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Biomedical subjects

J Sheldon

Publications and source records attributed to J Sheldon.

90 records · Page 5Linked to original sources

MRI assisted treatment planning for radiation therapy of the head and neck.

Improved visualization of head and neck tumors has been demonstrated with the use of magnetic resonance imaging (MRI). Using standard plastic radiation therapy immobilization casts and an MR positive surface marker system developed in this institution, we have utilized MRI as an adjunct to the simulation of complex radiation treatments for tumors of the head and neck. This technique includes an indirect display of field margins and/or isodose curves over selected MR images. The lack of induced artifact from the immobilization cast, improved delineation of tumor extension from normal anatomy and the ability to image in arbitrary planes without changing patient positioning favor the use of MR over CT for radiation therapy planning in the head and neck, while ensuring reproducibility of the treatment plan at subsequent therapy sessions.

Aged↗

Glycosylated hemoglobins and glycosylated plasma proteins in the diagnosis of diabetes mellitus and impaired glucose tolerance.

Total and stable glycosylated hemoglobins and glycosylated plasma proteins were determined on 53 patients referred for a glucose tolerance test. Significant correlations were found with fasting blood glucose (r greater than 0.89), 2-h glucose (r greater than 0.69), and area under the glucose tolerance curve (r greater than 0.75), but the correlations with labile glycosylated proteins were not significant. Thirty-one of the patients were normal, five had impaired glucose tolerance (IGT), and seventeen diabetes mellitus (DM) according to the WHO criteria. Comparison of the glycosylated protein values showed that, in all cases, the values for those with IGT and DM were significantly (P less than 0.001) greater than the values for normals. The range of values of stable glycosylated hemoglobins for those with DM (9.4-24.4%), those with IGT (8.6-10.0%), and normals (5.0-8.5%) shows that there was no overlap between overt diabetic subjects and normal subjects. This was also found for total glycosylated hemoglobins. The results for glycosylated plasma proteins, total and stable, were comparable, but one patient with overt DM and two with IGT had values within the normal range. The measurement of glycosylated hemoglobins and glycosylated plasma proteins by the simple, precise, affinity-chromatography method is potentially a quick, accurate, and simple screening test for patients with DM and IGT and deserves consideration as criteria for their diagnosis.

Blood Glucose↗

Seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8 in several regions of Italy.

OBJECTIVE: To study the seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus type 8 (KSHV/HHV-8) in 779 Italian blood donors. STUDY DESIGN/METHODS: Sera were tested for antibodies to a latency-associated nuclear antigen (LANA) and a capsid related protein encoded by ORF65. RESULTS: Among all Italian donors, 17.7% and 18.7% had antibodies to LANA and ORF65 protein, respectively, and 24.1% had antibodies to at least one antigen. KSHV/HHV-8 seroprevalence was higher in the Po valley and in Sardinia than close to the sub-Alpine Veneto region, Tuscany, or Apulia. KSHV/HHV-8 seroprevalence was almost equally distributed between men and women but increased in the older age groups. CONCLUSIONS: The regional differences and age distribution in seroprevalence agree partially with the incidence of classic KS in Italy. The rarity of classic KS in KSHV/HHV-8-infected subjects and the equal gender distribution of seroprevalence suggest that other cofactors may contribute to KS development in human immunodeficiency virus type 1 (HIV-1)-uninfected individuals.

Adolescent↗

MR signal abnormalities in memory disorder and dementia.

MR imaging of the brain, performed in 86 normal subjects and 113 patients with objective memory disorder or dementia, demonstrated white- and gray-matter areas of high signal intensity on long TR images (short and long TE). Hyperintensities were analyzed with respect to size (on a scale of 0-3) and location: lesions were periventricular, subcortical, or cortical. The patients with memory disorder and dementia were categorized as having probable/possible Alzheimer disease, a combination of Alzheimer disease and multiinfarct cognitive disorder, or multiinfarct cognitive disorder alone on the basis of clinically determined Hachinski ischemic scores. Significant correlations were found between age and scores for periventricular lesions (r = .40, p less than .0005) and subcortical lesions (r = .39, p less than .0005) in normal subjects. Correlations were also found between the Hachinski ischemic score and scores for periventricular lesions (r = .21, p less than .01), subcortical lesions (r = .27, p less than .0002), and cortical lesions (r = .32, p less than .0005) in subjects with memory disorder/dementia. Comparing multiinfarct cognitive disorder, Alzheimer disease, and normal groups, the mean scores for periventricular lesions were 12.0 +/- 4.6, 7.6 +/- 4.8, and 3.4 +/- 2.6, while mean scores for subcortical lesions were 10.8 +/- 12.2, 4.1 +/- 6.4, and 0.8 +/- 1.2, respectively. Periventricular lesions were present in 99-100% of patients with Alzheimer disease and multiinfarct cognitive disorder. On the other hand, subcortical lesions, which were identified in 100% of patients with multiinfarct cognitive disorder, were present in only about half of the patients with Alzheimer disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗