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1.
Bioinformatics ; 36(3): 735-741, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504177

RESUMO

MOTIVATION: Understanding the mechanisms of client protein interaction with Hsp70 chaperones is essential to analyze the complex dynamics in the context of normal or dysregulated metabolism. Because Hsp70 can bind millions of proteins, including key molecules involved in processes of stemness, tumorigenesis and survival, in silico prediction of Hsp70 interactions has great value in validating possible new clients. Currently, two algorithms are available to predict binding to DnaK-the bacterial Hsp70-but both are based on amino acid sequence and energy calculations of qualitative information-binders and non-binders. RESULTS: We introduce a new algorithm to identify Hsp70 binding sequences in proteins-ChaperISM-a position-independent scoring matrix trained on either qualitative or quantitative chemiluminescence data previously published, which were obtained from the interaction between DnaK and different ligands. Both versions of ChaperISM, qualitative or quantitative, resulted in an improved performance in comparison to other state-of-the-art chaperone binding predictors. AVAILABILITY AND IMPLEMENTATION: ChaperISM is implemented in Python version 3. The source code of ChaperISM is freely available for download at https://github.com/BioinfLab/ChaperISM. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Software , Sequência de Aminoácidos , Proteínas de Choque Térmico HSP70 , Ligação Proteica
2.
Biomed Res Int ; 2015: 240698, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25685773

RESUMO

Background. This work compares the osteoblastic behaviour of a bone marrow (BM) aspirate and a prepared BM concentrate of nucleated cells associated with a glass reinforced hydroxyapatite composite (GRHC) in a microporous pellet formulation. Methods. BM aspirate (30 mL) was collected during 3 orthopedic surgical procedures, and a concentration system was used to achieve 3 rapid preparations of a concentrate of nucleated cells (3 mL) from the BM aspirates. The BM aspirates (53% cell viability; 2.7 × 10(6) nucleated cell/mL) and the BM concentrates (76% cell viability; 2 × 10(7) nucleated cell/mL) were cultured over glass reinforced hydroxyapatite pellets, at the same volume/mass ratio, for 30 days. Cultures performed in standard tissue culture plates were used as control. Results. The colonized BM concentrate/material constructs exhibited a representative osteoblastic proliferation/differentiation pathway, evidenced by a high alkaline phosphatase (ALP) activity, expression of collagen type 1, ALP, BMP-2, M-CSF, RANKL, and OPG, and formation of a calcium phosphate mineralized matrix. A clear improved behaviour was noticed compared to the BM aspirate/material constructs. Conclusions. The results suggest the benefit of using an autologous BM concentrate/material construct in the clinical setting, in bone regeneration applications.


Assuntos
Antígenos de Diferenciação/biossíntese , Células da Medula Óssea/metabolismo , Regeneração Óssea , Regulação da Expressão Gênica , Células-Tronco/metabolismo , Alicerces Teciduais/química , Idoso , Células da Medula Óssea/citologia , Durapatita/química , Feminino , Vidro/química , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco/citologia
3.
Acta Biomater ; 4(2): 370-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17716960

RESUMO

The aim of this study was to evaluate the biological behaviour of porous scaffold structures of Bonelike which is suitable for either direct clinical use or tissue engineering applications. Porous cylindrical specimens 8x10mm were implanted in the lateral aspect of the tibia of 13 patients (mean age 54 years), during osteotomy surgery for the treatment of medial compartment osteoarthritis of the knee. Implanted cylinders were retrieved at the same time as the removal of the blade plates at 3, 6, 9 and 12 months. Scanning electron microscopy and histological evaluations were performed to observe the biological responses of human bone tissue to porous Bonelike. The penetration depth was determined for all implantation periods, and after 6 months it was already possible to see new bone in the centre of the implanted cylinders, which gives 100% of penetration depth for all implantations periods except for 3 months when bone could only be seen in the peripherical region. Regarding the percentage of the area covered by new bone calculated from two-dimensional histological sections, values of 53+/-15, 76+/-12 and 88+/-9% were achieved for 6, 9 and 12 months, respectively. Due to its structural features porous Bonelike permitted effective vascularization and bone ingrowth, and therefore was fully osteointegrated as shown in the histological surveys. A slow biomaterial degradation with implantation time is envisaged since the material has displayed surface degradation. Bonelike scaffolds show potential for complete ingrowth of osseous tissue and restoration of vascularization throughout the defected site.


Assuntos
Substitutos Ósseos , Osseointegração , Idoso , Feminino , Humanos , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Osteoartrite/patologia , Osteoartrite/cirurgia , Osteotomia , Próteses e Implantes , Tíbia/patologia , Tíbia/cirurgia , Fatores de Tempo , Engenharia Tecidual
4.
J Mater Sci Mater Med ; 18(12): 2377-82, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17569003

RESUMO

Two synthetic calcium phosphates in porous wedge shape, Bonelike and a commercial HA/beta-TCP biphasic material, were used as an alternative to bone autografts and allografts in the treatment of medial compartment osteoarthritis of varus knees. The structure of Bonelike has a 3D architecture that is computer controlled, and a composition that mimics the mineral composition of natural bone. The HA/beta-TCP biphasic material used as a control material in this study was prepared using conventional foaming based methods. No signs of inflammatory reactions were observed post-operatively for both materials. After 4 months signs of fusion at the osteotomy site and good integration of the implanted wedges were observed, showing good mechanical resistance. Concerning the final correction attained, the left knee revealed a satisfactory valgus of 10 degrees , but the right one only had a final value of 6 degrees . The clinical evaluation using International Knee Score (IKS) showed good outcome in all parameters with complete range of motion in both knees and climbing stairs without crutches with only slight pain.


Assuntos
Substitutos Ósseos/química , Imageamento Tridimensional/métodos , Osteoartrite do Joelho/cirurgia , Osteotomia/métodos , Próteses e Implantes , Tíbia/cirurgia , Fosfatos de Cálcio/química , Simulação por Computador , Humanos , Hidroxiapatitas/química , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Porosidade , Radiografia , Tíbia/diagnóstico por imagem
5.
J Orthop Res ; 24(5): 953-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16609968

RESUMO

Synthetic bone grafts provide an alternative to autografts and allografts. Bonelike is a patented synthetic bone graft that mimics the mineral composition of bone. The aim of the present work was to assess the biological behavior of Bonelike graft in humans, before using the material in orthopedic applications of bone regeneration, for example, in opening wedge high tibial osteotomies for medial knee osteoarthritis. Bonelike granules were implanted in cortical bone of 11 patients undergoing osteotomies, and new bone formation, osteoconductive properties, and resorption characteristics of the granules were analyzed. The granules ranged from 500 to 1000 microm and were implanted in the lateral aspect of the tibia. The patients' mean age was 59 years (range 48 to 70 years); there were eight women and three men, all suffering from medial compartment osteoarthritis of the knee. At surgery, a 1 x 1 x 1-cm cortical defect was created 3 cm distal to the entry point of the screws, in line with the long axis of tibia. The implanted Bonelike graft sample was extracted for analysis during removal of the metallic prosthesis after implantation times of 6, 9, and 12 months. Radiological follow-up, scanning electron microscopy, histological analysis, and histomorphometric measurements were conducted on the retrieved samples to assess bone regeneration in the defect area. Osteoconductive capacity was demonstrated by extensive mature bone formation around the implanted granules and high levels of percentage bone-to-graft contact (from 67-84%). Bonelike acted as an excellent bioactive scaffold, allowing the migration, proliferation, and differentiation of bone cells on its surface, and therefore regeneration of the defects was achieved in a rapid, controlled manner. Our results suggest that Bonelike graft is an excellent candidate for orthopedic applications where rapid new bone formation is a fundamental requirement.


Assuntos
Substitutos Ósseos , Transplante Ósseo , Osso e Ossos/patologia , Osso e Ossos/ultraestrutura , Próteses e Implantes , Idoso , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Osteogênese
6.
Artigo em Francês | MEDLINE | ID: mdl-14968006

RESUMO

Para-articular osteochondroma, a benign osteoarticular tumor which develops near joints, is, unlike classical osteochondroma, extremely rare. We present the case of a 59-year-old woman who developed a calcified mass in the infrapatellar region. The differential diagnosis between chondrosarcoma, synovial chondromatosis, and para-aticular osteochondroma was only possible after resection and pathology examination of the surgical specimen.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/patologia , Articulação do Joelho/patologia , Osteocondroma/diagnóstico , Osteocondroma/patologia , Osteossarcoma/diagnóstico , Osteossarcoma/patologia , Neoplasias Ósseas/cirurgia , Condromatose Sinovial/diagnóstico , Condromatose Sinovial/patologia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Osteocondroma/cirurgia
7.
Int Orthop ; 22(6): 394-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10093809

RESUMO

The authors present two cases of fractures of posteromedial process of talus. One was treated conservatively and the other by excision. The appearances of the CT scans, the therapeutic options and the mechanisms of injury are discussed.


Assuntos
Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/terapia , Tálus/lesões , Acidentes por Quedas , Adulto , Moldes Cirúrgicos , Fraturas Ósseas/etiologia , Humanos , Masculino , Osteotomia , Modalidades de Fisioterapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Hansenol Int ; 6(2): 130-5, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7349300

RESUMO

Some classifications of Leprosy currently in use are reviewed and the difficulties of their application in field work are analysed. While it is recognized the scientific value of these classifications in order to identify precisely the clinical, bacteriological, histological and immunological aspects of the disease, an alternative simplified classification is suggested, to be used in control programmes. In this classification clinical forms that require the same public health action are put together. Thus, clinical forms are reduced to three basic groups. The clinical and laboratory criteria which define each group are presented, as well as the correlation between this simplified classification and the classic one.


Assuntos
Hanseníase/classificação , Humanos , Hanseníase/prevenção & controle
9.
Hansen. int ; 6(2): 130-5, 1981.
Artigo em Inglês | LILACS | ID: lil-11631

RESUMO

Neste trabalho, os autores apresentam uma revisao nos tipos de classificacao de hanseniase, atualmente em uso, alem de uma analise das dificuldades que surgem na sua aplicacao no trabalho de campo. Embora os autores reconhecam o valor cientifico dessas classificacoes, utilizadas para identificar, de modo preciso, os aspectos clinicos, bacteriologicos, histologicos e imunologicos da hanseniase, ao mesmo tempo sugerem uma classificacao mais simplificaca, como alternativa, para ser aplicada em programas de controle. Nesse novo sistema, as formas clinicas, que exigem o mesmo tipo de acao sanitaria publica foram classificadas juntas, sendo reduzidas, portanto, a tres grupos basicos. Os autores apresentam ainda os criterios clinicos e de laboratorio assim como a correlacao entre os sistemas de classificacao simplificado e classico


Assuntos
Hanseníase , Classificação
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