Chimeric inheritance of organelle DNA in variegated leaf seedlings from inter-subgeneric crossing of azalea

The inheritance of organelle DNA was investigated using PCR–RFLP markers in reciprocal cross combinations of inter-subgeneric azalea hybrids between evergreen azaleas (Rhododendron nakaharai and its hybrids) and fragrant deciduous azaleas (R. arborescens and R. viscosum) for the purpose of breeding fragrant evergreen azaleas. The hybrid progenies included green leaf, pale green leaf, variegated leaf and albino seedlings. Most viable green leaf seedlings had inherited ptDNA from the deciduous parent and non-viable albino and pale green leaf seedlings had inherited ptDNA from the evergreen parent. On the other hand, variegated leaf seedlings had chimerically inherited ptDNA from both parents. Their green leaf segments had ptDNA from the deciduous parent, and the pale green and white segments had biparental or maternal ptDNA depending on the progeny. In this study, we obtained interesting inter-subgeneric azalea hybrid progenies that had chimerically inherited organelle DNA and had different colored leaf segments corresponding to the composition of ptDNA from each parent. These results suggest that variegated leaf progenies with chimeric ptDNA from both parents can be subsistent, whereas albino seedlings resulting from plastome–genome incompatibility between the plastid genome from evergreen azalea and the nuclear genome from deciduous azalea are non-viable.     

Protein synthesis and neurotrophin-dependent structural plasticity of single dendritic spines

Long-term potentiation (LTP) at glutamatergic synapses is considered to underlie learning and memory and is associated with the enlargement of dendritic spines. Because the consolidation of memory and LTP require protein synthesis, it is important to clarify how protein synthesis affects spine enlargement. In rat brain slices, the repetitive pairing of postsynaptic spikes and two-photon uncaging of glutamate at single spines (a spike-timing protocol) produced both immediate and gradual phases of spine enlargement in CA1 pyramidal neurons. The gradual enlargement was strongly dependent on protein synthesis and brain-derived neurotrophic factor (BDNF) action, often associated with spine twitching, and was induced specifically at the spines that were immediately enlarged by the synaptic stimulation. Thus, this spike-timing protocol is an efficient trigger for BDNF secretion and induces protein synthesis-dependent long-term enlargement at the level of single spines.     

Metabolism of 7-fluoro-6-(3,4,5,6-tetrahydrophthalimido)-4- (2-propynyl)-2H-1,4-benzoxazin-3(4H)-one (S-53482, flumioxazin) in the rat: II. Identification of reduced metabolites

On single oral administration of (14)C-S-53482 [7-fluoro-6-(3,4,5, 6-tetrahydrophthalimido)-4-(2-propynyl)-2H-1,4-benzoxazin-3( 4H)-one, Flumioxazin] labeled at the 1- and 2-positions of tetrahydrophthaloyl group to rats at 1 (low dose) or 100 (high dose) mg/kg, the radiocarbon was almost completely eliminated within 7 days after administration in both groups with generally very low residual (14)C tissue levels. The predominant excretion route was via the feces. The major fecal and urinary metabolites involved reduction or sulfonic acid addition reactions at the 1,2-double bond of the 3,4,5,6-tetrahydrophthalimide moiety and hydroxylation of the cyclohexene or cyclohexane ring. One urinary and four fecal metabolites were identified using chromatographic techniques and spectroanalyses (NMR and MS). Three of five identified metabolites were unique forms, reduced at the 1,2-double bond of the 3,4,5, 6-tetrahydrophthalimide moiety. On the basis of the metabolites identified in this study, the metabolic pathways of S-53482 in rats are proposed. To specify tissues forming reduced metabolites, an in vitro study was conducted. Reduction was found to take place in red blood cells.     

Methane concentration and emission as affected by methane transport capacity of plants in freshwater marsh

To elucidate effect of the CH₄ transport capacity of plants on CH₄ production and CH₄ emission, we measured CH₄ emission and the CH₄ transport capacity of plants as well as CH₄ and dissolved organic carbon (DOC) concentrations in porewater and redox potential in the freshwater marsh vegetated with Carex lasiocarpa, Carex meyeriana and Deyeuxia angustifolia. Although only 31% of CH₄ emitted was released via Deyeuxia angustifolia into the atmosphere compared to 72–86% via Carex plants and the CH₄ transport capacity of per stem of Deyeuxia angustifolia was only 8.0 g CH₄ stem^–1 h^–1 being equal to half for Carex plants, the flux of CH₄ emission from the Deyeuxia angustifolia marsh was just lower by 17–28% than those from the Carex marshes as the standing water depth decreased significantly from 15–20 to 5 cm, indicating that despite the poor CH₄ transport capability of Deyeuxia angustifolia partly reduced CH₄ emission via plants, however CH₄ emission was not greatly reduced as expected. This is because although the poor gas transport capability of Deyeuxia angustifolia lowered CH₄ emission to some extent, however it also decreased the input of O₂ into the rhizosphere via plants; the latter not only reduced CH₄ oxidation in the rhizosphere and/or rhizome but also lowered redox potential in the vertical profile resulting in an increase in CH₄ production potential and CH₄ concentration especially at 5 cm depth, which in turn facilitated CH₄ emission through diffusion in the Deyeuxia angustifolia marsh. This study suggests that the sharp decrease in the CH₄ transport capacity of plants did not necessary result in an expected lowering of CH₄ emission in the freshwater marsh.     

野生大豆、黑豆和大豆的异黄酮类成分比较

野生大豆主产于中国,古时为珍贵药材,但现代将其作药用的研究较少。以同样种植条件下收获的野生大豆、黑豆和大豆为材料,用HPLC法、凯氏定氮法和索氏残渣法分别测定其大豆异黄酮、蛋白质和脂肪含量,以此比较野生大豆、黑豆和大豆的药用价值。结果表明：12种大豆异黄酮类组分的总含量大小顺序为：野生大豆〉黑豆〉大豆;野生大豆和黑豆中黄豆苷和染料木苷含量特别突出,而且其相应的苷元含量也较高,大豆中则是丙二酰基化的黄豆苷和丙二酰基化的染料木苷含量特别突出,而其相应的苷元组分含量极低;相关性分析表明三种大豆的不同品种,大豆异黄酮总含量与其百粒重和脂肪含量呈极显著负相关,但与蛋白质含量的相关性不显著。结果说明野生大豆的药用研究应受到重视。     

Relative dominance of the mold fungus,<Emphasis Type="Italic">Raffaelea</Emphasis> sp., in the mycangium and proventriculus in relation to adult stages of the oak platypodid beetle,<Emphasis Type="Italic">Platypus quercivorus</Emphasis> (Coleoptera; Platypodidae)

Microorganisms associated with the oak platypodid beetle,Platypus quercivorus (Murayama), were isolated from the mycangium of adult females, from the proventriculus of adults of both sexes, and from galleries in the period before dispersal. Fungi isolated from female mycangia were separated into three groups:Raffaelea sp., yeasts (mainlyCandida spp.), and other species.Raffaelea sp. was isolated predominantly from the teneral stage to the dispersal stage, but was not isolated from the mycangia of mother beetles in new galleries. Yeasts were isolated in every beetle stage tested and their isolation rate was over 80% from the teneral stage to the dispersal stage. All three fungal groups were found in the female proventriculus.Raffaelea sp. was isolated only in the dispersal stage at a rate of 40%, whereas the isolation rate of yeasts gradually increased beginning in the mature stage and reached 100% in the rearing stage. In contrast, in the male proventriculus, onlyRaffaelea sp. and yeasts were isolated in the dispersal and rearing stages. The isolation rate in the rearing stage ofRaffaelea sp. was less than 20%, but that of yeasts was 100%, although these rates were almost the same in the dispersal stage.Raffaelea sp. and yeasts were also isolated from cradles containing eclosing pupae. These results suggest thatP. quercivorus acquiresRaffaelea sp. and yeasts in their mycangia from the cradles immediately after eclosion, and maintain them to the dispersal stage. Then, they transmit these fungi from old to new galleries by way of mycangia, and possibly the digestive system.     

Development of DNA markers that discriminate between white- and blue-flowers in Japanese gentian plants

We developed molecular markers for discrimination of white and blue flower color in Japanese gentian plants. White-flowered gentians can be classified into two types, based on genetic and physiological features. One type includes four allelic variations (gtmyb3-1, gtmyb3-2, gtmyb3-3, and gtmyb3-4) of an anthocyanin biosynthetic regulator gene (GtMYB3), distinguished by three PCR-based molecular markers. The other type contains a newly identified inactive allele (ans1) of the anthocyanidin synthase (ANS) gene with a premature stop codon generated from a 4-bp deletion in the second exon. The ans1 allele was distinguished from the active ANS allele by a cleaved amplified polymorphism sequence (CAPS) marker. The genotypes of 12 white-flowered gentian cultivars/lines could be identified and classified as either ans1 or gtmyb3 using these four molecular markers. No white-flowered gentians contained ans1 and gtmyb3 alleles simultaneously. The mutated ANS gene co-segregated with white flower color in an F₂ population, demonstrating that the CAPS marker is useful to discriminate between white and blue flowers in gentian. Markers to discriminate flower color in Japanese gentian will be useful for early selection of progeny and for breeding management.     

Effects of acidity of the water culture solution on uptake of nutrients by the root of Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa)

The condition around coniferous trees in the soil is becoming gradually acidic when acid rain falls continuously. Nutrient uptake by the roots of coniferous trees could be affected in such environmental change of root zone. The experiments of water culture of coniferous seedlings in modified systems were carried out using (2-and, 3-year-old) of Japanese cedar(Cryptomeria japonica) and, Japanese cypress(Chamaecyparis obtusa) that are the typical Japanese forest trees. Nine major nutrients such as Na⁺, NH₄ ⁺, K⁺, Ca²⁺, Mg²⁺, Cl^?, NO₃ ^?, PO₄ ^3?, and SO₄ ^2?, were given in the water culture solution and growth of trees was observed for two years. The aspects of nutrient uptake by these seedlings and the effects of acidity in culture solution were observed. The following results were obtained. 1) Japanese cedar of 50% and Japanese cypress of 30 % in tested seedlings could live for two years. 2) All Japanese cedar and cypress that started in the strong acidic condition ( pH=3.0) were dead within three months. 3) The minimum pH value in the acidic condition is estimated as 3.2 for these coniferous seedlings, and it means that they can live at least for two years in this condition. 4) The seasonal pattern of the uptake of nitrogen nutrient by Japanese cedar was determined.     

Impeded establishment of the infective stage of Trichinella in the intestinal mucosa of mice by passive transfer of an IgA monoclonal antibody

Our previous study showed that the IgA monoclonal antibody (mAb) HUSM-Tb1 forms immunoprecipitates on the cuticular surface of infective larvae of Trichinella britovi, and that intraperitoneal injection of this mAb to mice 5 hr before challenge infection confers a high level of protection against intestinal T. britovi. The same treatment produced a similar effect in BALB/c mice inoculated orally with Trichinella pseudospiralis larvae, indicating that the effects may be seen upon most members of the genus Trichinella. Worms recovered from the intestinal mucosa at 1 hr after challenge infection with T. pseudospiralis was few in mice passively immunized with the mAb, whereas a substantial number of worms were recovered from the mucosa of control groups. These results suggest that the IgA mAb impedes establishment of infective Trichinella worms in the intestinal mucosa. Trichinella worms inoculated orally into BALB/c mice vaccinated with ultraviolet-irradiated muscle larvae 3 weeks earlier were expelled between days 4 and 7 after challenge infection. Although the mAb HUSM-Tb1 originated from the mesenteric lymph node cells of mice vaccinated repeatedly with such irradiated larvae, IgA-mediated expulsion does not seem to play an important role in this vaccination model.     

Epidural administration of fixed volumes of xylazine and lidocaine for anesthesia of dairy cattle undergoing flank surgery

A modified method for epidural anesthesia in standing cattle undergoing flank surgery in which fixed volumes of xylazine and lidocaine were injected is described, along with results in 18 cattle. A Tuohy needle was inserted into the L1-2 intervertebral space from a dorsal midline approach, positioning of the needle tip in the epidural space was confirmed by use of the hanging drop technique, the needle was slowly advanced 7 to 10 mm to penetrate the epidural fat, and the anesthetic solution was then administered. In the initial 8 cattle, the anesthetic solution consisted of 1 mL of 2% xylazine and 4 mL of 2% lidocaine. However, 1 of these cattle became recumbent prior to surgery. Therefore, the dose of lidocaine was decreased, and in the subsequent 10 cattle, the anesthetic solution consisted of 1 mL of 2% xylazine and 3 mL of 2% lidocaine. Surgery was begun 30 minutes after epidural administration of anesthetic; surgery time ranged from 27 to 276 minutes. Sedation and anesthesia were adequate, except in 1 cow that received the lower dose of lidocaine and became recumbent during suturing of the incision. The modified epidural anesthesia technique with injection of fixed volumes of xylazine and lidocaine appears to be an adequate method for anesthesia of standing cattle undergoing flank surgery.