Main pulmonary artery diameter in combination with cardiovascular biomarkers: new possibilities to identify pulmonary hypertension in patients with severe aortic valve stenosis

BACKGROUND

Echocardiography is currently the noninvasive method of choice to screen patients with severe aortic valve stenosis (AS) for pulmonary hypertension (PH) by estimating systolic pulmonary artery pressure (sPAP). However, radiological options are also available by determining the main pulmonary artery (MPA) diameter in the setting of CT angiography. The aim of the present study was to compare cardiovascular biomarkers with the MPA diameter to allow other ways of detecting PH in patients with severe AS.

METHODS

One hundred ninety-four patients with severe AS undergoing transcatheter aortic valve replacement (TAVR) were included in this study and were divided into two groups based on the CT-angiographically determined MPA diameter. In accordance with ESC guidelines, a cut-off value of 29 mm was determined in this study, with the absence of PH defined by an MPA diameter <29 mm (N79/194) and the presence of PH defined by an MPA diameter ≥29 mm (115/194). Immediately before interventional aortic valve replacement, blood samples were drawn from the subjects and relevant cardiovascular biomarkers such as BNP, cTnI, GDF-15, H-FABP, IGF-BP2 and suPAR were assessed.

RESULTS

Patients with an MPA diameter ≥29 mm had significantly higher BNP (P=0.004), cTnI (P=0.039) and H-FABP (P=0.015) plasma levels, whereas GDF-15 (P=0.140), IGF-BP2 (P=0.088) and suPAR (P=0.140) showed no significant differences. In addition, cut-off values were calculated to predict an MPA diameter ≥29 mm. Significant results were shown with 1634.00 pg/mL for BNP (P=0.004), with 16.50 pg/mL for cTnI (P=0.039) and with 1.16 ng/mL for H-FABP (P=0.016). In a combined biomarker analysis, the 2-way combination of BNP and IGF-BP2 (AUC 0.671; 95%CI 0.538-0.805; P=0.023) and the 3-way combination of BNP, H-FABP and IGF-BP2 (AUC 0.685; 95%CI 0.551-0.818; P=0.015) showed the best results. Biomarker follow-up at 3 and 12 months after TAVR did not require additional information gain. Regarding 1-year survival, no significant difference could be detected between patients with an MPA diameter<29 mm compared to patients with ≥29 mm (log-rank test: P=0.262).

CONCLUSIONS

The MPA diameter remains a controversial parameter for the detection of PH in patients with severe AS. Standing on its own, this non-invasive parameter may not be precise enough to detect PH accurately. Combining this parameter with several biomarkers did not provide significant additional information.

A comparison of thyroidal protection by iodine and perchlorate against radioiodine exposure in Caucasians and Japanese

Radioactive iodine released in nuclear accidents may accumulate in the thyroid and by irradiation enhances the risk of cancer. Radioiodine uptake into the gland can be inhibited by large doses of stable iodine or perchlorate. Nutritional iodine daily intake may impact thyroid physiology, so that radiological doses absorbed by the thyroid as well as thyroid blocking efficacy may differ in Japanese with a very rich iodine diet compared to Caucasians. Based on established biokinetic-dosimetric models for the thyroid, we derived the parameters for Caucasians and Japanese to quantitatively compare the effects of radioiodine exposure and the protective efficacy of thyroid blocking by stable iodine at the officially recommended dosages (100 mg in Germany, 76 mg in Japan) or perchlorate. The maximum transport capacity for iodine uptake into the thyroid is lower in Japanese compared to Caucasians. For the same radioiodine exposure pattern, the radiological equivalent thyroid dose is substantially lower in Japanese in the absence of thyroid blocking treatments. In the case of acute radioiodine exposure, stable iodine is less potent in Japanese (ED50 = 41.6 mg) than in Caucasians (ED50 = 2.7 mg) and confers less thyroid protection at the recommended dosages because of a delayed responsiveness to iodine saturation of the gland (Wolff-Chaikoff effect). Perchlorate (ED50 = 10 mg in Caucasians) at a dose of 1000 mg has roughly the same thyroid blocking effect as 100 mg iodine in Caucasians, whereas it confers a much better protection than 76 mg iodine in Japanese. For prolonged exposures, a single dose of iodine offer substantially lower protection than after acute radioiodine exposure in both groups. Repetitive daily iodine administrations improve efficacy without reaching levels after acute radioiodine exposure and achieve only slightly better protection in Japanese than in Caucasians. However, in the case of continuous radioiodine exposure, daily doses of 1000 mg perchlorate achieve a high protective efficacy in Caucasians as well as Japanese (> 0.98). In Caucasians, iodine (100 mg) and perchlorate (1000 mg) at the recommended dosages seem alternatives in case of acute radioiodine exposure, whereas perchlorate has a higher protective efficacy in the case of longer lasting radioiodine exposures. In Japanese, considering protective efficacy, preference should be given to perchlorate in acute as well as prolonged radioiodine exposure scenarios.

[Is compression therapy contraindicated for lower leg erysipelas? : Results of a retrospective analysis]

In many medical expert recommendations and guidelines, the use of compression therapy for acute erysipelas is designated as a contraindication. Due to the sometimes massive oedema, compression therapy is nevertheless used in some clinics. This led to the question whether compression therapy for erysipelas of the lower leg actually leads to complications due to the acute infection and thus represents a contraindication. For the period 01 January 2018 to 30 June 2019, the records of 56 inpatients with acute erysipelas of the lower leg who received compression therapy in addition to systemic antibiotic therapy were retrospectively evaluated. The duration of inpatient treatment, the infection parameters determined as part of the ward routine and any complications that occurred were evaluated. While treated as inpatients the blood parameters for infection clearly dropped. Compression therapy was started on admission day in 92.9% of patients and continued until discharge. None of the patients showed an increase in fever or clinical signs of sepsis during the hospital stay. In this retrospective analysis it could be shown for the first time that compression therapy does not cause a clinical worsening or trigger a septic clinical picture in patients with acute erysipelas. Therefore, the authors consider the declaration of acute erysipelas as contraindication for compression therapy as not justified.

Cytogenetic Analysis After Temporary Residence in the Area of the Uncontrolled Ruthenium-106 Release in Russia in September 2017

In September and October 2017, elevated atmospheric ruthenium contamination was measured in several European countries. The most probable origin of this release of radionuclides was reconstructed to be the Southern Ural region. During that time, five workers from a German company stayed up to 2 wk about 120 km from the Chelyabinsk region in Ekaterinburg, Russia. No clinical symptoms were reported during or after the suspected radiation exposure, and no internal contamination was found in whole-body measurements. However, to investigate radiation protection issues and to clarify the workers' situation in order to reassure them, as they planned to continue working in Ekaterinburg, our laboratory was urgently requested by the company's occupational physician to perform biodosimetry using dicentric analysis to determine if the workers have been exposed to radiation by incorporation of radionuclides. The workers' dicentric yields have been compared to reference data of background frequencies in unexposed individuals, but, as it is not reasonable to quantify individual absorbed radiation doses from internalized beta emitters due to various confounding factors, individual dose estimation has not been performed. Dicentric frequencies for two workers differed significantly from the mean laboratory background level, which could have been induced by an exposure to incorporated radionuclides due to beta emissions by Ru or to gamma irradiation by the decay nuclide of Ru. However, the maximum absorbed radiation doses calculated for a resident in the Ru-contaminated area during that time does not correspond to the observed dicentric frequencies. It cannot be excluded that their dicentric frequencies were already elevated before September 2017, potentially induced by an earlier radiation exposure to diagnostic x rays or even by chance.

A quantitative comparison of the chemo- and radiotoxicity of uranium at different enrichment grades

OBJECTIVE

The radiotoxic effects of uranium are often in the focus of the public fears but the chemical toxic effects of uranium are reported to surpass radiation effects. As there is no uranium isotope that is not radioactive, it is not possible to study chemical effects fully independently from radiation effects. In order to quantitate and compare radio- and chemotoxicity, we determined the median lethal doses of uranium due to its chemical toxicity and calculated the absorbed radiological doses resulting from the ingestion or inhalation of corresponding amounts depending on the isotopic enrichment grade. Committed effective doses over 50 years are related to the stochastic health effects like cancer occurrence and can be converted to a loss of statistical life time (mean loss 0.4 day / mSv). The equivalent doses absorbed within a short time frame permits conclusion on the induction of deterministic effects (e.g. acute radiation sickness).

METHOD

Simulations were based on the biokinetic models of the International Commission for Radioprotection and performed using Integrated Modules for Bioassay Analysis software. Results were compared with the doses given by the calculator of the WISE uranium project. The fractions of the total doses absorbed within different time periods were derived from the respective areas under the activity-time curves in the whole body.

RESULTS

The distribution of the total dose on the organs and tissues depends on the invasion pathway and the solubility of the compound. In the case of inhalation, the absorption of the total dose is more protracted than after ingestion. The incorporation of depleted or natural uranium in lethal amounts due to nephrotoxicity does not lead to deterministic radiation effects and is associated with committed effective doses reaching at most about 200 mSv (proposed possible threshold for therapeutic interventions after accidental radionuclide incorporation). The inhalation of low enriched uranium leads to higher effective doses up to 690 mSv, but they are still insufficient to cause acute deterministic effects. Even highly enriched uranium seems not to induce radiation nephropathy, but deterministic effects on the hematopoetic system cannot be excluded in particularly sensitive patients. But the equivalent doses to the lungs associated with the inhalation of poorly soluble compounds of highly enriched uranium are in a range that may induce radiation pneumonitis.

CONCLUSION

Our findings give clear evidence that for depleted and natural uranium chemical toxicity is much more marked than radiotoxicity. However, this conclusion must not be drawn for enriched and in particular highly enriched compounds that besides stochastic effects may even cause deterministic radiation effects.

Transcatheter aortic valve replacement for pure aortic valve regurgitation: "on-label" versus "off-label" use of TAVR devices

INTRODUCTION

Transcatheter aortic valve replacement (TAVR) has become the mainstay of treatment for aortic stenosis in patients with high surgical risk. Pure aortic regurgitation (PAR) is considered a relative contraindication for TAVR; however, TAVR is increasingly performed in PAR patients with unfavorable risk profile. Herein, we aim to summarize available data on TAVR for PAR with special emphasis on "on-label" versus "off-label" TAVR devices.

METHODS AND RESULTS

Pubmed was searched for studies of patients undergoing TAVR for PAR. Primary outcome was 30 day-mortality. Pooled estimated event rates were calculated. Twelve studies including a total of 640 patients were identified until December 2017. Among these, 208 (33%) patients were treated with devices with CE-mark approval for PAR ("on-label"; JenaValve and J valve). Overall, the procedural success rate was 89.9% (95% CI 81.1-96.1%; I² 80%). Major bleeding was reported in 6.4% (95% CI 2.9-10.8%; I² 48%). All-cause mortality at 30 days was 10.4% (95% CI 7.1-14.2%; I² 20%). Stroke occurred in 2.2% (95% CI 0.9-3.9%; I² 0%). A permanent pacemaker was required in 10.7% (95% CI 7.3-14.6%; I² 23%). At 30 days after TAVR, ≥ moderate AR post-interventional was observed in 11.5% (95% CI 2.9-23.6%; I² 90%). In the "on-label"-group, success rate was 93.0% (95% CI 85.9-98.1%; I² 52%). 30-day-mortality was 9.1% (95% CI 3.7-16.0%; I² 36%). More than trace AR was present in 2.8% (95% CI 0.1-7.6%; I² 0%). Compared to first-generation devices, second-generation devices were associated with significantly lower 30-day-mortality (r = - 0.10; p = 0.02), and significantly higher procedural success rates (r = 0.28; p < 0.001). Compared to other second-generation devices, the use of J valve or JenaValve was not associated with altered mortality (r = 0.04; p = 0.50), rates of > trace residual AR (r = - 0.05; p = 0.65) but with a significantly higher procedural success (r = 0.15; p = 0.042).

CONCLUSION

Based on this summary of available observational data TAVR for PAR is feasible and safe in patients deemed inoperable. First-generation TAVR devices are associated with inferior outcome and should be avoided. The "on-label" use of PAR-certified TAVR devices is associated with a significantly higher procedural success rate and might be favorable compared to other second-generation devices.

Carcinoid heart disease involving the left heart: a case report and biomarker analysis

Herein, we report the case of a 67‐year‐old woman who was admitted to our hospital because of dyspnoea and oedema of the lower extremities. Transthoracic echocardiography revealed severe tricuspid and mitral regurgitation, and the leaflets of the tricuspid valve were found to be rigid and almost immobile. The plasma concentrations of serotonin and chromogranin A were elevated, and hence, suspicion for carcinoid heart disease was raised. In addition to the diagnostic workup and medical and surgical treatment, we analysed levels of novel cardiovascular biomarkers throughout the entire follow‐up by means of enzyme‐linked immunosorbent assay. A dopa positron emission tomography (DOPA‐PET) was conducted and showed a neoplasm in the terminal ileum. Tricuspid valve replacement, mitral valve repair, and a closure of the patent foramen ovale (PFO) were conducted. Two months later, hemicolectomy and liver segment resection were performed. The tumour was resected, and the diagnosis of a neuroendocrine tumour (NET) was confirmed. Throughout the follow‐up, we observed a decrease in the plasma levels of novel biomarkers [e.g. interleukin‐8 (IL‐8), soluble suppression of tumorigenicity‐2 (sST2), and heart‐type fatty acid‐binding protein (H‐FABP)] over the follow‐up period. In our case, carcinoid heart disease resulted in a severe tricuspid regurgitation as commonly seen in these patients. Moreover, a pre‐existent mitral regurgitation was likely aggravated by fibrotic remodelling, because a PFO has led to a right‐to‐left shunt and might have caused left heart involvement. As IL‐8 was associated with adverse outcomes in patients with NETs, and sST2 and H‐FABP were associated with adverse outcomes in patients with heart failure previously, these biomarkers could aid in the risk stratification of patients with NET.

Transcatheter aortic valve implantation without prior balloon valvuloplasty is associated with less pronounced markers of myocardial injury

BACKGROUND

Aortic valve stenosis is the most common valvulopathy in developed countries. Transcatheter aortic valve implantation (TAVI) is a therapeutic alternative in symptomatic patients at high or prohibitive perioperative risk. Predilatation by balloon aortic valvuloplasty (BAV) under rapid ventricular pacing (RVP) has been a routine part of TAVI. However, both RVP and BAV carry substantial risks and an increasing number of interventional centers are performing TAVI without predilatation (direct TAVI). A transient decrease of left ventricular function and elevated markers of myocardial injury after TAVI with predilatation were observed in previous studies. In this study, we investigated whether direct TAVI was associated with a similar increase in cardiac biomarkers and decrease in ejection fraction in a cohort of our patients.

METHODS

Consecutive patients undergoing TAVI without predilatation using a self-expanding system at a single center between April 2013 and December 2015 were followed up for one year and were retrospectively analyzed regarding mortality, safety and efficacy endpoints as well as common laboratory and echocardiographic parameters.

RESULTS

A total of 164 patients (83±6 years; 56% female) were included in the analysis. According to the Valve Academic Research Consortium 2 (VARC-2) criteria the technical success rate was 96.3% and 89.1% of patients remained free of a combined safety endpoint at 30 days. Mortality rates at 30 days and 1 year were 3.0% (N.=5) and 10.4% (N.=17), respectively. TAVI without predilatation was highly effective in lowering aortic valve peak velocity from 4.4±0.6 m/s before to 1.7±0.5 m/s (P<0.01), and mean pressure gradient across the valve from 48.7±15.1 mmHg to 8.3±4.5 mmHg (<0.05). Left ventricular function remained unaltered after the intervention (51±10% prior to TAVI and 51±9% post TAVI), whereas high sensitive troponin T (hs-TnT), a well-established marker for myocardial injury, increased significantly from 26 ng/L (interquartile range=18.00-44.00) to 119 ng/L (interquartile range=73.25-166.00, P<0.001) during this time. Notably, an increase in the plasma levels of hs-TnT >15 times the upper limit of normal was associated with mortality both one month and one year after TAVI.

CONCLUSIONS

TAVI without predilatation is feasible, safe and effective for aortic valve replacement in symptomatic patients with severe aortic stenosis who are at high perioperative risk. In contrast to a cohort of patients who underwent TAVI with predilatation previously published by another center, our patients did not suffer from transient impairment of left ventricular function. As a marker of myocardial injury, hs-TnT showed a less pronounced increase than reported previously. This might be a marker for a prognostic benefit as hs-TnT has been shown to be a strong predictor of outcome in patients undergoing TAVI. We conclude that direct TAVI is a less invasive option involving less myocardial stress.

Visualization and appearance of artifacts of leadless pacemaker systems in cardiac MRI : An experimental ex vivo study

Background

Leadless pacemaker systems are an important upcoming device in clinical rhythmology. Currently two different products are available with the Micra system (Medtronic) being the most used in the clinical setting to date. The possibility to perform magnetic resonance imaging (MRI) is an important feature of modern pacemaker devices. Even though the Micra system is suitable for MRI, little is yet known about its impact on artifacts within the images.

Objective

The aim of our ex vivo study was to perform cardiac MRI to quantify the artifacts and to evaluate if artifacts limit or inhibit the assessment of the surrounding myocardium.

Methods

After ex vivo implantation of the leadless pacemaker (LP) in a porcine model, hearts were filled with saline solution and fixed on wooden sticks on a plastic container. The model was examined at 1.5 T and at 3 T using conventional sequences and T2 mapping sequences. In addition, conventional X‑rays and computed tomography (CT) scans were performed.

Results

Correct implantation of the LP could be performed in all hearts. In almost all MRI sequences the right ventricle and the septal region surrounding the (LP) were altered by an artifact and therefore would sustain limited assessment; however, the rest of the myocardium remained free of artifacts and evaluable for common radiologic diagnoses. A characteristic shamrock-shaped artifact was generated which appeared to be even more intense in magnitude and brightness when using 3 T compared to 1.5 T.

Conclusion

The use of the Micra system in cardiac MRI appeared to be feasible. In our opinion, it will still be possible to make important clinical cardiac MRI diagnoses (the detection of major ischemic areas or inflammatory processes) in patients using the Micra system. We suggest the use of 1.5 T as the preferred method in clinical practice.

Soluble ST2 predicts 1-year outcome in patients undergoing transcatheter aortic valve implantation

BACKGROUND

Soluble ST2 (sST2) has been introduced as a novel biomarker in patients suffering from heart failure for risk stratification. In this study, we sought to investigate whether sST2 is useful for risk stratification and prediction of mortality in patients undergoing transcatheter aortic valve implantation (TAVI).

MATERIALS AND METHODS

A total of 274 patients undergoing TAVI were included in this study (149 female; age 81 ± 1 years; EUROSCORE 25 ± 1; STS score 3·8 ± 0·2). Plasma samples were obtained preinterventional and analysed for sST2. Patients were followed up 1 month and 1 year after TAVI.

RESULTS

In a Cox regression analysis, sST2 plasma concentration was associated with increased mortality (changes per pg/mL sST2 concentration; HR 1·00006 95% (1·00004-1·00009); P < 0·001). A cut-off by means of the Youden Index was calculated (10 070·27 pg/mL), and patients were retrospectively divided into two cohorts, in those above (31·3%) and those below (68·7%) this value. These two groups were then compared regarding mortality both after 30 days and 1 year: whereas 1-month mortality did not differ (7·0% vs. 10·3%, OR 1·50 95% CI (0·60-3·79; P = 0·46)), patients with a sST2 concentration above the cut-off of 10 070·27 pg/mL showed a significantly worse outcome after 1 year (49·2% vs. 23·2%; OR 3·21 95% CI (1·70-6·04); P < 0·001). After correction for confounders in a multivariate Cox regression analysis, sST2 (1·0002 95% CI (1·0001-1·0003); P = 0·001) concentration remained associated with mortality.

CONCLUSIONS

sST2 levels were associated with 1-year mortality after TAVI. Based on these results, we assume that sST2 might help to identify patients at high risk for death in whom conservative treatment should be considered.

[Compression therapy of venous leg ulcers in the decongestion phase]

Compression therapy is the basis for successful treatment in most patients with venous leg ulcers. Concerning compression therapy, the initial phase of decongestion and the following phase of maintenance should be differentiated. While in the maintenance phase (ulcer) stocking systems are now frequently recommended, in the decongestion phase compression bandages are mostly still used, which however are often inappropriately applied. In German-speaking countries, compression therapy with short-stretch bandages has a long tradition. However, their correct application requires good training and monitoring, which is often lacking in daily practice. Less error-prone treatment alternatives are multicomponent systems, some of which have an optical marker for the control of the correct subbandage pressure. In another new type of compression system, which is called adaptive or wrap bandages, the compression pressure can be adjusted using a Velcro fastener. Accompanying intermittent pneumatic compression therapy can also be used in the decongestion phase. Thus, there are now several different treatment options that can be used for the decongestion phase in patients with venous leg ulcers. Often bandages with short-stretch materials are very prone to errors and should in most cases be replaced by other compression systems today. The patient's preference, need, and capability should be considered when selecting the appropriate system for the individual patient.

Safety and efficacy of thiotepa-based conditioning for allogeneic transplantation in AML: a survey from the ALWP of the EBMT

This study evaluated the safety and efficacy of thiotepa-based regimens before allogeneic stem cell transplantation in 310 adult patients with AML. Disease status at the time of transplantation was CR1 in 50%, CR2+ in 23.5% and advanced disease in 26.5%. Transplantation was performed from haploidentical (35%), matched sibling (27%), unrelated (20%) or cord blood (18%) donors. As for safety: mucositis occurred in 46.8% of the patients and the cumulative incidence (CI) of sinusoidal obstruction syndrome was 4.0%. With a median follow-up of 37 months, the CI of acute GvHD grade>II was 26.5%, whereas CI of chronic GvHD was 28.1% at 3 years. CI for non-relapse mortality at 3 years was 38.4%, 49.7% and 45.4% for patients in CR1, CR2+ and advanced disease, respectively (P=0.10). Relapse incidence at 3 years was 20.2, 30.7 and 40.6% in these three respective groups (P=0.002). CI for 3-year leukemia-free survival and overall survival were 41.4% and 45.6% (CR1), 19.6% and 27.7% (CR2+), and 13.9% and 13.6% (advanced disease), respectively (P<10^-4 for both). Our data suggest that thiotepa-based conditioning therapy in AML is feasible, effective and safe, as investigated for sinusoidal obstruction syndrome and mucositis.

Analysis of Ambient Influences Affecting Interleukin-6 Secretion in the Context of Clinical Trials of Stem Cell Therapy for Myocardial Infarction

BACKGROUND

Contradictory results of large clinical trials of stem cell therapy in acute myocardial infarction (AMI) have impeded a wider clinical use. As signalling via paracrine factors in AMI has received more and more attention recently, we sought to compare processing protocols with special emphasis on interleukin-6 (IL-6), a factor of major relevance for triggering cardioprotective signals via STAT3 and PI3K.

METHODS

Bone marrow and peripheral blood mononuclear cells were processed according to protocols used in the REPAIR-AMI and ASTAMI study.

RESULTS

Keeping cells at higher temperatures significantly boosted secretion of IL-6. Moreover, the use of autologous serum and X-Vivo medium was superior over reagents used in the protocol of the ASTAMI study.

CONCLUSIONS

External influencing factors (higher temperature, use of a modern cell culture medium supplemented with serum) led to higher concentrations of IL-6. These results could provide an explanation for the superior results found in the REPAIR-AMI study.

The Impact of Time on Decorporation Efficacy After a "Dirty Bomb" Attack Studied by Simulation

Background: In the case of a nuclear or radiological incident, there is a risk of external and internal contamination with radionuclides in addition to external irradiation. There is no consensus whether decorporation treatment should be initiated right away on spec or pending the results of internal dosimetry to determine the indication. Method: Based on biokinetic models for plutonium-239, americium-241 and cesium-137, the efficacy of a decorporation treatment using DTPA or Prussian blue was simulated depending on the initiation time and the duration of treatment for different invasion pathways and physicochemical properties of the inhaled compounds. Results: For the same level of radioactivity incorporated, the committed effective dose increases with the speed of the invasion process. The impact of the initiation time of a decorporation treatment is particularly important when the absorption of the radionuclide is fast. Even if started early after incorporation, the therapeutic efficacy is less for americium-241 or cesium-137 compared to plutonium-239. Therapeutic efficacy increases with treatment duration up to about 90 days for plutonium-239 and cesium-137, whereas a prolongation of the treatment over this limit may further enhance efficacy in the case of americium-241. Conclusion: In the case of a nuclear incident, several fractions with different but a priori unknown physicochemical properties may be inhaled. Thus, decorporation therapy should be started as soon as possible after the incorporation of the radionuclide(s), as a loss of efficacy caused by a delay of treatment initiation possibly cannot be compensated later on. Treatment should be pursued for several months.

Reconsidering Current Decorporation Strategies after Incorporation of Radionuclides

In the case of a nuclear accident or a terrorist attack by a "dirty bomb," there is a risk of external and internal contamination with radionuclides in addition to external irradiation. Internal irradiation as a consequence of radionuclide incorporation is associated with a higher risk of stochastic radiation effects (e.g., tumors). Decorporation treatment will enhance the elimination of radionuclides and reduce the committed effective dose as a metric of stochastic health effects. Although treatment efficacy is better when started early, beginning the therapy without knowing the committed effective dose may unnecessarily expose the patient to the side effects of the medication. The question is: Delay the therapy to wait for the results of internal dosimetry or start the therapy promptly on spec? To prove insight into this question, a selective review of the literature was conducted. The importance of the initiation time of treatment in the efficacy of decorporation treatment can be explained with pharmacokinetic laws and first order processes determining the disposition of xenobiotics in the organism. Nevertheless, there is no internationally accepted standard on when to start a decorporation therapy (exception: iodide). The "precautionary approach," emphasizing the importance of the committed effective dose for the indication of treatment, is competing with the "urgent approach" advocating the administration of medication "a priori" within several hours. A review of the literature actually indicates that the most important drugs used for decorporation are well tolerated with few adverse effects. In consideration of the higher efficacy and the low side-effects of a short-term treatment, initiating decorporation therapy as soon as possible after internal contamination, even before the committed effective dose has been assessed, appears to be a reasonable approach. The decision of continuation or discontinuation of the therapy should be taken after internal dosimetry is completed on the basis of the committed effective dose.

Seminal fluid promotes in vitro sperm-oviduct binding in the domestic cat (Felis catus)

From many endangered or threatened species which are expected to profit from assisted reproduction techniques, mainly epididymal sperm of dead or freshly castrated males are available. These sperm had contact to epididymal secretion products but not to seminal fluid components. Notably, products of accessory sex glands have been shown in domestic animals to condition sperm for fertilization, in particular by mediating sperm-oviduct interaction. We report for the first time that motile epididymal sperm from domestic cats are able to bind to fresh oviduct epithelial cell explants from preovulatory females (median [min, max] of 10 [8, 16] and 10 [8, 17] sperm per 0.01 mm(2) explant surface from both isthmic and ampullar regions, respectively). More sperm attach to the explants when epididymal sperm were preincubated for 30 minutes with seminal fluid separated from electroejaculates of mature tomcats (median [min, max] of 17 [13, 25] and 16 [12, 21] sperm per 0.01 mm(2) explant surface from isthmus and ampulla, respectively). The proportion of bound sperm increased from a median of 54% to 62% by seminal fluid treatment. Sperm-oviduct binding could be facilitated by the decelerated sperm motion which was observed in seminal fluid-treated samples or supported by seminal fluid proteins newly attached to the sperm surface. Seminal fluid had no effect on the proportion of sperm with active mitochondria. Extent and pattern of sperm interaction in vitro were independent of explant origin from isthmus or ampulla. Sperm were attached to both cilia and microvilli of the main epithelial cell types present in all explants. In contrast to published sperm-binding studies with porcine and bovine oviduct explants where predominantly the anterior head region of sperm was attached to ciliated cells, the tails of some cat sperm were firmly stuck to the oviduct cell surfaces, whereas the heads were wobbling. Whether this response is a preliminary step toward phagocytosis or a precondition to capacitation and fertilization remains to be determined. In conclusion, treatment of epididymal sperm with seminal fluid or particular protein components should be considered in future investigations for its potential to improve the outcome of artificial insemination in felids.

Bortezomib administered subcutaneously is well tolerated in bortezomib-based combination regimens used in patients with multiple myeloma

OBJECTIVE

Bortezomib (Btz) has emerged as a standard of care in the treatment of patients with multiple myeloma (MM), but Btz-induced peripheral neuropathy (PNP) has a particularly negative impact on patients' quality of life. According to a recent study, PNP was significantly less frequent with subcutaneous administration of Btz. Here, we report our experience regarding the efficacy and tolerability of standard combination regimens in MM with subcutaneous Btz.

METHODS

14 consecutive patients with newly diagnosed MM were included in this analysis. Btz was used in different combination regimens (Btz with dexamethasone with/without thalidomide or Btz combined with melphalan and prednisone). Standard criteria were applied to evaluate response and toxicity.

RESULTS

Hematological toxicities occurred only at grades 1-2 and included anemia (71%) and thrombocytopenia (21%). Nonhematologic side effects at grades 1-2 were local skin reactions at the subcutaneous injection site, which were self-limited. No notable gastrointestinal toxicity was observed with subcutaneous Btz, and therefore routine use of intravenous hydration and antiemetics was abandoned. Overall response rate for transplant-eligible patients was 86%.

CONCLUSIONS

Our results confirm the improved toxicity profile of the subcutaneous administration of Btz in various standard Btz-based combination regimens. In addition, patient management with subcutaneous administration has been markedly ameliorated at our center.

Molecular dynamics simulations of mixed lubrication with smooth particle post-processing

A post-processing method for molecular dynamics (MD) simulations of friction based on the smooth particle approach is proposed, allowing--among other features--the introduction and evaluation of a solid-solid contact area arising due to direct asperity interaction. In order to illustrate the feasibility of this scheme, a large number of MD calculations of lubricated nanotribological systems with various asperity geometries and carefully selected numbers of lubricant molecules were carried out and analysed. In this manner, it is shown that the friction force as a function of load agrees very well with a three-parameter friction law which, in addition to the adhesion- and the load-controlled terms, contains a load-independent offset.

[Cardiology quality assessment in Germany--pro and contra]

The German National Institute for Quality in Healthcare has also developed a program of external quality assessment in the field of cardiology. Hospitals are committed to collect certain data of diagnostic coronary angiography, percutaneous coronary interventions and pacemaker implantations. If statistical abnormalities are observed a so called structured dialogue is implemented. The responsible physicians of the hospitals are asked to comment possible quality deficits. Appointed members of quality commissions examine the answers and can invite the responsible physicians for interviews or also visit the hospital. However the validity of the quality data is problematic, because audits or check-ups of quality assessment in place are lacking. Therefore the results should not be misused for a comparison or ranking of hospitals with each other. As long as the validity of the quality assessment has not been improved, the results should also not be accessible for other parties, such as health insurances.

Serum hepcidin concentration in chronic haemodialysis patients: associations and effects of dialysis, iron and erythropoietin therapy

BACKGROUND

Hepcidin, a liver-derived peptide induced by iron overload and inflammation, is a major regulator of iron homeostasis. As hepcidin decreases gastrointestinal iron absorption and recirculation from monocytes, over-expression is associated with the development of anaemia.

METHODS

We studied the associations between circulating hepcidin levels and various laboratory parameters related to anaemia and/or inflammation in 20 patients on chronic haemodialysis. Furthermore, we determined the impact of dialysis and iron and/or erythropoietin (rhEpo) supplementation therapy on hepcidin serum concentrations. The patients were withheld from iron and rhEpo for 2 weeks before study entry. Hepcidin was measured by liquid chromatography-mass spectrometry (LC-MS/MS); serum iron and haematological parameters, cytokines and pro-hepcidin by commercially available enzyme-linked immunosorbent assays (ELISA) or standard automated methods.

RESULTS

While hepcidin levels at baseline were not correlated to pro-hepcidin, interleukin-6 or transforming growth factor-beta concentrations, we found significant associations with reticulocyte count (r = -0.55; P = 0.015), serum iron (r = 0.7; P = 0.004) and ferritin levels (r = 0.63; P = 0.004) and transferrin saturation (r = 0.69, P = 0.001). Dialysis using either a high or a low flux biocompatible dialyser resulted in a significant decrease of hepcidin concentrations, which returned to pre-dialysis values before the next dialysis session. When studying the effects of anaemia treatment, we observed a significant reduction of hepcidin levels following administration of rhEpo but not iron.

CONCLUSIONS

Hepcidin levels in stable haemodialysis patients appear to reflect systemic iron load, but not inflammation. Due to the negative association between reticulocyte counts and hepcidin, the reduction of circulating hepcidin concentrations by dialysis and/or rhEpo treatment may positively affect erythropoiesis.

Decrease of proteinuria in a patient with adult‐onset Still's disease and glomerulonephritis after anti‐TNFα therapy

We report the case of a 41-year-old man diagnosed with Still's disease. Multiple disease-modifying anti-rheumatic drug (DMARD) therapies failed to induce disease remission or to prevent progressive joint destruction. The man presented with active arthritis and classical Still's rash accompanied by fever. Anti-tumour necrosis factor-alpha (TNFalpha) therapy was planned but during the medical check-up prior to the biological therapy, renal insufficiency with marked proteinuria (PU) was discovered. With PU of 912 mg/24 h a renal biopsy was performed and a histopathological evaluation revealed the diagnosis of a residual mesangio-proliferative immunocomplex-based glomerulonephritis (GN). After excluding contraindications, infliximab therapy was initiated and a good response of the arthritis was documented after 6 weeks. A significant decrease in PU (279 mg/24 h) was noted after the third infliximab infusion. Because of an allergic reaction during the fifth dose, the infliximab was discontinued. During the time frame without anti-TNFalpha therapy, active joint disease reoccurred and the proteinuria increased significantly. Because of the active disease entanercept therapy was initiated. The arthritis diminished and the PU was reduced markedly within 4 weeks. In the follow-up period of 12 months a good response to therapy was sustained. As described by other investigators, the joint disease showed a rapid and sustained response to anti-TNFalpha therapy. The decrease in proteinuria during biological therapy was notable. It was concluded that the significant decrease in PU in this patient was achieved by eliminating the inflammatory activity of the underlying kidney disease.

Estrogen attenuates left ventricular and cardiomyocyte hypertrophy by an estrogen receptor-dependent pathway that increases calcineurin degradation

Left ventricular (LV) hypertrophy commonly develops in response to chronic hypertension and is a significant risk factor for heart failure and death. The serine-threonine phosphatase calcineurin (Cn)A plays a critical role in the development of pathological hypertrophy. Previous experimental studies in murine models show that estrogen limits pressure overload-induced hypertrophy; our purpose was to explore further the mechanisms underlying this estrogen effect. Wild-type, ovariectomized female mice were treated with placebo or 17beta-estradiol (E2), followed by transverse aortic constriction (TAC), to induce pressure overload. At 2 weeks, mice underwent physiological evaluation, immediate tissue harvest, or dispersion of cardiomyocytes. E2 replacement limited TAC-induced LV and cardiomyocyte hypertrophy while attenuating deterioration in LV systolic function and contractility. These E2 effects were associated with reduced abundance of CnA. The primary downstream targets of CnA are the nuclear factor of activated T-cell (NFAT) family of transcription factors. In transgenic mice expressing a NFAT-activated promoter/luciferase reporter gene, E2 limited TAC-induced activation of NFAT. Moreover, the inhibitory effects of E2 on LV hypertrophy were absent in CnA knockout mice, supporting the notion that CnA is an important target of E2-mediated inhibition. In cultured rat cardiac myocytes, E2 inhibited agonist-induced hypertrophy while also decreasing CnA abundance and NFAT activation. Agonist stimulation also reduced CnA ubiquitination and degradation that was prevented by E2; all in vitro effects of estrogen were reversed by an estrogen receptor (ER) antagonist. These data support that E2 reduces pressure overload induced hypertrophy by an ER-dependent mechanism that increases CnA degradation, unveiling a novel mechanism by which E2 and ERs regulate pathological LV and cardiomyocyte growth.

[Perianal fistulas in Crohn's disease--biologicals and surgery: is it worthwhile?]

Perianal fistulas and abscesses are a common manifestation in Crohn's disease (CD), seen in about 30 - 40 % of the patients. Often they are combined with CD of the anal canal and occur as a complex system of fistulas. The evaluation of these fistulas can be done with endoscopic ultrasound or magnetic resonance imaging, the conceptual accuracy of both methods is high. There are accepted therapeutic concepts for surgery and for the conventional drug therapy according to the classification of the fistulas. In contrast, the therapeutic regimens for a complex perianal fistulising CD are not convincing, especially not for maintainance therapy. However, several studies about therapy with anti-TNF-alpha antibodies have shown good results while long-time results with other recent anti-TNF-alpha antibodies apart from infliximab are still lacking. In this review article we analyse the current literature and develop a stage-adapted therapy for the use of biologicals and surgery in fistulising perianal CD.

3D-Histological evaluation of surgery in dermatofibrosarcoma protuberans and malignant fibrous histiocytoma: Differences in growth patterns and outcome

AIMS

To evaluate the microscopic growth pattern of dermatofibrosarcoma protuberans (DFSP) and malignant fibrous histiocytoma (MFH) and the long-term outcome using 3D-histologic surgery with paraffin sections to cover complete margins and to detect subclinical spreads very sensitively.

METHODS

One hundred and one patients have been included comprising 70 DFSP, 31 MFH. Data from 87 patients treated since 1992 were collected prospectively.

RESULTS

Mean clinical tumor-size was 45 mm, mean histological tumor size 65 mm. A mean excision margin of 19 mm achieved negative margins. The histological infiltration shows an asymmetrical pattern with horizontal or vertical extension either cord-, sector- or multiple-like up to 70 mm in length, detectable by 3D-histology. Age and localization differed significantly between DFSP and MFH lesions. MFH tumors had a significantly deeper infiltration than DFSP. The mean follow up was 60 months. In 70 patients with DFSP one local recurrence after 62 months occurred, but no metastasis. 31 patients with MFH developed 8 local recurrences, and 4 metastases (lymph nodes and/ or lungs); 3 of them died of the disease, all 3 had a postoperative status of R1 (p=0.001).

CONCLUSIONS

There are significant differences in growth pattern and clinical outcome between DFSP and MFH. DFSP can be cured by surgery following 3D-histology with paraffin sections. MFH is significantly more malignant. After local R0-resection proofed by 3D-histology higher cure rates can be achieved.

17 Beta-estradiol differentially affects left ventricular and cardiomyocyte hypertrophy following myocardial infarction and pressure overload

BACKGROUND

We have shown previously that 17beta-estradiol (E2) increases left ventricular (LV) and cardiomyocyte hypertrophy after myocardial infarction (MI). However, E2 decreases hypertrophy in pressure overload models. We hypothesized that the effect of estrogen on cardiac hypertrophy was dependent on the type of hypertrophic stimulus.

METHODS AND RESULTS

Ovariectomized wild-type female mice (n = 192) were given vehicle or E2 treatment followed by coronary ligation (MI), transverse aortic constriction (TAC), or sham operation. Signaling pathway activation was studied at 3, 24, and 48 hours, whereas echocardiography and hemodynamic studies were performed at 14 days. MI induced early but transient activation of p38 and p42/44 MAPK pathways, whereas TAC induced sustained activation of both pathways. E2 had no effect on these pathways, but increased Stat3 activation after MI while decreasing Stat3 activation after TAC. MI caused LV dilation and decreased fractional shortening (FS) that were unaltered by E2. TAC caused LV dilation, reduced FS, and increased LV mass, but in this model, E2 improved these parameters. After MI, E2 led to increases in myocyte cross-sectional area, atrial natriuretic peptide (ANP) and beta-myosin heavy chain (MHC) gene expression, but E2 diminished TAC-induced increases ANP and beta-MHC gene expression.

CONCLUSIONS

These data demonstrate that the effects of E2 on LV and myocyte remodeling depend on the nature of the hypertrophic stimulus. The opposing influence of E2 on hypertrophy in these models may, in part, result from differential effects of E2 on Stat3 activation. Further work will be necessary to explore this and other potential mechanisms by which estrogen affects hypertrophy in these models.

Gene expression profiles of human proximal tubular epithelial cells in proteinuric nephropathies

In kidney disease renal proximal tubular epithelial cells (RPTEC) actively contribute to the progression of tubulointerstitial fibrosis by mediating both an inflammatory response and via epithelial-to-mesenchymal transition. Using laser capture microdissection we specifically isolated RPTEC from cryosections of the healthy parts of kidneys removed owing to renal cell carcinoma and from kidney biopsies from patients with proteinuric nephropathies. RNA was extracted and hybridized to complementary DNA microarrays after linear RNA amplification. Statistical analysis identified 168 unique genes with known gene ontology association, which separated patients from controls. Besides distinct alterations in signal-transduction pathways (e.g. Wnt signalling), functional annotation revealed a significant upregulation of genes involved in cell proliferation and cell cycle control (like insulin-like growth factor 1 or cell division cycle 34), cell differentiation (e.g. bone morphogenetic protein 7), immune response, intracellular transport and metabolism in RPTEC from patients. On the contrary we found differential expression of a number of genes responsible for cell adhesion (like BH-protocadherin) with a marked downregulation of most of these transcripts. In summary, our results obtained from RPTEC revealed a differential regulation of genes, which are likely to be involved in either pro-fibrotic or tubulo-protective mechanisms in proteinuric patients at an early stage of kidney disease.

Estrogen receptor alpha up‐regulation and redistribution in human heart failure

Clinical and animal studies suggest that estrogen receptors are involved in the development of myocardial hypertrophy and heart failure. In this study, we investigated whether human myocardial estrogen receptor alpha (ERalpha) expression, localization, and association with structural proteins was altered in end stage-failing hearts. We found a 1.8-fold increase in ERalpha mRNA and protein in end-stage human dilated cardiomyopathy (DCM, n=41), as compared with controls (n=25). ERalpha was visualized by confocal immunofluorescence microscopy and localized to the cytoplasm, sarcolemma, intercalated discs and nuclei of cardiomyocytes. Immunofluorescence studies demonstrated colocalization of ERalpha with beta-catenin at the intercalated disc in control hearts and immunoprecipitation studies confirmed complex formation of both proteins. Interestingly, the ERalpha/beta-catenin colocalization was lost at the intercalated disc in DCM hearts. Thus, the ERalpha/beta-catenin colocalization in the intercalated disc may be of functional relevance and a loss of this association may play a role in the progression of heart failure. The increase of total ERalpha expression may represent a compensatory process to contribute to the stability of cardiac intercalated discs.

The Impact of Immunological Parameters on the Development of Phantom Pain after Major Amputation

OBJECTIVES

To investigate the relationship between local and systemic inflammatory markers and phantom limb pain.

METHODS

In 39 consecutive patients undergoing major amputations nerve biopsies, serum and clinical data was collected. Patients were followed up for 12 months to report on the incidence and severity of phantom limb pain.

RESULTS

After 12 months, 78% of the surviving patients had phantom pain, the symptom usually commencing within 14 days of operation. The severity of macrophage infiltration within the nerve biopsy was negatively correlated to the inception of phantom pain ( P = 0.026). While serum TNF-alpha concentration was positively correlated to mortality ( P = 0.021).

CONCLUSIONS

The immune status existing before the amputation and the local immunological milieu influence the onset of phantom pain.

Upregulation of Myocardial Estrogen Receptors in Human Aortic Stenosis

Background— Estrogen receptor (ER)–mediated effects have been associated with the modulation of myocardial hypertrophy in animal models and in humans, but ER expression in the human heart and its relation to hypertrophy-mediated gene expression have not yet been analyzed. We therefore investigated sex- and disease-dependent alterations of myocardial ER expression in human aortic stenosis together with the expression of hypertrophy-related genes.

Methods and Results— ER-α and -β, calcineurin A-β, and brain natriuretic peptide (BNP) mRNA were quantified by real-time polymerase chain reaction in left ventricular biopsies from patients with aortic valve stenosis (n=14) and control hearts with normal systolic function (n=17). ER protein was quantified by immunoblotting and visualized by immunofluorescence confocal microscopy. ER-α mRNA and protein were increased 2.6-fold ( P =0.003) and 1.7-fold ( P =0.026), respectively, in patients with aortic valve stenosis. Left ventricular ER-β mRNA was increased 2.6-fold in patients with aortic valve stenosis ( P <0.0001). ER-α and -β were found in the cytoplasm and nuclei of human hearts. A strong inverse correlation exists between ER-β and calcineurin A-β mRNA in patients with aortic valve stenosis ( r =−0.83, P =0.002) but not between ER-α or -β and BNP mRNA.

Conclusions— ER-α and -β in the human heart are upregulated by myocardial pressure load.