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1.
Langmuir ; 35(20): 6782-6792, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31042867

RESUMO

Membranes for biologically and biomedically related applications must be bioinert, that is, resist biofouling by proteins, human cells, bacteria, algae, etc. Hydrophobic materials such as polysulfone, polypropylene, or poly(vinylidene fluoride) (PVDF) are often chosen as matrix materials but their hydrophobicity make them prone to biofouling, which in turn limits their application in biological/biomedical fields. Here, we designed PVDF-based membranes by precipitation from the vapor phase and zwitterionized them in situ to reduce their propensity to biofouling. To achieve this goal, we used a copolymer containing phosphorylcholine groups. An in-depth physicochemical characterization revealed not only the controlled presence of the copolymer in the membrane but also that bicontinuous membranes could be formed. Membrane hydrophilicity was greatly improved, resulting in the mitigation of a variety of biofoulants: the attachment of Stenotrophomonas maltophilia, Streptococcus mutans, and platelets was reduced by 99.9, 99.9, and 98.9%, respectively. Besides, despite incubation in a plasma platelet-poor medium, rich in plasma proteins, a flux recovery ratio of 75% could be measured while it was only 40% with a hydrophilic commercial membrane of similar structure and physical properties. Similarly, the zwitterionic membrane severely mitigated biofouling by microalgae during their harvesting. All in all, the material/process combination presented in this work leads to antibiofouling porous membranes with a large span of potential biomedically and biologically related applications.

2.
J Microbiol Immunol Infect ; 49(1): 91-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24657070

RESUMO

BACKGROUND/PURPOSE: Interleukin-33 (IL-33) could play an important role in the pathogenesis of angiostrongylosis. However, the role of IL-33/ST2 pathway in this parasitic infection is uncertain. METHODS: C57BL/six mice were each infected with 35 Angiostrongylus cantonensis larvae. One group of mice received an intraperitoneal injection of anti-ST2 monoclonal antibody (mAb; 50 µg) 3 days postinfection and subsequent booster shots of the same dose at 5-day intervals. Blood samples from each group were collected every week for assays. RESULTS: The level of IL-5 significantly decreased in the mAb-treated group, and the infiltration of eosinophils in the meninges was also significantly reduced. CONCLUSION: The IL-33/ST2 axis may play a crucial role in the pathogenesis of angiostrongylosis and the results of this study could be useful for the development of strategies to reduce the neurological damage caused by this parasitic infection.


Assuntos
Angiostrongylus cantonensis/imunologia , Anticorpos Monoclonais/administração & dosagem , Eosinófilos/imunologia , Meninges/patologia , Receptores de Interleucina/antagonistas & inibidores , Infecções por Strongylida/patologia , Animais , Proteína 1 Semelhante a Receptor de Interleucina-1 , Masculino , Camundongos Endogâmicos C57BL , Resultado do Tratamento
3.
J Biomed Nanotechnol ; 11(5): 906-12, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26349402

RESUMO

Hydroxyapatite (HAP: Ca10(PO4)6(OH)2) is a widely used biocompatible material; however, information on the reaction mechanism between HAP and microorganisms is insufficient. This study aimed to identify a stable reference gene for studying the antibacterial activity of HAP. The half maximal inhibitory concentration (C50) and gene expression of a human symbiotic Escherichia coli strain TOP10, was investigated at various concentrations of HAP. Our uniformly sized HAP nanoparticles (HANPs) had a high surface area and an estimated IC50 of 75 mg/mL. The expressions of genes, including those of DNA polymerase I (poIA), DNA polymerase II (poIB), cytochrome d complex (cyd), glucan biosynthesis protein G (mdoG), D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and 16S ribosomal RNA (16S rRNA), were analyzed by performing quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) and using reported and newly designed primers. The changes in the copy numbers compared to non-HANPs-treated conditions for polB, cyd, mdoG, GAPDH, and 16S rRNA were 50%-381%, 0.7%-66.3%, 1.1%-7.8%, 1.6%-86.3%, and 0.3%-8.1%, respectively. The expressions of polA remained stable under all conditions (62.8%-88.4%). Therefore, we identified polA as a suitable reference gene. Moreover, the expressions of cyd and mdoG were inhibited, indicating that the antibacterial activity of HANPs is related to cell membrane or cell wall proteins. Our findings provide a thorough understanding of HAP-microorganism interactions for potential biomedical applications.


Assuntos
Antibacterianos/farmacologia , DNA Polimerase I/genética , Durapatita/farmacologia , Reação em Cadeia da Polimerase em Tempo Real/normas , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/normas , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana/normas , Nanopartículas , RNA Ribossômico 16S/genética , Padrões de Referência
4.
Biomed Res Int ; 2015: 689614, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339633

RESUMO

The present results demonstrated that high glucose (G), salt (S), and cholesterol C (either alone or in combination), as mimicking extracellular changes in metabolic syndrome, damage cardiomyocyte-like H9c2 cells and reduce their viability in a time-dependent manner. However, the effects were greatest when cells were exposed to all three agents (GSC). The mRNA of glycoprotein (gp) 130 and WSX-1, both components of the interleukin (IL)-27 receptor, were present in H9c2 cells. Although mRNA expression was not affected by exogenous treatment with IL-27, the expression of gp130 mRNA (but not that of WSX-1 mRNA) was attenuated by GSC. Treatment of IL-27 to H9c2 cells increased activation of signal transducer and activator of transcription 3 (STAT3) and protected cells from GSC-induced cytochrome c release and cell damage. The protective effects of IL-27 were abrogated by the STAT3 inhibitor, stattic. The results of the present study clearly demonstrate that the STAT3 pathway triggered by anti-inflammatory IL-27 plays a role in protecting cardiomyocytes against GSC-mediated damage.


Assuntos
Inflamação/genética , Interleucinas/farmacologia , Síndrome Metabólica/genética , Miócitos Cardíacos/efeitos dos fármacos , Fator de Transcrição STAT3/biossíntese , Sobrevivência Celular/efeitos dos fármacos , Colesterol/farmacologia , Citocromos c/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Glicoproteínas/biossíntese , Glicoproteínas/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Interleucinas/metabolismo , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , RNA Mensageiro/biossíntese , Receptores de Interleucina/biossíntese , Receptores de Interleucina/metabolismo , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos
5.
Basic Res Cardiol ; 110(3): 22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25820907

RESUMO

Patients with coronary artery disease show high serum levels of interleukin (IL)-27, a novel member of the IL-6 family. However, the function of IL-27 in hearts suffering ischemia/reperfusion (IR) injury is unclear. Here, we showed increased expression of mRNA for the IL-27 subunits, EBI3 and p28, in rat hearts after 40 min of coronary ligation and release for 7 days. This increase was associated with a peak in the release of the cardiac enzyme, creatine kinase-MB, on day 2 post-release. Moreover, levels of IL-27 receptor subunit gp130 mRNA, but not those of subunit WSX-1 mRNA, decreased in post-ischemic hearts. These results suggest that increased IL-27 production may compensate for receptor downregulation during myocardial recovery. Lactate dehydrogenase release and crystal violet staining revealed that IL-27 or IL-6 significantly attenuated severe hypoxia (SH, 2 % O2)-induced cell damage in H9c2 cardiomyoblasts and primary rat neonatal cardiomyocytes. Incubating cardiomyocytes with IL-27 or IL-6 resulted in time-dependent activation of signal transducers and activators of transcription 3 (STAT3). Interestingly, IL-27-induced STAT3 activation was attenuated by pre-treatment with a gp130-neutralizing antibody. Blocking gp130 also reduced the cytoprotective effects of IL-27 or IL-6. Moreover, IL-27-mediated protection against SH was blocked by stattic, a small-molecule inhibitor of STAT3. IL-27 markedly improved post-ischemic recovery and reduced tissue damage in isolated perfused hearts when administered 5 min before reperfusion. These results indicate that IL-27 protects the myocardium against IR injury and facilitates the recovery of damaged cardiomyocytes via the gp130/STAT3 pathway.


Assuntos
Receptor gp130 de Citocina/metabolismo , Interleucinas/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/fisiologia , Animais , Western Blotting , Modelos Animais de Doenças , Reação em Cadeia da Polimerase , Ratos , Ratos Wistar
6.
Bioresour Technol ; 190: 480-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25794809

RESUMO

Simultaneous partial nitrification, anammox and denitrification (SNAD) process was started-up in a 2.5L sequencing batch biofilm reactor (SBBR) using novel biomass carriers. The SNAD process took only 51d for start-up at nitrogen loading rate (NLR) and organic loading rate (OLR) of 120 and 60g/m(3)-d, respectively. Long-term stable operation of SNAD process was observed at NLR and OLR of 360 and 180g/m(3)-d with average total nitrogen and COD removal efficiencies of >88% and >90%, respectively. The values of conversion ratio [Formula: see text] remained below 0.11 after the start-up period, which further confirmed the long-term stability of SNAD process. Results of polymerase chain reaction (PCR), qualitative PCR, and scanning electron microscopic (SEM) analysis of sludge samples confirmed the co-existence and enrichment of AOB, anammox bacteria and denitrifying bacteria in the reactor and biofilm formation on to the carriers.


Assuntos
Bactérias Anaeróbias/metabolismo , Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Nitritos/metabolismo , Poluentes Químicos da Água/metabolismo , Purificação da Água/instrumentação , Amônia , Desnitrificação , Desenho de Equipamento , Análise de Falha de Equipamento , Poluentes Químicos da Água/isolamento & purificação
7.
ChemSusChem ; 8(5): 789-94, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25477296

RESUMO

Core-shell Fe3O4@silica magnetic nanoparticles functionalized with a strong base, triazabicyclodecene (TBD), were successfully synthesized for harvesting microalgae and for one-pot microalgae-to-fatty acid methyl ester (FAME, or so-called biodiesel) conversion. Three types of algae oil sources (i.e., dried algae, algae oil, and algae concentrate) were used and the reaction conditions were optimized to achieve the maximum biodiesel yield. The results obtained in this study show that our TBD-functionalized Fe3O4@silica nanoparticles could effectively convert algae oil to biodiesel with a maximum yield of 97.1 %. Additionally, TBD-Fe3O4@silica nanoparticles act as an efficient algae harvester because of their adsorption and magnetic properties. The method presented in this study demonstrates the wide scope for the use of covalently functionalized core-shell nanoparticles for the production of liquid transportation fuels from algal biomass.


Assuntos
Biocombustíveis/microbiologia , Compostos Férricos/química , Microalgas/química , Nanopartículas/química , Dióxido de Silício/química , Biomassa , Catálise
8.
J Hazard Mater ; 277: 20-6, 2014 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-24268536

RESUMO

Hydroxyapatite nanoparticles (HAP NPs) are one of the widely used biocompatible materials. However, information about the reaction between HAP NPs and microorganisms is insufficient. This paper aims to understand the antibacterial property of a new nanocomposite consisting of gold-coated HAP and alginate polymer (namely, Au-HAP@Alg NPs). To the best of our knowledge, we reported the first information regarding to MIC (25mg/mL), DIZ (no visible zone), and IC50 (0.5mg/mL) of Au-HAP@Alg NPs toward the microorganism Escherichia coli TOP10. The real-time gene expression levels of polA, polB, cyd, mdoG, GAPDH, and 16S rRNA were maintained at stable levels up until conditions of 2.5mg/mL Au-HAP@Alg NPs. The results showed that 16S rRNA can be a good reference under these conditions. The expressions of GAPDH, cyd, and mdoG were inhibited obviously under condition of 10mg/mL of Au-HAP@Alg NPs. Our results indicated that the possible antibacterial mechanism of Au-HAP@Alg was through the interaction with these carbohydrate and cell wall-related genes. This novel biocompatible and antibacterial material can potentially be applied in medical and environmental fields.


Assuntos
Alginatos/química , Antibacterianos , Escherichia coli/efeitos dos fármacos , Ouro/química , Hidroxiapatitas , Nanocompostos/química , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/genética , Genes Bacterianos/efeitos dos fármacos , Hidroxiapatitas/química , Hidroxiapatitas/farmacologia , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Plasmídeos , RNA Ribossômico 16S/genética , Transcriptoma/efeitos dos fármacos
9.
Appl Microbiol Biotechnol ; 97(24): 10521-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24177731

RESUMO

Two 16S rRNA gene-based PCR primer sets (Brod541F/Amx820R and A438f/A684r) for detecting anammox bacteria were compared using sediments from Mai Po wetlands (MP), the South China Sea (SCS), a freshwater reservoir (R2), and sludge granules from a wastewater treatment plant (A2). By comparing their ability in profiling anammox bacteria, the recovered diversity, community structure, and abundance of anammox bacteria among all these diverse samples indicated that A438f/A684r performed better than Brod541F/Amx820R in retrieving anammox bacteria from these different environmental samples. Five Scalindua subclusters (zhenghei-I, SCS-I, SCS-III, arabica, and brodae) dominated in SCS whereas two Scalindua subclusters (zhenghei-II and wagneri) and one cluster of Kuenenia dominated in MP. R2 showed a higher diversity of anammox bacteria with two new retrieved clusters (R2-New-1 and R2-New-2), which deserves further detailed study. The dominance of Brocadia in sample A2 was supported by both of the primer sets used. Results collectively indicate strongly niche-specific community structures of anammox bacteria in different environments, and A438f/A684r is highly recommended for screening anammox bacteria from various environments when dealing with a collection of samples with diverse physiochemical characteristics.


Assuntos
Compostos de Amônio/metabolismo , Bactérias/isolamento & purificação , Biota , Primers do DNA/genética , Microbiologia Ambiental , Metagenômica/métodos , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , China , Análise por Conglomerados , Dados de Sequência Molecular , Oxirredução , RNA Bacteriano/genética , Análise de Sequência de DNA , Áreas Alagadas
10.
Bioresour Technol ; 147: 649-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24011603

RESUMO

Microbial communities and their kinetic performance in a single-stage autotrophic nitrogen-removal filter at an optimal oxygen supply were examined to determine the presence and activity of denitrifiers, anaerobic ammonia-oxidizing (anammox), ammonia-oxidizing, and nitrite-oxidizing bacteria. To this end, different molecular biology techniques such as real-time quantitative polymerase chain reaction (qPCR) and biomarkers such as 16S rRNA revealed a diverse microbial community along the filter. It was important to survey the specific species of anammox bacteria using a newly designed Candidatus Brocadiafulgida (BF) specific primer, as well as Candidatus Brocadia anammoxidans (BA) and Candidatus Kuenenia stuttgartiensis (KS) specific primers. An unexpected finding was that the predominant anammox species switched from KS in concentrated wastewater to BA in dilute wastewaters. The Eckenfelder model of the NH3-N transformation along the filter was Se=S0 exp(-0.192D/L(2.3217)). These results provide a foundational understanding of the microbial structure and reaction kinetics in such systems.


Assuntos
Consórcios Microbianos , Nitrogênio/isolamento & purificação , Oxigênio/química , Águas Residuárias/química , Microbiologia da Água , Cinética , Filogenia , RNA Ribossômico 16S/genética
11.
Chemistry ; 19(33): 10958-64, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-23813582

RESUMO

Ordered mesoporous alumina-doped titania thin films with anatase crystalline structure were prepared by using triblock copolymer Pluronic P123 as structure-directing agent. Uniform Al doping was realized by using aluminum isopropoxide as a dopant source which can be hydrolyzed together with titanium tetraisopropoxide. Aluminum doping into the titania framework can prevent rapid crystallization to the anatase phase, thereby drastically increasing thermal stability. With increasing Al content, the crystallization temperatures tend to increase gradually. Even when the Al content doped into the framework was increased to 15 mol %, a well-ordered mesoporous structure was obtained, and the mesostructural ordering was still maintained after calcination at 550 °C. During the calcination process, large uniaxial shrinkage occurred along the direction perpendicular to the substrate with retention of the horizontal mesoscale periodicity, whereby vertically oriented nanopillars were formed in the film. The resulting vertical porosity was successfully exploited to fabricate a high-speed and high-quality passive-matrix electrochromic display by using a leuco dye. The vertical nanospace in the films can effectively prevent drifting of the leuco dye.


Assuntos
Óxido de Alumínio/química , Titânio/química , Corantes/química , Cristalização , Técnicas Eletroquímicas , Eletrodos , Temperatura Alta , Poloxaleno/química , Porosidade , Espalhamento a Baixo Ângulo , Difração de Raios X
12.
J Nanosci Nanotechnol ; 13(3): 2117-21, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755654

RESUMO

Pure cultures of Botryococcus sp. microalgae have great potential for generating huge amounts of algae lipid that can be further converted into biodiesel. Lipids with nanometer in size can be applied to medicine and pharmacy recently. In this study, the effects of light intensity and CO2 concentration on the biomass productivity, lipid content, and lipid productivity of Botryococcus braunii were examined in 21-day intervals. The optimum cultivating conditions for biomass accumulation were 6,000 lux with 0.04% CO2 and 21 days of culturing; this provided the highest biomass productivity of 140.46 mg L(-1) d(-1). The highest lipid productivity of 44.46 mg L(-1) d(-1) occurred at 6,000 lux with 5% CO2 and 21 days of culturing. The maximum specific growth rate (micro(max)) was similar among different concentrations of CO2 (0.682 d(-1) under 12,000 lux at 10% CO2; 0.585 d(-1) under 6,000 lux at 5% CO2). Culturing at 5% or 10% CO2 has been shown to enhance the accumulation of lipids, introducing the possibility of using flue gas as a carbon source. The nanotechnology in this study will be helpful towards research in green science and engineering such as bio-fixation of CO2 and drug delivery systems.


Assuntos
Biomassa , Lipídeos/biossíntese , Microalgas/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Luz , Microalgas/metabolismo
13.
Water Res ; 47(9): 2929-37, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23548564

RESUMO

Completely autotrophic nitrogen removal over nitrite (CANON) process was employed in an 18 L sequencing batch reactor (SBR) for treatment of optoelectronic industrial wastewater containing high strength ammonium nitrogen (3712 ± 120 mg NH4(+) - N L(-1)). About 89% of total nitrogen and 98% of NH4(+) - N removal efficiencies were observed at the loading rate of 909 g N m(-3) d(-1) and the HRT of 4 d. A profound variation in the performance of CANON process was experienced at high DO exposure (above 1 mg L(-1)) and high nitrite concentration (above 100 mg L(-1)). Inhibition due to high DO exposure was found to be reversible phenomenon whereas the synergistic inhibition of nitrite, free ammonia and free nitrous acid was irreversible. The fluctuation of reactor temperature between 17 and 37 °C did not affect the performance of CANON system. The CANON process was stably controlled at high nitrogen loading rate for more than one month. The co-existence of aerobic and anaerobic ammonium oxidizing bacteria in the reactor was detected by The PCR analysis. About 5 fold increase in amount of anammox bacteria over a period of 258 days was confirmed from the results of qPCR on day 487.


Assuntos
Amônia/metabolismo , Eletrônica/métodos , Resíduos Industriais/análise , Nitrificação , Óptica e Fotônica/métodos , Águas Residuárias/química , Purificação da Água/métodos , Álcalis/análise , Anaerobiose , Processos Autotróficos , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Concentração de Íons de Hidrogênio , Nitratos/análise , Nitritos/análise , Nitrogênio/isolamento & purificação , Ácido Nitroso/análise , Oxirredução , Oxigênio/análise , Reação em Cadeia da Polimerase , Temperatura Ambiente , Fatores de Tempo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/isolamento & purificação
14.
Arch Environ Occup Health ; 68(2): 95-100, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23428059

RESUMO

Circulation or air conditioning (AC) system was proven to improve the air quality inside the vehicles; however, the quantified study was limited. In this study, fungal concentration under various driving mode inside the vehicle was proposed. The driving conditions were classified into 4 states: (1) window closed without AC and circulation, (2) window open without AC and circulation, (3) window closed with only circulation on, and (4) window closed with only AC on. Results show that at state 4, the mean respirable fraction was 83.3%, with a number median diameter of the fungi being 1.73 µm. More attention should be paid for these smaller fungi easily penetrating into the alveoli and probably lead to allergic alveolitis. Turning on AC for reducing the normalized concentration for each size range of fungi was suggested; however, the respirable fraction increased. Those who are prone to allergies or asthma are suggested to switch between AC and the circulation mode while driving a long time.


Assuntos
Ar Condicionado , Microbiologia do Ar , Poluição do Ar/análise , Exposição Ambiental , Fungos/isolamento & purificação , Veículos Automotores , Aerossóis/análise , Poluição do Ar/prevenção & controle , Automóveis , Contagem de Colônia Microbiana , Monitoramento Ambiental , Tamanho da Partícula , Taiwan
15.
Bioresour Technol ; 123: 400-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22940348

RESUMO

Autotrophic nitrogen removal via ammonia oxidizing (AOB) and anaerobic ammonium oxidizing (anammox) bacteria was evaluated for treatment of a dilute 50mg/L ammonia-containing solution in a single-stage nitrogen-removal filter at 25°C. Important was an external oxygenation system that permitted close control and measurement of oxygen supply, a difficulty with the generally used diffused air systems. Hydraulic retention time (HRT) was reduced in steps from 15 to 1h. At 1h HRT, total nitrogen (TN) removals varied between 73% and 94%, the maximum being obtained with a benchmark oxygenation ratio of 0.75mol O(2)/mol ammonia fed. At higher ratios, nitrate was formed causing TN removal efficiency to decrease. With lower ratios, TN and ammonia removals decreased in proportion to the decrease in BOR. When operating at or below the BOR, nitrate formation equaled no more than 2% of the ammonia removed, a value much less than has previously been reported.


Assuntos
Processos Autotróficos , Nitrogênio/isolamento & purificação , Oxigênio/química , Águas Residuárias/química , Purificação da Água/métodos , Aclimatação , Amônia/isolamento & purificação , Bactérias/metabolismo , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Biotransformação , Cinética , Termodinâmica , Fatores de Tempo , Purificação da Água/instrumentação
16.
J Nanosci Nanotechnol ; 12(6): 4502-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905492

RESUMO

In this research paper, we synthesize various types of mesoporous titania nanoparticles (MTNs) with suitable surface area and pore size while creating anatase frameworks by applying hydrothermal treatment or calcination at different temperatures. Wide-angle XRD patterns and N2 adsorption-desorption isotherms reveal that the MTNs with crystallized anatase frameworks can be synthesized after an optimized hydrothermal treatment. In contrast, calcination of MTNs at high temperature caused the collapse of mesoporous structure, resulted in drastic reduction of the surface area of the MTNs. In addition, we investigate the photocatalytic activity of the prepared MTNs by measuring the degradation of methylene blue (MB). The results show that the reaction rates of the photocatalytic MB decomposition strongly depend on the degree of crystallinity in the MTNs frameworks and on the surface area of MTNs.


Assuntos
Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Titânio/química , Catálise , Luz , Substâncias Macromoleculares/química , Substâncias Macromoleculares/efeitos da radiação , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/efeitos da radiação , Nanotecnologia/métodos , Tamanho da Partícula , Fotoquímica/métodos , Porosidade , Propriedades de Superfície/efeitos da radiação
17.
J Formos Med Assoc ; 111(5): 275-83, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22656398

RESUMO

BACKGROUND/PURPOSE: Umbilical cord blood is rich in primitive natural killer (NK) cells, which are activated by interleukin (IL)-12. It was previously reported that a novel IL-12 family cytokine, IL-27 comprised of EBI3 and p28, was elevated in maternal serum during normal pregnancy. Thus, we compared the immune regulatory functions of IL-27 and IL-12 on mononuclear cells derived from cord blood and adult peripheral blood. METHODS: After stimulation with IL-27, IL-12, and IL-27 combined with IL-12, the cytotoxicity against BJAB lymphoma cells by blood mononuclear cells was performed. Then immunofluorescence staining, reverse transcriptase-polymerase chain reaction and Western blotting were used to detect the effects of IL-27 and IL-12 in isolated NK cells. RESULTS: IL-27, IL-12, and IL-27 combined with IL-12 enhanced the cytotoxicity of adult peripheral blood cells and cord blood cells, but the proliferation of distinct subpopulations of cells was not evident. Similar results were also obtained with purified cord blood NK cells. Interestingly, distinct from IL-12, IL-27 could induce aggregation and morphological changes of umbilical cord blood cells. Finally, IL-27 combined with IL-12 could stimulate increased IL-27 receptor (gp130 and WSX-1) transcripts in purified cord blood NK cells. However, the activation of signal transducer and activator of transcription 3 (STAT3) in NK cells was only detected in the presence of IL-27, but not IL-12 alone. CONCLUSION: From previous results, we summarize our current understanding of the augmentation of distinct regulation of NK cells by IL-27 and IL-12.


Assuntos
Sangue Fetal/imunologia , Interleucina-12/imunologia , Interleucinas/imunologia , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Fator de Transcrição STAT3/metabolismo , Biomarcadores/metabolismo , Western Blotting , Linhagem Celular Tumoral , Testes Imunológicos de Citotoxicidade , Citotoxicidade Imunológica , Humanos , Interleucina-12/metabolismo , Interleucinas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
J Microbiol Biotechnol ; 22(8): 1141-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22713992

RESUMO

Polyhydroxyalkanoate (PHA) is a class of biodegradable plastics that have great potential applications in the near future. In this study, the micro-biodiversity and productivity of PHA-accumulating bacteria in activated sludge from a domestic wastewater treatment plant were investigated. A previously reported primer set and a selfdesigned primer set (phaCF1BO/phaCR2BO) were both used to amplify the PHA synthase (phaC) gene of isolated colonies. The new primers demonstrated higher sensitivity for phaC, and combining the PCR results of the two primer sets was able to widen the range of detected genera and raise the sensitivity to nearly 90%. Results showed that 85.3% of the identified bacteria were Gram-negative, with Ralstonia as the dominant genus, and 14.7% were Gram-positive. In addition, Zoogloea and Rhizobium contained the highest amounts of intracellular PHA. It is apparent that glucose was a better carbon source than pentone or tryptone for promoting PHA production in Micrococcus. Two different classes, class I and class II, of phaC were detected from alphaproteobacteria, betaproteobacteria, and gammaproteobacteria, indicating the wide diversity of PHA-accumulating bacteria in this particular sampling site. Simultaneous wastewater treatment and PHA production is promising by adopting the high PHAaccumulating bacteria isolated from activated sludge.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Técnicas Bacteriológicas/métodos , Biodiversidade , Poli-Hidroxialcanoatos/metabolismo , Reação em Cadeia da Polimerase/métodos , Esgotos/microbiologia , Aciltransferases/genética , Bactérias/genética , Bactérias/isolamento & purificação , Primers do DNA/genética
19.
Bioresour Technol ; 113: 225-31, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22237171

RESUMO

Simultaneous partial nitrification, anaerobic ammonium oxidation and denitrification (SNAD) system was applied to treat the opto-electronic industrial wastewater in a 2.5L sequencing batch reactor. The characteristics of wastewater were low C/N ratio (≈ 0.2) with 100mg-COD/L and 567 mg NH(4)(+)-N/L. The experiment was carried out over 8 months in six different stages, where nitrogen loading rate was gradually increased from 16 g-N/m(3)d in stage I to 230 g-N/m(3)d in stage VI. The COD and nitrogen removal rates by the SNAD system reached to 28 g COD/m(3)d and 197 g NH(4)(+)-N/m(3)d, respectively in stage VI. These results showed that the SNAD system is suitable to treat wastewater containing high nitrogen pollutants with low COD level. Presence of ammonium oxidizing bacteria and anammox bacteria were confirmed by polymerase chain reaction (PCR). PCR results also indicated that Candidatus Kuenenia stuttgartiensis may be one of the dominant species in the reactor.


Assuntos
Nitrogênio/isolamento & purificação , Compostos de Amônio Quaternário/química , Anaerobiose , Eletroforese em Gel de Ágar , Nitrificação , Oxirredução , Reação em Cadeia da Polimerase , Esgotos
20.
Int J Mol Sci ; 12(6): 3888-927, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21747714

RESUMO

Nanotechnology offers outstanding potential for future biomedical applications. In particular, due to their unique characteristics, hybrid nanomaterials have recently been investigated as promising platforms for imaging and therapeutic applications. This class of nanoparticles can not only retain valuable features of both inorganic and organic moieties, but also provides the ability to systematically modify the properties of the hybrid material through the combination of functional elements. Moreover, the conjugation of targeting moieties on the surface of these nanomaterials gives them specific targeted imaging and therapeutic properties. In this review, we summarize the recent reports in the synthesis of hybrid nanomaterials and their applications in biomedical areas. Their applications as imaging and therapeutic agents in vivo will be highlighted.


Assuntos
Compostos Inorgânicos/química , Nanoestruturas/química , Compostos Orgânicos/química , Animais , Meios de Contraste/química , Meios de Contraste/farmacocinética , Humanos , Metais/química , Nanomedicina , Neoplasias/diagnóstico , Distribuição Tecidual
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