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A new method to realize the optical perfect shuffle (PS) with a microoptical array element is presented in this paper. The whole process is simulated by computer, and parameters of the structure to fabricate the experimental component are given. The microoptical array element has been fabricated by introducing very large scale integration (VLSI), stepping photolithography and reactive iron etching (RIE), which can realize 8-channel PS transformation. Experiments, tests and analysis have been done using the array element. The experimental results show that the method proposed in this paper agrees well with theoretical expectation. This success of the experiment lays a good foundation for us to do further research on realization of optical switching and communication through cascade multilevel PS interconnection.
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OBJECTIVE: Urethral stricture is a common condition seen after urethral injury. The currently available treatments are inadequate and there is a scarcity of substitute materials used for treatment of urethral stricture. The traditional tissue engineering of urethra involves scaffold design, fabrication and processing of multiple cell types. METHODS: In this study, we have used 3D bioprinting technology to fabricate cell-laden urethra in vitro with different polymer types and structural characteristics. We hypothesized that use of PCL and PLCL polymers with a spiral scaffold design could mimic the structure and mechanical properties of natural urethra of rabbits, and cell-laden fibrin hydrogel could give a better microenvironment for cell growth. With using an integrated bioprinting system, tubular scaffold was formed with the biomaterials; meanwhile, urothelial cells (UCs) and smooth muscle cells (SMCs) were delivered evenly into inner and outer layers of the scaffold separately within the cell-laden hydrogel. RESULTS: The PCL/PLCL (50:50) spiral scaffold demonstrated mechanical properties equivalent to the native urethra in rabbit. Evaluation of the cell bioactivity in the bioprinted urethra revealed that UCs and SMCs maintained more than 80% viability even at 7days after printing. Both cell types also showed active proliferation and maintained the specific biomarkers in the cell-laden hydrogel. CONCLUSION: These results provided a foundation for further studies in 3D bioprinting of urethral constructs that mimic the natural urethral tissue in mechanical properties and cell bioactivity, as well a possibility of using the bioprinted construct for in vivo study of urethral implantation in animal model. SIGNIFICANCE OF STATEMENTS: The 3D bioprinting is a new technique to replace traditional tissue engineering. The present study is the first demonstration that it is feasible to create a urethral construct. Two kinds of biomaterials were used and achieved mechanical properties equivalent to that of native rabbit urethra. Bladder epithelial cells and smooth muscle cells were loaded in hydrogel and maintained sufficient viability and proliferation in the hydrogel. The highly porous scaffold could mimic a natural urethral base-membrane, and facilitate contacts between the printed epithelial cells and smooth muscle cells on both sides of the scaffold. These results provided a strong foundation for future studies on 3D bioprinted urethra.
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Materiais Biomiméticos/química , Hidrogéis/química , Miócitos de Músculo Liso/metabolismo , Impressão Tridimensional , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Uretra , Urotélio/metabolismo , Animais , Linhagem Celular , Masculino , Teste de Materiais , Miócitos de Músculo Liso/citologia , Poliésteres/química , Coelhos , Urotélio/citologiaRESUMO
Some RNA species, especially microRNAs, are non-randomly sorted into exosomes, but how selectivity of RNA exosomal sorting is achieved is unknown. We found that all three variants of RNA-binding ubiquitin E3 ligase (MEX3C)-MEX3C-1, MEX3C-2, and MEX3C-3 -interact with adaptor-related protein complex 2 (AP-2), a cargo adaptor in clathrin-mediated endocytosis. MEX3C's C-terminal RING finger domain and the hnRNP K homology (KH) domain shared by the three MEX3C variants are both necessary for MEX3C/AP-2 interaction. MEX3C associates with the endolysosomal compartment through an endocytosis-like process. siRNA-mediated inhibition of the MEX3C or AP-2 complex substantially decreased exosomal but not cellular microRNA miR-451a expression. Exosomal sorting is ceramide-dependent but not ESCRT-dependent in microRNA miR-451a. That RNA-binding protein associates with membrane trafficking machinery, and that its involvement in exosomal microRNA expression, suggest the existence of a mechanism for specific recruiting of RNA molecules to endosomes for subsequent exosomal sorting.
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Complexo 2 de Proteínas Adaptadoras/metabolismo , Exossomos/metabolismo , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Células HEK293 , Humanos , Camundongos , Ligação ProteicaRESUMO
PURPOSE: To apply massage therapy accompanied with stretching exercises for treatment of mammary gland hyperplasia, evaluate the clinical outcome in patients, and estimate the therapy as a novel treatment method for mammary hyperplasia. METHODS: 28 adult female patients were selected and treated with massage therapy and stretching exercises focusing on skeleton muscles of chest, abdomen, and axilla. The mammary gland oxyhemoglobin (OxyHb) and deoxyhemoglobin (DeoxyHb) levels were detected before and after treatment after 15, 30, and 45 days. RESULTS: In this cohort, pretreatment OxyHb (mean ± SD) is 1.32 ± 0.14 (medium-high), and DeoxyHb is 0.87 ± 0.13 (normal). All patients were clinically diagnosed with benign mammary gland hyperplasia and mastitis. The posttreatment OxyHb levels are 1.23 ± 0.09 (normal-medium, 15-day), 1.16 ± 0.08 (normal, 30-day), and 1.05 ± 0.04 (normal, 45-day), and DeoxyHb levels are 0.90 ± 0.11 (normal, 15-day), 0.94 ± 0.18 (normal, 30-day), and 0.98 ± 0.12 (normal, 45-day). Patients were diagnosed with decreased hyperplasia 15 and 30 days after treatment and with no symptom of hyperplasia in mammary gland 45 days after treatment. CONCLUSION: Mammary gland hyperplasia is closely correlated with pathological changes of skeletal muscles and could be significantly improved by massage therapy and stretching exercises targeting neighboring skeletal muscles.
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Doença da Mama Fibrocística/reabilitação , Massagem , Mastite/reabilitação , Exercícios de Alongamento Muscular , Adulto , Estudos de Coortes , Feminino , Doença da Mama Fibrocística/fisiopatologia , Humanos , Masculino , Mastite/fisiopatologia , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologiaRESUMO
This novel method of Pedestrian Tracking using Support Vector (PTSV) proposed for a video surveillance instrument combines the Support Vector Machine (SVM) classifier into an optic-flow based tracker. The traditional method using optical flow tracks objects by minimizing an intensity difference function between successive frames, while PTSV tracks objects by maximizing the SVM classification score. As the SVM classifier for object and non-object is pre-trained, there is need only to classify an image block as object or non-object without having to compare the pixel region of the tracked object in the previous frame. To account for large motions between successive frames we build pyramids from the support vectors and use a coarse-to-fine scan in the classification stage. To accelerate the training of SVM, a Sequential Minimal Optimization Method (SMO) is adopted. The results of using a kernel-PTSV for pedestrian tracking from real time video are shown at the end. Comparative experimental results showed that PTSV improves the reliability of tracking compared to that of traditional tracking method using optical flow.
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Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão , Fotografação/métodos , Gravação em Vídeo/métodos , Caminhada/fisiologia , Simulação por Computador , Metodologias Computacionais , Humanos , Sistemas On-Line , Técnica de SubtraçãoRESUMO
Malic enzymes catalyze the reversible oxidative decarboxylation of L-malate using NAD(P)(+) as a cofactor. NADP-dependent malic enzyme (MaeB) from Escherichia coli MG1655 was expressed and purified as a fusion protein. The molecular weight of MaeB was about 83 kDa, as determined by SDS-PAGE. The recombinant MaeB showed a maximum activity at pH 7.8 and 46°C. MaeB activity was dependent on the presence of Mn(2+) but was strongly inhibited by Zn(2+). In order to understand the physiological roles, recombinant E. coli strains (icd (NADP)/ΔmaeB and icd (NAD)/ΔmaeB) containing NADP-dependent isocitrate dehydrogenase (IDH), or engineered NAD-dependent IDH with the deletion of the maeB gene, were constructed using homologous recombination. During growth on acetate, icd (NAD)/ΔmaeB grew poorly, having a growth rate only 60% that of the wild-type strain (icd (NADP)). Furthermore, icd (NADP)/ΔmaeB exhibited a 2-fold greater adaptability to acetate than icd (NAD)/ΔmaeB, which may be explained by more NADPH production for biosynthesis in icd (NADP)/ΔmaeB due to its NADP-dependent IDH. These results indicated that MaeB was important for NADPH production for bacterial growth on acetate. We also observed that MaeB activity was significantly enhanced (7.83-fold) in icd (NAD), which was about 3-fold higher than that in icd (NADP), when switching from glucose to acetate. The marked increase of MaeB activity was probably induced by the shortage of NADPH in icd (NAD). Evidently, MaeB contributed to the NADPH generation needed for bacterial growth on two carbon compounds.