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This study presents a set of vibrational characterizations on a nanogel-cross-linked porous freeze-dried gel (NanoCliP-FD gel) scaffold for tissue engineering and regenerative therapy. This scaffold is designed for the in vitro culture of high-quality cartilage tissue to be then transplanted in vivo to enable recovery from congenital malformations in the maxillofacial area or crippling jaw disease. The three-dimensional scaffold for in-plate culture is designed with interface chemistry capable of stimulating cartilage formation and maintaining its structure through counteracting the dedifferentiation of mesenchymal stem cells (MSCs) during the formation of cartilage tissue. The developed interface chemistry enabled high efficiency in both growth rate and tissue quality, thus satisfying the requirements of large volumes, high matrix quality, and superior mechanical properties needed in cartilage transplants. We characterized the cartilage tissue in vitro grown on a NanoCliP-FD gel scaffold by human periodontal ligament-derived stem cells (a type of MSC) with cartilage grown by the same cells and under the same conditions on a conventional (porous) atelocollagen scaffold. The cartilage tissues produced by the MSCs on different scaffolds were comparatively evaluated by immunohistochemical and spectroscopic analyses. Cartilage differentiation occurred at a higher rate when MSCs were cultured on the NanoCliP-FD gel scaffold compared to the atelocollagen scaffold, and produced a tissue richer in cartilage matrix. In situ spectroscopic analyses revealed the cell/scaffold interactive mechanisms by which the NanoCliP-FD gel scaffold stimulated such increased efficiency in cartilage matrix formation. In addition to demonstrating the high potential of human periodontal ligament-derived stem cell cultures on NanoCliP-FD gel scaffolds in regenerative cartilage therapy, the present study also highlights the novelty of Raman spectroscopy as a non-destructive method for the concurrent evaluation of matrix quality and cell metabolic response. In situ Raman analyses on living cells unveiled for the first time the underlying physiological mechanisms behind such improved chondrocyte performance. [ABSTRACT FROM AUTHOR]

High-energy (MeV) implantation of Al[sup +] or B[sup +] into 4H-SiC epilayers has been investigated. A 3 µm deep pn junction was formed by multiple-step Al[sup +] or B[sup +] implantation with implantation energies up to 6.2 or 3.4 MeV, respectively. Rutherford backscattering channeling and cross-sectional transmission electron microscopy analyses have revealed residual damages in the implanted layers even after high-temperature annealing at 1600-1800 °C. Nevertheless, high electrical activation ratios over 90% have been achieved for both Al[sup +] - and B[sup +]-implanted layers by annealing at 1800 °C. Mesa pin diodes with a 15-µm-thick i layer formed by MeV implantation have exhibited high breakdown voltages of 2860-3080 V. The reverse characteristics of diodes have been substantially improved by increasing annealing temperature up to 1800 °C. The diode performance is discussed with the results of deep level analyses near the junctions. [ABSTRACT FROM AUTHOR]

Fracture of the humeral medial epicondyle is a relatively common injury in children. Surgery is a good option for treatment, but correct diagnosis is important. Most fractures occur after the ossification of the medial epicondylar apophysis. If a fracture occurs before the ossification of the medial epicondyle, it is undetectable by radiographs. Here we report a case of an unossified medial epicondyle fracture of the humerus. A 9-year-old boy had persistent pain in the medial side of the right elbow after a fall. Despite his pain, he could move his injured elbow with a range from 60 to 90°. Radiographs and computed tomography showed neither fracture nor dislocation in the injured elbow, and soft tissue swelling was the only finding. Neither the trochlea nor the medial epicondyle was ossified. Magnetic resonance imaging showed that the medial epicondyle was separated from the medial metaphysis and displaced. This clear finding led us to surgical fixation. Under general anesthesia, valgus stress showed gross instability of the injured elbow. Two years after the operation, he had no complaints and could play sports with the same range of motion as the left elbow. It is important to keep in mind that medial epicondylar fractures may be hidden in a normal radiograph before the ossification of the medial epicondylar apophysis. [ABSTRACT FROM AUTHOR]

Ulnar nerve neuropathy is a rare complication following the carpal tunnel release. Above all, compression neuropathy is much rare. We report an acute ulnar nerve neuropathy following open carpal tunnel release due to the volar and ulnar displacement of the flexor tendons from the carpal tunnel and review the literature. [ABSTRACT FROM AUTHOR]

Characteristics of p-n junction fabricated by aluminum-ion (Al[sup +] or boron-ion (B[sup +]) implantation and high-dose Al[sup +]-implantation into 4H-SiC (0001) have been investigated. By the combination of high-dose (4 × 10[sup 15] cm[sup -2]) Al[sup +] implantation at 500 °C and subsequent annealing at 1700 °C, a minimum sheet resistance of 3.6 kΩ/... (p-type) has been obtained. Three types of diodes with planar structure were fabricated by employing Al[sup +] or B[sup +] implantation. B[sup +]-implanted diodes have shown higher breakdown voltages than Al[sup +]-implanted diodes. A SiC p-n diode fabricated by deep B[sup +] implantation has exhibited a high breakdown voltage of 2900 V with a low on-resistance of 8.0 mΩcm² at room temperature. The diodes fabricated in this study showed positive temperature coefficients of breakdown voltage, meaning avalanche breakdown. The avalanche breakdown is discussed with observation of luminescence. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the effects of surface defects on the performance of 4H- and 6H-silicon carbide p-n junction diodes. Diode fabrication; Results and discussion; Conclusions.

Tooth loss impairs mastication, deglutition and esthetics and affects systemic health through nutritional deficiency, weight loss, muscle weakness, delayed wound healing, and bone fragility. Approximately 90% of tooth loss is due to dental caries and periodontal disease. Accordingly, early treatment of dental caries is essential to maintaining quality of life. To date, the clinical diagnosis of dental caries has been based on each dentist's subjective assessment, but this visual method lacks objectivity. To improve diagnostic ability, highly sensitive quantitative methods have been developed for the diagnosis and prevention of dental caries and are gradually becoming a mandatory item in modern dentistry. High-resolution Raman spectroscopy is a suitable tool for recognizing the subtle structural changes that occur in dental enamel in already developed or, more importantly, incipient dental caries. Raman analysis could soon emerge as a breakthrough in dentistry because of its high diagnostic sensitivity. In this study, we build upon our previous findings in a new analysis of dental caries using Raman spectroscopy imaging and discuss the possibility of using Raman photonic imaging in support of objective diagnostics in dentistry. Our findings support the Raman method of caries detection in comparison with other conventional or new approaches. [ABSTRACT FROM AUTHOR]

This study targets on-site/real-time taxonomic identification and metabolic profiling of seven different Candida auris clades/subclades by means of Raman spectroscopy and imaging. Representative Raman spectra from different Candida auris samples were systematically deconvoluted by means of a customized machine-learning algorithm linked to a Raman database in order to decode structural differences at the molecular scale. Raman analyses of metabolites revealed clear differences in cell walls and membrane structure among clades/subclades. Such differences are key in maintaining the integrity and physical strength of the cell walls in the dynamic response to external stress and drugs. It was found that Candida cells use the glucan structure of the extracellular matrix, the degree of α-chitin crystallinity, and the concentration of hydrogen bonds between its antiparallel chains to tailor cell walls' flexibility. Besides being an effective ploy in survivorship by providing stiff shields in the α–1,3–glucan polymorph, the α–1,3–glycosidic linkages are also water-insoluble, thus forming a rigid and hydrophobic scaffold surrounded by a matrix of pliable and hydrated β–glucans. Raman analysis revealed a variety of strategies by different clades to balance stiffness, hydrophobicity, and impermeability in their cell walls. The selected strategies lead to differences in resistance toward specific environmental stresses of cationic/osmotic, oxidative, and nitrosative origins. A statistical validation based on principal component analysis was found only partially capable of distinguishing among Raman spectra of clades and subclades. Raman barcoding based on an algorithm converting spectrally deconvoluted Raman sub-bands into barcodes allowed for circumventing any speciation deficiency. Empowered by barcoding bioinformatics, Raman analyses, which are fast and require no sample preparation, allow on-site speciation and real-time selection of appropriate treatments. [ABSTRACT FROM AUTHOR]

Oral candidiasis, a common opportunistic infection of the oral cavity, is mainly caused by the following four Candida species (in decreasing incidence rate): Candida albicans, Candida glabrata, Candida tropicalis, and Candida krusei. This study offers in-depth Raman spectroscopy analyses of these species and proposes procedures for an accurate and rapid identification of oral yeast species. We first obtained average spectra for different Candida species and systematically analyzed them in order to decode structural differences among species at the molecular scale. Then, we searched for a statistical validation through a chemometric method based on principal component analysis (PCA). This method was found only partially capable to mechanistically distinguish among Candida species. We thus proposed a new Raman barcoding approach based on an algorithm that converts spectrally deconvoluted Raman sub-bands into barcodes. Barcode-assisted Raman analyses could enable on-site identification in nearly real-time, thus implementing preventive oral control, enabling prompt selection of the most effective drug, and increasing the probability to interrupt disease transmission. [ABSTRACT FROM AUTHOR]

In this study, microstructural variation of hydroxyapatite (HAp) ceramics upon thermal treatment in air at different temperatures was investigated by x-ray diffraction patterns, Raman and x-ray photoelectron spectroscopies. The results revealed a significant dependence of the microstructure of nonstoichiometric HAp on temperature, because of the competition between hydroxylation and different kinds of dehydroxylation at different temperatures, and a gradual increase in material hardness with annealing temperature because of structural reconstruction. In summary, a suitable thermal treatment can effectively tailor microstructure and defect contents, as well as chemical composition and mechanical hardness of HAp ceramics. [ABSTRACT FROM AUTHOR]

Intrahepatic cholangiocarcinoma (iCCA) is a heterogeneous bile duct cancer with a poor prognosis. Integrin αvβ6 (β6) has been shown to be upregulated in iCCA and is associated with its subclassification and clinicopathological features. In the present study, two ITGB6-knockout HuCCT1 CCA cell lines (ITGB6-ko cells) were established using the clustered regulatory interspaced short palindromic repeats (CRISPR), an associated nuclease 9 (Cas9) system, and single-cell cloning. RNA sequencing analysis, real-time polymerase chain reaction (PCR), and immunofluorescent methods were applied to explore possible downstream factors. ITGB6-ko cells showed significantly decreased expression of integrin β6 on flow cytometric analysis. Both cell lines exhibited significant inhibition of cell migration and invasion, decreased wound-healing capability, decreased colony formation ability, and cell cycle dysregulation. RNA sequencing and real-time PCR analysis revealed a remarkable decrease in podocalyxin-like protein 2 (PODXL2) expression in ITGB6-ko cells. Colocalization of PODXL2 and integrin β6 was also observed. S100 calcium-binding protein P and mucin 1, which are associated with CCA subclassification, were downregulated in ITGB6-ko cells. These results describe the successful generation of ITGB6-ko CCA cell clones with decreased migration and invasion and downregulation of PODXL2, suggesting the utility of integrin β6 as a possible therapeutic target or diagnostic marker candidate. [ABSTRACT FROM AUTHOR]

The transplantation of engineered three-dimensional (3D) bone graft substitutes is a viable approach to the regeneration of severe bone defects. For large bone defects, an appropriate 3D scaffold may be necessary to support and stimulate bone regeneration, even when a sufficient number of cells and cell cytokines are available. In this study, we evaluated the in vivo performance of a nanogel tectonic 3D scaffold specifically developed for bone tissue engineering, referred to as nanogel cross-linked porous-freeze-dry (NanoCliP-FD) gel. Samples were characterized by a combination of micro-computed tomography scanning, Raman spectroscopy, histological analyses, and synchrotron radiation–based Fourier transform infrared spectroscopy. NanoCliP-FD gel is a modified version of a previously developed nanogel cross-linked porous (NanoCliP) gel and was designed to achieve highly improved functionality in bone mineralization. Spectroscopic imaging of the bone tissue grown in vivo upon application of NanoCliP-FD gel enables an evaluation of bone quality and can be employed to judge the feasibility of NanoCliP-FD gel scaffolding as a therapeutic modality for bone diseases associated with large bone defects. [ABSTRACT FROM AUTHOR]

A two-stage selection process was applied to eight oleaginous yeast strains from the Lipomyces genera. In the primary selection stage, a nitrogen-limited mineral medium (-NMM) that contained a mixture of glucose and xylose as a carbon source was used to evaluate the lipid-accumulating abilities of the yeast strains. The strains L. doorenjongii , L. orientalis , and L. starkeyi were selected as the potential strains in the primary selection. These three strains exhibited a remarkable ability to simultaneously assimilate glucose and xylose and achieved a cell biomass of more than 30 g/L. The values for lipid content in the selected strains were 57.89 ± 1.92, 56.38 ± 1.93, and 77.14 ± 1.55% for L. doorenjongii , L. orientalis , and L. starkeyi , respectively. In the secondary selection, when the -NMM medium contained an inhibitory chemical compound (ICC), the selected strains showed a different tolerance level against each of the typical inhibitor compounds. However, L. starkeyi accumulated the highest lipid content and yield at 68.24 ± 2.48% and 0.19 ± 0.00 (w/w), respectively. L. starkeyi accumulated high levels of intracellular lipid and tolerated the ICC. The composition of fatty acid methyl esters (FAMEs) was unaltered by the presence of ICC and the major FAMEs consisted of oleic, palmitic, stearic, palmitoleic and linoleic acids. [ABSTRACT FROM AUTHOR]

Oleaginous microbes can convert substrates such as carbon dioxide, sugars, and organic acids to single-cell oils (SCOs). Among the oleaginous microorganisms, Lipomyces starkeyi is a particularly well-suited host given its impressive native abilities, including the capability to utilize a wide variety of carbon sources. In this work, the potential of L. starkeyi NBRC10381 to produce SCOs in a synthetically nitrogen-limited mineral medium (-NMM) was investigated by differing the inoculum size using glucose and/or xylose as a carbon source. Fermentation using glucose and xylose as mixed carbon sources generated the highest production of biomass at 40.8 g/L, and achieved a lipid content of 84.9% (w/w). When either glucose or xylose was used separately, the totals for achieved lipid content were 79.6% (w/w) and 85.1% (w/w), respectively. However, biomass production was higher for glucose than for xylose (30.3 vs. 28.7 g/L, respectively). This study describes the first simultaneous achievement of higher levels of cell mass and lipid production using glucose and/or xylose as the carbon sources in different inoculum sizes. [ABSTRACT FROM AUTHOR]

In this study, we monitored the effect of Al3+ ions on mesenchymal cells (KUSA-A1) and human fibroblasts (NHDF) by means of in vitro experiments by culturing the cells with addition of small concentrations of aluminum ions (i.e. , 0.1, 1, 10, and 100 ppm). Bone formation test was then conducted using KUSA-A1. Small concentrations of aluminum ions delayed but did not completely inhibit cell proliferation. The amount of bone tissue decreased as the concentration of Al3+ increased and crystallinity changes were also detected by Raman spectroscopic experiments. Moreover, Al3+ ions greatly affected both structure and chemistry of bone tissues with mineral nodules becoming larger and atomic substitution of Ca with Al in bone tissue being more preponderant with increasing Al3+ concentration. Such effects in turn impaired the balance between mineral and collagen in the formed bone tissue. [Display omitted] • The effect for cell proliferation of aluminum ions depends on cell types. • KUSA-A1's proliferation was promoted with increasing the amount of aluminum ions. • Aluminum substitutes calcium in the mineral apatite of bone tissues. • Larger bone mineral nodules were observed. [ABSTRACT FROM AUTHOR]

• The fermentation of Ls-D35 was carried out at low initial C/N ratio (17.9). • The fermentation of Ls-D35 was optimum at pH 5 for cell and lipid productions. • The highest lipid yield was achieved by using single xylose feeding. Oleaginous microorganisms such as oleaginous yeasts are well known for the ability to accumulate intracelular lipid more than 20% w/w in certain conditions. Lipomyces starkeyi D35 (Ls-D35 strain) is one of promising oleaginous yeast for lipid production. The purpose of this research is to establish the optimum condition for cell and lipid production of Ls-D35 strain under low C/N ratio (17.9) by high cell density cultivation. The optimum pH for cell and lipid production was achieved at pH 5 by using batch cultivation. Four different feeding strategies were conducted to observe the cell and lipid production of Ls-D35 strain. The highest cell yield was achieved by mixed glucose and xylose as substrates (0.15 w/w substrate) after 96 h and the highest lipid yield was achieved by single xylose feeding (0.13 w/w substrate) after 120 h. Meanwhile, the two most fatty acids content were C18:1 and C16:0 which are similar to the content of vegetable oil. These results showed that Ls-D35 strain could produce high cell and optimum lipid under low initial C/N ratio medium which can be an alternative for biodiesel production and other industrial products. [ABSTRACT FROM AUTHOR]