Bio-printing method as a novel approach to obtain a fibrin scaffold settled by limbal epithelial cells for corneal regeneration.

Treatment of Limbal Stem Cell Deficiency (LSCD), based on autologous transplantation of the patient's stem cells, is one of the few medical stem cell therapies approved by the European Medicines Agency (EMA). It relies on isolating and culturing in vivo Limbal Epithelial Stem Cells (LESC) and then populating them on the fibrin substrate, creating a scaffold for corneal epithelial regeneration. Such a solution is then implanted into the patient's eye. The epithelial cell culture process is specific, and its results strongly depend on the initial cell seeding density. Achieving control of the density and repeatability of the process is a desirable aim and can contribute to the success of the therapy. The study aimed to test bioprinting as a potential technique to increase the control over LESCs seeding on a scaffold and improve process reproducibility. Cells were applied to 0.5 mm thick, flat, transparent fibrin substrates using extrusion bioprinting; the control was the traditional manual application of cells using a pipette. The use of 3D printer enabled uniform coverage of the scaffold surface, and LESCs density in printed lines was close to the targeted value. Moreover, printed cells had higher cell viability than those seeded traditionally (91.1 ± 8.2% vs 82.6 ± 12.8%). The growth rate of the epithelium was higher in bioprinted samples. In both methods, the epithelium had favorable phenotypic features (p63 + and CK14 +). 3D printing constitutes a promising approach in LSCD therapy. It provides favorable conditions for LESCs growth and process reproducibility. Its application may lead to reduced cell requirements, thereby to using fewer cells on lower passages, which will contribute to preserving LESCs proliferative potential.

Computed Tomographic Findings of Dental Disease and Secondary Diseases of the Head Area in Client-Owned Domestic Rabbits (Oryctolagus cuniculus): 90 Cases.

Domestic rabbits have teeth that grow throughout the animal's life and are prone to disease. Clinical signs of dental disease in domestic rabbits are non-specific, and, therefore, a definitive diagnosis usually requires additional methods. This study was carried out on a group of 105 domestic rabbits aged 3 to 9 years. In total, 90 domestic rabbits with dental disease visible on CT images and other secondary diseases of the head area qualified for this study. Malocclusion was found in 57 (63.3%). Retrograde elongation of the tooth apices in the mandible was present in 39 (43.3%), and it was present in the maxilla in 48 (53%). Clinical tooth crowns were overgrown in 39 (43%). Dental abscesses were present in 54 (63%). Secondary to the presence of a dental abscess, osteomyelitis was found in 43 (79% of the animals with a dental abscess). Dental inflammatory resorption was found in 36 (40%). Secondary to dental disease, nasal cavity inflammation was found in 18 (20%). Otitis media was present in six (6.7%). The most common dental disease found in this study's animals was malocclusion secondary to abnormal clinical crown abrasion and abnormal tooth growth. In domestic rabbits, osteomyelitis is a common complication of dental abscesses. Computed tomography is an invaluable diagnostic method in the diagnosis of dental disease and secondary diseases of the head area, such as inflammation of the nasal cavities or otitis media, in pet rabbits.

Intraoperative parameters and postoperative follow-up of foam-based intraperitoneal chemotherapy (FBIC).

Background: For decades, intraperitoneal chemotherapy (IPC) has been delivered into the abdominal cavity as a liquid solution. Recently the concept of foam as a carrier-solution for IPC was suggested. This in-vivo swine study aims to evaluate the safety, intraoperative parameters, limitations and postoperative complications of foam-based intraperitoneal chemotherapy (FBIC). Methods: Three 65-day-old swine received FBIC with doxorubicin in a laparoscopy setting. Intraoperative parameters were monitored throughout the procedure and an extensive postoperative laboratory monitoring was conducted for 7 days. At day seven an autopsy was performed for further evaluation. Results: The insufflation of FBIC caused a temporary rise in blood pressure and a simultaneous drop in heart rate. Capnography detected a continuous increase in end-tital CO2 levels. A temporary drop of intraabdominal temperature was noted. Postoperative blood and serum laboratory results did not indicate any organ failure. No indication of intraperitoneal infections was noted and no structural tissue changes were visible in the autopsy. Discussion: The application of FBIC appears to be a feasible approach regarding intraoperative anesthesiology and postoperative surgical management. A lack of postoperative structural changes on the seventh day were a promising sign of safety and biocompatibility. Surgical reintervention would have been possible. To discuss a possible clinical application, further studies are required to investigate long-term safety, pharmacodynamics and the antitumoral potential of FBIC.

Laparoscopic ureteroneocystostomy in the treatment of urinary incontinence due to ectopy of the ureters in female dogs: A pilot study.

Ureteral ectopia is rare and requires surgical treatment after a thorough diagnostic workup. Open surgical techniques for repositioning ectopic ureters have been known for many years and are well described in the literature. However, to the best of our knowledge, no laparoscopic method of correcting this pathology has been described, which, in our opinion, would benefit the animal in terms of the healing process and overall clinical outcomes. This study aimed to evaluate the possibility of laparoscopic treatment of ureteral ectopia, which causes urinary incontinence in dogs. All of the operated ten dogs presented in this study were client-owned females with symptoms of urinary incontinence due to a unilateral intramural ectopic ureter. A three-trocar laparoscopic technique was used to perform the ureteroneocystostomy of the ectopic ureter. In this article, clinicopathological data, imaging features, procedural findings, complications, and short- and long-term outcomes are presented. The procedure was feasible in all cases. No major postoperative complications were observed. Among the minor complications, slight hematuria was observed in three dogs, which resolved spontaneously. In the period of at least one year after surgery, no negative impact of the procedure was observed. Seven of the ten operated dogs regained urinary continence. The remaining three dogs required additional surgery (urethral bulking) because of a lack of improvement after adjuvant pharmacological treatment. Overall, good-to-excellent long-term outcomes can be achieved; however, dogs that remain incontinent after laparoscopic ureteroneocystostomy may require additional treatment.

Drug Distribution and Penetration of Foam-Based Intraperitoneal Chemotherapy (FBIC).

For decades, intraperitoneal chemotherapy (IPC) was used as a liquid solution for the treatment of peritoneal metastasis. Due to its advantageous physical properties, foam-based intraperitoneal chemotherapy (FBIC) was recently proposed as a treatment for peritoneal metastasis. For the first time, this study intends to examine the feasibility, expansion, drug distribution, and penetration of FBIC in vivo. Three swine received contrast-enhanced FBIC doxorubicin delivered using a bicarbonate carrier system. During the procedure, intraoperative blood analyses and periumbilical diameter, as well as foam distribution, penetration, and expansion of the FBIC were analyzed. The swine received an abdominal CT scan to evaluate the contrast distribution. Furthermore, a hematoxylin-eosin (HE) staining of peritoneal samples was performed, and fluorescence microscopy was conducted. FBIC was performed without complications. The periumbilical diameter peaked after 5 min and then decreased. Blood analyses showed changes in blood parameters, with a reduction in the pH levels of serum calcium and potassium. CT scan detected contrast-enhanced FBIC throughout the abdominal cavity. Fluorescence microscopy confirmed that all areas were exposed to doxorubicin and no pathologies were detected in the HE histology. Our preliminary results are quite encouraging and indicate that FBIC is a feasible approach. However, in order to discuss possible clinical applications, further studies are required to investigate the pharmacologic, pharmacodynamic, and physical properties of FBIC.

Preliminary study on fluid bolus administration for prevention of spinal hypotension in dogs undergoing elective cesarean section.

Introduction: This study aimed to investigate the effect of fluid bolus administration during epidural anesthesia (coload) in female dogs scheduled for elective cesarean section (CS). Hypotension is one of the most common complications of epidural (EA) and spinal (SA) analgesia, and in the case of cesarean section, it may pose a significant risk for placental perfusion and subsequent fetal vitality and puppy survival. Methods: Pregnant bitches scheduled for elective CS underwent EA with (treatment group) or without (control group) intravenous fluid bolus administration. The following parameters were measured and compared between both groups: HR, RR, etCO2, SpO2, systolic, diastolic and mean arterial blood pressure were measured at three time points (T1: before surgery, T2: after the last puppy removal, and T3: end of surgery) in dams; vitality (Apgar score at 0, 5, and 20 min) and umbilical cord blood parameters (pH, pCO2, HCO3, base excess, lactate and glucose) in newborns. Results: The results indicated that crystalloid coloading increased maternal systolic, diastolic, and mean blood pressure (treatment vs. control group, 101.46 ± 9.18, 48.01 ± 13.47, and 67.07 ± 13.15 mmHg vs. 80.68 ± 7.29, 36.52 ± 8.75, and 180 52.30 ± 7.77, p < 0.05) with significantly fewer episodes of hypotension. Additionally, puppies in the treatment group received higher scores in the 5-min (7.91 ± 1.67 vs. 6.74 ± 2.20) and 20-min (9.38 ± 0.87 vs. 8.39 ± 2.50) assessments without the favorable effect on umbilical blood gas parameters. Discussion: Based on the obtained results, it can be stated that crystalloid coload offers an effective option in cases of hypotension during cesarean section, with clear benefits for both mothers and newborns.

A Novel Surgical Hybrid Approach to Neoplastic Lesions in the Distal Part of the Urethra: A Pilot Series of Clinical Cases.

All the surgical approaches described to date for the removal of distal urethral tumors have some technical difficulties that make these tumors difficult to treat. The article presents for the first time the treatment results of three female dogs, diagnosed with transitional cell carcinomas of the distal urethra, operated with a newly developed hybrid surgical method-a combination of laparoscopy and open surgery. This technique uses vulvovaginectomy, combined with resection of the distal urethra and prepubic urethrostomy. All of the procedures were possible to perform, without the need to carry out a laparotomy conversion. Histopathology revealed transitional cell carcinoma in all cases, with a margin of healthy tissues maintained in two out of three cases, which meant reoperation of the urethrostomy site in the remaining one case. The mean survival time was nine months. Among minor complications, recurrent cystitis was found. After the first surgery, all dogs retained full control over urination immediately after recovery from anesthesia. In one case that required reoperation, complete urinary incontinence occurred after the second procedure. The present findings suggest that hybrid surgery can be used to treat distal urethral tumors. Qualification for surgery must be limited to bitches with tumors of the distal urethra and without metastases, without the possibility of using other surgical methods, and with the owner's full acceptance of the risk of complications.

Comparison of 2 anesthetic protocols and surgical timing during cesarean section on neonatal vitality and umbilical cord blood parameters.

BACKGROUND: The objective of this study was to evaluate the relationship between the mode of anesthesia, the time form the induction to the extraction of a puppy and the immediate postnatal vitality and umbilical cord blood gases parameters in cesarean section derived-puppies. Two different anesthetic protocols were used: inhalation using isoflurane (ISO) and combined-inhalation and epidural (EPI) with propofol being the induction agent. RESULTS: Significant differences were found in ISO group in pH values, pCO2 levels and Apgar scores between puppies at different extraction times (< 30 vs. ≥ 30 min). In ISO group puppies extracted later were more acidic (7.16 vs. 7.22), had higher levels of pCO2 (69 vs. 57 mmHg) and lower Apgar scores at birth (1.2 vs. 2.5). On the contrary, in EPI group no differences were observed between the delivery time, umbilical blood gas parameters and puppies' vitality. Furthermore, the dams from the EPI group required lower concentrations of isoflurane (MAC 1.11 ± 0.19 vs.1.37 ± 0.16, p < 0.001). CONCLUSIONS: Multiple pregnancies frequent in dogs lead to significant differences in extraction times between the first and the last puppy during cesarean section. Obtained results showed that the mode of anesthesia and the surgical time would influence the neonatal outcome during cesarean section in dogs. The higher concentration of isoflurane with the longer time of exposure had a negative effect on the initial newborn vitality as well as the umbilical cord blood gas parameters. Therefore, when performing CS in giant dog breeds or expecting many puppies in the litter, it is worth considering epidural component that allow for lower concentrations of inhalant agents, which may contribute to a better clinical condition of newborns.

A Case Series of 11 Horses Diagnosed with Bone Spavin Treated with High Intensity Laser Therapy (HILT).

The aim of this work was to characterize and describe the effect of High Intensity Laser Therapy (HILT) used in the treatment of chronic osteoarthritis in horses. Over a 2 year period, 11 horses with diagnosed bone spavin were treated with HILT as a monotherapy. The horses chosen for this report presented hind limb lameness, were positive in a spavin flexion test and showed improvement after intra-articular anesthesia of the tarsometatarsal joint. Additionally, all the horses presented radiological signs of tarsus osteoarthritis and had not been treated for bone spavin for a minimum of 6 months. Each horse received 10 HILT therapies over 14 days' treatment time with the same laser protocol. At post-treatment orthopedic examination, 4 horses (36%) had improved 2 lameness grades (in the 5 grade American Association of Equine practitioners lameness scale), 4 horses (36%) had improved 1 lameness grade and 3 horses (28%) did not improve. Additionally, 3 horses were totally sound after HILT. Post-treatment spavin test result improvement was observed in 5 horses (45%), and 6 horses (55%) showed the same spavin test grade as before treatment. There were no horses that were sound in the spavin test performed after HILT. Therefore, it seems probable that the application of HILT in horses suffering from bone spavin may decrease joint pain, which influences visual lameness reduction.

First In Vivo Applicational Data of Foam-Based Intrathoracic Chemotherapy (FBiTC) in a Swine Model.

BACKGROUND: For decades, both intraperitoneal and pleural chemotherapy (IPC) have been delivered as a liquid solution. Recent studies suggest that foam carriers outperform liquid carriers for locoregional chemotherapy. For the first time, this study aims to evaluate the feasibility, safety, and characteristics of foam-based intrathoracic chemotherapy (FBiTC) in an in vivo setting. METHODS: In this study, contrast-enhanced FBiTC with doxorubicin was delivered via video-assisted thoracoscopy (VAT) in three swine under general anesthesia. Intraoperative and postoperative parameters, blood analyses, vital signs, and anesthesiologic data were collected. Additionally, an intraoperative computer tomography (CT) scan was performed, and histological tissue sections were collected and further analyzed using fluorescence microscopy. RESULTS: FBiTC was delivered without major complications. End-tidal capnometry detected increased CO2 levels with reduced peripheral oxygen saturation and increased blood pressure and heart rate. No major intra- or postoperative complications were observed. CT scans confirmed a multidirectional distribution pattern of foam. Postoperative laboratory workup did not reveal any critical changes in hemoglobin, white blood count, or platelets. There was no evidence of critical kidney impairment or liver function. Fluorescence microscopy of tissue specimen detected doxorubicin in pleural tissues. DISCUSSION: Our preliminary results are encouraging and indicate that FBiTC is feasible. However, to consider a possible clinical application, further studies are required to investigate the pharmacologic, pharmacodynamic, and physical properties of FBiTC and to ensure the safety of the overall procedure regarding oxygenation levels and capnography parameters.

Evaluating the concept of gas­based intraperitoneal hyperthermia beyond 43˚C in the treatment of peritoneal metastasis: A pilot study.

While hyperthermic intraperitoneal applications have demonstrated high efficacy in treating peritoneal metastases (PM), these applications are limited to temperatures of 41-43˚C to prevent a harmful increase in core temperature. However, since gaseous substances display low specific heat capacities, gas-based hyperthermia could potentially increase surface temperatures without affecting the body's core temperature. To the best of our knowledge, the present study is the first to explore the in vivo feasibility of gas-based hyperthermia via spatial and time-based distribution. In the present study, a temperature-isolated, abdominal box model was created with fresh peritoneal tissue exposed to continuous high-volume airflow temperatures ranging between 47 and 69˚C. Heat conduction within the peritoneal tissues was measured using temperature microsensors. Temperature build-up at different time points during the procedure was calculated and the safest option to perform gas-based intraperitoneal hyperthermia beyond 43˚C was identified using an in vivo swine model. In subsequent experiments, viability and cytotoxicity of HT-29 colon cancer cells were measured following short-term hyperthermia. The present study demonstrated that the application of gas-based intraperitoneal hyperthermia with temperatures up to 50˚C is possible without increasing the core temperature to harmful levels. Gas-based intraperitoneal hyperthermia can induce a histological reaction on the peritoneal surface, and it can also result in decreased viability and increased cytotoxicity of HT-29 cells. The concept of extreme hyperthermia may be of great clinical importance as it could significantly increase local cytotoxicity in PM without increasing the body's core temperature. Further studies are required to investigate the benefits, as well as the restrictions, of this novel concept.

Osteogenic Potential of Sheep Mesenchymal Stem Cells Preconditioned with BMP-2 and FGF-2 and Seeded on an nHAP-Coated PCL/HAP/ß-TCP Scaffold.

Mesenchymal stem cells (MSCs) attract interest in regenerative medicine for their potential application in bone regeneration. However, direct transplantation of cells into damaged tissue is not efficient enough to regenerate large bone defects. This problem could be solved with a biocompatible scaffold. Consequently, bone tissue engineering constructs based on biomaterial scaffolds, MSCs, and osteogenic cytokines are promising tools for bone regeneration. The aim of this study was to evaluate the effect of FGF-2 and BMP-2 on the osteogenic potential of ovine bone marrow-derived MSCs seeded onto an nHAP-coated PCL/HAP/ß-TCP scaffold in vitro and its in vivo biocompatibility in a sheep model. In vitro analysis revealed that cells preconditioned with FGF-2 and BMP-2 showed a better capacity to adhere and proliferate on the scaffold than untreated cells. BM-MSCs cultured in an osteogenic medium supplemented with FGF-2 and BMP-2 had the highest osteogenic differentiation potential, as assessed based on Alizarin Red S staining and ALP activity. qRT-PCR analysis showed increased expression of osteogenic marker genes in FGF-2- and BMP-2-treated BM-MSCs. Our pilot in vivo research showed that the implantation of an nHAP-coated PCL/HAP/ß-TCP scaffold with BM-MSCs preconditioned with FGF-2 and BMP-2 did not have an adverse effect in the sheep mandibular region and induced bone regeneration. The biocompatibility of the implanted scaffold-BM-MSC construct with sheep tissues was confirmed by the expression of early (collagen type I) and late (osteocalcin) osteogenic proteins and a lack of an elevated level of proinflammatory cytokines. These findings suggest that FGF-2 and BMP-2 enhance the osteogenic differentiation potential of MSCs grown on a scaffold, and that such a tissue engineering construct may be used to regenerate large bone defects.

Safety, feasibility, and application of intraperitoneal gas-based hyperthermia beyond 43°C in the treatment of peritoneal metastasis: An in-vivo pilot study.

Background: 43°Celsius (C) is currently the highest temperature used in the treatment of peritoneal metastasis (PM). Despite sufficient data on water- based hyperthermic solutions in PM treatment, there is currently no information on gas-based hyperthermia extending beyond 43°C. This study is the first to provide in-vivo data on different organ systems during and after intraperitoneal gas-based hyperthermia beyond 43°C. The aim of this study is to explore in-vivo feasibility, safety, and efficacy of this novel concept from a biological perspective. Methods: For this study, three swine were subjected to laparoscopy and subsequent gas-based intraperitoneal hyperthermia at 48°, 49° and 50°C under a high-flow air stream. Intraoperative data from multiple temperature sensors were analysed. Additionally, intraoperative anaesthesiologic and gasometrical data was analysed. Postoperatively, swine were monitored for one week and laboratory work-up was performed on postoperative days 1, 3 and 7. Results: During gas-based intraperitoneal hyperthermia, anesthesiologic parameters did not exhibit critical values. No intra- or postoperative complications were observed. Distinct temperature measurements on the skin, cystohepatic triangle and esophagus did not display any temperature increase. Postoperative laboratory workup did not show any changes in hemoglobin, white blood cell count, platelets, or kidney function. Discussion: Based on our data, there are no safety concerns for the application of gas-based hyperthermia between 48 - 50°C. In fact, no critical systemic temperature increase was observed. With respect to possible limitations, further in-vivo studies are required to evaluate whether gas-based intraperitoneal hyperthermia may be a therapeutic option for PM patients.

In-vivo thermodynamic exploration of gas-based intraperitoneal hyperthermia.

Background: While hyperthermic intraperitoneal (i.p) applications are highly efficient in treating peritoneal metastases (PM), they are currently limited to temperatures of 41 - 43° Celsius (C). First data on gas-based i.p. hyperthermia is promising, as this novel method allows a significant temperature rise in superficial peritoneal layers without increasing core temperatures. Until now, key mechanisms of this novel tool, e.g. thermodynamic energy transfer, have not been investigated. This study aims to explore the volume of thermodynamic energy transfer during gas-based i.p. hyperthermia at 48-50°C and its peritoneal effects. Methods: For this study, three swine were subjected to gas-based i.p. hyperthermia at varying temperatures (48°, 49° and 50°C) in a diagnostic laparoscopy setting with a high-flow air stream. Temperatures of the i.p. cavity, in- and outflow airstream at the trocar were measured and the thermodynamic energy transfer was calculated. Tissue samples were collected on postoperative day 7 for histopathologic analyses. Results: According to our data, temperatures within the intraabdominal cavity and at the outflow site remain relatively stable at < 40°C. An increase in thermodynamic energy transfer is observed with increasing applied temperatures. Gas-based i.p. hyperthermia induced capillary coagulation and white blood cell infiltration within peritoneal layers. Conclusions: Gas-based i.p. hyperthermia is an innovative approach which enables the i.p. delivery of specific amounts of thermodynamic energy. Following this procedure, our data indicate remarkable histologic changes on the superficial peritoneal layer most likely attributable to the applied thermodynamic energy. Further studies are required to investigate how these findings can be applied in PM management.

The Onset of In-Vivo Dehydration in Gas -Based Intraperitoneal Hyperthermia and Its Cytotoxic Effects on Colon Cancer Cells.

Background: Peritoneal metastasis (PM) is an ongoing challenge in surgical oncology. Current therapeutic options, including intravenous and intraperitoneal (i.p.) chemotherapies display limited clinical efficacy, resulting in an overall poor prognosis in affected patients. Combined hyperthermia and dehydration induced by a high-flow, gas-based i.p. hyperthermic procedure could be a novel approach in PM treatment. Our study is the first to evaluate the therapeutic potential of i.p. dehydration, hyperthermia, as well as the combination of both mechanisms in an in-vivo setting. Methods: For this study, three swine were subjected to diagnostic laparoscopy under a high-flow air stream at 48°, 49° and 50°Celsius (C). Hygrometry of the in- and outflow airstream was measured to calculate surface evaporation and i.p. dehydration. To analyze the effects of this concept, in vitro colon cancer cells (HT-29) were treated with hyperthermia and dehydration. Cytotoxicity and cell viability were measured at different time intervals. Additionally, structural changes of dehydrated cells were analyzed using scanning electron microscopy. Results: According to our results, both dehydration and hyperthermia were cytotoxic to HT-29 cells. However, while dehydration reduced cell viability, hyperthermia did not. However, dehydration effects on cell viability were significantly increased when combined with hyperthermia (p<0.01). Conclusions: Changes to the physiological milieu of the peritoneal cavity could significantly reduce PM. Therefore, limited dehydration of the abdominal cavity might be a feasible, additional tool in PM treatment. Further studies are required to investigate dehydration effects and their applicability in PM management.

Reduction of greenhouse gases emission through the use of tiletamine and zolazepam.

Isoflurane is an anaesthetic gas widely used in both human and veterinary medicine. All currently used volatile anaesthetics are ozone-depleting halogenated compounds. The use of total intravenous anaesthesia (TIVA) allows to induce the effect of general anaesthesia by administering drugs only intravenously without the use of anaesthetic gases. This allows you to create a protocol that is safe not only for the patient, but also for doctors and the environment. However, so far, no anaesthetic protocol based on induction of anaesthesia with tiletamine-zolazepam without the need to maintain anaesthesia with anaesthetic gas has been developed. Our study showed that the use of this combination of drugs for induction does not require the use of additional isoflurane to maintain anaesthesia. Thanks to Dixon's up-and-down method we proved that with the induction of anaesthesia with tiletamine-zolazepam at a dose of 5 mg/kg the use of isoflurane is not needed to maintain anaesthesia in minimally invasive surgical procedures. Until now, this dose has been recommended by the producer for more diagnostic than surgical procedures or for induction of general anaesthesia. The maintenance was required with anaesthetic gas or administration of another dose of the tiletamine-zolazepam. The results obtained in this study will allow for a significant reduction in the consumption of isoflurane, a gas co-responsible for the deepening of the greenhouse effect, having a negative impact on patients and surgeons. These results are certainly the first step to achieving a well-balanced and safe TIVA-based anaesthetic protocol using tiletamine-zolazepam, the obvious goal of which will be to maximize both the safety of the patient, people involved in surgical procedures, and the environment itself. Being aware of the problem of the greenhouse effect, we are committed to reducing the consumption of anaesthetic gases by replacing them with infusion agents.

Indirectly assessing changes in corneal properties with OCT speckle after crosslinking in porcine eyes.

The aim of this study was to assess the effect of the standard crosslinking (CXL) procedure on corneal properties and subsequent changes in collagen bonds formation using optical coherence tomography (OCT) corneal speckle statistics and vibrational spectroscopy. Porcine eyes with intact corneal epithelium were randomly selected to one of the four study groups: (1) untreated eyes moistened with phosphate-buffered saline (PBS); (2) eyes after the epithelial debridement and riboflavin application; (3) eyes after CXL procedure according to the Dresden protocol; and (4) eyes after corneal epithelial debridement, regularly moistened with PBS. Before and after this selection, each eyeball was subjected to the constant intraocular pressure of 20 mmHg. Then, ocular biometry was performed and the central cornea was imaged using spectral-domain OCT. Following this, a nonparametric approach to speckle modeling (the Contrast Ratio (CR)) was utilized within the region of interest for each B-scan covering the central corneal stroma. To verify whether the CXL performed ex-vivo results in formation of new bonds in the cornea, Fourier Transform Infrared Attenuated Total Reflectance (ATR-FTIR) spectra of dried corneas, dissected from examined eyeballs, were collected and analyzed. Corneal epithelium removal alone or with the riboflavin application leads to a statistically significant decrease in the CR median value (the Wilcoxon signed-rank test, p < 0.05). However, the most pronounced change in CR median value, which decreases with the increased number of scatterers, was shown after the complete CXL procedure including riboflavin soaking and UVA irradiation (the Wilcoxon signed-rank test, p = 0.004). Analysis of ATR-FTIR spectra revealed influence of UVA irradiation on collagen matrix. The study has shown the increased dehydration accompanied by almost no alteration of collagen native triple-helical structure. Significant changes have been observed for bands related to collagen crosslinks. Specifically, the predominant changes occurred in the sugar region from 1150 to 975 cm-1, as well as in the absorbance of carbonyl groups. Furthermore, the ratio of two Amide I components at approximately 1660 cm-1 and 1675 cm-1 decreased after UVA irradiation. Together, these results provided the evidence for the creation of new corneal crosslinks. In conclusion, this study clearly indicates that the UVA exposure causes the substantial difference in optical scattering occurring in corneal stroma as a result of the induced biochemical changes at the molecular level in this tissue assessed with ATR-FTIR. The proposed speckle-based methodology brings a new insight into the development of OCT technology useful in an indirect assessment of some collagen changes.

Clinical Usefulness of the Anaesthetic Protocol Using Low Doses of Tiletamine - Zolazepam Combination in Continuous Rate Infusion as a Partial Intravenous Anaesthesia in Bitches Undergoing Laparoscopic Surgery.

The objective of this study was to evaluate the clinical usefulness of the combination of tiletamine-zolazepam used in low doses as a continuous rate infusion in a partial intravenous anesthesia protocol. Fifteen clinically healthy, different breed bitches weighing 25.08 ± 10.39 kg was used in this study. After a food fast for at least 12 hours and water fast for 4 hours, the animals were premedicated with dexmedetomidine. After 15 minutes, the bolus of tiletamine-zolazepam combination was given as an. Induction of general anesthesia, immediately followed by continuous intravenous infusion. The following parameters were measured immediately after the induction of general anesthesia and lasted until the end of the surgery: electrocardiography, heart rate, systolic arterial blood pressure, diastolic arterial blood pressure, mean arterial blood pressure, body temperature respiratory rate end tidal of CO2. During the recovery period, pain level was evaluated as well as sedation assessment. Time for successful intubation after administration of the tiletamine-zolazepam combination was within 3 minutes. Heart rate was within reference values. Systolic, diastolic, and mean arterial blood pressure were also within the reference values. Internal body temperature showed a downward trend for a whole procedure time. During recovery, only 1 patient showed symptoms of pain and signs of dissociation. In summary, the partial intravenous protocol with the use of tiletamine-zolazepam combination and low anesthetic gases concentration is clinically useful because of ensuring the correct level of anesthesia and stability of intraoperative parameters as well as a good recovery period.

Novel surgical approach to neoplastic lesions in the distal part of the urethra: A pilot cadaver study comparing open and hybrid techniques.

Tumours of the distal urethra in female dogs are often difficult to treat, and the surgical methods described thus far have technical limitations. This study aimed to present a novel approach to the surgical treatment of distal urethral tumours. This study used dog cadavers to evaluate the technical feasibility of surgically removing neoplastic lesions in the distal urethra and compared surgical outcomes of open surgery with those of hybrid surgery (combination of laparoscopy and open surgery). Open intact, open spayed, hybrid intact, and hybrid spayed dog cadaver groups underwent surgery (n = 6 per group). The novel surgical method was based on vulvovaginectomy (ovariohysterectomy in intact dogs), resection of the distal part of the urethra, and pre-pubic urethrostomy. Outcomes of interest included technical feasibility of each procedure, using both surgical techniques, wound length, time required to complete the procedure, and the incidence of intraoperative ureter and rectum injuries. Surgical technique and reproductive status affected operating time. Technique choice affected wound length; the surgical wound was longer in the open group than in the hybrid group. Macroscopic evaluation of the rectum did not reveal any damage to the wall. There was no evidence of ureter leakage or obstruction in any case. The present findings suggest that both open and hybrid surgery can be used to treat distal urethral tumours.

Parameters of Hemostasis in Sheep Implanted with Composite Scaffold Settled by Stimulated Mesenchymal Stem Cells-Evaluation of the Animal Model.

Implantation of composite scaffolds could be potentially associated with the risk of hemostatic disturbances in a recipient. However, there is a lack of information on possible alterations in clotting mechanisms resulting from such a procedure. The aim of the present work was to investigate changes in hemostatic parameters in sheep implanted with a scaffold composed of poly(ε-caprolactone) and hydroxyapatite and tricalcium phosphate (9:4.5:4.5), settled previously with mesenchymal stem cells stimulated by fibroblast growth factor-2 and bone morphogenetic protein-2. Nine Merino sheep were examined for 7 days, and measurements of clotting times (PT, aPTT), activities of antithrombin, protein C and clotting factors II-XII, and concentrations of fibrinogen and D-dimer were carried out before and 1 h, 24 h, 3 days and 7 days after scaffold implantation. The introduction of scaffold initially resulted in a slowdown of the clotting processes (most evident 24 h after surgery); PT and aPTT increased to 14.8 s and 33.9 s, respectively. From the third day onwards, most of these alterations began to return to normal values. The concentration of fibrinogen rose throughout the observation period (up to 8.4 g/L), mirroring the ongoing inflammatory reaction. However, no signals of significant disturbances in hemostatic processes were detected in the sheep tested.