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571.
A 10-day old male calf exhibited multiple congenital anomalies of the urinary and gastrointestinal tracts, including renal fusion (horseshoe kidney), ureteral fusion, rectovesicular fistula, and atresia ani. In horseshoe kidney, the organs were fused together at the caudal poles. The left kidney and cranial half of right kidney were shrunken, while the remaining lobules were hypertrophic. Ureters were fused cranially and bifurcated caudally. The terminal rectum was narrowed and connected with the bladder. The anus was imperforate. The cause of these anomalies could not be determined.  相似文献   
572.
The genetic relatedness of 7 Korean type O field strains of foot-and-mouth disease virus (FMDV) in clinical specimens collected from 5 different geographic locations in 2000 was investigated. The sequence of 162 nucleotides (nt 478-639) at the 3' end of the 1D (VP1) genes was determined from amplified cDNA fragments, and subjected to the analysis for the sequence identity/divergence and phylogenetic relationship. The overall nucleotide sequence divergence among the 7 field strains was 0 to 3.8%, suggesting that they are closely related to each other. Phylogenetic analysis with the known Middle East-South Asia (ME-SA) topotype strains showed that the 7 Korean field strains formed two distinct clusters within the same lineage of the ME-SA topotype strains. Cluster 1 consisted of the strains of the primary foci of infection (Paju and Hongseong), and closely related to the strains prevailed in the Far East. Cluster 2 comprised those of subsequently affected regions (Boryeong, Yongin, and Chungju), and was further diverged from the Cluster 1. The result of phylogenetic analysis indicated that the Korean strains may have evolved from a common ancestor of the Pan Asia strains, and that at least 2 phylogenetically clustered variants within the same lineage were prevalent during the epidemic. The potential origin and sources of the virus introduction to Korea were discussed.  相似文献   
573.
The mitotic index is reported to be correlated with recurrence, mean patient survival, and metastasis of canine hemangiopericytoma (CHP). However, to the authors' knowledge, studies investigating the parameters that can predict recurrence or metastasis of CHP with low mitotic index have not been done. To evaluate growth kinetics of CHP with low mitotic index, a retrospective analysis of the proliferative activity by antiproliferative cell nuclear antigen monoclonal antibody and DNA contents by flow cytometry (FCM) was performed with 21 formalin-fixed and paraffin-embedded CHP samples. Of the 21 tumors evaluated by FCM, 6 (26.6%) were aneuploid tumors, and 15 (71.4%) were diploid tumors. There was significant correlation between the PCNA index and ploidy pattern. The diploid group had 39.1 +/- 9.2 PCNA index, whereas the aneuploid group's proliferative cell nuclear antigen (PCNA) index was 63.1 +/- 8.2. The diploid group had mean mitotic index value of 1.140 +/- 0.855, and the aneuploid group had a mean value of 1.067 +/- 0.767. From these results, the CHP samples with low mitotic index were classified into either the aneuploid group with higher PCNA index or the diploid group with lower PCNA index, suggesting that DNA ploidy and proliferative activity may give an indication about malignancy of CHPs with a low mitotic index.  相似文献   
574.
Currently, periodontitis treatment relies on surgical operations, anti-inflammatory agents, or antibiotics. However, these treatments cause pain and side effects, resulting in a poor prognosis. Therefore, in this study, we evaluated the impact of the compound epiloliolide isolated from Sargassum horneri on the recovery of inflammatory inhibitors and loss of periodontal ligaments, which are essential treatment strategies for periodontitis. Here, human periodontal ligament cells stimulated with PG-LPS were treated with the compound epiloliolide, isolated from S. horneri. In the results of this study, epiloliolide proved the anti-inflammatory effect, cell proliferation capacity, and differentiation potential of periodontal ligament cells into osteoblasts, through the regulation of the PKA/CREB signaling pathway. Epiloliolide effectively increased the proliferation and migration of human periodontal ligament cells without cytotoxicity and suppressed the protein expression of proinflammatory mediators and cytokines, such as iNOS, COX-2, TNF-α, IL-6, and IL-1β, by downregulating NLRP3 activated by PG-LPS. Epiloliolide also upregulated the phosphorylation of PKA/CREB proteins, which play an important role in cell growth and proliferation. It was confirmed that the anti-inflammatory effect in PG-LPS-stimulated large cells was due to the regulation of PKA/CREB signaling. We suggest that epiloliolide could serve as a potential novel therapeutic agent for periodontitis by inhibiting inflammation and restoring the loss of periodontal tissue.  相似文献   
575.
BackgroundHypoxia causes oxidative stress and affects cardiovascular function and the programming of cardiovascular disease. Melatonin promotes antioxidant enzymes such as superoxide dismutase, glutathione reductase, glutathione peroxidase, and catalase.ObjectivesThis study aims to investigate the correlation between melatonin and hypoxia induction in cardiomyocytes differentiation.MethodsMouse embryonic stem cells (mESCs) were induced to myocardial differentiation. To demonstrate the influence of melatonin under hypoxia, mESC was pretreated with melatonin and then cultured in hypoxic condition. The cardiac beating ratio of the mESC-derived cardiomyocytes, mRNA and protein expression levels were investigated.ResultsUnder hypoxic condition, the mRNA expression of cardiac-lineage markers (Brachyury, Tbx20, and cTn1) and melatonin receptor (Mtnr1a) was reduced. The mRNA expression of cTn1 and the beating ratio of mESCs increased when melatonin was treated simultaneously with hypoxia, compared to when only exposed to hypoxia. Hypoxia-inducible factor (HIF)-1α protein decreased with melatonin treatment under hypoxia, and Mtnr1a mRNA expression increased. When the cells were exposed to hypoxia with melatonin treatment, the protein expressions of phospho-extracellular signal-related kinase (p-ERK) and Bcl-2-associated X proteins (Bax) decreased, however, the levels of phospho-protein kinase B (p-Akt), phosphatidylinositol 3-kinase (PI3K), B-cell lymphoma 2 (Bcl-2) proteins, and antioxidant enzymes including Cu/Zn-SOD, Mn-SOD, and catalase were increased. Competitive melatonin receptor antagonist luzindole blocked the melatonin-induced effects.ConclusionsThis study demonstrates that hypoxia inhibits cardiomyocytes differentiation and melatonin partially mitigates the adverse effect of hypoxia in myocardial differentiation by regulating apoptosis and oxidative stress through the p-AKT and PI3K pathway.  相似文献   
576.
In this retrospective, analytical study, we developed a deep learning-based diagnostic model that can be applied to canine stifle joint diseases and compared its accuracy with that achieved by veterinarians to verify its potential as a reliable diagnostic method. A total of 2382 radiographs of the canine stifle joint from cooperative animal hospitals were included in a dataset. Stifle joint regions were extracted from the original images using the faster region-based convolutional neural network (R-CNN) model, and the object detection accuracy was evaluated. Four radiographic findings: patellar deviation, drawer sign, osteophyte formation, and joint effusion, were observed in the stifle joint and used to train a residual network (ResNet) classification model. Implant and growth plate groups were analyzed to compare the classification accuracy against the total dataset. All deep learning-based classification models achieved target accuracies exceeding 80%, which is comparable to or slightly less than those achieved by veterinarians. However, in the case of drawer signs, further research is necessary to improve the low sensitivity of the model. When the implant group was excluded, the classification accuracy significantly improved, indicating that the implant acted as a distraction. These results indicate that deep learning-based diagnoses can be expected to become useful diagnostic models in veterinary medicine.  相似文献   
577.
Graphene produced by exfoliation has not been able to provide an ideal graphene with performance comparable to that predicted by theory, and structural and/or electronic defects have been proposed as one cause of reduced performance. We report the observation of domains on exfoliated monolayer graphene that differ by their friction characteristics, as measured by friction force microscopy. Angle-dependent scanning revealed friction anisotropy with a periodicity of 180° on each friction domain. The friction anisotropy decreased as the applied load increased. We propose that the domains arise from ripple distortions that give rise to anisotropic friction in each domain as a result of the anisotropic puckering of the graphene.  相似文献   
578.
BackgroundWe previously elucidated the protective mechanism of Korean red ginseng oil (RGO) against Brucella abortus infection, and our phytochemical analysis revealed that palmitic acid (PA) was an abundant component of RGO. Consequently, we investigated the contribution of PA against B. abortus.ObjectivesWe aimed to investigate the efficacy of PA against B. abortus infection using a murine cell line and a murine model.MethodsCell viability, bactericidal, internalization, and intracellular replication, western blot, nitric oxide (NO), and superoxide (O2-) analyses and flow cytometry were performed to determine the effects of PA on the progression of B. abortus infection in macrophages. Flow cytometry for cytokine analysis of serum samples and bacterial counts from the spleens were performed to determine the effect of PA in a mouse model.ResultsPA did not affect the growth of B. abortus. PA treatment in macrophages did not change B. abortus uptake but it did attenuate the intracellular survivability of B. abortus. Incubation of cells with PA resulted in a modest increase in sirtuin 1 (SIRT1) expression. Compared to control cells, reduced nitrite accumulation, augmented O2-, and enhanced pro-inflammatory cytokine production were observed in PA-treated B. abortus-infected cells. Mice orally treated with PA displayed a decreased serum interleukin-10 level and enhanced bacterial resistance.ConclusionsOur results suggest that PA participates in the control of B. abortus within murine macrophages, and the in vivo study results confirm its efficacy against the infection. However, further investigations are encouraged to completely characterize the mechanisms involved in the inhibition of B. abortus infection by fatty acids.  相似文献   
579.
A methodology for the objective evaluation of water repellency is studied using image analysis of the sprayed pattern on woven fabrics according to a standard spray test (AATCC Test Method 22-2001). The wet area ratio obtained from the spray standard test ranking is found to be exponentially related with its water repellency rating. Mean filtering is used to remove the effect of weave texture and the transmitted light through interyarn spaces. The ring frame of the instrument and wet region are recognized using Otsu thresholding technique. And Hough transform and outline operation are used to obtain the size and position of the ring frame. The objective assessment of the water repellency using image processing can reduce unnecessary confusion in the subjective determination of the water repellency.  相似文献   
580.
In order to prepare high molecular weight poly(methyl methacrylate) (PMMA)/silver nanocomposite microspheres, methyl methacrylate was suspension-polymerized in the presence of silver nanoparticles at low temperature with 2,2′-azobis(2,4-dimethylvaleronitrile) as an initiator. The rate of conversion was increased by increasing the initiator concentration. When silver nanoparticles were added, the rate of polymerization decreased slightly. High monomer conversion (about 85 %) was obtained in spite of low polymerization temperature of 30°C. Under controlled conditions, PMMA/silver microspheres with various number-average degrees of polymerization (6,000–37,000) were prepared. Morphology studies revealed that except for normal suspension microspheres with a smooth surface, a golf ball-like appearance of the microspheres was observed, due to the migration and aggregation of the hydrophilic silver nanoparticles at the sublayer beneath the microsphere’s surface.  相似文献   
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