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1.
Heliyon ; 10(3): e24809, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38318004

ABSTRACT

Objective: Animal models of brain and spinal cord metastases of non-small cell lung cancer were established through the intracranial injection of PC-9 Luc cells with a brain stereotaxic device. This method provides a reliable modeling method for studying brain and spinal cord metastases of non-small cell lung cancer. Methods: PC-9 Luc cells at logarithmic growth stage were injected into the skulls of 5-week-old BALB/c nude mice at different cell volumes (30 × 104, 80 × 104) and different locations (using anterior fontanel as a location point, 1 mm from the coronal suture, and 1.5 mm from the sagittal suture on the right upper and right lower side of the skull). After 1 week of cell inoculation, fluorescence signals of tumor cells in the brain and spinal were detected using the IVIS Xenogen Imaging system. After 4 weeks, brain and spinal tissues from the nude mice were harvested. Following paraffin-embedded sectioning, HE staining was performed on the tissues. Results: The fluorescence signals revealed that both brain and spinal cord metastasis occurred in the mice where the cells were injected at the lower right side of the skull. There was only brain metastasis in the nude mice injected with 30 × 104 cells at the upper right side of the skull. Both brain and spinal cord metastasis occurred in the nude mice injected with 80 × 104 cells. The HE staining revealed that both brain and spinal cord metastasis occurred in the mice injected with different amounts of PC-9 Luc cells, consistent with the results detected using the IVIS Xenogen Imaging system, thereby demonstrating the reliability of detecting fluorescent signals in vivo to determine tumor growth. Conclusion: It is a reliable method to establish the animal model of brain and spinal cord metastases of non-small cell lung cancer by injecting different quantities of cells from different positions with a brain stereotaxic device. The IVIS Xenogen Imaging system has high reliability in detecting the fluorescence signals of brain and spinal cord metastatic tumors.

2.
J Inflamm Res ; 17: 399-415, 2024.
Article in English | MEDLINE | ID: mdl-38260810

ABSTRACT

Background: Spontaneous intracerebral hemorrhage (ICH) is a subtype of stroke leading to high rates of morbidity and mortality in adults. Recent studies showed that immune and inflammatory responses might play essential roles in secondary brain injury. The purpose of this article was to provide a reference for further therapeutic strategies for ICH patients. Methods: GSE206971 and GSE216607 datasets from the gene expression omnibus (GEO) database were used to screen the highly immune-related differentally expressed genes (IRDEGs). We used the CIBERSORT algorithm to assess the level of immune signatures infiltration and got the possible function of IRDEGs which was analyzed through Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Protein-protein interaction (PPI) networks and six hub genes were identified in the Cytoscape plug-in. GSVA algorithm was performed to evaluate the potential pathways of six hub genes in ICH samples. The expression level of IL-7R chosen from six hub genes was further validated by Western blotting. The cell models of ICH were established for the research of IL-7/IL-7R signaling way. Results: A total of six hub genes (ITGAX, ITGAM, CCR2, CD28, SELL, and IL-7R) were identified. IL-7R was highly expressed in the mice ICH group, as shown by immunoblotting. Next, we constructed ICH cell models in RAW264.7 cells and BV2 cells. After treatment with IL-7, iNOS expression (M1 marker) was greatly inhibited while Arg-1(M2 marker) was enhanced, and it might function via the JAK3/STAT5 signaling pathway. Conclusion: The hypothesis is proposed that the IL-7/IL-7R signaling pathway might regulate the inflammatory process following ICH by regulating microglia polarization. Our study is limited and requires more in-depth experimental confirmation.

3.
BMC Public Health ; 24(1): 292, 2024 01 24.
Article in English | MEDLINE | ID: mdl-38267909

ABSTRACT

BACKGROUND: High rates of health inequalities and chronic non-communicable diseases exist amongst the prison population. This places people in and/or released from prison at heightened risk of multimorbidity, premature mortality, and reduced quality of life. Ensuring appropriate healthcare for people in prison to improve their health outcomes is an important aspect of social justice. This review examines the global literature on healthcare interventions to detect, monitor and manage chronic non-communicable diseases amongst the prison population and people recently released from prison. METHODS: Systematic searches of EMBASE, MEDLINE, CINAHL, Web of Science, Scopus, and the Cochrane Library were conducted and supplemented by citation searching and review of the grey literature. The literature searches attempted to identify all articles describing any healthcare intervention for adults in prison, or released from prison in the past 1 year, to detect, monitor, or manage any chronic non-communicable illness. 19,061 articles were identified, of which 1058 articles were screened by abstract and 203 articles were reviewed by full text. RESULTS: Sixty-five studies were included in the review, involving 18,311 participants from multiple countries. Most studies were quasi-experimental and/or low to moderate in quality. Numerous healthcare interventions were described in the literature including chronic disease screening, telemedicine, health education, integrated care systems, implementing specialist equipment and staff roles to manage chronic diseases in prisons, and providing enhanced primary care contact and/or support from community health workers for people recently released from prison. These interventions were associated with improvement in various measures of clinical and cost effectiveness, although comparison between different care models was not possible due to high levels of clinical heterogeneity. CONCLUSIONS: It is currently unclear which interventions are most effective at monitoring and managing chronic non-communicable diseases in prison. More research is needed to determine the most effective interventions for improving chronic disease management in prisons and how these should be implemented to ensure optimal success. Future research should examine interventions for addressing multimorbidity within prisons, since most studies tested interventions for a singular non-communicable disease.


Subject(s)
Noncommunicable Diseases , Prisons , Adult , Humans , Community Health Workers , Noncommunicable Diseases/therapy , Quality of Life
4.
Eur J Oral Sci ; 132(1): e12966, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38062539

ABSTRACT

The objective of this study was to determine the effects on the colour of adding increasing concentrations of graphene to orthodontic fixed retainer adhesives and to evaluate changes in optical transmission during light curing and the resultant degree of conversion. Two different types of adhesives commonly used for fixed retainers were investigated: A packable composite (Transbond) and a flowable composite (Transbond Supreme). Graphene was added to the adhesives in three different concentrations (0.01, 0.05, and 0.1 wt%). Adhesives without graphene addition were set as control groups. A Minolta colourimeter was used to measure the colour and translucency parameters. Irradiance transmitted during curing was quantified using MARC Light Collector. Fourier-transform infrared spectroscopy was used to record degree of conversion. Data were statistically analysed with the Student's t-test and one-way ANOVA with Tukey's tests (α = 0.05). The findings showed that incorporating graphene darkened the adhesive colour significantly and reduced translucency. As the graphene concentration reached 0.1 wt%, samples became opaque; yet, no adverse effect on degree of conversion was observed. The addition of graphene reduces optical transmission of lingual retainer adhesives; the effect increases with graphene concentration.


Subject(s)
Bisphenol A-Glycidyl Methacrylate , Dental Bonding , Graphite , Dental Cements , Resin Cements/chemistry , Materials Testing , Composite Resins/chemistry , Adhesives/chemistry
5.
Eur J Orthod ; 45(6): 645-661, 2023 11 30.
Article in English | MEDLINE | ID: mdl-37824794

ABSTRACT

OBJECTIVES: To systematically assess the scientific literature for the prevalence of failure rate of fixed orthodontic bonded retainer (FOBR). METHOD: Randomized clinical trials (RCTs) and prospective non-RCTs involving participants who had FOBR fitted were included. The Cochrane Central Register of Controlled Trials, Web of science, MEDLINE, and EMBASE via OVID were searched from inception to January 2023. Risk of bias was assessed using the Cochrane RoB 2 and Newcastle-Ottawa tools. The main outcome was the failure rate of FOBRs. The secondary outcome was to identify factors that can influence the failure of FOBR. Meta-analyses and sensitivity analyses were undertaken using Revman, version5.4. A random-effects model was used. Quality assessment using Grading of Recommendations Assessment, Development, and Evaluation. RESULTS: Thirty-four studies (25 RCTs and 9 prospective clinical studies) (3484 participants) were included in this review. The overall failure rate of bonded retainers, after excluding high-risk studies, was 35.22% (95% confidence interval [CI] 27.46-42.98). The failure rate is increased with the duration of follow up; with short-term follow-up rate 24.18% (95% CI 20.16-28.21), medium-term follow up 40.09% (95% CI 30.92-49.26), and long-term follow up 53.85% (95% CI 40.31-67.39). There is a low level of evidence to suggest there is no statistically significant difference in the failure rate of fixed retainers using direct versus indirect bonding methods, using liquid resin versus without liquid resin, and fibre-reinforced composite retainers compared to multi-stranded stainless steel retainers. DISCUSSION: There is low-quality evidence to suggest that the failure rate of FOBR is relatively high. There is a need for high-quality, well-reported clinical studies to assess factors that can influence the failure rate of FOBR. REGISTRATION: CRD42021190910.


Subject(s)
Orthodontic Appliances, Fixed , Orthodontic Retainers , Humans , Prevalence , Prospective Studies , Stainless Steel
6.
Plant Physiol ; 193(4): 2768-2787, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37648267

ABSTRACT

The efficient infection of plants by the bacteria Xanthomonas campestris pv. campestris (Xcc) depends on its type III effectors (T3Es). Although the functions of AvrE family T3Es have been reported in some bacteria, the member XopAM in Xcc has not been studied. As XopAM has low sequence similarity to reported AvrE-T3Es and different reports have shown that these T3Es have different targets in hosts, we investigated the functions of XopAM in the Xcc-plant interaction. Deletion of xopAM from Xcc reduced its virulence in cruciferous crops but increased virulence in Arabidopsis (Arabidopsis thaliana) Col-0, indicating that XopAM may perform opposite functions depending on the host species. We further found that XopAM is a lipase that may target the cytomembrane and that this activity might be enhanced by its membrane-targeted protein XOPAM-ACTIVATED RESISTANCE 1 (AMAR1) in Arabidopsis Col-0. The binding of XopAM to AMAR1 induced an intense hypersensitive response that restricted Xcc proliferation. Our results showed that the roles of XopAM in Xcc infection are not the same as those of other AvrE-T3Es, indicating that the functions of this type of T3E have differentiated during long-term bacterium‒host interactions.


Subject(s)
Arabidopsis , Xanthomonas campestris , Arabidopsis/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Membrane Proteins/metabolism , Virulence , Virulence Factors/metabolism , Plant Diseases/microbiology
7.
Sensors (Basel) ; 23(11)2023 May 29.
Article in English | MEDLINE | ID: mdl-37299903

ABSTRACT

The core of eLoran ground-based timing navigation systems is the accurate measurement of groundwave propagation delay. However, meteorological changes will disturb the conductive characteristic factors along the groundwave propagation path, especially for a complex terrestrial propagation environment, and may even lead to microsecond-level propagation delay fluctuation, seriously affecting the timing accuracy of the system. Aiming at this problem, this paper proposes a propagation delay prediction model based on a Back-Propagation neural network (BPNN) for a complex meteorological environment, which realizes the function of directly mapping propagation delay fluctuation through meteorological factors. First, the theoretical influence of meteorological factors on each component of propagation delay is analyzed based on calculation parameters. Then, through the correlation analysis of the measured data, the complex relationship between the seven main meteorological factors and the propagation delay, as well as their regional differences, are demonstrated. Finally, a BPNN prediction model considering regional changes of multiple meteorological factors is proposed, and the validity of the model is verified by long-term collected data. Experimental results show that the proposed model can effectively predict the propagation delay fluctuation in the next few days, and its overall performance is significantly improved compared with that of the existing linear model and simple neural network model.


Subject(s)
Meteorological Concepts , Neural Networks, Computer , Linear Models , Data Collection
8.
Sci Educ (Dordr) ; : 1-32, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37359259

ABSTRACT

Science educators report that students struggle with understanding, using, and evaluating the evidence underpinning scientific knowledge. However, there are not many studies focused on helping instructors address those difficulties. Here, we report on a laboratory instructor's scaffolding of students' evidentiary reasoning with and about evidence for evolutionary trees with guidance from the Conceptual Analysis of Disciplinary Evidence (CADE) framework, which links biological knowledge with epistemic considerations. To consider both domain-general and discipline-specific aspects of evidence, CADE was implemented to inform scaffolds in two ways: (1) generic evidence scaffolds (GES) reminded students of general epistemic considerations; (2) disciplinary evidence scaffolds (DES) explicitly reminded students of the disciplinary knowledge of relevance for considering biological evidence. An instructor's lab discussions were compared before and after they had a workshop with CADE. CADE helped the lab instructor facilitate students' evidentiary reasoning about evolutionary trees. In comparison to baseline, both GES and DES discussions covered more aspects and relationships among types of evidence for evolutionary tree-thinking and the instructor prompted more kinds of general epistemic considerations and biological knowledge. DES discussions emphasized the importance of disciplinary knowledge for research design. The CADE framework guided planning and implementation of intentional scaffolding aimed at guiding evidentiary reasoning. Supplementary Information: The online version contains supplementary material available at 10.1007/s11191-023-00435-6.

9.
ACS Appl Mater Interfaces ; 15(19): 23276-23285, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37148281

ABSTRACT

High-entropy alloys (HEAs), as new heterogeneous catalytic materials, possess remarkable catalytic performance in numerous reactions. However, rational and controllable synthesis of these complex structures remains a challenge. In this work, bulk and carbon nanotube (CNT)-supported ultrasmall PtFeCoNiCu HEA nanoparticles with an average particle size of 1.58 nm are prepared by lithium naphthalenide-driven reduction under mild conditions. The supported PtFeCoNiCu/CNT catalyst exhibits high catalytic activity in the aqueous-phase hydrogenation of maleic anhydride to succinic acid with a selectivity of 98% at full conversion of maleic acid (the hydrolysis product of maleic anhydride), a low apparent activation energy (Ea = 49 kJ mol-1), and excellent stability. Moreover, a much higher mass-specific activity of Pt in the catalyst is displayed over PtFeCoNiCu/CNT (1515.4 mmolmaleic acid gPt-1 h-1) than that of 5 wt % Pt/CNT (388.0 mmolmaleic acid gPt-1 h-1). This work provides a strong support for HEAs as advanced heterogeneous catalysts and will be of great significance for promoting the research and application of HEAs in the field of selective hydrogenation.

10.
Elife ; 122023 03 30.
Article in English | MEDLINE | ID: mdl-36995744

ABSTRACT

Many pathogens rely on their insect vectors for transmission. Such pathogens are under selection to improve vector competence for their transmission by employing various tissue or cellular responses of vectors. However, whether pathogens can actively cause hypoxia in vectors and exploit hypoxia responses to promote their vector competence is still unknown. Fast dispersal of pinewood nematode (PWN), the causal agent for the destructive pine wilt disease and subsequent infection of pine trees, is characterized by the high vector competence of pine sawyer beetles (Monochamus spp.), and a single beetle can harbor over 200,000 PWNs in its tracheal system. Here, we demonstrate that PWN loading activates hypoxia in tracheal system of the vector beetles. Both PWN loading and hypoxia enhanced tracheal elasticity and thickened the apical extracellular matrix (aECM) of the tracheal tubes while a notable upregulated expression of a resilin-like mucin protein Muc91C was observed at the aECM layer of PWN-loaded and hypoxic tracheal tubes. RNAi knockdown of Muc91C reduced tracheal elasticity and aECM thickness under hypoxia conditions and thus decreasing PWN loading. Our study suggests a crucial role of hypoxia-induced developmental responses in shaping vector tolerance to the pathogen and provides clues for potential molecular targets to control pathogen dissemination.


Various parasites, bacteria and other disease-causing pathogens are transmitted by insects. A tiny worm called the pine wood nematode, for example, is spread by pine sawyer beetles which can carry up to 280,000 worms in their trachea, the network of tubes they use to breathe. This has resulted in millions of hectares of pine forests in Asia and Europe becoming infected with the deadly disease caused by the nematodes. Pine wood nematodes, as well as other pathogens, can exploit the biological processes of the insects carrying them to make the insects transmit them more effectively. Precisely how nematodes and other disease-causing agents do this is unclear. One possibility is that they reduce the amount of oxygen being supplied to the trachea ­ a phenomenon known as hypoxia ­ which occurs naturally at specific stages in the life of an insect, and during infections. To test this theory, Tang, Zhou, Koski et al. used genetics and imaging approaches to study how pine wood nematodes affect the trachea of pine sawyer beetles. The experiments found that when the nematodes infected the beetles, their trachea did indeed develop hypoxia. This, in turn, made the beetles' airways more elastic and made the layer of structure lining the trachea, known as the apical extracellular matrix, thicker. These changes increased the amount of pinewood nematodes the trachea could hold, allowing the beetle to spread more worms from tree to tree. Further experiments revealed that hypoxia in the trachea increased the levels of a protein called Muc91C in the apical extracellular matrix. When the levels of Muc91C were artificially decreased in the beetles, this made their airways less elastic and the apical extracellular matrix thinner. This work suggests that pine wood nematodes exploit the beetles' normal responses to loss of oxygen supply to make the beetles more effective at transmitting the nematodes between pine trees. Other pathogens carried by insects may also use this strategy to help increase their transmission. Further studies on the Muc91C protein may provide clues for potential drug targets to control pine wood nematodes and protect pine trees from disease.


Subject(s)
Coleoptera , Nematoda , Pinus , Animals , Coleoptera/physiology , Pinus/physiology , Insect Vectors
11.
Phys Chem Chem Phys ; 25(6): 4803-4809, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36692367

ABSTRACT

The exploration of efficient single-atom catalysts provides a prospective pattern for the sustainable development of electrocatalytic nitrogen fixation. We systematically researched the nitrogen reduction properties of catalysts with a single transition metal (TM) atom sandwiched between BN-doped graphdiyne and graphdiyne (labeled BN-TM-G) by first-principles calculations. The TM atom in the novel sandwich structure provides electrons to the adjacent B atom, which acts as the active site, thus driving the fixation and reduction of N2. In the BN-TM-G system, the NRR catalytic activity is bound up with the positive charge polarization level of the TM atom. Among them, BN-Sc-G, BN-Ti-G, BN-V-G, and BN-Cr-G systems showed higher catalytic ability, and the competitive HER was inhibited. In particular, the lowest limiting potential of BN-Cr-G is -0.63 V is promising for the NRR catalyst.

12.
Am J Orthod Dentofacial Orthop ; 162(5): 601-615.e2, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36031511

ABSTRACT

INTRODUCTION: Orthodontic fixed retainers are preferred as they depend less on patient compliance. Recently, researchers tried to use fiber-reinforced composite (FRC) to replace the multistranded stainless-steel wire (MSW) of the fixed retainers to enhance the mechanical properties and esthetics. This systematic review aimed to analyze the effectiveness of the FRC retainers. METHODS: We searched the electronic databases (May 1, 2021), including Medline, the Cochrane Library, EMBASE, PubMed, Web of Science, and CINAHL. We applied no language or date restrictions in the searches of the databases. Only randomized controlled trials (RCTs) and prospective clinical controlled trials were included. The revised Cochrane risk of bias tool for randomized trials and risk of bias in nonrandomized studies of interventions were used to evaluate the risk of bias in RCTs and non-RCTs, respectively. The outcomes were pooled using Review Manager 5.4. The primary outcome of this review was teeth relapse, and the secondary outcomes were bonded retainer failure rate, adverse effect on oral health, and patient's satisfaction. RESULTS: Eleven out of 99 studies, which included 873 participants, were used in this review, with the follow-up ranging from 6 months to 6 years. Ten studies compared the FRC retainers with MSW retainers, and 1 study compared FRC retainers with a different fiber material. Ten studies were RCT, and 1 was non-RCT. There was 0.39 less relapse with the FRC retainers than with MSW retainers (mean difference, -0.39; 95% confidence interval [CI], -0.41 to -0.37; P <0.00001). There was no statistically significant difference in the failure rate between the FRC and MSW with the whole retainer as an outcome unit risk ratio of 1.72 (95% CI, 0.57-5.14; P = 0.33) or with the teeth an as outcome unit risk ratio of 0.85 (95% CI, 0.47-1.52; P = 0.58). There was insufficient evidence to conduct the meta-analysis of the adverse effect on oral health and patient satisfaction. CONCLUSIONS: Low-quality evidence is available to suggest that the effectiveness of the FRC is comparable to the MSW with no significant difference in the failure rate. However, we have very low certainty on these results. It is worth conducting future robust clinical studies to assess the effectiveness of FRC retainers with long follow-up.

13.
Foods ; 11(7)2022 Mar 31.
Article in English | MEDLINE | ID: mdl-35407106

ABSTRACT

Chaenomeles speciosa (Sweet) Nakai (C. speciosa) is not only a Chinese herbal medicine but also a functional food widely planted in China. Its fruits are used to treat many diseases or can be processed into food products. This study aims to find key metabolic components, distinguish the differences between geographical regions and find more medicinal and edible values of C. speciosa fruits. We used ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and widely targeted metabolomics analysis to reveal key and differential metabolites. We identified 974 metabolites and screened 548 differential metabolites from 8 regions. We selected significantly high-content differential metabolites to visualize a regional biomarker map. Comparative analysis showed Yunnan had the highest content of total flavonoids, the highest amounts of compounds related to disease resistance and drug targets and the most significant difference from the other regions according to the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database, a unique platform for studying the systematic pharmacology of Chinese herbal medicine and capturing the relationship between drugs, targets and diseases. We used oral bioavailability (OB) ≥ 30% and drug likeness (DL) ≥ 0.18 as the selection criteria and found 101 key active metabolites, which suggests that C. speciosa fruits were rich in healthy metabolites. These results provide valuable information for the development of C. speciosa.

14.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-923504

ABSTRACT

@#With the aging of the population and the increase in the number of edentulous patients, implant-supported fixed restorations have become more prevalent in clinical treatment. It is necessary to assess the patient's remaining bone and occlusal situation correctly; the upper jaw usually needs 6 to 8 implants, whereas the lower jaw needs 4 to 6 implants. Patients with severe alveolar bone atrophy can adopt the "all-on-4/6" treatment plan, short implants, and zygomatic and pterygomaxillary implants to avoid complex bone grafting and remain cautious when the surgical procedures require more surgical experience. According to the repair methods, the superstructure can be divided into one-piece repair and segmental repair. One-piece repair has a lower implant number, flexible location, and reasonable stress distribution but a high maintenance cost. Sectional repair easily achieves passive placement, convenient cleaning, and maintenance in the late stages, but implants need quantity and high requirements for alveolar bone. However, the requirements for alveolar bone and implant number are high. Mutually protected occlusion with minimal or no cantilever on provisional prosthesis is recommended.

15.
Front Oncol ; 11: 783860, 2021.
Article in English | MEDLINE | ID: mdl-34950590

ABSTRACT

Golgi phosphoprotein 73 (GP73, also termed as GOLM1 or GOLPH2) is a glycosylated protein residing on cis-Golgi cisternae and highly expressed in various types of cancer tissues. Since GP73 is a secretory protein and detectable in serum derived from cancer patients, it has been regarded as a novel serum biomarker for the diagnosis of different cancers, especially hepatocellular carcinoma (HCC). However, the functional roles of GP73 in cancer development are still poorly understood. In recent years, it has been discovered that GP73 acts as a multifunctional protein-facilitating cancer progression, and strikingly, it has been identified as a leading factor promoting epithelial-mesenchymal transition (EMT) of cancer cells and causing cancer metastasis. In this review, we have overviewed the latest findings of the functional roles of GP73 in elevating cancer progression, especially in facilitating EMT and cancer metastasis through modulating expression, transactivation, and trafficking of EMT-related proteins. In addition, unsolved research fields of GP73 have been lightened, which might be helpful to elucidate the regulatory mechanisms of GP73 on EMT and provide potential approaches in therapeutics against cancer metastasis.

16.
Chemistry ; 27(63): 15562, 2021 Nov 11.
Article in English | MEDLINE | ID: mdl-34730261

ABSTRACT

Invited for the cover of this issue are Ken Sakata, Yoshiaki Nishibayashi, and co-workers at The University of Tokyo and Toho University. The image depicts the propargylic substitution reaction of a propargylic alcohol with an N-monosubstituted hydrazone, where the nucleophilicity of the hydrazone is controlled by the choice of catalytic system. Read the full text of the article at 10.1002/chem.202103287.


Subject(s)
Ruthenium , Catalysis , Copper , Humans , Hydrazones
17.
Chemistry ; 27(63): 15650-15659, 2021 Nov 11.
Article in English | MEDLINE | ID: mdl-34606139

ABSTRACT

Ruthenium- and copper-catalyzed propargylic substitution reactions of propargylic alcohol derivatives with N-monosubstituted hydrazones as ambident nucleophiles are achieved in which N-monosubstituted hydrazones exhibit impressive different reactivities depending on different catalytic systems, behaving as carbon-centered nucleophiles to give the corresponding propargylic alkylated products in ruthenium catalysis, or as nitrogen-centered nucleophiles to afford the corresponding propargylic aminated products in copper catalysis. DFT calculations were carried out to investigate the detailed reaction pathways of these two systems. Further transformation of propargylic substituted products affords the corresponding multisubstituted pyrazoles as cyclization products in good to high yields.

18.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3592-3598, 2021 Jul.
Article in Chinese | MEDLINE | ID: mdl-34402282

ABSTRACT

Thirteen compounds were isolated and purified from the leaves of Cinnamomum camphora by the macroporous resin,silica gel,and Sephadex LH-20 column chromatographies. Those compounds were further identified by IR,UV,MS,and NMR techniques:( 2 S)-1-( 3″,4″-methylenedioxy phenyl)-3-( 2',6'-dimethoxy-4'-hydroxyphenyl)-propan-2-ol( 1),( 2 R,3 R)-5,7-dimethoxy-3',4'-methylenedioxy flavanol( 2),9-hydroxysesamin( 3),sesamin( 4),piperitol( 5),kobusin( 6),(-)-aptosimon( 7),acuminatolide( 8),1ß,11-dihydroxy-5-eudesmene( 9),lasiodiplodin( 10),vanillin( 11),p-hydroxybenzaldehyde( 12),and p-hydroxybenzoic acid ethyl ester( 13). Compound 1 was a novel compound,and compounds 2,6,7,9 and 10 were isolated from Cinnamomum plants for the first time. Compounds 4,7 and 10 were found to possess good inhibitory effect on IL-6 production in LPS-induced BV2 cells at a concentration of 20 µmol·L-1 in the in vitro bioassay,with inhibition rates of 51. 26% ± 4. 13%,67. 82% ± 3. 77% and85. 81%±1. 19%,respectively.


Subject(s)
Cinnamomum camphora , Cinnamomum , Anti-Inflammatory Agents/pharmacology , Plant Leaves
19.
Food Chem ; 356: 129643, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-33812190

ABSTRACT

A rapid screening method of 70 colorants for regulatory control in dyeable foods was established using ultra-high-performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-Q/Orbitrap MS) with customized accurate-mass database and mass spectral library. A rapid, high-throughput, and simple sample pretreatment condition with low reagent consumption and high recovery was developed on the basis of ultrasound-assisted extraction and dispersion solid-phase extraction. Rapid screening was conducted by comparing the experimentally measured exact mass of the parent and fragment ions, the isotope pattern, and the retention time with the accurate-mass database and by matching the acquired MS/MS spectra against the mass spectral library. The performance of the method was evaluated in terms of linearity, limits of detection, limits of quantitation, recovery, repeatability, reproducibility, and matrix effect. The proposed method was applied for simultaneous analysis of 70 colorants in seven kinds of dyeable foods, and it exhibited great potential for broad, sensitive, and reliable.


Subject(s)
Food Coloring Agents/chemistry , Chromatography, High Pressure Liquid , Databases, Factual , Food , Limit of Detection , Reproducibility of Results , Solid Phase Extraction , Tandem Mass Spectrometry , Time Factors
20.
Angew Chem Int Ed Engl ; 60(20): 11231-11236, 2021 May 10.
Article in English | MEDLINE | ID: mdl-33826795

ABSTRACT

The development of transition metal-catalyzed enantioselective propargylic substitution reactions has gained much progress in recent years, however, no successful example with phosphorus-centered nucleophiles has yet been reported until now. Herein, we report the first successful example of ruthenium-catalyzed enantioselective propargylic substitution reactions of propargylic alcohols with diarylphosphine oxides as phosphorus-centered nucleophiles. This synthetic approach provides a new method to prepare chiral phosphorus-containing organic compounds.

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