Rare ^{40}K Decay with Implications for Fundamental Physics and Geochronology

Potassium-40 is a widespread, naturally occurring isotope whose radioactivity impacts subatomic rare-event searches, nuclear structure theory, and estimated geological ages. A predicted electron-capture decay directly to the ground state of argon-40 has never been observed. The KDK (potassium decay) collaboration reports strong evidence of this rare decay mode. A blinded analysis reveals a nonzero ratio of intensities of ground-state electron-captures (I_{EC^{0}}) over excited-state ones (I_{EC^{*}}) of I_{EC^{0}}/I_{EC^{*}}=0.0095±[over stat]0.0022±[over sys]0.0010 (68% C.L.), with the null hypothesis rejected at 4σ. In terms of branching ratio, this signal yields I_{EC^{0}}=0.098%±[over stat]0.023%±[over sys]0.010%, roughly half of the commonly used prediction, with consequences for various fields [27L. Hariasz et al., companion paper, Phys. Rev. C 108, 014327 (2023)PRVCAN2469-998510.1103/PhysRevC.108.014327].

99mTc-markierte Anti-CEA-Antikörper in der intraoperativen Diagnostik kolorektaler Karzinome

Eine stadiengerechte Therapie kolorektaler Malignóme setzt die exakte Kenntnis des Tumorstadiums voraus. Intraoperativ ist dies für die Beurteilung der Operationsradikalität und die Planung weiterführender adjuvanter oder palliativer Behandlungsmodalitäten unerläßlich. In einer kontrollierten prospektiven Studie, an der 20 Patienten teilnahmen, wurde versucht, den Stellenwert nuklearmedizinischer Untersuchungen unter diesem Aspekt zu evaluieren. Mit 99mTc markierte Antikörper gegen zelluläre CEA-Epitope wurden zur intraoperativen Szintimetrie eingesetzt. Die Meßergebnisse wurden mit jenen der etablierten Verfahren verglichen und histopathologisch überprüft. Die intraoperative Szintimetrie erlaubt die exakte Lokalisation metastatischer Absiedelungen. Die Radikalität der Operation kann zuverlässig festgestellt werden. Die Immunszintimetrie ermöglicht somit eine exakte Stadienzuordnung zu einem frühen und therapeutisch relevanten Zeitpunkt.

Nutrition care in patients with cancer: A retrospective multicenter analysis of current practice - Indications for further studies?

BACKGROUND & AIMS

Weight loss and malnutrition are frequent problems in oncology patients. The aim of this study was to get a perspective of the current practice of parenteral nutrition (PN) care in an outpatient setting and to improve patient-centered nutritional care.

METHODS

Fifty-three outpatient oncology centers participated in this observational study performed between July 2010 and March 2011. All participating centers entered data online into a web-based documentation form, containing a number of oncology patients, diagnoses, and detailed data about oncology patients receiving PN.

RESULTS

Two cohorts were analyzed. First cohort consisted of all oncology patients in quarter 04/2010. Second cohort consisted of patients with PN during the whole studying period. In the first cohort 2.46% (n = 626) of 25,424 oncology patients received PN. Most frequent diagnoses of patients receiving PN were gastric cancer (n = 119) and colorectal cancer (n = 104), however most stated diagnosis was "other" (n = 163). In the second cohort (n = 1137), a common indication for PN was impaired gastrointestinal passage (n = 177), although here again most stated reason was "other" (n = 924). In the course of the PN treatment, patients (n = 1137) showed a stable or slowly increasing body mass index (from 21.6 ± 3.8 kg/m(2) to 21.8 ± 3.5 kg/m(2)).

CONCLUSION

This is the largest study outlining the characteristics of oncology patients in the context of PN in German ambulatory centers. They confirm the important role of PN in the care of gastrointestinal cancer. Further studies have to be performed to identify if other indications than those mentioned in relevant guidelines can trigger initiation of PN.

The DRAGO gamma camera

In this work, we present the results of the experimental characterization of the DRAGO (DRift detector Array-based Gamma camera for Oncology), a detection system developed for high-spatial resolution gamma-ray imaging. This camera is based on a monolithic array of 77 silicon drift detectors (SDDs), with a total active area of 6.7 cm(2), coupled to a single 5-mm-thick CsI(Tl) scintillator crystal. The use of an array of SDDs provides a high quantum efficiency for the detection of the scintillation light together with a very low electronics noise. A very compact detection module based on the use of integrated readout circuits was developed. The performances achieved in gamma-ray imaging using this camera are reported here. When imaging a 0.2 mm collimated (57)Co source (122 keV) over different points of the active area, a spatial resolution ranging from 0.25 to 0.5 mm was measured. The depth-of-interaction capability of the detector, thanks to the use of a Maximum Likelihood reconstruction algorithm, was also investigated by imaging a collimated beam tilted to an angle of 45 degrees with respect to the scintillator surface. Finally, the imager was characterized with in vivo measurements on mice, in a real preclinical environment.

Determination of MBT-waste reactivity - An infrared spectroscopic and multivariate statistical approach to identify and avoid failures of biological tests

The Austrian Landfill Ordinance provides limit values regarding the reactivity for the disposal of mechanically biologically treated (MBT) waste before landfilling. The potential reactivity determined by biological tests according to the Austrian Standards (OENORM S 2027 1-2) can be underestimated if the microbial community is affected by environmental conditions. New analytical tools have been developed as an alternative to error-prone and time-consuming biological tests. Fourier Transform Infrared (FT-IR) spectroscopy in association with Partial Least Squares Regression (PLS-R) was used to predict the reactivity parameters respiration activity (RA(4)) and gas generation sum (GS(21)) as well as to detect errors resulting from inhibiting effects on biological tests. For this purpose 250 MBT-waste samples from different Austrian MBT-plants were investigated using FT-IR spectroscopy in the mid (MIR) and near infrared (NIR) area and biological tests. Spectroscopic results were compared with those from biological tests. Arising problems caused by interferences of RA(4) and GS(21) are discussed. It is shown that FT-IR spectroscopy predicts RA(4) and GS(21) reliably to assess stability of MBT-waste materials and to detect errors.

Approaches to assess biocover performance on landfills

Methane emissions from active or closed landfills can be reduced by means of methane oxidation enhanced in properly designed landfill covers, known as "biocovers". Biocovers usually consist of a coarse gas distribution layer to balance gas fluxes placed beneath an appropriate substrate layer. The application of such covers implies use of measurement methods and evaluation approaches, both during the planning stage and throughout the operation of biocovers in order to demonstrate their efficiency. Principally, various techniques, commonly used to monitor landfill surface emissions, can be applied to control biocovers. However, particularly when using engineered materials such as compost substrates, biocovers often feature several altered, specific properties when compared to conventional covers, e.g., respect to gas permeability, physical parameters including water retention capacity and texture, and methane oxidation activity. Therefore, existing measuring methods should be carefully evaluated or even modified prior to application on biocovers. This paper discusses possible strategies to be applied in monitoring biocover functionality. On the basis of experiences derived from investigations and large-scale field trials with compost biocovers in Austria, an assessment approach has been developed. A conceptual draft for monitoring biocover performance and recommendations for practical application are presented.

Mswi bottom ash for upgrading of biogas and landfill gas

A new upgrading process for biogas and landfill gas (LFG) has been designed recently by the authors' institute. The process uses the alkalinity of the fine fraction of bottom ash from municipal solid waste incineration (MSWI) for sorbing CO2 and H2S. Results from process development and optimisation are presented in this paper. It is expected that nearly pure CH4 can be produced for substitution of fossil fuels. Simultaneously, the leachability of MSWI bottom ash is clearly reduced.

Classification of waste materials using Fourier transform infrared spectroscopy and soft independent modeling of class analogy

Fourier transform infrared (FTIR) spectroscopy combined with multivariate data analysis is under development as a method to classify waste materials. The chemical composition of the sample is reflected by a series of regions of the infrared spectrum which are used as variables for multivariate data analysis. In this study, separated biowaste collection, mechanically-biologically treated waste (MBT-waste), and old landfill materials were collected to provide materials representing different stages of decomposition. A total of 819 FTIR absorbance spectra were recorded. Principal component analyses (PCA) were performed followed by soft independent modeling of class analogy (SIMCA) for classification of waste materials. Strong classification occurred for an analysis where spectral carbonate regions were included, and for another analysis when they were not. The SIMCA model enabled the differentiation and the classification of unknown samples according to the three categories in both cases. The classification methods developed here provide an assessment tool that regulatory authorities may wish to explore when assessing whether a treated waste from an uncertain process can be classed as compost or MBT-waste.

Application of FT-IR for assessment of the biological stability of landfilled municipal solid waste (MSW) during in situ aeration

Disposal of untreated municipal solid waste leads to gaseous emissions as well as liquid degradation products. In situ aeration is an emerging means for remediation of abandoned landfills. It aims at an accelerated mineralization and stabilization of waste organic matter and thus reduces significantly the emission potential of the site. In order to prove the success of the technique, evaluation of the biological stability of the aerated material has been suggested. Fourier Transform Infrared Spectroscopy (FT-IR) provides comprehensive information on the chemical composition of solid waste samples. Different stages of organic matter degradation are reflected by changes in the infrared spectral pattern. In the present study the feasibility of applying FT-IR for assessment of the stability of waste material derived from abandoned landfills and for in situ aeration process control was investigated. Waste samples derived in the course of pilot-scale and lab-scale aeration experiments were characterized by FT-IR (4000-400 cm(-1), KBr-technique, transmission mode) and a set of conventional parameters describing biological stability. The occurrence of distinct indicator bands was correlated with chemical and biological waste properties using 206 solid waste samples. Visual spectra interpretation was found to be appropriate in proving a reduced emission potential of initially rather reactive waste (respiration activity over 4 days (RA(4)) > 7 mg O(2) g(-1) DM) during aeration. Furthermore, cluster analysis was applied successfully to differentiate between original and aerated waste samples, even for rather stable material (RA(4) < 7 mg O(2) g(-1) DM), when visual spectra interpretation was limited.

[Abdominal dressing -- a new standard in therapy of the open abdomen following secondary peritonitis?]

INTRODUCTION

The management of patients with a laparostoma due to peritonitis is a challenge for every surgeon and intensivist. The goal of this study was to compare the different treatment strategies for the open abdomen: Abdominal Dressing (AD), the classic V.A.C. therapy (CV) and conventional open therapy (CT).

METHODS

Between 2001 and 2005 we identified 62 patients in 4 surgical departments in Austria who had to be treated with a laparostoma due to peritonitis. 27 patients were conventionally treated, 16 with the Classic V.A.C. therapy and 19 patients with V.A.C. abdominal dressing.

RESULTS

The mortality was 3/16 (14 %) in the AD group vs. 4/12 (21 %) patients in the CV group and 18/9 (59 %) in conventional therapy. There was no significant difference for survivors in the length of ICU stay: 26.6 +/- 23.0 days in the CT group, 34.6 +/- 30.2 days in the CV group and 38.9 +/- 27.2 days in the AD group. Apache II Score and Mannheimer Peritonitis Score showed no difference between the groups.

CONCLUSION

We found a reduction of mortality in the V.A.C. Abdominal Dressing group by approximately 40 % (AD: 14 %, CT: 59 %). Although we could identify a difference in age in our retrospective study we believe that V.A.C. Abdominal Dressing is the important factor for the different clinical outcome. These first results indicate the need for further prospective evaluation of the V.A.C. Abdominal Dressing therapy, to prove if a new standard in the therapy of the open abdomen is created.

Changes in carbon and nitrogen pool during in-situ aeration of old landfills under varying conditions

Emissions from old landfills via leachate and the gas phase are influenced by state and stability of the organic matter in the solid waste and by environmental conditions within the landfill. Remediation of landfills by means of in-situ aeration is one possibility to reduce these emissions. By establishing aerobic conditions, biological processes in the landfill are accelerated. To investigate the effects of this remediation technology, lab-scale experiments with column tests have been carried out. The main goal of the present work is to characterize the changes of the carbon and nitrogen compounds in the aerated solid waste, the leachate and the gas phase under varying conditions. The results demonstrate a clear reduction of emissions and a stabilization of the organic matter. Furthermore, it is shown that both the intensity of aeration and the amount of water affect biological processes to a certain extent. Even when columns were operated under anaerobic conditions after a long running period of aeration, the emissions remained low.

pH dependence of the relative hydrophobicity and lipophilicity of amino acids and peptides measured by aqueous two-phase and octanol-buffer partitioning

Partitioning of a series of free amino acids, their derivatives, and homo-oligopeptides in aqueous dextran-PEG two-phase systems and octanol buffer systems was examined at pH values from 2.0 up to 12.5. The pH-dependent partition behavior of free amino acids and peptides in the two-phase systems was compared with that of monofunctional drug-like compounds and found to be clearly different. The differences observed indicate that the information provided by the techniques of partitioning in octanol buffer (log(D)(pH)) and in aqueous two-phase systems, N(CH2), is different. It is suggested that the combination of the two descriptors, log(D) (lipophilicity) and N(CH2) (relative hydrophobicity), may be useful for QSAR analysis of the biological activities involving distribution and/or transport of chemical compounds in biological systems.

Management of municipal solid waste incineration residues

The management of residues from thermal waste treatment is an integral part of waste management systems. The primary goal of managing incineration residues is to prevent any impact on our health or environment caused by unacceptable particulate, gaseous and/or solute emissions. This paper provides insight into the most important measures for putting this requirement into practice. It also offers an overview of the factors and processes affecting these mitigating measures as well as the short- and long-term behavior of residues from thermal waste treatment under different scenarios. General conditions affecting the emission rate of salts and metals are shown as well as factors relevant to mitigating measures or sources of gaseous emissions.

Probe-guided surgery for colorectal cancer

Anti-CEA-scintigraphy turned out to be very reliable in detecting primary and recurrent colorectal cancer, its overall accuracy being more than 90%. The intraoperative application of this technology should provide similar results when focussing at extrahepatic tumor deposits, for example in lymph nodes, thus allowing accurate staging of the underlying disease. To test this hypothesis we launched the following feasibility study the results of which are compared to those reported in the recent literature. We investigated 20 patients, six with rectum and 14 with colon cancer. 24 hours before surgery they were intravenously given 1 ml of a fab'-fragment-antibody to CEA, labeled with 25 mCi of 99mTc (CEA-Scan). During surgery the radioactivity in lymph glands regional to the tumors was measured and compared to the much lower activity in healthy nodes. For this we used a scintillation probe (C-Trak, Care Wise, Inc., Morgan Hill, CA). All lymph nodes of interest were then excised and submitted to frozen section pathology. In 7 out of 20 cases scintimetry led to an up-staging of the disease. In addition we found metastatic spread to lymph nodes that were basically not regional to the primary tumor (retroperitoneum, renal hilum etc.). Scintimetry can precisely identify even very small tumor deposits. So it leads to accurate staging while surgery is still ongoing. In a further step the concept of sentinel node diagnosis, which is right now being clinically evaluated, may some day be applied in colorectal surgical oncology.

Can postoperative surveillance with serial CEA immunoscintigraphy detect resectable rectal cancer recurrence and potentially improve tumor-free survival?

BACKGROUND

This study was performed to determine if postoperative serial monitoring of rectal cancer patients can be performed with an immunoscintigraphic imaging test for carcinoembryonic antigen (CEA). It was also of interest to assess whether this test, in combination with standard monitoring procedures used in an intensive surveillance plan, can result in the identification of surgically salvageable patients.

STUDY DESIGN

Forty consecutive resected Dukes' B and C rectal cancer patients underwent a prospective, single-institution, surveillance trial of physical examination (including digital rectal examination), endoscopy, CT of the abdomen and pelvis, liver ultrasound, chest x-ray, blood CEA, and CEA immunoscintigraphy with arcitumomab (CEA-Scan, Immunomedics, Morris Plains, NJ) every 6 months for the first 2 years and every 12 months for the next 3 years after initial operation. Outcomes were compared with those from a similar group of 69 patients treated previously at the same institution but without CEA imaging.

RESULTS

A total of 219 CEA imaging studies were performed without any significant adverse effects or immune responses, and resulted in lesion sensitivity, specificity, accuracy, and positive and negative predictive values of 94.1%, 97.5%, 97.3%, 76.2%, and 99.5%, respectively. Of the 40 patients, 16 developed 22 surgically confirmed local or distant recurrences, and CEA imaging correctly disclosed 82% of these lesions pre-operatively. All of the patients found to have recurrences had at least one tumor site by CEA imaging; only 6 of 16 had elevated blood CEA titers. On a patient-basis, there was a sensitivity of 100%, a specificity of 79.2%, an accuracy of 87.5%, and positive and negative predictive values of 76.2% and 100%, respectively. The potential therapeutic benefit of serial arcitumomab imaging is suggested by the fact that 6 of 16 patients (37.5%) with recurrence underwent potentially curative second-look operations, compared with 6 of 69 (8.7%) of a comparable population studied at this institution during an earlier 6-year period, using all of the same tests except CEA imaging. None of the patients in this historic control group survived more than 21 months, although the mean survival of the six patients resected for cure in the study population was 35 months (range 11 to 69 months). During 6 years of followup, three of the six re-resected patients eventually died of cancer recurrence, two died from other causes (and were confirmed by necropsy to be tumor-free), and one patient is still free of disease in the sixth year. CEA scanning appeared to be more predictive of recurrence than blood CEA testing or other diagnostic modalities.

CONCLUSIONS

Arcitumomab inclusion in intensive surveillance of patients with resected rectal cancer can disclose tumor recurrence at a stage that allowed surgical salvage therapy in 37.5% of the 16 patients with recurrence who had second-look surgery, and in 19% the patients were free of disease during longterm followup. This pilot study suggests that a randomized prospective trial comparing standard surveillance procedures to the use of CEA imaging added thereto should be undertaken.

Relative hydrophobicity of organic compounds measured by partitioning in aqueous two-phase systems

Partitioning of a variety of organic compounds, the majority of which represent therapeutic drugs, was examined in an aqueous dextran-polyethylene glycol (Dex-PEG) two-phase system containing 0.15 M NaCl in 0.01 M sodium phosphate buffer at pH 7.3 and in an octanol-buffer (0.15 M NaCl in 0.01 M sodium phosphate buffer, pH 7.3) system. The possibility of introducing compounds to be partitioned in an aqueous two-phase system with dimethyl sulfoxide, and the effect of this solvent on the solute partitioning was explored. Relative hydrophobicity of the compounds was estimated and expressed in equivalent numbers of methylene units. Comparison of the results obtained for several subsets of compounds in the octanol-buffer and in aqueous Dex-PEG two-phase systems clearly demonstrates the advantage of aqueous two-phase partitioning for the hydrophobicity measurements over partitioning in octanol-buffer system.

High-Resolution X-ray Spectroscopy Close to Room Temperature

: Originally designed as position-sensitive detectors for particle tracking, silicon drift detectors (SDDs) are now used for high-count rate X-ray spectroscopy, operating close to room temperature. Their low-capacitance read-node concept places them among the fastest high-resolution detector systems. They have been used in a new spectrum of experiments in the wide field of X-ray spectroscopy: fluorescent analysis, diffractometry, materials analysis, and synchrotron experiments such as X-ray holography and element imaging in scanning electron microscopes. The fact that the detector system can be used at room temperature with good spectroscopic performance and at -10 degrees C with excellent energy resolution, avoiding liquid nitrogen for cooling and high-quality vacuum, guarantees a large variety of new applications, independent of the laboratory environment. A brief description of the device principles is followed by basics on low noise amplification. The performance results of a complete detector system are presented as well as some dedicated applications already realized, including use in a surface mapping instrument and use of a "mini-spectrometer" for the analysis of works of art. Fully depleted pn-charge-coupled devices (pn-CCDs) have been fabricated for the European X-ray Multi-Mirror mission (XMM) and the German X-ray satellite ABRIXAS, enabling high-speed, low-noise, position-resolving X-ray spectroscopy. The detector was designed and fabricated with a homogeneously sensitive area of 36 cm2. At -70 degrees C it has a noise of 4 e- rms, with a readout time of the total focal plane array of 4 msec. The maximum count rate for single photon counting was 10(5) cps under flat field conditions. In the integration mode, more than 10(9) cps can be detected at 6 keV. Its position resolution is on the order of 100 µm. The quantum efficiency is higher than 90%, ranging from carbon K X-rays (277 eV) up to 10 keV.

High-Resolution High-Count-Rate X-ray Spectroscopy with State-of-the-Art Silicon Detectors

For the European X-ray multi-mirror (XMM) satellite mission and the German X-ray satellite ABRIXAS, fully depleted pn-CCDs have been fabricated, enabling high-speed low-noise position-resolving X-ray spectroscopy. The detector was designed and fabricated with a homogeneously sensitive area of 36 cm(2). At 150 K it has a noise of 4 e(-) r.m.s., with a readout time of the total focal plane array of 4 ms. The maximum count rate for single-photon counting was 10(5) counts s(-1) under flat-field conditions. In the integration mode more than 10(9) counts s(-1) can be detected at 6 keV. Its position resolution is of the order of 100 micro m. The quantum efficiency is higher than 90% from carbon K X-rays (277 eV) up to 10 keV. New cylindrical silicon drift detectors have been designed, fabricated and tested. They comprise an integrated on-chip amplifier system with continuous reset, on-chip voltage divider, electron accumulation layer stabilizer, large area, homogeneous radiation entrance window and a drain for surface-generated leakage current. At count rates as high as 2 x 10(6) counts cm(-2) s(-1), they still show excellent spectroscopic behaviour at room-temperature operation in single-photon detection mode. The energy resolution at room temperature is 220 eV at 6 keV X-ray energy and 140 eV at 253 K, being achieved with Peltier coolers. These systems were operated at synchrotron light sources (ESRF, HASYLAB and NLS) as X-ray fluorescence spectrometers in scanning electron microscopes and as ultra low noise photodiodes. The operation of a multi-channel silicon drift detector system is already foreseen at synchrotron light sources for X-ray holography experiments. All systems are fabricated in planar technology having the detector and amplifiers monolithically integrated on high-resistivity silicon.

Phosphoenolpyruvate carboxykinase (GTP) gene transcription and hyperglycemia are regulated by glucocorticoids in genetically obese db/db transgenic mice

The molecular mechanisms underlying increased hepatic phosphoenolpyruvate carboxykinase (PEPCK) gene transcription and gluconeogenesis in type II diabetes are largely unknown. To examine the involvement of glucocorticoids and the cis-acting insulin response sequence (IRS, -416/-407) in the genetically obese db/db mouse model, we generated crosses between C57BL/KsJ-db/+ mice and transgenic mice that express -460 or -2000 base pairs of the rat PEPCK gene promoter containing an intact or mutated IRS, linked to a reporter gene. Transgenic mice expressing the intact PEPCK(460)-CRP (C-reactive protein) transgene bred to near homozygosity at the db locus were obese, hyperinsulinemic, and developed fasting hyperglycemia (389 +/- 26 mg/100 ml) between 4 and 10 weeks of age. Levels of CRP reporter gene expression were increased 2-fold despite severe hyperinsulinemia compared with non-diabetic non-obese transgenic mice. Reporter gene expression was also increased 2-fold in transgenic obese diabetic db/db mice bearing a mutation in the IRS, -2000(IRS)-hGx, compared with non-obese non-diabetic transgenic 2000(IRS)-hGx mice. Treatment of obese diabetic db/db transgenic mice with the glucocorticoid receptor blocker RU 486 decreased plasma glucose by 50% and reduced PEPCK, GLUT2, glucose-6-phosphatase, tyrosine aminotransferase, CRP, and hGx reporter gene expression to levels similar to those of non-obese normoglycemic transgenic mice. Taken together, these results establish that -460 bp of 5'-flanking sequence is sufficient to mediate the induction of PEPCK gene transcription in genetically obese db/db mice during the development of hyperglycemia. The results further demonstrate that the mechanism underlying increased expression of gluconeogenic enzymes in the db/db mouse requires the action of glucocorticoids and occurs independently of factors acting through the PEPCK IRS (-416/-407) promoter binding site.

[Probe-guided surgery of colorectal carcinoma]

Anti-CEA-scintigraphy turned out very reliable in detecting primary and recurrent colorectal cancer, its overall accuracy being more than 90 p.c. The intraoperative application of this technology should provide similar results when focussing at extrahepatic tumor deposits, for example in lymph nodes, thus allowing accurate staging of the underlying disease. To test this hypothesis we lauched the following feasibility-study the results of which are compared to those reported in the recent literature. We investigated 20 patients-six with rectum-, 14 with colon cancer, 24 hours before surgery they were intravenously given 1 ml of an fab-fragment-antibody to CEA, labeled with 25mCi of 99mTc (CEA-Scan). During surgery the radioactivity in lymph glands regionary for the tumors was measured and compared to the-much lower-activity in healthy nodes. For this we used a scintillation-probe (C-Trak). All lymph nodes of interest were-then excised and submitted to frozen section pathology. In 7/20 cases scintimetry led to an up-staging of the disease. In addition we found metastatic spread to lymph nodes that were basically not regionary for the primary tumor. Our results are confirmed by those of other investigators. Scintimetry can precisely identify even very small tumor deposits. So it leads to accurate staging when surgery is still on-going. In a next step the concept of sentinel-node-diagnosis, which is right now being clinically evaluated, may be applied is colorectal surgical oncology.

Silicon drift detectors with on-chip electronics for x-ray spectroscopy

The silicon drift detector (SDD) is a semiconductor device based on high resistivity silicon fully depleted through junctions implanted on both sides of the semiconductor wafer. The electrons generated by the ionizing radiation are driven by means of a suitable electric field from the point of interaction toward a collecting anode of small capacitance, independent of the active area of the detector. A suitably designed front-end JFET has been directly integrated on the detector chip close to the anode region, in order to obtain a nearly ideal capacitive matching between detector and transistor and to minimize the stray capacitances of the connections. This feature allows it to reach high energy resolution also at high count rates and near room temperature. The present work describes the structure and the performance of SDDs specially designed for high resolution spectroscopy with soft x rays at high detection rate. Experimental results of SDDs used in spectroscopy applications are also reported.

[Tc-99m-labeled anti-CEA antibodies in intraoperative diagnosis of colorectal cancer]

Stage-adjusted treatment of colorectal tumors requires precise knowledge of the extent of the underlying disease. Reliable staging is mandatory for intraoperative treatment planning. In this prospective trial monoclonal antibodies to CEA were labeled with 99mTc as tracer. Twenty patients were studied intraoperatively with a hand-held gamma detector. The results were compared to those obtained by all other diagnostic modalities and they were then confirmed by histopathology. Intraoperative scanning can reliably identify all tumor deposits and can confirm the radicality of the procedure. Thus, the use of immunoscintimetry is helpful in early decision making on adjuvant treatment modalities.

Anticarcinoembryonic antigen immunoscintigraphy with a 99mTc-Fab' fragment (Immu 4) in primary and recurrent colorectal cancer. A prospective study

Forty-seven patients were submitted to 68 radioimmunoscintigraphic investigations for primary or recurrent colorectal cancer. Immunoscintigraphy with Immu-4 correctly detected 28 primary colorectal cancers of 29 and 12 of 12 recurrent colorectal cancers. Overall accuracy was 93.75 percent in primary and 91.6 percent in recurrent colorectal cancer. Immunoscintigraphy had a decisive influence on treatment planning in every third primary colorectal cancer patient and was by far superior to CT scan in the detection of early recurrences, especially in patients with a history of abdominoperineal or low anterior resection. Immu-4 scintigraphy is a safe and convenient diagnostic approach to colorectal cancer. Because radioactivity is acceptably low and the method is absolutely free of side effects, there are no objections to the repeated use of immunoscintigraphy which provides important information in primary diagnosis as well as in the follow-up of colorectal cancer patients.

First experiences with the heparin-induced extracorporeal low-density lipoprotein precipitation in the treatment of critical limb ischaemia: a new therapeutical approach?

The heparin-induced extracorporeal low-density lipoprotein (LDL) precipitation (HELP) system is based on the fact that besides lipoproteins even fibrinogen, which seems to be a very important factor in pathogenesis of peripheral arterial disease, is precipitated by high-dose heparin at acid pH values. The elimination of excess fibrinogen and lipoproteins, in particular LDL, leads to a markedly improved microcirculation. The restoration of the latter obviously enabled us to perform limb-saving surgical procedures instead of mutilating amputations. 12 patients suffering from peripheral arterial disease were submitted to 18 HELP treatments in each case instead of having their critically ischaemic legs removed. Surgery could be limited to necrosectomy only and the wounds were either primarily sutured or covered with skin grafts. We were able to avoid 13 amputations in these 12 patients who could finally walk out of the hospital. HELP treatment was free of side effects in all of them.

Abdominopelvic omentopexy: preparatory procedure for radiotherapy in rectal cancer

Adjuvant radiotherapy (RT) in adenocarcinoma of the rectum requires the application of between 5,500 and 6,600 cGy, while the small bowel does not tolerate doses beyond 4,200 cGy without developing enteritis, often followed by stenosis, fistulas, or perforation. This has spurred several attempts to form an artificial diaphragm between the abdominal cavity and the true pelvis, but they were all burdened with various sequelae. Thus, we developed a simple technique to retain the small bowel out of the RT target volume. From the greater omentum we form a bag, which houses the intestinal loops. The lower margin of the omentum is attached to the parietal peritoneum of the posterior abdominal wall beyond the promontorium. The lateral edges are sutured to the ascending and descending colon. RT starts immediately after the laparotomy wound has healed. With the help of this abdominopelvic omentopexy, we have performed high-dose RT following tumor resection in 43 patients. RT was free of complications in all of them as far as the small bowel is concerned. Proctitis and/or cystitis occurred in 14 patients.

[The mucosal sliding flap in the treatment of supra and high trans-sphincteric anal fistula]

Since 1989 we have operated upon 28 patients for trans- or suprasphincteric fistula, using the mucosal sliding flap: After injection of a vasoconstrictory agent into the submucosal tissue we sparingly excise the inner opening of the fistula just beyond the dentate line. A mucosal flap is then meticulously dissected and used to cover the lesion in the rectum. The flap prevents fecal bacteria from invading the intrasphincteric portion of the fistula. This portion remains intact, and so does the sphincter apparatus. Then we excise the fistulous tract, proceeding from its external opening towards the sphincter muscle. After a mean follow-up of 8.1 months all 28 patients are free of symptoms. Proctoscopy did not reveal persistent or recurrent fistula in any of them.

Anti-carcinoembryonic antigen immunoscintigraphy (technetium-99m-monoclonal antibody BW 431/26) and serum CEA levels in patients with suspected primary and recurrent colorectal carcinoma

This study comprises a total of 141 patients with suspected primary and recurrent colorectal carcinomas, in whom immunoscintigraphy with 99mTc-Mab BW 431/26 was performed. Whole-body scans were done 5.5 hr and SPECT imaging of the abdominal region was done at 6 and 24 hr postinjection of 1100 MBq 99mTc-labeled Mab (1 mg). In the course of primary tumor identification (n = 65), sensitivity of anti-CEA immunoscintigraphy was 95%, specificity 91%. In the diagnosis of early recurrences (n = 76), immunoscintigraphy was the method of choice to clarify the problem (sensitivity 94%; specificity 86%). Overall sensitivity of immunoscintigraphy in patients with suspected colorectal carcinomas and early recurrences was 95%, specificity 88%. Human anti-mouse antibodies were found in 29% (80% predominantly anti-isotypic, 20% predominantly anti-idiotypic). In contrast to anti-CEA immunoscintigraphy, the results of serum CEA levels were rather disappointing. Only 18 out of the 43 surgically verified primary colorectal carcinomas and 17 out of 32 patients with recurrences showed elevated serum CEA levels. In our clinical experience with this 99mTc-labeled anti-CEA antibody, immunoscintigraphy can play an important role in the identification of early colorectal recurrences and in postoperative colorectal cancer patients it should be performed in cases with unclear transmission computed tomography.

The immunoscintigraphic use of Tc-99m-labelled monoclonal anti-CEA antibodies (BW 431/26) in patients with suspected primary, recurrent and metastatic breast cancer

The discrepancy between serum CEA levels and CEA tissue expression in patients with breast cancer is well known. Whereas immunohistochemistry shows positive CEA expression in 70-90%, the serum CEA levels are often within the normal range. We performed immunoscintigraphy and SPECT with a Tc-99m labelled anti-CEA monoclonal antibody (MAb BW 431/26) in 46 women with suspected breast cancer or recurrence. The results of anti-CEA immunoscintigraphy, mammography, serum CEA levels and immunohistochemistry were evaluated according to the histology of the tumor. Histology verified breast cancer or recurrence (pT1 [n = 7], pT2 [n = 17], pT3 [n = 3], pT4 [n = 3]) in 30 out of 46 patients; benign breast disease such as fibrocystic disease, fibroadenoma, fatty necrosis or chronic mastitis was responsible for suspicious mammographic findings in 16 patients. Immuno-SPECT showed 25 true-positive, 5 false-negative, 11 true-negative and 5 false-positive findings (sensitivity 83%, specificity 69%). Anti-CEA immuno-SPECT of 2 patients with bone metastasis showed all lesions previously detected by bone scintigraphy to be CEA-expressing metastases. In contrast, serum CEA levels were slightly elevated in only 5 out of 30 patients with histologically verified breast cancer (sensitivity 17%). The results of immuno-histochemistry were surprising; tissue CEA expression could be demonstrated in only 5 patients with breast cancer. According to our experiences with this Tc-99m labelled anti-CEA MAb, immuno-SPECT is a suitable additional method for the diagnosis of breast cancer and especially of recurrence. Pre-operative serum CEA levels give no support for the differentiation between benign and malignant breast tumors.

Prednimustine combined with mitoxantrone and 5-fluorouracil for first and second-line chemotherapy in advanced breast cancer

A total of 60 patients with advanced breast cancer were treated with a combination of prednimustine (P: 110 mg/m2, days 1-5), mitoxantrone (M: 12 mg/m2, day 1) and 5-fluorouracil (F: 500 mg/m2, day 1) (PMF). Treatment was repeated every 3 weeks. In all 53 patients were evaluable for response. A total of 12 subjects had failed prior chemotherapy for metastatic disease. In response to PMF treatment we observed 21 partial remissions and 3 complete remissions, amounting to a total response rate of 45%. The median duration of response was 39 weeks, and median survival was 56 weeks. Dose-limiting side effects were leukopenia (40 cases) and thrombocytopenia (11 patients). Nausea and vomiting was experienced by 93% of subjects; in 56% of cases it reached WHO stage II-III. Alopecia occurred in 18% of our patients. Our results suggest that PMF represents an active regimen in the treatment of advanced breast cancer and yields a response rate of 45%. Considering that the majority of our patients had not received prior chemotherapy, the question remains open as to whether a 45% response rate outweighs the observed toxicity.

Differentiation of lymph-node metastases by anti-CEA immunoscintigraphy in a patient with follicular thyroid and breast cancer

Supraclavicular lymph node metastases appeared in a female patient six years after thyroidectomy, radioiodine therapy and external radiation for a follicular thyroid carcinoma and four years after mastectomy and lymphadenectomy for an invasive ductal breast cancer. It was not possible either by conventional imaging methods or by serological methods, to assign the metastases to one of the two primary tumors. Anti-CEA immunoscintigraphy and SPECT of the cervicothoracic region showed a circumscribed pathological uptake of 99mTc-labeled anti-CEA antibodies in the area of the supraclavicular lymph nodes. The preoperative suspicion of lymph-node infiltration by CEA-expressing breast cancer cells was confirmed histologically after surgical removal of the lymph nodes.

Differentiation of Lymph-Node Metastases by Anti-CEA Immunoscintigraphy in a Patient with Follicular Thyroid and Breast Cancer

Supraclavicular lymph node metastases appeared in a female patient six years after thyroidectomy, radioiodine therapy and external radiation for a follicular thyroid carcinoma and four years after mastectomy and lymphadenectomy for an invasive ductal breast cancer. It was not possible either by conventional imaging methods or by serological methods, to assign the metastases to one of the two primary tumors. Anti-CEA immunoscintigraphy and SPECT of the cervicothoracic region showed a circumscribed pathological uptake of 99mTc-labeled anti-CEA antibodies in the area of the supraclavicular lymph nodes. The preoperative suspicion of lymph-node infiltration by CEA-expressing breast cancer cells was confirmed histologically after surgical removal of the lymph nodes.

99mTc-labeled monoclonal anti-carcinoembryonic antigen antibody (BW 431/26). Clinical results in the detection of colorectal carcinomas and recurrences

With the introduction of 99mTc-labeled monoclonal antibodies against carcinoembryonic antigen (CEA) a clinically relevant extension can be expected in the diagnosis of colorectal tumors by immunoscintigraphy (IS). This study comprises a total of 49 patients (primary colorectal tumors, occult neoplasms, and suspicious recurrences), in whom IS with 99mTc monoclonal antibody (MAb) BW 431/26 was performed. After injection of 1100 MBq 99mTc MAb BW 431/26 a whole-body scan was performed in anterior and posterior projection 5 1/2 h later, and SPECT of the abdominal region was done after 6 and 24 h. In the course of primary tumor identification (n = 20) all coloscopically diagnosed and operatively verified carcinomas were confirmed and correctly localized by IS (n = 11). In three patients with positive IS and suspicious coloscopic findings surgery was refused by patients and relatives. In five cases IS was true negative and in 1 case false positive. In the diagnosis of recurrences (n = 29) IS showed an uptake in computer-tomographically and coloscopically suspicious areas in 17 cases. In 12 cases IS was rated negative (11 true-negative findings in scar and granulation tissue, 1 false-negative finding in para-aortal lymph nodes). Elevated serum CEA levels were found only in 17 of 31 patients with true-positive IS. In postoperative cancer care IS with 99mTc-labeled anti-CEA antibody plays a preeminent role in the exclusion or identification of colorectal recurrences.

Anatomical bases for a safe method of subclavian venipuncture. Clinical experience in 350 cases

Based on fundamental anatomical considerations which are explained in detail we developed a safe technique for the catheterization of the subclavian v.: the point of puncture, which is situated about 25 mm below the junction between the medial and the middle thirds of the clavicle, is accurately determined with the help of a pattern described in the paper. The needle is directed towards the palpable dimple between the spinous processes of the 6th and the 7th cervical vertebrae. The only structure the cannula can reach is the medial portion of the subclavian v. into which the catheter is inserted. Therefore pneumothorax, haemothorax or other incidents do not occur. The method was tested in 350 cases and proved to be absolutely free of complications.