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1.
J Exp Bot ; 75(13): 3862-3876, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38571323

RESUMO

Rapid elongation of coleoptiles from rice seeds to reach the water surface enables plants to survive submergence stress and therefore plays a crucial role in allowing direct seeding in rice cultivation. Gibberellin (GA) positively influences growth in rice, but the molecular mechanisms underlying its regulation of coleoptile elongation under submerged conditions remain unclear. In this study, we performed a weighted gene co-expression network analysis to conduct a preliminarily examination of the mechanisms. Four key modules were identified with high correlations to the GA regulation of submergence tolerance. The genes within these modules were mainly involved in the Golgi apparatus and carbohydrate metabolic pathways, suggesting their involvement in enhancing submergence tolerance. Further analysis of natural variation revealed that the specific hub genes Os03g0337900, Os03g0355600, and Os07g0638400 exhibited strong correlations with subspecies divergence of the coleoptile elongation phenotype. Consistent with this analysis, mutation of Os07g0638400 resulted in a lower germination potential and a stronger inhibition of coleoptile elongation under submerged conditions. The hub genes identified in this study provide new insights into the molecular mechanisms underlying GA-dependent tolerance to submergence stress in rice, and a potential basis for future modification of rice germplasm to allow for direct seeding.


Assuntos
Cotilédone , Germinação , Giberelinas , Oryza , Sementes , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Giberelinas/metabolismo , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , Cotilédone/fisiologia , Germinação/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas , Reguladores de Crescimento de Plantas/metabolismo
2.
J Fluoresc ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300482

RESUMO

Diabetic mellitus management extends beyond blood glucose monitoring to the essential task of mitigating the overexpression of reactive oxygen species (ROS), particularly vital for cellular repair, especially within the nervous system. Herein, antioxidant carbon dots (Arg-CDs) were designed and prepared using anhydrous citric acid, L-arginine, and ethylenediamine as sources through a hydrothermal method. Arg-CDs exhibited excellent scavenging ability to 2,2-Diphenyl-1-picrylhydrazyl (DPPH∙), and fluorescence response to hydroxyl radicals (∙OH), a characteristic representative of reactive oxygen species (ROS). Assisted by glucose oxidase and Fe2+, Arg-CDs showed a sensitive and selective response to glucose. The quenching mechanism of Arg-CDs by formed ∙OH was based on the static quenching effect (SQE). The analytical performance of this method for glucose detection encompassed a wide linear range (0.3-15 µM), a low practical limit of detection (0.1 µM) and practical applicability for blood glucose monitoring. In an in vitro model employing glial cells (BV2 cells), it was observed that high glucose medium led to notable cellular damage ascribed to the excessive ROS production from hyperglycemia. The diminished and apoptotic glial cells were gradually recovered by adding increased contents of Arg-CDs. This work illustrates a promising area that designs effective carbon dots with antioxidant capacity for the dual applications of detection and cell repairing based on the utilization of antioxidant activity.

3.
BMC Cardiovasc Disord ; 24(1): 549, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39395961

RESUMO

BACKGROUND: The prognostic significance of obstructive sleep apnea (OSA) in patients with unstable angina (UA) based on remnant cholesterol (RC) or triglyceride (TG) levels remains unclear. This study aims to evaluate the effects of the interaction between RC, TG, and OSA on cardiovascular outcomes in UA patients. METHODS: In this prospective cohort study, OSA was diagnosed when apnea-hypopnea index of ≥ 15 events/h. Patients with high RC (HRC, n = 370) or high TG (HTG, n = 362) included RC or TG in the highest tertile, and those in the middle and lowest tertiles were defined as normal RC (NRC, n = 736) or normal TG (NTG, n = 744). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), including cardiovascular death, myocardial infarction, ischemia stroke, ischemia-driven revascularization, or hospitalization for UA. RESULTS: A total of 1,106 eligible UA patients were enrolled, among which 560 (50.6%) had OSA. RC and TG levels were increased in OSA patients, but there was no difference in the prevalence of OSA between the NRC and HRC or NTG and HTG groups. During a median follow-up of 1.9 (1.1, 3.0) years, OSA was associated with an increased risk of MACCE occurrence compared to non-OSA in UA patients with HRC (adjusted HR 2.06; 95% CI 1.20-3.51, P = 0.008), but not in those with NRC (adjusted HR 1.21; 95% CI 0.84-1.75, P = 0.297). The incremental risk in HRC was attributable to higher rates of hospitalization for UA and ischemia-driven revascularization. Results for HTG and NTG were similar. CONCLUSION: OSA was associated with a worse prognosis in UA patients with HRC or HTG, emphasizing the necessity of identifying OSA presence in this population. TRIAL REGISTRATION: Clinicaltrials.gov; No: NCT03362385.


Assuntos
Angina Instável , Biomarcadores , Colesterol , Apneia Obstrutiva do Sono , Triglicerídeos , Humanos , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/mortalidade , Apneia Obstrutiva do Sono/complicações , Feminino , Angina Instável/sangue , Angina Instável/mortalidade , Angina Instável/diagnóstico , Angina Instável/epidemiologia , Masculino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Triglicerídeos/sangue , Colesterol/sangue , Prognóstico , Biomarcadores/sangue , Fatores de Risco , Medição de Risco , Fatores de Tempo , Prevalência
4.
Angew Chem Int Ed Engl ; 63(42): e202412283, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39011879

RESUMO

Circularly polarized electroluminescence (CPEL) is highly promising in realm of 3D display and optical data storage. However, designing a groundbreaking chiral material with high comprehensive CPEL performance remains a formidable challenge. In this work, a pair of chiral polymers with self-assembled behavior is designed by integrating a chiral BN-moiety into polyfluorene backbone, named R-PBN and S-PBN, respectively. The chiral polymers show narrowband emission centered at 490 nm with full-width half maximum (FWHM) of 29 nm and high photoluminescence quantum yield (PLQY) of 79 %. After thermal annealing treatment, the chiral polymers undergo self-assembly, exhibiting amplified circularly polarized luminescence (CPL) with asymmetry factor (|glum|) of up to 0.11. Moreover, the solution-processed nondoped CP-OLEDs based on the chiral polymers as emitting layers exhibit maximum external quantum efficiency (EQEmax) of 9.8 %, intense CPEL activities with |gEL| of up to 0.07, and small FWHM of 36 nm, simultaneously. This represents the first case of self-assembled chiral polymers that combines high EQE, large gEL value and narrowband emission.

5.
Angew Chem Int Ed Engl ; 63(18): e202401835, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38380835

RESUMO

The intrinsic helical π-conjugated skeleton makes helicenes highly promising for circularly polarized electroluminescence (CPEL). Generally, carbon helicenes undergo low external quantum efficiency (EQE), while the incorporation of a multi-resonance thermally activated delayed fluorescence (MR-TADF) BN structure has led to an improvement. However, the reported B,N-embedded helicenes all show low electroluminescence dissymmetry factors (gEL), typically around 1×10-3. Therefore, the development of B,N-embedded helicenes with both a high EQE and gEL value is crucial for achieving highly efficient CPEL. Herein, a facile approach to synthesize B,N-embedded hetero[9]helicenes, BN[9]H, is presented. BN[9]H shows a bright photoluminescence with a maximum at 578 nm with a high luminescence dissymmetry factor (|glum|) up to 5.8×10-3, attributed to its inherited MR-TADF property and intrinsic helical skeleton. Furthermore, circularly polarized OLED devices incorporating BN[9]H as an emitter show a maximum EQE of 35.5 %, a small full width at half-maximum of 48 nm, and, more importantly, a high |gEL| value of 6.2×10-3. The Q-factor (|EQE×gEL|) of CP-OLEDs is determined to be 2.2×10-3, which is the highest among helicene analogues. This work provides a new approach for the synthesis of higher helicenes and paves a new way for the construction of highly efficient CPEL materials.

6.
Angew Chem Int Ed Engl ; : e202416863, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39387346

RESUMO

Stimuli-responsive circularly polarized luminescence (CPL) materials have been attaching wide attention in the field of optical information storage and encryption, while still facing the challenge of the realization of high luminescence dissymmetry factors (glum). This work presents a pair of stimuli-responsive chiral co-assemblies P7R3 and P7S3 by combining polymer PFIQ containing iso-quinoline units with chiral inducers. The obtained chiral co-assemblies can reversibly undergo significant modification in CPL behavior under trifluoroacetic acid (TFA) fumigation and annealing treatment, with the |glum| values exhibiting a reversible shift between 0.2 and 0.3. Moreover, the chiral co-assemblies before TFA fumigating can effectively induce achiral emitters to generate intense full-color CPL signals through CPL energy transfer (CPL-ET), with the corresponding |glum| values larger than 0.2. Moreover, information encryption and decryption as well as a multi-level logic gates application are achieved by leveraging the reversible stimuli-responsive CPL activity of the chiral co-assembly. This work provides a new perspective for the construction of stimuli-responsive chiral luminescent materials with large |glum| values and the activation of CPL behavior in achiral emitters.

7.
Angew Chem Int Ed Engl ; : e202417458, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379791

RESUMO

Aiming at the fabrication of circularly polarized organic light-emitting diodes (CP-OLEDs) with high dissymmetry factors (gEL) and color purity through the employment of novel chiral source, topologically chiral [2]catenanes were first utilized as the key chiral skeleton to construct novel multi-resonance thermally activated delayed fluorescence (MR-TADF) emitters. Impressively, the efficient chirality induction and unique switchable feature of topologically chiral [2]catenane not only lead to a high |gPL| value up to 1.6 × 10-2 but also facilitate in situ dynamic switching of the full-width at half-maximum (FWHM) and circularly polarized luminescence (CPL). Furthermore, the solution-processed CP-OLEDs based on the resultant topologically chiral emitters exhibit reveal narrow FWHM of 36 nm, maximum external quantum efficiency of 17.6%, and CPEL with |gEL| of 2.1 × 10-3. This study demonstrates the successful construction of the first CP-MR-TADF emitters based on topological chirality with the highest |gPL| among the reported CP-MR-TADF emitters and excellent device performance to the best of our knowledge. Moreover, it endowed the MR-TADF emitter with distinctive switchable CPL performances, thus providing a novel design strategy as well as a promising platform for developing intelligent CP-OLEDs.

8.
J Transl Med ; 21(1): 91, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750951

RESUMO

BACKGROUND: Length of stay (LOS) is an important metric for evaluating the management of inpatients. This study aimed to explore the factors impacting the LOS of inpatients with type-2 diabetes mellitus (T2DM) and develop a predictive model for the early identification of inpatients with prolonged LOS. METHODS: A 13-year multicenter retrospective study was conducted on 83,776 patients with T2DM to develop and validate a clinical predictive tool for prolonged LOS. Least absolute shrinkage and selection operator regression model and multivariable logistic regression analysis were adopted to build the risk model for prolonged LOS, and a nomogram was taken to visualize the model. Furthermore, receiver operating characteristic curves, calibration curves, and decision curve analysis and clinical impact curves were used to respectively validate the discrimination, calibration, and clinical applicability of the model. RESULTS: The result showed that age, cerebral infarction, antihypertensive drug use, antiplatelet and anticoagulant use, past surgical history, past medical history, smoking, drinking, and neutrophil percentage-to-albumin ratio were closely related to the prolonged LOS. Area under the curve values of the nomogram in the training, internal validation, external validation set 1, and external validation set 2 were 0.803 (95% CI [confidence interval] 0.799-0.808), 0.794 (95% CI 0.788-0.800), 0.754 (95% CI 0.739-0.770), and 0.743 (95% CI 0.722-0.763), respectively. The calibration curves indicated that the nomogram had a strong calibration. Besides, decision curve analysis, and clinical impact curves exhibited that the nomogram had favorable clinical practical value. Besides, an online interface ( https://cytjt007.shinyapps.io/prolonged_los/ ) was developed to provide convenient access for users. CONCLUSION: In sum, the proposed model could predict the possible prolonged LOS of inpatients with T2DM and help the clinicians to improve efficiency in bed management.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Estudos Retrospectivos , Estudos de Casos e Controles , Fatores de Risco , Albuminas
9.
Glob Chang Biol ; 29(5): 1407-1419, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36397251

RESUMO

Organisms have been shifting their timing of life history events (phenology) in response to changes in the emergence of resources induced by climate change. Yet understanding these patterns at large scales and across long time series is often challenging. Here we used the US weather surveillance radar network to collect data on the timing of communal swallow and martin roosts and evaluate the scale of phenological shifts and its potential association with temperature. The discrete morning departures of these aggregated aerial insectivores from ground-based roosting locations are detected by radars around sunrise. For the first time, we applied a machine learning algorithm to automatically detect and track these large-scale behaviors. We used 21 years of data from 12 weather surveillance radar stations in the Great Lakes region to quantify the phenology in roosting behavior of aerial insectivores at three spatial levels: local roost cluster, radar station, and across the Great Lakes region. We show that their peak roosting activity timing has advanced by 2.26 days per decade at the regional scale. Similar signals of advancement were found at the station scale, but not at the local roost cluster scale. Air temperature trends in the Great Lakes region during the active roosting period were predictive of later stages of roosting phenology trends (75% and 90% passage dates). Our study represents one of the longest-term broad-scale phenology examinations of avian aerial insectivore species responding to environmental change and provides a stepping stone for examining potential phenological mismatches across trophic levels at broad spatial scales.


Assuntos
Radar , Tempo (Meteorologia) , Estações do Ano , Temperatura , Mudança Climática , Great Lakes Region
10.
Angew Chem Int Ed Engl ; 62(4): e202215367, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36428269

RESUMO

Chiral nanographenes with both high fluorescence quantum yields (ΦF ) and large dissymmetry factors (glum ) are essential to the development of circularly polarized luminescence (CPL) materials. However, most studies have been focused on the improvement of glum , whereas how to design highly emissive chiral nanographenes is still unclear. In this work, we propose a new design strategy to achieve chiral nanographenes with high ΦF by helical π-extension of strongly luminescent chromophores while maintaining the frontier molecular orbital (FMO) distribution pattern. Chiral nanographene with perylene as the core and two dibenzo[6]helicene fragments as the wings has been synthesized, which exhibits a record high ΦF of 93 % among the reported chiral nanographenes and excellent CPL brightness (BCPL ) of 32 M-1 cm-1 .

11.
Mol Plant Microbe Interact ; 35(10): 893-905, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35762679

RESUMO

Legumes in the inverted repeat-lacking clade (IRLC) each produce a unique set of nodule-specific cysteine-rich (NCR) peptides, which act in concert to determine the terminal differentiation of nitrogen-fixing bacteroid. IRLC legumes differ greatly in their numbers of NCR and sequence diversity. This raises the significant question how bacteroid differentiation is collectively controlled by the specific NCR repertoire of an IRLC legume. Astragalus sinicus is an IRLC legume that forms indeterminate nodules with its microsymbiont Mesorhizobium huakuii 7653R. Here, we performed transcriptome analysis of root and nodule samples at 3, 7, 14, 28 days postinoculation with M. huakuii 7653R and its isogenic ∆bacA mutant. BacA is a broad-specificity peptide transporter required for the host-derived NCRs to target rhizobial cells. A total of 167 NCRs were identified in the RNA transcripts. Comparative sequence and electrochemical analysis revealed that A. sinicus NCRs (AsNCRs) are dominated by a unique cationic group (termed subgroup C), whose mature portion is relatively long (>60 amino acids) and phylogenetically distinct and possessing six highly conserved cysteine residues. Subsequent functional characterization showed that a 7653R variant harboring AsNCR083 (a representative of subgroup C AsNCR) displayed significant growth inhibition in laboratory media and formed ineffective white nodules on A. sinicus with irregular symbiosomes. Finally, bacterial two-hybrid analysis led to the identification of GroEL1 and GroEL3 as the molecular targets of AsNCR067 and AsNCR076. Together, our data contribute to a systematic understanding of the NCR repertoire associated with the A. sinicus and M. huakuii symbiosis. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Cisteína , Fabaceae , Cisteína/química , Cisteína/genética , Cisteína/metabolismo , Fabaceae/microbiologia , Nitrogênio/metabolismo , Fixação de Nitrogênio/genética , Peptídeos/metabolismo , RNA/metabolismo , Nódulos Radiculares de Plantas/microbiologia , Simbiose/genética , Transcriptoma/genética
12.
J Magn Reson Imaging ; 55(4): 1095-1106, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34480787

RESUMO

BACKGROUND: Noninvasive evaluation of the status of cerebral arteriole perfusion remains a practical challenge in murine stroke models, because conventional magnetic resonance imaging (MRI) is no longer capable of capturing these very small vessels. PURPOSE: To investigate the feasibility of ultrasmall superparamagnetic iron oxide particles (USPIO)-based susceptibility weighted imaging (SWI)-MRI (USPIO-SWI) and T2* map-MRI (USPIO-T2* map) for monitoring angiographic perfusion in stroke rats. STUDY TYPE: A preclinical randomized controlled trial. ANIMAL MODEL: Normal rats (N = 9), embolic middle cerebral artery occlusion (eMCAO) rats (N = 66). FIELD STRENGTH/SEQUENCE: 7 T; T2* map (multigradient echo), SWI (3D gradient echo). ASSESSMENT: Experiment 1: To develop a method for angiographic reperfusion evaluation with USPIO-SWI. Normal rats were used to optimize the USPIO dosage (5.6, 16.8, and 56 mg/kg ferumoxytol) as well as scan time points for cerebral arterioles. Contrast-to-noise ratio (CNR) was measured. Stroke rats were further used and the number of visual cortical vessels were counted. Experiment 2: To examine whether fingolimod (lymphocytes inhibitor) enhances the action of tissue plasminogen activator (tPA) in eMCAO rats on cerebral angiographic reperfusion. STATISTICAL TESTS: Mann-Whitney test and two way-ANOVA were used. P < 0.05 was considered statistically significant. RESULTS: CNR values of cerebral cortical penetrating arteries in normal rats were significantly increased to 4.4 ± 0.5 (5.6 mg/kg), 6.1 ± 0.5 (16.8 mg/kg), and 3.4 ± 0.9 (56 mg/kg) after USPIO injection. The number of visual cortical vessels on USPIO-SWI images in ischemic regions was significantly less than in control regions (5 ± 2 vs. 56 ± 20) of eMCAO rats. Compared with eMCAO rats who received tPA only, eMCAO rats who received the combination of fingolimod and tPA exhibited significantly higher proportion of complete angiographic reperfusion (69% vs. 17%). DATA CONCLUSION: This study supports the feasibility of angiographic perfusion evaluation with USPIO-SWI in stroke rats. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 1.


Assuntos
Embolia , Nanopartículas de Magnetita , Acidente Vascular Cerebral , Animais , Camundongos , Ratos , Meios de Contraste , Dextranos , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Reperfusão , Ativador de Plasminogênio Tecidual/uso terapêutico
13.
BMC Pulm Med ; 22(1): 4, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34991543

RESUMO

OBJECTIVE: To differentiate nontuberculous mycobacteria (NTM) pulmonary diseases from pulmonary tuberculosis (PTB) by analyzing the CT radiomics features of their cavity. METHODS: 73 patients of NTM pulmonary diseases and 69 patients of PTB with the cavity in Shandong Province Chest Hospital and Qilu Hospital of Shandong University were retrospectively analyzed. 20 patients of NTM pulmonary diseases and 20 patients of PTB with the cavity in Jinan Infectious Disease Hospitall were collected for external validation of the model. 379 cavities as the region of interesting (ROI) from chest CT images were performed by 2 experienced radiologists. 80% of cavities were allocated to the training set and 20% to the validation set using a random number generated by a computer. 1409 radiomics features extracted from the Huiying Radcloud platform were used to analyze the two kinds of diseases' CT cavity characteristics. Feature selection was performed using analysis of variance (ANOVA) and least absolute shrinkage and selection operator (LASSO) methods, and six supervised learning classifiers (KNN, SVM, XGBoost, RF, LR, and DT models) were used to analyze the features. RESULTS: 29 optimal features were selected by the variance threshold method, K best method, and Lasso algorithm.and the ROC curve values are obtained. In the training set, the AUC values of the six models were all greater than 0.97, 95% CI were 0.95-1.00, the sensitivity was greater than 0.92, and the specificity was greater than 0.92. In the validation set, the AUC values of the six models were all greater than 0.84, 95% CI were 0.76-1.00, the sensitivity was greater than 0.79, and the specificity was greater than 0.79. In the external validation set, The AUC values of the six models were all greater than 0.84, LR classifier has the highest precision, recall and F1-score, which were 0.92, 0.94, 0.93. CONCLUSION: The radiomics features extracted from cavity on CT images can provide effective proof in distinguishing the NTM pulmonary disease from PTB, and the radiomics analysis shows a more accurate diagnosis than the radiologists. Among the six classifiers, LR classifier has the best performance in identifying two diseases.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Infecções por Mycobacterium não Tuberculosas/diagnóstico por imagem , Tomógrafos Computadorizados , Tuberculose Pulmonar/diagnóstico por imagem , China , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Micobactérias não Tuberculosas , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(6): 1118-1126, 2022 Nov.
Artigo em Zh | MEDLINE | ID: mdl-36443062

RESUMO

N 6-methyladenosine (m 6A) is the most prevalent post-transcriptional RNA modification in eukaryotic cells. m 6A methyltransferase complexes and demethylases are involved in the dynamic and reversible regulation of m 6A modification, while m 6A binding proteins could specifically identify m 6A modification and regulate RNA metabolism, including splicing, translocation, stability, and translation. m 6A is found to play a vital role in all the fundamental biological processes, including the regulation of the immune system, from normal development to diseases. The normal development and functioning of the immune system rely on the precise regulation of the relevant gene expression, and m 6A modification is crucial to the regulation. Herein, we reviewed the concept, the functions, and the mechanism of m 6A modification, concentrating on its role in immune system function modulation. Furthermore, we highlighted present obstacles and future research directions in the field, intending to provide a theoretical foundation and reference for future study on how m 6A modification is involved in immune regulation.


Assuntos
Imunidade , RNA , Citoplasma , Imunidade/genética
15.
Mol Plant Microbe Interact ; 34(5): 547-559, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33596109

RESUMO

Rhizobia are rod-shaped bacteria that form nitrogen-fixing root nodules on leguminous plants; however, they don't carry MreB, a key determinant of rod-like cell shape. Here, we introduced an actin-like mreB homolog from a pseudomonad into Mesorhizobium huakuii 7653R (a microsymbiont of Astragalus sinicus L.) and examined the molecular, cellular, and symbiotic phenotypes of the resultant mutant. Exogenous mreB caused an enlarged cell size and slower growth in laboratory medium. However, the mutant formed small, ineffective nodules on A. sinicus (Nod+ Fix-), and rhizobial cells in the infection zone were unable to differentiate into bacteroids. RNA sequencing analysis also revealed minor effects of mreB on global gene expression in free-living cells but larger effects for cells grown in planta. Differentially expressed nodule-specific genes include cell cycle regulators such as the tubulin-like ftsZ1 and ftsZ2. Unlike the ubiquitous FtsZ1, an FtsZ2 homolog was commonly found in Rhizobium, Sinorhizobium, and Mesorhizobium spp. but not in closely related nonsymbiotic species. Bacterial two-hybrid analysis revealed that MreB interacts with FtsZ1 and FtsZ2, which are targeted by the host-derived nodule-specific cysteine-rich peptides. Significantly, MreB mutation D283A disrupted the protein-protein interactions and restored the aforementioned phenotypic defects caused by MreB in M. huakuii. Together, our data indicate that MreB is detrimental for modern rhizobia and its interaction with FtsZ1 and FtsZ2 causes the symbiotic process to cease at the late stage of bacteroid differentiation. These findings led to a hypothesis that loss of mreB in the common ancestor of members of Rhizobiales and subsequent acquisition of ftsZ2 are critical evolutionary steps leading to legume-rhizobial symbiosis.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Fabaceae , Rhizobium , Proteínas do Citoesqueleto , Mesorhizobium , Fixação de Nitrogênio , Nódulos Radiculares de Plantas , Simbiose
16.
Toxicol Appl Pharmacol ; 431: 115734, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34606778

RESUMO

Emodin is the major anthraquinone component of many important traditional Chinese herbs, such as Rheum palmatum L. and Polygonum multiflorum Thunb. They have been popular health products but recently aroused concerns about their hepatotoxicity, which are believed to be arising from the contained anthraquinones, such as emodin. However, emodin exerts potent hepatoprotective ability, such as anti-fibrotic, anti-oxidative, and anti-inflammatory effects. In this study, 1H NMR based metabolomics approach, complemented with histopathological observation, biochemical measurements, western blotting analysis and real-time quantitative PCR (RT-qPCR), was applied to interpret the paradox of emodin (30 mg/kg, 10 mg/kg BW) using both healthy mice (male, ICR) and chronic CCl4-injured mice (0.1 mL/kg, 0.35% CCl4, 3 times a week for a month). Emodin exerted a weight loss property associated with its lipid-lowing effects, which helped alleviate CCl4-induced steatosis. Emodin effectively ameliorated CCl4-induced oxidative stress and energy metabolism dysfunction in mice liver via regulating glucose, lipid and amino acid metabolism, and inhibited excessive inflammatory response. In healthy mice, emodin only exhibited hepatoxicity on high-dosage by disturbing hepatic anti-oxidant homeostasis, especially GSH and xanthine metabolism. This integrated metabolomics approach identified the bidirectional potential of emodin, which are important for its rational use.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Emodina/farmacologia , Metabolismo Energético/efeitos dos fármacos , Fígado/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Metabolômica , Espectroscopia de Prótons por Ressonância Magnética , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Modelos Animais de Doenças , Emodina/toxicidade , Glutationa/metabolismo , Fígado/metabolismo , Masculino , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Medição de Risco , Transdução de Sinais , Xantina/metabolismo
17.
Reproduction ; 162(6): 437-448, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34605773

RESUMO

The number of children born after assisted reproductive technology (ART) is accumulating rapidly, and the health problems of the children are extensively concerned. This study aims to evaluate whether ART procedures alter behaviours in male offspring. Mouse models were utilized to establish three groups of offspring conceived by natural conception (NC), in vitro fertilization and embryo transfer (IVF-ET), and frozen-thawed embryo transfer (IVF-FET), respectively. A battery of behaviour experiments for evaluating anxiety and depression levels, including the open field test (OFT), elevated plus maze (EPM) test, light/dark transition test (L/DTT), tail suspension test (TST), forced swimming test (FST), and sucrose preference test (SPT) was carried out. Aged (18 months old), but not young (3 months old), male offspring in the IVF-ET and IVF-FET groups, compared with those in the NC group, exhibited increased anxiety and depression-like behaviours. The protein expression levels of three neurotrophins in PFC or hippocampus in aged male offspring from the IVF-ET and IVF-FET groups reduced at different extent, in comparison to NC group. RNA sequencing (RNA-Seq) was performed in the hippocampus of 18 months old offspring to further explore the gene expression profile changes in the three groups. KEGG analyses revealed the coexisted pathways, such as PI3K-Akt signalling pathway, which potentially reflected the similarity and divergence in anxiety and depression between the offspring conceived by IVF-ET and IVF-FET. Our research suggested the adverse effects of advanced age on the psychological health of children born after ART should be highlighted in the future.


Assuntos
Depressão , Fosfatidilinositol 3-Quinases , Animais , Ansiedade/etiologia , Depressão/etiologia , Fertilização in vitro/efeitos adversos , Masculino , Camundongos , Técnicas de Reprodução Assistida/efeitos adversos , Estudos Retrospectivos
18.
Molecules ; 26(23)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34885971

RESUMO

Rhizoma Coptidis (RC) is a widely used traditional Chinese medicine. Although modern research has found that some alkaloids from RC are the pharmacologically active constituents, the differences in their biological effects are not completely clear. This study analyzed the differences in the typical alkaloids in RC at a systematic level and provided comprehensive information on the pharmaceutical mechanisms of the different alkaloids. The ethanol RC extract (RCE) was characterized using HPLC assay. HepG2, 3T3-L1, and RAW264.7 cells were used to detect the cytotoxicity of alkaloids. Transcriptome analyses were performed to elucidate the cellular pathways affected by RCE and alkaloids. HPLC analysis revealed that the typical alkaloids of RCE were berberine, coptisine, and palmatine. Coptisine and berberine displayed a stronger inhibitory effect on cell proliferation than palmatine. The overlapping ratios of differentially expressed genes between RCE and berberine, coptisine, and palmatine were 70.8%, 52.6%, and 42.1%, respectively. Pathway clustering analysis indicated that berberine and coptisine possessed a certain similarity to RCE, and both compounds affected the cell cycle pathway; moreover, some pathways were uniquely enriched by berberine or coptisine. Berberine and coptisine had different regulatory effects on genes involved in lipid metabolism. These results provide comprehensive information on the pharmaceutical mechanisms of the different RC alkaloids and insights into their better combinatory use for the treatment of diseases.


Assuntos
Alcaloides de Berberina/farmacologia , Berberina/análogos & derivados , Coptis chinensis/química , Coptis/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Rizoma/química , Células 3T3-L1 , Animais , Berberina/análise , Berberina/farmacologia , Alcaloides de Berberina/análise , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Camundongos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
19.
Angew Chem Int Ed Engl ; 60(44): 23619-23624, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34490710

RESUMO

A strategy of chiral donor-acceptor copolymerization is proposed to develop chiral nonconjugated polymers with thermally activated delayed fluorescence (TADF). Based on this strategy, two pairs of chiral polymers (R,R)-/(S,S)-pTpAcDPS and (R,R)-/(S,S)-pTpAcBP were synthesized. The alternating copolymerization of the chiral donors and acceptors could effectively separate the frontier molecular orbitals, which made the polymers show small ΔEST of 0.01-0.03 eV and efficient TADF properties. Moreover, the polymers also showed the quantum yield of up to 92 % and the circularly polarized luminescence. The solution-processed circularly polarized organic light-emitting diodes showed circularly polarized electroluminescence signals with high external quantum efficiencies of up to 22.1 % and maximum luminance of up to 34350 cd m-2 . This is the first report of CP-OLEDs based on chiral TADF polymer, which provides a useful and valuable guidance for the development of high-efficiency CPEL polymers.

20.
Zhonghua Nan Ke Xue ; 26(5): 392-398, 2020 May.
Artigo em Zh | MEDLINE | ID: mdl-33354946

RESUMO

OBJECTIVE: To investigate the role of a long noncoding RNA (lncRNA) transcribed from the RHNO1 gene we newly identified in DNA double-strand break (DSB) repair. METHODS: The transcription and translation of the RHNO1 gene were validated by Western blot, real-time PCR and liquid chromatography-tandem mass spectrometry (LC-MS/MS) based on the overexpressed RHNO1 plasmid. The transcription level of RHNO1 in the mouse tissue was detected by real-time PCR and its expression in the spermatogenic cycle determined by in situ hybridization. The role of RHNO1 in the DNA DSB repair was further verified using the DSB model established by exposing the germ cells to ultraviolent radiation. RESULTS: The full-length RHNO1 gene could be transcribed as a novel lncRNA in vitro, highly expressed in the mouse testis tissue, and mainly located in spermatocytes and round spermatids. RHNO1 was involved in DNA DSB repair in the spermatogenic cells. CONCLUSIONS: We identified a novel lncRNA, RHNO1, which is highly expressed in the mouse testis and participates in DNA damage repair in the germ cell line.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , RNA Longo não Codificante/genética , Testículo , Animais , Cromatografia Líquida , Masculino , Camundongos , Espectrometria de Massas em Tandem
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