Vascular Remodeling of Clinically Used Patches and Decellularized Pericardial Matrices Recellularized with Autologous or Allogeneic Cells in a Porcine Carotid Artery Model.

Background: Cardiovascular surgery is confronted by a lack of suitable materials for patch repair. Acellular animal tissues serve as an abundant source of promising biomaterials. The aim of our study was to explore the bio-integration of decellularized or recellularized pericardial matrices in vivo. Methods: Porcine (allograft) and ovine (heterograft, xenograft) pericardia were decellularized using 1% sodium dodecyl sulfate ((1) Allo-decel and (2) Xeno-decel). We used two cell types for pressure-stimulated recellularization in a bioreactor: autologous adipose tissue-derived stromal cells (ASCs) isolated from subcutaneous fat of pigs ((3) Allo-ASC and (4) Xeno-ASC) and allogeneic Wharton's jelly mesenchymal stem cells (WJCs) ((5) Allo-WJC and (6) Xeno-WJC). These six experimental patches were implanted in porcine carotid arteries for one month. For comparison, we also implanted six types of control patches, namely, arterial or venous autografts, expanded polytetrafluoroethylene (ePTFE Propaten® Gore®), polyethylene terephthalate (PET Vascutek®), chemically stabilized bovine pericardium (XenoSure®), and detoxified porcine pericardium (BioIntegral® NoReact®). The grafts were evaluated through the use of flowmetry, angiography, and histological examination. Results: All grafts were well-integrated and patent with no signs of thrombosis, stenosis, or aneurysm. A histological analysis revealed that the arterial autograft resembled a native artery. All other control and experimental patches developed neo-adventitial inflammation (NAI) and neo-intimal hyperplasia (NIH), and the endothelial lining was present. NAI and NIH were most prominent on XenoSure® and Xeno-decel and least prominent on NoReact®. In xenografts, the degree of NIH developed in the following order: Xeno-decel > Xeno-ASC > Xeno-WJC. NAI and patch resorption increased in Allo-ASC and Xeno-ASC and decreased in Allo-WJC and Xeno-WJC. Conclusions: In our setting, pre-implant seeding with ASC or WJC had a modest impact on vascular patch remodeling. However, ASC increased the neo-adventitial inflammatory reaction and patch resorption, suggesting accelerated remodeling. WJC mitigated this response, as well as neo-intimal hyperplasia on xenografts, suggesting immunomodulatory properties.

Live Birth Following Uterine Transplantation From a Nulliparous Deceased Donor.

BACKGROUND: Nulliparous uterine grafts have never been used in uterus transplantation (UTx), possibly due to presumed infertility. Our objective was to verify the feasibility of nulliparous uterine graft transplantation. METHODS: The Czech Uterus Transplant Trial (registered under ClinicalTrials.gov, identifier NCT03277430) is a 2-arm trial comparing the efficacy of deceased donor (DD) versus live-donor uterus transplant (10 patients in both arms). A 25-year-old patient suffering from inborn absolute uterine factor infertility underwent a DD uterus transplant. The donor was a 20-year-old nulliparous brain-dead donor. RESULTS: The transplant procedure was uneventful. The posttransplant period was complicated by (1) recurrent episodes of acute cellular rejection, (2) neutropenia necessitating the administration of granulocyte colony-stimulating factor, (3) vaginal anastomotic stenosis treated with the insertion of a self-expanding stent, (4) the concurrence of Clostridium difficile colitis and acute appendicitis, and (5) temporary renal function impairment of a combined cause. Two years after the UTx, after the fourth embryo transfer, the patient became pregnant. Apart from gestational diabetes mellitus, the pregnancy was uneventful. Due to preterm contractions, delivery was achieved via caesarean section at gestational age 34 + 6 years. The postoperative course was uneventful for both the mother and the newborn. CONCLUSIONS: Herein, we report the first live birth after a DD UTx in Europe. This report provides a proof of concept that nulliparous uteri may present a suitable source of uterine grafts for UTx. Stenting may serve as a feasible treatment method for vaginal anastomotic stenosis.

Hybrid Repair Combined with Fresh Arterial Allograft Extra-Anatomical Reconstruction: The Treatment of Infrarenal Abdominal Aneurysm above an Aortobifemoral Bypass Complicated by an Infected Pseudoaneurysm in the Left Groin.

INTRODUCTION: A 72-year-old male patient was admitted into our centre with large infected pseudoaneurysm (PSA) in the left groin. The patient underwent a CT angiography (CTA) that confirmed a large partly thrombosed 6.5 × 5.5 cm PSA in the left groin arising from the distal anastomosis of the aortobifemoral bypass (ABF). Furthermore, the CTA revealed 11 cm juxtarenal abdominal aortic aneurysm (JAAA) from which the proximal anastomosis of the ABF was arising. METHOD: Aorto-uni-iliac stent graft Cook was placed from the right groin trough native severely stenotic right iliac arteries with proximal landing zone below the renal arteries, excluding the JAAA and the ABF. The distal landing zone was in the common iliac artery maintaining patent right internal iliac artery. Afterwards, a femoro-femoral crossover bypass from right to left was performed using a fresh arterial allograft. Postprocedurally, the hospital stay was uneventful. The left groin PSA cultures came positive for Staphylococcus epidermidis and Corynebacterium tuberculostearicum, both sensitive to vancomycin and rifampicin. RESULT: The patient underwent intravenous ATB treatment with vancomycin for two weeks, followed by four weeks of oral rifampicin. The patient was discharged on the 20th postoperative days. CONCLUSION: Hybrid repair combining aortic stent graft and extra-anatomical bypass in the treatment of infected distal parts of an aortofemoral bypass is an acceptable treatment modality.

The Effect of Different Thawing Rates on Cryopreserved Human Iliac Arteries Allograft's Structural Damage and Mechanical Properties.

INTRODUCTION: The rate of thawing of cryopreserved human iliac arteries allografts (CHIAA) directly affects the severeness of structural changes that occur during this process. METHOD: The experiment was performed on ten CHIAA. The 10% dimethylsulphoxide in 6% hydroxyethyl starch solution was used as the cryoprotectant; all CHIAA were cooled at a controlled rate and stored in the vapor phase of liquid nitrogen (-194°C). Two thawing protocols were tested: (1) placing the CHIAA in a water bath at 37°C, and (2) the CHIAA were thawed in a controlled environment at 5°C. All samples underwent analysis under a scanning electron microscope. Testing of the mechanical properties of the CHIAA was evaluated on a custom-built single axis strain testing machine. Longitudinal and circumferential samples were prepared from each tested CHIAA. RESULTS: Ultrastructural analysis revealed that all five CHIAA thawed during the thawing protocol 1 which showed significantly more damage to the subendothelial structures when compared to the samples thawed in protocol 2. Mechanical properties: Thawing protocol 1-longitudinal UTS 2, 53 ± 0, 47 MPa at relative strain 1, 27 ± 0, 12 and circumferential UTS 1, 94 ± 0, 27 MPa at relative strain 1, 33 ± 0, 09. Thawing protocol 2-longitudinal ultimate tensile strain (UTS) 2, 42 ± 0, 34 MPa at relative strain 1, 32 ± 0, 09 and circumferential UTS 1, 98 ± 0, 26 MPa at relative strain 1, 29 ± 0, 07. Comparing UTS showed no statistical difference between thawing methods. CONCLUSION: Despite the significant differences in structural changes of presented thawing protocols, the ultimate tensile strain showed no statistical difference between thawing methods.

Human uterine vasculature with respect to uterus transplantation: A comprehensive review.

Due to the novelty of uterus transplantation, data on preferable inflow and outflow of the graft are limited. This paper reviews the technique, type of vessels and the outcome. A systematic search of the PubMed database was conducted. We extracted and analyzed data on the arteries and veins utilized, types of anastomosis, types of donors, complications and the outcome. Thirty eight sources reported 51 human uterine transplantations, 10 graft thromboses and 25 live births. Inflow was established with two uterine arteries (UA) with/without the anterior division of the internal iliac artery in 62% (n = 31) of cases, two UA arteries with a segment/patch of the internal iliac artery in 34% (n = 17) of cases or two UA with a conduit in 4% of cases (n = 2). Both cases with a conduit developed thrombosis (n = 2). Arterial thrombosis/ischemia developed in 8 of the 51 cases. In 50% of cases with arterial thrombosis, atherosclerosis was identified as a possible cause. Outflow was established by two internal iliac veins with patches/segments in 27.5% of cases (n = 14) followed by two utero-ovarian veins in 25.5% (n = 13). Venous thrombosis occurred in 3 of the 51 cases. Uterine arteries with/without anterior division of the internal iliac artery were the most frequent arteries used for inflow and produced the highest patency rate. The presence of atherosclerosis and complex arterial reconstruction was associated with a high rate of arterial thrombosis. None of the veins utilized in the procedures appeared to be superior. There are insufficient data to draw a definite conclusion.

Matrix Vaginal Rings for Female Dogs-Effect of Altering Dimensions on Mechanical Properties and Dissolution Characteristics, and In vivo Safety Study.

The vaginal rings research is almost exclusively focused on rings for human medicine, although the dosage form offers improvement of therapeutic effect in other mammals as well. This contribution studied an effect of varying dimension parameters (diameter 20, 30 or 40 mm; height 3, 4 or 5 mm; width of annulus 5, 7.5 or 10 mm) on mechanical properties and dissolution behaviour of silicone vaginal rings with constant drug amount, intended for use in dogs. Results showed that altering dimensions influenced mechanical properties (compressive force, tensile strength and resistance of removal thread), in vitro drug release and water uptake. The removal thread resistance was increasing with increasing height and width. Compression force was higher for the rings with smaller diameter. The total drug release was increasing with decreasing height and rising diameter, surface area and water uptake during dissolution test. The initial dissolution rate was slower for the rings with higher width. As the best candidate for use in model dog subjects, the ring with 30 mm diameter, 3 mm height and 7.5 mm width was found. These drug-free vaginal rings were further tested in in vivo safety study. The results did not show any major deviation from the physiological conditions. Graphical abstract.

Effect of GnRH agonist deslorelin implant on spermatogenesis and testosterone concentration in Guinea pigs (Cavia aperea porcellus).

Guinea pigs are social animals that are often kept in groups regardless of their gender. Due to reproduction control and male aggressiveness prevention, surgical castration is commonly required. In the present study, we evaluated the effect of GnRH agonist implant (4.7 mg deslorelinum) on the serum testosterone concentration (T) and spermatogenesis in male guinea pigs. Twenty-four animals were divided into two groups. All animals in the first group were neutered (Group 1), animals in the second group (Group 2) were administered the implant subcutaneously and then neutered in one-month intervals. A histological examination was performed when cross sections of seminiferous tubules were assessed. Subsequently, these tubules were divided based on the most developed germ cell observed: spermatogonia, spermatocytes, round spermatids, elongating spermatids and elongated spermatids. The anticipated decrease in testosterone concentration and cessation of spermatogenesis was not achieved. Thus, the results obtained proved the inefficacy of the deslorelin implant in male guinea pigs so the alternative methods of contraception remain the methods of choice.

Correction to: Interventional Radiological Treatment of Pediatric Liver Transplantation Complications.

In the original article, the following author name was incorrectly published and the corrected name is given below.

Interventional Radiological Treatment of Paediatric Liver Transplantation Complications.

PURPOSE: To assess the efficacy of percutaneous techniques in managing paediatric liver transplantation complications. MATERIAL AND METHODS: We carried out 105 paediatric cadaveric donor liver transplantations at our centre from 2001 to 2018. Percutaneous techniques were used to treat 25 cases involving transplantation complications in 23 patients. Biliary complications were treated in 14 cases (13.3%): 10 patients had bile duct obstruction, and 4 had biliary leaks. Vascular complications were treated in 11 cases (10.5%): 5 hepatic artery (HA) stenoses/occlusions, 2 inferior vena cava (IVC) stenoses, and 1 portal vein (PV) stenosis. Other interventions involved embolisation of the superior mesenteric artery branch to manage gastrointestinal bleeding in 2 patients and embolisation of an arteriobiliary fistula in 1 patient. RESULTS: Biliary: We carried out external-internal drainage and balloon dilatation of stenoses in 12 cases. The external-internal drainage catheter was removed after 6-8 weeks in 7 patients, with the remaining 5 patients with persisting stenosis assigned for retransplantation. We failed to cross anastomotic occlusions in 2 patients before completing the procedures using external drainage; both individuals subsequently underwent retransplantation. Vascular: We performed PTA/stenting of HA stenoses/occlusions in 4 out of 5 patients. After the procedure, all 4 patients showed liver function normalisation. All 3 cases of embolisation were technically and clinically successful. Both IVC and PV stenoses treated with dilatation/stenting were also successful. CONCLUSIONS: Percutaneous techniques used to treat biliary and vascular complications after liver transplantation in paediatric patients are safe and efficient.

Uterus transplant graft's arterial atherosclerotic remodeling veracity.

BACKGROUND: Uterus transplantation is a complex, multi-step experimental procedure used for the treatment of uterus absence or uterus anomaly that prevents embryo implantation or pregnancy completion. METHOD: To date, only 51 uterus transplants worldwide had been performed. When simplified, it is vascularized composite allograft transplantation. While it is still an experimental procedure with encouraging results for the future, there are still many issues that have to be clarified. The most serious complications of uterus transplantation are graft rejection or grafts vascular failure. RESULTS: So far, no reference to the atherosclerotic arterial infiltration of the uterus arteries was suggested and studied as one of the main causes of graft's failure. CONCLUSION: In this review we summarized current knowledge and possible role of uterus arterial damage, including atherosclerotic changes on the graft's survival.

Large Hepatic Artery Pseudoaneurysm Resection After Orthotopic Liver Transplantation.

BACKGROUND Hepatic artery (HA) pseudoaneurysm (PSA) after liver transplantation (OLTx) is rare but often fatal complication requiring quick repair. Its prevalence in patients after OLTx is around 0.94%. CASE REPORT A 41-year-old female patient underwent a full-graft orthotopic liver transplantation (OLTx) for alcoholic liver cirrhosis in 2017. During regular postoperative Doppler ultrasonography (DU) check-ups, a large 3-cm pseudoaneurysm (PSA) was detected on the hepatic artery. The patient underwent a computed angiography (CTA) to verify the PSA anatomical localization and relationship with the transplanted liver graft. Selective celiac arteriography showed HA PSA and 90% stenosis of the hepatic artery after PSA. The stent graft placement was unsuccessful as the guiding wire was unable to pass through the post-PSA HA stenosis. The patient was scheduled for an open repair under general anesthesia. Through a right subcostal incision, the HA PSA was resected and the HA was mobilized and re-anastomosed using an end-to-end technique. Three months after the procedure, the patient has a good liver graft perfusion through the HA with no sign of PSA reoccurrence or stenosis. CONCLUSIONS Early detection of the HA PSA after OLTx is a life-threatening complication requiring prompt treatment. If endovascular treatment options fail, open surgical repair, despite its challenges, is the only possible treatment option.

The development of a silicone vaginal ring with a prostaglandin analogue for potential use in the treatment of canine reproductive disorders.

In veterinary medicine, vaginal rings (VRs) are rarely used. However, there are diseases of female dogs' reproductive system which represent a suitable possibility for their usage. An example of such a disease is canine pyometra which can be treated by lipophilic prostaglandin drugs, unfortunately with harmful side effects after systemic administration. The aim of the study was to prove that the matrix VR based on silicone and channel-forming substance can be successfully used as a carrier for a three-day delivery of prostaglandin E2 (PGE2). Based on an in-vitro release study, an optimum channel-forming substance and its concentration were selected. The results were implemented during the construction of VR from the medical grade silicone DDU-4840 with PGE2 (5 mg). Glucose anhydrous in the 30% concentration was chosen as the most functional channel-forming substance due to synergism of osmotic activity and solubility. The DDU-VR containing PGE2 and 30% of glucose anhydrous exhibited excellent mechanical characteristics and ensured 29% drug release through water-filled channels in first-order kinetic manner. This is eight times higher than a sample without glucose where molecular diffusion through the silicone matrix was dominating the release mechanism. Moreover, drug-free VRs were tested for mechanical resistance and the design of removal thread.

Spontaneous Isolated Common Iliac Artery Dissection Treated with Self-Expandable Stent in a 38-year-old Patient: A Case Report.

INTRODUCTION: Isolated iliac artery dissection (ISIAD) without the involvement of the aorta is a rare medical condition. REPORT: A case of a 38-year-old man with sudden onset of rest pain and paraesthesia on the right lower limb (RLL) is presented. Upon admission, the RLL was pulseless, with mild paraesthesia in the foot. The patient underwent computed tomography angiography, which revealed isolated common iliac artery (CIA) dissection followed by endovascular treatment (stenting) of the CIA dissection, with an instant therapeutic effect. Hospital stay was uneventful. The patient was discharged on the third post-procedural day. DISCUSSION: Endovascular treatment of ISIAD is a viable treatment modality, with low periprocedural complications, mortality, and morbidity. Owing to its mini-invasiveness, it is a viable treatment modality.

Acute appendicitis in a patient after a uterus transplant: A case report.

BACKGROUND: Acute appendicitis in a solid organ transplant recipient is a rare occurrence, and experience remains limited. Appendicitis in uterine transplant recipients has never been reported. Immunocompromised patients with acute abdomen often present late and with attenuated symptoms. The differential diagnosis in a transplanted patient is broad and challenging due to possible existing complications associated with the graft, effects of immunosuppression, and altered anatomical relations. CASE SUMMARY: A 26-year-old woman suffering from absolute uterine factor infertility received a uterus transplant. In the post-transplant period, she suffered from leukopenia and recurrent acute cellular rejection. Her compliance was suboptimal. She travelled to an exotic destination despite the physician's recommendation not to do so. Following her vacation, she presented with abdominal discomfort, nausea and diarrhoea. There was no sign of acute abdomen; the abdominal ultrasound was negative on day 0. Clostridium difficile colitis was verified and treated with perorally administered vancomycin. On day 4, the discomfort changed to pain; the ultrasound scan revealed a finding suggestive of appendicitis. Surgical exploration revealed perforated appendicitis, and appendectomy was performed. From a surgical point of view, the patient's follow-up was uneventful. The patient underwent a successful embryo transfer 6 months after the appendectomy. The patient gave birth to a healthy boy at the 35th week of gestation. CONCLUSION: A high index of suspicion of an atypical course and symptomatology of acute abdomen should be maintained in immunosuppressed patients.

Familial Adenomatous Polyposis and Desmoid Tumor Treated with Multivisceral Transplantation and Kidney Autotransplantation: Case Report and Literature Review.

INTRODUCTION: Desmoid tumours (DT) are commonly associated with Gardener's syndrome. Their surgical resection may be complicated by their close proximity to major vessels, multiple organ involvement, and frequent local recurrence. Multivisceral transplantation (MVTx) is an alternative treatment for patients with intestinal and liver failure. In patients with DT closely associated with renal structures but without end-stage kidney disease, concomitant excision of the patient's own kidney, ex vivo tumour resection with nephron-sparing surgery, or autotransplantation has been proposed. CASE PRESENTATION: A 36-year-old Caucasian female weighing 60 kg with Gardener's syndrome with a history of abdominal surgery was presented to our department with progressive abdominal distention associated with paroxysmal pain. With the use of CT, the patient was diagnosed with a mass arising from the mesenterial region. The patient had normal kidney function and nonalcoholic steatohepatitis. The patient was indicated for MVTx. MANAGEMENT AND OUTCOME: After 16 months on the waiting list, the patient received a multivisceral graft from a deceased donor. Following the restoration of graft vascular flow, the patient's right kidney was removed and the DT dissected ex vivo before autotransplantation into the right pelvic fossa. The patient received immunosuppressive, antithrombotic, and antibiotic treatment. There was no acute rejection, though the patient experienced pulmonary infection, dysphagia, and oesophageal reflux with fungal infection. The patient had required temporary dialysis for acute renal failure for 75 days. One year after the surgery, nausea and violent vomiting caused delayed gastric emptying caused by spastic pylorus. Clinical improvement was achieved using gastric peroral endoscopic myotomy (G-POEM). CONCLUSION: MVTx with kidney autotransplantation is a feasible treatment option in patients with familiar adenomatous polyposis complicated by an abdominal DT. Precise tumour dissection with nephron-sparing surgery was carried ex vivo. G-POEM was used to relieve MVTx-related gastroparesis. The patient had no disease reoccurrence after one-year follow-up.

Simultaneous living donor orthotopic renal transplantation and bilateral nephrectomy for recurrent renal cell carcinoma and renal failure: case report and review of literature.

BACKGROUND: We report the case of a 43-year-old female patient with systemic lupus erythematosus, class III lupus nephritis, with predialysis creatinine levels around 350 µmol/L (3.95 mg/dL) after partial resection of the left kidney with histologically verified papillary carcinoma in 2010. Preoperative computed tomography of the abdomen revealed a small 8 mm tumor in the left upper kidney pole. The patient was indicated for simultaneous bilateral nephrectomy and orthotopic renal transplantation with the aim to minimize invasiveness of the procedure as well as for curable tumor removal. METHOD: The procedure was performed under the full anesthesia trough upper middle laparotomy. As the first step, bilateral transperitoneal nephrectomy was performed. The live donor surgery started in a parallel theater to shorten the cold ischemic time of the graft. The renal graft had singe vessels and ureter; it was placed into the recipient's right orthotopic position. End-to-end anastomosis of the right renal vein and artery anastomosis were performed; ureter was anastomosed end-to-end using recipient's ureter. RESULTS: The postoperative period was uneventful with repeatedly excellent ultrasonography check-up of the graft's perfusion. The patient was discharged after 13 days with a good renal function of the graft (urea: 15 mmol/L, creatinine 160 µmol/L [1.80 mg/dL]). CONCLUSION: Orthotopic renal transplantation is a technically challenging but valid alternative for patients who are unsuitable candidates for heterotopic renal transplantation or in cases where there is a clear benefit of orthotopic renal transplantation.

Structural changes arising from different thawing protocols on cryopreserved human allograft's aortic valve leaflets.

BACKGROUND: The aim of our experimental work was to assess the impact and morphological changes that arise during different thawing protocols on human aortic valve (AV) leaflets resected from cryopreserved aortic root allografts (CARAs). OBJECTIVES: Two thawing protocols were tested: 1. CARAs were thawed at a room temperature (23°C); 2. CARAs were placed directly into a water bath at a temperature of 37°C. After all the samples were thawed, non-coronary AV leaflets were sampled from each specimen and fixed in a 4% formaldehyde solution before they were sent for morphological analysis. MATERIAL AND METHODS: All the samples were washed in distilled water for 5 min and dehydrated in a graded ethanol series (70%, 85%, 95%, and 100%) for 5 min at each level. The tissue samples were then immersed in 100% hexamethyldisilazane (HMDS) for 10 min, and then air-dried in an exhaust hood at room temperature. Processed samples were mounted on stainless steel stubs and coated with gold. Histological analysis was performed with the use of an electron microscope on a scanning mode operating at 25 kV - BS 301. RESULTS: Thawing protocol 1 (room temperature at 23°C): 6 (100%) samples showed loss of the endothelial covering of the basal membrane with no damage to the basal lamina. Thawing protocol 2 (water bath at 37°C): 5 (83%) samples showed loss of the endothelial covering of the basal membrane with no damage to the basal lamina. One (17%) sample showed loss of the endothelial covering the basal membrane with significant damage to the basal membrane. CONCLUSIONS: Based on our experimental work, we can clearly conclude that cryopreserved AV leaflet allografts show identical structural changes at different rates of thawing.

Fibrin sealants in cardiac surgery: The last five years of their development and application.

This review article describes the use of fibrin glue or fibrin sealants and their development over the past 5 years, with a focus on cardiac surgery. The roles of various types of sealants that are available in hemostasis control are reviewed briefly, together with the various potential risks and side effects of their use. The results of experimental work reported during the last 5 years, clinical data from the same period and the safety aspects of fibrin-based glues and sealants are summarized, showing many advantages of their clinical application over the use of synthetic glues or sealants that may be stronger in some cases, but less safe. It can be concluded that the widespread use of fibrin sealants is fully justified, as it benefits the patient as well as the surgeon through the improved control of hemostasis without increasing any adverse effects or complications during surgical procedures.

Role of Dipyrone in the High On-Treatment Platelet Reactivity amongst Acetylsalicylic Acid-Treated Patients Undergoing Peripheral Artery Revascularisation.

OBJECTIVE: To evaluate the effects of dipyrone on sensitivity to aspirin (acetylsalicylic acid [ASA]) in patients who underwent peripheral artery vascular reconstruction. SUBJECTS AND METHODS: Impedance aggregometry and light transmission aggregometry were used to determine the effects of dipyrone on ASA treatment in 21 patients. Blood samples were drawn in a 7-day period after the surgery. The cut-off value for high on-treatment platelet reactivity (HTPR) was set at < 65% of aggregation inhibition for impedance aggregometry. For light transmission aggregometry the cut-off value for arachidonic acid-induced aggregation was set at > 20% of aggregating platelets, and the cut-off value for epinephrine-induced aggregation was > 44% of aggregating platelets. The cut-off value for each method was derived from a large number of patients treated with a daily dose of 100 mg of ASA. RESULTS: We found HTPR in 14 (67%) of the 21 patients. None had primary resistance to ASA, i.e., after the addition of ASA in vitro all samples showed antiplatelet efficacy. Regression analysis showed a possible correlation between lower efficacy of ASA treatment and higher daily doses of dipyrone (p = 0.005 for impedance aggregometry, p = 0.04 for light transmission aggregometry), higher platelet count (p = 0.005 for impedance aggregometry), and shorter time from surgery (p = 0.03 for impedance aggregometry). CONCLUSION: HTPR occurs in 67% of ASA-treated patients after lower limb vascular surgery. The occurrence of HTPR correlates with the daily dose of dipyrone. Therefore, dipyrone should not be used as a postoperative analgesic in ASA-treated patients after peripheral artery revascularisation due to its influence on the effectiveness of ASA.

A comparison of quality parameters of fresh feline ejaculates collected by three different collection techniques.

The aim of our study was to compare the quality parameters of fresh feline ejaculates collected by three different techniques-urethral catheterization after medetomidine administration (CT), electroejaculation (EE) and epididymal slicing after orchiectomy (EP). A total of 34 adult male cats (Felis catus) were included in the study. In all male cats, the sperm collection was performed under general anaesthesia by three collection methods in the following order: urethral catheterization, electroejaculation and epididymal slicing. The sperm parameters evaluated were as follows: volume, motility, viability, sperm concentration, total sperm count and morphological examination. The highest quality semen parameters were achieved using EE. The comparison of results of the evaluated sperm quality parameters from EE and EP showed significant differences only in one case-the percentage of head abnormalities and lower percentage of head abnormalities were achieved using EE compared to EP: 8.5% (3.0%-21.0%) versus 10.0% (4.0%-22.0%). Semen collected by CT rendered the lowest quality samples when compared to sperm samples collected by EE and EP, especially with respect to the motility and total sperm count which were significantly lower (p < 0.001). Our study showed that sperm samples collected by EE and EP result in better quality of feline ejaculates compared to collection by CT from sperm samples collected from the same male cats. These results demonstrate the necessity of further research of urethral catheterization as a novel technique of semen collection in male cats.