Dosimetrische Verifikation von MammoSite-Bestrahlungsplänen mit Monte-Carlo-Simulationen sowie Messungen mit einem 2D-Ionisationskammer-Array

The surgical removal of a breast tumour is often followed by postoperative irradiation of the surrounding tissue with a radioactive source (brachytherapy). When performing the MammoSite procedure, a spherical silicone balloon is inserted and filled with a NaCl solution. In a period of about five days in several sessions an iridium-192 source with high activity travels through a catheter into the balloon (afterloading) to irradiate the tumour cells remaining in the cavity. In this study, dose distributions of a MammoSite applicator are investigated based on measurements with a 2D detector array, Monte Carlo simulations and calculations with BrachyVision. The focus is set on the 2D detector array and its possible application in the verification process in 3D brachytherapy treatment planning. The measured dose distributions conform well to the doses of BrachyVision with deviations of less than 5% within the clinically relevant field range. The deviations of the measured and calculated distributions from the simulation results are below 3%. The 2D detector array allows a new verification method for MammoSite treatment plans with sufficient accuracy. Future verifications can be performed without additional Monte Carlo simulations.     

Molecular body imaging: MR imaging, CT, and US. Part II. Applications

Molecular imaging is expected to have a major impact on the early diagnosis of diseases and disease monitoring in the next decade. Traditionally, nuclear imaging techniques have been the mainstay of molecular imaging in the clinical arena. However, with continued development of molecularly targeted contrast agents for nonnuclear imaging techniques such as magnetic resonance (MR), computed tomography (CT), and ultrasonography (US), the spectrum of clinical molecular imaging applications is expanding. In the second part of this review series, an overview of applications of molecular MR imaging-, CT-, and US-based imaging strategies that show promise for clinical translation is presented, and key challenges that need to be addressed to successfully translate these promising techniques in the future are discussed. ? RSNA, 2012.     

Differential regulation of gliogenesis in the context of adult hippocampal neurogenesis in mice

In adult hippocampal neurogenesis, new neurons appear to originate from a cell with astrocytic properties expressing glial fibrillary acidic protein (GFAP). Also, new astrocytes are generated in the adult dentate gyrus. Whereas the putative astrocyte-like progenitor cells are consistently S-100beta-negative, many new astrocytes are S-100beta-positive. Thus, it is unclear whether the GFAP-positive progenitor cells are astrocytes in a general sense or rather neural progenitor cells with certain astrocytic characteristics. We therefore investigated the development of GFAP-expressing cells in the context of adult hippocampal neurogenesis. Proliferating cells could be either GFAP-positive or doublecortin-positive (DCX), but never both, indicating two independent populations of dividing cells in the glial and neuronal lineages. Two distinct populations of cells with astroglial properties were detected-one expressing GFAP, the other co-expressing GFAP and S-100beta. We never found S-100beta-cells to be in S-phase. No overlap between neuronal and glial markers was seen at any time point. Thus, astrogenesis occurred in parallel and to some degree independent of adult neurogenesis. The uninterrupted GFAP expression in this lineage, and neuronal markers in the other lineage, argue against a late common precursor for neurogenesis and gliogenesis in the adult hippocampus. Very few newly generated microglia and no new oligodendrocytes were detected. Environmental enrichment and voluntary wheel running-two experimental paradigms with robust stimulatory effects on adult hippocampal neurogenesis-affected hippocampal astrogenesis differentially: Running, but not enrichment, strongly induced net astrogenesis (GFAP/S-100beta), but also GFAP-positive S-100beta-negative cells, which thus appear to be a transiently amplifiable intermediate population within the glial lineage.     

Oral vinorelbine and cisplatin with concomitant radiotherapy in stage III non-small cell lung cancer (NSCLC): a feasibility study

BACKGROUND: Concurrent chemoradiotherapy has improved survival in inoperable stage III non-small cell lung cancer (NSCLC). This phase I trial was performed in order to establish a dose recommendation for oral vinorelbine in combination with cisplatin and simultaneous radiotherapy. PATIENTS AND METHODS: Previously untreated patients with stage IIIB NSCLC received concurrent chemoradiotherapy with 66 Gy and 2 cycles of cisplatin and oral vinorelbine which was administered at 3 different levels (40, 50 and 60 mg/m2). This was to be followed by 2 cycles of cisplatin/ vinorelbine oral consolidation chemotherapy. The study goal was to determine the maximal recommended dose of oral vinorelbine during concurrent treatment. RESULTS: 11 stage IIIB patients were entered into the study. The median radiotherapy dose was 66 Gy. Grade 3-4 toxicity included neutropenia, esophagitis, gastritis and febrile neutropenia. The dose-limiting toxicity for concurrent chemoradiotherapy was esophagitis. 9 patients received consolidation chemotherapy, with neutropenia and anemia/thrombocytopenia grade 3 being the only toxicities. The overall response was 73%. CONCLUSION: Oral vinorelbine 50 mg/m2 (days 1, 8, 15 over 4 weeks) in combination with cisplatin 20 mg/m2 (days 1-4) is the recommended dose in combination with radiotherapy (66 Gy) and will be used for concurrent chemoradiotherapy in a forthcoming phase III trial testing the efficacy of consolidation chemotherapy in patients not progressing after chemoradiotherapy.     

The role of maternal nutrition,metabolic function and the placenta in developmental programming of renal dysfunction

The intrauterine environment is critical for the development of the foetus. Barker and colleagues were the first to identify that adverse perturbations during foetal development are associated with an increased risk of developing diseases in adulthood, including cardiorenal disease. Specifically for the kidney, perturbations in utero can lead to nephron deficits and renal dysfunction by a number of mechanisms. Altered programming of nephron number is associated with an increased risk of developing kidney disease via glomerular hypertrophy and reduced vasodilative capacity of the renal blood vessels; both of which would contribute to hypertension in adulthood, with males being more susceptible to disease outcomes. Additionally, alterations in the renin‐angiotensin system (RAS) such as an upregulation or downregulation of specific receptors, depending on the nature of the insult, have also been implicated in the development of renal dysfunction. Sex‐specific differences in the expression of the RAS during late gestation and in the early postnatal environment have also been identified. Extensive research has demonstrated that both uteroplacental insufficiency and maternal malnutrition alter renal development in utero. Equally, exposure to maternal diabetes and maternal obesity during development are also associated with an increased risk of developing renal disease, however, the mechanism behind this association is poorly understood. Therefore, identifying the link between an adverse intrauterine environment and the programmed kidney disease risk in adulthood may facilitate the development of strategies to alleviate the epidemics of cardiorenal disease worldwide, in addition to understanding why males are more susceptible to adult‐onset cardiovascular diseases.     

Strahlentherapie des nicht-kleinzelligen Lungenkarzinoms

Traditionally, radiotherapy has been a mainstay in the treatment of non-small cell lung cancer (NSCLC) particularly in the locally advanced stages IIIa and IIIb. Recently published data from studies confirmed the role of concurrent chemoradiotherapy as the standard treatment of these locally advanced tumors. Results could be improved further by modern radiotherapy techniques; however, the limitations of this concept under the current technical circumstances could also be recognized. In the future, advances could be achieved by inclusion of information on metabolic characteristics of tumors in radiotherapy planning (such as hypoxia) or by combination with novel modalities, e.?g. immunotherapy; however, currently these concepts are predominantly still in the stage of clinical research. In contrast, progress has been made concerning the utilization of stereotactic ablative radiotherapy. Formerly, unfortunately often regarded by many as a niche technology, stereotactic body radiotherapy has evolved not only into a routine clinical option for inoperable patients but also into an alternative treatment option probably equivalent to surgery. Furthermore, stereotactic ablative body radiotherapy is emerging as an important component of multimodal treatment concepts in metastatic stages. This article gives an overview of recent advances, current standards and emerging developments in the radiotherapy of NSCLC.     

Cardiac arrest caused by acute intoxication—insight from a registry

IntroductionThe aim of the study was to evaluate the epidemiology and outcome after cardiac arrest caused by intoxication.MethodsA retrospective analysis of 1991 to 2010 medical record of patients experiencing cardiac arrest caused by self-inflicted, intentional intoxication was performed. The setting was an emergency department of a tertiary care university hospital. The primary end point was the presentation of epidemiologic data in relation to favorable neurologic outcome, defined as cerebral performance categories 1 or 2 and 180-day survival. Furthermore, the patients were subdivided into a single-substance and polysubstance group, depending on the substances causing the intoxication.ResultsOf 3644 patients admitted to our department, 99 (2.7%) with a median age of 26 (interquartile range, 19-42) years (37% female) were included. Cardiac arrest was witnessed in 62 cases (63%). Eleven patients (11%) received basic life support by bystanders, and 11 (11%) had a shockable rhythm in the initial electrocardiogram. The combined end point “good survival” was achieved by 34 patients (34%). Cardiac arrest occurred out of hospital in 73 patients (74%) and in-hospital in 26 patients (26%). A single substance causing the intoxication was found in 56 patients (56%). Opiates were the leading substance, with 25 patients (25%) using them.ConclusionCardiac arrest caused by intoxication is found predominately in young patients. Overall, favorable neurologic survival was achieved in 34%. Opiate-related cardiac arrest was associated with poor survival and a high incidence of neurologic deficits.     

100 cc 3% sodium chloride bolus: a novel treatment for hyponatremic encephalopathy

Hyponatremic encephalopathy is a potentially lethal condition with numerous reports of death or permanent neurological injury. The optimal treatment for hyponatremic encephalopathy remains controversial. We have introduced a unified approach to the treatment of hyponatremic encephalopathy which uses 3% NaCl (513 mEq/L) bolus therapy. Any patient with suspected hyponatremic encephalopathy should receive a 2 cc/kg bolus of 3% NaCl with a maximum of 100 cc, which could be repeated 1–2 times if symptoms persist. The approach results in a controlled and immediate rise in serum sodium with little risk of inadvertent overcorrection.     

High prevalence of antibodies against polyomavirus WU,polyomavirus KI,and human bocavirus in German blood donors

Background  

DNA of the polyomaviruses WU (WUPyV) and KI (KIPyV) and of human bocavirus (HBoV) has been detected with varying frequency in respiratory tract samples of children. However, only little is known about the humoral immune response against these viruses. Our aim was to establish virus-specific serological assays and to determine the prevalence of immunoglobulin G (IgG) against these three viruses in the general population.     

Radial oxygen gradients over rat cortex arterioles

Purpose  

We present the results of the visualisation of radial oxygen gradients in rats’ cortices and their potential use in neurocritical management.