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1.
Hum Mol Genet ; 32(14): 2326-2334, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37133443

RESUMO

Fertilization is a fundamental process of development, and the blocking mechanisms act at the zona pellucida (ZP) and plasma membrane of the egg to prevent any additional sperm from binding, permeating and fusing after fertilization. In clinical practice, some couples undergoing recurrent IVF failures that mature oocytes had abnormal fertilization for unknown reason. Ovastacin encoded by ASTL cleave the ZP protein ZP2 and play a key role in preventing polyspermy. Here, we identified bi-allelic variants in ASTL that are mainly characterized by fertilization problems in humans. All four independent affected individuals had bi-allelic frameshift variants or predicted damaging missense variants, which follow a Mendelian recessive inheritance pattern. The frameshift variants significantly decreased the quantity of ASTL protein in vitro. And all missense variants affected the enzymatic activity that cleaves ZP2 in mouse egg in vitro. Three knock-in female mice (corresponding to three missense variants in patients) all show subfertility due to low embryo developmental potential. This work presents strong evidence that pathogenic variants in ASTL cause female infertility and provides a new genetic marker for the diagnosis of fertilization problems.


Assuntos
Infertilidade Feminina , Sêmen , Humanos , Masculino , Feminino , Camundongos , Animais , Glicoproteínas da Zona Pelúcida/genética , Glicoproteínas da Zona Pelúcida/metabolismo , Sêmen/metabolismo , Oócitos/metabolismo , Infertilidade Feminina/genética , Fertilização/genética , Metaloproteases/genética
2.
J Immunol ; 211(7): 1154-1166, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37610222

RESUMO

Chronic graft-versus-host disease (cGVHD) involves multiple organs, but little is known about bone marrow (BM) alterations caused by cGVHD. In mice and humans, we found that cGVHD is associated with BM fibrosis resulting in T cell infiltration, IgG deposition, and hematopoietic dysfunction. Macrophages and Nestin+ mesenchymal stromal cells (MSCs) participated in the process of BM fibrosis during BM cGVHD development. BM macrophage numbers were significantly increased in mice and humans with BM fibrosis associated with cGVHD. Amplified macrophages produced TGF-ß1, which recruited Nestin+ MSCs forming clusters, and Nestin+ MSCs later differentiated into fibroblasts, a process mediated by increased TGF-ß/Smad signaling. TLR4/MyD88-mediated activation of endoplasmic reticulum (ER) stress in macrophages is associated with fibrosis by increasing Nestin+ MSC migration and differentiation into fibroblasts. Depletion of macrophages by clodronate-containing liposomes and inhibition of ER stress by 4-phenylbutyric acid reversed BM fibrosis by inhibiting fibroblast differentiation. These studies provide insights into the pathogenesis of BM fibrosis during cGVHD development.


Assuntos
Síndrome de Bronquiolite Obliterante , Células-Tronco Mesenquimais , Humanos , Animais , Camundongos , Medula Óssea , Nestina , Macrófagos
3.
Opt Lett ; 49(12): 3472-3475, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38875648

RESUMO

We propose and experimentally demonstrate a dual-wavelength distributed feedback (DFB) laser array utilizing a four-phase-shifted sampled Bragg grating. By using this grating, the coupling coefficient is enhanced by approximately 2.83 times compared to conventional sampled Bragg gratings. The devices exhibit a stable dual-mode lasing achieved by introducing further π-phase shifts at 1/3 and 2/3 positions along the cavity. These devices require only one stage of lithography to define both the ridge waveguide and the gratings, mitigating issues related to misalignment between them. A dual-wavelength laser array has been fabricated with frequency spacings of 320 GHz, 500 GHz, 640 GHz, 800 GHz, and 1 THz. When integrated with semiconductor optical amplifiers, the output power of the device can reach 23.6 mW. Furthermore, the dual-wavelength lasing is maintained across a wide range of injection currents, with a power difference of <3 dB between the two primary modes. A terahertz (THz) signal has been generated through photomixing in a photoconductive antenna, with the measured power reaching 12.8 µW.

4.
Environ Sci Technol ; 58(24): 10817-10827, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38832598

RESUMO

Direct photoreduction of FeIII is a widely recognized route for accelerating FeIII/FeII cycle in photo-Fenton chemistry. However, most of the wavelengths covering the full spectral range are insufficient to supply enough photon energy for the direct reduction process. Herein, the hitherto neglected mechanism of FeIII reduction that the FeIII indirect reduction pathway initiated by light energy-dependent reactivity variation and reactive excited state (ES) was explored. Evolution of excited-state FeIII species (*FeIII) resulting from metal-centered charge excitation (MCCE) of FeIII is experimentally verified using pulsed laser femtosecond transient absorption spectroscopy with UV-vis detection and theoretically verified by quantum chemical calculation. Intense photoinduced intravalence charge transition was observed at λ = 380 and 466 nm, revealing quartet 4MCCE and doublet 2MCCE and their exponential processes. Light energy-dependent variation of *FeIII reactivity was kinetically certified by fitting the apparent rate constant of the radical-chain sequence of photo-Fenton reactions. Covalency is found to compensate for the intravalence charge separation following photoexcitation of the metal center in the MCCE state of Fenton photosensitizer. The *FeIII is established as a model, demonstrating the intravalence hole delocalization in the ES can be leveraged for photo-Fenton reaction or other photocatalytic schemes based on electron transfer chemistry.


Assuntos
Ferro , Ferro/química , Oxirredução , Peróxido de Hidrogênio/química , Cinética
5.
Ecotoxicol Environ Saf ; 275: 116235, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38520809

RESUMO

Many gastrointestinal simulation methods have been used to predict bioavailability, but the suitability of different methods for the same metal(loid)s varies widely, which inevitably affects the accuracy of human health risk assessment. Arsenic is a common and important contaminant in many contaminated land situations. It can be readily absorbed and has teratogenic and mutagenic toxicity. Therefore, in this study, four the most commonly used in vitro simulation methods (the Physiologically Based Extraction Test (PBET), In Vitro Gastrointestinal Method (IVG), Soluble Bioavailability Research Consortium (SBRC), the Unified BARGE Method (UBM)) were tested against an in vivo animal live model, to evaluate their effectiveness for the prediction of soil As bioavailability in 10 industrially contaminated soils. The soil As relative bioavailability (RBA) varied between 15% and 68% in the different soils. As bioaccessibility differed between the 4 gastro-intestinal simulation methods. Gastric phase of UBM (UBMG) predicted As relative bioavailability the best of the 4 assays (R2 = 0.81). This study provides theoretical and technical support to refine human health risk assessment of As in soils from urban industrial legacy contaminated sites.


Assuntos
Arsênio , Poluentes do Solo , Animais , Humanos , Arsênio/análise , Solo , Disponibilidade Biológica , Poluentes do Solo/análise , Poluição Ambiental
6.
Opt Express ; 31(12): 20034-20048, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381406

RESUMO

We simulate and demonstrate experimentally an inner-wall grating double slot micro ring resonator (IG-DSMRR) with a center slot ring radius of only 6.72 µm based on the silicon-on-insulator platform. This novel photonic-integrated sensor for optical label-free biochemical analysis boosts the measured refractive index (RI) sensitivity in glucose solutions to 563 nm/RIU with the limit of detection value being 3.7 × 10-6 RIU (refractive index units). The concentration sensitivity for sodium chloride solutions can reach 981 pm/%, with a minimum concentration detection limit of 0.02%. Using the combination of DSMRR and IG, the detection range is enlarged significantly to 72.62 nm, three times the free spectral range of conventional slot micro ring resonators. The measured Q-factor is 1.6 × 104, and the straight strip and double slot waveguide transmission losses are 0.9 dB/cm and 20.2 dB/cm, respectively. This IG-DSMRR combines the advantages of a micro ring resonator, slot waveguide, and angular grating and is highly desirable for biochemical sensing in liquids and gases offering an ultra-high sensitivity and ultra-large measurement range. This is the first report of a fabricated and measured double-slot micro ring resonator with an inner sidewall grating structure.

7.
Opt Lett ; 48(19): 5113-5116, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773398

RESUMO

Integrated microring resonator structures based on silicon-on-insulator (SOI) platforms are promising candidates for high-performance on-chip sensing. In this work, a novel sidewall grating slot microring resonator (SG-SMRR) with a compact size (5 µm center radius) based on the SOI platform is proposed and demonstrated experimentally. The experiment results show that the refractive index (RI) sensitivity and the limit of detection value are 620 nm/RIU and 1.4 × 10-4 RIU, respectively. The concentration sensitivity and minimum concentration detection limit are 1120 pm/% and 0.05%, respectively. Moreover, the sidewall grating structure makes this sensor free of free spectral range (FSR) limitation. The detection range is significantly enlarged to 84.5 nm in lab measurement, four times that of the FSR of conventional SMRRs. The measured Q-factor is 3.1 × 103, and the straight slot waveguide transmission loss is 24.2 dB/cm under sensing conditions. These results combined with the small form factor associated with a silicon photonics sensor open up applications where high sensitivity and large measurement range are essential.

8.
Opt Lett ; 48(23): 6108-6111, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039203

RESUMO

Polarization-sensitive photodetectors in the ultraviolet (UV) region have been favored for their great meaning in the field of military and civilian. UV photodetectors based on GaN have aroused much attention due to high photocurrent and high sensitivity. However, the dependence on external power sources and the limited sensitivity to polarized UV light significantly impede the practical application of these photodetectors in UV-polarized photodetection. Herein, a polarization-sensitive UV photodetector based on ReSe2/GaN mixed-dimensional van der Waals (vdWs) heterojunction is proposed. Owing to the high-quality junction and type-II band alignment, the responsivity and specific detectivity reach values of 870 mA/W and 6.8 × 1011 Jones, under 325 nm illumination, respectively. Furthermore, thanks to the strong in-plane anisotropy of ReSe2, the device is highly sensitive to polarized UV light with a photocurrent anisotropic ratio up to 6.67. The findings are expected to bring new opportunities for the development of highly sensitive, high-speed and energy-efficient polarization-sensitive photodetectors.

9.
Ann Hematol ; 102(10): 2865-2877, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37474631

RESUMO

Acute graft-versus-host disease (aGVHD) remains a major limitation of allogeneic hematopoietic stem cell transplantation; not all patients respond to standard glucocorticoids treatment. This study retrospectively evaluated the effects of ruxolitinib compared with basiliximab for steroid-refractory aGVHD (SR-aGVHD). One hundred and twenty-nine patients were enrolled, 81 in ruxolitinib and 48 in basiliximab group. The overall response (OR) at day 28 was higher in ruxolitinib group (72.8% vs. 54.2%, P = 0.031), as with complete response (CR) (58.0% vs. 35.4%, P = 0.013). Ruxolitinib led to significantly lower 1-year cumulative incidence of chronic GVHD (cGVHD) (29.6% vs. 43.8%, P = 0.021). Besides, ruxolitinib showed higher 1-year overall survival (OS) and 1-year cumulative incidence of failure-free survival (FFS) (OS: 72.8% vs. 50.0%, P = 0.008; FFS: 58.9% vs. 39.6%, P = 0.014). The 1-year cumulative incidence of non-relapse mortality (NRM) was lower in ruxolitinib group (16.1% vs. 37.5%, P = 0.005), and the 1-year relapse was not different. The 1-year cumulative incidence of cytomegalovirus (CMV) viremia, CMV-associated diseases and Epstein-Barr virus (EBV)-associated diseases was similar between the two groups, but EBV viremia was significantly lower in ruxolitinib group (6.2% vs. 29.2%, P < 0.001). Subgroup analyses revealed that OR and survival were similar in ruxolitinib 5 mg twice daily (bid) and 10 mg bid groups. However, ruxolitinib 10 mg bid treatment markedly reduced 1-year cumulative incidence of cGVHD compared with 5 mg bid (21.1% vs. 50.0%, P = 0.016). Our study demonstrated that ruxolitinib was superior to basiliximab in SR-aGVHD treatment and cGVHD prophylaxis, therefore should be recommended.


Assuntos
Síndrome de Bronquiolite Obliterante , Infecções por Citomegalovirus , Infecções por Vírus Epstein-Barr , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Basiliximab/uso terapêutico , Estudos Retrospectivos , Viremia , Herpesvirus Humano 4 , Esteroides/uso terapêutico , Nitrilas/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Aguda
10.
Langmuir ; 39(18): 6539-6547, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37127842

RESUMO

Attaching polymers, especially polyethylene glycol (PEG), to protein drugs has emerged as a successful strategy to prolong circulation time in the bloodstream. The hypothesis is that the flexible chain wobbles on the protein's surface, thus resisting potential nonspecific adsorption. Such a theoretical framework may be challenged when a helical polyglutamate is used to conjugate with target proteins. In this study, we investigated the structure-activity relationships of polyglutamate-interferon conjugates P(EG3Glu)-IFN using molecular simulations. Our results show that the local crowding effect induced by oligoethylene glycols (i.e., EG3) is the primary driving force for helix formation in P(EG3Glu), and its helicity can be effectively increased by reducing the free volume of the two termini. Furthermore, it was found that the steric hindrance induced by IFN is not conductive to the helicity of P(EG3Glu) but contributes to its dominant orientation relative to interferon. The orientation of IFN relative to the helical P(EG3Glu) can help to protect the protein drug from neutralizing antibodies while maintaining its bioactivity. These findings suggest that the helical structure and its orientation are critical factors to consider when updating the theoretical framework for protein-polymer conjugates.


Assuntos
Interferons , Ácido Poliglutâmico , Interferons/química , Polietilenoglicóis/química , Polímeros/química , Proteínas
11.
Phytother Res ; 37(8): 3495-3507, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37125528

RESUMO

Effective amelioration of ischemia/reperfusion (I/R)-induced intestinal injury and revealing its mechanisms remain the challenges in both preclinic and clinic. Potential mechanisms of naringin in ameliorating I/R-induced intestinal injury remain unknown. Based on pre-experiments, I/R-injured rat intestine in vivo and hypoxia-reoxygenation (H/R)-injured IEC-6 cells in vitro were used to verify that naringin-alleviated I/R-induced intestinal injury was mediated via deactivating cGAS-STING signaling pathway. Naringin improved intestinal damage using hematoxylin and eosin staining and decreased alanine aminotransferase and aspartate aminotransferase contents in plasma. Naringin decreased inflammation characterized by reducing IL-6, IL-1ß, TNF-α, and IFN-ß contents in both plasma and IEC-6 cells. Naringin mitigated oxidative stress via recovering superoxide dismutase, glutathione, and malondialdehyde levels in the I/R-injured intestine. Naringin reduced the expression of apoptotic proteins, including Bax, caspase-3, and Bcl-2, and reduced terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling-positive cells both in vivo and in vitro, and decreased Hoechst 33342 signals in vitro. cGAS, STING, p-TBK1, p-IRF3, and NF-κB expressions were up-regulated both in vivo and in vitro respectively and the up-regulated indexes were reversed by naringin. Transfection of cGAS-siRNA and cGAS-cDNA significantly down-regulated and up-regulated cGAS-STING signaling-related protein expressions, respectively, and partially weakened naringin-induced amelioration on these indexes, suggesting that deactivation of cGAS-STING signaling is the crucial target for naringin-induced amelioration on I/R-injured intestine.


Assuntos
Intestinos , Traumatismo por Reperfusão , Ratos , Animais , Transdução de Sinais , Inflamação/tratamento farmacológico , Nucleotidiltransferases/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Apoptose
12.
Sensors (Basel) ; 23(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904755

RESUMO

At present, the explosive growth of software code volume and quantity makes the code review process very labor-intensive and time-consuming. An automated code review model can assist in improving the efficiency of the process. Tufano et al., designed two automated tasks to help improve the efficiency of code review based on the deep learning approach, from two different perspectives, namely, the developer submitting the code and the code reviewer. However, they only used code sequence information and did not explore the logical structure information with a richer meaning of the code. To improve the learning of code structure information, a program dependency graph serialization algorithm PDG2Seq algorithm is proposed, which converts the program dependency graph into a unique graph code sequence in a lossless manner, while retaining the program structure information and semantic information. We then designed an automated code review model based on the pre-trained model CodeBERT architecture, which strengthens the learning of code information by fusing program structure information and code sequence information, and then fine-tuned the model according to the code review activity scene to complete the automatic modification of the code. To verify the efficiency of the algorithm, the two tasks in the experiment were compared with the best Algorithm 1-encoder/2-encoder. The experimental results show that the model we proposed has a significant improvement under the BLEU, Lewinshtein distance and ROUGE-L metrics.

13.
Molecules ; 28(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836789

RESUMO

Bacillus cereus (B. cereus) is a common foodborne pathogen causing food poisoning incidents. This study aimed to evaluate the antibacterial activity and underlying mechanism of rhamnolipids (RLs) against B. cereus. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of RLs for B. cereus were determined to be 16.0 mg/L and 32.0 mg/L, respectively. Scanning electron microscopy and fluorescence microscope images, as well as data of membrane potential, relative electric conductivity, and leakage of intracellular components revealed that RLs disrupted the integrity of the cell membrane. Furthermore, the reactive oxygen species content, catalase (CAT) and superoxide dismutase (SOD) activity indicated that RLs activated the oxidative stress response of B. cereus in response to RLs. Fresh wet noodles (FWN) were used as a food model, and RLs showed a significant killing effect on B. cereus with a sustained inhibitory effect at the concentrations ranging from 128.0 to 1024.0 mg/kg. Additionally, RLs promoted the conversion of free water to bound water in FWN, which improved the storage of FWN and made the taste more resilient and chewy. These results suggest that RLs could be a potential alternative to antimicrobial agents and preservatives for applications in food processing.


Assuntos
Anti-Infecciosos , Bacillus cereus , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Água/farmacologia
14.
Molecules ; 28(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38005393

RESUMO

A novel gas-pressurized (GP) torrefaction method at 250 °C has recently been developed that realizes the deep decomposition of cellulose in lignocellulosic solid wastes (LSW) to as high as 90% through deoxygenation and aromatization reactions. However, the deoxygenation and aromatization mechanisms are currently unclear. In this work, these mechanisms were studied through a developed molecular structure calculation method and the GP torrefaction of pure cellulose. The results demonstrate that GP torrefaction at 250 °C causes 47 wt.% of mass loss and 72 wt.% of O removal for cellulose, while traditional torrefaction at atmospheric pressure has almost no impact on cellulose decomposition. The GP-torrefied cellulose is determined to be composed of an aromatic furans nucleus with branch aliphatic C through conventional characterization. A molecular structure calculation method and its principles were developed for further investigation of molecular-level mechanisms. It was found 2-ring furans aromatic compound intermediate is formed by intra- and inter-molecular dehydroxylation reactions of amorphous cellulose, and the removal of O-containing function groups is mainly through the production of H2O. The three-ring furans aromatic compound intermediate and GP-torrefied cellulose are further formed through the polymerization reaction, which enhances the removal of ketones and aldehydes function groups in intermediate torrefied cellulose and form gaseous CO and O-containing organic molecules. A deoxygenation and aromatization mechanism model was developed based on the above investigation. This work provides theoretical guidance for the optimization of the gas-pressurized torrefaction method and a study method for the determination of molecular-level structure and the mechanism investigation of the thermal conversion processes of LSW.

15.
Environ Geochem Health ; 45(6): 2691-2704, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36131168

RESUMO

Risk assessment has been recognized as an important tool for evaluating heavy metal pollution and providing risk-based information for decision makers. In order to accurately assess the risk of heavy metals in contaminated soil to human health, it is necessary to conduct bioavailability studies on heavy metals in soil. Bioavailability of heavy metals in soils and the implications for risk assessment and land management/remediation has evolved over the decades and now has considerable practical and economic implications internationally. This article aims to explore its evolution by undertaking a bibliometric analysis of the research fields which have addressed heavy metal bioavailability in soils, with a focus on the risk assessment of contaminated land and human exposure to soil-borne metals. Bibliometric analysis techniques are applied to monitor and assess the changing research literature on the bioavailability of heavy metals in contaminated soils. Over 5000 articles were found for the period 1979-2020. The purpose was not to perform an exhaustive literature review, but to draw out trends and patterns in the literature, and to make observations on past and current priorities. Key words were extracted from the analysis and the roles of different countries in driving the research literature identified. Three phases in literature/subject development were identified. Between 1979 and 2000 (initial phase, 213 articles), studies used extraction procedures and solubility studies to investigate the roles of soil properties on metal form/speciation and focused on bioavailability to (crop) plants in agricultural soils. Between 2001 and 2010 (slow development phase, 1105 articles), attention switched to metals introduced in soil amendments and wastes, metal impacts on soil microbial processes, and incorporating bioavailability in risk assessment. More rigorous techniques were being used, such as the diffusive gradients in thin films technique, to better understand kinetic and metal speciation in soils and the quantitative relationship to bioavailability. By 2011-2020 (rapid development phase, 3137 articles), research was being conducted in many countries (site specific, often industrially contaminated and urban sites), with a focus shift to health risk assessment, remediation, and bioavailability to various ecological receptors (e.g., humans and animals), with the development of many methods of bioavailability (e.g., simulated gastrointestinal tract enzymolysis methods). Some priorities for research on soil heavy metal bioavailability are identified.


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Disponibilidade Biológica , Poluentes do Solo/análise , Metais Pesados/análise , Medição de Risco , Solo
16.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(6): 1139-1145, 2023 Nov 20.
Artigo em Zh | MEDLINE | ID: mdl-38162057

RESUMO

Objective: To investigate the effect of sleep deprivation on the metabolism of the hippocampal region in mice. Methods: The mice were randomly assigned to three groups, a control group, a 24-h sleep deprivation (SD) group, and a 48-h SD group. Each group had 10 mice. The sleep deprivation model was induced by the modified multiple platform method. The mice's anxiety-like behaviors were assessed with the open field test (OFT) and their depression-like behaviors were assessed with the sucrose preference test (SPT), the forced swimming test (FST), and tail suspension test (TST). High performance liquid chromatography (HPLC) was performed to determine the levels of 6 monoamine neurotransmitters, including 5-hydroxytryptamine (5-HT), norepinephrine (NE), dopamine (DA), gamma-aminobutyric acid (GABA), 5-dihydroxyphenylacetic acid (5-DOPAC), and homovanillic acid (HVA), and 4 amino acids, including glutamic acid (Glu), aspartic acid (Asp), serine (Ser), and taurine (Tau), in the hippocampal region. Immunofluorescence staining was performed to examine the expression of glial cells in the hippocampal region of the mice. The main indicators measured were the levels of monoamine neurotransmitters and amino acids. Results: According to the results of the behavioral analysis, in comparison with the findings for the control group, the 24-h SD mice exhibited increased consumption of sucrose in SFT, significantly decreased total immobility time in FST and TST, and increased total distance covered in OFT, while the 48-h SD mice showed decreased consumption of sucrose in SFT, prolonged total immobility time in FST and TST, and decreased total distance covered in OFT. The results of the HPLC analysis of the monoamine neurotransmitter showed that 24-h SD mice had in their hippocampal region increased levels of DA (P<0.001) and NE (P<0.01) and decreased levels of GABA (P<0.05) in comparison with those of the control mice, while their 5-HT, 5-DOPAC, and HVA levels were not significantly different from those of the control mice. In comparison with those of the control mice, the 48-h SD mice had, in their hippocampal region, decreased levels of 5-HT and NE (all P<0.05), decreased DA (P<0.01), and increased level of GABA (P<0.01), while the levels of 5-DOPAC and HAV were not significantly different. The 48-h SD group showed a significant decrease in the levels of Tau and Glu in comparison with those of the 24-h SD group (all P<0.05). According to the results of immunofluorescence assay, there was no significant difference between the control group and the 24-h SD group in the cell count of glial fibrillary acidic protein (GFAP)-positive cells, while a decline in GFAP-positive cells in comparison with that of the control group was observed in the 48-h SD group. Conclusion: SD of 24 hours may induce anxiety-like behavioral changes in mice by activating their hippocampal glial cells, upregulating the levels of 5-HT, DA, and NE, and increasing the levels of Glu and Tau in the hippocampal region. SD of 48 hours may induce depression-like behavioral changes in mice by inhibiting the activation of glial cells in the hippocampal region and regulating in the opposite direction the levels of the above-mentioned monoamine neurotransmitters and amino acids in the hippocampal region.


Assuntos
Serotonina , Privação do Sono , Camundongos , Animais , Privação do Sono/metabolismo , Aminoácidos/metabolismo , Aminoácidos/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/farmacologia , Hipocampo , Dopamina , Norepinefrina , Ácido Homovanílico/metabolismo , Ácido Homovanílico/farmacologia , Neurotransmissores/química , Neurotransmissores/metabolismo , Neurotransmissores/farmacologia , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologia , Sacarose/metabolismo , Sacarose/farmacologia
17.
Small ; 18(11): e2105070, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35048484

RESUMO

One of the important steps for realizing artificial intelligence is identifying elementary units that are beneficial for neural network construction. A type of memristive behavior in which phase-change nanoclusters nucleate adaptively in two adjacent dielectric layers with distinct distribution patterns is demonstrated. This memristive system responds in potentiation to increased stimulation strength and fire action potential after threshold stimulation. Reversible nucleation of phase-change nanoclusters is confirmed after both in situ and ex situ examinations using high-resolution transmission electron microscopy. The dynamics at the nanoscale level dominates the actions of the two dielectric layers. The oscillation response over a long period is due to the competition between crystalline and amorphous phases in the layer near the bottom electrode. Weight mutation, that is, action potential firing, is caused by the blockage of the filament in the layer near the top electrode. The memristive system is compact and able to execute complicated functions of a complete neuron and performs an important role in neuromorphic computing.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Potenciais de Ação , Neurônios/fisiologia
18.
Small ; 18(34): e2202523, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35905495

RESUMO

Polarization-sensitive photodetectors based on van der Waals heterojunctions (vdWH) have excellent polarization-resolved optoelectronic properties that can enable the applications in polarized light identification and imaging. With the development of optical microcomputer control systems (OMCS), it is crucial and energy efficient to adopt the self-powered and polarization-resolved signal-generators to optimize the circuit design of OMCS. In this work, the selenium (Se) flakes with in-plane anisotropy and p-type character are grown and incorporated with n-type tungsten disulfide (WS2 ) to construct the type-II vdWH for polarization-sensitive and self-powered photodetectors. Under 405 nm monochrome laser with 1.33 mW cm-2 power density, the photovoltaic device exhibits superior photodetection performance with the photoelectric conversion efficiency (PCE) of 3.6%, the responsivity (R) of 196 mA W-1 and the external quantum efficiency (EQE) of about 60%. The strong in-plane anisotropy of Se crystal structure gives rise to the capability of polarized light detection with anisotropic photocurrent ratio of ≈2.2 under the 405 nm laser (13.71 mW cm-2 ). Benefiting from the well polarization-sensitive and photovoltaic properties, the p-Se/n-WS2 vdWH is successfully applied in the OMCS as multivalued signal trigger. This work develops the new anisotropic vdWH and demonstrates its feasibility for applications in logic circuits and control systems.

19.
Opt Lett ; 47(23): 6237-6240, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219216

RESUMO

A four-laser array based on sampled Bragg grating distributed feedback (DFB) lasers in which each sampled period contains four phase-shift sections is proposed, fabricated, and experimentally demonstrated. The wavelength spacing between adjacent lasers is accurately controlled to 0.8 nm ± 0.026 nm and the lasers have single mode suppression ratios larger than 50 dB. Using an integrated semiconductor optical amplifier, the output power can reach 33 mW and the optical linewidth of the DFB lasers can be as narrow as 64 kHz. This laser array uses a ridge waveguide with sidewall gratings and needs only one metalorganic vapor-phase epitaxy (MOVPE) step and one III-V material etching process, simplifying the whole device fabrication process, and meeting the requirements of dense wavelength division multiplexing systems.

20.
J Gastroenterol Hepatol ; 37(6): 1119-1130, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35437816

RESUMO

BACKGROUND AND AIM: Intestinal homeostasis is closely associated with the normal intestinal luminal physiological environment. Temporary loop ileostomy changes the intestinal structure and diverts the fecal stream, thereby disturbing the intestinal environment. This study aimed to clarify the changing situation of the human intestinal mucosa barrier in the absence of a fecal stream after loop ileostomy. METHODS: We obtained paired samples from the fed (fecal stream maintained) and unfed (no fecal stream) portions of the loop ileostomy and subjected these samples to RNA sequencing. We also determined transepithelial electrical resistance. The mucus layer thickness and content of MUC2, tight junction proteins, and common antimicrobial peptides in ileum mucosa were studied. RESULTS: Transcriptome data revealed that genes associated with enhancing the intestinal barrier function of the unfed ileum were significantly decreased and genes associated with immune defense response were significantly increased. The transepithelial electrical resistance was lower and the mucus layer thickness was thinner in the unfed ileal mucosa than in the fed ileum. The MUC2, Occludin, and zonula occludens 1 content was lower in the unfed ileum than in the fed ileum. α-Defensin 5, α-defensin 6, and lysozyme content was higher in the unfed ileum than in the enterally fed ileum. CONCLUSION: Intestinal barrier function is weakened after long-term fecal diversion, but antimicrobiota defense function is strengthened. Thus, the intestinal mucosa barrier adopts an alternative stable state during fecal diversion, which may explain the clinical paucity of cases of enterogenic infection caused by loop ileostomy.


Assuntos
Ileostomia , alfa-Defensinas , Humanos , Íleo/metabolismo , Íleo/cirurgia , Mucosa Intestinal/metabolismo , Junções Íntimas , alfa-Defensinas/metabolismo
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