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1.
ACS Omega ; 6(48): 33159-33170, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34901667

RESUMO

In this study, we used one-pot A2 + B3 polymerizations to synthesize two aliphatic + alicyclic polymer dots (PDs) having non-conjugated hyperbranched structures, employing two types of dianhydrides as the A2 components, possessing bridged bicyclic alkene (PD-BT) and non-alkene (PD-ET) units, and Jeffamine T403 polyetheramine (T403) as the B3 components. We prepared PD-ET from commercially available ethylenediaminetetraacetic dianhydride (EDTAD, A2) and T403 (B3) and PD-BT from bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA, A2) and T403 (B3). These two types of PDs possessed non-conjugated hyperbranched poly(amic acid) structures with terminal amino functional groups. PD-BT and PD-ET exhibited non-conventional fluorescence with emissions at 435 and 438 nm, respectively, and quantum yields of 12.8 and 14.0%, respectively. The fluorescence intensity of PD-ET was influenced by the pH, but PD-BT was less affected because of its rigid aliphatic bridged bicyclic structure. In aqueous solutions, the sizes of the PD-BT and PD-ET nanoparticles were 3-5 nm, and their net charges can be adjusted by varying the pH. These PDs were non-cytotoxic toward human MCF-7 breast cancer cells and human keratinocyte HaCaT cells at concentrations of 50 µg mL-1 for PD-BT and 500 µg mL-1 for PD-ET. Confocal microscopic bioimaging revealed that the PDs were located within the cells after treatment for 6 h. These PDs were easy to prepare, highly water-soluble, and possessed a large number of peripheral functional groups for further modification. Combined with their non-conventional fluorescence, they appear to have potential uses in bioimaging and as drug-labeling carriers.

2.
Anal Chem ; 93(46): 15517-15524, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34726908

RESUMO

Precisely detecting the catalysts' hot spots temperature in situ instantly during photocatalysis is a great challenge but extremely important for chemical reactions. However, no efficient method has been developed to instantly detect the hot spots temperature in situ during photocatalysis. Herein, we designed a simple and convenient method to measure the instant hot spots temperature in situ on the nanostructure surface during photocatalysis by operando Raman spectroscopy using 4-methoxyphenyl isocyanide (MI) as the probe molecule. The νN≡C frequency of MI varied linearly with temperature, which is caused by the orientation change of the MI induced by temperature, leading to the change in the frequency of the νN≡C bond that directly interacts with the nanostructure surface. Using in situ surface-enhanced Raman spectroscopy (SERS), the surface temperature of the catalysts illuminating for each time can be measured instantly. Interestingly, the catalytic activity of the hydrogen evolution reaction (HER) for the Au-Ag/Ag2S heterojunction nanorods (HJNRs) are higher than that for the Ag-Au-Ag HJNRs, although they have a lower surface temperature during photocatalysis; therefore, hot carriers and electronic structure contributed more to the catalytic activity of the Au-Ag/Ag2S HJNRs than that of the Ag-Au-Ag HJNRs. Such an instant hot spots temperature detecting method of catalysts can greatly facilitate the analysis of the mechanism of catalytic processes.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Ouro , Prata , Temperatura
3.
Nat Biotechnol ; 39(10): 1228-1238, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34183859

RESUMO

Temporary cardiac pacemakers used in periods of need during surgical recovery involve percutaneous leads and externalized hardware that carry risks of infection, constrain patient mobility and may damage the heart during lead removal. Here we report a leadless, battery-free, fully implantable cardiac pacemaker for postoperative control of cardiac rate and rhythm that undergoes complete dissolution and clearance by natural biological processes after a defined operating timeframe. We show that these devices provide effective pacing of hearts of various sizes in mouse, rat, rabbit, canine and human cardiac models, with tailored geometries and operation timescales, powered by wireless energy transfer. This approach overcomes key disadvantages of traditional temporary pacing devices and may serve as the basis for the next generation of postoperative temporary pacing technology.


Assuntos
Implantes Absorvíveis , Marca-Passo Artificial , Animais , Bloqueio Atrioventricular/terapia , Modelos Animais de Doenças , Cães , Desenho de Equipamento , Humanos , Camundongos , Coelhos , Ratos , Tecnologia sem Fio
4.
Nat Prod Res ; 35(13): 2137-2144, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31512485

RESUMO

One new xanthone, (±) garciesculenxanthone C (1), two new biphenyls, garciesculenbiphenyls A (2) and B (3), together with two known compounds, doitungbiphenyl B (4) and morusignin D (5), were isolated from Garcinia esculenta. The structures of new compounds were elucidated by spectroscopic analysis, and the absolute configuration of (±) garciesculenxanthone C (1) was assigned by a modified Mosher's method. All isolates were evaluated for their antistaphylococcal activities against Staphylococcus aureus Newman, USA300 LAC, USA400 MW2, and Mu50 strains. Among these, (±) garciesculenxanthone C (1) showed the best antistaphylococcal activity, and its effect was determined to be bactericidal by time-kill experiment.


Assuntos
Antibacterianos/farmacologia , Compostos de Bifenilo/isolamento & purificação , Compostos de Bifenilo/farmacologia , Garcinia/química , Prenilação , Staphylococcus aureus/efeitos dos fármacos , Xantonas/isolamento & purificação , Xantonas/farmacologia , Antibacterianos/química , Compostos de Bifenilo/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Testes de Sensibilidade Microbiana , Estereoisomerismo , Xantonas/química
5.
ACS Appl Mater Interfaces ; 13(1): 1152-1157, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33350805

RESUMO

Rapid detection of the handiness of chiral molecules is an important topic for pharmaceutical industries because chiral drugs with opposing handiness sometimes exhibit unwanted side effects. In this research, a rapid optical method is proposed to determine the handiness of the chiral drug "Thalidomide". The platform is a large array of three-dimensional (3D) twisted metamaterials fabricated with a novel method by combining nanospherical-lens lithography (NLL) and hole-mask lithography (HML). The fabrication is high-throughput and the twisted metamaterials cover a large area. Strong circular dichroism (CD) response is observed in the near-infrared (NIR) region, which enables the chiral detection to be performed by a low-cost and portable spectroscope system. The proposed nanofabrication method significantly improves the capabilities of NLL and HML, which can be quickly adapted to fabricate various periodic 3D metamaterials. In addition, the results of this research pave the road for the rapid penetration of nanophotonics into the pharmaceutical industries.


Assuntos
Nanoestruturas/química , Talidomida/química , Dicroísmo Circular/métodos , Estereoisomerismo
6.
Sci Adv ; 6(35): eabb1093, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32923633

RESUMO

Implantable drug release platforms that offer wirelessly programmable control over pharmacokinetics have potential in advanced treatment protocols for hormone imbalances, malignant cancers, diabetic conditions, and others. We present a system with this type of functionality in which the constituent materials undergo complete bioresorption to eliminate device load from the patient after completing the final stage of the release process. Here, bioresorbable polyanhydride reservoirs store drugs in defined reservoirs without leakage until wirelessly triggered valve structures open to allow release. These valves operate through an electrochemical mechanism of geometrically accelerated corrosion induced by passage of electrical current from a wireless, bioresorbable power-harvesting unit. Evaluations in cell cultures demonstrate the efficacy of this technology for the treatment of cancerous tissues by release of the drug doxorubicin. Complete in vivo studies of platforms with multiple, independently controlled release events in live-animal models illustrate capabilities for control of blood glucose levels by timed delivery of insulin.

7.
Pharmacol Res ; 147: 104328, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288080

RESUMO

A global transcriptional regulator, MgrA, was previously identified as a key determinant of virulence in Staphylococcus aureus. An 80% EtOH extract of Uncaria gambier was found to attenuate the virulence of S. aureus via its effects on MgrA. Using bioassay-guided fractionation, a polyphenolic polymer, uncariitannin, was found to be the main bioactive constituent of the extract, and its structure was characterized using spectral and chemical analysis. The molecular weight and polydispersity of uncariitannin were determined by gel permeation chromatography-refractive index-light scattering analysis. An electrophoretic mobility shift assay showed that uncariitannin could effectively inhibit the interaction of MgrA with DNA in a dose-dependent manner. Treatment with uncariitannin could decrease the mRNA and protein levels of Hla in both the S. aureus Newman and USA300 LAC strains. Further analysis of Hla expression levels in the Newman ΔmgrA and Newman ΔmgrA/pYJ335-mgrA strains indicated that uncariitannin altered Hla expression primarily in an MgrA-dependent manner. A mouse model of infection indicated that uncariitannin could attenuate MRSA virulence. In conclusion, uncariitannin may be a potential candidate for further development as an antivirulence agent for the treatment of S. aureus infection.


Assuntos
Antibacterianos , Polímeros , Polifenóis , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Uncaria , Virulência/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Feminino , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos Endogâmicos BALB C , Miocárdio/patologia , Polímeros/farmacologia , Polímeros/uso terapêutico , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Baço/efeitos dos fármacos , Baço/patologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade
8.
Food Chem Toxicol ; 125: 133-140, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597224

RESUMO

Fructus Psoraleae (FP) causes cholestatic liver injury; however, its main toxic constituents that are responsible for causing hepatotoxicity remained undetermined in previous studies. In the present study, psoralen and isopsoralen, the two main constituents of FP, were administered orally to rats (80 and 40 mg/kg, respectively) and mice (320 and 160 mg/kg, respectively) for 28 days, followed by biochemical and histopathological examinations to evaluate their hepatotoxicity. The results showed that psoralen and isopsoralen could induce the toxic reactions of liver and other organs in rats, while mice were not sensitive to these two compounds. Furthermore, the corresponding results indicated that administration of psoralen and isopsoralen repressed the expression of CYP7A1, BSEP, MRP2 and SULT2A1 and increased the expression of FXR and MRP3 in the rat liver. In summary, the toxic reactions of psoralen and isopsoralen are different in different species. In this study, multiple organ toxicity, such as cholestatic liver injury, occurs in rats, but not in mice. Psoralen and isopsoralen are the two main toxic constituents of FP. In addition, psoralen and isopsoralen cause liver injury, possibly through inhibiting bile acid excretion in the liver, leading to the accumulation of toxin in hepatocytes.


Assuntos
Colestase Intra-Hepática/induzido quimicamente , Ficusina/toxicidade , Furocumarinas/toxicidade , Hepatócitos/efeitos dos fármacos , Extratos Vegetais/química , Animais , Fabaceae , Feminino , Camundongos Endogâmicos ICR , RNA Mensageiro/metabolismo , Ratos Wistar
9.
Nat Med ; 24(12): 1830-1836, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30297910

RESUMO

Peripheral nerve injuries represent a significant problem in public health, constituting 2-5% of all trauma cases1. For severe nerve injuries, even advanced forms of clinical intervention often lead to incomplete and unsatisfactory motor and/or sensory function2. Numerous studies report the potential of pharmacological approaches (for example, growth factors, immunosuppressants) to accelerate and enhance nerve regeneration in rodent models3-10. Unfortunately, few have had a positive impact in clinical practice. Direct intraoperative electrical stimulation of injured nerve tissue proximal to the site of repair has been demonstrated to enhance and accelerate functional recovery11,12, suggesting a novel nonpharmacological, bioelectric form of therapy that could complement existing surgical approaches. A significant limitation of this technique is that existing protocols are constrained to intraoperative use and limited therapeutic benefits13. Herein we introduce (i) a platform for wireless, programmable electrical peripheral nerve stimulation, built with a collection of circuit elements and substrates that are entirely bioresorbable and biocompatible, and (ii) the first reported demonstration of enhanced neuroregeneration and functional recovery in rodent models as a result of multiple episodes of electrical stimulation of injured nervous tissue.


Assuntos
Estimulação Elétrica/métodos , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/terapia , Cicatrização/fisiologia , Implantes Absorvíveis/normas , Estimulação Elétrica/instrumentação , Humanos , Traumatismos dos Nervos Periféricos/fisiopatologia , Recuperação de Função Fisiológica , Tecnologia sem Fio
10.
Small ; 14(12): e1703334, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29394467

RESUMO

This paper introduces super absorbent polymer valves and colorimetric sensing reagents as enabling components of soft, skin-mounted microfluidic devices designed to capture, store, and chemically analyze sweat released from eccrine glands. The valving technology enables robust means for guiding the flow of sweat from an inlet location into a collection of isolated reservoirs, in a well-defined sequence. Analysis in these reservoirs involves a color responsive indicator of chloride concentration with a formulation tailored to offer stable operation with sensitivity optimized for the relevant physiological range. Evaluations on human subjects with comparisons against ex situ analysis illustrate the practical utility of these advances.


Assuntos
Colorimetria/métodos , Microfluídica/métodos , Polímeros/química , Suor/química , Humanos , Dispositivos Lab-On-A-Chip , Pele/metabolismo
11.
J Recept Signal Transduct Res ; 37(2): 189-199, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27401208

RESUMO

PURPOSE: The transforming growth factor-beta (TGF-ß) pathway is an important in the initiation and progression of cancer. Due to a strong association between an elevated colorectal cancer risk and increase fecal excretion of cholest-4-en-3-one, we aim to determine the effects of cholest-4-en-3-one on TGF-ß signaling in the mink lung epithelial cells (Mv1Lu) and colorectal cancer cells (HT29) in vitro. METHODS: The inhibitory effects of cholest-4-en-3-one on TGF-ß-induced Smad signaling, cell growth inhibition, and the subcellular localization of TGF-ß receptors were investigated in epithelial cells using a Western blot analysis, luciferase reporter assays, DNA synthesis assay, confocal microscopy, and subcellular fractionation. RESULTS: Cholest-4-en-3-one attenuated TGF-ß signaling in Mv1Lu cells and HT29 cells, as judged by a TGF-ß-specific reporter gene assay of plasminogen activator inhibitor-1 (PAI-1), Smad2/3 phosphorylation and nuclear translocation. We also discovered that cholest-4-en-3-one suppresses TGF-ß responsiveness by increasing lipid raft and/or caveolae accumulation of TGF-ß receptors and facilitating rapid degradation of TGF-ß and thus suppressing TGF-ß-induced signaling. CONCLUSIONS: Our results suggest that cholest-4-en-3-one inhibits TGF-ß signaling may be due, in part to the translocation of TGF-ß receptor from non-lipid raft to lipid raft microdomain in plasma membranes. Our findings also implicate that cholest-4-en-3-one may be further explored for its potential role in colorectal cancer correlate to TGF-ß deficiency.


Assuntos
Neoplasias Colorretais/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fator de Crescimento Transformador beta1/genética , Animais , Colestenonas/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Células Epiteliais/patologia , Células HT29 , Humanos , Pulmão/patologia , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/genética , Microdomínios da Membrana/metabolismo , Vison/genética , Fosforilação , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Proteólise/efeitos dos fármacos , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/biossíntese
12.
Nanoscale Res Lett ; 11(1): 509, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27864818

RESUMO

In this study, effects of the thickness of a low temperature (LT) buffer and impurity incorporation on the characteristics of Nitrogen (N)-polar GaN are investigated. By using either a nitridation or thermal annealing step before the deposition of a LT buffer, three N-polar GaN samples with different thicknesses of LT buffer and different impurity incorporations are prepared. It is found that the sample with the thinnest LT buffer and a nitridation step proves to be the best in terms of a fewer impurity incorporations, strong PL intensity, fast mobility, small biaxial strain, and smooth surface. As the temperature increases at ~10 K, the apparent donor-acceptor-pair band is responsible for the decreasing integral intensity of the band-to-band emission peak. In addition, the thermal annealing of the sapphire substrates may cause more impurity incorporation around the HT-GaN/LT-GaN/sapphire interfacial regions, which in turn may result in a lower carrier mobility, larger biaxial strain, larger bandgap shift, and stronger yellow luminescence. By using a nitridation step, both a thinner LT buffer and less impurity incorporation are beneficial to obtaining a high quality N-polar GaN.

13.
Kaohsiung J Med Sci ; 31(7): 337-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26162813

RESUMO

We investigated the effects of extracorporeal shockwave therapy (ESWT) on the rehabilitation of cervical spondylosis with nuchal ligament (NL) calcification under X-ray and ultrasound guidance. Sixty patients with cervical spondylosis and calcification of NL were selected and randomly assigned to three groups: A, B, and C. Patients in Group A received rehabilitation with 20 minutes of hot packs and underwent 15 minutes of intermittent cervical traction three times/week for 6 weeks. Patients in Group B received the same rehabilitation as those in Group A and ESWT (2000 impulses, 0.27 mJ/mm(2)) over the calcified NL guided by X-ray image. Patients in Group C received the same treatment as those in Group B, but the ESWT was guided by musculoskeletal sonography. The therapeutic effects were evaluated by: changes in range of motion (ROM) of the cervical spine including flexion, extension, lateral bending, and rotation; visual analog pain scale; and Neck Disability Index before and after treatment and at follow up 3 months later. We found a significant reduction in pain in each treated group after treatment and at follow up. However, patients in Groups B and C showed more improvements in ROM and neck pain relief after treatment and a decrease in Neck Disability Index. Furthermore, patients in Group C showed better cervical ROM at follow up than Group B. ESWT is an adjuvant treatment in the management of cervical spondylosis with calcification of NL and ultrasound-guided ESWT results in more functional improvements.


Assuntos
Calcinose/diagnóstico por imagem , Calcinose/terapia , Ligamentos/diagnóstico por imagem , Litotripsia , Espondilose/diagnóstico por imagem , Espondilose/terapia , Calcinose/fisiopatologia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/fisiopatologia , Seguimentos , Humanos , Ligamentos/fisiopatologia , Cervicalgia/diagnóstico por imagem , Cervicalgia/fisiopatologia , Cervicalgia/terapia , Medição da Dor , Radiografia , Amplitude de Movimento Articular , Espondilose/fisiopatologia , Resultado do Tratamento , Ultrassonografia
14.
J Dermatol Sci ; 78(2): 108-16, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25766763

RESUMO

BACKGROUND: AMP-activated protein kinase (AMPK), a principal intracellular energy sensor, plays a crucial role in cell growth, proliferation, apoptosis and autophagy. Imiquimod (IMQ) directly exhibits anti-tumor activity through the induction of apoptosis and autophagic cell death. OBJECTIVE: To evaluate the role of AMPK in IMQ-induced apoptosis and autophagy. METHODS: The phosphorylation of AMPK and its substrates was detected by immunoblotting. ATP contents were analyzed by an ATP bioluminescence assay. The upstream signaling for AMPK activation was dissected by examination of TLR7/8 expression, over-expression of TLR7/8, the addition of AMPK kinase inhibitors, and the genetic silencing of Myd88 and LKB1. The role of AMPK activation in IMQ-induced autophagy and apoptosis was assessed by inhibiting AMPK, genetically silencing AMPK and over-expressing AMPK dominant-negative mutants. Autophagy and apoptosis were evaluated by a DNA content assay, immunoblotting, EGFP-LC3 puncta detection and acridine orange staining. RESULTS: IMQ could activate AMPK and autophagy in cancer cells not expressing TLR7/8. IMQ caused ATP depletion and induced LKB1-mediated AMPK activation. The down-regulation of AMPK activity via pharmacological inhibition and genetic silencing resulted in reduced IMQ-induced apoptosis but did not influence autophagy, and this rescue effect was associated with the retention of translation factor activity and anti-apoptotic Bcl-2 family member Mcl-1 protein expression levels. CONCLUSION: IMQ induces AMPK activation independent of TLR7/8 expression, resulting in translation inhibition and subsequent apoptosis through ATP depletion and LKB1 signaling, in skin tumor cells.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Aminoquinolinas/farmacologia , Antineoplásicos/farmacologia , Carcinoma Basocelular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Melanoma/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Neoplasias Cutâneas/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Trifosfato de Adenosina/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Basocelular/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Regulação para Baixo , Ativação Enzimática/efeitos dos fármacos , Inativação Gênica , Humanos , Imiquimode , Melanoma/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/metabolismo
15.
PLoS Negl Trop Dis ; 8(10): e3122, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25275652

RESUMO

Japanese encephalitis (JE) is a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). Pigs and water birds are the main amplifying and maintenance hosts of the virus. In this study, we conducted a JEV survey in mosquitoes captured in pig farms and water bird wetland habitats in Taiwan during 2005 to 2012. A total of 102,633 mosquitoes were collected. Culex tritaeniorhynchus was the most common mosquito species found in the pig farms and wetlands. Among the 26 mosquito species collected, 11 tested positive for JEV by RT-PCR, including Cx. tritaeniorhynchus, Cx. annulus, Anopheles sinensis, Armigeres subalbatus, and Cx. fuscocephala. Among those testing positive, Cx. tritaeniorhynchus was the predominant vector species for the transmission of JEV genotypes I and III in Taiwan. The JEV infection rate was significantly higher in the mosquitoes from the pig farms than those from the wetlands. A phylogenetic analysis of the JEV envelope gene sequences isolated from the captured mosquitoes demonstrated that the predominant JEV genotype has shifted from genotype III to genotype I (GI), providing evidence for transmission cycle maintenance and multiple introductions of the GI strains in Taiwan during 2008 to 2012. This study demonstrates the intense JEV transmission activity in Taiwan, highlights the importance of JE vaccination for controlling the epidemic, and provides valuable information for the assessment of the vaccine's efficacy.


Assuntos
Anopheles/virologia , Culex/virologia , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/transmissão , Animais , Aves , Genótipo , Vacinas contra Encefalite Japonesa/imunologia , Epidemiologia Molecular , Filogenia , Suínos , Taiwan , Fatores de Tempo
16.
Theor Appl Genet ; 127(11): 2515-24, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25223543

RESUMO

KEY MESSAGE: A minor QTL for heading date located on the long arm of rice chromosome 1 was delimitated to a 95.0-kb region using near isogenic lines with sequential segregating regions. Heading date and grain yield are two key factors determining the commercial potential of a rice variety. In this study, rice populations with sequential segregating regions were developed and used for mapping a minor QTL for heading date, qHd1. A total of 18 populations in six advanced generations through BC2F6 to BC2F11 were derived from a single BC2F3 plant of the indica rice cross Zhenshan 97 (ZS97)///ZS97//ZS97/Milyang 46. The QTL was delimitated to a 95.0-kb region flanked by RM12102 and RM12108 in the terminal region of the long arm of chromosome 1. Results also showed that qHd1 was not involved in the photoperiodic response, having an additive effect ranging from 2.4 d to 2.9 d observed in near isogenic lines grown in the paddy field and under the controlled conditions of either short day or long day. The QTL had pleiotropic effects on yield traits, with the ZS97 allele delaying heading and increasing the number of spikelets per panicle, the number of grains per panicle and grain yield per plant. The candidate region contains ten annotated genes including two genes with functional information related to the control of heading date. These results lay a foundation for the cloning of qHd1. In addition, this kind of minor QTLs could be of great significance in rice breeding for allowing minor adjustment of heading date and yield traits.


Assuntos
Mapeamento Cromossômico , Pleiotropia Genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Locos de Características Quantitativas , Alelos , Cruzamento , Cromossomos de Plantas , Marcadores Genéticos , Fenótipo , Fotoperíodo
17.
Toxicol Appl Pharmacol ; 267(1): 113-24, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23274516

RESUMO

Compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), has been reported to cause apoptotic cell death in myeloma, breast cancer cells and glioma cells. In this study, we have demonstrated that compound C not only induced autophagy in all tested skin cancer cell lines but also caused more apoptosis in p53 wildtype skin cancer cells than in p53-mutant skin cancer cells. Compound C can induce upregulation, phosphorylation and nuclear translocalization of the p53 protein and upregulate expression of p53 target genes in wildtype p53-expressing skin basal cell carcinoma (BCC) cells. The changes of p53 status were dependent on DNA damage which was caused by compound C induced reactive oxygen species (ROS) generation and associated with activated ataxia-telangiectasia mutated (ATM) protein. Using the wildtype p53-expressing BCC cells versus stable p53-knockdown BCC sublines, we present evidence that p53-knockdown cancer cells were much less sensitive to compound C treatment with significant G2/M cell cycle arrest and attenuated the compound C-induced apoptosis but not autophagy. The compound C induced G2/M arrest in p53-knockdown BCC cells was associated with the sustained inactive Tyr15 phosphor-Cdc2 expression. Overall, our results established that compound C-induced apoptosis in skin cancer cells was dependent on the cell's p53 status.


Assuntos
Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Pirazóis/antagonistas & inibidores , Pirimidinas/antagonistas & inibidores , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/fisiologia , Proteínas Quinases Ativadas por AMP/fisiologia , Apoptose/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Linhagem Celular Tumoral , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Neoplasias Cutâneas/enzimologia
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 27(9): 954-8, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-21906466

RESUMO

AIM: To expresse the Chlamydia pneumoniae Cpn0810 in E.coli BL21, and to study weather could it inducing proinflamatory cytokines including TNF-α and IL-6 in human monocytic (THP-1) and cell apoptosis. METHODS: Polymerase chain reaction(PCR) was used to amplify the Cpn0810 gene, PCR products were purified and cloned into the prokaryotic expression vector pGEX6p-2. The restriction plasmids pGEX6p-2/Cpn0810 confirmed by PCR and sequencing was transformed into E.coli BL21. The recombinant protein was purified with glutathione S-transferase (GST) resin chromatography of Novagen after renaturation. THP-1 cells were stimulated by different concentrations of Cpn0810 and for various durations to test the production and the expression of TNF-α and IL-6 by ELISA. Cell apoptosis was detected in C.pneumoniae Cpn0810 cells by Hoechst33258 fluorescence staining and Cell apoptosis was detected in THP-1 cells by Annexin-V-FITC-propidiu-m iodide (PI) staining. RESULTS: The restriction enzymes cleavage analysis and nucleotide sequencing showed the target gene was successfully inserted into pGEX6p-2 prokaryotic expression vector. Cpn0810 stimulated THP-1 cell to produce proinflamatory cytokines including TNF-α and IL-6 in a dose and time-dependent manner. After THP-1 cells were treated with 10 mg/L Cpn0810 for 24 h, apoptosis with nuclear chromatin fragmentation as well as cell shrinkage was observed by fluorescent staining and microscopy; apoptosis of cell was detected after 24 h in THP-1 cells treated with Cpn0810. CONCLUSION: Cpn0810 recombinant protein could stimulate THP-1 cell to produce and express proinflamatory cytokines including TNF-α and IL-6; After THP-1 cells were treated with 10 mg/L Cpn0810 for 24 h, apoptosis of cell was detected after 24 h in THP-1 cells treated with Cpn0810.


Assuntos
Apoptose/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Chlamydophila pneumoniae/imunologia , Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , Linhagem Celular , Chlamydophila pneumoniae/genética , Humanos , Interleucina-6/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Fator de Necrose Tumoral alfa/metabolismo
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(5 Pt 2): 056612, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12059736

RESUMO

Acoustic propagation and scattering in water containing many parallel air-filled cylinders is studied in an exact manner. Two situations are considered and compared; (1) wave propagating through the array of cylinders, imitating common experimental setups, and (2) wave transmitted from a source located inside the ensemble. We show that waves can be blocked from propagation by disorders in the first scenario, but such an inhibition does not necessarily lead to actual wave localization in the medium. The results indicate that the traditional method may be ambiguous in discerning localization effects. Furthermore, the results reveal the phenomenon of wave localization in a range of frequencies.

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