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International Journal of Molecular... Jun 2024Although the moderate thermal stimulation of articular cartilage exerts chondroprotective effects, it is difficult to effectively heat deep articular cartilage with...
Although the moderate thermal stimulation of articular cartilage exerts chondroprotective effects, it is difficult to effectively heat deep articular cartilage with conventional methods. Photosensitizers increase the ambient temperature using near-infrared (NIR) radiation, which has high tissue permeability. We hypothesized that the intra-articular administration of photosensitizers and NIR irradiation would exert a greater heating effect on articular cartilage. We aimed to evaluate the heating effect of this method on cultured chondrocytes and rat knee cartilage. In vitro, we irradiated a photosensitizer-containing medium with NIR and measured changes in the medium temperature, cytotoxicity, and gene expression of heat shock protein () and aggrecan (). In vivo, the knee joints of rats treated with photosensitizers were irradiated with NIR, and changes in intra-articular temperature and gene expression were measured, alongside histological analysis. The results showed that the medium and intra-articular temperature were raised to approximately 40 °C with no apparent disruption to articular cartilage or the immunohistochemically enhanced staining of HSP70 in chondrocytes. The gene expression of and was increased in both cultured and articular cartilage. In summary, this method can safely heat joints and enhance cartilage metabolism by inducing HSP70 expression in articular cartilage. It presents a new hyperthermia therapy with effective cartilage protection.
Topics: Animals; Rats; Cartilage, Articular; Chondrocytes; Photosensitizing Agents; HSP70 Heat-Shock Proteins; Aggrecans; Male; Cells, Cultured; Rats, Sprague-Dawley; Infrared Rays; Hyperthermia, Induced
PubMed: 38928434
DOI: 10.3390/ijms25126728 -
Bioengineering (Basel, Switzerland) Jun 2024This study assessed AI-processed low-dose cone-beam computed tomography (CBCT) images for single-tooth diagnosis. Human-equivalent phantoms were used to evaluate CBCT...
This study assessed AI-processed low-dose cone-beam computed tomography (CBCT) images for single-tooth diagnosis. Human-equivalent phantoms were used to evaluate CBCT image quality with a focus on the right mandibular first molar. Two CBCT machines were used for evaluation. The first CBCT machine was used for the experimental group, in which images were acquired using four protocols and enhanced with AI processing to improve quality. The other machine was used for the control group, where images were taken in one protocol without AI processing. The dose-area product (DAP) was measured for each protocol. Subjective clinical image quality was assessed twice by five dentists, with a 2-month interval in between, using 11 parameters and a six-point rating scale. Agreement and statistical significance were assessed with Fleiss' kappa coefficient and intra-class correlation coefficient. The AI-processed protocols exhibited lower DAP/field of view values than non-processed protocols, while demonstrating subjective clinical evaluation results comparable to those of non-processed protocols. The Fleiss' kappa coefficient value revealed statistical significance and substantial agreement. The intra-class correlation coefficient showed statistical significance and almost perfect agreement. These findings highlight the importance of minimizing radiation exposure while maintaining diagnostic quality as the usage of CBCT increases in single-tooth diagnosis.
PubMed: 38927812
DOI: 10.3390/bioengineering11060576 -
Photochemistry and Photobiology Jun 2024Tree shade, particularly shade that obscures direct sunlight near peak periods of midday solar exposure can have a pronounced effect on potentially harmful ultraviolet...
Tree shade, particularly shade that obscures direct sunlight near peak periods of midday solar exposure can have a pronounced effect on potentially harmful ultraviolet radiation, and in turn, strongly influence the maximum daily UV index (UVI). In this study, the seasonal influence of tree shade on the UVI is evaluated from 210 hemispherical sky view images collected alongside public walkways and footpaths from 10 residential Brisbane suburbs. The effective sidewalk UV index is calculated underneath planted tree canopies, adjacent residential gardens, buildings and background tree species. Results are presented with respect to seasonal variations in the diurnal solar elevation for each month of the year at Brisbane's latitude. The research also examines the total reduction in UVI due to the presence of individual tree species, showing reductions in the midday UVI of up to 91% of an equivalent unimpeded sky hemisphere when overhead tree canopies are present. Important footpath tree species for peak midday UVI mitigation include Pongamia pinnata, Xanthostemon chrysanthus, Senna siamea, and Libidibia ferrea. The planting and maintenance of existing tree species already growing alongside residential Brisbane streets will improve the shade characteristics of suburbs and enhance UV protection for local residents.
PubMed: 38926941
DOI: 10.1111/php.13988 -
Scientific Reports Jun 2024Occupational radiation protection should be applied to the design of treatment rooms for various radiation therapy techniques, including BNCT, where escaping particles...
Occupational radiation protection should be applied to the design of treatment rooms for various radiation therapy techniques, including BNCT, where escaping particles from the beam port of the beam shaping assembly (BSA) may reach the walls or penetrate through the entrance door. The focus of the present study is to design an alternative shielding material, other than the conventional material of lead, that can be considered as the material used in the door and be able to effectively absorb the BSA neutrons which have slowed down to the thermal energy range of eV after passing through the walls and the maze of the room. To this aim, a thermal neutron shield, composed of polymer composite and polyethylene, has been simulated using the Geant4 Monte Carlo code. The neutron flux and dose values were predicted using an artificial neural network (ANN), eliminating the need for time-consuming Monte Carlo simulations in all possible suggestions. Additionally, this technique enables simultaneous optimization of the parameters involved, which is more effective than the traditional sequential and separate optimization process. The results indicated that the optimized shielding material, chosen through ANN calculations that determined the appropriate thickness and weight percent of its compositions, can decrease the dose behind the door to lower than the allowable limit for occupational exposure. The stability of ANN was tested by considering uncertainties with the Gaussian distributions of random numbers to the testing data. The results are promising as they indicate that ANNs could be used as a reliable tool for accurately predicting the dosimetric results, providing a drastically powerful alternative approach to the time-consuming Monte Carlo simulations.
PubMed: 38926477
DOI: 10.1038/s41598-024-65207-w -
Journal of the European Academy of... Jul 2024This review aimed at summarizing some of the key points that were discussed during the photoprotection session at the International Forum of Dermatology in 2022. This... (Review)
Review
This review aimed at summarizing some of the key points that were discussed during the photoprotection session at the International Forum of Dermatology in 2022. This international conference was designed to address prominent topics of clinical dermatology in a holistic way, allowing to articulate multiple viewpoints. Therefore, this review does not claim to be exhaustive, but is instead intended to give an overview of recent developments and ongoing controversies in the field of photoprotection. Cumulative ultraviolet radiation (UVR) exposure is the major aetiological factor in the development of photoageing, photoimunosuppression and photocarcinogenesis. UVA (320-400 nm) penetrates into the dermis and damages DNA and other intracellular and acellular targets primarily by generating reactive oxygen species (ROS). It is the major contributor to photoageing, characterized by fine and coarse wrinkles, dyspigmentation and loss of elasticity. UVB (290-320 nm) is responsible for sunburns through direct damage to DNA by the formation of 6-4 cyclobutane pyrimidine dimers (CPDs) and pyrimidine 6-4 pyrimidone photoproducts. Both UVA and UVB exposure increase the risk of basal cell carcinoma, squamous cell carcinoma and melanoma. In recent years, visible light (VL; 400-700 nm) has also been implicated in the exacerbation of conditions aggravated by sun exposure such as hyperpigmentation and melasma. Photoprotection is a critical health strategy to reduce the deleterious effects of UVR and VL. Comprehensive photoprotection strategies include staying in the shade when outdoors, wearing photoprotective clothing including a wide-brimmed hat, and sunglasses, and the use of sunscreen. Due to the absorption of UV filters, the safety of sunscreens has been questioned. Newer sunscreens are becoming available with filters with absorption even beyond the UV spectrum, offering enhanced protection compared with older products. Prevention of photocarcinogenesis, sun-induced or sunlight-exacerbated hyperpigmentary conditions and drug-induced photosensitivity is an important reason for adopting comprehensive photoprotection strategies.
Topics: Humans; Sunscreening Agents; Ultraviolet Rays; Skin Aging; Skin Neoplasms; Sunburn
PubMed: 38924160
DOI: 10.1111/jdv.19677 -
Medical Physics Jun 2024Historically, [I]I has been a common isotope in radionuclide therapy, with [Lu]Lu-labelled radiopharmaceuticals now seeing a surge in use. These can include...
BACKGROUND
Historically, [I]I has been a common isotope in radionuclide therapy, with [Lu]Lu-labelled radiopharmaceuticals now seeing a surge in use. These can include no-carrier-added or carrier-added [Lu]Lu with slight impurities of [Lu]Lu with a significantly longer half-life than [I]I. Wastewater from therapy wards can contain a mixture of these radioisotopes. In some countries, national regulations require wastewater to be stored in dedicated systems before it is discharged into the public sewage system. To fulfill legal requirements, the nuclide specific activity concentration must be verified.
PURPOSE
We evaluate a method for determining the activity concentration of [Lu]Lu /[Lu]Lu at equilibrium and [I]I in pure and mixed samples in order to prove that the determined values are reliably below the limits for release.
METHODS
We analysed the emitted energy spectrum of 1 L samples with a wastewater counter using an energy window-based approach by evaluating measurements from two different time points. Based on the law of decay and the time and energy-dependent measured values, equation systems were set up to calculate the count rates for [I]I and [Lu]Lu, which were converted into activity concentration using calibration factors.
RESULTS
There is strong linear correlation between the nominal and determined activity concentrations (correlation coefficients R = 0.99; coefficient of determinations R = 0.99). We underestimate the actual activity concentration by a median of -1.4% for [Lu]Lu and overestimate the activity concentration for [I]I by a median of 7.1%.
CONCLUSION
We show that an undercut of the clearance levels for material release is measurable. We analyse and determine activity concentrations of mixed samples consisting of [I]I and [Lu]Lu/[Lu]Lu in equilibrium. The method is simple to implement using a conventional wastewater counter, however with a slightly increased effort, as two samples and measurements are required. The methodology can be adapted for the analysis of other nuclide mixtures.
PubMed: 38922963
DOI: 10.1002/mp.17272 -
Toxics Jun 2024Bisphenol A (BPA), a typical endocrine disruptor, is known to have various adverse effects on the male reproductive system. However, the toxic effects and mechanisms of...
Bisphenol A (BPA), a typical endocrine disruptor, is known to have various adverse effects on the male reproductive system. However, the toxic effects and mechanisms of low-dose BPA have not yet been fully explored. In this study, male Kunming mice were orally administered low-dose BPA (0.03, 0.3 and 3 mg/kg/d) for ten consecutive weeks. Pathological sections of testicular tissue showed no significant morphological differences after BPA exposure. An analysis of the functional parameters of sperm revealed that exposure to low-dose BPA significantly decreased sperm motility, chemotaxis, and the acrosome reaction. An in vitro BPA exposure model combined with an omics data analysis showed that the olfactory receptor-related pathway was significantly enriched after BPA treatment. Subsequent experiments verified the reduced mRNA level of a novel olfactory receptor gene, , in vivo and in vitro exposure models. Meanwhile, exposure to low-dose BPA reduced the intracellular calcium ion concentration and the mRNA levels of pore-forming subunits of the CatSper channel in sperm. Importantly, the knockdown of Olfr25 inhibited calcium ion levels and CatSper subunit expression in GC-2 cells. Olfr25 overexpression attenuated the BPA-induced downregulation of CatSper subunit expression in GC-2 cells. These findings indicate that Olfr25 might participate in low-dose BPA-induced sperm dysfunction by affecting the CatSper-Ca signaling pathway. This study reveals a new mechanism underlying the effects of low-dose BPA on sperm function and provides a reference for assessing the safety of low-dose BPA exposure.
PubMed: 38922122
DOI: 10.3390/toxics12060442 -
Nanomaterials (Basel, Switzerland) Jun 2024Intelligent and diversified development of modern detection technology greatly affects the battlefield survivability of military targets, especially infrared, acoustic... (Review)
Review
Intelligent and diversified development of modern detection technology greatly affects the battlefield survivability of military targets, especially infrared, acoustic wave, and radar detection expose targets by capturing their unavoidable infrared radiation, acoustic wave, and electromagnetic wave information, greatly affecting their battlefield survival and penetration capabilities. Therefore, there is an urgent need to develop stealth-protective materials that can suppress infrared radiation, reduce acoustic characteristics, and weaken electromagnetic signals. Fibrous three-dimensional porous materials, with their high porosity, excellent structural adjustability, and superior mechanical properties, possess strong potential for development in the field of stealth protection. This article introduced and reviewed the characteristics and development process of fibrous three-dimensional porous materials at both the micrometer and nanometer scales. Then, the process and characteristics of preparing fibrous three-dimensional porous materials through vacuum forming, gel solidification, freeze-casting, and impregnation stacking methods were analyzed and discussed. Meanwhile, their current application status in infrared, acoustic wave, and radar stealth fields was summarized and their existing problems and development trends in these areas from the perspectives of preparation processes and applicability were analyzed. Finally, several prospects for the current challenges faced by fibrous three-dimensional porous materials were proposed as follows: functionally modifying fibers to enhance their applicability through self-cross-linking; establishing theoretical models for the transmission of thermal energy, acoustic waves, and electromagnetic waves within fibrous porous materials; constructing fibrous porous materials resistant to impact, shear, and fracture to meet the needs of practical applications; developing multifunctional stealth fibrous porous materials to confer full-spectrum broadband stealth capability; and exploring the relationship between material size and mechanical properties as a basis for preparing large-scale samples that meet the application's requirement. This review is very timely and aims to focus researchers' attention on the importance and research progress of fibrous porous materials in the field of stealth protection, so as to solve the problems and challenges of fibrous porous materials in the field of stealth protection and to promote the further innovation of fibrous porous materials in terms of structure and function.
PubMed: 38921879
DOI: 10.3390/nano14121003 -
Biotech (Basel (Switzerland)) Jun 2024(1) Background: DNA damage is of great importance in the understanding of the effects of ionizing radiation. Various types of DNA damage can result from exposure to...
(1) Background: DNA damage is of great importance in the understanding of the effects of ionizing radiation. Various types of DNA damage can result from exposure to ionizing radiation, with clustered types considered the most important for radiobiological effects. (2) Methods: The code RITRACKS (Relativistic Ion Tracks), a program that simulates stochastic radiation track structures, was used to simulate DNA damage by photons and ions spanning a broad range of linear energy transfer (LET) values. To perform these simulations, the transport code was modified to include cross sections for the interactions of ions or electrons with DNA and amino acids for ionizations, dissociative electron attachment, and elastic collisions. The radiochemistry simulations were performed using a step-by-step algorithm that follows the evolution of all particles in time, including reactions between radicals and DNA structures and amino acids. Furthermore, detailed DNA damage events, such as base pair positions, DNA fragment lengths, and fragment yields, were recorded. (3) Results: We report simulation results using photons and the ions H, He, C, O, and Fe at various energies, covering LET values from 0.3 to 164 keV/µm, and performed a comparison with other codes and experimental results. The results show evidence of DNA protection from damage at its points of contacts with histone proteins. (4) Conclusions: RITRACKS can provide a framework for studying DNA damage from a variety of ionizing radiation sources with detailed representations of DNA at the atomic scale, DNA-associated proteins, and resulting DNA damage events and statistics, enabling a broader range of future comparisons with experiments such as those based on DNA sequencing.
PubMed: 38921049
DOI: 10.3390/biotech13020017 -
Current Issues in Molecular Biology Jun 2024In this in vivo study on hairless mice, we examined the effects of light-emitting diode (LED) treatment applied prior to ultraviolet B (UVB) irradiation. We found that...
In this in vivo study on hairless mice, we examined the effects of light-emitting diode (LED) treatment applied prior to ultraviolet B (UVB) irradiation. We found that pre-treating with LED improved skin morphological and histopathological conditions compared to those only exposed to UVB irradiation. In our study, histological evaluation of collagen and elastic fibers after LED treatment prior to UVB irradiation showed that this pretreatment significantly enhanced the quality of fibers, which were otherwise poor in density and irregularly arranged due to UV exposure alone. This suggests that LED treatment promotes collagen and elastin production, leading to improved skin properties. Additionally, we observed an increase in Claudin-1 expression and a reduction in nuclear factor-erythroid 2-related factor 2 (Nrf-2) and heme-oxygenase 1 (HO-1) expression within the LED-treated skin tissues, suggesting that LED therapy may modulate key skin barrier proteins and oxidative stress markers. These results demonstrate that pretreatment with LED light can enhance the skin's resistance to UVB-induced damage by modulating gene regulation associated with skin protection. Further investigations are needed to explore the broader biological effects of LED therapy on other tissues such as blood vessels. This study underscores the potential of LED therapy as a non-invasive approach to enhance skin repair and counteract the effects of photoaging caused by UV exposure.
PubMed: 38921009
DOI: 10.3390/cimb46060338