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1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 733-741, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-38926960

RESUMO

OBJECTIVE: To analyze the distribution characteristics of prognostic factors affecting recurrence in peripheral T-cell lymphoma (PTCL) patients with different levels of histone deacetylase (HDAC) based on latent class analysis. METHODS: 112 PTCL patients who were treated in our hospital from September 2012 to September 2019 were selected and divided into recurrence group and non-recurrence group. The clinical data of the two groups of patients were compared. Multivariate logistic regression was used to analyze the risk factors for recurrence. Latent class analysis was used to compare the distribution characteristics of prognostic factors affecting recurrence between the high-risk group and the low-risk group. RESULTS: There were 87 patients (77.68%) in recurrence group and 25 patients (22.32%) in non-recurrence group. The result of multivariate logistic regression showed that ECOG score ≥2, Ann Arbor stage III-IV, IPI score >2, bone marrow involvement, elevated serum ß2-microglobulin (ß2-MG), short-term efficacy not reaching complete remission (CR) or partial remission (PR), and the high expression of HDAC were all independent risk factors for recurrence in patients with PTCL (P <0.05). The recurrence rate of patients with high HDAC levels was significantly higher than that of patiens with low HDAC levels (P <0.05). The results of cluster analysis showed that the risk of recurrence was obviously clustered, and the patients could be divided into high recurrence risk group (HDAC>5 points) and low recurrence risk group (HDAC≤5 points). The results of latent class analysis showed that patients with multiple risk factors account for a higher proportion in the high recurrence risk group, compared with the low recurrence risk group (P <0.05). CONCLUSION: There are differences in recurrence rates among PTCL patients with different HDAC levels and in distribution characteristics of risk factors between high recurrence risk and low recurrence risk groups.


Assuntos
Histona Desacetilases , Linfoma de Células T Periférico , Recidiva Local de Neoplasia , Humanos , Prognóstico , Fatores de Risco , Feminino , Masculino , Pessoa de Meia-Idade
2.
ACS Nano ; 18(24): 15661-15670, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38841753

RESUMO

Methanogenic archaea, characterized by their cell membrane lipid molecules consisting of isoprenoid chains linked to glycerol-1-phosphate via ether bonds, exhibit exceptional adaptability to extreme environments. However, this distinct lipid architecture also complicates the interactions between methanogenic archaea and nanoparticles. This study addresses this challenge by exploring the interaction and transformation of selenium nanoparticles (SeNPs) within archaeal Methanosarcina acetivorans C2A. We demonstrated that the effects of SeNPs are highly concentration-dependent, with chemical stimulation of cellular processes at lower SeNPs concentrations as well as oxidative stress and metabolic disruption at higher concentrations. Notably, we observed the formation of a protein corona on SeNPs, characterized by the selective adsorption of enzymes critical for methylotrophic methanogenesis and those involved in selenium methylation, suggesting potential alterations in protein function and metabolic pathways. Furthermore, the intracellular transformation of SeNPs into both inorganic and organic selenium species highlighted their bioavailability and dynamic transformation within archaea. These findings provide vital insights into the nano-bio interface in archaeal systems, contributing to our understanding of archaeal catalysis and its broader applications.


Assuntos
Methanosarcina , Nanopartículas , Selênio , Selênio/química , Selênio/metabolismo , Methanosarcina/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Estresse Oxidativo
3.
Zhongguo Gu Shang ; 37(5): 500-4, 2024 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-38778535

RESUMO

OBJECTIVE: To explore the value of serum D-dimer (D-D), fibrinogen (FIB), platelet (PLT), C-reactive protein (CRP) and tissue plasminogen activator inhibitor (PAI)-1 levels in predicting lower extremity deep vein thrombosis (DVT) after hip joint surgery in the elderly. METHODS: A retrospective analysis was performed on 165 elderly patients with hip joint surgery admitted from February 2020 to May 2022, including 89 males and 76 females, aged from 60 to 75 years old with an average of (66.43±5.48) years, and there were 102 cases of femoral neck fracture and 63 cases of femoral head necrosis. Serum levels of D-D, FIB, PLT, CRP and PAI-1 tests were performed in all patients within 24 hours after admission, and the patients were divided into DVT group and non-DVT group according to whether they developed DVT. RESULTS: The levels of D-D, FIB, PLT, CRP, and PAI-1 in the DVT group were higher than those in the non-DVT group (P<0.001). Spearman analysis showed that DVT was positively correlated with PLT, CRP, D-D, FIB, and PAI-1 levels (r=0.382, 0.213, 0.410, 0.310, 0.353, all P<0.001). The results of binary Logistic regression analysis showed that D-D and PLT were independent factors affecting the occurrence of DVT (OR=0.038, 0.960, P=0.032, 0.011). The area under curve (AUC) of D-D, FIB, PLT, CRP, PAI-1, and the five combined predictions for DVT were 0.843, 0.692, 0.871, 0.780, 0.819, and 0.960, respectively. The AUC of the five combined predictions was higher than that of the single prediction (P<0.05). CONCLUSION: D-D, FIB, PLT, CRP and PAI-1 are effective in predicting DVT after hip surgery in the elderly, and the combined prediction of the five factors has higher efficacy.


Assuntos
Proteína C-Reativa , Produtos de Degradação da Fibrina e do Fibrinogênio , Extremidade Inferior , Inibidor 1 de Ativador de Plasminogênio , Trombose Venosa , Humanos , Feminino , Masculino , Trombose Venosa/sangue , Trombose Venosa/etiologia , Idoso , Inibidor 1 de Ativador de Plasminogênio/sangue , Proteína C-Reativa/análise , Estudos Retrospectivos , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/cirurgia , Pessoa de Meia-Idade , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Articulação do Quadril/cirurgia , Fibrinogênio/análise , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia
4.
Anal Chem ; 96(22): 8981-8989, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38758609

RESUMO

Addressing the challenge of understanding how cellular interfaces dictate the mechanical resilience and adhesion of archaeal cells, this study demonstrates the role of the surface layer (S-layer) in methanogenic archaea. Using a combination of atomic force microscopy and single-cell force spectroscopy, we quantified the impact of S-layer disruption on cell morphology, mechanical properties, and adhesion capabilities. We demonstrate that the S-layer is crucial for maintaining cell morphology, where its removal induces significant cellular enlargement and deformation. Mechanical stability of the cell surface is substantially compromised upon S-layer disruption, as evidenced by decreased Young's modulus values. Adhesion experiments revealed that the S-layer primarily facilitates hydrophobic interactions, which are significantly reduced after its removal, affecting both cell-cell and cell-bubble interactions. Our findings illuminate the S-layer's fundamental role in methanogen architecture and provide a chemical understanding of archaeal cell surfaces, with implications for enhancing methane production in biotechnological applications.


Assuntos
Microscopia de Força Atômica , Análise de Célula Única , Propriedades de Superfície , Archaea/química , Archaea/metabolismo , Adesão Celular , Interações Hidrofóbicas e Hidrofílicas
5.
ACS Nano ; 18(18): 11828-11836, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38659192

RESUMO

As essential primary producers, cyanobacteria play a major role in global carbon and nitrogen cycles. Though the influence of nanoplastics on the carbon metabolism of cyanobacteria is well-studied, little is known about how nanoplastics affect their nitrogen metabolism, especially under environmentally relevant nitrogen concentrations. Here, we show that nitrogen forms regulated growth inhibition, nitrogen consumption, and the synthesis and release of microcystin (MC) in Microcystis aeruginosa exposed to 10 µg/mL amino-modified polystyrene nanoplastics (PS-NH2) with a particle size of 50 nm under environmentally relevant nitrogen concentrations of nitrate, ammonium, and urea. We demonstrate that PS-NH2 inhibit M. aeruginosa differently in nitrate, urea, and ammonium, with inhibition rates of 51.87, 39.70, and 36.69%, respectively. It is caused through the differences in impairing cell membrane integrity, disrupting redox homeostasis, and varying nitrogen transport pathways under different nitrogen forms. M. aeruginosa respond to exposure of PS-NH2 by utilizing additional nitrogen to boost the production of amino acids, thereby enhancing the synthesis of MC, extracellular polymeric substances, and membrane phospholipids. Our results found that the threat of nanoplastics on primary producers can be regulated by the nitrogen forms in freshwater ecosystems, contributing to a better understanding of nanoplastic risks under environmentally relevant conditions.


Assuntos
Microcystis , Nitrogênio , Microcystis/efeitos dos fármacos , Microcystis/metabolismo , Microcystis/crescimento & desenvolvimento , Nitrogênio/química , Nitrogênio/metabolismo , Microcistinas/metabolismo , Poliestirenos/química , Tamanho da Partícula , Microplásticos/metabolismo , Nanopartículas/química , Nitratos/metabolismo , Nitratos/química , Ureia/metabolismo , Ureia/química , Ureia/farmacologia
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 434-438, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660848

RESUMO

OBJECTIVE: To detect the expression of L-type amino acid transporter 1 (LAT1) in non-Hodgkin's lymphoma (NHL) tissues, and analyze its effect on clinicopathological characteristics and prognosis of patients. METHODS: A total of 92 NHL patients who were treated in our hospital from January 2017 to April 2019 were collected. The expression of LAT1 in NHL tissue was detected by immunohistochemistry and compared between patients with different pathological features (including sex, Ann Arbor stage, extranodal infiltration, Ki-67). The risk factors affecting mortality were analyzed using univariate and multivariate Cox proportional hazards regression. Receiver operating characteristic (ROC) curve was used to detect the predictive value of percentage of LAT1-positive cells in NHL tissue for patient mortality, and analyzing the effect of percentage of LAT1-positive cells on survival rate. RESULTS: LAT1 was positively expressed in NHL tissue. The high expression rate of LAT1 in Ann Arbor stage III and IV groups were higher than that in Ann Arbor stage I group, that in extranodal infiltration group was higher than non-extranodal infiltration group, and that in Ki-67 positive expression group was higher than Ki-67 negative expression group (all P < 0.05). The remission rate after 3 courses of treatment in high-LAT1 expression group was 70.7%, which was lower than 91.2% in low-LAT1 expression group (P < 0.05). Ann Arbor stage III and IV, extranodal invasion, Ki-67 positive expression and increased expression of LAT1 (LAT1-positive cell percentage score ≥2) were risk factors for mortality. The cut-off value of percentage of LAT1-positive cells for predicting NHL death was 45.6%, and the area under the ROC curve was 0.905 (95%CI: 0.897-0.924). The 3-year survival rate of high-LAT1 level group (the percentage of LAT1-positive cells≥45.6%) was 50.00%, which was lower than 78.26% of low-LAT1 level group (P < 0.05). CONCLUSION: The expression level of LAT1 in NHL tissue increases, which affects Ann Arbor stage and extranodal infiltration of patients. LAT1 is a risk factor for death.


Assuntos
Transportador 1 de Aminoácidos Neutros Grandes , Linfoma não Hodgkin , Humanos , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Prognóstico , Masculino , Feminino , Fatores de Risco , Taxa de Sobrevida , Estadiamento de Neoplasias , Curva ROC , Pessoa de Meia-Idade
7.
J Ethnopharmacol ; 327: 117835, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38490290

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The root of Croton crassifolius has been used as a traditional Chinese medicine (TCM), called Radix Croton Crassifolius, and commonly known as "Ji Gu Xiang" in Chinese. Its medicinal value has been recorded in several medical books or handbooks, such as "Sheng Cao Yao Xing Bei Yao", "Ben Cao Qiu Yuan" and "Zhong Hua Ben Cao". It has been traditional employed for treating sore throat, stomach-ache, rheumatism and cancer. AIM OF THE STUDY: At present, there are limited studies on the evaluation of low-polarity extracts of roots in C. crassifolius. Consequently, the aim of this study was to evaluate the antitumor effect of the low-polarity extract of C. crassifolius root. MATERIALS AND METHODS: Extracts were obtained by supercritical fluid extraction. The extracts were tested for antitumor effects in vitro on several cancer cell lines. A CCK-8 kit was used for further analysis of cell viability. A flow cytometer and propidium iodide staining were used to evaluate the cell cycle and apoptosis. Hoechst staining, JC-1 staining and the fluorescence probe DCFH-DA were used to evaluate apoptotic cells. Molecular mechanisms of action were analyzed by quantitative RT‒PCR and Western blotting. Immunohistochemistry was used for the evaluation of xenograft tumors in male BALB/c mice. Finally, molecular docking was employed to predict the bond between the desired bioactive compound and molecular targets. RESULTS: Eleven diterpenoids were isolated from low-polarity C. crassifolius root extracts. Among the compounds, chettaphanin II showed the strongest activity (IC50 = 8.58 µM) against A549 cells. Evaluation of cell viability and the cell cycle showed that Chettaphanin II reduced A549 cell proliferation and induced G2/M-phase arrest. Chttaphanin II significantly induced apoptosis in A549 cells, which was related to the level of apoptosis-related proteins. The growth of tumor tissue was significantly inhibited by chettaphanin II in experiments performed on naked mice. The antitumor mechanism of chettaphanin II is that it can obstruct the mTOR/PI3K/Akt signaling pathway in A549 cells. Molecular docking established that chettaphanin II could bind to the active sites of Bcl-2 and Bax. CONCLUSIONS: Taken together, the natural diterpenoid chettaphanin II was identified as the major antitumor active component, and its potential for developing anticancer therapies was demonstrated for the first time by antiproliferation evaluation in vitro and in vivo.


Assuntos
Cromatografia com Fluido Supercrítico , Croton , Diterpenos , Humanos , Masculino , Camundongos , Animais , Croton/química , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Extratos Vegetais/uso terapêutico , Diterpenos/farmacologia , Proliferação de Células , Camundongos Endogâmicos BALB C , Apoptose , Linhagem Celular Tumoral
8.
Proc Natl Acad Sci U S A ; 121(4): e2317058121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38232281

RESUMO

Integration of methanogenic archaea with photocatalysts presents a sustainable solution for solar-driven methanogenesis. However, maximizing CH4 conversion efficiency remains challenging due to the intrinsic energy conservation and strictly restricted substrates of methanogenic archaea. Here, we report a solar-driven biotic-abiotic hybrid (biohybrid) system by incorporating cadmium sulfide (CdS) nanoparticles with a rationally designed methanogenic archaeon Methanosarcina acetivorans C2A, in which the glucose synergist protein and glucose kinase, an energy-efficient route for glucose transport and phosphorylation from Zymomonas mobilis, were implemented to facilitate nonnative substrate glucose for methanogenesis. We demonstrate that the photo-excited electrons facilitate membrane-bound electron transport chain, thereby augmenting the Na+ and H+ ion gradients across membrane to enhance adenosine triphosphate (ATP) synthesis. Additionally, this biohybrid system promotes the metabolism of pyruvate to acetyl coenzyme A (AcCoA) and inhibits the flow of AcCoA to the tricarboxylic acid (TCA) cycle, resulting in a 1.26-fold augmentation in CH4 production from glucose-derived carbon. Our results provide a unique strategy for enhancing methanogenesis through rational biohybrid design and reprogramming, which gives a promising avenue for sustainably manufacturing value-added chemicals.


Assuntos
Trifosfato de Adenosina , Metano , Metano/metabolismo , Transporte de Elétrons , Trifosfato de Adenosina/metabolismo , Metabolismo Energético , Transporte Biológico , Methanosarcina/metabolismo
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1005929

RESUMO

Objective To investigate the infection of Chlamydia pneumoniae and mycoplasma pneumoniae in adults and their association with atherosclerosis,and to provide theoretical guidance for the prevention of such diseases. Methods A case-control study was used to collect 362 patients who were diagnosed with atherosclerosis from January 2019 to December 2021 in Department of Sichuan Bazhong Central Hospital, and 370 cases who were admitted to the hospital during the same period of physical examination without any cardiovascular disease were selected as the control group, and whole blood samples of the two groups of study subjects were collected, and the infection of Chlamydia pneumoniae and mycoplasma pneumoniae was detected by PCR. Results The infection rate of Chlamydia pneumoniae was 35.49%, the infection rate of mycoplasma was 40.37%, and the co-infection rate was 11.37%;The infection rate of Chlamydia pneumoniae in the control group was 12.04%, the infection rate of mycoplasma was 15.83%, and the coinfection rate was 3.14%, and the difference between the two groups was statistically significant ( χ2=10.926, P=0.023). The effects of mycoplasma, chlamydia, and co-infection on atherosclerotic patients have sex differences, mainly manifested as higher infection rates in men; In addition, the effects of mycoplasma, chlamydia, and co-infection on atherosclerosis patients varied by age, mainly in the 55-70 years age group (P<0.05). Multivariate logistic regression results showed that Chlamydia pneumoniae infection was a risk factor for atherosclerosis (OR=1.303, 95%CI: 1.043-1.677) in the whole population, and chlamydia pneumoniae (OR=1.472, 95% CI: 1.037-1.556), mycoplasma (OR=2.003, 95%CI: 1.637-3.842) and co-infection in men (OR=1.937, 95%CI: 1.380-2.184) were risk factors for atherosclerosis, while co-infection in women (OR=1.699, 95%CI: 1.263-1.765) was a risk factor for atherosclerosis. Conclusion Chlamydia pneumoniae and mycoplasma infection are risk factors for atherosclerosis, and their impact on male groups is greater, and more attention needs to be paid to them.

10.
Work ; 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38160380

RESUMO

BACKGROUND: In a previous study, more attention has been given to the psychological state of doctors than to that of nurses although the workload, working hours, and patient contact time are generally higher for nurses than doctors. The current status of nurses' perceived stress, work engagement, and perceived professional benefit during the routine management of the Corona Virus Disease 2019(COVID-19) pandemic and how their perceived stress affects the other two variables are topics that merit research attention. OBJECTIVE: In this study, the status of nurses' perceived stress, work engagement, and perceived professional benefit during the routine management of the Corona Virus Disease 2019 pandemic was investigated to explore whether their perceived stress level has any effect on the other two variables. METHODS: The convenience sampling method was adopted, and 669 nurses from the First People's Hospital of Jingzhou were selected to participate in this study. Questionnaires on perceived stress, work engagement, and perceived professional benefit were used in the survey, and the data were processed using the SPSS 20.0 program for the descriptive statistics, independent sample t-test, analysis of variance. RESULTS: The total score of the nurses' perceived stress was 18.58±4.37 points. The total scores of their work engagement (43.32±14.01) and perceived professional benefit (140.23±17.75). CONCLUSION: The nurses' total perceived stress score was at an upper-middle level, and their total work engagement and perceived professional benefit scores were relatively high. Overall, perceived stress has a negative effect on nurses' work engagement and perceived professional benefit. That is, the higher the pressure perception of nurses, the lower the degree of work engagement and perceived professional benefit.

11.
Eur Radiol ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889269

RESUMO

OBJECTIVES: To investigate the incremental prognostic value of left ventricular (LV) entropy in a large multi-center population with coronary atherosclerotic heart disease (CAD). BACKGROUND: Current risk stratification of patients with CAD is imprecise and not accurate enough. METHODS: A total of 314 CAD patients who underwent cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) at two medical centers in China between October 2015 and July 2022 were included in this study. Additionally, the 193 patients under 3.0-T field also underwent CMR T1 mapping. LV entropy and extracellular volume (ECV) were calculated from the LGE image of LV myocardium, and major adverse cardiac events (MACEs) were analyzed. RESULTS: Among 314 patients, 110 experienced MACE during a median follow-up of 13 months. The risk of MACE was significantly increased in the high entropy group (log-rank p < 0.001). Entropy maintained an independent association with MACE in a multivariable model including left ventricular ejection fraction (LVEF) and LGE (HR = 1.78; p = 0.001). In addition, the primary endpoint events prognostic value was significantly improved by adding LV entropy to the baseline multivariable model (C-statistic improvement: 0.785-0.818, Delong test: p = 0.001). Similarly, among 193 3.0-T field patients, adding LV entropy to the multivariable baseline model significantly improved the prognostic value of the model for MACE (C-statistic improvement: 0.820-0.898, Delong test: p = 0.004). CONCLUSION: CMR-assessed LV entropy is a powerful independent predictor of MACE in patients with CAD, incremental to common clinical and CMR risk factors, including LVEF, LGE, Native T1, and ECV. CLINICAL RELEVANCE STATEMENT: Left ventricular entropy is a powerful independent predictor of major adverse cardiac events in patients with coronary atherosclerotic heart disease, incremental to common clinical and cardiac magnetic resonance risk factors. KEY POINTS: • Left ventricular entropy, a novel cardiac magnetic resonance parameter of myocardial heterogeneity, demonstrated a robust prognostic association with major adverse cardiac events beyond guideline-based, clinical risk markers. • Entropy can have an important role in the primary prevention of major adverse cardiac events in patients with coronary atherosclerotic heart disease. • Compared with late gadolinium enhancement, extracellular volume, and native T1, entropy could be used to more comprehensively characterize the heterogeneity of left ventricular myocardium.

12.
ACS Nano ; 17(16): 15847-15856, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37530594

RESUMO

Diets comprising selenium-deficient crops have been linked to immune disorders and cardiomyopathy. Selenium nanoparticles (SeNPs) have emerged as a promising nanoplatform for selenium-biofortified agriculture. However, SeNPs fail to reach field-scale applications due to a poor understanding of the fundamental principles of its behavior. Here, we describe the transport, transformation, and bioavailability of SeNPs through a combination of in vivo and in vitro experiments. We show synthesized amorphous SeNPs, when sprayed onto the leaves of Arabidopsis thaliana, are rapidly biotransformed into selenium(IV), nonspecifically incorporated as selenomethionine (SeMet), and specifically incorporated into two selenium-binding proteins (SBPs). The SBPs identified were linked to stress and reactive oxygen species (mainly H2O2 and O2-) reduction, processes that enhance plant growth and primary root elongation. Selenium is transported both upwards and downwards in the plant when SeNPs are sprayed onto the leaves. With the application of Silwet L-77 (a common agrochemical surfactant), selenium distributed throughout the whole plant including the roots, where pristine SeNPs cannot reach. Our results demonstrate that foliar application of SeNPs promotes plant growth without causing nanomaterial accumulation, offering an efficient way to obtain selenium-fortified agriculture.


Assuntos
Nanopartículas , Selênio , Proteínas de Plantas , Peróxido de Hidrogênio , Antioxidantes
13.
Anal Chem ; 95(34): 12785-12793, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37565453

RESUMO

Studies on the adverse effects of nanoplastics (NPs, particle diameter <1000 nm) including physical damage, oxidative stress, impaired cell signaling, altered metabolism, developmental defects, and possible genetic damage have intensified in recent years. However, the analytical detection of NPs is still a bottleneck. To overcome this bottleneck and obtain a reliable and quantitative distribution analysis in complex freshwater ecosystems, an easily applicable NP tracer to simulate their fate and behavior is needed. Here, size- and surface charge-tunable core-shell Au@Nanoplastics (Au@NPs) were synthesized to study the environmental fate of NPs in an artificial freshwater system. The Au core enables the quantitative detection of NPs, while the polystyrene shell exhibits NP properties. The Au@NPs showed excellent resistance to environmental factors (e.g., 1% hydrogen peroxide solution, simulating gastric fluid, acids, and alkalis) and high recovery rates (>80%) from seawater, lake water, sewage, waste sludge, soil, and sediment. Both positively and negatively charged NPs significantly inhibited the growth of duckweed (Lemna minor L.) but had little effect on the growth of cyanobacteria (Microcystis aeruginosa). In addition, the accumulation of positively and negatively charged NPs in cyanobacteria occurred in a concentration-dependent manner, with positively charged NPs more easily taken up by cyanobacteria. In contrast, negatively charged NPs were more readily internalized in duckweed. This study developed a model using a core-shell Au@NP tracer to study the environmental fate and behavior of NPs in various complex environmental systems.


Assuntos
Cianobactérias , Microplásticos , Bioacumulação , Ecossistema , Água Doce , Água do Mar , Poliestirenos
14.
ACS Synth Biol ; 12(7): 2178-2186, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37436915

RESUMO

The Roseobacter clade bacteria are of great significance in marine ecology and biogeochemical cycles, and they are potential microbial chassis for marine synthetic biology due to their versatile metabolic capabilities. Here, we adapted a CRISPR-Cas-based system, base editing, with the combination of nuclease-deactivated Cas9 and deaminase for Roseobacter clade bacteria. Taking the model roseobacter Roseovarius nubinhibens as an example, we achieved precise and efficient genome editing at single-nucleotide resolution without generating double-strand breaks or requesting donor DNAs. Since R. nubinhibens can metabolize aromatic compounds, we interrogated the key genes in the ß-ketoadipate pathway with our base editing system via the introduction of premature STOP codons. The essentiality of these genes was demonstrated, and for the first time, we determined PcaQ as a transcription activator experimentally. This is the first report of CRISPR-Cas-based genome editing in the entire clade of Roseobacter bacteria. We believe that our work provides a paradigm for interrogating marine ecology and biogeochemistry with direct genotype-and-phenotype linkages and potentially opens a new avenue for the synthetic biology of marine Roseobacter bacteria.


Assuntos
Roseobacter , Roseobacter/genética , Roseobacter/metabolismo , Edição de Genes , Fenótipo , Sistemas CRISPR-Cas/genética
15.
Environ Sci Technol ; 57(27): 10079-10088, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37379503

RESUMO

Antibiotic resistance is a global health challenge, and the COVID-19 pandemic has amplified the urgency to understand its airborne transmission. The bursting of bubbles is a fundamental phenomenon in natural and industrial processes, with the potential to encapsulate or adsorb antibiotic-resistant bacteria (ARB). However, there is no evidence to date for bubble-mediated antibiotic resistance dissemination. Here, we show that bubbles can eject abundant bacteria to the air, form stable biofilms over the air-water interface, and provide opportunities for cell-cell contact that facilitates horizontal gene transfer at and over the air-liquid interface. The extracellular matrix (ECM) on bacteria can increase bubble attachment on biofilms, increase bubble lifetime, and, thus, produce abundant small droplets. We show through single-bubble probe atomic force microscopy and molecular dynamics simulations that hydrophobic interactions with polysaccharides control how the bubble interacts with the ECM. These results highlight the importance of bubbles and its physicochemical interaction with ECM in facilitating antibiotic resistance dissemination and fulfill the framework on antibiotic resistance dissemination.


Assuntos
Antagonistas de Receptores de Angiotensina , COVID-19 , Humanos , Pandemias , Inibidores da Enzima Conversora de Angiotensina , Bactérias , Resistência Microbiana a Medicamentos
17.
Proc Natl Acad Sci U S A ; 120(27): e2304306120, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37364127

RESUMO

Understanding the fundamental interaction of nanoparticles at plant interfaces is critical for reaching field-scale applications of nanotechnology-enabled plant agriculture, as the processes between nanoparticles and root interfaces such as root compartments and root exudates remain largely unclear. Here, using iron deficiency-induced plant chlorosis as an indicator phenotype, we evaluated the iron transport capacity of Fe3O4 nanoparticles coated with citrate (CA) or polyacrylic acid (PAA) in the plant rhizosphere. Both nanoparticles can be used as a regulator of plant hormones to promote root elongation, but they regulate iron deficiency in plant in distinctive ways. In acidic root exudates secreted by iron-deficient Arabidopsis thaliana, CA-coated particles released fivefold more soluble iron by binding to acidic exudates mainly through hydrogen bonds and van der Waals forces and thus, prevented iron chlorosis more effectively than PAA-coated particles. We demonstrate through roots of mutants and visualization of pH changes that acidification of root exudates primarily originates from root tips and the synergistic mode of nanoparticle uptake and transformation in different root compartments. The nanoparticles entered the roots mainly through the epidermis but were not affected by lateral roots or root hairs. Our results show that magnetic nanoparticles can be a sustainable source of iron for preventing leaf chlorosis and that nanoparticle surface coating regulates this process in distinctive ways. This information also serves as an urgently needed theoretical basis for guiding the application of nanomaterials in agriculture.


Assuntos
Anemia Hipocrômica , Arabidopsis , Deficiências de Ferro , Nanopartículas de Magnetita , Ferro/metabolismo , Transporte Biológico , Anemia Hipocrômica/metabolismo , Arabidopsis/metabolismo , Raízes de Plantas/metabolismo
18.
Biochem Biophys Res Commun ; 672: 193-200, 2023 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-37356286

RESUMO

Oxidized methylcytidines 5-hydroxymethyl-2'deoxycytidine (5hmdC) and 5-formy-2'deoxycytidine (5fdC) are deaminated by cytidine deaminase (CDA) into genome-toxic variants of uridine, triggering DNA damage and cell death. These compounds are promising chemotherapeutic agents for cancer cells that are resistant to pyrimidine derivative drugs, such as decitabine and cytarabine, which are inactivated by CDA. In our study, we found that cancer cells infected with mycoplasma exhibited a markedly increased sensitivity to 5hmdC and 5fdC, which was independent of CDA expression of cancer cells. In vitro biochemical assay showed that the homologous CDA protein from mycoplasma was capable of deaminating 5hmdC and 5fdC into their uridine form. Moreover, mycoplasma infection increased the sensitivity of cancer cells to 5hmdC and 5fdC, whereas administration of Tetrahydrouridine (THU) attenuated this effect, suggesting that mycoplasma CDA confers a similar effect as human CDA. As mycoplasma infection occurs in many primary tumors, our findings suggest that intratumoral microbes could enhance the tumor-killing effect and expand the utility of oxidized methylcytidines in cancer treatment.


Assuntos
Infecções por Mycoplasma , Neoplasias , Humanos , Uridina , Tetra-Hidrouridina/farmacologia , Citidina Desaminase/genética , Desoxicitidina
19.
Anal Chem ; 95(21): 8325-8331, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37191948

RESUMO

Probing the single-cell mechanobiology in situ is imperative for microbial processes in the medical, industrial, and agricultural realms, but it remains a challenge. Herein, we present a single-cell force microscopy method that can be used to measure microbial adhesion strength under anaerobic conditions in situ. This method integrates atomic force microscopy with an anaerobic liquid cell and inverted fluorescence microscopy. We obtained the nanomechanical measurements of the single anaerobic bacterium Ethanoligenens harbinense YUAN-3 and the methanogenic archaeon Methanosarcina acetivorans C2A and their nanoscale adhesion forces in the presence of sulfoxaflor, a successor of neonicotinoid pesticides. This study presents a new tool for in situ single-cell force measurements of various anoxic and anaerobic species and provides new perspectives for evaluating the potential environmental risk of neonicotinoid applications in ecosystems.


Assuntos
Ecossistema , Anaerobiose , Composição de Bases , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S , Microscopia de Força Atômica/métodos
20.
World J Pediatr ; 19(10): 961-971, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36877432

RESUMO

BACKGROUND: The intrauterine environment has a profound and long-lasting influence on the health of the offspring. However, its impact on the postnatal catch-up growth of twin children remains unclarified. Therefore, this study aimed to explore the maternal factors in pregnancy associated with twin offspring growth. METHODS: This study included 3142 live twin children born to 1571 mothers from the Beijing Birth Cohort Study conducted from 2016 to 2021 in Beijing, China. Original and corrected weight-for-age standard deviation scores of the twin offspring from birth to 36 months of age were calculated according to the World Health Organization Child Growth Standards. The corresponding weight trajectories were identified by the latent trajectory model. Maternal factors in pregnancy associated with the weight trajectories of the twin offspring were examined after adjustment for potential confounders. RESULTS: Five weight trajectories of the twin children were identified, with 4.9% (154/3142) exhibiting insufficient catch-up growth, 30.6% (961/3142), and 46.8% (1469/3142) showing adequate catch-up growth from different birth weights, and 15.0% (472/3142) and 2.7% (86/3142) showing various degrees of excessive catch-up growth. Maternal short stature [adjusted odds ratio (OR) = 0.691, 95% confidence interval (CI) = 0.563-0.848, P = 0.0004] and lower total gestational weight gain (GWG) (adjusted OR = 0.774, 95% CI = 0.616-0.972, P = 0.03) were associated with insufficient catch-up growth of the offspring. Maternal stature (adjusted OR = 1.331, 95% CI = 1.168-1.518, P < 0.001), higher pre-pregnancy body mass index (BMI) (adjusted OR = 1.230, 95% CI = 1.090-1.387, P < 0.001), total GWG (adjusted OR = 1.207, 95% CI = 1.068-1.364, P = 0.002), GWG rate (adjusted OR = 1.165, 95% CI = 1.027-1.321, P = 0.02), total cholesterol (TC) (adjusted OR = 1.150, 95% CI = 1.018-1.300, P = 0.03) and low-density lipoprotein-cholesterol (LDL-C) (adjusted OR = 1.177, 95% CI = 1.041-1.330) in early pregnancy were associated with excessive growth of the offspring. The pattern of weight trajectories was similar between monochorionic and dichorionic twins. Maternal height, pre-pregnancy BMI, GWG, TC and LDL-C in early pregnancy were positively associated with excess growth in dichorionic twins, yet a similar association was observed only between maternal height and postnatal growth in monochorionic twins. CONCLUSION: This study identified the effect of maternal stature, weight status, and blood lipid profiles during pregnancy on postnatal weight trajectories of the twin offspring, thereby providing a basis for twin pregnancy management to improve the long-term health of the offspring.


Assuntos
Trajetória do Peso do Corpo , Gravidez de Gêmeos , Pré-Escolar , Feminino , Humanos , Lactente , Gravidez , Peso ao Nascer , Índice de Massa Corporal , LDL-Colesterol , Estudos de Coortes , Aumento de Peso , Recém-Nascido
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