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1.
J Sci Food Agric ; 102(7): 2723-2730, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34704255

RESUMO

BACKGROUND: Environmental conditions affect the quality of the fruits and their organoleptic properties. In low-tech greenhouses, these environmental conditions are frequently not optimal for crops. Therefore, the present study demonstrates the effects of the use of an integrated passive heating and cooling system in a greenhouse located in the Mediterranean area on the quality of pepper fruits. RESULTS: The results indicate that the passive system utilized (i) improved many parameters, such as average weight of fruits, °Brix, glucose and fructose content, and P and K content; (ii) increased the values of b* and hab *; and (iii) reduced total phenolic compounds, total amino acids content, and Fe and Zn content. However, the degree of the effect of the climatic factors on these parameters was also affected by harvest time. CONCLUSION: This novel study highlights the possibility of improving the nutritional quality of pepper fruits by modifying the environmental conditions through the use of passive heating and cooling systems at the same time as reducing the carbon footprint. © 2021 Society of Chemical Industry.


Assuntos
Capsicum , Clima Extremo , Piper nigrum , Capsicum/química , Frutas/química , Valor Nutritivo , Fenóis/análise
2.
Adv Mater ; 33(43): e2103737, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34486186

RESUMO

Design criteria for tissue-engineered materials in regenerative medicine include robust biological effectiveness, off-the-shelf availability, and scalable manufacturing under standardized conditions. For bone repair, existing strategies rely on primary autologous cells, associated with unpredictable performance, limited availability and complex logistic. Here, a conceptual shift based on the manufacturing of devitalized human hypertrophic cartilage (HyC), as cell-free material inducing bone formation by recapitulating the developmental process of endochondral ossification, is reported. The strategy relies on a customized human mesenchymal line expressing bone morphogenetic protein-2 (BMP-2), critically required for robust chondrogenesis and concomitant extracellular matrix (ECM) enrichment. Following apoptosis-driven devitalization, lyophilization, and storage, the resulting off-the-shelf cartilage tissue exhibits unprecedented osteoinductive properties, unmatched by synthetic delivery of BMP-2 or by living engineered grafts. Scalability and pre-clinical efficacy are demonstrated by bioreactor-based production and subsequent orthotopic assessment. The findings exemplify the broader paradigm of programming human cell lines as biological factory units to engineer customized ECMs, designed to activate specific regenerative processes.


Assuntos
Osteogênese
4.
Osteoarthr Cartil Open ; 3(4)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36313736

RESUMO

Objectives: In this study, we apply a clustering method to proteomic data sets from bovine and human models of post-traumatic osteoarthritis (PTOA) to distinguish clusters of proteins based on their kinetics of release from cartilage and examined these groups for PTOA biomarker candidates. We then quantified the effects of dexamethasone (Dex) on the kinetics of release of the cartilage media proteome. Design: Mass spectrometry was performed on sample medium collected from two separate experiments using juvenile bovine and human cartilage explants (3 samples/treatment condition) during 20- or 21-day treatment with inflammatory cytokines (TNF-α, IL-6, sIL-6R) with or without a single compressive mechanical injury. All samples were incubated with or without 100 nM Dex. Clustering was performed on the correlation between normalized averaged release vectors for each protein. Results: Our proteomic method identified the presence of distinct clusters of proteins based on the kinetics of their release over three weeks of culture. Clusters of proteins with peak release after one to two weeks had biomarker candidates with increased release compared to control. Dex rescued some of the changes in protein release kinetics the level of control, and in all conditions except control, there was late release of immune-related proteins. Conclusions: We demonstrate a clustering method applied to proteomic data sets to identify and validate biomarkers of early PTOA progression and explore the relationships between the release of spatially related matrix components. Dex restored the kinetics of release to many matrix components, but not all factors that contribute to cartilage homeostasis.

6.
Osteoarthr Cartil Open ; 2(4)2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34322675

RESUMO

OBJECTIVES: In this exploratory study, we used discovery proteomics to follow the release of proteins from bovine knee articular cartilage in response to mechanical injury and cytokine treatment. We also studied the effect of the glucocorticoid Dexamethasone (Dex) on these responses. DESIGN: Bovine cartilage explants were treated with either cytokines alone (10 ng/ml TNFα, 20 ng/ml IL-6, 100 ng/ml sIL-6R), a single compressive mechanical injury, cytokines and injury, or no treatment, and cultured in serum-free DMEM supplemented with 1% ITS for 22 days. All samples were incubated with or without addition of 100 nM Dex. Mass spectrometry and western blot analyses were performed on medium samples for the identification and quantification of released proteins. RESULTS: We identified 500 unique proteins present in all three biological replicates. Many proteins involved in the catabolic response of cartilage degradation had increased release after inflammatory stress. Dex rescued many of these catabolic effects. The release of some proteins involved in anabolic and chondroprotective processes was inconsistent, indicating differential effects on processes that may protect cartilage from injury. Dex restored only a small fraction of these to the control state, while others had their effects exacerbated by Dex exposure. CONCLUSIONS: We identified proteins that were released upon cytokine treatment which could be potential biomarkers of the inflammatory contribution to cartilage degradation. We also demonstrated the imperfect rescue of Dex on the effects of cartilage degradation, with many catabolic factors being reduced, while other anabolic or chondroprotective processes were not.

7.
J Exp Orthop ; 6(1): 19, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053993

RESUMO

BACKGROUND: An early detection of Osteoarthritis is urgently needed and still not possible until today. The aim of the study was to assess whether molecular biomarkers of cartilage turnover are associated with longitudinal change in knee cartilage thickness during a 2 year period in individuals with increased risk of developing knee osteoarthritis. A secondary aim was to assess whether prior knee injury or subjective patient-reported outcomes at baseline (BL) were associated with articular cartilage changes. Nineteen volleyball players (mean age 46.5 ± 4.9 years, 47% male) with a 30-year history of regular high impact training were recruited. The serum biomarkers Cpropeptide of type II procollagen (CPII), cartilage oligomeric matrix protein (COMP), collagenase generated carboxy-terminal neoepitope of type II collagen (sC2C), cartilage intermediate layer protein 2 (CILP-2), and the urine biomarkers C-telopeptide of type II collagen (CTX-II) and collagenase-generated peptide(s) of type II collagen (C2C-HUSA) were assessed at BL and at 2 year follow up (FU). Femorotibial cartilage thinning, thickening and absolute thickness change between BL and FU was evaluated from magnetic resonance imaging. Subjective clinical status at BL was evaluated by the International Knee Documentation Committee Subjective Knee Form and the Short-Form 36 Physical Component Score. RESULTS: CILP-2 was significantly higher at FU and linearly associated with the absolute cartilage thickness change during the experimental period. Prior injury was a predictor of increased absolute cartilage thickness change. CONCLUSION: Measuring the change in the cartilage biomarker CILP-2 might be a valid and sensitive method to detect early development of knee osteoarthritis as CILP-2 appears to be related to cartilage thickness loss in certain individuals with increased risk of developing knee osteoarthritis. Prior knee injury may be predictive of increased articular cartilage thickness change.

8.
Front Plant Sci ; 10: 301, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31001289

RESUMO

The horticultural industry demands high-quality resources to achieve excellence in yield and optimal revenues. Nitrogen is a pivotal nutrient to accomplish these goals for plant growth and product quality. However, competition for water in semi-arid regions can force the use of brackish waters, which can impair N uptake. The lower N uptake can be due to several reasons, such as an antagonism between ions, an absence of ATP, and/or alteration of N metabolism. The effect of supplying N as NO 3 - alone or in combination with NH 4 + , coupled with low or high salinity (8 or 20 mM NaCl), has been studied in sweet pepper fruits (Capsicum annuum L. cv. Melchor). The application of NH 4 + at high salinity affected chromatic parameters (a∗, b∗, and C∗), while chlorophyll a and b levels declined and ß-carotene increased. The concentrations of P, K, Ca, Mg, and Cu were reduced in the fruits of plants irrigated with NH 4 + . The concentration of Na was only reduced when NH 4 + was supplied. Likewise, the concentration of total phenolics was also reduced at high salinity. However, total protein was unaffected. The amino acid profile was altered by the supply of NH 4 + , which reduced the concentrations of histidine and phenylalanine. Moreover, the concentrations of putrescine and cadaverine were increased by NH 4 + at high salinity, whereas that of cadaverine was reduced by NH 4 + at low salinity. The observed changes in fruit quality triggered by salinity, under the conditions of this study, should be borne in mind for this crop with regard to the envisaged palliative effect of the supply of N- NH 4 + .

9.
J Exp Orthop ; 4(1): 7, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28229430

RESUMO

BACKGROUND: This study aimed the feasibility to assess longitudinal changes in biomarkers of cartilage turnover and to determine their relationship with patient-rated outcomes over 2 years in volleyball athletes. METHODS: Thirty-seven athletes were studied: 18 adolescents (age 15.9 ± 0.64 years) in a 2-year intensive volleyball training program and 19 adult recreational volleyball players (age 46.5 ± 4.9 years). Blood and serum samples were taken at baseline (BL) and 2-year follow-up (FU). Subjects completed the International Knee Documentation Committee (IKDC) Subjective Knee Form and the Short-Form 36 (SF-36) at BL. RESULTS: Thirteen adolescents (72%) had open growth plates at BL (BL open adolescents), the rest had closed growth plates at BL (BL closed adolescents), and all but one adolescent had closed growth plates at FU as assessed by MRI. BL open and closed adolescents had greater levels of the cartilage degradation-based biomarkers 45 mer collagenase peptide of type II collagen (C2C-HUSA) and C-telopeptide of type II collagen (CTX-II) than adults. BL open adolescents showed decreases in C2CHUSA, collagen synthesis marker C-propeptide of type II procollagen (CPII), and CTXII, and adults showed increases in cartilage intermediate layer protein 2 (CILP-2) and C2C-HUSA. In adolescents, IKDC scores were correlated with CPII changes. In adults, SF-36 Physical Component Scores were correlated with cartilage oligomeric matrix protein (COMP) changes. CONCLUSION: Significant differences in biomarker levels over time show the feasibility to assess their changes. Greater levels of C2C-HUSA and CTX-II in adolescents than in adults may reflect increased cartilage turnover in response to higher joint loading. CPII and COMP may be more reflective of subjective patient outcomes. These biomarkers may thus be useful in assessing mechanical loading-induced cartilage changes, their associated symptoms, and Osteoarthritis risk in athletes.

10.
J Agric Food Chem ; 65(4): 711-717, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28075582

RESUMO

We investigated the effect of supplying nitrogen, as NO3- or as NO3-/NH4+, on the composition of fruits of sweet pepper (Capsicum annuum L. cv. Melchor) plants grown with different CO2 concentrations ([CO2]): ambient or elevated (800 µmol mol-1). The results show that the application of NH4+ and high [CO2] affected the chroma related to the concentrations of chlorophylls. The concentrations of Ca, Cu, Mg, P, and Zn were significantly reduced in the fruits of plants nourished with NH4+, the loss of Fe being more dramatic at increased [CO2], which was also the case with the protein concentration. The concentration of total phenolics was increased by NH4+, being unaffected by [CO2]. Globally, the NH4+ was the main factor that affected fruit free amino acid concentrations. Polyamines were affected differently: putrescine was increased by elevated [CO2], while the response of cadaverine depended on the form of N supplied.


Assuntos
Aminoácidos/metabolismo , Capsicum/metabolismo , Dióxido de Carbono/metabolismo , Nitrogênio/metabolismo , Poliaminas/metabolismo , Aminoácidos/análise , Capsicum/química , Capsicum/crescimento & desenvolvimento , Dióxido de Carbono/análise , Clorofila/análise , Clorofila/metabolismo , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Nitrogênio/química , Poliaminas/análise
11.
Funct Plant Biol ; 44(6): 573-586, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32480589

RESUMO

In many plant species, long-term exposure to elevated CO2 concentration results in a reduction in photosynthetic capacity, known as acclimation. This process is mainly explained by a feedback inhibition mechanism. The supply of a fraction of the nitrogen (N) in the nutrient solution as NH4+ can play an important role in the maintenance of photosynthetic activity and could mitigate the acclimation process. The aims of the present work were to study the photosynthetic response of sweet pepper (Capsicum annuum L.) to CO2 enrichment in Mediterranean greenhouse conditions, throughout the crop growth cycle and to evaluate the supply of NH4+ in the nutrient solution as a strategy to enhance the long-term response to CO2 at different levels of salinity. The experiment was conducted in two identical greenhouses: one with CO2 enrichment according to the ventilation, maintaining a high concentration when the vents were closed and a near-atmospheric level when the vents were open and one without. Sweet pepper plants were grown in both greenhouses, being irrigated with two levels of water salinity and two N sources: (i) NO3- and (ii) NO3- plus NH4+. A reduction in the response of photosynthesis to high CO2 concentration was found in the enriched plants after 135 days of CO2 supply, with respect to the reference plants. The leaf photosynthesis rate measured at high CO2 concentration showed a closer relationship with the leaf N concentration than the non-structural carbohydrate concentration. The relative yield gain of the CO2-enriched plants progressively decreased after reaching a maximum value; this was probably associated with the photosynthetic acclimation process. This decrease was delayed by the use of NH4+ in the nutrient solution at low salinity. Knowledge of the crop phase when acclimation to high CO2 concentration occurs can be the basis for deciding when to impose an early cessation of CO2 application, as a strategy to improve the economic efficiency of CO2 supply in Mediterranean conditions.

12.
J Sci Food Agric ; 95(14): 2924-30, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25471904

RESUMO

BACKGROUND: Different nitrogen inputs and/or development under adverse water conditions (water stress/low quality and/or high salinity/electrical conductivity), such as those prevailing in Almeria (Mediterranean coast, south-east Spain), may affect overall fruit and vegetable quality. This study evaluated the influence of salinity and nitrogen reduction in hydroponic nutrient solution on strawberry fruit quality and nutritional compounds (Fragaria × ananassa Duch., cv. Primoris). RESULTS: Strawberries obtained under salinity treatments recorded the highest values for soluble solids content (SSC; all samplings); fruit taste was thus enhanced. Additionally, salinity improved fruit nutritional value, with higher contents of antioxidants compounds (first sampling). During first and second samplings, strawberries grown under N reduction and non-saline conditions showed higher values for firmness compared to fruits developed under other treatments. Regarding health-related compounds, few differences were found except for total polyphenols concentration and antioxidant activity for the first sampling, where strawberries grown under saline treatments obtained the highest values for both parameters. CONCLUSION: The use of low-quality waters, such as those found in Almeria (salinity, N9S and N5S) and low nitrogen inputs (N5, avoid environmental impact) for strawberry cultivation does not exert a negative impact on overall quality. Positive differences could be found in SSC, firmness and health-related compounds when compared against the control treatment (N9).


Assuntos
Antioxidantes/metabolismo , Fragaria/metabolismo , Frutas/metabolismo , Nitrogênio/metabolismo , Cloreto de Sódio/metabolismo , Estresse Fisiológico , Paladar , Antioxidantes/farmacologia , Dieta , Ecossistema , Frutas/normas , Dureza , Humanos , Hidroponia , Valor Nutritivo , Polifenóis/metabolismo , Polifenóis/farmacologia , Salinidade , Tolerância ao Sal , Espanha , Água
13.
J Biol Chem ; 289(30): 20908-16, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-24917676

RESUMO

To identify patients at risk for progressive joint damage, there is a need for early diagnostic tools to detect molecular events leading to cartilage destruction. Isolation and characterization of distinct cartilage oligomeric matrix protein (COMP) fragments derived from cartilage and released into synovial fluid will allow discrimination between different pathological conditions and monitoring of disease progression. Early detection of disease and processes in the tissue as well as an understanding of the pathologic mechanisms will also open the way for novel treatment strategies. Disease-specific COMP fragments were isolated by affinity chromatography of synovial fluids from patients with rheumatoid arthritis, osteoarthritis, or acute trauma. Enriched COMP fragments were separated by SDSPAGE followed by in-gel digestion and mass spectrometric identification and characterization.Using the enzymes trypsin, chymotrypsin, and Asp-N for the digestions, an extensive analysis of the enriched fragments could be accomplished. Twelve different neoepitopes were identified and characterized within the enriched COMP fragments. For one of the neoepitopes, Ser77, an inhibition ELISA was developed. This ELISA quantifies COMP fragments clearly distinguishable from total COMP. Furthermore, fragments containing the neoepitope Ser77 were released into the culture medium of cytokine (TNF-α and IL-6/soluble IL-6 receptor)-stimulated human cartilage explants. The identified neoepitopes provide a complement to the currently available commercial assays for cartilage markers. Through neoepitope assays, tools to pinpoint disease progression, evaluation methods for therapy, and means to elucidate disease mechanisms will be provided.


Assuntos
Proteína de Matriz Oligomérica de Cartilagem , Cromatografia de Afinidade , Epitopos , Artropatias/metabolismo , Espectrometria de Massas , Líquido Sinovial , Adulto , Proteína de Matriz Oligomérica de Cartilagem/química , Proteína de Matriz Oligomérica de Cartilagem/isolamento & purificação , Proteína de Matriz Oligomérica de Cartilagem/metabolismo , Células Cultivadas , Epitopos/química , Epitopos/isolamento & purificação , Epitopos/metabolismo , Humanos , Interleucina-6/metabolismo , Artropatias/patologia , Receptores de Interleucina-6/metabolismo , Líquido Sinovial/química , Líquido Sinovial/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Reumatol Clin ; 9(1): 18-23, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22938792

RESUMO

AIM: To determine whether rheumatoid arthritis (RA) patients who have been prescribed biological agents exhibit a different comorbidity burden than RA patients who take disease-modifying antirheumatic drugs (DMARDs) alone, and to understand the association between comorbidity and other variables, as well as the association between comorbidity and multimorbidity. METHODS: This observational case-control study included 114 RA patients treated with biological agents and a control group comprising 163 sex- and age-matched RA patients treated with DMARDs only. Current and previous data regarding the patients' disease activity, comorbidities, and treatments were collected. The data were analysed using bivariate and multivariate regression models. RESULTS: The patients who were prescribed biological agents exhibited poorer disease control, received more DMARDs and steroids, and underwent more total joint arthroplasties compared with the patients in the control group. However, the risk factors for cardiovascular disease and the comorbidity frequency were similar between cases and controls. The most prevalent comorbidities were hypertension, obesity, and respiratory, thyroid, and upper gastrointestinal disorders. The incidence of cardiovascular disease was low, and only 29% of the patients exhibited multimorbidities. A bivariate association of age, late diagnosis, joint replacements and a high score on the health assessment questionnaire score (HAQ) with comorbidity was observed. There were also correlations between the Charlson index and age, joint reconstructive surgery, disease activity (DAS28), and HAQ score. However, when binary logarithmic regression models were applied, only patient age remained significantly associated with comorbidity and multimorbidity [hazard ratio, 1.08; 95% confidence interval, 1.05-1.12; p<0.0005]. CONCLUSION: RA patients taking biological drugs have a comorbidity burden equivalent to those treated with DMARDs alone. Age is the main predictive factor of comorbidity in these patients.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/epidemiologia , Adalimumab , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Murinos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Comorbidade , Etanercepte , Feminino , Humanos , Imunoglobulina G/uso terapêutico , Infliximab , Modelos Logísticos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Análise Multivariada , Receptores do Fator de Necrose Tumoral/uso terapêutico , Estudos Retrospectivos , Rituximab , Espanha , Resultado do Tratamento , Adulto Jovem
15.
Reumatol Clin ; 7(6): 380-4, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-22078695

RESUMO

OBJECTIVE: To determine the annual number and trend of prostheses implanted in patients with rheumatoid arthritis (RA) at our hospital during the past decade. MATERIALS AND METHODS: Retrospective observational study. Patients were collected through an extensive search of the database of the Clinical Documentation Service between 1998 and 2007. The data was extracted from medical records using a predesigned questionnaire. Statistical analysis of longitudinal prostheses was made by Cochrane's Q test and the Kaplan-Meier method. RESULTS: Sixty-one RA patients were operated on with 78 prostheses as a direct result of their disease at our hospital between 1998 and 2007. Most were women (80%) with positive rheumatoid factor (84%). The mean age was 58 years, and the average time since onset of RA was 13 years. All but one had previously received antirheumatic drugs (88% methotrexate), but only 11% had biological therapy. No changes were observed in the number of arthroplasties as a whole over a decade, although there was a trend towards reduction in the number of patients that required a knee replacement for the first time (Cochrane Q, P=0.05). CONCLUSION: We observed no significant changes in trends in the number of new joint replacement procedures as a whole in the past decade at our hospital, although the number of patients that required knee replacement for the first time as a direct result of their underlying disease seems to have declined in the last decade.


Assuntos
Artrite Reumatoide/cirurgia , Artroplastia de Quadril/tendências , Artroplastia do Joelho/tendências , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espanha
16.
Dig Dis Sci ; 54(2): 300-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18600455

RESUMO

This work focuses on studying the early events associated with pancreatic damage after retrograde infusion through the pancreatic duct in rats. We have analyzed changes in calcium homeostasis and secretory response in pancreatic acini from rats with taurocholate-induced acute pancreatitis. Moreover, in order to test whether pancreatic duct manipulation can trigger damage inside pancreatic acinar cells, we have studied both parameters in acini from animals infused with saline. Our study demonstrates that taurocholate causes evident damage to acinar cells, impairing both calcium homeostasis and secretory response to CCK. In saline, a significant decrease in calcium cytosolic response to CCK was observed. Calcium disturbances similar to those observed in acute pancreatitis appear before secretion blockade and inflammation processes in saline treated rats. These results could be interesting since pancreatitis is associated to clinical procedures that require duct manipulation such as endoscopic retrograde cholangiopancreatography.


Assuntos
Cálcio/metabolismo , Colecistocinina/metabolismo , Ductos Pancreáticos/lesões , Pancreatite Necrosante Aguda/metabolismo , Ácido Taurocólico/administração & dosagem , Amilases/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Citosol/metabolismo , Homeostase , Masculino , Pâncreas/patologia , Pancreatite Necrosante Aguda/induzido quimicamente , Pancreatite Necrosante Aguda/patologia , Ratos , Ratos Wistar , Cloreto de Sódio/administração & dosagem , Substância P/metabolismo , Ácido Taurocólico/toxicidade
17.
Matrix Biol ; 23(6): 381-91, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15533759

RESUMO

The synthesis and contents of extracellular non-collagenous matrix macromolecules was studied in early and late human osteoarthritic (OA) cartilage obtained at surgery for sarcomas in the lower extremities (normal and early OA) or for total knee replacement (late stage OA). The early OA samples were those that had some fibrillation in the joint by visual examination. One group had fibrillation in the area sampled and the other group had no fibrillation. Cartilage was taken from the same topographical area on the medial femoral condyle in all the samples, labeled with [3H]leucine and [35S]sulfate for 4 h at 37 degrees C and extracted with 4 M guanidine-HCl. Analysis of the extracts showed that the total amount of proteoglycans relative to hydroxyproline content was higher in the early and late OA than in the normal cartilage. These proteoglycans showed a relatively lower [35S]sulfate incorporation into GAG chains and a higher [3H]leucine incorporation. The pattern of newly synthesized proteins was altered similarly in early and late OA. Notably, synthesis of cartilage oligomeric matrix protein (COMP), fibronectin, and cartilage intermediate layer protein (CILP) was increased, also reflected in their abundance as determined by enzyme-linked immunosorbent assay (ELISA). Collagen synthesis appeared significantly increased only in the late stage OA. The observed altered composition and pattern of biosynthesis indicate that the joint undergoes metabolic alterations early in the disease process, even before there is overt fibrillation of the tissue. The early OA samples studied appear to represent two distinct groups of early lesions in different stages of the process of cartilage deterioration as shown by their differences in relative rates of synthesis and abundance of proteins.


Assuntos
Matriz Extracelular/metabolismo , Osteoartrite/metabolismo , Idoso , Azul Alciano/farmacologia , Peso Corporal , Cartilagem/metabolismo , Cartilagem Articular/metabolismo , Cromatografia , Cromatografia por Troca Iônica , Colágeno/química , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hidroxiprolina/química , Leucina/química , Masculino , Pessoa de Meia-Idade , Osteoartrite/patologia , Pró-Colágeno/química , Proteoglicanas/química , Proteoglicanas/metabolismo , Temperatura
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