Mercury and selenium concentrations in lanugo of free-ranging California sea lions in the southern Gulf of California, Mexico.

Total mercury ([THg]) and selenium ([TSe]) concentrations were determined in California sea lion (Zalophus californianus) lanugo from the Gulf of California in 2021 and 2022. Relationships with sex, morphometrics, and year were evaluated. Following toxicological thresholds of concern for piscivorous mammals, most pups had a [THg] < 10 ppm, one pup (2021) had a [THg] > 20 ppm, no pups had a [THg] > 30 ppm. Females had significantly higher [TSe] than males; sex did not influence [THg]. [THg] and [TSe] in 2022 were significantly higher in the general population and male cohorts compared to 2021. Significant negative correlations were observed between [THg], [TSe], and morphometrics (2021). These results indicate that, compared to other pinniped species, regional California sea lions may have a decreased likelihood of experiencing Hg-related adverse health effects. Year-related changes in element concentrations suggest continued monitoring of this population to assess pinniped, environmental, and potentially, human health.

Maintenance on a ketogenic diet: voluntary exercise, adiposity and neuroendocrine effects.

BACKGROUND: Adherence to low-carbohydrate, ketogenic diets (KDs) has been associated with greater weight loss in the short-term than low-fat, calorie-restricted diets. However, consumption of KDs may result in decreased voluntary exercise and thus render long-term weight loss and maintenance of weight loss difficult. METHODS: Rats were maintained on either a non-ketogenic chow (CH) diet or a low-carbohydrate, KD for 6 weeks. Half of each dietary group was sedentary, whereas the other half was given access to a running wheel. Running wheel activity (total distance and meters per minute), plasma leptin and insulin, adiposity, and hypothalamic mRNA for neuropeptide Y and proopiomelanocortin (POMC) were measured to assess activity-related effects in animals maintained on KD. RESULTS: With access to a running wheel, rats on KD engaged in similar levels of voluntary activity as CH rats and both dietary groups decreased caloric intake. Caloric intake increased over time such that it was significantly greater than sedentary controls after 1 month of access to the wheels, however body weight remained decreased. Sedentary rats maintained on KD had increased adiposity and plasma leptin levels and decreased hypothalamic POMC mRNA, as compared to sedentary CH rats. KD rats with access to a running wheel had similar levels of adiposity and plasma leptin levels as CH rats with access to running wheels, but significantly increased POMC mRNA in the arcuate. CONCLUSION: We demonstrate that maintenance on KD does not inhibit voluntary activity in a running wheel. Furthermore, prevention of KD-related increased adiposity and plasma leptin, as measured in sedentary KD rats, significantly increases levels of the anorexigenic neuropeptide POMC mRNA.

Short-term safety evaluation of processed calcium montmorillonite clay (NovaSil) in humans.

NovaSil clay (NS) provides significant protection from the adverse effects of aflatoxins (AFs) in multiple animal species by decreasing bioavailability from the gastrointestinal tract. It is postulated that NS clay can be safely added to human diets to diminish exposure and health risks from AF contaminated food. To determine the safety and tolerance of NS in humans and establish dosimetry protocols for long-term efficacy studies, a randomized and double-blinded phase I clinical trial was conducted. Volunteers (20-45 yr in age), were clinically screened for confirmation of their health status. Fifty subjects (23 males and 27 females) were randomly divided into two groups: The low-dose group received nine capsules containing 1.5 g/day, and the high-dose group received nine capsules containing 3.0 g/day for a period of 2?wk. NS capsules were manufactured in the same color and size and were distributed to each participant three times a day at designated sites where follow-up was taken to record any side effects and complaints. Blood and urine samples were collected before and after the study for laboratory analysis. All participants completed the trial and compliance was 99.1%. Mild GI effects were reported in some participants. Symptoms included abdominal pain (6%, 3/50), bloating (4%, 2/50), constipation (2%, 1/50), diarrhea (2%, 1/50), and flatulence (8%, 4/50). No statistical significance was found between the two groups for these adverse effects (p > 0.25). No significant differences were shown in hematology, liver and kidney function, electrolytes, vitamins A and E, and minerals in either group. These results demonstrate the relative safety of NS clay in human subjects and will serve as a basis for long-term human trials in populations at high risk for aflatoxicosis.

The effect of folic acid supplementation on plasma homocysteine in an elderly population.

BACKGROUND: Increased plasma homocysteine is associated with coronary artery disease, peripheral vascular disease and venous thrombosis. Folic acid is the most effective therapy for reducing homocysteine levels. The lowest effective supplement of folic acid is not known, particularly for the elderly who have the highest prevalence of these conditions. AIM: To explore the effects of daily supplements of 0, 50, 100, 200, 400 and 600 microg folic acid on plasma homocysteine in an elderly population. DESIGN: Randomized double-blind placebo-controlled trial. METHODS: Participants (n=368) aged 65-75 years were randomly allocated to receive one of the treatments for 6 weeks. Plasma homocysteine was recorded after 3 weeks and 6 weeks of supplementation. RESULTS: Only the 400 microg and 600 microg groups had significantly lower homocysteine levels compared to placebo (p=0.038 and p<0.001, respectively). Using multiple linear regression and each individual's total folic acid intake (diet plus supplement), a total daily folic acid intake of 926 microg per day would be required to ensure that 95% of the elderly population would be without cardiovascular risk from folate deficiency. DISCUSSION: A daily folic acid intake of 926 microg is unlikely to be achieved by diet alone. Individual supplementation or fortification of food with folic acid will be required to reach this target.

Cervical screening by socio-economic status in Australia.

OBJECTIVES: To examine differentials and time trends in self-reported Pap test rates by socio-economic status (SES) from the 1989/90 and 1995 Australian National Health Surveys (NHS). METHODS: The unit record data for females were extracted from the two NHSs and combined. The outcome variable of interest was 'having a Pap test in the past three years'. The principal study factor was SES measured as individual characteristics and SES of area of residence. Migrant status, rurality, year of survey and age were controlled for in logistic regression models. RESULTS: Self-reported rates of having a Pap test in the past three years were higher in women from higher compared with lower SES groups. Compared with women with a bachelor or higher degree, the odds of reporting having a Pap test in the past three years in women with no post-school qualification was 0.86 (p<0.0005). Women with a gross annual income of less than $20,000 had significantly lower odds (OR=0.79) compared with women earning $40,000 or more. Blue collar (OR=0.84) and not employed (OR=0.73) women also had significantly lower odds compared to the referent white collar group. CONCLUSION: This study reveals differentials in Pap screening behaviour by individual measures of SES in Australia. Area-based SES measures under-estimated the SES differentials in Pap test rates compared with individual measures. Derived population attributable fractions reveal that about a quarter of self-reported under-screening is accounted for by low SES when measured individually, compared to 8% when SES is measured ecologically.

Preoperative hyperbaric oxygen therapy for radiation induced injuries.

PURPOSE: We present our experience with preoperatively administered hyperbaric oxygen therapy to patients who have sustained significant therapeutic radiation induced soft tissue injuries and subsequently undergo planned abdominal intervention/surgery. MATERIALS AND METHODS: From February 1993 to May 1997, 5 patients with a history of complications following therapeutic radiation were prospectively treated with hyperbaric oxygen before a planned abdominal operation. RESULTS: All patients had uneventful hospital courses. An additional procedure was eventually necessary in 2 patients but with fewer radiation related problems following hyperbaric oxygenation. CONCLUSIONS: Hyperbaric oxygenation may improve postoperative outcomes when given before planned open operations in patients with previous therapeutic pelvic irradiation and a history of radiation related complications.

Medicine--a healing or a dying art?

That medicine is a science is the popular belief, and this has been reinforced by the advent of 'evidence-based medicine', which assumes that scientific proof is required to support medical practice. However, the view of science implied is a narrow one, foreign both to pure scientists and to artists, and the art of medicine is devalued by the approach. There are both important differences and important similarities between science and the arts. The arts should contribute to evidence-based practice and education along with science, and have a role in many aspects of medical practice.

The safety of nitrendipine in the treatment of essential hypertension--a review of 61 clinical studies.

To assess the safety of the calcium channel blocker nitrendipine, data from 61 clinical studies conducted in the United States and involving 1,245 patients were reviewed. The drug appeared to be tolerated in the majority of patients and the dropout rate was low. The most common side effects associated with nitrendipine administration were headache and edema. Most side effects were mild and were tolerated or disappeared with continued therapy. No serious adverse biochemical, hemodynamic, renal, or humoral effects of nitrendipine were apparent. Nitrendipine produced a prompt, smooth, and sustained reduction in systolic and diastolic blood pressures in both the supine and standing positions. The blood pressure response was maintained for six months to one year with no evidence of resistance or tachyphylaxis. Sex and race had no influence on the antihypertensive effect of nitrendipine, but patients sixty years of age and older appeared to respond better to the drug than younger patients.

Lability of blocking antibody during ragweed immunotherapy.

The long-term immunologic changes with allergy injection therapy have been widely studied. There are few data, however, on the immunologic response to a single injection during the course of this therapy. Ten patients who had attained maintenance (1:100 w/v) within six months and 13 patients who had been on maintenance longer than three years were compared. Following baseline studies patients received their standard ragweed injections and were followed without further injections for 30 days. Titrated prick tests to short ragweed, specific IgE to short ragweed and IgG antibody to ragweed AgE were determined at intervals during the 30 days. Baseline values of skin tests, specific IgE and specific IgG did not differ significantly for the two groups. Values for all three parameters did not fluctuate significantly during the study. This study suggests that blocking antibody levels are stable soon after reaching maintenance and that allergy injections can be safely administered at monthly intervals beginning at that time.