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1.
Adv Mater ; 36(27): e2401133, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38619914

ABSTRACT

The electrochemical reduction of nitrates (NO3 -) enables a pathway for the carbon neutral synthesis of ammonia (NH3), via the nitrate reduction reaction (NO3RR), which has been demonstrated at high selectivity. However, to make NH3 synthesis cost-competitive with current technologies, high NH3 partial current densities (jNH3) must be achieved to reduce the levelized cost of NH3. Here, the high NO3RR activity of Fe-based materials is leveraged to synthesize a novel active particle-active support system with Fe2O3 nanoparticles supported on atomically dispersed Fe-N-C. The optimized 3×Fe2O3/Fe-N-C catalyst demonstrates an ultrahigh NO3RR activity, reaching a maximum jNH3 of 1.95 A cm-2 at a Faradaic efficiency (FE) for NH3 of 100% and an NH3 yield rate over 9 mmol hr-1 cm-2. Operando XANES and post-mortem XPS reveal the importance of a pre-reduction activation step, reducing the surface Fe2O3 (Fe3+) to highly active Fe0 sites, which are maintained during electrolysis. Durability studies demonstrate the robustness of both the Fe2O3 particles and Fe-Nx sites at highly cathodic potentials, maintaining a current of -1.3 A cm-2 over 24 hours. This work exhibits an effective and durable active particle-active support system enhancing the performance of the NO3RR, enabling industrially relevant current densities and near 100% selectivity.

2.
ACS Omega ; 9(5): 5761-5771, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38343941

ABSTRACT

Catalpol (CA), a compound derived from the roots of Rehmannia glutinosa, is recognized for its anti-oxidative and anti-inflammatory properties. The current study aimed to evaluate the impact of CA on the osseointegration of titanium implants (TIs) in the context of type 2 diabetes and elucidate the underlying pharmacological mechanisms. MC3T3-E1 cells were incubated on the surface of titanium plates and exposed to various media for investigating osteoblast behaviors, as follows: regular medium, medium of high glucose and high lipid (HGHL) that simulates diabetic conditions, HGHL + CA medium, or HGHL + CA + LY294002 (an inhibitor of phosphoinositide 3-kinase or PI3K) medium. TIs were also surgically implanted into the femoral condyle defects in normal mice and mouse models of type 2 diabetes mellitus (T2DM). HGHL-induced oxidative stress was found to cause osteoblast dysfunction, accompanied by the inactivation of AKT/GSK3ß/FYN pathway-mediated NRF2 signaling. However, CA administration effectively mitigated HGHL-induced oxidative stress and reactivated AKT/GSK3ß/FYN/NRF2 signaling, resulting in the reversal of HGHL-induced dysfunctions in MC3T3-E1 cells, as evidenced by enhanced osteoblast adhesion, proliferation, and differentiation, as well as reduced apoptotic injury. In addition, the positive effects of CA were confirmed in vivo by enhanced osseointegration of TIs observed in mouse models of T2DM using microcomputed tomography and histological analyses. However, the pro-osteogenic effects of CA were almost completely nullified by the addition of LY294002. These findings demonstrated for the first time that CA administration ameliorates the impairment in osseointegration of TIs under conditions of T2DM via AKT/GSK3ß/FYN pathway-mediated NRF2 activation. Given its antioxidative and pro-osteogenic properties, CA administration holds promise as a reliable therapeutic strategy in the future for implant restoration in patients with T2DM.

3.
Environ Geochem Health ; 45(7): 5467-5480, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37099043

ABSTRACT

Antimony (Sb) and arsenic (As) co-contamination occurs in Sb smelting areas and is harmful to the surrounding ecological environment. The purpose of this study is to explore the spatial distribution characteristics of Sb and As in abandoned Sb smelting area and carry out risk assessments. Soil samples were collected from the smelting area profile and background points, and groundwater samples were also collected. Samples from two geological background sections were collected to understand the geological background characteristics of Sb and As. The spatial distribution was drawn via the inverse distance weighted interpolation method. The hazard assessment was carried out by the geo-accumulation index and potential ecological hazard methods. The results showed that special high geological background value of Sb and As in study area. Sb and As co-contamination is one of the characters in soil. And the contents of Sb and As decrease as depth increases, reflecting the weak migration capacity. The spatial distribution of Sb and As is affected by slag distribution and rainfall leaching. The Sb content in groundwater was higher in the wet and normal seasons than in the dry season, slag leaching may be one of the elements. The potential ecological hazards of Sb and As are high and considerable, respectively. In abandoned smelting area with high geological background values, it is necessary to focus on the pollution abatement and protection of ecological health.


Subject(s)
Arsenic , Soil Pollutants , Antimony/analysis , Arsenic/analysis , Soil Pollutants/analysis , Environmental Monitoring/methods , Soil , China , Risk Assessment
4.
J Mol Histol ; 49(2): 123-131, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29356923

ABSTRACT

Orthodontic tooth movement (OTM) is a periodontal tissue remodeling and regeneration process that is caused by bio-mechanical stimulation. This mechanical-chemical transduction process involves a variety of biological factors and signaling pathways. It has been shown that the Hippo-YAP/TAZ signaling pathway plays a pivotal role in the mechanical-chemical signal transduction process. Moreover, YAP and TAZ proteins interact with RUNX family proteins via different mechanisms. To explore the regulation of the Hippo signaling pathway during periodontal tissue remodeling, we examined the upper first molar OTM model in rats. We examined YAP, TAZ and RUNX2 expression at 12 hours, 24 hours, 2 days (2d), 4 days, 7 days (7d) and 14 days (14d) after force application. Haemotoxylin and eosin staining, immunohistochemical staining and western blot analysis were used to examine the expression level and localization of these proteins. We found that YAP, TAZ and RUNX2 expression started increasing at 2d, YAP and TAZ expression was proportional to the orthodontic force applied until peaking at 7d, and at 14d the expression started to decrease. YAP and TAZ were observed in osteocytes, bone matrix and periodontal ligament cells during OTM. Furthermore, using double labeling immunofluorescence staining, we found that the increase in TAZ expression was associated with RUNX2 expression, however, YAP and RUNX2 showed different expression patterns. These results suggest that the Hippo-YAP/TAZ signaling pathway participates in periodontal tissue remodeling through various mechanisms; TAZ may adjust bone tissue remodeling through RUNX2 during OTM, while YAP may regulate periodontal cell proliferation and differentiation.


Subject(s)
Apoptosis Regulatory Proteins/analysis , Core Binding Factor Alpha 1 Subunit/analysis , Tooth Movement Techniques , Transcription Factors/analysis , Acyltransferases , Animals , Apoptosis Regulatory Proteins/metabolism , Core Binding Factor Alpha 1 Subunit/metabolism , Protein Serine-Threonine Kinases/metabolism , Rats , Signal Transduction , Transcription Factors/metabolism , YAP-Signaling Proteins
5.
J Mol Histol ; 48(4): 311-319, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28647773

ABSTRACT

Collagen triple helix repeat containing 1 (CTHRC1) is associated with bone metabolism. Alveolar bone has an ability to rapidly remodel itself to adapt its biomechanical environment and function. However, whether CTHRC1 is expressed in alveolar bone tissue and the role of CTHRC1 in alveolar bone remodeling remain unclear. We used orthodontic tooth movement (OTM) rat model to study the effects of CHTRC1 in alveolar bone remodeling in vivo. We found that CTHRC1 was expressed in normal physiological condition of osteocytes, bone matrix, and periodontal ligament cells in rat. During the OTM, the expression of CTHRC1, Runx2 and TAZ were increased. We further studied the effects of CTHRC1 on osteogenic differentiation of human periodontal ligament stem cells in vitro. CTHRC1 can positively regulate the expression of TAZ and osteogenic differentiation markers like Col1, ALP, Runx2 and OCN. Overexpression of CHTRC1 increased osteogenic differentiation of PDLSCs, which could be abolished by TAZ siRNA. Our results suggest that CTHRC1 plays an important role in alveolar bone remodeling and osteogenic differentiation of PDLSCs.


Subject(s)
Cell Differentiation , Glycoproteins/physiology , Osteogenesis , Periodontal Ligament/cytology , Stem Cells/cytology , Transcription Factors/physiology , Acyltransferases , Alveolar Process , Animals , Bone Remodeling , Gene Expression Regulation , Humans , Rats , Tooth Movement Techniques
6.
Intractable Rare Dis Res ; 3(3): 87-90, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25364649

ABSTRACT

Noninvasive prenatal testing (NIPT) provides an innovative method to detect genetic conditions in fetuses using a maternal blood sample, thus avoiding the risk of miscarriage associated with traditional invasive procedures. Since 80% of rare diseases are genetic diseases, NIPT has the potential to detect rare genetic diseases early on and it has been used in many countries and regions. Since China has the world's largest population of patients with rare diseases, NIPT has been implemented in China since 2010. However, the regulations governing NIPT in China are weak and NIPT oversight and research are still lacking. Strict registration is needed to ensure the quality of NIPT, additional certification can help a developer/manufacturer of an NIPT test to compile clinical data and to improve innovation, and academic societies can provide committee opinions that are suited to the current situation in China. These efforts may improve regulations governing NIPT and NIPT oversight and research in China. With these improvements, NIPT may offer promise in terms of the early detection of rare diseases.

7.
PLoS One ; 9(6): e98981, 2014.
Article in English | MEDLINE | ID: mdl-24901319

ABSTRACT

GOAL: To investigate the effect of luteolin on methamphetamine (MA)-induced behavioral sensitization and mitogen-activated protein kinase (MAPK) signal transduction pathway activation in mice. METHODS: Mice received a single dose of MA to induce hyperactivity or repeated intermittent intraperitoneal injections of MA to establish an MA-induced behavioral sensitization mouse model. The effect of luteolin on the development and expression of MA-induced hyperactivity and behavioral sensitization was examined. The expression and activity of ΔFosB and the levels of phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2), phosphorylated c-Jun N-terminal kinase (pJNK), and phosphorylated p38 mitogen-activated protein kinase (pp38) in the caudate putamen (CPu) were measured by western blot. RESULTS: Luteolin significantly decreased hyperactivity as well as the development and expression of MA-induced behavioral sensitization in mice. ΔFosB, pERK1/2, and pJNK levels in the CPu were higher in MA-treated mice than in control mice, whereas the pp38 level did not change. Injection of luteolin inhibited the MA-induced increase in ΔFosB, pERK1/2, and pJNK levels, but did not affect the pp38 level. CONCLUSIONS: Luteolin inhibits MA-induced hyperactivity and behavioral sensitization in mice through the ERK1/2/ΔFosB pathway. Furthermore, the JNK signaling pathway might be involved in MA-induced neurodegeneration in the CPu, and luteolin inhibits this process.


Subject(s)
Luteolin/pharmacology , Methamphetamine/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Putamen/metabolism , Signal Transduction/drug effects , Animals , JNK Mitogen-Activated Protein Kinases/metabolism , Male , Mice , Mice, Inbred C57BL , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Motor Activity/drug effects , Phosphorylation/drug effects , Proto-Oncogene Proteins c-fos/genetics , Proto-Oncogene Proteins c-fos/metabolism , Putamen/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
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