Selective photothermolysis in acne treatment: The impact of laser power.

BACKGROUND: Selective photothermolysis (SPT) using a 1726 nm laser has emerged as a safe and effective treatment option for acne vulgaris by targeting sebaceous glands (SG). Power output plays a crucial role in determining treatment selectivity and efficacy. AIMS: This work highlights the advantages of a higher-power laser source and outlines the limitations of lower-power laser sources and the subsequent impact on treatment. METHODS: Light transport and bioheat transfer simulations were performed to demonstrate photothermal impact on the SG and the surrounding dermis when irradiated by a high- or lower-power laser source. RESULTS: The simulations showed that a single higher-power-shorter-pulse (HPSP) selectively increases SG temperature well beyond bulk temperatures, which is desirable for SPT. Selectivity decreases linearly with power for the single lower-power-longer-pulses (LPLP) exposure. A multiple-LPLP approach elevates bulk temperatures significantly more than a single-pulse strategy, compromising selectivity. CONCLUSION: The goal of SPT is to damage SG safely and effectively by creating an intense temperature rise localized to the SG while moderately increasing the dermis temperature. This goal is mostly achieved with higher-power lasers that deliver a single HPSP. Lower-power lasers, longer pulse widths, and multi-pulse strategies result in higher bulk temperatures and lower SG selectivity, making such treatment challenging to execute while adding a higher risk of discomfort and downtime.

Selective photothermolysis with a novel 1726 nm laser beam: A safe and effective solution for acne vulgaris.

BACKGROUND: Selective photothermolysis on sebaceous glands is an effective method for treating acne vulgaris (AV); however, safety, efficacy, and discomfort hinder its utilization in clinical settings. AIMS: The primary objective is to evaluate the safety and efficacy of a novel 1726 nm laser with contact cooling to treat AV. METHODS: Seventeen patients aged 18 to 36 were enrolled and treated in this IRB-approved, single-center, open-label study. Patients received up to three facial laser sessions up to seven weeks apart. Follow-up visits happened ten days post-session and at the 4 and 12 weeks following the final session. The investigator assessed the severity of device-related adverse events (AEs). Investigator Global Assessment (IGA) and inflammatory lesion counts (ILC) were used as metrics to evaluate acne resolution and skin condition enhancement. Patients' perspectives on satisfaction and comfort using this technology were assessed using Subject Experience Questionnaires (SEQ). RESULTS: Safety assessment showed mild and transient AEs. All subjects tolerated anesthetics-free treatments well, with a mean treatment discomfort score of 4.9 ± 1.5. Compared to baseline, a statistically significant reduction in ILC (p = 0.003) of 52% to 56% is achieved four to twelve weeks following treatment. Long-term follow-ups showed progressive improvement 24 months post-treatment with a 97% reduction in ILC. SEQs revealed high subject satisfaction (71%) with psychosocial improvement three months post-treatment. CONCLUSION: The novel 1726 nm laser appears safe and effective for treating mild-to-severe acne. Acne resolution is apparent within the first month and progresses beyond the study duration.

Chemical Composition and Biological Activities of Lebanese Pentapera Plant.

BACKGROUND Due to their chemical constituents and biological properties, plants have long been used to control life-threatening diseases. The flora of Lebanon includes many plants that have already been demonstrated to have medicinal value, and other species, such as Pentapera sicula libanotica, that are yet to be characterized. The present study characterized the chemical composition, anti-oxidant, anti-inflammatory, and anti-proliferative potential of aqueous, ethanol, and methanol extracts derived from the leaves of the Lebanese Pentapera plant. MATERIAL AND METHODS High-performance liquid chromatography (HPLC) was used to determine the chemical composition. Gas chromatography (GC) coupled with mass spectrometry (MS) was applied to determine the content of essential oil. DPPH radical scavenging assay was performed to evaluate the anti-oxidant potential. The anti-inflammatory potential was assessed using quantitative real-time PCR (qRT-PCR) by measuring TNF-alpha, IL-6, and CCL4 mRNA levels, and we assessed Cox-2 and iNOS proteins levels using Western blot (WB) analysis. MTT assay was carried out to determine the anti-proliferative potential. RESULTS We identified, mainly in the alcoholic (methanol and ethanol) extracts, distinct bioactive compounds with pharmacological relevance. In parallel, with their phytochemical content, these 2 extracts showed significant anti-oxidant, anti-inflammatory and anti-proliferative capacities. CONCLUSIONS Pentapera sicula libanotica appears to be a promising pharmacological tool.

Chemopreventive effects of wild carrot oil against 7,12-dimethyl benz(a)anthracene-induced squamous cell carcinoma in mice.

CONTEXT: Daucus carota L. ssp. carota (Apiacea) is widely distributed throughout the world and has many uses in traditional medicine. OBJECTIVE: The present study investigates the chemopreventive effects of oil extract of D. carota umbels on 7,12-dimethyl benz(a)anthracene (DMBA)-induced skin cancer in mice. MATERIALS AND METHODS: D. carota oil extract (DCOE) was prepared by extracting the dried umbels with 50:50 acetone:methanol. Skin papilloma were initiated by DMBA and promoted by 12-O-tetradecanoyl phorobol-13-acetate (TPA). The extract was administered to animals via gavage (0.02 mL of 100% oil), intraperitoneal (0.3 mL of 2% oil), and topical (0.2 mL of 5, 50, and 100% oil) routes for 20 weeks. Tumor appearance, incidence, yield, and volume were compared with those of a non-treated control group. RESULTS: Topical 100% treatment delayed tumor appearance, and inhibited tumor incidence and yield by 40 and 89%, respectively. Topical 50% treatment inhibited tumor incidence and yield by 30 and 83%, respectively, whereas the 5% treatment inhibited tumor yield by 36%. Tumor volume was decreased by 99, 91, and 70% following topical treatments with 100, 50, and 5% oil, respectively. Intraperitoneal treatment inhibited tumor yield by 43%, and decreased tumor volume by 85%, whereas gavage treatment showed minimal effects on both. Intraperitoneal and topical treatment decreased infiltration and hyperplasia with an increase in the level of hyperkeratosis. CONCLUSION: These findings demonstrate that DCOE has remarkable antitumor activity against DMBA-induced skin cancer compared with non-treated animals paving the ground for further investigations.