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1.
J Environ Radioact ; 243: 106811, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35007922

RESUMO

External sources of radiation originate from cosmic rays and natural radioactive elements, principally 40K and decay products in the uranium and thorium decay series occurring in the ground. People are exposed to terrestrial radiation and cosmic rays everywhere and at all times. To assess Canadians' external exposure to natural radiation, five years (2016-2020) of real-time environment monitoring data recorded by Health Canada's Fixed Point Surveillance (FPS) network were analysed for 36 monitoring stations across Canada. Absorbed dose rates in air from terrestrial radiation vary geographically and seasonally. Absorbed dose rates due to cosmic rays depend strongly on the elevation and vary with solar activities. The population-weighted annual outdoor ambient dose equivalent rates are 20 nSv/h for terrestrial radiation and 52 nSv/h for cosmic rays. Considering that, on average, Canadians spend 89% of their time indoors and 11% of the time outdoors, the population-weighted annual effective doses were calculated as 443 µSv (54 µSv outdoors and 389 µSv indoors), with 20.6% (91 µSv) from terrestrial radiation and 79.4% (352 µSv) from cosmic rays.


Assuntos
Radiação Cósmica , Monitoramento de Radiação , Poluentes Radioativos do Solo , Radiação de Fundo , Canadá , Exposição Ambiental/análise , Monitoramento Ambiental , Raios gama , Humanos , Doses de Radiação , Poluentes Radioativos do Solo/análise
2.
Curr Microbiol ; 79(2): 61, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982197

RESUMO

This study investigated the effects of gamma-radiation on Tetrahymena pyriformis. The experimental approach consists of exposing T. pyriformis growing in presence of Cesium-137 (137Cs) at dose rates of 1, 2, 4, and 6 cGy h-1 and Cobalt-60 (60Co) at dose rates of 8, 10, 15, and 20 cGy h-1. The radiation doses effects on growth, morphology, some metabolic enzymes, and reactive oxygen species (ROS) markers have been evaluated. When cells were growing in irradiating conditions at dose rates beyond 4 cGy h-1, a decreasing of cells and generation numbers with a prolongation of generation time and a change of morphological aspect with rounding-off of cells were observed compared to the control. The 50%-inhibitory dose (ID50) for radiation was estimated at 1568.72 ± 158.45 cGy. The gamma-radiation at dose rates more than 6 cGy h-1, affected both glyceraldehyde 3-phosphate dehydrogenase and succinate dehydrogenase by inhibiting their activities. All of these effects were more pronounced when cells were irradiated at the dose rate of 20 cGy h-1 using 60Co source. For ROS markers generated by gamma-radiation in T. pyriformis, the results showed an increase of the lipid peroxidation in cells grown in presence of gamma-radiation at dose rates more than 6 cGy h-1 and an enhancement in catalase and superoxide dismutase activities from the dose rate of 1 cGy h-1. These encouraging results suggested the use of T. pyriformis as a unicellular model cell to investigate other aspects of the response to ionizing radiation.


Assuntos
Tetrahymena pyriformis , Radioisótopos de Césio , Radioisótopos de Cobalto , Relação Dose-Resposta à Radiação , Raios gama
3.
Toxicol Mech Methods ; 32(1): 67-76, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34353221

RESUMO

This study investigates the concerted hepatoprotective effects for three doses of bradykinin potentiating factor (BPF) and/or followed by exposure to a low dose of γ-radiation (LDR) against Naja haje envenoming in rats. Male rats were injected with three consecutive doses of BPF (1 µg/g i.p. for 3 days), followed by exposure to a low dose of gamma radiation (0.5 Gy), and then rats were injected with a dose of Naja haje venom (250 µg/kg i.p.). Results showed that Naja haje causes liver damage, significant elevation of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), cytochrome c, Nitric oxide (NO), malondialdehyde (MDA) and significant depletion in glutathione peroxidase (GPx) contents. In addition, significant depletion in B-cell lymphoma 2 (Bcl-2) and significant elevation in BcL-2 associated X (Bax protein), nuclear factor kappa B (NF-κB), interleukin-1ß (IL-1ß) in hepatocytes. Bradykinin potentiating factor and/or low dose of γ-radiation caused improvement in liver damage caused by Naja haje venom by a significant decrease in ALT, AST, ALP levels, Bax, cytochrome c, NF-κB, IL-1ß, NO and MDA contents, BPF alone or combined with low dose radiation caused a significant increase in Bcl2 and GPx contents. In conclusion, the concerted impact of BPF and LDR may provide an effective venom detoxification tool that helps to reduce hepatic toxicity and extends the lifespan.


Assuntos
Bradicinina , Naja haje , Animais , Bradicinina/metabolismo , Raios gama , Fígado/metabolismo , Masculino , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteína X Associada a bcl-2/metabolismo
4.
Meat Sci ; 184: 108700, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34768181

RESUMO

The current investigation assessed the effect of pectin (PE) biodegradable nanocomposite coating containing curcumin nanoparticles (CNP) and ajowan (Carum copticum) essential oil nanoemulsion (ANE) combined with low-dose gamma irradiation on microbial, physiochemical, and sensorial qualities of lamb loins during refrigeration conditions. Active coating combined with gamma irradiation reduced the count number of mesophilic and psychrotrophic bacteria, lactic acid bacteria, Enterobacteriaceae; and minimized lipid and protein oxidation changes, total volatile basic nitrogen content, met-myoglobin formation, and color deterioration in the loin samples. The increased shelf-life of lamb loins up to 25 days compared with 5 days assigned for the control group can be associated with the application of ionizing radiation and edible PE coating containing CNP and ANE, which might be due to the synergistic or additive effects of treatments. Overall, as an effective preservation technique, a combination of PE + CNP + ANE and irradiation can be recommended for prolonging the shelf-life of lamb loins during refrigerated storage.


Assuntos
Conservação de Alimentos/métodos , Raios gama , Óleos Voláteis , Carne Vermelha/análise , Carne Vermelha/microbiologia , Animais , Carum/química , Curcumina/química , Irradiação de Alimentos/métodos , Microbiologia de Alimentos , Armazenamento de Alimentos/métodos , Nanocompostos , Pectinas/química , Ovinos
5.
Chemosphere ; 287(Pt 2): 132233, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826924

RESUMO

An empirical method was applied to estimate the 222Rn fluxes distribution across the Campania region (Italy) by using both gamma-rays and U, Th, K concentrations in soils. As a first step, K, Th and U soil concentrations and 4 K, 238U and 232Th activity have been converted into their own specific activity to calculate the Terrestrial Gamma Dose Rate (TGDR). This latter has been then used to determine the 222Rn fluxes across the region. Regardless of the radiometric or geochemical origin, 222Rn fluxes reached, as expected, their maximum values in correspondence with the volcanic centres of Campania (Mt. Somma-Vesuvius, Phlegrean Fields, Mt. Roccamonfina). However, comparing the results obtained from the two different datasets, it was also possible to infer the existence of contributions to surficial 222Rn fluxes proceeding from both some underlying geological bodies and active seismogenic sources. In line with some national regulations, the 222Rn flux esteemed from gamma radiations was also used to assess the possible regional distribution of risk deriving from the indoor environmental exposure to 222Rn; results were compared with standardized incidence rates (SIRs) of lung cancer for an area on the south-western sector of Mt. Somma-Vesuvius showing a potential spatial relationship among flux data and SIRs.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Solo , Poluentes Radioativos do Ar/análise , Raios gama , Itália , Radônio/análise , Poluentes Radioativos do Solo/análise
6.
Int J Mol Sci ; 22(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34948098

RESUMO

Space radiation presents a substantial threat to travel beyond Earth. Relatively low doses of high-energy particle radiation cause physiological and behavioral impairments in rodents and may pose risks to human spaceflight. There is evidence that 56Fe irradiation, a significant component of space radiation, may be more harmful to males than to females and worsen Alzheimer's disease pathology in genetically vulnerable models. Yet, research on the long-term, sex- and genotype-specific effects of 56Fe irradiation is lacking. Here, we irradiated 4-month-old male and female, wild-type and Alzheimer's-like APP/PS1 mice with 0, 0.10, or 0.50 Gy of 56Fe ions (1GeV/u). Mice underwent microPET scans before and 7.5 months after irradiation, a battery of behavioral tests at 11 months of age and were sacrificed for pathological and biochemical analyses at 12 months of age. 56Fe irradiation worsened amyloid-beta (Aß) pathology, gliosis, neuroinflammation and spatial memory, but improved motor coordination, in male transgenic mice and worsened fear memory in wild-type males. Although sham-irradiated female APP/PS1 mice had more cerebral Aß and gliosis than sham-irradiated male transgenics, female mice of both genotypes were relatively spared from radiation effects 8 months later. These results provide evidence for sex-specific, long-term CNS effects of space radiation.


Assuntos
Doença de Alzheimer , Comportamento Animal/efeitos da radiação , Raios gama , Genótipo , Radioisótopos de Ferro , Presenilina-1 , Caracteres Sexuais , Memória Espacial/efeitos da radiação , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Presenilina-1/genética , Presenilina-1/metabolismo , Fatores de Tempo
7.
Int J Mol Sci ; 22(24)2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34948147

RESUMO

Intensive adjuvant radiotherapy (RT) is a standard treatment for glioblastoma multiforme (GBM) patients; however, its effect on the normal brain tissue remains unclear. Here, we investigated the short-term effects of multiple irradiation on the cellular and extracellular glycosylated components of normal brain tissue and their functional significance. Triple irradiation (7 Gy*3 days) of C57Bl/6 mouse brain inhibited the viability, proliferation and biosynthetic activity of normal glial cells, resulting in a fast brain-zone-dependent deregulation of the expression of proteoglycans (PGs) (decorin, biglycan, versican, brevican and CD44). Complex time-point-specific (24-72 h) changes in decorin and brevican protein and chondroitin sulfate (CS) and heparan sulfate (HS) content suggested deterioration of the PGs glycosylation in irradiated brain tissue, while the transcriptional activity of HS-biosynthetic system remained unchanged. The primary glial cultures and organotypic slices from triple-irradiated brain tissue were more susceptible to GBM U87 cells' adhesion and proliferation in co-culture systems in vitro and ex vivo. In summary, multiple irradiation affects glycosylated components of normal brain extracellular matrix (ECM) through inhibition of the functional activity of normal glial cells. The changed content and pattern of PGs and GAGs in irradiated brain tissues are accompanied by the increased adhesion and proliferation of GBM cells, suggesting a novel molecular mechanism of negative side-effects of anti-GBM radiotherapy.


Assuntos
Neoplasias Encefálicas , Encéfalo , Proliferação de Células/efeitos da radiação , Raios gama , Glioblastoma , Neoplasias Experimentais , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Adesão Celular/efeitos da radiação , Proteínas da Matriz Extracelular/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/radioterapia , Masculino , Camundongos , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/radioterapia , Proteoglicanas/metabolismo
8.
Appl Microbiol Biotechnol ; 105(23): 8869-8880, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34748037

RESUMO

Huperzine-A (HupA) is an emerging, powerful, and promising natural acetylcholinesterase inhibitor. Despite that, the achieved yields of HupA from microbial sources are still far from the industrial applications. Accordingly, this paper was conducted to valorize solid-state fermentation (SSF) as an efficient production platform of HupA. Four agro-industrial wastes, namely rice bran, potato peel, sugarcane bagasse, and wheat bran, were tested and screened as cultural substrates for the production of HupA by the endophytic Alternaria brassica under SSF. Maximum HupA production was attained on using rice bran moistened by Czapex's dox mineral broth. In the effort to increase the HupA titer, supplementation of the best moistening agent by different carbon and nitrogen sources was successfully investigated. Additionally, factors affecting HupA production under SSF including substrate concentration, moistening level, and inoculum concentration were optimized using response surface methodology. A Box-Behnken design was applied for generating a predictive model of the interactions between these factors. Under the optimum conditions of 15 g rice bran, inoculum concentration of 5 × 106 spores mL-1, and 60% moisture level, HupA concentration was intensified to 518.93 µg g-1. Besides, HupA production by the fungal strain was further enhanced using gamma-irradiation mutagenesis. The final HupA production was significantly intensified following exposure to 0.5 KGy gamma radiation to 1327 µg g-1, which represents a 12.85-fold increase. This is the first report on the successful production of the natural fungal metabolite HupA under SSF. Moreover, the achieved yield in this study using agro-industrial wastes may contribute to reducing the cost of HupA manufacture.Key points• Different agro-industrial by-products were tried as cultural substrates for the production of the acetylcholinesterase inhibitor HupA under SSF for the first time.• Factors affecting HupA production under SSF were optimized using response surface methodology.• The final HupA production was intensified following exposure to gamma radiation recording 1327 µg g-1, which represents a 12.85-fold increase.


Assuntos
Alternaria , Inibidores da Colinesterase , Acetilcolinesterase , Alcaloides , Fermentação , Raios gama , Sesquiterpenos
9.
Sci Rep ; 11(1): 19888, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34615977

RESUMO

To cope with the shortage of filtering facepiece respirators (FFRs) during the coronavirus (COVID-19) pandemic, healthcare institutions were forced to reuse FFRs after applying different decontamination methods including gamma-irradiation (GIR). The aim of this study was to evaluate the effect of GIR on the filtration efficiency (FE) of FFRs and on SARS-CoV-2 detection. The FE of 2 FFRs types (KN95 and N95-3 M masks) was assessed at different particle sizes (0.3-5 µm) following GIR (0-15 kGy) delivered at either typical (1.65 kGy/h) or low (0.5088 kGy/h) dose rates. The detection of two SARS-CoV-2 RNA genes (E and RdRp4) following GIR (0-50 kGy) was carried out using RT-qPCR assay. Both masks showed an overall significant (P < 0.001) reduction in FE with increased GIR doses. No significant differences were observed between GIR dose rates on FE. The GIR exhibited significant increases (P ≤ 0.001) in the cycle threshold values (ΔCt) of both genes, with no detection following high doses. In conclusion, complete degradation of SARS-CoV-2 RNA can be achieved by high GIR (≥ 30 kGy), suggesting its potential use in FFRs decontamination. However, GIR exhibited adverse effects on FE in dose- and particle size-dependent manners, rendering its use to decontaminate FFRs debatable.


Assuntos
COVID-19/virologia , Descontaminação/métodos , Máscaras , SARS-CoV-2/isolamento & purificação , Ventiladores Mecânicos , COVID-19/prevenção & controle , COVID-19/transmissão , Filtração , Raios gama , Humanos , Tamanho da Partícula
10.
Toxicon ; 203: 58-65, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34626598

RESUMO

The goal of this research is to study the mitigating impact of bradykinin potentiating factor (BPF) found in scorpion Androctonus bicolor venom on irradiation-induced lung damage as a new functional target for angiotensin-converting enzyme inhibitors (ACEIs). Male rats were exposed to 7 Gy of γ-radiation as a single dose, with a biweekly intraperitoneal injection of 1 µg/g BPF. Gamma irradiation not only boosted the ACE activity and angiotensin II (Ang II) level, in lung tissue but also significantly depressed the angiotensin (1-7) (Ang (1-7)) that, lead to lung toxicity through a significant elevation of pulmonary levels of CXC-chemokine receptor 4 (CXCR4), toll-like receptor 4 (TLR4), nitric oxide (NO) and lactate dehydrogenase (LDH) activity with a marked disruption in oxidative stress markers, via a reduction in the level of total thiol (tSH) and superoxide dismutase (SOD) activity associated with an elevation in protein carbonyl (PCO) contents. In addition, apoptotic consequences of gamma irradiation were evidenced by raising the levels of mitogen-activated protein kinase (MAPK), C-Jun N-Terminal Kinases (JNK), and cleaved caspase-3. BPF administration leads to ACE inhibition, consequently sustaining decreased Ang II alongside increased Ang (1-7) production. Those sensitive molecules reduce irradiated lung issues. In conclusion, BPF significantly diminished the biochemical and histopathological consequences of radiation through renin-angiotensin system (RAS) control and ACE suppression in the lung.


Assuntos
Bradicinina , Escorpiões , Angiotensina I , Angiotensina II , Inibidores da Enzima Conversora de Angiotensina , Animais , Raios gama , Pulmão , Masculino , Fragmentos de Peptídeos , Peptidil Dipeptidase A , Ratos
11.
Sensors (Basel) ; 21(19)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34640731

RESUMO

The features of the atmospheric γ-background reaction to liquid atmospheric precipitation in the form of bursts is investigated, and various forms of them are analyzed. A method is described for interpreting forms of the measured γ-background response with the determination of the beginning and ending time of precipitation, the distinctive features of changes in the intensity of precipitation and the number of single (separate) events that form one burst. It is revealed that a change in the intensity of precipitation in one event leads to a change in the γ-radiation dose rate increase speed (time derivative). A method of estimating the average value of the intensity and amount of precipitation for one event, reconstructing the intensity spectrum from experimental data on the dynamics of the measured dose rate of γ-radiation, is developed. The method takes into account the radioactive decay of radon daughter products in the atmosphere and on the soil surface during precipitation, as well as the purification of the atmosphere from radionuclides. Recommendations are given for using the developed method to correct for changes (daily variations) in radon flux density from the ground surface, which lead to variations in radon in the atmosphere. Experimental verification of the method shows good agreement between the values of the intensity of liquid atmospheric precipitation, calculated and measured with the help of shuttle and optical rain precipitation gauges.


Assuntos
Poluentes Radioativos do Ar , Radônio , Poluentes Radioativos do Ar/análise , Atmosfera , Raios gama , Chuva
12.
Int J Mol Sci ; 22(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34638618

RESUMO

Wildlife is chronically exposed to various sources of ionizing radiations, both environmental or anthropic, due to nuclear energy use, which can induce several defects in organisms. In invertebrates, reproduction, which directly impacts population dynamics, has been found to be the most radiosensitive endpoint. Understanding the underlying molecular pathways inducing this reproduction decrease can help in predicting the effects at larger scales (i.e., population). In this study, we used a life stage dependent approach in order to better understand the molecular determinants of reproduction decrease in the roundworm C. elegans. Worms were chronically exposed to 50 mGy·h-1 external gamma ionizing radiations throughout different developmental periods (namely embryogenesis, gametogenesis, and full development). Then, in addition to reproduction parameters, we performed a wide analysis of lipids (different class and fatty acid via FAMES), which are both important signaling molecules for reproduction and molecular targets of oxidative stress. Our results showed that reproductive defects are life stage dependent, that lipids are differently misregulated according to the considered exposure (e.g., upon embryogenesis and full development) and do not fully explain radiation induced reproductive defects. Finally, our results enable us to propose a conceptual model of lipid signaling after radiation stress in which both the soma and the germline participate.


Assuntos
Caenorhabditis elegans/efeitos da radiação , Metabolismo dos Lipídeos/efeitos da radiação , Reprodução/efeitos da radiação , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/fisiologia , Ácidos Graxos/metabolismo , Feminino , Raios gama/efeitos adversos , Masculino , Modelos Biológicos , Estresse Oxidativo/efeitos da radiação , Tolerância a Radiação , Reprodução/fisiologia
13.
J Insect Sci ; 21(5)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34718645

RESUMO

Radiation is considered as a promising insect pest control strategy for minimizing postharvest yield losses. Among various techniques, irradiation is a method of choice as it induces lethal biochemical or molecular changes that cause a downstream cascade of abrupt physiological abnormalities at the cellular level. In this study, we evaluated the effect of 60Co-γ radiation on various developmental stages of Zeugodacus cucurbitae Coquillett and subsequent carry-over effects on the progeny. For this purpose, we treated eggs with 30- and 50-Gy radiation doses of 60Co-γ. We found that radiation significantly affected cellular antioxidants, insect morphology, and gene expression profiles. Our results indicate that in response to various doses of irradiation reactive oxygen species, catalase, peroxidase, and superoxide dismutase activities were increased along with a significant increase in the malondialdehyde (MDA) content. We observed higher mortality rates during the pupal stage of the insects that hatched from irradiated eggs (50 Gy). Furthermore, the life span of the adults was reduced in response to 50 Gy radiation. The negative effects carried over to the next generation were marked by significantly lower fecundity in the F1 generation of the irradiation groups as compared to control. The radiation induced morphological abnormalities at the pupal, as well as the adult, stages. Furthermore, variations in the gene expression following irradiation are discussed. Taken together, our results signify the utility of 60Co-γ radiation for fruit fly postharvest management.


Assuntos
Apoptose/efeitos da radiação , Raios gama , Expressão Gênica/efeitos da radiação , Tephritidae/efeitos da radiação , Animais , Antioxidantes/metabolismo , Antioxidantes/efeitos da radiação , Apoptose/genética , Catalase/metabolismo , Catalase/efeitos da radiação , Radioisótopos de Cobalto/farmacologia , Controle de Insetos/métodos , Proteínas de Insetos/metabolismo , Proteínas de Insetos/efeitos da radiação , Larva/genética , Larva/metabolismo , Larva/fisiologia , Larva/efeitos da radiação , Longevidade/efeitos da radiação , Malondialdeído/metabolismo , Malondialdeído/efeitos da radiação , Peroxidase/metabolismo , Peroxidase/efeitos da radiação , Controle de Pragas/métodos , Pupa/genética , Pupa/metabolismo , Pupa/fisiologia , Pupa/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Tephritidae/genética , Tephritidae/metabolismo , Tephritidae/fisiologia
14.
ScientificWorldJournal ; 2021: 9342748, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712107

RESUMO

Background: Recently, an outbreak of a novel human coronavirus SARS-CoV-2 has become a world health concern leading to severe respiratory tract infections in humans. Virus transmission occurs through person-to-person contact, respiratory droplets, and contaminated hands or surfaces. Accordingly, we aim at reviewing the literature on all information available about the persistence of coronaviruses, including human and animal coronaviruses, on inanimate surfaces and inactivation strategies with biocides employed for chemical and physical disinfection. Method: A comprehensive search was systematically conducted in main databases from 1998 to 2020 to identify various viral disinfectants associated with HCoV and methods for control and prevention of this newly emerged virus. Results: The analysis of 62 studies shows that human coronaviruses such as severe acute respiratory syndrome (SARS) coronavirus, Middle East respiratory syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV), canine coronavirus (CCV), transmissible gastroenteritis virus (TGEV), and mouse hepatitis virus (MHV) can be efficiently inactivated by physical and chemical disinfectants at different concentrations (70, 80, 85, and 95%) of 2-propanol (70 and 80%) in less than or equal to 60 s and 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Additionally, glutaraldehyde (0.5-2%), formaldehyde (0.7-1%), and povidone-iodine (0.1-0.75%) could readily inactivate coronaviruses. Moreover, dry heat at 56°C, ultraviolet light dose of 0.2 to 140 J/cm2, and gamma irradiation could effectively inactivate coronavirus. The WHO recommends the use of 0.1% sodium hypochlorite solution or an ethanol-based disinfectant with an ethanol concentration between 62% and 71%. Conclusion: The results of the present study can help researchers, policymakers, health decision makers, and people perceive and take the correct measures to control and prevent further transmission of COVID-19. Prevention and decontamination will be the main ways to stop the ongoing outbreak of COVID-19.


Assuntos
COVID-19/prevenção & controle , Desinfetantes/farmacologia , Desinfecção/instrumentação , SARS-CoV-2 , Inativação de Vírus/efeitos dos fármacos , 2-Propanol/farmacologia , Animais , COVID-19/virologia , Coronavirus Canino/efeitos dos fármacos , Desinfecção/métodos , Etanol/farmacologia , Formaldeído/farmacologia , Raios gama , Glutaral/farmacologia , Temperatura Alta , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Vírus da Hepatite Murina/efeitos dos fármacos , Povidona-Iodo/farmacologia , Vírus da SARS/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Vírus da Gastroenterite Transmissível/efeitos dos fármacos , Raios Ultravioleta
15.
Anal Methods ; 13(40): 4718-4723, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34580692

RESUMO

The traditional library least squares approach (LLS) is affected by the inconsistency of the statistical uncertainties of different channels in a gamma spectrum, which leads to large fluctuations in the analysis results. This work proposes a weighted library least squares approach (WLLS) that uses the square root of the count to weight the regression objective function and has implemented a verification experiment based on Prompt Gamma Neutron Activation Analysis (PGNAA). The results showed that, after weighing using the square root of the count, the fluctuation level of statistical uncertainty in the spectrum was reduced from 44.34 to 2.25. After the analysis of the WLLS approach, the average standard deviation of the results was reduced to at least 0.37 times that of the LLS approach.


Assuntos
Análise dos Mínimos Quadrados , Raios gama , Análise de Ativação de Nêutrons
16.
Int J Mol Sci ; 22(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34575874

RESUMO

Intestinal injury caused by ionizing radiation (IR) is a main clinical issue for patients with cancer receiving abdominal or pelvic radiotherapy. Melatonin (N-acetyl-5-methoxytryptamine) is a neurohormone that the pineal gland in the brain normally secretes. The study aimed to disclose the potential function of melatonin in intestinal injury induced by IR and its mechanism. Pretreatment with melatonin enhanced the 30-day survival rate of the irradiated mice and promoted the recovery of the intestinal epithelium and hematopoietic function following abdominal irradiation (ABI). Melatonin altered the gene profile of the small intestines from mice following ABI. The enriched biological process terms for melatonin treatment prior to radiation were mainly involved in the immune process. LPS/IL-1-mediated inhibition of RXR Function, TWEAK signaling, and Toll-like receptor signaling were the most activated canonical pathways targeted by melatonin. An upstream analysis network showed that Tripartite motif-containing 24 (TRIM24) was the most significantly inhibited and S100 calcium binding protein A9 (S100A9) activated. TRIM24 activated atherogenesis and cell viability in breast cancer cell lines and S100A9 inhibited the metabolism of amino acids. Melatonin has radioprotective effects on ABI-caused intestinal injury. The mechanisms behind the beneficial effects of melatonin were involved in activation of the immunity. It is necessary to conduct further experiments to explore the underlying mechanisms.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Transporte/genética , Intestinos/lesões , Melatonina/farmacologia , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Abdome/efeitos da radiação , Animais , Calgranulina B/metabolismo , Proteínas de Transporte/metabolismo , Sobrevivência Celular , Citocina TWEAK/metabolismo , Dano ao DNA/efeitos da radiação , Feminino , Raios gama/efeitos adversos , Hematopoese/efeitos da radiação , Humanos , Linfócitos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Nucleares/metabolismo , Fenótipo , Lesões Experimentais por Radiação/tratamento farmacológico , Radiação Ionizante , Receptores X de Retinoides/metabolismo , Fatores de Transcrição/metabolismo , Irradiação Corporal Total
17.
Int J Mol Sci ; 22(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34575973

RESUMO

Radiation damages many cellular components and disrupts cellular functions, and was previously reported to impair locomotion in the model organism Caenorhabditis elegans. However, the response to even higher doses is not clear. First, to investigate the effects of high-dose radiation on the locomotion of C. elegans, we investigated the dose range that reduces whole-body locomotion or leads to death. Irradiation was performed in the range of 0-6 kGy. In the crawling analysis, motility decreased after irradiation in a dose-dependent manner. Exposure to 6 kGy of radiation affected crawling on agar immediately and caused the complete loss of motility. Both γ-rays and carbon-ion beams significantly reduced crawling motility at 3 kGy. Next, swimming in buffer was measured as a motility index to assess the response over time after irradiation and motility similarly decreased. However, swimming partially recovered 6 h after irradiation with 3 kGy of γ-rays. To examine the possibility of a recovery mechanism, in situ GFP reporter assay of the autophagy-related gene lgg-1 was performed. The fluorescence intensity was stronger in the anterior half of the body 7 h after irradiation with 3 kGy of γ-rays. GFP::LGG-1 induction was observed in the pharynx, neurons along the body, and the intestine. Furthermore, worms were exposed to region-specific radiation with carbon-ion microbeams and the trajectory of crawling was measured by image processing. Motility was lower after anterior-half body irradiation than after posterior-half body irradiation. This further supported that the anterior half of the body is important in the locomotory response to radiation.


Assuntos
Autofagia/efeitos da radiação , Locomoção/efeitos da radiação , Doses de Radiação , Animais , Autofagia/fisiologia , Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/efeitos da radiação , Relação Dose-Resposta à Radiação , Raios gama/efeitos adversos , Humanos , Locomoção/fisiologia , Irradiação Corporal Total/efeitos adversos
18.
Int J Mol Sci ; 22(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34576334

RESUMO

Cancers are a major challenge to health worldwide. Spinel ferrites have attracted attention due to their broad theranostic applications. This study aimed at investigating the antimicrobial, antibiofilm, and anticancer activities of ebselen (Eb) and cerium-nanoparticles (Ce-NPs) in the form of ZnCexFe2-XO4 on human breast and colon cancer cell lines. Bioassays of the cytotoxic concentrations of Eb and ZnCexFe2-XO4, oxidative stress and inflammatory milieu, autophagy, apoptosis, related signalling effectors, the distribution of cells through the cell-cycle phases, and the percentage of cells with apoptosis were evaluated in cancer cell lines. Additionally, the antimicrobial and antibiofilm potential have been investigated against different pathogenic microbes. The ZOI, and MIC results indicated that ZnCexFe2-XO4; X = 0.06 specimen reduced the activity of a wide range of bacteria and unicellular fungi at low concentration including P. aeruginosa (9.5 mm; 6.250 µg/mL), S. aureus (13.2 mm; 0.390 µg/mL), and Candida albicans (13.5 mm; 0.195 µg/mL). Reaction mechanism determination indicated that after ZnCexFe2-xO4; X = 0.06 treatment, morphological differences in S.aureus were apparent with complete lysis of bacterial cells, a concomitant decrease in the viable number, and the growth of biofilm was inhibited. The combination of Eb with ZFO or ZnCexFe2-XO4 with γ-radiation exposure showed marked anti-proliferative efficacy in both cell lines, through modulating the oxidant/antioxidant machinery imbalance, restoring the fine-tuning of redox status, and promoting an anti-inflammatory milieu to prevent cancer progression, which may be a valuable therapeutic approach to cancer therapy and as a promising antimicrobial agent to reduce the pathogenic potential of the invading microbes.


Assuntos
Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Cério/farmacologia , Raios gama , Células HT29 , Humanos , Isoindóis/farmacologia , Compostos Organosselênicos/farmacologia
19.
Cells ; 10(9)2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34572124

RESUMO

Early life radiation exposure causes abnormal brain development, leading to adult depression. However, few studies have been conducted to explore pre- or post-natal irradiation-induced depression-related neuropathological changes. Relevant molecular mechanisms are also poorly understood. We induced adult depression by irradiation of mice at postnatal day 3 (P3) to reveal hippocampal neuropathological changes and investigate their molecular mechanism, focusing on MicroRNA (miR) and its target mRNA and protein. P3 mice were irradiated by γ-rays with 5Gy, and euthanized at 1, 7 and 120 days after irradiation. A behavioral test was conducted before the animals were euthanized at 120 days after irradiation. The animal brains were used for different studies including immunohistochemistry, CAP-miRSeq, Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) and western blotting. The interaction of miR-34a-5p and its target T-cell intracytoplasmic antigen-1 (Tia1) was confirmed by luciferase reporter assay. Overexpression of Tia1 in a neural stem cell (NSC) model was used to further validate findings from the mouse model. Irradiation with 5 Gy at P3 induced depression in adult mice. Animal hippocampal pathological changes included hypoplasia of the infrapyramidal blade of the stratum granulosum, aberrant and impaired cell division, and neurogenesis in the dentate gyrus. At the molecular level, upregulation of miR-34a-5p and downregulation of Tia1 mRNA were observed in both animal and neural stem cell models. The luciferase reporter assay and gene transfection studies further confirmed a direct interaction between miR-43a-5p and Tia1. Our results indicate that the early life γ-radiation-activated miR-43a-5p/Tia1 pathway is involved in the pathogenesis of adult depression. This novel finding may provide a new therapeutic target by inhibiting the miR-43a-5p/Tia1 pathway to prevent radiation-induced pathogenesis of depression.


Assuntos
Giro Denteado/patologia , Depressão/patologia , Raios gama/efeitos adversos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , MicroRNAs/genética , Neurogênese , Antígeno-1 Intracelular de Células T/metabolismo , Animais , Apoptose , Proliferação de Células , Giro Denteado/efeitos da radiação , Depressão/etiologia , Depressão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Antígeno-1 Intracelular de Células T/genética
20.
Int J Mol Sci ; 22(17)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34502232

RESUMO

Cellular senescence and its senescence-associated secretory phenotype (SASP) are widely regarded as promising therapeutic targets for aging-related diseases, such as osteoporosis. However, the expression pattern of cellular senescence and multiple SASP secretion remains unclear, thus leaving a large gap in the knowledge for a desirable intervention targeting cellular senescence. Therefore, there is a critical need to understand the molecular mechanism of SASP secretion in the bone microenvironment that can ameliorate aging-related degenerative pathologies including osteoporosis. In this study, osteocyte-like cells (MLO-Y4) were induced to cellular senescence by 2 Gy γ-rays; then, senescence phenotype changes and adverse effects of SASP on bone marrow mesenchymal stem cell (BMSC) differentiation potential were investigated. The results revealed that 2 Gy irradiation could hinder cell viability, shorten cell dendrites, and induce cellular senescence, as evidenced by the higher expression of senescence markers p16 and p21 and the elevated formation of senescence-associated heterochromatin foci (SAHF), which was accompanied by the enhanced secretion of SASP markers such as IL-1α, IL-6, MMP-3, IGFBP-6, resistin, and adiponectin. When 0.8 µM JAK1 inhibitors were added to block SASP secretion, the higher expression of SASP was blunted, but the inhibition in osteogenic and adipogenic differentiation potential of BMSCs co-cultured with irradiated MLO-Y4 cell conditioned medium (CM- 2 Gy) was alleviated. These results suggest that senescent osteocytes can perturb BMSCs' differential potential via the paracrine signaling of SASP, which was also demonstrated by in vivo experiments. In conclusion, we identified the SASP factor partially responsible for the degenerative differentiation of BMSCs, which allowed us to hypothesize that senescent osteocytes and their SASPs may contribute to radiation-induced bone loss.


Assuntos
Reabsorção Óssea/patologia , Diferenciação Celular , Senescência Celular , Raios gama/efeitos adversos , Células-Tronco Mesenquimais/patologia , Osteócitos/patologia , Comunicação Parácrina , Animais , Reabsorção Óssea/etiologia , Reabsorção Óssea/metabolismo , Masculino , Células-Tronco Mesenquimais/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Osteócitos/efeitos da radiação , Osteogênese
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