Journal of lasers in medical sciences最新文献

Introduction: Time-dependent effects of laser radiation have been investigated by researchers. An understanding of the molecular mechanism of the time course effect of the laser needs molecular assessment and function evaluation of the related genes. In the present study, the importance of repetition of treatment after 4 weeks and gene expression alteration after 7 days of laser radiation versus one day on the human skin was evaluated via protein-protein interaction (PPI) network analysis and gene ontology enrichment. Methods: The differentially expressed genes (DEGs) were extracted from Gene Expression Omnibus (GEO) and assessed via PPI network analysis. The critical DEGs were enriched via gene ontology. The related biological processes and biochemical pathways were retrieved from "GO-Biological process" and "Kyoto Encyclopedia of Genes and Genomes" (KEGG) respectively. Results: The repetition of laser therapy after 4 weeks of the first treatment did not have a significant effect on treatment efficacy. Sixty-three significant DEGs and six classes of biological terms discriminated the samples seven days after the treatment from individuals one day after the treatment. The studied DEGs were organized into two clusters with certain functions. Conclusion: Based on the findings after laser therapy, several days are required to complete the critical processes such as DNA biosynthesis and skin cornification.

Introduction: There are some ways to examine heat transfer in tumor tissue, which is an important issue in bioengineering. One of these ways uses the bioheat equation, proposed by Pennes, in a continuous medium. Another one uses a porous medium to model heat transfer in living tissues. The objective of this paper was to study an approach to modelling the temperature distribution and tumour ablation in brain tissue and compare results to Pennes' approach. Methods: This approach presents and uses a porous medium as the tissue instead of a continuous medium. In addition, the two approaches (simulation in continuous and porous medium) are compared in terms of temperature simulation and amount of cell ablation. The density, heat conduction factor, and blood perfusion rate are considered functions of temperature. Results: In these approaches, after an 85-second treatment, the temperature increases to about 90°C. The temperature increase of the porous medium is relatively the same as that of the continuous medium and for this reason, the amount of cancerous cells that are ablated in a porous medium is approximately the same as that in a continuous medium. The volume of cell ablation is about 6500 mm³ for two ideas. In addition, the degree of damage, computed from the Arrhenius integral method, and the ablated volume of the tumour endorse equality at the end of treatment. According to the results, similar to the continuous approach, the porous approach predicts the temperature and amount of volume of damaged cells. Conclusion: Therefore, it is possible to use the porous approach instead of the Pennes approach for tumour treatment.

Introduction: Photodynamic therapy (PDT) is applied as an efficient method for preventing the progress of cancers. Light and a photosensitive compound which is known as photosensitizer (PS) are the main parts of PDT. In the present study, molecular events after using PDT in the presence of a super lethal dose of a PS were assessed via protein-protein interaction (PPI) analysis. Methods: Data were extracted from Gene Expression Omnibus (GEO). The gene expression profiles of the treated human Sk-Cha1 cells via PDT were compared with the control cells. Expressed change analysis and PPI network analysis were administrated via Cytoscape software v 3.7.2 to find the critical differentially expressed genes (DEGs). Regulatory relationships between the central DEGs were evaluated and the highlighted genes were identified. Results: The significant amounts of gene expression values were grouped and a few DEGs characterized by tremendously expressed values were identified. EGFR, CANX, HSPA5, MYC, JUN, ITGB1, APP, and CDH1 were highlighted as hub-bottleneck DEGs. EGFR, CDH1, and JUN appeared as a set of SEGs, which play a crucial role in response to PDT in the treated Sk-Cha1 cells. Conclusion: In conclusion, regulatory relationships between EGFR, CDH1, and JUN, which have an effect on the regulation of cellular survival, differentiation, and proliferation, were highlighted in the present investigation.

Introduction: Temporomandibular disorders (TMDs) are the most prevalent non-dental origin orofacial pain conditions affecting the temporomandibular joints (TMJs) and/or orofacial muscles. Photobiomodulation therapy (PBMT) is a conservative way to improve function and reduce symptoms in TMD patients. This systematic review was conducted to update evidence about the effects of PBMT on pain intensity, TMJ movements, electromyography (EMG) activity, pressure pain threshold (PPT), and TMJ sound in patients with TMDs. Methods: A systematic literature search was conducted in Web of Science, PubMed/Medline, and Scopus databases using appropriate keywords and specific strategies from January 2000 to September 2022. Data extraction was done based on the inclusion/exclusion criteria. Results: A total of 40 studies were included. All included studies except one provided information on pain intensity; 27 studies showed a reduction in pain intensity in PBMT groups compared to control groups. Seven out of 15 studies, which reported maximum mouth opening (MMO), showed a greater MMO in PBMT groups than in placebo groups. In addition, the figures for passive maximum mouth opening (PMMO) and active maximum mouth opening (AMMO) in all the studies reporting PMMO and AMMO were higher in PBMT groups. In eight out of ten studies, lateral movement (LM) was greater in PBMT groups. Moreover, in three studies out of four, protrusive movement (PM) was reported to be greater in the PBMT group. Four out of nine studies showed a greater PPT in the PBMT group. Reduced TMJ sounds in the PBMT group were reported in two out of five studies. In addition, in most studies, no difference in EMG activity was detected between the two groups. Conclusion: This updated systematic review showed the promising effects of PBMT on the alleviation of pain and improvement in MMO. Using the infrared diode laser with a wavelength ranging between 780-980 nm, an energy density of<100 J/ cm², and an output power of≤500 mW for at least six sessions of treatment seems to be a promising option for treating mentioned TMDs signs and symptoms based on the previously reported findings.

Introduction: This study investigated the photobiomodulation effect of an 810-nm diode laser in adjunction with topical anesthesia on pain perception during infiltration anesthesia of primary maxillary molars in children. Methods: This double-blind randomized controlled clinical trial was conducted on 64 children (aged 5-9 years) requiring extraction or stainless steel crown for their primary maxillary molars. The patients were randomly allocated into two groups (n=32) of laser and control. In the laser group, the injection site (buccal and palatal mucosa) was irradiated with an 810-nm laser (200 mW, 5.2 J/cm²) after 20% benzocaine topical anesthetic application, while the control group received a placebo laser following topical anesthesia. The pain intensity experienced by children during needle insertion into the buccal and palatal mucosa was determined using a visual analog scale (VAS) and modified behavioral pain scale (MBPS). Results: According to the results of the VAS and MBPS, no significant difference was detected in pain scores between the laser and control groups neither in the buccal nor in the palatal mucosa (P>0.05). Conclusion: Photobiomodulation therapy with an 810-nm laser with the current setting adjunct to topical anesthesia did not promote significant additional effects on the pain intensity.

Introduction: Keloid scars and hypertrophic scars are more commonly seen after surgeries, suture placements, or other skin damages. Scars can be treated using a variety of methods, including topical compounds, surgery, and lasers. The aim of this study is to evaluate the effects of plasma exeresis on the treatment of keloid scars. Methods: This experimental study was conducted on patients with keloid scars, defined as a treatment-resistant subtype of scars with extension beyond the primary skin defect and cauliflower appearance, in different parts of the body. The patients were treated with 2-to-3-session plasma exeresis. Scars were examined based on the Vancouver scar scale (VSS) before and 5 months after the treatment. Results: A total number of 24 scars were enrolled in this study. The number of patients was 16. There was a decrease in the mean thickness of keloids from 2.20 to 0.54 (P=0.000). The mean pigmentation and pliability scores decreased from 1.54 and 2.16 to 0.375 and 0.541, respectively (P=0.001, 000). There was a significant reduction in the keloid scar vascularity score from 1.666 to 0.541 (P=0.000). There was a decrease from 0.708 to 0.00 (P=0.004) in the mean itchiness score. After the intervention, the mean pain score was 0.000, compared to 0.7500 before the intervention (P=0.003). There was a decrease in the total score from 8.958 to 2.000 (P=0.000). Conclusion: The plasma exeresis procedure is effective in destroying small keloid scars. Furthermore, results in less itching and pain, as well as no significant complications or recurrences.

Introduction: Here, we assess the therapeutic effects of photobiomodulation (PBM) and curcumin (CUR)-loaded superparamagnetic iron oxide nanoparticles (SPIONs), alone or together, on the maturation step of a type 1 diabetes (DM1) rat wound model. Methods: Full-thickness wounds were inflicted in 36 rats with diabetes mellitus (DM) induced by the administration of streptozotocin (STZ). The rats were randomly allocated to four groups. Group one was untreated (control); group two received CUR; group 3 received PBM (890 nm, 80 Hz, 0.2 J/cm²); group 4 received a combination of PBM plus CUR. On days 0, 4, 7, and 15, we measured microbial flora, wound closure fraction, tensile strength, and stereological analysis. Results: All treatment groups showed a substantial escalation in the wound closure rate, a substantial reduction in the count of methicillin-resistant Staphylococcus aureus (MRSA), a substantial improvement in wound strength, a substantially improvement in stereological parameters compared to the control group, however, the PBM+CUR group was superior to the other treatment groups (all, P≤0.05). Conclusion: All treatment groups showed significantly improved wound healing in the DM1 rat model. However, the PBM+CUR group was superior to the other treatment groups and the control group in terms of wound strength and stereological parameters.

Introduction: A variety of laser treatments have been applied in numerous medical fields. In dentistry, laser treatments are used for caries, root canals, and periodontal disease, as well as surgical resection. Numerous reports have recently been published on the use of lasers for bone regeneration. If laser irradiation is found to promote the activation of bone metabolism, it might also be effective for periodontal treatment, peri-implantitis, and bone regeneration. Therefore, the present in vitro study aimed to elucidate the mechanisms underlying the effects of erbium-doped yttrium aluminum garnet (Er: YAG) laser irradiation on the bone using osteoblast-like cells. Methods: Osteoblast-like Saos 2 cells (5.0×10⁴ cells) were seeded in 24-well plates. 24 hours after being seeded, the cells were subjected to 0.3 W, 0.6 W, and 2.0 W Er: YAG laser irradiation and then allowed to recover for 48 hours. The expression levels of bone metabolism-related factors alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteoprotegerin (OPG) were then evaluated using reverse transcription-quantitative polymerase chain reaction and western blot analyses. Results: Saos 2 cells subjected to Er: YAG laser irradiation at 0.3 W, 0.6 W, and 2.0 W showed normal growth. When the Er: YAG laser irradiation and control groups were compared after 48 hours, increases were observed in ALP, BSP, and OPG gene and protein expression in the 2.0 W group. Similar results were obtained in the western blot analysis. Conclusion: These findings suggest that the Er: YAG laser irradiation of osteoblast-like cells is effective for activating bone metabolism factors.

Introduction: Complete healing of a gingivectomy wound usually takes between one and two months. To speed up this process, different topical medications have been reported. In addition, there are different studies assessing the efficacy of low-level laser therapy (LLLT) in terms of wound healing and pain relief subsequent to gingivectomy, yielding inconsistent outcomes. In the present study, we systematically reviewed the existing evidence in the literature to resolve the given conflicts. Methods: We searched for the studies published from inception to 1 April 2023 in Embase, PubMed, and Scopus databases without language limitation by the use of appropriate keywords. We included randomized or non-randomized clinical trial studies that appraised the efficacy of LLLT in pain reduction and wound healing in adult patients who underwent gingivectomy. We pooled the continuous data concerning the pain visual analogue scale and the healing index extracted from the individual studies to provide a standardized mean difference (SMD) with a 95% confidence interval (CI), using a random-effects model. Results: Out of 188 sources initially captured from the database search, six studies were ultimately included. Regarding wound healing, the LLLT group exhibited a significantly higher mean value of the healing index compared to the control group on days 3 (SMD, 0.93; 95% CI, 0.39 to 1.47) and 7 (SMD, 1.03; 95% CI, 0.49 to 1.57) post-surgery. Also, significant differences were noted in the postoperative pain reduction between the two groups on days 3 (SMD, -2.00; 95% CI, -2.48 to -1.51) and 7 (SMD, -2.44; 95% CI, -4.66 to -0.22) post-surgery. Conclusion: According to the present systematic review, LLLT could potentially be an efficient adjunctive treatment after gingivectomy for wound healing acceleration and patient pain alleviation.