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1.
Plant Biotechnol J ; 22(5): 1164-1176, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38070185

RESUMO

Soybean is a short-day plant that typically flowers earlier when exposed to short-day conditions. However, the identification of genes associated with earlier flowering time but without a yield penalty is rare. In this study, we conducted genome-wide association studies (GWAS) using two re-sequencing datasets that included 113 wild soybeans (G. soja) and 1192 cultivated soybeans (G. max), respectively, and simultaneously identified a candidate flowering gene, qFT13-3, which encodes a protein homologous to the pseudo-response regulator (PRR) transcription factor. We identified four major haplotypes of qFT13-3 in the natural population, with haplotype H4 (qFT13-3H4) being lost during domestication, while qFT13-3H1 underwent natural and artificial selection, increasing in proportion from 4.5% in G. soja to 43.8% in landrace and to 81.9% in improve cultivars. Notably, most cultivars harbouring qFT13-3H1 were located in high-latitude regions. Knockout of qFT13-3 accelerated flowering and maturity time under long-day conditions, indicating that qFT13-3 functions as a flowering inhibitor. Our results also showed that qFT13-3 directly downregulates the expression of GmELF3b-2 which is a component of the circadian clock evening complex. Field trials revealed that the qft13-3 mutants shorten the maturity period by 11 days without a concomitant penalty on yield. Collectively, qFT13-3 can be utilized for the breeding of high-yield cultivars with a short maturity time suitable for high latitudes.


Assuntos
Estudo de Associação Genômica Ampla , Glycine max , Glycine max/genética , Melhoramento Vegetal , Haplótipos/genética , Fotoperíodo , Flores/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética
2.
J Nat Prod ; 87(1): 132-140, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38157445

RESUMO

Mylnudones A-G (1-7), unprecedented 1,10-seco-aromadendrane-benzoquinone-type heterodimers, and a highly rearranged aromadendrane-type sesquiterpenoid (8), along with four known analogs (9-12), were isolated from the liverwort Mylia nuda. Compounds 1-6 and 7, bearing tricyclo[6.2.1.02,7] undecane and tricyclo[5.3.1.02,6] undecane backbones, likely formed via a Diels-Alder reaction and radical cyclization, respectively. Their structures were determined by spectroscopic analysis, computational calculation, and single-crystal X-ray diffraction analysis. Dimeric compounds displayed cytoprotective effects against glutamic acid-induced neurological deficits.


Assuntos
Alcanos , Hepatófitas , Sesquiterpenos de Guaiano , Sesquiterpenos , Hepatófitas/química , Estrutura Molecular , Sesquiterpenos/farmacologia , Sesquiterpenos/química , China
3.
Int Nurs Rev ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477788

RESUMO

AIM: To evaluate the mediating roles of occupational resilience and the moderationg role of perceived organizational support in the relationship between career calling and nurse burnout. BACKGROUND: Burnout is a frequent and serious problem in the field of nursing, and it poses a serious threat to both nurses' health and patient safety. Although many studies have described the links between burnout, career calling, and occupational resilience, little is known about the actual mechanisms between career calling and nurse burnout. METHODS: A cross-sectional study of 615 nurses in China was conducted using a convenience sampling method. The data were analyzed using descriptive statistics and Pearson correlation analysis. Hypotheses were tested using structural equation models and bootstrapping methods. STROBE guidelines were followed. RESULTS: Career calling was found to be negatively associated with nurse burnout, and occupational resilience mediated the relationship between career calling and burnout. Additionally, perceived organizational support was found to play a moderating role in the relationship between occupational resilience and burnout. CONCLUSION: Career calling can reduce burnout by increasing nurses' levels of occupational resilience, and perceived organizational support moderates this mechanism. Hence, policies focused on encouraging and sustaining career calling should be provided by nurse managers in order to enhance stress resistance and reduce burnout.

4.
Chem Biodivers ; 19(9): e202200559, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35843891

RESUMO

An unprecedented 4,9-seco-oplopanane (1), two undescribed drimane epimers (2 and 3), and five known drimane sesquiterpenoids (4-8) were isolated from the Chinese liverwort Lejeunea flava (Sw.) Nees. The structures of the new sesquiterpenoids were determined using nuclear magnetic resonance spectroscopy, electronic circular dichroism calculations, and single-crystal X-ray diffraction measurements. The inhibitory capacity of the new compounds against nitric oxide production in lipopolysaccharide-induced RAW 264.7 murine macrophages, along with the cytotoxicity of the new compounds against A549 and HepG-2 human cancer cell lines, were discussed.


Assuntos
Anemone , Hepatófitas , Sesquiterpenos , Animais , China , Hepatófitas/química , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Sesquiterpenos/farmacologia
5.
J Integr Plant Biol ; 64(3): 632-648, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34914170

RESUMO

Innovations in genomics have enabled the development of low-cost, high-resolution, single nucleotide polymorphism (SNP) genotyping arrays that accelerate breeding progress and support basic research in crop science. Here, we developed and validated the SoySNP618K array (618,888 SNPs) for the important crop soybean. The SNPs were selected from whole-genome resequencing data containing 2,214 diverse soybean accessions; 29.34% of the SNPs mapped to genic regions representing 86.85% of the 56,044 annotated high-confidence genes. Identity-by-state analyses of 318 soybeans revealed 17 redundant accessions, highlighting the potential of the SoySNP618K array in supporting gene bank management. The patterns of population stratification and genomic regions enriched through domestication were highly consistent with previous findings based on resequencing data, suggesting that the ascertainment bias in the SoySNP618K array was largely compensated for. Genome-wide association mapping in combination with reported quantitative trait loci enabled fine-mapping of genes known to influence flowering time, E2 and GmPRR3b, and of a new candidate gene, GmVIP5. Moreover, genomic prediction of flowering and maturity time in 502 recombinant inbred lines was highly accurate (>0.65). Thus, the SoySNP618K array is a valuable genomic tool that can be used to address many questions in applied breeding, germplasm management, and basic crop research.


Assuntos
Glycine max , Polimorfismo de Nucleotídeo Único , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Genômica , Genótipo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética , Glycine max/genética
6.
J Nat Prod ; 84(5): 1459-1468, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33913326

RESUMO

An EtOH extract of the Chinese liverwort Radula apiculata showed cytotoxic activity against the A549 lung cancer cell line. Bioassay-guided fractionation led to the isolation of 19 prenylated bibenzyls, including eight previously unknown dimeric prenylated bibenzyls [radulapins A-H (1-8)], four new prenylated bibenzyls (9-12), and seven known compounds (13-19). Compounds 1-11 were analyzed as racemates by chiral-phase separation. Their structures were determined by detailed analysis of their spectroscopic data and by single-crystal X-ray diffraction, chiral resolutions, and electronic circular dichroism measurements. Using an MTT assay, these dimers (1-8) showed significant cytotoxic activity against a panel of human cancer cell lines. Further investigation revealed that compound 4 induces PC-3 cell death via mitochondrial-derived apoptosis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Hepatófitas/química , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Bibenzilas/isolamento & purificação , China , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estrutura Molecular , Células PC-3 , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Prenilação , Estereoisomerismo
7.
Angew Chem Int Ed Engl ; 60(28): 15286-15290, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33876516

RESUMO

An enantioselective synthetic approach for preparing manginoids and guignardones, two types of biogenetically related meroterpenoids, is reported. This bioinspired and divergent synthesis employs an oxidative 1,3-dicarbonyl radical-initiated cyclization and cyclodehydration of the common precursor to forge the central ring of the manginoids and guignardones, respectively, at a late stage. Key synthetic steps include silica-gel-promoted semipinacol rearrangement to form the 6-oxabicyclo[3.2.1]octane skeleton and the Suzuki-Miyaura reaction of vinyl bromide to achieve fragment coupling. This synthesis protocol enables the asymmetric syntheses of four fungal meroterpenoids from commercially available materials.

8.
Angew Chem Int Ed Engl ; 59(45): 19919-19923, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32696611

RESUMO

A divergent synthetic approach to biogenetically related diterpenoids such as ent-kauranes, ent-trachylobanes, ent-beyerane, and ent-atisane has been developed. The unified synthetic route involves the De Mayo reaction to rapidly generate the bicyclo[3.2.1]-octane moiety of ent-kaurane. The key reactions also include bioinspired nucleophilic cyclopropanation generating the [3.2.1.02,7 ]-tricyclic core of ent-trachylobane and regioselective cyclopropane fragmentation furnishing ent-beyerane and ent-atisane through the nucleophilic attack and protonation of the cyclopropane ring. This strategy enables the asymmetric total syntheses of six diterpenoids from the commercially available geraniol.

9.
Chemistry ; 23(9): 2031-2034, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28012253

RESUMO

The causes for the title reaction to be limited to only the alkenes with an unsubstituted terminal alkenic carbon were explored. In some "failed" cases the cycloaddition products actually formed but rearranged concurrently. An oxygen atom or a N-Boc (Boc=tert-butyloxycarbonyl) group at the double bond was proven essential for acquisition of intact [3+2] cycloaddition products from 1,2-disubstituted ethylenes.

10.
Chemistry ; 23(9): 2026-2030, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27957781

RESUMO

Two monocyclic members in the gracilioether family were synthesized in only three steps. The monocyclic products were further elaborated into advanced precursors to hippolachnin A and gracilioether E, respectively. Gracilioether F and the alleged structure for gracilioether I were also synthesized using a late-stage C(sp3 )-H thermo-oxidation.


Assuntos
Éteres Cíclicos/química , Compostos Heterocíclicos com 3 Anéis/química , Policetídeos/química , Reação de Cicloadição , Éteres Cíclicos/síntese química , Compostos Heterocíclicos com 3 Anéis/síntese química , Conformação Molecular , Oxirredução , Policetídeos/síntese química , Estereoisomerismo , Temperatura
12.
Am J Cancer Res ; 13(3): 802-817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034207

RESUMO

Cancer stem cells (CSCs) are a subset of cancer cells with stem cell characteristics. The discovery of CSCs has opened a new era for cancer research. CSCs not only play a critical role in tumorigenesis, but also are responsible for the failure of cancer treatments. Here, we performed weighted gene co-expression network analysis (WGCNA) to identify key stemness genes and prognostic signatures using the data of an Asian liver cancer patient cohort and a White liver cancer patient cohort in The Cancer Genome Atlas (TCGA) database. To compare the difference in tumorigenesis between the Asian patients and the White patients, the prognostic value of the key genes from the Asian patients was evaluated in the White patient cohort and vice versa. We found that some key genes could predict the survival of the patients regardless of race. In addition, the key genes, NUCB2 and KLF4A, were selected from Asian patients and White patients, respectively, for further experimental validation. Knocking down NUCB2 could inhibit the activity of the AKT/mTOR signaling pathway and reverse the epithelial-mesenchymal transition (EMT) in liver cancer cells. We also confirmed that the knockdown of KLF4A suppressed ABCG2 activity and reduced the side population (SP) in liver cancer cells for the first time. Our results suggest that the stemness index is a useful method to identify key genes in tumorigenesis. Compared to the analysis for all patients, applying this index to the analysis of the patients of different races will provide more potential therapeutic targets for cancer treatment.

13.
Eur J Med Chem ; 259: 115693, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37531745

RESUMO

Epothilone B (Epo B) is a potent antitumor natural product with sub-nanomolar anti-proliferation action against several human cancer cells. However, poor selectivity to tumor cells and unacceptable therapeutic windows of Epo B and its analogs are the major obstacles to their development into clinical drugs. Herein, we present self-assembled nanomicelles based on an amphiphilic carbohydrate-Epo B conjugate that is inactive until converted to active Epo B within the tumor. Four Epo B-Rhamnose conjugates linked via two linkers containing a disulfide bond that is sensitive to GSH were synthesized. Conjugate 34 can self-assemble into nanomicelles with a high concentration of Rha on the surface, allowing for better tumor targeting. After internalization by cancer cells, the disulfide bond can be cleaved in the presence of high levels of GSH to release active Epo B, thereby exhibiting significant anticancer efficiency and selectivity in vitro and in vivo.


Assuntos
Epotilonas , Nanopartículas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Carboidratos/uso terapêutico , Dissulfetos , Linhagem Celular Tumoral , Nanopartículas/química
14.
Phytochemistry ; 214: 113796, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499849

RESUMO

- Seven previously undescribed ent-eudesmane sesquiterpenoids (1-7), as well as seven known analogs (8-14), were isolated from the Chinese liverwort Chiloscyphus polyanthus var. rivularis. Their structures were established based on comprehensive spectroscopy analysis, electronic circular dichroism calculations, as well as biosynthetic considerations. The cytotoxicity against HepG2 (Human hepatocellular carcinomas) cancer cell line, and antifungal activity against Candida albicans SC5314 of all isolated ent-eudesmane sesquiterpenoids were preliminarily tested, results showed that the tested compounds did not display obvious cytotoxicity and antifungal activities under the tested concentration.


Assuntos
Antifúngicos , Antineoplásicos , Hepatófitas , Sesquiterpenos de Eudesmano , Sesquiterpenos , Antifúngicos/farmacologia , Antifúngicos/química , China , Hepatófitas/química , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos de Eudesmano/farmacologia , Sesquiterpenos de Eudesmano/química , Células Hep G2/efeitos dos fármacos , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia
15.
Phytochemistry ; 212: 113702, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37149119

RESUMO

Three unprecedented ent-labdane and pallavicinin based dimers pallamins A-C formed via [4 + 2] Diels-Alder cycloaddition, together with eight biosynthetically related monomers were isolated from Pallavicinia ambigua. Their structures were determined by the extensive analysis of HRESIMS and NMR spectra. The absolute configurations of the labdane dimers were determined by single crystal X-ray diffraction of the homologous labdane units, and 13C NMR and ECD calculations. Moreover, a preliminary evaluation of the anti-inflammatory activities of the isolated compounds was performed using the zebrafish model. Three of the monomers demonstrated significant anti-inflammatory activity.


Assuntos
Diterpenos , Hepatófitas , Animais , Diterpenos/farmacologia , Diterpenos/química , Hepatófitas/química , Estrutura Molecular , Peixe-Zebra , China
16.
Stem Cells Int ; 2022: 3611677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342431

RESUMO

Cancer stem cell (CSC) refers to cancer cells with stem cell properties, that is, they have the ability of "self-renewal" and "differentiation." Cancer stem cells exist in cancer cells and are the "culprit" of cancer recurrence and metastasis. It is difficult to be found because of its small amount, and it is difficult for anticancer drugs to produce effects on it. At present, the isolation and identification of cancer stem cells from many solid tumors are still quite difficult, mainly due to the lack of specific molecular markers of cancer stem cells. In this review, cancer stem cell surface markers and functional markers in urinary system were summarized. These markers can provide molecular targets for cancer therapy.

17.
ACS Omega ; 6(45): 30811-30817, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34805709

RESUMO

A practical route to 2-(2-(2-methyl-1,3-dioxolan-2-yl)ethyl)cyclohexan-1-one was developed, featuring the use of inexpensive starting materials/reagents and readily attainable reaction conditions. The overall transformation was achieved in 53% yield with one chromatographic purification via NaOH-mediated aldol condensation, ethylene glycol protection of the ketone group in the presence of HC(OEt)3/concd HCl, saturation of the C=C bond and the benzene ring with Al-Ni alloy in aqueous KOH, and oxidation of the intermediate cyclohexanol with aqueous NaClO/TEMPO/KBr.

18.
Org Lett ; 23(23): 9073-9077, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34797080

RESUMO

Herein, we have developed two types of photoredox-catalyzed cascade reactions using diaryliodonium salts for the concise synthesis of norascyronone A and ß-eudesmol. A rationally designed photoredox-catalyzed arylation/cyclization/Friedel-Crafts cascade reaction of enone was exploited to generate the norascyronone polycyclic skeleton. A visible-light-induced radical cyclization/acyloxy-migration reaction was explored to forge the decalin skeleton of eudesmol, and mechanistic studies indicated the reaction was initiated by one-electron oxidation of the enol ester.

19.
Reprod Sci ; 28(8): 2147-2160, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33079330

RESUMO

Oxidative stress-induced granulosa cell (GC) death is a major cause of follicular atresia. As the major types of programmed cell death, autophagy and apoptosis have been observed in response to H2O2-mediated oxidative stress and have been demonstrated to be responsible for porcine GC death. To date, however, the cellular reactions linking autophagy to the apoptosis of porcine GC under oxidative stress are still poorly understood. Porcine GC were treated with H2O2, and autophagic flux was examined by western blotting. Cell viability and cell death assays were performed after cotreatment of porcine GC with autophagy activator (rapamycin) or inhibitor (3-methyladenine, 3-MA) together with H2O2. We revealed that short exposure (1-3 h) of porcine GC to H2O2 dramatically increased autophagic flux (1.8- to 2.5-fold over that in the control), whereas 6-12 h prolonged treatment decreased autophagy but elevated the caspase-3 activity and GC apoptotic rate. Furthermore, we showed that pretreatment with rapamycin exacerbated H2O2-mediated cytotoxicity and caspase-3 activation but that 3-MA or siRNAs specific for Beclin 1 and Atg7 genes ameliorated H2O2-mediated GC apoptosis. Together, our results indicate that autophagy plays a pivotal role in H2O2-mediated porcine GC apoptosis. Importantly, we show that the early induction of autophagic flux contributes to oxidative stress-induced apoptosis in porcine GC. The results also suggest that regulating the autophagy response in porcine GC under oxidative stress might be a new strategy for abnormal follicular atresia.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Atresia Folicular/metabolismo , Células da Granulosa/metabolismo , Estresse Oxidativo/fisiologia , Animais , Caspase 3/metabolismo , Sobrevivência Celular/fisiologia , Feminino , Malondialdeído/metabolismo , Suínos
20.
Front Pediatr ; 8: 599044, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33553069

RESUMO

Objective: This study was conducted to evaluate the potential genetic and non-genetic factors contributing to plasma trough concentration-to-dose (C 0/D) ratio of valproic acid (VPA) in pediatric patients with epilepsy. Study Design: A single-center, retrospective cohort study was performed by collecting data from 194 children aged 1-14 years between May 2018 and November 2018. The oral solution (n = 135) group and the sustained-release (SR) tablet group (n = 59) were defined, and the plasma VPA C 0 was measured. Twenty-six single-nucleotide polymorphisms (SNPs) were chosen for genotyping with the MassARRAY system. A multiple logistic regression model was used for data analysis. Results: Body weight (BW) and age were positively correlated with the C 0/D ratio in 194 patients, but the positive correlation disappeared after the patients were divided into oral solution and SR tablet subgroups. The average C 0/D ratio was significantly increased by 2.11-fold (P = 0.000) in children who took VPA SR tablets compared with children who were administered VPA oral solutions. No significant association between genetic variants and the C 0/D ratio was found, even for the five well-studied SNPs, namely UGT2B7 G211T, C802T, C161T, T125C, and CYP2C9 * 3 A1075C. However, a significant association between the C 0/D ratio and UGT1A6/9 Del>A (rs144486213) was observed in the VPA oral solution group, but not in the VPA SR tablet group. Conclusions: The dosage forms of sodium valproate, rather than BW, age, or genetic polymorphisms, significantly affected the VPA C 0/D ratios in pediatric patients with epilepsy. Based on our findings, switching the dosage form between solution and SR tablet should be performed cautiously. Total daily dose adjustment should be considered, and the plasma concentration, seizure-control effect, and adverse drug reaction should also be monitored very closely.

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