Distribution and toxicity of mercury in rats after oral administration of mercury-contaminated whale red meat marketed for human consumption.

Toothed-whales and dolphins have been hunted for human consumption in Japan, and their muscles (red meats) are highly contaminated with mercury (Hg). We investigated the distribution and toxicity of Hg in rats after oral administration of Hg-contaminated whale red meat marketed for human consumption in Japan. Rats were orally administered the red meat homogenate for seven consecutive days (0.5 g red meat/kg-bw/day). The red meat administered to rats contained 81microg/g of total mercury (T-Hg) and 13.4 microg/g of methyl mercury (M-Hg). This dose corresponds to the human consumption of 210 g red meat/60 kg-bw/week, exceeding by about 29 times the provisional tolerable weekly intake of M-Hg at 1.6 microg/kg-bw/week set by JECFA [JECFA, 2003. Joint FAO/WHO expert committee on food additives. 61st meeting, Rome]. Twenty-four hours after the last administration, the distribution of T-Hg in rat organs and biochemical parameters in serum were analyzed. The administration of red meat significantly elevated T-Hg concentrations in the liver, kidney, erythrocytes, cerebral cortex and medulla oblongata from the control levels but did not elevate the T-Hg concentration in serum, showing the typical distribution pattern of M-Hg, not of inorganic Hg. The administration slightly but significantly increased GTP activity and P concentration and decreased BUN concentration in serum, although no abnormalities were observed in rat body weight gain and movement during the 7 days. The occasional consumption of red meat from small cetaceans, therefore, could pose a health problem for not only pregnant women but also for the general population.

[Effects of bofu-tsusho-san, a traditional Chinese medicine, on body fat accumulation in fructose-loaded rats].

The effects of Bofu-tsusho-san (BOF), a traditional Chinese medicine, on fructose-induced hypertriglyceridemia and body fat accumulation were investigated in female SD rats. Rats were allowed to drink ad libitum 25% (w/w) fructose solution for 6 weeks. BOF was administered to the rats as an experimental diet containing 1.5% or 4.5% (w/w) of BOF during the fructose-loading period. BOF suppressed body weight gain and prevented the elevation of serum triglyceride levels and body fat accumulation in fructose-loaded rats without affecting food and fructose intake. Furthermore, BOF prevented the increase of triglyceride content in the liver and the reduction of mitochondrial cytochome c oxidase activity in the brown adipose tissue induced by fructose. From these results, it has been suggested that BOF has a preventive effect against the body fat accumulation caused by excess intake of sugar or other fructose-containing foods. The inhibition of triglyceride synthesis in the liver, and the enhancement of lipolysis in adipocytes and of thermogenesis in brown adipose tissue have been presumed as the mechanisms of action of BOF.

[Predonation and transfusion in open heart surgery].

The efficacy of predonation of autologous blood in reducing the use homologous blood during open heart surgery was investigated. Between January 1997, and February 1998, predonation and transfusion was studied in 100 consecutive open heart operations (CABG, 77; valve surgery, 17; ASD, 5; myxoma, 1). The guidelines for autologous predonation were as follows: an age < 70 years, a weight > 40 kg and a hemoglobin > 12 g/dl. Patients in NYHA class IV or undergoing emergency operation were excluded. The blood loss during operation ranged from 195 to 1,850 ml (mean; 670 ml), being from 305 to 1,850 ml (723 ml) for CABG, from 260 to 1,020 ml (493.5 ml) for valve surgery and from 195 to 570 ml (342 ml) for ASD. The blood loss was not significantly dependent on sex or age and did not differ elective and emergent operations. Only 36.6% of patients with autologous predonation needed homologous transfusion versus 63.4% of those without predonation. Homologous transfusion was done in only 5% of the those with predonation of 800 ml versus 69% at 400 ml and 71% at 200 ml. In conclusion, autologous blood transfusion is effective for reducing the homologous blood requirement. It also seems that predonation of 800 ml may be sufficient to allow open heart surgery without blood transfusion.

[Surgical treatment of aortic dissection (Stanford type A) using hypothermic retrograde cerebral perfusion in patients older than 70 years of age].

Since 1991, 27 consecutive patients with aortic dissection (Stanford A) have been operated on using deep hypothermic retrograde cerebral perfusion (RCP). There were no differences in ECC time (247 +/- 15 vs 307 +/- 22 min), and RCP time (47 +/- 2 vs 47 +/- 3 min) between the aged (> or = 70 y.o., n = 11) and non-aged (< 70 y.o., n = 16) group. Although the aged group showed the higher incidences of postoperative neurological complications of prolonged emergence (2 cases) and delirium (3 cases), respiratory disorder (3 cases), and renal dysfunction (3 cases), there was no significant difference in hospital mortality (18% in the aged vs 13% in the non-aged). We concluded that RCP is well acceptable procedure for surgical treatment of the aged patients with aortic dissection.

Intraventricular administration of estradiol modulates rat prolactin secretion and synthesis.

The effect of estradiol (E2) on rat tuberoinfundibular dopaminergic (TIDA) neurons was examined in vivo, employing chronic intraventricular (i.c.v.) infusion technique using an osmotic mini-pump. The activity of TIDA neurons was assessed by the release and synthesis of prolactin (PRL) in the rat pituitary gland and by the changes in the 3, 4-dihydroxyphenylacetic acid (DOPAC) and dopamine (DA) levels and in the DOPAC/DA ratio in the rat hypothalamus. We also examined the [3H] E2 binding in the rat hypothalamus. Ovariectomized female Wistar rats with E2 replacement were treated with daily i.c.v. infusion of 1 microM of E2 or saline vehicle for 1, 3, and 7 days using the Alzet osmotic mini-pump and brain infusion kit. At 1 day of i.c.v. infusion of E2, the serum PRL level was significantly decreased compared with that in the vehicle group. Northern blot analysis of the total RNA isolated from the pituitary glands demonstrated a decrease in the PRL gene transcript level in the E2 group. At 3 days of E2 treatment, however, the serum PRL level was significantly increased compared with that of the vehicle-injected group and Northern blot analysis also demonstrated that the PRL gene transcript level was increased in the E2 group. At 7 days of E2 administration, there were no significant differences between the E2 and vehicle groups in either serum PRL or PRL gene transcript levels. There was a significant increase in the DOPAC/DA ratio after 1 day in the E2 group. However, no significant effects of E2 on this ratio were observed at 3 and 7 days of treatment. The DOPAC concentration in the E2 group was significantly increased at day 1 and significantly decreased at day 3, compared with that of the respective time in vehicle group. At day 7 there was no significant change in DOPAC concentration in either groups. The DA concentrations in the hypothalamus was not changed on any day in either group. Specific [3H] E2 binding was observed in the rat hypothalamus. These data suggest that E2 may have a biphasic effect on the accumulation of PRL gene transcripts and on the PRL secretion in the rat pituitary by first stimulating and then inhibiting the TIDA neuronal activity.

[Studies on the constituents of edible and medicinal plants. IV. Determination of 4-O-methylpyridoxine in serum of the patient with gin-nan food poisoning].

The serum 4-O-methylpyridoxine (MPN) levels in a 21 months-old patient with gin-nan food poisoning were determined by HPLC. The blood of the patient was taken at 8.5 and 15.5 h after taking about 50 ginkgo albumens. After deproteinization of the serum, the supernatant was pretreated with Sep-pak C18 cartridge and was applied to HPLC. HPLC was performed with a Hibar LiChrosorb RP-18 (4.0 mm i.d. x 250 mm, 7 microns) using a fluorescence detector (wave length of excitation and fluorescence; 290 and 400 nm, respectively). The serum MPN level was determined by the absolute calibration method. The determination limit of MPN in the serum was 0.05 micrograms/ml. The serum MPN concentration was 0.09 micrograms/ml at 8.5 h after taking ginkgo seeds, and was less than the determination limit of MPN (0.05 micrograms/ml) at 15.5 h. MPN, isolated from the seed of Ginkgo biloba L., is responsible for "gin-nan food poisoning," and its cardinal symptoms are mainly tonic and/or clonic convulsions and loss of consciousness. Infants are particularly vulnerable. This method may be available for proving the gin-nan food poisoning, chemically.

A new method for evaluating mucolytic expectorant activity and its application. I. Methodology.

A new method for evaluating in vivo effect of mucolytic expectorants was devised. In this report, however, the focus is placed on methodology but not on pharmacology. Rabbits with subacute bronchitis were prepared by long-term exposure to minute amounts of SO2 gas. The sputum was quantitatively collected from the animal through a tracheal cannula at suitable time intervals according to the Perry and Boyd's method. As a preliminary study, changes in volume, viscosity and amounts of freeze-dried substance of sputa were examined after intraduodenal administration of water instead of mucolytic expectorants, the effects of which will be described in the subsequent paper, but no significant changes occurred with this test.

Seasonal variation of saponins, sucurose and monosaccharides in cultivated ginseng roots.

Yield of methanolic extract of fresh roots of Ginseng harvested in winter was found to be more than two-fold grater than from roots collected in summer; this remarkable increase is mainly due to the large increase of sucrose in roots in winter. On the other hand, biologically active dammarane-saponins in the roots increase in summer. These results indicate that roots should be harvested in summer for the production of high quality Ginseng extracts.