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1.
Brain Sci ; 13(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37508937

RESUMO

Previous studies have suggested that microwave (MW) radiation with certain parameters can induce spatial memory deficits. However, the effect of MW on the topological organization of the brain network is still unknown. This work aimed to investigate the topological organization of the brain network in rats with spatial memory impairments induced by acute microwave (MW) radiation. The Morris water maze (MWM) test and resting-state functional magnetic resonance imaging were performed to estimate the spatial memory ability and brain network topological organization of the rats after MW exposure. Compared with the sham group, the rats exposed to 30 mW/cm2 1.5 GHz MW radiation exhibited a significantly decreased normalized clustering coefficient (γ) (p = 0.002) 1 d after the exposure and a prolonged average escape latency (AEL) (p = 0.014) 3 d after the exposure. Moreover, after 10 mW/cm2 1.5 GHz MW radiation, a significantly decreased γ (p = 0.003) was also observed in the rats, without any changes in AEL. In contrast, no adverse effects on AEL or topological parameters were observed after 9.375 GHz MW radiation. In conclusion, the rats with spatial memory deficits induced by MW radiation exhibited disruptions in the topological organization of the brain network. Moreover, these topological organization disruptions emerged earlier than behavioral symptom onset and could even be found in the rats without a decline in the performance of the spatial memory task. Therefore, it is possible to use the topological parameters of the brain network as early and sensitive indicators of the spatial memory impairments induced by acute MW radiation.

2.
Front Plant Sci ; 13: 973662, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051297

RESUMO

Although grazing is the most common use of grassland, the ecological function of grassland far exceeds its productivity. Therefore, the protection of plant diversity is of the utmost importance and cannot be ignored. Existing research on the effect of grazing on grassland mainly focuses on grazing intensity and the type of livestock, but the consequences of the timing of the grazing on the vegetation community remains unclear. We investigated plant community characteristics of winter pastures in alpine meadow with different grazing termination times (grazing before and during the grassland greenup periods) in Maqu County, eastern QTP. The results showed that vegetation height, coverage, aboveground biomass and Graminoid biomass were lower in grassland when grazing happened during the greenup period compared to grassland where grazing was terminated before the greenup period. However, the total plant species richness and forbs richness were higher in grassland with grazing during the greenup period compared to grassland without grazing during the greenup period. Our structural equation modeling reveals a potential indirect implication for the total plant species richness and forbs richness of winter pastures mainly through a decrease in the vegetation coverage and grass biomass abundance. Our findings imply that grazing during the grassland greenup period may facilitate the maintenance of plant diversity in winter pastures. These findings have important implications for grassland ecosystem functioning and for the conservation of plant diversity.

3.
Int J Mol Sci ; 23(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36012537

RESUMO

Electromagnetic pulse (EMP) radiation was reported to be harmful to hippocampal neurons. However, the mechanism underlying EMP-induced neuronal damage remains unclear. In this paper, for the first time, we attempted to investigate the involvement of ferroptosis in EMP-induced neuronal damage and its underlying mechanism. In vivo studies were conducted with a rat model to examine the association of ferroptosis and EMP-induced hippocampal neuronal damage. Moreover, in vitro studies were conducted with HT22 neurons to investigate the underlying mechanism of EMP-induced neuronal ferroptosis. In vivo results showed that EMP could induce learning and memory impairment of rats, ferroptotic morphological damages to mitochondria, accumulation of malonaldehyde (MDA) and iron, overexpression of prostaglandin-endoperoxide synthase 2 (PTGS2) mRNA, and downregulation of GPX4 protein in rat hippocampus. In vitro results showed that EMP could induce neuronal death, MDA accumulation, iron overload, PTGS2 overexpression, and GPX4 downregulation in HT22 neurons. These adverse effects could be reversed by either lipid peroxides scavenger ferrostatin-1 or overexpression of GPX4. These results suggest that EMP radiation can induce ferroptosis in hippocampal neurons via a vicious cycle of lipid peroxides accumulation and GSH/GPX4 axis downregulation. Lipid peroxides and the GSH/GPX4 axis provide potential effective intervention targets to EMP-induced hippocampal neuronal damage.


Assuntos
Ferroptose , Animais , Ciclo-Oxigenase 2/metabolismo , Fenômenos Eletromagnéticos , Hipocampo/metabolismo , Peróxidos Lipídicos , Neurônios/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Ratos
4.
Psychooncology ; 31(4): 661-670, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34784087

RESUMO

OBJECTIVE: Financial hardship among older cancer survivors has not been well-studied, despite its debilitating effects on their health and well-being. The purpose of this study was to describe the lived experiences of Chinese older cancer survivors who have experienced financial hardship following a cancer diagnosis. METHODS: A qualitative study was conducted. Data was collected using in-depth interviews with 21 older cancer survivors (aged ≥ 60) with financial hardship and 20 family caregivers in Shandong Province, China between August 2020 and January 2021. Data were analyzed using Colaizzi's phenomenological method. RESULTS: Four main themes emerged: (1) older survivors have insufficient ability to address cancer-related costs; (2) financial transfers from adult children to older parents became prevalent after a cancer diagnosis; (3) cancer-related financial worries and stress extended into children's families; (4) coping and adjustment strategies were used by the extended family. Traditional Confucian culture and the Chinese health care system considerably impacted the interpretation of financial hardship. CONCLUSION: Both older cancer survivors and their adult children experienced financial distress impacted by filial piety in China. Strategies adapted to Confucian family values and the health care system are needed to address cancer-related financial hardships.


Assuntos
Sobreviventes de Câncer , Neoplasias , Adulto , Criança , China , Efeitos Psicossociais da Doença , Estresse Financeiro , Humanos
5.
Life Sci ; 257: 118130, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32710950

RESUMO

BACKGROUND AND OBJECTIVES: Sepsis is a life-threatening organ dysfunction syndrome arising from uncontrolled inflammatory responses. Liver injury is a crucial factor for the prognosis of sepsis. Camptothecins (CPTs) have been reported to suppress the inflammatory response induced by sepsis. G2, a CPT-bile acid conjugate, has been demonstrated the property of liver targeting in our previous research. This study aimed to research the effects of G2 on liver injury induced by cecal ligation and puncture (CLP). METHODS: C57BL/6 mice were subjected to CLP surgery, and effects of G2 on liver damage and survival rates of CLP-induced mice were evaluated. To detect the related markers of hepatic injury or neutrophil infiltration, inflammatory cytokines and protein levels, hematoxylin-eosin staining assay, corresponding Detection Kits assay, ELISA and Western blot analysis were performed. RESULTS: Intraperitoneal administration of G2 reduced liver injury and enhanced the survival rates in mice with sepsis. Treatment with G2 decreased the levels of hepatic injury markers aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the serum of mice induced by CLP. The hepatic level of neutrophil infiltration marker myeloperoxidase (MPO) was reduced in G2 administration group. And the levels of serum inflammatory cytokines, including Tumor Necrosis Factor-α (TNFα), Interleukin-6 (IL-6) and IL-1ß, were decreased by G2. Furthermore, the results of Western blot analysis indicated that G2 suppressed the up-regulation of NF-κB p-P65 and p-IκBα. It suggested that G2 suppressed the activation of NF-κB signaling pathway. CONCLUSION: G2 alleviated sepsis-induced liver injury via inhibiting the NF-κB signaling pathway.


Assuntos
Ácidos e Sais Biliares/uso terapêutico , Camptotecina/uso terapêutico , Hepatopatias/etiologia , NF-kappa B/metabolismo , Sepse/complicações , Transdução de Sinais/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Ácidos e Sais Biliares/administração & dosagem , Western Blotting , Camptotecina/administração & dosagem , Citocinas/sangue , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Hepatopatias/metabolismo , Hepatopatias/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peroxidase/metabolismo
6.
Molecules ; 24(6)2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917485

RESUMO

Camptothecin (CPT) shows potent anticancer activity through inhibition of topoisomerase I. However, its water insolubility and severe toxicity limit its clinical application. Coupling with bile acid moieties is a promising method for liver-targeted drug delivery, which takes advantage of the bile acid receptors on hepatocytes. In this study, we evaluated the potential liver targeting and stability of a deoxycholic acid-CPT conjugate (G2). The competitive inhibition of antitumor activity experiment based on bile acid transporters was performed using the MTT method. The effects of deoxycholic acid on uptake of G2 and CPT were assessed in 2D and 3D HepG2 cell models. The stability of G2 and CPT was evaluated in vitro (in simulated gastric fluid, simulated intestinal fluid, and fresh rat plasma). Finally, biodistribution of G2 and CPT was investigated in Kunming mice following oral administration. The results showed that deoxycholic acid pretreatment could significantly reduce the antitumor activity and cellular uptake of G2 in HepG2 cells, but had no distinct effects on CPT. Meanwhile, G2 exhibited better stability compared with CPT. More importantly, biodistribution study in mice demonstrated that the liver targeting index of G2 increased 1.67-fold than that of CPT. Overall, the study suggests that conjugation with deoxycholic acid is a feasible method to achieve liver targeting delivery of CPT.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/administração & dosagem , Ácido Desoxicólico/química , Fígado/química , Administração Oral , Animais , Camptotecina/química , Camptotecina/farmacocinética , Proliferação de Células/efeitos dos fármacos , Ácido Desoxicólico/administração & dosagem , Estabilidade de Medicamentos , Células Hep G2 , Humanos , Camundongos , Modelos Biológicos , Ratos , Solubilidade , Distribuição Tecidual
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