CONTRIBUTION TO THE STUDY OF THE MECHANISM OF ACTION OF A2-ADRENERGIC AGONISTS ON THE RESPIRATORY SYSTEM IN SHEEP.

ΔΙΕΡΕΥΝΑΤΑΙ Η ΘΕΣΗ ΚΑΙ Ο ΜΗΧΑΝΙΣΜΟΣ ΔΡΑΣΗΣ ΤΩΝ Α2-ΑΔΡΕΝΕΡΓΙΚΩΝ ΑΓΩΝΙΣΤΩΝ ΣΤΗΝ ΠΡΟΚΛΗΣΗ ΥΠΟΞΑΙΜΙΑΣ, ΑΝΑΠΝΕΥΣΤΙΚΗΣ ΔΥΣΧΕΡΕΙΑΣ ΚΑΙ ΥΠΕΡΚΑΠΝΙΑΣ ΣΤΟ ΠΡΟΒΑΤΟ. ΜΕΛΕΤΗΘΗΚΕ Η ΕΠΙΔΡΑΣΗ ΤΗΣ ΞΥΛΑΖΙΝΗΣ ΤΟΥ ST-91, ΤΗΣ ΑΤΙΠΑΜΕΖΟΛΗΣ, ΤΗΣ ΜΙΔΑΓΛΙΖΟΛΗΣ, ΤΗΣ ΑΤΡΟΠΙΝΗΣ, ΤΗΣ Α ΣΠΙΡΙΝΗΣ, ΤΗΣ ΠΡΟΣΤΑΚΥΚΛΙΝΗΣ ΚΑΙ ΕΠΙΛΕΓΜΕΝΩΝ ΣΥΝΔΥΑΣΜΩΝ ΤΟΥΣ ΧΟΡΗΓΟΥΜΕΝΩΝ ΕΝΔΟΦΛΕΒΙΩΣ ΚΑΙ ΕΝΤΟΣ ΜΙΑΣ ΠΛΑΓΙΑΣ ΚΟΙΛΙΑΣ ΤΟΥ ΕΓΚΕΦΑΛΟΥ, ΣΤΟΥΣ ΧΑΡΑΚΤΗΡΕΣ ΤΗΣ ΑΝΑΠΝΟΗΣ, ΣΤΑ ΑΕΡΙΑ ΤΟΥ ΑΡΤΗΡΙΑΚΟΥ ΑΙΜΑΤΟΣ, ΣΤΗΝ ΟΞΕΟΒΑΣΙΚΗ ΙΣΟΡΡΟΠΙΑ ΚΑΙ ΣΤΟΝ ΚΟΡΕΣΜΟ ΤΗΣ ΑΙΜΟΣΦΑΙΡΙΝΗ Σ ΣΕ ΟΞΥΓΟΝΟ ΣΤΟ ΑΡΤΗΡΙΑΚΟ ΑΙΜΑΚΑΙ ΣΤΟΝ ΑΡΙΘΜΟ ΚΑΙ ΣΤΗ ΣΥΣΣΩΡΕΥΣΗ ΤΩΝ ΑΙΜΟΠΕΤΑΛΙΩΝ. ΣΧΕΤΙΚΑ ΜΕ ΤΗ ΘΕΣΗ ΔΡΑΣΗΣ ΤΩΝ Α2-ΑΔΡΕΝΕΡΓΙΚΩΝ ΑΓΩΝΙΣΤΩΝ ΠΡΟΚΥΠΤΕΙ ΟΤΙ ΑΥΤΟΙ ΔΡΟΥΝ ΚΥΡΙΩΣ ΠΕΡΙΦΕΡΙΚΑ, ΤΟΥΛΑΧΙΣΤΟΝ ΓΙΑ ΤΗΝ ΠΡΟΚΛΗΣΗ ΤΗΣ ΥΠΟΞΑΙΜΙΑΣ, ΚΑΙ ΠΑΡΑΛΛΗΛΑ ΣΕ ΜΙΚΡΟ ΒΑ ΘΜΟ ΚΕΝΤΡΙΚΑ. Η ΚΕΝΤΡΙΚΗ ΔΡΑΣΗ ΤΟΣ, ΠΙΘΑΝΩΣ, ΠΡΟΚΑΛΕΙ ΣΥΣΠΑΣΗ ΤΩΝ ΑΕΡΑΓΩΓΩΝ ΜΕΣΩ ΚΕΤΝΡΙΚΗ ΔΙΕΓΕΡΣΗΣΗ ΤΟΥ ΠΑΡΑΣΥΜΠΑΘΗΤΙΚΟΥ ΣΥΣΤΗΜΑΤΟΣ. ΣΤΟΥΣ ΜΗΧΑΝΙΣΜΟΥΣ ΠΕΡΙΦΕΡΙΚΗΣΔΡΑΣΗΣ ΤΟΥΣ ΣΥΜΠΕΡΙΛΑΜΒΑΝΕΤΑΙ Η ΣΥΣΣΩΡΕΥΣΗ ΤΩΝ ΑΙΜΟΠΕΤΑΛΙΩΝ ΣΤΑ ΤΡΙΧΟΕΙΔΗ ΤΗΣΠΝΕΥΜΟΝΙΚΗΣ ΚΥ ΚΛΟΦΟΡΙΑΣ, Η ΟΠΟΙΑ ΟΜΩΣ ΣΥΜΜΕΤΕΧΕΙ ΣΕ ΜΙΚΡΟ ΜΟΝΟ ΒΑΘΜΟ ΣΤΗΝ ΕΜΦΑΝΙΣΗ ΤΩΝ ΑΝΑΠΝΕΥΤΙΚΩΝ ΕΚΔΗΛΩΣΕΩΝ

Comparison between the Effect of Lidocaine or Ropivacaine Hematoma Block and of Different Timings of Administration on Post-Operative Pain in Dogs Undergoing Osteosynthesis of Long-Bone Fractures

Objective: We aimed to compare the efficacy of intra-operative lidocaine hematoma block (HB) to ropivacaine HB and to compare the efficacy of different timings of ropivacaine HB in controlling post-operative pain in dogs undergoing the osteosynthesis of long-bone fractures. Study Design: We conducted a randomized, blinded, prospective clinical study. Animals: Forty-eight dogs with long-bone fractures were included and were randomly allocated to four groups: lidocaine (L), ropivacaine (Rmid), ropivacaine pre- (Rpre) and ropivacaine post- (Rpost) groups. Methods: The dogs in group L (n = 14) and in group Rmid (n = 11) received a lidocaine or ropivacaine HB, respectively, after fracture reduction and before osteosynthesis material placement. Rpre dogs (n = 11) received ropivacaine HB before fracture reduction, and Rpost dogs (n = 12) received ropivacaine HB after osteosynthesis material placement. Eight post-operative pain assessments were performed using the University of Melbourne Pain Scale (UMPS) and an algometer. Rescue analgesia was administered based on UMPS scoring. For data analysis, the Shapiro–Wilk test of normality, chi-square, Student t test and Split Plot analysis were used. The level of significance was set at α = 0.05. Results: Rescue analgesia was administered to one dog in group L, one in group Rmid and one in group Rpost, with no significant differences detected. Compared to group Rmid, group L dogs exhibited significantly higher mean mechanical pain thresholds (p = 0.049) and lower mean UMPS scores (p = 0.001). Group Rpost dogs had statistically significantly higher mean pain thresholds compared to group Rmid (p = 0.009). Clinical Implications: When performed after fracture reduction and before osteosynthesis material placement, lidocaine HB seems to be more effective than ropivacaine HB in controlling post-operative pain in dogs undergoing osteosynthesis of long-bone fractures. The administration of ropivacaine HB after osteosynthesis material placement seems to be more effective than administration after fracture reduction and before osteosynthesis material placement or administration before fracture reduction in controlling post-operative pain in dogs undergoing osteosynthesis of long-bone fractures

A Controlled Trial of Polyglytone 6211 versus Poliglecaprone 25 for Use in Intradermal Suturing in Dogs

The objective of this work was the comparative evaluation of the healing process after employing 4/0 poliglecaprone 25 and 4/0 polyglytone 6211 in a continuous intradermal suture pattern. Ten Beagle dogs were used, in which skin incisions were created surgically and subsequently were sutured by means of continuous intradermal pattern using polyglytone 6211 or poliglecaprone 25 suture. Cosmetic, clinical, and histologic scores were evaluated. The cosmetic appearance of the wounds was blindly evaluated on days 7, 14, 28, 180, 360, 730, and 1095. On the same days, tissue biopsy was performed for histological evaluation. Clinical evaluation was performed initially daily, then weekly, monthly, and finally yearly, till day 1095. The clinical appearance of the intradermal pattern with both sutures was initially very good, deteriorated in the second post-operative month and thereafter improved. The cosmetic, clinical, and histological differences between the two suture materials were minimal and statistically insignificant. Polyglytone 6211 is sufficient for use in intradermal suturing in dogs. However, its earlier absorption compared to poliglecaprone 25 did not have any beneficial effect on cutaneous wound healing and scar appearance in the experimental animals

A Controlled Trial of Polyglytone 6211 versus Poliglecaprone 25 for Use in Intradermal Suturing in Dogs

The objective of this work was the comparative evaluation of the healing process after employing 4/0 poliglecaprone 25 and 4/0 polyglytone 6211 in a continuous intradermal suture pattern. Ten Beagle dogs were used, in which skin incisions were created surgically and subsequently were sutured by means of continuous intradermal pattern using polyglytone 6211 or poliglecaprone 25 suture. Cosmetic, clinical, and histologic scores were evaluated. The cosmetic appearance of the wounds was blindly evaluated on days 7, 14, 28, 180, 360, 730, and 1095. On the same days, tissue biopsy was performed for histological evaluation. Clinical evaluation was performed initially daily, then weekly, monthly, and finally yearly, till day 1095. The clinical appearance of the intradermal pattern with both sutures was initially very good, deteriorated in the second post-operative month and thereafter improved. The cosmetic, clinical, and histological differences between the two suture materials were minimal and statistically insignificant. Polyglytone 6211 is sufficient for use in intradermal suturing in dogs. However, its earlier absorption compared to poliglecaprone 25 did not have any beneficial effect on cutaneous wound healing and scar appearance in the experimental animals

Vaginal rupture and evisceration in a dog

A 1.5-year-old German Shepherd mixed breed dog was admitted with mild haemorrhage from the vulva and a perineal mass of 24-hour duration, which had been first observed immediately after parturition. Parturition had occurred at low ambient temperature, and only one puppy survived out of the seven oversized fetuses. The dog was in poor body condition, dehydrated, hypothermic, depressed, non-ambulatory and in a state of shock. Intestinal loops, the urinary bladder and the uterine horns and body were protruding from the vulva. A true vaginal prolapse was also observed. The abdominal viscera were flushed with warm sterile saline solution, protected and maintained wet. The laboratory findings included moderate anaemia, leukocytosis, hypoalbuminaemia, azotaemia and elevated liver enzyme activities. Stabilisation of the dog’s general condition was attempted before surgery. Antimicrobial and analgesic drugs were also administered. After exploratory laparotomy the protruding organs, which were in good condition, were reduced. A recent rupture in the vaginal wall, approximately 6 cm long, was observed. Ovariohysterectomy and partial vaginectomy were performed. The preoperative course of therapy was continued, but the bitch died 12 hours later. The probable cause of vaginal rupture and evisceration in this bitch was tenesmus and/or trauma due to the oversized fetuses

Benign esophageal stricture in the dog and cat: A retrospective study of 20 cases

Twenty animals with benign esophageal strictures are presented. Most of the esophageal strictures were thought to be related to gastroesophageal reflux during ovariohysterectomy and were located at the distal portion of the thoracic esophagus (caudal to the base of the heart). For the dilation procedure, the endoscope tip or a balloon catheter was used and the outcome was generally considered to be good. The endoscope tip was an adequate instrument for dilation in some cases

The Effect of the Preoperative Fasting Regimen on the Incidence of Gastro-Oesophageal Reflux in 90 Dogs

This study aimed to investigate the effect of three different preoperative fasting regimens on the incidence of gastro-oesophageal reflux (GOR) in dogs under general anaesthesia. Ninety dogs undergoing non-abdominal and non-thoracic elective surgery were included in the study and equally allocated to three groups. Dogs received canned food providing half the daily resting energy requirements (RER) 3 h prior to premedication (group 3H), a quarter of the daily RER 3 h before premedication (group 3Q), and half the daily RER 12 h before premedication (group 12H). The animals were premedicated with acepromazine and pethidine, anaesthesia was induced with propofol and maintained with isoflurane vaporised in oxygen. Oesophageal pH was monitored throughout anaesthesia. Demographic and surgery-related parameters were not different among groups. The incidence of GOR was 11/30 in group 3H (36.7%), 9/30 in group 3Q (30.0%) and 5/30 in group 12H (16.7%), which was not statistically different (p = 0.262). Reduction of the amount of the preoperative meal from half to a quarter of the daily RER did not reduce the incidence of GOR but resulted in a lower oesophageal pH (p = 0.003). The results of this study suggest that the administration of a meal 3 h before anaesthesia does not have any beneficial effect in the reduction of GOR incidence in dogs compared to the administration of a meal 12 h before anaesthesia

Allogeneic Serum and Macromolecular Crowding Maintain Native Equine Tenocyte Function in Culture

The absence of a native extracellular matrix and the use of xenogeneic sera are often associated with rapid tenocyte function losses during in vitro culture. Herein, we assessed the influence of different sera (equine serum and foetal bovine serum) on equine tenocyte morphology, viability, metabolic activity, proliferation and protein synthesis as a function of tissue-specific extracellular matrix deposition (induced via macromolecular crowding), aging (passages 3, 6, 9) and time in culture (days 3, 5, 7). In comparison to cells at passage 3, at day 3, in foetal bovine serum and without macromolecular crowding (traditional equine tenocyte culture), the highest number of significantly decreased readouts were observed for cells in foetal bovine serum, at passage 3, at day 5 and day 7 and without macromolecular crowding. Again, in comparison to traditional equine tenocyte culture, the highest number of significantly increased readouts were observed for cells in equine serum, at passage 3 and passage 6, at day 7 and with macromolecular crowding. Our data advocate the use of an allogeneic serum and tissue-specific extracellular matrix for effective expansion of equine tenocytes

The Effect of the Preoperative Fasting Regimen on the Incidence of Gastro-Oesophageal Reflux in 90 Dogs

This study aimed to investigate the effect of three different preoperative fasting regimens on the incidence of gastro-oesophageal reflux (GOR) in dogs under general anaesthesia. Ninety dogs undergoing non-abdominal and non-thoracic elective surgery were included in the study and equally allocated to three groups. Dogs received canned food providing half the daily resting energy requirements (RER) 3 h prior to premedication (group 3H), a quarter of the daily RER 3 h before premedication (group 3Q), and half the daily RER 12 h before premedication (group 12H). The animals were premedicated with acepromazine and pethidine, anaesthesia was induced with propofol and maintained with isoflurane vaporised in oxygen. Oesophageal pH was monitored throughout anaesthesia. Demographic and surgery-related parameters were not different among groups. The incidence of GOR was 11/30 in group 3H (36.7%), 9/30 in group 3Q (30.0%) and 5/30 in group 12H (16.7%), which was not statistically different (p = 0.262). Reduction of the amount of the preoperative meal from half to a quarter of the daily RER did not reduce the incidence of GOR but resulted in a lower oesophageal pH (p = 0.003). The results of this study suggest that the administration of a meal 3 h before anaesthesia does not have any beneficial effect in the reduction of GOR incidence in dogs compared to the administration of a meal 12 h before anaesthesia

Hyaluronic Acid as Macromolecular Crowder in Equine Adipose-Derived Stem Cell Cultures

The use of macromolecular crowding in the development of extracellular matrix-rich cell-assembled tissue equivalents is continuously gaining pace in regenerative engineering. Despite the significant advancements in the field, the optimal macromolecular crowder still remains elusive. Herein, the physicochemical properties of different concentrations of different molecular weights hyaluronic acid (HA) and their influence on equine adipose-derived stem cell cultures were assessed. Within the different concentrations and molecular weight HAs, the 10 mg/mL 100 kDa and 500 kDa HAs exhibited the highest negative charge and hydrodynamic radius, and the 10 mg/mL 100 kDa HA exhibited the lowest polydispersity index and the highest % fraction volume occupancy. Although HA had the potential to act as a macromolecular crowding agent, it did not outperform carrageenan and Ficoll®, the most widely used macromolecular crowding molecules, in enhanced and accelerated collagen I, collagen III and collagen IV deposition