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1.
Front Psychol ; 12: 783869, 2021.
Article in English | MEDLINE | ID: mdl-35069366

ABSTRACT

Reading comprehension is never considered a simple task in linguists' views as it requires a full set of linguistic knowledge, such as word decoding, understanding syntactic and morphological structures, and deriving proper meanings from these structures in a given context. Bearing the simple view of reading, the primary goal of this study is to explore whether the split presentation of Chinese splittable compounds influences the recognition of the compounds in second language (L2) Chinese reading comprehension, and how the reading skills, i.e., word decoding and linguistic comprehension, cooperate to complete this reading comprehension task. Splittable compounds (SCs) in Chinese are typically verbs composed of two constituents with limited separability. The separable property of SCs and their vague morpho-syntactic status are supposed to cause difficulties for L2 Chinese learners in recognizing the compounds. Especially for those whose native language manifests lexical integrity, the split presentation of the compounds may invite the L2 Chinese readers to process them with a mechanism different from that for their non-split forms. To the best of our knowledge, the efforts on investigating this issue are insufficient. In this study, 27 Spanish speaking L2 Chinese learners were invited to complete tasks including reading and interpreting 6 selected SCs in the split and non-split forms, rating their familiarities with each SC and reporting the syntactic category of the SCs based on their existing linguistic knowledge. The results, showed that the split presentation of SCs did cause challenges for L2 Chinese learners in recognizing the compounds in the reading process, regardless of their Chinese proficiencies. The L2 Chinese participants performed significantly worse in recognizing split SCs in salient Verb-Object structures than recognizing those in unsalient Verb-Object structures. These findings underscore the importance of linguistic comprehension in L2 Chinese in-text word reading comprehension and suggest words as the basic processing units.

3.
Ann Vasc Surg ; 48: 214-221, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29197611

ABSTRACT

BACKGROUND: To investigate whether angiopoietin-1 (Ang-1) could regulate the endothelial progenitor cells (EPCs) survival and the effect of accelerating intra-aneurysmal organization and occlusion of the aneurysm neck. METHODS: EPCs were isolated from Wistar rats. EPCs were cultured and transfected with lentivirus-Ang-1-endothelial progenitor cells (Ang-1-EPCs) and lentivirus-NC-endothelial progenitor cells (NC-EPCs). The effects of Ang-1 on viability and functioning of EPCs were explored via tube formation, migration, and MTT (3-[4,5-dimethylthiazolyl-2]-2,5-diphenyltetrazolium bromide) assays. Eighteen Wistar rats were randomly allocated into 3 groups. Eighteen bare coils were inserted into the ligated external carotid artery (ECA) sacs of rats. The ECA sacs were removed 2 weeks after the coils were implanted and examined by histology assay. RESULTS: Ang-1 significantly promoted EPCs tube formation, migration, and proliferation ability in vitro. Histology analyses revealed that the organized areas in the ECA sacs in the Ang-1-EPCs group are higher than NC-EPCs group and control group at 2 weeks. Immunofluorescence revealed that organized tissues were characterized by an accumulation of cells positive for α-smooth muscle actin-positive cells in aneurysm sacs. CONCLUSIONS: Overexpression of Ang-1 enhanced the tube formation, migration, and proliferation ability of EPCs. Ang-1 gene-modified EPCs accelerated organization within the aneurysms and occlusion of aneurysm neck. Transplantation of Ang-1-transfected EPCs may be a new method for the treatment of aneurysm.


Subject(s)
Aneurysm/surgery , Angiopoietin-1/biosynthesis , Carotid Artery Diseases/surgery , Carotid Artery, External/metabolism , Endothelial Progenitor Cells/transplantation , Neovascularization, Physiologic , Actins/metabolism , Aneurysm/metabolism , Aneurysm/pathology , Angiopoietin-1/genetics , Animals , Carotid Artery Diseases/metabolism , Carotid Artery Diseases/pathology , Carotid Artery, External/pathology , Carotid Artery, External/surgery , Cell Movement , Cell Proliferation , Cell Survival , Cells, Cultured , Disease Models, Animal , Endothelial Progenitor Cells/metabolism , Ligation , Rats, Wistar , Signal Transduction , Time Factors , Up-Regulation
4.
Exp Ther Med ; 14(5): 3961-3970, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29067093

ABSTRACT

The present study reports the effect of successful treatment of cerebral venous sinus thrombosis (CVST) with stent retriever thrombectomy combined with local thrombolytic therapy. Medical records of 29 patients were retrospectively analyzed following a diagnosis of CVST with magnetic resonance venography (MRV) or digital subtraction angiography (DSA). Systemic anticoagulation was the initial treatment in all patients following admission. In group A, stent retriever thrombectomy combined with local thrombolytic therapy was performed on 14 patients who met the criteria of endovascular therapy. Stent-assisted angioplasty was also performed when patients presented with venous sinus stenosis. A total of 15 patients in group B received systemic anticoagulant treatment. Subsequently, warfarin was administered orally for 3 to 12 months as a continuous anticoagulant therapy. International normalized ratio was monitored when patients were receiving anticoagulant therapy. Additionally, clinical presentation, decision to escalate therapy, recanalization, Glasgow Coma Scale, modified Rankin Scale (mRS) and the clinical outcome was assessed. A total of 14 patients (9 female patients, 5 male patients), with ages ranging from 17 to 57 years, met the criteria of endovascular therapy. The clinical symptoms of 12 patients had improved after receiving endovascular therapy and only 2 patients suffered from intracranial hemorrhage following the procedure. Complete recanalization of venous sinus was exhibited in 10/14 (71.4%) patients in group A when compared with 1/15 (6.7%) patients in group B. mRS were improved in the 12-month follow-up in groups A and B when compared with that at admission. In the present study, patients with acute CVST treated with stent retriever thrombectomy combined with local thrombolytic therapy had a favorable outcome. To conclude, the present study provides a treatment option in treating CVST, particularly for patients that present with evident cortical venous outflow stasis or deteriorate neurology, despite appropriate anticoagulant therapy.

5.
Brain Res Bull ; 134: 273-282, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28842304

ABSTRACT

OBJECTIVE: Temporal lobe epilepsy (TLE) is a common type of acquired epilepsy refractory to medical treatment. As such, establishing animal models of this disease is critical to developing new and effective treatment modalities. Because of their small head size, rodents are not suitable for comprehensive electroencephalography (EEG) evaluation via scalp or subdural electrodes. Therefore, a larger primate model that closely recapitulates signs of TLE is needed; here we describe a rhesus monkey model resembling chronic TLE. METHODS: Eight monkeys were divided into two groups: kainic acid (KA) group (n=6) and saline control group (n=2). Intra-amygdala KA injections were performed biweekly via an Ommaya device until obvious epileptiform discharges were recorded. Video-EEG recording was conducted intermittently throughout the experiment using both scalp and subdural electrodes. Brains were then analyzed for Nissl and glial fibrillary acid protein (GFAP) immunostaining. RESULTS: After 2-4 injections of KA (approximately 1.2-2.4mg, 0.12-0.24mg/kg), interictal epileptiform discharges (IEDs) were recorded in all KA-treated animals. Spontaneous recurrent seizures (SRSs) accompanied by symptoms mimicking temporal lobe absence (undetectable without EEG recording), but few mild motor signs, were recorded in 66.7% (four of six) KA-treated animals. Both IEDs and seizures indicated a primary epileptic zone in the right temporal region and contralateral discharges were later detected. Segmental pyramidal cell loss and gliosis were detected in the brain of a KA-treated monkey. CONCLUSIONS: Through a modified protocol of unilateral repetitive intra-amygdala KA injections, a rhesus monkey model with similar behavioral and brain electrical features as TLE was developed.


Subject(s)
Disease Models, Animal , Epilepsy, Temporal Lobe , Infusion Pumps, Implantable , Kainic Acid , Macaca mulatta , Amygdala/diagnostic imaging , Animals , Chronic Disease , Electrodes, Implanted , Electroencephalography , Epilepsy, Temporal Lobe/pathology , Epilepsy, Temporal Lobe/physiopathology , Functional Laterality , Gliosis/pathology , Gliosis/physiopathology , Male , Neurosurgical Procedures , Pyramidal Cells/pathology , Seizures/pathology , Seizures/physiopathology , Temporal Lobe/diagnostic imaging , Temporal Lobe/pathology , Temporal Lobe/physiopathology
6.
Neurol Res ; 38(4): 333-41, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27125512

ABSTRACT

Recurrences of aneurysms remain the major drawback of detachable coils for the endovascular treatment of intracranial aneurysms. The aim of the present study is to develop new modified coils, coating the surface of platinum coils with silk fibroin (SF) consisting of stromal cell-derived factor-1α (SDF-1α), and evaluate its acceleration of organization of cavities and reduction of lumen size in a rat aneurysm model. The morphological characteristics of SDF-1α-coated coils were examined using scanning electron microscopy (SEM). Fifty experimental aneurysms were created and randomly divided into five groups: three groups were embolized with SDF-1α-coated coils (8 mm) and two of these groups need transplantation of mesenchymal stem cells (MSCs) or endothelial progenitor cells (EPCs); one group was embolized with bare coils (8 mm) and another group severed as control. After coil implantation for 14 or 28 days, the coils were harvested and histological analysis was performed. SEM photographs showed that SF/SDF-1α-coated coils have uniform size and a thin film compared with bare coils. In the group treated with SDF-1α-coated coils, tissue organization was accelerated and the proliferation of α-smooth muscle actin positive cells was promoted in the aneurysmal sac. Compared with unmodified coils, on day 28, tissue organization was significantly greater in the group treated with SDF-1α-coated coils and MSC or EPC transplantation. These results suggest that SDF-1α-coated coils with MSC or EPC transplantation may be beneficial in the aneurysm healing and endothelialization at the orifice of embolized aneurysm.


Subject(s)
Aneurysm/therapy , Chemokine CXCL12/therapeutic use , Coated Materials, Biocompatible/therapeutic use , Endothelial Progenitor Cells/transplantation , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells/physiology , Animals , Chemokine CXCL12/metabolism , Disease Models, Animal , Embolization, Therapeutic , Endothelial Progenitor Cells/ultrastructure , Humans , Mesenchymal Stem Cells/ultrastructure , Microscopy, Electron, Scanning , Rats , Rats, Sprague-Dawley , Time Factors
7.
J Asian Nat Prod Res ; 14(9): 873-6, 2012.
Article in English | MEDLINE | ID: mdl-22924555

ABSTRACT

Epiberberine, a natural bioactive protoberberine alkaloid, was totally synthesized in short, convenient and low-cost, four-step reactions including cyclization, condensation, reduction, and ring-closing, with an overall yield of 26.1%.


Subject(s)
Berberine Alkaloids/chemical synthesis , Berberine/analogs & derivatives , Berberine/chemical synthesis , Berberine/chemistry , Berberine Alkaloids/chemistry , Catalysis , Cyclization , Molecular Structure
8.
Zhongguo Zhong Yao Za Zhi ; 37(2): 235-7, 2012 Jan.
Article in Chinese | MEDLINE | ID: mdl-22737858

ABSTRACT

OBJECTIVE: To investigate the chemical constituents of Corydalis yanhusuo. METHOD: The compounds were isolated and purified by column chromatography over macroporous absorption resin, silica gel, and Sephadex LH-20. Their structures were elucidated on the basis of physicochemical properties and spectral data. RESULT: 22 compounds were isolated and identified as corydaline (1), tetrahydropalmatine (2), protopine (3), tetrahydrocorysamine (4), tetrahydrocoptisine (5) , tetrahydroberberine (6), tetrahydrocolumbamine (7), noroxyhydrastine (8), dehydrocorydaline (9), glaucine (10), columbamine (11), 8-oxocoptisine (12), 13-methyl-columbamine (13), coptisine (14), palmatine (15), herberine (16), oxoglaucine (17), 13-methyl-palmatrubine (18), dehydrocorybulbine (19), stepharanine (20), adenosine (21), and N5 -acetylornithine (22). CONCLUSION: Compounds 13, 20, 21, and 22 were isolated from this plant for the first time.


Subject(s)
Corydalis/chemistry , Plant Extracts/analysis , Plant Extracts/isolation & purification , Adenosine/analysis , Adenosine/isolation & purification , Alkaloids/analysis , Alkaloids/isolation & purification , Apomorphine/analogs & derivatives , Apomorphine/analysis , Apomorphine/isolation & purification , Aporphines/analysis , Aporphines/isolation & purification , Berberine/analysis , Berberine/isolation & purification , Berberine Alkaloids/analysis , Berberine Alkaloids/isolation & purification , Chromatography, Liquid/methods , Spectrometry, Mass, Electrospray Ionization/methods
9.
J Sep Sci ; 34(22): 3200-7, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22012680

ABSTRACT

Epimedin C is one of the major bioactive constituents of Herba Epimedii. The aim of this study is to characterize and elucidate the structure of metabolites in the rat after administration of epimedin C. Metabolite identification was performed using a predictive multiple reaction monitoring-information dependent acquisition-enhanced product ion (pMRM-IDA-EPI) scan in positive ion mode on a hybrid triple quadrupole-linear ion trap mass spectrometer. A total of 18 metabolites were characterized by the changes in their protonated molecular masses, their MS/MS spectrum and their retention times compared with those of the parent drug. The results reveal possible metabolite profiles of epimedin C in rats; the metabolic pathways including hydrolysis, hydroxylation, dehydrogenation, demethylation and conjugation with glucuronic acid and different sugars were observed. This study provides a practical approach for rapidly identifying complicated metabolites, a methodology that could be widely applied for the structural characterization of metabolites of other compounds.


Subject(s)
Chromatography, High Pressure Liquid/methods , Drugs, Chinese Herbal/chemistry , Flavonoids/chemistry , Flavonoids/metabolism , Plant Extracts/chemistry , Plant Extracts/metabolism , Animals , Flavonoids/administration & dosage , Male , Mass Spectrometry/methods , Plant Extracts/administration & dosage , Rats , Rats, Sprague-Dawley
10.
Zhongguo Zhong Yao Za Zhi ; 36(8): 1024-7, 2011 Apr.
Article in Chinese | MEDLINE | ID: mdl-21809577

ABSTRACT

OBJECTIVE: To investigate the chemical constituents of the branches and leaves of Polyalthia nemoralis. METHOD: The compounds were isolated and purified by silica gel, macroporous adsorption resin and Sephadex LH-20 column chromatographic methods. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data. RESULT: Fourteen compounds were isolated and identified as syringic acid (1), 3-methoxy-4-hydroxycinnamic acid (2), vanillic acid (3), 4-hydroxybenzoic acid (4), mauritianin (5), (+)-xylopinidine (6), (+)-oblongine(7), (+)-tembetarine (8), eythritol (9), D-mannitol (10), ethyl-beta-D-glucopyranoside (11), (+)-magnoflorine (12), stepharanine (13), (2S, 4R)-4-hydroxy-2-piperidine-carboxylic acid (14), respectively. CONCLUSION: All the compounds were isolated from the genus Polyalthia for the first time; compounds 6 and 13 showed inhibitation activities against multi tumor cell lines.


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Plant Stems/chemistry , Polyalthia/chemistry , Alkaloids/chemistry , Alkaloids/isolation & purification , Alkaloids/pharmacology , Aporphines/chemistry , Aporphines/isolation & purification , Aporphines/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Chromatography, Agarose/methods , Coumaric Acids/chemistry , Coumaric Acids/isolation & purification , Coumaric Acids/pharmacology , Gallic Acid/analogs & derivatives , Gallic Acid/chemistry , Gallic Acid/isolation & purification , Gallic Acid/pharmacology , Humans , Kaempferols/chemistry , Kaempferols/isolation & purification , Kaempferols/pharmacology , Parabens/chemistry , Parabens/isolation & purification , Parabens/pharmacology , Plant Extracts/isolation & purification , Vanillic Acid/chemistry , Vanillic Acid/isolation & purification , Vanillic Acid/pharmacology
11.
Zhongguo Zhong Yao Za Zhi ; 35(1): 53-7, 2010 Jan.
Article in Chinese | MEDLINE | ID: mdl-20349716

ABSTRACT

OBJECTIVE: To investigate the active constituents of the branches and leaves of Polyalthia nemoralis. METHOD: The compounds were isolated and purified by silica gel, macroporous adsorption resin and Sephadex LH-20 column chromatographic methods. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data. RESULT: Eight compounds were isolated and identified as: zincpolyanemin (1), nickel bis-(pyridine-N-oxide-2-thiolate) (2), cupric bis (pyridine-N-oxide-2-thiolate (3), 2-methanesulfonyl-pyridine (4), 2-pyridinethiolate N-oxide (5), 2,2'-dithiodipyridine (6), 2-thiohydroxypyridin-N-oxide-2-S-beta-D-gluco pyranoside (7) and pyridine-N-oxide (8), respectively. CONCLUSION: Compounds 2, 4-6, 8 were new natural products. The bioassays in vitro against five human tumor cell lines with MTT method showed stronger cytotoxic activities (IC50 0.05-0.09 mg x L(-1)) for compounds 1-3 and 6, and weaker cytotoxic activities (IC50 5.49-7.71 mg x L(-1)) for compound 5.


Subject(s)
Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/pharmacology , Plant Leaves/chemistry , Plant Stems/chemistry , Polyalthia/chemistry , Pyridines/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Humans , Magnetic Resonance Spectroscopy
12.
Zhongguo Zhong Yao Za Zhi ; 34(18): 2343-5, 2009 Sep.
Article in Chinese | MEDLINE | ID: mdl-20030084

ABSTRACT

OBJECTIVE: To investigate the aporphine alkaloids in the branches and leaves of Polyalthia nemoralis. METHOD: The compounds were isolated and purified by silica gel and Sephadex LH-20 column chromatographies. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data. RESULT: Five aporphine alkaloids were isolated and identified as: bidebiline A (1), annobraine (2), lanuginosine (3), liriodenine (4), oxostephanosine (5), respectively. CONCLUSION: For the first time, Compounds 2 and 5 were obtained from Polyalthia while 1, 3 and 4 isolated from this plant. The bioassays in vitro against five human tumor cell lines with MTT method showed moderate cytotoxic activities (IC50 1 mg x L(-1)) of compounds 3-5.


Subject(s)
Aporphines/chemistry , Polyalthia/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Aporphines/isolation & purification , Aporphines/pharmacology , Cell Line, Tumor , Humans , Plant Leaves/chemistry , Plant Stems/chemistry
13.
J Asian Nat Prod Res ; 10(7-8): 663-71, 2008.
Article in English | MEDLINE | ID: mdl-18636379

ABSTRACT

Four new alkaloids, polynemoralines A (1), B (2), C (3), and D (4), were isolated from the branches and leaves of Polyalthia nemoralis A DC. The structures of 1-4 were elucidated mainly on the basis of spectroscopic methods. The structure of 4 was confirmed by X-ray diffraction analysis.


Subject(s)
Alkaloids/chemistry , Polyalthia/chemistry , Models, Molecular , Molecular Structure
14.
Chem Pharm Bull (Tokyo) ; 53(12): 1610-2, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16327202

ABSTRACT

Three new podocarpane-type diterpenoids, 3beta,12-dihydroxy-13-methyl-6,8,11,13-podocarpatetraen (1), 3beta,12-dihydroxy-13-methyl-5,8,11,13-podocarpatetraen-7-one (2), and 1-(7-hydroxy-2,6-dimethyl-1-naphthyl)-4-methyl-3-pentanone (3) (20(10-->5)-abeo-4,5-seco-5(10),6,8,11,13-podocarpapentaen-3-one) were isolated from callus of Securinega suffruticosa. The structures were elucidated by spectroscopic methods. Compounds 1, 2, and 3 showed cytotoxic activity against five human cancer cell lines (A549, BEL 7402, BGC-823, HCT-8, A2780).


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Diterpenes/chemistry , Euphorbiaceae/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Carbohydrate Conformation , Cell Line, Tumor , Diterpenes/isolation & purification , Diterpenes/pharmacology , Drug Screening Assays, Antitumor , Humans , Magnetic Resonance Spectroscopy , Spectrometry, Mass, Electrospray Ionization , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Tetrazolium Salts , Thiazoles
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