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1.
J Environ Sci (China) ; 150: 36-53, 2025 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39306411

RESUMEN

The global concern surrounding the advancement of methods for treating wastewater and polluted soil has markedly increased over time. While electrochemical advanced oxidation processes (EAOPs) and biotreatments are commonly employed technologies for remediating wastewater and polluted soil, their widespread adoption is hindered by their limitations, which include high costs associated with EAOPs and prolonged remediation time of biotreatments. In the review, we provided an overview of EAOP technology and biotreatment, emphasizing the critical aspects involved in building a combined system. This review systematically evaluates recent research that combines EAOPs with bioremediation for treating wastewater or contaminated soil as pretreatment or post-treatment process. Research findings suggest that the combined treatment method represents a promising and competitive technology that can overcome some of the limitations of individual treatments. Additionally, we discussed the potential applications of this technology in varying levels of wastewater and soil pollution, as well as the underlying combination mechanisms.


Asunto(s)
Biodegradación Ambiental , Restauración y Remediación Ambiental , Oxidación-Reducción , Contaminantes del Suelo , Eliminación de Residuos Líquidos , Aguas Residuales , Aguas Residuales/química , Contaminantes del Suelo/análisis , Eliminación de Residuos Líquidos/métodos , Restauración y Remediación Ambiental/métodos , Técnicas Electroquímicas/métodos , Suelo/química
2.
Bioresour Technol ; 414: 131556, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39357610

RESUMEN

Polyethylene terephthalate (PET) biodegradation is hindered by the intermediates bis (2-hydroxyethyl) terephthalate (BHET) and mono (2-hydroxyethyl) terephthalate (MHET). BMHETase, a thermophilic hydrolase identified from the UniParc database, exhibits degradation activity towards both BHET and MHET. BMHETase showed higher activity on BHET than LCCICCG and FASTPETase at temperatures ranging from 50 to 70℃. To enhance its activity in degrading MHET, BMHETase was engineered to mimic Ideonella sakaiensis MHETase. The resulting 6-point mutant's activities on MHET and BHET were 8 and 2 times those of the WT, with both optimal temperatures increased by 5℃. This enhancement may be attributed to the BMHETase6M's intensified binding ability with MHET and enlarged binding pocket. When combined with LCCICCG, BMHETase6M achieved complete degradation of MHET in PET films to terephthalic acid, indicating broad application potential. These findings suggest that BMHETase6M holds promise as a candidate for enhancing PET biodegradation efficiency and plastic waste management.

3.
J Ethnopharmacol ; 337(Pt 2): 118876, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39362325

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Rosa odorata Sweet var. gigantea (Coll. et Hemsl.) Rehd. et Wils is a commonly utilized traditional medicine among the Yi nationality, also known as "Gugongguo", for the treatment of gastrointestinal disorders. Previous studies have indicated that the extract of Rosa odorata sweet var. gigantea (FOE) fruit has demonstrated a protective effect on the stomach; however, its impact on chronic atrophic gastritis (CAG) with severe disease remains unknown. AIM OF THE STUDY: This study aimed to investigate the impact of FOE on CAG and its underlying mechanisms both in vitro and in vivo. MATERIALS AND METHODS: By employing Ultra Performance Liquid Chromatography/Quadrupole-Time of Flight Mass Spectrometry (UPLC-QTOF-MS/MS) and network pharmacology, the primary active compounds and action targets of FOE were identified. In vitro, the impact of FOE on CAG was investigated through scratch, migration, and invasion assays. Subsequently, guided by network pharmacology, EMT and TGF-ß signaling pathway-related proteins were assessed using Western blot and immunofluorescence experiments. Additionally, an in vivo CAG rat model was established to validate the effects of FOE and confirm its mechanism of action through hematoxylin-eosin (H&E), immunohistochemistry, Western blot, as well as untargeted metabolomics analysis of rat serum. It was observed that FOE inhibited scratch healing abilities, migration, invasion capabilities, as well as the expression of EMT-related proteins (E-cadherin, N-cadherin, Snail, Vimentin) in CAG model cells (MC cells), providing initial evidence for its efficacy. RESULTS: Through the analysis of UPLC-QTOF-MS/MS, a total of 51 major compounds were identified in the FOE. Subsequent network pharmacological analysis suggested that FOE may regulate Epithelial mesenchymal transition (EMT) through the transforming growth factor ß (TGF-ß) pathway. Furthermore, experimental verification demonstrated that FOE inhibited the protein expression of TGF-ß1 and its downstream protein Smad2/3 in vitro. In vivo findings also indicated similar mechanisms in MC cells, suggesting a reversal of the CAG process and significant inhibition of EMT and TGF-ß signaling pathways. Additionally, untargeted metabolomics of rat serum confirmed the therapeutic effect of FOE on CAG and predicted its potential involvement in the arachidonic acid metabolic pathway. CONCLUSION: This study initially demonstrated that FOE effectively reverses the process of EMT through the TGF-ß1/Smad2/3 signaling pathway, thereby providing a therapeutic benefit for CAG.

4.
Sci Rep ; 14(1): 24872, 2024 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-39438670

RESUMEN

Previous studies have indicated a potential association between the alanine aminotransferase to high-density lipoprotein cholesterol (ALT/HDL-C) ratio and the risk of Type 2 Diabetes Mellitus, but its relation with gestational diabetes mellitus (GDM) remains uncertain. This study aims to investigate the correlation between the ALT/HDL-C ratio in early pregnancy and the risk of GDM. This study is a secondary analysis based on an open-source cohort study. A total of 590 single pregnant women attending two hospitals in Korea up to 14 weeks gestation were included between November 2014 and July 2016. Logistic regression analysis, subgroup analysis, and smooth curve fitting were employed to explore the association between the ALT/HDL-C ratio and GDM risk. The predictive capability of the ALT/HDL-C ratio for GDM was assessed using ROC curve analysis. The average age of participants was 32.06 ± 3.80 years, with a GDM incidence rate of 6.27%. Multifactorial logistic regression analysis revealed that the serum ALT/HDL-C ratio is an independent influencing factor for GDM (OR = 1.08, 95% CI: 1.02-1.16). Furthermore, a non-linear relationship between the ALT/HDL-C ratio and GDM risk was observed, with a turning point at 5.51. The effect size (OR) on the left and right sides of the turning point were 0.75 (95% CI: 0.37-1.59) and 1.55 (95% CI: 1.18-2.00), respectively. Additionally, when combined with age, pre-pregnancy body mass index, parity, and insulin resistance index in a prediction model for GDM, the ALT/HDL-C ratio demonstrated improved sensitivity of prediction by reaching up to 67.6%, specificity of prediction by reaching up to 87.3%, and an area under curve value of 0.819 (95%CI: 0.743-0.894). In early pregnancy, the serum ALT/HDL-C ratio shows a positive correlation with maternal risk in a nonlinear manner. The combination of ALT/HDL-C ratio with maternal characteristics and metabolic indicators provides good predictive value for GDM. This study may facilitate optimization of GDM prevention in pregnant women and enable timely and effective intervention to enhance their prognosis.


Asunto(s)
Alanina Transaminasa , HDL-Colesterol , Diabetes Gestacional , Humanos , Diabetes Gestacional/sangre , Diabetes Gestacional/epidemiología , Femenino , Embarazo , Alanina Transaminasa/sangre , HDL-Colesterol/sangre , Adulto , Factores de Riesgo , Curva ROC , República de Corea/epidemiología , Modelos Logísticos
5.
Comput Biol Med ; 183: 109291, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39461101

RESUMEN

In robot-assisted laminectomy, precise control of touch force on the spinal cord during the dissection of ossified ligaments is critical to prevent dura mater tearing and ensure surgical safety. However, the complex viscoelastic characteristics of tissue at the lesion site pose a significant challenge for accurately applying touch force. This paper proposes a safe touch force servo framework based on tissue model identification and preoperative optimization of the force controller. First, a soft tissue model is established using elastic and viscoelastic elements, and the transfer function from tissue deformation to touch force is derived. Subsequently, the path and parameters of a safe pre-touch are designed, and force information required for tissue model identification is obtained through the pre-touch experiment. The model order and specific parameter values are then identified using a differential evolution algorithm. Next, force control simulation is conducted based on the identified model, and a specifically designed loss function is introduced to achieve preoperative tuning of the force controller. Finally, step force control experiments on sheep spines validate the effectiveness of the proposed method. This paper provides a safe and available touch motion control framework that can be expandable to impose precise force on various vulnerable soft tissues, with the potential for widespread application.

7.
Microbiol Res ; 289: 127908, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39321593

RESUMEN

The potential of seed endophytic microbes to enhance plant growth and resilience is well recognized, yet their role in alleviating cold stress in rice remains underexplored due to the complexity of these microbial communities. In this study, we investigated the diversity of seed endophytic microbes in two rice varieties, the cold-sensitive CB9 and the cold-tolerant JG117. Our results revealed significant differences in the abundance of Microbacteriaceae, with JG117 exhibiting a higher abundance under both cold stress and room temperature conditions compared to CB9. Further analysis led to the identification of a specific cold-tolerant microbe, Microbacterium testaceum M15, in JG117 seeds. M15-inoculated CB9 plants showed enhanced growth and cold tolerance, with a germination rate increase from 40 % to 56.67 % at 14℃ and a survival rate under cold stress (4℃) doubling from 22.67 % to 66.67 %. Additionally, M15 significantly boosted chlorophyll content by over 30 %, increased total protein by 16.31 %, reduced malondialdehyde (MDA) levels by 37.76 %, and increased catalase activity by 26.15 %. Overall, our study highlights the potential of beneficial endophytic microbes like M. testaceum M15 in improving cold tolerance in rice, which could have implications for sustainable agricultural practices and increased crop productivity in cold-prone regions.

8.
BMC Cardiovasc Disord ; 24(1): 502, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300362

RESUMEN

BACKGROUND: The post-processing technology of CTA offers significant advantages in evaluating left atrial enlargement (LAE) in patients with persistent atrial fibrillation (PAF). This study aims to identify parameters for rapidly and accurately diagnosing LAE in patients with PAF using CT cross-sections. METHODS: Left atrial pulmonary venous (PV) CT was performed to 300 PAF patients with dual-source CT, and left atrial volume (LAV), left atrial anteroposterior diameter (LAD1), left atrial transverse diameter (LAD2), and left atrial area (LAA) were measured in the ventricular end systolic (ES) and middle diastolic (MD). LA index (LAI) = LA parameter/body surface area (BSA). Left atrial volume index (LAVIES) > 77.7 ml/m2 was used as the reference standard for the LAE diagnosis. RESULTS: 227 patients were enrolled in the group, 101 (44.5%) of whom had LAE. LAVES and LAVMD (r = 0.983), LAVIES and LAVIMD (r = 0.984), LAAES and LAVIES (r = 0.817), LAAMD and LAVIES (r = 0.814) had strong positive correlations. The area under curve (AUC) showed that all measured parameters were suitable for diagnosing LAE, and the diagnostic efficacy was compared as follows: LAA/LAAI> LAD> the relative value index of LAD, LAD2> LAD1. LAA and LAAI demonstrated comparable diagnostic efficacy, with LAA being more readily available than LAAI. CONCLUSIONS: The axial LAA measured by CTA can be served as a parameter for the rapid and accurate diagnosis of LAE in patients with PAF.


Asunto(s)
Fibrilación Atrial , Angiografía por Tomografía Computarizada , Atrios Cardíacos , Valor Predictivo de las Pruebas , Humanos , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Femenino , Masculino , Persona de Mediana Edad , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Anciano , Reproducibilidad de los Resultados , Función del Atrio Izquierdo , Remodelación Atrial , Estudios Retrospectivos , Cardiomegalia/diagnóstico por imagen , Tomografía Computarizada Multidetector , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/fisiopatología
9.
Artículo en Inglés | MEDLINE | ID: mdl-39258770

RESUMEN

Objective: This meta-analysis aimed to compare the effect of the real-time continuous glucose monitoring (rt-CGM) and flash glucose monitoring (FGM) on glycemic control in adults with type 1 diabetes mellitus (T1DM). Methods: A systematic literature search of all relevant studies comparing the clinical effectiveness of rt-CGM and FGM in adults with T1DM on Cochrane Library, PubMed, Embase, Web of Science, and Scopus from January 2015 to June 2023 was performed. The primary endpoints were glycated hemoglobin (HbA1c) and TIR (time in range). Secondary endpoints included time below range [TBR (<3.9 mmol/L) and (<3.0 mmol/L)], time above range [TAR (>10.0 mmol/L) and (>13.9 mmol/L)], mean glucose, and glycemic variability (GV) [standard deviations (SD) and coefficient of variation (CV)]. Results: Six studies with 1516 TIDM patients, including three randomized controlled trials and three observational studies, were enrolled in this meta-analysis. Compared to FGM, rt-CGM led to greater glycemic control, represented by higher TIR (%, 3.9 ∼ 10 mmol/L) (SMD = 0.59, 95%CI: 0.37 ∼ 0.81, p < 0.001), decreased TBR (%, <3.9 mmol/L) (SMD = -1.45, 95%CI: -2.33 ∼ -0.57, p = 0.001), decreased TAR [(%, >10.0 mmol/L) (SMD = -0.38, 95%CI: -0.71 ∼ -0.04, p = 0.03) and (%, >13.9 mmol/L) (SMD = -0.42, 95%CI: -0.79 ∼ -0.04, p = 0.03), respectively], lower mean glucose (SMD = -0.18, 95%CI: -0.31 ∼ -0.06, p = 0.003), decreased SD (SMD = -0.70, 95%CI: -1.09 ∼ -0.31, p < 0.001), and decreased CV (SMD = -0.76, 95%CI: -1.05 ∼ -0.47, p < 0.001). However, there was no difference in lowering HbA1c and TBR (%, <3.0 mmol/L) between groups. Conclusion: The rt-CGM outperformed FGM in improving several key CGM metrics among adults with T1DM, but there is no significant difference in HbA1c and TBR (<3.0 mmol/L).

10.
BMC Public Health ; 24(1): 2648, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39334108

RESUMEN

BACKGROUND: Accumulating evidence suggests that exposure to air pollution acts as a potential trigger for neurological diseases (NDs), yet the current knowledge regarding the impact of ambient nitrogen dioxide (NO2) on the patients with NDs remains limited. In this study, we conducted a time-series study to evaluate the association between short-term exposure to NO2 and hospital visits for NDs in Xinxiang, China. METHODS: An over-dispersed Poisson generalized additive model was used to analyze the association between ambient NO2 concentrations and daily outpatient visits for NDs from January 1, 2015 to December 31, 2017. The model adjusted for meteorological factors, temporal trends, day of the week, and public holidays. The concentrations of air pollutants were collected from four air quality stations in Xinxiang. RESULTS: A total of 38, 865 outpatient visits for NDs were retrieved during the study period. 86.5% of the patients were below the age of 65 years. It was revealed that a 10 µg/m3 increase in NO2 at lag 0 was associated with a significant rise of 1.50% (95% CI: 0.45-2.56%) in outpatient visits for NDs, which was stronger during the cold season. However, the overall results from stratified analyses did not reach statistical significance. CONCLUSIONS: Short-term exposure to NO2 is associated with increased outpatient visits for NDs. These findings underscore the need for implementing mitigating measures to reduce the neurological health effects of air pollutants.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Enfermedades del Sistema Nervioso , Dióxido de Nitrógeno , Humanos , Dióxido de Nitrógeno/análisis , Dióxido de Nitrógeno/efectos adversos , China/epidemiología , Enfermedades del Sistema Nervioso/inducido químicamente , Persona de Mediana Edad , Anciano , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Masculino , Femenino , Adulto , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Adolescente , Adulto Joven , Atención Ambulatoria/estadística & datos numéricos , Pacientes Ambulatorios/estadística & datos numéricos , Estaciones del Año , Niño
11.
Adv Sci (Weinh) ; : e2402441, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39308285

RESUMEN

Understanding the mechanism underlying thermostabilization in naturally stable enzymes and enhancing the thermostability of unstable enzymes are crucial aspects in enzyme engineering. Despite the development of various engineering methods, there remains substantial scope for improvement. In this study, a novel concept termed as the "short board" theory is proposed, which conceptualizes proteins as barrels with each component representing a jagged board. Notably, optimizing modifications to the shortest board yields optimal enhancements in terms of thermostability performance. To validate this theory, α-amylase, an industrial bulk enzyme with multiple domains, is employed as a model enzyme. The existence of "short boards" and their impact on thermostability modification are demonstrated at the domain, residue, and atomic levels through experimental confirmation using domain substitution. Furthermore, a novel thermostable design and prediction model called Zero-Shot Hamiltonian (ZSH) is established and evaluated on α-amylase. This coevolutionary approach based on thermostability and deep learning exhibits remarkable success exclusively when applied to enzymes with fixed short boards. The integration of the "short board" theory with the ZSH model presents an innovative tool for enhancing enzymatic thermostability.

12.
J Affect Disord ; 367: 668-677, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39236888

RESUMEN

BACKGROUND: Many studies have shown that the COVID-19 pandemic has increased the risk of suicidal tendencies among the public. However, there is limited research reporting on the changing trends in suicidal ideation after 2020 in the context of the long-term normalization of COVID-19 prevention and control measures in China. METHODS: The self-administered online questionnaire was adopted to collect 12-month suicidal ideation, depressive symptoms, anxiety symptoms, stress, and some demographic information from university students by convenient cluster sampling in Shandong, Shaanxi, and Jilin Provinces, China. Multivariate logistic regressions were performed to assess the association between different factors and suicidal ideation. RESULTS: The prevalence of 12-month suicidal ideation from 2021 to 2023 among university students was 3.89 %, 5.81 %, and 4.33 %, respectively, showing a trend of first increasing and then decreasing. The trends presented a similar tendency in the subgroups according to gender, majors, and grades, except among urban freshman-year students. The associated factors of suicidal ideation were different among university students in different surveys. However, female gender, poor mental health, and depressive symptoms were linked to a higher risk of suicidal ideation. LIMITATIONS: More representative large-scale longitudinal studies should be used to monitor the suicidal behavior of university students. CONCLUSIONS: The prevalence of 12-month suicidal ideation among Chinese university students exhibited a pattern of initial increase followed by a subsequent decrease from 2021 to 2023. Despite the complete lifting of COVID-19 prevention and control measures in China, the prolonged three-year epidemic may have enduring adverse effects on university students, underscoring the ongoing importance of providing continuous mental health services to this population.


Asunto(s)
COVID-19 , Depresión , Estudiantes , Ideación Suicida , Humanos , China/epidemiología , Femenino , Masculino , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Estudios Transversales , Prevalencia , Universidades , COVID-19/epidemiología , COVID-19/psicología , COVID-19/prevención & control , Adulto Joven , Depresión/epidemiología , Depresión/psicología , Adulto , Factores de Riesgo , Ansiedad/epidemiología , Ansiedad/psicología , Adolescente , Encuestas y Cuestionarios , SARS-CoV-2
13.
Molecules ; 29(15)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39125076

RESUMEN

Various copper-related defects in the absorption layer have been a key factor impeding the enhancement of the efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. Alkali metal doping is considered to be a good strategy to ameliorate this problem. In this article, Rb-doped CZTSSe (RCZTSSe) thin films were synthesized using the sol-gel technique. The results show that the Rb atom could successfully enter into the CZTSSe lattice and replace the Cu atom. According to SEM results, a moderate amount of Rb doping aided in enhancing the growth of grains in CZTSSe thin films. It was proven that the RCZTSSe thin film had the densest surface morphology and the fewest holes when the doping content of Rb was 2%. In addition, Rb doping successfully inhibited the formation of CuZn defects and correlative defect clusters and promoted the electrical properties of RCZTSSe thin films. Finally, a remarkable power conversion efficiency of 7.32% was attained by the champion RCZTSSe device with a Rb content of 2%. Compared with that of un-doped CZTSSe, the efficiency improved by over 30%. This study offers new insights into the influence of alkali metal doping on suppressing copper-related defects and also presents a viable approach for improving the efficiency of CZTSSe devices.

14.
J Anim Sci Biotechnol ; 15(1): 106, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39103958

RESUMEN

BACKGROUND: The intestinal barrier is the first line of defense against intestinal invasion by pathogens and foreign antigens and is closely associated with the gut microbiota. Astragalus polysaccharides (APS) have a long history of use in traditional Chinese medicine owing to its protective properties against intestinal barrier function. The mechanism of APS-induced gut microbiota enhancing intestinal barrier function is urgently needed. RESULTS: Dietary polysaccharide deprivation induced intestinal barrier dysfunction, decreased growth performance, altered microbial composition (Faecalibacterium, Dorea, and Coprobacillus), and reduced isobutyrate concentration. The results showed that APS facilitates intestinal barrier function in broiler chickens, including a thicker mucus layer, reduced crypt depth, and the growth of tight junction proteins. We studied the landscape of APS-induced gut microbiota and found that APS selectively promoted the growth of Parabacteroides, a commensal bacterium that plays a predominant role in enhancing intestinal barrier function. An in vitro growth assay further verified that APS selectively increased the abundance of Parabacteroides distasonis and Bacteroides uniformis. Dietary APS supplementation increased the concentrations of isobutyrate and bile acid (mainly chenodeoxycholic acid and deoxycholate acid) and activated signaling pathways related to intestinal barrier function (such as protein processing in the endoplasmic reticulum, tight junctions, and adherens junction signaling pathways). CONCLUSIONS: APS intervention restored the dietary polysaccharide-induced dysfunction of the intestinal barrier by selectively promoting the abundance of Parabacteroides distasonis, and increasing the concentrations of isobutyrate and bile acids (mainly CDCA and DCA). These findings suggest that APS-induced gut microbiota and metabolic niches are promising strategies for enhancing intestinal barrier function.

15.
Front Pharmacol ; 15: 1421499, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39119611

RESUMEN

Melasma, a prevalent pigmentary disorder, is characterized by its complex etiology, propensity for recurrence, and resistance to treatment. However, there is currently no research on melasma through bibliometrics and visualisation. This study analyses the hotspots and trends in the field based on 2,709 publications from the Web of Science Core Collection (WOSCC). We carried out bibliometric analyses using Citespace software for different countries/regions, institutions, authors, and keywords. References were also analysed using VoSviewer. The results indicate that overall, there has been an increase in publications related to melasma since 2014. According to the analysis of the collaborative network diagram, the United States, Egyptian Knowledge Bank, and Benjakul Soottawat are the most contributing countries, institutions, and authors, respectively. Reference and keyword analyses have identified the pathogenesis and treatment of melasma as a prevalent topic in recent years. And how to find new treatment options and more effective therapeutic drugs is a future research trend. This is the first bibliometric and visual analysis of melasma-related literature to explore research hotspots and trends.

17.
Microb Cell Fact ; 23(1): 233, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174991

RESUMEN

BACKGROUND: Methyl methacrylate (MMA) is a key precursor of polymethyl methacrylate, extensively used as a transparent thermoplastic in various industries. Conventional MMA production poses health and environmental risks; hence, citramalate serves as an alternative bacterial compound precursor for MMA production. The highest citramalate titer was previously achieved by Escherichia coli BW25113. However, studies on further improving citramalate production through metabolic engineering are limited, and phage contamination is a persistent problem in E. coli fermentation. RESULTS: This study aimed to construct a phage-resistant E. coli BW25113 strain capable of producing high citramalate titers from glucose. First, promoters and heterologous cimA genes were screened, and an effective biosynthetic pathway for citramalate was established by overexpressing MjcimA3.7, a mutated cimA gene from Methanococcus jannaschii, regulated by the BBa_J23100 promoter in E. coli. Subsequently, a phage-resistant E. coli strain was engineered by integrating the Ssp defense system into the genome and mutating key components of the phage infection cycle. Then, the strain was engineered to include the non-oxidative glycolysis pathway while removing the acetate synthesis pathway to enhance the supply of acetyl-CoA. Furthermore, glucose utilization by the strain improved, thereby increasing citramalate production. Ultimately, 110.2 g/L of citramalate was obtained after 80 h fed-batch fermentation. The citramalate yield from glucose and productivity were 0.4 g/g glucose and 1.4 g/(L·h), respectively. CONCLUSION: This is the highest reported citramalate titer and productivity in E. coli without the addition of expensive yeast extract and additional induction in fed-bath fermentation, emphasizing its potential for practical applications in producing citramalate and its derivatives.


Asunto(s)
Escherichia coli , Fermentación , Glucosa , Glucólisis , Ingeniería Metabólica , Escherichia coli/metabolismo , Escherichia coli/genética , Ingeniería Metabólica/métodos , Glucosa/metabolismo , Vías Biosintéticas , Regiones Promotoras Genéticas , Malatos
18.
Phys Med Biol ; 69(18)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39151463

RESUMEN

Objective.Optical coherence tomography (OCT) is widely used in clinical practice for its non-invasive, high-resolution imaging capabilities. However, speckle noise inherent to its low coherence principle can degrade image quality and compromise diagnostic accuracy. While deep learning methods have shown promise in reducing speckle noise, obtaining well-registered image pairs remains challenging, leading to the development of unpaired methods. Despite their potential, existing unpaired methods suffer from redundancy in network structures or interaction mechanisms. Therefore, a more streamlined method for unpaired OCT denoising is essential.Approach.In this work, we propose a novel unpaired method for OCT image denoising, referred to as noise-imitation learning (NIL). NIL comprises three primary modules: the noise extraction module, which extracts noise features by denoising noisy images; the noise imitation module, which synthesizes noisy images and generates fake clean images; and the adversarial learning module, which differentiates between real and fake clean images through adversarial training. The complexity of NIL is significantly lower than that of previous unpaired methods, utilizing only one generator and one discriminator for training.Main results.By efficiently fusing unpaired images and employing adversarial training, NIL can extract more speckle noise information to enhance denoising performance. Building on NIL, we propose an OCT image denoising pipeline, NIL-NAFNet. This pipeline achieved PSNR, SSIM, and RMSE values of 31.27 dB, 0.865, and 7.00, respectively, on the PKU37 dataset. Extensive experiments suggest that our method outperforms state-of-the-art unpaired methods both qualitatively and quantitatively.Significance.These findings indicate that the proposed NIL is a simple yet effective method for unpaired OCT speckle noise reduction. The OCT denoising pipeline based on NIL demonstrates exceptional performance and efficiency. By addressing speckle noise without requiring well-registered image pairs, this method can enhance image quality and diagnostic accuracy in clinical practice.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Relación Señal-Ruido , Tomografía de Coherencia Óptica , Tomografía de Coherencia Óptica/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Humanos
19.
Int J Biol Macromol ; 279(Pt 3): 135184, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39216579

RESUMEN

This work demonstrated an innovative antimicrobial and biodegradable food packaging film CBDA-10-SA which was prepared by crosslinking a natural polyphenolic truxillic acid (cyclobutane-dicarboxylic acid, CBDA-10) and sodium alginate (SA). The CBDA-10-SA film exhibited improved tensile strength (148 MPa) and UV shielding capabilities. The maximum thermal decomposition temperature was achieved of 249 °C. Compared to SA film, CBDA-10-SA showed increased antibacterial activities. In food packaging test, the CBDA-10-SA inhibited the rapid growth of potential of hydrogen (pH) value, slowed down the weight loss, reduced total plate count (TPC) value of pork, and delayed the spoilage process of pork. Notably, CBDA-10-SA displayed remarkable degradability in soil, with 60 % degrading in four weeks. In this study, CBDA-10-SA showed enhanced physicochemical and mechanical properties compared to traditional SA film. Those improvements make it anticipated to be used in not only food packaging but also mechanical, pharmaceutical, and agricultural fields.


Asunto(s)
Alginatos , Embalaje de Alimentos , Polifenoles , Embalaje de Alimentos/métodos , Alginatos/química , Polifenoles/química , Polifenoles/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Resistencia a la Tracción , Antiinfecciosos/farmacología , Antiinfecciosos/química , Ácidos Dicarboxílicos/química , Plásticos Biodegradables/química , Plásticos Biodegradables/farmacología
20.
Metabolites ; 14(7)2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-39057677

RESUMEN

To investigate the dynamic changes in hippocampal metabolism after microwave radiation using liquid chromatography in tandem with mass spectrometry/mass spectrometry (LC-MS/MS) and to identify potential biomarkers. Wistar rats were randomly assigned to a sham group and a microwave radiation group. The rats in the microwave radiation group were exposed to 2.856 GHz for 15 min for three times, with 5 min intervals. The rats in the sham group were not exposed. Transmission electron microscope revealed blurring of the synaptic cleft and postsynaptic dense thickening in hippocampal neurons after microwave radiation. Metabolomic analysis revealed 38, 24, and 39 differentially abundant metabolites at 3, 7, and 14 days after radiation, respectively, and the abundance of 9 metabolites, such as argininosuccinic acid, was continuously decreased. After microwave radiation, the abundance of metabolites such as argininosuccinic acid was successively decreased, indicating that these metabolites could be potential biomarkers for hippocampal tissue injury.

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