The Effects of Rapamycin on the Intestinal Graft in a Rat Model of Cold Ischemia Perfusion and Preservation.

Attenuating the rheological and structural consequences of intestinal ischemia-reperfusion-injury (IRI) is important in transplant proceedings. Preconditioning is an often-proposed remedy. This technique uses physical or pharmacological methods to manipulate key ischemia pathways, such as oxidation, inflammation, and autophagy, prior to ischemia. This study determined the time-dependent effects of Rapamycin preconditioning on small-bowel grafts undergoing cold ischemia perfusion and preservation. Our main parameters were mucosa and cell injury and autophagy. A total of 30 male Wistar rats were divided into 5 groups: sham, preservation-control, and 3 treated groups (Rapamycin administered either 0, 30, or 60 min prior to perfusion). After perfusion, the intestines were placed in chilled IGL-1 solution for 12 h. Thereafter, they were reperfused. Histology and bioanalysis (LDH and lactate) were used to ascertain intestinal injury while immunohistochemistry was used for measuring changes in autophagy markers (Beclin-1, LC3B, and p62 proteins). The results show no significant difference amongst the groups after vascular perfusion. However, intestinal injury findings and autophagy changes demonstrate that administering Rapamycin 30 min or 60 min prior was protective against adverse cold ischemia and reperfusion of the intestinal graft. These findings show that Rapamycin is protective against cold ischemia of the small intestine, especially when administered 30 min before the onset.

The Effect of Trimetazidine on Diathermy-related Thermic Injury of the Rat Liver.

BACKGROUND/AIM: Owing to new oncotherapy modalities, the importance of an R0 resection decreased in the last decade; however, liver metastasis of colorectal cancer significantly decreases survival. Furthermore, to prevent cardiovascular disease, more and more patients are treated with anti-ischemic drugs, which may influence oncologic treatments in such patients. This study aimed to examine the effect of Trimetazidine on liver surface injury after spray diathermy. MATERIALS AND METHODS: We performed standard liver resections with resection-margin spray coagulation in 36 rats on both liver lobes. In all procedures, a Pringle maneuver was performed on the right lobe, while on the left lobe, no vessel occlusion was applied. Half of the animals were on Trimetazidine therapy. In 12 animals, histologic samples were taken immediately after operation, while 12 animals were terminated 1 week later, and the remaining 12 animals 3 weeks later. After standard HE staining, histologic analysis was performed. RESULTS: When diathermy was used, a coagulation zone appeared. Destruction was slightly wider in case of Trimetazidine therapy (745.75 vs. 680.04 µm). In cases of 1-week-surviving animals, a necrotic zone was observed under the coagulated tissue, and a fibrotic zone appeared after 3 weeks. In TMZ medicated animals, the destruction zone was significantly thinner (645.08 vs. 893.76 µm; p<0.001) and the necrosis zone showed the same difference (2,430.05 vs. 3,238.45 µm; p<0.001). CONCLUSION: Administration of Trimetazidine can reduce the extent of thermic necrosis. Furthermore, a great effort should be applied to achieve R0 resection in patients on anti-ischemic therapy.

Subnormothermic isolated organ perfusion with Nicorandil increased cold ischemic tolerance of liver in experimental model.

BACKGROUND: The cold ischemia -reperfusion injury may lead to microcirculatory disturbances, hepatocellular swelling, inflammation, and organ dysfunction. Nicorandil is an anti-ischemic, ATP-sensitive potassium (KATP) channel opener drug and has proved its effectiveness against hepatic Ischemia/Reperfusion (I/R) injury. OBJECTIVE: This study aimed to investigate the effect of Nicorandil on mitochondrial apoptosis, oxidative stress, inflammation, histopathological changes, and cold ischemic tolerance of the liver in an ex vivo experimental isolated-organ-perfusion model. METHODS: We used an ex vivo isolated rat liver perfusion system for this study. The grafts were retrieved from male Wistar rats (n = 5 in each), preserved in cold storage (CS) for 2 or 4 hours (group 1, 2), or perfused for 2 or 4 hours (group 3, 4) immediately after removal with Krebs Henseleit Buffer (KHB) solution or Nicorandil containing KHB solution under subnormothermic (22-25°C) conditions (group 5, 6). After 15 minutes incubation at room temperature, the livers were reperfused with acellular, oxygenated solution under normothermic condition for 60 minutes. RESULTS: In the Nicorandil perfused groups, significantly decreased liver enzymes, GLDH, TNF-alpha, and IL-1ß were measured from the perfusate. Antioxidant enzymactivity was higher in the perfused groups. Histopathological examination showed ameliorated tissue deterioration, preserved parenchymal structure, decreased apoptosis, and increased Bcl-2 activity in the Nicorandil perfused groups. CONCLUSIONS: Perfusion with Nicorandil containing KHB solution may increase cold ischemic tolerance of the liver via mitochondrial protection which can be a potential therapeutic target to improve graft survival during transplantation.

Characterizing Autophagy in the Cold Ischemic Injury of Small Bowel Grafts: Evidence from Rat Jejunum.

Cold ischemic injury to the intestine during preservation remains an unresolved issue in transplantation medicine. Autophagy, a cytoplasmic protein degradation pathway, is essential for metabolic adaptation to starvation, hypoxia, and ischemia. It has been implicated in the cold ischemia (CI) of other transplantable organs. This study determines the changes in intestinal autophagy evoked by cold storage and explores the effects of autophagy on ischemic grafts. Cold preservation was simulated by placing the small intestines of Wistar rats in an IGL-1 (Institute George Lopez) solution at 4 °C for varying periods (3, 6, 9, and 12 h). The extent of graft preservation injury (mucosal and cellular injury) and changes in autophagy were measured after each CI time. Subsequently, we determined the differences in apoptosis and preservation injury after activating autophagy with rapamycin or inhibiting it with 3-methyladenine. The results revealed that ischemic injury and autophagy were induced by cold storage. Autophagy peaked at 3 h and subsequently declined. After 12 h of storage, autophagic expression was reduced significantly. Additionally, enhanced intestinal autophagy by rapamycin was associated with less tissue, cellular, and apoptotic damage during and after the 12-h long preservation. After reperfusion, grafts with enhanced autophagy still presented with less injury. Inhibiting autophagy exhibited the opposite trend. These findings demonstrate intestinal autophagy changes in cold preservation. Furthermore, enhanced autophagy was protective against cold ischemia-reperfusion damage of the small bowels.

Effect of Pioglitazone on endoplasmic reticulum stress regarding in situ perfusion rat model.

BACKGROUND: Ischemia-reperfusion injury (IRI) can cause insufficient microcirculation of the transplanted organ and results in a diminished and inferior graft survival rate. OBJECTIVE: This study aimed to investigate the effect of different doses of an anti-diabetic drug, Pioglitazone (Pio), on endoplasmic reticulum stress and histopathological changes, using an in situ perfusion rat model. METHODS: Sixty male Wistar rats were used and were divided into six groups, consisting of the control group, vehicle-treated group and four Pio-treated groups (10, 20, 30 and 40 mg/kg Pio was administered). The rats were perfused through vena cava and an outflow on the abdominal aorta occurred. Following the experiment, kidneys and livers were collected. The level of the endoplasmic reticulum stress markers (XBP1 and Caspase 12) was analyzed using Western blot and histopathological changes were evaluated. RESULTS: Histopathological findings were correlated with the Western blot results and depict a protective effect corresponding to the elevated dosage of Pioglitazone regarding in situ perfusion rat model. CONCLUSIONS: In our study, Pioglitazone can reduce the endoplasmic reticulum stress, and the most effective dosage proved to be the 40 mg/kg Pio referencing the kidney and liver samples.

Short- and Long-term Histological Changes in Liver Parenchyma After Different Resection Methods and Their Potential Role in Treatment of Colorectal Liver Metastasis.

BACKGROUND/AIM: Optimal surgical margins, parenchymal-sparing technique and the effect of the surgical devices on the liver resection surface are currently hot topics. The aim of this study was to set up a surviving animal model to detect histological changes on the resection surface induced by the resection method and the thermal effect of monopolar electrocautery in 'spray mode'. MATERIALS AND METHODS: Eighteen male Wistar rats were used; all rats were subjected to standardized liver resection and resection surface coagulation. Resection surface samples were collected immediately after the operation from the first group, and at 1 week and 3 weeks after the operation from the second and third groups, respectively. The samples were histologically investigated. RESULTS: Spray diathermy was shown to cause parenchymaI destruction of varying depth on the resection surface due to immediate coagulation and consequent necrosis. CONCLUSION: Spray diathermy on the resection surface can also destroy the area that contains possible tumor cells after R1 resection and increases the tumor clearance without worse survival outcomes.

The effect of trimetazidine in reducing the ischemia-reperfusion injury in rat epigastric skin flaps.

BACKGROUND: Ischemia-reperfusion injury may lead to insufficient microcirculation and results in partial flap loss during the free flap surgeries. OBJECTIVE: This study aimed to investigate the effect of trimetazidine (TMZ) on oxidative stress, inflammation and histopathological changes, using the epigastric skin flap model in rats. METHODS: 40 male Wistar rats were used, that were divided into four groups. Control group, non-treated ischemic (I/R)-group and two trimetazidine treated groups (preischemically, postischemically) were established. To create ischemia in the skin flap, the superficial epigastric vessels were clamped for six hours, followed by twenty-four hours of reperfusion. Blood samples and biopsies from skin flaps were collected at the end of the reperfusion period. The inflammatory response, the degree of oxidative stress (by measuring the plasma level of malondialdehyde (MDA), reduced glutathione (GSH); sulfhydryl (-SH) groups) and histopathological changes were evaluated. RESULTS: Inflammatory response, and oxidative stress were significantly attenuated in the trimetazidine treated groups, compared to the non-treated ischemic group. Histopathological findings were also correlated with the biochemical results. CONCLUSION: In our study trimetazidine could reduce the ischaemia-reperfusion injury, even after an unexpected ischemic period, so it is a promising drug during free tissue transfer, replantation or during revascularization procedures in the future.

Pneumoperitoneum induced ischemia-reperfusion injury of the peritoneum - Preconditioning may reduce the negative side-effects caused by carbon-dioxide pneumoperitoneum - Pilot study.

INTRODUCTION: Laparoscopy is more beneficial than the conventional open technique, however the pneumoperitoneum created may have an ischemic side effect. OBJECTIVE: Our aim was to evaluate the protective effects of preconditioning during laparoscopic cholecystectomies (LC). METHODS: 30 patients were randomized into 2 groups: I. PreC (preconditioning: 5 min. inflation, 5 min. deflation, followed by conventional LC), II: LC (conventional LC). Blood samples were taken before hospitalization (C = control), before surgery, after anaesthesia (B.S.), after surgery (A.S.) and 24 hours after the procedure (24 h). Measured parameters were: malondialdehyde (MDA), reduced glutathione (GSH), sulfhydril groups (-SH), superoxide-dismutase (SOD), catalase (CAT), myeloperoxidase (MPO), length of hospitalization and pain (VAS = visual analogue scale). RESULTS: Compared to the BS levels, no significant changes were detected in SOD's activity and MDA levels. GSH concentrations were significantly increased in the PreC group after operation. SH-, MPO, CAT and liver function enzymes were not significantly different. Hospitalization was shorter in the PreC group. Based on the VAS score patients had less pain in the PreC group. CONCLUSION: Significant differences concerning PreC group were found in GSH values. In the PreC group pain decreased by 2-2.5 units following the procedure, 24 h after surgery, and hospitalisation was also significantly shorter. In our pilot study the potential protective effect of preconditioning could be defined.

Toward harmonization of interpretive commenting of common laboratory tests.

Interpretive commenting (IC) is an integral part of postanalytical activities of laboratories when the clinical interpretation of laboratory results in the context of the clinical situation of a patient is provided. Harmonizing practices in IC can be an approach to ensure high-quality comments, which if followed by adequate clinical actions has a great potential in improving patient outcomes. This paper reviews basic work prior to harmonization of IC of common laboratory test results. Practices in IC are considerably diverse both within and between countries. The quality of comments is diverse and often clinically misleading in studies that characterize and estimate error prevalence in IC. Systems that can initiate, monitor, and maintain harmonization in IC are in an evolving state. Despite international initiatives, harmonized, implementable performance indicators and goals in IC are not yet available. External quality assurance (EQA) schemes are accessible mainly in English-speaking countries. A proposal for the standard structure of EQA schemes for interpretive comments in clinical chemistry and best practice recommendations for IC are available. Few studies that demonstrate evidence on the clinical utility of IC are available in the literature. To set a strategy on further steps toward harmonization in IC, well-controlled clinical studies need to be conducted, in collaboration with laboratories and their users on the clinical usefulness of IC. Until enough evidence on the value of IC in patient outcomes accumulates, standards of qualification and training for performing IC and more EQA schemes in native languages of the users are required to improve the quality of IC.

Pentoxifylline attenuates the local and systemic inflammatory response after infrarenal abdominal aortic ischemia-reperfusion.

AIMS: We studied the new anti-inflammatory effects of non-specific phosphodiesterase (PDE) inhibitor pentoxifylline (PTX) on ischaemia-reperfusion injury and postconditioning of the lower extremities. We aimed to examine the oxidative stress parameters (OSP), the inflammatory response and the changes in structure of skeletal muscle after revascularization surgery. METHODS: 50 Wistar rats in five groups underwent a 60 min infrarenal aortic cross clamping. After the ischaemia in IR+PC group ischemic postconditioning was performed, intermittent 15 seconds reperfusion, 15 seconds ischaemic periods were applied four times. The ischemic phase was followed by a 120 min of reperfusion. In IR+PTX group the animals were treated with PTX. In IR+PC+PTX group both ischemic postconditioning and PTX treatment were performed. Blood samples and biopsy from quadriceps muscle were collected. Plasma malondialdehyde, reduced glutathione, -SH-groups, TNF-alpha, IL-6 concentrations and superoxide dismutase enzyme activity were measured. RESULTS: The levels of OSP and the inflammatory proteins were significantly higher in the IR group. PTX treatment and PC could significantly decrease the levels of OSP and inflammatory proteins. When the animals were co-treated with PTX and PC the results were even better. CONCLUSIONS: Inhibition of PDE by PTX could markedly decrease the inflammatory response and moderate the ischaemia-reperfusion damages after lower limb ischemia and reperfusion. Administration of PTX could potentiate the beneficial effects of PC.

Morphological and Histological Effects of Radiofrequency and Laser (KTP and Nd:YAG) Treatment of the Inferior Turbinates in Animals.

The aim of this study was to evaluate the short and medium-term effects of radiofrequency (RF) and potassium titanyl phosphate (KTP) and neodymium-yttrium-aluminum garnet (Nd:YAG) laser treatment on the inferior turbinate mucosa in a porcine model. Following randomization, the inferior turbinates were treated either with RF submucosally or with the KTP or the Nd:YAG laser on the surface under videoendoscopic control. Tissue samples were taken at the end of postoperative weeks 1 and 6, and were evaluated macroscopically and histopathologically. Scanning electron microscopy was implemented to demonstrate the morphological changes in the respiratory epithelium. Six weeks following the RF procedure, the mucosa was intact in all cases, and the volume of the inferior turbinates was reduced in the majority of the cases. Although a volume reduction occurred in both laser groups, more complications associated with the healing procedure were noted. With hematoxylin and eosin and periodic acid-Schiff staining, intact epithelium, and submucosal glands remained after the RF procedures at the end of postoperative week 6. Following the KTP-laser intervention, necrotizing sialometaplasia and cartilage destruction occurred, and squamous metaplasia was also apparent in the Nd:YAG group. In both laser groups, dilated glands with excess mucus were seen. The scanning electron microscopic findings demonstrated that cilia were present in all cases. In conclusion, the medium-term macroscopic results were similar in all 3 groups, but the postoperative complications were less following the RF procedure. RF procedure is minimally invasive due to the submucosal intervention that leads to a painless, function preserving recovery.

Sodium Pentosan Polysulfate Reduced Renal Ischemia-Reperfusion-Induced Oxidative Stress and Inflammatory Responses in an Experimental Animal Model.

Acute kidney injury (AKI) remains an independent risk factor for mortality and morbidity after vascular surgery (affecting the renal arteries) or aortic surgery (requiring suprarenal aortic clamping). These types of vascular surgery produce renal ischemia/reperfusion (I/R) injury, a common cause of AKI. The present studies aimed at monitoring the course of renal I/R injury at the cellular level and investigating the efficacy of long-term preoperative and single-shot intraoperative administration of sodium pentosan polysulfate (PPS) to protect renal tissue from acute I/R injury both in native and diabetic kidneys in rats. Western blot analyses of the proapoptotic (bax) and antiapoptotic (bcl-2) signaling pathways, as well as the extent of DNA damage (phospho-p53), were performed. Oxidative stress followed upon the termination of malondialdehyde, reduced glutathione, thiol group, and superoxide dismutase plasma levels. Inflammatory changes were measured by the determination of serum tumor necrosis factor-α and interleukin-1 levels. Morphological changes were detected by histological examinations. Our results showed that the long-term administration of PPS has an advantage in reducing I/R kidney injury in diabetic rats, while high-dose, single-shot parenteral administration of PPS prior to revascularization might be useful in nondiabetic rats.

Inhibition of Glutathione S-Transferase by Ethacrynic Acid Augments Ischemia-Reperfusion Damage and Apoptosis and Attenuates the Positive Effect of Ischemic Postconditioning in a Bilateral Acute Hindlimb Ischemia Rat Model.

AIMS: We studied the effects of the inhibition of the endogene antioxidant glutathione-S-transferase (GST) by ethacrynic acid (EA) on ischemia-reperfusion (IR) injury and postconditioning (PC) in the lower extremities. We aimed to examine the oxidative stress parameters (OSP), inflammatory response and activation of proapoptotic signaling proteins (PSP) after revascularization surgery. METHODS: Sixty Wistar rats were divided into 6 groups: control, IR, PC, EA-control, IR and administration of EA (IR/EA) and PC and administration of EA (PC/EA). The IR, PC, IR/EA and PC/EA groups underwent 60 min of infrarenal aortic cross-clamping. After that, PC was performed in the PC and PC/EA groups. In 3 of the groups, the animals were treated with EA (EA-control, IR/EA and PC/EA groups) as well. The ischemia was followed by 120 min of reperfusion. Blood samples and biopsy specimens were collected from the quadriceps muscle. Plasma malondialdehyde, reduced glutathione, thiol/sulfhydryl group levels, TNF-α and IL-6 concentrations and superoxide-dismutase enzyme activity were measured. RESULTS: The levels of the OSP and the inflammatory proteins were higher in the EA-administered groups. The ratio of phosphorylated PSP was higher in the EA-administered groups and the protective effect of PC did not develop. CONCLUSIONS: Inhibition of GST by EA augmented the IR damage. GST inhibition was associated with a different activation of the mitogen-activated protein kinases and the PSP, regulating these pathways in the process of apoptosis and PC.

Evaluation of efficacy and biocompatibility of a novel semisynthetic collagen matrix as a dural onlay graft in a large animal model.

BACKGROUND: Semisynthetic collagen matrices are promising duraplasty grafts with low risk of cerebrospinal fluid (CSF) fistulas, good tissue integration and minor foreign body reaction. The present study investigates the efficacy and biocompatibility of a novel semisynthetic bilayered collagen matrix (BCM, B. Braun Aesculap) as dural onlay graft for duraplasty. METHODS: Thirty-four pigs underwent osteoclastic trepanation, excision of the dura, and placement of a cortical defect, followed by duraplasty using BCM, Suturable DuraGen™ (Integra Neuroscience), or periosteum. CSF tightness and intraoperative handling of the grafts were evaluated. Pigs were sacrificed after 1 and 6 months for histological analysis. FINDINGS: BCM and DuraGen™ showed superior handling than periosteum with a trend for better adhesion to dura and CSF tightness for BCM. Periosteum, which was sutured unlike the synthetic grafts, had the highest intraoperative CSF tightness. Duraplasty time with periosteum was significantly higher (14.4 ± 2.7 min) compared with BCM (2.8 ± 0.8 min) or DuraGen™ (3.0 ± 0.5 min). Tissue integration by fibroblast infiltration was observed after 1 month for all devices. More adhesions between graft and cortex were observed with DuraGen™ compared with BCM and periosteum. No relevant adhesions between leptomeninges and BCM were observed and all devices showed comparable lymphocytic reaction of the brain. All devices were completely integrated after 6 months. BCM and DuraGen™ showed a trend for an enhanced lymphocytic reaction of the brain parenchyma compared with periosteum. Implant rejection was not observed. CONCLUSION: Semisythetic collagen matrices are an attractive alternative in duraplasty due to their easy handling, lower surgical time, and high biocompatibility.

Comparative immunohistochemical study of tissue integration of macroporous and laminar surgical meshes.

Intraperitoneal surgical mesh implantation is required for laparoscopic ventral hernia repair. Composite meshes are well known in animal models and human practice. The aim of our study is to compare the biological behaviour of two different textured silicone-covered polypropylene meshes. Transmural abdominal wall defect was created in 40 rabbits and treated as follows: In 20 animals a polypropylene mesh with a laminar silicone covering (LSPP) and in the rest a macroporous textured mesh knitted of silicone-impregnated polypropylene filaments (MSPP) was applied. One and three weeks after implantation we evaluated the intraperitoneal adhesion formation of the mesh macroscopically, histologically and immunohistochemically to detect the reactive cells, especially inflammatory, endothelial and mesothelial cells, as well as their proliferative activity, and with Scanning Electron microscopy to visualize the surface of the meshes. The adhesion formation caused by the composites showed no statistical difference after one week although in the three weeks old samples the LSPP adhesion was significantly weaker than that of MSPP. As complications, serome formation in both groups, fistulas, abscesses, and sc. haematoma in the LSPP group were found. Only in MSPP containing tissues was the decrease of Ki-67 positive proliferating cells significant. A significant increase in VEGF expressing cells was observed only in MSPP containing three week old samples, suggesting better regulation of vascular growth in tissues surrounding the implants. In one week old specimens we observed an irregular proliferation of cytokeratin containing mesothelial cells in both group. The intraperitoneal surface of MSPP mesh was covered with neoperitoneum, while it was not regularly seen on LSPP mesh after three week.

[Tissue integration of various silicone-coated polypropylene surgical mesh]. / A különbözo szilikonbevonatú polipropilén hálók szöveti integrációja.

INTRODUCTION/AIM: Laparoscopic ventral hernia repair requires a surgical mesh implanted in intraperitoneal position. The combined, double layer meshes are promising in animal models as well as in human practice. The aim of this study was to compare the biological behaviour of two different textured silicone covered polypropylene mesh. MATERIALS AND METHODS: 3 × 4 cm big full thickness defect of the abdominal wall was created in New Zealand White rabbits. The defect was covered in 20 animals with a polypropylene mesh with laminar silicone layer on the visceral surface (LSPP), while the remaining 20 cases the defects were covered with a macroporous textured silicone impregnated polypropylene mesh (MSPP). Intraperitoneal adhesion formation and tissue ingrowth in the meshes were investigated. Immunohistochemistry was used to detect proliferation activity (Ki-67), neovascularization (VEGF), and to visualize mesothelial layer (CK) over the mesh. Scanning electron microscopy was used to investigate the visceral surface of the meshes. RESULTS: While intraperitoneal adhesion formation showed no difference after 1 week, LSPP mesh induced significantly less adhesions after 21 days. The Ki-67 positivity was significantly lower and the number of the VEGF positive cells increased with time in the MSPP group, this was missing in the LSPP group. The thin neoperitoneum layer was detected over MSPP mesh only with CK antibody. CONCLUSION: The material and texture of the mesh are responsible for tissular incorporation which is in accordance with the generated foreign body reaction.

Efficacy of different hemostatic devices for severe liver bleeding: a randomized controlled animal study.

BACKGROUND: Correct hemostasis in liver surgery is hard to achieve because of the oozing bleeding. The aim of this study was to compare the potential benefits of a new compress to the 2 commercial hemostatic compresses. METHODS: Collagen- and cellulose-based hemostatics were investigated. A standardized resection was treated by applying different hemostatics in a randomized order, and bleeding times were measured. Macroscopic evaluation of the liver and tissue sampling for histological investigations were carried out after 21 days. RESULTS: The bleeding times of bovine collagen (BoCo), protein-coated equine collagen (PECo), and oxidized cellulose (OxCe) were 140 ± 88, 243 ± 140 (P = .005 vs BoCo), and 352 ± 70 s (P < .001 vs BoCo), respectively. Microscopic evaluation of the PECo presented fibrosis and significant inflammation in the implantation zone, whereas BoCo and OxCe caused only fibrosis in the wound area. CONCLUSION: BoCo showed significantly better hemostatic effect than PECo and OxCe.

[A new method for prosthetisation of vascular patients with lower limb amputation: initial experiences with osseointegration technique]. / Alsóvégtag-amputált érbetegek új protetizációs lehetôsége: kezdeti tapasztalataink az osseointegrációs technikával.

INTRODUCTION/AIMS: Prostheses use for lower limb amputees is difficult, while the socket is hard, the prosthesis is heavy. Drawbacks of conventional prosthesis are mainly associated with the socket, therefore osseointegration technique is a promising solution, since it doesn't require a socket. Our aim was to introduce this technique in Hungary and extend indication for vascular patients. METHODS: The method includes two operative and one rehabilitation phases: during first operation a titanium screw is fixed into the femoral bone marrow cavity, this connects to an abutment, which also penetrates the skin, making a direct connection between the femur and the prosthesis during the second intervention. During rehabilitation the patient makes loading exercises and learns to walk with new prosthesis. RESULTS: This method was launched in Hungary in 2005. Two female amputees were operated on initially, their second surgery was performed in 2006 (when titanium screw was applied in the male patients, as well). Incorporation of titanium screw was exquisite, and rehabilitation was successful. One of our male patients died eight months after his first operation due to myocardial infarction. CONCLUSION: Based on our experiences, the osseointegration technique facilitates rehabilitation of vascular patients for prostheses use. Adequate follow-up and stable vascular diseases are not contraindications, although further clinical trials are needed to determine its indication.

[Transvaginal cholecystectomy in animal model: first series in Hungary]. / Transvaginalis cholecystectomia állatmodellen--kezdeti tapasztalataink.

INTRODUCTION: The Natural Orifice Transluminal Endoscopic Surgery (NOTES) is the newest trend in minimally invasive surgery. Based on clinical experiences, transvaginal cholecystectomy causes less pain and operative stress, requires shorter hospitalization and allows patients to return quicker to normal activity. MATERIALS AND METHODS: A transvaginal cholecystectomy was carried out using hybrid technique in animal model first time in Hungary. A 5 mm umbilical trocar was used for preparation of cystic artery and duct, clip application and gallbladder dissection. A transvaginally inserted 10 mm trocar was used for laparoscopic camera to follow the procedure. Gallbladder was fixed and secured with a special curved instrument inserted also transvaginally during the procedure. At the end of procedure the gallbladder was removed transvaginally. RESULTS: Six transvaginal cholecystectomies was performed on pigs. The mean time of operations was 78 min (40-145 minutes). During the operations and the follow up period (3 months) no complications and mortality was detected. CONCLUSIONS: According to our experiences both procedures can be safely carried out on animal model, but further refinement of devices is necessary.

[Biological behavior of polypropylene meshes suitable for intra-abdominal implantation in animal model]. / Intraabdominalis implantatióra alkalmas polypropylene hálók biológiai viselkedésének vizsgálata állatkísérletes modellben.

The expected incisional hernia rate is between 11-20% after laparotomy. Using mesh repair the results of the hernioplasty have recently improved. However the complication of mesh implants--especially in intraperitoneal position--can be life threatening. Additionally the appropriate mesh is expensive. We tried to create a mesh, which can be used intraperitoneally and generates adhesion in the abdominal wall, but keeps the intraabdominal organs adhesion free. Our experiments were divided into four groups. In the first we used different materials to cover the intraperitoneal side of polypropylene mesh. In the second phase three different pore-sized meshes were compared. In the third part the biological behavior of three different material-reduced meshes were investigated. Based on our previous results in the last session we used only silicone membrane protected material-reduced polypropylene meshes to cover the abdominal defects. Our experiments have shown that intraperitoneal implant with silicone-covered Vypro (Ethicon)/Premilene (B. Braun Medical) mesh significantly decreases the formations of adhesion.