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1.
Plant Cell ; 35(8): 2929-2951, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37177994

RESUMO

Root nodules are major sources of nitrogen for soybean (Glycine max (L.) Merr.) growth, development, production, and seed quality. Symbiotic nitrogen fixation is time-limited, as the root nodule senesces during the reproductive stage of plant development, specifically during seed development. Nodule senescence is characterized by the induction of senescence-related genes, such as papain-like cysteine proteases (CYPs), which ultimately leads to the degradation of both bacteroids and plant cells. However, how nodule senescence-related genes are activated in soybean is unknown. Here, we identified 2 paralogous NAC transcription factors, GmNAC039 and GmNAC018, as master regulators of nodule senescence. Overexpression of either gene induced soybean nodule senescence with increased cell death as detected using a TUNEL assay, whereas their knockout delayed senescence and increased nitrogenase activity. Transcriptome analysis and nCUT&Tag-qPCR assays revealed that GmNAC039 directly binds to the core motif CAC(A)A and activates the expression of 4 GmCYP genes (GmCYP35, GmCYP37, GmCYP39, and GmCYP45). Similar to GmNAC039 and GmNAC018, overexpression or knockout of GmCYP genes in nodules resulted in precocious or delayed senescence, respectively. These data provide essential insights into the regulatory mechanisms of nodule senescence, in which GmNAC039 and GmNAC018 directly activate the expression of GmCYP genes to promote nodule senescence.


Assuntos
Cisteína Proteases , Nódulos Radiculares de Plantas , Nódulos Radiculares de Plantas/metabolismo , Glycine max/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fixação de Nitrogênio/genética , Cisteína Proteases/genética , Simbiose/genética , Regulação da Expressão Gênica de Plantas/genética
2.
Proc Natl Acad Sci U S A ; 120(13): e2210791120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36947519

RESUMO

Adaptive changes in crops contribute to the diversity of agronomic traits, which directly or indirectly affect yield. The change of pubescence form from appressed to erect is a notable feature during soybean domestication. However, the biological significance and regulatory mechanism underlying this transformation remain largely unknown. Here, we identified a major-effect locus, PUBESCENCE FORM 1 (PF1), the upstream region of Mao1, that regulates pubescence form in soybean. The insertion of a Ty3/Gypsy retrotransposon in PF1 can recruit the transcription factor GAGA-binding protein to a GA-rich region, which up-regulates Mao1 expression, underpinning soybean pubescence evolution. Interestingly, the proportion of improved cultivars with erect pubescence increases gradually with increasing latitude, and erect-pubescence cultivars have a higher yield possibly through a higher photosynthetic rate and photosynthetic stability. These findings open an avenue for molecular breeding through either natural introgression or genome editing toward yield improvement and productivity.


Assuntos
Glycine max , Retroelementos , Retroelementos/genética , Glycine max/genética , Fenótipo , Regiões Promotoras Genéticas/genética
3.
Small ; : e2402402, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949051

RESUMO

Doping transition metal oxide spinels with metal ions represents a significant strategy for optimizing the electronic structure of electrocatalysts. Herein, a bimetallic Fe and Ru doping strategy to fine-tune the crystal structure of CoV2O4 spinel for highly enhanced oxygen evolution reaction (OER) is presented performance. The incorporation of Fe and Ru is observed at octahedral sites within the CoV2O4 structure, effectively modulating the electronic configuration of Co. Density functional theory calculations have confirmed that Fe acts as a novel reactive site, replacing V. Additionally, the synergistic effect of Fe, Co, and Ru effectively optimizes the Gibbs free energy of the intermediate species, reduces the reaction energy barrier, and accelerates the kinetics toward OER. As expected, the best-performing CoVFe0.5Ru0.5O4 displays a low overpotential of 240 mV (@10 mA cm-2) and a remarkably low Tafel slope of 38.9 mV dec-1, surpassing that of commercial RuO2. Moreover, it demonstrates outstanding long-term durability lasting for 72 h. This study provides valuable insights for the design of highly active polymetallic spinel electrocatalysts for energy conversion applications.

4.
Inorg Chem ; 63(10): 4574-4582, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38414342

RESUMO

The aqueous carbonation of calcium silicate (CS), a representative alkaline-earth silicate, has been widely explored in studies of carbon dioxide (CO2) mineralization. In this context, we conducted a specific comparison of the carbonation behaviors between the crystalline calcium silicate (CCS) and amorphous calcium silicate (ACS) across a pH range from 9.0 to 12.0. Interestingly, we observed opposite pH dependencies in the carbonation efficiencies (i.e., CaO conversion into CaCO3 in 1 M Na2CO3/NaHCO3 solution under ambient conditions) of CCS and ACS─the carbonation efficiency of CCS decreased with increasing the solution basicity, while that of ACS showed an inverse trend. In-depth insights were gained through in situ Raman characterizations, indicating that these differing trends appeared to originate from the polymerization/depolymerization behaviors of silicates released from minerals. More specifically, higher pH conditions seemed to favor the carbonation of minerals containing polymerized silica networks. These findings may contribute to a better understanding of the fundamental factors influencing the carbonation behaviors of alkaline earth silicates through interfacial coupled dissolution and precipitation processes. Moreover, they offer valuable insights for selecting optimal carbonation conditions for alkaline-earth silicate minerals.

5.
Antonie Van Leeuwenhoek ; 117(1): 13, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170218

RESUMO

A Gram-stain-negative, motile (by single polar flagellum) and rod-shaped bacterium, designated W1-6T, was isolated from a sediment of drainage ditch in winery in Guiyang, south-western China. Strain W1-6T showed the highest 16S rRNA gene sequence similarities with the type strain of Acidovorax wautersii (98.1%) and Simplicispira lacusdiani (97.9%). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain W1-6T was placed adjacent to the members of the genus Simplicispira and formed a separat subclade. Cells showed oxidase and catalase negative reactions. The only respiratory quinone detected was ubiquinone-8 (Q-8). Summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), C16:0 and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) were predominant cellular fatty acids (> 10%) of strain W1-6T. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and five unidentified phospholipids were found in the polar lipid extraction. The genomic DNA G + C content was 65.6%. Strain W1-6T shared the highest digital DNA-DNA hybridization [dDDH, (27.6%)] and average nucleotide identity [ANI (84.3%)] values with the type strain of S. lacusdiani. The dDDH and ANI values were below the cutoff level (dDDH 70%; ANI 95-96%) for species delineation. The polyphasic characteristics indicated that the strain W1-6T represents a novel species of the genus Simplicispira, for which the name Simplicispira sedimenti sp. nov. is proposed. The type strain is W1-6T (= CGMCC 1.16274T = NBRC 115624T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , China , Ubiquinona , DNA , Drenagem , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética
6.
Blood Purif ; 53(5): 386-395, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38194932

RESUMO

INTRODUCTION: Insufficient withdrawal duration of antithrombotics leads to excessive bleeding after major surgery. We hypothesize that intraoperative hemoadsorption (HA) can reduce postoperative allogeneic transfusion requirements and excessive bleeding events (EBE), without an increase in ischemic/thromboembolic events (ITE) in patients who have taken antithrombotics and undergone nonelective cardiac surgery. METHODS: A total of 460 patients admitted to our hospital from 2018 to 2022 were included in this study and divided into two groups: HA and non-HA. Because of the risk of bias due to differences in antithrombotic type, withdrawal duration, or basic coagulation function, propensity score matching was used for analyses. RESULTS: Out of 154 cases in the HA group, 144 pairs were successfully matched. No HA safety events such as hemolysis, hypotension, or device failure occurred. After matching, the two groups were found to be comparable in preoperative antithrombotic type, withdrawal duration, platelets and coagulation function, and demographic and perioperative characteristics. Although the HA group did not have a reduced incidence of EBE, this group exhibited significant decreases in the transfusion rate and volume, the incidence of ITE, acute kidney injury, and central nervous system injury. CONCLUSIONS: For patients who have undergone nonelective cardiac surgery and taken antithrombotics, HA can simply and safely rebalance the postoperative coagulation system and have associations with reduced transfusion and postoperative ITE.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Fibrinolíticos , Humanos , Fibrinolíticos/uso terapêutico , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Transfusão de Sangue , Hemorragia/etiologia , Incidência , Sulfadiazina , Estudos Retrospectivos
7.
Br J Haematol ; 202(1): 135-146, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37062931

RESUMO

Frequent germline mutations of HAVCR2, recently identified in subcutaneous panniculitis-like T-cell lymphoma (SPTCL), are associated with an increased risk of hemophagocytic lymphohistiocytosis (HLH). However, SPTCL-HLH represents a challenge because of the difficulties in treatment with poor survival. Its malignant nature, specifically harbouring HAVCR2 mutations, has also been questioned. To better understand its pathology and treatment, we analysed the clinical data of six patients diagnosed at our centre. The median age at onset was 10.5 years (range, 0.8-12.4). Five patients presented with skin lesions of subcutaneous nodules/plaques and/or ulceration. All patients developed HLH; notably, one infant only had HLH without skin involvement. Histopathologically, only two patients were diagnosed with SPTCL and three were reported as panniculitis with no sufficient evidence of lymphoma. Genetically, germline homozygous mutation of HAVCR2 (p.Y82C) was identified in all patients, with a median diagnosis time of 4.6 months. All patients initially received corticosteroids, immunosuppressants or chemotherapy, achieving unfavourable responses. Strikingly, they responded well to ruxolitinib targeting inflammatory cytokines, allowing rapid disease resolution and/or long-term maintenance of remission. The excellent efficacy of ruxolitinib highlights this disease as an inflammatory condition instead of neoplastic nature and indicates novel agents targeting key inflammatory pathways as an encouraging approach for this disease entity.


Assuntos
Linfo-Histiocitose Hemofagocítica , Paniculite , Criança , Pré-Escolar , Humanos , Lactente , Mutação em Linhagem Germinativa , Receptor Celular 2 do Vírus da Hepatite A/genética , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/complicações , Paniculite/tratamento farmacológico , Paniculite/genética
8.
Small ; 19(29): e2205768, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37035943

RESUMO

Humans perceive the world through five senses, of which olfaction is the oldest evolutionary sense that enables the detection of chemicals in the external environment. Recent progress in bioinspired electronics has boosted the development of artificial sensory systems. Here, a biohybrid olfactory system is proposed by integrating living mammals with implantable flexible neural electrodes, to employ the outstanding properties of mammalian olfactory system. In olfactory perception, the peripheral organ-olfactory epithelium (OE) projects axons into the olfactory relay station-olfactory bulb (OB). The olfactory information encoded in the neural activity is recorded from both OE and OB simultaneously using flexible neural electrodes. Results reveal that spontaneous slow oscillations (<12 Hz) in both OE and OB closely follow respiration. This respiration-locked rhythm modulates the amplitude of fast oscillations (>20 Hz), which are associated with odor perception. Further, by extracting the characteristics of odor-evoked oscillatory signals, responses of different odors are identified and classified with 80% accuracy. This study demonstrates for the first time that the flexible electrode enables chronic stable electrophysiological recordings of the peripheral and central olfactory system in vivo. Overall, the method provides a novel neural interface for olfactory biosensing and cognitive processing.


Assuntos
Condutos Olfatórios , Olfato , Animais , Humanos , Condutos Olfatórios/fisiologia , Olfato/fisiologia , Bulbo Olfatório/fisiologia , Odorantes , Percepção , Mamíferos
9.
J Transl Med ; 21(1): 721, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37838657

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) development may be associated with tumor immune escape. This study explores whether the CHI3L1/MAF/CTLA4/S100A4 axis affects immune escape in TNBC through interplay with triple-negative breast cancer stem cells (TN-BCSCs). OBJECTIVE: The aim of this study is to utilize single-cell transcriptome sequencing (scRNA-seq) to uncover the molecular mechanisms by which the CHI3L1/MAF/CTLA4 signaling pathway may mediate immune evasion in triple-negative breast cancer through the interaction between tumor stem cells (CSCs) and immune cells. METHODS: Cell subsets in TNBC tissues were obtained through scRNA-seq, followed by screening differentially expressed genes in TN-BCSCs and B.C.s (CD44+ and CD24-) and predicting the transcription factor regulated by CHI3L1. Effect of CHI3L1 on the stemness phenotype of TNBC cells investigated. Effects of BCSCs-231-derived CHI3L1 on CTLA4 expression in T cells were explored after co-culture of BCSCs-231 cells obtained from microsphere culture of TN-BCSCs with T cells. BCSCs-231-treated T cells were co-cultured with CD8+ T cells to explore the resultant effect on T cell cytotoxicity. An orthotopic B.C. transplanted tumor model in mice with humanized immune systems was constructed, in which the Role of CHI3L1/MAF/CTLA4 in the immune escape of TNBC was explored. RESULTS: Eight cell subsets were found in the TNBC tissues, and the existence of TN-BCSCs was observed in the epithelial cell subset. CHI3L1 was related to the stemness phenotype of TNBC cells. TN-BCSC-derived CHI3L1 increased CTLA4 expression in T cells through MAF, inhibiting CD8+ T cell cytotoxicity and inducing immunosuppression. Furthermore, the CTLA4+ T cells might secrete S100A4 to promote the stemness phenotype of TNBC cells. CONCLUSIONS: TN-BCSC-derived CHI3L1 upregulates CTLA4 expression in T cells through MAF, suppressing the function of CD8+ T cells, which promotes the immune escape of TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/genética , Antígeno CTLA-4/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Transdução de Sinais , Células-Tronco Neoplásicas/patologia , Linhagem Celular Tumoral , Proteína 1 Semelhante à Quitinase-3/metabolismo
10.
Opt Lett ; 48(3): 554-557, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723529

RESUMO

Optical waveguides prepared by femtosecond laser direct writing have birefringent properties, which can affect polarization encoding and entanglement on chips. Here, we first propose a shape-stress dual compensation fabrication scheme to decrease birefringence. Ultralow birefringent waveguides (1 × 10-9) were obtained by controlling the cross sectional shape of the main waveguide and adjusting the position of the auxiliary lines. In addition, we prepared polarization-independent directional coupler and demonstrated the evolution of polarization-independent waveguide array with different polarized light. In the future, ultralow birefringent waveguides will be widely applied in polarization encoding and entangled quantum photonic integrated circuits.

11.
Pharmacol Res ; 198: 106991, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37984505

RESUMO

Carrimycin is a potential immune-regulating agent for sepsis in patients with tumors. In this study, we investigated its effects on inflammation and immune function in tumor patients with sepsis. In total, 120 participants were randomized to receive either carrimycin treatment (400 mg/day) (n = 62) or placebo (n = 58) for 7 days. The primary outcomes were immune-related indicators. Subsequently, patients were stratified into two subgroups (CD4 < 38.25% and CD8 < 25.195%). Ninety-nine participants were analyzed: 47 and 52 in the carrimycin and placebo groups, respectively. HLA-DR levels were rapidly increased in the carrimycin group; however, the placebo group initially experienced a decline in HLA-DR level at 1 day after administration. In the subgroup with CD4 < 38.25%, the carrimycin group exhibited significantly higher HLA-DR levels than the placebo group (2.270, P = 0.023) 1 day after administration and the degree of increase in HLA-DR in the carrimycin group was higher than that in the placebo group (2.057, P = 0.040). In the CD8 < 25.195% subgroup, the carrimycin group demonstrated significantly higher levels of CD8+ T cells than the placebo group at 3 (2.300,P = 0.027) and 5 (2.106, P = 0.035) days after administration. Carrimycin intervention led to significant reductions in the SOFA, APACHE II, PCT, and CRP levels. No adverse events were observed. In tumor patients with sepsis, particularly in those experiencing immunological suppression, carrimycin effectively regulates immune responses by increasing HLA-DR and CD8+ T cell levels and plays an anti-infective role, reducing disease severity. (Chictr.org.cn, ID Number: ChiCTR2000032339).


Assuntos
Neoplasias , Sepse , Humanos , Linfócitos T CD8-Positivos , Biomarcadores , Antígenos HLA-DR , Sepse/tratamento farmacológico , Inflamação/tratamento farmacológico , Imunidade , Neoplasias/tratamento farmacológico , Método Duplo-Cego
12.
J Chem Inf Model ; 63(8): 2345-2359, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-37000044

RESUMO

The n-octanol/buffer solution distribution coefficient at pH = 7.4 (log D7.4) is an indicator of lipophilicity, and it influences a wide variety of absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties and druggability of compounds. In log D7.4 prediction, graph neural networks (GNNs) can uncover subtle structure-property relationships (SPRs) by automatically extracting features from molecular graphs that facilitate the learning of SPRs, but their performances are often limited by the small size of available datasets. Herein, we present a transfer learning strategy called pretraining on computational data and then fine-tuning on experimental data (PCFE) to fully exploit the predictive potential of GNNs. PCFE works by pretraining a GNN model on 1.71 million computational log D data (low-fidelity data) and then fine-tuning it on 19,155 experimental log D7.4 data (high-fidelity data). The experiments for three GNN architectures (graph convolutional network (GCN), graph attention network (GAT), and Attentive FP) demonstrated the effectiveness of PCFE in improving GNNs for log D7.4 predictions. Moreover, the optimal PCFE-trained GNN model (cx-Attentive FP, Rtest2 = 0.909) outperformed four excellent descriptor-based models (random forest (RF), gradient boosting (GB), support vector machine (SVM), and extreme gradient boosting (XGBoost)). The robustness of the cx-Attentive FP model was also confirmed by evaluating the models with different training data sizes and dataset splitting strategies. Therefore, we developed a webserver and defined the applicability domain for this model. The webserver (http://tools.scbdd.com/chemlogd/) provides free log D7.4 prediction services. In addition, the important descriptors for log D7.4 were detected by the Shapley additive explanations (SHAP) method, and the most relevant substructures of log D7.4 were identified by the attention mechanism. Finally, the matched molecular pair analysis (MMPA) was performed to summarize the contributions of common chemical substituents to log D7.4, including a variety of hydrocarbon groups, halogen groups, heteroatoms, and polar groups. In conclusion, we believe that the cx-Attentive FP model can serve as a reliable tool to predict log D7.4 and hope that pretraining on low-fidelity data can help GNNs make accurate predictions of other endpoints in drug discovery.


Assuntos
Descoberta de Drogas , Halogênios , 1-Octanol , Aprendizagem , Redes Neurais de Computação
13.
Cell Biochem Funct ; 41(7): 752-766, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37555645

RESUMO

MicroRNAs (miRNAs) are a class of noncoding RNAs that occupy a significant role in biological processes as important regulators of intracellular homeostasis. First, we will discuss the biological genesis and functions of the miR-302/367 cluster, including miR-302a, miR-302b, miR-302c, miR-302d, and miR-367, as well as their roles in physiologically healthy tissues. The second section of this study reviews the progress of the miR-302/367 cluster in the treatment of cancer, inflammation, and diseases associated with aging. This cluster's aberrant expression in cells and/or tissues exhibits similar or different effects in various diseases through molecular mechanisms such as proliferation, apoptosis, cycling, drug resistance, and invasion. This article also discusses the upstream and downstream regulatory networks of miR-302/367 clusters and their related mechanisms. Particularly because studies on the upstream regulatory molecules of miR-302/367 clusters, which include age-related macular degeneration, myocardial infarction, and cancer, have become more prevalent in recent years. MiR-302/367 cluster can be an important therapeutic target and the use of miRNAs in combination with other molecular markers may improve diagnostic or therapeutic capabilities, providing unique insights and a more dynamic view of various diseases. It is noted that miRNAs can be an important bio-diagnostic target and offer a promising method for illness diagnosis, prevention, and treatment.

14.
Ecotoxicol Environ Saf ; 260: 115068, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257348

RESUMO

The present study systematically analyzed and evaluated the variations in chemical speciation, pollution assessment, and source identification of heavy metals in sediments of Huangpu River. The methods employed included heavy metal concentration, chemical speciation and Cu isotopic compositions analysis. Results showed that the chemical speciation of sediment-bound heavy metals, characterized by significant seasonal variation, shifted from non-residual fractions dominating in spring and summer to residual fractions dominating in autumn and winter. Precipitation was identified as an important factor influencing the chemical speciation of sediment-bound heavy metals. Furthermore, ratio of the secondary phase to the primary phase, RSP (=Cnon-residual/Cresidual) values in Huangpu River sediments were higher than 1 in spring and summer, indicating that sediment-bound heavy metals in Huangpu River were mainly composed of non-residual fractions and could potentially be released into the river water. Principal component analysis (PCA) revealed that navigation, traffic, agricultural, and industrial activities could be the potential sources of heavy metal pollution. Notably, the δ65Cu values in Huangpu River sediments were observed to be isotopically lighter (from -0.37 to +0.18 ‰), suggesting that navigation might be the primary pollution source. These results will not only provide guidance in reducing heavy metal concentrations, but also serve as a crucial basis for policy making regarding heavy metal control.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Rios/química , Estações do Ano , China , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Medição de Risco , Metais Pesados/análise
15.
Molecules ; 28(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37110828

RESUMO

Lobophorins (LOBs) are a growing family of spirotetronate natural products with significant cytotoxicity, anti-inflammatory, and antibacterial activities. Herein, we report the transwell-based discovery of Streptomyces sp. CB09030 from a panel of 16 in-house Streptomyces strains, which has significant anti-mycobacterial activity and produces LOB A (1), LOB B (2), and LOB H8 (3). Genome sequencing and bioinformatic analyses revealed the potential biosynthetic gene cluster (BGC) for 1-3, which is highly homologous with the reported BGCs for LOBs. However, the glycosyltransferase LobG1 in S. sp. CB09030 has certain point mutations compared to the reported LobG1. Finally, LOB analogue 4 (O-ß-D-kijanosyl-(1→17)-kijanolide) was obtained through an acid-catalyzed hydrolysis of 2. Compounds 1-4 showed different antibacterial activities against Mycobacterium smegmatis and Bacillus subtilis, which revealed the varying roles of different sugars in their antibacterial activities.


Assuntos
Streptomyces , Streptomyces/química , Macrolídeos/química , Antibacterianos/química , Sequência de Bases , Família Multigênica
16.
Anal Chem ; 94(19): 6976-6985, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35503097

RESUMO

The past decade has witnessed tremendous progress achieved in taste research, while few studies focus on interactions among taste compounds. Indeed, sweeteners and acidulants are commonly used food additives, and sweet-sour mixtures always provide improved tastes. For example, sensory studies have shown that sourness suppresses sweetness. However, the degree of sweetness suppression by sourness is difficult to evaluate quantitatively and objectively. Therefore, we propose a biohybrid tongue that is constructed by integrating mammalian gustatory epithelium with a microelectrode array chip. The taste quality and intensity information is coded in time-frequency patterns of local field potential. Different response patterns evoked by sweet and sour stimuli are observed, and the response is dose-dependent. Then, interaction effects of sourness against sweetness are quantified. The results indicate that suppression of sweetness by sourness occurs by increasing sourness concentrations. In summary, this study provides a powerful new tool for quantitative evaluation of sweet, sour, and their binary taste interactions that mimic the mammalian taste system.


Assuntos
Edulcorantes , Paladar , Animais , Mamíferos , Paladar/fisiologia , Língua
17.
Opt Lett ; 47(4): 921-924, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35167559

RESUMO

In this study, a hybrid method for high-quality rapid drilling of transparent hard materials which combines femtosecond laser (fs-laser) Bessel beam modifying materials and selective wet etching is presented. Using this method, micro-holes with no taper of different sizes (from 10 to 35 µm) and shapes (square, triangle, circular, and pentagram) are fabricated. Bessel beams of different lengths can be generated flexibly by loading different computer-generated holograms (CGHs) into the spatial light modulator (SLM) and the maximum length of light interacting with materials can reach 320 µm, leading to a reduction of the laser scanning time by two orders of magnitude. Moreover, a set of three-dimensional multi-layer submicron through-holes in crystal materials is also realized, with an aspect ratio of more than 1000 for each hole. These results indicate that this method has broad application potential in chip packaging, aviation manufacturing, single particle catalysis, and other fields.

18.
Anticancer Drugs ; 33(7): 632-641, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35324530

RESUMO

Leucine zipper/EF hand-containing transmembrane-1 (LETM1) is an important mitochondrial protein, while its function in endometrial cancer remains unknown. This study aimed to explore the function of LETM1 in endometrial cancer and reveal the underlying mechanisms involving carboxy-terminal modulator protein (CTMP). Immunohistochemistry was performed to detect the expression of LETM1 and CTMP in normal, atypical hyperplastic and endometrial cancer endometrial tissues. LETM1 and CTMP were silenced in two endometrial cancer cell lines (ISK and KLE), which were verified by western blot. Cell viability, colony number, migration and invasion were detected by cell counting kit-8, colony formation, wound healing and trans-well assays, respectively. A xenograft mouse model was established to determine the antitumor potential of LETM1/CTMP silencing in vivo . In addition, CTMP was overexpressed to evaluate its regulatory relationship with LETM1 in endometrial cancer cells. The expression of LETM1 and CTMP proteins were higher in endometrial cancer tissues than atypical hyperplastic tissues and were higher in atypical hyperplastic tissues than normal tissues. LETM1 and CTMP were also upregulated in ISK and KLE cells. Silencing of LETM1 or CTMP could decrease the viability, colony number, migration and invasion of endometrial cancer cells and the weight and volume of tumor xenografts. In addition, CTMP was downregulated by LETM1 silencing in KLE cells, and its overexpression enhanced the malignant characteristics of si-LETM1-transfected KLE cells. Silencing of LETM1 inhibits the malignant progression of endometrial cancer through downregulating CTMP.


Assuntos
Neoplasias do Endométrio , Proteínas Mitocondriais , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Transporte , Linhagem Celular Tumoral , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/genética , Feminino , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Nucleotídeos Cíclicos , Palmitoil-CoA Hidrolase/metabolismo , Timidina Monofosfato
19.
BMC Cardiovasc Disord ; 22(1): 372, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35965341

RESUMO

BACKGROUND: The atherogenic index of plasma (AIP) is a predictor for cardiovascular diseases (CVD), while hyperuricemia is an independent risk factor for a variety of CVD. Apolipoprotein AI has been found to be a protective factor for CVD. However, the role of APO AI in the association between plasma uric acid and AIP among healthy Chinese people needs to be further explored. AIMS: To evaluate the relationship between blood uric acid and AIP level in healthy Chinese people. To evaluate the relationship between blood uric acid and Apolipoprotein AI in healthy Chinese people. METHOD: A total of 3501 normal and healthy subjects who had physical examinations were divided into the hyperuricemia (HUA) group and the normouricemia (NUA) group. RESULT: The AIP of HUA group was significantly higher than that of NUA group [0.17±0.30 vs. -0.08±0.29]. Apo AI (1.33 ± 0.21 vs. 1.47 ± 0.26 g/l) and HDL-c (1.12 ± 0.27 vs. 1.36 ± 0.33 mmol/l) were significantly lower in the HUA group than in the NUA group. LDL-C (2.81 ± 0.77 vs. 2.69 ± 0.73 mmol/l), Apo B (0.96 ± 0.20 vs. 0.89 ± 0.20 g/l), FBG (5.48 ± 0.48 vs. 5.36 ± 0.48 mmol/l) and HOMA-IR [2.75 (1.92-3.91) vs. 2.18 (1.50-3.12)] was significantly higher in HAU group than the NUA group. Increases in plasma UA were associated with increases in AIP (ß = 0.307, p < 0.01) and decreases in Apo AI (ß = - 0.236, p < 0.01). CONCLUSION: Hyperuricemia is an independent risk factor for high AIP level. Inhibition of Apolipoprotein AI may be one of the mechanisms of UA which is involved in the progression of cardiovascular disease.


Assuntos
Doenças Cardiovasculares , Hiperuricemia , Apolipoproteína A-I , China/epidemiologia , Estudos Transversais , Humanos , Hiperuricemia/diagnóstico , Ácido Úrico
20.
Nature ; 531(7594): 348-51, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26983539

RESUMO

Quantum computing is an emerging area within the information sciences revolving around the concept of quantum bits (qubits). A major obstacle is the extreme fragility of these qubits due to interactions with their environment that destroy their quantumness. This phenomenon, known as decoherence, is of fundamental interest. There are many competing candidates for qubits, including superconducting circuits, quantum optical cavities, ultracold atoms and spin qubits, and each has its strengths and weaknesses. When dealing with spin qubits, the strongest source of decoherence is the magnetic dipolar interaction. To minimize it, spins are typically diluted in a diamagnetic matrix. For example, this dilution can be taken to the extreme of a single phosphorus atom in silicon, whereas in molecular matrices a typical ratio is one magnetic molecule per 10,000 matrix molecules. However, there is a fundamental contradiction between reducing decoherence by dilution and allowing quantum operations via the interaction between spin qubits. To resolve this contradiction, the design and engineering of quantum hardware can benefit from a 'bottom-up' approach whereby the electronic structure of magnetic molecules is chemically tailored to give the desired physical behaviour. Here we present a way of enhancing coherence in solid-state molecular spin qubits without resorting to extreme dilution. It is based on the design of molecular structures with crystal field ground states possessing large tunnelling gaps that give rise to optimal operating points, or atomic clock transitions, at which the quantum spin dynamics become protected against dipolar decoherence. This approach is illustrated with a holmium molecular nanomagnet in which long coherence times (up to 8.4 microseconds at 5 kelvin) are obtained at unusually high concentrations. This finding opens new avenues for quantum computing based on molecular spin qubits.

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