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1.
Inorg Chem ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333885

RESUMO

The reasonable design and modulation of the electronic properties of Pd metallene are acknowledged as a promising avenue for enhancing the oxygen reduction reaction (ORR) in anion exchange membrane fuel cells (AEMFCs), yet they remain a formidable challenge. Herein, a thin-sheet structure of Zr-doped Pd metallene (PdZr metallene) with abundant defects is proposed using a facile wet-chemical approach for efficient and highly durable ORR electrocatalysis. Multiple microstructural analyses uncover that orchestrated electronic and oxophilic regulation of PdZr metallene via Lewis-acidic Zr site modulation could concurrently optimize the electronic configuration of Pd, downshift the d-band center of Pd, and, thus, promote the intrinsic activity. Benefiting from the unique two-dimensional morphology and electronic structure optimization facilitated by the Zr coupling effect, the resultant PdZr metallene demonstrates significantly enhanced ORR electrocatalytic performance in basic solutions, with a high half-wave potential (E1/2) of 0.87 V and commendable stability for 30 000 s, surpassing those of Pd metallene and various advanced Pd-based catalysts reported in the literature. Encouragingly, the PdZr metallene-based AEMFC achieves an increased maximum power density (90.4 mW cm-2) and impressive robustness over 12 h in an alkaline environment, manifesting the practical application of PdZr metallene in AEMFCs. This study showcases the applicability of PdZr metallene via Lewis acid site regulation for fabricating highly active electrocatalysts for high-performance AEMFCs.

2.
Cyborg Bionic Syst ; 5: 0128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38938902

RESUMO

Brain-inspired navigation technologies combine environmental perception, spatial cognition, and target navigation to create a comprehensive navigation research system. Researchers have used various sensors to gather environmental data and enhance environmental perception using multimodal information fusion. In spatial cognition, a neural network model is used to simulate the navigation mechanism of the animal brain and to construct an environmental cognition map. However, existing models face challenges in achieving high navigation success rate and efficiency. In addition, the limited incorporation of navigation mechanisms borrowed from animal brains necessitates further exploration. On the basis of the brain-inspired navigation process, this paper launched a systematic study on brain-inspired environment perception, brain-inspired spatial cognition, and goal-based navigation in brain-inspired navigation, which provides a new classification of brain-inspired cognition and navigation techniques and a theoretical basis for subsequent experimental studies. In the future, brain-inspired navigation technology should learn from more perfect brain-inspired mechanisms to improve its generalization ability and be simultaneously applied to large-scale distributed intelligent body cluster navigation. The multidisciplinary nature of brain-inspired navigation technology presents challenges, and multidisciplinary scholars must cooperate to promote the development of this technology.

3.
Cell Mol Gastroenterol Hepatol ; 15(5): 1255-1275, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36706918

RESUMO

BACKGROUND & AIMS: Many studies have revealed crucial roles of the gut microbiota and its metabolites in liver disease progression. However, the mechanism underlying their effects on liver ischemia/reperfusion (I/R) injury remain largely unknown. Here, we investigate the function of gut microbiota and its metabolites in liver I/R injury. METHODS: C57BL/6 mice was pretreated with an antibiotic cocktail. Then, we used multi-omics detection methods including 16s rRNA sequencing, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) to explore the changes of gut microbiota and metabolites in both feces and portal blood to reveal the mechanism of their protective effect in liver I/R injury. RESULTS: We found that antibiotic pretreatment (ABX) could significantly reduce the severity of I/R-induced hepatic injury, and this effect could be transferred to germ-free mice by fecal microbiota transplantation (FMT), suggesting a protective role of the gut microbiota depletion. During I/R, the rates of serum α-ketoglutarate (αKG) production and glutamate reduction, downstream products of gut microbiota-derived glutamine, were more significant in the ABX mice. Then, we showed that αKG could promote alternative (M2) macrophage activation through oxidative phosphorylation, and oligomycin A could inhibit M2 macrophage polarization and reversed this protective effect. CONCLUSIONS: These findings show that the gut microbiota and its metabolites play critical roles in hepatic I/R injury by modulating macrophage metabolic reprogramming. Potential therapies that target macrophage metabolism, including antibiotic therapies and novel immunometabolism modulators, can be exploited for the treatment of liver I/R injury.


Assuntos
Microbioma Gastrointestinal , Traumatismo por Reperfusão , Camundongos , Animais , Glutamina/farmacologia , Glutamina/metabolismo , RNA Ribossômico 16S , Cromatografia Líquida , Espectrometria de Massas em Tandem , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Macrófagos/metabolismo , Traumatismo por Reperfusão/metabolismo , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Isquemia/metabolismo
4.
Front Pediatr ; 11: 1141665, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37009295

RESUMO

Objective: To share our experience on prenatal diagnosis of Williams-Beuren syndrome(WBS) and to improve the awareness, diagnosis, and intrauterine monitoring of the fetuses of this disease. Methods: The study retrospectively evaluated 14 cases of WBS diagnosed prenatally by single nucleotide polymorphism array (SNP-array). Clinical data from these cases were systematically reviewed, including maternal demographics, indications for invasive prenatal diagnosis, ultrasound findings, SNP-array results, trio-medical exome sequencing (Trio-MES) results, QF-PCR results, pregnancy outcomes and follow-ups. Results: A total of 14 fetuses were diagnosed with WBS and their prenatal phenotypes were assessed retrospectively. In our case series, the most common ultrasound features were intrauterine growth retardation (IUGR), congenital cardiovascular defects, abnormal fetal placental doppler indices, thickened nuchal translucency(NT) and polyhydramnios. Other less common ultrasound features include fetal hydrops, hydroderma, bilateral pleural effusion, subependymal cysts, etc. Parental chromosome analysis was performed in seven pairs of parents, and all the deletions on chromosome 7q11.23 were de novo. Conclusion: Prenatal ultrasound features of WBS cases are highly variable, with IUGR, cardiovascular abnormalities and abnormal fetal placental doppler indices, being the most common intrauterine phenotypes. Our case series expand the intrauterine phenotypes of WBS, including cardiovascular abnormalities right aortic arch(RAA) combined with persistent right umbilical vein(PRUV) and elevated the ratio of end-systolic peak flow velocity to end-diastonic peak flow velocity(S/D). In the meantime, with the decrease in the cost of the next-generation sequencing, the method may become widely used in prenatal diagnosis in the near future.

5.
J Huazhong Univ Sci Technolog Med Sci ; 32(6): 883-887, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23271291

RESUMO

This study examined the anti-viral effect of ursolic acid on guinea pig cytomegalovirus (GPCMV) and explored the steps of viral replication targeted by ursolic acid. Cytopathic effect assay and MTT method were employed to determine the 50% cellular cytotoxicity (CC(50)), 50% effective concentration (EC(50)) and therapeutic index (TI) with GPCMV. To investigate the specific anti-viral effect of ursolic acid at different temperatures and time points, two other medicines, ganciclovir and Jinyebaidu (JYBD), serving as controls, were studied for comparison. Our results showed that the CC50 of ganciclovir, JYBD and ursolic acid were 333.8, 3015.6, 86.7 µg/mL, respectively; EC(50) of ganciclovir, JYBD and ursolic acid was 48.1, 325.5 and 6.8 µg/mL, respectively; TI of ganciclovir, JYBD and ursolic acid was 7, 9, 13, respectively. Similar with ganciclovir, ursolic acid could inhibit the viral synthesis, but did not affect the viral adsorption onto and penetration into cells. We are led to conclude that the anti-cytomegalovirus effect of ursolic acid is significantly stronger than ganciclovir or JYBD, and the cytotoxic effect of ursolic acid lies in its ability to inhibit viral synthesis.


Assuntos
Antivirais/farmacologia , Roseolovirus/efeitos dos fármacos , Triterpenos/farmacologia , Animais , Células Cultivadas , Cobaias , Ácido Ursólico
6.
Mol Genet Metab ; 102(2): 194-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21056935

RESUMO

Hematopoietically expressed homeobox (HHEX) gene encodes for a transcription factor involved in Wnt/ß-catenin signaling pathway which has attracted considerable attention as a candidate gene for type 2 diabetes (T2D) since it was first identified through genome wide association approach. The relationship between HHEX and T2D has been reported in various ethnic groups; however, these studies have yielded contradictory results. To investigate this inconsistency, we performed a meta-analysis of 26 studies involving a total of 110,875 subjects for rs1111875 of the HHEX gene to evaluate the effect of HHEX on genetic susceptibility for T2D. An overall random effects odds ratio of 1.16 (95% CI: 1.13-1.20) was found for C allele versus T allele. Significant results were also observed using dominant (OR=1.21, 95% CI: 1.16-1.25) or recessive genetic model (OR=1.24, 95% CI: 1.18-1.30). There was strong evidence of heterogeneity (P<0.001), which largely disappeared after stratification by ethnicity. In the subgroup analysis by sample size, source of controls and diagnostic criterion, significantly increased risks were found for the polymorphism in all genetic models. This meta-analysis demonstrated that the C allele of rs1111875 of HHEX is a risk factor associated with increased T2D susceptibility, but these associations vary in different ethnic populations.


Assuntos
Diabetes Mellitus Tipo 2/genética , Hematopoese/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Alelos , Diabetes Mellitus Tipo 2/etnologia , Predisposição Genética para Doença , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Medição de Risco
7.
Toxicol Res (Camb) ; 10(4): 875-884, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34484679

RESUMO

Cervical cancer (CC) is a type of pelvic malignant tumor that severely threatens women's health. Current evidence suggests that IER5, as a potential radiosensitizer, promotes irradiation-induced apoptosis in CC tissues in patients undergoing chemoradiotherapy. IER5 has been shown to be involved in the G2/M-phase transition. In the present study, we used Cdc25B as the breakthrough point to explore the underlying mechanism of IER5 in the cell cycle regulation of radiation-damaged HeLa cells. IER5 was evidently upregulated after irradiation, but Cdc25B was significantly downregulated. In monoclonal IER5-silenced HeLa cells, irradiation-induced downregulation of Cdc25B was attenuated. The effect of irradiation on Cdc25B promoter activity was determined by dual-luciferase reporter assays. The response elements on the Cdc25B promoter related to irradiation were predicted by JASPAR. These conserved sequences were mutated individually or in combination by splicing-by-overlap extension PCR, and their function was confirmed by dual-luciferase reporter assays. The enrichment efficiency of transcription factors after irradiation was determined by chromatin immunoprecipitation (ChIP) assay. Both Sp1/Sp3 and NF-YB binding sites were involved in irradiation-mediated regulation of Cdc25B. IER5 was involved in irradiation-mediated regulation of Cdc25B through the NF-YB binding site. Furthermore, ChIP assays showed that IER5 bound to the Cdc25B promoter, and the binding of IER5 to the Cdc25B promoter region in irradiation-induced HeLa cells induced the release of the coactivator p300 through interaction with NF-YB. Taken together, these findings indicate that IER5 is the transcriptional repressor that accelerates the downregulation of Cdc25B expression after irradiation.

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