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1.
Diagnostics (Basel) ; 14(17)2024 Aug 25.
Article in English | MEDLINE | ID: mdl-39272643

ABSTRACT

The accurate and efficient segmentation of the spine is important in the diagnosis and treatment of spine malfunctions and fractures. However, it is still challenging because of large inter-vertebra variations in shape and cross-image localization of the spine. In previous methods, convolutional neural networks (CNNs) have been widely applied as a vision backbone to tackle this task. However, these methods are challenged in utilizing the global contextual information across the whole image for accurate spine segmentation because of the inherent locality of the convolution operation. Compared with CNNs, the Vision Transformer (ViT) has been proposed as another vision backbone with a high capacity to capture global contextual information. However, when the ViT is employed for spine segmentation, it treats all input tokens equally, including vertebrae-related tokens and non-vertebrae-related tokens. Additionally, it lacks the capability to locate regions of interest, thus lowering the accuracy of spine segmentation. To address this limitation, we propose a novel Vertebrae-aware Vision Transformer (VerFormer) for automatic spine segmentation from CT images. Our VerFormer is designed by incorporating a novel Vertebrae-aware Global (VG) block into the ViT backbone. In the VG block, the vertebrae-related global contextual information is extracted by a Vertebrae-aware Global Query (VGQ) module. Then, this information is incorporated into query tokens to highlight vertebrae-related tokens in the multi-head self-attention module. Thus, this VG block can leverage global contextual information to effectively and efficiently locate spines across the whole input, thus improving the segmentation accuracy of VerFormer. Driven by this design, the VerFormer demonstrates a solid capacity to capture more discriminative dependencies and vertebrae-related context in automatic spine segmentation. The experimental results on two spine CT segmentation tasks demonstrate the effectiveness of our VG block and the superiority of our VerFormer in spine segmentation. Compared with other popular CNN- or ViT-based segmentation models, our VerFormer shows superior segmentation accuracy and generalization.

2.
Mol Biol Rep ; 51(1): 991, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39287846

ABSTRACT

Ubiquitination is an essential biological process that is vital for maintaining cellular activity and plays a critical role in precisely regulating protein levels within cells. The SINA (seven in absentia) protein belongs to the RING-type E3 ubiquitin ligase, which is one of the key enzymes involved in the process of ubiquitination. However, there have been few reports on the genome-wide identification of SINA gene family and the functional analysis of its specific genes, particularly in leguminous plants. In this study, a total of 20 MtSINA genes were identified from the genomes of Medicago truncatula, and classified into three subfamilies. These genes are distributed on 7 of 8 chromosomes with chromosome preference. The gene structures of most MtSINA genes are quite similar, and all MtSINA proteins contain conserved RING and SINA functional domains. Moreover, various cis-regulatory elements related to abiotic stress and hormone signals were found in the promoters of MtSINA genes. The expression profile indicates that a majority of MtSINA genes exhibit a significant response to abiotic stress. Furthermore, the study characterized the function of MtSINAL7 in plants and discovered its pivotal role in improving plant stress resistance. In summary, this study provides a new insight into the potential functions of MtSINA genes in Medicago truncatula.


Subject(s)
Gene Expression Regulation, Plant , Medicago truncatula , Multigene Family , Plant Proteins , Stress, Physiological , Medicago truncatula/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant/genetics , Stress, Physiological/genetics , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Phylogeny , Genome, Plant/genetics , Chromosomes, Plant/genetics , Promoter Regions, Genetic/genetics , Ubiquitination/genetics , Gene Expression Profiling/methods , Genes, Plant/genetics
3.
Eur Stroke J ; : 23969873241278193, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39258953

ABSTRACT

BACKGROUND AND PURPOSE: As an angiographic outcome, postoperative collateral formation (PCF) is commonly used to evaluate the effect of STA-MCA bypass in moyamoya disease (MMD), but whether it can reliably reflect clinical outcomes is still unclear. We investigated the association between PCF and clinical outcomes in adult MMD. METHODS: All STA-MCA bypass procedures performed from January 2013 to December 2019 were screened in this prospective cohort study. Patients who acquired presurgical and follow-up catheter angiography were included. The clinical outcomes consisted of symptom improvement and recurrent cerebrovascular events. Logistic and Cox regression and Kaplan-Meier analyses were performed to explore the association between PCF and clinical outcomes. RESULTS: Of 165 included symptomatic hemispheres of 154 patients, 104 (63.0%) and 61 (37.0%) had good and poor PCF, respectively. The hemispheres with good PCF were younger (p = 0.004) and had a higher incidence of hemodynamic dysfunction on admission (p < 0.001) than those with poor PCF. Multivariate logistic regression analysis showed that the good PCF (odd ratio, 28.96; 95% confidence interval (CI), 9.12-91.98; p < 0.001) was associated with a higher incidence of symptom improvement. Multivariate Cox regression analysis showed that the poor PCF (hazard ratio, 3.77; 95% CI, 1.31-10.84; p = 0.014) was associated with a higher incidence of recurrent cerebrovascular events. In the hemorrhagic-onset hemispheres, good PCF group had a higher incidence of symptom improvement (p < 0.001) and a longer hemorrhage-free time (p = 0.031). In the ischemic-onset hemispheres, good PCF group also had a higher incidence of symptom improvement (p < 0.001) and a longer ischemia-free time (p = 0.028). CONCLUSIONS: As a angiographic outcome, collateral formation is a qualified surrogate measure for clinical outcomes after STA-MCA bypass in adult MMD.

4.
Int J Mol Sci ; 25(13)2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39000585

ABSTRACT

Plant flowering time is affected by endogenous and exogenous factors, but its variation patterns among different populations of a species has not been fully established. In this study, 27 Arabidopsis thaliana accessions were used to investigate the relationship between autonomous pathway gene methylation, gene expression and flowering time variation. DNA methylation analysis, RT-qPCR and transgenic verification showed that variation in the flowering time among the Arabidopsis populations ranged from 19 to 55 days and was significantly correlated with methylation of the coding regions of six upstream genes in the autonomous pathway, FLOWERING LOCUS VE (FVE), FLOWERING LOCUS Y (FY), FLOWERING LOCUS D (FLD), PEPPER (PEP), HISTONE DEACETYLASE 5 (HAD5) and Pre-mRNA Processing Protein 39-1 (PRP39-1), as well as their relative expression levels. The expression of FVE and FVE(CS) was modified separately through degenerate codon substitution of cytosine and led to earlier flowering of transgenic plants by 8 days and 25 days, respectively. An accurate determination of methylated sites in FVE and FVE(CS) among those transgenic plants and the recipient Col-0 verified the close relationship between the number of methylation sites, expression and flowering time. Our findings suggest that the methylation variation of these six key upstream transcription factors was associated with the gene expression level of the autonomous pathway and flowering time in Arabidopsis. The FVE(CS) and FVE genes in transgenic plants tended to be hypermethylated, which could be a protective mechanism for plants. However, modification of gene sequences through degenerate codon substitution to reduce cytosine can avoid hypermethylated transferred genes in transgenic plants. It may be possible to partially regulate the flowering of plants by modified trans-epigenetic technology.


Subject(s)
Arabidopsis Proteins , Arabidopsis , DNA Methylation , Flowers , Gene Expression Regulation, Plant , Arabidopsis/genetics , Flowers/genetics , Flowers/growth & development , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Plants, Genetically Modified/genetics , Epigenesis, Genetic
5.
Sci One Health ; 3: 100064, 2024.
Article in English | MEDLINE | ID: mdl-39077388

ABSTRACT

Background: In the 21st century, as globalization accelerates and global public health crises occur, the One Health approach, guided by the holistic thinking of human-animal-environment and emphasizing interdisciplinary collaboration to address global health issues, has been strongly advocated by the international community. An immediate requirement exists for the creation of an assessment tool to foster One Health initiatives on both global and national scales. Methods: Built upon extensive expert consultations and dialogues, this follow-up study enhances the 2022 global One Health index (GOHI) indicator system. The GOHI framework is enriched by covering three indices, e.g. external drivers index (EDI), intrinsic drivers index (IDI), and core drivers index (CDI). The comprehensive indicator system incorporates 13 key indicators, 50 indicators, and 170 sub I-indicators, utilizing a fuzzy analytic hierarchy process to ascertain the weight for each indicator. Weighted and summed, the EDI, IDI, and CDI scores contribute to the computation of the overall GOHI 2022 score. By comparing the ranking and the overall scores among the seven regions and across 160 countries/territories, we have not only derived an overall profile of the GOHI 2022 scores, but also assessed the GOHI framework. We also compared rankings of indicators and sub I-indicators to provide greater clarity on the strengths and weaknesses of each region within the One Health domains. Results: The GOHI 2022 performance reveals significant disparities between countries/territories ranged from 39.03 to 70.61. The global average score of the GOHI 2022 is 54.82. The average score for EDI, IDI, and CDI are 46.57, 58.01, and 57.25, respectively. In terms of global rankings, countries from North America, Europe and Central Asia, East Asia and Pacific present higher scores. In terms of One Health domains of CDI, the lowest scores are observed in antimicrobial resistance (median: 43.09), followed by food security (median: 53.78), governance (median: 54.77), climate change (median: 64.12) and zoonotic diseases (median: 69.23). Globally, the scores of GOHI vary spatially, with the highest score in North America while lowest in sub-Saharan Africa. In addition, evidence shows associations between the socio-demographic profile of countries/territories and their GOHI performance in certain One Health scenarios. Conclusion: The objective of GOHI is to guide impactful strategies for enhancing capacity building in One Health. With advanced technology and an annually updated database, intensifying efforts to refine GOHI's data-mining methodologies become imperative. The goal is to offer profound insights into disparities and progressions in practical One Health implementation, particularly in anticipation of future pandemics.

6.
iScience ; 27(4): 109297, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38715943

ABSTRACT

The One Health (OH) approach is used to control/prevent zoonotic events. However, there is a lack of tools for systematically assessing OH practices. Here, we applied the Global OH Index (GOHI) to evaluate the global OH performance for zoonoses (GOHI-Zoonoses). The fuzzy analytic hierarchy process algorithm and fuzzy comparison matrix were used to calculate the weights and scores of five key indicators, 16 subindicators, and 31 datasets for 160 countries and territories worldwide. The distribution of GOHI-Zoonoses scores varies significantly across countries and regions, reflecting the strengths and weaknesses in controlling or responding to zoonotic threats. Correlation analyses revealed that the GOHI-Zoonoses score was associated with economic, sociodemographic, environmental, climatic, and zoological factors. Additionally, the Human Development Index had a positive effect on the score. This study provides an evidence-based reference and guidance for global, regional, and country-level efforts to optimize the health of people, animals, and the environment.

7.
Infect Dis Model ; 9(2): 618-633, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38645696

ABSTRACT

The rapid acceleration of global warming has led to an increased burden of high temperature-related diseases (HTDs), highlighting the need for advanced evidence-based management strategies. We have developed a conceptual framework aimed at alleviating the global burden of HTDs, grounded in the One Health concept. This framework refines the impact pathway and establishes systematic data-driven models to inform the adoption of evidence-based decision-making, tailored to distinct contexts. We collected extensive national-level data from authoritative public databases for the years 2010-2019. The burdens of five categories of disease causes - cardiovascular diseases, infectious respiratory diseases, injuries, metabolic diseases, and non-infectious respiratory diseases - were designated as intermediate outcome variables. The cumulative burden of these five categories, referred to as the total HTD burden, was the final outcome variable. We evaluated the predictive performance of eight models and subsequently introduced twelve intervention measures, allowing us to explore optimal decision-making strategies and assess their corresponding contributions. Our model selection results demonstrated the superior performance of the Graph Neural Network (GNN) model across various metrics. Utilizing simulations driven by the GNN model, we identified a set of optimal intervention strategies for reducing disease burden, specifically tailored to the seven major regions: East Asia and Pacific, Europe and Central Asia, Latin America and the Caribbean, Middle East and North Africa, North America, South Asia, and Sub-Saharan Africa. Sectoral mitigation and adaptation measures, acting upon our categories of Infrastructure & Community, Ecosystem Resilience, and Health System Capacity, exhibited particularly strong performance for various regions and diseases. Seven out of twelve interventions were included in the optimal intervention package for each region, including raising low-carbon energy use, increasing energy intensity, improving livestock feed, expanding basic health care delivery coverage, enhancing health financing, addressing air pollution, and improving road infrastructure. The outcome of this study is a global decision-making tool, offering a systematic methodology for policymakers to develop targeted intervention strategies to address the increasingly severe challenge of HTDs in the context of global warming.

8.
Ultrason Sonochem ; 103: 106801, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38364485

ABSTRACT

Particle engulfment plays a vital role in the application of particulate reinforced metal matrix composites fabricated by ingot metallurgy. During solidification, particles are nevertheless pushed by an advancing front. As a model system, TiB2p/Al composites were used to investigate the particle engulfment facilitated by acoustic cavitation. The implosion of bubbles drives the particles plunging towards the solid/liquid interface, which increases the engulfment probability. The secondary dendrite arms are refined from 271.2 µm to 98.0 µm as a result of the forced movements of TiB2 particles. Owing to the particle engulfment and dendrite refinement, the composite with ultrasound vibration treatment shows a more rapid work-hardening rate and higher strength.

9.
Front Psychol ; 14: 1260561, 2023.
Article in English | MEDLINE | ID: mdl-38098517

ABSTRACT

Introduction: Numerous smokers are cognizant of the detrimental effects associated with this habit yet exhibit a persistent reluctance to cease their tobacco consumption. Self-exempt beliefs serve as an obstacle to the cessation of this addictive behavior. This research explored the impact of self-exempt beliefs on the readiness to quit smoking based on the Protection Motivation Theory (PMT) model and the mediating roles of threat appraisal and coping appraisal. Methods: Self-exempt beliefs, PMT constructs, and the intention to quit smoking constituted the theoretical model. The questionnaires were collected from 488 Chinese adult male smokers based on snowball sampling. Exploratory Factor Analysis (EFA) was used to examine the underlying factor structure of the pre-designed self-exempt beliefs scale. The reliability, validity, path coefficients, and explanatory power of the model were calculated using Partial Least Squares Structural Equation Modeling (PLS-SEM). Results and discussion: The results showed that : (1) three common factors (skeptic beliefs, bulletproof beliefs, and "worth it" beliefs) with a total of 11 items were retained after EFA; (2) skeptic beliefs and "worth it" beliefs had a significantly negative effect on both threat appraisal and coping appraisal, while bulletproof beliefs did not; (3) bulletproof beliefs had a significantly positive direct impact on intention to quit, "worth it" beliefs had a significantly negative direct impact on intention, while skeptic beliefs had no significantly direct impact on intention; (4) threat appraisal and coping appraisal positively and significantly predicted cessation intention; and (5) threat appraisal and coping appraisal, as two main cognitive processes, acted as full mediations between skeptic beliefs and the intention to quit, as complementary partial mediations between "worth it" beliefs and the intention, and as non-mediation between bulletproof beliefs and the intention. Our findings suggest that efforts to undermine or "prevent" these self-exempt beliefs, particularly "worth it" and skeptic beliefs, may be an effective tactic for health communication interventions for quitting smoking.

10.
One Health ; 17: 100607, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37588422

ABSTRACT

Background: Due to emerging issues such as global climate change and zoonotic disease pandemics, the One Health approach has gained more attention since the turn of the 21st century. Although One Health thinking has deep roots and early applications in Chinese history, significant gaps exist in China's real-world implementation at the complex interface of the human-animal-environment. Methods: We abstracted the data from the global One Health index study and analysed China's performance in selected fields based on Structure-Process-Outcome model. By comparing China to the Belt & Road and G20 countries, the advances and gaps in China's One Health performance were determined and analysed. Findings: For the selected scientific fields, China generally performs better in ensuring food security and controlling antimicrobial resistance and worse in addressing climate change. Based on the SPO model, the "structure" indicators have the highest proportion (80.00%) of high ranking and the "outcome" indicators have the highest proportion (20.00%) of low ranking. When compared with Belt and Road countries, China scores above the median in almost all indicators (16 out of 18) under the selected scientific fields. When compared with G20 countries, China ranks highest in food security (scores 72.56 and ranks 6th), and lowest in climate change (48.74, 11th). Conclusion: Our results indicate that while China has made significant efforts to enhance the application of the One Health approach in national policies, it still faces challenges in translating policies into practical measures. It is recommended that a holistic One Health action framework be established for China in accordance with diverse social and cultural contexts, with a particular emphasis on overcoming data barriers and mobilizing stakeholders both domestically and globally. Implementation mechanisms, with clarified stakeholder responsibilities and incentives, should be improved along with top-level design.

11.
Infect Dis Poverty ; 12(1): 70, 2023 Aug 03.
Article in English | MEDLINE | ID: mdl-37537637

ABSTRACT

BACKGROUND: One Health approach is crucial to tackling complex global public health threats at the interface of humans, animals, and the environment. As outlined in the One Health Joint Plan of Action, the international One Health community includes stakeholders from different sectors. Supported by the Bill & Melinda Gates Foundation, an academic community for One Health action has been proposed with the aim of promoting the understanding and real-world implementation of One Health approach and contribution towards the Sustainable Development Goals for a healthy planet. MAIN TEXT: The proposed academic community would contribute to generating high-quality scientific evidence, distilling local experiences as well as fostering an interconnected One Health culture and mindset, among various stakeholders on different levels and in all sectors. The major scope of the community covers One Health governance, zoonotic diseases, food security, antimicrobial resistance, and climate change along with the research agenda to be developed. The academic community will be supported by two committees, including a strategic consultancy committee and a scientific steering committee, composed of influential scientists selected from the One Health information database. A workplan containing activities under six objectives is proposed to provide research support, strengthen local capacity, and enhance global participation. CONCLUSIONS: The proposed academic community for One Health action is a crucial step towards enhancing communication, coordination, collaboration, and capacity building for the implementation of One Health. By bringing eminent global experts together, the academic community possesses the potential to generate scientific evidence and provide advice to local governments and international organizations, enabling the pursuit of common goals, collaborative policies, and solutions to misaligned interests.


Subject(s)
Global Health , One Health , Animals , Humans , Zoonoses/prevention & control , Public Health , Capacity Building
12.
J Chromatogr Sci ; 61(9): 885-891, 2023 Nov 05.
Article in English | MEDLINE | ID: mdl-37009711

ABSTRACT

In view of the adsorption performance of polyvinylpolypyrrolidone (PVPP) to flavones, the adsorption and purification of bamboo leaf flavones (BLFs) by PVPP were studied. The flavones solution was adsorbed by PVPP column chromatography, and then establish a relatively effective method for elution and purification of flavones from bamboo leaf. The optimal separation conditions of column chromatography were determined as the following: the feed concentration of 10 mg/mL, the ratio of diameter to height of 1:1.9, eluents of deionized water (21 mL) and 70% ethanol (800 mL) with a flow rate of 0.33 mL/min. The purity of flavones obtained from ethanol eluents (80-480 mL) was 96.2%. This showed that the PVPP had an ideal adsorption and purification effect on BLFs.


Subject(s)
Flavones , Flavones/analysis , Adsorption , Plant Leaves/chemistry , Ethanol/chemistry
13.
Article in English | MEDLINE | ID: mdl-36767848

ABSTRACT

For a long time, studies on the peer effect of physical activity among adolescents have focused on relevance rather than causality. This article provides empirical evidence of the peer effect of physical activity among adolescents using data from the China Education Panel Survey. The results show that the peer effect increases physical activity by about 6.757-8.984 min per week among classmates, a finding consistent with previous studies. Using the instrumental variable approach and considering the potential missing variables, the peer effect increases physical activity by 23.923-27.410 min per week, representing a threefold increase. In addition, the general attitude towards sports in class plays a significantly influential role, accounting for 20% of the peer effect of physical activity.


Subject(s)
Schools , Sports , Humans , Adolescent , Exercise , Peer Group , Attitude , China
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 122011, 2023 Feb 05.
Article in English | MEDLINE | ID: mdl-36279799

ABSTRACT

A fluorescent probe MAM based on triphenylamine scaffold was synthesized. The electron donating group 4-methoxyphenyl and the electron acceptor dicyanoethylene were introduced on the triphenylamine scaffold to form a D-π-A fluorescent probe. The probe MAM exhibited the typical aggregation-induced emission (AIE) and intramolecular charge transfer (ICT) characteristics with the bright orange-red fluorescent emission in high water fraction (fw ≥ 50%) and negligible emission in low water fraction. The probe MAM could detect hydrazine (N2H4) in DMSO-tris-HCl (10 mM, pH7.4, v/v, 3:1) with high selectivity and sensitivity. The specific reaction between MAM and hydrazine and the formation of the hydrazone blocked the ICT process, and the system emitted the cyan fluorescence which could be easily observed by naked eyes. The limit of detection (LOD) was 0.196 µM (6.25 ppb), which is lower than the US Environmental Protection Agency standard (10 ppb). The test strips prepared by the probe MAM could realize the convenient and rapid detection of N2H4 solution and vapor. The application of MAM in actual water samples and cells was investigated, and the results showed that MAM could sense N2H4 in environmental and biological aspects with potential application prospects.


Subject(s)
Fluorescent Dyes , Hydrazines , Fluorescent Dyes/pharmacology , Spectrometry, Fluorescence/methods , Water , Amines
15.
Plant Mol Biol ; 111(3): 233-248, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36508138

ABSTRACT

KEY MESSAGE: Here we provided a high temporal-resolution transcriptome atlas of maize embryo sac and ovule to reveal the gene activity dynamic during early seed development. The early maize (Zea mays) seed development is initiated from double fertilization in the embryo sac and needs to undergo a highly dynamic and complex development process to form the differentiated embryo and endosperm. Despite the importance of maize seed for food, feed, and biofuel, many regulators responsible for controlling its early development are not known yet. Here, we reported a high temporal-resolution transcriptome atlas of embryo sac and ovule based on 44 time point samples collected within the first four days of seed development. A total of 25,187 genes including 1598 transcription factors (TFs) involved in early seed development were detected. Global comparisons of the expressions of these genes revealed five distinct development stages of early seed, which are mainly related to double fertilization, asymmetric cell division of the zygote, as well as coenocyte formation, cellularization and differentiation in endosperm. We identified 3327 seed-specific genes, which more than one thousand seed-specific genes with main expressions during early seed development were newly identified here, including 859 and 186 genes predominantly expressed in the embryo sac and ovule, respectively. Combined with the published transcriptome data of seed, we uncovered the dominant auxin biosynthesis, transport and signaling related genes at different development stages and subregions of seed. These results are helpful for understanding the genetic control of early seed development.


Subject(s)
Transcriptome , Zea mays , Zea mays/genetics , Ovule , Seeds/genetics , Endosperm/metabolism , Gene Expression Regulation, Plant
16.
Curr Microbiol ; 79(10): 293, 2022 Aug 16.
Article in English | MEDLINE | ID: mdl-35972650

ABSTRACT

Ursolic acid (UA) exists in a variety of medicinal plants. UA exhibits antimicrobial activity against several microorganisms; however, little is known regarding the potential antifungal effect of UA on Cryptococcus neoformans (C. neoformans). The antifungal and antibiofilm activities of UA on C. neoformans H99 were evaluated in this study. Minimum inhibitory concentration (MIC) of UA against C. neoformans H99 was determined by microdilution technique, and its action mode was elucidated by clarifying the variations in cell membrane integrity, capsule, and melanin production. Moreover, the inhibition and dispersal effects of UA on biofilm formation and mature biofilms by C. neoformans H99 were evaluated using crystal violet (CV) assay, optical microscopy, field emission scanning electron microscopy and confocal laser scanning microscopy. The results indicated that the MIC value of UA against C. neoformans H99 was 0.25 mg/mL. UA disrupted the cell membrane integrity, inhibited the capsule and melanin production of C. neoformans H99 in a concentration-dependent manner. Further, UA presented the inhibitory effect on biofilm formation and dispersed mature biofilms, as well as compromised the cell membrane integrity of C. neoformans H99 cells within biofilms. Together, these results indicate that UA might be a potential therapeutic option for the treatment of C. neoformans-related infections.


Subject(s)
Cryptococcosis , Cryptococcus neoformans , Antifungal Agents/metabolism , Antifungal Agents/pharmacology , Biofilms , Cryptococcosis/drug therapy , Cryptococcus neoformans/metabolism , Melanins/metabolism , Melanins/pharmacology , Microbial Sensitivity Tests , Triterpenes , Ursolic Acid
17.
Biofouling ; 38(6): 558-574, 2022 07.
Article in English | MEDLINE | ID: mdl-35818738

ABSTRACT

Cryptococcus neoformans is an important opportunistic fungal pathogen that causes various infections. Here, the antifungal and antibiofilm activities of plumbagin against C. neoformans and the underlying mechanisms were evaluated. The minimum inhibitory concentration (MIC) of plumbagin against C. neoformans H99 was 8 µg ml-1. Plumbagin disrupted the cell membrane integrity and reduced the metabolic activities of C. neoformans H99. C. neoformans H99 biofilm cells were damaged by plumbagin at a concentration of 64 µg ml-1, whereas 48-h mature biofilms were dispersed at a plumbagin concentration of 128 µg ml-1. Whole-transcriptome analysis of plumbagin-treated C. neoformans H99 in the biofilm and planktonic states identified differentially expressed genes enriched in several important cellular processes (cell membrane, ribosome biogenesis, fatty acid synthesis, melanin and capsule production). Notably, plumbagin damaged biofilm cells by downregulating FAS1 and FAS2 expression. Thus, plumbagin can be exploited as an antifungal agent to combat C. neoformans-related infections.


Subject(s)
Cryptococcosis , Cryptococcus neoformans , Antifungal Agents/metabolism , Antifungal Agents/pharmacology , Biofilms , Cryptococcosis/microbiology , Cryptococcus neoformans/genetics , Cryptococcus neoformans/metabolism , Microbial Sensitivity Tests , Naphthoquinones
18.
Front Cell Infect Microbiol ; 12: 884793, 2022.
Article in English | MEDLINE | ID: mdl-35669114

ABSTRACT

Fungal populations are commonly found in natural environments and present enormous health care challenges, due to increased resistance to antifungal agents. Paeonol exhibits antifungal activities; nevertheless, the antifungal and antibiofilm activities of paeonol against Candida albicans and Cryptococcus neoformans remain largely unexplored. Here, we aimed to evaluate the antifungal and antibiofilm activities of paeonol against C. albicans and/or C. neoformans (i.e., against mono- or dual-species). The minimum inhibitory concentrations (MICs) of paeonol for mono-species comprising C. albicans or C. neoformans were 250 µg ml-1, whereas the MIC values of paeonol for dual-species were 500 µg ml-1. Paeonol disrupted cell membrane integrity and increased the influx of gatifloxacin into cells of mono- and dual-species cells, indicating an antifungal mode of action. Moreover, paeonol at 8 times the MIC damaged mono- and dual-species cells within C. albicans and C. neoformans biofilms, as it did planktonic cells. In particular, at 4 and 8 mg ml-1, paeonol efficiently dispersed preformed 48-h biofilms formed by mono- and dual-species cells, respectively. Paeonol inhibited effectively the yeast-to-hyphal-form transition of C. albicans and impaired capsule and melanin production of C. neoformans. The addition of 10 MIC paeonol to the medium did not shorten the lifespan of C. elegans, and 2 MIC paeonol could effectively protect the growth of C. albicans and C. neoformans-infected C. elegans. Furthermore, RNA sequencing was employed to examine the transcript profiling of C. albicans and C. neoformans biofilm cells in response to 1/2 MIC paeonol. RNA sequencing data revealed that paeonol treatment impaired biofilm formation of C. albicans by presumably downregulating the expression level of initial filamentation, adhesion, and growth-related genes, as well as biofilm biosynthesis genes, whereas paeonol inhibited biofilm formation of C. neoformans by presumably upregulating the expression level of ergosterol biosynthesis-related genes. Together, the findings of this study indicate that paeonol can be explored as a candidate antifungal agent for combating serious single and mixed infections caused by C. albicans and C. neoformans.


Subject(s)
Cryptococcosis , Cryptococcus neoformans , Acetophenones , Animals , Antifungal Agents/pharmacology , Biofilms , Caenorhabditis elegans , Candida albicans , Microbial Sensitivity Tests
19.
Infect Drug Resist ; 15: 2865-2878, 2022.
Article in English | MEDLINE | ID: mdl-35686192

ABSTRACT

Purpose: Several Escherichia coli pathotypes still constitute an important public health concern owing to its pathogenicity and antimicrobial resistance. Moreover, biofilm formation of E. coli can allow the strains to interfere with host and antimicrobial eradication, thus conferring additional resistance. The association between the formation of biofilm and antimicrobial resistance determinants has been extensively exploited; nevertheless, there is still no definite conclusion. The purpose of this study was to provide additional data to augment the present knowledge about the subject. Methods: Antibiotic resistance/susceptibility profiles of 81 isolates from pediatric individuals in China between 2011 and 2014 against 20 antibiotics were assessed using the VITEK 2 system. Biofilm-forming capacities were evaluated using the crystal violet staining method, confocal laser scanning microscopy (CLSM), and field emission scanning electron microscopy. Biofilm compositions inside the biofilm formed by representative strains were assessed using CLSM. The effects of antibiotics on biofilms generated by E. coli strains of different biofilm-forming ability were examined using CLSM in combination with gatifloxacin. The relationships between antibiotic resistance, biofilm formation, and biofilm-specific resistance in E. coli isolates were investigated. Results: The results showed that 23 isolates were classified as multidrug-resistant, and 57 isolates were classified as extensively drug-resistant (XDR). Among the 69 isolates with the ability to form biofilms, 46 isolates were stronger biofilm formers. Correlation analysis demonstrated that strain populations exhibiting more robust biofilm formation likely contained larger proportions of XDR isolates. Conclusion: Together, our study implies that there was an association between biofilm-formation and resistance to several antibiotics for XDR-E. coli isolates, and would provide novel insights regarding the prevention and treatment against E. coli-related infections.

20.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-935051

ABSTRACT

@#[摘 要] 目的:探讨胶质母细胞瘤(GBM)患者肿瘤组织来源的GBM类器官(GBO)模型的制备方法。方法:选取2021年广东三九脑科医院新诊断经病理确诊的8例GBM患者的新鲜肿瘤组织标本,将其剪成0.5~1 mm大小的组织碎片并用特制的培养基进行培养,待其成球且直径达到1 mm时剪小传代,同时选取培养2周以上的GBO进行石蜡包埋、切片,后进行H-E染色和免疫组化染色检测,并与亲本GBM组织进行组织学与细胞学的比较。结果:成功培养2例可传代冻存的GBO,并建立GBO生物库。H-E染色结果显示,GBO保留了与亲本GBM组织相似的组织结构和细胞形态;免疫组化实验结果显示,GBO与GBM组织中GFAP、OLIG2、Ki67和ATRX分子的表达情况一致。结论:将患者来源的GBM组织在体外剪小并用特制培养基培养,可构建与GBM患者肿瘤组织在组织和细胞层面一致的GBO。

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