RESUMO
Com os avanços tecnológicos e o aprimoramento da prática médica via ultrassonografia, já é possível detectar possíveis problemas no feto desde a gestação. O objetivo deste estudo foi analisar a prática do psicólogo no contexto de gestações que envolvem riscos fetais. Trata-se de um estudo qualitativo sob formato de relato de experiência como psicólogo residente no Serviço de Medicina Fetal da Maternidade Escola da Universidade Federal do Rio de Janeiro (UFRJ). Os registros, feitos por observação participante e diário de campo, foram analisados em dois eixos temáticos: 1) intervenções psicológicas no trabalho em equipe em consulta de pré-natal, exame de ultrassonografia e procedimento de amniocentese; e 2) intervenções psicológicas em casos de bebês incompatíveis com a vida. Os resultados indicaram que o psicólogo nesse serviço é essencial para atuar de forma multiprofissional na assistência pré-natal para gravidezes de alto risco fetal. Ademais, a preceptoria do residente é relevante para sua formação e treinamento para atuação profissional no campo da psicologia perinatal.(AU)
Face to the technological advances and the improvement of medical practice via ultrasound, it is already possible to detect possible problems in the fetus since pregnancy. The objective of this study was to analyze the psychologist's practice in the context of pregnancies which involve fetal risks. It is a qualitative study based on an experience report as a psychologist trainee at the Fetal Medicine Service of the Maternity School of UFRJ. The records, based on the participant observation and field diary, were analyzed in two thematic axes: 1) psychological interventions in the teamwork in the prenatal attendance, ultrasound examination and amniocentesis procedure; and 2) psychological interventions in cases of babies incompatible to the life. The results indicated that the psychologist in this service is essential to work in a multidisciplinary way at the prenatal care for high fetal risk pregnancies. Furthermore, the resident's preceptorship is relevant to their education and training for professional performance in the field of Perinatal Psychology.(AU)
Con los avances tecnológicos y la mejora de la práctica médica a través de la ecografía, ya se puede detectar posibles problemas en el feto desde el embarazo. El objetivo de este estudio fue analizar la práctica del psicólogo en el contexto de embarazos de riesgos fetal. Es un estudio cualitativo basado en un relato de experiencia como residente de psicología en el Servicio de Medicina Fetal de la Escuela de Maternidad de la Universidade Federal do Rio de Janeiro (UFRJ). Los registros, realizados en la observación participante y el diario de campo, se analizaron en dos ejes temáticos: 1) intervenciones psicológicas en el trabajo en equipo, en la consulta prenatal, ecografía y los procedimientos de amniocentesis; y 2) intervenciones psicológicas en casos de bebés incompatibles con la vida. Los resultados señalaron como fundamental la presencia del psicólogo en este servicio trabajando de forma multidisciplinar en la atención prenatal en el contexto de embarazos de alto riesgo fetal. Además, la tutela del residente es relevante para su educación y formación para el desempeño profesional en el campo de la Psicología Perinatal.(AU)
Assuntos
Humanos , Feminino , Gravidez , Cuidado Pré-Natal , Gravidez de Alto Risco , Intervenção Psicossocial , Cardiopatias Congênitas , Ansiedade , Orientação , Dor , Relações Pais-Filho , Pais , Paternidade , Equipe de Assistência ao Paciente , Pacientes , Pediatria , Placenta , Placentação , Complicações na Gravidez , Manutenção da Gravidez , Prognóstico , Teoria Psicanalítica , Psicologia , Transtornos Puerperais , Qualidade de Vida , Radiação , Religião , Reprodução , Fenômenos Fisiológicos Reprodutivos e Urinários , Cirurgia Geral , Síndrome , Anormalidades Congênitas , Temperança , Terapêutica , Sistema Urogenital , Bioética , Consultórios Médicos , Recém-Nascido Prematuro , Trabalho de Parto , Gravidez , Prenhez , Resultado da Gravidez , Adaptação Psicológica , Preparações Farmacêuticas , Ecocardiografia , Espectroscopia de Ressonância Magnética , Família , Aborto Espontâneo , Educação Infantil , Proteção da Criança , Saúde Mental , Saúde da Família , Taxa de Sobrevida , Expectativa de Vida , Causas de Morte , Ultrassonografia Pré-Natal , Mapeamento Cromossômico , Licença Parental , Competência Mental , Rim Policístico Autossômico Recessivo , Síndrome de Down , Assistência Perinatal , Assistência Integral à Saúde , Compostos Químicos , Depressão Pós-Parto , Manifestações Neurocomportamentais , Crianças com Deficiência , Técnicas e Procedimentos Diagnósticos , Número de Gestações , Intervenção em Crise , Afeto , Análise Citogenética , Espiritualidade , Cumplicidade , Valor da Vida , Parto Humanizado , Morte , Tomada de Decisões , Mecanismos de Defesa , Ameaça de Aborto , Atenção à Saúde , Demência , Incerteza , Organogênese , Pesquisa Qualitativa , Gestantes , Diagnóstico Precoce , Nascimento Prematuro , Medição da Translucência Nucal , Mortalidade da Criança , Depressão , Transtorno Depressivo , Período Pós-Parto , Diagnóstico , Técnicas de Diagnóstico Obstétrico e Ginecológico , Etanol , Ego , Emoções , Empatia , Meio Ambiente , Humanização da Assistência , Acolhimento , Ética Profissional , Forma do Núcleo Celular , Nutrição da Gestante , Medida do Comprimento Cervical , Conflito Familiar , Terapia Familiar , Resiliência Psicológica , Fenômenos Reprodutivos Fisiológicos , Doenças Urogenitais Femininas e Complicações na Gravidez , Saco Gestacional , Evento Inexplicável Breve Resolvido , Morte Fetal , Desenvolvimento Embrionário e Fetal , Imagem Multimodal , Mortalidade Prematura , Tomada de Decisão Clínica , Medicina de Emergência Pediátrica , Criança Acolhida , Liberdade , Esgotamento Psicológico , Entorno do Parto , Frustração , Tristeza , Respeito , Angústia Psicológica , Genética , Bem-Estar Psicológico , Obstetra , Culpa , Felicidade , Ocupações em Saúde , Hospitalização , Maternidades , Hospitais Universitários , Desenvolvimento Humano , Direitos Humanos , Imaginação , Infecções , Infertilidade , Anencefalia , Jurisprudência , Complicações do Trabalho de Parto , Licenciamento , Acontecimentos que Mudam a Vida , Cuidados para Prolongar a Vida , Solidão , Amor , Corpo Clínico Hospitalar , Deficiência Intelectual , Princípios Morais , Mães , Narcisismo , Doenças e Anormalidades Congênitas, Hereditárias e Neonatais , Neonatologia , Malformações do Sistema Nervoso , Apego ao ObjetoRESUMO
The effect of combined stresses, photoinhibition, and nutrient depletion on the oxidative stress of cyanobacteria was measured in laboratory experiments to develop the biomass prediction model. Phormidium ambiguum was exposed to various photosynthetically active radiation (PAR) intensities and phosphorous (P) concentrations with fixed nitrogen concentrations. The samples were subjected to stress assays by detecting the hydrogen peroxide (H2O2) concentration and antioxidant activities of catalase (CAT) and superoxide dismutase (SOD). H2O2 concentrations decreased to 30 µmol m-2 s-1 of PAR, then increased with higher PAR intensities. Regarding P concentrations, H2O2 concentrations (nmol L-1) generally decreased with increasing P concentrations. SOD and CAT activities were proportionate to the H2O2 protein-1. No H2O2 concentrations detected outside cells indicated the biological production of H2O2, and the accumulated H2O2 concentration inside cells was parameterized with H2O2 concentration protein-1. With over 30 µmol m-2 s-1 of PAR, H2O2 concentration protein-1 had a similar increasing trend with PAR intensity, independently of P concentration. Meanwhile, with increasing P concentration, H2O2 protein-1 decreased in a similar pattern regardless of PAR intensity. Protein content decreased with gradually increasing H2O2 up to 4 nmol H2O2 mg-1 protein, which provides a threshold to restrict the growth of cyanobacteria. With these results, an empirical formula-protein (mg L-1) = - 192*Log((H2O2/protein)/4.1), where H2O2/protein (nmol mg-1) = - 0.312*PAR2/(502 + PAR2)*((25/PAR)4 + 1)*Log(P/133,100), as a function of total phosphorus concentration, P (µg L-1)-was developed to obtain the cyanobacteria biomass.
Assuntos
Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Catalase/metabolismo , Eutrofização/efeitos da radiação , Peróxido de Hidrogênio/análise , Estresse Oxidativo/efeitos da radiação , Phormidium/metabolismo , Phormidium/efeitos da radiação , Fósforo/metabolismo , Fotossíntese , Radiação , Superóxido Dismutase/metabolismoRESUMO
Decreasing energy consumption is critical to sustainable development. Because temperature regulation for human comfort consumes vast amounts of energy, substantial research efforts are currently directed towards developing passive personal thermal management techniques that cool the human body without any energy consumption1-9. Although various cooling textile designs have been proposed previously, textile-based daytime radiative cooling to a temperature below ambient has not been realized6-13. Silk, a natural protein fabric produced by moth caterpillars, is famous for its shimmering appearance and its cooling and comforting sensation on skin14-17. It has been recently recognized that silk, with its optical properties derived from its hierarchical microstructure, may represent a promising starting point for exploring daytime radiative cooling18-21. However, the intrinsic absorption of protein in the ultraviolet region prevents natural silk from achieving net cooling under sunlight. Here we explore the nanoprocessing of silk through a molecular bonding design and scalable coupling reagent-assisted dip-coating method, and demonstrate that nanoprocessed silk can achieve subambient daytime radiative cooling. Under direct sunlight (peak solar irradiance >900 W m-2) we observed a temperature of ~3.5 °C below ambient (for an ambient temperature of ~35 °C) for stand-alone nanoprocessed silks. We also observed a temperature reduction of 8 °C for a simulated skin when coated with nanoprocessed silk, compared with natural silk. This subambient daytime radiative cooling of nanoprocessed silk was achieved without compromising its wearability and comfort. This strategy of tailoring natural fabrics through scalable nanoprocessing techniques opens up new pathways to realizing thermoregulatory materials and provides an innovative way to sustainable energy.
Assuntos
Temperatura Baixa , Nanotecnologia , Radiação , Seda/química , Têxteis , Óxido de Alumínio/química , Animais , Bombyx , Simulação por ComputadorRESUMO
RESUMEN Objetivos: Evaluar la actividad fotoprotectora de una crema con extracto acuoso liofilizado de maca (ELM) frente a la irradiación ultravioleta (UV) en la piel de ratones. Materiales y métodos: Se realizó un estudio experimental en 35ratones BALB/c. Los tratamientos fueron aplicados por vía tópica en el dorso de los animales y posteriormente irradiados con rayos ultravioleta B, para luego medir el grosor en micras (µm) de muestras histológicas de la piel de los ratones. Se asignaron siete grupos divididos en no irradiado: blanco (G1) e irradiados con luz UV: sin tratamiento (G2); con protector solar comercial con factor de protección solar (FPS) 30 (G3); crema (placebo) (G4); ELM al 15% en agua (G5); ELM al 5% en crema (G6); y ELM al 15% en crema (G7). Se determinó el FPS in vitro, mediante el método de Mansur. Se realizaron las lecturas de las absorbancias en un espectrofotómetro ultravioleta-visible (UV-VIS) y se determinaron los FPS para las siguientes formulaciones: ELM al 5% en crema, benzofenona-4 (BZF-4) y bloqueador solar comercial FPS 30. Resultados: El grosor de piel de ratón en micras (µm) fue de 27,28 en G2; 18,31 en G3; 27,33 en G4; 19,51 en G5 y 18,04 en G6; no hubo diferencia significativa entre el grupo no expuesto a la radiación (G1) y el grupo ELM al 15% en crema (G7), ambos presentaron los menores grosores (12,76 y 14,20 µm, respectivamente). El FPS de ELM al 15% en crema fue 5,480 ± 0,020. Conclusiones: La formulación con ELM en crema presentó actividad fotoprotectora frente a la irradiación UV, los alcaloides fueron los componentes fitoquímicos mayormente encontrados y la formulación fue compatible con el activo (ELM).
ABSTRACT Objectives: To evaluate the photoprotective activity of a cream with lyophilized aqueous extract of maca (LEM) against ultraviolet (UV) irradiation in the skin of mice. Materials and methods: An experimental study was carried out on 35 BALB/c mice. Treatment was applied topically on the dorsum of the animals, which were subsequently irradiated with ultraviolet B rays, and then we measured the thickness in microns (μm) of histological samples of the skin of the mice. Seven groups were assigned, divided into non-irradiated: Blank (G1) and irradiated with UV light: no treatment (G2); with commercial sunscreen with sun protection factor (SPF) 30 (G3); cream (placebo) (G4); LEM at 15% in water (G5); LEM cream at 5% (G6); and LEM cream at 15% (G7). In vitro SPF was determined using the Mansur method. Absorbance readings were taken in an ultraviolet- visible spectrophotometer (UV-VIS) and SPFs were determined for the following formulations: LEM cream at 5%, benzophenone-4 (BZF-4) and commercial sunscreen SPF 30. Results: Mouse skin thickness in microns (μm) was 27.28 in G2; 18.31 in G3; 27.33 in G4; 19.51 in G5 and 18.04 in G6. There was no significant difference between the group not exposed to radiation (G1) and the 15% LEM cream group (G7), both had the lowest thicknesses (12.76 and 14.20 μm, respectively). The SPF of LEM cream at 15% was 5.480 ± 0.020. Conclusions: The formulation with LEM cream showed photoprotective activity against UV irradiation, alkaloids were the phytochemical components mostly found and the formulation was compatible with the active principle (LEM).
Assuntos
Animais , Camundongos , Pele , Raios Ultravioleta , Lepidium , Fator de Proteção Solar , Radiação , Efeitos da Radiação , Protetores Solares , FitoterapiaRESUMO
BACKGROUND: Testicular germ cell tumor (TGCT) incidence has increased in recent decades along with the use and dose of diagnostic radiation. Here we examine the association between reported exposure to diagnostic radiation and TGCT risk. METHODS: We conducted a case-control study of men with and without TGCT recruited from hospital- and population-based settings. Participants reported on exposures to 1) x-ray or CT below the waist and 2) lower GI series or barium enema, which consists of a series of x-rays of the colon. We also derived a combined measure of exposure. We used logistic regression to determine the risk of developing TGCT according to categories of exposures (0, 1-2, or ≥3 exposures) and age at first exposure, adjusting for age, year of birth, race, county, body mass index at diagnosis, family history of TGCT, and personal history of cryptorchidism. RESULTS: There were 315 men with TGCT and 931 men without TGCT in our study. Compared to no exposures, risk of TGCT was significantly elevated among those reporting at least three exposures to x-ray or CT (OR≥3 exposures, 1.78; 95% CI, 1.15-2.76; p = 0.010), lower GI series or barium enema (OR≥3 exposures, 4.58; 95% CI, 2.39-8.76; p<0.001), and the combined exposure variable (OR≥3 exposures, 1.59; 95% CI, 1.05-2.42; p = 0.029). The risk of TGCT was elevated for those exposed to diagnostic radiation at age 0-10 years, compared to those first exposed at age 18 years or later, although this association did not reach statistical significance (OR, 2.00; 95% CI, 0.91-4.42; p = 0.086). CONCLUSIONS: Exposure to diagnostic radiation below the waist may increase TGCT risk. If these results are validated, efforts to reduce diagnostic radiation doses to the testes should be prioritized.
Assuntos
Cavidade Abdominal/efeitos da radiação , Diagnóstico por Imagem/efeitos adversos , Neoplasias Embrionárias de Células Germinativas/etiologia , Pelve/efeitos da radiação , Lesões por Radiação/etiologia , Neoplasias Testiculares/etiologia , Adolescente , Adulto , Fatores Etários , Estudos de Casos e Controles , Criança , Pré-Escolar , Criptorquidismo/etiologia , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Radiação , Fatores de Risco , Testículo/efeitos da radiação , Adulto JovemRESUMO
Radiation dose is important in radiotherapy. Too little, and the treatment is not effective, too much causes radiation toxicity. A biochemical measurement of the effect of radiotherapy would be useful in personalisation of this treatment. This study evaluated changes in exhaled breath volatile organic compounds (VOC) associated with radiotherapy with thermal desorption gas chromatography mass-spectrometry followed by data processing and multivariate statistical analysis. Further the feasibility of adopting gas chromatography ion mobility spectrometry for radiotherapy point-of-care breath was assessed. A total of 62 participants provided 240 end-tidal 1 dm3 breath samples before radiotherapy and at 1, 3, and 6 h post-exposure, that were analysed by thermal-desorption/gas-chromatography/quadrupole mass-spectrometry. Data were registered by retention-index and mass-spectra before multivariate statistical analyses identified candidate markers. A panel of sulfur containing compounds (thio-VOC) were observed to increase in concentration over the 6 h following irradiation. 3-methylthiophene (80 ng.m-3 to 790 ng.m-3) had the lowest abundance while 2-thiophenecarbaldehyde(380 ng.m-3 to 3.85 µg.m-3) the highest; note, exhaled 2-thiophenecarbaldehyde has not been observed previously. The putative tumour metabolite 2,4-dimethyl-1-heptene concentration reduced by an average of 73% over the same time. Statistical scoring based on the signal intensities thio-VOC and 3-methylthiophene appears to reflect individuals' responses to radiation exposure from radiotherapy. The thio-VOC are hypothesised to derive from glutathione and Maillard-based reactions and these are of interest as they are associated with radio-sensitivity. Further studies with continuous monitoring are needed to define the development of the breath biochemistry response to irradiation and to determine the optimum time to monitor breath for radiotherapy markers. Consequently, a single 0.5 cm3 breath-sample gas chromatography-ion mobility approach was evaluated. The calibrated limit of detection for 3-methylthiophene was 10 µg.m-3 with a lower limit of the detector's response estimated to be 210 fg.s-1; the potential for a point-of-care radiation exposure study exists.
Assuntos
Biomarcadores/análise , Testes Respiratórios/métodos , Radiação , Idoso , Calibragem , Expiração , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Compostos Orgânicos Voláteis/análiseRESUMO
In recent times, magnesium oxide (MgO) nanoparticles are proven to be an excellent antibacterial agent which inhibits the growth of bacteria by generating reactive oxygen species (ROS). Release of ROS by nanoparticles will damage the cell membrane of bacteria and leads to the leakage of bacterial internal components and cell death. However, chemically synthesized MgO nanoparticles may possess toxic functional groups which may inhibit healthy human cells along with bacterial cells. Thus, the aim of the present study is to synthesize MgO nanoparticles using leaf extracts of Amaranthus tricolor and photo-irradiation of visible light as a catalyst, without addition of any chemicals. Optimization was performed using Box-Behnken design (BBD) to obtain the optimum condition required to synthesize smallest nanoparticles. The parameters such as time of reaction, the concentration of precursor, and light intensity have been identified to affect the size of biosynthesized nanoparticles and was optimized. The experiment performed with optimized conditions such as 0.001 M concentration of magnesium acetate as precursor, 5 cm distance of light (intensity), and 15 min of reaction time (light exposure) has led to the formation of 74.6 nm sized MgO nanoparticles. The antibacterial activities of MgO nanoparticles formed via photo-irradiation and conventional biosynthesis approach were investigated and compared. The lethal dosage of E. coli for photo-irradiated and conventional biosynthesis MgO nanoparticles was 0.6 ml and 0.4 ml, respectively. Likewise, the lethal dosage of S. aureus for both biosynthesis approaches was found to be 0.4 ml. The results revealed that the antibacterial activity of MgO nanoparticles from both biosynthesis approaches was similar. Thus, photo-irradiated MgO nanoparticles were beneficial over heat-mediated conventional method due to the reduced synthesis duration.
Assuntos
Amaranthus , Antibacterianos/síntese química , Óxido de Magnésio/síntese química , Nanopartículas/química , Extratos Vegetais/síntese química , Antibacterianos/farmacologia , Antibacterianos/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Humanos , Óxido de Magnésio/farmacologia , Óxido de Magnésio/efeitos da radiação , Nanopartículas/administração & dosagem , Nanopartículas/efeitos da radiação , Extratos Vegetais/farmacologia , Extratos Vegetais/efeitos da radiação , Radiação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologiaRESUMO
Oral mucositis refers to erythematous and ulcerative lesions of oral mucosa during chemo/radiotherapy. Treatment modalities were directed towards reduction in severity of oral mucositis. Zinc plays an important role to retard oxidative processes and is considered as the critical component in wound healing. To compare the efficacy of zinc alone with improvised zinc preparation in reducing the severity of oral mucositis. Improvised zinc was a combination of zinc oxide, amla, tulsi and curcumin at 1% therapeutic concentrations. Seventy-five subjects undergoing chemo/radiotherapy were randomly divided into three groups: Group A (25 subjects) had received topical 5% zinc oxide paste trice daily application after food for entire treatment period, initiated 2 d prior to radiotherapy. Group B (25) received improvised zinc preparations (1%) and instructed to apply same as group A. Group C (25) received standard treatment offered by cancer hospital. All the groups were assessed for oral mucositis using WHO grading system at 7th, 14th, 21st, 28th, 35th day by the oncologist and results were tabulated for statistical analysis. Severity of oral mucositis reduced in zinc and improvised zinc group (p=0.096) when compared with controls with significant p value (0.037). Comparison of improvised zinc preparation (1%) group with only zinc group revealed that severity of overall mucositis though was not significant, was less in improvised zinc group with p value (0.029, 0.013) at 28 and 35 d respectively. Improvised zinc administration during radiation therapy was beneficial in reduction of oral mucositis during cancer treatment.
Assuntos
Mucosa Bucal/efeitos dos fármacos , Neoplasias/radioterapia , Extratos Vegetais/uso terapêutico , Lesões por Radiação/tratamento farmacológico , Estomatite/tratamento farmacológico , Óxido de Zinco/uso terapêutico , Zinco/uso terapêutico , Administração Tópica , Adulto , Idoso , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Curcuma/química , Curcumina/administração & dosagem , Curcumina/farmacologia , Curcumina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Mucosa Bucal/efeitos da radiação , Ocimum sanctum/química , Phyllanthus emblica/química , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Radiação , Lesões por Radiação/etiologia , Radioterapia/efeitos adversos , Estomatite/etiologia , Resultado do Tratamento , Cicatrização , Zinco/administração & dosagem , Zinco/farmacologia , Óxido de Zinco/administração & dosagem , Óxido de Zinco/farmacologiaRESUMO
Photobiomodulation via a combination of different radiations can produce different effects on biological tissues, such as cell proliferation and differentiation, when compared to those produced via a single radiation. The present study aims to conduct a review of the literature addressing the results and applications of photobiomodulation induced by a combination of two or more radiations as well as their possible effects. PubMed was used to search for studies with restrictions on the year (< 50 years old) and language (English), including studies using human and animal models, either under healthy or pathologic conditions. Several studies have been conducted to evaluate the combination of different radiation effects on cells and biological tissues. Positive effects resulting from multiple-wavelength radiations could be attributed to different absorption levels because superficial and deep tissues could absorb different levels of radiations. Multiple-wavelength radiations from devices combining radiations emitted by low power lasers and light-emitting diodes could be a new approach for promoting photobiomodulation-induced beneficial effects.
Assuntos
Terapia com Luz de Baixa Intensidade , Radiação , Absorção de Radiação , Animais , Bactérias/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , HumanosRESUMO
Sorbic acid (2,4-hexadienoic acid; HDA) is commonly used as a probe and quencher for triplet-excited chromophoric dissolved organic matter (3CDOM*), an important transient species in natural waters, yet much remains unknown about its reactivity with 3CDOM* and its triplet energy. To better understand the quenching behavior of HDA, we measured HDA quenching rate constants for various humic substance isolates and whole waters with singlet oxygen (1O2) phosphorescence and determined the triplet energy of HDA. Low-temperature phosphorescence measurements determined the triplet energy of HDA to be 217 kJ mol-1, whereas a complementary method based on triplet quenching kinetics found a triplet energy of 184 ± 7 kJ mol-1. Time-resolved 1O2 phosphorescence measurements yielded different HDA quenching rate constants depending on the fitting method. Using an approach that considered the reactivity of the entire triplet pool produced values of (â¼1-10) × 108 M-1 s-1, while an approach that considered only the reactivity of the high-energy triplets output higher rate constants ((â¼7-30) × 108 M-1 s-1). In addition, the model based on high-energy triplet reactivity found that â¼30-60% of 3CDOM* is not quenched by HDA. Findings from this study provide a more comprehensive view on the use of HDA as a probe for 3CDOM*.
Assuntos
Radiação , Ácido Sórbico , Cinética , Fenômenos Físicos , Oxigênio SingleteRESUMO
BACKGROUND: Heat induced by infrared (IR) radiation from sun exposure increases skin temperature and can lead to thermal and photo-aging. However, little is known about the relationship between heat induced by IR radiation and lipid biosynthesis in human sebocytes. This study investigated the expression of factors involved in lipid biosynthesis in human sebocytes exposed to heat. The effect of Cassia tora extract and chrysophanol, which is widely used as anti-inflammatory agent, on the heat shock effect in sebocytes was then examined. METHODS: For the treatment, cells were maintained in culture medium without FBS (i.e., serum starved) for 6 h and then moved for 30 min to incubators at 37 °C (control), 41 °C, or 44 °C (heat shock). Culture media were replaced with fresh media without FBS. To investigate expression of gene and signaling pathway, we performed western blotting. Lipid levels were assessed by Nile red staining. The cytokine levels were measured by cytokine array and ELISA kit. RESULTS: We found that peroxisome proliferator-activated receptor (PPAR)γ and fatty acid synthase (FAS) were upregulated and the c-Jun N-terminal kinase (JNK)/p38 signaling pathways were activated in human sebocytes following heat exposure. Treatment with Cassia tora seed extract and chrysophanol suppressed this up-regulation of PPARγ and FAS and also suppressed the increase in IL-1ß levels. CONCLUSION: These findings provide evidence that IR radiation can stimulate sebum production; Cassia tora seed extract and chrysophanol can reverse lipid stimulated inflammatory mediation, and may therefore be useful for treating skin disorders such as acne vulgaris.
Assuntos
Antraquinonas/farmacologia , Cassia/química , Lipogênese/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antraquinonas/química , Células Epiteliais/química , Ácido Graxo Sintases/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Temperatura Alta/efeitos adversos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Lipogênese/genética , Lipogênese/efeitos da radiação , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos da radiação , PPAR gama/genética , Extratos Vegetais/química , Radiação , Transdução de Sinais/efeitos dos fármacos , Temperatura Cutânea/efeitos da radiação , Proteínas Quinases p38 Ativadas por Mitógeno/genéticaAssuntos
Radioterapia (Especialidade) , Radiação , Radiocirurgia , Cobertura do Seguro , Políticas , Sugestão , Estados UnidosRESUMO
BACKGROUND: While androgen deprivation therapy (ADT) and radiotherapy (RT) are currently used together to treat locally advanced prostate cancer (PCa), RT might have the adverse effect of increasing the PCa androgen receptor (AR) protein expression, which might then increase the resistance to continued RT. METHODS: We used multiple assays for RT sensitivity, protein and RNA expression of AR and related DDR genes, ROS level, DNA damage/repair level, cell cycle and apoptosis. All statistical comparisons were analyzed with t-test or one-way ANOVA. FINDINGS: We demonstrated that RT induced AR expression in C4-2 and CWR22Rv-1 cells. We found that combining RT and ASC-J9®, but not the antiandrogen, Enzalutamide, could increase radiosensitivity via inducing DNA damage, altering the AR mediated and DNA repair pathways, and activating apoptosis. ASC-J9® had little effects on normal bladder cells. INTERPRETATION: Targeting ionizing radiation (IR)-increased AR with the AR degradation enhancer, ASC-J9®, could increase the radiosensitivity while sparing adjacent normal tissue. Mechanism dissection revealed that ASC-J9®, but not Enzalutamide, treatment could increase radiosensitivity via inducing DNA damage, altering DNA repair pathways, as well as activating the IR-induced apoptosis via suppressing the pATR-CHK1 signals. Importantly, results from preclinical studies using an in vivo mouse model also demonstrated that combining RT with ASC-J9® to target AR led to better therapeutic efficacy to suppress PCa progression.
Assuntos
Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Receptores Androgênicos/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Curcumina/análogos & derivados , Curcumina/farmacologia , Modelos Animais de Doenças , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Neoplasias da Próstata/terapia , Proteólise , Radiação , Radioterapia , Receptores Androgênicos/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
High levels of uranium (U) exist in soil, water, and air in the Southwestern United States due, in part, to waste generated from more than 160,000 abandoned hard rock mines located in this region. As a result, many people living in this region are chronically exposed to U at levels that have been linked to detrimental health outcomes. In an effort to establish a relevant in vivo mouse model for future U immunotoxicity studies, we evaluated the tissue distribution of U in immune organs; blood, bone marrow, spleen, and thymus, as well as femur bones, kidneys, and liver, following a 60-d drinking water exposure to uranyl acetate (UA) in male and female C57BL/6J mice. Following the 60-d exposure, there was low overall tissue retention of U (<0.01%) at both the 5 and the 50 ppm (mg/L) oral concentrations. In both male and female mice, there was limited U accumulation in immune organs. U only accumulated at low concentrations in the blood and bone marrow of male mice (0.6 and 16.8 ng/g, respectively). Consistent with previous reports, the predominant sites of U accumulation were the femur bones (350.1 and 399.0 ng/g, respectively) and kidneys (134.0 and 361.3 ng/g, respectively) of male and female mice. Findings from this study provide critical insights into the distribution and retention of U in lymphoid tissues following chronic drinking water exposure to U. This information will serve as a foundation for immunotoxicological assessments of U, alone and in combination with other metals.
Assuntos
Exposição Ambiental , Tecido Linfoide/efeitos da radiação , Compostos Organometálicos/administração & dosagem , Urânio/toxicidade , Animais , Sangue/efeitos da radiação , Medula Óssea/efeitos da radiação , Camundongos , Radiação , Sudoeste dos Estados Unidos , Baço/efeitos da radiação , Timo/efeitos da radiaçãoRESUMO
Selenium, a trace element with anticancer properties, can reduce harmful toxicities of chemotherapy and radiotherapy without compromising efficacy. However, the dose-response relationship in normal versus malignant human cells is unclear. We evaluated how methylseleninic acid (MSA) modulates the toxicity and efficacy of chemotherapy and radiation on malignant and non-malignant human mononuclear blood cells in vitro. We specifically investigated its effects on endoplasmic reticulum stress induction, intracellular glutathione concentration, DNA damage and viability of peripheral blood mononuclear cells and THP1 monocytic leukaemia cells in response to radiation, cytosine arabinoside or doxorubicin chemotherapy. MSA, at lower concentrations, induced protective responses in normal cells but cytotoxic effects in malignant cells, alone and in conjunction with chemotherapy or radiation. However, in normal cells higher concentrations of MSA were directly toxic and increased the cytotoxicity of radiation but not chemotherapy. In malignant cells higher MSA concentrations were generally more effective in combination with cancer treatments. Thus, optimal MSA concentrations differed between normal and malignant cells and treatments. This work supports clinical reports that selenium can significantly reduce dose-limiting toxicities of anticancer therapies and potentially improve efficacy of anticancer treatments. The optimal selenium compound and dose is not yet determined.
Assuntos
Antineoplásicos/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/efeitos da radiação , Radiação , Selênio/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Interações Medicamentosas , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos da radiação , Glutationa/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Compostos Organosselênicos/farmacologiaRESUMO
Cancer-initiating/sustaining stem cell subsets (CSCs) have the potential to regenerate cancer cell populations and are resistant to routine therapeutic strategies, thus attracting much attention in anticancer research. In this study, an innovative framework of endogenous microenvironment-renewal for addressing such a dilemma has been just developed. CSCs in three-dimensional multipotent spheroid-engineered biologics were prepared with 150 Gy radiation and inoculated into 15-mo-old BALB/c and C57BL/6 mice bearing diverse advanced tumors covering Mammary 4T1, liver Hepa, lung LL/2, and colon C26 tumors and distant metastases. Subsequently, the systematic microenvironment of tumor-bearing hosts was rapidly remodeled to resettle thymic cortex and medulla rudiment as an endogenous foxn1-thymosin reprogramming TCR-repertoire for resetting MHC-unrestricted multifunction renewal. Postrenewal Vγ4γδT-subsets would bind and lead migrating CSCs into apoptosis. Moreover, TCR repertoire multifunction renewal could reverse tumor metastases from tumoricidal resistance into eventual regression as a blockade of cancer-sustaining Bmi-1/Nanog-Oct4-Sox2 renewal loop with sequent multivalent depletion of both migrating/in situ CSCs and non-stem terminal cancer cell subsets. This study represents a promising start to set up a generalizable strategy of three-dimensional biologics evoking an endogenous integral microenvironment into pluripotent renewal versus advanced cancer.
Assuntos
Terapia Biológica , Técnicas de Reprogramação Celular , Células-Tronco Multipotentes/fisiologia , Neoplasias Experimentais/imunologia , Células-Tronco Neoplásicas/fisiologia , Linfócitos T/imunologia , Timo/fisiologia , Animais , Apoptose , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular Tumoral , Autorrenovação Celular , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Imunidade Celular , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Neoplasias Experimentais/terapia , Radiação , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Timosina/genética , Timosina/metabolismo , Engenharia Tecidual , Microambiente TumoralRESUMO
The induction of RIBE (Radiation Induced Bystander Effect) is a non-target effect of low radiation doses that has already been verified at an inter-organismic level in fish and small mammals. Although the theoretical impact in the field of environmental risk assessment (ERA) is possible, there is a gap of knowledge regarding this phenomenon in invertebrate groups and following environmentally relevant exposures. To understand if RIBE should be considered for ERA of radionuclide-rich wastewaters, we exposed Daphnia magna (<24â¯h and 5d old) to a 2% diluted uranium mine effluent for 48â¯h, and to a matching dose of waterborne uranium (55.3⯵gâ¯L-1). Then the exposed organisms were placed (24 and 48â¯h) in a clean medium together with non-exposed neonates. The DNA damage observed for the non-exposed organisms was statistically significant after the 24â¯h cohabitation for both uranium (neonates pâ¯=â¯0.002; 5â¯d-old daphnids pâ¯=â¯<0.001) and uranium mine effluent exposure (only for neonates pâ¯=â¯0.042). After 48â¯h cohabitation significant results were obtained only for uranium exposure (neonates pâ¯=â¯0.017; 5â¯d-old daphnids pâ¯=â¯0.013). Although there may be some variability associated to age and exposure duration, the significant DNA damage detected in non-exposed organisms clearly reveals the occurrence of RIBE in D. magna. The data obtained and here presented are a valuable contribution for the discussion about the relevance of RIBE for environmental risk assessment.
Assuntos
Efeito Espectador/efeitos da radiação , Daphnia/efeitos dos fármacos , Mineração , Mutagênicos/toxicidade , Radiação , Urânio/toxicidade , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade , Animais , Dano ao DNA , Daphnia/efeitos da radiação , Relação Dose-Resposta à Radiação , Exposição AmbientalRESUMO
The thyroid gland is vulnerable not only to external radiation but also to internal radiation, because the thyroid cells can incorporate radioactive iodine when synthesizing thyroid hormones. Since radiation-induction of thyroid neoplasia, including thyroid cancer, is well recognized, the data on radiation-related thyroid autoimmunity and dysfunction are summarized and reviewed. High-dose irradiation, irrespective of being external or internal, is strongly associated with a risk of hypothyroidism (with the prevalence ranging from 2.4% to 31%) and of Graves' hyperthyroidism (with the prevalence being up to 5%). It is easy to understand that high-dose irradiation induces hypothyroidism with some frequency, because high-dose irradiation destroys the thyroid gland. On the other hand, the basis for development of hyperthyroidism is mechanistically unclear, and it is merely speculative that autoantigens may be released from damaged thyroid glands and recognized by the immune system, leading to the development of anti-thyrotropin receptor antibodies and Graves' hyperthyroidism in subjects who are immunologically predisposed to this ailment. In contrast, the data on moderate to low-dose irradiation on thyroid autoimmunity and dysfunction are inconsistent. Although it is difficult to draw a definitive conclusion, some data may suggest a transient effect of moderate- to low-dose irradiation on hypothyroidism and autoimmune thyroiditis, implying that the effect, if it exists, is reversible. Finally, no report has shown a statistically significant increase in the prevalence of moderate- to low-dose irradiation-induced Graves' hyperthyroidism.
Assuntos
Autoimunidade/efeitos da radiação , Radiação , Glândula Tireoide/imunologia , Glândula Tireoide/fisiopatologia , Relação Dose-Resposta à Radiação , Humanos , Glândula Tireoide/efeitos da radiaçãoRESUMO
This work aims to determine the relationship between Cerenkov photon emission and radiation dose from internal radionuclide irradiation. Water and thyroid phantoms were used to simulate the distribution of Cerenkov photon emission and dose deposition through Monte Carlo method. The relationship between Cerenkov photon emission and dose deposition was quantitatively analyzed. A neck phantom was also used to verify Cerenkov photon detection for thyroid radionuclide therapy. Results show that Cerenkov photon emission and dose deposition exhibit the same distribution pattern in water phantom, and this relative distribution relationship also existed in the thyroid phantom. Moreover, Cerenkov photon emission exhibits a specific quantitative relation to dose deposition. For thyroid radionuclide therapy, only a part of Cerenkov photon produced by thyroid could penetrate the body for detection; therefore, the use of Cerenkov radiation for measurement of radionuclide therapy dose may be more suitable for superficial tumors. This study demonstrated that Cerenkov radiation has the potential to be used for measuring radiation dose for radionuclide therapy.
Assuntos
Radiação , Radioisótopos/uso terapêutico , Radiometria , Simulação por Computador , Relação Dose-Resposta à Radiação , Humanos , Imagens de Fantasmas , Fótons , Glândula Tireoide/efeitos da radiação , ÁguaRESUMO
D-penicillamine (DPEN), a copper chelator, has been used in the treatment of Wilson's disease, cystinuria, and rheumatoid arthritis. Recent evidence suggests that DPEN in combination with biologically relevant copper (Cu) concentrations generates H2O2 in cancer cell cultures, but the effects of this on cancer cell responses to ionizing radiation and chemotherapy are unknown. Increased steady-state levels of H2O2 were detected in MB231 breast and H1299 lung cancer cells following treatment with DPEN (100µM) and copper sulfate (15µM). Clonogenic survival demonstrated that DPEN-induced cancer cell toxicity was dependent on Cu and was significantly enhanced by depletion of glutathione [using buthionine sulfoximine (BSO)] as well as inhibition of thioredoxin reductase [using Auranofin (Au)] prior to exposure. Treatment with catalase inhibited DPEN toxicity confirming H2O2 as the toxic species. Furthermore, pretreating cancer cells with iron sucrose enhanced DPEN toxicity while treating with deferoxamine, an Fe chelator that inhibits redox cycling, inhibited DPEN toxicity. Importantly, DPEN also demonstrated selective toxicity in human breast and lung cancer cells, relative to normal untransformed human lung or mammary epithelial cells and enhanced cancer cell killing when combined with ionizing radiation or carboplatin. Consistent with the selective cancer cell toxicity, normal untransformed human lung epithelial cells had significantly lower labile iron pools than lung cancer cells. These results support the hypothesis that DPEN mediates selective cancer cell killing as well as radio-chemo-sensitization by a mechanism involving metal ion catalyzed H2O2-mediated oxidative stress and suggest that DPEN could be repurposed as an adjuvant in conventional cancer therapy.