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1.
J Environ Sci (China) ; 150: 490-502, 2025 Apr.
Article de Anglais | MEDLINE | ID: mdl-39306423

RÉSUMÉ

The removal of ammonia nitrogen (NH4+-N) and bacteria from aquaculture wastewater holds paramount ecological and production significance. In this study, Pt/RuO2/g-C3N4 photocatalysts were prepared by depositing Pt and RuO2 particles onto g-C3N4. The physicochemical properties of photocatalysts were explored by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-vis diffuse reflectance spectrometer (UV-vis DRS). The photocatalysts were then applied to the removal of both NH4+-N and bacteria from simulated mariculture wastewater. The results clarified that the removals of both NH4+-N and bacteria were in the sequence of g-C3N4 < RuO2/g-C3N4 < Pt/g-C3N4 < Pt/RuO2/g-C3N4. This magnificent photocatalytic ability of Pt/RuO2/g-C3N4 can be interpreted by the transfer of holes from g-C3N4 to RuO2 to facilitate the in situ generation of HClO from Cl- in wastewater, while Pt extracts photogenerated electrons for H2 formation to enhance the reaction. The removal of NH4+-N and disinfection effect were more pronounced in simulated seawater than in pure water. The removal efficiency of NH4+-N increases with an increase in pH of wastewater, while the bactericidal effect was more significant under a lower pH in a pH range of 6-9. In actual seawater aquaculture wastewater, Pt/RuO2/g-C3N4 still exhibits effective removal efficiency of NH4+-N and bactericidal performance under sunlight. This study provides an alternative avenue for removement of NH4+-N and bacteria from saline waters under sunlight.


Sujet(s)
Ammoniac , Bactéries , Élimination des déchets liquides , Eaux usées , Polluants chimiques de l'eau , Eaux usées/composition chimique , Ammoniac/composition chimique , Élimination des déchets liquides/méthodes , Polluants chimiques de l'eau/composition chimique , Ruthénium/composition chimique , Lumière , Aquaculture/méthodes , Platine/composition chimique , Catalyse , Graphite , Composés de l'azote
2.
Phys Med Biol ; 2024 Oct 02.
Article de Anglais | MEDLINE | ID: mdl-39357530

RÉSUMÉ

OBJECTIVE: In this study, we present a model to correct the progressive post-irradiation darkening of EBT3 films. The model allows for a clinical use of EBT3 using application and calibration films scanned with different post-irradiation times. Approach. The model is a post-irradiation time- and dose-dependent power-law function, projecting the scanned transmittance of application films to the transmittance matching the same post-irradiation time of calibration films. The model was characterized for two EBT3 production lots within the dose range 0.1-12.8 Gy. A first characterization was performed utilizing calibration films scanned repeatedly for 54 days post-irradiation (lot 1), while a fast re-characterization of a second lot used three post-irradiation times (lot 2). For a long-term validation validation of the model, 16 film strips were irradiated at 2 Gy on different time points starting from the day of film calibration up to 43 days afterwards (lot 1). For the multi-dose validation of the model, 8 strips were irradiated with dose levels ranging 0-12 Gy deposited 25 days after the calibration (lot 2). As a proof of principle, the model was applied to four clinical patient-specific quality assurance film measurements with prescribed dose/fraction ranging 2.66 Gy-8 Gy. Main results. The post-irradiation transmittance decreased for higher doses up to -2.5% at 12.8 Gy, and 54 days post-irradiation. With a lot-specific model correction, the mean dose accuracy of validation strips that ranged from initial -3.4% (triple-channel) and -9.90% (blue-channel) reduced to within 3.0% (all colour channels) for doses above 1 Gy. The median dose difference with the planned dose improved from -3.5% to -1.1%, and the 3%/2 mm local gamma ranged from (48.5 - 92.5)% to (81.2 - 99.2)%. .

3.
Front Oncol ; 14: 1459287, 2024.
Article de Anglais | MEDLINE | ID: mdl-39351359

RÉSUMÉ

Introduction: Volumetric modulated arc therapy (VMAT) total body irradiation (TBI) allows for greater organ sparing with improved target coverage compared to 2D-TBI. However, there is limited evidence of whether improved organ sparing translates to decreases in toxicities and how its toxicities compare to those of the 2D technique. We aimed to compare differences in toxicities among patients treated with TBI utilizing VMAT and 2D techniques. Methods/materials: A matched-pair single-institution retrospective analysis of 200 patients treated with TBI from 2014 to 2023 was performed. Overall survival (OS) and progression-free survival (PFS) were analyzed using the Kaplan-Meier method and compared using log-rank tests. Differences in characteristics and toxicities between the VMAT and 2D cohorts were compared using Fisher's exact test. Results: Of the 200 patients analyzed, 100 underwent VMAT-TBI, and 100 underwent 2D-TBI. The median age for VMAT-TBI and 2D-TBI patients was 13.7 years and 16.2 years, respectively (p = 0.25). In each cohort, 53 patients were treated with myeloablative regimens (8-13.76 Gy), and 47 were treated with non-myeloablative regimens (2-4 Gy). For the entire VMAT-TBI cohort, lung Dmean, kidney Dmean, and lens Dmax were spared to 60.6% ± 5.0%, 71.0% ± 8.5%, and 90.1% ± 3.5% of prescription, respectively. For the non-myeloablative VMAT-TBI cohort, testis/ovary Dmax, brain, and thyroid Dmean were spared to 33.4% ± 7.3%, 75.4% ± 7.0%, and 76.1% ± 10.5%, respectively. For 2D-TBI, lungs were spared using partial-transmission lung blocks for myeloablative regimens. The VMAT-TBI cohort experienced significantly lower rates of any grade of pneumonitis (2% vs. 12%), nephrotoxicity (7% vs. 34%), nausea (68% vs. 81%), skin (16% vs. 35%), and graft versus host disease (GVHD) (42% vs. 62%) compared to 2D-TBI patients. For myeloablative regimen patients, rates of pneumonitis (0% vs. 17%) and nephrotoxicity (9% vs. 36%) were significantly lower with VMAT-TBI versus 2D-TBI (p < 0.01). Median follow-up was 14.3 months, and neither median OS nor PFS for the entire cohort was reached. In the VMAT versus 2D-TBI cohort, the 1-year OS was 86.0% versus 83.0% (p = 0.26), and the 1-year PFS was 86.6% and 80.0% (p = 0.36), respectively. Conclusion: Normal tissue sparing with VMAT-TBI compared to the 2D-TBI translated to significantly lower rates of pneumonitis, renal toxicity, nausea, skin toxicity, and GVHD in patients, while maintaining excellent disease control.

4.
Int J Radiat Biol ; : 1-15, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-39353463

RÉSUMÉ

PURPOSE: The study of mechanisms of plant responses to extreme conditions, particularly, microgravity and ionizing radiation, is crucial for space exploration. Modern space biology of plants focuses on increasing plant tolerance to harsh conditions of space environment. Given the limited access to the International Space Station, we designed and assembled the 3D clinostat for mimicking microgravity, which, in combination with proton irradiation, allows simulating space conditions. As a case study for testing the device, we studied the effect of clinostating on Arabidopsis thaliana accession originating from the Chernobyl exclusion zone. MATERIALS AND METHODS: Using the combined clinostating and proton irradiation, we simulated the conditions of long-term space flight for Arabidopsis thaliana plants of the Chernobyl accession - progeny of chronically irradiated plants, grown from field-collected (Masa-0) and laboratory-cultivated (Masa-0-1) seeds, and for wild-type Col-8. The clinostating and irradiation of plants were also carried out separately. Plant responses were studied as photosynthetic and phenotypic endpoints of seedlings. RESULTS AND CONCLUSIONS: Parameters of chlorophyll fluorescence estimated immediately after exposure showed that Masa-0-1 plants were resistant to the simulated space conditions, while Masa-0 demonstrated modulation of non-photochemical fluorescence quenching. Proton irradiation generally inhibited photosynthesis of Masa-0, Masa-0-1, and Col-8 seedlings. The combined effect of irradiation and clinostating modulated the photosynthetic activity of Col-8 seedlings. The leaf area of seedlings did not change after exposure to simulated conditions. The 3D clinostat model and software are published along with this article for researchers interested in the field of space biology.

5.
Head Neck ; 2024 Oct 03.
Article de Anglais | MEDLINE | ID: mdl-39363401

RÉSUMÉ

PURPOSE: Radiotherapy (RT) plays a crucial role in head and neck (HN) cancer treatment. Nevertheless, it can lead to serious and challenging adverse events such as osteoradionecrosis (ORN). A preclinical rabbit model of irradiated bone and ORN is herein proposed, with the aim to develop a viable model to be exploited for investigating new therapeutic approaches. METHODS: Nine New Zealand white rabbits were irradiated using a single beam positioned to the left of the mandible and directed perpendicular to the left mandible. A 10 × 10 mm2 region of interest (ROI) located below the first molar tooth on the left side was identified and irradiated with 7 Gy each fraction, once every 2 days, for five fractions. Dose distributions demonstrated that the corresponding ROI on the contralateral (right) mandibular side received approximately 5 Gy each fraction, thus bilateral irradiation of the mandible was achieved. ROIs were categorized as ROIH on the left side receiving the high dose and ROIL on the right side receiving the low dose. Rabbits were followed up clinically and imaged monthly. After 4 months, the irradiated bone was excised, and histological examination of ROIs was performed. RESULTS: Radiological signs suggestive for ORN were detected in the entire population (100%) 16 weeks after irradiation on ROIH, which consisted of cortical erosion and loss of trabeculae. ROIL did not show any radiological evidence of bone damage. Histologically, both sides showed comparable signs of injury, with marked reduction in osteocyte count and increase in empty lacunae count. CONCLUSIONS: A preclinical double model was successfully developed. The side receiving the higher dose showed radiological and histological signs of bone damage, resulting in an ORN model. Whereas the contralateral side, receiving the lower dose, presented with histological damage only and a normal radiological appearance. This work describes the creation of a double model, an ORN and irradiated bone model, for further study using this animal species.

6.
Appl Environ Microbiol ; : e0111324, 2024 Oct 04.
Article de Anglais | MEDLINE | ID: mdl-39365040

RÉSUMÉ

Heavy ion beam (HIB) irradiation is widely utilized in studies of cosmic rays-induced cellular effects and microbial breeding. Establishing an accurate dose-survival relationship is crucial for selecting the optimal irradiation dose. Typically, after irradiating logarithmic-phase cell suspensions with HIB, the survival fraction (SF) is determined by the ratio of clonal-forming units in irradiated versus control groups. However, our findings indicated that SF measurements were time sensitive. For the Saccharomyces cerevisiae model, the observed SF initially declined and subsequently increased in a eutrophic state; conversely, in an oligotrophic state, it remained relatively stable within 120 minutes. This time effect of SF observations in the eutrophic state can be ascribed to HIB-exposed cells experiencing cell cycle arrest, whereas the control proliferated rapidly, resulting in an over-time disproportionate change in viable cell count. Therefore, an alternative involves irradiating oligotrophic cells, determining SF thereafter, and transferring cells to the eutrophic state to facilitate DNA repair-mutation. Transcriptomic comparisons under these two trophic states yield valuable insights into the DNA damage response. Although DNA repair was postponed in an oligotrophic state, cells proactively mobilized specific repair pathways to advance this process. Effective nutritional supplementation should occur within 120 minutes, beyond this window, a decline in SF indicates an irreversible loss of repair capability. Upon transition to the eutrophic state, S. cerevisiae swiftly adapted and completed the repair. This study helps to minimize time-dependent variability in SF observations and to ensure effective damage repair and mutation in microbial breeding using HIB or other mutagens. It also promotes the understanding of microbial responses to complex environments.IMPORTANCEMutation breeding is a vital means of developing excellent microbial resources. Consequently, understanding the mechanisms through which microorganisms respond to complex environments characterized by mutagens and specific physiological-biochemical states holds significant theoretical and practical values. This study utilized Saccharomyces cerevisiae as a microbial model and highly efficient heavy ion beam (HIB) radiation as a mutagen, it revealed the time dependence of observations of survival fractions (SF) in response to HIB radiation and proposed an alternative to avoid the indeterminacy that this variable brings. Meanwhile, by incorporating an oligotrophic state into the alternative, this study constructed a dynamic map of gene expression during the fast-repair and slow-repair stages. It also highlighted the influence of trophic states on DNA repair. The findings apply to the survival-damage repair-mutation effects of single-celled microorganisms in response to various mutagens and contribute to elucidating the biological mechanisms underlying microbial survival in complex environments.

7.
Radiat Oncol ; 19(1): 135, 2024 Oct 02.
Article de Anglais | MEDLINE | ID: mdl-39358739

RÉSUMÉ

INTRODUCTION: Anaplastic meningiomas, categorized as WHO grade 3 tumors, are rare and highly aggressive, accounting for 1-2% of all meningioma cases. Despite aggressive treatment, including surgery and Radiation, they exhibit a high recurrence rate and poor survival outcomes. The aggressive histopathological features emphasize the urgent need for effective management strategies. METHODS: A retrospective multi-institutional analysis was conducted on patients with recurrent anaplastic meningioma who underwent re-irradiation between 2017 and 2023. Clinical, dosimetric, and outcome data were collected and analyzed, focusing on local control, progression free survival and treatment-related adverse events. RESULTS: Thirty-four cases were analyzed, with a median follow-up 11 months after re-irradiation. Progression-free survival at 12 months was 61.9%, with higher doses correlating with better outcomes. Concomitant Bevacizumab improves progression-free survival and reduces the risk of radiation necrosis. CDKN2A homozygote deletion correlated with a higher risk of local failure. Symptomatic radiation necrosis occurred in 20.5% of cases, but its incidence was lower with concomitant Bevacizumab treatment. CONCLUSION: Re-irradiation presents a viable option for recurrent anaplastic meningioma despite the associated risk of radiation necrosis. Higher doses with concomitant Bevacizumab improve clinical outcomes and reduce toxicity. Individualized treatment approaches are necessary, emphasizing the importance of further research to refine management strategies for this challenging disease.


Sujet(s)
Bévacizumab , Tumeurs des méninges , Méningiome , Récidive tumorale locale , Survie sans progression , Réirradiation , Humains , Méningiome/radiothérapie , Méningiome/anatomopathologie , Méningiome/mortalité , Bévacizumab/usage thérapeutique , Études rétrospectives , Adulte d'âge moyen , Mâle , Femelle , Tumeurs des méninges/radiothérapie , Tumeurs des méninges/anatomopathologie , Tumeurs des méninges/thérapie , Sujet âgé , Réirradiation/effets indésirables , Adulte , Récidive tumorale locale/anatomopathologie , Récidive tumorale locale/radiothérapie , Dosimétrie en radiothérapie , Sujet âgé de 80 ans ou plus , Antinéoplasiques immunologiques/usage thérapeutique , Taux de survie
8.
PeerJ ; 12: e18177, 2024.
Article de Anglais | MEDLINE | ID: mdl-39364362

RÉSUMÉ

Volvariella volvacea is a mushroom known for its high palatability and nutritional value. However, it is susceptible to spoilage thus making it challenging to preserve and keep fresh after harvest, resulting in constraints in long-distance transportation and long-term storage. This study aimed to investigate the feasibility of using irradiation and sodium dehydrogenate (SD) as a preservative in the preservation process of V. volvacea. The effects of three treatments of 0.8 kGy 60Coγ irradiation (B), 0.04% SD (C), combined with 0.04% SD and 0.8 kGy 60Coγ irradiation (A) on the postharvest freshness of V. volvacea were investigated. The assessment indices for V. volvacea, including appearance, browning rate, weight loss, respiration rate, MDA content, antioxidant enzyme activities, vitamin C (Vc), and soluble protein content, were measured and compared. The three treatments were compared to determine the changes in storage time over 7 days post-harvest. The results demonstrated that the hardness of the fruiting body exhibited a significant increase of 81.19%, 97.96% and 168.81% in comparison to the control, B and C, respectively, following the application of the treatment A. Compared to the control group, the soluble protein content was significantly increased by 20.28%. Respiration intensity and browning rate were significantly lower in the control treatment, decreasing by 35.07% and 45.49% respectively. On the 6th day of storage, the activities of SOD and POD increased by 81.06% and 73.71%, respectively, compared to the control, which significantly delayed the senescence of the fruiting bodies. The Vc content was significantly increased by 50.27%, 133.90%, and 101.39% in treatment B, which received 0.8 kGy 60Coγ irradiation alone, compared to the control, treatment A, and treatment C, respectively. The treatment C alone significantly reduced respiratory intensity and MDA variables by 39.55% and 31.01%, respectively, compared to the control. The findings can provide theoretical references and technical support for extending the preservation period of V. volvacea after harvesting by using irradiation and sodium dehydrogenate as a preservative.


Sujet(s)
Radio-isotopes du cobalt , Conservation aliments , Rayons gamma , Volvariella , Conservation aliments/méthodes , Antioxydants/métabolisme , Antioxydants/pharmacologie , Stockage des aliments , Corps fructifères de champignon/effets des radiations , Corps fructifères de champignon/effets des médicaments et des substances chimiques , Acide ascorbique/métabolisme
9.
Int J Oral Maxillofac Implants ; 0(0): 1-19, 2024 Oct 04.
Article de Anglais | MEDLINE | ID: mdl-39365906

RÉSUMÉ

Osseointegration of implants is significant in determining implant success. Factors influencing osseointegration include the good hydrophilicity (wettability) of the implant surface. PURPOSE: The purpose of this study was to investigate the free surface energy before and after CO2 irradiation on rough titanium surfaces. MATERIAL AND METHODS: Sandblasted, large grit, acidetched (SLA) implant surfaces were used for this study. Contact angle evaluations were performed for saline, albumin, and artificial blood using a contact angle goniometer in 25°C and 37°C (20 droplets in each group, 120 in total). The titanium disks were then irradiated with a CO2 laser (10,600 nm) using a non-contact, defocused, 2W continuous wave for 30 seconds. Contact angle measurements for saline, albumin and artificial blood were evaluated immediately after irradiation (new 120 in total contact angle measurements) and compared with the measurements before laser irradiation. Paired t-test using SPSS was performed for 5% statistical significance level. RESULTS: Lower numbers of contact angle measurements were found and changes after CO2-laser irradiation were statistically significant (p < 0.05) for all groups except for albumin at 25°C, as follows: 25℃: (saline) (Pre) 111.97° ±13.67°, (Post) 79.29° ±10.83° / p<0.0001; (albumin) (Pre) 89.04° ±12.02°, (Post) 83.29° ±20.71° / p=0.297; (blood) (Pre) 97.79° ±14.44°, (Post) 86.29° ±10.82° / p=0.019; 37℃: (saline) (Pre) 104.12° ±13.138°, (Post) 92.66° ±4.777° / p=0.001; (albumin) (Pre) 89.04° ±12.02°, (Post) 83.29° ±20.71° / p=0.297 (blood) (Pre) 80.42° ±19.00°, (Post) 58.62° ±24.34° / p=0.012. CONCLUSION: The CO2 laser irradiation in general positively affected the wettability and hydrophilicity of rough titanium (SLA) surfaces.

10.
Ann Med Surg (Lond) ; 86(10): 5793-5801, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39359823

RÉSUMÉ

Radiotherapy is widely regarded as the primary therapeutic modality for nasopharyngeal cancer (NPC). Studies have shown that cancer cells with high resistance to radiation, known as radioresistant cancer cells, may cause residual illness, which in turn might contribute to the occurrence of cancer recurrence and metastasis. It has been shown that cancer stem-like cells (CSCs) exhibit resistance to radiation therapy. In the present study, fractionated doses of radiation-induced epithelial-mesenchymal transition (EMT) and ALDH+ CSCs phenotype of NPC tumor spheroids. Furthermore, it has been shown that cells with elevated ALDH activity have increased resistance to the effects of fractionated irradiation. Nuclear factor erythroid-2-related factor 2 (Nrf2) plays a pivotal role in regulating cellular antioxidant systems. A large body of evidence suggests that Nrf2 plays a significant role in the development of radioresistance in cancer. The authors' research revealed that the application of fractionated irradiation resulted in a decline in Nrf2-dependent reactive oxygen species (ROS) levels, thereby mitigating DNA damage in ALDH+ stem-like NPC cells. In addition, immunofluorescence analysis revealed that subsequent to the process of fractionated irradiation of ALDH+ cells, activated Nrf2 was predominantly localized inside the nucleus. Immunofluorescent analysis also revealed that the presence of the nuclear Nrf2+/NQO1+/ALDH1+ axis might potentially serve as an indicator of poor prognosis and resistance to radiotherapy in patients with NPC. Thus, the authors' findings strongly suggest that the radioresistance of ALDH-positive NPC CSCs to fractionated irradiation is regulated by nuclear Nrf2 accumulation. Nrf2 exerts its effects through the downstream effector NQO1/ALDH1, which depends on ROS attenuation.

11.
Prev Nutr Food Sci ; 29(3): 354-364, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39371519

RÉSUMÉ

Exogenous proline can improve the growth, aroma intensities, and bioactive compounds of rice. This study evaluated the effects of gamma irradiation under proline conditions on the 2-acetyl-1-pyrroline (2AP), phenolic, and flavonoid contents of rice. Moreover, the bioactive compounds of gamma-irradiated rice under proline conditions that inhibited α-glucosidase and α-amylase were evaluated by in silico study. A low gamma dose (40 Gy) induced the highest rice growth under 5 mM proline concentration. The highest 2AP content was stimulated at a gamma dose of 5-100 Gy under 10 mM proline concentration. At 500 and 1,000 Gy gamma dose, the highest flavonoid and phenolic contents of rice were stimulated. 1-(2-Hydroxy-5-methylphenyl)-ethanone, which had the highest binding affinity (-7.9 kcal/mol) against α-glucosidase, was obtained at 500 and 1,000 Gy gamma dose under 5 and 10 mM proline concentrations. Meanwhile, 6-amino-1,3,5-triazine-2,4(1H,3H)-dione, which had the highest binding affinity (-6.3 kcal/mol) against α-amylase, was obtained under 10 mM proline concentration in non-gamma-irradiated rice. The results indicate that using a combination of gamma irradiation and exogenous proline is suitable for producing new rice varieties. Moreover, the bioactive compounds that were obtained in new rice varieties exhibited health benefits, especially for diabetes mellitus treatment (inhibition of α-glucosidase and α-amylase).

12.
J Hazard Mater ; 480: 135991, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39369677

RÉSUMÉ

Algae-derived organic matter (ADOM) is a key source of chromophoric dissolved organic matter (CDOM) in natural waters. When exposed to solar irradiation, ADOM undergoes gradual degradation and transformation. The escalating presence of microplastics (MPs) can act as a novel type of environmental photosensitizer, however its impacts on ADOM photodegradation remains largely unexplored. Thus, in this study, ADOM were extracted from four common algal species (Microcystis aeruginosa, Synechococcus sp., Chlorella pyrenoidosa and Scenedesmus obliquus) and exposed to UV irradiation with or without polystyrene (PS) MPs, namely ADOM+PS groups and ADOM groups, respectively. The results indicated that a more rapid degradation of amino acid-like substances (∼38 % vs. ∼22 %) and more ammonia products (1.86 vs. 1.21 mg L-1) were observed in the ADOM+PS groups compared to the ADOM groups after a five-day exposure. This enhanced photodegradation might be attributed to the production of environmentally persistent free radicals and reactive species during the photoaging of PS. Furthermore, PS-derived high electron transfer belt activity of ADOM led to the production of highly aromatic and humified products. These humic-like products could potentially accelerate the degradation of amino acid-like compounds by exciting the generation of excited triplet CDOM. This study underscores the role of MPs as environmental photosensitizers in promoting ADOM degradation and ammonia generation, providing insights on the transformation of ADOM mediated by emerging pollutants and its impact on aquatic carbon and nitrogen cycles.

13.
J Radiat Res ; 2024 Oct 10.
Article de Anglais | MEDLINE | ID: mdl-39388726

RÉSUMÉ

Neutron-activated 31Si is an almost pure beta emitter and is one of the short-lived radionuclides, including beta-gamma emitter 56Mn, which were created in a form of residual radioactivity in the early period after the atomic bombing of Hiroshima and Nagasaki. The features of the biological effects of internal irradiation by these radionuclides are a subject of scientific discussions and research. The publication presents data on internal radiation doses in experimental Wistar rats that were exposed to sprayed neutron-activated microparticles of 31SiO2. Doses of internal radiation could be conditionally divided into three groups according to their values. It has been found that elevated values of internal radiation doses in rats' organs/tissues as a result of exposure to sprayed 31SiO2 microparticles with initial activity of 3.2 × 107 Bq varied from 10 to 120 mGy (eyes, lungs, skin, stomach, jejunum, large intestine). The moderate dose values were in the range from 1.9 to 3.7 mGy (trachea, esophagus, ileum). The smallest doses were received by the kidney, testis, blood, cerebellum, heart, liver, cerebrum, bladder, spleen and thymus (from 0.11 to 0.94 mGy). The obtained data are important for interpreting the results of ongoing and planned biological experiments with 31SiO2 microparticles-in comparison with the previously published data on features of biological effects caused by beta-gamma emitting 56MnO2 neutron-activated microparticles.

14.
Food Chem ; 463(Pt 4): 141482, 2024 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-39388885

RÉSUMÉ

Spreading serves as a pivotal process in the flavor development of green tea. In this study, the effects of spreading under five light irradiation on the volatile and non-volatile metabolites of green tea were comprehensively investigated using intelligent sensory technologies integrated with targeted and non-targeted metabolomics analyses. The incorporation of yellow light irradiation into spreading process significantly improved the overall quality of green tea. A total of 71 volatile and 112 non-volatile metabolites were identified by GC-MS/MS and UHPLC-Q-Exactive/MS, respectively. Among them, 20 key odorants with OAVs exceeding 1 were screened out. Moreover, phenylethyl alcohol, ß-damascenone, ß-ionone, (E, Z)-2,6-nonadienal, linalool, and phenylacetaldehyde with higher OAVs were pivotal contributors to the aroma quality under different light irradiation. Additionally, 13 non-volatile metabolites with VIP > 1.2 were recognized as key differential metabolites under different light irradiation. The results provide technical support and theoretical guidance for enhancing the processing technology of green tea.

15.
Phys Med ; 127: 104825, 2024 Oct 07.
Article de Anglais | MEDLINE | ID: mdl-39378781

RÉSUMÉ

PURPOSE: This study aims to emphasize the necessity of a focal irradiation tool for small animals and compare the beam characteristics of a tool developed using a brachytherapy system with a linear accelerator (LINAC)-based tool. METHODS: A 1-mm tungsten collimator was designed for a Ir-192 brachytherapy system. The percent depth dose (PDD) and horizontal profile of the collimator were measured and compared with a 4-mm commercial cone in the LINAC. Monte Carlo simulations validated all the measurements. Mouse brains were irradiated using a focal irradiation tool, and immunohistochemistry was performed on the brain samples to assess the dose accuracy. RESULTS: PDD showed that the maximum dose (dmax) for Ir-192 was at the surface in both measurements and simulations. At a depth of 1 mm, the collimator measured doses of 25.6 % and 21.0 %, respectively. At 6 MV in the LINAC, the dmax was observed at depths of 0.7 and 0.8 cm in measurements and simulations, respectively. The full width at half maximum (FWHM) at a depth of 1 mm was 1.0 and 1.1 mm for Ir-192 in the measurements and simulations, respectively. For small cone sizes at dmax, FWHM was 4.0 and 4.1 mm for the measurements and simulations, respectively. Immunohistochemistry results indicated that focal irradiation with Ir-192 affected small superficial brain areas while sparing the contralateral side and subventricular zone. CONCLUSION: The focal irradiation tool accurately delivered doses to small regions and shallow depths in the mouse brain, making it valuable for precise radiotherapy during small animal experiments.

16.
Thorac Cancer ; 2024 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-39380451

RÉSUMÉ

Prophylactic cranial irradiation (PCI) was recommended for limited-stage small-cell lung cancer (SCLC) patients with complete or partial response to primary chemoradiotherapy. But it is still controversial regarding its role in SCLC patients who have had radical resection. This meta-analysis aims to evaluate the efficacy of PCI in resected SCLC patients. We searched PubMed, EMBASE, Web of Science, CENTRAl, and ClinicalTrials for controlled trials and cohort studies regarding PCI in postoperative SCLC patients. The correlation between PCI and post-operative outcomes in SCLC patients, including survival and brain metastasis rate (BMR), was examined using hazard ratios (HRs) and risk ratios with corresponding 95% confidence intervals. Quality of studies was assessed by the Newcastle-Ottawa Scale (NOS), and publication bias was assessed by Begg's test. Meta-analysis of eight studies with 2688 patients in total showed PCI was associated with improved overall survival (OS) for resected SCLC (HR: 0.65, 95% CI: 0.57-0.75, p < 0.01). In addition, subgroup analysis on three studies including 923 patients confirmed the protective role of postoperative PCI in N0 SCLC patients (HR: 0.79, 95% CI: 0.61-0.97, p < 0.05). There was also a significant reduction in BMR in the PCI group pooled from six studies (HR: 0.58, 95% CI: 0.40-0.85, p < 0.01). The use of PCI delayed brain recurrence and improved OS in patients with resected, stage I-III SCLC. Importantly, patients with N0 SCLC can also benefit from postoperative PCI. In future studies, PCI's role in patients with resected N0 SCLC at different T stage may need to be explored.

17.
Stem Cell Res Ther ; 15(1): 348, 2024 Oct 08.
Article de Anglais | MEDLINE | ID: mdl-39380035

RÉSUMÉ

BACKGROUND: Vasoactive intestinal peptide (VIP) is a neuronal peptide with prominent distribution along the enteric nervous system. While effects of VIP on intestinal motility, mucosal vasodilation, secretion, and mucosal immune cell function are well-studied, the direct impact of VIP on intestinal epithelial cell turnover and differentiation remains less understood. Intestinal stem and progenitor cells are essential for the maintenance of intestinal homeostasis and regeneration, and their functions can be modulated by factors of the stem cell niche, including neuronal mediators. Here, we investigated the role of VIP in regulating intestinal epithelial homeostasis and regeneration following irradiation-induced injury. METHODS: Jejunal organoids were derived from male and female C57Bl6/J, Lgr5-EGFP-IRES-CreERT2 or Lgr5-EGFP-IRES-CreERT2/R26R-LSL-TdTomato mice and treated with VIP prior to analysis. Injury conditions were induced by exposing organoids to 6 Gy of irradiation (IR). To investigate protective effects of VIP in vivo, mice received 12 Gy of abdominal IR followed by intraperitoneal injections of VIP. RESULTS: We observed that VIP promotes epithelial differentiation towards a secretory phenotype predominantly via the p38 MAPK pathway. Moreover, VIP prominently modulated epithelial proliferation as well as the number and proliferative activity of Lgr5-EGFP+ progenitor cells under homeostatic conditions. In the context of acute irradiation injury in vitro, we observed that IR injury renders Lgr5-EGFP+ progenitor cells more susceptible to VIP-induced modulations, which coincided with the strong promotion of epithelial regeneration by VIP. Finally, the observed effects translate into an in vivo model of abdominal irradiation, where VIP showed to prominently mitigate radiation-induced injury. CONCLUSIONS: VIP prominently governs intestinal homeostasis by regulating epithelial progenitor cell proliferation and differentiation and promotes intestinal regeneration following acute irradiation injury.


Sujet(s)
Différenciation cellulaire , Souris de lignée C57BL , Peptide vasoactif intestinal , Animaux , Peptide vasoactif intestinal/métabolisme , Peptide vasoactif intestinal/pharmacologie , Souris , Mâle , Femelle , Lésions radiques/métabolisme , Lésions radiques/anatomopathologie , Muqueuse intestinale/métabolisme , Muqueuse intestinale/effets des radiations , Muqueuse intestinale/anatomopathologie , Organoïdes/métabolisme , Cellules souches/métabolisme , Cellules souches/effets des médicaments et des substances chimiques , Cellules souches/effets des radiations
18.
Int J Radiat Biol ; : 1-9, 2024 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-39383240

RÉSUMÉ

In the short-season winter environment of India and Bangladesh, lentil growth and seed yield are significantly hindered by foliar blight caused by Stemphylium botryosum. As the international germplasm pool lacks a resistance source, the study aims to develop a mutant population to identify a high-yielding mutant resistance against the pathogen. A gamma-irradiated population was developed based on its GR50 dose of 248.8 Gy. The screening of almost 130,000 M2 plants identified a tolerant lentil mutant, MM216. The multi-location trials revealed that MM216 showed an impressive and robust resistance; the selected mutant line could be recommended as a donor in the lentil breeding program against the pathogen globally. A 100 g seed was exposed to a GR50 dose to develop the M1 population. At maturity, at least 100 M2 seeds of each 1300 M1 plant were harvested individually. So, almost 130,000 M2 plants were screened in the disease hot spot. The selected mutants were advanced to M7 by screening in the field and challenged in controlled conditions with the pure pathogen isolate. A resistance mutant, MM216, with a per cent disease index (PDI) of <10, was identified where the mean of the check varieties, WBL 77, was >55. The resistance ability was confirmed further in controlled conditions. The fungal and plant DNA ratio was almost negligible in the tolerant mutant, whereas it was 0.17 in WBL77 at 196 h post-inoculation. The selected mutant did not display any yield penalty, but there was a delay in flowering by a week compared to WBL77.

19.
Angew Chem Int Ed Engl ; : e202414943, 2024 Oct 07.
Article de Anglais | MEDLINE | ID: mdl-39375148

RÉSUMÉ

Precious metals are valuable materials for the chemical industry, but they are scarce and pose a risk of supply disruption. Recycling precious metals from waste is a promising strategy, here we tactfully utilize light irradiation as an environmental-friendly and energy-saving adjunctive strategy to promote the reduction of precious metal ions, thereby improving the adsorption capacity and kinetics. A newly light-sensitive covalent organic framework (PP-COF) was synthesized to illustrate the effectiveness and feasibility of this light auxiliary strategy. The equilibrium adsorption capacities of PP-COF with light irradiation towards gold, platinum, and silver ions are 4729, 573, and 519 mg g-1, which are 3.3, 1.9, and 1.2 times the adsorption capacities under dark condition. Significantly, a filtration column with PP-COF can recover more than 99.8% of the gold ions in the simulated e-waste leachates with light irradiation, and 1 gram of PP-COF can recover gold from up to 0.15 tonne of e-waste leachates. Interestingly, the captured precious metals by PP-COF with light irradiation mainly exist in the micron-sized particles, which can be easily separated by extraction. We believe this work can contribute to precious metal recovery and circular economy for recycling resources.

20.
Bot Stud ; 65(1): 30, 2024 Oct 08.
Article de Anglais | MEDLINE | ID: mdl-39377879

RÉSUMÉ

BACKGROUND: Cucumber (Cucumis sativus L.) is a model crop to study cell biology, including the development of haploids and doubled haploids in vegetable crops. In plant breeding, haploid and doubled haploids are valuable tools for developing pure homozygous inbred lines and accelerating genetic progress by reducing the time required for breeding cycles. Besides, the haploids are also valuable in genomic studies. We are reporting the induction of haploids in cucumber involving gynoecious and parthenocarpic genotypes for the first time. This study aimed to assess the efficient induction of haploids through pollination with gamma-irradiated pollen in cucumber. The effect of gamma irradiation dose on pollen viability and germination, fruit setting percentage, seed development, and haploid embryo development in cucumber hybrid genotypes were studied in detail. The goal was to utilize this information to produce haploid plants for genomics and transformation works in this model vegetable crop. RESULTS: Pollination was done on six cucumber genotypes using varying doses of gamma rays (100, 200, 300, 400, and 500 Gy). Genotypes, doses of irradiation, and embryo developmental stage influenced the successful generation of in-vitro haploid plants. The optimal timeframe for embryo rescue was found to be 25 to 30 days after pollination. Haploid embryos were effectively induced using irradiated pollen at 400 to 500 Gy doses. Parthenogenetic plantlets were analyzed, and their ploidy level was confirmed through stomatal physiology, cytology (mitosis), and flow cytometry methods. CONCLUSION: Through parthenogenic embryo development, it is possible to induce a large number of haploids in cucumber. This technique's power lies in its ability to streamline the breeding process, enhance genetic gain, and produce superior cultivars that contribute to sustainable agriculture and food security.

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