The delaying effect of alpha-glycerophosphocholine on senescence,transthyretin deposition,and osteoarthritis in senescence-accelerated mouse prone 8 mice

Abstract

Administration of alpha-glycerophosphocholine (GPC), a choline compound in food, is expected to contribute to human health. In this study, we evaluated its effect on aging in senescence-accelerated mouse prone 8 (SAMP8) mice. Male SAMP8 mice had free access to a commercial stock diet and drinking water with or without GPC (0.07 mg/ml). Mice in the GPC group had significantly lower total senescence grading score than that of the control group at 36 weeks of age. Administration of GPC decreased the deposition of transthyretin (TTR), an amyloidogenic protein, in the brain. Aggregated TTR activated microglia and led to neuroinflammation. Thus, GPC would protect the brain by reducing TTR deposition and preventing neuroinflammation. In a histological study of knee joints, it was found that SAMP8 mice administered GPC showed decreased joint degeneration. These results suggest that GPC delays the aging process and may be a useful compound in anti-aging functional food development.     

The assembly of montane biotas: linking Andean tectonics and climatic oscillations to independent regimes of diversification in Pionus parrots

The mechanisms underlying the taxonomic assembly of montane biotas are still poorly understood. Most hypotheses have assumed that the diversification of montane biotas is loosely coupled to Earth history and have emphasized instead the importance of multiple long-distance dispersal events and biotic interactions, particularly competition, for structuring the taxonomic composition and distribution of montane biotic elements. Here we use phylogenetic and biogeographic analyses of species in the parrot genus Pionus to demonstrate that standing diversity within montane lineages is directly attributable to events of Earth history. Phylogenetic relationships confirm three independent biogeographic disjunctions between montane lineages, on one hand, and lowland dry-forest/wet-forest lineages on the other. Temporal estimates of lineage diversification are consistent with the interpretation that the three lineages were transported passively to high elevations by mountain building, and that subsequent diversification within the Andes was driven primarily by Pleistocene climatic oscillations and their large-scale effects on habitat change. These results support a mechanistic link between diversification and Earth history and have general implications for explaining high altitudinal disjuncts and the origin of montane biotas.     

Intrahepatic territory of the accessory hepatic artery in the human

The accessory hepatic artery was found in 12 human livers and its intrahepatic territory was investigated. The artery supplies an entire lobe or more without joining the usual hepatic artery in 93% of the cases. The accessory hepatic artery has an important significance for the arterial supply of the liver.     

Misincorporation in DNA synthesis after modification of template or polymerase by MNNG, MMS and UV radiation

The synthetic DNA polymers, poly(dG-dC), poly(dC), poly(dA-dT), poly(dA) and poly(dT), were treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), methyl methanesulfonate (MMS) and UV irradiation. The modified polymers were used as templates to examine the incorporation of non-complementary nucleotides by E. coli DNA polymerase I. Methylation of poly(dG-dC) by MNNG predominantly induced the misincorporation of dTMP, whereas methylation by MMS induced that of dAMP. Treatment of poly(dT) with MNNG caused the misincorporation of dGMP to a considerable extent, but MMS did not enhance the error on poly(dT). The misincorporation of dAMP on poly(dC) and that of dGMP on poly(dA) were also increased by these chemicals. UV irradiation of poly(dT) and poly(dC) induced the error of dGMP and dAMP, respectively. These data on MNNG and MMS in vitro were in fair agreement with the directions of mutation in vivo. But the predominant induction of transitions by UV in vitro did not agree with the UV-induced transversions in E. coli. This inconsistency suggested the participation of other factors than direct mispairing in UV-induced transversion. Modification of DNA polymerase I by MNNG changed the ratio of polymerase to 3' leads to 5' exonuclease activity altering the fidelity of this enzyme, whereas MMS and UV-irradiation did not alter the fidelity of the enzyme.     

Production of Ochratoxin A by Aspergillus ochraceus Isolated in Japan from Moldy Rice

A simple thin-layer chromatography-fluorodensitometric method for quantitative analysis of ochratoxin A was developed. This method proved to be of use in investigating the production of the toxin and the nutritional factors affecting the toxin production by two strains of Aspergillus ochraceus isolated from moldy rice in Japan. These fungi produced large amounts of ochratoxin A in a nutrient solution containing 1% l-phenylalanine and 2% yeast extract.     

Differential inactivation of DNA polymerases α and β by aldehyde compounds

The effects of cyclohexanecarboxaldehyde, benzaldehyde and protocatechualdehyde on the activities of DNA polymerases α, β and E. coli DNA polymerase I were investigated. On direct addition of the aldehydes to the DNA polymerase assay mixture containing activated DNA or poly(dA) (dT)_12–18 as a template, DNA polymerase α was most strongly inhibited by the aldehyde compounds, while DNA polymerases β and I were resistant to such aldehyde inhibition. On preincubation of the enzymes with aldehyde, both DNA polymerases α and β were inactivated; however, DNA polymerase β was protected from the inactivation when activated DNA was added to the preincubation mixture. The inhibition of DNA polymerase α by aldehyde was noncompetitive with regard to the substrate dNTP and competitive with regard to the template DNA. The extent of inhibition of DNA polymerase α by aldehyde was partly reduced by the addition of cysteine to the reaction mixture.     

Patterns of arterial supply of the human fetal liver. The significance of the accessory hepatic artery

One or two aberrant hepatic arteries were found in 30% of human fetal livers. The liver received a triple or double arterial supply. The aberrant artery arises from the left gastric or superior mesenteric arteries and supplies an entire lobe or more without joining the branches of the usual hepatic artery in 38.5%. The artery has an important significance for the arterial supply of the fetal liver.     

Anaerobic Nitrogen-Fixing Consortia Consisting of Clostridia Isolated from Gramineous Plants

We report here the existence of anaerobic nitrogen-fixing consortia (ANFICOs) consisting of N₂-fixing clostridia and diverse nondiazotrophic bacteria in nonleguminous plants; we found these ANFICOs while attempting to overcome a problem with culturing nitrogen-fixing microbes from various gramineous plants. A major feature of ANFICOs is that N₂ fixation by the anaerobic clostridia is supported by the elimination of oxygen by the accompanying bacteria in the culture. In a few ANFICOs, nondiazotrophic bacteria specifically induced nitrogen fixation of the clostridia in culture. ANFICOs are widespread in wild rice species and pioneer plants, which are able to grow in unfavorable locations. These results indicate that clostridia are naturally occurring endophytes in gramineous plants and that clostridial N₂ fixation arises in association with nondiazotrophic endophytes.