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1.
Clin Biochem ; 116: 100-104, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37084998

RESUMO

OBJECTIVES: Bone turnover markers (BTM) are measures for understanding the effect of anti-resorptives upon osteoclast activity. Post-hoc trial data suggests reduction in BTM of 40% may represent a target for defining appropriate response to therapy. We modeled clinical application of this target threshold in an individual patient setting where assay measurement uncertainty and biological variation are included. DESIGN: Using serum C-telo-peptide (ß-CTX), we constructed hypothetical scenarios of ß-CTX measurement pre and post bisphosphonate therapy. Using typical ß-CTX assay characteristics (analytical coefficient of variation, CV 5.0%) and published intra-individual ß-CTX data for post-menopausal women (CV 18.0%), we calculated the post-therapy ß-CTX that must be seen on single repeat measure for 95% confidence that the observed result was ≥40% below baseline. Sensitivity analyses considered greater and lesser variations in the combined sources of variation. RESULTS: The one-tailed 95% reference change value for any detectable therapeutic decrease in ß-CTX was 22%. However, to have 95% confidence of having achieved a reduction ≥40%, an observed ß-CTX decrease of ≥56% is required. Larger decreases are needed for scenarios of greater analytical or intra-individual variation. CONCLUSIONS: Although population data suggest a ß-CTX decrease of 40% is commensurate with adequate therapeutic response to anti-resorptives, application to an individual patient where measurement and natural variation are present is problematic. ß-CTX decreases much >40% are required to be confident of having achieved the optimal treatment response. It is uncertain whether this is a legitimate change to be expected in all individual patients and therefore clinical application of this threshold is uncertain.


Assuntos
Densidade Óssea , Peptídeos , Humanos , Feminino , Densidade Óssea/fisiologia , Incerteza , Peptídeos/uso terapêutico , Difosfonatos/farmacologia , Difosfonatos/uso terapêutico , Remodelação Óssea , Biomarcadores , Colágeno Tipo I/farmacologia
2.
Colloids Surf B Biointerfaces ; 223: 113152, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36739675

RESUMO

Fabricating bioartificial bone graft ceramics retaining structural, mechanical, and bone induction properties akin to those of native stem-cell niches is a major challenge in the field of bone tissue engineering and regenerative medicine. Moreover, the developed materials are susceptible to microbial invasion leading to biomaterial-centered infections which might limit their clinical translation. Here, we successfully developed biomimetic porous scaffolds of polyurethane-reinforcedL-cysteine-anchored polyaniline capped strontium oxide nanoparticles to improve the scaffold's biocompatibility, osteo-regeneration, mechanical, and antibacterial properties. The engineered nanocomposite substrate PU/L-Cyst-SrO2 @PANI (0.4 wt%) significantly promotes bone repair and regeneration by modulating osteolysis and osteogenesis. ALP activity, collagen-I, ARS staining, as well as biomineralization of MC3T3-E1 cells, were used to assess the biocompatibility and cytocompatibility of the developed scaffolds in vitro, confirming that the scaffold provided a favorable microenvironment with a prominent effect on cell growth, proliferation, and differentiation. Furthermore, osteogenic protein markers were studied using qRT-PCR with expression levels of runt-related transcription factor 2 (RUNX2), secreted phosphoprotein 1 (Spp-I), and collagen type I (Col-I). The overall results suggest that PU/L-Cyst-SrO2 @PANI (0.4 wt%) scaffolds showed superior interfacial biocompatibility, antibacterial properties, load-bearing ability, and osteoinductivity as compared to pristine PU. Thus, prepared bioactive nanocomposite scaffolds perform as a promising biomaterial substrate for bone tissue regeneration.


Assuntos
Nanofibras , Osteogênese , Cisteína/farmacologia , Alicerces Teciduais/química , Poliuretanos/farmacologia , Nanofibras/química , Materiais Biocompatíveis/química , Engenharia Tecidual/métodos , Regeneração Óssea , Diferenciação Celular , Colágeno Tipo I/farmacologia , Antibacterianos/farmacologia
3.
Food Res Int ; 162(Pt A): 111967, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461217

RESUMO

Obtaining collagen from rabbit meat, skin and ears is a great way to add value to these by-products. The collagen extracts from meat, skin, and ear showed high levels of protein 80.7, 95.5, and 94.5% and yields of 9.0, 24.4, and 23.8% on a dry basis, respectively. SDS-PAGE analysis showed that the collagens mainly consist of type I collagen, and the FTIR spectra displayed the characteristic peaks of amide A, B, I, II, and III; in addition, the collagens showed greater solubility in acidic pH. The foam production capacity of the collagens was low compared with other collagen sources. However, foam rabbit-collagen stability was high. The emulsifying activity index for the meat, skin, and ears was 44.7, 46.6, and 48.2 m2/g, respectively. Based on the results, the meat, skin, and ears of the rabbit proved to be a viable source for collagen extraction and a possible alternative to add value to the by-products (skin and ears) of these raw materials.


Assuntos
Colágeno , Carne , Animais , Coelhos , Pele , Colágeno Tipo I , Eletroforese em Gel de Poliacrilamida
4.
J Struct Biol ; 214(4): 107899, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36208858

RESUMO

To investigate age and site-related changes to human dentin collagen, sound human teeth collected from donors aged 13-29 (young) and 50-74 (aged) years (n = 9/group) were cut to shallow and deep sites. Dentin collagen orientation and fibril bundling was investigated using the Picrosirius Red (PSR) stain observed under cross-polarized light microscopy (Pol), and collagen distribution was investigated using Confocal Laser Scanning Microscopy (CLSM). Collagen types III to I distribution in peritubular dentin (PTD) was revealed using Herovici stain and brightfield microscopy. Image analysis software and linear mixed modelling quantified outcomes. In situ dentin collagen was observed using Xenon Plasma Focussed Ion Beam Scanning Electron Microscopy (Xe PFIB-SEM). The PSR-Pol analysis revealed less coherently aligned and more bundled collagen fibrils in aged dentin (P = 0.005). Deep inner dentin collagen in both groups were less coherently aligned with reduced bundling. Regardless of age, CLSM showed collagen distribution remained stable; and more collagen type III was detectable in PTD located in inner dentin (Young: P = 0.006; Aged: P = 0.008). Observations following Xe PFIB-SEM cross-sectioning showed apatite-like deposits surrounding large intratubular collagen fibers, and evidence of smaller intertubular dentin collagen fibrils in situ. In conclusion, aging changes collagen network architecture, but not distribution or content.


Assuntos
Colágeno Tipo I , Microscopia , Humanos , Dentina
5.
BMC Musculoskelet Disord ; 23(1): 682, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842641

RESUMO

BACKGROUND: Hypoxia in obstructive sleep apnea (OSA) patients during sleep may have an effect on bone metabolism. Few data regarding evaluation of bone metabolism in young individuals diagnosed with OSA. In this study, we aim to identify the association between bone mineral density and OSA in young men (≤ 40 years old of age). METHODS: Consecutive male subjects who underwent polysomnography were enrolled. Serum calcium, 25-hydroxyvitamin-D3, ß-isomerized form C-terminal telopeptide of type I collagen, osteocalcin and procollagen type 1 N-propeptide were measured in all participants, and bone mineral density (BMD) at lumbar spine (L1-L4), femoral neck and hip total were determined by dual energy X-ray absorption (DXA). RESULTS: The population consisted of 85 subjects (mean age 35.53 years). The BMD at lumbar spine (L1-L4) in moderate OSA patients was higher than control and severe OSA group significantly (p = 0.036). After adjustment for confounding factors, stepwise multiple linear regression analyses showed LaSO2 (ß = 0.340, p = 0.008) as an independent explanatory variable for Lumbar L1-L4 BMD, LaSO2 (ß = 0.304, p = 0.037), BMI (ß = 0.393, p = 0.008) for femur neck BMD and BMI (ß = 0.720, p = 0.002) for hip total BMD. CONCLUSIONS: Our finding indicated that there was a relationship between OSA and bone metabolism in younger men, and moderate OSA-related hypoxia positively related with BMD. This study also showed that different degrees of recurrent hypoxia had different effects on bone metabolism, a finding that required further investigation.


Assuntos
Densidade Óssea , Apneia Obstrutiva do Sono , Absorciometria de Fóton , Adulto , Colágeno Tipo I , Estudos Transversais , Colo do Fêmur/diagnóstico por imagem , Humanos , Hipóxia , Vértebras Lombares , Masculino , Apneia Obstrutiva do Sono/diagnóstico
6.
J Biophotonics ; 15(9): e202200036, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35652856

RESUMO

In this article, we offer a novel classification of progressive changes in the connective tissue of dermis in vulvar lichen sclerosus (VLS) relying on quantitative assessment of the second harmonic generation (SHG) signal received from formalin fixed and deparaffinized tissue sections. We formulate criteria for distinguishing four degrees of VLS development: Initial-Mild-Moderate-Severe. Five quantitative characteristics (length and thickness type I Collagen fibers, Mean SHG signal intensity, Skewness and Coherence SHG signal) are used to describe the sequential degradation of connective tissue (changes in the structure, orientation, shape and density of collagen fibers) up to the formation of specific homogeneous masses. Each of the degrees has a characteristic set of quantitatively expressed features. We focus on the identification and description of early, initial changes of the dermis as the least specific. The results obtained by us and the proposed classification of the degrees of the disease can be used to objectify the dynamics of tissue changes during treatment.


Assuntos
Líquen Escleroso Vulvar , Colágeno Tipo I , Tecido Conjuntivo , Feminino , Humanos , Microscopia , Projetos Piloto , Líquen Escleroso Vulvar/diagnóstico por imagem
7.
Eur J Heart Fail ; 24(2): 321-331, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34841615

RESUMO

AIMS: The HOMAGE randomized trial found that spironolactone reduced left atrial volume index (LAVI), E:A ratio, and a marker of collagen type I synthesis (procollagen type I C-terminal propeptide) in patients at risk of heart failure (HF). Previous trials showed that patients with HF, preserved ejection fraction and low serum collagen type I C-terminal telopeptide to matrix metalloproteinase-1 ratio (CITP:MMP-1), associated with high collagen cross-linking, had less improvement in diastolic function with spironolactone. We evaluated the interaction between serum CITP:MMP-1 and spironolactone on cardiac function in the HOMAGE trial. METHODS AND RESULTS: Patients at risk of HF were randomized to spironolactone (n = 260) or not (n = 255). Blood sampling and echocardiography were done at baseline, one and nine months. CITP:MMP-1 was used as an indirect measure of collagen cross-linking. Higher baseline CITP:MMP-1 (i.e. lower collagen cross-linking) was associated with greater reductions in LAVI with spironolactone at both one (p = 0.003) and nine (p = 0.01) months, but no interaction was observed for E:A ratio. Spironolactone reduced LAVI after one and nine months only for those patients in the third tertile of CITP:MMP-1 (estimated lowest collagen cross-linking) [mean differencesspiro/control : -1.77 (95% confidence interval, CI -2.94 to -0.59) and -2.52 (95% CI -4.46 to -0.58) mL/m2 ; interaction pacross-tertiles  = 0.005; interaction pthird tertile  = 0.008] with a similar trend for N-terminal pro-B-type natriuretic peptide which was consistently reduced by spironolactone only in the lowest collagen cross-linking tertile [mean differencesspiro/control : -0.47 (95% CI -0.66 to -0.28) and -0.31 (95% CI -0.59 to -0.04) ng/L; interaction pacross-tertiles  = 0.09; interaction pthird tertile < 0.001]. CONCLUSIONS: These findings suggest that, for patients at risk of HF, the effects of spironolactone on left atrial remodelling may be more prominent in patients with less collagen cross-linking (indirectly assessed by serum CITP:MMP-1).


Assuntos
Remodelamento Atrial , Insuficiência Cardíaca , Biomarcadores , Colágeno Tipo I , Humanos , Fragmentos de Peptídeos , Espironolactona/uso terapêutico , Volume Sistólico
8.
Exp Clin Endocrinol Diabetes ; 130(7): 426-433, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34911084

RESUMO

PURPOSE: To develop a simple and clinically useful assessment tool for osteoporosis in older women with type 2 diabetes mellitus (T2DM). METHODS: A total of 601 women over 60 years of age with T2DM were enrolled in this study. The levels of serum sex hormones and bone metabolism markers were compared between the osteoporosis and non-osteoporosis groups. The least absolute shrinkage and selection operator regularization (LASSO) model was applied to generate a risk assessment tool. The risk score formula was evaluated using receiver operating characteristic analysis and the relationship between the risk score and the bone mineral density (BMD) and T-value were investigated. RESULTS: Serum sex hormone-binding globulin (SHBG), cross-linked C-telopeptide of type 1 collagen (CTX), and osteocalcin (OC) were significantly higher in the osteoporosis group. After adjustment for age and body mass index (BMI), SHBG was found to be correlated with the T-value or BMD. Then, a risk score was specifically generated with age, BMI, SHBG, and CTX using the LASSO model. The risk score was significantly negatively correlated with the T-value and BMD of the lumbar spine, femoral neck, and total hip (all P<0.05). CONCLUSION: A risk score using age, BMI, SHBG, and CTX performs well for identifying osteoporosis in older women with T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Osteoporose , Absorciometria de Fóton , Idoso , Biomarcadores , Densidade Óssea , Colágeno Tipo I , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Pessoa de Meia-Idade , Osteocalcina , Medição de Risco
9.
Medicina (Kaunas) ; 59(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36676667

RESUMO

Background and Objectives: Centipeda minima (L.) is a well-known and traditional pharmaceutical that has been utilized to treat different conditions controlling rhinitis, soothe pain, and decrease swelling. We assessed the impacts of Centipeda minima (L.) extricates (CMTs) on the osteogenic differentiation of cell spheroids made of human-bone-marrow-derived mesenchymal stem cells. Materials and Methods: Mesenchymal stem cells (MSCs) in spheroid 3D culture were generated and propagated in the presence of CMTs ranging from 0 to 1 µg/mL. Cell morphology was measured on Days 1, 3, 5, and 7. The quantitative cellular viability was evaluated on Days 1, 3, 5, and 7. Alkaline phosphatase activity assays were designed to measure the osteogenic differentiation of mesenchymal stem cell spheroids on Day 7. Alizarin Red S staining was performed to investigate the mineralization of cell spheroids on Days 7 and 14. Real-time polymerase chain reactions were used to measure the expression levels of RUNX2 and COL1A1 on Day 14. Western blot techniques were performed to identify the protein expression of Runt-related transcription factor 2 and type I collagen. Results: The control group's mesenchymal stem cells displayed a spheroid shape. There was no noticeable change in morphology with the addition of CMTs at final concentrations of 0.001, 0.01, 0.1, and 1 µg/mL compared with the untreated (control) group. The application of CMTs did not induce a significant change in cell viability. The relative alkaline phosphatase activity values in the 0.001, 0.01, 0.1, and 1 µg/mL CMT groups were 114.4% ± 8.2%, 130.6% ± 25.3%, 87.8% ± 3.4%, and 92.1% ± 6.8%, respectively, considering a control of 100% (100.0% ± 17.9%). On Day 14, calcium deposits were clearly observed in each group. The relative values of Alizarin Red S staining in the 0.001, 0.01, 0.1, and 1 µg/mL CMT groups were 100.1% ± 8.9%, 105.9% ± 0.0%, 109.7% ± 19.1%, and 87.0% ± 40.9%, respectively, considering a control of 100% (100.0% ± 28.7%). The addition of CMT significantly increased RUNX2 expression in the 0.01 µg/mL group and COL1A1 in the 0.001 and 0.01 µg/mL groups. Normalization of protein expression showed that the addition of CMTs significantly increased type I collagen expression in the 0.001, 0.01, and 1 µg/mL groups. Conclusions: In conclusion, CMTs influence the osteogenic differentiation of bone-marrow-derived mesenchymal stem cells and the use of CMTs may positively influence the osteogenic differentiation of cell spheroids.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Colágeno Tipo I/metabolismo , Sobrevivência Celular , Fosfatase Alcalina , Diferenciação Celular , Células Cultivadas
10.
Chem Commun (Camb) ; 57(91): 12183-12186, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34730136

RESUMO

The stiffnesses, ß-structures, hydrogen bonds, and vibrational modes of wild-type collagen triple helices are compared with osteogenesis imperfecta-related mutants using integrative structural and dynamic analysis via molecular dynamics simulations and Markov state models. Differences in these characteristics are strongly related to the unwound structural states in the mutated regions that are specific to each mutation.


Assuntos
Colágeno Tipo I/análise , Glicina/análise , Cadeias de Markov , Simulação de Dinâmica Molecular , Osteogênese Imperfeita/diagnóstico , Colágeno Tipo I/genética , Glicina/genética , Humanos , Conformação Molecular , Mutação , Osteogênese Imperfeita/genética
11.
Chem Biol Interact ; 349: 109674, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34562440

RESUMO

We have assessed the molecular role of Rutin and rutin-Zn(II) complex on osteoblast differentiation and mineralization in human dental pulp cells and zebrafish model. The biocompatibility of the rutin-Zn(II) complex was determined using MTT and chick embryotoxicity assays. Alizarin red staining and ALP measurements were performed to study the osteogenic role of Rutin and rutin-Zn(II) complex at the cellular level in hDPSCs. At molecular level, following rutin and rutin-Zn(II) exposure, the mRNA expression profile of osteoblast markers such Runx2, type 1 col, OC, and ON were investigated. In addition to this, the expression of negative regulators of osteoblast development such Smad7, Smurf1, and HDAC7 waere studied by Real time RT-PCR analysis. The osteogenic role of prepared complex under in vivo was studied by an in-house zebrafish scale model followed by osteoblast differentiation markers expression profiling and Ca:P level measurement by ICP-MS. Rutin and the rutin-Zn(II) complex were found to be non-toxic till 10 µM and increased the expression of osteoblast differentiation marker genes. It also enhanced calcium deposition in both in vitro and in vivo models. Osteogenic property of rutin-Zn(II) in hDPSCs was found be mediated by Smad7, Smurf1, and HDAC7 and enhancing Runx2 expression. Our study warrants the possible use of rutin-Zn(II) as naïve agent or in combination with other bone scaffolding systems/materials for bone tissue engineering applications.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Osteogênese/efeitos dos fármacos , Rutina/química , Zinco/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Polpa Dentária/citologia , Humanos , Osteocalcina/genética , Osteocalcina/metabolismo , Proteína Smad7/genética , Proteína Smad7/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Peixe-Zebra/metabolismo
12.
Sci Rep ; 11(1): 19248, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34584173

RESUMO

The discovery of the expression of opioid receptors in the skin and their role in orchestrating the process of tissue repair gave rise to questions regarding the potential effects of clinical morphine treatment in wound healing. Although short term treatment was reported to improve tissue regeneration, in vivo chronic administration was associated to an impairment of the physiological healing process and systemic fibrosis. Human mesenchymal stem cells (hMSCs) play a fundamental role in tissue regeneration. In this regard, acute morphine exposition was recently reported to impact negatively on the functional characteristics of hMSCs, but little is currently known about its long-term effects. To determine how a prolonged treatment could impair their functional characteristics, we exposed hMSCs to increasing morphine concentrations respectively for nine and eighteen days, evaluating in particular the fibrogenic potential exerted by the long-term exposition. Our results showed a time dependent cell viability decline, and conditions compatible with a cellular senescent state. Ultrastructural and protein expression analysis were indicative of increased autophagy, suggesting a relation to a detoxification activity. In addition, the enhanced transcription observed for the genes involved in the synthesis and regulation of type I collagen suggested the possibility that a prolonged morphine treatment might exert its fibrotic potential risk, even involving the hMSCs.


Assuntos
Células-Tronco Mesenquimais/efeitos dos fármacos , Morfina/toxicidade , Cicatrização/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/análise , Colágeno Tipo I/metabolismo , Fibrose , Humanos , Células-Tronco Mesenquimais/fisiologia , Cultura Primária de Células , Testes de Toxicidade Subaguda
13.
J Histochem Cytochem ; 69(10): 633-643, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34549650

RESUMO

Collagen has a major role in the structural organization of tendons. Picrosirius red (PSR) staining viewed under polarized light microscopy is the standard method to evaluate the organization of collagen fibers in tissues. It is also used to distinguish between type I and type III collagen in tissue sections. However, accurate analysis and interpretation of PSR images are challenging because of technical factors and historical misconceptions. The aim of this study was to clarify whether collagen types I and III can be distinguished by PSR staining in rat Achilles tendons, using double immunohistochemistry as the positive control. Our findings showed that PSR staining viewed with polarized light microscopy was suitable for qualitative and quantitative assessment of total collagen but was not able to distinguish collagen types. We found it critical to use a polarizing microscope equipped with a rotating stage; tendon section orientation at 45° with respect to crossed polarizers was optimal for the qualitative and quantitative assessment of collagen organization. Immunohistochemistry was superior to PSR staining for detection of collagen type III. We also compared formalin and Bouin solution as fixatives. Both produced similar birefringence, but formalin-fixed tendons provided higher quality histological detail with both hematoxylin-eosin and immunostaining.


Assuntos
Compostos Azo/química , Colágeno Tipo III/análise , Colágeno Tipo I/análise , Coloração e Rotulagem , Tendões/química , Animais , Ratos , Ratos Sprague-Dawley
14.
Biomater Sci ; 9(17): 5917-5927, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34291253

RESUMO

Fibroblasts are a diverse population of connective tissue cells that are a key component in physiological wound healing. Myofibroblasts are differentiated fibroblasts occurring in various physiological and pathological conditions, like in the healing of wounds or in the tumour microenvironment. They exhibit important functions compared to fibroblasts in terms of proliferation, protein secretion, and contractility. The gold standard to distinguish myofibroblasts is alpha-smooth muscle actin (αSMA) expression and its incorporation in stress fibres, which is only revealed by gene expression analysis and immunostaining. Here, we introduce an approach to functionally determine the myofibroblast status of live fibroblasts directly in in vitro cell culture by analysing their ability to contract the extracellular matrix around them without the need for labelling. It is based on particle image velocimetry algorithms applied to dynamic deformations of the extracellular matrix network structure imaged by phase contrast microscopy. Advanced image analysis allows us to distinguish between various differentiation stages of fibroblasts including the dynamic change over several days. We further apply machine learning classification to automatically evaluate different cell culture conditions. With this new method, we provide a versatile tool to functionally evaluate the dynamic process of fibroblast differentiation. It can be applied for in vitro screening studies in biomimetic 3D cell cultures with options to extend it to other cell systems with contractile phenotypes.


Assuntos
Fibroblastos , Miofibroblastos , Actinas , Diferenciação Celular , Células Cultivadas , Colágeno Tipo I , Reologia
15.
Acta Histochem ; 123(6): 151762, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34332229

RESUMO

Nile tilapia (Oreochromis niloticus) skin is a well-known biomaterial used as an occlusive dressing for burn treatment. It is also an inexpensive and important source of collagen. This study aims to describe the ultrastructural aspects of Nile tilapia skin, assess its collagen amount and organization, and compare quantitative methods of histochemical and immunohistochemical analysis (in all sterilization steps for use in burn dressings). One sample (0.5 × 0.5 cm) of ten different fish skins was divided in four groups: in natura skin (IN), chemical sterilization (CH), additional irradiation (30 kGy) (IR), and skins used in burn treatment (BT) to compare histochemical and immunohistochemical findings of collagen amount and describe ultrastructural aspects through scanning electron microscopy. The amount of type I collagen decreased during sterilization and clinical use owing to gradual reduction of immunostaining (anti-collagen-I) and decreasing fiber thickness of the collagen, when compared to type III (Picrosirius-red-polarized light). The collagen fibers were rearranged at each sterilization step, with a low collagen percentage and large structural disorganization in BT. The amount of type-I collagen was further reduced after BT (p < 0.05). Both the methods did not exhibit a quantified value difference (p = 0.247), and a positive correlation (r = 0.927; 95 % CI = 0.720-0.983) was observed between them, with concordance for collagen quantification in similar samples, presenting a low systematic error rate (Dalberg coefficient: 6.70). A significant amount of type-I collagen is still observed despite sterilization, although clinical application further reduces type I collagen. Its quantification can be performed both by immunohistochemistry and/or Picrosirius Red reliably.


Assuntos
Ciclídeos , Colágeno Tipo I/química , Proteínas de Peixes/química , Microscopia Eletrônica de Varredura , Pele , Animais , Queimaduras/terapia , Pele/química , Pele/ultraestrutura
16.
Ann Agric Environ Med ; 28(2): 326-330, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34184518

RESUMO

INTRODUCTION: Estrogen deficiency found in postmenopausal women may lead to disturbances in the balance of bone metabolism. Study of the influence of estradiol on markers of bone turnover may help to understand the mechanisms of bone metabolism and to monitor osteoporosis therapy in postmenopausal women at high risk of fractures. The aim of the study was evaluation of the effect of estradiol on the basic markers of bone turnover in postmenopausal women. MATERIAL AND METHODS: The study was conducted in a group of 92 postmenopausal women, divided into two groups: Gr-1 with low estradiol levels ≤ 10 pg/ml and Gr-2 with reference estradiol levels ≥ 25 pg/ml). Basic markers of bone turnover were examined: Ctx (C-terminal cross-linked telopeptide of type I collagen alpha chain) and OC (osteocalcin); pro-resorptive cytokines: IL-6 and TNF-α; vitamin 25(OH)D3 and lipid profile. Women was also analyzed according to demographic and clinical data. RESULTS: A positive relationship was found between estradiol and the main bone formation marker - OC (p = 0.041, r = 0.213) and IL-6, TNF-α (p = 0.007, r = 0.281 and p = 0.018, r = 0.246, respectivly, but only in the group with a reference hormone level. Moreover, the main markers of bone turnover: Ctx and OC showed a mutual positive correlation (p = 0.013; r = 0.257) in women with reference estradiol levels. Relationships between markers of bone remodeling, pro-resorptive cytokines and vitamin D3 depending on the level of estradiol showed no statistically significant correlation. CONCLUSIONS: The study showed that only in women with the reference estradiol level (≥ 25 pg/ml) were the bone formation and resorption processes balanced.


Assuntos
Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Biomarcadores/metabolismo , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Feminino , Humanos , Interleucina-6/metabolismo , Pessoa de Meia-Idade , Osteocalcina/metabolismo , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/fisiopatologia , Pós-Menopausa/efeitos dos fármacos , Pós-Menopausa/metabolismo , Vitamina D/metabolismo
17.
Eur J Heart Fail ; 23(6): 933-944, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33928704

RESUMO

AIMS: To determine the prognostic value of multilevel assessment of fibrosis in dilated cardiomyopathy (DCM) patients. METHODS AND RESULTS: We quantified fibrosis in 209 DCM patients at three levels: (i) non-invasive late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR); (ii) blood biomarkers [amino-terminal propeptide of procollagen type III (PIIINP) and carboxy-terminal propeptide of procollagen type I (PICP)], (iii) invasive endomyocardial biopsy (EMB) (collagen volume fraction, CVF). Both LGE and elevated blood PICP levels, but neither PIIINP nor CVF predicted a worse outcome defined as death, heart transplantation, heart failure hospitalization, or life-threatening arrhythmias, after adjusting for known clinical predictors [adjusted hazard ratios: LGE 3.54, 95% confidence interval (CI) 1.90-6.60; P < 0.001 and PICP 1.02, 95% CI 1.01-1.03; P = 0.001]. The combination of LGE and PICP provided the highest prognostic benefit in prediction (likelihood ratio test P = 0.007) and reclassification (net reclassification index: 0.28, P = 0.02; and integrated discrimination improvement index: 0.139, P = 0.01) when added to the clinical prediction model. Moreover, patients with a combination of LGE and elevated PICP (LGE+/PICP+) had the worst prognosis (log-rank P < 0.001). RNA-sequencing and gene enrichment analysis of EMB showed an increased expression of pro-fibrotic and pro-inflammatory pathways in patients with high levels of fibrosis (LGE+/PICP+) compared to patients with low levels of fibrosis (LGE-/PICP-). This would suggest the validity of myocardial fibrosis detection by LGE and PICP, as the subsequent generated fibrotic risk profiles are associated with distinct cardiac transcriptomic profiles. CONCLUSION: The combination of myocardial fibrosis at CMR and circulating PICP levels provides additive prognostic value accompanied by a pro-fibrotic and pro-inflammatory transcriptomic profile in DCM patients with LGE and elevated PICP.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/patologia , Colágeno Tipo I , Meios de Contraste , Fibrose , Gadolínio , Insuficiência Cardíaca/patologia , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Modelos Estatísticos , Miocárdio/patologia , Valor Preditivo dos Testes , Prognóstico
18.
Knee ; 29: 418-425, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33721626

RESUMO

BACKGROUND: Cell based therapy in cartilage repair predominantly involves the use of chondrocytes and mesenchymal stromal cells (MSC). Co-culture systems, due to their probable synergistic effect on enhancement of functional chondrogenesis and reduction in terminal differentiation have also been attempted. Chondroprogenitors, derived from articular cartilage and regarded as MSCs, have recently garnered interest for consideration in cartilage regeneration to overcome limitations associated with use of conventional cell types. The aim of this study was to assess whetherco-culturing bone marrow (BM)-MSCs and chondroprogenitors at different ratios would yield superior results in terms of surface marker expression, gene expression and chondrogenic potential. METHODS: Human BM-MSCs and chondroprogenitors obtained from three osteoarthritic knee joints and subjected to monolayer expansion and pellet cultures (10,000 cells/cm2) as five test groups containing either monocultures or co-cultures (MSC: chondroprogenitors) at three different ratios (75:25, 50:50 and 25:75) were utilized. RESULTS: Data analysis revealed that all groups exhibited a high expression of CD166, CD29 and CD49e. With regard to gene expression, high expression of SOX9, Aggrecan and Collagen type I; a moderate expression of Collagen type X and RUNX2; with a low expression of Collagen type II was seen. Analysis of pellet culture revealed that chondroprogenitor monoculture and chondroprogenitor dominant coculture, exhibited a subjectively larger pellet size with higher deposition of Collagen type II and glycosaminoglycan. CONCLUSION: In conclusion, this study is suggestive of chondroprogenitor monoculture superiority over MSCs, either in isolation or in a coculture system and proposes further analysis of chondroprogenitors for cartilage repair.


Assuntos
Cartilagem Articular/citologia , Técnicas de Cultura de Células/métodos , Células-Tronco Mesenquimais/citologia , Osteoartrite do Joelho/patologia , Agrecanas/genética , Agrecanas/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Biomarcadores/metabolismo , Cartilagem Articular/fisiologia , Diferenciação Celular , Condrogênese/genética , Técnicas de Cocultura , Colágeno Tipo I/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Feminino , Expressão Gênica , Humanos , Articulação do Joelho/citologia , Masculino , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade
19.
Biomark Med ; 14(13): 1265-1275, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33021388

RESUMO

The pro-fibrotic milieu, as the result of the extracellular matrix remodeling, is a central feature in the pathophysiology of heart disease and contributes to its high morbidity and mortality. Fibrosis is a recognized risk factor for development of heart failure and arrythmias and is usually detected by cardiac magnetic resonance or endomyocardial biopsy. Collagen type I and type III are major components of the collagen network, and the assessment of their derived biomarkers could serve as estimate of the myocardial fibrotic content. This review summarizes data from numerous studies in which these biomarkers have proven their diagnostic and prognostic utility, setting the stage for further randomized clinical trials that might translate into early implementation of antifibrotic therapies.


Assuntos
Colágeno Tipo III/metabolismo , Colágeno Tipo I/metabolismo , Cardiopatias/metabolismo , Animais , Biomarcadores/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo III/genética , Fibrose/genética , Fibrose/metabolismo , Cardiopatias/genética , Cardiopatias/patologia , Humanos
20.
Bone ; 140: 115547, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32730936

RESUMO

OBJECTIVE: Osteogenesis imperfecta (OI) is commonly associated with short stature, but it is unclear whether this is exclusively secondary to fractures and bone deformities or whether there is a primary defect in longitudinal bone growth. As metacarpal and phalangeal bones are rarely affected by fractures and deformities, any length deficits in these bones should reflect a direct disease effect on longitudinal growth. This study therefore assessed the relationship of hand bone length with clinical OI type and genotype. STUDY DESIGN: Prospective study. RESULTS: The length of all 19 tubular hand bones were measured in 144 individuals (age 6 to 57 years; 68 female) who had OI caused by COL1A1 or COL1A2 variants. Measurements of bone length were converted to z-scores using published reference data. Bone length was mostly normal in OI type I but was significantly decreased in OI types III and IV. Mean hand bone length z-score (i.e., the average length z-score of all 19 bones of a hand) was -0.2 for OI type I, -2.9 for OI type III and -1.2 for OI type IV. Mean hand bone length z-score was positively associated with height z-score (r2 = 0.65, P < 0.001). Regarding genotype-phenotype correlations, mean hand bone length z-score was close to 0 in individuals with COL1A1 mutations leading to haploinsufficiency but were significantly lower in the presence of mutations leading to triple-helical glycine substitutions in either the alpha 1 or alpha 2 chain of collagen type I. CONCLUSION: COL1A1 and COL1A2 mutations affect bone growth not only by inducing fractures and bone deformities, but also through longitudinal growth deficits in bones that do not fracture or deform.


Assuntos
Desenvolvimento Ósseo , Osteogênese Imperfeita , Adolescente , Adulto , Criança , Colágeno Tipo I/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Osteogênese Imperfeita/diagnóstico por imagem , Osteogênese Imperfeita/genética , Estudos Prospectivos , Adulto Jovem
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