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1.
Mol Cell Biochem ; 476(1): 269-277, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32918705

RESUMO

Liver sinusoidal endothelial cells (LSECs) play a key role in the initiation and neoangiogenesis of liver regeneration. We presume that the abnormity of the VEGF/VEGFR2 and its pathway gene Id1, Wnt2 and HGF expression in aged LSECs may be an important mechanism to affect liver regeneration of the elderly. LSECs from two different groups (adult and old) were isolated in a rodent model, and observed by SEM and TEM. The adult and old rats were underwent 70% partial hepatectomy. The proliferation of hepatocytes and LSECs were analyzed by Immunofluorescence staining. The expression of VEGF/VEGFR2 and its pathway gene in isolated LSECs and liver tissue after hepatectomy were detected by qRT-PCR and Western blot. There is a decreased number of endothelial fenestrae in the LSECs of the old group, compared to the adult group. The old group had a lower expression of VEGF/VEGFR2 and its pathway gene than the adult groups (p < 0.01). The results of western blot were consistent with those of qRT-PCR. The hepatocytes had a high proliferation rate at first 4 days after hepatectomy, and a significantly higher proliferation rate in the adult group. The LSECs began to proliferate after 4 days of hepatectomy, and showed a quantity advantage in the adult group. The adult group had a significantly higher expression of VEGF/VEGFR2 and its pathway gene after hepatectomy than the old group (p < 0.01). LSCEs turn to be defenestration in structure and have a low expression of VEGF/VEGFR2 and its pathway gene with aging.


Assuntos
Envelhecimento , Capilares/metabolismo , Células Endoteliais/metabolismo , Fígado/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Proliferação de Células , Hepatectomia , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Proteína 1 Inibidora de Diferenciação/metabolismo , Fígado/irrigação sanguínea , Regeneração Hepática , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Fenótipo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Wnt/metabolismo
2.
Nat Prod Res ; 33(11): 1612-1616, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29368956

RESUMO

Three new compounds (1-3) and seven known compounds (4-10) have been isolated from the ethanolic extract of Viburnum macrocephalum f. keteleeri using bioactivity-guided fractionation and identified as methyl (2-α-L-rhamnopyranosyloxy)acetate (1), methyl (2R-3-α-L-rhamnopyranosyloxy)glycerate (2), methyl (3R-4-α-L-rhamnopyranosyloxy-3-hydroxy)butanoate (3), bridelionoside B (4), (6S,7E,9R)-roseoside (5), linarionoside A (6), 3,7,11-trimethyl-1,6-dodecadien-3,10,11-triol (7), (+)-8-hydroxylinalool (8), ß-sitosterol (9) and daucosterol (10). The structures of 1-3, including absolute configurations, were determined by spectroscopic data (1H and 13C NMR, HSQC, HMBC and ORD) and chemical methods. In addition, compounds 1-8 were assayed for their insecticidal and antimicrobial activities. Compounds 7 and 8 exhibited moderately insecticidal effects against Mythimna separata with LD50 values of 180 and 230 µg g-1, respectively. Compounds 2, 3, 7 and 8 showed varying antimicrobial activities with IC50 values ranging from 125 to 529 µM.


Assuntos
Anti-Infecciosos/farmacologia , Inseticidas/farmacologia , Viburnum/química , Animais , Anti-Infecciosos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Inseticidas/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mariposas/efeitos dos fármacos , Extratos Vegetais/química , Sitosteroides/análise
3.
Nat Prod Res ; 33(18): 2662-2667, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29703100

RESUMO

The ethanolic extract of the stems of Viburnum fordiae Hance showed insecticidal and α-glucosidase inhibitory activities and then was fractionated by bioactivity-guided fractionation to obtain a rare C13-norisoprenoid (1), together with a new phenolic glycoside (2), and seven known compounds, alangionoside C (3), pisumionoside (4), koaburaside (5), 3,5-dimethoxy-benzyl alcohol 4-O-ß-d-glucopyranoside (6), 3,4,5-trimethoxybenzyl-ß-d-glucopyranoside (7), arbutin (8), and salidroside (9). The previously undescribed compounds were elucidated as (3R,9R)-3-hydroxy-7,8-didehydro-ß-ionyl 9-O-α-d-arabinopyranosyl-(1→6)-ß-d-glucopyranoside (1) and 2-(4-O-ß-d-glucopyranosyl)syringylpropane-1,3-diol (2) by spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, HSQC-TOCSY, HRESIMS, IR and ORD) and chemical methods. Compound 1 showed potent insecticidal effect against Mythimna separata with LD50 value of 140 µg g-1. Compounds 2, 5, 6, 8 and 9 showed varying α-glucosidase inhibitory activity with IC50 values ranging from 148.2 to 230.9 µM.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inseticidas/química , Inseticidas/farmacologia , Viburnum/química , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Glucosídeos/química , Glucosídeos/farmacologia , Glicosídeos/química , Glicosídeos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Mariposas/efeitos dos fármacos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
4.
Oxid Med Cell Longev ; 2018: 6069150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581534

RESUMO

The aim of this study was to investigate whether uric acid (UA) might exert neuroprotection via activating the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and regulating neurotrophic factors in the cerebral cortices after transient focal cerebral ischemia/reperfusion (FCI/R) in rats. UA was intravenously injected through the tail vein (16 mg/kg) 30 min after the onset of reperfusion in rats subjected to middle cerebral artery occlusion for 2 h. Neurological deficit score was performed to analyze neurological function at 24 h after reperfusion. Terminal deoxynucleotidyl transferase-mediated dNTP nick end labeling (TUNEL) staining and hematoxylin and eosin (HE) staining were used to detect histological injury of the cerebral cortex. Malondialdehyde (MDA), the carbonyl groups, and 8-hydroxyl-2'-deoxyguanosine (8-OHdG) levels were employed to evaluate oxidative stress. Nrf2 and its downstream antioxidant protein, heme oxygenase- (HO-) 1,were detected by western blot. Nrf2 DNA-binding activity was observed using an ELISA-based measurement. Expressions of BDNF and NGF were analyzed by immunohistochemistry. Our results showed that UA treatment significantly suppressed FCI/R-induced oxidative stress, accompanied by attenuating neuronal damage, which subsequently decreased the infarct volume and neurological deficit. Further, the treatment of UA activated Nrf2 signaling pathway and upregulated BDNF and NGF expression levels. Interestingly, the aforementioned effects of UA were markedly inhibited by administration of brusatol, an inhibitor of Nrf2. Taken together, the antioxidant and neuroprotective effects afforded by UA treatment involved the modulation of Nrf2-mediated oxidative stress and regulation of BDNF and NGF expression levels. Thus, UA treatment could be of interest to prevent FCI/R injury.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Úrico/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Animais , Western Blotting , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Ensaio de Imunoadsorção Enzimática , Heme Oxigenase-1/metabolismo , Imunoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
5.
Sleep Med ; 20: 110-5, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-27318234

RESUMO

OBJECTIVE: Rapid eye movement (REM) sleep behavior disorder (RBD) and sleep-disordered breathing (SDB) are two major sleep disturbances observed in patients with Parkinson's disease (PD). However, prior studies exploring the clinical correlations between RBD and SDB in PD have been limited. We aimed to investigate the relationship between RBD and SDB in PD using a case-control study. METHODS: A total of 46 PD patients with Hoehn-Yahr stages ranging from 1 to 3 participated in the present study. Participants underwent polysomnography to diagnose the presence of RBD and SDB, and were classified into groups, accordingly. SDB was defined as an apnea-hypopnea index greater than 5. Comparison of clinical and sleep-respiratory parameters was performed among them. RESULTS: SDB was more frequent in the RBD group than in the non-RBD group (51.4% vs 9.1%, p = 0.016). PD patients with RBD had significantly reduced mean SaO2 and more severe sleep apnea-related parameters during total sleep and non-REM sleep in comparison with non-RBD PD patients. However, there were no differences on the REM-related apnea/hypopnea variables between participants with and without RBD (p > 0.05). Both the frequency of RBD and RBD screening questionnaire (RBDSQ) scores were higher in the participants with SDB than in the participants without SDB (p <0.05). Furthermore, a significant negative correlation was found between RBDSQ and mean SaO2 in all participants. CONCLUSIONS: In PD patients, SDB is more frequent and more severe in patients with RBD than in patients without, and RBD increases the risk of hypoxemia during sleep.


Assuntos
Doença de Parkinson/complicações , Transtorno do Comportamento do Sono REM/diagnóstico , Síndromes da Apneia do Sono/diagnóstico , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Transtorno do Comportamento do Sono REM/complicações , Índice de Gravidade de Doença , Inquéritos e Questionários
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1169-72, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26415421

RESUMO

Colloidal PbSe QDs were prepared with the particle size of 3. 6, 5. 1 and 6. 0 nm, and the temperature-dependent optical properties of colloidal PbSe QDs were investigated. At the room temperature, the experiment showed that there is red shift with increasing temperature; photoluminescence spectra of large size colloidal PbSe QDs is blue shifted with increasing temperature. Proposed a temperature detection method of integrated circuit was proposed based on photoluminescence spectra of colloidal PbSe QDs. The method for temperature detection includes colloidal PbSe quantum dots deposited on the surface of the printed circuit board, colloidal PbSe quantum dots of the surface are excited by the laser and infrared spectrometer receives photoluminescence spectra. Image acquisition system used for micron scale areas of temperature detection collects a tiny and specific areas imaging in the surface of chip. Experiments showed that the measurement accuracy is ±3 °C and the relative error is less than 5%.

9.
Chin Med J (Engl) ; 128(15): 2040-4, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26228215

RESUMO

BACKGROUND: Magnetic anchored surgical instruments (MASI), relying on magnetic force, can break through the limitations of the single port approach in dexterity. Individual characteristic abdominal wall thickness (ICAWT) deeply influences magnetic force that determines the safety of MASI. The purpose of this study was to research the abdominal wall characteristics in MASI applied environment to find ICAWT, and then construct an artful method to predict ICAWT, resulting in better safety and feasibility for MASI. METHODS: For MASI, ICAWT is referred to the thickness of thickest point in the applied environment. We determined ICAWT through finding the thickest point in computed tomography scans. We also investigated the traits of abdominal wall thickness to discover the factor that can be used to predict ICAWT. RESULTS: Abdominal wall at C point in the middle third lumbar vertebra plane (L3) is the thickest during chosen points. Fat layer thickness plays a more important role in abdominal wall thickness than muscle layer thickness. "BMI-ICAWT" curve was obtained based on abdominal wall thickness of C point in L3 plane, and the expression was as follow: f(x) = P1 × x 2 + P2 × x + P3, where P1 = 0.03916 (0.01776, 0.06056), P2 = 1.098 (0.03197, 2.164), P3 = -18.52 (-31.64, -5.412), R-square: 0.99. CONCLUSIONS: Abdominal wall thickness of C point at L3 could be regarded as ICAWT. BMI could be a reliable predictor of ICAWT. In the light of "BMI-ICAWT" curve, we may conveniently predict ICAWT by BMI, resulting a better safety and feasibility for MASI.


Assuntos
Parede Abdominal/anatomia & histologia , Instrumentos Cirúrgicos , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Tomografia Computadorizada por Raios X
10.
Biomed Mater ; 10(4): 045023, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26290516

RESUMO

Using a decellularized liver matrix (DLM) to reengineer liver tissue is a promising therapy for end-stage liver disease. However, the limited supply of donor organs still hampers its potential clinical application, while a xenogenic decellularized matrix may bring a risk of zoonosis and immunological rejection. Therefore, an appropriate alternative scaffold is needed. In this research, we established a decellularized splenic matrix (DSM) in a rodent model, which preserved the 3D ultrastructure, the components of the extracellular matrix (ECM) and the native vascular network. The DSM and DLM had similar components of ECM, and similar mechanical properties. Hepatocytes were seeded to the DSM and DLM for dynamic culturing up to 6 d, and distributed both in decellularized sinusoidal spaces and around the vessels. The TUNEL-positive cell percentage in a dynamic culturing decellularized splenic matrix (dDSM) was 10.7% ± 3.6% at 3d and 25.8% ± 5.6% at 5d, although 14.2% ± 4.5% and 24.8% ± 2.9%, respectively, in a dynamic culturing decellularized liver matrix (dDLM) at the same time point (p > 0.05). Primary hepatocytes in the dDSM and dDLM expressed albumin, G6pc and Ugt1a1. The gene expression of Cyp2b1, Cyp1a2 and HNF1α in the gene transcription level revealed hepatocytes had lower gene expression levels in the dDSM compared with the dDLM at 3d, but better than those in a sandwich culture. The cumulative albumin production at 6 d of culture was 80.7 ± 9.6 µg per million cells in the dDSM and 89.6 ± 4.6 µg per million cells in the dDLM (p > 0.05). In summary, the DSM is a promising 3D scaffold for hepatocyte cultivation in vitro.


Assuntos
Matriz Extracelular/química , Hepatócitos/citologia , Hepatócitos/transplante , Fígado Artificial , Baço/química , Alicerces Teciduais , Animais , Sistema Livre de Células , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Hepatócitos/fisiologia , Masculino , Teste de Materiais , Projetos Piloto , Impressão Tridimensional , Ratos , Ratos Sprague-Dawley
11.
World J Gastroenterol ; 21(26): 8073-80, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26185378

RESUMO

AIM: To explore the anatomical feasibility of portacaval shunt using a magnetic compression technique (MCT) in cadavers. METHODS: Computed tomography (CT) images of 30 portal hypertensive patients were obtained. The diameters of the portal vein (PV), the inferior vena cava (IVC), and distance between the two structures were measured. Similar measurements were performed on 20 adult corpses. The feasibility of portacaval shunt based on those measurements was analyzed. First stage of the extrahepatic portacaval shunt using MCT was performed on five cadavers. Specifically, the PV and IVC were exposed through an abdominal incision of the cadavers. The parent magnet was introduced from the femoral vein and was delivered into the IVC by an anchor wire and a 5F Cook catheter. The daughter magnet was introduced into the PV through the splenic vein using an interventional guide wire. When the daughter magnet met the parent magnet, they automatically clipped together and the first stage of the portacaval shunt was set up. RESULTS: The average diameters of the PV and the IVC measured from the 30 CT image were 14.39 ± 2.36 mm and 18.59 ± 4.97 mm, respectively, and the maximum and minimum distances between the PV and the IVC were 9.79 ± 4.56 mm and 9.50 ± 4.79 mm, respectively. From 20 cadavers, the average diameters of the PV and the IVC were 14.48 ± 1.47 mm and 24.71 ± 2.64 mm, and the maximum and minimum distances between the PV and the IVC were 10.14 ± 1.70 mm and 8.93 ± 1.17 mm, respectively. The distances between the PV and the IVC from both the CT images and the cadavers were within the effective length of portacaval anastomosis using MCT (30.30 ± 4.19 mm). The PV and IVC are in close proximity to each other with no intervening tissues or structures in between. Simulated surgeries of the first stage using MCT on five cadavers was successfully performed. CONCLUSION: Anatomically, extrahepatic portacaval shunt employing MCT is highly feasible in humans.


Assuntos
Hipertensão Portal/cirurgia , Magnetismo , Derivação Portocava Cirúrgica/métodos , Veia Porta/cirurgia , Veia Cava Inferior/cirurgia , Adulto , Idoso , Cadáver , Constrição , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Hipertensão Portal/diagnóstico por imagem , Magnetismo/instrumentação , Imãs , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Flebografia/métodos , Derivação Portocava Cirúrgica/instrumentação , Veia Porta/diagnóstico por imagem , Veia Cava Inferior/diagnóstico por imagem
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(1): 20-2, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24783525

RESUMO

ZnCuInS/ZnSe/ZnS quantum dots were non-toxic and heavy-metal free semiconductor nanocrystals. In the present paper, ZnCuInS/ZnSe/ZnS core/shell/shell quantum dots were prepared with the particle size of 3.3, 2.7 and 2.3 nm. The photoluminescence of ZnCuInS/ZnSe/ZnS quantum dots with different size were measured, and the wavelength of peak was blue-shifted with decreasing the diameter. The wavelength of absorption peaks and photoluminescence peaks were 510 nm, 611 nm (3.3 nm), 483 nm, 583 nm (2.7 nm) and 447 nm and 545 nm(2.3 nm). The obvious size-dependence of ZnCuInS/ZnSe/ZnS quantum dots was shown. The Stokes shifts of ZnCuInS/ZnSe/ZnS quantum dots were 398 meV (3.3 nm), 436 meV (2.7 nm) and 498 meV (2.3 nm). Such large Stokes shifts indicate that the emission should be ascribed to the defect-related recombination. The temperature-dependent photoluminescence of ZnCuInS/ZnSe/ZnS quantum dots with the particle size of 3.3 nm were measured. The wavelength of peaks was red-shifted with increasing temperature and the intensity of photoluminescence spectra was decreased with increasing temperature. Therefore, the emission was concluded to be the transition from the conduction band to defect state.

13.
Neuropeptides ; 47(2): 93-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23375440

RESUMO

Oxytocin (OXT), a nonapeptide hormone of posterior pituitary, reaches the central nervous system from systemic blood circulation with a difficulty because of the blood-brain barrier (BBB). The interest has been expressed in the use of the nasal route for delivery of OXT to the brain directly, exploiting the olfactory pathway. Our previous study has demonstrated that OXT in the central nervous system rather than the blood circulation plays an important role in rat pain modulation. The communication tried to investigate the interaction between the OXT and pain modulation in Chinese patients with headache to understand the OXT effect on human pain modulation. The results showed that (1) intranasal OXT could relieve the human headache in a dose-dependent manner; (2) OXT concentration in both plasma and cerebrospinal fluid (CSF) increased significantly in headache patients in relation with the pain level; and (3) there was a positive relationship between plasma and CSF OXT concentration in headache patients. The data suggested that intranasal OXT, which was delivered to the central nervous system through olfactory region, could treat human headache and OXT might be a potential drug of headache relief by intranasal administration.


Assuntos
Cefaleia/tratamento farmacológico , Ocitocina/uso terapêutico , Dor/tratamento farmacológico , Administração Intranasal , Adulto , Povo Asiático , Relação Dose-Resposta a Droga , Feminino , Cefaleia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Ocitocina/sangue , Ocitocina/líquido cefalorraquidiano , Dor/fisiopatologia , Medição da Dor/efeitos dos fármacos , Adulto Jovem
14.
Neurol Sci ; 34(8): 1355-65, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23187788

RESUMO

Cholesterol plays an important role in synaptic plasticity, learning and memory. To better explore how dietary cholesterol contributes to learning and memory and the related changes in synaptic structural plasticity, rats were categorized into a regular diet (RD) group and a cholesterol-enriched diet (CD) group, and were fed with respective diet for 2 months. Dietary cholesterol impacts on learning and memory, hippocampal synaptic ultrastructure, expression levels of postsynaptic density-95 (PSD-95), synaptophysin (SYP) and cannabinoid receptor type 1 (CB1R) were investigated. We found CD rats had better performances in learning and memory using Morris water maze and object recognition test than RD rats. The memory improvement was accompanied with alterations of synaptic ultrastructure in the CA1 area of the hippocampus evaluated by electron microscopy, enhanced immunoreactivity of SYP, a presynaptic marker in hippocampus detected by immunocytochemistry, as well as increased levels of PSD-95, SYP and decreased level of CB1R in brains of CD rats determined by Western blot. Taken together, the results suggest that the improvement of learning and memory abilities of the young adult rats induced by dietary cholesterol may be linked with changes in synaptic structural plasticity in the brain.


Assuntos
Colesterol na Dieta/farmacologia , Hipocampo/efeitos dos fármacos , Memória/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Animais , Colesterol na Dieta/análise , Colesterol na Dieta/sangue , Hipocampo/ultraestrutura , Masculino , Ratos , Ratos Wistar , Sinapses/ultraestrutura
15.
J Zhejiang Univ Sci B ; 13(10): 763-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23024043

RESUMO

To our knowledge, few reports on Demodex studied at the molecular level are available at present. In this study our group, for the first time, cloned, sequenced and analyzed the chitin synthase (CHS) gene fragments of Demodex folliculorum, Demodex brevis, and Demodex canis (three isolates from each species) from Xi'an China, by designing specific primers based on the only partial sequence of the CHS gene of D. canis from Japan, retrieved from GenBank. Results show that amplification was successful only in three D. canis isolates and one D. brevis isolate out of the nine Demodex isolates. The obtained fragments were sequenced to be 339 bp for D. canis and 338 bp for D. brevis. The CHS gene sequence similarities between the three Xi'an D. canis isolates and one Japanese D. canis isolate ranged from 99.7% to 100.0%, and those between four D. canis isolates and one D. brevis isolate were 99.1%-99.4%. Phylogenetic trees based on maximum parsimony (MP) and maximum likelihood (ML) methods shared the same clusters, according with the traditional classification. Two open reading frames (ORFs) were identified in each CHS gene sequenced, and their corresponding amino acid sequences were located at the catalytic domain. The relatively conserved sequences could be deduced to be a CHS class A gene, which is associated with chitin synthesis in the integument of Demodex mites.


Assuntos
Quitina Sintase/genética , Ácaros/enzimologia , Ácaros/genética , Animais , Sequência de Bases , Clonagem Molecular , Primers do DNA/genética , Ácaros/classificação , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(7): 1943-5, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23016359

RESUMO

In the present paper ZnCuInS/ZnS core/shell quantum dots were prepared with the particle size of 3.2 nm. Its radiation is based on the donoracceptor pair transitions, not the band edge emission. According to the measurement of photoluminescence spectrum emitted by ZnCuInS/ZnS core/shell quantum dots, the emitting peak of 620 nm and the full width at half-maximum of 95 nm were achieved as red emitter; meanwhile, organic poly(N, N'-bis(4-butylphenyl)-N, N'-bis(phenyl) benzidine) (Poly-TPD) film was deposited and used as cyan-emitter with the peak of 480 nm. Two structures of Poly-TPD were analyzed and discussed according to the photoluminescence spectrum. Two wavelengths are complementary color. Therefore, two films were deposited one by one as bilayer emitter to obtain the complementary emission. After the suitable bias was applied on the films, the white emission was achieved with the Commission Internationale de l' Eclairage (CIE) chromaticity coordinates of (0.336, 0.339) and color rendering index of 92. Therefore, the bilayer-structure is a promising candidate for white light emitting diodes fabrication.

17.
Parasitol Res ; 111(5): 2109-14, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22903416

RESUMO

Due to the difficulty of DNA extraction for Demodex, few studies dealt with the identification and the phyletic evolution of Demodex at molecular level. In this study, we amplified, sequenced, and analyzed a complete (Demodex folliculorum) and an almost complete (D12 missing) (Demodex brevis) ribosomal DNA (rDNA) sequence and also analyzed the primary sequences of divergent domains in small-subunit ribosomal RNA (rRNA) of 51 species and in large-subunit rRNA of 43 species from four superfamilies in Acari (Cheyletoidea, Tetranychoidea, Analgoidea, and Ixodoidea). The results revealed that 18S rDNA sequence was relatively conserved in rDNA-coding regions and was not evolving as rapidly as 28S rDNA sequence. The evolutionary rates of transcribed spacer regions were much higher than those of the coding regions. The maximum parsimony trees of 18S and 28S rDNA appeared to be almost identical, consistent with their morphological classification. Based on the fact that the resolution capability of sequence length and the divergence of the 13 segments (D1-D6, D7a, D7b, and D8-D12) of 28S rDNA were stronger than that of the nine variable regions (V1-V9) of 18S rDNA, we were able to identify Demodex (Cheyletoidea) by the indels occurring in D2, D6, and D8.


Assuntos
Ácaros e Carrapatos/classificação , Ácaros e Carrapatos/genética , DNA Espaçador Ribossômico/genética , DNA Ribossômico/genética , Filogenia , Análise de Sequência de DNA , Animais , Análise por Conglomerados , Sequência Conservada , DNA Ribossômico/química , DNA Espaçador Ribossômico/química , Variação Genética , Mutação INDEL
18.
Dalton Trans ; 40(19): 5302-6, 2011 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-21465045

RESUMO

Reactions of the precursors [Ni(macrocyclic ligand)](2+) with [W(CN)(8)](3-) afford two octacyanotungstate-based assemblies, (H(2)L(1))(0.5)[Ni(L(1))][W(CN)(8)]·2DMF·H(2)O (L(1) = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) (1) and [Ni(L(2))](3)[W(CN)(8)](2)·4H(2)O (L(2) = 3,10-dipropyl-1,3,5,8,10,12-hexaazacyclotetradecane) (2). Single crystal X-ray diffraction shows that 1 consists of anionic one-dimensional (1D) linear chains, while 2 is built of 2D graphite-like layers with (6, 3) topology. Magnetic studies reveal that both complexes exhibit metamagnetic behavior from the spin-canted antiferromagnet to the ferromagnet induced by field.

19.
Biochem Biophys Res Commun ; 407(3): 593-8, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21426903

RESUMO

In this paper, we determine the mutant W203F structure of TFsß-glucanase, which contains aromatic residue Trp203 at the active site of the enzyme. Residue Trp203 is stacked with the glucose product of cellotriose. Further analysis reveals that two extra calcium ions and a Tris molecule bind to the mutant structure. A Tris molecule, bound to the catalytic residues of Glu56 and Glu60, was found at the position normally taken by substrate binding at the -1 subsite. In addition, a second Ca(2+) ion was found near the residues Phe152 and Glu154 on the protein's surface, and a third one near the active site residue Asp202. Kinetic experiments reveal that both Tris and imidazole are competitive inhibitors, while calcium is a noncompetitive inhibitor for TFsß-glucanase. The two types of enzymatic inhibition are first-time descriptions for the glycosyl hydrolase family 16.


Assuntos
Cálcio/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Glicosídeo Hidrolases/química , Trometamina/farmacologia , Cálcio/química , Domínio Catalítico/genética , Cátions Bivalentes/química , Cátions Bivalentes/farmacologia , Cristalografia por Raios X , Fibrobacter/enzimologia , Glicosídeo Hidrolases/genética , Imidazóis/química , Imidazóis/farmacologia , Mutação , Paenibacillus/enzimologia , Trometamina/química , Triptofano/química , Triptofano/genética
20.
Antonie Van Leeuwenhoek ; 99(3): 663-70, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21188520

RESUMO

Two Gram-negative moderately halophilic bacterial strains, designated Ad-1(T) and C-12, were isolated from Aiding salt lake of Xinjiang in China. The novel isolates were subjected to a polyphasic taxonomic study. Cells of these strains were cocci or short rods and motile with polar flagella. Colonies produced brown-red pigment. The isolates grew in the range of 0.5-25% (w/v) NaCl, pH 5.5-10.5 and 4-45°C. Analysis of their 16S rRNA gene sequences indicated that strains Ad-1(T) and C-12 belonged to the genus Halomonas showing 92.7-98.4% similarity with the type species. The isoprenoid quinones of the isolates were Q-9 and Q-8. The major cellular fatty acids were C18:1ω7c, C16:1ω7c/6c, C16:0, C12:0-3OH and C10:0. The DNA G + C contents of strains Ad-1(T) and C-12 were 64.6 and 63.9 mol%, respectively. The DNA relatedness between the two isolates was 89.2%. The similarities of these newly isolated strains with closely related type strains were lower than 35% at the genetic level. Based on phenotypic, chemotaxonomic and genetic characteristics, the representative strain Ad-1(T) is considered to be a novel species of the genus Halomonas, for which the name Halomonas aidingensis sp. nov. is proposed, with Ad-1(T) (= CGMCC 1.10191(T) = NBRC 106173(T)) as the type strain.


Assuntos
Halomonas/genética , Composição de Bases/genética , China , Halomonas/classificação , Filogenia , RNA Ribossômico 16S/genética
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