Association of Diabetes and Dental Caries Among U.S. Adolescents in the NHANES Dataset

Purpose: To investigate the association of diabetes and dental caries in U.S. adolescents in the National Health and Nutrition Examination Survey (NHANES). Methods: NHANES 2005 to 2010 data represented 24.38 million U.S. adolescents. Outcome variables were dental-caries-experience and untreated dental decay. Analyses included descriptive statistics and logistic regressions. Multivariable models controlling for known common confounding variables using weighted estimates for odds ratios (ORs) and 95% confidence intervals (CI). Results: Diabetes and prediabetes prevalence were 0.35 percent and 12.8 percent, respectively. Subjects with increased blood glucose and HbA1C had significantly greater dental caries (78.9 percent versus 56.3 percent) and (83.2 percent versus 56.2 percent, P<0.001) when compared to those with normal values. Fully adjusted models revealed that diabetic adolescents were more than twice as likely to experience dental caries compared to nondiabetic adolescents (OR=2.43, CI=2.39 to 2.47). Similarly, diabetic individuals were more likely to have untreated dental decay than non-diabetics (OR=3.37, CI=3.32 to 3.42). Conclusion: Diabetic adolescents, compared to nondiabetics, had higher odds of dental caries experience and untreated dental decay after controlling for age, race/ethnicity, gender, body mass index, family income-to-poverty ratio, and country of birth. This study highlights the need for continued interprofessional collaboration to address oral health in prediabetic and diabetic adolescents.

Detection of extraneous water ingress into the sewer system using tandem methods - a case study in Trondheim city

Infiltration and inflow (I/I) of extraneous water in separate sewer systems are serious concerns in urban water management for their environmental, social and economic consequences. Effective reduction of I/I requires knowing where excess water ingress and illicit connections are located. The present study focuses on I/I detection in the foul sewer network of a catchment in Trondheim, Norway, during a period without snowmelt or groundwater infiltration. Fiber-optic distributed temperature sensing (DTS) was used for the first time in Norway to detect I/I sources in tandem with closed-circuit television inspection (CCTV) and smoke testing. DTS was an accurate and feasible method for I/I detection, though it cannot identify exact types of failure and sources of I/I. Therefore, other complementary methods must be used, e.g. CCTV or smoke testing. However, CCTV was not completely useful in confirming the DTS results. This study provides practical insights for the rehabilitation and repair of sewer networks that suffer from the undesirable I/I of extraneous water.

The EANM practice guidelines for bone scintigraphy

PURPOSE

The radionuclide bone scan is the cornerstone of skeletal nuclear medicine imaging. Bone scintigraphy is a highly sensitive diagnostic nuclear medicine imaging technique that uses a radiotracer to evaluate the distribution of active bone formation in the skeleton related to malignant and benign disease, as well as physiological processes.

METHODS

The European Association of Nuclear Medicine (EANM) has written and approved these guidelines to promote the use of nuclear medicine procedures of high quality.

CONCLUSION

The present guidelines offer assistance to nuclear medicine practitioners in optimizing the diagnostic procedure and interpreting bone scintigraphy. These guidelines describe the protocols that are currently accepted and used routinely, but do not include all existing procedures. They should therefore not be taken as exclusive of other nuclear medicine modalities that can be used to obtain comparable results. It is important to remember that the resources and facilities available for patient care may vary.

Modeling Current Density Maps Using Aliev-Panfilov Electrophysiological Heart Model

Most existing studies of cardiac arrhythmia rely on surface measurements through optical or electrical mapping techniques. Current density imaging (CDI) is a method which enables us to study current pathways inside the tissue. However, this method entails implementation complexities for beating ex vivo hearts. Hence, this work presents an approach to simulate and study the current distributions in different cardiac electrophysiological states. The results are corroborated by experimental data, and they indicate that different states were distinguishable. The CDI simulations can be used for studying cardiac arrhythmias under simulation conditions which are otherwise impossible or difficult to be implemented experimentally.

32nd International Austrian Winter Symposium : Zell am See, the Netherlands. 20-23 January 2016

A1 68Ga-PSMA PET/CT in staging and restaging of Prostate Cancer Patients: comparative study with 18F-Choline PET/CT

W Langsteger, A Rezaee, W Loidl, HS Geinitz, F Fitz, M Steinmair, G Broinger, L Pallwien-Prettner, M Beheshti

A2 F18 Choline PET – CT: an accurate diagnostic tool for the detection of parathyroid adenoma?

L Imamovic, M Beheshti, G Rendl, D Hackl, O Tsybrovsky, M Steinmair, K Emmanuel, F Moinfar, C Pirich, W Langsteger

A3 [18F]Fluoro-DOPA-PET/CT in the primary diagnosis of medullary thyroid carcinoma

A Bytyqi, G Karanikas, M Mayerhöfer, O Koperek, B Niederle, M Hartenbach

A4 Variations of clinical PET/MR operations: An international survey on the clinical utilization of PET/MRI

T Beyer, K Herrmann, J Czernin

A5 Standard Dixon-based attenuation correction in combined PET/MRI: Reproducibility and the possibility of Lean body mass estimation

I Rausch, P Rust, MD DiFranco, M Lassen, A Stadlbauer, ME Mayerhöfer, M Hartenbach, M Hacker, T Beyer

A6 High resolution digital FDG PET/MRI imaging for assessment of ACL graft viability

K Binzel, R Magnussen, W Wei, MU Knopp, DC Flanigan, C Kaeding, MV Knopp

A7 Using pre-existing hematotoxicity as predictor for severe side effects and number of treatment cycles of Xofigo therapy

A Leisser, M Nejabat, M Hartenbach, G Kramer, M Krainer, M Hacker, A Haug

A8 QDOSE – comprehensive software solution for internal dose assessment

Wencke Lehnert, Karl Schmidt, Sharok Kimiaei, Marcus Bronzel, Andreas Kluge

A9 Clinical impact of Time-of-Flight on next-generation digital PET imaging of Yttrium-90 radioactivity following liver radioembolization

CL Wright, K Binzel, J Zhang, Evan Wuthrick, Piotr Maniawski, MV Knopp

A10 Snakes in patients! Lessons learned from programming active contours for automated organ segmentation

M Blaickner, E Rados, A Huber, M Dulovits, H Kulkarni, S Wiessalla, C Schuchardt, RP Baum, B Knäusl, D Georg

A11 Influence of a genetic polymorphism on brain uptake of the dual ABCB1/ABCG2 substrate [11C]tariquidar

M Bauer, B Wulkersdorfer, W Wadsak, C Philippe, H Haslacher, M Zeitlinger, O Langer

A12 Outcome prediction of temporal lobe epilepsy surgery from P-glycoprotein activity. Pooled analysis of (R)-[11C]-verapamil PET data from two European centres

M Bauer, M Feldmann, R Karch, W Wadsak, M Zeitlinger, MJ Koepp, M-C Asselin, E Pataraia, O Langer

A13 In-vitro and in-vivo characterization of [18F]FE@SNAP and derivatives for the visualization of the melanin concentrating hormone receptor 1

M Zeilinger, C Philippe, M Dumanic, F Pichler, J Pilz, M Hacker, W Wadsak, M Mitterhauser

A14 Reducing time in quality control leads to higher specific radioactivity of short-lived radiotracers

L Nics, B Steiner, M Hacker, M Mitterhauser, W Wadsak

A15 In vitro 11C-erlotinib binding experiments in cancer cell lines with epidermal growth factor receptor mutations

A Traxl, Thomas Wanek, Kushtrim Kryeziu, Severin Mairinger, Johann Stanek, Walter Berger, Claudia Kuntner, Oliver Langer

A16 7-[11C]methyl-6-bromopurine, a PET tracer to measure brain Mrp1 function: radiosynthesis and first PET evaluation in mice

S Mairinger, T Wanek, A Traxl, M Krohn, J Stanek, T Filip, M Sauberer, C Kuntner, J Pahnke, O Langer

A17 18F labeled azidoglucose derivatives as “click” agents for pretargeted PET imaging

D Svatunek, C Denk, M Wilkovitsch, T Wanek, T Filip, C Kuntner-Hannes, J Fröhlich, H Mikula

A18 Bioorthogonal tools for PET imaging: development of radiolabeled 1,2,4,5-Tetrazines

C Denk, D Svatunek, T Wanek, S Mairinger, J Stanek, T Filip, J Fröhlich, H Mikula, C Kuntner-Hannes

A19 Preclinical evaluation of [18F]FE@SUPPY- a new PET-tracer for oncology

T Balber, J Singer, J Fazekas, C Rami-Mark, N Berroterán-Infante, E Jensen-Jarolim, W Wadsak, M Hacker, H Viernstein, M Mitterhauser

A20 Investigation of Small [18F]-Fluoroalkylazides for Rapid Radiolabeling and In Vivo Click Chemistry

C Denk, D Svatunek, B Sohr, H Mikula, J Fröhlich, T Wanek, C Kuntner-Hannes, T Filip

A21 Microfluidic 68Ga-radiolabeling of PSMA-HBED-CC using a flow-through reactor

S Pfaff, C Philippe, M Mitterhauser, M Hartenbach, M Hacker, W Wadsak

A22 Influence of 24-nor-ursodeoxycholic acid on hepatic disposition of [18F]ciprofloxacin measured with positron emission tomography

T Wanek, E Halilbasic, M Visentin, S Mairinger, B Stieger, C Kuntner, M Trauner, O Langer

A23 Automated 18F-flumazenil production using chemically resistant disposable cassettes

P Lam, M Aistleitner, R Eichinger, C Artner

A24 Similarities and differences in the synthesis and quality control of 177Lu-DOTA-TATE, 177Lu -HA-DOTA-TATE and 177Lu-DOTA-PSMA (PSMA-617)

H Eidherr, C Vraka, A Haug, M Mitterhauser, L Nics, M Hartenbach, M Hacker, W Wadsak

A25 68Ga- and 177Lu-labelling of PSMA-617

H Kvaternik, R Müller, D Hausberger, C Zink, RM Aigner

A26 Radiolabelling of liposomes with 67Ga and biodistribution studies after administration by an aerosol inhalation system

U Cossío, M Asensio, A Montes, S Akhtar, Y te Welscher, R van Nostrum, V Gómez-Vallejo, J Llop

A27 Fully automated quantification of DaTscan SPECT: Integration of age and gender differences

F VandeVyver, T Barclay, N Lippens, M Troch

A28 Lesion-to-background ratio in co-registered 18F-FET PET/MR imaging – is it a valuable tool to differentiate between low grade and high grade brain tumor?

L Hehenwarter, B Egger, J Holzmannhofer, M Rodrigues-Radischat, C Pirich

A29 [11C]-methionine PET in gliomas - a retrospective data analysis of 166 patients

N Pötsch, I Rausch, D Wilhelm, M Weber, J Furtner, G Karanikas, A Wöhrer, M Mitterhauser, M Hacker, T Traub-Weidinger

A30 18F-Fluorocholine versus 18F-Fluorodeoxyglucose for PET/CT imaging in patients with relapsed or progressive multiple myeloma: a pilot study

T Cassou-Mounat, S Balogova, V Nataf, M Calzada, V Huchet, K Kerrou, J-Y Devaux, M Mohty, L Garderet, J-N Talbot

A31 Prognostic benefit of additional SPECT/CT in sentinel lymph node mapping of breast cancer patients

S Stanzel, G Pregartner, T Schwarz, V Bjelic-Radisic, B Liegl-Atzwanger, R Aigner

A32 Evaluation of diagnostic value of TOF-18F-FDG PET/CT in patients with suspected pancreatic cancer

S Stanzel, F Quehenberger, RM Aigner

A33 New quantification method for diagnosis of primary hyperpatahyroidism lesions and differential diagnosis vs thyropid nodular disease in dynamic scintigraphy

A Koljević Marković, Milica Janković, V Miler Jerković, M Paskaš, G Pupić, R Džodić, D Popović

A34 A rare case of diffuse pancreatic involvement in patient with merkel cell carcinoma detected by 18F-FDG

MC Fornito, D Familiari

A35 TSH-stimulated 18F-FDG PET/CT in the diagnosis of recurrent/metastatic radioiodine-negative differentiated thyroid carcinomas in patients with various thyroglobuline levels

P Koranda, H Polzerová, I Metelková, L Henzlová, R Formánek, E Buriánková, M Kamínek

A36 Breast Dose from lactation following I131 treatment

WH Thomson, C Lewis

A37 A new concept for performing SeHCAT studies with the gamma camera

WH Thomson, J O’Brien, G James, A Notghi

A38 Whole body F-18-FDG-PET and tuberculosis: sensitivity compared to x-ray-CT

H Huber, I Stelzmüller, R Wunn, M Mandl, F Fellner, B Lamprecht, M Gabriel

A39 Emerging role 18F-FDG PET-CT in the diagnosis and follow-up of the infection in heartware ventricular assist system (HVAD)

MC Fornito, G Leonardi

A40 Validation of Poisson resampling software

WH Thomson, J O’Brien, G James

A41 Protection of PET nuclear medicine personnel: problems in satisfying dose limit requirements

J Hudzietzová, J Sabol, M Fülöp

Fusion of structural and functional cardiac magnetic resonance imaging data for studying ventricular fibrillation

Magnetic Resonance Imaging (MRI) techniques such as Current Density Imaging (CDI) and Diffusion Tensor Imaging (DTI) provide a complementing set of imaging data that can describe both the functional and structural states of biological tissues. This paper presents a Joint Independent Component Analysis (jICA) based fusion approach which can be utilized to fuse CDI and DTI data to quantify the differences between two cardiac states: Ventricular Fibrillation (VF) and Asystolic/Normal (AS/NM). Such an approach could lead to a better insight on the mechanism of VF. Fusing CDI and DTI data from 8 data sets from 6 beating porcine hearts, in effect, detects the differences between two cardiac states, qualitatively and quantitatively. This initial study demonstrates the applicability of MRI-based imaging techniques and jICA-based fusion approach in studying cardiac arrhythmias.

A novel approach to quantification of real and artifactual components of current density imaging for phantom and live heart

Spatial distribution of injected current in a subject could be calculated and visualized through current density imaging (CDI). Calculated CDI paths however have a limited degree of accuracy due to both avoidable methodological errors and inevitable limitations dictated by MR imaging constraints. The source and impact of these limitations are scrutinized in this paper. Quantification of such limitations is an essential step prior to passing any judgment about the results especially in biomedical applications. An innovative technique along with metrics for evaluation of range of errors using baseline and phase cycle MR images is proposed in this work. The presented approach is helpful in pinpointing the local artifacts (areas for which CDI results are suspect), evaluation of global noises and artifacts and assessment of the effect of approximation algorithms on real and artifactual components. We will demonstrate how this error/reliability evaluation is applicable to interpretation of CDI results and in this framework, report the CDI results for an artificial phantom and a live pig heart in Langendorff setup. It is contended here that using this method, the inevitable trade-off between details and approximations of CDI components could be monitored which provides a great opportunity for robust interpretation of results. The proposed approach could be extended, adapted and used for statistical analysis of similar methods which aim at mapping current and impedance based on magnetic flux images obtained through MRI.

99mTc tetrofosmin myocardial perfusion scintigraphy in CAD. Performance with early and standard delayed acquisition and fractional flow reserve

AIM

Early stress imaging (15 min after injection of the radiopharmaceutical) in 99mTc tetrofosmin myocardial perfusion scintigraphy (MPS) has been shown feasible in comparison to standard imaging after 45 minutes, but the effects on image quality and diagnostic accuracy ask for further evaluation.

PATIENTS, METHODS

97 patients (61 men, 36 women, age 69 ± 11 years) underwent both early (EA) and standard (SA) acquisition (after 14 ± 4 min and 43 ± 6 min, respectively) using 99mTc tetrofosmin gated SPECT with iterative reconstruction. Sub-diaphragmatic tracer activity and image quality was scored in a 4-point scale by blinded observers. Semiquantitative myocardial perfusion analysis was performed on a 17-segment model using standard cardiac quantification SPECT software (4 DM-SPECT). Stenoses of indeterminate haemodynamic significance were validated by measurement of fractional flow reserve (FFR).

RESULTS

Extra-cardiac tracer activity was more commonly found in EA (43%) than in SA (38%), but without any diagnostic impact in > 95% of the patients. The mean summed stress score was significantly higher for early than standard imaging (6.4 ± 6.3 vs. 5.6 ± 6.1, p = 0.009). The amount of ischaemic area was not significantly different (EA: 9.1 ± 6.7 % vs. SA: 7.8 ± 6.9 %). The mean stress ejection fraction was 52 ± 11% (EA) compared to 55 ± 11 % (SA) (p = ns). FFR was inversely related to SDS at early (r = -0.704, p < 0.05) and standard (r = -0.678, p < 0.05) acquisition. All patients with a FFR < 0.8 (considered as hemodynamically significant stenoses) revealed a positive scan.

CONCLUSION

Stress 99mTc tetrofosmin MPS with early acquisition is feasible and at least equally accurate when iterative reconstruction is applied.

Lack of renal protection of ultrafiltration during cardiac surgery: a randomized clinical trial

AIM

The objective of this study was to determine the intraoperative ultrafiltration effect on postoperative AKI.

METHODS

In this prospective randomized clinical trail, 159 patients scheduled for elective cardiac surgery, were randomly assigned to either hemofilter (N.=87) or control group (N.=72). The primary and secondary outcomes were AKI (defined as ≥50% increase in the serum creatinine level) and increased urinary neutrophil gelatinase-associated lipocalin (NGAL) in the postoperative period, respectively.

RESULTS

The two groups were similar with respect to comorbidities and also surgical procedure, except ultrafiltration. The incidence of AKI was equal in the both groups (11% vs. 5%, P=0.2, respectively). Creatinine increased after surgery (P=0.00) without significant differences between the both groups (P=0.2). Urinary NGAL also showed no significant difference between the groups. Age, euroscore, hyperlipidemia, pulmonary disease and urinary volume during operation correlated with the development of AKI. Postoperative blood loss was less in the hemofilter than control group (820±550 mL vs. 1100±630 mL, P=0.04). There was no difference in the length of intubation and stay in intensive care unit.

CONCLUSION

Routine use of ultrafiltration during cardiac surgery offers no advantages in renal protection and reduction of AKI incidence.

Analysis of reliability metrics and quality enhancement measures in current density imaging

Low frequency current density imaging (LFCDI) is a magnetic resonance imaging (MRI) technique which enables calculation of current pathways within the medium of study. The induced current produces a magnetic flux which presents itself in phase images obtained through MRI scanning. A class of LFCDI challenges arises from the subject rotation requirement, which calls for reliability analysis metrics and specific image registration techniques. In this study these challenges are formulated and in light of proposed discussions, the reliability analysis of calculation of current pathways in a designed phantom and a pig heart is presented. The current passed is measured with less than 5% error for phantom, using CDI method. It is shown that Gauss's law for magnetism can be treated as reliability metric in matching the images in two orientations. For the phantom and pig heart the usefulness of image registration for mitigation of rotation errors is demonstrated. The reliability metric provides a good representation of the degree of correspondence between images in two orientations for phantom and pig heart. In our CDI experiments this metric produced values of 95% and 26%, for phantom, and 88% and 75% for pig heart, for mismatch rotations of 0 and 20 degrees respectively.

Imaging of bone metastases in prostate cancer: an update

Assessing bone metastases is often beyond the scope of plain - film radiography, and nuclear imaging in particular with bone scintigraphy has proved the mainstay for detection of bony disease for over 40 years. Bone scanning with 99mTechnetium - labeled diphosphonates relies on the detection of pathological osteoblastic response elicited from malignant cells. This technique offers the advantage of whole body examination, low cost, availability and high sensitivity. However, it suffers from relative low specificity. The addition of single-photon emission computed tomography (SPECT) to bone scintigraphy has markedly improved the diagnostic benefit. Although the accuracy of SPECT is significantly higher than that of planar scintigraphy, there is still room for improvement of anatomic localization and morphological characterization, a limitation that has currently been mainly overcome with the upcoming of combined SPECT-CT (computed tomography). Positron emission tomography (PET), a modality with higher spatial resolution than that of SPECT can be particularly helpful in detecting small lesions. Moreover, PET imaging using various specific radiotracers has the advantage of detecting malignant disease in both bone and soft tissues. It is highly sensitive mainly in detecting early bone marrow as well as for diagnosing lytic bony metastases and can be also reliably used to monitor therapy response. In this review, we present the current role of SPECT and PET in the imaging of skeletal metastases from prostate cancer.

Fluorocholine (18F) and sodium fluoride (18F) PET/CT in the detection of prostate cancer: prospective comparison of diagnostic performance determined by masked reading

AIM

The aim of this paper was to compare the diagnostic performance of positron emission tomography/computed tomography (PET/CT) with fluorocholine (18F) (FCH) or fluoride(18F) (FNa) for the detection of bone metastasis in patients with prostate cancer complaining from osteoarticular pain, taking into account whether they were referred for initial staging or recurrence localization. The initial hypothesis was that FCH site-based specificity would be superior to that of F Na, with no loss in sensitivity.

METHODS

Forty-two patients were enrolled in this prospective study, underwent both PET/CTs and were then followed-up for at least 6 months. The standard of truth (SOT) about the presence/absence and location of bone metastasis could be determined in 40 patients, by 2 independent medical assessors, blinded to the results of both PET/CTs. The comparison was performed according to the guideline of the European Medicines Agency, i.e. based on the results of blind reading with SOT as reference.

RESULTS

Bone extension was present in 22 patients and absent in 18. Patient-based performance for FCH vs. FNa was 91% vs. 91% for sensitivity, 89% vs. 83% for specificity and 90% vs. 88% for accuracy (no significant difference). Of 360 skeletal sites, 68 were malignant and 292 non-invaded. There was no significant difference in site-based performance in the group of patients referred at initial staging, but in the group of patients referred for suspicion of recurrence, FCH was significantly more specific than FNa (96% vs. 91%, P=0.033 with Obuchowski's correction) while sensitivity was the same, 89%.

CONCLUSION

Both radiopharmaceuticals, based on a very different metabolic approach, showed good diagnostic performance. If FCH is available, it should be preferred in patients after initial treatment.

Radicular cyst associated with a primary first molar: A case report

Radicular cysts arising from deciduous teeth are rare. This report presents a case of radicular cyst associated with a primary molar following pulp therapy and discusses the relationship between pulp therapy and the rapid growth of the cyst. The treatment consisted of enucleation of the cyst sac and extraction of the involved primary teeth and 20 months follow up of the patient. Early diagnosis of the lesion would have lead to a less aggressive treatment plan.

Prevalence of dyspepsia and its correlation with demographic factors and lifestyle in shiraz, southern iran

BACKGROUND Dyspepsia is a common disorder that can present many clinical dilemmas in patient management. Although not life-threatening, the symptoms are long-lasting, interfere with daily activities and have a significant impact upon quality of life. The aim of this study was to determine prevalence of dyspepsia and its relationship with demographic and socioeconomic factors, and lifestyle in an apparently healthy population in Shiraz, southern Iran. METHODS In a population-based study, 1978 subjects aged 35 years or older were interviewed from April to September 2004. A questionnaire consisting of demographic factors, lifestyle data and gastrointestinal symptoms was completed for each participant. The validity and reliability of the questionnaire were determined. RESULTS The prevalence of dyspepsia was 29.9%. The dyspeptic patients were classified as having ulcer-like (27.9%), dysmotility-like (26.2%) or unspecified dyspepsia (45.9%). The prevalence was higher in females, water-pipe smokers, NSAIDs users, and in those with psychological distress, recurrent headache, anxiety, nightmares and past history of gastrointestinal disease. Dyspepsia had an inverse relationship with consumption of pickles, fruits and vegetables, and with duration of meal ingestion. Subjects with dyspepsia symptoms were more likely to restrict their diet, take herbal medicine, use over-the-counter drugs, consult with physicians and consume medication advised by their friends. CONCLUSION This study reveals that dyspepsia has a high prevalence in Shiraz, southern Iran and is associated with several demographic factors, lifestyle and health-seeking behavior.

Posttherapeutic (131)I SPECT-CT offers high diagnostic accuracy when the findings on conventional planar imaging are inconclusive and allows a tailored patient treatment regimen

PURPOSE

The purpose of this prospective study was to determine the diagnostic impact and influence on patient treatment of posttherapeutic (131)I SPECT-CT when the findings on planar posttherapeutic whole-body scintigraphy (ptWBS) were inconclusive.

MATERIALS AND METHODS

A total of 53 SPECT-CT scans were performed in 41 patients with thyroid cancer after high-dose (131)I therapy (2.944 to 7.526 GBq (131)I) because of diagnostic uncertainty on ptWBS. Physiological uptake in the salivary glands, gastric mucosa, gut, nasal mucosa, urinary tract and liver were considered to be normal. Any other foci of increased (131)I uptake, except iodine uptake clearly located in the thyroid bed, were considered to be abnormal. The data were evaluated on a lesion and a patient basis.

RESULTS

Regarding neck lesions, SPECT-CT provided a diagnostic impact in 26/90 lesions (28.9%) and confirmed the diagnosis in 64/90 lesions (71.1%). On a patient basis, SPECT-CT changed N status in 12/33 patients (36.4%), provided a diagnostic impact in 21/33 patients (63.6%) and led to a treatment change in 8/33 patients (24.2%). Regarding lesions distant from the neck, SPECT-CT confirmed the diagnosis in 62/71 lesions (87.3%) and had a diagnostic impact in 9/71 lesions (12.7%). On a patient basis, SPECT-CT changed M status in 4/19 patients (21.1%), had a diagnostic impact in 14/19 patients (73.7%) and led to a treatment change in 2/19 patients (10.5%). Considering all patients, SPECT-CT led to a treatment change in 10/41 patients (24.4%).

CONCLUSION

Integrated SPECT-CT is a useful tool, especially in cases of diagnostic uncertainty and helps to individualize patient management.

FDG gamma camera PET equipped with one inch crystal and XCT. Assessment of myocardial viability

Metabolic imaging with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) is actually considered as the best method to detect and quantitatively assess myocardial tissue viability. The aim of this study was to investigate the accuracy of FDG gamma camera positron emission tomography (GCPET) imaging equipped with one inch NaI crystals in comparison to FDG dedicated PET (dPET) imaging as a "gold standard" in phantom and clinical studies.

PATIENTS, METHODS

Nineteen patients with coronary artery disease (CAD) underwent both imaging modalities. Phantom and clinical GCPET imaging were performed with a dual-headed, coincidence based gamma camera equipped with 1 inch thick NaI crystals and an x-ray tube (XCT) for attenuation correction (AC), as well as with a dedicated PET scanner with AC. (99m)Tc tetrofosmin single-photon emission tomography (SPET) studies were performed for assessment of myocardial perfusion, with AC.

RESULTS

Phantom studies showed a significant relation in segmental activity between FDG imaging with AC using GCPET and dPET (r = 0.91, p < 0.001). In clinical studies with AC correlation coefficients of mean segmental FDG uptake and regional defect size were r = 0.87 (p < 0.0001) and r = 0.83 (p < 0.0001), respectively. In regional analysis close agreement was even found in the most attenuated regions of the heart if AC was used in GCPET imaging. The overall agreement for detection of viable myocardium was 81% between FDG-dPET (AC) and FDG-GCPET (AC) and 74% between FDG-dPET (AC) and FDG-GCPET (NC).

CONCLUSION

This study suggests that the assessment of myocardial metabolism by means of FDG is feasible with a coincidence based gamma camera equipped with 1 inch thick NaI crystals if AC is performed. The results reveal a close concordance and agreement between FDG-dPET (AC) and FDG-GCPET (AC) as compared to FDG-GCPET (NC).

FDG gamma camera PET equipped with one inch crystal and XCT

Metabolic imaging with 2-[fluorine-18]-fluoro- 2-deoxy-D-glucose (FDG) is actually considered as the best method to detect and quantitatively assess myocardial tissue viability. The aim of this study was to investigate the accuracy of FDG gamma camera positron emission tomography (GCPET) imaging equipped with one inch NaI crystals in comparison to FDG dedicated PET (dPET) imaging as a „gold standard“ in phantom and clinical studies. Patients, methods: Nineteen patients with coronary artery disease (CAD) underwent both imaging modalities. Phantom and clinical GCPET imaging were performed with a dual-headed, coincidence based gamma camera equipped with 1 inch thick NaI crystals and an x-ray tube (XCT) for attenuation correction (AC), as well as with a dedicated PET scanner with AC. 99mTc tetrofosmin single-photon emission tomography (SPET) studies were performed for assessment of myocardial perfusion, with AC. Results: Phantom studies showed a significant relation in segmental activity between FDG imaging with AC using GCPET and dPET (r = 0.91, p <0.001). In clinical studies with AC correlation coefficients of mean segmental FDG uptake and regional defect size were r = 0.87 (p <0.0001) and r = 0.83 (p <0.0001), respectively. In regional analysis close agreement was even found in the most attenuated regions of the heart if AC was used in GCPET imaging. The overall agreement for detection of viable myocardium was 81% between FDG-dPET (AC) and FDG-GCPET (AC) and 74% between FDG-dPET (AC) and FDG-GCPET (NC). Conclusion: This study suggests that the assessment of myocardial metabolism by means of FDG is feasible with a coincidence based gamma camera equipped with 1 inch thick NaI crystals if AC is performed. The results reveal a close concordance and agreement between FDG-dPET (AC) and FDG-GCPET (AC) as compared to FDG-GCPET (NC).

Value of combined XCT/SPECT technology for avoiding false positive planar (123)I-MIBG scintigraphy

AIM

The clinical value of combined XCT/SPECT technology in a single device in patients undergoing (123)I-MIBG scintigraphy was analyzed.

METHODS

31 patients (19 men, 12 women; mean age 55 years, range: 31-79 years) demonstrating focal accumulation in planar (123)I-MIBG scan were further investigated with a double headed gamma camera with an X-ray tomograph mounted on the same gantry (GE Medical Systems, Millennium VG with Hawkeye, Milwaukee, USA) for anatomical definition of the focal (123)I-MIBG uptake. The patients were referred to (123)I-MIBG scintigraphy because of biochemically (81%) and/or clinically (19%) suspected pheochromocytoma.

RESULTS

In 23 out of 31 patients (74%) the fused images demonstrated physiological accumulation (i. e. intestinal, renal) of (123)I-MIBG. In two patients (6%) suspected adrenal MIBG-accumulation was caused by inhomogeneous liver uptake. In two patients (6%) focal abdominal accumulation was correctly localised in the adrenal glands. Furthermore, the differentiation of bone metastasis from a local recurrence for phaeochromocytoma was accurately possible for two patients (6%). Adrenal lesions mimicking liver foci were correctly localised in the remaining two patients (6%).

CONCLUSION

Our study demonstrates the clinical value of XCT/SPECT in a single device in patients demonstrating focal (123)I-MIBG uptake in planar scintigraphy. The combined XCT/SPECT technology provides a higher diagnostic accuracy.

Iodine-123-vascular endothelial growth factor-165 (123I-VEGF165). Biodistribution, safety and radiation dosimetry in patients with pancreatic carcinoma

AIM

Imaging with radiolabelled vascular endothelial growth factor (VEGF) has been developed for the localisation and diagnosis of a variety of human solid tumors including gastrointestinal tumors.

METHODS

In this study we investigated the biodistribution, safety and absorbed dose of iodine-123 radiolabelled VEGF(165) ((123)I-VEGF(165)) in 9 patients with pancreatic carcinoma. Following intravenous administration of (123)I-VEGF(165) (189+/-17 MBq; <130 pmole (<5 microg) VEGF(165) per patient), sequential images were recorded during the initial 30 min PI. Serial whole-body images were acquired in anterior and posterior views at various time points. All patients underwent single-photon emission tomography (SPET) imaging. Dosimetry calculations were performed on the basis of gamma camera data. Estimates of radiation absorbed dose were calculated using the MIRDOSE 3 program.

RESULTS

The highest absorbed organ doses were found to be thyroid (0.058+/-0.004 mGy/MBq), spleen (0.046+/- 0.017 mGy/MBq), urinary bladder (0.04+/-0.02 mGy/MBq), lungs (0.034+/-0.009 mGy/MBq) and kidneys (0.033+/-0.005 mGy/MBq). The effective dose was estimated to be 0.017+/-0.002 mSv/MBq. A majority of primary pancreatic tumors and their metastases were visualized by (123)I-VEGF(165) scan.

CONCLUSION

In vitro binding results confirmed specific binding of (123)I-VEGF(165) to pancreatic tumor cells and tissues. (123)I-VEGF(165) shows favorable dosimetry and is a safe radiopharmaceutical that may be of potential value for the imaging of VEGF receptor status in vivo.

Oral fluoroquinolone therapy results in drug adsorption on ureteral stents and prevention of biofilm formation

The oral administration of ciprofloxacin (250mg bid) and ofloxacin (300mg bid) in 40 patients with ureteral stents, led to drug levels on all the device surfaces that were higher than the minimum inhibitory concentration (MIC) of Escherichia coli (0.004--0.015 mg/l), the most common uropathogen. The drug levels in the film were higher than the MIC of other common pathogens, namely Pseudomonas aeruginosa (0.25--1.0 mg/l), Enterococcus faecalis (0.25--2.0 mg/l) and Staphylococcus aureus (0.12--0.5 mg/l) in a few cases (six, three and 14 cases out of 40, respectively). For both antibiotics, the concentrations were greater than the MIC of many uropathogens on the film surrounding the devices (0.89 vs 0.31 mg/l respectively, P=0.05), and on the devices themselves (0.22 vs. 0.12 mg/l, P=0.207). Adsorption of the antibiotics was higher to the film than to the stent (P<0.0001). Ciprofloxacin concentration on the film surrounding the stents was significantly higher than that of ofloxacin (P=0.05), while there was no statistical concentration difference between the two antibiotics adsorbed onto the actual devices (P=0.207). No bacteria were found in patients' urine and no biofilms were detected. This is the first report of an oral antibiotic being adsorbed onto medical devices. It potentially provides a new approach of preventing infection, and avoids the need to pre-coat devices with agents whose use will be restricted once bacteria develop resistance to them. If biomaterial properties can be enhanced to increase further the adsorptive concentration of drug, the risk of infections and recalcitrant biofilm formation could be significantly reduced in a highly susceptible patient population.

N-(3-Acyloxy-2-benzylpropyl)-N'-(4-hydroxy-3-methoxybenzyl) thiourea derivatives as potent vanilloid receptor agonists and analgesics

A series of N-(3-acyloxy-2-benzylpropyl)-N'-(4-hydroxy-3-methoxybenzyl) thiourea derivatives were investigated as vanilloid receptor ligands in an effort to discover a novel class of analgesics. The proposed pharmacophore model of resiniferatoxin. which includes the C20 homovanillic moiety, the C3-carbonyl and the orthoester phenyl ring as key pharmacophoric groups, was utilized as a guide for drug design. The compounds were synthesized after several steps from diethylmalonate and evaluated in vitro in a receptor binding assay and in a capsaicin-activated channel assay. Additional evaluation of analgesic activity, anti-inflammatory activity and pungency was conducted in animal models by the writhing test, the ear edema assay, and the eye-wiping test, respectively. Among the new compounds, 23 and 28 were found to be the most potent receptor agonists of the series with Ki values of 19 nM and 11 nM, respectively. Their strong in vitro potencies were also reflected by an excellent analgesic profile in animal tests with ED50 values of 0.5 microg kg for 23 and 1.0 microg/kg for 28. Relative to capsaicin these compounds appear to be ca. 600 and 300 times more potent. Both 23 and 28 were found to be less pungent than capsaicin based on the eye-wiping test. However, the compounds did not show significant anti-inflammatory activity. A molecular modeling study comparing the energy-minimized structures of resiniferatoxin and 35 demonstrated a good correlation in the spatial disposition of the corresponding key pharmacophores. The thioureas described in this investigation, which were designed as simplified resiniferatoxin surrogates, represent a novel class of potent vanilloid receptor agonists endowed with potent analgesic activity and reduced pungency.

Effect of a tyrosine 155 to phenylalanine mutation of protein kinase cdelta on the proliferative and tumorigenic properties of NIH 3T3 fibroblasts

Tyrosine phosphorylation has emerged as an important mechanism in the regulation of enzyme function. In this paper, we describe a mutant of PKCdelta altered at a single tyrosine residue which has the opposite effect compared with wild-type PKCdelta on the growth characteristics of NIH 3T3 cells. Overexpression of wild-type PKCdelta results in a decreased growth rate and a lower cell density at confluency. On the other hand, overexpression of PKCdelta with a mutation from tyrosine to phenylalanine at position 155 results in a significantly higher rate of growth and a higher density at confluency compared with vector controls. Moreover, these cells are able to grow in soft agar and to form tumors in nude mice. In contrast to kinase negative PKC constructs, this mutant maintains in vitro kinase activity and shows a subcellular localization and a translocation pattern that are similar to those of the wild-type PKCdelta. Whether the altered biological effect is due to the missing phosphorylation on tyrosine or the mutation from tyrosine to phenylalanine per se remains under investigation.

The guanine nucleotide exchange factor RasGRP is a high -affinity target for diacylglycerol and phorbol esters

RasGRP is a recently described guanine nucleotide exchange factor (GEF) that possesses a single C1 domain homologous to that of protein kinase C (PKC). The phorbol ester [(3)H]phorbol 12, 13-dibutyrate ([(3)H]PDBu) bound to this C1 domain (C1-RasGRP) with a dissociation constant of 0.58 +/- 0.08 nM, similar to that observed previously for PKC. Likewise, the potent PKC activator bryostatin 1, a compound currently in clinical trials, showed high affinity binding for C1-RasGRP. Structure activity analysis using several phorbol ester analogs showed both similarities and differences in ligand selectivity compared with PKC; the differences were comparable in magnitude to those between different PKC isoforms. Similarly, the potency of the PKC inhibitor calphostin C to inhibit [(3)H]PDBu binding to C1-RasGRP was similar to that observed for PKC. In contrast to the relative similarities in ligand recognition, the lipid cofactor requirements differed between RasGRP and PKC. The C1 domain plus the EF-hand motif of RasGRP (C1EF-RasGRP) was markedly less dependent on acidic phospholipids than was PKCalpha. The differences in lipid requirements were reflected in differential ligand selectivity under conditions of limiting lipid. Despite the presence of twin EF-hand like motifs, calcium did not affect the binding of [(3)H]PDBu to C1EF-RasGRP. We conclude that RasGRP is a high affinity receptor for phorbol esters and diacylglycerol. RasGRP thus provides a direct link between diacylglycerol generation or phorbol ester/bryostatin treatment and Ras activation.

Differential roles of the tandem C1 domains of protein kinase C delta in the biphasic down-regulation induced by bryostatin 1

Bryostatin 1 (Bryo), currently in clinical trials, has been shown to induce a biphasic concentration-response curve for down-regulating protein kinase C (PKC) delta, with protection of the enzyme from down-regulation at high Bryo doses. In our ongoing studies to identify the basis for this unique behavior of PKCdelta, we examined the participation of the two ligand binding sites (C1a and C1b) in the regulatory domain of the enzyme. Three mutants of PKCdelta prepared by introducing a point mutation in either C1a or Clb or both C1a and Clb were overexpressed in NIH 3T3 cells. All of the constructs retained a biphasic response to down-regulation assessed after 24-h treatment with Bryo. However, the roles of the individual C1 domains were different for the two phases of the response. For down-regulation, both the C1a and the C1b mutants displayed equivalent 3-4-fold reductions in their affinities for the ligand. For protection from down-regulation, a reduced protection was observed for the C1a mutant, which showed a broader biphasic curve compared with those for wild-type PKCdelta and the Clb mutant. Like wild-type PKCdelta, all of the mutants showed the same subcellular partitioning of the protected enzyme to the particulate fraction of the cells, arguing against changes in sensitivity to Bryo due to differences in localization. Likewise, relatively similar patterns of localization were observed using green fluorescent protein-PKCdelta constructs. We conclude that the C1 domains of PKCdelta do not have equivalent roles in inducing protection against Bryo-induced down-regulation. The C1a domain plays a critical role in conferring the degree of protection at high concentrations of Bryo. Elucidation of the differential effect of Bryo on PKCdelta may suggest strategies for the design of novel ligands with Bryo-like activities.

3-Acyloxy-2-phenalkylpropyl amides and esters of homovanillic acid as novel vanilloid receptor agonists

A series of 3-acyloxy-2-phenalkylpropyl amides and esters of homovanillic acid were designed and synthesized as vanilloid receptor agonists containing the three principal pharmacophores of resiniferatoxin. Amide analogues 23, 5 and 11 were found to be potent agonists in vanilloid receptor assay both for ligand binding and for activation.

Conformationally constrained analogues of diacylglycerol (DAG). 15. The indispensable role of the sn-1 and sn-2 carbonyls in the binding of DAG-lactones to protein kinase C (PK-C)

The binding mode of DAG-lactones to PK-C was investigated using the C1b domain from the X-ray structure of the phorbol ester/C1b complex of PK-C delta as a template. Modeling experiments revealed two binding alternatives in which one of the carbonyls of the DAG lactones remained uninvolved with the protein. Experimentally, however, the removal of either sn-1 or sn-2 carbonyls caused a dramatic drop in binding affinity towards PK-C. Although it was not possible to discriminate between the two binding alternatives of the DAG-lactones, the study demonstrates an important role for the additional carbonyl group. The function of this group could be equivalent to that of the C-9(OH)/C-13 (C = O) motif in phorbol esters, which also appears free of interactions in the phorbol ester/C1b complex. This role presumably reflects interaction with the phosholipid head groups required for high affinity binding under the conditions of the biological assays.

Effect of antibiotic treatment on receptivity of uroepithelial cells to uropathogens

The management of female patients with recurrent urinary tract infections still remains a problem, and long-term prophylactic or short intermittent courses of antibiotics are the standard forms of therapy. In this report, 10 patients were examined for the effects of long- and short-term treatment with trimethoprim-sulfamethoxazole (TMP-SMX) antibiotics on the receptivity of uroepithelial cells to bacterial adherence. The urine of all patients was sterile while on antibiotic therapy. Few bacteria were found adherent to the cells from adult patients (group 1, mean age 36 years) on long-term antibiotics, but the cells were highly receptive to uropathogens in vitro, especially for Escherichia coli expressing mannose-resistant adhesins. Controls of age-matched adult females were included and in vitro adherence levels were found to be higher for those women with a history of urinary tract infection compared with those with no past record of infection. In the second group, elderly patients (mean age 87 years) presented with bacteriuria, and their uroepithelial cells were found to be colonized by uropathogens to a significantly greater extent than their controls. The adherent population was reduced during 7-day TMP-SMX antibiotic treatment, but increased posttherapy, particularly in two patients who subsequently became reinfected. The in vitro results showed that uroepithelial cells retain their receptivity to uropathogenic adherence, both during and after treatment. Although antibiotics eradicate uropathogens from the urinary tract, patients remain susceptible to recolonization by uropathogens and are at risk of reinfection after completion of therapy.

Neoplastic potential in patients with disorders of sexual differentiation

The occurrence of tumors was determined in 157 patients with disorders of sexual differentiation at a major pediatric hospital from 1960 to 1980. Gonadoblastoma developed in 2 of the 4 patients with mixed gonadal dysgenesis (MGD) who had not had bilateral gonadectomy; this indicates the need for early gonadectomy in such cases. Gonadal embryonal carcinoma developed in 1 child with Turner's syndrome (1 of 71). Four cases of nephroblastoma occurred, 1 in a child with MGD (1 of 18) and 3 in male pseudohermaphrodites (3 of 35). The nature of the defect linking male pseudohermaphroditism with Wilms tumor remains to be established.

External genital abnormalities associated with Wilms tumor

The records of 170 patients with unilateral and 18 patients with bilateral Wilms tumor and 6 patients with congenital mesoblastic nephroma were reviewed for abnormalities of the external genitalia. There were 4 patients with cryptorchism, 1 with hypospadias, 1 with mixed gonadal dysgenesis, and 3 with male pseudohermaphroditism. Of the group, these 9 patients had earlier symptoms; 6 of them were under two years old. Five patients (27.7%) with bilateral Wilms tumors had external genital anomalies in contrast to only 4 (2.3%) of those with unilateral tumors. One of the 9 children with genital anomalies had unilateral congenital mesoblastic nephroma; the others had Wilms tumor. In all cases the histologic subtypes were unusual. These observations substantiate the previously reported association between external genital abnormalities and Wilms tumor and also represent a somewhat higher than expected incidence. The children with this association are remarkable for the high frequency of a particular histologic type of tumor and for the high incidence of bilaterality. The high incidence of Wilms tumors in the male pseudohermaphrodite population presented suggests that such patients should be monitored for development of renal tumors.

Familial persistent müllerian duct syndrome

We found persistent müllerian duct structures in 2 phenotypically normal brothers who had undergone an operation for inguinal hernia. The older boy had transverse testicular ectopia and his younger brother had unilateral cryptorchidism. Bilateral orchiopexy was done with excision of the fallopian tubes, uterus and upper vagina. Histological examination showed normal testes in both patients. Since there is a risk of testicular malignancy in such patients, long-term followup is mandatory.

Gender assignment in male pseudohermaphrodite children

Experience with male pseudohermaphrodites at The Hospital for Sick Children, Toronto, from 1976 to 1981 was reviewed to identify factors that had influenced gender assignment. Seventeen children with microphallus, ambiguous genitalia, and 46 XY karoytype were studied. Five had been raised as females and 12 as males. Of those raised as females, 3 were from families with prior experience of androgen insensitivity. The other 2 had gross perineal abnormalities in addition to genital ambiguity. Of those raised as males 6 were not considered for gender reassignment, 4 because they were too old at presentation, and the other 2 because of parental refusal. In this series the parents were not prepared to accept gender reassignment on the basis of a small phallus alone. Androgen stimulation so far has been a reliable indicator of phallic growth potential, but long-term follow-up is necessary to determine its true value.

Learning experiences of medical students by different instructional methods

We made a prospective study to determine students' response and perception of the various instructional methods during their pediatric rotation. We found that even those students who were used to passive learning adapted to the more self active learning and became more interested in this method.

Profound spontaneous hypoglycaemia in congestive heart failure

Eleven cases of spontaneous hypoglycaemia in congestive heart failure in adults are reported. There were 5 males and 6 females, aged from 15 to 65 years (mean, 44 years). Blood sugar ranged from 2 to 42 mg/100 ml (mean 21 mg/100 ml). Six patients were in coma on admittance, 1 was confused, and 4 were conscious. The underlying condition was rheumatic valvular heart disease (3), chronic obstructive lung disease (4), cornonary heart disease (3) and cardiomyopathy (1). Five of the 11 patients died. The mechanism of hypoglycaemia is discussed and thought to be a combination of factors such as liver dysfunction, low calorie intake, malabsorption, and increased glusose utilization by ischaemic tissues, including the heart. It is recommended that in patients with congestive heart failure presenting with coma or confusion, blood sugar should be checked for possible hypoglycaemia.

Post-operative convulsions due to penicillin applied to the spinal theca

Two cases are described and discussed in which penicillin powder applied to the theca at the end of laminectomy caused delayed convulsions.