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1.
Chemosphere ; 349: 140820, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38040253

RESUMO

Microwave-induced plasmas generated at atmospheric pressure are very attractive for a great variety of applications since they have a relatively high electron density and can generate large amounts of reactive species. Argon plasmas can be sustained inside dielectric tubes but are radially contracted and exhibit filamentation effects when the diameter of the tube is not narrow enough (over 1.5 mm). In this work, we describe a new approach for creating microwave (2.45 GHz) plasmas under atmospheric pressure conditions by using a surfatron device and power from 10 W. This modified design of the reactor enables the sustenance of non-filamented argon plasmas. These new plasmas have a higher gas temperature and electron density than the plasma generated in the original surfatron configuration. The new design also allows for the maintenance of plasmas with relatively high proportions of water, resulting in the generation of larger quantities of excited hydroxyl radicals (·OH*). Thus, this novel configuration extends the applicability of microwave-induced plasmas by enabling operation under new conditions. Finally, the degradation of methylene blue (MB) in aqueous solutions has been assessed under different initial dye concentrations and argon flow conditions. The new plasma produces a substantial increase in hydrogen peroxide and nitrate concentrations in water and leads to a noteworthy enhancement in MB degradation efficiency. The introduction of water into the plasma produces a minor additional improvement.


Assuntos
Azul de Metileno , Micro-Ondas , Água , Argônio , Peróxido de Hidrogênio
3.
Sci Rep ; 13(1): 14481, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660209

RESUMO

Exercise plays an important role in cardiac health and enhances the transport of glucose in cardiac muscle by increasing the glucose transporter-4 (GLUT4) content at the cell membrane. The GLUT4 gene is a target of myocyte enhancer transcription factor 2A (MEF2A). Several transcription factors are regulated by microRNAs (miRs), small non-coding RNAs that control gene expression at the posttranscriptional level. In this study we tested the hypothesis that exercise regulates the expression of miR-223 and that MEF2A is a direct target of miR-223. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blot experiments showed that GLUT4 gene expression and protein abundance increased by 30 and 23%, respectively, in the microsomal fraction immediately after exercise, and had returned to control levels after 18 h. In contrast, the increase in GLUT4 in the membrane fraction was delayed. Exercise also increased the protein abundance of transcription factors involved in GLUT4 expression. Immediately after exercise, the protein abundance of MEF2A, nuclear respiratory factor 1 (NRF1), and forkhead box O1 (FOXO1) increased by 18, 30, and 40%, respectively. qRT-PCR experiments showed that miR-223-3p and miR-223-5p expression decreased immediately after exercise by 60 and 30%, respectively, and luciferase assays indicated that MEF2A is a target of the 5p strand of miR-223. Overexpression of miR-223-5p in H9c2 cells decreased the protein abundance of MEF2A. Our results suggest that the exercise-induced increase in GLUT4 content in cardiac muscle is partly due to the posttranscriptional increase in MEF2A protein abundance caused by the decrease in miR-223-5p expression. The exercise-induced decrease in miR-223-3p expression likely contributes to the increases in NRF1 and FOXO1 abundance and GLUT4 content.


Assuntos
MicroRNAs , Miocárdio , Animais , Ratos , Coração , Bioensaio , Fatores de Transcrição MEF2/genética , MicroRNAs/genética , Fator 1 Nuclear Respiratório
4.
Neurologist ; 27(1): 27-29, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34842572

RESUMO

INTRODUCTION: Myelopathy is a common condition with a variety of causes, often eluding diagnosis for some time. Prolonged flexion after surgical procedures has been described. CASE REPORT: A 20-year-old female presented with acute paraparesis after polysubstance drug intoxication and a period of prolonged neck flexion while unconscious. Imaging demonstrated extensive cervicothoracic central cord signal change, in addition to posterior neck musculature hyperintensity. Additional workup directed to other causes was negative. The patient was diagnosed with flexion myelopathy and was treated with a course of steroids, with marked improvement. CONCLUSIONS: The clinician should consider the possibility of flexion-related myelopathy particularly in cases of drug intoxication or prolonged unconsciousness. Signal change within cervical musculature may provide additional clues and allow diagnosis in a timely manner.


Assuntos
Preparações Farmacêuticas , Doenças da Medula Espinal , Adulto , Vértebras Cervicais , Feminino , Humanos , Imageamento por Ressonância Magnética , Amplitude de Movimento Articular , Doenças da Medula Espinal/induzido quimicamente , Doenças da Medula Espinal/diagnóstico por imagem , Adulto Jovem
5.
Sci Rep ; 11(1): 16746, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408194

RESUMO

Several research efforts on cocoa have been focused on parameters for controlling the transformation process to guarantee homogeneity and quality of cocoa beans, the main raw material in the chocolate industry. The main changes that determine the final quality of cocoa-and also the product's homogeneity-occur during fermentation, given the great number of factors that affect the process. This research seeks to identify the most relevant factors affecting quality in order to offer higher-quality and more homogeneous cocoa for the chocolate industry. The dynamics of the fermentation process were observed in three contrasting locations, monitoring different variables and evaluating the final quality of the cocoa. Results show that temperature and pH profile are the key factors to be monitored and controlled in order to achieve high-quality cocoa beans.

6.
Medicina (B Aires) ; 81(4): 536-545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34453794

RESUMO

Individuals with malignancies and COVID-19 have a lower survival compared with the general population. However, the information about the impact of COVID-19 on the whole hematological population is scarce. We aimed to describe the 30th day overall survival (OS) after COVID-19 infection in patients with a hematological disease in Argentina. A completely anonymous survey from the Argentine Society of Hematology was delivered to all the hematologists in Argentina; it started in April 2020. A cut-off to analyze the data was performed in December 2020 and, finally, 419 patients were reported and suitable for the analysis (average age: 58 years, 90% with malignant diseases). After the COVID-19 diagnosis, the 30-day OS for the whole population was 80.2%. From the entire group (419), 101 (24.1%) individuals required intensive care unit admission, where the 30-day OS was 46.6%. Among allogeneic stem cell transplant recipients, the 30-day OS was 70.3%. Factors associated with a low OS were two or more comorbidities, an active hematological disease and history of chemotherapy. In individuals with the three factors, the 30-day OS was 49.6% while the 30-day OS in those without those factors was 100%. Patients with hematological diseases have a higher mortality than the general population. This group represents a challenge and requires careful decision-making of the treatment in order not to compromise the chances of cure.


El presente estudio tuvo por objetivo primario conocer la mortalidad de pacientes con enfermedad hematológica que presentaron infección por COVID-19 en Argentina. Para ello se difundió una encuesta desde la Sociedad Argentina de Hematología (SAH) entre los hematológos para informar sobre los pacientes con enfermedades hematológicas y diagnóstico de infección por SARS- CoV-2, entre el 19/4/2020, y el 7/12/2020. Se incluyeron individuos de todas las edades con diagnóstico de enfermedad hematológica benigna o maligna e infección por SARS-CoV-2 confirmada por técnica de RTPCR. Se analizaron 419 pacientes (mediana 58 años; 90% enfermedades malignas). La supervivencia al día 30 fue de 80.2%. La supervivencia fue menor en aquellos que requirieron internación (74.2%), cuidados intensivos (46.6%) y asistencia respiratoria mecánica (36.8%). Entre los trasplantados alogénicos la supervivencia fue 70.3%. Los factores vinculados a la supervivencia global fueron las comorbilidades, el estado de la enfermedad al momento de la infección y el antecedente de quimioterapia. Se pudo establecer un score en el que aquellos que tuvieron un puntaje de 4 alcanzaron una supervivencia del 49.6% al día 30, mientras que la de los pacientes con score 0 fue del 100% a 30 días. En comparación con la población general, los pacientes con enfermedades hematológicas presentan una mayor mortalidad vinculada al COVID-19, motivo por el cual es primordial definir pautas destinadas a disminuir la exposición de los mismos sin comprometer las posibilidades de beneficiarse del tratamiento de la enfermedad de base.


Assuntos
COVID-19 , Hematologia , Argentina/epidemiologia , Teste para COVID-19 , Humanos , Pessoa de Meia-Idade , SARS-CoV-2
7.
Medicina (B.Aires) ; 81(4): 536-545, ago. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1346504

RESUMO

Abstract Individuals with malignancies and COVID-19 have a lower survival compared with the general population. However, the information about the impact of COVID-19 on the whole hematological population is scarce. We aimed to describe the 30th day overall survival (OS) after COVID-19 infection in pa tients with a hematological disease in Argentina. A completely anonymous survey from the Argentine Society of Hematology was delivered to all the hematologists in Argentina; it started in April 2020. A cut-off to analyze the data was performed in December 2020 and, finally, 419 patients were reported and suitable for the analysis (average age: 58 years, 90% with malignant diseases). After the COVID-19 diagnosis, the 30-day OS for the whole population was 80.2%. From the entire group (419), 101 (24.1%) individuals required intensive care unit admission, where the 30-day OS was 46.6%. Among allogeneic stem cell transplant recipients, the 30-day OS was 70.3%. Factors associated with a low OS were two or more comorbidities, an active hematological disease and history of chemotherapy. In individuals with the three factors, the 30-day OS was 49.6% while the 30-day OS in those without those factors was 100%. Patients with hematological diseases have a higher mortality than the general population. This group represents a challenge and requires careful decision-making of the treatment in order not to compromise the chances of cure.


Resumen El presente estudio tuvo por objetivo primario conocer la mortalidad de pacientes con enfermedad hematológica que presentaron infección por COVID-19 en Argentina. Para ello se difundió una encuesta desde la Sociedad Argentina de Hematología (SAH) entre los hematológos para informar sobre los pacientes con enfermedades hematológicas y diagnóstico de infección por SARS- CoV-2, entre el 19/4/2020, y el 7/12/2020. Se incluyeron individuos de todas las edades con diagnóstico de enfermedad hematológica benigna o maligna e infección por SARS-CoV-2 confirmada por técnica de RT-PCR. Se analizaron 419 pacientes (mediana 58 años; 90% enfermedades malignas). La supervivencia al día 30 fue de 80.2%. La supervivencia fue menor en aquellos que requirieron internación (74.2%), cuidados intensivos (46.6%) y asistencia respiratoria mecánica (36.8%). Entre los trasplantados alogénicos la supervivencia fue 70.3%. Los factores vinculados a la supervivencia global fueron las comorbilidades, el estado de la enfermedad al momento de la infección y el antecedente de quimioterapia. Se pudo establecer un score en el que aquellos que tuvieron un puntaje de 4 alcanzaron una supervivencia del 49.6% al día 30, mientras que la de los pacientes con score 0 fue del 100% a 30 días. En comparación con la población general, los pacientes con enfermedades hematológicas presentan una mayor mortalidad vinculada al COVID-19, motivo por el cual es primordial definir pautas destinadas a disminuir la exposición de los mismos sin comprometer las posibilidades de beneficiarse del tratamiento de la enfermedad de base.


Assuntos
Humanos , Pessoa de Meia-Idade , COVID-19 , Hematologia , Argentina/epidemiologia , Teste para COVID-19 , SARS-CoV-2
8.
Neurochem Int ; 149: 105136, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34274381

RESUMO

Glioblastoma remains one of the most challenging and devastating cancers, with only a very small proportion of patients achieving 5-year survival. The current standard of care consists of surgery, followed by radiation therapy with concurrent and maintenance chemotherapy with the alkylating agent temozolomide. To date, this drug is the only one that provides a significant survival benefit, albeit modest, as patients end up acquiring resistance to this drug. As a result, tumor progression and recurrence inevitably occur, leading to death. Several factors have been proposed to explain this resistance, including an upregulated antioxidant system to keep the elevated intracellular ROS levels, a hallmark of cancer cells, under control. In this review, we discuss the mechanisms of chemoresistance -including the important role of glioblastoma stem cells-with emphasis on antioxidant defenses and how agents that impair redox balance (i.e.: sulfasalazine, erastin, CB-839, withaferin, resveratrol, curcumin, chloroquine, and hydroxychloroquine) might be advantageous in combined therapies against this type of cancer.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Antioxidantes/metabolismo , Neoplasias Encefálicas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/metabolismo , Temozolomida/uso terapêutico , Animais , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/fisiologia , Glioblastoma/tratamento farmacológico , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Temozolomida/farmacologia
9.
J Biomed Sci ; 28(1): 14, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33610185

RESUMO

BACKGROUND: Glutaminase isoenzymes GLS and GLS2 play apparently opposing roles in cancer: GLS acts as an oncoprotein, while GLS2 (GAB isoform) has context specific tumour suppressive activity. Some microRNAs (miRNAs) have been implicated in progression of tumours, including gliomas. The aim was to investigate the effect of GLS and GAB expression on both miRNAs and oxidative status in glioblastoma cells. METHODS: Microarray profiling of miRNA was performed in GLS-silenced LN229 and GAB-transfected T98G human glioblastoma cells and their wild-type counterparts. Results were validated by real-time quantitative RT-PCR. Oxidative status and antioxidant enzymes were determined by spectrophotometric or fluorescence assays in GLS-silenced LN229 and T98G, and GAB-transfected LN229 and T98G. RESULTS: MiRNA-146a-5p, miRNA-140-3p, miRNA-21-5p, miRNA-1260a, and miRNA-92a-3p were downregulated, and miRNA-1246 was upregulated when GLS was knocked down. MiRNA-140-3p, miRNA-1246, miRNA-1260a, miRNA-21-5p, and miRNA-146a-5p were upregulated when GAB was overexpressed. Oxidative status (lipid peroxidation, protein carbonylation, total antioxidant capacity, and glutathione levels), as well as antioxidant enzymes (catalase, superoxide dismutase, and glutathione reductase) of silenced GLS glioblastoma cells and overexpressed GAB glioblastoma cells significantly changed versus their respective control glioblastoma cells. MiRNA-1246, miRNA-1260a, miRNA-146a-5p, and miRNA-21-5p have been characterized as strong biomarkers of glioblastoma proliferation linked to both GLS silencing and GAB overexpression. Total glutathione is a reliable biomarker of glioblastoma oxidative status steadily associated to both GLS silencing and GAB overexpression. CONCLUSIONS: Glutaminase isoenzymes are related to the expression of some miRNAs and may contribute to either tumour progression or suppression through certain miRNA-mediated pathways, proving to be a key tool to switch cancer proliferation and redox status leading to a less malignant phenotype. Accordingly, GLS and GAB expression are especially involved in glutathione-dependent antioxidant defence.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glutaminase/genética , MicroRNAs/metabolismo , Estresse Oxidativo , Linhagem Celular Tumoral , Regulação para Baixo , Glutaminase/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Regulação para Cima
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