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1.
Anim Biosci ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38665071

RESUMO

Objective: The objective of this study was to investigate the effects of prolactin (PRL) on the proliferation and apoptosis of ovine ovarian granulosa cells (GCs) and the secretion of estrogen (E2) and progesterone (P4), as well as to explore the effects of PRL on related genes and proteins. Methods: We isolated ovarian GCs from 1-year-old small-tail Han sheep and identified PRL receptor (PRLR) on ovaries and follicle stimulating hormone receptor (FSHR) on ovarian GCs, respectively, using immunohistochemistry. PRL (0, 0.05, 0.50, 5.00 µg/mL) were added to GCs in vitro along with FSH, cell proliferation was measured by Cell Counting Kit-8 (CCK-8) and apoptosis by flow cytometry. The measurement of E2 and P4 content by ELISA after 24h and 48h. The expression of functional genes and proteins was identified by RT-qPCR and Western-blot after 24h. Results: PRLR was expressed in both follicular GCs and corpus luteum, whereas FSHR was expressed specifically. The proliferative activity was lower on day 1 while higher on day 4 and day 5. The apoptosis rate of GCs in the 0.05 µg/mL group was significantly higher than that in the control group after treatment with PRL for 24 h (p<0.05). Compared with the control group, the secretion of E2 in GCs was reduced significantly (p<0.05) in PRL treatment for 24h and 48h, while the secretion of P4 was significantly increased (p<0.05). The mRNA expression levels of PRLR, FSHR, LHR, CYP11A1, HSD3B7 and STAR were significantly higher than those in the control group (p<0.01), and the relative abundance of BCL2 in all PRL group were increased after PRL treatment. Conclusion: PRL promoted the proliferation of GCs and supraphysiological concentrations inhibited apoptosis caused by down-regulation of BAX and up-regulation of BCL2. PRL inhibited E2 by down-regulating CYP19A1 and promoted P4 by up-regulating CYP11A1, STAR and HSD3B7.

2.
Anal Chem ; 96(15): 5741-5745, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38573003

RESUMO

Fucosylation is an important structural feature of glycans and plays an essential role in the regulation of glycoprotein functions. Fucosylation can be classified into core- (CF) and antenna-fucosylation (AF, also known as (sialyl-) Lewis) based on the location on N-glycans, and they perform distinct biological functions. In this study, core- and antenna-fucosylated N-glycans on human serum glycoproteins that hold great clinical application values were systematically characterized at the site-specific level using StrucGP combined with the recently developed fucosylation assignment method. The results showed that fucosylation was widely distributed on serum glycoproteins, with 50% of fucosylated glycopeptides modified by AF N-glycans, 37% by CF N-glycans, and 13% by dual-fucosylated N-glycans. Interestingly, CF and AF N-glycans preferred to modify different groups of serum glycoproteins with different tissue origins and were involved in distinctive biological processes. Specifically, AF N-glycoproteins are mainly from the liver and participated in complement activation, blood coagulation, and endopeptidase activities, while CF N-glycoproteins originate from diverse tissues and are mainly involved in cell adhesion and signaling transduction. These data further enhanced our understanding of fucosylation on circulation glycoproteins.


Assuntos
Glicoproteínas , Fígado , Humanos , Glicoproteínas/química , Glicosilação , Fígado/metabolismo , Polissacarídeos/química , Fucose/química
3.
Chem Asian J ; : e202400101, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629889

RESUMO

Two uranium oxide hydrate frameworks (UOHFs) with either Dy3+ or Lu3+ ions, Dy1.36(H2O)6[(UO2)10UO13(OH)4] (UOHF-Dy) or Lu2(H2O)8[(UO2)10UO14(OH)3] (UOHF-Lu), were synthesized hydrothermally and characterized with a range of structural and spectroscopic techniques. Although SEM-EDS analysis confirmed the same atomic ratio of ~5.5 for U:Dy and U:Lu, they displayed different crystal morphologies, needles for UOHF-Dy in the orthorhombic C2221 space group and plates for UOHF-Lu in the triclinic P-1 space group. Both frameworks are composed of ß-U3O8 type layers linked by pentagonal bipyramidal uranium polyhedra, with the Dy3+/Lu3+ ions inside the channels. However, the arrangements of Dy3+/Lu3+ ions are different, with disordered Dy3+ ions well aligned at the centers of the channels and single Lu3+ ions well-separated in a zigzag pattern in the channels. While the characteristic vibrational modes were revealed by Raman spectroscopy, the presence of a pentavalent uranium center in UOHF-Lu was confirmed with diffuse reflectance spectroscopy. The formation of two types of UOHFs with lanthanide ions, high or low symmetry, and the structure trend were discussed regards to synthesis conditions and lanthanide ionic radius. This work highlights the complex chemistry driving the formation of UOHFs with lanthanide ions and has implications to the spent nuclear fuel under geological disposal.

4.
Food Chem ; 449: 139198, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38574526

RESUMO

The preparation of high specificity and affinity antibodies is challenging due to limited information on characteristic groups of haptens in traditional design strategy. In this study, we first predicted characteristic groups of flurogestone acetate (FGA) using quantitative analysis of molecular surface combined with atomic charge distribution. Subsequently, FGA haptens were rationally designed to expose these identified characteristic groups fully. As a result, seven monoclonal antibodies were obtained with satisfactory performance, exhibiting IC50 values from 0.17 to 0.45 µg/L and negligible cross-reactivities below 1% to other 18 hormones. The antibody recognition mechanism further confirmed hydrogen bonds and hydrophobic interactions involving predicted FGA characteristic groups and specific amino acids in the antibodies contributed to their high specificity and affinity. Finally, one selective and sensitive ic-ELISA was developed for FGA determination with a detection limit as low as 0.12 µg/L, providing an efficient tool for timely monitoring of FGA in goat milk samples.

5.
World J Gastrointest Oncol ; 16(3): 670-686, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577437

RESUMO

BACKGROUND: The incidence and mortality of colorectal cancer (CRC) are among the highest in the world, and its occurrence and development are closely related to tumor neovascularization. When the balance between pigment epithelium-derived factors (PEDF) that inhibit angiogenesis and vascular endothelial growth factors (VEGF) that stimulate angiogenesis is broken, angiogenesis is out of control, resulting in tumor development. Therefore, it is very necessary to find more therapeutic targets for CRC for early intervention and later treatment. AIM: To investigate the expression and significance of PEDF, VEGF, and CD31-stained microvessel density values (CD31-MVD) in normal colorectal mucosa, adenoma, and CRC. METHODS: In this case-control study, we collected archived wax blocks of specimens from the Digestive Endoscopy Center and the General Surgery Department of Chengdu Second People's Hospital from April 2022 to October 2022. Fifty cases of specimen wax blocks were selected as normal intestinal mucosa confirmed by electronic colonoscopy and concurrent biopsy (normal control group), 50 cases of specimen wax blocks were selected as colorectal adenoma confirmed by electronic colonoscopy and pathological biopsy (adenoma group), and 50 cases of specimen wax blocks were selected as CRC confirmed by postoperative pathological biopsy after inpatient operation of general surgery (CRC group). An immunohistochemical staining experiment was carried out to detect PEDF and VEGF expression in three groups of specimens, analyze their differences, study the relationship between the two and clinicopathological factors in CRC group, record CD31-MVD in the three groups, and analyze the correlation of PEDF, VEGF, and CD31-MVD in the colorectal adenoma group and the CRC group. The F test or adjusted F test is used to analyze measurement data statistically. Kruskal-Wallis rank sum test was used between groups for ranked data. The chi-square test, adjusted chi-square test, or Fisher's exact test were used to compare the rates between groups. All differences between groups were compared using the Bonferroni method for multiple comparisons. Spearman correlation analysis was used to test the correlation of the data. The test level (α) was 0.05, and a two-sided P< 0.05 was considered statistically significant. RESULTS: The positive expression rate and expression intensity of PEDF were gradually decreased in the normal control group, adenoma group, and CRC group (100% vs 78% vs 50%, χ2 = 34.430, P < 0.001; ++~++ vs +~++ vs -~+, H = 94.059, P < 0.001), while VEGF increased gradually (0% vs 68% vs 96%, χ2 = 98.35, P < 0.001; - vs -~+ vs ++~+++, H = 107.734, P < 0.001). In the CRC group, the positive expression rate of PEDF decreased with the increase of differentiation degree, invasion depth, lymph node metastasis, distant metastasis, and TNM stage (χ2 = 20.513, 4.160, 5.128, 6.349, 5.128, P < 0.05); the high expression rate of VEGF was the opposite (χ2 = 10.317, 13.134, 17.643, 21.844, 17.643, P < 0.05). In the colorectal adenoma group, the expression intensity of PEDF correlated negatively with CD31-MVD (r = -0.601, P < 0.001), whereas VEGF was not significantly different (r = 0.258, P = 0.07). In the CRC group, the expression intensity of PEDF correlated negatively with the expression intensity of CD31-MVD and VEGF (r = -0.297, P < 0.05; r = -0.548, P < 0.05), while VEGF expression intensity was positively related to CD31-MVD (r = 0.421, P = 0.002). CONCLUSION: It is possible that PEDF can be used as a new treatment and prevention target for CRC by upregulating the expression of PEDF while inhibiting the expression of VEGF.

6.
World J Gastrointest Oncol ; 16(3): 750-760, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577441

RESUMO

BACKGROUND: Lipid metabolism reprogramming is suspected to exist in pre-cancerous lesions, including colorectal adenoma. Screening colonoscopy frequently reveals chicken skin mucosa (CSM; white or yellow-white speckled mucosa) surrounding colorectal polyps, caused by macrophages engulfing and accumulating the lipids decomposed by colon cells or adjacent tumors. CSM-positive colorectal polyps are associated with various diseases; however, their prognosis varies greatly. Cold snare polypectomy is commonly used to resect lesions up to 10 to 15 mm in diameter without signs of submucosal invasion but is controversial for CSM-positive colorectal polyps. Improved imaging is required to diagnose and treat CSM-positive colorectal polyps. AIM: To highlight the clinical significance of CSM surrounding colorectal polyps and clarify the associated treatment for endoscopists. METHODS: This retrospective cohort study included 177 patients with CSM-positive colorectal polyps diagnosed using endoscopy. All patient-related information was extracted from the Goldisc soft-clinic DICOM system or electronic medical record system. Based on the pathological results, patients were classified as non-neoplastic polyps (five juvenile polyps), neoplastic polyps, non-invasive high-grade neoplasia (NHGN), or submucosal invasive carcinoma (SM stage cancer). We analyzed and compared the clinical features, suspected risk factors for malignant transformation of neoplastic polyps, and early infiltration of submucosal carcinoma. RESULTS: The diameters of NHGN and SM polyps were much smaller than those of neoplastic polyps. Most NHGN polyps had a deeper red mucosal color. On logistic regression analyses, diameter and deeper red mucosal color were independent risk factors for malignant transformation of neoplastic polyps. Type 1 CSM was more common in high-grade intraepithelial neoplasia and SM; type 2 CSM was more common in neoplastic polyps. Logistic regression analyses revealed no significant differences in the malignant transformation of neoplastic polyps or early submucosal invasion of CSM-positive colorectal cancer. Changes in the CSM mucosa surrounding neoplastic polyps and submucosal invasion of colorectal cancer disappeared within 12 months. No tumor recurrence was found during either partial or complete endoscopic resection of the CSM. CONCLUSION: CSM-positive colorectal polyps > 1 cm in diameter or with deeper red mucosa may be related to NHGN. Resection of CSM surrounding colorectal adenomas did not affect tumor recurrence.

7.
Phys Chem Chem Phys ; 26(16): 12717-12724, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38606481

RESUMO

Pivotal enhancements in electronic minimization algorithms, which are vital for the advancement of computational materials science, are introduced in this research. Our research is dedicated to refining the DIIS algorithm specifically for electronic structure calculations of silicon (Si) and gallium arsenide (GaAs) solar cells, aiming to enhance their efficiency and stability. We have enriched DIIS by integrating a weight regularization factor, significantly bolstering its convergence stability. This modification enhances iteration robustness and curtails the average iteration duration, thus streamlining the convergence process. Furthermore, we have incorporated the conjugate gradient (CG) algorithm to proficiently resolve symmetric positive definite residual matrices. This inclusion substantially accelerates the solution-finding process within the DIIS framework. A novel aspect of our research is the application of reverse automatic differentiation (AD), deployed in two distinct methodologies: the construction of the Jacobian matrix and direct chain rule application for gradient computation. These approaches involve sophisticated mathematical techniques that enhance computational precision and efficiency specifically for Si and GaAs solar cell materials in determining the optimal weights for residual combinations during DIIS iterations. The integration of these advanced methods into the DIIS algorithm not only augments its convergence stability but also ensures a substantial reduction in total computational time. Our findings demonstrate that the enhanced DIIS, CG-enhanced DIIS, and AD-integrated DIIS methods collectively lead to a more efficient electronic minimization process. This balance of stability and efficiency is crucial in high-performance computational materials science, particularly for complex systems analysis. The findings of this research represent a notable advancement in computational strategies for Si and GaAs solar cell materials, providing enhanced methodologies and insights that significantly improve the efficiency and stability of electronic structure calculations in these critical components of renewable energy technologies.

8.
Sci Rep ; 14(1): 8743, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627506

RESUMO

The IVa subfamily of glycine-rich proteins (GRPs) comprises a group of glycine-rich RNA binding proteins referred to as GR-RBPa here. Previous studies have demonstrated functions of GR-RBPa proteins in regulating stress response in plants. However, the mechanisms responsible for the differential regulatory functions of GR-RBPa proteins in different plant species have not been fully elucidated. In this study, we identified and comprehensively studied a total of 34 GR-RBPa proteins from five plant species. Our analysis revealed that GR-RBPa proteins were further classified into two branches, with proteins in branch I being relatively more conserved than those in branch II. When subjected to identical stresses, these genes exhibited intensive and differential expression regulation in different plant species, corresponding to the enrichment of cis-acting regulatory elements involving in environmental and internal signaling in these genes. Unexpectedly, all GR-RBPa genes in branch I underwent intensive alternative splicing (AS) regulation, while almost all genes in branch II were only constitutively spliced, despite having more introns. This study highlights the complex and divergent regulations of a group of conserved RNA binding proteins in different plants when exposed to identical stress conditions. These species-specific regulations may have implications for stress responses and adaptations in different plant species.


Assuntos
Plantas , Sequências Reguladoras de Ácido Nucleico , Plantas/genética , Plantas/metabolismo , Estresse Fisiológico/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Glicina/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia
9.
Nanoscale ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602047

RESUMO

The sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) significantly impede the broader implementation of Zn-air batteries (ZABs), underscoring the necessity for advanced high-efficiency materials to catalyze these electrochemical processes. Recent advancements have highlighted the potential of transition metal/carbon nanofiber (TM/CNF) composite materials, synthesized via electrospinning technology, due to their expansive surface area, profusion of active sites, and elevated catalytic efficacy. This review comprehensively examines the structural characteristics of TM/CNFs, with a particular emphasis on the pivotal role of electrospinning technology in fabricating diverse structural configurations. Additionally, it delves into the mechanistic underpinnings of various strategies aimed at augmenting the catalytic activity of TM/CNFs. A meticulous discourse is also presented on the application scope of TM/CNFs in the realm of electrocatalysis, with a special focus on their impact on the performance of assembled ZABs. Lastly, this review encapsulates the challenges and future prospects in the development of TM/CNF composite materials via electrospinning, aiming to provide an exhaustive understanding of the current state of research in this domain and to foster further advancements in the commercialization of ZABs.

10.
Foods ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38472820

RESUMO

In this study, we established a new methodology for preparing 5'-nucleotidase (5'-NT) with the aim of enhancing our understanding of its enzyme activity and laying a basis for regulating the content of umami-enhancing nucleotides in pork. 5'-NT was prepared with Sephadex gel filtration and reverse-phase high-performance liquid chromatography, and its enzymatic properties and catalytic activity were evaluated. The results show that the molecular weight of the prepared 5'-NT was 57 kDa, the optimal catalytic temperature was 40 °C, and the optimal pH was 8. Zn2+, and sucrose showed inhibitory effects on the activity of 5'-NT, while K+, Na+, Ca2+, Mg2+, glucose, fructose, and trehalose promoted the activity of the studied compound. The prepared 5'-NT exhibited higher catalytic activity and selectivity against IMP compared with its commercial counterpart, while its catalytic activity against XMP was not significant (p > 0.05). In brief, we established a new methodology for preparing 5'-NT, enhancing our understanding of its enzyme activity and providing a solid basis for regulating the content of umami-enhancing nucleotides in pork through the control of endogenous 5'-NT activity.

11.
Materials (Basel) ; 17(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473609

RESUMO

In recent years, significant attention has been paid to the use of calcium sulfate whiskers (CSWs) to enhance the performance of cement-based materials (CBM). This technology has attracted widespread interest from researchers because it enhances the performance and sustainability of CBM by modifying the crystal structure of calcium sulfate. This article summarizes the fundamental properties and preparation methods of calcium sulfate whisker materials as well as their applications in cement, potential advantages and disadvantages, and practical applications and prospects. The introduction of CSWs has been demonstrated to enhance the strength, durability, and crack resistance of CBM while also addressing concerns related to permeability and shrinkage. The application of this technology is expected to improve the quality and lifespan of buildings, reduce maintenance costs, and positively impact the environment. The use of CSWs in CBM represents a promising material innovation that offers lasting and sustainable advancement in the construction industry.

12.
Animals (Basel) ; 14(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38539922

RESUMO

Transport stress can cause damage to animals. In this experiment, 60 four-month-old lambs were randomly divided into three groups: CG (basal diet), EG (basal diet + 375 mg/d/lamb electrolytic multivitamin), and NG (basal diet + 200 mg/d/lamb neomycin). The results were as follows: during road transport, in all groups, the levels of SOD, T-AOC, and GSP-Px, and mRNA expressions of CAT, SOD, Nrf2, HO-1, and Bcl-2 in the jejunum and colon decreased (p < 0.01). However, mRNA expressions of Keap1, IL-1ß, IL-2, IL-12, Bax, and Caspase3 in the jejunum and colon and the level of MDA increased (p < 0.01). The concentrations of IgA, IgG, and sIgA in the jejunum and colon also decreased (p < 0.01). In the EG and NG, the levels of SOD (p < 0.05) and T-AOC (p < 0.01) increased, and the level of MDA decreased (p < 0.01). However, in the jejunum, the levels of SOD and T-AOC, the concentrations of IgA and IgG, and mRNA expression of Bcl-2 increased (p < 0.05). mRNA expressions of IL-1, IL-2, and Caspase 3 (p < 0.05), and mRNA expression of IL-12 (p < 0.01) decreased. In the colon, SOD activity and the concentration of sIgA increased (p < 0.01). The level of MDA and mRNA expressions of IL-2 and Caspase 3 also decreased (p < 0.05). In the jejunum and colon, mRNA expression of SOD (p < 0.05) and mRNA expression of Nrf2 increased (p < 0.01). mRNA expression of Keap1 (p < 0.05) and Bax (p < 0.01) decreased. In summary, road transport can cause a decrease in antioxidant activity and immunity of lambs and an increase in oxidative damage. Electrolytic multivitamins and neomycin can improve immune function and potentially reduce oxidative damage to the jejunum and colon.

13.
Sci Total Environ ; 926: 171989, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547971

RESUMO

To understand the characteristics of atmospheric pollution above the urban canopy in warm seasons, the characteristics of sub-micron aerosol (PM1) was studied based on high-altitude observations at the Beijing 325 m meteorological tower. The PM1 at 260 m was 34, 29 and 21 µg m-3 in May 2015, June 2015, and June 2017, respectively, indicating a reduction in PM1 pollution above the urban canopy. Meanwhile, an overall decrease was also observed in the concentrations of all PM1 chemical species (excluding Chl and BC) and organic aerosol (OA) factors. Previous instances of heavy haze in Beijing often coincided with high humidity and stagnant weather conditions. However, the heightened pollution episodes in June 2017 were accompanied by high wind speeds and low relative humidity. Compared to May 2015, the contribution of secondary components to PM1 in June 2017 was more prominent, with the total proportion of SNA (sulfate, nitrate, and ammonium) and more-oxidized oxygenated OA (MO-OOA) to PM1 increased by approximately 10 %. Secondary species of NH4NO3, (NH4)2SO4, and MO-OOA, as well as black carbon, collectively contributed the vast majority of aerosol extinction coefficient (bext), with the four species contributing a total of ≥96 % to bext at 260 m. Hydrocarbon-like OA, cooking OA, and less-oxidized oxygenated OA have undergone significant reductions, so continued emphasis on controlling local sources to reduce these three aerosol species and addressing regional sources to further mitigate overall aerosol species is imperative. In lower pollution situation, the diurnal variation of PM was smoother, and its pollution sources were more regionally uniform, which might be attributed to the reduced diversity and complexity in the physical and chemical processes in air pollution.

14.
Front Med (Lausanne) ; 11: 1327505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500952

RESUMO

A patient presenting with several basal cell carcinomas, pigmented nevi, and developmental defects was diagnosed with nevoid basal cell carcinoma syndrome. Gene panel sequencing and Sanger sequencing were used to identify a novel heterozygous frameshift mutation, c.1312dupA:p.Ser438Lysfs, in exon 9 of PTCH1. I-Tasser and PyMol analyses indicated that the mutated protein patched homolog 1 (PTCH1) lacked 12 transmembrane domains and the intracellular and extracellular rings of ECD2 compared with the wild-type protein, resulting in a remarkably different structure from that of the wild-type protein. This case extends our knowledge of the mutation spectrum of NBCCS.

15.
Plant Sci ; 342: 112056, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438082

RESUMO

Most of mRNAs in Eukaryote were matured after the removal of introns in their pre-mRNA transcripts. Serine/arginine-rich (SR) proteins are a group of splicing regulators regulating the splicing processes globally. Expressions of SR proteins themselves were extensively regulated, at both transcription and splicing levels, under different environmental conditions, specially heat stress conditions. The pine genome is characterized by super-long and easily methylated introns in a large number of genes that derived from the extensive accumulation of transposons (TEs). Here, we identified and analyzed the phylogenetic characteristics of 24 SR proteins and their encoding genes from the pine genome. Then we explored transcription and pre-mRNA splicing expression patterns of SR genes in P. massoniana seedlings under normal and heat stress temperature conditions. Our results showed that the transcription patterns of SR genes in pine exhibited significant changes compared to other plant species, and these changes were not strictly correlated with the intron length and DNA methylation intensity of the SR genes. Interestingly, none of the long introns of SR genes underwent alternative splicing (AS) in our experiment. Furthermore, the intensity of AS regulation may be related to the potential DNA methylation intensity of SR genes. Taken together, this study explores for the first time the characteristics of significant variations in the transcription and splicing patterns of SR proteins in a plant species with an over-accumulation of super-long introns.


Assuntos
Arabidopsis , Precursores de RNA , Íntrons/genética , Precursores de RNA/genética , Filogenia , Arabidopsis/genética , Splicing de RNA , Processamento Alternativo/genética
16.
Chemphyschem ; : e202301002, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443312

RESUMO

By combining the advantages of dielectric barrier discharge (DBD) low temperature plasma and fluidized bed, the effect of plasma on the performance of supported Mo-based catalyst was studied in this paper. The performance of the catalyst obtained by plasma treatment, calcined, plasma+calcined was compared, and the appropriate catalyst preparation scheme was explored. Comparing with the three catalysts, it was concluded that the catalyst average conversion after 30 W plasma treatment is 33.40 %, which was 8.94 % and 12.75 % higher than the other two, respectively. The structure and properties of the catalyst were characterized by N2-Physisorption, H2-chemisorption, XRD, TEM, XPS, Raman and NO-pulse adsorption. Then, by analyzing the characterization results, it can be seen that plasma can make the catalyst have a higher specific surface area and a more dispersed active metal with smaller grain size. Through the surface species identification characterization, it was found that plasma can produce more defective structures and expose more active sites, which is the main reason for the difference in conversion.

17.
Small ; : e2311782, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38497813

RESUMO

With the development of electric vehicles, exploiting anode materials with high capacity and fast charging capability is an urgent requirement for lithium-ion batteries (LIBs). Borophene, with the merits of high capacity, high electronic conductivity and fast diffusion kinetics, holds great potential as anode for LIBs. However, it is difficult to fabricate for the intrinsic electron-deficiency of boron atom. Herein, heterogeneous-structured MoB2 (h-MoB2 ) with amorphous shell and crystalline core, is prepared by solid phase molten salt method. As demonstrated, crystalline core can encapsulate the honeycomb borophene within two adjacent Mo atoms, and amorphous shell can accommodate more lithium ions to strengthen the lithium storage capacity and diffusion kinetics. According to theoretical calculations, the lithium adsorption energy in MoB2 is about -2.7 eV, and the lithium diffusion energy barrier in MoB2 is calculated to be 0.199 eV, guaranteeing the enhanced adsorption capability and fast diffusion kinetic behavior of Li+ ions. As a result, h-MoB2 anode presents high capacity of 798 mAh g-1 at 0.1 A g-1 , excellent rate performance of 183 mAh g-1 at 5 A g-1 and long-term cyclic stability for 1200 cycles. This work may inspire ideas for the fabrication of borophene analogs and two-dimensional metal borides.

18.
J Pharm Biomed Anal ; 243: 116097, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489960

RESUMO

Brachial-ankle pulse wave velocity (baPWV) is a noninvasive index of vascular aging. However, the metabolic profile underlying vascular aging has not yet been fully elucidated. The current study aimed to identify circulating markers of vascular aging as assessed by baPWV and to elucidate its mechanism from a metabolomic perspective in older adults. A total of 60 and 61 Chinese male participants aged ≥80 years were recruited to the metabolome and validation cohorts, respectively. The baPWV of participants was measured using an automatic waveform analyzer. Plasma metabolic profile was investigated using ultra-performance liquid chromatography coupled with triple quadrupole linear ion trap tandem mass spectrometry. Orthogonal partial least squares (OPLS) regression modeling established the association between metabolic profile and baPWV to determine important metabolites predictive of vascular aging. Additionally, an enzyme-linked immunosorbent assay was employed to validate the metabolites in plasma and culture media of vascular smooth muscle cells in vitro. OPLS modeling identified 14 and 22 metabolites inversely and positively associated with baPWV, respectively. These 36 biomarkers were significantly enriched in seven metabolite sets, especially in cysteine and methionine metabolism (p <0.05). Notably, among metabolites involved in cysteine and methionine metabolism, S-adenosylmethionine (SAM) level was inversely related to baPWV, with a significant correlation coefficient in the OPLS model (p <0.05). Furthermore, the relationship between SAM and vascular aging was reconfirmed in an independent cohort and at the cellular level in vitro. SAM was independently associated with baPWV after adjustments for clinical covariates (ß = -0.448, p <0.001) in the validation cohort. In summary, plasma metabolomics identified an inverse correlation between SAM and baPWV in older males. SAM has the potential to be a novel biomarker and therapeutic target for vascular aging.


Assuntos
Índice Tornozelo-Braço , S-Adenosilmetionina , Humanos , Masculino , Idoso , Pressão Sanguínea , Cisteína , Análise de Onda de Pulso , Envelhecimento , Biomarcadores , Fatores de Risco
19.
J Hazard Mater ; 469: 133977, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38492395

RESUMO

The immunogenicity of haptens determines the performance of the resultant antibody for small molecules. Rigidity is one of the basic physicochemical properties of haptens. However, few studies have investigated the effect of hapten rigidity on the strength of an immune response and overall antibody performance. Herein, we introduce three molecular descriptors that quantify hapten rigidity. By using of these descriptors, four rifamycin haptens with varied rigidity were designed. The structural and physicochemical feasibility of the designed haptens was then assessed by computational chemistry. Immunization demonstrated that the strength of induced immune responses, i.e., the titer and affinity of antiserum, was significantly increased with increased rigidity of haptens. Furthermore, molecular dynamic simulations demonstrated conformation constraint of rigid haptens contributed to the initial binding and activation of naïve B cells. Finally, a highly sensitive indirect competitive enzyme-linked immunosorbent assay was developed for detection of rifaximin, with an IC50 of 1.1 µg/L in buffer and a limit of detection of 0.2-11.3 µg/L in raw milk, river water, and soil samples. This work provides new insights into the effect of hapten rigidity on immunogenicity and offers new hapten design strategies for antibody discovery and vaccine development of small molecules.


Assuntos
Anticorpos , Rifamicinas , Ensaio de Imunoadsorção Enzimática , Imunoensaio , Haptenos
20.
Stem Cell Res ; 76: 103328, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38335661

RESUMO

Fibroblasts were extracted from the scalp of a healthy 55-year-old male and subsequently transformed into pluripotent stem cells by introducing episomal plasmids harboring essential reprogramming factors. These induced pluripotent stem cells exhibited a normal karyotype and demonstrated the capacity to differentiate into all three germ layers, as confirmed through teratoma assays. This specific cell line serves as a valuable reference for comparative investigations alongside other induced pluripotent stem cell lines generated from somatic cells of patients afflicted by genetic neurodegenerative disorders.


Assuntos
Células-Tronco Pluripotentes Induzidas , Teratoma , Humanos , Masculino , Pessoa de Meia-Idade , Diferenciação Celular , Linhagem Celular , Reprogramação Celular , Fibroblastos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Plasmídeos , Teratoma/metabolismo
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