Safety evaluation of an açai-fortified fruit and berry functional juice beverage (MonaVie Active(®)).

The safety of an açai (Euterpe oleracea Mart.) pulp enriched fruit and berry juice, MonaVie Active®, fortified with the functional ingredient, glucosamine, was studied. The beverage was found not to be mutagenic, clastogenic, cytotoxic, or genotoxic, as determined by the bacterial reverse mutation assay, chromosomal aberration assay, mouse micronucleus assay, and mammalian cell gene mutation (L5178Y) assay.

Toxicological evaluation of a dietary supplement formulated for male sexual health prior to market release.

The dietary supplement, 112 Degrees, was formulated with the goal of supporting sexual functioning in men. Due to rampant problems with drug adulteration for this category of products, a comprehensive screening for active pharmaceutical agents, with an emphasis on drugs prescribed for erectile dysfunction such as type 5 phosphodiesterase (PDE-5) inhibitors, and known unapproved PDE-5 drug analogues, was performed along with preclinical toxicology studies prior to the introduction of this product into the marketplace. 112 Degrees was found to be free of all pharmaceutical adulterants tested, and was not mutagenic, clastogenic, or genotoxic as demonstrated by the Ames test, chromosomal aberration assay, and mouse micronucleus assay, respectively.

Single- and repeated-dose oral toxicity studies of citicoline free-base (choline cytidine 5'-pyrophosphate) in Sprague-Dawley rats.

The dietary supplement Citicoline free-base (choline cytidine 5'-pyrophosphate) was toxicologically evaluated in Sprague-Dawley rats using oral gavage. In an acute 14-day study, 2000 mg/kg was well tolerated. In a 90-day study, 100, 350, and 1000 mg/kg/day doses resulted in no mortality.

Acute and subchronic toxicity studies of cryogenically-frozen, cryomilled, Pelodiscus sinensis (Japanese soft-shelled turtle--suppon) powder administered to the rat.

Sprague-Dawley rats received "cryogenically-frozen suppon" (CFS), a cryomilled product derived for the Japanese soft-shelled turtle (Pelodiscus sinensis), widely consumed for its nutritious value and medicinal properties, especially for the maintenance of normal blood pressure and insulin levels, and in women for the treatment of menopausal symptoms. In this acute study, a single limit dose of 2.0 g/kg was given po.

Toxicity of methylsulfonylmethane in rats.

Methylsulfonylmethane (MSM) is a popular dietary supplement used in a variety of conditions including pain, inflammation, allergies, arthritis, parasitic infections and the maintenance of normal keratin levels in hair, skin and nails. Despite its popularity, there is little published toxicology data on MSM. The objective of this study was to evaluate the acute and subchronic toxicity of MSM in rats at a dose five to seven times the maximum recommended dose in humans.

Cloning and characterization of gentamicin-resistance genes from Micromonospora purpurea and Micromonospora rosea.

Aminoglycoside-resistance genes (grm) were cloned from a gentamicin producer Micromonospora purpurea and a sisomicin producer Micromonospora rosea. The nucleotide (nt) sequences of both genes were determined and the similarity between them was very high (90.4% identity).

Down-regulation of c-myc and c-Ha-ras gene expression by tiazofurin in rat hepatoma cells.

There was an overexpression of the c-myc gene (11-fold) and of the c-Ha-ras gene (2-fold) in rat hepatoma 3924A cells compared to normal rat liver as measured by dot-blot analysis of total cytoplasmic RNA. The overexpression of c-myc was attributed to a 10- to 14-fold amplification and rearrangement of the c-myc sequences as determined by Southern blot analysis. The expression of the c-myc also was dependent upon the proliferative state of the hepatoma cells.

Characterization of the L1NH repeat family of Novikoff hepatoma.

Long interspersed repeated sequences of the Novikoff hepatoma rat tumour cell genome were cloned and studied. No basic differences were found when the genomic organization of the Novikoff hepatoma was compared with that of other mammalian L1 families. The nucleotide sequence of the central approximately 4 kb (1 kb = 10(3) bases) part of the Novikoff hepatoma LINE (L1NH) appeared to be more highly conserved than the sequences found at the 5' and 3' ends.

Characterization of the Cephalosporium acremonium ribosomal RNA genes.

To investigate the organization of the ribosomal RNA genes in Cephalosporium acremonium, we cloned the whole r X DNA repeat in pBR322 and pNEO plasmids. Both the cloned and the genomic r X DNA fragments were characterized by restriction mapping. The r X DNA repeat unit was found to be 8.

Supercoil induced S1 hypersensitive sites in the rat and human ribosomal RNA genes.

Rat and human ribosomal RNA gene fragments in supercoiled plasmids were examined for S1 nuclease hypersensitivity. In the transcribed portion of genes the number and distribution of S1 sites were found to be species specific. No S1 sites were detected in the promoter regions.

Cloning and characterization of a Novikoff hepatoma ribosomal DNA-fragment containing the initiation site of transcription.

A 10.3 kilobase EcoRI fragment of Novikoff hepatoma rat ascites tumor ribosomal gene was cloned in pBR322 vector. The cloned fragment contained part of the 18S RNA gene, and about 8 kilobases of the 5' spacer region.

Interaction of GGCC sequences of DNA with anticancer dianhydrogalacticol, detected by inhibition of restriction enzyme BspI.

Interaction of DNA with 1,2-5,6-dianhydro-galactitol (DAG, NSC 132 313), a bifunctional alkylating agent used in cancer therapy was studied. Treatment of lambda phage DNA with DAG in vitro protected some of the specific cleavage sites against the restriction enzyme BspI. The extent of protection depended on the concentration and time of DAG treatment but complete protection was not observed.

Fractionation and reconstitution of factors required for accurate transcription of mammalian ribosomal RNA genes: identification of a species-dependent initiation factor.

Mouse and human cell extracts (S100) can support an accurate and efficient transcription initiation on homologous ribosomal RNA gene (rDNA) templates. The cell extracts were fractionated with the aid of a phosphocellulose column into four fractions (termed A, B, C and D), including one containing a major part of the RNA polymerase I activity. Various reconstitution experiments indicate that fraction D is an absolute requirement for the correct and efficient transcription initiation by RNA polymerase I on both mouse and human genes.

Human ribosomal RNA gene: nucleotide sequence of the transcription initiation region and comparison of three mammalian genes.

The transcription initiation site of the human ribosomal RNA gene (rDNA) was located by using the single-strand specific nuclease protection method and by determining the first nucleotide of the in vitro capped 45S preribosomal RNA. The sequence of 1,211 nucleotides surrounding the initiation site was determined. The sequenced region was found to consist of 75% G and C and to contain a number of short direct and inverted repeats and palindromes.

Nucleotide sequence of the transcription initiation region of a rat ribosomal RNA gene.

We cloned the part of the rDNA containing the transcription initiation region, and determined the exact site of initiation of the 45S RNA transcription. The nucleotide sequence of the region surround the initiation site was determined. Comparison of the mouse and rat genes revealed extensive homology between the initiation regions of the two species.

Phenotypic correction of nonsense mutation carrying non-converting PE5 phages in Shigella flexneri with suppressor gene.

(i) Phenotypic suppression by aminoglycoside antibiotics of a polyauxotrophic Shigella flexneri var. Y strain on partially completed minimal medium has shown that its Thr dependence is associated with nonsense mutation. Induced Thr+ revertants selected from the culture yielded clones correcting the lytic cycle of nonsense T4 mutant phages.

Phage-dependent changes in Shigella flexneri type antigen synthesis.

Lysogenic conversion of Shigella flexneri type antigens was studied with the aid of wild-type and thermosensitive mutant phages. With all wild-type phages, the appearance of glycosylated antigen was accompanied by the appearance of polyprenyl phosphate glucose synthetase activity. With some of the mutant phages, the appearance of glycosylated antigen was not followed by the formation of lipid-linked glucose in the enzyme assay.

Generalized transduction Of shigella flexneri by converting phage PE5.

Phage PE5, responsible for the conversion of type V antigen in Shigella flexneri, has the ability to produce generalized transduction. The correlation between phage multiplicity and the number of transductants, the specific inhibitory activity of anti-PE5 serum, and the lack of transduction in PE5 resistant recipients, indicate the role of phage PE5 in generalized transduction. Transduction of the R100-1 factor resulted in a non-transmissible tetracycline resistance segragation.