9 research outputs found
Transplantation of Neural Stem Cells in Anosmic Mice
ObjectivesTreating olfactory dysfunction is a challenge for physicians. One of the therapeutic options could be transplantation of stem cells. In this study, neural stem cells were transplanted into anosmic mice.MethodsNeural stem cells were generated from the olfactory bulb of green fluorescent protein (GFP)-transgenic C57BL6 mice. Anosmia were induced by injection of intraperitoneal 3-methylindole. The neural stem cells were transplanted transnasally on the next day. The olfactory function was evaluated by a food-finding test once a week. The olfactory neuroepithelium was harvested for histologic examination and protein analysis at 4 weeks.ResultsTwenty-five percent (6/24) of the control mice that were not transplanted with neural stem cells survived at 4 weeks while 67% (8/12) of the transplanted mice survived (P=0.029). The food finding test showed that the transplanted mice resumed finding food at 3 weeks while the control mice resumed finding food at 4 weeks. GFP-positive cells were observed in the olfactory neuroepithelium of the transplanted mice. Western blotting revealed that the olfactory marker protein expression was significantly lower in the control mice than that in the transplanted mice.ConclusionThis study demonstrated that improvement of mouse survival was achieved and recovery of olfactory function was promoted by transnasal transplantation of neural stem cells in the anosmic mouse model. These results indicate that stem cells might be one of the future modalities for treating olfactory impairment
Effects of Annealing Temperature on Microstructural Evolution and Mechanical Properties in Cold-Rolled High-Nitrogen Austenitic Steel
High-nitrogen austenitic steel (HNS) cold-rolled with a reduction rate of 25% was subjected to an investigation of the effect of annealing temperature on microstructural evolution, tensile properties and the variation in fracture surface morphology. In cold-rolled HNS, matrix recovery occurred at an annealing temperature of 600 °C, and recrystallization was locally initiated at an annealing temperature of 800 °C. The 0.2% offset yield strength (0.2% YS) and ultimate tensile strength (UTS) were almost constant up to an annealing temperature of 500 °C, and these values gradually decreased above the annealing temperature of 600 °C, while a sharp reduction in the percentage reduction in area (RA) occurred at the annealing temperatures of 600 and 700 °C due to Cr2N precipitation along the grain and twin boundaries. The ratio of 0.2% offset yield strength to ultimate tensile strength (0.2% YS/UTS) remained constant until matrix recovery took place; however, once recrystallization occurred, the ratio decreased significantly. Furthermore, the variation in the morphology of Cr2N along the grain boundaries in the annealing temperature range from 600 to 800 °C influenced the intergranular fracture morphology, resulting in a transition from dimple to ledge and back to dimple
Microstructure, Tensile, and Fatigue Properties of Large-Scale Austenitic Lightweight Steel
High-Mn lightweight steel, Fe-0.9C-29Mn-8Al, was manufactured using steelmaking, ingot-making, forging, and rolling processes. After the final rolling process, a typical austenite single phase was observed on all sides of the thick plate. The microstructural changes after annealing and aging heat-treatments were observed, using optical and transmission electron microscopy. The annealed coupon exhibited a typical austenite single phase, including annealing twins in several grains; the average grain size was 153 μm. After aging heat treatment, κ-carbide was observed within the grains and on the grain boundaries. Additionally, the effect of aging heat treatment on the mechanical properties was analyzed, using a tensile test. The fine κ-carbide that precipitated within the grains in the aged coupon improved the 0.2% offset yield and the tensile stresses, as compared to the as-annealed coupon. To estimate the applicability of high-Mn lightweight steel for low-pressure (LP) steam turbine blades, a low-cycle fatigue (LCF) test was carried out at room temperature. At a total strain amplitude of 0.5 to 1.2%, the LCF life of high-Mn lightweight steel was approximately three times that of 12% Cr steel, which is used in commercial LP steam turbine blades. The LCF behavior of high-Mn lightweight steel followed the Coffin–Manson equation. The LCF life enhancement in the high-Mn lightweight steel results from the planar dislocation gliding behavior
Computed Tomography and F-18-fluoro-2-deoxyglucose Positron Emission Tomography Findings of Primary Pulmonary Follicular Dendritic Cell Sarcoma Case Report and a Literature Review
We report herein computed tomography and F-18-fluoro-2-deoxyglucose positron emission tomography findings of primary pulmonary follicular dendritic cell sarcoma in a 51-year-old man, which is an extremely rare malignancy originating from follicular dendritic cells. Computed tomography scan revealed a 2.4-cm, well-defined solitary pulmonary nodule with delayed contrast enhancement but without regional lymphadenopathy, distant metastasis, or calcification within the nodule. On F-18-fluoro-2-deoxyglucose positron emission tomography scan, this nodule showed moderate hypermetabolic activity with a maximum standardized uptake value of 3.2.N
HOX gene analysis in the osteogenic differentiation of human mesenchymal stem cells
Human bone marrow-derived mesenchymal stem cells (hMSCs) have the capacity to differentiate into osteoblasts during osteogenesis. Several studies attempted to identify osteogenesis-related genes in hMSCs. Although HOX genes are known to play a pivotal role in skeletogenesis, their function in the osteogenesis of hMSCs has not yet been investigated in detail. Our aim was to characterize the expression of 37 HOX genes by multiplex RT-PCR to identify the ones most probably involved in osteogenic differentiation. The results showed that the expression patterns of four HOX genes were altered during this process. In particular, the expression levels of HOXC13 and HOXD13 were dramatically changed. Real-time PCR and Western blot analysis were performed in order to further analyze the expression of HOXC13 and HOXD13 . The qRT-PCR results showed that transcription of HOXC13 was up-regulated by up to forty times, whereas that of HOXD13 was down-regulated by approximately five times after osteogenic differentiation. The Western blot results for the HOXC13 and HOXD13 proteins also corresponded well with the real-time PCR result. These findings suggest that HOXC13 and HOXD13 might be involved in the osteogenic differentiation of hMSCs
A newly developed capture-based sequencing panel for genomic assay of lung cancer
Background The increase in genetic alterations targeted by specific chemotherapy in lung cancer has led to the need for universal use of more comprehensive genetic testing, which has highlighted the development of a lung cancer diagnostic panel using next-generation sequencing. Objective We developed a hybridization capture-based massively parallel sequencing assay named Friendly, Integrated, Research-based, Smart and Trustworthy (FIRST)-lung cancer panel (LCP), and evaluated its performance. Methods FIRST-LCP comprises 64 lung cancer-related genes to test for various kinds of genetic alterations including single nucleotide variations (SNVs), insertions and deletions (indels), copy number variations (CNVs), and structural variations. To assess the performance of FIRST-LCP, we compiled test sets using HapMap samples or tumor cell lines with disclosed genetic information, and also tested our clinical lung cancer samples whose genetic alterations were known by conventional methods. Results FIRST-LCP accomplished high sensitivity (99.4%) and specificity (100%) of the detection of SNVs. High precision was also achieved, with intra- or inter-run concordance rate of 0.99, respectively. FIRST-LCP detected indels and CNVs close to the expected allele frequency and magnitude, respectively. Tests with samples from lung cancer patients also identified all SNVs, indels and fusions. Conclusion Based on the current state of the art, continuous application of the panel design and analysis pipeline following up-to-date knowledge could ensure precision medicine for lung cancer patients.