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1.
Small ; : e2401831, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733226

RESUMO

Quasi-2D perovskites have attracted much attention in perovskite photovoltaics due to their excellent stability. However, their photoelectric conversion efficiency (PCE) still lags 3D counterparts, particularly with high short-circuit current (JSC) loss. The quantum confinement effect is pointed out to be the sole reason, which introduces widened bandgap and poor exciton dissociation, and undermines the light capture and charge transport. Here, the gradient incorporation of formamidinium (FA) cations into quasi-2D perovskite is proposed to address this issue. It is observed that FA prefers to incorporate into the larger n value phases near the film surface compared to the smaller n value phases in the bulk, resulting in a narrow bandgap and gradient structure within the film. Through charge dynamic analysis using in situ light-dark Kelvin probe force microscopy and transient absorption spectroscopy, it is demonstrated that incorporating 10% FA significantly facilitates efficient charge transfer between low n-value phases in the bulk and high n-value nearby film surface, leading to reduced charge accumulation. Ultimately, the device based on (AA)2(MA0.9FA0.1)4Pb5I16, where AA represents n-amylamine renowned for its exceptional environmental stability as a bulky organic ligand, achieves an impressive power conversion efficiency (PCE) of 18.58% and demonstrates enhanced illumination and thermal stability.

2.
Blood Sci ; 6(2): e00189, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38742239

RESUMO

An accurate prognostic model for acute myeloid leukemia (AML) can guide personalized treatment. In our prospective cohort of 591 patients newly diagnosed with AML, we evaluated the prognostic significance of serum albumin levels. We recognized baseline serum albumin as a prognostic factor by univariate Cox regression analysis (albumin-high vs albumin-low: overall survival [OS]: hazard ratio [HR]: 0.679, 95% confidence interval [CI]: 0.529-0.870, P = .002; cumulative incidence of relapse [CIR]: HR: 0.705, 95% CI: 0.530-0.938, P = .017) and multivariate Cox regression analysis (OS: HR per g/L: 0.966, 95% CI: 0.940-0.993, P = .014; CIR: HR per g/L: 0.959, 95% CI: 0.927-0.993, P = .017). In the subgroup analysis, serum albumin was prognostic significant in patients who received intermediate-dose cytarabine combined with daunorubicin and omacetaxine mepesuccinate induction (albumin-high vs albumin-low: OS: HR: 0.585, 95% CI: 0.397-0.863, P = .007; CIR: HR: 0.551, 95% CI: 0.353-0.861, P = .009) rather than those receiving conventional-dose induction regimens. In addition, the impact of baseline serum albumin level was evident in patients with intermediate European LeukemiaNet risk (albumin-high vs albumin-low: OS: HR: 0.617, 95% CI: 0.424-0.896, P = .011; CIR: HR: 0.617, 95% CI: 0.388-0.979, P = .040). Gene set enrichment analysis revealed that leukemia stem cell signatures were enriched in patients with low serum albumin levels. Our study suggested that baseline serum albumin level was associated with the inherent properties of AML and correlated with patient outcomes.

3.
Diabetes Metab Syndr Obes ; 17: 1987-1997, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38746045

RESUMO

Purpose: Diabetic nephropathy (DN), a major complication of diabetes mellitus, significantly impacts global health. Identifying individuals at risk of developing DN is crucial for early intervention and improving patient outcomes. This study aims to develop and validate a machine learning-based predictive model using integrated biomarkers. Methods: A cross-sectional analysis was conducted on a baseline dataset involving 2184 participants without DN, categorized based on their development of DN over a follow-up period of 36 months: DN (n=1270) and Non-DN (n=914). Various demographic and clinical parameters were analyzed. The findings were validated using an independent dataset comprising 468 participants, with 273 developing DN and 195 remaining as Non-DN over the follow-up period. Machine learning algorithms, alongside traditional descriptive statistics and logistic regression were used for statistical analyses. Results: Elevated levels of serum creatinine, urea, and reduced eGFR, alongside an increased prevalence of retinopathy and peripheral neuropathy, were prominently observed in those who developed DN. Validation on the independent dataset further confirmed the model's robustness and consistency. The SVM model demonstrated superior performance in the training set (AUC=0.79, F1-score=0.74) and testing set (AUC=0.83, F1-score=0.82), outperforming other models. Significant predictors of DN included serum creatinine, eGFR, presence of diabetic retinopathy, and peripheral neuropathy. Conclusion: Integrating machine learning algorithms with clinical and biomarker data at baseline offers a promising avenue for identifying individuals at risk of developing diabetic nephropathy in type 2 diabetes patients over a 36-month period.

4.
Adv Sci (Weinh) ; : e2402645, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738739

RESUMO

The photocatalytic reduction of CO2 represents an environmentally friendly and sustainable approach for generating valuable chemicals. In this study, a thiophene-modified highly conjugated asymmetric covalent triazine framework (As-CTF-S) is developed for this purpose. Significantly, single-component intramolecular energy transfer can enhance the photogenerated charge separation, leading to the efficient conversion of CO2 to CO during photocatalysis. As a result, without the need for additional photosensitizers or organic sacrificial agents, As-CTF-S demonstrates the highest photocatalytic ability of 353.2 µmol g-1 and achieves a selectivity of ≈99.95% within a 4 h period under visible light irradiation. This study provides molecular insights into the rational control of charge transfer pathways for high-efficiency CO2 photoreduction using single-component organic semiconductor catalysts.

5.
Chem Commun (Camb) ; 60(36): 4805-4809, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38602381

RESUMO

A rapid and eco-friendly route has been developed for the synthesis of SAPO-34 with short crystallization time (1-3 h), low silica content (as low as 6.2 wt%) and excellent methanol-to-olefin (MTO) catalytic performance by utilization of a recycled mother liquid at elevated crystallization temperature.

6.
Materials (Basel) ; 17(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612047

RESUMO

The phase segregation of wide-bandgap perovskite is detrimental to a device's performance. We find that Sodium Benzenesulfonate (SBS) can improve the interface passivation of PTAA, thus addressing the poor wettability issue of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA). This improvement helps mitigate interface defects caused by poor contact between the perovskite and PTAA, reducing non-radiative recombination. Additionally, enhanced interface contact improves the crystallinity of the perovskite, leading to higher-quality perovskite films. By synergistically controlling the crystallization and trap passivation to reduce the phase segregation, SBS-modified perovskite solar cells (PSCs) achieved a power conversion efficiency (PCE) of 20.27%, with an open-circuit voltage (Voc) of 1.18 V, short-circuit current density (Jsc) of 20.93 mA cm-2, and fill factor (FF) of 82.31%.

7.
Chin Med J (Engl) ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663857

RESUMO

BACKGROUND: Congenital heart disease (CHD) is a leading cause of birth defect-related mortality. However, more recent CHD mortality data for China are lacking. Additionally, limited studies have evaluated sex, rural-urban, and region-specific disparities of CHD mortality in China. METHODS: We designed a population-based study using data from the Dataset of National Mortality Surveillance in China between 2008 and 2021. We calculated age-adjusted CHD mortality using the sixth census data of China in 2010 as the standard population. We assessed the temporal trends in CHD mortality by age, sex, area, and region from 2008 to 2021 using the joinpoint regression model. RESULTS: From 2008 to 2021, 33,534 deaths were attributed to CHD. The period witnessed a two-fold decrease in the age-adjusted CHD mortality from 1.61 to 0.76 per 100,000 persons (average annual percent change [AAPC] = -5.90%). Females tended to have lower age-adjusted CHD mortality than males, but with a similar decline rate from 2008 to 2021 (females: AAPC = -6.15%; males: AAPC = -5.84%). Similar AAPC values were observed among people living in urban (AAPC = -6.64%) and rural (AAPC = -6.12%) areas. Eastern regions experienced a more pronounced decrease in the age-adjusted CHD mortality (AAPC = -7.86%) than central (AAPC = -5.83%) and western regions (AAPC = -3.71%) between 2008 and 2021. Approximately half of the deaths (46.19%) due to CHD occurred during infancy. The CHD mortality rates in 2021 were lower than those in 2008 for people aged 0-39 years, with the largest decrease observed among children aged 1-4 years (AAPC = -8.26%), followed by infants (AAPC = -7.01%). CONCLUSIONS: CHD mortality in China has dramatically decreased from 2008 to 2021. The slower decrease in CHD mortality in the central and western regions than in the eastern regions suggested that public health policymakers should pay more attention to health resources and health education for central and western regions.

8.
Mar Biotechnol (NY) ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668917

RESUMO

Polysaccharide-degrading bacteria are key participants in the global carbon cycle and algal biomass recycling. Herein, a polysaccharide lyase-producing strain HB226069 was isolated from Sargassum sp. from Qingge Port, Hainan, China. Results of the phylogenetic of the 16S rRNA gene and genotypic analysis indicated that the isolate should be classified as Microbulbifer thermotolerans. The whole genome is a 4,021,337 bp circular chromosome with a G+C content of 56.5%. Analysis of the predicted genes indicated that strain HB226069 encoded 161 carbohydrate-active enzymes (CAZymes), and abundant putative enzymes involved in polysaccharide degradation were predicted, including alginate lyase, fucosidase, agarase, xylanase, cellulase, pectate lyase, amylase, and chitinase. Three of the putative polysaccharide lyases from PL7 and PL17 families were involved in alginate degradation. The alginate lyases of strain HB226069 showed the maximum activity of 117.4 U/mL at 50 °C, pH 7.0, and 0.05 M FeCl3, while exhibiting the best stability at 30 °C and pH 7.0. The Thin Layer Chromatography (TLC) and Electrospray Ionization Mass Spectrometry (ESI-MS) analyses indicated that the alginate oligosaccharides (AOSs) degraded by the partially purified alginate lyases contained oligosaccharides of DP2-DP5 and monosaccharide while reacting for 36 h. The complete genome of M. thermotolerans HB226069 enriches our understanding of the mechanism of polysaccharide lyase production and supports its potential application in polysaccharide degradation.

9.
Sci Rep ; 14(1): 8774, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627468

RESUMO

Optical field imaging technology does not require a complicated optical path layout and thus reduces hardware costs. Given that only one single exposure of a single camera can obtain three-dimensional information, this paper proposes an improved calibration method for depth measurement based on the theoretical model of optical field imaging. Specifically, the calibration time can be reduced since the Gaussian fitting can reduce the number of refocused images used to obtain the optimal refocusing coefficient calibration. Moreover, the proposed method achieves the same effect as the multiple refocusing calibration strategy but requires less image processing time during calibration. At the same time, this method's depth resolution is analyzed in detail.

10.
Cancer Med ; 13(5): e7015, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38491808

RESUMO

BACKGROUND: Gastric cardia adenocarcinoma (GCA) is classified as Siewert type II adenocarcinoma at the esophagogastric junction in Western countries. The majority of GCA patients do not exhibit early warning symptoms, leading to over 90% of diagnoses at an advanced stage, resulting in a grim prognosis, with less than a 20% 5-year survival rate. METHOD: Metabolic features of 276 GCA and 588 healthy controls were characterized through a widely-targeted metabolomics by UPLC-MS/MS analysis. This study encompasses a joint pathway analysis utilizing identified metabolites, survival analysis in both early and advanced stages, as well as high and negative and low expression of HER2 immunohistochemistry staining. Machine learning techniques and Cox regression models were employed to construct a diagnostic panel. RESULTS: A total of 25 differential metabolites were consistently identified in both discovery and validation sets based on criteria of p < 0.05, (VIP) ≥ 1, and FC ≥ 2 or FC ≤ 0.5. Early-stage GCA patients exhibited a more favorable prognosis compared to those in advanced stages. HER2 overexpression was associated with a more positive outcome compared to the negative and low expression groups. Metabolite panel demonstrated a robust diagnostic performance with AUC of 0.869 in discovery set and 0.900 in validation set. CONCLUSIONS: A total of 25 common and stable differential metabolites may hold promise as liquid non-invasive indicators for GCA diagnosis. HER2 may function as a tumor suppressor gene in GCA, as its overexpression is associated with improved survival. The downregulation of bile acid metabolism in GCA may offer valuable theoretical insights and innovative approaches for precision-targeted treatments in GCA patients.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Humanos , Cárdia/patologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Neoplasias Gástricas/patologia , Adenocarcinoma/patologia , Biomarcadores
11.
Microorganisms ; 12(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38543490

RESUMO

Bacillus subtilis, a probiotic bacterium with engineering potential, is widely used for the expression of exogenous proteins. In this study, we utilized the integrative plasmid pDG364 to integrate the hemagglutinin-neuraminidase (HN) gene from Newcastle disease virus (NDV) into the genome of the B. subtilis 168 model strain. We successfully constructed a recombinant B. subtilis strain (designated B. subtilis RH) that displays a truncated HN antigen fragment on the surface of its spores and further evaluated its immunogenic effects in mice. Using ELISA, we quantified the levels of IgG in serum and secretory IgA (sIgA) in intestinal contents. The results revealed that the recombinant B. subtilis RH elicited robust specific mucosal and humoral immune responses in mice. Furthermore, B. subtilis RH demonstrated potential mucosal immune adjuvant properties by fostering the development of immune organs and augmenting the number of lymphocytes in the small intestinal villi. Additionally, the strain significantly upregulated the relative expression of inflammatory cytokines such as IL-1ß, IL-6, IL-10, TNF-α, and IFN-γ in the small intestinal mucosa. In conclusion, the B. subtilis RH strain developed in this study exhibits promising mucosal immunogenic effects. It holds potential as a candidate for an anti-NDV mucosal subunit vaccine and offers a novel preventive strategy for the poultry industry against this disease.

12.
Antonie Van Leeuwenhoek ; 117(1): 46, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427093

RESUMO

The fast-growing rhizobia-like strains S101T and S153, isolated from root nodules of soybean (Glycine max) in Sichuan, People's Republic of China, underwent characterization using a polyphasic taxonomy approach. The strains exhibited growth at 20-40 °C (optimum, 28 °C), pH 4.0-10.0 (optimum, pH 7.0) and up to 2.0% (w/v) NaCl (optimum, 0.01%) on Yeast Mannitol Agar plates. The 16S rRNA gene of strain S101T showed 98.4% sequence similarity to the closest type strain, Ciceribacter daejeonense L61T. Major cellular fatty acids in strain S101T included summed feature 8 (C18:1ω7c and/or C18:1ω6c) and C19:0 cyclo ω8c. The predominant quinone was ubiquinone-10. The polar lipids of strain S101T included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethyl ethanolamine, phosphatidyl ethanolamine, amino phospholipid, unidentified phosphoglycolipid and unidentified amino-containing lipids. The DNA G + C contents of S101T and S153 were 61.1 and 61.3 mol%, respectively. Digital DNA-DNA hybridization relatedness and average nucleotide identity values between S101T and C. daejeonense L61T were 46.2% and 91.4-92.2%, respectively. In addition, strain S101T promoted the growth of soybean and carried nitrogen fixation genes in its genome, hinting at potential applications in sustainable agriculture. We propose that strains S101T and S153 represent a novel species, named Ciceribacter sichuanensis sp. nov., with strain S101T as the type strain (= CGMCC 1.61309 T = JCM 35649 T).


Assuntos
Glycine max , Fosfolipídeos , Humanos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Filogenia , DNA Bacteriano/genética , Fosfolipídeos/química , Ácidos Graxos/química , Etanolaminas , China , Técnicas de Tipagem Bacteriana
13.
Food Microbiol ; 120: 104465, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431317

RESUMO

Biological antagonists serve as the most important green alternatives to chemical fungicides, a class of microorganism that inhibits the growth of pathogenic fungi to reduce fruit incidence. In this paper, healthy and diseased peach fruit was selected for amplicon sequencing of the epiphytic microbiota on their surface to obtain a comprehensive understanding. Community structure, diversity and LefSe analysis were performed to screen Acetobacter, Muribaculaceae and Burkholderia as the core bacteria, Mycosphaerella, Penicillium and Alternaria as the core fungi, they showed significant differences and were highly enriched. Two strains fungi (Penicillium K3 and N1) and one strain antagonistic bacteria (Burkholderia J2) were isolated. The in intro test results indicated the bacterial suspension, fermentation broth and volatile organic compounds of antagonistic bacteria J2 were able to significantly inhibit pathogen growth. In vivo experiments, peach was stored at 28 °C for 6 days after different treatments, and samples were taken every day. It was found that Burkholderia J2 enhanced peach resistance by increasing the activities of antioxidant-related enzymes such as SOD, POD, PAL, PPO, GR, MDHAR, and DHAR. The results improved that Burkholderia J2 has great biocontrol potential and could be used as a candidate strain for green control of blue mold.


Assuntos
Penicillium , Prunus persica , Prunus persica/microbiologia , Bactérias/genética , Frutas/microbiologia , Alternaria
14.
Med Eng Phys ; 123: 104085, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38365338

RESUMO

Extreme bradycardia, extreme tachycardia, ventricular flutter fib, and ventricular tachycardia are four malignant arrhythmias (MAs) that lead to sudden cardiac death. It is very important to detect them in daily life. The arterial blood pressure (ABP) signal contains abundant pathological information about four MAs and is easy to be recorded under domestic conditions. Thus, a synthesis-by-analysis (SA) modeling method for ABP signal was proposed to detect the four MAs in this study. The average models of MAs and healthy subjects were obtained by SA modeling, and the change of each ABP wave was quantitively described by twelve parameters of wave models. Then, the probabilistic neural network (PNN) and random forest (RF) are trained to detect the MAs. The experimental data were employed from Fantasia and the 2015 PhysioNet/CinC Challenge databases. The SA modeling results show that some pathological and physiological changes could be extracted from the average models. The two-sample ks-test results between different groups are markedly different (h = 1, p < 0.05). The detection results show that the performances of PPN classifiers are less than that of RF. The kappa coefficients (KC) for the RF classifiers are 97.167 ± 1.46 %, 97.888 ± 0.808 %, 99.895 ± 0.545 %, 98.575 ± 1.683 % and 92.241 ± 1.517 %, respectively. The mean KC is 97.083 ± 0.67 %. Compared to the performance of some existing studies, the proposed method has better performance and is potential to diagnose MAs in m-health.


Assuntos
Pressão Arterial , Eletrocardiografia , Humanos , Arritmias Cardíacas/diagnóstico , Redes Neurais de Computação , Pressão Sanguínea
15.
Eur J Radiol Open ; 12: 100550, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38314183

RESUMO

Objectives: To determine whether contrast-enhanced CT radiomics features can preoperatively predict lymphovascular invasion (LVI) and perineural invasion (PNI) in gastric cancer (GC). Methods: A total of 148 patients were included in the LVI group, and 143 patients were included in the PNI group. Three predictive models were constructed, including clinical, radiomics, and combined models. A nomogram was developed with clinical risk factors to predict LVI and PNI status. The predictive performance of the three models was mainly evaluated using the mean area under the curve (AUC). The performance of three predictive models was assessed concerning calibration and clinical usefulness. Results: In the LVI group, the predictive power of the combined model (AUC=0.871, 0.822) outperformed the clinical model (AUC=0.792, 0.728) and the radiomics model (AUC=0.792, 0.728) in both the training and testing cohorts. In the PNI group, the combined model (AUC=0.834, 0.828) also had better predictive power than the clinical model (AUC=0.764, 0.632) and the radiomics model (AUC=0.764, 0.632) in both the training and testing cohorts. The combined models also showed good calibration and clinical usefulness for LVI and PNI prediction. Conclusion: CECT-based radiomics analysis might serve as a non-invasive method to predict LVI and PNI status in GC.

16.
J Agric Food Chem ; 72(7): 3800-3813, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38327020

RESUMO

Folate was enriched during quinoa germination, while molecular mechanisms were not well understood. In this study, three quinoa varieties were selected for germination, and changes in substrate content and enzyme activity of the folate biosynthesis pathway were monitored. 5-Methyltetrahydrofolate (5-CH3-THF) and 5-formyltetrahydrofolate (5-CHO-THF) were significantly enriched in quinoa sprouts. Among the selected varieties, QL-2 exhibited the lowest content of the oxidation product MeFox and the highest total folate content. Based on transcriptome analysis, the p-ABA branch was found to be crucial for folate accumulation, while the pterin branch served as a key control point for the one carbon pool by folate pathway, which limited further folate biosynthesis. In the one carbon pool by folate pathway, genes CqMTHFR and CqAMT significantly contributed to the enrichment of 5-CH3-THF and 5-CHO-THF. Findings gained here would facilitate the potential application of quinoa sprouts as an alternative strategy for folate supplementation.


Assuntos
Chenopodium quinoa , Chenopodium quinoa/genética , Chenopodium quinoa/química , Ácido Fólico , Sementes/genética , Sementes/química , Perfilação da Expressão Gênica , Carbono/análise
17.
Plant J ; 118(2): 549-564, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38184780

RESUMO

Epigenetic regulation of gene expression plays a crucial role in plant development and environmental adaptation. The H3K4me3 and H3K27me3 have not only been discovered in the regulation of gene expression in multiple biological processes but also in responses to abiotic stresses in plants. However, evidence for the presence of both H3K4me3 and H3K27me3 on the same nucleosome is sporadic. Cold-induced deposition of bivalent H3K4me3-H3K27me3 modifications and nucleosome depletion over a considerable number of active genes is documented in potato tubers and provides clues on an additional role of the bivalent modifications. Limited by the available information of genes encoding PcG/TrxG proteins as well as their corresponding mutants in potatoes, the molecular mechanism underlying the cold-induced deposition of the bivalent mark remains elusive. In this study, we found a similar deposition of the bivalent H3K4me3-H3K27me3 mark over 2129 active genes in cold-treated Arabidopsis Col-0 seedlings. The expression levels of the bivalent mark-associated genes tend to be independent of bivalent modification levels. However, these genes were associated with greater chromatin accessibility, presumably to provide a distinct chromatin environment for gene expression. In mutants clf28 and lhp1, failure to deposit H3K27me3 in active genes upon cold treatment implies that the CLF is potentially involved in cold-induced deposition of H3K27me3, with assistance from LHP1. Failure to deposit H3K4me3 during cold treatment in atx1-2 suggests a regulatory role of ATX1 in the deposition of H3K4me3. In addition, we observed a cold-induced global reduction in nucleosome occupancy, which is potentially mediated by LHP1 in an H3K27me3-dependent manner.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Histonas/genética , Histonas/metabolismo , Nucleossomos/genética , Nucleossomos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Epigênese Genética , Proteínas de Arabidopsis/metabolismo , Cromatina/genética , Cromatina/metabolismo , Regulação da Expressão Gênica de Plantas/genética
19.
Food Funct ; 15(3): 1340-1354, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38205623

RESUMO

The cholesterol-lowering effect of lactic acid bacteria with high activity of bile salt hydrolase (BSH) is unclear. We believe that distinguishing BSH substrate specificity is necessary to study the effect of various BSH enzymes. We engineered a BSH mutant enzyme recombinant strain named F67A, which exclusively hydrolyzes taurocholic acid (TCA) using site-directed mutagenesis, and a previously lab-constructed BSH recombinant strain, YB81 that exclusively hydrolyzes glycocholic acid (GCA). We also constructed the recombinant strain named NB5462, which carries the empty pSIP411 plasmid and was used as a blank control strain. The intestinal flora in pseudo-germ-free (PGF) mice in which intestinal flora were eliminated via antibiotics, and F67A successfully reduced serum cholesterol levels in high-cholesterol diet-fed mice, whereas YB81 did not yield the same results. However, YB81 regained its cholesterol-lowering capacity in specific pathogen-free (SPF) mice with intact intestinal flora. The cholesterol-lowering mechanism of F67A involved modifying the bile acid pool through BSH enzyme activity. This adjustment regulated the expression of intestinal farnesoid X receptor and subsequently elevated hepatic cholesterol 7α-hydroxylase (CYP7A1), effectively reducing cholesterol levels. Conversely, GCA, the substrate of YB81, was found in minimal quantities in mice, preventing it from inducing changes in bile acid pools. In the presence of intestinal flora, the YB81 BSH enzyme induced notable alterations in bile acids by regulating changes in the intestinal flora and BSH within the flora, ultimately resulting in cholesterol reduction. This is the first study investigating the substrate specificity of BSH, demonstrating that different substrate-specific BSH enzymes exhibit cholesterol-lowering properties. Additionally, we elaborate on the mechanism of BSH-mediated enterohepatic axis regulation.


Assuntos
Amidoidrolases , Lactobacillus , Animais , Camundongos , Lactobacillus/metabolismo , Especificidade por Substrato , Amidoidrolases/metabolismo , Colesterol , Dieta , Ácidos e Sais Biliares
20.
Cell Death Discov ; 10(1): 20, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212314

RESUMO

The excessive activation of the Wnt/ß-catenin signaling pathway is an important regulatory mechanism that underlies the excessive proliferation and impaired differentiation of type 2 alveolar epithelial cells (AEC-II) in bronchopulmonary dysplasia (BPD). Sox9 has been shown to be an important repressor of the Wnt/ß-catenin signaling pathway and plays an important regulatory role in various pathophysiological processes. We found that the increased expression of Sox9 in the early stages of BPD could downregulate the expression of ß-catenin and promote the differentiation of AEC-II cells into AEC-I, thereby alleviating the pathological changes in BPD. The expression of Sox9 in BPD is regulated by long noncoding RNA growth arrest-specific 5. These findings may provide new targets for the early intervention of BPD.

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