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1.
Curr Eye Res ; : 1-8, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33645355

RESUMO

Purpose: To investigate the prevalence and clinical characteristics of myelinated retinal nerve fibre (MRNF) in a large teleophthalmology system.Methods: All records between January 2015 and December 2015 from Daheng Prust teleophthalmology system were reviewed by 2 ophthalmologists independently. MRNF was classified into continuous group and discontinuous group according to the relationship between MRNF patches and optic disc. The number, total area and location of MRNF patches were analysed. Concomitant ocular diseases were documented.Results: Out of 51469 subjects, MRNF was detected in 304 eyes of 263 subjects with a prevalence rate of 0.51 ± 7.1% per subject and 0.30 ± 5.4% per eye. Among 304 eyes with MRNF, 239 (78.6%) eyes were in continuous group and 65 (21.4%) eyes were in discontinuous group. Single MRNF patch was found in 249 (81.9%) eyes and multiple MRNF patches were found in 55 (18.1%) eyes. MRNF of small size was found in 150 (49.3%) eyes. The ratios of multiple MRNF patches and small-sized MRNF in the continuous group were significantly higher than those in the discontinuous group (P = .014 and P < .001). In continuous group, the MRNF patches were located most frequently in the superior region (68.6%) of the optic disc; In discontinuous group, the MRNF patches were located most frequently in the inferotemporal region (38.5%) of the retina. Epiretinal membrane (12 eyes, 3.9%) was the most common concomitant ocular disease.Conclusion: MRNF is uncommon in China. MRNF usually presents unilaterally and as a single small whitish patch that is connected with optic disc.

2.
BMC Gastroenterol ; 21(1): 84, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622256

RESUMO

BACKGROUND: Hepatic cavernous hemangioma is the most common type of benign liver tumor. Although ruptures and hemorrhages of hepatic hemangioma are rare complications, they are associated with high mortality. Most practitioners only pay more attention to abdominal hemorrhages caused by the rupture of hepatic hemangiomas. However, spontaneous intracapsular hemorrhages can often be neglected and poorly understood. CASE PRESENTATION: A 65-year-old man was referred to our institution with right upper quadrant pain, which had occurred suddenly and without a history of recent trauma. The blood test results were normal. Magnetic resonance imaging (MRI) of the abdomen showed a cystic mass in the right liver lobe. Considering the possibility of hepatic cystadenoma with hemorrhage, the patient underwent a right hepatic lobectomy. The pathological findings unexpectedly revealed intratumoral hemorrhage of hepatic hemangioma. The patient recovered well and was discharged eight days after surgery. CONCLUSIONS: Intracapsular hemorrhage of hepatic cavernous hemangioma is challenging to diagnose and has a high potential risk of rupture. MRI is beneficial for diagnosing subacute internal hemorrhage cases, and it is recommended to undergo surgery for patients with a definitive diagnosis.

3.
J Leukoc Biol ; 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33464650

RESUMO

The objective of this study was to find the role of LncRNA SNHG12 in the regulation of hypertensive vascular endothelial injury. LncRNA SNHG12 and miR-25-3p expression were detected by quantitative RT-PCR. Protein levels of Sirtuin 6 (SIRT6), endothelial cell (EC) senescence markers p16 and p21, and EC marker CD31 were measured by Western blot. The apoptosis of HUVECs was detected by flow cytometry. The binding between LncRNA SNHG12 and miR-25-3p was verified by dual luciferase reporter gene assay and RNA pull-down assay. As a result, LncRNA SNHG12 was down-regulated in aortic primary ECs isolated from Ang II-induced hypertensive mice and 1 kidney/deoxycorticosterone acetate/salt-induced hypertensive mice. In Ang II-treated HUVECs, the expression level of SNHG12 was reduced and the overexpression of SNHG12 inhibited EC senescence markers p16 and p21 expressions, the apoptosis of HUVECs, and caspase-3 activity. Further investigation confirmed that LncRNA SNHG12 bound to miR-25-3p, and negatively regulated miR-25-3p expression. MiR-25-3p directly targeted SIRT6 and negatively regulated SIRT6 expression. In addition, SNHG12 overexpression inhibited Ang II-induced HUVECs injury through regulating miR-25-3p. Finally, in vivo experiments showed LncRNA SNHG12 overexpression alleviated vascular endothelial injury in Ang II-induced hypertensive mice. In conclusion, LncRNA SNHG12 alleviates vascular endothelial injury induced by hypertension through miR-25-3p/SIRT6 pathway.

4.
Breast Cancer Res Treat ; 182(1): 21-33, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32415497

RESUMO

PURPOSE: Previous studies have indicated that transient receptor potential (TRP) channels can influence cancer development. The TRPC subfamily consists of seven subtypes, TRPC1 - TRPC7. Interestingly, the expression levels of TRPC1 have been shown to be totally different in different breast cancer cell lines. Nevertheless, the underlying mechanism remains unknown. In this study, we explore the significance of TRPC1 expression in breast cancer. METHODS: Immunohistochemical TRPC1 staining was performed in 278 samples. TRPC1 expression in different breast tissues were examined. Then, the influence of TRPC1 on migration, invasion and proliferation was explored. We analyzed the protein of TRPC1 by Western blot to prove which pathway may be involved in. Finally, we use online database to predict the prognosis of TRPC1 in breast cancer. RESULTS: Through immunohistochemistry and in vitro experiments, we found that the expression level of TRPC1 was higher in breast cancer cells as compared with that in normal breast epithelial cells. Moreover, the expression level of TRPC1 was different between estrogen receptor-positive (ER +) and -negative (ER -) breast cancer. It was shown that TRPC1 inhibited MCF7 cell proliferation, migration, and invasion in vitro. Western blotting revealed that TRPC1 inhibited the PI3K/AKT pathway and epithelium-mesenchymal transformation, leading to subsequent inhibition of cell proliferation and metastasis. In luminal A and luminal B patients, those with high TRPC1 expression had a better prognosis. On the contrary, in basal-like and triple-negative breast cancer (TNBC) subtypes, patients with high-TRPC1 expression had a worse prognosis. CONCLUSIONS: We confirmed that TRPC1 was high expression in breast cancer. Overexpression of TRPC1 inhibits proliferation and migration of ER + breast cancer and gives a better prognosis by inhibiting PI3K/AKT pathway activation. TRPC1 may be an independent prognostic predictor in breast cancer patients.

5.
Phys Chem Chem Phys ; 22(17): 9349-9361, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32309835

RESUMO

The fundamental understanding of the cooperativity of a Brønsted acid together with its anion for cellulose conversion in an aqueous solution is limited at present, in which cellobiose has usually been regarded as a bridge that connects monosaccharides and cellulose. The mechanism of ß-cellobiose conversion to 5-hydroxymethylfurfural (HMF) catalyzed by a Brønsted acid (H3O+) accompanied by counteranions in an aqueous solution has been studied using quantum chemical calculations at the M06-2X/6-311++G(d,p) level under a polarized continuum model (PCM-SMD). For the formation of the first HMF from cellobiose, there are three reaction pathways, i.e., through cellobiulose and glycosyl-HMF (C/H), through cellobiulose and fructose (C/F/H), and through glucose (C/G/H). For these three reaction pathways, the rate-determining steps are associated with the intramolecular [1,2]-H shift in the aldose-ketose tautomerization. C/H is the thermodynamically predominant pathway, while C/G/H is the kinetically dominant pathway. From cellobiose, the origin of the first HMF results kinetically from a small proportion of both C/H and C/F/H and from a large proportion of C/G/H. For the role of the counteranion in the catalytic activity of H3O+, the halide anions (Cl- and Br-) act as promoters, whereas both NO3- anions and carboxylate-containing anions behave as inhibitors. The roles of these anions in ß-cellobiose conversion to HMF can be correlated with their electrostatic potential and atomic number, which may cause a decrease in the relative enthalpy energy and the value of entropy on interacting with the cation moiety. These insights may advance the novel design of sustainable conversion systems for cellulose conversion into HMF.

6.
J Clin Invest ; 130(3): 1252-1270, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32039918

RESUMO

Current antiangiogenic therapy is limited by its cytostatic property, scarce drug delivery to the tumor, and side toxicity. To address these limitations, we unveiled the role of ZEB1, a tumor endothelium-enriched zinc-finger transcription factor, during tumor progression. We discovered that the patients who had lung adenocarcinomas with high ZEB1 expression in tumor endothelium had increased prevalence of metastases and markedly reduced overall survival after the diagnosis of lung cancer. Endothelial ZEB1 deletion in tumor-bearing mice diminished tumor angiogenesis while eliciting persistent tumor vascular normalization by epigenetically repressing TGF-ß signaling. This consequently led to improved blood and oxygen perfusion, enhanced chemotherapy delivery and immune effector cell infiltration, and reduced tumor growth and metastasis. Moreover, targeting vascular ZEB1 remarkably potentiated the anticancer activity of nontoxic low-dose cisplatin. Treatment with low-dose anti-programmed cell death protein 1 (anti-PD-1) antibody elicited tumor regression and markedly extended survival in ZEB1-deleted mice, conferring long-term protective anticancer immunity. Collectively, we demonstrated that inactivation of endothelial ZEB1 may offer alternative opportunities for cancer therapy with minimal side effects. Targeting endothelium-derived ZEB1 in combination with conventional chemotherapy or immune checkpoint blockade therapy may yield a potent and superior anticancer effect.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco/deficiência , Animais , Antineoplásicos Imunológicos/farmacologia , Cisplatino/farmacologia , Endotélio/imunologia , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/imunologia , Deleção de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/imunologia , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco/imunologia
7.
Toxicol Appl Pharmacol ; 389: 114882, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31953203

RESUMO

Pulmonary fibrosis is a prototypic chronic progressive lung disease with high morbidity and mortality worldwide. Novel effective therapeutic agents are urgently needed owing to the limited treatment options in clinic. Herein, nagilactone D (NLD), a natural dinorditerpenoid obtained from Podocarpus nagi, was found to suppress transforming growth factor-ß1 (TGF-ß1)-mediated fibrotic process in vitro and bleomycin (BLM)-induced pulmonary fibrosis in vivo. NLD attenuated TGF-ß1-induced expression of fibrotic markers including type I and III collagen, fibronectin, α-SMA, and CTGF in human pulmonary fibroblasts (WI-38 VA-13 and HLF-1 cells). Mechanism study indicated that NLD suppressed TGF-ß1-induced up-regulation of TßR I, and Smad2 phosphorylation, nuclear translocation, and transcriptional activation. Moreover, NLD ameliorated BLM-induced histopathological abnormalities in the lungs of experimental fibrotic mice, suppressed synthesis of relative fibrotic markers and fibroblast-to-myofibroblast transition, as well as BLM-induced up-regulation of TßR I expression and Smad signaling in mouse lungs. These data collectively support NLD to be a potential therapeutic agent for pulmonary fibrosis.


Assuntos
Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Proteína Smad2/metabolismo , Terpenos/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Biomarcadores/metabolismo , Bleomicina/farmacologia , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Fibrose Pulmonar/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Angew Chem Int Ed Engl ; 58(36): 12705-12710, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31297923

RESUMO

Exploring dynamic bonds and their applications in fabricating dynamic materials has received great attention. A photoinduced [2]rotaxane-based dynamic mechanical bond (DMB) features visible-light-triggered dynamic bonding behavior that is essentially distinguished from conventional dynamic chemical bonds. In this DMB, a photoisomerizable ortho-fluoroazobenzene unit is introduced as a steric-controllable stopper, the visible-light-induced dynamic wagging movement of which enables the photoregulated threading of the macrocycle. This allows reversible in situ de-/reforming of the mechanical bond without involving dynamic chemical linkage. The DMB-cross-linked polymeric gel shows interesting photoinduced degradation behavior upon visible light irradiation. Benefiting from the distinctive dual dynamic nature of reversible bonding behavior and mechanical interlocked structure, this DMB is expected to serve as a new type of dynamic bond that can be applied in designing dynamic soft materials.

9.
Nat Commun ; 10(1): 3210, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324807

RESUMO

Accumulating evidence indicates that the zinc-finger transcription factor ZEB1 is predominantly expressed in the stroma of several tumours. However, the role of stromal ZEB1 in tumour progression remains unexplored. In this study, while interrogating human databases, we uncover a remarkable decrease in relapse-free survival of breast cancer patients expressing high ZEB1 levels in the stroma. Using a mouse model of breast cancer, we show that ZEB1 inactivation in stromal fibroblasts suppresses tumour initiation, progression and metastasis. We associate this with reduced extracellular matrix remodeling, immune cell infiltration and decreased angiogenesis. ZEB1 deletion in stromal fibroblasts increases acetylation, expression and recruitment of p53 to FGF2/7, VEGF and IL6 promoters, thereby reducing their production and secretion into the surrounding stroma. Importantly, p53 ablation in ZEB1 stroma-deleted mammary tumours sufficiently recovers the impaired cancer growth and progression. Our findings identify the ZEB1/p53 axis as a stroma-specific signaling pathway that promotes mammary epithelial tumours.


Assuntos
Fibroblastos/metabolismo , Neoplasias Epiteliais e Glandulares/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Animais , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Matriz Extracelular/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 7 de Crescimento de Fibroblastos/metabolismo , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença/genética , Humanos , Interleucina-6 , Masculino , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Knockout , Recidiva Local de Neoplasia/metabolismo , Neoplasias Experimentais , Neoplasias Epiteliais e Glandulares/patologia , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
10.
J Exp Clin Cancer Res ; 38(1): 134, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30898152

RESUMO

BACKGROUND: The transforming growth factor ß (TGFß) and bone morphogenetic protein (BMP) signaling pathways are both constitutively activated in triple-negative breast cancer (TNBC). We are interested in isolating the naturally-derived small-molecule inhibitor that could simultaneously targeting TGFß/BMP pathways and further studying its anti-proliferative/-metastatic effects as well as the underlying mechanisms in multiple tumor models. METHODS: Multiple in vitro cell-based assays are used to examine the compound's inhibitory efficacy on TNBC cell growth, stemness, epithelial-mesenchymal transition (EMT), invasion and migration by targeting TGFß/BMP signaling pathways. Transgenic breast cancer mouse model (MMTV-PyMT), subcutaneous xenograft and bone metastasis models are used to examine ZL170's effects on TNBC growth and metastasis potentials in vivo. RESULTS: ZL170 dose-dependently inhibits cell proliferation, EMT, stemness, invasion and migration in vitro via specifically targeting canonical TGFß/BMP-SMADs pathways in TNBC cells. The compound significantly hinders osteolytic bone metastasis and xenograft tumor growth without inflicting toxicity on vital organs of tumor-bearing nude mice. ZL170 strongly inhibits primary tumor growth and lung metastases in MMTV-PyMT transgenic mice. ZL170-treated tumors exhibit impaired TGFß/BMP signaling pathways in both epithelial and stromal compartments, thereby creating a suppressive tumor microenvironment characterized by reduced extracellular matrix deposition and decreased infiltration of stromal cells. CONCLUSIONS: ZL170 inhibits tumor EMT, stemness and metastasis and could be further developed as a potent anti-metastatic agent used in combination with cytotoxic drugs for treatment of TNBC and other advanced metastatic cancers.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Oxindois/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Feminino , Humanos , Camundongos , Camundongos Nus , Camundongos Transgênicos , Células-Tronco Neoplásicas/metabolismo , Oxindois/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
MycoKeys ; (46): 119-150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30814907

RESUMO

Neostagonosporellasichuanensis sp. nov. was found on Phyllostachysheteroclada collected from Sichuan Province in China and is introduced in a new genus Neostagonosporella gen. nov. in this paper. Evidence for the placement of the new taxon in the family Phaeosphaeriaceae is supported by morphology and phylogenetic analysis of a combined LSU, SSU, ITS and TEF 1-α DNA sequence dataset. Maximum-likelihood, maximum-parsimony and Bayesian inference phylogenetic analyses support Neostagonosporella as a distinct genus within this family. The new genus is compared with related genera of Phaeosphaeriaceae and full descriptions and illustrations are provided. Neostagonosporella is characterised by its unique suite of characters, such as multiloculate ascostromata and cylindrical to fusiform, transversely multiseptate, straight or curved ascospores, which are widest at the central cells. Conidiostromata are multiloculate, fusiform to long fusiform or rhomboid, with two types conidia; macroconidia vermiform or subcylindrical to cylindrical, transversely multiseptate, sometimes curved, almost equidistant between septa and microconidia oval, ellipsoidal or long ellipsoidal, aseptate, rounded at both ends. An updated phylogeny of the Phaeosphaeriaceae based on multigene analysis is provided.

12.
Iran J Public Health ; 48(1): 112-119, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30847318

RESUMO

Background: This study aimed to evaluate the characteristics of faculty and research activities of basic stem cell research groups in China. Methods: A questionnaire was administered to persons who knew the information among 46 basic stem cell research groups in China. Multiple linear regression models and repeated-measures analyses of variance were used. Repeated-measures analyses of variance were used. Results: Of the 46 groups, 39.1% did not have any faculty recruited from abroad from 2009 to 2013, 37.0% did not have any faculty with junior-level title, 34.8% had ≤25.0% faculty with either M.D. or Ph.D. degree. Papers published in SCI journals per faculty and having faculty recruited from abroad were positively associated with research funding per faculty. The groups with faculty recruited from abroad had significantly higher research funding per faculty over time compared with the group without faculty recruited from abroad. Repeated-measures analyses of variance showed the group with faculty recruited from abroad had significantly higher research funding per faculty over time compared with the group without faculty recruited from abroad. Conclusion: To increase the development of basic stem cell research, some characteristics of human resources should be improved, and the groups should recruit more faculty with overseas experience.

13.
Int Heart J ; 60(2): 296-302, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30799382

RESUMO

Recent reports show that an early repolarization pattern (ERP) is associated with a higher incidence of sudden cardiac death in patients with obstructive coronary artery disease (CAD). Sporadic case studies have pointed out that ERP might be related to obstructive CAD.In consecutive patients who had undergone coronary angiography, we investigated the relationship between ERP and obstructive CAD by evaluating its association with coronary artery stenosis.The study population consisted of 3785 patients (59.9% men; mean age 63.1 years) with or without obstructive CAD. Adjusting for major cardiovascular risk factors, ERP was significantly associated with obstructive CAD (adjusted odds ratio (OR): 2.24 [95% CI 1.70-2.95]) with an incremental predictive value (ROC AUC 0.76 versus 0.71, P = 0.02; NRI 55.3%, P < 0.001; IDI = 0.05, P = 0.008), specifically in subjects with low risk and intermediate risk. ERP also significantly improved the predictive value for multi-vessel disease (AUC: 0.77 versus 0.72, P = 0.02 for two-vessel disease; 0.79 versus 0.73, P = 0.04 for three-vessel disease). ERP was consistently associated with stenoses of 3 main coronary arteries.ERP is associated with significant increased risk for obstructive CAD.Further studies are warranted to confirm our results and to elucidate the specific pathogenic mechanisms.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana , Estenose Coronária , Vasos Coronários , Morte Súbita Cardíaca , Eletrocardiografia , China/epidemiologia , Angiografia Coronária/estatística & dados numéricos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiopatologia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia/métodos , Eletrocardiografia/estatística & dados numéricos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Índice de Gravidade de Doença
14.
Phys Chem Chem Phys ; 21(7): 3795-3804, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30714064

RESUMO

The selective removal of oxygen from 5-hydroxymethylfurfural (HMF) is challenging for the effective utilization of biomass. The catalytic mechanisms of palladium acetate toward the conversion of HMF to furfuryl alcohol (FFA), 5-methylfurfural (5-MF) and 2,5-dihydroxymethyl furan (DHMF) have been theoretically investigated. The decarbonylation of HMF to FFA includes (i) migratory extrusion, (ii) metal-acetate-co-assisted deprotonation, (iii) decarbonylation, (iv) metal-assisted deprotonation, and (v) migratory extrusion and catalyst regeneration. Both hydrogenation and deoxidation of HMF with HCOOH as the H-source involve (i) migratory extrusion, (ii) oxidative addition, (iii) reductive elimination, (iv) metal-assisted deprotonation, and (v) migratory extrusion and catalyst regeneration. The C-H bond cleavage is the crucial reaction step, in which the metal-acetate-co-assisted deprotonation is kinetically more preferable than the oxidative addition. Both FFA and DHMF are kinetically superior to 5-MF. In terms of selectivity, increasing the temperature is beneficial to decarbonylation and decreasing the temperature is advantageous to hydrogenation. The present finding provides molecular-level insight into the functions of both the metal-center and coordinated-ligand in the Pd(OAc)2 catalyst, which may drive the novel design of catalytic systems toward both decarbonylation and hydrogenation reactions.

15.
Int J Syst Evol Microbiol ; 69(3): 811-815, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30688630

RESUMO

A facultatively anaerobic and Gram-negative bacterium, designated strain PLHSC7-2T, was isolated from the gut of sea cucumber Apostichopusjaponicus that had been collected from the coastal area of Yantai, China. The cells were rod-shaped and motile by means of polar flagella. The novel isolate grew optimally at 28-30 °C, in the presence of 2.0-3.0 % (w/v) NaCl and at pH 7.0-7.5. The sole respiratory quinone was Q-8 and the major fatty acids were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C17 : 0. The predominant polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain PLHSC7-2T was phylogenetically affiliated with the genus Motilimonas, and exhibited sequence similarity of 96.2 % toMotilimonas eburnea YH6T. The DNA G+C content was 45.5 mol%. On the basis of phenotypic , phylogenetic and genetic distinctiveness, strain PLHSC7-2T (=MCCC 1K03522T=KCTC 62589T) was classified as a novel species within the genus Motilimonas, for which the name Motilimonas pumila sp. nov. is proposed.


Assuntos
Gammaproteobacteria/classificação , Filogenia , Stichopus/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
16.
Cell Physiol Biochem ; 51(3): 1301-1312, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30481776

RESUMO

BACKGROUND/AIMS: Early repolarization syndrome (ERS) has been recently recognized as early repolarization pattern with idiopathic ventricular fibrillation. However, the genetic background of ERS has not been fully understood. METHODS: A Chinese family with sudden cardiac death associated with ERS was investigated. Direct sequencing of ERS susceptibility genes was performed on the proband and family members. Whole-cell patch-clamp methods were used to characterize the mutant channel expressed in HEK 293 cells. RESULTS: One missense mutation (p. K801T) was found in the hERG (KCNH2 gene) by the direct sequencing of candidate genes. Whole cell voltage clamp studies of the K801T mutation in HEK 293 cells demonstrated a 1.5-fold increase in maximum steady state current (37.2±7.3 vs 20.3±4.4 pA/pF) that occurred at a 20 mV more positive potential compared to the wild type channels. The voltage dependence of inactivation was significantly shifted in the positive voltage direction (WT -59.5±1.4 vs K801T -44.3±1.2 mV). Kinetic analysis revealed slower inactivation rates of K801T, but faster rates of activation and deactivation. The hERG channel blockers tested inhibited K801T-hERG channel in concentration response, and the potencies of these drugs can be rank-ordered as follows: quinidine> disopyramide> sotalol> flecainide. CONCLUSION: Our study indicated that the K801T mutation caused the gain of function of hERG channels that may account for the clinical phenotype of ERS. Quinidine and disopyramide could improve the function of K801T-hERG mutant channel, and may be therapeutic options for patients with the K801T hERG mutation.


Assuntos
Canal de Potássio ERG1/genética , Mutação de Sentido Incorreto , Fibrilação Ventricular/genética , Adulto , Morte Súbita Cardíaca/etiologia , Células HEK293 , Heterozigoto , Humanos , Masculino , Linhagem , Fibrilação Ventricular/complicações
17.
Opt Lett ; 43(22): 5599-5602, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30439905

RESUMO

We demonstrate a 266 nm ultraviolet (UV) picosecond laser by fourth-harmonic generation of a Nd:YAG laser with a 5.4 mm thick NaSr3Be3B3O9F4 (NSBBF) crystal. A maximum output power exceeding 1 W at 266 nm was obtained (the highest output power being 1.6 W), corresponding to a conversion efficiency of 10.3%. The stability measurements on the NSBBF crystal with a fluctuation of 3.34% at 200 mW within 1 h indicate that it is a promising UV nonlinear optical material for practical applications. In addition, for the first time, to the best of our knowledge, we measured the effective nonlinear coefficient of NSBBF crystal at 266 nm and compared it with that of ß-BaB2O4 crystal.

18.
J Cell Mol Med ; 22(11): 5639-5647, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30160358

RESUMO

BACKGROUND: Abnormal cardiac ion channels current, including transient outward potassium current (Ito ), is associated with early repolarization syndrome (ERS). Previous studies showed that mutations in SCN1Bß both to increase the Ito current and to decrease the sodium current. Yet its role in ERS remains unknown. OBJECTIVE: To determine the role of mutations in the SCN1Bß subunits in ERS. METHODS: We screened for mutations in the SCN1B genes from four families with ERS. Wild-type and mutant SCN1Bß genes were co-expressed with wild-type KCND3 in human embryonic kidney cells (HEK293). Whole-cell patch-clamp technique and co-immunoprecipitation were used to study the electrophysiological properties and explore the underlying mechanisms. RESULTS: S248R and R250T mutations in SCN1Bß were detected in 4 families' probands. Neither S248R nor R250T mutation had significant influence on the sodium channel current density (IN a ) when co-expressed with SCN5A/WT. Co-expression of KCND3/WT and SCN1Bß/S248R or SCN1Bß/R250T increased the transient outward potassium current Ito by 27.44% and 199.89%, respectively (P < 0.05 and P < 0.01, respectively) when compared with SCN1Bß/WT. Electrophysiological properties showed that S248R and R250T mutations decreased the steady-state inactivation and recovery from inactivation of Ito channel. Co-immunoprecipitation study demonstrated an increased association between SCN1Bß mutations and Kv4.3 compared with SCN1Bß/WT (P < 0.05 and P < 0.01, respectively). CONCLUSION: The S248R and R250T mutations of SCN1Bß gene caused gain-of-function of Ito by associated with Kv4.3, which maybe underlie the ERS phenotype of the probands.


Assuntos
Morte Súbita Cardíaca/patologia , Coração/fisiopatologia , Canais de Potássio Shal/genética , Subunidade beta-1 do Canal de Sódio Disparado por Voltagem/genética , Adulto , Idoso , Animais , Eletrofisiologia , Feminino , Predisposição Genética para Doença , Células HEK293 , Coração/diagnóstico por imagem , Humanos , Masculino , Potenciais da Membrana , Mutação/genética , Técnicas de Patch-Clamp , Transfecção
19.
Chem Commun (Camb) ; 54(67): 9356-9359, 2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30079425

RESUMO

Photochromic [2]rotaxanes with bidirectional photoswitchability were fabricated, whose colored states exhibit remarkable visible-light and thermal stabilities as revealed by systematically spectroscopic investigations.

20.
Chem Asian J ; 13(19): 2818-2823, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-29975456

RESUMO

The development of artificial self-assembling systems with dynamic photo-regulation features in aqueous solutions has drawn great attention owing to the potential applications in fabricating elaborate biological materials. Here we demonstrate the fabrication of water-soluble cucurbit[8]uril (CB[8])-mediated supramolecular polymers by connecting the fluorinated azobenzene (FAB) containing monomers through host-enhanced heteroternary π-π stacking interactions. Benefiting from the unique visible-light-induced E→Z photoisomerization of the FAB photochromophores, the encapsulation behaviors between the CB[8] macrocycle and the monomers could be regulated upon visible light irradiation, resulting in the depolymerization of such CB[8]-mediated supramolecular polymers.

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