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1.
Opt Express ; 30(8): 12397-12408, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35472876

RESUMEN

An ultra-compact fiber inline Mach-Zehnder interferometer sensor based on femtosecond laser micromachining technology is demonstrated. It is found that the microstructure has an ultra-high refractive index sensitivity of 16660 nm/RIU when a femtosecond pulsed laser is used to remove the upper cladding and part of the core of a standard single-mode fiber. However, its temperature sensitivity is not much different from that of most pure quartz fibers and can be as high as 7.934 nm/°C when the microcavity is coated with a low-refractive-index ultraviolet adhesive, which was originally used for bonding glass. With this coating, however, it demonstrates excellent robustness.

2.
Micromachines (Basel) ; 15(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38258220

RESUMEN

In this paper, the degradation behaviors of the ferroelectric gate Gallium nitride (GaN) high electron mobility transistor (HEMT) under positive gate bias stress are discussed. Devices with a gate dielectric that consists of pure Pb(Zr,Ti)O3 (PZT) and a composite PZT/Al2O3 bilayer are studied. Two different mechanisms, charge trapping and generation of traps, both contribute to the degradation. We have observed positive threshold voltage shift in both kinds of devices under positive gate bias stress. In the devices with a PZT gate oxide, we have found the degradation is owing to electron trapping in pre-existing oxide traps. However, the degradation is caused by electron trapping in pre-existing oxide traps and the generation of traps for the devices with a composite PZT/Al2O3 gate oxide. Owing to the large difference in dielectric constants between PZT and Al2O3, the strong electric field in the Al2O3 interlayer makes PZT/Al2O3 GaN HEMT easier to degrade. In addition, the ferroelectricity in PZT enhances the electric field in Al2O3 interlayer and leads to more severe degradation. According to this study, it is worth noting that the reliability problem of the ferroelectric gate GaN HEMT may be more severe than the conventional metal-insulator-semiconductor HEMT (MIS-HEMT).

3.
J Colloid Interface Sci ; 664: 882-892, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38493653

RESUMEN

The active cyano-group in polyacrylonitrile has severe passivation of lithium anode under larger current density, which restricts the wide application of polyacrylonitrile(PAN) in lithium metal batteries. Herein, in order to address the excessive passivation of lithium metal by PAN, inspired by the pre-oxidation of carbon fibers, PAN was pre-oxidized at 230 °C, which transformed part of the cyano group into a more chemically stable cyclized structure. The electrochemical and mechanical properties of the composite solid electrolyte were effectively improved by introducing the fast ionic conductor Li6.25La3Zr2Al0.25O12 into PAN by electrospinning. The oxidized PAN-based composite solid electrolyte presents high ionic conductivity (3.05 × 10-3 S·cm-1) and high lithium transference number of 0.79 at 25 °C, further contributing to a high electrochemical window (5.3 V). The solid-state batteries assembled by Li||10 wt%-LLZAO@230-oxy-PAN||NCM523 behave superb electrochemical performance, delivering a high initial discharge capacity of 157 mAh g-1 at 0.2 C. After 100 cycles, the capacity retention was 93.3 %, indicating the electrolyte displays great electrochemical stability. This work provides new insights into the structural design of polymer-based high-voltage batteries.

4.
J Dent Sci ; 18(1): 282-294, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36643258

RESUMEN

Background/purpose: Circular RNAs (circRNAs) have been identified as potential functional modulators of the cellular physiology processes. This study aims to learn the potential molecular mechanisms of hsa_circ_0005050 (circ_0005050) in oral squamous cell carcinoma (OSCC). Materials and methods: Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was used to examine the expression of circ_0005050, miR-487a-3p, and chondroitin sulfate synthase 1 (CHSY1). Dual-luciferase reporter system, RNA pull-down, and RNA Immunoprecipitation (RIP) assays were used to determine the binding between miR-487a-3p and circ_0005050 or CHSY1. Colony formation experiment and EdU assay were used to investigate proliferation. Wound-healing and transwell assays were used to detect the migration of cells. The apoptosis rate of OSCC cells was tested by flow cytometry. Protein levels of related factors were determined by Western blot. Tumor xenograft was established to determine the regulatory role of circ_0005050 on tumor growth in vivo, and Ki-67 expression was detected in this xenograft using Immunohistochemical (IHC). Results: We implicated that circ_0005050 was apparently upregulated in OSCC tissues cells. In function experiments, repressing of circ_0005050 remarkably retarded OSCC growth in vitro. Furthermore, we conducted dual-luciferase reporter assays and RNA pull-down assays to verify that circ_0005050 sponged miR-487a-3p. Suppression of miR-487a-3p rescued the inhibition of proliferation in SCC15 and SCC25 cells induced by circ_0005050 knockdown. In addition, we found that overexpression of CHSY1 also reversed the inhibitory effect of circ_0005050 silencing on cell proliferation. Moreover, circ_0005050 knockdown inhibited tumor growth in vivo. Conclusion: Circ_0005050 acted as an oncogenic factor in OSCC progression through miR-487a-3p/CHSY1 axis.

5.
Materials (Basel) ; 16(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37110000

RESUMEN

This study proposed an all-fiber Fabry-Perot interferometer (FPI) strain sensor with two miniature bubble cavities. The device was fabricated by writing two axial, mutually close short-line structures via femtosecond laser pulse illumination to induce a refractive index modified area in the core of a single-mode fiber (SMF). Subsequently, the gap between the two short lines was discharged with a fusion splicer, resulting in the formation of two adjacent bubbles simultaneously in a standard SMF. When measured directly, the strain sensitivity of dual air cavities is 2.4 pm/µÎµ, the same as that of a single bubble. The measurement range for a single bubble is 802.14 µÎµ, while the measurement range for a double bubble is 1734.15 µÎµ. Analysis of the envelope shows that the device possesses a strain sensitivity of up to 32.3 pm/µÎµ, which is 13.5 times higher than that of a single air cavity. Moreover, with a maximum temperature sensitivity of only 0.91 pm/°C, the temperature cross sensitivity could be neglected. As the device is based on the internal structure inside the optical fiber, its robustness could be guarantee. The device is simple to prepare, highly sensitive, and has wide application prospects in the field of strain measurement.

6.
Microbiol Spectr ; 11(6): e0032723, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37929993

RESUMEN

IMPORTANCE: In in vitro studies, it has been found that the effects of MLT on rumen microorganisms and metabolites can change the rumen flora structure, significantly inhibit the relative abundance of harmful Acinetobacter, and improve the relative abundance of beneficial bacteria. MLT may regulate the "arginine-glutathione" pathway, "phenylalanine, tyrosine and tryptophan biosynthesis-tryptophan generation" branch, "tryptophan-kynurenine" metabolism, and "tryptophan-tryptamine-serotonin" pathway through microorganisms.


Asunto(s)
Microbioma Gastrointestinal , Melatonina , Animales , Triptófano/metabolismo , Melatonina/metabolismo , Rumen , Redes y Vías Metabólicas
7.
Animals (Basel) ; 13(22)2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38003112

RESUMEN

Glucose and amino acids are important sources of nutrients in the synthetic milk of dairy cows, and understanding the fate of amino acids is essential to optimize the utilization of amino acids in milk protein synthesis, thereby reducing nutrient inefficiencies during lactation. The purpose of this study was to investigate the effects of LPS and different concentrations of glucose on (1) the expression of inflammatory factors and genes, (2) the glucose metabolism, and (3) amino acid utilization in BMECs. The results showed that there was an interaction (LPS × glucose, p < 0.05) between LPS and glucose content in the inflammatory cytokine genes (IL-6 and TNF-α) and the inflammatory regulatory genes (CXCL2, CXCL8, and CCL5). With the addition of LPS, the HG + LPS group caused downregulated (p < 0.05) expression of IL-6 and TNF-α, compared with the LG + LPS group. Interestingly, compared with the LG + LPS group, the HG + LPS group upregulated (p < 0.05) the expression of CXCL2, CXCL8, and CCL5. LPS supplementation increased (p = 0.056) the consumption of glucose and GLUT1 gene expression (p < 0.05) and tended to increase (p = 0.084) the LDHA gene expression of BMECs under conditions of different concentrations of glucose culture. High glucose content increased (p < 0.001) the consumption of glucose and enhanced (p < 0.05) the GLUT1, HK1, HK2, and LDHA gene expression of BMECs with or without LPS incubation, and there was an interaction (LPS × glucose, p < 0.05) between LPS and glucose concentrations in GLUT1 gene expression. In this study, LPS enhanced (p < 0.05) the consumption of amino acids such as tryptophan, leucine, isoleucine, methionine, valine, histidine, and glutamate, while high levels of glucose decreased (p < 0.01) consumption, except in the case of tyrosine. For histidine, leucine, isoleucine, and valine consumption, there was an interaction (LPS × glucose, p < 0.05) between LPS and glucose levels. Overall, these findings suggest that relatively high glucose concentrations may lessen the LPS-induced BMEC inflammatory response and reduce amino acid consumption, while low glucose concentrations may increase the demand for most amino acids through proinflammatory responses.

8.
Antioxidants (Basel) ; 12(12)2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38136218

RESUMEN

Manipulating dietary nutrients, especially protein fractions, holds significance in enhancing the antioxidant capacity and immunity function of ruminants. This study investigated the impact of dietary adjustments in soluble protein (SP) levels, in conjunction with a reduction in crude protein (CP) content, on the antioxidant capacity, inflammatory response, carcass characteristics, and meat quality of sheep. This study had four dietary treatments, including a control diet (CON) adhering to NRC standards with a CP content of 16.7% on a dry matter basis and three diets with an approximately 10% reduction in CP content compared to CON with SP levels (% of CP) of 21.2 (SPA), 25.9 (SPB) and 29.4% (SPC), respectively. Thirty-two healthy male Hu sheep, with an initial live weight of 40.37 ± 1.18 kg and age of 6 months, were randomly divided into four groups to receive these respective diets. Our data revealed no significant differences in slaughter performance among treatments (p > 0.05), although low-protein treatments decreased the stomachus compositus index (p < 0.05). Compared with CON, as SP was adjusted to 21.2%, total antioxidant capacity (T-AOC) and catalase (CAT) concentrations were decreased in the serum (p < 0.05), glutathione peroxidase (GSH-Px) content was decreased in jejunum and ileum (p < 0.05), superoxide dismutase (SOD) concentration was reduced in the duodenum (p < 0.05), and malondialdehyde (MDA) content was increased in spleen and ileum (p < 0.05). On the other hand, pro-inflammatory cytokine (IL-1ß, IL-6 and IL-8) contents were upregulated in the serum (p < 0.05), while immunoglobulin (IgA and IgM) contents were reduced in the duodenum (p < 0.05) with SP adjustments. Additionally, the SPB and SPC diets reduced the content of saturated fatty acids and increased the content of polyunsaturated fatty acids compared with CON (p < 0.05), along with retention in the tenderness and water-holding capacity of the longissimus lumborum muscle. In summary, reducing CP by 10% with an SP proportion of ~25-30% improved meat quality without compromising antioxidant capacity and immunity function, while lower SP levels had adverse effects.

9.
Oxid Med Cell Longev ; 2022: 2109891, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35401922

RESUMEN

Evidence reveals that propofol protects cells via suppressing excessive autophagy induced by hypoxia/reoxygenation (H/R). Previously, we found in a genome-wide microRNA profile analysis that several autophagy-related microRNAs were significantly altered during the process of H/R in the presence or absence of propofol posthypoxia treatment (P-PostH), but how these microRNAs work in P-PostH is still largely unknown. Here, we found that one of these microRNAs, microRNA-30b (miR-30b), in human umbilical vein endothelial cells (HUVECs) was downregulated by H/R treatment but significantly upregulated by 100 M propofol after H/R treatment. miR-30b showed similar changes in open heart surgery patients. By dual-luciferase assay, we found that Beclin-1 is the direct target of miR-30b. This conclusion was also supported by knockdown or overexpression of miR-30b. Further studies showed that miR-30b inhibited H/R-induced autophagy activation. Overexpression or knockdown of miR-30b regulated autophagy-related protein gene expression in vitro. To clarify the specific role of propofol in the inhibition of autophagy and distinguish the induction of autophagy from the damage of autophagy flux, we used bafilomycin A1. LC3-II levels were decreased in the group treated with propofol combined with bafilomycin A1 compared with the group treated with bafilomycin A1 alone after hypoxia and reoxygenation. Moreover, HUVECs transfected with Ad-mCherry-GFP-LC3b confirmed the inhibitory effect of miR-30b on autophagy flux. Finally, we found that miR-30b is able to increase the cellular viability under the H/R condition, partially mimicking the protective effect of propofol which suppressed autophagy via enhancing miR-30b and targeting Beclin-1. Therefore, we concluded that propofol upregulates miR-30b to repress excessive autophagy via targeting Beclin-1 under H/R condition. Thus, our results revealed a novel mechanism of the protective role of propofol during anesthesia. Clinical Trial Registration Number. This trial is registered with ChiCTR-IPR-14005470. The name of the trial register: Propofol Upregulates MicroRNA-30b to Repress Beclin-1 and Inhibits Excessive Autophagy and Apoptosis.


Asunto(s)
MicroARNs , Propofol , Daño por Reperfusión , Apoptosis , Autofagia/genética , Beclina-1/genética , Beclina-1/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Hipoxia , Isquemia , MicroARNs/metabolismo , Propofol/farmacología , Propofol/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo
10.
Front Microbiol ; 13: 978940, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36090065

RESUMEN

Silage is rich in nutrients, which can make up for the lack of seasonal roughage, and has a certain promotion effect on the intensive feeding of ruminants. In addition, silage can maintain the rumen function of ruminants to a certain extent and reduce the risk of rumen acidosis and abomasum translocation. The purpose of this study was to investigate the effects of the mixed silage of Chinese cabbage waste and rice straw (mixed silage) on antioxidant performance, rumen microbial population, and fermentation metabolism of Hu sheep. The 16 healthy Hu sheep (eight rams and eight ewes, 39.11 ± 1.16 kg, 5.5 months) were randomly divided into two groups (the control group and the mixed silage group) with eight animals (four rams and four ewes) in each group. The control group was fed with farm roughage (peanut seedlings, corn husk, and high grain shell) as forage, and the mixed silage group was fed with the mixed silage as forage. The results showed that the mixed silage had no effect on the growth performance of Hu sheep (p > 0.05). Ruminal butyric acid, total volatile fatty acids (TVFA), and ammonia nitrogen (NH3-N) concentration in the mixed silage group were increased, whereas the pH was decreased (p < 0.05). The blood and rumen total antioxidants capacity (T-AOC) concentration in the mixed silage group was higher, and the malondialdehyde (MDA) content in rumen, serum, liver, and kidney was lower than that in the control group (p < 0.05). PCoA and ANOSIM results of Illumina sequencing indicated that the mixed silage affected the bacterial composition of the rumen microbes. The mixed silage increased the proportion of Prevotellaceae UCG-004 which was in a positive correlation with Vitamin C (Vc). In addition, PICRUSt functional prediction analysis showed that ascorbate and aldarate metabolism were up-regulated in the mixed silage group (p < 0.05). In conclusion, higher contents of VC and acid detergent fiber (ADF) in the mixed silage were beneficial to the growth and reproduction of Prevotellaceae UCG-004, resulting in increased production of the butyric acid significantly upregulated the metabolism of ascorbate and aldarate metabolism, thereby improving the antioxidant properties of Hu sheep.

11.
Front Nutr ; 8: 815358, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35118112

RESUMEN

Ruminants account for a relatively large share of global nitrogen (N) emissions. It has been reported that nutrition control and precise feeding can improve the N efficiency of ruminants. The objective of the study was to determine the effects of soluble protein (SP) levels in low-protein diets on growth performance, nutrient digestibility, rumen microbiota, and metabolites, as well as their associations of N metabolism in fattening Hu sheep. Approximately 6-month-old, 32 healthy fattening male Hu sheep with similar genetic merit and an initial body weight of 40.37 ± 1.18 kg were selected, and divided into four groups (n = 8) using the following completely randomized design: the control diet (CON) with a 16.7% crude protein (CP) content was prepared to meet the nutritional requirements of fattening sheep [body weight (BW): 40 kg, average daily gain (ADG): 200-250 g/d] according to the NRC recommendations; other three include low protein diets (LPA, LPB, and LPC) of CP decreased by ~10%, with SP proportion (%CP) of 21.2, 25.9, and 29.4 respectively. The feeding trial lasted for 5 weeks including the first week of adaptation. The results showed no difference in the growth performance (P > 0.05); DM and CP digestibility were higher in LPB and LPC, with maximum organic matter digestibility in LPB (P < 0.05). Low-protein diets decreased serum urea-N whereas urinary urea-N was lower in LPB and LPC (P < 0.05), while N retention and the biological value of N were higher in LPB and LPC (P < 0.05). Ruminal NH3-N concentration in LPA and LPB was low than CON (P < 0.05), while total volatile fatty acid (TVFA), acetate, propionate, and butanoate were all lowest in LPA (P < 0.05). In the rumen microbiome, LPB increased the community richness in Prevotellaceae and Prevotella_1 (P < 0.05); Metabolomics analysis revealed low-protein diets downregulated the amino acid metabolism pathways, while the biosynthesis of unsaturated fatty acids along with vitamin B6 metabolism were upregulated with increased SP. These findings could help us understand the role of different SP levels in the regulation of rumen microbial metabolism and N efficiency. Overall, low-protein diets (CP decreased by ~10%) can reduce serum urea-N and ruminal NH3-N without affecting the growth performance of fattening Hu sheep. Additionally higher N efficiency was obtained with an SP proportion of ~25-30%.

12.
Eur J Pharmacol ; 833: 69-78, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29807030

RESUMEN

Ischemia-reperfusion injury(IRI), described as tissue damage caused by reversible ischemic injury or hypoxia prior to the blood supply restoration, is a common pathological phenomenon. In recent study, a hypoxia-reoxygenation (H/R) in the presence or absence of propofol posthypoxia treatment (P-PostH) cell model was built to simulate the condition of IRI, and researchers found propofol may protect cells by suppressing autophagic cell death. To investigate the mechanism underling the protective effect of propofol. A metabolomic analysis was performed in this study using ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF- MS) to compare the metabolism during the process of H/R in the presence or absence of P-PostH. A total of 22 metabolites were detected varied after propofol posthypoxia treatment. Pathway analysis revealed these metabolites were mainly involved in the purine metabolic pathway, three carboxylic acid metabolic pathways, alanine, aspartate and glutamate metabolism pathway and lipid metabolism pathway. We measured the level of Hypoxanthine to verify the metabolomics work, for pathway analysis, we detect the level of reactive oxygen species with H/R and P-PostH treatment. Our study achieved a global comparison of metabolism profiling of H/R cell model with or without propofol posthypoxic treatment. The result indicated that propofol can attenuate endothelial injury caused by IRI by reducing oxidative damage.


Asunto(s)
Anestésicos Intravenosos/farmacología , Hipoxia de la Célula/efectos de los fármacos , Hipnóticos y Sedantes/farmacología , Propofol/farmacología , Daño por Reperfusión/prevención & control , Supervivencia Celular , Células Cultivadas , Cromatografía Líquida de Alta Presión , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Hipoxantina/metabolismo , Metabolómica , Especies Reactivas de Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Espectrometría de Masas en Tándem , Xantina/metabolismo
13.
Oxid Med Cell Longev ; 2013: 378484, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24454982

RESUMEN

Recent studies indicate that propofol may protect cells via suppressing autophagic cell death caused by excessive reactive oxygen species induced by hypoxia reoxygenation (H/R). It is established that gene expression patterns including autophagy-related genes changed significantly during the process of H/R in the presence or absence of propofol posthypoxia treatment (P-PostH). The reasons for such differences, however, remain largely unknown. MicroRNAs provide a novel mechanism for gene regulation. In the present study, we systematically analyzed the alterations in microRNA expression using human umbilical vein endothelial cells (HUVECs) subjected to H/R in the presence or absence of posthypoxic propofol treatment. Genome-wide profiling of microRNAs was then conducted using microRNA microarray. Fourteen miRNAs are differentially expressed and six of them were validated by the quantitative real-time PCR (Q-PCR) of which three were substantially increased, whereas one was decreased. To gain an unbiased global perspective on subsequent regulation by altered miRNAs, predicted targets of ten miRNAs were analyzed using the Gene Ontology (GO) analysis to build signaling networks. Interestingly, six of the identified microRNAs are known to target autophagy-related genes. In conclusion, our results revealed that different miRNA expression patterns are induced by propofol posthypoxia treatment in H/R and the alterations in miRNA expression patterns are implicated in regulating distinctive autophagy-related gene expression.


Asunto(s)
Autofagia/genética , Perfilación de la Expresión Génica , MicroARNs/genética , Modelos Biológicos , Oxígeno/farmacología , Propofol/farmacología , Transducción de Señal/genética , Autofagia/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Regulación de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes , Células Endoteliales de la Vena Umbilical Humana , Humanos , MicroARNs/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Reproducibilidad de los Resultados , Transducción de Señal/efectos de los fármacos
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