Carotenoid, tocopherol, and retinol concentrations in elderly human brain.

BACKGROUND: Antioxidants, such as tocopherols and carotenoids, have been implicated in the prevention of degenerative diseases. Although correlations have been made between diseases and tissue levels of antioxidants, to date there are no reports of individual carotenoid concentrations in human brain. OBJECTIVE: To measure the major carotenoids, tocopherols, and retinol in frontal and occipital regions of human brain. DESIGN: Ten samples of brain tissue from frontal lobe cortex and occipital cortex of five cadavers were examined. Sections were dissected into gray and white matter, extracted with organic solvents, and analyzed by HPLC. RESULTS: At least 16 carotenoids, 3 tocopherols, and retinol were present in human brain. Major carotenoids were identified as lutein, zeaxanthin, anhydrolutein, alpha- cryptoxanthin, beta- cryptoxanthin, alpha-carotene, cis- and trans-betacarotene, and cis- and trans-lycopene. Xanthophylls (oxygenated carotenoids) accounted for 66-77% of total carotenoids in all brain regions examined. Similar to neural retina, the ratio of zeaxanthin to lutein was high and these two xanthophylls were significantly correlated (p <0.0001). The tocopherol isomers occurred in the brain over a wider range of mean concentrations (0.11-17.9 nmol/g) than either retinol (87.8 - 163.3 pmol/g) or the identified carotenoids (1.8-23.0 pmol/g). CONCLUSIONS: The frontal cortex, generally vulnerable in Alzheimer's disease, had higher concentrations of all analytes than the occipital cortex which is generally unaffected. Moreover, frontal lobes, but not occipital lobes, exhibited an age-related decline in retinol, total tocopherols, total xanthophylls and total carotenoids. The importance of these differences and the role(s) of these antioxidants in the brain remain to be determined.

Growth and histopathology of human head and neck squamous cell carcinoma implanted intraorally in nude mice.

A human squamous cell carcinoma (SCC) from the floor of the mouth (FOM) was implanted by a needle aspiration technique in the FOM site of athymic nude mice. Mice were killed at 3-week intervals, and the oral cavity, mandible, and neck were sectioned and examined histologically. Tumor growth was observed in 65% of the animals, with histologic features consistent with the engrafted human invasive SCC. These features included invasion of connective tissue in 92%, invasion of muscle in 77%, invasion and destruction of bone in 54%, and vascular invasion in 15% of the mice. In contrast, FOM tumor implanted subcutaneously on back sites of nude mice was totally encapsulated by fibrous connective tissue with evidence of capsular invasion. SCC from other head and neck sites showed similar locally invasive growth after intraoral implantation in nude mice. The results demonstrate the invasive characteristics of human head and neck SCC grown in the homologous oral cavity site in nude mice and support the nude mouse as a biologically relevant in vivo model in the investigation of the biologic characteristics and therapy of head and neck carcinoma.

Evaluation of micrometric and microdensitometric methods for measuring the width of retinal vessel images on fundus photographs.

The width of retinal vessel images on fundus photographs was determined by projection micrometry and microdensitometry. These methods were evaluated on 12 retinal vessels using the negatives of 570-nm monochromatic fundus photographs. For projection micrometry, the intraobserver reproducibility of vessel width measurements was 1.6%-2.9%, depending upon the experience of the observer. Significant interobserver differences in the measured widths were demonstrated. For microdensitometry, three distinct measurement criteria were used. Significant differences in width as measured by the three criteria were found, but there were no interoperator differences for each criterion. The intraoperator reproducibility of vessel width measurements by microdensitometry was 2.1%-2.5%. Significant differences were found in the vessel widths determined by the micrometry and densitometry methods, and results obtained by micrometry are discussed in terms of edge-detection phenomena.

Retinal pigment epithelial lipofuscin and melanin and choroidal melanin in human eyes.

Optical measurements of the pigments of the retinal pigment epithelium (RPE) and choroid were made on 38 human autopsy eyes of both blacks and whites, varying in age between 2 wk and 90 yr old. Lipofuscin in melanin-bleached RPE was measured as fluorescence at 470 mm following excitation at 365 nm and was found to be proportional to fluorescence measured at 560 nm in unbleached tissue. Transmission measurements of RPE and choroidal melanin were converted and expressed as optical density units. The choroidal melanin content increased from the periphery to the posterior pole. RPE melanin concentration decreased from the periphery to the posterior pole with an increase in the macula. Conversely, the amount of RPE lipofuscin increased from the periphery to the posterior pole with a consistent dip at the fovea. There was an inverse relationship between RPE lipofuscin concentration and RPE melanin concentration. The RPE melanin content was similar between whites and blacks. Lipofuscin concentration was significantly greater (P = 0.002) in the RPE of whites compared to blacks; whereas blacks had a significantly greater (P = 0.005) choroidal melanin content than whites. The amounts of both choroidal and RPE melanin showed a trend of decreasing content with aging, whereas the amount RPE lipofuscin tended to increase (whites greater than blacks). Per fundus area, the amount of choroidal melanin was always greater than that in the RPE. There was a statistically significant (P = 0.001) increase in RPE height with age, most marked in eyes of whites after age 50 and correlated with the increase in lipofuscin concentration.

Relationship of senile macular degeneration to ocular pigmentation.

We prospectively evaluated 650 consecutive white patients with senile macular degeneration and compared them to a control group of 363 patients. Ocular pigmentation (iris color and fundus pigmentation) was recorded for each patient, as was hair color (as a child and young adult) and age at evaluation. Patients were from the New England states and Florida. Our most significant finding was that 494 patients with senile macular degeneration (76%) had light-colored irides compared with 145 of the controls (40%). Fundus pigmentation closely corresponded to iris pigmentation (P less than 0.01). Hair color was blond or light brown in 370 of the patients with senile macular degeneration (57%) and in 105 of the controls (29%). Further, there was a tendency for individuals with lightly pigmented irides to have senile macular degeneration at an earlier age than those with dark irides (P less than .01). Thus, increased ocular pigmentation tends to decrease the risk of developing senile macular degeneration.

Hepatic oxygen supply during early and late sepsis in the rat.

Hepatic oxygen supply and related parameters were evaluated during early (8-10 h) and late (18-26 h) stages of lethal septic peritonitis induced in rats by cecal ligation and puncture. In the early phase, hepatic pO2 was reduced significantly (mean 9.3 versus 22.2 mmHg in sham-operated controls). This was accompanied by elevations of serum glutamic oxaloacetic transaminase and glutamic pyruvic transaminase (p less than 0.02 and p less than 0.10, respectively), and increased hematocrit (p less than 0.001). Total body oxygen consumption was decreased by 19% (p less than 0.001). By the late stage of sepsis, hepatic oxygen supply was depressed profoundly (mean 2.0 versus 24.5 mmHg in controls) concomitant with further elevations of serum transaminases. Lactacidemia, respiratory alkalosis, and tachycardia were also present. Hypoxemia and hypotension were not observed during either early or late stages. Our results may be interpreted as representing early and progressive impairment of hepatic oxygen delivery in rats subjected to cecal ligation and puncture.

Housekeeping: customized training program keyed to hospital's procedures, staff.

Thoughtfully developed, conscientiously applied housekeeping employee training programs are all too scarce. The program described was customized to fit an individual hospital's standard procedures, and it used volunteer models from among the workers to illustrate the video portion of the program. Recognition of employee merit and effective supervision and follow-up were two other key elements.