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1.
Dig Dis Sci ; 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34822025

RESUMO

BACKGROUND: Cancer progression can be regulated by noncoding circular RNAs. A recent study has indicated that circ_0044556 facilitated the progression of colorectal cancer. AIM: This research was performed to explore the regulatory mechanism of circ_0044556 in CRC. METHODS: Circ_0044556, miR-665 and Diaphanous Homolog 1 levels were detected by the quantitative real-time polymerase chain reaction. Cell proliferation analysis was performed by cell counting kit-8 assay and Edu assay. Cell cycle progression was assessed using flow cytometry. The protein examination was conducted using western blot. Transwell assay was used to analyze cell migration and invasion. Dual-luciferase reporter assay was performed to validate the interaction between targets. In vivo research was implemented by xenograft tumor assay. RESULTS: Circ_0044556 was upregulated in colorectal cancer samples and cells. Silencing circ_0044556 inhibited cell proliferation, cell cycle progression, migration, invasion, and epithelial-mesenchymal transition in CRC cells. Circ_0044556 could directly target miR-665 and the function of circ_0044556 was associated with the regulation of miR-665. In addition, Diaphanous Homolog 1 was a target gene for miR-665 and the anti-tumor role of miR-665 in colorectal cancer was dependent on the downregulation of Diaphanous Homolog 1. Diaphanous Homolog 1 level was regulated by circ_0044556 via sponging miR-665 in CRC cells. In vivo assay suggested that circ_0044556 promoted CRC tumor growth by regulating the miR-665 and Diaphanous Homolog 1 levels. CONCLUSION: Our findings manifested that circ_0044556 functioned as an oncogenic circRNA in colorectal cancer by mediating the miR-665/Diaphanous Homolog 1 axis, elucidating the molecular mechanism of circ_0044556 in CRC progression.

2.
Am J Chin Med ; 49(7): 1577-1622, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34559620

RESUMO

Schisandra sphenanthera Rehd. et Wils (S. sphenanthera) is a single species of Schisandra genus, Magnoliaceae family, and it is a famous medicinal herb mostly growing in southern China, China Taiwan and Vietnam. S. sphenanthera is usually used for the treatments of hepatitis, Alzheimer's disease, renal transplantation, osteoporosis, and insomnia. In present studies, approximately 310 natural constituents have been isolated from S. sphenanthera, including lignans, triterpenes, volatile oils, and polysaccharides, which were mainly obtained from the fruits and stems of S. sphenanthera. Pharmocological studies have shown that the extracts and monomeric compounds of S. sphenanthera possessed wide-range bioactivities, such as antitumor, anti-oxidant, anti-inflammatory, osteoblastic, immune regulation, neuroprotective, kidney protection, hepatoprotective, and antiviral activities. However, resource availability, quality control measures, in-depth in vivo pharmacological study, and clinical application are still insufficient and deserve further studies. This review systematically summarized literatures on the botany, phytochemistry, pharmacology, development utilization, and clinical application of S. sphenanthera, in hopes of provide a useful reference for researchers for further studies of this plant.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34306148

RESUMO

Background: Coronavirus disease 2019 (COVID-19) causes psychological distress and can have a negative impact on the general mental health and rehabilitation in affected patients under currently implemented isolation guidelines. Auricular point pressure (APP) as well-established technique in traditional Chinese medicine may help to relieve sleep disturbance and anxiety in COVID-19 patients. Methods: During the early phase of the epidemic/pandemic, patients were enrolled in this study (02/2020 until 03/2020 n = 84). They were strictly isolated on specific wards at the Hubei Provincial Hospital of Integrated Chinese and Western Medicine in Hubei. The retrospective cohort study design included two groups. Group A patients were treated with an auricular point pressure (APP) in addition to standard intensive care medicine while Group B participants (No-APP) received routine nursing measures alone. Treatment outcome was measured using the St. Mary's Hospital Sleep Questionnaire (SMH) Score and the 7-Item Generalized Anxiety Disorder Scale (GAD-7). Both scores were measured in each patient at baseline and on the discharge day. Results: The SMH score and sleep status changed in APP patients at the end of the treatment period when compared with No-APP patients (P < 0.01). APP-treated patients demonstrated lower GAD-7 scores than No-APP controls (P < 0.01). Further, no significant differences in safety or adverse events between the APP and No-APP groups were observed. Conclusion: The results from our snapshot study during the early phase of the SARS-CoV-2 epidemic/pandemic suggest that auricular point pressure could be a simple and effective tool to relieve insomnia and situational anxiety in hospitalized patients suffering from COVID-19 and kept under disconcerting conditions of isolation.

4.
Front Immunol ; 12: 656366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149695

RESUMO

Amphioxus (e.g., Branchiostoma belcheri, Bb) has recently emerged as a new model for studying the origin and evolution of vertebrate immunity. Mammalian lymphocyte-specific tyrosine kinase (Lck) plays crucial roles in T cell activation, differentiation and homeostasis, and is reported to phosphorylate both the ITIM and ITSM of PD-1 to induce the recruitment of phosphatases and thus the inhibitory function of PD-1. Here, we identified and cloned the amphioxus homolog of human Lck. By generating and using an antibody against BbLck, we found that BbLck is expressed in the amphioxus gut and gill. Through overexpression of BbLck in Jurkat T cells, we found that upon TCR stimulation, BbLck was subjected to tyrosine phosphorylation and could partially rescue Lck-dependent tyrosine phosphorylation in Lck-knockdown T cells. Mass spectrometric analysis of BbLck immunoprecipitates from immunostimulants-treated amphioxus, revealed a BbLck-associated membrane-bound receptor LRR (BbLcLRR). By overexpressing BbLcLRR in Jurkat T cells, we demonstrated that BbLcLRR was tyrosine phosphorylated upon TCR stimulation, which was inhibited by Lck knockdown and was rescued by overexpression of BbLck. By mutating single tyrosine to phenylalanine (Y-F), we identified three tyrosine residues (Y539, Y655, and Y690) (3Y) of BbLcLRR as the major Lck phosphorylation sites. Reporter gene assays showed that overexpression of BbLcLRR but not the BbLcLRR-3YF mutant inhibited TCR-induced NF-κB activation. In Lck-knockdown T cells, the decline of TCR-induced IL-2 production was reversed by overexpression of BbLck, and this reversion was inhibited by co-expression of BbLcLRR but not the BbLcLRR-3YF mutant. Sequence analysis showed that the three tyrosine-containing sequences were conserved with the tyrosine-based inhibition motifs (ITIMs) or ITIM-like motifs. And TCR stimulation induced the association of BbLcLRR with tyrosine phosphatases SHIP1 and to a lesser extent with SHP1/2. Moreover, overexpression of wild-type BbLcLRR but not its 3YF mutant inhibited TCR-induced tyrosine phosphorylation of multiple signaling proteins probably via recruiting SHIP1. Thus, we identified a novel immunoreceptor BbLcLRR, which is phosphorylated by Lck and then exerts a phosphorylation-dependent inhibitory role in TCR-mediated T-cell activation, implying a mechanism for the maintenance of self-tolerance and homeostasis of amphioxus immune system and the evolutionary conservatism of Lck-regulated inhibitory receptor pathway.


Assuntos
Receptores Coestimuladores e Inibidores de Linfócitos T/metabolismo , Anfioxos/metabolismo , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Animais , Biomarcadores , Clonagem Molecular , Receptores Coestimuladores e Inibidores de Linfócitos T/genética , Bases de Dados Genéticas , Ensaio de Imunoadsorção Enzimática , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunofenotipagem , Interleucina-2/biossíntese , Células Jurkat , Anfioxos/genética , Ativação Linfocitária , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/genética , Fosforilação , Coelhos , Receptores de Antígenos de Linfócitos T/metabolismo , Análise de Sequência de DNA , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
5.
Front Immunol ; 12: 691559, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122457

RESUMO

Interleukin-17E (IL-25) is a member of the IL-17 cytokine family that includes IL-17A to IL-17F. IL-17 family cytokines play a key role in host defense responses and inflammatory diseases. Compared with other IL-17 cytokine family members, IL-25 has relatively low sequence similarity to IL-17A and exhibits a distinct function from other IL-17 cytokines. IL-25 binds to its receptor composed of IL-17 receptor A (IL-17RA) and IL-17 receptor B (IL-17RB) for signal transduction. IL-25 has been implicated as a type 2 cytokine and can induce the production of IL-4, IL-5 and IL-13, which in turn inhibits the differentiation of T helper (Th) 17. In addition to its anti-inflammatory properties, IL-25 also exhibits a pro-inflammatory effect in the pathogenesis of Th17-dominated diseases. Here, we review recent advances in the roles of IL-25 in the pathogenesis of inflammation and autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Inflamação/imunologia , Interleucina-17/imunologia , Animais , Humanos , Transdução de Sinais
6.
Food Chem ; 358: 129856, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933975

RESUMO

W/O/W emulsions were easily prepared by oleogelation of the oil phase using rice bran wax (RBX) and their microstructure, stability, rheology and protection of proanthocyanidins and ß-carotene were investigated. Formation of the W/O/W emulsion was confirmed using confocal laser scanning microscopy and staining of the inner aqueous phase by tartrazine. The average particle size and viscosity of the emulsion increased as the RBX concentration increased. Moreover, RBX increased the stability of the emulsion and the emulsion was the most stable when the RBX concentration was 8.0% or 10.0%. On the other hand, the W/O/W emulsions were used to simultaneously encapsulate proanthocyanidins and ß-carotene. Specifically, proanthocyanidins and ß-carotene in RBX-containing emulsions were more stable and had higher bioaccessibility than in the emulsion without RBX. Besides, both their chemical stability and bioaccessibility reached the maximum value when the RBX concentration was 8.0% or 10.0%. In summary, the optimal RBX concentration was 8.0%.


Assuntos
Emulsões/química , Proantocianidinas/química , Óleo de Farelo de Arroz/química , beta Caroteno/química , Óleo de Milho/química , Armazenamento de Alimentos , Tamanho da Partícula , Proantocianidinas/farmacocinética , Reologia , Viscosidade , Água/química , beta Caroteno/farmacocinética
7.
Clin Transl Immunology ; 10(4): e1277, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968407

RESUMO

Objectives: This study aims to determine a role of interleukin-17A (IL-17) in salivary gland (SG) dysfunction and therapeutic effects of targeting IL-17 in SG for treating autoimmune sialadenitis in primary Sjögren's syndrome (pSS). Methods: Salivary IL-17 levels and IL-17-secreting cells in labial glands of pSS patients were examined. Kinetic changes of IL-17-producing cells in SG from mice with experimental Sjögren's syndrome (ESS) were analysed. To determine a role of IL-17 in salivary secretion, IL-17-deficient mice and constructed chimeric mice with IL-17 receptor C (IL-17RC) deficiency in non-hematopoietic and hematopoietic cells were examined for saliva flow rates during ESS development. Both human and murine primary SG epithelial cells were treated with IL-17 for measuring cholinergic activation-induced calcium movement. Moreover, SG functions were assessed in ESS mice with salivary retrograde cannulation of IL-17 neutralisation antibodies. Results: Increased salivary IL-17 levels were negatively correlated with saliva flow rates in pSS patients. Both IL-17-deficient mice and chimeric mice with non-hematopoietic cell-restricted IL-17RC deficiency exhibited no obvious salivary reduction while chimeric mice with hematopoietic cell-restricted IL-17RC deficiency showed significantly decreased saliva secretion during ESS development. In SG epithelial cells, IL-17 inhibited acetylcholine-induced calcium movement and downregulated the expression of transient receptor potential canonical 1 via promoting Nfkbiz mRNA stabilisation. Moreover, local IL-17 neutralisation in SG markedly attenuated hyposalivation and ameliorated tissue inflammation in ESS mice. Conclusion: These findings identify a novel function of IL-17 in driving salivary dysfunction during pSS development and may provide a new therapeutic strategy for targeting SG dysfunction in pSS patients.

8.
Tree Physiol ; 41(2): 280-301, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33104211

RESUMO

Citrus sinensis (L.) Osbeck seedlings were fertigated with nutrient solution containing 2 [magnesium (Mg)-sufficiency] or 0 mM (Mg-deficiency) Mg(NO3)2 for 16 weeks. Thereafter, RNA-Seq was used to investigate Mg-deficiency-responsive genes in the veins of upper and lower leaves in order to understand the molecular mechanisms for Mg-deficiency-induced vein lignification, enlargement and cracking, which appeared only in the lower leaves. In this study, 3065 upregulated and 1220 downregulated, and 1390 upregulated and 375 downregulated genes were identified in Mg-deficiency veins of lower leaves (MDVLL) vs Mg-sufficiency veins of lower leaves (MSVLL) and Mg-deficiency veins of upper leaves (MDVUL) vs Mg-sufficiency veins of upper leaves (MSVUL), respectively. There were 1473 common differentially expressed genes (DEGs) between MDVLL vs MSVLL and MDVUL vs MSVUL, 1463 of which displayed the same expression trend. Magnesium-deficiency-induced lignification, enlargement and cracking in veins of lower leaves might be related to the following factors: (i) numerous transciption factors and genes involved in lignin biosynthesis pathways, regulation of cell cycle and cell wall metabolism were upregulated; and (ii) reactive oxygen species, phytohormone and cell wall integrity signalings were activated. Conjoint analysis of proteome and transcriptome indicated that there were 287 and 56 common elements between DEGs and differentially abundant proteins (DAPs) identified in MDVLL vs MSVLL and MDVUL vs MSVUL, respectively, and that among these common elements, the abundances of 198 and 55 DAPs matched well with the transcript levels of the corresponding DEGs in MDVLL vs MSVLL and MDVUL vs MSVUL, respectively, indicating the existence of concordances between protein and transcript levels.


Assuntos
Citrus sinensis , Citrus , Citrus/metabolismo , Citrus sinensis/genética , Citrus sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Magnésio/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , RNA-Seq , Transcriptoma
9.
Cell Mol Immunol ; 18(7): 1739-1750, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32917979

RESUMO

Recent studies have demonstrated a central role for plasma cells in the development of autoimmune diseases, such as systemic lupus erythematosus (SLE). Currently, both the phenotypic features and functional regulation of autoreactive plasma cells during SLE pathogenesis remain largely unclear. In this study, we first found that a major subset of IL-17 receptor-expressing plasma cells potently produced anti-dsDNA IgG upon IL-17A (IL-17) stimulation in SLE patients and lupus mice. Using a humanized lupus mouse model, we showed that the transfer of Th17 cell-depleted PBMCs from lupus patients resulted in a significantly reduced plasma cell response and attenuated renal damage in recipient mice compared to the transfer of total SLE PBMCs. Moreover, long-term BrdU incorporation in lupus mice detected highly enriched long-lived BrdU+ subsets among IL-17 receptor-expressing plasma cells. Lupus mice deficient in IL-17 or IL-17 receptor C (IL-17RC) exhibited a diminished plasma cell response and reduced autoantibody production with attenuated renal damage, while the adoptive transfer of Th17 cells triggered the plasma cell response and renal damage in IL-17-deficient lupus mice. In reconstituted chimeric mice, IL-17RC deficiency resulted in severely impaired plasma cell generation but showed no obvious effect on germinal center B cells. Further mechanistic studies revealed that IL-17 significantly promoted plasma cell survival via p38-mediated Bcl-xL transcript stabilization. Together, our findings identified a novel function of IL-17 in enhancing plasma cell survival for autoantibody production in lupus pathogenesis, which may provide new therapeutic strategies for the treatment of SLE.

10.
Nat Prod Res ; 35(1): 108-115, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31137985

RESUMO

Three new steroidal saponins (1-3), together with four known compounds (4-7), were isolated from the roots and rhizomes of Rohdea chinensis Baker, and their structures were determined as (24S, 25 R)-1ß-hydroxy-3ß-[(ß-D-glucopyranoside)oxy]-spirost-5-en-24-yl-ß-D-glucopyranoside (1) and (24S)-spirost-25(27)-en-1ß, 3ß, 4ß, 5ß, 6ß, 24ß-hexahydroxy-24-O-ß-D-glucopyranoside (2), (22S, 25S)-1ß, 3ß, 4ß, 5ß, 26, 27-hexanol-furospirost-5, 26-O-ß-D-glucopyranoside (3), together with four known compounds 3-epi-diosgenin-3-ß-D-glucopyranosid (4), 3-epiruscogenin (5), 25(R)-1ß-hydroxy-spirost-5-en-3α-yl-O-ß-D-glucopyranoside (6) and tupichinin A (7), on the basis of physico-chemical properties and spectral analysis. In this study, compounds 1-3 and 5-7 were evaluated for their cytotoxic activity against SW620, A549 and HepG2 tumor cell lines. Among them, compound 7 showed moderate cytotoxicity against two human cancer cell lines A549 and HepG 2 with IC50 values of 25.3 ± 2.6 and 26.1 ± 2.5 µM, respectively.


Assuntos
Asparagaceae/química , Saponinas/química , Saponinas/farmacologia , Células A549 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rizoma/química , Esteroides/química
11.
Bioorg Chem ; 106: 104512, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33293056

RESUMO

This study aimed to obtain tyrosinase inhibitors for treating hyperpigmentation. A series of cinnamyl ester analogues were designed and synthesized with cinnamic acid (CA) and peaonol compounds. The safety, melanin content and inhibitory effects of all target compounds were evaluated. In the enzymatic activity test, the inhibitory rate of compounds 8, 13 and 14 had stronger inhibitory activity with the IC50 values of 20.7 µM, 13.98 µM and 15.16 µM, respectively than the positive drug kojic acid (IC50 with 30.83 µM). The cytotoxicity evaluation showed that compounds 13 and 14 have higher safety than the other compounds to the proliferation of B16F10 cells. The result of the melanocyte test supported that compound13 has stronger cellular tyrosinase inhibitory activity than kojic acid and arbutin at 100 µM and 200 µM. The enzyme kinetics mechanism revealed that compound 13 was a non-competitive inhibitor while compounds 8 and 14 were mixed inhibitors. For the experiments of melanin content and tyrosinase activity in the B16F10 melanona cells, the inhibition rates of compounds 8, 14 and 13 were with 19.62%, 20.59% and 23.83%, respectively. In addition, compound 13 revealed the highest inhibitory activity to tyrosinase in the melanocyte with inhibition rates of 23.83%, which was better than kojic acid and arbutin (19.21% and 20.45%) at the same concentration. In the anti-melanogenesis experiment, compounds 8 and 13 had better anti-melanin effects than kojic acid from 25 µM to 100 µM. In summary, the results indicated that compounds 8, 13 and 14 had better tyrosinase inhibitory activity and anti-melanogenesis activity. Especially, the compound 13 has potentiality to develop novel tyrosinase inhibitors and whitening agents. The docking studies results revealed that the functional group of compound 13 mostly depends on the phenolic hydroxyl moiety, and its hydroxyl group did not insert into the active site of tyrosinase, which was in agreement with the results of the kinetics study.


Assuntos
Acetofenonas/farmacologia , Cinamatos/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Acetofenonas/química , Animais , Cinamatos/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Camundongos , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
J Ethnopharmacol ; 264: 113096, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32693116

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Constipation is a functional gastrointestinal disorder and one of the most prevalent conditions encountered in primary care settings. Rhubarb navel dressings have been used for more than 2,000 years in Chinese medicine to treat constipation. However, the effect of topical rhubarb administration has still not been well recognized and this strategy is not yet established as an evidence-based approach. AIM OF THE STUDY: In this study, we performed a prospective multicentric randomized controlled trial to evaluate the efficacy and safety of rhubarb navel plasters for patients with chronic constipation. MATERIALS AND METHODS: A total of 374 patients from six teaching hospitals were prospectively included between 09/2016 and 10/2017 in the study based on Rome III criteria. All participants were randomly assigned (1:1) into verum/placebo group and given either Rheum officinale rhubarb powder or a placebo flour stick on the navel for 6 h/day/8 days. Primary outcome measures were the Cleveland Constipation Score (CCS) for the feces condition and Bristol Stool Scale (BSS) for stool consistency and 24 h defecation frequency. RESULTS: The groups demonstrated no statistical differences in demographic data, clinical diagnoses and concomitant medication at baseline. In patients treated with the verum CCS was 5.61 (day 8, 95% CI 5.15-6.07) compared to 8.62 (95% CI 8.07-9.18) in placebo-treated controls (P < 0.001). The mean change of CCS at the end of treatment (day 8 versus [vs] day 0) was 6.04 in verum-treated vs 2.73 in placebo-treated controls (P < 0.001). Also 24 h defecation frequency (BSS) showed superior results (day 5: 0.84 vs 0.62, 95% CI 0.67-0.80, P < 0.001; day 6: 0.82 vs 0.60, 95% CI 0.64-0.78, P < 0.01 and day 8: 0.82 vs 0.60, 95% CI 0.64-0.78, P < 0.01) and better BSS type classification during treatment than controls (P < 0.05). No significant differences in adverse events between both groups became obvious. CONCLUSION: Rhubarb navel plaster administration over an 8-day-treatment period resulted in significantly improved bowel function as demonstrated by the CCS, 24 h defecating frequency and BSS. Our results suggest that rhubarb navel plasters represent a feasible, safe and efficient application route for the treatment of patients suffering from chronic constipation.


Assuntos
Constipação Intestinal/diagnóstico , Constipação Intestinal/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Extratos Vegetais/administração & dosagem , Rheum , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/isolamento & purificação , Estudos Prospectivos , Resultado do Tratamento
13.
J Am Chem Soc ; 142(51): 21292-21297, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33315367

RESUMO

A series of arene-bridged dithorium complexes was synthesized via the reduction by potassium graphite of a Th(IV) precursor in the presence of arenes. All these compounds adopt an inverse-sandwich structure, with the arene bridging two thorium centers in a µ-η6,η6-mode. Structural and spectroscopic data support the assignment of two Th(IV) ions and an arene tetraanion, which is an aromatic structure according to Hückel's rule. Arene exchange reactions revealed that the stability of the corresponding compounds follows the series naphthalene ≪ toluene < benzene ≈ biphenyl. Reactivity studies showed that they function as four-electron reductants capable to reduce anthracene, cyclooctatetraene, alkynes, and azobenzene, while a mononuclear thorium anthracene complex could reduce benzene. Density functional theory calculations unveiled that the bonding interactions consist of δ bonds between thorium 6d and 5f orbitals and arene π* orbitals, showing a significant covalent character, able to stabilize highly reduced arene ligands.

14.
J Food Sci ; 85(6): 1793-1798, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32449952

RESUMO

To improve stability of peanut butter, rice bran wax (RBX) was added into peanut butter as a stabilizer by formation of organogel. Effects of addition of RBX, heating temperature, and cooling temperature on stabilization effect of peanut butter by RBX were investigated. The optimum conditions were as follow: addition of RBX at 4.0 wt%; heating temperature at 85 °C, and cooling temperature at 20 °C. Under the optimum conditions, the oil loss of peanut butter decreased from 12.19% to 4.04%, and the adhesiveness of peanut butter increased from 23.5 to 165.9 g·s. After storage for 25 weeks, the acid value (AV) of peanut butter prepared under the optimum conditions increased from 0.65  to 0.80 mg/g, and the peroxide value (PV) increased from 0.116 to 0.127 meq/kg. However, the AV of natural peanut butter increased to 1.73 mg/g, and PV increased to 0.178 meq/kg. The confocal laser scanning microscope images showed that the cooling temperature significantly affected crystallization of RBX and distribution of solid particles. When RBX formed needle-like crystals and peanut solid particles were evenly distributed in the oil phase, stable peanut butter was obtained. These results suggested that the RBX was an effective stabilizer for peanut butter. PRACTICAL APPLICATION: Oil separation often occurred to peanut butter during storage, which reduced the sensory quality of peanut butter and shortened its shelf life. This study stabilized peanut butter by addition of RBX based on the formation of organogel, which was of great practical significance to improve the shelf life of peanut butter.


Assuntos
Arachis/química , Aditivos Alimentares/análise , Manipulação de Alimentos/métodos , Oryza/química , Extratos Vegetais/química , Ceras/análise , Cristalização , Temperatura
15.
J Nat Prod ; 83(5): 1453-1460, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32319765

RESUMO

An enantiomeric pair of rare cyperane-type sesquiterpenoids, (+)- and (-)-gracilistones C (1a, 1b), together with a novel norsesquiterpenoid, gracilistone D (2), bearing a bicyclic lactone system were isolated from the root bark of Acanthopanax gracilistylus using LC-MS-IT-TOF analyses. The structures and absolute configurations of 1a, 1b, and 2 were elucidated by 1D and 2D NMR spectroscopy, X-ray diffraction, and ECD spectroscopic methods. Intermediate 1b suggests a possible biosynthesis process involving compound 2. The bioassay results showed that compounds 1a, 1b, and 2 exhibited significant inhibitory effects against lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells, with IC50 values of 7.7 ± 0.6, 6.8 ± 1.5, and 2.6 ± 0.4 µM, respectively. Additional docking analyses provided some perspective of this activity in human inducible nitric oxide synthase.


Assuntos
Araliaceae/química , Óxido Nítrico/antagonistas & inibidores , Casca de Planta/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Animais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Células RAW 264.7 , Difração de Raios X
16.
Tree Physiol ; 40(9): 1277-1291, 2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32348504

RESUMO

Little is known about the physiological and molecular mechanisms underlying magnesium (Mg)-deficiency-induced enlargement, cracking and lignification of midribs and main lateral veins of Citrus leaves. Citrus sinensis (L.) Osbeck seedlings were irrigated with nutrient solution at a concentration of 0 (Mg-deficiency) or 2 (Mg-sufficiency) mM Mg(NO3)2 for 16 weeks. Enlargement, cracking and lignification of veins occurred only in lower leaves, but not in upper leaves. Total soluble sugars (glucose + fructose + sucrose), starch and cellulose concentrations were less in Mg-deficiency veins of lower leaves (MDVLL) than those in Mg-sufficiency veins of lower leaves (MSVLL), but lignin concentration was higher in MDVLL than that in MSVLL. However, all four parameters were similar between Mg-deficiency veins of upper leaves (MDVUL) and Mg-sufficiency veins of upper leaves (MSVUL). Using label-free, liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, we identified 1229 and 492 differentially abundant proteins (DAPs) in MDVLL vs MSVLL and MDVUL vs MSVUL, respectively. Magnesium-deficiency-induced alterations of Mg, nonstructural carbohydrates, cell wall components, and protein profiles were greater in veins of lower leaves than those in veins of upper leaves. The increased concentration of lignin in MDVLL vs MSVLL might be caused by the following factors: (i) repression of cellulose and starch accumulation promoted lignin biosynthesis; (ii) abundances of proteins involved in phenylpropanoid biosynthesis pathway, hormone biosynthesis and glutathione metabolism were increased; and (iii) the abundances of the other DAPs [viz., copper/zinc-superoxide dismutase, ascorbate oxidase (AO) and ABC transporters] involved in lignin biosynthesis were elevated. Also, the abundances of several proteins involved in cell wall metabolism (viz., expansins, Rho GTPase-activating protein gacA, AO, monocopper oxidase-like protein and xyloglucan endotransglucosylase/hydrolase) were increased in MDVLL vs MSVLL, which might be responsible for the enlargement and cracking of leaf veins.


Assuntos
Citrus sinensis , Citrus , Cromatografia Líquida , Magnésio , Folhas de Planta , Raízes de Plantas , Espectrometria de Massas em Tandem
17.
Plants (Basel) ; 9(3)2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121140

RESUMO

This present study examined excess copper (Cu) effects on seedling growth, leaf Cu concentration, gas exchange, and protein profiles identified by a two-dimensional electrophoresis (2-DE) based mass spectrometry (MS) approach after Citrus sinensis and Citrus grandis seedlings were treated for six months with 0.5 (control), 200, 300, or 400 µM CuCl2. Forty-one and 37 differentially abundant protein (DAP) spots were identified in Cu-treated C. grandis and C. sinensis leaves, respectively, including some novel DAPs that were not reported in leaves and/or roots. Most of these DAPs were identified only in C. grandis or C. sinensis leaves. More DAPs increased in abundances than DAPs decreased in abundances were observed in Cu-treated C. grandis leaves, but the opposite was true in Cu-treated C. sinensis leaves. Over 50% of DAPs were associated with photosynthesis, carbohydrate, and energy metabolism. Cu-toxicity-induced reduction in leaf CO2 assimilation might be caused by decreased abundances of proteins related to photosynthetic electron transport chain (PETC) and CO2 assimilation. Cu-effects on PETC were more pronounced in C. sinensis leaves than in C. grandis leaves. DAPs related to antioxidation and detoxification, protein folding and assembly (viz., chaperones and folding catalysts), and signal transduction might be involved in Citrus Cu-toxicity and Cu-tolerance.

18.
Environ Pollut ; 262: 114303, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32155556

RESUMO

Low pH and aluminum (Al)-toxicity often coexist in acidic soils. Citrus sinensis seedlings were treated with nutrient solution at a pH of 2.5, 3.0, 3.5 or 4.0 and an Al concentration of 0 or 1 mM for 18 weeks. Thereafter, malate, citrate, isocitrate, acid-metabolizing enzymes, and nonstructural carbohydrates in roots and leaves, and release of malate and citrate from roots were measured. Al concentration in roots and leaves increased under Al-toxicity, but it declined with elevating nutrient solution pH. Al-toxicity increased the levels of glucose, fructose, sucrose and total soluble sugars in leaves and roots at each given pH except for a similar sucrose level at pH 2.5-3.0, but it reduced or did not alter the levels of starch and total nonstructural carbohydrates (TNC) in leaves and roots with the exception that Al improved TNC level in roots at pH 4.0. Levels of nonstructural carbohydrates in roots and leaves rose with reducing pH with a few exceptions with or without Al-toxicity. A potential model for the possible role of root organic acid (OA) metabolism (anions) in C. sinensis Al-tolerance was proposed. With Al-toxicity, the elevated pH upregulated the OA metabolism, and increased the flow of carbon to OA metabolism, and the accumulation of malate and citrate in roots and subsequent release of them, thus reducing root and leaf Al and hence eliminating Al-toxicity. Without Al-toxicity, low pH stimulated the exudation of malate and citrate, an adaptive response of Citrus to low pH. The interactive effects of pH and pH on OA metabolism were different between roots and leaves.


Assuntos
Citrus sinensis , Citrus , Alumínio , Ânions , Concentração de Íons de Hidrogênio , Folhas de Planta , Raízes de Plantas
19.
Nat Prod Res ; : 1-7, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32208773

RESUMO

Two new pregnane alkaloids, (20S)-20α-cinnamoylamino-3ß-dimethylamino-5-en-pregnane (1) and (20S)-20α-cinnamoylamino-3ß-dimethylamino-pregnane (2), and four known alkaloids (+)-(20S)-20-(dimethylamino)-3-(3'R-isopropyl)-lactam-5α-pregn-2-en-4-one (3), axillaridine A (4), pachysamine M (5) and 20α-dimethylamino-16ß-hydroxy-3ß-senecioylamino-pregn-5-ene (6) were obtained from the whole herb of Pachysandra terminalis Sieb. et Zucc. Their structures were determined by various spectral techniques and computed electronic circular dichroism (ECD) data. Compounds 1-4 were tested for cytotoxicity against three human tumor cell lines and a human umbilical vein endothelial cell (HUVEC) line. Compound 4 exhibited moderate cytotoxicity against MCF-7, U251 and A549 cells with IC50 values of 15.01 ± 0.47 µM, 20.13 ± 1.34 µM and 20.04 ± 1.16 µM, respectively; compounds 1-3 showed weak cytotoxic activity against three tumor cells.

20.
J Nanosci Nanotechnol ; 20(7): 4533-4536, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31968514

RESUMO

The hot-injection method was used for the synthesis of ternary metal chalcogenide nanocrystals (NCs) CuInS2 (CIS); this was achieved by using the metal precursors (copper iodide and indium acetate) and four different types of sulfur precursor solutions. It was discovered that CIS NCs synthesized with different sulfur precursor solutions exhibited the chalcopyrite structure with similar particle sizes of ~4.2 nm. As a comparison, CIS NCs synthesized using ODE-S precursor displayed an enhanced luminescence intensity and a long PL decay lifetime, which could be considered as an evidence of improved interior crystallinity.

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