Search

Mnx Zr1-x O2 (MnZO) thin films were grown by pulsed-laser deposition on single crystalline yttria-stabilized zirconia (YSZ) and a-plane sapphire substrates with manganese contents from 0 up to about 50 at.%. A fully stabilized cubic structure occurs for Mn contents x equal or larger than 20 at. % on YSZ substrates. For x ≈0.5, phase separation of Mn-oxides occurs. Below 11 at. %, only the monoclinic phase is observed. The thin films are electrically insulating up to x = 0.3. By further increasing the Mn content or by reducing the structural quality, the resistivity ρ decreases from 3×109Ωcm down to 3×104Ωcm. For MnZO thin films on a-plane sapphire substrates, Seebeck-effect measurements verify a transition from p-type conductivity to n-type conductivity around 500 K with increasing temperature, which is probably governed by an enhanced ionic conduction. Cathodoluminescence measurements clearly show a Mn-related emission at about 2.8 eV, correlated to an Mn-induced electronic state in the bandgap of MnZO. From electron paramagnetic resonance measurements and x ray photoelectron spectroscopy, we conclude that both Mn3+ and Mn4+ is present in our MnZO thin films. [ABSTRACT FROM AUTHOR]

We report on luminescence properties from T=2 K up to room temperature of ZnO/Zn1-xCdxO/ZnO double heterostructures grown by pulsed-laser deposition on a-plane sapphire substrates. Depending on the growth conditions, the spectral position of the Zn1-xCdxO related maximum has been tuned from 3.19 to 3.056 eV, corresponding approximately to Cd contents between 2.1% and 5.6%. Independent of x we observe intense phonon replicas of the photoluminescence (PL) maximum. The quenching of the luminescence intensity indicates the presence of two thermal activation energies, one of them being assigned to the delocalization of excitons from donors. The temperature-dependent PL spectra exhibit the so-called "S-shape" behavior as function of temperature for the Zn1-xCdxO due to the superposition of the usual S-shape, caused by the alloy, and a change in the peak character from donor-bound exciton to free exciton. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the different luminescence properties of ZnO/[Zn.sub.1-x][Cd.sub.x]O/ZnO double heterostructures. The photoluminescence spectra of the heterostructures are shown to be completely dependent on the temperature.

Abstract: Arabinogalactan protein JC from Jatropha curcas seed endosperm (mean molecular weight 140kDa) was isolated by cold water extraction and characterized concerning sugar and amino acid composition. At 10 and 100µg/mL JC stimulated mitochondrial activity (MTT test) of human skin cells (HaCaT keratinocytes, fibroblasts) and the ATP status of primary keratinocytes. JC did not influence the cellular proliferation, while primary keratinocytes were triggered into differentiation status. Investigations on a potential mode of action of JC were performed on complex organotypic skin equivalents. JC induced the production of HGF, KGF and TGFβ, with TGFβ being the main inductor for the differentiation-inducing effect of JC. Also the expression of GM-CSF was stimulated strongly by JC. This in vitro activity profile indicated JC to be a potent inductor of cellular differentiation via stimulation of growth hormones and TGF-β-induced cell signaling. [ABSTRACT FROM AUTHOR]

ZnO/CdxZn1-xO double heterostructures grown on a-plane sapphire substrates by pulsed-laser deposition were investigated concerning their photoluminescence properties. The localization of excitons in the CdxZn1-xO alloys were studied and analyzed with temperature dependent photoluminescence measurements from T=2 K up to room temperature. The temperature dependence of the Huang-Rhys factor was used to calculate the fraction of strongly localized excitons for this temperature range. The depth of the localization potentials is estimated using two different methods. [ABSTRACT FROM AUTHOR]

Background and Purpose: Individuals with attention deficit/hyperactivity disorder (ADHD) experience a variety of challenges in daily life and equine-assisted therapies (EATs) have grown in popularity for children with ADHD. This review aims to examine the effectiveness of EATs on behavioural, psychological and physical symptoms in the treatment of children with ADHD., Materials and Methods: A systematic search of databases (Cochrane Library, Embase, Emcare, ERIC, MEDLINE, OTseeker, ProQuest, PsycINFO and Scopus) was conducted in February 2019. Methodological quality of the studies was assessed using a modified McMaster critical appraisal tool., Results: Ten studies met the inclusion criteria and overall, positive trends were identified in behavioural, psychological and physical outcome measures following the participation in an EAT. However, due to methodological constraints, caution is required when interpreting these findings., Conclusion: While EAT may offer some positive benefits for children with ADHD, further methodologically robust research is required before definitive recommendations can be made., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Aims: Aqueous extracts from the roots of Althea officinalis L. (Malvaceae) are widely used for treatment of irritated mucosa. The clinical proven effects are related to the presence of bioadhesive and mucilaginous polysaccharides from the rhamnogalacturonan type, leading to the physical formation of mucin-like on top of the irritated tissues. No data are available if the extracts or the polysaccharides from these extract exert an active influence on mucosal or connective tissue cells, in order to initiated changes in cell physiology, useful for better tissue regeneration., Methodology: In vitro investigations of aqueous A. officinalis extract AE and raw polysaccharides (RPS) on epithelial KB cells and primary dermal human fibroblasts (pNHF) using WST1 vitality test and BrdU proliferation ELISA. Gene expression analysis by microarray from KB cells. Internalisation studies of polysaccharides were performed by laser scanning microscopy., Results: AE (1, 10 microg/mL) had stimulating effect on cell viability and proliferation of epithelial KB cells. RPS (1, 10 microg/mL) stimulated cell vitality of epithelial cells significantly without triggering the cells into higher proliferation status. Neither AE nor RPS had any effect on fibroblasts. FITC-labeled RPS was shown to be internalised into epithelial cells, but not into fibroblasts. FITC-RPS was shown to form bioadhesive layers on the cell surface of dermal fibroblasts. Microarray analysis indicated an up-regulation of genes related to cell adhesion proteins, growth regulators, extracellular matrix, cytokine release and apoptosis., Conclusion: Aqueous extracts and polysaccharides from the roots of A. officinalis are effective stimulators of cell physiology of epithelial cells which can prove the traditional use of Marshmallow preparations for treatment of irritated mucous membranes within tissue regeneration., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)

Ethnopharmacological Relevance: Aqueous extracts from the bark of Mimosa tenuiflora (Willd.) Poirett (Mimosaceae), tradionally known as "tepescohuite", are widely used for wound-healing and burns in middle and South America. No pharmacological data are available on the influence of aqueous extracts and high molecular constituents on human skin cells., Materials and Methods: Tests were performed on human primary dermal fibroblasts and human HaCaT keratinocytes by quantification of mitochondrial activity (MTT, WST-1), proliferation (BrdU incorporation), necrosis (LDH) and gene expression profiling (RT-PCR)., Results: Water extract WE (10 and 100 microg/mL) expressed loss of cell viability and proliferation in dermal fibroblasts. Ethanol-precipitated compounds EPC (10 microg/mL), isolated from WE significantly stimulated mitochondrial activity and proliferation of dermal fibroblasts. Minor stimulation of human kerationocytes by EPC was found only at 100 microg/mL level. The differentiation behavior of keratinocytes was not influenced by EPC. EPC had no influence on the expression of specific proliferation and differentiation related genes so that the mode of action remains unclear. By bioactivity-guided fractionation two arabinogalactan-enriched fractions (F2, F3) were isolated from EPC and identified as the stimulating principles of EPC against fibroblasts., Conclusions: A significant in vitro stimulation of dermal fibroblast activity and proliferation by arabinogalactans from Mimosa tenuiflora provides a rational for the traditional use of the bark material for wound healing.

An arabinogalactan protein (F2) was isolated in 1.5% yield from the seeds of Ribes nigrum L. (Grossulariaceae) by aqueous extraction and a one-step anion exchange chromatography on DEAE-Sephacel with 24% galactose, 43% arabinose, and 20% xylose as main carbohydrate residues. Methylation analysis revealed the presence of a 1,3-/1,3,6-galactose backbone, side chains from arabinose in different linkages, and terminal xylose residues. The polysaccharide which turned out to be an arabinogalactan protein had a molecular weight of >10(6) Da and deaggregated under chaotropic conditions. The cellular dehydrogenase activities (MTT and WST-1 tests) of human skin cells (fibroblasts, keratinocytes) as well as the proliferation rate of keratinocytes (BrdU incorporation ELISA) were significantly stimulated by the polymer at 10 and 100 microg/mL. F2 had no influence on differentiation status of keratinocytes and did not exhibit any cytotoxic potential (LDH test). The biological activity of F2 was not dependent on the high molecular weight. Influence of the polysaccharide on the gene expression of specific growth factors, growth factor receptors, signal proteins and marker proteins for skin cell proliferation, and differentiation by RT-PCR could not be shown. Gene array investigations indicated an increased expression of various genes encoding for catabolic enzymes, DNA repair, extracellular matrix proteins, and signal transduction factors. Removal of terminal arabinose residues by alpha-L-arabinofuranosidase did not influence the activity toward skin cells, while the treatment with beta-D-galactosidase yielded an inactive polysaccharide. The FITC-labeled polysaccharide was incorporated in a time-dependent manner into human fibroblasts (laser scanning microscopy) via endosomal transport. This internalization of the polysaccharide was inhibited by Cytochalasin B.

The authors discuss the indication and various methods of repair of the rotator cuff tear. The results in 24 patients are evaluated with respect to postoperative pain and function.

The elbow-prosthesis, design St. George, a hinge prosthesis is developed according to the principle of the Low Friction Arthroplasty. Only small resection of the joint is necessary so that in the "second line of defence" a resection-arthroplasty of elbow is possible. The experiences on 44 implanted prosthesis and the results of 37 cases are described. Restriction of motion, pain, instability and ankylosis in case of rheumatiod arthritis and posttraumatic arthrosis were the main indications.