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1.
Chem Biodivers ; 20(9): e202300693, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37614210

RESUMO

Chemical investigation on the water-soluble constituents of Stemona tuberosa Lour. resulted in the isolation of a previously undescribed furfural derivative namely (S)-5-((R)-hydroxy(5-(hydroxymethyl)furan-2-yl)methyl)-5-methylfuran-2(5H)-one and twenty-five known compounds from the water decoction of the dried root tubers. Their structures were determined by analysis of the extensive spectroscopic data, including 1D/2D NMR, HR-ESI-MS, and ORD, as well as the ECD simulation and comparison. Most of them were phenolic and among them, four compounds were isolated from Stemona plants for the first time. This study uncovers diverse constituents from water decoction of S. tuberosa dedicated for its quality control and allows for the exploitation of chemical markers with potential significance for discrimination of Stemona plants.


Assuntos
Alcaloides , Stemonaceae , Alcaloides/química , Stemonaceae/química , Furaldeído/análise , Tubérculos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
2.
Toxicol Appl Pharmacol ; 438: 115908, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35123989

RESUMO

Gastric cancer is one of the most common cancers with few effective treatments, a new treatment agent is desperately needed. C-2, a Jaspine B derivative, has shown anti-cancer efficacy in gastric cancer cells. The anti-cancer mechanism, however, remains unknown. As a result, we investigate the anti-cancer effect and the underlying mechanism of C-2 in gastric cancer cells. The results showed that C-2 selectively reduced the proliferation of gastric cancer cells when compared to normal epithelial gastric cells. Western blotting and flow cytometry further demonstrated that Caspase9 is involved in causing cell death. Meanwhile, C-2 triggered autophagy in gastric cancer cells, inhibition of which with LY294002 can enhance the anti-proliferative activity of C-2. Next, we found that C-2 triggered autophagy through activating JNK/ERK, and that inhibitors of these proteins exacerbated C-2 induced cell death. Mechanically, enhanced phosphorylation of JNK/ERK elevated Beclin-1 by disturbing Beclin-1/Bcl-xL or Beclin-1/Bcl-2 complexes, resulting in autophagy and up-regulation of p62. Finally, p62 binds Keap1 competitively to release Nrf2, boosting Nrf2 translocation from the cytoplasm to the nucleus and triggering expression of Nrf2 target genes, so enhancing survival. C-2 inhibited the growth of gastric cancer cells, while JNK/ERK dependent autophagy antagonized C-2 induced cell growth inhibition through p62/Keap1/Nrf2 pathway.


Assuntos
Autofagia/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas de Ligação a RNA/metabolismo , Esfingosina/análogos & derivados , Neoplasias Gástricas/tratamento farmacológico , Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HEK293 , Humanos , MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Esfingosina/farmacologia , Neoplasias Gástricas/metabolismo
3.
Ann Noninvasive Electrocardiol ; 27(4): e12966, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35567783

RESUMO

BACKGROUND: Complete right bundle branch block (CRBBB) is an important predictor of atrial fibrillation (AF) recurrence after pulmonary vein isolation. However, the association between CRBBB and AF development remains unclear. METHODS: We performed a retrospective study of 2639 patients (male, n = 1549; female, n = 1090; mean age, 58 ± 13 years). CRBBB was defined as a late R (R') wave in lead V1 or V2 with a slurred S wave in lead I and/or lead V6 with a prolonged QRS duration (≥120 ms). RESULTS: Among the 2639 patients, CRBBB was detected in 40 patients (1.5%), and the prevalence of AF was 7.4% (196/2639). The proportion of patients with AF and CRBBB was higher than the proportion of patients with AF without CRBBB (22.5% vs. 7.2%; p = 0.001). In the forward multivariate logistic analysis, CRBBB (odds ratio [OR], 3.329; 95% confidence interval [CI], 1.350-8.211; p = 0.009), complete left bundle branch block (OR, 2.209; 95% CI, 1.238-3.940; p = 0.007), age (OR, 1.020; 95% CI, 1.005-1.035; p = 0.009), valvular heart disease (OR, 2.332; 95% CI, 1.531-3.552; p < 0.001), left atrial diameter (OR, 1.133; 95% CI, 1.104-1.163; p < 0.001), left ventricular ejection fraction (OR, 1.023; 95% CI, 1.006-1.041; p = 0.007), and class I or III anti-arrhythmic drug use (OR, 10.534; 95% CI, 7.090-15.651; p < 0.001) were associated with AF. CONCLUSION: Complete right bundle branch block was significantly associated with AF development in hospitalized patients with cardiovascular diseases.


Assuntos
Fibrilação Atrial , Bloqueio de Ramo , Idoso , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Bloqueio de Ramo/complicações , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/epidemiologia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
4.
BMC Cardiovasc Disord ; 21(1): 587, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876011

RESUMO

BACKGROUND: In patients with atrial fibrillation (AF) and functional mitral regurgitation (MR), catheter ablation reduces the severity of MR and improves cardiac remodeling. However, its effects on prognosis are uncertain. METHODS: This retrospective study included 151 consecutive patients with AF and functional MR, 82 (54.3%) of whom were treated by catheter ablation (Ablation group) and 69 (45.7%) with drug therapy without ablation (Non-ablation group). Forty-three pairs of these patients were propensity matched on the basis of age, CHA2DS2-VASc scores, and left ventricular ejection fraction. The primary outcome evaluated was severity of MR, cardiac remodeling and the combined incidence of subsequent heart failure-related hospitalization and strokes/transient ischemic attacks. RESULTS: Patients in the Ablation group showed a significant decrease in the severity of MR (p < 0.001), a significant decrease in the left atrial diameter (p = 0.010), and significant improvement in the left ventricular ejection fraction (p = 0.015). However, patients in the Non-ablation group showed only a significant decrease in the severity of MR (p = 0.004). The annual incidence of the studied events was 4.9% in the Ablation group and 16.7% in the Non-ablation group, the incidence being significantly lower in the ablation than Non-ablation group (p = 0.026) according to Kaplan-Meier curve analyses. According to multivariate Cox regression analysis, catheter ablation therapy (hazard ratio [HR] 0.27, 95% confidence interval [CI] 0.09-0.84; p = 0.024) and heart failure at baseline (HR 3.84, 95% CI 1.07-13.74; p = 0.038) were independent predictors of the incidence of the studied events. CONCLUSIONS: Among patients with AF and functional MR, catheter ablation was associated with a significantly lower combined risk of heart failure-related hospitalization and stroke than in a matched cohort of patients receiving drug therapy alone.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/terapia , Ablação por Cateter , Insuficiência da Valva Mitral/fisiopatologia , Valva Mitral/fisiopatologia , Potenciais de Ação , Idoso , Antiarrítmicos/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Frequência Cardíaca , Humanos , Ataque Isquêmico Transitório/etiologia , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/diagnóstico por imagem , Recuperação de Função Fisiológica , Estudos Retrospectivos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
5.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4230-4237, 2021 Aug.
Artigo em Zh | MEDLINE | ID: mdl-34467737

RESUMO

This study aimed to explore the mechanism of Xiaoyao San(XYS) in the treatment of three diseases of liver depression and spleen deficiency, ie, depression, breast hyperplasia, and functional dyspepsia, and to provide a theoretical basis for the interpretation of the scientific connotation of "treating different diseases with the same method" of traditional Chinese medicines. Traditional Chinese medicine systems pharmacology database and analysis platform(TCMSP) was used to screen the active components of XYS which underwent principal component analysis(PCA) with the available drugs for these three diseases to determine the corresponding biological activities. The targets of XYS on depression, breast hyperplasia, and functional dyspepsia were obtained from GeneCards, TTD, CTD, and DrugBank databases. Cytoscape was used to plot the "individual herbal medicine-active components-potential targets" network. The resulting key targets were subjected to Kyoto encyclopedia of genes and genomes(KEGG) pathway analysis and gene ontology(GO) enrichment analysis. A total of 121 active components of XYS and 38 common targets in the treatment of depression, breast hyperplasia, and functional dyspepsia were collected. The key biological pathways were identified, including advanced glycation and products(AGEs)-receptor for advanced glycation and products(RAGE) signaling pathway in diabetic complications, HIF-1 signaling pathway, and cancer-related pathways. The key targets of XYS in the treatment of depression, breast hyperplasia, and functional dyspepsia included IL6, IL4, and TNF, and the key components were kaempferol, quercetin, aloe-emodin, etc. As revealed by the molecular docking, a strong affinity was observed between the key components and the key targets, which confirmed the results. The therapeutic efficacy of XYS in the treatment of diseases of liver depression and spleen deficiency was presumedly achieved by reducing the inflammatory reactions. The current findings are expected to provide novel research ideas and approaches to classify the scientific connotation of "treating different diseases with the same method" of Chinese medicines, as well as a theoretical basis for understanding the mechanism of XYS and exploring its clinical applications.


Assuntos
Medicamentos de Ervas Chinesas , Dispepsia , Depressão/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Dispepsia/tratamento farmacológico , Humanos , Hiperplasia/tratamento farmacológico , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular
6.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3776-3783, 2020 Aug.
Artigo em Zh | MEDLINE | ID: mdl-32893570

RESUMO

Depression is a common affective disorder. The application of antidepressants can significantly alleviate the symptoms of depression, which is the most important way to treat depression in clinical practice. Due to the complex etiology, wide variety, as well as diversity and severity of serious concomitant symptoms, rational addition of other drugs into antidepressants can significantly improve the cure rates of depression, reduce adverse reactions, and improve patient compliances. Therefore, the combined applications of differential drugs have been commonly used in clinic. In this paper, more than 600 literatures about depression from 2010 to 2019 were collected based on the key words of antidepressant, depression, combined medication, synergism and increase efficiency. Based on this, by summarizing and classifying the existing combinations of antidepressant drugs, this paper systematically expounds the current combined applications of antidepressant drugs in three categories, i.e. western medicines combined with western medicines, western medicines combined with traditional Chinese medicines, and traditional Chinese medicines combined with traditional Chinese medicines, in the expectation of providing the direction and basis for the selection of rational combinations of antidepressant drugs in clinic.


Assuntos
Antidepressivos , Medicina Tradicional Chinesa , Interações Medicamentosas , Humanos
7.
Horm Behav ; 83: 83-92, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27222435

RESUMO

Alzheimer's disease (AD) is an age-related mental disorder characterized by progressive loss of memory and multiple cognitive impairments. The overproduction and aggregation of Amyloid ß protein (Aß) in the brain, especially in the hippocampus, are closely involved in the memory loss in the patients with AD. Accumulating evidence indicates that the Aß-induced imbalance of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) in the brain plays an important role in the AD pathogenesis and progression. The level of DHEA is elevated, while DHEAS is dramatically decreased in the AD brain. The present study tried to restore the balance between DHEA and DHEAS by using a non-steroidal sulfatase inhibitor DU-14, which increases endogenous DHEAS through preventing DHEAS converted back into DHEA. We found that: (1) DU-14 effectively attenuated the Aß1-42-induced cognitive deficits in spatial learning and memory of rats in Morris water maze test; (2) DU-14 prevented Aß1-42-induced decrease in the cholinergic theta rhythm of hippocampal local field potential (LFP) in the CA1 region; (3) DU-14 protected hippocampal synaptic plasticity against Aß1-42-induced suppression of long term potentiation (LTP). These results provide evidence for the neuroprotective action of DU-14 against neurotoxic Aß, suggesting that up-regulation of endogenous DHEAS by DU-14 could be beneficial to the alleviation of Aß-induced impairments in spatial memory and synaptic plasticity.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Plasticidade Neuronal/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Memória Espacial/efeitos dos fármacos , Esteril-Sulfatase/antagonistas & inibidores , Tiramina/análogos & derivados , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/prevenção & controle , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/prevenção & controle , Ratos , Ratos Sprague-Dawley , Tiramina/farmacologia , Regulação para Cima/efeitos dos fármacos
8.
Hippocampus ; 25(3): 363-72, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25332198

RESUMO

Amyloid ß peptide (Aß) has been thought to be neurotoxic and responsible for the impairment of learning and memory in Alzheimer's disease (AD). Humanin (HN), a 24 amino acid polypeptide first identified from the unaffected occipital lobe of an AD patient, is believed to be neuroprotective against the AD-related neurotoxicity. In this study, we investigated the neuroprotective effects of Colivelin (CLN), a novel HN derivative, against Aß by using behavioral test, in vivo electrophysiological recording, and intracellular calcium imaging. Our results showed that intrahippocampal injection of CLN (0.2 nmol) effectively prevented Aß25-35 (4 nmol)-induced deficits in spatial learning and memory of rats in Morris water maze test; the suppression of in vivo hippocampal long term potentiation (LTP) by Aß25-35 was nearly completely prevented by CLN; in addition, CLN pretreatment also effectively inhibited Aß25-35-induced calcium overload in primary cultured hippocampal neurons. These results indicate that CLN has significant neuroprotective properties against Aß, and CLN may holds great promise for the treatment and prevention of AD.


Assuntos
Cálcio/metabolismo , Homeostase/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Plasticidade Neuronal/efeitos dos fármacos , Peptídeos beta-Amiloides/toxicidade , Animais , Células Cultivadas , Hipocampo/citologia , Potenciação de Longa Duração/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Ratos , Ratos Sprague-Dawley
9.
Horm Behav ; 73: 125-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26135065

RESUMO

ß-Amyloid (Aß) is the main component of amyloid plaques developed in the brain of patients with Alzheimer's disease (AD). The increasing burden of Aß in the cortex and hippocampus is closely correlated with memory loss and cognition deficits in AD. Recently, leptin, a 16kD peptide derived mainly from white adipocyte tissue, has been appreciated for its neuroprotective function, although less is known about the effects of leptin on spatial memory and synaptic plasticity. The present study investigated the neuroprotective effects of leptin against Aß-induced deficits in spatial memory and in vivo hippocampal late-phase long-term potentiation (L-LTP) in rats. Y maze spontaneous alternation was used to assess short term working memory, and the Morris water maze task was used to assess long term reference memory. Hippocampal field potential recordings were performed to observe changes in L-LTP. We found that chronically intracerebroventricular injection of leptin (1µg) effectively alleviated Aß1-42 (20µg)-induced spatial memory impairments of Y maze spontaneous alternation and Morris water maze. In addition, chronic administration of leptin also reversed Aß1-42-induced suppression of in vivo hippocampal L-LTP in rats. Together, these results suggest that chronic leptin treatments reversed Aß-induced deficits in learning and memory and the maintenance of L-LTP.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Hipocampo/efeitos dos fármacos , Leptina/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Memória Espacial/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Animais , Hipocampo/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/fisiopatologia , Transtornos da Memória/prevenção & controle , Memória de Curto Prazo/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Sprague-Dawley
10.
Hippocampus ; 24(1): 44-53, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23996574

RESUMO

Rattin, a specific derivative of humanin in rats, shares the ability with HN to protect neurons against amyloid ß (Aß) peptide-induced cellular toxicity. However, it is still unclear whether Rattin can protect against Aß-induced deficits in cognition and synaptic plasticity in rats. In the present study, we observed the effects of Rattin and Aß31-35 on the spatial reference memory and in vivo hippocampal Long-term potentiation of rats by using Morris water maze test and hippocampal field potential recording. Furthermore, the probable molecular mechanism underlying the neuroprotective roles of Rattin was investigated. We showed that intra-hippocampal injection of Rattin effectively prevented the Aß31-35-induced spatial memory deficits and hippocampal LTP suppression in rats; the Aß31-35-induced activation of Caspase-3 and inhibition of STAT3 in the hippocampus were also prevented by Rattin treatment. These findings indicate that Rattin treatment can protect spatial memory and synaptic plasticity of rats against Aß31-35-induced impairments, and the underlying protective mechanism of Rattin may be involved in STAT3 and Caspases-3 pathways. Therefore, application of Rattin or activation of its signaling pathways in the brain might be beneficial to the prevention of Aß-related cognitive deficits.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Potenciação de Longa Duração/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas/farmacologia , Doença de Alzheimer/metabolismo , Animais , Caspase 3/biossíntese , Modelos Animais de Doenças , Citometria de Fluxo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT3/biossíntese
11.
Sheng Li Xue Bao ; 66(2): 97-106, 2014 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-24777399

RESUMO

Hippocampal neuronal network oscillation is closely related to the memory, anxiety and behavioral inhibition of mammalian. The cognitive decline and behavioral disinhibition in the patients with Alzheimer's disease (AD) may be relevant to amyloid ß protein (Aß)-induced impairment in hippocampal neuronal cooperative activity. However, it is not well known whether intrahippocampal injection of Aß could induce behavioral disinhibition and neuronal network disorder, as well as cognition decline in animals. In the present study, we observed the effects of intracerebral injection of Aß(1-42) on the spatial memory and behavioral inhibition of rats by using Morris water maze and elevated plus-maze tests. Further, we analyzed hippocampal theta rhythm by recording hippocampal local field potential. The results showed that: (1) bilateral hippocampal injection of Aß(1-42) reduced the anxious behavior of rats, with a significant behavioral disinhibition in the elevated plus-maze test, representing as an increase in the mean entering times and mean residence time in the open arm; (2) Aß(1-42) injection resulted in a significant impairment of spatial memory in rats, with significantly increased mean escape latencies in hidden platform test; (3) Aß(1-42) disrupted the induction of theta rhythm induced by tail pinch, with a significant reduction in the peak power, not the peak power frequency of the theta rhythm. These experimental results indicate that intrahippocampal injection of Aß(1-42) can induce behavioral disinhibition and theta rhythm suppression, as well as spatial memory impairment in rats, which suggests that the cognition deficits and behavior impairments in AD are probably associated with the Aß-induced disruption of hippocampal theta rhythm and consequent down-regulation of synaptic plasticity.


Assuntos
Peptídeos beta-Amiloides/efeitos adversos , Hipocampo/fisiopatologia , Fragmentos de Peptídeos/efeitos adversos , Memória Espacial , Ritmo Teta , Animais , Regulação para Baixo , Aprendizagem em Labirinto , Plasticidade Neuronal , Ratos
12.
J Hazard Mater ; 476: 135050, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38954852

RESUMO

Spent lithium-ion batteries (LIBs) have emerged as a major source of waste due to their low recovery rate. The physical disposal of spent LIBs can lead to the leaching of their contents into the surrounding environment. While it is widely agreed that hazardous substances such as nickel and cobalt in the leachate can pose a threat to the environment and human health, the overall composition and toxicity of LIB leachate remain unclear. In this study, a chemical analysis of leachate from spent LIBs was conducted to identify its primary constituents. The ecotoxicological parameters of the model organism, rotifer Brachionus asplanchnoidis, were assessed to elucidate the toxicity of the LIB leachate. Subsequent experiments elucidated the impacts of the LIB leachate and its representative components on the malondialdehyde (MDA) level, antioxidant capacity, and enzyme activity of B. asplanchnoidis. The results indicate that both the LIB leachate and its components are harmful to individual rotifers due to the adverse effects of stress-induced disturbances in biochemical indicators, posing a threat to population development. The intensified poisoning phenomenon under combined stress suggests the presence of complex synergistic effects among the components of LIB leachate. Due to the likely environmental and biological hazards, LIBs should be strictly managed after disposal. Additionally, more economical and eco-friendly recycling and treatment technologies need to be developed and commercialized.


Assuntos
Lítio , Malondialdeído , Estresse Oxidativo , Rotíferos , Poluentes Químicos da Água , Animais , Rotíferos/efeitos dos fármacos , Lítio/toxicidade , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Fontes de Energia Elétrica , Antioxidantes/metabolismo
13.
J Colloid Interface Sci ; 668: 161-170, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38677205

RESUMO

CO2-to-high value-added chemicals via a photocatalytic route is of interest but strangled by the low efficiency. Herein, a novel Fe-TiO2-x/TiO2 S-scheme homojunction was designed and constructed by using a facile surface modification approach whereby oxygen vacancy (OV) and Fe introducing on the TiO2 nanorod surface. The as-synthesized Fe-TiO2-x/TiO2 S-scheme homojunction exhibits positive properties on promoting photocatalytic CO2 reduction: i) the nanorod structure provides numerous active sites and a radical charge transfer path; ii) the doped Fe and OV not only synergistically enhance light utilization but also promote CO2 adsorption; iii) the Fe-TiO2-x/TiO2 S-scheme homojunction benefits photoexcited charge separation and retains stronger redox capacity. Thanks to those good characters, the Fe-TiO2-x/TiO2 homojunction exhibits superior CO2 reduction performances with optimized CO/CH4 generation rates of 122/22 µmol g-1h-1 which exceed those of pure TiO2 by more than 9.4/7.3 folds and most currently reported catalytic systems. This manuscript develops a facile and universal approach to synthesize well-defined homojunction and may inspire the construction of other more high-efficiency photocatalysts toward CO2 reduction and beyond.

14.
Synapse ; 67(9): 626-36, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23620224

RESUMO

Alzheimer's disease (AD), the most prevalent neurodegenerative disease in the elderly, leads to progressive loss of memory and cognitive deficits. Amyloid-ß protein (Aß) in the brain is thought to be the main cause of memory loss in AD. Melatonin, an indole hormone secreted by the pineal gland, has been reported to produce neuroprotective effects. We examined whether melatonin could protect Aß-induced impairments of hippocampal synaptic plasticity, neuronal cooperative activity, and learning and memory. Rats received bilateral intrahippocampal injection of Aß1-42 or Aß31-35 followed by intraperitoneal application of melatonin for 10 days, and the effects of chronic melatonin treatment on in vivo hippocampal long-term potentiation (LTP) and theta rhythm and Morris water maze performance were examined. We showed that intrahippocampal injection of Aß1-42 or Aß31-35 impaired hippocampal LTP in vivo, while chronic melatonin treatment reversed Aß1-42- or Aß31-35-induced impairments in LTP induction. Intrahippocampal injection of Aß31-35 impaired spatial learning and decreased the power of theta rhythm in the CA1 region induced by tail pinch, and these synaptic, circuit, and learning deficits were rescued by chronic melatonin treatment. These results provide evidence for the neuroprotective action of melatonin against Aß insults and suggest a strategy for alleviating cognition deficits of AD.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Melatonina/farmacologia , Fragmentos de Peptídeos/toxicidade , Peptídeos beta-Amiloides/administração & dosagem , Animais , Hipocampo/metabolismo , Hipocampo/fisiologia , Injeções Intraperitoneais , Injeções Intraventriculares , Masculino , Melatonina/administração & dosagem , Memória/efeitos dos fármacos , Fragmentos de Peptídeos/administração & dosagem , Ratos , Ratos Sprague-Dawley
15.
Sci Total Environ ; 857(Pt 1): 159403, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36243066

RESUMO

China's carbon emissions have developed swiftly in recent decades, which will not only affect the nation's own sustainable development, but have a potentially negative impact on global climate stability. Given that socioeconomic development is susceptible to regional heterogeneity and geographic scales, a systematic exploration of spatiotemporal variations of carbon emission intensity (CEI) and their drivers across different levels is conducive to enacting more reasonable and efficient measures for emission reduction. However, there is still a lack of comprehensive analysis of these issues. In this paper, we attempted to quantify and compare the spatiotemporal evolution and spatial spillover effects of impact factors on CEI from nighttime light imagery and socioeconomic data at two China's administrative levels by utilizing the variation coefficient, spatial autocorrelation model and spatial econometric methods. The results showed that the spatiotemporal variations of CEI were greater at the prefecture level compared to the provincial level during 2000-2017. There were significant positive spatial autocorrelation of CEI at two administrative levels, and self-reinforcing agglomeration was more substantial at the prefectural level than that provincial level. While the local spatial clustering of CEI of each administrative level altered with scale dependence, the binary spatial structure (High-High and Low-Low) of CEI remained relatively steady in China. Various driver factors not only had direct effects on local CEI, but had spatial spillover effects on neighboring areas. Our findings illustrate that China's CEI is sensitive to the space-time hierarchy of multi-mechanisms, and suggest that "proceed in the light of local conditions" strategies can assist the Chinese government for CEI mitigation.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , Análise Espacial , China , Desenvolvimento Econômico
16.
Toxicol Res (Camb) ; 12(2): 201-215, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37125330

RESUMO

Introduction: Qishenbuqi capsule (QSBQC), a listed Chinese patent prescription, comprises of 4 herbs. Clinically, it has been shown to improve immune functions. Methods: Subjects with Qi deficiency and non-Qi deficiency were recruited, who then took QSBQC for 4 weeks. Traditional Chinese medicine (TCM) syndrome scores and the levels of white blood cells, CD3+ T cells (CD3+), CD4+ T cells (CD3+CD4+), CD8+ T cells (CD3+CD8+), and CD4+/CD8+ were determined. Serum metabolomics was used to explore the metabolic mechanisms of QSBQC on improving immunity. Meanwhile, the potential active ingredients, targets, and pathways of QSBQC on enhancing immunity were screened by network pharmacology. Results: QSBQC significantly improved TCM syndrome scores and increased the number of CD8+ T cells of both Qi deficiency and non-Qi deficiency subjects. Serum metabolomics revealed that QSBQC regulated 18 differential metabolites and 8 metabolic pathways of Qi deficiency, and 12 differential metabolites and 7 metabolic pathways of non-Qi deficiency subjects. The "herbs-compounds-pathways" diagram showed that PQ-2, cimifugin, and divaricatol were the main active components. Pathways in cancer and arginine and proline metabolism could be the most important pathways. Conclusion: Our research revealed the immunoenhancing mechanisms of QSBQC and improved the combination of TCM theory and modern western medicine theory.

17.
Magn Reson Chem ; 50(3): 187-92, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22367791

RESUMO

Chronic unpredictable mild stress (CUMS) is a well-validated model of depression. In this study, a urinary metabonomics method based on the NMR spectrometry was used to study the metabolic perturbation in CUMS-induced rat depression model. With pattern recognition analysis, a clear separation of CUMS rats and healthy controls was achieved, and nine endogenous metabolites contributing to the separation were identified. CUMS-treated rats were characterized by the increase of glycine, pyruvate, glutamine, and asparagines, as well as the decrease of 2-oxoglutarate, dimethylglycine, citrate, succinate, and acetate. The urinary biochemical changes related to the metabolic disturbance in CUMS induced depression, and the possible correlations with live qi stagnation in traditional Chinese medicine are discussed. The work shows that CUMS is a reliable model for studying depression, and the noninvasive urinary metabolomic method is a valuable tool to investigate the biochemical pertubations in depression as an early diagnostic means.


Assuntos
Ácidos/urina , Aminas/urina , Aminoácidos/urina , Depressão/urina , Modelos Animais de Doenças , Estresse Fisiológico , Ácidos/metabolismo , Aminas/metabolismo , Aminoácidos/metabolismo , Animais , Comportamento Animal , Depressão/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley
18.
Sheng Li Xue Bao ; 64(1): 87-95, 2012 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-22348966

RESUMO

Alzheimer's disease (AD) has become one of the most important and most interesting focuses in the field of medical and scientific research. Up to now, the pathogenesis of AD has not been completely clarified. However, the high-density of amyloid ß-protein (Aß) in senile plaques of AD brain and the neurotoxicity of Aß have been indisputable facts. The mechanisms underlying Aß neurotoxicity are very complicated, involving calcium overload, inflammation, ion channel dysfunction, oxidative stress and so on. Among all of those, the mechanism of oxidative stress in Aß neurotoxicity and the experimental progress of antioxidants in AD treatment have been widely reported in recent years. This review mainly discussed current research progresses on the oxidative stress of Aß, so as to provide readers with some clues to the antioxidant therapy of AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/efeitos adversos , Antioxidantes/farmacologia , Estresse Oxidativo/fisiologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Humanos , Estresse Oxidativo/efeitos dos fármacos
19.
Sheng Li Xue Bao ; 64(6): 625-32, 2012 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-23258324

RESUMO

Amyloid ß protein (Aß) is closely involved in the pathogenesis of Alzheimer's disease (AD), and one of the main strategies for AD treatment is antagonizing the neurotoxicity of Aß or even clearing the Aß deposited in the brain. The present study was aimed to observe the effects of intrahippocampal injection of Aß31₋35 on the spatial learning and memory of rats by using Morris water maze technique, and explore the neuroprotective effects and possible mechanism of [Gly14]-humanin (HNG) against Aß-induced deficits in learning behavior. The results showed that bilateral intrahippocampal injection of 2.0 nmol Aß31₋35 significantly increased the mean traveled distance of rats in searching for the hidden underwater platform and decreased the distance percentage in the target quadrant in probe test after withdrawal of platform, whereas pretreatment with HNG (0.2 nmol and 2.0 nmol) suppressed Aß31₋35-induced increase in the traveled distance and decrease in swimming distance percentage. Application of Genistein (40 nmol), a specific tyrosine kinase inhibitor, almost completely blocked the antagonistic effects of HNG against Aß31₋35. These results indicate that HNG can dose-dependently prevent against Aß31₋35-induced impairment in spatial learning and memory of rats, and the neuroprotective effects of HNG might involve the activation of endogenous tyrosine kinase pathway, suggesting that up-regulation of the tyrosine kinase signaling by using HNG might be of great significance for the improvement of cognitive function in AD.


Assuntos
Peptídeos beta-Amiloides/efeitos adversos , Memória/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos adversos , Peptídeos/farmacologia , Aprendizagem Espacial/efeitos dos fármacos , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Animais , Encéfalo/efeitos dos fármacos , Genisteína/farmacologia , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Ratos
20.
Huan Jing Ke Xue ; 43(3): 1190-1200, 2022 Mar 08.
Artigo em Zh | MEDLINE | ID: mdl-35258183

RESUMO

Based on ground monitoring data, we explored the spatiotemporal characteristics and drivers of PM2.5 in the Yangtze River Economic Belt (YREB) in 2018 using spatial autocorrelation analysis and geodetector modeling methods. The results showed that:① the PM2.5 concentration in the YREB posed the obvious characteristics of low values in summer and high values in winter, seasonal variation in spring and autumn, monthly U-shaped variation, and daily pulse variation. The low value area was mainly concentrated in the south bank of the upper reaches, whereas the high value area was located in the north of the middle-lower reaches of the YREB. ② PM2.5 pollution in the YREB had a stable positive spatial correlation, and the local association pattern showed a significant HH and LL spatial convergence. ③ The spatial correlation of PM2.5 in the YREB decreased with the increase in geographical distance, and its spatial autocorrelation threshold was approximately 870 km, within which the spatial agglomeration of PM2.5 pollution was strong. ④ The influences of natural and anthropogenic factors on PM2.5 had significant spatial differences. Altitude, relief, and population density were the high impact factors of PM2.5 pollution in the YREB. The interaction of factors had a far greater explanatory power on PM2.5 pollution than that of single factors. The dominant interaction factor was industrial structure ∩ altitude, which reflected the complexity of the drivers of air pollution in the YREB.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Poluição Ambiental/análise , Indústrias , Material Particulado/análise , Rios
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