Exercise therapy for chronic symptomatic peripheral artery disease

All guidelines worldwide strongly recommend exercise as a pillar of the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended for clinicians to promote and assist for the set-up of comprehensive exercise programmes to best advice in patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are narratively described based on the current best evidence. The document ends by highlighting disparities in access to supervised exercise programmes across Europe and the series of gaps for evidence requiring further research.

Exercise therapy for chronic symptomatic peripheral artery disease

All guidelines worldwide strongly recommend exercise as a pillar in the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended to promote and assist the set up of comprehensive exercise programmes and best advice for patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are described based on the current best evidence. The document ends by highlighting supervised exercise programme access disparities across Europe and the evidence gaps requiring further research.

Exercise Therapy for Chronic Symptomatic Peripheral Artery Disease: A Clinical Consensus Document of the European Society of Cardiology Working Group on Aorta and Peripheral Vascular Diseases in Collaboration With the European Society of Vascular Medicine and the European Society for Vascular Surgery

All guidelines worldwide strongly recommend exercise as a pillar in the management of patients affected by lower extremity peripheral artery disease (PAD). Exercise therapy in this setting presents different modalities, and a structured programme provides optimal results. This clinical consensus paper is intended to promote and assist the set up of comprehensive exercise programmes and best advice for patients with symptomatic chronic PAD. Different exercise training protocols specific for patients with PAD are presented. Data on patient assessment and outcome measures are described based on the current best evidence. The document ends by highlighting supervised exercise programme access disparities across Europe and the evidence gaps requiring further research.

Evaluation of the benefit of rivaroxaban on VOYAGER PAD primary composite of limb, heart and brain outcomes using the global rank and win ratio methods

Background/Introduction

The VOYAGER PAD trial demonstrated that rivaroxaban 2.5 mg twice daily added to background antiplatelet therapy reduced a composite of irreversible harm events of the heart limb and brain versus placebo in patients with symptomatic peripheral artery disease (PAD) after lower extremity revascularization. The primary analysis was performed as time to first event with equal weighting of components including fatal and non-fatal events.

Purpose

Traditional time to event analyses of composites generally assess outcomes with equal weights. Analyses evaluating outcomes using ranked or weighted methods may provide clinicians a mechanism to interpret results including different weighting and enable shared decision making with patients.

Methods

Exploratory analyses of the primary composite outcome were prespecified prior to trial completion/database lock. Two previously described approaches to evaluate composite outcomes by ranking or weighting were utilized. The first was the global rank method which includes ranking all components of the composite by order of clinical importance (Table 1) with a primary and alternative ranking prespecified. Each patient is assigned a rank with the worse rank for worse outcome and for patients with the same outcome, those occurring earlier assigned the worse rank. Van Elteren test for differences between groups was applied stratified by type of procedure and clopidogrel use consistent with the primary trial analysis. The second was the unmatched win ratio method according to Pocock's rule which ranked CV death higher than non-fatal events and then compared pairs of subjects, one from each treatment group for wins and losses for wins and losses as outlined in Table 1. Finkelstein and Schoenfeld statistics were utilized with confidence intervals provided from bootstrapping.

Results

A total of 6564 patients were randomized and all outcomes through the common study end date were counted. The global rank method using both the primary and alternative method yielded a statistically significant superior effect of rivaroxaban versus placebo (p-value for primary ranking 0.0158, p-value for alternative ranking 0.0155). When using the win-ratio approach, there were more wins for rivaroxaban (14.8%) than placebo (12.8%) with 72.4% of patients having no primary component events (Figure 1). The overall win ratio was 1.16 95% CI (1.03–1.30) in favor of rivaroxaban with p=0.0167.

Conclusion(s)

Rivaroxaban significantly reduces acute limb ischemia, amputation, MI, ischemic stroke or CV death in PAD after lower extremity revascularization. Exploratory analyses of this efficacy composite show consistent superiority either when considered as a ranked hierarchy of outcomes with CV death as the worst or whether considering a win-ratio approach ranking CV death as worse followed by non-fatal events. These data support the robustness of the primary trial results when considering ranking of the composite components.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Bayer

Comparative analysis of biofilm models to determine the efficacy of antimicrobials

Biofilms are one of the greatest challenges in today's treatment of chronic wounds. While antimicrobials kill platonic bacteria within seconds, they are rarely able to harm biofilms. In order to identify effective substances for antibacterial therapy, cost-efficient, standardized and reproducible models that aim to mimic the clinical situation are required. In this study, two 3D biofilm models based on human plasma with immune cells (lhBIOM) or based on sheep blood (sbBIOM) containing S. aureus or P. aeruginosa, are compared with the human biofilm model hpBIOM regarding their microscopic structure (scanning electron microscopy; SEM) and their bacterial resistance to octenidine hydrochloride (OCT) and a sodium hypochlorite (NaOCl) wound-irrigation solution. The three analyzed biofilm models show little to no reaction to treatment with the hypochlorous solution while planktonic S. aureus and P. aeruginosa cells are reduced within minutes. After 48 h, octenidine hydrochloride manages to erode the biofilm matrix and significantly reduce the bacterial load. The determined effects are qualitatively reflected by SEM. Our results show that both ethically acceptable human and sheep blood based biofilm models can be used as a standard for in vitro testing of new antimicrobial substances. Due to their composition, both fulfill the criteria of a reality-reflecting model and therefore should be used in the approval for new antimicrobial agents.

[Wound networks in Germany: structure, functions and objectives 2014]

BACKGROUND

Wound networks are structured collaborations between various professions and medical disciplines in the field of treatment of patients with chronic wounds. In view of the complex chronic courses of such wounds with many relevant underlying diseases, comorbidities and a multitude of possible therapy options, the evidence-based structured treatment of patients with wound problems is of particular importance. However, this treatment is very heterogeneous and often uncoordinated.

OBJECTIVE

This article describes a stocktaking of the active regional wound networks in Germany with characterization of their structures, activities and objectives.

METHODS

A nationwide survey was carried out targeting wound specialists and wound societies as well as already established wound networks for which an updating was carried out. All identified networks were issued with a standardized questionnaire about the size of the network, extent of regional coverage, participating medical disciplines and professional groups and activities. In addition to the preformulated questions, free text information was also encouraged.

RESULTS

A total of 35 wound networks could be identified. The majority of networks consisted of representatives of hospitals as well as physicians in private practice and nursing personnel. The most frequently represented medical disciplines were vascular surgeons (74%), general physicians (63%), diabetologists (60%), general surgeons (60%) and dermatologists (57%). The most frequent activities were informal meetings on further education (77%), exchange of experiences and second opinions (both 71%) and consultation on patient treatment (69%). Selective contracts were only implemented in very few cases.

CONCLUSION

The wound networks established in Germany on self-initiatives represent strong interdisciplinary and interprofessional-oriented specialist platforms with a high potential for structured and efficient treatment. Incentives for systematic utilization of these structures in the course of improvements in quality and remuneration of treatment of patients with chronic wounds would be desirable.

[Vascular medicine needs more evidence: recent results and meta-analyses for the treatment of diabetic feet]

BACKGROUND

This overview comments on clinical trials and meta-analyses from the literature on the treatment of diabetic feet.

METHODS

For the literature review, the MEDLINE database (PUBMED) was searched under the key words "diabetic foot". Publications of the last three years (2012 to 2014) were extracted.

RESULTS

For patients with diabetic feet, both endovascular (ER) and open (OR) revascularisation techniques are possible. There are not sufficient data to demonstrate whether open bypass surgery or endovascular interventions are more effective in these patients. However, registries show that ER has now in terms of quantity become the preferred method. Angiosome-targeted revascularisation has to be considered in these situations. For the local treatment of a diabetic foot ulcer a variety of dressings are available, the evidence for their recommendation is low. Dressing cost and the wound management properties, e.g. exudate management therefore can influence the choice of dressing. There is no evidence that more expensive dressings as compared to basic dressings offer advantages in terms of healing. In plantar diabetic foot ulcers, non-removable off-loading devices regardless of type are more likely to result in ulcer healing than removable off-loading devices, presumably, because patient compliance with off-loading is facilitated. Meaningful pressure-relieving interventions for treating diabetic foot ulcers also include Achilles tendon lengthening, a plantar fascia release and percutaneous flexor tenotomy. The value of a standardised treatment protocol carried out by a specialist team could be proven in large registries based on decreasing amputation rates.

CONCLUSION

This survey reveals a significant disparity between the large number of treatment recommendations and their evidence. For the future, therefore it is imperative to implement nationwide register surveys with respect to treatment and outcome of these patients.

[Cost and cost-effectiveness in the treatment of peripheral arterial occlusion disease - what is proven?]

BACKGROUND

This overview comments on the health-care relevance of peripheral arterial occlusive disease (PAOD) in patients with intermittent claudication (IC) and critical limb ischaemia (CLI). We evaluated different treatment modalities in terms of cost-effectiveness.

METHOD

For the literature review, the Medline database (PubMed) was searched under the key words "critical limb ischemia AND cost", "critical limb ischemia AND economy", "peripheral arterial disease AND cost", "peripheral arterial disease AND economy".

RESULTS

In the years 2005 to 2009, the hospitalisations of patients with PAOD rose disproportionately in Germany by 20 %, to 483,961 hospital admissions. By comparison, hospital admissions altogether increased by only 8 %. The average in-patient costs were estimated to be approximately € 5000 per PAOD-patient - a rather conservative estimate. For the patient with IC the economic data position is clear, supervised exercise training is by far the most cost-effective treatment option, followed by percutaneous transluminal angioplasty (PTA) and finally the peripheral bypass. In accordance with the guidelines of the UK, the latter is therefore indicated only if PTA fails or is technically not possible. In patients with CLI, the situation is not obvious. Indeed, a short-term economic advantage can be calculated for the PTA, the long-term comparison of both methods, however, is impossible due to insufficient data. In addition, the risk factors for the patient have to be included in the calculation. This was indeed demonstrated in the short-term, but could not be analysed in the long-term follow-up.

CONCLUSION

The issue of greater cost-effectiveness of open or endovascular treatment in patients with CLI is uncertain, the studies and patient populations are too heterogeneous. Further studies are urgently needed to structure the sequence of the various treatment options in guidelines and clinical pathways.

[Transcardiac Access Routes for Endovascular Treatment of Ascending Aortic Pathologies]

Gold standard for treatment of pathologies of the ascending aorta is still open surgery with extracorporal circulation in moderate to deep hypothermia. These procedures are associated with high morbidity and mortality, especially if performed in older patients or after previous cardiac surgery. Thoracic endovascular aortic repair (TEVAR) has become the preferred treatment option for thoracic aortic pathologies of the descending aorta even in high-risk patients with severe comorbidities resulting in reduced morbidity and mortality compared to open repair. Despite the continuous development of endograft technology an adequate arterial access still poses a relevant limitation of this treatment option accentuated in the proximal segments of the aorta. The transfemoral access may be limited due to severe kinking or arteriosclerotic plaque stenosis of femoral or iliac vessels. Furthermore, the long distance between femoral access vessels and the aortic lesion impairs device torsibility and exact deployment of the stent graft. To provide a practical alternative endovascular access to the ascending aorta, antegrade transcardiac access routes including transapical or transseptal techniques have recently gained increasing interest.

[Future vascular medicine: inauguration of a cardiovascular hybrid concept]

The demographic developments will lead to an exponential increase of cardiovascular diseases. Additionally, technical developments of conservative and invasive treatment modalities will be added to distinguished, organ-orientated therapeutic concepts. This will also require a new orientation of vascular services. This concept implies that specific contents are referred to and contained in partner specialties. Since the heart and vascular system function as an anatomic and functional union, implementation of vascular medicine within cardiovascular centres represents a logical consequence.

Advanced endovascular techniques for thoracic and abdominal aortic dissections

Endovascular treatment of aortic dissection is still in its infancy and consists usually of implantation of thoracic tubular stent-grafts to cover the proximal entry tear and redirect flow into the true lumen. Large registries comparing endovascular treatment by thoracic endovascular aortic repair (TEVAR) with open surgery for aortic dissection of the descending aorta have demonstrated a clear benefit for endovascular treatment with lower mortality and morbidity rates turning TEVAR into the standard treatment for complicated type B aortic dissection. With this momentum of success endovascular techniques continue to challenge open surgical techniques also in the aortic arch and the ascending aorta. TEVAR for aortic dissection has become more complex requiring an individualized treatment strategy as endovascular techniques have developed with the advent of new devices and increased experience of the operators. In many cases straight implantation of a thoracic tubular stent-graft is sufficient. But as rerouting of the blood flow can also change perfusion of vital side-branches the endovascular operator needs to have a large armamentarium of techniques and adjunctive procedures in order to sufficiently address the individual patient morphology. This chapter reviews a variety of endovascular techniques including access techniques, proximal sealing, the Petticoat-technique, false lumen deployment, fenestration techniques, branch vessel stenting and false lumen obstruction by various techniques.

New surgical and hybrid techniques for crural and pedal anastomoses

Although there is currently a trend using endovascular methods to treat long and/or complex distal lesions, there are some interesting new approaches, technical modifications and simplifications in open surgery. Some of these are new, and some are older, but their effectiveness is now starting to be recognized. 1) Anatomical concepts: the lower leg/foot consists of 6 angiosomes, which are supplied by the 3 main arteries. It has been shown that the revascularization of the correct angiosome could lead to a higher rate of success when compared to the connection of an indirect artery. Other anatomical concepts describe the use of a flow-thru flap, and the advances in the use of homografts in peripheral bypass surgery. 2) New materials for implantation: while biological graft materials (tissue engineering) are still under development, no fundamental changes in clinical use have taken place. If autologous vein is missing, alloplastic materials made from polyester or polytetrafluorethylene (PTFE) are the available alternatives. On the basis of studies published so far, heparin coating does appear to offer advantages. 3) New aids for operative treatment: in contrast to rather slow (clinical) advancement with regard to bypass materials, there have been some interesting developments with regard to ancillary products. There are clips for stapled anastomoses, small shunts or thermosensitive polymers to avoid clamping. Furthermore some techniques perform anastomoses without sewing, like intraluminal protein tubes or ring anastomoses. The Viabahn Padova Sutureless (ViPS) technique anastomoses a stent-graft to the artery by placing it openly into the vessel and then releasing a stent by a simple pulling mechanism. In summary, peripheral bypass surgery remains a very standardized operation. Although not spectacular, there are some interesting new approaches, technical modifications and simplifications.

[Change in concept--from vascular centre to interdisciplinary organ-oriented clinic for vascular medicine]

Demographic developments have led to an exponential increase of cardiovascular illness. Additionally, the technical development of conservative and invasive treatment modalities has added to an increase of differentiated therapy. The development of vascular centres led to optimised processes in diagnostic and therapy according to their essential requirements. A further development is an increased specialisation and new orientation of vascular specialties through a combination of vascular surgery, endovascular therapy and angiology. The concept of the Hamburg model implements this development by introduction of an organ-orientated clinic for vascular medicine, located within the heart centre of the University of Hamburg's Eppendorf Hospital.

[Ultrasoud screening in abdominal aortic aneurysm--numbers, data, facts]

There are increasing numbers of elective surgeries not only for abdominal aortic aneurysm repair but also for emergencies because of ruptured aneurysms (rAAA). Mortality rates of rAAA up to 40-50% have remained unchanged for years. Because of the elevated incidence of complications in rAAA, the overall mortality is at least 80% and shows a dismal prognosis for this group of patients. With ultrasonography, a cost-efficient, technically simple and safe method with high sensitivity is available for detecting abdominal aortic aneurysms. On the basis on an electronic Medline literature search and evaluation of data from the "voluntary quality assurance for abdominal aortic aneurysms 2008" of the German Society of Vascular Surgery (Deutsche Gesellschaft für Gefäßchirurgie und Gefäßmedizin DGG), this review presents critical analysis of the efficacy and cost-efficiency of an ultrasound-based screening programme for the early detection of abdominal aortic aneurysms. In this systematic review of the literature on AAA screening, a description of epidemiology and current situation concerning AAA in Germany will be given. The evaluation of 4 randomised studies for ultrasonic AAA screening is discussed and the recommendations of the German Society of Vascular Surgery concerning screening for AAA are highlighted.

Hyperbaric oxygen therapy for chronic wounds

BACKGROUND

Chronic wounds are common and present a health problem with significant effect on quality of life. The wide range of therapeutic strategies for such wounds reflects the various pathologies that may cause tissue breakdown, including poor blood supply resulting in inadequate oxygenation of the wound bed. Hyperbaric oxygen therapy (HBOT) has been suggested to improve oxygen supply to wounds and therefore improve their healing.

OBJECTIVES

To assess the benefits and harms of adjunctive HBOT for treating chronic ulcers of the lower limb (diabetic foot ulcers, venous and arterial ulcers and pressure ulcers).

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Trial Register (searched 6 February 2003), CENTRAL (The Cochrane Library Issue 1, 2003), Medline (1966 - 2003), EMBASE (1974 - 2003), DORCTHIM (1996 - 2003), and reference lists of articles. Relevant journals were handsearched and researchers in the field were contacted.

SELECTION CRITERIA

Randomised studies comparing the effect on chronic wound healing of therapeutic regimens which include HBOT with those that exclude HBOT (with or without sham therapy).

DATA COLLECTION AND ANALYSIS

Three reviewers independently evaluated the quality of the relevant trials using the validated Oxford-Scale (Jadad 1996) and extracted the data from the included trials.

MAIN RESULTS

Five trials contributed to this review. Diabetic foot ulcer (4 trials, 147 patients): Pooled data of three trials with 118 patients showed a reduction in the risk of major amputation when adjunctive HBOT was used, compared to the alternative therapy (RR 0.31, 95% CI 0.13 to 0.71). Sensitivity analysis for the allocation of dropouts did not significantly alter that result. This analysis predicts that we would need to treat 4 individuals with HBOT in order to prevent 1 amputation in the short term (NNT 4, 95% CI 3 to 11). There was no statistically significant difference in minor amputation rate (pooled data of two trials with 48 patients). Healing rates were reported in one trial (Abidia 2003) which showed a significant improvement in the chance of healing 1 year after therapy (RR for failure to heal with sham 2.3, 95%CI 1.1 to 4.7, P=0.03), although no effect was determined immediately post HBOT, nor at 6 months. Further, the beneficial effect after 1 year was sensitive to allocation of dropouts. Venous ulcer: (1 trial, 16 patients): This trial reported data at six weeks (wound size reduction) and 18 weeks (wound size reduction and healing rate) and suggested a significant benefit of HBOT in terms of reduction in ulcer area only at 6 weeks (WMD 33%, 95%CI 19% to 47%, P<0.00001). Arterial and pressure ulcers: No trials that satisfied inclusion criteria were located.

REVIEWERS' CONCLUSIONS

In people with foot ulcers due to diabetes, HBOT significantly reduced the risk of major amputation and may improve the chance of healing at 1 year. The application of HBOT to these patients may be justified where HBOT facilities are available, however economic evaluations should be undertaken. In view of the modest number of patients, methodological shortcomings and poor reporting, this result should be interpreted cautiously however, and an appropriately powered trial of high methodological rigour is justified to verify this finding and further define those patients who can be expected to derive most benefit from HBOT. Regarding the effect of HBOT on chronic wounds associated with other pathologies, any benefit from HBOT will need to be examined in further, rigorous randomised trials. The routine management of such wounds with HBOT is not justified by the evidence in this review.

[Clinical application--suture materials]

The surgical suture should be chosen in dependence of the tissue being operated upon and be oriented on the main properties of its chemical composition. Synthetic absorbable suture materials are the first choice in the majority of the procedures, to prevent the formation of foreign body reaction--excepting sites subjected to continuous mechanical stress, for example hernias, orthopedic and vascular surgery. By causing lesser tissue damage and interfilament bacterial transport, monofilament sutures are preferable than multifilament ones. However, knotting monofilament sutures requires additional skills in comparison to multifilament strains, due to their special handling an knotting properties.

[Pseudoaneurysm of the right gastric artery]

Mostly, the rare pseudoaneurysm of the right gastric artery is a complication of a pancreatitis. Clinical findings might be normal, but there is also a hemorrhagic shock in case of rupture. Diagnostic procedures are ultrasound, colour doppler ultrasound, computertomography and angiography for treatment. While endoscopy does not enable a therapeutic approach, interventional radiology with transcatheter embolization is a modality, which can be performed fast, sure and without complications. In case of an intractable acute hemorrhage the embolization is an alternative to surgical emergency.

Colour flow Doppler ultrasound of the carotid bifurcation: can it replace routine angiography before carotid endarterectomy?

The objective of this study was to assess the diagnostic accuracy of colour flow Doppler ultrasound (CFD) and its potential to replace digital subtraction angiography (DSA) before carotid endarterectomy (CEA). All patients undergoing CFD of the carotid bifurcation in our department over a period of 1-1/2 years for whom both CFD and DSA results were available were included in the study. We evaluated the feasibility of CFD, its diagnostic accuracy and its potential to diagnose clinically significant stenosis (50%, 70% and 90% NASCET type diameter stenosis) compared with DSA. 225 carotid bifurcations in 116 patients met the criteria for evaluation (biplane arterial DSA without superimposition). Data analysis yielded the following diagnostic performance of CFD: sensitivity for a 50% stenosis 91.4% (95% confidence interval (CI) 83.3--96.2%), specificity 93.2% (95% CI 87.1--96.8%) and accuracy 92.4% (95% CI 88.4--95.4%); sensitivity for a 70% stenosis 89.2% (95% CI 81.9--94.1%), specificity 96.2% (95% CI 90.5--98.6%) and accuracy 92.4% (95% CI 88.4--95.4%). In 9 of 116 cases, carotid angiography was used to evaluate inconclusive CFD results. DSA disclosed relevant information not suspected by CFD in only 1 of the 116 cases. Thus, 91% (106/116) of the angiographies could have been dispensed with without loss of information. One major stroke occurred during diagnostic DSA. We conclude that DSA of the carotid arteries is unnecessary when CFD is unequivocal. The diagnostic gain of DSA must be counterweighted against its potential risks.

[Restoration of blood circulation in reperfusion of ischemic tissues]

In experiment there were studied changes of the tissue blood circulation and microcirculation during postischemic reperfusion of skeletal muscles with various density of capillaries. It was established that reactive hyperemia, caused mainly by enhancement of extracapillary tissue blood flow. While persistence of durable arterial hypertension the capillaries quantity and potential volume of microcirculatory bed are reducing, negatively influencing the blood circulation restoration process during postischemic reperfusion. In chronic ischemia the potential volume of microcirculation is increasing, securing complete restoration of blood circulation in postischemic reperfusion.

Chemokines IL-8, GROalpha, MCP-1, IP-10, and Mig are sequentially and differentially expressed during phase-specific infiltration of leukocyte subsets in human wound healing

Healing of cutaneous wounds requires a complex integrated network of repair mechanisms, including the action of newly recruited leukocytes. Using a skin repair model in adult humans, we investigated the role chemokines play in sequential infiltration of leukocyte subsets during wound healing. At day 1 after injury, the C-X-C chemokines IL-8 and growth-related oncogene alpha are maximally expressed in the superficial wound bed and are spatially and temporally associated with neutrophil infiltration. IL-8 and growth-related oncogene alpha profiles also correlate with keratinocyte migration and subsequently subside after wound closure at day 4. Macrophage infiltration reaches the highest levels at day 2 and is paralleled by monocyte chemoattractant protein-1 mRNA expression in both the basal layer of the proliferative epidermis at the wound margins and mononuclear cells in the wound area. Other monocyte-attracting chemokines such as monocyte chemoattractant protein-3, macrophage inflammatory protein-1alpha and -1beta, RANTES, and 1309 are undetectable. At day 4, perivascular focal lymphocyte accumulation correlates with strong focal expression of the C-X-C chemokines Mig and IP-10. Our results suggest that a dynamic set of chemokines contributes to the spatially and temporally different infiltration of leukocyte subsets and thus integrates the inflammatory and reparative processes during wound repair.

[Coercive measures in psychiatry. Restraint on psychiatric units of the Hannover Medical University]

Following a short review of some studies from Germany and Switzerland on coercive measures in psychiatry a retrospective investigation of restraints in the two psychiatric departments of the Medical School of Hannover is presented. Frequency, time, diagnoses, reasons and procedures are reported in detail and discussed in comparison with results of other studies.

Low dimensional attractors in discharges of sensory neurons of the rat spinal dorsal horn are maintained by supraspinal descending systems

Background activity was recorded from sensory neurons in laminae I-V of the lumbar spinal dorsal horn of the rat prior to and during cold block spinalization at the cervical cord. To graphically and quantitatively describe the complexity of the discharge patterns, phase space portraits were plotted and the correlation dimension D2 was calculated by using the Grassberger-Procaccia algorithm adopted for point processes, i.e. for series of interspike intervals. The algorithm is validated both for the Baker transformation, which is a simple point process, and for the Lorenz model, whereby a transformation from continuous to point process variables is achieved. A method of surrogate data is provided in order to show the difference between original neuronal patterns and their surrogate stochastic data. Therefore, this method shows that neuronal discharge patterns cannot be fully described in terms of interspike interval histograms. However, in the intact cord most (73%) of the neurons displayed background activity with low (0.28-4.3) D2 values. During spinalization, D2 values significantly increased in 68% of the neurons showing previously low D2 values, irrespective of classification and laminar location of neurons, thus proving that tonic descending systems may maintain a high order in the discharge of sensory dorsal horn neurons.

Peritoneal seeding of gallbladder cancer after laparoscopic cholecystectomy

We report a case of peritoneal seeding of an unsuspected adenocarcinoma of the gallbladder following laparoscopic cholecystectomy despite the use of a retrieval bag. The metastasis developed at the umbilical trocar site, which was also used to extract the resected gallbladder. There was no evidence foe a leak of the retrieval bag. Most likely malignant cells became desquamated during the operation, implanting themselves in the tissue during the removal of the bag. Taking into consideration previous reports and the dismal prognosis of the disease, we discuss the management in the case of an incidental carcinoma.

Distribution of Nocturnal Forest Birds and Mammals in North-Eastern New South Wales: Relationships With Environmental Variables and Management History

A regional survey of the forests in north-eastern New South Wales recorded eight species of nocturnal forest birds and nine species of arboreal marsupials from 291 sites. Three major environmental gradients accounting for the distribution of these species in north-eastern New South Wales were identified: elevation, forest type (wet forest types having a dense mesic understorey or dry forest types having an open or sparse understorey), and logging intensity. Characteristic assemblages of species were associated with each end of these three gradients. A core group of species occurred across a wide range of environmental conditions, including logged and unlogged forest. Most species occurred with similar frequency in logged and unlogged forest. Implications for forest management are discussed.

Human monoclonal antibodies from stomach carcinoma patients react with Helicobacter pylori and stimulate stomach cancer cells in vitro

BACKGROUND

In recent studies, an increased incidence of gastric adenocarcinomas was observed in patients with Helicobacter pylori infection. However, the extent to which this coincidence is caused by immunologic mechanisms is unknown.

METHODS

Two human monoclonal antibodies (MoAbs) from patients with stomach carcinoma and H. pylori-associated gastritis were isolated and established by fusion of spleen cells with the heteromyeloma HAB-1. The reactivity of these human MoAbs was investigated in functional adhesion assays and on Western blots of tissue, tumor cell, and bacterial extracts. Their stimulation and proliferation were tested by the MTT test and 3-H-thymidine incorporation tests.

RESULTS

The two monoclonal immunoglobulin-M antibodies, 103/51 and 105/79, inhibited adhesion of tumor cells. On bacterial extracts antibody 103/51 identified protein bands of 55 kilodaltons (kd) and 80 kd, and in tumor cell extracts, a specific protein of approximately about 110 kd and 140 kd. Antibody 105/79 identified a 55 kd protein in bacterial extracts and a 110 kd protein in tumor extracts. In addition, in the 3-H-thymidine incorporation and MTT assay the antibodies showed a stimulatory and growth-enhancing effect on tumor cells in vitro. A similar activity was observed in sera from patients with gastric carcinoma, indicating a physiologic role of such antibodies in vivo.

CONCLUSION

The human monoclonal antibodies described here react with H. pylori and cross-react with and stimulate gastric carcinoma cells. It is possible that the production of these antibodies is primarily stimulated by bacterial antigens which cause chronic gastritis and that they might be indirectly responsible for the recently described higher incidence of gastric cancer because of the simultaneous reaction and stimulation of tumor cells they cause.

[Duration of wound healing and tissue resistance as important criteria for selecting suture materials in colon surgery]

The modern absorbable suture materials are well introduced in colonic surgery. Surgeon's intension is to reduce foreign body reactions by using small sized sutures and will be limited by the suture holding capacity of the tissue. Suture holding capacity of the human colon is about 9 +/- 2 N. Wound healing of colon anastomoses normally lasts 10 to 12 days. The braided absorbable suture materials Dexon, Dexon plus and Vicryl (size 3-0 USP) have a knot breaking strength of about 10 N after 12 days implantation in the human colon, the monofilament absorbable sutures PDS and Maxon have about 20 N resting strength after implantation. These results document that the size 3-0 USP (2-metric) should be the lowest limit for the braided absorbable suture materials used in colonic surgery.