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1.
Redox Biol ; 72: 103158, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631121

RESUMO

Exposure to PM2.5 is correlated with cardiac remodeling, of which cardiac hypertrophy is one of the main clinical manifestations. Ferroptosis plays an important role in cardiac hypertrophy. However, the potential mechanism of PM2.5-induced cardiac hypertrophy through ferroptosis remains unclear. This study aimed to explore the molecular mechanism of cardiac hypertrophy caused by PM2.5 and the intervention role of MitoQ involved in this process. The results showed that PM2.5 could induce cardiac hypertrophy and dysfunction in mice. Meanwhile, the characteristics of ferroptosis were observed, such as iron homeostasis imbalance, lipid peroxidation, mitochondrial damage and abnormal expression of key molecules. MitoQ treatment could effectively mitigate these alternations. After treating human cardiomyocyte AC16 with PM2.5, ferroptosis activator (Erastin) and inhibitor (Fer-1), it was found that PM2.5 could promote ferritinophagy and lead to lipid peroxidation, mitochondrial dysfunction as well as the accumulation of intracellular and mitochondrial labile iron. Subsequently, mitophagy was activated and provided an additional source of labile iron, enhancing the sensitivity of AC16 cells to ferroptosis. Furthermore, Fer-1 alleviated PM2.5-induced cytotoxicity and iron overload in the cytoplasm and mitochondria of AC16 cells. It was worth noting that during the process of PM2.5 caused ferroptosis, abnormal iron metabolism mediated the activation of ferritinophagy and mitophagy in a temporal order. In addition, NCOA4 knockdown reversed the iron homeostasis imbalance and lipid peroxidation caused by PM2.5, thereby alleviating ferroptosis. In summary, our study found that iron homeostasis imbalance-mediated the crosstalk of ferritinophagy and mitophagy played an important role in PM2.5-induced ferroptosis and cardiac hypertrophy.

2.
Angew Chem Int Ed Engl ; : e202404886, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563659

RESUMO

The ion extraction and electro/photo catalysis are promising methods to address environmental and energy issues. Covalent organic frameworks (COFs) are a class of promising template to construct absorbents and catalysts because of their stable frameworks, high surface areas, controllable pore environments, and well-defined catalytic sites. Among them, ionic COFs as unique class of crystalline porous materials, with charges in the frameworks or along the pore walls, have shown different properties and resulting performance in these applications with those from charge-neutral COFs. In this review, current research progress based on the ionic COFs for ion extraction and energy conversion, including cationic/anionic materials and electro/photo catalysis is reviewed in terms of the synthesis strategy, modification methods, mechanisms of adsorption and catalysis, as well as applications. Finally, we demonstrated the current challenges and future development of ionic COFs in design strategies and applications.

3.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1602-1610, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621945

RESUMO

This study explored the mechanism of the ultrafiltration extract of Angelicae Sinensis Radix and Hedysari Radix in ameliorating renal fibrosis in the rat model of diabetic kidney disease(DKD) based on the expression of hypoxia-inducible factor-1α(HIF-1α)/vascular endothelial growth factor(VEGF) and HIF-1α/platelet-derived growth factor(PDGF)/platelet-derived growth factor receptor(PDGFR) signaling pathways in the DKD rats. After 1 week of adaptive feeding, 50 male SPF-grade Wistar rats were randomized into a blank group(n=7) and a modeling group. After 24 h of fasting, the rats in the modeling group were subjected to intraperitoneal injection of streptozocin and fed with a high-sugar and high-fat diet to establish a DKD model. After modeling, the rats were randomly assigned into model(n=7), low-dose ultrafiltration extract(n=7), medium-dose ultrafiltration extract(n=7), irbesartan(n=8), and high-dose ultrafiltration extract(n=8) groups. After intervention by corresponding drugs for 12 weeks, the general conditions of the rats were observed. The body weights and blood glucose levels of the rats were measured weekly, and the 24 h urinary protein(24hUP) was measured at the 6th and 12th weeks of drug administration. After the last drug administration, the renal function indicators were determined. Masson staining was employed to observe the pathological changes of the renal tissue. The expression of prolyl hydroxylase domain 2(PHD2) and HIF-1α in the renal tissue was detected by immunohistochemistry(IHC). Real-time qPCR was employed to determine the mRNA levels of PHD2, VEGF, PDGF, and PDGFR in the renal tissue. Western blot was employed to determine the protein levels of HIF-1α, VEGF, PDGF, and PDGFR in the renal tissue. The results showed that compared with the model group, drug administration lowered the levels of glycosylated serum protein(GSP), aerum creatinine(Scr), and blood urea nitrogen(BUN) in a dose-dependent manner(P<0.05 or P<0.01) and mitigated the pathological changes in the renal tissue. Furthermore, drug administration up-regulated mRNA level of PHD2(P<0.05 or P<0.01), down-regulated the mRNA levels of VEGF, PDGF, and PDGFR(P<0.05 or P<0.01) and the protein levels of HIF-1α, VEGF, PDGF, and PDGFR(P<0.01) in the renal tissue, and increased the rate of PHD2-positive cells(P<0.01). In conclusion, the ultrafiltration extract of Angelicae Sinensis Radix and Hedysari Radix effectively alleviated the renal fibrosis in DKD rats by inhibiting the expression of key proteins in the HIF-1α signaling pathway mediated by renal hypoxia and reducing extracellular matrix(ECM) deposition.


Assuntos
Nefropatias Diabéticas , Fator A de Crescimento do Endotélio Vascular , Ratos , Masculino , Animais , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ultrafiltração , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/genética , Fibrose , Hipóxia , Transdução de Sinais , RNA Mensageiro/metabolismo
4.
Front Public Health ; 12: 1335560, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638484

RESUMO

Objective: This study aimed to investigate the knowledge, attitude, and practice (KAP) regarding disinfection and hand hygiene, along with associated influencing factors among childcare facilities staff during the COVID-19 pandemic in Anhui, and to provide information for developing disinfection and hand hygiene strategies for childcare facilities. Methods: A web-based cross-sectional study was conducted among Anhui Province residents in China in September 2020. In this study, 60 childcare facilities in two cities of Anhui Province were selected using the convenient sampling method for questionnaires. The questionnaires were distributed through a web-based platform. The disinfection and hand hygiene KAP scores among childcare facilities staff were calculated, and their influencing factors were analyzed. The accuracy rates of knowledge, attitude, and practice of behavior were calculated and analyzed. Results: A total of 1,029 participants were included in the study. The disinfection and hand hygiene knowledge, attitude and practice ranged from approximately 5 to 23, 1 to 5, 3 to 13, respectively. The score of urban areas was higher than that of rural areas. Higher education levels and more years of working were associated with higher scores. Additionally, staff who received training or supervision had higher scores than those without. The categories with the lowest knowledge accuracy rate (46.3%), lowest attitude accuracy rate (4.2%), and "always" practice rate (5.3%) among childcare facility staff were all related to the question categories concerning the appropriate range of disinfectants for use. The accuracy rates of hand hygiene knowledge and attitude among the childcare facility staff were high (83.7%-99.6%), but the "always" practice rate was in the middle range (63.0%). Conclusion: The disinfection and hand hygiene knowledge among childcare facilities staff was inadequate during the COVID-19 pandemic in Anhui. Continuous implementation of education and training, particularly in rural areas, is essential. Establishing a monitoring system to assess usage effectiveness and adverse reactions in China is critical. Interventions should focus on increasing compliance with hand hygiene practices. Further research should explore the training and intervention of disinfection and hand hygiene, the safety of disinfection measures, and more operational hand hygiene methods in childcare facilities.


Assuntos
COVID-19 , Higiene das Mãos , Criança , Humanos , Higiene das Mãos/métodos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Transversais , Cuidado da Criança , Desinfecção , Conhecimentos, Atitudes e Prática em Saúde , Pandemias/prevenção & controle
5.
Ying Yong Sheng Tai Xue Bao ; 35(3): 622-630, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646749

RESUMO

Soil nitrogen and phosphorus are two key elements limiting tree growth in subtropical areas. Understanding the regulation of soil microorganisms on nitrogen and phosphorus nutrition is beneficial to reveal maintenance mechanism of soil fertility in plantations. We analyzed the characteristics of soil nitrogen and phosphorus fractions, soil microbial community composition and function, and their relationship across three stands of two-layered Cunninghumia lanceolata + Phoebe bournei with different ages (4, 7 and 11 a) and the pure C. lanceolata plantation. The results showed that the contents of most soil phosphorus fractions increased with increasing two-layered stand age. The increase in active phosphorus fractions with increasing stand age was dominated by the inorganic phosphorus (9.9%-159.0%), while the stable phosphorus was dominated by the organic phosphorus (7.1%-328.4%). The content of soil inorganic and organic nitrogen also increased with increasing two-layered stand age, with NH4+-N and acid hydrolyzed ammonium N contents showing the strongest enhancement, by 152.9% and 80.2%, respectively. With the increase of stand age, the composition and functional groups of bacterial and fungal communities were significantly different, and the relative abundance of some dominant microbial genera (such as Acidothermus, Saitozyma and Mortierella) increased. The relative abundance of phosphorus solubilization and mineralization function genes, nitrogen nitrification function and aerobic ammonia oxidation function genes tended to increase. The functional taxa of fungi explained 48.9% variation of different phosphorus fractions. The conversion of pure plantations to two-layered mixed plantation affected soil phosphorus fractions transformation via changing the functional groups of saprophytes (litter saprophytes and soil saprophytes). Changes in fungal community composition explained 45.0% variation of different nitrogen fractions. Some key genera (e.g., Saitozyma and Mortierella) play a key role in promoting soil nitrogen transformation and accumulation. Therefore, the conversion of pure C. lanceolata plantation to two-layered C. lanceolata + P. bournei plantation was conducive to improving soil nitrogen and phosphorus availability. Bacteria and fungi played important roles in the transformation process of soil nitrogen and phosphorus forms, with greater contribution of soil fungi.


Assuntos
Nitrogênio , Fósforo , Microbiologia do Solo , Solo , Fósforo/análise , Nitrogênio/análise , Nitrogênio/metabolismo , Solo/química , Cunninghamia/crescimento & desenvolvimento , China , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo
6.
Bioresour Technol ; 400: 130652, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38575096

RESUMO

The primary objective of this study is to explore the application of a deep eutectic solvent, synthesized from lactic acid and choline chloride, in combination with a pre-treatment involving ZSM-5 catalytic fast pyrolysis, aimed at upgrading the quality of bio-oil. Characterization results demonstrate a reduction in lignin content post-treatment, alongside a significant decrease in carboxyls and carbonyls, leading to an increase in the C/O ratio and noticeable enhancement in crystallinity. During catalytic fast pyrolysis experiments, the pre-treatment facilitates the production of oil fractions, achieving yields of 54.53% for total hydrocarbons and 39.99% for aromatics hydrocarbons under optimized conditions. These findings validate the positive influence of the deep eutectic solvent pre-treatment combined with ZSM-5 catalytic fast pyrolysis on the efficient production of bio-oil and high-value chemical derivatives. .

7.
Artigo em Inglês | MEDLINE | ID: mdl-38632039

RESUMO

The mutant strain H. bluephagenesis (TDH4A1B5P) was found to produce PHA under low-salt, non-sterile conditions, but the yield was low. To improve the yield, different nitrogen sources were tested. It was discovered that urea was the most effective nitrogen source for promoting growth during the stable stage, while ammonium sulfate was used during the logarithmic stage. The growth time of H. bluephagenesis (TDH4A1B5P) and its PHA content were significantly prolonged by the presence of sulfate ions. After 64 hours in a 5-liter bioreactor supplemented with sulfate ions, the dry cell weight of H. bluephagenesis weighed 132 g/l and had a PHA content of 82%. To promote the growth and PHA accumulation of H. bluephagenesis (TDH4A1B5P), a feeding regimen supplemented with nitrogen sources and sulfate ions with ammonium sodium sulfate was established in this study. The dry cell weight was 124 g/L, and the PHA content accounted for 82.3% (w/w) of the dry cell weight, resulting in a PHA yield of 101 g/L in a 30-liter bioreactor using the optimized culture strategy. In conclusion, stimulating H. bluephagenesis (TDH4A1B5P) to produce PHA is a feasible and suitable strategy for all H. bluephagenesis.

8.
BMC Med ; 22(1): 153, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609953

RESUMO

BACKGROUND: Prediction of lymph node metastasis (LNM) is critical for individualized management of papillary thyroid carcinoma (PTC) patients to avoid unnecessary overtreatment as well as undesired under-treatment. Artificial intelligence (AI) trained by thyroid ultrasound (US) may improve prediction performance. METHODS: From September 2017 to December 2018, patients with suspicious PTC from the first medical center of the Chinese PLA general hospital were retrospectively enrolled to pre-train the multi-scale, multi-frame, and dual-direction deep learning (MMD-DL) model. From January 2019 to July 2021, PTC patients from four different centers were prospectively enrolled to fine-tune and independently validate MMD-DL. Its diagnostic performance and auxiliary effect on radiologists were analyzed in terms of receiver operating characteristic (ROC) curves, areas under the ROC curve (AUC), accuracy, sensitivity, and specificity. RESULTS: In total, 488 PTC patients were enrolled in the pre-training cohort, and 218 PTC patients were included for model fine-tuning (n = 109), internal test (n = 39), and external validation (n = 70). Diagnostic performances of MMD-DL achieved AUCs of 0.85 (95% CI: 0.73, 0.97) and 0.81 (95% CI: 0.73, 0.89) in the test and validation cohorts, respectively, and US radiologists significantly improved their average diagnostic accuracy (57% vs. 60%, P = 0.001) and sensitivity (62% vs. 65%, P < 0.001) by using the AI model for assistance. CONCLUSIONS: The AI model using US videos can provide accurate and reproducible prediction of cervical lymph node metastasis in papillary thyroid carcinoma patients preoperatively, and it can be used as an effective assisting tool to improve diagnostic performance of US radiologists. TRIAL REGISTRATION: We registered on the Chinese Clinical Trial Registry website with the number ChiCTR1900025592.


Assuntos
Inteligência Artificial , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico por imagem
9.
Adv Sci (Weinh) ; : e2401515, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654624

RESUMO

Self-powered pressure detection using smart wearable devices is the subject of intense research attention, which is intended to address the critical need for prolonged and uninterrupted operations. Current piezoelectric and triboelectric sensors well respond to dynamic stimuli while overlooking static stimuli. This study proposes a dual-response potentiometric pressure sensor that responds to both dynamic and static stimuli. The proposed sensor utilizes interdigital electrodes with MnO2/carbon/polyvinyl alcohol (PVA) as the cathode and conductive silver paste as the anode. The electrolyte layer incorporates a mixed hydrogel of PVA and phosphoric acid. The optimized interdigital electrodes and sandpaper-like microstructured surface of the hydrogel electrolyte contribute to enhanced performance by facilitating an increased contact area between the electrolyte and electrodes. The sensor features an open-circuit voltage of 0.927 V, a short-circuit current of 6 µA, a higher sensitivity of 14 mV/kPa, and outstanding cycling performance (>5000 cycles). It can accurately recognize letter writing and enable capacitor charging and LED lighting. Additionally, a data acquisition and display system employing the proposed sensor, which facilitates the monitoring of athletes' rehabilitation training, and machine learning algorithms that effectively guide rehabilitation actions are presented. This study offers novel solutions for the future development of smart wearable devices.

10.
J Asian Nat Prod Res ; : 1-8, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600044

RESUMO

Two new triterpene fatty acid esters, 3ß-palmityloxy-12,27-cyclofriedoolean-14-en-11α-ol (1) and 3ß-palmityloxy-19α-hydroxyursane (2), together with 3ß-hydroxy-11-oxo-olean-12-enyl palmitate (3) were isolated from the potent anti-inflammatory active fraction of the petroleum ether-soluble part of Cirsium setosum ethanol extract. Compound 1 was found to be a rare 12,27-cyclopropane triterpenoid. Their structures were determined through spectral data analysis combined with literature reports. Furthermore, in vitro experiment, compounds 1-3 exhibited significant inhibitory effects on nitric oxide production in lipopolysaccharide-activated mouse RAW264.7 macrophages.

11.
Int Ophthalmol ; 44(1): 176, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619629

RESUMO

PURPOSE: Conventional diagnosis of primary open angle glaucoma (POAG) needs a combination of ophthalmic examinations. An efficient assay is urgently needed for a timely POAG diagnosis. We aim to explore differential expressions of circulating microRNAs (miRNA) and provide novel miRNA biomarkers for POAG diagnosis. METHODS: A total of 180 POAG patients and 210 age-related cataract (ARC) patients were enrolled. We collected aqueous humor (AH) and plasma samples from the recruited patients. The expressions of candidate miRNAs were measured using quantitative real time polymerase chain reaction. The diagnostic ability of candidate miRNAs was analyzed by receiver operating characteristic curve. RESULTS: The expressions of miR-21-5p and miR-29b-3p were downregulated significantly in AH and plasma of POAG and miR-24-3p expression was significantly increased in AH and plasma of POAG, comparing with those of ARC. A three-miRNA panel was constructed by a binary logistic regression. And the panel could differentiate between POAG and ARC with an area under the curve of 0.8867 (sensitivity = 78.0%, specificity = 83.3%) in aqueous humor and 0.7547 (sensitivity = 73.8%, specificity = 81.2%) in plasma. Next, we verified the three-miRNA panel working as a potential diagnostic biomarker stable and reliable. At last, we identified related function and regulation pathways in vitro. CONCLUSIONS: In conclusion, we built and identified a circulating three-miRNA panel as a potential diagnostic biomarker for POAG. It may be developed into an efficient assay and help improve the POAG diagnosis in the future.


Assuntos
MicroRNA Circulante , Glaucoma de Ângulo Aberto , MicroRNAs , Humanos , Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/genética , MicroRNAs/genética , Humor Aquoso , Biomarcadores
12.
Pestic Biochem Physiol ; 200: 105836, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582598

RESUMO

The striped stem borer, Chilo suppressalis (Walker), a notorious pest infesting rice, has evolved a high level of resistance to many commonly used insecticides. In this study, we investigate whether tyrosine hydroxylase (TH), which is required for larval development and cuticle tanning in many insects, could be a potential target for the control of C. suppressalis. We identified and characterized the full-length cDNA (CsTH) of C. suppressalis. The complete open reading frame of CsTH (MW690914) was 1683 bp in length, encoding a protein of 560 amino acids. Within the first to the sixth larval instars, CsTH was high in the first day just after molting, and lower in the ensuing days. From the wandering stage to the adult stage, levels of CSTH began to rise and reached a peak at the pupal stage. These patterns suggested a role for the gene in larval development and larval-pupal cuticle tanning. When we injected dsCsTH or 3-iodotyrosine (3-IT) as a TH inhibitor or fed a larva diet supplemented with 3-IT, there were significant impairments in larval development and larval-pupal cuticle tanning. Adult emergence was severely impaired, and most adults died. These results suggest that CsTH might play a critical role in larval development as well as larval-pupal tanning and immunity in C. suppressalis, and this gene could form a potential novel target for pest control.


Assuntos
Inseticidas , Mariposas , Oryza , Animais , Larva/genética , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo , Pupa , Mariposas/metabolismo , Oryza/metabolismo
13.
Neurosurgery ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619238

RESUMO

BACKGROUND AND OBJECTIVES: Venous hypertensive myelopathy (VHM), mainly induced by the spinal dural arteriovenous fistula, is a congestive spinal cord injury that currently has no appropriate animal model available in preclinical research. METHODS: Sprague Dawley rats (280-320 g) were used. The rats were divided into 3 groups: (1) Group 1, which underwent renal artery-dorsal spinal venous bypass (AVB group); (2) Group 2, which underwent renal artery-dorsal spinal venous bypass and drainage vein stenosis (AVB/VS group); and (3) Control group, with T13 dorsal vein ligation. The success of the model was assessed using Doppler ultrasound and 7.0-T magnetic resonance imaging. Transmission electron microscopy, histochemistry, proteomics, and western blot analysis were used to evaluate ultrastructural, pathological, and molecular features in the spinal cord and cerebrospinal fluid (CSF). RESULTS: The success rate of the arteriovenous bypass was 100% at 5 days and 83% at 2 weeks. The locomotor assessment showed decreased lower extremity strength in the AVB/VS group (P = .0067), whereas unremarkable changes were found in the AVB and Control groups. Histochemical staining suggested a 2-fold expansion of the dorsal spinal vein in the AVB/VS group, which was lower than that in the AVB group (P < .05); however, the former displayed greater myelin and neuronal damage (P < .05) and slight dilatation of the central canal (P > .05). Proteomics analysis revealed that the complement and coagulation cascade pathways were upregulated in the CSF of AVB/VS rats, whereas the C3 level was elevated both in the CSF and bilateral spinal cord. Furthermore, overexpression of C3, ITGB2, and CD9 in the spinal cord was confirmed by immunoblotting. CONCLUSION: These findings suggest that the AVB/VS model can effectively mimic the clinical and molecular characteristics of VHM. Furthermore, they suggest that impaired deep intramedullary venous drainage is the key reason for the VHM.

14.
Front Vet Sci ; 11: 1383801, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601914

RESUMO

The objective of this study was to investigate the protective effect of Crataegus pinnatifida polysaccharide (CPP) on non-alcoholic fatty liver disease (NAFLD) induced by a high-fat diet (HFD) in mice. The findings demonstrated that CPP improved free fatty acid (FFA)-induced lipid accumulation in HepG2 cells and effectively reduced liver steatosis and epididymal fat weight in NAFLD mice, as well as decreased serum levels of TG, TC, AST, ALT, and LDL-C. Furthermore, CPP exhibited inhibitory effects on the expression of fatty acid synthesis genes FASN and ACC while activating the expression of fatty acid oxidation genes CPT1A and PPARα. Additionally, CPP reversed disturbances in intestinal microbiota composition caused by HFD consumption. CPP decreased the firmicutes/Bacteroidetes ratio, increased Akkermansia abundance, and elevated levels of total short-chain fatty acid (SCFA) content specifically butyric acid and acetic acid. Our results concluded that CPP may intervene in the development of NAFLD by regulating of intes-tinal microbiota imbalance and SCFAs production. Our study highlights that CPP has a potential to modulate lipid-related pathways via alterations to gut microbiome composition thereby ex-erting inhibitory effects on obesity and NAFLD development.

15.
Angew Chem Int Ed Engl ; : e202405763, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607321

RESUMO

Photocatalytic oxygen reduction reactions and water oxidation reactions are extremely promising green approaches for massive H2O2 production. Nonetheless, constructing effective photocatalysts for H2O2 generation is critical and still challenging. Since the network topology has significant impacts on the electronic properties of two dimensional (2D) polymers, herein, for the first time, we regulated the H2O2 photosynthetic activity of 2D covalent organic frameworks (COFs) by topology. Through designing the linking sites of the monomers, we synthesized a pair of novel COFs with similar chemical components on the backbones but distinct topologies. Without sacrificial agents, TBD-COF with cpt topology exhibited superior H2O2 photoproduction performance (6085 and 5448 µmol g-1 h-1 in O2 and air) than TBC-COF with hcb topology through the O2-O2•--H2O2, O2-O2•--O21-H2O2, and H2O-H2O2 three paths. Further experimental and theoretical investigations confirmed that during the H2O2 photosynthetic process, the charge carrier separation efficiency, O2•- generation and conversion, and the energy barrier of the rate determination steps in the three channels, related to the formation of *OOH, *O21, and *OH, can be well tuned by the topology of COFs. The current study enlightens the fabrication of high-performance photocatalysts for H2O2 production by topological structure modulation.

16.
Abdom Radiol (NY) ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478038

RESUMO

RATIONALE AND OBJECTIVES: The study aimed to investigate whether dynamic contrast-enhanced MRI parameters and preoperative radiological features (DCER-Features) add value to the clinicopathologic model for predicting metachronous metastases in rectal cancer patients. MATERIALS AND METHODS: From January 2014 to December 2020, 859 patients in the PACS system were retrospectively screened. Of the initial 722 patients with surgically confirmed rectal cancer and no synchronous metastases, 579 patients were excluded for various reasons such as lack of clinicopathological or radiological information. 143 patients were finally included in this study. And 73 Patients of them developed metachronous metastasis within five years. After stepwise multiple regression analyses, we constructed three distinct models. Model 1 was developed solely based on clinicopathological factors, and model 2 incorporated clinicopathological characteristics along with DCE-MRI parameters. Finally, model 3 was built on all available factors, including clinicopathological characteristics, DCE-MRI parameters, and radiological features based on rectal magnetic resonance imaging. The radiological features assessed in this study encompass tumor imaging staging, location, and circumferential resection margin (CRM) for primary tumors, as well as the number of visible lymph nodes and suspected metastatic lymph nodes. Receiver operating characteristic (ROC) and decision curve analysis (DCA) were conducted to evaluate whether the diagnostic efficiency was improved. RESULTS: The performance of model 3 (including clinicopathologic characteristics and DCER-Features) was the best (AUC: 0.856, 95% CI 0.778-0.886), whereas it was 0.796 (95% CI 0.720-0.828) for model 2 and 0.709 (95% CI 0.612-0.778) for model 1 (DeLong test: model 1 vs model 2, p = 0.004; model 2 vs model 3, p = 0.037; model 1 vs model 3, p < 0.001). The decision curves indicated that the net benefit of model 3 was higher than the other two models at each referral threshold. The calibration plot of the three models revealed an excellent predictive accuracy. CONCLUSION: This study suggests that DCER-Features have added value for the clinicopathological model to predict metachronous metastasis in patients with rectal cancers.

17.
Huan Jing Ke Xue ; 45(3): 1760-1768, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471887

RESUMO

In order to explore the status of soil heavy metal pollution and environmental quality in west Hunan, relevant areas of Phoenix County were selected as the study area. Using data from 440 soil samples collected in the study area from June to August 2022, the pH value of the soil and contents of eight heavy metal elements, namely, As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, were analyzed. The PMF model was used for traceability analysis and geochemical evaluation of soil environmental quality. The results showed that the average values of soil heavy metals ω(Zn), ω(Cr), ω(Pb), ω(Ni), ω(Cu), ω(As), ω(Cd), and ω(Hg) were 81.02, 64.67, 31.63, 29.27, 25.52, 9.93, 0.28, and 0.13 mg·kg-1, respectively. The soil in the study area was mainly weakly acidic, and the contents of the Cd and Hg elements were relatively high compared to the national soil background values and were highly variable. The contents of the Hg and Cd elements in forest land were higher than that in other land uses. The PMF model results showed that the contribution rates of heavy metal pollution sources in the study area were mining sources (37.4%), atmospheric sedimentation sources (7.7%), natural sources (41.1%), and agricultural activity sources (13.8%) and provided suggestions on pollution control measures according to the spatial distribution of the four types of pollution sources. Through the comprehensive assessment of soil environmental geochemistry, the study area was divided into three types of plots, namely, non-risk areas (94.27 km2), accounting for 76.38%; risk-controllable areas (27.45 km2), accounting for 22.24%; and high-risk areas (1.7 km2), accounting for 1.38%. This study provided data support for the prevention and control measures of land pollution in the research area, as well as the delineation of the prevention and control scope.

18.
Huan Jing Ke Xue ; 45(2): 952-960, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471933

RESUMO

In order to clarify the impact of no-tillage on the quality of farmland soil aggregates in China and promote the adaptive application of no-tillage practices, a Meta-analysis was conducted by collecting data from 116 published studies. The effects of no-tillage on aggregate size distribution, mean weight diameter (MWD), and aggregate-associated C were studied. The results showed that compared with that under tillage, no-tillage significantly increased the proportion of macroaggregates (10.9%) and MWD (12.8%) and decreased the proportion of clay and silt (-15.5%) but had no significant effect on soil microaggregate and aggregate-associated C. The subgroup and Meta regression analysis showed that no-tillage significantly increased the proportion of macroaggregates in Northwest China (17.6%) and MWD in North China (15.4%). In upland and clay loam, no-tillage increased MWD by 12.6% and 18.4%, respectively. The effect of no-tillage on increasing the proportion of macroaggregates increased with the soil pH. When straw returned, no-tillage significantly increased the proportion of macroaggregates (9.6%) and MWD (11.6%), but no significant effect of no-tillage on aggregates was found after straw removal. Regarding test duration, short-term ( < 5 a) no-tillage could significantly increase the proportion of macroaggregates, whereas long-term ( > 10 a) no-tillage could improve the MWD. In different soil layers, no-tillage could only significantly improve the aggregate size distribution and MWD in topsoil (0-20 cm) but had no effect in subsoil ( > 20 cm). In summary, no-tillage could improve aggregate size distribution and stability but had no effect on aggregate-associated C. Production region, soil properties, field management methods, and other factors should be fully considered in production practice to effectively improve the quality of soil aggregates.

19.
Appl Environ Microbiol ; 90(4): e0000824, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38506527

RESUMO

Currently, the L-malic acid titer achieved through Aspergillus niger fermentation reaches 201 g/L, meeting industrial demands satisfactorily. However, the co-presence of structurally similar fumaric acid and succinic acid in fermentation products suggests a theoretical potential for further improvement in L-malic acid production. In the tricarboxylic acid cycle, fumarate reductase mediates the conversion of succinic acid to fumaric acid. Subsequently, fumarase catalyzes the conversion of fumaric acid to L-malic acid. Notably, both enzymatic reactions are reversible. Our investigation revealed that A. niger contains only one mitochondria-located fumarase FumA. Employing CRISPR-Cas9 technology, we performed a replacement of the fumA promoter with a doxycycline-induced promoter Tet. Under non-inducing condition, the conditional strain exhibited increased levels of fumaric acid and succinic acid. It strongly suggests that FumA mainly promotes the flow of fumaric acid to L-malic acid. Furthermore, a promoter PmfsA that is exclusively activated in a fermentation medium by calcium carbonate was identified through RNA-sequencing screening. Utilizing PmfsA to regulate fumA expression led to a 9.0% increase in L-malic acid titer, an 8.75% increase in yield (glucose to L-malic acid), and an 8.86% enhancement in productivity. This research serves as a significant step toward expediting the industrialization of L-malic acid synthesis via biological fermentation. Additionally, it offers valuable insights for the biosynthesis of other organic acids.IMPORTANCEThis study focuses on enhancing L-malic acid synthesis by modifying the tricarboxylic acid cycle within the mitochondria of Aspergillus niger. We emphasize the significant role of fumarase in converting fumaric acid into L-malic acid, enhancing our understanding of metabolic pathways in A. niger. The precise regulation of fumA is highlighted as a key factor in enhancing L-malic acid production. Furthermore, this research introduces a stringent conditional promoter (PmfsA), exclusively activated by CaCO3. The utilization of PmfsA for fumA expression resulted in heightened L-malic acid titers. The progress in metabolic engineering and bioprocess optimization holds promise for expediting industrial L-malic acid synthesis via biological fermentation. Moreover, it carries implications for the biosynthesis of various other organic acids.


Assuntos
Aspergillus niger , Fumarato Hidratase , Fumaratos , Aspergillus niger/genética , Aspergillus niger/metabolismo , Fumarato Hidratase/genética , Fumarato Hidratase/metabolismo , Malatos/metabolismo , Ácido Succínico
20.
ACS Appl Mater Interfaces ; 16(13): 17051-17061, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511856

RESUMO

Luminescent perovskite nanocrystals (NCs), possessing the advantages of low cost, easy detection, and excellent luminescence, are becoming more and more significant in the fields of information encryption and decryption. Most hydrochromic perovskite NCs for information encryption have moderate reversibility and are easily passively decrypted by water in the moist air, limiting their practical applications. Herein, a lyochromic material is synthesized based on reversible phase transition between luminescent CsPbBr3-HBr (pretreating CsPbBr3 with HBr) and nonluminescent Cs4PbBr6, exhibiting excellent reversibility in 50 cycles triggered by CsBr solution. HBr treatment boosts the ion migration of NCs via diminishing surface ligands and passivating Br vacancy, assisting CsBr concentration acting as a crucial factor in dynamic ion exchange equilibrium between the trigger solution and CsPbBr3-HBr. By utilizing CsPbBr3-HBr as a safety ink, the CsBr-triggered photoluminescence switch has been demonstrated to be reproducible, stable, and reliable for information encryption and decryption.

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