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1.
Microbiol Spectr ; 12(4): e0392723, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38441470

RESUMO

Aeromonas hydrophila, an aquatic pathogenic bacterium, has been found to infect many fish species and cause huge aquaculture losses. Antibiotics are the most common drugs used to treat these infections. However, antibiotic abuse can lead to the development of antibiotic resistance. Probiotics have the potential to replace antibiotics for preventing infections. Zebrafish (Danio rerio) is a model organism used to study the innate immune system and host-pathogen interactions. Currently, there is little information on how the fish immune system responds to A. hydrophila and probiotic treatment. To increase the understanding of the molecular mechanisms behind the zebrafish defense against A. hydrophila and provide evidence that antibiotics can be replaced by probiotics, a transcriptome analysis of the zebrafish spleen was conducted 48 hours after infection by A. hydrophila, as well as after treatment using Lactococcus lactis KUST48 4 hours after infection. A total of 36,499 genes were obtained. There were 3,337 genes found to have significant differential expression between treatment and control groups. According to further annotation and enrichment analysis, differentially expressed genes (DEGs) were involved in signal transduction, endocrine system cancer, and the immune system. Insulin resistance disappeared in the zebrafish after treatment. Quantitative real-time PCR was performed to confirm the significant regulation of immune defense DEGs, the results of which were consistent with the RNA-sequencing data. These results could serve as a basis for future studies on the immune response to A. hydrophila and provide suggestions for probiotic alternatives to antibiotics, which will be of great significance to aquaculture and environmental protection.IMPORTANCEIn recent years, the unreasonable use of antibiotics has led to the emergence of drug-resistant pathogenic bacteria, antibiotic residues, cross infection, toxic side effects, and so on, which has caused a serious threat to human food safety and life health. In recent years, many studies have demonstrated the potential of probiotics as a substitute for antibiotics, but there is still a lack of understanding of the molecular mechanisms underlying probiotic therapy. We conduct a research on the impact of Lactococcus lactis KUST48 on the transcription profile of Aeromonas hydrophila-infected zebrafish spleen. Mortality of zebrafish infected with A. hydrophila was significantly reduced after treatment with L. lactis KUST48. Our results can help to strengthen our understanding of the pathogenic mechanisms of zebrafish and provide a valuable reference for the molecular mechanisms of probiotic therapy.


Assuntos
Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Lactococcus lactis , Animais , Humanos , Peixe-Zebra , Aeromonas hydrophila/genética , Lactococcus lactis/genética , Baço , Antibacterianos , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Negativas/microbiologia , Doenças dos Peixes/microbiologia
2.
Biomater Sci ; 10(23): 6818-6827, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36317498

RESUMO

In this study, a type of biodegradable multi-hollow iron phosphate (FeP) with excellent Fenton reaction ability and doxorubicin (DOX) loading capacity is synthesized in one-pot. This hollow FeP with complex interior not only affords high drug loading efficiency, but also obviates DOX leakage in normal tissues. In order to inhibit the formation of inert Fe(OH)x and endow the nanoplatform with a highly hydrophilic surface, PEG was anchored to it with a dopamine linkage, which formed an Fe chelating complex. DOX-loaded FeP modified with PEG could be disintegrated when responding to the lysosomal acid environment, releasing both ferric and ferrous ions as well as DOX. Therefore, apart from chemotherapy with DOX, the continuously generated iron ions catalyze a fast Fenton reaction with the innate H2O2 in tumor cells and produce abundant highly toxic hydroxyl radicals for nanocatalytic tumor therapy. Taken together, we believe that this nanoplatform will significantly advance the fields of both Fe-based nanomaterials and nanocatalytic tumor therapy.


Assuntos
Nanopartículas , Nanopartículas/uso terapêutico , Peróxido de Hidrogênio , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ferro , Fosfatos , Linhagem Celular Tumoral
3.
Biomater Sci ; 8(5): 1431-1441, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-31960005

RESUMO

Novel Janus nanoparticles (J-NPs) are developed by using single iron oxide (Fe3O4) nanoparticles as the core and hydrophobic/hydrophilic polymeric brushes as the cloak. Because of the superparamagnetism and asymmetric functionality of J-NPs, they are used as drug carriers and therapeutic agents for cancer chemotherapy and magnetic hyperthermia with a magnetic resonance imaging (MRI) guide. The asymmetric functionality is constituted of hydrophobic polymethyl methacrylate (PMMA) brushes and hydrophilic polyacrylic acid (PAA) brushes, which are 'grafting to' or 'grafting from' Fe3O4 nanoparticles via activators regenerated by electron transfer atom transfer radical polymerization. The terminal chains of PMMA and PAA brushes are coordinated with Fe3O4 nanoparticles, so PMMA/Fe3O4/PAA J-NPs possess structural stability in solvents. Because of the brush-structure, PMMA/Fe3O4/PAA J-NPs show high encapsulation efficiency (89.75 ± 2.35%) and loading capacity (8.95 ± 0.26%). Under the alternating magnetic field (AMF), drug-loaded J-NPs achieve the highest cell proliferation-inhibition ratio in the cell proliferation test in vitro and the tumor growth inhibition test in vivo compared to single chemotherapy or magnetic hyperthermia. Meanwhile, J-NPs show good T2 imaging.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/terapia , Hipertermia Induzida , Nanopartículas de Magnetita/química , Polímeros/química , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/química , Neoplasias da Mama/diagnóstico por imagem , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Interações Hidrofóbicas e Hidrofílicas , Campos Magnéticos , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Células NIH 3T3 , Tamanho da Partícula , Polímeros/síntese química , Propriedades de Superfície
4.
BMC Public Health ; 19(1): 808, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234809

RESUMO

BACKGROUND: Sleep problems are common in the general population. Cigarette smoking is common in the general population of China. Examinations of the prevalence of poor sleep quality among Chinese smokers and nonsmokers are still lacking. This study was designed to examine sleep quality and sleep disturbances among cigarette smokers and nonsmokers in the general population in central China. METHODS: In this population-based sampling project, we used a multi-stage sampling method to recruit survey participants from September 2012 to October 2012 in rural and urban areas of Hunan province, China. A total of 27,300 subjects were sampled from the general population and 26,282 completed the self-report of cigarette smoking characteristics. Cigarette smoker was defined as having smoked ≥100 cigarette in a lifetime and smoked during the last 28 days. Cigarette smoking characteristics were obtained from smokers, including cigarettes per day, years of smoking, quit attempts, and smoking cravings. The Pittsburgh Sleep Quality Index (PSQI) was applied to assess quality of sleep and sleep disturbances (PSQI score > 5). RESULTS: Significantly more smokers than nonsmokers demonstrated poor sleep quality and sleep disturbances. Among smokers, linear regression analyses showed that poor sleep was inversely associated with cigarettes per day, and positively associated with years of smoking, quit attempts, and smoking craving. Logistic regression analysis showed that quit attempts and smoking cravings were associated with higher odds of sleep disturbances. CONCLUSIONS: Sleep disturbances were more prevalent among cigarette smokers than nonsmokers. Smokers also varied in sleep problems on the basis of the characteristics of their smoking. Smokers should be informed about the link between cigarette smoking and poor sleep quality, and should be advised that one of several important health benefits from smoking cessation could be the improvement of sleep quality. Sleep therapy should be recommended as an adjunctive treatment for smoking cessation.


Assuntos
Fumar Cigarros/efeitos adversos , não Fumantes/estatística & dados numéricos , Transtornos do Sono-Vigília/epidemiologia , Fumantes/estatística & dados numéricos , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , População Rural/estatística & dados numéricos , Sono , Transtornos do Sono-Vigília/etiologia , Inquéritos e Questionários , População Urbana/estatística & dados numéricos
5.
J Biomed Nanotechnol ; 15(2): 215-416, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30596546

RESUMO

Due to the special magnetic performance and nano-size, superparamagnetic iron oxide nanoparticles (SPIOs) have been extensively investigated in cancer diagnosis and therapy, such as magnetic resonance imaging (MRI), drug delivery, magnetic hyperthermia treatment, and so on. The development of nanomedicine brings challenges and innovations to magnetic materials, multifunction and integration become a kind of trend for material designs. Recent studies show that cancer-targeted MRI and drug delivery, or MRI-guided drug delivery and magnetic hyperthermia treatment in vivo, external magnetic field guided MRI, drug delivery and magnetic hyperthermia treatment in vitro, had become the research hotpots. This account presents a review on the recent progresses of SPIOs' applications in cancer diagnosis and therapy.


Assuntos
Nanopartículas de Magnetita , Neoplasias , Sistemas de Liberação de Medicamentos , Humanos , Imageamento por Ressonância Magnética , Nanomedicina
6.
Schizophr Res ; 199: 390-394, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29526457

RESUMO

OBJECTIVE: This study examined the effect of adjunctive minocycline on psychopathology and possibly relevant biomarkers in patients with schizophrenia. METHOD: In a 16-week randomized, double-blind, placebo-controlled study, subjects received either minocycline (200mg per day) or placebo. Psychopathology was assessed using the Scale for the Assessment of Negative Symptoms (SANS) and the Positive and Negative Syndrome Scale (PANSS) at baseline and week 16. Plasma levels of tumor necrosis factor α (TNFα), interleukin-1 ß (IL-1ß) and nitric oxide metabolites were assessed at both time points. RESULTS: Fifty-five patients completed the study (27 in the minocycline group, 28 in the placebo group). The minocycline group had significant decreases in the SANS total sore, the PANSS total score and the PANSS negative symptoms score at week 16 compared to the placebo group. In addition, the minocycline group had a significant decrease in plasma levels of nitric oxide metabolites, but no significant difference in changes in plasma levels of IL-1ß or TNF-α, compared to the placebo group at week 16. Further, the more decrease in plasma levels of nitric oxide metabolites was associated with less improvement in negative symptoms. CONCLUSION: The beneficial effect of adjunctive minocycline treatment on negative symptoms might be through mechanisms other than the nitric oxide pathway. The implications for future studies were discussed.


Assuntos
Antipsicóticos/uso terapêutico , Minociclina/uso terapêutico , Óxido Nítrico/metabolismo , Esquizofrenia/sangue , Esquizofrenia/tratamento farmacológico , Adulto , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino , Psicologia do Esquizofrênico , Resultado do Tratamento
7.
Sci Rep ; 7(1): 12699, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28983104

RESUMO

Transdifferentiation of hypertrophic chondrocytes into bone-forming osteoblasts has been reported, yet the underlying molecular mechanism remains incompletely understood. SHP2 is an ubiquitously expressed cytoplasmic protein tyrosine phosphatase. SHP2 loss-of-function mutations in chondroid cells are linked to metachondromatosis in humans and mice, suggesting a crucial role for SHP2 in the skeleton. However, the specific role of SHP2 in skeletal cells has not been elucidated. To approach this question, we ablated SHP2 in collagen 2α1(Col2α1)-Cre- and collagen 10α1(Col10α1)-Cre-expressing cells, predominantly proliferating and hypertrophic chondrocytes, using "Cre-loxP"-mediated gene excision. Mice lacking SHP2 in Col2α1-Cre-expressing cells die at mid-gestation. Postnatal SHP2 ablation in the same cell population caused dwarfism, chondrodysplasia and exostoses. In contrast, mice in which SHP2 was ablated in the Col10α1-Cre-expressing cells appeared normal but were osteopenic. Further mechanistic studies revealed that SHP2 exerted its influence partly by regulating the abundance of SOX9 in chondrocytes. Elevated and sustained SOX9 in SHP2-deficient hypertrophic chondrocytes impaired their differentiation to osteoblasts and impaired endochondral ossification. Our study uncovered an important role of SHP2 in bone development and cartilage homeostasis by influencing the osteogenic differentiation of hypertrophic chondrocytes and provided insight into the pathogenesis and potential treatment of skeletal diseases, such as osteopenia and osteoporosis.


Assuntos
Neoplasias Ósseas/genética , Condromatose/genética , Exostose Múltipla Hereditária/genética , Osteogênese/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Fatores de Transcrição SOX9/genética , Animais , Desenvolvimento Ósseo/genética , Neoplasias Ósseas/fisiopatologia , Cartilagem/crescimento & desenvolvimento , Cartilagem/metabolismo , Cartilagem/patologia , Diferenciação Celular/genética , Proliferação de Células/genética , Transdiferenciação Celular/genética , Condrócitos/metabolismo , Condrócitos/patologia , Condrogênese/genética , Condromatose/fisiopatologia , Exostose Múltipla Hereditária/fisiopatologia , Lâmina de Crescimento/crescimento & desenvolvimento , Lâmina de Crescimento/metabolismo , Lâmina de Crescimento/patologia , Humanos , Hipertrofia/genética , Hipertrofia/patologia , Camundongos , Osteoblastos/metabolismo
8.
Sci Rep ; 7: 43690, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28262807

RESUMO

Insomnia and the inability to sleep affect people's health and well-being. However, its systematic estimates of prevalence and distribution in the general population in China are still lacking. A population-based cluster sampling survey was conducted in the rural and urban areas of Hunan, China. Subjects (n = 26,851) were sampled from the general population, with a follow-up using the Pittsburgh Sleep Quality Index (PSQI) for interview to assess quality of sleep and Insomnia (PSQI score >5). While the overall prevalence of insomnia was 26.6%, and little difference was found between males (26.3%) and females (27.0%); the mean PSQI score was 4.26 (±2.67), and significant higher in females (4.32 ± 2.70) than males (4.21 ± 2.64, p = 0.003). Individuals in the rural areas tended to report a higher PSQI score (4.45 ± 2.81) than urban residents did (4.18 ± 2.60) (p < 0.001) and the estimates of prevalence of insomnia was 29.4% in the rural areas, significant higher than 25.5% in the urban areas (p < 0.001). Multiple logistic regression analysis showed that female gender, older age, higher level of education, being unmarried, living in the rural area, cigarette smoking and alcohol drinking were associated with insomnia. Our study may provide important information for general and mental health research.


Assuntos
Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Sono , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Prevalência , Fatores de Risco , População Rural , Fatores Sexuais , Sono/fisiologia , População Urbana , Adulto Jovem
9.
Bone ; 88: 20-30, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27102547

RESUMO

Loss of Sostdc1, a growth factor paralogous to Sost, causes the formation of ectopic incisors, fused molars, abnormal hair follicles, and resistance to kidney disease. Sostdc1 is expressed in the periosteum, a source of osteoblasts, fibroblasts and mesenchymal progenitor cells, which are critically important for fracture repair. Here, we investigated the role of Sostdc1 in bone metabolism and fracture repair. Mice lacking Sostdc1 (Sostdc1(-/-)) had a low bone mass phenotype associated with loss of trabecular bone in both lumbar vertebrae and in the appendicular skeleton. In contrast, Sostdc1(-/-) cortical bone measurements revealed larger bones with higher BMD, suggesting that Sostdc1 exerts differential effects on cortical and trabecular bone. Mid-diaphyseal femoral fractures induced in Sostdc1(-/-) mice showed that the periosteal population normally positive for Sostdc1 rapidly expands during periosteal thickening and these cells migrate into the fracture callus at 3days post fracture. Quantitative analysis of mesenchymal stem cell (MSC) and osteoblast populations determined that MSCs express Sostdc1, and that Sostdc1(-/-) 5day calluses harbor >2-fold more MSCs than fractured wildtype controls. Histologically a fraction of Sostdc1-positive cells also expressed nestin and α-smooth muscle actin, suggesting that Sostdc1 marks a population of osteochondral progenitor cells that actively participate in callus formation and bone repair. Elevated numbers of MSCs in D5 calluses resulted in a larger, more vascularized cartilage callus at day 7, and a more rapid turnover of cartilage with significantly more remodeled bone and a thicker cortical shell at 21days post fracture. These data support accelerated or enhanced bone formation/remodeling of the callus in Sostdc1(-/-) mice, suggesting that Sostdc1 may promote and maintain mesenchymal stem cell quiescence in the periosteum.


Assuntos
Proteínas Morfogenéticas Ósseas/deficiência , Consolidação da Fratura , Células-Tronco Mesenquimais/citologia , Periósteo/citologia , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Fenômenos Biomecânicos , Proteínas Morfogenéticas Ósseas/metabolismo , Calo Ósseo/patologia , Calcificação Fisiológica , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/patologia , Diferenciação Celular , Proliferação de Células , Osso Cortical/diagnóstico por imagem , Osso Cortical/patologia , Fêmur/patologia , Deleção de Genes , Camundongos Endogâmicos C57BL , Nestina/metabolismo , Tamanho do Órgão , Osteoblastos/metabolismo , Osteogênese , Fenótipo , Fator de Transcrição Sp7/metabolismo , Células-Tronco/metabolismo , Via de Sinalização Wnt , Microtomografia por Raio-X
10.
PLoS One ; 11(2): e0150085, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26910759

RESUMO

Non-bone in vivo micro-CT imaging has many potential applications for preclinical evaluation. Specifically, the in vivo quantification of changes in the vascular network and organ morphology in small animals, associated with the emergence and progression of diseases like bone fracture, inflammation and cancer, would be critical to the development and evaluation of new therapies for the same. However, there are few published papers describing the in vivo vascular imaging in small animals, due to technical challenges, such as low image quality and low vessel contrast in surrounding tissues. These studies have primarily focused on lung, cardiovascular and brain imaging. In vivo vascular imaging of mouse hind limbs has not been reported. We have developed an in vivo CT imaging technique to visualize and quantify vasculature and organ structure in disease models, with the goal of improved quality images. With 1-2 minutes scanning by a high speed in vivo micro-CT scanner (Quantum CT), and injection of a highly efficient contrast agent (Exitron nano 12000), vasculature and organ structure were semi-automatically segmented and quantified via image analysis software (Analyze). Vessels of the head and hind limbs, and organs like the heart, liver, kidneys and spleen were visualized and segmented from density maps. In a mouse model of bone metastasis, neoangiogenesis was observed, and associated changes to vessel morphology were computed, along with associated enlargement of the spleen. The in vivo CT image quality, voxel size down to 20 µm, is sufficient to visualize and quantify mouse vascular morphology. With this technique, in vivo vascular monitoring becomes feasible for the preclinical evaluation of small animal disease models.


Assuntos
Angiografia/métodos , Meios de Contraste/farmacologia , Neoplasias Experimentais , Neovascularização Patológica/diagnóstico por imagem , Microtomografia por Raio-X/métodos , Animais , Camundongos , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/diagnóstico por imagem , Especificidade de Órgãos
11.
West J Nurs Res ; 38(2): 155-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25248661

RESUMO

The purpose of this study was to evaluate the impact of progressive muscle relaxation on state anxiety and self-efficacy in hospitalized patients admitted for an extremity fracture receiving elective surgery. Eighty four patients met the inclusion criteria and all were randomly assigned to either the progressive muscle relaxation group or the control group. The control group received standard orthopedic nursing care, and the experimental group received standard care along with daily progressive muscle relaxation throughout their hospitalization. The State Anxiety Inventory and Self-Efficacy Scales were administered before and after the intervention. Both paired-sample t tests and independent t tests showed that progressive muscle relaxation is effective in reducing state anxiety and enhancing the self-efficacy of patients with extremity fracture undergoing an elective surgery.


Assuntos
Ansiedade/prevenção & controle , Fraturas Ósseas/psicologia , Terapia de Relaxamento/métodos , Autoeficácia , Estresse Psicológico/prevenção & controle , Adulto , Idoso , Feminino , Fraturas Ósseas/reabilitação , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Relaxamento Muscular , Qualidade de Vida
12.
Proc Natl Acad Sci U S A ; 109(35): 14092-7, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22886088

RESUMO

The Wnt antagonist Sost has emerged as a key regulator of bone homeostasis through the modulation of Lrp4/5/6 Wnt coreceptors. In humans, lack of Sclerostin causes sclerosteosis and van Buchem (VB) disease, two generalized skeletal hyperostosis disorders that result from hyperactive Wnt signaling. Unlike sclerosteosis, VB patients lack SOST coding mutations but carry a homozygous 52 kb noncoding deletion that is essential for the transcriptional activation of SOST in bone. We recently identified a putative bone enhancer, ECR5, in the VB deletion region, and showed that the transcriptional activity of ECR5 is controlled by Mef2C transcription factor in vitro. Here we report that mice lacking ECR5 or Mef2C through Col1-Cre osteoblast/osteocyte-specific ablation result in high bone mass (HBM) due to elevated bone formation rates. We conclude that the absence of the Sost-specific long-range regulatory element ECR5 causes VB disease in rodents, and that Mef2C is the main transcription factor responsible for ECR5-dependent Sost transcriptional activation in the adult skeleton.


Assuntos
Remodelação Óssea/genética , Elementos Facilitadores Genéticos/genética , Glicoproteínas/genética , Hiperostose/genética , Fatores de Regulação Miogênica/genética , Osteócitos/fisiologia , Sindactilia/genética , Proteínas Adaptadoras de Transdução de Sinal , Fatores Etários , Animais , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/metabolismo , Feminino , Fêmur/citologia , Fêmur/fisiologia , Deleção de Genes , Glicoproteínas/metabolismo , Hiperostose/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Óperon Lac , Fatores de Transcrição MEF2 , Masculino , Mandíbula/anormalidades , Mandíbula/metabolismo , Camundongos , Camundongos Transgênicos , Fatores de Regulação Miogênica/metabolismo , Osteocondrodisplasias , Osteosclerose/genética , Osteosclerose/metabolismo , Transdução de Sinais/genética , Crânio/anormalidades , Crânio/metabolismo , Sindactilia/metabolismo , Ativação Transcricional/genética
13.
Tissue Eng Part A ; 18(21-22): 2332-42, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22731693

RESUMO

Clinical efforts to repair cartilage defects delivering cells or engineered cartilage implants into the lesions have met with limited success. This study used a critical-size chondral defect model in immunocompromised rat xiphoid cartilage to test whether endogenous chondrogenesis could be achieved using human bone matrix scaffolds to deliver human cartilage particles and/or a variant isoform of fibroblast growth factor-2 (FGF2-variant). Seventy-two male athymic RNU rats were enrolled in this study with eight rats per experimental group. Decellularized and demineralized human bone matrix scaffolds loaded with human articular cartilage particles or heat-inactivated cartilage particles were combined with different doses of the FGF2-variant. Scaffolds were implanted into 3-mm-diameter critical-size defects prepared using a biopsy punch through the center of the xiphoid. The samples were evaluated 28 days postsurgery using X-ray, equilibrium partitioning of ionic contrast microcomputed tomography, and safranin O-stained histological sagittal sections. Scaffolds containing cartilage particles plus the FGF2-variant induced dose-dependent increases in the formation of neocartilage (p<0.05), which was distributed homogeneously throughout the defects in comparison to scaffolds containing only the FGF2-variant. These effects were less pronounced when scaffolds with heat-inactivated cartilage particles were used. These results demonstrate that endogenous repair of chondral defects can be achieved in the absence of exogenous cells or bone marrow, suggesting that a similar approach may be successful for treating chondral lesions clinically.


Assuntos
Matriz Óssea/metabolismo , Cartilagem/patologia , Hospedeiro Imunocomprometido , Regeneração/fisiologia , Alicerces Teciduais/química , Processo Xifoide/patologia , Animais , Cartilagem/diagnóstico por imagem , Humanos , Masculino , Ratos , Ratos Nus , Coloração e Rotulagem , Microtomografia por Raio-X , Processo Xifoide/diagnóstico por imagem
14.
Tissue Eng Part A ; 16(7): 2321-30, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20192719

RESUMO

The aim of this study was to establish a critical-sized nonjoint chondral defect animal model and to evaluate its feasibility for testing cartilage regeneration strategies. Dermal biopsy punches 1-4 mm in diameter were used to create cylindrical full-thickness defects in the center of athymic rat xiphoids. The 3 and 4 mm defects remained unhealed 35 days postsurgery, with a large area in the center that had low proteoglycan content based on contrast-enhanced microCT (EPIC-microCT), radiographic, and histological analyses. In a second step, tissue-engineered cartilage was synthesized by culturing primary bovine articular chondrocytes on poly-L-lactic acid (PLA) scaffolds in a perfusion-shear bioreactor for 28 days. These chondrocyte/PLA constructs or primary bovine chondrocytes were implanted into 3-mm-diameter defects. Empty defects and defects implanted with empty PLA scaffolds were used as controls. Xiphoids were harvested 28 days after surgery and examined with faxitron, microCT, and histology using hematoxylin and eosin and safranin-O staining. Both chondrocyte/PLA constructs and chondrocytes alone formed neocartilage. The results indicate that a 3 mm cylindrical defect in a rat xiphoid is an economic, feasible, and reproductive model to evaluate the potential of various constructs for nonjoint cartilage repair.


Assuntos
Cartilagem Articular/fisiologia , Modelos Animais , Regeneração , Cicatrização , Processo Xifoide/patologia , Animais , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Cartilagem Articular/cirurgia , Bovinos , Glicosaminoglicanos/metabolismo , Masculino , Ratos , Microtomografia por Raio-X , Processo Xifoide/diagnóstico por imagem , Processo Xifoide/cirurgia
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