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The Laryngoscope Apr 2024Transoral laser microsurgery represents the primary surgical modality for early laryngeal cancers with oncologic outcomes equivalent to radiotherapy. Accurate tumor...
Transoral laser microsurgery represents the primary surgical modality for early laryngeal cancers with oncologic outcomes equivalent to radiotherapy. Accurate tumor mapping and margin assessment can be difficult, however, particularly during piecemeal or ablative resections, and for tumors with a wider geographic footprint. Tumor-targeted fluorescence-guided surgery in patients with head and neck cancer has empirically improved tumor and margin identification; this case details, for the first time, a fluorescence-guided surgical resection of a T2N0M0 transglottic tumor using panitumumab-IRDye800, an epidermal growth factor receptor monoclonal antibody covalently linked to near-infrared (NIR) dye. Laryngoscope, 134:1837-1841, 2024.
Topics: Humans; Laryngeal Neoplasms; Panitumumab; Carcinoma, Squamous Cell; Microsurgery; Laser Therapy; Lasers; Glottis; Retrospective Studies; Neoplasm Staging; Indoles
PubMed: 37860983
DOI: 10.1002/lary.31078 -
Ophthalmic Surgery, Lasers & Imaging... Nov 2023This study characterizes trends in ophthalmic imaging volume and utilization in the United States among and assesses the potential impact of the COVID-19 pandemic using...
This study characterizes trends in ophthalmic imaging volume and utilization in the United States among and assesses the potential impact of the COVID-19 pandemic using data from the Centers for Medicare and Medicaid Services. Utilization of macular optical coherence tomography (OCT), optic nerve OCT, and fundus photography steadily increased from 2013 to 2020 and was not impacted by the COVID-19 pandemic. At the same time, there was minimal adoption of anterior segment OCT and a decline in the utilization of dye-based angiography. Utilization patterns may be impacted by the advent of new technologies, role of the clinician, and alignment with treatment paradigms. .
Topics: Aged; Humans; United States; Pandemics; Medicare; COVID-19; Tomography, Optical Coherence; Diagnostic Techniques, Ophthalmological
PubMed: 37855832
DOI: 10.3928/23258160-20231011-01 -
Physical Chemistry Chemical Physics :... Oct 2023Metal nanoparticles (NPs) can be employed to modify the emission level of a dye emitter by tailoring the spectral overlap of the optical gain and localized surface...
Metal nanoparticles (NPs) can be employed to modify the emission level of a dye emitter by tailoring the spectral overlap of the optical gain and localized surface plasmon resonance (LSPR). In the case of plasmonic random lasers, tuning the spectral overlap by manipulating metal NPs changes the scattering properties of the system, which is crucial in random lasers (RLs). In order to overcome this drawback, the emitter gain spectrum across the LSPR is tuned by appropriately choosing various dye emitters. A system with Au nanoislands (NIs) randomly distributed on the surface of vertically aligned ZnO nanorods on a glass substrate coated with three different dye emitters has been employed to study the metal-gain interaction as a function of spectral overlap. It is observed that the photoluminescence is quenched in the presence of Au NIs for all the three dye emitters; however, the degree of quenching is found to be directly proportional to the extent of spectral overlap of the LSPR and the fluorophore emission spectrum, with the resonantly coupled systems exhibiting higher random lasing thresholds. However, a dequenching of the emission is observed under spectrally off-resonant conditions, leading to a lower threshold RL. The effect of tailoring of the metal-gain interaction on the coherent and incoherent intensity components of RL emission is studied to elucidate the contrasting results of photoluminescence and RL emission. As the optical gain shifts away from the LSPR peak, the RL emission is dominated by the coherent intensity. The speckle-like field distributions of the RL modes couple to the plasmonic nanocavities along with a reduced absorption loss for the off-resonant case, leading to an enhanced stimulated emission. Hence, a synergy between random laser modes, plasmonic nanocavities and optimum spectral overlap has been utilized as a tool to dequench the plasmon quenched fluorophore emission.
PubMed: 37840472
DOI: 10.1039/d3cp04151d -
Journal of Fluorescence Oct 2023A benzene ring and a lactone ring combine to form the chemical coumarin. Dye lasers have made significant advances in laser technology. The coumarin molecule itself is a... (Review)
Review
A benzene ring and a lactone ring combine to form the chemical coumarin. Dye lasers have made significant advances in laser technology. The coumarin molecule itself is a non-fluorescent but it displays high fluorescence when electron-denoting substituents such as sulfonamide, benzopyrone, amine, benzothiazole, hydroxyl, methoxy are substituted at various positions. Substituted coumarin possesses the highest energy properties, photostability, and alteration in electron mobility, and therefore could be effectively used as dye lasers. These are considered some of the best fluorophores due to their outstanding photophysical and photochemical properties, which include high fluorescence quantum yields, great photostability, good functionality, and a wide spectrum range. Various inorganic materials are used in classic laser technology to generate the necessary emission. Inorganic lasers come in various types and can emit light in the electromagnetic spectrum's ultraviolet, visible, or infrared parts. Inorganic lasers have certain limitations, which is why coumarin lasers are becoming increasingly popular due to their many advantages. Compared to inorganic lasers, dye lasers offer far better tunability and cover the entire visible and near-infrared range. They only emit at very few specific wavelengths and in extremely narrow bands. The property is therefore presented in this review.
PubMed: 37837509
DOI: 10.1007/s10895-023-03459-x -
Biophysical Journal Nov 2023Techniques combining optical tweezers with fluorescence microscopy have become increasingly popular. Unfortunately, the high-power, infrared lasers used to create...
Techniques combining optical tweezers with fluorescence microscopy have become increasingly popular. Unfortunately, the high-power, infrared lasers used to create optical traps can have a deleterious effect on dye stability. Previous studies have shown that dye photobleaching is enhanced by absorption of visible fluorescence excitation plus infrared trap photons, a process that can be significantly reduced by minimizing simultaneous exposure to both light sources. Here, we report another photobleaching pathway that results from direct excitation by the trapping laser alone. Our results show that this trap-induced fluorescence loss is a two-photon absorption process, as demonstrated by a quadratic dependence on the intensity of the trapping laser. We further show that, under conditions typical of many trap-based experiments, fluorescence emission of certain fluorophores near the trap focus can drop by 90% within 1 min. We investigate how photostability is affected by the choice of dye molecule, excitation and emission wavelength, and labeled molecule. Finally, we discuss the different photobleaching pathways in combined trap-fluorescence measurements, which guide the selection of optimal dyes and conditions for more robust experimental protocols.
Topics: Optical Tweezers; Photobleaching; Photons; Fluorescent Dyes; Light
PubMed: 37828742
DOI: 10.1016/j.bpj.2023.10.006 -
Food Chemistry Mar 2024This study presents the first integrated electrochemical platform (IEP) with point-of-use and portable features for on-site determination of ponceau 4R (RP), amaranth...
This study presents the first integrated electrochemical platform (IEP) with point-of-use and portable features for on-site determination of ponceau 4R (RP), amaranth (AM), and tartrazine (TZ) in food by integrating a mass-producible Pt nanoparticles/laser-engraved graphene (Pt NPs/LEG)-based sensing chip and a reusable electrochemical miniaturized workstation. The sensing chip utilizes Pt NPs/LEG with unique architectures as electrode material and exhibits desirable analytical performance towards RP, AM, or TZ with satisfied linear range (0.25-50 μM for RP, AM, and TZ), high sensitivity (7.29 μA μM cm, 7.18 μA μM cm, and 2.02 μA μM cm for RP, AM, and TZ, respectively) and low limit of detection (50 nM, 58 nM, and 204 nM for RP, AM, and TZ, respectively). The sensing chip shows excellent selectivity, high stability, outstanding reproducibility, and acceptable mechanical stability. IEP can be implemented to test RP, AM, or TZ in real samples with satisfactory accuracy and recoveries.
Topics: Tartrazine; Graphite; Reproducibility of Results; Electrochemical Techniques; Amaranth Dye; Nanoparticles; Lasers; Electrodes
PubMed: 37806205
DOI: 10.1016/j.foodchem.2023.137611 -
Scientific Reports Oct 2023Integrated optofluidic devices have become subjects of high interest for rapid biosensor devices due to their unique ability to combine the fluidic processing of small...
Integrated optofluidic devices have become subjects of high interest for rapid biosensor devices due to their unique ability to combine the fluidic processing of small volumes of microfluidics with the analysis capabilities of photonic structures. By integrating dynamically reconfigurable optofluidic lasers on-chip, complex coupling can be eliminated while further increasing the capabilities of sensors to detect an increasing number of target biomarkers. Here, we report a polydimethylsiloxane-based device with two on-chip fluidic distributed feedback (DFB) laser cavities that are integrated with an orthogonal analyte channel for multiplexed fluorescence excitation. One DFB grating is filled with 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran dissolved in dimethyl sulfoxide. The second grating is filled with rhodamine 6G dissolved in a diluted ethylene glycol solution. We present characterization of both lasers through analysis of the lasing spectra for spectral narrowing along with a power series to observe threshold behavior. We then demonstrate simultaneous detection of two different fluorescent microbeads as a proof of concept for scalable, single biomarker analysis using on-chip optofluidic lasers.
Topics: Humans; Lasers, Dye; Feedback; Optics and Photonics; Coloring Agents; Microfluidics
PubMed: 37803034
DOI: 10.1038/s41598-023-42671-4 -
Journal of the European Academy of... Mar 2024
Topics: Humans; Lasers, Dye; Netherton Syndrome; Erythema; Low-Level Light Therapy; Treatment Outcome; Laser Therapy
PubMed: 37793828
DOI: 10.1111/jdv.19547 -
Pharmaceutics Sep 2023Microbiological control of dental pathologies presents a significant clinical challenge for dental surgeons, particularly considering drug-resistant microorganisms. To... (Review)
Review
Microbiological control of dental pathologies presents a significant clinical challenge for dental surgeons, particularly considering drug-resistant microorganisms. To address this issue, Antimicrobial Photodynamic Therapy (PDT) has emerged as an effective and complementary technique for microbial reduction. This therapy involves the application of a photosensitizer dye (PS) either topically or systemically, followed by exposure to low-power lasers with appropriate visible light wavelengths. PDT has found a valuable place in dentistry across various specialties, including surgery, periodontics, endodontics, dentistry, implantology, orthodontics, and pediatrics. In the realm of pediatric dentistry, managing microorganisms during dental treatments has become a major challenge. Considering its promising results and ease of application, Photodynamic Therapy presents an interesting alternative for clinical practice. However, it is important to note that specific protocols must be followed for each application, encompassing the type of photosensitizer, concentration, pre-irradiation time, light type, wavelength, energy, power, and mode of light delivery. Researchers have been steadily refining these protocols to facilitate PDT's integration into clinical practice. The objective of this review is to describe in which procedures and oral health problems in children PDT can be applied. In this sense, we list what the literature brings about the possibilities of applying PDT in a pediatric dentistry clinic.
PubMed: 37765303
DOI: 10.3390/pharmaceutics15092335 -
Pharmaceuticals (Basel, Switzerland) Aug 2023The potential of levosulpiride-loaded nanostructured lipid carriers (LSP-NLCs) for enhanced antidepressant and anxiolytic effects was evaluated in the current study. A...
The potential of levosulpiride-loaded nanostructured lipid carriers (LSP-NLCs) for enhanced antidepressant and anxiolytic effects was evaluated in the current study. A forced swim test (FST) and tail suspension test (TST) were carried out to determine the antidepressant effect whereas anxiolytic activity was investigated using light-dark box and open field tests. Behavioral changes were evaluated in lipopolysaccharide-induced depressed animals. The access of LSP to the brain to produce therapeutic effects was estimated qualitatively by using fluorescently labeled LSP-NLCs. The distribution of LSP-NLCs was analyzed using ex vivo imaging of major organs after oral and intraperitoneal administration. Acute toxicity studies were carried out to assess the safety of LSP-NLCs in vivo. An improved antidepressant effect of LSP-NLCs on LPS-induced depression showed an increase in swimming time (237 ± 51 s) and struggling time (226 ± 15 s) with a reduction in floating (123 ± 51 s) and immobility time (134 ± 15 s) in FST and TST. The anxiolytic activity in the light-dark box and open field tests exhibited superiority over LSP dispersion. Near-infrared images of fluorescently labeled LSP-NLCs demonstrated the presence of coumarin dye in the brain after 1 h of administration. An acute toxicity study revealed no significant changes in organ-to-body weight ratio, serum biochemistry or tissue histology of major organs. It can be concluded that nanostructured lipid carriers can efficiently deliver LSP to the brain for improved therapeutic efficacy.
PubMed: 37765028
DOI: 10.3390/ph16091220