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1.
Int J Mol Sci ; 25(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39201326

RESUMO

This comprehensive review critically examines the current state of research on the biological effects of millimeter-wave (MMW) therapy and its potential implications for disease treatment. By investigating both the thermal and non-thermal impacts of MMWs, we elucidate cellular-level alterations, including changes in ion channels and signaling pathways. Our analysis encompasses MMW's therapeutic prospects in oncology, such as inducing apoptosis, managing pain, and modulating immunity through cytokine regulation and immune cell activation. By employing a rigorous methodology involving an extensive database search and stringent inclusion criteria, we emphasize the need for standardized protocols to enhance the reliability of future research. Although MMWs exhibit promising therapeutic potential, our findings highlight the urgent need for further elucidation of non-thermal mechanisms and rigorous safety assessments, considering the intricate nature of MMW interactions and inconsistent study outcomes. This review underscores the importance of focused research on the biological mechanisms of MMWs and the identification of optimal frequencies to fully harness their therapeutic capabilities. However, we acknowledge the challenges of variable study quality and the necessity for advanced quality control measures to ensure the reproducibility and comparability of future investigations. In conclusion, while MMW therapy holds promise as a novel therapeutic modality, further research is imperative to unravel its complex biological effects, establish safety profiles, and optimize treatment protocols before widespread clinical application.


Assuntos
Neoplasias , Humanos , Animais , Neoplasias/terapia , Micro-Ondas , Apoptose , Transdução de Sinais
2.
Molecules ; 29(20)2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39459266

RESUMO

At present, the effects of environmental electromagnetic irradiation on the metabolism of organisms have attracted extensive attention, but the mechanism is still not clear. D-glucose plays an important role in the metabolism of organisms. In this work, the change in the optical rotation of D-glucose solution under an electrostatic field is measured experimentally, so as to explain the mechanism of the electric field-induced biological effect. The experimental results show that the electrostatic field can alter the optical rotation of D-glucose solution at different temperatures. Under the different strengths of electrostatic field, the specific rotation of D-glucose solution increases at different temperatures; the maximum increase can reach 2.07%, but the effect of temperature and electric field strength on the rotation increment is nonlinear and very complex. Further, it turns out that the proportion of α-D-glucose in solution increases by up to 3.25% under the electrostatic field, while the proportion of ß-D-glucose decreases by as much as 1.75%. The experimental study confirms that electrostatic field can change the proportion of two conformation molecules (α and ß-D-glucose) in D-glucose solution, which can provide a novel explanation for the mechanism of the electric field-induced biological effect.


Assuntos
Glucose , Eletricidade Estática , Glucose/química , Rotação Ocular , Soluções , Temperatura
3.
Electromagn Biol Med ; : 1-9, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361824

RESUMO

The electromagnetic waves of 2.45 GHz microwave frequency have become abundant in environments worldwide. This study assessed the short-term impact of low-intensity 2.45 GHz exposure on young Arabidopsis thaliana plants. The plants underwent a 48-hour exposure to continuous wave 2.45 GHz microwaves at a power density of 1.0 ± 0.1 W m-2. Experiments were conducted inside anechoic chambers. After the microwave exposure samples were subjected to morphological, genotoxicity, pigmentation, and physiochemical analysis. Microwave exposure elevated the levels of photosynthetic pigments, oxidative stress, guaiacol peroxidase activity, and ascorbic peroxidase activity in plants. Conversely, catalase activity decreased. Photosystem efficiency remained unchanged, while non-photochemical quenching increased. Leaf morphological parameters exhibited no significant alterations during this brief exposure period. Notably, despite shifts in physiological parameters and pigmentations, genomic template stability remained unaffected. The findings suggest that the non-thermal effects of microwave exposure influence the photosystem and plant physiology. Research confirmed the existence of non-thermal effects of microwave exposure; however, these effects are within tolerable limits for Arabidopsis thaliana plants.


Microwaves are a category of radio waves with wavelengths ranging from approximately 30 centimeters to one millimeter. The most utilized microwave frequency these days is 2.45GHz, which is used in everyday devices such as microwaves and WiFi signals. This investigation explored the impact of low-intensity 2.45GHz microwaves on young thale cress (Arabidopsis thaliana) plants for 48hours. In other words, research is comparable to scientific assessing how plants respond to the proximity of a 2G WiFi signal. The exposure resulted in increased pigment production in plants and displayed indications of stress, influencing specific plant activities. However, these alterations did not compromise the stability of the genetic materials of the plants. This suggests that although low-intensity microwaves can affect plant systems, the effects appear to be manageable during brief exposures.

4.
Environ Sci Technol ; 57(29): 10591-10603, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37341092

RESUMO

Exposure to chemical pollution can induce genetic and epigenetic alterations, developmental changes, and reproductive disorders, leading to population declines in polluted environments. These effects are triggered by chemical modifications of DNA nucleobases (DNA adducts) and epigenetic dysregulation. However, linking DNA adducts to the pollution load in situ remains challenging, and the lack of evidence-based DNA adductome response to pollution hampers the development and application of DNA adducts as biomarkers for environmental health assessment. Here, we provide the first evidence for pollution effects on the DNA modifications in wild populations of Baltic sentinel species, the amphipod Monoporeia affinis. A workflow based on high-resolution mass spectrometry to screen and characterize genomic DNA modifications was developed, and its applicability was demonstrated by profiling DNA modifications in the amphipods collected in areas with varying pollution loads. Then, the correlations between adducts and the contaminants level (polycyclic aromatic hydrocarbons (PAHs), trace metals, and pollution indices) in the sediments at the collection sites were evaluated. A total of 119 putative adducts were detected, and some (5-me-dC, N6-me-dA, 8-oxo-dG, and dI) were structurally characterized. The DNA adductome profiles, including epigenetic modifications, differed between the animals collected in areas with high and low contaminant levels. Furthermore, the correlations between the adducts and PAHs were similar across the congeners, indicating possible additive effects. Also, high-mass adducts had significantly more positive correlations with PAHs than low-mass adducts. By contrast, correlations between the DNA adducts and trace metals were stronger and more variable than for PAHs, indicating metal-specific effects. These associations between DNA adducts and environmental contaminants provide a new venue for characterizing genome-wide exposure effects in wild populations and apply DNA modifications in the effect-based assessment of chemical pollution.


Assuntos
Adutos de DNA , Hidrocarbonetos Policíclicos Aromáticos , Animais , DNA , Poluição Ambiental/análise , Sedimentos Geológicos/química
5.
Cancer Sci ; 113(2): 721-732, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34935247

RESUMO

Synovial sarcomas are rare tumors arising in adolescents and young adults. The prognosis for advanced disease is poor, with an overall survival of 12-18 months. Frizzled homolog 10 (FZD10) is overexpressed in most synovial sarcomas, making it a promising therapeutic target. The results of a phase 1 trial of ß-radioimmunotherapy (RIT) with the 90 Y-labeled anti-FZD10 antibody OTSA101 revealed a need for improved efficacy. The present study evaluated the potential of α-RIT with OTSA101 labeled with the α-emitter 225 Ac. Competitive inhibition and cell binding assays showed that specific binding of 225 Ac-labeled OTSA101 to SYO-1 synovial sarcoma cells was comparable to that of the imaging agent 111 In-labeled OTSA101. Biodistribution studies showed high uptake in SYO-1 tumors and low uptake in normal organs, except for blood. Dosimetric studies showed that the biologically effective dose (BED) of 225 Ac-labeled OTSA101 for tumors was 7.8 Bd higher than that of 90 Y-labeled OTSA101. 90 Y- and 225 Ac-labeled OTSA101 decreased tumor volume and prolonged survival. 225 Ac-labeled OTSA101 achieved a complete response in 60% of mice, and no recurrence was observed. 225 Ac-labeled OTSA101 induced a larger amount of necrosis and apoptosis than 90 Y-labeled OTSA101, although the cell proliferation decrease was comparable. The BED for normal organs and tissues was tolerable; no treatment-related mortality or obvious toxicity, except for temporary body weight loss, was observed. 225 Ac-labeled OTSA101 provided a high BED for tumors and achieved a 60% complete response in the synovial sarcoma mouse model SYO-1. RIT with 225 Ac-labeled OTSA101 is a promising therapeutic option for synovial sarcoma.


Assuntos
Actínio/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Receptores Frizzled/antagonistas & inibidores , Sarcoma Sinovial/radioterapia , Actínio/química , Actínio/farmacocinética , Partículas alfa/uso terapêutico , Animais , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/farmacocinética , Linhagem Celular Tumoral , Receptores Frizzled/imunologia , Receptores Frizzled/metabolismo , Humanos , Camundongos , Radioimunoterapia , Dosagem Radioterapêutica , Indução de Remissão , Sarcoma Sinovial/metabolismo , Sarcoma Sinovial/patologia , Distribuição Tecidual/efeitos da radiação , Carga Tumoral/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto , Radioisótopos de Ítrio/química , Radioisótopos de Ítrio/farmacocinética , Radioisótopos de Ítrio/uso terapêutico
6.
Ecotoxicol Environ Saf ; 241: 113784, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35738101

RESUMO

Sedaxane was a novel chiral fungicide that contains four enantiomers. Unfortunately, the stereoselective bioactivity, toxicity and degradation of sedaxane have not been clarified. In this study, we identified the absolute configuration of the four sedaxane enantiomers at first time. The stereoselective bioactivity toward three wheat and rice pathogens, stereoselective acute toxicity to aquatic organisms (Selenastrum capricornutum and Daphnia magna), and stereoselective degradation of sedaxane were studied. The 1 S,2S-(+)-sedaxane possessed 5.4-7.3 times greater bioactivity than 1 R,2R-(-)-sedaxane to Rhizoctonia solani and Rhizoctonia cerealis. Contrarily, the 1 R,2S-(+)-sedaxane had 4.2 times greater activity than 1 S,2S-(+)-sedaxane against Fusarium graminearum. The 1 R,2R-(-)-sedaxane had 2.8 times greater toxicity than 1 S,2S-(+)-sedaxane to S. capricornutum. The chiral determination method used ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The recovery of sedaxane stereoisomers ranged from 83.1 % to 98.2 %, with RSDs (Relative standard deviations) of 1.2 %- 8.4 %. The trans-sedaxane existed stereoselective degradation phenomenon in the rice-wheat rotation mode, and 1 S,2S-(+)-sedaxane was preferentially degraded. Our results would provide scientific importance and practical guidance to the safety evaluation of chiral pesticides.


Assuntos
Fungicidas Industriais , Oryza , Anilidas , Cromatografia Líquida , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Pirazóis , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos , Triazóis/química , Triticum
7.
Ecotoxicol Environ Saf ; 246: 114194, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36252513

RESUMO

The potential toxicity of microplastic (MPs) to organisms has attracted extensive attention. However, due to the subacute toxicity of MPs, the biological effect is hard to verify in short-term exposure experiment. Here, by tracking the dynamics of gut microbes, mice model was utilized to evaluate the toxicity of compositional MPs (PE, PET, PP, PS and PVC). After 7 days digestive exposure, the physiological indicators were normal as the control group that the body weight and serum cholesterol levels were insignificant change. Whereas, through histopathological examination, all the treatment groups suffered colon tissue damage, among which PS had the most inflammatory cells. Moreover, the high-throughput sequencing results revealed great variation of intestinal flora in treated mice. The ratio of Bacteroidetes and Firmicutes in PE, PET and PP treatment groups heighten, and the relative abundance of Ruminococcaceae and Lachnospiraceae increased significantly at family levels. At the genus level, Alistipes bacteria in PS treatment group significantly decreased that is associated with obesity risk. It indicated that MPs induced inflammatory response would further interfere the dynamics of intestinal flora causing health effect in living organisms. This work shed light on MPs toxicity in short-term exposure and supplied research paradigm of MPs health risk assessment.


Assuntos
Microbioma Gastrointestinal , Microplásticos , Camundongos , Animais , Plásticos , Bactérias/genética , Digestão
8.
Molecules ; 27(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144576

RESUMO

Magnetic nanoparticles (MNPs) are becoming important DNA nanocarriers for genetic engineering of industrial fungi. However, the biological effect of MNPs on industrial fungi remains unknown. In this study, we prepared three kinds of magnetic nanoparticles with different sizes (i.e., 10 nm, 20 nm, and 200 nm) to investigate their impact on the growth and sporulation of the important industrial fungus Aspergillus niger. Transmission electron microscopy, X-ray diffraction analysis and Zeta potential analysis revealed that the three kinds of MNPs, including MNP10, MNP20 and MNP200, had uniform size distribution, regular Fe3O4 X-ray diffraction (XRD) patterns and similar Zeta potentials. Interestingly, although the three kinds of MNPs did not obviously inhibit growth of the fungus, the MNP20 at 500 mg/L strongly attenuated sporulation, leading to a remarkable decrease in spore numbers on culturing plates. Further investigation showed that MNP20 at the high concentration led to drastic chitin accumulation in the cell wall, indicating cell wall disruption of the MNP20-treated fungal cells. Moreover, the MNPs did not cause unusual iron dissolution and reactive oxygen species (ROS) accumulation, and the addition of ferrous ion, ferric ion or the reactive oxygen species scavenger N-acetyl-L-cysteine (NAC) had no impact on the sporulation of the fungus, suggesting that both iron dissolution and ROS accumulation did not contribute to attenuated sporulation by MNP20. This study revealed the size-dependent effect of MNPs on fungal sporulation, which was associated with MNP-induced cell wall disruption.


Assuntos
Nanopartículas de Magnetita , Acetilcisteína , Aspergillus niger , Quitina , DNA , Ferro , Espécies Reativas de Oxigênio
9.
Molecules ; 27(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36014466

RESUMO

Euphorbia resinifera latex has been extensively utilized in traditional medicine due to its range of bioactivities. Chromatographic separations on silica gel of ethanol extract of E. resinifera latex led to the development of a new procedure for isolating resiniferatoxin (4) via dried E. resinifera latex and the identification of nine compounds. Among these, catechol (7), protocatechuic acid (8) and 3,4-dihydroxyphenylacetic acid (9), known phenolic compounds, were identified for the first time in E. resinifera latex. Herein we investigated the effects of major compounds of the latex of E. resinifera on the yeast Saccharomyces cerevisiae, on the growth of Aspergillus carbonarius, a widespread fungal contaminant, and on the breast cancer cell line MCF7 as well as on MCF10A normal breast cells. 12-deoxyphorbol-13-isobutyrate-20-acetate (2) had an inhibiting effect on the growth of A. carbonarius, and 7-p-metoxyphenylacetate-3,8,12-triacetate ingol (3) showed a negative effect on yeast cell growth and also a cytotoxic effect on breast cancer cell line MCF7, but not on MCF10A cells. Deglucosyl euphorbioside A (5) and euphorbioside A (6) showed a discoloration effect that was possibly related to mitochondrial functionality in yeast, and also cytotoxicity only on the cancer cell line that was tested. Interestingly, treatment of MCF7 cells with 7-p-metoxyphenylacetate-3,8,12-triacetate ingol (3) and deglucosyl euphorbioside A (5) not only led to a specific cytotoxic effect but also to the increase in the level of intracellular ROS.


Assuntos
Antineoplásicos , Neoplasias da Mama , Diterpenos , Euphorbia , Antifúngicos , Antineoplásicos/farmacologia , Diterpenos/química , Euphorbia/química , Feminino , Humanos , Látex/química , Saccharomyces cerevisiae
10.
Int J Environ Health Res ; 32(4): 916-940, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32885667

RESUMO

The advent of wireless technologies has revolutionized the way we communicate. The steady upsurge in the use of mobile phone all over the world in the last two decades, while triggered economic growth, has caused substantial damage to the environment, both directly and indirectly. The electromagnetic radiation generated from mobile phones, radio-based stations, and phone towers, high-voltage power lines have been reported which leads to the variety of health scares such as the risk of cancer in human beings and adverse effects in animals, birds, etc. Though the usage of such radiation emitting from mobile phones has risen steeply, there is a lack of proper knowledge about the associated risks. The review provides the latest research evidence based both on in vitro studies, in vivo studies, and possible gaps in our knowledge. Moreover, the present review also summarizes available literature in this subject, reports and studies which will help to form guidelines for its exposure limits to the public.Abbreviations: Continuous Wave: CW; Code Division Multiple Access: CDMA; Global System for Mobile Communications: GSM; Peripheral Blood Mononuclear Cell: PBMC; Radiofrequency: RF; Radiofrequency radiation: RFR; Universal Mobile Telecommunications System: UMTS; Wideband Code Division Multiple Access: WCDMA; Specific Absorption Rate: SAR; National Toxicology Program: NTP; amplitude-modulated or amplitude-modulation: AM; Electromagnetic frequencies: EMF; confidence interval: CI; Gigahertz: GHz; odds ratio: OR; incidence ratio: IR; reactive oxygen species: ROS; specific absorption rate: SAR; International Agency of Research on Cancer: IARC; single-strand breaks: SSB; double-strand breaks: DSB (7,12-Dimethylbenz[a]anthracene): DMBA; Hour: h; international commission on non-ionizing radiation protection: ICNIRP; extremely low frequency: ELFl; microtesla: mT; Gigahertz: GHz; hertz: Hz; decibel: dB; kilometer: Km; Watt per square meter: W/m2; Hour: h; positron emission tomography: PET.


Assuntos
Telefone Celular , Leucócitos Mononucleares , Animais , Carcinógenos , Campos Eletromagnéticos , Humanos , Ondas de Rádio , Espécies Reativas de Oxigênio
11.
Rep Pract Oncol Radiother ; 27(2): 344-351, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299375

RESUMO

FLASH radiotherapy (RT) is a technique involving the delivery of ultra-high dose rate radiation to the target. FLASH-RT has been shown to reduce radiation-induced toxicity in healthy tissues without compromising the anti-cancer effects of treatment compared to conventional radiation therapy. In the present article, we review the published data on FLASH-RT and discuss the current state of knowledge of this novel approach. We also highlight the technological constraints and complexity of FLASH-RT and describe the physics underlying this modality, particularly how technology supports energy transfer by ionising radiation (e.g., beam on/off sequence, pulse-energy load, intervals). We emphasise that current preclinical experience is mostly based on FLASH electrons and that clinical application of FLASH-RT is very limited. The incorporation of FLASH-RT into routine clinical radiotherapy will require the development of devices capable of producing FLASH photon beams.

12.
Cancer Cell Int ; 21(1): 68, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482824

RESUMO

BACKGROUND: MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) could interact with each other to play a vital role in the pathogenesis of cancers. We aimed to examine the expression profile, clinical significance and regulatory relationship of miR-130a-3p and its predicted interactive lncRNA in clear cell renal cell carcinoma (ccRCC). METHODS: Bioinformatics analysis was used to predict lncRNAs binding with miR-130a-3p. qRT-PCR was employed to detect the expression levels of miR-130a-3p and the miRNA-targeted lncRNA, and their clinical values in ccRCC were clarified. The lncRNA sponge potential of miR-130a-3p was assessed through dual-luciferase reporter assay and the biological effects of them were observed. RESULTS: Colon cancer associated transcript 1 (CCAT1) directly interacted with miR-130a-3p and negatively regulated miR-130a-3p expression. CCAT1 was upregulated and miR-130a-3p was downregulated in ccRCC cell line and tissues (all P < 0.05). High CCAT1 and low miR-130a-3p expression was correlated with larger tumor size and advanced TNM stage in ccRCC patients. High CCAT1 level suggested a poor survival prognosis. There was a negative association between CCAT1 and miR-130a-3p expression (r = - 0.373, P = 0.010). MiR-130a-3p mimic and si-CCAT1 inhibited ccRCC cell proliferation and invasion, and induced apoptosis. CONCLUSIONS: CCAT1/miR-130a-3p axis may have potential to serve as a novel diagnostic and prognostic target of ccRCC patients.

13.
Bioelectromagnetics ; 42(6): 501-515, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34233018

RESUMO

In magnetobiology, it is difficult to reproduce the nonspecific (not associated with specialized receptors) biological effects of weak magnetic fields. This means that some important characteristic of the data may be missed in standard statistical processing, where the set of measurements to be averaged belongs to the same population so that the contribution of fluctuations decreases according to the Central Limit Theorem. It has been shown that a series of measurements of a nonspecific magnetic effect contains not only the usual scatter of data around the mean but also a significant random component in the mean itself. This random component indicates that measurements belong to different statistical populations, which requires special processing. This component, otherwise called heterogeneity, is an additional characteristic that is typically overlooked, and which reduces reproducibility. The current method for studying and summarizing highly heterogeneous data is the random-effect meta-analysis of absolute values, i.e., of magnitudes, rather than the values themselves. However, this estimator-the average of absolute values-has a significant positive bias when it comes to the small effects that are characteristic of magnetobiology. To solve this problem, an improved estimator based on the folded normal distribution that gives several times less bias is proposed. We used this improved estimator to analyze the nonspecific effect of the hypomagnetic field in the Stroop test in 40 subjects and found a statistically significant meta-effect with a standardized average of magnitudes of about 0.1. It has been shown that the proposed approach can also be applied to a single study. © 2021 Bioelectromagnetics Society.


Assuntos
Reprodutibilidade dos Testes , Humanos , Distribuição Normal
14.
Ecotoxicol Environ Saf ; 194: 110354, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135378

RESUMO

With the rapid development of ultra high voltage alternating current (UHV AC) transmission, the intensity of environmental power frequency electric field (PFEF) near UHV AC transmission lines increased continuously, which has attracted considerable public attention on the potential health effects of PFEF. In this study, the effect of PFEF exposure on the kidney was explored. Institute of Cancer Research (ICR) mice were exposed to 35 kV/m PFEF (50 Hz). Two indicators relating to renal function (urea nitrogen and creatinine) were tested after the exposure of 7d, 14d, 21d, 35d and 49d. The pathological morphology and cellular ultrastructure of kidney were observed respectively by light microscopy and electron microscopy after the exposure of 25d and 52d. Results showed that compared with that of the control group, the concentration of urea nitrogen of 35 kV/m PFEF exposure group significantly increased on the 21st and 35th days, and the concentration of creatinine significantly increased on the 14th, 21st and 35th days. However, the concentrations of creatinine and urea nitrogen both returned to normal levels on the 49th day. Furthermore, an enlarged Bowman's space, the vacuolation of renal tubular epithelial cells and the foot process effacement of podocyte were found after 25d exposure, but no abnormality was observed after 52d exposure. Obviously, a short-term (35d) exposure of 35 kV/m PFEF could cause kidney injury, which could be recovered after a longer-term (52d) exposure. Based on this study and relevant literatures, one explanation for this two-way effect is as follows. Kidney injury was caused by the disequilibrium of mitochondrial dynamics under 35 kV/m PFEF exposure. PFEF could also activate Wnt/ß-catenin signal to promote the recovery of renal tubular epithelial cells and glomerular podocytes, so kidney injury could be repaired.


Assuntos
Eletricidade , Exposição Ambiental , Rim/fisiologia , Animais , Rim/patologia , Masculino , Camundongos , Eletricidade Estática
15.
Electromagn Biol Med ; 39(4): 419-432, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33023315

RESUMO

Low-frequency vibrational excitations of protein macromolecules in the terahertz frequency region are suggested to contribute to many biological processes such as enzymatic catalysis, intra-protein energy/charge transport, recognition, and allostery. To explain high effectiveness of these processes, two possible mechanisms of the long-lived excitation were proposed by H. Fröhlich and A.S. Davydov, which relate to either vibrational modes or solitary waves, respectively. In this paper, we developed a quantum dynamic model of vibrational excitation in α-helical proteins interacting with the aqueous environment. In the model, we distinguished three coupled subsystems, i.e., (i) a chain of hydrogen-bonded peptide groups (PGs), interacting with (ii) the subsystem of the side-chain residuals which in turn interact with (iii) the environment, surrounding water responsible for dissipation and fluctuation in the system. It was shown that the equation of motion for phonon variables of the PG chain can be transformed to nonlinear Schrodinger equation which admits bifurcation into the solution corresponding to the weak-damped vibrational modes (Fröhlich-type regime) and Davydov solitons. A bifurcation parameter is derived through the strength of phonon-phonon interaction between the side-chains and hydration-shell water molecules. As shown, the energy of these excited states is pumped through the interaction of the side-chains with fluctuating water environment of the proteins. The suggested mechanism of the collective vibrational mode excitation is discussed in connection with the recent experiments on the long-lived collective protein excitations in the terahertz frequency region and vibrational energy transport pathways in proteins.


Assuntos
Modelos Moleculares , Proteínas/química , Água/química , Ligação de Hidrogênio , Conformação Proteica em alfa-Hélice , Proteínas/metabolismo , Vibração
16.
Cas Lek Cesk ; 159(7-8): 258-260, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33445930

RESUMO

Ionizing radiation refers to the flow of material particles or photons of electromagnetic radiation that can ionize atoms of the environment through which it passes. At the cellular level, damage can be manifested by cell death or changing their cytogenetic information. These events can lead to adverse tissue reactions (deterministic effects) in which manifestations depend on exceeding the dose threshold, or to the stochastic effects, when the probability of damage increases with the dose. This article briefly summarizes these effects on the human body.


Assuntos
Radiação Ionizante , Relação Dose-Resposta à Radiação , Humanos
17.
J Environ Sci (China) ; 94: 119-127, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563475

RESUMO

Currently, the wastewater treatment plants (WWTPs) attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants discharge. However, they have not been able to satisfy the increasing ecological safety needs. In this study, the removal of micropollutants was investigated, and the ecological safety was assessed for a local WWTP. Although the total concentration of 31 micropollutants detected was reduced by 83% using the traditional biological treatment processes, the results did not reflect chemicals that had poor removal efficiencies and low concentrations. Of the five categories of micropollutants, herbicides, insecticides, and bactericides were difficult to remove, pharmaceuticals and UV filters were effectively eliminated. The specific photosynthesis inhibition effect and non-specific bioluminescence inhibition effect from wastewater were detected and evaluated using hazardous concentration where 5% of aquatic organisms are affected. The photosynthesis inhibition effect from wastewater in the WWTP was negligible, even the untreated raw wastewater. However, the bioluminescence inhibition effect from wastewater which was defined as the priority biological effect, posed potential ecological risk. To decrease non-specific biological effects, especially of macromolecular dissolved organic matter, overall pollutant reduction strategy is necessary. Meanwhile, the ozonation process was used to further decrease the bioluminescence inhibition effects from the secondary effluent; ≥ 0.34 g O3/g DOC of ozone dose was recommended for micropollutants elimination control and ecological safety.


Assuntos
Ozônio , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos , Águas Residuárias/análise
18.
J Pharmacol Sci ; 140(1): 8-13, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31105023

RESUMO

Understanding how natural compounds work together for disease treatments can improve their clinical efficacy and therapeutic effects. To elucidate the mechanisms of synergistic biological effects in natural compound mixtures, umbelliferone (UMB, 7-hydroxycoumarin), derived from Angelica (A.) gigas, was selected as active compound with fluorescent characteristic to examine bioactivities in vitro in the presence of other compounds from Angelica gigas. Antioxidant effects of UMB in biochemical assays and cellular reactive oxygen species (ROS) levels in RAW264.7 cells were not significantly improved by addition of other compounds. However, intracellular uptake, inhibition of the efflux pump P-glycoprotein (P-gp), and physiological stability of UMB were greatly enhanced by the addition of other compounds, specifically Angelicin (ANG) and Byakangelicin (BYN). Taken together, enhanced intracellular localization and enzymatic stability in compound mixtures might lead to superior synergistic bioactivity of UMBs in compound mixtures.


Assuntos
Angelica/química , Antioxidantes/metabolismo , Estabilidade de Medicamentos , Sinergismo Farmacológico , Umbeliferonas/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Antioxidantes/isolamento & purificação , Furocumarinas/farmacologia , Camundongos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Umbeliferonas/isolamento & purificação
19.
J Toxicol Environ Health A ; 82(20): 1069-1075, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31760910

RESUMO

Cerium oxide (CeO2), one of many engineered nanomaterials (ENMs), is composed primarily of metal oxides, such as cerium oxide (CeO2). CeO2-containing materials are widely used as a polishing agent for glass mirrors, plate glass, television tubes, ophthalmic lenses, and precision optics. The widespread use of this nanomaterial (NM) resulted in increased environmental contamination levels and consequent human exposure. However, the influence of Ce on humans remains to be determined. The aim of this study was to expose female ICR mice to varying nanoparticle sizes of 35 nm, 300 nm as well as a mixture of 1-5 µM CeO2 particles through intranasal (i.n.) instillation at 40 mg/kg dose on day 1, 3 and 5, and the experiment terminated on day 7. Histopathology findings demonstrated that hydropic degeneration was prominently associated with hemorrhage in renal cortex and medulla in all CeO2-administered groups. In liver of CeO2-exposed mice, hydropic degeneration was also prominent. Serum chemistries also indicated signs of renal and hepatic lesion as evidenced by significantly decreased serum levels of total bilirubin (TBIL) and total phosphate (TP) and activity of alkaline phosphatase (ALP). ICP-MS analysis group demonstrated that Ce levels were not significantly higher in liver and kidneys of mice exposed to 35 nm CeO2. An increase in Ce content was observed in hepatic and renal tissues of mice exposed to 300 nm or 1-5 µM CeO2. The levels of Ce were similar in these two groups suggesting a threshold level of Ce was attained regardless of NP size. Data thus demonstrated that i.n. instillation of different-sized CeO2 particles translocated to liver and kidney and that size difference of CeO2 particles did not exert significant in the observed histopathology responses.


Assuntos
Cério/administração & dosagem , Rim/metabolismo , Fígado/metabolismo , Nanopartículas Metálicas/administração & dosagem , Administração Intranasal , Animais , Feminino , Camundongos , Camundongos Endogâmicos ICR , Tamanho da Partícula
20.
J UOEH ; 41(1): 1-14, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30867395

RESUMO

The main objective of this study was to evaluate the risk of the respiratory diseases, i.e. pneumoconiosis, lung fibrosis, granulomatous pneumonitis, lung cancer and bronchial asthma, which have been reported as related to toner exposure. The second main objective was to clarify the association between toner exposure and parameters related with toner-handling worker's health. We conducted a 10-year prospective cohort study from 2004 to 2013 in 296 Japanese toner-handling workers. The evaluation of toner exposure and medical health check were performed once a year. There was no obvious evidence of occurrence of lung diseases. We also investigated several health parameters to recognize the change of respiratory health before onset of pneumoconiosis, lung fibrosis, lung cancer and bronchial asthma. However there were some sporadic statistically significant findings, to bring all health parameters, we did not find obvious evidence that toner exposure would cause adverse health effects as a whole. We concluded that the possibility that toner exposure would cause adverse health effects was quite low.


Assuntos
Pneumopatias/etiologia , Exposição Ocupacional/efeitos adversos , Impressão , Fuligem/efeitos adversos , Adulto , Povo Asiático , Feminino , Humanos , Pneumopatias/epidemiologia , Masculino , Estudos Prospectivos , Risco , Fatores de Tempo
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