Lasers in Medical Science最新文献

Photodynamic therapy (PDT) is an alternative to cancer treatment, demonstrating selectivity and significant cytotoxicity on malignant tissues. Such therapy involves two nontoxic components: photosensitizer (PS) and non-ionizing radiation. In optimal dosage combinations, PDT causes cellular and tissue effects by oxygen-dependent processes, leading tumor cells to regulated cell death pathways. Regulated necrosis, called necroptosis, can be triggered by PDT and is characterized by caspase-8 inhibition and RIPK1, RIPK3, and MLKL activities, leading to plasma membrane pores formation with subsequent cellular content release into the extracellular space. For this review, studies accessed by PubMed describing the relation between necroptosis and PDT were summarized. The results showed that PDT can trigger necroptosis mechanisms in different tumor cells. Moreover, a mix of different cell death types can co-occur. It is also important to highlight that necroptosis triggered by PDT is related to damage-associated molecular patterns (DAMPs) release, involving immunogenic cell death and vaccination. The cell death response is directly related to the photosensitizer chemical characteristics, concentration, incubation time, cellular location, and irradiation parameters. The synergism among all cell death types is an excellent advantage for avowing tumor resistance mechanisms and developing new solutions.

Different types of photosensitizers (PSs) have different dynamics and intensities of accumulation, depending on the type of tumor or different areas within the same tumor. This determines the effectiveness of fluorescence diagnostics and photodynamic therapy (PDT). This paper studies the processes of 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) and chlorin e6 (Ce6) accumulation in the central and border zones of a tumor after combined administration of two PSs into the patient's body. Fluorescence diagnostic methods have shown that sublingual administration of 5-ALA leads to the more intense accumulation of PpIX in a tumor compared to oral administration. Differences have been identified in the dynamics of 5-ALA-induced PpIX and Ce6 accumulation in the central and border zones of the tumor, as well as normal tissues. Ce6 accumulates mainly in the central zone of the tumor while PpIX accumulates in the border zone of the tumor. All patients with combined PDT experienced complete therapeutic pathomorphosis and relapse-free observation.

The complexity of the gastrointestinal system plays a crucial role in coordinating essential processes such as digestion, nutrient absorption, and waste elimination. inflammatory bowel diseases (IBD) pose significant treatment challenges due to their complex aetiology and varied symptoms. Conventional therapeutic approaches often involve pharmacological interventions, which may have side effects and limited efficacy. Photobiomodulation (PBM), also known as low-level light therapy, has emerged as a promising therapeutic or adjunctive alternative in the treatment of intestinal diseases. The search was conducted in the MEDLINE database via PubMed, SCOPUS, covering the period from 1990 to 2024. A total of 72 studies were selected, of which 9 focused on inflammatory bowel diseases IBD, including ulcerative colitis (UC) and Crohn's disease (CD). Among these studies, 1 was clinical protocol while eight experimental. The results showed that PBM has a significant positive effect in IBD studies in rats, with reduction of intestinal inflammation, improvement of mucosal integrity, and modulation of the immune response. However, no clinical studies were found necessary to obtain results and establish effective and safe treatment protocols. Nevertheless, PBM holds potential as a non-invasive and complementary therapeutic approach for managing IBD, offering new perspectives for the treatment of chronic intestinal diseases. Therefore, this brief review emphasizes the need to transition from preclinical research to clinical research on this topic and highlights the scarcity of clinical studies.

The bone volume preservation after dental extraction is challenging in case of implant rehabilitation for functional and aesthetics results. Photobiomodulation (or LLLT) is used in medicine for its properties of accelerating the healing process. The aim of the systematic review was to determine if the use of photobiomodulation had an impact on implant stability and on alveolar bone healing, either in quality or in quantity. A systematic review following the PRISMA guidelines was conducted on the databases PubMed, Science Direct, Scopus and Google Scholar. The review was registered on Prospero under the number CRD42023467581. 414 articles were screened, of which 12 were selected for the review. In 10 of the 12 articles, LLLT seemed to show a positive impact on bone healing and implant stability. Regarding alveolar preservation, 6 out of 8 studies found statistically significant results. Regarding implant stability, 3 out of the 4 articles found a statistically significant impact of photobiomodulation versus control group. Despite the great heterogeneity of the studies, some LLLT protocols seemed consensual: the use of a Ga-Al-As laser with an emission over 800 nm with a continuous emission consisting of 3 to 4 sessions each with a duration of 4 to 5 min, on a sole application point. The use of photobiomodulation seemed to inhance the alveolar bone healing after a dental extraction, and the implant stability in case of immediate extraction-implantation. Further randomized controlled trials with a placebo group seem mandatory to corroborate the results.

The purpose of this review was to evaluate the effect of Photobiomodulation (PBM) in managing shoulder and neck pain and disability. A literature search was conducted using the PubMed and ScienceDirect/EMBASE databases. The keywords used were "Low-level laser therapy", "photobiomodulation", "LASER", combined with "shoulder" or "neck". Only clinical studies written in English, Portuguese, Spanish, Italian, French, and German, were included. The review included 36 studies applying PBM therapy to alleviate pain or disability in patients with shoulder and neck conditions. Of these, 12 studies focused on neck conditions, and 24 studies addressed shoulder conditions, with one study concurrently examining both areas. This review on PBM therapy for shoulder and neck conditions shows promising results, particularly in pain relief and functional improvements, with infrared wavelengths being the most commonly used. Subacromial Impingement Syndrome (SAIS) and Myofascial Pain Syndrome (MPS) were the most frequently studied conditions. However, chronic and complex conditions like cervical osteoarthritis and post-stroke shoulder pain were less frequently represented, indicating a research gap. PBM was found to be a safe and non-invasive therapeutic option. Despite positive outcomes, variability in PBM protocols remains a challenge. Further standardized trials are needed to confirm its effectiveness across diverse conditions. This review updates current knowledge, highlights key findings, and provides direction for future research and clinical applications.

This study assessed the impact of low-level laser irradiation on the viability and proliferation of human periodontal ligament stem cells (hPDLSCs) cultivated on polylactic acid (PLA) scaffolds. hPDLSCs were obtained, characterized, and grown on the surface of PLA films produced via the solvent casting technique. The study involved two groups: the control group, which was not exposed to radiation, and the laser group, which was irradiated with a diode laser (InGaAIP) with a power of 30 mW, a wavelength of 660 nm, and a single dose of 1 J/cm² emitted continuously. Cell viability was assessed 24 and 48 hours after irradiation using the Alamar blue and Live/Dead assays. Flow cytometry was used to assess cell cycle events, and scanning electron microscopy (SEM) was used to evaluate the interaction between cells and the biomaterial. The results revealed a statistically significant increase in cell metabolic activity in the laser group compared with the control group at 24 hours (p <0.05) and 48 hours (p <0.001), as indicated by the Alamar blue assay. The Live/Dead assay also revealed a greater density of viable cells in the laser group. The cell cycle analysis revealed a significant increase in the number of cells in the proliferative phase (G2/M) in the laser group compared with the control group (p <0.001). The SEM images demonstrated that the irradiated group had a greater concentration of cells while still maintaining their cell shape and projections. This study demonstrated that photobiomodulation can increase the viability and proliferation of periodontal stem cells cultured on PLA scaffolds, suggesting the potential of this protocol for future studies on periodontal tissue engineering.

Multiple mode procedures (MMP) of fractional CO₂ laser provide higher efficacy and shorter downtime in treating acne scars, compared to traditional fractional CO₂ laser therapy. This study aims to evaluate the effectiveness and safety of modified MMP integrated with fractional microneedle radiofrequency (FMR), ultra-pulse CO₂ laser and fractional CO₂ laser in treating acne scars. A retrospective analysis of 162 acne scar patients treated with MMP or modified MMP was conducted. Acne scars were evaluated using the Echelle d'Evaluation Clinique des Cicatrices d'Acné (ECCA) grading scale, modified Manchester Scar Scale (mMSS), and Global Assessment Scale (GAS). Baseline variables were balanced with propensity score matching (PSM) to improve the comparability of treatment effectiveness and safety between groups. Among 162 patients with facial acne scars, 68 were treated with modified MMP and 94 with traditional MMP. After PSM, both groups had 55 patients with comparable baseline characteristics (P > 0.05). The ECCA score decreased more significantly in the modified MMP group (60%±11%) than in the MMP group (45%±16.6%, P < 0.001). The modified MMP group also had higher mMSS color score (2.6 ± 0.7 vs. 2.1 ± 0.9, P = 0.005), greater reduction in pore size and skin laxity (P < 0.001), shorter postoperative erythema duration (22.2 ± 4.0 vs. 31.3 ± 3.7 days, P < 0.001), but higher pain scores (Visual Analogue Scale, VAS: 6.7 ± 1.6 vs. 3.8 ± 0.8, P < 0.001). Modified MMP is more effective than traditional MMP in treating acne scars, especially for patients with large pores and skin laxity.

Photobiomodulation (PBM) occurs when a cell is exposed to low energy intensities. A novel central venous port (CVP) with light-emitting diodes (LEDs) that emits red light with a wavelength of 680 nm via wireless energy transmission technology has been established. This comparative in vitro study examined whether PBM can reduce the growth of methicillin-resistant Staphylococcus aureus (MRSA), a common cause of central venous (CV) infections, in vitro. In this comparative in vitro study, the red light with a wavelength of 680 nm was used to irradiate an MRSA suspension in phosphate-buffered saline for 7.5, 15, 30, or 60 min in a 3.5 cm Petri dish with an area of 8.5 cm2. The total energy was 85 J at 7.5 min, 170 J at 15 min, 340 J at 30 min, and 680 J at 60 min. Six dishes for each time and 6 temperature-controlled samples were prepared. Each sample was incubated overnight at 37℃. The Shapiro-wilk test was used to determine whether the data were normally distributed. The numbers of colonies were counted and compared using one-factor ANOVA and Bonferroni's post-hoc test. The mean numbers of colonies in the control group were 60.3, where the numbers of colonies in the irradiated group were 51.4 at 7.5 min, 53.5 at 15 min, 44.6 at 30 min, 34.3 at 60 min. The mean number of colonies in the 60 min irradiated group differed significantly from that in the control, 7.5 min, and 15 min groups. The Bonferroni's post-hoc test showed significant difference in the number of colonies between control vs. 30 min control vs. 60 min, 7.5 min vs. 60 min, 15 min vs. 60 min. PBM with 680 nm LEDs on MRSA for 340 J at 30 min and 680 J at 60 min inhibited the growth of cell colonies. These findings support the use of photobiomodulation in Central venous port to prevent CV access port-Blood stream infection.

Our previous study first reported the efficacy of FURL using 365 μm fibers with holmium: yttrium aluminum garnet (Ho: YAG) laser lithotripsy. This study evaluates the 16-week safety of this procedure. A prospective cohort study was conducted, and the clinical characteristics of patients who underwent FURL using 365 μm fibers with Ho: YAG laser were retrospectively collected. Descriptive statistics were reported, and logistic regression analysis was conducted to identify risk factors influencing the stone-free rate (SFR). Infection-related laboratory parameters, including white blood cell count (WBC), procalcitonin (PCT), and C-reactive protein (CRP), were collected. Regression analysis was conducted to identify risk factors for the development of urosepsis post-surgery. Additionally, a 16-week follow-up was conducted in outpatient clinics, and kidney function was assessed. A total of 274 patients participated in this study. The 4-week stone-free rate (SFR) following FURL with 365 μm fibers of Ho: YAG laser was significantly associated with stone size and composition. No severe complications were observed following FURL procedures. There were no significant differences in white blood cell count (WBC), C-reactive protein (CRP), and procalcitonin (PCT) in peripheral blood before and after FURL procedures. Urosepsis was diagnosed in 1.82% of patients. Preoperative white blood cell count (WBC) in urine and preoperative urine culture results were identified as significant risk factors. Kidney function remained stable at 4 and 16 weeks following FURL. This prospective cohort study demonstrated the high safety of FURL with 365 μm fibers of Ho: YAG laser, as infection-related parameters during the perioperative period showed no significant differences, and kidney function remained stable throughout the 16-week follow-up.