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R N Butler

Publications and source records attributed to R N Butler.

At least 37 records · Page 2Linked to original sources
PubMed2000

Anti-aging medicine. 2. Efficacy and safety of hormones and antioxidants.

Little is known about the efficacy and safety of substances that are being promoted to consumers as "anti-aging" therapies. Hormones such as DHEA, human growth hormone, and testosterone tend to decline with aging, but the therapeutic value of replacing them to "normal" physiologic levels has not been substantiated by controlled clinical trials. The best source of antioxidants is a balanced diet, although older patients may benefit from vitamin E supplementation. Providing anti-aging medicine in the primary care setting means practicing good medicine. It means talking to patients who request these therapies and understanding why they want them and how much risk they're willing to take.

Aging↗
PubMed1999

Factors affecting the validity of the 13C-urea breath test for in vivo determination of Helicobacter pylori infection status in a mouse model.

BACKGROUND: The mouse model using a human isolate of Helicobacter pylori is being widely accepted as an economical means of studying gastric infection. A noninvasive monitoring method would be useful for repeated testing to establish the time course of infection and the efficacy of treatments. In this study, we describe factors that affected interpretation of 13C urea breath test results for the assessment of H. pylori infection status in this model. MATERIALS AND METHODS: Female C57B1/6 mice that underwent gavage with H. pylori or saline were breath-tested using 50 micrograms of 13C urea at intervals up to 2 months after inoculation. The generation of 13CO2 (excess delta 13CO2) by infected mice was compared to that of uninfected controls. The effects of diet, fasting, and coprophagy on the reliability of the 13C urea breath test were quantitated. RESULTS: Both commercial and synthetic mouse diets exhibited marked in vitro urease activity. A minimum fasting time of 13 hours prior to breath testing significantly reduced this dietary contribution to excess delta 13CO2 values. The coprophagic tendency of the mice caused spuriously high excess delta 13CO2 counts in the breath of both control and H. pylori-infected mice. CONCLUSIONS: Although the dietary contribution to spuriously high values of excess delta 13CO2 in mice breath-tested for H. pylori infection was reduced by fasting, the high nonspecific urease activity generated by coprophagy severely limited the reliability of the urea breath test in the assessment of H. pylori infection status.

Animals↗
PubMed1999

Regional distribution and localization of zinc and metallothionein in the intestine of rats fed diets differing in zinc content.

BACKGROUND: Zinc (Zn) is protective and enhances epithelial repair in gut diseases. In this study we investigate the localization and distribution of Zn and its binding protein, metallothionein (MT), in the gut of rats fed diets varying in Zn content. METHODS: Male-Sprague Dawley rats were fed low, normal, high, or excess Zn in their diets (10, 100, 400, or 1000 mg Zn/kg, respectively) and killed 7 days later. Blood, liver, and gut tissues were collected. Tissue Zn was determined with atomic absorption spectrophotometery and MT with a Cd/haem affinity assay. Zn and MT were immunohistochemically localized in the small-intestinal wall with zinquin and an anti-MT antibody. RESULTS: Most Zn in the intestinal wall was present in the mucosal scrapings, with 94% membrane-bound and 6% cytosolic, irrespective of dietary Zn. MT levels increased in all gut regions at dietary Zn levels above 100 mg Zn/kg. MT was 40% higher in the ileum than in other gut regions in rats fed low- and normal-Zn diets. The Zn content of the ileum was also 20% higher than that of other gut regions in rats fed low-, normal-, or high-Zn diets. Zn and MT were colocalized in the base of the intestinal crypts, most visibly in the ileum. CONCLUSION: Mucosal cytosolic Zn and MT concentrations are increased only at high or excessive Zn intakes in all gut regions except the ileum, which can respond to a lower Zn intake. As the cytosolic Zn pool most likely influences mucosal protection and repair mechanisms, it is proposed that an increased MT may indicate the adequacy of oral Zn therapy in gut disease.

Abdominal Muscles↗
PubMed1999

Hypertension: setting new goals for lower readings.

Mean systolic blood pressures increase and mean diastolic pressures decrease with aging, primarily in response to the stiffening of blood vessels. These trends are related to the interplay of genetic factors that control renal, vascular, and hormonal functions. The prevalence of hypertension and the rate of blood pressure control vary among population groups; only one-fourth (24%) of all Americans with hypertension are controlled. Some persistent myths about hypertension may interfere with its diagnosis and treatment. Other barriers to control appear to be the side effects and cost of medications. Control rates improve when physicians increase their emphasis on patient education.

Aged↗
PubMed1999

Hypertension: therapeutic approach to weight loss, exercise, and salt intake.

Ideal body weight is difficult to achieve, but losing 10 lbs may be beneficial in controlling high blood pressure. Patients are more likely to exercise if they enjoy the activity, establish a routine, and exercise with a friend. Older Americans consume a lot of processed foods, the source of 80% of dietary salt. Most older African-Americans, especially those with obesity and type 2 diabetes, are salt-sensitive. Four steps to successful patient education are: 1) tell patients their blood pressure readings; 2) tell them about their medications and potential side effects; 3) provide culturally-sensitive printed materials; 4) use video tapes to educate all new patients and those with compliance problems.

Aged↗