Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 164
Filtrar
1.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3837-3847, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39099357

RESUMO

The study investigates the therapeutic effects and mechanisms of ginsenoside Rg_1(GRg_1) on sepsis-induced acute lung injury(SALI). A murine model of SALI was created using cecal ligation and puncture(CLP) surgery, and mice were randomly assigned to groups for GRg_1 intervention. Survival and body weight changes were recorded, lung function was assessed with a non-invasive lung function test system, and lung tissue damage was evaluated through HE staining. The content and expression of inflammatory factors were measured by ELISA and qRT-PCR. Apoptosis was examined using flow cytometry and TUNEL staining. The activation and expression of apoptosis-related molecules cysteinyl aspartate specific proteinase 3(caspase-3), B-cell lymphoma-2(Bcl-2), Bcl-2 associated X protein(Bax), and endoplasmic reticulum stress-related molecules protein kinase R-like endoplasmic reticulum kinase(PERK), eukaryotic initiation factor 2α(eIF2α), activating transcription factor 4(ATF4), and C/EBP homologous protein(CHOP) were studied using Western blot and qRT-PCR. In addition, an in vitro model of lipopolysaccharide(LPS)-induced lung alveolar epithelial cell injury was used, with the application of the endoplasmic reticulum stress inducer tunicamycin to validate the action mechanism of GRg_1. RESULTS:: indicated that, when compared to the model group, GRg_1 intervention significantly enhanced the survival time of CLP mice, mitigated body weight loss, and improved impaired lung function indices. The GRg_1-treated mice also displayed reduced lung tissue pathological scores, a reduced lung tissue wet-to-dry weight ratio, and lower protein content in the bronchoalveolar lavage fluid. Serum levels of interleukin-6(IL-6), interleukin-1ß(IL-1ß), and tumor necrosis factor-α(TNF-α), as well as the mRNA expressions of these cytokines in lung tissues, were decreased. There was a notable decrease in the proportion of apopto-tic alveolar epithelial cells, and down-regulated expressions of caspase-3, Bax, PERK, eIF2α, ATF4, and CHOP and up-regulated expression of Bcl-2 were observed. In vitro findings showed that the apoptosis-lowering and apoptosis-related protein down-regulating effects of GRg_1 were significantly inhibited with the co-application of tunicamycin. Altogether, GRg_1 reduces apoptosis of alveolar epithelial cells, inhibits inflammation in the lungs, alleviates lung injury, and enhances lung function, possibly through the PERK/eIF2α/ATF4/CHOP pathway.


Assuntos
Fator 4 Ativador da Transcrição , Lesão Pulmonar Aguda , Células Epiteliais Alveolares , Apoptose , Fator de Iniciação 2 em Eucariotos , Ginsenosídeos , Sepse , Fator de Transcrição CHOP , eIF-2 Quinase , Animais , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/genética , Ginsenosídeos/farmacologia , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , Camundongos , Apoptose/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição CHOP/genética , Sepse/tratamento farmacológico , Sepse/complicações , Sepse/metabolismo , Sepse/genética , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Masculino , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Humanos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Camundongos Endogâmicos C57BL
2.
ACS Appl Mater Interfaces ; 16(32): 43064-43071, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092612

RESUMO

Polymer materials with multiple stimuli-responsive properties have demonstrated many potential and practical applications. By covalently introducing spiropyran (SP1) and spirothiopyran (STP) into the polyurethane backbone, photochromic, mechanochromic, and thermally discolored polymer materials have been prepared. In this work, we report for the first time that white light (violet, blue, and green light) above a certain intensity can activate STP to green color. Based on the above discovery, the polyurethane with SP1 and STP can exhibit reversible three-color changes (brown, green, and purple) in response to four stimuli: ultraviolet irradiation, white light irradiation, mechanical stress, and heat. The color-changing polymer materials have high color contrast and excellent reversibility, and can be used for reversible writing, anticounterfeiting and information encryption, etc.

3.
Adv Sci (Weinh) ; : e2308890, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004913

RESUMO

Interferons (IFNs) activate JAK-STAT pathways to induce downstream effector genes for host defense against invaded pathogens and tumors. Here both type I (ß) and II (γ) IFNs are shown that can activate the transcription factor IRF3 in parallel with STAT1. IRF3-deficiency impairs transcription of a subset of downstream effector genes induced by IFN-ß and IFN-γ. Mechanistically, IFN-induced activation of IRF3 is dependent on the cGAS-STING-TBK1 axis. Both IFN-ß and IFN-γ cause mitochondrial DNA release into the cytosol. In addition, IFNs induce JAK1-mediated tyrosine phosphorylation of cGAS at Y214/Y215, which is essential for its DNA binding activity and signaling. Furthermore, deficiency of cGAS, STING, or IRF3 impairs IFN-ß- or IFN-γ-mediated antiviral and antitumor activities. The findings reveal a novel IRF3 activation pathway parallel with the canonical STAT1/2 activation pathways triggered by IFNs and provide an explanation for the pleiotropic roles of the cGAS-STING-IRF3 axis in host defense.

4.
World J Clin Cases ; 12(18): 3515-3528, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38983402

RESUMO

BACKGROUND: Iron deficiency anemia (IDA) is a prevalent nutritional disorder during pregnancy. Clinical studies indicate that incorporating Chinese patent medicines (CPMs) with oral iron (OI) in treating IDA in pregnancy can reduce adverse effects and improve clinical outcomes. Nonetheless, the comparative efficacy of different CPMs remains unclear. AIM: To assess the safety and effectiveness of different CPMs for treating IDA during pregnancy using network meta-analysis. METHODS: We conducted a search for randomized controlled trials (RCTs) that combined CPM and OI for IDA treatment in pregnancy, spanning from 2013 to the present. Data analysis was performed using Rev Man 5.3 and Stata 14.0 on literature that satisfied the quality criteria. RESULTS: The analysis included 45 RCTs, encompassing 4422 pregnant patients with IDA. Six CPMs were examined, including Shengxuebao Mixture, Shengxuening Tablets (SXN), Yiqi Weixue CPMs (YQWX), Jianpi Shengxue CPMs (JPSX), Yiqi Buxue Tablets, and Compound Hongyi Buxue Oral Liquid (FFHY). Findings indicated that FFHY + OI significantly improved the clinical effective rate. SXN + OI was most effective in boosting red blood cells counts and hemoglobin levels. YQWX + OI showed superior results in improving serum ferritin, and SXN + OI was most effective in increasing serum iron levels. JPSX + OI was optimal in reducing adverse pregnancy outcomes, while YQBX + OI effectively minimized adverse events. A cluster analysis suggested that SXN + OI could be the potentially optimal therapeutic regimen for IDA in pregnancy. CONCLUSION: This study demonstrates that the combination of OI with CPMs offers better outcomes than OI alone. Based on clinical efficacy and other measured outcomes, SXN + OI emerges as the most effective treatment modality for improving the health of pregnant patients with IDA.

5.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3526-3539, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39041124

RESUMO

The method of ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry(UHPLC-Q/Orbitrap HRMS)combined with molecular network was developed in this study for rapidly analyzing the chemical components of the Qinggu San reference sample of classical prescription. Firstly, an ACQUITY UPLC BEH Shield RP_(18) column(2.1 mm×100 mm, 1.7 µm)was used, and acetonitrile and 0.1% formic acid were taken as the mobile phases for gradient elution. The flow rate was 0.4 mL·min~(-1), and the column temperature was 30 ℃. Under these conditions, the mass spectrum data were collected in both positive and negative ion modes of the heated electrospray ionization source. Subsequently, the mass spectrum data of the Qinggu San reference sample were uploaded to the Global Natural Products Social Molecular Network(GNPS)platform for calculation and analysis, and a visual molecular network was built with Cytoscape 3.8.2 software. On this basis, the chemical components of the Qinggu San reference sample were identified by fragmentation regularity of standard compounds, retention time, accurate relative molecular weight of HR-MS, characteristic fragment ions information, literature, and databases. Finally, a total of 105 chemical components were identified and speculated in the Qinggu San reference sample, including 19 iridoid glycosides, 23 flavonoids, 15 phenylpropanoids, 11 triterpene saponins, and 37 other components. Meanwhile, two of these components are potential new compounds. The method used in this study not only achieved rapid and accurate identification of chemical components in the Qinggu San reference sample and provided a scie-ntific basis for the study of pharmacological substances and quality control of Qinggu San compound preparations but also provided a refe-rence for the rapid identification of chemical components in traditional Chinese medicine compound preparations.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Espectrometria de Massas/métodos
6.
New Phytol ; 243(6): 2401-2415, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39073209

RESUMO

Mycorrhizal associations are key mutualisms that shape the structure of forest communities and multiple ecosystem functions. However, we lack a framework for predicting the varying dominance of distinct mycorrhizal associations in an integrated proxy of multifunctionality across ecosystems. Here, we used the datasets containing diversity of mycorrhizal associations and 18 ecosystem processes related to supporting, provisioning, and regulating services to examine how the dominance of ectomycorrhiza (EcM) associations affects ecosystem multifunctionality in subtropical mountain forests in Southwest China. Meanwhile, we synthesized the prevalence of EcM-dominant effects on ecosystem functioning in forest biomes. Our results demonstrated that elevation significantly modified the distributions of EcM trees and fungal dominance, which in turn influenced multiple functions simultaneously. Multifunctionality increased with increasing proportion of EcM associations, supporting the ectomycorrhizal-dominance hypothesis. Meanwhile, we observed that the impacts of EcM dominance on individual ecosystem functions exhibited different relationships among forest biomes. Our findings highlight the importance of ectomycorrhizal dominance in regulating multifunctionality in subtropical forests. However, this ectomycorrhizal feedback in shaping ecosystem functions cannot necessarily be generalized across forests. Therefore, we argue that the predictions for ecosystem multifunctionality in response to the shifts of mycorrhizal composition could vary across space and time.


Assuntos
Florestas , Micorrizas , Micorrizas/fisiologia , Clima Tropical , China , Ecossistema , Modelos Biológicos , Árvores/microbiologia , Árvores/fisiologia , Biodiversidade , Altitude
7.
Huan Jing Ke Xue ; 45(6): 3638-3648, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897783

RESUMO

To achieve efficient resource utilization of fly ash and multi-source organic waste, a composting experiment was carried out to investigate the effects of fly ash on co-aerobic composting using kitchens, chicken manure, and sawdust (15:5:2). The effects of different application doses (5 % and 10 %, calculated in total wet weight of organic solid waste) of fly ash on physical and chemical properties, nutrient elements, and bacterial community structure during co-composting were evaluated. The results showed that the addition dose of 5 % and 10 % fly ash significantly increased the highest temperature (56.6 ℃ and 56.9 ℃) and extended the thermophilic period to nine days. Compared with that in the control, the total nutrient content of compost products in the treatments of 5 % FA and 10 % FA was increased by 4.09 % and 13.55 %, respectively. The bacterial community structure changed greatly throughout the composting, and the bacterial diversity of all treatments increased obviously. In the initial stage of composting, Proteobacteria was the dominant phylum of bacteria, with a relative abundance ranging from 35.26 % to 39.40 %. In the thermophilic period, Firmicutes dominated; its relative abundance peaked at 52.46 % in the 5 % FA treatment and 67.72 % in the 10 % FA treatment. Bacillus and Thermobifida were the predominant groups in the thermophilic period of composting. The relative abundance of Bacillus and Thermobifida in the 5 % FA and 10 % FA treatments were 33.41 % and 62.89 %(Bacillus) and 33.06 % and 12.23 %(Thermobifida), respectively. The results of the redundancy analysis (RDA) revealed that different physicochemical indicators had varying degrees of influence on bacteria, with organic matter, pH, available phosphorus, and available potassium being the main environmental factors influencing bacterial community structure. In summary, the addition of fly ash promoted the harmlessness and maturation of co- aerobic composting of urban multi-source organic waste, while optimizing microbial community structure and improving the quality and efficiency of composting.


Assuntos
Bactérias , Cidades , Cinza de Carvão , Compostagem , Compostos Orgânicos , Eliminação de Resíduos , Resíduos Sólidos , Compostagem/métodos , Eliminação de Resíduos/métodos , Compostos Orgânicos/análise , Resíduos Sólidos/análise , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Esterco , Proteobactérias , Microbiota
8.
J Med Chem ; 67(12): 9869-9895, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38888047

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease. Targeting NLRP3 inflammasome, specifically its interaction with NEK7 via the LRR domain of NLRP3, is a promising therapeutic strategy. Our research aimed to disrupt this interaction by focusing on the LRR domain. Through virtual screening, we identified five compounds with potent anti-inflammatory effects and ideal LRR binding affinity. Lead compound C878-1943 underwent structural optimization, yielding pyridoimidazole derivatives with different anti-inflammatory activities. Compound I-19 from the initial series effectively inhibited caspase-1 and IL-1ß release in an adjuvant-induced arthritis (AIA) rat model, significantly reducing joint swelling and spleen/thymus indices. To further enhance potency and extend in vivo half-life, a second series including II-8 was developed, demonstrating superior efficacy and longer half-life. Both I-19 and II-8 bind to the LRR domain, inhibiting NLRP3 inflammasome activation. These findings introduce novel small molecule inhibitors targeting the LRR domain of NLRP3 protein and disrupt NLRP3-NEK7 interaction, offering a novel approach for RA treatment.


Assuntos
Artrite Experimental , Artrite Reumatoide , Quinases Relacionadas a NIMA , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Quinases Relacionadas a NIMA/antagonistas & inibidores , Quinases Relacionadas a NIMA/metabolismo , Animais , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Humanos , Ratos , Artrite Experimental/tratamento farmacológico , Descoberta de Drogas , Relação Estrutura-Atividade , Masculino , Inflamassomos/metabolismo , Inflamassomos/antagonistas & inibidores , Simulação de Acoplamento Molecular , Antirreumáticos/farmacologia , Antirreumáticos/química , Antirreumáticos/síntese química , Antirreumáticos/uso terapêutico
9.
Sci Total Environ ; 935: 173343, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777069

RESUMO

Niche convergence or conservatism have been proposed as essential mechanisms underlying elevational plant community assembly in tropical mountain ecosystems. Subtropical mountains, compared to tropical mountains, are likely to be shaped by a mixing of different geographic affinities of species and remain somehow unclear. Here, we used 31 0.1-ha permanent plots distributed in subtropical forests on the eastern and western aspects of the Gaoligong Mountains, southwest China between 1498 m and 3204 m a.sl. to evaluate how niche-based and biogeographic processes shape tree community assembly along elevational gradients. We analyzed the elevational patterns of taxonomic, phylogenetic and functional diversity, as well as of individual traits, and assessed the relative importance of environmental effects on these diversity measures. We then classified tree species as being either tropical affiliated or temperate affiliated and estimated their contribution to the composition of biogeographic affinities. Species richness decreased with elevation, and species composition showed apparent turnover across the aspects and elevations. Most traits exhibited convergent patterns across the entire elevational gradient. Phylogenetic and functional diversity showed opposing patterns, with phylogenetic diversity increasing and functional diversity decreasing with elevation. Soil nutrients, especially phosphorus and nitrogen, appeared to be the main abiotic variables driving the elevational diversity patterns. Communities at lower elevations were occupied by tropical genera, while highlands contained species of tropical and temperate biogeographic affinities. Moreover, the high phylogenetic diversity at high elevations were likely due to differences in evolutionary history between temperate and tropical species. Our results highlight the importance of niche convergence of tropical species and the legacy of biogeographic history on the composition and structure of subtropical mountain forests. Furthermore, limited soil phosphorus caused traits divergence and the partitioning for different forms of phosphorus may explain the high biodiversity found in phosphorus-limited subtropical forests.


Assuntos
Altitude , Biodiversidade , Florestas , Árvores , China , Filogenia , Ecossistema , Clima Tropical
10.
J Hazard Mater ; 472: 134499, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38759282

RESUMO

Cl- activated peroxymonosulfate (PMS) oxidation technology can effectively degrade pollutants, but the generation of chlorinated disinfection byproducts (DBPs) limits the application of this technology in water treatment. In this study, a method of nanobubbles (NBs) synergistic Cl-/PMS system was designed to try to improve this technology. The results showed the synergistic effects of NBs/Cl-/PMS were significant and universal while its upgrade rate was from 12.89% to 34.97%. Moreover, the synergistic effects can be further improved by increasing the concentration and Zeta potential of NBs. The main synergistic effects of NBs/Cl-/PMS system were due to the electrostatic attraction of negatively charged NBs to Na+ from NaCl, K+ from PMS, and H+ from phenol, which acted as a "bridge" between Cl- and HSO5- as well as phenol and Cl-/HSO5-, increasing active substance concentration. In addition, the addition of NBs completely changed the oxidation system of Cl-/PMS from one that increases environmental toxicity to one that reduces it. The reason was that the electrostatic attraction of NBs changed the active sites and degradation pathway of phenol, greatly reducing the production of highly toxic DBPs. This study developed a novel environmentally friendly oxidation technology, which provides an effective strategy to reduce the generation of DBPs in the Cl-/PMS system.

11.
Int J Cancer ; 155(4): 697-709, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577882

RESUMO

Patient-derived organoids (PDOs) may facilitate treatment selection. This retrospective cohort study evaluated the feasibility and clinical benefit of using PDOs to guide personalized treatment in metastatic breast cancer (MBC). Patients diagnosed with MBC were recruited between January 2019 and August 2022. PDOs were established and the efficacy of customized drug panels was determined by measuring cell mortality after drug exposure. Patients receiving organoid-guided treatment (OGT) were matched 1:2 by nearest neighbor propensity scores with patients receiving treatment of physician's choice (TPC). The primary outcome was progression-free survival. Secondary outcomes included objective response rate and disease control rate. Targeted gene sequencing and pathway enrichment analysis were performed. Forty-six PDOs (46 of 51, 90.2%) were generated from 45 MBC patients. PDO drug screening showed an accuracy of 78.4% (95% CI 64.9%-91.9%) in predicting clinical responses. Thirty-six OGT patients were matched to 69 TPC patients. OGT was associated with prolonged median progression-free survival (11.0 months vs. 5.0 months; hazard ratio 0.53 [95% CI 0.33-0.85]; p = .01) and improved disease control (88.9% vs. 63.8%; odd ratio 4.26 [1.44-18.62]) compared with TPC. The objective response rate of both groups was similar. Pathway enrichment analysis in hormone receptor-positive, human epidermal growth factor receptor 2-negative patients demonstrated differentially modulated pathways implicated in DNA repair and transcriptional regulation in those with reduced response to capecitabine/gemcitabine, and pathways associated with cell cycle regulation in those with reduced response to palbociclib. Our study shows that PDO-based functional precision medicine is a feasible and effective strategy for MBC treatment optimization and customization.


Assuntos
Neoplasias da Mama , Organoides , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Organoides/patologia , Organoides/efeitos dos fármacos , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Adulto , Medicina de Precisão/métodos , Intervalo Livre de Progressão , Metástase Neoplásica , Piridinas/uso terapêutico , Piridinas/administração & dosagem , Piperazinas/uso terapêutico , Piperazinas/administração & dosagem , Resultado do Tratamento
12.
Acta Pharmacol Sin ; 45(9): 1879-1897, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38689095

RESUMO

Endothelial senescence, aging-related inflammation, and mitochondrial dysfunction are prominent features of vascular aging and contribute to the development of aging-associated vascular disease. Accumulating evidence indicates that DNA damage occurs in aging vascular cells, especially in endothelial cells (ECs). However, the mechanism of EC senescence has not been completely elucidated, and so far, there is no specific drug in the clinic to treat EC senescence and vascular aging. Here we show that various aging stimuli induce nuclear DNA and mitochondrial damage in ECs, thus facilitating the release of cytoplasmic free DNA (cfDNA), which activates the DNA-sensing adapter protein STING. STING activation led to a senescence-associated secretory phenotype (SASP), thereby releasing pro-aging cytokines and cfDNA to further exacerbate mitochondrial damage and EC senescence, thus forming a vicious circle, all of which can be suppressed by STING knockdown or inhibition. Using next-generation RNA sequencing, we demonstrate that STING activation stimulates, whereas STING inhibition disrupts pathways associated with cell senescence and SASP. In vivo studies unravel that endothelial-specific Sting deficiency alleviates aging-related endothelial inflammation and mitochondrial dysfunction and prevents the development of atherosclerosis in mice. By screening FDA-approved vasoprotective drugs, we identified Cilostazol as a new STING inhibitor that attenuates aging-related endothelial inflammation both in vitro and in vivo. We demonstrated that Cilostazol significantly inhibited STING translocation from the ER to the Golgi apparatus during STING activation by targeting S162 and S243 residues of STING. These results disclose the deleterious effects of a cfDNA-STING-SASP-cfDNA vicious circle on EC senescence and atherogenesis and suggest that the STING pathway is a promising therapeutic target for vascular aging-related diseases. A proposed model illustrates the central role of STING in mediating a vicious circle of cfDNA-STING-SASP-cfDNA to aggravate age-related endothelial inflammation and mitochondrial damage.


Assuntos
Senescência Celular , Cilostazol , Inflamação , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Mitocôndrias , Animais , Proteínas de Membrana/metabolismo , Cilostazol/farmacologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Senescência Celular/efeitos dos fármacos , Camundongos , Envelhecimento/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Citosol/metabolismo , DNA/metabolismo , Masculino , Células Endoteliais da Veia Umbilical Humana , Fenótipo Secretor Associado à Senescência , Células Cultivadas
13.
Nat Commun ; 15(1): 3254, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627395

RESUMO

The past century has witnessed a large number of reports on the Z/E isomerization of alkenes. However, the vast majority of them are still limited to the isomerization of di- and tri-substituted alkenes. The stereospecific Z/E isomerization of tetrasubstituted alkenes remains to be an underdeveloped area, thus lacking in a stereodivergent synthesis of axially chiral alkenes. Herein we report the atroposelective synthesis of tetrasubstituted alkene analogues by asymmetric allylic substitution-isomerization, followed by their Z/E isomerization via triplet energy transfer photocatalysis. In this regard, the stereodivergent synthesis of axially chiral N-vinylquinolinones is achieved efficiently. Mechanistic studies indicate that the benzylic radical generation and distribution are two key factors for preserving the enantioselectivities of axially chiral compounds.

14.
J Med Chem ; 67(9): 7635-7646, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38661304

RESUMO

The T-cell receptor (TCR) is a crucial molecule in cellular immunity. The single-chain T-cell receptor (scTCR) is a potential format in TCR therapeutics because it eliminates the possibility of αß-TCR mispairing. However, its poor stability and solubility impede the in vitro study and manufacturing of therapeutic applications. In this study, some conserved structural motifs are identified in variable domains regardless of germlines and species. Theoretical analysis helps to identify those unfavored factors and leads to a general strategy for stabilizing scTCRs by substituting residues at exact IMGT positions with beneficial propensities on the consensus sequence of germlines. Several representative scTCRs are displayed to achieve stability optimization and retain comparable binding affinities with the corresponding αß-TCRs in the range of µM to pM. These results demonstrate that our strategies for scTCR engineering are capable of providing the affinity-enhanced and specificity-retained format, which are of great value in facilitating the development of TCR-related therapeutics.


Assuntos
Receptores de Antígenos de Linfócitos T , Humanos , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Estabilidade Proteica , Receptores de Antígenos de Linfócitos T alfa-beta/química , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Sequência de Aminoácidos , Modelos Moleculares , Engenharia de Proteínas , Ligação Proteica
15.
Front Pharmacol ; 15: 1348076, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572428

RESUMO

Cancer stands as a prominent global cause of death. One of the key reasons why clinical tumor chemotherapy fails is multidrug resistance (MDR). In recent decades, accumulated studies have shown how Natural Product-Derived Compounds can reverse tumor MDR. Discovering novel potential modulators to reduce tumor MDR by Natural Product-Derived Compounds has become a popular research area across the globe. Numerous studies mainly focus on natural products including flavonoids, alkaloids, terpenoids, polyphenols and coumarins for their MDR modulatory activity. Natural products reverse MDR by regulating signaling pathways or the relevant expressed protein or gene. Here we perform a deep review of the previous achievements, recent advances in the development of natural products as a treatment for MDR. This review aims to provide some insights for the study of multidrug resistance of natural products.

16.
Genes Dis ; 11(4): 101101, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38560497

RESUMO

Obesity-related glomerulopathy (ORG) is an independent risk factor for chronic kidney disease and even progression to end-stage renal disease. Efforts have been undertaken to elucidate the mechanisms underlying the development of ORG and substantial advances have been made in the treatment of ORG, but relatively little is known about cell-specific changes in gene expression. To define the transcriptomic landscape at single-cell resolution, we analyzed kidney samples from four patients with ORG and three obese control subjects without kidney disease using single-cell RNA sequencing. We report for the first time that immune cells, including T cells and B cells, are decreased in ORG patients. Further analysis indicated that SPP1 was significantly up-regulated in T cells and B cells. This gene is related to inflammation and cell proliferation. Analysis of differential gene expression in glomerular cells (endothelial cells, mesangial cells, and podocytes) showed that these cell types were mainly enriched in genes related to oxidative phosphorylation, cell adhesion, thermogenesis, and inflammatory pathways (PI3K-Akt signaling, MAPK signaling). Furthermore, we found that the podocytes of ORG patients were enriched in genes related to the fluid shear stress pathway. Moreover, an evaluation of cell-cell communications revealed that there were interactions between glomerular parietal epithelial cells and other cells in ORG patients, with major interactions between parietal epithelial cells and podocytes. Altogether, our identification of molecular events, cell types, and differentially expressed genes may facilitate the development of new preventive or therapeutic approaches for ORG.

17.
Sci Rep ; 14(1): 5093, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429326

RESUMO

With the continuous construction of urban traffic roads, more and more new roads are cut off by existing roads to form "dead end roads". There is an urgent need for a trenchless method suitable for urban ultra-shallow overburden to build the undercrossing tunnel. To solve this problem, this paper proposed the micro pipe jacking and joint assembly structure (MPJ & JAS) method, which has the characteristics of shallow burial depth, low cost, short construction time, flexible cross-section setting and high space utilization. The MPJ & JAS method construct a large cross-section tunnel through assembling small cross-section elements, quite different from traditional methods. Therefore, this paper designed a CT-shaped integrated joint, the mechanical performance of which was verified and clarified by tensile test. The bending test and finite element (FE) analysis proved the reliability of MPJ & JAS tunnel structure, and confirmed the structure performances such as the failure models, crack behaviors, load-deflection response and stress-strain distribution. Moreover, the influences of the steel plate thickness, concrete strength and shear connector spacing were determined by the FE analysis. On the basis of test results and reasonable assumptions, a theoretical design method considering the influence of the CT-shaped integrated joint was proposed, which can effectively predict the bending strength of the MPJ & JAS tunnel structure with an error of less than 10%. Finally, in view of the characteristics of the MPJ & JAS method, the suitable micro pipe jacking machine, soil reinforcement measure, hydraulic traction construction technology, high-precision guidance system and concrete construction quality detection method based on the phased array ultrasonic imaging technology were developed, supporting the accurate and efficient construction of the MPJ & JAS tunnel.

18.
Sci Total Environ ; 922: 171201, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38417506

RESUMO

Mycelial pellets formed by Penicillium thomii ZJJ were applied as efficient biosorbents for the removal of polycyclic aromatic hydrocarbons (PAHs), which are a type of ubiquitous harmful hydrophobic pollutants. The live mycelial pellets were able to remove 93.48 % of pyrene at a concentration of 100 mg/L within 48 h, demonstrating a maximum adsorption capacity of 285.63 mg/g. Meanwhile, the heat-killed one also achieved a removal rate of 65.01 %. Among the six typical PAHs (pyrene, phenanthrene, fluorene, anthracene, fluoranthene, benzo[a]pyrene), the mycelial pellets preferentially adsorbed the high molecular weight PAHs, which also have higher toxicity, resulting in higher removal efficiency. The experimental results showed that the biosorption of mycelial pellets was mainly a spontaneous physical adsorption process that occurred as a monolayer on a homogeneous surface, with mass transfer being the key rate-limiting step. The main adsorption sites on the surface of mycelia were carboxyl and N-containing groups. Extracellular polymeric substances (EPS) produced by mycelial pellets could enhance adsorption, and its coupling with dead mycelia could achieve basically the same removal effect to that of living one. It can be concluded that biosorption by mycelial pellets occurred due to the influence of electrostatic and hydrophobic interactions, consisting of five steps. Furthermore, the potential applicability of mycelial pellets has been investigated considering diverse factors. The mycelia showed high environmental tolerance, which could effectively remove pyrene across a wide range of pH and salt concentration. And pellets diameters and humic acid concentration had a significant effect on microbial adsorption effect. Based on a cost-effectiveness analysis, mycelium pellets were found to be a low-cost adsorbent. The research outcomes facilitate a thorough comprehension of the adsorption process of pyrene by mycelial pellets and their relevant applications, proposing a cost-effective method without potential environmental issues (heat-killed mycelial pellets plus EPS) to removal PAHs.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Adsorção , Pirenos , Micélio
19.
Opt Lett ; 49(3): 415-417, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300033

RESUMO

We present a corrigendum to our Letter [Opt. Lett.48, 5699 (2023)10.1364/OL.505761]. In section 3 of the original supplementary material, the absolute value is incorrectly taken in resolving the Kubo formula for describing the conductivity of graphene. Because this is a mistake with the conductivity of graphene, the coupling of the original structure is broken when the correct result is inserted into the code of the transfer matrix. So, the structure of the arithmetic logic unit (ALU), characteristic frequency point, and phase control have been modified accordingly. However, the ultimate function and the conclusion of this work remain unchanged.

20.
Phys Chem Chem Phys ; 26(5): 4447-4454, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38240154

RESUMO

A one-dimensional optical biosensing metastructure (OBM) with graphene layers is presented in this paper. It is realized by coherent perfect absorption (CPA) and operates in the transverse electric mode. It shows a strong linear fitting relationship between the refractive index (RI) of the analysis layer and the frequency corresponding to the absorption peak, and the R-square is up to 1. Additionally, based on the principle of CPA, the OBM can realize the function of multiple cancer cell detection by adjusting the detection range by controlling the phase difference of coherent electromagnetic waves. Its detection ranges are 1.34-1.355 and 1.658-1.662. Thanks to its high-quality factor, great figure of merit, and low detection limit, whose best values are, respectively, 6.9 × 104, 1.2 × 104 RIU-1, and 3.6 × 10-6 RIU, the detection of weak changes in the RI of a cancer cell is possible. Additionally, its sensitivity can reach 26.57 THz RIU-1. This OBM based on CPA has major implications for advancing the study and investigation into the application of CPA. It also provides a simple and efficient approach to distinguish cancer cells and may be widely used in the biomedical field.


Assuntos
Grafite , Neoplasias , Humanos , Eletricidade , Neoplasias/diagnóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA