bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of 18F-FDG and 67Ga-citrate in sarcoidosis imaging
Authors: Wehrschuetz M. , Bisail B. , Woltsche M. , Schwarz T. , Lanz H. , Sorantin E. , Aigner R. M. , Prager E. 
Published: November 2007

SummaryAim: 67Ga citrate has been used long and successfully to diagnose and stage sarcoidosis. 18F-fluorodeoxyglucose (18F-FDG) has been suggested as a positron emission tomography (PET) tracer for sarcoidosis imaging. This study aimed to analyze possible advantages of 18F-FDG-PET over 67Ga citrate scintigraphy during the primary assessment of patients with sarcoidosis. Patients and methods: Twentyfour patients (11 men, 13 women, aged 52 years ±12.4) with histologically proven sarcoidosis were investigated with 18F-FDG and 67Ga citrate. Equipment included a fullring PET scanner (ECAT EXACT HR+, Siemens/CTI, Knoxville TN, USA) and a double-headed gamma camera (ECAM, Siemens, Illinois, USA) for scintigraphy. The mean time difference between the two studies was 6.5 days (range: 5–8 days). Results: There was a significant difference in the detection of pulmonary and nonpulmonary sarcoidosis lesions between planar 67Ga citrate scans and 18F-FDG-PET images (<0.0021). A total of 64 lesions were detected with 67Ga citrate scans in the thorax and elsewhere with a mean of 2.6 lesions (4%) per patient, while 85 lesions were found with 18F-FDG-PET, with a mean of 3.5 lesions (4.1%) per patient. There was complete agreement between 18F-FDG and 67Ga citrate in thoracic manifestations in four (16.6%) patients, and in non-thoracic manifestations in five (20.8%) patients. The interobserver variability showed a kappa value of 0.79. Conclusion: 67Ga citrate and 18F-FDG are useful tracers for diagnostic evaluation of thoracic sarcoidosis. 18F-FDG seems to be more suitable for imaging the mediastinum, the bi-hilar lymph nodes, the posterior regions of the lungs and non-thoracic lesions. Further prospective studies are needed to clarify the role of both tracers in early diagnosis and staging of sarcoidosis, and to resolve questions concerning medical treatment and follow-up.
Graves' disease and radioiodine therapy
Authors: Eschner W. , Sudbrock F. , Weber I. , Marx K. , Dietlein M. , Schicha H. , Kobe C. 
Published: November 2007

SummaryAim: This study was performed to determine the results of ablative radioiodine therapy (RIT) when the achieved dose in the thyroid was above 200 Gy and to characterize predictive factors for treatment outcome. Patients, methods: A total of 571 consecutive patients were observed for 12 months between July 2001 and June 2004. Inclusion criteria were a confirmed diagnosis Graves' disease, compensation of hyperthyroidism and withdrawal of antithyroid drugs two days before preliminary radioiodine-testing and RIT. The intended dose was 250 Gy and the therapeutically achieved dose was calculated from serial uptake measurements. The end-point measure was thyroid function 12 months after RIT; success was defined as elimination of hyperthyroidism. The relation between success rate and the achieved dose, thyroid volume, age and sex of patients, TSH- and TRAb-values and presence of ophthalmopathy was analysed. Results: Relief from hyperthyroidism was achieved in 96% of patients who received more than 200 Gy, even for thyroid volumes >40 ml. The success of ablative RIT was not influenced by age or sex of patients, or by TSH- or TRAb values or concomitant ophthalmopathy. The mean achieved dose in the thyroid was 298 Gy with a standard deviation of 74.6 Gy. Conclusion: To achieve a dose of over 200 Gy with the above standard deviation, we recommend calculating an intended dose of 250 Gy and using a dosimetric approach with early and late uptake values in the radioiodine test, to allow early therapeutic intervention should the posttherapeutic thyroid dose fall unexpectedly below 200 Gy.
Myocardial sympathetic innervation in diabetic patients with symptomatic coronary artery disease
Authors: Eckert S. , Fricke H. , Körfer J. , Weise R. , Lindner O. , Tschöpe D. , Horstkotte D. , Burchert W. , Fricke E. 
Published: November 2007

SummaryAim: In non-diabetic patients, sympathetic innervation can be preserved even if there is major impairment of myocardial blood supply. Matters may be more complex in diabetic patients because denervation can be caused by cardiac autonomic neuropathy (CAN) or by ischemic injury. Our aim was to determine whether restrictions in myocardial blood supply have a pronounced influence on sympathetic innervation in diabetics and if this effect can be differentiated from CAN. Patients, methods: We analyzed 20 diabetics with advanced coronary artery disease (CAD) and without known CAN. We determined quantitative myocardial blood flow using 13N-ammonia-PET, myocardial viability with 18F-FDG, and cardiac innervation with 11C-HED. We investigated the relationship between regional HED retention, blood flow, and coronary flow reserve (CFR). Attenuated heart rate response to adenosine was taken as indicator for CAN (HR ratio). Results: There was minor correlation of segmental stress flow and HED retention (r2 = 0.063, p <0.0001). Correlation improved when stress flow as well as HED retention were normalized to the individual maximum (r2 = 0.162, p <0.0001). In nine patients, a HR ratio < 1.2 implicated subclinical CAN. Duration of diabetic disease or glycaemic control (HbA1c) did not correlate with mean HED retention in the viable segments, but with its variation coefficient. Conclusions: As in non-diabetic patients, a slight correlation exists between CFR and sympathetic innervation. The sensitivity of sympathetic nerves to reductions in CFR does not seem to be increased as compared to the results reported for non-diabetics. Besides impaired blood supply, long duration of diabetic disease and bad glycaemic control also seem to impair sympathetic innervation provoking higher heterogeneity.
Whole-body imaging of oncologic patients using 16-channel PET-CT
Authors: Oei M. L. , Weckesser M. , Franzius C. , Wormanns D. , Schober O. , Heindel W. , Juergens K. U. 
Published: November 2007

SummaryAim: This study evaluated a MDCT protocol for contrast-enhanced 16-channel PET-CT with regard to scan range and duration of a whole-body 18F-FDG PET-CT examination, the occurrence of contrast-material induced artefacts and quantitative assessment of CT attenuation. Patients, methods: 205 patients (51.9 ± 12.4 years) with different malignant tumours underwent whole-body PET-CT; the study protocol had been approved by the institutional review board. Contrast-enhanced MDCT (16 ˟ 1.5 mm; 120 ml Iomeprol 3 ml/s, 50 ml saline chaser bolus, scan delay 70 s; oral contrast) was also used for attenuation correction. From MDCT data mean scan range and duration, occurrence of contrast media-induced artefacts, and mean CT densities of jugular (jv) and subclavian (scv), superior (vcs) and inferior (vci) caval, portal (pv), and bilateral external iliac veins, pulmonary (ap) and iliac arteries, descending thoracic and abdominal aorta, all cardiac chambers, as well as both liver lobes, spleen, adrenal glands and kidneys were determined. Results: Attenuation corrected PET images were free of contrast media-related image artefacts. Homogeneous contrast enhancement was found in the mediastinal veins (right/left jv 171 ± 34/171 ± 35, scv 127 ± 50/127 ± 40, vcs 153 ± 36 HU) and arteries (e.g. ap 145 ± 26/151 ± 26). Cardiac chambers, abdominal vessels (e.g. vci 138 ± 24, pv 159 ± 25 HU), and parenchymal organs revealed sufficient and homogenous contrast-enhancement in all cases. No beam-hardening artefacts occurred in the neighbourhood of the subclavian veins. Conclusion: The chosen whole-body 18F-FDG 16-slice PET-CT protocol allowed for craniocaudal CT scanning with high vessel and parenchymal contrast revealing no IV contrast-media induced artefacts in attenuation-corrected PET data sets.
Aspects of 6-[18F]fluoro-L-DOPA preparation
Authors: Füchtner F. , Zessin J. , Wüst F. , Mäding P. 
Published: November 2007

SummaryAim: Replacement of the ecologically harmful solvent Freon 11 (CFCl3) by chloroform for the module-assisted preparation of 6-[18F]fluoro-L-DOPA based on the electrophilic radiofluorodestannylation of the precursor N-formyl- 3,4-di-tert-butoxycarbonyloxy-6-(trimethylstannyl)- L-phenylalanine ethyl ester. Materials, methods: The TRACERlab Fx FDOPA module (GE Medical Systems) was used for the preparation of 6-[18F]fluoro-L-DOPA. Cyclotron- produced [18F]F2 gas (5 GBq) was passed through a cooled solution (5°C) of the stannyl precursor (45 mg) in CDCl3 (10 ml). After the [18F]fluorination step, HCl (2 ml, 6 mol/l) was added to the solution. Then the reaction mixture was heated at 80°C for 5 min under vacuum to evaporate the chloroform. The hydrolysis to remove the protecting groups was completed by heating the closed reactor at 130°C for 8 min. After cooling to 20°C the reaction mixture was purified by HPLC with two polymer-based RP columns (PRP-1, 7 μm, 10 X 250 mm, Hamilton) using a solution of AcOH/AcONa (pH 4.7) as eluent. The 6-[18F]fluoro- L-DOPA fraction was collected and sterile filtrated. Results: Three types of stabilised chloroform were tested for the radiofluorination of the precursor. Only by use of deuterochloroform stabilised with silver no significant losses of radioactivity were observed. Thus, 6-[18F]fluoro-L-DOPA purified by HPLC was obtained in decay-corrected radiochemical yields of 25±3%, ready for human use. Conclusion: CDCl3 has proved to be a convenient solvent for the module-assisted preparation of 6-[18F]fluoro-L-DOPA. In this way the use of the polluting Freon 11 can be avoided.
Restaging of patients with lymphoma
Authors: Pfluger T. , Schneider V. , Hacker M. , Bröckel N. , Morhard D. , Hundt W. , Bartenstein P. , Becker C. , Tiling R. , la Fougère C. 
Published: November 2007

SummaryAim: Assessment of the clinical benefit of i.v. contrast enhanced diagnostic CT (CE-CT) compared to low dose CT with 20 mAs (LD-CT) without contrast medium in combined [18F]-FDG PET/CT examinations in restaging of patients with lymphoma. Patients, methods: 45 patients with non-Hodgkin lymphoma (n = 35) and Hodgkin's disease (n = 10) were included into this study. PET, LD-CT and CECT were analyzed separately as well as side-by-side. Lymphoma involvement was evaluated separately for seven regions. Indeterminate diagnoses were accepted whenever there was a discrepancy between PET and CT findings. Results for combined reading were calculated by rating indeterminate diagnoses according the suggestions of either CT or PET. Each patient had a clinical follow-up evaluation for >6 months. Results: Region-based evaluation suggested a sensitivity/specificity of 66/93% for LD-CT, 87%/91% for CE-CT, 95%/96% for PET, 94%/99% for PET/LD-CT and 96%/99% for PET/CE-CT. The data for PET/CT were obtained by rating indeterminate results according to the suggestions of PET, which turned out to be superior to CT. Lymphoma staging was changed in two patients using PET/ CE-CT as compared to PET/LD-CT. Conclusion: Overall, there was no significant difference between PET/LD-CT and PET/CE-CT. However, PET/CE-CT yielded a more precise lesion delineation than PET/LD-CT. This was due to the improved image quality of CE-CT and might lead to a more accurate investigation of lymphoma.
Proposals for Sample Size Calculation Programs
Authors: Heinzl H. , Benner A. , Ittrich C. , Mittlböck M. 
Published: November 2007

Summary

Objectives
: Numerous sample size calculation programs are available nowadays. They include both commercial products as well as public domain and open source applications. We propose modifications for these programs in order to even better support statistical consultation during the planning stage of a two-armed clinical trial.

Methods
: Directional two-sided tests are commonly used for two-armed clinical trials. This may lead to a non-negligible Type III error risk in a severely underpowered study. In the case of a reasonably sized study the question for the so-called auxiliary alternative may evolve.

Results
: We propose that sample size calculation programs should be able to compute i) Type III errors and the so-called (q-values, ii) minimum sample sizes required to keep the (q-values below pre-specified levels, and iii) detectable effect sizes of the so-called auxiliary alternatives.

Conclusions
: Proposals iand ii are intended to help prevent irresponsibly underpowered clinical trials, whereas the proposal iii is meant as additional assistance for the planning of reasonably sized clinical trials.
Requirements Analysis of Information Services for Patients on a General Practitioner's Website
Authors: Abu-Hanna A. , Prins A. H. 
Published: November 2007

Summary

Objective
: To elicit and analyze information needs of patients and primary care physicians (GPs) regarding the information services (static and functional) that a GP's practice website should provide.

Methods
: To find candidate information services, we conducted a literature search and examined primary care physicians' websites, especially Dutch websites. Semi-structured depth interviews with the stakeholders, Dutch patients and GPs, were done to arrive at a final checklist. We then conducted a survey to elicit the level of importance associated with each service on the checklist. The data underwent statistical analysis and relevant requirements were formulated. The requirements were then validated by interviews. General website quality and usability aspects were elicited from the literature.

Results
: The research resulted in a checklist of 38 selected information services including their priority ratings for patients and GPs; a discrepancy list between GP and patient priorities; and a requirements document containing information services (14 static and 6 functional), and general quality and usability aspects (8 and 5).

Conclusion
: The following items occurred in the top 10 of both user groups: general practice information, information of local public health institutions, self-help information, repeat prescription, links to health websites. At the bottom on both priority lists were: links to journals, tests and forums. Dutch GPs are much more selective in terms of which information services to provide on-line. Discrepancy between the two groups concerns on-line services that seem to require a change to the GP's workflow, or those services that are not recognized for reimbursing the GP. Although the Dutch patients' requirements seem to generalize to other patients, the conflict list might depend on the primary care system.
Supporting Medical Planning by Mitigating Cognitive Load
Authors: Oettinger A. , Smith-Spark J. H. , Castillo F. D. , Monaghan V. E. L. , Fox J. , Glasspool D. W. 
Published: November 2007

Summary

Objectives
: Developing a care plan for a patient is a complex task, requiring an understanding of interactions and dependencies between procedures and of their possible outcomes for an individual patient. Decision support for planning has broader requirements than are typically considered in medical informatics applications. We consider the appropriate design of software to assist medical planning.

Methods
: The likely cognitive loads imposed by planning tasks were assessed with a view to directly supporting these via software.

Results
: Five types of cognitive load are likely to be important. A planning support system, REACT, was designed to ameliorate these cognitive loads by providing targeted dynamic feedback during planning. An initial evaluation study in genetic counselling indicates that the approach is successful in that role.

Conclusions
: The approach provides the basis of a general aid for visualizing, customizing and evaluating care plans.
User Acceptance of a Picture Archiving and Communication System
Authors: Pynoo B. , Devolder P. , Voet T. , Adang L. , Vercruysse J. , Duyck P. 
Published: November 2007

Summary

Objective:
The aim of this study is to gain insight into the individual user acceptance of PACS by the radiology department staff of the Ghent University Hospital. Hereto a basic – direct effects only – form of UTAUT was assessed.

Methods:
Ninety-four questionnaires were distributed and 56 usable questionnaires were returned (19 radiologists – 37 technologists). The questionnaire consisted of scales of Venkatesh et al. [13] for performance expectancy (PE), effort expectancy (EE), facilitating conditions (FC), social influence (SI), self-efficacy (SE), attitude (ATT), anxiety (ANX) and behavioral intention (BI), and a scale of Moore et al. [22] to assess the perceived voluntariness of PACS-use.

Results:
The reliability of all scales, except FC and voluntariness, was acceptable to good. The voluntariness scale was divided into a mandatoriness (MAN) and a voluntariness (VOL) measure. Both radiologists and technologists seem to welcome PACS, with radiologists having higher ratings on PE, EE, ATT, VOL and BI. Only PE and FC were salient for predicting BI, while EE and SI were not salient. Variance explained in behavioral intention to use PACS was 48%.

Conclusion:
Both radiologists and technologists were positive towards PACS and had strong intentions to use PACS. As other healthcare professionals, they appear to make their technology acceptance decision independent from their superiors, hereby focusing on usefulness rather than on ease of use. It is also important that support is supplied. Basic UTAUT is an adequate model to assess technology acceptance in a radiological setting.
Causes of death and case fatality rates among infants with down syndrome in metropolitan Atlanta
Authors: Shin Mikyong , Kucik James E. , Correa Adolfo 
Published: November 2007

AbstractBACKGROUND:There is limited population‐based information on the extent of underreporting of congenital heart defects (CHD) as a cause of death among infants with Down syndrome (DS) and on the variation in case fatality by presence of CHD and age at death.METHODS:Using data from the Metropolitan Atlanta Congenital Defects Program (MACDP), we identified infants with DS born 1979–2003. We used data from Georgia death certificates and the National Death Index to determine vital status and identify causes of death. Using MACDP records as a reference, we calculated the sensitivity and positive predictive value of reports of CHD as any cause of death or contributing condition in death certificates. We calculated race‐specific case fatality rate by infant's age at death and presence of CHD.RESULTS:CHD was the most frequently reported cause of death from death certificates; however, a review of causes of death and birth defects data indicated a potentially greater impact of CHD among DS infant deaths than could be determined from the reported cause of death. The case fatality rate among infants with DS was significantly higher among blacks than whites, with the greatest racial disparity observed among infants without CHD who died in the post‐neonatal period.CONCLUSIONS:Efforts are needed to improve reporting of causes of death related to CHD among infants with DS that would allow for a clearer assessment of determinants of case fatality among DS infants and identification of possible ways to reduce the racial disparities. Birth Defects Research (Part A) 79:775–780, 2007. © 2007 Wiley‐Liss, Inc.
Synchrotron X‐Ray Charge‐Density Study of Coordination Polymer [Mn(HCOO)2(H2O)2]∞
Authors: Poulsen Rasmus D. , Jørgensen Mads R. V. , Overgaard Jacob , Larsen Finn K. , Morgenroth Wolfgang , Graber Timothy , Chen Yu‐Sheng , Iversen Bo B. 
Published: November 2007

AbstractThree high‐quality single‐crystal X‐ray diffraction data sets have been measured under very different conditions on a structurally simple, but magnetically complex, coordination polymer, [Mn(HCOO)2(H2O)2]∞(1). The first data set is a conventional 100(2) K MoKαdata set, the second is a very high resolution 100(2) K data set measured on a second‐generation synchrotron source, while the third data set was measured with a tiny crystal on a high brilliance third‐generation synchrotron source at 16(2) K. Furthermore, the magnetic susceptibility (χ) and the heat capacity (Cp) have been measured from 2 to 300 K on pressed powder. The charge density of1was determined from multipole modeling of the experimental structure factors, and overall there is good agreement between the densities obtained separately from the three data sets. When considering the fine density features, the two 100 K data sets agree well with each other, but show small differences to the 16 K data set. Comparison with ab initio theory suggests that the 16 K APS data set provides the most accurate density. Topological analysis of the metal–ligand bonding, experimental 3d orbital populations on the Mn atoms, and Bader atomic charges indicate quite ionic, high‐spin metal atoms. This picture is supported by the effective moment estimated from the magnetization measurements (5.840(2) μB), but it is at variance with earlier spin density measurements from polarized neutron diffraction. The magnetic ordering originates from superexchange involving covalent interactions with the ligands, and non‐ionic effects are observed in the static deformation density maps as well as in plots of the valence shell charge concentrations. Overall, the present study provides a benchmark charge density that can be used in comparison with future metal formate dihydrate charge densities.
Intramolecular Alkyl Phosphine Dehydrogenation in Cationic Rhodium Complexes of Tris(cyclopentylphosphine)
Authors: Douglas Thomas M. , Brayshaw Simon K. , Dallanegra Romaeo , Kociok‐Köhn Gabriele , Macgregor Stuart A. , Moxham Gemma L. , Weller Andrew S. , Wondimagegn Tebikie , Vadivelu Prabha 
Published: November 2007

Abstract[Rh(nbd)(PCyp3)2][BArF4] (1) [nbd = norbornadiene, ArF = C6H3(CF3)2, PCyp3 = tris(cyclopentylphosphine)] spontaneously undergoes dehydrogenation of each PCyp3 ligand in CH2Cl2 solution to form an equilibrium mixture of cis‐[Rh{PCyp2(η2‐C5H7)}2][BArF4] (2 a) and trans‐[Rh{PCyp2(η2‐C5H7)}2][BArF4] (2 b), which have hybrid phosphine–alkene ligands. In this reaction nbd acts as a sequential acceptor of hydrogen to eventually give norbornane. Complex 2 b is distorted in the solid‐state away from square planar. DFT calculations have been used to rationalise this distortion. Addition of H2 to 2 a/b hydrogenates the phosphine–alkene ligand and forms the bisdihydrogen/dihydride complex [Rh(PCyp3)2(H)2(η2‐H2)2][BArF4] (5) which has been identified spectroscopically. Addition of the hydrogen acceptor tert‐butylethene (tbe) to 5 eventually regenerates 2 a/b, passing through an intermediate which has undergone dehydrogenation of only one PCyp3 ligand, which can be trapped by addition of MeCN to form trans‐[Rh{PCyp2(η2‐C5H7)}(PCyp3)(NCMe)][BArF4] (6). Dehydrogenation of a PCyp3 ligand also occurs on addition of Na[BArF4] to [RhCl(nbd)(PCyp3)] in presence of arene (benzene, fluorobenzene) to give [Rh(η6‐C6H5X){PCyp2(η2‐C5H7)}][BArF4] (7: X = F, 8: X = H). The related complex [Rh(nbd){PCyp2(η2‐C5H7)}][BArF4] 9 is also reported. Rapid (≈5 minutes) acceptorless dehydrogenation occurs on treatment of [RhCl(dppe)(PCyp3)] with Na[BArF4] to give [Rh(dppe){PCyp2(η2‐C5H7)}][BArF4] (10), which reacts with H2 to afford the dihydride/dihydrogen complex [Rh(dppe)(PCyp3)(H)2(η2‐H2)][BArF4] (11). Competition experiments using the new mixed alkyl phosphine ligand PCy2(Cyp) show that [RhCl(nbd){PCy2(Cyp)}] undergoes dehydrogenation exclusively at the cyclopentyl group to give [Rh(η6‐C6H5X){PCy2(η2‐C5H7)}][BArF4] (17: X = F, 18: X = H). The underlying reasons behind this preference have been probed using DFT calculations. All the complexes have been characterised by multinuclear NMR spectroscopy, and for 2 a/b, 4, 6, 7, 8, 9 and 17 also by single crystal X‐ray diffraction.
Fractionation, Characterization and Speciation of Heavy Metals in Composts and Compost‐Amended Soils
Authors: Iwegbue C. M. A. , Emuh F. N. , Isirimah N. O. , Egun A. C. 
Published: November 2007

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