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1.
Plant Biotechnol J ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39031643

RESUMO

Dual base editors (DBEs) enable simultaneous A-to-G and C-to-T conversions, expanding mutation types. However, low editing efficiency and narrow targeting range limit the widespread use of DBEs in plants. The single-strand DNA binding domain of RAD51 DBD can be fused to base editors to improve their editing efficiency. However, it remains unclear how the DBD affects dual base editing performance in plants. In this study, we generated a series of novel plant DBE-SpGn tools consisting of nine constructs using the high-activity cytidine deaminase evoFERNY, adenosine deaminase TadA8e and DBD in various fusion modes with the PAM-flexible Streptococcus pyogenes Cas9 (SpCas9) nickase variant SpGn (with NG-PAM). By analysing their editing performance on 48 targets in rice, we found that DBE-SpGn constructs containing a single DBD and deaminases located at the N-terminus of SpGn exhibited the highest editing efficiencies. Meanwhile, constructs with deaminases located at the C-terminus and/or multiple DBDs failed to function normally and exhibited inhibited editing activity. We identified three particularly high-efficiency dual base editors (C-A-SpGn, C-A-D-SpGn and A-C-D-SpGn), named PhieDBEs (Plant high-efficiency dual base editors), capable of producing efficient dual base conversions within a narrow editing window (M5 ~ M9, M = A/C). The editing efficiency of C-A-D-SpGn was as high as 95.2% at certain target sites, with frequencies of simultaneous C-to-T and A-to-G conversions as high as 81.0%. In summary, PhieDBEs (especially C-A-D-SpGn) can produce diverse mutants and may prove useful in a wide variety of applications, including plant functional genomics, precise mutagenesis, directed evolution and crop genetic improvement, among others.

2.
Front Endocrinol (Lausanne) ; 15: 1429261, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39027482

RESUMO

Objectives: To evaluate the efficacy and safety of non-steroid mineralocorticoid receptor antagonists (ns-MRAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2is) in patients with diabetic kidney disease (DKD). Methods: Systematic literature searches were performed using PubMed, Embase and Web of Science encompassing inception until January 20, 2024. Randomized control trials (RCTs) comparing ns-MRAs and SGLT2is in DKD were selected. The efficacy outcomes of interest included kidney-specific composite outcome, cardiovascular (CV)-specific composite outcome, end-stage kidney disease (ESKD), and overall mortality. We also investigated safety outcomes, including acute kidney injury (AKI) and hyperkalemia. Results: A total of 10 randomized clinical trials with 35,786 patients applying various treatments were included. SGLT2is (SUCRA 99.84%) have potential superiority in kidney protection. SGLT2is (RR 1.41, 95%CI 1.26 to 1.57) and ns-MRAs (RR 1.17, 95% CI 1.08 to 1.27) were associated with significantly lower kidney-specific composite outcome than the placebo. Regarding the reduction in CV-specific composite outcome and ESKD, SGLT2is (SUCRA 91.61%; 91.38%) have potential superiority in playing cardiorenal protection. Concerning the CV-specific composite outcome (RR 1.27, 95%CI 1.09 to 1.43) and ESKD (RR 1.43, 95%CI 1.20 to 1.72), SGLT2is significantly reduced the risks compared to placebo. Regarding the reduction in overall mortality, SGLT2is (SUCRA 83.03%) have potential superiority in postponing mortality. Concerning the overall mortality, SGLT2is have comparable effects (RR 1.27, 95%CI 1.09 to 1.43) with placebo to reduce the risk of overall mortality compared to placebo. For AKI reduction, ns-MRAs (SUCRA 63.58%) have potential superiority. SGLT2is have comparable effects (RR 1.24, 95%CI 1.05 to 1.46) with placebo to reduce the risk of AKI. For hyperkalemia reduction, SGLT2is (SUCRA 93.12%) have potential superiority. SGLT2is have comparable effects (RR 1.24, 95%CI 1.05 to 1.46) with placebo to reduce the risk of AKI. Concerning hyperkalemia reduction, nsMRAs (RR 1.24 95%CI 0.39 to 3.72) and SGLT2is (RR 1.01 95%CI 0.40 to 3.02) did not show significant benefit compared to placebo. Conclusion: Concerning the efficacy and safety outcomes, SGLT2is may be recommended as a treatment regimen for maximizing kidney and cardiovascular protection, with a minimal risk of hyperkalemia in DKD. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023458613.


Assuntos
Nefropatias Diabéticas , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Nefropatias Diabéticas/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico
3.
Bioinform Biol Insights ; 18: 11779322241261427, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39081667

RESUMO

The secreted phospholipase A2 (sPLA2) isoform, sPLA2-IIA, has been implicated in a variety of diseases and conditions, including bacteremia, cardiovascular disease, COVID-19, sepsis, adult respiratory distress syndrome, and certain cancers. Given its significant role in these conditions, understanding the regulatory mechanisms impacting its levels is crucial. Genome-wide association studies (GWAS) have identified several single nucleotide polymorphisms (SNPs), including rs11573156, that are associated with circulating levels of sPLA2-IIA. The work in the manuscript leveraged 4 publicly available datasets to investigate the mechanism by which rs11573156 influences sPLA2-IIA levels via bioinformatics and modeling analysis. Through genotype-tissue expression (GTEx), 234 expression quantitative trait loci (eQTLs) were identified for the gene that encodes for sPLA2-IIA, PLA2G2A. SNP2TFBS was used to ascertain the binding affinities between transcription factors (TFs) to both the reference and alternative alleles of identified eQTL SNPs. Subsequently, candidate TF-SNP interactions were cross-referenced with the ChIP-seq results in matched tissues from ENCODE. SP1-rs11573156 emerged as the significant TF-SNP pair in the liver. Further analysis revealed that the upregulation of PLA2G2A transcript levels through the rs11573156 variant was likely affected by tissue SP1 protein levels. Using an ordinary differential equation based on Michaelis-Menten kinetic assumptions, we modeled the dependence of PLA2G2A transcription on SP1 protein levels, incorporating the SNP influence. Collectively, our analysis strongly suggests that the difference in the binding dynamics of SP1 to different rs11573156 alleles may underlie the allele-specific PLA2G2A expression in different tissues, a mechanistic model that awaits future direct experimental validation. This mechanism likely contributes to the variation in circulating sPLA2-IIA protein levels in the human population, with implications for a wide range of human diseases.

4.
Methods Mol Biol ; 2811: 123-135, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39037654

RESUMO

High-throughput transcriptome RNA sequencing is a powerful tool for understanding dynamic biological processes. Here, we present a computational framework, implemented in an R package QDSWorkflow, to characterize heterogeneous cellular dormancy depth using RNA-sequencing data from bulk samples and single cells.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Software , Análise de Sequência de RNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Biologia Computacional/métodos , Transcriptoma , Perfilação da Expressão Gênica/métodos , Humanos , Análise de Célula Única/métodos
5.
J Thorac Dis ; 16(6): 3740-3752, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38983149

RESUMO

Background: Due to the widespread use of computed tomography (CT) screening and advances in diagnostic techniques, an increasing number of patients with multiple pulmonary nodules are being detected and pathologically diagnosed as synchronous multiple primary lung cancers (sMPLC). It has become a new challenge to treat multiple pulmonary nodules and obtain a favorable prognosis while minimizing the perioperative risk for patients. The purpose of this study was to summarize the preliminary experience with a hybrid surgery combining pulmonary resection and ablation for the treatment of sMPLC and to discuss the feasibility of this novel procedure with a literature review. Methods: This is a retrospective non-randomized controlled study. From January 1, 2022 to July 1, 2023, four patients underwent hybrid surgery combining thoracoscopic pulmonary resection and percutaneous pulmonary ablation for multiple pulmonary nodules. Patients were followed up at 3, 6 and 12 months postoperatively and the last follow-up was on November 30, 2023. Clinical characteristics, perioperative outcomes, pulmonary function recovery and oncologic prognosis were recorded. Meanwhile we did a literature review of studies on hybridized pulmonary surgery for the treatment of multiple pulmonary nodules. Results: All the four patients were female, aged 52 to 70 years, and had no severe cardiopulmonary dysfunction on preoperative examination. Hybrid surgery of simultaneous pulmonary resection and ablation were performed in these patients to treat 2 to 4 pulmonary nodules, assisted by intraoperative real-time guide of C-arm X-ray machine. The operation time was from 155 to 240 minutes, and intraoperative blood loss was from 50 to 200 mL. Postoperative hospital stay was 2 to 7 days, thoracic drainage duration was 2 to 6 days, and pleural drainage volume was 300-1,770 mL. One patient presented with a bronchopleural fistula due to pulmonary ablation; the fistula was identified and sutured during thoracoscopic surgery and the patient recovered well. No postoperative 90-day complications occurred. After 3 months postoperatively, performance status scores for these patients recovered to 80 to 100. No tumor recurrence or metastasis was detected during the follow-up period. Conclusions: Hybrid procedures combining minimally invasive pulmonary resection with ablation are particularly suitable for the simultaneous treatment of sMPLC. Patients had less loss of pulmonary function, fewer perioperative complications, and favorable oncologic prognosis. Hybrid surgery is expected to be a better treatment option for patients with sMPLC.

6.
Adv Mater ; : e2402221, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037020

RESUMO

Stretchable electronics have demonstrated excellent potential in wearable healthcare and conformal integration. Achieving the scalable fabrication of stretchable devices with high functional density is the cornerstone to enable the practical applications of stretchable electronics. Here, a comprehensive methodology for realizing large-scale, 3D, and stretchable circuits (3D-LSC) is reported. The soft copper-clad laminate (S-CCL) based on the "cast and cure" process facilitates patterning the planar interconnects with the scale beyond 1 m. With the ability to form through, buried and blind VIAs in the multilayer stack of S-CCLs, high functional density can be achieved by further creating vertical interconnects in stacked S-CCLs. The application of temporary bonding substrate effectively minimizes the misalignments caused by residual strain and thermal strain. 3D-LSC enables the batch production of stretchable skin patches based on five-layer stretchable circuits, which can serve as a miniaturized system for physiological signals monitoring with wireless power delivery. The fabrications of conformal antenna and stretchable light-emitting diode display further illustrate the potential of 3D-LSC in realizing large-scale stretchable devices.

7.
Chem Biodivers ; : e202401220, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869421

RESUMO

Anoectochilus roxburghii is a well-known and valuable traditional Chinese herb due to various medicinal and functional benefits. In-depth investigation is necessary to discover active ingredients and expand its application. In this study, four new compounds (1-4) along with ten known compounds (5-14) were isolated from the ethanol extract of A.roxburghii. Their structures were elucidated by spectroscopic data interpretation. The isolates were screened for their inhibitory activities on the production of NO in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Among them, compounds 5, 6, 9, 10, 12, 13 and 14 exhibited significant anti-inflammatory activity through inhibiting the release of NO.

8.
J Agric Food Chem ; 72(26): 14684-14700, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38905352

RESUMO

The overuse of antibiotics in animal farming and aquaculture has led to multidrug-resistant methicillin-sensitive Staphylococcus aureus (MR-MSSA) becoming a common pathogen in foodborne diseases. Sophora flavescens Ait. serves as a traditional plant antibacterial agent and functional food ingredient. A total of 30 compounds (1-30) were isolated from the root bark of S. flavescens, consisting of 20 new compounds (1-20). In the biological activity assay, compound 1 demonstrated a remarkable inhibitory effect on MR-MSSA, with an MIC of 2 µg/mL. Furthermore, 1 was found to rapidly eliminate bacteria, inhibit biofilm growth, and exhibit exceptionally low cytotoxicity. Mechanistic studies have revealed that 1 possesses an enhanced membrane-targeting ability, binding to the bacterial cell membrane components phosphatidylglycerol (PG), phosphatidylethanolamine (PE), and cardiolipin (CL). This disruption of bacterial cell membrane integrity increases intracellular reactive oxygen species, protein and DNA leakage, reduced bacterial metabolism, and ultimately bacterial death. In summary, these findings suggest that compound 1 holds promise as a lead compound against MR-MSSA.


Assuntos
Antibacterianos , Permeabilidade da Membrana Celular , Flavonoides , Testes de Sensibilidade Microbiana , Casca de Planta , Extratos Vegetais , Raízes de Plantas , Sophora , Sophora/química , Antibacterianos/farmacologia , Antibacterianos/química , Raízes de Plantas/química , Casca de Planta/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Flavonoides/farmacologia , Flavonoides/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Biofilmes/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sophora flavescens
9.
Front Public Health ; 12: 1335553, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832224

RESUMO

Introduction: This study aims to evaluate the qualifications and identify skill enhancement areas for epidemiological investigators in Centers for Disease Control and Prevention (CDCs) in Guizhou's, informing future training and policy initiatives to strengthen public health responses. Methods: A cross-sectional survey was conducted in August 2022, and an online, self-designed questionnaire on the Epidemiological Dynamic Data Collection platform was administered to evaluate the professional staff in CDCs. The responses were scored and presented using descriptive statistical methods, and the factors influencing the total score were analyzed by one-way ANOVA and linear regression. Results and discussion: A total of 1321 questionnaires were collected, yielding an average score of 14.86±3.49 and a qualification rate of 29.9%. The scoring rate of ability of individual protection and coordination in epidemic control was high (87.25%). Meanwhile, improvements in further training were needed in areas such as data analysis ability (23.67%), knowledge of site disinfection (40.40%), and epidemiological investigation skills (42.50%). No significant difference was observed between the scores of city and county CDCs, (t = 1.071, p =0.284). The effects of gender and age could be disregarded, and the experience in epidemiological work and training (including investigation on COVID-19 cases and contacts), educational background, and professional title partially explained the survey outcome (R Square of the linear regression model was 0.351). The survey indicated the need for additional well-trained epidemiologic investigators in Guizhou. Specified training was effective in improving epidemiologic investigation, and enhancement in data analysis ability and knowledge of field disinfection are recommended in professional staff cultivation.


Assuntos
Competência Profissional , Humanos , Estudos Transversais , China/epidemiologia , Feminino , Masculino , Inquéritos e Questionários , Adulto , Pessoa de Meia-Idade , Competência Profissional/estatística & dados numéricos , COVID-19/prevenção & controle , COVID-19/epidemiologia
10.
11.
Chemistry ; : e202402095, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943462

RESUMO

In the cross-plane single-molecule junctions, the correlation between molecular aromaticity and conductance remained puzzling. Cross-plane break junction (XPBJ) provides new insight into understanding the role of aromaticity and conjugation to molecules on charge transport through the planar molecules. In this work, we investigated the modulation of cross-plane charge transport in pyrene derivatives by hydrogenation and substituents based on the XPBJ method that differs from those used in-plane transport. We measured the electrical conductance of the hydrogenated derivatives of the pyrenes and found that hydrogenation reduces conductance, and the fully hydrogenated molecule has the lowest conductance. Conductance of pyrene derivatives increased after substitution by both electron-donating and electron-withdrawing groups. By calculating, the trend in decreased conductance of hydrogenated pyrene was found to be consistent with the change in aromaticity. Electron-withdrawing substituents reduce the aromaticity of the molecule and narrow the HOMO-LUMO gap, while electron-donating groups increase the aromaticity but also narrow the gap. Our work reveals the potential of fine-tuning the structure of the pyrene molecule to control the cross-plane charge transport through the single-molecule junctions.

12.
Biotechnol Adv ; 74: 108382, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38801866

RESUMO

A plethora of CRISPR effectors, such as Cas3, Cas9, and Cas12a, are commonly employed as gene editing tools. Among these, Cas12 effectors developed based on Class II type V proteins exhibit distinct characteristics compared to Class II type VI and type II effectors, such as their ability to generate non-allelic DNA double-strand breaks, their compact structures, and the presence of a single RuvC-like nuclease domain. Capitalizing on these advantages, Cas12 family proteins have been increasingly explored and utilized in recent years. However, the characteristics and applications of different subfamilies within the type V protein family have not been systematically summarized. In this review, we focus on the characteristics of type V effector (CRISPR/Cas12) proteins and the current methods used to discover new effector proteins. We also summarize recent modifications based on engineering of type V effectors. In addition, we introduce the applications of type V effectors for gene editing in animals and plants, including the development of base editors, tools for regulating gene expression, methods for gene targeting, and biosensors. We emphasize the prospects for development and application of CRISPR/Cas12 effectors with the goal of better utilizing toolkits based on this protein family for crop improvement and enhanced agricultural production.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Genoma de Planta , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Genoma de Planta/genética , Plantas/genética , Plantas/metabolismo , Animais , Plantas Geneticamente Modificadas/genética , Proteínas Associadas a CRISPR/genética , Proteínas Associadas a CRISPR/metabolismo
13.
Sci Bull (Beijing) ; 69(14): 2289-2306, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38821746

RESUMO

Flexible self-powered bioelectronics (FSPBs), incorporating flexible electronic features in biomedical applications, have revolutionized the human-machine interface since they hold the potential to offer natural and seamless human interactions while overcoming the limitations of battery-dependent power sources. Furthermore, as biosensors or actuators, FSPBs can dynamically monitor physiological signals to reveal real-time health abnormalities and provide timely and precise treatments. Therefore, FSPBs are increasingly shaping the landscape of health monitoring and disease treatment, weaving a sophisticated and personalized bond between humans and health management. Here, we examine the recent advanced progress of FSPBs in developing working mechanisms, design strategies, and structural configurations toward personalized health management, emphasizing its role in clinical medical scenarios from biophysical/biochemical sensors for sensing diagnosis to robust/biodegradable actuators for intervention therapy. Future perspectives on the challenges and opportunities in emerging multifunctional FSPBs for the next-generation health management systems are also forecasted.


Assuntos
Técnicas Biossensoriais , Medicina de Precisão , Dispositivos Eletrônicos Vestíveis , Humanos , Medicina de Precisão/métodos , Medicina de Precisão/instrumentação , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Fontes de Energia Elétrica
14.
J Exp Bot ; 75(13): 3762-3777, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38779909

RESUMO

Plants must accurately integrate external environmental signals with their own development to initiate flowering at the appropriate time for reproductive success. Photoperiod and temperature are key external signals that determine flowering time; both are cyclical and periodic, and they are closely related. In this review, we describe photoperiod-sensitive genes that simultaneously respond to temperature signals in rice (Oryza sativa). We introduce the mechanisms by which photoperiod and temperature synergistically regulate heading date and regional adaptation in rice. We also discuss the prospects for designing different combinations of heading date genes and other cold tolerance or thermo-tolerance genes to help rice better adapt to changes in light and temperature via molecular breeding to enhance yield in the future.


Assuntos
Oryza , Fotoperíodo , Temperatura , Oryza/genética , Oryza/fisiologia , Oryza/efeitos da radiação , Flores/fisiologia , Flores/crescimento & desenvolvimento , Flores/genética , Adaptação Fisiológica , Regulação da Expressão Gênica de Plantas
15.
J Drug Target ; 32(7): 785-793, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38721679

RESUMO

Ferroptosis is a novel form of programmed cell death that is iron-dependent and distinct from autophagy, apoptosis, and necroptosis. It is primarily characterised by a decrease in glutathione peroxidase 4 (GPX4) activity, or by the accumulation of lipid peroxidation and reactive oxygen species (ROS). Renal fibrosis is a common pathological change in the progression of various primary and secondary renal diseases to end-stage renal disease and poses a serious threat to human health with high morbidity and mortality. Multiple pathways contribute to the development of renal fibrosis, with ferroptosis playing a crucial role in renal fibrosis pathogenesis due to its involvement in the production of ROS. Ferroptosis is related to several signalling pathways, including System Xc-/GPX4, abnormal iron metabolism and lipid peroxidation. A number of studies have indicated that ferroptosis is closely involved in the process of renal fibrosis caused by various kidney diseases such as glomerulonephritis, renal ischaemia-reperfusion injury, diabetic nephropathy and renal calculus. Identifying the underlying molecular mechanisms that determine cell death would open up new insights to address a therapeutic strategy to renal fibrosis. The review aimed to browse and summarise the known mechanisms of ferroptosis that may be associated with biological reactions of renal fibrosis.


Assuntos
Ferroptose , Fibrose , Ferroptose/fisiologia , Humanos , Animais , Nefropatias/metabolismo , Nefropatias/patologia , Espécies Reativas de Oxigênio/metabolismo , Peroxidação de Lipídeos , Transdução de Sinais , Ferro/metabolismo
16.
Eur J Immunol ; 54(6): e2350721, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38651231

RESUMO

Previous research suggests that group IIA-secreted phospholipase A2 (sPLA2-IIA) plays a role in and predicts lethal COVID-19 disease. The current study reanalyzed a longitudinal proteomic data set to determine the temporal relationship between levels of several members of a family of sPLA2 isoforms and the severity of COVID-19 in 214 ICU patients. The levels of six secreted PLA2 isoforms, sPLA2-IIA, sPLA2-V, sPLA2-X, sPLA2-IB, sPLA2-IIC, and sPLA2-XVI, increased over the first 7 ICU days in those who succumbed to the disease but attenuated over the same time period in survivors. In contrast, a reversed pattern in sPLA2-IID and sPLA2-XIIB levels over 7 days suggests a protective role of these two isoforms. Furthermore, decision tree models demonstrated that sPLA2-IIA outperformed top-ranked cytokines and chemokines as a predictor of patient outcome. Taken together, proteomic analysis revealed temporal sPLA2 patterns that reflect the critical roles of sPLA2 isoforms in severe COVID-19 disease.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/mortalidade , COVID-19/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Fosfolipases A2 Secretórias/sangue , Proteômica/métodos , Índice de Gravidade de Doença , Fosfolipases A2 do Grupo II/sangue , Adulto , Isoformas de Proteínas/sangue , Citocinas/sangue
17.
Biomimetics (Basel) ; 9(4)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38667257

RESUMO

Power ultrasound is widely used in industrial production, medical equipment, aerospace, and other fields. Currently, there are two main types of commonly used power generation devices: piezoelectric ultrasonic transducers and magnetostrictive ultrasonic transducers. However, in certain situations with limited external dimensions, the applications of existing power ultrasound devices are limited. In nature, leaf-cutting ants excite vibrations through their tiny organs. Inspired by the vibratory organs of leaf-cutting ants, a new type of biomimetic ultrasonic vibrator (BUV) comprising a scraper, dentate disc, and fixture system was proposed, fabricated, and tested in this study. The experimental results showed that the BUV could operate in the frequency range of 16.8-19 kHz. Within the working frequency range, the vibration of the BUV was stable and the amplitude of the vibration displacement was greater than 22 µm. The operating frequency band of the BUV was broader than those of the piezoelectric and magnetostrictive ultrasonic transducers. In addition, the BUV can cut soft rubber and pig tissues with sufficient output power and load-carrying capacity. The BUV, as a new type of power ultrasonic excitation device, is expected to be applied in high-power micro operating scenarios, such as minimally invasive surgical instruments.

18.
Plant J ; 118(6): 2108-2123, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38526880

RESUMO

Rice (Oryza sativa L.) is a short-day plant whose heading date is largely determined by photoperiod sensitivity (PS). Many parental lines used in hybrid rice breeding have weak PS, but their F1 progenies have strong PS and exhibit an undesirable transgressive late-maturing phenotype. However, the genetic basis for this phenomenon is unclear. Therefore, effective methods are needed for selecting parents to create F1 hybrid varieties with the desired PS. In this study, we used bulked segregant analysis with F1 Ningyou 1179 (strong PS) and its F2 population, and through analyzing both parental haplotypes and PS data for 918 hybrid rice varieties, to identify the genetic basis of transgressive late maturation which is dependent on dominance complementation effects of Hd1, Ghd7, DTH8, and PRR37 from both parents rather than from a single parental genotype. We designed a molecular marker-assisted selection system to identify the genotypes of Hd1, Ghd7, DTH8, and PRR37 in parental lines to predict PS in F1 plants prior to crossing. Furthermore, we used CRISPR/Cas9 technique to knock out Hd1 in Ning A (sterile line) and Ning B (maintainer line) and obtained an hd1-NY material with weak PS while retaining the elite agronomic traits of NY. Our findings clarified the genetic basis of transgressive late maturation in hybrid rice and developed effective methods for parental selection and gene editing to facilitate the breeding of hybrid varieties with the desired PS for improving their adaptability.


Assuntos
Genes de Plantas , Oryza , Melhoramento Vegetal , Proteínas de Plantas , Alelos , Genótipo , Hibridização Genética , Oryza/genética , Oryza/metabolismo , Fenótipo , Fotoperíodo , Melhoramento Vegetal/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
20.
medRxiv ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38464045

RESUMO

Background: The involvement of the androgen and androgen receptor (AR) pathway in the development of epithelial ovarian cancer is increasingly recognized. However, the specific mechanisms by which anti-androgen agents, such as flutamide, may prevent ovarian cancer and their efficacy remain unknown. We examined the effects of flutamide on the miRNA expression profile found in women at high risk (HR) for ovarian cancer. Methods: Ovarian and tubal tissues, free from ovarian, tubal, peritoneal cancers, and serous tubal intraepithelial carcinoma (STIC), were collected from untreated and flutamide-treated HR women. Low-risk (LR) women served as controls. Transcriptomic miRNA sequencing was performed on these 3 sample cohorts. The miRNAs that showed the most notable differential expression were subjected to functional assays in primary ovarian epithelial cells and ovarian cancer cells. Results: Flutamide treatment demonstrated a normalization effect on diminished miRNA levels in HR tissues compared to LR tissues. Particularly, the miR-449 family was significantly upregulated in HR ovarian tissues following flutamide treatment, reaching levels comparable to those in LR tissues. MiR-449a and miR-449b-5p, members of the miR-449 family, were computationally predicted to target the mRNAs of AR and colony-stimulating factor 1 receptor (CSF1R, also known as c-fms), both of which are known contributors to ovarian cancer progression, with emerging evidence also supporting their roles in ovarian cancer initiation. These findings were experimentally validated in primary ovarian epithelial cells and ovarian cancer cell lines (SKOV3 and Hey): flutamide treatment resulted in elevated levels of miR-449a and miR-449b-5p, and introducing mimics of these miRNAs reduced the mRNA and protein levels of CSF1R and AR. Furthermore, introducing miR-449a and miR-449b-5p mimics showed inhibitory effects on the migration and proliferation of ovarian cancer cells. Conclusion: Flutamide treatment restored the reduced expression of miR-449a and miR-449b-5p in HR tissues, thereby decreasing the expression of CSF1R and AR, functional biomarkers associated with an increased risk of ovarian cancer. In addition to the known direct binding of flutamide to the AR, we found that flutamide also suppresses AR expression via miR-449a and miR-449b-5p upregulation, revealing a novel dual-inhibitory mechanism on the AR pathway. Taken together, our study highlights mechanisms supporting the chemopreventive potential of flutamide in ovarian cancer, particularly in HR patients with reduced miR-449 expression.

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