Allogeneic donor split skin grafts for treatment of refractory ulcers in cutaneous chronic graft-versus-host disease after allogeneic hematopoietic stem cell transplantation-a retrospective analysis on seven patients.

Refractory skin ulcers due to severe chronic graft-versus-host disease (cGVHD) remain to be associated with significant morbidity and mortality.We performed an allogeneic donor skin transplantation in seven adult patients after allogeneic hematopoietic stem cell transplantation for cGVHD-associated refractory skin ulcers. While four patients received a split skin graft (SSG), in one patient, a full thickness skin graft for two small refractory ulcers of the ankle was performed, and one patient received in vitro expanded donor keratinocyte grafts derived from hair roots of the original unrelated donor. In one additional patient, a large deep fascial defect of the lower leg was covered with an autologous greater omentum free graft before coverage with an allogeneic SSG. An additional patient was treated with an autologous scrotal skin graft for a refractory ulcer associated with deep sclerosis of cGVHD after unrelated donor transplantation.All skin grafts engrafted and resulted in permanent coverage of the grafted ulcers without any signs of immunological mediated damage. In the patient receiving in vitro expanded keratinocyte grafts, two localized ulcers were permanently covered by donor skin while this approach failed to cover extensive circular ulcers of the lower legs.Allogeneic donor skin grafts are a valuable treatment option in refractory ulcers due to cGVHD but are restricted mainly to related donors while keratinocyte grafts from unrelated donors remain experimental. In male patients lacking a related donor, autologous scrotal skin graft may be an alternative option.

Vascular malformations of upper and lower extremity - from radiological interventional therapy to surgical soft tissue reconstruction - an interdisciplinary treatment.

This article presents our experience in managing peripheral vascular malformations of upper and lower extremities over a 4-year period in a series of 46 patients of the Department of Plastic Surgery treated in the Interdisciplinary Center of Vascular Anomalies (ICVA) at the University of Regensburg. The patients presented vascular malformations of upper and lower extremity and were selected from our prospective vascular anomalies file archive from 2012 to 2016. During this period in the ICVA at University of Regensburg were performed more than 1400 radiological interventional treatments in patients with vascular malformations.The purpose of this retrospective study was to review combined embolotherapy, sclerotherapy (embolo/sclerotherapy), and surgical procedures (surgical excision and soft tissue reconstruction) to manage vascular malformations. Treatments were principally induced to reduce pain, daily physical limitations, social discomfort and recover tegument continuity after ulceration.The 46 patients were first examined with noninvasive radiological procedures. After diagnosis was posed, embolo/sclerotherapy, surgical procedures and clinically as well as radiological follow-ups were coordinated and established by the multidisciplinary team. All vascular malformations were categorized according to the classification approved at the April 2014 General Assembly of International Society for the Study of Vascular Anomalies (ISSVA) in Melbourne, Australia. Arteriovenous malformations (AVMs) were further classified following the Cho-Do and Schobinger classification.Embolo/sclerotherapy shows to be the most appropriate procedure in vascular malformations treatment. Nevertheless was found that in case of complications or lack of improvement as well as to improve functional or aesthetical results, a following partial or complete surgical excision and immediate soft tissue reconstruction seems to be the gold-standard treatment. In addition, the precise clinical and radiological diagnosis as well as an intensive postoperative patient care have a significant positive influence on the clinical outcome and patient satisfaction while decreasing morbidity and recurrence during early and late follow-up.Vascular malformations require a multidisciplinary approach and individual treatment after complex excision and indispensable reconstruction.

New reconstruction for bone integration of non-vascularized autogenous bone graft with better bony union and revascularisation.

INTRODUCTION: Phalangeal defects are often seen after tumor resection, infections, and in complex open hand fractures. In many cases, reconstruction is difficult and amputation is performed to avoid prolonged rehabilitation that is often associated with a poor outcome. In these cases, the maintenance of length and function presents a reconstructive challenge. METHODS: We reviewed 11 patients who underwent extensive phalangeal reconstruction with non-vascularized bone graft from the iliac crest using a key-in-slot-joint technique to provide acceptable function and bony union. RESULTS: In each case, non-vascularized bone graft with a length of 1.4-6.0 cm was used to reconstruct the phalanx. Follow-up ranged from 6 weeks to 5 months, and in all cases, there was bony union after 6 weeks. We evaluated range of motion, function, and as well pain and grip strength of the fingers. CONCLUSIONS: This case series suggests that a key-in-slot technique allows non-vascularized bone graft to be used in complex large phalangeal bone defects. Due to better bone contact, a sufficient perfusion and revascularisation of the non-vascularized bone graft can be achieved for a quicker and stable bony union. This method appears to be an alternative to amputation in selected cases with a satisfactory soft-tissue envelope.

Transepidermal oxygen flux during arterial occlusion using ratiometric luminescence imaging.

BACKGROUND: A physiological oxygen transport through a circulatory and microcirculatory system is essential for execution of cellular functions. Several pathological conditions e.g. infections, ischemia, cancer, diabetes, hypertension or chronic wounds show a change of oxygen distribution and oxygen tension in cellular microenvironment. Additionally complex operative procedures in order to reconstruct tissue defects require a reliable monitoring of microcirculation. OBJECTIVE: Target of this study was to evaluate skin oxygenation during an ischemia-reperfusion experiment using transepidermal oxygen flux imaging. METHODS: Twelve patients at the Department of Plastic and Reconstructive surgery of the University hospital of Regensburg underwent to elective hand operations. During the operation a tourniquet is standardly set on the upper arm to create ischemia in order to facilitate the operative procedure. Measurements were performed at the different time intervals: in rest, under ischemia and after reperfusion. RESULTS: The transepidermal oxygen flux increased during the ischemic condition compared to normal condition and decreased to a lower value during reperfusion (rest: 0.043±0.007, ischemia: 0.063±0.014, reperfusion: 0.030±0.028). CONCULSION: Transepidermal oxygen flux imaging by ratiometric luminescence imaging seems to be a reliable tool to assess skin oxygenation. However dynamic changes seem to be more informative than absolute thresholds. Further investigations are necessary to prove these promising results.

Transepidermal oxygen flux measurement - First clinical application for postoperative wound monitoring.

BACKGROUND: Measurement of skin oxygen is of great interest in diverse fields of medicine. Different pathologies, e.g. infection, ischemia cancer or chronic wounds show a characteristic oxygen distribution and skin oxygen tension. Additionally diverse operative procedures require a reliable postoperative monitoring in order to ensure success of the therapy. OBJECTIVE: Aim of this study was to assess transepidermal oxygen flux for postoperative wound monitoring after operative treatment of fractures close to the hip. METHODS: 22 patients underwent transepidermal oxygen flux measurement at the first postoperative day. Transepidermal oxygen flux measurement was performed using ratiometric luminescence imaging. Examination was conducted in close proximity to the operation wound. The corresponding area at the contralateral side served as reference. RESULTS: Oxygen flux in the operation area was higher (0.084±0.021) than the contralateral side (0.071±0.029). CONCLUSIONS: Transepidermal oxygen flux imaging by ratiometric luminescence imaging seems to be a reliable tool to assess postoperative wound healing. However further investigations in greater populations and under pathologic conditions have to be performed to prove these first results.

Circulating serum CK level vs. muscle impairment for in situ monitoring burden of disease in Mdx-mice.

BACKGROUND: Duchenne muscular dystrophy (DMD) consists of a lack in the expression of the subsarcolemmal protein dystrophin causing progressive muscle dysfunction. Among the widely applied animal models in DMD research is the C57BL/1010ScSn-Dmdmdx mouse, commonly referred to as the "mdx mouse". The potential benefit of novel interventions in this model is often assessed by variables such as functional improvement, histological changes, and creatine kinase (CK) serum levels as an indicator for the extent of in situ muscle damage. OBJECTIVE: Our objective was to determine to what extent the serum CK-level serves a surrogate for muscle dysfunction. METHODS: In this trial mdx mice were subjected to a four-limb wire-hanging test (WHT) to assess the physical performance as a reference for muscle function. As CK is a component of the muscle fiber cytosol, its serum activity is supposed to positively correlate with progressing muscle damage. Hence serum CK levels were measured to detect the degree of muscle impairment. The functional tests and the serum CK levels were analyzed for their specific correlation. RESULTS: Although physical performance decreased during the course of the experiment, latency to fall times in the WHT did not correlate with the CK level in mdx mice. CONCLUSION: Our data suggests that the serum CK activity might be a critical parameter to monitor the progression of muscle impairment in mdx mice. Further this study emphasizes the complexity of the DMD phenotype in the mdx mouse, and the care with which isolated parameters in this model should be interpreted.

[Surgical reconstructive procedures of the chest wall after mediastinitis]. / Plastische Rekonstruktionsverfahren der Brustwand nach Mediastinitis.

Sternal osteomyelitis as a direct consequence of advanced mediastinitis or as in most cases after median sternotomy is still associated with a prolonged hospital stay, increased morbidity and postoperative mortality. Early diagnosis and an adequate surgical treatment are decisive for the prognosis. Prerequisites for a secondary stabilization of the chest wall using wires or plates are sterile wound conditions. Diverse reconstructive techniques are available for anterior chest wall reconstruction depending on the defect size and localization. The various reconstructive methods including local and free flap coverage are described in this review article.

Vascularized transfer of two coherent toe joints in simultaneously reconstructing MCP and PIP of a mutilated finger.

BACKGROUND: The reconstruction of metacarpal- and interphalangeal joints after severe hand injuries has been proven to be challenging. Commonly used procedures like arthrodesis, amputation or ray resection of the finger compromise the functionality of the injured finger. Especially for young patients, the restoration of all functions of the fingers is a priority. Local tissue transfers for finger joint reconstructions is not an option due to inacceptable donor site morbidity; microsurgical tissue transfers in terms of free toe joint transfers have proven to be a valuable method. METHODS: We present the case of a patient who suffered an excessive injury from a circular saw to his dominant hand. The MCP Joints of D2-D4 were fully destroyed, along with the PIP joint of a subtotally amputated D4. Arteries, nerves and tendons could be coapted directly, while primarily reconstructing of the finger joints was impossible. To ensure a possible regain of full functionality, two coherent joints, the MTP and the PIP of one toe, were transferred to the ring finger as a single transplant, reconstructing the MCP and the PIP joints of the injured finger in a one step procedure. Additionally the MCP joint of the D2 was reconstructed by the use of a free PIP-joint transfer, further the MCP joint of the D3 was replaced by an MCP endoprosthesis. RESULTS: After a follow up of 3 years the patient displayed full function of his dominant hand including sensitivity, and has gone back to manual work without limitations. The result was cosmetically acceptable and the donor site defect was easily being tolerated by the patient who is playing soccer in the regional soccer league. CONCLUSION: Free double toe joint transfer has been proven feasible in this patient. While transferring a single toe joint to reconstruct a finger joint is a well-established method, our review of the latest literature showed no case of a free transfer of two coherent joints and three transplanted joints in one hand. The applied microsurgical technique should be considered by microsurgically trained hand surgeons for the treatment of comparable severe hand injuries. In comparison to the most common procedures described for the repair and reconstruction of severely injured finger joints this method showed superior results.

Contrast enhanced ultrasound (CEUS) - an unique monitoring technique to assess microvascularization after buried flap transplantation.

OBJECTIVE: Incidence of patients requiring complex soft tissue or osseous reconstruction has dramatically increased. However most of the monitoring systems have limitations in tissue penetration and are not able to detect microvascular complications after transplantation of so-called buried-flaps, that have no contact to the surface.Aim of the study was to assess contrast enhanced ultrasound (CEUS) as monitoring tool after buried flap transplantations. METHODS: 20 patients were examined after buried flap transplantation using CEUS. Quantitative perfusion analysis (TIC) was performed with an integrated perfusion software using stored cine-loops. Two perfusion-parameters, time to PEAK (TtoPk) and area under the curve (Area), were evaluated using TIC analysis. RESULTS: Minor complications were observed in 3 patients. In these patients a delayed contrast agent wash-in and wash-out was observed. Additionally the perfusion values TtoPk (sec.) and Area (relative Units) were clearly different in the patients with minor complications: TtoPk: 32.0 sec; Area 425.5 rU (without complication), TtoPk: 38.6 sec.; Area: 18.3 rU (wound healing disturbance) and TtoPk: 14.4 sec.; Area: 105.9 rU (hematoma). CONCLUSION: As CEUS can assess microvascularization almost depth-independent, CEUS is an unique method to assess global flap perfusion after buried flap transplantation.

Quantitative Assessment of Free Flap Viability with CEUS Using an Integrated Perfusion Software.

PURPOSE: New treatment strategies in oncology and trauma surgery lead to an increasing demand for soft tissue reconstruction with free tissue transfer. In previous studies, CEUS was proven to detect early flap failure. The aim of this study was to detect and quantify vascular disturbances after free flap transplantation using a fast integrated perfusion software tool. MATERIAL AND METHODS: From 2011 to 2013, 33 patients were examined by one experienced radiologist using CEUS after a bolus injection of 1-2.4 ml of SonoVue(®). Flap perfusion was analysed qualitatively regarding contrast defects or delayed wash-in. Additionally, an integrated semi-quantitative analysis using time-intensity curve analysis (TIC) was performed. TIC analysis of the transplant was conducted on a centimetre-by-centimetre basis up to a penetration depth of 4 cm. The 2 perfusion parameters "Time to PEAK" and "Area under the Curve" were compared in patients without complications vs. patients with minor complications or complete flap loss to figure out significant differences. TtoPk is given in seconds (s) and Area is given in relative units (rU) Results: A regular postoperative process was observed in 26 (79%) patients. In contrast, 5 (15%) patients with partial superficial flap necrosis, 1 patient (3%) with complete flap loss and 1 patient (3%) with haematoma were observed. TtoPk revealed no significant differences, whereas Area revealed significantly lower perfusion values in the corresponding areas in patients with complications. The critical threshold for sufficient flap perfusion was set below 150 rU. CONCLUSION: In conclusion, CEUS is a mobile and cost-effective opportunity to quantify tissue perfusion and can even be used almost without any restrictions in multi-morbid patients with renal and hepatic failure.

Evidence based postoperative treatment of distal radius fractures following internal locking plate fixation.

Originally, the treatment method of choice for distal radial fractures (DRF) has been a non-operative approach with six to eight weeks of plaster casting. The introduction of volar locking plate systems at the beginning of the 21 st century has pushed trends towards open reduction and internal fixation (ORIF). While the introduction of fixed angle locking plates together with the increasing knowledge on wrist function and related variable outcomes has led to consensus that operative fixation in instable DRF is the treatment method of choice, there is no agreement on a postoperative care of these injuries. The authors will discuss the available evidence for current concepts of postoperative treatment of DRFs following fixed angle fixation under socioeconomical, biomechanical and burden of disease aspects. Further, relevant randomized controlled trials are evaluated with regard to applied postoperative treatment regimes and related risks for complications.

Pressure monitoring during lipofilling procedures.

BACKGROUND: Grafting of autologous lipoaspirate for various clinical applications has become a common procedure in clinical practice. With an estimated mortality rate of 10-15 percent, fat embolism is among the most severe complications to be expected after lipofilling therapies. OBJECTIVE: The aim of this study was to determine the level of interstitial pressure after the injection of defined volumes of lipoaspirate into the subcutaneous tissue of female breasts. It was hypothesized, that interstitial pressure levels exceed the physiologic capillary pressure during lipofilling procedures and hence increase the potential risk for fat embolism. Further it was investigated if external tissue expansion has the potential to significantly reduce interstitial tissue pressure. METHODS: Interstitial pressure was monitored in 36 female patients, that underwent autologous fat injections into the breast. Measurements were conducted with a sensor needle connected to a pressure transducer (LogiCal Pressure Monitoring Kit, Smiths medical int. Ltd., UK). Patients were divided into 4 subcohorts differing in their pre-treatment regimen or local tissue conditions. Pre-treatment consisted of tissue expansion, achieved with the Brava™ (Brava LLC Miami, Fla., USA) vacuum-chamber. RESULTS: The increase in interstitial pressure after injection volumes of 100 ml (p = 0.006), 200 ml (p = 0.000) and between 100 ml and 200 ml (p = 0.004) respectively, were significant in non-mastectomized patients without pre-treatment. Patients pre-treated with Brava™ did not show such statistically significant differences in interstitial pressures before and after the injection of 100 ml and 200 ml of lipoaspirate (p = 0.178). The difference in interstitial pressure in mastectomized patients between 0 ml and 100 ml (p = 0.003), as well as 0 ml and 200 ml (p = 0.028) was significant. The difference in pressures between pre-treated patients and patients without pre-treatment did not differ significantly in the mastectomized patient cohort. CONCLUSION: During lipofilling procedures interstitial pressures are reached that exceed pressure limits defined as hazardous for fat embolism. To date it is unknown what pressure levels need to be considered critical for complications in soft tissue interventions. Further the results indicate higher interstitial pressures for patients that had undergone mastectomy, whereas pre-treatment with external tissue expansion seemed to diminish pressure values.

Postoperative monitoring of local and free flaps with contrast-enhanced ultrasound (CEUS)--analysis of 112 patients.

PURPOSE: Tissue defects are a common problem in trauma surgery and oncology. Flap transplantation is often the only therapy to cover such defects. Several monitoring systems are currently available but none has made it to the clinical routine. The aim of this study was to assess perfusion disturbances of local and free flaps using contrast-enhanced ultrasound (CEUS). MATERIALS AND METHODS: 112 patients were examined during the first 72 hours after operation. CEUS was performed by one experienced examiner with a linear transducer (6 - 9 MHz, LOGIQE9/GE) after a bolus injection of 2.4 ml sulfohexa-fluoride microbubbles (SonoVue®, Bracco, Italy). Retrospective vascular perfusion was quantified by evaluating the stored DICOM cine loops using the perfusion software QONTRAST® (Bracco, Italy). Over a total penetration depth of 3 cm, every centimeter was analyzed separately. 27 complications were observed. Complete flap loss was only seen in 4 cases, while 23 flaps had to undergo minor revision and survived. RESULTS: Regarding the complete flap size, quantitative analysis showed significantly higher perfusion values in patients without complications compared to patients with complications: PEAK 16.5 vs. 10.0 (p = 0.001), TTP 32.6 vs. 22.2 (p = 0.001), RBV: 738.8 vs. 246.2 (p < 0.001), RBF 17.5 vs. 10.1 (p < 0.001) and MTT 43.1 vs. 29.5 (p = 0.001). Analysis of the correlation of the different flap types, age, sex and etiology of the tissue defect to the complication rate showed no statistical correlation. CONCLUSION: CEUS was capable of detecting vascular disturbances after flap transplantation. TTP, RBV and MTT seem to be the most accurately parameters and are not susceptible to malfunction during measurement.

[Angiogenesis and vascularisation in adipose tissue engineering]. / Angiogenese und Vaskularisation beim Tissue Engineering von Fettgewebe.

The current standard for the reconstruction of large soft tissue defects with exposed bone, nerves or blood vessels, for example after extensive tumor resections, complex injuries, severe burns or infections, is the local or free microsurgical tissue transfer. Despite the development of new surgical techniques and many synthetic materials, there are still a large number of limitations and complications at the donor and recipient site. Thus, in a subset of patients either complete treatment is not possible or poses problems. Therefore, there is a great need for the development of new methods and materials allowing for a permanent replacement with body own soft tissue. A promising therapeutic approach is the soft tissue replacement with autologous adipose tissue. Innovative research on the reconstruction of soft tissue by adipose tissue, and clinical and experimental studies on the long-term survival and transplantation of autologous adipose tissue showed that the free fat tissue graft without direct vascular connection come along with disappointing results. Often a loss of volume or a complete resorption of the graft because of insufficient tissue quality by lack of cell differentiation was observed. This fact points to the special role of the maintenance and development of the graft's blood supply (angiogenesis and vascularization) crucial for maintaining a constant volume of the tissue. The rapidly growing interdisciplinary field of tissue engineering offers alternative solutions to the existing treatment options with the aim to produce autologous adipose tissue, stable in volume in vitro as well as in vivo, which can be transplanted as a permanent tissue replacement to corresponding parts of the body. Numerous studies have demonstrated the important and most critical factor of vascularisation for quality, volume and long-term survival of transplanted newly generated adipose tissue constructs. Although our understanding of the regulatory mechanisms of adipogenesis is still limited, there are clear indications that the complex sequences of cell interactions in the differentiation and proliferation of adipocytes is directly related to angiogenesis.

The secretion pattern of perivascular fat cells is different from that of subcutaneous and visceral fat cells.

AIMS/HYPOTHESIS: We have previously found that the mass of perivascular adipose tissue (PVAT) correlates negatively with insulin sensitivity and post-ischaemic increase in blood flow. To understand how PVAT communicates with vascular vessels, interactions between perivascular, subcutaneous and visceral fat cells with endothelial cells (ECs) were examined with regard to inflammatory, metabolic and angiogenic proteins. To test for possible in vivo relevance of these findings, circulating levels of the predominant secretion product, hepatocyte growth factor (HGF), was measured in individuals carefully phenotyped for fat distribution patterns. METHODS: Mono- and co-cultures of human primary fat cells with ECs were performed. mRNA expression and protein production were studied using Luminex, cytokine array, RealTime Ready and ELISA systems. Effects of HGF on vascular cells were determined by WST assays. In patients, HGF levels were measured by ELISA, and the mass of different fat compartments was determined by whole-body MRI. RESULTS: In contrast with other fat cell types, PVAT cells released higher amounts of angiogenic factors, e.g. HGF, acidic fibroblast growth factor, thrombospondin-1, serpin-E1, monocyte chemotactic protein-1 and insulin-like growth factor-binding protein -3. Cocultures showed different expression profiles from monocultures, and mature adipocytes differed from pre-adipocytes. HGF was preferentially released by PVAT cells and stimulated EC growth and smooth muscle cell cytokine release. Finally, in 95 patients, only PVAT, not visceral or subcutaneous mass, correlated independently with serum HGF levels (p = 0.03; r = 0.225). CONCLUSIONS: Perivascular (pre-)adipocytes differ substantially from other fat cells with regard to mRNA expression and protein production of angiogenic factors. This may contribute to fat tissue growth and atherosclerotic plaque complications. Higher levels of angiogenic factors, such as HGF, in patients with increased perivascular fat mass may have pathological relevance.

The influence of nitric oxide synthase 2 on cutaneous wound angiogenesis.

BACKGROUND: Inducible nitric oxide synthase (nitric oxide synthase 2, NOS 2) inhibition significantly suppresses chronically ischaemic skin flap survival, possibly because of reduced angiogenesis. OBJECTIVES: To investigate the effect of genetic NOS 2 inhibition on cutaneous wound angiogenesis in two in vivo murine models. The impact of NOS 2 manipulation on vascular endothelial growth factor (VEGF)-A stimulated and fibroblast growth factor (FGF)-2 stimulated angiogenesis was also investigated in the Matrigel(®) plug assay. METHODS: (i) Matrigel plugs/incisional wounds: two groups of NOS 2-/- mice and two groups of wild-type (WT) mice had bilateral Matrigel plugs containing 500 ng mL(-1) VEGF-A or 1000 ng mL(-1) FGF-2 injected subcutaneously in the abdomen. A 2·5 cm long dorsal incisional skin wound was created and sutured closed in the same animals. Wounds and plugs were explored at 7 or 12 days. (ii) Excisional wounds: dorsal 0·5 × 1·0 cm excisional skin wounds were created in four groups (two NOS 2-/- and two WT) and explored at 7 or 14 days. Wounds and Matrigel plugs were examined histologically and morphometrically for determination of percentage vascular volume (PVV). RESULTS: The PVV in NOS 2-/- incisional wounds and excisional wounds was significantly less than in WT wounds (P = 0·05 and P < 0·001, respectively). The PVV was significantly less in VEGF-A stimulated Matrigel plugs compared with FGF-2 stimulated plugs in NOS 2-/- mice (P < 0·01), but not in WT mice. CONCLUSIONS: NOS 2 is significantly involved in angiogenic signalling in healing skin wounds, particularly within the first 7 days. However, Matrigel plug vascularization suggests that the role of NOS 2 in angiogenesis is related to VEGF-A but not FGF-2 stimulated angiogenesis.

[Comparison of hand surgery in the German and Italian DRG systems]. / Vergleich der Handchirurgie im deutschen und italienischen DRG-System.

Diagnosis-related groups (DRGs) are a patient classification system grouping related types of patients treated to the resources they consumed. In this analysis we compared the Italian and the German DRG systems regarding hand surgery with an emphasis on reimbursement of clinical cases. The 15 most common hand surgical diagnoses and their corresponding operative treatment in our clinic in 2009 were processed using a DRG grouper. The underlying data were transferred to the Italian system. Thus, the length of stay and the reimbursement of both countries could be obtained and compared. The latter was adjusted and corrected by the purchasing power of each country. The mean of the upper threshold of length of stay was 10 days in the German as well as the Italian system whereas the median was 2 times higher in Italy (6 vs. 12 days). Fifteen out of 19 cases showed higher reimbursement in Germany. The case mix index (CMI) of 0.917 in Germany represents a mean payment of 2,676 € per case. In Italy the hypothetical CMI of 0.635 resulted in a mean reimbursement of 1,853 € per case. The biggest difference in remuneration could be found for replantation of multiple fingers. For this service the German health-care system pays 12,320 € more than the Italian. Total proceeds of the top 15 diagnoses applying the number of cases treated in our clinic revealed 1.7 million € in the German and 1.2 million € in the Italian DRG system. Considering the purchasing power utilizing consumer prize parities, the difference of reimbursement between the countries decreased to 300,000 €. There is no mean length of stay per DRG in Italy, only the upper threshold of length of stay is determined. In most cases the latter is higher in Italy compared to Germany. The consumption of resources for finger replantation is not adequately represented in the Italian DRG system compared to finger amputation. Reimbursement of inpatient care is influenced by multiple factors not being subject to the free market economy. For this reason only descriptive comparison is feasible.

HERG1 gene expression as a specific tumor marker in colorectal tissues.

INTRODUCTION: Colorectal carcinomas exhibit a frequent recurrence after curative surgery, which may partially be due to histopathologically inconspicuous minimal residual disease. Reliable markers for tumor cells in colorectal tissue are still missing. Therefore, in this study we compared the predictive value of the putative tumor markers carcinoembryonic antigen (CEA), cytokeratin-19 (CK19) and cytokeratin-20 (CK20) to that of a novel marker, the human ether-a-go-go-related gene (HERG1) K(+) channel, a suggested regulator of tumor cell proliferation. MATERIALS AND METHODS: Using RT-PCR we studied HERG, CEA, CK19 and CK20 expression in colorectal carcinomas and non-carcinoma controls. HERG1 immunhistochemistry was performed in a total of 66 specimens, in colorectal carcinoma (n = 23), in matched histopathologically negative samples (n = 23) taken near the excision site from the same tumor patients and in healthy control biopsies (n = 20). In order to verify the relevance of HERG1 for tumor proliferation we studied the effect of HERG1 inhibition in the Colo-205 colon cancer carcinoma cell line using the MTT-assay. RESULTS: HERG1 was expressed in all tumor samples regardless of their stage and in adenomas larger than 0.4 cm, but absent in small adenomas, sigmadiverticulitis specimen and healthy histopathologically negative samples, except for one which developed a tumor recurrence. In contrast, CEA, CK19 and CK20 were absent in some tumors. The selective HERG1 inhibitor E-4031 dose-dependently impaired tumor growth in the proliferation assays. DISCUSSION: Our data indicate that HERG1, but not CEA, CK19 or CK20, is a highly sensitive and reliable tumor biomarker that may constitute a novel molecular target for tumor treatment.

Reversal of multidrug resistance and increase in plasma membrane fluidity in CHO cells with R-verapamil and bile salts.

Studies with multidrug resistance modifiers indicate that perturbations of the cell membrane structure may influence P-glycoprotein (P-gp)-mediated drug transport. We describe studies of plasma membrane order using electron-paramagnetic resonance (EPR) in resistant (CH(R)C5) and sensitive (AUXB1) chinese hamster ovary cells treated with R-verapamil and bile salts. Cell growth rates were determined in presence of doxorubicin mitomycin and cisplatin. The plasma membrane order in untreated resistant cells was higher than in the sensitive cells. Both the bile salt taurochenodeoxycholate (TCDC; 0.2-1.6 mM) and R-verapamil (1-3 microM) lowered the membrane order in the CH(R)C5 cells to that in the sensitive cells and reversed the resistance to doxorubicin and mitomycin. The bile salt tauroursodeoxycholate (TUDC; 0.2-3 mM) did not lower membrane order and did not sensitise CH(R)C5 cells. Neither R-verapamil, TCDC nor TUDC reduced the membrane order of the sensitive cells AUXB1 cells. These results support the view that changes in multidrug resistance in Chinese hamster ovary cells and P-gp function are associated with alterations in the fluidity of the plasma membrane.

Resistance modulation in CHO cells by R-verapamil and bile salts is associated with physical and chemical changes in the cell membrane.

OBJECTIVES: Changes in multidrug resistance by resistance modifiers such as R-verapamil cause changes in fluidity of the cell membrane. The extent to which these changes involve structural alterations in membrane lipids has been investigated in CHO cells. METHODS: Sensitive (AUXB1) and resistant (CH(R)C5) chinese hamster ovary cells (CHO) were grown in culture. Incubations were carried out with R-verapamil (0-10 microM) or the membrane perturbing agents tauro-cheno-deoxycholate (0-1.6 mM, TCDC) and tauro-urso-deoxycholate (0-3.5mM, TUDC). Cell membrane fluidity was determined by electron-paramagnetic resonance spectroscopy and membrane lipids by HPLC and TLC. RESULTS: The resistant CH(R)C5 subline had a higher cell membrane order (lower fluidity, S = 0.7234) in the interface region of the cell membrane than sensitive AUXB1 cells (S = 0.6984) determined using EPR. The MDR-modulator R-verapamil and TCDC, but not TUDC, lowered cell membrane order in a concentration-dependent manner and increased membrane fluidity of the resistant CH(R)C5 subline. TCDC and R-verapamil were without effect on the cell membrane fluidity of AUXB1 cells. These changes were accompanied by alterations in the fatty acid composition of the plasma membrane. Untreated sensitive AUXB1 cells had higher levels of unsaturated fatty acids than resistant CH(R)C5 cells. In CH(R)C5 cells, R-verapamil increased the content of poly-unsaturated fatty acids and TCDC, but not TUDC, increased the content of mono-unsaturated fatty acids. CONCLUSIONS: The results demonstrate that resistance modifiers such as verapamil may influence cytostatic drug action by producing structural changes to lipid domains in the plasma membrane.