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1.
Ultrasonics ; 145: 107470, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39316886

RESUMO

The low transmission efficiency of ultrasonic waves in waveguides of a high acoustic impedance (referred to as dense materials), due to the impedance mismatch between the background media and the dense materials, poses a significant obstacle to practical applications of high-intensity focused ultrasound (HIFU) such as ultrasound therapy or medical imaging. To address this challenge, we present an inverse optimization scheme for fabrication of novel acoustic meta-lenses, enabling strengthened penetration and enhanced focusing of ultrasonic waves when the waves traverse barriers. Both simulation and experiment validate the effectiveness of the developed meta-lenses which are annexed to hemispherical plates, and demonstrate an enhanced transmission of the sound power by an order of magnitude compared to a scenario without the use of the meta-lens. The focal distance is reconfigurable by adjusting the geometric parameters of the meta-lenses. The proposed design philosophy is not restricted by the complexity of the target structures, and it allows the ultrasonic waves to pass through acoustic barriers with a non-uniform thickness yet maintaining efficient wave focusing. This study holds appealing applications in HIFU-enabled ultrasound imaging and therapy.

2.
Cell Mol Biol Lett ; 29(1): 123, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277732

RESUMO

BACKGROUND: Loss-of-function mutations of ZBTB24 cause immunodeficiency, centromeric instability, and facial anomalies syndrome 2 (ICF2). ICF2 is a rare autosomal recessive disorder with immunological defects in serum antibodies and circulating memory B cells, resulting in recurrent and sometimes fatal respiratory and gastrointestinal infections. The genotype-phenotype correlation in patients with ICF2 indicates an essential role of ZBTB24 in the terminal differentiation of B cells. METHODS: We used the clustered regularly interspaced short palindromic repeats (CRISPER)/Cas9 technology to generate B cell specific Zbtb24-deficient mice and verified the deletion specificity and efficiency by quantitative polymerase chain reaction (Q-PCR) and western blotting analyses in fluorescence-activated cell sorting (FACS)-sorted cells. The development, phenotype of B cells and in vivo responses to T cell dependent or independent antigens post immunization were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Adoptive transfer experiment in combination with in vitro cultures of FACS-purified B cells and RNA-Seq analysis were utilized to specifically determine the impact of Zbtb24 on B cell biology as well as the underlying mechanisms. RESULTS: Zbtb24 is dispensable for B cell development and maintenance in naive mice. Surprisingly, B cell specific deletion of Zbtb24 does not evidently compromise germinal center reactions and the resulting primary and secondary antibody responses induced by T cell dependent antigens (TD-Ags), but significantly inhibits T cell independent antigen-elicited antibody productions in vivo. At the cellular level, Zbtb24-deficiency specifically impedes the plasma cell differentiation of B1 cells without impairing their survival, activation and proliferation in vitro. Mechanistically, Zbtb24-ablation attenuates heme biosynthesis partially through mTORC1 in B1 cells, and addition of exogenous hemin abrogates the differentiation defects of Zbtb24-null B1 cells. CONCLUSIONS: Zbtb24 seems to regulate antibody responses against TD-Ags B cell extrinsically, but it specifically promotes the plasma cell differentiation of B1 cells via heme synthesis in mice. Our study also suggests that defected B1 functions contribute to recurrent infections in patients with ICF2.


Assuntos
Diferenciação Celular , Doenças da Imunodeficiência Primária , Fatores de Transcrição , Animais , Camundongos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Face/anormalidades , Síndromes de Imunodeficiência/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças da Imunodeficiência Primária/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
3.
Rep Prog Phys ; 87(9)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39121866

RESUMO

Topological Anderson phases (TAPs) offer intriguing transitions from ordered to disordered systems in photonics and acoustics. However, achieving these transitions often involves cumbersome structural modifications to introduce disorders in parameters, leading to limitations in flexible tuning of topological properties and real-space control of TAPs. Here, we exploit disordered convective perturbations in a fixed heat transport system. Continuously tunable disorder-topology interactions are enabled in thermal dissipation through irregular convective lattices. In the presence of a weak convective disorder, the trivial diffusive system undergos TAP transition, characterized by the emergence of topologically protected corner modes. Further increasing the strength of convective perturbations, a second phase transition occurs converting from TAP to Anderson phase. Our work elucidates the pivotal role of disorders in topological heat transport and provides a novel recipe for manipulating thermal behaviors in diverse topological platforms.

4.
Biomimetics (Basel) ; 9(8)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39194431

RESUMO

Biomimetic robotic fish are a novel approach to studying quiet, highly agile, and efficient underwater propulsion systems, attracting significant interest from experts in robotics and engineering. These versatile robots showcase their ability to operate effectively in various water conditions. Nevertheless, the comprehension of the swimming mechanics and the evolution of the flow field of flexible robots in counterflow regions is still unknown. This paper presents a framework for the self-propulsion of robotic fish that imitates biological characteristics. The method utilizes computational fluid dynamics to analyze the hydrodynamic efficiency of the organisms at different frequencies of tail movement, under both still and opposing flow circumstances. Moreover, this study clarifies the mechanisms that explain how changes in the aquatic environment affect the speed and efficiency of propulsion. It also examines the most effective swimming tactics for places with counterflow. The results suggest that the propulsion effectiveness of robotic fish in counterflow locations does not consistently correspond to various tail-beat frequencies. By utilizing vorticity maps, a comparative analysis can identify situations when counterflow zones improve the efficiency of propulsion.

5.
Front Physiol ; 15: 1451556, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39210968

RESUMO

Purpose: To investigate the effects of transcranial direct current stimulation (tDCS) combined with Bosu ball training on the injury potential during drop landing in people with chronic ankle instability (CAI). Methods: A total of 40 participants with CAI were recruited and randomly divided into the tDCS + Bosu and Bosu groups. The people in the tDCS + Bosu group received intervention of tDCS combined with Bosu ball training, and those in the Bosu group received intervention of sham tDCS and Bosu ball training, for 6 weeks with three 20-min sessions per week. Before (week0) and after (week7) the intervention, all participants drop-landed on a trap-door device, with their affected limbs on a moveable platform, which could be flipped 24° inward and 15° forward to mimic an ankle inversion condition. The kinematic data were captured using a twelve-camera motion capture system. Two-way ANOVA with repeated measures was used to analyze data. Results: Significant group-by-intervention interactions were detected in the peak ankle inversion angular velocity (p = 0.047, η2 p = 0.118), the time to peak ankle inversion (p = 0.030, η2 p = 0.139), and the plantarflexion angle at the moment of peak ankle inversion (p = 0.014, η2 p = 0.173). Post hoc comparisons showed that compared with week0, the peak ankle inversion angular velocity and the plantarflexion angle at the moment of peak ankle inversion were reduced, the time to peak ankle inversion was advanced in both groups at week7, and the changes were greater in the tDCS + Bosu group compared to the Bosu group. And, a significant intervention main effect was detected in the peak ankle inversion angle in the two groups (p < 0.001, η2 p = 0.337). Conclusion: Compared with the Bosu ball training, the tDCS combined with Bosu ball training was more effective in reducing the injury potential during drop landing in people with CAI.

6.
BMJ Open Diabetes Res Care ; 12(3)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834334

RESUMO

INTRODUCTION: None of the studies of type 2 diabetes (T2D) subtyping to date have used linked population-level data for incident and prevalent T2D, incorporating a diverse set of variables, explainable methods for cluster characterization, or adhered to an established framework. We aimed to develop and validate machine learning (ML)-informed subtypes for type 2 diabetes mellitus (T2D) using nationally representative data. RESEARCH DESIGN AND METHODS: In population-based electronic health records (2006-2020; Clinical Practice Research Datalink) in individuals ≥18 years with incident T2D (n=420 448), we included factors (n=3787), including demography, history, examination, biomarkers and medications. Using a published framework, we identified subtypes through nine unsupervised ML methods (K-means, K-means++, K-mode, K-prototype, mini-batch, agglomerative hierarchical clustering, Birch, Gaussian mixture models, and consensus clustering). We characterized clusters using intracluster distributions and explainable artificial intelligence (AI) techniques. We evaluated subtypes for (1) internal validity (within dataset; across methods); (2) prognostic validity (prediction for 5-year all-cause mortality, hospitalization and new chronic diseases); and (3) medication burden. RESULTS: Development: We identified four T2D subtypes: metabolic, early onset, late onset and cardiometabolic. Internal validity: Subtypes were predicted with high accuracy (F1 score >0.98). Prognostic validity: 5-year all-cause mortality, hospitalization, new chronic disease incidence and medication burden differed across T2D subtypes. Compared with the metabolic subtype, 5-year risks of mortality and hospitalization in incident T2D were highest in late-onset subtype (HR 1.95, 1.85-2.05 and 1.66, 1.58-1.75) and lowest in early-onset subtype (1.18, 1.11-1.27 and 0.85, 0.80-0.90). Incidence of chronic diseases was highest in late-onset subtype and lowest in early-onset subtype. Medications: Compared with the metabolic subtype, after adjusting for age, sex, and pre-T2D medications, late-onset subtype (1.31, 1.28-1.35) and early-onset subtype (0.83, 0.81-0.85) were most and least likely, respectively, to be prescribed medications within 5 years following T2D onset. CONCLUSIONS: In the largest study using ML to date in incident T2D, we identified four distinct subtypes, with potential future implications for etiology, therapeutics, and risk prediction.


Assuntos
Diabetes Mellitus Tipo 2 , Registros Eletrônicos de Saúde , Aprendizado de Máquina , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Masculino , Pessoa de Meia-Idade , Prognóstico , Idoso , Adulto , Hipoglicemiantes/uso terapêutico , Incidência , Seguimentos
7.
ACS Pharmacol Transl Sci ; 7(6): 1711-1721, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38898948

RESUMO

Despite the long-standing availability of effective prophylaxis, chronic hepatitis B virus (HBV) infection remains a formidable public health threat. Antiviral treatments can limit viral propagation, but prolonged therapy is necessary to control HBV replication. Robust in vitro models of HBV infection are indispensable prerequisites for elucidating viral pathogenesis, delineating virus-host interplay and developing novel therapeutic, preventative countermeasures. Buoyed by advances in molecular techniques and tissue culture systems, investigators have engineered numerous in vitro models of the HBV life cycle. However, all current platforms harbor limitations in the recapitulation of natural infection. In this article, we comprehensively review the HBV life cycle, provide an overview of existing in vitro HBV infection and replication systems, and succinctly present the benefits and caveats in each model with the primary objective of constructing refined experimental models that closely mimic native viral infection and offering robust support for the ambitious "elimination of hepatitis by 2030" initiative.

8.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1044-1054, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38884239

RESUMO

Aiming to understand the responses of soil seed bank to different water levels, we investigated vegetation and soil seed bank along a water level gradient (frequently flooded area, unflooded area) on the floodplain wetland of Juzhang River. We used the structural equation model to explore the direct and indirect effects of water level on soil seed bank, and used non-metric multidimensional scaling (NMDS) to assess the role of soil seed bank for vegetation regeneration. The results showed that the density of transient and persistent seed banks at unflooded area was 36.9% and 7.8% higher than that of frequently flooded area, respectively. Shannon index and Pielou index of seed bank and vegetation were significantly affected by water level and sampling location. Water level significantly affected the similarity between seed bank and aboveground vegetation, and the similarity of persistent seed bank with aboveground vegetation was significantly higher than that with transient seed bank. Structural equation model showed that water level had a direct effect on seed bank density, and indirect effects on density and richness of seed bank via affecting soil pH and NH4+-N content. NMDS results showed that there was no significant difference in the composition of the persistent seed bank and vegetation community in autumn under different water levels, but water level significantly changed the community composition of transient seed bank. Transient seed bank was affected by the vegetation and soil property, while persistent seed bank was determined by aboveground vegetation and water level. Although soil seed bank had low regeneration potential for the vegetation communities in floodplain wetlands, soil seed bank could not be neglected during the restoration of propagule diversity after disturbance in wetlands. Persistent seed bank would be an importance source of diversity of propagules for floodplain wetlands restoration following disturbance.


Assuntos
Rios , Solo , Áreas Alagadas , China , Solo/química , Inundações , Conservação dos Recursos Naturais , Sementes/crescimento & desenvolvimento , Ecossistema , Movimentos da Água , Banco de Sementes
9.
Front Public Health ; 12: 1404819, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919922

RESUMO

Objective: To investigate parental knowledge, attitudes, and practices (KAP) toward adolescent depression. Methods: A cross-sectional survey was conducted between October 2022 and October 2023 at The First Affiliated Hospital of Ningbo University among parents of adolescents diagnosed with depression. A self-administered questionnaire was used to collect the parents' demographic characteristics and KAP toward adolescent depression. Results: A total of 522 questionnaires were collected from parents of depressed adolescents. Among the participants, 383 (73.37%) were female. In addition, 426 participants (81.61%) had children aged 14-18. The mean knowledge, attitude, and practice scores were 9.09 ± 2.37 (possible range: 0-12), 37.04 ± 4.11 (possible range: 11-55), and 31.53 ± 3.84 (possible range: 8-40), respectively. There were significant positive correlations between knowledge and attitude (r = 0.225, p < 0.001), knowledge and practice (r = 0.240, p < 0.001), and attitude and practice (r = 0.381, p < 0.001). The path analysis showed significant direct effects of knowledge on attitude (ß = 0.422, p < 0.001) and practice (ß = 0.283, p < 0.001). There was an indirect effect of knowledge on practice through attitude (ß = 0.131, p = 0.004). Attitude directly impacted practice (ß = 0.311, p < 0.001). Conclusion: Parents of adolescents diagnosed with depression exhibited moderate KAP regarding adolescent depression. The study underscored the importance of targeted interventions to improve parental KAP in supporting adolescents with depression. Moreover, future research should explore additional factors influencing parental attitudes and behaviors toward adolescent depression to develop more effective interventions.


Assuntos
Depressão , Conhecimentos, Atitudes e Prática em Saúde , Pais , Humanos , Feminino , Masculino , Adolescente , Estudos Transversais , China , Pais/psicologia , Inquéritos e Questionários , Depressão/psicologia , Adulto , Pessoa de Meia-Idade
10.
Mol Plant ; 17(8): 1204-1220, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38894538

RESUMO

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the environment. Among these processes, the floral transition is essential to ensure reproductive success and is finely regulated by several internal and external genetic networks. The photoperiodic pathway, which controls plant response to day length, is one of the most important pathways controlling flowering. In Arabidopsis photoperiodic flowering, CONSTANS (CO) is the central gene activating the expression of the florigen FLOWERING LOCUS T (FT) in the leaves at the end of a long day. The circadian clock strongly regulates CO expression. However, to date, no evidence has been reported regarding a feedback loop from the photoperiod pathway back to the circadian clock. Using transcriptional networks, we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod pathway. Gene expression, chromatin immunoprecipitation experiments, and phenotypic analysis allowed us to elucidate the role of CO over the circadian clock. Plants with altered CO expression showed a different internal clock period, measured by daily leaf rhythmic movements. We showed that CO upregulates the expression of key genes related to the circadian clock, such as CCA1, LHY, PRR5, and GI, at the end of a long day by binding to specific sites on their promoters. Moreover, a high number of PRR5-repressed target genes are upregulated by CO, and this could explain the phase transition promoted by CO. The CO-PRR5 complex interacts with the bZIP transcription factor HY5 and helps to localize the complex in the promoters of clock genes. Taken together, our results indicate that there may be a feedback loop in which CO communicates back to the circadian clock, providing seasonal information to the circadian system.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Relógios Circadianos , Proteínas de Ligação a DNA , Regulação da Expressão Gênica de Plantas , Fotoperíodo , Fatores de Transcrição , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Relógios Circadianos/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Flores/genética , Flores/fisiologia
11.
Biomimetics (Basel) ; 9(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38667232

RESUMO

Precision control of multiple robotic fish visual navigation in complex underwater environments has long been a challenging issue in the field of underwater robotics. To address this problem, this paper proposes a multi-robot fish obstacle traversal technique based on the combination of cross-modal variational autoencoder (CM-VAE) and imitation learning. Firstly, the overall framework of the robotic fish control system is introduced, where the first-person view of the robotic fish is encoded into a low-dimensional latent space using CM-VAE, and then different latent features in the space are mapped to the velocity commands of the robotic fish through imitation learning. Finally, to validate the effectiveness of the proposed method, experiments are conducted on linear, S-shaped, and circular gate frame trajectories with both single and multiple robotic fish. Analysis reveals that the visual navigation method proposed in this paper can stably traverse various types of gate frame trajectories. Compared to end-to-end learning and purely unsupervised image reconstruction, the proposed control strategy demonstrates superior performance, offering a new solution for the intelligent navigation of robotic fish in complex environments.

12.
Chemistry ; 30(25): e202401026, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38607283

RESUMO

Invited for the cover of this issue is the group of Long Pan and co-workers at Asymchem Life Sciences (Tianjin) Co. Ltd. The image depicts a novel continuous process for the synthesis of a macrocyclic poly(ethylene glycol) (PEG) sulfite, the precursor to PEG macrocyclic sulfate, a useful building block in PEG chemistry. Read the full text of the article at 10.1002/chem.202304319.

13.
Emerg Microbes Infect ; 13(1): 2350164, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38687697

RESUMO

Vibrio alginolyticus, an emergent species of Vibrio genus, exists in aquatic and marine environments. It has undergone genetic diversification, but its detailed genomic diversity is still unclear. Here, we performed a multi-dimensional comparative genomic analysis to explore the population phylogeny, virulence-related genes and potential drug resistance genes of 184 V. alginolyticus isolates. Although genetic diversity is complex, we analysed the population structure using three sub-datasets, including the subdivision for three lineages into sublineages and the distribution of strains in the marine ecological niche. Accessory genes, most of which reclassified V. alginolyticus genomes as different but with relatively close affinities, were nonuniformly distributed among these isolates. We demonstrated that the spread of some post-evolutionary isolates (mainly L3 strains isolated from Chinese territorial seas) was likely to be closely related to human activities, whereas other more ancestral strains (strains in the L1 and L2) tended to be locally endemic and formed clonal complex groups. In terms of pathogenicity, the potential virulence factors were mainly associated with toxin, adherence, motility, chemotaxis, and the type III secretion system (T3SS). We also found five types of antibacterial drug resistance genes. The prevalence of ß-lactam resistance genes was 100%, which indicated that there may be a potential risk of natural resistance to ß-lactam drugs. Our study reveals insights into genomic characteristics, evolution and potential virulence-associated gene profiles of V. alginolyticus.


Assuntos
Evolução Molecular , Genoma Bacteriano , Filogenia , Vibrioses , Vibrio alginolyticus , Fatores de Virulência , Vibrio alginolyticus/genética , Vibrio alginolyticus/patogenicidade , Vibrio alginolyticus/classificação , Vibrio alginolyticus/efeitos dos fármacos , Fatores de Virulência/genética , Virulência/genética , Vibrioses/microbiologia , Variação Genética , Humanos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Animais
14.
Nutrients ; 16(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38474727

RESUMO

Hepatocellular carcinoma (HCC), being ranked as the top fifth most prevalent cancer globally, poses a significant health challenge, with a considerable mortality rate. Hepatitis B virus (HBV) infection stands as the primary factor contributing to HCC, presenting substantial challenges in its treatment. This study aimed to identify lactic acid bacteria (LAB) with anti-HBV properties and evaluate their impact on the intestinal flora in HBV-associated HCC. Initially, two LAB strains, Levilactobacillus brevis SR52-2 (L. brevis SR52-2) and LeviLactobacillus delbrueckii subsp. bulgaicus Q80 (L. delbrueckii Q80), exhibiting anti-HBV effects, were screened in vitro from a pool of 498 LAB strains through cell experiments, with extracellular expression levels of 0.58 ± 0.05 and 0.65 ± 0.03, respectively. These strains exhibited the capability of inhibiting the expression of HBeAg and HBsAg. Subsequent in vitro fermentation, conducted under simulated anaerobic conditions mimicking the colon environment, revealed a decrease in pH levels in both the health control (HC) and HCC groups influenced by LAB, with a more pronounced effect observed in the HC group. Additionally, the density of total short-chain fatty acids (SCFAs) significantly increased (p < 0.05) in the HCC group. Analysis of 16S rRNA highlighted differences in the gut microbiota (GM) community structure in cultures treated with L. brevis SR52-2 and L. delbrueckii Q80. Fecal microflora in normal samples exhibited greater diversity compared to HBV-HCC samples. The HCC group treated with LAB showed a significant increase in the abundance of the phyla Firmicutes, Bacteroidetes and Actinobacteria, while Proteobacteria significantly decreased compared to the untreated HCC group after 48 h. In conclusion, the findings indicate that LAB, specifically L. brevis SR52-2 and L. delbrueckii Q80, possessing antiviral properties, contribute to an improvement in gastrointestinal health.


Assuntos
Carcinoma Hepatocelular , Microbioma Gastrointestinal , Hepatite B Crônica , Hepatite B , Lactobacillales , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/complicações , Vírus da Hepatite B/genética , RNA Ribossômico 16S , Anticorpos
15.
Chemistry ; 30(25): e202304319, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38277192

RESUMO

Many macrocyclic compounds are attractive drug-like molecules or intermediates due to their special properties. However, the bulk synthesis of such compounds are hindered by the necessity of using diluted solutions, in order to prevent intermolecular reactions that yields oligomer impurities, thereby resulting in a low production efficiency. Such challenge can be adequately addressed by using continuous reactors, allowing improved efficiency with smaller space footprints. In this work, we proposed a novel continuous process for the synthesis of a macrocyclic sulfite of tetraethylene glycol (PEG4-MCSi), which is a precursor to a very useful building block, PEG4-macrocyclic sulfate (PEG4-MCS). The basic reaction parameters, including stoichiometry and temperature, were first confirmed with small batch reactions, and the effectiveness of coiled reactors and continuous stirred tank reactors (CSTRs) were compared. Cascaded CSTRs were proven to be suitable, and the reaction parameters were subject to further optimization to give a robust continuous process. The process was then tested with 4 parallel runs for up to 64 h. Finally, the merits and demerits of batch and continuous reactions were also compared, demonstrating the suitability of latter in the bulk production of macrocyclic PEG-MCSi compounds.

16.
Sci Total Environ ; 917: 170547, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38296097

RESUMO

Microplastics (MPs) transfer from the environment to living organisms is a nonignorable global problem. As a complete metamorphosis insect, the larvae and adult Culex quinquefasciatus mosquito live in aquatic and terrestrial environments, respectively, where they easily access MPs. However, little is known about mosquitoes' potential role in MPs accumulation throughout ecosystems. Therefore, we conducted a study with different MPs particle sizes (0.1/1/10 µm) and concentrations (0.5/5/50 µg/mL) on Cx. quinquefasciatus to address this issue. Once exposed at the young larval stage, MPs could accompany the mosquitoes their entire life. The fluorescence signals of MPs in the larvae were mainly located in the intestines. Its intensity increased (from 3.72 × 106 AU to 5.45 × 107 AU) as the concentrations of MPs increases. The fluorescence signals of MPs were also detected in the blood and skin tissues of mice bitten by adult mosquitoes with MPs containing in their bodies. Mosquitos exposed to MPs showed longer larval pupation and eclosion time as well as lower adult body weight. In addition, MPs significantly reduced the lethal effect of pyrethroid insecticides (97.77 % vs. 48.88 %, p < 0.05) with 15.1 % removal of the deltamethrin concentration. After MPs exposure, the relative abundance of the Cx. quinquefasciatus gut microbiome, such as Wolbachia spp., Elizabethkingia spp., and Asaia spp., changed as the MPs size and concentration changes. Mosquitoes provide a new pathway for MPs accumulation and transfer to higher-level living organisms. Moreover, MPs significantly reduce the control effect of deltamethrin, providing new guidelines for mosquito insecticide application in MPs contamination circumstances.


Assuntos
Culex , Mordeduras e Picadas de Insetos , Inseticidas , Nitrilas , Piretrinas , Animais , Camundongos , Microplásticos , Plásticos , Ecossistema , Inseticidas/toxicidade , Larva , Mamíferos , Controle de Mosquitos
17.
Drug Resist Updat ; 73: 101036, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38183874

RESUMO

BACKGROUND: Extended-spectrum ß-lactamases (ESBLs) producing bacteria have spread worldwide and become a global public health concern. Plasmid-mediated transfer of ESBLs is an important route for resistance acquisition. METHODS: We collected 1345 complete sequences of plasmids containing CTX-Ms from public database. The global transmission pattern of plasmids and evolutionary dynamics of CTX-Ms have been inferred. We applied the pan-genome clustering based on plasmid genomes and evolution analysis to demonstrate the transmission events. FINDINGS: Totally, 48 CTX-Ms genotypes and 186 incompatible types of plasmids were identified. The geographical distribution of CTX-Ms showed significant differences across countries and continents. CTX-M-14 and CTX-M-55 were found to be the dominant genotypes in Asia, while CTX-M-1 played a leading role in Europe. The plasmids can be divided into 12 lineages, some of which forming distinct geographical clusters in Asia and Europe, while others forming hybrid populations. The Inc types of plasmids are lineage-specific, with the CTX-M-1_IncI1-I (Alpha) and CTX-M-65_IncFII (pHN7A8)/R being the dominant patterns of cross-host and cross-regional transmission. The IncI-I (Alpha) plasmids with the highest number, were presumed to form communication groups in Europe-Asia and Asia-America-Oceania, showing the transmission model as global dissemination and regional microevolution. Meanwhile, the main kinetic elements of blaCTX-Ms showed genotypic preferences. ISEcpl and IS26 were most frequently involved in the transfer of CTX-M-14 and CTX-M-65, respectively. IS15 has become a crucial participant in mediating the dissemination of blaCTX-Ms. Interestingly, blaTEM and blaCTX-Ms often coexisted in the same transposable unit. Furthermore, antibiotic resistance genes associated with aminoglycosides, sulfonamides and cephalosporins showed a relatively high frequency of synergistic effects with CTX-Ms. CONCLUSIONS: We recognized the dominant blaCTX-Ms and mainstream plasmids of different continents. The results of this study provide support for a more effective response to the risks associated with the evolution of blaCTX-Ms-bearing plasmids, and lay the foundation for genotype-specific epidemiological surveillance of resistance, which are of important public health implications.


Assuntos
Antibacterianos , Escherichia coli , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , beta-Lactamases/genética , Escherichia coli/genética , Genômica , Plasmídeos/genética
18.
J Glob Antimicrob Resist ; 36: 181-187, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38072240

RESUMO

OBJECTIVES: Recently, blaCTX-Ms have become the dominant ESBLs for E. coli strains worldwide. We aim to provide a systematic study on the relationships between sequence types (STs), clinical origins, and the blaCTX-Ms genotypes of E. coli strains. METHODS: Totally, 1005 complete sequences of clinical E. coli were collected from NCBI. Multilocus sequence typing (MLST) and antibiotic resistance genes screening were performed. RESULTS: Faeces (26.27%), urine (16.02%), and blood (8.26%) were shown to be the main sources of clinical E. coli isolates. The isolates belong to 153 STs and 26 clonal complexes (CCs). The most prevalent STs were ST2 (11.3%), ST43 (8.6%), and ST8 (5.7%). The positive rate for blaCTX-Ms was 34.7%. Different samples showed significantly different blaCTX-Ms positive rates (P<0.05). The main genotypes were blaCTX-M-55-like (47.6%), blaCTX-M-1-like (31.8%), and blaCTX-M-2-like (22.1%). The majority of ST2 strains had blaCTX-M-55-like genes. In ST8 strains, there was a homogeneous distribution of blaCTX-M-9, blaCTX-M-65, blaCTX-M-55, blaCTX-M-2, and blaCTX-M-1. Only ST43 strains exhibited the presence of blaCTX-M-79. The blaCTX-Ms showed a pattern of cross-continental transmission with intra-regional spread. Among the 349 blaCTX-Ms-producing E. coli strains, 148 strains also carried carbapenem resistance genes, including blaNDM (119, 34.1%), blaKPC (16, 4.6%), blaOXA-48 (9, 2.6%) and blaIMP (4, 1.1%). Also, 81 strains carried the mcr gene (23.2%). CONCLUSIONS: E. coli has become increasingly rich in blaCTX-Ms genotypes. Our findings about the connection between E. coli STs and blaCTX-Ms can be utilized to identify E. coli strains with high potential to spread drug resistance in the future.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Humanos , Escherichia coli , Proteínas de Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Tipagem de Sequências Multilocus , Proteína 1 Semelhante a Receptor de Interleucina-1/genética
19.
Chinese Medical Journal ; (24): 105-114, 2024.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1007746

RESUMO

BACKGROUND@#Triple-negative breast cancer (TNBC) is a type of highly invasive breast cancer with a poor prognosis. According to new research, long noncoding RNAs (lncRNAs) play a significant role in the progression of cancer. Although the role of lncRNAs in breast cancer has been well reported, few studies have focused on TNBC. This study aimed to explore the biological function and clinical significance of forkhead box C1 promoter upstream transcript (FOXCUT) in triple-negative breast cancer.@*METHODS@#Based on a bioinformatic analysis of the cancer genome atlas (TCGA) database, we detected that the lncRNA FOXCUT was overexpressed in TNBC tissues, which was further validated in an external cohort of tissues from the General Surgery Department of the First Affiliated Hospital of Nanjing Medical University. The functions of FOXCUT in proliferation, migration, and invasion were detected in vitro or in vivo. Luciferase assays and RNA immunoprecipitation (RIP) were performed to reveal that FOXCUT acted as a competitive endogenous RNA (ceRNA) for the microRNA miR-24-3p and consequently inhibited the degradation of p38.@*RESULTS@#lncRNA FOXCUT was markedly highly expressed in breast cancer, which was associated with poor prognosis in some cases. Knockdown of FOXCUT significantly inhibited cancer growth and metastasis in vitro or in vivo. Mechanistically, FOXCUT competitively bounded to miR-24-3p to prevent the degradation of p38, which might act as an oncogene in breast cancer.@*CONCLUSION@#Collectively, this research revealed a novel FOXCUT/miR-24-3p/p38 axis that affected breast cancer progression and suggested that the lncRNA FOXCUT could be a diagnostic marker and therapeutic target for breast cancer.


Assuntos
Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , RNA Longo não Codificante/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
20.
Microorganisms ; 11(12)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38137980

RESUMO

A rising incidence of clinical infections has been caused by Kluyvera, a significant opportunistic pathogen. Meanwhile, Kluyvera acts as an important reservoir of blaCTX-Ms, which are the dominant genes of class A extended-spectrum ß-lactamases (ESBLs). In this work, 60 strains of Kluyvera were subjected to phylogenetic relationship reconstruction, antimicrobial susceptibility testing, and antibiotic resistance genes prediction. All mature blaCTX-Ms were gathered to perform subgroup reclassification. The findings demonstrate that Kluyvera has a large gene pool with significant genetic flexibility. Notably, 25% of strains showed simultaneous detection of ESBLs and carbapenem resistance genes. The genotypes of fourteen novel blaCTX-Ms were identified. A new subgroup classification approach for blaCTX-Ms was defined by using 20 amino acid site variants, which could split blaCTX-Ms into 10 subgroups. The results of the subgroup division were consistent with the phylogenetic clustering. More significantly, we proposed a novel blaCTX-M subgroup, KLUS, that is chromosomally encoded in K. sichuanensis and the new species put forward in this study, showing amino acid differences from the currently known sequences. Cloning and transformation tests demonstrated that the recipient bacteria had a robust phenotype of cefotaxime resistance. Closely related Kluyvera species had blaCTX-Ms in the same subgroup. Our research lays the groundwork for a deeper comprehension of Kluyvera and emphasizes how important a blaCTX-M reservoir it is. We provide an update on blaCTX-M subgroups reclassification from the aspects of phylogenetic relationship, amino acid differences, and the new subgroup KLUS, which needs to be strengthen monitored due to its strong resistance phenotype to cefotaxime.

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