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1.
Clin Chem ; 65(8): 1006-1014, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31118187

RESUMO

OBJECTIVES: We sought to evaluate diagnostic accuracy of a high-sensitivity cardiac troponin I (hs-cTnI) assay for acute coronary syndromes (ACS) in the emergency department (ED). The assay has high precision at low concentrations and can detect cTnI in 96.8% of healthy individuals. METHODS: In successive prospective multicenter studies ("testing" and "validation"), we included ED patients with suspected ACS. We drew blood for hs-cTnI [Singulex Clarity® cTnI; 99th percentile, 8.67 ng/L; limit of detection (LoD), 0.08 ng/L] on arrival. Patients also underwent hs-cTnT (Roche Elecsys) testing over ≥3 h. The primary outcome was an adjudicated diagnosis of ACS, defined as acute myocardial infarction (AMI; prevalent or incident), death, or revascularization within 30 days. RESULTS: The testing and validation studies included 665 and 2470 patients, respectively, of which 94 (14.1%) and 565 (22.9%) had ACS. At a 1.5-ng/L cutoff, hs-cTnI had good sensitivity for AMI in both studies (98.7% and 98.1%, respectively) and would have "ruled out" 40.1% and 48.9% patients. However, sensitivity was lower for ACS (95.7% and 90.6%, respectively). At a 0.8-ng/L cutoff, sensitivity for ACS was higher (97.5% and 97.9%, ruling out 28.6% patients in each cohort). The hs-cTnT assay had similar performance at the LoD (24.6% ruled out; 97.2% sensitivity for ACS). CONCLUSIONS: The hs-cTnI assay could immediately rule out AMI in 40% of patients and ACS in >25%, with similar accuracy to hs-cTnT at the LoD. Because of its high precision at low concentrations, this hs-cTnI assay has favorable characteristics for this clinical application.


Assuntos
Infarto do Miocárdio/sangue , Troponina I/sangue , Troponina T/sangue , Idoso , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Histopathology ; 75(1): 74-80, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30820979

RESUMO

AIMS: This study is the first to systematically document histological features of fractures of known age in infants (≦12 months). It has been used to develop a tabulated database specifically to guide histopathologists to age fractures in children considered to have suffered accidental or non-accidental injury (NAI). Currently in the United Kingdom there are insufficient pathologists with experience in histological ageing of fractures to meet the medicolegal need for this examination. This study provides a practical tool that will allow those skilled paediatric and forensic pathologists currently involved in assessing infants for evidence of accidental or non-accidental injury a basis for extending their assessment into this area of unmet need. METHODS AND RESULTS: One hundred and sixty-nine fractures of known age at death were obtained from 52 anonymised infants over a period of 32 years (1985-2016 inclusive). Sections stained using haematoxylin and eosin (H&E) and Martius scarlet blue (MSB) were used to identify specific histological features and to relate them to fracture age. In 1999 the data were entered into a tabulated database for fractures accumulated between from 1985 to 1998 inclusive. Thereafter cases were added, and at 2-yearly intervals the accumulated data were audited against the previous database and adjustments made. CONCLUSIONS: This paper describes the final data set from the 2017 audit. The study was terminated at the end of 2016, as there had been no material changes in the data set for three consecutive audits.


Assuntos
Lesões Acidentais/patologia , Fraturas Ósseas/patologia , Lesões Acidentais/diagnóstico , Fatores Etários , Algoritmos , Autopsia , Síndrome da Criança Espancada/diagnóstico , Síndrome da Criança Espancada/patologia , Bases de Dados Factuais , Diagnóstico , Feminino , Patologia Legal , Consolidação da Fratura , Fraturas Ósseas/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Osteócitos/patologia , Reino Unido
3.
Soft Matter ; 13(8): 1554-1560, 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28120992

RESUMO

Nanogels are crosslinked polymer particles with a swollen size between 1 and 100 nm. They are of major interest for advanced surface coatings, drug delivery, diagnostics and biomaterials. Synthesising polyacid nanogels that show triggered swelling using a scalable approach is a key objective of polymer colloid chemistry. Inspired by the ability of polar surfaces to enhance nanoparticle stabilisation, we report the first examples of pH-responsive polyacid nanogels containing high -COOH contents prepared by a simple, scalable, aqueous method. To demonstrate their functionalisation potential, glycidyl methacrylate was reacted with the -COOH chemical handles and the nanogels were converted to macro-crosslinkers. The concentrated (functionalised) nanogel dispersions retained their pH-responsiveness, were shear-thinning and formed physical gels at pH 7.4. The nanogels were covalently interlinked via free-radical coupling at 37 °C to form transparent, ductile, hydrogels. Mixing of the functionalised nanogels with polymer dots enabled covalent assembly of fluorescent hydrogels.

4.
Clin Anat ; 30(3): 290-299, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28176374

RESUMO

Assessment serves the primary function of determining a student's competence in a subject. Several different assessment formats are available for assessing anatomical skills, knowledge and understanding and, as assessment can drive learning, a careful selection of assessments can help to engender the correct deep learning facility required of the safe clinical practitioner. The aim of this review was to survey the published literature to see whether higher education institutions are taking an andragogical approach to assessment. Five databases (EMBASE, ERIC, Medline, PubMed, and Web of Knowledge) were searched using standardized search terms with two limits applied (English language, and 2000 to the present). Among the 2,094 papers found, 32 were deemed suitable for this review. Current literature on assessment can be categorized into the following themes: assessment driven learning, types of assessments, frequency of assessments, and use of images in assessments. The consensus is to use a variety of methods, written and practical, to assess anatomical knowledge and skill in different domains. Institutions aim for different levels of Bloom's taxonomy for students at similar stages of their medical degree. Formative assessments are used widely, in differing formats, with mostly good effects on the final examination grade. In conclusion, a wide variety of assessments, each aimed at a different level of Bloom's taxonomy, are used by different institutions. Clin. Anat. 30:290-299, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Anatomia/educação , Avaliação Educacional , Humanos , Faculdades de Medicina , Estudantes de Medicina
5.
Biomacromolecules ; 17(7): 2448-58, 2016 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-27267971

RESUMO

In this study hydrogel composites are investigated that contain sacrificial pH-responsive collapsed hollow particles (CHPs) entrapped within a poly(acrylamide) (PAAm) network. The CHPs were prepared using a scalable (mainly) water-based method and had a bowl-like morphology that was comparable to that of red blood cells. The CHPs were constructed from poly(methyl methacrylate-co-methacrylic acid), which is a pH-responsive copolymer. The PAAm/CHP composite morphology was probed with optical microscopy, CLSM and SEM. These data showed the CHPs were dispersed throughout the PAAm network. Inclusion of the CHPs within the gel composites increased the modulus in a tunable manner. The CHPs fragmented at pH values greater than the pKa of the particles, and this process decreased the gel modulus to values similar to that of the parent PAAm hydrogel. CHPs containing a model drug were used to demonstrate pH-triggered release from PAAm/CHP and the release kinetics obeyed Fickian diffusion. The composite gels had low cytotoxicity as evidenced by Live/Dead and MTT assays. The hydrogel composites showed dual action pH-triggered softening with simultaneous drug release which occurred without a volume increase. The hydrogel composites may have potential application as enteric gels or for intra-articular drug delivery.


Assuntos
Materiais Biocompatíveis/química , Condrócitos/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polímeros/administração & dosagem , Polímeros/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/citologia , Humanos , Concentração de Íons de Hidrogênio
6.
Soft Matter ; 12(4): 1116-26, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26610808

RESUMO

Whilst hydrogels and hollow particles both continue to attract much attention in the literature there are few examples of hydrogel composites containing hollow particles. Here, we study composite polyacrylamide (PAAm) hydrogels containing micrometer-sized pH-responsive shell-crosslinked hollow particles (abbreviated as HPXL) based on poly(methylmethacrylate-co-methacrylic acid) functionalised with glycidyl methacrylate (GMA). The HPXL particles were prepared using our scaleable emulsion template method and inclusion of GMA was found to promote spherical hollow particle formation. The pendant vinyl groups from GMA enabled shell-crosslinked hollow particles to be prepared prior to formation of the PAAm/HPXL composite gels. The morphologies of the particles and composite gels were studied by optical microscopy, confocal laser scanning microscopy and scanning electron microscopy. Dynamic rheology measurements for the composite gels showed that the modulus variation with HPXL concentration could be described by a percolation model with a HPXL percolation threshold concentration of 4.4 wt% and a scaling exponent of 2.6. The composite gels were pH-responsive and largely maintained their mechanical properties over the pH range 4.0 to 8.0. Because the composite gels had tuneable mechanical properties (with modulus values up to 530 kPa) and were pH-responsive they are potential candidates for future wound healing or membrane applications.


Assuntos
Resinas Acrílicas/química , Hidrogéis/química , Cápsulas/química , Reagentes de Ligações Cruzadas/química , Elasticidade , Concentração de Íons de Hidrogênio , Ácidos Polimetacrílicos/química
7.
Calcif Tissue Int ; 96(6): 575-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25783012

RESUMO

We report clinical findings, bone mineral density (BMD) and bone biopsy data in ten children with features of classic idiopathic juvenile osteoporosis (IJO). We also screened the patients for mutations in LRP5 and LRP6. We found low BMD in the lumbar spine, the hip and distal radius. In the spine and distal radius, the reduction in BMD was more marked in the trabecular compartment. Biopsy confirmed that the trabecular compartment is more severely involved with reduction in bone formation and increase in bone resorption. No mutations in LRP5 and LRP6 could be identified. IJO is likely to be a heterogeneous bone disorder, and next-generation genomic sequencing studies may help reveal causative genes.


Assuntos
Predisposição Genética para Doença/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Osteoporose/genética , Osteoporose/patologia , Adolescente , Densidade Óssea , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Mutação
8.
Soft Matter ; 11(13): 2586-95, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25683792

RESUMO

We show that a new type of hydrogel can be prepared by covalently inter-linking binary blends of microgel (MG) particles and that the swelling ratio and modulus of the gels can be predicted from their composition. In previous work we established that physical gels of glycidyl methacrylate (GMA) functionalised poly(methyl methacrylate-co-methacrylic acid-co-ethyleneglycol dimethacrylate) microgel particles (GMA-MG) could be covalently inter-linked to give hydrogels, termed doubly crosslinked microgels, DX MGs. We build on this concept here by investigating the properties of DX MGs containing binary blends of GMA-MG particles and glycidyl oligo(ether ester) acrylate-functionalised microgel particles (GOE-MG). These new hydrogels were assembled by inter-linking nanoscale MG building blocks in the absence of small molecule monomers or crosslinkers. The volume fraction of GMA-MG particles used to prepare the GOE-GMA DX MGs was systematically varied. Rheology data showed that inclusion of GMA-MG and GOE-MG within the GOE-GMA DX MGs increased the modulus and yield strain, respectively, compared to the values measured for the respective physical gels. The data for the covalent GOE-GMA DX MG gels showed that the ductility increased with increasing GOE-MG content. GOE provided covalent inter-linking of the MG particles and also acted as a lubricant between particles due to its low Tg. By demonstrating compositionally determined swelling and mechanical properties for DX MG gels prepared using binary blends of MG particles, this study introduces a new, widely applicable, hydrogel construction assembly concept that is not available for conventional hydrogels.


Assuntos
Hidrogéis/química , Fenômenos Mecânicos , Concentração de Íons de Hidrogênio , Modelos Moleculares , Conformação Molecular , Polímeros/química , Reologia
9.
Langmuir ; 30(44): 13384-93, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-25313805

RESUMO

In this study we mixed low concentrations of graphene oxide (GO) with microgel (MG) particles and formed composite doubly cross-linked microgels (DX MG/GO) gels. The MG particles comprised poly(ethyl acrylate-co-methacrylic acid-co-1,4-butanediol diacrylate) with pendant glycidyl methacrylate units. The MG/GO mixed dispersions formed physical gels of singly cross-linked MGs (termed SX MG/GO), which were subsequently heated to produce DX MG/GO gels by free-radical reaction. The influence of the GO concentration on the mechanical properties of the SX MG/GO and DX MG/GO gels was investigated using dynamic rheology and static compression measurements. The SX MG/GO physical gels were injectable and moldable. The moduli for the DX MG/GO gels increased by a factor of 4-6 when only ca. 1.0 wt % of GO was included. The isostrain model was used to describe the variation of modulus with DX MG/GO composition. Inclusion of GO dramatically altered the stress dissipation and yielding mechanisms for the gels. GO acted as a high surface area, high modulus filler and played an increasing role in load distribution as the GO concentration increased. It is proposed that MG domains were dispersed within a percolated GO network. Comparison of the modulus data with those published for GO-free DX MGs showed that inclusion of GO provided an unprecedented rate of modulus increase with network volume fraction for this family of colloid gels. Furthermore, the DX MG/GO gels were biocompatible and the results imply that there may be future applications of these new systems as injectable load supporting gels for soft tissue repair.


Assuntos
Reagentes de Ligações Cruzadas/química , Géis/química , Grafite/química , Óxidos/química , Físico-Química , Reagentes de Ligações Cruzadas/síntese química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Propriedades de Superfície
11.
J Anal Toxicol ; 47(4): 317-323, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-36805935

RESUMO

Screening of postmortem blood and urine samples is used to identify compounds that may have contributed to an individual's death. Toxicologically significant compounds detected by the screen are then quantitated in blood to determine their likely effect upon death. In most laboratories, this is a two-step process. This study compares an established two-step screening and quantitative processes, utilizing a gas chromatography-mass spectrometry (GC-MS) screen followed by quantitation by GC-MS or high-performance liquid chromatography with diode array detection (HPLC-DAD), with a novel method utilizing liquid chromatography-high-resolution mass spectrometry (LC-HRMS). The LC-HRMS assay is able to screen postmortem blood and urine samples and simultaneously measure the concentration of toxicologically significant compounds in postmortem blood. Screening results of 200 postmortem blood samples and 103 postmortem urine samples by LC-HRMS and GC-MS showed that LC-HRMS detected key compounds in 125% more instances and there was a 60% increase in the number of compounds detected. Quantitative values generated using the LC-HRMS assay were within ±10% of values obtained using the established methods by GC-MS or HPLC-DAD. A retrospective analysis of turnaround times pre- and post-adoption of LC-HRMS showed a decrease for all of the compounds in the analysis, including a 43% reduction for free morphine and codeine, a 50% reduction for amphetamine and a 37% reduction for cocaine. Combining screening and quantitation reduced staffing requirements by 2 days for opiate quantitation and 1 day for most other analytes. The adoption of LC-HRMS also significantly reduced sample volume requirements. These results demonstrate that the adoption of LC-HRMS for simultaneous screening and quantitation delivered significant benefits in comparison to the two-step procedure.


Assuntos
Estudos Retrospectivos , Espectrometria de Massas , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão
12.
Radiology ; 264(1): 6-19, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22723559

RESUMO

Magnetic resonance (MR) imaging in patients with persistent low back pain and sciatica effectively demonstrates spine anatomy and the relationship of nerve roots and intervertebral disks. Except in cases with nerve root compression, disk extrusion, or central stenosis, conventional anatomic MR images do not help distinguish effectively between painful and nonpainful degenerating disks. Hypoxia, inflammation, innervation, accelerated catabolism, and reduced water and glycosaminoglycan content characterize degenerated disks, the extent of which may distinguish nonpainful from painful ones. Applied to the spine, "functional" imaging techniques such as MR spectroscopy, T1ρ calculation, T2 relaxation time measurement, diffusion quantitative imaging, and radio nucleotide imaging provide measurements of some of these degenerative features. Novel minimally invasive therapies, with injected growth factors or genetic materials, target these processes in the disk and effectively reverse degeneration in controlled laboratory conditions. Functional imaging has applications in clinical trials to evaluate the efficacy of these therapies and eventually to select patients for treatment. This report summarizes the biochemical processes in disk degeneration, the application of advanced disk imaging techniques, and the novel biologic therapies that presently have the most clinical promise.


Assuntos
Degeneração do Disco Intervertebral/diagnóstico , Degeneração do Disco Intervertebral/terapia , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Fenômenos Biomecânicos , Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Terapia Genética/métodos , Humanos , Mediadores da Inflamação/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/fisiopatologia , Dor Lombar/diagnóstico , Dor Lombar/metabolismo , Dor Lombar/fisiopatologia , Dor Lombar/terapia , Espectroscopia de Ressonância Magnética/métodos , Medição da Dor , Compostos Radiofarmacêuticos , Transplante de Células-Tronco
13.
Biomacromolecules ; 13(9): 2793-801, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22877136

RESUMO

The use of injectable pH-responsive doubly cross-linked microgels (DX microgels) to improve the mechanical properties of degenerated intervertebral discs is demonstrated for the first time. The microgel comprised methyl methacrylate (MMA), methacrylic acid (MAA), ethyleneglycol dimethacrylate (EGD) and glycidyl methacrylate (GM) and was poly(MMA/MAA/EGD)-GM. The GM facilitated covalent interparticle cross-linking. The DX microgels are shown to have tunable mechanical properties. Degeneration of model bovine intervertebral discs (IVDs) was induced using collagenase. When injected into degenerated IVDs the DX microgels were shown to improve the strain, modulus, toughness and resilience. The extent of mechanical property improvement was an increasing function of DX microgel concentration, suggesting tunability. Cytotoxicity studies showed that the DX microgel was biocompatible under the conditions investigated. The results of this study imply that injectable DX microgels have good potential as a future regenerative medicine strategy for restoring the mechanical properties of degenerated load-bearing soft tissue, such as IVDs.


Assuntos
Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Degeneração do Disco Intervertebral/tratamento farmacológico , Disco Intervertebral/efeitos dos fármacos , Metacrilatos/química , Animais , Bovinos , Colagenases/química , Reagentes de Ligações Cruzadas/química , Módulo de Elasticidade , Compostos de Epóxi/química , Géis , Concentração de Íons de Hidrogênio , Injeções , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia , Estrutura Molecular , Resistência ao Cisalhamento , Suporte de Carga
14.
Arthritis Rheum ; 62(12): 3695-705, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20722018

RESUMO

OBJECTIVE: Development of stem cell therapies for regenerating the nucleus pulposus (NP) are hindered by the lack of specific markers by which to distinguish NP cells from articular chondrocytes (ACs). The purpose of this study was to define the phenotype profile of human NP cells using gene expression profiling and to assess whether the identified markers could distinguish mesenchymal stem cell (MSC) differentiation to a correct NP cell phenotype. METHODS: Affymetrix MicroArray analyses were conducted on human NP cells and ACs, and differential expression levels for several positive (NP) and negative (AC) marker genes were validated by real-time quantitative polymerase chain reaction (PCR) analysis. Novel marker gene and protein expression was also assessed in human bone marrow-derived MSCs (BM-MSCs) and adipose tissue-derived MSCs (AD-MSCs) following differentiation in type I collagen gels. RESULTS: Analysis identified 12 NP-positive and 36-negative (AC) marker genes that were differentially expressed ≥20-fold, and for a subset of them (NP-positive genes PAX1, FOXF1, HBB, CA12, and OVOS2; AC-positive genes GDF10, CYTL1, IBSP, and FBLN1), differential expression was confirmed by real-time quantitative PCR. Differentiated BM-MSCs and AD-MSCs demonstrated significant increases in the novel NP markers PAX1 and FOXF1. AD-MSCs lacked expression of the AC markers IBSP and FBLN1, whereas BM-MSCs lacked expression of the AC marker IBSP but expressed FBLN1. CONCLUSION: This study is the first to use gene expression profiling to identify the human NP cell phenotype. Importantly, these markers can be used to determine the in vitro differentiation of MSCs to an NP-like, rather than an AC-like, phenotype. Interestingly, these results suggest that AD-MSCs may be a more appropriate cell type than BM-MSCs for use in engineering intervertebral disc tissue.


Assuntos
Células-Tronco Adultas/patologia , Cartilagem Articular/patologia , Diferenciação Celular , Perfilação da Expressão Gênica , Disco Intervertebral/patologia , Células-Tronco Mesenquimais/patologia , Fenótipo , Células-Tronco Adultas/metabolismo , Biomarcadores/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Cartilagem Articular/metabolismo , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Sialoproteína de Ligação à Integrina/metabolismo , Disco Intervertebral/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Fatores de Transcrição Box Pareados/metabolismo
15.
Cartilage ; 13(1_suppl): 1511S-1531S, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32680434

RESUMO

OBJECTIVE: Biomarkers in osteoarthritis (OA) could serve as objective clinical indicators for various disease parameters, and act as surrogate endpoints in clinical trials for disease-modifying drugs. The aim of this systematic review was to produce a comprehensive list of candidate molecular biomarkers for knee OA after the 2013 ESCEO review and discern whether any have been studied in sufficient detail for use in clinical settings. DESIGN: MEDLINE and Embase databases were searched between August 2013 and May 2018 using the keywords "knee osteoarthritis," "osteoarthritis," and "biomarker." Studies were screened by title, abstract, and full text. Human studies on knee OA that were published in the English language were included. Excluded were studies on genetic/imaging/cellular markers, studies on participants with secondary OA, and publications that were review/abstract-only. Study quality and bias were assessed. Statistically significant data regarding the relationship between a biomarker and a disease parameter were extracted. RESULTS: A total of 80 studies were included in the final review and 89 statistically significant individual molecular biomarkers were identified. C-telopeptide of type II collagen (CTXII) was shown to predict progression of knee OA in urine and serum in multiple studies. Synovial fluid vascular endothelial growth factor concentration was reported by 2 studies to be predictive of knee OA progression. CONCLUSION: Despite the clear need for biomarkers of OA, the lack of coordination in current research has led to incompatible results. As such, there is yet to be a suitable biomarker to be used in a clinical setting.


Assuntos
Biomarcadores , Colágeno Tipo I , Osteoartrite do Joelho , Peptídeos , Biomarcadores/análise , Biomarcadores/metabolismo , Colágeno Tipo I/sangue , Colágeno Tipo I/urina , Colágeno Tipo II/sangue , Colágeno Tipo II/urina , Marcadores Genéticos , Humanos , Osteoartrite do Joelho/diagnóstico , Osteoartrite do Joelho/metabolismo , Peptídeos/sangue , Peptídeos/urina , Líquido Sinovial/metabolismo , Fator A de Crescimento do Endotélio Vascular
16.
Rheumatology (Oxford) ; 48(8): 876-82, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19542215

RESUMO

OBJECTIVES: Our aim was to establish which tissue components express advanced glycation/lipoperoxidation end products (AGEs) and their receptor (RAGE) in skin from patients with SSc, and how their expression relates to the disease subtypes and various clinical parameters. METHODS: Skin punch biopsies were taken from the forearms of 61 SSc patients with lcSSc; 32 with calcinosis (lcSScCal) and 29 without lcSSc, 36 with the dcSSc subtype and 22 healthy control subjects. Immunohistochemical localization of AGE-CML [N(epsilon)-(carboxymethyl) lysine] and RAGE was assessed semi-quantitatively on the microvascular endothelium, dermal fibroblasts and the cutaneous extracellular matrix (ECM). The Kruskal-Wallis one-way ANOVA was used to compare data between groups. RESULTS: AGE-CML expression on the papillary dermis ECM of lcSScCal was greater than in the control group (P = 0.016). The reticular dermis of lcSScCal showed increased AGE-N(epsilon)-(carboxymethyl) lysine (CML) expression compared with controls (P = 0.002), dcSSc (P = 0.024) and lcSSc (P = 0.025). Increased immunostaining for RAGE was seen on the reticular dermis ECM of the lcSScCal group compared with controls (P = 0.007). The lcSScCal subgroup showed statistically significant correlations for AGE-CML, and to a lesser extent for RAGE, with increased RP duration. There was no consistent evidence that the expression of AGE-CML or RAGE related to autoantibody status, clinical or histological skin score or patient age. CONCLUSIONS: Our results indicate the possible contribution of AGE-CML deposition on the ECM in the dermis of the lcSScCal subgroup to the pathogenesis of formation of calcinotic deposits.


Assuntos
Calcinose/metabolismo , Produtos Finais de Glicação Avançada/análise , Receptores Imunológicos/análise , Escleroderma Sistêmico/metabolismo , Pele/química , Adulto , Análise de Variância , Biópsia , Calcinose/complicações , Calcinose/patologia , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/patologia , Pele/patologia , Estatísticas não Paramétricas , Fatores de Tempo
17.
Int Orthop ; 33(1): 281-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19023570

RESUMO

The objective of this study was to determine whether BMP-2 and -14, noggin, and chordin could be detected in human fractures and to assess their regional and cellular distribution. The expression of these proteins was detected by immunohistochemistry in an archive of human fractures. BMP-2 and BMP-14 expression was strongest in areas of cartilage formation and, to a lesser extent, in areas of bone formation. Within areas of cartilage formation, both BMP-2 and BMP-14 were expressed more strongly by the non-hypertrophic chondrocytes. The BMP inhibitors noggin and chordin were also expressed most intensely in areas of cartilage formation and there was no difference in their expression between the non-hypertrophic and hypertrophic chondrocytes. Our study demonstrates the expression of BMP-14 and the BMP inhibitors in human fractures for the first time, and our findings will contribute to an improved understanding of the physiological processes in bone repair.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Calo Ósseo/metabolismo , Proteínas de Transporte/metabolismo , Fraturas Ósseas/metabolismo , Glicoproteínas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Calo Ósseo/patologia , Cartilagem/metabolismo , Cartilagem/patologia , Condrócitos/metabolismo , Condrócitos/patologia , Consolidação da Fratura/fisiologia , Fraturas Ósseas/patologia , Fator 5 de Diferenciação de Crescimento/metabolismo , Humanos , Pessoa de Meia-Idade , Modelos Animais , Osteogênese/fisiologia , Adulto Jovem
18.
Nanoscale ; 11(16): 7921-7930, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30964497

RESUMO

Poly(ethylene glycol) (PEG) based hydrogels are amongst the most studied synthetic hydrogels. However, reports on PEG-based hydrogels with high mechanical strength are limited. Herein, a class of novel, well-defined PEG-based nanocomposite hydrogels with tunable mechanical strength are synthesised via ring-opening reactions of diglycidyl ethers with carboxylate ions. The pH responsive crosslinked polyacid nanogels (NG) in the dispersed phase act as high functionality crosslinkers which covalently bond to the poly(ethylene glycol) diglycidyl ethers (PEGDGE) as the continuous matrix. A series of NG-x-PEG-y-z gels are prepared where x, y and z are concentrations of NGs, PEGDGE and the PEGDGE molecular weight, respectively. The hydrogel compositions and nano-structural homogeneity of the NGs have strong impact on the enhancement of mechanical properties which enables property tuning. Based on this design, a highly compressive PEG-based nanocomposite hydrogel (NG-13-PEG-20-6000) exhibits a compressive stress of 24.2 MPa, compressive fracture strain greater than 98% and a fracture energy density as high as 1.88 MJ m-3. The tensile fracture strain is 230%. This is amongst one of the most compressive PEG-based hydrogels reported to-date. Our chemically crosslinked gels are resilient and show highly recoverable dissipative energy. The cytotoxicity test shows that human nucleus pulposus (NP) cells remained viable after 8 days of culture time. The overall results highlight their potential for applications as replacements for intervertebral discs or articular cartilages.


Assuntos
Hidrogéis/química , Polietilenoglicóis/química , Polietilenoimina/química , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Humanos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Nanogéis , Núcleo Pulposo/citologia , Núcleo Pulposo/efeitos dos fármacos , Núcleo Pulposo/metabolismo , Polietilenoglicóis/síntese química , Polietilenoglicóis/toxicidade , Polietilenoimina/síntese química , Polietilenoimina/toxicidade , Espalhamento a Baixo Ângulo , Resistência à Tração , Difração de Raios X
19.
Arthritis Res Ther ; 21(1): 5, 2019 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-30612576

RESUMO

BACKGROUND: The circadian clock plays a crucial role in regulating physiology and is important for maintaining immune homeostasis and responses to inflammatory stimuli. Inflammatory arthritis often shows diurnal variation in disease symptoms and disease markers, and it is now established that cellular clocks regulate joint inflammation. The clock gene Bmal1 is critical for maintenance of 24-h rhythms and plays a key role in regulating immune responses, as well as in aging-related processes. Fibroblast-like synoviocytes (FLS) are circadian rhythmic joint mesenchymal cells which are important for maintenance of joint health and play a crucial role in the development of inflammatory arthritis. The aim of this study was to investigate the importance of the joint mesenchymal cell circadian clock in health and disease. METHODS: Mice were generated which lack Bmal1 in Col6a1-expressing cells, targeting mesenchymal cells in the ankle joints. Joints of these animals were assessed by X-ray imaging, whole-mount staining and histology, and the composition of the synovium was assessed by flow cytometry. Arthritis was induced using collagen antibodies. RESULTS: Bmal1 deletion in joint mesenchymal cells rendered the FLS and articular cartilage cells arrhythmic. Targeted mice exhibited significant changes in the architecture of the joints, including chondroid metaplasia (suggesting a switch of connective tissue stem cells towards a chondroid phenotype), reductions in resident synovial macrophages and changes in the basal pro-inflammatory activity of FLS. Loss of Bmal1 in FLS rendered these resident immune cells more pro-inflammatory in response to challenge, leading to increased paw swelling, localised infiltration of mononuclear cells and enhanced cytokine production in a model of arthritis. CONCLUSIONS: This study demonstrates the importance of Bmal1 in joint mesenchymal cells in regulating FLS and chondrocyte development. Additionally, we have identified a role for this core clock component for restraining local responses to inflammation and highlight a role for the circadian clock in regulating inflammatory arthritis.


Assuntos
Fatores de Transcrição ARNTL/deficiência , Articulação do Tornozelo/metabolismo , Artrite Experimental/metabolismo , Ritmo Circadiano/fisiologia , Células-Tronco Mesenquimais/metabolismo , Fatores de Transcrição ARNTL/genética , Animais , Articulação do Tornozelo/diagnóstico por imagem , Artrite Experimental/diagnóstico por imagem , Artrite Experimental/genética , Células Cultivadas , Feminino , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos
20.
Fam Cancer ; 18(4): 445-449, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31240424

RESUMO

A 51-year old presented with a 6-month history of increasing pelvic/lower back pain with nocturnal waking and episodes of anorexia and vomiting. Examination revealed right torticollis and Horner's syndrome, and a large abdominal mass arising from the pelvis. Magnetic resonance and positron emission tomography imaging revealed (A) a 14 cm heterogeneous enhancing mass, abutting the left kidney with standardised uptake value max = 2.9, (B) a large heterogeneous enhancing pelvic mass (C) mesenteric adenopathy standardised uptake value max = 10.3 and (D) 6 cm right lung apex mass standardised uptake value max = 4.3. Computerised tomography-guided biopsy of lesion A was reported as neurofibroma with occasional atypia, lesion B a benign uterine leiomyoma and lesion C follicular lymphoma world health organisation Grade 2. Although she had been given the diagnosis of Neurofibromatosis Type-1 (NF1) 25-years previously following removal of an intradural extramedullary schwannoma she had no cutaneous stigmata of NF1. Genetic analysis of blood lymphocyte DNA identified a pathogenic variant in SMARCB1 confirming a diagnosis of schwannomatosis. Following 6-months chemotherapy for lymphoma, surgery was performed to remove lesion A. Histology revealed a malignant peripheral nerve sheath tumour with areas of low and high-grade change. An incidental, well-differentiated small bowel neuroendocrine carcinoma was also excised. Close surveillance continues with no recurrence after 6 years. This case study describes a novel finding of three separate synchronous primary malignancies in a patient with schwannomatosis and a proven SMARCB1 pathogenic variant.


Assuntos
Hemangioma/genética , Neoplasias Primárias Múltiplas/genética , Neurilemoma/genética , Neurofibromatoses/genética , Neurofibrossarcoma/genética , Proteína SMARCB1/genética , Neoplasias Cutâneas/genética , Feminino , Hemangioma/terapia , Síndrome de Horner/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/complicações , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/terapia , Neurilemoma/complicações , Neurilemoma/patologia , Neurilemoma/terapia , Neurofibromatoses/complicações , Neurofibromatoses/terapia , Neurofibrossarcoma/patologia , Neurofibrossarcoma/terapia , Neoplasias Retroperitoneais/genética , Neoplasias Retroperitoneais/terapia , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/terapia
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