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Plant diets of 2 sympatric species of wood mice in Japan (Apodemus argenteus and A. speciosus) were determined by DNA meta-barcoding analyses of feces using the nucleotide sequences of the chloroplast trnL P6 loop intron region as a molecular marker. The 2 species showed a relatively large degree of niche overlap in plant dietary profiles, feeding mostly on acorn-producing Fagaceae species (assumed to be Quercus crispula). However, A. argenteus was less dependent on Fagaceae species than A. speciosus. Instead, A. argenteus had a wider niche breadth, feeding upon a wider range of plant families such as Betulaceae, Fabaceae, Oleaceae, Pinaceae, Rutaceae, Sapindaceae, Tiliaceae, and Ulmaceae, which were consumed only infrequently by A. speciosus. There was also evidence for species differences in diet across seasons. Oleaceae species (assumed to be Fraxinus mandshurica) were consumed by A. argenteus from June to August, and by A. speciosus from August to October. The results suggested that A. argenteus is a generalist feeder, and A. speciosus a specialist, and the 2 Apodemus species separate their dietary niches not only by the component plant species overall, but also by differences within seasons.

Knowledge of long-term spatiotemporal effects of disturbances on forest structure, tree regeneration and species composition is key for understanding forest dynamics and predicting future forest responses to climate change. Here, we explore the spatiotemporal impact of disturbances of different severities on tree recruitment and diversity in species-rich oak-fir-maple forest in Hokkaido, a typhoon-prone area in northern Japan, over the past 230 years. The forest disturbance history was reconstructed by growth-release analysis from more than 45,500 tree rings of 385 trees belonging to 15 species. A mixed severity disturbance regime was prevalent over the study period. Altogether, 310 major and 293 moderate growth releases were identified. These were both temporally and spatially localized, with 80% of events detected in only four time periods: 1775–1784, 1815–1839, 1880–1909 and 1950–1979. Disturbances were followed by major recruitment pulses, each lasting around 30 years. Dendrochronological reconstructions alone indicate that severe (i.e. high proportion of releases), infrequent disturbances control tree regeneration and forest development (from oak-dominated forests to mixed-stand with higher proportion of shade-tolerant tree species). However, a combination of temporal and spatial pattern analysis revealed that less severe disturbances, creating small gaps, promote higher density and diversity of recruitment (altogether 19 tree species recorded) compared with severe disturbances. The latter create large forest gaps which became overgrown by dwarf bamboo and suppress tree regeneration. These results provide evidence that severe disturbances interacting with a strong biotic understory filter (as dwarf bamboo), can disrupt forest ecosystem dynamics by significantly reducing the extent and diversity of tree recruitment. Our findings are important as most climate models predict an elevated intensity of typhoons in Northeast Asia. We conclude that a combination of temporal and spatial analyses, as presented here, is necessary to disentangle the complex drivers of long-term forest dynamics.

The increase in light availability resulting from canopy changes or opening is not always beneficial and can inhibit photosynthesis of tree seedlings already under other environmental stress. Tree seedlings' responses to compounded abiotic stress depend on their life-history traits, and understanding the variations of such responses is important for understanding population dynamics under a changing climate. In this study we investigate how the photosynthesis of juveniles of two canopy tree species with different life-history traits, Abies sachalinensis and Betula ermanii, differs in two contrasting sites at a sub-boreal forest in northern Japan—one under a deciduous canopy (Closed site) and the other at a wide canopy opening (Open site). Seedlings at the Open site had low Fv/Fm (quantum yield of photosystem II) for a longer period than those at the Closed site. Abies sachalinensis at the Closed site showed lower Fv/Fm in spring than those at the Open site, but recovered after the canopy's new leaves flushed, indicating its acclimation to the shaded condition. Mean Pmax (light-saturated photosynthetic rate at ambient CO2 levels) of A. sachalinensis seedlings was affected by site and air temperature, while B. ermanii seedlings were also affected by precipitation. Only B. ermanii's seedlings presented growth in the period studied, in spite of observed mid-day drops to Fv/Fm attributed to water-deficit-related photoprotection. Results suggest that the climate change predicted for the Hokkaido area may increase the competitive advantage of broad-leaved deciduous species, such as B. ermanii, in relation to evergreen conifers like A. sachalinensis.

Primary pulmonary vein stenosis (PVS) is rare within the pediatric population and its pathophysiology remains unclear, especially as to how the histopathology relates to its refractoriness to treatment. We report the case of a 4-month-old girl with primary PVS. The lesion in this patient was characterized by fatal obstruction of intraparenchymal small pulmonary veins, associated with localized stenosis at the four pulmonary veno-atrial junctions. All four localized stenoses underwent transcatheter stent implantation. Although the procedure was technically successful, her clinical status failed to improve, and she died 2 months after stenting. Histopathological examination of lung specimens showed severe luminal obstruction by marked intimal proliferation with fibrosis in the intraparenchymal small pulmonary veins, and these findings were present in every lobe. To the best of our knowledge, the histopathological findings and clinical course in this case, including the response to treatments, are extremely rare. We suggest that the histological findings of the small pulmonary veins are important in deciding the indication and appropriate timing of intervention. Learning objective: The outcome of primary pulmonary vein stenosis has remained poor despite aggressive treatment, while the indication and appropriate timing of intervention has not been clarified. The histological findings of small pulmonary veins are important to predict the response to treatment and outcome, and early intervention might prevent the secondary progression of this disease.>

Pompe disease is an autosomal recessive, lysosomal glycogen storage disease caused by acid α-glucosidase deficiency. Infantile-onset Pompe disease (IOPD) is the most severe form and is characterized by cardiomyopathy, respiratory distress, hepatomegaly, and skeletal muscle weakness. Untreated, IOPD generally results in death within the first year of life. Enzyme replacement therapy (ERT) with recombinant human acid alpha glucosidase (rhGAA) has been shown to markedly improve the life expectancy of patients with IOPD. However, the efficacy of ERT in patients with IOPD is affected by the presence of symptoms and cross-reactive immunologic material (CRIM) status. We have treated two siblings with IOPD with ERT at different ages: the first was symptomatic and the second was asymptomatic. The female proband (Patient 1) was diagnosed with IOPD and initiated ERT at 4 months of age. Her younger sister (Patient 2) was diagnosed with IOPD at 10 days of age and initiated ERT at Day 12. Patient 1, now 6 years old, is alive but bedridden, and requires 24-hour invasive ventilation due to gradually progressive muscle weakness. In Patient 2, typical symptoms of IOPD, including cardiac failure, respiratory distress, progressive muscle weakness, hepatomegaly and myopathic facial features were largely absent during the first 12 months of ERT. Her cardiac function and mobility were well-maintained for the first 3 years, and she had normal motor development. However, she developed progressive hearing impairment and muscle weakness after 3 years of ERT. Both siblings have had low anti-rhGAA immunoglobulin G (IgG) antibody titers during ERT and have tolerated the treatment well. These results suggest that initiation of ERT during the pre-symptomatic period can prevent and/or attenuate the progression of IOPD, including cardiomyopathy, respiratory distress, and muscle weakness for first several years of ERT. However, to improve the long-term efficacy of ERT for IOPD, new strategies for ERT for IOPD, e.g. modifying the enzyme to enhance uptake into skeletal muscle and/or to cross the blood brain barrier (BBB), will be required.

Abies sachalinensis and Picea glehnii are co-dominant tree species and major components of the forests of Hokkaido, Japan. Recent work suggests that a reversal in potential competitive superiority at different developmental stages could be important to explain their coexistence. Such shifts in competitive advantage can be mechanistically understood by studying the corresponding physiological differences between distinct life stages. Accordingly, our objective was to investigate in the field the photosynthesis of shade-growing juveniles of these species from two different size-classes, seedlings and saplings. Our results show that seedlings of both species had higher concentrations of photoprotective xanthophylls than saplings, especially in spring, and suggest that seedlings have a lower threshold of stress tolerance than saplings. Photosynthetic capacity per needle area and lateral shoot extension rate decreased from the seedling to the sapling stage in A. sachalinensis, while in P. glehnii, both increased from the seedling to the sapling stage. Abies sachalinensis had higher photosynthetic rates at the seedling stage but lower rates at the sapling stage than P. glehnii. Nevertheless, A. sachalinensis had a higher lateral shoot extension rate than P. glehnii at both stages. Our physiological results support previous ecological observations that A. sachalinensis is a superior competitor to P. glehnii in the understory, and show that its competitive advantage is higher at the seedling stage than at the sapling stage.

Windthrow is recognized as an extremely significant disturbance in many forests. Its effects are increased by stand fragmentation, which exposes the stand to strong winds. In this study, we investigated the change in tree mortality in fragmented stands with the distance from the stand edge, in a conifer–broadleaved mixed forest in northern Japan. We set out experimental plots having three stand sizes (400, 1,600, 6,400 m2) and examined the stand dynamics over 10 years. Tree mortality tended to be higher in smaller stands, although an effect of stand size was found only in the first 5 years of the study. Distance-dependent individual mortality was obvious in Abies sachalinensis, the most vulnerable major tree species, again in the first 5 years, suggesting that wind-risk management should emphasize the area within ca. 20 m from the stand edge. No distant-dependent effect was found, however, in the latter 5 years, in which there was a strong typhoon; tree deaths occurred throughout the stand (irrespective of distance within) as a result of this event. We conclude that the severity of wind can cause the features of wind-induced damage to differ; stand edge effects peculiar to a small forest are unlikely to occur with particularly strong winds, and the effect of fragmentation might therefore be clear only in weaker disturbances.

The present paper shows simulated results of seasonal and inter-annual variations in energy and carbon exchanges and forest dynamics in a sub-boreal deciduous forest using a fully coupled atmosphere–vegetation interaction model [multilayered integrated numerical model of surface physics-growing plants interaction (MINoSGI)]. With careful adjustment of site-specific eco-physiological parameters, MINoSGI reproduced successfully stand biomass–tree density relationship based on the forest inventory data for 7 years (1999–2005) and seasonal and inter-annual variations in energy and CO2 fluxes measured by means of eddy covariance technique for 3 years (2003–2005) in the sub-boreal forest, northern Japan. In addition, MINoSGI estimated annual evapotranspiration (E vt) at 328.6 ± 25.8 mm year−1, net primary production (NPP) at 372.1 ± 31.5 gC m−2 year−1 and net ecosystem exchange (NEE) at −224.2 ± 32.2 gC m−2 year−1. We found the estimate of annual NEE in our site lies among the estimates at other forest stands with the almost same climatic conditions in northern Japan, although the tree species and stand age of these forests are different from those of our site. Overall, MINoSGI was found useful to present simultaneous simulations of forest dynamics, surface energy, and carbon exchanges of a forest stand in the future from micro-meteorological and ecophysiological points of view.

The relationship between rain flow into the soil and forest structure was investigated in a dense deciduous Betula ermanii forest in northern Japan. The forest floor was covered with dwarf bamboo Sasa kurilensis. Observation was conducted from mid-July to late October in 1998. Leaf fall of Betula started in early September and ended in late October. Stemflow was proportional to rainfall and tree size [diameter at breast height (DBH)], and for the same rainfall, stemflow increased with leaf fall. On the contrary, throughfall decreased with leaf fall. Throughfall was intercepted also by Sasa in proportion to its leaf area. Multiple linear regression analysis revealed that stemflow and throughfall of Betula and Sasa were predictable as functions of rainfall and forest structural characteristics, such as DBH, tree density, and stand leaf mass. The rain interception by plants tended to decrease from summer to autumn, but the difference in the interception was about 2% between July (fully expanded leaves) and late October (lack of leaves). About 96 and 87% of rainfall reached the above- and below-Sasa layers, respectively. Thus, this study showed that understory Sasa is a major component of rain interception within the stand and that rain flow into the soil can be estimated by using rainfall and the forest structural parameters, such as DBH, tree density and stand leaf mass.

Summary Background Transcatheter occlusion of infantile patent ductus arteriosus (PDA) challenges the interventionist. Purpose To analyze the risk factors for adverse events from this procedure in patients younger than 12 months. Subjects We retrospectively analyzed data on 32 patients younger than 12 months in whom transcatheter coil occlusion of a PDA was attempted. Ages ranged from 1 to 11 (median, 7) months and body weight from 1.2 to 10 (6.0) kg. The minimum ductal diameter ranged from 1.0 to 4.6 (3.3) mm and pulmonary to systemic flow ratio from 0.7 to 12.5 (2.2). Major adverse events were defined as those requiring surgery, while minor adverse events included transient hemolysis not needing treatment, coil migration with successful transcatheter retrieval, and mild left pulmonary artery (PA) stenosis. We determined whether any factors such as age, body weight, minimum PDA diameter, angiographic type, operator, and use of a 0.052-in. Gianturco coil related to the occurrence of adverse events. Results In two patients, coils could not be deployed in the appropriate position. They underwent surgery following transcatheter retrieval of coils. Coils were successfully deployed in the other 30 patients, however, one patient developed persistent hemolysis that required surgical retrieval of the coils and closure. PDA was completely closed in the other 29 patients (clinical success rate, 91%). Thus, there were three major adverse events, while minor adverse events occurred in five patients. Univariate analysis did not identify any single factor that contributed to either major, minor, or total adverse events. However, all major adverse events occurred in patients under 6 months and less than 6 kg body weight with a minimum duct diameter of more than 3.5 mm. Conclusion Transcatheter coil occlusion of PDA is feasible in selected patients younger than 1 year. A minimum diameter more than 3.5 mm in patients under 6 kg may be a risk factor for major adverse events.

In a Japanese forest, CH4 uptake rate and methanotrophic community structure in the soil were investigated at four sites of different vegetation. At two of these sites, undergrowth was dominated by Sasa senanensis, and that of another was dominated by Sasa kurilensis. At the rest site, undergrowth had been removed artificially. The tree-layer composition differed between the two sites with S. senanensis, but tree layer of the other two sites were dominated by the same species. At the site lacking undergrowth, observed CH4 uptake rate was twice as high as that at the other sites. Under laboratory conditions, soil sample from the site lacking undergrowth exhibited CH4 consumption rate higher than that of the adjacent site with the same dominating tree species. The community structures of methanotrophs were investigated with denaturing gradient gel electrophoresis (DGGE) of the gene encoding particulate methane monooxygenase (pmoA). The banding patterns observed were different depending on the type of undergrowth vegetation. The sequences of the DGGE bands were closely related to each other and belonged to the “upland soil cluster alpha” (USCα). These results imply possible close relationship between the undergrowth vegetation and methanotrophic communities in forest soils.

In order to more accurately evaluate the functional activity of forest stands by canopy production and evapotranspiration, we improved the methods for field measurements and statistical modeling to estimate foliage configuration (spatial distribution of leaves) while simultaneously reconstructing the three-dimensional photosynthetically active photon flux density (PPFD) distribution (PPFD pattern) in a forest canopy. By using a sensor (photodiode) array, a PPFD pattern was observed in summer 2002 under the canopy in an even-aged, pure stand of Japanese mountain birch Betula ermanii Cham. (17-year-old) in Hokkaido, northern Japan. A Markov Chain Monte Carlo (MCMC) sampling technique is developed such that a set of foliage configurations generated by the model referred to as the Gibbs foliage canopy (GFC) approximates the field-measured PPFD pattern. The posterior distribution of the foliage configurations is generated by the parallel tempering MCMC of eight independent series of foliage configurations. The GFC model generated the posterior distribution of the LAI estimates (mean 4.56) that appeared to be appropriate in comparison to other LAI estimates of the B. ermanii stand based on the indirect and nondestructive methods by LAI-2000 (LAI = 3.43) and litterfall traps (LAI = 5.56) because they could be under- and overestimated, respectively. Our evaluations of the canopy production and evapotranspiration rates suggest that the relationship between LAI and canopy functions was not very simple because it depended on the nonlinear functional forms of the leaf responses of photosynthesis and transpiration to PPFD. The current study demonstrates an application of MCMC techniques that can generate a set of possible structures of unobserved/unobservable objects based on the high resolution data set obtained by some indirect (or remote-sensing) methods.

Mitochondrial acetoacetyl-CoA thiolase (T2) deficiency is an inherited metabolic disorder of isoleucine and ketone body catabolism. We report the cases of two siblings who showed clinically mild forms of this disorder. They did not excrete tiglylglycine in urine. Their EB-transformed lymphocytes contained residual T2 activity, which was confirmed by immunotitration analysis. In immunoblot analysis, the bands corresponding to T2 in the samples of the cell lines from two patients were the most intensely detected among those from 19 T2-deficient cell lines tested.

We investigated how removal of understory dwarf bamboo (Sasa kurilensis Makino et Shibata) affected growth and water use of young Betula ermanii Cham. trees in a secondary forest in northern Japan. We compared current-year shoot morphology, leaf water-relations characteristics, and whole-tree water use of B. ermanii trees growing with dwarf bamboo in the understory (intact plot) to those of trees growing where dwarf bamboo was experimentally removed (removal plot). Current-year shoot length and internode frequency increased, while internode length and individual leaf area decreased in response to dwarf bamboo removal. Carbon isotope composition (δ13C) of leaves did not change indicating that leaf water-use efficiency was unaffected by the presence/absence of dwarf bamboo. Pressure–volume analysis indicated that leaves in the removal plot had lower water uptake ability. During mid-summer, trees in the removal plot sustained high sap flow velocity after peaking at midday, while that of trees in the intact plot declined. In addition, whole-tree sap flux and soil-to-leaf hydraulic conductance were both higher for trees in the removal plot. We inferred that the observed changes reflect hydraulic homeostasis of B. ermanii trees to maintain constant water-use efficiency in response to belowground competition with dwarf bamboo. Removal of dwarf bamboo is, therefore, an effective silvicultural prescription to enhance growth of overstory trees by relieving belowground competition for soil water.

We analysed the effects of Quercus crispula acorn abundance on the density dependence of the large Japanese wood mouse Apodemus speciosus using time series data (1992–2007). The data were obtained in a forest in northern Hokkaido, Japan, by live-trapping rodents and directly counting acorns on the ground. Acorn abundance in one year clearly influenced the abundance of wood mice in the following year in all models examined based on the Gompertz and Ricker model; in addition, the abundance of wood mice had effects on the population. Acorn abundance influenced the strength of density dependence (intraspecific competition) of the wood mouse population. When the abundance of acorns was high, density dependence was relaxed, and as a result the equilibrium density at which the population growth rate decreased to zero became higher. Those effects of acorn abundance were regarded as a nonlinear perturbation effect (sensu Royama 1992). The nonlinearity of density dependence was also detected; higher densities had stronger effects on population growth rates.

We analyzed effects of seed-hoarding by rodents on the variation in seed mass and seed success for a perennial forest undergrowth plant — Symplocarpus renifolius Schott ex Miquel — in Hokkaido, northern Japan. Although density of rodents differed greatly between seasons, more rodents were always captured in mesic Sasa sp. patches with dense foliage than in wet Lysichiton sp. patches. In the season with fewer rodents, they cached seeds close to the original places irrespective of vegetation, while in the season with abundant rodents, they transported seeds further and cached seeds disproportionately in Lysichiton patches. Seeds missed by rodents were larger than seeds that were eaten or that survived. Sasa patches are more suitable for seedlings to establish and a size advantage was observed there, but even small seeds could establish in Lysichiton patches, although seedling success was lower. We concluded that maternal plants of Symplocarpus renifolius increase their reproductive success by having small to middle-sized seeds transported to suitable sites while offering larger seeds as rewards to the transporters. Since the variation in seed mass was not correlated with the biomass per seed of the maternal plant, the large variation in seed mass is considered to have evolved through the density-dependent hoarding by rodents.

The effects of the abundance of acorns of the oak, Quercus crispula, on the population dynamics of three rodent species (Apodemus speciosus, A. argenteus, and Clethrionomys rufocanus) were analyzed using time series data (1992–2006). The data were obtained in a forest in northern Hokkaido, Japan, by live trapping rodents and directly counting acorns on the ground. Apodemus speciosus generally increased in abundance following acorn masting. However, the clear effect of acorn abundance was not detected for the other two rodent species. Acorns of Q. crispula contain tannins, which potentially have detrimental effects on herbivores. Apodemus speciosus may reduce the damage caused by acorn tannins with tannin-binding salivary proteins and tannase-producing bacteria, whereas such physiological tolerance to tannins is not known in the other two rodent species. The differences in the effects of acorns between the three species may be due to differences in their physiological tolerance to tannins.

Phytolith analysis was applied to clarify a vegetation history at Picea glehnii stands on the Dorokawa Mire, northern Hokkaido. Phytolith assemblages from surface samples and Holocene deposits from the mire are used to clarify the stand-scale vegetation history, with special focus on the dynamics of Gramineae, which includes dwarf bamboo, and the establishment of P. glehnii stands on the mire. The phytolith records during the early-Holocene (ca. 12,000 to 10,000 cal BP) indicate the distribution of Pooideae-dominated vegetation, which reflects the cool climate. Phragmites (reed) dominated vegetation from the early to mid-Holocene (ca. 10,000 to 5,000 cal BP) suggests wet conditions like low-moor. The reed was replaced by dwarf bamboo at ca. 5,000 cal BP, although the distribution of dwarf bamboo was scattered. At ca. 1,500 cal BP, dwarf bamboo increased abruptly and has been sustained to the present. Also, Pinaceae type phytoliths began to occur continuously at ca. 1,000 cal BP. Taking into account the relationship between modern vegetation and modern phytolith assemblages on the mire, the occurrence of the Pinaceae type phytoliths from the sediment samples indicates the existence of P. glehnii in the study sites. On the basis of these results, P. glehnii stands with dense undergrowth of dwarf bamboo would have been established in the study sites on the mire by ca. 1,000 cal BP at least.

In many Japanese forests, the forest understory is largely dominated by dwarf bamboo (Sasa) species, which compete with overstory vegetation for soil nutrients. We studied the rate of leaf litterfall, and decomposition and mineralization of carbon (C) and nitrogen (N) from various components (leaf, root, wood, and rhizome) of overstory and understory vegetation in a young Betula ermanii forest from 2002 to 2004. Total litterfall was 377 g m−2 year−1, of which the overstory vegetation contributed about two thirds. A litter decomposition experiment conducted for 770 days indicated that mass loss of different litter components varied significantly, except for Sasa kurilensis wood and rhizome. Relative decomposition rates were significantly greater in the first growth period (June to October) than the dormant period (November to May) in most cases. Rainfall was the most important abiotic variable, explaining 75–80% of the variability in mass loss rates. Concentrations of ethanol soluble substances and N were significantly positively correlated (r=0.77 to 0.97, P

We investigated the changes in soil microbial biomass C (MBC), microbial biomass N (MBN) and N mineralization in Sasa kurilensis-present (SP) and S. kurilensis-removed (SR) stands in a Betula ermanii forest. The mean levels of MBC and MBN were significantly higher in the SR stand than in the SP, which may have positively influenced the N-mineralization rate as depicted by a significant positive correlation between these variables and the N-mineralization rate. N immobilization and subsequent N release along with decreased use of available soil N due to S. kurilensis removal may have ensured greater N availability in the SR stand.

Dwarf bamboos (mainly Sasa species) form dense undergrowth in many forests in Japan and compete with overstory vegetation for soil resources. For a better understanding of the interaction between tree and undergrowth root for soil nutrients, we compared soil N availability, root biomass and its substrate quality in two Betula ermanii stands. In one stand, the aboveground part of undergrowth (Sasa kurilensis) had been removed for 5 years (SR) and in the other, the undergrowth was present (SP). The SR stand had significantly higher NO3-N levels in soil (1.7–5.5 mg kg−1 at different soil depths) than the SP stand (1.2–1.7 mg kg−1), which may affect the amount and substrate quality of fine root. Although the total (live + dead) of the root and rhizome (root–rh) mass did not differ between the two stands, the total production by these categories was about half in the SR stand than the SP stand. Further, the proportion of dead root–rh mass was about two times in the SR stand than the SP stand. In the investigated depth (to 30 cm), the contribution of the C and N inputs to the total in the uppermost layer (0–10 cm deep) was greater in the SR stand (56–59%) than the SP stand (38–42%). Total root–rh of S. kurilensis in the SP stand contributed to about 38–40% of the total C and N input, and in the SR stand the contribution was still about half that of the SP stand. Further, the acid-insoluble C:N ratio in very fine root and live fine root of B. ermanii was significantly less in the SR stand. The contribution of N content in very fine root to the total root–rh was much greater in the SR (45%) stand than the SP stand (36%). These results suggest that the remaining S. kurilensis detritus and the decreased N use by this species after its removal resulted in increased N availability for B. ermanii. Natural regeneration of tree species after simultaneous death of Sasa species, which is very common in Sasa-dominant forests in Japan, may in part, be facilitated by the presence of residues of the root–rh of Sasa species.

Objective To investigate whether reduced levels of plasma platelet-activating factor acetylhydrolase (PAF-AH) as a result of a genetic polymorphism are involved in the pathogenesis of Kawasaki disease (KD). Study design The frequency of a V279F polymorphism (G/T transversion) in the PAF-AH gene was quantified in 76 Japanese children with KD and 112 healthy Japanese adults using the allele-specific polymerase chain reaction (PCR). Associations between genotype, clinical features, and resistance to intravenous immunoglobulin (IVIG) were investigated in the patients with KD. Plasma PAF-AH activity was measured by using [3H]-acetyl-PAF. Results There were no significant differences in genotype frequency between patients and controls (P = .51). Compared with the GG (normal genotype) group, significantly more patients in the GT (heterozygous) +TT (homozygous deficient) group required additional IVIG (52% vs 14%, P = .001). The duration of fever and maximum serum C-reactive protein (CRP) levels also were significantly increased in the GT+TT group (P = .012 and .036, respectively), whereas plasma PAF-AH activity was significantly lower (P Conclusion We conclude that the V279F polymorphism in the plasma PAF-AH gene and consequent enzymatic deficiency is one of the factors for IVIG nonresponse in Japanese patients with acute KD.

� Background and Aims Serpentine soils are characterized by the presence of heavy metals (Ni and Cr) and excess Mg; these elements often suppress plant growth. Picea glehnii is nevertheless distributed widely on serpentine soils in northern Japan. Growth characteristics were compared among P. glehnii, Picea jezoensis (distributed in the same region) and Picea abies (planted for timber production), and concentrations of elements in various tissues over time and the amount of ectomycorrhizal infection in short roots were evaluated. � Methods Seedlings of three spruce species were planted in two types of experimental plots, comprising serpentine soil and brown forest (non-serpentine) soil, and these seedlings were grown for 3 years. Growth, ectomycorrhizal infection of short roots, and elemental composition of tissues were examined. � Key Results The total dry mass of P. glehnii planted on serpentine soil was almost the same as on brown forest soil, and a large number of needles survived to reach later age classes. By contrast, growth of P. jezoensis and P. abies in serpentine soil was significantly less than in brown forest soil, and needle shedding was accelerated. Moreover, roots of seedlings of P. glehnii on serpentine soil were highly infected with ectomycorrhiza, and the concentration of Ni in needles and roots of P. glehnii was the lowest of the three species. � Conclusions Picea glehnii has a high ability to maintain a low concentration of Ni, and the ectomycorrhizal infection may have the positive effect of excluding Ni. As a result, P. glehnii is more tolerant than the other spruce species to serpentine soil conditions. a 2005 Annals of Botany Company

Oxygen and carbon isotopic ratios (δ18O and δ13C) were analyzed for cellulose extracted from tree rings of 5 oak trees (Quercus crispula) and 4 fir trees (Abies sachalinensis) standing in a 1 ha plot of a sub-boreal conifer-hardwood mixed forest, northern Japan. The δ18O variations were well correlated between individual trees of Q. crispula (canopy trees) and A. sachalinensis (recently grown-up sub-canopy trees), although A. sachalinensis had about 1 ‰ higher δ18O values than Q. crispula on average and there was an apparent one-year phase lag between δ18O variations of the two species. The similar inter-annual variation in δ18O among different individuals and species suggests a common environmental control. Contrary to δ18O, the inter-annual variations in δ13C did not possess any common trends among individual trees for either Q. crispula or A. sachalinesis, suggesting that the ecological effects, such as spatial heterogeneities in δ13C and/or concentration of CO2 in canopy air and/or competition for light with neighboring trees, regulate the δ13C of photosynthetic products in each tree. Seasonal variations of the δ18O and δ13C within annual tree rings of Q. crispula showed random and cyclic characteristics, respectively. The difference between the annual patterns of δ18O and δ13C supports the idea that δ18O is controlled by some environmental factors, which change from year to year, but δ13C is primarily governed by physiological conditions of the tree itself, which repeat regularly in every growing season. The historical variation in δ18O of tree-ring cellulose in Q. crispula has negative correlations with those in both of winter and summer precipitation amounts, whereas it does not show any relationship with temperature, probably due to multiple source areas of water vapor for the precipitation at the studied area. Because the δ18O of precipitation in northern Japan is positively correlated with air temperature, the correlation between δ18O and winter precipitation suggests that, in a year of heavy snowfall, the soil in this forest retains larger amount of lower δ18O water derived from snowmelt, which is taken by roots of Q. crispula in summer. On the other hand, the negative correlation with summer precipitation cannot be elucidated by the δ18O of rainfall, but must be explained by a higher relative humidity in the growing season in a year of larger summer rainfall. Our results confirm the potential of δ18O of tree-ring cellulose to reconstruct past climate in a forest with a heavy snowfall, and suggest the importance of the hydrological knowledge in an atmosphere-soil-plant system for the utilization of tree-ring δ18O in paleoenvironmental purposes.

Despite intravenous immunoglobulin therapy, a certain percentage of patients with Kawasaki disease (KD) still develop coronary arterial lesions (CAL). In an effort to find new combined therapies to reduce the incidence of CAL, we focused on the oedema which can be an important sign of the increased vascular permeability in KD. A total of 127 patients with KD were included in the retrospective study. Serial weekly changes in serum sodium and albumin levels from the 1st to the 4th week of illness were examined. In addition, the maximum rate of increase in body weight from admission to the 14th day of illness was evaluated. Serum sodium levels (mEq/l) in only the 2nd week of illness were significantly lower in patients with CAL than in those without CAL (mean ± SD, 135.5±4.5 versus 138.0±2.4, P

Article, FOREST ECOLOGY AND MANAGEMENT. 174(1-3):39-50(2003)

Vascular anomalies due to occlusion or thrombosis of the inferior vena cava (IVC) may be hazardous to renal transplantation, and preoperative vascular evaluation is important for safe and successful surgery. The purpose of this study was to assess the utility and accuracy of two-dimensional time-of-flight (2D-TOF) magnetic resonance venography (MRV) as an alternative to conventional angiography for evaluating the IVC and iliac vein in potential pediatric renal transplant recipients. Four children with chronic renal failure were evaluated with 2D-TOF MRV by superior presaturation pulse and target maximum intensity projection. The whole MRV examination and filming required less than 30 min. All four patients had a normal IVC and iliac vein. Two of the patients underwent renal transplantation, and the MRV findings were in total agreement with the final anatomy revealed intraoperatively. MRV is accurate for evaluating the condition of the IVC and iliac vein. It is a reliable, noninvasive and rapid technique that can be considered as an alternative to invasive angiography for evaluation of children scheduled for transplantation. We recommend the use of this noninvasive procedure to ascertain the patency of the IVC in all infants and children with a history of indwelling catheters in the IVC or those with a propensity to thrombosis, i.e., all recipients with nephrotic syndrome. The insertion of catheters in the femoral vein in children who may become candidates for renal transplantation should be discouraged.

Summary 1 The gradient relations proposed by Wheeler & Proctor for NW European mires were tested for six Carex species common in north Japanese mires. Hydrochemical properties of their preferred habitats were compared with above-ground biomass data. 2 Canonical discriminant analysis showed that soil water pH was the strongest discriminant between habitats of the Carex species, with total dissolved nitrogen (TDN) concentration also contributing, independently of pH. 3 Two major patterns were apparent in the distribution of Carex species: pH determines a bimodal distribution into fens with pH > 5.0 and bogs with pH

Summary 1Theory suggests that there should be a trade-off between nitrogen productivity (A) and mean residence time of nitrogen in plant tissues (MRT), and that this trade-off depends on the N availability of the habitats. To test this, we studied A, MRT and nitrogen-use efficiency (NUE, reciprocal of N concentration in the dead shoot) in wetland Carex species sampled from seven lowland mires in Japan. 2The NUE and MRT of unproductive species that usually grow in acidic and N-poor habitats exceeded those of productive species that are abundant in weakly acidic and N-rich habitats. Except for the most productive species, C. lyngbyei, interspecific differences in A were small, irrespective of productivity. 3Intraspecific variation in A was relatively large in contrast to those in NUE and MRT. Within each species, no parameter correlated with the concentration of total dissolved nitrogen (TDN) in the soil water. 4 Although NUE and MRT of the plants growing in the weakly acidic habitats correlated negatively with TDN, they were constantly high in the acidic habitats regardless of the TDN concentration. Responses of A did not correlate with TDN concentration of soil water in either acidic or weakly acidic habitats. 5 A trade-off between A and MRT in the five Carex species was not detected in relation to habitat N richness. We suggest that soil water acidity dominates the ecological performance of the Carex species, and that the trade-off between A and MRT does not necessarily apply to wetland vegetation.

Spatial patterns of the oxidation–reduction potential (Eh) of soil, water level and chemistry were examined in the fen area of the Tohfutsu mire, northern Japan, where horse pasturage has been carried out throughout the growing season every year. The fen vegetation consisted mosaically of communities mono- or codominated by Eleocharis kamtschatica, Iris setosa and Carex lyngbyei. The highest concentration of total dissolved nitrogen of soil water was observed in the dwarf community dominated by E. kamtschatica with smaller biomass, whereas the nutrient level was lower in the community monodominated by C. lyngbyei with larger biomass. Principal component analysis denoted well that Eh, N, K, and pH contributed to the differentiation of these communities significantly. During the growing season that was investigated, the highest nitrogen concentration was observed in midsummer, when plants are expected to absorb nutrients intensely, indicating that the supply of dissolved nitrogen far exceeded the nutrient uptake of plants. Multiple habitats with reduced soil were formed by submergence and by an excess of nitrogen due to pasturage, and the soil reduction indirectly inhibited the incursion of species with large biomass at such sites. It was demonstrated that soil Eh contributed to the anomalous pattern of vegetation where the supply of available nitrogen exceeds the uptake by plants.

Regional variation in size and shape of Sphagnum hummocks of eight lowland mires throughout Hokkaido Island, northern Japan, was examined in relation to climatic factors. The size and shape of hummocks significantly differed among the regions: low and flat hummocks occurred in the northern region and next to the Sea of Japan; moderately raised and conical hummocks occurred in the western part of the Pacific coast; and extremely raised and cylindrical hummocks occurred in the eastern region. Multiple regression analysis revealed that the mean and maximum heights and height/basal area of hummocks were negatively correlated with evapotranspiration rate (E0) in summer, duration of sunshine, and air temperature. Of these, evapotranspiration rate in summer positively correlated with radiation and thermal factors. Mean height of hummocks within a mire was increased with precipitation during the growing season. Because the regional difference of the hummock form was not related to the difference in nutrient conditions, the effects of evapotranspiration and precipitation prevailed over edaphic conditions. Higher E0 in summer was considered to cause water stress for hummock species in the northern region and next to the Sea of Japan, whereas heavy rainfall relieved it in the western region of the Pacific coast. Consequently, lower and flat hummocks were a result of the higher E0 in summer, moderately raised and conical hummocks of the medium E0 and high precipitation, and extremely raised and cylindrical hummocks of a lower E0 due to prolonged foggy days.Key words: evapotranspiration, duration of sunshine, minerotrophy, ombrotrophy, precipitation.

The Research Committee of Ministry of Health, Labour and Welfare 'Study of treatment and long-term management in Kawasaki disease' reported the guidelines for catheter intervention in coronary artery lesion in Kawasaki disease in this paper. The contents include: (i) background and natural history of coronary artery lesion in Kawasaki disease; (ii) indication of catheter intervention; (iii) types of procedure, and their indication and care; (iv) institute and backup system; (v) the management after procedure, evaluation and follow up; and (vi) prospects, especially in relation to bypass surgery.

The authors evaluated partial anomalous pulmonary venous return by magnetic resonance (MR) images. Seven patients with this congenital anomaly underwent MR imaging examination. Conventional spin-echo and gradient-echo imaging were performed. In addition, during acquisi tion of gradient-echo images, saturation pulses were imposed on the affected lung. Spin-echo images showed the anatomical situation of the anomalous veins, and gradient-echo images revealed the blood flow in the veins. With saturation technique, the direction and drainage of blood flow in the anomalous veins were well defined. The study suggests that MR imaging with spin-echo method and gradient-echo method with or without saturation pulses is a useful and noninvasive method of diagnosing partial anomalous pulmonary venous return. MR images with spin- and gradient-echo methods were useful in defining the anatomical situation and blood flow in the anomalous veins. By imposing saturation pulses on the affected lung field, the direction and drainage of blood flow in the anomalous veins were clearly demonstrated.

Background: The aim of the present study was to investigate whether neutrophils are early effector cells for vascular endothelial damage in the acute phase of Kawasaki disease (KD) by examining serial changes in neutrophil counts and serum levels of neutrophil activation cytokines, such as granulocyte colony stimulating factor (G-CSF) and interleukin (IL)-8. Methods: From October 1994 to June 1998, a total of 52 patients with KD were included in the study. Thirty-three patients had some infectious diseases, while 20 healthy children served as control subjects. Serial changes in neutrophils were counted by the optimal Wright–Giemsa staining method and serum levels of IL-8 and G-CSF in patients with KD were measured by an enzyme-linked immunosorbent assay system. Results: Serum G-CSF levels both before and after intravenous immunoglobulin therapy (IVIG; P

The relationship between water chemistry and vegetation was studied in a coastal ombrotrophic mire in northern Hokkaido, Japan. The distributions of Sphagnum and Phragmites communities were separated clearly by the pH and ion concentration of the peat surface-pore water. The drainage ditches along the road across the center of the mire had a high pH and ion concentration, as did the peat water in the western part of the mire. It was found that fields used for livestock farming on a hill to the west of the mire leached materials into the mire through drainage ditches, surface runoff, and probably also through ground water, and thus influenced the water chemistry of the mire. Management of the water, including that in the catchment of the mire, should be introduced before biological buffering capacity against excess nutrient loading caused by human activity is exceeded and the mire loses its ombrotrophic status.

Our objective was to show the presence of nitric oxide synthase (NOS) in the mammary glands of lactating rats and to determine the role that nitric oxide plays in lactation of humans. We used the nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase reaction and immunostaining on fresh frozen breast tissue obtained from lactating Wistar rats (13-18 wk old, 320-380 g, 3-4 d after parturition, first pregnancy). The breast tissues positive for NADPH diaphorase staining were the mammary gland, muscle, sebaceous gland, epidermis, and endothelium of the lactiferous ducts and blood vessels. These findings corresponded to tissues that were NOS-immunoreactive. The NOS detected in the mammary glands was the constitutive NOS. The finding of positive anti-NOS immunoreactivity and of positive NADPH diaphorase activity in the cells of the rat mammary glands leads us to conclude that nitric oxide is synthesized in mammary glands of rats. The high nitric oxide activity in the human breast was previously reported by measuring the total concentration of nitrite plus nitrate, biopterin, and neopterin in human milk. These results suggest that nitric oxide plays a role in the secretion of human breast milk.

One-month-old boy with double outlet right ventricle and pulmonary atresia was referred to us for surgical treatment. As he had a membranous obstruction of the pulmonary artery we chose closed Brock operation as an initial procedure. A 6.5 mm in diameter of Trocar was used to open the atretic valve. Postoperative course was uneventful and his oxygen saturation was maintained satisfactory. At the age of one year and nine months he underwent corrective surgery. The pulmonary valve was widely opened enough to perform the right ventricular outflow tract reconstruction with valvotomy and outflow patch. The boy got well and was followed in the outpatient clinic. Double outlet right ventricle with membranous pulmonary atresia is a rare combination and closed Brock operation is shown to be one of the most effective procedure for this type of anomaly.

Background . Many surgeons recommend early repair of doubly committed subarterial ventricular septal defect regardless of the clinical symptoms. We reviewed our patients of this anomaly with aortic cusp prolapse to justify this strategy. Methods . We reviewed the preoperative and postoperative records of 27 patients with doubly committed subarterial ventricular septal defect and aortic cusp prolapse. The patients' ages ranged from 2 months to 11 years (median, 4.6 years). Results . During the preoperative observation period, aortic regurgitation (AR) developed in 65% of the patients. In the 8 patients without AR before the operation, AR did not develop after the operation, whereas AR persisted in 12 (63%) of the 19 patients with preoperative AR. To identify the risk factors for persistent AR after the operation we analyzed the data for the patients with preoperative AR in the persistent AR group (n = 12) and eliminated AR group (n = 7) and found a longer period from the onset of AR to the operation in the persistent AR group (32.1 ± 10.1 versus 5.6 ± 1.9 months; p = 0.014). During the follow-up period 10 of the 17 patients with mild AR before the operation showed persistent AR in the postoperative period, but it did not progress. Conclusions . We conclude that early surgical repair with a minimum observation period is essential for prevention of residual AR. Even if a tiny AR is detected preoperatively, the patient should be surgically treated immediately.

A case of tetralogy of Fallot associated with anomalous origin of the right pulmonary artery from the ascending aorta and hypoplastic left pulmonary artery was successfully repaired. Following the simultaneous procedure with banding of the right pulmonary artery and replacement of modified Blalock-Taussig shunt to the left pulmonary artery at 34 days of age, the intracardiac repair was performed successfully at 1 year and 10 months of age. The patient was well 6 months postoperatively, without unilateral pulmonary hypertension.

Summary In Kawasaki disease patients, increases in excretion of urinary neopterin coincided with fever and monocytosis in peripheral blood. We examined the products of neopterin, tumor necrosis factor-α (TNFα) and Interleukin-1 β (1L-1β) from healthy adult macrophages/monocytes (Mφ>/M), after stimulation with several activators to obtain some understanding of Kawasaki disease. Upon stimulation with either lipopolysaccharide (LPS) or polyinosinate-polycytidylate (Poly I:C), the Mφ/M released neopterin and pyogenic products (TNF-α or 1L-1β). The release of neopterin was eliminated by the addition of the anti-interferon-y antibody. The production of both TNF-α, 1L-1β and neopterin from Mφ/M upon stimulation of LPS was augmented in a co-culture with low dose recombinant interferon-y (rIFN-γ). Upon stimulation with rIFN-γ alone, however, the Mφ/M released neopterin but not the pyogenic products. A preliminary examination failed to detect. any difference in the response of the Mφ/M in adults annd children after stimulation with LPS. We concluded that some endotoxins could trigger the onset of Kawasaki disease and that endogenous IFN-γ can play an important role in the abnormality of Kawasaki disease patients

Recently, transcatheter device occlusion has become the first choice treatment for adult persistent ductus arteriosus (PDA). However, various complications such as atrial fibrillation requiring anticoagulation, pulmonary hypertension, and ventricular dysfunction may challenge the interventionist. We report a 61-year-old patient with a large PDA complicated by left ventricular dysfunction, atrial fibrillation, and left atrial thrombus. Computed tomography documented the PDA of Krichenko type A with the narrowest diameter of 8mm. We successfully closed the PDA using an Amplatzer duct occluder under anticoagulation with wafarin. His post-operative course was complicated by ventricular tachycardia and deteriorating left ventricular pump function. Although endomyocardial biopsy from the left ventricle showed myocardial hypertrophy and interstitial fibrosis, possibly caused by chronic volume overload, left ventricular pump function improved dramatically with restoration of sinus rhythm during follow-up. Left ventricular dysfunction, even when associated with histological changes, may be nearly normalized by volume unloading in an adult with a large PDA. Learning objective: Transcatheter device occlusion has become the first choice for adult persistent ductus arteriosus (PDA). It is important to note various complications associated with transcatheter occlusion of PDA in adult, such as arrhythmia, pulmonary hypertension, and ventricular dysfunction. Temporally dysfunction of left ventricular (LV) systolic performance usually occurs following PDA closure, because of reduced muscle fiber stretch by the sudden reduction in LV volume overload and increased LV afterload. Although histological remodeling of LV may be caused by volume overload due to significant left-to-right shunt in adults, volume unloading can, not only prevent further deterioration of LV function, but also may also reverse the substrate of arrhythmia.>

Effects of climatic factors on the forest plant distribution were examined in Hokkaido Island, northern Japan, where boreal and temperate plants frequently co-occur, and the relationship of floral make-up with phytogeography and life form was analysed. From the climatic preference of tree species consisting of mixed forest, the co-occurrence of boreal and temperate plants was found over a wider thermal range in regions of little rainfall. However, co-occurrence in a certain forest site was more notable in the understory than in the crown. A particular case of this involves southern evergreen shrubs and herbs in a boreal coniferous forest. Another is the presence of northern summergreen herbs in a temperate hardwood forest. It is speculated that the co-occurrence dates back at least to the late Quaternary, when a decrease in temperature associated with the glacial period forced understory plants to adapt their life form or leaf habit to snowcover and the light conditions of interior forests. Recent geographical evidence suggests that the island has been isolated from the southern island for at least 70000 years. Thus, the postglacial re-expansion of southern species does not appear to be due to immigration but rather due to their expansion from refuges on the island such as Oshima Peninsula for snow-tolerant species and Hidaka District for snow-intolerant species.

Foliar phenologies of forest understory plants were categorized, and the distribution pattern of leaf habit was examined among different forest environments. Various patterns of foliar phenology were found, especially in herbaceous plants. In addition to the seasonal light regime controlled by the phenology of canopy trees, differences in the length of period with snow cover led to the divergence. Perennial-leaved plants predominate in intensely shaded habitats while annual-leaved plants are more abundant in less shaded habitats. The shade tolerance of perenniel-leaved plants can be considered a preadaptation to snow tolerance. In contrast with the perennial-leaved plants, biennial-leaved plants with leaves overwintering 1 year appear to be favored in euphotic habitats with high insulation both in spring and in autumn. These species are effective competitors in spring because of rapid emergence of current leaves, probably through retranslocation of resources accumulated in the previous year. Another adaptive trait is found in heteroptic plants simultaneously having summer-green leaves and overwintering leaves; these types of leaves seem to function in predictable and quite different environments in a year. Key words: foliar phenology, growth form, light resource, overwintering leaf, snow cover.

[1] The effects of wind disturbance on forest dynamics and ecosystem CO2 exchange were examined in cool temperate forests of northern Japan during 2004–2008 using eddy covariance (EC) measurements. One site was a young, even-aged, monoculture, deciduous forest; the other was an uneven-aged mixed forest of evergreen and deciduous overstory tree species, including some over 200 years old. On 8 September 2004, a strong typhoon struck the forests, after which leaf and branch amounts decreased in young growth forest, but foliage showed little change in old growth forest. By 2006, foliage at the young-growth forest had recovered to the 2004 pretyphoon state. Average daily accumulated gross primary production (GPPd), terrestrial ecosystem respiration (TERd), and net ecosystem exchange (NEEd) were assessed for six growth stages annually. After the typhoon, large increases in GPPd were found during the growing stage of overstory tree species with high photosynthetic rates compared to that before the typhoon. Pronounced increases in GPPd and corresponding large reductions in NEEd were detected at the young-growth forest, indicating that NEEd was largely regulated by GPPd throughout the growing stages. Although EC measurements contain uncertainty, our continuous EC measurements revealed that interannual variability in meteorological variables and structural changes in foliage have only small impacts on GPP and NEE, while photosynthetic recovery of foliage from typhoon damage has high potential to increase GPP and enhance NEE as compared with those under nondamage conditions.