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1.
Lasers Med Sci ; 39(1): 178, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990392

RESUMO

To evaluate the visual outcome and astigmatic correction following trifocal intraocular lens (IOL) implantation using the modified femtosecond laser-assisted arcuate keratotomy (FSAK) in Chinese cataract patients with low astigmatism. This retrospective study included consecutive cataract patients with regular corneal astigmatism ranging from 0.75 to 1.5 D who underwent FSAK combined with the trifocal IOL implantation between November 2020 and September 2022. Monocular uncorrected distance visual acuity, uncorrected intermediate visual acuity, uncorrected near visual acuity, and refractive data were collected at the 3-month follow-up. The pre- and post-operative high-order aberrations (HOAs) were recorded. The variation in astigmatism was analyzed using Alpins vector analysis. A total of 27 eyes from 23 patients were analyzed. The monocular uncorrected distance visual acuity (UDVA) (5 m) at the 3-month follow-up was 0.04 ± 0.09 logarithm of the minimum angle of resolution (logMAR), which was significantly improved compared with the preoperative value of 0.95 ± 0.51 logMAR (P <.001). The corneal astigmatism was significantly reduced from 1.24 ± 0.42 D to 0.49 ± 0.34 D (P <.001). The target-induced astigmatism (TIA) was 1.25 ± 0.43 D, the surgically induced astigmatism (SIA) was 1.16 ± 0.52 D, and the difference vector (DV) was 0.5 ± 0.34 D. The magnitude of error (ME) (difference between SIA and TIA) was -0.1 ± 0.41 D, and the correction index (CI) (ratio of SIA to TIA) was 0.93 ± 0.36. The angle of error was 3.92° ± 16.90°. Total HOA was reduced from 0.89 ± 1.11 to 0.41 ± 0.55 (P = 0.184), and the corneal HOA was lowered from 0.17 ± 0.18 to 0.10 ± 0.10 (P = 0.129). Implantation of trifocal IOL following the modified FSAK in Chinese cataract patients exhibited excellent visual efficacy and effectively reduced corneal astigmatism.


Assuntos
Astigmatismo , Catarata , Acuidade Visual , Humanos , Astigmatismo/cirurgia , Astigmatismo/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Catarata/complicações , Implante de Lente Intraocular/métodos , Lentes Intraoculares Multifocais , Adulto , China , Córnea/cirurgia , Córnea/fisiopatologia , Resultado do Tratamento , População do Leste Asiático
2.
Artigo em Inglês | MEDLINE | ID: mdl-38978823

RESUMO

Background: Intrastromal corneal ring segments are commonly implanted in the corneas of eyes with mild-to-moderate keratoconus; however, changes in corneal densitometry (CD) after implantation are a matter of debate in the current literature. We evaluated the changes in CD 1 and 3 months after femtosecond laser-assisted Keraring implantation. Methods: This retrospective, non-comparative, multicenter, case series study included patients with keratoconus who underwent femtosecond laser-assisted implantation of double segments with 90° and 160° arc lengths or two 160° arc length Keraring segments. Demographic and baseline clinical ophthalmic data were recorded. Corneal topography and tomography data acquired using a Pentacam HR Scheimpflug tomography system (Pentacam High Resolution; Oculus, Wetzlar, Germany) with a best-fit sphere were used as a reference surface. Using the Pentacam HR, CD measurements were acquired over a corneal area of 12 mm in total and at four concentric zones (0-2, 2-6, 6-10, and 10-12 mm) of three corneal stromal depths: 120 µm of the anterior corneal stromal layer, 60 µm of the posterior corneal stromal layer, and the central layer of stroma lying between these two layers. Results: We included 40 eyes of 40 patients, including 8 (20%) male and 32 (80%) female individuals, with a mean (standard deviation) age of 21.0 (6.4) years. We observed a significant improvement in the topographic values of steep keratometry (K), flat K, maximum K, and corneal astigmatism (all P < 0.05), but not in the mean K, thinnest corneal pachymetry, corneal thickness at the apex, back elevation, or front elevation (all P > 0.05). The mean total anterior, central, and posterior CD differed significantly among the time points, with a significant increase from the preoperative to the 1-month and 3-month postoperative visits (all P < 0.05) and no difference between those of the 1-month and 3-month postoperative visits (all P > 0.05). The mean CD for the anterior layer in the central, paracentral, and mid-peripheral zones, and the central layer in all four zones, differed significantly among time points, with a significant increase from the preoperative to the 1-month and 3-month postoperative visits (all P < 0.05), which remained unchanged from the 1-month to the 3-month postoperative visit (all P < 0.05), except for the central 2-6-mm zone, which decreased significantly from the 1-month to the 3-month postoperative visit (P < 0.001). The CD of the central 10-12-mm zone did not differ significantly in each pairwise comparison (all P > 0.05). In contrast, CD for the posterior layer in the paracentral zone decreased significantly from the preoperative to the 1-month and 3-month postoperative visits but increased, to a lesser extent, from the 1-month to the 3-month postoperative visit (all P < 0.05). Conclusions: Femtosecond laser-assisted Keraring implantation significantly changes CD, with improvement in most topography parameters. Further longitudinal studies with larger sample sizes are required to verify these preliminary findings.

3.
Biochemistry (Mosc) ; 89(6): 1133-1145, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38981706

RESUMO

Primary excitation energy transfer and charge separation in photosystem I (PSI) from the extremophile desert green alga Chlorella ohadii grown in low light were studied using broadband femtosecond pump-probe spectroscopy in the spectral range from 400 to 850 nm and in the time range from 50 fs to 500 ps. Photochemical reactions were induced by the excitation into the blue and red edges of the chlorophyll Qy absorption band and compared with similar processes in PSI from the cyanobacterium Synechocystis sp. PCC 6803. When PSI from C. ohadii was excited at 660 nm, the processes of energy redistribution in the light-harvesting antenna complex were observed within a time interval of up to 25 ps, while formation of the stable radical ion pair P700+A1- was kinetically heterogeneous with characteristic times of 25 and 120 ps. When PSI was excited into the red edge of the Qy band at 715 nm, primary charge separation reactions occurred within the time range of 7 ps in half of the complexes. In the remaining complexes, formation of the radical ion pair P700+A1- was limited by the energy transfer and occurred with a characteristic time of 70 ps. Similar photochemical reactions in PSI from Synechocystis 6803 were significantly faster: upon excitation at 680 nm, formation of the primary radical ion pairs occurred with a time of 3 ps in ~30% complexes. Excitation at 720 nm resulted in kinetically unresolvable ultrafast primary charge separation in 50% complexes, and subsequent formation of P700+A1- was observed within 25 ps. The photodynamics of PSI from C. ohadii was noticeably similar to the excitation energy transfer and charge separation in PSI from the microalga Chlamydomonas reinhardtii; however, the dynamics of energy transfer in C. ohadii PSI also included slower components.


Assuntos
Chlorella , Transferência de Energia , Complexo de Proteína do Fotossistema I , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema I/química , Chlorella/metabolismo , Synechocystis/metabolismo , Processos Fotoquímicos , Clorofila/metabolismo , Clorofila/química , Cinética
4.
Artigo em Inglês | MEDLINE | ID: mdl-38982632

RESUMO

Plasmonic color printing presents a sustainable solution for vibrant and durable color reproduction by leveraging the light-manipulating properties of nanostructures. However, the fabrication of plasmonic nanostructures has posed challenges, hindering widespread adoption. In this paper, we introduce plasmonic reflector arrays (PRAs) composed of three layers─Ag nanoparticles (NPs), an Al2O3 spacer, and an Ag reflector─deposited via physical vapor deposition (PVD). By employing nanosecond and femtosecond laser writing techniques, we manipulate the surface morphology of silver nanoparticles on PRAs, resulting in a diverse range of structural colors that are both polarization-insensitive and polarization-sensitive. Furthermore, we demonstrate the versatility of nanosecond laser writing in creating intricate patterns on PRAs. Additionally, we propose a novel two-step method combining nanosecond and femtosecond laser processing to embed QR code patterns into PRAs, showcasing their potential for secure data encryption and transmission. This research underscores the promising applications of PRAs in advanced color printing and secure optical data encoding.

5.
BMC Ophthalmol ; 24(1): 276, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982374

RESUMO

BACKGROUND: To investigate the influence of femtosecond laser-assisted cataract surgery (FLACS) on macula by examining changes in retinal layers after FLACS and to compare these changes with those after conventional cataract surgery (CCS). METHODS: This study included 113 unrelated Korean patients with age-related cataract who underwent CCS or FLACS in Severance Hospital between September 2019 and July 2021. Optical coherence tomography was performed before and 1 month after surgery. The total retinal layer (TRL) was separated into the inner retinal layer (IRL) and outer retinal layer (ORL); moreover, the IRL was subdivided into the retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer (INL), outer plexiform layer, and outer nuclear layer. We performed between-group comparisons of the postoperative thickness in each retinal layer and the postoperative differences in retinal thickness. The average retinal thickness of the four inner macular ring quadrants was used for comparative analysis. RESULTS: Compared with the CCS group, the FLACS group exhibited a thicker ORL (P = 0.004) and a thinner INL (P = 0.007) after surgery. All retinal layer thickness values showed significant postoperative changes regardless of the type of surgery (P < 0.05). The postoperative increase in TRL and IRL thickness was significantly smaller in the FLACS group than in the CCS group (P = 0.027, P = 0.012). CONCLUSIONS: The 1-month postoperative retinal changes were less pronounced in the FLACS group than in the CCS group.


Assuntos
Extração de Catarata , Terapia a Laser , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Feminino , Masculino , Tomografia de Coerência Óptica/métodos , Idoso , Terapia a Laser/métodos , Extração de Catarata/métodos , Pessoa de Meia-Idade , Retina/patologia , Retina/diagnóstico por imagem , Estudos Retrospectivos , Fibras Nervosas/patologia , Células Ganglionares da Retina/patologia , Catarata/patologia , Idoso de 80 Anos ou mais , Período Pós-Operatório
6.
Nano Lett ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989671

RESUMO

Herein, an in situ "synchro-subtractive-additive" technique of femtosecond laser single-cell surgery (FLSS) is presented to address the inadequacies of existing surgical methods for single-cell manipulation. This process is enabled by synchronized nanoscale three-dimensional (3D) subtractive and additive manufacturing with ultrahigh precision on various parts of the cells, in that the precise removal and modification of a single-cell structure are realized by nonthermal ablation, with synchronously ultrafast solidification of the specially designed hydrogel by two photopolymerizations. FLSS is a minimally invasive technique with a post-operative survival rate of 70% and stable proliferation. It opens avenues for bottom-up synthetic biology, offering new methods for artificially synthesizing organelle-like 3D structures and modifying the physiological activities of cells.

7.
Nanomaterials (Basel) ; 14(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38869566

RESUMO

Luminescent carbon dots (CDs) were locally synthesized in the core of CYTOP fibers using IR femtosecond laser direct writing (FLDW), a one-step simple method serving as a post-treatment of the pristine fiber. This approach enables the creation of several types of modifications such as ellipsoid voids. The CDs and photoluminescence (PL) distribute at the periphery of the voids. The PL spectral properties were studied through the excitation/emission matrix in the visible range and excitation/emission spectra in the UV/visible range. Our findings reveal the presence of at least three distinct luminescent species, facilitating a broad excitation range extending from UV to green, and light emission spanning from blue to red. The average laser power and dose influence the quantity and ratio of these luminescent CD species. Additionally, we measured the spatially resolved lifetime of the luminescence during and after the irradiation. We found longer lifetimes at the periphery of the laser-induced modified regions and shorter ones closer to the center, with a dominant lifetime ~2 ns. Notably, unlike many other luminophores, these laser-induced CDs are insensitive to oxygen, enhancing their potential for display or data storage applications.

8.
Nano Lett ; 24(23): 7116-7124, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38832663

RESUMO

Controllable droplet manipulation has diverse applications; however, limited methods exist for externally manipulating droplets in confined spaces. Herein, we propose a portable triboelectric electrostatic tweezer (TET) by integrating electrostatic forces with a superhydrophobic surface that can even manipulate droplets in an enclosed space. Electrostatic induction causes the droplet to be subjected to an electrostatic force in an electrostatic field so that the droplet can be moved freely with the TET on a superhydrophobic platform. Characterized by its high precision, flexibility, and robust binding strength, TET can manipulate droplets under various conditions and achieve a wide range of representative fluid applications such as droplet microreactors, precise self-cleaning, cargo transportation, the targeted delivery of chemicals, liquid sorting, soft droplet robotics, and cell labeling. Specifically, TET demonstrated the ability to manipulate internal droplets from the outside of a closed system, such as performing cell labeling experiments within a sealed Petri dish without opening the culture system.

9.
Clin Ophthalmol ; 18: 1655-1666, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863679

RESUMO

Purpose: To evaluate and compare the effect of femtosecond laser-assisted cataract surgery on corneal astigmatism in post-LASIK eyes and virgin eyes. Patients and Methods: Patients who underwent femtosecond laser-assisted cataract surgery were included in the study and categorized into two groups: Group A, consisting of patients with post-LASIK eyes, and Group B, consisting of patients with virgin eyes. Visual acuity, corneal astigmatism, and surgically induced astigmatism (SIA) were evaluated. Additionally, the correlation between SIA and preoperative corneal astigmatism, mean corneal curvature, and central corneal thickness was also analyzed. Results: A total of 168 eyes were enrolled in this study, with 62 eyes in Group A and 106 eyes in Group B. Significant differences in corneal astigmatism and SIA were observed between the two groups in the early postoperative period following cataract surgery (P<0.05). However, there was no significant difference at 6 months postoperatively (P>0.05). Corneal astigmatism demonstrated an against-The-rule shift in both groups postoperatively. No significant correlation was identified between SIA and preoperative corneal astigmatism, corneal curvature or corneal thickness. Additionally, there was no significant difference observed between the two groups in terms of uncorrected distance visual acuity (UDVA) at 6 months postoperatively. Conclusion: The effect of femtosecond laser-assisted cataract surgery on corneal astigmatism in post-LASIK eyes and virgin eyes was different in the early postoperative period. However, there was no significant difference at 6 months postoperatively. The post-LASIK eyes exhibited a delayed recovery compared to the virgin eyes.

10.
Adv Mater ; : e2406081, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886842

RESUMO

Recent advances in the use of stable isotopes necessitate novel synthesis techniques for isotope separation and enrichment that are scalable and offer high throughput. Stable-isotope-enriched nanostructures can offer unique advantages as nanomedicines, safe tracers, and labels and are critical for applications in various industrial processes, metabolic research, and medicine. So far, there exists no method to synthesize miniature isotope-enriched materials at the nanoscale. In this study, an ultrafast Laser-induced isotope enrichment at nanoscale (LIIEN) is put forward to synthesize isotope-enriched nanostructures, eliminating the need for large equipment and expenses, thereby demonstrating a lab-scale isotope enrichment process. A significant isotope enrichment for Carbon nanostructures is observed. The isotope enrichment can be attributed to the redistribution of isotope ions in the plasma plume explained by the plasma centrifuge model. The LIIEN synthesized structures exhibit excellent Surface-Enhanced Raman Scattering (SERS) signal enhancement and reproducibility, making them potential candidates for SERS-based biomolecule sensing. This technique is an efficient method to fabricate nanosized isotope-enriched structures of characteristic properties by carefully tuning laser parameters at ambient conditions.

11.
Fundam Res ; 4(1): 123-130, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38933834

RESUMO

The most important optical component in an optical fiber endoscope is its objective lens. To achieve a high imaging performance level, the development of an ultra-compact objective lens is thus the key to an ultra-thin optical fiber endoscope. In this work, we use femtosecond laser 3D printing to develop a series of micro objective lenses with different optical designs. The imaging resolution and field-of-view performances of these printed micro objective lenses are investigated via both simulations and experiments. For the first time, multiple micro objective lenses with different fields of view are printed on the end face of a single imaging optical fiber, thus realizing the perfect integration of an optical fiber and objective lenses. This work demonstrates the considerable potential of femtosecond laser 3D printing in the fabrication of micro-optical systems and provides a reliable solution for the development of an ultrathin fiber endoscope.

12.
Clin Exp Ophthalmol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38938058

RESUMO

BACKGROUND: To evaluate the results of corneal allogenic intrastromal ring segment (CAIRS) implantation in keratoconus. METHODS: The medical records of patients with keratoconus who underwent CAIRS implantation were reviewed. The CAIRS, prepared by trephination from the donor cornea, was implanted into a tunnel created using the femtosecond laser. The depth of the tunnel was 200 µ; the inner diameter of the tunnel was 4.5 mm; and the outer diameter was 7 mm. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), keratometry, minimum corneal thickness (CT), endothelial cell density (ECD), and high order aberration values were recorded preoperatively and at the 1st, 3rd, and 6th months postoperatively. RESULTS: A total of 23 eyes of 23 patients were included in the study. Preoperative UCVA (0.08 ± 0.01) and BCVA (0.25 ± 0. 11) values improved postoperatively and reached 0.40 ± 0.05 and 0.68 ± 0.09, respectively, at the end of the 6-month follow-up period (p1 < 0.001, p2 = 0.016; respectively). A statistically significant flattening of all keratometric values was observed in the postoperative period compared to preoperatively (p < 0.001 for all). There were no statistical differences between CT and ECC values at the preoperative and postoperative visits (p1 = 0.654, p2 = 0.769; respectively). In addition, coma aberration values were lower than the preoperative values at all postoperative visits (p < 0.05 for all). CONCLUSIONS: These results suggest that CAIRS implantation is a safe treatment option with good visual and keratometric outcomes for suitable patients with keratoconus.

13.
Micromachines (Basel) ; 15(6)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38930755

RESUMO

The sol-gel method is a widely adopted technique for the preparation of tungsten trioxide (WO3) materials, favored for its cost-effectiveness and straightforward production procedures. However, this method encounters challenges such as prolonged annealing periods and limited flexibility in fabricating patterned WO3 films. This study introduces a novel approach that integrates femtosecond laser processing with the sol-gel method to enhance the fabrication of WO3 films. By adjusting polyvinylpyrrolidone (PVP) concentrations during sol-gel synthesis, precise control over film thickness and optimized film properties were achieved. The innovative technique significantly reduced the annealing time required to achieve an 80% transmittance rate from 90 min to 40 min, marking a 56% decrease. Laser processing increased the surface roughness of the films from Sa = 0.032 to Sa = 0.119, facilitating enhanced volatilization of organics during heat treatment. Additionally, this method improved the transmittance modulation of the films by 22% at 550 nm compared to unprocessed counterparts. This approach not only simplifies the manufacturing process but also enhances the optical efficiency of electrochromic devices, potentially leading to broader applications and more effective energy conservation strategies.

14.
Adv Healthc Mater ; : e2400810, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857489

RESUMO

Surface design plays a critical role in determining the integration of dental implants with bone tissue. Femtosecond laser-texturing has emerged as a breakthrough technology offering excellent uniformity and reproducibility in implant surface features. However, when compared to state-of-the-art sandblasted and acid-etched surfaces, laser-textured surface designs typically underperform in terms of osseointegration. This study investigated the capacity of a bio-inspired femtosecond laser-textured surface design to enhance osseointegration compared to state-of-the-art sandblasted & acid-etched surfaces. Laser-texturing facilitates the production of an organized trabeculae-like microarchitecture with superimposed nano-scale laser-induced periodic surface structures on both 2D and 3D samples of titanium-zirconium-alloy. Following a boiling treatment to modify the surface chemistry, improving wettability to a contact angle of 10°, laser-textured surfaces enhance fibrin network formation when in contact with human whole blood, comparable to state-of-the-art surfaces. In vitro experiments demonstrate that laser-textured surfaces significantly outperform state-of-the-art surfaces with a 2.5-fold higher level of mineralization by bone progenitor cells after 28 days of culture. Furthermore, in vivo evaluations reveal superior biomechanical integration of laser-textured surfaces after 28 days of implantation. Notably, during abiological pull-out tests, laser-textured surfaces exhibit comparable performance, suggesting that the observed enhanced osseointegration is primarily driven by the biological response to the surface. This article is protected by copyright. All rights reserved.

15.
BMC Ophthalmol ; 24(1): 206, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711059

RESUMO

PURPOSE: The main objective is to quantify the lens nuclear opacity using spectral-domain optical coherence tomography (SD-OCT) and to evaluate its association with Lens Opacities Classification System III (LOCS-III) system, lens thickness (LT), and surgical parameters. The secondary objective is to assess the diagnostic model performance for hard nuclear cataract. METHODS: This study included 70 eyes of 57 adults with cataract, with 49 (70%) and 21 (30%) in training and validation cohort, respectively. Correlations of the average nuclear density (AND) /maximum nuclear density (MND) with LOCS-III scores, LT, and surgical parameters were analyzed. Univariate and multivariate logistic regression analysis, receiver operating characteristic curves and calibration curves were performed for the diagnostic of hard nuclear cataract. RESULTS: The pre-operative uncorrected distance visual acuity (UDVA), intraocular pressure (IOP), mean axial length (AL), and LT were 1.20 ± 0.47 log MAR, 15.50 ± 2.87 mmHg, 27.34 ± 3.77 mm and 4.32 ± 0.45 mm, respectively. The average nuclear opalescence (NO) and nuclear colour (NC) scores were 3.61 ± 0.94 and 3.50 ± 0.91 (ranging from 1.00 to 6.90), respectively. The average AND and MND were 137.94 ± 17.01 and 230.01 ± 8.91, respectively. NC and NO scores both significantly correlated with the AND (rNC = 0.733, p = 0.000; rNO = 0.755, p = 0.000) and MND (rNC = 0.643, p = 0.000; rNO = 0.634, p = 0.000). In the training cohort, the area under the curve (AUC) of the model was 0.769 (P < 0.001, 95%CI 0.620-0.919), which had a good degree of differentiation (Fig. 2a). The calibration curve showed good agreement between predicted and actual probability. CONCLUSION: The nuclear density measurement on SD-OCT images can serve as an objective and reliable indicator for quantifying nuclear density.


Assuntos
Catarata , Núcleo do Cristalino , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Feminino , Masculino , Tomografia de Coerência Óptica/métodos , Catarata/diagnóstico , Idoso , Pessoa de Meia-Idade , Núcleo do Cristalino/patologia , Núcleo do Cristalino/diagnóstico por imagem , Acuidade Visual/fisiologia , Curva ROC , Estudos Retrospectivos , Facoemulsificação , Idoso de 80 Anos ou mais , Adulto , Cristalino/diagnóstico por imagem , Cristalino/patologia
16.
Int J Ophthalmol ; 17(3): 596-602, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721520

RESUMO

AIM: To explore the clinical efficacy and safety of stromal lenticule addition keratoplasty (SLAK) with corneal crosslinking (CXL) on patients with corneal ectasia secondary to femtosecond laser-assisted in situ keratomileusis (FS-LASIK). METHODS: A series of 5 patients undertaking SLAK with CXL for the treatment of corneal ectasia secondary to FS-LASIK were followed for 4-9mo. The lenticules were collected from patients undertaking small incision lenticule extraction (SMILE) for the correction of myopia. Adding a stromal lenticule was aimed at improving the corneal thickness for the safe application of crosslinking and compensating for the thin cornea to improve its mechanical strength. RESULTS: All surgeries were conducted successfully with no significant complications. Their best corrected visual acuity (BCVA) ranged from 0.05 to 0.8-2 before surgery. The pre-operational total corneal thickness ranged from 345-404 µm and maximum keratometry (Kmax) ranged from 50.8 to 86.3. After the combination surgery, both the corneal keratometry (range 55.9 to 92.8) and total corneal thickness (range 413-482 µm) significantly increased. Four out of 5 patients had improvement of corneal biomechanical parameters (reflected by stiffness parameter A1 in Corvis ST). However, 3 patients showed decreased BCVA after surgery due to the development of irregular astigmatism and transient haze. Despite the onset of corneal edema right after SLAK, the corneal topography and thickness generally stabilized after 3mo. CONCLUSION: SLAK with CXL is a potentially beneficial and safe therapy for advanced corneal ectasia. Future work needs to address the poor predictability of corneal refractometry and compare the outcomes of different surgical modes.

17.
Nanotechnology ; 35(36)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38749414

RESUMO

Multi-photon reduction (MPR) based on femtosecond laser makes rapid prototyping and molding in micro-nano scale feasible, but is limited in material selectivity due to lack of the understanding of the reaction mechanism in MPR process. In this paper, additively manufacturing of complex silver-based patterns through MPR is demonstrated. The effects of laser parameters, including laser pulse energies and scanning speeds, on the structural and chemical characteristics of the printed structures are systematically investigated. The results show that the geometric size of printed cubes deviates from the designed size further by increasing laser pulse energy or decreasing scanning speed. The reaction mechanism of MPR is revealed by studying the elemental composition and chemical structures of printed cubes. The evolution of Raman spectra upon the laser processing parameters suggests that the MPR process mainly includes two processes: reduction and decomposition. In the MPR process, silver ions are reduced and grow into particles by accepting the electrons from ethonal molecules; meanwhile carboxyl groups in polyvinylpyrrolidone are decomposed and form amorphous carbon that is attached on the surface of silver particles. The conductivity of silver wires fabricated by MPR reaches 2 × 105S m-1and stays relatively constant as varying their cross section area, suggesting excellent electrical conduction. The understanding of the MPR process would accelerate the development of MPR technology and the implementation of MPR in micro-electromechanical systems could therefore be envisioned.

18.
BMC Ophthalmol ; 24(1): 212, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750496

RESUMO

BACKGROUND: To evaluate differences in log MAR best-corrected visual acuity (BCVA) improvement and postoperative central foveal thickness (CFT) and choroidal thickness (CT) changes between conventional phacoemulsification surgery (CPS) and femtosecond laser-assisted cataract surgery (FLACS) for high-myopia cataracts. METHODS: This was a retrospective and observational study. One hundred and two eyes of 102 patients with high-myopia cataracts were examined. CPS was performed in 54 eyes, and FLACS was performed in 48 eyes. All eyes underwent logMAR BCVA, CFT and CT of three different sectors preoperatively and one week and six months postoperatively. RESULTS: The logMAR BCVA improved significantly after surgery in both groups (both P < 0.001), but no difference was observed in BCVA improvement between the groups (P = 0.554). Moreover, no significant differences were reflected in the changes in CFT, nasal 1 mm CT or temporal 1 mm CT between the two groups, and only subfoveal choroidal thickness (SFCT) in the CPS group decreased significantly compared with that in the FLACS group at any postoperative time (P = 0.003 and 0.026). AL, preoperative logMAR BCVA, and CT of the three regions exhibited a notable correlation with postoperative BCVA (all P < 0.05) according to univariate logistic regression analysis. However, only the AL, preoperative logMAR BCVA and SFCT remained significant in the multivariate model. Postoperative logMAR BCVA revealed a positive correlation with AL and preoperative logMAR BCVA but a negative correlation with SFCT. CONCLUSIONS: FLACS was not superior to CPS in improving BCVA but had less impact on SFCT in the treatment of high-myopia cataracts. Eyes with a longer AL, worse preoperative logMAR BCVA and thinner SFCT had a high risk of worse postoperative BCVA.


Assuntos
Catarata , Terapia a Laser , Facoemulsificação , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Estudos Retrospectivos , Feminino , Masculino , Facoemulsificação/métodos , Acuidade Visual/fisiologia , Pessoa de Meia-Idade , Idoso , Terapia a Laser/métodos , Catarata/complicações , Catarata/fisiopatologia , Tomografia de Coerência Óptica/métodos , Macula Lutea/diagnóstico por imagem , Macula Lutea/patologia , Extração de Catarata/métodos , Miopia Degenerativa/fisiopatologia , Miopia Degenerativa/cirurgia , Miopia Degenerativa/complicações , Corioide/diagnóstico por imagem , Resultado do Tratamento
19.
Angew Chem Int Ed Engl ; : e202406292, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780997

RESUMO

Aqueous Zn-ion batteries are an attractive electrochemical energy storage solution for their budget and safe properties. However, dendrites and uncontrolled side reactions in anodes detract the cycle life and energy density of the batteries. Grain boundaries in metals are generally considered as the source of the above problems but we present a diverse result. This study introduces an ultra-high proportion of grain boundaries on zinc electrodes through femtosecond laser bombardment to enhance stability of zinc metal/electrolyte interface. The ultra-high proportion of grain boundaries promotes the homogenization of zinc growth potential, to achieve uniform nucleation and growth, thereby suppressing dendrite formation. Additionally, the abundant active sites mitigate the side reactions during the electrochemical process. Consequently, the 15 µm Fs-Zn||MnO2 pouch cell achieves an energy density of 249.4 Wh kg-1 and operates for over 60 cycles at a depth-of-discharge of 23 %. The recognition of the favorable influence exerted by UP-GBs paves a new way for other metal batteries.

20.
Acta Biomater ; 183: 356-370, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38768742

RESUMO

Zirconia is one of the most commonly used materials for abutments of dental implants, especially in the anterior region. Soft tissue integration to the zirconia abutment surface remains a challenge. Peri-implant soft tissue integration serves as a physiological barrier, attenuating pathogen penetration and preventing peri­implant disease. The surface microstructure of zirconia has significant effects on the biological behaviors of human gingival fibroblasts (HGFs), but the effects under inflammatory conditions are still unclear. In this study, we established two micro-nano structures on zirconia surfaces using a femtosecond laser, including microgrooves with widths of 30 µm (G3) and 60 µm (G6) and depths of 5 µm, and nanoparticles inside the microgrooves. Polished surfaces were used as controls. HGFs were seeded onto the three groups of zirconia specimens and stimulated with lipopolysaccharide. The HGFs on micro-nano-structured zirconia surfaces exhibited lower inflammatory responses and higher cell adhesion, proliferation, and migration under inflammatory conditions compared with the polished surfaces. Additionally, the G3 group exhibited lower inflammatory responses and higher cell adhesion and migration than the G6 group. The micro-nano-structured zirconia surface exhibited decreased neutrophil infiltration and increased M2-type macrophage polarization in vivo. To explore the molecular mechanism, RNA sequencing and gene silencing were utilized, which revealed two critical target genes regulated by the G3 group. Overall, we proposed an innovative micro-nano-structured zirconia surface that reduced the in vitro and in vivo inflammatory responses and promoted HGF adhesion, migration, and proliferation under inflammatory conditions, in which TRAFD1 and NLRC5 were the underlying key genes. STATEMENT OF SIGNIFICANCE: Zirconia is one of the most commonly used materials for abutments, especially in the anterior region. The surface microstructure of zirconia has significant effects on the biological behaviors of human gingival fibroblasts (HGFs), but few studies have investigated these effects under inflammatory conditions, and the mechanism remains unclear. In this study, we developed an innovative micro-nano-structured zirconia surface using a femtosecond laser, which reduces the in vitro and in vivo pro-inflammatory responses and promotes HGFs adhesion, migration, and proliferation under inflammatory conditions compared with the polished zirconia surface. The potential underlying mechanism was also investigated. This work has provided some theoretical basis for the micro-nano-structured zirconia surface in potentially reducing the inflammation and enhancing peri­implant soft-tissue integration under inflammatory conditions.


Assuntos
Fibroblastos , Gengiva , Inflamação , Propriedades de Superfície , Zircônio , Zircônio/farmacologia , Zircônio/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Gengiva/citologia , Inflamação/patologia , Proliferação de Células/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Nanoestruturas/química , Camundongos , Masculino
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