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1.
Adv Sci (Weinh) ; : e2310068, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477427

RESUMO

The impact of external factors on the human gut microbiota and how gut microbes contribute to human health is an intriguing question. Here, the gut microbiome of 3,224 individuals (496 with serum metabolome) with 109 variables is studied. Multiple analyses reveal that geographic factors explain the greatest variance of the gut microbiome and the similarity of individuals' gut microbiome is negatively correlated with their geographic distance. Main food components are the most important factors that mediate the impact of host habitats on the gut microbiome. Diet and gut microbes collaboratively contribute to the variation of serum metabolites, and correlate to the increase or decrease of certain clinical indexes. Specifically, systolic blood pressure is lowered by vegetable oil through increasing the abundance of Blautia and reducing the serum level of 1-palmitoyl-2-palmitoleoyl-GPC (16:0/16:1), but it is reduced by fruit intake through increasing the serum level of Blautia improved threonate. Besides, aging-related clinical indexes are also closely correlated with the variation of gut microbes and serum metabolites. In this study, the linkages of geographic locations, diet, the gut microbiome, serum metabolites, and physiological indexes in a Chinese population are characterized. It is proved again that gut microbes and their metabolites are important media for external factors to affect human health.

2.
Nanomaterials (Basel) ; 14(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535704

RESUMO

The 8-16-4 graphyne, a recently identified two-dimensional carbon allotrope, exhibits distinctive mechanical and electrical properties, making it a candidate material for flexible electronic applications. This study endeavors to enhance our comprehension of the fracture behavior and mechanical properties of 8-16-4 graphyne. The mechanical properties of 8-16-4 graphyne were evaluated through molecular dynamics simulations, examining the impact of boundary conditions, temperature, and strain rate, as well as the coupled interactions between temperature, vacancy defects, and microcracks. The findings reveal that 8-16-4 graphyne undergoes fracture via the cleavage of ethylene bonds at a critical strain value of approximately 0.29. Variations in boundary conditions and strain rate influence the fidelity of tensile simulation outcomes. Temperature, vacancy concentration, and the presence of microcracks markedly affect the mechanical properties of 8-16-4 graphyne. In contrast to other carbon allotropes, 8-16-4 graphyne exhibits a diminished sensitivity to vacancy defects in its mechanical performance. However, carbon vacancies at particular sites are more prone to initiating cracks. Furthermore, pre-existing microcracks within the material can potentially alter the fracture mode.

3.
NPJ Precis Oncol ; 8(1): 76, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538739

RESUMO

Diffuse large B cell lymphoma (DLBCL) is an aggressive blood cancer known for its rapid progression and high incidence. The growing use of immunohistochemistry (IHC) has significantly contributed to the detailed cell characterization, thereby playing a crucial role in guiding treatment strategies for DLBCL. In this study, we developed an AI-based image analysis approach for assessing PD-L1 expression in DLBCL patients. PD-L1 expression represents as a major biomarker for screening patients who can benefit from targeted immunotherapy interventions. In particular, we performed large-scale cell annotations in IHC slides, encompassing over 5101 tissue regions and 146,439 live cells. Extensive experiments in primary and validation cohorts demonstrated the defined quantitative rule helped overcome the difficulty of identifying specific cell types. In assessing data obtained from fine needle biopsies, experiments revealed that there was a higher level of agreement in the quantitative results between Artificial Intelligence (AI) algorithms and pathologists, as well as among pathologists themselves, in comparison to the data obtained from surgical specimens. We highlight that the AI-enabled analytics enhance the objectivity and interpretability of PD-L1 quantification to improve the targeted immunotherapy development in DLBCL patients.

4.
Wei Sheng Yan Jiu ; 53(1): 14-65, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38443168

RESUMO

OBJECTIVE: To analyze the generational differences in overweight/obesity prevalence and central obesity prevalence among Chinese adult residents aged 20 years and above at the same ages. METHODS: A total of 38 908 healthy adult residents aged 20 years and above from "the China Health and Nutrition Survey" in 1991, 2000, 2009, and 2018 were selected for this study. Based on age at the time of the survey, the study subjects were divided into 6 age groups(20-29, 30-39, 40-49, 50-59, 60-69, and ≥70 years old) corresponding to 9 different generations of births in 10, 20, 30, 40, 50, 60, 70, 80, and 90 generations, respectively. All analyses were stratified by sex. A chi-square test was used to compare generational differences in overweight/obesity and central obesity at similar ages in populations born in different generations. Non-parametric tests were used to compare generational differences in BMI and waist circumference. RESULTS: (1) Body mass index(BMI), overweight/obesity rate, waist circumference, and central obesity rate showed unfavorable generational differences(P<0.0001) among different generations of residents at similar ages. BMI, overweight/obesity prevalence, waist circumference, and central obesity prevalence were higher in the younger generation. Overweight/obesity and central obesity occurred at an earlier age in the younger generation. (2) Generational differences in overweight/obesity rates and central obesity rates followed gender specificity. Unfavorable generational differences(P<0.0001) occurred in overweight/obesity as well as central obesity between the two oldest generations of females, with maximum differences of 15.5% and 8.0%. Unfavorable generational differences(P<0.0001) occurred in overweight/obesity between the two adjacent generations of men and in central obesity between the two youngest generations of men, with maximum differences of 19.5% and 17.0%. CONCLUSION: The prevalence of overweight/obesity and central obesity among Chinese adults showed unfavorable generational differences. The prevalence of overweight/obesity and central obesity was higher in the younger generation. The younger generation develops overweight/obesity at an earlier age.


Assuntos
Obesidade Abdominal , Sobrepeso , Adulto , Idoso , Feminino , Humanos , Masculino , Povo Asiático/genética , China/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adulto Jovem , Pessoa de Meia-Idade
5.
Sci Total Environ ; 923: 171560, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38458455

RESUMO

Carbapenem-resistant Klebsiella aerogenes (CRKA), being one of the members of carbapenem-resistant Enterobacteriaceae (CRE), has caused great public health concern, but with fewer studies compared to other CRE members. Furthermore, studies on phylogenetic analysis based on whole genome Single-Nucleotide Polymorphism (SNP) of CRKA were limited. Here, 20 CRKA isolates (11 blaKPC-2-bearing and 9 blaNDM-1/5-harboring) were characterized by antimicrobial susceptibility testing, conjugation assay, whole genome sequencing (WGS) and bioinformatics analysis. Additionally, the phylogeographic relationships of K. aerogenes were further investigated from public databases. All isolates were multidrug-resistant (MDR) bacteria, and they demonstrated susceptibility to colistin. Most blaKPC-2 or blaNDM-1/5-carrying plasmids were found to be conjugative. Phylogenetic analysis revealed the clonal dissemination of K. aerogenes primarily occurred within clinical settings. Notably, some strains in this study showed the potential for clonal transmission, sharing few SNPs between K. aerogenes and KPC- and/or NDM-positive K. aerogenes isolated from various countries. The STs of K. aerogenes strains had significant diversity. WGS analysis showed that the IncFIIK plasmid was the most prevalent carrier of blaKPC-2, and, blaNDM-1/5 were detected on the IncX3 plasmids. The Tn6296 and Tn3000 transposons were most common vehicles for facilitating the transmission of blaKPC-2 and blaNDM-1/5, respectively. This study highlights the importance of continuous screening and surveillance by WGS for analysis of drug-resistant strains in hospital settings, and provide clinical information that supports epidemiological and public health research on human pathogens.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Enterobacter aerogenes , Humanos , beta-Lactamases/genética , Filogeografia , Filogenia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Genômica
6.
Theranostics ; 14(5): 2246-2264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505620

RESUMO

Aim: Adipose tissue (AT) dysfunction that occurs in both obesity and lipodystrophy is associated with the development of cardiomyopathy. However, it is unclear how dysfunctional AT induces cardiomyopathy due to limited animal models available. We have identified vacuolar H+-ATPase subunit Vod1, encoded by Atp6v0d1, as a master regulator of adipogenesis, and adipose-specific deletion of Atp6v0d1 (Atp6v0d1AKO) in mice caused generalized lipodystrophy and spontaneous cardiomyopathy. Using this unique animal model, we explore the mechanism(s) underlying lipodystrophy-related cardiomyopathy. Methods and Results: Atp6v0d1AKO mice developed cardiac hypertrophy at 12 weeks, and progressed to heart failure at 28 weeks. The Atp6v0d1AKO mouse hearts exhibited excessive lipid accumulation and altered lipid and glucose metabolism, which are typical for obesity- and diabetes-related cardiomyopathy. The Atp6v0d1AKO mice developed cardiac insulin resistance evidenced by decreased IRS-1/2 expression in hearts. Meanwhile, the expression of forkhead box O1 (FoxO1), a transcription factor which plays critical roles in regulating cardiac lipid and glucose metabolism, was increased. RNA-seq data and molecular biological assays demonstrated reduced expression of myocardin, a transcription coactivator, in Atp6v0d1AKO mouse hearts. RNA interference (RNAi), luciferase reporter and ChIP-qPCR assays revealed the critical role of myocardin in regulating IRS-1 transcription through the CArG-like element in IRS-1 promoter. Reducing IRS-1 expression with RNAi increased FoxO1 expression, while increasing IRS-1 expression reversed myocardin downregulation-induced FoxO1 upregulation in cardiomyocytes. In vivo, restoring myocardin expression specifically in Atp6v0d1AKO cardiomyocytes increased IRS-1, but decreased FoxO1 expression. As a result, the abnormal expressions of metabolic genes in Atp6v0d1AKO hearts were reversed, and cardiac dysfunctions were ameliorated. Myocardin expression was also reduced in high fat diet-induced diabetic cardiomyopathy and palmitic acid-treated cardiomyocytes. Moreover, increasing systemic insulin resistance with rosiglitazone restored cardiac myocardin expression and improved cardiac functions in Atp6v0d1AKO mice. Conclusion: Atp6v0d1AKO mice are a novel animal model for studying lipodystrophy- or metabolic dysfunction-related cardiomyopathy. Moreover, myocardin serves as a key regulator of cardiac insulin sensitivity and metabolic homeostasis, highlighting myocardin as a potential therapeutic target for treating lipodystrophy- and diabetes-related cardiomyopathy.


Assuntos
Cardiomiopatias Diabéticas , Insuficiência Cardíaca , Resistência à Insulina , Lipodistrofia , Proteínas Nucleares , Transativadores , ATPases Vacuolares Próton-Translocadoras , Animais , Camundongos , Cardiomiopatias Diabéticas/genética , Modelos Animais de Doenças , Glucose/metabolismo , Resistência à Insulina/genética , Lipídeos , Obesidade/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-38409639

RESUMO

Bladder outlet obstruction (BOO) is the primary clinical manifestation of benign prostatic hyperplasia, the most common urinary system disease in elderly men, and leads to associated lower urinary tract symptoms. Although BOO is reportedly associated with increased systemic oxidative stress (OS), the underlying mechanism remains unclear. The elucidation of this mechanism is the primary aim of this study. A Sprague-Dawley rat model of BOO was constructed and used for urodynamic monitoring. The bladder tissue of rats was collected and subjected to real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR), histological examination, and immunohistochemical staining. Through bioinformatics prediction, we found that transforming growth factor ß2 (TGFß2) expression was upregulated in rats with BOO compared with normal bladder tissue. In vitro analyses using primary bladder smooth muscle cells (BSMCs) revealed that hydrogen peroxide (H2O2) induced TGFß2 expression. Moreover, H2O2 induced epithelial-to-mesenchymal transition (EMT) by reducing E-cadherin, an endothelial marker and CK-18, a cytokeratin maker, and increasing mesenchymal markers, including N-cadherin, vimentin, and α-smooth muscle actin (α-SMA) levels. The downregulation of TGFß2 expression in BSMCs using siRNA technology alleviated H2O2-induced changes in EMT marker expression. The findings of the study indicate that TGFß2 plays a crucial role in BOO by participating in OS-induced EMT in BSMCs.

8.
Polymers (Basel) ; 16(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38399937

RESUMO

Experimental investigations and density functional theory (DFT) calculations were carried out to study the comprehensive effect of different 3,5-heptanedioldibenzoate (HDDB) optical isomers as the internal electron donor on the catalytic performance of Ziegler-Natta catalysts. The experimental catalytic activity of HDDB has a positive correlation with the relative content of the mesomer incorporated during catalyst preparation, while the hydrogen response of HDDB displayed a negative correlation with the relative content of the mesomer. In order to apply the DFT calculation results to the macroscopic activity of the catalyst, the content of the active centers of the catalyst was analyzed. Assuming that the content of the active centers is proportional to the internal electron donor content of the catalyst, binary linear regression was carried out, which showed a good linear correlation between experimental activity data and internal electron donor content. Furthermore, the fitted activity of the single active centers aligned well with the calculated activation energies. These results revealed that the catalytic activity of polypropylene (PP) catalysts is dependent on both the active center content and the catalytic activity of an individual active center. Additionally, the lower hydrogen response of HDDB leads to a higher molecular weight of polypropylene obtained from the RS-containing catalyst compared to the SS-containing catalyst. Further study reveals that the hydrogen transfer reactions of 2,4-pentanediol dibenzoate (PDDB)/HDDB are influenced by the orientation of the methyl/ethyl groups in different isomers, which affect the activation energy differences between the hydrogen transfer reaction and the propylene insertion reaction, and finally influence the molecular weight of PP.

9.
Plant Sci ; 343: 112053, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38417718

RESUMO

Retrograde signaling between plastids and the nucleus is vital for chloroplast biogenesis and environmental responses. GENOMES UNCOUPLED1 (GUN1) was proposed to be a central integrator of multiple retrograde signaling pathways in the model plant Arabidopsis thaliana (Arabidopsis). However, the function of GUN1 orthologs in other plant species has not been well studied. Here, we found that many GUN1 orthologs from the Solanaceae family have a short N-terminus before the first pentatricopeptide repeat (PPR) motif which is predicted as intrinsically disordered regions (IDRs). Functional analyses of tomato (Solanum lycopersicum L.) GUN1 (SlGUN1), which does not contain N-terminal IDRs, show that it can complement the GUN phenotype of the Arabidopsis gun1 mutant (Atgun1). However, in contrast to the AtGUN1 protein, which does contain the N-terminal IDRs, the SlGUN1 protein is highly accumulated even after chloroplast biogenesis is completed, suggesting that the N-terminal IDRs may determine the stability of the GUN1 protein. Furthermore, we generated tomato Slgun1 genome-edited mutants via the CRISPR-Cas9 system. The Slgun1 mutants exhibited a typical GUN phenotype under lincomycin (Lin) or norflurazon (NF) treatment. Moreover, Slgun1 mutants are hypersensitive to low concentrations of Lin or NF. Taken together, our results suggest that, although lacking the N-terminal IDRs, SlGUN1 plays conserved roles in plastid retrograde signaling in tomato plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Solanum lycopersicum , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Solanum lycopersicum/genética , Proteínas de Ligação a DNA/genética , Plastídeos/genética , Plastídeos/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Nat Cell Biol ; 26(3): 393-403, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38388853

RESUMO

Cells sense physical forces and convert them into electrical or chemical signals, a process known as mechanotransduction. Whereas extensive studies focus on mechanotransduction at the plasma membrane, little is known about whether and how intracellular organelles sense mechanical force and the physiological functions of organellar mechanosensing. Here we identify the Drosophila TMEM63 (DmTMEM63) ion channel as an intrinsic mechanosensor of the lysosome, a major degradative organelle. Endogenous DmTMEM63 proteins localize to lysosomes, mediate lysosomal mechanosensitivity and modulate lysosomal morphology and function. Tmem63 mutant flies exhibit impaired lysosomal degradation, synaptic loss, progressive motor deficits and early death, with some of these mutant phenotypes recapitulating symptoms of TMEM63-associated human diseases. Importantly, mouse TMEM63A mediates lysosomal mechanosensitivity in Neuro-2a cells, indicative of functional conservation in mammals. Our findings reveal DmTMEM63 channel function in lysosomes and its physiological roles in vivo and provide a molecular basis to explore the mechanosensitive process in subcellular organelles.


Assuntos
Drosophila , Mecanotransdução Celular , Animais , Humanos , Camundongos , Drosophila/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Lisossomos/metabolismo , Mamíferos/metabolismo
11.
Emerg Microbes Infect ; 13(1): 2324068, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38406830

RESUMO

Ceftazidime-avibactam (CZA) resistance is a huge threat in the clinic; however, the underlying mechanism responsible for high-level CZA resistance in Pseudomonas aeruginosa (PA) isolates remains unknown. In this study, a total of 5,763 P. aeruginosa isolates were collected from 2010 to 2022 to investigate the ceftazidime-avibactam (CZA) high-level resistance mechanisms of Pseudomonas aeruginosa (PA) isolates in China. Fifty-six PER-producing isolates were identified, including 50 isolates carrying blaPER-1 in PA, and 6 isolates carrying blaPER-4. Of these, 82.1% (46/56) were classified as DTR-PA isolates, and 76.79% (43/56) were resistant to CZA. Importantly, blaPER-1 and blaPER-4 overexpression led to 16-fold and >1024-fold increases in the MICs of CZA, respectively. WGS revealed that the blaPER-1 gene was located in two different transferable IncP-2-type plasmids and chromosomes, whereas blaPER-4 was found only on chromosomes and was carried by a class 1 integron embedded in a Tn6485-like transposon. Overexpression of efflux pumps may be associated with high-level CZA resistance in blaPER-1-positive strains. Kinetic parameter analysis revealed that PER-4 exhibited a similar kcat/Km with ceftazidime and a high (∼3359-fold) IC50 value with avibactam compared to PER-1. Our study found that overexpression of PER-1 combined with enhanced efflux pump expression and the low affinity of PER-4 for avibactam contributes to high-level resistance to CZA. Additionally, the Tn6485-like transposon plays a significant role in disseminating blaPER. Urgent active surveillance is required to prevent the further spread of high-level CZA resistance in DTR-PA isolates.


Assuntos
Compostos Azabicíclicos , Ceftazidima , Infecções por Pseudomonas , Humanos , Ceftazidima/farmacologia , Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Pseudomonas/epidemiologia , Combinação de Medicamentos , Genômica , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
12.
J Phys Chem B ; 128(9): 2065-2075, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38391132

RESUMO

The blue light using the flavin (BLUF) domain is one of the smallest photoreceptors in nature, which consists of a unique bidirectional electron-coupled proton relay process in its photoactivation reaction cycle. This perspective summarizes our recent efforts in dissecting the photocycle into three elementary processes, including proton-coupled electron transfer (PCET), proton rocking, and proton relay. Using ultrafast spectroscopy, we have determined the temporal sequence, rates, kinetic isotope effects (KIEs), and concertedness of these elementary steps. Our findings provide important implications for illuminating the photoactivation mechanism of the BLUF domain and suggest an engineering platform to characterize intricate reactions involving proton motions that are ubiquitous in nonphotosensitive protein machines.


Assuntos
Luz , Fotorreceptores Microbianos , Prótons , Fotorreceptores Microbianos/química , Transporte de Elétrons , Compostos Orgânicos , Flavinas/química , Proteínas de Bactérias/química
13.
Br J Radiol ; 97(1155): 553-559, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38265293

RESUMO

OBJECTIVES: To evaluate the impact of microwave ablation (MWA) on pain relief, quality of life, mobility, and local tumour progression in adult patients with pelvic osteolytic bone metastasis and to test the safety of MWA. METHODS: This study retrospectively analysed the data from 20 patients with pelvic osteolytic metastases who received MWA combined with percutaneous osteoplasty (POP). The visual analogue scale (VAS), musculoskeletal tumour society system (MSTS), and Quality of Life Questionnaire-Bone Metastases 22 (QLQ-BM22) were used to evaluate the pain, limb function, and quality of life. The intraoperative and postoperative complications were recorded. The tumour recurrence and survival time were analysed during the follow-up period (range 3-26 months). RESULTS: All (n = 20) MWA and POP operations were completed successfully. Four patients (20%; 95% CI, 6%-44%) had mild bone cement leakage from surrounding tissues, and there were no obvious symptoms or serious complications. There were significant differences in VAS, MSTS, and QLQ-BM22 scores before and after the operation (P < .001). During the postoperative follow-up period, 9 patients died. The median survival time was 8 months (range 3-26 months; IQR: 4.5-13; 95% CI, 4.2-15.3 months), and the 1-year survival rate was 65% (13/20; 95% CI, 41%-85%). Tumour recurrence occurred in 4 cases (20%; 95% CI, 6%-44%) after the operation, and the median time of recurrence was 12 months (range 8-16 months; IQR: 8.25-12.75; 95% CI, 5.5-18.5 months). CONCLUSIONS: MWA combined with POP is an effective and safe treatment for pelvic osteolytic metastases. It can significantly relieve local pain, reconstruct limb function, improve patients' quality of life, and effectively control local tumour progression. ADVANCES IN KNOWLEDGE: So far, the experience of using microwave in the treatment of pelvic metastases is still limited. MWA combined with POP in the treatment of pelvic osteolytic metastases can provide significant clinical benefits in acceptable low-risk minimally invasive situations and should be provided to patients with appropriate pelvic metastases in a multidisciplinary approach.


Assuntos
Neoplasias Ósseas , Ablação por Cateter , Cementoplastia , Adulto , Humanos , Cuidados Paliativos , Qualidade de Vida , Recidiva Local de Neoplasia/cirurgia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Dor/etiologia , Neoplasias Ósseas/secundário , Cementoplastia/efeitos adversos , Ablação por Cateter/efeitos adversos
14.
IEEE Trans Med Imaging ; 43(1): 175-189, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37440388

RESUMO

Deep neural networks typically require accurate and a large number of annotations to achieve outstanding performance in medical image segmentation. One-shot and weakly-supervised learning are promising research directions that reduce labeling effort by learning a new class from only one annotated image and using coarse labels instead, respectively. In this work, we present an innovative framework for 3D medical image segmentation with one-shot and weakly-supervised settings. Firstly a propagation-reconstruction network is proposed to propagate scribbles from one annotated volume to unlabeled 3D images based on the assumption that anatomical patterns in different human bodies are similar. Then a multi-level similarity denoising module is designed to refine the scribbles based on embeddings from anatomical- to pixel-level. After expanding the scribbles to pseudo masks, we observe the miss-classified voxels mainly occur at the border region and propose to extract self-support prototypes for the specific refinement. Based on these weakly-supervised segmentation results, we further train a segmentation model for the new class with the noisy label training strategy. Experiments on three CT and one MRI datasets show the proposed method obtains significant improvement over the state-of-the-art methods and performs robustly even under severe class imbalance and low contrast. Code is publicly available at https://github.com/LWHYC/OneShot_WeaklySeg.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Humanos , Aprendizado de Máquina Supervisionado
15.
Int J Antimicrob Agents ; 63(2): 107069, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141833

RESUMO

Carbapenem-resistant Citrobacter freundii (CRCF) poses an enormous challenge in the health care setting. However, the epidemiology and plasmid dynamic evolution of this species have not been well studied, especially for the novel high-risk resistant clones in the intensive care units (ICUs). Here, we characterised the cointegration-based plasmid dynamic evolution of the emerging ST107 CRCF clone in China. Twenty CRCF strains were identified, including ST22 (30%), ST107 (25%), ST396 (10%) and ST116 (10%). Interestingly, the tigecycline (TGC) resistance gene cluster tmexCD2-toprJ2 and blaNDM-1 and blaKPC-2 were simultaneously found in one ST107 strain. Epidemiological analysis showed that ST107 clone contained human- and environment-derived strains from five countries. Notably, 93.75% (15/16) of the isolates harboured blaNDM-1 or blaKPC-2. Plasmid fusion among various ST107 strains of two patients occurred in the same ICU, mediated by Tn5403 and IS26-based insertion and deletion events. pCF1807-2 carried blaNDM-1 while pCF1807-3 carried both tmexCD2-toprJ2 and blaKPC-2 in the CF1807 strain. Importantly, the cointegrate plasmid pCF1807-2 exhibited higher transfer efficiency and could remain stable after serial passage. Notably, no fitness cost was observed for the host. In conclusion, ST107 CRCF is a high-risk resistant clone due to its ability to integrate resistant plasmids. Our findings elucidated the potential threat and global transmission of the ST107 lineage, and reasonable monitoring should be performed to prevent its further spread in hospitals.


Assuntos
Antibacterianos , Citrobacter freundii , Humanos , Citrobacter freundii/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , beta-Lactamases/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , China/epidemiologia
16.
Anal Chem ; 95(51): 18844-18849, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-38086329

RESUMO

Mitochondrial fission is a highly regulated process that can affect metabolism, proliferation, and apoptosis. Division at the periphery enables damaged material to be shed into smaller mitochondria destined for mitophagy, which is found preceded by increased Ca2+ and reactive oxygen species, as well as reduced membrane potential and pH. However, the variation of hypochlorous acid (HOCl) during the peripheral fission has not been well studied, and the existing fluorescent probes are unsuitable for detecting mitochondrial HOCl because of the 0.8-fold decreased pH during this process. Herein, we design a novel CCS (changeable π-conjugation system)-based probe (ON-mito) with a dibenzo[1,4]oxazepine core, which can selectively react with HOCl at pH 6.4, generating an oxazine-containing product that emits at 660 nm. The capability of ON-mito for imaging the HOCl generation in HeLa cells during mitophagy is demonstrated under weakly acidic condition. Further, with ON-mito, we find for the first time a burst increase of the mitochondrial HOCl in COS-7 cells during peripheral fission, which may serve as an important indicator of this process. Probe ON-mito may be useful for studying mitochondrial damage under diverse conditions.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Humanos , Corantes Fluorescentes/metabolismo , Ácido Hipocloroso/metabolismo , Células HeLa , Mitocôndrias/metabolismo , Diagnóstico por Imagem
17.
Molecules ; 28(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38138467

RESUMO

Reactive oxygen species (ROS) are pivotal signaling molecules that control a variety of physiological functions. As a member of the ROS family, peroxynitrite (ONOO-) possesses strong oxidation and nitrification abilities. Abnormally elevated levels of ONOO- can lead to cellular oxidative stress, which may cause several diseases. In this work, based on the rhodamine fluorophore, we designed and synthesized a novel small-molecule fluorescent probe (DH-1) for ONOO-. Upon reaction with ONOO-, DH-1 exhibited a significant fluorescence signal enhancement (approximately 34-fold). Moreover, DH-1 showed an excellent mitochondria-targeting capability. Confocal fluorescence imaging validated its ability to detect ONOO- changes in HeLa and RAW264.7 cells. Notably, we observed the ONOO- generation during the ferroptosis process by taking advantage of the probe. DH-1 displayed good biocompatibility, facile synthesis, and high selectivity, and may have potential applications in the study of ONOO--associated diseases in biosystems.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Humanos , Espécies Reativas de Oxigênio , Mitocôndrias , Rodaminas
18.
Neurotox Res ; 41(6): 627-637, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37971633

RESUMO

Dysfunction in the cholinergic system and oxidative stress are closely related and play roles in Alzheimer's disease (AD). Scopolamine (Scop), which is commonly used to induce cholinergic system damage in cells and animals, also evokes oxidative stress. Our previous study indicated that the peptide (m) RVD-hemopressin (RVD) reversed the memory-impairing effect of Scop in mice by activating cannabinoid receptor 1 (CBR1), but the mechanism was unclear. In this study, we found that RVD inhibited the oxidative stress, apoptosis, decreased cell viability and downregulation of synapse-associated proteins induced by Scop in HT22 cells. The effect was associated with the BDNF/TrkB/Akt pathway, and the effects of RVD outlined above could be blocked by an antagonist of CBR1. These results suggest that RVD may be a potential drug candidate for disorders associated with damage to the cholinergic system and oxidative stress, such as AD.


Assuntos
Doença de Alzheimer , Escopolamina , Camundongos , Animais , Escopolamina/toxicidade , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estresse Oxidativo , Apoptose , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Colinérgicos/farmacologia
19.
Wei Sheng Yan Jiu ; 52(5): 788-792, 2023 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37802903

RESUMO

OBJECTIVE: To understand the public's perceptions and preferences on the designed front-of-package warning labels of prepackaged food, and to evaluate and identify the effective warning label. METHODS: A total of 116 participants were recruited from six provinces(autonomous regions/municipalities) in China. Focus group discussions were conducted with four types of warning labels on prepackaged food. And the score of attitude on different warning labels were compared. RESULTS: There was no difference in the total score of the four warning labels. Total score of black shield label was higher in citizen participants and college education level participants than in their respective counterparts(P<0.05). Parents or primary caregiver of children under 16 years old gave higher scores to each labels than their respective counterparts(P<0.05). The black shield label was most likely to attract the attention of the respondents, most likely to influence the decision on eating and drinking, and most likely to have an unhealthy warning effect. The yellow hexagonal label was least likely to attract the attention of the respondents, least likely to affect the decision to eat and drink food, and least likely to have an unhealthy warning effect. CONCLUSION: Black shield warning label is the most effective.


Assuntos
Rotulagem de Alimentos , Alimentos , Criança , Humanos , Adolescente , Grupos Focais , Preferências Alimentares , China , Comportamento de Escolha
20.
J Glob Antimicrob Resist ; 35: 307-313, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37879457

RESUMO

OBJECTIVES: To characterize a carbapenem-resistant Pseudomonas aeruginosa (CRPA) with an IncP-2 plasmid containing a novel transposon, Tn6485h, which carries both blaIMP-45 and blaAFM-1. METHODS: Antimicrobial susceptibility testing and filter mating experiment were performed on PA942. The stability of the plasmid carrying both blaIMP-45 and blaAFM-1 was carried out. We determined the growth rate of the transconjugant to investigate fitness cost. Additionally, whole-genome sequencing and genomic analysis were performed on PA942. RESULTS: PA942 strain was resistant to most antibiotics except for ciprofloxacin and colistin. Bioinformatics analysis confirmed that PA942 contains an IncP-2 plasmid with a novel transposon Tn6485h carrying both blaIMP-45 and blaAFM-1. The plasmid pPA942-IMP45 can be transferred into recipient bacteria PAO1Rif with an efficiency of 2.2 × 10-7 and the transconjugant PAO1Rif/ pPA942-IMP45 can be stably inherited for 10 generations in the absence of antibiotics. CONCLUSION: We report a carbapenem-resistant P. aeruginosa strain with an IncP-2 plasmid containing a novel transposon, Tn6485h, which carries both blaIMP-45 and blaAFM-1. The IncP-2 plasmid and transposon Tn6485h may contribute to the spread of MBL genes. Therefore, effective measures to prevent the spread of these plasmids should be taken.


Assuntos
Pseudomonas aeruginosa , beta-Lactamases , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia
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