scholarly journals Diagnostic Validity of Digital Imaging Fiber-Optic Transillumination (DIFOTI) and Near-Infrared Light Transillumination (NILT) for Caries in Dentine

2020 ◽  
Vol 9 (2) ◽  
pp. 420
Author(s):  
Ana Marmaneu-Menero ◽  
José Enrique Iranzo-Cortés ◽  
Teresa Almerich-Torres ◽  
José Carmelo Ortolá-Síscar ◽  
José María Montiel-Company ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Qualitative Analysis ◽  
Near Infrared ◽  
Meta Analysis ◽  
Infrared Light ◽  
X Rays ◽  
Carious Lesions ◽  
Sensitivity Specificity

The objective of the study is to analyse the available evidence for the validity of the transillumination method in the diagnosis of interproximal caries. Bibliographic searches were carried out in three data bases (PubMed, Embase, Scopus) with the key words “Transillumination AND caries”. A total of 11 studies were selected for the qualitative analysis and meta-analysis. In the qualitative analysis, both in vivo and in vitro studies were included. The gold standards were tomography, digital radiography, and clinical visual diagnosis. The meta-analysis determined the sensitivity, specificity, and area below the ROC curve relative to the transillumination method in the diagnosis of caries in dentine. Meta-analysis results obtained for transillumination gave a sensitivity value of 0.69 (confidence interval: 0.54–0.81), a specificity value of 0.89 (confidence interval: 0.61–0.98), while giving an AUC value of 0.79 (confidence interval: 0.67–0.87). Transillumination is a method offering moderate validity in the diagnosis of carious lesions in dentine, there is no strong evidence that may enable us to affirm that transillumination may fully substitute X-rays in the complementary diagnosis of carious lesions

scholarly journals Powering rotary molecular motors with low-intensity near-infrared light

2020 ◽  
Vol 6 (44) ◽  
pp. eabb6165
Author(s):  
Lukas Pfeifer ◽  
Nong V. Hoang ◽  
Maximilian Scherübl ◽  
Maxim S. Pshenichnikov ◽  
Ben L. Feringa
Keyword(s):  
Smart Materials ◽  
Molecular Motors ◽  
Near Infrared ◽  
In Vivo Studies ◽  
Infrared Light ◽  
Near Infrared Light ◽  
Two Photon ◽  
Low Intensity

Light-controlled artificial molecular machines hold tremendous potential to revolutionize molecular sciences as autonomous motion allows the design of smart materials and systems whose properties can respond, adapt, and be modified on command. One long-standing challenge toward future applicability has been the need to develop methods using low-energy, low-intensity, near-infrared light to power these nanomachines. Here, we describe a rotary molecular motor sensitized by a two-photon absorber, which efficiently operates under near-infrared light at intensities and wavelengths compatible with in vivo studies. Time-resolved spectroscopy was used to gain insight into the mechanism of energy transfer to the motor following initial two-photon excitation. Our results offer prospects toward in vitro and in vivo applications of artificial molecular motors.

H2O2/near-infrared light-responsive nanotheronostics for MRI-guided synergistic chemo/photothermal cancer therapy

Nanomedicine ◽  
2019 ◽  
Vol 14 (16) ◽  
pp. 2189-2207
Author(s):  
Yiming Yu ◽  
Li Zhang ◽  
Miao Wang ◽  
Zhe Yang ◽  
Leping Lin ◽  
...  
Keyword(s):  
Near Infrared ◽  
Tumor Model ◽  
Mri Contrast Agent ◽  
Infrared Light ◽  
Antitumor Effects ◽  
Mri Contrast ◽  
Nir Light ◽  
Nir Laser

Aim: To develop a H2O2/near-infrared (NIR) laser light-responsive nanoplatform (manganese-doped Prussian blue@polypyrrole [MnPB@PPy]) for synergistic chemo/photothermal cancer theranostics. Materials & methods: Doxorubicin (DOX) was loaded onto the surface of polypyrrole shells. The in vitro and in vivo MRI performance and anticancer effects of these nanoparticles (NPs) were evaluated. Results: The MnPB@PPy NPs could not only generate heat under NIR laser irradiation for cancer photothermal therapy but also act as an excellent MRI contrast agent. The loaded DOX could be triggered to release by both NIR light and H2O2 to enhance synergistic therapeutic efficacy. The antitumor effects were confirmed by in vitro cellular cytotoxicity assays and in vivo treatment in a xenograft tumor model. Conclusion: The designed H2O2/NIR light-responsive MnPB@PPy-DOX NPs hold great potential for future biomedical applications.

scholarly journals Microscale optoelectronic infrared-to-visible upconversion devices and their use as injectable light sources

2018 ◽  
Vol 115 (26) ◽  
pp. 6632-6637 ◽  
Author(s):  
He Ding ◽  
Lihui Lu ◽  
Zhao Shi ◽  
Dan Wang ◽  
Lizhu Li ◽  
...  
Keyword(s):  
Near Infrared ◽  
Biological Fluids ◽  
Visible Spectral Range ◽  
Infrared Light ◽  
Light Sources ◽  
Fully Integrated ◽  
Broadband Absorption ◽  
In Vivo Experiments

Optical upconversion that converts infrared light into visible light is of significant interest for broad applications in biomedicine, imaging, and displays. Conventional upconversion materials rely on nonlinear light-matter interactions, exhibit incidence-dependent efficiencies, and require high-power excitation. We report an infrared-to-visible upconversion strategy based on fully integrated microscale optoelectronic devices. These thin-film, ultraminiaturized devices realize near-infrared (∼810 nm) to visible [630 nm (red) or 590 nm (yellow)] upconversion that is linearly dependent on incoherent, low-power excitation, with a quantum yield of ∼1.5%. Additional features of this upconversion design include broadband absorption, wide-emission spectral tunability, and fast dynamics. Encapsulated, freestanding devices are transferred onto heterogeneous substrates and show desirable biocompatibilities within biological fluids and tissues. These microscale devices are implanted in behaving animals, with in vitro and in vivo experiments demonstrating their utility for optogenetic neuromodulation. This approach provides a versatile route to achieve upconversion throughout the entire visible spectral range at lower power and higher efficiency than has previously been possible.

scholarly journals Experimental and Clinical Applications of Red and Near-Infrared Photobiomodulation on Endothelial Dysfunction: A Review

Biomedicines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 274 ◽  
Author(s):  
Esteban Colombo ◽  
Antonio Signore ◽  
Stefano Aicardi ◽  
Angelina Zekiy ◽  
Anatoliy Utyuzh ◽  
...  
Keyword(s):  
Endothelial Dysfunction ◽  
Near Infrared ◽  
Disease Risk ◽  
In Vivo Studies ◽  
Infrared Light ◽  
Animal Cells ◽  
Atp Production ◽  
Main Regulator

Background: Under physiological conditions, endothelial cells are the main regulator of arterial tone homeostasis and vascular growth, sensing and transducing signals between tissue and blood. Disease risk factors can lead to their unbalanced homeostasis, known as endothelial dysfunction. Red and near-infrared light can interact with animal cells and modulate their metabolism upon interaction with mitochondria’s cytochromes, which leads to increased oxygen consumption, ATP production and ROS, as well as to regulate NO release and intracellular Ca2+ concentration. This medical subject is known as photobiomodulation (PBM). We present a review of the literature on the in vitro and in vivo effects of PBM on endothelial dysfunction. Methods: A search strategy was developed consistent with the PRISMA statement. The PubMed, Scopus, Cochrane, and Scholar electronic databases were consulted to search for in vitro and in vivo studies. Results: Fifty out of >12,000 articles were selected. Conclusions: The PBM can modulate endothelial dysfunction, improving inflammation, angiogenesis, and vasodilatation. Among the studies, 808 nm and 18 J (0.2 W, 2.05 cm2) intracoronary irradiation can prevent restenosis as well as 645 nm and 20 J (0.25 W, 2 cm2) can stimulate angiogenesis. PBM can also support hypertension cure. However, more extensive randomised controlled trials are necessary.

scholarly journals Gold-Based Nanoplataform for the Treatment of Anaplastic Thyroid Carcinoma: A Step Forward

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1242
Author(s):  
Mariana Amaral ◽  
Adília J. Charmier ◽  
Ricardo A. Afonso ◽  
José Catarino ◽  
Pedro Faísca ◽  
...  
Keyword(s):  
Thyroid Carcinoma ◽  
Cell Viability ◽  
Near Infrared ◽  
Anaplastic Thyroid Carcinoma ◽  
Infrared Light ◽  
Surface Plasmon Resonances ◽  
Plasmon Resonances ◽  
Near Future

Anaplastic thyroid carcinoma (ATC) is a very rare subtype of thyroid carcinoma and one of the most lethal malignancies. Poor prognosis is mainly associated with its undifferentiated nature, inoperability, and failing to respond to the typically used therapies for thyroid cancer. Photothermal Therapy (PTT) entails using light to increase tissues’ temperature, leading to hyperthermia-mediated cell death. Tumours are more susceptible to heat as they are unable to dissipate it. By using functionalized gold nanoparticles (AuNPs) that transform light energy into heat, it is possible to target the heat to the tumour. This study aims to formulate ATC-targeted AuNPs able to convert near-infrared light into heat, for PTT of ATC. Different AuNPs were synthetized and coated. Size, morphology, and surface plasmon resonances band were determined. The optimized coated-AuNPs were then functionalized with ligands to assess ATC’s specificity. Safety, efficacy, and selectivity were assessed in vitro. The formulations were deemed safe when not irradiated (>70% cell viability) and selective for ATC. However, when irradiated, holo-transferrin-AuNPs were the most cytotoxic (22% of cell viability). The biodistribution and safety of this formulation was assessed in vivo. Overall, this novel formulation appears to be a highly promising approach to evaluate in a very near future.

scholarly journals Generalizability of Deep Learning Models for Caries Detection in Near-Infrared Light Transillumination Images

2021 ◽  
Vol 10 (5) ◽  
pp. 961 ◽  
Author(s):  
Agnes Holtkamp ◽  
Karim Elhennawy ◽  
José E. Cejudo Grano de Oro ◽  
Joachim Krois ◽  
Sebastian Paris ◽  
...  
Keyword(s):  
Deep Learning ◽  
Near Infrared ◽  
Infrared Light ◽  
Learning Models ◽  
Near Infrared Light ◽  
In Vivo Models ◽  
Lower Accuracy ◽  
Caries Lesions

Objectives: The present study aimed to train deep convolutional neural networks (CNNs) to detect caries lesions on Near-Infrared Light Transillumination (NILT) imagery obtained either in vitro or in vivo and to assess the models’ generalizability. Methods: In vitro, 226 extracted posterior permanent human teeth were mounted in a diagnostic model in a dummy head. Then, NILT images were generated (DIAGNOcam, KaVo, Biberach), and images were segmented tooth-wise. In vivo, 1319 teeth from 56 patients were obtained and segmented similarly. Proximal caries lesions were annotated pixel-wise by three experienced dentists, reviewed by a fourth dentist, and then transformed into binary labels. We trained ResNet classification models on both in vivo and in vitro datasets and used 10-fold cross-validation for estimating the performance and generalizability of the models. We used GradCAM to increase explainability. Results: The tooth-level prevalence of caries lesions was 41% in vitro and 49% in vivo, respectively. Models trained and tested on in vivo data performed significantly better (mean ± SD accuracy: 0.78 ± 0.04) than those trained and tested on in vitro data (accuracy: 0.64 ± 0.15; p < 0.05). When tested in vitro, the models trained in vivo showed significantly lower accuracy (0.70 ± 0.01; p < 0.01). Similarly, when tested in vivo, models trained in vitro showed significantly lower accuracy (0.61 ± 0.04; p < 0.05). In both cases, this was due to decreases in sensitivity (by −27% for models trained in vivo and −10% for models trained in vitro). Conclusions: Using in vitro setups for generating NILT imagery and training CNNs comes with low accuracy and generalizability. Clinical significance: Studies employing in vitro imagery for developing deep learning models should be critically appraised for their generalizability. Applicable deep learning models for assessing NILT imagery should be trained on in vivo data.

scholarly journals Upconversion superballs for programmable photoactivation of therapeutics

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhen Zhang ◽  
Muthu Kumara Gnanasammandhan Jayakumar ◽  
Xiang Zheng ◽  
Swati Shikha ◽  
Yi Zhang ◽  
...  
Keyword(s):  
Near Infrared ◽  
Endosomal Escape ◽  
Infrared Light ◽  
Deep Tissue ◽  
Sequential Activation ◽  
Uv Visible ◽  
Favorable Conditions ◽  
Multiple Molecules

Abstract Upconversion nanoparticles (UCNPs) are the preferred choice for deep-tissue photoactivation, owing to their unique capability of converting deep tissue-penetrating near-infrared light to UV/visible light for photoactivation. Programmed photoactivation of multiple molecules is critical for controlling many biological processes. However, syntheses of such UCNPs require epitaxial growth of multiple shells on the core nanocrystals and are highly complex/time-consuming. To overcome this bottleneck, we have modularly assembled two distinct UCNPs which can individually be excited by 980/808 nm light, but not both. These orthogonal photoactivable UCNPs superballs are used for programmed photoactivation of multiple therapeutic processes for enhanced efficacy. These include sequential activation of endosomal escape through photochemical-internalization for enhanced cellular uptake, followed by photocontrolled gene knockdown of superoxide dismutase-1 to increase sensitivity to reactive oxygen species and finally, photodynamic therapy under these favorable conditions. Such programmed activation translated to significantly higher therapeutic efficacy in vitro and in vivo in comparison to conventional, non-programmed activation.

scholarly journals Photothermal ablation of murine melanomas by Fe3O4 nanoparticle clusters

2021 ◽  
Author(s):  
Xue Wang ◽  
Lili Xuan ◽  
Ying Pan
Keyword(s):  
Near Infrared ◽  
Underlying Mechanism ◽  
Local Heat ◽  
In Vivo Studies ◽  
Infrared Light ◽  
Microscopy Imaging ◽  
Development Of Resistance ◽  
Nanoparticle Clusters

Melanoma is one of the deadliest forms of cancer, for which therapeutic regimens are usually limited by the development of resistance. Here, we fabricated the Fe3O4 nanoparticle clusters (NPCs) that have drawn widespread attention and investigated their role in the treatment of melanoma by photothermal therapy (PTT). Transmission electron microscopy imaging shows that our synthesized NPCs are spherically shaped with an averaged diameter of 329.2 nm. They are highly absorptive at the near-infrared 808 nm wavelength and efficient at converting light into local heat. In vitro experiments using light-field microscopy and MTT assay showed that Fe3O4 NPCs, in conjunction with near-infrared irradiation, effectively ablated A375 melanoma cells by inducing overt apoptosis. Consistently, in vivo studies using BALB/c mice found that intratumoral administration of Fe3O4 NPCs and concomitant in situ exposure to near-infrared light significantly inhibited growth of implanted tumor xenografts. Finally, we revealed, by experimental approaches including semi-quantitative PCR, western blot and immunohistochemistry, the heat shock protein HSP70 to be upregulated in response to PTT, suggesting this chaperone protein could be a plausible underlying mechanism for the observed therapeutic outcome. Altogether, our results highlight the promise of Fe3O4 NPCs as a new PTT option to treat melanoma.

scholarly journals Self-Assembly Iron Oxide Nanoclusters for Photothermal-Mediated Synergistic Chemo/Chemodynamic Therapy

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Xiang Li ◽  
Zhen Wang ◽  
Mian Ma ◽  
Zhouqing Chen ◽  
Xiang-long Tang ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Self Assembly ◽  
Near Infrared ◽  
Light Irradiation ◽  
Infrared Light ◽  
Photothermal Effect ◽  
Photothermal Conversion ◽  
Assembly Method

Background and Purpose. Although chemodynamic therapy (CDT) is promising for cancer treatment, its clinical application is still limited because of unresolved issues. In this study, an efficient CDT agent for synergistic chemo/CDT therapy mediated by the photothermal effect was developed by an iron oxide self-assembly method. Methods. Superparamagnetic iron oxide nanoclusters (SPIOCs) were located within the core, which resulted in high photothermal conversion and outstanding generation of reactive oxygen species (ROS). The shell consisted of a human serum albumin- (HSA-) paclitaxel (PTX) layer, which extended the blood circulation time and ensured the effectiveness of the chemotherapy. Arg-Gly-Asp peptides (RGD) were linked to the naked cysteine moieties in HSA to promote the specific targeting of human glioma U87 cells by αvβ3 integrins. Continuous near-infrared light irradiation triggered and promoted the synergistic chemo/CDT therapy through the photothermal effect. Results. Our SPIOCs@HSA-RGD nanoplatform showed well biocompatibility and could target glioma specifically. Photothermal conversion and ROS burst were detected after continuous 808 nm light irradiation, and a significant antitumor effect was achieved. Conclusion. Experimental in vitro and in vivo evaluations showed that our photothermal-mediated chemo/CDT therapy could efficiently inhibit tumor growth and is therefore promising for cancer therapy.

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