Selenium deficiency causes a number of hepatic metabolic alterations in the rat which could lead to changes in chemical toxicity. It causes a decrease in glutathione peroxidase activity, an increase in glutathione S-transferase activity, and an increase in the rate of glutathione synthesis. The hepatotoxicities of three compounds which bind to glutathione S-transferase; iodipamide, acetaminophen, and aflatoxin B1, are decreased by selenium deficiency. The toxicity of redox cycling compounds is generally increased by selenium deficiency and is accompanied by evidence of lipid peroxidation. Thus, nitrofurantoin (100 mg/kg) causes renal tubular necrosis in selenium-deficient rats but not in controls. Selenium-deficient rats are much more sensitive to diquat toxicity than are controls. Lethality of diquat in selenium-deficient rats appears to be causally linked to lipid peroxidation. Lethality of diquat in control rats is not linked to lipid peroxidation. The effect of selenium does not appear to be mediated by glutathione peroxidase, however, indicating that selenium has another oxidant defense function. Another interesting observation made was that increases in inspired O2 tension decreased ethane production (lipid peroxidation) in selenium-deficient and in control rats given diquat. Thus, O2 appears to prevent diquat-induced lipid peroxidation.

Acetaminophen↗

PubMedDate not supplied

Postradiation osteosarcoma of the spine following treatment of Hodgkin's disease.

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Combined Modality Therapy↗

PubMedDate not supplied

Progressive coxa valga after childhood excision of the hip abductor muscles.

To our knowledge, progressive coxa valga, femoral anteversion, and hip subluxation after surgical resection of soft tissue tumors of the gluteal muscles have not been described. The importance of this paper is to document proximal femoral deformity and hip subluxation in children after tumor resection of the hip abductor muscles, to provide guidelines for diagnosis and management of this problem, and to avoid late complications of progressive joint incongruity. Late deformity was seen in two cases after limb salvage surgery for a soft tissue buttock tumor. In both cases, the gluteus medius and minimus muscles were completely resected and the tensor fascia lata and gluteus maximus were partially resected. The ages of the patients at initial treatment were 4 months old and 5 years old, and both patients were followed for a minimum of 4 years. Valgus deformity was seen as early as 15 months. One patient has had a varus osteotomy to correct severe coxa valga and hip subluxation; the other patient with moderate deformity is being followed clinically and radiographically.

Bone Diseases, Developmental↗

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Estrogen affects the cellular metabolism of the anterior cruciate ligament. A potential explanation for female athletic injury.

Investigations from this laboratory have established the presence of estrogen receptors in the human anterior cruciate ligament. This study further investigates the effects of 17 beta-estradiol on the cellular proliferation and collagen synthesis of fibroblasts derived from the rabbit anterior cruciate ligament. Fibroblast proliferation and collagen synthesis in response to near log concentrations of 17 beta-estradiol (at 0.0029, 0.025, 0.25, 2.5, and 25 ng/ml) were assessed by measuring [3H]thymidine and [14C]hydroxyproline incorporation, respectively. Collagen synthesis was significantly reduced with increasing local estradiol concentration (P < 0.001). Declining collagen synthesis was first noted at a 17 beta-estradiol concentration of 0.025 ng/ml. Within normal physiologic levels of estrogen (0.025 to 0.25 ng/ml), collagen synthesis was reduced by more than 40% of control, and at pharmacologic levels of 2.5 and 25 ng/ml, by more than 50% of control. A significant reduction of fibroblast proliferation was also observed with increasing estradiol concentrations (P = 0.023). Clinically, alterations in anterior cruciate ligament cellular metabolism caused by estrogen fluctuations may change the composition of the ligament, rendering it more susceptible to injury.

Animals↗

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Routine vaginal cuff smear testing in post-hysterectomy patients with benign uterine conditions: when is it indicated?

BACKGROUND: By the age of 60 years, an estimated 33% of women will have undergone a hysterectomy. Approximately 85% of these hysterectomies are performed for benign disease. The object of this study was to evaluate cytologic findings from vaginal cuff smears in patients who have undergone hysterectomy for benign uterine conditions. METHODS: We conducted a community-based retrospective study and follow-up of women with vaginal cuff cytologic smears who had had a hysterectomy for benign uterine conditions. A total of 220 women were randomly selected who had one or more vaginal cuff smears. The main outcomes measures were invasive carcinoma, dysplastic lesions, and infections detected by vaginal cuff smear testing. The setting was a large inner-city hospital. RESULTS: Ninety-seven percent of 220 women who underwent hysterectomy for benign uterine conditions and who were observed for an average of 89 months had no cytologic abnormalities on vaginal cuff smears. Cytologic evaluation found no invasive carcinomas. Dysplastic lesions were detected in 7 patients (3%). Seventy percent of patients (n = 154) had one or more infections; these infections included bacterial vaginosis (106), trichomoniasis (95), candidiasis (40), koilocytosis suggestive of human papilloma virus (HPV) infection (3), and cytopathic effect of herpes (4). The prevalence of koilocytosis was much higher in the patients with dysplasia (P = .0003). CONCLUSIONS: Most routine vaginal cuff cytology screening tests need not be performed in women who have had a hysterectomy for benign uterine conditions.

Adult↗

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New opportunities for enhancing oral health: moving toward the 1990 objectives for the nation.

In July 1983, the Assistant Secretary for Health reviewed progress toward achievement of a dozen national objectives in fluoridation and dental health. These 12 objectives, classified under the categories of improved oral health status, reduced risk factors, increased public and professional awareness, improved services and protection, and improved surveillance-evaluation systems, hold promise for improved oral health in this country. It is noteworthy that the objective that 40 percent of 9-year-old children be caries-free in their permanent dentition has been accomplished (51 percent of 9-year-olds were caries-free according to a 1979-80 National Institute of Dental Research study). Still, dental caries is highly prevalent among teenaged children, and gingival and periodontal conditions are highly prevalent among children and adults. A number of highly effective methods are available for preventing dental decay in children as well as adults; they include community or school water fluoridation, the use of multiple forms of supplemental fluorides, avoidance of frequent consumption of foods that are high in sugar content, and the use of adhesive pit and fissure sealants. Personal use and professional provision of these methods in appropriate combinations can contribute significantly to future improvements in oral health. Meticulous personal oral hygiene practices combined with periodic professional care are the currently available means of protecting periodontal health. Through increased collaboration among various governmental, academic, and corporate entities, as well as active participation by individuals, the achievement of a number of these objectives becomes feasible to the benefit of national productivity, health care financing, and the quality of life for Americans.

Adolescent↗

PubMedDate not supplied

Pathogenesis of degenerative joint disease produced by in vivo freezing of rabbit articular cartilage.

In vivo freezing of rabbit lateral femoral arterial cartilage with a cryoprobe produces an osteoarthritic-like condition in 12 months. Previous studies have established that the chondrocytes are killed by the freezing process. A loss of stainable mucopolysaccharide occurs. The collagen content of the lesional tissue does not change. The present study investigates the extracellular lysosomal enzyme content, collagen type (I or II), and histologic changes which produce chondrocyte cell clusters in the frozen tissue in response to freezing or articular cartilage. The results indicate that after the initial 30 days there is no significant rise in the extracellular lysosomal enzyme content of the experimental tissue compared with controls. Type II, or cartilage, collagen remains the major constituent of the lesional tissue. Histologic examination at six- to 12-month intervals suggests that chondrocyte clones are produced by invasion by the underlying viable subchondral bone. These results provide insight into the pathogenesis of degenerative joint disease and the rationale of treatment by the use of inhibitors of vascular invasion of articular cartilage.

Animals↗