- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2018
- electromagnetic pulse
- cell proliferation
- cell membrane permeability
- cell response to electromagnetic stress
- apoptosis
- cancer therapy
- necrosis
- Intelligent Medical Engineering
- V.N. Karazin Kharkiv National University
-
Macular microvasculature features before and after vitrectomy in idiopathic macular epiretinal membrane: an OCT angiography analysis
摘要： Purpose To evaluate pre-operative and post-operative morphologic characteristics in idiopathic macular epiretinal membrane (ERM) by optical coherence tomography angiography (OCTA). Methods Thirty-three subjects with unilateral idiopathic ERM were enrolled and the contralateral eyes served as controls. Vascular parameters including super?cial capillary plexus (SCP), deep capillary plexus (DCP), outer capillary plexus (OCP), and choroidal capillary plexus (CCP) were evaluated by OCTA. Results The super?cial foveal avascular zone (FAZ) was signi?cantly smaller in eyes with ERM (P < 0.0001). The vessel densities (VDs) were signi?cantly increased in the fovea but dramatically decreased in the parafovea in SCP and DCP of ERM eyes (all P < 0.0001), in contrast to those in OCP and CCP. The blood ?ow was augmented in OCP but declined in choroid compared with the controls. In CCP, the mean foveal VD in ERM was signi?cantly smaller (P = 0.023), whereas parafoveal VD did not signi?cantly change (P = 0.66). At 6 months after surgery, ?ow area was decreased in OCP (P = 0.0007), and foveal and parafoveal VDs were signi?cantly altered in all layers except the foveal VD in OCP and the choroid (all P < 0.05). The total and inner retinal thickness of the fovea and parafovea were correlated with pre-operative and post-operative visual outcomes, respectively. Smaller FAZ and greater interocular differences between post-operative and fellow eyes in FAZ were associated with worse post-operative visual outcomes. Conclusions OCTA provides a better display of the vascular network of the retina and choroid to evaluate the severity and surgical prognosis of ERM patients.
关键词： Microvasculature,Vitrectomy,Epiretinal membrane,Optical coherence tomography angiography
更新于2025-09-10 09:29:36
-
Camouflaged Nanosilver with Excitation Wavelength Dependent High Quantum Yield for Targeted Theranostic
摘要： The present study shows the thorough investigations on optical properties and hydrodynamic diameters of glutathione (GSH) stabilized nanosilver clusters (AgNC) at different stages of synthesis and engineering for the optimized absolute quantum yield to generate fluorescent images of Dalton Lymphoma Ascites (DLA) tumour bearing mice. The initial increment of quantum yield was wavelength dependent and finally it became 0.509 which was due to the camouflaging or entrapment of AgNC in macrophages membranes. The potentiality of macrophages membrane camouflaged silver nanoclusters (AgM) was reflected in the cell viability assay and confocal based live dead cell assay where the AgM has better cell killing effect compared to AgNC with reduced dosage and in vivo mice imaging generated the clear visualization at the tumour sites. Therefore, from the present study, it can be considered that the camouflaged nanosilver can be used for targeted theranostic applications.
关键词： nanosilver clusters,macrophage membrane,theranostic,fluorescence imaging,quantum yield
更新于2025-09-10 09:29:36
-
[IEEE 2018 14th International Conference on Advanced Trends in Radioelecrtronics, Telecommunications and Computer Engineering (TCSET) - Lviv-Slavske (2018.2.20-2018.2.24)] 2018 14th International Conference on Advanced Trends in Radioelecrtronics, Telecommunications and Computer Engineering (TCSET) - Special features of structural design for a fiber-optic microdisplacement transducer
摘要： In this paper, we describe the design of a fiber-optic pressure sensor and the principle of operation. The principle of operation of fiber-optic pressure sensors is as follows. From the radiation source, the light flux along the supply optical fibers is directed to the side of the membrane at an angle, the value of which is selected from the condition of ensuring the maximum sensitivity of the conversion and the depth of modulation of the optical signal. Under the influence of controlled pressure, the membrane deflects, and in the central part the gap between the membrane and the bevelled ends of the optical fibers will be less than the initial value X0. As a result, the reflectivity for electromagnetic waves in the region of the chamfered ends of the optical fibers changes, and accordingly the intensity of the light flux reflected at an angle from the given region, which carries information about the measured pressure and arrives along the diverting optical fibers to the radiation receiver, changes. The optical system of a fiber-optic pressure sensor is calculated, which consists in determining a number of fiber-optic micro-displacement design parameters the MathCAD transducer. Mathematical modeling environment was carried out. Based on the results of mathematical modeling, a new design solution has been proposed for a fiber-optic micro-displacement transducer, in which the incoming and outgoing optical fibers are cut off and located at a calculated angle. The function of converting a fiber-optic micro-displacement transducer is defined. The selected parameters ensure the fulfillment of the conditions for reducing the temperature and dynamic errors, increasing the sensitivity of the optical signal conversion while reducing the mass-dimensional characteristics of the fiber-optic pressure sensor.
关键词： silicon membrane,transformation function,optical fiber,fiber-optic sensor,fiber-optic transducer
更新于2025-09-10 09:29:36
-
[Advances in Experimental Medicine and Biology] Glycobiophysics Volume 1104 || Unraveling of Lipid Raft Organization in Cell Plasma Membranes by Single-Molecule Imaging of Ganglioside Probes
摘要： Gangliosides are involved in a variety of physiological roles and particularly in the formation and function of lipid rafts in cell membranes. However, the dynamic behaviors of gangliosides have not been investigated in living cells owing to the lack of fluorescent probes that behave like their parental molecules. This has recently been resolved by developing new fluorescent ganglioside analogues that act similarly to their parental molecules, synthesized by only chemical methods. We performed single fluorescent-molecule imaging and revealed that ganglioside probes dynamically enter and exit rafts containing CD59, a glycosylphosphatidylinositol (GPI)-anchored protein, both before and after stimulation. The residency time of our ganglioside probes in CD59 oligomers was 48 ms after stimulation. The residency times in CD59 homodimer and monomer rafts were 40 and 12 ms, respectively. These results reveal the first direct evidence that GPI-anchored receptors and gangliosides interact in a cholesterol-dependent manner. Furthermore, they demonstrate that gangliosides continually move in and out of rafts that contain CD59 in an extremely dynamic manner and at a much higher frequency than expected. In this chapter, we review methods for the development and single-molecule imaging of new fluorescent ganglioside analogues and discuss how raft domains are formed, both before and after receptor engagement.
关键词： GPI-anchored protein,Single-molecule fluorescence tracking,Cell plasma membrane,Raft domains,Fluorescent ganglioside probes
更新于2025-09-10 09:29:36
-
An Improved Design and Versatile New Lamination Fabrication Method for Twin Electrode Thin Layer Cells Utilizing Track-Etch Membranes
摘要： Reported here are laminated membrane electrodes, an improved design and more advantageous method of fabrication for previously reported thin layer cell electrode systems developed on track-etch membranes. The laminated membrane approach potentially further improves flow resistance by dramatically reducing the surface area to volume ratio, but also produces a cohesive device that can be more readily applied to a broad range of applications. In addition, this new fabrication method was implemented in a scalable, commercial process and resulting product demonstrations indicate that volume manufacturing is feasible. Characterization of laminated membrane electrodes reveal redox cycling amplification factors as high as 30 with linear responses to variable concentrations of redox couple. These performance characteristics are shown to be comparable to similar generator-collector systems fabricated through much more laborious laboratory methods. This combination of added versatility, cost-reduced fabrication and exceptional performance clearly reveals unrealized potential of track-etch membrane approaches and boosts their candidacy as powerful new options for generator-collector electrode systems.
关键词： membrane,thin layer cell,redox cycling,generator-collector electrodes,microfabrication
更新于2025-09-10 09:29:36
-
Copper-surrogated galvanic displacement of silver dendrite imprinted on flexible and transparent silk fibroin membrane as a SERS-active substrate and sub-dividable catalyst
摘要： By employing copper grid as a surrogate agent, we present a facial, reagent-free and cost-e?ective approach to imprint the exquisite silver dendroid nanostructures on ?exible silk ?broin membrane, which double roles as both optical enhancers and catalytic-active sites over many chemical reactions. Unlike the conventional rigid substrates, this hybrid Ag/protein composite exhibits many previous-inaccessible properties of ?exibility, transparency, biocompatibility, molecular permeability and optical manipulation. The galvanic displacement was facilitated by a high pressure uv-lamp illumination (365 nm), shortening the dendroid growth time to be within a few minutes. The resulting substrate was characterized by microscopic image, revealing a decent 3D Ag dendrite architecture and interpenetrated crystal network, which arguably enlarged the entire surface area and keenly regulated the optical/electric property of ?brillated protein ?lm. The underlying principle of copper-initiated silver reduction and growth of crystal structure was discoursed and veri?ed with in-situ spectroscopic interrogation. Moreover, our comprehensive study supports that sub-dividable substrate enables to perform catalytic reaction under a wide range of conditions. This exploration renders a thrust to expand biopolymeric membrane into a wide breadth of applications of bendable devices through chemical modi?cations, exhaustively and economically.
关键词： Galvanic replacement,Surface-enhanced Raman scattering,Sub-dividable catalyst,Silk membrane,Plasmon-driven photo-reduction
更新于2025-09-10 09:29:36
-
A facile synthesis of graphene nanoribbon-quantum dot hybrids and their application for composite electrolyte membrane in direct methanol fuel cells
摘要： In this work, we report the concept of synthesizing graphene nanoribbon-graphene quantum dot (GNR-GQD) hybrids with even grafting of GQD on GNR sheet in a facile single step process under ultrasonication in chlorosulfonic acid. Further, diazotization route is followed for the preparation of 4-benzenediazonium sulfonate precursor to sulfonate both GNR and GQD to form sulfonated graphene nanoribbons-sulfonated graphene quantum dots (sGNR-sGQD) nanohybrids. Synergistic and structure dependent effect of nanohybrids is seen via its dispersion in sulfonated poly(ether ether ketone) (sPEEK) to form nanocomposite membrane. sPEEK/sGNR-sGQD (1.5 wt. %) nanocomposite membrane shows remarkable direct methanol fuel cell (DMFC) performance compared to pristine sPEEK and Nafion 117 with 40 % increment in peak power density along with higher durability up to 100 h due to better physicochemical properties like water uptake, ion exchange capacity, proton conductivity, and reduced methanol crossover to suggest its potential which includes diverse membrane applications.
关键词： Graphene nanoribbon-graphene quantum dot hybrids,Nanohybrids,Nanocomposite membrane,Sulfonated poly(ether ether ketone),Direct methanol fuel cell
更新于2025-09-10 09:29:36
-
Spectral-Domain Optical Coherence Tomography Findings in Neurofibromatosis Type 2
摘要： Neurofibromatosis type 2 (NF2) is an autosomal-dominant disease, characterized by bilateral vestibular schwannomas, multiple central nervous system (CNS) tumors, skin tumors, and juvenile cataract. The present study assessed retinal abnormalities using spectral-domain optical coherence tomography (SD-OCT) in a case series of NF2 patients. METHODS. Nine NF2 patients from the neurofibromatosis outpatient reference center of the Federal University of Minas Gerais, in Brazil, were submitted to a complete anamnesis and a detailed ophthalmic evaluation, including SD-OCT, to detect retinal lesions. RESULTS. Of the nine NF2 patients evaluated, five had an early onset (<20 years) of NF2, and four patients had a late onset (>20 years) of symptoms. SD-OCT scans revealed retinal abnormalities in every patient with early onset (EOS) and in two patients with late onset (LOS) of the disease. In the EOS group, SD-OCT scans revealed flame-shaped epiretinal membranes (ERM) with peculiar characteristics in four eyes of three patients. Two patients had fine undulations of the inner retinal surface with a subtle ERM. Retinal hamartomas were present in four eyes of three patients with EOS; in two eyes, they were subclinical and were detected only by SD-OCT scans. In two patients with LOS and one patient with EOS, SD-OCT scans revealed retinal tufts of a nerve fiber layer. CONCLUSIONS. SD-OCT revealed ERM in most patients with NF2, therefore it may be a valuable exam for evaluating NF2 patients. Epiretinal membranes in NF2 has unique features, distinguishing it from idiopathic ERM or membranes associated with other diseases. We suggest that flame-shaped ERM seems to be specific for NF2 and that ERM can be considered as an important diagnostic sign of NF2.
关键词： epiretinal membrane,neurofibromatosis type 2,vestibular schwannoma,optical coherence tomography,retina
更新于2025-09-10 09:29:36
-
In-Situ imaging detection of cell membrane and intracellular cholesterol via cascade reactions
摘要： Herein, an e?ective membrane-to-intracellular cholesterol detection strategy was designed based on cascade reactions. A biochip array was ?rstly fabricated by consecutively immobilizing luminol modi?ed gold nanoparticles (Au@luminol), soybean peroxidase (SBP) and cholesterol oxidase (ChoX) on the cellulose acetate (CA) membrane functionalized home-made micropore array. When cholesterol existed, it was oxidized by ChoX generating H2O2, which further triggered the CL reaction under the SBP catalysis, the CL signals were collected by a charge-coupled device (CCD). The proposed strategy exhibited a wide linear range from 0.12 μM to 1000 μM and relatively low detection limit (LOD) of 0.08 μM. Furthermore，it could be used to in-situ detect membrane cholesterol and intracelluar esteri?ed cholesterol in HepG2 cells. After activated HepG2 cells were added to the modi?ed biochip, membrane cholesterol was detected directly. Intracelluar esteri?ed cholesterol was detected through the introduction of triton X-100 and cholesteryl esterase (ChoE). Additionally, the cholesterol content in cells was changed after stimulated by drugs, such as apolipoprotein A-I (ApoA-I), pitavastatin or probucol. The correlation of the CL signal with the amount of cholesterol con?rmed that our strategy was feasible to simultaneously detect membrane and intracellular cholesterol at di?erent cellular states. The proposed strategy exhibited excellent sensitivity, selectivity, stability, and reproducibility in a simple, cheap way, which opened a new door for studying clinic treatment of the cholesterol-related diseases.
关键词： CL image,In-situ,Intracelluar cholesterol,Membrane cholesterol
更新于2025-09-10 09:29:36
-
Small-Angle Neutron Scattering Reveals Energy Landscape for Rhodopsin Photoactivation
摘要： Knowledge of the activation principles for G-protein-coupled receptors (GPCRs) is critical to development of new pharmaceuticals. Rhodopsin is the archetype for the largest GPCR family, yet the changes in protein dynamics that trigger signaling are not fully understood. Here we show that rhodopsin can be investigated by small-angle neutron scattering (SANS) in fully protiated detergent micelles under contrast matching to resolve light-induced changes in the protein structure. In SANS studies of membrane proteins, the zwitterionic detergent [(Cholamidopropyl)dimethylammonio]-propanesulfonate (CHAPS) is advantageous because of the low contrast difference between the hydrophobic core and hydrophilic head groups as compared to alkyl glycoside detergents. Combining SANS results with quasielastic neutron scattering (QENS) reveals how changes in volumetric protein shape are coupled (slaved) to the aqueous solvent. Upon light exposure rhodopsin is swollen by penetration of water into the protein core, allowing interactions with effector proteins in the visual signaling mechanism.
关键词： Detergent,Neutron Scattering,Hydration,GPCR,Protein Dynamics,Vision,Membrane Proteins,Energy landscape,Slaving,Rhodopsin
更新于2025-09-10 09:29:36