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Lasers in Medical Science Dec 2023Reducing treatment time is one of the most important trends in modern dentistry. This study aimed to compare the micro-leakage around the resin sealants when using both...
Reducing treatment time is one of the most important trends in modern dentistry. This study aimed to compare the micro-leakage around the resin sealants when using both high and conventional intensity light-curing systems. The study sample consisted of 30 extracted human maxillary premolar teeth that were divided into two equal groups according to the light-curing system used: Group 1, High-Intensity Light-Curing System and Group 2, Conventional Light-Curing System. Light-curing by Woodpecker I-LED device with two intensities (high and conventional) has been used. All teeth were subjected to 500 cycles of thermocycling. Then, a methylene blue dye microleakage test was performed, and the teeth were sectioned longitudinally and studied under a stereo microscope. The mean of micro-leakage in the high-intensity group (1.33 ± 1.29) was less than in the conventional intensity group (1.63 ± 1.29) without any statistically significant differences (p = 0.320). The high-intensity light-curing system mode may be a good and acceptable alternative to conventional intensity light-curing system mode in polymerization of pits and fissure sealants.
Topics: Humans; Composite Resins; Pit and Fissure Sealants; Curing Lights, Dental; Light-Curing of Dental Adhesives; Bicuspid; Dental Leakage
PubMed: 38159193
DOI: 10.1007/s10103-023-03963-3 -
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 -
The Analyst Oct 2023We report a fiber optofluidic laser (FOFL) using an RhB-doped ionic liquid (BmimPF) as the gain medium and explore its application for large dynamic range highly...
We report a fiber optofluidic laser (FOFL) using an RhB-doped ionic liquid (BmimPF) as the gain medium and explore its application for large dynamic range highly sensitive pH sensing. Due to the high -factor of the FOFL and the unique merits of BmimPF, lasing emission presents a threshold of only 0.61 μJ mm. Particularly, lasing emission behaviors are strongly dependent on the pH value of the gain medium, , in the pH range 4.28-6.37, the lasing central wavelength blue-shifts monotonically with a sensitivity as high as 5.02 nm per pH unit, which we attribute to the conversion of the cationic form of RhB to the zwitterionic form caused by the deprotonation of the COOH group. Under alkaline conditions (pH 7.20-11.17), the lasing emission intensity exhibits a significant decrease and the corresponding lasing central wavelength is also blue-shifted due to the solvent effect. The sensitivity based on the wavelength shift is 3.03 nm per pH unit, which is 4-fold higher than that of fluorescence-based sensing, while the sensitivity based on the variation of the lasing emission intensity is almost three orders of magnitude higher than that of fluorescence-based sensing. Our work presents a novel dual sensing paradigm in response to different pH conditions, which can greatly improve the reliability and discrimination of pH sensing.
PubMed: 37668015
DOI: 10.1039/d3an01156a -
Biomaterial Investigations in Dentistry 2024To evaluate the penetration of a dye in root dentin after activation with different laser wavelengths.
OBJECTIVE
To evaluate the penetration of a dye in root dentin after activation with different laser wavelengths.
MATERIALS
Palatal roots of 38 human molars were enlarged and disinfected. Irrigation activation was performed with an Er:YAG laser: @50 mJ, 15 Hz (Er:YAG); a 9.3 µm CO laser: @40% power (CO); diode lasers 455 nm/970 nm: @0.8 W, 15 Hz (D455, D970) and 808/980 nm: @1 W (D808, D980) and compared to positive control: etching with 35% HPO (POS); negative control: water (NEG) and conventional needle irrigation: NaOCl and ethylenediaminetetraacetic acid (EDTA) (CONV). Methylene blue solution was introduced in the canal and laser-activated or left untouched for 100 s before the roots were dried and cut into horizontal slices. Dye penetration was automatically calculated by color recognition of two samples per root third ( = 8 per group in each coronal, middle and apical root thirds). The presence and absence of a smear layer was checked in two additional samples of the negative and positive control under scanning electron microscopy (SEM).
RESULTS
Full-depth infiltration was not achieved in any group. Dye penetration in CONV was significantly less than in Er:YAG, CO POS, D455, D970, D808 and similar to NEG and D980 when results of different root thirds were pooled.
CONCLUSION
Laser activation using certain parameters enhanced dye penetration compared to conventional needle irrigation with NaOCl and EDTA (CONV).
PubMed: 38645926
DOI: 10.2340/biid.v11.40311 -
Angewandte Chemie (International Ed. in... Jun 2024New photostable and bright supramolecular complexes based on cucurbit[7]uril (CB7) host and diketopyrrolopyrole (DPP) guest dyes having two positively charged...
New photostable and bright supramolecular complexes based on cucurbit[7]uril (CB7) host and diketopyrrolopyrole (DPP) guest dyes having two positively charged 4-(trimethylammonio)phenyl groups were prepared; with spectra (H2O, abs. / emission max. 480 / 550 nm; e ~ 19 000, tfl > 4 ns), strong binding with hosts (~560 nM Kd) and a linker affording fluorescence detection of bioconjugates with antibody and nanobody. Combination of protein-functionalized DPP dye with CB7 improves photostability and affords up to 12-fold emission gain. Two-color confocal and stimulated emission depletion (STED) microscopy with 595 nm or 655 nm STED depletion lasers shows that the presence of CB7 not only leads to improved brightness and image quality, but also results in DPP becoming cell-permeable.
PubMed: 38881490
DOI: 10.1002/anie.202410217 -
International Journal of Molecular... Dec 2023The hybridization of inorganic and organic components is a promising strategy to build functional materials. Among several functions, luminescence is an important...
The hybridization of inorganic and organic components is a promising strategy to build functional materials. Among several functions, luminescence is an important function which should be considered for practical usage. Inorganic-organic hybrid luminescent materials have been investigated as phosphors, sensors, and lasers. Organic luminescent centers such as dye molecules have often been hybridized with inorganic matrices. Polyoxometalate anions (POMs) are effective inorganic luminescent centers due to their luminescent properties and structural designability. However, most luminescent POM components are limited to lanthanide-based POMs. In this report, a photoluminescent inorganic-organic hybrid crystal based on a non-lanthanide POM was successfully synthesized as a single crystal. Anderson-type hexamolybdochromate ([CrMoO(OH)], CrMo) anion exhibiting emission derived from Cr was utilized with -dodecylammonium ([CHNH], CNH) surfactant cation to obtain a photoluminescent hybrid crystal. The grown single crystal of CNH-CrMo comprised a distinct layered structure consisting of inorganic CrMo layers and interdigitated CNH layers. In the CrMo layers, the CrMo anions were associated with water molecules by hydrogen bonding to form a densely packed two-dimensional network. Steady-state and time-resolved photoluminescence spectroscopy revealed that the CNH-CrMo hybrid crystal exhibited characteristic emission from the CrMo anion. Preliminary lasing properties were also observed for CNH-CrMo, which shows the possibility of using the CNH-CrMo hybrid crystal as an inorganic-organic hybrid laser.
Topics: Surface-Active Agents; Pulmonary Surfactants; Anions; Lipoproteins; Lanthanoid Series Elements; Lasers; Polyelectrolytes; Osteomyelitis
PubMed: 38203515
DOI: 10.3390/ijms25010345 -
Lasers in Surgery and Medicine Jul 2024Knowledge of the physical effects of pulsed dye laser (PDL) treatment of psoriatic lesions is essential in unraveling the remedial mechanisms of this treatment and hence...
OBJECTIVES
Knowledge of the physical effects of pulsed dye laser (PDL) treatment of psoriatic lesions is essential in unraveling the remedial mechanisms of this treatment and hence also in maximizing in its disease-modifying potential. Therefore, the main objective of this study was to provide estimates of these physical effects (for laser wavelengths of 585 and 595 nm), with the aim of identifying pathogenic processes that may be affected by these conditions.
METHODS
We modeled the laser light propagation and subsequent photothermal heating by numerically solving the transient diffusion and heat equations simultaneously. To this end, we used the finite element method in conjunction with an image-derived psoriatic lesion morphology (which was defined by segmenting blood vessels from a confocal microscopy image of a fluorescently labeled section of a 3 mm punch biopsy of a psoriatic lesion). The resulting predictions of the generated temperature field within the lesion were then used to assess the possibility of stalling or arresting some suspected pathogenic processes.
RESULTS
According to our results, it is conceivable that perivascular nerves are thermally denatured, as almost all locations that reach 60°C were found to be within 18 µm (at 585 nm) and 11 µm (at 595 nm) of a blood vessel wall. Furthermore, activation of TRPV1 and TRPV2 channels in perivascular neuronal and immune cells is highly likely, since a critical temperature of 43°C is generated at locations within up to 350 µm of a vessel wall (at both wavelengths) and sustained for up to 700 ms (at 585 nm) and 40 ms (at 595 nm), while a critical temperature of 52°C is reached by locations within 80 µm (at 585 nm) and 30 µm (at 595 nm) of a vessel wall and sustained for up to 100 ms (at 585 nm) and 30 ms (at 595 nm). Finally, we found that the blood vessel coagulation-inducing temperature of 70°C is sustained in the vascular epithelium for up to 19 and 5 ms at 585 and 595 nm, respectively, rendering partial or total loss of vascular functionality a distinct possibility.
CONCLUSIONS
The presented approach constitutes a useful tool to provide realistic estimates of the photothermal effects of PDL treatment of psoriatic plaques (as well as other selective photothermolysis-based treatments), yielding information that is essential in guiding future experimental studies toward unraveling the remedial mechanisms of these treatments.
Topics: Humans; Lasers, Dye; Psoriasis; Microscopy, Confocal; Finite Element Analysis; Models, Biological
PubMed: 38576388
DOI: 10.1002/lsm.23781 -
Journal of Gastrointestinal Surgery :... Sep 2023
Topics: Animals; Swine; Laser Speckle Contrast Imaging; Stomach; Perfusion; Lasers; Laser-Doppler Flowmetry; Regional Blood Flow
PubMed: 37227609
DOI: 10.1007/s11605-023-05708-7 -
Advanced Materials (Deerfield Beach,... Apr 2024Blue phase liquid crystal (BPLC) lasers have potential applications in displays, sensors, and anti-counterfeiting fields owing to their outstanding optical properties....
Blue phase liquid crystal (BPLC) lasers have potential applications in displays, sensors, and anti-counterfeiting fields owing to their outstanding optical properties. However, there remain challenges on lasing below 0 °C, which significantly limits the potential application of BPLC lasers in low-temperature environments. In this work, BPLC lasing below 0 °C is realized for the first time in a super-wide temperature range of -180-240 °C using a well-designed fully-polymerized BPLC system with a narrow line width of 0.0881 nm and a low lasing threshold of 37 nJ pulse. This fully-polymerized BPLC both effectively avoids low-temperature random crystallization and has excellent compatibility with dye molecules that significantly widen the lasing temperature range below 0 °C. Besides, the variations of laser peak and threshold are also revealed below 0 °C, that is, redshifted laser wavelength and increased threshold value with decreasing temperature, which contribute to a blue-shifted laser signal and a U-shaped lasing threshold in -180-240 °C. These unique laser behaviors can be ascribed to the temperature-dependent anisotropically microstructural deformation of the BP lattice. This work not only opens a door to the development of low-temperature BPLC lasers but also sets out important insights in the design of novel organic optical devices.
PubMed: 38270274
DOI: 10.1002/adma.202308439 -
Journal Der Deutschen Dermatologischen... Oct 2023
Topics: Humans; Port-Wine Stain; Lasers, Dye; Laser Therapy; Health Services; Germany; Treatment Outcome
PubMed: 37550854
DOI: 10.1111/ddg.15181