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1.
Mikrochim Acta ; 191(6): 361, 2024 06 01.
Article En | MEDLINE | ID: mdl-38822891

A one-shot CO2 laser-based strategy to generate conductive reduced graphene oxide (rGO) decorated with nanoceria (nCe) is proposed. The 2D/0D rGO-nCe films, integrated as catalytic sensing layers in paper-based sensors, were employed for on-site monitoring of indoor fogging treatments against Listeria monocytogenes (Lm), a ubiquitous pathogenic bacterium. The rGO-nCe laser-assisted synthesis was optimized to preserve the rGO film morphological and electron-transfer features and simultaneously integrate catalytic nCe. The films were characterized by microscopical (SEM), spectroscopical (EDX, Raman, and FTIR), and electrochemical techniques. The most performing film was integrated into a nitrocellulose substrate, and the complete sensor was assembled via a combination of xurography and stencil printing. The rGO-nCe sensor's catalytic activity was proved toward the detection of H2O2, obtaining sensitive determination (LOD = 0.3 µM) and an extended linear range (0.5-1500 µM). Eventually, the rGO-nCe sensor was challenged for the real-time continuous monitoring of hydrogen peroxide aerosol during no-touch fogging treatment conducted following the EU's recommendation for biocidal product use. Treatment effectiveness was proved toward three Lm strains characterized by different origins, i.e., type strain ATCC 7644, clinical strain 338, and food strain 641/6II. The sensor allows for discrimination and quantification treatments at different environmental biocidal amounts and fogging times, and correlates with the microbiological inhibition, promoting the proposed sensor as a useful tool to modulate and monitor no-touch treatments.


Disinfection , Graphite , Hydrogen Peroxide , Lasers , Listeria monocytogenes , Paper , Graphite/chemistry , Hydrogen Peroxide/chemistry , Listeria monocytogenes/drug effects , Listeria monocytogenes/isolation & purification , Disinfection/methods , Cerium/chemistry , Limit of Detection , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Catalysis
2.
J Biomed Opt ; 29(6): 067001, 2024 Jun.
Article En | MEDLINE | ID: mdl-38826808

Significance: In the realm of cerebrovascular monitoring, primary metrics typically include blood pressure, which influences cerebral blood flow (CBF) and is contingent upon vessel radius. Measuring CBF noninvasively poses a persistent challenge, primarily attributed to the difficulty of accessing and obtaining signal from the brain. Aim: Our study aims to introduce a compact speckle contrast optical spectroscopy device for noninvasive CBF measurements at long source-to-detector distances, offering cost-effectiveness, and scalability while tracking blood flow (BF) with remarkable sensitivity and temporal resolution. Approach: The wearable sensor module consists solely of a laser diode and a board camera. It can be easily placed on a subject's head to measure BF at a sampling rate of 80 Hz. Results: Compared to the single-fiber-based version, the proposed device achieved a signal gain of about 70 times, showed superior stability, reproducibility, and signal-to-noise ratio for measuring BF at long source-to-detector distances. The device can be distributed in multiple configurations around the head. Conclusions: Given its cost-effectiveness, scalability, and simplicity, this laser-centric tool offers significant potential in advancing noninvasive cerebral monitoring technologies.


Cerebrovascular Circulation , Equipment Design , Spectrum Analysis , Humans , Cerebrovascular Circulation/physiology , Spectrum Analysis/instrumentation , Cost-Benefit Analysis , Reproducibility of Results , Wearable Electronic Devices , Signal-To-Noise Ratio , Lasers , Brain/blood supply , Brain/diagnostic imaging , Brain/physiology , Laser Speckle Contrast Imaging/instrumentation
3.
Med Eng Phys ; 127: 104170, 2024 May.
Article En | MEDLINE | ID: mdl-38692767

Recently, functional Near-Infrared Spectroscopy (fNIRS) was applied to obtain, non-invasively, the human peri­spinal Neuro-Vascular Response (NVR) under a non-noxious electrical stimulation of a peripheral nerve. This method allowed the measurements of changes in the concentration of oxyhemoglobin (O2Hb) and deoxyhemoglobin (HHb) from the peri­spinal vascular network. However, there is a lack of clarity about the potential differences in perispinal NVR recorded by the different fNIRS technologies currently available. In this work, the two main noninvasive fNIRS technologies were compared, i.e., LED and LASER-based. The recording of the human peri­spinal NVR induced by non-noxious electrical stimulation of a peripheral nerve was recorded simultaneously at C7 and T10 vertebral levels. The amplitude, rise time, and full width at half maximum duration of the perispinal NVRs were characterized in healthy volunteers and compared between both systems. The main difference was that the LED-based system shows about one order of magnitude higher values of amplitude than the LASER-based system. No statistical differences were found for rise time and for duration parameters (at thoracic level). The comparison of point-to-point wave patterns did not show significant differences between both systems. In conclusion, the peri­spinal NRV response obtained by different fNIRS technologies was reproducible, and only the amplitude showed differences, probably due to the power of the system which should be considered when assessing the human peri­spinal vascular network.


Lasers , Spectroscopy, Near-Infrared , Spinal Cord , Humans , Spectroscopy, Near-Infrared/methods , Male , Spinal Cord/blood supply , Spinal Cord/diagnostic imaging , Spinal Cord/physiology , Adult , Female , Young Adult , Electric Stimulation , Hemoglobins/analysis , Hemoglobins/metabolism
4.
Anal Chim Acta ; 1306: 342617, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38692789

BACKGROUND: Alpha-fetoprotein (AFP) is a fetal protein that can indicate congenital anomalies such as Down syndrome and spinal canal blockage when detected at abnormal levels in pregnant women. Current AFP detection methods rely on invasive blood or serum samples, which require sophisticated equipment. From the many solutions proposed, colorimetric paper-based assays excel in point-of-care settings. The concept of paper-based ELISA (p-ELISA) enhances traditional methods, aligning with the ASSURED criteria for diagnostics in resource-limited regions. Despite success in microfluidic paper-based assay devices, laser printing remains underexplored for p-ELISA. Additionally, modifying the paper surface provides an additional layer of sensitivity enhancement. RESULTS: In this study, we developed a novel laser-printed paper-based ELISA (LP-pELISA) for rapid, sensitive, and noninvasive detection of AFP in saliva samples. The LP-pELISA platform was fabricated by printing hydrophobic barriers on filter paper using a laser printer, followed by depositing hydroxyapatite (HAp) as an immobilization material for the antibodies. The colorimetric detection was achieved using AuNPs functionalized with anti-AFP antibodies and silver nitrate enhancement. The LP-pELISA exhibited a linear response for AFP detection in both buffer and saliva samples over a range of 1.0-800 ng mL-1, with a limit of detection (LOD) reaching 1.0 ng mL-1. The assay also demonstrated good selectivity, repeatability, reproducibility, and stability. The LP-pELISA was further validated by testing spiked human saliva samples, showing its potential for point-of-care diagnosis of congenital disabilities. SIGNIFICANCE: The LP-pELISA is a noninvasive platform showcasing simplicity, cost-effectiveness, and user-friendliness, utilizing laser printing, hydroxyapatite modification, and saliva samples to efficiently detect AFP. Beyond its application for AFP, this method's versatility extends to other biomarkers, positioning it as a catalyst for the evolution of paper-based biosensors. The LP-pELISA holds promise as a transformative tool for point-of-care diagnostics, fostering advancements in healthcare with its innovative technology.


Colorimetry , Durapatite , Enzyme-Linked Immunosorbent Assay , Lasers , Paper , Saliva , alpha-Fetoproteins , Humans , Saliva/chemistry , Durapatite/chemistry , alpha-Fetoproteins/analysis , Printing , Gold/chemistry , Limit of Detection , Antibodies, Immobilized/immunology , Antibodies, Immobilized/chemistry
5.
Stomatologiia (Mosk) ; 103(2): 86-90, 2024.
Article Ru | MEDLINE | ID: mdl-38741541

The paper presents an overview of modern scientific data on the study of the effect of laser radiation on biological tissues of the mouth in the therapeutic treatment of dental diseases. The use of lasers in the treatment of dental caries and its complications, non-carious lesions of hard dental tissues, as well as the use of lasers in the treatment of periodontal diseases and aesthetic restoration of teeth is considered.


Laser Therapy , Humans , Laser Therapy/methods , Dental Caries/therapy , Periodontal Diseases/therapy , Low-Level Light Therapy/methods , Lasers
6.
Biosens Bioelectron ; 258: 116327, 2024 Aug 15.
Article En | MEDLINE | ID: mdl-38703496

Proper customization in size and shape is essential in implantable bioelectronics for stable bio-signal recording. Over the past decades, many researchers have heavily relied on conventional photolithography processes to fabricate implantable bioelectronics. Therefore, they could not avoid the critical limitation of high cost and complex processing steps to optimize bioelectronic devices for target organs with various sizes and shapes. Here, we propose rapid prototyping using all laser processes to fabricate customized bioelectronics. PEDOT:PSS is selectively irradiated by an ultraviolet (UV) pulse laser to form wet-stable conductive hydrogels that can softly interact with biological tissues (50 µm line width). The encapsulation layer is selectively patterned using the same laser source by UV-curing polymer networks (110 µm line width). For high stretchability (over 100%), mesh structures are made by the selective laser cutting process. Our rapid prototyping strategy minimizes the use of high-cost equipment, using only a single UV laser source to process the electrodes, encapsulation, and substrates that constitute bioelectronics without a photomask, enabling the prototyping stretchable microelectrode array with an area of 1 cm2 less than 10 min. We fabricated an optimized stretchable microelectrode array with low impedances (∼1.1 kΩ at 1 kHz) that can effectively record rat's cardiac signals with various health states.


Biosensing Techniques , Electric Conductivity , Hydrogels , Lasers , Hydrogels/chemistry , Animals , Biosensing Techniques/instrumentation , Rats , Polymers/chemistry , Equipment Design , Polystyrenes/chemistry , Thiophenes
7.
Sci Adv ; 10(19): eadl1586, 2024 May 10.
Article En | MEDLINE | ID: mdl-38718128

Viscoelastic transformation of tissue drives aberrant cellular functions and is an early biomarker of disease pathogenesis. Tissues scale a range of viscoelastic moduli, from biofluids to bone. Moreover, viscoelastic behavior is governed by the frequency at which tissue is probed, yielding distinct viscous and elastic responses modulated over a wide frequency band. Existing tools do not quantify wideband viscoelastic spectra in tissues, leaving a vast knowledge gap. We present wideband laser speckle rheological microscopy (WB-SHEAR) that reveals elastic and viscous response over sub-megahertz frequencies previously not investigated in tissue. WB-SHEAR uses an optical, noncontact approach to quantify wideband viscoelastic spectra in specimens spanning a range of moduli from low-viscosity fibrin to highly elastic bone. Via laser scanning, micromechanical imaging is enabled to access wideband viscoelastic spectra in heterogeneous tumor specimens with high spatial resolution (25 micrometers). The ability to interrogate the viscoelastic landscape of diverse biospecimens could transform our understanding of mechanobiological processes in various diseases.


Elasticity , Rheology , Viscosity , Rheology/methods , Humans , Animals , Lasers , Microscopy/methods
8.
Sci Rep ; 14(1): 11173, 2024 05 15.
Article En | MEDLINE | ID: mdl-38750179

Laser weeding may contribute to less dependency on herbicides and soil tillage. Several research and commercial projects are underway to develop robots equipped with lasers to control weeds. Artificial intelligence can be used to locate and identify weed plants, and mirrors can be used to direct a laser beam towards the target to kill it with heat. Unlike chemical and mechanical weed control, laser weeding only exposes a tiny part of the field for treatment. Laser weeding leaves behind only ashes from the burned plants and does not disturb the soil. Therefore, it is an eco-friendly method to control weed seedlings. However, perennial weeds regrow from the belowground parts after the laser destroys the aerial shoots. Depletion of the belowground parts for resources might be possible if the laser continuously kills new shoots, but it may require many laser treatments. We studied how laser could be used to destroy the widespread and aggressive perennial weed Elymus repens after the rhizomes were cut into fragments. Plants were killed with even small dosages of laser energy and stopped regrowing. Generally, the highest efficacy was achieved when the plants from small rhizomes were treated at the 3-leaf stage.


Lasers , Weed Control , Weed Control/methods , Elymus/growth & development , Plant Weeds/growth & development , Plant Leaves/growth & development , Plant Leaves/radiation effects
9.
J Biomed Mater Res B Appl Biomater ; 112(6): e35432, 2024 Jun.
Article En | MEDLINE | ID: mdl-38817034

To investigate how patterns generated by femtosecond (fs) laser and femtosecond laser power affect the surface roughness (Ra) and biaxial flexural strength (BFS) of monolithic zirconia. Eighty disk-shaped zirconia specimens were divided into eight subgroups (n = 10): Control (C), airborne-particle abrasion (APA), 400 mW fs laser (spiral [SP(400)], square [SQ(400)], circular [CI(400)]), and 700 mW fs laser ([SP(700)], [SQ(700)], [CI(700)]). Ra values were calculated by using a surface profilometer. One additional specimen per group was analyzed with scanning electron microscopy and x-ray diffractometry. BFS values were obtained by using the piston-on-3-ball test. One-way ANOVA and either Tukey's HSD (BFS) or Tamhane's T2 (Ra) tests were used to evaluate data (α = 0.05). Regardless of the pattern and power, fs laser groups had higher Ra than C and APA, while SP groups had lower Ra than CI and SQ groups (p ≤ 0.004). For each pattern, Ra increased with higher laser power (p < 0.001), while the laser power did not affect the BFS (p ≥ 0.793). CI and SQ groups had lower BFS than the other groups (p ≤ 0.040), whereas SP groups had similar BFS to C and APA (p ≥ 0.430). Fs laser microstructuring with spiral surface pattern increased the Ra without jeopardizing the BFS of zirconia. Thus, this treatment might be an option to roughen tested zirconia.


Lasers , Materials Testing , Surface Properties , Zirconium , Zirconium/chemistry , Flexural Strength , Microscopy, Electron, Scanning
10.
Anal Chim Acta ; 1310: 342663, 2024 Jun 29.
Article En | MEDLINE | ID: mdl-38811130

The diagnosis of malignant melanoma, often an inconspicuous but highly aggressive tumor, is most commonly done by histological examination, while additional diagnostic methods on the level of elements and molecules are constantly being developed. Several studies confirmed differences in the chemical composition of healthy and tumor tissue. Our study presents the potential of the LIBS (Laser-Induced-Breakdown Spectroscopy) technique as a diagnostic tool in malignant melanoma (MM) based on the quantitative changes in elemental composition in cancerous tissue. Our patient group included 17 samples of various types of malignant melanoma and one sample of healthy skin tissue as a control. To achieve a clear perception of results, we have selected two biogenic elements (calcium and magnesium), which showed a dissimilar distribution in cancerous tissue from its healthy surroundings. Moreover, we observed indications of different concentrations of these elements in different subtypes of malignant melanoma, a hypothesis that requires confirmation in a more extensive sample set. The information provided by the LIBS Imaging method could potentially be helpful not only in the diagnostics of tumor tissue but also be beneficial in broadening the knowledge about the tumor itself.


Lasers , Magnesium , Melanoma , Skin Neoplasms , Spectrum Analysis , Humans , Melanoma/pathology , Melanoma/diagnostic imaging , Melanoma/diagnosis , Melanoma/chemistry , Spectrum Analysis/methods , Magnesium/analysis , Skin Neoplasms/pathology , Skin Neoplasms/diagnostic imaging , Calcium/analysis
11.
Lasers Med Sci ; 39(1): 144, 2024 May 29.
Article En | MEDLINE | ID: mdl-38809462

Enterococcus faecalis is among the most resistant bacteria found in infected root canals. The demand for cutting-edge disinfection methods has rekindled research on photoinactivation with visible light. This study investigated the bactericidal activity of femtosecond laser irradiation against vancomycin-resistant Enterococcus faecalis V583 (VRE). The effect of parameters such as wavelength and energy density on the viability and growth kinetics of VRE was studied to design an optimized laser-based antimicrobial photoinactivation approach without any prior addition of exogenous photosensitizers. The most effective wavelengths were 430 nm and 435 nm at a fluence of 1000 J/cm2, causing a nearly 2-log reduction (98.6% and 98.3% inhibition, respectively) in viable bacterial counts. The colony-forming units and growth rate of the laser-treated cultures were progressively decreased as energy density or light dose increased at 445 nm but reached a limit at 1250 J/cm2. At a higher fluence of 2000 J/cm2, the efficacy was reduced due to a photobleaching phenomenon. Our results highlight the importance of optimizing laser exposure parameters, such as wavelength and fluence, in bacterial photoinactivation experiments. To our knowledge, this is the first study to report an optimized wavelength for the inactivation of VRE using visible femtosecond laser light.


Enterococcus faecalis , Enterococcus faecalis/radiation effects , Enterococcus faecalis/growth & development , Enterococcus faecalis/drug effects , Humans , Vancomycin-Resistant Enterococci/radiation effects , Vancomycin-Resistant Enterococci/growth & development , Vancomycin-Resistant Enterococci/drug effects , Microbial Viability/radiation effects , Lasers , Kinetics , Vancomycin Resistance
12.
BMC Med Educ ; 24(1): 583, 2024 May 28.
Article En | MEDLINE | ID: mdl-38807167

BACKGROUND: This study aimed to design and implement a gamified application about the theoretical aspects of laser applications in dentistry and investigate students' satisfaction with their learning experience. METHODS: An engaging educational program named Essential Skills and Knowledge in Learning Laser (ESKILLD) was developed to teach laser applications in dentistry. The program comprises two primary components: a "Tutorial and Quiz" section and a "Games" section. Final-year dental students were tasked with installing and using this application. A 29-item validated questionnaire (Cronbach's alpha = 0.97, ICC = 0.94) was used to evaluate students' perceptions of the applications' design and functionality. The influence of participants' gender and Grade Point Average (GPA) on their satisfaction levels was examined via the student t-test and Pearson's correlation, with a significance level of 0.05. RESULTS: The study had 56 participants, of which 37 were female (66.07%), and 19 were male (33.92%). The students' average GPA was 15.16 out of 20. The mean rating for ESKILLD's design and functionality was 1.39 ± 0.47 and 1.37 ± 0.46, respectively, signifying a high satisfaction level. Female students rated the application's coherence and learning perception significantly higher than their male counterparts (p < 0.05). However, gender did not significantly influence scores on other perception aspects or overall scores. Students' GPAs and their perception scores did not have a significant correlation. CONCLUSIONS: The results indicate that the participants were generally satisfied with the game's features and attitudes towards it, which underscores the potential effectiveness of gamification in dental courses focused on laser applications.


Education, Dental , Personal Satisfaction , Students, Dental , Humans , Students, Dental/psychology , Female , Male , Education, Dental/methods , Lasers , Educational Measurement , Video Games , Surveys and Questionnaires , Young Adult
13.
J Biomed Opt ; 29(6): 065002, 2024 Jun.
Article En | MEDLINE | ID: mdl-38812963

Significance: Preparation of a recipient cytoplast by oocyte enucleation is an essential task for animal cloning and assisted reproductive technologies in humans. The femtosecond laser is a precise and low-invasive tool for oocyte enucleation, and it should be an appropriate alternative to traditional enucleation by a microneedle aspiration. However, until recently, the laser enucleation was performed only with applying a fluorescent dye. Aim: This work is aimed to (1) achieve femtosecond laser oocyte enucleation without applying a fluorescent dye and (2) to study the effect of laser destruction of chromosomes on the structure and dynamics of the spindle. Approach: We applied polarized light microscopy for spindle visualization and performed stain-free mouse and human oocyte enucleation with a 1033 nm femtosecond laser. Also, we studied transformation of a spindle after metaphase plate elimination by a confocal microscopy. Results: We demonstrated a fundamental possibility of inactivating the metaphase plate in mouse and human oocytes by 1033 nm femtosecond laser radiation without applying a fluorescent dye. Irradiation of the spindle area, visualized by polarized light microscopy, resulted in partly or complete metaphase plate destruction but avoided the microtubules impairment. After the metaphase plate elimination, the spindle reorganized, however, it was not a complete depolymerization. Conclusions: This method of recipient cytoplast preparation is expected to be useful for animal cloning and assisted reproductive technologies.


Oocytes , Animals , Mice , Oocytes/cytology , Humans , Female , Lasers , Spindle Apparatus , Microscopy, Confocal/methods , Metaphase , Microscopy, Polarization/methods
14.
Biomed Phys Eng Express ; 10(4)2024 May 21.
Article En | MEDLINE | ID: mdl-38718764

Evaluation of skin recovery is an important step in the treatment of burns. However, conventional methods only observe the surface of the skin and cannot quantify the injury volume. Optical coherence tomography (OCT) is a non-invasive, non-contact, real-time technique. Swept source OCT uses near infrared light and analyzes the intensity of light echo at different depths to generate images from optical interference signals. To quantify the dynamic recovery of skin burns over time, laser induced skin burns in mice were evaluated using deep learning of Swept source OCT images. A laser-induced mouse skin thermal injury model was established in thirty Kunming mice, and OCT images of normal and burned areas of mouse skin were acquired at day 0, day 1, day 3, day 7, and day 14 after laser irradiation. This resulted in 7000 normal and 1400 burn B-scan images which were divided into training, validation, and test sets at 8:1.5:0.5 ratio for the normal data and 8:1:1 for the burn data. Normal images were manually annotated, and the deep learning U-Net model (verified with PSPNe and HRNet models) was used to segment the skin into three layers: the dermal epidermal layer, subcutaneous fat layer, and muscle layer. For the burn images, the models were trained to segment just the damaged area. Three-dimensional reconstruction technology was then used to reconstruct the damaged tissue and calculate the damaged tissue volume. The average IoU value and f-score of the normal tissue layer U-Net segmentation model were 0.876 and 0.934 respectively. The IoU value of the burn area segmentation model reached 0.907 and f-score value reached 0.951. Compared with manual labeling, the U-Net model was faster with higher accuracy for skin stratification. OCT and U-Net segmentation can provide rapid and accurate analysis of tissue changes and clinical guidance in the treatment of burns.


Burns , Deep Learning , Image Processing, Computer-Assisted , Lasers , Skin , Tomography, Optical Coherence , Tomography, Optical Coherence/methods , Animals , Burns/diagnostic imaging , Mice , Skin/diagnostic imaging , Image Processing, Computer-Assisted/methods , Algorithms
15.
J Pharm Biomed Anal ; 245: 116184, 2024 Aug 01.
Article En | MEDLINE | ID: mdl-38692214

The plant of Paeonia lactiflora Pall. belongs to Ranunculaceae, and its root can be divided into two categories according to different processing methods, which included that one was directly dried without peeling the root of the P. lactiflora (PR), and the other was peeled the root of the P. lactiflora (PPR) after boiled and dried. To evaluate the difference of chemical components, UPLC-ESI-Q-Exactive Focus-MS/MS and UPLC-QQQ-MS were applied. The distribution of chemical components in different tissues was located by laser microdissection (LMD), especially the different ingredients. A total of 86 compounds were identified from PR and PPR. Four kind of tissues were isolated from the fresh root of the P. lactiflora (FPR), and 54 compounds were identified. Especially the content of gallic acid, albiflorin, and paeoniflorin with high biological activities were the highest in the cork, but they were lower in PR than that in PPR, which probably related to the process. To illustrate the difference in pharmacological effects of PR and PPR, the tonifying blood and analgesic effects on mice were investigated, and it was found that the tonifying blood and analgesic effects of PPR was superior to that of PR, even though PR had more constituents. The material basis for tonifying blood and analgesic effect of the root of P. lactiflora is likely to be associated with an increase in constituents such as paeoniflorin and paeoniflorin lactone after boiled and peeled. The study was likely to provide some theoretical support for the standard and clinical application.


Glucosides , Monoterpenes , Paeonia , Plant Roots , Tandem Mass Spectrometry , Paeonia/chemistry , Plant Roots/chemistry , Animals , Mice , Tandem Mass Spectrometry/methods , Chromatography, High Pressure Liquid/methods , Glucosides/analysis , Glucosides/chemistry , Male , Monoterpenes/pharmacology , Monoterpenes/analysis , Monoterpenes/chemistry , Microdissection/methods , Gallic Acid/analysis , Gallic Acid/chemistry , Plant Extracts/chemistry , Plant Extracts/pharmacology , Lasers , Analgesics/pharmacology , Analgesics/chemistry , Analgesics/analysis , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Spectrometry, Mass, Electrospray Ionization/methods , Liquid Chromatography-Mass Spectrometry , Bridged-Ring Compounds
16.
Biosens Bioelectron ; 259: 116386, 2024 Sep 01.
Article En | MEDLINE | ID: mdl-38749285

Faced with the increasing prevalence of chronic kidney disease (CKD), portable monitoring of CKD-related biomarkers such as potassium ion (K+), creatinine (Cre), and lactic acid (Lac) levels in sweat has shown tremendous potential for early diagnosis. However, a rapidly manufacturable portable device integrating multiple CKD-related biomarker sensors for ease of sweat testing use has yet to be reported. Here, a portable electrochemical sensor integrated with multifunctional laser-induced graphene (LIG) circuits and laser-printed nanomaterials based working electrodes fabricated by fully automatic laser manufacturing is proposed for non-invasive human kidney function monitoring. The sensor comprises a two-electrode LIG circuit for K+ sensing, a three-electrode LIG circuit with a Kelvin compensating connection for Cre and Lac sensing, and a printed circuit board based portable electrochemical workstation. The working electrodes containing Cu and Cu2O nanoparticles fabricated by two-step laser printing show good sensitivity and selectivity toward Cre and Lac sensing. The sensor circuits are fabricated by generating a hydrophilic-hydrophobic interface on a patterned LIG through laser. This sensor recruited rapid laser manufacturing and integrated with multifunctional LIG circuits and laser-printed nanomaterials based working electrodes, which is a potential kidney function monitoring solution for healthy people and kidney disease patients.


Biosensing Techniques , Graphite , Lasers , Nanostructures , Renal Insufficiency, Chronic , Humans , Graphite/chemistry , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Nanostructures/chemistry , Renal Insufficiency, Chronic/diagnosis , Kidney/chemistry , Creatinine/analysis , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Sweat/chemistry , Equipment Design , Lactic Acid/analysis , Electrodes , Kidney Function Tests/instrumentation , Biomarkers/analysis , Copper/chemistry
17.
Biomaterials ; 309: 122620, 2024 Sep.
Article En | MEDLINE | ID: mdl-38788456

Photodynamic therapy (PDT) is a promising modality for cancer treatment. However, limited tissue penetration of external radiation and complicated tumor microenvironments (TMEs) restrict the antitumor efficiency of PDT. Herein, we report an energy-storing DNA-based hydrogel, which enables tumor-selective PDT without external radiation and regulates TMEs to achieve boosted PDT-mediated tumor immunotherapy. The system is constructed with two ultralong single-stranded DNA chains, which programmed partial complementary sequences and repeated G-quadruplex forming AS1411 aptamer for photosensitizer loading via hydrophobic interactions and π-π stacking. Then, energy-storing persistent luminescent nanoparticles are incorporated to sensitize PDT selectively at tumor site without external irradiation, generating tumor antigen to agitate antitumor immune response. The system catalytically generates O2 to alleviate hypoxia and releases inhibitors to reverse the IDO-related immunosuppression, synergistically remodeling the TMEs. In the mouse model of breast cancer, this hydrogel shows a remarkable tumor suppression rate of 78.3 %. Our study represents a new paradigm of photodynamic immunotherapy against cancer by combining laser-free fashion and TMEs remodeling.


DNA , Hydrogels , Immunotherapy , Photochemotherapy , Photosensitizing Agents , Tumor Microenvironment , Animals , Photochemotherapy/methods , Tumor Microenvironment/drug effects , Hydrogels/chemistry , Immunotherapy/methods , Female , Mice , Photosensitizing Agents/pharmacology , Photosensitizing Agents/chemistry , Photosensitizing Agents/therapeutic use , Mice, Inbred BALB C , Humans , Cell Line, Tumor , Lasers
18.
Biomater Adv ; 161: 213882, 2024 Jul.
Article En | MEDLINE | ID: mdl-38710121

Metallic lattice scaffolds are designed to mimic the architecture and mechanical properties of bone tissue and their surface compatibility is of primary importance. This study presents a novel surface modification protocol for metallic lattice scaffolds printed from a superelastic Ti-Zr-Nb alloy. This protocol consists of dynamic chemical etching (DCE) followed by silver nanoparticles (AgNP) decoration. DCE, using an 1HF + 3HNO3 + 12H2O23% based solution, was used to remove partially-fused particles from the surfaces of different as-built lattice structures (rhombic dodecahedron, sheet gyroid, and Voronoi polyhedra). Subsequently, an antibacterial coating was synthesized on the surface of the scaffolds by a controlled (20 min at a fixed volume flowrate of 500 mL/min) pumping of the functionalization solutions (NaBH4 (2 mg/mL) and AgNO3 (1 mg/mL)) through the porous structures. Following these treatments, the scaffolds' surfaces were found to be densely populated with Ag nanoparticles and their agglomerates, and manifested an excellent antibacterial effect (Ag ion release rate of 4-8 ppm) suppressing the growth of both E. coli and B. subtilis bacteria up to 99 %. The scaffold extracts showed no cytotoxicity and did not affect cell proliferation, indicating their safety for subsequent use as implants. A cytocompatibility assessment using MG-63 spheroids demonstrated good attachment, spreading, and active migration of cells on the scaffold surface (over 96 % of living cells), confirming their biotolerance. These findings suggest the promise of this surface modification approach for developing superelastic Ti-Zr-Nb scaffolds with superior antibacterial properties and biocompatibility, making them highly suitable for bone implant applications.


Anti-Bacterial Agents , Metal Nanoparticles , Silver , Surface Properties , Tissue Scaffolds , Titanium , Zirconium , Silver/chemistry , Silver/pharmacology , Metal Nanoparticles/chemistry , Titanium/chemistry , Titanium/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Tissue Scaffolds/chemistry , Zirconium/chemistry , Zirconium/pharmacology , Humans , Niobium/chemistry , Niobium/pharmacology , Lasers , Escherichia coli/drug effects , Alloys/chemistry , Alloys/pharmacology , Bacillus subtilis/drug effects , Powders , Materials Testing , Cell Proliferation/drug effects
19.
Lasers Med Sci ; 39(1): 137, 2024 May 25.
Article En | MEDLINE | ID: mdl-38795227

This paper introduces a novel application of the laser speckle technique in dentistry, focusing on assessing the efficiency of dental excavation methods used to remove decayed tooth structure. The aim is to evaluate the efficiency of two chemo-mechanical agents and the high-speed drill using the laser speckle technique, which offers objective, non-invasive, and real-time evaluation capabilities. Extracted human primary molars with active occlusal carious lesions were sectioned into three parts, with each part allocated to one of three groups: Group 1 (Brix3000®), Group 2 (Papacarie DUO®), and Group 3 (High-speed drill mechanical caries removal). Caries removal was performed using the designated agent or method for each group. After caries excavation, speckle imaging using a 632.8 nm laser was conducted. Additionally, SEM was used to acquire micro-photographs of the surface morphology of the treated samples. The findings reveal insights into the comparative efficiency of the three dental excavation agents and methods using the laser speckle technique. The speckle parameters extracted from speckle patterns generated by treated teeth provide valuable information for evaluating the performance of the excavation methods. The scanning electron microscopy images also offer detailed visual evidence to support the analysis. This paper demonstrates the potential of the laser speckle technique for assessing the efficiency of dental excavation methods. The objective, non-invasive, and real-time evaluation provided offers advantages over subjective visual assessment and manual measurements.


Dental Caries , Dental Cavity Preparation , Lasers , Humans , Dental Caries/therapy , Dental Caries/diagnostic imaging , Dental Cavity Preparation/methods , Dental Cavity Preparation/instrumentation , Molar/diagnostic imaging , Microscopy, Electron, Scanning , Tooth, Deciduous/diagnostic imaging
20.
Talanta ; 275: 126194, 2024 Aug 01.
Article En | MEDLINE | ID: mdl-38703481

Lung cancer staging is crucial for personalized treatment and improved prognosis. We propose a novel bimodal diagnostic approach that integrates LIBS and Raman technologies into a single platform, enabling comprehensive tissue elemental and molecular analysis. This strategy identifies critical staging elements and molecular marker signatures of lung tumors. LIBS detects concentration patterns of elemental lines including Mg (I), Mg (II), Ca (I), Ca (II), Fe (I), and Cu (II). Concurrently, Raman spectroscopy identifies changes in molecular content, such as phenylalanine (1033 cm-1), tyrosine (1174 cm-1), tryptophan (1207 cm-1), amide III (1267 cm-1), and proteins (1126 cm-1 and 1447 cm-1), among others. The bimodal information is fused using a decision-level Bayesian fusion model, significantly enhancing the performance of the convolutional neural network architecture in classification algorithms, with an accuracy of 99.17 %, sensitivity of 99.17 %, and specificity of 99.88 %. This study provides a powerful new tool for the accurate staging and diagnosis of lung tumors.


Lung Neoplasms , Spectrum Analysis, Raman , Spectrum Analysis, Raman/methods , Lung Neoplasms/diagnosis , Lung Neoplasms/pathology , Humans , Lasers , Bayes Theorem , Neoplasm Staging , Neural Networks, Computer
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