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Background: Chronic pain is a debilitating condition that affects people all over the world. To effectively treat chronic pain patients, assignment to patient-centered functional restoration and psychological pain rehabilitation programs at an early stage is essential., Methods: This article describes the initial patient screening and evaluation process for an interdisciplinary chronic pain rehabilitation program and highlights the relevant points that should be covered in each section of the initial assessment., Results: A thorough, detailed history that includes an evaluation of the patient's pain, functional limitations, prior medications, prior procedures/interventions, substance abuse, and psychiatric disorders, as well as the patient's social, legal, and developmental histories, are key to the proper screening and appropriate treatment of patients with chronic pain., Conclusion: Thorough initial evaluation of patients is essential for proper enrollment in a chronic pain rehabilitation program. Such programs allow early treatment and reduce unnecessary health costs. Future prospective studies are needed to identify additional screening methods and triage tools to allow early admission of appropriate patients to these rehabilitation programs.

Background: Despite its small size, the coccyx has several important functions. Along with being the insertion site for multiple muscles, ligaments, and tendons, it also serves as one leg of the tripod-along with the ischial tuberosities-that provides weight-bearing support to a person in the seated position. The incidence of coccydynia (pain in the region of the coccyx) has not been reported, but factors associated with increased risk of developing coccydynia include obesity and female gender., Methods: This article provides an overview of the anatomy, physiology, and treatment of coccydynia., Results: Conservative treatment is successful in 90% of cases, and many cases resolve without medical treatment. Treatments for refractory cases include pelvic floor rehabilitation, manual manipulation and massage, transcutaneous electrical nerve stimulation, psychotherapy, steroid injections, nerve block, spinal cord stimulation, and surgical procedures., Conclusion: A multidisciplinary approach employing physical therapy, ergonomic adaptations, medications, injections, and, possibly, psychotherapy leads to the greatest chance of success in patients with refractory coccyx pain. Although new surgical techniques are emerging, more research is needed before their efficacy can be established.

Vertebral compression fractures can result from advanced osteoporosis, or less commonly from metastatic or traumatic insults to the vertebral column, and result in disabling pain and decreased functional capacity. Various vertebral augmentation options including kyphoplasty aim at preventing the sequelae of pain and immobility that can develop as the result of the vertebral fractures. The mechanism for pain relief following kyphoplasty is not entirely understood, and the restoration of a portion of the lost vertebral height is a subject of debate. We retrospectively reviewed radiographic imaging, pain relief, analgesic intake and functional outcomes in 67 consecutive patients who underwent single- or multilevel kyphoplasty with the primary goal of quantifying the restoration of lost vertebral height. We observed a mean of 45% of the lost vertebral height restored postprocedurally. Secondarily, kyphoplasty was associated with significant decreases in pain scores, daily morphine consumption and improvement in patient-reported functional measures., (© 2013 World Institute of Pain.)

Background: Lung protective ventilation may lead to hypoventilation with subsequent hypercapnic acidosis (HA). If HA cannot be tolerated or occurs despite increasing respiratory rate or buffering, extracorporeal CO2-removal using a percutaneous extracorporeal lung assist (pECLA) is an option. We hypothesised that compensation of HA using pECLA impairs regional perfusion. To test this hypothesis we determined organ blood flows in a lung-injury model with combined hypercapnic and metabolic acidosis., Methods: After induction of lung injury using hydrochloric acid (HCl) aspiration and metabolic acidosis by intravenous HCl infusion in nine pigs, an arterial-venous pECLA device was inserted. In randomised order, four treatments were tested: pECLA shunt (1) with and (2) without HA, and clamped pECLA shunt (3) with and (4) without HA. Regional blood flows were measured with the coloured microsphere technique., Results: HA resulted in higher perfusion in adrenal glands, spleen and parts of splanchnic area (P < 0.05) compared with normocapnia. During CO2-removal with pECLA, regional perfusion decreased to levels comparable with those without pECLA and normocapnia. Cardiac output (CO) increased during HA without a pECLA shunt and was highest during HA with a pECLA shunt compared with normocapnia. During CO2-removal with pECLA, this variable decreased but stayed higher than during normocapnia with clamped pECLA shunt (P < 0.05)., Conclusion: In our lung-injury model, HA was associated with increased systemic and regional blood flow in several organs. pECLA provides effective CO2 removal, requiring a higher CO for perfusion of the pECLA device without improvement of regional organ perfusion., (© 2013 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Others and we have shown in several studies that the natural tetrahydropyrimidine ectoine protects mammalian cells and tissues against various stress factors including ischemia/reperfusion injury, UV-irradiation, and inflammation. Since little is known about the molecular mechanism of this protective effect, which was ascribed exclusively to an extracellular action of this small water-soluble molecule, we asked whether and how a hydrophobic anchor modulates the inflammation protective properties of ectoine. We therefore investigated the influence of ectoine and of its semi-synthetic derivative lauryl-ectoine on inflammation in RAW 264.7 macrophages and primary cultured rat intestinal smooth muscle (RISM) cells. Both, ectoine and lauryl-ectoine considerably decreased lipopolysaccharide (LPS)-induced interleukin (IL)- 1, IL-6, tumor necrosis factor (TNF)- α, and cyclooxygenase (COX)-2 gene expression in macrophages as well as TNF-α- induced IL-1, IL-6 and COX-2 expression in RISM cells. This reduction of inflammatory agents was accompanied on the one hand by a significant decrease of nuclear translocation of nuclear factor (NF)-κB and on the other hand by a reduction of cellular ceramide content. Interestingly, lauryl- ectoine was much more active exerting its effect at about 10-fold lower concentrations than its natural counterpart. Note that ectoine was almost completely recovered in the medium whereas lauryl-ectoine was found to be cell-associated. Together our data indicate that a lipid anchor considerably improves a possible preventive and/or therapeutic implementation of ectoine in inflammatory processes.

We conducted a retrospective audit of six patients with various haematological malignancies (two acute lymphoblastic leukaemia, one acute myeloid leukaemia, and three non-Hodgkin lymphoma); these patients were eligible to receive rasburicase, being at high risk of development of tumour lysis syndrome (TLS). They received a fixed single low-dose regimen of rasburicase (7.5 mg) mainly due to financial restriction, as patients were not supported by the National Health Service and did not have health insurance. We compared uric acid, creatinine levels, and electrolytes (i.e. phosphate, potassium, and calcium) before and after rasburicase administration and also assessed the need for renal replacement therapy after treatment. All six patients had a significant reduction in uric acid levels on the first day, achieving a response rate of 100% (p = 0.008994); creatinine, phosphate, and potassium were reduced significantly as well, with the p values of 0.0439, 0.014326, and 0.002008, respectively; only one patient needed renal replacement therapy in the form of haemodialysis, due to concerns about hyperphosphataemia. Financial difficulties faced either because patients lacked insurance or because of the restricted National Health Service budget in Egypt have resulted in the unavailability of certain modalities of treatment in cancer care and the need to consider more economic yet efficient approaches. Our experience suggests that a single low-dose rasburicase injection (7.5 mg) is an efficient and cost-effective method to control hyperuricaemia in patients with a high risk of developing TLS when compared with the more expensive and extended standard regimen and doses recommended.

Liver fibrosis is defined as excessive extracellular matrix deposition and is based on complex interactions between matrix-producing hepatic stellate cells and an abundance of liver-resident and infiltrating cells. Investigation of these processes requires in vitro and in vivo experimental work in animals. However, the use of animals in translational research will be increasingly challenged, at least in countries of the European Union, because of the adoption of new animal welfare rules in 2013. These rules will create an urgent need for optimized standard operating procedures regarding animal experimentation and improved international communication in the liver fibrosis community. This review gives an update on current animal models, techniques and underlying pathomechanisms with the aim of fostering a critical discussion of the limitations and potential of up-to-date animal experimentation. We discuss potential complications in experimental liver fibrosis and provide examples of how the findings of studies in which these models are used can be translated to human disease and therapy. In this review, we want to motivate the international community to design more standardized animal models which might help to address the legally requested replacement, refinement and reduction of animals in fibrosis research.

Background: Postoperative peritoneal adhesion formation following abdominal surgery remains a relevant surgical problem. The application of soluble physico-chemical barriers like 4% icodextrin is one approach to protect the peritoneal surface from getting linked to adhesive scar. The aim of this study was to investigate the influence of 4% icodextrin on peritoneal tissue response both of visceral and parietal peritoneum, adhesion formation and wound healing., Methods: 40 rats were divided into two groups. After creation of an intraabdominal defect, either 4% icodextrin (Adept®) or sodium chloride was applied. Animals were sacrificed after 7 and 21 days. Adhesions were scored by an adhesion score. Furthermore, immunohistochemical investigations were conducted to determine the discrete influence of icodextrin on the parietal and visceral peritoneal tissue responses (CD68+ macrophages, CD3+ T-lymphocytes, vimentin for mesenchymal cells, HBME-1 for mesothelial cells, and as components of wound healing COX-2, C-myc, catenin)., Results: Postoperative peritoneal adhesions were predominantly present in the sodium chloride group as compared to the icodextrin group (14/19 (74%) vs. 9/19 (47%); p = 0.048). The adhesion score however did not reveal any significant differences, (p = 0.614). Furthermore, the expression of vimentin in both the parietal and visceral peritoneum after 21 days was significantly lower in the icodextrin group than in the sodium chloride group (p = 0.038 and p = 0.028, respectively). No significant differences were observed for macrophages, lymphocytes, reperitonealisation or the expression of COX-2, C-myc or Catenin., Conclusions: The intraperitoneal application of 4% icodextrin reduces adhesion formation in comparison to sodium chloride. 4% icodextrin solution reduces the inflammatory and mesenchymal infiltrate in the wounded area, thus improving the ratio of mesothel cells to mesenchymal infiltrate. As demonstrated, icodextrin is able to ameliorate the local tissue response. Further experimental studies would be done to elaborate the impact on the early response of the adaptive immune system, which may then trigger the subsequent wound healing and tissue repair.

Suitable and reproducible experimental models of translational research in reconstructive surgery that allow in-vivo investigation of diverse molecular and cellular mechanisms are still limited. To this end we created a novel murine model of acute hindlimb ischemia-reperfusion to mimic a microsurgical free flap procedure. Thirty-six C57BL6 mice (n = 6/group) were assigned to one control and five experimental groups (subject to 6, 12, 96, 120 hours and 14 days of reperfusion, respectively) following 4 hours of complete hindlimb ischemia. Ischemia and reperfusion were monitored using Laser-Doppler Flowmetry. Hindlimb tissue components (skin and muscle) were investigated using histopathology, quantitative immunohistochemistry and immunofluorescence. Despite massive initial tissue damage induced by ischemia-reperfusion injury, the structure of the skin component was restored after 96 hours. During the same time, muscle cells were replaced by young myotubes. In addition, initial neuromuscular dysfunction, edema and swelling resolved by day 4. After two weeks, no functional or neuromuscular deficits were detectable. Furthermore, upregulation of VEGF and tissue infiltration with CD34-positive stem cells led to new capillary formation, which peaked with significantly higher values after two weeks. These data indicate that our model is suitable to investigate cellular and molecular tissue alterations from ischemia-reperfusion such as occur during free flap procedures.

The zona pellucida (ZP) is a glycoprotein matrix surrounding mammalian oocytes. Upon fertilization, ZP hardening prevents sperm from binding to and penetrating the ZP. Here, we report that targeted gene deletion of the liver-derived plasma protein fetuin-B causes premature ZP hardening and, consequently, female infertility. Transplanting fetuin-B-deficient ovaries into wild-type recipients restores fertility, indicating that plasma fetuin-B is necessary and sufficient for fertilization. In vitro fertilization of oocytes from fetuin-B-deficient mice only worked after rendering the ZP penetrable by laser perforation. Mechanistically, fetuin-B sustains fertility by inhibiting ovastacin, a cortical granula protease known to trigger ZP hardening. Thus, plasma fetuin-B is necessary to restrain protease activity and thereby maintain ZP permeability until after gamete fusion. These results also show that premature ZP hardening can cause infertility in mice., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The utilization of a heart-lung machine (HLM) for the correction of congenital heart defects can lead to various complications, which can culminate in multiorgan failure and death. To reduce the considerable risk of complications, we developed a miniaturized, highly integrated HLM (MiniHLM) for use in infants and children. For the purpose of testing the MiniHLM, we developed a new rabbit animal model. In all, surgery was performed on 32 rabbits. In the first series, 13 New Zealand white rabbits were placed on cardiopulmonary bypass (CPB) for 1 hour with the use of an initial version of the MiniHLM. In the second series, we operated on 19 Chinchilla Bastard rabbits using the further developed MiniHLM 02 or the Dideco Kids D100 system. While several adjustments had to be made to the operating protocol in the first series in order to lower the mortality rate, 15 of the 19 rabbits were successfully weaned from the HLM in the second series. Blood tests pertaining to hemolysis and the expression of inflammation were performed. In addition, tissue samples were taken from the right atrial auricle for the purpose of investigating the expression of inflammatory parameters. The newly developed MiniHLM prototype was tested successfully in an animal model in terms of technical function, hemolysis, and the expression of inflammation. On account of the comparability of their blood values, as well as their anatomy, Chinchilla Bastard rabbits serve as excellent models for the testing of CPB and support systems for infants and children that do not require the administration of foreign blood.

Olfactory ensheathing cells (OEC) are a promising graftable cell population for improving functional outcomes after experimental spinal cord injury. However only few studies have focused on experimental models with large cavitations, which require bridging substrates to transfer and maintain the donor cells within the lesion site. Here, a state-of-the-art collagen-based multi-channeled three dimensional scaffold was used to deliver olfactory ensheathing cells to 2 mm long unilateral low-thoracic hemisection cavities. For a period of 10 weeks, allodynia of the hindpaws was monitored using the von Frey hair filament test, while an extensive analysis of motor ability was performed with use of the CatWalk gait analysis system and the BBB locomotor scale. No substantial improvement or deterioration of motor functions was induced and there was no effect on lesion-induced allodynia. On the basis of these data, we conclude that relatively large spinal cord lesions with cavitation may present additional hurdles to the therapeutic effect of OEC. Future studies are needed to address the nature that such lesion cavities place on cell grafts., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The prognosis for recipients of small liver grafts is poor. The aim of this study was to determine the impact of venous systemic oxygen persufflation (VSOP) with nitric oxide (NO) gas for 30% partial liver preservation and transplantation in rats. After we determined optimal NO concentration as 40 ppm in vitro with the isolated perfused rat liver model, we assessed liver injury and regeneration in vivo at 1, 3, 24 and 168 h after transplantation in the following three groups after 3 h-cold storage (n = 20 per group): control group = static storage; VSOP group = oxygen persufflation and VSOP+NO group = oxygen with NO persufflation. The liver graft persufflation was achieved with medical gas via the suprahepatic vena cava; In comparison with control group after transplantation, VSOP+NO preservation (1) increased portal circulation, (2) reduced AST and ALT release, (3) upregulated hepatic endothelial NO synthase, (4) reduced hepatocyte and bileductule damage and (5) improved liver regeneration. These results suggest that gaseous oxygen with NO persufflation is a novel and safe preservation method for small partial liver grafts, not only alleviating graft injury but also improve liver regeneration after transplantation., (© Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Orthopedic implants including engineered bone tissue are commonly tested in sheep. To avoid rejection of heterologous or xenogeneic cells, autologous cells are preferably used, that is, ovine mesenchymal stem cells (oMSC). Unlike human MSC, ovine MSC are not well studied regarding isolation, expansion, and characterization. Here we investigated the impact of culture media composition on growth characteristics, differentiation, and surface antigen expression of oMSC. The culture media varied in fetal calf serum (FCS) content and in the addition of supplements and/or additional epidermal growth factor (EGF). We found that FCS strongly influenced oMSC proliferation and that specific combinations of supplemental factors (MCDB-201, ITS-plus, dexamethasone, and L-ascorbic acid) determined the expression of surface epitopes. We compared two published protocols for oMSC differentiation towards the osteogenic, adipogenic, and chondrogenic fate and found (i) considerable donor to donor variations, (ii) protocol-dependent variations, and (iii) variations resulting from the preculture medium composition. Our results indicate that the isolation and culture of oMSC in different growth media are highly variable regarding oMSC phenotype and behaviour. Furthermore, variations from donor to donor critically influence growth rate, surface marker expression, and differentiation.

Middle cerebral artery occlusion (MCAO) models have become well established as the most suitable way to simulate stroke in experimental studies. The high variability in the size of the resulting infarct due to filament composition, rodent strain and vessel anatomy makes the setup of such models very complex. Beside controllable variables of homeostasis, the choice of anesthetics and the grade of ischemia and reperfusion played a major role for extent of neurological injury. Transient MCAO was induced during either isoflurane or ketamine/xylazine (ket/xyl) anesthesia with simultaneously measurement of cerebral blood flow (CBF) in 60 male Wistar rats (380-420 g). Neurological injury was quantified after 24 h. Isoflurane compared with ket/xyl improved mortality 24 h after MCAO (10 vs. 50 %, p = 0.037) and predominantly led to striatal infarcts (78 vs. 18 %, p = 0.009) without involvement of the neocortex and medial caudoputamen. Independent of anesthesia type, cortical infarcts could be predicted with a sensitivity of 67 % and a specificity of 100 % if CBF did not exceed 35 % of the baseline value during ischemia. In all other cases, cortical infarcts developed if the reperfusion values remained below 50 %. Hyperemia during reperfusion significantly increased infarct and edema volumes. The cause of frequent striatal infarcts after isoflurane anesthesia might be attributed to an improved CBF during ischemia (46 ± 15 % vs. 35 ± 19 %, p = 0.04). S-100β release, edema volume and upregulation of IL-6 and IL-1β expression were impeded by isoflurane. Thus, anesthetic management as well as the grade of ischemia and reperfusion after transient MCAO demonstrated important effects on neurological injury.

Background and Aims: Differential thoracic epidural regional block, also known as a differential neural block (DNB), involves the placement of an epidural catheter placed in the thoracic epidural space to achieve appropriate anesthesia in a dermatomal distribution. This is a retrospective case series evaluating how well a DNB may predict success of subsequent visceral blockade in patients with chronic abdominal pain of visceral origin., Methods: Of 402 patients who had a DNB performed for unexplained abdominal pain from January 2000 to January 2009, 81 patients were found to have results consistent with visceral pain and thus underwent subsequent visceral blockade. Basic demographic data, years of chronic pain, history of psychosocial issues, initial visual analog scale (VAS) pain score, pain location, and medication usage were documented in our electronic medical record database. Parameters regarding DNB and visceral blocks also were documented. Descriptive statistics were computed for all variables. The positive predictive value (PPV) for DNB for whom visceral block was successful (at least a 50% reduction in VAS) was calculated. Additionally, subjects with successful visceral blocks were compared to those with unsuccessful visceral blocks., Participants: All patients with chronic abdominal pain with normal gastrointestinal studies who underwent DNB., Setting: Tertiary Outpatient Pain Management Clinic., Design:   Retrospective Cohort Study., Results: Mean age of patients was 46 (± 15) years, 73% were female, and median duration of pain was 5 years. 67% of subjects were taking opioid analgesics. PPV of DNB was 70.4%. Only factor found to be statistically significant with visceral block success was baseline VAS with higher scores associated with DNB predictive success (6.8 ± 1.7 vs. 5.5, 1.8; P = 0.004). Use of membrane stabilizing medications was significantly more common in subjects for whom visceral block was not successful (46% vs. 25%; P = 0.058). Area underneath curve (AUC) for VAS was found to be 0.70 (95% CI: 0.57, 0.82), which signifies fair discrimination., Conclusion: Differential neural block is fairly predictive of subsequent visceral block success in patients with chronic abdominal pain of visceral origin. An initial VAS ≥ 5 provides a sensitivity of 93%, which implies that VAS < 5 may predict unsuccessful visceral block. Contrarily, a value of ≥ 8 would provide a specificity of 92% and may be used to predict success of subsequent visceral block., (© 2012 The Authors. Pain Practice © 2012 World Institute of Pain.)

The impact of surgical staplers on tissues has been studied mostly in an empirical manner. In this paper, finite element method was used to clarify the mechanics of tissue stapling and associated phenomena. Various stapling modalities and several designs of circular staplers were investigated to evaluate the impact of the device on tissues and mechanical performance of the end-to-end colorectal anastomosis. Numerical simulations demonstrated that a single row of staples is not adequate to resist leakage due to non-linear buckling and opening of the tissue layers between two adjacent staples. Compared to the single staple row configuration, significant increase in stress experienced by the tissue at the inner staple rows was observed in two and three rows designs. On the other hand, adding second and/or third staple row had no effect on strain in the tissue inside the staples. Variable height design with higher staples in outer rows significantly reduced the stresses and strains in outer rows when compared to the same configuration with flat cartridge., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The paper investigates both fresh porcine spleen and liver and the possible decomposition of these organs under a freeze-thaw cycle. The effect of tissue preservation condition is an important factor which should be taken into account for protracted biomechanical tests. In this work, tension tests were conducted for a large number of tissue specimens from twenty pigs divided into two groups of 10. Concretely, the first group was tested in fresh state; the other one was tested after a freeze-thaw cycle which simulates the conservation conditions before biomechanical experiments. A modified Fung model for isotropic behavior was adopted for the curve fitting of each kind of tissues. Experimental results show strong effects of the realistic freeze-thaw cycle on the capsule of elastin-rich spleen but negligible effects on the liver which virtually contains no elastin. This different behavior could be explained by the autolysis of elastin by elastolytic enzymes during the warmer period after thawing. Realistic biomechanical properties of elastin-rich organs can only be expected if really fresh tissue is tested. The observations are supported by tests of intestines., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Neuroprotective strategies after cardiopulmonary resuscitation are currently the focus of experimental and clinical research. Levosimendan has been proposed as a promising drug candidate because of its cardioprotective properties, improved haemodynamic effects in vivo and reduced traumatic brain injury in vitro. The effects of levosimendan on brain metabolism during and after ischaemia/hypoxia are unknown., Methods: Transient cerebral ischaemia/hypoxia was induced in 30 male Wistar rats by bilateral common carotid artery clamping for 15 min and concomitant ventilation with 6% O2 during general anaesthesia with urethane. After 10 min of global ischaemia/hypoxia, the rats were treated with an i.v. bolus of 24 μg kg-1 levosimendan followed by a continuous infusion of 0.2 μg kg-1 min-1. The changes in the energy-related metabolites lactate, the lactate/pyruvate ratio, glucose and glutamate were monitored by microdialysis. In addition, the effects on global haemodynamics, cerebral perfusion and autoregulation, oedema and expression of proinflammatory genes in the neocortex were assessed., Results: Levosimendan reduced blood pressure during initial reperfusion (72 ± 14 vs. 109 ± 2 mmHg, p = 0.03) and delayed flow maximum by 5 minutes (p = 0.002). Whereas no effects on time course of lactate, glucose, pyruvate and glutamate concentrations in the dialysate could be observed, the lactate/pyruvate ratio during initial reperfusion (144 ± 31 vs. 77 ± 8, p = 0.017) and the glutamate release during 90 minutes of reperfusion (75 ± 19 vs. 24 ± 28 μmol·L-1) were higher in the levosimendan group. The increased expression of IL-6, IL-1ß TNFα and ICAM-1, extend of cerebral edema and cerebral autoregulation was not influenced by levosimendan., Conclusion: Although levosimendan has neuroprotective actions in vitro and on the spinal cord in vivo and has been shown to cross the blood-brain barrier, the present results showed that levosimendan did not reduce the initial neuronal injury after transient ischaemia/hypoxia.

Background: The purpose of the present study was to quantify bacterial translocation to mesenteric lymph nodes due to different levels of intra-abdominal hypertension (IAH; 15 vs. 30 mmHg) lasting for 24 h in a porcine model., Methods: We examined 18 anesthetized and intubated pigs (52.3 ± 4.7 kg) which were randomly allocated to three experimental groups (each n = 6) and studied over a period of 24 h. After preparation and establishing a steady state, the intra-abdominal pressure (IAP) was increased stepwise to 30 mmHg in six animals using a carbon dioxide (CO2) insufflator (IAP-30 group). In the second group, IAP was increased to 15 mmHg (IAP-15 group), while IAP remained unchanged in another six pigs (control group). Using a pulse contour cardiac output (PiCCO®) monitoring system, hemodynamic parameters as well as blood gases were recorded periodically. Moreover, peripheral and portal vein blood samples were taken for microbiological examinations. Lymph nodes from the ileocecal junction were sampled during an intra-vital laparotomy at the end of the observational period. After sacrificing the animals, bowel tissue samples and corresponding mesenteric lymph nodes (MLN) were extracted for histopathological and microbiological analyses., Results: Cardiac output decreased in all groups. In IAP-30 animals, volumetric preload indices significantly decreased, while those of IAP-15 pigs did not differ from those of controls. Under IAH, the mean arterial pressure (MAP) in the IAP-30 group declined, while MAP in the IAP-15 group was significantly elevated (controls unchanged). PO2 and PCO2 remained unchanged. The grade of ischemic damage of the intestines (histopathologically quantified using the Park score) increased significantly with different IAH levels. Accordingly, the amount of translocated bacteria in intestinal wall specimens as well as in MLN significantly increased with the level of IAH. Lymph node cultures confirmed the relation between bacterial translocation (BT) and IAP. The most often cultivated species were Escherichia coli, Staphylococcus, Clostridium, Pasteurella, and Streptococcus. Bacteremia was detected only occasionally in all three groups (not significantly different) showing gut-derived bacteria such as Proteus, Klebsiella, and E. coli spp., Conclusion: In this porcine model, a higher level of ischemic damage and more BT were observed in animals subjected to an IAP of 30 mmHg when compared to animals subjected to an IAP of 15 mmHg or controls.

Introduction: Despite its presumed effectiveness and clinical use, the physiology of selective visceral perfusion combined with distal aortic perfusion during open thoracoabdominal aortic surgery has not been characterized. Thus, the aim of this study was to establish a translatable model of thoracic aortic-clamping to assess the effect of selective visceral perfusion with added distal aortic perfusion on local intestinal macrohemodynamics and microhemodynamics, intestinal histopathology, and markers of inflammation and intestinal damage., Methods: A thoracolaparotomy was performed in 15 pigs, and the aorta was exposed, including the origins of celiac trunk and superior mesenteric artery. The animals were divided into three cohorts: control (I), thoracic aortic cross-clamping (II), and thoracic aortic cross-clamping with selective visceral perfusion plus distal aortic perfusion using extracorporeal circulation (III). Macrocirculatory and microcirculatory blood flow was assessed by transit time ultrasound volume flow measurements and fluorescent microspheres. Intestinal ischemia-reperfusion injury was determined by the analysis of perioperative intestinal fatty acid-binding protein (IFABP) and interleukin-8 (IL-8) levels and correlated with histopathologic changes., Results: Severe intestinal tissue injury and an inflammatory response were observed in cohort II compared with cohort III for IL-8 (38.2 vs 3.56 pg/mL; P = .04). The procedure in cohort III resulted in a flow and pressure-associated intestinal hypoperfusion compared with cohort I in the superior mesenteric artery (mean blood pressure, 24.1 ± 10.4 vs 67.2 ± 7.4 mm Hg; P < .0001; mean flow rates: 353.3 ± 133.8 vs 961.7 ± 310.8 mL/min; P < .0001). This was paralleled in cohort III vs cohort I by a significant mucosal injury (IFABP, 713 ± 307.1 vs 170 ± 115.4 pg/mL; P = .014) despite a profound recruitment of intestinal microcirculation (338% ± 206.7% vs 135% ± 123.7%; P = .05)., Conclusions: This study reports a novel large-animal model of thoracic aortic cross-clamping that allows the study of visceral perfusion strategies. However, we demonstrated with IL-8 and IFABP measurements that thoracoabdominal aortic aneurysm surgery with selective visceral perfusion and distal aortic perfusion is superior to the clamp-and-sew technique, even though small intestinal tissue damage cannot be completely avoided by selective visceral perfusion and distal aortic perfusion. In any case, this model seems to be a platform to evaluate and optimize measures for gut wall protection., (Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

The increasing shortage of donor organs has led to the increasing use of organs from non-heart-beating donors. We aimed to assess the impact of venous systemic oxygen persufflation (VSOP) supplemented with nitric oxide (NO) gas during the cold storage (CS) of warm ischemia (WI)-damaged experimental liver grafts. Rat livers (n = 5 per group) were retrieved after 30 minutes of WI induced by cardiac arrest (the WI group) and were thereafter preserved for 24 hours by CS in histidine tryptophan ketoglutarate solution. During CS, gaseous oxygen was insufflated via the caval vein with 40 ppm NO (the VSOP-NO group) or without NO (the VSOP group). Cold-stored livers without WI served as controls. Liver viability was assessed after the preservation period by normothermic isolated reperfusion for 45 minutes with oxygenated Krebs-Henseleit buffer. After 45 minutes of reperfusion, the VSOP-NO-treated livers showed significantly lower alanine aminotransferase values than the WI-damaged livers (10.2 ± 0.2 versus 78.2 ± 14.6 IU/L), whereas the control livers showed no differences from the VSOP-NO-treated livers. The mitochondrial enzyme release was lower in the VSOP-NO group (4.0 ± 0.7 IU/L) versus the WI group (18.2 ± 4.9 IU/L). An increased portal vein pressure was observed throughout reperfusion (45 minutes) in the WI group (21.7 ± 0.2 mm Hg) versus the VSOP-NO group (12.2 ± 0.8 mm Hg) and the control group (19.9 ± 0.4 mm Hg). Furthermore, the NO concentration in the perfusate after 5 minutes of reperfusion was highest in the VSOP-NO group. The release of malondialdehyde into the perfusate was significantly reduced in the VSOP-NO group (0.9 ± 0.1 nmol/mL) versus the WI group (31.3 ± 5.3 nmol/mL). In conclusion, the resuscitation of livers after 30 minutes of WI to a level comparable to that of nonischemically damaged livers is possible with VSOP supplemented with NO gas. Moreover, the application of VSOP with NO minimizes the extent of injuries caused by oxygen free radicals during preservation., (Copyright © 2011 American Association for the Study of Liver Diseases.)

The use of bioengineered nerve guides as alternatives for autologous nerve transplantation (ANT) is a promising strategy for the repair of peripheral nerve defects. In the present investigation, we present a collagen-based micro-structured nerve guide (Perimaix) for the repair of 2 cm rat sciatic nerve defects. Perimaix is an open-porous biodegradable nerve guide containing continuous, longitudinally orientated channels for orientated nerve growth. The effects of these nerve guides on axon regeneration by six weeks after implantation have been compared with those of ANT. Investigation of the regenerated sciatic nerve indicated that Perimaix strongly supported directed axon regeneration. When seeded with cultivated rat Schwann cells (SC), the Perimaix nerve guide was found to be almost as supportive of axon regeneration as ANT. The use of SC from transgenic green-fluorescent-protein (GFP) rats allowed us to detect the viability of donor SC at 1 week and 6 weeks after transplantation. The GFP-positive SC were aligned in a columnar fashion within the longitudinally orientated micro-channels. This cellular arrangement was not only observed prior to implantation, but also at one week and 6 weeks after implantation. It may be concluded that Perimaix nerve guides hold great promise for the repair of peripheral nerve defects., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objectives: The aim of this study was to evaluate the use of model mandibles made preoperatively by additive manufacturing, which were used to prebend reconstruction plates prior to mandibular resection and reconstruction with microvascular bony flaps., Materials and Methods: Computer Tomography (CT) or Cone Beam Tomography (CBT) scans acquired preoperatively were used to obtain DICOM data sets to produce a model of the mandible using rapid prototyping. This model was used as a template to prebend and then sterilize a 2.3 or 2.7 reconstruction plate, which was used to reconstruct the mandible with a microvascular bony flap. This technique was used in 20 consecutive patients who required mandibular resection and reconstruction because of a tumour or osteoradionecrosis., Results: The prebent plate was used in all patients intraoperatively without the need for any further bending. The average time to bend a plate on a nonsterile model was 0.42 h (range 0.25-0.68 h). This is felt to represent the minimum amount of time saved during the operation. Additive manufacture of the mandible prior to resection and reconstruction with a microvascular flap is a useful technique which reduces the operating time., (Copyright © 2011 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

The creation of musculoskeletal tissue represents an alternative for the replacement of soft tissue in reconstructive surgery. However, most of the approaches of creating artificial tissue have their limitations in the size as the maximally obtainable dimension of bioartificial tissue (BAT) is limited due to the lack of supporting vessels within the 3-dimensional construct. The seeded myoblasts require high amounts of perfusion, oxygen, and nutrients to survive. To achieve this, we developed a 3-dimensional scaffold which features the epigastric artery as macroscopic core vessel inside the BAT in a rat model (perfused group, n = 4) and a control group (n = 3) without the epigastric vessels and, therefore, without perfusion. The in vivo monitoring of the transplanted myoblasts was assessed by bioluminescence imaging and showed both the viability of the epigastric artery within the 3-dimensional construct and again that cell survival in vivo is highly depending on the blood supply with the beginning of capillarization within the BAT seven days after transplantation in the perfused group. However, further studies focussing on the matrix improvement will be necessary to create a transplantable BAT with the epigastric artery as anastomosable vessel.

Objective: In this study, we investigated the efficacy of a fibrinogen/thrombin-coated collagen patch (TachoSil) to terminate severe bleeding in a coagulopathic pig model with blunt liver injury., Methods: Following surgical preparation, which included splenectomy and cystotomy, coagulopathy was induced by exchanging 80% of the animal's blood volume with hydroxyethylstarch 130/0.4 and lactated Ringer's solution. Subsequently, a grade III liver injury was induced by a force of 238 ± 19 Newton and free bleeding was allowed for 30 s. Animals were randomly assigned to receive either a placebo patch (cotton patch) (control group, n = 7) or a fibrinogen/thrombin patch (FT patch group, n = 7), which was positioned 30 s after injury on the inflicted area. Coagulation parameters, hemodynamic variables, as well as treatment were monitored for 2 h post-injury and patch placement. Histology was obtained to evaluate the equality of liver injury and to show the morphology of the FT patch., Results: Hemostasis after hemodilution was severely impaired. Blood loss after trauma was significantly diminished in the FT patch group (419 mL ± 90 mL) compared with the control group (1775 mL ± 358 mL) (P < 0.001). All animals treated with the FT patch survived, whereas 100% of the control group died before reaching the end of the observation period (P < 0.001). Gross sectioning and histology showed an equal degree of injury with a tight adherence of the FT patch., Conclusion: TachoSil under severe coagulopathy effectively controlled bleeding and successfully prevented hemorrhagic death., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Although prothrombin complex concentrate (PCC) is increasingly used for the treatment of trauma-induced coagulopathy, few studies have investigated the impact and safety of PCC for this indication. The present study was performed to assess PCC for treatment of coagulopathy after blunt liver injury under severe hypothermia. Coagulopathy in 14 anaesthetised pigs was induced by haemodilution. Subsequently, standardised blunt liver injury was induced under severe hypothermia (32.8-33.2°C). Animals were randomised to receive either PCC (35 IU kg⁻¹) or saline (control). Coagulation was assessed over the following 2 hours by thromboelastometry and thrombin generation. Internal organs were examined to determine presence of emboli. The administration of PCC showed a significant reduction in blood loss (p=0.002 vs. controls) and a significant increase in the rate of survival (p=0.022 vs. controls). Plasma thrombin generation in the PCC group increased considerably above baseline levels, with significant increases in peak thrombin levels and endogenous thrombin potential versus controls throughout the follow-up period. In addition, PT decreased significantly in the PCC group versus the control group. However, only slight improvements in thromboelastometry variables were observed. Histology showed an equal degree of liver injury in both groups, and no thromboembolism. In severely hypothermic pigs, the application of PCC corrected trauma-induced coagulopathy and reduced blood loss. Thus, the infusion of PCC might be a reasonable approach to reduce the need for blood cell transfusion in trauma. Furthermore, the impact and safety of PCC application can be monitored through thrombin generation and thromboelastometry under hypothermia.

Despite increasing use of prothrombin complex concentrate (PCC) to treat hemorrhage-associated coagulopathy, few studies have investigated PCC in trauma, and there is a particular lack of safety data. This study was performed to evaluate PCC therapy in a porcine model of coagulopathy with blunt liver injury. Coagulopathy was induced in 27 anesthetized pigs by replacing approximately 70% blood volume with hydroxyethyl starch 130/0.4 and Ringer's lactate solution; erythrocytes were collected and retransfused. Ten minutes after trauma, animals randomly received PCC (35 or 50 IU/kg) or saline. Coagulation parameters including thromboelastometry, thrombin generation, and blood loss were monitored for 2 hours. Internal organs were examined macroscopically and histologically to determine the presence of emboli and assess liver injury. Total blood loss was significantly lower and survival was higher in both PCC groups versus the control group (P < .05). These outcomes appeared to be dose-independent. Thromboembolism was found in all animals treated with 50 IU/kg PCC; 44% also showed signs of disseminated intravascular coagulation. Liver injury was similar in all animals. In conclusion, 35 IU/kg PCC safely improved coagulation and attenuated blood loss. However, the higher dose of PCC (50 IU/kg) appeared to increase the risk of thromboembolism and disseminated intravascular coagulation.

In order to reduce the number of animal experiments, the use of non-heart-beating donors (NHBDs) from a commercial abattoir has been proposed. Since the use of slaughterhouse organs is legally not defined as animal experiment, this would fulfil international standards as an alternative to animal experiments. The development of intravascular thrombosis after cardiac arrest negatively impacts organ preservation and thus viability during ischaemic storage and reperfusion. A fibrinolytic preflush with streptokinase might overcome these limitations. Therefore, the functional and histomorphological integrity of kidneys preserved immediately with intact circulation (control group A) and kidneys preserved after cardiac arrest with a 30 min period of warm ischaemia (WI) (group B) was compared with kidneys preflushed with 12.5 kU/L (group C) or 50 kU/L streptokinase (group D) after 30 min WI prior to preservation. We could demonstrate that kidneys preflushed with 12.5 kU/L streptokinase (group C) performed better than those without streptokinase pretreatment after WI (group B). Parameters like oxygen consumption, perfusion pressure, laboratory values, lactate dehydrogenase level and lipidperoxidation were closer to that of the control (group A) than in groups B and D. The higher streptokinase concentration of 50 kU/L (group D) resulted histologically in a more pronounced tissue damage and an attenuated renal function, indicating toxic effects. On the basis of our results we believe streptokinase preflushed slaughterhouse kidneys to be an adequate alternative to organs from laboratory animals with the potential to further reduce the number of animal experiments.

To assess the effect of the perfusion pressure (PP) during machine perfusion (MP) on the preservation quality of kidney grafts, we compared mean PPs of 25 and 30 mmHg using a porcine autotransplantation model. After assessment of the microcirculation, animals underwent left nephrectomy. Thereafter, kidneys were washed out followed by 20 h of MP at 25 mmHg (MP25, n = 7) or 30 mmHg (MP30, n = 7) using a novel MP system for hypothermic pulsatile perfusion. After MP preservation, the contralateral kidneys were removed and the preserved kidneys heterotopically autotransplanted. Ten minutes after reperfusion, the microcirculation was reassessed. Seven days posttransplant, animals were euthanized and the kidney grafts removed for histological analysis. MP using a mean PP of 25 mmHg resulted in higher capillary blood flow after reperfusion. In the MP30 group, 6 out of 7 animals survived, whereas in the MP25 group all animals survived. Overall, improvement in recovery of renal function and a better preservation of structural integrity were seen in the MP25 group compared to the MP30 group. Using a novel system for hypothermic MP, a mean PP of 25 mmHg is preferred over a mean PP of 30 mmHg.

Background/aims: Chronic organ donor shortage has led to the consideration to expand the donor pool with livers from non-heart-beating donors (NHBD), although a higher risk of graft dys- or nonfunction is associated with these livers. We examined the effects of selective cyclooxygenase-2 (COX-2) inhibition on hepatic warm ischemia (WI) reperfusion (I/R) injury of NHBD., Methods: Male Wistar rats were used as donors and meloxicam (5 mg/kg body weight) was administered into the preservation solution. Livers were excised after 60 min of WI in situ, flushed and preserved for 24 h at 4°C. Reperfusion was carried out in vitro at a constant flow for 45 min. During reperfusion (5, 15, 30 and 45 min), enzyme release of alanine aminotransferase and glutamate lactate dehydrogenase were measured as well as portal venous pressure, bile production and oxygen consumption. The production of malondialdehyde was quantified and TUNEL staining was performed. Quantitative PCR analyzed COX-2 mRNA. COX-2 immunohistochemistry and TxB(2) detection completed the measurements., Results: Meloxicam treatment led to better functional recovery concerning liver enzyme release, vascular resistance and metabolic activity over time in all animals. Oxidative stress and apoptosis were considerably reduced., Conclusion: Cold storage using meloxicam resulted in significantly better integrity and function of livers retrieved from NHBD. Selective COX-2 inhibition is a new therapeutic approach achieving improved preservation of grafts from NHBD., (Copyright © 2011 S. Karger AG, Basel.)

Background: The transcription factor Tcfap2c has been demonstrated to be essential for various processes during mammalian development. It has been found to be upregulated in various undifferentiated tumors and is implicated with poor prognosis. Tcfap2c is reported to impinge on cellular proliferation, differentiation and apoptosis. However, the physiological consequences of Tcfap2c-expression remain largely unknown., Methodology/principal Findings: Therefore we established a gain of function model to analyze the role of Tcfap2c in development and disease. Induction of the transgene led to robust expression in all tissues (except brain and testis) and lead to rapid mortality within 3-7 days. In the liver cellular proliferation and apoptosis was detected. Accumulation of microvesicular lipid droplets and breakdown of major hepatic metabolism pathways resulted in steatosis. Serum analysis showed a dramatic increase of enzymes indicative for hepatic failure. After induction of Tcfap2c we identified a set of 447 common genes, which are deregulated in both liver and primary hepatocyte culture. Further analysis showed a prominent repression of the cytochrome p450 system, PPARA, Lipin1 and Lipin2. These data indicate that in the liver Tcfap2c represses pathways, which are responsible for fatty acid metabolism. In the intestine, Tcfap2c expression resulted in expansion of Sox9 positive and proliferative active epithelial progenitor cells resulting in dysplastic growth of mucosal crypt cells and loss of differentiated mucosa., Conclusions: The transgenic mice show that ectopic expression of Tcfap2c is not tolerated. Due to the phenotype observed, iTcfap2c-mice represent a model system to study liver failure. In intestine, Tcfap2c induced cellular hyperplasia and suppressed terminal differentiation indicating that Tcfap2c serves as a repressor of differentiation and inducer of proliferation. This might be achieved by the Tcfap2c mediated activation of Sox9 known to be expressed in intestinal and hepatic stem/progenitor cell populations.

Hypothermia can be caused by anaesthesia and/or surgery and represents a daily challenge in the operating room. Experimental animal surgery settings typically use heating pads or warming blankets to maintain the rodent's body temperature during long-lasting experiments. Warming is crucial in small animal experiments because these animals quickly lose temperature due to their large body surface to body weight ratio. While establishing a left ventricular infarction model in rats, we inserted a rectal temperature probe. The heating pad's set point was 37°C. Although a dual set point control circuit should prevent overheating, we observed a maximum heating pad's surface temperature of 43°C between the animal's back and the surface of the heating pad. At the end of the experiments, which lasted up to 8 h, the animals showed severe haematuria and segmental kidney damage. We hypothesized that overheating of the heating pad and uneven distribution of temperature led to kidney damage. Therefore, the maximal temperature of commonly used heating pads must be tightly controlled to avoid overheating, which may cause kidney or tissue injury, may falsify the experimental data and could influence the study results.

Background: Recombinant factor VIIa (rFVIIa) has been successfully used in various clinical conditions to treat severe coagulopathy, but its efficacy may be affected by the underlying conditions. We therefore investigated the efficacy of rFVIIa treatment under conditions of hypofibrinogenaemia in a pig model of blunt liver injury., Methods: Severe haemodilution was instigated in four groups of seven anaesthetized pigs. Before inflicting liver injury, animals were assigned to receive either 70 mg kg(-1) fibrinogen (fibrinogen group) or placebo (control group). Thirty seconds after injury, rFVIIa (180 µg kg(-1)) (rFVIIa and fibrinogen+rFVIIa groups) or vehicle (control and fibrinogen groups) was administered. Haemodynamic variables, coagulation parameters, and blood loss were monitored for 2 h. Histology was examined to evaluate the presence of thrombi and the consistency of liver injury., Results: At the end of the observation period, total blood loss [median (range)] decreased in all intervention groups [fibrinogen: 1275 (1221-1439) ml, P=0.036; rFVIIa: 966 (923-1136) ml, P=0.008; fibrinogen+rFVIIa: 678 (475-756) ml, P=0.008] when compared with control animals [blood loss: 1752 (1735-2221) ml]. The mortality rate in the control group was 100%, whereas only 42% of fibrinogen-substituted animals died (P=0.023). All animals treated with rFVIIa or fibrinogen+rFVIIa (P<0.001) survived and no signs of thromboembolism were observed., Conclusions: rFVIIa under conditions of hypofibrinogenaemia exhibited a positive impact on coagulation parameters and a reduction in blood loss. These effects were significantly improved after prior substitution with fibrinogen.

We present a case of maxillary and orbital floor reconstruction with a microvascular fibula graft and an individualized titanium mesh. Both were planned virtually; templates were made by rapid prototyping. The postoperative computer tomography scans showed that the planned positions were achieved correctly. This case report illustrates maxillary reconstruction performed with a special template technique and demonstrates the possibilities of computer aided design/computer aided manufacturing (CAD/CAM) applications in reconstructive surgery.

There is a clear clinical requirement for the design and development of living, functional, small-calibre arterial grafts. Here, we investigate the potential use of a small diameter, tissue-engineered artery in a pre-clinical study in the carotid artery position of sheep. Small-calibre ( approximately 5 mm) vascular composite grafts were molded using a fibrin scaffold supported by a poly(L/D)lactide 96/4 (P(L/D)LA 96/4) mesh, and seeded with autologous arterial-derived cells prior to 28 days of dynamic conditioning. Conditioned grafts were subsequently implanted for up to 6 months as interposed carotid artery grafts in the same animals from which the cells were harvested. Explanted grafts (n = 6) were patent in each of the study groups (1 month, 3 months, 6 months), with a significant stenosis in one explant (3 months). There was a complete absence of thrombus formation on the luminal surface of grafts, with no evidence for aneurysm formation or calcification after 6 months in vivo. Histological analyses revealed remodeling of the fibrin scaffold with mature autologous proteins, and excellent cell distribution within the graft wall. Positive vWf and eNOS staining, in addition to scanning electron microscopy, revealed a confluent monolayer of endothelial cells lining the luminal surface of the grafts. The present study demonstrates the successful production and mid-term application of an autologous, fibrin-based small-calibre vascular graft in the arterial circulation, and highlights the potential for the creation of autologous implantable arterial grafts in a number of settings., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome are increasingly observed in patients with severe acute pancreatitis (SAP). The aim of this study was to investigate the effects of IAH on pancreatic histology and ultrastructure in a porcine model. We examined 16 intubated and anesthetized domestic pigs with a mean body weight of 50.6 (SD, 3.8) kg. Using a CO2 pneumoperitoneum, the intra-abdominal pressure was increased to 30 mmHg for an investigation period of 6 or 12 h (each study group n = 6). In the control group, the intra-abdominal pressure remained 3.9 (SD, 5.4) mmHg for 12 h. Additional Ringer's solution was infused to maintain cardiac output at the level of controls. After the observation period, specimens were taken for histological and ultrastructural analysis, and animals were killed. Cardiac output did not change when compared with control. Histologically, mild- to moderate-grade necrosis was observed after 12 h of IAH. In the ultrastructural analysis, leukocyte infiltration and swelling of endothelial cells were found. In the acinar cells of the exocrine pancreas, endoplasmic reticulum was dilated, and necrosis was noticed. Mitochondrial damage manifested as cisternal destruction with formation of large vacuoles. In this porcine model, 6 and 12 h of IAH resulted in light-microscopical and ultrastructural changes comparable to pancreatitis in humans. As SAP is often accompanied by IAH, the finding of the underlying study suggests a vicious cycle in which IAH may worsen pancreatitis. Ultimately, these findings are in favor of a decompression in patients with SAP and IAH.

Background: Cold storage using histidine-tryptophan-ketoglutarate (HTK) solution is used widely in clinical practice for the preservation of warm ischaemia-damaged kidney grafts. This study assessed the efficacy of pulsatile machine perfusion in combination with Polysol for the preservation of warm ischaemia-damaged kidney grafts., Methods: After induction of warm ischaemia by clamping of the left renal pedicle for 30 min, pigs were subjected to left nephrectomy. Thereafter, grafts were preserved for 20 h by cold storage with HTK (CS-HTK) or Polysol (CS-PS), or machine preservation with Polysol (MP-PS). Subsequently, contralateral kidneys were removed and preserved kidneys were transplanted. Control pigs underwent unilateral nephrectomy. Renal function was assessed daily for 1 week. Kidney biopsies were analysed for morphology and proliferative response., Results: Renal function of warm ischaemia-damaged grafts preserved using MP-PS was comparable to that of non-ischaemic controls. MP-PS and CS-PS groups showed improved renal function compared with the CS-HTK group, with more favourable results for MP-PS than for CS-PS. The proliferative response of tubular cells in the CS-HTK group was higher than in all other groups., Conclusion: This study demonstrated that the function of warm ischaemia-damaged kidney grafts after pulsatile perfusion preservation was comparable to that of non-ischaemic controls., ((c) 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.)

Introduction: The early application of fibrinogen could potentially reverse haemodilution-induced coagulopathy, although the impact of varying concentrations of fibrinogen to reverse dilutional coagulopathy has not been studied in vivo. We postulated that fibrinogen concentration is correlated with blood loss in a pig model of coagulopathy with blunt liver injury., Methods: Coagulopathy was induced in 18 anaesthetized pigs (32 +/- 1.6 kg body weight) by replacing 80% of blood volume with hydroxyethylstarch 130/0.4 and Ringer's lactated solution, and re-transfusion of erythrocytes. Animals were randomly assigned to receive either 70 mg kg-1 (F-70) or 200 mg kg-1 (F-200) fibrinogen or placebo before inducing blunt liver injury using a force of 225 +/- 26 Newton. Haemodynamics, coagulation parameters and blood loss were monitored for 2 hours. After death, histological examination of internal organs was performed to assess the presence of emboli and the equality of liver injury., Results: Plasma dilution caused severe coagulopathy. Measured by thromboelastography fibrinogen restored coagulation dose-dependently. Total blood loss was significantly lower and survival better in both fibrinogen groups as compared to controls (P < 0.05). Between the F-70 (1317 +/- 113 ml) and the F-200 group (1155 +/- 232 ml) no significant difference in total blood loss could be observed, despite improved coagulation parameters in the F-200 group (P < 0.05). Microscopy revealed even injury pattern and no (micro) thrombi for either group., Conclusions: Restoring fibrinogen with 70 or 200 mg kg-1 after severe dilutional coagulopathy safely improved coagulation and attenuated blood loss after experimental blunt liver trauma. The higher dosage of fibrinogen was not associated with a further reduction in blood loss.

Background: To elaborate the impact of new haemostatic agents we developed an instrument for the pressure-controlled induction of blunt liver injuries in a porcine animal model., Materials and Methods: A dilutional coagulopathy of 80% of animal blood volume was induced in 9 anaesthetized pigs. Animals were randomly assigned to be injured with a force of 112 Newton (N) (n = 1), 224 +/- 19 N (n = 4) or 355 +/- 35 N (n = 4). The impact of injury was measured by blood loss, survival time and coagulation parameters. Liver histology was obtained to evaluate the degree of liver injury., Results: The profound haemodilution resulted in a significant alteration of all coagulation parameters. After inflicting the injury with 355 +/- 35 N, both the survival time (30 +/- 9 min; p = 0.006) and blood loss (68 +/- 16 ml min(-1), p = 0.002) were significantly different as compared to injuries with 224 +/- 19 N (survival time: 76 +/- 20 min, blood loss: 23 +/- 4 ml min(-1)). In contrast, an injury with 112 N led to an insignificant blood loss of only 239 ml., Conclusion: We developed a pressure-controlled clamp that allows for the induction of blunt liver traumas with highly reproducible injuries with a positive correlation with blood loss and survival., (Copyright (c) 2009 S. Karger AG, Basel.)

Objective: The impact of different preservation solutions for washout of kidney grafts was evaluated regarding temperature, kidney weight, remaining red blood cells (RBCs) and histological evaluation after ex vivo washout using 500 mL cold preservation solution at 4 degrees C followed by 24 hours cold storage (CS)., Methods: Kidneys retrieved from Landrace pigs (20-30 kg) were immediately washed (warm ischemic time 0 min [WIT 0]), using 500 mL cold University of Wisconsin solution (UW), histidine-tryptophan-ketoglutarate (HTK), or Polysol (PS) followed by 24 hours, CS. Also, kidneys were retrieved after a WIT of 30 minutes followed by washout using HTK or PS., Results: After washout, the weight of kidneys washed out with HTK had increased, whereas that of organs in the UW or PS group had decreased. After washout with UW, the core temperature of WIT 0 kidneys was lower than that with HTK. The time needed for washout using 500 mL solution was shorter using PS compared with HTK for both WIT 0 and WIT 30 groups. The amount of remaining RBCs was similar between all WIT 0 groups; whereas in the WIT 30 groups the amount was higher in kidneys washed out using HTK compared with PS. Histological evaluation showed less tissue injury among PS-washed kidneys compared with UW or HTK., Conclusion: Overall, kidneys washed-out with PS showed better preservation of structural integrity after 24 hours, CS compared with either UW or HTK. Washout of warm ischemically damaged kidneys was more effective using PS compared with HTK.

Congenital heart surgery most often incorporates extracorporeal circulation. Due to foreign surface contact and the administration of foreign blood in many children, inflammatory response and hemolysis are important matters of debate. This is particularly an issue in premature and low birth-weight newborns. Taking these considerations into account, the Aachen miniaturized heart-lung machine (MiniHLM) with a total static priming volume of 102 mL (including tubing) was developed and tested in a small animal model. Fourteen female Chinchilla Bastard rabbits were operated on using two different kinds of circuits. In eight animals, a conventional HLM with Dideco Kids oxygenator and Stöckert roller pump (Sorin group, Milan, Italy) was used, and the Aachen MiniHLM was employed in six animals. Outcome parameters were hemolysis and blood gas analysis including lactate. The rabbits were anesthetized, and a standard median sternotomy was performed. The ascending aorta and the right atrium were cannulated. After initiating cardiopulmonary bypass, the aorta was cross-clamped, and cardiac arrest was induced by blood cardioplegia. Blood samples for hemolysis and blood gas analysis were drawn before, during, and after cardiopulmonary bypass. After 1 h aortic clamp time, all animals were weaned from cardiopulmonary bypass. Blood gas analysis revealed adequate oxygenation and perfusion during cardiopulmonary bypass, irrespective of the employed perfusion system. The use of the Aachen MiniHLM resulted in a statistically significant reduced decrease in fibrinogen during cardiopulmonary bypass. A trend revealing a reduced increase in free hemoglobin during bypass in the MiniHLM group could also be observed. This newly developed Aachen MiniHLM with low priming volume, reduced hemolysis, and excellent gas transfer (O(2) and CO(2)) may reduce circuit-induced complications during heart surgery in neonates.

Background: Delayed graft function (DGF) is defined as posttransplantation dialysis within 1 week, which might be associated with impaired long-term graft survival. The aim of our pilot study was to establish the ability of intraoperative spectrometry of allograft microperfusion to predict DGF., Methods: Twenty human kidney allografts transplanted from deceased donors were evaluated intraoperatively after reperfusion using modified organ spectrometry (O2C device). We examined hemoglobin oxygen saturation, intravascular amount of hemoglobin, and microperfusion flow/velocity., Results: Retrospectively, 10/20 (50%) allografts with measurable impairment of cortical hemoglobin oxygen saturation and microperfusion flow/velocity developed DGF. Retrospectively, we found that if the intravascular amount of hemoglobin was increased upon intraoperative measurement, the kidney was prone to develop DGF., Conclusions: Spectrometry data predicted DGF. Our results supported the thesis that impaired microperfusion is the key to DGF and might be related to postcapillary endothelial damage or intravascular sludge.

Unlabelled: Peripheral CD8 T-cell tolerance can be generated outside lymphatic tissue in the liver, but the course of events leading to tolerogenic interaction of hepatic cell populations with circulating T-cells remain largely undefined. Here we demonstrate that preferential uptake of systemically circulating antigen by murine liver sinusoidal endothelial cells (LSECs), and not by other antigen-presenting cells in the liver or spleen, leads to cross-presentation on major histocompatibility complex (MHC) I molecules, which causes rapid antigen-specific naïve CD8 T-cell retention in the liver but not in other organs. Using bone-marrow chimeras and a novel transgenic mouse model (Tie2-H-2K(b) mice) with endothelial cell-specific MHC I expression, we provide evidence that cross-presentation by organ-resident and radiation-resistant LSECs in vivo was both essential and sufficient to cause antigen-specific retention of naïve CD8 T-cells under noninflammatory conditions. This was followed by sustained CD8 T-cell proliferation and expansion in vivo, but ultimately led to the development of T-cell tolerance., Conclusion: Our results show that cross-presentation of circulating antigens by LSECs caused antigen-specific retention of naïve CD8 T-cells and identify antigen-specific T-cell adhesion as the first step in the induction of T-cell tolerance.

Objective: We sought to assess the efficacy of POLYSOL, a low-viscosity, colloid-based organ preservation solution, for the preservation of warm ischemically damaged kidney grafts compared with histidine-tryptophane-ketoglutarate (HTK) solution., Methods: Pigs (25-30 kg) underwent a left nephrectomy after clamping the renal vessels for 30 minutes. Kidney grafts washed out with Polysol (n = 6) or HTK (n = 6) were cold stored (CS) for 20 hours at 4 degrees C. After the preservation period, the contralateral kidney was removed and the preserved kidney implanted heterotopically. Renal function was assessed daily for 7 days. Thereafter, animals were killed and the kidney grafts removed for histologic analysis., Results: All animals survived for 7 days. All Polysol CS-preserved grafts showed immediate function, as demonstrated by urine production within 24 hours after reperfusion as compared with 3/6 grafts in the HTK CS group. Overall, the Polysol CS group showed improved renal function compared with HTK CS. Also, peak serum creatinine and blood urea values were lower in the Polysol CS group compared with HTK-preserved grafts. Histologic evaluation of warm ischemically damaged grafts showed less glomerular shrinking, less tubular damage, less edema, less inflammatory infiltration, and less necrosis in Polysol compared with HTK-preserved grafts., Conclusion: Application of Polysol solution for washout and CS preservation of warm ischemically damaged kidney grafts resulted in improved renal function and structural integrity when compared with HTK.

Resident muscularis macrophages initiate an inflammatory cascade during ischemia/reperfusion that is associated with dysmotility and the activation of immunologic processes. We hypothesized that these muscularis macrophages may also play a potential immunologic role for acute allograft rejection in intestinal transplantation. Orthotopic SBTx (BN-Lew) was performed without immunosuppression. Animals were sacrificed 7 days after SBTx. The role of resident macrophages was evaluated by transplantation of macrophage-depleted and gadolinium chloride-treated gut. Leukocyte infiltration was investigated in muscularis whole mounts by immunohistochemistry. Mediator mRNA expression was determined by Real-Time-RT-PCR. Apoptosis was evaluated by TUNEL. Smooth muscle contractility was assessed in a standard organ bath. In comparison to vehicle-treated grafts, macrophage-depleted grafts exhibited significantly lower mediator mRNA peak expression (IL-6, IL-2, IL-10, MCP-1, iNOS, TNFalpha, IFNgamma, FasL), leukocyte infiltrates (ED1- and ED2 positive monocytes and macrophages, neutrophils, CD4(+) and CD8(+) lymphocytes), apoptosis rates and an improved histologic rejection grading. Vehicle-treated grafts showed a 77% decrease in smooth muscle contractility compared to naïve controls, while macrophage-depleted gut exhibited only a 51% decrease in contractile activity. Transplantation of macrophage-depleted gut attenuates the functionally relevant molecular and cellular immunologic response within the graft muscularis in acute allograft rejection. Resident macrophages participate in initiating these processes.

The early diagnosis of colorectal cancer (CRC) is central for effective treatment, as prognosis is directly related to the stage of the disease. Development of tumor markers found in the blood from patients, which can detect CRC at an early stage, should have a major impact in morbidity and mortality of this disease. The nuclear matrix is the structural scaffolding of the nucleus and specific nuclear matrix proteins (NMPs) have been identified as an "fingerprint" for various cancer types. Previous studies from our laboratory have identified four colon cancer associated NMPs termed colon cancer-specific antigen (CCSA)-2 to (CCSA)-5. The objective of the present study was to analyze the expression of one of these proteins, CCSA-2 in serum from various patient populations and to determine whether CCSA-2 antibodies could be used in a clinically applicable serum-based immunoassay specifically to detect colon cancer. Using an indirect ELISA, which detects CCSA-2, the protein was measured in the serum from 174 individuals, including healthy individuals, patients with colon cancer, patients with diverticulosis, colon polyps, inflammatory bowel disease (IBD) as well as other cancer types. With a predetermined cutoff absorbance of 0.6 OD we have successfully utilized this approach to develop an immunoassay that detected colon cancer. The immunoassay showed a sensitivity of 88.8% (24/27) and an overall specificity of 84.2% (106/127). This initial study showed the potential of CCSA-2 to serve as a highly specific blood based marker for colon cancer. Although potentially promising, the results of this study must be confirmed in larger independent validation studies.

Background: Most experimental therapy studies are performed in mice that bear subcutaneous or orthotopic hepatoma but are otherwise healthy. We questioned whether a pre-existing fibrosis affects tumour development of implanted syngenic hepatoma cells. To further investigate a selected panel of factors involved in tumour growth, tumour organ samples were characterized for gene expression of vascular endothelial growth factor (VEGF)-A/-C, VEGF receptors Flt1, Flk-1, Flt-4 and for VEGF-A protein levels., Results: The presented data show that tumour sizes were 3.7-fold increased and fibrotic livers had numerous satellites. Increased tumour sizes were associated with elevated intratumoral VEGF-A protein amounts and intratumoral increased VEGF receptor gene expression levels in tumour tissue from fibrotic livers as compared with non-fibrotic livers. Additionally, intratumoral gene expression levels of matrix metalloproteinase-2 (MMP-2) and MMP-9 were elevated in fibrotic mice., Conclusion: Our results indicate that liver fibrosis stimulates tumour development of implanted syngenic hepatoma cells. Accelerated tumour growth was going along with elevated intratumoral VEGF-A and VEGF-A receptor status, which most probably mediated pro-angiogenic and prometastatic effects in this model. Furthermore, advanced tumour spread was associated with increased MMP-2/-9 expression. These data suggest that the intratumoral VEGF-A proteins levels and VEGF receptor status contribute to accelerated hepatocellular carcinoma development in fibrotic mice and that elevated MMP-2, MMP-9 and VEGF-C levels could promote tumour metastasis in this model.

Aim: The object of this study was to provide evidence for a time-reduced diagnostic space in multiple trauma patients by use of a digital X-ray system in the emergency suite., Method: The same algorithm was used in the first attention of 66 severely injured patients. For 21 patients from October 2000 to March 2001 (group 1) conventional X-rays (thorax, pelvis, spine and extremities) were performed in the analogue way, for 45 patients from April to December 2001 (group 2) the new digital system (Philips Optimum and Philips PCR AC 500) was used., Results: The two groups were similar concerning age, sex and injury severity. The time-space from the patient's delivery in the emergency suite to the handing over in the operation theatre or intensive care unit was significantly lower in group 2 (87 +/- 33 min, p < 0.001) than in group 1 (121 +/- 49 min)., Conclusion: Digital imaging with conventional X-rays in the first attention of multiple trauma patients reduces the diagnostic time by more than half an hour, when applying the same diagnostic algorithm.

The purpose of this study was to analyse cartilage changes after traumatic meniscal lesions and to provide a detailed description of the model used with a view to reducing the number of animals used in future studies. The sheep's knee was chosen, as ovine biomechanics are similar to that of humans. In two groups of 10 animals each, a radial tear in the medial meniscus was either sutured with polydioxanone (PDS) or left untreated (sham-operated). Half of the animals in each group were sacrificed after six months, the other half after one year. The time periods to achieve weight bearing, meniscus healing, joint effusion (magnetic resonance imaging scan) and knee cartilage in the medial, lateral and patellofemoral compartments were evaluated in comparison to the opposite knee (control). Osteoarthritis (OA) was assessed by a modified Outerbridge classification and confirmed by scanning electron microscopy. Only one sutured meniscus remained completely adapted. In all other meniscus lesions, the rupture healed with a scar. In the PDS and sham-operated groups, OA was significantly higher in the medial knee compartment than in the lateral compartment and in controls (P < 0.001). In the operated groups, joint effusion was higher in the right hindlimb knee than in the normal left hindlimb knee (control) after six and 12 months (P < 0.001). Non-treated, displaced and even adapted sutured radial ovine meniscus tears produced intense OA within less than six months. Therefore, this animal model is suitable for assessment of new therapeutic regimens in meniscal surgery.