are most likely exerted via the regulation of the activity of ATP synthase. Our findings pave the way for modifying the levels of polyP in mammalian cells, which could have pharmacological implications in many diseases where dysregulated bioenergetics has been demonstrated.

8.
Front Oncol ; 13: 1175545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529691

RESUMO

Extranodal NK-/T-cell lymphoma (ENKTCL) is a rare and highly aggressive malignancy with significant racial and geographic variations worldwide. In addition to the formerly "nasal-type" initial description, these lymphomas are predominantly extranodal in origin and typically cause vascular damage and tissue destruction, and although not fully understood, Epstein-Barr virus (EBV) has an important role in its pathogenesis. Initial assessment must include a hematopathology review of representative and viable tumor areas without necrosis for adequate immunohistochemistry studies, including EBV-encoded small RNA (EBER) in situ hybridization (ISH). Positron emission tomography with 18-fluorodeoxyglucose (18F-FDG-PET/CT) for accurate staging is essential, and most patients will have localized disease (IE/IIE) at diagnosis. Apart from other T-cell malignancies, the best treatment even for localized cases is combined modality therapy (chemotherapy plus radiotherapy) with non-anthracycline-based regimens. For advanced-stage disease, l-asparaginase-containing regimens have shown improved survival, but relapsed and refractory cases have very poor outcomes. Nowadays, even with a better understanding of pathogenic pathways, up-front therapy is completely based on chemotherapy and radiotherapy, and treatment-related mortality is not low. Future strategies targeting signaling pathways and immunotherapy are evolving, but we need to better identify those patients with dismal outcomes in a pre-emptive way. Given the rarity of the disease, international collaborations are urgently needed, and clinical trials are the way to change the future.

9.
Rev. enferm. Cent.-Oeste Min ; 13: 4956, jun. 2023.
Artigo em Português | LILACS, BDENF - Enfermagem | ID: biblio-1537136

RESUMO

Objetivo: conhecer as representações sociais de gestantes sobre as consultas e assistência prestadas pelo profissio nal enfermeiro no pré-natal. Método: estudo qualitativo ancorado na Teoria das Representações Sociais, realizado com 10 gestantes acompanhadas por enfermeiros da Estratégia de Saúde da Família nas consultas de pré-natal. A coleta de dados ocorreu por meio de entrevista semiestruturada, composta de questões norteadoras e formulário com questões socioeconômicas e dados gineco-obstétricos, seguida de análise estrutural da narração. Resultados: as gestantes, ao elucidarem a representação sobre a consulta com enfermeiro, demonstraram desconhecimento sobre a realização desse tipo de consulta, porém satisfação e confiança em sua atuação, por ser um espaço de cuidado consigo mesmas e com o bebê. Considerações finais: este estudo demonstrou as representações sociais das gestantes acerca das consultas com enfermeiro, relacionadas a satisfação com o atendimento e criação de vínculo com as gestantes, o que favorece a continuidade do cuidado


Objective: to investigate the social representations of pregnant women about prenatal nursing care. Method: based on the Theory of Social Representations, a qualitative study was conducted with 10 pregnant women assisted by nurses from the Family Health Strategy during prenatal consultations. Data were collected by means of a semi-structured interview consisting of guiding questions and a form with socioeconomic questions and obstetric gynecological data, and analyzed by structural narrative analysis. Results: when elaborating on the representation about prenatal nursing, the pregnant women demonstrated ignorance about this type of consultation, but satisfaction and confidence in their performance since this was a space of care for themselves and the baby. Final considerations: this study investigated pregnant women's social representations about nursing consultations related to care satisfaction and bond creation, favoring the continuity of care


Objetivo: conocer las representaciones sociales de las mujeres embarazadas sobre las consultas y asistencias brindadas por profesionales de enfermería en el prenatal. Método: estudio cualitativo basado en la Teoría de las Representaciones Sociales realizado con 10 embarazadas que son acompañadas por enfermeras de la Estrategia Salud Familiar en consultas de prenatal. La recolección de datos ocurrió mediante una entrevista semiestructurada, con preguntas orientadoras, y un formulario con preguntas socioeconómicas y datos ginecoobstétricos, con posterior análisis estructural de la narración. Resultados: Las embarazadas, al dilucidar la representación sobre la consulta de la enfermera, demostraron desconocimiento sobre este tipo de consulta, pero satisfacción y confianza en su actuación, ya que es un espacio de cuidado para ellas y el bebé. Consideraciones finales: este estudio demostró las representaciones sociales de las embarazadas sobre las consultas de enfermería relacionadas con la satisfacción con la atención y establecimiento de un vínculo con las embarazadas, lo que favorece la continuidad de la atención


Assuntos
Humanos , Feminino , Gravidez , Cuidado Pré-Natal , Enfermagem , Cuidados de Enfermagem
10.
Int J Mol Sci ; 24(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37047304

RESUMO

Sickle cell disease (SCD) is an inherited blood disorder caused by a ß-globin gene point mutation that results in the production of sickle hemoglobin that polymerizes upon deoxygenation, causing the sickling of red blood cells (RBCs). RBC deformation initiates a sequence of events leading to multiple complications, such as hemolytic anemia, vaso-occlusion, chronic inflammation, and tissue damage. Macrophages participate in extravascular hemolysis by removing damaged RBCs, hence preventing the release of free hemoglobin and heme, and triggering inflammation. Upon erythrophagocytosis, macrophages metabolize RBC-derived hemoglobin, activating mechanisms responsible for recycling iron, which is then used for the generation of new RBCs to try to compensate for anemia. In the bone marrow, macrophages can create specialized niches, known as erythroblastic islands (EBIs), which regulate erythropoiesis. Anemia and inflammation present in SCD may trigger mechanisms of stress erythropoiesis, intensifying RBC generation by expanding the number of EBIs in the bone marrow and creating new ones in extramedullary sites. In the current review, we discuss the distinct mechanisms that could induce stress erythropoiesis in SCD, potentially shifting the macrophage phenotype to an inflammatory profile, and changing their supporting role necessary for the proliferation and differentiation of erythroid cells in the disease. The knowledge of the soluble factors, cell surface and intracellular molecules expressed by EBI macrophages that contribute to begin and end the RBC's lifespan, as well as the understanding of their signaling pathways in SCD, may reveal potential targets to control the pathophysiology of the disease.


Assuntos
Anemia Falciforme , Linfo-Histiocitose Hemofagocítica , Humanos , Eritropoese , Eritrócitos , Macrófagos/metabolismo , Inflamação/metabolismo
11.
Cell Mol Neurobiol ; 43(3): 1163-1180, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35674974

RESUMO

Methylmalonic acidemia is an organic acidemia caused by deficient activity of L-methylmalonyl-CoA mutase or its cofactor cyanocobalamin and it is biochemically characterized by an accumulation of methylmalonic acid (MMA) in tissue and body fluids of patients. The main clinical manifestations of this disease are neurological and observable symptoms during metabolic decompensation are encephalopathy, cerebral atrophy, coma, and seizures, which commonly appear in newborns. This study aimed to investigate the toxic effects of MMA in a glial cell line presenting astrocytic features. Astroglial C6 cells were exposed to MMA (0.1-10 mM) for 24 or 48 h and cell metabolic viability, glucose consumption, and oxygen consumption rate, as well as glutamate uptake and ATP content were analyzed. The possible preventive effects of bezafibrate were also evaluated. MMA significantly reduced cell metabolic viability after 48-h period and increased glucose consumption during the same period of incubation. Regarding the energy homeostasis, MMA significantly reduced respiratory parameters of cells after 48-h exposure, indicating that cell metabolism is compromised at resting and reserve capacity state, which might influence the cell capacity to meet energetic demands. Glutamate uptake and ATP content were also compromised after exposure to MMA, which can be influenced energy metabolism impairment, affecting the functionality of the astroglial cells. Our findings suggest that these effects could be involved in the pathophysiology of neurological dysfunction of this disease. Methylmalonic acid compromises mitochondrial functioning leading to reduced ATP production and reduces glutamate uptake by C6 astroglial cells.


Assuntos
Glioma , Ácido Glutâmico , Ratos , Animais , Ácido Glutâmico/metabolismo , Ácido Metilmalônico/toxicidade , Respiração Celular , Trifosfato de Adenosina/metabolismo
12.
Front Cell Dev Biol ; 11: 1302585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161329

RESUMO

Introduction: Inorganic polyphosphate (polyP) is an ancient polymer which is extremely well-conserved throughout evolution, and found in every studied organism. PolyP is composed of orthophosphates linked together by high-energy bonds, similar to those found in ATP. The metabolism and the functions of polyP in prokaryotes and simple eukaryotes are well understood. However, little is known about its physiological roles in mammalian cells, mostly due to its unknown metabolism and lack of systematic methods and effective models for the study of polyP in these organisms. Methods: Here, we present a comprehensive set of genetically modified cellular models to study mammalian polyP. Specifically, we focus our studies on mitochondrial polyP, as previous studies have shown the potent regulatory role of mammalian polyP in the organelle, including bioenergetics, via mechanisms that are not yet fully understood. Results: Using SH-SY5Y cells, our results show that the enzymatic depletion of mitochondrial polyP affects the expression of genes involved in the maintenance of mitochondrial physiology, as well as the structure of the organelle. Furthermore, this depletion has deleterious effects on mitochondrial respiration, an effect that is dependent on the length of polyP. Our results also show that the depletion of mammalian polyP in other subcellular locations induces significant changes in gene expression and bioenergetics; as well as that SH-SY5Y cells are not viable when the amount and/or the length of polyP are increased in mitochondria. Discussion: Our findings expand on the crucial role of polyP in mammalian mitochondrial physiology and place our cell lines as a valid model to increase our knowledge of both mammalian polyP and mitochondrial physiology.

13.
Clin Epigenetics ; 14(1): 180, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536430

RESUMO

Nodal mature T-cell lymphomas (nMTCL) comprises a heterogeneous group of rare malignancies with aggressive biological behavior and poor prognosis. Epigenetic phenomena, including mutations in genes that control DNA methylation and histone deacetylation, in addition to inactivating mutations in the RhoA GTPase, play a central role in its pathogenesis and constitute potential new targets for therapeutic intervention. Tumor mutational burden (TMB) reflects the process of clonal evolution, predicts response to anti-cancer therapies and has emerged as a prognostic biomarker in several solid neoplasms; however, its potential prognostic impact remains unknown in nMTCL. In this study, we conducted Sanger sequencing of formalin-fixed paraffin-embedded (FFPE) diagnostic tumor samples using a target-panel to search for recurrent mutations involving the IDH-1/IDH-2, TET-2, DNMT3A and RhoA genes in 59 cases of nMTCL. For the first time, we demonstrated that high-TMB, defined by the presence of ≥ two mutations involving the aforementioned genes, was associated with decreased overall survival in nMTCL patients treated with CHOP-like regimens. Additionally, high-TMB was correlated with bulky disease, lower overall response rate, and higher mortality. Future studies using larger cohorts may validate our preliminary results that indicate TMB as a potential molecular biomarker associated with adverse prognosis in nMTCL.


Assuntos
Linfoma de Células T Periférico , Neoplasias , Humanos , Metilação de DNA , Biomarcadores Tumorais/genética , Neoplasias/genética , Prognóstico , Linfoma de Células T Periférico/genética , Mutação , Genes Reguladores , Epigênese Genética , Proteína rhoA de Ligação ao GTP/genética
14.
Sci Rep ; 12(1): 20557, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446856

RESUMO

Extranodal natural-killer/T-cell lymphoma (ENKTL) is a rare and aggressive Epstein-Barr virus related mature T-cell and natural-killer malignancy. Although highly prevalent in South America, few studies covering data from this geographic location have been published. Therefore, this study aims to report clinical characteristics, prognostic factors, and outcomes in a multicenter cohort of ENKTL patients from Brazil. This retrospective, observational and multicenter study included 98 ENKTL patients treated during two decades in Brazil. Data were extracted from the T-Cell Brazil Project database. In our cohort, 59/98 patients (60.2%) were male, with a median age of 50 years. Sixty-two patients (63.3%) had B-symptoms, 26/98 (26.5%) had Eastern Cooperative Oncology Group scale ≥ 2; 16/98 (16.3%) presented extranasal disease and 34.7% (34/98) were advanced-stage (Ann Arbor/Cotswolds III/IV). The median follow-up for the whole cohort was 49 months, with an estimated 2-year overall survival (OS) and progression-free survival (PFS) of 51.1% and 17.7%, respectively. In early-stage disease (IE/IIE), the median OS was 21.8 months for patients treated with concurrent radiotherapy plus chemotherapy (CCRT-VIPD [etoposide/vp-16, ifosfamide, cisplatin and dexamethasone), 16.2 months for sequential chemoradiotherapy (SCRT) followed by asparaginase-based regimens, and 56.7 months for SCRT followed by CHOP-like (cyclophosphamide, doxorrubicin, vincristine and prednisone) treatments, p = 0.211. CCRT was associated with higher rates of early-mortality, hematological toxicity, and mucositis. Median OS was 8.2 months for patients with advanced-stage disease receiving regimens containing asparaginase compared to 3.2 months for anthracycline-based therapy, p = 0.851. Chemo-radiotherapy (CRT) regimens demonstrated better OS (p = 0.001) and PFS (p = 0.007) than chemotherapy alone. Multivariate analysis revealed anemia, relapsed/refractory (R/R) disease and radiotherapy omission as poor outcome predictors for OS. Lymphopenia and radiotherapy omission adversely affected PFS. Concerning progression of disease within 24-months (POD-24), clinical stage III/IV was a poor outcome predictor. In this real-life Brazilian cohort, ENKTL presented dismal outcomes. Radiation therapy was an independent factor for increased OS and PFS, but CCRT regimens were associated with higher toxicities. Polychemotherapy based on anti-multi drug resistant agents was not associated with survival benefit in either early or advanced-stage disease in our patient cohort.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma Extranodal de Células T-NK , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Linfoma Extranodal de Células T-NK/radioterapia , Brasil/epidemiologia , Asparaginase , Estudos Retrospectivos , Herpesvirus Humano 4/genética , Etoposídeo
15.
Radiat Oncol ; 17(1): 171, 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273167

RESUMO

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a rare and aggressive malignancy. Although potentially curable, its prognosis remains dismal. Its treatment is based on high-doses of methotrexate (HD-MTX) and rituximab, followed by consolidation therapy with whole-brain radiotherapy (WBRT) or autologous stem cell transplantation (ASCT). Currently, there is no consensus about the best consolidation strategy, but better outcomes with ASCT are obtained with conditioning regimens based on thiotepa, a high-cost drug with restricted use in resource-constrained settings. Latin American data on clinical outcomes, prognostic factors, and therapeutic management in PCNSL are virtually unknown. METHODS: This is a retrospective, observational, and single-center study involving 47-Brazilian patients with PCNSL. We aim to assess outcomes, determine predictors of survival, and compare responses, as well as toxicities in patients consolidated with chemotherapy alone versus chemotherapy plus WBRT. RESULTS: The median age at diagnosis was 59 years (24-88 years), and 53.1% were male. LDH ≥ UVN occurred in 44.7%, ECOG ≥ 2 in 67.6%, and 34.1% had multifocal disease. Hemiparesis was the main clinical presentation, observed in 55.3%, 51.0% had intermediate-/high-risk IELSG prognostic score, and 57.6% had an ABC-like phenotype by IHC. With a median follow-up of 24.4 months, estimated 5-year OS and PFS were 45.5% and 36.4%, respectively. Among 40 patients treated with HD-MTX-based induction, estimated 2-year OS was 85.8% for those consolidated with WBRT plus HIDAC versus only 41.5% for those consolidated with HIDAC alone (p < 0.001). Hematologic and non-hematologic toxicities were not significant, and severe cognitive impairment occurred in only 6.3% (3/47) of cases, all of them treated with WBRT. Age < 60 years, Hb ≥ 120 g/L and WBRT consolidation were associated with increased OS, however, LDH ≥ UVN, hypoalbuminemia, ECOG ≥ 2, Karnofsky PS < 70 and intermediate-/high-risk Barcelona score were associated with decreased OS. CONCLUSION: Combined consolidation therapy (CCT) based on WBRT plus HIDAC was associated with increased OS in PCNSL compared to isolated consolidation therapy (ICT) based on HIDAC alone. Here, severe late neurotoxicity was uncommon with this approach. These data suggest that WBRT may be an effective and safe alternative to ASCT for consolidation therapy in PCNSL, particularly in resource-constrained settings, where access to thiotepa for pre-ASCT conditioning is not universal.


Assuntos
Neoplasias do Sistema Nervoso Central , Transplante de Células-Tronco Hematopoéticas , Linfoma , Masculino , Feminino , Humanos , Transplante Autólogo , Tiotepa/uso terapêutico , Metotrexato/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/radioterapia , Rituximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Transplante de Células-Tronco/efeitos adversos , Terapia Combinada , Encéfalo/patologia , Sistema Nervoso Central/patologia
16.
Hematol., Transfus. Cell Ther. (Impr.) ; 44(4): 574-581, Oct.-dec. 2022. graf
Artigo em Inglês | LILACS | ID: biblio-1421539

RESUMO

ABSTRACT The development of red blood cells (RBCs), or erythropoiesis, occurs in specialized niches in the bone marrow, called erythroblastic islands, composed of a central macrophage surrounded by erythroblasts at different stages of differentiation. Upon anemia or hypoxemia, erythropoiesis extends to extramedullary sites, mainly spleen and liver, a process known as stress erythropoiesis, leading to the expansion of erythroid progenitors, iron recruitment and increased production of reticulocytes and mature RBCs. Macrophages are key cells in both homeostatic and stress erythropoiesis, providing conditions for erythroid cells to survive, proliferate and differentiate. During RBCs aging and injury, macrophages play a fundamental role again, performing the clearance of these cells and recycling iron for new erythroblasts in development. Thus, macrophages are crucial components of the RBCs turnover and in this review, we aimed to cover the main known mechanisms involved in the process of birth and death of RBCs, highlighting the importance of macrophage functions in the whole RBC lifecycle.


Assuntos
Eritrócitos , Macrófagos , Eritropoese
17.
Photodiagnosis Photodyn Ther ; 39: 103015, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35843562

RESUMO

Ultraviolet (UV) light can inactivate SARS-CoV-2. However, the practicality of UV light is limited by the carcinogenic potential of mercury vapor-based UV lamps. Recent advances in the development of krypton chlorine (KrCl) excimer lamps hold promise, as these emit a shorter peak wavelength (222 nm), which is highly absorbed by the skin's stratum corneum and can filter out higher wavelengths. In this sense, UV 222 nm irradiation for the inactivation of virus particles in the air and surfaces is a potentially safer option as a germicidal technology. However, these same physical properties make it harder to reach microbes present in complex solutions, such as saliva, a critical source of SARS-CoV-2 transmission. We provide the first evaluation for using a commercial filtered KrCl excimer light source to inactivate SARS-CoV-2 in saliva spread on a surface. A conventional germicidal lamp (UV 254 nm) was also evaluated under the same condition. Using plaque-forming units (PFU) and Median Tissue Culture Infectious Dose (TCID50) per milliliter we found that 99.99% viral clearance (LD99.99) was obtained with 106.3 mJ/cm2 of UV 222 nm for virus in DMEM and 2417 mJ/cm2 for virus in saliva. Additionally, our results showed that the UV 254 nm had a greater capacity to inactivate the virus in both vehicles. Effective (after discounting light absorption) LD99.99 of UV 222 nm on the virus in saliva was ∼30 times higher than the value obtained with virus in saline solution (PBS), we speculated that saliva might be protecting the virus from surface irradiation in ways other than just by intensity attenuation of UV 222 nm. Due to differences between UV 222/254 nm capacities to interact and be absorbed by molecules in complex solutions, a higher dose of 222 nm will be necessary to reduce viral load in surfaces with contaminated saliva.


Assuntos
COVID-19 , Fotoquimioterapia , Desinfecção/métodos , Humanos , Fotoquimioterapia/métodos , SARS-CoV-2 , Saliva , Raios Ultravioleta
18.
Clin Lymphoma Myeloma Leuk ; 22(11): 812-824, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35869020

RESUMO

BACKGROUND: Nodal peripheral T-cell lymphoma (nPTCL) constitute a heterogeneous group of neoplasms with aggressive behavior and poor-survival. They are more prevalent in Latin America and Asia, although data from Brazil are scarce. Its primary therapy is still controversial and ineffective. Therefore, we aim to describe clinical-epidemiological characteristics, outcomes, predictors factors for survival and compare the results of patients treated with CHOP and CHOEP regimens. METHODS: Retrospective, observational and single-center study involving 124 nPTCL patients from Brazil treated from 2000 to 2019. RESULTS: With a median follow-up of 23.7 months, the estimated 2-year overall survival (OS) and progression-free survival (PFS) were 59.2% and 37.3%, respectively. The median age was 48.5 years and 57.3% (71/124) were male, 81.5% (101/124) had B-symptoms, 88.7% (110/124) had advanced disease (stage III/IV) and 58.1% (72/124) presented International Prognostic Index (IPI) score ≥3, reflecting a real-life cohort. ORR to first-line therapy was 58.9%, 37.9% (N = 47) received CHOP-21 and 35.5% (N = 44) were treated with CHOEP-21; 30.1% (37/124) underwent to consolidation with involved field radiotherapy (IF-RT) and 32.3% (40/124) were consolidated with autologous hematopoietic stem cell transplantation (ASCT). The overall response rate (ORR) was similar for CHOP-21 (76.6%) and CHOEP-21 (65.9%), P = .259. Refractory disease was less frequent in the CHOEP-21 group (4.5% vs. 21.2%, P = .018). However, few patients were able to complete 6-cycles of CHOEP-21 (31.8%) than to CHOP-21 (61.7%), P = .003. Delays ≥2 weeks among the cycles of chemotherapy were more frequent for patients receiving CHOEP-21 (43.1% vs. 10.6%), P = .0004, as well as the toxicities, including G3-4 neutropenia (88% vs. 57%, P = .001), febrile neutropenia (70% vs. 38%, P = .003) and G3-4 thrombocytopenia (63% vs. 27%, P = .0007). The 2-year OS was higher for CHOP (78.7%) than CHOEP group (61.4%), P = .05, as well as 2-year PFS (69.7% vs. 25.0%, P < .0001). In multivariate analysis, high LDH (HR 3.38, P = .007) was associated with decreased OS. CR at first line (HR: 0.09, P < .001) and consolidation with ASCT (HR: 0.08, P = .015) were predictors of increased OS. CONCLUSION: In the largest cohort of nPTCL from Latin America, patients had poor survival and high rate of chemo-resistance. In our cohort, the addition of etoposide to the CHOP-21 backbone showed no survival benefit and was associated with high-toxicity and frequent treatment interruptions. Normal LDH values, obtaintion of CR and consolidation with ASCT were independent factors associated with better outcomes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma de Células T Periférico , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Etoposídeo , Brasil/epidemiologia , Estudos Retrospectivos , Vincristina/efeitos adversos , Ciclofosfamida/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Prednisona/efeitos adversos , Doxorrubicina/efeitos adversos , Prednisolona/uso terapêutico , Linfoma de Células T Periférico/patologia
19.
Rev. Bras. Saúde Mater. Infant. (Online) ; 22(1): 127-135, Jan.-Mar. 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1376204

RESUMO

Abstract Objectives: to investigate sociodemographic and economic factors associated with food insecurity among pregnant women assisted by the universal healthcare network of Lavras, Minas Gerais. Methods: a cross-sectional study investigated socioeconomic and demographic, obstetric, and nutritional conditions experienced by pregnant women. Households in which pregnant women lived were classified as food secure or food insecure using the Brazilian Food Insecurity Scale. Prevalence estimates and prevalence ratios with 95% confidence intervals were generated to test for associations between food insecurity and several socioeconomic and demographic indicators using Poisson regression analysis. Results: among 173 pregnant women who participated in the study, 48% lived in households with some level of food insecurity. Adjusted models showed that pregnant women living in food-insecure households had higher prevalence ratios of lower education attainment (aPR = 1.43, CI95% = 1.07-1.91), woman being the head of the household (aPR = 1.39, CI95% = 1.02-1.87), having family monthly income lower than 1 ½ MW (aPR = 1.68, CI95% = 1.11-2.52) and participating in the government cash transfer program (aPR = 1.47, CI95% = 1.08-1.99). Conclusions: the high prevalence of food insecurity in pregnant women assisted by the public healthcare system was associated with structural social factors. Results of this study will contribute to develop an intersectoral health and nutrition policy in order to promote food security among marginalized communities and vulnerable populations, such as pregnant women.


Resumo Objetivos: investigar fatores sociodemográficos e econômicos associados à insegurança alimentar entre gestantes atendidas pelo sistema único de saúde de Lavras - Minas Gerais. Métodos: características socioeconômicas, demográficas, obstétricas e nutricionais de gestantes foram coletadas em estudo transversal. Os domicílios das gestantes foram classificados em segurança ou insegurança alimentar utilizando a Escala Brasileira de Insegurança Alimentar. Estimativas de prevalência e razão de prevalência com intervalos de confiança de 95%, testaram associações entre insegurança alimentar e indicadores socioeconômicos e demográficos utilizando modelos de Poisson. Resultados: entre as 173 gestantes participantes deste estudo, 48% viviam em domicílios com algum nível insegurança alimentar (IA). Modelos ajustados indicaram que gestantes em IAapresentaram maior prevalência de escolaridade inferior a oito anos de estudo (aRP = 1.39, IC95% = 1.07-1.91), ser chefe de família (aRP = 1.39, IC95% = 1.02-1.87), ter renda mensal inferior a 1½ salário mínimo (aRP = 1.68, IC95% =1.11-2.25), e ser participante do Bolsa Família (aRP = 1.47, IC95% = 1.08-1.99). Conclusão: a alta prevalência de insegurança alimentar em gestantes do sistema público de saúde de Lavras está associado a fatores socio-estruturais. Os resultados desta pesquisapoderão contribuir com o desenvolvimento de políticas intersetoriais de saúde e nutrição para a promoção da segurança alimentar entre comunidades marginalizadas e populações vulneráveis.


Assuntos
Humanos , Feminino , Gravidez , Fatores Socioeconômicos , Estado Nutricional , Gestantes , Razão de Prevalências , Insegurança Alimentar/economia , Fatores Sociodemográficos , Sistema Único de Saúde , Brasil , Disparidades nos Níveis de Saúde
20.
J Nutr Biochem ; 103: 108969, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35196578

RESUMO

Postnatal early overfeeding (PO) is a risk factor for cardiometabolic disorders. However, remains unknown the cardiac effects in the second generation from postnatal overfed dams. Our aim was to investigate the effects of maternal PO on cardiac parameters in second generation (F2) offspring. For this, pregnant Wistar rats (F0) were divided into two groups: normal litter (NL, 9 pups) and small litter (SL, 3 pups). At P70, female offspring (F1) of both groups were mated with non-PO male rats. At P21 male and female F2 offspring (NLO and SLO) were weaned, and at P45 they were euthanized to evaluate the cardiac function and sample collection. Male and female SLO showed increased body weight, food intake and adiposity. Blood estradiol levels were increased in the male SLO and decreased in the female SLO. Blood testosterone levels increased in SLO females, but not change in SLO male rats. Although SLO offspring presented cardiac hypertrophy, only males had ex vivo functional impairments, such as reduction of the intraventricular systolic pressure and dP/dt. Male and female SLO had increased interstitial fibrosis; however, only the male SLO had increased perivascular fibrosis. In addition, only male rats from SLO group had decreased AKT and Type 2 Ang-2 receptor, increased catalase and type alpha estrogenic receptor protein levels. Maternal PO leads to obese phenotype and alters sex-steroid levels in both male and female offspring. Although both sexes showed cardiac hypertrophy, only male offspring showed cardiac dysfunction, which may be related with Ang2 and AKT signaling impairments.


Assuntos
Cardiopatias , Proteínas Proto-Oncogênicas c-akt , Animais , Peso Corporal , Cardiomegalia/etiologia , Feminino , Fibrose , Cardiopatias/etiologia , Hormônios , Masculino , Obesidade , Gravidez , Ratos , Ratos Wistar
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