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1.
Life Sci ; 329: 121944, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37453577

RESUMO

The relation between obesity and osteoarthritis (OA) development has been traditionally explained as consequence of the excessive joint effort derived of overweight. However, in the last two decades a metabolic OA has been suggested through diverse molecular mechanism implying metabolic syndrome, although more investigation must be conducted to elucidate it. Metabolic syndrome is responsible of the release of diverse inflammatory cytokines, specially the increased adipokine in obesity, causing a chronic low-grade inflammatory status that alters the joint homeostasis. In this scenario, the microbiota dysbiosis contribute by worsening the low-grade chronic inflammation or causing metabolic disorders mediated by endotoxemia generated by an increased lipopolysaccharides intake. This results in joint inflammation and cartilage degradation, which contributes to the development of OA. Also, the insulin resistance provoked by type 2 Diabetes contributes to the OA development. When intake patterns are considered, some coincidences can be pointed between the food patterns associated to the metabolic syndrome and the food patterns associated to OA development. Therefore, these coincidences support the idea of a molecular mechanism of the OA development caused by the molecular mechanism generated under the metabolic syndrome status. This review points the relation between metabolic syndrome and OA, showing the connected molecular mechanisms between both pathologies as well as the shared dietary patterns that promote or prevent both pathologies.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Microbiota , Osteoartrite , Humanos , Síndrome Metabólica/metabolismo , Diabetes Mellitus Tipo 2/complicações , Osteoartrite/patologia , Inflamação/metabolismo , Obesidade/complicações , Obesidade/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-34065498

RESUMO

This article provides a vision of the importance of the recovery process for the prevention of injuries in young athletes. From a sports psychology perspective, it presents a proposal for an optimisation programme to reduce the negative impact of exertion and subsequent risk of injury. The 4BR programme consists of three sub-programmes (technician advice, vulnerability detection, and the implementation of four recovery habit blocks). An interdisciplinary approach is taken to configure the four healthy blocks: nutrition-hydration, relaxation-rest, social life and personal moments. It demonstrates the importance of personalised adaptation to the sports context and moment in order to achieve maximum effectiveness of the proposed 4BR programme, which comprises workshops, exercises, evaluation systems and information feedback. The presented programme facilitates recovery, optimizes the return to training and reduces the risk of intrinsic injuries in young people. The conclusion drawn from the study is that there is a need to conduct further research to find empirical evidence of the positive effects of applying the 4BR programme to different sports.


Assuntos
Traumatismos em Atletas , Esportes , Adolescente , Atletas , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/prevenção & controle , Exercício Físico , Terapia por Exercício , Humanos
3.
Artigo em Inglês | MEDLINE | ID: mdl-32947943

RESUMO

Protected natural areas (PNAs) can be a source of health and well-being, but little research has been carried out regarding outcomes in terms of satisfaction (the difference between motivations and benefits). Inspired by previous research that examines the motivations and benefits perceived by visitors to various PNAs in Canada, and based on importance-performance analysis (IPA) and service quality gap (GAP) analysis theory, the aim of this study was to identify the outcomes generated by protected areas in terms of satisfaction, especially with regard to the PNAs' individual protection categories. The study was based on survey data from visitors (n = 360) to three PNAs in Catalonia: one national park, one natural park and one periurban park. The results indicate that anticipated environmental, psychological, physical and social benefits were of major personal value in choosing to visit a PNA. The results indicate that, generally, visitors were satisfied with regard to the benefits anticipated. Differences between parks in this respect could be explained in part by sociodemographic factors and visitors' behavior. The results are discussed in terms of their applicability and how they relate to the role of PNAs in the promotion of visitors' health and well-being.


Assuntos
Satisfação Pessoal , Recreação , Adulto , Canadá , Conservação dos Recursos Naturais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parques Recreativos , Espanha , Adulto Jovem
4.
J Transl Med ; 18(1): 356, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948200

RESUMO

BACKGROUND: Mesenchymal stromal cells are a safe and promising option to treat knee osteoarthritis as previously demonstrated in different clinical trials. However, their efficacy, optimal dose and addition of adjuvants must be determined. Here, we evaluated the clinical effects of a dose of 100 × 106 bone marrow mesenchymal stromal cells (BM-MSCs) in combination with Platelet Rich Plasma (PRGF®) as adjuvant in a randomized clinical trial. METHODS: A phase II, multicenter, randomized clinical trial with active control was conducted. Sixty patients diagnosed with knee OA were randomly assigned to 3 weekly doses of PRGF® or intraarticular administration of 100 × 106 cultured autologous BM-MSCs plus PRGF®. Patients were followed up for 12 months, and pain and function were assessed using VAS and WOMAC and by measuring the knee range of motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage. RESULTS: No adverse effects were reported after BM-MSC administration or during follow-up. According to VAS, the mean value (SD) for PRGF® and BM-MSC with PRGF® went from 5 (1.8) to 4.5 (2.2) (p = 0.389) and from 5.3 (1.9) to 3.5 (2.5) (p = 0.01), respectively at 12 months. In WOMAC, the mean (SD) baseline and 12-month overall WOMAC scores in patients treated with PRGF® was 31.9 (16.2) and 22.3 (15.8) respectively (p = 0.002) while that for patients treated with BM-MSC plus PRGF® was 33.4 (18.7) and 23.0 (16.6) (p = 0.053). Although statistical significances between groups have been not detected, only patients being treated with BM-MSC plus PRGF® could be considered as a OA treatment responders following OARSI criteria. X-ray and MRI (WORMS protocol) revealed no changes in knee joint space width or joint damage. CONCLUSIONS: Treatment with BM-MSC associated with PRGF® was shown to be a viable therapeutic option for osteoarthritis of the knee, with clinical improvement at the end of follow-up. Further phase III clinical trials would be necessary to confirm the efficacy. Trial registration Clinical Trials.gov identifier NCT02365142. Nº EudraCT: 2011-006036-23.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Osteoartrite do Joelho , Plasma Rico em Plaquetas , Humanos , Injeções Intra-Articulares , Osteoartrite do Joelho/terapia , Resultado do Tratamento
5.
J Am Soc Mass Spectrom ; 31(3): 527-537, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32126778

RESUMO

Recently, the olive oil industry has been the subject of harsh criticism for false labeling and even adulterating olive oils. This situation in which both the industry and the population are affected leads to an urgent need to increase controls to avoid fraudulent activities around this precious product. The aim of this work is to propose a new analytical platform by coupling electrospray ionization (ESI), differential mobility analysis (DMA), and mass spectrometry (MS) for the analysis of olive oils based on the information obtained from the chemical fingerprint (nontargeted analyses). Regarding the sample preparation, two approaches were proposed: (i) sample dilution and (ii) liquid-liquid extraction (LLE). To demonstrate the feasibility of the method, 30 olive oil samples in 3 different categories were analyzed, using 21 of them to elaborate the classification model and the remaining 9 to test it (blind samples). To develop the prediction model, principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA) were used. The overall success rate of the classification to differentiate among extra virgin olive oil (EVOO), virgin olive oil (VOO), and lampante olive oil (LOO) was 89% for the LLE samples and 67% for the diluted samples. However, combining both methods, the ability to differentiate EVOO from lower-quality oils (VOO and LOO) and the edible oils (EVOO and VOO) from nonedible oil (LOO) was 100%. The results show that ESI-DMA-MS can become an effective tool for the olive oil sector.


Assuntos
Azeite de Oliva/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Análise Discriminante , Análise de Alimentos/métodos , Análise dos Mínimos Quadrados , Extração Líquido-Líquido , Análise de Componente Principal
6.
J Transl Med ; 16(1): 213, 2018 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-30064455

RESUMO

BACKGROUND: Mesenchymal stromal cells (MSCs) are a promising option to treat knee osteoarthritis (OA). Their safety and usefulness have been reported in several short-term clinical trials but less information is available on the long-term effects of MSC in patients with osteoarthritis. We have evaluated patients included in our previous randomized clinical trial (CMM-ART, NCT02123368) to determine their long-term clinical effect. MATERIALS: A phase I/II multicenter randomized clinical trial with active control was conducted between 2012 and 2014. Thirty patients diagnosed with knee OA were randomly assigned to Control group, intraarticularly administered hyaluronic acid alone, or to two treatment groups, hyaluronic acid together with 10 × 106 or 100 × 106 cultured autologous bone marrow-derived MSCs (BM-MSCs), and followed up for 12 months. After a follow up of 4 years adverse effects and clinical evolution, assessed using VAS and WOMAC scorings are reported. RESULTS: No adverse effects were reported after BM-MSCs administration or during the follow-up. BM-MSCs-administered patients improved according to VAS, median value (IQR) for Control, Low-dose and High-dose groups changed from 5 (3, 7), 7 (5, 8) and 6 (4, 8) to 7 (6, 7), 2 (2, 5) and 3 (3, 4), respectively at the end of follow up (Low-dose vs Control group, p = 0.01; High-dose vs Control group, p = 0.004). Patients receiving BM-MSCs also improved clinically according to WOMAC. Control group showed an increase median value of 4 points (- 11;10) while Low-dose and High-dose groups exhibited values of - 18 (- 28;- 9) and - 10 (- 21;- 3) points, respectively (Low-dose vs Control group p = 0.043). No clinical differences between the BM-MSCs receiving groups were found. CONCLUSIONS: Single intraarticular injection of in vitro expanded autologous BM-MSCs is a safe and feasible procedure that results in long-term clinical and functional improvement of knee OA.


Assuntos
Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Osteoartrite do Joelho/terapia , Idoso , Feminino , Seguimentos , Humanos , Ácido Hialurônico/efeitos adversos , Injeções Intra-Articulares , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Dor/etiologia , Dor/fisiopatologia , Transplante Autólogo , Escala Visual Analógica
7.
Anal Chem ; 90(11): 6885-6892, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29694027

RESUMO

Two differential mobility analyzers (DMAs) acting as narrow band mobility filters are coupled in series, with a thermal fragmentation cell placed in between, such that parent ions selected in DMA1 are fragmented in the cell at atmospheric pressure, and their product ions are analyzed on DMA2. Additional mass spectrometer analysis is performed for ion identification purposes. A key feature of the tandem DMA is the short residence time (∼0.2 ms) of ions in the analyzer, compared to tens of milliseconds in drift tube ion mobility spectrometers (IMS). Ion fragmentation within the analyzer and associated mobility tails are therefore negligible for a DMA but not necessarily so in conventional IMS. This advantage of the DMA is demonstrated here by sharply defined product ion mobility peaks. Ambient pressure ion fragmentation has been previously demonstrated by both purely thermal means as well as rapidly oscillating intense electric fields. Our purely thermal fragmentation cell here achieves temperatures up to 700 °C measured inside the heating coil of a cylindrical ceramic heater, through whose somewhat colder axis we direct a beam of mobility-selected ions. We investigate tandem separation of chloride adducts from the explosives EGDN, nitroglycerine (NG), PETN, and RDX and from deprotonated TNT. Atmospheric pressure fragmentation of the first three ions yields one or several previously reported fragments, providing highly distinctive tandem DMA channels for explosive identification at 1 atm. RDX ions had not been previously fragmented at ambient pressure, yet [RDX + Cl]- converts up to 7% (at 300 °C) into a 166 m/ z product. The known high thermal resilience of TNT is confirmed here by its rather modest conversion, even when the ceramic is heated to 700 °C. At this temperature some previously reported fragments are found, but their mobilities are fairly close to each other and to the one of the far more abundant parent ion, making their identification by mobility alone problematic. We anticipate that moderately higher fragmenter temperatures will produce smaller fragments with mobilities readily separated from that of [TNT - H]-.

8.
J Transl Med ; 14(1): 246, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27565858

RESUMO

BACKGROUND: Mesenchymal stromal cells are a promising option to treat knee osteoarthritis. Their safety and usefulness must be confirmed and the optimal dose established. We tested increasing doses of bone marrow mesenchymal stromal cells (BM-MSCs) in combination with hyaluronic acid in a randomized clinical trial. MATERIALS: A phase I/II multicenter randomized clinical trial with active control was conducted. Thirty patients diagnosed with knee OA were randomly assigned to intraarticularly administered hyaluronic acid alone (control), or together with 10 × 10(6) or 100 × 10(6) cultured autologous BM-MSCs, and followed up for 12 months. Pain and function were assessed using VAS and WOMAC and by measuring the knee motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage. RESULTS: No adverse effects were reported after BM-MSC administration or during follow-up. BM-MSC-administered patients improved according to VAS during all follow-up evaluations and median value (IQR) for control, low-dose and high-dose groups change from 5 (3, 7), 7 (5, 8) and 6 (4, 8) to 4 (3, 5), 2 (1, 3) and 2 (0,4) respectively at 12 months (low-dose vs control group p = 0.005 and high-dose vs control group p < 0.009). BM-MSC-administered patients were also superior according to WOMAC, although improvement in control and low-dose patients could not be significantly sustained beyond 6 months. On the other hand, the BM-MSC high-dose group exhibited an improvement of 16.5 (12, 19) points at 12 months (p < 0.01). Consistent with WOMAC and VAS values, motion ranges remained unaltered in the control group but improved at 12 months with BM-MSCs. X-ray revealed a reduction of the knee joint space width in the control group that was not seen in BM-MSCs high-dose group. MRI (WORMS protocol) showed that joint damage decreased only in the BM-MSC high-dose group, albeit slightly. CONCLUSIONS: The single intraarticular injection of in vitro expanded autologous BM-MSCs together with HA is a safe and feasible procedure that results in a clinical and functional improvement of knee OA, especially when 100 × 10(6) cells are administered. These results pave the way for a future phase III clinical trial. CLINICAL TRIALS: gov identifier NCT02123368. Nº EudraCT: 2009-017624-72.


Assuntos
Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/farmacologia , Transplante de Células-Tronco Mesenquimais , Osteoartrite do Joelho/terapia , Idoso , Terapia Combinada , Demografia , Feminino , Humanos , Ácido Hialurônico/efeitos adversos , Injeções Intra-Articulares , Imageamento por Ressonância Magnética , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/fisiopatologia , Amplitude de Movimento Articular/efeitos dos fármacos , Resultado do Tratamento , Escala Visual Analógica
10.
Ann Hepatol ; 13(5): 541-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25152987

RESUMO

BACKGROUND: Bacterial infections are frequent complications in patients with cirrhosis. Since they are associated with poor outcomes, antibiotics are frequently over-prescribed. Surrogate markers of bacterial infections, like procalcitonin, are needed to better discriminate between infected and not infected patients. AIMS: To evaluated the diagnostic accuracy of an ultra-sensitive procalcitonin assay for the diagnosis of bacterial infections in patients with cirrhosis. MATERIAL AND METHODS: In a single-center prospective study, we determined the basal levels of procalcitonin in 106 episodes of admissions to the emergency department in 84 cirrhotic patients. Patients were classified as infected or not infected by two independent hepatologists blinded to the procalcitonin result. RESULTS: The prevalence of bacterial infection was 28% (29 episodes). The median procalcitonin was significantly higher in the infected group than in the not infected group (0.45 vs. 0.061 ng/mL, p < 0.001). The diagnostic accuracy of procalcitonin for bacterial infection estimated by the ROC curve was 0.95 (CI: 95%, 0.91-0.99). When selecting a cutoff value of 0.098 ng/mL a sensitivity of 97% and a negative predictive value 98% were found. CONCLUSIONS: The use of an ultra-sensitive procalcitonin assay identifies patients with cirrhosis at very low risk of bacterial infections.


Assuntos
Infecções Bacterianas/microbiologia , Calcitonina/sangue , Cirrose Hepática/complicações , Precursores de Proteínas/sangue , Idoso , Antibacterianos/uso terapêutico , Área Sob a Curva , Argentina/epidemiologia , Infecções Bacterianas/sangue , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Biomarcadores/sangue , Peptídeo Relacionado com Gene de Calcitonina , Feminino , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Curva ROC , Fatores de Risco , Regulação para Cima
11.
J Bone Joint Surg Am ; 96(13): 1109-1117, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24990976

RESUMO

BACKGROUND: The use of autologous chondrocytes in cartilage repair is limited because of loss of the cartilage phenotype during expansion. The mechanosensing capacity of chondrocytes suggests evaluating the use of soft substrates for in vitro expansion. Our aim was to test the expansion of chondrocytes on collagen hydrogels to improve their capacity for chondrogenesis after a number of passages. METHODS: Rat cartilage cells were expanded on collagen hydrogels and on plastic, and the preservation of their chondrogenic capacity was tested both in vitro and in vivo. The expression of relevant markers during expansion on each surface was measured by real-time PCR (polymerase chain reaction). Expanded cells were then implanted in focal lesions in the medial femoral condyle of healthy sheep, and the newly formed tissue was analyzed by histomorphometry. RESULTS: Compared with cells cultured on plastic, cells cultured on hydrogels had better maintenance of the expression of the Sox9, Col2 (type-II collagen), FGFR3, and Alk-5 genes and decreased expression of Alk-1 and BMP-2. Pellets also showed increased expression of the cartilage marker genes aggrecan, Sox9, and Col2, and decreased expression of Col1 and Col10 (type-I and type-X collagen). ELISA (enzyme-linked immunosorbent assay) also showed a higher ratio of type-II to type-I collagen in pellets formed from cells expanded on hydrogels. When sheep chondrocytes were expanded and implanted in cartilage lesions in the femoral condyle of healthy sheep, hydrogel-expanded cells produced histologically better tissue compared with plastic-expanded cells. CONCLUSIONS: The expansion of chondrocytes on collagen hydrogels yielded cells with an improved chondrogenic capacity compared with cells expanded on plastic. CLINICAL RELEVANCE: The study results favor the use of hydrogel-expanded cells over the traditional plastic-expanded cells for autologous chondrocyte implantation.


Assuntos
Cartilagem Articular/citologia , Técnicas de Cultura de Células/métodos , Condrócitos/citologia , Condrogênese/fisiologia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Animais , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Articulação do Joelho , Plásticos , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Ovinos
12.
Knee Surg Sports Traumatol Arthrosc ; 22(11): 2771-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24051508

RESUMO

PURPOSE: Patellar tendon rupture after total knee replacement is a rare and highly limiting injury with multifactorial aetiology. Many reconstruction techniques have been described with not very predictable results. The use of allografts has been accepted as a suitable solution. METHODS: A series of seven patients with patellar tendon rupture treated with fresh-frozen tendon allograft reconstruction after knee arthroplasty is presented. RESULTS: Median follow-up is 25 months (20-31). Functional assessment improved, and the knee society score and knee functional score improved from 26 and 16 to 82 and 55, respectively. Median extension lag was 5° (0°-20°), with a median range of motion of 95° (70-100). Radiological study showed a rise of the patella of 22.26 mm. CONCLUSION: The use of fresh-frozen allografts as a solution to patellar tendon ruptures after knee arthroplasty seems to provide acceptable results. Increased patellar height does not seem to affect functionality. LEVEL OF EVIDENCE: Case series, Level IV.


Assuntos
Artroplastia do Joelho/efeitos adversos , Ligamento Patelar/lesões , Tendões/transplante , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Traumatismos do Joelho/etiologia , Traumatismos do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Procedimentos de Cirurgia Plástica , Recuperação de Função Fisiológica , Ruptura , Traumatismos dos Tendões/etiologia , Traumatismos dos Tendões/cirurgia , Transplante Homólogo
13.
Psychol Addict Behav ; 27(3): 841-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24059835

RESUMO

There is persistent disagreement over the degree of control that addicted patients are inferred to exercise over their drug use behavior. The study presented here proposes to investigate the perceptions and expectancies of controlled drug use in cocaine-addicted patients along the motivational stages that comprise their process of change. A total of 142 cocaine-addicted patients were evaluated with an original questionnaire--the Addictive Control Belief Inventory (ACBI)--and other validated inventories. The results were statistically analyzed. The precontemplative stage was characterized by the greatest perception of control over drug use, whereas maintenance showed the lowest perception of control. The results make it possible to infer a relation between awareness of the problematic aspects of drug use and a decrease in perceptions of controlled drug use.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/psicologia , Motivação , Autoeficácia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Autoimagem , Adulto Jovem
14.
Connect Tissue Res ; 54(3): 159-66, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23323769

RESUMO

AIM: The influence of culture substrate stiffness (in the kPa range) on chondrocyte behavior has been described. Here we describe the response to variations in substrate stiffness in a soft range (2-20 Pa), as it may play a role in understanding cartilage physiopathology. METHODS: We developed a system for cell culture in substrates with different elastic moduli using collagen hydrogels and evaluated chondrocytes after 2, 4, and 7 days in monolayer and three-dimensional (3D) cultures. Experiments were performed in normoxia and hypoxia in order to describe the effect of a low oxygen environment on chondrocytes. Finally, we also evaluated if dedifferentiated cells preserve the capacity for mechanosensing. RESULTS: Chondrocytes showed less proliferating activity when cultured in monolayer in the more compliant substrates. Expression of the cartilage markers Aggrecan (Acan), type II collagen (Col2a1), and Sox9 was upregulated in the less stiff gels (both in monolayer and in 3D culture). Stiffer gels induced an organization of the actin cytoskeleton that correlated with the loss of a chondrocyte phenotype. When cells were cultured in hypoxia, we observed changes in the cellular response that were mediated by HIF-1α. Results in 3D hypoxia cultures were opposite to those found in normoxia, but remained unchanged in monolayer hypoxic experiments. Similar results were found for dedifferentiated cells. CONCLUSIONS: Chondrocytes respond differently according to the stiffness of the substrate. This response depends greatly on the oxygen environment and on whether the chondrocyte is embedded or grown onto the hydrogel, since mechanosensing capacity was not lost with cell expansion.


Assuntos
Técnicas de Cultura de Células/métodos , Condrócitos/citologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Animais , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Forma Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Módulo de Elasticidade/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ovinos , Fatores de Tempo
15.
Knee Surg Sports Traumatol Arthrosc ; 21(8): 1737-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22864678

RESUMO

PURPOSE: Due to the attractive properties of poly(L-lactic acid) (PLLA) for tissue engineering, the aim was to determine the growth and differentiation capacity of mesenchymal stromal cells (MSCs) in PLLA scaffolds and their potential use in the treatment of cartilage diseases. METHODS: MSCs were cultured in PLLA films and thin porous membranes to study adherence and proliferation. Permeability and porosity were determined for the different scaffolds employed. The optimal conditions for cell seeding were first determined, as well as cell density and distribution inside the PLLA. Scaffolds were then maintained in expansion or chondrogenic differentiation media for 21 days. Apoptosis, proliferation and chondrogenic differentiation was assessed after 21 days in culture by immunohistochemistry. Mechanical characteristics of scaffolds were determined before and after cell seeding. RESULTS: MSCs uniformly adhered to PLLA films as well as to porous membranes. Proliferation was detected only in monolayers of pure PLLA, but was no longer detected after 10 days. Mechanical characterization of PLLA scaffolds showed differences in the apparent compression elastic modulus for the two sizes used. After determining high efficiencies of seeding, the production of extracellular matrix (ECM) was determined and contained aggrecan and collagens type I and X. ECM produced by the cells induced a twofold increase in the apparent elastic modulus of the composite. CONCLUSIONS: Biocompatible PLLA scaffolds have been developed that can be efficiently loaded with MSCs. The scaffold supports chondrogenic differentiation and ECM deposition that improves the mechanics of the scaffold. Although this improvement does not met the expectations of a hyaline-like cartilage ECM, in part due to the lack of a mechanical stimulation, their potential use in the treatment of cartilage pathologies encourages to improve the mechanical component.


Assuntos
Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Adulto , Agrecanas/metabolismo , Apoptose , Doenças das Cartilagens/terapia , Adesão Celular , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Colágeno Tipo I/metabolismo , Colágeno Tipo X/metabolismo , Matriz Extracelular/metabolismo , Humanos , Ácido Láctico , Microscopia Eletrônica de Varredura , Poliésteres , Polímeros
16.
J Am Soc Mass Spectrom ; 20(2): 287-94, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19013080

RESUMO

We determine the sensitivity of several commercial atmospheric pressure ionization mass spectrometers towards ambient vapors, ionized by contact with an electrospray of acidified or ammoniated solvent, a technique often referred to as secondary electrospray ionization (SESI). Although a record limit of detection of 0.2 x 10(-12) atmospheres (0.2 ppt) is found for explosives such as PETN and 0.4 ppt for TNT (without preconcentration), this still implies the need for some 10(8)-10(9) vapor molecules/s for positive identification of explosives. This extremely inefficient use of sample is partly due to low charging probability ( approximately 10(-4)), finite ion transmission, and counting probability in the mass spectrometer (1/10 in quadrupoles), and a variable combination of duty cycle and background noise responsible typically for a 10(3) factor loss of useful signal.


Assuntos
Substâncias Explosivas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Pressão Atmosférica , Tetranitrato de Pentaeritritol/análise , Trinitrotolueno/análise , Incerteza
17.
Arthroscopy ; 19(8): 833-41, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14551545

RESUMO

PURPOSE: The purpose of this study was to analyze cartilage degeneration in knees after total medial meniscectomy, transplantation of fresh-frozen meniscus allograft, and Achilles tendon allograft. TYPE OF STUDY: Experimental study. METHODS: We have studied the articular cartilage in the medial compartment of the left knees in 32 sheep aged 5 to 6 months, with 8 animals in each group. The study was performed after meniscectomy (group I), transplantation of fresh-frozen meniscus allograft (group II), use of fresh-frozen Achilles tendon allograft (group III), and in a control group (group IV). For the histologic study, all samples were stained with Masson's trichrome and Safranine-O. Mankin's score was applied to grade the histologic damage to the articular cartilage. RESULTS: The group with the greatest number of degenerative changes was group III, followed by groups I and II. The percentage of thickness of cartilage detected by Safranine-O stain was found to be significantly different in both tibia and femur between the control group and the other 3 groups, but not among groups I, II, and III. The immunoreactivity of the articular surfaces in tibia and femur showed notable differences in all the groups. Collagen X was present in the degenerative hypertrophic chondrocytes in the damaged articular surfaces. CONCLUSIONS: Meniscal replacement with meniscal and Achilles tendon allografts provides partial protection against articular damage after a meniscectomy.


Assuntos
Tendão do Calcâneo/transplante , Cartilagem Articular/patologia , Meniscos Tibiais/cirurgia , Complicações Pós-Operatórias/patologia , Tendão do Calcâneo/química , Tendão do Calcâneo/patologia , Animais , Cartilagem Articular/química , Cartilagem Articular/diagnóstico por imagem , Colágeno Tipo II/análise , Colágeno Tipo X/análise , Ligamentos Colaterais/cirurgia , Criopreservação , Radiografia , Ovinos , Transplante Homólogo , Cicatrização
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