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Yamagata prefecture, facing the Japan Sea, is one of the heavy snow fall regions of the world. Around half of the annual precipitation of around 3000 mm falls in winter as snow, producing snow covers of more than three meters depth. However, air temperature is around 0°C in winter and therefore relatively warm. Hence, snow density becomes 0.5 g/cm³ already early in the snow accumulation phase. To qualify and quantify interactions, three spots on a slope, forested with Japanese cedar (Cryptomeria japonica), have been selected to compare relationships on top, at the middle and at the bottom of snow covered slopes. The site represents the majority of mountain forests in north-eastern Japan. Monitoring soil and air temperature as well as precipitation and soil moisture we found strong interactions between the three hydrological regimes (precipitation, snow cover and soil) in winter. Soil did not freeze and hence volumetric soil moisture content changed during the winter season. Several sharp significant increases of soil moisture have been measured before the snow melt period even started. High rates of soil moisture increase together with an increase of Snow Water Equivalent (SWE) have been found to be caused by rain-on-snow events. In contrast, smaller rates of soil moisture increase in peaks were correlated with a decrease in SWE and therefore a snowmelt process. The interactions of snow cover and soil have been found to be different in the three different spots at the slope. Soil at the bottom of a slope reacts significantly to the highest number of events; soil on the slope reacts only to some events, but more intensively. Thus, most of the water is moving within the snowpack down the slope, increasing the SWE. Thereafter water reaches the soil surface and infiltrates it. This has been found to be also one reason for the formation of depth hoars and therefore the risk of avalanches.To conclude, hydrological regimes in north-eastern Japan interact during the whole year due to winter air temperatures around 0°C and soil which does not freeze. The shape of peaks in soil moisture can be used to distinguish between rain and snowmelt causing the soil moisture increase. Various preferential flow patterns at different spots on a slope are an excellent basis for further studies and a basis for further monitoring and modelling.

Lignin content, composition, and linkage types were investigated in pear fruit cultivars and related species. Lignin content increased during early stages and then decreased toward ripening in the core and flesh of "Gold Nijisseiki" and "Alexandrine Douillard". The lignin content was highest at harvest in Chinese quince. Only trace amounts of lignin were detected in apple flesh. The lignin content was low in Japanese pears "Ohshu", "Hosui", and "Kosui", and the noncondensed lignin index was high in flesh. The lignin type was guaiacyl-syringyl (GS) in these pears and related species. The S/G ratio at harvest varied widely (0.75-2.64) and increased during early stages and remained constant toward harvest in "Gold Nijisseiki" and "Alexandrine Douillard". "Gold Nijisseiki" and "Alexandrine Douillard" were determined to be G- and S-lignin-rich types, respectively. β-Aryl ether, phenylcoumaran, and resinol interunit linkage types were detected among monolignol bonds, and β-Aryl ether units were the main linkages in the pear.

Different weeding frequencies (WFs)―0WF, 2WF, 4WF, 6WF, and 8WF―were adopted in an organic rice field to investigate their influence on weed types, rice and weed biomass, rice tiller and weed number, N concentration, and N uptake. The study field was located in Tsuruoka, Yamagata, Japan. Rice (cv. Sasanishiki) was planted from May to September 2019, and all weeding events were carried out until 49 days after transplantation (DAT) using a rotary weeder. Rice and weed samples were collected at 60, 88, and 110 DAT. Echinochloa crus-galli (E. crus-galli), Schoenoplectus juncoides, and Monochoria vaginalis (Burm. f.) were the most commonly found weeds. High weed diversity was observed at both 6WF and 8WF, E. crus-galli was the dominant weed at 0WF. Compared to 0WF, 2WF displayed a significantly decreased weed biomass. However, at 8WF, the weed biomass was reduced by 79.0%, the rice biomass was increased by 277%, and the rice tiller number was almost three times higher than that at 0WF and 110 DAT. Compared to 0WF, a significantly increased rice N uptake was observed at 4WF, and rice N uptakes achieved at 6WF and 8WF were two and four times higher than those at 0WF, respectively. Higher weeding frequencies provide notable benefits in suppressing weeds and supporting rice growth, especially in N uptake competition with weeds.

The effects of exogenous GA4+7 and BA + CPPU treatments at flowering on fruit traits, lignin, and metabolome were investigated in fruit of Japanese pear “Gold Nijisseiki”. Analysis of fruits in all treatments showed that both total and noncondensed lignin content increased early in fruit development and decreased toward harvest and that the core had higher lignin content than the flesh. The core of BA + CPPU-treated fruit had higher maximum total lignin content than did GA4+7-treated and control fruit at early fruit development. At harvest, the total lignin and noncondensed lignin content of BA + CPPU-treated fruit was higher than that of GA4+7-treated and control fruit. The lignin was composed of guaiacyl-syringyl types and the syringyl/guaiacyl (S/G) ratio increased during early stages and remained relatively stable toward harvest. These results suggest that exogenous GA4+7 and BA + CPPU treatment affected only the lignin content, not the S/G ratio. In total, 122 substances were used for metabolome analysis. Partial least squares discriminant analysis first divided substances into clusters corresponding to core and flesh and then separated the clusters of substances associated with GA4+7 treatment from those associated with the BA + CPPU treatment and control. Of these 122 metabolites, 40 were subjected to hierarchical cluster analysis. Among these, 8 metabolites were more abundant in the pear fruit core. The remaining 32 metabolites were more abundant in flesh and differed in abundance among treatments. The functional metabolite arbutin was more abundant in core than in flesh. In contrast, beta-nicotinamide ribotide was more abundant in flesh than in core.

Ripening characteristics and pigment changes were investigated in &lsquo, La France&rsquo, &lsquo, Gorham&rsquo, and their russeted sports &lsquo, Gold La France&rsquo, and &lsquo, Grand Champion&rsquo, pears. Fruit were harvested at commercial maturity and ripened at 20 &deg, C. In all cultivars, fruit softening was concomitant with a burst in ethylene production. Interestingly, such changes were delayed in russet pear when compared with their wild-types. Chlorophyll level in russet pear at harvest was the same as in the wild-type. In &lsquo, pears, its level rapidly decreased during ripening. Ethylene or 1-methylcyclopropene (1-MCP) did not affect the color and pigments in &lsquo, pears. In contrast, in &lsquo, pears, chlorophyll degradation was suppressed by 1-MCP treatment, but not completely. These results suggested that chlorophyll degradation was regulated by both ethylene-dependent and ethylene-independent means. The influence of ethylene on the expression of chlorophyll-degradation-related genes seemed to be similar in both russet and wild-type. The Stay green-1 gene was stimulated by ethylene and suppressed by 1-MCP treatment. In contrast, little effect of ethylene or 1-MCP was observed on chlorophyllase 1, pheophytinase, pheophorbide a oxygenase, and NYC1-like genes.

After harvesting, pears undergo numerous biochemical processes and frequently fail to reach acceptable quality. The uses of packaging and ethylene (C 2 H 4 ) absorber are regarded as well-known ways to solve that problem. However, accumulated CO 2 in the package can promote the symptoms of internal browning on pear flesh also exacerbated by too low O 2 concentrations. To inhibit the symptoms in ‘Silver Bell’ pear for a long period, we utilized CO 2 adsorbent, CO 2 adsorbent plus C 2 H 4 adsorbent, and without both adsorbents in a bag to investigate their effects on internal browning development for 7 months in cold-storage. We found both adsorbents successfully reduced CO 2 and C 2 H 4 levels even though the incidences were visually found at 3 months of storage. Most severe internal browning was observed on CO2 adsorbent-untreated pears under high CO 2 levels (7-9%) increasing since the beginning of storage. Therefore, there were no significant differences on the color and flesh firmness among the treatments, except controls, during cold-storage. Internal browning-affected pears showed harder flesh, greener and darker color compared with unaffected pears. Interestingly, control samples also suffered internal browning under low CO 2 ( 0.1%) and high O 2 ( 20.5%) concentrations after 5 months in storage with medium damage levels. We conclude that the uses of CO 2 and C 2 H 4 adsorbents successfully lowered CO 2 and C 2 H 4 levels in the bags during cold storage, but the both failed to prevent an internal browning development because too long storage period eventually caused internal browning.

Fruit size is one of the most important traits in fruit trees. We found a bud sport mutant bearing giant fruits of pear in an orchard in Yamagata prefecture, Japan. The fruit weight of this mutant was more than twice that of an original cultivar ‘La France’. The size of the receptacle was already larger in the mutant than in the original cultivar at full bloom, and size differences between the mutant and the original cultivar were observed throughout fruit development. Microscopic observation of fruit cortex cells revealed that the size of cells was larger in the mutant than in the original cultivar, and that the number of cells was comparable between the mutant and the original cultivar. Flow cytometric analysis revealed an increase in the number of cells having doubled amounts of DNA (4C cells) in the fruit cortex, but such an increase was not found in leaves, suggesting chimeric polyploidization or endoreduplication in fruits of the mutant. Mutant fruits exhibited significantly higher titratable acidity and lower firmness than those of the original cultivar. These differences were observed from 110 days after full bloom to 165 days (the commercial harvesting time). However, the concentration of soluble solids was not different between the mutant and the original cultivar. There were no significant differences in polyuronide contents between the mutant and the original cultivar fruits, but hemicellulose content in fruits of the mutant was significantly lower than in those of the original cultivar.

We investigated the effects of symbiotic association between a plant and an arbuscular mycorrhizal fungus (AMF) on the abundance of aboveground foliar-feeding insects that differed in feeding mode and their predator. We examined effects on insect abundance as the result of AMF-related changes in the quality and quantity of plants in the field. The numbers of three insects with different foliar-feeding mode (phloem feeder, chewer, and cell-content feeder) and their generalist predator Orius sauteri Poppius on soybean Glycine max (L.) Merrill with and without the AMF Gigaspora margarita Becker & Hall were compared over time. Symbiotic association between the AMF and the soybean increased shoot biomass, the concentration of phosphorus in the soybean, and the abundance of the phloem feeder Aulacorthum solani Kaltenbach, but did not affect the abundance of generalist chewers. In addition, the effects of the symbiotic association on the abundance of cell-content feeding Thrips spp. and the generalist predator O. sauteri differed between sample dates. These results indicated that the effects of the symbiotic association on the number of foliar-feeding insects depended on feeding mode and the number of predators.

The improvement of host plant growth resulting from mycorrhizal colonization often affects the viability of above-ground herbivorous insects. Conversely, the effects of herbivorous insects on plant growth may indirectly affect below-ground microorganisms. This study investigated the effects of herbivorous insects on arbuscular mycorrhizal (AM) colonization of soybean (Glycine max Merr.). Seeds of soybean were sown in soil inoculated with the AM fungus Gigaspora margarita Becker & Hall and grown in growth chambers. At 39 days after inoculation (DAI), a larva of the common cutworm (Spodoptera litura Fabricius) was placed on a leaf of each soybean plant for 5 days. AM colonization of soybean on 39 DAI was 21%. Although not evident by 62 DAI, by 77 DAI there was a statistically significant increase in AM colonization in plants subjected to herbivory by S. litura relative to control plants. Leaf removal at 46 DAI was also associated with increased AM colonization at 78 DAI. These results suggest that herbivory...

Black spot disease is one of the most serious diseases in Asian pear cultivation, with the commercial cultivar Nijisseiki being susceptible. Ethylene is known to play major roles in regulating plant defense responses against various pathogens. We investigated the relationship between ethylene synthesis and black spot disease in ‘Nijisseiki’ pear leaves by treatment with an analog of ethylene and 1-methylcyclopropene (1-MCP), an inhibitor of ethylene action. Interestingly, both treatments enhanced black spot disease symptoms. Both treatments also increased ethylene production in accordance with disease symptoms through altered gene expression of ethylene biosynthetic enzymes, especially 1-aminocyclopropane-1-carboxylate (ACC) synthase genes (PpACS3 and 4). Chemical names used: 1-methylcyclopropene (1-MCP), 1-aminocyclopropane-1-carboxylate (ACC).

夏秋作における有機および慣行栽培ミニトマトの品質成分の実態を明らかにするため，有機および慣行栽培ミニトマトを各16圃場から試料を得，果実特性とアスコルビン酸，リコペン，β-カロテン，糖類，遊離アミノ酸，クエン酸含量およびエチレン生成量を調査した．有機栽培ミニトマトでは，慣行栽培のものと比較して，果実硬度が小さく，アスコルビン酸とリコペン含量が有意に高かった．また，エチレン生成量が有意に低かった．これらの差違の原因として，実際に流通している有機と慣行栽培ミニトマトには熟度に差がある可能性が推察された．

Apple Malus X domestica fruitlet abscission is preceded by a stimulation of ethylene biosynthesis and a gain in sensitivity to the hormone. This phase was studied by a differential screening carried out by cDNA-AFLP in abscising (AF) and non-abscising (NAF) fruitlet populations. Fifty-three primer combinations allowed for the isolation of 131, 66 and 30 differentially expressed bands from cortex, peduncle and seed, respectively. All sequences were then classified as up- or down-regulated by comparing the profile in AFs and NAFs. Almost all of these sequences showed significant homology to genes encoding proteins with known or putative function. The gene ontology analysis of the TDFs isolated indicated a deep change in metabolism, plastid and hormonal status, especially auxin. Furthermore, some common elements between abscission and senescence were identified. The isolation of the full length of one of these TDFs allowed for the identification of a gene encoding an auxin hydrogen symporter (MdAHS). Bioinformatic analysis indicated that the deduced protein shares some features with other auxin efflux carriers, which include PINs. Nevertheless the 3D structure pointed out substantial differences and a conformation largely dissimilar from canonical ion transporters. The expression analysis demonstrated that this gene is regulated by light and development but not affected by ethylene or auxin.

Nickel oxide (NiO) is one of the important industrial materials used in electronic substrates and for ceramic engineering. Advancements in industrial technology have enabled the manufacture of ultrafine NiO particles. On the other hand, it is well-known that nickel compounds exert toxic effects. The toxicity of nickel compounds is mainly caused by nickel ions (Ni(2+)). However, the ion release properties of ultrafine NiO particles are still unclear. In the present study, the influences of ultrafine NiO particles on cell viability were examined in vitro to obtain fundamental data for the biological effects of ultrafine green NiO and ultrafine black NiO. Ultrafine NiO particles showed higher cytotoxicities toward human keratinocyte HaCaT cells and human lung carcinoma A549 cells than fine NiO particles and also showed higher solubilities in culture medium (Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum) than fine NiO particles. In particular, the concentration of Ni(2+) released into the culture medium by ultrafine green NiO was 150-fold higher than that released by fine green NiO. The concentrations of Ni(2+) released by both types of NiO particles in an aqueous solution containing amino acids were remarkably higher than those released by NiO particles in water. Moreover, we prepared a uniform and stable dispersion of ultrafine black NiO in culture medium and examined its influence on cell viability in comparison with that of NiCl(2), a soluble nickel compound. A medium exchange after 6 h of exposure resulted in a loss of cytotoxicity in the cells exposed to NiCl(2), whereas cytotoxicity was retained in the cells exposed to NiO. Transmission electron microscope observations revealed uptake of both ultrafine and fine NiO particles into HaCaT cells. Taken together, the present results suggest that the intracellular Ni(2+) release could be an important factor that determines the cytotoxicity of NiO. Ultrafine NiO is more cytotoxic than fine NiO in vitro.

We focused on modification of polyuronides during ripening to clarify the mechanisms involved in peach fruit softening and textural changes. Fruit of the stony hard type peach ‘Miharu Hakuto’ softened during ripening in ethylene-free air, but did so more slowly than the melting type peach ‘Kawanakajima Hakuto’. In addition, the stony hard type peach in ethylene-free air did not develop a melting texture, and solubilization of polyuronides did not occur during ripening, although the fruit gradually softened. Exposure of the stony hard type peach to continuous ethylene promoted fruit softening and development of a melting texture and induced the solubilization of polyuronides to the same levels as in the melting type peach. Expression of the polygalacturonase gene PpPG2 was higher than that of PpPG1 and PpPG3 , during ripening in both cultivars. PpPG2 -mRNA in the melting type peach showed a slight accumulation at harvest and markedly increased during ripening at 20 °C. Expression of PpPG2 in the stony hard type peach in ethylene-free air was considerably lower than that in the melting type peach, and ethylene exposure of the stony hard type peach up-regulated the mRNA level of PpPG2 to that of the melting type peach. The mRNAs of two pectin methylesterase genes, PpPME1 and PpPME2 , in stony hard type peach in ethylene-free air were reduced during ripening at 20 °C as compared with these genes in the melting type peach. Continuous ethylene exposure up-regulated PpPME2 mRNA in the stony hard type peach. The mRNAs of two pectate lyase genes, PpPL1 and PpPL2 , were expressed constitutively throughout ripening in both cultivars. These results show that ethylene plays an important role in the solubilization of polyuronides and development of a melting texture in peach fruit. In addition, PpPG2 and PpPME2 might be involved in the solubilization of polyuronides in peach fruit.

The interfacial bonding of carbon fiber and epoxy matrix modified by fullerene nanoparticles has been investigated using both transverse fiber bundle tension test and transverse tension test of unidirectional composites. It has been found that the incorporation of fullerene nanoparticles in a proper content, such as 2 wt%, led to a substantial increase in fiber/matrix bond strength. The improvement of interfacial bonding is ascribed to the toughening effect of epoxy matrix endowed by fullerene nanoparticles, which may contribute to suppress the fracture of interface layer around fibers by the mechanism of energy dissipation.

Neointimal formation after percutaneous coronary intervention (PCI), termed restenosis, limits therapeutic revascularization. Since it is now known that vascular injury involves an inflammatory response, we examined the role of tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in the neointimal formation after injury.Control (BALB/c), TNF-alpha-deficient (Tnf(-/-)), IFN-gamma-deficient (Ifng(-/-)), or double-deficient (Tnf(-/-)Ifng(-/-)) mice were subjected to wire-mediated vascular injury of the right femoral artery. Neointimal formation after injury was significantly reduced after the injury in the Tnf(-/-)Ifng(-/-) mice, compared to that in the control, Tnf(-/-), and Ifng(-/-) mice. Immunohistochemical analysis showed that TNF-alpha and IFN-gamma were expressed in neointimal lesions in the control mice, but not in mice with deficiency of the corresponding cytokine. No significant difference in re-endothelialization was observed among these groups. The number of proliferating cell nuclear antigen in the neointimal lesions was significantly decreased in the Tnf(-/-)Ifng(-/-) mice. Bone marrow transplantation experiments revealed that deficiency of TNF-alpha and IFN-gamma specifically in bone marrow cells significantly inhibited neointimal formation after vascular injury.The absence of TNF-alpha and IFN-gamma in bone marrow cells synergistically inhibits neointimal formation following vascular injury, and thus, may provide new insights into the mechanisms underlying restenosis after PCI.

An Agrobacterium-mediated transformation system was developed for pear (Pyrus communis L., cv. ‘La France’) with leaf discs used as explants. This system was successfully used to introduce the sense and antisense cDNA that encode an ACC oxidase (ACO) cloned from the ripe pear fruit into the pear genome. The transcriptional activity of the transgene and endogenous gene in the transgenic shoots were detected by the strand-specific probes used in RNA blot analysis. The gene co-suppression was found in almost all antisense lines and one sense line, while the over-expression was observed in other sense lines. The ethylene production in transgenic shoots was consistent with the expression of sense-strand ACO transcription when the samples were incubated in 1 mM ACC, which is a unique substrate of ACO. Ethylene production in in vitro shoots was reduced by 85% in an antisense line. In vitro flowering and abnormal rooting was found in some antisense shoots. The relationships between the ethylene and above phenomena were also discussed.

Metabolites in the fruits of edible plants include sweet sugars, visually appealing pigments, various products with human nutritional value, and biologically active plant hormones. Although quantities of these metabolites vary during fruit development and ripening because of cell division and enlargement, there are few reports describing the actual dynamics of these changes. Therefore, we applied multiple metabolomic techniques to identify the changes in metabolite levels during the development and ripening of pear fruits (Pyrus communis L. 'La France'). We quantified and classified over 250 metabolites into six groups depending on their specific patterns of variation during development and ripening. Approximately half the total number of metabolites, including histidine and malate, accumulated transiently around the blooming period, during which cells are actively dividing, and then decreased either rapidly or slowly. Furthermore, the amounts of sulfur-containing amino acids also increased in pear fruits around 3-4 months after the blooming period, when fruit cells are enlarging, but virtually disappeared from ripened fruits. Some metabolites, including the plant hormone abscisic acid, accumulated particularly in the receptacle prior to blooming and/or fruit ripening. Our results show several patterns of variation in metabolite levels in developing and ripening pear fruits, and provide fundamental metabolomic data that is useful for understanding pear fruit physiology and enhancing the nutritional traits of new cultivars.

A laser Doppler vibrometer (LDV) technique was used to monitor ripening behaviour and a reciprocal model was developed to simulate the ripening process of pear fruit stored for various periods at low temperature. Over a period of separate growing seasons ‘La France’ pears were harvested at the stage considered most favorable for the development of high quality fruit and stored in air at 1 °C for intervals from 2 weeks to 6 months. After the low temperature storage treatment the pears were maintained at 20 °C and continuously monitored for flesh elasticity and texture evaluated by sensory evaluation. The laser Doppler vibrometer (LDV) was employed to detect responses to imposed vibration of intact pears and an FFT-analysis was used to estimate the second resonant peak used for the calculation of the elasticity index E . Pears stored for relatively short intervals (from 2 weeks to 2 months) developed textural qualities consistent with consumer's expectations and as these fruit ripened there was a steady decline in the E -value. The decline in the elasticity index E complied with both the reciprocal and conventional exponential models; however, the reciprocal model more consistently reflected the experimental data. Fruit stored for over 4 months failed to ripen or developed an undesirable skin color. Typically these fruit developed a texture that made them unacceptable for consumption and as a result such pears were of no commercial value. LDV analysis showed that these fruit developed an irregular pattern in the elasticity index over the course of the post-storage ripening interval. A normalized curve was proposed to compare the E declination for pears with different initial elasticity indices when subjected to various storage periods. Since changes in the fruit flesh elasticity index reflect s characteristics of cell wall structure and cell turgor, the use of LDV measurements of intact fruit may be a useful approach for exploring, non-destructively, the progression of metabolic changes in fruit cell walls associated with ripening.

Pear fruit usually soften and develop a melting texture when harvested at the mature green stage and ripened. The reason why the fruit does not fully ripen on the tree is unknown. To clarify this, our attention was directed to the continuous supply of assimilates and/or other substances into the fruit via phloem transport. To determine the effect of inhibiting phloem transport on fruit ripening on the tree, a girdling treatment was applied to the branch above the abscission zone of 'Bartlett' pear (Pyrus communis L.). Girdling significantly enhanced the ethylene production of fruit on day 12 compared with control fruit. Fruit softening was also stimulated by girdling. On day 8, flesh firmness was similar in treated fruit on the tree and in fruit off the tree, and was significantly lower than that of untreated fruit on the tree. The patterns of transcript accumulation for the ethylene biosynthetic [1-aminocyclopropane-1-carboxylate (ACC) synthase (PcACS) and ACC oxidase (PcACO)] and polygalacturonase (PcPG1 and PcPG3) genes showed good correspondence with ethylene production and fruit softening, respectively. Thus, fruit ripening on the tree was stimulated via ethylene by girdling on the branch above the abscission zone of fruit to interrupt phloem transport. Assimilates and/or other substances in phloem sap may prevent fruit ripening on the tree.

Storage of horticultural products in closed rooms often causes deterioration of the quality and shortens the storage period because of changes in the room atmospheres caused by respiration and secondary metabolism during storage. In our study, fruits or cut flowers were stored independently at 13-23°C in a closed chamber, and the effects of photocatalytic oxidation by TiO 2 on quality maintenance of horticultural products and changes in gas environment in the chamber were evaluated. Ethylene and carbon-dioxide concentrations in the chamber of the control sample (without TiO 2 photocatalyst) increased rapidly during storage, while those of treatment (with TiO 2 photocatalyst) increased gradually. Both fruit ripening and senescence of cut flowers stored with TiO 2 photocatalyst were delayed compared to those of control samples. When 'Otome-gokoro' strawberry fruits were stored at 13°C for 8 days, a decrease in sucrose concentrations was observed during storage, irrespective of photocatalytic oxidation. Hexose concentrations in the control did not change during storage, whereas those of treatment slightly increased. As a result, there was no significant decrease in the total sugar (sucrose + hexose) concentrations of treated strawberries. Malic acid concentrations also decreased during storage, irrespective of photocatalytic oxidation, whereas citric acid concentrations did not differ significantly between treated and untreated samples. Our results show that horticultural products can be effectively stored even in closed rooms by using TiO 2 photocatalytic oxidation.

We investigated the effects of the storage period on the molecular distribution profile of pectic and hemicellulosic polysaccharides in ‘Maruguerite Marillat’ and ‘La France’ pears. After storage of fruit of both cultivars for 1 month (short-term storage) at 1 °C, or 4 months (long-term storage) for ‘Marguerite Marillat’ and 5 months (long-term storage) for ‘La France’, the fruit were transferred to 20 °C for ripening. Based on the firmness of the flesh, five fruit at different stages of softening (from hard to soft) from each storage condition were selected for analysis. The fruit softened after transfer to 20 °C after storage at 1 °C, independently of the cultivar or storage period. However, after long-term storage, the fruit did not achieve the buttery and juicy texture known as the melting texture, whereas after short-term storage, fruit of both cultivars reached these textures. When the fruit developed the melting texture, both the uronic acid and total sugar components of the water-soluble polyuronides (WSP) showed striking molecular-mass downshifts, concomitant with increases in the levels of smaller polymers. In over-ripe fruit, the molecular-mass downshifts were extensive. In fruit that had been subjected to long-term storage, the uronic acid component of the WSP also showed a tendency toward molecular-mass downshifts as the fruit softened. However, no relationship was observed between fruit softening and changes in the molecular-mass distribution of the total sugar component. In ‘Marguerite Marillat’ and ‘La France’ fruit after short-term storage, the molecular-mass distribution of the total sugar and xyloglucan components of the hemicellulosic polysaccharides did not change significantly until the fruit developed the melting texture. After that point, the peak shifted greatly toward the low-molecular-mass region. In fruit after long-term storage, the total sugar and xyloglucan components also showed molecular-mass downshifts. However, the extent of the downshifts was still larger in fruit after short-term storage than in those after long-term storage. These results suggest that reduced depolymerization of pectic and hemicellulosic polysaccharides is related to an inferior fruit texture after prolonged storage.

‘La France’ pear (Pyrus communis L.) fruit stored at 1°C for 1 month (short-term storage) before transfer to 20°C softened and developed a melting texture during ripening, whereas fruit stored for 5 months (long-term storage) before transfer to 20°C softened but did not develop a melting texture. To clarify the mechanisms involved in fruit softening and textural changes, the cDNAs encoding cell-wall hydrolases were isolated by RT-PCR, and their expression and localization were investigated in ‘La France’ pears. Genes encoding three polygalacturonases (PG; EC 3.2.1.15), four pectin methylesterases (PME; EC 3.1.1.11), one α-arabinofuranosidase (ARF; EC 3.2.1.55), three β-galactosidases (GAL; EC 3.2.1.23), and two endo-1,4-β-d-glucanases (Cel; EC 3.2.1.4) were isolated. Among these 13 isolated genes, PcPG1 was the only gene for which the mRNA expression levels increased in both the short- and long-term stored fruits. This suggested that PcPG1 is involved in fruit softening rather than in the development of the melting texture. In contrast, the expression levels of PcPG3, PcPME1, PcPME2, PcPME3, PcGAL1, PcGAL2, and PcCel2 increased during ripening only in the short-term stored fruit. These genes might thus be involved in the development of the melting texture.

In the last decade, application of fullerenes has been proposed actively in a wide range of areas, and recent developments suggest that many of those applications are to be practical technologies. However, there has been no large‐scale production enterprise for commercial usage of fullerenes. High production cost and limited availability of fullerenes have been the main obstacle in the development of the Fullerene Market. Improved flame‐based technology leads to the most feasible process for mass production of fullerenes, since it is a continuous process and uses inexpensive hydrocarbons as its starting materials. In May 2003, we started fullerene production in tons and more to supply fullerenes with reasonable price as practical materials for industries.

Green banana fruit, which had been exposed to ethylene for 24 h, were kept in air or 60% CO2 + air. In control fruit, a typical climacteric curve of respiration was observed. Citrate and malate continued to accumulate throughout the experimental period. This suggests a glycolytic carbon flow exceeding that of the TCA cycle throughout the ripening period. The content of 2-oxoglutarate and activity of NADP-linked isocitrate dehydrogenase (NADP-IDH) changed approximately in parallel to the climacteric pattern of respiration. By contrast, with the CO2 treatment, the respiratory climacteric was suppressed along with decreasing contents of pyruvate, 2-oxoglutarate, and malate. However, there was accumulation of citrate and succinate, with citrate mostly equal to and the latter exceeding levels in control fruit. Activity of NADP-IDH was strongly suppressed by CO2 exposure. In addition, high concentrations of CO2 decreased the oxidative activity of NADP-IDH in an in vitro assay, indicating a decrease in production of 2-oxoglutarate.

[..] We cloned the cDNAs encoding ACC synthase and ACC oxidase from ripe pear (cv. 'La France') fruits, designated LF-ACS1 and LF-ACO1, respectively, and introduced them into the 'La France' pear in either sense or antisense orientation using Agrobacterium-mediated leaf disc transformation. T-DNA integrations into the pear genome were confirmed by PCR and Southern analysis. In transgenic lines containing sense or antisense LF-ACO1 transgenes, the expression of endogenous ACC oxidase gene was examined by Northern analysis. The results demonstrated that the expression of ACC oxidase was inhibited in nearly all antisense lines and in one sense line. Ethylene production in the presence of ACC, a unique substrate of ACC oxidase, was lower in these transgenic shoots.

Changes in the activity and some characteristics of NADP-dependent isocitrate dehydrogenase (NADP-IDH, EC 1. 1. 1. 42) of banana [Musa spp (AAA group, Cavendish subgroup)] fruit during postharvest ripening were investigated. The activity was about 2.7-fold higher in yellow (ripe) fruit than in mature green fruit. These activities were NADP-dependent in both stages of fruit, but the degree of Mg2+ dependency was slightly higher in mature green fruit than in yellow fruit. The Km values of the enzyme for DL-isocitrate in mature green and yellow fruit were 48. 4μM and 59.5μM, respectively. While the value for NADP+ in mature green fruit was 6.14μM, that was 11.56μM in yellow one. The elution pattern of gel filtration showed that yellow fruit have different peaks for these activities from mature green fruit. From these results, NADP-IDH in banana fruit may change their isozymes which have different Km values during postharvest ripening.

The changes in activity of NADP-linked isocitrate dehydrogenase (NADP-IDH, EC 1.1.1.42) of banana fruit (Musa spp. [AAA group, Cavendish subgroup]) during postharvest ripening were investigated. The activity of NADP-IDH in the flesh of mature green fruit was low during the preclimacteric stage at 20°C. However, the enzyme activity in fruit treated with propylene increased during ripening to more than twice that of the control. The contents of pyruvate and 2-oxoglutarate also increased in propylene treated fruit. The increase in 2-oxoglutarate is attributed to the rise in NADP-IDH activity because they both coincided with the increase of respiration rate during postharvest ripening. Hence, NADP-IDH is considered to play an important role in the postharvest ripening of banana fruit.

We investigated the relationship between flesh firmness and the cell wall polysaccharides of ‘Marguerite Marillat’ and ‘La France’ pears that had retained or lost their ripening capacity. In both cultivars, fruit softened and reached a buttery and juicy texture after short-term storage (1 month at 1 °C), while fruit softened but never reached that texture after long-term storage (4 months for ‘Marguerite Marillat’ or 5 months for ‘La France’ at 1 °C). In ‘Marguerite Marillat’ pears, the water-soluble polyuronide (WSP) levels in fruit after long-term storage tended to be lower than those after short-term storage, when compared with fruit having similar flesh firmness. In ‘La France’ pears, lower flesh firmness correlated with higher WSP content in fruit after short-term storage, while the lower the flesh firmness, the lower the WSP content in fruit after long-term storage. The relationship between flesh firmness and alkali-soluble polyuronide (ASP) content showed the highest correlations in both cultivars among cell wall polysaccharides determined in this study. Lower flesh firmness correlated with lower ASP content, independent of cultivar and storage period. Fruit, after short-term storage, contained more ASP than after long-term storage in both cultivars, when compared with fruit having similar flesh firmness. The differences in the amount of hemicellulosic polysaccharides between hard and soft fruit were slight. There was no negative correlation between flesh firmness and cellulose content, independent of cultivar and storage period. These data suggest that lower polyuronide content, especially WSP and ASP, in fruit after prolonged storage is one cause of the inferior texture of pears after prolonged storage.

To develop a transformation system for pear cultivars (Pyrus communis L.), we investigated the ability of cotyledon explants produced from seeds of mature fruit to regenerate, and monitored transgene expression during the early stages of the transformation procedure. The greatest shoot regeneration was induced on MS medium, supplemented with 2μM NAA and 30μM TDZ for ‘La France’ cotyledons (40%), and supplemented with 8μM NAA and 30μM TDZ for ‘Bartlett’ cotyledons (75%). Of the three cytokinins (TDZ, BA and Zeatin) examined, TDZ was the most effective for adventitious bud formation. To investigate the transfer of genes into pear cotyledon explants, we used a modified GUS gene that is expressed in plant tissues exclusively. Gene transfer was measured via transient expression of the GUS gene. The greatest frequency of gene transfer (82.7%) occurred when the explants were co-cultivated in the dark for 7 days after being inoculated with Agrobacterium tumefaciens strain EHA101 without pre-culture. A practical transformation was also conducted, in which carnation cDNA encoding an ACC oxidase (DC-ACO) was induced into cotyledon explants of two pear cultivars. Four transgenic ‘Bartlett’ seedlings and two ‘La France’ seedlings were obtained. Simultaneously, three lines of nontransformed control plant that had the same genome as the transgenic plants were obtained by inducing regeneration of a noninoculated cotyledon derived from the same seed as an inoculated cotyledon. PCR and Southern blot analyses confirmed the integration of the transgene in the genomes of all the transgenic lines.

When granulocytes are stimulated under certain clinical conditions, elastase is released therefrom and digests fibrin(ogen) independently of the plasmin system, which may also be mobilized simultaneously. Thus, discrimination of these 2 systems becomes urgent for the diagnosis and treatment of the underlying diseases. Using as immunogen a 97-kd granulocyte-elastase digest of human fibrinogen, we raised an antibody IF-123 that specifically recognizes elastase digests of human fibrin(ogen). The 97-kd elastase fragment resembles plasmic fragment D(1), and the epitope of this antibody is located on the Aalpha (196-204) residue segment. This segment appears to be masked in fibrin(ogen) but exposed when the Aalpha Leu 204-Ile 205 peptide bond is cleaved by elastase. Cathepsin G concomitantly released from granulocytes failed to expose the epitope. By an enzyme immunoassay using IF-123 as the capture antibody, the elastase digests of fibrin(ogen) can be measured in plasma samples without interference by abundantly coexisting fibrinogen. Indeed, we found that the elastase digests were mostly elevated in patients with inflammation or malignant tumors, but remained in a normal range in patients with a benign gastrointestinal tract disease such as duodenal ulcer and polyps in the gallbladder or the colon. Like the plasmic D-dimer, the elastase digests predominantly consisted of the DD/E complex and DD/E-containing high-molecular weight derivatives apparently corresponding to the phase-3 plasmic digests of cross-linked fibrin. (Blood. 2000;95:1721-1728)

'Takasago (Rockport Bigarreau)', one of the major early ripening cultivars of sweet cherry in Japan, was reported to be cross-incompatible with 'Hinode (Early Purple)'. Thus, they were assumed to have the same S-alleles, although their S-genotypes were unknown. However, when 'Takasago' was cross-pollinated with 'Hinode' at the Yamagata Prefectural Horticultural Experiment Station, the fruit set normally (unpublished data), which suggests that they are cross-compatible. In this study, we re-evaluated crossability between the two cultivars by controlled pollination tests and determined their S-genotypes by the molecular typing system recently developed for S-alleles of sweet cherry. The cross-pollination tests conducted at two different locations in Japan showed that 'Takasago' and 'Hinode' were self-incompatible but reciprocally cross-compatible. Furthermore, 2D-PAGE (two dimentional-polyacrylamide gel electrophoresis) analysis for stylar extracts revealed that they have none of the common S-RNases, S-gene products in styles of sweet cherry, which suggests that their S-genotypes are completely different. By S-RNase spot patterns in 2D-PAGE profiles and RFLP (restriction fragment length polymorphism) analysis, S-genotypes of 'Takasago' and 'Hinode' were proposed to be S1S6 and S2Sx(Sx is a novel S-allele different from S1 to S6), respectively. This implies that 'Hinode' is cross-compatible with all cultivars of known S-genotypes. The usefulness of biochemical and molecular methods for S-allele typing employed in this study is discussed.