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We measured the evapotranspiration from the understory vegetation and the whole ecosystem of a Siberian larch forest on the forest floor and above the forest canopy, respectively, using the eddy-covariance method, and obtained the year-to-year difference in evapotranspiration during the early (from 1st to 10th), middle(11th to 20th) and late (21th to the end) periods of month. The year-to-year differences in evapotranspiration from whole ecosystem and understory vegetation were in the range from -11.0 mm to 9.5 mm and from -2.4 mm to 4.7 mm, respectively. These values explained from 20% to 30% of monthly mean evapotranspiration, and thus significant differences were found in this site. To clarify the factor controlling the year-to-year difference in evapotranspiration, we analyzed the relationships among the year-to-year differences in evapotranspiration, radiative and advective terms of Penman–Monteith equation. As a result, due to the small value of decoupling factor of this forest, the most important factor was the year-to-year difference in the advective term. We found that the difference in vapor pressure deficit resulting in the change of the surface conductance was important for year-to-year difference in the advective term in this site.

This paper aims to describe in detail the operation principle and unique properties of the output of solid-state seeded CO2 laser, such as multi-line operation, excellent spectro-temporal stability and pulse waveform control.

Boreal Eurasia is a region where the interaction between droughts and the carbon cycle may have significant impacts on the global carbon cycle. Yet the region is extremely data sparse with respect to meteorology, soil moisture, and carbon fluxes as compared to e.g. Europe. To better constrain our vegetation model SiBCASA, we increase data usage by assimilating two streams of satellite-derived soil moisture. We study whether the assimilation improved SiBCASA's soil moisture and its effect on the simulated carbon fluxes. By comparing to unique in situ soil moisture observations, we show that the passive microwave soil moisture product did not improve the soil moisture simulated by SiBCASA, but the active data seem promising in some aspects. The match between SiBCASA and ASCAT soil moisture is best in the summer months over low vegetation. Nevertheless, ASCAT failed to detect the major droughts occurring between 2007 and 2013. The performance of ASCAT soil moisture seems to be particularly sensitive to ponding, rather than to biomass. The effect on the simulated carbon fluxes is large, 5–10 % on annual GPP and TER, tens of percent on local NEE, and 2 % on area-integrated NEE, which is the same order of magnitude as the inter-annual variations. Consequently, this study shows that assimilation of satellite-derived soil moisture has potentially large impacts, while at the same time further research is needed to understand under which conditions the satellite-derived soil moisture improves the simulated soil moisture.

During the Asian monsoon period, intense precipitation commonly occurs for an extended period in accompaniment with a reduction in solar radiation. This suggests that wet surface evapotranspiration is an important contributor to the total evapotranspiration. Therefore, investigating evapotranspiration over a wet canopy surface is critical to achieve a better understanding of water and energy cycles in Asia. In this study, we estimated surface resistances under wet conditions in a mixed forest influenced by the East Asian monsoon system. We showed that the surface resistance had a non-negligible magnitude of about 30 sm−1 even under wet conditions. We also found that the ratio between the actual and potential evapotranspiration depended on the friction velocity regardless of the time of day. Our analyses suggest that this dependency is tightly related to the underestimation of turbulent fluxes by the eddy-covariance system under wet surface conditions. Together, our findings suggest that the wet surface resistance, although small, should be considered in simulating evapotranspiration because the forest ecosystem is strongly coupled to the overlying atmosphere. This could significantly improve the shortcomings of evapotranspiration measurement and modeling in Asian forest canopies influenced by the monsoon system. Copyright © 2012 John Wiley & Sons, Ltd.

We isolated the entire sequence of the coding region of Waxy gene of a non-waxy accession of Job’s tears (Coix lacryma-jobi) by PCR-based methods. We also compared the entire sequences of the gene between two non-waxy accessions and three waxy cultivars and found a 275-bp deletion in the coding region (exons 10–11) of this gene specific to waxy cultivars. We showed by PCR genotyping that this deletion is commonly found in Japanese and Korean cultivars and confirmed that this deletion resulted in lack of Wx protein. We also confirmed that this polymorphism of the gene co-segregates with phenotypes in endosperm and pollen. These results suggest that this PCR-based marker will be useful in breeding of Job’s tears and that genetic information obtained in other grass species will be also useful in genetics and breeding of Job’s tears.

Although SPE-39 is a binding protein to Vps33B that is one of the subunit in the mammalian HOPS complex, the elements of SPE-39 function remain unknown. Here, we show that tyrosine phosphorylation of SPE-39 following EGF stimulation plays a role in the stability of SPE-39 itself. Ubiquitination of the C-terminal region of SPE-39 was also elevated in response to EGF stimulation, and this process was regulated by the phosphorylation of Tyr-11 in SPE-39. However, association of Vps33B with SPE-39 inhibited the elevation of ubiquitination of SPE-39 following EGF stimulation, which might be responsible for the stabilization of SPE-39. Furthermore, an opposing functional relationship between SPE-39 and Vps33B on the downregulation of the EGF receptor was observed in EGF-stimulated COS-7 cells.Structured summary of protein interactionsVps33B and EGFR colocalize by fluorescence microscopy (View interaction)Vps33B and SPE-39 physically interact by anti bait coimmunoprecipitation (View interaction)Vps33B and SPE-39 physically interact by anti tag coimmunoprecipitation (View interaction)Vps33B and SPE-39 colocalize by fluorescence microscopy (View interaction)

In a deciduous larch forest in eastern Siberia, the mean and standard deviation of the total evapotranspiration (E) during May to September (day of year (DOY) = 121–274) for 2003–2006 were 181.5 and 26.4 mm, respectively. The interannual variation (IAV) in the total E was caused by the IAV in E for the canopy-foliated period (DOY = 164–253), not by the IAV in the dates of leaf expansion and leaf fall. For the years with higher total E, E in the canopy-foliated period was consistently higher, which corresponded to the higher soil water content in these years. Copyright © 2012 John Wiley & Sons, Ltd.

A stomatal conductance-photosynthesis-energy balance model developed by Leuning is used to estimate CO2 and H2O fluxes of temperate mixed forests.The canopy is divided into multiple layers,using both Gaussian integration and average-layer method.The fluxes are calculated layer by layer and then accumulated for the whole canopy.The model calculates CO2 and H2O exchange between atmosphere and canopy based on the input of meteorological variables.We compare the modeled fluxes with those measured by eddy covariance system,and analyze the influence of different layer-methods on the modeled fluxes.The energy balance ratios(EBR) of CBS,GDK and MMF sites are 0.76,0.66 and 1.07,respectively,which is reasonable according to the international reported range(0.34—1.2).The results of the Gaussian integration method agree well with the eddy covariance fluxes,showing the diurnal CO2 fluxes as bell shaped.The CO2 flux(Fc) is negative and stable during the night,which suggests that forest ecosystems release CO2 to the atmosphere.After sunrise,Fc increases gradually to positive values,peaking at noon,and decreases in the afternoon to the negative night values.The diurnal cycle of H2O fluxes(LE) is similar to that of Fc,and the modeled LE agree well with the measured LE.The estimated fluxes are influenced by the different layer-methods.We compared CO2 and H2O fluxes from dividing the canopy into 2,5,10 and 20 layers averagely with the fluxes from Gaussian integration method.Larger numbers of layers produce lower LE and higher Fc.The fluxes from different layer-methods are sensitive to the vertical profiles of absorbed radiation,temperature,humidity and wind speed.Furthermore,the leaf photosynthesis responds nonlinearly to the radiation.

Spontaneously Diabetic Torii (SDT) rat is a hereditary model of diabetes. Although the SDT rat shows severe diabetic complications, the onset of hyperglycemia is late. SDT fatty rat, established by introducing the fa allele of the Zucker fatty rat to SDT rat, develops diabetes much faster than SDT rat. In the present study, diabetic peripheral neuropathy (DPN) was evaluated to show the further usefulness of this animal model. Motor nerve conduction velocity (MNCV) was delayed, and the number of sural nerve fibers was decreased in SDT fatty rat. Treatment of pioglitazone lowered blood glucose level and prevented delay of MNCV in SDT fatty rats. SDT fatty rat is a useful animal model for studies of DPN in type 2 diabetes.

Nutritional regulation plays a critical role to reduce the incidence or progression of diabetes mellitus. In this study, we investigated the effects of a high-fat diet on Spontaneously Diabetic Torii Leprfa (SDT fatty) rats, a novel model for obese type 2 diabetes. The SDT fatty rats were divided into two dietary groups, which were fed a high-fat diet or a standard diet for 18 weeks, from 6 to 24 weeks of age. The calorie intake in the high-fat diet (HF) group was reduced after 10 weeks of age and the group inhibited an incidence of diabetes. Interestingly, the HF induced an increase of serum glucagon-like peptide-1 (GLP-1) levels in SDT fatty rats with refeeding. Fat tissue weights in the HF group increased, but the visceral fat/subcutaneous fat (V/S) ratio decreased. Moreover, histopathological observations revealed an improvement of the pancreatic abnormalities and fatty liver in the HF group. In conclusion, a preventive effect on diabetes in rats fed a high-fat diet has a relation with an increase in incretin hormone, and it might be advantageous for prevention of incidence or progression of diabetes to develop functional foods inducing an increase in incretin hormone.

Various three-dimensional fast spin echo (3D-FSE) sequences are used for non-contrast magnetic resonance angiography (MRA). Differences in the ability to detect vascular stenosis using these sequences, however, have not yet been evaluated. The purpose of this study is to evaluate the usefulness of each sequence for the detection of vascular stenosis by using a vascular phantom. The phantom consisting of silicon tubes with 30% and 70% stenosis of luminal diameter and fluids close to Tinf2/infvalue of blood were used for the study. Non-contrast MRA with half-Fourier acquisition single-shot turbo spin echo (HASTE)-noncontrast magnetic resonance angiography of arteries and veins (NATIVE), sampling perfection with application optimized contrasts using different flip angle evolutions (SPACE)-NATIVE, fresh blood imaging (FBI) and triggered angiography non contrast enhanced (TRANCE) sequences was performed by using the phantom which can be varied in terms of the steady flow velocity. Each stenosis was quantitatively estimated by the stenosis index (SI) calculated from the signal intensities on acquired images. The signal intensity of the non-stenotic vascular site markedly decreased at more than a flow rate of 20 cm/s in all sequences. Significant decrease in the signal intensity was observed in the distal point from the stenosis area on these images acquired by using HASTE-NATIVE and FBI sequences. FBI and TRANCE sequences showed a more accurate SI for 30% stenosis than HASTE-NATIVE and SPACE-NATIVE sequences. SI for 70% stenosis was overestimated in all sequences at 5 cm/s of diastolic flow rate. In conclusion, the ability to detect vascular stenosis on non-contrast MRA image using 3D-FSE sequences depends on the image quality during diastolic phase in the cardiac cycle. FBI and TRANCE sequences are useful to detect the mild arterial stenosis.

The Spontaneously Diabetic Torii (SDT) rat is a novel model for nonobese type 2 diabetes. In this study we investigated the glycolipid metabolic changes with phlorizin-treatment, which inhibits intestinal glucose uptake and renal glucose reabsorption, in male SDT rats. Phlorizin (100 mg/kg, b.i.d., s.c.) was administered for 4 weeks to SDT rats from 20 to 24 weeks of age. As a result, phlorizin reduced the development of hyperglycemia and decreased the hemoglobin A1c (HbA1c) levels. In the liver, phlorizin increased mRNA levels of glucokinase, the enzymes related with the glycogen cascade and the proteins associated with lipid metabolism. In conclusion, chronic administration of phlorizin in SDT rats produced a good glycemic control and an improvement in liver function.

Marbling defined by the amount and distribution of intramuscular fat so-called Shimofuri is an economically important trait of beef cattle in Japan. The Pancreatic lipase (Pnlip) gene involved in energy income and fat regulation has been previously shown to be regarded as possible candidate for a rat Quantitative Trait Locus (QTL) responsible for intramuscular fat content. It is located within the genomic region of a bovine QTL for marbling and thus was considered as a positional functional candidate for the gene responsible for marbling. In this study, we showed that Single Nucleotide Polymorphisms (SNPs) in the bovine PNLIP were associated with the predicted breeding value for beef marbling standard number by analyses using a population of Japanese Black beef cattle. The effect of genotypes at each of the SNPs on the predicted breeding value for subcutaneous fat thickness was not statistically significant. The findings suggest that PNLIP SNPs may be useful for effective marker-assisted selection to increase the levels of marbling in Japanese Black beef cattle.

The Spontaneously Diabetic Torii (SDT) rat is a new model of non-obese type 2 diabetes. In the present study, researchers investigated pathophysiological changes of male SDT rats in pre-diabetic stage from 8-16 weeks of age. In oral glucose tolerance test at 12 weeks of age, SDT rats showed glucose intolerance and decrease of glucose-stimulated insulin secretion. Different doses of Streptozotocin (STZ) were administered to SDT rats or SD rats and the pancreatic weakness was examined. SDT rats treated with STZ at a dose level of 20 mg kg-1 were diabetic within 1 week after treatment whereas SD rats got the diabetes after 30 mg kg-1 STZ was received. Insulin tolerance test was performed at 8, 16 and 24 weeks of age in order to examine the insulin sensitivity and the K value was calculated. Interestingly in SDT rats at 16 weeks of age, insulin sensitivity was increased as compared with that in SD rats. Pathohistological changes in pancreas such as atrophy of islets, multiple irregular projection of islets and islet fibrosis were observed in SDT rats at 15 weeks of age. In this study, SDT rat is a useful model for the analysis of the progression of pre-diabetes and the onset of type 2 diabetes.

Marbling defined by the amount and distribution of intramuscular fat, socalled Shimofuri is an economically important trait of beef cattle in Japan. A rat Quantitative Trait Locus (QTL) responsible for intramuscular fat content has been mapped to the ~10-cM genomic region on chromosome 1 by utilizing the Otsuka Long-Evans Tokushima Fatty (OLETF) rat and OLETF-derived congenic strain. In this study, we have attempted to identify the Quantitative Trait Gene (QTG) for the intramuscular fat content QTL by using the OLETF rat. For this purpose, we performed refinement of the intramuscular fat content QTL genomic region to a ~2.3-cM region by use of informative recombinants selected from the OLETF-derived congenic strain, functional retrieval of positional candidate gene, mRNA level analysis and polymorphism search of physiologically relevant positional candidate gene, Pnlip and analysis of cosegregation of the intramuscular fat content QTL with Variable Number of Tandem Repeat (VNTR) in Pnlip by use of informative recombinants. This study suggests that Pnlip encoding pancreatic lipase is the QTG for the intramuscular fat content QTL.

Aim: Microsomal triglyceride transfer protein (MTP) takes part in the mobilization of triglyceride-rich lipoproteins from enterocytes and hepatocytes. We investigated the effects of JTT-130, a novel intestine-specific MTP inhibitor, on impaired glucose and lipid metabolism in Zucker diabetic fatty (ZDF) rats. Methods: Male ZDF rats were fed a regular powdered diet with or without JTT-130 as a food admixture (0.01–0.02%) for 6 weeks. Food intake, body weight, blood biochemical parameters, fecal lipid contents, hepatic lipid contents, tissue mRNA levels and glucose utilization in adipose tissues were assessed. An intraperitoneal glucose tolerance test (IPGTT) and histological analysis of the pancreas were performed. Results: JTT-130 treatment decreased food intake, glycated hemoglobin, plasma levels of glucose, triglycerides and total cholesterol, hepatic levels of triglycerides and cholesterol and hepatic mRNA levels of glucose-6-phosphatase, phosphoenolpyruvate carboxykinase and fructose-1,6-bisphosphatase. JTT-130 treatment increased fecal levels of free fatty acids and cholesterol, plasma levels of glucagon-like peptide-1 and peptide YY, mRNA levels of glucose transporter 4 (GLUT4) and lipoprotein lipase in adipose tissues and GLUT4 in muscle and glucose utilization in adipose tissues. Plasma insulin decreased after 2 weeks and increased after 4 weeks of JTT-130 treatment. Plasma glucose in the JTT-130-treated rats was lower with higher plasma insulin than in the control rats during the IPGTT. The islets of the JTT-130-treated rats were larger and contained more insulin than those of the control rats. Conclusions: JTT-130 ameliorates impaired glucose and lipid metabolism in the ZDF rats thereby suggesting that JTT-130 could be useful for prevention and treatment of type 2 diabetes.

Boreal forests play an important role in the global balance of energy and CO 2 . Our previous study of elaborate eddy covariance observations in a Siberian boreal larch forest, conducted both above the forest canopy and at the forest floor, revealed a significant contribution of latent heat flux ( LE ) from the cowberry understory to the whole ecosystem LE . Thus, in the present study, we examined what factors control the partitioning of whole ecosystem LE and CO 2 flux into the understory and overstory vegetation, using detailed leaf-level physiology (for both understory and overstory vegetation) and soil respiration property measurements as well as a multilayer soil-vegetation-atmosphere transfer (SVAT) model. The modeling results showed that the larch overstory's leaf area index (LAI) and vertical profile of leaf photosynthetic capacity were major factors determining the flux partitioning in this boreal forest ecosystem. This is unlike other forest ecosystems that tend to have dense LAI. We concluded that control of the larch overstory's LAI had a relationship with both the coexistence of the larch with the cowberry understory and with the water resources available to the total forest ecosystem.

Diabetic animal models play critical roles in the elucidation of the mechanisms of diabetes mellitus and the complications, and in the development of novel drugs as treatments. Spontaneously Diabetic Torii Lepr fa (SDT fatty) rat, established by introducing the fa allele of the Zucker fatty rat into SDT rat genome, is a new model of obese type 2 diabetes. We have investigated the characteristics of SDT fatty rats. Both male and female SDT fatty rats show overt obesity, and hyperglycemia and hyperlipidemia are observed at a young age as compared with SDT rats. With early incidence of diabetes mellitus, diabetic complications in SDT fatty rats were seen at younger ages than those in the SDT rats. Furthermore, we evaluated the pharmacological effects of anti-diabetic drugs, such as metformin, pioglitazone, and dipeptidyl peptidase-4 inhibitor on SDT fatty rats. SDT fatty rat is a useful model for analysis of metabolic disease and the evaluation of drugs related to metabolic disease.

The impairment of glucose metabolism may lead to type 2 diabetes and the malfunction of lipid metabolism contributing to metabolic syndrome, which increases risk of heart disease, vascular disease, and type 2 diabetes. Our previous study provided evidence for involvement of hepatic glucose metabolic disorder in onset and progress of diabetes in Spontaneously Diabetic Torii (SDT) rats. As it is increasingly important to elucidate the mechanism of onset of diabetes and to develop drugs to prevent diabetic pathological progress, SDT rat should offer a highly useful model of spontaneous diabetic onset for such studies. In addition, abnormality in triglyceride (TG) absorption and impaired lipid catabolism antecedent to hypoinsulinemia/hyperglycemia seem to cause postprandial hypertriglyceridemia in SDT rat; hence, the characteristics of lipid metabolism in SDT rat can be useful in studies of diabetic hypertriglyceridemia and TG metabolism.

Diabetic nephropathy is a serious complication of diabetes mellitus, making it essential to develop animal models of diabetic complications to simulate the pathogenesis in humans. We monitored pathobiochemical parameters and histopathological findings of kidneys in male Spontaneously Diabetic Torii (SDT) rats. Renal-related parameters in SDT rats have deteriorated with the progress of diabetes mellitus, and histopathological changes in the renal tubules and the glomeruli were observed with aging. Glycemic control in SDT rats prevented the development of renal lesions. The features of SDT rat indicate its usefulness as an animal model for investigating diabetic nephropathy.

To aid in the study of diabetes and its complications, many diabetic animal models have been reported. Although most diabetic patients suffer type 2 diabetes, studies using type 2 diabetic animal models have been carried out less frequently. Spontaneously Diabetic Torii (SDT) rat, a non-obese type 2 diabetes model, shows neuropathies and severe ocular complications. Decreased nerve conduction velocity and thermal hypoalgesia were improved by insulin treatment, indicating that the peripheral neuropathies in SDT rats are caused by sustained hyperglycemia. Autonomic nerve dysfunctions such as decreased coefficients of variance of R-R intervals (CVR-R) in electrocardiogram, functional gastrointestinal disorders, and voiding dysfunction are also observed in SDT rats. Therefore, SDT rat is a useful diabetic animal model for studies of diabetic neuropathies in type 2 diabetes and development of new drugs and therapies for diabetic neuropathies.

A portable NMR polarimeter system has been developed to measure the polarization of a polarized Hydrogen-Deuteride (HD) target for hadron photoproduction experiments at SPring-8. The polarized HD target is produced at the Research Center for Nuclear Physics (RCNP), Osaka university and is transported to SPring-8. The HD polarization should be monitored at both places. We have constructed the portable NMR polarimeter system by replacing the devices in the conventional system with the software system with PCI eXtensions for Instrumentation (PXI). The weight of the NMR system is downsized from 80 kg to 7 kg, and the cost is reduced to 25%. We check the performance of the portable NMR polarimeter system. The signal-to-noise (S/N) ratio of the NMR signal for the portable system is about 50% of that for the conventional NMR system. This performance of the portable NMR system is proved to be compatible with the conventional NMR system for the polarization measurement., Comment: 6 page, 8 figures, 2011/Mar/9 Replace Authors

Evapotranspiration (ET) is not only a vital component of water budget, but also plays an important role in the energy budget of the earth-atmospheric system, ultimately driving many regional and global scale climatological processes. This paper describes the ET characteristics and factors controlling ET across the 17 forest sites in East Asia (2°S to 64°N latitude). ET was measured using the eddy covariance technique at each site. Daytime dry-canopy data for the growing season were used in this study. Growing season mean ET gradually decreased as latitude increased, with a range of 4.4 to 1.2 mm d−1. The growing season mean decoupling coefficient (Ω) ranged from 0.42 to 0.11 across the studied sites. At low-latitude forest sites, Ω was close to 0.50, indicating that the bulk surface was partially decoupled from the atmosphere and ET was strongly controlled by net radiation and vapour pressure deficit. At high-latitude forest sites, Ω was low (∼0.12), indicating that the bulk surface was well coupled to the atmosphere and ET was mainly controlled by surface conductance. The value of Ω was determined mainly by the ratio of aerodynamic conductance to surface conductance across the studied forests of East Asia.

Decline of larch trees has been recently observed in eastern Siberia. We hypothesized that the decline might be caused by changes in soil water conditions of larch forests, especially wetting tendency due to recent climate change. Through pot experiments, we have investigated the effects of wet or dry soil water conditions on growth and abscission of roots in two larch species viz. Larix gmelinii that grows in boreal forests and Larix leptolepis that grows in temperate regions. The results showed that both the allocation of photosynthetic products to roots and the activity of roots decrease under wet conditions compared with drought conditions in L. gmelinii. However, the opposite results were obtained in L. leptolepis. The root response of L. gmelinii to wet conditions may be one of the causes of the recent decline in Siberian larch forests under elevated soil water conditions.

The Spontaneously Diabetic Torii (SDT) fatty rat, established by introducing the fa allele of the Zucker fatty rat into the SDT rat genome, is a new model of obesity/type 2 diabetes. The present study investigated effects of food restriction on metabolic and endocrinological function in SDT fatty rats. SDT fatty rats were pair-fed with SDT rats from 7 to 21 weeks of age. The SDT fatty rats were already hyperinsulinemic and hyperlipidemic at 7 weeks of age. After 7 weeks of age, SDT fatty rats showed age-dependently increasing serum glucose levels associated with decreasing serum insulin levels. However, in pair-fed SDT fatty rats, hyperglycemia and hyperinsulinemia were attenuated at 9 weeks of age. After 9 weeks of age, the serum insulin levels unexpectedly increased in the pair-fed SDT fatty rats. Glucose tolerance was also improved, and the pancreatic insulin contents were increased in these rats. Pancreatic islets were hypertrophied in pair-fed SDT fatty rats compared with ad lib-fed SDT fatty rats, which were comparable to SDT rats. This study showed that, in SDT fatty rats, calorie restriction by paired-feeding with SDT rats attenuated hyperglycemia and hyperinsulinemia for the first 2 weeks. Thereafter, the serum insulin levels and pancreatic insulin contents were increased, though the restriction was continued. Hypertrophic pancreatic islets were also remarkable, indicating increased beta cell proliferation. The activated pancreatic beta cell functions might be due to rapid food ingestion, a change of feeding behavior resulting form increasing the fasting period, which was indispensable for calorie restriction.

Evapotranspiration over forest surfaces is mainly constrained by environmental and forest structural components through their influence on surface conductance (Gs) and aerodynamic conductance (Ga). Tower based eddy covariance data from 16 forest sites in East Asia (2°S to 64°N) were used to examine the sensitivity of Matsumoto and Nakai models for predicting Gs and Ga, respectively. Daytime dry-canopy data for the growing season were used in this study. Comparisons between model predictions and observed Gs and Ga showed good agreement, suggesting that the models were suitable for predicting Gs and Ga with reasonable accuracy. However, the model for Gs was unable to predict Gs accurately when soil water content was low (∼10%). In this circumstance, effective soil water content and a more comprehensive method for modelling the soil water content function must be used. Gs in East Asia was largely depended on vapour pressure deficit and secondarily on soil water content. Ga was largely affected by leaf area index compared with stand density.

A high-sucrose diet induces insulin resistance and dyslipidemia in normal rats. The purpose of the present study was to investigate the effects of a high-sucrose diet on glycolipid metabolism in Spontaneously Diabetic Torii (SDT) rats, a genetic model of nonobese type 2 diabetes. Male SDT rats were fed with a high-sucrose (68% of energy) diet from 8-24 weeks of age. SDT rats fed a high-sucrose diet showed hypercholesterolemia, hyperinsulinemia and hyperleptinemia but the body weight and the serum triglyceride level were not increased. Unexpectedly in SDT rats fed a high-sucrose diet, we observed a suppress of the incidence of diabetes mellitus. In computed tomography analysis, SDT rats fed a high-sucrose diet showed an increase of visceral or subcutaneous fat tissue weight. In pathological analyses, slight or mild fatty liver was observed by high-sucrose feeding. A high-sucrose diet in SDT rats induced dyslipidemia, insulin resistance and fat storage but not development of diabetes. High sucrose-fed diabetic rats are considered to be useful for further elucidation of complex mechanisms in glycolipid metabolic abnormality.

Pancreatic dysfunction is a pivotal factor on incidence and development of diabetes mellitus and especially, the pancreatic weakness is a key defect contributing to diabetes mellitus. In this study, we investigated the pancreatic weakness in obese Zucker Fatty (ZF) rats. Different doses of Streptozotocin (STZ) were administered to ZF rats and the biochemical and the pancreatic related parameters were examined. Wistar rats were used as control animals. Before STZ injection, ZF rats showed a tendency to increase of insulinogenic index as compared with that in Wistar rats but the disposition index in ZF rats was significantly decreased as compared with that in Wistar rats. Moreover, the islets of STZ-untreated ZF rats were larger and had irregular boundaries. ZF rats treated with STZ at a dose level of 20 mg kg-1 were diabetic within one week after the treatment whereas Wistar rats got the diabetic after 30 mg kg-1 STZ was received.

Summary The water and energy fluxes in forests fluctuate on different temporal scales, reflecting the impact of environmental factors. We examined the temporal fluctuation of the turbulent fluxes, surface conductance (Gs), and four environmental factors (photosynthetic photon flux density [Q], vapour pressure deficit [D], air temperature [T], and volumetric soil water content [θ]) in a Siberian larch forest, using wavelet power spectra. The responses of the latent heat flux (λE) and Gs to the environmental factors were analysed using the wavelet scale-wise correlation coefficient (SWCC) on multiple temporal scales. The observation site is characterised by underlying permafrost and a relatively short growing season. Analysis was conducted from May to September in each of 8 years during 1998–2007. The relationships between Gs and the environmental factors were evaluated with restrictive functions of a Jarvis-type surface conductance model because Gs usually has non-linear relationships to ambient factors. According to the power spectra of each factor, the largest variation was seen on a diurnal timescale for λE, the sensible heat flux (H), Gs, and Q, whereas D and T fluctuated from diurnal to inter-seasonal timescales, and θ varied significantly over periods longer than the inter-seasonal timescales. The SWCC indicated that λE and Gs respond differently to the same ambient factors due to their respective processes; namely, λE is affected by both atmospheric demand and land surface regulation, whereas Gs is affected only by the latter. λE correlated well with Q at all timescales, as well as with D and T on intra-seasonal to interannual scales and with θ on inter-seasonal to interannual timescales. The SWCC of Gs and Q showed two peaks, on diurnal and inter-seasonal to interannual timescales, reflecting the physiological processes of plants, and D affected Gs only on an intra-seasonal timescale, which is related to meteorological changes. T and θ regulated Gs only on inter-seasonal to interannual scales. These SWCC results for D and θ roughly match previous findings in Siberia. The SWCC also suggested that the recent extremely high soil water has damaged the ecosystem of the eastern Siberian forest. Neither λE nor Gs followed the high θ in the last few years, although the richer soil moisture enhanced them on a long-term temporal scale under the usual soil moisture condition in Siberia.

ESCRT-I, which mediates the sorting of ubiquitinated cargo protein from the plasma membrane to the endosomal vesicle, comprises a heterotetramer of TSG101 (Vps23), Vps28, Vps37 and MVB12 protein. In humans, the structurally similar subtypes MVB12A and MVB12B are subunits of ESCRT-I. However, no functional description of these proteins has been described. Here we show the differing effects of tyrosine phosphorylation and ubiquitination of both MVB12 proteins on their respective functions. As noted in our previous study, Tyr204 phosphorylation of MVB12A in response to epidermal growth factor (EGF) stimulation affects binding to CD2AP, which regulates the amounts of EGF receptor bound to ESCRT-I. Strikingly, ubiquitination of Lys264 and Lys290 of MVB12B was induced and led to the instability and inclusion of MVB12B in COS-7 cells. These ubiquitinations increased upon EGF stimulation, which was regulated by the phosphorylations of Tyr241 and Tyr243 of MVB12B. Furthermore, MVB12A was also involved in the aggregation-prone proteins of MVB12B. These results suggest that the expression of MVB12B may be normally suppressed through the ubiquitin-proteasome pathway that simultaneously regulates the fate of MVB12A and the functions of ESCRT-I.

A consistent measure of forest canopy height is required for among-site comparisons of meteorological properties and for comparison of model results such as distributions of wind and other scalars calculated by large eddy simulations with observations. The aerodynamic canopy height has been proposed as a useful measure of canopy height, which is determined by micrometeorological methods without depending on stand inventory data. However, the aerodynamic canopy height is obtainable only if the necessary meteorological instruments are installed. In this study, we explored an alternative measure of forest canopy height based on tree inventory data. When cumulative trunk basal area from the shortest tree is plotted against corresponding individual tree height, it shows a sigmoidal curve with its inflection point occurring at a height class. The above-ground height of this inflection point (hereafter cumulative basal area inflection (CuBI) height) is defined as forest canopy height, as many tall trees with relatively large basal area belong to this height class. The difference between the aerodynamic canopy height and the CuBI height was always smaller than 12%, whereas the differences exceeded 20% for at least one of the forests when canopy height was determined using alternate methods. This suggests that, unlike other canopy height definitions, CuBI height is a consistent index of the aerodynamic canopy height, little affected by criterion of the trees composing the upper canopy or by the presence/absence of many shorter understory trees. Because chronological changes in size-structure of tree height and trunk diameter have long been studied for many forests, CuBI height may be used as an index of chronological change in the aerodynamic canopy height.

Directed lithiation of N-benzenesulfonyl-3-bromopyrrole (1) with LDA in THF at -78 degrees C generated C-2 lithio species 3 selectively. Reactions of 3 with reactive electrophiles produced the corresponding 2-functionalized pyrroles 4. On the other hand, quenching with less reactive electrophiles generated the corresponding 5-substituted pyrroles 5. The latter unusual functionalization at C-5 could be rationalized by dynamic equilibrium between C-2 and C-5 lithio species.

Aim: Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signalling, is a novel therapeutic target for type 2 diabetes mellitus. We evaluated in vitro and in vivo the pharmacological profiles of a new PTP1B inhibitor, JTT-551: monosodium ({[5-(1,1-dimethylethyl)thiazol-2-yl]methyl} {[(4-{4-[4-(1-propylbutyl)phenoxy]methyl}phenyl)thiazol-2-yl]methyl}amino)acetate. Methods: PTP1B inhibitory activity and the inhibition mode were assayed with p-nitrophenyl phosphate as a substrate, and the selectivity of JTT-551 against other PTPs, including T-cell protein tyrosine phosphatase (TCPTP), CD45 protein tyrosine phosphatase (CD45) and leucocyte common antigen-related protein tyrosine phosphatase (LAR), was evaluated. Glucose uptake with JTT-551 treatment was evaluated in L6 rat skeletal myoblasts (L6 cells). In the in vivo study, we investigated the effects on insulin receptor (IR) phosphorylation and blood chemical parameters with JTT-551 administration in ob/ob mice and db/db mice. Results: JTT-551 showed an inhibitory effect on PTP1B with a Ki value of 0.22 µM, and a mixed-type inhibition mode. Ki values of TCPTP, CD45 and LAR were 9.3, 30 or higher and 30 or higher µM, respectively, and JTT-551 exhibited clear selectivity against the other PTPs. Moreover, JTT-551 increased the insulin-stimulated glucose uptake in L6 cells. A single administration of JTT-551 in ob/ob mice enhanced the IR phosphorylation of liver and reduced the glucose level. In db/db mice, chronic administration showed a hypoglycaemic effect without an acceleration of body weight gain. Conclusions: JTT-551, a newly developed PTP1B inhibitor, improves glucose metabolism by enhancement of insulin signalling and could be useful in the treatment of type 2 diabetes mellitus.

Larch forests are widely distributed across many cool-temperate and boreal regions, and they are expected to play an important role in global carbon and water cycles. Model parameterizations for larch forests still contain large uncertainties owing to a lack of validation. In this study, a process-based terrestrial biosphere model, BIOME-BGC, was tested for larch forests at six AsiaFlux sites and used to identify important environmental factors that affect the carbon and water cycles at both temporal and spatial scales. The model simulation performed with the default deciduous conifer parameters produced results that had large differences from the observed net ecosystem exchange (NEE), gross primary productivity (GPP), ecosystem respiration (RE), and evapotranspiration (ET). Therefore, we adjusted several model parameters in order to reproduce the observed rates of carbon and water cycle processes. This model calibration, performed using the AsiaFlux data, substantially improved the model performance. The simulated annual GPP, RE, NEE, and ET from the calibrated model were highly consistent with observed values. The observed and simulated GPP and RE across the six sites were positively correlated with the annual mean air temperature and annual total precipitation. On the other hand, the simulated carbon budget was partly explained by the stand disturbance history in addition to the climate. The sensitivity study indicated that spring warming enhanced the carbon sink, whereas summer warming decreased it across the larch forests. The summer radiation was the most important factor that controlled the carbon fluxes in the temperate site, but the VPD and water conditions were the limiting factors in the boreal sites. One model parameter, the allocation ratio of carbon between belowground and aboveground, was site-specific, and it was negatively correlated with the annual climate of annual mean air temperature and total precipitation. Although this study substantially improved the model performance, the uncertainties that remained in terms of the sensitivity to water conditions should be examined in ongoing and long-term observations.

A divergent synthesis of three sulfate derivatives of lamellarin α, namely, lamellarin α 13-sulfate (2), 20-sulfate (1), and 13,20-disulfate (4) has been achieved via a common intermediate (6) in which 13-OH and 20-OH of the lamellarin core are differentially protected by MOM and benzyl groups, respectively. Compound (6) in turn was prepared using sequential Suzuki-Miyaura coupling of 3,4-dihydroxypyrrole bistriflate (7) as a key reaction., HETEROCYCLES, 80(2), pp.841-846; 2010

著者人数: 13名, 資料番号: PA0910043000

Introduction Impaired diabetic wound healing is an important issue in diabetic complications. The present study aims to evaluate the protective effect on glycemic control against impaired diabetic wound healing using a diabetic rat model. We investigated the wound healing process and effect on the impaired wound repair by glycemic control in the Spontaneously Diabetic Torii (SDT) fatty rat, which is a new animal model of obese type 2 diabetes and may be a good model for study impaired wound healing. Material and methods Male SDT fatty rats at 15 weeks of age were administered orally with sodium glucose co-transporter (SGLT) 2 inhibitor for 3 weeks. Wounds were induced at 2 weeks after SGLT 2 inhibitor treatment, and the wound areas were periodically examined in morphological and histological analyses. Results The SDT fatty rats showed a delayed wound healing as compared with the normal rats, but a glycemic control improved the impaired wound healing. In histological analysis in the skin of SDT fatty rats showed severe infiltration of inflammatory cell, hemorrhage and many bacterial masses in the remaining and slight fibrosis of crust on skin tissue. Thought that this results skin performance to be a delay of crust formation and regeneration of epithelium; however, these findings were ameliorated in the SGLT 2 inhibitor treated group. Conclusion Glycemic control is effective for treatment in diabetic wounds and the SDT fatty rat may be useful to investigate pathophysiological changes in impaired diabetic wound healing.

A new vibration apparatus for measuring the shear strength of snow has been designed and fabricated. The force applied to a snow block is calculated using Newton’s second law. Results from this apparatus concerning the dependence of the shear strength on snow density, overburden load and strain rate are in reasonable agreement with those obtained from the work of previous researchers. Snow densities ranged from 160 to 320 kg m−3. The overburden load and strain rate ranged from 1.95 × 10−1to 7.79 × 10−1kPa and 2.9 × 10−4to 9.1 × 10−3s−1respectively.

Urbanisation is increasing tremendously in some parts of the world. Consequently, many rural forests may become depleted, although many opportunities exist for urban forests to increase. However, few studies have quantified the carbon (C) sequestration capacities of urban and rural forests in specific climatic zones. The present study compared carbon sequestration in two temperate deciduous forests located in Nagoya and Toyota, central Japan. The Nagoya University forest represented an urban forest, and a site in Toyota represented a rural forest. The urban forest at Nagoya University had comparatively smaller areas of green space and larger areas of buildings and roads. Land uses for building and road, which are typical of urban areas, result in smaller diurnal temperature ranges but higher air temperature, vapour pressure deficit, and atmospheric carbon dioxide (CO 2 ) concentration. The urban forest in this study exhibited higher gross ecosystem exchange (GEE), especially in the active growing season from May to September, suggesting the possible effect of CO 2 fertilisation. However, higher air temperatures caused comparatively smaller net ecosystem exchange (NEE) because of higher ecosystem respiration (RE). Although both forests functioned as CO 2 sinks at annual time scales, the rural Toyota forest site (5.43 t C ha –1 yr –1 ) had 36% higher net ecosystem production (NEP=–NEE; the negative sign indicates uptake by the forest ecosystem from the atmosphere) than that at the urban forest. The higher normalised respiration (i.e., RE/GPP ratio; GPP=–GEE where GPP represents gross primary production) at the Nagoya University forest might be attributable to factors associated with the degree of urbanisation. Thus, in temperate forests, factors associated with urbanisation may reduce the atmospheric carbon sink function by accelerating respiration. This is an issue of global interest, as many countries are experiencing rapid urbanisation.

We measured air temperature in an urban green area that includes forest and grassland and in the surrounding urban area for a full year in Nagoya, central Japan, to elucidate seasonal variations of the difference in air temperature between urban and green areas. We determined the range of the “cool-island” effect as well as the relationship between vegetation cover and air temperature throughout the year. The temperature difference between urban and green areas was large in summer and small in winter. The maximum air temperature difference was 1.9 °C in July 2007, and the minimum was −0.3 °C in March 2004. The difference was larger during the day than during the night in summer, whereas in winter the opposite relationship was true. However, winter diurnal variation was not particularly noticeable, a behaviour thought to be related to reduced shading by deciduous trees in the green area. During the night, the cooling effect of the green area reached 200–300 m into the urban area. During the day, the cooling effect between August and October 2006 exceeded 300 m and varied widely, although there was no correlation beyond 500 m. The correlation between air temperature and forest-cover ratio within a radius of 200 m from each measurement site was significant from 16:00 to 19:00. There was also a correlation during the night; this correlation was weakest in the early morning. The effect of the forest-cover ratio on air temperature was most pronounced in August 2006 and June 2007.

We measured evapotranspiration in an eastern Siberian boreal forest, in which the understory was cowberry and the overstory was larch, during the entire growing seasons of 2005 and 2006. We compared evapotranspiration from the understory vegetation above the forest floor E U with evapotranspiration from the whole ecosystem above the overstory canopy E O . The E U / E O ratio had a seasonal trend with a flat-bottomed U-shape during the growing season (4 May–30 September). High- E U / E O ratios at the beginning and end of the growing season were observed because larch, one of the two sources of E O , was a deciduous tree, while the understory was the evergreen cowberry. The mean daily E U values during the foliated period of larch (1 June–31 August) were 0.8 and 0.9 mm day −1 , or 51.4 and 51.8% of E O in 2005 and 2006, respectively. The understory vegetation was one of the most important components of the hydrologic cycle in this forest. A significant amount of E U was caused by plant physiological control, due to the aerodynamic conductance, which was much larger than the surface conductance, leading to a smaller decoupling coefficient. We found that 71% of E U was caused by the vapour pressure deficit above the forest floor.

Histidine-rich glycoprotein (HRG) promoted the adhesion and morphological changes of human T-cell line MOLT-4 in a Con A-dependent manner. This morphological change-promoting activity was specific for HRG and the Arg23–Lys66 glycopeptide from human HRG. The carbohydrate chain at Asn45 was essential for this activity. The morphological changes of MOLT-4 cells caused by HRG and Con A (HRG/Con A) were not inhibited by phosphatidylinositol 3-kinase inhibitor, wortmannin or LY294002, while the changes by Con A alone were completely inhibited by these reagents, suggesting that HRG/Con A cooperate to activate leukocytes via a signaling pathway distinct from that by Con A alone. The morphological changes by Con A were associated with pseudopodia like structure. On the other hand, the morphological changes caused by HRG/Con A were associated not only with pseudopodia like structure but also with an increase of the F-actin-rich surface protrusions. Wortmannin inhibited only the formation of pseudopodia like structure.

The Spontaneously Diabetic Torii (SDT) rat is a new model for non-obese type 2 diabetes. In the present study, we investigated changes in insulin secretion from the pancreas of male SDT rats aged 8, 16, and 24 weeks in order to analyze pancreatic function. An analysis of glucose-stimulated insulin secretion (GSIS) in isolated islets showed a marked reduction in insulin secretion in pre-diabetic 16-week-old SDT rats. When the islets were treated with tolbutamide or glucagon-like peptide-1 (7-36) amide (tGLP-1) in the presence of 11.2 mM glucose, however, insulin levels were restored to levels of normal rats. In vivo study, SDT rats exhibited a marked reduction in GSIS from 16 weeks of age. However, tolbutamide or JTP-76209, which is a novel dipeptidyl peptidase IV (DPP IV) inhibitor, increased insulin release after glucose loading and improved glucose tolerance. A marked reduction in GSIS was observed in pre-diabetic SDT rats and the reduction was improved by tolbutamide, tGLP-1, and the DPP IV inhibitor. Therefore, we concluded that the SDT rat is useful, as a model of non-obese insulin secretory disorder, for the analysis of the onset of type 2 diabetes and the development of antidiabetic agents.

This paper summarizes and synthesises the results obtained in several recent studies on water and energy exchange of East Siberian forests located on permafrost. It is found that annual evaporation of these forests shows relatively small inter-annual variation (147–196 mm). The availability of stored water in the permafrost probably functions as a buffering resource that is only used occasionally in very dry years. Surface soil water content shows a 1-year memory to precipitation in Eastern Siberia because the precipitation conditions in previous summers carry over in a frozen condition to the next spring. Modelling shows that evaporation was larger for southern forests than for northern forests. Compared to tundra, taiga forest shows a relatively small Bowen ratio. In an alas system, observations show considerable impact of the distribution of lakes in the vicinity on the observed evaporation fluxes. There appeared to be little difference in the observed Bowen ratio between a young and old larch forest. Surface conductance modelling and upscaling studies note that leaf area index (LAI) was a controlling factor in evaporation. With the permafrost area under strong pressure from climate warming, the need to understand the ecophysiological controls of these forests in East Siberia is paramount. With the data and analysis presented in this special issue becoming available we are now in a better position to model the effects of permafrost degradation on water and energy balances.

Water vapor, energy fluxes, and environmental conditions were measured in an eastern Siberian larch forest for 7 water years, from 1998 to 2006, to understand the water-balance characteristics and interannual variation (IAV). The latent heat flux accounted for 38–67% of the sum of turbulent heat fluxes in June, July, and August, a relatively moderate fraction was compared to values measured at mid- and low latitudes. More than 70% of the annual precipitation evaporated during May to September. Annual evapotranspiration, including interception loss, was relatively steady at 169–220 mm compared with the wide range in annual precipitation (111–347 mm year −1 ). The evapotranspiration rate was 1.49–2.30 mm day −1 on a daily basis from May to September above a dry canopy. This feature is one of the remarkable characteristics of the water balance in eastern Siberian forests. The thawing depth of the permafrost has been rapidly deepening since 2004, such that the maximal thawing depth varied from 127 cm before 2003 to over 200 cm after 2004. At the same time, there was a very large increase in the moisture content of the surface soil. This increase could not be explained by the amount of annual precipitation alone and may have been due to inflow from the deeper thawing layer. The IAV of evapotranspiration was small, but the yearly evapotranspiration coefficient (the ratio of evapotranspiration to potential evaporation) ranged from 0.30 to 0.45. These results indicate that the IAV of evapotranspiration is controlled by regulation of the land surface rather than by atmospheric demand. Soil-moisture content was the most important variable among the factors determining the evapotranspiration coefficient at an interannual temporal scale. This result differs somewhat from previous satellite-based findings that air temperature was a major variable for plant activity. This difference might result from the fact that the IAV of soil water content did not correspond to that of the precipitation amount because of the presence of the permafrost. By contrast, the soil water content was strongly affected by precipitation in the previous summer.