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排序方式: 共有2076条查询结果,搜索用时 25 毫秒
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Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献
3.
《Ceramics International》2022,48(1):656-664
Formation of p-n junction was an effective method to improve the photocatalytic performance due to its built-in electric field. However, the electric field was distributed only on the interface between two semiconductors, which was insufficient in comparison to the entire material. In this work, a multilayer TiO2–CoTiO3 p-n junction was designed and fabricated by atomic layer deposition. The charge transport and photoelectrochemical properties of multilayer TiO2–CoTiO3 films of various thicknesses are thoroughly investigated. The PL and electrochemical tests demonstrate that TiO2–CoTiO3 exhibits enhanced charge separation and transport. Additionally, the extra visible light response was achieved by introduction of CoTiO3. Also, theoretical calculations indicate that the electrons prefer to immigrate from TiO2 to CoTiO3 in a multilayer TiO2–CoTiO3 structure. Benefited from the boosted light absorption and charge transfer, the multilayer TiO2–CoTiO3 composite film exhibits a significantly increased photocurrent, much higher than pure TiO2 and a single TiO2–CoO p-n junction. This multilayer p-n junction structure opens a rational and novel way for nanostructure construction in the energy conversion region. 相似文献
4.
H.L. Zhu X.W. Zhao R.W. Han Q.J. DU Y.X. Qi H.N. Jiang D.W. Huang Y.X. Yang 《Journal of dairy science》2021,104(8):9263-9275
The newborn gut undergoes rapid colonization by commensal microorganisms and possible exposure to pathogens. The contribution of colostrum intake to host protection is well known; however, limited research exists on the intestinal innate immunity corresponding to colostrum intake during the passive immune transfer period in newborn ruminants. The aim of this study was to investigate the changes in bacterial community and expression of genes encoding toll-like receptors (TLR), mucins (MUC), antimicrobial peptides, and tight junctions in the jejunum of lambs that were fed colostrum during the first 24 h of life. Twenty-seven newborn lambs were used in this study, of which 18 lambs were bottle-fed pooled bovine colostrum within the first 2 h after birth to obtain an intake of approximately 8% of body weight. Lambs were slaughtered at 12 (n = 9) and 24 h (n = 9) after birth. The remaining 9 lambs without any feeding were slaughtered at 30 min after birth (0 h). Tissue and ligated segment samples from the jejunum were collected immediately after the lambs were slaughtered. The bacterial profile in the ligated jejunum segment was assessed using amplicon sequencing. The gene expression in the jejunum tissue was determined using quantitative real-time PCR. The relative abundances of Escherichia-Shigella, Lactobacillus, Lactococcus, and Streptococcus increased, whereas those of Sphingomonas, Phyllobacterium, Bradyrhizobium, and Rudaea decreased during the first 24 h of life. Expression of TLR2 and β-defensin 109-like was upregulated at 12 h after birth, but a recovery was detected at 24 h; TLR3, TLR5, LYZ, MUC1, MUC13, MUC20, and CLDN7 showed a higher expression level in samples taken at 24 h than in those taken at 0 h. In addition, expression level of CLDN1, CLDN4, and the junctional adhesion molecule-1 tended to be higher at 24 h than at 0 h after birth. Correlation analysis indicated that TLR2 expression was negatively correlated with the relative abundance of Lactobacillus and Bradyrhizobium, whereas TLR5 expression was positively correlated with the relative abundance of Escherichia-Shigella and Pelagibacterium. These results suggest that TLR, MUC, antimicrobial peptides, and CLDN act together and play an important role in intestinal defense during the passive immune transfer period. They are potentially associated with microbial colonization. The findings from this study provide novel information to elucidate the role of colostrum components in regulating the development of the intestinal mucosal immune barrier in newborn lambs during the passive immune transfer period. 相似文献
5.
A novel CdS/CaFe2O4 (CS/CFO) heterogeneous p-n junction was created by thermal deposition of CaFe2O4 nanoparticles on CdS rods. The CS/CFO hetero-structured photocatalysts exhibited increasingly efficient visible light harvesting compared to the bare CdS. The CS/CFO composites also presented higher photocurrent and slower decay of photoluminescence, suggesting a better separation of the photo-generated electrons and holes. The photocatalytic H2 evolution quantity on the optimized CS/CFO composite from water in the presence of ethanol was up to 2200 μmol after 3-h visible light illumination, which is more than twice that of the pristine CdS. The chemical interaction between CdS and CaFe2O4 was confirmed by the shifts in the XPS peaks, which made it possible for the charge carriers to transfer across the p-n junction interface. This research highlights the importance of forming an interfacial p-n heterojunction between two semiconductors for efficient charge separation and improved photocatalytic performance. 相似文献
6.
Zhongyuan Fu Xinyi Ma Bing Xia Xiaoyun Hu Jun Fan Enzhou Liu 《International Journal of Hydrogen Energy》2021,46(37):19373-19384
Schottky junction and p-n heterojunction are widely employed to enhance the charge transfer during the photocatalysis process. Herein, Cu and Cu3P co-modified TiO2 nanosheet hybrid (Cu–Cu3P/TiO2) was fabricated using an in situ hydrothermal method. The ternary composite achieved the superior H2 evolution rate of 6915.7 μmol g?1 h?1 under simulated sunlight, which was higher than that of Cu/TiO2 (4643.4 μmol g?1 h?1) and Cu3P/TiO2 (6315.8 μmol g?1 h?1) and pure TiO2 (415.7 μmol g?1 h?1). The enhanced activity can be attributed to the collaboration effect of Schottky junction and p-n heterojunction among Cu/TiO2 and Cu3P/TiO2, which can harvest the visible light, reduce the recombination of charge carriers and lower the overpotential of H2 evolution, leading to a fast H2 evolution kinetics. This work develops a feasible method for the exploration of H2 evolution photocatalyst with outstanding charge separation properties. 相似文献
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8.
Youngseok Lee Cheolmin Park Nagarajan Balaji Youn-Jung Lee Vinh Ai Dao 《Israel journal of chemistry》2015,55(10):1050-1063
Over the past few decades, crystalline silicon solar cells have been extensively studied due to their high efficiency, high reliability, and low cost. In addition, these types of cells lead the industry and account for more than half of the market. For the foreseeable future, Si will still be a critical material for photovoltaic devices in the solar cell industry. In this paper, we discuss key issues, cell concepts, and the status of recent high-efficiency crystalline silicon solar cells. 相似文献
9.
Ultrastructural changes in the cemento‐enamel junction caused by acidic beverages: An in vitro study
Aleksandar D. Mitic Jovanka Z. Gasic Radomir G. Barac Goran S. Radenkovic Slavica M. Sunaric Jelena Z. Popovic Marija M. Nikolic 《Microscopy research and technique》2020,83(2):91-98
The present in vitro study was aimed at evaluating the morphological changes in the cemento‐enamel junction (CEJ) after exposure to acidic beverages using the scanning electron microscopy (SEM). The initial pH and titratable acidity (TA) was analyzed from follow groups: (I) Coca cola, (II) orange juice, (III) Cedevita, (IV) Red Bull, (V) Somersby cider, and (VI) white wine. The CEJ samples (n = 64), obtained from unerupted third molars, were allocated to one control (artificial saliva, n = 16) and six experimental groups (n = 8). The experimental samples were immersed in beverages (50 ml) for 15 min, three times daily, 10 days, and in artificial saliva between immersions. SEM analysis was performed in a blind manner, according to scoring scale. One‐way ANOVA and Tukey's post hoc tests, as well as Kruskal–Wallis and Mann–Whitney U test used for statistical analysis. The pH values of the acidic beverages ranged from 2.65 (Coca cola) to 3.73 (orange juice), and TA ranged from 1.90 ml (Coca cola) to 5.70 ml (orange juice) of NaOH to reach pH 7.0. The SEM analysis indicated statistically significant differences between the control samples and those immersed in acidic beverages. The Groups IV, I, and II, showed the highest CEJ damage grade while those of the Group VI were the lowest. All the tested acidic beverages caused morphological changes in the CEJ with a smaller or larger exposure of dentine surface, and were not always related to the pH or TA of acidic beverages. 相似文献
10.
《International Journal of Hydrogen Energy》2022,47(34):15491-15504
The development of excellent photocatalytic material is highly required for energy and environmental applications. In this study, visible light responsive p-n heterojunction photocatalysts based on CuO/MoO3 with varying ratios of CuO were prepared by the facile hydrothermal method. The crystalline structure, surface morphology, chemical compositions and optical properties of the synthesized photocatalysts were studied using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), photoluminescence (PL) techniques and UV–Vi's absorption spectroscopy. The results showed that the 5%CuO/MoO3 nanocomposite displayed enhanced photocatalytic performance for the production of hydrogen (98.5 μmol h?1g?1) and degradation of dyes rhodamine B (RhB) and alizarine yellow (AY) than all other samples. Furthermore, 5% CuO/MoO3 composite exhibited excellent stability after five consecutive cycles for both RhB and AY dyes. Overall, the improved photocatalytic performance of 5%CuO/MoO3 composite was due to increased adsorption of visible light, good surface morphology, enhanced charge separation/transfer which inhibited recombination of electrons and holes. This study could encourage the synthesis of novel and effective p-n heterojunction photocatalysts for practical applications. 相似文献