A elasticidade do ligamento colateral medial da articulação do cotovelo de cão não advém de elastina

A literatura relata que ligamentos consistem de tecido conjuntivo denso, composto por água, colágeno tipos I e III, diversas proteoglicanas, pouca elastina e várias outras substâncias. Além disso, os ligamentos, quando testados in vitro com tensão longitudinal e unidirecional, apresentam um comportamento mecânico não-linear, ou seja, as fibras colágenas são alongadas aos poucos, perdendo seu padrão ondulado, até que todas estejam no limite máximo de tração e iniciem o rompimento. Portanto, no presente estudo avaliou-se a presença de fibras elásticas (elastina) no ligamento colateral medial do cotovelo de cães adultos para ponderar se a elasticidade do referido ligamento deve-se à presença de fibras elásticas ou às propriedades elásticas do colágeno ou à combinação de ambas. Foram utilizadas quatro articulações, de machos e fêmeas em igual proporção, das quais foram adquiridas as amostras das porções médias dos ligamentos colaterais mediais para a rotina histológica. Os cortes foram corados pela técnica de Weigert, e não foi observada a presença de fibras elásticas, detectável por esta técnica à microscopia de luz. Concluiu-se que a elasticidade do ligamento colateral medial do cotovelo de cão deve-se, principalmente, ao padrão ondulado das fibras colágenas, devido à quantidade ínfima ou até à inexistência de fibras elásticas nesta estrutura.

Características anatômicas e morfométricas do ligamento oblíquo do cotovelo de eqüinos

Neste trabalho, algumas características anatômicas e morfométricas do ligamento oblíquo do cotovelo do eqüino foram descritas em dez animais adultos, sem raça definida, que não apresentavam afecções dos órgãos locomotores. O ligamento oblíquo origina-se dorsal à fossa radial do úmero, atravessa obliquamente a superfície cranial do cotovelo e se divide em uma porção longa, que se insere na tuberosidade radial, e em outra curta, que se une à porção longa do ligamento colateral medial. Foram efetuadas medidas visando a obter o comprimento e a largura máximas entre a origem e a inserção do ligamento oblíquo, não sendo observadas diferenças (P>0,05) nas comparações feitas entre os sexos e os antímeros. O ligamento oblíquo contribui no efeito mola e na manutenção da estabilidade da articulação do cotovelo do eqüino. Pela particularidade de sua localização, cranial à articulação, o ligamento oblíquo possui ação frenadora, impedindo a extensão completa da referida articulação.

Descrição anátomo-topográfica do coração da paca (Agouti paca)

Background: The domestic animals heart is a conical hollow viscera, surrounded by pericardium, laterally compressed, accompanying the thorax shape. Atriums constituted the heart basis and their auricles partially bound the initial portion of the aorta and pulmonary trunk. In mammals, heart is kept suspended in the thoracic cavity and the pericardic sac is fixed dorsally by great veins and arteries roots, and ventrally fixed to the sternum, although its fixation to the diaphragm varies among species. This paper aimed to describe morphological aspects of the heart of the paca, the second biggest Brazilian rodent.Materials, Methods & Results: There were used 12 hearts of adult pacas for this study, obtained from the UNESP, Jaboticabal, SP, which died due fights or anesthesia during bandages or radiograph exams. The thoracic aorta was filled with colored latex and the animal was set in a 10% formaldehyde solution for at least 72 hours. The thoracic cavity was dissected and hearts individualized and measured with a paquimeter, lateromedially, craniocaudally and dorsoventrally. The paca heart is placed between the first and fifth intercostal space (ICS), in a craniocaudal oblique position; its basis is craniodorsally positioned, on the middle third between the first and second ICS and its apex is located near the sternodiaphragmatic joint, on the fifth ICS, tilted to the left antimere. The heart is surrounded by pericardium, which from ventrocaudally is originated the sternopericardic ligament, that continues as phrenopericardic ligament. At the heart basis, the rising of the pulmonary trunk was observed and the conus arteriosus formed a typical projection. The aorta also rised from the heart basis and its arch, which was caudally curved, crossed dorsally the pulmonary trunk; the right cranial and caudal cava veins drained to the right atrium. There is a left cranial cava vein, which surrounded the left atrium and joined the right caudal cava vein on the right atrium. The azygos vein joins the right cranial cava vein and four pulmonary veins drained to the left atrium. At palpation, a hard structure on the rising of the aorta was observed, similarly to a cartilaginous tissue, which would be part of the cardiac skeleton. The left and right coronary arteries were observed in all hearts.Discussion: The paca heart is anatomica and topographically similar to those of domestic mammals, differing from them for being placed one intercostal space more cranial and due to the presence of two cranial cava veins, the left and the right ones, besides the presence of the caudal cava vein. This vascular description is similar to that of small rodents, as rats and mice. In paca heart, the sinus venous, the terminal crest, the oval fossa, the atrioventricular valvae, the papillary muscles and tendinous cords, besides smooth atriums and auricles covered by pectinate muscles, were observed. The sternopericardic ligament, which is dorsally elongated as phrenopericardic ligament, is similar to the one present in humans, pigs, castors, and different from the one observed in carnivorous, that presents the phrenopericardic ligament and from the one of horses and ruminants, which present the sternopericardic ligament.

Correlação entre torque, equlíbrio e função do joelho após reconstrução do LCA

Background: Several studies emphasize the importance of assessing the knee function after anterior cruciate ligament (ACL) reconstruction. The influence of several variables on the function of these patients has been analyzed, but there is no consensus in the science literature. Purpose: To evaluate the correlation between the torque and balance on the knee function after ACL reconstruction. Methods: 23 males patients with ACL reconstruction were tested. The procedures of the study included analysis of concentric peak torque at 60o/s and 180o/s of quadriceps femoris and hamstring muscle with a isokinetic dynamometer. The balance in single-limb stance was measured with stabilometry. The functional performance were performed by two hop tests. To estimate the subjective function of the patients was applied Lysholm Knee Scoring Scale and a Global Rating scale. Results: The analysis of data showed a moderate positive correlation between knee extensor torque and functional performance tests (r= 0,48; p=0,02). A moderate negative correlation was found between the two variables of the stabilometry center of pressure and average speed of centre of pressure and the Global Rating scale (r = -0.4, p = 0,04 and r = -0,49, p = 0 ,02, respectively). No correlation was found between peak torque and balance in single-limb stance. Conclusion: The results of the present study suggest that knee extensor strength and postural balance have some influence on knee function in patients after ACL reconstruction

Análise citogenética de células-tronco derivadas do subendotélio da veia umbilical humana

Mesenchymal stem cells (MSCs) are known as a population of multi-potential cells able to proliferate and differentiate into multiple mesodermal tissues including bone, cartilage, muscle, ligament, tendon, fat and stroma. Several applications of the study of EC can be emphasized the therapeutic techniques such as guided bone regeneration by implantation of EC in the affected site, without the need for bone grafts, using titanium as a vehicle. The process of cryopreservation is essential for the maintenance of cell cultures, since the cell line is frozen, it can be maintained in liquid nitrogen for an indefinite period and then thawed for therapeutic or experimental purposes. The aim of this study was to isolate a population of MSCs derived from the subendothelium of the umbilical vein human (MSCs-SUVH) to assess cytogenetic analysis by the possibility of appearance of chromosomal changes in two different situations: MSCs-SUVH regarding the process of cryopreservation and MSCs-SUVH grown on the surface of titanium. Flow cytometry analysis revealed that, this cell population was positive for the markers CD29, CD73 and CD90, but there was no expression of hematopoietic lineage markers, such as CD14, CD34 and CD45 and demonstrated capacity for osteogenic differentiation. The chromosomes obtained from the primary culture of MSCs-SUVH were analyzed by GTW banding technique, and results are described as guidelines to ISCN 2005. There was not the emergence of clonal chromosomal changes in the MSCs-SUVH in different situations analyzed. However one of the strings presented a balanced paracentric inversion, probably a cytogenetic constitutional alterations, which was present before and after the experimental situations that the MSCs-SUVH was submitted

Adesão de células mesenquimais da medula óssea de camundongos e do ligamento periodontal de ratos a diferentes superfícies de titânio: estudo comparativo in vitro

The present experiment used cell culture to analyze the adhesion capacity of mouse mesenchymal bone marrow cells and rat periodontal ligament to different titanium surfaces. Grade II ASTM F86 titanium discs 15mm in diameter and 1.5mm thick were used and received 2 distinct surface treatments (polished and cathodic cage plasma nitriding). The cells were isolated from the mouse bone marrow and rat periodontal ligament and cultured in α-MEM basic culture medium containing antibiotics and supplemented with 10% FBS and 5% CO2, for 72 hours at 37ºC in a humidified atmosphere. Subculture cells were cultured in a 24-well plate with a density of 1 x 104 cells per well. The titanium discs were distributed in accordance with the groups, including positive controls without titanium discs. After a 24-hour culture, the cells were counted in a Neubauer chamber. The results show that both the mouse mesenchymal bone marrow cells and rat periodontal ligament cells had better adhesion to the control surface. The number of bone marrow cells adhered to the polished Ti surface was not statistically significant when compared to the same type of cell adhered to the Ti surface treated by cathodic cage plasma nitriding. However a significant difference was found between the control and polished Ti groups. In relation to periodontal ligament cell adhesion, a significant difference was only found between the control and plasma-treated Ti surfaces. When comparing equal surfaces with different cells, no statistically significant difference was observed. We can therefore conclude that titanium is a good material for mesenchymal cell adhesion and that different material surface treatments can influence this process

A influência da criopreservação nas células mesenquimais indiferenciadas do ligamento periodontal de humanos análise comparativa in vitro

Cryopreservation is a process where cells or biological tissues are preserved by freezing at very low temperatures and aims to cease reversibly, in a controlled manner, all the biological functions of living tissues, i.e., maintain cell preservation so that it can recover with high degree of viability and functional integrity. This study aimed to evaluate the influence of cryopreservation on the mesenchymal stem cells originating from the periodontal ligament of human third molars by in vitro experiments. Six healthy teeth were removed and the periodontal cells grown in culture medium containing α-MEM supplemented with antibiotics and 15% FBS in a humidified atmosphere with 5% CO2 at 37° C. Cells isolated from each sample were divided into two groups: Group I - immediate cell culture (not fresh cryopreserved cells) and Group II - cell cryopreservation, during a period of 30 days. Analyses of rates of cell adhesion and proliferation in different groups were performed by counting the cells adhered to the wells, in intervals of 24, 48 and 72 hours after the start of cultivation. The number of cells in each well was obtained by counting viable cells with the use of hemocytometer and the method of exclusion of cells stained by trypan blue. The difference between groups for each of the times was analyzed by Wilcoxon test. Regarding the temporal evolution for each group, analysis was done by Friedman's test to verify the existence of differences between times and, when it existed, the Wilcoxon penalty was applied. The results showed no statistically significant difference between the two groups analyzed in this study. Therefore, we conclude that the cryopreservation process, after a period of 30 days, did not influence the cell type studied, and there was no difference in growth capacity in vitro between the groups

Avaliação in vitro da adesão e proliferação de células mesenquimais do ligamento periodontal humano em diferentes superfícies de titânio

In the last years, many scientific researches in implantology have been focused on alternatives that would provide higher speed and quality in the process of osseointegration. Different treatment methods can be used to modify the topographic and chemical properties of titanium surface in order to optimize the tissue-implant reactions by a positive tissue response. This study aimed to evaluate the adhesion and proliferation of mesenchymal cells from human periodontal ligament on two different titanium surfaces, using cell culture techniques. Grade II titanium discs received different surface treatments, forming two distinct groups: polished and cathodic cage plasma nitriding. Human periodontal ligament mesenchymal cells were cultured on titanium discs in 24-well cell culture plates, at a density of 2 x 104 cells per well, including wells with no discs as positive control. Data obtained by counting the cells that adhered to the titanium surfaces (polished group and cathodic cage group) and to the plastic surface (control group), in the 24, 48 and 72-hour periods after plating, were used to analyze cell adhesion and proliferation and to obtain the cell growing curve in the different groups. The data were submitted to nonparametric analysis and the differences between groups were compared by Kruskal-Wallis and Friedman statistical tests. No statistically significant differences were found in the cells counts between the groups (p>0.05). It was concluded that both treatments produced surfaces compatible with the adhesion and proliferation of human periodontal ligament mesenchymal cells

Influência da laserterapia na proliferação de células-tronco do ligamento periodontal humano

Low level laser irradiation (LLLI) has been used in Dentistry to promote wound healing and tissue regeneration. The literature shows a positive effect of LLLI on cell proliferation, but little is known about their effectiveness in promoting stem cells proliferation. The aim of this study was to evaluate the effect of LLLI on the proliferative rate of human periodontal ligament stem cells. Extracts of periodontal ligament were isolated from two third molars removed by surgical and/or orthodontic indication. After enzymatic digestion, the cells were grown in α-MEM culture medium supplemented with antibiotics and 15% fetal bovine serum. On the third subculture, the cells were irradiated with a InGaAlP-diode laser, using two different energy densities (0,5J/cm 2 - 16 seconds and 1,0J/cm² - 33 seconds), with wavelength of 660nm and output power of 30mW. A new irradiation, using the same parameters, was performed 48h after the first. A control group (non irradiated) was kept under the same experimental culture conditions. The Trypan blue exclusion test and the mitochondrial activity of the cells measured by MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] essay were performed to assess the cell proliferation in the intervals of 0, 24, 48 e 72 h after irradiation. The data of cell counts were submitted to nonparametrical statistical tests (Kruskal-Wallis and Mann-Whitney), considering a confidence interval of 95%. DAPI (4 -6-Diamidino-2-phenylindole) staining of the cells was performed at 72h interval to evaluate possible nuclear morphological changes induced by LLLI. The results of this study show that the energy density of 1,0 J/cm² promoted greater cell proliferation compared to the other groups (control and 0,5 J/cm²) at intervals of 48 and 72h. The mitochondrial activity measured by MTT essay showed similar results to the Trypan blue cell counting test. The group irradiated with 1,0J/cm² exhibited a significantly higher MTT activity in the intervals of 48 and 72h, when compared to the group irradiated with 0,5J/cm². No nuclear morphological change was observed in the cells from the three groups studied. It is concluded that LLLI has stimulatory effects on the proliferation of human periodontal ligament stem cells. Therefore, the use of laser irradiation in this cell type may be important to promote future advances in periodontal regeneration

Análise comparativa das propriedades mecânicas do ligamento da patela e do tendão calcâneo

Com a finalidade de se comparar as propriedades mecânicas do ligamento da patela e do tendão calcâneo foram realizados ensaios de tração em material obtido de 25 cadáveres humanos. A idade dos doadores foi 58 ± 14 anos (33-85), sendo 19 (76%) masculinos e 6 (24%) femininos, 23 brancos (92%) e dois negros (8%). Os materiais foram testados em seus 10 mm centrais, com velocidade de aplicação de carga de 30 mm/min. Foi obtida a área de secção dos corpos de prova para que fossem estudadas as propriedades estruturais e materiais. Foram estudadas as seguintes variáveis: carga máxima (N), tensão(MPa), módulo de elasticidade (MPa), energia (Nm), alongamento absoluto (mm) e específico (%), limite de proporcionalidade (N), além da tensão (MPa) e alongamentos neste ponto. A análise estatística revelou que ambos possuem carga máxima, limite de proporcionalidade e tensão semelhantes (p>0,05). Nas outras variáveis ocorreu diferença significativa (p<0,05) com o tendão calcâneo apresentando valores maiores para energia e alongamento. O módulo de elasticidade, significativamente maior no ligamento da patela (p<0,05), foi a variável que melhor caracterizou a diferença do comportamento mecânico dos dois materiais.

SUBSTITUIÇÃO do LIGAMENTO da CABEÇA do FÊMUR COM AUTO-ENXERTO DE FÁSCIA LATA NA LUXAÇÃO COXOFEMORAL em CÃES

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Modified stabilization method for the tibial tuberosity advancement technique: a biomechanical study

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reconstrução do ligamento cruzado cranial em cães, associado ou não ao sulfato de condroitina

Avaliou-se o efeito da reconstrução do ligamento cruzado cranial, associado ou não ao sulfato de condroitina, na evolução da osteoartrite induzida experimentalmente em cães. Vinte cães hígidos, sem raça definida, machos e fêmeas, com peso corpóreo entre 19 e 25kg, foram submetidos à desmotomia do ligamento cruzado cranial. Trinta dias após, foram separados em dois grupos de 10 animais. Um grupo foi submetido à reconstrução do ligamento cruzado com uso de aloenxerto de ligamento patelar congelado, o outro não. Trinta e um dias após a desmotomia, cada grupo foi dividido em dois subgrupos de cinco animais. Um recebeu sulfato de condroitina, o outro não. Os cães foram avaliados clínica e radiograficamente antes da desmotomia e aos 30, 60 e 90 dias após a desmotomia. No último momento foram realizados exames macro e microscópico. Nos cães submetidos somente à desmotomia e tratados com sulfato de condroitina houve redução na progressão das alterações ósseas, ao exame radiográfico. A reconstrução do ligamento cruzado cranial melhorou a função do membro e, quando associada ao sulfato de condroitina, houve melhor resposta. Não houve diferença entre os subgrupos quanto aos exames macro e microscópico.

Alterações no líquido sinovial do joelho de cães com osteoartrite induzida pelo modelo Pond e Nuki

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação radiográfica e ultrassonográfica do aparato podotroclear de cavalos Quarto de Milha diagnosticados com síndrome do navicular

O objetivo deste estudo foi avaliar as alterações do aparato podotroclear de 22 cavalos da raça Quarto de Milha acometidos pela síndrome do navicular utilizando o acesso transcuneal. Esses equinos foram submetidos ao exame radiográfico e ultrassonográfico. No exame radiográfico foi observado a presença de invaginação sinovial de diferentes tipos, além de calcificação da bursa podotroclear e tendão flexor digital profundo, entesiófitos, osteófitos e alteração do limite córtico-medular. No exame ultrassonográfico observou-se alterações da bursa podotroclear, aderência e irregularidades nos bordos do tendão flexor digital profundo, diminuição do coxim digital, calcificação do ligamento sesamóide distal ímpar e irregularidade da superfície flexora do osso sesamóide distal. Todos os equinos que apresentavam alterações radiográficas também apresentaram alterações no exame ultrassonográfico compatíveis com a síndrome do navicular. O exame ultrassonográfico utilizando o acesso transcuneal foi um método prático e eficiente para avaliação das lesões do aparato podotroclear dos eqüinos, sendo um método complementar ao exame radiográfico.