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1.
BMC Genomics ; 25(1): 319, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549047

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the most common malignant tumors worldwide. Nevertheless, GC still lacks effective diagnosed and monitoring method and treating targets. This study used multi omics data to explore novel biomarkers and immune therapy targets around sphingolipids metabolism genes (SMGs). METHOD: LASSO regression analysis was performed to filter prognostic and differently expression SMGs among TCGA and GTEx data. Risk score model and Kaplan-Meier were built to validate the prognostic SMG signature and prognostic nomogram was further constructed. The biological functions of SMG signature were annotated via multi omics. The heterogeneity landscape of immune microenvironment in GC was explored. qRT-PCR was performed to validate the expression level of SMG signature. Competing endogenous RNA regulatory network was established to explore the molecular regulatory mechanisms. RESULT: 3-SMGs prognostic signature (GLA, LAMC1, TRAF2) and related nomogram were constructed combing several clinical characterizes. The expression difference and diagnostic value were validated by PCR data. Multi omics data reveals 3-SMG signature affects cell cycle and death via several signaling pathways to regulate GC progression. Overexpression of 3-SMG signature influenced various immune cell infiltration in GC microenvironment. RBP-SMGs-miRNA-mRNAs/lncRNAs regulatory network was built to annotate regulatory system. CONCLUSION: Upregulated 3-SMGs signature are excellent predictive diagnosed and prognostic biomarkers, providing a new perspective for future GC immunotherapy.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Prognóstico , Aprendizado de Máquina , Biomarcadores , Esfingolipídeos , Microambiente Tumoral/genética
2.
PLoS One ; 19(2): e0296992, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38349872

RESUMO

The current challenges in Synthetic Aperture Radar (SAR) ship detection tasks revolve around handling significant variations in target sizes and managing high computational expenses, which hinder practical deployment on satellite or mobile airborne platforms. In response to these challenges, this research presents YOLOv7-LDS, a lightweight yet highly accurate SAR ship detection model built upon the YOLOv7 framework. In the core of YOLOv7-LDS's architecture, we introduce a streamlined feature extraction network that strikes a delicate balance between detection precision and computational efficiency. This network is founded on Shufflenetv2 and incorporates Squeeze-and-Excitation (SE) attention mechanisms as its key elements. Additionally, in the Neck section, we introduce the Weighted Efficient Aggregation Network (DCW-ELAN), a fundamental feature extraction module that leverages Coordinate Attention (CA) and Depthwise Convolution (DWConv). This module efficiently aggregates features while preserving the ability to identify small-scale variations, ensuring top-quality feature extraction. Furthermore, we introduce a lightweight Spatial Pyramid Dilated Convolution Cross-Stage Partial Channel (LSPHDCCSPC) module. LSPHDCCSPC is a condensed version of the Spatial Pyramid Pooling Cross-Stage Partial Channel (SPPCSPC) module, incorporating Dilated Convolution (DConv) as a central component for extracting multi-scale information. The experimental results show that YOLOv7-LDS achieves a remarkable Mean Average Precision (mAP) of 99.1% and 95.8% on the SAR Ship Detection Dataset (SSDD) and the NWPU VHR-10 dataset with a parameter count (Params) of 3.4 million, a Giga Floating Point Operations Per Second (GFLOPs) of 6.1 and an Inference Time (IT) of 4.8 milliseconds. YOLOv7-LDS effectively strikes a fine balance between computational cost and detection performance, surpassing many of the current state-of-the-art object detection models. As a result, it offers a more resilient solution for maritime ship monitoring.


Assuntos
Radar , Navios , Humanos
3.
J Diabetes Investig ; 15(4): 491-499, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38108613

RESUMO

AIMS/INTRODUCTION: To explore the association between estimated small dense low-density lipoprotein cholesterol (sdLDL-C) and the risk of incident nonalcoholic fatty liver disease (NAFLD) in nonobese populations. MATERIALS AND METHODS: This study included participants who underwent health checkups in 2014 and were followed up until 2019. We carried out Cox proportional hazards regression analyses to evaluate the association of estimated sdLDL-C with NAFLD. Discordance analyses were carried out to estimate the relative NAFLD risk in estimated sdLDL-C versus low-density lipoprotein cholesterol (LDL-C) discordant/concordant groups. Estimated sdLDL-C was calculated by equations based on LDL-C and triglycerides. The diagnosis of NAFLD was based on the presence of abdominal ultrasonography after excluding other causes of chronic liver disease. RESULTS: Over a mean follow-up period of 26,694 person-years, 844 incident NAFLD cases were recorded. Compared with the first quartile of estimated sdLDL-C, the fourth quartile was associated with a 2.933-fold increased risk of NAFLD (95% confidence interval 2.095-4.107). With the increase in estimated sdLDL-C, the risk of NAFLD gradually increased both in participants within the normal range of LDL-C (hazard ratio 2.854, 95% confidence interval 1.650-5.617) and beyond the normal range of LDL-C (hazard ratio 2.636, 95% confidence interval 1.263-5.502). In addition, the inconsistent high estimated sdLDL-C/low LDL-C group was associated with an increased risk of NAFLD, but not the low estimated sdLDL-C/high LDL-C group. CONCLUSIONS: Estimated sdLDL-C was positively associated with the risk of incident NAFLD in a nonobese population, independent of LDL-C.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , LDL-Colesterol , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Fatores de Risco , Biomarcadores , Triglicerídeos
4.
Chin Med Sci J ; 38(4): 309-314, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38073063

RESUMO

Hepatocelluar carcinoma presenting as a biliary duct tumor thrombus is a relatively rare entity, with poor prognosis. The primary clinical manifestation of this disease is obstructive jaundice, which can often be misdiagnosed. A 59-year-old female patient was admitted with sudden onset of abdominal pain. Laboratory tests suggested obstructive jaundice, and enhanced magnetic resonance imaging of the upper abdomen did not show obvious biliary dilatation. Endoscopic ultrasound and endoscopic retrograde cholangiopancreatography suggested an occupying lesion in the upper bile duct. SpyGlass and biopsy finally confirmed hepatocellular carcinoma with right hepatic duct tumor thrombus hemorrhage. The SpyGlass Direct Visualization System, as an advanced biliary cholangioscopy device, showed the advantages of single-person operation as well as easy access to and visualization of the lesion.


Assuntos
Carcinoma Hepatocelular , Icterícia Obstrutiva , Neoplasias Hepáticas , Trombose , Feminino , Humanos , Pessoa de Meia-Idade , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/diagnóstico por imagem , Icterícia Obstrutiva/etiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagem , Ducto Hepático Comum/patologia , Trombose/diagnóstico por imagem , Trombose/complicações , Hemorragia/complicações
5.
PLoS One ; 18(11): e0288309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37917736

RESUMO

Vegetables represent an important agricultural industry in China. New farmers and new technologies for vegetable production have emerged in recent years, which makes farmer training very necessary. On the other hand, massive open online courses (MOOCs) are currently widely used in universities. The purpose of this study is to investigate the importance of different sections of a university MOOC focused on olericulture to farmers with different demographic characteristics and provide a basis to improve university MOOCs for farmer training. The survey results suggest that the age, education level, gender, farmer scale, facility type and profit of farmer learners are important factors determining evaluations of the importance of different MOOC sections, indicating that services customized to different farmer populations are necessary. Among different sections of MOOC "Olericulture", farmers with younger age, higher education, larger farm, more advanced facility and more profit were more interesting in sections include cultural, social and theoretical knowledge, and less interesting in practical skill sections. Based on the survey, eight new sections including one marketing subsection (new agricultural supplies and market news), one social subsection (laws and regulations), two practical subsections (practice videos, photos and videos from other farms), and three comprehensive subsections (discussion of practical issues, mechanization, and smart olericulture) were added to the original MOOC, and the results indicate that this improvement is efficient in enhancing the importance evaluations and profits of all farmer learners, especially among those with high education levels.


Assuntos
Educação a Distância , Humanos , Educação a Distância/métodos , Universidades , Fazendeiros , Avaliação Educacional , Escolaridade
6.
EClinicalMedicine ; 66: 102314, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38024480

RESUMO

Background: Pembrolizumab plus trastuzumab and chemotherapy showed remarkable efficacy as first-line therapy for advanced HER2-positive gastric cancer. Pyrotinib is an irreversible pan-HER inhibitor. This single-arm, open-label phase 1 dose-escalation (1a) and expansion (1b) study investigated camrelizumab, an anti-PD-1 antibody, plus pyrotinib and chemotherapy as first-line treatment for advanced HER2-positive gastric and gastroesophageal junction (G/GEJ) adenocarcinoma. Methods: Between June 2020 and June 2022, 41 patients with previously untreated HER2-positive locally advanced unresectable or metastatic G/GEJ adenocarcinoma were enrolled. In phase 1a, patients underwent a 3 + 3 escalating dose design, receiving oral pyrotinib (240 mg, 320 mg, or 400 mg daily), intravenous camrelizumab (200 mg), and CapeOX (oxaliplatin 130 mg/m2 on day 1 and capecitabine 1000 mg/m2 twice daily for two weeks) every 3 weeks until progression, intolerable toxicity or consent withdrawal. The recommended phase 2 dose (RP2D) of pyrotinib was determined and used in the phase 1b. The primary endpoints were the safety, maximum tolerated dose (MTD), RP2D, and confirmed objective response rate (ORR). This trial was registered with chictr.org, number ChiCTR2000029717. Findings: Among 41 patients, 10 were in phase 1a (3 at 240 mg, 3 at 400 mg, and 4 at 320 mg due to one patient withdrawing consent), and 31 were in phase 1b. In phase 1a, the MTD of pyrotinib was 320 mg daily due to dose-limiting toxicities (diarrhea [n = 3] and vomiting [n = 1]) observed at 400 mg. Based on all available data, the RP2D of pyrotinib was set at 320 mg. Among 41 patients, 20 patients (48.8%) developed grade ≥3 treatment-emergent adverse events (TEAEs), and four patients (9.8%) had any grade serious adverse events. No deaths occurred due to TEAEs. Among 27 patients who received the RP2D of pyrotinib and had a post-baseline tumor assessment, two patients (7.4%) achieved a confirmed complete response, and 19 patients (70.4%) achieved a confirmed partial response, resulting in a confirmed ORR of 77.8% (95% CI: 57.7-91.4). Interpretation: Pyrotinib plus camrelizumab and chemotherapy showed promising efficacy in the first-line treatment of advanced HER2-positive G/GEJ cancer. The safety profile was consistent with known toxicities of the agents, and no new or unexpected safety signals were identified. Funding: This study was funded by the Beijing Xisike Clinical Oncology Research Foundation (Y-HR2019-0377).

7.
BMC Genomics ; 24(1): 323, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312060

RESUMO

BACKGROUND: Gastric cancer (GC) carries significant morbidity and mortality globally. An increasing number of studies have confirmed that circular RNA (circRNA) is tightly associated with the carcinogenesis and development of GC, especially acting as a competing endogenous RNA for miRNAs. OBJECTIVE: Our study aimed to construct the circRNA-miRNA-mRNA regulatory network and analyze the function and prognostic significance of the network using bioinformatics tools. METHODS: We first downloaded the GC expression profile from the Gene Expression Omnibus database and identified differentially expressed genes and differentially expressed circRNAs. Then, we predicted the miRNA-mRNA interaction pairs and constructed the circRNA-miRNA-mRNA regulatory network. Next, we established a protein-protein interaction network and analyzed the function of these networks. Finally, we primarily validated our results by comparison with The Cancer Genome Atlas cohort and by performing qRT-PCR. RESULTS: We screened the top 15 hub genes and 3 core modules. Functional analysis showed that in the upregulated circRNA network, 15 hub genes were correlated with extracellular matrix organization and interaction. The function of downregulated circRNAs converged on physiological functions, such as protein processing, energy metabolism and gastric acid secretion. We ascertained 3 prognostic and immune infiltration-related genes, COL12A1, COL5A2, and THBS1, and built a nomogram for clinical application. We validated the expression level and diagnostic performance of key prognostic differentially expressed genes. CONCLUSIONS: In conclusion, we constructed two circRNA-miRNA-mRNA regulatory networks and identified 3 prognostic and screening biomarkers, COL12A1, COL5A2, and THBS1. The ceRNA network and these genes could play important roles in GC development, diagnosis and prognosis.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , MicroRNAs/genética , RNA Circular/genética , Neoplasias Gástricas/genética , RNA Mensageiro/genética , Prognóstico
8.
J Clin Endocrinol Metab ; 108(11): 2907-2915, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37186667

RESUMO

CONTEXT: Serum levels of remnant cholesterol have been reported to predict the prognosis of cardiovascular disease, independent of traditional lipid profiles. OBJECTIVE: This study aimed to explore the association between serum remnant cholesterol and the development of nonalcoholic fatty liver disease (NAFLD). METHODS: A total of 9184 adults who underwent physical examination annually were included in this study. The association between serum remnant cholesterol and incident NAFLD was analyzed by Cox proportional hazards regression. We evaluated the relative risk of NAFLD in the groups with discordant remnant cholesterol vs traditional lipid profiles using clinically relevant treatment targets. RESULTS: During a total of 31 662 person-years of follow-up, 1339 incident NAFLD cases were identified. In the multivariable-adjusted model, the fourth quartile of remnant cholesterol was positively associated with NAFLD risks compared with the first quartile (hazard ratio [HR]: 2.824; 95% CI, 2.268-3.517; P < .001). This association remained significant among individuals with normal levels of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (HR: 1.929; 95% CI, 1.291-2.882; P < .001). In individuals achieving the different treatment targets of LDL-C and non-HDL-C for risk stratification according to clinical guidelines, the association between remnant cholesterol and incident NAFLD was still significant. CONCLUSION: Serum levels of remnant cholesterol have predictive value for the development of NAFLD beyond traditional lipid profiles.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , LDL-Colesterol , Colesterol , Triglicerídeos , HDL-Colesterol , Fatores de Risco
9.
STAR Protoc ; 4(2): 102339, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37243598

RESUMO

The pathogens of the Diaporthe genus are now considered to be the dominant pathogens of kiwifruit soft rot. Here, we present a protocol to construct nanoprobes for the Diaporthe genus and detect changes of surface-enhanced Raman spectroscopy for samples collected from infected kiwifruit. We describe steps for synthesis of gold nanoparticles, DNA extraction from kiwifruit, and construction of nanoprobes. We then detail classification of nanoparticles with different aggregation states through dark-field microscope (DFM) picture analysis using Fiji-ImageJ software. For complete details on the use and execution of this protocol, please refer to Yu et al. (2022).1.

10.
Talanta ; 258: 124447, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36921366

RESUMO

The kiwi plant is dioecious, and its sex is generally identified from flower morphology at blossoming, which takes several years. It is quite necessary but challenging to on-spot identify the plant sex in juvenile stage. Here the target DNA was obtained by screening the Friendly boy (FrBy) gene which is sex-related for different kiwi plant species. Its complementary sequence was divided into two parts as primer DNA and further attached to different gold nanoparticles (GNPs). The connection between target DNA and primer DNA will promote the formation of plasmonic dimers. Dark field microscopy (DFM) can distinguish particles in different aggregation states. Various conditions were optimized based on the standard of increasing the proportion of dimers while reducing that of large aggregates. Furthermore, two Raman reporters (RR) are separately labeled on the nanoprobes, and the plasmonic dimers lead to a tremendous Raman enhancement of two reporters located at the dimer nanogap. Double-blind tests proved the feasibility of this method on the actual samples of kiwi plant leaves. Our SERS method is sensitive, specific, and reliable for rapid sex identification analysis at the kiwi seeding stage, with great promise for decision-making in field management.


Assuntos
Actinidia , Nanopartículas Metálicas , Humanos , DNA , Ouro , Polímeros , Análise Espectral Raman/métodos , Método Duplo-Cego
11.
New Phytol ; 238(6): 2440-2459, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36922399

RESUMO

Previous discovering meticulously illustrates the post-translational modifications and protein stability regulation of ICE1 and their role in cold stress. However, the studies on the interaction of ICE1 with other transcription factors, and their function in modulation cold stress tolerance, as well as in the transition between cold stress and growth are largely insufficient. In this work, we found that maltose binding protein (MBP) 43 directly binds to the promoters of CBF genes to repress their expression, thereby negatively regulating freezing tolerance. Biochemical and genetic analyses showed that MYB43 interacts and antagonizes with ICE1 to regulate the expression of CBF genes and plant's freezing stress tolerance. PLEIOTROPIC REGULATORY LOCUS 1 (PRL1) accumulates under cold stress and promotes MYB43 protein degradation; however, when cold stress disappears, PRL1 restores normal protein levels, causing MYB43 protein to re-accumulate to normal levels. Furthermore, PRL1 positively regulates freezing tolerance by promoting degradation of MYB43 to attenuate its repression of CBF genes and antagonism with ICE1. Thus, our study reveals that MYB43 inhibits CBF genes expression under normal growth condition, while PRL1 promotes MYB43 protein degradation to attenuate its repression of CBF genes and antagonism with ICE1, and thereby to the precise modulation of plant cold stress responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Congelamento , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/metabolismo
12.
Plant Cell Environ ; 46(5): 1653-1670, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36738191

RESUMO

Cadmium (Cd) is one of the most dangerous environmental pollutants among heavy metals, and threatens food safety and human health by accumulating in plant sink tissues. Here, we report a novel regulatory cascade that profoundly influences Cd tolerance in Arabidopsis. Phenotypic analysis showed that an insertional knockdown mutation at the Arabidopsis Tóxicos en Levadura 31 (ATL31) locus resulted in hypersensitivity to Cd stress, most likely due to a significant increase in Cd accumulation. Consistently, ATL31-overexpressing lines exhibited enhanced Cd stress tolerance and reduced Cd accumulation. Further, IRON-REGULATED TRANSPORTER 1 (IRT1) was identified, and yeast two-hybrid, co-immunoprecipitation and bimolecular fluorescence complementation assays demonstrated its interaction with ATL31. Biochemical, molecular, and genetic analyses showed that IRT1 is targeted by ATL31 for ubiquitin-conjugated degradation in response to Cd stress. Intriguingly, transcription of ATL31 was strongly induced by Cd stress. In addition, transgenic and molecular analyses showed that WRKY33 directly activated the transcription of ATL31 in response to Cd stress and positively regulated Cd tolerance. Genetic analysis indicated that ATL31 acts upstream of IRT1 and downstream of WRKY33 to regulate Cd tolerance. Our study revealed that the WRKY33-ATL31-IRT1 module plays a crucial role in timely blocking Cd absorption to prevent metal toxicity in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Transporte de Cátions , Metais Pesados , Humanos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Metais Pesados/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
Nanoscale ; 15(7): 3199-3211, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36723123

RESUMO

Zinc molybdate (ZMO) is a safe and effective grafting material for anticorrosion. Herein, we reported the synthesis of ZMO/h-BN with the labyrinth of capillary pores owing to the in situ growth of ZMO on flake hexagonal boron nitride (h-BN) using the hydrothermal method. The special morphological structure provided a tortuous path for aggressive species to the steel substrate, which extended and blocked the transmission of aggressive species, enhancing the physical corrosion barrier performance. In addition, the capillary pores of ZMO contributed to the competitive adsorption of Cl- in an electrolyte and reduced the diffusion of aggressive species, thus further delaying the corrosion process. Moreover, the capture of oxygen by forming a B-O bond with h-BN and the formation of a molybdate passive film are beneficial for the inhibition of cathodic and anodic reactions. As verified by electrochemical impedance spectroscopy (EIS), the anticorrosion performance of ZMO/h-BN coating increased by 49.58% and 130.72% compared with ZMO and epoxy resin (EP) coatings after immersing in a NaCl aqueous solution (3.50 wt%) for 72 h. This coating matrix provides an avenue for molybdate-based corrosion remediation.

14.
J Fungi (Basel) ; 9(1)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36675948

RESUMO

Biological control of postharvest diseases has been proven to be an effective alternative to chemical control. As an environmentally friendly biocontrol agent, Bacillus subtilis has been widely applied. This study explores its application in kiwifruit soft rot and reveals the corresponding mechanisms. Treatment with cell-free supernatant (CFS) of Bacillus subtilis BS-1 significantly inhibits the mycelial growth of the pathogen Botryosphaeria dothidea and attenuates the pathogenicity on kiwifruit in a concentration-dependent manner. In particular, mycelial growth diameter was only 21% of the control after 3 days of treatment with 5% CFS. CFS caused swelling and breakage of the hyphae of B. dothidea observed by scanning electron microscopy, resulting in the leakage of nucleic acid and soluble protein and the loss of ergosterol content. Further analysis demonstrated that CFS significantly induces the expression of Nox genes associated with reactive oxygen species (ROS) production by 1.9-2.7-fold, leading to a considerable accumulation of ROS in cells and causing mycelial cell death. Our findings demonstrate that the biocontrol effect of B. subtilis BS-1 CFS on B. dothidea is realized by inducing oxidative damage to the mycelia cell.

15.
iScience ; 25(12): 105650, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36479145

RESUMO

Diaporthe genus is the dominant pathogens of kiwifruit soft rot with long incubation period and rapid onset and very hard to detect in advance. It is of great significance to develop point-of-care tests for disease prevention and field management. Here we screen a pair of genus-level primers for constructing plasmonic dimer Rayleigh/Raman spectroscopy, which enables rapid, specific, and sensitive detection of Diaporthe genus in real kiwifruits. Dark-filed Rayleigh scattering clearly visualizes the target-induced dimer assembly of nanoprobes. Plasmonic dimer-enhanced Raman spectroscopy has high specificity for 12 common isolates of Diaporthe genus in one batch samples with highly accurate results and much higher sensitivity than polymerase chain reaction (PCR). It realizes the recognition of Diaporthe infection at an early stage of 24 h when the kiwifruits do not have any noticeable symptoms. It demonstrates a bright prospect of point-of-care tests for early warning of kiwifruit soft rot infection and quality control.

16.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361943

RESUMO

Size is the most important quality attribute of giant pumpkin fruit. Different concentrations and application frequencies of α-naphthaleneacetic acid (NAA) and 24-epibrassinolide (EBR) were sprayed on the leaves and fruits of giant pumpkin at different growth stages to determine their effects and the mechanism responsible for fruit size increase. NAA+EBR application improved source strength, and further analysis indicated that NAA+EBR markedly boosted net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr) and the expression level and activity of galactitol synthetase (GolS), raffinose synthetase (RS), and stachyose synthetase (STS), resulting in an increase in the synthesis of photoassimilate, especially stachyose. Concomitantly, NAA+EBR spray increased stachyose and sucrose contents throughout pumpkin fruit growth and the concentrations of glucose and fructose at 0 and 20 days post-anthesis (DPA) in peduncle phloem sap, implying that such treatment improved the efficiency of assimilate transport from the peduncle to the fruit. Furthermore, it improved the expression and activity of alkaline α-galactosidase (AGA), facilitating assimilate unloading, providing carbon skeletons and energy for fruit growth, and increasing fruit weight by more than 44.1%. Therefore, exogenous NAA and EBR increased source capacity, transportation efficiency, and sink strength, overall promoting the synthesis and distribution of photoassimilate, ultimately increasing fruit size.


Assuntos
Cucurbita , Frutas , Frutas/metabolismo , Açúcares/metabolismo , Ligases/metabolismo
17.
Plant Cell Environ ; 45(12): 3537-3550, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36128662

RESUMO

The tomato transcription factor SlNAC1 plays an important role in abiotic stress response and is fine-tuned at both transcriptional and posttranslational levels. The SlNAC1 gene is strongly induced by multiple abiotic stresses and the SlNAC1 protein is subjected to ubiquitin proteasome-mediated degradation. We found here that SlNAC1 possesses two distinct transactivation domains (TADs), TAD1 and TAD2. Significantly, the instability of SlNAC1 was attributed to the acidic amino acid-rich TAD1, in which the instability and transcriptional potential of TAD1 functionally overlapped; whereas the glutamine-rich TAD2 was stable and accounted for the abiotic stress signalling mediated by SlNAC1. Towards the goal of enhanced tolerance to abiotic stress in tomatoes, we manipulated SlNAC1 at both gene and protein levels: we generated a stable and functional SlNAC1 mutant SlNAC1∆191-270 by removing TAD1 and further engineered it to be stress-controllable by fusing the corresponding cDNA with the abiotic stress-inducible promoter ProStNAC1 . Transgenic tomato plants expressing the ProStNAC1 ::SlNAC1∆191-270 transgene did not display any undesired traits and exhibited enhanced tolerance to cold, drought and salt stresses. Taken together, our manipulation of the stress-related transcription factor via conditional expression of its derived stable and functional mutant provides a successful example for developing crops dynamically adapted to abiotic stress.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Secas , Plantas Geneticamente Modificadas/metabolismo
18.
Helicobacter ; 27(5): e12920, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35939548

RESUMO

BACKGROUND: Resistance of Helicobacter pylori (H. pylori) to antibiotics is an evolving and dynamic process. Presence of antibiotic resistance impacts the success rate of initial eradication strategies in the clinic. AIM: To improve the success rate of initial eradication therapy and explore new antibiotic regimens, a large sample-based study utilizing antimicrobial susceptibility testing was performed. A total of 2508 H. pylori strains from patients subjected to initial eradication therapy were isolated, cultured, and tested for drug susceptibility from 2017 to 2021. The minimal inhibitory concentration (MIC) was recorded. H. pylori susceptibility profiles and its change trends from initial eradication patients were analyzed. The relationships between drug resistance, year of sample collection, age, and sex of patients were analyzed. RESULTS: The overall resistance rates were as follows: amoxicillin (9.25%), clarithromycin (38.48%), levofloxacin (42.86%), furazolidone (11.28%), doxycycline (8.56%), rifampicin (10.81%), tinidazole (74.32%), gatifloxacin (61.71%), tetracycline (0%), metronidazole (78.71%), ornidazole (97.87%), and fosfomycin (31.67%). Only 38.04% of the strains were pansusceptible to amoxicillin, clarithromycin, levofloxacin, and furazolidone, followed by those of mono resistance (29.90%), double resistance (24.96%), triple resistance (6.34%), and quadruple resistance (0.76%). Significant differences in the resistance rate and MIC were also observed in different age and sex groups. Time of collection and patient age and sex were associated with the distribution of antibiotic resistance. CONCLUSION: With the increasing resistance rate and multiple resistance of H. pylori to commonly used antibiotics, drug susceptibility testing is imperative to permit individualized therapy, and a regimen containing the combination of amoxicillin, furazolidone, tetracycline, doxycycline, or rifampicin is reasonable for initial empirical eradication therapy.


Assuntos
Fosfomicina , Infecções por Helicobacter , Helicobacter pylori , Mycobacterium tuberculosis , Ornidazol , Amoxicilina/farmacologia , Amoxicilina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , Doxiciclina/uso terapêutico , Farmacorresistência Bacteriana , Fosfomicina/uso terapêutico , Furazolidona/uso terapêutico , Gatifloxacina/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Humanos , Levofloxacino/uso terapêutico , Metronidazol/uso terapêutico , Testes de Sensibilidade Microbiana , Ornidazol/uso terapêutico , Rifampina , Tinidazol/uso terapêutico
19.
Front Microbiol ; 13: 980022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992680

RESUMO

As a notorious pathogenic fungus, Botrytis cinerea has been reported to infect more than 1400 species of plants and cause postharvest gray mold of numerous economic fruits, leading to substantial economic losses. Traditional chemical fungicides in pathogen control have potential issues regarding environmental pollution, disease resistance and human health. More safety and efficacious prevention technique of postharvest gray mold are in urgent demand. This study aims to investigate the potential function and mechanism of Bacillus velezensis to control gray mold for harvested fruits. The results showed that the cell-free supernatant (CFS) generated from B. velezensis strain A4 was able to inhibit spore germination, germ tube elongation and hyphal growth of B. cinerea in vitro, and impair the pathogenicity of B. cinerea on the four tested fruits. Further analysis demonstrated that CFS significantly reduced the expression of genes associated with growth and pathogenicity and weakened the ability of B. cinerea spores to penetrate plant cell walls in a dose-dependent manner. Moreover, the CFS destroyed the membrane of hyphae, resulting in exosmosis of cell contents and caused hyphal cells to accumulate excessive reactive oxygen species (ROS), leading to hyphal oxidative damage. Our findings indicate that B. velezensis CFS can damage B. cinerea mycelial cells by promoting excessive accumulation of ROS to realize its biological control function.

20.
ACS Appl Mater Interfaces ; 14(31): 36258-36267, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35881933

RESUMO

Indium tin oxide (ITO) thin films suffer from poor chemical stability at high temperatures because of the instability of point defects and structural variations. An interface design strategy was proposed herein to improve this situation, where a robust ITO-based thin film with a column-layer structure was fabricated. Three types of column-layer ITO thin films were fabricated via magnetron sputtering. By tuning the interfaces, we controlled the effective mass and weighted mobility, enhancing the electrical conductivity (2.17 × 106 S m-1) and power factor (1138 µW m-1 K-2). The crack propagation path was prolonged because of the profuse interfaces between the columns and layers in the alternate thin films. Thus, enhanced nanohardness (16.5 GPa) was obtained. The structural evolution and performance of the column-layer ITO thin films annealed under different conditions were investigated. The atoms were restricted by the profuse interfaces, resulting in high-temperature stability. The results demonstrate that the interface design of ITO thin films can efficiently modify the stability of conductive ceramics over a wide temperature range, which has significant potential for applications in microdevices and aero engines.

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