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J Greene

Publications and source records attributed to J Greene.

At least 667 records · Page 37Linked to original sources
PubMed1990

Effect of advanced age on p-aminohippurate-induced inhibition of renal tubular secretion in male Fischer 344 rats.

The effect of aging on glomerular filtration, effective renal plasma flow and on the responsiveness of the renal tubular anion secretory system to inhibition by 4-aminobenzoylglycine (p-aminohippurate, PAH) was examined in young (5-month) and old (22-month) Fischer 344 male rats. Plasma clearance, protein binding and renal extraction of [131I]o-iodohippurate, [125I]iothalamate and HPLC-purified [99mTc]mercaptoacetyltriglycine (MAG3), were used as in vivo probes of renal function. The effect of advanced age, without concomitant PAH, on the disposition of these markers was initially determined in ketamine anesthetized, temperature-maintained male rats, ages 5, 14 and 22 months by means of constant infusion clearance studies. Aging per se decreased (P less than 0.05) the kidney-weight normalized or body weight-normalized GFR and effective renal plasma flow rates. GFR values averaged 1.67, 1.43 and 1.32 ml/min per g kidney for the 5-, 14- and 22-month-old rats, respectively. Kidney- or body weight-normalized clearances of MAG3 and o-iodohippurate showed similar (25-27%) decreases, whereas the absolute values (ml/min) for GFR, o-iodohippurate and MAG3 clearance rates were not altered by aging. The effective filtration fraction, extraction ratio and plasma protein binding were also unchanged by advanced age. Overall, the age-related decreases in renal function were minimal in Fischer-344 rats, compared to other species. Differences in data normalization, species and gender account, in part, for discrepancies observed when comparing results in different studies on the effects of advanced age on renal function. Subsequently, we examined the effect of aging on the renal responsiveness to inhibition of tubular anion secretion using constant rate PAH infusion studies, adjusted for age-related changes in renal function. Aging did not alter PAH-induced inhibition of iodohippurate secretion. Inhibition of MAG3 elimination was more pronounced in the old rats compared to the young controls.

Aging↗
PubMed1990

Oral mucosal lesions found in smokeless tobacco users.

The risk for oral mucosal lesions associated with use of smokeless tobacco among 1,109 professional baseball players during spring training in 1988 was investigated. Leukoplakia was very strongly associated with use of smokeless tobacco in this population of healthy young men. Of the 423 current smokeless tobacco users, 196 had leukoplakia compared to seven of the 493 nonusers (OR = 60.0, 95% CI = 40.5-88.8). The amount of smokeless tobacco used (in hours per day that smokeless tobacco was held in the mouth), recency of smokeless tobacco use (hours since last use), type (snuff versus chewing tobacco), and brand of snuff used were significantly associated with risk for leukoplakic lesions among smokeless tobacco users. Ninety-eight leukoplakic areas in 92 subjects were biopsied and examined microscopically. All lesions were benign, but one specimen had mild epithelial dysplasia. The long-term significance of leukoplakia in smokeless tobacco users and their relation to oral cancer is not clear.

Adult↗
PubMed1990

Periodontal effects associated with the use of smokeless tobacco.

This report describes periodontal findings from a comprehensive study of smokeless tobacco use in professional baseball players. Subjects consisted of 1,094 players, coaches, and training staff of seven major league and their associated minor league teams. Before being examined, subjects completed questionnaires on patterns of smokeless tobacco use (validated by blood chemistry studies), rinsed their mouths under supervision, and were cautioned not to discuss their use of tobacco with the dental examiners. They then received a complete oral examination that included recording of all mucosal abnormalities, missing teeth, caries, extrinsic stain, attrition, Plaque Index, Gingival Index, pocket depth, attachment loss, and gingival recession. More than 50% of team members reported using smokeless tobacco, and 39% reported use during the current week. Among current week users, 46% had oral mucosal lesions, located primarily in the mandible at sites where the smokeless tobacco quid was placed. The use of smokeless tobacco was not necessarily associated with severe forms of periodontal disease, and the presence of poor oral hygiene and gingivitis in these users was not related to the development of oral lesions. However, sites adjacent to mucosal lesions in smokeless tobacco users showed significantly greater recession and attachment loss than in sites not adjacent to lesions in users or comparable sites in non-users.

Adult↗
PubMed1990

Nocardia brasiliensis cellulitis in a heart transplant patient.

Three months after undergoing heart transplantation, a 55-year-old man presented with N. brasiliensis cellulitis resulting from a splinter wound acquired during yard work. Surgical débridement was necessary before the infection responded to medical treatment. Although pulmonary nocardiosis is a well-documented complication of immunosuppressive therapy, this is the 1st report of a nocardial infection associated with primary skin involvement in a heart transplant patient.

Journal Article↗