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1.
Biochem Soc Trans ; 50(3): 1057-1067, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35695670

RESUMO

Structural Biology has moved beyond the aim of simply identifying the components of a cellular subsystem towards analysing the dynamics and interactions of multiple players within a cell. This focal shift comes with additional requirements for the analytical tools used to investigate these systems of increased size and complexity, such as Native Mass Spectrometry, which has always been an important tool for structural biology. Scientific advance and recent developments, such as new ways to mimic a cell membrane for a membrane protein, have caused established methods to struggle to keep up with the increased demands. In this review, we summarize the possibilities, which Laser Induced Liquid Bead Ion Desorption (LILBID) mass spectrometry offers with regard to the challenges of modern structural biology, like increasingly complex sample composition, novel membrane mimics and advanced structural analysis, including next neighbor relations and the dynamics of complex formation.


Assuntos
Lasers , Proteínas de Membrana , Íons , Espectrometria de Massas/métodos , Proteínas de Membrana/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
2.
Chemosphere ; 303(Pt 2): 135168, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35649446

RESUMO

Plastic waste is an environmental problematic, not only because of its own contamination, but also because it can act as a vector for other pollutants, particularly metals. In this work, taking advantage of the sensitivity of the LIBS technique, the presence of copper in plastics and microplastics present in a stream that receives effluents from a medium-sized city was determined. The influence of the digestion process on the collected samples was analyzed. On the other hand, copper retention in commonly used plastics submerged in stream water and in a solution prepared in the laboratory was analyzed. This study confirms that both macroplastics and microplastics collected from a stream that receives effluents from a city, can retain copper.


Assuntos
Microplásticos , Poluentes Químicos da Água , Cobre , Monitoramento Ambiental , Lasers , Plásticos , Análise Espectral , Poluentes Químicos da Água/análise
3.
Transl Vis Sci Technol ; 11(6): 15, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704328

RESUMO

Purpose: To investigate the correlation between laser speckle flowgraphy (LSFG) signals and the quantitative metrics derived from optical coherence tomography (OCT) in normal eyes. Methods: LSFG, OCT, and OCT angiography (OCTA) imaging were performed on normal participants using a custom-designed LSFG system and a commercial swept-source OCT system. Mean (PWM) and amplitude (PWA) of the LSFG pulse waveform were selected to quantify the LSFG signals. Retinal and choroidal maps were obtained using the standard 6 × 6 mm OCT and OCTA scans. Structural and vascular metrics maps, including thickness, vessel area density, vessel skeleton density, and vessel diameter index of the retina, and choroidal thickness (CT), choroidal vessel volume (CVV) and choroidal vessel index (CVI), were employed to quantify the retinal and choroidal properties. Correlation analysis was then performed between the LSFG, retinal, and choroidal metrics maps. Results: Twelve healthy participants aged 23 to 36 years were enrolled in this study. The spatial distribution of the PWM and PWA values was highly correlated with that of the CT and CVV metrics. On average, Spearman correlation coefficients (ρ) were 0.80 and 0.78 (all P < 0.001) for the correlations between PWM and CT and CVV, respectively, and were 0.61 and 0.63 (all P < 0.05) for the correlations between PWA and CT and CVV, respectively. In comparison, both PWM and PWA were generally weak or not correlated with all the retinal metrics and CVI. Conclusions: LSFG signals were positively correlated with the choroidal thickness and vessel volume, suggesting choroidal blood flows dominate the LSFG signals at the area absent of large retinal vessels. Translational Relevance: This study illustrates the dominant source of the LSFG signals in the eye.


Assuntos
Benchmarking , Tomografia de Coerência Óptica , Corioide/irrigação sanguínea , Corioide/diagnóstico por imagem , Humanos , Lasers , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos
4.
Transpl Int ; 35: 10455, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711322

RESUMO

Endogenous production of carbon monoxide (CO) is affected by inflammatory phenomena and ischemia-reperfusion injury. Precise measurement of exhaled endogenous CO (eCO) is possible thanks to a laser spectrometer (ProCeas® from AP2E company). We assessed eCO levels of human lung grafts during the normothermic Ex-Vivo Lung Perfusion (EVLP). ProCeas® was connected in bypass to the ventilation circuit. The surgical team took the decision to transplant the lungs without knowing eCO values. We compared eCO between accepted and rejected grafts. EVLP parameters and recipient outcomes were also compared with eCO values. Over 7 months, eCO was analyzed in 21 consecutive EVLP grafts. Two pairs of lungs were rejected by the surgical team. In these two cases, there was a tendency for higher eCO values (0.358 ± 0.52 ppm) compared to transplanted lungs (0.240 ± 0.76 ppm). During the EVLP procedure, eCO was correlated with glucose consumption and lactate production. However, there was no association of eCO neither with edema formation nor with the PO2/FiO2 ratio per EVLP. Regarding post-operative data, every patient transplanted with grafts exhaling high eCO levels (>0.235 ppm) during EVLP presented a Primary Graft Dysfunction score of 3 within the 72 h post-transplantation. There was also a tendency for a longer stay in ICU for recipients with grafts exhaling high eCO levels during EVLP. eCO can be continuously monitored during EVLP. It could serve as an additional and early marker in the evaluation of the lung grafts providing relevant information for post-operative resuscitation care.


Assuntos
Expiração , Transplante de Pulmão , Humanos , Lasers , Pulmão , Transplante de Pulmão/métodos , Perfusão/métodos
5.
Sensors (Basel) ; 22(12)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35746392

RESUMO

As innovative technologies emerge, extensive research has been undertaken to develop new structural health monitoring procedures. The current methods, involving on-site visual inspections, have proven to be costly, time-consuming, labor-intensive, and highly subjective for assessing the safety and integrity of civil infrastructures. Mobile and stationary LiDAR (Light Detection and Ranging) devices have significant potential for damage detection, as the scans provide detailed geometric information about the structures being evaluated. This paper reviews the recent developments for LiDAR-based structural health monitoring, in particular, for detecting cracks, deformation, defects, or changes to structures over time. In this regard, mobile laser scanning (MLS) and terrestrial laser scanning (TLS), specific to structural health monitoring, were reviewed for a wide range of civil infrastructure systems, including bridges, roads and pavements, tunnels and arch structures, post-disaster reconnaissance, historical and heritage structures, roofs, and retaining walls. Finally, the existing limitations and future research directions of LiDAR technology for structural health monitoring are discussed in detail.


Assuntos
Lasers , Luz
6.
Sci Rep ; 12(1): 10535, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732689

RESUMO

The intraocular pressure (IOP)-lowering mechanisms of micropulse laser trabeculoplasty (MLT) remain unclear. The present study was performed to investigate the mechanism of action of MLT, and to determine whether the pigmentation intensity of trabecular meshwork (TM) cells is associated with the treatment effects. Primary human TM cells were exposed to melanin granules to artificially introduce different levels of pigmentation. Micropulse (MP) laser irradiation was performed, and interleukin (IL)-1α/ß, matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs), and extracellular matrix (ECM) protein expression were evaluated by RT-qPCR and immunocytochemistry. IL-1α/ß and MMP-1, -3, and -9 mRNA expression were significantly upregulated at 4 and 24 h after MP laser irradiation, respectively, but there were no significant changes in TIMP expression. The extent of these upregulation was greater in cells with strong pigmentation intensity. Protein expressions of fibronectin and collagen I were significantly decreased in cells with strong staining intensity. These results suggested that MP laser irradiation alter the MMP/TIMP ratio and enhance ECM turnover, resulting in increased outflow of aqueous humor. The pigmentation intensity of the TM tissues may affect the treatment efficacy of MLT, because TM cells with strong staining intensity showed a significantly enhanced response to MP laser irradiation.


Assuntos
Malha Trabecular , Trabeculectomia , Células Cultivadas , Proteínas da Matriz Extracelular/metabolismo , Humanos , Pressão Intraocular , Lasers , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Pigmentação , Inibidores Teciduais de Metaloproteinases/genética , Malha Trabecular/metabolismo
7.
Methods Mol Biol ; 2505: 45-58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35732935

RESUMO

The surface-assisted laser desorption/ionization (SALDI) technique uses inorganic materials to aid desorption and ionization of molecules. SALDI is suitable for analyzing small molecules due to the absence of interfering signals in the low m/z range originating from the organic matrix. Imaging mass spectrometry (IMS) is a versatile imaging approach with high spatial resolution for analyzing various molecular species, but its application depends heavily on the ionization method. We have developed a functionalized titanium dioxide (TiO2) nanowire as a solid substrate for SALDI-MS detection of low-molecular-weight molecules. We apply this novel substrate for imprinting fragile specimens such as petals and further SALDI-IMS analysis. The TiO2 nanowire substrate is prepared from a commercial Ti plate by a hydrothermal process and subsequently chemically modified to improve the quality and selectivity of imprinting as well as the sensitivity of SALDI-IMS analysis. Here, the functionalized TiO2 nanowire substrate is applied to visualize the distribution of vinca alkaloids in the petal of Madagascar periwinkle (Catharanthus roseus).


Assuntos
Catharanthus , Alcaloides de Vinca , Diagnóstico por Imagem/métodos , Lasers , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
8.
Biosensors (Basel) ; 12(6)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35735545

RESUMO

Wearable sweat sensors are a rapidly rising research area owing to their convenience for personal healthcare and disease diagnosis in a real-time and noninvasive manner. However, the fast and scalable fabrication of flexible electrodes remains a major challenge. Here, we develop a wearable epidermal sensor for multiplexed sweat analysis based on the laser-induced graphene (LIG) technique. This simple and mask-free technique allows the direct manufacturing of graphene electrode patterns on commercial polyimide foils. The resulting LIG devices can simultaneously monitor the pH, Na+, and K+ levels in sweat with the sensitivities of 51.5 mV/decade (pH), 45.4 mV/decade (Na+), and 43.3 mV/decade (K+), respectively. Good reproducibility, stability, and selectivity are also observed. On-body testing of the LIG-based sensor integrated with a flexible printed circuit board during stationary cycling demonstrates its capability for real-time sweat analysis. The concentrations of ions can be remotely and wirelessly transmitted to a custom-developed smartphone application during the period in which the sensor user performs physical activities. Owing to the unique advantages of LIG technique, including facile fabrication, mass production, and versatile, more physiological signals (glucose, uric acid, tyrosine, etc.) could be easily expanded into the LIG-based wearable sensors to reflect the health status or clinical needs of individuals.


Assuntos
Técnicas Biossensoriais , Grafite , Dispositivos Eletrônicos Vestíveis , Humanos , Íons , Lasers , Reprodutibilidade dos Testes , Suor
9.
ACS Appl Mater Interfaces ; 14(25): 28683-28696, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35704779

RESUMO

Innovative therapies are urgently needed to combat cancer. Thermal ablation of tumor cells is a promising minimally invasive treatment option. Infrared light can penetrate human tissues and reach superficial malignancies. MXenes are a class of 2D materials that consist of carbides/nitrides of transition metals. The transverse surface plasmons of MXenes allow for efficient light absorption and light-to-heat conversion, making MXenes promising agents for photothermal therapy (PTT). To date, near-infrared (NIR) light lasers have been used in PTT studies explicitly in a continuous mode. We hypothesized that pulsed NIR lasers have certain advantages for the development of tailored PTT treatment targeting tumor cells. The pulsed lasers offer a wide range of controllable parameters, such as power density, duration of pulses, pulse frequency, and so on. Consequently, they can lower the total energy applied and enable the ablation of tumor cells while sparing adjacent healthy tissues. We show for the first time that a pulsed 1064 nm laser could be employed for selective ablation of cells loaded with Ti3C2Tx MXene. We demonstrate both low toxicity and good biocompatibility of this MXene in vitro, as well as a favorable safety profile based on the experiments in vivo. Furthermore, we analyze the interaction of MXene with cells in several cell lines and discuss possible artifacts of commonly used cellular metabolic assays in experiments with MXenes. Overall, these studies provide a basis for the development of efficient and safe protocols for minimally invasive therapies for certain tumors.


Assuntos
Hipertermia Induzida , Linhagem Celular Tumoral , Humanos , Hipertermia Induzida/métodos , Raios Infravermelhos , Lasers , Terapia Fototérmica
10.
J Phys Chem Lett ; 13(25): 5845-5853, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35727076

RESUMO

The Coulomb explosion of tribromomethane (bromoform, CHBr3) induced by 28 fs near-infrared laser pulses is investigated by three-dimensional coincidence ion momentum imaging. We focus on the fragmentation into three, four, and five ionic fragments measured in coincidence and present different ways of visualizing the three-dimensional momentum correlations. We show that the experimentally observed momentum correlations for 4- and 5-fold coincidences are well reproduced by classical Coulomb explosion simulations and contain information about the structure of the parent molecule that could be used to differentiate structural isomers formed, for example, in a pump-probe experiment. Our results thus provide a clear path toward visualizing structural dynamics in polyatomic molecules by strong-field-induced Coulomb explosion imaging.


Assuntos
Lasers , Trialometanos , Íons
11.
Sci Rep ; 12(1): 10964, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35768623

RESUMO

This study was performed to utilize transnasal Sphenopalatine Ganglion (SPG) block for pain reliving during panretinal photocoagulation (PRP) in diabetic patients with diabetic retinopathy. This pre and post interventional study was performed on 20 patients with proliferative diabetic retinopathy. The first PRP treatment session of all the patients is performed with no transnasal SPG block, but before holding the second session, all the patients underwent transnasal SPG block and pain levels during and after PRP were compared to each other. Before the transnasal SPG block, each nostril of all the cases was inspected for finding any obstruction in each PRP session. Transnasal SPG block was also performed in with 2% lidocaine. The mean age of the included cases was 52.84 ± 8.62 years old (from 36 to 72 years old). All the cases underwent two PRP lasers treatment sessions with the same characteristic (spot size, power and duration) for each patient. In the first and second PRP treatment sessions, the mean NRS scores were obtained immediately after the PRP laser (8.4 vs. 4.2), 15 min (8.2 vs. 4.2), 1 h (8.0 vs. 4.1), and 24 h (5.4 vs. 3.6) after the PRP respectively. The mean NRS scores significantly reduced during the second PRP treatment session compared to the first session (p < 0.001). Transnasal SPG block is a safe and effective strategy used for relieving pain caused by the PRP laser treatment in patients with diabetic retinopathy.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Bloqueio do Gânglio Esfenopalatino , Adulto , Idoso , Diabetes Mellitus/etiologia , Retinopatia Diabética/cirurgia , Humanos , Fotocoagulação a Laser/efeitos adversos , Lasers , Pessoa de Meia-Idade , Dor/etiologia
12.
J Acupunct Meridian Stud ; 15(3): 189-193, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35770549

RESUMO

Carpal tunnel syndrome (CTS) is disease that gives burdens for many countries, with a few choices for the management such as drugs or surgery, each has side effects that decrease the quality of life. Acupuncture is proven to be an effective treatment for pain and can restore nerve functions, and laser acupuncture is one of the modalities. This study aims to assess the effectiveness of laser acupuncture with total sample of 3 patients (6 wrists) mostly with tingling sensations and the outcomes are Boston questionnaire (BCTQ), visual analogue scale (VAS), Tinel sign, Phalen sign, and parameters of nerve conduction study (NCS). Acupuncture points used here are PC6, PC7, EXUE9, and LI4. The results show a decrease in NCS grades for 3 wrists, all wrists have BCTQ score improvements, a decrease in VAS, but no significant improvement in Tinel and Phalen signs. It is concluded that laser acupuncture can be used as a treatment option for the management of carpal tunnel syndrome.


Assuntos
Terapia por Acupuntura , Síndrome do Túnel Carpal , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Síndrome do Túnel Carpal/terapia , Humanos , Lasers , Qualidade de Vida
13.
Anal Chem ; 94(23): 8194-8201, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35658398

RESUMO

Many studies have demonstrated that tissue phenotyping (tissue typing) based on mass spectrometric imaging data is possible; however, comprehensive studies assessing variation and classifier transferability are largely lacking. This study evaluated the generalization of tissue classification based on Matrix Assisted Laser Desorption/Ionization (MALDI) mass spectrometric imaging (MSI) across measurements performed at different sites. Sections of a tissue microarray (TMA) consisting of different formalin-fixed and paraffin-embedded (FFPE) human tissue samples from different tumor entities (leiomyoma, seminoma, mantle cell lymphoma, melanoma, breast cancer, and squamous cell carcinoma of the lung) were prepared and measured by MALDI-MSI at different sites using a standard protocol (SOP). Technical variation was deliberately introduced on two separate measurements via a different sample preparation protocol and a MALDI Time of Flight mass spectrometer that was not tuned to optimal performance. Using standard data preprocessing, a classification accuracy of 91.4% per pixel was achieved for intrasite classifications. When applying a leave-one-site-out cross-validation strategy, accuracy per pixel over sites was 78.6% for the SOP-compliant data sets and as low as 36.1% for the mistuned instrument data set. Data preprocessing designed to remove technical variation while retaining biological information substantially increased classification accuracy for all data sets with SOP-compliant data sets improved to 94.3%. In particular, classification accuracy of the mistuned instrument data set improved to 81.3% and from 67.0% to 87.8% per pixel for the non-SOP-compliant data set. We demonstrate that MALDI-MSI-based tissue classification is possible across sites when applying histological annotation and an optimized data preprocessing pipeline to improve generalization of classifications over technical variation and increasing overall robustness.


Assuntos
Carcinoma de Células Escamosas , Adulto , Diagnóstico por Imagem , Humanos , Lasers , Inclusão em Parafina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
14.
Sci Rep ; 12(1): 9802, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697840

RESUMO

A prospective study was conducted on 33 eyes of 33 patients with open-angle glaucoma who underwent trabeculectomy to investigate hemodynamic changes in the temporal optic nerve head (ONH) and peripapillary atrophy (PPA) after trabeculectomy. Laser speckle flowgraphy of ONH and PPA was performed at baseline and at 1, 3, and 6 months postoperatively. The waveforms of the mean blur rate in the tissue area (MT) in the temporal ONH, ßPPA (with Bruch's membrane), and γPPA (without Bruch's membrane) were evaluated. Mean intra-ocular pressure (IOP) decreased from 19.1 ± 0.8 to 8.5-9.6 ± 0.7 mmHg at postoperative visits. The average MT in the ßPPA region increased significantly at all postoperative time points, whereas those in the ONH and γPPA regions remained unchanged. The blowout score (BOS) increased significantly, and the resistivity index decreased significantly at all time points in all regions, which was associated with decreased IOP. The current study showed two novel findings: MT increased after trabeculectomy only in ßPPA, where the choroid was present. IOP decrease-associated BOS increase occurred postoperatively in all regions, which indicates that IOP reduction may decrease vascular transmural pressure and contribute to stable blood flow uniformly, despite structural differences between the regions.


Assuntos
Glaucoma de Ângulo Aberto , Disco Óptico , Trabeculectomia , Atrofia/patologia , Humanos , Pressão Intraocular , Lasers , Disco Óptico/patologia , Estudos Prospectivos , Tomografia de Coerência Óptica , Trabeculectomia/efeitos adversos
15.
Mikrochim Acta ; 189(7): 253, 2022 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-35689150

RESUMO

A series of functional metal-organic frameworks (MOFs) were facilely prepared through an one-pot procedure or post-synthetic modification strategy and used as matrices in laser desorption ionization mass spectrometry (LDI-MS). Compared with traditional organic matrices and other MOFs, maltose-functional MOF MIL-101-maltose demonstrated ultrahigh ionization efficiency, free matrix background, uniform crystallization, and good dispersibility. A simple, general, and efficient LDI-MS platform was developed for rapid detection of various small biomolecules using MIL-101-maltose as matrix, providing several advantages including low sample consumption of 500 nL, short analysis time of few seconds, strong salt tolerance (500 mM NaCl), and satisfactory reproducibility. The MIL-101-maltose matrix was used for serum glucose determination and successfully distinguished the diabetic patients from the healthy controls. This work provides a generic LDI-MS platform for fast determination of small biomolecules with high potential in clinical diagnosis and disease monitoring.


Assuntos
Estruturas Metalorgânicas , Humanos , Lasers , Maltose , Estruturas Metalorgânicas/química , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
16.
Mikrochim Acta ; 189(7): 254, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697907

RESUMO

Organophosphorus pesticides are widely used in industrial agriculture and have been associated with water pollution and negative impacts on local ecosystems and communities. There is a need for testing technologies to detect the presence of pesticide residues in water sources, especially in developing countries where access to standard laboratory methods is cost prohibitive. Herein, we outline the development of a facile electrochemical sensor for amperometric determination of organophosphorus pesticides in environmental water samples. A three-electrode system was fabricated via UV laser-inscribing on a polyimide film. The working electrode was functionalized with copper nanoparticles with affinity toward organophosphate compounds. The sensor showed a limit of detection (LOD) of 3.42 ± 1.69 µM for glyphosate, 7.28 ± 1.20 µM for glufosinate, and 17.78 ± 7.68 µM for aminomethylphosphonic acid (AMPA). Sensitivity was highest for glyphosate (145.52 ± 36.73 nA⋅µM-1⋅cm-2) followed by glufosinate (56.98 ± 10.87 nA⋅µM-1⋅cm-2), and AMPA (30.92 ± 8.51 nA⋅µM-1⋅cm-2). The response of the sensor is not significantly affected by the presence of several ions and organic molecules commonly present in natural water samples. The developed sensor shows promising potential for facilitating environmental monitoring of organophosphorus pesticide residues, which is a current need in several parts of the world.


Assuntos
Resíduos de Praguicidas , Praguicidas , Ecossistema , Lasers , Compostos Organofosforados/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Água/química
17.
Biomed Mater ; 17(4)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35748526

RESUMO

Titanium dioxide (TiO2), as one of the titanium (Ti)-based implants, holds a promise for a variety of anti-bacterial application in medical research. In the current study, a functional molybdenum disulfide (MoS2)/polydopamine (PDA)-LL-37 coating on titanium dioxide (TiO2) implant was prepared. Anodic oxidation and hydrothermal treatment was given to prepare TiO2nanotubes-MoS2/PDA-LL-37 (T-M/P-L). Thein vitroosteogenic effect of T-M/P-L was evaluated by measuring mesenchymal stem cell (MSC) adhesion, proliferation, alkaline phosphatase (ALP) activity, extracellular matrix (ECM) mineralization, collagen secretion and osteoblast-specific messenger RNAs (mRNAs) expression. The determination on the anti-bacterial ability of T-M/P-L was followed. Furthermore, the ability of T-M/P-L to promote bone formationin vivowas evaluated. Near-infrared (NIR) laser irradiation exposure enabled the T-M/P-L coating-endowed Ti substrates to hold effective anti-bacterial ability. T-M/P-L promoted the adhesion and proliferation of MSCs. In addition, an increase was witnessed regarding the ALP activity, collagen secretion and ECM mineralization, along with the expression of runt-related transcription factor 2, ALP and osteocalcin in the presence of T-M/P-L. Additionally, T-M/P-L could stimulate endothelial cells to secrete vascular endothelial growth factor (VEGF) and promote capillary-like tubule formation. Upon NIR laser irradiation exposure, T-M/P-L not only exhibited efficientin vivoanti-bacterial activity but also facilitated new bone formation. Collectively, T-M/P-L had enhanced anti-bacterial and osteogenic activity under NIR laser irradiation.


Assuntos
Nanotubos , Osteogênese , Diferenciação Celular , Colágeno/metabolismo , Células Endoteliais , Indóis , Raios Infravermelhos , Lasers , Molibdênio/metabolismo , Molibdênio/farmacologia , Osteoblastos/metabolismo , Polímeros , Titânio/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
J Phys Chem Lett ; 13(24): 5413-5423, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35679146

RESUMO

Femtosecond laser pulses readily produce coherent quantum beats in transient-absorption spectra. These oscillatory signals often arise from molecular vibrations and therefore may contain information about the excited-state potential energy surface near the Franck-Condon region. Here, by fitting the measured spectra of two laser dyes to microscopic models of femtosecond coherence spectra (FCS) arising from molecular vibrations, we classify coherent quantum-beat signals as fundamentals or overtones and quantify their Huang-Rhys factors and anharmonicity values. We discuss the extracted Huang-Rhys factors in the context of quantum-chemical computations. This work solidifies the use of FCS for analysis of coherent quantum beats arising from molecular vibrations, which will aid studies of molecular aggregates and photosynthetic proteins.


Assuntos
Fotossíntese , Vibração , Lasers
19.
Mikrochim Acta ; 189(7): 259, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35704127

RESUMO

A rapid and effective technique has been develped for the fabrication of sensor-active copper-based materials on the surface of such flexible polymers as terephthalate, polyethylene naphthalate, and polyimide using the method of laser surface modification. For this purpose, we optimized the polymer surface activation parameters using laser sources with a picosecond pulse duration for subsequent selective metallization within the activated region. Furthermore, the fabricated copper structures were modified with gold nanostructures and by electrochemical passivation to produce copper-gold and oxide-containing copper species, respectively. As a result, in comparison with pure copper electrodes, these composite materials exhibit much better electrocatalytic performance concerning the non-enzymatic identification of biologically important disease markers such as glucose, hydrogen peroxide, and dopamine.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Técnicas Biossensoriais/métodos , Cobre/química , Técnicas Eletroquímicas/métodos , Ouro/química , Lasers
20.
Twin Res Hum Genet ; 25(1): 45-49, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35644997

RESUMO

The aim of this study was to describe the neonatal management and outcome in monochorionic twins with twin-to-twin transfusion syndrome (TTTS) not treated with fetoscopic laser surgery. All consecutive live-born neonates with TTTS managed at our center between 2002 and 2021 were included in this retrospective study. Neonatal outcome was assessed in 44 twin pairs with TTTS not treated with laser (nonlaser group) compared to a control group of 88 twin pairs with TTTS successfully treated with laser (laser group), matched for gestational age at birth. Primary outcome was adverse neonatal outcome, a composite outcome including neonatal mortality or severe neonatal morbidity. The incidence of adverse neonatal outcome in the nonlaser group and laser group was 30% (26/88) and 11% (19/176), respectively (relative risk = 3.46, 95% CI [1.79, 6.71]). In the nonlaser group, 11% had necrotizing enterocolitis (vs. 2% in the laser group) and 24% had hypotension (vs. 10% in the laser group). Recipients in the nonlaser group had, compared to recipients in the laser group, significantly more severe cerebral injury (18% vs. 5%) and more polycythemia at birth (21% vs. 1%). Donors in the nonlaser group had, compared to donors in the laser group, more severe growth restriction (71% vs 42%), renal failure (11% vs 1%), and anemia at birth (25% vs. 7%). Thus, the risk for neonatal mortality and/or severe morbidity is three-fold higher in TTTS not treated with laser than in TTTS treated with laser, which highlights the fact that these neonates with TTTS are very sick at birth, requiring accurate and prompt intensive treatment.


Assuntos
Transfusão Feto-Fetal , Terapia a Laser , Feminino , Transfusão Feto-Fetal/cirurgia , Fetoscopia , Humanos , Recém-Nascido , Lasers , Gravidez , Estudos Retrospectivos
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