Josip Kos

Biological repair of thyroid cartilage defects by osteogenic protein-1 (bone morphogenetic protein-7) in dog.

The efficacy of human recombinant osteogenic protein-1 (OP-1; bone morphogenetic protein-7) in regeneration of dog larynx was examined by treating thyroid cartilage defects (1.5 cm2) in dogs with thyroid allografts covered with host perichondrium or fascia. Prior to implantation allografts were frozen, thawed and demineralized. The treatment groups were as follows: I - Allograft control implant (n = 3); II - Implants coated with 500 μg OP-1 (n = 4); III - Implants coated with 100 μg OP-1 (n = 3); IV - Implants coated with 500 μg OP-1 and covered with neck fascia (n = 3); and V - Implants extracted with 1M NaCl and guanidine hydrochloride, and coated with 500 μg OP-1 (n = 4). Dogs were sacrificed four months following surgery. Each larynx was removed, carefully dissected and a three-dimensional reconstruction of the defect area was performed on serial sections. The results revealed that the implants of control dogs remained intact with no apparent reduction in size and new tissue formation. OP-1 enriched thyroid allografts, dose dependently induced bone, cartilage and ligament-like structures comprising up to 80% of the total regenerated defect area. Boundaries of the defects healed by formation of new bone when bone resided within the old thyroid cartilage layers. Old cartilage not containing bone within its layers healed by complete integration with newly formed cartilage. Both new bone and cartilage were embedded into layers of new ligament-like tissue which expressed specific morphologic and molecular markers. The three newly formed tissues were tightly connected into a “bone-cartilage-ligament continuum” of tissues, suggesting that OP-1 served as a multiple tissue morphogen in this specific microenvironment.

Aminotransferases after experimental pneumoperitoneum in dogs.

Background:  Laparoscopic surgery has rapidly become a popular and widely used technique. Elevated intra abdominal pressure due to gas insufflation for laparoscopic surgery may result in a number of local and systemic effects on the organism. The effects of pneumoperitoneum on the cardiovascular and respiratory system are well known today, but very few studies have been carried out on the consequences of pneumoperitoneum on hepatic integrity. The aim of the present study was to assess changes in aminotransferases, bilirubin and prothrombin time after pneumoperitoneum in dogs.

Comparison of the Effects of Low Intra-Abdominal Pressure and Pentoxifylline on Oxidative Stress during CO2 Pneumoperitoneum in Rabbits

Background: The aim of this study was to investigate the effect of low-pressure pneumoperitoneum and pentoxifylline, a methylxanthine derivative, in the prevention of injury caused by free oxygen radicals generated during CO2 pneumoperitoneum. Methods: Twenty-eight rabbits were allocated randomly to 4 groups. Control group rabbits (group 1) were subjected to anesthesia for 60 min; group 2 and 3 animals were subjected to a CO2 pneumoperitoneum (15 or 7 mm Hg); and group 4 rabbits received 50 mg/kg pentoxifylline, followed by a 15-mm-Hg pneumoperitoneum. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), lipid hydroperoxide, glutathione reductase and total antioxidant status were measured. Results: Compared with group 1, a significant increase in lipid hydroperoxide levels at the end of the pneumoperitoneum and 30 min after deflation and a significant decrease in total antioxidant status 24 h after deflation were recorded in group 2. In addition, a significant increase was observed in ALT, AST and LDH levels. These changes were attenuated by low-pressure pneumoperitoneum, whereas pentoxifylline pretreatment appeared to attenuate only transaminase levels. Conclusion: Low-pressure pneumoperitoneum could attenuate ischemia/reperfusion injury induced by CO2 pneumoperitoneum in a rabbit model whereas pentoxifylline pretreatment appeared to attenuate only transaminase levels. Pentoxifylline did not prevent the development of oxidative stress.

Bull castration by method of total scrotal ablation

In this work, a 2 years and 10 months old bull, with 14 days history of wound on the right side of scrotum was presented. A painful swelling coated by grayish pseudo membranes of necrotic epithelium and fibrin was observed in right lateroventral portion of the scrotum. The presented data enabled us to make decision of performing the total scrotal ablation. The intention was to prevent the influence of probable resorbed necrotic tissue on the vital status of the patient.

Osteosynthesis of the radius and ulna in a brown hare lepus europeus

Six months old brown hare was presented at the Surgery Clinic for evaluation of a right forelimb third grade lameness. Full physical examination, blood samples for complete blood count, and serum biochemistry were performed. Radiographic examination from anteroposterior and lateral views confirmed a old, closed, complete, non-comminuted, transverse fracture in the middle part of right radius and ulna. Fracture repair in the brown hare is a similar to those in cats and dogs. Stabilization of fractures with bone plates and screws are the most popular methods of fracture fixation. Osteosynthesis was performed by 2.0, 8-hole stainless steel Synthes dynamic compression plate, DCP (Synthes Holding AG, 4500 Solothurn, Switzerland) placed on radius in neutral position to achieve anatomical repositioning of fragments and to restore normal biological function of the limb. Surgical procedure was performed within 45 minutes in order to reduce residence in a hospital environment, which hares generally find stressful. The fracture was assessed as clinically stable in the 5th day postoperatively and the animal was weightbearing on its forelimb. Osteosynthesis of hare radius using DCP plate 2.0 is a good method of fixation and healing fractures. After performing full clinical examination and bloodwork, controled and modulated anaesthesia and analgesia, it is possible to perform osteosynthesis with excellent outcome and also a good way to preserve fragile wildlife.

The effect of preanesthetic administration of lactated ringer solution on blood pressure in isoflurane-anesthetized horses.

Hypotension induced by volatile agents is particularly notorious in horses and it is probably one of the major causes of the high anaesthetic risk in this species. In the present study we investigated the influence of 10 mL/kg lactated Ringer solution on the values of arterial blood pressure during the elective surgical procedure, administered right before the induction of anaesthesia. The goal was to establish if it was possible to lower the risk of hypotension development with this type of therapy. Nine horses divided in two groups were used in this study. All the horses were submitted to the same anesthetic regimen. The second group of horses received 10 mL/kg i.v. lactated Ringer solution in the 15 minutes time before the induction of anesthesia. The effect of lactated Ringer solution was noted at the beginning of anesthesia. Statistically significant differences among groups were noticed during the first measurement. The results indicate that the suggested method may provide a very simple way of supporting the cardiovascular system at least at the beginning of the surgical procedure.