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1.
Nat Commun ; 15(1): 2569, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519473

RESUMO

The B cell response in the germinal centre (GC) reaction requires a unique bioenergetic supply. Although mitochondria are remodelled upon antigen-mediated B cell receptor stimulation, mitochondrial function in B cells is still poorly understood. To gain a better understanding of the role of mitochondria in B cell function, here we generate mice with B cell-specific deficiency in Tfam, a transcription factor necessary for mitochondrial biogenesis. Tfam conditional knock-out (KO) mice display a blockage of the GC reaction and a bias of B cell differentiation towards memory B cells and aged-related B cells, hallmarks of an aged immune response. Unexpectedly, blocked GC reaction in Tfam KO mice is not caused by defects in the bioenergetic supply but is associated with a defect in the remodelling of the lysosomal compartment in B cells. Our results may thus describe a mitochondrial function for lysosome regulation and the downstream antigen presentation in B cells during the GC reaction, the dysruption of which is manifested as an aged immune response.


Assuntos
Linfócitos B , Mitocôndrias , Camundongos , Animais , Mitocôndrias/genética , Centro Germinativo , Camundongos Knockout , Ativação Linfocitária
2.
Cells ; 12(23)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067115

RESUMO

Chronic lymphocytic leukemia (CLL) is a hematologic malignancy characterized by progressive accumulation of a rare population of CD5+ B-lymphocytes in peripheral blood, bone marrow, and lymphoid tissues. CLL exhibits remarkable clinical heterogeneity, with some patients presenting with indolent disease and others progressing rapidly to aggressive CLL. The significant heterogeneity of CLL underscores the importance of identifying novel prognostic markers. Recently, the RAS-related gene RRAS2 has emerged as both a driver oncogene and a potential marker for CLL progression, with higher RRAS2 expression associated with poorer disease prognosis. Although missense somatic mutations in the coding sequence of RRAS2 have not been described in CLL, this study reports the frequent detection of three somatic mutations in the 3' untranslated region (3'UTR) affecting positions +26, +53, and +180 downstream of the stop codon in the mRNA. An inverse relationship was observed between these three somatic mutations and RRAS2 mRNA expression, which correlated with lower blood lymphocytosis. These findings highlight the importance of RRAS2 overexpression in CLL development and prognosis and point to somatic mutations in its 3'UTR as novel mechanistic clues. Our results may contribute to the development of targeted therapeutic strategies and improved risk stratification for CLL patients.


Assuntos
Leucemia Linfocítica Crônica de Células B , Linfocitose , Proteínas Monoméricas de Ligação ao GTP , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Regiões 3' não Traduzidas/genética , Linfocitose/genética , Linfocitose/diagnóstico , Linfocitose/patologia , Linfócitos B/patologia , Mutação/genética , Proteínas de Membrana/genética , Proteínas Monoméricas de Ligação ao GTP/genética
3.
Cancer Control ; 30: 10732748231175256, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37148308

RESUMO

PURPOSE: Identifying actionable oncogenic mutations have changed the therapeutic landscape in different types of tumors. This study investigated the utility of comprehensive genomic profiling (CGP), a hybrid capture-based next-generation sequencing (NGS) assay, in clinical practice in a developing country. METHODS: In this retrospective cohort study, CGP was performed on clinical samples from patients with different solid tumors recruited between December 2016 and November 2020, using hybrid capture-based genomic profiling, at the individual treating physicians' request in the clinical care for therapy decisions. Kaplan-Meier survival curves were estimated to characterize the time-to-event variables. RESULTS: Patients median age was 61 years (range: 14-87 years), and 64.7% were female. The most common histological diagnosis was lung primary tumors, with 90 patients corresponding to 52.9% of the samples (95% CI 45.4-60.4%). Actionable mutations with FDA-approved medications for specific alterations correspondent to tumoral histology were identified in 58 cases (46.4%), whereas other alterations were detected in 47 different samples (37.6%). The median overall survival was 15.5 months (95% CI 11.7 months-NR). Patients who were subjected to genomic evaluation at diagnosis reached a median overall survival of 18.3 months (95% CI 14.9 months-NR) compared to 14.1 months (95% CI 11.1 months-NR) in patients who obtained genomic evaluation after tumor progression and during standard treatment (P = .7). CONCLUSION: CGP of different types of tumors identifies clinically relevant genomic alterations that have benefited from targeted therapy and improve cancer care in a developing country to guide personalized treatment to beneficial outcomes of cancer patients.


Assuntos
Países em Desenvolvimento , Neoplasias Pulmonares , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Neoplasias Pulmonares/patologia , Mutação , Genômica , Sequenciamento de Nucleotídeos em Larga Escala
4.
Cancers (Basel) ; 15(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36765602

RESUMO

Unlike classical RAS genes, oncogenic mutations on RRAS2 are seldomly found in human cancer. By contrast, RRAS2 is frequently found overexpressed in a number of human tumors, including B and T cell lymphomas, breast, gastric, head and neck cancers. In this regard, we have recently shown that overexpression of wild-type RRAS2 drives the formation of both chronic lymphocytic leukemia (CLL) and breast cancer in mice. In support for the relevance of overexpression of wild type RRAS2 in human cancer, we have found that RRAS2 expression is influenced by the presence of a specific single nucleotide polymorphism (SNP) located in the 3'-untranslated region (UTR) of the RRAS2 mRNA. Perhaps more importantly, the presence of the alternate C, rather than the G allele, at the RRAS2 SNP designated as rs8570 is also associated with worse patient prognosis in CLL. This indicates that the detection of this SNP allelic variants can be informative to predict RRAS2 expression levels and disease long-term evolution in patients. Here, we describe a polymerase chain reaction (PCR)-based method that facilitates the rapid and easy determination of G and C allelic variants of the SNP. Using this approach, we confirm that the C allelic variant is associated with higher expression levels of RRAS2 transcripts and poor patient prognosis. However, we have also found that expression of the C allelic variants correlates with better response to ibrutinib, a Bruton kinase inhibitor commonly used in CLL treatments. This suggests that this method for detecting the RRAS2 rs8570 SNP might be a useful as a tool to predict both patient prognosis and response to targeted therapy in CLL.

5.
J Environ Manage ; 323: 116148, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36088761

RESUMO

Biochar (BP) obtained from palm fiber wastes was combined with H2O2, peroxymonosulfate (PMS), or persulfate (PDS) to treat valsartan, acetaminophen, and cephalexin in water. BP activated PMS and PDS but no H2O2. Computational calculations indicated that interactions of PMS and PDS with BP are more favored than those with HP. The highest synergistic effect was obtained for the removal of valsartan by BP + PMS. This carbocatalytic process was optimized, evaluating the effects of pH, BP dose, and peroxymonosulfate concentration, and minimizing the oxidant quantity to decrease costs and environmental impacts of the process. SO4•-, HO•, 1O2, and O2•- were the agents involved in the degradation of the pharmaceuticals. The reusability of BP was tested, showing that the carbocatalytic process removed ∼80% of target pollutants after 120 min of treatment even at the fourth reuse cycle. Also, the process decreased the phytotoxicity of the treated sample. Simulated hospital wastewater was treated and its components induced competing effects, but the system achieved the target pharmaceuticals removal in this matrix. Additionally, the analysis of environmental impact using a life cycle assessment unraveled that the carbocatalytic process had a carbon footprint of 2.87 Kg CO2-Eq, with the biochar preparation (which involves the use of ZnCl2 and electric energy consumption) as the main hotspot in the process.


Assuntos
Oxidantes , Poluentes Químicos da Água , Acetaminofen , Dióxido de Carbono/análise , Cefalexina/análise , Carvão Vegetal , Peróxidos , Preparações Farmacêuticas , Valsartana/análise , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise
6.
Mol Cancer ; 21(1): 35, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35120522

RESUMO

BACKGROUND: Chronic lymphocytic leukemia (CLL) is the most frequent, and still incurable, form of leukemia in the Western World. It is widely accepted that cancer results from an evolutionary process shaped by the acquisition of driver mutations which confer selective growth advantage to cells that harbor them. Clear examples are missense mutations in classic RAS genes (KRAS, HRAS and NRAS) that underlie the development of approximately 13% of human cancers. Although autonomous B cell antigen receptor (BCR) signaling is involved and mutations in many tumor suppressor genes and oncogenes have been identified, an oncogenic driver gene has not still been identified for CLL. METHODS: Conditional knock-in mice were generated to overexpress wild type RRAS2 and prove its driver role. RT-qPCR analysis of a human CLL sample cohort was carried out to measure RRAS2 transcriptional expression. Sanger DNA sequencing was used to identify a SNP in the 3'UTR region of RRAS2 in human CLL samples. RNAseq of murine CLL was carried out to identify activated pathways, molecular mechanisms and to pinpoint somatic mutations accompanying RRAS2 overexpression. Flow cytometry was used for phenotypic characterization and shRNA techniques to knockdown RRAS2 expression in human CLL. RESULTS: RRAS2 mRNA is found overexpressed in its wild type form in 82% of the human CLL samples analyzed (n = 178, mean and median = 5-fold) as well as in the explored metadata. A single nucleotide polymorphism (rs8570) in the 3'UTR of the RRAS2 mRNA has been identified in CLL patients, linking higher expression of RRAS2 with more aggressive disease. Deliberate overexpression of wild type RRAS2 in mice, but not an oncogenic Q72L mutation in the coding sequence, provokes the development of CLL. Overexpression of wild type RRAS2 in mice is accompanied by a strong convergent selection of somatic mutations in genes that have been identified in human CLL. R-RAS2 protein is physically bound to the BCR and mediates BCR signals in CLL. CONCLUSIONS: The results indicate that overexpression of wild type RRAS2 is behind the development of CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Proteínas Monoméricas de Ligação ao GTP , Animais , Genes ras , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas de Membrana/genética , Camundongos , Proteínas Monoméricas de Ligação ao GTP/genética , Mutação , Receptores de Antígenos de Linfócitos B , Transdução de Sinais
7.
Front Immunol ; 12: 669965, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34489928

RESUMO

Introduction: Animal studies and preclinical studies in cancer patients suggest that the induction of immunogenic cell death (ICD) by neoadjuvant chemotherapy with doxorubicin and cyclophosphamide (NAC-AC) recovers the functional performance of the immune system. This could favor immunotherapy schemes such as the administration of antigen-free autologous dendritic cells (DCs) in combination with NAC-AC to profit as cryptic vaccine immunogenicity of treated tumors. Objective: To explore the safety and immunogenicity of autologous antigen-free DCs administered to breast cancer patients (BCPs) in combination with NAC-AC. Materials and Methods: A phase I/II cohort clinical trial was performed with 20 BCPs treated with NAC-AC [nine who received DCs and 11 who did not (control group)]. The occurrence of adverse effects and the functional performance of lymphocytes from BCPs before and after four cycles of NAC-AC receiving DCs or not were assessed using flow cytometry and compared with that from healthy donors (HDs). Flow cytometry analysis using manual and automated algorithms led us to examine functional performance and frequency of different lymphocyte compartments in response to a stimulus in vitro. This study was registered at clinicaltrials.gov (NCT03450044). Results: No grade II or higher adverse effects were observed associated with the transfer of DCs to patients during NAC-AC. Interestingly, in response to the in vitro stimulation, deficient phosphorylation of Zap70 and AKT proteins observed before chemotherapy in most patients' CD4 T cells significantly recovered after NAC-AC only in patients who received DCs. Conclusions: The transfer of autologous DCs in combination with NAC-AC in BCPs is a safe procedure. That, in BCPs, the administration of DCs in combination with NAC-AC favors the recovery of the functional capacity of T cells suggests that this combination may potentiate the adjuvant effect of ICD induced by NAC-AC on T cells and, hence, potentiate the immunogenicity of tumors as cryptic vaccines.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Vacinas Anticâncer/uso terapêutico , Células Dendríticas/transplante , Imunoterapia Adotiva , Linfócitos do Interstício Tumoral/imunologia , Terapia Neoadjuvante , Linfócitos T/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/imunologia , Quimioterapia Adjuvante , Colômbia , Ciclofosfamida/uso terapêutico , Células Dendríticas/imunologia , Doxorrubicina/uso terapêutico , Feminino , Humanos , Imunoterapia Adotiva/efeitos adversos , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Microambiente Tumoral
8.
Ann Clin Microbiol Antimicrob ; 20(1): 39, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030702

RESUMO

BACKGROUND: There is limited and controverting evidence looking at possible associations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copies and patient variables in large cohorts of symptomatic and asymptomatic patients. METHODS: We studied 2275 symptomatic and asymptomatic patients from Colombia with coronavirus disease 2019 (COVID-19) and analyzed the associations between RT-PCR cycle threshold (Ct) value with gender, age, comorbidities, symptomatology, and disease severity. RESULTS: 15.4 % of the samples (n = 428) reported at least one comorbidity. There were 2011 symptomatic cases (72.4 %), being the most common reported symptom cough (57.2 %, n = 1586). Respiratory distress was present in 21.4 % of patients (n = 595), and 435 patients (15.6 %) required hospital admission. We observed that patients with no prior medical history harbored higher RNA copies than patients with comorbidities (p = 0.02). No significant differences in RNA copies were observed between symptomatic and asymptomatic patients (p = 0.82). Strong correlations were detected between Ct values and the presence of odynophagia (p = 0.03), diarrhea (p = 0.04), and headache (p = 0.0008). An inverse association was found between RNA copy number and markers of disease severity, namely, respiratory distress (P < 0.0001) and hospitalization requirement (P < 0.0001). CONCLUSIONS: SARS-CoV-2 RT-PCR cycle thresholds reveal strong associations with a prior medical history, specific symptomatology, and disease severity markers. Further research controlling potential confounding variables needs to be conducted to evaluate the nature and usefulness of these associations in managing COVID-19 patients.


Assuntos
COVID-19/patologia , RNA Viral/sangue , SARS-CoV-2/genética , Carga Viral/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , Teste de Ácido Nucleico para COVID-19 , Criança , Pré-Escolar , Colômbia , Comorbidade , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
9.
Bioresour Technol ; 326: 124753, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33545628

RESUMO

Acetaminophen (ACE), cephalexin (CPX), and valsartan (VAL) are recognized water pollutants, which can be removed by adsorption. Herein, the removal of these pharmaceuticals using a biochar (BP), prepared from oil palm fiber, was tested. It was studied the structural effects of the pharmaceuticals and biochar on the adsorption process supported by experimental and computational results, plus characterizations of the material. The biochar has 76.05 m2 g-1 of surficial area, and carboxylic groups (1.343 mmol g-1) predominantly. The maximum adsorption uptakes were 7.3, 7.9, and 23.85 mg g-1 for ACE, CPX, and VAL, respectively; following pseudo-second-order kinetics. The best pollutants removal was obtained at acidic pH (3.0). Computational analyses indicated that oxygenated groups of BP (able to generate H-bond interactions) influenced the adsorption of pharmaceuticals. It can be remarked that BP is a low-cost adsorbent synthesized easily from wastes, with high feasibility to remove pharmaceutical structures from water.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Água , Poluentes Químicos da Água/análise
10.
BMC Complement Altern Med ; 8: 60, 2008 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-19017389

RESUMO

BACKGROUND: There is ethnopharmacological evidence that Petiveria alliacea can have antitumor activity; however, the mechanism of its cytotoxic activity is not well understood. We assessed multiple in vitro biological activities of an ethyl acetate soluble plant fraction over several tumor cell lines. METHODS: Tumor cell lines were evaluated using the following tests: trypan blue exclusion test, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide], flow cytometry, cytoskeleton organization analysis, cell cycle, mitochondria membrane depolarization, clonogenicity test, DNA fragmentation test and differential protein expression by HPLC-Chip/MS analysis. F4 fraction characterization was made by HPLC-MS. RESULTS: Petiveria alliacea fraction characterized by de-replication was found to alter actin cytoskeleton organization, induce G2 cell cycle arrest and cause apoptotic cell death in a mitochondria independent way. In addition, we found down regulation of cytoskeleton, chaperone, signal transduction proteins, and proteins involved in metabolic pathways. Finally up regulation of proteins involved in translation and intracellular degradation was also observed. CONCLUSION: The results of this study indicate that Petiveria alliacea exerts multiple biological activities in vitro consistent with cytotoxicity. Further studies in animal models are needed but Petiveria alliacea appears to be a good candidate to be used as an antitumor agent.


Assuntos
Antineoplásicos/farmacologia , Phytolaccaceae , Extratos Vegetais/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Actinas/efeitos dos fármacos , Animais , Morte Celular , Linhagem Celular Tumoral , Fase G2/efeitos dos fármacos , Humanos , Dose Letal Mediana , Melanoma/tratamento farmacológico , Camundongos , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/metabolismo , Células Tumorais Cultivadas
11.
Repert. med. cir ; 14(2): 83-87, 2005. graf
Artigo em Espanhol | LILACS, COLNAL | ID: lil-530511

RESUMO

Para el desarrollo de este estudio se contó con la evaluación preliminar de los conocimientos de un grupo de 20 madrescuyos hijos estuvieron hospitalizados en la unidad de recién nacidos del Hospital de San José durante el segundo semestredel 2003. Los criterios de inclusión fueron: madres cuyos hijos habían superado la fase crítica de la enfermedad, madresde recién nacidos con pesos entre 1.200 y 2.000 g y madres con edades entre 18 y 35 años. Posteriormente, durante el segundosemestre del 2004 se seleccionó un grupo de 20 madres con los mismos criterios de inclusión a quienes se les dictóun programa educativo sobre los cuidados del niño prematuro en casa. Una vez desarrollado el programa se hizo comparaciónentre los dos grupos. El presente estudio es de tipo comparativo transversal entre un grupo intervenido y uno nointervenido y tiene como objetivo evaluar la influencia de un programa educativo sobre los cuidados niño prematuro encasa, aplicando el modelo de autocuidado de Dorothea Orem .La comparación entre los dos grupos se realizó aplicando una prueba de diferencia de proporciones con un nivel de significanciadel 0.05. Los resultados obtenidos confirmaron la hipótesis planteada, por lo que se considera que el programaeducativo fue para el grupo de madres significativo en cuanto a la obtención de conocimientos.


Assuntos
Feminino , Nascimento Prematuro , Recém-Nascido/crescimento & desenvolvimento , Autocuidado , Cuidado do Lactente
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