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1.
Nature ; 627(8005): 754-758, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38093004

RESUMO

Shock-breakout emission is light that arises when a shockwave, generated by the core-collapse explosion of a massive star, passes through its outer envelope. Hitherto, the earliest detection of such a signal was at several hours after the explosion1, although a few others had been reported2-7. The temporal evolution of early light curves should provide insights into the shock propagation, including explosion asymmetry and environment in the vicinity, but this has been hampered by the lack of multiwavelength observations. Here we report the instant multiband observations of a type II supernova (SN 2023ixf) in the galaxy M101 (at a distance of 6.85 ± 0.15 Mpc; ref. 8), beginning at about 1.4 h after the explosion. The exploding star was a red supergiant with a radius of about 440 solar radii. The light curves evolved rapidly, on timescales of 1-2 h, and appeared unusually fainter and redder than predicted by the models9-11 within the first few hours, which we attribute to an optically thick dust shell before it was disrupted by the shockwave. We infer that the breakout and perhaps the distribution of the surrounding dust were not spherically symmetric.

2.
Langmuir ; 40(22): 11670-11683, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38773956

RESUMO

In this study, vanadium carbide (VC) was used as the raw material to synthesize PDA-functionalized VC (P-VC). VC and P-VC were added as nanoreinforced materials to the Ni-W-B coating. The effects of the two nanomaterials on the morphology, wear resistance, and corrosion resistance of the Ni-W-B coatings were investigated and compared. The experimental results show that the surface of the Ni-W-B/P-VC coating is denser and more uniform than that of the Ni-W-B and Ni-W-B/VC coatings, and there are no obvious defects on the surface. According to the hardness test, the Ni-W-B/P-VC coating reaches the highest microhardness of 887.1 HV. According to the friction and wear tests, the Ni-W-B/P-VC coating has the shallowest scratches, the lowest average friction coefficient (COF = 0.274), and the lowest wear rate (9.578 × 10-8 mm2/N). The corrosion resistance is the best, the corrosion rate is 0.0456 mm/y, and the impedance value Rt reaches 14,501 Ω·cm2.

3.
New Phytol ; 238(3): 1073-1084, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36727295

RESUMO

DNA double-strand breaks (DSBs) are the most toxic form of DNA damage in cells. Homologous recombination (HR) is an error-free repair mechanism for DSBs as well as a basis for gene targeting using genome-editing techniques. Despite the importance of HR, the HR mechanism in plants is poorly understood. Through genetic screens for DNA damage response mutants (DDRMs), we find that the Arabidopsis ddrm2 mutant is hypersensitive to DSB-inducing reagents. DDRM2 encodes a protein with four BRCA1 C-terminal (BRCT) domains and is highly conserved in plants including bryophytes, the earliest land plant lineage. The plant-specific transcription factor SOG1 binds to the promoter of DDRM2 and activates its expression. In consistence, the expression of DDRM2 is induced by DSBs in a SOG1-dependent manner. In support, genetic analysis suggests that DDRM2 functions downstream of SOG1. Similar to the sog1 mutant, the ddrm2 mutant shows dramatically reduced HR efficiency. Mechanistically, DDRM2 interacts with the core HR protein RAD51 and is required for the recruitment of RAD51 to DSB sites. Our study reveals that SOG1-DDRM2-RAD51 is a novel module for HR, providing a potential target for improving the efficiency of gene targeting.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Dano ao DNA , Recombinação Homóloga , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Quebras de DNA de Cadeia Dupla , Dano ao DNA/genética , Reparo do DNA , Recombinação Homóloga/genética , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Fatores de Transcrição/metabolismo
4.
Appl Opt ; 62(6): 1537-1546, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36821315

RESUMO

Due to numerous edible oil safety problems in China, an automatic oil quality detection technique is urgently needed. In this study, rough set theory and Fourier transform spectrum are combined for proposing a digital identification method for edible oil. First, the Fourier transform spectra of three different types of edible oil samples, including colza oil, waste oil, and peanut oil, are measured. After the input spectra are differentially and smoothly processed, the characteristic wavelength bands are selected with neighborhood rough set attribution reduction (NRSAR). Moreover, the classification models are established based on random forest (RF) and extreme learning machine (ELM) algorithms. Finally, confusion matrix, classification accuracy, sensitivity, specificity, and the distribution of judgment are calculated for evaluating the classification performances of different models and determining the optimal oil identification model. The results show that by using the third-order difference pre-processing method, 193 wavelength bands in the visible range can be reduced to 10 characteristic wavelengths, with a compression ratio of over 88.61%. Using the established NRS-RF and NRS-ELM models, the total identification accuracies are 91.67% and 93.33%, respectively. In particular, the identification accuracy of peanut oil using the NRS-ELM model reaches up to 100%, whereas the identification accuracies obtained using the principal component analysis (PCA)-based models that are commonly used in information processing (PCA-RF and PCA-ELM) are 81.67% and 90.00%, respectively. As compared with feature extraction methods, the proposed NRSAR shows directive advantages in terms of precision, sensitivity, specificity, and the distribution of judgment. In addition, the execution time is also reduced by approximately 1/3. Conclusively, the NRSAR method and NRS-ELM the model in the spectral identification of edible oil show favorable performance. They are expected to bring forth insightful oil identification techniques.

5.
Phytother Res ; 37(5): 1951-1967, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36631974

RESUMO

Increased glycolytic in fibroblast-like synoviocytes (FLS) of rheumatoid arthritis (RA) not only contributes to early-stage disease pathogenesis but leads to sustained proliferation of FLS. Given the importance of PKM2 in glycolysis and apoptosis, PKM2 is considered a potential therapeutic and drug discovery target in RA. Total saponins of anemarrhena (TSA), a class of steroid saponins, originated from Anemarrhena asphodeloides Bge. In this study, we verified that 200 mg/kg TSA could significantly alleviate inflammation and the pathological characteristics of RA and inhibit synovial hyperplasia in AA rats. We confirmed that sarsasapogenin (SA) was the principal active ingredient absorbed into the blood of TSA by the UPLC/Q Exactive MS test. Then we used TNF-α-induced MH7A to get the conclusion that 20 µM SA could effectively inhibit the glycolysis by inhibiting the activity of PKM2 tetramer and glucose uptake. Moreover, 20 µM SA could suppress proliferation, migration, invasion, and cytokine release of FLS, interfere with the growth cycle of FLS, and induce FLS apoptosis by depressing the phosphorylation of PKM2. At last, In-1, a potent inhibitor of the PKM2 was used to reverse verify the above results. Taken together, the key mechanisms of SA on RA treatment through downregulating the activity of PKM2 tetramer and phosphorylation of PKM2 inhibited pathological glycolysis and induced apoptosis to exert inhibition on the proliferation and invasion of RA FLS.


Assuntos
Anemarrhena , Artrite Reumatoide , Sinoviócitos , Animais , Ratos , Anemarrhena/química , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Proliferação de Células , Células Cultivadas , Fibroblastos , Glicólise , Membrana Sinovial , Saponinas/farmacologia
6.
Phytother Res ; 37(6): 2454-2471, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36772986

RESUMO

Mitochondrial inflammation triggered by abnormal mitochondrial division and regulated by the Drp1/HK1/NLRP3 pathway is correlated with the progression of aging-associated cognitive impairment (AACI). Alpinetin is a novel flavonoid derived from Zingiberaceae that has many bioactivities such as antiinflammation and anti-oxidation. However, whether alpinetin alleviates AACI by suppressing Drp1/HK1/NLRP3 pathway-inhibited mitochondrial inflammation is still unknown. In the present study, D-galactose (D-gal)-induced aging mice and BV-2 cells were used, and the effects of alpinetin on learning and memory function, neuroprotection and activation of the Drp1/HK1/NLRP3 pathway were investigated. Our data indicated that alpinetin significantly alleviated cognitive dysfunction and neuronal damage in the CA1 and CA3 regions of D-gal-treated mice. Moreover, D-gal-induced microglial activation was markedly reduced by alpinetin by inhibiting the Drp1/HK1/NLRP3 pathway-suppressed mitochondrial inflammation, down-regulating the levels of p-Drp1 (s616), VDAC, NLRP3, ASC, Cleaved-caspase 1, IL-18, and IL-1ß, and up-regulating the expression of HK1. Furthermore, after Drp1 inhibition by Mdivi-1 in vitro, the inhibitory effect of alpinetin on Drp1/HK1/NLRP3 pathway was more evident. In summary, the current results implied that alpinetin attenuated aging-related cognitive deficits by inhibiting the Drp1/HK1/NLRP3 pathway and suppressing mitochondrial inflammation, suggesting that the inhibition of the Drp1/HK1/NLRP3 pathway is one of the mechanisms by which alpinetin attenuates AACI.


Assuntos
Disfunção Cognitiva , Proteína 3 que Contém Domínio de Pirina da Família NLR , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamação/tratamento farmacológico , Envelhecimento , Galactose/efeitos adversos , Disfunção Cognitiva/tratamento farmacológico
7.
Drug Chem Toxicol ; 45(1): 231-238, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746246

RESUMO

Recently, increasing numbers of studies have shown that the consumption of large amounts of alcohol is a major risk factor for dementias, which has led to widespread concern about the harmful effects of alcohol consumption on health. However, the pathological changes in the brain caused by this habit are not clear. This study aimed to investigate the possible causes by determining the permeability of the blood-brain barrier (BBB), pathomorphological changes, the mRNA, and protein expressions of adhesion proteins and the concentrations of ß-amyloid (Aß) and some related functional proteins in the brains of C57BL/6 and APPswe/PS1dE9 mice before and after intragastric administration of alcohol for 2 months. The results showed that long-term consumption of alcohol aggravated cognitive decline, increased the permeability of the BBB, led to pathomorphological changes and downregulated some related structural proteins (zonula occludens-1, VE-cadherin, and occludin) and functional proteins (major facilitator superfamily domain-containing protein-2a (Mfsd2a), low-density lipoprotein receptor-related protein-1 (LRP1), receptor for advanced glycation end products (RAGE), and aquaporin-4 (AQP4)) in the BBB but did not increase the concentration of Aß1-42. These novel findings suggested that long-term consumption of alcohol induces neural lesions, which is related to the destruction of the integrity of the BBB.


Assuntos
Peptídeos beta-Amiloides , Barreira Hematoencefálica , Peptídeos beta-Amiloides/metabolismo , Animais , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
8.
J Headache Pain ; 23(1): 1, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979902

RESUMO

BACKGROUND: Chronic migraine places a disabling burden on patients, which is extensively modeled by the nitroglycerin (NTG)-treated animal model. Although the NF-κB pathway is involved in an increase in CGRP levels and activation of the trigeminal system in the NTG model, the relationship between NTG and neuroinflammation remains unclear. This study aimed to optimize a chronic NTG rat model with hyperalgesia and the ethological capacity for estimating migraine therapies and to further explore the underlying mechanism of NTG-induced migraine. METHODS: Rats were administered different doses of NTG s.c. daily or every 2 d; 30 min and 2 h later, the mechanical threshold was tested. After 9 d, the rats were injected with EB or Cy5.5 for the permeability assay. The other animals were sacrificed, and then, brainstem and caudal trigeminal ganglion were removed to test CGRP, c-Fos and NOS activity; Cytokines levels in the tissue and serum were measured by ELISA; and NF-κB pathway and blood-brain barrier (BBB)-related indicators were analyzed using western blotting. Immunohistochemistry was performed to observe microglial polarization and IL-17A+ T cell migration in the medulla oblongata. RESULTS: NTG (10 mg/kg, s.c., every 2 d for a total of 5 injections) was the optimal condition, resulting in progressive hyperalgesia and migraine behavior. TNC neuroinflammation with increases in cytokines, CGRP and c-Fos and activation of the NF-κB pathway was observed, and these changes were alleviated by ibuprofen. Furthermore, NTG administration increased BBB permeability by altering the levels functional proteins (RAGE, LRP1, AQP4 and MFSD2A) and structural proteins (ZO-1, Occludin and VE-cadherin-2) to increase peripheral IL-17A permeation into the medulla oblongata, activating microglia and neuroinflammation, and eventually causing hyperalgesia and migraine attack. CONCLUSIONS: This study confirmed that NTG (10 mg/kg, s.c., every 2 d for a total of 5 injections) was the optimal condition to provoke migraine, resulting in mechanical hyperalgesia and observable migraine-like behavior. Furthermore, IL-17A crossed the blood-brain barrier into the medulla oblongata, triggering TNC activation through microglia-mediated neuroinflammation. This process was a novel mechanism in NTG-induced chronic migraine, suggesting that IL-17A might be a novel target in the treatment of migraine.


Assuntos
Transtornos de Enxaqueca , Nitroglicerina , Animais , Barreira Hematoencefálica , Modelos Animais de Doenças , Humanos , Interleucina-17 , Transtornos de Enxaqueca/induzido quimicamente , Doenças Neuroinflamatórias , Nitroglicerina/toxicidade , Ratos
9.
Anal Chem ; 93(48): 16264-16272, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34797071

RESUMO

Specific and sensitive detection and imaging of cancer-related miRNA in living cells are desirable for cancer diagnosis and treatment. Because of the spatiotemporal variability of miRNA expression level during different cell cycles, signal amplification strategies that can be activated by external stimuli are required to image miRNAs on demand at desired times and selected locations. Herein, we develop a signal amplification strategy termed as the photoactivated DNA walker based on DNA nanoflares, which enables photocontrollable signal amplification imaging of cancer-related miRNA in single living cells. The developed method is achieved via combining photoactivated nucleic acid displacement reaction with the traditional exonuclease III (EXO III)-assisted DNA walker based on DNA nanoflares. This method is capable of on-demand activation of the DNA walker for dictated signal amplification imaging of cancer-related miRNA in single living cells. The developed method was demonstrated as a proof of concept to achieve photoactivated signal amplification imaging of miRNA-21 in single living HeLa cells via selective two-photon irradiation (λ = 740 nm) of single living HeLa cells by using confocal microscopy equipped with a femtosecond laser.


Assuntos
Técnicas Biossensoriais , MicroRNAs , DNA/genética , Células HeLa , Humanos , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico
10.
Brain Behav Immun ; 93: 264-276, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33548498

RESUMO

Meningeal immunity refers to immune surveillance and immune defense in the meningeal immune compartment, which depends on the unique position, structural composition of the meninges and functional characteristics of the meningeal immune cells. Recent research advances in meningeal immunity have demonstrated many new ways in which a sophisticated immune landscape affects central nervous system (CNS) function under physiological or pathological conditions. The proper function of the meningeal compartment might protect the CNS from pathogens or contribute to neurological disorders. Since the concept of meningeal immunity, especially the meningeal lymphatic system and the glymphatic system, is relatively new, we will provide a general review of the meninges' basic structural elements, organization, regulation, and functions with regards to meningeal immunity. At the same time, we will emphasize recent evidence for the role of meningeal immunity in neurodegenerative diseases. More importantly, we will speculate about the feasibility of the meningeal immune region as a drug target to provide some insights for future research of meningeal immunity.


Assuntos
Sistema Glinfático , Doenças Neurodegenerativas , Sistema Nervoso Central , Humanos , Sistema Linfático , Meninges
11.
Acta Pharmacol Sin ; 42(1): 45-54, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32451415

RESUMO

Lifestyle factors may affect mental health and play a critical role in the development of neurodegenerative diseases including Alzheimer's disease (AD). However, whether the temperatures of daily beverages have any impact on cognitive function and AD development has never been studied. In this study, we investigated the effects of daily drinking water temperatures on cognitive function and AD development and progression in mice and the underlying mechanisms. Cognitive function of mice was assessed using passive avoidance test, open field test, and Morris water maze. Wild-type Kunming mice receiving intragastric water (IW, 10 mL/kg, 2 times/day) at 0 °C for consecutive 15 days displayed significant cognitive defects accompanied by significant decrease in gain of body weight, gastric emptying rate, pepsin activity, and an increase in the energy charge in the cortex when compared with mice receiving the same amount of IW at 25 °C (a temperature mimicking most common drinking habits in human), suggesting the altered neuroenergetics may cause cognitive decline. Similarly, in the transgenic APPwse/PS1De9 familial AD mice and their age- and gender-matched wild-type C57BL/6 mice, receiving IW at 0 °C, but not at 25 °C, for 35 days caused a significant time-dependent decrease in body weight and cognitive function, accompanied by a decreased expression of PI3K, Akt, the glutamate/GABA ratio, as well as neuropathy with significant amyloid lesion in the cortex and hippocampus. All of these changes were significantly aggravated in the APPwse/PS1De9 mice than in the control C57BL/6 mice. These data demonstrate that daily beverage at 0 °C may alter brain insulin-mediated neuroenergetics, glutamate/GABA ratio, cause cognitive decline and neuropathy, and promote AD progression.


Assuntos
Doença de Alzheimer/fisiopatologia , Cognição/fisiologia , Temperatura Baixa , Água Potável/administração & dosagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Progressão da Doença , Água Potável/química , Ácido Glutâmico/metabolismo , Insulina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Teste do Labirinto Aquático de Morris/fisiologia , Neurotransmissores/metabolismo , Teste de Campo Aberto/fisiologia , Transdução de Sinais/fisiologia , Ácido gama-Aminobutírico/metabolismo
12.
J Card Surg ; 36(7): 2381-2388, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33960508

RESUMO

BACKGROUND AND AIM OF THE STUDY: Many studies support that the no-touch (NT) procedure can improve the patency rate of vein grafts. However, it is not clear that the sequential vein graft early expansion in the NT technique during off-pump coronary artery bypass grafting (CABG). This study will explore this issue. METHODS: This was a prospective single-center randomized controlled clinical trial. A total of 100 patients undergoing off-pump CABG with the sequential saphenous graft were randomly assigned to two groups: the NT and conventional (CON) groups. Perioperative and postoperative data were collected during the hospital stay. The mean diameter of sequential grafts was measured using cardiac computed tomography angiography 3 months after the operation. RESULTS: There was a significant difference in the average diameter of sequential grafts between the two groups (NT: [2.98 ± 0.42], CON: [3.26 ± 0.51], p = .005). There was no difference in occlusion of sequential venous grafts between the two groups (NT: 4/48 [8.3%], CON: 5/49 [10.2%], p = 1.000). There were differences in surgery time between the two groups (NT: 220 [188,240], CON: 190 [175,230], p = .009). CONCLUSIONS: The sequential graft early expansion in the NT technique is not as pronounced as that in the conventional technique, which may have a long-term protective effect on the grafts.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Veia Safena , Angiografia Coronária , Ponte de Artéria Coronária , Humanos , Estudos Prospectivos , Veia Safena/diagnóstico por imagem , Resultado do Tratamento , Grau de Desobstrução Vascular
13.
Phytother Res ; 35(3): 1572-1584, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33111362

RESUMO

Ligustilide is a phenolic compound isolated from Asian plants of Umbelliferae family. This study was aimed at exploring the neuroprotective effects of Ligustilide from the perspective of endoplasmic reticulum stress (ERS) and autophagy. The Alzheimer's disease (AD) cell models were constructed by SH-SY5Y cell line, which was exposed to 20 µM Aß25-35 . CCK-8 was used to evaluate the cell viability of Ligustilide on AD cell model. Hoechst staining and LysoTracker Red were used to test the cell apoptosis and Lysosome function, respectively. ERS in living cells were detected by Thioflavin T. The expression of autophagy-related proteins (LC3B-II/I, P62/SQSTM1, Beclin1, and Atg5), ERS marker proteins (PERK, GRP78, and CHOH), and apoptosis proteins (Bax, Bcl-2, and Caspase-12) were analyzed by Western blot analyses. Aß25-35 could induce ERS and autophagy in a time-dependent manner in SH-SY5Y cells. We demonstrated that Ligustilide significantly decreased the rate of apoptosis, and improved the viability of cells. Simultaneously, Ligustilide effectively modulated ERS via inhibiting the over-activation of GRP78/PERK/CHOP signaling pathway. In addition, Ligustilide alleviated the accumulation of autophagy vacuoles, reduced the ratio of LC3B-II/I and the level of P62/SQSTM1. Ligustilide significantly up-regulated lysosomal acidity and the expression of Cathepsin D (CTSD). Ligustilide could rescue lysosomal function to promote autophagy flux and inhibit the over-activation of ERS. This finding may contribute to the development of new therapeutic strategies for AD.


Assuntos
4-Butirolactona/análogos & derivados , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , 4-Butirolactona/farmacologia , 4-Butirolactona/uso terapêutico , Apoptose , Chaperona BiP do Retículo Endoplasmático , Humanos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais , Transfecção
14.
Zhongguo Zhong Yao Za Zhi ; 46(1): 41-45, 2021 Jan.
Artigo em Zh | MEDLINE | ID: mdl-33645049

RESUMO

Drying is one of the most common unit operations in the production of traditional Chinese medicine. The drying process of traditional Chinese medicine materials is accompanied by the dynamic reduction of water content. As a key index to determine the end of the drying process, the moisture content of materials plays an important role in improving drying efficiency and saving energy. Recently, the drying process of traditional Chinese medicine is mostly monitored by offline detection, and there are few reports of online moisture detection applications. In this paper, the principle and current application of online inspection technology for the material drying process in different fields were introduced. The significance of online detection technology in drying of traditional Chinese medicine was also analyzed. Meanwhile, the application prospect of online detection technology in the field of drying of traditional Chinese medicine was predicted. In response to urgent transformation and upgrading of the traditional Chinese medicine manufacturing industry, the application of online moisture detection technology is expected to be a key breakthrough in the intelligent upgrading of traditional Chinese medicine drying technology and equipment.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Dessecação , Controle de Qualidade , Tecnologia Farmacêutica
15.
J Am Chem Soc ; 142(24): 10833-10840, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32433875

RESUMO

Constructing hierarchical superstructures to achieve comparable complexity and functions to proteins with four-level hierarchy is challenging, which relies on the elaboration of novel building blocks with complex structures. We present a series of catenated cages with unique structural complexity and tailorability. The rational design was realized as such: A catenane of two symmetric cages (CSC), CSC-1, with all rigid imine panels was converted to a catenane of two dissymmetric cages (CDC), CDC-1, with two exterior flexible amine panels, and CDC-5 was tailored from CDC-1 by introducing an additional methyl group on each blade to increase lateral hindrance. CDC-1s with the most irregular and flexible configuration formed supramolecular dimers, which self-organized into 3D continuous wavelike plank with a three-level hierarchy, previously undiscovered by conventional building blocks. A drastically different 3D triclinic crystalline phase with a four-level hierarchy and trigonal phase with a three-level hierarchy were constructed of distorted CSC-1s and the most symmetric CDC-5s, respectively. The wavelike plank exhibited the lowest order, and the triclinic phase had a lower order than the trigonal phase which had the highest order. It correlates with the configuration of the primary structures, namely, the most disordered shape of CDC-1, the low-order configuration of CSC-1, and the most ordered geometry of CDC-5. The catenated cages with subtle structural differences therefore provide a promising platform for the search of emerging hierarchical superstructures that might be applied to proton conductivity, ferroelectricity, and catalysis.

16.
BMC Cardiovasc Disord ; 20(1): 266, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493248

RESUMO

BACKGROUND: Preventive intra-aortic balloon pump (IABP) for high-risk patients with stable hemodynamics is controversial, and its definition of high-risk is still unclear. This study aimed to investigate the effect of prophylactic IABP on the early outcome of left main disease (LMD) patients receiving off-pump coronary artery bypass grafting (OPCABG) with stable hemodynamics. METHODS: From January 2013 to April 2020, 257 consecutive patients who underwent OPCABG through sternotomy were enrolled in this study. All LMD patients (greater than 70%) had stable hemodynamics (BP>100 mmHg without vasoconstrictor substance infusion). Early outcomes of 125 patients with prophylactic IABP (IABP group) and 132 patients without IABP (Control group) were compared in this study. RESULTS: IABP did not show favorable effect on the conversion to CPB (RR 0.63, 95%CI 0.05-7.89, P = 0.7211), perioperative MI (RR 0.69, 95%CI 0.22-2.12, P = 0.5163), mortality (RR 0.65, 95%CI 0.04-10.25, P = 0.7608) or the composite end of the conversion, MI and mortality (RR 0.63, 95%CI 0.23-1.74, P = 0.3747). There was greater incidence of prolonged ventilation in IABP after adjustment (RR2.16, 95%CI 1.12-4.18, P = 0.0221). There was no IABP-related mortality or limb ischemia. CONCLUSION: No significant difference in early outcomes was observed in hemodynamically stable patients with LMD between prophylactic IABP group and control group. Prophylactic IABP may be unnecessary in patients with LMD undergoing OPCABG.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana/cirurgia , Hemodinâmica , Balão Intra-Aórtico , Idoso , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Ponte de Artéria Coronária sem Circulação Extracorpórea/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Balão Intra-Aórtico/efeitos adversos , Balão Intra-Aórtico/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Procedimentos Desnecessários
17.
Angew Chem Int Ed Engl ; 59(18): 7113-7121, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32003925

RESUMO

Considerable efforts have been made to increase the topological complexity of mechanically interlocked molecules over the years. Three-dimensional catenated structures composed of two or several (usually symmetrical) cages are one representative example. However, owing to the lack of an efficient universal synthetic strategy, interlocked structures made up of dissymmetric cages are relatively rare. Since the space volume of the inner cavity of an interlocked structure is smaller than that outside it, we developed a novel synthetic approach with the voluminous reductant NaBH(OAc)3 that discriminates this space difference, and therefore selectively reduces the outer surface of a catenated dimer composed of two symmetric cages, thus yielding the corresponding catenane with dissymmetric cages. Insight into the template effect that facilitates the catenation of cages was provided by computational and experimental techniques.

18.
Med Sci Monit ; 25: 3998-4004, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31141498

RESUMO

BACKGROUND The aim of this study was to estimate the long-term efficacy of total aortic arch replacement combined with the frozen elephant trunk (TAR+FET) technique for aortic disease following a prior cardiac surgery procedure. MATERIAL AND METHODS We performed TAR+FET for 118 patients for major vessel disease following a prior cardiac procedure with median sternotomy incision. All patients were divided into 5 groups: in group A, the prior major procedure was aortic valve replacement (AVR); in group B, the prior major procedure was isolated ascending aorta replacement; in group C, the prior major procedure was aortic root replacement; in group D, the prior major procedure was aortic arch replacement or intervention; and in group E, the prior major procedure was 'other' cardiac operative procedure. The long-term follow-up visit results were estimated using the Kaplan-Meier method. RESULTS The 30-day mortality rate after the operation was 13.6% (16/118) - 2 died in group A, 1 in group B, 8 in group C, 4 in group D, and 1 in group E. Follow-up visits were completed in 99% of patients. The mean follow-up time was 47.6±36.3 months and 12 patients had died by follow-up, so the total long-term survival rate was 76.3%. One-year survival rates of the 5 groups were 85% (group A), 93.8% (group B), 82.3% (group C), 50% (group D), and 50% (group E), respectively. Five-year survival rates of the 5 groups were 85%, 93.8%, 80.6%, 50%, and 50%, respectively. CONCLUSIONS The TAR+FET technique is feasible and efficacious for aortic reoperation in patients who previously underwent cardiac surgery since the short-term mortality in patients with recurrent aortic arch disease after cardiac surgery is not high.


Assuntos
Aorta Torácica/cirurgia , Dissecção Aórtica/mortalidade , Idoso , Dissecção Aórtica/cirurgia , Prótese Vascular , Implante de Prótese Vascular/métodos , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/mortalidade , China , Feminino , Seguimentos , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
19.
Med Sci Monit ; 25: 409-417, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30638197

RESUMO

BACKGROUND RAW264.7 cells are induced by lipopolysaccharide (LPS) as a rheumatoid arthritis (RA) model. The present study investigated the effect of cimifugin on the proliferation, migration, chemotaxis, and release of inflammation-related factors and inflammation-related signaling pathways of LPS-induced RAW264.7 cells. MATERIAL AND METHODS MTS assay was used to determine the proliferation of RAW264.7 cells. Transwell assay was employed to examine the migration and chemotaxis of the cells. ELISA was performed to measure the contents of chemotactic factors and inflammatory factors in cell culture supernatants. Western blotting was carried out to detect the expression of factors related with MAPKs and NF-κB signaling pathways. RESULTS Cimifugin (0-100 mg/L) had no cytotoxicity for RAW264.7 cells. LPS stimulation induced morphological differentiation of RAW264.7 cells, but intervention by cimifugin inhibited the activation effect by LPS by about 50%. Cimifugin (100 mg/L) decreased the migration and chemotaxis of RAW264.7 cells to 1/3 of that in control cells by decreasing the release of migration- and chemotaxis-associated factors by at least 30%. Cimifugin (100 mg/L) suppressed the release of inflammatory factors from RAW264.7 cells to less than 60% of that in the LPS group. In addition, cimifugin (100 mg/L) inhibited the activities of MAPKs and NF-κB signaling pathways. CONCLUSIONS The present study demonstrates that cimifugin reduces the migration and chemotaxis of RAW264.7 cells and inhibits the release of inflammatory factors and activation of related signaling pathways induced by LPS. Cimifugin may have potential pharmacological effects against RA.


Assuntos
Cromonas/farmacologia , Inflamação/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Cromonas/toxicidade , Ciclo-Oxigenase 2/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Modelos Biológicos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
20.
J Cell Biochem ; 119(7): 6238-6248, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29663529

RESUMO

Cut-like homeobox 1 (CUX1) is a highly conserved homeoprotein that functions as a transcriptional repressor of genes specifying terminal differentiation. We previously showed that liver-specific microRNA-122 (miR-122) regulates the timing of liver development by silencing CUX1 post-transcriptionally. Since the CUX1 protein is expressed in a subset of embryonic tissues, we hypothesized that it is regulated by specific microRNAs (miRNAs) in each cell type during development. Using a large-scale screening method, we identified ten tissue-specific miRNAs from different cell lineages that directly targeted CUX1. An analysis of the interaction between heart-specific microRNA-208a (miR-208a) and CUX1 in the hearts of developing mouse embryos and in P19CL6 cells undergoing cardiac differentiation indicated that CUX1 is regulated by miR-208a during heart development and cardiomyocyte differentiation. Functional analysis of miR-208a in P19CL6 cells using lentiviral-mediated over-expression showed that it regulates the transition between cellular proliferation and differentiation. These results suggest that these tissue-specific miRNAs might play a common role in timing the progression of terminal differentiation of different cell lineages, possibly by silencing the differentiation repressor CUX1.


Assuntos
Diferenciação Celular , Linhagem da Célula/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/antagonistas & inibidores , MicroRNAs/genética , Miócitos Cardíacos/citologia , Proteínas Nucleares/antagonistas & inibidores , Proteínas Repressoras/antagonistas & inibidores , Animais , Proliferação de Células , Células Cultivadas , Células HeLa , Coração/crescimento & desenvolvimento , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Especificidade de Órgãos , Fatores de Transcrição
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