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1.
Microsyst Nanoeng ; 9: 108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654693

RESUMO

Electrothermal bimorph-based scanning micromirrors typically employ standard silicon dioxide (SiO2) as the electrothermal isolation material. However, due to the brittle nature of SiO2, such micromirrors may be incapable to survive even slight collisions, which greatly limits their application range. To improve the robustness of electrothermal micromirrors, a polymer material is incorporated and partially replaces SiO2 as the electrothermal isolation and anchor material. In particular, photosensitive polyimide (PSPI) is used, which also simplifies the fabrication process. Here, PSPI-based electrothermal micromirrors have been designed, fabricated, and tested. The PSPI-type micromirrors achieved an optical scan angle of ±19.6° and a vertical displacement of 370 µm at only 4 Vdc. With a mirror aperture size of 1 mm × 1 mm, the PSPI-type micromirrors survived over 200 g accelerations from either vertical or lateral directions in impact experiments. In the drop test, the PSPI-type micromirrors survived falls to a hard floor from heights up to 21 cm. In the standard frequency sweeping vibration test, the PSPI-type micromirrors survived 21 g and 29 g acceleration in the vertical and lateral vibrations, respectively. In all these tests, the PSPI-type micromirrors demonstrated at least 4 times better robustness than SiO2-type micromirrors fabricated in the same batch.

2.
Vet Microbiol ; 274: 109555, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36095877

RESUMO

Japanese encephalitis virus (JEV) is a major causative agent of neurological infection affecting humans and pigs. Human T Cell Immunoglobulin and Mucin Domain 1 (hTIM-1) enhances the infection of JEV through virion-associated phosphatidylserine (PS) binding. Here, five swine TIM-1 (sTIM-1) gene variants were cloned from pig lung tissues by reverse-transcriptase polymerase chain reaction (RT-PCR). Sequence alignment analysis revealed that the gene homology between the sTIM-1 and hTIM-1 was 42.3-43.8%. Furthermore, ectopic expression of all five sTIM-1 variants in 293 T cells can promote JEV entry and infection. However, sTIM-1 V3 exhibited significantly less potent at promoting virus entry compared to the other four variants. Further studies revealed that the 34th amino acid of sTIM-1is critical for the entry of JEV, which is Pro34 in sTIM-1V3 while Leu34 in other four sTIM-1 variants. Mechanically, leucine at locus 34 was associated with the membrane distribution of sTIM-1, thereby affecting viral entry and infection. In total, our findings provide evidence that the PS receptor sTIM-1 promotes the infection of JEV and that the 34th amino acid position is critical for sTIM-1 to mediate viral infection.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Suínos , Animais , Humanos , Vírus da Encefalite Japonesa (Espécie)/genética , Fosfatidilserinas , Leucina/genética , Encefalite Japonesa/veterinária , Mutação , Imunoglobulinas , Mucinas/genética
3.
Ecotoxicol Environ Saf ; 242: 113915, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901591

RESUMO

Rainbow trout (Oncorhynchus mykiss) is a typical cold-water aquaculture fish and a high-end aquatic product. When water temperature exceeds its optimal range of 12-18 °C, the immune system of rainbow trout becomes weakened and unbalanced. High temperature in summer and global warming severely impact rainbow trout industry. The focus of this study was to explore the mechanisms regulating the immune response of rainbow trout under high temperature stress and identify molecular elements that account for resistance to high temperature. In this study, individual fish were screened in a high temperature stress experiment and divided into resistant (R) and sensitive (S) groups. The hepatic transcriptome sequencing and analysis of mRNAs and microRNAs of the R, S, and control groups showed that the number of the differentially expressed genes (DEGs) in the S group (9259) was higher than that in the R group (5313). Furthermore, the 1233 genes differentially expressed between S and R groups were mainly enriched in immune-related pathways, including cytokine-cytokine receptor interaction, TNF signaling and IL-17 signaling. Among these DEGs were miR-301b-5p and its target gene that encodes nuclear factor of activated T cells two interacting protein (nfatc2ip). The dual-luciferase reporter system and immunofluorescence experiments verified the relationship between miR-301b-5p and nfatc2ip. We also showed that expression levels of miR-301b-5p and nfatc2ip significantly negatively correlated in the liver of rainbow trout under high temperature stress. By performing functional experiments, we showed that activation of miR-301b-5p expression or inhibition of nfatc2ip expression stimulated the phosphorylation of p65, p38, and JNK in the classical nuclear factor kappa-B and mitogen-activated protein kinase pathways under high temperature stress. These manipulations initially promoted the secretion of the pro-inflammatory factor IL-1ß and then increased the levels of IL-6, IL-12, and TNF-α. In addition, activation of miR-301b-5p expression or inhibition of nfatc2ip expression stimulated the repair of the hepatic ultrastructural damage caused by high temperature stress by activating the inflammatory response in rainbow trout liver.


Assuntos
MicroRNAs , Oncorhynchus mykiss , Animais , Fígado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Oncorhynchus mykiss/fisiologia , Temperatura , Água/metabolismo
4.
Front Vet Sci ; 9: 752521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252414

RESUMO

Brachymystax lenok (lenok) is a rare cold-water fish native to China that is of high meat quality. Its wild population has declined sharply in recent years, and therefore, exploring the molecular mechanisms underlying the development and reproduction of lenoks for the purposes of artificial breeding and genetic improvement is necessary. The lenok comparative transcriptome was analyzed by combining single molecule, real-time, and next generation sequencing (NGS) technology. Differentially expressed genes (DEGs) were identified in five tissues (head kidney, spleen, liver, muscle, and gonad) between immature [300 days post-hatching (dph)] and mature [three years post-hatching (ph)] lenoks. In total, 234,124 and 229,008 full-length non-chimeric reads were obtained from the immature and mature sequencing data, respectively. After NGS correction, 61,405 and 59,372 non-redundant transcripts were obtained for the expression level and pathway enrichment analyses, respectively. Compared with the mature group, 719 genes with significantly increased expression and 1,727 genes with significantly decreased expression in all five tissues were found in the immature group. Furthermore, DEGs and pathways involved in the endocrine system and gonadal development were identified, and p38 mitogen-activated protein kinases (MAPKs) were identified as potentially regulating gonadal development in lenok. Inhibiting the activity of p38 MAPKs resulted in abnormal levels of gonadotropin-releasing hormone, follicle-stimulating hormone, and estradiol, and affected follicular development. The full-length transcriptome data obtained in this study may provide a valuable reference for the study of gene function, gene expression, and evolutionary relationships in B. lenok and may illustrate the basic regulatory mechanism of ovarian development in teleosts.

5.
Fish Shellfish Immunol ; 122: 78-86, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35051564

RESUMO

Antimicrobial peptides are immune system molecules existing in different organisms including mollusks, crustaceans and vertebrates. Hepcidins are a group of cysteine rich antimicrobial peptides, which plays an important role in fish response to a variety of pathogens. In this study, we cloned and identified Hepcidin from the Coregonus ussuriensis Berg, and its functions in vivo and in vitro was investigated. Our results showed that, CuHepc contains a 267 bp coding sequence (CDS) region that encodes 88 putative amino acids with a molecular weight of 9.77 kD. Hepcidin transcripts were most abundant in the liver of healthy C. ussuriensis Berg. The synthesized Hepcidin peptide exhibited a wide range of antibacterial activity against Gram-positive and Gram-negative bacteria in vitro, and the results of in vivo bacterial attack assays showed that the CuHepc gene was differentially up-regulated in the six tissues investigated after infection with Aeromonas hydrophila. To analyze the changes in protein levels in C. ussuriensis, we generated Hepc polyclonal antibodies in rabbits and verified that the protein expression was increased after bacterial infection with Western blot assay. MIC assay results showed a geometric mean value of 5.513 µM for CuHepc peptide. In the in vivo experiment, immune-related genes IL-10, NF-κB, TLR3 were up-regulated post-infection CuHepc peptide in liver and intestine. Finally, CuHepc peptide reduced the tissues microbial load compared to infection with Aeromonas hydrophila. The above results indicate that Hepc plays a role in the immune response of C. ussuriensis to exogenous disturbances, indicate that CuHepc might act a candidate for modulation of the innate immune system in C. ussuriensis.


Assuntos
Doenças dos Peixes , Salmonidae , Sequência de Aminoácidos , Animais , Antibacterianos , Peptídeos Antimicrobianos , Proteínas de Peixes/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Hepcidinas/química , Filogenia , Coelhos
6.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4015-4016, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25629501

RESUMO

The complete mitochondrial DNA sequence of Gymnocypris chilianensis was determined and analyzed. The mitogenome of G. chilianensis is 16,667 bp long, containing 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 2 non-coding regions: control region (D-loop) and origin of light-strand replication (OL). The gene order of mitogenome is identical to that observed in most other vertebrates. The complete mitogenome sequence information of G. chilianensis can provide useful data for further studies on molecular systematic, taxonomic status, stock evaluation and conservation genetics.


Assuntos
Cipriniformes/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Animais , Origem de Replicação
7.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4106-4107, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26065846

RESUMO

In this study, we determined the complete mitochondrial genome sequence of Schizothorax davidi. The length of the genome is 16,577 bp, which contains 13 protein coding genes, 22 transfer RNAs, two ribosomal RNAs, and two non-coding regions: control region (D-loop) and origin of light-strand replication (OL). The complete mitochondrial DNA sequence of S. davidi provides useful genetic markers for the studies on molecular systematic, population genetics, and phylogeography.


Assuntos
Cyprinidae/genética , Cipriniformes/genética , Genoma Mitocondrial/genética , Mitocôndrias/genética , Animais , DNA Mitocondrial/genética , Ordem dos Genes/genética , Marcadores Genéticos/genética , Genética Populacional/métodos , Filogeografia/métodos , RNA Ribossômico/genética , RNA de Transferência/genética , RNA não Traduzido/genética , Análise de Sequência de DNA/métodos , Sequenciamento Completo do Genoma/métodos
8.
Sensors (Basel) ; 10(4): 4130-44, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22319346

RESUMO

A novel design of a microelectromechanical systems (MEMS) control moment gyroscope (MCMG) was proposed in this paper in order to generate a torque output with a magnitude of 10(-6) N·m. The MCMG consists of two orthogonal angular vibration systems, i.e., the rotor and gimbal; the coupling between which is based on the Coriolis effect and will cause a torque output in the direction perpendicular to the two vibrations. The angular rotor vibration was excited by the in-plane electrostatic rotary comb actuators, while the angular gimbal vibration was driven by an out-of-plane electrostatic parallel plate actuator. A possible process flow to fabricate the structure was proposed and discussed step by step. Furthermore, an array configuration using four MCMGs as an effective element, in which the torque was generated with a phase difference of 90 degrees between every two MCMGs, was proposed to smooth the inherent fluctuation of the torque output for a vibrational MCMG. The parasitic torque was cancelled by two opposite MCMGs with a phase difference of 180 degrees. The designed MCMG was about 1.1 cm×1.1 cm×0.04 cm in size and 0.1 g in weight. The simulation results showed that the maximum torque output of a MCMG, the resonant frequency of which was approximately 1,000 Hz, was about 2.5×10(-8) N·m. The element with four MCMGs could generate a torque of 5×10(-8) N·m. The torque output could reach a magnitude of 10(-6) N·m when the frequency was improved from 1,000 Hz to 10,000 Hz. Using arrays of 4×4 effective elements on a 1 kg spacecraft with a standard form factor of 10 cm×10 cm×10 cm, a 10 degrees attitude change could be achieved in 26.96 s.

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