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Saudi Journal of Biological Sciences Aug 2021Asthma as chronic airway disease has high prevalence in children and imbalance of Th1/Th2 is a critical mechanism in pathogenesis of the asthma. Baicalein as a cell...
Asthma as chronic airway disease has high prevalence in children and imbalance of Th1/Th2 is a critical mechanism in pathogenesis of the asthma. Baicalein as a cell protective and anti-inflammatory flavonoid may have anti-asthma effect. Therefore, for better using lung, baicalein was used in chitosan-nanoparticle as anti-asthma treatment. Baicalein was loaded and encapsulated in chitosan nanoparticle. The morphology, physical characters (particle size, zeta potential and FT-IR) were analyzed. Drug encapsulation and loading capacity, accumulative release-time were studied. After asthma model producing, the mice were treated with L-B-NP and E-B-NP. At least, MCh challenge test, Cytokines measurement and Lung Histopathology were done. Nanoparticles had average size 285 ± 25 nm with negative charge -2.5 mV. The L-B-NP decreased penh value and E-B-NP decreased inflammation. Both nanoparticles increased IL-12 and decreased IL-5. Also, L-B-NP decreased mucus secretion in bronchi. L-B-NP and E-B-NP control immune-allergo-inflammatory response of asthma. L-B-NP controlled AHR and E-B-NP controlled inflammation that can be used as controlling anti-asthma drug.
PubMed: 34354413
DOI: 10.1016/j.sjbs.2021.04.009 -
Advanced Materials (Deerfield Beach,... Aug 2021The growing demand for ubiquitous data collection has driven the development of sensing technologies with local data processing. As a result, solution-processed...
The growing demand for ubiquitous data collection has driven the development of sensing technologies with local data processing. As a result, solution-processed semiconductors are widely employed due to their compatibility with low-cost additive manufacturing on a wide range of substrates. However, to fully realize their potential in sensing applications, high-performance scalable analog amplifiers must be realized. Here, ohmic-contact-gated transistors (OCGTs) based on solution-processed semiconducting single-walled carbon nanotubes are introduced to address this unmet need. This new device concept enables output current saturation in the short-channel limit without compromising output current drive. The resulting OCGTs are used in common-source amplifiers to achieve the highest width-normalized output current (≈30 µA µm ) and length-scaled signal gain (≈230 µm ) to date for solution-processed semiconductors. The utility of these amplifiers for emerging sensing technologies is demonstrated by the amplification of complex millivolt-scale analog biological signals including the outputs of electromyography, photoplethysmogram, and accelerometer sensors. Since the OCGT design is compatible with other solution-processed semiconducting materials, this work establishes a general route to high-performance, solution-processed analog electronics.
PubMed: 34270835
DOI: 10.1002/adma.202100994 -
The Journal of Emergency Medicine 1987Cardiac dysrhythmias are easy. Unlike the lung (which has formidable neuroendocrine, metabolic, and respiratory responsibilities), the heart is simple. It is an... (Review)
Review
Cardiac dysrhythmias are easy. Unlike the lung (which has formidable neuroendocrine, metabolic, and respiratory responsibilities), the heart is simple. It is an innervated muscular pump. A resting Purkinje or ventricular muscle cell membrane maintains a charge of about 90 millivolts. The five phases of a cardiac action potential are similar to the action potential in skeletal muscle, however, the cardiac action potential lasts a hundred times longer. When sodium specific "fast" channels and calcium specific "slow" channels open, positive ions rush into the myocardial cell, thus causing rapid membrane depolarization. In order to produce an action potential, some stimulus must decrease the membrane potential from -90 millivolts to "threshold" or -60 millivolts. Purkinje fibers do not have a stable phase for diastolic potential. These fibers continuously depolarize during diastole. Hypoxemia or hypokalemia may exacerbate this diastolic depolarization, thus promoting "hyperexcitability" or "automatic" ectopy. When myocardium is damaged, characteristically with myocardial ischemia, rapid conduction of cardiac impulses may be slowed dramatically. Very slow impulses may course through muscle such that by the time the activation wave front returns to the initiating site, this origin has had a chance to repolarize. This is the basis for re-entrant dysrhythmias. All cardiac dysrhythmias are automatic, re-entrant or both.
Topics: Arrhythmias, Cardiac; Electrocardiography; Emergencies; Humans
PubMed: 3295014
DOI: 10.1016/0736-4679(87)90075-8 -
Science (New York, N.Y.) Nov 2014The conversion of optical power to an electric potential is of general interest for energy applications and is typically obtained via optical excitation of semiconductor...
The conversion of optical power to an electric potential is of general interest for energy applications and is typically obtained via optical excitation of semiconductor materials. We developed a method for achieving electric potential that uses an all-metal geometry based on the plasmon resonance in metal nanostructures. In arrays of gold nanoparticles on an indium tin oxide substrate and arrays of 100-nanometer-diameter holes in 20-nanometer-thick gold films on a glass substrate, we detected negative and positive surface potentials during monochromatic irradiation at wavelengths below or above the plasmon resonance, respectively. We observed plasmoelectric surface potentials as large as 100 millivolts under illumination of 100 milliwatts per square centimeter. Plasmoelectric devices may enable the development of all-metal optoelectronic devices that can convert light into electrical energy.
PubMed: 25395532
DOI: 10.1126/science.1258405 -
Pharmaceutical Development and... Feb 2022Contact lens have been proposed as a mean of ocular drug delivery, but the conventional soaking method to load hydrophobic drugs, such as latanoprost shows low drug...
Contact lens have been proposed as a mean of ocular drug delivery, but the conventional soaking method to load hydrophobic drugs, such as latanoprost shows low drug loading and high burst release with alteration in the critical lens properties. In this paper, a novel latanoprost-loaded PEGylated solid lipid nanoparticles (LP-pSLNs) were developed to increase the latanoprost loading capacity of contact lenses (LP-pSLN-L), while also sustaining ocular drug delivery. The pSLNs were spherical in shape with an average size of 105‒132 nm (nanometer) and a zeta potential ranging from ‒29.1 to ‒26.7 mV (millivolt). The LP-pSLNs led to improved swelling, transmittance, and protein adherence of the lens compared to the non-pegylated SLNs congeners (LP-SLN-L) and conventional soaked lens (LP-SM-L). The LP-SM-L lens showed low drug loading, high burst release, and a short release duration of 24 h. The LP-SLN-L and LP-pSLN-L lenses showed high drug uptake and sustained drug release up to 120 h and 96 h, respectively. The pegylation reduced the size of nanoparticles and improved the drug loading capacity, while the release rate was high in the initial hours. The LP-pSLN-L lens was found to be safe based in histopathological studies. In animal studies, the LP-pSLN-10-L batch showed high drug concentration at all-time points up to 96 h compared to the LP-SM-L and eye drop solution. In conclusion, pSLNs improved the latanoprost loading in the contact lens and showed sustained drug release, and thus can be used as a substitute to eye drop therapy.
Topics: Animals; Contact Lenses, Hydrophilic; Drug Delivery Systems; Glaucoma; Latanoprost; Liposomes; Nanoparticles; Ophthalmic Solutions; Polyethylene Glycols
PubMed: 34704874
DOI: 10.1080/10837450.2021.1999471 -
European Journal of Pharmaceutical... Jan 2013Non-viral gene therapy represents a promising approach for the treatment of retinal diseases. However, the lack of an efficient carrier hampers the implementation of...
Non-viral gene therapy represents a promising approach for the treatment of retinal diseases. However, the lack of an efficient carrier hampers the implementation of this therapy. In this study, we evaluated low molecular weight ultrapure oligochitosans for the delivery of the pCMS-EGFP plasmid into the rat retina cells after subretinal and intravitreal administrations. Polyplexes were technologically characterized. Resulting polyplexes based on ultrapure oligochitosans were slightly spherical, protected the plasmid against enzymatic digestion, and their charge and size values ranged from 8 to 14 millivolts and from 150 to 69 nm respectively depending on the N/P ratio. In HEK-293 cultured cells, transfection efficiency significantly increased from 12% to 30% when pH decreased from 7.4 to 7.1 (data normalized to Lipofectamine™ 2000). However, no significant transfection was detected in ARPE-19 cultured cells. Subretinal administrations transfected mainly the pigmented cells of the retinal pigment epithelium and the light sensitive photoreceptor cells, whereas intravitreal injections transfected cells in the ganglion cell layer, blood vessels in the inner layers of the retina and photoreceptors. These results support the potential use of oligochitosans for delivering genetic material into retinal cells in vivo.
Topics: Animals; Cell Line; Chitin; Chitosan; DNA; Genetic Therapy; Genetic Vectors; Green Fluorescent Proteins; HEK293 Cells; Humans; Male; Oligosaccharides; Plasmids; Rats; Rats, Sprague-Dawley; Retina
PubMed: 23201002
DOI: 10.1016/j.ejps.2012.11.009 -
Frontiers in Veterinary Science 2022Personalized healthcare technology has grown explosively through the use of portable and smart monitoring devices for diagnosis. The objective of this study was to...
BACKGROUND
Personalized healthcare technology has grown explosively through the use of portable and smart monitoring devices for diagnosis. The objective of this study was to determine the practicality and usability of the Equimetre fitness tracker on camels in comparison to the standard base-apex system in normal and clinical cases.
METHODS
Five apparently healthy adult camels, five clinical adult cases and two clinical calves were enrolled in this study. The camels were equipped with two monitoring systems: Equimetre and a standard base-apex electrocardiogarphy. Each tracing was evaluated for the normal ECG variable's measure, including heart rate beats per min, P-R, QRS, R-R, Q-T, S-T intervals, and P-R and S-T segments in seconds. The amplitudes for P, Q, R, S, and T-peaks were evaluated in millivolts.
RESULTS
Equimetre showed stability on ECG tracing with less movement artifacts compared with the standard base-apex system. Different polarities were observed for the P-waves and T-waves between the standard base-apex system and Equimetre. Both devices showed perfect agreement for heart rate (ICC = 1.00, ≥ 0.0001, 95% = 1.00-1.00) in healthy and clinical adults. A good correlation was observed for the R-R interval between the devices in healthy and clinical adults. A moderate correlation was observed between the devices for Q-peak in clinical adults, with no correlation in clinical calves.
CONCLUSIONS
This study demonstrated acceptable ECG measurements between the standard base-apex and Equimetre device. This suggests that Equimetre could be a useful device in camels for initial electrocardiographic examinations in remote areas such as deserts.
PubMed: 36713881
DOI: 10.3389/fvets.2022.963732 -
Nature Jul 2012The spin Seebeck effect is observed when a thermal gradient applied to a spin-polarized material leads to a spatially varying transverse spin current in an adjacent...
The spin Seebeck effect is observed when a thermal gradient applied to a spin-polarized material leads to a spatially varying transverse spin current in an adjacent non-spin-polarized material, where it gets converted into a measurable voltage. It has been previously observed with a magnitude of microvolts per kelvin in magnetically ordered materials, ferromagnetic metals, semiconductors and insulators. Here we describe a signal in a non-magnetic semiconductor (InSb) that has the hallmarks of being produced by the spin Seebeck effect, but is three orders of magnitude larger (millivolts per kelvin). We refer to the phenomenon that produces it as the giant spin Seebeck effect. Quantizing magnetic fields spin-polarize conduction electrons in semiconductors by means of Zeeman splitting, which spin-orbit coupling amplifies by a factor of ∼25 in InSb. We propose that the giant spin Seebeck effect is mediated by phonon-electron drag, which changes the electrons' momentum and directly modifies the spin-splitting energy through spin-orbit interactions. Owing to the simultaneously strong phonon-electron drag and spin-orbit coupling in InSb, the magnitude of the giant spin Seebeck voltage is comparable to the largest known classical thermopower values.
PubMed: 22785317
DOI: 10.1038/nature11221 -
Journal of Neural Engineering Apr 2012We have previously described the use of microchannels (μChannels) as substrate-integrated equivalents of micropipettes and advantageous neuron-electrode interface...
We have previously described the use of microchannels (μChannels) as substrate-integrated equivalents of micropipettes and advantageous neuron-electrode interface enhancers. The use of μChannels to establish stable recording and stimulation of threading axons results in a high signal-to-noise ratio (SNR), potentially high-throughput and low-cost alternative to conventional substrate-embedded microelectrodes. Here we confirm the consistent achievement of high SNRs with μChannels and systematically characterize the impact of μChannel geometry on the measured signals via numerical simulations and in vitro experiments. We demonstrate and rationalize how channels with a length of ≤300 μm and channel cross section of ≤12 μm(2) support spontaneous formation of seals and yield spike sizes in the millivolt range. Despite the low degree of complexity involved in their fabrication and use, μChannel devices provide a single-unit mean SNR of 101 ± 76, which compares favourably with the SNR obtained from typical microelectrode arrays.
Topics: Algorithms; Animals; Axons; Biophysics; Cells, Cultured; Computer Simulation; Electric Impedance; Electric Stimulation; Electrophysiology; Equipment Design; Female; Hippocampus; Immunohistochemistry; Linear Models; Membrane Potentials; Mice; Microelectrodes; Microscopy, Electron; Microscopy, Fluorescence; Neurons; Pregnancy; Signal-To-Noise Ratio
PubMed: 22333069
DOI: 10.1088/1741-2560/9/2/026010 -
Advanced Materials (Deerfield Beach,... May 2024Integration of molecular switching units into complex electronic circuits is considered to be the next step towards the realization of novel logic and memory devices....
Integration of molecular switching units into complex electronic circuits is considered to be the next step towards the realization of novel logic and memory devices. Here, we report on an ordered 2D network of neighboring ternary switching units represented by triazatruxene (TAT) molecules organized in a honeycomb lattice on a Ag(111) surface. Using low-temperature scanning tunneling microscopy, we are able to control the bonding configurations of individual TAT molecules within the lattice, realizing up to 12 distinct states per molecule. The switching between those states shows a particularly strong bias dependence ranging from tens of millivolts to volts. Based on a single TAT molecule as a fundamental building block, we then explore the low-bias switching behavior in units consisting of two and more interacting TAT molecules purposefully defined by the high-bias switching within the honeycomb lattice. we demonstrate the possibility to realize up to 9 and 19 distinguishable states in a dyad and a tetrad of coupled switching units, respectively. The switching dynamics can be triggered and accessed by single-point measurements on a single molecule. High experimental control over the desired state, owing to hierarchical switching and pronounced switching directionality, as well as the observed full reversibility, makes this system particularly appealing, paving the way to design complex molecule-based memory systems. This article is protected by copyright. All rights reserved.
PubMed: 38749066
DOI: 10.1002/adma.202401662