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This work discusses the fabrication of two-dimensional photonic crystal microcavities (PCMs) in a thin GaAs membrane. We have developed a fabrication process for square-lattice, single-hole-defect devices, a class of PCMs that is critically sensitive to fabrication accuracy, demonstrated coupling of InAs quantum dots to the cavity modes, and shown the sensitivity of the emission to the quality of the fabrication process. Reactive ion etching conditions were optimized to produce photonic crystal holes with smooth, straight sidewalls. To achieve, uniform hole sizes throughout the device, we developed a method to correct the proximity effect introduced while defining the photonic crystal holes using electron-beam lithography. Resulting cavities have resonances with quality factors as high as 4000, which proves the quality of our fabrication. (C) 2003 American Vacuum Society.

To improve the performance of laser selective melted 316L stainless steel products, this paper studies the effect of laser power on the mechanical properties. The results of the study showed that when the laser power is 180 W, the surface morphology and tensile fracture of the specimen are best, and the mechanical properties of formed parts can be improved by laser selective melting of 316L stainless steel. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the mechanical properties of three-dimensionally (3D)-printed and conventional surgical plates used for the repair of maxillary or mandibular defects under the same experimental conditions, and to provide experimental evidence for the future application and clinical trial of 3D-printed individualized surgical plates. For the experimental group, two groups of surgical plates with thicknesses of 2.0 mm and 2.5 mm were designed and 3D-printed by electron beam melting, using Ti–6Al–4V as raw material. Conventional commercially available surgical plates with the same thickness were adopted as the control group. A Vickers hardness tester and universal testing machine were used to measure the mechanical properties of the plates (hardness, bending strength, tensile strength, and yield strength). The mechanical properties of 3D-printed surgical plates were significantly better than those of conventional surgical plates of the same thickness (P < 0.001). Comparing the surgical plates of different thickness, the 2.5 mm-thick plates had the highest bending strength in the experimental group (P < 0.001) and the best hardness (P < 0.001), bending strength (P = 0.001), tensile strength (P = 0.001), and yield strength (P = 0.001) in the control group. No statistical difference was found between the two kinds of plates in the experimental group in terms of hardness (P = 0.060), tensile strength (P = 0.096), and yield strength (P = 0.496). The 3D-printed surgical plates have better mechanical properties than the conventional ones. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Dental pulp stem cells (DPSCs) are adult stem cells of neural crest origin, are readily available, have good self-renewal and multidirectional differentiation properties, can differentiate into a variety of cells, are abundant, less harmful to donate, have no ethical issues, low immunogenicity, and therefore, are widely used as seed cells in the field of tissue engineering and regenerative medicine. MicroRNA (miRNA) is a single- stranded non-coding small RNA consisting of about 22 nucleotides, which plays an important regulatory role in various aspects of cellular activities, such as proliferation, differentiation, and apoptosis. In this paper, we review the regulatory role of small RNA in the differentiation of DPSCs and its mechanism in the past 5 years. This paper aims to reveal the important role of miRNAs in differentiation in DPSCs. MATERIALS AND METHODS: MicroRNAs (miRNAs), differentiation, and DPSCs were extensively searched in three databases from 2014 to 2021. These databases include PubMed, Cochrane Library, Embase. RESULTS: Our study reviews the microRNAs (miR-145, miR-143-3p, miR-140-5p, miR-488, miR- 218, miR-125a-3p, miR-27a-5p, miR-223, miR-21, miR-143, miR-215, miR-219a-1-3p, miR-31, miR- 496, miR-218, miR-24-3p, miR-146a-5p, miR-196a, miR-188-3p, miR-424, miR-378a, miR-135, miR- 124) in the differentiation of DPSCs. CONCLUSIONS: A large body of evidence supports the involvement of miRNAs in differentiation associated with mesenchymal stem cells (MSCs), although the mechanisms involved are not yet clear. Most of the current studies are from in vitro studies, but the ultimate goal is to apply these studies to the clinic, and studies involving in vivo models are needed. [ABSTRACT FROM AUTHOR]

Saccharum spontaneum L. is one of the most important germplasm resources for modern sugarcane breeding. Exploring the cold tolerance of S. spontaneum clones with different ploidy levels and screening for cold‐tolerant material can be helpful in parent selection for breeding cold‐tolerant sugarcane.Morphological indices, leaf ultrastructure and physiological indices were used to evaluate the cold tolerance of 36 S. spontaneum clones with different ploidy levels (2n = 40, 48, 54, 60, 64, 78, 80, 88, 92 and 96).The morphological indices of S. spontaneum clones with different ploidy levels were positively correlated with ploidy. Under low‐temperature stress, the chloroplast and mitochondrial structures of the clones with high ploidy were more severely damaged than were those of clones with low ploidy. A comprehensive evaluation of the physiological indices showed that the 36 S. spontaneum clones could be divided into four categories: strongly cold tolerant, cold tolerant, moderately cold tolerant and cold sensitive. Correlation analysis of the morphological indices and cold tolerance revealed a significant negative correlation between cold tolerance and ploidy. On the basis of the morphological and physiological indices, optimal stepwise regression equations that can be used for the selection of cold‐tolerant S. spontaneum resources were established.The S. spontaneum clones with low ploidy are more cold tolerant than those with high ploidy. Clones 12‐37, 13‐10 and 12‐23 are strongly cold‐tolerant germplasm resources, which suggests these germplasm sources have high potential for use in breeding cold‐tolerant sugarcane. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to explore the possible role and mechanism of lncRNA ZEB2-AS1 in the pathogenesis of colon cancer (CCa). PATIENTS AND METHODS: The expression level of ZEB2-AS1 in 41 colon cancer tissue samples and 25 normal tissues was detected by qRTPCR, and appropriate colon cancer cell lines were screened for in vitro experiments. Subcellular localization of ZEB2-AS1 was examined. After ZEB2-AS1 was transfected into colon cancer cells by liposome method, the cell proliferation, migration ability, and cell apoptosis percentage were evaluated by CCK-8 test, transwell assay, and flow cytometry, respectively. In addition, bioinformatics was applied to detect the target genes of microRNA-188. The Luciferase gene reporter assay was then performed to analyze the relative activity of Luciferase between microRNA- 188 and TAB3 or ZEB2-AS1. At the same time, the control sequence, microRNA-188 mimics, microRNA-188 mimics+ ZEB2-AS1, si-TAB3, and microRNA-188 inhibitor+ si-TAB3 were respectively transfected into cells to further verify the interaction between TAB3 and microRNA- 188 or ZEB2-AS1. Besides, the glucose and lactate levels were measured to explore their roles in glycolysis. RESULTS: The expression of ZEB2-AS1 in colon cancer tissues and cells was significantly higher than that in normal ones, and ZEB2-AS1 was confirmed to be mostly located in the cytoplasm. In addition, ZEB2-AS1 overexpression could enhance the cell proliferation rate and migration ability as well as reduce the cell apoptosis, which could be reversed by microRNA-188 overexpression. In addition, bioinformatics prediction and Dual-Luciferase reporter assays revealed that ZEB2-AS1 could bind to microRNA- 188, which could directly target TAB3. At the same time, it was found that the overexpression of ZEB2-AS1 and low expression of microRNA- 188 promoted glycolysis, while the opposite result was observed after overexpression of microRNA- 188 and low expression of TAB3. CONCLUSIONS: The expression of ZEB2-AS1 is significantly increased in colon cancer tissues and cells, which can promote the proliferation, migration, and promote apoptosis of colon cancer cells. It may be involved in the development of this cancer through the process of glycolysis regulated by microRNA-188/TAB3. [ABSTRACT FROM AUTHOR]

Members of the genus Aeromonas are opportunistic pathogen of a variety of aquatic animals that exhibits multidrug resistance, phenotypes, virulence genes and virulence. The present study described the species distribution and the potential pathogenicity of Aeromonas isolated from healthy Northern snakehead (Channa argus) in China. Molecular identification revealed that A. veronii biovar veronii (69/167; 41·3%) and A. hydrophila (41/167; 24·6%) were the most common species found in Northern snakehead intestine based on sequencing of the 16S rRNA gene and DNA gyrase subunit B protein. The distribution of seven virulence factors including aer (84·4%), act (80·8%), ser (40·1%), Aha (27·5%), lip (23·4%), exu (15·0%) and LuxS (12·6%) were determined exclusively in Aeromonas isolates. All the seven virulence genes were present in 9·6% (16/167), among which 11 strains were identified as A. veronii biovar veronii. For the strains harbouring seven virulence genes, the 50% lethal doses (LD50) of isolates were lower compared to the isolates carrying two virulence genes. The challenge tests revealed that isolate W31 had the lowest lethal dose, causing 50% mortality at 4·5 × 103 colony‐forming units (CFU) per ml. Furthermore, histopathology of Northern snakehead infected with Aeromonas strains showed necrosis and congestion in liver, spleen and kidney and also damage to the intestine. This study confirms that the Aeromonas strains isolated from healthy Northern snakehead may be a cause of concern for public health. Significance and Impact of the Study: Aeromonas species are widely distributed in aquatic environments and have considerable virulence potential. The aim of this study was to identify Aeromonas strains isolated from healthy Northern snakehead, and to investigate if Aeromonas species isolated from healthy fish potential pathogenicity with special reference to virulence and epidemiology studies. [ABSTRACT FROM AUTHOR]

4,5‐DOPA dioxygenase (DODA) is a crucial enzyme in the biosynthetic pathway of betalain. Previous studies have shown that DODA is present in plants, fungi and bacteria. Using updated data, here we show that DODA genes (BmDODA) in the domestic silkworm (Bombyx mori) and other lepidopteran insects are most likely to be horizontally transferred from fungi. A synteny analysis indicated that BmDODA1 is orthologous to other lepidopteran DODAs and that BmDODA2 is a paralogous gene. To explore the function of DODA in Lepidoptera, we first examined the expression patterns of BmDODA1. BmDODA1 showed high transcriptional and translational levels in the midgut and head. Then, we exogenously expressed the BmDODA1 gene, detected 4,5‐DOPA ring‐cleaving activity and calculated the kinetic parameters of the recombinant BmDODA1. We found that the transcription levels of BmDODA1 were significantly induced by the pathogens Bacillus bombyseptieus and Escherichia coli. Thus, the horizontal transfer of the BmDODA gene in the silkworm may be involved in dopa metabolism and contribute to antimicrobial activity in this species. Our results provide a documented example of functional horizontal gene transfer (HGT) between fungi and animals and expand our knowledge of HGT amongst eukaryotes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The effects and mechanisms of melatonin on Alzheimer's disease (AD) are still not researched thoroughly. 20E2 cells (HEK293-APPswe cells) are a cellular model of AD. The modulation effects of melatonin on the structure and function of mitochondria in 20E2 cells need to be studied. MATERIALS AND METHODS: The Alzheimer's disease (AD) cell model was assessed for cell viability, expression levels of mitochondrial biogenesis factors (peroxisome proliferator-activated receptor gamma coactivator 1-alpha [PGC-1α], nuclear respiratory factor 1 [NRF1], nuclear respiratory factor 2 [NRF2], mitochondrial transcription factor A [TFAM]), mitochondrial membrane potential, Na+-K+-adenosine triphosphatase (ATPase) and cytochrome C oxidase activity, adenosine triphosphate (ATP) level, mitochondrial DNA/nuclear DNA (mtDNA/nDNA) ratio, and mitochondrial structure with and without melatonin. RESULTS: Melatonin improved 20E2 cell viability, expression of mitochondrial biogenesis factors (PGC-1α, NRF1, NRF2, TFAM), mitochondrial membrane potential, Na+-K+-ATPase, and cytochrome C oxidase activity, ATP level, mtDNA/nDNA ratio, mitochondrial structure, and decreased amyloidogenic amyloid precursor protein processing. CONCLUSIONS: Mitochondrial biogenesis disorder is associated with the pathogenesis of AD through PGC-1α-NRF-TFAM pathway, and melatonin improves the mitochondrial structure and function by enhancing mitochondrial biogenesis and decreasing amyloidogenic APP processing in Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Kotz, C. M., C. F. Wang, J. E. Briggs, A. S. Levine, and C. J. Billington. Effect of NPY in the hypothalamic paraventricular nucleus on uncoupling proteins 1, 2, and 3 in the rat. Am. J. Physiol. Regulatory Integrative Comp. Physiol. 278: R494-R498, 2000.--Neuropeptide Y (NPY) injected into the hypothalamic paraventricular nucleus (PVN) stimulates feeding and decreases uncoupling protein (UCP)-1 mRNA in brown adipose tissue (BAT). The present studies were undertaken to determine whether UCP-2 in white adipose tissue (WAT) and UCP-3 in muscle are regulated by NPY in the PVN. PVN-cannulated male Sprague-Dawley rats were injected with either saline or NPY (PVN, 117 pmol, 0.5 [micro]l) every 6 h for 24 h. NPY in the PVN stimulated feeding and decreased UCP- 1 mRNA in BAT independent of NPY-induced feeding. UCP-2 mRNA in WAT was unchanged by NPY. In acromiotrapezius muscle, NPY decreased UCP-3 mRNA, but this was reversed by restricting food intake to control levels. In biceps femoris muscle, NPY alone had no effect on UCP-3 mRNA, but UCP-3 mRNA was significantly increased in the NPY-treated rats that were restricted to control levels of intake. These results suggest that UCP-2 in WAT and UCP-3 in muscle are not subject to specific regulation by NPY in the PVN. thermogenesis; brown adipose tissue; white adipose tissue; muscle

The study was planned to check the effect of time on dynamics of fermentation, chemical composition and rumen degradation in banana pseudo-stems silage (BPSS). For this purpose banana pseudo-stem (BPS) was ensiled for 0, 20, 30, 40, 50, 60, 70, 80 and 90 days in polyethylene bags. Each time point had three replicates. After 0, 20, 30, 40, 50, 60, 70, 80 and 90 days triplicate polyethylene bags were opened for chemical analysis and fermentation characteristics. Water-soluble carbohydrates (WSC) significantly decreased (19.75±0.53, 7.25±0.09 g kg-1 at day 20 and 30 respectively) after ensiling (P<0.05) but consistency was achieved at 50 day of fermentation to onward. After 50 days of fermentation, crude protein (CP) was increased (52.45±0.63 g kg-1 at day 60) significantly (P<0.05). The pH decreased (P<0.05) at day 30 and consistency was achieved on the subsequent days. Ammonia-nitrogen (NH3-N) showed increasing trend at day 30 and 40 but there was no changing trend on the following days. Lactic acid production was increased (P<0.05) 31.22±0.42and 31.04±0.71 g kg-1 at day 30 and 40 respectively after ensiling and highest lactic acid production was noted at day 80 (51.97±3.09). Only small amounts of butyric acid, isobutyric acid, and propionic acid were detected in the BPS after 50 days. The rumen degradability of banana pseudo-stems (BPS) and BPSS at 80 days of fermentation were studied in sacco in three ruminally cannulated adult Xia'nan cattle (570 ± 23 kg) at 6, 12, 24, 36, 48 and 72 h of incubation periods. The effective degradability (ED) of BPS, neutral detergent fiber (NDF) was higher than that of BPS0. Although the fermentation did not improve ED of DM and CP in BPS, a lower terminal pH, and higher concentration of lactic acid might enhance aerobic stability after opening the silage. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To observe mitophagy in APPsw/PS1dE9 transgenic mice and APPsw stably expressing HEK293 cell. MATERIALS AND METHODS: The APPsw/PS1dE9 transgenic mice and 20E2 cell (HEK293 cell with APPsw) was used to be the model of Alzheimer's disease. We dynamically observed the behavior, mitochondrial structure and mitophagy in brain of APP/PS1 transgenic mice in different age groups. Mitochondrial structure and mitophagy of HEK293 and 20E2 cell in vitro were also recorded. RESULTS: The mitochondrion was changed significantly in APP/PS1 transgenic mice and 20E2 cell. LC3 protein, associated with autophagy, was up-regulated. Mitophagy related protein PINK1 and PARKIN were up-regulated. CONCLUSIONS: Mitophagy disorder may be associated with the pathogenesis of Alzheimer's Disease through PINK1/Parkin pathway. [ABSTRACT FROM AUTHOR]