Biosystematic Studies on the genus Hemerocallis (Liliaceae) : I. Introgressive Hybridization between H. citrina v. vespertina and H. fulva sensu lato

The occurrence of a natural hybrid swarm between Hemerocallis citrina v. vespertina (Hara) M. Hotta and two varieties of H. fulva, i. e. , v. longituba (Miq.) Maxim. and v. disticha (Donn) M. Hotta, was first reported by Nakao and Yamashita (1956) from Matsunoki, located at the distance of 4 km east of Takayama City, Gifu Prefecture, Central Honshu.Based on the results of their investigation, it was concluded that this particular hybrid swarm found in a valley near Takayama represents an initial stage of introgression of genes of H. citrina v. vespertina into the population of H. fulva (Nakao and Yamashita, l. c. ) . Another example of introgressive hybridization in Hemerocallis, i. e., between H. middendorffii and H. yezoensis was reported by Kawano (1961) from Otanoshike near Kushiro City in Hokkaido. In both cases, the ecological disturbance of the habitats was deemed to be the maj or causes in breaking down the isolation barrier previously existing between these plants.In the present study, a natural hybrid population of Hemerocallis in the Matsunoki district was re-investigated from several new standpoints in order to know more precisely about the biological status of this particular population. In addition to the analyses of gross morphology and ecology, the karyotypes and meiotic behaviours of the chromosomes were studied. The pollen fertility, the setting rate and germination rate of the seeds were also examined. Furthermore, the electrophoretic banding patterns of acid-soluble protein extracted from the rhizomes of both parental and hybrid plants were likewise analyzed and compared with one another

Biosystematic Studies on the Genus Hemerocallis (Liliaceae) : II. Variation in Gross Morphology of the H. fulva Complex with Special Reference to the Identity of H. fulva v. longituba and v. disticha

Hemerocallis fulva sensu lato is known to be an exceedingly polymorphic species. In a recent taxonomic revision of the genus Hemerocallis in Japan and its neighbouring regions, Matsuoka and Hotta (1966) distinguished primarily by gross morphology, the following seven infraspecific taxa in the H. fulva complex: H. fulva L. v. fulva : v. Kwanso Regel ; v. sempervirP-ns (Araki) H. Hotta : v. littorea (Makino) M. Hotta ; v. longituba (Miq.) Maxim. ; v. disticha (Donn) M. Hotta ; and v. paucijlora M. Hotta & Matsuoka. However, there are still considerable discre· pancies in the taxonomic concept and treatment of this complex group. It has not been resolved, for example, whether or not several native Japanese taxa now referred to the H. fulva complex, such as v. disticha, v. longituba, etc. in the sense of Matsuoka and Hotta (1. c. ) should be referred to the same taxonomic group as the continental taxon, H. fulva v. fulva. This latter group also includes the double-flowered taxon, v. Kwanso which is widely distributed over the Japanese Islands excepting northern Hokkaido (cf. Ohwi, 1953, 1965; Kitamura et al., 1967).This paper particularly attempts to draw attention to the taxonomical identity of two native Japanese taxa, H. fulva v. longituba and v. disticha. In the present study; the variabilities of the plants, referred to the following four taxa of this complex, i. e., v. fulva, v. Kwanso, v. disticha, and v. longituba, are analyzed and compared, and their taxonomic status briefly discussed

Contrastive Analysis Between Japanese and American English Sound Systems : From an Articulatory Setting Perspective

論文Thesi

Analyzing genre-specific words of American TV dramas

論

Morphological features of lipid droplet transition during porcine oocyte fertilisation and early embryonic development to blastocyst in vivo and in vitro

Lipid content in mammalian oocytes or embryos differs among species, with bovine and porcine oocytes and embryos showing large cytoplasmic droplets. These droplets are considered to play important roles in energy metabolism during oocyte maturation, fertilisation and early embryonic development, and also in the freezing ability of oocytes or embryos; however, their detailed distribution or function is not well understood. In the present study, changes in the distribution and morphology of porcine lipid droplets during in vivo and in vitro fertilisation, in contrast to parthenogenetic oocyte activation, as well as during their development to blastocyst stage, were evaluated by transmission electron microscopy (TEM). The analysis of semi-thin and ultra-thin sections by TEM showed conspicuous, large, electron-dense lipid droplets, sometimes associated with mitochondrial aggregates in the oocytes, irrespective of whether the oocytes had been matured in vivo or in vitro. Immediately after sperm penetration, the electron density of the lipid droplets was lost in both the in vivo and in vitro oocytes, the reduction being most evident in the oocytes developed in vitro. Density was restored in the pronculear oocytes, fully in the in vivo specimens but only partially in the in vitro ones. The number and size of the droplets seemed, however, to have decreased. At 2- to 4-cell and blastocyst stages, the features of the lipid droplets were almost the same as those of pronuclear oocytes, showing a homogeneous or saturated density in the in vivo embryos but a marbled or partially saturated appearance in the in vitro embryos. In vitro matured oocytes undergoing parthenogenesis had lipid droplets that resembled those of fertilised oocytes until the pronuclear stage. Overall, results indicate variations in both the morphology and amount of cytoplasmic lipid droplets during porcine oocyte maturation, fertilisation and early embryo development as well as differences between in vivo and in vitro development, suggesting both different energy status during preimplantation development in pigs and substantial differences between in vitro and in vivo development.</p

Beneficial effect of tetrahydrobiopterin on ischemia-reperfusion injury in isolated perfused rat hearts

AbstractObjective: It has recently been proposed that nitric oxide synthase, in the presence of suboptimal levels of tetrahydrobiopterin, an essential cofactor of this enzyme, might favor increased production of oxygen radicals. The aim of this study was to clarify whether supplement with tetrahydrobiopterin would exert a cardioprotective effect against ischemia-reperfusion injury. Methods: Isolated perfused rat hearts were subjected to 30 minutes of global ischemia and 30 minutes of reperfusion at 37°C. Hearts were treated with tetrahydrobiopterin or vehicle for 5 minutes just before ischemia and during the first 5 minutes of the reperfusion period. Effects of tetrahydrobiopterin on left ventricular function, myocardial contents of lipid peroxidation and high-energy phosphates, and levels of lactate dehydrogenase and nitrite plus nitrate in perfusate during ischemia and after reperfusion were estimated and further compared with those of superoxide dismutase plus catalase or l-ascorbic acid. Results: Tetrahydrobiopterin and superoxide dismutase plus catalase both improved contractile and metabolic abnormalities in reperfused hearts. On the other hand, l-ascorbic acid at a dose having an equipotent radical scavenging activity with tetrahydrobiopterin did not significantly affect the postischemic changes. Although tetrahydrobiopterin and superoxide dismutase plus catalase significantly alleviated ischemic contracture during ischemia, diminished perfusate levels of nitrite plus nitrate after reperfusion were restored only with tetrahydrobiopterin. Conclusion: Results demonstrated that tetrahydrobiopterin lessens ischemia-reperfusion injury in isolated perfused rat hearts, probably independent of its intrinsic radical scavenging action. The cardioprotective effect of tetrahydrobiopterin implies that tetrahydrobiopterin could be a novel and effective therapeutic option in the treatment of ischemia-reperfusion injury.J Thorac Cardiovasc Surg 2002;124:775-8

Development to the blastocyst stage, the oxidative state, and the quality of early developmental stage of porcine embryos cultured in alteration of glucose concentrations in vitro under different oxygen tensions

BACKGROUND: Recent work has shown that glucose may induce cell injury through the action of free radicals generated by autooxidation or through hypoxanthine phosphoribosyltransferase inhibition. The effect of glucose during early in vitro culture (IVC) period of porcine embryos on their developmental competence, contents of reactive oxygen species (ROS) and glutathione (GSH), and the quality of the blastocysts yielded was examined. METHODS: In vitro matured and fertilized porcine oocytes were cultured for the first 2 days (Day 0 = day of fertilization) of IVC in NCSU-37 added with 1.5 to 20 mM glucose (Gluc-1.5 to -20 groups) or pyruvate and lactate (Pyr-Lac group). The embryos in all groups were cultured subsequently until Day 6 in NCSU-37 with 5.5 mM added glucose. The ROS and GSH level were measured at Day 1 and 2. DNA-fragmented nuclei and the total cell numbers in blastocyst were evaluated by TUNEL-staining at Day 6. RESULTS: Under 5% oxygen the blastocyst rates and total cell numbers in the blastocysts in all glucose groups were significantly lower than that in the Pyr-Lac group. Similar result in blastocyst rate was found under 20% oxygen (excluding the Gluc-10 group), but total cell numbers in the blastocysts was similar among the groups. At both oxygen tensions, the H2O2 levels of Day 1 embryos in all glucose groups were significantly higher than that in the Pyr-Lac group, while only the Gluc-1.5 group of Day 2 embryos showed a significantly higher H2O2 level than that in the Pyr-Lac group. The GSH contents of either Day 1 or Day 2 embryos developed under 5% oxygen were similar among the groups. Only the content of Day 2 embryos in 1.5 mM group was significantly lower than the embryos in the Pyr-Lac group under 20% oxygen. Total cell numbers in the blastocysts (except in the Gluc-20 group) were significantly lower in the embryos cultured under 20% oxygen than 5% oxygen. Only the Gluc-20 blastocysts developed under 5% oxygen showed significantly higher DNA fragmentation rate than those of Pyr-Lac blastocysts. CONCLUSION: These results show that a decrease in developmental ability of embryos cultured by use of glucose instead of pyruvate and lactate after the ferilization may be due to the rise in ROS generation in Day 1 embryos. Moreover, results from this study suggest that the concentration of glucose in the medium that can be used by the Day 1–2 embryos is limited to 3.5 mM and exposure to higher glucose concentrations does not improve embryo development

The IT-Distribution Systems of Farm Products Based on Regional Producing and Consuming Scheme.

本論文は日本の農と食の問題点をふまえ,「地産地消」に向けた新しい農産物流通のシステムについて検討する.このシステムの本質的な要因は食品・農産物のトレーサビリティである.その実際の取り組みや実証実験などの事例に基づき,消費者と生産者の交流と関係改善を通じて食生活の見直しや日本農業の活性化を図る糸口を探る.In this paper, we discuss new distribution systems of farm products based on a regional producing and consuming scheme, in light of Japanese agriculture and food problems. The essential factor of the systems is traceability of foods and farm products. Studying the actual cases and the feasibility tests, we investigate ways to change our eating habits and to make Japanese agriculture vital through communication between consumers and producers to improve their relationship