Impact of enhancements in the local effect model (LEM) on the predicted RBE-weighted target dose distribution in carbon ion therapy

Biological optimization for treatment planning in carbon ion therapy is currently based on the first version of the local effect model (LEM I). Further developments implemented in the latest version (LEM IV) allowed to predict more accurately the Relative Biological Effectiveness (RBE) in-vitro. The main goal of this study is to compare the LEM IV against LEM I under treatment-like conditions for idealized target geometries. Therefore, physical dose distributions resulting from the biological optimization with LEM I were used to recalculate the RBE-weighted dose distribution based on LEM IV. Input parameters representing the clinical endpoints late toxicity in the central nervous system and the tumor control for chordoma were chosen to investigate the impact of changes on the predicted isoeffective dose levels. The recalculated RBE-weighted dose distributions show an increase within the target region, and the mean RBE-weighted dose values are dependent on the geometry and decrease with increasing target dimension. The differences between predictions of LEM IV and LEM I are less than 10% for typical tumor volumes treated in the pilot project at GSI. Median RBE-weighted doses predicted by LEM IV in the target region are consistent with clinically observed dose-response behavior as demonstrated by comparison to the 5-year local control curve for skull base chordoma.

[Cyclic vomiting syndrome (CVS) in adults - frequently overlooked?]

CVS (cyclic vomiting syndrome) is a functional disorder that can occur in all age groups. Adults typically develop CVS in middle age (around the 35th year of life). CVS is characterised by recurrent stereotypic episodes of nausea and vomiting lasting hours or some days. Between these episodes there are intervals free of symptoms. The main symptoms include nausea, vomiting and often abdominal pain. CVS is a rare disorder in adult patients. Because of the lack of awarness, making the correct diagnosis is not easy und often delayed for some months or years. There is no specific test to secure the diagnosis. The accurate diagnosis is based on the typical anamnestic report and the exclusion of other disorders associated with a recurrent vomiting. No standard evidence-based treatment is currently available either to manage the acute vomiting episode or to manage the prophylactic therapy. For the acute treatment of the vomiting episodes antiemetic, antimigraine and sedative medications were used. The medications frequently used for the prophylactic therapy are amitriptyline and propranolol.

[The influence of cardiopulmonary bypass operation on the biodistribution of 99mTc-HMPAO-labelled granulocytes - Evaluation in pigs by planar scintigraphy and section-analyses]

AIM

of the study was to evaluate the influence of an extra corporal perfusion (cardiopulmonary bypass operation - cpb) on activation and biodistribution of (99m)Tc labelled granulocytes in pigs with and without inhibition of the granulocytes by a leukocyte inhibition module (LIM). The cpb is often related to an activation of granulocytes resulting in an inflammatory answer. The biological mechanisms are unsolved yet. First trials of our group showed that LIM may inhibit the activation of neutrophils and therefore antagonize a cpb-caused impairment of cardiac function. This study is the continuation of these experiments with a higher number of animals and the focus on scintigraphic imaging. ANIMALS, MATERIAL, METHODS: 39 German landrace pigs were subdivided into three groups: group A (control) median sternotomy without cpb, group B with cpb, group C with LIM in addition to cpb. After labelling with (99m)Tc-HMPAO autologues granulocytes were reinjected. Subsequently to cpb, the animals underwent scintigraphic imaging. Quantification was performed with ROI evaluation and with tissue samples (section analysis) examined in a well counter.

RESULTS

A high uptake of (99m)Tc-HMPAO was found in the liver. The count rates in brain, heart, lung, spleen and kidneys were far below. The amount of 99mTc-activity in the organ related to the half life corrected administered activity [%] was for the tissue samples (group A/B/C): brain 0.01/0.02/0.03; lung 12.1/8.3/11.5; heart 0.35/0.54/0.42; kidney 1.24/0.87/1.02; spleen 4.0/4.0/4.5, liver 16.8/20.9/19.6. The count rates determined by ROI-evaluation of the scintigraphic images related to the total count rate in the image [%] were (group A/B/C): brain 1.1/0.9/1.0; lung 15.6/10.4/12.2; heart 4.0/3.5/3.4; kidney 4.0/2.9/3.2; spleen 7.6/7.7/9.5, liver 23.1/36.7/31.4. A significant difference in the tracer uptake between the groups could neither be detected by scintigraphic imaging nor evaluation of tissue samples.

CONCLUSION

Scintigraphic imaging as well as section analysis showed a comparable biodistribution of the tracer. Therefore, the initial results of our group were not confirmed with a considerably higher number of animals. Neither cpb nor the use of the LIM influenced distribution of 99mTc-labelled granulocytes in pigs significantly.

[Recommendations for the treatment of thoracolumbar and lumbar spine injuries]

This paper gives recommendations for treatment of thoracolumbar and lumbar spine injuries. The recommendations are based on the experience of the involved spine surgeons, who are part of a study group of the "Deutsche Gesellschaft für Unfallchirurgie" and a review of the current literature. Basics of diagnostic, conservative, and operative therapy are demonstrated. Fractures are evaluated by using morphologic criteria like destruction of the vertebral body, fragment dislocation, narrowing of the spinal canal, and deviation from the individual physiologic profile. Deviations from the individual sagittal profile are described by using the monosegmental or bisegmental end plate angle. The recommendations are developed for acute traumatic fractures in patients without severe osteoporotic disease.

Fusion neutron detector for time-of-flight measurements in z-pinch and plasma focus experiments

We have developed and tested sensitive neutron detectors for neutron time-of-flight measurements in z-pinch and plasma focus experiments with neutron emission times in tens of nanoseconds and with neutron yields between 10(6) and 10(12) per one shot. The neutron detectors are composed of a BC-408 fast plastic scintillator and Hamamatsu H1949-51 photomultiplier tube (PMT). During the calibration procedure, a PMT delay was determined for various operating voltages. The temporal resolution of the neutron detector was measured for the most commonly used PMT voltage of 1.4 kV. At the PF-1000 plasma focus, a novel method of the acquisition of a pulse height distribution has been used. This pulse height analysis enabled to determine the single neutron sensitivity for various neutron energies and to calibrate the neutron detector for absolute neutron yields at about 2.45 MeV.

Integrated constructed wetlands: water management as a land-use issue, implementing the 'Ecosystem Approach'

Awareness of the need for social, economic and environmental coherence in the management of water is becoming evermore apparent. Water supply as well as treatment is becoming more costly; a challenge that is not only limited to developing countries. The use of wetlands, natural and constructed, is now more widely accepted as a means of tackling a range of problems in water management to deliver this coherence. The use of 16 Integrated Constructed Wetlands that mimic shallow, emergent-vegetated, palustrine wetlands in a 2,500 ha catchment in County Waterford, Southeast Ireland, has shown a number of distinct advantages in implementing the all encompassing 'Ecosystem Approach', addressing the key elements for sustainable water management in an intensively used agricultural area. The significant increase in water quality, biodiversity, social amenities and acceptance by the local rural community provided by this 'real' field-scale demonstration show the benefits that such a joined-up approach can have on catchment management in the widest sense.

Runoff infiltration, a desktop case study

The use of sustainable drainage systems (SuDS) or best management practice is becoming increasingly common. However, rather than adopting the preferred 'treatment train' implementation, many developments opt for end-of-pipe control ponds. This paper discusses the use of SUDS in series to form treatment trains and compares their potential performance and effectiveness with end-of-pipe solutions. Land-use, site and catchment characteristics have been used alongside up-to-date guidance, Infoworks CS and MUSIC to determine whole-life-costs, land-take, water quality and quantity for different SuDS combinations. The results presented show that the use of a treatment train allows approaches differing from the traditional use of single SuDS, either source or 'end-of-pipe', to be proposed to treat and attenuate runoff. The outcome is a more flexible solution where the footprint allocated to SUDS, costs and water quality can be managed differently to fully meet stakeholder objectives.

The synergy of permeable pavements and geothermal heat pumps for stormwater treatment and reuse

The use of permeable pavement systems with integrated geothermal heat pumps for the treatment and recycling of urban runoff is novel and timely. This study assesses the efficiency of the combined technology for controlled indoor and uncontrolled outdoor experimental rigs. Water quality parameters such as biochemical oxygen demand, nutrients, total viable heterotrophic bacteria and total coliforms were tested before and after treatment in both rigs. The water borne bacterial community genomic deoxyribonucleic acid (DNA) was analyzed by polymerase chain reaction (PCR) amplification followed by denaturing gradient gel electrophoresis (DGGE) and was further confirmed by DNA sequencing techniques. Despite the relatively high temperatures in the indirectly heated sub-base of the pavement, potentially pathogenic organisms such as Salmonella spp., Escherichia coli, faecal Streptococci and Legionella were not detected. Moreover, mean removal rates of 99% for biochemical oxygen demand, 97% for ammonia-nitrogen and 95% for orthophosphate-phosphates were recorded. This research also supports decision-makers in assessing public health risks based on qualitative molecular microbiological data associated with the recycling of treated urban runoff.

Microsurgically induced pure arterial aneurysm model in rats

INTRODUCTION

The aim of the study was to develop a reliable and reproducible arterial aneurysm model for microsurgical training and further research with dimensions comparable to those encountered in aneurysms in humans.

METHODS

The arterial aneurysm models were created microsurgically at the bifurcation of the abdominal aorta using a graft of the carotid artery in 20 Wistar rats.

RESULTS

The aneurysms were created successfully and no complications occurred. The average volume of this arterial aneurysm model was 35.19±5.64 mm (3). The time required to create this kind of aneurysm was 192±14.4 min. The central zone of blood inflow into the aneurysm was not affected by any thrombus formation.

CONCLUSION

The presented model at the aortic bifurcation in the rat is reliable and immediately available for microsurgical and technical training as well as for scientific studies on aneurysms. Since this kind of model also reproduces arterial aneurysms, basic techniques such as suturing and microtechniques needed for the dissection and repair of vessels can be taught during its creation.

Monitoring of WT1 expression in PB and CD34(+) donor chimerism of BM predicts early relapse in AML and MDS patients after hematopoietic cell transplantation with reduced-intensity conditioning

Relapse of malignant disease remains the major complication in patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) after hematopoietic cell transplantation (HCT) with reduced-intensity conditioning (RIC). In this study, we investigated the predictive value of disease-specific markers (DSMs), donor chimerism (DC) analysis of unsorted (UDC) or CD34(+) sorted cells and Wilms' tumor gene 1 (WT1) expression. Eighty-eight patients with AML or MDS were monitored after allogenic HCT following 2 Gy total-body irradiation with (n=84) or without (n=4) fludarabine 3 × 30 mg/m(2), followed by cyclosporin A and mycophenolate mofetil. DSMs were determined by fluorescence in situ hybridization (FISH) and WT1 expression by real-time polymerase chain reaction. Chimerism analysis was performed on unsorted or CD34(+) sorted cells, by FISH or short tandem repeat polymerase chain reaction. Twenty-one (24%) patients relapsed within 4 months after HCT. UDC, CD34(+) DC and WT1 expression were each significant predictors of relapse with sensitivities ranging from 53 to 79% and specificities of 82-91%. Relapse within 28 days was excluded almost entirely on the basis of WT1 expression combined with CD34(+) DC kinetics. Monitoring of WT1 expression and CD34(+) DC predict relapse of AML and MDS after RIC-HCT.

Anthracycline rechallenge using pegylated liposomal doxorubicin in patients with metastatic breast cancer: a pooled analysis using individual data from four prospective trials

BACKGROUND

The aim of this study was to determine the activity of anthracycline rechallenge using pegylated liposomal doxorubicin (PLD) in patients with metastatic breast cancer (MBC) previously treated with conventional anthracyclines.

METHODS

Pooled individual data from four prospective trials were used, and the primary end point of the pooled analysis was clinical benefit rate (CBR). The studies comprised 935 patients, of whom 274 had received PLD in the metastatic setting after prior exposure to conventional anthracyclines (rechallenge population).

RESULTS

The majority of patients were heavily pretreated. Previous anthracycline therapy was administered in the adjuvant (14%) or metastatic setting (46%), or both (40%). The overall CBR from rechallenge with PLD was 37.2% (95% CI, 32.4-42.0). In univariate analyses, the CBR was significantly higher in patients with less exposure to prior chemotherapy, in taxane-naive patients, and in patients with a favourable Eastern Cooperative Group performance status of 0 vs 1 vs 2 (53.3 vs 35.5 vs 18.2%; P<0.001). In multivariate analyses, performance status proved to be the only independent predictor of the CBR achieved with PLD rechallenge (P=0.038). There was no statistically significant difference in CBR regarding the setting, cumulative dose of and/or resistance to prior anthracyclines, or time since prior anthracycline administration.

CONCLUSION

Anthracycline rechallenge using PLD is effective in patients with MBC who have a favourable performance status, regardless of setting, resistance, cumulative dose or time since prior conventional anthracycline therapy.