Plasma Processing of Scaffolds for Tissue Engineering and Regenerative Medicine

Plasma processes are largely employed in the biomedical field for different kind of materials. In particular, in tissue engineering, biomaterials need to be totally integrated with biological systems in order to be employed as substitutes of artificial prostheses. Since most materials do not allow a correct integration with the biological environment, plasma processes have been demonstrated to be very versatile in altering the material surface properties in order to improve the biocompatibility of materials. The challenge is to plasma modify 3D scaffolds in order to be used for in vivo regeneration of human tissues. The correct 3D biointegration inside living tissues is the crucial objective, towards which many aspects are directed, from the material engineering to its surface modification and affinity with the biological environment. In this paper, the advances in low pressure plasma processes, applied to both 2D rigid substrates and 3D porous structures, are discussed. Further an in vivo experiment in ovine animals using plasma processed 3D scaffolds is illustrated

Pulse Pressure Variation Can Predict the Hemodynamic Response to Pneumoperitoneum in Dogs: A Retrospective Study

Pneumoperitoneum may induce important hemodynamic alterations in healthy subjects. Pulse pressure variation (PPV) is a hemodynamic parameter able to discriminate preload dependent subjects. Anesthesia records of dogs undergoing laparoscopy were retrospectively evaluated. The anesthetic protocol included acepromazine, methadone, propofol and isoflurane administered with oxygen under mechanical ventilation. The hemodynamic parameters were considered five minutes before (BASE) and ten minutes after (P10) the pneumoperitoneum. Based on the cardiac index (CI) variation, at P10, dogs were classified as sensitive (S group, CI ≤ 15%) and non-sensitive (NO-S group). Data were analyzed with the ANOVA test and the ROC curve (p < 0.05). Fifty-five percent of dogs (S) had a reduction of CI ≥ 15% at P10 (2.97 ± 1.4 L/min/m²) compared to BASE (4.32 ± 1.62 L/min/m²) and at P10 in the NO-S group (4.51 ± 1.41 L/min/m²). PPV at BASE was significantly higher in the S group (22.4% ± 6.1%) compared to the NO-S group (10.9% ± 3.3%). The ROC curve showed a threshold of PPV > 16% to distinguish the S and NO-S groups. PPV may be a valid predictor of the hemodynamic response to pneumoperitoneum in dogs. A PPV > 16% can identify patients that may require fluid administration before the creation of pneumoperitoneum

Comparison of total laparoscopic gastropexy with the Ethicon Securestrap fixation device versus knotless barbed suture in dogs

Background: This study evaluated the feasibility and efficacy of a laparoscopic absorbable fixation device (Securestrap) in total laparoscopic gastropexy in dogs susceptible to gastric dilatation-volvulus (GDV) compared to laparoscopic gastropexy performed with a barbed suture. We hypothesised that both techniques provide suitable gastropexy. Methods: The gastropexy was performed by straps (TLG-SS group, n = 6) or with a barbed suture (TLG-Vloc group, n = 6). The total surgery time, gastropexy time, the number of straps used and suture bites were recorded. Clinical and ultrasound investigations were performed during follow-up. Results: The total surgery time was 30 minutes in the TLG-SS, while it was 46.66 minutes in the TLG-Vloc. In the TLG-SS group, gastropexy time was 13 minutes, while 36.3 minutes in the TLG-Vloc. The number of straps employed in TLG-SS was 9, while seven bites were employed in TLG-Vloc. Linear regression analysis of gastropexy time versus the number of procedures was highly correlated (r2 = 0.84) in the TLG-SS. Complications, clinical and ultrasound findings did not differ between the two techniques at 90 days post-surgery. Conclusion: TLG-SS laparoscopic technique can be employed safely and effectively in less time and is associated with a relatively short learning curve, which could encourage the widespread use of prophylactic laparoscopic gastropexy

Evaluation of the Effects of Undenatured Type II Collagen (UC-II) as Compared to Robenacoxib on the Mobility Impairment Induced by Osteoarthritis in Dogs

Osteoarthritis (OA) is a chronic disease that requires a multimodal therapeutic approach. The aim of this study was to evaluate the effects of undenatured type II collagen (UC-II) as compared to robenacoxib in dogs affected by OA. Our hypothesis was that the two compounds would be similar (non-inferiority) in improving mobility. To test this hypothesis, a complete orthopedic examination, x-ray and the Liverpool Osteoarthritis in Dogs (LOAD) survey were performed in dogs affected by OA before and after the treatments. The study was designed as a clinical, randomized, controlled and prospective study. Sixty client-owned dogs were randomized in the R group (n = 30, robenacoxib 1 mg/kg/day for 30 days) and in the UC-II group (n = 30, UC-II 1 tablet/day for 30 days). Thirty days after the beginning of the treatment (T30), the dogs were reassessed for the LOAD, MOBILITY and CLINICAL scores. Based on the data obtained from the study, a significant reduction in LOAD and MOBILITY scores was recorded between T0 and T30 with a similar magnitude among the two groups (R = 31.5%, p < 0.001; UC-II = 32.7%, p = 0.013). The results of this study showed that UC-II and robenacoxib were able to similarly improve mobility of dogs affected by OA

Role of Tibial Tuberosity Fracture/Fissure through the Maquet Hole in Stifle Osteoarthritis after Porous Tibial Tuberosity Advancement in Dogs at Mid-Term Follow-Up

Tibial tuberosity advancement (TTA) is used to treat cranial cruciate ligament rupture of the stifle joint in dogs. Tibial tuberosity fracture/fissure is a complication of TTA that may have a favorable prognosis. The aim of this study was to detect how tibial tuberosity fracture/fissure through the Maquet hole worsens the progression of osteoarthritis (OA) in the stifle joint of dogs treated with porous TTA. Seventeen cases were included in the study, divided into two groups. The first group (n = 10) included subjects that had tibial tuberosity fracture/fissure through the Maquet, and the second group included subjects that had no complications (n = 7). Both groups showed significant progression compared to OA at 3 months after surgery. We observed that at T0, the control group showed a higher level of OA. For this reason, we normalized the OA scores, evaluating the percentage difference from T0 and T1. We verified that there were no statistically significant differences between the two groups. The results confirm that OA progression in subjects undergoing TTA was not significantly influenced by fracture/fissure of the tibial tuberosity through the Maquet hole. Therefore, fracture fissure through the Maquet hole should be considered as a common minor complication during TTA

Absorbable fixation straps for laparoscopic gastropexy in dogs

Objective: To evaluate the feasibility and efficacy of laparoscopic absorbable fixation straps (AFS) for laparoscopic gastropexy in dogs. Study design: Cadaveric and prospective clinical study. Animals: Five dog cadavers for the cadaveric study; 12 dogs for the clinical study. Methods: The pyloric antrum was affixed to the abdominal wall laparoscopically by applying a series of straps. The cadaveric study assessed potential challenges during the procedure and stomach mucosal penetration. For the clinical study, the total duration of surgery, time to complete the gastropexy, and the number of straps used were recorded. Ultrasound evidence of adhesion, complications, and weight were monitored at 7, 30, and 90 days after surgery. Owner satisfaction was evaluated at the 6-month follow-up. Results: The total duration of surgery was 25.8 minutes (range, 19-39; SD, 6.7), and the time to complete the gastropexy was 10.1 minutes (range, 7-19; SD, 3.9). The linear regression analysis revealed an inverse correlation between the time to complete the gastropexy and the order of the surgeries (r2 = 0.75, P <.05). No complications were recorded. Ultrasound examination was used to confirm gastropexy at all follow-ups. Conclusion: Laparoscopic gastropexy with AFS was performed in both cadavers and clinical animals with minimal complications. Persistent adhesion was demonstrated during ultrasound evaluations and in one postmortem evaluation. Clinical significance: This novel laparoscopic technique can be employed safely, effectively, and reasonably quickly, and the learning curve is expected to be relatively short

Effects of two alveolar recruitment maneuvers in an "open-lung" approach during laparoscopy in dogs

ObjectivesThe aim of this study was to compare the effects of a sustained inflation alveolar recruiting maneuver (ARM) followed by 5 cmH(2)O of PEEP and a stepwise ARM, in dogs undergoing laparoscopic surgery. Materials and methodsTwenty adult dogs were enrolled in this prospective randomized clinical study. Dogs were premedicated with methadone intramuscularly (IM); anesthesia was induced with propofol intravenously (IV) and maintained with inhaled isoflurane in pure oxygen. The baseline ventilatory setting (BVS) was as follows: tidal volume of 15 mL/kg, inspiratory pause of 25%, inspiratory to expiratory ratio of 1:2, and the respiratory rate to maintain the end-tidal carbon dioxide between 45 and 55 mmHg. 10 min after pneumoperitoneum, randomly, 10 dogs underwent sustained inflation ARM followed by 5 cmH(2)O of PEEP (ARMi), while 10 dogs underwent a stepwise recruitment maneuver followed by the setting of the "best PEEP" (ARMc). Gas exchange, respiratory system mechanics, and hemodynamic were evaluated before the pneumoperitoneum induction (BASE), 10 min after the pneumoperitoneum (PP), 10 min after the recruitment (ARM), and 10 min after the pneumoperitoneum resolution (PostPP). Statistical analysis was performed with the ANOVA test (p < 0.05). ResultsStatic compliance decreased in both groups at PP (ARMc = 1.35 +/- 0.21; ARMi = 1.16 +/- 0.26 mL/cmH(2)O/kg) compared to BASE (ARMc = 1.78 +/- 0.60; ARMi = 1.66 +/- 0.66 mL/cmH(2)O/kg) and at ARM (ARMc = 1.71 +/- 0.41; ARMi = 1.44 +/- 0.84 mL/cmH(2)O/kg) and PostPP (ARMc = 1.75 +/- 0.45; ARMi = 1.89 +/- 0.59 mL/cmH(2)O/kg), and it was higher compared to PP and similar to BASE. The PaO2/FiO(2), in both groups, was higher at ARM (ARMc = 455.11 +/- 85.90; ARMi = 505.40 +/- 31.70) and PostPP (ARMc = 521.30 +/- 66.20; ARMi = 450.90 +/- 70.60) compared to PP (ARMc = 369.53 +/- 49.31; ARMi = 394.32 +/- 37.72)