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Journal of Cosmetic Dermatology Jul 2024Pulsed-dye lasers (PDL) are one of the standard therapies for rosacea, but alternatives are needed. (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND
Pulsed-dye lasers (PDL) are one of the standard therapies for rosacea, but alternatives are needed.
AIMS
To compare the efficacy and safety of the variable-sequenced, large-spot 532 nm KTP laser to the 595 nm PDL in treating rosacea.
MATERIALS AND METHODS
A prospective, controlled, evaluator-blinded study. Patients were treated with either a KTP or PDL with 1-3 sessions at intervals of 6-8 weeks. A follow-up visit was scheduled on Week 6 post-treatment. Clinical outcome was assessed by computer-assisted analysis and by patients and two blinded dermatologists. Pain intensity during treatment and adverse events were documented.
RESULTS
Forty-five patients (mean age 51 years) were allocated in a 2:1 ratio to either the KTP or PDL. Erythema in both treatment arms decreased significantly (p < 0.01). Clinical evaluation revealed high improvement. Mean pain intensity was significantly lower with the KTP (2.5/10) than with the PDL (4.1/10). Both lasers showed a good safety profile. Relevant purpura was only seen in the PDL group.
CONCLUSIONS
Both the variable-sequenced, large-spot KTP and the PDL demonstrated comparable efficacy in treatment of rosacea. Regarding safety, the KTP exhibited fewer post-treatment reactions. The KTP might serve as a potential alternative to PDL in the treatment of rosacea.
Topics: Humans; Rosacea; Lasers, Dye; Middle Aged; Female; Prospective Studies; Male; Adult; Lasers, Solid-State; Treatment Outcome; Low-Level Light Therapy; Erythema; Aged; Single-Blind Method; Pain Measurement; Purpura
PubMed: 38600654
DOI: 10.1111/jocd.16300 -
Nano Letters Apr 2024Hampered by their susceptibility to nucleophilic attack and chemical bleaching, electron-deficient squaraine dyes have long been considered unsuitable for biological...
Hampered by their susceptibility to nucleophilic attack and chemical bleaching, electron-deficient squaraine dyes have long been considered unsuitable for biological imaging. This study unveils a surprising twist: in aqueous environments, bleaching is not irreversible but rather a reversible spontaneous quenching process. Leveraging this new discovery, we introduce a novel deep-red squaraine probe tailored for live-cell super-resolution imaging. This probe enables single-molecule localization microscopy (SMLM) under physiological conditions without harmful additives or intense lasers and exhibits spontaneous blinking orchestrated by biological nucleophiles, such as glutathione or hydroxide anion. With a low duty cycle (∼0.1%) and high-emission rate (∼6 × 10 photons/s under 400 W/cm), the squaraine probe surpasses the benchmark Cy5 dye by 4-fold and Si-rhodamine by a factor of 1.7 times. Live-cell SMLM with the probe reveals intricate structural details of cell membranes, which demonstrates the high potential of squaraine dyes for next-generation super-resolution imaging.
PubMed: 38588010
DOI: 10.1021/acs.nanolett.4c00595 -
Transfusion Medicine and Hemotherapy :... Apr 2024Before being implemented in daily clinical routine, new production strategies for platelet concentrates (PCs) must be validated for their efficacy. Besides in vitro...
INTRODUCTION
Before being implemented in daily clinical routine, new production strategies for platelet concentrates (PCs) must be validated for their efficacy. Besides in vitro testing, the establishment of new methods requires the labeling of platelets for in vivo studies of platelets' survival and recovery. Indocyanine green (ICG) is a Food and Drug Administration-approved near-infrared (NIR) fluorescent dye for diagnostic use in vivo, suitable for non-radioactive direct cell labeling of platelets.
METHODS
Platelets from PCs in storage solutions with different plasma concentrations were labeled with ICG up to concentrations of 200 μm. Whole blood (WB) was used as an ex vivo matrix to monitor the labeling stability of ICG-labeled platelets. The impact of labeling processes was assessed by the quantification of CD62P expression and PAC-1 binding as platelet function markers. Platelet aggregation was analyzed by light transmission aggregometry. ICG-labeling efficiency and stability of platelets were determined by flow cytometry.
RESULTS
Platelets from PCs could be successfully labeled with 10 μm ICG after 1 and 4 days of storage. The best labeling efficiency of 99.8% ± 0.1% (immediately after labeling) and 81% ± 6.2% (after 24 h incubation with WB) was achieved by plasma replacement by 100% platelet additive solution for the labeling process. Since the washing process slightly impaired platelet function, ICG labeling itself did not affect platelets. Immediately after the ICG-labeling process, plasma was re-added, resulting in a recovered platelet function.
CONCLUSION
We developed a Good Manufacturing Practice compatible protocol for ICG fluorescent platelet labeling suitable for survival and recovery studies in vivo as a non-radioactive labeling alternative.
PubMed: 38584698
DOI: 10.1159/000533623 -
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 -
Dermatologic Surgery : Official... Apr 2024Warts are one of the most common benign neoplasms caused by human papillomavirus infection and often pose a therapeutic challenge.
BACKGROUND
Warts are one of the most common benign neoplasms caused by human papillomavirus infection and often pose a therapeutic challenge.
OBJECTIVE
To summarize the current evidence on the safety and efficacy of laser and energy-based devices for the treatment of cutaneous verrucae.
METHODS
A comprehensive systematic review of the literature on laser and energy-based devices for the treatment of cutaneous verrucae was performed.
RESULTS
A total of 904 unique studies were identified, of which 109 were included in this review. The most commonly used lasers as a single treatment modality for verrucae included the long-pulsed Nd:Yag (n = 20) and pulsed dye (n = 18) lasers. Other modalities included the CO2 ablative laser (n = 10), photodynamic therapy (n = 11), local hyperthermia (n = 11), microwave therapy (n = 2), and nanopulse stimulation (n = 1). Other studies combined energy-based modalities with additional treatments, such as retinoids, imiquimod, and intralesional bleomycin. Overall, such devices were generally well-tolerated, with only a mild side effect profile.
CONCLUSION
Overall, the use of laser and energy-based devices is a safe and well-tolerated option for cutaneous verrucae that is relatively less invasive than surgical interventions. Future studies using more consistent outcome assessment tools will be valuable to help clinicians develop device-specific protocols and treatment regimens to ensure replicable and effective outcomes.
Topics: Humans; Treatment Outcome; Warts; Skin; Bleomycin; Hyperthermia, Induced; Lasers, Solid-State
PubMed: 38551277
DOI: 10.1097/DSS.0000000000004069 -
Advances in Wound Care Apr 2024Pathologic scarring occurs secondary to imbalances in the cellular mechanisms of wound healing and affects millions of people annually. This review article aims to... (Review)
Review
Pathologic scarring occurs secondary to imbalances in the cellular mechanisms of wound healing and affects millions of people annually. This review article aims to provide a concise overview of the pathophysiology and management of pathologic scarring for clinicians and scientists alike. Contemporary research in the field has identified aberrations in transforming growth factor-β/small mothers against decapentaplegic (TGF-β/SMAD) signaling pathways as key drivers of pathologic scar formation; indeed, this pathway is targeted by many treatment modalities and translational investigations currently underway. Although intralesional injection of corticosteroids has been the gold standard in the treatment of pathologic scarring, studies show greater treatment efficacy with the use of combination injections such as triamcinolone/5-fluorouracil and triamcinolone/botulinum toxin. Adjunctive therapies including ablative fractional carbon dioxide/erbium-doped yttrium aluminum garnet and non-ablative pulsed-dye lasers, microneedling, and carboxytherapy have shown encouraging results in small cohort studies. Translational investigations involving the use of nanogels, RNA interference, and small molecules targeting TGF-β/SMAD pathways are also currently underway and hold promise for the future. The heterogeneous nature of hypertrophic scars and keloids poses significant challenges in formulating standardized treatment and assessment protocols, thereby limiting the conclusions that can be drawn. Rigorous clinical trials into the individual and synergistic effects of these therapies would be ideal before any definitive conclusions or evidence-based treatment recommendations can be made. Owing to the heterogeneity of the pathology and patient population, well-conducted cohort studies may be the next best option.
PubMed: 38545753
DOI: 10.1089/wound.2023.0185 -
International Journal of Molecular... Mar 2024The clinical success of dental titanium implants is profoundly linked to implant stability and osseointegration, which comprises pre-osteoblast proliferation, osteogenic...
The clinical success of dental titanium implants is profoundly linked to implant stability and osseointegration, which comprises pre-osteoblast proliferation, osteogenic differentiation, and extracellular mineralization. Because of the bio-inert nature of titanium, surface processing using subtractive or additive methods enhances osseointegration ability but limits the benefit due to accompanying surface contamination. By contrast, laser processing methods increase the roughness of the implant surface without contamination. However, the effects of laser-mediated distinct surface structures on the osteointegration level of osteoblasts are controversial. The role of a titanium surface with a laser-mediated microchannel structure in pre-osteoblast maturation remains unclear. This study aimed to elucidate the effect of laser-produced microchannels on pre-osteoblast maturation. Pre-osteoblast human embryonic palatal mesenchymal cells were seeded on a titanium plate treated with grinding (G), sandblasting with large grit and acid etching (SLA), or laser irradiation (L) for 3-18 days. The proliferation and morphology of pre-osteoblasts were evaluated using a Trypan Blue dye exclusion test and fluorescence microscopy. The mRNA expression, protein expression, and protein secretion of osteogenic differentiation markers in pre-osteoblasts were evaluated using reverse transcriptase quantitative polymerase chain reaction, a Western blot assay, and a multiplex assay, respectively. The extracellular calcium precipitation of pre-osteoblast was measured using Alizarin red S staining. Compared to G- and SLA-treated titanium surfaces, the laser-produced microchannel surfaces enhanced pre-osteoblast proliferation, the expression/secretion of osteogenic differentiation markers, and extracellular calcium precipitation. Laser-treated titanium implants may enhance the pre-osteoblast maturation process and provide extra benefits in clinical application.
Topics: Humans; Titanium; Surface Properties; Calcium; Osteogenesis; Lasers; Cell Differentiation; Antigens, Differentiation; Cell Proliferation; Osteoblasts; Osseointegration
PubMed: 38542358
DOI: 10.3390/ijms25063388 -
Lasers in Surgery and Medicine Apr 2024Port wine birthmark (PWB) is a congenital vascular malformation of the skin. Pulsed dye laser (PDL) is the "gold standard" for the treatment of PWB globally.... (Review)
Review
BACKGROUND
Port wine birthmark (PWB) is a congenital vascular malformation of the skin. Pulsed dye laser (PDL) is the "gold standard" for the treatment of PWB globally. Hematoporphyrin monomethyl ether (HMME or hemoporfin)-mediated photodynamic therapy (HMME-PDT) has emerged as the first choice for PWB treatment, particularly for young children, in many major hospitals in China during the past several decades.
AIM
To evaluate whether HMME-PDT is superior to PDL by comparing the clinical efficacies of both modalities.
METHOD
PubMed records were searched for all relevant studies of PWB treatment using PDL (1988-2023) or HMME-PDT (2007-2023). Patient characteristics and clinical efficacies were extracted. Studies with a quartile percentage clearance or similar scale were included. A mean color clearance index (CI) per study was calculated and compared among groups. An overall CI (C), with data weighted by cohort size, was used to evaluate the final efficacy for each modality.
RESULT
A total of 18 HMME-PDT studies with 3910 patients in China were eligible for inclusion in this analysis. Similarly, 40 PDL studies with 5094 patients from nine different countries were eligible for inclusion in this analysis. Over 58% of patients in the HMME-PDT studies were minors (<18 years old). A significant portion (21.3%) were young children (<3 years old). Similarly, 33.2% of patients in the PDL studies were minors. A small proportion (9.3%) was young children. The overall clearance rates for PDL were slightly, but not significantly, higher than those for HMME-PDT in cohorts with patients of all ages (C, 0.54 vs. 0.48, p = 0.733), subpopulations with only minors (C, 0.54 vs. 0.46, p = 0.714), and young children (C, 0.67 vs. 0.50, p = 0.081). Regrettably, there was a lack of long-term data on follow-up evaluations for efficacy and impact of HMME-PDT on young children in general, and central nervous system development in particular, because their blood-brain barriers have a greater permeability as compared to adults.
CONCLUSION
PDL shows overall albeit insignificantly higher clearance rates than HMME-PDT in patients of all ages; particularly statistical significance is nearly achieved in young children. Collectively, current evidence is insufficient to support HMME-PDT as the first choice of treatment of PWBs in young children given: (1) overall inferior efficacy as compared to PDL; (2) risk of off-target exposure to meningeal vasculature during the procedure; (3) administration of steriods for mitigation of side effects; -and (4) lack of long-term data on the potential impact of HMME on central nervous system development in young children.
Topics: Child; Adult; Humans; Child, Preschool; Adolescent; Photochemotherapy; Hematoporphyrins; Treatment Outcome; Port-Wine Stain; Lasers, Dye; China; Photosensitizing Agents
PubMed: 38506454
DOI: 10.1002/lsm.23779 -
Cureus Feb 2024Port-wine stains (PWSs), or port-wine birthmarks, are congenital vascular malformations that manifest as erythematous to pink patches at birth. At present, lasers are...
Port-wine stains (PWSs), or port-wine birthmarks, are congenital vascular malformations that manifest as erythematous to pink patches at birth. At present, lasers are the preferred method for treating PWSs, with pulsed dye laser (PDL) being regarded as the gold standard because of its superior efficacy compared to alternative procedures. Despite the progress made in laser therapy, a subset of patients continue to experience PWSs that cannot be resolved effectively even with PDL. A new long-pulse potassium-titanyl-phosphate (KTP) laser with a trail of sub-pulses (Derma V, Lutronic, Seoul, South Korea) is a promising treatment for PWSs resistant to PDL therapies. This is a case of a female patient with PDL-resistance PWSs that was treated successfully with a long-pulse KTP laser. Long-pulse KTP appears to be not just more effective in treating PDL-resistant PWSs but also less costly as less number of sessions are needed, with no significant side effects reported such as purpura.
PubMed: 38476792
DOI: 10.7759/cureus.53994 -
American Journal of Dentistry Feb 2024To investigate the differences between irrigant propagation and temperature changes using laser-activated irrigation (LAI) at different settings in an artificial root...
PURPOSE
To investigate the differences between irrigant propagation and temperature changes using laser-activated irrigation (LAI) at different settings in an artificial root canal model.
METHODS
Using an artificial resin root canal model, irrigant activation was achieved in 19 experimental groups with eight samples each. A 9,300 nm CO₂ laser, two diode lasers with different settings (wavelengths 455, 808, 970, and 980 nm) were compared to 2,940 nm Er:YAG laser and traditional needle irrigation. Er:YAG and CO₂ laser were activated in the pulpal chamber only, while diode lasers and needles were inserted into the main root canal. Lasers were activated for 5x 20 seconds resulting in 100 seconds of activation or rinsing for each sample. After each activation of 20 seconds, a photo was taken of the side canals and the propagation of the dye was measured with a digital measuring tool after calibration. Further, the temperature of the irrigant was reported after activation of 20 seconds and repeated 5 times. Data were checked for normality and statistically compared.
RESULTS
All lasers increased the irrigant propagation compared to conventional irrigation. Significant differences were found between groups regarding propagation and temperature (P< 0.0027). Er:YAG and CO₂ laser had similar effects on irrigant propagation in middle and apical located side-canals with specific power parameters and were superior to diode lasers and syringe irrigation. The irrigant's temperature increased significantly with the diode and CO₂ lasers.
CLINICAL SIGNIFICANCE
Diode lasers and CO₂ lasers have not been established for irrigant activation. 9,300 nm CO₂ lasers absorb well in water and were shown to introduce vapor bubble formation and streaming in water. Diode lasers are highly accepted in periodontics. The laser light is not absorbed in water but interacts with bacteria as well as soft tissues and contributes therefore to infection control. With a modified laser tip it was however possible to introduce cavitation and streaming in irrigants.
Topics: Carbon Dioxide; Lasers, Semiconductor; Proof of Concept Study; Root Canal Irrigants; Dental Pulp Cavity; Lasers, Solid-State; Water; Root Canal Preparation
PubMed: 38458982
DOI: No ID Found