ABSTRACT
The stoichiometric characteristics of leaves can reflect environmental adaptation of plants, and thus the study of the relationship between them is helpful for exploring plant adaptation strategies. In this study, taking the national second-level key protection species, Ammopiptanthus mongolicus, as the research object, we set up 26 plots to collect samples, and measured the content of carbon (C), nitrogen (N), phosphorus (P) and water use efficiency (WUE) of leaves. We analyzed the relationship between leaf stoichiometric characteristics and WUE, and quantified the contributions of soil, climate, and water use efficiency to the variations of leaf stoichiometry. The results showed that C, N, and P contents in the leaves were (583.99±27.93), (24.31±2.09), and (1.83±0.06) mg·g-1, respectively. The coefficients of variation were 4.8%, 8.6%, and 3.2%, respectively, all belonging to weak variability, indicating that foliar contents of C, N and P tended to a certain stable value. The average value of N:P was 13.3, indicating that the growth of A. mongolicus was mainly limited by N. WUE was not correlated with leaf C content, but was significantly positively correlated with leaf N and P contents and N:P, and significantly negatively correlated with C:N and C:P, indicating that there was a linear synergistic trend between WUE and leaf nutrient content. The main factors influencing leaf C content and C:P were climatic factors, the leaf N content and N:P were mainly affected by soil factors, and the water use efficiency mainly affected leaf P content and C:N, indicating that the driving factors of different stoichiometric characteristics were different. The results could help eva-luate the habitat adaptation of desert plants, which would provide a theoretical basis for the conservation and management of A. mongolicus.
Subject(s)
Carbon , Nitrogen , Phosphorus , Plant Leaves , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Leaves/growth & development , China , Nitrogen/analysis , Nitrogen/metabolism , Phosphorus/analysis , Phosphorus/metabolism , Carbon/analysis , Carbon/metabolism , Ecosystem , Water/analysis , Water/metabolism , Water/chemistry , Adaptation, Physiological , Soil/chemistryABSTRACT
Solving a maze effectively relies on both perception and cognition. Studying maze-solving behavior contributes to our knowledge about these important processes. Through psychophysical experiments and modeling simulations, we examine the role of peripheral vision, specifically visual crowding in the periphery, in mental maze-solving. Experiment 1 measured gaze patterns while varying maze complexity, revealing a direct relationship between visual complexity and maze-solving efficiency. Simulations of the maze-solving task using a peripheral vision model confirmed the observed crowding effects while making an intriguing prediction that saccades provide a conservative measure of how far ahead observers can perceive the path. Experiment 2 confirms that observers can judge whether a point lies on the path at considerably greater distances than their average saccade. Taken together, our findings demonstrate that peripheral vision plays a key role in mental maze-solving.
Subject(s)
Problem Solving , Saccades , Humans , Problem Solving/physiology , Saccades/physiology , Visual Fields/physiology , Maze Learning/physiology , Male , Young Adult , Psychophysics/methods , Photic Stimulation/methods , Female , Adult , Visual Perception/physiologyABSTRACT
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), which is a label-free imaging technique, determines the spatial distribution and relative abundance of versatile endogenous metabolites in tissues. Meanwhile, matrix selection is generally regarded as a pivotal step in MALDI tissue imaging. This study presents the first report of a novel MALDI matrix, 2-hydroxy-5-nitro-3-(trifluoromethyl)pyridine (HNTP), for the in situ detection and imaging of endogenous metabolites in rat liver and brain tissues by MALDI-MS in positive-ion mode. The HNTP matrix exhibits excellent characteristics, including strong ultraviolet absorption, µm-scale matrix crystals, high chemical stability, low background ion interference, and high metabolite ionization efficiency. Notably, the HNTP matrix also shows superior detection capabilities, successfully showing 185 detectable metabolites in rat liver tissue sections. This outperforms the commonly used matrices of 2,5-dihydroxybenzoic acid and 2-mercaptobenzothiazole, which detect 145 and 120 metabolites from the rat liver, respectively. Furthermore, a total of 152 metabolites are effectively detected and imaged in rat brain tissue using the HNTP matrix, and the spatial distribution of these compounds clearly shows the heterogeneity of the rat brain. The results demonstrate that HNTP is a new and powerful positive-ion mode matrix to enhance the analysis of metabolites in biological tissues by MALDI-MSI.
Subject(s)
Diagnostic Imaging , Liver , Rats , Animals , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Liver/metabolism , Pyridines/analysisABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herbal medicine Gegen Qinlian Decoction (GQD) has been clinically shown to be an effective treatment of ulcerative colitis (UC) in China. However, the underlying mechanism of GQD's anti-ulcerative colitis properties and its effect on gut microbiota still deserve further exploration. AIM OF THE STUDY: This study observed the regulatory effects of GQD on Th2/Th1 and Tregs/Th17 cells balance, the NOD-like receptor family pyrin domain containing 3 (NLRP3) infammasome and gut microbiota in TNBS-induced UC in BALB/c mice. MATERIALS AND METHODS: 61 main chemical compounds in the GQD were determined by UPLC-Q-TOF/MS. The UC BALB/c model was established by intrarectal administration of trinitrobenzene sulfonic acid (TNBS), and GQD was orally administered at low and high dosages of 2.96 and 11.83 g/kg/day, respectively. The anti-inflammatory effects of GQD for ulcerative colitis were evaluated by survival rate, body weight, disease activity index (DAI) score, colonic weight and index, spleen index, hematoxylin-eosin (HE) staining and histopathological scores. Flow cytometry was used to detect the percentage of CD4, Th1, Th2, Th17 and Tregs cells. The levels of Th1-/Th2-/Th17-/Tregs-related inflammatory cytokines and additional proinflammatory cytokines (IL-1ß, IL-18) were detected by CBA, ELISA, and RT-PCR. The expressions of GATA3, T-bet, NLRP3, Caspase-1, IL-Iß, Occludin and Zonula occludens-1 (ZO-1) on colon tissues were detected by Western blot and RT-PCR. Transcriptome sequencing was performed using colon tissue and 16S rRNA gene sequencing was performed on intestinal contents. Fecal microbiota transplantation (FMT) was employed to assess the contribution of intestinal microbiota and its correlation with CD4 T cells and the NLRP3 inflammasome. RESULTS: GQD increased the survival rate of TNBS-induced UC in BALB/c mice, and significantly improved their body weight, DAI score, colonic weight and index, spleen index, and histological characteristics. The intestinal barrier dysfunction was repaired after GQD administration through promoting the expression of tight junction proteins (Occludin and ZO-1). GQD restored the balance of Th2/Th1 and Tregs/Th17 cells immune response of colitis mice, primarily inhibiting the increase in Th2/Th1 ratio and their transcription factor production (GATA3 and T-bet). Morever, GQD changed the secretion of Th1-/Th2-/Th17-/Tregs-related cytokines (IL-2, IL-12, IL-5, IL-13, IL-6, IL-10, and IL-17A) and reduced the expressions of IL-1ß, IL-18. Transcriptome results suggested that GQD could also remodel the immune inflammatory response of colitis by inhibiting NOD-like receptor signaling pathway, and Western blot, immunohistochemistry and RT-PCR further revealed that GQD exerted anti-inflammatory effects by inhibiting the NLRP3 inflammasome, such as down-regulating the expression of NLRP3, Caspase-1 and IL-1ß. More interestingly, GQD regulated gut microbiota dysbiosis, suppressed the overgrowth of conditional pathogenic gut bacteria like Helicobacter, Proteobacteria, and Mucispirillum, while the probiotic gut microbiota, such as Lactobacillus, Muribaculaceae, Ruminiclostridium_6, Akkermansia, and Ruminococcaceae_unclassified were increased. We further confirmed that GQD-treated gut microbiota was sufficient to relieve TNBS-induced colitis by FMT, involving the modulation of Th2/Th1 and Tregs/Th17 balance, inhibition of NLRP3 inflammasome activation, and enhancement of colonic barrier function. CONCLUSIONS: GQD might alleviate TNBS-induced UC via regulating Th2/Th1 and Tregs/Th17 cells Balance, inhibiting NLRP3 inflammasome and reshaping gut microbiota, which may provide a novel strategy for patients with colitis.
Subject(s)
Colitis, Ulcerative , Colitis , Drugs, Chinese Herbal , Gastrointestinal Microbiome , Humans , Mice , Animals , Colitis, Ulcerative/chemically induced , Colitis, Ulcerative/drug therapy , Drugs, Chinese Herbal/adverse effects , Inflammasomes/metabolism , Interleukin-18/metabolism , Interleukin-18/pharmacology , Interleukin-18/therapeutic use , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Th17 Cells , Occludin/metabolism , RNA, Ribosomal, 16S/metabolism , Mice, Inbred CBA , Colitis/drug therapy , Cytokines/metabolism , Trinitrobenzenes/metabolism , Trinitrobenzenes/pharmacology , Trinitrobenzenes/therapeutic use , Anti-Inflammatory Agents/pharmacology , Body Weight , Caspases/metabolism , Disease Models, Animal , ColonABSTRACT
BACKGROUND/PURPOSE: We evaluated the utility of combining quantitative pulmonary vasculature measures with clinical factors for predicting pulmonary hemorrhage after computed tomography (CT)-guided lung biopsy. METHODS: Patients who underwent CT-guided lung biopsy were retrospectively included in this study. Clinical and radiographic vasculature variables were evaluated as predictors of pulmonary hemorrhage. The radiographic pulmonary vascular analysis included vessel count, density, diameter, and area, and also blood volume in small vessels with a cross-sectional area ≤5 mm2 (BV5) and total blood vessel volume (TBV) in the lungs. Univariate and multivariate logistic regressions were used to identify the independent risk factors of higher-grade pulmonary hemorrhage and establish the prediction model presented as a nomogram. RESULTS: The study included 126 patients; discovery cohort n = 103, and validation cohort n = 23. All pulmonary hemorrhage, higher-grade (grade ≥2) pulmonary hemorrhage, and hemoptysis occurred in 42.9%, 15.9%, and 3.2% of patients who underwent CT-guided lung biopsies. In the discovery cohort, patients with larger lesion depth (p = 0.013), higher vessel density (p = 0.033), and higher BV5 (p = 0.039) were more likely to experience higher-grade hemorrhage. The nomogram prediction model for higher-grade hemorrhage built by the discovery cohort showed similar performance in the validation cohort. CONCLUSIONS: Higher-grade pulmonary hemorrhage may occur after CT-guided lung biopsy. Lesion depth, vessel density, and BV5 are independent risk factors for higher-grade pulmonary hemorrhage. Nomograms integrating clinical parameters and radiographic pulmonary vasculature measures offer enhanced capability for assessing hemorrhage risk following CT-guided lung biopsy, thereby facilitating improved patient clinical care.
ABSTRACT
Scanning/transmission electron microscopy (STEM) is a powerful characterization tool for a wide range of materials. Over the years, STEMs have been extensively used for in situ studies of structural evolution and dynamic processes. A limited number of STEM instruments are equipped with a secondary electron (SE) detector in addition to the conventional transmitted electron detectors, i.e. the bright-field (BF) and annular dark-field (ADF) detectors. Such instruments are capable of simultaneous BF-STEM, ADF-STEM and SE-STEM imaging. These methods can reveal the 'bulk' information from BF and ADF signals and the surface information from SE signals for materials <200 nm thick. This review first summarizes the field of in situ STEM research, followed by the generation of SE signals, SE-STEM instrumentation and applications of SE-STEM analysis. Combining with various in situ heating, gas reaction and mechanical testing stages based on microelectromechanical systems (MEMS), we show that simultaneous SE-STEM imaging has found applications in studying the dynamics and transient phenomena of surface reconstructions, exsolution of catalysts, lunar and planetary materials and mechanical properties of 2D thin films. Finally, we provide an outlook on the potential advancements in SE-STEM from the perspective of sample-related factors, instrument-related factors and data acquisition and processing.
ABSTRACT
Regulation of the proline metabolic pathway is essential for the accumulation of proline under abiotic stress and for the amelioration of plant stress resistance. Δ1-pyrroline-5-carboxylate synthase (P5CS), pyrroline-5-carboxylate reductase (P5CR), ornithine transaminase (δ-OAT), proline dehydrogenase (PDH), pyrroline-5-carboxylate dehydrogenase (P5CDH), and proline transporter (ProT) are the key enzymes in the proline metabolic pathway. However, the gene families responsible for proline metabolism have not yet been identified or reported in alfalfa. In this study, a total of 12 MsP5CSs, 4 MsP5CRs, 3 MsOATs, 6 MsPDHs, 2 MsP5CDHs, and 5 MsProTs were identified in the genome of alfalfa, and the members of the same subfamily had similar gene structures and conserved motifs. Analysis of cis-regulatory elements revealed the presence of light-responsive, hormone-regulated, and stress-responsive elements in the promoter regions of alfalfa proline metabolism-related genes. Following treatment with saline-alkali, the expression of MsP5CSs, MsP5CRs, MsOATs, and MsProTs was significantly upregulated, whereas the expression of MsPDH1.1, MsPDH1.3, and MsP5CDH was significantly downregulated. The proline content and enzyme activity of P5CS gradually increased, whereas the enzyme activity of PDH gradually decreased as the duration of stress increased. Root growth rates decreased upon MsP5CS1a suppression (MsP5CS1a-RNAi) in the hairy roots of alfalfa compared to the empty vector line under saline-alkali stress. These results show that proline metabolism-related genes play an important role in the saline-alkali stress tolerance of alfalfa and provide a theoretical basis for further research on the functions of proline metabolism-related genes in alfalfa in response to saline-alkali stress.
Subject(s)
Medicago sativa , Proline Oxidase , Medicago sativa/genetics , Medicago sativa/metabolism , Proline Oxidase/genetics , Proline Oxidase/metabolism , Pyrroline Carboxylate Reductases , Proline/metabolism , Computational Biology , Stress, Physiological/geneticsABSTRACT
OBJECTIVES: To observe the effect of electroacupuncture (EA) in obese rats with insulin resistance (IR) through regulating intestinal silent information regulator 1 (SIRT1)/Toll-like receptor 4 (TLR4) signaling pathway, so as to explore the underlying mechanism of EA in improving obesity-induced IR. METHODS: A total of 40 Wistar rats were randomly divided into 4 groups, i.e. normal group, model group, EA group and EA combined with inhibitor group, with 10 rats in each group. The obesity-induced IR model was induced by feeding high-fat diet for 8 weeks. EA (2 Hz, 1mA) was applied at "Zhongwan"(CV12), "Guanyuan"(CV4), "Zusanli"(ST36) and "Fenglong" (ST40) for 10 min, 3 times a week for 8 weeks in both EA and EA combined with inhibitor groups. Sirtinol, an inhibitor of SIRT1 was injected into the tail vein (1 mg/kg), 3 times a week for 8 weeks in EA combined with inhibitor group. The body weight, glucose infusion rate (GIR) of rats in each group were recorded. The contents of serum C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and lipopolysaccharide (LPS) were detected by ELISA. Mucosal morphological changes in the small intestine was observed by HE staining and was graded using Chiu's score. The protein relative expression levels of SIRT1 and TLR4 and the co-labeling of SIRT1 with TLR4 in the small intestine was detected by Western blot and double immunofluorescence staining, separately. RESULTS: Compared with the normal group, the body weight, serum contents of CRP, TNF-α, IL-6, LPS, Chiu's score, TLR4 protein relative expression level and percentage of TLR4 positive expression area were increased (P<0.01, P<0.05), while the GIR, SIRT1 protein expression, percentage of SIRT1 positive expression area and SIRT1/TLR4 were decreased (P<0.01) in the model group. The pathological injury of small intestine mucosa was severe, accompanied with inflammatory cell infiltration in the model group. Following interventions, the body weight, serum contents of CRP, TNF-α and LPS, Chiu's score, TLR4 protein relative expression level and percentage of TLR4 positive expression area were decreased(P<0.01, P<0.05), and the GIR was increased (P<0.01), the pathological injury and inflammatory cell infiltration of small intestine mucosa were reduced in both EA and EA combined with inhibitor groups in contrast to the model group. Compared with the model group, the serum IL-6 content was significantly decreased (P<0.01), and the SIRT1 protein relative expression level and percentage of positive expression area, SIRT1/TLR4 were increased (P<0.01, P<0.05) in the EA group. Compared with the EA group, EA combined with inhibitor group showed the body weight, serum CRP, IL-6, LPS, Chiu's score, TLR4 protein relative expression level and TLR4 positive expression area were increased (P<0.01, P<0.05), and the GIR level , SIRT1 relative expression level, SIRT1/TLR4 ratio were decreased (P<0.05, P<0.01). CONCLUSIONS: EA can reduce the body weight and ameliorate peripheral insulin sensitivity in IR obese rats, which may be related with its function in regulating intestinal SIRT1/TLR4 signaling pathway to reduce inflammatory response.
Subject(s)
Electroacupuncture , Insulin Resistance , Rats , Animals , Rats, Wistar , Insulin Resistance/genetics , Sirtuin 1/genetics , Lipopolysaccharides , Toll-Like Receptor 4/genetics , Interleukin-6 , Tumor Necrosis Factor-alpha/genetics , Obesity/genetics , Obesity/therapy , Signal TransductionABSTRACT
Hypercalcaemia associated with malignancy is a complication of advanced tumors. Lactic acidosis is also an extremely rare paraneoplastic syndrome of malignancy, and the presence of both usually indicates an extremely poor prognosis for the tumour. Diffuse large B-cell lymphoma is the most common type of non-Hodgkin's lymphoma and is also a common aggressive lymphoma. It is extremely rare for patients with diffuse large B-cell lymphoma to develop both hypercalcaemia and severe lactic acidosis. In this article, we report a case of CD5 positive diffuse large B-cell lymphoma with hypercalcaemic crisis and persistent lactic acidosis, in which calcium was rapidly reduced to normal after rehydration, diuresis, calcitonin and zoledronate, and continuous renal replacement therapy (CRRT). After correction of acidosis with sodium bicarbonate, diuresis, vitamin B1 and CRRT, the patient's lactate remained at a high level. The aim of this article is to analyse the experience of the combination of hypercalcaemia and intractable lactic acidosis, which should be considered as a serious electrolyte disorder possibly associated with abnormal metabolism of malignant tumors, and to identify and treat the primary lesion as early as possible.
ABSTRACT
The systemic inflammatory response caused by various pathogenic factors is a key stage in the development of acute respiratory distress syndrome (ARDS). At present, suppression of the inflammatory response and symptomatic support are main methods for the treatment of ARDS. Alveolar epithelial autophagy has an important role in the regulation of the inflammatory response in ARDS. Autophagy is a normal immune mechanism in the body, and it is a metabolic process by which phagocytes degrade intracellular components with the help of lysosomes to maintain intracellular homeostasis. Current studies have shown that pathogenic factors both inside and outside the lung can cause alveolar epithelial cells to form an unfavorable internal environment of hypoxia, starvation, infection, and even apoptosis by triggering inflammatory responses, leading to autophagy dysfunction. Excessive autophagy activation can continue to aggravate inflammatory responses. Autophagy related proteins such as Beclin1, microtubule-associated protein 1 light chain 3 (LC3), mammalian target of rapamycin (mTOR), and p62 are common autophagic markers in current research, which play a crucial role in regulating the autophagic process and the development of lung injury. Therefore, the expression of cellular autophagy genes can be used as early markers and important mechanisms of lung injury in septic ARDS. The Hippo signaling pathway is derived from the protein kinase Hippo in Drosophila, and the Hippo and autophagy are two conserved pathways that are essential for the protection of homeostasis in vivo. The mutual regulation of Hippo signaling pathway and autophagy is currently a hot topic in the academic community. This paper reviews the relevant literature to explore whether the Hippo signaling pathway can regulate cellular autophagy to alleviate the inflammatory response in septic ARDS, so as to provide further research directions for the treatment of ARDS.
Subject(s)
Lung Injury , Respiratory Distress Syndrome , Sepsis , Humans , Hippo Signaling Pathway , AutophagyABSTRACT
Lymphoid-tyrosine phosphatase (LYP) is mainly expressed in the immune system and plays an important role in the T-cell receptor (TCR) signaling pathway and tumor immunity. Herein, we identify benzofuran-2-carboxylic acid as a potent pTyr mimic and design a new series of new LYP inhibitors. The most active compound, D34 and D14, reversibly inhibits LYP (Ki = 0.93 µM and 1.34 µM) and possess a certain degree of selectivity toward other phosphatases. Meanwhile, D34 and D14 regulate the TCR signaling by specifically inhibiting LYP. In particular, D34 and D14 significantly suppress tumor growth in an MC38 syngeneic mouse model by boosting antitumor immunity, including activation of T-cell and inhibition of M2 macrophage polarization. Moreover, treatment of D34 or D14 upregulate PD-1/PD-L1 expression, which can be leveraged with PD-1/PD-L1 inhibition to augment immunotherapy. In summary, our study demonstrates the feasibility of targeting LYP for cancer immunotherapy and provides new lead compounds for further drug development.
Subject(s)
Benzofurans , Neoplasms , Animals , Mice , B7-H1 Antigen , Benzofurans/pharmacology , Carboxylic Acids , Immunotherapy , Organic Chemicals , Programmed Cell Death 1 Receptor , Protein Tyrosine Phosphatases , Receptors, Antigen, T-Cell/metabolism , TyrosineABSTRACT
Mixed pitch gratings are developed for the optical addressing of trapped 88Sr+ ion by means of simulation and experimental measurement approaches. Meanwhile, Python-based data analysis techniques were developed to analyze simulated and measured beam profiles. A fixed pitch grating with a pitch of 1.2 µm was used as a reference, and a mixed pitch grating with pitches of 1.1/1.2 µm of various ratios are investigated. The Python-based data analysis codes demonstrates highly automated capability in processing both simulated and measured beam profile data to compute key parameters, including beam waist and Gaussian fitting. Mixed pitch grating delivers light beam with smaller beam waist (17.4 µm) compared to the fixed pitch grating (26.4 µm), exhibiting â¼34% beam waist reduction.
ABSTRACT
Acetamiprid is poisonous to mammals due to severe acetamiprid-induced oxidative stress that could cause mitochondrial dysfunctions, lipid and protein oxidation, inflammation, apoptosis, and DNA damage. Evidence has accumulated for the role of oxidative stress in changing structures and functions of transfer RNAs (tRNAs) by inducing tRNA cleavage, reprogramming tRNA modifications and impairing aminoacyl-tRNA synthetase editing sites. However, the impact of acetamiprid-induced oxidative stress on tRNA is still unknown. Here, we investigated the effects of acetamiprid on cell viability, reactive oxygen species (ROS) levels, DNA damage, cellular oxidized nucleotide concentrations, and oxidative damage to tRNA in HepG2 cells and LO2 cells. Acetamiprid can cause the significant increment of ROS and DNA oxidative damage. In this study, an integrated approach was established to simultaneously study the network of oxidized nucleotides and explore the tRNA oxidative damage after acetamiprid exposure. A simple and high-throughput liquid chromatography with tandem mass spectrometry (LC-MS/MS) method coupled with (trimethylsilyl)diazomethane (TMSD) derivatization was successfully developed to quantify 12 cellular oxidized nucleotides that cannot be detected using traditional detection methods because of the huge interferences from naturally abundant nucleotides. Meanwhile, the accumulation rate and the locating sites of 8-oxo-2, 7-dihydro-guanine (8-oxo-G) in tRNA were inspected using the established N-(tert-Butyldimethylsilyl)-N-methyl-trifluoroacetamide (MTBSTFA) labeling-based tRNA profiling method. After acetamiprid treatment, the increment of oxidized nucleoside triphosphates is smaller than that of their corresponding mono- and diphosphates, as well as the dephosphorylated nucleosides, on account of the existence of sanitization enzymes. Several tRNA fragments, CUC[m1A]Gp, CACGp, [Cm]C[m2G]p, and DDGp, are significantly downregulated in acetamiprid-treated HepG2 cells, while only [Cm]C[m2G]p in acetamiprid-treated LO2 cells. According to the profiling results, the significantly changed fragment CUC[m1A]Gp might be caused by the oxidation of guanine (G) to form 8-oxo-G at position 15 in human tRNAphe([Gm]AA), providing more information about the effect of oxidized nucleobases on tRNA's functions.
Subject(s)
Nucleotides , Tandem Mass Spectrometry , Animals , Humans , Nucleotides/metabolism , Reactive Oxygen Species , Chromatography, Liquid , Oxidative Stress , RNA, Transfer/metabolism , Guanine/metabolism , Mammals/metabolismABSTRACT
We used a novel Peltier anticontamination device (PAC) to reduce carbon contamination upon electron beam irradiation in scanning electron microscopy through a reduction of hydrocarbon molecules in the specimen chamber. Unlike liquid-nitrogen based cold traps, the PAC operates free of user maintenance and is suitable for lengthy imaging sessions without degradation of the anticontamination performance. Its performance as an alternative cold trap method provides considerable reduction of electron beam-assisted carbon build-up. We compared the thickness of carbon contamination deposited upon prolonged electron beam scans with the PAC system on and off. Topographical structures of the carbon build-up were characterized using atomic force microscopy. We report that under identical beam parameters, thickness of the carbon contamination was reduced by over 79 % for area scans (1.2 × 1.2 µm2), and by two orders of magnitude for stationary point scans when the PAC cooling mode is engaged.
ABSTRACT
The investigation of brain networks and neural circuits involves the crucial aspects of observing and modulating neurophysiological activity. Recently, opto-electrodes have emerged as an efficient tool for electrophysiological recording and optogenetic stimulation, which has greatly facilitated the analysis of neural coding. However, implantation and electrode weight control have posed significant challenges in achieving long-term and multi-regional brain recording and stimulation. To address this issue, we have developed a mold and custom-printed circuit board-based opto-electrode. We report successful opto-electrode placement and high-quality electrophysiological recordings from the default mode network (DMN) of the mouse brain. This novel opto-electrode facilitates synchronous recording and stimulation in multiple brain regions and holds promise for advancing future research on neural circuits and networks.
ABSTRACT
Myo-inositol oxygenase (MIOX), a pivotal enzyme in the myo-inositol oxygenation pathway, catalyzes the cleavage of myo-inositol to UDP-glucuronic acid and plays a major role in plant adaptation to abiotic stress factors. However, studies pertaining to the MIOX gene family in alfalfa (Medicago sativa L.) are lacking. Therefore, this study characterized ten MsMIOX genes in the alfalfa genome. These genes were divisible into two classes distributed over three chromosomes and produced 12 pairs of fragment repeats and one pair of tandem repeats. Physicochemical properties, subcellular location, protein structure, conserved motifs, and gene structure pertinent to these MsMIOX genes were analyzed. Construction of a phylogenetic tree revealed that similar gene structures and conserved motifs were present in the same MsMIOX groups. Analysis of cis-acting elements revealed the presence of stress- and hormone-induced expression elements in the promoter regions of the MsMIOX genes. qRT-PCR analysis revealed that MsMIOX genes could be induced by various abiotic stress factors, such as salt, saline-alkali, drought, and cold. Under such conditions, MIOX activity in alfalfa was significantly increased. Heterologous MsMIOX2 expression in yeast enhanced salt, saline-alkali, drought, and cold tolerance. Overexpression of MsMIOX2 in the hairy roots of alfalfa decreased O2- and H2O2 content and enhanced the abiotic stress tolerance. This study offers comprehensive perspectives on the functional features of the MsMIOX family and provides a candidate gene for improving the abiotic stress tolerance of alfalfa.
Subject(s)
Inositol Oxygenase , Medicago sativa , Medicago sativa/genetics , Medicago sativa/metabolism , Inositol Oxygenase/genetics , Inositol Oxygenase/metabolism , Hydrogen Peroxide/metabolism , Phylogeny , Stress, Physiological/genetics , Sodium Chloride/pharmacology , Inositol/metabolism , Gene Expression Regulation, Plant , Plant Proteins/metabolismABSTRACT
Li3 PS4 shows great potential as solid electrolyte for all-solid-state lithium batteries (ASSLBs) due to its high Li-ion conductivity and excellent mechanical properties. However, its poor interfacial stability with bare high-nickel active materials in the cathode mixture inhibits the energy density and electrochemical performances of the corresponding LiNi0.6 Mn0.2 Co0.2 O2 /Li3 PS4 /Li-In battery. The Li3 InCl6 electrolyte with good electrochemical/chemical stability with bare LiNi0.6 Mn0.2 Co0.2 O2 (NCM622), which acts both as a Li-ion additive in the cathode mixture and as an isolation layer to isolate the direct contact between the sulfide electrolytes and active materials, providing superior solid/solid interface stabilities in the assembled battery. XPS and TEM results confirm that this strategy can mitigate the side reactions between the bare NCM622 and Li3 PS4 electrolytes. In-situ EIS and DRT results prove that this grading utilization of different solid electrolytes can greatly alleviate the poor electrochemical stability between those two materials, yielding smaller interfacial resistances. The corresponding battery delivers high discharge capacities at various C-rates under different operating temperatures. It delivers a much higher initial discharge capacity of 187.7â mAh g-1 (vs. 92.5â mAh g-1 ) at 0.1â C with a coulombic efficiency of 87.6% (vs. 71.1%) at room temperature. Moreover, this battery can even show highly reversible capacity with excellent cyclability when the operating temperature lowers to 0 and -20 °C. This work provides a hierarchical utilization strategy to fabricate sulfide electrolytes-based ASSLBs with high energy density and superior cycling performance combined with highly-oxidation cathode materials.
Subject(s)
Body Fluids , Lithium , Temperature , Electrolytes , SulfidesABSTRACT
Intestinal absorption of food is one of the sources of glucose. Insulin resistance and impaired glucose tolerance caused by lifestyle and diet are the precursors of type 2 diabetes. Patients with type 2 diabetes have trouble controlling their blood sugar levels. For long-term health, strict glycemic management is necessary. Although it is thought to be well correlated with metabolic diseases like obesity, insulin resistance, and diabetes, its molecular mechanism is still not completely understood. Disturbed microbiota triggers the gut immune response to reshape the gut homeostasis. This interaction not only maintains the dynamic changes of intestinal flora, but also preserves the integrity of the intestinal barrier. Meanwhile, the microbiota establishes a systemic multiorgan dialog on the gut-brain and gut-liver axes, intestinal absorption of a high-fat diet affects the host's feeding preference and systemic metabolism. Intervention in the gut microbiota can combat the decreased glucose tolerance and insulin sensitivity linked to metabolic diseases both centrally and peripherally. Moreover, the pharmacokinetics of oral hypoglycemic medications are also influenced by gut microbiota. The accumulation of drugs in the gut microbiota not only affects the drug efficacy, but also changes the composition and function of them, thus may help to explain individual therapeutic variances in pharmacological efficacy. Regulating gut microbiota through healthy dietary patterns or supplementing pro/prebiotics can provide guidance for lifestyle interventions in people with poor glycemic control. Traditional Chinese medicine can also be used as complementary medicine to effectively regulate intestinal homeostasis. Intestinal microbiota is becoming a new target against metabolic diseases, so more evidence is needed to elucidate the intricate microbiota-immune-host relationship, and explore the therapeutic potential of targeting intestinal microbiota.