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1.
Nat Commun ; 15(1): 3310, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632249

RESUMO

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is a devastating disease that is present in all major soybean-producing regions. The limited availability of resistant germplasm has resulted in a scarcity of commercial soybean cultivars that are resistant to the disease. To date, only the Chinese soybean landrace SX6907 has demonstrated an immune response to ASR. In this study, we present the isolation and characterization of Rpp6907-7 and Rpp6907-4, a gene pair that confer broad-spectrum resistance to ASR. Rpp6907-7 and Rpp6907-4 encode atypic nucleotide-binding leucine-rich repeat (NLR) proteins that are found to be required for NLR-mediated immunity. Genetic analysis shows that only Rpp6907-7 confers resistance, while Rpp6907-4 regulates Rpp6907-7 signaling activity by acting as a repressor in the absence of recognized effectors. Our work highlights the potential value of using Rpp6907 in developing resistant soybean cultivars.


Assuntos
Phakopsora pachyrhizi , Glycine max , Genes de Plantas , Doenças das Plantas/genética
2.
Inflammopharmacology ; 32(2): 1025-1038, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38308795

RESUMO

BACKGROUND: This study aimed to evaluate the immunogenicity and safety of different types of poliovirus vaccines. METHODS: A randomized, blinded, single-center, parallel-controlled design was employed, and 360 infants aged ≥ 2 months were selected as study subjects. They were randomly assigned to bOPV group (oral Sabin vaccine) and sIPV group (Sabin strain inactivated polio vaccine), with 180 infants in each group. Adverse reaction events in the vaccinated subjects were recorded. The micro-neutralization test using cell culture was conducted to determine the geometric mean titer (GMT) of neutralizing antibodies against poliovirus types I, II, and III in different groups, and the seroconversion rates were calculated. RESULTS: Both groups exhibited a 100% seropositivity rate after booster immunization. The titers of neutralizing antibodies for the three types were predominantly distributed within the range of 1:128 to 1:512. The fold increase of type I antibodies differed markedly between the two groups (P < 0.05). Moreover, the fold increase of type II and type III antibodies for poliovirus differed slightly between the two groups (P > 0.05). The fourfold increase rate in sIPV group was drastically superior to that in bOPV group (P < 0.05). When comparing the post-immunization GMT levels of type I antibodies in individuals who completed the full course of spinal muscular atrophy vaccination, bOPV group showed greatly inferior levels to sIPV group (P < 0.05). For type II and type III antibodies, individuals in bOPV group demonstrated drastically superior post-immunization GMT levels to those in sIPV group (P < 0.05). The incidence of adverse reactions between the bOPV and sIPV groups differed slightly (P > 0.05). CONCLUSION: These findings indicated that both the oral vaccine and inactivated vaccine had good safety and immunogenicity in infants aged ≥ 2 months. The sIPV group generated higher levels of neutralizing antibodies in serum, particularly evident in the post-immunization GMT levels for types II and III.


Assuntos
Poliomielite , Poliovirus , Humanos , Lactente , Anticorpos Neutralizantes , Anticorpos Antivirais , Esquemas de Imunização , Poliomielite/prevenção & controle , Poliomielite/induzido quimicamente , Vacina Antipólio Oral/efeitos adversos , Observação
3.
Chem Commun (Camb) ; 60(6): 682-685, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38054857

RESUMO

Efficient conversion of C1 molecules into multicarbon oxygenates is a promising avenue for energy storage. Herein, we synthesize adjustable alkanoic acids/alcohols from formate C1 molecules via a hydrothermal reaction without any metal catalyst participation. This is achieved via HCO* and HCOO- nonsymmetric C-C coupling by alkali catalysis in aqueous medium.

4.
Angew Chem Int Ed Engl ; 62(41): e202305331, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37173278

RESUMO

Viscosity is an extremely important property for ion transport and wettability of electrolytes. Easy access to viscosity values and a deep understanding of this property remain challenging yet critical to evaluating the electrolyte performance and tailoring electrolyte recipes with targeted properties. We proposed a screened overlapping method to efficiently compute the viscosity of lithium battery electrolytes by molecular dynamics simulations. The origin of electrolyte viscosity was further comprehensively probed. The viscosity of solvents exhibits a positive correlation with the binding energy between molecules, indicating viscosity is directly correlated to intermolecular interactions. Salts in electrolytes enlarge the viscosity significantly with increasing concentrations while diluents serve as the viscosity reducer, which is attributed to the varied binding strength from cation-anion and cation-solvent associations. This work develops an accurate and efficient method for computing the electrolyte viscosity and affords deep insight into viscosity at the molecular level, which exhibits the huge potential to accelerate advanced electrolyte design for next-generation rechargeable batteries.

5.
Molecules ; 28(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36903586

RESUMO

A novel aptamer-based fluorescent-sensing platform with a triple-helix molecular switch (THMS) was proposed as a switch for detecting the arsenic(III) ion. The triple helix structure was prepared by binding a signal transduction probe and arsenic aptamer. Additionally, the signal transduction probe labeled with fluorophore (FAM) and quencher (BHQ1) was employed as a signal indicator. The proposed aptasensor is rapid, simple and sensitive, with a limit of detection of 69.95 nM. The decrease in peak fluorescence intensity shows a linear dependence, with the concentration of As(III) in the range of 0.1 µM to 2.5 µM. The whole detection process takes 30 min. Moreover, the THMS-based aptasensor was also successfully used to detect As(III) in a real sample of Huangpu River water with good recoveries. The aptamer-based THMS also presents distinct advantages in stability and selectivity. The proposed strategy developed herein can be extensively applied in the field of food inspection.


Assuntos
Aptâmeros de Nucleotídeos , Arsênio , Técnicas Biossensoriais , Limite de Detecção , Corantes Fluorescentes/química , Aptâmeros de Nucleotídeos/química
6.
Methods Mol Biol ; 2653: 39-52, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36995618

RESUMO

Currently methods for generating soybean edited lines are time-consuming, inefficient, and limited to certain genotypes. Here we describe a fast and highly efficient genome editing method based on CRISPR-Cas12a nuclease system in soybean. The method uses Agrobacterium-mediated transformation to deliver editing constructs and uses aadA or ALS genes as selectable marker. It only takes about 45 days to obtain greenhouse-ready edited plants at higher than 30% transformation efficiency and 50% editing rate. The method is applicable to other selectable markers including EPSPS and has low transgene chimera rate. The method is also genotype-flexible and has been applied to genome editing of several elite soybean varieties.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Glycine max/genética , Glycine max/metabolismo , Endonucleases/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Genoma de Planta/genética
7.
Ann Transl Med ; 11(2): 123, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36819540

RESUMO

Background: To explore the key genes, biological functions, and pathways of empagliflozin in the treatment of type 2 diabetes mellitus (T2DM) through network pharmacology. Methods: The TCMSP (a traditional Chinese medicine system pharmacology database and analysis platform) was used to screen empagliflozin's active components and targets. The target genes of T2DM were screened according to the GeneCards and OMIM databases, and a Venn diagram was constructed to obtain the target for T2DM treatment. Cytoscape 3.7.2 software was adopted to construct the drug-component-target-disease network. Functional annotation of Gene Ontology (GO) and enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed using R software. Results: Target genes with a probability >0 were selected, among which Compound 012, Compound 060, Compound 093, Compound 111, and Compound 119 Swiss Target Prediction suggested that no similar active substances or predictable target genes were found. A "compound-target gene-disease" network was constructed, in which SLC5A2, SLC5A1, SLC5A4, SLC5A11, ADK, and ADORA2A were the core genes of T2DM. The key factors of the GO summary map included chemical reaction, membrane organelle, protein binding, and so on. The KEGG pathway summary map included the AMPK pathway, insulin resistance, the MAPK pathway, longevity-related pathway regulation, and so on. The top 10 pathways were endocrine resistance, the NF-κB signaling pathway, the HIF-1 signaling pathway, apoptosis, cell senescence, the Ras signaling pathway, the MAPK signaling pathway, the FoxO signaling pathway, the P13K-Akt signaling pathway, and the p53 signaling pathway. The binding of active compounds to key proteins was verified based on the Swiss Dock database, and the molecular docking of 193 bioactive compounds was finally verified. Among them, SLC5A2, SLC5A1, LDHA, KLK1, KLF5, and GSTP1 had better binding to the protein molecules. Conclusions: Empagliflozin may regulate the targets of SLC5A2, SLC5A1, LDHA, KLK1, KLF5, and GSTP1. There are numerous ways of treating T2DM with empagliflozin, including by regulating apoptosis, cell aging, as well as the NF-κB, HIF-1HIF-1, Ras, MAPK, FoxO, P13K-Akt, and p53 pathways.

8.
J Chem Phys ; 158(1): 014702, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36610967

RESUMO

Ion transport in solids is a key topic in solid-state ionics. It is critical but challenging to understand the relationship between material structures and ion transport. Nanochannels in crystals provide ion transport pathways, which are responsible for the fast ion transport in fast lithium (Li)-ion conductors. The controlled synthesis of carbon nanotubes (CNTs) provides a promising approach to artificially regulating nanochannels. Herein, the CNTs with a diameter of 5.5 Å are predicted to exhibit an ultralow Li-ion diffusion barrier of about 10 meV, much lower than those in routine solid electrolyte materials. Such a characteristic is attributed to the similar chemical environment of a Li ion during its diffusion based on atomic and electronic structure analyses. The concerted diffusion of Li ions ensures high ionic conductivities of CNTs. These results not only reveal the immense potential of CNTs for fast Li-ion transport but also provide a new understanding for rationally designing solid materials with high ionic conductivities.

9.
Funct Integr Genomics ; 23(1): 29, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36604355

RESUMO

ThE present work focused on exploring Girdin expression within gastric cancer (GC), examining the effect of Girdin on the cell phenotype of GC, and clarifying the underlying mechanisms. Girdin expression in GC samples was identified by immunohistochemistry (IHC) and quantitative real-time PCR (qRT-PCR) assays. Girdin-targeting siRNAs were transfected into GC cells; later, we examined GC cell proliferation, migration, invasion, and apoptosis, respectively. Additionally, the protein expression was examined through Western blotting assay. Moreover, the tumor implantation experiment was conducted for examining Girdin knockdown in vivo. The results showed that Girdin expression elevated within GC samples, which was associated with the dismal prognostic outcome. Girdin knockdown suppressed GC cell proliferation, migration, and invasion, and enhanced apoptosis and cell cycle arrest. Girdin promoted the phosphorylation of AKT, GSK3ß, and ß-catenin. Moreover, Girdin inhibited the phosphorylation of ß-catenin. Girdin suppressed cell apoptosis and stimulated cell migration and invasion, while AKT inhibitor (MK2206) treatment reversed the effect of Girdin overexpression, and GSK3ß inhibitor (CHIR99021) treatment enhanced the effect of Girdin overexpression on GC cells. Besides, Girdin delayed tumor growth in vivo. In conclusion, Girdin was abnormally expressed in GC samples, which promoted the development of GC by regulating AKT/GSK3ß/ß-catenin signaling.


Assuntos
Proteínas dos Microfilamentos , Proteínas Proto-Oncogênicas c-akt , Neoplasias Gástricas , Proteínas de Transporte Vesicular , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Oncogenes , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo
10.
Sci Adv ; 8(47): eadd5189, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36427308

RESUMO

In the pursuit of energy-dense all-solid-state lithium batteries (ASSBs), Li-rich Mn-based oxide (LRMO) cathodes provide an exciting path forward with unexpectedly high capacity, low cost, and excellent processibility. However, the cause for LRMO|solid electrolyte interfacial degradation remains a mystery, hindering the application of LRMO-based ASSBs. Here, we first reveal that the surface oxygen instability of LRMO is the driving force for interfacial degradation, which severely blocks the interfacial Li-ion transport and triggers fast battery failure. By replacing the charge compensation of surface oxygen with sulfite, the overoxidation and interfacial degradation can be effectively prevented, therefore achieving a high specific capacity (~248 mAh g-1, 1.1 mAh cm-2; ~225 mAh g-1, 2.9 mAh cm-2) and excellent long-term cycling stability of >300 cycles with 81.2% capacity retention at room temperature. These findings emphasize the importance of irreversible anion reactions in interfacial failure and provide fresh insights into constructing stable interfaces in LRMO-based ASSBs.

11.
Sci Adv ; 8(45): eadd0510, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36351020

RESUMO

The fundamental understanding of the elusive evolution behavior of the buried solid-solid interfaces is the major barrier to exploring solid-state electrochemical devices. Here, we uncover the interfacial void evolution principles in solid-state batteries, build a solid-state void nucleation and growth model, and make an analogy with the bubble formation in liquid phases. In solid-state lithium metal batteries, the lithium stripping-induced interfacial void formation determines the morphological instabilities that result in battery failure. The void-induced contact loss processes are quantified in a phase diagram under wide current densities ranging from 1.0 to 10.0 milliamperes per square centimeter by rational electrochemistry calculations. The in situ-visualized morphological evolutions reveal the microscopic features of void defects under different stripping circumstances. The electrochemical-morphological relationship helps to elucidate the current density- and areal capacity-dependent void nucleation and growth mechanisms, which affords fresh insights on understanding and designing solid-solid interfaces for advanced solid-state batteries.

12.
Angew Chem Int Ed Engl ; 61(52): e202210859, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36314987

RESUMO

Advanced electrolyte design is essential for building high-energy-density lithium (Li) batteries, and introducing anions into the Li+ solvation sheaths has been widely demonstrated as a promising strategy. However, a fundamental understanding of the critical role of anions in such electrolytes is very lacking. Herein, the anionic chemistry in regulating the electrolyte structure and stability is probed by combining computational and experimental approaches. Based on a comprehensive analysis of the lowest unoccupied molecular orbitals, the solvents and anions in Li+ solvation sheaths exhibit enhanced and decreased reductive stability compared with free counterparts, respectively, which agrees with both calculated and experimental results of reduction potentials. Accordingly, new strategies are proposed to build stable electrolytes based on the established anionic chemistry. This work unveils the mysterious anionic chemistry in regulating the structure-function relationship of electrolytes and contributes to a rational design of advanced electrolytes for practical Li metal batteries.

13.
Angew Chem Int Ed Engl ; 61(52): e202211448, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36314993

RESUMO

Lithium-sulfur (Li-S) battery is strongly considered as one of the most promising energy storage systems due to its high theoretical energy density and low cost. However, the sluggish reduction kinetics from Li2 S4 to Li2 S during discharge hinders the practical application of Li-S batteries. Although various electrocatalysts have been proposed to improve the reaction kinetics, the electrocatalytic mechanism is unclear due to the complexity of sulfur reduction reactions (SRR). It is crucial to understand the electrocatalytic mechanism thoroughly for designing advanced electrocatalysts. Herein an electrocatalytic model is constructed to reveal the chemical mechanism of the SRR in Li-S batteries based on systematical density functional theory calculations, taking heteroatoms-doped carbon materials as an example. The adsorption energy of LiSy ⋅ (y=1, 2, or 3) radicals is used as a key descriptor to predict the reaction pathway, rate-determining step, and overpotential. A diagram for designing advanced electrocatalysts is accordingly constructed. This work establishes a theoretical model, which is an intelligent integration for probing the complicated SRR mechanisms and designing advanced electrocatalysts for high-performance Li-S batteries.

14.
Zhongguo Zhen Jiu ; 42(8): 857-62, 2022 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-35938327

RESUMO

OBJECTIVE: To observe the effect of staged acupuncture on serum irisin level, neurological deficit, balance ability and spasticity in patients with ischemic stroke. METHODS: Sixty patients with ischemic stroke were randomly divided into a staged acupuncture group and a routine acupuncture group, 30 cases in each group; another 30 healthy subjects were selected as a normal group. The patients with ischemic stroke were treated with aspirin (100 mg each time, once a day, changing to 50 mg for prophylactic dose after 4 weeks). The patients in the staged acupuncture group were treated with staged acupuncture (acupoints were selected according to the soft paralysis period, spasticity period and recovery period, sequelae period) and rehabilitation treatment, while the patients in the routine acupuncture group were treated with acupuncture of soft paralysis-period as the staged acupuncture group and rehabilitation treatment. All the treatment was given once a day, 5 times a week, 2 weeks as a course of treatment, and 4 consecutive courses of treatment were provided. Before treatment and at 2 weeks, 4 weeks, 6 weeks and 8 weeks into treatment, the serum irisin level was measured, and the scores of National Institutes of Health stroke scale (NIHSS), Fugl-Meyer assessment scale-balance (FM-B) and comprehensive spasticity scale (CSS) were compared, and the correlation between the serum irisin level and NIHSS and FM-B scores in the two groups was analyzed. RESULTS: Before treatment, the serum irisin levels in the two groups were lower than those in the normal group (P<0.01). Compared before treatment, the serum irisin levels and FM-B scores were increased (P<0.01), and the NIHSS scores were decreased at 2, 4, 6 and 8 weeks into treatment in the two groups (P<0.01). At 4, 6 and 8 weeks into treatment, in the staged acupuncture group, the serum irisin levels and FM-B scores were higher than those in the routine acupuncture group (P<0.01, P<0.05), and the NIHSS scores were lower than those in the routine acupuncture group (P<0.01). After treatment, the CSS scores in the two groups were increased first and then decreased. Compared before treatment, the CSS scores were increased at 2, 4, 6 and 8 weeks into treatment in the two groups (P<0.01). At 4, 6 and 8 weeks into treatment, the CSS scores in the staged acupuncture group were lower than those in the routine acupuncture group (P<0.01). The serum irisin level was negatively correlated with NIHSS score (r =-0.772, P =0.000), and positively correlated with FM-B score (r =0.675, P =0.000). CONCLUSION: The severity of neurological deficit and balance ability are related to serum irisin level in patients with ischemic stroke. The staged acupuncture could increase the serum irisin level, improve the neurological function, balance ability and spasticity in patients with ischemic stroke.


Assuntos
Terapia por Acupuntura , AVC Isquêmico , Reabilitação Neurológica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Fibronectinas , Humanos , Espasticidade Muscular , Paralisia/complicações , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
15.
Sci Adv ; 8(33): eabq3445, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35977021

RESUMO

The life span of lithium batteries as energy storage devices is plagued by irreversible interfacial reactions between reactive anodes and electrolytes. Occurring on polycrystal surface, the reaction process is inevitably affected by the surface microstructure of anodes, of which the understanding is imperative but rarely touched. Here, the effect of grain boundary of lithium metal anodes on the reactions was investigated. The reactions preferentially occur at the grain boundary, resulting in intercrystalline reactions. An aluminum (Al)-based heteroatom-concentrated grain boundary (Al-HCGB), where Al atoms concentrate at grain boundary, was designed to inhibit the intercrystalline reactions. In particular, the scalable preparation of Al-HCGB was demonstrated, with which the cycling performance of a pouch cell (355 Wh kg-1) was significantly improved. This work opens a new avenue to explore the effect of the surface microstructure of anodes on the interfacial reaction process and provides an effective strategy to inhibit reactions between anodes and electrolytes for long-life-span practical lithium batteries.

16.
Chem Rev ; 122(12): 10970-11021, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35576674

RESUMO

Rechargeable batteries have become indispensable implements in our daily life and are considered a promising technology to construct sustainable energy systems in the future. The liquid electrolyte is one of the most important parts of a battery and is extremely critical in stabilizing the electrode-electrolyte interfaces and constructing safe and long-life-span batteries. Tremendous efforts have been devoted to developing new electrolyte solvents, salts, additives, and recipes, where molecular dynamics (MD) simulations play an increasingly important role in exploring electrolyte structures, physicochemical properties such as ionic conductivity, and interfacial reaction mechanisms. This review affords an overview of applying MD simulations in the study of liquid electrolytes for rechargeable batteries. First, the fundamentals and recent theoretical progress in three-class MD simulations are summarized, including classical, ab initio, and machine-learning MD simulations (section 2). Next, the application of MD simulations to the exploration of liquid electrolytes, including probing bulk and interfacial structures (section 3), deriving macroscopic properties such as ionic conductivity and dielectric constant of electrolytes (section 4), and revealing the electrode-electrolyte interfacial reaction mechanisms (section 5), are sequentially presented. Finally, a general conclusion and an insightful perspective on current challenges and future directions in applying MD simulations to liquid electrolytes are provided. Machine-learning technologies are highlighted to figure out these challenging issues facing MD simulations and electrolyte research and promote the rational design of advanced electrolytes for next-generation rechargeable batteries.

17.
Sci Total Environ ; 828: 154440, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35276141

RESUMO

Food waste is a challenging biomass resource due to its high moisture content, low calorific value, and complex composition. Natural humification of animal and plant residues is highly related to microorganism activity, but natural hydrothermal conditions are also speculated to play a significant role. In this work, a novel method for the conversion of food waste into artificial humic acid (HAa) under hydrothermal conditions is proposed. The results revealed that an optimum HAa yield of 43.5% from food waste was successfully obtained at 215 °C for only 1 h. Detailed analyses, including elemental analysis (EA), X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR), and Fourier transform infrared (FT-IR) spectroscopy, showed that the produced HAa had similar structures and compositions with natural HA extracted from minerals. Moreover, the proteins contained in the food waste significantly promoted HA formation through the reaction of saccharides with amino acids, in which Maillard-like reactions were the key steps. These results not only provide experimental evidence for verifying the role of hydrothermal reactions in transforming food waste into humic acid but also provide insight into effective resource utilization of food waste.


Assuntos
Substâncias Húmicas , Eliminação de Resíduos , Animais , Alimentos , Substâncias Húmicas/análise , Minerais , Proteínas , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Chemistry ; 28(9): e202104293, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34932229

RESUMO

To investigate how remotely induced changes in ligand folding might affect catalysis by organometallic complexes, dynamic α-amino-iso-butyric acid (Aib) peptide foldamers bearing rhodium(I) N-heterocyclic carbene (NHC) complexes have been synthesized and studied. X-ray crystallography of a foldamer with an N-terminal azide and a C-terminal Rh(NHC)(Cl)(diene) complex showed a racemate with a chiral axis in the Rh(NHC) complex and a distorted 310 helical body. Replacing the azide with either one or two chiral L-α-methylvaline (L-αMeVal) residues gave diastereoisomeric foldamers that each possessed point, helical and axial chirality. NMR spectroscopy revealed an unequal ratio of diastereoisomers for some foldamers, indicating that the chiral conformational preference of the N-terminal residue(s) was relayed down the 1 nm helical body to the axially chiral Rh(NHC) complex. Although the remote chiral residue(s) did not affect the stereoselectivity of hydrosilylation reactions catalysed by these foldamers, these studies suggest a potential pathway towards remote conformational control of organometallic catalysts.


Assuntos
Compostos Heterocíclicos , Compostos Organometálicos , Ródio , Ácido Butírico , Catálise , Compostos Heterocíclicos/química , Irídio/química , Metano/análogos & derivados , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química , Ródio/química , Estereoisomerismo
19.
J Pharm Pharmacol ; 74(1): 124-130, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34559876

RESUMO

OBJECTIVE: To investigate whether the silent information regulator 1 (SIRT1) was involved in the protective effects of Ganoderma lucidum polysaccharides (GLP) against sepsis-induced cardiac dysfunction. METHODS: Lipopolysaccharide (LPS)-induced sepsis model was constructed in C57/BL6J mice. Mice were randomly divided into LPS + GLP + EX-527, LPS + EX-527, LPS + GLP, LPS or control group). The levels of serum inflammatory factor markers were examined by ELISA. H&E staining was performed to assess the inflammation. TUNEL staining and bromodeoxyuridine staining were used to observe cell apoptosis and proliferation, respectively. Expression of apoptosis and proliferation-related proteins was detected by western blot. KEY FINDINGS: GLP treatment could significantly increase the expression of SIRT1, reduce levels of serum inflammatory factors (TNF-α, IL-1α and IL-6) and inflammatory cells in mice heart tissue of sepsis models (all Ps < 0.01). Compared with LPS group, GLP treatment inhibited apoptosis and promoted proliferation of myocardial tissues (all Ps < 0.01). Besides, EX-527 (SIRT1 inhibitor) treatment could partially reverse the protective effects of GLP against sepsis-induced cardiac dysfunction (all Ps < 0.01). CONCLUSIONS: GLP might play a protective role in sepsis-induced cardiac dysfunction through regulating inflammatory response, apoptosis and proliferation via activating SIRT1. Therefore, GLP is expected to be a probable novel strategy for treatment of sepsis.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Cardiopatias , Polissacarídeos/farmacologia , Reishi , Sirtuína 1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cardiopatias/tratamento farmacológico , Cardiopatias/etiologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Substâncias Protetoras/farmacologia , Sepse/complicações , Transdução de Sinais/efeitos dos fármacos
20.
Proc Natl Acad Sci U S A ; 118(51)2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34911765

RESUMO

Abiotic CO2 reduction on transition metal minerals has been proposed to account for the synthesis of organic compounds in alkaline hydrothermal systems, but this reaction lacks experimental support, as only short-chain hydrocarbons (

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