1,544 research outputs found
Polarity engineering in polycrystalline ZnO by inversion boundaries
Two distinctive polarity-engineered microstructures were obtained in polycrystalline ZnO ceramics by inducing two different types of inversion boundaries (IBs) inside individual grains to examine the effect of the different polarities on the varistor performances. The presence of head-to-head IBs induced by the addition of Sb and tail-to-tail IBs by doping Ti was directly confirmed by the characteristic geometry of the chemical etch pits. It was proposed that a consequent polarity on the grain boundary planes, which are affected by the presence of head-to-head IBs is crucial in exhibiting the superior performance of ZnO varistors.open2
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AKAP12 Mediates Barrier Functions of Fibrotic Scars during CNS Repair
The repair process after CNS injury shows a well-organized cascade of three distinct stages: inflammation, new tissue formation, and remodeling. In the new tissue formation stage, various cells migrate and form the fibrotic scar surrounding the lesion site. The fibrotic scar is known as an obstacle for axonal regeneration in the remodeling stage. However, the role of the fibrotic scar in the new tissue formation stage remains largely unknown. We found that the number of A-kinase anchoring protein 12 (AKAP12)-positive cells in the fibrotic scar was increased over time, and the cells formed a structure which traps various immune cells. Furthermore, the AKAP12-positive cells strongly express junction proteins which enable the structure to function as a physical barrier. In in vivo validation, AKAP12 knock-out (KO) mice showed leakage from a lesion, resulting from an impaired structure with the loss of the junction complex. Consistently, focal brain injury in the AKAP12 KO mice led to extended inflammation and more severe tissue damage compared to the wild type (WT) mice. Accordingly, our results suggest that AKAP12-positive cells in the fibrotic scar may restrict excessive inflammation, demonstrating certain mechanisms that could underlie the beneficial actions of the fibrotic scar in the new tissue formation stage during the CNS repair process
Highly malignant soft tissue sarcoma of the extremity with a delayed diagnosis
<p>Abstract</p> <p>Purpose</p> <p>To evaluate the characteristics of highly malignant soft tissue sarcoma of the extremity with a delayed diagnosis.</p> <p>Materials and methods</p> <p>The clinical and radiological characteristics of 18 cases of highly malignant soft tissue sarcomas of the extremity with a delayed diagnosis were determined.</p> <p>Results</p> <p>Ten men and eight women of mean age 44.8 years (range, 15-79 years) were included in this study. Seven cases of synovial sarcoma, three cases each of alveolar soft part sarcoma and malignant fibrous histiocytoma, two cases each of highly malignant leiomyosarcoma and myxofibrosarcoma, and one case of clear cell sarcoma were enrolled. Times from tumor detection to diagnosis ranged from 1 to 3 years in most cases; three of the seven synovial sarcoma cases took more than 10 years to diagnose. Of the seven cases of synovial sarcoma, five cases of small, superficial located masses were simply excised without a pre-surgical biopsy. Three cases of alveolar soft part sarcoma showed characteristic T1- and T2-weighted high signal intensities with signal voids in MR images. In addition, one synovial sarcoma patient and one alveolar soft part sarcoma patient showed evidence of calcification on plain radiographs. However, no general characteristic clinical findings were found to be common to the 18 cases.</p> <p>Conclusions</p> <p>Contrary to general expectations, some soft tissue tumors that grow slowly are painless, and those that occur in superficial limbs may be highly malignant. Thus, even when a slow growing, painless superficial mass is encountered in a limb, physicians should keep the possibility of highly malignant soft tissue sarcoma in mind.</p
Transphyseal Reconstruction of the Anterior Cruciate Ligament Using Hamstring Autograft in Skeletally Immature Adolescents
Eleven skeletally immature adolescents underwent anterior cruciate ligament reconstruction using a transphyseal tibial and femoral tunnel. An autologous quadrupled hamstring tendon was used in all cases and the average follow-up was 77.7 months. Clinical results were evaluated using Lysholm knee scores and a return to pre-injury sports activities. Radiological results were evaluated using side-to-side differences of instrumented laxities and growth disturbances compared with the uninjured side on final follow-up orthoroentgenograms. The mean Lysholm score was 97.8 (range 94-100) and mean side-to-side laxity difference was 2.4 mm (range 1-4). Ten of 11 patients returned to pre-injury sports activity. No patient had a leg length discrepancy of over 1 cm or a significant abnormal angular deformity of the knee joint. Therefore, anterior cruciate ligament reconstruction using the transphyseal tunnel and hamstring autograft in skeletally immature adolescents is believed to be a reliable treatment method, which is not associated with significant leg length discrepancy or abnormal angular deformity of the knee joint
Arthroscopic Repair of Combined Bankart and SLAP Lesions: Operative Techniques and Clinical Results
Is Conservative Treatment with Antibiotics the Correct Strategy for Management of Right Colonic Diverticulitis?: A Prospective Study
Fungal Invasion of Normally Non-Phagocytic Host Cells
Many fungi that cause invasive disease invade host epithelial cells during mucosal and respiratory infection, and subsequently invade endothelial cells during hematogenous infection. Most fungi invade these normally non-phagocytic host cells by inducing their own uptake. Candida albicans hyphae interact with endothelial cells in vitro by binding to N-cadherin on the endothelial cell surface. This binding induces rearrangement of endothelial cell microfilaments, which results in the endocytosis of the organism. The capsule of Cryptococcus neoformans is composed of glucuronoxylomannan, which binds specifically to brain endothelial cells, and appears to mediate both adherence and induction of endocytosis. The mechanisms by which other fungal pathogens induce their own uptake are largely unknown. Some angioinvasive fungi, such as Aspergillus species and the Zygomycetes, invade endothelial cells from the abluminal surface during the initiation of invasive disease, and subsequently invade the luminal surface of endothelial cells during hematogenous dissemination. Invasion of normally non-phagocytic host cells has different consequences, depending on the type of invading fungus. Aspergillus fumigatus blocks apoptosis of pulmonary epithelial cells, whereas Paracoccidioides brasiliensis induces apoptosis of epithelial cells. This review summarizes the mechanisms by which diverse fungal pathogens invade normally non-phagocytic host cells and discusses gaps in our knowledge that provide opportunities for future research
Comparison of two high-throughput semiconductor chip sequencing platforms in noninvasive prenatal testing for Down syndrome in early pregnancy
Background: Noninvasive prenatal testing (NIPT) to detect fetal aneuploidy using next-generation sequencing on ion semiconductor platforms has become common. There are several sequencers that can generate sufficient DNA reads for NIPT. However, the approval criteria vary among platforms and countries. This can delay the introduction of such devices and systems to clinics. A comparison of the sensitivity and specificity of two different platforms using the same sequencing chemistry could be useful in NIPT for fetal chromosomal aneuploidies. This would improve healthcare authorities' confidence in decision-making on sequencing-based tests.
Methods: One hundred and one pregnant women who were predicted at high risk of fetal defects using conventional prenatal screening tests, and who underwent definitive diagnosis by full karyotyping, were enrolled from three hospitals in Korea. Most of the pregnant women (69.79 %) received NIPT during weeks 11-13 of gestation and 30.21 % during weeks 14-18. We used Ion Torrent PGM and Proton semi-conductor-based sequencers with 0.3x sequencing coverage depth. The average total reads of 101 samples were approximately 4.5 and 7.6 M for PGM and Proton, respectively. A Burrows-Wheeler Aligner (BWA) algorithm was used for the alignment, and a z-score was used to decide fetal trisomy 21. Interactive dot diagrams from the sequencing data showed minimal z-score values of 2.07 and 2.10 to discriminate negative versus positive cases of fetal trisomy 21 for the two different sequencing systems.
Results: Our z-score-based discrimination method resulted in 100 % positive and negative prediction values for both ion semiconductor PGM and Proton sequencers, regardless of their sequencing chip and chemistry differences. Both platforms performed well at an early stage (11-13 weeks of gestation) compared with previous studies.
Conclusions: These results suggested that, using two different sequencers, NIPT to detect fetal trisomy 21 in early pregnancy is accurate and platform-independent. The data suggested that the amount of sequencing and the application of common, simple, and robust statistical analyses are more important than sequencing chemistry and platform types. This result has practical implications in countries where PGM is approved for NIPT but the Proton system is not.ope
Differences in the patterns and outcomes of enhanced viral replication between hepatitis C virus and hepatitis B virus in patients with hepatocellular carcinoma during transarterial chemolipiodolization
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