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1.
Dermatol Surg ; 44(5): 721-725, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29315143

RESUMO

BACKGROUND: Botulinum-derived neurotoxins have become a substantial tool in dermatologists' armamentarium for facial/neck rejuvenation. Current literature discusses anatomical "danger zones" to avoid during neurotoxin injection to prevent brow ptosis, blepharoptosis, and lower facial ptosis. OBJECTIVE: The aim of this study was to determine whether lidocaine 1% local anesthetic can be used to predict botulinum toxin treatment outcomes and prevent adverse effects of unwanted paralysis. MATERIALS AND METHODS: One percent lidocaine was drawn up using BD ultra-fine 31 G (5/16″), 0.5-mL insulin syringes in the same quantity that would be drawn up for neurotoxin placement. The patient's face was cleansed and mapped; 0.1 mL of 1% lidocaine was injected × 5 sites in the glabella; and 3 sites were injected with 0.05 mL in the frontalis. The patient was assessed after 10 minutes. RESULTS: Improvement in frontalis and glabellar rhytides was appreciated, with noted "spocking" of the lateral brows. This technique allowed the authors to visualize the need for placement of toxin more laterally with eventual successful predictive placement for neurotoxin. CONCLUSION: This technique of using local 1% lidocaine allows the practitioner to devise a neurotoxin distribution map tailored for each patient to limit unwanted paralysis from improper neurotoxin placement.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Neurotoxinas/administração & dosagem , Rejuvenescimento , Envelhecimento da Pele/efeitos dos fármacos , Adulto , Anestésicos Locais/administração & dosagem , Toxinas Botulínicas Tipo A/efeitos adversos , Técnicas Cosméticas , Face , Humanos , Injeções Intradérmicas , Lidocaína/administração & dosagem , Masculino , Pescoço , Neurotoxinas/efeitos adversos , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Resultado do Tratamento
4.
JAMA Dermatol ; 153(6): 575-577, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28403392

RESUMO

Importance: Minor bleeding is the most common complication of dermatologic surgery. Topical brimonidine, 0.33%, gel has been reported for the use of hemostasis in dermatologic surgery. The safety profile and risk of systemic toxic effects when brimonidine is used topically for hemostasis is unknown. Objective: To determine the risk of systemic toxic effects of topical brimonidine, 0.33%, gel when used for hemostasis. Design, Setting, and Participants: In this case series from a private practice (Hollywood Dermatology), 2 patients presented for dermatologic procedures, complicated by persistent bleeding. Interventions: Patients were treated with 10 g of brimonidine, 0.33%, gel applied under occlusion for hemostasis. Main Outcomes and Measures: Mental status, cardiopulmonary function. Results: Both patients experienced deterioration of mental status, respiratory depression, and somnolence. Results from cardiac testing, laboratory workup, and imaging were negative for cardiac or neurologic etiology. Both patients improved in less than 24 hours. Conclusions and Relevance: Topical brimonidine, 0.33%, gel can result in systemic central nervous system toxic effects when used as a hemostatic agent. At present, it is not possible to define a quantity with which brimonidine can be used safely, nor can a safe wound size be defined. We, therefore, urge against the use of topical brimonidine as a hemostatic agent until its safety is further investigated.


Assuntos
Tartarato de Brimonidina/efeitos adversos , Hemostáticos/efeitos adversos , Transtornos Mentais/induzido quimicamente , Administração Cutânea , Idoso , Idoso de 80 Anos ou mais , Tartarato de Brimonidina/administração & dosagem , Distúrbios do Sono por Sonolência Excessiva/induzido quimicamente , Géis , Hemostáticos/administração & dosagem , Humanos , Masculino , Insuficiência Respiratória/induzido quimicamente
5.
Clin Dermatol ; 34(3): 383-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27265077

RESUMO

Polymorphic eruption of pregnancy (PEP), a specific dermatosis of pregnancy also known as pruritic urticarial papules and plaques of pregnancy (PUPPP), is a benign, self-limited skin disorder. Key features include an increased prevalence in primigravidas, onset in the third trimester, remission near the time of delivery, and association with multiple gestation pregnancy. The clinical features are crucial to diagnosis. Histopathology is nonspecific, and immunofluorescence studies help differentiate PEP from pemphigoid gestationis. The pathogenesis of PEP remains elusive, and relevant theories are reviewed. There are no associated maternal or fetal risks, and treatment is largely symptomatic.


Assuntos
Complicações na Gravidez/diagnóstico , Complicações na Gravidez/etiologia , Prurido/diagnóstico , Prurido/etiologia , Feminino , Número de Gestações , Humanos , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/terapia , Gravidez Múltipla , Prognóstico , Prurido/epidemiologia , Prurido/terapia , Fatores Sexuais
9.
Tissue Eng Part A ; 21(3-4): 683-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25315796

RESUMO

Current approaches to cartilage tissue engineering require a large number of chondrocytes. Although chondrocyte numbers can be expanded in monolayer culture, the cells dedifferentiate and unless they can be redifferentiated are not optimal to use for cartilage repair. We took advantage of the differential effect of culture conditions on the ability of passaged and primary chondrocytes to form cartilage tissue to dissect out the extracellular matrix (ECM) molecules produced and accumulated in the early stages of passaged cell cartilage tissue formation as we hypothesized that passaged bovine cells that form cartilage accumulate a pericellular matrix that differs from cells that do not form cartilage. Twice passaged bovine chondrocytes (P2) (cartilage forming), or as a control primary chondrocytes (P0) (which do not generate cartilage), were cultured on three-dimensional membrane inserts in serum-free media. P2 redifferentiation was occurring during the first 8 days as indicated by increased expression of the chondrogenic genes Sox9, collagen type II, aggrecan, and COMP, suggesting that this is an appropriate time period to examine the ECM. Mass spectrometry showed that the P2 secretome (molecules released into the media) at 1 week had higher levels of collagen types I, III, and XII, and versican while type II collagen and COMP were found at higher levels in the P0 secretome. There was increased collagen synthesis and retention by P2 cells compared to P0 cells as early as 3 days of culture. Confocal microscopy showed that types XII, III, and II collagen, aggrecan, versican, and decorin were present in the ECM of P2 cells. In contrast, collagen types I, II, and III, aggrecan, and decorin were present in the ECM of P0 cells. As primary chondrocytes grown in serum-containing media, a condition that allows for the generation of cartilage tissue in vitro, also accumulate versican and collagen XII, this study suggests that these molecules may be necessary to provide a microenvironment that supports hyaline cartilage formation. Further study is required to determine if these molecules are also accumulated by passaged human chondrocytes and their role in promoting hyaline cartilage formation.


Assuntos
Cartilagem/citologia , Cartilagem/crescimento & desenvolvimento , Condrócitos/citologia , Condrócitos/fisiologia , Colágeno Tipo XII/metabolismo , Versicanas/fisiologia , Animais , Técnicas de Cultura Celular por Lotes/métodos , Bovinos , Diferenciação Celular/fisiologia , Células Cultivadas , Condrogênese/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Engenharia Tecidual/métodos
10.
Tissue Eng Part A ; 20(15-16): 2224-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24606204

RESUMO

OBJECTIVE: One of the factors preventing clinical application of regenerative medicine to degenerative cartilage diseases is a suitable source of cells. Chondrocytes, the only cell type of cartilage, grown in vitro under culture conditions to expand cell numbers lose their phenotype along with the ability to generate hyaline cartilaginous tissue. In this study we determine that a serum- and growth-factor-free three-dimensional (3D) culture system restores the ability of the passaged chondrocytes to form cartilage tissue in vitro, a process that involves sox9. METHODS: Bovine articular chondrocytes were passaged twice to allow for cell number expansion (P2) and cultured at high density on 3D collagen-type-II-coated membranes in high glucose content media supplemented with insulin and dexamethasone (SF3D). The cells were characterized after monolayer expansion and following 3D culture by flow cytometry, gene expression, and histology. The early changes in signaling transduction pathways during redifferentiation were characterized. RESULTS: The P2 cells showed a progenitor-like antigen profile of 99% CD44(+) and 40% CD105(+) and a gene expression profile suggestive of interzone cells. P2 in SF3D expressed chondrogenic genes and accumulated extracellular matrix. Downregulating insulin receptor (IR) with HNMPA-(AM3) or the PI-3/AKT kinase pathway (activated by insulin treatment) with Wortmannin inhibited collagen synthesis. HNMPA-(AM3) reduced expression of Col2, Col11, and IR genes as well as Sox6 and -9. Co-immunoprecipitation and chromatin immunoprecipitation analyses of HNMPA-(AM3)-treated cells showed binding of the coactivators Sox6 and Med12 with Sox9 but reduced Sox9-Col2a1 binding. CONCLUSIONS: We describe a novel culture method that allows for increase in the number of chondrocytes and promotes hyaline-like cartilage tissue formation in part by insulin-mediated Sox9-Col2a1 binding. The suitability of the tissue generated via this approach for use in joint repair needs to be examined in vivo.


Assuntos
Cartilagem Articular/crescimento & desenvolvimento , Cartilagem Articular/metabolismo , Técnicas de Cultura de Células/métodos , Condrogênese , Colágeno Tipo II/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Fatores de Transcrição SOX9/metabolismo , Animais , Cartilagem Articular/citologia , Bovinos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/citologia , Condrogênese/efeitos dos fármacos , Meios de Cultura Livres de Soro , Dexametasona/farmacologia , Insulina/metabolismo , Fenótipo , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Clin J Sport Med ; 24(1): 31-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24231930

RESUMO

OBJECTIVE: Using systematic review methodology, we endeavored to answer the following questions concerning the treatment of osteochondral pathology: (1) what pathologies have been treated in vivo with the use of platelet-rich plasma (PRP); (2) what methods of PRP preparation and delivery have been reported; (3) what assessment tools and comparison group have been used to assess its effectiveness; and (4) what are the clinical outcomes of its use. DATA SOURCES: A systematic literature search was performed of the OVID, EMBASE, and Evidence Based Medicine Reviews databases to identify all studies published up to October 2012 that assessed clinical outcomes of the use of PRP for the treatment of chondral and osteochondral pathology, excluding those including concomitant management of acute fractures or ligament reconstruction. DATA EXTRACTION: The included studies were reviewed and the following data were extracted and tabulated: study authors' year and journal, study design and level of evidence, pathology treated, methods of PRP preparation and delivery, and clinical outcome scores. DATA SYNTHESIS: Ten studies were included in the final analysis. The majority of studies assessed the use of PRP in the treatment of degenerative osteoarthritis of the knee or hip (representing 570 of a total of 662 joints). The majority of patients were treated with intra-articular injections, whereas 2 studies used PRP as an adjunct to surgical treatment. Significant improvements in joint-specific clinical scores (7 of 8 studies), general health scores (4 of 4 studies), and pain scores (4 of 6 studies) compared with baseline were reported up to 6-month follow-up, but few studies provided longer-term data. No studies reported worse scores compared with baseline at final follow-up. Three of 4 comparative studies reported significantly better clinical and/or pain scores when compared with hyaluronic acid injections at similar follow-up times. CONCLUSIONS: Currently, there is a paucity of data supporting the use of PRP for the management of focal traumatic osteochondral defects. There is limited evidence suggesting short-term clinical benefits with the use of PRP for symptomatic osteoarthritis of the knee, but the studies published to date are of poor quality and at high risk for bias. Further high-quality comparative studies with longer follow-up are needed to ascertain whether PRP is beneficial, either alone or as an adjunct to surgical procedures, in the management of articular cartilage pathology.


Assuntos
Traumatismos do Joelho/terapia , Osteoartrite do Joelho/terapia , Plasma Rico em Plaquetas , Cartilagem Articular/lesões , Humanos , Osteoartrite do Quadril/terapia , Resultado do Tratamento
12.
Am J Orthop (Belle Mead NJ) ; 42(2): 78-82, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23431551

RESUMO

We report our experience with the use of fresh glenoid osteochondral allograft in the treatment of a chronic posttraumatic posterior subluxation of the shoulder associated with glenoid bone loss in a 54-year-old recreational football player. Based on the pathoanatomy of the lesion and availability of a bone bank providing fresh allograft, we opted for an open anatomic reconstruction using a fresh glenoid allograft. A posterior approach was used; the prepared allograft was placed in the appropriate anatomic position and fixed with 2 small fragment screws with washers. At 2-year follow-up, the clinical outcome is excellent. This procedure may represent an effective option for the treatment of chronic posterior shoulder instability due to glenoid bone loss. However, the long-term efficacy and the progression of glenohumeral osteoarthritis need to be evaluated.


Assuntos
Reabsorção Óssea/cirurgia , Instabilidade Articular/cirurgia , Luxação do Ombro/cirurgia , Articulação do Ombro/cirurgia , Transplante Ósseo , Humanos , Instabilidade Articular/diagnóstico , Masculino , Pessoa de Meia-Idade , Luxação do Ombro/diagnóstico , Transplante Homólogo
13.
J Histochem Cytochem ; 60(8): 576-87, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22610463

RESUMO

To circumvent the problem of a sufficient number of cells for cartilage engineering, the authors previously developed a two-stage culture system to redifferentiate monolayer culture-expanded dedifferentiated human articular chondrocytes by co-culture with primary bovine chondrocytes (bP0). The aim of this study was to analyze the composition of the cartilage tissue formed in stage 1 and compare it with bP0 grown alone to determine the optimal length of the co-culture stage of the system. Biochemical data show that extracellular matrix accumulation was evident after 2 weeks of co-culture, which was 1 week behind the bP0 control culture. By 3 to 4 weeks, the amounts of accumulated proteoglycans and collagens were comparable. Expression of chondrogenic genes, Sox 9, aggrecan, and collagen type II, was also at similar levels by week 3 of culture. Immunohistochemical staining of both co-culture and control tissues showed accumulation of type II collagen, aggrecan, biglycan, decorin, and chondroitin sulfate in appropriate zonal distributions. These data indicate that co-cultured cells form cartilaginous tissue that starts to resemble that formed by bP0 after 3 weeks, suggesting that the optimal time to terminate the co-culture stage, isolate the now redifferentiated cells, and start stage 2 is just after 3 weeks.


Assuntos
Cartilagem Articular/citologia , Condrócitos/citologia , Engenharia Tecidual , Animais , Cartilagem Articular/metabolismo , Cartilagem Articular/ultraestrutura , Bovinos , Condrócitos/metabolismo , Técnicas de Cocultura , Colágeno/metabolismo , Feminino , Humanos , Proteoglicanas/metabolismo , Fatores de Tempo
14.
J Pediatr Orthop B ; 21(3): 235-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21946869

RESUMO

Down Syndrome can result in musculoskeletal abnormalities of the hip at an early age. Avascular necrosis of the femoral head can occur as a result of slipped capital femoral epiphysis causing the patient a great deal of pain, limiting the ability to ambulate. Despite the benefits that this patient group can receive from the surgery, surgeons may be apprehensive to operate. It is our experience that these patients benefit greatly from arthroplasty without complication. In this report, we present a total hip replacement to treat avascular necrosis in an adolescent and address the concerns that surgeons may have in treating this patient population.


Assuntos
Artroplastia de Quadril/métodos , Síndrome de Down/cirurgia , Necrose da Cabeça do Fêmur/cirurgia , Luxação do Quadril/cirurgia , Osteotomia/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Atividades Cotidianas , Adolescente , Síndrome de Down/complicações , Síndrome de Down/patologia , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/patologia , Luxação do Quadril/etiologia , Humanos , Masculino , Qualidade de Vida , Recuperação de Função Fisiológica , Escorregamento das Epífises Proximais do Fêmur/etiologia , Escorregamento das Epífises Proximais do Fêmur/patologia , Escorregamento das Epífises Proximais do Fêmur/cirurgia , Falha de Tratamento , Resultado do Tratamento
15.
Clin J Sport Med ; 21(4): 344-52, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21562414

RESUMO

OBJECTIVE: To evaluate, through a systematic review of the current literature, the evidence-based outcomes of the use of platelet-rich plasma (PRP) for the treatment of tendon and ligament injuries. DATA SOURCES: A search of English-language articles was performed in PubMed and EMBASE using keywords "PRP," "platelet plasma," and "platelet concentrate" combined with "tendon" and then "ligament" independently. The search was conducted through September 2010. STUDY SELECTION: Search was limited to in vivo studies. Nonhuman studies were excluded. Tissue engineering strategies, which included a combination of PRP with additional cell types (bone marrow), were also excluded. Articles with all levels of evidence were included. Thirteen of 32 retrieved articles respected the inclusion criteria. DATA EXTRACTION: The authors reviewed and tabulated data according to the year of study and journal, study type and level of evidence, patient demographics, method of PRP preparation, site of application, and outcomes. DATA SYNTHESIS: The selected studies focused on the application of PRP in the treatment of patellar and elbow tendinosis, Achilles tendon injuries, rotator cuff repair, and anterior cruciate ligament (ACL) reconstruction. Seven studies demonstrated favorable outcomes in tendinopathies in terms of improved pain and functional scores. In 3 studies on the use of PRP in ACL reconstruction, no statistically significant differences were seen with regard to clinical outcomes, tunnel widening, and graft integration. One study examined the systemic effects after the local PRP application for patellar and elbow tendinosis. CONCLUSIONS: Presently, PRP use in tendon and ligament injuries has several potential advantages, including faster recovery and, possibly, a reduction in recurrence, with no adverse reactions described. However, only 3 randomized clinical trials have been conducted.


Assuntos
Ligamentos/lesões , Plasma Rico em Plaquetas , Traumatismos dos Tendões/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
16.
Int Orthop ; 35(5): 661-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20442995

RESUMO

Patients with Down's syndrome (DS) have an increased incidence of coxarthrosis which may become symptomatic with prolonged life expectancy. We present seven consecutive patients (nine hips) with DS who had primary total hip arthroplasty (THA). Average clinical and radiological follow-up was 9.9 ± 6.4 years (range 2-22.25). Harris hip scores (HHS) improved significantly (p < 0.01) from 41.1 (range 18.5-65) to 80.2 (range 67.5-91) at latest follow-up. Two patients required revision arthroplasty for stem loosening at 16 (osteolysis) and six years (trauma) following THA, respectively. Six of the THAs required a constrained liner. No dislocations or deep infections were encountered. We contend that THA is a reliable surgical intervention in patients with DS and may be performed in symptomatic patients.


Assuntos
Artroplastia de Quadril/métodos , Síndrome de Down/cirurgia , Osteoartrite do Quadril/cirurgia , Atividades Cotidianas , Adulto , Artroplastia de Quadril/instrumentação , Síndrome de Down/complicações , Nível de Saúde , Articulação do Quadril/fisiopatologia , Articulação do Quadril/cirurgia , Prótese de Quadril , Humanos , Pessoa de Meia-Idade , Osteoartrite do Quadril/complicações , Desenho de Prótese , Falha de Prótese , Amplitude de Movimento Articular , Reoperação , Resultado do Tratamento
17.
Mcgill J Med ; 13(1): 22, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22363180

RESUMO

Preserving the ability to maintain an active lifestyle is a major concern in the reconstruction of the knee in young patients. For the healthy individual who desires to maintain a relatively active lifestyle, fresh osteochondral allografts may serve as an alternative to total joint reconstruction. The use of fresh allografts is primarily indicated in the patient suffering from a traumatic loss of articular segments, who is too young or active for arthroplasty. In addition, fresh osteochondral allografts have a number of advantages over arthroplasty such as providing surgeons with a source of large grafts that can be fitted to replace osteochondral defects and cover the majority or entirety of articular surfaces without any donor site morbidity. In this case, a young, active patient lost a 7 x 8 cm portion of their distal femur, including a large portion of the articulating surface. Using a fresh osteochondral allograft, harvested within 24 hours of donor death, a segment was fitted to match bony apposition, articular congruity, and congruity with the femoral notch and affixed with four partially threaded cancellous screws. Joint function was restored with the allograft in place, allowing the patient to delay the need for a total joint replacement.

18.
Orthopedics ; 33(9): 629, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20839689

RESUMO

Hip osteoarthritis is prevalent in 8% to 28% of patients with Down syndrome. Presence of disabling hip pain is increased along with prolonged life expectancy, suggesting total hip arthroplasty (THA). Seven consecutive patients (9 hips) with Down syndrome underwent primary THA. Coxarthrosis was secondary to developmental hip dysplasia in 6 patients and slipped capital epiphysis in 1 patient. In 5 patients (7 hips), a previous hip surgery was performed. Average clinical and radiological follow-up was 9.9±6.4 years (range, 2-22.5 years; median, 9.3 years). Average patient age at THA was 34.8±7.5 years (range, 25- 47 years; median, 35.4 years). In 2 patients (3 hips), a trochanteric slide was used for the surgical approach, while a lateral transgluteal approach was used in the remaining patients. One-way analysis of variance test was used to compare Harris Hip Scores (HHS) at postoperative follow-up.Harris Hip Scores improved significantly (P=.008) from 4.1±15.1 (range, 18.5-65; median, 45) to 84.8.3±7.7 (range, 70-93; median, 85.8) at 4-year follow-up. Harris Hip Scores (average, 70.9±6.2; range, 66.5-80; median, 68) remained essentially unchanged (P=.43) at 8-year follow-up. Two patients required revision THA for stem loosening at 6 and 16 years post-THA, respectively. The first patient is 7 years post-revision and ambulates without aids. The second patient is 6.1 years post-revision and ambulates with a walker. Six of the THAs required a constrained liner. No dislocations or deep infections were encountered. At last follow-up, all patients had a functional range of motion without evidence of discomfort related to their THA.


Assuntos
Artroplastia de Quadril , Síndrome de Down/complicações , Osteoartrite do Quadril/cirurgia , Adulto , Seguimentos , Luxação Congênita de Quadril/complicações , Luxação Congênita de Quadril/etiologia , Humanos , Pessoa de Meia-Idade , Osteoartrite do Quadril/etiologia , Cooperação do Paciente , Reoperação , Resultado do Tratamento
19.
Tissue Eng Part A ; 16(2): 643-51, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19754222

RESUMO

Identifying a source of sufficient numbers of chondrocytes for cartilage tissue engineering is a major factor limiting its use clinically. Previously we demonstrated that combined coculture of passaged dedifferentiated articular chondrocytes with primary bovine chondrocytes will induce their redifferentiation. In this study we determine whether these two cell types have to be in contact, whether human chondrocytes respond similarly, and whether the ability of primary cells to influence passaged cells depends on the age of the donor. Coculture of primary and passaged bovine chondrocytes grown on filter inserts placed in the same culture well but not in direct contact resulted in the passaged cells accumulating matrix rich in proteoglycans and type II collagen. There was upregulation of type II collagen and Sox9 and decrease in type I collagen gene expression in the passaged cells, to levels not significantly different from those of primary chondrocytes. Passaged chondrocytes obtained from older animals responded similarly to cells from younger animals. Further, passaged human chondrocytes were also induced to form cartilage tissue when placed in side-by-side culture with bovine chondrocytes; these data suggest that a soluble factor(s) may be responsible for redifferentiation of passaged chondrocytes and that it is not species specific. The responsiveness of human chondrocytes to this factor(s) suggests that this approach may be suitable to overcome the problem of limited chondrocyte numbers for cartilage tissue engineering.


Assuntos
Técnicas de Cultura de Células/métodos , Condrócitos/citologia , Condrócitos/metabolismo , Colágeno/metabolismo , Proteoglicanas/metabolismo , Animais , Bovinos , Diferenciação Celular/genética , Células Cultivadas , Condrogênese/genética , Técnicas de Cocultura , DNA/metabolismo , Regulação da Expressão Gênica , Humanos , Solubilidade , Fatores de Tempo , Engenharia Tecidual
20.
J Tissue Eng Regen Med ; 4(3): 233-41, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19998328

RESUMO

A source of sufficient number of cells is a major limiting factor for cartilage tissue engineering. To circumvent this problem, we developed a co-culture method to induce redifferentiation in bovine articular chondrocytes, which had undergone dedifferentiation following serial passage in monolayer culture. In this study we determine whether human osteoarthritic (OA) and non-diseased passaged dedifferentiated chondrocytes will respond similarly. Human passaged chondrocytes were co-cultured for 4 weeks with primary bovine chondrocytes and their redifferentiation status was determined. Afterwards the cells were cultured either independently or in co-culture with cryopreserved passaged cells for functional analysis. The co-culture of passaged cells with primary chondrocytes resulted in reversion of their phenotype towards articular chondrocytes, as shown by increased gene expression of type II collagen and COMP, decreased type I collagen expression and extracellular matrix formation in vitro. Furthermore, this redifferentiation was stable, as those cells not only formed hyaline-like cartilage tissue when grown on their own but also they could induce redifferentiation of passaged chondrocytes in co-culture. These data suggest that it may be possible to use autologous chondrocytes obtained from osteoarthritic cartilage to form tissue suitable to use for cartilage repair.


Assuntos
Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Animais , Bovinos , Diferenciação Celular , Condrócitos/citologia , Técnicas de Cocultura , Humanos , Imuno-Histoquímica , Osteoartrite/metabolismo , Osteoartrite/patologia , Reação em Cadeia da Polimerase
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