Change in mutagenicity in white rice after accelerated and long-term storage

Certain reactions that occur in food during storage, such as nonenzymatic browning and lipid oxidation, form compounds that have been shown to be mutagenic. It is possible that over long storage periods, significant amounts of these products could be formed. Although some research has been published concerning the mutagenicity of foods due to processing or cooking, little research has been done regarding mutagenicity of foods stored for an extended time. The objective of this research was to determine the potential mutagenicity of white rice held in accelerated and long-term storage using the Ames Salmonella/microsome assay. Fresh long-grain white rice was packaged in foil laminate pouches and held at 60 degrees C for 18 wk. Rice stored for > 25 y in an oxygen-free environment at or below room temperature in size number 10 cans was obtained from residential storage. The standard plate-incorporation method was used to evaluate the mutagenic potential of all treatments using Salmonella typhimurium tester strains TA97a, TA98, TA100, and TA102. Samples were plated at 5 dilutions with and without rat liver S9 enzyme. A solvent control was also plated for each strain. Treatments yielding counts at least double the solvent control level were considered mutagenic. Plate counts for all treatments fell well below the required doubling of the solvent control value. White rice held in accelerated and long-term storage appears not to increase in mutagenic compounds as measured by the Ames assay, supporting its use for long-term storage purposes such as emergency preparedness and humanitarian food aid.

Lower calorie intake enhances muscle insulin action and reduces hexosamine levels

Previous studies have demonstrated enhanced insulin sensitivity in calorie-restricted [CR, fed 60% ad libitum (AL) one time daily] compared with AL-fed rats. To evaluate the effects of reduced food intake, independent of temporal differences in consumption, we studied AL (unlimited food access)-fed and CR (fed one time daily) rats along with groups temporally matched for feeding [fed 3 meals (M) daily]: MAL and MCR, eating 100 and 60% of AL intake, respectively. Insulin-stimulated glucose transport by isolated muscle was increased in MCR and CR vs. AL and MAL; there was no significant difference for MCR vs. CR or MAL vs. AL. Intramuscular triglyceride concentration, which is inversely related to insulin sensitivity in some conditions, did not differ among groups. Muscle concentration of UDP-N-acetylhexosamines [end products of the hexosamine biosynthetic pathway (HBP)] was lower in MCR vs. MAL despite unaltered glutamine-fructose-6-phosphate aminotransferase activity (rate-limiting enzyme for HBP). These results indicate that the CR-induced increase in insulin-stimulated glucose transport in muscle is attributable to an altered amount, not timing, of food intake and is independent of lower triglyceride concentration. They further suggest that enhanced insulin action might involve changes in HBP.

Conversion of dietary phylloquinone to tissue menaquinone-4 in rats is not dependent on gut bacteria

The ability of male rats to accumulate menaquinone-4 (MK-4) in tissues when fed a vitamin K-deficient diet supplemented with intraperitoneal phylloquinone (K) as the sole source of vitamin K for 14 d was assessed. In both conventionally housed controls and gnotobiotic rats, supplementation with the equivalent of 1500 microg vitamin K/kg diet increased (P < 0.001) tissue MK-4 concentrations above those of controls fed a vitamin K-deficient diet. MK-4 concentrations were approximately 5 ng/g (11 pmol/g) in liver, 14 ng/g in heart, 17 ng/g in kidney, 50 ng/g in brain and 250 ng/g in mandibular salivary glands of gnotobiotic rats. MK-4 concentrations in conventionally housed rats were higher than in gnotobiotic rats in heart (P < 0.01), brain (P < 0.01) and kidney (P < 0.05) but lower in salivary gland (P < 0.05). Cultures of a kidney-derived cell line (293) converted K to the expoxide of MK-4 in a manner that was dependent on both time of incubation and concentration of vitamin K in the media. A liver-derived cell line (H-35) was less active in carrying out this conversion. These data offer conclusive proof that the tissue-specific formation of MK-4 from K is a metabolic transformation that does not require bacterial transformation to menadione as an intermediate in the process.

Homeopathic treatment of depression and anxiety

BACKGROUND

Homeopathy is a well-established therapeutic system with potential relevance to psychiatry, but as yet it is largely untested.

OBJECTIVE

To report the use of homeopathic treatment in patients with depression and anxiety.

METHODS

Individually selected homeopathic remedies were used on an outpatient basis to treat 12 adults who had major depression, social phobia, or panic disorder. The patients either requested homeopathic treatment or received it on a physician's recommendation after partial or poor response to conventional therapies. Duration of treatment was 7 to 80 weeks. Response was monitored by using a clinical global scale (n = 12), the self-rated SCL-90 scale (n = 8), and the Brief Social Phobia Scale (n = 4).

RESULTS

Overall response rates were 58% according to the clinical global improvement scale and 50% according to the SCL-90 or the Brief Social Phobia Scale.

CONCLUSIONS

Homeopathy may be useful in the treatment of affective and anxiety disorders in patients with mildly to severely symptomatic conditions.

Red blood cell catechol O-methyl transferase and response to imipramine in unipolar depressive women

When baseline red blood cell catechol O-methyltransferase (COMT) was measured in 15 unipolar depressive women, the authors found a linear correlation between COMT and response to imipramine (best outcome occurring at low COMT). The results of this study were not related to such variables as intensity of depression, family history, or psychiatric history. The authors suggest that this assay may be useful either as a predictor of response to the drug or as a guide in choosing the optimum dose.

The nevoid basal cell carcinoma syndrome

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Holt-Oram syndrome: clinical and genetic study of a large family

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