Ginseng supplementation does not enhance healthy young adults' peak aerobic exercise performance.

OBJECTIVE: To determine the short term effects (21 days) of 200 mg (7% standardized) Panax ginseng supplementation vs. placebo on peak aerobic exercise performance in healthy young adults, with unrestricted diets. METHODS: Twenty men and eight women (age = 23.2 +/- 3.2 years, height = 175.8 +/- 8.6 cm; weight = 75.2 +/- 15.3 kg) were randomly assigned to either a Panax ginseng or placebo group for a period of 3 weeks in a double blind design. Prior to and following treatment the subjects performed a symptom limited graded exercise test on a Schwinn Airdyne ergometer. The data were analyzed using an analysis of variance. RESULTS: No significant treatment effect was observed for the dependent variables of VO2, exercise time, workload, plasma lactate and hematocrit at peak levels, or for heart rate and rate of perceived exertion at 150 watts, 200 watts and peak. CONCLUSIONS: The results of this study do not support an ergogenic effect on peak aerobic exercise performance following a 3-week supplementation period of 200 mg 7% Panax ginseng in healthy young adults with moderate exercise capacities and unrestricted diets.

Suppression of growth by dietary fish oil of human breast carcinomas maintained in three different strains of immune-deficient mice.

It has been reported that high levels of dietary fish (menhaden) oil, compared with corn oil, suppress the growth of MDA-MB231 and MCF-7 human breast carcinomas maintained in female athymic nude (T lymphocyte-deficient) mice. The purpose of this study was to determine whether dietary fish (menhaden) oil, compared with corn oil, can also suppress the growth of these carcinomas when maintained in female beige-XID-athymic nude (T lymphocyte- and NK/LAK cell-deficient) mice and in female severe combined immune-deficient (SCID) mice (total lack of functional T and B lymphocytes). Results clearly show that dietary fish (menhaden) oil can significantly (p < 0.05) suppress the growth of these carcinomas in the beige-XID-athymic nude mouse and the SCID mouse. Such results provide evidence that the growth suppression of MDA-MB231 and MCF-7 human breast carcinomas, induced by dietary fish oil, is not mediated by immune system mechanisms involving T lymphocytes, B lymphocytes, and/or NK/LAK cells.

A mouse model of focal cerebral ischemia for screening neuroprotective drug effects.

The aim of the present study was to investigate if the infarct area on the brain surface after middle cerebral artery (MCA) occlusion in the mouse is representative for the infarct volume and if this determination of brain injury can be used for screening neuroprotective drug effects. Cerebral infarction was induced by coagulating electrically the stem of the left MCA. After 48 hr, the brains were perfused with carbon black and the unstained infarct area was determined by means of an image analyzing system. The infarct volume was determined by calculating the infarct area on coronal slices and the distance between succeeding slices. The correlation between the area and the volume of infarction was significant (r = 0.81; p less than 0.001). N-methyl-D-aspartate (NMDA) antagonists, calcium antagonists, 5-hydroxytryptamine-1A (5-HT-1A) agonists, radical scavengers, and various drugs were investigated in the mouse model of MCA occlusion. Drugs were usually applicated before ischemia. The drugs that were found to be neuroprotective in the mouse model revealed similar effects in rat models of focal or global cerebral ischemia. These findings show that the presented mouse model with its simple technique of measuring the infarct size is suitable for screening purposes.

Neuroprotective effect of nimodipine is not mediated by increased cerebral blood flow after transient forebrain ischemia in rats.

In the present study, we investigated the protective effect of nimodipine against postischemic neuronal damage in the rat and considered the question of whether this histologic finding coincides with an improvement of cerebral circulation. Male Wistar rats were subjected to 10 minutes of forebrain ischemia by clamping both common carotid arteries and lowering blood pressure to 40 mm Hg. Histologic evaluation was performed 7 days after ischemia. Local cerebral blood flow was determined with the 14C-iodoantipyrine technique in anatomically defined areas of the brain, including hippocampus. Preischemic application of nimodipine (3.0 mg/kg p.o.) significantly reduced the percentage of damaged neurons in hippocampal CA1 subfield from 78 +/- 4% in controls to 59 +/- 6% in treated rats (mean +/- SEM; p less than 0.05, Mann-Whitney U test). After 10, 60, and 180 minutes of recirculation no differences in local cerebral blood flow between control and drug-treated animals were observed. Our results demonstrate that nimodipine reduces ischemia-induced neuronal damage in rat hippocampus. We did not consider increased cerebral blood flow in the hypoperfusion state in the applied experimental design since improvement of cerebral blood flow seems to bear little relation to the neuroprotective activity of nimodipine.

[Iatrogenic fluorosis. 2 cases]. / Fluorose iatrogène. Deux observations.

Two new cases of osteofluorosis are presented. They are attested by the existence of a bone X-ray densification, by histological lesions of hyperosteoidosis and a large increase in the fluorine content. One is a 61 year-old man who consumed 2.5 l a day of Vichy St-Yorre (a mineral water containing 8 mg of fluorine ions per litre) during 11 years; the other, an 86 year-old man who during 20 years took 500 mg of niflumic acid a day, a non-steroidal anti-inflammatory drug containing 3 fluorine atoms per molecule (i.e., 50 mg fluorine per 250 mg gellule). Both these hypertensive patients had severe renal insufficiency. These two observations serve as a reminder of the indispensable precautions to be observed when prescribing fluorine salts in the treatment of post-menopausal osteoporosis: at least the plasma creatinine level should be available in order to calculate the endogenous creatinine clearance and any possible supplementary intake of fluorine salts should be checked.

Reduction of postoperative donor blood requirement by use of the cell separator.

In a prospective, randomized study of 20 patients undergoing elective open-heart surgery, up to c. one-third of the total intraoperative and postoperative transfusion requirement could be provided by autologous centrifuged blood. Retransfusion of washed, packed red blood cells freed from cellular debris, heparin and activated clotting factors significantly reduced blood loss during and after surgery. The cell separator is a valuable aid in autotransfusion technique.