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1.
Database (Oxford) ; 20192019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31609452

RESUMO

Dynamic development of biobanking industry (both business and science) resulted in an increased number of IT systems for samples and data management. The most difficult and complicated case for the biobanking community was cooperation between institutions, equipped with different IT systems, in the field of scientific research, mainly data interchange and information flow. Tools available on the market relate mainly to the biobank or collection level. Efficient and universal protocols including the detailed information about the donor and the sample are still very limited. Here, we have developed BioSCOOP, a communication protocol in the form of a well documented JSON API. The main aim of this study was to harmonize and standardize the rules of communication between biobanks on the level of information about the donor together with information about the sample. The purpose was to create a communication protocol for two applications: to transfer the information between different biobanks and to allow the searching and presentation of the sample and data sets.


Assuntos
Bancos de Espécimes Biológicos , Disseminação de Informação , Humanos
2.
Mater Sci Eng C Mater Biol Appl ; 70(Pt 1): 471-478, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27770918

RESUMO

The present paper concerns the potential use of montmorillonite as a drug carrier and focusses on the intercalation of the studied clay with gentamicin (an aminoglycoside antibiotic) at various temperatures (20, 50 and 80°C). The experiments were performed to identify the temperature required for the optimum intercalation of gentamicin into the interlayer of montmorillonite. The structural and microstructural properties of gentamicin and the potential for introducing it between smectite clay layers were investigated by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopic techniques, and SEM with EDS analysis. Additionally, the in vitro drug release behaviour of the montmorillonite-gentamicin complex and its antibacterial activity against Escherichia coli (E. coli) bacteria was investigated. Based on these studies, the impact of temperature on the intercalation of the drug between layers of smectite was evaluated. It was found that an intercalation temperature of 50°C resulted in the highest shift in the position of principle peak d(001) as measured by XRD, suggesting, that the greatest amount of gentamicin had been introduced into the interlayer space of montmorillonite at this temperature. Subsequently, the montmorillonite-gentamicin complex material obtained at 50°C revealed the greatest capacity for killing E. coli bacteria during an in vitro test.


Assuntos
Antibacterianos/farmacologia , Bentonita/química , Liberação Controlada de Fármacos , Gentamicinas/farmacologia , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Lett Appl Microbiol ; 58(6): 556-63, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24494800

RESUMO

UNLABELLED: This is the first reported study on the immobilization of living recombinant Escherichia coli cells that overexpress cyclopentanone monooxygenase in polyvinyl alcohol gel particles LentiKats®. Immobilized cells overexpressing cyclopentanone monooxygenase have been used as a model of biocatalyst for enantioselective Baeyer-Villiger biooxidation of rac-bicyclo[3.2.0]hept-2-en-6-one into regioisomeric lactones. This process is useful for the syntheses of cytostatic sarkomycin, several prostaglandins and other biologically active compounds. The original technique for qualitative analysis of enzyme expression within free cells and cells entrapped in LentiKats® using SDS-PAGE was developed and used for verification of optimal conditions for the induction of cyclopentanone monooxygenase. Here, we successfully performed six repeated batch Baeyer-Villiger biooxidations utilizing entrapped cells using 40% (w/v) polyvinyl alcohol gel particles in flasks with baffles. The latter conditions have been found to be the most appropriate achieving optimal oxygen transfer within LentiKats®. Moreover, immobilized cells retained their catalytic efficiency over six reaction cycles, while the catalytic efficiency of free cells decreased after three reaction cycles. SIGNIFICANCE AND IMPACT OF THE STUDY: Immobilization in polyvinylalcohol gel particles is desirable technique with presumptive impact on industrial applications of recombinant whole-cell Baeyer-Villiger monooxygenases as biocatalysts for production of bioactive compounds and precursors of potentially new drugs. An original immobilization of cells E. coli with overproduced Baeyer-Villiger monooxygenase improved their stability in repetitive batch biooxidations as compared to free cells. Detected autoinduction of recombinant enzyme in pET22b+ plays significant role in application of immobilized cells as it may increase specific activity of cells in repetitive use under growing reaction conditions. Original technique for qualitative analysis of enzyme expression within immobilized cells was developed.


Assuntos
Proteínas de Bactérias/biossíntese , Escherichia coli/metabolismo , Oxigenases/biossíntese , Álcool de Polivinil/química , Proteínas de Bactérias/química , Biocatálise , Reatores Biológicos , Células Imobilizadas/enzimologia , Comamonas/enzimologia , Meios de Cultura , Géis , Lactonas , Oxirredução , Oxigênio/química , Oxigenases/química , Transformação Bacteriana
4.
J Tissue Eng Regen Med ; 8(11): 906-18, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23038649

RESUMO

Interest is growing in the use of hydrogels as bone tissue-engineering (TE) scaffolds due to advantages such as injectability and ease of incorporation of active substances such as enzymes. Hydrogels consisting of gellan gum (GG), an inexpensive calcium-crosslinkable polysaccharide, have been applied in cartilage TE. To improve GG suitability as a material for bone TE, alkaline phosphatase (ALP), an enzyme involved in mineralization of bone by cleaving phosphate from organic phosphate, was incorporated into GG hydrogels to induce mineralization with calcium phosphate (CaP). Incorporated ALP induced formation of apatite-like material on the submicron scale within GG gels, as shown by FTIR, SEM, EDS, XRD, ICP-OES, TGA and von Kossa staining. Increasing ALP concentration increased amounts of CaP as well as stiffness. Mineralized GG was able to withstand sterilization by autoclaving, although stiffness decreased. In addition, mineralizability and stiffness of GG was enhanced by the incorporation of polydopamine (PDA). Furthermore, mineralization of GG led to enhanced attachment and vitality of cells in vitro while cytocompatibility of the mineralized gels was comparable to one of the most commonly used bone substitute materials. The results proved that ALP-mediated enzymatic mineralization of GG could be enhanced by functionalization with PDA.


Assuntos
Osso e Ossos/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Indóis/farmacologia , Polímeros/farmacologia , Polissacarídeos Bacterianos/farmacologia , Engenharia Tecidual/métodos , Fosfatase Alcalina/metabolismo , Osso e Ossos/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Módulo de Elasticidade/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Liofilização , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Indóis/química , Masculino , Microscopia Eletrônica de Varredura , Peso Molecular , Polímeros/química , Espectrometria por Raios X , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Difração de Raios X
5.
J Mater Sci Mater Med ; 24(12): 2761-73, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23912792

RESUMO

In the quest for improved bone growth and attachment around dental implants, chemical surface modifications are one possibility for future developments. The biological properties of titanium based materials can be further enhanced with methods like anodic polarization to produce an active rather than a passive titanium oxide surface. Here we investigate the formation of hydroxide groups on sand blasted and acid etched titanium and titanium-zirconium alloy surfaces after anodic polarization in an alkaline solution. X-ray photoelectron spectroscopy shows that the activated surfaces had increased reactivity. Furthermore the activated surfaces show up to threefold increase in OH(-) concentration in comparison to the original surface. The surface parameters Sa, Sku, Sdr and Ssk were more closely correlated to time and current density for titanium than for titanium-zirconium. Studies with MC3T3-E1 osteoblastic cells showed that OH(-) activated surfaces increased mRNA levels of osteocalcin and collagen-I.


Assuntos
Oxigênio/química , Titânio/química , Células 3T3 , Animais , Materiais Biocompatíveis/química , Diferenciação Celular , Proliferação de Células , Colágeno Tipo I/metabolismo , Implantes Dentários , Radical Hidroxila , Camundongos , Osteoblastos/citologia , Osteocalcina/metabolismo , Espectroscopia Fotoeletrônica , Propriedades de Superfície
6.
FEBS Lett ; 498(1): 46-51, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11389896

RESUMO

Surf1p is a protein involved in the assembly of mitochondrial respiratory chain complexes. However its exact role in this process remains to be elucidated. We studied SHY1, the yeast homologue of SURF1, with an aim to obtain a better understanding of the molecular pathogenesis of cytochrome c oxidase (COX) deficiency in SURF1 mutant cells from Leigh syndrome patients. Assembly of COX was analysed in a shy1 null mutant strain by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Steady-state levels of the enzyme were found to be strongly reduced, the total amount of assembled complex being approximately 30% of control. The presence of a significant amount of holo-COX in the SHY1-disruptant strain suggests that Shy1p may either facilitate assembly of the enzyme, or increase its stability. However, our observations, based on 2D-PAGE analysis of mitochondria labelled in vitro, now provide the first direct evidence that COX assembly is impaired in a Deltashy1 strain. COX enzyme assembled in the absence of Shy1p appears to be structurally and enzymically normal. The in vitro labelling studies additionally indicate that mitochondrial translation is significantly increased in the shy1 null mutant strain, possibly reflecting a compensatory mechanism for reduced respiratory capacity. Protein interactions of both Shy1p and Surf1p are implied by their appearance in a high molecular weight complex of about 250 kDa, as shown by 2D-PAGE.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Eletroforese em Gel Bidimensional , Proteínas Mitocondriais , Peso Molecular , Proteínas/metabolismo , Saccharomyces cerevisiae/enzimologia
7.
Virology ; 140(2): 360-3, 1985 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-2982237

RESUMO

Three new phage-like particles (CG1, CG2, and CGK1) were isolated from Corynebacterium glutamicum CBII. Particles CG1 and CG2 are DNA phages with long, noncontractile tails, CGK1 is a killer particle according to electron microscopy. A heat-stable low-molecular-weight bacteriocidal substance affecting various coryneform bacteria was observed to be joined to the killer particle CGK1.


Assuntos
Bacteriófagos/isolamento & purificação , Corynebacterium , Bacteriocinas/isolamento & purificação , Bacteriófagos/ultraestrutura , Corynebacterium/ultraestrutura , Enzimas de Restrição do DNA , DNA Viral/isolamento & purificação , Mitomicina , Mitomicinas/farmacologia , Ativação Viral/efeitos dos fármacos
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