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1.
Food Chem ; 398: 133917, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987007

RESUMO

The effect of dried and UV-C-irradiated mushroom powder on lipid oxidation and vitamin D content in fish meat was investigated. To this end, Flammulina velutipes, Grifola frondosa, Hypsizygus marmoreus, Lentinula edodes, Pleurotus eryngii, Pleurotus ostreatus were dried by hot air and irradiated by UV-C and evaluated the effect of these treatments on the components. In general, the ergothioneine content did not change substantially, the total phenolic compound content decreased by hot-air drying, and the ergocalciferol content increased by UV-C irradiation. To the evaluate effect of mushroom powder on lipid oxidation and vitamin D content in fish meat, 5% of the hot air dried and UV-C-irradiated mushroom powder was added to fish meat and oxidized. Consequently, all six mushrooms prevented lipid oxidation, and ergocalciferol content in each mushroom powder remained between 58.2% and 69.7%. Overall, P. eryngii, L. edodes, and P. ostreatus strongly prevented the generation of lipid peroxide and aldehyde.


Assuntos
Agaricales , Vitamina D , Agaricales/efeitos da radiação , Animais , Ergocalciferóis , Peixes , Lipídeos , Carne , Pós , Vitaminas
2.
Toxicol In Vitro ; 86: 105503, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36273672

RESUMO

Glucose is the major source for energy production. As tumor cells have higher glucose requirement, combination of glucose restriction and radio- and chemo-therapy has been explored. In this study, impairment of UVB-induced DNA damage repair response (DDR) by glucose starvation was revealed. Human keratinocytes and skin carcinoma cells were cultured in medium containing 0, 2.5, 5.5 and 25 mM glucose. Glucose restriction suppressed cell proliferation and histone acetylation. UVB exposure formed similar levels of pyrimidine dimers in all glucose conditions, whereas the repair tended to be delayed in low glucose medium. The repair molecules, TFIIH and XPG, were accumulated to DNA damaged sites regardless of glucose supply levels, but the release was delayed in glucose-starved cells. The remaining pyrimidine dimers would induce the collapse of replication forks during S phase, resulting in phosphorylation of histone H2AX (γ-H2AX), but the γ-H2AX in cells cultured in glucose-deleted medium was unexpectedly decreased. This might be due to the suppression of DNA replication by glucose deletion. This was further confirmed by the decrease in the formation of DNA double strand breaks in glucose-starved cells. These results suggested that condition of energy supply might affect UV-induced DDR.


Assuntos
Histonas , Dímeros de Pirimidina , Humanos , Histonas/metabolismo , Glucose , Raios Ultravioleta , Reparo do DNA , Dano ao DNA , Fosforilação/efeitos da radiação , DNA
3.
Bioresour Technol ; 368: 128279, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36351532

RESUMO

Enhanced carbon capture and oxygen production via water splitting was observed by controlling the plasmon-induced resonance energy transfer (PIRET) for photosystem II (PSII) in thylakoid extracts and spirulina assembled on gold nanoparticle (AuNP) dimer arrays. The two types of vertical (V) and horizontal (H) AuNP dimer arrays were uniformly inserted inside pore diameter-controlled templates. Based on the theoretical calculations, the longitudinal mode of the H AuNP dimer array was found to be sensitive to the nanogap distances between the two AuNPs in resonance with the absorption at P680 of the PSII. The longitudinal modes that interacted with P680 of PSII increased from the V to the H conformer. The optical properties from the H AuNP dimer array caused overlapping absorbance and photoluminescence with PSII, and the H AuNP dimer arrays exhibited a significant increase in carbon capture and oxygen generation rates in comparison with those of the bare PSII protein complex under light irradiation via the controlled PIRET process.


Assuntos
Nanopartículas Metálicas , Microalgas , Complexo de Proteína do Fotossistema II/metabolismo , Tilacoides/metabolismo , Tilacoides/efeitos da radiação , Microalgas/metabolismo , Ouro , Oxigênio/metabolismo , Carbono/metabolismo
4.
J Exp Med ; 220(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36374226

RESUMO

In this issue of JEM, Jenster et al. (2022. J. Exp. Med. https://doi.org/10.1084/jem.20220837) investigate how UVB radiation promotes activation of the inflammatory immune sensor NLRP1, and in doing so uncover how NLRP1 recognizes a diverse range of ribotoxic stresses.


Assuntos
Inflamassomos , Inflamassomos/efeitos da radiação , Raios Ultravioleta , Humanos
5.
Anticancer Res ; 42(5): 2469-2477, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35489744

RESUMO

BACKGROUND/AIM: This study aimed to establish a setup for ultra-high-dose-rate (FLASH) carbon-ion irradiation, and to conduct the first human cell experiments using FLASH carbon ions. MATERIALS AND METHODS: A system for FLASH carbon-ion irradiation (1-3 Gy at 13 or 50 keV/µm) was developed. The growth and senescence of HFL1 lung fibroblasts were assessed by crystal violet staining assays and senescence-associated ß-galactosidase staining, respectively. Survival of HSGc-C5 cancer cells was assessed by clonogenic assays. RESULTS: The dose rates of carbon ions ranged from 96-195 Gy/s, meeting the definition of FLASH. With both 13 and 50 keV/µm beams, no FLASH sparing effect was observed on the growth suppression and senescence of HFL1 cells, nor on the survival of HSGc-C5 cells. CONCLUSION: We successfully conducted the first human cell experiments with FLASH carbon ions. No FLASH effect was observed under the conditions examined.


Assuntos
Carbono , Radioterapia com Íons Pesados , Fibroblastos/efeitos da radiação , Humanos , Íons
6.
Oral Oncol ; 135: 106238, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36356388

RESUMO

Functional rehabilitation remains an important factor in the post-operative period following tongue cancer surgeries. Patients undergoing surgery for tongue cancers require intense rehabilitation in order to restore their swallowing function, and improve their nutritional status and quality of life. Various swallowing scales like the Functional Oral Intake Scale (FOIS), Performance status scale in head and neck cancer (PSSHNC) and 100 ml water swallow test are used to assess functionality in these patients. These aid in timely assessment and early intervention for better rehabilitation, in turn improving quality of life. Nasogastric tube (NG) or percutaneous endoscopic gastrostomy (PEG) aids in providing adequate nutrition in the immediate post-operative period and during adjuvant therapy to overcome radiation-induced dysphagia.


Assuntos
Transtornos de Deglutição , Deglutição , Neoplasias da Língua , Humanos , Deglutição/efeitos da radiação , Transtornos de Deglutição/reabilitação , Nutrição Enteral , Gastrostomia , Qualidade de Vida , Neoplasias da Língua/cirurgia , Intubação Gastrointestinal , Endoscopia Gastrointestinal
7.
BMC Microbiol ; 22(1): 264, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333788

RESUMO

BACKGROUND: Deinococcus radiodurans (D. radiodurans) is best known for its extreme resistance to diverse environmental stress factors, including ionizing radiation (IR), ultraviolet (UV) irradiation, oxidative stress, and high temperatures. Robust DNA repair system and antioxidant system have been demonstrated to contribute to extreme resistance in D. radiodurans. However, practically all studies on the mechanism underlying D. radiodurans's extraordinary resistance relied on the treated strain during the post-treatment recovery lag phase to identify the key elements involved. The direct gene or protein changes of D. radiodurans after stress have not yet been characterized. RESULTS: In this study, we performed a proteomics profiling on D. radiodurans right after the heavy ion irradiation treatment, to discover the altered proteins that were quickly responsive to IR in D. radiodurans. Our study found that D. radiodurans shown exceptional resistance to 12C6+ heavy ion irradiation, in contrast to Escherichia coli (E.coli) strains. By using iTRAQ (Isobaric Tags for Relative and Absolute Quantitation)-based quantitative mass spectrometry analysis, the kinetics of proteome changes induced by various dosages of 12C6+ heavy ion irradiation were mapped. The results revealed that 452 proteins were differentially expressed under heavy ion irradiation, with the majority of proteins being upregulated, indicating the upregulation of functional categories of translation, TCA cycle (Tricarboxylic Acid cycle), and antioxidation regulation under heavy ion irradiation. CONCLUSIONS: This study shows how D. radiodurans reacts to exposure to 12C6+ heavy ion irradiation in terms of its overall protein expression profile. Most importantly, comparing the proteome profiling of D. radiodurans directly after heavy ion irradiation with research on the post-irradiation recovery phase would potentially provide a better understanding of mechanisms underlying the extreme radioresistance in D. radiodurans.


Assuntos
Deinococcus , Íons Pesados , Deinococcus/genética , Deinococcus/metabolismo , Deinococcus/efeitos da radiação , Proteoma/metabolismo , Proteômica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Antioxidantes/metabolismo
8.
Front Public Health ; 10: 1031743, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388350

RESUMO

Exposure to environmental ionizing radiation (IR) is ubiquitous, and large-dose exposure to IR is known to cause DNA damage and genotoxicity which is associated with an increased risk of cancer. Whether such detrimental effects are caused by exposure to low-dose IR is still debated. Therefore, rapid and early estimation of absorbed doses of IR in individuals, especially at low levels, using radiation response markers is a pivotal step for early triage during radiological incidents to provide adequate and timely clinical interventions. However, there is currently a crucial shortage of methods capable of determining the extent of low-dose IR exposure to human beings. The phosphorylation of histone H2AX on serine 139 (designated γ-H2AX), a classic biological dosimeter, can be used to evaluate the DNA damage response. We have developed an estimation assay for low-level exposure to IR based on the mass spectrometry quantification of γ-H2AX in blood. Human peripheral blood lymphocytes sensitive to low-dose IR, maintaining low temperature (4°C) and adding enzyme inhibitor are proven to be key steps, possibly insuring that a stable and marked γ-H2AX signal in blood cells exposed to low-dose IR could be detected. For the first time, DNA damage at low dose exposures to IR as low as 0.01 Gy were observed using the sensitive variation of γ-H2AX with high throughput mass spectrometry quantification in human peripheral blood, which is more accurate than the previously reported methods by virtue of isotope-dilution mass spectrometry, and can observe the time effect of DNA damage. These in vitro cellular dynamic monitoring experiments show that DNA damage occurred rapidly and then was repaired slowly over the passage of post-irradiation time even after exposure to very low IR doses. This assay was also used to assess different radiation exposures at the in vitro cellular level. These results demonstrate the potential utility of this assay in radiation biodosimetry and environmental risk assessment.


Assuntos
Linfócitos , Radiação Ionizante , Humanos , Relação Dose-Resposta à Radiação , Linfócitos/efeitos da radiação , Dano ao DNA , Espectrometria de Massas
9.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 40(10): 733-736, 2022 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-36348552

RESUMO

Objective: To investigate the effect of low-dose X-ray ionizing radiation on thyroid function of radiation workers. Methods: From January to December 2021, a total of 1039 medical workers in some tertiary hospitals in Wuhan were selected as the survey subjects, of which 518 radiation workers were selected as the exposure group, and 521 non-radiation workers were selected as the control group. The general conditions of the two groups were collected, and 5 indicators of thyroid function were measured, including total thyroxine (TT(4)) , total triiodothyronine (TT(3)) , free triiodothyronine (FT(3)) , thyroid stimulating hormone (TSH) , and free thyroxine (FT(4)) . The annual cumulative dose of ionizing radiation exposure in the exposure group was collected. Pearson χ(2) test and independent sample t test were used to compare the general conditions, 5 indicators of thyroid function and abnormal rate between the two groups. Linear regression model was used to analyze the correlation between the annual cumulative dose and 5 indicators of thyroid function in the exposure group. Binary logistic regression was used to analyze the influencing factors of thyroid dysfunction in the exposure group. Results: The TT(4) levels of the workers in the control group and the exposure group were (7.95±1.07) µg/dl and (8.26±1.41) µg/dl, respectively, and the FT(4) levels were (16.33±2.19) pmol/L and (17.15±2.42) pmol/L, respectively, the rate of thyroid dysfunction was 4.80% (25/521) and 8.49% (44/518) , and the above differences were statistically significant (P<0.05) . Linear regression analysis showed that the annual cumulative dose of the exposure group was significantly correlated with TT(4), TT(3), FT(4), and TSH (P<0.05) . For every 1 mSv increase in the annual cumulative dose, TT(4) increased by 1.661 µg/dl, FT(4) increased by 1.422 pmol/L, TT(3) decreased by 0.113 ng/ml, and TSH decreased by 0.731 µIU/ml. Binary logistic regression analysis showed that the older the radiation workers, the higher the risk of thyroid dysfunction (OR=1.080, 95% CI: 1.016-1.148, P=0.013) ; the greater the annual cumulative dose, the higher the risk of thyroid dysfunction (OR=6.400, 95%CI: 1.796-22.811, P=0.004) . Conclusion: The annual cumulative dose of low-dose X-ray ionizing radiation is positively correlated with thyroid function TT(4) and FT(4) of radiation workers, and negatively correlated with TT(3) and TSH; the greater the age and annual cumulative dose, the higher the risk of thyroid dysfunction.


Assuntos
Tiroxina , Tri-Iodotironina , Humanos , Glândula Tireoide/efeitos da radiação , Raios X , Tireotropina , Radiação Ionizante
10.
J Dent Res ; 101(13): 1645-1653, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36408969

RESUMO

Mitigation of irradiation injury to salivary glands was previously reported using a cell-free extract from mouse bone marrow. However, to bring this potential therapy a step closer to clinical application, a human bone marrow cell extract (BMCE) needs to be tested. Here, we report that irradiation-induced injury of salivary glands in immunocompetent mice treated with human BMCE secreted 50% more saliva than saline-injected mice, and BMCE did not cause additional acute inflammatory reaction. In addition, to identify the cell fraction in BMCE with the most therapeutic activity, we sorted human bone marrow into 3 cell fractions (mononuclear, granulocyte, and red blood cells) and tested their respective cell extracts. We identified that the mononuclear cell extract (MCE) provided the best therapeutic efficacy. It increased salivary flow 50% to 73% for 16 wk, preserved salivary parenchymal and stromal cells, and doubled cell proliferation rates while producing less inflammatory response. In contrast, the cell extract of granulocytes was of shorter efficacy and induced an acute inflammatory response, while that from red blood cells was not therapeutically effective for salivary function. Several proangiogenic (MMP-8, MMP-9, VEGF, uPA) and antiangiogenic factors (TSP-1, PF4, TIMP-1, PAI-1) were identified in MCE. Added advantages of BMCE and MCE for potential clinical use were that cell extracts from both male and female donors were comparably bioactive and that cell extracts could be stored and transported much more conveniently than cells. These findings suggest human BMCE, specifically the MCE fraction, is a promising therapy against irradiation-induced salivary hypofunction.


Assuntos
Lesões por Radiação , Glândulas Salivares , Humanos , Masculino , Feminino , Camundongos , Animais , Extratos Celulares/farmacologia , Glândulas Salivares/efeitos da radiação , Células da Medula Óssea , Saliva
11.
J Microbiol Biotechnol ; 32(11): 1382-1389, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36330743

RESUMO

Asterias pectinifera, a species of starfish and cause of concern in the aquaculture industry, was recently identified as a source of non-toxic and highly water-soluble collagen peptides. In this study, we investigated the antioxidant and anti-photoaging functions of compounds formulated using collagen peptides from extracts of Asterias pectinifera and Halocynthia roretzi (AH). Our results showed that AH compounds have various skin protective functions, including antioxidant effects, determined by measuring the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl radicals, as well as anti-melanogenic effects, determined by measuring tyrosinase inhibition activity. To determine whether ethosome-encapsulated AH compounds (E(AH)) exert ultraviolet (UV)-protective effects, human dermal fibroblasts or keratinocytes were incubated with E(AH) before and after exposure to UVA or UVB. E(AH) treatment led to inhibition of photoaging-induced secretion of matrix metalloproteinase-1 and interleukin-6 and -8, which are associated with inflammatory responses during UV irradiation. Finally, the antibacterial effects of AH and E(AH) were confirmed against both gram-negative and gram-positive bacteria. Our results indicate that E(AH) has the potential for use in the development of cosmetics with a range of skin protective functions.


Assuntos
Asterias , Envelhecimento da Pele , Dermatopatias , Animais , Humanos , Raios Ultravioleta , Colágeno , Pele/efeitos da radiação , Fibroblastos , Extratos Vegetais/farmacologia , Peptídeos/farmacologia , Antibacterianos/farmacologia
12.
Life Sci ; 311(Pt A): 121140, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36347324

RESUMO

AIMS: Development of novel medical countermeasures (MCMs) against acute radiation syndrome (ARS) and the associated lethality involves protection from and/or mitigation of radiation-induced hematopoietic injury, a critical clinical component of ARS. We earlier identified the molecule 7,8-diacetoxy-4-methylthiocoumarin (DAMTC) as a potent mitigator of hematopoietic injury and mortality in C57BL/6 mice when administered 24 h following total body irradiation (TBI). In the present study, we investigated mechanisms and functional relevance of immune modulation by DAMTC during the mitigation of hematopoietic injury. MAIN METHODS: C57BL/6 mice were subjected to TBI doses of 3 and 7.6Gy; administered DAMTC intra-peritoneally 24 h post TBI. Isolation, characterization, intra-cellular cytokine analysis of myeloid cells from bone marrow and spleen accompanied by flow cytometric determination and characterization of B-lymphocytes, serum isolation from peripheral blood and cytokine analysis. KEY FINDINGS: Results showed that DAMTC induced stimulation of pro-inflammatory myeloid subsets in the bone marrow and spleen of TBI mice. Further, it promoted a favorable transition from Th2 to Th1 immunity, triggered humoral immunity, and activated an intricately balanced inflammatory response that appear to contribute to immune-modulation. SIGNIFICANCE: Thus, the present study shows that immune-modulation maybe one of the contributing factors for the mitigation of hematopoietic injury by DAMTC and underscores its efficacy as a potent mitigator of hematopoietic injury that merits to be developed further as a novel MCM to combat H-ARS.


Assuntos
Lesões por Radiação , Camundongos , Animais , Camundongos Endogâmicos C57BL , Irradiação Corporal Total , Medula Óssea/efeitos da radiação , Citocinas
13.
Mar Drugs ; 20(11)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36355008

RESUMO

For this research article, we investigated the protective effects of enzyme-treated caviar powder extract (CV) in ultraviolet B (UVB)-irradiated hairless mice and keratinocytes by confirming moisturizing-related factors and elasticity-related factors. UVB irradiation induced wrinkle formation, dehydration, oxidative stress, and inflammation in the dorsal skin of mice; however, these were suppressed in the CV-supplemented groups in UVB-irradiated hairless mice. Furthermore, in UVB-irradiated keratinocytes, CV treatment increased the antioxidant enzyme activities and the levels of sphingomyelin and hyaluronic acid and decreased the production of pro-inflammatory cytokines and the expression of IkB-α and p65 phosphorylation. These findings indicate that CV can directly protect keratinocytes against UVB irradiation-induced oxidative stress and inflammation. Therefore, we suggest that CV can protect against UVB-induced skin photoaging. Therefore, we suggest that caviar is effective for skin health by preventing UVB-induced skin photoaging.


Assuntos
Envelhecimento da Pele , Camundongos , Animais , Camundongos Pelados , Raios Ultravioleta/efeitos adversos , Queratinócitos , Pele/efeitos da radiação , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Inflamação/metabolismo
14.
Nature ; 611(7935): 301-305, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36323777

RESUMO

Enrichment of nutrients and loss of herbivores are assumed to cause a loss of plant diversity in grassland ecosystems because they increase plant cover, which leads to a decrease of light in the understory1-3. Empirical tests of the role of competition for light in natural systems are based on indirect evidence, and have been a topic of debate for the last 40 years. Here we show that experimentally restoring light to understory plants in a natural grassland mitigates the loss of plant diversity that is caused by either nutrient enrichment or the absence of mammalian herbivores. The initial effect of light addition on restoring diversity under fertilization was transitory and outweighed by the greater effect of herbivory on light levels, indicating that herbivory is a major factor that controls diversity, partly through light. Our results provide direct experimental evidence, in a natural system, that competition for light is a key mechanism that contributes to the loss of biodiversity after cessation of mammalian herbivory. Our findings also show that the effects of herbivores can outpace the effects of fertilization on competition for light. Management practices that target maintaining grazing by native or domestic herbivores could therefore have applications in protecting biodiversity in grassland ecosystems, because they alleviate competition for light in the understory.


Assuntos
Biodiversidade , Herbivoria , Luz , Plantas , Animais , Pradaria , Mamíferos/fisiologia , Nutrientes/metabolismo , Plantas/classificação , Plantas/metabolismo , Plantas/efeitos da radiação , Fertilizantes
15.
Proc Natl Acad Sci U S A ; 119(45): e2211789119, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322730

RESUMO

UV radiation (UVR) has significant physiological effects on organisms living at or near the Earth's surface, yet the full suite of genes required for fitness of a photosynthetic organism in a UVR-rich environment remains unknown. This study reports a genome-wide fitness assessment of the genes that affect UVR tolerance under environmentally relevant UVR dosages in the model cyanobacterium Synechococcus elongatus PCC 7942. Our results highlight the importance of specific genes that encode proteins involved in DNA repair, glutathione synthesis, and the assembly and maintenance of photosystem II, as well as genes that encode hypothetical proteins and others without an obvious connection to canonical methods of UVR tolerance. Disruption of a gene that encodes a leucyl aminopeptidase (LAP) conferred the greatest UVR-specific decrease in fitness. Enzymatic assays demonstrated a strong pH-dependent affinity of the LAP for the dipeptide cysteinyl-glycine, suggesting an involvement in glutathione catabolism as a function of night-time cytosolic pH level. A low differential expression of the LAP gene under acute UVR exposure suggests that its relative importance would be overlooked in transcript-dependent screens. Subsequent experiments revealed a similar UVR-sensitivity phenotype in LAP knockouts of other organisms, indicating conservation of the functional role of LAPs in UVR tolerance.


Assuntos
Leucil Aminopeptidase , Raios Ultravioleta , Fotossíntese/efeitos da radiação , Reparo do DNA , Glutationa
16.
Sci Rep ; 12(1): 18907, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344673

RESUMO

Photobiomodulation (PBM) refers to the use of light to modulate cellular processes, and has demonstrated utility in improving wound healing outcomes, and reducing pain and inflammation. Despite the potential benefits of PBM, the precise molecular mechanisms through which it influences cell behavior are not yet well understood. Inconsistent reporting of key light parameters has created uncertainty around optimal exposure profiles. In addition, very low intensities of light, < 0.1 J/cm2, have not been thoroughly examined for their use in PBM. Here, we present a custom-made compact, and modular LED-based exposure system for studying the effects of very low-intensity visible light (cell proliferation, migration, ROS production, and mitochondrial membrane potential) of three different wavelengths in a parallel manner. The device allows for six repeats of three different exposure conditions plus a non-irradiated control on a single 24-well plate. The immortalised human keratinocyte cell line, HaCaT, was selected as a major cellular component of the skin epidermal barrier. Furthermore, an in vitro wound model was developed by allowing the HaCaT to form a confluent monolayer, then scratching the cells with a pipette tip to form a wound. Cells were exposed to yellow (585 nm, 0.09 mW, ~ 3.7 mJ/cm2), orange (610 nm, 0.8 mW, ~ 31 mJ/cm2), and red (660 nm, 0.8 mW, ~ 31 mJ/cm2) light for 10 min. 48 h post-irradiation, immunohistochemistry was performed to evaluate cell viability, proliferation, ROS production, and mitochondrial membrane potential. The results demonstrate increased proliferation and decreased scratch area for all exposure conditions, however only red light increased the mitochondrial activity. Oxidative stress levels did not increase for any of the exposures. The present exposure system provides opportunities to better understand the complex cellular mechanisms driven by the irradiation of skin cells with visible light.


Assuntos
Terapia com Luz de Baixa Intensidade , Humanos , Terapia com Luz de Baixa Intensidade/métodos , Espécies Reativas de Oxigênio/metabolismo , Queratinócitos/metabolismo , Cicatrização/efeitos da radiação , Proliferação de Células/efeitos da radiação , Luz
17.
J Radiol Prot ; 42(4)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36317283

RESUMO

Ultraviolet-C (UVC) radiation can effectively inactivate pathogens on surfaces and in the air. Due to the potential for harm to skin and eyes, human exposure to UVC should be limited within the guideline exposure limits produced by the International Commission on Non-Ionising Radiation Protection (ICNIRP) or the American Conference of Governmental Industrial Hygienists (ACGIHs). Both organisations state an effective spectrally weighted limit of 3 mJ cm-2, although the spectral weighting factors of the two organisations diverged following a revision of the ACGIH guidelines in 2022. Using existing published human exposure data, the effective spectrally weighted radiant exposure was calculated for both unfiltered and filtered (to reduce UV emissions above 230 nm) krypton chloride (KrCl*) excimer lamps. The effective radiant exposure of the filtered KrCl* lamp was greater than 3 mJ cm-2when applying ICNIRP or either of the revised ACGIH spectral weightings. This indicates that both guidelines are appropriately conservative for this specific lamp. However, the effective radiant exposure of the unfiltered KrCl* lamp was as low as 1 mJ cm-2with the revised ACGIH weighting function that can be applied to the skin if the eyes are protected. Erythema has therefore been directly observed in a clinical study at an exposure within the revised ACGIH guideline limits. Extrapolating this information means that a mild sunburn could be induced in Fitzpatrick skin types I and II if that particular ACGIH weighting function were applied and an individual received an effective exposure of 3 mJ cm-2. Whilst it is improbable that such an effect would be seen in current deployment of KrCl* lamp technology, it does highlight the need for further research into skin sensitivity and irradiance-time reciprocity for UVC wavelengths.


Assuntos
Criptônio , Exposição Ocupacional , Humanos , Cloretos , Raios Ultravioleta , Pele/efeitos da radiação , Exposição Ocupacional/análise
18.
PLoS One ; 17(11): e0277649, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36378669

RESUMO

California cannabis regulations require testing for four pathogenic species of Aspergillus-A. niger, A. flavus, A. fumigatus and A. terreus in cannabis flower and cannabis inhalable products. These four pathogenic species of Aspergillus are important human pathogens and their presence in cannabis flower and cannabis products may pose a threat to human health. In this study, we examined the potential of X-ray irradiation for inactivation of cannabis flower contaminated with any of the four pathogenic species of Aspergillus. We determined that X-ray irradiation at a dose of 2.5 kGy is capable of rendering Aspergillus cells non-viable at low (102 spores/g dried flower), medium (103 spores/g dried flower) and high (104 spores/g dried flower) levels of inoculation. We also showed that X-ray treatment of cannabis flower did not significantly alter the cannabinoid or the terpene profiles of the flower samples. Therefore, X-ray irradiation may be a feasible method for Aspergillus decontamination of cannabis flower. More work is required to determine the consumer safety of irradiated cannabis flower and cannabis products.


Assuntos
Cannabis , Humanos , Esporos Fúngicos/fisiologia , Raios X , Aspergillus/fisiologia , Flores , Aspergillus flavus/efeitos da radiação
19.
Int J Mol Sci ; 23(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36361775

RESUMO

Irradiation of the tumour site during treatment for cancer with external-beam ionising radiation results in a complex and dynamic series of effects in both the tumour itself and the normal tissue which surrounds it. The development of a spectral model of the effect of each exposure and interaction mode between these tissues would enable label free assessment of the effect of radiotherapeutic treatment in practice. In this study Fourier transform Infrared microspectroscopic imaging was employed to analyse an in-vitro model of radiotherapeutic treatment for prostate cancer, in which a normal cell line (PNT1A) was exposed to low-dose X-ray radiation from the scattered treatment beam, and also to irradiated cell culture medium (ICCM) from a cancer cell line exposed to a treatment relevant dose (2 Gy). Various exposure modes were studied and reference was made to previously acquired data on cellular survival and DNA double strand break damage. Spectral analysis with manifold methods, linear spectral fitting, non-linear classification and non-linear regression approaches were found to accurately segregate spectra on irradiation type and provide a comprehensive set of spectral markers which differentiate on irradiation mode and cell fate. The study demonstrates that high dose irradiation, low-dose scatter irradiation and radiation-induced bystander exposure (RIBE) signalling each produce differential effects on the cell which are observable through spectroscopic analysis.


Assuntos
Efeito Espectador , Lesões por Radiação , Masculino , Humanos , Efeito Espectador/efeitos da radiação , Quebras de DNA de Cadeia Dupla , Sobrevivência Celular/efeitos da radiação , Linhagem Celular
20.
Oxid Med Cell Longev ; 2022: 1622829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36411759

RESUMO

Deinococcus radiodurans (D. radiodurans) is an extremophile that can tolerate ionizing radiation, ultraviolet radiation, and oxidation. How D. radiodurans responds to and survives high levels of ionizing radiation is still not clear. In this study, we performed label-free proteomics to explore the proteome dynamics during postirradiation recovery (PIR). Surprisingly, proteins involved in translation were repressed during the initial hours of PIR. D. radiodurans also showed enhanced DNA repair and antioxidative response after 6 kGy of gamma irradiation. Moreover, proteins involved in sulfur metabolism and phenylalanine metabolism were enriched at 1 h and 12 h, respectively, indicating different energy and material needs during PIR. Furthermore, based on these findings, we proposed a novel model to elucidate the possible molecular mechanisms of robust radioresistance in D. radiodurans, which may serve as a reference for future radiation repair.


Assuntos
Deinococcus , Deinococcus/genética , Deinococcus/metabolismo , Deinococcus/efeitos da radiação , Raios Ultravioleta , Reparo do DNA , Radiação Ionizante , Proteoma/metabolismo
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