Carcinogenesis studies of benzophenone in rats and mice.

Benzophenone, an aryl ketone, is used primarily as a photoinitiator and fragrance enhancer. Groups of 50 male and 50 female F344 rats and B6C3 F1 mice were fed diets containing 0, 312, 625, and 1250 ppm benzophenone for 105 weeks. Survival of males exposed to 1250 ppm benzophenone was significantly less than that of controls. There was a positive trend in the incidence of renal tubule adenoma in male rats; these neoplasms were accompanied by significantly increased incidences of renal tubule hyperplasia. Increased incidences of mononuclear cell leukemia were observed in male rats exposed to 312 or 625 ppm benzophenone and in female rats exposed to 625 ppm benzophenone. Liver lesions observed included significantly increased incidences of hepatocytic centrilobular hypertrophy in all exposed groups of rats. In mice, survival of all exposed groups was generally similar to that of the control groups. In male mice, there were significantly increased incidences of hepatocellular adenoma in the 625 and 1250 ppm groups. In female mice, the incidences of hepatocellular adenoma in the 625 and 1250 ppm groups were higher than expected after adjusting for the lower body weights in these groups. The incidences of kidney nephropathy in exposed groups of female mice, as well as the severity of nephropathy in exposed groups of males, were significantly increased. The incidences of metaplasia of the olfactory epithelium were significantly increased in 1250 ppm mice. Rare histiocytic sarcomas were observed in female rats and mice in the 625 and 1250 ppm groups. Under the conditions of these 2-year studies, there was some evidence of carcinogenic activity of benzophenone in male F344/N rats based on increased incidences of renal tubule adenoma. There was equivocal evidence of carcinogenic activity of benzophenone in female F344/N rats based on the marginal increased incidences of mononuclear cell leukemia and histiocytic sarcoma. There was some evidence of carcinogenic activity of benzophenone in male B6C3F(1) mice based on increased incidences of hepatocellular neoplasms, primarily adenoma. There was some evidence of carcinogenic activity of benzophenone in female B6C3F(1) mice based on increased incidences of histiocytic sarcoma; the incidences of hepatocellular adenoma in female B6C3F(1) mice may have been related to benzophenone exposure.

Absence of toxic effects in F344/N rats and B6C3F1 mice following subchronic administration of chromium picolinate monohydrate.

Chromium picolinate monohydrate (CPM) is a synthetic compound heavily marketed to consumers in the United States for use as a dietary supplement for muscle building and weight loss. The National Toxicology Program (NTP) tested the toxicity of this compound based on the potential for widespread consumer exposure and lack of information about its toxicity. Groups of 10 male and 10 female F344/N rats and B6C3F(1) mice were exposed to 0, 80, 240, 2000, 10,000, or 50,000 ppm CPM in feed for 13 weeks. CPM administration produced no effect on body weight gain or survival of rats or mice. Organ weights and organ/body weight ratios in exposed animals were generally unaffected by CPM. No compound-related changes in hematology and clinical chemistry parameters were observed. There were no histopathological lesions attributed to CPM in rats or mice.

The impact of physical therapy on nursing home patient outcomes.

The objective of this retrospective study was to assess the intensity and outcome of individual components of interdisciplinary care, including physical therapy, in a teaching nursing home. Two independent reviewers abstracted records from 90 consecutive patients admitted to the nursing home. They rated intensity and outcome of each program component using a structured, standardized data-abstraction form. Program components were physical therapy, speech therapy, psychosocial therapy, medication adjustment, and other medical and nursing care. Physical therapy and medication adjustment were the most frequently received therapies. Eighty-eight percent of the patients receiving high-intensity physical therapy and 33% of the patients receiving moderate-intensity physical therapy improved. For medication adjustment, 93% and 72% of the high- and moderate-intensity groups, respectively, improved. In univariate analyses, physical therapy intensity and age were associated with improvement. Baseline function in activities of daily living and cognitive function were not associated with physical therapy outcome. A stepwise multiple logistic regression analysis revealed that only therapy intensity was associated with improved outcome. We conclude that physical therapy was efficacious for patients receiving high-intensity treatment. Advanced age, activities-of-daily-living status, and cognitive impairment were not associated with poor physical therapy outcome.

Hearing screening in the newborn intensive care nursery: comparison of methods.

Patients in the neonatal intensive care unit were tested by hearing screening tests including auditory brain stem response (ABR), transient and distortion-product otoacoustic emissions (TEOAEs and DPOAEs), and acoustic stapedius reflex (ASR), and by middle ear function tests including multifrequency tympanometry and pneumatic otoscopy. Pass rates on hearing tests were 75% to 89%. TEOAEs produced the lowest pass rate, and DPOAEs the highest. TEOAE, DPOAE, or ASR testing followed by ABR testing of initial failures produced pass rates of about 90%. The most efficient combination was DPOAEs followed by ABR. Pass rates tended to decrease with age. Of patients who failed 226-Hz and 678-Hz tympanometry, 30% to 67% passed hearing tests, suggesting a high false-positive rate for these immittance tests. The 3 ears that failed the 1000-Hz tympanogram failed all hearing tests. Many ears were abnormal by pneumatic otoscopy but passed hearing tests, suggesting that the usual ear examination criteria may not apply to infants.

Quality-of-life changes and hearing impairment. A randomized trial.

OBJECTIVE: To assess whether hearing aids improve the quality of life of elderly persons with hearing loss. SETTING: Primary care clinics at a Bureau of Veterans Affairs hospital. PATIENTS: One hundred and ninety-four elderly veterans who were identified as being hearing impaired from a screening survey involving 771 consecutive clinic patients. Of the original 194, 188 (97%) completed the trial. INTERVENTION: Subjects were randomly assigned to either receive a hearing aid (n = 95) or join a waiting list (n = 99). MAIN ENDPOINTS: A comprehensive battery of disease-specific and generic quality-of-life measures were administered at baseline, 6 weeks, and 4 months. MEASUREMENTS AND MAIN RESULTS: Persons assigned to the two groups were similar in age, ethnicity, education, marital status, occupation, and comorbid diseases. At baseline, 82% of subjects reported adverse effects on quality of life due to hearing impairment, and 24% were depressed. At follow-up, a significant change in score improvements for social and emotional function (34.0; 95% CI, 27.3 to 40.8; P less than 0.0001), communication function (24.2; CI, 17.2 to 31.2; P less than 0.0001), cognitive function (0.28; CI, 0.08 to 0.48; P = 0.008), and depression (0.80; CI, 0.09 to 1.51; P = 0.03) was seen in subjects who received hearing aids compared with those assigned to the waiting list. Six drop-outs (three per group), no crossovers, and no significant changes in cointerventions were seen. Average, self-reported, daily aid use in the hearing aid group was 8 hours. CONCLUSION: Hearing loss is associated with important adverse effects on the quality of life of elderly persons, effects which are reversible with hearing aids.