Exercise capacity is frequently decreased in patients with chronic obstructive pulmonary disease (COPD), and muscle dysfunction is one factor in this reduction. Studies using ³¹-phosphorus magnetic resonance spectroscopy (³¹P-MRS) have shown that phosphocreatine (PCr) and muscle pH (pHi) are significantly decreased in patients with COPD during mild exercise, suggesting the early activation of anaerobic glycolysis in their muscles. Thus, muscle oxygenation states during exercise might differ between patients with COPD and healthy individuals. We simultaneously measured oxygenation state and pHi in the muscles of patients with COPD during the transition from rest to exercise (on-transition) using near infrared spectroscopy (NIRS) and ³¹P-MRS. Sixteen patients with COPD (aged 68.6 ± 7.5 years) and 7 healthy males (controls; aged 63.3 ± 7.5 years) performed dynamic handgrip exercise (lifting a weight by gripping at a rate of 20 grips per min for 3 min). Patients were classified based on pHi data at the completion of exercise as having a normal (≥ 6.9; n = 8) or a low (< 6.9; n = 8) pHi. The deoxygenated hemoglobin/myoglobin (deoxy-Hb/Mb) in NIRS recordings remained constant or slightly decreased initially (time delay), then increased to reach a plateau. We calculated the time delay and the time constant of deoxy-Hb/Mb kinetics during the on-transition. The time delay was shorter in the group with a low pHi than in the controls. These findings might reflect a slower increase in O₂ delivery in patients with a low pHi, which might partly account for altered muscle energy metabolism.

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RBL-2H3細胞によるβ－ヘキソサミニダーゼ放出阻害活性が認められたヨモギ熱水抽出物と，同様の方法でヨモギ熱水抽出物をクロロゲン酸エステラーゼで処理したヨモギ酵素分解物を得た．ヨモギ酵素分解物のIC₅₀値は0.447 mg/mlでヨモギIC₅₀値と比較すると脱顆粒抑制活性が7倍強くなった．また，カフェ酸含量はヨモギ酵素分解物の4.65％であった．ヨモギ酵素分解物のHPLC分析で得た1画分にも脱顆粒抑制作用が認められた．HPLC画分を解析した結果，カフェ酸と同定されカフェ酸画分のIC₅₀値23.3 g/mlは，ヨモギ酵素分解物のIC₅₀値（0.447 mg/ml）とカフェ酸含有量（4.65％）から推算される値と一致した．このことより，ヨモギ酵素分解物の主要な脱顆粒抑制作用は，カフェ酸に由来することが示唆された．

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示差走査熱量測定 (DSC) より, 高分子のガラス転移温度を正確に決定する方法はRichardson法として知られているが, この方法が実際に適用された例は限られている. このノートでは, 個々のDSC装置に合わせてプログラムを自作することなく, 市販のソフトウェアーを用いてパソコン上で, Richardson法を適用するに必要な, 一連のデータ処理を実行する方法の一例を述べる.

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Aim: Classification of pregnancy induced hypertension (PIH) according to the Japan Society of Obstetrics and Gynecology defines early onset PIH as that which develops before 32 weeks of gestation, and late onset PIH as that which occurs thereafter. The present study aimed to validate this cut-off point.Methods: Clinical characteristics of the patients from 59 domestic tertiary settings of perinatal medicine were analyzed. Women with multiple pregnancies and/or any medical complications were excluded. Subgroups of mild and severe PIH were created according to the severity of hypertension.Results: Numbers of patients with preeclampsia (PE) and gestational hypertension (GH) were 619 and 194, respectively. Severe cases accounted for 379 (333 for PE and 46 for GH) and mild cases accounted for 434 (286 for PE and 148 for GH). The difference in patterns of distribution of onset time between severe and mild cases of PIH was more remarkable than those between PE and GH. Discriminate analysis showed 32.3 weeks of gestation to be the optimal cut-off point at which severe forms of PIH were distinguishable from mild forms. Receiver operating characteristic (ROC) curve analysis of assumptive diagnostic efficacy for predicting severe hypertension with time of disease onset was most predictive at 32 weeks of gestation.Statistical analyses revealed that the cases presenting before 32 weeks were not significantly different from the severely hypertensive cases in terms of maternal and offspring outcomes. Comparison of PIH cases occurring after 32 weeks with cases of mild hypertension were also very similar.Conclusions: It is considered appropriate to regard 32 weeks of gestation as an optimal cut-off point for subclassification of early and late onset types of PIH.

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Timolol, a beta-blocker, has been shown to be an effective ocular hypotensive agent when used alone or with carbonic anhydrase inhibitor on ocular hypertensive or open angle glaucoma patients. The effect of timolol hemihydrate on the CO₂ hydration activities of human carbonic anhydrase (HCA) I and II and their reaction mechanisms were investigated. Timolol activates the enzyme activities of HCA I and HCA II. In HCA I and II, the enzyme kinetic results clearly showed that timolol increases the value of V_max but does not influence the value of K_m. The enzyme kinetic method showed that timolol noncompetitively activates HCA I and II activities through the formation of a ternary complex consisting of the enzyme, the substrate, and timolol. These results indicate that timolol binds apart from the narrow cavity of the active site. AutoDocking results showed that timolol binds at the entrance of the active site cavity in a region where the proton shuttle residue, His 64, of HCA I or II, is placed. The enzyme kinetic and AutoDocking results showed that timolol might weakly bind near the proton shuttle residue, His 64, to accelerate the proton transfer rate from His 64 to the buffer components. It is known that efficient activators of carbonic anhydrase possess a bulky aromatic/heterocyclic moiety and a primary/secondary amino group in their molecular structure. Timolol has a heterocyclic moiety and a secondary amino group, which are typical structures in efficient activators of carbonic anhydrase.

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The objective of the study was to make three dimensional measurements of the maxillary palate of 3- and 4-year old children who have developed anterior cross bite of deciduous dentition using a semiconductor laser. The effects of anterior cross bite were examined on the interdentition section area, the intradentition projection area, and the palate volume. Compared with normal occlusion, anterior cross bite of deciduous dentition caused smaller interdentition section areas at the deciduous canines and the primary first molars, and greater interdentition section areas at the primary second molars and between the posterior margins of the primary second molars. The intradentition projection area at the anterior dentition was smaller in anterior cross bite than in normal occlusion. The intradentition projection area at the posterior dentition in anterior cross bite was nearly the same as that in normal occlusion. The anterior palate volume was smaller and the posterior palate volume was greater in anterior cross bite than in normal occlusion. The above results suggest that anterior cross bite in deciduous dentition suppresses anterior growth and accelerates posterior growth of the maxillary palate.

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The objective of the study was to examine changes in palate sectional areas, palate projection areas and palate volumes according to age. Using the maxillary dentition models, the palates of 7-, 8- and 9-year-old children, who were in the mixed dentition period, were measured three-dimensionally using the semiconductor laser. The palate section areas, particularly between deciduous canines, primary first molars, primary second molars and first molars, increased with age, as the palate expanded vertically along with the growth and development of the maxilla. The palate projection areas increased with age, as the palate expanded laterally along with the growth and development of the maxilla. The palate volume increased with age, as the palate expanded laterally and vertically.

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The oligopeptide transporter PEPT1 (SLC15A1) is responsible for absorption of peptidic nutrients in the small intestine. Although the L-diastereomer of the β-lactam antibiotic cephalexin (L-cephalexin) is likely to be transported by PEPT1, there has been no direct demonstration of PEPT1-mediated L-cephalexin transport. Indeed, after the incubation with L-cephalexin, the intact form of L-cephalexin has not been identified inside vesicles/proteoliposomes prepared from brush border membrane of intestinal epithelial cells or cultured cell lines exogenously transfected with PEPT1 gene. Thus, it appears that L-cephalexin is rapidly metabolized by PEPT1 or PEPT1-associated proteins. Here, we attempted to verify whether L-cephalexin is transported by PEPT1 and whether it is hydrolyzed by PEPT1 itself, by using budded baculovirus expressing PEPT1 protein. Marked uptake of L-cephalexin in PEPT1-expressing budded baculovirus, compared with wild-type virus, indicated that L-cephalexin is a substrate for PEPT1. The uptake was found to be pH sensitive, and was strongly inhibited by the D-diastereomer of cephalexin and glycylsarcosine, but not by glycine. Thus, L-cephalexin is transported by PEPT1 itself. Upon the transport of both L- and D-cephalexin by PEPT1, dose-dependent membrane depolarization was observed; the EC₅₀ values of 0.18 and 2.9 mM, respectively, indicate that the affinity of L-cephalexin for PEPT1-mediated transport is much higher than that of the D-diastereomer. On the other hand, the L-cephalexin metabolite 7-aminodesacetoxycephalosporanic acid was not detected in PEPT1-expressing or wild-type virus at either pH 6.0 or 7.4. We conclude that L-cephalexin is transported by PEPT1 with high affinity, but is not metabolized by PEPT1 itself.

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Azasugars are known as potent inhibitors of glycoside hydrolases. In this study, we examined the inhibition of Cellvibrio gilvus cellobiose phosphorylase (CBP) by four azasugars (isofagomine, 1-deoxynojirimycin, castanospermine and calystegine B₂) and a non-azasugar (glucono-1,5-lactone). Isofagomine strongly inhibited CBP, whereas 1-deoxynojirimycin, castanospermine, and glucono-1,5-lactone exhibited moderate or weak inhibition. Calystegine B₂ did not inhibit CBP. Kinetic analysis in the presence of sulfate indicated that it is an extremely weak competitive inhibitor against phosphate. Moreover, crystal structures of CBP complexed with isofagomine or 1-deoxynojirimycin were determined, revealing molecular recognition of the glucosidase inhibitors by the phosphorolytic enzyme. These inhibitors are bound at subsite −1 and form several hydrogen bonds with the protein and anion (phosphate or sulfate). The strong inhibition by isofagomine is probably due to an electrostatic interaction between its endocyclic amino group and phosphate.

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β-Estradiol is conjugated by uridine 5′-diphosphate-glucuronosyltransferase (UGT) 1A to 3-glucuronide in the human liver. UGT1A has been found in the brain; therefore, UGT1A may be involved in β-estradiol 3-glucuronidation in the brain. In the present study, we aimed to characterize the β-estradiol 3-glucuronidation reaction in the rat brain. β-Estradiol 3-glucuronidation was detected in eight rat brain regions (cerebellum, frontal cortex, parietal cortex, piriform cortex, hippocampus, medulla oblongata, striatum, and thalamus). β-Estradiol 3-glucuronidation in the cerebellum was fitted to the Hill equation (S₅₀=8.0 µM, n=1.1). In inhibition experiments, β-estradiol 3-glucuronidation was inhibited to 73.6% in the cerebellum by 50 µM bilirubin, whereas it was reduced to 20.5% with 5 µM bilirubin in the liver. Unlike in the liver, Ugt1a1 may not be the main isoform catalyzing this glucuronidation in the brain. Serotonin and acetaminophen at 10 mM inhibited glucuronidation to 1.17 and 25.5%, respectively, in the cerebellum. In induction experiments, the administration of β-naphthoflavone, carbamazepine, and phenobarbital did not increase β-estradiol 3-glucuronidation in the brain except for phenobarbital in the striatum. In addition, β-estradiol 3-glucuronidation was not correlated with serotonin or acetaminophen glucuronidation in the brain, suggesting that Ugt1a6 and Ugt1a7 are not major isoforms of β-estradiol 3-glucuronidation in the rat brain. In the present study, although we were unable to identify the isoform responsible for β-estradiol 3-glucuronidation, we confirmed that β-estradiol could be metabolized to glucuronide in the brain under a different metabolic profile from that in the liver.

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Two biotic ligand models (BLMs) predicting copper accumulation and toxicity to heavy metal tolerant moss (Funaria hygrometrica Hedw.) were developed in the present study. Although BLMs developed in this study could predict the effects of pH and calcium on copper accumulation and toxicity, stability constants representing the binding strength between cations and the biotic ligand for the toxicity model were different than those for the accumulation model. Stability constants of copper, calcium and proton for the toxicity model were logK_Cu = 2.98, logK_Ca = 3.38, and logK_H = 4.17, respectively, and for the accumulation model were logK_Cu = 4.46, logK_Ca = 3.28, and no effect, respectively. Proton competition with copper accumulation was not observed. Difference in logK_Cu between the two models indicated that tolerance with copper results in the decrease in K_Cu. In addition, it was indicated that decreases in copper toxicity due to increases in proton concentration was not caused by the competitive effects of proton but by the changes in internalization flux.

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Glutathione (GSH), the most abundant intracellular thiol compound, protects various cells from metal toxicities by forming complexes with metal ions through the thiol group. γ-Glutamylcysteine (γ-EC), a glutathione precursor, is anticipated to be a functional thiol compound. However, unlike GSH, the characteristics of γ-EC in metal complex formation are largely unclear. In this study, we analyzed the ability of γ-EC to form complexes with various metal ions. 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) assays demonstrated that the reaction ratios between DTNB and γ-EC and GSH were slightly reduced by adding light metal ions, such as K⁺, Mg²⁺, and Al³⁺. These results indicated that γ-EC and GSH exhibit low thiol reactivity and weak complex formation with these ions. In contrast, the reaction ratio was reduced in a concentration-dependent manner by the addition of heavy metal ions, such as Ag⁺, Cu²⁺, Zn²⁺, and Fe³⁺. Specifically, the reaction ratio in the γ-EC-treated group was significantly reduced by the addition of Fe³⁺ compared to that in the GSH-treated group. These data indicate that, while γ-EC as well as GSH form the complexes with Ag⁺, Cu²⁺, and Zn²⁺, γ-EC has a stronger interaction with Fe³⁺ than GSH. In the proposed complex model based on the hard and soft acids and bases (HSAB) principle, GSH theoretically forms unstable nine-membered rings with Fe³⁺, whereas γ-EC can form more stable six-membered rings, resulting in a strong interaction between γ-EC and Fe³⁺.

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A mercury target vessel, composed of SUS316L stainless steel, is used for the pulsed spallation neutron source and is assembled via gas tungsten arc welding. While in operation, the target vessel suffers approximately 10⁹ loading cycles with a high strain rate of approximately 50 s^-1 because of the proton-beam-induced pressure waves in mercury. The gigacycle fatigue strength for solution annealed SUS316L stainless steels and its welded specimens were investigated through ultrasonic fatigue tests. The experimental results showed that an obvious fatigue limit was not observed at fewer than 10⁹ cycles for the base metal. In the case of no weld defects observed via penetration tests, the fatigue strength of the removed-weld-bead specimen, in which the weld lines were arranged at the center of the specimen, appeared to be slightly higher than that of the base metal. By contrast, as-welded specimens with the weld bead intact showed apparent degradation of the fatigue strength owing to the stress concentration around the weld toe.

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活性炭を用いたラドン収集器（PicoRad）は，ラドンのスクリーニングに用いられてきた。しかし，米国環境保護庁は，PicoRadを含む市販のラドン収集器について適切な測定結果が得られないことを指摘した。ラドン濃度を制御した標準ラドンチャンバで，2つのロット（有効期限が異なる） PicoRadを曝露し，その標準ラドンチャンバの基準器と比較して，計数率からラドン濃度への変換式を決定した。さらに，有効性評価を行うために，PicoRadを，ラドン濃度が制御されていないラドン場で曝露し，この変換式を用いてラドン濃度を求めたところ，ラドン濃度基準値とよく一致した。この研究では，有効期限の異なるロットごとにPicoRadの変換式の係数が必要であることが明らかになった。

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The pH dependence for the hydrolysis of β-lactam antibiotics by a metallo-β-lactamase (IMP-1) produced from Serratia marcescens was investigated varying the concentration of Zn(II). The activity of IMP-1 for imipenem was decreased at pH less than pH 5.3 without external addition of Zn(II) ions but was recovered with addition of Zn(II). Varying the concentration of external Zn(II), the molar activity of the enzyme, k_obs, that was defined by the velocity of hydrolysis of imipenem/concentration of IMP-1 was expressed by k_obs=v_init/[E]_T=k_max[Zn]/(K_d+[Zn]) in which K_d stands for the dissociation constant between Zn(II) and IMP-1. The dissociation constants, K_d, vary with pH; K_d=840×10⁻⁶ M at pH 4.3 and K_d=0.19×10⁻⁶ M at pH 6.0. The plot of −log K_d against pH showed a straight line having a slope of 4.0 below pH 5.0, showing the existence of four functional groups which may be protonated upon dissociation of Zn(II) ion(s). The k_cat, K_m, and k_cat/K_m of hydrolysis of imipenem and cephalothin in the presence of sufficient concentration of Zn(NO₃)₂ for saturation of IMP-1 with Zn(II) showed similar dependency to each other on pH between pH 6.0 and 9.0.

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We developed a stem diameter D-height H allometric model that included variability in the D-H relationship along a topographic gradient. The study site was located along a belt transect (2500 × 20 m) established in a primary tropical forest near Manaus, Brazil. The transect included typical topography of the region, characterized by plateaus and valleys called “baixios”. The D-H allometric model (n = 1307) indicated that potential tree height increased significantly, from 28 m at the lowest baixio plot to 35 m at the highest plateau plot. Consequently, by combining the D-H allometric model and an allometric equation with the variable D²H, biomass was estimated for trees (D > 10 cm) in each sub-plot (20 × 20 m). Ignoring variability in the D-H relationship introduced wide-ranging error to biomass estimation; error values ranged from -5% at a baixio plot to +6% at a plateau plot. Average biomass was 317 ± 28 (SE) Mg ha^-1, and tree density and biomass fell significantly with decreasing relative elevation.

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