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1.
Chem Commun (Camb) ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742283

RESUMEN

Boron-incorporated nanosized HB-SUZ-4 showcased a noteworthy 24% boost in dimethyl ether carbonylation, with an elevation in methyl acetate selectivity from 91.8% to 96.0%. The improved performance is attributed to shortened diffusion lengths along the 8-member ring channels, decreased Brønsted acidity in the 10-member ring channels, and Lewis acid sites stabilizing CO.

2.
Microorganisms ; 12(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38674629

RESUMEN

The application of urea in agricultural soil significantly boosts nitrous oxide (N2O) emissions. However, the reason for nitrite accumulation, the period of nitrite-oxidizing bacteria (NOB) suppression, and the main NOB species for nitrite removal behind urea fertilization have not been thoroughly investigated. In this study, four laboratory microcosm experiments were conducted to simulate urea fertilization in agricultural soils. We found that within 36 h of urea application, nitrite oxidation lagged behind ammonia oxidation, leading to nitrite accumulation and increased N2O emissions. However, after 36 h, NOB activity recovered and then removed nitrite, leading to reduced N2O emissions. Urea use resulted in an N2O emission rate tenfold higher than ammonium. During incubation, Nitrobacter-affiliated NOB growth decreased initially but increased later with urea use, while Nitrospira-affiliated NOB appeared unaffected. Chlorate suppression of NOB lasted longer, increasing N2O emissions. Urease inhibitors effectively reduced N2O emissions by slowing urea hydrolysis and limiting free ammonia production, preventing short-term NOB suppression. In summary, short-term NOB suppression during urea hydrolysis played a crucial role in increasing N2O emissions from agricultural soils. These findings revealed the reasons behind the surge in N2O emissions caused by extensive urea application and provided guidance for reducing N2O emissions in agricultural production processes.

3.
Microorganisms ; 12(4)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38674747

RESUMEN

Lycopene represents one of the central compounds in the carotenoid pathway and it exhibits a potent antioxidant ability with wide potential applications in medicine, food, and cosmetics. The microbial production of lycopene has received increasing concern in recent years. Corynebacterium glutamicum (C. glutamicum) is considered to be a safe and beneficial industrial production platform, naturally endowed with the ability to produce lycopene. However, the scarcity of efficient genetic tools and the challenge of identifying crucial metabolic genes impede further research on C. glutamicum for achieving high-yield lycopene production. To address these challenges, a novel genetic editing toolkit, CRISPR/MAD7 system, was established and developed. By optimizing the promoter, ORI and PAM sequences, the CRISPR/MAD7 system facilitated highly efficient gene deletion and exhibited a broad spectrum of PAM sites. Notably, 25 kb of DNA from the genome was successfully deleted. In addition, the CRISPR/MAD7 system was effectively utilized in the metabolic engineering of C. glutamicum, allowing for the simultaneous knockout of crtEb and crtR genes in one step to enhance the accumulation of lycopene by blocking the branching pathway. Through screening crucial genes such as crtE, crtB, crtI, idsA, idi, and cg0722, an optimal carotenogenic gene combination was obtained. Particularly, cg0722, a membrane protein gene, was found to play a vital role in lycopene production. Therefore, the CBIEbR strain was obtained by overexpressing cg0722, crtB, and crtI while strategically blocking the by-products of the lycopene pathway. As a result, the final engineered strain produced lycopene at 405.02 mg/L (9.52 mg/g dry cell weight, DCW) in fed-batch fermentation, representing the highest reported lycopene yield in C. glutamicum to date. In this study, a powerful and precise genetic tool was used to engineer C. glutamicum for lycopene production. Through the modifications between the host cell and the carotenogenic pathway, the lycopene yield was stepwise improved by 102-fold as compared to the starting strain. This study highlights the usefulness of the CRISPR/MAD7 toolbox, demonstrating its practical applications in the metabolic engineering of industrially robust C. glutamicum.

4.
Micromachines (Basel) ; 15(4)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38675342

RESUMEN

The integration of advanced sensor technologies has significantly propelled the dynamic development of robotics, thus inaugurating a new era in automation and artificial intelligence. Given the rapid advancements in robotics technology, its core area-robot control technology-has attracted increasing attention. Notably, sensors and sensor fusion technologies, which are considered essential for enhancing robot control technologies, have been widely and successfully applied in the field of robotics. Therefore, the integration of sensors and sensor fusion techniques with robot control technologies, which enables adaptation to various tasks in new situations, is emerging as a promising approach. This review seeks to delineate how sensors and sensor fusion technologies are combined with robot control technologies. It presents nine types of sensors used in robot control, discusses representative control methods, and summarizes their applications across various domains. Finally, this survey discusses existing challenges and potential future directions.

5.
Int J Surg ; 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38597388

RESUMEN

BACKGROUND: The efficacy of laparoscopic completion total gastrectomy (LCTG) for remnant gastric cancer (RGC) remains controversial. METHODS: The primary outcome was postoperative morbidity within 30 days after surgery. Secondary outcomes included 3-year disease-free survival (DFS), 3-year overall survival (OS), and recurrence. Inverse probability treatment weighted (IPTW) was used to balance the baseline between LCTG and OCTG. RESULTS: Final analysis included 46 patients with RGC who underwent LCTG at the FJMUUH between June 2016 and June 2020. The historical control group comprised of 160 patients who underwent open completion total gastrectomy (OCTG) in the six tertiary teaching hospitals from CRGC-01 study. After IPTW, no significant difference was observed between the LCTG and OCTG groups in terms of incidence (LCTG vs. OCTG: 28.0% vs. 35.0%, P=0.379) or severity of complications within 30 days after surgery. Compared with OCTG, LCTG resulted in better short-term outcomes and faster postoperative recovery. However, the textbook outcome rate was comparable between the two groups (45.9% vs. 32.8%, P=0.107). Additionally, the 3-year DFS and 3-year OS of LCTG were comparable to those of OCTG (DFS: log-rank P=0.173; OS: log-rank P=0.319). No significant differences in recurrence type, mean recurrence time, or 3-year cumulative hazard of recurrence were observed between the two groups (all P>0.05). Subgroup analyses and concurrent comparisons demonstrated similar trends. CONCLUSIONS: This prospective study suggested that LCTG was non-inferior to OCTG in both short- and long-term outcomes. In experienced centers, LCTG may be considered as a viable treatment option for RGC.

6.
Adv Sci (Weinh) ; : e2308771, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477509

RESUMEN

Endotoxemia-related acute liver injury has a poor prognosis and high mortality, and macrophage polarization plays a central role in the pathological process. Pregnane X receptor (PXR) serves as a nuclear receptor and xenosensor, safeguarding the liver from toxic stimuli. However, the effect and underlying mechanism of PXR activation on endotoxemic liver injury remain largely unknown. Here, the expression of PXR is reported in human and murine macrophages, and PXR activation modified immunotypes of macrophages. Moreover, PXR activation significantly attenuated endotoxemic liver injury and promoted macrophage M2 polarization. Macrophage depletion by GdCl3 confirmed the essential of macrophages in the beneficial effects observed with PXR activation. The role of PXR in macrophages is further validated using AAV8-F4/80-Pxr shRNA-treated mice; the PXR-mediated hepatoprotection is impaired, and M2 polarization enhancement is blunted. Additionally, treatment with PXR agonists inhibited lipopolysaccharide (LPS)-induced M1 polarization and favored M2 polarization in BMDM, Raw264.7, and THP-1 cells. Further analyses revealed an interaction between PXR and p-STAT6 in vivo and in vitro. Moreover, blocking Pxr or Stat6 abolished the PXR-induced polarization shift. Collectively, macrophage PXR activation attenuated endotoxin-induced liver injury and regulated macrophage polarization through the STAT6 signaling pathway, which provided a potential therapeutic target for managing endotoxemic liver injury.

7.
Chem Biol Interact ; 393: 110970, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38513930

RESUMEN

Liver regeneration after liver tumor resection or liver transplantation is crucial, the remaining liver frequently fails to regenerate in some patients. Oleanolic acid (OA), a pentacyclic triterpenoid compound which has been shown to protect against various liver diseases. However, the effect of OA on liver regeneration after partial hepatectomy (PHx) is still unclear. In this study, the results showed that OA (50 mg/kg, twice daily) treatment induced liver mass restoration and increased the liver-to-body weight ratio of mice following PHx. Meanwhile, OA promoted hepatocyte proliferation and increased the number of BrdU-, Ki67-and PCNA-positive cells. Furthermore, OA increased the nuclear accumulation of PXR and induced the expression of PXR downstream proteins such as CYP3A11, UGT1A1 and GSTM2 in mice, as well as in AML12 and HepRG cells. Luciferase reporter assay and nuclear localization of PXR further demonstrated the effect of OA on PXR activation in vitro. Molecular docking simulation showed that OA could interact with the PXR active sites. Moreover, OA inhibited the expression of FOXO1, RBL2 and CDKN1B, and increased the expression of PCNA, CCND1 and CCNE1 in vivo and in vitro. Silencing of Pxr further confirmed that OA-mediated upregulation of proliferation-related proteins depended on PXR. The current study illustrated that OA exhibited a significant promoting effect on liver regeneration following PHx, potentially through regulation of the PXR signaling pathway to accelerate liver recovery.


Asunto(s)
Hepatectomía , Ácido Oleanólico , Humanos , Ratones , Animales , Regeneración Hepática , Receptor X de Pregnano/metabolismo , Ácido Oleanólico/farmacología , Hepatocitos , Antígeno Nuclear de Célula en Proliferación/metabolismo , Simulación del Acoplamiento Molecular , Hígado , Transducción de Señal , Ratones Endogámicos C57BL
8.
Surg Endosc ; 38(5): 2666-2676, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38512349

RESUMEN

BACKGROUND: Textbook outcome (TO) has been widely employed as a comprehensive indicator to assess the short-term prognosis of patients with cancer. Preoperative malnutrition is a potential risk factor for adverse surgical outcomes in patients with gastric cancer (GC). This study aimed to compare the TO between robotic-assisted gastrectomy (RAG) and laparoscopic-assisted gastrectomy (LAG) in malnourished patients with GC. METHODS: According to the diagnostic consensus of malnutrition proposed by Global Leadership Initiative on Malnutrition (GLIM) and Nutrition Risk Index (NRI), 895 malnourished patients with GC who underwent RAG (n = 115) or LAG (n = 780) at a tertiary referral hospital between January 2016 and May 2021 were included in the propensity score matching (PSM, 1:2) analysis. RESULTS: After PSM, no significant differences in clinicopathological characteristics were observed between the RAG (n = 97) and LAG (n = 194) groups. The RAG group had significantly higher operative time and lymph nodes harvested, as well as significantly lower blood loss and hospital stay time compared to the LAG group. More patients in the RAG achieved TO. Logistic regression analysis revealed that RAG was an independent protective factor for achieving TO. There were more adjuvant chemotherapy (AC) cycles in the RAG group than in the LAG group. After one year of surgery, a higher percentage of patients (36.7% vs. 22.8%; P < 0.05) in the RAG group recovered from malnutrition compared to the LAG group. CONCLUSIONS: For malnourished patients with GC, RAG performed by experienced surgeons can achieved a higher rate of TO than those of LAG, which directly contributed to better AC compliance and a faster restoration of nutritional status.


Asunto(s)
Gastrectomía , Laparoscopía , Desnutrición , Procedimientos Quirúrgicos Robotizados , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/complicaciones , Gastrectomía/métodos , Masculino , Femenino , Laparoscopía/métodos , Desnutrición/etiología , Procedimientos Quirúrgicos Robotizados/métodos , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Resultado del Tratamiento , Tiempo de Internación/estadística & datos numéricos , Tempo Operativo , Puntaje de Propensión
9.
Gastric Cancer ; 27(3): 598-610, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38379100

RESUMEN

BACKGROUND: Laparoscopy-assisted gastrectomy (LG) is rapidly gaining popularity owing to its minimal invasiveness. Previous studies have found that compared with two-dimensional (2D)-LG, three-dimensional (3D)-LG showed better short-term outcomes. However, the long-term oncological outcomes in patients with locally resectable gastric cancer (GC) remain controversial. METHODS: In this noninferiority, open-label, randomized clinical trial, a total of 438 eligible GC participants were randomly assigned in a 1:1 ratio to either 3D-LG or 2D-LG from January 2015 to April 2016. The primary endpoint was operating time, while the secondary endpoints included 5-year overall survival (OS), disease-free survival (DFS), and recurrence pattern. RESULTS: Data from 401 participants were included in the per-protocol analysis, with 204 patients in the 3D group and 197 patients in the 2D group. The 5-year OS and DFS rates were comparable between the 3D and 2D groups (5-year OS: 70.6% vs. 71.1%, Log-rank P = 0.743; 5-year DFS: 68.1% vs. 69.0%, log-rank P = 0.712). No significant differences were observed between the 3D and 2D groups in the 5-year recurrence rate (28.9% vs. 28.9%, P = 0.958) or recurrence time (mean time, 22.6 vs. 20.5 months, P = 0.412). Further stratified analysis based on the type of gastrectomy, postoperative pathological staging, and preoperative BMI showed that the 5-year OS, DFS, and recurrence rates of the 3D group in each subgroup were similar to those of the 2D group (all P > 0.05). CONCLUSIONS: For patients with locally resectable GC, 3D-LG performed by experienced surgeons in high-volume professional institutions can achieve long-term oncological outcomes comparable to those of 2D-LG. REGISTRATION NUMBER: NCT02327481 ( http://clinicaltrials.gov ).


Asunto(s)
Laparoscopía , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , Supervivencia sin Enfermedad , Supervivencia sin Progresión , Gastrectomía/métodos , Laparoscopía/métodos , Resultado del Tratamiento , Estudios Retrospectivos
10.
J Nanobiotechnology ; 22(1): 51, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321547

RESUMEN

BACKGROUND: Allergic rhinitis (AR) is a prevalent immune-related allergic disease, and corticosteroid nasal sprays serve as the primary treatment for this patient population. However, their short duration of efficacy and frequent administration pose challenges, leading to drug wastage and potential adverse effects. To overcome these limitations, we devised a novel approach to formulate DEX-Gel by incorporating dexamethasone (DEX) into a blend of Pluronic F127, stearic acid (SA), and polyethylene glycol 400 (PEG400) to achieve sustained-release treatment for AR. RESULTS: Following endoscopic injection into the nasal mucosa of AR rats, DEX-Gel exhibited sustained release over a 14-day period. In vivo trials employing various assays, such as flow cytometry (FC), demonstrated that DEX-Gel not only effectively managed allergic symptoms but also significantly downregulated helper T-cells (TH) 2 and TH2-type inflammatory cytokines (e.g., interleukins 4, 5, and 13). Additionally, the TH1/TH2 cell ratio was increased. CONCLUSION: This innovative long-acting anti-inflammatory sustained-release therapy addresses the TH1/TH2 immune imbalance, offering a promising and valuable approach for the treatment of AR and other inflammatory nasal diseases.


Asunto(s)
Rinitis Alérgica , Células TH1 , Humanos , Ratas , Animales , Ratones , Preparaciones de Acción Retardada/farmacología , Células Th2 , Rinitis Alérgica/tratamiento farmacológico , Citocinas , Antiinflamatorios/farmacología , Modelos Animales de Enfermedad , Ovalbúmina , Ratones Endogámicos BALB C
11.
J Colloid Interface Sci ; 660: 87-96, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38241874

RESUMEN

Germanium (Ge) nanomaterials have emerged as promising anode materials for lithium-ion batteries (LIBs) due to their higher capacity compared to commercial graphite. However, their practical application has been limited by the high cost associated with harsh preparation conditions and the poor electrode cycling stability in charging and diacharging. In this study, we successfully synthesized crystalline Ge nanorods through the reaction of intermetallic compound CaGe and ZnCl2. Ge nanorods with different morphologies and crystallinity can be obtained through precisely controlling the reaction temperature. When employed as electrodes for LIBs, the Ge nanorods demonstrate exceptional long-term cyclic stability. Even after 1000 cycles at a high rate of 2C (1C = 1600 mA g-1), it exhibits a remarkable reversible capacity of around 1000 mAh/g. Furthermore, such Ge electrode displays excellent cycling performance across a wide temperature range. And it could achieve reversible capacities of 1267, 832, and 690 mAh/g, with the rate of 1C, at temperatures of 20, 0, and -20 °C, respectively. Above all, our study offers a cost-effective approach for the synthesis of crystalline Ge nanorods, addressing the concerns associated with high production costs. And the application of Ge nanorods as anode materials in LIBs over a wide temperature range opens up new possibilities for the development of advanced energy storage systems.

12.
Angew Chem Int Ed Engl ; 63(8): e202316874, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38179842

RESUMEN

Converting CO2 to olefins is an ideal route to achieve carbon neutrality. However, selective hydrogenation to light olefins, especially single-component olefin, while reducing CH4 formation remains a great challenge. Herein, we developed ZnZrOx /SSZ-13 tandem catalyst for the highly selective hydrogenation of CO2 to light olefins. This catalyst shows C2 = -C4 = and propylene selectivity up to 89.4 % and 52 %, respectively, while CH4 is suppressed down to 2 %, and there is no obvious deactivation. It is demonstrated that the isolated moderate Brønsted acid sites (BAS) of SSZ-13 promotes the rapid conversion of intermediate species derived from ZnZrOx , thereby enhancing the kinetic coupling of the reactions and inhibit the formation of alkanes and improve the light olefins selectivity. Besides, the weaker BAS of SSZ-13 promote the conversion of intermediates into aromatics with 4-6 methyl groups, which is conducive to the aromatics cycle. Accordingly, more propene can be obtained by elevating the Si/Al ratio of SSZ-13. This provides an efficient strategy for CO2 hydrogenation to light olefins with high selectivity.

13.
J Chemother ; : 1-15, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38291982

RESUMEN

With the development of newer biomarkers in the diagnosis of gastric cancer (GC), therapeutic targets are emerging and molecular-targeted therapy is in progress RNA interference has emerged as a promising method of gene targeting therapy. However, naked small interfering RNA (siRNA) is unstable and susceptible to degradation, so employing vectors for siRNA delivery is the focus of our research. Therefore, we developed LMWP modified PEG-SS-PEI to deliver siRNA targeting BRD4 (L-NPs/siBRD4) for GC therapy. L-NPs/siBRD4 were prepared by electrostatic interaction and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The release characteristics, cellular uptake and intracellular localization were also investigated. The in vitro anticancer activity of the prepared nanoparticles was analysed by MTT, Transwell invasion and wound healing assay. Quantitative real time-polymerase chain reaction (qRT-PCR) and Western blot were used to detect the effect of gene silencing. The results showed that the optimal N/P was 30 and the prepared L-NPs/siBRD4 uniformly distributed in the system with a spherical and regular shape. L-NPs/siBRD4 exhibited an accelerated release in GSH-containing media from 12h to 24h. The uptake of L-NPs/siBRD4 was enhanced and mainly co-localized in the lysosomes. After 6h incubation, LMWP modified PEG-SS-PEI helped siRNA escape from the lysosomes and diffused into the cytoplasm. L-NPs/siBRD4 significantly inhibited the proliferation, migration and invasion of cells. This might be related with the silence of BRD4, then inhibition of PI3K/Akt and c-Myc. Our results demonstrate that L-NPs/siBRD4 are a novel delivery system with anticancer, which may provide a more effective strategy for GC treatment.

14.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37628762

RESUMEN

Phoebe bournei is nationally conserved in China due to its high economic value and positive effect on the ecological environment. P. bournei has an excellent wood structure, making it useful for industrial and domestic applications. Despite its importance, there are only a few studies on the lateral organ boundary domain (LBD) genes in P. bournei. The LBD gene family contributes to prompting rooting in multiple plant species and therefore supports their survival directly. To understand the LBD family in P. bournei, we verified its characteristics in this article. By comparing the sequences of Arabidopsis and identifying conserved domains and motifs, we found that there were 38 members of the LBD family in P. bournei, which were named PbLBD1 to PbLBD38. Through evolutionary analysis, we found that they were divided into two different populations and five subfamilies in total. The LBD gene family in P. bournei (Hemsl.) Yang species had two subfamilies, including 32 genes in Class I and 6 genes in Class II. It mainly consists of a Lateral Organ Boundary (LOB) conservative domain, and the protein structure is mostly "Y"-shaped. The gene expression pattern of the LBD gene family showed that the LBD genes were mainly expressed in lateral organs of plants, such as flowers and fruits. The response of LBD transcription factors to red and blue light was summarized, and several models of optogenetic expression regulation were proposed. The effect of regulatory mechanisms on plant rooting was also predicted. Moreover, quantitative real-time PCR (qRT-PCR) revealed that most PbLBDs were differentially expressed under cold, heat, drought, and salt stresses, indicating that PbLBDs might play different functions depending on the type of abiotic stress. This study provides the foundation for further research on the function of LBD in this tree species in the future.


Asunto(s)
Arabidopsis , Lauraceae , Evolución Biológica , China , Sequías
15.
J Colloid Interface Sci ; 650(Pt A): 236-246, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37406564

RESUMEN

Two-dimensional germanane (2D GeH) is considered to be a potential anode material for lithium-ion batteries (LIBs) due to the unique structure and properties. In this study, an effective method for synthesizing GeH is proposed, involving the etching of ball-milled CaGe2 with dilute hydrochloric acid at room temperature for a short duration. The resulting GeH nanosheets exhibit uniformity and high yield without the need for harsh reaction conditions or repeated ultrasound and centrifugation treatments. Comparative analysis reveals that GeH fabricated using this method exhibit superior cycling stability when employed as electrode in LIBs in comparison with reported techniques. Specifically, the as-prepared GeH anode can achieve a specific capacity of 1320 mAh/g after 400 cycles at 0.2C (1C = 1600 mAh/g) and 1020 mAh/g after 1000 cycles at 1C. Furthermore, GeH//LiFePO4 full cell is assembled for evaluating its practical applications. The specific capacity remains stable, maintaining 108 mAh/g after 140 cycles at a current density of 1C (1C = 170 mAh/g). The results confirm that the nano refinement process presented in this study effectively simplifies the synthesis process and significantly enhances the anode stability of GeH materials in LIBs applications. Importantly, this work provides a promising and versatile approach for the mass production of 2D electrode materials with improved electrochemical performance.

16.
J Biomol Struct Dyn ; : 1-8, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37505088

RESUMEN

Poly(ethylene terephthalate) (PET) has been widely utilized in daily life, but its non-degradability has induced severe environmental and health problems. Recently, PETase, which has been isolated from bacterium Ideonella sakaiensisis, was reported to have the highest PET degradation activity and specificity under room temperature, but no crystal structure for PET in complex with PETase has been reported. To provide deep insight into the binding mode of PET polymer on PETase and the binding interactions, we employed molecular docking and molecular dynamics simulations to study the substrate binding at the atomic level. Different PET oligomers have been studied with chain lengths varying from 2 to 8. In addition, the binding energies and hot-spot residues were analyzed to gain better insights into the binding mechanism by MM/GBSA approach. The PET oligomers adopt stable and reactive conformations in a shallow cleft on a flat surface of PETase. The binding cleft can only accommodate four moieties, and others beyond the region will be stabilized by the π-stacking interactions with Trp156 at the terephthalic acid terminal. Our studies provide a clear picture of how the binding mode of PET polymer and its interactions with PETase change with the chain length. Those studies would provide useful information for the rational design of catalytically more efficient PETase variants toward plastic degradation.Communicated by Ramaswamy H. Sarma.

17.
J Periodontal Res ; 58(5): 939-947, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37334752

RESUMEN

OBJECTIVE: To determine the critical roles of PU.1/cathepsin S activation in regulating inflammatory responses of macrophages during periodontitis. BACKGROUND: Cathepsin S (CatS) is a cysteine protease and exerts important roles in the immune response. Elevated CatS has been found in the gingival tissues of periodontitis patients and is involved in alveolar bone destruction. However, the underlying mechanism of CatS-driven IL-6 production in periodontitis remains unclear. METHODS: Western blot was applied to measure mature cathepsin S(mCatS) and IL-6 expression in gingival tissues from periodontitis patients and RAW264.7 cells exposed to lipopolysaccharide from Porphyromonas gingivalis (P.g. LPS). Immunofluorescence was applied to confirm the localization of PU.1, and CatS in the gingival tissues of periodontitis patients. ELISA was performed to determine IL-6 production by the P.g. LPS-exposed RAW264.7 cells. Knockdown by shRNA was used to determine the effects of PU.1 on p38/ nuclear factor (NF)-κB activation, mCatS expression and IL-6 production in RAW264.7 cells. RESULTS: The expressions mCatS and IL-6 were significantly upregulated in gingival macrophages. In cultured RAW264.7 cells, increased mCatS and IL-6 protein paralleled the activation of p38 and NF-κB after exposure to P.g. LPS. CatS knockdown by shRNA significantly decreased P.g. LPS-induced IL-6 expression and p38/NF-κB activation. PU.1 was significantly increased in P.g. LPS-exposed RAW264.7 cells, and PU.1 knockdown dramatically abolished the P.g. LPS-induced upregulation of mCatS and IL-6 and the activation of p38 and NF-κB. Furthermore, PU.1 and CatS colocalized in macrophages within the gingival tissues of periodontitis patients. CONCLUSION: PU.1-dependent CatS drives IL-6 production in macrophages by activating p38 and NF-κB in periodontitis.


Asunto(s)
FN-kappa B , Periodontitis , Humanos , FN-kappa B/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/farmacología , Periodontitis/metabolismo , Macrófagos , Porphyromonas gingivalis/metabolismo
18.
Adv Sci (Weinh) ; 10(24): e2302358, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37350571

RESUMEN

Designing and synthesizing advanced electrocatalysts with superior intrinsic activity toward hydrogen evolution reaction (HER) in alkaline media is critical for the hydrogen economy. Herein, a novel Ir@Rhene heterojunction electrocatalyst is synthesized via epitaxially confining ultrasmall and low-coordinate Ir nanoclusters on the ultrathin Rh metallene accompanying the formation of Ir/IrO2 Janus nanoparticles. The as-prepared heterojunctions display outstanding alkaline HER activity, with an overpotential of only 17 mV at 10 mA cm-2 and an ultralow Tafel slope of 14.7 mV dec-1 . Both structural characterizations and theoretical calculations demonstrate that the Ir@Rhene heterointerfaces induce charge density redistribution, resulting in the increment of the electron density around the O atoms in the IrO2 site and thus delivering much lower water dissociation energy. In addition, the dual-site synergetic effects between IrO2 and Ir/Rh interface trigger and improve the interfacial hydrogen spillover, thereby subtly avoiding the steric blocking of the active site and eventually accelerating the alkaline HER kinetics.

19.
Environ Sci Pollut Res Int ; 30(27): 70854-70870, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37156953

RESUMEN

Based on panel data from 285 Chinese prefecture-level cities from 2003 to 2020, this paper uses the difference-in-difference (DID) method to investigate the policy effect, mechanism, and heterogeneity of green finance (GF) to reduce environmental pollution. (1) Green finance has significant effect on reducing environmental pollution. The parallel trend test demonstrates that DID test results are valid. (2) Following a battery of robustness tests including instrumental variable, propensity score matching (PSM), variable substitution, and changing time-bandwidth, the conclusions are still valid. (3) Mechanism analysis reveals that green finance can reduce environmental pollution by increasing energy efficiency, adjusting industrial structure, and transforming green consumption. (4) Heterogeneity analysis proves that green finance has a substantial impact on reducing the environmental pollution in eastern and western cities, but not in central China. (5) In the "two-control zone" and "low-carbon pilot cities," the results of applying green finance policies are better, and a policy superposition effect exists. To be able to promote environmental pollution control, and green and sustainable development, this paper provides useful enlightenment for environmental pollution control for China and other similar countries.


Asunto(s)
Política Fiscal , Políticas , Ciudades , China , Contaminación Ambiental/prevención & control , Desarrollo Económico , Política Ambiental
20.
Iran J Public Health ; 52(3): 563-574, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37124914

RESUMEN

Background: Polarization of macrophages and miR-7 have been reported to greatly influence the progress of chronic obstructive pulmonary disease (COPD). However, the interaction is unclear. We aimed to investigate the role of miR-7 in the serum exosome of COPD, thus further revealing the underlying mechanism of COPD. Methods: The study was conducted in 2022 in The Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University, Changzhou, China. COPD mouse model was established. Macrophages were sorted by flow cytometry assay. ELISA kits were used to detect the levels of TNF-α and IL-6. Exosomes were identified by confocal microscopy and PKH67 staining. RT-qPCR and western blot assay were performed to determine the mRNA and protein expressions. H&E staining assay was used to assess the tissue injury. CCK-8 assay was applied to evaluate cell viability. Luciferase reporter assay was used to confirm the binding between PIM1 and miR-7. Results: The exosomes derived from the COPD mice serum exerted high level of miR-7, which induced M1 differentiation of macrophages and increased the secretion of proinflammatory factors in vivo and in vitro. The effects of exosomes from COPD mice could be inhibited by miR-7 inhibitor. Bioinformatic prediction, luciferase reporter assay, and western blot assay showed an interaction between miR-7 and PIM1. Further examination showed that miR-7 regulated macrophage activation and differentiation to M1 via PIM1 in vitro. Conclusion: miR-7 from serum exosomes might exacerbate COPD by stimulating macrophage differentiation to M1, supplying a potential therapeutic target for COPD treatment.

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