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Plant diets of 2 sympatric species of wood mice in Japan (Apodemus argenteusand A. speciosus) were determined by DNA meta-barcoding analyses of feces using the nucleotide sequences of the chloroplast trnLP6 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. argenteuswas less dependent on Fagaceae species than A. speciosus. Instead, A. argenteushad 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. argenteusfrom June to August, and by A. speciosusfrom August to October. The results suggested that A. argenteusis a generalist feeder, and A. speciosusa specialist, and the 2 Apodemusspecies separate their dietary niches not only by the component plant species overall, but also by differences within seasons.

Abstract: 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.

AbstractWindthrow 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.

Abstract: 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.

AbstractWe investigated how removal of understory dwarf bamboo (Sasa kurilensisMakino et Shibata) affected growth and water use of young Betula ermaniiCham. 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. ermaniitrees 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. ermaniitrees 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 studied the effects of prostaglandins and their precursors in animal models. Rabbit ductus arteriosus constricted rapidly after delivery. PGE1, PDE2, and arachidonic acid injected SC dilated the ductus over 60 min. Orogastrically administered PGE2dilated the ductus for 3 hr. PGF2, and arachidonic acid showed weak ductus-dilating effects. Response of the ductus to PGE1was most prominent in the first hr after birth. Pretreatment with indomethacin blocked the ductus-dilating effect of arachidonic acid.

This study was conducted to investigate myocardial excitation-contraction coupling in the fetus of the diabetic rabbit (FDM). On day 14 of gestation, diabetes was induced in pregnant rabbits by alloxan injection. On day 28 of gestation, mechanical function of the fetal myocardium was determined in the isolated arterially perfused heart preparation. At 1.5 mM Ca2o(control), the force of myocardial contraction in FDM was not significantly dfferent from that in the control fetus. At higher Ca2o, developed tension and maximal rate of tension development dT/dt (max) in FDM were significantly greater than in the control fetus. High Ca2ocaused significant increases in resting tension and half-relaxation time (toxic effects) in the control fetus, but not in FDM. Perfusion with lanthanum (known to displace sarcolemma-bound Ca2and block sarcolemmal Na-Ca exchange) decreased developed tension and dT/dt (max) and increased resting tension and these effects in FDM were significantly less than in the control fetus. Perfusion with manganese (known to displace Ca2from intracellular sites) also decreased developed tension and dT/dt (max) and increased resting tension, and these effects were similar in the two groups. The myofibrillar ATPase activities at various calcium concentrations were not different between the two groups. The rates of Ca2uptake by mitochondria and sarcoplasmic reticulum were similar in the two groups. These data suggest that in FDM the inotropic effect of Ca2is greater and the toxic effect of Ca2is less than in the control fetus. This difference may be due, at least in part, to a sarcolemmal alteration induced by the maternal diabetes.

This study determines the inotropic effects of prostaglandin D2(PGD2) and prostaglandin E1(PGE1) in the isolated, arterial perfused newborn (NB) and adult (A) rabbit heart.

ABSTRACT: This study determines the inotropic effects of prostaglandin D2(PGD2) and prostaglandin E1(PGE1) in the isolated, arterial perfused newborn (NB) and adult (A) rabbit heart.Significant positive inotropism of PGD2was observed at all concentrations studied (1 × 10-17to 1 × 10-7M) in the two age groups; the effect in the NB was significantly greater (p < 0.05) than that in the A at PGD2concentrations higher than 1 × 10-17M. Significant positive inotropism of PGE1was observed at PGE1concentrations higher than 1 × 10-8M in the NB, and only at 1 × 10-6M in the A.In the NB, the relaxation parameters [1/2ART and the ratio of +dT/dt (max) to -dT/dt (max)] decreased to 80% of control after PGE1infusion, but not after PGD2infusion. In contrast, relaxation parameters in the A were not different from control.Propranolol (1 × 10-6M) did not alter the positive inotropic action of PGD2and PGE1in the NB. These data indicate that: 1) the positive inotropic effects of PGD2and PGE1in NB are greater than that in the A, 2) PGE1and not PGD2, enhances myocardial relaxation only in the NB,3) the contractile effects of PGD2and PGE1are not mediated by ß-receptors.

ABSTRACT: This study was conducted to investigate myocardial excitation-contraction coupling in the fetus of the diabetic rabbit (FDM). On day 14 of gestation, diabetes was induced in pregnant rabbits by alloxan injection. On day 28 of gestation, mechanical function of the fetal myocardium was determined in the isolated arterially perfused heart preparation. At 1.5 mM [Ca2+]o(control), the force of myocardial contraction in FDM was not significantly dfferent from that in the control fetus. At higher [Ca2+]o, developed tension and maximal rate of tension development [+dT/dt (max)] in FDM were significantly greater than in the control fetus. High [Ca2+]ocaused significant increases in resting tension and half-relaxation time (toxic effects) in the control fetus, but not in FDM. Perfusion with lanthanum (known to displace sarcolemma-bound Ca2+and block sarcolemmal Na-Ca exchange) decreased developed tension and +dT/dt (max) and increased resting tension and these effects in FDM were significantly less than in the control fetus. Perfusion with manganese (known to displace Ca2+from intracellular sites) also decreased developed tension and +dT/dt (max) and increased resting tension, and these effects were similar in the two groups. The myofibrillar ATPase activities at various calcium concentrations were not different between the two groups. The rates of Ca2+uptake by mitochondria and sarcoplasmic reticulum were similar in the two groups. These data suggest that in FDM the inotropic effect of Ca2+is greater and the toxic effect of Ca2+is less than in the control fetus. This difference may be due, at least in part, to a sarcolemmal alteration induced by the maternal diabetes.

Summary: We studied the effects of prostaglandins and their precursors in animal models. Rabbit ductus arteriosus constricted rapidly after delivery. PGE1, PDE2, and arachidonic acid injected SC dilated the ductus over 60 min. Orogastrically administered PGE2dilated the ductus for 3 hr. PGF2, and arachidonic acid showed weak ductus-dilating effects. Response of the ductus to PGE1was most prominent in the first hr after birth. Pretreatment with indomethacin blocked the ductus-dilating effect of arachidonic acid.Speculation: Ductus-dilating effect of SC injected arachidonic acid present further support for the presumed role of the prostaglandins in maintenance of patency of the ductus arteriosus in infants with prematurity or severe congenital heart disease.The mechanism of age-related responsiveness of the ductus arteriosus to PGE1and can be studied in animal model, and this approach may provide additional understanding and suggest new methods of management of the ductus arteriosus which is unresponsive to current medical manipulation.

Abstract

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.

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.

Effects of climatic factors on plant distribution in the Chubu District, central Japan, were examined with direct gradient analysis. The distribution of many species was controlled not only by temperature but also by snowfall.Sasa kurilensis, Heloniopsis orientalis andTripterospermum japonicum preferred snow regardless of the thermal conditions. The snow seemed to exert more influence on endemics than on the more widespread plants, on evergreen plants more than on deciduous plants, and on trees or shrubs more than on herbs or climbing plants. Thus, the snow factor contributes to the high endemic ratio of central Japan. Among the snow-tolerant evergreen shrubs there were many neo-endemics derived from snow-intolerant parent populations of the species which have restricted distributions in the laurel forests. They could occupy habitats in the summergreen forests, where their life form can withstand heavy snowfall. Because of the heavy snowfall on the Sea of Japan side of central Japan in the postglacial period, evergreen coniferous trees have lost many of their previous habitats since most of them are intolerant of heavy snowfall.

The surface reflection intensity of a tungsten-lamp light source at a platinum electrode changes with the electrolytic formation of colored radical ion; the method serves as a convenient means of obtaining an absorption spectra. An example is shown for the radical cation and anion of 9,10-diphenylanthracene in acetonitrile.

It is now clear that a high-dose intravenous immunoglobulin therapy (IVIG) in patients with Kawasaki disease (KD) is effective for reducing the incidence of coronary arterial lesions (CAL). But both the total dose and the dose regimens of IVIG are still controversial.In this study, we report two cases with CAL in KD. These two cases were treated with aspirin (30mg/kg/day) and a single high-dose IVIG (1g/kg/day) on 5thday of illness. IVIG reduced their body temperature immediately to less than 37.5°C on 6thday of illness, so we did not add IVIG. Although they did not get high fever, and both the counts of white blood cells and the levels of C-reactive protein decreased after IVIG, their coronary arteries dilated gradually. In one case, the diameter of anterior descending branch of left coronary dilated to 4.0mm. In the other case, that of left main coronary artery dilated to 5.8mm. We confirmed these changes regressed to normal by either 2DE or selective coronary angiography after three months of onset. These cases suggest that a single high-dose IVIG (1g/kg/day) can not prevent CAL in KD, even after good response to IVIG.

I) T cell receptor (TCR) usage We investigated TCR usage and antibody responses to streptococcal pyrogenic exotoxin-C (SPE-C) in order to determine whether an association exists between SPE-C and the onset of Kawasaki disease (KD). Patients and Method Fifty-four patients with KD were studied. Analysis of TCR usage was performed by adaptor-ligation PCR and microplate hybridization assay. Serum levels of antibody against SPE-C were assessed by ELISA using purified recombinant protein. Results Forty (74.1%) of the patients with KD showed significant polyclonal activation of Vß2- and/or Vß-6.5-bearing T cells. In 22 of 35 paired patients with KD, serum levels of anti-SPE-C antibodies (IgM) in the convalescent phase were lower than those in the acute phase. II) Detection of autoantibodies against vascular smooth muscle cells To investigate the pathogenesis of vasculitis in KD, we tested for the presence of autoantibodies against vascular smooth muscle cells in the patients. Patients and Methods Sera from 48 patients with KD were examined for reactivity with both coronary arterial wall tissues and cultured smooth muscle cells (CSMC) derived from human coronary artery, using immunofluorescence and Western immunoblotting. Results Sera from 16 of 48 patients with KD gave positive immunoreactions with the smooth muscle cells of coronary artery with anti-human IgA antibodies. Western immunoblotting revealed positive reactions of sera from 15 of 34 and 10 of 31 patients with KD against a 70-kDa protein from CSMC with IgA and IgM antibodies, respectively. Positive immunoreactivity of sera from KD patients was detected more frequently in patients with coronary arterial lesions (CAL) than in those without CAL (p <0.05). Conclusions These results suggest that an association may exist between SPE-C and the onset of KD. In addition, autoantibody against vascular smooth muscle cells may cause systemic vasculitis in KD.

Diagnostic guideline of Kawasaki Disease has not been revised since 1984. There has been several progressions during these years concerning management of Kawasaki disease. So a subcommittee for the revision of the diagnostic guideline was organized in the Kawasaki Disease Research Committee to meet the present situation. A draft of new diagnostic guideline was made this year and the final revision will be published next year. Major alterations in this new daft are summarized as follows:1. Cases with 4 or less febrile days shortened by early IVIG treatment were proposed to be equivalent to cases with 5 or more febrile days in the previous criteria. The reason is that many experienced pediatricians have made a diagnosis of Kawasaki disease for the cases even before the 5th febrile day when there were other principal symptoms of Kawasaki Disease. The latest 16th Japanese nationwide surveillance has shown that approximately 10% of patients (total 12,829) started to receive IVGG treatment on or before the 3rd day of illness and 30% of them before 4th day. And also some cases became afebrile before the 5th febrile day when single high dose IVIG was given. 2. The clinical importance of atypical (incomplete) cases is emphasized in the new diagnostic guideline since even atypical cases often developed coronary artery abnormalities and also the incidence of coronary artery abnormality is not significantly different between typical cases and them. 3. The order of 6 principal symptoms of Kawasaki disease was rearranged from head to toe (except for fever and cervical lymphadenopathy) to remember easily: 1. Fever, 2.Conjunctiva congestion, 3.Changes of lips and oral cavity, 4. Rash, 5.Changes of extremities, 6. Cervical lymphadenopathy.

Objectives and Background: In the giant aneurysm(g-AN), thrombus will be produced easily and will occlude coronary artery. But, it is difficult to detect the thrombus in the g-AN, because the slow and turbulent flow in the g-AN show the similar signal intensity with the thrombus. We assessed the diagnostic value of gadorinium (Gd-DTPA) enhanced 3D coronary MR angiography (3D-MRCA) with retrospective respiratory gating to detect the thrombus in the g-AN. Methods: 3 patients (1year-old girl, 11 year-old boy, 17 year-old male) with 6 g-ANs were examined. Only one g-AN in the LAD was occluded by thrombus. We used an ECG-gated 3D segmented turbo FLASH sequence. Images were obtained during free breathing used respiratory gating in which navigator echoes have been used to track the diaphragmatic motion. During scan we injected Gd-DTPA (0.02-o.o3 mmol/kg) manually. Result: The time to examine was 3 to 6 minute. All g-AN were imaged clearly. The signal intensity in g-ANs scanned without Gd-DTPA was low because of low signal blood flow by presaturationed pulses in the right lung to monitor the movement of the diaphragm, but one g-AN (occluded)in the LAD showed high signal intensity. The signal intensity in all of g-AN with Gd-DTPA was high.But in the occluded g-AN of the LAD, low signal area was surrounded with high signal narrow area. Conclusions: These results show that the signal intensity in the g-AN without trombus is low and that with thrombus is high by 3D-MRCA without Gd-MRCA. On the other hand, the signal intensity without thrombus is high and that with thrombus is low by Gd-DTPA enhancement. 3D-MRCA enhanced by Gd-DTPA is useful noninvasive method to detect the thrombus in the g-AN.

Effects of ouabain (0.75, 1, 1.5, 2.5, or 5 × 10−6M) on mechanical function and sodium pump were studied in the isolated arterially perfused fetal and newborn rabbit heart. Measurements of myocardial 86Rb+active uptake was used as a marker of the sodium pump activity. The inotropic effect of ouabain in the fetus was not significantly different from that in the newborn at all ouabain concentrations. 2.5 × 10−6M ouabain caused mechanical toxicity in the fetus but not in the newborn. In the fetal muscle, perfusion with low calcium (0.5 mM) solution reduced mechanical toxicity of ouabain. High extracellular calcium (30 mM) per se caused mechanical toxicity in the fetus, but not in the newborn. Ouabain infusion decreased tissue potassium content, and this decrease in the fetus was not significantly different from the newborn. The ouabain inhibition of Rb+uptake was similar in the two age groups. These data indicate that mechanical toxicity in the fetus is observed at lower ouabain concentrations than in the newborn. This difference in mechanical toxicity may not be explained by the age-related difference in sodium pump activity. The greater calcium toxicity in the fetus may be the reason for the increased ouabain toxicity in this age group.

Effect of 60 min hypoxia (N2) and subsequent 40 min reoxygenation (re-02) on mitochondrial state 3 respiration (QO2), electron transport complexes (ETC), adenine nucleotides (AdN= ATP+ADP+AMP) and adenine nucleotide translocase (AdNT) activity were studied in isolated, arterially perfused newborn (NB) and adult (A) rabbit hearts. In the oxygenated muscle (control) QO2, AdNT and ATP were significantly (P<0.05) greater in NB than in A. After N2, QO2and AdNT decreased significantly (P<0.01) in both age groups, and the values of Q02, AdN, and AdNT in the NB were significantly greater (P<0.05) than in A. N2depressed ETC I in the A but not in the NB. After re-02, QO2and AdN returned to control values in NB (96 ± 10% of control) but not in A (56 ± 3%), and the recovery of AdNT in NB (70 ± 2%) was significantly greater than in A (39 ± 5%). There was good correlation between QO2and AdN as well as AdNT in both age groups. Conclusion: 1) the effect of N2and re-02on Q02, AdN, AdNT and ETC in NB is less than in A, 2) AdN is important in maintaining mitochondrial function.

The purpose of this study was to determine the effects of PGE1and PGD2on mechanical function in the developing heart. The study was performed in the isolated, arterially perfused heart preparation of the newborn (NB) (N=34) and adult (A) (n=27) rabbits. Parameters of mechanical function [developed tension, maximal rate of contraction (+dT/dt), and relaxation (-dT/dt), and half relaxation time (1/2RT)] were recorded continuously. Positive inotropic effect was observed after PGE1or PGD2infusion in both NB and A. The effects of these drugs on +dT/dt (% of control) were:In NB, the relaxation parameters (1/2 RT and the ratio of +dT/dt to -dT/dt) decreased to 80% of control after PGE1infusion but not after PGD2infusion. In A, relaxation parameters were not different from control. These data indicate that 1) the positive inotropic effects of PGE1and PGD2in NB are greater than in A, and 2) PGE1, not PGD2enhances myocardial relaxation only in the NB.