Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 419
Filtrar
1.
Cell Death Dis ; 12(4): 361, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824298

RESUMO

Solute carrier family 25 member 20 (SLC25A20) is a mitochondrial-membrane-carrier protein involved in the transport of acylcarnitines into mitochondrial matrix for oxidation. A previous-integrated-proteogenomic study had identified SLC25A20 as one of the top-three prognostic biomarkers in HCC. However, the expression and the biological function of SLC25A20 have not yet been investigated in HCC. In the present study, we found that SLC25A20 expression is frequently down-regulated in HCC cells mainly due to the up-regulation of miR-132-3p. Down-regulation of SLC25A20 is associated with a poor prognosis in patients with HCC. SLC25A20 suppressed HCC growth and metastasis, both in vitro and in vivo, by suppression of G1-S cell transition, epithelial-to-mesenchymal transition (EMT), and induction of cell apoptosis. Mechanistically, SLC25A20 down-regulation promoted HCC growth and metastasis through suppression of fatty-acid oxidation. Altogether, SLC25A20 plays a critical tumor-suppressive role in carcinogenesis of HCC; SLC25A20 may serve as a novel prognostic factor and therapeutic target for patients with HCC.

2.
Org Lett ; 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33821663

RESUMO

A direct and site-specific alkylation of (sp3)C-H bond with aliphatic boronic acid was achieved. By simply heating glycinates and amines together with alkylboronic acids under an oxygen atmosphere, a variety of unnatural α-amino acids and peptides could be obtained in good yields.

3.
Adv Mater ; : e2005019, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33834550

RESUMO

Polyoxometalates (POMs) are a series of molecular metal oxide clusters, which span the two domains of solutes and solid metal oxides. The unique characters of POMs in structure, geometry, and adjustable redox properties have attracted widespread attention in functional material synthesis, catalysis, electronic devices, and electrochemical energy storage and conversion. This review is focused on the links between the intrinsic charge carrier behaviors of POMs from a chemistry-oriented view and their recent ground-breaking developments in related areas. First, the advantageous charge transfer behaviors of POMs in molecular-level electronic devices are summarized. Solar-driven, thermal-driven, and electrochemical-driven charge carrier behaviors of POMs in energy generation, conversion and storage systems are also discussed. Finally, present challenges and fundamental insights are discussed as to the advanced design of functional systems based upon POM building blocks for their possible emerging application areas.

4.
Bioengineered ; 12(1): 948-959, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33724167

RESUMO

Neuronal apoptosis was considered as one of the main factors of cerebral ischemia/reperfusion injury. Understanding the molecular regulatory mechanism of neuronal apoptosis under the cerebral ischemia/reperfusion injury may provide the novel therapeutic targets for cerebral ischemia/reperfusion injury. However, the molecular regulatory mechanism of neurons fate determination under the cerebral ischemia/reperfusion injury remains poorly understood. This study was aimed to delve into the related molecular mechanism of miR-484 on the regulation of cerebral ischemia/reperfusion injury-induced neuronal apoptosis in mice. In this study, quantitative real-time polymerase chain reaction assays revealed that the expression level of miR-484 was down-regulated in neurons following OGD. Then, CCK8 assay western blot assay, and flow cytometry assay verified that upregulation of miR-484 increased viability and inhibited apoptosis of neurons following OGD. Further bioinformatics methods and dual-luciferase reporter assay were applied together to anticipate and certify the interaction between miR-484 and BCL2L13. Finally, cerebral infarct size assessment and TUNEL staining confirmed that overexpression of miR-484 alleviated cerebral ischemia/reperfusion injury in mice, and overexpression of BCL2L13 could abolish the effect of miR-484-suppressed cell apoptosis. All these results suggested that miR-484 alleviates cerebral ischemia/reperfusion injury-induced neuronal apoptosis in mice by targeting apoptosis facilitator BCL2L13.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33656995

RESUMO

The identification of cancer subtypes is of great importance for understanding the heterogeneity of tumors and providing patients with more accurate diagnoses and treatments. However, it is still a challenge to effectively integrate multiple omics data to establish cancer subtypes. In this paper, we propose an unsupervised integration method, named weighted multi-view low rank representation (WMLRR), to identify cancer subtypes from multiple types of omics data. Given a group of patients described by multiple omics data matrices, we first learn a unified affinity matrix which encodes the similarities among patients by exploring the sparsity-consistent low-rank representations from the joint decompositions of multiple omics data matrices. Unlike existing subtype identification methods that treat each omics data matrix equally, we assign a weight to each omics data matrix and learn these weights automatically through the optimization process. Finally, we apply spectral clustering on the learned affinity matrix to identify cancer subtypes. Experiment results show that the survival times between our identified cancer subtypes are significantly different, and our predicted survivals are more accurate than other state-of-the-art methods. In addition, some clinical analyses of the diseases also demonstrate the effectiveness of our method in identifying molecular subtypes with biological significance and clinical relevance.

6.
Phytomedicine ; 84: 153507, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33636577

RESUMO

BACKGROUND: Matrine (Mat), a bitter tastes compounds of derived from leguminosae such as Sophora flavescens and S. subprostrata, commonly used to improve obesity and diabetes. PURPOSE: Our study to demonstrate bitter substances can stimulate the Bitter taste receptors (TAS2Rs) or Calcium-sensing receptor (CaSR) to stimulate the secretion of GLP-1 to promote blood glucose regulation. METHODS: The diabetic mice and intestinal secretory cell model were established to evaluate the Mat on glucose metabolism, intestinal insulin secretion and GLP-1 secretion related substances. To clarify the mechanism of Mat in regulating GLP-1 secretion by immunofluorescence, calcium labeling, siRNA, and molecular docking. RESULTS: The results showed that Mat could significantly improve glucose metabolism and increased insulin and GLP-1 secretion in diabetic mice and increased trisphosphate inositol (IP3) levels by affecting the expression of phospholipase C ß2 (PLCß2) and promote an increase in intracellular Ca2+ levels in STC-1 cells to subsequently stimulate the secretion of GLP-1. Knockdown of the bitter taste receptors mTas2r108, mTas2r137, and mTas2r138 in STC-1 cells by siRNA did could not affect the role of Mat in regulating GLP-1. However, the secretion of GLP-1 by Mat could be significantly inhibited by administration of a CaSR inhibitor or siRNA CaSR. Molecular docking analysis showed that Mat could embed CaSR protein and bind to the original ligand of the egg white at the same amino acid site to play the role of an agonist. CONCLUSION: Matrine is a typical bitter alkaloid could be used as an agonist of CaSR to stimulate the secretion of GLP-1 in the intestine, and it may be used as a potential drug for diabetes treatment.

7.
BMC Cancer ; 21(1): 122, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33546637

RESUMO

BACKGROUND: The relationship between cancer and coagulation has been intensively studied in recent years; however, the effects of coagulation factors on oral squamous cell carcinoma (OSCC) have rarely been reported. This study aimed to investigate the relationship between preoperative D-dimer (DD), fibrinogen (FIB), platelets (PLT) and OSCC, as well as the prognostic value of DD, FIB and PLT in OSCC. METHODS: We retrospectively investigated a total of 202 patients with OSCC treated at Guanghua Hospital of Stomatology, Sun Yat-sen University. Baseline demographic and clinicopathological information as well as both preoperative and postoperative DD, FIB and PLT results were collected from each patient, and patients with primary OSCC were followed up for disease progression, death or the end of the study. The correlations between preoperative DD, FIB, PLT and other clinical features, as well as the therapeutic effect and PFS were analysed statistically, and postoperative DD and surgical parameters were also analysed. RESULTS: Preoperative DD was significantly correlated with T stage, N stage, clinical stage and relapse of OSCC (P = 0.000, 0.001, 0.000 and 0.000, respectively). Univariate Cox regression analyses showed that high preoperative DD predicted poor prognosis in patients with OSCC (HR = 2.1, P = 0.033), while FIB and PLT showed no prognostic values. Postoperative DD was significantly correlated with preoperative DD and surgical type but not the duration of surgery (P = 0.005, 0.001 and 0.244, respectively). CONCLUSION: In this study, we suggested that high preoperative DD level may serve as an indicator for synchronous neck dissection in patients with T1, 2 OSCC, and the elevated DD level might be the marker of disease progression in patient follow up.

8.
Vascular ; : 1708538121990120, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596790

RESUMO

OBJECTIVES: This study was aimed to evaluate the safety and efficacy of endovascular treatment of extracranial carotid artery aneurysms (ECAAs) using self-expandable covered stent grafts. METHODS: All patients with ECAA at a single institution were reviewed from February 2014 to February 2020. Eight consecutive patients (three men, mean age 64.5 years) treated with endovascular repair with self-expandable covered stent graft were retrospectively reviewed. Patient characteristics, angiographic results, and follow-up outcomes were retrospectively recorded. Access to ECAA was gained via a femoral approach or a direct puncture of common carotid artery after surgical exposure because of kinking of the aortic arch and common carotid artery. A self-expandable covered stent graft (Viabahn; W. L. Gore, Flagstaff, AZ) was deployed to exclude the aneurysm. RESULTS: Based on imaging features, there were five peudoaneurysms and three true aneurysms. The technical success rate was 100%. Cerebral protection devices were not used in all the patients during the procedures. Immediate absolute obliteration of the ECAA with no endoleak was documented in all the patients. Perioperative complications included one internal carotid-cavernous sinus fistula, one bleeding at the puncture site, and one stroke. The mean follow-up period was 35.5 months (range, 9-72 months). All the patients were alive, with an obligation rate of 100%. No transient ischemia attack, stroke, or reoccurrence of symptoms was identified during the follow-up period. Radiological examinations identified patency of the stent grafts and revealed no endoleaks, stent fracture, stent migration, or aneurysm rupture. CONCLUSIONS: Endovascular treatment of ECAAs with self-expandable covered stent grafts appears to be a safe and feasible alternative for traditional open surgery, especially in the challenging anatomy and instable physical conditions. Although cerebrovascular accidents can occur as the result of hemodynamic changes during the perioperative period, the minimal alternative can yield satisfactory midterm follow-up clinical outcomes.

9.
Mol Pain ; 17: 1744806921990934, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33590786

RESUMO

Chronic pain is highly prevalent worldwide and severely affects daily lives of patients and family members. Praeruptorin C (Pra-C) is a main active ingredient derived from Peucedanum praeruptorum Dunn, traditionally used as antibechic, anti-bronchitis and anti-hypertension drug. Here, we evaluated the effects of Pra-C in a chronic inflammatory pain mouse model induced by complete Freund's adjuvant (CFA) injection. Pra-C (3 mg/kg) treatment for just 3 days after CFA challenge relieved CFA-induced mechanical allodynia and hindpaw edema in mice. In the anterior cingulate cortex (ACC), Pra-C treatment inhibited microglia activation and reduced levels of proinflammatory cytokines, TNF-α and IL-1ß, and suppressed upregulation of glutamate receptors caused by CFA injection. In addition, Pra-C attenuated neuronal hyperexcitability in ACC of CFA-injected mice. In vitro studies confirmed the analgesic effect of Pra-C was due to its inhibitory ability on microglial activation. In conclusion, Pra-C administration had a certain effect on relieving chronic pain by inhibiting microglial activation, attenuating proinflammatory cytokine releasing and regulating excitatory synaptic proteins in the ACC of the CFA-injected mice.

10.
Int J Biol Macromol ; 172: 429-438, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33454333

RESUMO

In the present study, the effect of transglutaminase (TGase) concentration on the physical and oxidative stabilities of filled hydrogel particles created by biopolymer phase separation was investigated. The results showed that filled hydrogels had relatively smaller particle sizes, higher absolute zeta-potentials, higher interfacial layer thicknesses and lightness values with the increasing of TGase concentration (P < 0.05), as evidenced by the apparent viscosity and viscoelasticity behavior. However, the relatively higher TGase concentration promoted the protein aggregation, which weakens the protection of the surface protein layer, having the negatively impacted the physical stability of filled hydrogels. Microstructural images which obtained via cryo-scanning electron microscopy also verified the above results. In particular, it is noted that filled hydrogels displayed the lowest degrees of lipid and protein oxidation during 10 days of storage (P < 0.05) at TGase concentration of 10 U/g. Prevention against oxidation was attributed mainly to TGase crosslinking of protein molecules on the surface of droplets, which likely provided a denser interface around lipid droplets. Our results indicated that TGase was a favourable agent to crosslink protein on the surface of lipid and improve the physical and oxidative stability of filled hydrogel particles.

11.
J Med Internet Res ; 23(1): e21825, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33417586

RESUMO

BACKGROUND: Internet hospitals in China are being rapidly developed as an innovative approach to providing health services. The ongoing COVID-19 pandemic has triggered the development of internet hospitals that promote outpatient service delivery to the public via internet technologies. To date, no studies have assessed China's internet hospitals during the COVID-19 pandemic. OBJECTIVE: This study aimed to elucidate the characteristics of China's internet hospitals and assess the health service capacity of these hospitals. METHODS: Data on 711 internet hospitals were collected from official websites, the WeChat (Tencent Inc) platform, smartphone apps, and the Baidu search engine until July 16, 2020. RESULTS: As of July 16, 2020, 711 internet hospitals were developed in mainland China. More than half of these internet hospitals (421/711, 59.2%) were established during 2019 (206/711, 29%) and 2020 (215/711, 30.2%). Furthermore, about one-third (215/711, 30.2%) of internet hospitals were established at the beginning of 2020 as an emergency response to the COVID-19 epidemic. The 711 internet hospitals consisted of the following 3 types of hospitals: government-oriented (42/711, 5.91%), hospital-oriented (143/711, 20.11%), and enterprise-oriented internet hospitals (526/711, 73.98%). The vast majority of internet hospitals were traditional hospitals (526/711, 74%). Nearly 46.1% (221/711) of internet hospitals requested doctors to provide health services at a specific web clinic. Most patients (224/639, 35.1%) accessed outpatient services via WeChat. Internet hospitals' consulting methods included SMS text messaging consultations involving the use of graphics (552/570, 96.8%), video consultations (248/570, 43.5%), and telephone consultations (238/570, 41.8%). The median number of available web-based doctors was 43, and the median consultation fees of fever clinics and other outpatient clinics were ¥0 (US $0) per consultation and ¥6 (US $0.93) per consultation, respectively. Internet hospitals have provided various services during the COVID-19 pandemic, including medical prescription, drug delivery, and medical insurance services. CONCLUSIONS: The dramatic increase of internet hospitals in China has played an important role in the prevention and control of COVID-19. Internet hospitals provide different and convenient medical services for people in need.


Assuntos
/epidemiologia , Telemedicina/métodos , /terapia , China/epidemiologia , Estudos Transversais , Análise de Dados , Feminino , Hospitais , Humanos , Internet , Masculino , Pandemias
12.
J Mol Med (Berl) ; 99(2): 273-288, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33388881

RESUMO

NLRP3 inflammasome-driven inflammation represents a key trigger for hepatic fibrogenesis during cholestatic liver injury. However, whether sphingosine 1-phosphate (S1P) plays a role in NLRP3 inflammasome priming and activation remains unknown. Here, we found that the expression of NLRP3 in macrophages and NLRP3 inflammasome activation were significantly elevated in the liver injured by bile duct ligation (BDL). In vitro, S1P promoted the NLRP3 inflammasome priming and activation via S1P receptor 2 (S1PR2) in bone marrow-derived monocyte/macrophages (BMMs). Focusing on BMMs, the gene silencing of Gα12 or Gα13 by specific siRNA suppressed NLRP3 inflammasome priming and pro-inflammatory cytokine (IL-1ß and IL-18) secretion, whereas Gα(i/o) and Gαq were not involved in this process. The MAPK signaling pathways (P38, ERK, and JNK) mediated NLRP3 inflammasome priming and IL-1ß and IL-18 secretion, whereas blockage of PI3K, ROCK, and Rho family had no such effect. Moreover, JTE-013 (S1PR2 inhibitor) treatment markedly reduced NLRP3 inflammasome priming and activation in BDL-injured liver. Collectively, S1P promotes NLRP3 inflammasome priming and pro-inflammatory cytokines (IL-1ß and IL-18) secretion via the S1PR2/Gα(12/13)/MAPK pathway, which may represent an effective therapeutic strategy for liver disease. KEY MESSAGE: • Hepatic NLRP3 expression was significantly elevated in BMMs of BDL-injured mouse liver. • S1P promoted NLRP3 inflammasome priming and activation in BMMs, depending on the S1PR2/Gα(12/13)/MAPK pathway. • Blockade of S1PR2 by JTE-013 reduced NLRP3 inflammasome priming and activation inflammasome in vivo.

13.
J Stroke Cerebrovasc Dis ; 30(3): 105538, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341563

RESUMO

OBJECTS: In this study, we investigated the association between plasma total homocysteine(tHcy) levels and the risk of early hemorrhagic transformation(HT) in patients with acute ischemic stroke(AIS). METHODS: Consecutive hospitalized participants who met the inclusion criteria were enrolled and grouped according to plasma tHcy levels. Participants were divided into a low homocysteine level(L-tHcy) group (<12 µmol/L) and a high homocysteine level group(H-tHcy) (≥ 12 µmol/L). Baseline computed tomography (CT) examination was performed. HT was determined via CT or magnetic resonance imaging within 1 to 3 days after admission. RESULTS: A total of 1858 patients were screened and 1378 patients completed the this study(797 patients in the H-tHcy group and 581 patients in the L-tHcy group). HT incidence was 5.2% (30/581,) in the L-tHcy group and 11.2% (90/797) in the H-tHcy group(P<0.05). Binary logistic regression analysis showed that initial NIHSS score, tHcy levels, treatment with recombinant tissue plasminogen activator thrombolysis, systolic blood pressure on admission, glucose level on admission, smoking status and estimated glomerular filtration rate were independent risk factors for HT. Receiver operating characteristic analysis showed that tHcy level was a moderately sensitive and specific index to predict the incidence of HT, and the optimal cutoff was 16.56 µmol/L (sensitivity 63.3%, specificity 41.3%). CONCLUSION: Our study findings reveal that high plasma tHcy level is one independent risk factor associated with increased risk of early HT in patients with AIS.


Assuntos
Homocisteína/sangue , Hemorragias Intracranianas/epidemiologia , /sangue , Idoso , Biomarcadores/sangue , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Incidência , Hemorragias Intracranianas/diagnóstico por imagem , /epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Regulação para Cima
14.
Rev Port Cardiol ; 40(3): 191-200, 2021 Mar.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33334620

RESUMO

OBJECTIVE: Cardiomyocyte hypertrophy is an important feature of hypertension. However, its molecular underpinnings, especially the signaling cascades, remain unclear. Here we hypothesized that a protein kinase D (PKD)-dependent extracellular signal-regulated kinase 5 (ERK5) pathway was able to regulate downstream myocyte enhancer factor 2D (MEF2D), affecting prohypertrophic responses to angiotensin II (Ang II). METHODS: Neonatal rat cardiomyocytes from 2- to 3-day-old Sprague-Dawley rats were prepared and Western blot, real-time quantitative PCR and immunofluorescence staining were used to assess the activation and translocation of pathway signaling molecules. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) expression and [3H]-leucine (Leu) incorporation were measured to determine cell hypertrophy. RESULTS: Elevated levels of phosphorylated PKD (p-PKD) and ERK5 (p-ERK5) were observed in cardiomyocytes stimulated with Ang II, while silencing protein kinase C epsilon (PKCɛ) resulted in significantly lower levels of p-PKD. Furthermore, Ang II-induced ERK5 activated translocation was mediated by the PKD pathway. Consequently, inhibiting PKCɛ, PKD and ERK5 by siRNA significantly attenuated Ang II-induced MEF2D activation, ANP and BNP mRNA expression, and [3H]-Leu incorporation. CONCLUSIONS: Our studies are the first to show that the PKCɛ/PKD/ERK5/MEF2D pathway plays an important role in the cardiomyocyte hypertrophy response to Ang II.

15.
J Colloid Interface Sci ; 585: 328-336, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33302049

RESUMO

Lithium-sulfur batteries, as a next-generation energy storage system, could deliver much higher energy density than traditional lithium-ion batteries. Although many scientific issues have been well solved, the low-cost and green synthesis of the sulfur host to realize efficient electrochemical conversions between polysulfides and sulfur needs more consideration for commercial application. Herein, Co nanocrystal encapsulated in 3D nitrogen-doped mesoporous carbon (Co@NC) is produced in gram-scale via a simple pressure-cooking strategy by using biomass as raw material. The heterogeneous catalyst was featured by an oval morphology consisting of a tremendous amount of mesopores. The Co nanocrystals in the 3D mesoporous carbon could promote the confinement and fast conversion of polysulfides; simultaneously, the 3D hollow oval morphologies could not only substantially relieve the volume change of the cathode part but also enhance the lithium-ion transportation. Consequently, a sulfur cathode within Co@NC with a sulfur loading of 2.5 mg/cm2 exhibits significantly improved cycle stability with a fade of 0.17% per cycle over 200 cycles. Our works prove the beneficial effects of heterogeneous catalysis in polysulfide conversion reactions and provide a green, facile, scalable, and low-cost synthetic strategy of advanced hollow carbon monolith for high-performance Li-S batteries.

16.
Brief Bioinform ; 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33276376

RESUMO

Disease-gene association through genome-wide association study (GWAS) is an arduous task for researchers. Investigating single nucleotide polymorphisms that correlate with specific diseases needs statistical analysis of associations. Considering the huge number of possible mutations, in addition to its high cost, another important drawback of GWAS analysis is the large number of false positives. Thus, researchers search for more evidence to cross-check their results through different sources. To provide the researchers with alternative and complementary low-cost disease-gene association evidence, computational approaches come into play. Since molecular networks are able to capture complex interplay among molecules in diseases, they become one of the most extensively used data for disease-gene association prediction. In this survey, we aim to provide a comprehensive and up-to-date review of network-based methods for disease gene prediction. We also conduct an empirical analysis on 14 state-of-the-art methods. To summarize, we first elucidate the task definition for disease gene prediction. Secondly, we categorize existing network-based efforts into network diffusion methods, traditional machine learning methods with handcrafted graph features and graph representation learning methods. Thirdly, an empirical analysis is conducted to evaluate the performance of the selected methods across seven diseases. We also provide distinguishing findings about the discussed methods based on our empirical analysis. Finally, we highlight potential research directions for future studies on disease gene prediction.

17.
Front Neurosci ; 14: 870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281538

RESUMO

Epilepsy is a prevalent neurological disorder that threatens human health in the world. The most commonly used method to detect epilepsy is using the electroencephalogram (EEG). However, epilepsy detection from the EEG is time-consuming and error-prone work because of the varying levels of experience we find in physicians. To tackle this challenge, in this paper, we propose a multi-scale non-local (MNL) network to achieve automatic EEG signal detection. Our MNL-Network is based on 1D convolution neural network involving two specific layers to improve the classification performance. One layer is named the signal pooling layer which incorporates three different sizes of 1D max-pooling layers to learn the multi-scale features from the EEG signal. The other one is called a multi-scale non-local layer, which calculates the correlation of different multi-scale extracted features and outputs the correlative encoded features to further enhance the classification performance. To evaluate the effectiveness of our model, we conduct experiments on the Bonn dataset. The experimental results demonstrate that our MNL-Network could achieve competitive results in the EEG classification task.

18.
Front Microbiol ; 11: 592524, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304340

RESUMO

Autophagy plays an important role in cell growth and development. The autophagy-related gene atg4 encodes a cysteine protease, which can cleave the carboxyl terminus of Atg8, thus plays a role in autophagosome formation in yeast and filamentous fungi. Arthrobotrys oligospora is well known for producing special trapping-devices (traps) and capturing nematodes. In this study, two ΔAolatg4 mutants were generated using targeted gene replacement and were used to investigate the biological functions of autophagy in A. oligospora. Autophagic process was observed using the AoAtg8-GFP fusion protein. The mutants showed a defective in hyphal growth and sporulation and were sensitive to chemical stressors, including menadione and Congo red. The spore yield of the ΔAolatg4 mutants was decreased by 88.5% compared to the wild type (WT), and the transcript levels of six sporulation-related genes, such as abaA, fluG, brlA, and wetA, were significantly downregulated during the conidiation stage. Deletion of Aolatg4 also affected the cell nuclei and mycelial septal development in A. oligospora. Importantly, autophagosome formation and the autophagic process were impaired in the ΔAolatg4 mutant. Moreover, the ΔAolatg4 mutant lost its ability to form mature traps. Our results provide novel insights into the roles of autophagy in A. oligospora.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33373072

RESUMO

Endohedral clusterfullerenes exhibit unique chemical properties due to intramolecular electron transfer of the encaged metal cluster to the outer fullerene cages. We report the synthesis of two Sc3 N@D3h -C78 monoadducts 2 a and 2 b through the 1,3-dipolar reaction of Sc3 N@D3h -C78 with carbonyl ylide bearing anomalous cis-conformation regioselectivity. The molecular structures of these monoadducts are unambiguously confirmed by single-crystal X-ray crystallography, revealing that both 2 a and 2 b have cis-conformations with the furan moiety grafted via [6,6]-closed addition patterns. Under the same conditions, the control reaction of C60 with carbonyl ylide affords two monoadducts 3 a and 3 b, which exhibit cis- and trans-conformations, respectively, with [6,6]-closed addition patterns. According to theoretical calculations, the exclusive formation of the cis-only Sc3 N@D3h -C78 monoadducts is a consequence of conjunct effects of thermodynamic stability of adducts, the reactivity of the addition site, and the cis-dipole intermediate from trans 1.

20.
Semin Cancer Biol ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33242577

RESUMO

Acute myeloid leukemia (AML) is the most frequently diagnosed acute leukemia, and its incidence increases with age. Although the etiology of AML remains unknown, exposure to genotoxic agents or some prior hematologic disorders could lead to the development of this condition. The pathogenesis of AML involves the development of malignant transformation of hematopoietic stem cells that undergo successive genomic alterations, ultimately giving rise to a full-blown disease. From the disease biology perspective, AML is considered to be extremely complex with significant genetic, epigenetic, and phenotypic variations. Molecular and cytogenetic alterations in AML include mutations in those subsets of genes that are involved in normal cell proliferation, maturation and survival, thus posing significant challenge to targeting these pathways without attendant toxicity. In addition, multiple malignant cells co-exist in the majority of AML patients. Individual subclones are characterized by unique genetic and epigenetic abnormalities, which contribute to the differences in their response to treatment. As a result, despite a dramatic progress in our understanding of the pathobiology of AML, not much has changed in therapeutic approaches to treat AML in the past four decades. Dose and regimen modifications with improved supportive care have contributed to improved outcomes by reducing toxicity-related side effects. Several drug candidates are currently being developed, including targeted small-molecule inhibitors, cytotoxic chemotherapies, monoclonal antibodies and epigenetic drugs. This review summarizes the current state of affairs in the pathobiological and therapeutic aspects of AML.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...