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1.
Trends Biochem Sci ; 43(4): 230-232, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29550243

RESUMO

Affimer proteins can bind to a wide variety of target molecules. They can complement and represent a promising alternative to conventional antibodies as they can target molecules with high affinity, specificity, and stability. In addition, they can be selected and expressed in bacterial and mammalian systems. Affimer protein technology shows promise as a tool in the biologist's arsenal of the future in imaging, diagnostic, and therapeutic applications.


Assuntos
Proteínas , Nanomedicina Teranóstica , Animais
2.
Rheumatology (Oxford) ; 60(4): 1588-1592, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33097948

RESUMO

The aim of this guideline is to provide an update on evidence-based recommendations for treatment of adult patients with PsA. The previous BSR guidelines for PsA were published in 2012 and since that time, there have been many new advanced therapies licensed for PsA. This update will provide practical guidance for clinicians on the optimal selection of advanced therapies taking into account different domains of PsA (arthritis, enthesitis, dactylitis, axial disease and psoriasis) and key associated comorbidities. It will also update guidance on treatment strategy including the use of a treat-to-target approach. The guideline will be developed using the methods and processes outlined in Creating Clinical Guidelines: Our Protocol. (1) This development process to produce guidance, advice and recommendations for practice has National Institute for Health and Care Excellence (NICE) accreditation.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Psoriásica/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Humanos , Reumatologia/normas , Resultado do Tratamento
5.
Rheumatol Adv Pract ; 8(3): rkae077, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006537

RESUMO

This guideline will provide up-to-date, evidence-based recommendations on the safe use of non-biologic DMARDs, also called conventional synthetic DMARDs (csDMARD), across the full spectrum of autoimmune rheumatic diseases. The guideline will update the guideline published in 2017 and will be expanded to include people of all ages. Updated information on the monitoring of DMARDs and vaccinations will be included. The guideline will be developed using the methods and processes described in the British Society for Rheumatology's 'Creating clinical guidelines: our protocol', updated 2023.

6.
Microb Cell Fact ; 11: 28, 2012 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-22376274

RESUMO

BACKGROUND: Lunasin is a chemopreventive peptide produced in a number of plant species. It comprises a helical region with homology to a region of chromatin binding proteins, an Arg-Gly-Asp cell adhesion motif and eight aspartic acid residues. In vitro studies indicate that lunasin suppresses chemical and oncogene driven transformation of mammalian cells. We have explored efficient recombinant production of lunasin by exploiting the Clostridium thermocellum CipB cellulose binding domain (CBD) as a fusion partner protein. RESULTS: We used a pET28 vector to express a CBD-lunasin fusion with a hexahistidine tag and Tobacco Etch Virus protease site, to allow protease-mediated release of native lunasin. Autoinduction in E. coli BL21 (DE3) Star cells achieved expression of 3.35 g/L of CBD-lunasin fusion protein. The final yield of lunasin was 210 mg/L corresponding to 32% of the theoretical yield. Purification by cellulose binding and nickel affinity chromatography were tested with the latter proving more satisfactory.The effects of CBD-lunasin expression on growth and morphology of the E. coli cells were examined by light and electron microscopy revealing an altered morphology in a proportion of cells. Cell division appeared to be inhibited in these cells resulting in elongated, non-septated cells. CONCLUSIONS: The use of CBD as a fusion partner gave high protein yields by autoinduction, with lunasin release by TEV protease cleavage. With some optimisation this approach could provide a potentially valuable route for production of this therapeutic peptide. Over-expression in the host cells manifest as a cell division defect in a population of the cells, presumably mimicking some aspect of the chemopreventive function observed in mammalian cells.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Proteínas de Bactérias/genética , Cromatografia de Afinidade , Clostridium thermocellum/metabolismo , Endopeptidases/metabolismo , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Histidina/biossíntese , Histidina/genética , Oligopeptídeos/biossíntese , Oligopeptídeos/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação
7.
Microb Cell Fact ; 11: 92, 2012 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-22759375

RESUMO

BACKGROUND: Self-assembling peptides that form nanostructured hydrogels are important biomaterials for tissue engineering scaffolds. The P11-family of peptides includes, P11-4 (QQRFEWEFEQQ) and the complementary peptides P11-13 (EQEFEWEFEQE) and P11-14 (QQOrnFOrnWOrnFOrnQQ). These form self-supporting hydrogels under physiological conditions (pH 7.4, 140 mM NaCl) either alone (P11-4) or when mixed (P11-13 and P11-14). We report a SUMO-peptide expression strategy suitable for allowing release of native sequence peptide by SUMO protease cleavage. RESULTS: We have expressed SUMO-peptide fusion proteins from pET vectors by using autoinduction methods. Immobilised metal affinity chromatography was used to purify the fusion protein, followed by SUMO protease cleavage in water to release the peptides, which were recovered by reverse phase HPLC. The peptide samples were analysed by electrospray mass spectrometry and self-assembly was followed by circular dichroism and transmission electron microscopy. CONCLUSIONS: The fusion proteins were produced in high yields and the ß-structured peptides were efficiently released by SUMO protease resulting in peptides with no additional amino acid residues and with recoveries of 46% to 99%. The peptides behaved essentially the same as chemically synthesised and previously characterised recombinant peptides in self-assembly and biophysical assays.


Assuntos
Peptídeos/química , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sequência de Aminoácidos , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Escherichia coli/metabolismo , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Peptídeos/genética , Peptídeos/metabolismo , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Espectrometria de Massas por Ionização por Electrospray
8.
Biofabrication ; 11(4): 045006, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-30743252

RESUMO

BACKGROUND: One of the main challenges for extrusion 3D bioprinting is the identification of non-synthetic bioinks with suitable rheological properties and biocompatibility. Our aim was to optimize and compare the printability of crystal, fibril and blend formulations of novel pulp derived nanocellulose bioinks and assess biocompatibility with human nasoseptal chondrocytes. METHODS: The printability of crystalline, fibrillated and blend formulations of nanocellulose was determined by assessing resolution (grid-line assay), post-printing shape fidelity and rheology (elasticity, viscosity and shear thinning characteristics) and compared these to pure alginate bioinks. The optimized nanocellulose-alginate bioink was bioprinted with human nasoseptal chondrocytes to determine cytotoxicity, metabolic activity and bioprinted construct topography. RESULTS: All nanocellulose-alginate bioink combinations demonstrated a high degree of shear thinning with reversible stress softening behavior which contributed to post-printing shape fidelity. The unique blend of crystal and fibril nanocellulose bioink exhibited nano- as well as micro-roughness for cellular survival and differentiation, as well as maintaining the most stable construct volume in culture. Human nasoseptal chondrocytes demonstrated high metabolic activity post printing and adopted a rounded chondrogenic phenotype after prolonged culture. CONCLUSIONS: This study highlights the favorable rheological, swelling and biocompatibility properties of nanocellulose-alginate bioinks for extrusion-based bioprinting.


Assuntos
Alginatos/química , Bioimpressão , Celulose/química , Tinta , Nanopartículas/química , Impressão Tridimensional , Madeira/química , Biomassa , Sobrevivência Celular , Celulose/ultraestrutura , Condrócitos/citologia , Condrócitos/metabolismo , Reagentes de Ligações Cruzadas/química , Humanos , L-Lactato Desidrogenase/metabolismo , Nanopartículas/ultraestrutura , Septo Nasal/citologia , Reologia , Estresse Mecânico , Viscosidade
10.
Trends Biotechnol ; 36(4): 340-341, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29402473

RESUMO

Bacterial species are now being mixed with various bioinks to produce functional complex materials using 3D printing. These systems show enormous potential in applications such as bioremediation, sensors that can detect toxic chemicals, oil spill filters, and wound dressings. In particular, 3D-printed minibiofactories represent a potential paradigm shift in biotechnology.


Assuntos
Bactérias , Biotecnologia , Impressão Tridimensional , Alginatos , Biodegradação Ambiental , Curativos Biológicos , Hidrogel de Polietilenoglicol-Dimetacrilato , Engenharia Tecidual
12.
Rheumatol Adv Pract ; 2(2): rky042, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31431979

RESUMO

OBJECTIVE: Real-world evidence of the long-term effectiveness of TNF-α inhibitor (TNFi) therapy in patients with PsA is limited. This study was conducted to describe patterns of TNFi therapy and treatment responses in patients with PsA treated in UK clinical practice. METHODS: A multicentre, retrospective, observational cohort study of consenting patients treated with TNFi for PsA with ≥3 years follow-up from first TNFi initiation (observation period) was carried out in 11 UK National Health Service hospitals. Data were collected concerning baseline patient characteristics, PsA-related treatment pathways and TNFi treatment responses (PsA response criteria components: swollen/tender joint counts, physician and patient global assessments). RESULTS: The mean age of patients (n = 141) was 50.3 (s.d.: 12.1) years (50% male). During a median observation period of 4.5 (range: 3.4-5.5) years, patients received a median of one (range: one to five) TNFi. Twelve-week response rates for first TNFi (where available) were as follows: 80% (n = 64/80) for swollen joint counts, 79% (n = 63/79) for tender joint counts, 79% (n = 37/47) for physician global assessments, 69% (n = 41/59) for patient global assessments and 79% (n = 37/47) for PsA response criteria. At the end of the observation period, the proportions of patients remaining on first, second, third and fourth/fifth TNFi were 56, 15, 5 and 3%, respectively; 21% of patients permanently discontinued TNFi therapy. CONCLUSION: Long-term TNFi therapy is generally well tolerated and may be effective; however, after initial TNFi failure, there appears to be progressively less benefit and more adverse effects with successive TNFi switches. Strategies are needed for effective therapy for PsA beyond the first TNFi failure.

13.
Carbohydr Polym ; 198: 270-280, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30093000

RESUMO

Bioinspiration from hierarchical structures found in natural environments has heralded a new age of advanced functional materials. Nanocellulose has received significant attention due to the demand for high-performance materials with tailored mechanical, physical and biological properties. In this study, nanocellulose fibrils, nanocrystals and a novel mixture of fibrils and nanocrystals (blend) were prepared from softwood biomass using the AVAP® biorefinery technology. These materials were characterized using transmission and scanning electron microscopy, and atomic force microscopy. This analysis revealed a nano- and microarchitecture with extensive porosity. Notable differences included the nanocrystals exhibiting a compact packing of nanorods with reduced porosity. The NC blend exhibited porous fibrillar networks with interconnecting compact nanorods. Fourier transform infrared spectroscopy and X-ray diffraction confirmed a pure cellulose I structure. Thermal studies highlighted the excellent stability of all three NC materials with the nanocrystals having the highest decomposition temperature. Surface charge analysis revealed stable colloid suspensions. Rheological studies highlighted a dominance of elasticity in all variants, with the NC blend being more rigid than the NC fibrils and nanocrystals, indicating a double network hydrogel structure. Given these properties, it is thought that these materials show great potential in (bio)nanomaterial applications where careful control of microarchitecture, surface topography and porosity are required.

14.
Adv Healthc Mater ; 6(16)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28558161

RESUMO

Regenerative medicine has been highlighted as one of the UK's 8 'Great Technologies' with the potential to revolutionize patient care in the 21st Century. Over the last decade, the concept of '3D bioprinting' has emerged, which allows the precise deposition of cell laden bioinks with the aim of engineering complex, functional tissues. For 3D printing to be used clinically, there is the need to produce advanced functional biomaterials, a new generation of bioinks with suitable cell culture and high shape/print fidelity, to match or exceed the physical, chemical and biological properties of human tissue. With the rapid increase in knowledge associated with biomaterials, cell-scaffold interactions and the ability to biofunctionalize/decorate bioinks with cell recognition sequences, it is important to keep in mind the 'printability' of these novel materials. In this illustrated review, we define and refine the concept of 'printability' and review seminal and contemporary studies to highlight the current 'state of play' in the field with a focus on bioink composition and concentration, manipulation of nozzle parameters and rheological properties.


Assuntos
Materiais Biocompatíveis , Bioimpressão , Impressão Tridimensional , Medicina Regenerativa , Células Cultivadas , Humanos , Engenharia Tecidual , Alicerces Teciduais
15.
Adv Healthc Mater ; 3(11): 1703-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24692428

RESUMO

Over the years, nanotechnology has greatly developed, moving from careful design strategies and synthesis of novel nanostructures to producing them for specific medical and biological applications. The use of nanotechnology in diagnostics, drug delivery, and tissue engineering holds great promise for the treatment of stroke in the future. Nanoparticles are employed to monitor grafted cells upon implantation, or to enhance the imagery of the tissue, which is coupled with a noninvasive imaging modality such as magnetic resonance imaging, computed axial tomography or positron emission tomography scan. Contrast imaging agents used can range from iron oxide, perfluorocarbon, cerium oxide or platinum nanoparticles to quantum dots. The use of nanomaterial scaffolds for neuroregeneration is another area of nanomedicine, which involves the creation of an extracellular matrix mimic that not only serves as a structural support but promotes neuronal growth, inhibits glial differentiation, and controls hemostasis. Promisingly, carbon nanotubes can act as scaffolds for stem cell therapy and functionalizing these scaffolds may enhance their therapeutic potential for treatment of stroke. This Progress Report highlights the recent developments in nanotechnology for the detection and therapy of stroke. Recent advances in the use of nanomaterials as tissue engineering scaffolds for neuroregeneration will also be discussed.


Assuntos
Nanoestruturas/uso terapêutico , Nanotecnologia/métodos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Sistemas de Liberação de Medicamentos/métodos , Humanos , Nanopartículas/uso terapêutico , Engenharia Tecidual/métodos , Alicerces Teciduais
16.
Brain Pathol ; 22(5): 592-606, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22303870

RESUMO

Glioblastoma is the most common type of primary brain tumor in adults and is among the most lethal and least successfully treated solid tumors. Recently, research into the area of stem cells in brain tumors has gained momentum. However, due to the relatively new and novel hypothesis that a subpopulation of cancer cells in each malignancy has the potential for tumor initiation and repopulation, the data in this area of research are still in its infancy. This review article is aimed at attempting to bring together research carried out so far in order to build an understanding of glioblastoma stem cells (GSCs). Initially, we consider GSCs at a morphological and cellular level, and then discuss important cell markers, signaling pathways and genetics. Furthermore, we highlight the difficulties associated with what some of the evidence indicates and what collectively the studies contribute to further defining the interpretation of GSCs.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/patologia , Células-Tronco Neoplásicas/patologia , Humanos , Mutação/genética , Transdução de Sinais/genética
17.
Adv Healthc Mater ; 1(5): 640-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23184800

RESUMO

Rational molecular design of self- assembling peptide-based materials that spontaneously form self-supporting hydrogels shows potential in many healthcare applications. Binary peptides based on complementary charged sequences are developed, and the use of biophysical analysis and cell-based studies highlights that the charged interactions can influence the properties of peptide materials and ultimately affect biomaterial applications.


Assuntos
Materiais Biocompatíveis/química , Fibroblastos/citologia , Fibroblastos/fisiologia , Hidrogéis/química , Peptídeos/química , Alicerces Teciduais , Sítios de Ligação , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Ligação Proteica
18.
Biomaterials ; 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21723600

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

19.
Biomaterials ; 31(36): 9395-405, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20932572

RESUMO

Synthetic nanostructures based on self-assembling systems that aim to mimic natural extracellular matrix are now being used as substrates in tissue engineering applications. Peptides are excellent starting materials for the self-assembly process as they can be readily synthesised both chemically and biologically. P11-4 is an 11 amino acid peptide that undergoes triggered self-assembly to form a self-supporting hydrogel. It exists as unimers of random coil conformations in water above pH 7.5 but at low pH adopts an antiparallel ß-sheet conformation. It also self-assembles under physiological conditions in a concentration-dependent manner. Here we describe an unimer P11-4 production system and the use of a simple site-directed mutagenesis approach to generate a series of other P11-family peptide expression vectors. We have developed an efficient purification strategy for these peptide biomaterials using a simple procedure involving chemical cleavage with cyanogen bromide then repeated filtration, lyophilisation and wash steps. We report peptide-fusion protein yields of ca. 4.64 g/L and we believe the highest reported recovery of a recombinant self-assembling peptide at 203 mg/L of pure recombinant P11-4. This peptide forms a self-supporting hydrogel under physiological conditions with essentially identical physico-chemical properties to the chemically synthesised peptide. Critically it also displays excellent cytocompatibility when tested with primary human dermal fibroblasts. This study demonstrates that high levels of a series of recombinant self-assembling peptides can be purified using a simple process for applications as scaffolds in tissue engineering.


Assuntos
Materiais Biocompatíveis/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Engenharia Tecidual/métodos , Sequência de Aminoácidos , Materiais Biocompatíveis/química , Morte Celular/efeitos dos fármacos , Clonagem Molecular , Brometo de Cianogênio/metabolismo , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Humanos , Hidrogéis/farmacologia , Corpos de Inclusão/ultraestrutura , Espectrometria de Massas , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Solubilidade/efeitos dos fármacos
20.
Trends Biotechnol ; 27(7): 423-33, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19497631

RESUMO

Self-assembling peptide-based biomaterials are being developed for use as 3D tissue engineering scaffolds and for therapeutic drug-release applications. Chemical synthesis provides custom-made peptides in small quantities, but production approaches based upon transgenic organisms might be more cost-effective for large-scale peptide production. Long lead times for developing appropriate animal clones or plant lines and potential negative public opinion are obstacles to these routes. Microbes, particularly safe organisms used in the food industry, offer a more rapid route to the large-scale production of recombinant self-assembling biomaterials. In this review, recent advances and challenges in the recombinant production of collagen, elastin and de novo designed self-assembling peptides are discussed.


Assuntos
Materiais Biocompatíveis/metabolismo , Portadores de Fármacos/farmacologia , Engenharia Tecidual/métodos , Animais , Bactérias/metabolismo , Fungos/metabolismo , Organismos Geneticamente Modificados/metabolismo , Plantas
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