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1.
Nat Immunol ; 23(5): 705-717, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35487985

RESUMO

Caspase-11 detection of intracellular lipopolysaccharide (LPS) from invasive Gram-negative bacteria mediates noncanonical activation of the NLRP3 inflammasome. While avirulent bacteria do not invade the cytosol, their presence in tissues necessitates clearance and immune system mobilization. Despite sharing LPS, only live avirulent Gram-negative bacteria activate the NLRP3 inflammasome. Here, we found that bacterial mRNA, which signals bacterial viability, was required alongside LPS for noncanonical activation of the NLRP3 inflammasome in macrophages. Concurrent detection of bacterial RNA by NLRP3 and binding of LPS by pro-caspase-11 mediated a pro-caspase-11-NLRP3 interaction before caspase-11 activation and inflammasome assembly. LPS binding to pro-caspase-11 augmented bacterial mRNA-dependent assembly of the NLRP3 inflammasome, while bacterial viability and an assembled NLRP3 inflammasome were necessary for activation of LPS-bound pro-caspase-11. Thus, the pro-caspase-11-NLRP3 interaction nucleated a scaffold for their interdependent activation explaining their functional reciprocal exclusivity. Our findings inform new vaccine adjuvant combinations and sepsis therapy.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Caspase 1/metabolismo , Caspases , Bactérias Gram-Negativas , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , RNA Mensageiro
2.
Nucleic Acids Res ; 51(16): 8322-8336, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37486780

RESUMO

Sensors to measure the abundance and signaling of intracellular molecules are crucial for understanding their physiological functions. Although conventional fluorescent protein-based sensors have been designed, RNA-based sensors are promising imaging tools. Numerous RNA-based sensors have been developed. These sensors typically contain RNA G-quadruplex (RG4) motifs and thus may be suboptimal in living cells. Here we describe RNA-based sensors based on Pepper, a fluorogenic RNA without an RG4 motif. With Pepper, we engineered various sensors for metabolites, synthetic compounds, proteins and metal ions in vitro and in living cells. In addition, these sensors show high activation and selectivity, demonstrating their universality and robustness. In the case of sensors responding to S-adenosylmethionine (SAM), a metabolite produced by methionine adenosyltransferase (MATase), we showed that our sensors exhibited positively correlated fluorescence responding to different SAM levels. Importantly, we revealed the SAM biosynthesis pathway and monitored MATase activity and gene expression spatiotemporally in living individual human cells. Additionally, we constructed a ratiometric SAM sensor to determine the inhibition efficacy of a MATase inhibitor in living cells. Together, these sensors comprising Pepper provide a useful platform for imaging diverse cellular targets and their signaling pathway.


Assuntos
Aptâmeros de Nucleotídeos , RNA , Humanos , RNA/genética , RNA/metabolismo , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Corantes Fluorescentes/metabolismo , Fluorescência
3.
Plant J ; 115(2): 398-413, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37021636

RESUMO

The potato's most devastating disease is late blight, which is caused by Phytophthora infestans. Whereas various resistance (R) genes are known, most are typically defeated by this fast-evolving oomycete pathogen. However, the broad-spectrum and durable R8 is a vital gene resource for potato resistance breeding. To support an educated deployment of R8, we embarked on a study on the corresponding avirulence gene Avr8. We overexpressed Avr8 by transient and stable transformation, and found that Avr8 promotes colonization of P. infestans in Nicotiana benthamiana and potato, respectively. A yeast-two-hybrid (Y2H) screen showed that AVR8 interacts with a desumoylating isopeptidase (StDeSI2) of potato. We overexpressed DeSI2 and found that DeSI2 positively regulates resistance to P. infestans, while silencing StDeSI2 downregulated the expression of a set of defense-related genes. By using a specific proteasome inhibitor, we found that AVR8 destabilized StDeSI2 through the 26S proteasome and attenuated early PTI responses. Altogether, these results indicate that AVR8 manipulates desumoylation, which is a new strategy that adds to the plethora of mechanisms that Phytophthora exploits to modulate host immunity, and StDeSI2 provides a new target for durable resistance breeding against P. infestans in potato.


Assuntos
Phytophthora infestans , Solanum tuberosum , Melhoramento Vegetal , Imunidade Vegetal , Solanum tuberosum/genética , Doenças das Plantas
4.
BMC Genomics ; 25(1): 673, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969975

RESUMO

BACKGROUND: Culex tritaeniorhynchus is widely distributed in China, from Hainan Island in the south to Heilongjiang in the north, covering tropical, subtropical, and temperate climate zones. Culex tritaeniorhynchus carries 19 types of arboviruses. It is the main vector of the Japanese encephalitis virus (JEV), posing a serious threat to human health. Understanding the effects of environmental factors on Culex tritaeniorhynchus can provide important insights into its population structure or isolation patterns, which is currently unclear. RESULTS: In total, 138 COI haplotypes were detected in the 552 amplified sequences, and the haplotype diversity (Hd) value increased from temperate (0.534) to tropical (0.979) regions. The haplotype phylogeny analysis revealed that the haplotypes were divided into two high-support evolutionary branches. Temperate populations were predominantly distributed in evolutionary branch II, showing some genetic isolation from tropical/subtropical populations and less gene flow between groups. The neutral test results of HNQH (Qionghai) and HNHK(Haikou) populations were negative (P < 0.05), indicating many low-frequency mutations in the populations and that the populations might be in the process of expansion. Moreover, Wolbachia infection was detected only in SDJN (Jining) (2.24%), and all Wolbachia genotypes belonged to supergroup B. To understand the influence of environmental factors on mosquito-borne viruses, we examined the prevalence of Culex tritaeniorhynchus infection in three ecological environments in Shandong Province. We discovered that the incidence of JEV infection was notably greater in Culex tritaeniorhynchus from lotus ponds compared to those from irrigation canal regions. In this study, the overall JEV infection rate was 15.27 per 1000, suggesting the current risk of Japanese encephalitis outbreaks in Shandong Province. CONCLUSIONS: Tropical and subtropical populations of Culex tritaeniorhynchus showed higher genetic diversity and those climatic conditions provide great advantages for the establishment and expansion of Culex tritaeniorhynchus. There are differences in JEV infection rates in wild populations of Culex tritaeniorhynchus under different ecological conditions. Our results suggest a complex interplay of genetic differentiation, population structure, and environmental factors in shaping the dynamics of Culex tritaeniorhynchus. The low prevalence of Wolbachia in wild populations may reflect the recent presence of Wolbachia invasion in Culex tritaeniorhynchus.


Assuntos
Culex , Haplótipos , Filogenia , Culex/genética , Culex/virologia , Culex/microbiologia , Animais , China , Clima , Variação Genética , Genética Populacional , Wolbachia/genética , Mosquitos Vetores/genética , Mosquitos Vetores/virologia , Mosquitos Vetores/microbiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética
5.
J Gene Med ; 26(1): e3640, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37989259

RESUMO

BACKGROUND: LentiGlobin BB305 is a self-inactivating lentiviral vector carrying a human ß-globin expressing cassette for treating ß-thalassemia. Initially, a 2 × 250 bp chicken Locus Control Region fragment of cHS4, functioning as an insulator, was placed at its ΔU3, which was removed after the first clinical trial led by a French team to avoid abnormal splicing, etc. This action could potentially lead to an increasing risk of the transcriptional read-through rate driven by the ß-globin promoter to a significant level, posing a biosafety risk in clinical trials. METHODS: In the present study, a read-through reducing agent (C-U+ or WPRE) was designed to be placed at the 3' UTR of the ß-globin gene. The Enhancer Activities and/or Transcriptional Read-Through (EATRT) rate at the mRNA level and the protein expression level regarding lentiviral preparation titer were examined. RESULTS: We found that the insertion of the element (C-U+ or WPRE) reduced the EATRT effectively by 53% or 41%, respectively. C-U+ has less impact on virus package efficiency. Furthermore, there was no significant difference in the protein expression level after the C-U+ or WPRE insertion. CONCLUSIONS: The results of the present study show that inserting C-U+ or WPRE before the polyA sequence of the BB305 would reduce the EATRT rate at no cost of its expressing efficacy and viral preparation titers. Thus, we present an alternative improvement for a safer lentiviral vector for ß-thalassemia clinical trials.


Assuntos
Talassemia beta , Humanos , Talassemia beta/genética , Talassemia beta/terapia , Lentivirus/genética , Vetores Genéticos/genética , Terapia Genética/métodos , Globinas beta/genética
6.
J Neuroinflammation ; 21(1): 99, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632655

RESUMO

BACKGROUND: The pathogenesis of memory impairment, a common complication of chronic neuropathic pain (CNP), has not been fully elucidated. Schwann cell (SC)-derived extracellular vesicles (EVs) contribute to remote organ injury. Here, we showed that SC-EVs may mediate pathological communication between SCs and hippocampal neurons in the context of CNP. METHODS: We used an adeno-associated virus harboring the SC-specific promoter Mpz and expressing the CD63-GFP gene to track SC-EVs transport. microRNA (miRNA) expression profiles of EVs and gain-of-function and loss-of-function regulatory experiments revealed that miR-142-5p was the main cargo of SC-EVs. Next, luciferase reporter gene and phenotyping experiments confirmed the direct targets of miR-142-5p. RESULTS: The contents and granule sizes of plasma EVs were significantly greater in rats with chronic sciatic nerve constriction injury (CCI)than in sham rats. Administration of the EV biogenesis inhibitor GW4869 ameliorated memory impairment in CCI rats and reversed CCI-associated dendritic spine damage. Notably, during CCI stress, SC-EVs could be transferred into the brain through the circulation and accumulate in the hippocampal CA1-CA3 regions. miR-142-5p was the main cargo wrapped in SC-EVs and mediated the development of CCI-associated memory impairment. Furthermore, α-actinin-4 (ACTN4), ELAV-like protein 4 (ELAVL4) and ubiquitin-specific peptidase 9 X-linked (USP9X) were demonstrated to be important downstream target genes for miR-142-5p-mediated regulation of dendritic spine damage in hippocampal neurons from CCI rats. CONCLUSION: Together, these findings suggest that SCs-EVs and/or their cargo miR-142-5p may be potential therapeutic targets for memory impairment associated with CNP.


Assuntos
Vesículas Extracelulares , MicroRNAs , Neuralgia , Ratos , Animais , MicroRNAs/metabolismo , Neuralgia/metabolismo , Neurônios/metabolismo , Células de Schwann/metabolismo , Vesículas Extracelulares/metabolismo
7.
Am Heart J ; 278: 33-40, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39182902

RESUMO

BACKGROUND: Co-morbid hypertension is strong predictor of adverse cardiovascular (CV) outcomes in patients with atrial fibrillation (AF) but the optimal target for blood pressure (BP) control in this patient population has not been clearly defined. METHODS: The Cardiovascular Risk reduction in patients with Atrial Fibrillation Trial (CRAFT) is an investigator-initiated and conducted, international, multicenter, open-label, parallel-group, blinded outcome assessed, randomized controlled trial of intensive BP control in patients with AF. The aim is to determine whether intensive BP control (target home systolic blood pressure [SBP] <120 mmHg) is superior to standard BP control (home SBP <135 mmHg) on the hierarchical composite outcome of time to CV death, number of stroke events, time to the first stroke, number of myocardial infarction (MI) events, time to the first MI, number of heart failure hospitalization (HFH) events, and time to the first HFH. A sample size of 1,675 patients is estimated to provide 80% power to detect a win-ratio of 1.50 for intensive versus standard BP control on the primary composite outcome. Study visits are conducted at 1, 2, 3, and 6 months postrandomization, and every 6 months thereafter during the study. CONCLUSIONS: This clinical trial aims to provide reliable evidence of the effects of intensive BP control in patients with AF. TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (NCT04347330).

8.
Arch Microbiol ; 206(8): 350, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995446

RESUMO

KKL-35 is a new oxadiazole compound with potent broad-spectrum antibacterial activity against a number of gram-positive and gram-negative bacteria. However, its influences on bacterial growth are unclear. This study is to investigate phenotypic changes of Staphylococcus aureus (SA) caused by KKL-35 and evaluate antibacterial activity of combinations of KKL-35 with 7 class of antibiotics available in medical facilities. KKL-35-treated SA showed significantly lower survival under stresses of NaCl and H2O2 than DMSO (21.03 ± 2.60% vs. 68.21 ± 5.31% for NaCl, 4.91 ± 3.14% vs. 74.78 ± 2.88% for H2O2). UV exposure significantly decreased survival of SA treated with KKL-35 than DMSO-treated ones (23.91 ± 0.71% vs. 55.45 ± 4.70% for 4.2 J/m2, 12.80 ± 1.03% vs. 31.99 ± 5.99% for 7.0 J/m2, 1.52 ± 0.63% vs. 6.49 ± 0.51% for 14.0 J/m2). KKL-35 significantly decreased biofilm formation (0.47 ± 0.12 vs. 1.45 ± 0.21) and bacterial survival in the serum resistance assay (42.27 ± 2.77% vs. 78.31 ± 5.64%) than DMSO. KKL-35 significantly decreased ethidium bromide uptake and efflux, as well as the cell membrane integrity. KKL-35 had low cytotoxicity and low propensity for resistance. KKL-35 inhibited SA growth in concentration-independent and time-dependent manners, and showed additivity when combined with the majority class of available antibiotics. Antibiotic combinations of KKL-35 with ciprofloxacin, rifampicin, or linezolid significantly decreased bacterial loads than the most active antibiotic in the corresponding combination. Thus, KKL-35 inhibits growth of SA by decreasing bacterial environmental adaptations, biofilm formation, membrane uptake and efflux, as well as increasing antibiotic sensitivity. Its potent antibacterial activity, low cytotoxicity, low propensity for resistance, and wide choices in antibiotic combinations make KKL-35 a promising leading compound to design new antibiotics in monotherapies and combination therapies to treat bacterial infections.


Assuntos
Antibacterianos , Biofilmes , Testes de Sensibilidade Microbiana , Oxidiazóis , Staphylococcus aureus , Humanos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Oxidiazóis/farmacologia , Fenótipo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
9.
Arch Microbiol ; 206(4): 154, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478112

RESUMO

Although the trans-translation system is a promising target for antcibiotic development, its antibacterial mechanism in Klebsiella pneumoniae (KP) is unclear. Considering that tmRNA was the core component of trans-translation, this study firstly investigated phenotypic changes caused by various environmental stresses in KP lacking trans-translation activities (tmRNA-deleted), and then aimed to evaluate antibacterial activities of the trans-translation-targeting antibiotic combination (tobramycin/ciprofloxacin) in clinical KP isolates based on inhibition activities of aminoglycosides against trans-translation. We found that the tmRNA-deleted strain P4325/ΔssrA was significantly more susceptible than the wild-type KP strain P4325 under environments with hypertonicity (0.5 and 1 M NaCl), hydrogen peroxide (40 mM), and UV irradiation. No significant differences in biofilm formation and survivals under human serum were observed between P4325/ΔssrA and P4325. tmRNA deletion caused twofold lower MIC values for aminoglycosides. As for the membrane permeability, tmRNA deletion increased ethidium bromide (EtBr) uptake of KP in the presence or absence of verapamil and carbonyl cyanide-m-chlorophenylhydrazone (CCCP), decreased EtBr uptake in presence of reserpine in P4325/ΔssrA, and reduced EtBr efflux in P4325/ΔssrA in the presence of CCCP. The time-kill curve and in vitro experiments revealed significant bactericidal activities of the tmRNA-targeting aminoglycoside-based antibiotic combination (tobramycin/ciprofloxacin). Thus, the corresponding tmRNA-targeting antibiotic combinations (aminoglycoside-based) might be effective and promising treatment options against multi-drug resistant KP.


Assuntos
Ciprofloxacina , Klebsiella pneumoniae , Humanos , Ciprofloxacina/farmacologia , Klebsiella pneumoniae/genética , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Antibacterianos/farmacologia , Aminoglicosídeos/farmacologia , Tobramicina/farmacologia , Testes de Sensibilidade Microbiana
10.
Pharmacol Res ; 205: 107232, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825157

RESUMO

Type 3 resistant starch from Canna edulis (Ce-RS3) is an insoluble dietary fiber which could improve blood lipids in animals, but clinically robust evidence is still lacking. We performed a double-blind randomized controlled trial to assess the effects of Ce-RS3 on lipids in mild hyperlipidemia. One hundred and fifteen patients were included followed the recruitment criteria, and were randomly allocated to receive Ce-RS3 or placebo (native starch from Canna edulis) for 12 weeks (20 g/day). In addition to serum lipids, complete blood counts, serum inflammatory factors, antioxidant indexes, and dietary survey, 16 S rRNA sequencing technique was utilized to analyze the gut microbiota alterations. Targeted quantitative metabolomics (TQM) was used to detect metabolite changes. Compared with the placebo, Ce- RS3 significantly decreased levels of total cholesterol, lowdensity lipoprotein cholesterol, and non-high-density lipoprotein cholesterol, and increased the glutathione peroxidase. Based on the 16 S rRNA sequencing, TQM, the correlation analysis, as well as the Kyoto Encyclopedia of Genes (KEGG) and Genomes and Human Metabolome Database (HMDB) analysis, we found that Ce-RS3 could increase the abundances of genera Faecalibacterium and Agathobacter, while reduce the abundances of genera norank_f_Ruminococcaceae and Christensenellaceae_R-7_ group to regulate phenylalanine metabolism, which could reduce the fatty acid biosynthesis and fatty acid elongation in the mitochondria to lower blood lipids. Conclusively, we firstly confirmed the feasibility of Ce-RS3 for clinical application, which presents a novel, effective therapy for the mild hyperlipidemia. (Chictr. org. cn. Clinical study on anti-mild hyperlipidemia of Canna edulis RS3 resistant starch, ID Number: ChiCTR2200062871).


Assuntos
Microbioma Gastrointestinal , Hiperlipidemias , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos , Método Duplo-Cego , Masculino , Pessoa de Meia-Idade , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/sangue , Hiperlipidemias/microbiologia , Feminino , Adulto , Lipídeos/sangue , Amido Resistente , Amido , Hipolipemiantes/uso terapêutico , Hipolipemiantes/farmacologia , Idoso
11.
J Phys Chem A ; 128(19): 3801-3811, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38709493

RESUMO

The 2-(2-aminophenyl)naphthalene molecule attracted much attention due to excited-state intramolecular proton transfer (ESIPT) from an amino NH2 group to a carbon atom of an adjacent aromatic ring. The ESIPT mechanisms of 2-(2-aminophenyl)naphthalene are still unclear. Herein, the decay pathways of this molecule in vacuum were investigated by combining static electronic structure calculations and nonadiabatic dynamics simulations. The calculations indicated the existence of two stable structures (S0-1 and S0-2) in the S0 and S1 states. For the S0-1 isomer, upon excitation to the Franck-Condon point, the system relaxed to the S1 minimum quickly, and then there exist four decay pathways (two ESIPT ones and two decay channels with C atom pyramidalization). In the ESIPT decay pathways, the system encounters the S1S0-PT-1 or S1S0-PT-2 conical intersection, which funnels the system rapidly to the S0 state. In the other two pathways, the system de-excited from the S1 to the S0 state via the S1S0-1 or S1S0-2 conical intersection. For the S0-2 structure, the decay pathways were similar to those of S0-1. The dynamics simulations showed that 75 and 69% of trajectories experienced the two ESIPT conical intersections for the S0-1 and S0-2 structures, respectively. Our simulations showed that the lifetime of the S1 state of S0-1 (S0-2) is estimated to be 358 (400) fs. Notably, we not only found the detailed reaction mechanism of the system but also found that the different ground-state configurations of this system have little effect on the reaction mechanism in vacuum.

12.
J Dairy Sci ; 107(6): 3400-3412, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38135045

RESUMO

Hypothyroidism has been found to have an effect on the nutritional composition of human milk during pregnancy. This study aims to explore the combined influence of rheological properties, macronutrient content, particle size, and the zeta potential of milk fat globules, as well as the composition of milk fat globule membrane (MFGM) proteins on the quality of human milk in gestational hypothyroidism. The study revealed that human milk from the group with hypothyroidism during pregnancy (AHM) was less viscoelastic and stable when compared with normal pregnancy group human milk (NHM). Furthermore, the particle size and macronutrient content of NHM were found to be larger than that of AHM. In contrast, the zeta potential of AHM was greater than that of NHM. The sodium dodecyl sulfate-PAGE results disclosed that the composition of MFGM proteins in these 2 groups were generally the same, but the content of AHM was lower than that of NHM. In conclusion, this study confirms that hypothyroidism during pregnancy can have a significant effect on the quality of human milk.


Assuntos
Hipotireoidismo , Leite Humano , Reologia , Feminino , Humanos , Gravidez , Leite Humano/química , Hipotireoidismo/veterinária , Glicolipídeos
13.
J Liposome Res ; 34(1): 124-134, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37555618

RESUMO

Liposomes (LPs) are a delivery system for stabilizing pharmaceuticals with limited use due to their propensity to congregate and fuse. A proposed method of addressing these problems is polymer coating. In this study, the potential of octadecylamine (ODA)-coated liposomes and carboxymethyl chitosan (CMCS/ODA-LPs) for enhancing Wacao pentacyclic triterpene saponin (WPTS) transport capacity was investigated. CMCS/ODA-LPs were produced by electrostatic adsorption and thin-film hydration. Response surface methodology (RSM) was employed to enhance the process and encapsulation efficiency (EE) for optimum drug encapsulation efficiency. The synthesized WPTS-CMCS/ODA-LPs were uniformly dispersed in a circular shape, and during 14 days of storage at 4 °C, the particle size and morphology did not significantly change. Vesicle size, zeta potential, polydispersity index (PDI), and entrapment efficiency (%) were 179.1 ± 7.31 nm, -29.6 ± 1.35 mV, 0.188 ± 0.052, and 75.62 ± 0.43, respectively. The hemolysis test revealed that WPTS-CMCS/ODA-LPs were sufficiently biocompatible. Compared to WPTS-LPs, WPTS-CMCS/ODA-LPs consistently showed a much more significant cytotoxic effect on cancer cells. Early and WPTS-CMCS/ODA-LPs-induced apoptosis resulted in almost seven times more cell death than the control. Compared to physiological pH 7.3, the pH-sensitive CMCS coupled LPs increased drug release at acidic pH 6.5. These findings suggest the efficacy of pH-sensitive CMCS/ODA-LPs as a medication delivery method for WPTS.


Assuntos
Aminas , Antineoplásicos , Quitosana , Lipossomos , Lipopolissacarídeos , Tamanho da Partícula
14.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732816

RESUMO

Target detection technology based on unmanned aerial vehicle (UAV)-derived aerial imagery has been widely applied in the field of forest fire patrol and rescue. However, due to the specificity of UAV platforms, there are still significant issues to be resolved such as severe omission, low detection accuracy, and poor early warning effectiveness. In light of these issues, this paper proposes an improved YOLOX network for the rapid detection of forest fires in images captured by UAVs. Firstly, to enhance the network's feature-extraction capability in complex fire environments, a multi-level-feature-extraction structure, CSP-ML, is designed to improve the algorithm's detection accuracy for small-target fire areas. Additionally, a CBAM attention mechanism is embedded in the neck network to reduce interference caused by background noise and irrelevant information. Secondly, an adaptive-feature-extraction module is introduced in the YOLOX network's feature fusion part to prevent the loss of important feature information during the fusion process, thus enhancing the network's feature-learning capability. Lastly, the CIoU loss function is used to replace the original loss function, to address issues such as excessive optimization of negative samples and poor gradient-descent direction, thereby strengthening the network's effective recognition of positive samples. Experimental results show that the improved YOLOX network has better detection performance, with mAP@50 and mAP@50_95 increasing by 6.4% and 2.17%, respectively, compared to the traditional YOLOX network. In multi-target flame and small-target flame scenarios, the improved YOLO model achieved a mAP of 96.3%, outperforming deep learning algorithms such as FasterRCNN, SSD, and YOLOv5 by 33.5%, 7.7%, and 7%, respectively. It has a lower omission rate and higher detection accuracy, and it is capable of handling small-target detection tasks in complex fire environments. This can provide support for UAV patrol and rescue applications from a high-altitude perspective.

15.
Int J Mol Sci ; 25(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39000025

RESUMO

3,4-disubstituted maleimides find wide applications in various pharmacologically active compounds. This study presents a highly effective approach for synthesizing derivatives of 3,4-disubstituted maleimides through the direct isomerization of α-succinimide-substituted allenoates, followed by a cascade γ'-addition and aryl imines using PR3 as a catalyst. The resulting series of 3,4-disubstituted maleimides exhibited excellent stereoselectivities, achieving yields of up to 86%. To our knowledge, the phosphine-mediated γ'-addition reaction of allenoates is seldom reported.


Assuntos
Iminas , Maleimidas , Fosfinas , Succinimidas , Maleimidas/química , Maleimidas/síntese química , Fosfinas/química , Catálise , Iminas/química , Succinimidas/química , Estereoisomerismo , Estrutura Molecular , Isomerismo
16.
Molecules ; 29(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893468

RESUMO

In this paper, an interesting γ'-carbon 1,6-conjugate addition for phosphine-catalyzed α-succinimide substituted allenoates has been disclosed. A wide array of substrates was found to participate in the reaction, resulting in the production of diverse 4-diarylmethylated 3,4-disubstituted maleimides with satisfactory to outstanding yields. Furthermore, a plausible mechanism for the reaction was proposed by the investigators.

17.
Int Ophthalmol ; 44(1): 166, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557801

RESUMO

PURPOSE: To evaluate the safety and effectiveness of various treatment modalities in patients with diabetic retinopathy (DR) who underwent cataract surgery. METHODS: A comprehensive search for randomized controlled trials (RCTs) was conducted using the PubMed, Embase, Cochrane Library, and CNKI databases up to December 22, 2021. The safety and efficacy of treatment modalities were assessed using the risk ratio (RR) to compare the progression of DR and the mean difference to evaluate the best corrected visual acuity (BCVA) and macular thickness (MT). RESULTS: The meta-analysis of the RCTs revealed that anti-VEGF (anti-vascular endothelial growth factor) drugs significantly reduced the progression of DR [RR: 0.37 (95%CI 0.19, 0.70), P = 0.002] and improved BCVA [mean difference = - 0.06 (- 0.12, - 0.01), P = 0.03] in patients with pre-existing DR who underwent cataract surgery. Steroid drugs also showed a significant reduction in macular thickness [mean difference = - 55.63 (- 90.73, - 20.53), I2 = 56%, P = 0.002] in DR patients two weeks after cataract surgery compared to the control group. The safety profiles of different management options did not differ significantly. CONCLUSION: The present meta-analysis suggests that anti-VEGF drugs can effectively slow down the progression of diabetic retinopathy, improve BCVA, and reduce MT in DR patients who underwent cataract surgery. Steroid drugs also show promise in reducing MT. However, further studies with larger sample sizes are required to compare the efficacy and safety of different management options in a multi-center clinical setting.


Assuntos
Catarata , Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Humanos , Retinopatia Diabética/complicações , Retinopatia Diabética/tratamento farmacológico , Ranibizumab/uso terapêutico , Bevacizumab/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Edema Macular/tratamento farmacológico , Esteroides/uso terapêutico
18.
BMC Bioinformatics ; 24(1): 345, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723425

RESUMO

Understanding gene expression processes necessitates the accurate classification and identification of transcription factors, which is supported by high-throughput sequencing technologies. However, these techniques suffer from inherent limitations such as time consumption and high costs. To address these challenges, the field of bioinformatics has increasingly turned to deep learning technologies for analyzing gene sequences. Nevertheless, the pursuit of improved experimental results has led to the inclusion of numerous complex analysis function modules, resulting in models with a growing number of parameters. To overcome these limitations, it is proposed a novel approach for analyzing DNA transcription factor sequences, which is named as DeepCAC. This method leverages deep convolutional neural networks with a multi-head self-attention mechanism. By employing convolutional neural networks, it can effectively capture local hidden features in the sequences. Simultaneously, the multi-head self-attention mechanism enhances the identification of hidden features with long-distant dependencies. This approach reduces the overall number of parameters in the model while harnessing the computational power of sequence data from multi-head self-attention. Through training with labeled data, experiments demonstrate that this approach significantly improves performance while requiring fewer parameters compared to existing methods. Additionally, the effectiveness of our approach  is validated in accurately predicting DNA transcription factor sequences.


Assuntos
Aprendizado Profundo , Fatores de Transcrição , DNA , Biologia Computacional , Redes Neurais de Computação
19.
BMC Bioinformatics ; 24(1): 473, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097937

RESUMO

PURPOSE: Sequenced Protein-Protein Interaction (PPI) prediction represents a pivotal area of study in biology, playing a crucial role in elucidating the mechanistic underpinnings of diseases and facilitating the design of novel therapeutic interventions. Conventional methods for extracting features through experimental processes have proven to be both costly and exceedingly complex. In light of these challenges, the scientific community has turned to computational approaches, particularly those grounded in deep learning methodologies. Despite the progress achieved by current deep learning technologies, their effectiveness diminishes when applied to larger, unfamiliar datasets. RESULTS: In this study, the paper introduces a novel deep learning framework, termed DL-PPI, for predicting PPIs based on sequence data. The proposed framework comprises two key components aimed at improving the accuracy of feature extraction from individual protein sequences and capturing relationships between proteins in unfamiliar datasets. 1. Protein Node Feature Extraction Module: To enhance the accuracy of feature extraction from individual protein sequences and facilitate the understanding of relationships between proteins in unknown datasets, the paper devised a novel protein node feature extraction module utilizing the Inception method. This module efficiently captures relevant patterns and representations within protein sequences, enabling more informative feature extraction. 2. Feature-Relational Reasoning Network (FRN): In the Global Feature Extraction module of our model, the paper developed a novel FRN that leveraged Graph Neural Networks to determine interactions between pairs of input proteins. The FRN effectively captures the underlying relational information between proteins, contributing to improved PPI predictions. DL-PPI framework demonstrates state-of-the-art performance in the realm of sequence-based PPI prediction.


Assuntos
Aprendizado Profundo , Mapeamento de Interação de Proteínas , Mapeamento de Interação de Proteínas/métodos , Redes Neurais de Computação , Sequência de Aminoácidos , Proteínas/metabolismo
20.
Mol Cancer ; 22(1): 179, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932766

RESUMO

BACKGROUND: Noncoding RNAs such as circular RNAs (circRNAs) are abundant in the human body and influence the occurrence and development of various diseases. Non-small cell lung cancer (NSCLC) is one of the most common malignant cancers. Information on the functions and mechanism of circRNAs in lung cancer is limited; thus, the topic needs more exploration. The purpose of this study was to identify aberrantly expressed circRNAs in lung cancer, unravel their roles in NSCLC progression, and provide new targets for lung cancer diagnosis and therapy. METHODS: High-throughput sequencing was used to analyze differential circRNA expression in patients with lung cancer. qRT‒PCR was used to determine the level of circHERC1 in lung cancer tissues and plasma samples. Gain- and loss-of-function experiments were implemented to observe the impacts of circHERC1 on the growth, invasion, and metastasis of lung cancer cells in vitro and in vivo. Mechanistically, dual luciferase reporter assays, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down experiments were performed to confirm the underlying mechanisms of circHERC1. Nucleocytoplasmic localization of FOXO1 was determined by nucleocytoplasmic isolation and immunofluorescence. The interaction of circHERC1 with FOXO1 was verified by RNA pull-down, RNA immunoprecipitation (RIP) and western blot assays. The proliferation and migration of circHERC1 in vivo were verified by subcutaneous and tail vein injection in nude mice. RESULTS: CircHERC1 was significantly upregulated in lung cancer tissues and cells, ectopic expression of circHERC1 strikingly facilitated the proliferation, invasion and metastasis, and inhibited the apoptosis of lung cancer cells in vitro and in vivo. However, knockdown of circHERC1 exerted the opposite effects. CircHERC1 was mainly distributed in the cytoplasm. Further mechanistic research indicated that circHERC1 acted as a competing endogenous RNA of miR-142-3p to relieve the repressive effect of miR-142-3p on its target HMGB1, activating the MAPK/ERK and NF-κB pathways and promoting cell migration and invasion. More importantly, we found that circHERC1 could bind FOXO1 and sequester it in the cytoplasm, adjusting the feedback AKT pathway. The accumulation of FOXO1 in the cytosol and nuclear exclusion promoted cell proliferation and inhibited apoptosis. CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential prognostic biomarker and therapeutic target for NSCLC. CONCLUSIONS: CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential diagnosis biomarker and therapeutic target for NSCLC. Our findings indicate that circHERC1 facilitates the invasion and metastasis of NSCLC cells by regulating the miR-142-3p/HMGB1 axis and activating the MAPK/ERK and NF-κB pathways. In addition, circHERC1 can promote cell proliferation and inhibit apoptosis by sequestering FOXO1 in the cytoplasm to regulate AKT activity and BIM transcription.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Proteína Forkhead Box O1 , Proteína HMGB1 , Neoplasias Pulmonares , MicroRNAs , RNA Circular , Animais , Humanos , Camundongos , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteína HMGB1/metabolismo , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/genética , Camundongos Nus , MicroRNAs/genética , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Circular/genética , Proteína Forkhead Box O1/metabolismo , Ubiquitina-Proteína Ligases/genética
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