- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Repression of melanoma tumor in vitro and in vivo by photothermal effect of carbon xerogel nanoparticles
摘要： A N U S C RIP T including photothermal therapy (PTT) of cancer. Since conventional strategies of cancer treatment have not responded to this serious disease, development of efficient alternative and promising strategies is highly desirable. In this study, carbon xerogel nanoparticles (CX-NPs) were synthesized as a novel photothermal nanomaterial and activated upon laser light of 808-nm wavelength for cancer phototherapy application. The synthesized CX-NPs had a spherical shape with a size of about 16 nm that showed nice photothermal conversion ability. Upon light irradiation with a power density of 1.0 W cm-2 for 15 min, a temperature increment occurred. A concentration-dependent cytotoxicity was also obtained for CX-NPs toward the C540 (B16/F10) cell line upon light irradiation, while CX-NPs presented biocompatibility in the mice model in dark. Photothermal property of CX-NPs efficiently led to reduction in the cell viability. A low-dose of CX-NPs was also applied in PTT of a melanoma tumor-bearing animal model. Based on tumor histopathological evaluations and volume change measurements in mice, a very good control of tumor situations after PTT by CX-NPs was attained. The findings revealed that CX-NPs is a good and novel photoabsorber for PTT of cancer.
关键词： Nanomedicine,Diode laser,Photothermal therapy,Carbon nanostructure,Cancer
更新于2025-09-19 17:15:36
-
Thermometry in a Gas Discharge Cell of an Optical Wavelength Calibrator
摘要： Temperature and pressure in a sealed Ar cell of an optical wavelength calibrator are measured using diode laser spectroscopy. The values of the thermodynamic parameters allowed determination of the fluctuations of the shift of the argon line at 811.5 nm. The expected fluctuation amplitude appears lower than ±15 MHz. The result obtained indicates the applicability of the studied calibrator as an optical reference and the correctness of previous measurements of pressure shift coefficients of the 811.5 nm argon line.
关键词： thermometry,diode-laser spectroscopy,optical calibrator,low pressure RF discharge,spectral line pressure shift,argon
更新于2025-09-19 17:15:36
-
Multi-Objective Optimization of High Power Diode Laser Surface Hardening Process of AISI 410 by means of RSM and Desirability Approach
摘要： In this research, laser surface hardening of AISI 410 was carried out by a high power diode laser based on Response Surface Method (RSM). Laser power, scanning speed, and focal plane position were evaluated as input process changeable while geometry dimensions of hardened zone (i.e., Depth and width of hardness), maximum hardness, Microhardness deviation (MHD) from base material in depth, and ferrite phase percentage in the microstructure were evaluated as process output Results. The effect of input parameters on the response variations were studied by statistical investigation. Results indicated that by increasing the laser power and decreasing other parameters, higher surface hardness with significant penetration, and least ferrite percentage would be reached by means of the desirability function approach. By using experimental tests, validation of optimized results was performed. In this research in the optimum conditions, the maximum hardness, maximum depth of hardness and minimum ferrite percentage were achieved 670 Vickers, 2.2 mm and 0.45%, respectively.
关键词： Laser Surface Hardening,High Power Diode Laser,Design of Experiments,Laser Materials Processing,Optimization
更新于2025-09-19 17:13:59
-
Comparison of A 1940 nm Thulium-Doped Fiber Laser and A 1470 nm Diode Laser for Cutting Efficacy and Hemostasis in A Pig Model of Spleen Surgery
摘要： Partial and total splenectomies are associated with a high risk of substantial blood loss. Lasers operating at wavelengths strongly absorbed by water have the potential to improve hemostasis and cut while providing a narrow zone of thermal damage. The aim of this study is to compare a thulium-doped fiber laser (TDFL) emitting a wavelength of 1940 nm and a diode laser (DL) operating at 1470 nm for spleen surgery in a pig model. A partial splenectomy and spleen incisions were made in 12 animals using the two laser devices. The hemostasis was evaluated visually during surgeries. Post-mortem and histopathological evaluations were done on days 0, 7, and 14 following surgery. Neither TDFL nor DL caused bleeding on day 0 or delayed bleeding. On day 14, pale streaks at the site of incision were slightly wider after cutting with DL than with TDFL. Histological analysis revealed a carbonized zone with exudation and a deeper zone of thermal tissue damage on day 0. The width of the thermal changes was 655.26 ± 107.70 μm for TDFL and 1413.37 ± 111.85 μm for DL. On day 7, a proliferation of fibroblasts and splenocytes was visible, as well as a formation of multinucleated giant cells adjacent to the residues of carbonization. The zone of thermal damage was broader for DL (1157.5 ± 262.77 μm) than for TDFL (682.22 ± 116.58 μm). On day 14, cutting sites were filled with connective and granulation tissues with the residues of carbonization. The zone of thermal damage was narrower for TDFL (761.65 ± 34.3 μm) than for DL (1609.82 ± 202.22 μm). Thus, both lasers are efficient in spleen surgery, providing good hemostasis. However, TDFL produces a narrower zone of thermal damage, which suggests its better efficiency for spleen surgery, especially when performing more precise procedures.
关键词： thulium-doped fiber laser (1940 nm),pig model of spleen surgery,diode laser (1470 nm),thermal damage zone,partial splenectomy,hemostasis
更新于2025-09-19 17:13:59
-
Ex vivo and animal study of the blue diode laser, Tm fiber laser, and their combination for laparoscopic partial nephrectomy
摘要： Background and Objectives: To evaluate the feasibility of using a novel blue diode laser (blue laser), a thulium fiber laser (Tm laser), and their combination as a directed‐energy surgical tool in laparoscopic partial nephrectomy (LPN). Study Design/Materials and Methods: The blue laser emitting at 442 nm, the Tm laser emitting at 1,940 nm wavelengths, and the combination of them were tested. First, cutting and coagulative abilities of the lasers were characterized ex vivo on porcine kidney in air and CO2. Histological staining was performed to assess the efficiency of ablation and coagulation. Next, experimental LPN was performed on a porcine model at zero ischemia. Upper and lower segments of both kidneys were resected. Total operation time and resection time were measured; bleeding and carbonization were evaluated. Results: Ex vivo data show that laser‐induced ablation and coagulation processes do not differ substantially between CO2 and air environments. Histological analysis of ex vivo incisions demonstrates that the blue laser produced deep ablation with relatively narrow coagulation zone, whereas Tm laser was less efficient in terms of ablation but possessed excellent coagulative properties. Experimental LPN revealed that the blue laser provided fast cutting with minimal carbonization, whereas Tm laser induced slow cutting with strong carbonization. The combination of the blue and Tm lasers provided the most promising results demonstrating the highest resection rate, almost carbonization free resection surface and clinically acceptable hemostasis enabling LPN without the need for vessel clamping. Conclusions: The blue laser can be efficiently utilized in LPN. Furthermore, the combination of the blue and Tm lasers into a single modality may be beneficial for further development of successful laser‐assisted LPN.
关键词： Tm fiber laser,laparoscopic partial nephrectomy,porcine model,blue diode laser
更新于2025-09-19 17:13:59
-
Short-term surgical outcomes and histomorphological evaluation of thermal injury following palatoplasty performed with diode laser or air plasma device in dogs with brachycephalic airway obstructive syndrome
摘要： Brachycephalic obstructive airway syndrome (BOAS) is a common disorder presenting enlarged soft palate, stenotic nares and abnormal turbinate growth. Surgical correction of BOAS abnormalities with caudal palatoplasty is an elective therapy. This prospective study aimed to compare the effect of an air plasma device and diode laser in dogs undergoing palatoplasty. Outcome measures were as follows: (1) intra-operative and immediate post-operative complications; (2) evaluation of thermal injury in histological tissue sections of the excised soft palate. Twenty dogs with enlarged soft palates underwent palatoplasty, using an air plasma device (n = 10) and diode laser (n = 10). Soft palate specimens underwent masked histopathological analysis to assess post-operative thermal injury. In this pilot study, no differences were observed in surgical times; all dogs were discharged 24 h after surgery and had stable respiration. In the air plasma group, post-operative bleeding occurred in two cases and revision surgery was performed. No difference in thermal injury was observed using the two devices (P > 0.05). The air-plasma device was a viable surgical option for palatoplasty in dogs with BOAS.
关键词： Brachycephalic syndrome,Air plasma device,Diode laser,Dog
更新于2025-09-19 17:13:59
-
Application of the least square method for processing the signal obtained by the tuneable diode laser absorption spectroscopy method in the range 4860a??4880a??cm <sup>a??1</sup> for the problem of measuring <sup>13</sup> CO <sub/>2</sub> content in exhaled air
摘要： The 1st, 2nd and 3rd order least square method (LSM-1, LSM-2 and LSM-3) is applied to smooth the experimental absorption signal of 13CO2 and 12CO2 obtained by the tuneable diode laser absorption spectroscopy method in the 4860–4880 cm?1 frequency range of a tuneable diode laser. It has been shown clearly that using LSM-2 with a filter window N ~ 100 allows the 13CO2 content in exhaled air to be measured at an error level of 0.28%, which meets breathing tests requirements.
关键词： gas analysis,biomedical analysis,carbon dioxide,tuneable diode laser absorption spectroscopy (TDLAS)
更新于2025-09-19 17:13:59
-
Characterization and applications of auto-locked vacuum-sealed diode lasers for precision metrology
摘要： We demonstrate the performance characteristics of a new class of vacuum-sealed, autolocking diode laser systems and their applications to precision metrology. The laser is based on adaptations of a design that uses optical feedback from an interference filter and it includes a vacuum-sealed cavity, an interchangeable base-plate, and an autolocking digital controller. A change of the base-plate allows operation at desired wavelengths in the visible and near infrared spectral range, whereas the autolocking ability allows the laser to be tuned and frequency stabilized with respect to atomic, molecular, and solid-state resonances without human intervention using a variety of control algorithms programmed into the same controller. We characterize the frequency stability of this laser system based on the Allan deviation (ADEV) of the beat note and of the lock signal. We find that the ADEV floor of 2 × 10?12 and short-term linewidth of ～200 kHz are strongly influenced by current noise and vacuum sealing. Reducing the current noise and cavity pressure decreases the ADEV floor and increases the averaging time at which the floor occurs, which is a signature of long-term stability. We also show that evacuating the cavity to ～1 Torr reduces the range of the correction signal of the feedback loop by approximately one order of magnitude, thereby increasing the lock range of the controller. The long-term stability allows the laser to be incorporated into a commercial gravimeter for accurate measurements of gravitational acceleration at the level of a few parts-per-billion, which are comparable to values obtained with an iodine-stabilized He–Ne laser. The autolocking and pattern-matching features of the controller allow the laser to be tuned and stabilized with respect to a temperature tunable transmission spectrum of a fiber-Bragg grating. This capability may be suitable for the development of a differential absorption LIDAR transmitter that can generate data at both on-line and off-line lock points using a single laser.
关键词： precision metrology,autolocking,frequency stability,LIDAR,vacuum-sealed,diode laser,gravimeter
更新于2025-09-19 17:13:59
-
800??nm diode laser does not display longa??term benefit for hair removal in Becker's nevus: A retrospective analysis of 24 cases
摘要： Becker’s nevus is manifested by either ipsilateral or bilateral pigmented patch with or without hypertrichosis. Although other regimens, including oral antiandrogen and topical glycolic acid, are available, lasers are the most widely used therapeutic regimen. The clinical outcomes of laser therapy for Becker’s nevus vary greatly with studies, skin color, body site and number of treatment session. Previous studies showed that a diode laser reduced hair density by 47-80% in Fitzpatrick skin type V-dominated cohort, whether diode laser can effectively remove hair in Becker’s nevus in Chinese is unknown. Moreover, whether diode laser exhibits long-term benefit for hair removal in Becker’s nevus also remains to be determined. Here, we retrospectively analyze the efficacy and safety of 800 nm diode laser for hair removal in Backer’s nevus in Chinese.
关键词： Becker’s nevus,hypertrichosis,hair removal,diode laser,recurrence
更新于2025-09-19 17:13:59
-
Diode laser transscleral cyclophotocoagulation for uveitis-glaucoma-hyphema syndrome
摘要： Rationale: To report a case of diode laser transscleral cyclophotocoagulation (DLTSC) for uveitis-glaucoma-hyphema syndrome (UGH). Patient concerns: The patient developed UGH on the right eye (OD) after vitrectomy and intraocular lens (IOL) implantation. Diagnoses: Best corrected visual acuity (BCVA) was HM/50 cm, intraocular pressure (IOP) was 51.3 mm Hg on the OD. He was found to have 3+ anterior chamber cells. A B-scan ultrasound showed vitreous opacity. Ultrasound biomicroscopy (UBM) showed the chafing between the IOL and the posterior surface of the iris. Thus, he was diagnosed as UGH on the OD. Interventions: The patient was worried about the complications for removal of the IOL, a DLTSC approach was performed. Outcomes: BCVA was 20/40 on the OD, IOP was 12 mm Hg on the OD. There were no anterior chamber inflammation and no vitreous opacity. UBM showed there was no contact between IOL and the posterior surface of the iris, the fundus of the eye was clearly visible. Lessons: UGH syndrome is a severe complication of cataract extraction. IOL extraction has been the traditional approach to treatment. DLTSC can be an option when the IOL is slightly tilted.
关键词： acrylic single-piece intraocular lens,uveitis-glaucoma-hyphema (UGH) syndrome,diode laser transscleral cyclophotocoagulation,case report
更新于2025-09-19 17:13:59