Vascularity of tumors in children: evaluation with color Doppler imaging

Twenty-one tumors in 20 children were evaluated with duplex and color Doppler imaging to determine the value of the technique in assessing the origin and pattern of vascular supply and the degree of neovascularity. The origin of the vascular supply was detected correctly in 12 of 13 tumors that were subsequently resected. In five children, this aided in determining the organ from which the tumor originated, and in one child, it established the presence of a tumor by showing blood flow in the center of a suspected abscess. In 18 tumors, color Doppler imaging showed the pattern of the vascular supply. Eleven had a peripheral pattern, and seven had a central, branching pattern. Although individual tumor types appeared to have characteristic patterns of vascular supply, these were not specific enough to aid in making a specific diagnosis. When the degree of intratumor neovascularity was graded on the basis of the findings on color Doppler imaging, it agreed with the results of histologic evaluation in 16 of 19 tumors. In one tumor, neovascularity was overestimated, and in two, it was markedly underestimated. Our experience suggests that color Doppler imaging is useful in detecting the origin and pattern of vascular supply and the degree of intratumoral blood flow in a variety of solid tumors in children.     

Confidence intervals for weighted sums of Poisson parameters

Directly standardized mortality rates are examples of weighted sums of Poisson rate parameters. If the numbers of events are large then normal approximations can be used to calculate confidence intervals, but these are inadequate if the numbers are small. We present a method for obtaining approximate confidence limits for the weighted sum of Poisson parameters as linear functions of the confidence limits for a single Poisson parameter, the unweighted sum. The location and length of the proposed interval depend on the method used to obtain confidence limits for the single parameter. Therefore several methods for obtaining confidence intervals for a single Poisson parameter are compared. For single parameters and for weighted sums of parameters, simulation suggests that the coverage of the proposed intervals is close to the nominal confidence levels. The method is illustrated using data on rates of myocardial infarction obtained as part of the WHO MONICA Project in Augsburg, Federal Republic of Germany.     

Clinical features and management of amebic liver abscess. Experience from 29 patients

Summary 29 patients with amebic liver abscess were evaluated in a study to examine clinical picture, laboratory data, epidemiology, radiologic methods, and therapy. Since the clinical picture was unspecific a considerable amount of misdiagnoses occurred, and often originated from pulmonary symptoms. To establish diagnosis one should rely on the triad with positive amebic serology, intrahepatic scanning defects, and clinical picture with fever, right upper quadrant pain, and hepatomegaly. Nearly all patients had an exposure history of travel or immigration from endemic areas in the tropics. Medical therapy with metronidazole alone is highly effective and leads to defervescence and clinical improvement usually within 3–5 days. Invasive procedures, such as needle aspiration or surgical drainage of the abscess are rarely needed; these invasive methods neither shorten the course of the disease nor improve prognosis.Abbreviations E. histolytica Entamoeba histolytica - ALA Amebic liver abscess - ESR Erythrocyte sedimentation rate     

DNA typing: an important step forward?

In a collaborative project which was supported by 96 transplant centers, DNA typing of HLA-DR antigens was carried out on over 7,000 transplant donors and recipients at 8 participating laboratories. Approximately 25% of the individuals were found to have been typed incorrectly by serological means. An analysis of over 2,500 first cadaver kidney transplants showed a significant correlation of matching for the HLA-DR antigens in transplants where the serological typing was confirmed by DNA typing. In transplants where the serological typing was found to be incorrect, the analysis of serological HLA-DR mismatches resulted in no correlation with graft outcome whereas a significant correlation was found when the corrected DNA typed HLA-DR antigens were analyzed. Transplants which had been reported to the Collaborative Transplant Study based on serological typing as matched for HLA-A, -B, -DR or HLA-B, -DR were found to have a superior graft survival rate only if HLA-DR compatibility was confirmed by DNA typing.     

Consistency of assessment of adverse drug reactions in psychiatric hospitals: A comparison of an algorithmic and an empirical approach

Summary Within an ongoing drug surveillance project (AMÜP) in psychiatric hospitals, a comparative study was carried out to evaluate two methods commonly used in the field of adverse drug reaction assessment. Two raters, who have cooperated with the project since its inception, evaluated 80 randomly selected ADRs twice; first, by an empirical (implicit) approach, and second, 4 weeks later, by using an algorithm as proposed by Kramer et al. 1979. Agreement on medication and related probability ratings was obtained in 81% of all 80 cases for the empirical method (weighted Kappa=0.41), and in 69% for the algorithmic method (weighted Kappa=0.62), indicating that agreement exceeded chance for both methods. By comparison with assessments made in previous case conferences of the project, empirical ratings were found to be reliable over time due to homogeneous use of criteria by project raters. In contrast to the reports on the subject, agreement between raters appeared to be superior in the empirical method as compared to the algorithmic assessment. Analysis of disagreements suggested that probability ratings based on the empirical method were nonspecific, due to conventional criteria applied in the project. Inter-rater agreement was reduced by polypharmacy, especially in the case of algorithmic assessments. The consistency of assessment was also lowered by the fact that the 2 methods assigned different weights to particular assessment criteria.Dedicated to Prof. Dr. H. Kewitz, Head of the Department of Clinical Pharmacology, Klinikum Steglitz, Berlin (West), on the occasion of his 65th birthday     

Evaluation of the ability of glass-ionomer cement to bond to glass-ionomer cement

This study investigated the cohesive bond strengths of glass-ionomer cement at three setting and etching intervals and compared these bonds to the shear strength of the material itself. Bonded cylinders were created and then sheared using the Instron Universal Testing Machine. Analysis of bond values of glass ionomer added to glass ionomer indicate bond variability and low cohesive bond strength of the material. Bond values of unbonded glass-ionomer material indicate that the material itself is stronger than bonds established between bonded samples.     

Decrease of D2 receptors indicated by 123I-iodobenzamide single-photon emission computed tomography relates to neurological deficit in treated Wilson's disease.

Single-photon emission computed tomography with 123I-iodobenzamide, a dopamine D2 receptor antagonist, was employed to study dopamine D2 receptor densities in 17 patients with biochemically proved Wilson's disease and stable neurological status with therapy and in 5 age-matched control subjects. Of the 17 patients with Wilson's disease, 5 were neurologically asymptomatic, 3 had cerebellar signs, 1 exhibited a mild parkinsonian syndrome, 7 showed a parkinsonian syndrome and cerebellar signs, and 1 had generalized dystonia and a parkinsonian syndrome. In 5 age-matched control subjects specific isotope binding as calculated by the basal ganglia to frontal cortex ratio was 1.57 +/- 0.04 (mean +/- standard deviation). The ratio in patients with Wilson's disease ranged from 1.56 +/- 0.05 (n = 5, asymptomatic patients) to 1.17 +/- 0.02 (n = 4, marked neurological impairment). We observed an almost linear correlation between the reduction of 123I-iodobenzamide (IBZM) binding and the severity of neurological signs at the time of IBZM-SPECT (correlation coefficient, -0.84; p < 0.01). We suggest that the reduction of postsynaptic striatal dopamine D2 receptors as detected by IBZM-SPECT reflects striatal neuronal damage in Wilson's disease.