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1.
J Org Chem ; 89(10): 7216-7224, 2024 May 17.
Article En | MEDLINE | ID: mdl-38693864

An organoselenium-catalyzed C2,3-diarylation of unprotected N-H indoles with electron-rich aromatics has been developed. This one-pot multicomponent tandem cross-dehydrogenation coupling reaction allows for the incorporation of two different aromatic groups to indoles. More importantly, this approach offers significant advantages, including a high atom and step economy, eliminating the need for prepreparation of the reaction substrates, streamlining the synthetic process and enhancing its practicality. Overall, this organoselenium-catalyzed C2,3-diarylation reaction presents an efficient and versatile strategy for the functionalization of indole derivatives.

2.
Chem Commun (Camb) ; 60(34): 4613-4616, 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38587256

We report an innovative synthetic strategy for the generation of polysubstituted indoles from indolines, aryldiazonium salts, and azoles. The methodology encompasses an electrophilic substitution reaction affording C5-indoline intermediates which undergo an iodine-mediated oxidative transformation coupled with C-H functionalization to yield the indole derivatives.

3.
Physiol Plant ; 176(2): e14275, 2024.
Article En | MEDLINE | ID: mdl-38566267

Developing and cultivating rice varieties is a potent strategy for reclaiming salinity-affected soils for rice production. Nevertheless, the molecular mechanisms conferring salt tolerance, especially in conventional high-yield japonica rice varieties, remain obscure. In this study, Zhendao 23309 (ZD23309) exhibited significantly less grain yield reduction under a salt stress gradient than the control variety Wuyunjing 30 (WYJ30). High positive correlations between grain yield and dry matter accumulation at the jointing, heading and maturity stages indicated that early salt tolerance performance is a crucial hallmark for yield formation. After a mild salt stress (85 mM NaCl) of young seedlings, RNA sequencing (RNA-seq) of shoot and root separately identified a total of 1952 and 3647 differentially expressed genes (DEGs) in ZD23309, and 2114 and 2711 DEGs in WYJ30, respectively. Gene ontology (GO) analysis revealed numerous DEGs in ZD23309 that play pivotal roles in strengthening salt tolerance, encompassing the response to stimulus (GO:0050896) in shoots and nucleoside binding (GO:0001882) in roots. Additionally, distinct expression patterns were observed in a fraction of genes in the two rice varieties under salt stress, corroborating the efficacy of previously reported salt tolerance genes. Our research not only offers fresh insights into the differences in salt stress tolerance among conventional high-yield rice varieties but also unveils the intricate nature of salt tolerance mechanisms. These findings lay a solid groundwork for deciphering the mechanisms underlying salt tolerance.


Oryza , Oryza/physiology , Gene Expression Profiling , Salt Stress , Seedlings/physiology , Salt Tolerance/genetics
5.
Front Plant Sci ; 15: 1273774, 2024.
Article En | MEDLINE | ID: mdl-38352646

Introduction: The panicle fertilization strategy for japonica and indica rice under wheat straw return (SR) has not been updated, especially on the elaboration of their impacts on spikelet differentiation and degeneration. This study aimed to verify the hypothesis that SR increases spikelet number by reducing spikelet degeneration and to explore the possibility of simplifying panicle fertilization. Methods: In three consecutive years, four varieties of japonica and indica rice were field-grown in Yangzhou, Jiangsu Province, China. Six panicle fertilization rates and split treatments were applied to SR and no straw return (NR) conditions. Results: The results showed that SR promoted rice yield significantly by 3.77%, and the highest yields were obtained under the T2 (split panicle fertilization at the panicle initiation (PI) and spikelet primordium differentiation (SPD) stages) and T1 (panicle fertilization only at the PI stage) treatments, for indica and japonica rice, respectively. Correlation and path analysis revealed that the number of spikelets per panicle was the most attributable to yield variation. SR significantly increased the concentration of alkali hydrolyzable N in the soil 40 days after rice transplantation, significantly increased the nitrogen accumulation per stem (NA) during the SPD-pollen mother cell meiosis (PMC) stage, and increased the brassinosteroids level in the young panicles at the PMC stage. SR also reduced the degeneration rate of spikelets (DRS) and increased the number of surviving spikelets (NSS). The dry matter accumulation per stem was more important to increasing the NA in japonica rice at the PMC stage, whereas NA was more affected by the N content than the dry matter accumulation in indica rice. In japonica rice, panicle N application once only at the PI stage combined with the N released from SR was enough to improve the plant N content, reduce the DRS, and increase the NSS. For indica rice, split application of N panicle fertilization at both the PI and SPD stages was still necessary to achieve a maximum NSS. Discussion: In conclusion, under wheat SR practice, panicle fertilization could be simplified to once in japonica rice with a significant yield increase, whereas equal splits might still be optimal for indica rice.

6.
Chem Commun (Camb) ; 60(9): 1152-1155, 2024 Jan 25.
Article En | MEDLINE | ID: mdl-38189976

A directing-group-free strategy for oxidative regioselective aminochalcogenation of indolines with amines and dichalconides is presented. This strategy combines tandem coupling sequences and oxidative dehydrogenation methods in a multi-component reaction, enabling the fast construction of a series of C2,3- or C2,5-aminochalcogenated indole derivatives. Moreover, the application of this synthetic approach is demonstrated through the late-stage modification of pharmaceuticals and the derivatization of the products, highlighting its potential and significance.

7.
Chemistry ; 30(9): e202303708, 2024 Feb 12.
Article En | MEDLINE | ID: mdl-38088216

The study on structure-property relationship has been a significant focus in the field of organic molecular luminescence. In the present work, three chiral binaphthyl-based triphenylethylene (HTPE) derivatives were prepared through condensation reactions. Despite their similar structures, these compounds exhibited distinct luminescent properties. Diphenylmethane-derived HTPE displayed dual-state emissions, characterized by dual-wavelength emissions which were insensitive to the polarity of solvents. The dual emissions in solution state could be attributed to the different locally excited (LE) excitons. However, upon aggregation, two stable conformers were generated, probably leading to different emission peaks. In contrast, dibenzocycloheptadiene-derived HTPE aggregates showed only a single emission peak. Surprisingly, fluorene-derived HTPE exhibited obvious luminescence in neither solution nor aggregate states due to inherent π-π interactions. These conclusions were substantiated by X-ray analysis, spectroscopic analysis, and theory calculations. Application studies demonstrated that fluorescence on/off switches could be achieved through exposure to acetone. More importantly, trace amounts of acetone could be detected using luminescent materials in both organic and aqueous phases with a detection limit of 0.08 %. Thus, this work not only presents a strategy for designing chiral triphenylethylene fluorophores but also provides valuable information for dual wavelength emissions resulting from two stable conformations.

8.
Plants (Basel) ; 12(23)2023 Nov 23.
Article En | MEDLINE | ID: mdl-38068583

Reverse transcription quantitative real-time PCR (RT-qPCR) is arguably the most prevalent and accurate quantitative gene expression analysis. However, selection of reliable reference genes for RT-qPCR in rice (Oryza sativa) is still limited, especially for a specific tissue type or growth condition. In this study, we took the advantage of our RNA-seq datasets encompassing data from five rice varieties with diverse treatment conditions, identified 12 novel candidate reference genes, and conducted rigorous evaluations of their suitability across typical rice tissues. Comprehensive analysis of the leaves, shoots, and roots of two rice seedlings subjected to salt (30 mmol/L NaCl) and drought (air-dry) stresses have revealed that OsMED7, OsACT1, and OsOS-9 were the robust reference genes for leaf samples, while OsACT1, OsZOS3-23, and OsGDCP were recommended for shoots and OsMED7, OsOS-9, and OsGDCP were the most reliable reference genes for roots. Comparison results produced by different sets of reference genes revealed that all these newly recommended reference genes displayed less variation than previous commonly used references genes under the experiment conditions. Thus, selecting appropriate reference genes from RNA-seq datasets leads to identification of reference genes suitable for respective rice tissues under drought and salt stress. The findings offer valuable insights for refining the screening of candidate reference genes under diverse conditions through the RNA-seq database. This refinement serves to improve the accuracy of gene expression in rice under similar conditions.

9.
Mol Plant ; 16(11): 1832-1846, 2023 11 06.
Article En | MEDLINE | ID: mdl-37798878

Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most important diseases of rice. Utilization of blast-resistance genes is the most economical, effective, and environmentally friendly way to control the disease. However, genetic resources with broad-spectrum resistance (BSR) that is effective throughout the rice growth period are rare. In this work, using a genome-wide association study, we identify a new blast-resistance gene, Pijx, which encodes a typical CC-NBS-LRR protein. Pijx is derived from a wild rice species and confers BSR to M. oryzae at both the seedling and panicle stages. The functions of the resistant haplotypes of Pijx are confirmed by gene knockout and overexpression experiments. Mechanistically, the LRR domain in Pijx interacts with and promotes the degradation of the ATP synthase ß subunit (ATPb) via the 26S proteasome pathway. ATPb acts as a negative regulator of Pijx-mediated panicle blast resistance, and interacts with OsRbohC to promote its degradation. Consistently, loss of ATPb function causes an increase in NAPDH content and ROS burst. Remarkably, when Pijx is introgressed into two japonica rice varieties, the introgression lines show BSR and increased yields that are approximately 51.59% and 79.31% higher compared with those of their parents in a natural blast disease nursery. In addition, we generate PPLPijx Pigm and PPLPijx Piz-t pyramided lines and these lines also have higher BSR to panicle blast compared with Pigm- or Piz-t-containing rice plants. Collectively, this study demonstrates that Pijx not only confers BSR to M. oryzae but also maintains high and stable rice yield, providing new genetic resources and molecular targets for breeding rice varieties with broad-spectrum blast resistance.


Magnaporthe , Oryza , Plant Proteins/genetics , Plant Proteins/metabolism , Reactive Oxygen Species/metabolism , Seedlings/genetics , Seedlings/metabolism , Disease Resistance/genetics , Genome-Wide Association Study , Plant Breeding , Adenosine Triphosphate/metabolism , Oryza/metabolism , Plant Diseases/genetics , Plant Diseases/microbiology , Magnaporthe/genetics
10.
Immun Inflamm Dis ; 11(10): e1061, 2023 10.
Article En | MEDLINE | ID: mdl-37904714

OBJECTIVE: To uncover the effects of chrysosplenol D (CHD) on the progression of prostate cancer in vitro as well as in mice. METHODS: DU145 and PC-3 cells were treated with increasing doses of CHD for 24, 48, or 72 h. Cell Counting Kit-8 (CCK-8) and colony formation assays were conducted to confirm the effects of CHD on cell viability. Flow cytometry (FCM) and immunostaining assays showed the effects of CHD on cell apoptosis and oxidative stress. Immunoblot was performed to detect the effects of CHD on autophagy. Besides, tumor growth assays were conducted to confirm the role of CHD in tumor growth in mice. GraphPad 6.0 was used for statistical analysis. All data were represented as mean ± SD. p < .05 and the significant difference was indicated by an asterisk. RESULTS: CHD suppressed the viability of prostate cancer cells in CCK-8 assays, decreased colony number in colony formation assays, and induced cell apoptosis in FCM and immunostaining assays. CHD also restrained the oxidative stress with a decreased 2'-7'-dichlorofluorescein diacetate staining intensity. CHD restrained the autophagy of prostate cancer cells, as well as suppressed tumor growth in mice. CONCLUSION: CHD could serve as a drug for prostate cancer.


Prostatic Neoplasms , Humans , Male , Animals , Mice , Reactive Oxygen Species/pharmacology , Cell Line, Tumor , Cell Proliferation , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Autophagy
11.
J Org Chem ; 88(21): 15106-15117, 2023 Nov 03.
Article En | MEDLINE | ID: mdl-37864558

A metal-free one-pot oxidative cross-dehydrogenation coupling reaction for the formation of C-N/C-C bonds at the C2,3-positions of indoles with azoles and quinoxalinones has been developed. The proposed method has several notable features, including metal-free catalysis, the use of N-H free indoles as substrates, ease of operation, mild reaction conditions, and compatibility with a wide range of substrates.

12.
Org Biomol Chem ; 21(34): 6898-6902, 2023 Aug 30.
Article En | MEDLINE | ID: mdl-37581413

A structurally diverse set of chiral pyrazolo[3,4-b]pyridin-6-ones was efficiently prepared in excellent yields with excellent enantioselectivities via N-heterocyclic carbene-catalyzed oxidative [3 + 3] annulation of enals with pyrazol-5-amines. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.

13.
Chemistry ; 29(62): e202301766, 2023 Nov 08.
Article En | MEDLINE | ID: mdl-37550834

Small organic molecules which can emit fluorescence with tunable dual emission bands are significant for fundamental research and broad applications. In this work, two binaphthyl based arylacrylonitrile derivatives with pyrene and triphenylamine unit (BiNp-Py and BiNp-TPA) were designed and synthesized, respectively, featuring chiral backbone and dual AIE-active cyanostyrene-linked chromophores. Excellent fluorescence emissions in a range of solution and solid states were observed with high quantum yields, indicative of the solvatochromism and mechanochromism. More interestingly, dual emission bands were found and tunable by the water fraction in THF, and speculatively attributed to the balancing of intramolecular charge transfer (ICT) and locally excited (LE) emission in solution and aggregate states. Furthermore, the potential application in anti-counterfeiting ink was also explored, indicating the very low concentration (5 ppm) for sufficient distinguishable vision and small colour migration (28 nm) for printing on the filter. The present work provides a new strategy to design organic luminescent structure having widely fluorescent emissions in dual states and a valuable reference for the study of chiral optical materials.

14.
Plant Commun ; 4(5): 100605, 2023 09 11.
Article En | MEDLINE | ID: mdl-37087571

This study reports the creation of herbicide-resistant rice lines via CRISPR-Cas9-mediated editing of the 3' UTR of OsHPPD. Resistance index calculations revealed that two resistant lines, TS8-2#-10 and TS8-8#-6, exhibited 4.8-fold and 3.7-fold greater resistance to HPPD-inhibiting herbicides compared with the wild type, YG3012.


Herbicides , Oryza , CRISPR-Cas Systems/genetics , Oryza/genetics , 3' Untranslated Regions , Herbicides/pharmacology
15.
J Org Chem ; 88(5): 2801-2808, 2023 Mar 03.
Article En | MEDLINE | ID: mdl-36800292

A simple method for the preparation of imidazo[4,5-b]indole-2-thiones from 2-alkynylnitrobenzenes and thioureas is described. In the reaction, a Wittig-like process was triggered by PPh3 and followed by a cyclization step. The products were afforded in yields of 70-98% under mild conditions. Additionally, the 2-alkynylnitrobenzenes were stable and could be prepared via a simple coupling step.

16.
Stroke Vasc Neurol ; 8(3): 238-248, 2023 Jun.
Article En | MEDLINE | ID: mdl-36418056

Stroke imposes a substantial burden worldwide. With the rapid economic and lifestyle transition in China, trends of the prevalence of stroke across different geographic regions in China remain largely unknown. Capitalizing on the data in the National Health Services Surveys (NHSS), we assessed the prevalence and risk factors of stroke in China from 2003 to 2018. In this study, data from 2003, 2008, 2013, and 2018 NHSS were collected. Stroke cases were based on participants' self-report of a previous diagnosis by clinicians. We estimated the trends of stroke prevalence for the overall population and subgroups by age, sex, and socioeconomic factors, then compared across different geographic regions. We applied multivariable logistic regression to assess associations between stroke and risk factors. The number of participants aged 15 years or older were 154,077, 146,231, 230,067, and 212,318 in 2003, 2008, 2013, and 2018, respectively, among whom, 1435, 1996, 3781, and 6069 were stroke patients. The age and sex standardized prevalence per 100,000 individuals was 879 in 2003, 1100 in 2008, 1098 in 2013, and 1613 in 2018. Prevalence per 100,000 individuals in rural areas increased from 669 in 2003 to 1898 in 2018, while urban areas had a stable trend from 1261 in 2003 to 1365 in 2018. Across geographic regions, the central region consistently had the highest prevalence, but the western region has an alarmingly increasing trend from 623/100,000 in 2003 to 1898/100,000 in 2018 (P trend<0.001), surpassing the eastern region in 2013. Advanced age, male sex, rural area, central region, hypertension, diabetes, depression, low education and income level, retirement or unemployment, excessive physical activity, and unimproved sanitation facilities were significantly associated with stroke. In conclusion, the increasing prevalence of stroke in China was primarily driven by economically underdeveloped regions. It is important to develop targeted prevention programs in underdeveloped regions. Besides traditional risk factors, more attention should be paid to nontraditional risk factors to improve the prevention of stroke.


Hypertension , Stroke , Humans , Male , Cross-Sectional Studies , Prevalence , Risk Factors , Stroke/diagnosis , Stroke/epidemiology , Hypertension/epidemiology
17.
PLoS One ; 17(12): e0279254, 2022.
Article En | MEDLINE | ID: mdl-36520873

The ability of insets to react efficiently to fluctuation in temperature is crucial for them to survive in variable surroundings. Rapid cold hardening (RCH) is a process that increase cold tolerance in most insect species. The molecular mechanisms of RCH remain largely unknown, and whether it is associated with transcriptional changes is unclear. In this study, we compared the transcriptomes of Liriomyza trifolii and L. sativae exposed to RCH to investigate the transcript abundance due to RCH in both species. RNA-seq revealed 93,166 assembled unigenes, and 34,303 of these were annotated in the L. trifolii and L. sativae transcriptome libraries. After a 4-h treatment at 1°C (RCH) compared with control, 268 and 606 unigenes were differentially expressed in L. trifolii and L. sativae, respectively. When comparing pupae exposed to 2h cold shock directly with pupae went through 4h acclimation prior to 2h cold shock, 60 and 399 unigenes were differentially expressed in L trifolii and L sativae, respectively. Genes that were commonly expressed in both L. trifolii and L. sativae, included cytochrome P450, cuticular protein, glucose dehydrogenase, solute carrier family 22 and cationic amino acid transporter. Additionally, several pathways including galactose metabolism and peroxisome were significantly enriched during RCH. Our results show that the transcriptional response is correlated with RCH in the pupal stage of the two Liriomyza species, but more transcriptional changes were identified in L sativae than in L. trifolii.


Diptera , Animals , Diptera/genetics , Transcriptome , Pupa/physiology , Gene Expression Profiling , Cold Temperature
18.
Plants (Basel) ; 11(23)2022 Nov 27.
Article En | MEDLINE | ID: mdl-36501299

Buckwheat is an important minor grain crop with medicinal and edible functions. The accurate judgment of buckwheat maturity is beneficial to reduce harvest losses and improve yield. With the rapid development of unmanned aerial vehicle (UAV) technology, it has been widely used to predict the maturity of agricultural products. This paper proposed a method using recursive feature elimination cross-validation (RFECV) combined with multiple regression models to predict the maturity of buckwheat in UAV-RGB images. The images were captured in the buckwheat experimental field of Shanxi Agricultural University in Jinzhong, Northern China, from September to October in 2021. The variety was sweet buckwheat of "Jinqiao No. 1". In order to deeply mine the feature vectors that highly correlated with the prediction of buckwheat maturity, 22 dimensional features with 5 vegetation indexes, 9 color features, and 8 texture features of buckwheat were selected initially. The RFECV method was adopted to obtain the optimal feature vector dimensions and combinations with six regression models of decision tree regression, linear regression, random forest regression, AdaBoost regression, gradient lifting regression, and extreme random tree regression. The coefficient of determination (R2) and root mean square error (RMSE) were used to analyze the different combinations of the six regression models with different feature spaces. The experimental results show that the single vegetation index performed poorly in the prediction of buckwheat maturity; the prediction result of feature space "5" combined with the gradient lifting regression model performed the best; and the R2 and RMSE were 0.981 and 1.70 respectively. The research results can provide an important theoretical basis for the prediction of the regional maturity of crops.

19.
J Org Chem ; 87(18): 12424-12433, 2022 09 16.
Article En | MEDLINE | ID: mdl-36046980

An efficient copper-iodine cocatalyzed intermolecular C-H aminocyanation of indoles with a broad substrate scope has been developed for the first time. This method enables highly step-economic access to 2-amino-3-cyanoindoles in moderate to good yields and provides a complementary strategy for the regioselective difunctionalization of carbon═carbon double bonds of interest in organic synthesis and related areas. Mechanistic studies suggest that these transformations are initiated by iodine-mediated C2-H amination with azoles, followed by copper-catalyzed C3-H cyanation with ethyl cyanoformate.


Indoles , Iodine , Azoles/chemistry , Catalysis , Copper/chemistry , Indoles/chemistry , Iodides , Iodine/chemistry
20.
Psych J ; 11(6): 956-967, 2022 Dec.
Article En | MEDLINE | ID: mdl-35922380

The present study compared an immersive virtual reality-based attentional bias modification (immersive VR-ABM) with the desktop version of the VR-ABM and an immersive virtual reality-based game (immersive VR-game) to examine the possible effect of the immersive presence on self-reported emotional reactions to a stressful task. One hundred and twenty participants were randomly assigned into three groups, and each group received a three-turn induction-intervention training. Anxiety symptoms were assessed at pre-induction, post-induction, and post-training. Results showed that virtual reality-based anxiety was induced and alleviated successfully in all three groups, but only the immersive VR-ABM group showed an accumulated effect on self-reported anxiety across sessions. The attentional bias based on probe latencies indicated no significant change in either the immersive or desktop VR-ABM groups. The present findings support the hypothesized VR-ABM's effect on self-reported anxiety at the immersive presence. The practical implications of using immersive VR-ABM are discussed for obtaining ecological validity.


Attentional Bias , Virtual Reality , Humans , Anxiety , Anxiety Disorders , Health Status
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