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Cells are routinely exposed to agents that cause plasma membrane (PM) injury. While pore‐forming toxins (PFTs), and chemicals cause nanoscale holes dispersed throughout the PM, mechanical trauma causes focal lesions in the PM. To examine if these distinct injuries share common repair mechanism, membrane trafficking is monitored as the PM repairs from such injuries. During the course of repair, dispersed PM injury by the PFT Streptolysin O activates endocytosis, while focal mechanical injury to the PM inhibits endocytosis. Consequently, acute block of endocytosis prevents repair of diffuse, but not of focal injury. In contrast, a chronic block in endocytosis depletes cells of early endosomes and inhibits repair of focal injury. This study finds that both focal and diffuse PM injury activate Ca2+‐triggered exocytosis of early endosomes. The use of markers including endocytosed cargo, Rab5, Rab11, and VAMP3, all reveal injury‐triggered exocytosis of early endosomes. Inhibiting Rab5 prevents injury‐triggered early endosome exocytosis and phenocopies the failed PM repair of cells chronically depleted of early endosomes. These results identify early endosomes as a Ca2+‐regulated exocytic compartment, and uncover the requirement of their dual functions – endocytosis and regulated exocytosis, to differentially support PM repair based on the nature of the injury. [ABSTRACT FROM AUTHOR]

The anatase phase of TiO2 is highly suitable for photocatalytic application consequently, prerequisite an unpretentious scale‐independent understanding of its roughening‐facilitated surface topography dynamics. Herein, the nonlinear roughening in anatase thin films and its correlation with the nonlinear trend of optical properties in the framework of fractal geometry are investigated. The self‐affine nature of analyzed surfaces is confirmed from the autocorrelation function. The dynamic scaling exponents indicate the existence of Kardar–Parisi–Zhang scaling in surface growth. In addition, the trend of generalized Hurst exponent and mass exponent indicates insignificant multifractal characteristics in the analyzed surfaces. Moreover, fractal analysis explains and aids to description of roughening trend from stereometric and Minkowski functionals analysis. Furthermore, the significance of fractal dimension for probing the surface roughening is validated from the principal component analysis. Consequently, variation in optical bandgap and linear refractive index are investigated in regards to the fractal dimension and root mean‐squared surface slope and regression equations are proposed for tuning of bandgap. [ABSTRACT FROM AUTHOR]

In this article, we have studied the detailed electrical and optical characteristics of crystalline α-, γ-, and α + γ-manganese sulfide (MnS) thin films. Highly ordered thin films of α-, γ-, and α + γ-MnS were prepared by direct current reactive sputtering on glass substrates at different substrate temperatures (room temperature to 400 °C) while maintaining other parameters at optimized values. The X-ray diffraction measurement revealed the synthesis of γ-, α + γ-, and α-phase of MnS thin films with preferred orientations (002), (002) + (200), and (200), respectively. The morphological and topographical results demonstrated that the particle size as well as the average roughness of MnS samples varied as a linear function of the substrate temperature. The x-ray photoelectron spectroscopy study revealed that the γ-MnS sample prepared at room temperature has the lowest oxygen related vacancy (12.7%). The optical characteristics such as refractive index n, extinction coefficient k, and optical bandgap Eg are determined in the broad wavelength range of 246–688 nm using spectroscopic ellipsometry. Moreover, the nonlinear refractive index n2 and the third-order nonlinear optical susceptibility χ(3) are determined using the Tichy–Ticha relation and Wemple–Didomenico parameters. The ratio of the carrier concentration to the effective mass N/m* has also been determined, indicating best electrical properties for γ-MnS films. The current research on the optical and electrical properties of highly ordered α-, γ-, and α + γ-MnS thin films is expected to have a significant impact on advanced optoelectronic, photonic, and energy applications. [ABSTRACT FROM AUTHOR]

In this work, we have reported the in-situ fabrication of nanocrystalline rhombohedral silicon carbide (15R-SiC) thin films by RF-magnetron sputtering at 800 °C substrate temperature. The structural and optical properties were investigated for the films grown on four different substrates (ZrO2, MgO, SiC, and Si). The contact angle measurement was performed on all the substrates to investigate the role of interfacial surface energy in nucleation and growth of the films. The XRD measurement revealed the growth of (1 0 10) orientation for all the samples and demonstrated better crystallinity on Si substrate, which was further corroborated by the TEM results. The Raman spectroscopy confirmed the growth of rhombohedral phase with 15R polytype. Surface characteristics of the films have been investigated by energy dispersive x-ray spectroscopy, FTIR, and atomic force microscope (AFM) to account for chemical composition, bonding, and root mean square surface roughness (δrms). The optical dispersion behavior of 15R-SiC thin films was examined by variable angle spectroscopic ellipsometry in the wide spectral range (246-1688 nm), including the surface characteristics in the optical model. The non-linear optical parameters (χ³ and n2) of the samples have been calculated by the Tichy and Ticha relation using a single effective oscillator model of Wemple and Didomenico. Additionally, our optical results provided an alternative way to measure the ratio of carrier concentration to the effective mass (N/m*). These investigated optical parameters allow one to design and fabricate optoelectronic, photonic, and telecommunication devices for deployment in extreme environment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fucoxanthin is a hydrophobic carotenoid with many beneficial biological activities. However, due to low aqueous solubility their clinical efficacy is limited thus leading to poor oral bioavailability. To address this issue, we encapsulated fucoxanthin in rhamnolipid fabricated bovine serum albumin (BSA) loaded nanoparticles (LNPs) for improving solubility dependent bioavailability of fucoxanthin. RESULTS: These synthesized LNPs were characterized by dynamic light scattering (DLS), ultraviolet (UV)‐visible spectrophotometry, high‐performance liquid chromatography (HPLC), Fourier‐transform infrared (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC). Our results showed that LNPs were spherical in shape with particle size around 180 nm along with positive zeta potential. The encapsulation efficiency and loading efficiency calculated for LNPs were 69.66 ± 1.5% and 14 ± 0.2%, respectively. The antioxidant assay of LNPs indicate high radical scavenging activity compared to pure fucoxanthin. Besides this, our release studies indicates that drug release occur from the matrix of nanocarrier system through diffusion based on concentration. Thus, these findings indicate successful encapsulation of fucoxanthin, with improved solubility thereby leading to increased bioavailability. This nano formulation is derived from components which are FDA approved that could be exploited for encapsulating other vital nutraceutical molecules. CONCLUSION: Overall, our results showed successful synthesis of biodegradable nanocarrier for delivering fucoxanthin supported by molecular docking, molecular dynamics simulation and thermodynamics of free binding energy studies. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Hardness of thin films is a noteworthy property in the electronic and mechanical industry and is generally observed to be dependent on the degree of roughening facilitated from surface heights' surface spatial heterogeneity at the mesoscopic observation scale. Nonetheless, owing to enhanced scale fluctuations and higher-order central moments, conventional parameters provide limitations and errors in capturing the spatial heterogeneity of surfaces. Herein, we have utilized scale-independent fractal parameters to analyze the spatial heterogeneity of surface heights in Ti1−xSixN ternary hard films deposited with varying Si doping concentrations using sputtering technique. The fractal dimension, lacunarity coefficient, Moran index, surface entropy, Otsu's separability, and fractal succolarity were computed to provide an overarching understanding of the surface heights' spatial heterogeneity. Principal component analysis was employed on the data sets to identify the parameter(s) accounting for the maximum variance and accordingly, the structure–property relation between spatial heterogeneity of surface and hardness is analyzed and discussed in the context of the fractal dimension of surface heights. The results indicate the possibility of mesoscopic surface engineering and, consequently, tuning of hardness and modulus of elasticity in Ti1−xSixN hard films by mere changing of surface spatial heterogeneity facilitated by the fractal dimension of surface heights. [ABSTRACT FROM AUTHOR]

Highly ordered and hydrophobic zinc oxide thin films have been synthesized by dc magnetron sputtering on the glass substrates at room temperature (RT). We have determined the influence of deposition parameters on the optical and other physical properties of the films, and the correlation between their microstructural and optical properties. Films have preferred (002) orientation, an average crystallite size ≤26 nm, and rms surface roughness ≤14 nm. The water contact angle of 120°exceeds previous measurements by over 10°–20°. Dispersion of the refractive index is analyzed in terms of the Wemple-DiDomenical single-oscillator model, and the third-order nonlinear optical parameters are calculated using the Tichy and Ticha relation. Refractive indices of 1.9686 at 540 nm are near the bulk value of 2.0041. Produced at RT, these highly ordered films may be promising candidates for compact optoelectronic devices. [ABSTRACT FROM AUTHOR]

• Design and fabrication of flexible on-skin wearable pH sensors using Sb 2 O 3 /Sb and AgIO 3 /Ag electrodes. • Analysis of microstructural and compositional properties of both electrodes by FESEM, XPS and XRD. • Remarkable sensitivity of −54.29 mV/pH and a linear pH response (R 2 ∼ 0.99) over a wide pH range of 1.68–9.18. • Verification of sweat detection ability by collecting sweat from different parts of the body like fingers, chest, soles and armpits. • Successful demonstration of real-time sweat sensing on forehead and back after indoor exercise. This study presents a significant advancement in the application of a freestanding potentiometric pH sensor patch made of PDMS, incorporating a sensing electrode of Sb 2 O 3 /Sb thin film and a reference electrode of AgIO 3 /Ag thin film. The pH sensing electrodes of Sb 2 O 3 /Sb/Au/Ni and AgIO 3 /Ag/Au/Ni thin films were deposited over the PDMS/cellulose acetate/Si substrate using the ECR/RF sputtering technique. The pH sensor prepared on the PDMS/cellulose acetate/Si substrate displayed excellent sensitivity (−58.24 to −60.84 mV/pH, n = 4) and a robust linear response (R 2 ∼ 0.99) in a wider pH range (1.68–9.18). The flexible on-skin wearable pH sensors were obtained by peeling off the pH sensor-assisted PDMS sheet from the Si substrate, which exhibited a remarkable sensitivity of -54.29 mV/pH and a linear pH response (R 2 ∼ 0.99). Real-time sweat sensing experiments confirmed the accuracy of the developed flexible on-skin wearable pH sensors in monitoring pH levels at different body parts. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A microfluidic pH sensing chip was developed using Sb 2 O 3 /Sb and AgIO 3 /Ag thin films. • The PDMS microfluidic channel was prepared using a 3D-printed mold. • The sensing chip was studied using FESEM, XRD, Raman, XPS, and 3D laser microscope. • The chip exhibited good sensitivity of −57.02 ± 1.23 mV/pH, with n = 4 replicates. • In-vitro pH testing with A549 cells validated chip's real-time pH measurement. In this study, we present the fabrication and characterization of a microfluidic pH sensing chip designed to detect human lung cancer (A549) cells. The chip utilizes a Sb 2 O 3 /Sb thin film as the working electrode and an AgIO 3 /Ag thin film as the reference electrode, both deposited using the radio frequency (RF) sputtering technique. The PDMS microfluidic channel was prepared using a 3D-printed mold, followed by curing of PDMS within the mold. The fabricated sensing chip demonstrated excellent linear response (R2 ∼ 0.99) and appreciable Nernstian sensitivity (average = -57.02 ± 1.23 mV/pH, n = 4) in a wide pH range of 1.68–10.01. It exhibited good stability over a 48-hour duration with acceptable drift voltage and negligible temperature impact on the sensing performance. Further, in-vitro pH testing of human lung cancer (A549) cells was performed to investigate the real-time pH measurement ability of the developed microfluidic pH sensing chip. [ABSTRACT FROM AUTHOR]

Breast cancer is a major cause of death in women worldwide leading to requirement of new therapeutic strategies. Silymarin demonstrated the anti-cancer activity however, due to low bioavailability its use is restricted. This study aimed to improve the solubility of silymarin by developing a silymarin loaded zein nanoparticles (SLNPs) which was stabilized by beta cyclodextrin. Comprehensive physiochemical characterization studies based on DLS, FTIR, UV–Vis Spectroscopy, FE-SEM, TEM, XRD, DSC, NMR and TGA confirmed the successful synthesis of SLNPs via an anti-solvent precipitation method. FE-SEM and TEM images demonstrated the uniform size and spherical shape of nanoparticles with encapsulation and loading efficiencies of 84.32 ± 1.9 % and 15.25 ± 2.4 % respectively. The zein protein interaction with silymarin, and β-cyclodextrin was shown to be beneficial via the use of molecular simulations and binding energy calculations. Cellular studies demonstrated dose and time dependent cytotoxicity of SLNPs on MCF-7 breast cancer cell. FACS, qRT-PCR and Western blotting showed Bax (pro-apoptotic) upregulation while Bcl-2 (anti-apoptotic) downregulation. Our findings suggest that these loaded nanoparticles are more efficient than pure drug, enhancing its bioavailability and paving the path for developing it as a promising nutraceutical to treat breast cancer. [Display omitted] • Nanoencapsulation of silymarin notably enhanced the solubility and stability of silymarin. • FE-SEM and TEM images demonstrated the uniform size and spherical shape of nanoparticles. • The anticancer efficacy of silymarin effectively improved through nanoencapsulation. • The encapsulation and loading efficiencies were 84.32 ± 1.9 % and 15.25 ± 2.4 % respectively. • Western blotting showed Bax upregulation while Bcl-2 downregulation. [ABSTRACT FROM AUTHOR]

Mitochondria are central to the health of eukaryotic cells. While commonly known for their bioenergetic role, mitochondria also function as signaling organelles that regulate cell stress responses capable of restoring homeostasis or leading the stressed cell to eventual death. Damage to the plasma membrane is a potentially fatal stressor incurred by all cells. Repairing plasma membrane damage requires cells to mount a rapid and localized response to injury. Accumulating evidence has identified a role for mitochondria as an important facilitator of this acute and localized repair response. However, as mitochondria are organized in a cell-wide, interconnected network, it is unclear how they collectively sense and respond to a focal injury. Here we will discuss how mitochondrial shape change is an integral part of this localized repair response. Mitochondrial fragmentation spatially restricts beneficial repair signaling, enabling a localized response to focal injury. Conservation of mitochondrial fragmentation in response to cell and tissue damage across species demonstrates that this is a universal pro-survival adaptation to injury and suggests that mitochondrial fragmentation may provide cells a mechanism to facilitate localized signaling in contexts beyond repairing plasma membrane injury. [ABSTRACT FROM AUTHOR]

Reverse transcription-quantitative PCR (RT-qPCR)-based assays are extensively being utilized to detect coronavirus disease 2019 (COVID-19). However, due to a lack of RT-qPCR testing capability, these tests cannot be carried out in community clinics. The intention of our study was to evaluate the specificity and sensitivity of Rapid Antigen Detection (RAT) tests versus those of RT-qPCR using nasopharyngeal and oropharyngeal specimens. Respiratory swab specimens were collected from the COVID-19 patients admitted at Dr. Bhimrao Ambedkar Memorial Hospital, Raipur, CG, India, during March to April 2022. RAT and RT-qPCR were performed using standard methods as per guidebook instructions, and subjects were chosen using a convenience sample technique. 100 swabs from patients, who had earlier verified positive and 100 from who had earlier verified negative for SARS-CoV-2 via RT-qPCR, were taken for study. Study was approved by the institutional ethical committee before data collection and initiation of the study. We evaluated for the sensitivity and specificity of the STANDARD Q COVID-19 Ag test kit (SD Biosensor). On testing, an over-all sensitivity and specificity of the kit was recorded as 74% and 100%, respectively in comparison to the RT-qPCR kit. Further, the assay's sensitivity was shown to be 100%, 94.87%, 77.27%, and 55.56%, respectively, for samples with cycle thresholds (Ct) of 15-25, 25-30, 30- 35, and >35. We draw the conclusion that the RT-qPCR assay has superior sensitivity and specificity to the antigen assay. However, in all situations where RT-qPCR testing is difficult, the antigen assay could serve as a rapid and simple option for separating SARS-CoV-2 contagious from non-contagious patients. [ABSTRACT FROM AUTHOR]

Abstract Fundamental aspects of poly- l -lysine (PLL) coated silver nanoparticles (AgNPs) are presented for their possible use in colorimetric sensing of heavy metal ions. For this purpose, cetyltrimethylammonium bromide (CTAB) is used, which acts as a stabilizing agent. At the molecular level, the adsorption behavior of PLL and CTAB is evaluated from first principles calculations. These studies demonstrate that PLL and CTAB interact with Ag cluster through NH 2 group and positively charged trimethylammonium group, respectively. Surface adsorption of PLL and CTAB on AgNPs is studied under the effect of temperature and reaction time. Multidisciplinary approaches including UV–Visible absorption spectroscopy, Fourier-Transformed Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM) are conducted to systematically investigate PLL coated AgNPs stabilized by CTAB (PL-CT-AgNPs). Thus, a combination of experimental and theoretical analysis helped us to identify specific sites, which promoted such interactions for surface adsorption on AgNPs. As synthesized PL-CT-AgNPs, are found to be highly sensitive and selective towards Hg2+ detection. The mechanism of detection of Hg2+ is studied on PL-CT-AgNPs surface using Density Functional Theory (DFT). Highlights • DFT theory helps us in understanding high affinity of PLL and CTAB with AgNPs. • AgNPs are synthesized in the presence of PLL and stabilized by CTAB. • Synthesized AgNPs are highly selective for the detection of Hg2+ in water. • Mechanism of sensing of Hg2+ on the surface of AgNPs is explained using DFT. [ABSTRACT FROM AUTHOR]

This article, published in Advanced Science, discusses the role of early endosomes in repairing plasma membrane injuries in cells. The authors present findings that demonstrate how a specific population of early endosomes within the cell quickly fuses with the injured membrane to facilitate successful repair. The study highlights the importance of these early endosomes in repairing different types of injuries, including those caused by bacterial toxins and mechanical damage. For more information, readers can refer to the full article by Daniel C. Bittel and Jyoti K. Jaiswal. [Extracted from the article]

Plasma membrane forms the barrier between the cytoplasm and the environment. Cells constantly and selectively transport molecules across their plasma membrane without disrupting it. Any disruption in the plasma membrane compromises its selective permeability and is lethal, if not rapidly repaired. There is a growing understanding of the organelles, proteins, lipids, and small molecules that help cells signal and efficiently coordinate plasma membrane repair. This review aims to summarize how these subcellular responses are coordinated and how cellular signals generated due to plasma membrane injury interact with each other to spatially and temporally coordinate repair. With the involvement of calcium and redox signaling in single cell and tissue repair, we will discuss how these and other related signals extend from single cell repair to tissue level repair. These signals link repair processes that are activated immediately after plasma membrane injury with longer term processes regulating repair and regeneration of the damaged tissue. We propose that investigating cell and tissue repair as part of a continuum of wound repair mechanisms would be of value in treating degenerative diseases. [ABSTRACT FROM AUTHOR]

We utilized fractal geometry to advance insights into the complex roughening and its facilitated wettability mechanism of sputtered MoS 2 film surfaces with varying thickness are studied. Fractal parameters indicate the dominance of shadowing at lower thickness while enhancement in vertical growth rate and variation in local irregularities are observed at higher thicknesses along with anomalous roughening up to thickness of 200 nm. In addition, anti-persistent trend of surface heights was observed to be independent of thickness. Multifractal analysis exposed the non-linear variation in multifractality strength and vertical complexities of surface heights. The results corroborates the stereometric analysis revealing the 3D surface topography of analyzed films. The wettability was observed to increase with thickness. In consideration, the roughening expedited wetting trend is defined in light of stereometric parameters and multifractility strength suggesting increases the penetration of water droplets into the surface voids with decline in the surface complexities. The mechanism for increase in contact angle is realized from the augmentation in curvature pressure indicating the existence of large air pressure within the void lying lower than the water droplets as compared to the pressure from the meniscus sides of the droplets. In addition, principal component analysis is utilized to reveal the significance of fractal parameters in probing the surface roughening. The results hold prospects in surface engineering of MoS 2 thin films as a function of thickness for enhanced catalytic activity in electrochemical splitting of water for hydrogen evolution reactions. • The wetting mechanism in MoS 2 thin films was realized from curvature pressure. • Principal component analysis validated the significance of fractal parameters. • Multifractal parameters exhibited non-linearity with increasing thickness. • Dominance of shadowing was realized for lower thickness MoS 2 surfaces. • Anti-persistence behavior of surface heights was observed for all depositions. [ABSTRACT FROM AUTHOR]

This work reports room temperature operable ultrasensitive NO 2 gas sensors fabricated from vertically aligned crystalline MoSe 2 porous nanowall thin films prepared by a facile and scalable DC sputtering technique at room temperature without any post-annealing and selenization treatment. The microstructural and compositional studies were carried out using XRD, Raman, FESEM, HRTEM, EDS and XPS to identify the quality and properties of the deposited MoSe 2 thin films and to realize the underlying gas sensing mechanism. The NO 2 gas sensing performance of vertically aligned MoSe 2 porous nanowall thin film sensors was recorded over a wide range of NO 2 gas concentrations (0.1–50 ppm) at room temperature (30 °C). The fabricated sensing device based on grown MoSe 2 thin film exhibits excellent sensing characteristics (relative sensor response = –78.3% and response/ recovery time ~ 20 s/ 174 s for 10 ppm NO 2 gas) along with high selectivity, real-time response, rapid on-off switching and adequate stability at room temperature. The observed substantial enhancement in sensing performance is attributed to the superior charge transfer process as a consequence of augmented adsorption of gas molecules mediated by the higher surface-to-volume ratio of the unique nanostructure, i.e., edge-enriched crystalline MoSe 2 nanowalls along with the 3D porous surface structure in addition to the significant catalytic activity of MoSe 2. Thus, this uniquely developed highly nanocrystalline sputtered MoSe 2 porous nanowall thin films with vertically aligned molecular layers deposited at room temperature is cost-effective and highly desirable for developing low-powered high-performance gas sensors. [Display omitted] • Room temperature growth of vertically aligned crystalline MoSe 2 porous nanowall thin films by DC sputtering. • SEM, TEM, XRD, Raman, XPS & EDX endorsed the formation of vertically aligned crystalline MoSe 2 porous nanowall thin films. • NO 2 gas sensing characteristics and sensing mechanism of the grown MoSe 2 thin films were investigated comprehensively. • Vertically aligned crystalline MoSe 2 porous nanowall thin films showed superb NO 2 gas sensing properties at RT. [ABSTRACT FROM AUTHOR]

Insights into the fundamentals of structure-property relations are one of the most important key parameters, which can be utilized for tailoring material properties such as electrical, and optical for the photonics, optoelectronics, energy storage, and sensing devices. Herein, we report a controlled single-step, large area growth of highly crystalline vertically grown edge exposed MoS 2 thin films using DC magnetron sputtering. To understand a correlation between microstructural and material properties, we have prepared MoS 2 films of different thicknesses (∼1 nm–440 nm) by varying sputtering deposition times (DT = 1 s–10 min). We have attempted to augment our prevailing understanding of structure-property relations of MoS 2 in order to provide large tunability in the optical and electrical properties. Spectroscopic ellipsometry results suggest that the complex refractive index (n and k), dielectric function (Ɛ 1 and Ɛ 2), and optical bandgap (E g = 1.35–1.88 eV) are highly dependent on MoS 2 film thickness. The MoS 2 electrical resistance was observed in the range of ∼15 kΩ–98 MΩ, displaying an inverse relationship with the film thickness. • Highly crystalline MoS 2 thin film in the thickness range of ∼1 nm–440 nm, have been prepared by DC sputtering method. • XRD, XPS, Raman, SEM and TEM investigation confirmed the formation of high quality MoS 2 thin film. • XPS results revealed the fabricated MoS 2 samples are S deficient with some amount of oxygen impurities. • SE investigation suggested the optical bandgap (E g = 1.35–1.88 eV) is strongly dependent on MoS 2 film thickness. • The resistance of the MoS 2 films was found to be highly dependent on film thickness, and observed in the range of ∼15 kΩ–98 MΩ. [ABSTRACT FROM AUTHOR]

Abstract: We have been following clinically and with muscle MRI for the past 3-decades a Finnish family with two patients with distal muscular dystrophy. Previously we demonstrated the cellular defect in these patients to be defective membrane repair and more recently have identified the causative gene to be anoctamin 5 (ANO5). The disorder seen in these patients is characterized by onset in the third decade. First symptoms were burning sensation on the calves and later on calf tightness during running. Muscle weakness and wasting were asymmetric and early involving the calf muscles, later spread to the thigh muscles. Biceps brachi was later manifestation. Clinical course was slow. CK levels were high. Muscle biopsy showed dystrophic pattern and multifocal disruption of the sarcolemmal membrane but no subsarcolemmal vesicle accumulation nor active inflammation. We conclude that the disease seen in our cases is a new separate clinical, genetic and histopathologic entity to include within the classification of autosomal recessive distal muscular dystrophies. [ABSTRACT FROM AUTHOR]

Optical imaging of individual vesicle exocytosis is providing new insights into the mechanism and regulation of secretion by cells. To study calcium-triggered secretion from astrocytes, we used acridine orange (AO) to label vesicles. Although AO is often used for imaging exocytosis. we found that imaging vesicles labeled with AO can result in their photolysis. Here, we define experimental and analytical approaches that permit us to distinguish unambiguously between fusion, leakage, and lysis of individual vesicles. We have used this approach to demonstrate that lysosomes undergo calcium-triggered exocytosis in astrocytes. [ABSTRACT FROM AUTHOR]

The ability to sense and respond to the environment is a hallmark of living systems. These processes occur at the levels of the organism, cells and individual molecules. Sensing of extracellular changes could result in a structural or chemical alteration in a molecule, which could in turn trigger a cascade of intracellular signals or regulated trafficking of molecules at the cell surface. These and other such processes allow cells to sense and respond to environmental changes. Often, these changes and the responses to them are spatially and/or temporally localized, and visualization of such events necessitates the use of high-resolution imaging approaches. Here we discuss optical imaging approaches and tools for imaging individual events at the cell surface with improved speed and resolution. [ABSTRACT FROM AUTHOR]

Two autosomal recessive muscle diseases, limb girdle muscular dystrophy type 2B (LGMD2B) and Miyoshi myopathy (MM), are caused by mutations in the dysferlin gene. These mutations result in poor ability to repair cell membrane damage, which is suggested to be the cause for this disease. However, many patients who share clinical features with MM-type muscular dystrophy do not carry mutations in dysferlin gene. To understand the basis of MM that is not due to mutations in dysferlin gene, we analyzed cells from patients in one such family. In these patients, we found no defects in several potential candidates – annexin A2, caveolin-3, myoferlin and the MMD2 locus on chromosome 10p. Similar to dysferlinopathy, these cells also exhibit membrane repair defects and the severity of the defect correlated with severity of their disease. However, unlike dysferlinopathy, none of the conventional membrane repair pathways are defective in these patient cells. These results add to the existing evidence that cell membrane repair defect may be responsible for MM-type muscular dystrophy and indicate that a previously unsuspected genetic lesion that affects cell membrane repair pathway is responsible for the disease in the non-dysferlin MM patients. [ABSTRACT FROM AUTHOR]

Discusses the use of quantum dots for live cell imaging by researchers from the U.S. Significance of monitoring interactions within and among cells as they grow and differentiate on the understanding of organismal development; Reasons behind the preference of clinicians on fluorescence microscopy for high-resolution, noninvasive imaging of live organisms; Advantages of using fluorescent quantum dots over conventional systems during live cell imaging.

Metastasis is an impediment to the development of effective cancer therapies. Our understanding of metastasis is limited by our inability to follow this process in vivo. Fluorescence microscopy offers the potential to follow cells at high resolution in living animals. Semiconductor nanocrystals, quantum dots (QDs), offer considerable advantages over organic fluorophores for this purpose. We used QDs and emission spectrum scanning multiphoton microscopy to develop a means to study extravasation in vivo. Although QD labeling shows no deleterious effects on cultured cells, concern over their potential toxicity in vivo has caused resistance toward their application to such studies. To test if effects of QD labeling emerge in vivo, tumor cells labeled with QDs were intravenously injected into mice and followed as they extravasated into lung tissue. The behavior of QD-labeled tumor cells in vivo was indistinguishable from that of unlabeled cells. QDs and spectral imaging allowed the simultaneous identification of five different populations of cells using multiphoton laser excitation. Besides establishing the safety of QDs for in vivo studies, our approach permits the study of multicellular interactions in vivo. [ABSTRACT FROM AUTHOR]

Fluorescent semiconductor nanocrystals, known as quantum dots (QDs), have several unique optical and chemical features. These features make them desirable fluorescent tags for cell and developmental biological applications that require long-term, multi-target and highly sensitive imaging. The improved synthesis of water-stable QDs, the development of approaches to label cells efficiently with QDs, and improvements in conjugating QDs to specific biomolecules have triggered the recent explosion in their use in biological imaging. Although there have been many successes in using QDs for biological applications, limitations remain that must be overcome before these powerful tools can be used routinely by biologists. [Copyright &y& Elsevier]

Synaptotagmin is considered a calcium-dependent trigger for regulated exocytosis. We examined the role of synaptotagmin VII (Syt VII) in the calcium-dependent exocytosis of individual lysosomes in wild-type (WT) and Syt VII knockout (KO) mouse embryonic fibroblasts (MEFs) using total internal reflection fluorescence microscopy. In WT MEFs, most lysosomes only partially released their contents, their membrane proteins did not diffuse into the plasma membrane, and inner diameters of their fusion pores were smaller than 30 nm. In Syt VII KO MEFs, not only was lysosomal exocytosis triggered by calcium, but all of these restrictions on fusion were also removed. These observations indicate that Syt VII does not function as the calcium-dependent trigger for lysosomal exocytosis. Instead, it restricts the kinetics and extent of calcium-dependent lysosomal fusion. [ABSTRACT FROM AUTHOR]

Synaptotagmin is considered a calcium-dependent trigger for regulated exocytosis. We examined the role of synaptotagmin VII (Syt VII) in the calcium-dependent exocytosis of individual lysosomes in wild-type (WT) and Syt VII knockout (KO) mouse embryonic fibroblasts (MEFs) using total internal reflection fluorescence microscopy. In WT MEFs, most lysosomes only partially released their contents, their membrane proteins did not diffuse into the plasma membrane, and inner diameters of their fusion pores were smaller than 30 nm. In Syt VII KO MEFs, not only was lysosomal exocytosis triggered by calcium, but all of these restrictions on fusion were also removed. These observations indicate that Syt VII does not function as the calcium-dependent trigger for lysosomal exocytosis. Instead, it restricts the kinetics and extent of calcium-dependent lysosomal fusion. Lysosomes only partially release their contents in wild-type mouse embryonic fibroblasts (MEFs); but in MEFs in which synaptotagmin VII has been deleted, lysosomes fuse completely. [ABSTRACT FROM AUTHOR]

Luminescent quantum dots (QDs) -- semiconductor nanocrystals-are a promising alternative to organic dyes for fluorescence-based applications. We have developed procedures for using QDs to label live cells and have demonstrated their use for long-term multicolor imaging of live cells. The two approaches presented are (i) endocytic uptake of QDs and (ii) selective labeling of cell surface proteins with QDs conjugated to antibodies. Live cells labeled using these approaches were used for long-term multicolor imaging. The cells remained stably labeled for over a week as they grew and developed. These approaches should permit the simultaneous study of multiple cells over long periods of time as they proceed through growth and development. [ABSTRACT FROM AUTHOR]

Describes the role of membrane proximal lysosomes for calcium-dependent exocytosis in nonsecretory cells. Repair of membrane ruptures; Recruitment of lysosomes to the cell surface; Neurotransmitter release.

• CdTe-functionalized ZnO and pristine ZnO hierarchical nanostructured thin film were deposited on porous Si substrate by sputtering. • Porous Si (PSi) substrate was prepared by electrochemical anodization method. • NO 2 gas sensing properties of CdTe/ZnO@PSi and ZnO@Psi thin film sensors were studied thoroughly. • CdTe/ZnO@PSi showed enhanced NO 2 gas sensing characteristics even at low temperature than those of ZnO@PSi. • NO 2 gas sensing mechanism of CdTe/ZnO@PSi thin film sensor was proposed comprehensively. In this report, we present improved NO 2 gas sensing properties based on CdTe-functionalized ZnO filled porous Si (PSi) hybrid hierarchical nanostructured thin films (CdTe/ZnO@PSi). The CdTe and ZnO nanostructured thin films were grown on the PSi substrate using a scalable magnetron sputtering technique. The PSi substrate was prepared using the electrochemical anodization method. The proposed CdTe/ZnO@PSi sensor was characterized in terms of structural, morphological, and compositional properties. The sensing performance and corresponding mechanism of NO 2 gas sensor based on CdTe/ZnO@PSi were described comprehensively. In order to compare, the sensing characteristics of both CdTe/ZnO@PSi and pristine ZnO@PSi thin film sensors were tested in different temperature range varied from 30 °C to 180 °C for 1 ppm concentration of NO 2 gas. We found that CdTe/ZnO@PSi sensor displays enhanced NO 2 sensing characteristics (∼3.5-fold greater sensor response ∼19.82 %, fast response/recovery time ∼13 s/54 s) at the relatively low working temperature of 90 °C towards 1 ppm NO 2 gas in comparison to the pristine ZnO@PSi sensor (sensor response ∼5.72 % and response/recovery time ∼41 s/124 s at an operating temperature of 150 °C). Further, the fabricated NO 2 gas sensor demonstrated excellent reversibility and good stability, and enabling CdTe/ZnO@PSi a promising candidate for its practical use in IoT sensing devices. [ABSTRACT FROM AUTHOR]

• Pd functionalized vertically aligned edge-oriented MoS 2 hybrid thin film was fabricated by sputtering. • H 2 gas sensing properties of Pd/MoS 2 hybrid thin film was studied systematically at RT. • H 2 gas sensing mechanism of Pd/MoS 2 hybrid thin film sensor was proposed comprehensively. • Pd/MoS 2 hybrid thin film sensor exhibited fast response/recovery time (16 s/38 s). The increasing use of hydrogen (H 2) as a clean energy carrier utilized in the next-generation fuels demand parallel development of low power hydrogen sensors (operated at room temperature) for safety purposes. In this work, we report a controlled single-step, large-area growth of vertically aligned edge-oriented MoS 2 hybrid nanostructured thin film decorated with Pd nanoparticles (Pd/MoS 2) on quartz and Si substrates using DC magnetron sputtering technique. The structural, morphological, and chemical characterizations were performed using XRD, Raman, FESEM, TEM, EDX, and XPS techniques, which confirms the formation of Pd/MoS 2 hybrid thin film. Hydrogen gas sensing characteristics of Pd/MoS 2 hybrid thin film sensor under low detection range (10−500 ppm) and proposed sensing mechanism are discussed in detail. To gain further insights into the gas sensing mechanism, we have studied the junction band alignment at the Pd/MoS 2 interface using ultraviolet photoelectron spectroscopy and ellipsometry. The results demonstrate that the fabricated Pd/MoS 2 hybrid thin film sensor exhibits highly enhanced H 2 sensing properties (decent response ∼33.7 %, fast response/recovery time ∼16 s/38 s, and higher selectivity) compared to pristine MoS 2 thin film sensor (poor response ∼1.2 % and slow response/recovery time ∼29 s/158 s, and poor selectivity) towards 500 ppm H 2 at room temperature (30 °C). Thus, this study offers the development of low power H 2 sensors with enhanced sensor characteristics, which could be utilized in IoT (Internet of Things) network, with an advantage of facile and scalable fabrication techniques. [ABSTRACT FROM AUTHOR]

• CdTe QDs/MoS 2 NWs hybrid heterostructure thin film have been deposited by sputtering. • NO 2 gas sensing characteristics of CdTe QDs/MoS 2 NWs heterostructure have been studied. • CdTe QDs/MoS 2 NWs heterostructure provides fast response/recovery time for 0.1−10 ppm NO 2 at RT. Molybdenum disulfide (MoS 2) is a very promising candidate for room temperature (RT) gas sensing applications. However, the limitation of synthesis techniques, incomplete recovery, and selectivity at RT are prime drawbacks. In this report, MoS 2 nanoworms (NWs) thin film and CdTe quantum dots (QDs) decorated MoS 2 NWs hybrid heterostructure thin film (CdTe QDs/MoS 2 NWs) have been fabricated by scalable sputtering technique on the p-Si substrate and tested for RT NO 2 gas sensing applications. The proposed CdTe QDs/MoS 2 NWs hybrid heterostructure thin film sensor manifests an excellent sensor response (∼40 %), fast response time = 16 s, complete recovery (recovery time = 114 s) and highly selective towards 10 ppm NO 2 at room temperature in comparison to pristine MoS 2 NWs thin film sensor (response ∼26 %, response/recovery time ∼23 s/incomplete recovery). This superior gas sensing performance may be attributed to the combined effect of factors such as hybrid heteronanostructure with unique morphology, catalytic activity, synergistic effects, and p-n heterojunctions. The approach employed here may lead to the development of RT operable MoS 2 -based heterojunction gas sensors. [ABSTRACT FROM AUTHOR]

Objectives: The coronavirus disease 2019 (COVID-19) outbreak is evolving rapidly worldwide. However, little is known about the association between pregnant women with COVID-19 and its transmission to neonates. This investigation aimed to see if COVID-19 infection could be transmitted vertically into the uterus. Methods: We conducted a prospective observational study. 48 COVID-19 infected mothers were enrolled during their third trimester. A qRT-PCR assay of the nasal and oropharyngeal swab samples was performed to confirm positive for COVID-19 infection as per WHO protocol. In addition, characteristics of pregnant women with confirmed SARS -CoV-2 infection and newborns were documented. Results: Forty-eight expectant mothers, 10 (20.8%) were found symptomatic, and 38 (79.2%) were asymptomatic, with COVID-19 infection were delivered (33 cesarean section & 15 vaginal deliveries). One female child (4.1%) out of 48 newborns was initially diagnosed with COVID-19 infection based on a nucleic acid qRT-PCR. The female child showed no or negligible signs and recovered completely, whereas 47 neonates (95.9%) confirmed negative. None of the mothers or neonates died from COVID-19 related pulmonary problems. Conclusion: There is insufficient evidence on vertical virologic transmission of COVID-19 infection during the third trimester of pregnancy. Additionally, research and surveillance involving adequate testing of samples of placental tissue, breast milk, vaginal swab, amniotic fluid, and cord blood will be needed to establish the possibility of vertical transmission of infection. [ABSTRACT FROM AUTHOR]

Direct growth of atomically thin hierarchal MoS 2 nanoflakes on CVD grown carbon nanotubes has been achieved using magnetron sputtering for electrochemical storage application. This novel technique of preparing MoS 2 @CNT 1D heterostructure using a combination of CVD and PVD proved to be very efficient in structurally engineering the microstructure of electrode material. The super capacitive measurements of the MoS 2 @CNT electrode revealed capacity of 337 mF/cm2 at the sweep rate of 5 mV/s. The storage mechanism involves both electrostatic ionic adsorption as well as Na+ intercalation into the MoS 2 @CNT matrix. Further, using Trassati and Dunn's methods, we found that ionic diffusion and the inner electrode material contributes majorly to the total stored charge. In order to study the phase evolution of electrode material upon several charge-discharge cycles, we employed XPS technique which indicated lower shift in the binding energies of Mo as well as S. This shift indicates partial transition of 2H→1T phase due to the transverse gliding of S plane upon the intercalation of electrolytic ions. The state supercapacitor built using symmetric MoS 2 @CNT electrodes was found to have high areal and volumetric capacitance of 131 mF/cm2 and 2.9 F/cm3 respectively, with high cyclic stability of 97.6% after 2500 cycles. Image 1 [ABSTRACT FROM AUTHOR]

This study presents an innovative approach for targeted drug delivery through the development of Glycyrrhizic acid-loaded zein nanoparticles (GA-LNPs) as a proficient carrier system. The juxtaposition of zein, a hydrophobic biological macromolecule as a protein carrier, and Glycyrrhizic acid (GA), a hydrophilic therapeutic compound, exemplifies the adaptability of hydrocolloids within cutting-edge drug delivery systems. The characterization and functional traits of research encompass multifaceted analyses of natural macromolecules, which elucidate the homogeneous and spherical morphology of GA-LNPs with an average size of 170.49 nm. The controlled drug release profile of GA, orchestrated under simulated gastrointestinal conditions, adheres to diffusion-based Higuchi kinetics, reflecting the controlled release of the natural macromolecules. The intermolecular interactions among Zein, GA, and cross-linker EDC, facilitated through molecular dynamics simulations, fortify the structural integrity of the encapsulation matrix. In Vitro studies revealed enhanced cellular uptake of GA-LNPs in MCF-7 breast cancer cells. This cellular internalization was further confirmed through cytotoxicity assessments using MTT and apoptosis assays (fluorescence microscopy), which demonstrated the prominent anticancer effects of GA-LNPs on MCF-7 in time/dose-dependent manner. The successful formulation of GA-LNPs, coupled with their sustained release and potent anticancer properties, makes them a potential platform for advanced targeted therapeutic strategies in biomedical applications. [Display omitted] • GA-LNPs exhibit superior cellular uptake and promising targeted drug delivery in MCF-7 breast cancer cells. • Exhibit controlled release of GA under gastrointestinal condition indicating its potential as promising drug delivery systems. • GA-LNPs induces cytotoxic effects on MCF-7 cells, promoting apoptosis and inhibiting proliferation. • The study exemplifies the application of natural macromolecules in potent anticancer effects for biomedical advancements. [ABSTRACT FROM AUTHOR]

This study presents an innovative approach for targeted drug delivery through the development of Glycyrrhizic acid-loaded zein nanoparticles (GA-LNPs) as a proficient carrier system. The juxtaposition of zein, a hydrophobic biological macromolecule as a protein carrier, and Glycyrrhizic acid (GA), a hydrophilic therapeutic compound, exemplifies the adaptability of hydrocolloids within cutting-edge drug delivery systems. The characterization and functional traits of research encompass multifaceted analyses of natural macromolecules, which elucidate the homogeneous and spherical morphology of GA-LNPs with an average size of 170.49 nm. The controlled drug release profile of GA, orchestrated under simulated gastrointestinal conditions, adheres to diffusion-based Higuchi kinetics, reflecting the controlled release of the natural macromolecules. The intermolecular interactions among Zein, GA, and cross-linker EDC, facilitated through molecular dynamics simulations, fortify the structural integrity of the encapsulation matrix. In Vitro studies revealed enhanced cellular uptake of GA-LNPs in MCF-7 breast cancer cells. This cellular internalization was further confirmed through cytotoxicity assessments using MTT and apoptosis assays (fluorescence microscopy), which demonstrated the prominent anticancer effects of GA-LNPs on MCF-7 in time/dose-dependent manner. The successful formulation of GA-LNPs, coupled with their sustained release and potent anticancer properties, makes them a potential platform for advanced targeted therapeutic strategies in biomedical applications. [Display omitted] • GA-LNPs exhibit superior cellular uptake and promising targeted drug delivery in MCF-7 breast cancer cells. • Exhibit controlled release of GA under gastrointestinal condition indicating its potential as promising drug delivery systems. • GA-LNPs induces cytotoxic effects on MCF-7 cells, promoting apoptosis and inhibiting proliferation. • The study exemplifies the application of natural macromolecules in potent anticancer effects for biomedical advancements. [ABSTRACT FROM AUTHOR]

Environmental variation has a significant impact on how organisms, including cyanobacteria, respond physiologically and biochemically. Salinity and ultraviolet radiation (UVR)-induced variations in the photopigments of the rice-field cyanobacterium Nostochopsis lobatus HKAR-21 and its photosynthetic performance was studied. We observed that excessive energy dissipation after UVR is mostly caused by Non-Photochemical Quenching (NPQ), whereas photochemical quenching is important for preventing photoinhibition. These findings suggest that ROS production may play an important role in the UVR-induced injury. To reduce ROS-induced oxidative stress, Nostochopsis lobatus HKAR-21 induces the effective antioxidant systems, which includes different antioxidant compounds like carotenoids and enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). The study indicates that Nostochopsis lobatus HKAR-21 exposed to photosynthetically active radiation + UV-A + UV-B (PAB) and PAB + NaCl (PABN) had significantly reduced photosynthetic efficiency. Furthermore, maximum ROS was detected in PAB exposed cyanobacterial cells. The induction of lipid peroxidation (LPO) has been investigated to evaluate the impact of UVR on the cyanobacterial membrane in addition to enzymatic defensive systems. The maximal LPO level was found in PABN treated cells. Based on the findings of this research, it was concluded that salinity and UVR had collegial effects on the major macromolecular components of the rice-field cyanobacterium Nostochopsis lobatus HKAR-21. [ABSTRACT FROM AUTHOR]

Thymic stromal lymphopoietin (TSLP) is a primarily epithelial‐derived cytokine that drives type 2 allergic immune responses. Early life viral respiratory infections elicit high TSLP production, which leads to the development of type 2 inflammation and airway hyperreactivity. The goal of this study was to examine in vivo and in vitro the human airway epithelial responses leading to high TSLP production during viral respiratory infections in early infancy. A total of 129 infants (<1–24 m, median age 10 m) with severe viral respiratory infections were enrolled for in vivo (n = 113), and in vitro studies (n = 16). Infants were classified as ‘high TSLP’ or ‘low TSLP’ for values above or below the 50th percentile. High versus low TSLP groups were compared in terms of type I–III IFN responses and production of chemokines promoting antiviral (CXCL10), neutrophilic (CXCL1, CXCL5, CXCL8), and type 2 responses (CCL11, CCL17, CCL22). Human infant airway epithelial cell (AEC) cultures were used to define the transcriptomic (RNAseq) profile leading to high versus low TSLP responses in vitro in the absence (baseline) or presence (stimulated) of a viral mimic (poly I:C). Infants in the high TSLP group had greater in vivo type III IFN airway production (median type III IFN in high TSLP 183.2 pg/mL vs. 63.4 pg/mL in low TSLP group, p = 0.007) and increased in vitro type I–III IFN AEC responses after stimulation with a viral mimic (poly I:C). At baseline, our RNAseq data showed that infants in the high TSLP group had significant upregulation of IFN signature genes (e.g., IFIT2, IFI6, MX1) and pro‐inflammatory chemokine genes before stimulation. Infants in the high TSLP group also showed a baseline AEC pro‐inflammatory state characterized by increased production of all the chemokines assayed (e.g., CXCL10, CXCL8). High TSLP responses in the human infant airways are associated with pre‐activated airway epithelial IFN antiviral immunity and increased baseline AEC production of pro‐inflammatory chemokines. These findings present a new paradigm underlying the production of TSLP in the human infant airway epithelium following early life viral exposure and shed light on the long‐term impact of viral respiratory illnesses during early infancy and beyond childhood. [ABSTRACT FROM AUTHOR]

In the present work, tuning in optoelectronic properties of sputter deposited zinc oxide (ZnO) thin films on ITO coated glass substrate have been investigated as a function of annealing parameters. Although, the annealing treatment is needed to tune the optoelectronic properties of ZnO layer but it can also modify the electrical properties {a drastic change in sheet resistance (13 Ω/sq. to 23 ohm/sq.) was observed at an annealing temperature of 200 °C} of underlying ITO substrate, which restricted maximum annealing temperature to 200 °C for ZnO at ITO. Vertically standing array of ZnO nano-pipes having single crystal orientation (002) with hexagonal structure, large crystallite size (∼24 nm), lowest lattice strain (0.621%), highest surface roughness (∼16 nm), and lowest R sh (12.3 KΩ/sq.) were obtained for sample annealed at 200 °C for 60 min. The XPS study also revealed that the sample annealed at 200 °C for 60 min contains lowest oxygen related vacancy (23.7), which favors the facile electrons transport when ZnO is used as an electron transport layer (ETL). SE and UV–Vis results revealed best optical parameters i.e., highest transmittance (T ∼ 89%), refractive index (n = 1.98 at 480 nm), and band gap (E g = 3.30 eV), for the sample annealed at 200 °C for 60 min. These results indicated that ZnO nano-pipes based ETL may be a promising candidate for low temperature, high mobility, and cost-effective optoelectronic devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Pd-Pt functionalized nanostructured SiC thin film has been synthesized on porous silicon substrate using RF sputtering. • High resolution XPS spectra of the proposed sensor endorsed excellent stability of ultrathin catalytic layer. • H 2 gas sensing characteristics of Pd-Pt/SiC/PSi electrode is studied in high temperature regime towards low detection limits (5-500 ppm). • Pd-Pt decorated SiC sensor revealed high response with quick response/recovery time for H 2 gas at relatively high temperature. Abstract Present work demonstrates the hydrogen gas (H 2) sensing characteristics of palladium-platinum (Pd-Pt) functionalized silicon carbide (SiC) thin film grown on porous silicon (PSi) substrate for high temperature applications. Nano-crystalline SiC thin film was deposited by RF magnetron sputtering on anodized PSi substrate. The loading of discrete ultra-thin Pd-Pt bimetallic catalytic layer was carefully controlled by varying the sputtering parameters. The proposed device architecture (Pd-Pt/SiC/PSi) revealed significant advantages, such as stable high sensing response, large tunable detection range (5–500 ppm), fast response/recovery time, excellent reproducibility, high selectivity, wide operating temperature regime (25–500 °C) and good durability. The observed high response may be ascribed to the combined effect of enhanced catalytic activity of bimetallic Pd-Pt layer and increased surface area of the proposed sensor. [ABSTRACT FROM AUTHOR]

Ultraviolet radiation (UVR) has been scientifically proven to cause skin disorders such as sunburn, skin cancer and the symptoms of chronic exposure. Natural sun screening compounds have recently gained tremendous attention from the cosmetic and cosmeceutical sectors for treating skin disorders such as hyperpigmentation and aging. A wide range of natural UV-absorbing compounds have been used to replace or reduce the number of synthetic sunscreen molecules. One of the primary causes of photoaging is DNA damage, mainly caused by UVR. Photoprotection provided by traditional sunscreens is purely preventative and has no efficacy after DNA damage has been initiated. As a result, the quest for DNA-repair mechanisms that block, reverse, or postpone pathologic processes in UV-exposed skin has stimulated anti-photoaging research and methods to increase the effectiveness of traditional sunscreens. This review summarizes many natural compounds from microalgae, lichens, and plants that have demonstrated potential photoprotection effects against UV radiation-induced skin damage. Furthermore, it offers an overview of current breakthroughs in DNA-repair enzymes utilized in sunscreens and their influence on photoaging. [ABSTRACT FROM AUTHOR]

Several lines of work have shown that astrocytes release glutamate in response to receptor activation, which results in a modulation of local synaptic activity. Astrocytic glutamate release is Ca2+-dependent and occurs in conjunction with exocytosis of glutamate containing vesicles. However, astrocytes contain a millimolar concentration of cytosolic glutamate and express channels permeable to small anions, such as glutamate. Here, we tested the idea that astrocytes respond to receptor stimulation by dynamic changes in cell volume, resulting in volume-sensitive channel activation, and efflux of cytosolic glutamate. Confocal imaging and whole-cell recordings demonstrated that astrocytes exhibited a transient Ca2+-dependent cell volume increase, which activated glutamate permeable channels. HPLC analysis revealed that glutamate was released in conjunction with other amino acid osmolytes. Our observations indicate that volume-sensitive channel may constitute a previously uncharacterized target for modulation of astrocyte-neuronal interactions. [ABSTRACT FROM AUTHOR]

We describe a simple and versatile scheme to prepare an array of heterofunctional multidentate ligands that permit strong and stable interactions with colloidal semiconductor nanocrystals (quantum dots, QDs) and render them soluble in aqueous environments. These ligands were synthesized by reacting various chain length poly(ethylene glycols) with thioctic acid, followed by ring opening of the dithiolane moiety, creating a bidentate thiol motif with enhanced affinity for CdSe-ZnS core-shell QDs. Functionalization with these ligands permits processability of the nanocrystals not only in aqueous but also in many other polar solvents. These ligands provide a straightforward means of preparing QDs that exhibit greater resistance to environmental changes, making them more amenable for use in live cell imaging and other biotechnological applications. [ABSTRACT FROM AUTHOR]

Aside from myofibers, numerous mononucleated cells reside in the skeletal muscle. These include the mesenchymal cells called fibro-adipogenic progenitors (FAPs), that support muscle development and regeneration in adult muscles. Recent evidence shows that defects in FAP function contributes to chronic muscle diseases and targeting FAPs offers avenues for treating these diseases. [ABSTRACT FROM AUTHOR]

Efficient sarcolemmal repair is required for muscle cell survival, with deficits in this process leading to muscle degeneration. Lack of the sarcolemmal protein dysferlin impairs sarcolemmal repair by reducing secretion of the enzyme acid sphingomyelinase (ASM), and causes limb girdle muscular dystrophy 2B (LGMD2B). The large size of the dysferlin gene poses a challenge for LGMD2B gene therapy efforts aimed at restoring dysferlin expression in skeletal muscle fibers. Here, we present an alternative gene therapy approach targeting reduced ASM secretion, the consequence of dysferlin deficit. We showed that the bulk endocytic ability is compromised in LGMD2B patient cells, which was addressed by extracellularly treating cells with ASM. Expression of secreted human ASM (hASM) using a liver-specific adeno-associated virus (AAV) vector restored membrane repair capacity of patient cells to healthy levels. A single in vivo dose of hASM-AAV in the LGMD2B mouse model restored myofiber repair capacity, enabling efficient recovery of myofibers from focal or lengthening contraction-induced injury. hASM-AAV treatment was safe, attenuated fibro-fatty muscle degeneration, increased myofiber size, and restored muscle strength, similar to dysferlin gene therapy. These findings elucidate the role of ASM in dysferlin-mediated plasma membrane repair and to our knowledge offer the first non-muscle-targeted gene therapy for LGMD2B. [ABSTRACT FROM AUTHOR]

Using total internal reflection fluorescence microscopy, we have developed an assay to monitor individual fusion events between proteoliposomes containing vesicle soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) and a supported planar bilayer containing cognate target SNAREs. Approach, docking, and fusion of individual vesicles to the target membrane were quantified by delivery and subsequent lateral spread of fluorescent phospholipids from the vesicle membrane into the target bilayer. Fusion probability was increased by raising divalent cations (Ca2+ and Mg2+. Fusion of individual vesicles initiated in <100 ms after the rise of Ca2+ and membrane mixing was complete in 300 ms. Removal of the N-terminal Habc domain of syntaxin 1A increased fusion probability >30-fold compared to the full-length protein, but even in the absence of the Habc domain, vesicle fusion was still enhanced in response to Ca2+ increase. Our observations establish that the SNARE core complex is sufficient to fuse two opposing membrane bilayers at a speed commensurate with most membrane fusion processes in cells. This real-time analysis of single vesicle fusion opens the door to mechanistic studies of how SNARE and accessory proteins regulate fusion processes in vivo. [ABSTRACT FROM AUTHOR]