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1.
J Org Chem ; 89(5): 3597-3604, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38356389

RESUMO

A very mild and efficient procedure has been developed for the preparation of N-methylated uridine, pseudouridine, guanosine and inosine derivatives. This process was compatible with free hydroxyls within the ribose and did not require precautions on the protection or deprotection of other functionalities. The key to this extremely mild methylation without protection relied on the in situ generated methyl oxonium from the Wittig reagent and methanol. A putative mechanism for the selective methylation was also proposed.

2.
J Mol Recognit ; 36(8): e3046, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37455320

RESUMO

As a natural carrier protein, zein was intensively studied for the construction of a flavonoid delivery system. Chrysin has presented superior tumor-resistant, anti-inflammatory, and anti-oxidation potentials among the flavonoid candidates in clinical practice. However, due to inadequate research, the binding mechanism and structural affinity of zein to chrysin are still indeterminate. Therefore, multispectral methods were employed to explore the molecular interaction of zein and chrysin in this work. These techniques showed that chrysin reduced the intrinsic fluorescence of zein via a static process and that the interaction between zein and chrysin was mainly driven spontaneously by hydrophobic forces. Additionally, the experimental results revealed the changed microenvironment in the vicinity of tyrosine and affected secondary structure in the presence of chrysin, indicating zein's conformation were altered by chrysin. This work provided comprehensive insight into the combination of plant-derived protein (zein) and flavonoids (chrysin) and helped rationalize the protection, transportation, and release of chrysin through a zein-based delivery system.


Assuntos
Zeína , Zeína/química , Flavonoides/química
3.
Phys Rev Lett ; 131(3): 031601, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540874

RESUMO

Conformal field theory (CFT) plays a crucial role in the study of various critical phenomena. While much attention has been paid to the critical exponents of different universalities, which correspond to the conformal dimensions of CFT primary fields, other important and intricate data such as operator product expansion (OPE) coefficients governing the fusion of two primary fields, have remained largely unexplored, especially in dimensions higher than 2D (or equivalently, 1+1D). Motivated by the recently proposed fuzzy sphere regularization, we investigate the operator content of 3D Ising criticality from a microscopic perspective. We first outline the procedure for extracting OPE coefficients on the fuzzy sphere and then compute 13 OPE coefficients of low-lying CFT primary fields. Our results are highly accurate and in agreement with the numerical conformal bootstrap data of 3D Ising CFT. Moreover, we were able to obtain 4 OPE coefficients, including f_{T_{µν}T_{ρη}ε}, which were previously unknown, thus demonstrating the superior capabilities of our scheme. Expanding the horizon of the fuzzy sphere regularization from the state perspective to the operator perspective opens up new avenues for exploring a wealth of new physics.

4.
Cardiology ; 148(6): 581-592, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37459844

RESUMO

BACKGROUND: Left atrial appendage closure (LAAC) is a safe and effective method for preventing embolic events in patients with non-valvular atrial fibrillation. However, peri-device leaks (PDLs) are sometimes unavoidable. Controversy exists regarding whether PDLs lead to embolic events. OBJECTIVES: This study aimed to explore the association between PDLs and embolic events, including ischaemic stroke, transient ischaemic attacks (TIAs), and systemic embolism (SE). METHODS: We conducted a systematic search of the PubMed, Web of Science, MEDLINE, and Cochrane Library databases for studies published up to September 25, 2022, to compare the rate of ischaemic stroke/TIA/SE between the PDL group and the non-PDL group after LAAC. RESULTS: Thirteen studies comprising 54,405 patients were included in the meta-analysis. The PDL group detected by transoesophageal echocardiography (TEE) had a significantly higher rate of ischaemic stroke/TIA/SE than the non-PDL group (OR: 1.20, 95% CI: 1.08-1.33, p = 0.0009). However, no difference in ischaemic stroke/TIA/SE was found between the PDL and non-PDL subgroups of the cardiac computed tomography angiography (CCTA) group (OR: 1.12, 95% CI: 0.51-2.50, p = 0.77). CCTA and TEE showed different rates of PDL detection, with the CCTA group having a higher rate of PDL detection (p < 0.0001), especially for trivial leaks. CONCLUSIONS: PDL detected by TEE increases the risk of embolic events after LAAC. However, no association was found between PDL and ischaemic stroke/TIA/SE in the CCTA group, which showed a higher rate of PDL detection than TEE, particularly for trivial leaks. In the future, CCTA may be used to explore the relationship between PDL size and ischaemic stroke/TIA/SE.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Isquemia Encefálica , Embolia , Ataque Isquêmico Transitório , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Ataque Isquêmico Transitório/etiologia , Oclusão do Apêndice Atrial Esquerdo , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Isquemia Encefálica/etiologia , Fibrilação Atrial/etiologia , AVC Isquêmico/etiologia , Embolia/etiologia , Embolia/prevenção & controle , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Resultado do Tratamento , Ecocardiografia Transesofagiana , Cateterismo Cardíaco/efeitos adversos
5.
Sensors (Basel) ; 23(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37960523

RESUMO

Aiming at the problem of the low cooperative positioning accuracy and robustness of multi-UAV formation, a cooperative positioning method of a multi-UAV based on an adaptive fault-tolerant federated filter is proposed. Combined with the position of the follower UAV and leader UAV, and the relative range between them, a cooperative positioning model of the follower UAV is established. On this basis, an adaptive fault-tolerant federated filter is designed. Fault detection and isolation technology are added to improve the positioning accuracy of the follower UAV and the fault tolerance performance of the filter. Meanwhile, the measurement noise matrix is adjusted by the adaptive information allocation coefficient to reduce the impact of undetected fault information on the sub-filter and global estimation accuracy. The simulation results show that the adaptive fault-tolerant federated algorithm can greatly improve the positioning accuracy, which is 83.4% higher than that of the absolute positioning accuracy of a single UAV. In the case of a gradual fault, the method has a stronger fault-tolerant performance and reconstruction performance.

6.
J Sci Food Agric ; 103(1): 118-124, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35811466

RESUMO

BACKGROUND: Quinoa is a good gluten-free resource for food processing, especially bread making, and can improve and prevent the development of complications associated with celiac disease (CD). However, lack of gluten affects quinoa bread quality. Previous research showed that soy protein isolate (SPI) could improve gluten-free bread quality to some extent. Therefore, this study investigated the effects of SPI on the physical properties of quinoa dough and gluten-free bread quality characteristics. RESULTS: Results showed that, with appropriate SPI substitution, the farinograph properties of quinoa flour significantly improved (P < 0.05). The sample with 8% SPI substitution showed a better development time (DT, 3.30 ± 0.20 min), stability time (ST, 8.80 ± 0.10 min) and softening degree (SD, 8.80 ± 0.10 FU), which were close to those of wheat flour, although more water absorption (WA, 76.40 ± 2.10%) was needed than for wheat flour (66.30 ± 3.10%). The extensograph properties of quinoa flour also significantly improved after 8% SPI substitution (P < 0.05). Furthermore, SPI substitution increased G' moduli of quinoa dough and decreased tan δ to some extent, providing better rheological properties closer to those of wheat dough. SPI substitution also improved the quality and texture of quinoa bread and reduced the gap with wheat bread. When SPI substitution was 8%, the specific volume, hardness and springiness of quinoa bread were 2.29 ± 0.05 mL g-1 , 1496.47 ± 85.21 g and 0.71 ± 0.03%, respectively. CONCLUSION: These results suggested that SPI substitution would be an effective way to develop higher-quality gluten-free bread. © 2022 Society of Chemical Industry.


Assuntos
Pão , Chenopodium quinoa , Farinha , Proteínas de Soja/química , Triticum/química , Glutens/química
7.
Am J Orthod Dentofacial Orthop ; 164(1): 116-122, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36858877

RESUMO

INTRODUCTION: Mini-implants are now widely used in orthodontic treatment. Soft-tissue inflammation around the mini-implant is an important factor affecting its stability. This study aimed to investigate the periodontal status and the bacterial composition around mini-implants. METHODS: A total of 79 mini-implants in 40 patients (aged 18-45 years) were evaluated in this study. The mini-implant probing depth (mPD), mini-implant gingival sulcus bleeding index (mBI), mini-implant plaque index (mPLI), and the composition of the supragingival and subgingival plaque around the mini-implants were recorded. After Congo red staining, the bacteria were classified and counted under a light microscope. RESULTS: The mPLI and mBI around mini-implants in the infrazygomatic crest were higher than those in the buccal shelf and interradicular area. The mPD was higher on the coronal site of the mini-implant than on the mesial, distal, and apical sites in the infrazygomatic crest. The mPLI around the mini-implant was positively correlated with the mBI, and the mBI was positively correlated with the mPD. The supragingival and subgingival bacterial composition around the mini-implants was similar to that of natural teeth. Compared with supragingival bacterial composition, the subgingival bacteria of mini-implants had a significantly lower proportion of cocci and a higher proportion of bacilli and spirochetes. CONCLUSIONS: The bacteria composition of the plaque and the location are important factors in the inflammation around mini-implants. Similar to natural teeth, mini-implants require health maintenance to prevent inflammation of the surrounding soft tissue and maintain stability.


Assuntos
Implantes Dentários , Placa Dentária , Dente , Humanos , Bactérias , Inflamação
8.
Am J Orthod Dentofacial Orthop ; 164(5): 665-673, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37318427

RESUMO

INTRODUCTION: Mini-implant insertion in the maxillary posterior region can be influenced by anatomic limitations, thus increasing the failure rate. We explored the feasibility of a new implantation site: the region between the mesial and distal buccal roots of the maxillary first molar. METHODS: Cone-beam computed tomography data from 177 patients were collected from a database. The maxillary first molars were morphologically classified by analyzing the angle and morphology of the mesial and distal buccal roots. Next, 77 subjects were randomly selected from the 177 patients to measure and analyze the hard-tissue morphology in the maxillary posterior region. RESULTS: We devised the Morphological Classification on the Mesial and Distal Buccal Roots of Maxillary First Molar (MCBRMM), divided into 3 types: MCBRMM-I, II, and III. In all subjects, MCBRMM-I, II, and III accounted for 43%, 25%, and 32%, respectively. At 8 mm from the mesial cementoenamel junction of maxillary first molars, the interradicular distance between the maxillary first molar's mesiodistal buccal roots of MCBRMM-I was 2.6 mm, showing an upward trend from the cementoenamel junction to the apex. The distance from the buccal bone cortex to the palatal root was >9 mm. The buccal cortical thickness was >1 mm. CONCLUSIONS: This study provided a potential site for mini-implant insertion in the maxillary posterior region: the alveolar bone of maxillary first molars in MCBRMM-I.


Assuntos
Implantes Dentários , Humanos , Estudos de Viabilidade , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Maxila/diagnóstico por imagem , Maxila/cirurgia , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Dente Molar/anatomia & histologia
9.
Cardiovasc Diabetol ; 21(1): 114, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739511

RESUMO

OBJECTIVE: Admission hyperglycemia is associated with poor prognosis in patients with acute myocardial infarction (AMI), but the effects of baseline diabetes status on this association remain elusive. We aim to investigate the impact of admission hyperglycemia on short and long-term outcomes in diabetic and non-diabetic AMI patients. METHODS: In this retrospective cohort study, 3330 patients with regard to first-time AMI between July 2012 and July 2020 were identified. Participants were divided into two groups according to diabetes status (1060 diabetic patients and 2270 non-diabetic patients). Thereafter, they were divided into four groups according to diabetes status-specific cutoff values of fasting blood glucose (FBG) identified by restricted cubic spline. Short-term outcomes included in-hospital death and cardiac complications. Long-term outcomes were all-cause mortality and major adverse cardiovascular events (MACE). Inverse probability of treatment weighting (IPTW) was conducted to adjust for baseline differences among the groups, followed by a weighted Cox proportional hazards regression analysis to calculate hazard ratios and 95% confidence intervals for all-cause mortality associated with each FBG category. Subgroup analysis and sensitivity analysis were performed to test the robustness of our findings. RESULTS: During a median follow-up of 3.2 years, 837 patients died. There was a significant interaction between diabetes status and FBG levels for all-cause mortality during long-term follow-up (p-interaction < 0.001). Moreover, restricted cubic spline curves for the association between FBG and all-cause mortality followed a J shape in patients with diabetes and a non-linear in patients without diabetes. Kaplan-Meier analysis demonstrated greater survival in non-hyperglycemia patients compared to hyperglycemia patients for both diabetic and non-diabetic patients groups. Survival of hyperglycemia patients without diabetes greater than in hyperglycemia patients with diabetes. In the weighted Multivariable cox analysis, admission hyperglycemia predicted higher short and long-term mortality. Subgroup analysis and sensitivity analysis showed the robustness of the results. CONCLUSIONS: The inflection points of FBG level for poor prognosis were 5.60 mmol/L for patients without diabetes and 10.60 mmol/L for patients with diabetes. Admission hyperglycemia was identified as an independent predictor of worse short and long-term outcomes in AMI patients, with or without diabetes. These findings should be explored further.


Assuntos
Diabetes Mellitus , Hiperglicemia , Infarto do Miocárdio , Glicemia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Mortalidade Hospitalar , Humanos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/terapia , Prognóstico , Estudos Retrospectivos
10.
BMC Pregnancy Childbirth ; 22(1): 687, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36068506

RESUMO

BACKGROUND: A significant proportion of women with preeclampsia (PE) exhibit persistent postpartum hypertension (PHTN) at 3 months postpartum associated with cardiovascular morbidity. This study aimed to screen patients with PE to identify the high-risk population with persistent PHTN. METHODS: This retrospective cohort study enrolled 1,000 PE patients with complete parturient and postpartum blood pressure (BP) profiles at 3 months postpartum. The enrolled patients exhibited new-onset hypertension after 20 weeks of pregnancy, while those with PE superimposed upon chronic hypertension were excluded. Latent class cluster analysis (LCCA), a method of unsupervised learning in machine learning, was performed to ascertain maternal exposure clusters from eight variables and 35 subordinate risk factors. Logistic regression was applied to calculate odds ratios (OR) indicating the association between clusters and PHTN. RESULTS: The 1,000 participants were classified into three exposure clusters (subpopulations with similar characteristics) according to persistent PHTN development: high-risk cluster (31.2%), medium-risk cluster (36.8%), and low-risk cluster (32.0%). Among the 1,000 PE patients, a total of 134 (13.4%) were diagnosed with persistent PHTN, while the percentages of persistent PHTN were24.68%, 10.05%, and 6.25% in the high-, medium-, and low-risk clusters, respectively. Persistent PHTN in the high-risk cluster was nearly five times higher (OR, 4.915; 95% confidence interval (CI), 2.92-8.27) and three times (OR, 2.931; 95% CI, 1.91-4.49) than in the low- and medium-risk clusters, respectively. Persistent PHTN did not differ between the medium- and low-risk clusters. Subjects in the high-risk cluster were older and showed higher BP, poorer prenatal organ function, more adverse pregnancy events, and greater medication requirement than the other two groups. CONCLUSION: Patients with PE can be classified into high-, medium-, and low-risk clusters according to persistent PHTN severity; each cluster has cognizable clinical features. This study's findings stress the importance of controlling persistent PHTN to prevent future cardiovascular disease.


Assuntos
Hipertensão , Pré-Eclâmpsia , Análise por Conglomerados , Feminino , Humanos , Hipertensão/epidemiologia , Período Pós-Parto , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Gravidez , Estudos Retrospectivos , Fatores de Risco
11.
J Mol Recognit ; 33(1): e2814, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31637788

RESUMO

Maillard reaction occurs between the carbonyl group of reducing sugars and the free amino groups of protein, which eventually results in the formation and accumulation of advanced glycation end products (AGEs) irreversibly. Excessive production of AGEs is associated with many diseases, such as Alzheimer disease, neuropathy, retinopathy, and nephropathy. In this study, the effects of eriodictyol and naringenin on the inhibition of AGEs were studied with bovine serum albumin (BSA)-methylglyoxal (MGO) model by spectroscopic techniques and molecular docking methods. The fluorescence spectroscopy results suggested that eriodictyol and naringenin could inhibit the formation of AGEs. Circular dichroism (CD) studies indicated that eriodictyol and naringenin could stabilize the structure of BSA and inhibit the formation of AGEs. The molecular docking results demonstrated that eriodictyol formed two hydrogen bonds with Lys 350 and Leu 480 and the main forces were hydrogen bonding and hydrophobic interactions. However, naringenin interacted with Arg 484 of BSA, and the main force was hydrophobic interaction. It can be concluded that eriodictyol and naringenin can inhibit the formation of AGEs and eriodictyol has stronger inhibitory activity of AGEs than that of naringenin, which is probably due to the additional hydroxyl group in the position C-3' of B ring of eriodictyol.


Assuntos
Flavanonas/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Dicroísmo Circular , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência/métodos
12.
Phys Rev Lett ; 124(10): 100605, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216397

RESUMO

A powerful perspective in understanding nonequilibrium quantum dynamics is through the time evolution of its entanglement content. Yet apart from a few guiding principles for the entanglement entropy, to date, much less is known about the refined characteristics of entanglement propagation. Here, we unveil signatures of the entanglement evolving and information propagating out of equilibrium, from the view of the entanglement Hamiltonian. We investigate quantum quench dynamics of prototypical Bose-Hubbard model using state-of-the-art numerical technique combined with conformal field theory. Before reaching equilibrium, it is found that a current operator emerges in the entanglement Hamiltonian, implying that entanglement spreading is carried by particle flow. In the long-time limit the subsystem enters a steady phase, evidenced by the dynamic convergence of the entanglement Hamiltonian to the expectation of a thermal ensemble. Importantly, the entanglement temperature in steady state is spatially independent, which provides an intuitive trait of equilibrium. These findings not only provide crucial information on how equilibrium statistical mechanics emerges in many-body dynamics, but also add a tool to exploring quantum dynamics from the perspective of the entanglement Hamiltonian.

13.
Nanotechnology ; 31(18): 185502, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31945760

RESUMO

The flexible piezoresistive sensor is the key component used to obtain human biological information via wearable electronic systems, and forms the basis of this technology. In order to improve the sensitivity, stability, and simplicity of the flexible piezoresistive sensor, this study innovatively prepared multi-walled carbon nanotube/silver nanowire/polyurethane (MWNT/AgNW/PU) films whose surface had a one-dimensional cube microstructure by using a mixed solution template method, and integrated the resulting microstructured hybrid nanocomposite films (MNFs) with a single-sided interdigital copper electrode. Meanwhile, mechanical finite-element models of MNF were constructed to study the influence of the structure parameters on the response sensitivity. The piezoresistive experiment results show that, within a pressure range of 0-2 kPa, the sensitivity of the sensor is as high as 42.6 kPa-1. Moreover, with the hybridization of MWNTs and AgNW, the mechanical stability, linearity, and hysteresis of the sensor have been significantly improved. The hysteresis error and nonlinear error of sensors with 5 wt% MWNTs and 5 wt% AgNWs can be as low as ±4.15% and ±12.5%, respectively, which is 93.24% and 78.93% lower compared with MWNTs/PU. The simulation experiments show that the contact area of the MNF and the single-sided electrode has a negative correlation with the piezoresistive sensitivity of the sensors. Furthermore, the prepared flexible piezoresistive sensor is used for human body physiological signal monitoring. It provides the possibility of expanding and optimizing the application of flexible sensors in electronic skin, wearable health monitor devices, smart textiles, clothing, and so on.

14.
Ultrastruct Pathol ; 44(1): 42-51, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31902272

RESUMO

A high-fat diet is often associated with cardiovascular diseases. Research has suggested that consumption of a high-fat diet for 10 weeks is associated with cardiac dysfunction, including arrhythmias, through alterations in cardiac remodeling and myocardial intracellular calcium (Ca2+) handling. In this study, rats were randomly divided into two groups: the standard diet (N = 5) and high-fat diet (N = 5) groups. To evaluate the effects of a high-fat diet on cardiac remodeling, we investigated the myocardium obtained from male Wistar rats fed a high-fat diet or standard diet for ten weeks via scanning electron microscopy, polarization microscopy, and RT-PCR. We found that compared with the standard diet cohort, the high-fat diet cohort exhibited increased levels of SERCA2a and SERCA2b mRNA and a decreased level of PLB mRNA (P < .05). These findings showed that a high-fat diet may lead to cardiac upregulation of Ca2+ transport-related genes in the sarcoplasmic reticulum. Additionally, we observed endocardial injury accompanied by focal dense layered collagen, increased spacing between endocardial cells that was often filled with collagen debris, and increased amounts of collagen fibers among enlarged cardiomyocytes in the high-fat diet cohort. The abnormal intracellular calcium (Ca2+) handling and cardiac remodeling may be contributing factors in arrhythmias and sudden cardiac death in high-fat diet-fed rats.


Assuntos
Remodelamento Atrial/fisiologia , Cálcio/metabolismo , Dieta Hiperlipídica/efeitos adversos , Miocárdio/patologia , Miocárdio/ultraestrutura , Animais , Masculino , Miocárdio/metabolismo , Ratos , Ratos Wistar , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
15.
Chem Biodivers ; 17(2): e1900587, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31872502

RESUMO

Anthocyanins (AC) from Coreopsis tinctoria possesses strong antioxidant properties, while the effects of AC on cells damage induced by reactive oxygen species (ROS) in diabetes mellitus diseases progression have not been reported. The present study was carried out to evaluate the protective property of AC against cellular oxidative stress with an experimental model, H2 O2 -exposed MIN6 cells. AC could reverse the decrease of cell viability induced by H2 O2 and efficiently suppressed cellular ROS production and cell apoptosis. In addition, Real-time PCR and Western blot analyses indicated that AC could protect MIN6 cells against oxidative injury through increasing the translocation of Nrf2 into nuclear, decreasing the phosphorylation level of p38 and up-regulating the protein expression of antioxidant enzyme (SOD1, SOD2 and CAT). Thus, this study provides evidence to support the beneficial effect of AC in inhibiting MIN6 cells from H2 O2 -induced oxidative injury.


Assuntos
Antocianinas/química , Coreopsis/química , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Antocianinas/farmacologia , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Coreopsis/metabolismo , Peróxido de Hidrogênio/toxicidade , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/química , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Regulação para Cima/efeitos dos fármacos
16.
Chem Biodivers ; 17(11): e2000382, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32914574

RESUMO

Oxidative damage in cells induced by reactive oxygen species (ROS) is a main factor in diabetes mellitus diseases progression. The composition of anthocyanins from Padus racemosa (APR) and the protective effects of APR on H2 O2 -induced rat insulinoma (INS-1) cells damage and streptozocin (STZ)-induced diabetes mice were investigated in this study. The main components of APR were cyanidin-cyanidin glucosyl-rutinoside, cyanidin-cyanidin xylosyl-rutinoside, cyanidin-xylosyl-glucoside and cyanidin-rutinoside, which were determined by liquid chromatography-mass spectrometry (LC/MS). APR could scavenge the 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical and superoxide radical in vitro. ROS level was decreased and the cell viability was increased in INS-1 cells after treated with APR. Cell apoptosis induced by H2 O2 in INS-1 cells was decreased after incubation with APR. APR could decrease the phosphorylation of p38 and the nuclear translocation of p65, which indicated that APR could inhibit the activation of p38 Mitogen-activated protein kinase (MAPK) and Nuclear factor kappa B (NF-κB) cell signaling pathways. Meanwhile, APR could effectively reduce the blood glucose and blood lipid in STZ-induced diabetic mice. These results suggested that APR might be a potential agent for diabetes mellitus diseases treatment.


Assuntos
Antocianinas/química , Apoptose/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Substâncias Protetoras/química , Prunus/química , Animais , Antocianinas/isolamento & purificação , Antocianinas/farmacologia , Antocianinas/uso terapêutico , Antioxidantes/química , Glicemia/análise , Linhagem Celular Tumoral , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Frutas/química , Frutas/metabolismo , Camundongos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Extratos Vegetais/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Prunus/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
J Mol Recognit ; 32(7): e2779, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30701606

RESUMO

Eriocitrin is a flavanone glycoside, which exists in lemon or lime citrus fruits. It possesses antioxidant, anticancer, and anti-allergy activities. In order to investigate the pharmacokinetics and pharmacological mechanisms of eriocitrin in vivo, the interaction between eriocitrin and bovine serum albumin (BSA) was studied under the simulated physiological conditions by multispectroscopic and molecular docking methods. The results well indicated that eriocitrin and BSA formed a new eriocitrin-BSA complex because of intermolecular interactions, which was demonstrated by the results of ultraviolet-visible (UV-vis) absorption spectra. The intrinsic fluorescence of BSA was quenched by eriocitrin, and static quenching was the quenching mechanism. The number of binding sites (n) and binding constant (Kb ) at 310 K were 1.22 and 2.84 × 106  L mol-1 , respectively. The values of thermodynamic parameters revealed that the binding process was spontaneous, and the main forces were the hydrophobic interaction. The binding distance between eriocitrin and BSA was 3.43 nm. In addition, eriocitrin changed the conformation of BSA, which was proved by synchronous fluorescence and circular dichroism (CD) spectra. The results of site marker competitive experiments suggested that eriocitrin was more likely to be inserted into the subdomain IIA (site I), which was further certified by molecular docking studies.


Assuntos
Flavanonas/farmacologia , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Animais , Sítios de Ligação , Bovinos , Dicroísmo Circular , Flavanonas/química , Conformação Molecular , Simulação de Acoplamento Molecular , Ligação Proteica , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
18.
Phys Rev Lett ; 123(20): 207203, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31809074

RESUMO

We study the spin liquid candidate of the spin-1/2 J_{1}-J_{2} Heisenberg antiferromagnet on the triangular lattice by means of density matrix renormalization group (DMRG) simulations. By applying an external Aharonov-Bohm flux insertion in an infinitely long cylinder, we find unambiguous evidence for gapless U(1) Dirac spin liquid behavior. The flux insertion overcomes the finite size restriction for energy gaps and clearly shows gapless behavior at the expected wave vectors. Using the DMRG transfer matrix, the low-lying excitation spectrum can be extracted, which shows characteristic Dirac cone structures of both spinon-bilinear and monopole excitations. Finally, we confirm that the entanglement entropy follows the predicted universal response under the flux insertion.

19.
Cell Commun Signal ; 17(1): 99, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429768

RESUMO

BACKGROUND: Excessive estrogen exposure is an important pathogenic factor in uterine endometrial cancer (UEC). Recent studies have reported the metabolic properties can influence the progression of UEC. However, the underlying mechanisms have not been fully elucidated. METHODS: Glutaminase (GLS), MYC and autophagy levels were detected. The biological functions of estrogen-MYC-GLS in UEC cells (UECC) were investigated both in vivo and in vitro. RESULTS: Our study showed that estrogen remarkably increased GLS level through up-regulating c-Myc, and enhanced glutamine (Gln) metabolism in estrogen-sensitive UEC cell (UECC), whereas fulvestrant (an ER inhibitor antagonist) could reverse these effects. Estrogen remarkably promoted cell viability and inhibited autophagy of estrogen sensitive UECC. However, CB-839, a potent selective oral bioavailable inhibitor of both splice variants of GLS, negatively regulated Gln metabolism, and inhibited the effects of Gln and estrogen on UECC's growth and autophagy in vitro and / or in vivo. CONCLUSIONS: CB-839 triggers autophagy and restricts growth of UEC by suppressing ER/Gln metabolism, which provides new insights into the potential value of CB-839 in clinical treatment of estrogen-related UEC.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias do Endométrio/tratamento farmacológico , Estrogênios/farmacologia , Glutamina/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Glutaminase/metabolismo , Humanos , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
20.
Chem Biodivers ; 16(10): e1900174, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31419039

RESUMO

The advanced glycation end products (AGEs) are the compounds produced by non-enzymatic glycation reaction of proteins and sugars, which can induce the generation of free radicals and the expression of inflammatory factors, thereby playing an important role in vascular dysfunction in diabetes. To investigate the effects of caffeic acid (CA) on glycation formed by glucose and protein, various spectroscopic techniques and molecular docking methods were carried out. Furthermore, the protective effects of CA on human umbilical vein endothelial cells (HUVECs) damaged by AGEs were detected. The results indicated that CA inhibited AGEs formation in vitro, decreased the expression of IL-1ß, IL-18, ICAM-1, VCAM-1, NLRP3, Caspase-1 and CRP (C-reactive protein) and reduced the ROS in HUVECs exposed to AGEs. Our findings suggested that the supplementation with dietary CA could prevent and delay the AGEs-induced vascular dysfunction in diabetes.


Assuntos
Ácidos Cafeicos/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inflamação/tratamento farmacológico , Ácidos Cafeicos/química , Células Cultivadas , Citocinas/antagonistas & inibidores , Citocinas/genética , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Produtos Finais de Glicação Avançada/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/metabolismo , Simulação de Acoplamento Molecular , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
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