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1.
Langmuir ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950193

RESUMO

The key to enhancing water electrolysis efficiency lies in selecting highly efficient catalysts. Currently, high-entropy alloys (HEAs) are utilized in electrocatalysis applications owing to their diverse elemental composition, disordered elemental distribution, and the high solubility of each element, endowing them with excellent catalytic performance. The experiments were conducted using isoatomic FeNiCrMo HEA as a precursor, with a high-activity three-dimensional nanoporous structure rapidly synthesized via electrochemical one-step dealloying in a choline chloride-thiourea (ChCl-TU) deep eutectic solvent (DES). The results indicate that the dealloyed Fe20Co20Ni20Cr20Mo20 HEA mainly consists of two phases: face-centered cubic and σ phases. The imbalance in the distribution of elements in these two phases leads to quite different corrosion speeds with the FCC phase being preferentially corroded. Furthermore, synergistic electron coupling between surface atoms in the three-dimensional nanoporous structure strengthens the behavior of the oxygen evolution reaction (OER). At a current density of 40 mA cm-2, the overpotential after dealloying decreased to 370 mV, demonstrating excellent stability. The technique demonstrated in this work provides a novel approach to improve the catalytic activity of OER.

2.
Phys Chem Chem Phys ; 26(17): 12928-12938, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38456623

RESUMO

Copper has been shown to be an important substrate for the growth of borophenes. Copper-boron binary clusters are ideal platforms to study the interactions between copper and boron, which may provide insight about the underlying growth mechanisms of borophene on copper substrates. Here we report a joint photoelectron spectroscopy and theoretical study on two copper-doped boron clusters, CuB7- and CuB8-. Well resolved photoelectron spectra are obtained for the two clusters at different wavelengths and are used to understand the structures and bonding properties of the two CuBn- clusters. We find that CuB8- is a highly stable borozene complex, which possesses a half-sandwich structure with a Cu+ species interacting with the doubly aromatic η8-B82- borozene. The CuB7- cluster is found to consist of a terminal copper atom bonded to a double-chain B7 motif, but it has a low-lying isomer composed of a half-sandwich structure with a Cu+ species interacting with an open-shell η7-B72- borozene. Both ionic and covalent interactions are found to be possible in the binary Cu-B clusters, resulting in different structures.

3.
Phys Chem Chem Phys ; 26(6): 5356-5367, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38269413

RESUMO

Boron has been found to be able to form multiple bonds with lead. To probe Pb-B bonding, here we report an investigation of three Pb-doped boron clusters, PbB2-, PbB3O-, and PbB4O2-, which are produced by a laser ablation cluster source and characterized by photoelectron spectroscopy and ab initio calculations. The most stable structures of PbB2-, PbB3O-, and PbB4O2- are found to follow the formula, [PbB2(BO)n]- (n = 0-2), with zero, one, and two boronyl ligands coordinated to a triangular and aromatic PbB2 core, respectively. The PbB2- cluster contains a BB double bond and two Pb-B single bonds. The coordination of BO is observed to weaken Pb-B bonding but strengthen the BB bond in [PbB2(BO)n]- (n = 1, 2). The anionic [PbB2(BO)2]- and its corresponding neutral closed-shell [PbB2(BO)2] contain a BB triple bond. A low-lying Y-shaped isomer is also observed for PbB4O2-, consisting of a central sp2 hybridized B atom bonded to two boronyl ligands and a PbB unit.

4.
J Biochem Mol Toxicol ; 38(1): e23544, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37815058

RESUMO

To investigate the key molecular mechanisms of palmatine for the treatment of neuroinflammation through modulation of a pathway using molecular docking, molecular dynamics (MD) simulation combined with network pharmacology, and animal experiments. Five alkaloid components were obtained from the traditional Chinese medicine Huangteng through literature mining. Molecular docking and MD simulation with acetylcholinesterase were used to screen palmatine. At the animal level, mice were injected with LPS intracerebrally to cause a neuroinflammatory model, and the Morris water maze experiment was performed to examine the learning memory of mice. Anxiety levels were tested using the autonomous activity behavior experiment with the open field and elevated behavior experiments. HE staining and Niss staining were performed on brain tissue sections to observe morphological lesions and apoptosis; serum was examined for inflammatory factors TNF-α, IL-6, and IL-1ß; Western blot was performed to detect the protein expression. The expression of PI3K/AKT/NFkB signaling pathway-related proteins was examined by Western blot. The results of network pharmacology showed that the screening of palmatine activation containing the PI3K/Akt/NFkB signaling pathway exerts antineuroinflammatory effects. Results from behavioral experiments showed that Pal enhanced learning memory in model mice, improved anxiety behavior, and significantly improved brain damage caused by neuroinflammation. The results of HE staining and Niss staining of brain tissue sections showed that palmatine could alleviate morphological lesions and nucleus damage in brain tissue. Palmatine improved the levels of serum inflammatory factors TNF-α, IL-6, and IL-1ß. SOD, MDA, CAT, ACH, and ACHE in the hippocampus were improved. Western blot results showed that palmatine administration ameliorated LPS-induced neuroinflammation through the PI3K/Akt/NFkB pathway.


Assuntos
Alcaloides de Berberina , NF-kappa B , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Lipopolissacarídeos/toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Doenças Neuroinflamatórias , Interleucina-6 , Acetilcolinesterase , Simulação de Acoplamento Molecular
5.
J Phys Chem A ; 128(18): 3564-3570, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38676655

RESUMO

Spontaneous symmetry-breaking is common in chemical and physical systems. Here, we show that by adding an electron to the C7v PbB8 cluster, which consists of a planar B8 disk with the Pb atom situated along the C7 axis, the Pb atom spontaneously moves to the off-axis position in the PbB8- anion. Photoelectron spectroscopy of PbB8- reveals a broad ground-state transition and a large energy gap, suggesting a highly stable closed-shell PbB8 borozene complex and a significant geometry change upon electron detachment. Quantum chemistry calculations indicate that the lowest unoccupied molecular orbital of the C7v PbB8 cluster is a degenerate π orbital mainly consisting of the Pb 6px and 6py atomic orbitals. Occupation of one of the 6p orbitals spontaneously break the C7v symmetry in the anion due to the Jahn-Teller effect. The large amplitude of the position change of Pb in PbB8- relative to PbB8 is surprising owing to bonding interactions between the Pb 6p orbital with the π orbital of the B8 borozene.

6.
BMC Geriatr ; 24(1): 331, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605326

RESUMO

BACKGROUND: Motor cognitive risk syndrome (MCR) represents a critical pre-dementia and disability state characterized by a combination of objectively measured slow walking speed and subjective memory complaints (SMCs). This study aims to identify risk factors for MCR and investigate the relationship between plasma levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and MCR among Chinese community-dwelling elderly populations. METHODS: A total of 1312 participants were involved in this study based on the data of the Rugao Longevity and Aging Study (RuLAS). The MCR was characterized by SMCs and slow walking speed. The SCCs were defined as a positive answer to the question 'Do you feel you have more problems with memory than most?' in a 15-item Geriatric Depression Scale. Slow walking speed was determined by one standard deviation or more below the mean value of the patient's age and gender group. The plasma of 8-OHdG were measured by a technician in the biochemistry laboratory of the Rugao People's Hospital during the morning of the survey. RESULTS: The prevalence of MCR was found to be 7.9%. After adjusting for covariates, significant associations with MCR were observed in older age (OR 1.057; p = 0.018), history of cerebrovascular disease (OR 2.155; p = 0.010), and elevated 8-OHdG levels (OR 1.007; p = 0.003). CONCLUSIONS: This study indicated the elevated plasma 8-OHdG is significantly associated with increased MCR risk in the elderly, suggesting its potential as a biomarker for early detection and intervention in MCR. This finding underscores the importance of monitoring oxidative DNA damage markers in predicting cognitive and motor function declines, offering new avenues for research and preventive strategies in aging populations.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , População do Leste Asiático , Humanos , Idoso , Transtornos Cognitivos/diagnóstico , Estudos Transversais , 8-Hidroxi-2'-Desoxiguanosina , Longevidade , Envelhecimento/psicologia , Fatores de Risco , Cognição , Disfunção Cognitiva/epidemiologia
7.
Korean J Physiol Pharmacol ; 28(4): 361-377, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38926843

RESUMO

The dried rattan stem of the Fibraurea Recisa Pierre plant contains the active ingredient known as fibrauretine (FN). Although it greatly affects Alzheimer's disease (AD), the mechanism of their effects still remains unclear. Proteomics and transcriptomics analysis methods were used in this study to determine the mechanism of FN in the treatment of AD. AD model is used through bilateral hippocampal injection of Aß1-40. After successful modeling, FN was given for 30 days. The results showed that FN could improve the cognitive dysfunction of AD model rats, reduce the expression of Aß and P-Tau, increase the content of acetylcholine and reduce the activity of acetylcholinesterase. The Kyoto Encyclopedia of Genes and Genomes enriched differentially expressed genes and proteins are involved in signaling pathways including metabolic pathway, AD, pathway in cancer, PI3K-AKT signaling pathway, and cAMP signaling pathway. Transcriptomics and proteomics sequencing resulted in 19 differentially expressed genes and proteins. Finally, in contrast to the model group, after FN treatment, the protein expressions and genes associated with the PI3K-AKT pathway were significantly improved in RT-qPCR and Western blot and assays. This is consistent with the findings of transcriptomic and proteomic analyses. Our study found that, FN may improve some symptoms of AD model rats through PI3K-AKT signaling pathway.

8.
Int J Neuropsychopharmacol ; 26(10): 680-691, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37603290

RESUMO

BACKGROUND: Although depression has been a serious neuropsychiatric disorder worldwide, current antidepressants used in clinical practice have various weaknesses, including delayed onset and low rates of efficacy. Recently, the development of new antidepressants from natural herbal medicine has become one of the important research hotspots. Cucurbitacin B is a natural compound widely distributed in the Cucurbitaceae and Cruciferae families and has many pharmacological activities. The present study aimed to investigate whether cucurbitacin B possess antidepressant-like effects in mice. METHODS: The antidepressant-like effects of cucurbitacin B on mice behaviors were explored using the forced swim test, tail suspension test, open field test, sucrose preference test, and a chronic unpredictable mild stress model of depression together. Then, western blotting and immunofluorescence were used to examine the effects of cucurbitacin B on the brain-derived neurotrophic factor (BDNF)-tyrosine kinase B (TrkB) signaling cascade and neurogenesis in the hippocampus of mice. Furthermore, BDNF-short hairpin RNA, K252a, and p-chlorophenylalanine methyl ester were adopted together to determine the antidepressant mechanism of cucurbitacin B. RESULTS: It was found that administration of cucurbitacin B indeed produced notable antidepressant-like effects in mice, which were accompanied with significant promotion in both the hippocampal BDNF-TrkB pathway and neurogenesis. The antidepressant mechanism of cucurbitacin B involves the hippocampal BDNF-TrkB system but not the serotonin system. CONCLUSIONS: Cucurbitacin B has the potential to be a novel antidepressant candidate.


Assuntos
Antidepressivos , Fator Neurotrófico Derivado do Encéfalo , Depressão , Animais , Humanos , Camundongos , Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/tratamento farmacológico , Depressão/metabolismo , Modelos Animais de Doenças , Hipocampo , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo
9.
Mol Psychiatry ; 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36434056

RESUMO

Elucidating the molecular mechanism underlying the hyperactivity of the hypothalamic-pituitary-adrenal axis during chronic stress is critical for understanding depression and treating depression. The secretion of corticotropin-releasing hormone (CRH) from neurons in the paraventricular nucleus (PVN) of the hypothalamus is controlled by salt-inducible kinases (SIKs) and CREB-regulated transcription co-activators (CRTCs). We hypothesised that the SIK-CRTC system in the PVN might contribute to the pathogenesis of depression. Thus, the present study employed chronic social defeat stress (CSDS) and chronic unpredictable mild stress (CUMS) models of depression, various behavioural tests, virus-mediated gene transfer, enzyme-linked immunosorbent assay, western blotting, co-immunoprecipitation, quantitative real-time reverse transcription polymerase chain reaction, and immunofluorescence to investigate this connection. Our results revealed that both CSDS and CUMS induced significant changes in SIK1-CRTC1 signalling in PVN neurons. Both genetic knockdown of SIK1 and genetic overexpression of CRTC1 in the PVN simulated chronic stress, producing a depression-like phenotype in naive mice, and the CRTC1-CREB-CRH pathway mediates the pro-depressant actions induced by SIK1 knockdown in the PVN. In contrast, both genetic overexpression of SIK1 and genetic knockdown of CRTC1 in the PVN protected against CSDS and CUMS, leading to antidepressant-like effects in mice. Moreover, stereotactic infusion of TAT-SIK1 into the PVN also produced beneficial effects against chronic stress. Furthermore, the SIK1-CRTC1 system in the PVN played a role in the antidepressant actions of fluoxetine, paroxetine, venlafaxine, and duloxetine. Collectively, SIK1 and CRTC1 in PVN neurons are closely involved in depression neurobiology, and they could be viable targets for novel antidepressants.

10.
Crit Care ; 27(1): 275, 2023 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-37424026

RESUMO

BACKGROUND: The oXiris is a novel filter for continuous renal replacement therapy (CRRT) featuring an adsorption coating to adsorb endotoxins and remove inflammatory mediators. Given that no consensus has been reached on its potential benefits in treating sepsis, a meta-analysis was conducted to assess its impact on the clinical outcomes of this patient population. METHODS: Eleven databases were retrieved to find relevant observational studies and randomized controlled trials. The Newcastle-Ottawa Scale and the Cochrane Risk of Bias Tool were used to assess the quality of the included studies. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) process was employed to assess the certainty of evidence. The 28-day mortality was the primary outcome. Secondary outcomes were 7-, 14-, and 90-day mortality, length of intensive care unit (ICU) and hospital stay, ICU and hospital mortality, norepinephrine (NE) dose, interleukin-6 (IL-6) and lactate levels, and Sequential Organ Failure Assessment (SOFA) score. RESULTS: The meta-analysis, pooling data from 14 studies, involving 695 patients, showed significant reductions in 28-day mortality [odds ratio (OR) 0.53; 95% confidence interval (CI) 0.36-0.77, p = 0.001] and length of ICU stay [weighted mean difference (WMD) - 1.91; 95% CI - 2.56 to - 1.26, p < 0.001)] in patients with sepsis using the oXiris filter compared to other filters. Besides, the SOFA score, NE dose, IL-6 and lactate levels, and 7- and 14-day mortalities were lower in the oXiris group. However, the 90-day mortality, ICU and hospital mortality, and length of hospital stay were comparable. The quality assessment of the ten observational studies indicated intermediate to high quality (average Newcastle-Ottawa score: 7.8). However, all four randomized controlled trials (RCTs) had an unclear risk of bias. The evidence for all outcomes had a low or very low level of certainty because the original study design was mainly observational studies and the RCTs included had an unclear risk of bias and a small sample size. CONCLUSION: The treatment with the oXiris filter during CRRT in sepsis patients may be associated with lower 28-, 7-, and 14-day mortalities, lactate levels, SOFA score, NE dose, and shorter length of ICU stay. However, due to the low or very low quality of evidence, the effectiveness of oXiris filters was still uncertain. Besides, no significant difference was observed for the 90-day mortality, ICU and hospital mortality, and length of hospital stay.


Assuntos
Terapia de Substituição Renal Contínua , Sepse , Humanos , Interleucina-6 , Adsorção , Lactatos/uso terapêutico
11.
J Biochem Mol Toxicol ; 37(1): e23225, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36169195

RESUMO

Depression is one of the most common neuropsychiatric disorders that is characterized by low mood, lack of motivation, slow thinking, and recurrent suicidal thoughts. The mechanism of action of palmatine in depression has been rarely reported and remains unclear. The present study examined the neuroprotective effects of palmatine on lipopolysaccharide (LPS)-induced oxidative stress, apoptosis, and depression-like behavior. In this study, cell apoptosis was evaluated by CCK-8, flow cytometry, and Hoechst 33258 staining in LPS-induced HT-22 cells. Meanwhile, reactive oxygen species (ROS) and mitochondrial membrane potential were detected in vitro. In vivo, we investigated depressive-like behaviors in mice by an open field test (OFT) and elevated plus-maze test (EPM). Additionally, the levels of superoxide dismutases (SOD), TNF-α, IL-1ß, and IL-6 were detected by enzyme-linked immunosorbent assay. The hematoxylin-eosin staining and TUNEL staining were used to evaluate the pathology of the hippocampus. The expression of Nrf2/HO-1 and BAX/Bcl-2 pathways in the hippocampus were assessed by Western blot analysis. Palmatine could significantly reduce apoptosis and ROS levels, and improve mitochondrial damage. Moreover, palmatine significantly improves movement time and central square crossing time in OFT, and improves open arms and movement time in EMP. And the levels of SOD, TNF-α, IL-1ß, and IL-6 were significantly decreased after palmatine treatment. More importantly, palmatine improved neuronal apoptosis in the hippocampus, and depression through BAX/Bcl-2 and Nrf2/HO-1 signaling pathways. We provide evidence that palmatine further alleviates the depressive-like behavior of LPS-induced by improving apoptosis and oxidative stress.


Assuntos
Depressão , Lipopolissacarídeos , Camundongos , Animais , Lipopolissacarídeos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Depressão/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Estresse Oxidativo , Apoptose , Superóxido Dismutase/metabolismo
12.
J Biochem Mol Toxicol ; 37(5): e23319, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36811218

RESUMO

Organophosphorus pesticides (OPs) have long been used extensively on agricultural land and can lead to significant improvements in crop yields. Due to occupational exposure, humans are exposed to pesticides through dermal contact, inhalation, and ingestion. The effects of OPs on the organism are currently studied for their effects on livers, kidneys, hearts, blood indicators, neurotoxicity, and teratogenic, carcinogenic, and mutagenic effects, while studies in the direction of brain tissue damage have not been reported in detail. Previous reports have confirmed that ginsenoside Rg1 is a prominent and representative tetracyclic triterpenoid derivative rich in ginseng and has good neuroprotective activity. Considering that, the aim of this study was to establish a mouse model of brain tissue injury by using the OP-type pesticide chlorpyrifos (CPF) and to explore the therapeutic effects and possible molecular mechanisms of Rg1. Mice in the experimental group were pre-protected with Rg1 by gavage for 1 week, and brain tissue damage was induced using CPF (5 mg/kg for 1 week) to assess the effect of Rg1 (80 and 160 mg/kg for 3 weeks) in alleviating brain damage. Morris water maze and histopathological analysis were performed to assess cognitive function and pathological changes in the mouse brain, respectively. Protein expression levels of Bax, Bcl-2, Caspase-3, Cl-Cas-3, Caspase-9, Cl-Cas-9, phosphoinositide 3-kinase (PI3K), phosphorylated-PI3K, protein kinase B (AKT), and phosphorylated-AKT were quantified by protein blotting analysis. Rg1 obviously restored CPF-induced oxidative stress damage in mouse brain tissue, increased the levels of antioxidant parameters (total superoxide dismutase, total antioxidative capacity, and glutathione) in the brain, and significantly reduced the overexpression of apoptosis-related proteins induced by CPF. At the same time, Rg1 also markedly attenuated the histopathological changes in the brain induced by CPF exposure. Mechanistically, Rg1 could effectively activate the phosphorylation of PI3K/AKT. Furthermore, molecular docking studies revealed a stronger binding capacity between Rg1 and PI3K. Rg1 attenuated neurobehavioural alterations and reduced lipid peroxidation in the mouse brain to a great extent. Apart from that, Rg1 administration improved brain histopathology in CPF-induced rats. All results suggest that ginsenoside Rg1 has potential antioxidant effects on CPF-induced oxidative brain injury, and it is evident that Rg1 could be used as a promising therapeutic strategy for the study of brain injury from OP poisoning.


Assuntos
Lesões Encefálicas , Clorpirifos , Praguicidas , Animais , Camundongos , Antioxidantes , Lesões Encefálicas/induzido quimicamente , Lesões Encefálicas/tratamento farmacológico , Simulação de Acoplamento Molecular , Compostos Organofosforados , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt
13.
J Biochem Mol Toxicol ; 37(6): e23345, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37050869

RESUMO

The role of polysaccharide components in the immune system, especially immunomodulatory effects, has received increasing attention. In this context, in this study, network pharmacology was adopted to explore the hypothesis of a multitarget mechanism for immune modulation by Chrysalis polysaccharides. A total of 174 common targets were screened by network pharmacology, with the main ones being TNF, MAPK3, CASP3, VEGFA, and STAT3, mostly enriched in the Toll pathway. The molecular docking results showed that the polysaccharide fraction of Chrysalis binds well to TNF proteins. Besides, in vitro cellular assays were performed to verify the ability of Chrysalis polysaccharides to regulate macrophage polarization and to screen for macrophage surface receptors. Furthermore, in vivo experiments were conducted to prove the activation of TLR4 and TNF-α protein expression in mice by Chrysalis polysaccharide.


Assuntos
Cordyceps , Medicamentos de Ervas Chinesas , Camundongos , Animais , Fator de Necrose Tumoral alfa/metabolismo , Simulação de Acoplamento Molecular , Receptor 4 Toll-Like , Farmacologia em Rede , Polissacarídeos/farmacologia
14.
J Phys Chem A ; 127(22): 4888-4896, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37235389

RESUMO

Copper has been found to be able to mediate the formation of bilayer borophenes. Copper-boron binary clusters are ideal model systems to probe the copper-boron interactions, which are essential to understand the growth mechanisms of borophenes on copper substrates. Here, we report a joint photoelectron spectroscopy and theoretical study on two di-copper-doped boron clusters: Cu2B3- and Cu2B4-. Well-resolved photoelectron spectra are obtained, revealing the presence of a low-lying isomer in both cases. Theoretical calculations show that the global minimum of Cu2B3- (C2v, 1A1) contains a doubly aromatic B3- unit weakly interacting with a Cu2 dimer, while the low-lying isomer (C2v, 1A1) consists of a B3 triangle with the two Cu atoms covalently bonded to two B atoms at two vertexes. The global minimum of Cu2B4- (D2h, 2Ag) is found to consist of a rhombus B4 unit covalently bonded to the two Cu atoms at two opposite vertexes, whereas in the low-lying isomer (Cs, 2A'), one of the two Cu atoms is bonded to two B atoms.

15.
J Chem Phys ; 159(11)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37712786

RESUMO

We report a study on the electronic structure and chemical bonding of the BiB molecule using high-resolution photoelectron imaging of cryogenically cooled BiB- anion. By eliminating all the vibrational hot bands, we can resolve the complicated detachment transitions due to the open-shell nature of BiB and the strong spin-orbit coupling. The electron affinity of BiB is measured to be 2.010(1) eV. The ground state of BiB- is determined to be 2Π(3/2) with a σ2π3 valence electron configuration, while the ground state of BiB is found to be 3Σ-(0+) with a σ2π2 electron configuration. Eight low-lying spin-orbit excited states [3Σ-(1), 1Δ(2), 1Σ+(0+), 3Π(2), 3Π(1), 1Π(1)], including two forbidden transitions, [3Π(0-) and 3Π(0+)], are observed for BiB as a result of electron detachment from the σ and π orbitals of BiB-. The angular distribution information from the photoelectron imaging is found to be critical to distinguish detachment transitions from the σ or π orbital for the spectral assignment. This study provides a wealth of information about the low-lying electronic states and spin-orbit coupling of BiB, demonstrating the importance of cryogenic cooling for obtaining well-resolved photoelectron spectra for size-selected clusters produced from a laser vaporization cluster source.

16.
J Adv Nurs ; 79(5): 1926-1938, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35975332

RESUMO

AIMS: To identify the different classes of total knee arthroplasty patients according to the heterogenous trajectories of psychological resilience and investigate the predictors for different patterns of resilience. DESIGN: A prospective cohort study. METHODS: A total of 210 patients with total knee arthroplasty from March to December 2021 were included. Baseline assessment (T0) data were collected before surgery and included demographic, biological (clinical characteristics), psychological (psychological resilience, self-efficacy, psychological distress, hope, medical coping mode) and social (social support) factors. Resilience measurements were repeated at 3 days after surgery (T1), the date of discharge (T2), and 1 month (T3) and 3 months (T4) after discharge. Latent growth mixture modelling was employed to define different resilience trajectories. Predictors of class membership were identified using multinomial logistic regression. RESULTS: Data from 198 patients were analysed. Three latent classes were identified with similar patterns in different intercepts, showing a significant decrease in resilience from admission (T0) to 3 days after surgery (T1) followed by an increase from T1 to T4. The three trajectories of psychological resilience were named the stable-resilience class (65.66%), high-resilience class (17.68%), and low-resilience class (16.66%). Multinomial logistic regression showed that compared with the stable-resilience class, the high-resilience class was predicted by having a higher level of hope, having higher education, living in urban areas and having more children, while the low-resilience class was predicted by having lower levels of self-efficacy and hope, living in semirural areas, and having more children. CONCLUSIONS: The three trajectories indicated that surgery was the major stressor influencing patients' psychological resilience and that patients in the low-resilience class needed to be intervened. IMPACT: Predictors of patients in different classes provide evidence for the identification of vulnerable populations and lay a foundation for future research contributing to the development of targeted interventions for improving patients' psychological resilience. No patient or public contribution but the time points of investigation were decided based on our interviews with 12 total knee arthroplasty patients.


Assuntos
Artroplastia do Joelho , Resiliência Psicológica , Criança , Humanos , Estudos Longitudinais , Estudos Prospectivos , Adaptação Psicológica
17.
Int J Mol Sci ; 24(21)2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37958950

RESUMO

In recent years, the phenomenon of acute poisoning and organ damage caused by organophosphorus pesticides (OPs) has been a frequent occurrence. Chlorpyrifos (CPF) is one of the most widely used organophosphorus pesticides. The main active components of ginseng stems and leaves are total ginseng stem-and-leaf saponins (GSLSs), which have various biological effects, including anti-inflammatory, antioxidant and anti-tumor activities. We speculate that these could have great potential in the treatment of severe diseases and the relief of organophosphorus-pesticide-induced side effects; however, their mechanism of action is still unknown. At present, our work aims to evaluate the effects of GSLSs on the antioxidation of CPF in vivo and in vitro and their potential pharmacological mechanisms. Mice treated with CPF (5 mg/kg) showed severe intestinal mucosal injury, an elevated diamine oxidase (DAO) index, the decreased expression of occlusive protein-1 (ZO-1) and occlusive protein, an impaired intestinal mucosal oxidation system and intestinal villi relaxation. In addition, chlorpyrifos exposure significantly increased the contents of the inflammatory factor TNF-α and the oxidative-stress-related indicators superoxide dismutase (SOD), catalase (CAT), glutathione SH (GSH), glutathione peroxidase (GSH-PX), reactive oxygen species (ROS) and total antioxidant capacity (T-AOC); elevated the level of lipid peroxide malondialdehyde (MDA); reversed the expression of Bax and caspase; and activated NF-κB-related proteins. Interestingly, GSLS supplementation at doses of 100 and 200 mg/kg significantly reversed these changes after treatment. Similar results were observed in cultured RAW264.7 cells. Using flow cytometry, Hoechst staining showed that GSLSs (30 µg/mL, 60 µg/mL) could improve the cell injury and apoptosis caused by CPF and reduce the accumulation of ROS in cells. In conclusion, GSLSs play a protective role against CPF-induced enterotoxicity by inhibiting NF-κB-mediated apoptosis and alleviating oxidative stress and inflammation.


Assuntos
Clorpirifos , Panax , Praguicidas , Saponinas , Camundongos , Animais , Clorpirifos/toxicidade , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NF-kappa B/metabolismo , Panax/metabolismo , Saponinas/farmacologia , Compostos Organofosforados/farmacologia , Praguicidas/farmacologia , Estresse Oxidativo , Glutationa/metabolismo , Apoptose , Folhas de Planta/metabolismo
18.
Molecules ; 28(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38067664

RESUMO

Neurological-related disorders are diseases that affect the body's neurons or peripheral nerve tissue, such as Parkinson's disease (PD) and Alzheimer's disease (AD). The development of neurological disorders can cause serious harm to the quality of life and functioning of the patient. The use of traditional therapeutic agents such as dopamine-promoting drugs, anticholinergic drugs, cholinesterase inhibitors, and NMDA receptor antagonists is often accompanied by a series of side effects such as drug resistance, cardiac arrhythmia, liver function abnormalities, and blurred vision. Therefore, there is an urgent need to find a therapeutic drug with a high safety profile and few side effects. Herbal medicines are rich in active ingredients that are natural macromolecules. Ginsenoside is the main active ingredient of ginseng, which has a variety of pharmacological effects and is considered to have potential value in the treatment of human diseases. Modern pharmacological studies have shown that ginsenosides Rg2 and Rh1 have strong pharmacological activities in the nervous system, with protective effects on nerve cells, improved resistance to neuronal injury, modulation of neural activity, resistance to cerebral ischemia/reperfusion injury, improvement of brain damage after eclampsia hemorrhage, improvement of memory and cognitive deficits, treatment of AD and vascular dementia, alleviation of anxiety, pain, and inhibition of ionic-like behavior. In this article, we searched the pharmacological research literature of Rg2 and Rh1 in the field of neurological diseases, summarized the latest research progress of the two ginsenosides, and reviewed the pharmacological effects and mechanisms of Rg2 and Rh1, which provided a new way of thinking for the research of the active ingredients in ginseng anti-neurological diseases and the development of new drugs.


Assuntos
Ginsenosídeos , Panax , Humanos , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Qualidade de Vida , Sistema Nervoso
19.
Molecules ; 29(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38202727

RESUMO

Polysaccharides are the main effective components of Cynomorium songaricum's stem that perform biological activities and have positive impacts on immune enhancement. In this study, the polysaccharide CSP-III of Cynomorium songaricum's stem was isolated using a DEAE-52 cellulose column through Sephadex G-100 gel column chromatography. Upon analysis, the monosaccharide composition of CSP-III included Mannose (Man), Glucuronic acid (GlcA), Galacturonic acid (GalA), Rhamnose (Rha), Glucose (Glc), Galactose (Gal), and Arabinose (Ara), at a molar ratio of 0.01:0.11:0.03:0.57:0.02:0.32:1. The molecular weight of CSP-III was 4018234 Da. Meanwhile, the capacity of CSP-III, at various concentrations, to stimulate the proliferation of mouse spleen lymphocytes in vitro was compared, and the influence of CSP-III on cell proliferation was examined using RAW264.7 mouse mononuclear macrophages as a model. The influence of CSP-III on the expression of important phosphorylating proteins in the MAPK signaling pathway was initially analyzed by Western blotting. In RAW264.7 cells, CSP-III promoted the phosphorylation of JNK proteins, which thus activated the MAPK signaling cascade and exerted immunomodulatory effects. Moreover, according to in vivo studies using cyclophosphamide (CTX)-induced immunosuppression mouse models, CSP-III improved the CTX-induced histopathological damage, promoted T and B lymphocyte proliferation, upregulated CD4+ and CD8+ T-lymphocyte counts in the spleen, increased the serum levels of IgG and IgM, and activated three essential proteins of the MAPK signaling pathway. As revealed by analysis of intestinal flora, CSP-III improved the immune function by maintaining the homeostasis of the bacterial flora by boosting the relative abundances of some beneficial bacterial groups, such as Bacteroidetes, Desmodium, and Actinomyces, and reducing the relative abundance of Aspergillus phylum. Through in vitro and in vivo experiments, our present study demonstrates that polysaccharides from the stem of Cynomorium songaricum possess strong immunoregulatory effects. Findings in this work provide theoretical support for the potential application of Cynomorium songaricum in the field of health food.


Assuntos
Cynomorium , Humanos , Animais , Camundongos , Imunomodulação , Terapia de Imunossupressão , Ativação Linfocitária , Sistema de Sinalização das MAP Quinases
20.
Molecules ; 28(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138445

RESUMO

Alzheimer's disease is a common degenerative disease which has a great impact on people's daily lives, but there is still a certain market gap in the drug research about it. Palmatine, one of the main components of Huangteng, the rattan stem of Fibraurea recisa Pierre (Menispermaceae), has potential in the treatment of Alzheimer's disease. The aim of this study was to evaluate the neuroprotective effect of palmatine on amyloid beta protein 25-35-induced rat pheochromocytoma cells and AD mice and to investigate its mechanism of action. CCK8 assays, ELISA, the Morris water maze assay, fluorescent probes, calcein/PI staining, immunofluorescent staining and Western blot analysis were used. The experimental results show that palmatine can increase the survival rate of Aß25-35-induced PC12 cells and mouse hippocampal neurons, reduce apoptosis, reduce the content of TNF-α, IL-1ß, IL-6, GSH, SOD, MDA and ROS, improve the learning and memory ability of AD mice, inhibit the expression of Keap-1 and Bax, and promote the expression of Nrf2, HO-1 and Bcl-2. We conclude that palmatine can ameliorate oxidative stress and neuroinflammation produced by Aß25-35-induced PC12 cells and mice by modulating the Nrf2/HO-1 pathway. In conclusion, our results suggest that palmatine may have a potential therapeutic effect on AD and could be further investigated as a promising therapeutic agent for AD. It provides a theoretical basis for the development of related drugs.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Humanos , Ratos , Camundongos , Animais , Peptídeos beta-Amiloides/toxicidade , Peptídeos beta-Amiloides/metabolismo , Células PC12 , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças Neuroinflamatórias , Estresse Oxidativo
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