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1.
Biomater Adv ; 138: 212950, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35913239

RESUMO

To provide antibacterial properties, the titanium samples were subjected to electrochemical oxidation in the fluoride-containing diethylene glycol-based electrolyte to create a titanium oxide nanotubular surface. Afterward, the surface was covered by sputtering with silver 5 nm film, and the tops of the nanotubes were capped using laser treatment, resulting in an appearance of silver nanoparticles (AgNPs) of around 30 nm in diameter on such a modified surface. To ensure a controlled release of the bactericidal substance, the samples were additionally coated with a pH-sensitive chitosan/Eudragit 100 coating, also exhibiting bactericidal properties. The modified titanium samples were characterized using SEM, EDS, AFM, Raman, and XPS techniques. The wettability, corrosion properties, adhesion of the coating to the substrate, the release of AgNPs into solutions simulating body fluids at different pH, and antibacterial properties were further investigated. The obtained composite coatings were hydrophilic, adjacent to the surface, and corrosion-resistant. An increase in the amount of silver released as ions or metallic particles into a simulated body fluid solution at acidic pH was observed for modified samples with the biopolymer coating after three days of exposure avoiding burst effect. The proposed modification was effective against both Gram-positive and Gram-negative bacteria.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanotubos , Antibacterianos/farmacologia , Quitosana/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Lasers , Nanopartículas Metálicas/química , Nanotubos/química , Polímeros , Ácidos Polimetacrílicos , Prata/farmacologia , Titânio/farmacologia
3.
Med Sci Monit ; 28: e936713, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35918878

RESUMO

BACKGROUND Accurate estimation of burn depth is crucial for correct treatment decision making. Bromelain-based enzymatic debridement (ED) may improve clinical assessment of burn depth. Laser Doppler imaging (LDI) provides a valuable indicator of burn depth by analyzing microcirculation within tissue beds. This study aimed to evaluate bromelain-based enzymatic debridement combined with laser Doppler imaging and healing of 42 wounds in 19 patients with mixed second- and third-degree thermal burns. MATERIAL AND METHODS We included 42 wounds in 19 patients with mixed deep dermal and full-thickness thermal burns. All patients were treated with eschar-specific removal agent for ED. The perfusion of each wound after ED was assessed using LDI. Healing time was estimated by 2 experienced burn surgeons and marked by the observation of epithelization. The usefulness of the LDI performed after ED in predicting healing time was estimated. The findings were analyzed to determine a cut-off value for LDI that indicates if a burn will heal spontaneously. RESULTS We observed that burn wounds with higher mean perfusion healed faster. The analysis showed a strong relationship between perfusion after ED and healing time (Spearman rank correlation coefficient=-0.803). A mean perfusion greater than 296.89 indicated that the wound could heal spontaneously and does not require skin grafting. CONCLUSIONS LDI examination of an already debrided wound allows for a reliable assessment of perfusion at an early stage of treatment. The use of a safe and effective debridement method in conjunction with a non-invasive diagnostic tool could improve burn management.


Assuntos
Bromelaínas , Queimaduras , Bromelaínas/farmacologia , Bromelaínas/uso terapêutico , Queimaduras/diagnóstico por imagem , Queimaduras/terapia , Desbridamento/métodos , Humanos , Lasers , Pele , Cicatrização
4.
Indian J Ophthalmol ; 70(8): 2877-2882, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35918935

RESUMO

Purpose: To compare image characteristics of retinal nerve fiber layer (RNFL) between glaucoma patients and healthy controls using adaptive optics scanning laser ophthalmoscopy (AOSLO). Methods: This was a cross-sectional pilot study with two groups: a glaucoma group with patients with moderate or severe glaucoma as per the Hodapp-Parrish-Anderson classification system and a control group with healthy individuals. The optic nerve damage in moderate glaucoma was predominantly located in only one hemisphere; the other hemisphere was un- or minimally affected on optical coherence tomography and automated perimetry and is referred to as early glaucoma. The structure of RNFL bundles and gain (%) in RNFL images with mean pixel values between 15 and 35 were analyzed. Imaging was performed one degree away from the optic disc margin at two and four cardinal clock positions in the glaucoma and control groups, respectively. The field of view was 1.3° at 2.3 µ resolution. We studied one eye per participant. Results: There were 11 glaucoma patients and 7 healthy controls. Imaging was successful at 88% of the locations in controls and early glaucoma; the reflectivity differed significantly (0.51 and 0.56, respectively, P < 0.001) but not the structure of RNFL bundles (Cohen's Kappa 0.11) between them. In patients with moderate and severe glaucoma, imaging was successful only at 46% of the locations; RNFL bundles were not discernible, and RNFL reflectivity did not differ from those with early glaucoma (P < 0.11). Conclusion: The recorded gain (%) of RNFL images obtained using AOSLO could be an objective indicator of early glaucoma.


Assuntos
Glaucoma , Fibras Nervosas , Estudos Transversais , Diagnóstico Precoce , Glaucoma/diagnóstico , Humanos , Lasers , Oftalmoscopia/métodos , Projetos Piloto , Tomografia de Coerência Óptica/métodos
5.
Biomater Adv ; 135: 212748, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35929220

RESUMO

Incorporation of a bioactive mineral filler in a biodegradable polyester scaffold is a promising strategy for scaffold assisted bone tissue engineering (TE). The current study evaluates the in vitro behavior of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV)/Akermanite (AKM) composite scaffolds manufactured using selective laser sintering (SLS). Exposure of the mineral filler on the surface of the scaffold skeleton was evident from in vitro mineralization in PBS. PHBV scaffolds and solvent cast films served as control samples and all materials showed preferential adsorption of fibronectin compared to serum albumin as well as non-cytotoxic response in human osteoblasts (hOB) at 24 h. hOB culture for up to 21 days revealed that the metabolic activity in PHBV films and scaffolds was significantly higher than that of PHBV/AKM scaffolds within the first two weeks of incubation. Afterwards, the metabolic activity in PHBV/AKM scaffolds exceeded that of the control samples. Confocal imaging showed cell penetration into the porous scaffolds. Significantly higher ALP activity was observed in PHBV/AKM scaffolds at all time points in both basal and osteogenic media. Mineralization during cell culture was observed on all samples with PHBV/AKM scaffolds exhibiting distinctly different mineral morphology. This study has demonstrated that the bioactivity of PHBV SLS scaffolds can be enhanced by incorporating AKM, making this an attractive candidate for bone TE application.


Assuntos
Poliésteres , Tecidos Suporte , Cerâmica , Humanos , Hidroxibutiratos , Lasers , Porosidade
6.
Biomater Adv ; 137: 212829, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35929262

RESUMO

Lattice structures are widely used in orthopedic implants due to their unique features, such as high strength-to-weight ratios and adjustable biomechanical properties. Based on the type of unit cell geometry, lattice structures may be classified into two types: strut-based structures and sheet-based structures. In this study, strut-based structures (Cubic & Octet) and sheet-based structure (triply periodic minimal surface (TPMS) gyroid) were investigated. The biomechanical properties of the three different Ti6Al4V lattice structures fabricated by selective laser melting (SLM) were investigated using room temperature compression testing. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to check the 3D printing quality with regards to defects and quantitative compositional information of 3D printed parts. Experimental results indicated that TPMS gyroid has superior biomechanical properties when compared to Cubic and Octet. Also, TPMS gyroid was found to be less affected by the variations in relative density. The biocompatibility of Ti6Al4V lattice structures was validated through the cytotoxicity test with human osteoblast-like SAOS2 cells. The debris generated during the degradation process in the form of particles and ions is among the primary causes of implant failure over time. In this study, Ti6Al4V particles with spherical and irregular shapes having average particle sizes of 36.5 µm and 28.8 µm, respectively, were used to mimic the actual Ti6Al4V particles to understand their harmful effects better. Also, the effects and amount of Ti6Al4V ions released after immersion within the cell culture media were investigated using the indirect cytotoxicity test and ion release test.


Assuntos
Lasers , Osteoblastos , Ligas , Humanos , Teste de Materiais , Porosidade , Titânio
7.
J Nanobiotechnology ; 20(1): 365, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933376

RESUMO

The failure of orthopedic and dental implants is mainly caused by biomaterial-associated infections and poor osseointegration. Surface modification of biomedical materials plays a significant role in enhancing osseointegration and anti-bacterial infection. In this work, a non-linear relationship between the micro/nano surface structures and the femtosecond laser processing parameters was successfully established based on an artificial neural network. Then a controllable functional surface with silver nanoparticles (AgNPs) to was produced to improve the cytocompatibility and antibacterial properties of biomedical titanium alloy. The surface topography, wettability, and Ag+ release were carefully investigated. The effects of these characteristics on antibacterial activity and cytocompatibilty were also evaluated. Results show that the prepared surface is hydrophobic, which can prevent the burst release of Ag+ in the initial stage. The prepared surface also shows both good cytocompatibility toward the murine calvarial preosteoblasts MC3T3-E1 cells (derived from Mus musculus (mouse) calvaria) and good antibacterial effects against Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, which is caused by the combined effect of appropriate micro/nano-structured feature and reasonable Ag+ release rate. We do not only clarify the antibacterial mechanism but also demonstrate the possibility of balancing the antibacterial and osteointegration-promoting properties by micro/nano-structures. The reported method offers an effective strategy for the patterned surface modification of implants.


Assuntos
Nanopartículas Metálicas , Prata , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli , Lasers , Nanopartículas Metálicas/química , Camundongos , Redes Neurais de Computação , Prata/química , Prata/farmacologia , Staphylococcus aureus , Propriedades de Superfície , Titânio/química
8.
Transl Vis Sci Technol ; 11(8): 1, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913417

RESUMO

Purpose: The purpose of this study was to evaluate the pathological involvement of erythropoietin (EPO) in experimental choroidal neovascularization (CNV) and its association with neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) in the Chinese population. Methods: Treatment effect of recombinant EPO protein were assessed by human umbilical vein endothelial cell (HUVEC) proliferation, migration, and tube formation, and ex vivo choroid-sprouting ability. The effect of intravitreal injection of Epo siRNA against neovascularization was evaluated in the laser-induced CNV mouse model. In addition, the association of EPO variants with neovascular AMD and PCV was determined. Results: Exogenous supplementation of EPO significantly enhanced the migration and tube formation of HUVECs and promoted ex vivo choroid sprouting in mouse retinal pigment epithelium (RPE)-choroid-sclera complex culture. In the experimental CNV mouse model, Epo expression was found to be significantly upregulated by 3.5-folds in RPE-choroid-sclera complex at day 10 after laser induction as compared to the baseline. Immunofluorescence analysis showed that Epo was mainly expressed around the vascular endothelial cells in the RPE-choroid-sclera complex. Intravitreal injection of siRNA targeting Epo reduced 40% Epo expression and 40% CNV lesion areas as compared to the scramble control. However, EPO variants were not associated with neovascular AMD nor PCV in the Chinese population. Conclusions: This study revealed the promotion of human endothelial cell tube formation in vitro and choroid sprouting ex vivo by EPO, and the reduction of laser-induced CNV in vivo by Epo RNA interference. Translational Relevance: Targeting EPO could be a potential additional treatment for CNV-related diseases.


Assuntos
Doenças da Coroide , Neovascularização de Coroide , Eritropoetina , Degeneração Macular Exsudativa , Inibidores da Angiogênese , Animais , Doenças da Coroide/genética , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/genética , Eritropoetina/genética , Eritropoetina/metabolismo , Eritropoetina/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Lasers , Camundongos , Interferência de RNA , RNA Interferente Pequeno/genética , Acuidade Visual , Degeneração Macular Exsudativa/genética
9.
Sci Rep ; 12(1): 13285, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918378

RESUMO

Percutaneous laser discectomy is one common and effective treatment for cervical radicular pain. Currently, the surgery is performed with blind cannulation technique, mainly relies on the experience of surgeon. However, it still remains unsafe and difficult to reach the target. As an alternative, ultrasound-guided cannulation provides visualization of important structures, thus increasing the precision and safety. The primary goal of this study is to report the detail of the ultrasound-guided technique in the percutaneous laser cervical discectomy. The secondary purpose is to evaluate the feasibility of the novel therapy. This is a single center, feasibility study conducted in one teaching hospital. Thirteen intervertebral discs in 9 patients presented with cervical radicular pain. Accuracy of the cannulation with ultrasonic guidance was confirmed by the anterior-posterior and lateral view of fluoroscopy. We compared the pain severity pre- and post-treatment with Visual Analogue Score (VAS), and functional improvement was assessed with the modified Macnab Criteria and Neck Disability Index (NDI) respectively. Ultrasonic short-axis was used to scan the cervical nerve root, and its transition was used to identify the distinct intervertebral space. Following the recognition of targeted cervical level, the ultrasound probe was moved medially for the visualization of the surface of the cervical vertebrae. In plane cannulation was then applied to avoid the injury of the vessels. The location of cannula was confirmed by the fluoroscopic imaging. Low-power laser was set for the cervical disc ablation in this cohort. The majority of the surgical sites maintained in the C5/6 level (38%), and 31% for the C6/7 level respectively. Despite the distinct cervical level, the tip of needle was properly placed near by the targeted intervertebral disc in all participants, which was confirmed by the imaging of fluoroscopy. We did not observe any obvious complications during the procedure. The mean VAS decreased from 7.6 ± 1.1 to 2.3 ± 2.7 one month after discharge, and 2.1 ± 2.6 at the last follow-up (median duration of nine months). All patients reported significant improvement of NDI up to last follow-up (p = 0.011). Meanwhile, the good to excellent rate was reported in 8 of 9 patients (89%) according to the modified Macnab Criteria. The finding of this feasibility assessment indicates the ultrasound-based cannulation technique is capable of guiding the cannulation for the percutaneous laser discectomy. It may facilitate identifying the corresponding site of cervical intervertebral disc and prevent the damage of vessel.


Assuntos
Deslocamento do Disco Intervertebral , Radiculopatia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Discotomia/efeitos adversos , Estudos de Viabilidade , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Lasers , Cervicalgia/complicações , Radiculopatia/complicações , Radiculopatia/diagnóstico por imagem , Radiculopatia/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção/efeitos adversos
10.
J Refract Surg ; 38(8): 480-486, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35947005

RESUMO

PURPOSE: To evaluate the predictors related to the efficacy of epithelium- and Bowman membrane-penetrating femtosecond laser-assisted arcuate keratotomy (FSAK) in the treatment of preoperative astigmatism in patients with cataracts and to clarify the predictive role of the incision-to-limbus distance. METHODS: This retrospective study included patients who underwent femtosecond laser-assisted cataract surgery combined with FSAK using the LenSX platform (Alcon Laboratories, Inc) at Beijing Aier-Intech Eye Hospital from March 2017 to December 2021. The Lenstar LS900 (Haag-Streit, Inc) was used to measure the horizontal corneal diameter, and ImageJ software (National Institutes of Health) was used to measure the vertical corneal diameter and incision-to-limbus distance. Finally, the measured values were converted. Changes in corneal astigmatism before and 3 months after surgery were analyzed using Alpins vector analysis. Correlation analysis and regression analysis were used to evaluate the factors associated with surgically induced astigmatism (SIA) in preoperative ocular biometric parameters. RESULTS: The study included 94 eyes of 94 patients. The mean target induced astigmatism was 1.36 ± 0.44 diopters (D), SIA was 0.82 ± 0.43 D, and mean difference vector was 0.70 ± 0.40 D. Pearson correlation analysis and univariate regression analysis showed that preoperative corneal astigmatism, arcuate keratotomy arc length, incision-to-limbus distance, and astigmatism type were significant predictors of SIA. Multiple variable regression analysis included parameters such as age, arcuate keratotomy arc length, and incision-to-limbus distance and established a multiple regression model of SIA (all P < .01). CONCLUSIONS: The incision-to-limbus distance was a significant independent predictor of SIA, and inclusion of this parameter may further improve the accuracy of the nomogram. [J Refract Surg. 2022;38(8):480-486.].


Assuntos
Astigmatismo , Catarata , Doenças da Córnea , Astigmatismo/complicações , Astigmatismo/cirurgia , Catarata/complicações , Córnea/cirurgia , Doenças da Córnea/cirurgia , Topografia da Córnea , Humanos , Lasers , Refração Ocular , Estudos Retrospectivos , Acuidade Visual
11.
Neurosurg Focus ; 52(6): E9, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35921184

RESUMO

OBJECTIVE: Communication between neurosurgeons and pathologists is mandatory for intraoperative decision-making and optimization of resection, especially for invasive masses. Handheld confocal laser endomicroscopy (CLE) technology provides in vivo intraoperative visualization of tissue histoarchitecture at cellular resolution. The authors evaluated the feasibility of using an innovative surgical telepathology software platform (TSP) to establish real-time, on-the-fly remote communication between the neurosurgeon using CLE and the pathologist. METHODS: CLE and a TSP were integrated into the surgical workflow for 11 patients with brain masses (6 patients with gliomas, 3 with other primary tumors, 1 with metastasis, and 1 with reactive brain tissue). Neurosurgeons used CLE to generate video-flow images of the operative field that were displayed on monitors in the operating room. The pathologist simultaneously viewed video-flow CLE imaging using a digital tablet and communicated with the surgeon while physically located outside the operating room (1 pathologist was in another state, 4 were at home, and 6 were elsewhere in the hospital). Interpretations of the still CLE images and video-flow CLE imaging were compared with the findings on the corresponding frozen and permanent H&E histology sections. RESULTS: Overall, 24 optical biopsies were acquired with mean ± SD 2 ± 1 optical biopsies per case. The mean duration of CLE system use was 1 ± 0.3 minutes/case and 0.25 ± 0.23 seconds/optical biopsy. The first image with identifiable histopathological features was acquired within 6 ± 0.1 seconds. Frozen sections were processed within 23 ± 2.8 minutes, which was significantly longer than CLE usage (p < 0.001). Video-flow CLE was used to correctly interpret tissue histoarchitecture in 96% of optical biopsies, which was substantially higher than the accuracy of using still CLE images (63%) (p = 0.005). CONCLUSIONS: When CLE is employed in tandem with a TSP, neurosurgeons and pathologists can view and interpret CLE images remotely and in real time without the need to biopsy tissue. A TSP allowed neurosurgeons to receive real-time feedback on the optically interrogated tissue microstructure, thereby improving cross-functional communication and intraoperative decision-making and resulting in significant workflow advantages over the use of frozen section analysis.


Assuntos
Glioma , Telepatologia , Endoscopia/métodos , Humanos , Lasers , Microscopia Confocal/métodos
12.
Klin Lab Diagn ; 67(7): 407-413, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35924771

RESUMO

The development of mycotic colonization of the base surface with further biodegradation of acrylic plastics is currently of undoubted interest. The oral cavity is a favorable ecological niche for colonization by fungi and their subsequent possible invasion into the epithelium of the oral mucosa. The method of modulation interference laser microscopy is of considerable interest to researchers in medicine in the context of obtaining the necessary information about the morphological characteristics of microbial cells and the microbiome community as a whole during the colonization of a certain ecological niche in the human body. Purpose of the study: to analyze the microrelief of the biofilm of yeast-like fungi of the species Candida albicans of base plastics of the hot type of polymerization using the method of laser modulation interference microscopy. An experimental study was carried out in order to study biofilms of yeast-like fungi of the genus Candida on samples of basic plastics, an image of a biofilm of yeast-like fungi of the species Candida albicans was obtained on the surface of a plastic of a hot type of polymerization (polymethyl methacrylate) in the visualization of the phase portrait, a description of its horizontal and vertical bioprofile. As a result of the research, the heterogeneous structure of the biofilm was determined, due to the different density and accumulation of cells along the surface, the characteristics of the surface were established in accordance with the roughness criteria. The microrelief parameters on a separately arbitrarily selected section line allow one to determine the characteristics of the biofilm in the required area and make it possible to judge the nature of its formation in a certain biological niche.


Assuntos
Candida albicans , Plásticos , Biofilmes , Humanos , Lasers , Microscopia Confocal , Microscopia de Interferência
13.
J Environ Public Health ; 2022: 8225322, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910751

RESUMO

Three-dimensional laser scanning technology can comprehensively and accurately monitor slope deformation. To conduct deformation monitoring and stability evaluation of the Changzhou Shunguoshan landslide, in this paper, the causes of the Changzhou Shunguoshan landslide were analyzed. Consequently, 3D laser scanning technology and the traditional monitoring methods such as data from the total station were compared. The point cloud data provides big data support for landslide deformation monitoring and landslide stability early warning. Meanwhile, the landslide stability was evaluated by analogy with existing studies on slope deformation monitoring data. Results show that the three-dimensional laser scanning monitoring data is similar to the total station monitoring data. The overall deformation of the Shunguoshan landslide is no more than ± 0.0015 m; the deformation of the Liyang slope is less than ±0.09 m, which is far less than the analog slope deformation monitoring data. The slope construction and monitoring process are in a stable state.


Assuntos
Deslizamentos de Terra , Lasers
14.
Opt Lett ; 47(15): 3700-3703, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913293

RESUMO

A multi-channel parallel ultrasound detection system based on a photothermal tunable fiber optic sensor array is proposed. The resonant wavelength of the ultrasound sensor has a quadratic relationship with the power of a 980-nm heating laser. The maximum tuning range is larger than 15 nm. Through photothermal tuning, the inconsistent operating wavelengths of the Fabry-Perot (FP) sensor array can be solved, and then a multiplexing capacity of up to 53 can be theoretically realized, which could greatly reduce the time required for data acquisition. Then, a fixed wavelength laser with ultra-narrow linewidth is used to interrogate the sensor array. The interrogation system demonstrates a noise equivalent pressure (NEP) as low as 0.12 kPa, which is 5.5-times lower than the commercial hydrophone. Furthermore, a prototype of a four-channel ultrasound detection system is built to demonstrate the parallel detection capability. Compared with the independent detection, the SNR of parallel detection does not deteriorate, proving that the parallel detection system and the sensor array own very low cross talk characteristics. The parallel detection technique paves a way for real-time photoacoustic/ultrasound imaging.


Assuntos
Tecnologia de Fibra Óptica , Lasers , Desenho de Equipamento , Ultrassonografia
15.
J Vis Exp ; (185)2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35913186

RESUMO

Lipid profiling, or lipidomics, is a well-established technique used to study the entire lipid content of a cell or tissue. Information acquired from lipidomics is valuable in studying the pathways involved in development, disease, and cellular metabolism. Many tools and instrumentations have aided lipidomics projects, most notably various combinations of mass spectrometry and liquid chromatography techniques. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) has recently emerged as a powerful imaging technique that complements conventional approaches. This novel technique provides unique information on the spatial distribution of lipids within tissue compartments, which was previously unattainable without the use of excessive modifications. The sample preparation of the MALDI MSI approach is critical and, therefore, is the focus of this paper. This paper presents a rapid lipid analysis of a large number of Drosophila brains embedded in optimal cutting temperature compound (OCT) to provide a detailed protocol for the preparation of small tissues for lipid analysis or metabolite and small molecule analysis through MALDI MSI.


Assuntos
Drosophila , Lipídeos , Animais , Encéfalo/diagnóstico por imagem , Lasers , Lipídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
16.
Transl Vis Sci Technol ; 11(8): 7, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35938881

RESUMO

Purpose: Accurate segmentation of microaneurysms (MAs) from adaptive optics scanning laser ophthalmoscopy (AOSLO) images is crucial for identifying MA morphologies and assessing the hemodynamics inside the MAs. Herein, we introduce AOSLO-net to perform automatic MA segmentation from AOSLO images of diabetic retinas. Method: AOSLO-net is composed of a deep neural network based on UNet with a pretrained EfficientNet as the encoder. We have designed customized preprocessing and postprocessing policies for AOSLO images, including generation of multichannel images, de-noising, contrast enhancement, ensemble and union of model predictions, to optimize the MA segmentation. AOSLO-net is trained and tested using 87 MAs imaged from 28 eyes of 20 subjects with varying severity of diabetic retinopathy (DR), which is the largest available AOSLO dataset for MA detection. To avoid the overfitting in the model training process, we augment the training data by flipping, rotating, scaling the original image to increase the diversity of data available for model training. Results: The validity of the model is demonstrated by the good agreement between the predictions of AOSLO-net and the MA masks generated by ophthalmologists and skillful trainees on 87 patient-specific MA images. Our results show that AOSLO-net outperforms the state-of-the-art segmentation model (nnUNet) both in accuracy (e.g., intersection over union and Dice scores), as well as computational cost. Conclusions: We demonstrate that AOSLO-net provides high-quality of MA segmentation from AOSLO images that enables correct MA morphological classification. Translational Relevance: As the first attempt to automatically segment retinal MAs from AOSLO images, AOSLO-net could facilitate the pathological study of DR and help ophthalmologists make disease prognoses.


Assuntos
Aprendizado Profundo , Retinopatia Diabética , Microaneurisma , Retinopatia Diabética/diagnóstico por imagem , Humanos , Lasers , Microaneurisma/diagnóstico por imagem , Oftalmoscopia/métodos , Óptica e Fotônica
17.
Diagn Interv Radiol ; 28(4): 352-358, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35950279

RESUMO

PURPOSE Patients with acute calculus cholecystitis and contraindications to cholecystectomy receive cholecystostomy drainage catheters, many of which remain in place until end of life. This study aims to assess safety, feasibility, and early clinical outcomes of percutaneous cholecystoscopy using the LithoVue endoscope, laser/mechanical cholelithotripsy, and mechanical cholelithotomy for management of symptomatic cholelithiasis. METHODS This was a single-institute retrospective analysis of 17 patients with acute calculus cholecystitis who had contraindications to cholecystectomy, underwent cholecystostomy catheter placement between 2015 and 2017, and stone removal between 2017 and 2018. The LithoVue 7.7- 9.5 F endoscope was used in combination with laser/mechanical cholelithotripsy, mechanical retrograde, and balloon-assisted anterograde cholelithotomy to remove gallstones and common bile duct stones. Surgical contraindications ranged from cardiopulmonary disease to morbid obesity to neoplastic processes. Timing and number of interventions, as well as technical and clinical successes, were assessed. RESULTS The median time interval from cholecystostomy catheter placement to cholelithotripsy was 58 days, after an average of 2 tube exchange procedures. Technical and clinical success were achieved in all patients (stone-free gallbladder and cholecystostomy tube removal). On average, three sessions of cholecystoscopy and laser and mechanical cholelithotripsy were required for complete gallstone extraction. The mean interval time between the first cholelithotripsy session and removal of cholecystostomy was 71.8±60.8 days. There were neither major nor minor procedure-related complications. CONCLUSION Percutaneous cholecystoscopy using the LithoVue endoscope, in combination with laser/ mechanical cholelithotripsy and mechanical cholelithotomy, is feasible, safe, well-tolerated, and was able to remove the cholecystostomy tube in the patients with contraindication to cholecystectomy.


Assuntos
Colecistite Aguda , Cálculos Biliares , Colecistite Aguda/diagnóstico por imagem , Colecistite Aguda/cirurgia , Estudos de Viabilidade , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/cirurgia , Humanos , Lasers , Estudos Retrospectivos , Resultado do Tratamento
18.
Methods Mol Biol ; 2536: 369-380, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35819614

RESUMO

In the past 20 years, laser microdissection (LMD) technology has been widely applied to plant tissues, allowing to obtain new information on the role of different cell-type populations during plant development and interactions, including plant-pathogen interactions. The application of a LMD approach allowed verifying the response of plant and pathogen during the progression of the infection in different cell types, focusing both on gene expression in host plants and pathogens. Here, a protocol to apply the LMD approach to study plant and fungal transcript profiles in different cell-type populations is described in detail, from the biological material preparation to RNA extraction and gene expression analyses.


Assuntos
Fungos , Plantas , Fungos/genética , Microdissecção e Captura a Laser , Lasers , Plantas/metabolismo
19.
J Drugs Dermatol ; 21(7): 773-775, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35816072

RESUMO

Pediatric vitiligo is often challenging to treat. Children with vitiligo experience stigma, bullying, and emotional distress. The long-term outcome of therapeutics used to treat pediatric vitiligo has been poorly documented in the literature. It is, therefore, hard to counsel patients on the expected long-term results of therapy. We sought to address outcomes in pediatric vitiligo treated with a 308-nm laser. An IRB-exempt chart review was conducted in June of 2016 of children undergoing active 308-nm laser in the first half of 2016. Demographic data, location of disease, therapeutic parameters of the 308-nm laser, and outcomes were recorded at that time. In 2021, the long-term outcomes were analyzed through chart review addressing pigmentation retained at later office visits. Initial repigmentation was noted in 86.7% of the face, 80% of the body, and 61.7% of the extremities. An average of 3.38 years of follow-up was recorded. Scoring extent of vitiligo using 18 site-scoring was helpful in identifying individuals who are less likely to respond to 308-nm laser, but needs broader evaluation. During that time, repigmentation was noted to be retained in 80% of facial, 40% of the body, and 20% of extremity lesions. Pediatric vitiligo responds well to the 308-nm laser, with the best retention of repigmentation for facial lesions. Patients and parents should be counseled on the likelihood of long-term retention of repigmentation and regarding the need for the ongoing management of vitiligo even after repigmentation is initially achieved after 308-nm laser therapy. J Drugs Dermatol. 2022;21(7):773-775. doi:10.36849/JDD.6895.


Assuntos
Terapia a Laser , Terapia com Luz de Baixa Intensidade , Vitiligo , Criança , Humanos , Lasers , Terapia com Luz de Baixa Intensidade/métodos , Pigmentação da Pele , Resultado do Tratamento , Vitiligo/diagnóstico , Vitiligo/radioterapia
20.
Chin Med Sci J ; 37(2): 159-163, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35796340

RESUMO

A 2-year-old girl was diagnosed as Weill-Marchesani syndrome with typical systemic features of short stature, short and stubby hands and feet, language disorders and mental retardation. He developed bilateral angle closure glaucoma, ectopia lentis and suffered visual loss from the ocular features of Weill-Marchesani syndrome. The child was successfully treated by combined CO2 laser-assisted sclerectomy surgery and trabeculectomy.


Assuntos
Glaucoma , Trabeculectomia , Síndrome de Weill-Marchesani , Dióxido de Carbono , Criança , Pré-Escolar , Feminino , Glaucoma/etiologia , Glaucoma/cirurgia , Humanos , Lasers , Masculino
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