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A series of poly(o-phenylenediamine)/MnCoFe2O4 nanocomposites containing varying concentrations of MnCoFe2O4 were synthesized by in situ oxidative polymerization method. These nanocomposites were characterized by thermal, spectroscopic, microscopic techniques and dielectric properties analyzed at different temperature and frequency. X-ray diffraction and Fourier-transform infrared spectra are confirming the formation of poly(o-phenylenediamine)/MnCoFe2O4 nanocomposites. The Mössbauer spectral data are indicating the inverse nature of MnCoFe2O4 nanoparticles. The ferromagnetic behavior of nanocomposites is ascertained with the hysteresis loops of MnCoFe2O4. Transmission electron microscopy results are giving good evidences for the deposition of MnCoFe2O4 nanoparticles on the poly(o-phenylenediamine) matrix and the modification of spherical morphology of poly(o-phenylenediamine) by MnCoFe2O4. The thermal stability of poly(o-phenylenediamine)/MnCoFe2O4 nanocomposites is increasing with increase in the concentration of MnCoFe2O4 nanoparticles. Dielectric constant and AC conductivity of nanocomposites are varying with applied frequency, temperature and concentration of MnCoFe2O4 nanoparticles. The ethanol gas sensing ability of MnCoFe2O4 has been improved by poly(o-phenylenediamine) matrix. [ABSTRACT FROM AUTHOR]

Poly(o-phenylenediamine) ferrite nanocomposites (PoPD/NiFe2O4) with different ratios of NiFe2O4 nanoparticles (10%, 20% and 30%) were synthesized by in-situ chemical oxidative polymerization method. NiFe2O4 nanoparticles were prepared by auto-combustion method using urea as fuel. The PoPD/NiFe2O4 nanocomposites were characterized by FTIR and XRD, SEM, TEM and thermogravimetric analysis. The FTIR and XRD pattern ascertain the interaction of PoPD with NiFe2O4 nanoparticles. The spherical morphology of PoPD is affected by the incorporation of NiFe2O4 nanoparticles. Magnetic properties of PoPD/NiFe2O4 nanocomposites were analyzed by using vibrating sample magnetometer. The hysteresis loops of NiFe2O4 and PoPD/NiFe2O4 nanocomposites exhibited ferromagnetic nature at room temperature. Dielectric properties of PoPD/NiFe2O4 nanocomposites at different temperatures have been carried in the frequency range from 50 Hz to 5 MHz. The ethanol gas sensing property of PoPD/NiFe2O4 nanocomposites was studied at room temperature using PMMA fiber optic method. [ABSTRACT FROM AUTHOR]

Abstract: We have successfully synthesized Co doped SnO2 nanoparticles by a simple microwave irradiation technique. Powder X-ray diffraction results reveal that the SnO2 doped with cobalt concentration from 0 to 5 wt % crystallizes in tetragonal rutile-type structure. The products were annealed at 600 °C for 5 h in ambient atmosphere in order to improve crystallinity and structural perfection. Transmission electron microscopy (TEM) studies illustrate that both the undoped and Co doped SnO2 crystallites form in spherical shapes with an average diameter of 30–15 nm, which is in good agreement with the average crystallite sizes calculated by Scherrer's formula. A considerable red shift in the absorbing band edge was observed with increasing of Co content (0–5 wt %) by using UV–Vis diffuse reflectance spectroscopy (DRS). Oxygen-vacancies, tin interstitial and structural defects were analyzed using photoluminescence (PL) spectroscopy. Electron paramagnetic resonance (EPR) spectroscopic studies clearly showed that the Co2+ was incorporated into the SnO2 host lattice. Ethanol gas sensitivity of pure and Co-doped (5 wt %) SnO2 nanoparticles were experimented at ambient temperature using optical fiber based on clad-modified method. By modifying the clad exposure to ethanol vapor, the sensitivities were estimated to be 18 and 30 counts/100 ppm for undoped and Co-doped SnO2 nanoparticles, respectively. These results show that the Co doping into SnO2 enhances its ethanol gas sensitivity significantly. [Copyright &y& Elsevier]

(MnNi)Fe2O4 nanoparticle was prepared by auto-combustion method and its composites with poly(o-phenylenediamine) (PoPD) were synthesized through in-situ oxidative polymerization method. FTIR and XRD studies confirmed the formation of PoPD/(MnNi)Fe2O4 nanocomposites. The crystalline size of PM1, PM2 and PM3 are 44 nm, 45 nm and 16 nm respectively. The dispersion of (MnNi)Fe2O4 nanoparticles in PoPD reduces their crystalline size. In PoPD/(MnNi)Fe2O4 nanocomposites, spherical morphology of PoPD is modified by (MnNi)Fe2O4 nanoparticles. TEM images showed that (MnNi)Fe2O4 nanoparticles are dispersed in PoPD matrix. The hysteresis loops of (MnNi)Fe2O4 nanoparticles and PoPD/(MnNi)Fe2O4 nanocomposites indicated that they are ferrimagnetic in nature. The saturation magnetization value of (MnNi)Fe2O4, PM1, PM2 and PM3 are 29.871 emu/g, 3.342 emu/g, 4.298 emu/g and 7.877 emu/g respectively. The thermal stability and saturation magnetization value of PoPD/(MnNi)Fe2O4 nanocomposites increases with increase in concentration of (MnNi)Fe2O4 nanoparticles. Dielectric properties of PoPD/(MnNi)Fe2O4 nanocomposites were studied at different frequencies and temperature. The Mn2+ substitution in NiFe2O4 has improved the ethanol sensitivity of PoPD/(MnNi)Fe2O4 nanocomposites. The dielectric constant of PoPD/(MnNi)Fe2O4 nanocomposites increases with increase in frequency, temperature and concentration of nanoparticles. Theoretical investigations of the metal oxide complex were done by utilizing a DFT/ B3LYP/LANL2DZ basis set. The optimized bond parameters (bond lengths, bond angles and dihedral angles) were determined using identical level of basis set. The NLO properties of the title compound was calculated using first-order hyperpolarizability calculation. The HOMO-LUMO, which clarifies the possible charge transfer, happens inside the molecule. [ABSTRACT FROM AUTHOR]

A novel one-pot microwave irradiation method has been adapted to synthesize cubic spinel cobalt oxide/multi-walled carbon nanotube composite. X-ray diffraction and scanning electron microscope results reveal that cubic spinel structure of Co3O4 with nanodimensional and well implanted over the multi walled carbon nanotubes (MWCNTs) metrics. The N2 adsorption–desorption results exhibit that Co3O4/MWCNT composite confirms the highest specific area (135 m2 g−1) and lower pore size 7.8 nm compared with pure Co3O4 (surface area 88 = m2 g−1 and pore size = 10.5 nm). The XPS result demonstrates that Co is 2+ in state in the spinel Co3O4. The gas-detecting test displayed that Co3O4/MWCNT composite indicated high sensitivity toward ethanol (35 counts/ppm) and ammonia (51 counts/ppm) gases as compared with pure Co3O4 (24 counts/ppm and 43 counts/ppm for ethanol and ammonia gases, respectively). It also exhibits excellent long-term stability with small deviations (less than 5%) for the evaluation of a 2-month period. The enhanced gas-sensing mechanism of Co3O4/MWCNT was also discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract: Ethanol sensitivities of SnO2 and SnO2:CuO nanoparticles are studied using a clad-modified fiber-optic sensor. The sensing materials (SnO2 and SnO2:CuO) are structurally characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscope (HRTEM) and their crystallite sizes are found to be 10 and 8–20nm, respectively. The refractive indices of the sensing materials ( and ) found from UV–vis analysis show that the fiber-optic sensor works under leaky mode operation. SnO2:CuO exhibits higher ethanol sensitivity compared to pure SnO2. It is found that the addition of CuO into SnO2 allows the effective formation of more number of oxygen vacancies, heterojunction, and high crystalline nanoparticles, which enhance its sensitivity to about three times than that of pure SnO2. [Copyright &y& Elsevier]

Single-particle tracking demonstrates that individual filaments in bundles of vimentin intermediate filaments are transported in the cytoplasm by motor proteins along microtubules. Furthermore, using 3D FIB-SEM the authors showed that vimentin filament bundles are loosely packed and coaligned with microtubules. Vimentin intermediate filaments (VIFs) form complex, tight-packed networks; due to this density, traditional ensemble labeling and imaging approaches cannot accurately discern single filament behavior. To address this, we introduce a sparse vimentin-SunTag labeling strategy to unambiguously visualize individual filament dynamics. This technique confirmed known long-range dynein and kinesin transport of peripheral VIFs and uncovered extensive bidirectional VIF motion within the perinuclear vimentin network, a region we had thought too densely bundled to permit such motility. To examine the nanoscale organization of perinuclear vimentin, we acquired high-resolution electron microscopy volumes of a vitreously frozen cell and reconstructed VIFs and microtubules within a ~50 μm 3 window. Of 583 VIFs identified, most were integrated into long, semi-coherent bundles that fluctuated in width and filament packing density. Unexpectedly, VIFs displayed minimal local co-alignment with microtubules, save for sporadic cross-over sites that we predict facilitate cytoskeletal crosstalk. Overall, this work demonstrates single VIF dynamics and organization in the cellular milieu for the first time., Competing Interests: Statements and Declarations All authors declare no conflict of interest.

Gigaxonin is an adaptor protein for E3 ubiquitin ligase substrates. It is necessary for ubiquitination and degradation of intermediate filament (IF) proteins. Giant axonal neuropathy is a pathological condition caused by mutations in the GAN gene that encodes gigaxonin. This condition is characterized by abnormal accumulation of IFs in both neuronal and non-neuronal cells; however, it is unclear what causes IF aggregation. In this work, we studied the dynamics of IFs using their subunits tagged with a photoconvertible protein mEOS 3.2. We have demonstrated that the loss of gigaxonin dramatically inhibited transport of IFs along microtubules by the microtubule motor kinesin-1. This inhibition was specific for IFs, as other kinesin-1 cargoes, with the exception of mitochondria, were transported normally. Abnormal distribution of IFs in the cytoplasm can be rescued by direct binding of kinesin-1 to IFs, demonstrating that transport inhibition is the primary cause for the abnormal IF distribution. Another effect of gigaxonin loss was a more than 20-fold increase in the amount of soluble vimentin oligomers in the cytosol of gigaxonin knock-out cells. We speculate that these oligomers saturate a yet unidentified adapter that is required for kinesin-1 binding to IFs, which might inhibit IF transport along microtubules causing their abnormal accumulation., (© 2023 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Expansin, a cell wall-modifying gene family, has been well characterized and its role in biotic and abiotic stress resistance has been proven in many monocots, but not yet studied in banana, a unique model crop. Banana is one of the staple food crops in developing countries and its production is highly influenced by various biotic and abiotic factors. Characterizing the expansin genes of the ancestor genome ( M. acuminata and M. balbisiana ) of present day cultivated banana will enlighten their role in growth and development, and stress responses. In the present study, 58 (MaEXPs) and 55 (MbaEXPs) putative expansin genes were identified in A and B genome, respectively, and were grouped in four subfamilies based on phylogenetic analysis. Gene structure and its duplications revealed that EXPA genes are highly conserved and are under negative selection whereas the presence of more number of introns in other subfamilies revealed that they are diversifying. Expression profiling of expansin genes showed a distinct expression pattern for biotic and abiotic stress conditions. This study revealed that among the expansin subfamilies, EXPAs contributed significantly towards stress-resistant mechanism. The differential expression of MaEXPA18 and MaEXPA26 under drought stress conditions in the contrasting cultivar suggested their role in drought-tolerant mechanism. Most of the MaEXPA genes are differentially expressed in the root lesion nematode contrasting cultivars which speculated that this expansin subfamily might be the susceptible factor. The downregulation of MaEXPLA6 in resistant cultivar during Sigatoka leaf spot infection suggested that by suppressing this gene, resistance may be enhanced in susceptible cultivar. Further, in-depth studies of these genes will lead to gain insight into their role in various stress conditions in banana., Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-021-03106-x., Competing Interests: Conflict of interestThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© King Abdulaziz City for Science and Technology 2022.)

A Disintegrin and Metalloproteinase with ThromboSpondin motif (ADAMTS) 5 functions as an anti-angiogenic and anti-cancer protein independent of its metalloproteinase activity. Both full-length ADAMTS5 and TS5-p45, the autocatalytically cleaved C-terminal 45 kDa truncate of ADAMTS5, inhibits angiogenesis, and induces endothelial cell (EC) apoptosis. However, how ADAMTS5 triggers EC apoptosis remains unclear. This work shows that caspase-8 (Cas-8) and caspase-9 (Cas-9) are involved in TS5-p45-induced EC apoptosis. We identify cell surface nucleolin (NCL) as a novel high-affinity receptor for TS5-p45 in ECs, mediating TS5-p45's cell surface binding and pro-apoptotic function. We show that the central RNA-binding domain (RBD) of NCL is essential and sufficient for its binding to TS5-p45. Upon interacting with EC surface NCL, TS5-p45 is internalized through clathrin- and caveolin-dependent endocytosis and trafficked to the nucleus via late endosomes (LEs). We demonstrate that the nuclear trafficking of TS5-p45 is important for its pro-apoptotic activity as disruption of LE membrane integrity with an endosomolytic peptide suppressed both nuclear trafficking and pro-apoptotic activity of TS5-p45. Through cell surface biotinylation, we revealed that cell surface NCL shuttles extracellular TS5-p45 to the nucleus to mediate apoptosis. Furthermore, blocking the importin α1/ß1 receptor hindered the nuclear trafficking of TS5-p45, suggesting the involvement of the nuclear importing machinery for this nuclear translocation. RNA-seq identified many apoptosis-related genes that are differentially expressed at least two-fold in TS5-p45-treated ECs, with 10 of them qRT-PCR-validated and at least 5 of these genes potentially contributing to TS5-p45-NCL-induced apoptosis. Altogether, our work identifies NCL as a novel cell surface receptor for ADAMTS5 and demonstrates the critical role of NCL-mediated internalization and nuclear trafficking for ADAMTS5-induced EC apoptosis. These findings reveal novel mechanistic insights of the secreted metalloproteinase ADAMTS5 in angiogenesis inhibition., (© 2022. The Author(s).)

Purpose: Hospital-acquired pressure ulcers are a significant cause of morbidity and consume considerable financial resources. Turn protocols (repositioning patients at regular intervals) are utilized to reduce incidence of pressure ulcers. Adherence to turn protocols is particularly challenging for nursing teams, given the high number of interventions in intensive care unit, and lack of widely available tools to monitor patient position and generate alerts. We decided to develop and evaluate usefulness of a continuous patient position monitoring system to assist nurses in improving turn protocol compliance., Methods: We conducted a prospective, non-randomized, multiphase, multicentre trial. In Phase I (control group), the function of the device was not revealed to nurses so as to observe their baseline adherence to turn protocol, while Phase II (intervention group) used continuous patient position monitoring system to generate alerts, when non-compliant with the turn protocol. All consecutive patients admitted to one of the two intensive care units during the study period were screened for enrolment. Patients at risk of acquiring pressure ulcers (Braden score < 18) were considered for the study (Phase I (N = 22), Phase II (N = 25))., Results: We analysed over 1450 h of patient position data collected from 40 patients (Phase I (N = 20), Phase II (N = 20)). Turn protocol compliance was significantly higher in Phase II (80.15 ± 8.97%) compared to the Phase I (24.36 ± 12.67%); p  < 0.001., Conclusion: Using a continuous patient position monitoring system to provide alerts significantly improved compliance with hospital turn protocol. Nurses found the system to be useful in providing automated turn reminders and prioritising tasks., (© The Intensive Care Society 2018.)

Inhibiting tumor angiogenesis is a well-established approach for anticancer therapeutic development. A Disintegrin-like and Metalloproteinase with ThromboSpondin Motifs 5 (ADAMTS5) is a secreted matrix metalloproteinase in the ADAMTS family that also functions as an anti-angiogenic/anti-tumorigenic molecule. Its anti-angiogenic/anti-tumorigenic function is independent from its proteinase activity, but requires its first thrombospondin type 1 repeat (TSR1). However, it is not known if recombinant TSR1 (rTSR1) can function as an anticancer therapeutic. In this report, we expressed and purified a 75-residue recombinant TSR1 polypeptide from E. coli and investigated its ability to function as an anticancer therapeutic in mice. We demonstrate that rTSR1 is present in the blood circulation as well as in the tumor tissue at 15 min post intraperitoneal injection. Intraperitoneal delivery of rTSR1 potently suppressed subcutaneous B16F10 melanoma growth as a single agent, accompanied by diminished tumor angiogenesis, increased apoptosis, and reduced cell proliferation in the tumor tissue. Consistently, rTSR1 dose-dependently induced the apoptosis of cultured human umbilical vein endothelial cells (HUVECs) in a caspase-dependent manner. This work indicates that rTSR1 of ADAMTS5 can function as a potent anticancer therapy in mice. It thus has the potential to be further developed into an anticancer drug.

Hospital acquired pressure ulcers (HAPUs) is a major problem that affects around one in twenty patients who are admitted in hospital with sudden illness. These ulcers often occur when patients have limited mobility and cannot change positions in bed on their own. Traditionally, the occurrence of HAPUs has been minimized by turning the patient every 2 hours to alternating lateral and supine positions, and by using pressure redistributing mattresses. In many healthcare facilities, such a patient repositioning schedule is not always maintained owing to low caregiver compliance to turning protocols. Difficulty in monitoring patient position continuously, lack of turn reminders/alerts and suboptimal caregiver staffing ratio increases the occurrence of HAPUs. A novel method to address the need for improved pressure ulcer prevention is presented. The proposed method consists of a wearable device which continuously monitors the patient's position and communicates wirelessly with a tablet which enables alerts to be sent to the caregiver when a patient turn is due in accordance with the protocol adopted by the hospital. The patient's position is continuously monitored and the turning procedure carried out is logged and updated on the hospital's cloud system, thereby enabling centralized monitoring. Under a controlled setting, system was able to continuously monitor patient's position and can accurately detect standard patient positions.

Despite the rigorous research on abnormal angiogenesis, there is a persistent need for the development of new and efficient therapies against angiogenesis-related diseases. The role of Lysyl oxidase (LOX) in angiogenesis and cancer has been established in prior studies. Copper is known to induce the synthesis of LOX, and hence regulates its activity. Hypoxia-induced metastasis is dependent on LOX expression and activity. It has been believed that the inhibition of LOX would be a therapeutic strategy to inhibit angiogenesis. To explore this, we designed peptides (M peptides) from the copper-binding region of LOX and hypothesized them to modulate LOX. The peptides were characterized, and their copper-binding ability was confirmed by mass spectrometry. The M peptides were found to reduce the levels of intracellular copper when the cells were co-treated with copper. The peptides showed promising effect on aortic LOX, recombinant human LOX and LOX produced by human umbilical vein endothelial cells (HUVECs). The study also explores the effect of these peptides on copper and hypoxia-stimulated angiogenic response in HUVECs. It was found that the M peptides inhibited copper/hypoxia-induced LOX activity and inhibited stimulated HUVEC tube formation and migration. This clearly indicated the potential of M peptides in inhibiting angiogenesis, highlighting their role in the formulation of drugs for the same., (Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.)