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1.
PLoS One ; 19(2): e0295443, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38335239

RESUMO

Multinational enterprises frequently divest their foreign assets in the current economic environment. Existing research, based on friction theory, has mainly focused on the impacts of political and economic disparities on foreign divestment while neglecting the nuanced influence of cultural factors. To address this gap, this paper draws on the cultural friction perspective to capture the diverse cultural resistance faced by each enterprise and explore the relationship between cultural friction and foreign divestment. Data from Chinese publicly listed enterprises engaged in foreign investment are leveraged, and a dual-level analysis is conducted using Logit panel regression and Cox survival analysis to examine the relationship between cultural friction and foreign divestment from both the viewpoints of the parent company and the overseas subsidiary. Additionally, the paper examines the marginal factors that affect the relationship between them from an institutional perspective. The findings reveal that cultural friction has a positive influence on the propensity of multinational enterprises to divest from foreign markets. Interestingly, a "formal institutional distance paradox" is demonstrated in our study, and politically connected enterprises are found to be more vulnerable to foreign divestment due to the "curse of political affiliations".


Assuntos
Comércio , Cultura , Investimentos em Saúde , Política , China , Internacionalidade , Investimentos em Saúde/economia , Comércio/economia , Comércio/organização & administração
2.
Biomed Pharmacother ; 168: 115648, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37812892

RESUMO

BACKGROUND: Vimentin, an intermediate filament protein, crucially contributes to the pathogenesis of inflammatory bowel disease (IBD) by interacting with genetic risk factors, facilitating pathogen infection, and modulating both innate and adaptive immune responses. This study aimed to demonstrate preclinical proof-of-concept for targeting vimentin therapeutically in IBD across diverse etiologies. METHODS: The small molecule compound ALD-R491 was assessed for vimentin binding using microscale thermophoresis, off-target effects via Eurofins screening, and therapeutic effects in mice with dextran sulfate sodium (DSS)-induced acute colitis and in IL-10 KO with spontaneous colitis. Parameters measured included body weight, survival, disease activity, colon length, and histology. The study analyzed intestinal proinflammatory cytokines, Th17/Treg cells, and epithelial barrier molecules, along with gut microbiota profiling. RESULTS: ALD-R491 specifically bound vimentin with a dissociation constant (KD) of 328 ± 12.66 nM and no off-target effects. In the DSS model, orally administered ALD-R491 exhibited dose-dependent therapeutic effects, superior to 5-ASA and Tofacitinib. In the IL-10 KO model, ALD-R491 significantly delayed colitis onset and progression, with near-zero disease activity index scores over a 15-week treatment. ALD-R491 consistently showed in both models a reduced proinflammatory cytokine expression, including TNF-α, IL-1ß, IL-6, IL-17, IL-22, a rebalanced Th17/Treg axis by reducing RORγt while enhancing FoxP3 expression, and an improved epithelial barrier integrity by increasing intestinal expressions of Mucin-2, ZO-1 and Claudin5. The intestinal dysbiosis was restored with enriched presence of probiotics. CONCLUSIONS: Targeting vimentin exhibits significant therapeutic effects on various facets of IBD pathogenesis, representing a compelling approach for the development of highly effective treatments in IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Camundongos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo , Citocinas/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/metabolismo , Interleucina-10/metabolismo , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Camundongos Endogâmicos C57BL , Vimentina/metabolismo
3.
Sensors (Basel) ; 23(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37571743

RESUMO

Real-time and accurate bucket pose estimation plays a vital role in improving the intelligence level of mining excavators, as the bucket is a crucial component of the excavator. Existing methods for bucket pose estimation are realized by installing multiple non-visual sensors. However, these sensors suffer from cumulative errors caused by loose connections and short service lives caused by strong vibrations. In this paper, we propose a method for bucket pose estimation based on deep neural network and registration to solve the large registration error problem caused by occlusion. Specifically, we optimize the Point Transformer network for bucket point cloud semantic segmentation, significantly improving the segmentation accuracy. We employ point cloud preprocessing and continuous frame registration to reduce the registration distance and accelerate the Fast Iterative Closest Point algorithm, enabling real-time pose estimation. By achieving precise semantic segmentation and faster registration, we effectively address the problem of intermittent pose estimation caused by occlusion. We collected our own dataset for training and testing, and the experimental results are compared with other relevant studies, validating the accuracy and effectiveness of the proposed method.

4.
Front Microbiol ; 14: 1160821, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37206332

RESUMO

Objective: Bile reflux plays a key role in the development of gastric intestinal metaplasia (GIM), an independent risk factor of gastric cancer. Here, we aimed to explore the biological mechanism of GIM induced by bile reflux in a rat model. Methods: Rats were treated with 2% sodium salicylate and allowed to freely drink 20 mmol/L sodium deoxycholate for 12 weeks, and GIM was confirmed by histopathological analysis. Gastric microbiota was profiled according to the 16S rDNA V3-V4 region, gastric transcriptome was sequenced, and serum bile acids (BAs) were analyzed by targeted metabolomics. Spearman's correlation analysis was used in constructing the network among gastric microbiota, serum BAs, and gene profiles. Real-time polymerase chain reaction (RT-PCR) measured the expression levels of nine genes in the gastric transcriptome. Results: In the stomach, deoxycholic acid (DCA) decreased the microbial diversity but promoted the abundances of several bacterial genera, such as Limosilactobacillus, Burkholderia-Caballeronia-Paraburkholderia, and Rikenellaceae RC9 gut group. Gastric transcriptome showed that the genes enriched in gastric acid secretion were significantly downregulated, whereas the genes enriched in fat digestion and absorption were obviously upregulated in GIM rats. The GIM rats had four promoted serum BAs, namely cholic acid (CA), DCA, taurocholic acid, and taurodeoxycholic acid. Further correlation analysis showed that the Rikenellaceae RC9 gut group was significantly positively correlated with DCA and RGD1311575 (capping protein-inhibiting regulator of actin dynamics), and RGD1311575 was positively correlated with Fabp1 (fatty acid-binding protein, liver), a key gene involved in fat digestion and absorption. Finally, the upregulated expression of Dgat1 (diacylglycerol acyltransferase 1) and Fabp1 related to fat digestion and absorption was identified by RT-PCR and IHC. Conclusion: DCA-induced GIM enhanced gastric fat digestion and absorption function and impaired gastric acid secretion function. The DCA-Rikenellaceae RC9 gut group-RGD1311575/Fabp1 axis might play a key role in the mechanism of bile reflux-related GIM.

5.
Adv Drug Deliv Rev ; 197: 114827, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37068659

RESUMO

In the presence of tissue inflammation, injury, or cancer, myeloid cells are recruited to disease regions through a multi-step process involving myelopoiesis, chemotaxis, cell migration, and diapedesis. As an emerging drug delivery approach, cell-mediated drug delivery takes advantage of the cell recruitment process to enhance the active transport of therapeutic cargo to disease regions. In the past few decades, a variety of nano-engineering methods have emerged to enhance interactions of nanoparticles with cells of interest, which can be adapted for cell-mediated drug delivery. Moreover, the drug delivery field can benefit from the recent clinical success of cell-based therapies, which created cell-engineering methods to engineer circulating leukocytes as 'living drug delivery vehicles' to target diseased tissues. In this review, we first provide an overview of myeloid cell recruitment and discuss how various factors within this process may affect cell-mediated delivery. In the second part of this review article, we summarize the status quo of nano-engineering and cell-engineering approaches and discuss how these engineering approaches can be adapted for cell-mediated delivery. Finally, we discuss future directions of this field, pointing out key challenges in the clinical translation of cell-mediated drug delivery.


Assuntos
Portadores de Fármacos , Nanopartículas , Humanos , Nanomedicina , Sistemas de Liberação de Medicamentos , Células Mieloides , Terapia Baseada em Transplante de Células e Tecidos
6.
Food Res Int ; 164: 112397, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737980

RESUMO

Quinones are highly reactive oxidants and play an essential role in inducing quality deterioration of fruit and vegetable products. Here, a novel stable isotope-labeling approach in combination with high-resolution tandem mass spectrometry UPLC-Q-TOF/MS and UPLC-Q-Exactive Orbitrap/MS, was successfully applied in tracking quinone reaction pathways in both real wines and model reaction systems. Unexpectedly, the binding products of quinone-quinone and quinone-catechol that are not derived from either nucleophilic reaction or redox reaction were discovered and showed the significant high peak area.Self-coupling reactions of semiquinone radicals might provide a possible interpretation for the formation of quinone-quinone products, and a charge transfer reaction coupled with a complementary donor-acceptor interaction is feasibly responsible for the products with a quinone-catechol structure. These findings endow a new perspective for quinone metabolic pathway in foods.


Assuntos
Quinonas , Espectrometria de Massas em Tandem , Quinonas/química , Oxirredução , Catecóis
7.
Food Chem ; 404(Pt A): 134504, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36228474

RESUMO

Non-enzymatic browning is a severe problem in juice industry. Here, polyphenol mediated non-enzymatic browning and its inhibition in apple juice were investigated. Epicatechin (R = -0.83), catechin (CAT, R = -0.79), chlorogenic acid (CGA, R = 0.65) and caffeic acid (CAF, R = 0.65) were strongly correlated with browning. CAT and chlorogenic acid quinone (CGAQ) decreased during storage with the fastest CAT degradation rate (kCGA-enriched = 1.97 × 10-3 mg·L-1·h-1 and kCAT-enriched = 2.09 × 10-3 mg·L-1·h-1) at the initial stage, but CGA and catechin quinone (CATQ) hardly changed. It was possible that CGAQ oxidized CAT at initial stage, leading to the generation of CATQ but less browning. Then the formed CATQ reacted with CAT through the complex reactions, leading to the accumulation of yellow polymers, which might explain why browning increased faster during the secondary and tertiary stages. In addition, glutathione could effectively inhibit browning compared to ascorbic acid and oxygen blocking methods.


Assuntos
Catequina , Malus , Polifenóis , Ácido Clorogênico , Quinonas
8.
J Org Chem ; 87(18): 11979-11988, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36037102

RESUMO

An efficient protocol for the synthesis of furans through Rh(III)-catalyzed vinyl C-H activation from acrylic acids and α-diazocarbonyl compounds has been developed. The reaction features broad functional group tolerance and affords a series of furans in moderate to good yields. Moreover, no additives such as copper or silver salts are required. Some control experiments are performed to give insight into the mechanism of this cascade transformation and the decarbonylation process is involved in the formation of the furan product.

9.
Front Pharmacol ; 13: 858881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814258

RESUMO

Chronic kidney disease (CKD) is often accompanied with imbalanced gut microbiota and impaired intestinal barrier. Hence, efforts to ameliorate renal dysfunction by manipulating gut microbial ecosystem are underway. Yishen Qingli Heluo granule (YQHG) is a representative traditional Chinese medicine (TCM) prescription for clinical treatment of CKD. However, its underlying mechanism has not been well elucidated. This study aimed to explore effects of YQHG on renal dysfunction in 5/6 nephrectomized rats by targeting gut microbiota and intestinal barrier. Here, we found that YQHG provided significant renal protection in 5/6 nephrectomized rats by reducing renal fibrosis and inflammation, reestablishing bacterial communities, and improving intestinal barrier. Our analysis showed that YQHG altered the bacterial community of 5/6 nephrectomized rats. In particular, the prescription significantly increased the relative abundance of SCFA-producing bacteria (i.e., Lactobacillaceae, Lactobacillus and Lactobacillus_gasseri), which was contributed to the improved SCFA concentration (i.e., total SCFA, acetic acid, butyric acid) and intestinal barrier (i.e., the improved permeability and microbial translocation). More critically, microbiota-transfer study showed that the protective effect of YQHG was partly attributed to the mediation of the gut microbiota, especially the SCFA-producing bacteria. Our current findings propose a microbiota-targeted intervention and indicate that YQHG may become a novel promising treatment for CKD.

10.
Drug Des Devel Ther ; 16: 769-787, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355655

RESUMO

Background: Chronic kidney disease (CKD) is considered a global public health problem with high morbidity and mortality. Yishen Qingli Heluo granule (YQHG) is representative traditional Chinese medicine (TCM) remedy for clinical treatment of CKD. This study aims to explore the mechanism of YQHG on CKD through network pharmacology and experimental validation. Methods: Traditional Chinese Medicine Systems Pharmacology (TCMSP) database and wide-scale literature mining were applied to screen active compounds of YQHG. Multiple bioinformatic tools and online databases were applied by us to obtain relevant targets of YQHG and CKD. The intersection targets between YQHG and CKD were considered as candidate targets. The compound-target, herb-candidate target and protein-protein interaction networks were constructed and visualized for topological analyses. GO and KEGG enrichment analyses were conducted to determine the biological processes and signaling pathways. Molecular docking was used to verify the reliability of network pharmacology. Finally, pharmacological evaluation was performed to explore the mechanism of YQHG against CKD on a 5/6 nephrectomy model. Results: Seventy-nine candidate targets, ten core biological processes and one key signaling pathway (p53) were screened. PTGS2 was identified as a key target based on H-CT network. The molecular docking showed that Quercetin, Kaempferol, Luteolin were three key compounds with the best binding activity. In addition, IL6 and Quercetin could form a stable complex with high binding affinity (-7.29 kcal/mol). In vivo experiment revealed that YQHG improved kidney function and fibrosis in 5/6 nephrectomized rats. Moreover, the decreased expression of PTGS2, IL6, and the increased expression of p53 were observed in kidney tissue. Notably, the gut microbiota of rats treated with YQHG was reshaped, which was characterized by a reduced ratio of Firmicutes/Bacteroidota. Conclusion: Our results predicted and verified the potential targets of YQHG on CKD from a holistic perspective, and provided valuable direction for the further research of YQHG.


Assuntos
Farmacologia em Rede , Insuficiência Renal Crônica , Animais , Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Ratos , Insuficiência Renal Crônica/tratamento farmacológico , Reprodutibilidade dos Testes
11.
J Affect Disord ; 304: 122-127, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35219739

RESUMO

PURPOSE: The COVID-19 pandemic has changed the way people live, affecting both their physical and mental health. Adolescents are vulnerable to the stress of the pandemic, and may experience indicators of psychological distress, such as depression. This study aimed to examine the impact of COVID-19-related stressors on depression and the mediating role of life history strategies. METHODS: A two-wave longitudinal study was conducted with 1123 adolescents (51.20% girls, Mage = 14.30) recruited from three junior high schools in the Northeastern province of China. Adolescents' life history strategies, depressive symptoms, and demographic variables were assessed at Time 1 (November 2019) and Time 2 (August 2020), and adolescents' experience of COVID-19-related stressors was assessed at Time 2. None of participants was infected by COVID-19 virus. RESULTS: COVID-19-related stressors were positively associated with depressive symptoms at Time 2 (ß = 0.08, p < 0.01), after controlling for gender, age, SES and depressive symptoms at Time 1. And life history strategies partially mediated the relation of pandemic stress to depression (indirect effect = 0.02, p < 0.05, 95% CI [0.004, 0.034]). There were no gender differences in the relations between stress on depression. LIMITATIONS: The sample was from a district where the pandemic was not very severe, which may limit generalizability of the results. CONCLUSIONS: This study revealed that COVID-19-related stressors may have a long-term impact on adolescents, increasing depression through speeding up their life history strategies. Interventions should focus on life history strategies, particularly cognitive style, among adolescents during and after the pandemic.


Assuntos
COVID-19 , Traços de História de Vida , Adolescente , COVID-19/epidemiologia , China/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pandemias
12.
Biotechniques ; 68(4): 204-210, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32096668

RESUMO

An ultra-high-throughput workflow for next-generation sequencing library construction at nanoliter scale for amplicon sequencing, termed Smartchip Nanowell Platform for Target Enrichment, was established using a nanodispenser system and a nanoliter-scale PCR chip. To demonstrate its cost and time advantages over conventional methods for library construction, quality control and pooling for large-scale samples, target amplicon sequencing of the 16S ribosomal RNA gene V3-V4 region widely used for microbial community profiling was chosen for comparison. The finding of no significant difference in microbial community profiling between the two methods strongly supports the conclusion that Smartchip Nanowell Platform for Target Enrichment is a cost-effective method for next-generation sequencing library construction for large-scale samples to conduct amplicon sequencing-based applications.


Assuntos
DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Microbiota/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Biblioteca Gênica , Nanotecnologia
13.
Biochem Biophys Res Commun ; 461(3): 463-8, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25871795

RESUMO

The off-response of ASH neurons had been overlooked until the microfluidic devices were introduced for in vivo imaging of neuronal activity in Caenorhabditis elegans. The mechanisms of ASH off-response were completely unknown. Here we monitored ASH off-response to CuSO4 stimulation by use of microfluidic device and genetically encoded calcium indicator (GECI) - Case12. We found ASH neurons exhibited a multiphasic response to 10 mM and 50 mM CuSO4 of 30-s stimulation duration. ASH off-responding to Cu(2+) had been dramatically reduced in goa-1, mod-5, trpa-1 and egl-8 mutants. Moreover, in osm-9 mutants ASH off-response was completely eliminated. Neuron-specific rescue of osm-9 in ASH neurons restored the off-response and the normal avoidance behavior in worms.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/efeitos dos fármacos , Canais de Cátion TRPV/fisiologia , Animais , Caenorhabditis elegans/metabolismo , Cálcio/metabolismo , Sulfato de Cobre/farmacologia , Neurônios/metabolismo , Neurônios/fisiologia
14.
Nat Commun ; 6: 5655, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25585042

RESUMO

Sensory modulation is essential for animal sensations, behaviours and survival. Peripheral modulations of nociceptive sensations and aversive behaviours are poorly understood. Here we identify a biased cross-inhibitory neural circuit between ASH and ASI sensory neurons. This inhibition is essential to drive normal adaptive avoidance of a CuSO4 (Cu(2+)) challenge in Caenorhabditis elegans. In the circuit, ASHs respond to Cu(2+) robustly and suppress ASIs via electro-synaptically exciting octopaminergic RIC interneurons, which release octopamine (OA), and neuroendocrinally inhibit ASI by acting on the SER-3 receptor. In addition, ASIs sense Cu(2+) and permit a rapid onset of Cu(2+)-evoked responses in Cu(2+)-sensitive ADF neurons via neuropeptides possibly, to inhibit ASHs. ADFs function as interneurons to mediate ASI inhibition of ASHs by releasing serotonin (5-HT) that binds with the SER-5 receptor on ASHs. This elaborate modulation among sensory neurons via reciprocal inhibition fine-tunes the nociception and avoidance behaviour.


Assuntos
Aprendizagem da Esquiva , Caenorhabditis elegans/fisiologia , Interneurônios/fisiologia , Neurônios/fisiologia , Nociceptividade/fisiologia , Transdução de Sinais/fisiologia , Animais , Comportamento Animal , Fenômenos Biomecânicos , Proteínas de Caenorhabditis elegans/metabolismo , Cálcio/metabolismo , Cobre/química , Sulfato de Cobre/química , Genótipo , Microscopia Confocal , Mutação , Neuropeptídeos/química , Nociceptores/metabolismo , Octopamina/química , Células Receptoras Sensoriais/fisiologia , Serotonina/química
15.
Nat Commun ; 3: 776, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22491324

RESUMO

Feeding behaviour is modulated by both environmental cues and internal physiological states. Appetite is commonly boosted by the pleasant smell (or appearance) of food and destroyed by a bad taste. In reality, animals sense multiple environmental cues at the same time and it is not clear how these sensory inputs are integrated and a decision is made to regulate feeding behaviour accordingly. Here we show that feeding behaviour in Caenorhabditis elegans can be either facilitated by attractive odours or suppressed by repellents. By identifying mutants that are defective for sensory-mediated feeding regulation, we dissected a central flip-flop circuit that integrates two contradictory sensory inputs and generates bistable hormone output to regulate feeding behaviour. As feeding regulation is fundamental to animal survival, we speculate that the basic organizational logic identified here in C. elegans is likely convergent throughout different phyla.


Assuntos
Caenorhabditis elegans/fisiologia , Comportamento Alimentar , Células Receptoras Sensoriais/fisiologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Odorantes/análise , Olfato
16.
Zhong Yao Cai ; 28(12): 1058-9, 2005 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-16568659

RESUMO

To do investigation of flavones from the leaves of Cyclocarya paliums (Batal.) Iljinsk. The pure products were isolated by column chromatography of silica gel, thin layer chromatography of silica gel and column chromatography of Sephadex LH-20, their chemical structures were elucidated by NMR, IR and UV spectroscopic evidence. Four flavones were isolated from the leaves of Cyclocarya paliums. They are quercetin (I), kaempferol (II), kaempferol-7-O-alpha-L-rhamnopyranosyl (III) ,and kaempferol-4'-methoxyl-7-O-beta-D-mancopyranosyl (IV). Compounds III and IV are obtained for the first time from this plants.


Assuntos
Flavonas/química , Juglandaceae/química , Quempferóis/isolamento & purificação , Plantas Medicinais/química , Flavonas/isolamento & purificação , Folhas de Planta/química , Pós , Quercetina/isolamento & purificação
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