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1.
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
2.
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
3.
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.

4.
Nanotechnology ; 35(16)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38154139

RESUMO

Preparing Cd3As2, which is a three-dimensional (3D) Dirac semimetal in certain crystal orientation, on Si is highly desirable as such a sample may well be fully compatible with existing Si CMOS technology. However, there is a dearth of such a study regarding Cd3As2films grown on Si showing the chiral anomaly. Here,for the first time, we report the novel preparation and fabrication technique of a Cd3As2(112) film on a Si (111) substrate with a ZnTe (111) buffer layer which explicitly shows the chiral anomaly with a nontrivial Berry's phase ofπ. Despite the Hall carrier density (n3D≈9.42×1017cm-3) of our Cd3As2film, which is almost beyond the limit for the portents of a 3D Dirac semimetal to emerge, we observe large linear magnetoresistance in a perpendicular magnetic field and negative magnetoresistance in a parallel magnetic field. These results clearly demonstrate the chiral magnetic effect and 3D Dirac semimetallic behavior in our silicon-based Cd3As2film. Our tailoring growth of Cd3As2on a conventional substrate such as Si keeps the sample quality, while also achieving a low carrier concentration.

5.
J Immunol ; 208(8): 1924-1936, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35365563

RESUMO

The germinal center (GC) response is essential for generating memory B and long-lived Ab-secreting plasma cells during the T cell-dependent immune response. In the GC, signals via the BCR and CD40 collaboratively promote the proliferation and positive selection of GC B cells expressing BCRs with high affinities for specific Ags. Although a complex gene transcriptional regulatory network is known to control the GC response, it remains elusive how the positive selection of GC B cells is modulated posttranscriptionally. In this study, we show that methyltransferase like 14 (Mettl14)-mediated methylation of adenosines at the position N 6 of mRNA (N 6-methyladenosine [m6A]) is essential for the GC B cell response in mice. Ablation of Mettl14 in B cells leads to compromised GC B cell proliferation and a defective Ab response. Interestingly, we unravel that Mettl14-mediated m6A regulates the expression of genes critical for positive selection and cell cycle regulation of GC B cells in a Ythdf2-dependent but Myc-independent manner. Furthermore, our study reveals that Mettl14-mediated m6A modification promotes mRNA decay of negative immune regulators, such as Lax1 and Tipe2, to upregulate genes requisite for GC B cell positive selection and proliferation. Thus, our findings suggest that Mettl14-mediated m6A modification plays an essential role in the GC B cell response.


Assuntos
Linfócitos B , Centro Germinativo , Metiltransferases , Adenosina/metabolismo , Animais , Linfócitos B/metabolismo , Linfócitos B/fisiologia , Proliferação de Células , Centro Germinativo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos
6.
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
7.
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
8.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3837-3847, 2024 Jul.
Artigo em Zh | 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
9.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3526-3539, 2024 Jul.
Artigo em Zh | 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
10.
Opt Lett ; 48(21): 5699-5702, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910737

RESUMO

An arithmetic logic unit (ALU) based on the metastructure (MS) with coherent absorption (CA) is proposed in this Letter. The ALU can perform AND and exclusive OR logical operations at the same frequency point. So it can be regarded as an optical half-adder. By controlling the chemical potential of graphene and the phase difference of coherent electromagnetic waves (EWs), two different binary numbers are input into the ALU. The dynamic absorption peaks, which are generated based on the CA, output the outcomes of the carry-digit bit and non-carry sum bit. This ALU can be used in the field of optical processing and encryption, such as processing hamming code. This given ALU based on the MS with CA has major implications for advancing the study and investigation into the application of CA. Furthermore, it also provides a new, to the best of our knowledge, idea for the study of MS with logical operation.

11.
Opt Lett ; 48(10): 2627-2630, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37186725

RESUMO

To date there have been many studies on multi-channel absorbers for conventional photonic crystals (PCs). However, the number of absorption channels is small and uncontrollable, which cannot satisfy applications such as multispectral or quantitative narrowband selective filters. To address these issues, a tunable and controllable multi-channel time-comb absorber (TCA) based on continuous photonic time crystals (PTCs), is theoretically proposed. Compared with conventional PCs with fixed refractive index (RI), this system forms a stronger local electric field enhancement in the TCA by absorbing externally modulated energy, resulting in sharp multi-channel absorption peaks (APs). Tunability can be achieved by adjusting the RI, angle, and time period unit (T) of the PTCs. Diversified tunable methods allow the TCA to have more potential applications. In addition, changing T can adjust the number of multi-channels. More importantly, changing the primary term coefficient of n1(t) of PTC1 can control the number of time-comb absorption peaks (TCAPs) in multi-channels within a certain range, and the mathematical relationship between the coefficients and the number of multiple channels is summarized. This will have potential applications in the design of quantitative narrowband selective filters, thermal radiation detectors, optical detection instruments, etc.

12.
Phys Chem Chem Phys ; 25(20): 14257-14265, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37171203

RESUMO

An advanced optical terahertz (THz) fingerprint sensor based on coherent perfect absorption (CPA) is proposed. Based on a one-dimensional layered photonic structure, the sensor contains a cavity that is developed for THz fingerprint measurement. Utilizing the magneto-optical effect of magnetized InSb, CPA is excited in the structure of the sensor. Taking α-lactose as exemplar material, this numerical simulation is integrated with a Drude-Lorentz model. The transfer matrix method (TMM) is used to calculate the sensitivity (S), linear range (LR), quality (Q), the figure of merit (FOM*), and detection limit (DL) theoretically. Employing the amplitude modulation detection method, the qualitative and quantitative analysis of the α-lactose thickness of 0-0.5 µm could be realized. Because of the fragility of CPA, the S is 0.78255 µm-1, the value of average Q is up to 8019.2, the value of average FOM* is 13 234.4 (THz µm)-1, and the lower DL is 4.21 × 10-6. Moreover, the evolutions of ensemble-averaged absorption in the vicinity of the absorption peaks for different types of disorder effects are considered, which will be considered in the fabrication of sensors.

13.
BMC Surg ; 23(1): 62, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36959589

RESUMO

BACKGROUND: To investigate the risk factors of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP) in patients with biliary tract diseases. METHODS: We retrospectively analyzed the clinical data of 480 patients who underwent ERCP for biliary tract diseases at the Affiliated Zhongshan Hospital of Dalian University from October 2011 to October 2016. The patients were divided into a study group (n = 75, with PEP) and a control group (n = 405, without PEP) based on whether they developed post-ERCP pancreatitis (PEP), and their clinical baseline data and intraoperative conditions were retrieved and compared. Then, factors associated with PEP were analyzed using logistic regression model, based on which a nomogram prediction model was constructed. The receiver operating characteristic (ROC) curve and calibration curve were used to evaluate the performance of the prediction model. RESULTS: Significant differences in age, sex, history of pancreatitis, history of choledocholithiasis, pancreatic duct imaging, pancreatic sphincterotomy, difficult cannulation, multiple cannulation attempts and juxtapapillary duodenal diverticula were observed between the two groups. Multivariate logistic regression analysis showed that age less than 60 years (OR, 0.477; 95% CI, 0.26-0.855), female sex (OR, 2.162; 95% CI, 1.220-3.831), history of pancreatitis (OR, 2.567; 95% CI, 1.218-5.410), history of choledocholithiasis (OR, 2.062; 95% CI, 1.162-3.658), pancreatic sphincterotomy (OR, 2.387; 95% CI, 1.298-4.390), pancreatic duct imaging (OR, 4.429; 95% CI, 1.481-13.242), multiple cannulation attempts (OR, 2.327; 95% CI, 1.205-4.493), difficult cannulation (OR, 2.421; 95% CI, 1.143-5.128), and JPD (OR, 2.002; 95% CI, 1.125-3.564) were independent risk factors for PEP. The nomogram for predicting the occurrence of PEP demonstrated an area under the ROC curve (AUC) of 0.787, and the calibration curves of the model showed good consistency between the predicted and actual probability of PEP. CONCLUSION: Our results showed that age less than 60 years, female sex, history of pancreatitis, history of choledocholithiasis, pancreatic sphincterotomy, pancreatic duct imaging, multiple cannulation attempts, difficult cannulation and juxtapapillary duodenal diverticula were independent risk factors for PEP. In addition, the established nomogram demonstrated promising clinical efficacy in predicting PEP risk in patients who underwent ERCP for biliary tract diseases.


Assuntos
Coledocolitíase , Pancreatite , Humanos , Feminino , Pessoa de Meia-Idade , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Coledocolitíase/cirurgia , Estudos Retrospectivos , Fatores de Risco , Pancreatite/epidemiologia , Pancreatite/etiologia
14.
Angew Chem Int Ed Engl ; 62(40): e202310320, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37582683

RESUMO

Axially chiral N-substituted quinazolinones are important bioactive molecules, which are presented in many synthetic drugs. However, most strategies toward their atroposelective synthesis are mainly limited to the axially chiral arylquinazolinone frameworks. The development of modular synthetic methods to access diverse quinazolinone-based atropisomers remains scarce and challenging. Herein, we report the regio- and atroposelective synthesis of axially chiral N-vinylquinazolinones via the strategy of asymmetric allylic substitution-isomerization. The catalysis system utilized both asymmetric transition-metal catalysis and organocatalysis to efficiently afford trisubstituted and tetrasubstituted N-vinylquinazolinone atropisomers, respectively. With the meticulous design of ß-substituted allylic substrates, both Z- and E-tetrasubstituted axially chiral N-vinylquinazolinones were obtained in good yields and high enantioselectivities.

15.
Anal Chem ; 94(3): 1823-1830, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35020360

RESUMO

Room-temperature ionic liquids (RTILs) emerged as ideal solvents, and bipyridine as one of the most used ligands have been widely employed in surface science, catalysis, and molecular electronics. Herein, in situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) and STM break junction (STM-BJ) technique has been employed to probe the electrochemical process of bipyridine at Au(111)/IL interfaces. It is interestingly found that these molecules undertake a redox process with a pair of well-defined reversible peaks in cyclic voltammograms (CVs). The spectroscopic evidence shows a radical cation generated with rising new Raman peaks related to parallel CC stretching of a positively charged pyridyl ring. Furthermore, these electrochemically charged bipyridine is also confirmed by electrochemical STM-BJ at the single-molecule level, which displays a binary conductance switch ratio of about 400% at the redox potentials. This present work offers a molecular-level insight into the pyridine-mediated reaction process and electron transport in RTILs.

16.
Neurochem Res ; 47(2): 315-326, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34498160

RESUMO

The effects of general anesthetics on the developing brain have aroused much attention in recent years. Sevoflurane, a commonly used inhalation anesthetic especially in pediatric anesthesia, can induce developmental neurotoxicity. In this study, the differentially expressed mRNAs in the hippocampus of newborn rats exposed to 3% sevoflurane for 6 h were detected by RNA-Sequencing. Those data indicated that the mRNA of Klotho was increased after exposure to sevoflurane. Moreover, the protein expression of Klotho was assayed by Western Blot. Besides over-expression and under-expression of Klotho protein, we also detected changes of cell proliferation, ROS, JC-1, and Bcl-2/Bax ratio in PC12 cells exposed to sevoflurane. After exposure to 3% sevoflurane, the expression of Klotho protein increased in the hippocampus of neonatal rats. In PC12 cells, exposure to sevoflurane could increase cellular ROS level, reduce mitochondrial membrane potential and Bcl-2/Bax ratio. While overexpression of Klotho alleviated the above changes, knockdown of Klotho aggravated the injury of sevoflurane. Klotho protein could reduce oxidative stress and mitochondrial injury induced by sevoflurane in the neuron.


Assuntos
Anestésicos Inalatórios , Éteres Metílicos , Anestésicos Inalatórios/toxicidade , Animais , Animais Recém-Nascidos , Apoptose , Hipocampo/metabolismo , Humanos , Éteres Metílicos/toxicidade , Neurônios/metabolismo , Ratos , Sevoflurano/toxicidade
17.
Phytochem Anal ; 33(3): 335-343, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34693578

RESUMO

BACKGROUND: Chenxiang Huaqi tablets (CXHQTs) are a traditional Chinese medicine (TCM) commonly used to treat stomach-related diseases. Currently, the ministerial standards do not provide detailed guidance and regulations on the content determination of CXHQTs, and the reported studies only use individual active components as indicators for determining effective ingredients. OBJECTIVE: The present study aimed to propose a methodology for quality control of CXHQTs based on high-performance liquid chromatography (HPLC) fingerprinting combined with the quantitative analysis of multi-components by single marker (QAMS) method. METHODS: HPLC method was used to determine seven active ingredients and performed fingerprint analysis of CXHQTs. To further process chemometric assessment, technical analysis-model including similarity analysis (SA), hierarchical clustering analysis (HCA), principal components analysis (PCA) and orthogonal partial least squares discrimination analysis (OPLS-DA) was set up to differentiate and classify the 20 batches of samples. RESULTS: After comparing the results of QAMS method with the external standard method (ESM), we found there is no significant difference. Besides, the fingerprint of CXHQT was also established. CONCLUSION: HPLC fingerprint combined with the QAMS could be an efficient and selective analysis technique to achieve a qualitative and quantitative evaluation of executing quality processes.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Controle de Qualidade , Comprimidos
18.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743178

RESUMO

Regulation of food intake is associated with nutrient-sensing systems and the expression of appetite neuropeptides. Nutrient-sensing systems generate the capacity to sense nutrient availability to maintain energy and metabolism homeostasis. Appetite neuropeptides are prominent factors that are essential for regulating the appetite to adapt energy status. However, the link between the expression of appetite neuropeptides and nutrient-sensing systems remains debatable in carnivorous fish. Here, with intracerebroventricular (ICV) administration of six essential amino acids (lysine, methionine, tryptophan, arginine, phenylalanine, or threonine) performed in mandarin fish (Siniperca chuatsi), we found that lysine and methionine are the feeding-stimulating amino acids other than the reported valine, and found a key appetite neuropeptide, neuropeptide Y (NPY), mainly contributes to the regulatory role of the essential amino acids on food intake. With the brain cells of mandarin fish cultured in essential amino acid deleted medium (lysine, methionine, histidine, valine, or leucine), we showed that only lysine deprivation activated the general control nonderepressible 2 (GCN2) signaling pathway, elevated α subunit of eukaryotic translation initiation factor 2 (eIF2α) phosphorylation, increased activating transcription factor 4 (ATF4) protein expression, and finally induced transcription of npy. Furthermore, pharmacological inhibition of GCN2 and eIF2α phosphorylation signaling by GCN2iB or ISRIB, effectively blocked the transcriptional induction of npy in lysine deprivation. Overall, these findings could provide a better understanding of the GCN2 signaling pathway involved in food intake control by amino acids.


Assuntos
Neuropeptídeo Y , Neuropeptídeos , Aminoácidos/metabolismo , Animais , Fator de Iniciação 2 em Eucariotos/metabolismo , Peixes/metabolismo , Lisina , Metionina , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Neuropeptídeos/metabolismo , Transdução de Sinais , Valina
19.
Chin J Traumatol ; 25(6): 400-403, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36180307

RESUMO

Corynespora cassiicola is a common plant pathogen responsible for leaf-spotting diseases in the tropical and subtropical areas. C. cassiicola seldom causes human infections. Here we describe a case of subcutaneous phaeohyphomycosis caused by C. cassiicola in a 76-year-old Chinese man, who presented to our hospital with a purulent discharge and painful sensation on his right leg. Skin biopsy revealed an abscess, and culture confirmed C. cassiicola to be the causative agent. The result was further identified by sequence analysis of the internal transcribed spacer region. The patient was successfully treated with systemic voriconazole and wound debridement: the lesion disappeared after 20 days.


Assuntos
Ascomicetos , Feoifomicose , Masculino , Humanos , Idoso , Feoifomicose/tratamento farmacológico
20.
Zhongguo Zhong Yao Za Zhi ; 47(16): 4462-4468, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046876

RESUMO

An ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method was established for the determination of active components of Sarcandrae Herba, and applied to the pharmacokinetics study of multiple dosage forms. After SD rats were administered by gavage with three dosage forms [Sarcandrae Herba extract, commercial Sarcandrae Herba Guttate Pills, and polydopamine guttate pills loaded with active components of Sarcandrae Herba(PDA-Sg Guttate Pills)], blood samples were collected from the inner canthus at different time points. After protein precipitation, plasma samples were separated on ACQUITY UPLC C_(18) column(2.1 mm×100 mm, 1.7 µm). The mobile phase consisted of water containing 0.2% formic acid and acetonitrile in gradient elution. The negative ions were measured simultaneously in the multi-reaction monitoring(MRM) mode. The pharmacokinetic parameters were calculated and fitted by DAS 2.0. All four components could be detected in the plasma of rats in each group at each time point except the neochlorogenic acid and cryptochlorogenic acid in the Sarcandrae Herba extract group. The guttate pills group showed a significant increase in drug content at each time point. The exposure of the main components of Sarcandrae Herba in blood was effectively increased by PDA-drug loading effect in PDA-Sg Guttate Pills(The AUC_(0-24 h) of neochlorogenic acid, cryptochlorogenic acid, isaziridin and rosmarinic acid reached 2.45, 32.90, 1.54, 4.81 times that of the commercial guttate pills). This study proves the measurability of the above-mentioned multi-component in vitro-in vivo delivery process. The pharmacokinetic study has shown that PDA-Sg Guttate Pills can effectively delay the elimination time and improve the bioavailability of the four components, which can provide theoretical data for the production of the drug.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Indóis , Polímeros , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
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