[Tumor-to-tumor: a wolf in sheep's clothing]. / Tumor-to-tumor: un lobo disfrazado de cordero.

TITLE: Tumor-to-tumor: un lobo disfrazado de cordero.

Long-term distribution and migration of 137Cs in a small lake ecosystem with organic-rich catchment: A case study of Lake Vorsee (Southern Germany).

In the shallow eutrophic Lake Vorsee with an organic-rich catchment the 137Cs activity concentration in water samples (n = 250) and different fish species (n = 631) was determined for a period of 30 years starting soon after the Chernobyl fallout. To understand the distribution and migration of 137Cs in the ecosystem of Lake Vorsee, also the 137Cs inventory in soils of the catchment area, in sediments, in suspended matter, in water plants, as well as its vertical distribution in soils and sediments were studied. The time dependency of the 137Cs activity concentration in water and fish was modelled with a compartment model (AQUASCOPE) as well as with the sum of two exponential functions. Results for effective half-lives of 137Cs in water are Teff1  = 1.2 a and Teff2  = 7.2 a; for small cyprinidae Teff1  = 0.6 a and Teff2  = 8.9 a; and for pike Teff1  = 1.4 a and Teff2  = 12.1 a. The vertical distribution of 137Cs activity concentration in soils was described by a partial differential equation (diffusion constant D = (1.05 ±â€¯1.16) cm2⋅a-1 and convection speed v = (0.14 ±â€¯0.07) cm⋅a-1) and its distribution in sediments by a system of two coupled partial differential equations (fixation rate f = 2.0 d-1; distribution coefficient Kdex = (543 ±â€¯140) L⋅kg-1; sedimentation rate RS = (0.030 ±â€¯0.010) g⋅(cm2⋅a)-1; bioturbation constant Dbio, decreasing linearly with depth with Dbioabs = (3.3 ±â€¯1.0) cm2⋅a-1 at the surface). According to the extended AQUASCOPE model, the following fractions of the total 137Cs inventory were found in the different compartments of the lake ecosystem in 2016: 9.0⋅10-1 in soils of the catchment area, 1.0⋅10-1 in sediments, 5.5⋅10-5 in water, 1.5⋅10-5 in suspended matter, 1.3⋅10-5 in watermilfoil, and 1.6⋅10-6 in fish.

Classification of cerebral arteriovenous malformations and intranidal flow patterns by color-encoded 4D-hybrid-MRA.

BACKGROUND AND PURPOSE: 4D MRA has been evolving as a noninvasive supplement for DSA. The purpose of this study was to evaluate the feasibility of a newly developed blood flow visualization technique for the classification of cerebral AVMs. We hypothesized that 4D-hMRA allows detection of different flow patterns within the nidus as well as differentiation of feeders and draining veins and has very good agreement with DSA regarding the Spetzler-Martin grade. MATERIALS AND METHODS: Thirty-one consecutive patients with AVMs were evaluated by using 4D-hMRA and DSA by 2 blinded raters. Rating criteria included Spetzler-Martin score and other morphologic variables together with a new scale for 3 intranidal flow patterns (homogeneous = 1, unidirectional = 2, heterogeneous = 3). RESULTS: The Spetzler-Martin grades were rated different from DSA in 5 cases by rater 1 and in 3 cases by rater 2 with an excellent interrater reliability of κ = 0.96 (4/31, 1 by size and 3 by drainage). Each reader missed 5 feeders on 4D-hMRA. Draining veins were distinguished in the temporal course in 7 on DSA but in 8 and 12 on 4D-hybrid-MRA (raters 1 and 2 respectively), with κ = 0.79. A type 1 intranidal flow pattern was recognizable in 9 (30%) patients; type 2, in 19 (60%); and type 3, in 3 (10%). CONCLUSIONS: 4D-hMRA allows reliable Spetzler-Martin grading and detection of brain arteriovenous malformation feeding arteries and draining veins, with the drawback that for small vessels DSA is still needed. Draining veins might even be detected with higher sensitivity than on DSA. Discrimination of different intranidal flow patterns is possible, but their relevance for hemorrhage risk assessment and therapy planning requires further study.

Intracranial aneurysms in childhood: report of 8 cases and review of the literature.

OBJECTIVE: Subarachnoid haemorrhage (SAH) due to ruptured cerebral aneurysms is a rare diagnosis in childhood and is believed to differ from that in adults with regard to sex, aneurysm size and location, clinical appearance as well as outcome, suggesting that aneurysms in childhood are a distinct entity. PATIENTS AND METHODS: Seven children and young adults with a mean age of 13.6 years suffered from aneurysmal subarachnoid haemorrhage. On admission two patients were Hunt & Hess (HH) grade I, four were grade III and one was grade V. In addition, there was one 14-year-old boy who presented with seizures and was found to have a non-ruptured aneurysm of the basilar tip. Overall, there were two female and six male patients. Anterior circulation aneurysms were diagnosed in five patients whereas three patients suffered from posterior circulation aneurysm. Five large (10-25 mm) aneurysms and three smaller than 10 mm were found. Surgical clipping of the aneurysms was performed in all patients. RESULTS: Six patients showed no significant disability or no symptoms at all when evaluated with the modified Rankin Scale (mRS 0 or 1). One patient suffered from persisting nerve palsies (mRS 2) and one 6-year-old boy, admitted with HH grade V, died due to the initial poor clinical condition followed by severe brain oedema and secondary complications. CONCLUSIONS: Reviewing the literature, a male predominance, low rate of SAH, high percentage of complex aneurysms and of aneurysms located in the posterior circulation are characteristic features of aneurysms in childhood. Once a cerebral aneurysm is diagnosed in the younger age group, definite therapy should be performed soon as the outcome is expected to be more favourable than in adulthood.

Sjögren's syndrome of the parotid gland: value of diffusion-weighted echo-planar MRI for diagnosis at an early stage based on MR sialography grading in comparison with healthy volunteers.

PURPOSE: To investigate the value of diffusion-weighted echo-planar imaging (DW-EPI) for quantifying functional changes of the parotid gland in Sjögren's disease and to evaluate whether ADC mapping allows for early diagnosis based on MR sialography grading. MATERIALS AND METHODS: Using a DW-EPI sequence at 1.5 T (b-factors: 0, 500 and 1000 sec/mm (2)), the parotid glands of 52 healthy volunteers and 13 patients with histologically verified affection of Sjögren's disease were examined. All scans were performed prior to and following gustatory stimulation with 5 ml of lemon juice. ADC maps were evaluated by placing an inordinate region-of-interest (ROI) enclosing the entire parotid gland. Sjögren's disease was graded based on MR sialography findings using a 4-point grading-scale. Statistics included student t-test and kappa-analysis. RESULTS: In healthy volunteers mean ADCs of 1.14 x 10 (-3 )mm (2) /sec before and 1.2 x 10 (-3) mm (2) /sec after stimulation were observed. Higher ADCs were determined for early-stage Sjögren's disease, averaging 1.22 x 10 (-3) mm (2) /sec before and 1.29 x 10 (-3) mm (2) /sec after stimulation. Advanced disease revealed significantly lower ADCs (0.97 x 10 (-3) mm (2) /sec (p = 0.002) before and 1.01 x 10 (-3) mm (2) /sec (p < 0.001) after stimulation). CONCLUSION: DW-EPI seems to display functional changes of the parotid gland affected by Sjögren's disease. Combined with MR sialography, it might be a useful tool for discriminating healthy from affected glands and seems to allow differentiation between the early and advanced disease.

Value of apparent diffusion coefficient calculation before and after gustatory stimulation in the diagnosis of acute or chronic parotitis.

The purpose of the study was to investigate the value of diffusion-weighted (DW) echo-planar imaging (EPI) for quantifying physiological changes of the parotid gland before and after gustatory stimulation in patients suffering from acute or chronic recurrent inflammation in comparison with healthy volunteers. Using a DW-EPI sequence at 1.5 T, parotid glands of 19 consecutive patients with acute (n=14) and chronic (n=5) inflammation of parotid glands and 52 healthy volunteers were examined. Magnetic-resonance (MR) images were obtained before and after gustatory stimulation with 5 cc of lemon juice. In volunteers mean ADC values of 1.14 x 10(-3) mm(2)/s before and 1.2 x 10(-3) mm(2)/s after gustatory stimulation were observed. In acute inflammation ADC values were higher before [1.22 x 10(-3) mm(2)/s (p=0.006)] and after stimulation [1.32 x 10(-3) mm(2)/s (p<0.001)]. Before stimulation ADC differences between chronic inflammation (1.05 x 10(-3) mm(2)/s) and healthy volunteers (p=0.04) as well as between acute and chronic inflammation (p=0.005) were statistically significant. No differences were detected after stimulation between chronic inflammation (1.2 x 10(-3) mm(2)/s) and healthy volunteers (p=0.94) and between acute and chronic inflammation (p=0.15), respectively. DW-EPI seems to display the physiological changes of the parotid gland in patients suffering from acute or chronic inflammation and might be useful for discriminating healthy from affected glands.

Long-term follow-up of cerebral aneurysms after endovascular therapy prediction and outcome of retreatment.

BACKGROUND AND PURPOSE: The purpose of this study was to analyze angiographic and clinical results before and after additional endovascular therapy in patients with previously coiled but reopened cerebral aneurysms and to identify possible risk factors for retreatment of an aneurysm. MATERIALS AND METHODS: Follow-up with selective digital subtraction angiography was performed in 323/596 (54.2%) patients harboring 342 aneurysms with a mean follow-up time of 28.6 months. The patients were divided into 3 groups: group A, who remained stable after initial treatment; group B, who showed minor morphologic changes; and group C, who underwent repeat treatment. Univariate and multivariate regression analyses were performed to determine possible risk factors for aneurysmal retreatment. RESULTS: Single or multiple retreatment was performed in 33 of 323 (10.2%) patients. Retreatment of small aneurysms (< or =10 mm) with small necks (< or =4 mm) was performed in 6 of 214 aneurysms. When summarizing all other aneurysms as a "risk group" (n = 128), the odds ratio (OR) for retreatment in the "risk group" was 3.11 (95% CI: 1.43-6.75; P = .004). In patients with residual aneurysm after the first treatment, OR for retreatment was 3.96 (95% CI: 1.48-10.65; P = .006), whereas a neck remnant, clinical presentation, and aneurysmal localization were not predictive. We observed no resulting morbidity and mortality from the 33 retreatment procedures. CONCLUSION: In our series, the retreatment of aneurysmal recurrences was a safe procedure. The best single predictors of aneurysmal recurrence were aneurysmal anatomy (neck width >4 mm and diameter >10 mm) and the presence of a residual aneurysm after initial treatment. A limitation in our study was the significant number of patients lost to follow-up (22.7%).

[MR sialography: evaluation of an ultra-fast sequence in consideration of a parallel acquisition technique and different functional conditions in patients with salivary gland diseases]. / MR-Sialographie: Prospektive Evaluation ultraschneller Sequenzen mit paralleler Bildgebung und oraler Stimulation bei Patienten.

PURPOSE: To evaluate an ultra-fast sequence for MR sialography requiring no post-processing and to compare the acquisition technique regarding the effect of oral stimulation with a parallel acquisition technique in patients with salivary gland diseases. MATERIALS AND METHODS: 128 patients with salivary gland disease were prospectively examined using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and a maximum slew rate of 125 mT/m/sec. A single-shot turbo-spin-echo sequence (ss-TSE) with an acquisition time of 2.8 sec was used in transverse and oblique sagittal orientation. All images were obtained with and without a parallel imaging technique. The evaluation of the ductal system of the parotid and submandibular gland was performed using a visual scale of 1-5 for each side. The images were assessed by two independent experienced radiologists. An ANOVA with post-hoc comparisons and an overall two tailed significance level of p = 0.05 was used for the statistical evaluation. An intraclass correlation was computed to evaluate interobserver variability and a correlation of > 0.8 was determined, thereby indicating a high correlation. RESULTS: Depending on the diagnosed diseases and the absence of abruption of the ducts, all parts of excretory ducts were able to be visualized in all patients using the developed technique with an overall rating for all ducts of 2.70 (SD +/- 0.89). A high correlation was achieved between the two observers with an intraclass correlation of 0.73. Oral application of a sialogogum improved the visibility of excretory ducts significantly (p < 0.001). In contrast, the use of a parallel imaging technique led to a significant decrease in image quality (p = 0,011). CONCLUSION: The applied ss-TSE for MR sialography allows fast and sufficient visualization of the excretory ducts of the main salivary glands in patients, and no elaborate post-processing is required. Use of an oral sialogogum is suggested to improve the results of MR sialography.

[16-Row multidetector CT of the pelvis after iliosacrally inserted osteosynthetic screws: experimental study of dose adjustment on preserved human cadaver specimens]. / 16-Zeilen-Spiral-CT des knöchernen Beckens nach Schraubenosteosynthese der iliosakralen Gelenke--Untersuchungen zur Dosisanpassung in einem Ex-vivo-Modell.

PURPOSE: The study was performed to assess the necessity of dose adjustment (kV or mAs (eff.)) in 16-slice CT (MDCT) in postoperative controls of iliosacrally inserted osteosynthetic screws (OS) on preserved human cadaver specimens. The minimal tube settings for diagnostic imaging of the pelvic bone were analyzed and the effective doses and important organ doses were calculated. MATERIALS AND METHODS: 16 preserved human cadaver specimens with transiliac osteosynthetic screws were scanned on a 16-slice CT (collimation 16 x 0.75 mm, pitch 0.7) with 10 different tube settings (35, 50, 75, 100, 150 mAs (eff.) and 120 and 140 kV). 32 datasets (blinded for name and scan parameters) with and without OS were independently evaluated by four observers. The 10 series were sorted by subjective image quality (image noise, contours, artifacts), and the series with the lowest but still diagnostic quality was selected. The statistical analysis included multi-rater-kappa-test and Wilcoxon test for paired samples. RESULTS: The multi-reader agreements for sorting the series were fair (kappa = 0.38). The agreements in comparing the lowest diagnostic image qualities were slight to fair (kappa = 0.08-0.23). The paired sample test comparing the lowest diagnostic image quality with and without OS showed no statistical significance (p = 0.29). 87.5 % of the readouts (n = 64 [16 examinations, 4 readers]) with OS and 78.1 % of those without OS could be adequately diagnosed using the three series with the lowest effective doses (0.9-1.4 mSv for men, 1.4-2.0 mSv for women; 120 kV-35 mAs (eff.), 120-50, 140-35). CONCLUSION: MSCT scans of the pelvic bone can be performed with very low effective doses. It is not necessary to adjust tube settings when imaging bones with osteosynthetic screws. If the concept for the control of the pelvic osteosynthetic screw position includes more than 2 conventional films (for example anterioposterior view with additional inlet and outlet views), a low dose CT is preferable to conventional radiography.

Angiographic follow-up of vertebrobasilar artery aneurysms treated with detachable coils.

Endovascular treatment of ruptured vertebrobasilar artery aneurysms with Gugliemi detachable coils (GDC) has become an alternative to surgery. Mid-term angiographic follow-up can now be reported. Of 111 vertebrobasilar aneurysms in 110 patients we treated with GDC since 1992, 53 underwent angiography within 1 year and 59 after more than 18 months. We did not achieve complete occlusion on initial treatment of 23 aneurysms (21%). Complications were observed in 19 patients (17%), leading to permanent clinical disability in eight. Enlargement of the neck or reopening was seen in 12 (23%) of 53 aneurysms followed by angiography within 12 months. Documented recanalisation was treated in four (8%). Angiography was performed after 18-78 months in 59 patients, of whom nine, including three with initially incomplete occlusions, were retreated with GDC. Within the entire second observation period, three (5%) of the 59 patients had a further haemorrhage and were retreated with GDC. Rebleeding proved to be the only factor influencing the clinical outcome of retreated patients.

Parity violation in proton-proton scattering at 221 MeV.

The parity-violating longitudinal analyzing power, A(z), has been measured in pvectorp elastic scattering at an incident proton energy of 221 MeV. The result obtained is A(z) = [0.84+/-0.29(stat)+/-0.17(syst)]x10(-7). This experiment is unique in that it selects a single parity violating transition amplitude (3P2 - 1D2) and consequently directly constrains the weak meson-nucleon coupling constant h(pp)(rho). When this result is taken together with the existing pvectorp parity violation data, the weak meson-nucleon coupling constants h(pp)(rho) and h(pp)(omega) can, for the first time, both be determined.

A generic method for the production of cell lines expressing high levels of 7-transmembrane receptors.

G-protein-coupled or 7-transmembrane receptors (7TMRs) are often studied after heterologous expression in mammalian cells such as COS-7, CHO-K1, or HEK-293s. In this paper, we describe the development of a rapid and generic method for producing stable Chinese hamster ovary cell lines expressing high levels of recombinant 7TMRs by N-terminal tagging these proteins with the hemagglutinin (HA) sequence. To illustrate the broad applicability of this technique, we have presented data from cell lines expressing a glycoprotein hormone receptor for follicle-stimulating hormone (FSHR), CXC- (CXCR-2), and CC-chemokine (CCR-1) receptors and peptide receptors from the somatostatin (SSTR1, 2, 5) and neuropeptide Y (NPY-Y2, -Y4 Rs) families. Typically, cell lines with a receptor density of 1 to 15 pmol/mg protein are produced with this method. The presence of the HA tag does not adversely affect the binding or functional activity of the receptors.

[PTCA in the acute state of myocardial infarct: hospital course of 785 consecutive patients]. / PTCA im Stadium des akuten Myokardinfarktes: Hospitalverlauf von 785 konsekutiven Patienten.

Rapid reperfusion of the occluded coronary artery is essential for the reduction of mortality and complications of acute myocardial infarctions. Intravenous thrombolytic therapy using various thrombolytic substances has proven to be effective and easy to perform and has gained widespread acceptance for treatment of acute myocardial infarction. Because of several contraindications, as well as failure to achieve patency of the infarcted vessel in 25-30% of patients, severe bleeding complications, a time interval of 6 or more hours after suspected onset of myocardial infarction, and a high rate of recurrent ischemia, this treatment is currently limited to a small percentage of patients with acute myocardial infarction. Immediate percutaneous transluminal coronary angioplasty (PTCA) can be applied to nearly every patient presenting with acute myocardial infarction. Therefore, we offer immediate PTCA as the primary treatment to all of our patients presenting with acute myocardial infarction. Between January 1987 and December 1991, immediate PTCA was performed in 785 of 903 (87%) consecutive patients (aged 23-86 years, mean 61 +/- 10). 82% (640/785) of the patients were men. Anterior myocardial infarction was present in 372 patients (47%), inferior infarction in 413 patients (53%). 245 patients (31%) had 1-vessel disease, 221 patients (28%) two-vessel disease and 319 patients (41%) had three-vessel disease. 97 patients (12%) were in cardiogenic shock. In 675/785 patients (86%) the infarct related vessel was occluded (TIMI < or = 1). 86% of patients had a patent infarct related vessel (TIMI > or = 2) leaving the catheterization laboratory. The overall in-hospital mortality was 6.9% (54/785 patients), after exclusion of high-risk patients (age > 75 years, cardiogenic shock, PTCA under cardiopulmonary resuscitation) mortality decreased to 2.5%. Recurrent ischemia necessitated immediate repeat PTCA in 4.4% of the patients, in 8.1% of patients another elective PTCA was performed during hospitalization and 9.7% of patients were sent to surgery (4.0% on an emergency basis). 87% of all patients presenting with acute myocardial infarction could be treated successfully with immediate PTCA. With respect to the severely ill group of patients the primary success rate is high, the rate of reocclusion is low, and the overall mortality is extremely low. From our data, it is obvious that immediate PTCA compared to thrombolytic therapy is the superior treatment of myocardial infarction.

Detection of osteoporotic sacral fractures with radionuclides.

Osteoporotic sacral fractures usually occur in elderly patients as a result of mild trauma. Clinical symptoms range from localized sacral tenderness to neurologic problems attributable to sacral nerve root irritation or cauda equina compression. Although the radiographic diagnosis is difficult to establish, bone scans show a characteristic H-shaped pattern of radionuclide uptake across the sacrum and sacroiliac joints. Four cases of osteoporotic sacral fracture with confirmation by computed tomography are included in this report.