Biomedical subjects

D C Miller

Publications and source records attributed to D C Miller.

421 records · Page 24Linked to original sources

PubMedDate not supplied

Structure and function of the rubella virus proteins.

Rubella virus strain HPV-77 contains three structural polypeptides. The nucleocapsid is constructed with the C polypeptide chain, which has a molecular weight of 30,000. The envelope proteins are constructed with two glycopolypeptides; the E1 glycopolypeptide has a molecular weight of 63,000, and the E2 glycopolypeptide has a molecular weight of 45,000-48,000. The nucleocapsid capsomere is approximately 6.2S, has a molecular weight of 130,000, and consists of two disulfide-linked dimers of the C polypeptide. The E1 and E2 glycopolypeptides are associated, but the size and structure of the spike protein have not been determined. Strain-specific antigens were detected within the E2 glycopolypeptide in all of the strains tested. In chronologic serum samples, the titers of antibody to the E2 and C polypeptides were the first to decline. Hybridomas were produced that exhibited hemagglutination-inhibiting and neutralizing activities; however, these functions did not always correlate. Both the hemagglutination-inhibiting and neutralizing antibodies reacted with the E1 glycopolypeptide.

Animals↗

PubMedDate not supplied

Atrophy of hippocampal formation subdivisions correlates with stage and duration of Alzheimer disease.

The hippocampal formations of 13 subjects with severe Alzheimer disease [AD; Global Deterioration Scale (GDS) stage 7] and of 5 age-matched subjects without symptoms of dementia were reconstructed from serial sections. Functional assessment staging (FAST) was used at the time of demise to assess 9 patients at stages 7a-c (incipient averbal and nonambulatory) and 4 patients at stages 7e-f (immobile). The duration of the disease from FAST stage 5 until demise ranged from 2 to 8 years in the first of these subgroups, and from 10 to 13 years in the second. The volumes of the entire hippocampal formation and of the cornu ammonis, its sectors and layers, the dentate gyrus, the subicular complex, and the entorhinal cortex were calculated. Hippocampal formation volume decreased by 36% in the incipient averbal and nonambulatory patients and by 60% in the severely functionally impaired immobile patients, in comparison with controls. In the final substages of AD, immobile patients exhibited significant atrophy, in comparison with controls, in the cornu ammonis and all of its sectors and layers except CA4, the subicular complex and all of its parts, and the entorhinal cortex (p < 0.05). Within the AD patient group, significant correlations were noted between both the magnitude of functional severity and the duration of AD and the volumes of most hippocampal formation subdivisions studied. For the cornu ammonis, subicular complex, and entorhinal cortex, volumetric loss correlations with FAST stage 7 ordinally enumerated substages were r = -0.71, -0.79, and -0.62, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMedDate not supplied

Regional variability of prostacyclin biosynthesis.

To investigate the regional variability in arterial and venous endothelial prostacyclin (PGI2) biosynthesis, we obtained 1-cm segments of carotid arteries, external jugular veins, femoral arteries and veins, iliac arteries and veins, inferior venae cavae (IVC), and aortas from 17 dogs. Vessel luminal PGI2 production was measured in the basal state by radioimmunoassay of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha). A total of 90 arterial specimens (57, 19, and 14 segments, respectively, of femoral/carotid arteries, iliac arteries, and aorta) and 41 venous specimens (15, 10, and 16 segments, respectively, of femoral/jugular veins, iliac veins, and IVC) were analyzed. Overall, arterial endothelial 6-keto-PGF1 alpha was higher than venous (8.1 +/- 0.5 ng/ml vs. 4.9 +/- 0.7 ng/ml, p less than 0.0004); 6-keto-PGF1 alpha levels were greater in the arteries than in their corresponding veins [femoral/carotid arteries (6.3 +/- 0.4 ng/ml) vs. femoral/jugular vein (2.1 +/- 0.4 ng/ml), p less than 0.0002; iliac arteries (9.3 +/- 1.0 ng/ml) vs. iliac veins (4.8 +/- 0.9 ng/ml), p less than 0.005; aorta (14.0 +/- 1.6 ng/ml) vs. IVC (7.5 +/- 1.4 ng/ml), p less than 0.006].(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗

PubMedDate not supplied

NMR-neuropathologic correlation in stroke.

True, three-dimensional proton nuclear magnetic resonance imaging at 0.147 tesla was performed postmortem on 2 patients embodying various stroke syndromes, including chronic (4 and 15 years) infarction, subacute (within 1 week) bland infarction, acute (2 days) hemorrhagic infarction, and hematoma secondary to ruptured aneurysm. A third patient, with subcortical arteriosclerotic encephalopathy, so-called Binswanger's disease, was examined antemortem using a 0.6 tesla scanner. Nuclear magnetic resonance images were reconstructed at levels matching the pathologic specimens. Qualitative and, when available, quantitative comparisons between the results of nuclear magnetic resonance imaging and pathology were carried out. Areas of qualitatively prolonged T1 and T2 relaxation times on nuclear magnetic resonance imaging were more extensive than the corresponding areas of chronic infarction noted pathologically and were determined to be infarcts plus the adjacent areas of Wallerian degeneration. Hemorrhagic infarction, without evidence of blood on computed tomography, was found to have mildly prolonged T1 and T2 relaxation times, between those of normal brain and chronic infarction; a 10-day-old hematoma had a very short T1, slightly shorter than that of white matter, and a mildly prolonged T2, with values between those of white and gray matter. Subcortical arteriosclerotic encephalopathy was found to have areas of prolonged T1 and T2 relaxation times involving almost the entire white matter of the corona radiata.

Acute Disease↗

PubMedDate not supplied

Lung adenocarcinomas metastatic to the brain with and without ultrastructural evidence of rootlets: an electron microscopic and immunohistochemical study using cytokeratins 7 and 20 and villin.

Adenocarcinomas metastatic to brain from lung or colon may pose differentiation difficulties. Ultrastructurally, both may have brush borders with rootlets. This study examines the ultrastructural morphology and immunohistochemical expression of villin (associated with rootlets), cytokeratin 7 (present in lung adenocarcinomas), and cytokeratin 20 (present in colon adenocarcinomas) in 19 formalin-fixed sequential surgical biopsies of lung adenocarcinomas metastatic to brain as compared to 13 colonic adenocarcinoma metastases. Of lung tumor metastases, mucinous differentiation with rootlets was most common [6/19(32%)]. All colon tumor metastases were cytokeratin 7(-), 20(+), and profusely villin(+). Well-formed rootlets were seen. All lung metastases were cytokeratin 7(+) and 20(-). 5/6(83%) lung metastases with rootlets were focally villin(+). 12/13(95%) without rootlets were villin(-). Rootlets are extremely common in lung adenocarcinoma metastatic to brain. Villin immunoreactivity closely correlates with rootlets. Its distribution is a useful adjunct to cytokeratin 7 and 20 in differentiation of lung versus colon adenocarcinomas metastatic to the brain.

Adenocarcinoma↗

PubMedDate not supplied

Effects of fish oil on graft arteriosclerosis and MHC class II antigen expression in rat heterotopic cardiac allografts.

The effect of fish oil on accelerated graft coronary arteriosclerosis was assessed in Lewis to Brown-Norway rat heterotopic cardiac allografts. Twelve Brown-Norway rats were supplemented with 2 ml/kg/day of fish oil (68.3 mg eicosopentaenoic acid and 47.5 mg decosahexaenoic acid per milliliter). Eleven additional animals, receiving an isocaloric amount of safflower oil, served as control. All diets began 1 week before operation. Immunosuppression was obtained with low-dose cyclosporine (2 mg/kg/d). When killed (100 days), there were no significant differences in percentage weight gain, graft function, or histologic rejection score. Although lipid profiles were comparable, total cholesterol:high-density lipoprotein ratio was marginally higher in animals treated with fish oil (p = 0.069). Mean percentage luminal occlusion (before and after correcting for differences in size between coronary vessels analyzed) and average intimal thickness were similar between animals treated with fish oil and safflower oil as assessed by computer-assisted digitized, morphometric planimetry. In all allografts, donor interstitial dendritic cells were repopulated with recipient dendritic cells. The major histocompatibility complex class II cell density in the fish oil group did not differ significantly from rats supplemented with safflower oil (1.48 +/- 0.68 vs 1.48 +/- 0.65 cells per mm2, p = 0.995). In conclusion, fish oil did not exert any beneficial effect over safflower oil in terms of graft coronary arteriosclerosis, histologic rejection, or plasma lipids.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMedDate not supplied

CT diagnostic features of Alzheimer disease: importance of the choroidal/hippocampal fissure complex.

Neuropathologic changes in the temporal lobe, including focal atrophy of the subiculum and entorhinal cortex, have been described in association with Alzheimer disease. We studied the usefulness of detecting temporal-lobe structural changes on CT in making the diagnosis of Alzheimer disease. The dementia imaging protocol we use includes thin-section (5 mm) cuts of the temporal lobe oriented 20 degrees negative (caudal) to the plane of the canthomeatal line. Thirty-four patients with suspected Alzheimer disease and 20 normal elderly control subjects, all between 65 and 80 years old, were studied with a standard protocol that also included neurologic and medical examinations and detailed psychometric testing. All the temporal-lobe evaluations of the five variables measured were significantly associated with the presence or absence of Alzheimer disease. Almost all Alzheimer patients showed evidence of mild or greater severity of overall temporal-lobe atrophy. The absence of temporal-lobe atrophy, seen in approximately one half the normal cases, identified normal individuals with a high degree of specificity (95%). The presence of characteristic hippocampal lucency, apparently due to enlargement of the choroid and hippocampal fissures, showed the highest sensitivity and classification accuracy of all the variables tested (82 and 80% respectively; p less than .001), correctly identifying 82% of Alzheimer patients and 80% of Alzheimer patients and control subjects. These results indicate that CT detection of structural changes in the temporal lobe and hippocampus strongly support the diagnosis of Alzheimer disease. A temporal-lobe imaging protocol for CT, and by extension for MR, is suggested for the evaluation of patients with the clinical diagnosis of a dementing disorder.

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