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1.
Ecotoxicol Environ Saf ; 278: 116432, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38728947

RESUMO

Cadmium (Cd) pollution is a serious global environmental problem, which requires a global concern and practical solutions. Microbial remediation has received widespread attention owing to advantages, such as environmental friendliness and soil amelioration. However, Cd toxicity also severely deteriorates the remediation performance of functional microorganisms. Analyzing the mechanism of bacterial resistance to Cd stress will be beneficial for the application of Cd remediation. In this study, the bacteria strain, up to 1400 mg/L Cd resistance, was employed and identified as Proteus mirabilis Ch8 (Ch8) through whole genome sequence analyses. The results indicated that the multiple pathways of immobilizing and detoxifying Cd maintained the growth of Ch8 under Cd stress, which also possessed high Cd extracellular adsorption. Firstly, the changes in surface morphology and functional groups of Ch8 cells were observed under different Cd conditions through SEM-EDS and FTIR analyses. Under 100 mg/L Cd, Ch8 cells exhibited aggregation and less flagella; the Cd biosorption of Ch8 was predominately by secreting exopolysaccharides (EPS) and no significant change of functional groups. Under 500 mg/L Cd, Ch8 were present irregular polymers on the cell surface, some cells with wrapping around; the Cd biosorption capacity exhibited outstanding effects (38.80 mg/g), which was mainly immobilizing Cd by secreting and interacting with EPS. Then, Ch8 also significantly enhanced the antioxidant enzyme activity and the antioxidant substance content under different Cd conditions. The activities of SOD and CAT, GSH content of Ch8 under 500 mg/L Cd were significantly increased by 245.47%, 179.52%, and 241.81%, compared to normal condition. Additionally, Ch8 significantly induced the expression of Acr A and Tol C (the resistance-nodulation-division (RND) efflux pump), and some antioxidant genes (SodB, SodC, and Tpx) to reduce Cd damage. In particular, the markedly higher expression levels of SodB under Cd stress. The mechanism of Ch8 lays a foundation for its application in solving soil remediation.

2.
J Colloid Interface Sci ; 670: 348-356, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38763030

RESUMO

The depressed directional separation of photogenerated carriers and weak CO2 adsorption/activation activity are the main factors hampering the development of artificial photosynthesis. Herein, Na ions are embedded in graphitic carbon nitride (g-C3N4) to achieve directional migration of the photogenerated electrons to Na sites, while the electron-rich Na sites enhance CO2 adsorption and activation. Na/g-C3N4 (NaCN) shows improved photocatalytic reduction activity of CO2 to CO and CH4, and under simulated sunlight irradiation, the CO yield of NaCN synthesized by embedding Na at 550°C (NaCN-550) is 371.2 µmol g-1 h-1, which is 58.9 times more than that of the monomer g-C3N4. By means of theoretical calculations and experiments including in situ fourier transform infrared spectroscopy, the mechanism is investigated. This strategy which improves carrier separation and reduces the energy barrier at the same time is important to the development of artificial photosynthesis.

3.
Bioorg Med Chem Lett ; : 129793, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735343

RESUMO

Neuromuscular blocking agents (NMBAs) are widely used in anesthesia for intubation and surgical muscle relaxation. Novel atracurium and mivacurium derivatives were developed, with compounds 18c, 18d, and 29a showing mivacurium-like relaxation at 27.27 nmol/kg, and 15b, 15c, 15e, and 15h having a shorter duration at 272.7 nmol/kg. The structure-activity and configuration-activity relationships of these derivatives and 29a's binding to nicotinic acetylcholine receptors were analyzed through molecular docking. Rabbit trials showed 29a has a shorter duration compared to mivacurium. This suggests that linker properties, ammonium group substituents, and configuration are crucial for NMBA activity and duration, with compound 29a emerging as a potential ultra-short-acting NMBA.

4.
Sci Rep ; 14(1): 10729, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730055

RESUMO

Due to the BCS theory, hydrogen, the lightest element, would be the prospect of room-temperature superconductor after metallization, but because of the difficulty of the hydrogen metallization, the theory about hydrogen pre-compression was proposed that the hydrogen-rich compounds could be a great option for the high Tc superconductors. The superior properties of TmH6, YbH6 and LuH6 indicated the magnificent potential of heavy rare earth elements for low-pressure stability. Here, we designed XTmH12 (X = Y, Yb, Lu, and La) to obtain higher Tc while maintaining low pressure stability. Most prominently, YbTmH12 can stabilize at a pressure of 60 GPa. Compared with binary TmH6 hydride, its Tc was increased to 48 K. The results provide an effective method for the rational design of moderate pressure stabilized hydride superconductors.

5.
J Agric Food Chem ; 72(20): 11321-11330, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38714361

RESUMO

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a crucial target enzyme in albino herbicides. The inhibition of HPPD activity interferes with the synthesis of carotenoids, blocking photosynthesis and resulting in bleaching and necrosis. To develop herbicides with excellent activity, a series of 3-hydroxy-2-(6-substituted phenoxynicotinoyl)-2-cyclohexen-1-one derivatives were designed via active substructure combination. The title compounds were characterized via infrared spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopies, and high-resolution mass spectrometry. The structure of compound III-17 was confirmed via single-crystal X-ray diffraction. Preliminary tests demonstrated that some compounds had good herbicidal activity. Crop safety tests revealed that compound III-29 was safer than the commercial herbicide mesotrione in wheat and peanuts. Moreover, the compound exhibited the highest inhibitory activity against Arabidopsis thaliana HPPD (AtHPPD), with a half-maximal inhibitory concentration of 0.19 µM, demonstrating superior activity compared with mesotrione (0.28 µM) in vitro. A three-dimensional quantitative structure-activity relationship study revealed that the introduction of smaller groups to the 5-position of cyclohexanedione and negative charges to the 3-position of the benzene ring enhanced the herbicidal activity. A molecular structure comparison demonstrated that compound III-29 was beneficial to plant absorption and conduction. Molecular docking and molecular dynamics simulations further verified the stability of the complex formed by compound III-29 and AtHPPD. Thus, this study may provide insights into the development of green and efficient herbicides.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase , Arabidopsis , Desenho de Fármacos , Inibidores Enzimáticos , Herbicidas , Simulação de Acoplamento Molecular , Herbicidas/química , Herbicidas/farmacologia , Herbicidas/síntese química , 4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , 4-Hidroxifenilpiruvato Dioxigenase/química , 4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Relação Estrutura-Atividade , Estrutura Molecular , Cetonas/química , Cetonas/farmacologia , Cetonas/síntese química , Cicloexanonas/química , Cicloexanonas/farmacologia , Cicloexanonas/síntese química , Triticum/química , Proteínas de Arabidopsis/antagonistas & inibidores , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo
6.
Sci Total Environ ; 931: 172885, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697546

RESUMO

Nanobubble (NB) technology has gained popularity in the environmental field owing to its distinctive characteristics and ecological safety. More recently, the application of NB technology in anaerobic digestion (AD) systems has been proven to promote substrate degradation and boost the production of biogas (H2 and/or CH4). This review presents the recent advancements in the application of NB technology in AD systems. Meanwhile, it also sheds light on the underlying mechanisms of NB technology that contribute to the enhanced biogas production from AD of organic solid wastes. Specifically, the working principles of the NB generator are first summarized, and then the structure of the NB generator is optimized to accommodate the demand for NB characteristics in the AD system. Subsequently, it delves into a detailed discussion of how the addition of nanobubble water (NBW) affects AD performance and the different factors that NB can potentially contribute. As a simple and environmentally friendly additive, NBW was commonly used in the AD process to enhance the fluidity and mass transfer characteristics of digestate. Additionally, NB has the potential to enhance the functionality of different types of microbial enzymes that play crucial roles in the AD process. This includes boosting extracellular hydrolase activities, optimizing coenzyme F420, and improving cellulase function. Finally, it is proposed that NBW has development potential for the pretreatment of substrate and inoculum, with future development being directed towards this aim.


Assuntos
Biocombustíveis , Eliminação de Resíduos , Anaerobiose , Eliminação de Resíduos/métodos , Resíduos Sólidos , Reatores Biológicos
7.
Food Chem ; 452: 139533, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38705119

RESUMO

Encapsulating enzymes in metal-organic frameworks is a common practice to improve enzyme stability against harsh conditions. However, the synthesis of enzyme@MOFs has been primarily limited to small-scale laboratory settings, hampering their industrial applications. Spray drying is a scalable and cost-effective technology, which has been frequently used in industry for large-scale productions. Despite these advantages, its potential for encapsulating enzymes in MOFs remains largely unexplored, due to challenges such as nozzle clogging from MOF particle formation, utilization of toxic organic solvents, controlled release of encapsulated enzymes, and high temperatures that could compromise enzyme activity. Herein, we present a novel approach for preparing phytase@MIL-88 A using solvent-free spray drying. This involves atomizing two MOF precursor solutions separately using a three-fluid nozzle, with enzyme release controlled by manipulating defects within the MOFs. The physicochemical properties of the spray dried particles are characterized using X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Leveraging the efficiency and scalability of spray drying in industrial production, this scalable encapsulation technique holds considerable promise for broad industrial applications.

8.
J Cell Mol Med ; 28(9): e18351, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693854

RESUMO

Coronary artery bypass grafting (CABG) is an effective treatment for coronary heart disease, with vascular transplantation as the key procedure. Intimal hyperplasia (IH) gradually leads to vascular stenosis, seriously affecting the curative effect of CABG. Mesenchymal stem cells (MSCs) were used to alleviate IH, but the effect was not satisfactory. This work aimed to investigate whether lncRNA MIR155HG could improve the efficacy of MSCs in the treatment of IH and to elucidate the role of the competing endogenous RNA (ceRNA). The effect of MIR155HG on MSCs function was investigated, while the proteins involved were assessed. IH was detected by HE and Van Gieson staining. miRNAs as the target of lncRNA were selected by bioinformatics analysis. qRT-PCR and dual-luciferase reporter assay were performed to verify the binding sites of lncRNA-miRNA. The apoptosis, Elisa and tube formation assay revealed the effect of ceRNA on the endothelial protection of MIR155HG-MSCs. We observed that MIR155HG improved the effect of MSCs on IH by promoting viability and migration. MIR155HG worked as a sponge for miR-205. MIR155HG/miR-205 significantly improved the function of MSCs, avoiding apoptosis and inducing angiogenesis. The improved therapeutic effects of MSCs on IH might be due to the ceRNA role of MIR155HG/miR-205.


Assuntos
Apoptose , Hiperplasia , Células-Tronco Mesenquimais , MicroRNAs , RNA Longo não Codificante , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Mesenquimais/metabolismo , Humanos , RNA Longo não Codificante/genética , Apoptose/genética , Movimento Celular/genética , Animais , Transplante de Células-Tronco Mesenquimais/métodos , Túnica Íntima/patologia , Túnica Íntima/metabolismo , Regulação da Expressão Gênica , Proliferação de Células/genética , Masculino , Sobrevivência Celular/genética , RNA Endógeno Competitivo
9.
Bioresour Technol ; 403: 130764, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38718903

RESUMO

Abundant renewable resource lignocellulosic biomass possesses tremendous potential for green biomanufacturing, while its efficient utilization by Yarrowia lipolytica, an attractive biochemical production host, is restricted since the presence of inhibitors furfural and acetic acid in lignocellulosic hydrolysate. Given deficient understanding of inherent interactions between inhibitors and cellular metabolism, sufficiently mining relevant genes is necessary. Herein, 14 novel gene targets were discovered using clustered regularly interspaced short palindromic repeats interference library in Y. lipolytica, achieving tolerance to 0.35 % (v/v) acetic acid (the highest concentration reported in Y. lipolytica), 4.8 mM furfural, or a combination of 2.4 mM furfural and 0.15 % (v/v) acetic acid. The tolerance mechanism might involve improvement of cell division and decrease of reactive oxygen species level. Transcriptional repression of effective gene targets still enabled tolerance when xylose was a carbon source. This work forms a robust foundation for improving microbial tolerance to lignocellulose-derived inhibitors and revealing underlying mechanism.

10.
Animal Model Exp Med ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720455

RESUMO

BACKGROUND: Osteoarthritis (OA) is a common joint disease, and existing drugs cannot cure OA, so there is an urgent need to identify new targets. Mitophagy plays an important role in OA; however, the role of mitophagy in the OA immune system is not yet clear. METHODS: In this study, differential analysis and enrichment analysis were used to identify mitophagy-related genes (MRGs) with differential expression in OA and the functional pathways involved in OA. Subsequently, two machine learning methods, RF and LASSO, were used to screen MRGs with diagnostic value and construct nomograms. At the same time, the relationship between mitophagy and OA immune response was explored by immunoinfiltration analysis. RESULTS: Forty-three differentially MRGs were identified in OA, of which six MRGs (GABARAPL2, PARL, GABARAPL1, JUN, RRAS, and SNX7) were associated with the diagnosis of OA. The ROC analysis results show that these 6 MRGs have high predictive accuracy in the diagnosis of OA. In immune infiltration analysis, we found that the abundance of significantly different immune cells in OA was mostly upregulated. In addition, the expression of diagnostic-related MRGs is correlated with changes in the abundance of immune cells in OA. CONCLUSION: This study demonstrates that six MRGs can be used as diagnostic biomarkers. The expression of diagnostic-related MRGs is correlated with changes in the abundance of immune cells in OA. At the same time, mitophagy may affect the immune microenvironment of OA by regulating immune cells, ultimately leading to the progression of OA.

11.
Neuroendocrinology ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565081

RESUMO

INTRODUCTION: Growth hormone (GH) secreting pituitary adenoma is considered one of the most harmful types of Pituitary Neuroendocrine Tumors (PitNETs). Our previous research has found that high expression of Lysine Methyltransferase 5A (KMT5A) is closely related to the proliferation of PitNETs. The aim of this study was to investigate the role and molecular mechanism of KMT5A in the progression of GH PitNETs. METHODS: Immunohistochemistry, qRT-PCR and Western blot (WB) were used to assess the expression levels of KMT5A in human normal pituitary and GH PitNETs, as well as in rat normal pituitary and GH3 cells. Additionally, we utilized RNA interference technology and treatment with a selective KMT5A inhibitor to decrease the expression of KMT5A in GH3 cells. CCK-8, EdU, Flow cytometry (FCM), clone formation, and WB assay were further employed to evaluate the impact of KMT5A on the proliferation of GH3 cells in vitro. A xenograft model was established to evaluate the role of KMT5A in GH PitNETs progression in vivo. RESULTS: KMT5A was highly expressed in GH PitNETs and GH3 cells. Moreover, the reduction of KMT5A expression led to inhibited growth of GH PitNETs and increased apoptosis of tumor cells, as indicated by the findings from CCK-8, EdU, clone formation and FCM assays. Additionally, WB analysis identified the Wnt/ß-catenin signaling pathway as a potential mechanism through which KMT5A promotes GH PitNETs progression. CONCLUSION: Our research suggests that KMT5A may facilitate the progression of GH PitNETs via the Wnt/ß-catenin signaling pathway. Therefore, KMT5A may serve as a potential therapeutic target and molecular biomarker for GH PitNETs.

12.
Nano Lett ; 24(15): 4354-4361, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38563599

RESUMO

The recent focus of cancer therapeutics research revolves around modulating the immunosuppressive tumor microenvironment (TME) to enhance efficacy. The tumor stroma, primarily composed of cancer-associated fibroblasts (CAFs), poses significant obstacles to therapeutic penetration, influencing resistance and tumor progression. Reprogramming CAFs into an inactivated state has emerged as a promising strategy, necessitating innovative approaches. This study pioneers the design of a nanoformulation using pioglitazone, a Food and Drug Administration-approved anti-diabetic drug, to reprogram CAFs in the breast cancer TME. Glutathione (GSH)-responsive dendritic mesoporous organosilica nanoparticles loaded with pioglitazone (DMON-P) are designed for the delivery of cargo to the GSH-rich cytosol of CAFs. DMON-P facilitates pioglitazone-mediated CAF reprogramming, enhancing the penetration of doxorubicin (Dox), a therapeutic drug. Treatment with DMON-P results in the downregulation of CAF biomarkers and inhibits tumor growth through the effective delivery of Dox. This innovative approach holds promise as an alternative strategy for enhancing therapeutic outcomes in CAF-abundant tumors, particularly in breast cancer.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Nanopartículas , Humanos , Feminino , Pioglitazona/farmacologia , Pioglitazona/uso terapêutico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Microambiente Tumoral
13.
Waste Manag ; 182: 44-54, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636125

RESUMO

Pyrolysis can effectively convert waste tires into high-value products. However, the sulfur-containing compounds in pyrolysis oil and gas would significantly reduce the environmental and economic feasibility of this technology. Here, the desulfurization and upgrade of waste tire pyrolysis oil and gas were performed by adding different metal oxides (Fe2O3, CuO, and CaO). Results showed that Fe2O3 exhibited the highest removal efficiency of 87.7 % for the sulfur-containing gas at 600 °C with an outstanding removal efficiency of 99.5 % for H2S. CuO and CaO were slightly inferior to Fe2O3, with desulfurization efficiencies of 75.9 % and 45.2 % in the gas when added at 5 %. Fe2O3 also demonstrated a notable efficacy in eliminating benzothiophene, the most abundant sulfur compound in pyrolysis oil, with a removal efficiency of 78.1 %. Molecular dynamics simulations and experiments showed that the desulfurization mechanism of Fe2O3 involved the bonding of Fe-S, the breakage of C-S, dehydrogenation and oxygen migration process, which promoted the conversion of Fe2O3 to FeO, FeS and Fe2(SO4)3. Meanwhile, Fe2O3 enhanced the cyclization and dehydrogenation reaction, facilitating the upgrade of oil and gas (monocyclic aromatics to 57.4 % and H2 to 22.3 %). This study may be helpful for the clean and high-value conversion of waste tires.


Assuntos
Óxidos , Pirólise , Óxidos/química , Enxofre/química , Incineração/métodos , Compostos Férricos/química , Gases/química , Borracha/química , Compostos de Cálcio/química , Cobre
14.
Cancer Invest ; 42(3): 226-242, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38616304

RESUMO

Chronic inflammation promotes the development of pancreatic ductal adenocarcinoma (PDAC) and PDAC-related inflammatory tumor microenvironment facilitates tumor growth and metastasis. Thus, we aimed to study the association between inflammatory response and prognosis in patients with PDAC. We conducted the whole transcriptomic sequencing using tissue samples collected from patients diagnosed with PDAC (n = 106) recruited from Shandong Cancer Hospital. We first constructed a prognostic signature using 15 inflammation-related genes in The Cancer Genome Atlas (TCGA) cohort (n = 177) and further validated it in an independent International Cancer Genome Consortium (ICGC) cohort (n = 90) and our in-house cohort. PDAC patients with a higher risk score had poorer overall survival (OS) (P < 0.001; HR, 3.02; 95% CI, 1.94-4.70). The association between the prognostic signature and OS remained significant in the multivariable Cox regression adjusting for age, sex, alcohol exposure, diabetes, and stage (P < 0.001; HR, 2.91; 95% CI, 1.73-4.89). This gene signature also robustly predicted prognosis in the ICGC cohort (P = 0.01; HR, 1.94; 95% CI, 1.14-3.30) and our cohort (P < 0.001; HR, 2.40; 95% CI, 1.45-3.97). Immune subtype C3 (inflammatory) was enriched and CD8+ T cells were higher in patients with a lower risk score (P < 0.05). Furthermore, PDAC patients with higher risk scores were more sensitive to chemotherapy, immunotherapy, and PARP inhibitors (P < 0.05). In sum, we identified a novel gene signature that was associated with inflammatory response for risk stratification, prognosis prediction, and therapy guidance in PDAC patients. Future studies are warranted to validate the clinical utility of the signature.


Assuntos
Carcinoma Ductal Pancreático , Inflamação , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Feminino , Masculino , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Prognóstico , Pessoa de Meia-Idade , Inflamação/genética , Idoso , Biomarcadores Tumorais/genética , Transcriptoma , Microambiente Tumoral/genética , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica/métodos
15.
Environ Sci Technol ; 58(17): 7291-7301, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38623940

RESUMO

The environmental dissemination of extracellular antibiotic resistance genes (eARGs) in wastewater and natural water bodies has aroused growing ecological concerns. The coexisting chemical pollutants in water are known to markedly affect the eARGs transfer behaviors of the environmental microbial community, but the detailed interactions and specific impacts remain elusive so far. Here, we revealed a concentration-dependent impact of dimethyl phthalate (DMP) and several other types of phthalate esters (common water pollutants released from plastics) on the natural transformation of eARGs. The DMP exposure at an environmentally relevant concentration (10 µg/L) resulted in a 4.8-times raised transformation frequency of Acinetobacter baylyi but severely suppressed the transformation at a high concentration (1000 µg/L). The promotion by low-concentration DMP was attributed to multiple mechanisms, including increased bacterial mobility and membrane permeability to facilitate eARGs uptake and improved resistance of the DMP-bounded eARGs (via noncovalent interaction) to enzymatic degradation (with suppressed DNase activity). Similar promoting effects of DMP on the eARGs transformation were also found in real wastewater and biofilm systems. In contrast, higher-concentration DMP suppressed the eARGs transformation by disrupting the DNA structure. Our findings highlight a potentially underestimated eARGs spreading in aquatic environments due to the impacts of coexisting chemical pollutants and deepen our understanding of the risks of biological-chemical combined pollution in wastewater and environmental water bodies.


Assuntos
Resistência Microbiana a Medicamentos , Ácidos Ftálicos , Resistência Microbiana a Medicamentos/genética , Águas Residuárias , Biofilmes/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
16.
Biotechnol Bioeng ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555482

RESUMO

The physiological role of Geobacter sulfurreducens extracellular cytochrome filaments is a matter of debate and the development of proposed electronic device applications of cytochrome filaments awaits methods for large-scale cytochrome nanowire production. Functional studies in G. sulfurreducens are stymied by the broad diversity of redox-active proteins on the outer cell surface and the redundancy and plasticity of extracellular electron transport routes. G. sulfurreducens is a poor chassis for producing cytochrome nanowires for electronics because of its slow, low-yield, anaerobic growth. Here we report that filaments of the G. sulfurreducens cytochrome OmcS can be heterologously expressed in Shewanella oneidensis. Multiple lines of evidence demonstrated that a strain of S. oneidensis, expressing the G. sulfurreducens OmcS gene on a plasmid, localized OmcS on the outer cell surface. Atomic force microscopy revealed filaments with the unique morphology of OmcS filaments emanating from cells. Electron transfer to OmcS appeared to require a functional outer-membrane porin-cytochrome conduit. The results suggest that S. oneidensis, which grows rapidly to high culture densities under aerobic conditions, may be suitable for the development of a chassis for producing cytochrome nanowires for electronics applications and may also be a good model microbe for elucidating cytochrome filament function in anaerobic extracellular electron transfer.

17.
Eur J Obstet Gynecol Reprod Biol ; 296: 327-332, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38520955

RESUMO

OBJECTIVE: To validate the accuracy of four early warning scores for early identification of women at risk. METHODS: This was a retrospective study of pregnant women admitted in obstetrics Critical Care Unit (ICU). Capacity of the Modified Obstetric Early Warning Score (MOEWS), ICNARC Obstetric Early Warning Score (OEWS), Maternal Early Obstetric Warning System (MEOWS chart), and Maternal Early Warning Trigger (MEWT) were compared in predicting severe maternal morbidity. Area under receiver operator characteristic (AUROC) curve was used to evaluate the predictive performance of scoring system. RESULTS: A total of 352 pregnant women were enrolled and 290 were identified with severe maternal morbidity. MOEWS was more sensitive than MEOWS chart, ICNARC OEWS and MEWT (96.9 % vs. 83.4 %, 66.6 % and 44.8 %). MEWT had the highest specificity (98.4 %), followed by MOEWS (83.9 %), ICNARC OEWS (75.8 %) and MEOWS chart (48.4 %). AUROC of MOEWS, ICNARC OEWS, MEOWS chart, and MEWT for prediction of maternal mortality were 0.91 (95 % CI: 0.874-0.945), 0.765(95 % CI: 0.71-0.82), 0.657(95 % CI: 0.577-0.738), and 0.716 (95 % CI, 0.659-0.773) respectively. MOEWS had the highest AUCs in the discrimination of serious complications in hypertensive disorders, cardiovascular disease, obstetric hemorrhage and infection. For individual vital signs, maximum diastolic blood pressure (DBP), maximum systolic blood pressure (SBP), maximum respiratory rate (RR) and peripheral oxygen saturation (SPO2) demonstrated greater predictive ability. CONCLUSION: MOEWS is more accurate than ICNARC OEWS, MEOWS chart, and MEWT in predicting the deterioration of women. The prediction ability of DBP, SBP, RR and SPO2 are more reliable.


Assuntos
Obstetrícia , Complicações na Gravidez , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Estado Terminal , Complicações na Gravidez/diagnóstico , Pressão Sanguínea
18.
Virol J ; 21(1): 53, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438894

RESUMO

BACKGROUND: Atypical porcine pestivirus (APPV) is a newly discovered swine pestivirus, which can cause congenital tremor and high mortality in newborn piglets and subclinical infection in adult pigs, leading to significant impacts on the pig industry. Currently, there is no approved serological method to assess APPV infection status in pig farms. METHODS: In this study, the envelope glycoprotein E2 of APPV was highly expressed in suspension HEK293 cells, and further an indirect enzyme-linked immunosorbent assay based on the recombinant E2 protein (E2-iELISA) was developed and evaluated. RESULTS: The reaction parameters of the E2-iELISA were optimized, and the cutoff value was determined to be 0.2 by analyzing S/P values of 165 negative sera against APPV that were confirmed by virus neutralization test (VNT). Specificity test showed that the method had no cross-reaction with other common swine viruses. The E2-iELISA was evaluated using a panel of swine sera, and showed high sensitivity (113/120, 94.2%) and specificity (65/70, 92.9%), and the agreement rate with VNT was 93.7% (178/190). Subsequently, the E2-iELISA was utilized to investigate the seroprevalence of APPV in pig herds of China. When detecting 1368 pig serum samples collected from nine provinces in China, the overall seroprevalence of APPV was 73.9% (1011/1368). CONCLUSION: Our findings suggest that the E2-iELISA is specific and sensitive, and could be a valuable tool for serological surveillance of APPV infection in pigs.


Assuntos
Infecções Assintomáticas , Pestivirus , Humanos , Adulto , Animais , Suínos , Células HEK293 , Estudos Soroepidemiológicos , Ensaio de Imunoadsorção Enzimática
19.
ACS Appl Mater Interfaces ; 16(14): 17766-17777, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38534058

RESUMO

Serving as neuromorphic hardware accelerators, memristors play a crucial role in large-scale neuromorphic computing. Herein, two-terminal memristors utilizing amorphous indium-gallium-zinc oxide (a-IGZO) are fabricated through room-temperature sputtering. The electrical characteristics of these memristors are effectively modulated by varying the oxygen flow during the deposition process. The optimized a-IGZO memristor, fabricated under 3 sccm oxygen flow, presents a 5 × 103 ratio between its high- and low-resistance states, which can be maintained over 1 × 104 s with minimal degradation. Meanwhile, desirable properties such as electroforming-free and self-compliance, crucial for low-energy consumption, are also obtained in the a-IGZO memristor. Moreover, analog conductance switching is observed, demonstrating an interface-type behavior, as evidenced by its device-size-dependent performance. The coexistence of negative differential resistance with analog switching is attributed to the migration of oxygen vacancies and the trapping/detrapping of charges. Furthermore, the device demonstrates optical storage capabilities by exploiting the optical properties of a-IGZO, which can stably operate for up to 50 sweep cycles. Various synaptic functions have been demonstrated, including paired-pulse facilitation and spike-timing-dependent plasticity. These functionalities contribute to a simulated recognition accuracy of 90% for handwritten digits. Importantly, a one-selector one-memristor (1S1M) architecture is successfully constructed at room temperature by integrating a-IGZO memristor on a TaOx-based selector. This architecture exhibits a 107 on/off ratio, demonstrating its potential to suppress sneak currents among adjacent units in a memristor crossbar.

20.
J Org Chem ; 89(7): 4971-4978, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38509452

RESUMO

A streamlined and efficient approach to the key epoxide intermediate for the asymmetric synthesis of triazole antifungal agents is presented. This synthesis highlights a P(NMe2)3-mediated nonylidic olefination of α-keto ester, ensuring the exclusive formation of the requisite (Z)-alkene, followed by a highly enantioselective Jacobsen epoxidation to establish the two vicinal stereocenters in a single step. The versatility of this strategy is exemplified through the efficient synthesis of efinaconazole and ravuconazole.


Assuntos
Antifúngicos , Compostos de Epóxi , Antifúngicos/farmacologia , Estereoisomerismo , Alcenos , Triazóis
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