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1.
Int J Nanomedicine ; 14: 6371-6385, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496692

RESUMO

Background: The phenylboronic acid-functionalized polyamidoamine (PP) was employed as a gene carrier for Dz13 delivery, inducing an obvious anticancer response. Materials and methods: The Dz13 condensation ability of PP was evaluated through gel retardation assay. The cellular uptake mechanism of PP/Dz13 nanoparticles was studied using confocal laser scanning microscope and flow cytometer. The inhibition ability of cell proliferation, migration and invasion was investigated through MTT assay, flow cytometry, wound healing and Transwell migration assays, using hepatocarcinoma cell line HepG2 as a model. Finally, Western blotting analysis was used to detect the signaling pathway associated with the inhibition of cell apoptosis and migration induced by Dz13 delivery. Results: The carrier PP could efficiently condense Dz13 into stable nanoparticles at mass ratios of >1.5. The hydrodynamic diameter and zeta potential of PP/Dz13 nanoparticles were measured to be 204.77 nm and +22.00 mV at a mass ratio of 10.0, respectively. The nanoparticles could realize an efficient cellular uptake in sialic acid-dependent endocytosis manner. Moreover, the nanoparticles exhibited an obvious antiproliferation effect through the induction of cell apoptosis and cell cycle arrest due to the cleavage of c-Jun mRNA. Besides, the suppression of cell migration and invasion could be achieved after the PP/Dz13 transfection, attributing to the decreased expression level of MMP-2 and MMP-9. Conclusion: The PP provided a potential delivery system to achieve the tumor-targeting gene therapy.


Assuntos
Ácidos Borônicos/química , Movimento Celular , DNA Catalítico/administração & dosagem , DNA Catalítico/farmacologia , Poliaminas/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Células Hep G2 , Humanos , Nanopartículas/química , Nanopartículas/ultraestrutura , Espectroscopia de Prótons por Ressonância Magnética , RNA Mensageiro/genética
2.
Int J Syst Evol Microbiol ; 69(10): 3148-3154, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385778

RESUMO

A novel Gram-stain-negative, non-spore-forming, obligate aerobic, motile, rod-shaped, and flagellated bacterium, designated S11R28T, was isolated from the intestinal tract of a Korean shiner, Coreoleuciscus splendidus. Based on 16S rRNA gene sequences, strain S11R28T was identified as member of the genus Undibacterium in class Betaproteobacteria, and was closely related to Undibacterium parvum DSM 23061T (98.49 %). The isolate grew at 4-25 °C, pH 6-9, with 0 % (w/v) NaCl, and grew optimally at 20 °C, pH 8, in the absence of NaCl. The main cellular fatty acids were C16 : 0 and summed features 3 (C16 : 1ω7c and/or C16 : 1ω6c). The strain possessed diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as predominant polar lipids, and ubiquinone Q-8 as a respiratory quinone. The polyamine profile composed of 2-hydroxyputrescine, spermidine, putrescine, and benzoic acid. A genomic DNA G+C content was 51.4 mol%. The average nucleotide identity between strains S11R28T and U. parvum DSM 23061T was 78.66 %. Thus, Undibacterium piscinae can be considered a novel species within the genus Undibacterium with the type strain S11R28T (=KCTC 62668T=JCM 33224T).


Assuntos
Cyprinidae/microbiologia , Intestinos/microbiologia , Oxalobacteraceae/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oxalobacteraceae/isolamento & purificação , Fosfolipídeos/química , Poliaminas/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
3.
Int J Nanomedicine ; 14: 4991-5015, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371943

RESUMO

Purpose: This study evaluates the cytotoxicity of AuNPs coated with polyallylamine (AuNPs-PAA) and conjugated or not to the epidermal growth factor receptor (EGFR)-targeting antibody Cetuximab (AuNPs-PAA-Ctxb) in normal human kidney (HK-2), liver (THLE-2) and microvascular endothelial (TIME) cells, and compares it with two cancer cell lines that are EGFR-overexpressing (A431) or EGFR-negative (MDA-MB-453). Results: Conjugation of Cetuximab to AuNPs-PAA increased the AuNPs-PAA-Ctxb interactions with cells, but reduced their cytotoxicity. TIME cells exhibited the strongest reduction in viability after exposure to AuNPs-PAA(±Ctxb), followed by THLE-2, MDA-MB-453, HK-2 and A431 cells. This cell type-dependent sensitivity was strongly correlated to the inhibition of thioredoxin reductase (TrxR) and glutathione reductase (GR), and to the depolarization of the mitochondrial membrane potential. Both are suggested to initiate apoptosis, which was indeed detected in a concentration- and time-dependent manner. The role of oxidative stress in AuNPs-PAA(±Ctxb)-induced cytotoxicity was demonstrated by co-incubation of the cells with N-acetyl L-cysteine (NAC), which significantly decreased apoptosis and mitochondrial membrane depolarization. Conclusion: This study helps to identify the cells and tissues that could be sensitive to AuNPs and deepens the understanding of the risks associated with the use of AuNPs in vivo.


Assuntos
Antioxidantes/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cetuximab/farmacologia , Endocitose/efeitos dos fármacos , Glutationa Redutase/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Tamanho da Partícula , Poliaminas/química , Substâncias Protetoras/farmacologia , Eletricidade Estática , Tiorredoxina Dissulfeto Redutase/metabolismo
4.
Biomater Sci ; 7(9): 3918-3925, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322162

RESUMO

Polymer gels can be classified as chemical and physical gels, depending on the type of cross-link. Physical gels usually form by physical cross-linking, such as hydrogen bonding, van der Waals and/or p-p interactions, which can avoid the use of additional cross-linking agents. Polyamidoamine (PAMAM) dendrimers possess abundant active groups on their surfaces. Modified dendrimers have been used as versatile linkers in some projects. In this work, polymer gels composed of PAMAM dendrimers without any covalent bonding cross-linking agents were prepared. The number of amino groups and ester groups on the surface of the dendrimers was precisely regulated to help form hydrogen bonds between adjacent dendrimers. The prepared dendrimer-based polymer gels retain the properties of PAMAM dendrimers such as antibacterial properties, and the unique structures make the gels exhibit high compressive strengths but relatively low tensile strengths. Interestingly, the prepared gels show good anti-inflammatory properties in acute inflammation models of mice with ear edema. The inflammatory inhibition rate and hematoxylin-eosin (H&E) staining method were used to confirm the anti-inflammatory effect. This present study demonstrates that the dendrimer-based polymer gels achieved through hydrogen bonding could be a versatile platform for tissue engineering.


Assuntos
Anti-Inflamatórios/farmacologia , Dendrímeros/química , Poliaminas/química , Células 3T3 , Animais , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Dendrímeros/farmacologia , Edema/tratamento farmacológico , Feminino , Géis , Ligações de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , Poliaminas/farmacologia , Resistência à Tração
5.
Eur J Med Chem ; 179: 78-83, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31238252

RESUMO

Rising resistance to conventional therapies for malaria has led to the search for novel drugs and strategies with distinct mechanisms of action that may overcome this. Ferroquine is currently the gold standard as far as antimalarial metal-based drugs are concerned and is currently in phase IIb clinical trials as part of the MMV pipeline (in partnership with Sanofi) of antimalarials. It is assumed to inhibit haemozoin formation like chloroquine and maintain its activity in the resistant strain. Here we report two ferroquine-derived polyamines that target a resistant strain of Plasmodium falciparum. Furthermore, upon treatment of Plasmodium falciparum with a ferroquine-derived polyamine, cellular haem fractionation experiments reveal that the inhibition of haemozoin formation is likely not the mechanism responsible for their activity, an important result to aid further clinical development.


Assuntos
Aminoquinolinas/farmacologia , Antimaláricos/farmacologia , Farmacorresistência Fúngica/efeitos dos fármacos , Compostos Ferrosos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Poliaminas/farmacologia , Aminoquinolinas/química , Animais , Antimaláricos/síntese química , Antimaláricos/química , Células CHO , Cricetulus , Relação Dose-Resposta a Droga , Resistência a Medicamentos/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Compostos Ferrosos/química , Estrutura Molecular , Testes de Sensibilidade Parasitária , Poliaminas/síntese química , Poliaminas/química , Relação Estrutura-Atividade
6.
Int J Syst Evol Microbiol ; 69(8): 2179-2186, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31204973

RESUMO

Two Gram-stain-negative bacterial strains, DS48-3T and CH68-4T, were isolated from freshwater sediment taken from the Daechung Reservoir, Republic of Korea. Cells of strains DS48-3T and CH68-4T were aerobic, non-motile, non-spore-forming and rod-shaped. Strain DS48-3T was isolated from a sediment surface sample at a depth of 48 m from the Daechung Reservoir and was most closely related to the genus Sphingopyxis according to 16S rRNA gene sequence analysis (94.5-95.9 % similarity). Strain CH68-4T was isolated from the very bottom of a 67-cm-long sediment core collected from Daechung Reservoir at a water depth of 17 m and was most closely related to the genus Sphingopyxis (16S rRNA gene sequence similarity of 93.7-95.0 %). Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the two strains formed a separate lineage within the order Sphingomonadales showing similarity values below 95.9 % with their closest phylogenetic neighbours, and sharing 97.3 % similarity with each other. The combined genotypic and phenotypic data showed that strains DS48-3T and CH68-4T could be distinguished from all genera within the family Sphingomonadaceae and represented two distinct species of a novel genus, Aquisediminimonas profunda gen. nov., sp. nov. (type strain DS48-3T=KCTC 52068T=CCTCC AB 2018061T) and Aquisediminimonas sediminicola sp. nov. (type strain CH68-4T=KCTC 62205T=CCTCC AB 2018062T).


Assuntos
Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Filogenia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Poliaminas/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Sphingomonadaceae/isolamento & purificação , Ubiquinona/análogos & derivados , Ubiquinona/química
7.
Plant Physiol Biochem ; 141: 431-445, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31238253

RESUMO

S-adenosylmethionine synthetase (SAMS) catalyzes methionine and ATP to generate S-adenosyl-L-methionine (SAM). In plants, accumulating SAMS genes have been characterized and the majority of them are reported to participate in development and stress response. In this study, two putative SAMS genes (CsSAMS1 and CsSAMS2) were identified in cucumber (Cucumis Sativus L.). They displayed 95% similarity and had a high identity with their homologous of Arabidopsis thaliana and Nicotiana tabacum. The qRT-PCR test showed that CsSAMS1 was predominantly expressed in stem, male flower, and young fruit, whereas CsSAMS2 was preferentially accumulated in stem and female flower. And they displayed differential expression profiles under stimuli, including NaCl, ABA, SA, MeJA, drought and low temperature. To elucidate the function of cucumber SAMS, the full-length CDS of CsSAMS1 was cloned, and prokaryotic expression system and transgenic materials were constructed. Expressing CsSAMS1 in Escherichia coli BL21 (DE3) improved the growth of the engineered strain under salt stress. Overexpression of CsSAMS1 significantly increased MDA content, H2O2 content, and POD activity in transgenic lines under non-stress condition. Under salt stress, however, the MDA content of transgenic lines was lower than that of the wild type, the H2O2 content remained high, the polyamine and ACC synthesis in transgenic lines exhibited a CsSAMS1-expressed dependent way. Taken together, our results suggested that both CsSAMS1 and CsSAMS2 were involved in plant development and stress response, and a proper increase of expression level of CsSAMS1 in plants is benificial to improving salt tolerance.


Assuntos
Cucumis sativus/enzimologia , Cucumis sativus/fisiologia , Metionina Adenosiltransferase/metabolismo , Tolerância ao Sal , Antioxidantes/metabolismo , Arabidopsis/metabolismo , Secas , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/química , Metionina Adenosiltransferase/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Poliaminas/química , Sais , Estresse Mecânico , Estresse Fisiológico/genética , Tabaco/metabolismo
8.
Int J Syst Evol Microbiol ; 69(8): 2372-2379, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31157614

RESUMO

Strain WWJ-16T was isolated from a freshwater reservoir in Taiwan. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain WWJ-16T is affiliated with the species in the genus Flavobacterium. Strain WWJ-16T was most closely related to Flavobacterium fontis MIC3010T (97.9 % 16S rRNA gene sequence identity) and Flavobacterium squillarum CMJ-5T (97.6 %). Strain WWJ-16T showed 77.4 % average nucleotide identity and 20.6 % digital DNA-DNA hybridization identity with F. fontis MIC3010T. Cells of strain WWJ-16T were Gram-stain-negative, strictly aerobic, non-motile, rod-shaped and formed yellow colonies. Optimal growth occurred at 25 °C, pH 7 and in 0.5-1 % NaCl (w/v). Strain WWJ-16T contained iso-C15 : 1 G and iso-C15 : 0 as predominant fatty acids. The major hydroxyl fatty acids were iso-C15 : 0 3-OH, iso-C17 : 0 3-OH and iso-C16 : 0 3-OH. The polar lipid profile consisted of phosphatidylethanolamine, four uncharacterized aminophospholipids and four uncharacterized phospholipids. The major polyamine was homospermidine. The major isoprenoid quinone was MK-6. The genomic DNA G+C content of strain WWJ-16T was 39.4 mol%, as determined by genome sequencing. The genotypic and phenotypic characteristics indicate that strain WWJ-16T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium stagni sp. nov. is proposed. The type strain is WWJ-16T (=BCRC 81125T =LMG 30600T=KCTC 62515T).


Assuntos
Flavobacterium/classificação , Água Doce/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Chemistry ; 25(44): 10375-10384, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31090112

RESUMO

The ester bond as a universal linker has recently been applied in gene delivery systems owing to its efficient gene release by electrostatic repulsion after its cleavage. However, the ester bond is nonlabile and is difficult to cleave in cells. This work reports a method in which a secondary amine was introduced to the ß-position of the ester bond to generate a hydrogen-bond cyclization (HBC) structure that can make the ester bond hydrolysis ultrafast. A series of molecules comprising ultrasensitive esters that can be activated by H2 O2 were synthesized, and it was found that those able to form an HBC structure showed complete ester hydrolysis within 5 h in both water and phosphate-buffered saline solution, which was several times faster than other methods reported. Then, a series of amphiphilic poly(amidoamine) dendrimers were constructed, comprising the ultrasensitive ester groups for gene delivery; it was found that they could effectively release genes under quite a low concentration of H2 O2 (<200 µm) and transport them into the nucleus within 2 h in Hela cells with high safety. Their gene transfection efficiencies were higher than that of PEI25k . The results demonstrated that the hydrogen-bond-induced ultrasensitive esters could be powerfully applied to construct gene delivery systems.


Assuntos
DNA/química , Dendrímeros/química , Ésteres/química , Técnicas de Transferência de Genes , Poliaminas/química , Linhagem Celular Tumoral , Sobrevivência Celular , Ciclização , DNA/administração & dosagem , Proteínas de Fluorescência Verde/genética , Humanos , Ligações de Hidrogênio , Peróxido de Hidrogênio/química , Hidrólise , Cinética , Transfecção
10.
Int J Syst Evol Microbiol ; 69(8): 2283-2291, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31120829

RESUMO

Strain LLJ-11T, isolated from water sampled from a freshwater stream in Taiwan, was characterized using a polyphasic taxonomy approach. Cells of strain LLJ-11T were Gram-stain-negative, strictly aerobic, motile by gliding, rod-shaped and formed translucent yellow colonies. Optimal growth occurred at 25 °C, pH 7 and 0 % NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain LLJ-11T is affiliated with species in the genus Flavobacterium. Strain LLJ-11T was most closely related to Flavobacterium amniphilum KYPY10T with 98.0 % 16S rRNA gene sequence identity. The DNA-DNA relatedness of strain LLJ-11T with respect to Flavobacterium species was less than 35 %. Average nucleotide identity and digital DNA-DNA hybridization values between strain LLJ-11T and the type strains of other closely related Flavobacterium species were 70.0-76.3 % and 21.1-23.9 %, respectively. Strain LLJ-11T contained iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and summed feature 9 (iso-C17 : 1ω9c and/or 10-methyl C16 : 0) as the predominant fatty acids. The major isoprenoid quinone was MK-6. The polar lipid profile consisted of phosphatidylethanolamine, three uncharacterized aminophospholipids and two uncharacterized phospholipids. The major polyamine was homospermidine. The DNA G+C content was 34.8 mol%. On the basis of the phylogenetic inference and phenotypic data, strain LLJ-11T is considered a representative of a novel species within the genus Flavobacterium. The name Flavobacterium amnicola sp. nov. is proposed, with strain LLJ-11T (=BCRC 81124T=LMG 30599T=KCTC 62514T) as the type strain.


Assuntos
Flavobacterium/classificação , Filogenia , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Água Doce/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Nanomedicine ; 14: 3189-3201, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118631

RESUMO

Purpose: Early diagnosis is essential for reducing liver cancer mortality, and molecular diagnosis by magnetic resonance imaging (MRI) is an emerging and promising technology. The chief aim of the present work is to use the ferritin gene, modified by the alpha-fetoprotein (AFP) promoter, carried by a highly safe vector, to produce signal contrast on T2-weighted MR imaging as an endogenous contrast agent, and to provide a highly specific target for subsequent therapy. Methods: Polyethyleneimine-ß-cyclodextrin (PEI-ß-CD, PC) was synthesized as a novel vector. The optimal nitrogen/phosphorus ratio (N/P) of the PC/plasmid DNA complex was determined by gel retardation, biophysical properties and transmission electron microscopy morphological analysis. The transfection efficiency was observed under a fluorescence microscope and analyzed by flow cytometry. Cellular iron accumulation caused by ferritin overexpression was verified by Prussian blue staining, and the resulting contrast imaging effect was examined by MRI. Results: The modified cationic polymer PC was much safer than high molecular weight PEI, and could condense plasmid DNA at an N/P ratio of 50 with suitable biophysical properties and a high transfection efficiency. Overexpression of ferritin enriched intracellular iron. The short-term iron imbalance initiated by AFP promoter regulation only occurred in hepatoma cells, resulting in signal contrast on MRI. The specific target TfR was also upregulated during this process. Conclusion: These results illustrate that the regulated ferritin gene carried by PC can be used as an endogenous contrast agent for MRI detection of hepatocellular carcinoma (HCC). This molecular imaging technique may promote safer early diagnosis of HCC, and provide a more highly specific target for future chemotherapy drugs.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Ferritinas/genética , Neoplasias Hepáticas/diagnóstico por imagem , Imagem por Ressonância Magnética , Imagem Molecular/métodos , Poliaminas/química , Carcinoma Hepatocelular/patologia , Morte Celular , Linhagem Celular Tumoral , DNA/metabolismo , Células HEK293 , Humanos , Ferro/metabolismo , Neoplasias Hepáticas/patologia , Tamanho da Partícula , Plasmídeos/metabolismo , Polietilenoimina/química , Regiões Promotoras Genéticas , Espectroscopia de Prótons por Ressonância Magnética , Receptores da Transferrina/metabolismo , Eletricidade Estática
12.
Environ Sci Pollut Res Int ; 26(18): 18098-18112, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31037538

RESUMO

Water pollution caused by Cr(III) is a serious environmental problem which bring adverse effect to environmental protection and public safety. Efficient removal of Cr(III) from aqueous solution is important for the remediation of Cr(III) pollution. Herein, a series of silica-gel/polyamidoamine (PAMAM) dendrimer hybrid materials (SG-G0~SG-G4.0) were used for the removal of Cr(III) from aqueous solution. The factors that affect the adsorption were extensively studied and the adsorption mechanism was demonstrated based on the experimental results and density functional theory (DFT) calculation. Result demonstrates the adsorption capacity of ester-terminated silica-gel/PAMAM dendrimers follow the order of SG-G2.5 > SG-G3.5 > SG-G1.5 > SG-G0.5, while that of amino-terminated ones decrease in the order of SG-G2.0 > SG-G4.0 > SG-G3.0 > SG-G1.0 > SG-G0. The highest adsorption is achieved at pH 4.0 for both ester- and amino-terminated materials. Adsorption kinetic indicates the adsorption equilibrium can be reached at about 240 and 180 min for amino- and ester-terminated hybrids, respectively. Adsorption kinetic can be well fitted by pseudo-second-order kinetic model with film diffusion process as the rate-limiting step. Adsorption isotherm follows Langmuir model with monolayer adsorption behavior. Fourier transform infrared spectra (FTIR) indicate the adsorption of Cr(III) by PAMAM dendrimer mainly involve the participation of N-H and C=O groups. DFT calculation demonstrates the uptake of Cr(III) by ester-terminated adsorbents mainly involves carbonyl oxygen and secondary amine nitrogen atoms to form tetra-coordinated chelate, while that of amino-terminated one tends to form hexa-coordinated chelates by carbonyl oxygen, primary and secondary amine nitrogen atoms.


Assuntos
Cromo/isolamento & purificação , Dendrímeros/química , Poliaminas/química , Sílica Gel/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Difusão , Cinética , Água
13.
Int J Syst Evol Microbiol ; 69(7): 2153-2160, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31120830

RESUMO

Strain CCP-7T, isolated from a freshwater pond in Taiwan, was characterized using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain CCP-7T formed a phylogenetic lineage in the genus Sphingomonas. Strain CCP-7T was most closely related to Sphingomonas starnbergensis 382T and Sphingomonas naphthae DKC-5-1T with 96.2 % 16S rRNA gene sequence similarity. Strain CCP-7T showed 65.5-76.7 % average nucleotide identity and 20.2-22.5 % digital DNA-DNA hybridization identity with the strains of other related Sphingomonas species. Cells were Gram-stain-negative, aerobic, motile, rod-shaped and formed light orange-coloured colonies. Optimal growth occurred at 30 °C, pH 6 and in the absence of NaCl. The major fatty acid of strain CCP-7T was C18 : 1ω7c. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylmonomethylethanolamine, three uncharacterized sphingoglycolipids, two uncharacterized phospholipids and six uncharacterized lipids. The predominant polyamine was homospermidine. The only isoprenoid quinone was Q-10. Genomic DNA G+C content of strain CCP-7T was 64.5 %. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain CCP-7T should be classified in a novel species of the genus Sphingomonas, for which the name Sphingomonas crocodyli sp. nov. is proposed. The type strain is CCP-7T (=BCRC 81096T=LMG 30311T=KCTC 62190T).


Assuntos
Filogenia , Tanques/microbiologia , Sphingomonas/classificação , Jacarés e Crocodilos , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonas/isolamento & purificação , Taiwan , Ubiquinona/análogos & derivados , Ubiquinona/química
14.
Mater Sci Eng C Mater Biol Appl ; 101: 190-203, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029312

RESUMO

Besides their use for drug and gene delivery, dendrimer molecules are also favorable for the design of new surface coatings for orthopedic and dental implants due to the wide variety of functional terminal groups and their multivalent character. The purpose of this work was to observe how covalently immobilized polyamidoamine (PAMAM) dendrimer molecules with different terminal chemical groups influenced serum protein adsorption and osteoblast behavior. To this end, fifth-generation PAMAM dendrimers were immobilized on silicon surfaces with an anhydride-containing silane coupling agent which results in positively charged terminal NH2-groups. Coatings with a net negative charge were generated by introduction of terminal CO2H- or CH3-groups. Surface characterization was performed by static and dynamic contact angle and zeta potential. The in vitro studies with human MG-63 osteoblastic cells focused on cell adhesion, morphology, cell cycle, apoptosis and actin formation within 24 h. This work demonstrated that cell growth was dependent on surface chemistry and correlated strongly with the surface free energy and charge of the material. The positively charged NH2 surface induced tight cell attachment with well-organized actin stress fibers and a well spread morphology. In contrast, CO2H- and CH3-functional groups provoked a decrease in cell adhesion and spreading and indicated higher apoptotic potential, although both were hydrophilic. The knowledge about the cell-material dialogue is of relevance for the development of bioactive implants in regenerative medicine.


Assuntos
Dendrímeros/química , Dendrímeros/farmacologia , Osteócitos/citologia , Poliaminas/química , Poliaminas/farmacologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Adsorção , Apoptose/efeitos dos fármacos , Proteínas Sanguíneas/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteócitos/efeitos dos fármacos , Silício/farmacologia , Eletricidade Estática , Propriedades de Superfície , Água/química
15.
Sensors (Basel) ; 19(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010258

RESUMO

A new electrochemical immunosensor for cancer cell detection based on a specific interaction between the metastasis-related antigen of epithelial cell adhesion molecule (EpCAM) on the cell membrane and its monoclonal antibody (Anti-EpCAM) immobilized on a gold electrode has been developed. The amino-terminated polyamidoamine dendrimer (G6 PAMAM) was first covalently attached to the 3-mercaptopropionic acid (MPA)-functionalized gold electrode to obtain a thin film, and then completely carboxylated by succinic anhydride (SA). Next, the Anti-EpCAM was covalently bound with the G6 PAMAM to obtain a stable recognition layer. In the presence of the EpCAM expressing hepatocellular carcinomas cell line of HepG2, the specific immune recognition (Anti-EpCAM/EpCAM) led to an obvious change of the electron transfer ability. The properties of the layer-by-layer assembly process was examined by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The final determination of HepG2 cells was performed in the presence of the reversible [Fe(CN)6]3-/4- redox couple using impedance technique. Based on the advantages of PAMAM nanomaterial and immune reaction, a linear response to HepG2 cells ranging from 1 × 104 to 1 × 106 cells mL-1 with a calculated detection limit of 2.1 × 103 cells mL-1 was obtained. We expect this method can provide a potential tool for cancer cell monitoring and protein expression analysis.


Assuntos
Técnicas Biossensoriais , Molécula de Adesão da Célula Epitelial/genética , Imunoensaio , Neoplasias Hepáticas/genética , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Membrana Celular/química , Membrana Celular/imunologia , Dendrímeros/química , Espectroscopia Dielétrica , Molécula de Adesão da Célula Epitelial/química , Molécula de Adesão da Célula Epitelial/imunologia , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/imunologia , Nanoestruturas/química , Poliaminas/química
16.
Anal Bioanal Chem ; 411(13): 2925-2935, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30957202

RESUMO

We present an electrochemical DNA detection strategy based on self-assembled ferrocene-cored poly(amidoamine) dendrimers for the detection of a gene relevant to breast cancer. The chemisorption of three ferrocene-cored poly(amidoamine) generations and hybridization of single-stranded DNA on a Au electrode were studied by cyclic voltammetry and differential pulse voltammetry. The biosensor demonstrated high sensitivity of 0.13 µA/(ng/ml) in the detection of the target DNA with a linear range of 1.3-20 nM and a detection limit of 0.38 nM. The DNA biosensor also has high selectivity for the target DNA, showing a clear signal difference from a noncomplementary sequence and a single-base-mismatch sequence, which was used as a model of BRAC1 gene mutation. The results shown are highly motivating for exploring DNA biosensing technology in the diagnosis of breast cancer caused by mutation of the BRAC1 gene. Graphical abstract.


Assuntos
Técnicas Biossensoriais/métodos , Neoplasias da Mama/genética , DNA/genética , Técnicas Eletroquímicas/métodos , Genes BRCA1 , Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Análise Mutacional de DNA/métodos , DNA de Cadeia Simples/genética , Feminino , Compostos Ferrosos/química , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/genética , Metalocenos/química , Mutação , Hibridização de Ácido Nucleico , Poliaminas/química
17.
Int J Syst Evol Microbiol ; 69(6): 1775-1782, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30964429

RESUMO

Strain ICH-30T was isolated from a freshwater fish pond in Taiwan. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain ICH-30T formed a phylogenetic lineage in the genus Flavobacterium. Strain ICH-30T was most closely related to Flavobacteriumlacus NP180T with 97.0 % 16S rRNA gene sequence similarity. Strain ICH-30T showed 70.0-83.1 % average nucleotide identity and 16.5-23.7 % digital DNA-DNA hybridization identity with the type strains of other closely related Flavobacterium species. Cells of strain ICH-30T were Gram-stain-negative, strictly aerobic, non-motile, rod-shaped and formed dark orange colonies. Optimal growth occurred at 20-30 °C, pH 8-9 and 0-0.5 % NaCl. Strain ICH-30T contained iso-C15 : 1 G and iso-C15 : 0 as the predominant fatty acids. The major hydroxyl fatty acids were iso-C17 : 0 3-OH, iso-C16 : 0 3-OH and iso-C15 : 0 3-OH. The polar lipid profile consisted of phosphatidylethanolamine, six uncharacterized aminophospholipids, one uncharacterized phospholipid and two uncharacterized lipids. The major polyamine was homospermidine. The only isoprenoid quinone was MK-6. The DNA G+C content of the genomic DNA was 34.3 mol%. On the basis of the phylogenetic inference and phenotypic data, strain ICH-30T should be classified as a novel species, for which the name Flavobacterium piscinae sp. nov. is proposed. The type strain is ICH-30T (=BCRC 81122T=LMG 30579T=KCTC 62513T).


Assuntos
Peixes , Flavobacterium/classificação , Filogenia , Tanques/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Água Doce/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
Int J Syst Evol Microbiol ; 69(6): 1705-1713, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31033432

RESUMO

A bacterial strain, BBQ-12T, was isolated from a freshwater lake in Taiwan. The strain was Gram-stain-negative, strictly aerobic, motile by gliding, rod-shaped and formed yellow colonies. Optimal growth occurred at 25 °C, pH 6 and in the absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain BBQ-12T formed a phylogenetic lineage in the genus Flavobacterium. Strain BBQ-12T was most closely related to Flavobacterium fluminis 3R17T with 98.1 % 16S rRNA gene sequence similarity. Strain BBQ-12T showed 74.4-83.1 % average nucleotide identity and 16.0-21.8 % digital DNA-DNA hybridization identity with the type strains of other closely related Flavobacterium species. Strain BBQ-12T contained iso-C15 : 0, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and anteiso-C15 : 0 as the predominant fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, four uncharacterized aminophospholipids and three uncharacterized phospholipids. The major polyamine was homospermidine. The major isoprenoid quinone was MK-6. The DNA G+C content of the genomic DNA was 34.2 mol%. Differential phenotypic properties, together with the phylogenetic inference, demonstrate that strain BBQ-12T should be classified as a novel species of the genus Flavobacterium, for which the name Flavobacteriumsufflavum sp. nov. is proposed. The type strain is BBQ-12T (=BCRC 81049T=LMG 30051T=KCTC 52809T).


Assuntos
Flavobacterium/classificação , Lagos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Sensors (Basel) ; 19(6)2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30934546

RESUMO

Second-generation glucose biosensors are presently the mainstream commercial solution for blood glucose measurement of diabetic patients. Screen-printed carbon electrodes (SPCEs) are the most-used substrate for glucose testing strips. This study adopted hydrophilic and positively charged α-poly-l-lysine (αPLL) as the entrapment matrix for the immobilization of negatively charged glucose oxidase (GOx) and ferricyanide (FIC) on SPCEs to construct a disposable second-generation glucose biosensor. The αPLL modification is shown to facilitate the redox kinetics of FIC and ferrocyanide on the SPCEs. The SPCEs coated with 0.5 mM GOx, 99.5 mM FIC, and 5 mM αPLL had better sensitivity for glucose detection due to the appreciable effect of protonated αPLL on the promotion of electron transfer between GOx and FIC. Moreover, the SPCEs coated with 0.5 mM GOx, 99.5 mM FIC, and 5 mM αPLL were packaged as blood glucose testing strips for the measurement of glucose-containing human serum samples. The glucose testing strips had good linearity from 2.8 mM to 27.5 mM and a detection limit of 2.3 mM. Moreover, the 5 mM αPLL-based glucose testing strips had good long-term stability to maintain GOx activity in aging tests at 50 °C.


Assuntos
Glicemia/análise , Técnicas Eletroquímicas/métodos , Ferricianetos/química , Glucose Oxidase/química , Polilisina/química , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucose Oxidase/metabolismo , Humanos , Limite de Detecção , Oxirredução , Sistemas Automatizados de Assistência Junto ao Leito , Poliaminas/química , Reprodutibilidade dos Testes
20.
Int J Syst Evol Microbiol ; 69(6): 1546-1550, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30932804

RESUMO

A Gram-stain-negative, catalase- and oxidase-positive, non-motile bacterium, designated F02T, was isolated from of gut of Cincticostellalevanidovae (Tshernova). Growth occurred at a temperature range of 4-30 °C, at pH 6-9 and in the presence of 0-0.5 % (w/v) NaCl. Phylogenetic analysis demonstrated that the 16S rRNA gene sequence of strain F02T shared the highest similarity to that of the type strain of Hydromonas duriensis A2P5T (96.82 %). The major isoprenoid quinone was Q-8. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major cellular fatty acids were summed feature 3 (C16 : 1ω7c/C16 : 1ω6c) and iso-C13 : 0 3-OH. The polyamines were cadaverine and putrescine. Combined data from phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strain F02T represents a novel genus and species, for which the name Ephemeroptericolacinctiostellae gen. nov., sp. nov. is proposed. The type strain of Ephemeroptericola cinctiostellae gen. nov., sp. nov. is F02T (=FBCC 500047T=KCTC 62567T=JCM 32722T).


Assuntos
Burkholderiaceae/classificação , Trato Gastrointestinal/microbiologia , Insetos/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Burkholderiaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Poliaminas/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
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