Effects of intra-articular hyaluronic acid on ex vivo responses by third carpal bone cartilage from horses with experimentally induced synovitis

2004 ◽  
Vol 1 (2) ◽  
pp. 119-129 ◽  
Author(s):  
Jan L Palmer ◽  
Joseph Mansour ◽  
Charles J Malemud ◽  
Alicia L Bertone

AbstractWe studied the extent to which intra-articular hyaluronic acid (HA) administered to horses with experimentally induced synovitis in the third middle carpal joint altered cartilage proteoglycans (PGs) and the biomechanical properties of the third carpal bone. Intra-articular HA (Hylartin-V®) was administered to the middle carpal joints of healthy horses before and after the induction of synovitis by Escherichia coli lipopolysaccharide (LPS). Two groups of horses received intra-articular HA only, with evaluation 2 and 6 weeks later (group 2 and group 4). Two other groups (group 1 and group 3) received LPS followed by intra-articular HA and evaluation 2 and 6 weeks later. Ex vivo third carpal bone cartilage PG synthesis was measured by 35SO4 incorporation and third carpal bone cartilage PG content was determined by an assay for glucuronic acid. Biomechanical properties were measured by indentation testing. At the 2-week evaluation, HA did not ablate the quantitative reduction in PG synthesis and PG content in animals with experimental synovitis. However, by 6 weeks, there was a significant rebound effect in that PG synthesis and PG content were elevated in horses with experimental synovitis that had received intra-articular HA, compared with horses that had received HA only for that period of time. There were also alterations in the gel filtration profiles of newly synthesized PGs on Sepharose CL-2B among the groups. However, there were no de novo PG species associated with any of the treatments. Furthermore, we found that the biomechanical properties of third carpal bone cartilage were not altered in any of the groups. These studies showed that intra-articular HA administered to horses with experimentally induced synovitis did not provide short-term (i.e. 2-week) benefit to third carpal bone cartilage PG synthesis. However, a long-term benefit of intra-articular HA may occur after the acute effects of synovitis on PG synthesis and PG content subside.

2009 ◽  
Vol 54 (No. 1) ◽  
pp. 33-40 ◽  
Author(s):  
A. Sagliyan ◽  
E. Karabulut ◽  
E. Unsaldi ◽  
I. Yaman

The present study examined the results of using hyaluronic acid with autogenetic cancellous grafts in the treatment of experimentally induced osteochondral defects in the stifle joints of dogs. In this study, 10 mature dogs of different breeds, weights and of both sexes were used. General anesthesia and usual operation procedures were followed. A 10 mm deep defect was created on the femoral sulcus of the trochlea with a drill tip of 8 mm in diameter. The defects in the right and left legs were filled with autogenic cancellous grafts taken from the metaphysial region of the tibia. The left legs constituted the experimental group while the right legs served as control group. In the experimental group, 2 mg/kg intraarticular hyaluronic acid was twice administered into the stifle joint, i.e., immediately subsequent to the operation and 1 month afterwards. Parenteral antibiotics were prescribed postoperatively for ten days. Five animals were sacrificed at the third and sixth month after surgery. Macroscopic and microscopic findings obtained from each case were evaluated. On macroscopical examination, trochlear defects were determined to be incompletely filled at the third month in both control and experimental groups. On histopathologic examination, a loose fibrovascular formation in the area where the graft was applied was observed to be present in both control and experimental groups. However, in the experimental group this formation was more superficial, ossification activity was greater and trabeculous bone formation had been initiated. Macroscopical examination carried out in the sixth month determined that in the control group the defect surface did not fill up to the trochlear sulcus level. In the histopathologic examination, in control groups it was found that fibrocartilageous structures were developing in the fibrovascular space even though ossification was incomplete. The macroscopic examination showed that in the experimental group, the defect surface reached the trochlear sulcus level of defects in this month. The histopatologic examination revealed that fibrous tissue comprised a thin layer, under which ossification processes were complete and bone trabeculates fully formed. It was concluded that the usage of autogenic cancellous graft along with hyaluronic acid may be useful in the repair of large osteochondral defects.


2020 ◽  
Vol 90 (6) ◽  
pp. 637-642
Author(s):  
Petar Kostešić ◽  
◽  
Mirta Vučković ◽  
Janoš Kodvanj ◽  
Martin Šurjak ◽  
...  

The transcostal closure technique of intercostal thoracotomy closure appears to be associated with less pain in the first 24 hours and could be an alternative to the standard circumcostal technique. The goal of this study was to compare the ex vivo biomechanical properties of three suture techniques for intercostal thoracotomy closure. Samples of porcine ribs were used for the research. A 10 cm incision was made in the intercostal space in each sample. The techniques compared were: simple circumcostal interrupted suturing, continuous circumcostal suturing, and interrupted transcostal suturing. During the testing in the machine, suture rupture or rib cracking occurred. If rib cracking occurred first, the testing was continued until the suture broke as well. In the first group, rib fracture occurrence was 60% and suture rupture was 40%. In the second group, rib fracture occurrence was 55%, while 45% of the samples failed by suture rupture. In the third group, rib fracture occurrence was 70%, while suture rupture was 30%. These data did not differ significantly between groups (P>0.05). Continuous circumcostal suturing took the least amount of time, and the most time-consuming technique was interrupted transcostal suturing. Simple circumcostal suturing used most material, and the least amount of material was used with continuous circumcostal suturing. The conclusion of this paper is that the continuous pattern suture has the same mechanical strength as the other two suture patterns, but it consumes the least time and material. Therefore, from a mechanical standpoint, we advise the use of continuous circumcostal suture for intercostal thoracotomy closure.


Author(s):  
E.J. Prendiville ◽  
S. Laliberté Verdon ◽  
K. E. Gould ◽  
K. Ramberg ◽  
R. J. Connolly ◽  
...  

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.


1989 ◽  
Vol 02 (03) ◽  
pp. 125-128
Author(s):  
E. M. Gaughan ◽  
N. G. Duchar

SummaryImplant associated fractures have not been reported in horses. Two horses were evaluated for fractures in the fore limbs, occurring subsequent to previous fracture repair. Previously, the horses had sustained fractures of unusual configurations which were repaired using internal fixation. Following repair and healing of the fractures, secondary fractures occurred in the same bone, but in a different (more common) configuration. The first horse was evaluated ten months following lag screw fixation of a longitudinal fracture of the proximal phalanx in a frontal plane. This horse presented with a more typical comminuted fracture in the sagittal plane with the screws from the first fixation lying in the fracture line. This fracture was successfully treated with a cast. The second horse was examined eightteen months after repair of a medial sagittal slab fracture of the third carpal bone. The horse presented with a more typical dorsal slab fracture of the third carpal bone with the previously placed lag screw lying in the fracture line. The screw was removed and a lag screw was placed perpendicular to the new fracture plane through the dorsal surface of the third carpal bone to repair the fracture.


2021 ◽  
Vol 22 (2) ◽  
pp. 674
Author(s):  
Óscar Darío García-García ◽  
Marwa El Soury ◽  
David González-Quevedo ◽  
David Sánchez-Porras ◽  
Jesús Chato-Astrain ◽  
...  

Acellular nerve allografts (ANGs) represent a promising alternative in nerve repair. Our aim is to improve the structural and biomechanical properties of biocompatible Sondell (SD) and Roosens (RS) based ANGs using genipin (GP) as a crosslinker agent ex vivo. The impact of two concentrations of GP (0.10% and 0.25%) on Wistar rat sciatic nerve-derived ANGs was assessed at the histological, biomechanical, and biocompatibility levels. Histology confirmed the differences between SD and RS procedures, but not remarkable changes were induced by GP, which helped to preserve the nerve histological pattern. Tensile test revealed that GP enhanced the biomechanical properties of SD and RS ANGs, being the crosslinked RS ANGs more comparable to the native nerves used as control. The evaluation of the ANGs biocompatibility conducted with adipose-derived mesenchymal stem cells cultured within the ANGs confirmed a high degree of biocompatibility in all ANGs, especially in RS and RS-GP 0.10% ANGs. Finally, this study demonstrates that the use of GP could be an efficient alternative to improve the biomechanical properties of ANGs with a slight impact on the biocompatibility and histological pattern. For these reasons, we hypothesize that our novel crosslinked ANGs could be a suitable alternative for future in vivo preclinical studies.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ádám László Nagy ◽  
Zsolt Tóth ◽  
Tamás Tarjányi ◽  
Nándor Tamás Práger ◽  
Zoltán Lajos Baráth

Abstract Background In this research the biomechanical properties of a bone model was examined. Porcine ribs are used as experimental model. The objective of this research was to investigate and compare the biomechanical properties of the bone model before and after implant placement. Methods The bone samples were divided in three groups, Group 1 where ALL-ON-FOUR protocol was used during pre-drilling and placing the implants, Group 2 where ALL-ON-FOUR protocol was used during pre-drilling, and implants were not placed, and Group 3 consisting of intact bones served as a control group. Static and dynamic loading was applied for examining the model samples. Kruskal–Wallis statistical test and as a post-hoc test Mann–Whitney U test was performed to analyze experimental results. Results According to the results of the static loading, there was no significant difference between the implanted and original ribs, however, the toughness values of the bones decreased largely on account of predrilling the bones. The analysis of dynamic fatigue measurements by Kruskal–Wallis test showed significant differences between the intact and predrilled bones. Conclusion The pre-drilled bone was much weaker in both static and dynamic tests than the natural or implanted specimens. According to the results of the dynamic tests and after a certain loading cycle the implanted samples behaved the same way as the control samples, which suggests that implantation have stabilized the skeletal bone structure.


Author(s):  
Inmaculada Méndez ◽  
Juan Pedro Martínez-Ramón ◽  
Cecilia Ruiz-Esteban ◽  
José Manuel García-Fernández

Burnout is a reality in the teaching profession. Specifically, teaching staff usually have higher burnout rates. The present study aims to analyze the different burnout profiles and to verify if there were differences between burnout profiles in depressive symptomatology and in the self-esteem of the teachers at school. The total number of participants was 210 teachers from 30 to 65 years. The first scale was the Maslach burnout inventory, the second scale was the Self-Rating depression scale and the third scale was the Rosenberg Self-Esteem Scale. The latent class analysis identified three burnout profiles: the first group with a high level of emotional exhaustion, low personal accomplishment and depersonalization (high burnout); the second group with low emotional exhaustion, low depersonalization and high personal accomplishment (low burnout) and the third group with low depersonalization, low emotional exhaustion and low personal accomplishment (moderate burnout). The results revealed that there were differences in depressive symptomatology (group 1 obtained higher scores than group 2 and group 3) and self-esteem (group 2 obtained higher scores than group 1). The psychological balance and health of teachers depend on preventing the factors that have been associated with this syndrome.


2010 ◽  
Vol 36 (5) ◽  
pp. 441-446 ◽  
Author(s):  
B. J. HOPPER ◽  
C. STEEL ◽  
J. L. RICHARDSON ◽  
G. R. ALEXANDER ◽  
I. D. ROBERTSON

2013 ◽  
Vol 135 (10) ◽  
Author(s):  
Clare Y. L. Chao ◽  
Gabriel Y. F. Ng ◽  
Kwok-Kuen Cheung ◽  
Yong-Ping Zheng ◽  
Li-Ke Wang ◽  
...  

An evaluation of wound mechanics is crucial in reflecting the wound healing status. The present study examined the biomechanical properties of healing rat skin wounds in vivo and ex vivo. Thirty male Sprague-Dawley rats, each with a 6 mm full-thickness circular punch biopsied wound at both posterior hind limbs were used. The mechanical stiffness at both the central and margins of the wound was measured repeatedly in five rats over the same wound sites to monitor the longitudinal changes over time of before wounding, and on days 0, 3, 7, 10, 14, and 21 after wounding in vivo by using an optical coherence tomography-based air-jet indentation system. Five rats were euthanized at each time point, and the biomechanical properties of the wound tissues were assessed ex vivo using a tensiometer. At the central wound bed region, the stiffness measured by the air-jet system increased significantly from day 0 (17.2%), peaked at day 7 (208.3%), and then decreased progressively until day 21 (40.2%) as compared with baseline prewounding status. The biomechanical parameters of the skin wound samples measured by the tensiometer showed a marked reduction upon wounding, then increased with time (all p < 0.05). On day 21, the ultimate tensile strength of the skin wound tissue approached 50% of the normal skin; while the stiffness of tissue recovered at a faster rate, reaching 97% of its prewounded state. Our results suggested that it took less time for healing wound tissues to recover their stiffness than their maximal strength in rat skin. The stiffness of wound tissues measured by air-jet could be an indicator for monitoring wound healing and contraction.


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