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Skin Research and Technology : Official... Aug 2023The Flash-lamp pulsed dye laser (FPDL) is nowadays considered the most precise laser currently on the market for treating superficial vascular lesions. In this study, we...
INTRODUCTION
The Flash-lamp pulsed dye laser (FPDL) is nowadays considered the most precise laser currently on the market for treating superficial vascular lesions. In this study, we gathered data from 10 years of experience regarding dye laser treatment of patients presenting vascular malformations such as telangiectasia, rhinophyma, port-wine stain, cherry and spider angioma and vascular tumours.
METHODS
Subjects were enrolled from 2013 to 2023 based on the vascular anomalies they presented. They underwent different treatment sessions with the FPDL device.
RESULTS
The age-range distribution by vascular anomaly confirmed that haemangiomas are typical in children while rhinophyma is a condition very common in older adults. A difference in sex distribution showed that pathologies such as telangiectasias typically affect women whereas rhinophyma is more frequent in men. Most of the treatments interested the face area but no permanent side effects were registered.
CONCLUSIONS
Our 10 years of experience with FPDL demonstrated good results in a wide range of applications for the treatment of different vascular anomalies. The absence of long-term side effects and bearable pain during the treatment makes it a valuable solution for the resolution of benign tumours also in very young patients.
Topics: Female; Humans; Male; Lasers, Dye; Retrospective Studies; Rhinophyma; Hemangioma; Vascular Malformations
PubMed: 37632184
DOI: 10.1111/srt.13427 -
Polymers Jul 2023Due to the increased application of lasers in different fields (industry, medicine, etc.), there is a growing need for new laser sources with good beam quality and...
Due to the increased application of lasers in different fields (industry, medicine, etc.), there is a growing need for new laser sources with good beam quality and variable emission wavelength. At the same time, for environmental reasons, the obtaining of novel eco-friendly active optical materials, such as those based on the deoxyribonucleic acid (DNA) biopolymer, with optimal light emission properties, is of high interest. The results obtained in this study of the temporal dependence of the transmittance and of the light emission in thin films of DNA-CTMA-Rhodamine 610 (at different Rhodamine concentrations) (DNA-CTMA-Rh610), when they are illuminated with continuous wave laser light at 532 nm (frequently used in the optical pumping of dye lasers), are presented and discussed. The transmittance results obtained for thin film samples are compared to those obtained for the DNA-CTMA-Rh610 solutions in butanol, from which the films have been made, and also with those obtained for Rh610 solutions in butanol with the same concentrations. The investigation was performed in order to assess the influence of the DNA-CTMA and of the green laser light at 532 nm wavelength on relevant chromophore properties such as light transmission and fluorescence emission. The results obtained revealed that the DNA-CTMA matrix has an active influence on the Rhodamine 610 emission, in the whole range of concentrations of the investigated samples.
PubMed: 37514494
DOI: 10.3390/polym15143105 -
Optics Express Jul 2023Continuous-wave laser emission is challenging to obtain in organic lasers, whether in the solid or liquid form, a limitation caused by long-lived triplet states and by...
Continuous-wave laser emission is challenging to obtain in organic lasers, whether in the solid or liquid form, a limitation caused by long-lived triplet states and by thermal effects. In liquid dye lasers, both issues can be fixed by rapidly flowing the dye, which is technically complex and prevents those lasers to be further miniaturized or easily integrated. Here we address the issue of the maximal pulsewidth that can be obtained in liquid dye lasers in the absence of any dye flow, in a compact and cost-effective diode-pumped laser system. Pulses as long as 80 μs have been obtained, thanks to the combination of a hemispherical resonator design, almost insensitive to thermal-lens effects, and an intentional mismatch between pump and cavity spatial modes. The limitation in pulse duration is shown to be entirely due to thermal blooming, and more specifically to diffraction losses brought by the spherical aberration of the thermal lens.
PubMed: 37475434
DOI: 10.1364/OE.480590 -
BioRxiv : the Preprint Server For... Jul 2023The small size and flexibility of G protein-coupled receptors (GPCRs) have long posed a significant challenge to determining their structures for research and...
The small size and flexibility of G protein-coupled receptors (GPCRs) have long posed a significant challenge to determining their structures for research and therapeutic applications. Single particle cryogenic electron microscopy (cryoEM) is often out of reach due to the small size of the receptor without a signaling partner. Crystallization of GPCRs in lipidic cubic phase (LCP) often results in crystals that may be too small and difficult to analyze using X-ray microcrystallography at synchrotron sources or even serial femtosecond crystallography at X-ray free electron lasers. Here, we determine the previously unknown structure of the human vasopressin 1B receptor (V1BR) using microcrystal electron diffraction (MicroED). To achieve this, we grew V1BR microcrystals in LCP and transferred the material directly onto electron microscopy grids. The protein was labeled with a fluorescent dye prior to crystallization to locate the microcrystals using cryogenic fluorescence microscopy, and then the surrounding material was removed using a plasma-focused ion beam to thin the sample to a thickness amenable to MicroED. MicroED data from 14 crystalline lamellae were used to determine the 3.2 Å structure of the receptor in the crystallographic space group 1. These results demonstrate the use of MicroED to determine previously unknown GPCR structures that, despite significant effort, were not tractable by other methods.
PubMed: 37461729
DOI: 10.1101/2023.07.05.547888 -
The Journal of Dermatological Treatment Dec 2023Although pulsed dye laser (PDL) is the treatment of choice for port-wine stains (PWS), clinical resistance to PDL has been observed in 20-30% of cases. Several... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Although pulsed dye laser (PDL) is the treatment of choice for port-wine stains (PWS), clinical resistance to PDL has been observed in 20-30% of cases. Several alternative treatment modalities have been introduced; however, there is still a lack of definite recommendations regarding the optimal treatment for difficult-to-treat PWS.
OBJECTIVE
We aimed to systematically review and analyze the comparative effectiveness among treatments for problematic PWS.
METHODS & MATERIALS
We systematically searched for comparative studies assessing treatments for patients with difficult-to-treat PWS through relevant biomedical databases until August 2022. A Network Meta-Analysis (NMA) was conducted to estimate the odds ratio (OR) for all pairwise comparisons. The primary outcome is the improvement of lesions of more than 25%.
RESULTS
Of the 2498 studies identified, six treatments from five studies were available for NMA. Compared with 585 nm short-pulsed dye laser (SPDL), intense pulsed light (IPL) was the most effective in clearing lesions (OR 11.81, 95% CI 2.15 to 64.89, very low confidence rating), followed by 585 nm long-pulsed dye laser (LPDL) (OR 9.95, 95% CI 1.75 to 56.62, very low confidence rating). The 1064 nm NdYAG, 532 nm NdYAG, and LPDL >585 nm exhibited potential superiority over SPDL 585 nm, although statistical significance was not observed.
CONCLUSIONS
IPL and 585 nm LPDL are likely to be more effective than 585 nm SPDL for treating difficult-to-treat PWS. Well-designed clinical trials are warranted to confirm our findings.
Topics: Humans; Lasers, Dye; Low-Level Light Therapy; Network Meta-Analysis; Port-Wine Stain; Treatment Outcome
PubMed: 37424384
DOI: 10.1080/09546634.2023.2231582 -
The Journal of Dermatological Treatment Dec 2023Onychopapilloma is a rare benign nail tumor affecting the distal matrix and the nail bed. Currently, the only available treatment is surgical resection, which has a...
Onychopapilloma is a rare benign nail tumor affecting the distal matrix and the nail bed. Currently, the only available treatment is surgical resection, which has a recurrence rate of 20% and may lead to various complications. Here we report a new method to treat onychopapilloma with pulsed dye laser (PDL). We retrospectively analyzed 13 cases and evaluated disease classification, dermoscopic examination, laser treatment parameters, photographs before and after treatment, and treatment outcome. The site distribution of onychopapilloma was consistent with previous reports. PDL treatment was performed with 595 nm laser, with 1.5 ms pulse duration, spot diameter 3-5 mm, and 11.5-13.5 J/cm fluence. Irradiation covered the telangiectatic area up to the edge of the nail folds, with the terminal response of purpura occurrence. The overall effective rate was 77%; the effective rates for erythronychia, leukonychia, and melanonychia were 88%, 67%, and 50%, respectively. PDL treatment for onychopapilloma provides an alternative to traditional surgery with comparable effectiveness but much less risk for complications.
Topics: Humans; Lasers, Dye; Retrospective Studies; Treatment Outcome; Purpura; Low-Level Light Therapy; Nail Diseases
PubMed: 37260138
DOI: 10.1080/09546634.2023.2213363 -
Journal of Burn Care & Research :... Mar 2024Currently, most burn models for preclinical testing are on animals. For obvious ethical, anatomical, and physiological reasons, these models could be replaced with...
Currently, most burn models for preclinical testing are on animals. For obvious ethical, anatomical, and physiological reasons, these models could be replaced with optimized ex vivo systems. The creation of a burn model on human skin using a pulsed dye laser could represent a relevant model for preclinical research. Six samples of excess human abdominal skin were obtained within one hour after surgery. Burn injuries were induced on small samples of cleaned skin using a pulsed dye laser on skin samples, at varying fluences, pulse numbers and illumination duration. In total, 70 burn injuries were performed on skin ex vivo before being histologically and dermato-pathologically analyzed. Irradiated burned skin samples were classified with a specified code representing burn degrees. Then, a selection of samples was inspected after 14 and 21 days to assess their capacity to heal spontaneously and re-epithelize. We determined the parameters of a pulsed dye laser inducing first, second, and third degree burns on human skin and with fixed parameters, especially superficial and deep second degree burns. After 21 days with the ex vivo model, neo-epidermis was formed. Our results showed that this simple, rapid, user-independent process creates reproducible and uniform burns of different, predictable degrees that are close to clinical reality. Human skin ex vivo models can be an alternative to and complete animal experimentation, particularly for preclinical large screening. This model could be used to foster the testing of new treatments on standardized degrees of burn injuries and thus improve therapeutic strategies.
Topics: Animals; Humans; Burns; Skin; Epidermis; Lasers, Dye; Wound Healing
PubMed: 37202124
DOI: 10.1093/jbcr/irad071 -
Actas Dermo-sifiliograficas Mar 2024
Topics: Humans; Lasers, Dye; Erythema; Dermatomyositis; Patients
PubMed: 36115383
DOI: 10.1016/j.ad.2022.08.020