Observing Etna volcano dynamics through seismic and deformation patterns

Geophysical data provide the chance to investigate a volcano's dynamics; considerable information can especially be gleaned on the stress and strain patterns accompanying the internal processes and the effect of magma ascent on the main structures triggering earthquakes. Here, we analysed in detail the seismicity recorded over the last two decades on Etna volcano (southern Italy), focusing on earthquakes distribution and focal mechanism clustering; the ground deformation pattern affecting the volcanic edifice with the inflation and deflation phases was also examined. Analysed data were compared in order to shed light on possible relationships with the volcanic activity and to better understand the internal dynamics of the volcano over time. Significant steps during or shortly before major eruptions in the seismic strain release and ground deformation temporal series highlight a straightforward relationship between seismicity occurring at shallow level, inflation/deflation and volcanism. Furthermore, at depths greater than 5-7 km, down to about 20 km, the orientation of the P- and T-axes clearly indicate the existence of a pressure source in the central part of the volcano. All the results underline that the stress field related to the volcano plumbing system interferes with the regional field, partly overriding it.

Long-term effects of an intensive prevention program (IPP) after acute myocardial infarction – the IPP Follow-up and Prevention Boost Trial

Background

The effects of an intensive prevention program (IPP) for 12 months following 3-week rehabilitation after myocardial infarction (MI) have been proven by the randomized IPP trial. The present study investigates if the effects of IPP persist one year after termination of the program and if a reintervention after >24 months (“prevention boost”) is effective.

Methods

In the IPP trial patients were recruited during hospitalization for acute MI and randomly assigned to IPP versus usual care (UC) one month after discharge (after 3-week rehabilitation). IPP was coordinated by non-physician prevention assistants and included intensive group education sessions, telephone calls, telemetric and clinical control of risk factors. Primary study endpoint was the IPP Prevention Score, a sum score evaluating six major risk factors. The score ranges from 0 to 15 points, with a score of 15 points indicating best risk factor control.

In the present study the effects of IPP were investigated after 24 months – one year after termination of the program. Thereafter, patients of the IPP study arm with at least one insufficiently controlled risk factor were randomly assigned to a 2-months reintervention (“prevention boost”) vs. no reintervention.

Results

At long-term follow-up after 24 months, 129 patients of the IPP study arm were compared to 136 patients of the UC study arm. IPP was associated with a significantly better risk factor control compared to UC at 24 months (IPP Prevention Score 10.9±2.3 points in the IPP group vs. 9.4±2.3 points in the UC group, p<0.01). However, in the IPP group a decrease of risk factor control was observed at the 24-months visit compared to the 12-months visit at the end of the prevention program (IPP Prevention Score 10.9±2.3 points at 24 months vs. 11.6±2.2 points at 12 months, p<0.05, Figure 1).

A 2-months reintervention (“prevention boost”) was effective to improve risk factor control during long-term course: IPP Prevention Score increased from 10.5±2.1 points to 10.7±1.9 points in the reintervention group, while it decreased from 10.5±2.1 points to 9.7±2.1 points in the group without reintervention (p<0.05 between the groups, Figure 1).

Conclusions

IPP was associated with a better risk factor control compared to UC during 24 months; however, a deterioration of risk factors after termination of IPP suggests that even a 12-months prevention program is not long enough. The effects of a short reintervention after >24 months (“prevention boost”) indicate the need for prevention concepts that are based on repetitive personal contacts during long-term course after coronary events.

Figure 1

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Stiftung Bremer Herzen (Bremen Heart Foundation)

Development of 1- and 5-year outcomes between 2006 and 2018 in patients with uncomplicated ST-elevation myocardial infarctions and successful percutaneous coronary intervention

Introduction

While modern P2Y12-inhibitors and drug eluting stents (DES) have changed therapeutic options in patients with ST-elevation mycoardial infarctions (STEMI) during the last decade, there is few data on their impact in real world registries. Aim of the present study was to analyze changes in mortality and major adverse cardiac and cererobrovascular event rates (MACCE: death, reinfarction,stroke) during the last 13 years in patients with uncomplicated STEMI after successful percutaneous coronary intervention (PCI).

Methods

All consecutive STEMI-patients, admitted between 2006 and 2018 and successfully treated with PCI (TIMI flow ≥2) in a large German heart center entered analysis. To reduce confounding pts. with STEMI complicated by heart failure and pts. >70 yrs. of age were excluded.

Results

A STEMI-cohort of 5016 pts. was analysed, with a mean age of 55.9±8 yrs., 19% females, 16% diabetics and 59% smokers. At the beginning of the study period (2006) no patient was treated with ticagrelor/prasugrel and only 5% had a DES implanted. In 2018 92% were treated with prasugrel or ticagrelor and 96% with a DES. The reduction in 1-year-mortality during the study period was not significant: 2006–11: 3.4%, 2012–19: 3.1%, p=0.4, however the reduction in 1-year-MACCE was: 2006–11: 8.3%, 2012–18: 5.7%, p<0.01. This could mainly be attributed to a reduction in reinfarctions: 2006–11: 4.9%, 2012–18: 2.8%, p<0.01. Subgroup analysis revealed that with the exception of diabetics all subgroups showed a significant decline in MACCE-rates during the study period. It was more pronounced in women, non-smokers and patients with a high socioeconomic status (SES) (Table). Analysis of 5-year-data revealed a significant reduction in both 5-year-mortality (2006–09: 9.1%, 2010–13: 6.8%, p<0.01) and 5-year-MACCE-rates: 2006–09: 19.3%, 2010–13: 14.5%, p<0.01.

Conclusions

This analysis of registry data over a study period of 13 years reveals, that for patients with uncomplicated STEMI and successful PCI a significantly better 1- and 5-year-outcome could be achieved during the last years. This improvement of prognosis was more pronounced in specific subgroups, such as women, non-diabetics and patients with higher SES.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Stiftung Bremer Herzen, Gesundheit Nord

Impact of morphine treatment with and without metoclopramide co-administration on myocardial and microvascular injury in acute myocardial infarction: insights from a randomized trial

Background

Intravenous morphine administration in patients with acute myocardial infarction (AMI) can adversely affect platelet inhibition induced by P2Y12 receptor antagonists, potentially resulting in an increased risk of adverse clinical events. In contrast, some evidence suggests that opioid agonists may have cardioprotective effects on the myocardium. Currently available data in this regard are, however, sparse, inconsistent, and methodologically limited.

Purpose

The aim of this study was to investigate the impact of morphine with or without metoclopramide (MCP) co-administration on myocardial and microvascular injury after AMI assessed by cardiac magnetic resonance (CMR).

Methods

This prospective, randomized, single-center study assigned 138 patients with AMI in a 1:1:1 ratio to (a) ticagrelor 180 mg plus intravenous morphine 5 mg (morphine group); (b) ticagrelor 180 mg plus intravenous morphine 5 mg and MCP 10 mg (morphine + MCP group); or (c) ticagrelor 180 mg plus intravenous placebo (control group). Study drugs were administered before primary percutaneous coronary intervention. CMR was performed in 101 patients on day 1–4 after the index event to assess infarct size, microvascular obstruction, and left ventricular ejection fraction.

Results

Infarct size was significantly smaller in the morphine only group as compared to controls (15.5%LV [IQR 5.0 to 21.4%LV] vs. 17.9%LV [IQR 12.3 to 32.9%LV]; p=0.047). Furthermore, the number of patients with microvascular obstruction was significantly lower after morphine administration (10/36 [28%] versus 21/39 [54%]; p=0.022) and the extent of microvascular obstruction was smaller (0%LV [0 to 1.40%LV] versus 0.74%LV [0 to 3.10%LV]; p=0.037). In multivariable regression analysis, morphine administration was independently associated with a reduced risk for the occurrence of microvascular obstruction (odds ratio 0.37; 95% confidence interval 0.14 to 0.93; p=0.035). Left ventricular ejection fraction did not differ significantly between the morphine and the control group (p=0.970) and there was no significant difference in left ventricular ejection fraction (p=0.790), infarct size (p=0.491), and extent (p=0.753) or presence (p=0.914) of microvascular obstruction when comparing the morphine + MCP group to the control group.

Conclusions

In this randomized study, intravenous administration of morphine prior to primary percutaneous coronary intervention resulted in a significant reduction of myocardial and microvascular damage following AMI. This potential cardioprotective effect of morphine requires further evaluation in well-designed future trials with clinical endpoints.

Funding Acknowledgement

Type of funding source: None

P1438Predictors and clinical impact of bleeding events after left atrial appendage closure in patients with high risk or a history of bleeding

Background

Left atrial appendage closure (LAAC) has emerged as an alternative to oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation and may be especially attractive in patients with high risk or a history of bleeding. However, data of clinical benefit and incidence of post-procedural bleeding in patients with both high risk of bleeding and ischemic cerebral stroke after LAAC are lacking.

Objectives

This study sought to identify predictors and the prognostic impact of post-LAAC bleeding in patients at high risk and/or history of bleeding in the direct oral anticoagulant therapy (DOAC) era.

Methods and results

We retrospectively enrolled a total of 195 patients (75 ± 8.7 years, 38% female, 47% with previous major bleeding, mean CHA2DS2-VASc score 4.3 ± 1.6 and mean HAS-BLED score 2.7 ± 1.1) undergoing endocardial (91%) or epicardial (9%) LAAC during a mean follow-up of 339 ± 319 days. Twenty-three (11.9%) patients developed procedure-unrelated bleeding events after a median of 147 (43, 362) days after LAAC, in 12/23 (52%) patients under single antiplatelet therapy (SAPT), 6/23 (26%) dual antiplatelet therapy (DAPT), 1/23 (4%)  DOAC, 1/23 (4%) VKA, 2/23 (9%) dual therapy (SAPT and DOAC/VKA) and 1/23 (4%) triple therapy (DAPT and DOAC/VKA). (Figure) Diabetes mellitus and previous major bleeding were identified as the independent predictors of post-LAAC bleeding (Odds ratio 2.65 [95% CI:1.04-6.73], p = 0.041, and 5.50 [95% confidence interval:1.72-17.5], p = 0.004). Post-LAAC bleeding was associated with all-cause death (9/23 [39%] vs 18/171 [11%], p = 0.001), but not ischemic stroke/TIA (1/23 [4%] vs 6/171 [4%], p = 0.593) nor device thrombus (2/23 [9%] vs 3/171 [2%], p = 0.108). Kaplan-Meier curve estimated that patients with post-LAAC bleeding had a worse mortality than those without post-LAAC bleeding (3-year mortality; 35.6% [95%CI; 11.6-61.0%] vs 68.7% [45.0-83.8], p = 0.029)

Conclusions

In AF patients with high bleeding risk or history of bleeding undergoing LAAC, bleeding events are common and may occur even after long-term duration after LAAC. Previous major bleeding history strongly predicts subsequent bleeding events following LAAC and is associated with unfavorable mortality. Further investigations are required to identify optimal post-procedural antithrombotic strategies for patients undergoing LAAC with previous major bleeding.

Abstract Figure. The association between time to bleeding

Die Rolle der Thrombozyten in der Pathophysiologie des akuten Koronarsyndroms

Kardiovaskuläre Erkrankungen, besonders die koronare Herzkrankheit, stellen derzeit die häufigste Todesursache in der westlichen Welt dar und repräsentieren eine zentrale Herausforderung für moderne Wissenschaft und Medizin. Die Pathophysiologie der koronaren Herzkrankheit basiert im Wesentlichen auf der Entstehung und dem biologischen Remodelling atherosklerotischer Plaques. Vor allem in fortgeschrittenen Stadien, aber auch in der frühen Phase der Atherosklerose, kommt es zur Ruptur atherosklerotischer Plaques, die zur klinischen Manifestation des akuten Koronarsyndroms in Form instabiler Angina pectoris, nicht transmuralen oder transmuralen Myokardinfarkts führen kann. Neben inflammatorischen Zellen wie Monozyten, spielen Thrombozyten eine essenzielle Rolle in der frühen wie auch der späten Phase atherosklerotischer Erkrankungen.

Diese Übersicht fasst die grundlegenden pathophysiologischen Mechanismen der Plättchenadhäsion und -sekretion, die molekularen Schritte, die in die plättchenvermittelte Thrombusentstehung im Bereich atherosklerotischer Läsionen eingreifen und die Bedeutung der Thrombozytenakkumulation im reperfundierten Myokard zusammen.

Use of COALDATA to help retrieve and estimate the physical properties of coals, coal liquids and coal chemicals

COALDATA, a factual databank of the properties of coal samples, coal liquids (distillation cuts from coal liquefaction products) and coal chemicals (pure chemical compounds con tained in the coal liquids) was developed. It contains data on:

(i) physical properties of coals, such as calonfic values, ash content, ash properties, maceral analyses, ultimate analyses.

(ii) thermophysical properties of coal liquids and coal chem icals, e.g. vapour pressures, vapour-liquid-equilibrium data, heat capacities, transport properties, surface ten sions, densities.

The databank is managed by DECHEMA's Data Retrieval System DEDARS, which stores numerical data as well as non-numerical data, such as bibliographic information. Data and substances are labelled by "tags" which characterize the kind of stored data and substances. All the information is organized in the form of documents. Each document refers, for example, to a scientific paper or book and is composed of a bibliographic part, a list of descriptors, an abstract, a compo nent description, numerical values and their units.

Besides literature data COALDATA contains recom mended property values. These are stored as regression coeffi cients and with the help of implemented correlation methods it is possible to calculate the properties.

Platelet surface expression of stromal cell-derived factor-1 receptors CXCR4 and CXCR7 is associated with clinical outcomes in patients with coronary artery disease

BACKGROUND

Surface expression of stromal cell-derived factor-1 (SDF-1, CXCL12) on platelets is enhanced during ischemic events and plays an important role in peripheral homing of stem cells and myocardial repair mechanisms. SDF-1 effects are mediated through CXCR4 and CXCR7. Both CXCR4 and CXCR7 are surface expressed on human platelets and to a higher degree in patients with coronary artery disease (CAD) compared with healthy controls. In this study, we investigated the prognostic role of platelet CXCR4- and CXCR7 surface expression in patients with symptomatic CAD.

METHODS AND RESULTS

In a cohort study, platelet surface expression of CXCR4 and CXCR7 was measured by using flow cytometry in 284 patients with symptomatic CAD at the time of percutaneous coronary intervention (PCI). The primary combined end point was defined as all-cause death and/or myocardial infarction (MI) during 12-month follow-up. Secondary end points were defined as the single events of all-cause death and MI. We found significant differences of CXCR4 values in patients who developed a combined end point compared with event-free patients (mean MFIAUTHOR: Please define MFI at first use. 3.17 vs. 3.44, 95% confidence interval [CI] 0.09-0.45) and in patients who subsequently died (mean MFI 3.10 vs. 3.42, 95% CI 0.09-0.56). In multivariate Cox regression analysis, lower platelet CXCR4 levels were independently and significantly associated with all-cause mortality (hazard ratio 0.24, 95% CI 0.07-0.87) and the primary combined end point of all-cause death and/or MI (hazard ratio 0.30, 95% CI 0.13-0.72).

CONCLUSION

These findings highlight a potential prognostic value of platelet expression CXCR4 on clinical outcomes in patients with CAD.

Zur Frage der Funktion des braunen Fettgewebes bei winterschlafenden Säugetieren

Im Anschluß an Untersuchungen des braunen Fettgewebes von Hamster und Ratte (SCHIERER) werden die Versuche von ZIRM unter der Voraussetzung einer Speicherfunktion des Gewebes betrachtet. Es zeigt sich, daß die dargestellten Ergebnisse nicht zu der Annahme berechtigen, daß es sich beim braunen Fettgewebe (der „Winterschlafdrüse“) um ein Inkretorgan handelt. Vielmehr lassen sich die Befunde von ZIRM auch mit der Vorstellung der Funktion eines Speicherorgans hinreichend erklären.

Implications of glycoprotein VI for theranostics

Glycoprotein VI (GPVI), a membrane glycoprotein solely expressed in platelets and megakaryocytes, plays a critical role in thrombus formation due to collagen/GPVI-mediated platelet activation and adhesion. Recent studies have shown that surface expression of GPVI on circulating platelets is enhanced in acute cardiovascular diseases such as myocardial infarction and ischaemic stroke. Increased GPVI levels are associated with poor clinical outcome and are an early indicator for imminent myocardial infarction in patients with chest pain. The soluble form of the dimeric GPVI fusion protein (sGPVI-Fc) binds with high affinity to collagen and atherosclerotic plaque tissue. Non-invasive imaging studies with radiolabelled sGPVI-Fc show specific binding activity to vascular lesions in vivo. Further, sGPVI-Fc has been developed as a new therapeutic platelet-based strategy for lesion-directed antithrombotic therapy. This review summarises the potential of GPVI for diagnostic and therapeutic options based on novel non-invasive molecular imaging modalities to ameliorate care of patients with cardiovascular diseases.

Reliability issues for a bolometer detector for ITER at high operating temperatures

The first detector prototypes for the ITER bolometer diagnostic featuring a 12.5 μm thick Pt-absorber have been realized and characterized in laboratory tests. The results show linear dependencies of the calibration parameters and are in line with measurements of prototypes with thinner absorbers. However, thermal cycling tests up to 450 °C of the prototypes with thick absorbers demonstrated that their reliability at these elevated operating temperatures is not yet sufficient. Profilometer measurements showed a deflection of the membrane hinting to stresses due to the deposition processes of the absorber. Finite element analysis (FEA) managed to reproduce the deflection and identified the highest stresses in the membrane in the region around the corners of the absorber. FEA was further used to identify changes in the geometry of the absorber with a positive impact on the intrinsic stresses of the membrane. However, further improvements are still necessary.

Bioremediation of soil contaminated with pentachlorophenol by Anthracophyllum discolor and its effect on soil microbial community

Bioaugmentation is a promising technology to clean up sites contaminated with recalcitrant chemicals. White-rot fungi have proven to be effective in the degradation of pentachlorophenol. Here, we report the bioremediation of soil contaminated with pentachlorophenol (PCP) by Anthracophyllum discolor and its impact on the soil microbial community. In this study three types of microcosms were established: fresh soil (C(0)), fresh soil plus wheat straw (WS(0)) and, fresh soil plus wheat straw inoculated with A. discolor (WSAD(0)). Additionally, similar treatments and a control of sterile soil spiked with PCP (C(250), WS(250) and WSAD(250)) were used to evaluate the remediation and adsorption of PCP. The PCP removal, total microbial activity, and enzymatic activities were evaluated. This study also investigated the structure of soil microbial community by denaturing gradient gel electrophoresis (DGGE), identifying some of the dominant bacterial and fungal species. The results showed that PCP was effectively degraded in soils by A. discolor and by indigenous soil microorganisms. The addition of wheat straw increased the PCP degradation and enzymatic activities. Only laccase activity was negatively affected by PCP contamination. The PCP degradation was associated with changes in microbial communities, mainly stimulation of members of bacterial phylum Proteobacteria (Xanthomonadaceae, Burkholderiaceae and Enterobacteriaceae), and fungal phylum Ascomycota and Basidiomycota. This study shows the ability of A. discolor to degrade PCP from contaminated soil, and demonstrates that agricultural residues, such as wheat straw, can be used as growth substrate by microorganisms in PCP-contaminated soil, demonstrating a great potential of autochthonous microorganisms for soil remediation.

Residual platelet activity is increased in clopidogrel- and ASA-treated patients with coronary stenting for acute coronary syndromes compared with stable coronary artery disease

OBJECTIVE

To evaluate residual platelet activity in a consecutive cohort of patients treated with dual antiplatelet therapy after coronary stent implantation

DESIGN

Prospective single-centre cohort study.

SETTING

University hospital in Germany.

PATIENTS

480 patients with symptomatic coronary artery disease (n = 221 (46%) or acute coronary syndrome (ACS; n = 259 (54%) stable angina) were studied. Platelet activity was measured by collagen- (5 microg/ml) and adenosine diphosphate- (ADP; 20 micromol/l) induced platelet aggregation to assess post-treatment activity in patients treated with acetylsalicylic acid (500 mg bolus intravenously followed by 100 mg once a day) and clopidogrel (600 mg loading dose followed by 75 mg once a day)

MAIN OUTCOME MEASURES

Increased residual platelet activity (IRPA) was defined if platelet aggregation was in the upper tertile of values in the patient collective. Association of epidemiological factors with IRPA was evaluated in a multivariate logistic regression analysis.

RESULTS

IRPA-ADP was found in 53 patients (11.0%) and IRPA-collagen in 42 patients (8.8%). ACS was associated with IRPA independently from other factors (for IRPA-collagen: odds ratio (OR) = 2.3, 95% confidence interval (CI) 1.2 to 4.5, p<0.05; for IRPA-ADP: OR = 2.4; 95% CI 1.3 to 4.4, p<0.01; for IRPA-ADP/collagen: OR = 4.5, 95% CI 1.2 to 16.9, p<0.05).

CONCLUSIONS

The data suggest that ACS is independently associated with IRPA despite conventional antiplatelet therapy. Further studies are warranted to demonstrate the effects of intensified antiplatelet therapy for patients with acute coronary events.

Animal serum-free culture conditions for isolation and expansion of multipotent mesenchymal stromal cells from human BM

BACKGROUND

Multipotent mesenchymal stromal cells (MSC) have become important tools in regenerative and transplantation medicine. Rapidly increasing numbers of patients are receiving in vitro-expanded MSC. Culture conditions typically include FSC because human serum does not fully support growth of human MSC in vitro (MSC(FCS)). Concerns regarding BSE, other infectious complications and host immune reactions have fueled investigation of alternative culture supplements.

METHODS

As PDGF has long been identified as a growth factor for MSC, we tested media supplementation with platelet lysate for support of MSC proliferation.

RESULTS

We found that primary cultures of BM-derived MSC can be established with animal serum-free media containing fresh frozen plasma and platelets (MSC(FFPP)). Moreover, MSC(FFPP) showed vigorous proliferation that was superior to classical culture conditions containing FCS. MSC(FFPP) morphology was equivalent to MSC(FCS), and MSC(FFPP) expressed CD73, CD90, CD105, CD106, CD146 and HLA-ABC while being negative for CD34, CD45 and surface HLA-DR, as expected. In addition to being phenotypically identical, MSC(FFPP) could efficiently differentiate into adipocytes and osteoblasts. In terms of immune regulatory properties, MSC(FFPP) were indistinguishable from MSC(FCS). Proliferation of PBMC induced by IL-2 in combination with OKT-3 or by PHA was inhibited in the presence of MSC(FFPP).

DISCUSSION

Taken together, FCS can be replaced safely by FFPP in cultures of MSC for clinical purposes.

[Recurrent transient ischaemic attacks in a patient with pansinusitis]

A 31-year-old woman presented with neurological deficits after an operation for sinusitis. The cranial MRI revealed multiple ischaemic lesions. Laboratory results showed a hypereosinophilia as well as elevated creatine kinase and troponin levels. The ECG implied ST elevations, the left ventricular ejection fraction was highly reduced and the cardiac MRI was suspicious for endomyocarditis. The cardiac biopsy demonstrated the findings of Loeffler's endocarditis. In conclusion the diagnosis of hypereosinophilic syndrome was made and identified as the cause of the neurological deficits.

[The role of platelets for the pathophysiology of acute coronary syndromes]

Cardiovascular diseases, especially ischaemic heart disease, are actually the most frequent causes of death in the Western world and represent a central challenge for modern research and medicine. The pathophysiology of ischaemic heart disease is based upon the development and biological remodelling of atherosclerotic plaques. Mainly at late stages, but also in the early phase of atherosclerosis, rupture of the atherosclerotic plaque occurs and may lead to the clinical manifestation of acute coronary syndromes, including unstable angina pectoris, non-transmural or transmural myocardial infarction. Next to inflammation mediating cells like monocytes, platelets play an essential role at early and late stages of atherosclerotic disorders. This review summarizes the basic pathophysiological mechanism of platelet adhesion and secretion, the molecular steps involved in platelet mediated thrombus formation in the atherosclerotic microenvironment and the role of platelet accumulation in reperfused myocardium.

Effect of low molecular weight heparin on intra-abdominal metastasis in a laparoscopic experimental study

BACKGROUND AND AIMS

Metastatization, adhesion, invasion, and growth of tumor cells involve a cascade of complex phenomena which may be affected. We investigated the effect of a low molecular weight heparin, reviparin, on intra-abdominal tumor growth and intra-abdominal metastasis in rats undergoing laparoscopy.

METHODS

CC531 adenocarcinoma cells (5x10(6) cells/ml) were administered intraperitoneally to 150 Wistar Albino Glaxo rats, with 15 groups of animals each. During laparoscopy 1 ml saline containing 0.0, 0.5, 2.0,; 4.0, and 10 mg reviparin/kg b.w. was introduced intraperitoneally (i.p.), daily subcutaneously (s.c.), or combined. After 21 days the animals were killed and underwent autopsy, and the tumor weight and the number of metastases on the liver surface were determined.

RESULTS

Tumor weight was significantly reduced by 4.0 and 10.0 mg/kg b.w. but not by 0.5 or 2.0 mg/kg b.w. compared to controls. Decreased metastatization was observed in all treated groups. These effects were most pronounced after the s.c. or combined i.p. and s.c. administration, whereas after a sole i.p. administration only the highest dose of 10 mg/kg b.w. induced a significant inhibition of tumor growth.

CONCLUSION

Low molecular weight heparin given s.c. or in combination of i.p. lavage and s.c. injections significantly inhibits intra-abdominal tumor growth and intraperitoneal metastasis of CC531 adenocarcinoma cells in rats undergoing laparoscopy. This may offer additional therapeutic options for patients undergoing laparoscopic and also open cancer surgery.

[Treatment of a subcapsular renal bleeding after extracorporeal shockwave lithotripsy with recombinant, activated factor VII]

We report on a patient who suffered a large subcapsular and perirenal haematoma after extracorporeal shockwave lithotripsy. Despite surgical intervention the bleeding did not stop for 6 days and 10 units of packed red blood cells were transfused. With the treatment of recombinant, activated factor VIII (NovoSeven((R))) an immediate haemostasis could be reached, so that impending nephrectomy could be avoided. This is the first case where FVIIa has been successfully used to stop a trauma-related bleeding in a patient without any obvious accompanying coagulation disorder.

[Detection of cerebral embolism using transcranial Doppler sonography: can artifacts be reliably recognized?]

A requirement for the use of TCD for the detection of emboli in the field of cardiac and vascular surgery is the reliable differentiation between true emboli and artifacts. In ten healthy volunteers we carried out a study to establish the method with which artefacts can most reliably be identified. Automatic detection of increasing signal intensity misinterpreted 14% of all artifacts as emboli; 1.7% of all artifacts sounded suspicious for embolism, and 0.6% met the classical criteria of an embolus. Using simultaneous recording of the flow signal in two sections of the middle cerebral artery, all artifacts were identified on the basis of their simultaneous manifestation. Reliable intra-operative differentiation of emboli from artifacts requires attentive, continuous acoustic and visual analysis of signals by an experienced investigator familiar with the surgical procedure. The introduction of a multiple-depth algorithm might significantly improve the automatic detection program.

Cytotoxicity of dental alloy extracts and corresponding metal salt solutions

Adverse tissue reactions of the gingiva and the periodontium close to dental cast alloys may be caused by the effects of released metal elements. Tissue reactions depend upon the amounts of elements available which are a function of corrosion rates. Since pH values of standard corrosion solutions are as low as 2.3, such extracts are a priori not biocompatible. In the present study, elements released from dental cast alloys into cell-culture media were determined, and the cytotoxicity of these medium extracts was compared with the effectiveness of metal salt solutions prepared according to the metal elements found in extracts. The elements Ag, Cu, Ni, and Zn were detected in extracts of dental alloys and copper (positive control) by inductively coupled plasma atomic emission spectrometry (ICP-AES). Medium extracts of dental alloys were non-toxic in mouse fibroblasts (L929 cells). However, the amounts of elements found in these extracts were weakly cytotoxic when tested as salt solutions prepared from chloride (Cu2+, Zn2+, Ni2+) or sulfate (Ag1+) salts. When the test specimens were heat-treated before extraction, extracts were clearly cytotoxic in a dose-related manner. Again, the amounts of elements that caused 50% cell death (TC50) were slightly lower in corresponding salt solutions than in extracts. In general, cytotoxicity of medium extracts consistently proved to be slightly less than that of the corresponding salt solutions, probably due to the limitations of the chemical analysis of extracts. This should be taken into account if salt solutions are used instead of the medium extract.

Comparison of near-infrared spectroscopy and somatosensory evoked potentials for the detection of cerebral ischemia during carotid endarterectomy

BACKGROUND AND PURPOSE

We sought to assess the clinical value of regional cerebral saturation (rSO2) obtained by means of the cerebral oximeter INVOS 3100A (Somanetics) in comparison to monitoring of somatosensory evoked potentials (SEP) for the reliable detection of severe cerebral ischemia requiring shunt placement in the individual patient undergoing carotid surgery under general anesthesia.

METHODS

In 317 patients undergoing reconstructive surgery on the internal carotid artery, simultaneous recordings of SEP and rSO2 were obtained throughout the operation.

RESULTS

All 287 patients with preserved cortical SEP remained neurologically intact. Shunt placement was performed in 27 patients (9%) after flattening of cortical SEP during cross-clamping of the internal carotid artery. A stable rSO2 value just before cross-clamping and the lowest value after cross-clamping were registered, and the decrease was calculated. A statistically significant (P<0.01) decrease of rSO2 after cross-clamping could be found in patients without (64.9+/-8.3% to 60.9+/-9.9%) as well as in patients with consecutive loss of cortical SEP (65.8+/-9.1% to 56.1+/-13.4%). The difference of the decrease of rSO2 in both groups was highly significant (6.9+/-9.0% versus 15.6+/-14.0%; P<0.001). However, substantial interindividual variability of rSO2 and derived change of rSO2 did not allow the definition of a threshold value indicating need of shunt placement.

CONCLUSIONS

The reliability of SEP for the detection of clamp-related hypoperfusion has been reaffirmed. As long as rSO2 threshold values indicating critical cerebral ischemia are not defined, therapeutic interventions based on monitoring with the cerebral oximeter INVOS 3100A are not justified.

[Evaluation of the direct cost of trochanteric fractures in the elderly]

PURPOSE OF THE STUDY

The cost effectiveness of trochanteric hip fractures in 1995 at Pitié-Salpétrière Hospital in Paris has been thoroughly analysed. The aim of this retrospective study was to identify the factors responsible for the variation in the treatment cost of those fractures.

MATERIAL AND METHODS

Cost, Hospital stay, functional status, ASA score, mental status and surgical treatment were analysed in 74 patients aged over 60 years old.

RESULTS

The mean cost per patient was 23,901 FF divided as follows: 8.5 per cent for preoperative care, 40.5 per cent for surgical procedures, 51 per cent for post-operative care. The mean hospital stay was 18 days. The cost of hospital personnel (44 per cent) and medical materiel (26 per cent) were the two main sources of hospital expenses beside medical investigations (11 per cent), hostelry (8 per cent), blood transfusion (6 per cent) and drugs (5 per cent).

DISCUSSION

The duration of hospital stay was the only factor that affected statistically the mean cost per patient. Furthermore, factors related to the patient as age, sex, place of residence prior to admission, functional status, ASA score, mental status, had no influence on cost variation.

CONCLUSION

Therefore, the best way to reduce the cost of trochanteric fractures treatment is to develop convalescence structures to avoid a lengthy and costly hospital stay and to minimize the abuse utilization of medical materials.

Pharmacokinetic-pharmacodynamic modeling of the new steroid hypnotic eltanolone in healthy volunteers

BACKGROUND

In the last 4 y, several authors have reported largely satisfactory results using the new steroid intravenous anesthetic eltanolone (pregnanolone) to induce anesthesia. Until now, however, no investigations have addressed the infusion pharmacokinetics of eltanolone or used electroencephalographic effect data for full pharmacodynamic modeling. Thus the authors conducted a study to evaluate the pharmacokinetic and pharmacodynamic properties of eltanolone after infusion in healthy volunteers.

METHODS

Eltanolone emulsion was administered to 12 healthy men using a computer-controlled infusion device. Linearly increasing serum concentrations were generated for two consecutive infusions with an anticipated slope of 0.075 microgram.ml-1.min-1 and a targeted concentration of 2-2.5 micrograms/ml. During and after the infusion, electroencephalographic data were recorded as a continuous pharmacodynamic parameter to measure the hypnotic effect. In addition, blood pressure, heart rate, pulse oximetry, clinical signs of anesthesia, and any undesirable effects were recorded. The appearance of burst suppression periods in the raw electroencephalographic wave form was used as an end point for the infusion. Arterial blood samples were drawn frequently until 720 min after the cessation of the last infusion cycle. Eltanolone serum concentrations were measured using a specific gas chromatography-mass spectrometry assay. Nonlinear regression analysis was used to relate a power spectral parameter of the electroencephalograph (median frequency) to the serum concentration using a sigmoid Emax model, including an effect compartment to minimize possible hysteresis. Population pharmacokinetics were analyzed using an open three-compartment model.

RESULTS

The pharmacokinetic model parameters of eltanolone were characterized by a high total clearance (1.75 +/- 0.22 l/min), small volumes of distribution (Vc = 7.65 +/- 3.40 l; Vdss = 91.6 +/- 22 l), and relatively short half-lives (t1/2 alpha = 1.5 +/- 0.6 min; t1/2 beta = 27 +/- 5 min; t1/2 gamma = 184 +/- 32 min). With regard to the pharmacodynamic model parameters, eltanolone proved to be a potent hypnotic agent (Cp50 = 0.46 +/- 0.09 microgram/ml). The hypnotic effect coincided with a remarkable hysteresis between serum concentration and biophase, determined by an equilibration half-life of 8 min (ke0 = 0.087 +/- 0.013 min-1). All volunteers breathed spontaneously during the entire observation period and showed no clinically relevant hemodynamic changes. One volunteer experienced a convulsion while awakening.

CONCLUSIONS

Eltanolone is a new potent steroid-type hypnotic agent with rapid elimination characteristics. Although it is short-acting, the remarkable hysteresis limits the control and might complicate administration of eltanolone if it is used as a component of a complete intravenous anesthesia regimen. Furthermore, it involves the potential disadvantage of drug accumulation and it prolongs recovery if larger-than-necessary doses are used to induce anesthesia rapidly.

Lumbar strengthening in chronic low back pain patients. Physiologic and psychological benefits

The effects of exercise for isolated lumbar extensor muscles were examined in 54 chronic low-back pain patients. Subjects were randomly assigned to a 10-week exercise program (N = 31) or a wait-list control group (N = 23). Results indicated a significant increase in isometric lumbar extension strength for the treatment group and a significant reduction in reported pain compared with the control group (P 0.05). Treated subjects reported less physical and psychosocial dysfunction whereas the control group increased in pain, and physical and psychosocial dysfunction. There were no concomitant changes in reported daily activity levels. These results show that lumbar extension exercise is beneficial for strengthening the lumbar extensors and results in decreased pain and improved perceptions of physical and psychosocial functioning in chronic back pain patients. However, these improvements were not related to changes in activities or psychological distress.

[The prevention of mucosal lesions during oropharyngeal irradiation with a dental-filling shield]

In patients with metallic dental fillings radiation therapy to the oral cavity can cause mucous membrane lesions, which are more severe than expected. They appear as circumscribed erosions, opposite to metallic fillings and are caused by an increase in radiation dose through secondary radiation due to the higher density and atomic number of the filling material. This dose increase can be directly measured with 0.1 mm thin sheets of graphite-loaded TLD's (LiF, Vinten). For Co-60 gamma rays a commercial amalgam filling caused a dose increase by a factor of 1.7. The half value layer for this additional radiation was measured to be approximately 0.4 mm tissue. In order to avoid painful mucous membrane ulcerations which are even more a problem if hyperfractionated treatment schedules are used, we constructed individual dental shields for each patient. As shielding material we used a dental impression material (Optosil P+1 Bayer). This method was tested in 35 patients, in all of them circumscribed mucous membrane ulcerations could be avoided. The method proved to be fast and simple and was very well tolerated by all patients.

Aerobic glycolysis in the retina of the crab Ocypode ryderi

Our experiments on the isolated and superfused crab retina reveal that pronounced gradients for PO2 and pH exist in this tissue. The PgO2 profiles and a delayed recovery of the PgO2 after hypoxia seem to be a consequence of the oxygen consumption inside the tissue, as much as both characteristics can be abolished by impairment of electron transport in the respiratory chain after application of antimycin A. The pH profile is obviously created by a production and steady release of lactate, which could be measured in the superfusate. As this lactate release is occurring inspite of a sufficient oxygen supply and consumption, it can be concluded that this tissue performs aerobic glycolysis.

A Canadian multicenter study with Zaditen (ketotifen) in the treatment of bronchial asthma in children aged 5 to 17 years

One hundred thirty-eight children with chronic asthma, requiring daily treatment with bronchodilators, took part in a 7-month, double-blind, multicenter clinical study. Patients were randomized into two groups, and after a 1-month baseline, were administered Zaditen (ketotifen), 1.0 mg twice daily, or an identical placebo for a period of 6 months. After 10 weeks of receiving the study medication, bronchodilator use was reduced or stopped. In the Zaditen-treated group, 60% of the children taking theophylline were able to stop its use completely, compared to 34% of the patients taking placebo (p less than 0.05). Of the patients who were unable to stop taking theophylline, the Zaditen-and placebo-treated groups recorded average dosage reductions of 62% and 26%, respectively. These differences were statistically significant (p less than 0.05). Thus, a high percentage of patients in the placebo-treated group maintained asthma symptom control with theophylline, whereas most of the Zaditen-treated patients could stop using this medication. Although pulmonary function readings improved in both groups, those patients taking Zaditen demonstrated earlier improvement and greater changes from baseline. Significant differences (p less than 0.05) in favor of Zaditen were found for reduction of concomitant medications, patient's global evaluation, physician's clinical evaluations, incidence of emergency room visits for asthma, and upper respiratory tract infections. No unexpected side effects were observed. It is concluded that Zaditen is an effective medication for long-term control of asthma in children.