Estrogen replacement therapy and worsening of radiographic knee osteoarthritis: the Framingham Study

OBJECTIVE: To examine whether estrogen replacement therapy (ERT) prevents worsening of radiographic knee osteoarthritis (OA) in elderly women. METHODS: A total of 551 women ages 63-91 years (mean age 71) in the Framingham Study were followed up from biennial examination 18 (1983-1985) to examination 22 (1992-1993). Data on postmenopausal ERT were obtained every 2 years. Subjects were classified into 3 groups according to their estrogen use at biennial examination 18: never users (n = 349), past users (n = 162), and current users (n = 40). Women received anteroposterior weight-bearing knee radiographs at examinations 18 and 22. Using the Kellgren and Lawrence criteria, global radiographic knee OA was assessed, (grade range 0-4) and individual radiographic features, such as osteophytes and joint space narrowing, were scored from 0 to 3. Worsening was defined as either development of radiographic OA that was not present at baseline (incident OA) or progression of baseline radiographic OA by > or =1 Kellgren and Lawrence grade (progressive OA). Potential confounding factors included age, body mass index, weight change, smoking, knee injury, physical activity level, and bone mineral density at the femoral neck. RESULTS: During 8 years of followup, 17.4% of knee radiographic scores worsened by 1 grade and 5.8% by 2 or 3 grades among never users of ERT. Among current estrogen users, only 11.7% of knee radiographic scores worsened by 1 grade and none worsened by more than 1 grade. After adjusting for age and other potential confounding factors, the relative risk of incident radiographic knee OA in comparison with never users of estrogen was 0.8 (95% confidence interval [95% CI] 0.5-1.4) in past users and 0.4 (95% CI 0.1-3.0) in current users. Current use of estrogen also showed a trend toward decreased risk of progressive knee OA compared with never use (odds ratio [OR] 0.5, 95% CI 0.1-2.9). When both incident and progressive radiographic knee OA cases were combined, current ERT use had a 60% decreased risk compared with never use (OR 0.4, 95% CI 0.1-1.5). CONCLUSION: This is the first prospective cohort study to examine the effects of ERT on radiographic knee OA. The results indicate that current use of ERT had a moderate, but not statistically significant, protective effect against worsening of radiographic knee OA among elderly white women. These findings corroborate those of cross-sectional studies and point further to a potential benefit of female hormones in OA.     

Ultrasonic evaluation of gallbladder emptying with ceruletide: comparison to oral cholecystography with fatty meal

Assessment of gallbladder function is required prior to nonsurgical treatment of gallstones. In order to develop a practical and reproducible method of evaluation, gallbladder emptying was studied by ultrasound (US) in 55 gallstone patients after intramuscular administration of ceruletide (0.3 micrograms/kg). In 27 of these subjects, the US procedure was compared to oral cholecystography (OCG) with fatty meal. Maximal percent gallbladder contraction was reached 30 min after ceruletide in all patients. Maximal percent contractions were 47.5 +/- 27.7 during US with ceruletide and 33.9 +/- 16.3 during OCG with fatty meal (p = 0.03). A significant linear relationship was found between the results obtained with the two different procedures (r = 0.57; p = 0.002). Serial US determinations of gallbladder emptying were performed in 16 patients. Individual variation was below 20% in 11 subjects, and in five subjects it ranged between 20 and 40%. Minor, self-limiting side effects were observed in 13 patients. US determination of gallbladder emptying after ceruletide appears to be a practical and reliable method to assess gallbladder function.     

Visualization of the arteries, veins, and nerves of the orbit by sector computed tomography

Altering the scintillation crystal configuration of a fixed-detector CT scanner increased the spatial resolution from 6.25 to 10 line pairs per centimeter. Sector scans of th orbit with this modified scanner showed the ophthalmic artery and superior ophthalmic vein and their branches and the intraorbital branches of the third, fifth, and sixth nerves, apparently seen with CT for the first time.     

Accumulation and metabolism of uneven fatty acids present in single cell protein

Liquipron and Toprina, obtained by growing yeasts (Candida maltosa and Candida lipolytica) on n-hydrocarbons, were investigated to ascertain the biological significance and possible toxicological implications of their high content of uneven fatty acids (UFA). It was confirmed that the extent to which UFA accumulate in adipose tissue of rats fed the 2 products reflects only partially their UFA contents. The presence of UFA in rat tissues does not appear to alter intermediate metabolism. The capacity of liver mitochondria ot oxidize palmitic acid was similar in control and in Liquipron-treated rats. Palmitic acid and heptadecanoic acid did not compete for oxidation when mixed at concentrations which reflect their presence in the tissues of animals fed high levels of Liquipron.