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Thermokarst formation and vegetation change in central Yakutia, eastern Siberia, were reconstructed based on newly obtained AMS radiocarbon data and pollen records from four typical thermokarst depressions (alases). Radiocarbon ages of wood fragments, which are good indicators of the development of thermokarst depressions, suggest that they formed during the early Holocene. The result of dating at various locations implies that thermokarst in central Yakutia developed synchronously, at a time that regional paleoclimate records indicate warm and moist conditions prevailed. Major trends in pollen records from the four thermokarst deposits were similar. The predominant vegetation type during the thermokarst active phase was open larch and birch forest with herbaceous taxa. Grassland developed on areas exposed by a decrease in water levels of thermokarst lakes during the late Holocene.

Article, Analytical sciences. 22(9): 1261-1264 (2006)

The Holocene coastal plain of the island of Rarotonga, characterized by beach ridges and swamps, is the best developed of the Cook Islands group which lies in eastern Polynesia. Using geomorphic mapping, excavation and coring, and 14 C dating of these coastal deposits, we have reconstructed a sea-level curve and drawn maps of shoreline development for the middle to late Holocene. Our sea-level curve shows that sea level attained a position similar to that at present by 6000-6500 cal. BP, then gradually rose to a level of c. + 1.5 m above present sea level by c. 4500 cal. BP. Highstands, possibly with fluctuations to lower levels, occurred during the interval c. 4500 to c. 800-500 cal. BP. Sea level has fallen to its present level since c. 800-500 cal. BP. The sea-level curve is similar to curves obtained elsewhere in Polynesia. Hydro-isostatic movement may have been responsible for the relative sea-level change before c. 800-500 cal. BP, whereas the sea-level fall since then is in agreement with records from western Polynesia that attribute such a fall to climatic change. The coastal plain of Rarotonga began to emerge c. 4500 cal. BP, and prograded to the present coastline, most conspicuously on the northeastern coast. The formation of such a flat area on the coast associated with these mid- to late Holocene shoreline developments is likely to have influenced the pattern of human settlement in Rarotonga.

Background Plasma PAF-acetylhydrolase (PAF-AH) gene polymorphisms (G994 → T in exon 9) and the resulting deficiency of enzyme activity were identified in the Japanese population. The objective of this study was to assess the joint effect of the polymorphism and hypercholesterolemia on risk of atherosclerosis. Methods and Results We performed a case-control study including 150 patients who underwent operation for peripheral arterial occlusive disease (PAOD) and 158 controls matched for age and sex. Genomic DNA was analyzed for the mutant allele by a specific polymerase-chain reaction. Plasma PAF-AH activity was measured in both groups. The patients with multiple atherosclerotic diseases showed higher levels of PAF-AH activities than the patients with only peripheral artery occlusive disease among normal genotypes. PAOD patients were assessed either with or without polymorphism or hypercholesterolemia in regard to accompanying coronary artery disease or stroke. The prevalence of the polymorphism was significantly more frequent in the patients with PAOD. The plasma PAF-AH activity was correlated with total cholesterol and LDL level, and inversely related with HDL in normal genotype (GG) PAOD patients. However, neither the correlation nor the inverse relation was found in patients with the polymorphism. Patients with both hypercholesterolemia and the polymorphisms revealed a relative risk for other atherosclerotic disease of 11.5 (6.0-40.3) compared with normal genotype and normal lipid level. Conclusion The plasma PAF-AH gene polymorphism and hypercholesterolemia may interact and increase the risk of atherosclerosis.

Detailed depth profiles of photosynthetic pigments in a sediment core (G-12) collected at the BDP93 site, the Buguldeika saddle, of south Lake Baikal, along with depth profiles of total organic carbon (TOC) and biogenic silica, were studied to elucidate the temporal changes of phytoplankton assemblages in the lake during the past 28 kyr. In addition to the quantification of carotenoids by high-performance liquid chromatography with photodiode-array detection (HPLC-PDA), steryl chlorin esters (SCEs) were analyzed by HPLC-PDA, HPLC-mass spectrometry (LC-MS) and sterols in SCEs by gas chromatography–mass spectrometry (GC–MS) to enrich the taxonomical information on the phytoplankton composition. Allochthonous input of organic matter from the Selenga River resulted in the higher TOC contents in core G-12 than in a previously reported core (G-6) collected at another site from the southern basin. The poorer correlation in core G-12 than in G-6 between TOC and chlorophyll-a-originating pigments, which are indicative of autochthonous production, also indicated a significant allochthonous input at the site. The abundance of lutein among the carotenoids detected, and the good correlation of total chlorophyll a and b shows that green algae represented a significant portion of the phytoplankton, accompanying the diatoms at the G-12 site, after the last glacial period. The presence of cryptomonads and cyanobacteria were confirmed from marker carotenoids in the sediment core. GC–MS analysis of sterols in SCEs detected marker sterols of diatoms, green algae, chrysophytes and dinoflagellates. The depth profiles of the measured indicators gave consistent features for temporal changes in phytoplankton assemblage at the G-12 site of Lake Baikal after the last glacial maximum.

Fiber-reinforced composite laminates are often used in severe environments such as high temperature and humidity conditions. Therefore, it is of practical interest to establish a simple but robust method to determine material properties that define the hygrothermal behavior of composites under various conditions. In this article a novel inverse analysis approach is presented to identify the diffusivity, maximum moisture content, and coefficient of thermal expansion (CTE) and coefficient of moisture expansion (CME) of carbon fiber-reinforced epoxy matrix composites subjected to various conditions of environmental exposure. This procedure involves three distinct steps. First, the transient expansions and weight gains are experimentally measured under different temperatures and humidity conditions. Next, reference solutions are established from detailed computational models, which incorporate the heterogeneous nature of composite's microstructure. Finally, the Kalman filter technique is utilized to extract best estimates of the material parameters of interest. The use of inverse analysis is necessitated by the fact that backward relations from the measured parameters to the unknown properties are not directly apparent. The results show diffusivity to be a strong function of temperature while the maximum moisture content to be a strong function of relative humidity. For the case of material expansion, moisture induced strains as well as thermal strains exhibit slight dependence on temperature. In addition to estimating the material parameters of interest, detailed studies are conducted to investigate the source of scatterings observed in the expansion measurements during heating and moisture absorption, and possible 3D effects in measurements.

Horse heart cytochrome c (cyt c) was adsorbed on the binary self-assembled monolayers (SAMs) composed of thioctic acid (T-COOH) and thioctic amide (T-NH2) at gold electrodes via electrostatic interaction. The cyt c adsorbed on the modified gold electrode exhibited well-defined reversible electrochemical behavior in 10 mM phosphate buffer solution (PBS, pH 7.0). The surface concentration (Γ) of electroactive species, cyt c, on the binary SAMs was higher than that in single-component SAMs of T-COOH, and reached a maximum value of 9.2 × 10−12 mol cm−2 when the ratio of T-COOH to T-NH2 in adsorption solution was of 3:2, and the formal potential (E0′=(Epa+Epc)/2)(E0′=(Epa+Epc)/2) of cyt c was −0.032 V (vs. Ag|AgCl (3 M NaCl)) in a 10 mM PBS. The interaction between cyt c and the binary SAMs made the E0′E0′ shift negatively when compared with that of cyt c in solution (+0.258 V vs. NHE, i.e., +0.058 V vs. Ag|AgCl (3 M NaCl)). The fractional coverage of bound cyt c was a 0.64 theoretical monolayer. The standard electron transfer rate constant of cyt c immobilized on the binary SAMs was also higher than that on single-component SAMs of T-COOH, and the maximum value of 15.8 ± 0.6 s−1 was obtained when the ratio of T-COOH to T-NH2 in adsorption solution was at 3:2. The results suggest that the electrode modified with the binary SAMs functions better than the electrode modified with single-component SAMs of T-COOH.

Two sediment cores recovered in the central part of Daihai Lake in north-central China were analysed at 2-to 4-cm intervals for total inorganic and organic carbon (TIC and TOC) concentrations. The TIC concentration is inferred to reflect temperatures over the lake region and an increase in the TIC concentration implies an increase in the temperature. TOC concentration is considered to reflect the precipitation in the lake basin and higher TOC concentrations denote more precipitations. Thus AMS 14C time series of the TIC and TOC records of Daihai Lake sediments uncovers a detailed history of changes in temperature and precipitation in north-central China during the last c. 12 000 yr. The Holocene, an epoch of postglacial warmth, started c. 11 500 cal. yr BP, and can be subdivided into three stages: the early (c. 11 500-8100 cal. yr BP), middle (c. 8100-3300 cal. yr BP) and the late Holocene (c. 3300-0 cal. yr BP). The climate was warm and dry during the early Holocene, warm and wet during the middle Holocene, and in the late Holocene became cooler and drier but displayed a relatively warmer and wetter interval between c. 1700 and 1300 cal. yr BP. The Holocene Climatic Optimum, defined as a postglacial episode of both megathermal and megahumid climate, might have occurred in north-central China between c. 8100 and 3300 cal. yr BP, and the climate during this period was variable and punctuated by cool and/or dry events. We infer that changes in the temperature were directly controlled by changes in summer solar radiation in the Northern Hemisphere resulting from progressive changes in the Earth's orbital parameters. Whereas an increase in the monsoonal precipitation could be closely related to an increase in the sea surface temperature of the low-latitude Pacific Ocean, an increase in the temperature and size of the Western Pacific Warm Pool and a westward shifted and strengthened Kuroshio Current in the western Pacific.

Fiber-reinforced composite laminates are often used in harsh environments that may affect their long-term durability as well as residual strength. In general, environmental degradation is observed as matrix cracking and erosion that leads to deterioration of matrix-dominated properties. In this work, cross-ply laminates of carbon fiber reinforced epoxy were subjected to environmental degradation using controlled ultraviolet radiation (UV) and moisture condensation and the post-exposure mechanical properties were evaluated through elastic modulus and failure strength measurements. Additionally, both degraded and undegraded were subjected to cyclic fatigue loading to investigate possible synergistic effects between environmental degradation and mechanical fatigue. Experimental results show that the degradation results in reduced failure strength. Greater effects of degradation are observed when the materials are tested under flexural as opposed to uniaxial loading. Based on strength measurements and scanning electron microscopy, we identified various damage modes resulting from exposure to UV radiation and moisture condensation, and cyclic loading. The principal mechanisms that lead to reduction in mechanical properties are the loss of fiber confinement due to matrix erosion, due to UV radiation and moisture condensation, and weakened/cracked ply interfaces due to mechanical fatigue. An empirical relationship was established to quantify the specific influence of different damage mechanisms and to clarify the effects of various degradation conditions.

OBJECTIVE The purposes of this study were to assess the clinical features of cardiac auscultatory events in outpatients in general internal medicine, and to make teaching suggestions for education on cardiac auscultatory skills in primary care medicine. METHODS The subjects included 104 consecutive outpatients with chest symptoms, and cardiac auscultatory findings were assessed prospectively. RESULTS Cardiac auscultatory events were found in 32 (30.8%) among the 104 subjects. The subjects with cardiac auscultatory events were significantly older than those without cardiac auscultatory events (p < 0.05). The cardiac auscultatory events of the 32 subjects were as follows; splitting of the first heart sound in 2 subjects, mid-systolic click in 2 subjects, fourth heart sound in 3 subjects, systolic murmur in 24 subjects (including one subject with both systolic and diastolic murmurs), and diastolic murmur in 2 subjects. Aortic stenosis was diagnosed in 2 subjects, and mitral regurgitation was diagnosed in one subject of the 24 subjects with a systolic murmur. One subject with both systolic and diastolic murmurs was considered to have a relative systolic murmur with aortic regurgitation. The other 20 subjects with a systolic murmur were considered to have innocent murmurs. The 2 subjects with a diastolic murmur were diagnosed as having aortic regurgitation. CONCLUSIONS We suggest that the following cardiac ausculatory events should be given educational priority in primary care; 1) Fourth heart sounds as an extra heart sound. 2) Innocent murmurs : characteristics of innocent murmurs and discrimination from systolic murmurs caused by organic heart disease. 3) Systolic murmurs caused by aortic stenosis or mitral regurgitation. 4) Diastolic high-pitched murmurs caused by aortic regurgitation.

今回われわれは31歳の女性で右鼠径部の痛みと腫脹を主訴に受診し,緊急手術を行い子宮円索血栓性静脈瘤と診断した1例を報告する. 腫瘤は妊娠20週に現れ,正常分娩4日後に,急速に増大して,落痛が出現した.鼠径ヘルニア嵌頓を疑い,緊急手術を施行した.術中に血栓性静脈瘤を鼠径管内に認めた.妊娠後期・産褥期の鼠径部腫脹,痔痛などの症状がみられた場合,子宮円索血栓性静脈瘤は念頭に置く必要があると思われる.

Background: The purpose of this study was to assess the left ventricular (LV) diastolic function in elderly patients with aortic stenosis (AS). Methods: The subjects included 11 consecutive elderly patients with AS (AS group), and 17 elderly patients with hypertensive LV hypertrophy (HT group), all were more than 70 years of age. Echocardiographic and Doppler examinations were performed, and the data was analyzed to determine the LV end-diastolic dimension (LVDd), the LV mass index (LVMI), fractional fiber shortening (FS), the aortic valve resistance (AVR), peak aortic flow velocity (peak V), and the maximal early diastolic transmitral flow velocity (E). The flow propagation velocity (FPV) was measured during early LV filling phase using a color M-mode Doppler method. Then, (i) FPV/E were compared between the two groups; and (ii) correlations between FPV/E and LVMI, LVDd, AVR, and FS/peak V were assessed in the AS group. Results: FPV/E was significantly lower in the AS group than in the HT group (P < 0.01). There were significant negative correlations between FPV/E and LVMI (r =−0.728, P

A pre-industrial iron-smelting site in Korea, whose period of active use is placed on typological grounds between the eighth and 18th centuries AD, has been dated using accelerator mass spectrometry and thermoluminescence. The ages of two charcoal samples were 77 ′ 25 and 81 ′ 25 years BP, with the calibrated date for both ranging from AD 1700 to AD 1955, while a clay fragment dated to AD 1650 ′ 50. The results from typology and radiocarbon seem insignificant due to the considerable uncertainties involved, but in combination with the thermoluminescence result they place the most probable date of the site at around AD 1700.

In measuring radiocarbon ages of fossil bone samples, it is necessary to extract pure bone protein from the samples by chemical treatment. To evaluate the effect of the chemical treatment including XAD-2 chromatography on carbon and nitrogen isotopic values, we measured C / N ratio, δ 13 C and δ 15 N in decalcified fraction, gelatin, hydrolysate, and XAD-treated hydrolysate extracted from fossil bones together with modern samples. The C / N ratios of the collagen fractions progressively decreased as chemical treatment proceeded. The δ 13 C values of the fractions became more positive as purification proceeded. There was an overall + 0.5∼+ 2.0‰ difference in δ 13 C and a slight trend of decrease in δ 15 N during chemical processing and around + 0.3‰ difference in δ 13 C and + 0.2‰ in δ 15 N during XAD-2 treatment only. The large change in C / N ratio and δ 13 C of the hydrolysates following XAD-2 chromatography in the Bovine Achilles tendon collagen standard could be explained by the removal of lipids unextracted before the XAD-2 treatment. There was no difference in δ 13 C between hydrolysates and XAD-treated hydrolysates in fossil bones because the latter contains negligible preserved lipids. Fossil bones and lipid-extracted collagen standard showed the similar C / N change and isotopic fractionation during sequential chemical treatment. Individual amino acid standards showed little to no increase in δ 13 C and δ 15 N values during XAD-2 treatment, except for aspartic acid and glutamic acid, which showed pronounced increase in δ 15 N values. Furthermore, regarding amino acid compositions separated by XAD-2 treatment, alanine and glycine tend to be enriched, while valine, threonine, isoleucine, leucine, and serine compositions tend to be depleted. The carbon and nitrogen isotopic fractionation during sequential chemical treatment might reflect variation in the amino acid composition of the extracted fractions due to degradation, such as decarboxylation, rather than removal of contaminants. The variation during XAD-2 treatment is due to both degradation by HCl and isotopic fractionation related to the XAD-2 resin.

We analyzed photosynthetic pigments, total organic carbon (TOC) and total nitrogen (TN) in two radiocarbon-dated sediment cores of Lake Hovsgol, NW Mongolia, covering the period of the last glacial/post-glacial transition since 23 14C ka. The sedimentary profiles of total chlorophyll-a derivatives (TChl-a), TOC and TN reflect productivity increase during the last glacial/post-glacial transition between 15 and 10 14C ka in response to regional climate warming and enhanced precipitation. Correlation between TChl-a and TOC was high ( R 2 = 0.934 , n = 74 ) with a zero intercept of a regression line suggests that total organic carbon in Lake Hovsgol sediments is of autochthonous origin. The depth profiles of TOC/TN ratio showed increases toward the core top in parallel with other paleoproductivity proxies, serving as an indicator of climatic transition, quite similar to Lake Baikal sedimentary record. The primary reason for the shifts of this parameter is still not clear, however. Chlorophyll-b derivatives and some algal carotenoids such as lutein, zeaxanthin diatoxanthin and canthxanthin, were detected, although in concentrations lower than that of TChl-a. These biomarkers indicate that green algae, cyanobacteria and diatoms were present in phytoplankton during the post-glacial period, significantly pre-dating the beginning of the Holocene. Abrupt drops of biomarker profiles at ca. 1–2 and 10 14C ka due to decreased productivity in the lake or enhanced degradation of the biomarkers likely record short-term climatic events.

Two sediment cores recovered in the central part of Daihai Lake in north-central China were analysed at 2- to 4-cm intervals for grain-size distribution. Grain-size distributions of the lake sediments are inferred to be a proxy for past changes in East Asian monsoon precipitation, such that greater silt-size percentage and higher median grain size reflect increased monsoonal precipitation rates. The grain-size record of Daihai Lake sediments spanning the last ca 10,000 yr indicates that the monsoonal precipitation in the lake region can be divided into three stages: the Early, Middle and Late Holocene. During the Early Holocene before ca 7900 cal yr BP, the median grain size (Md) and the silt-fraction content were relatively low and constant, suggesting relatively low precipitation over the lake region. The Middle Holocene between ca 7900 and 3100 cal yr BP was marked by intensified and highly variable monsoonal precipitation, as indicated by high and variable Md values and silt contents of the lake sediments. During this period, average precipitation rate gradually increased from ca 7900 to 6900 cal yr BP, displayed intense oscillations between ca 6900 and 4400 cal yr BP, and exhibited a decreasing trend while fluctuating from ca 4400 to 3100 cal yr BP. Although generally high during the Middle Holocene, both the Md and the silt content assumed distinctly low values at the short intervals of ca 6500–6400, 6000–5900, 5700–5600, 4400–4200 cal yr BP, implying that monsoonal precipitation might have been significantly reduced during these intervals. During the Late Holocene since ca 3100 cal yr BP, grain-size values suggest that precipitation decreased. However, during the Late Holocene, relatively higher Md values and silt contents occurring between ca 1700 to 1000 cal yr BP may denote an intensification of hydrological cycles in the lake area. Changes in the East Asian monsoonal precipitation were not only directly linked with the changing seasonality of solar insolation resulting from progressive changes in the Earth's orbital parameters, but also may have been closely related to variations in the temperature and size of the Western Pacific Warm Pool, in the intensity of the El Nino–Southern Oscillation, and in the path and strength of the North Equatorial Current in the western Pacific.

The electrochemical behavior of a poly(acrylamide) (PAA) membrane electrode (ME), in which the PAA works as a membrane matrix for use in non-aqueous solutions, was investigated in acetonitrile. It was found that PAA MEs possess properties of microelectrode ensembles (MEEs). For the thin PAA membrane, the electrode behaved similar to a macroelectrode and peak-shaped voltammograms were achieved at low scan rates, while at high scan rates the electrode acted as a microelectrode and sigmoidal-shaped voltammograms were obtained. For the thick PAA membrane electrode, however, voltammograms were sigmoidal-shaped at low scan rates, and at high scan rates the voltammograms became peak-shaped again. Quantitative and semiquantitative analyses of the electrochemical response characteristics of these ensembles were conducted. The results show that the electrochemical behavior of these ensembles is in close agreement with the predictions of established microwell electrochemical theory.

The integrity of a composite laminate can be greatly affected by an existence of embedded interlaminar flaw. In general, identification of such a flaw often requires expensive tools and tedious processes. The aim of the present work is to develop a novel method with the aid of an intelligent post-processing scheme, thereby not relying on those sophisticated experiments. Essentially the proposed procedure utilizes an inverse analysis to estimate unknown delamination parameters from limited measurements. The procedure first constructs approximate functions relating the delamination parameters to measurement parameters. Then, a multi-dimensional minimization technique is adopted to search for the best estimates of unknown parameters corresponding to the lowest value of error objective function. In the present verification and simulation analyses, surface strains at discrete locations on a composite laminate under three-point bending are selected as the input measurements. Although reasonable estimates are obtained with these measurements, to increase their accuracy, the deflection at load point is also included as measurement input. Additional improvements are observed when those measurements under multiple loading conditions are included. A detailed error sensitivity analysis is also carried out to confirm the method’s robustness. These results suggest the current method to be one of the alternate identification approaches for detecting a single embedded delamination in composite laminates.

今回われわれは直腸癌術後孤立性脳転移に対し腫瘍摘出術および術後照射を施行し,6年3カ月の無再発長期生存例を経験したので報告する.症例は68歳,男性.平成6年8月直腸癌と診断され腹会陰式直腸切断術を施行した.病理組織学的検査では,直腸Rb,腫瘍径は5.0×6.5cm,中分化腺癌,mp,n0,H0,P0,M(-),stage Iであった.平成10年7月頃より失語症,右不全麻痺を認め,脳腫瘍を指摘された.平成10年8月19日脳腫瘍全摘術施行.腫瘍は2.5×1.5cm,組織学的には中分化腺癌であり,直腸癌の脳転移と診断した.術後定位脳放射線治療(50Gy/25回)を施行.直腸癌術後10年3カ月,転移性脳腫瘍術後6年3カ月の現在無再発生存中である.

症例は59歳,女性. 7年前左乳癌にて乳房切除術を受け当院でフォローされていた. 3年半前腹部膨満を自覚して腹部CTが施行され,脾周囲および脾内部に低吸収域を認め,脾嚢胞と診断された.手術は拒否していたが,腹部愁訴が強くなってきたので手術の同意を得た.手術所見では,脾周囲にはゼリー状黄色透明の液体が大量に貯留し,腹腔内全域にも同様の粘液貯留を認めて,腹膜偽粘液腫と診断された.虫垂に硬い腫瘤と粘液腫を認め,虫垂,大網,脾臓を摘出した.病理組織学的検査で,虫垂に粘液嚢胞腺癌,脾内部の粘液貯留部に上皮細胞を認め,腹膜偽粘液腫が脾内部に転移したものと考えられた.術後8カ月の現在, CT上再発なく, CEAも正常化している.脾転移をきたした腹膜偽粘液腫は極めて稀で,医学中央雑誌で検索しえた限り, 10例のみであった.

In order to trace the changes in the activity of ions in dipolar aprotic solvents, poly(acrylamide) membrane based ion selective electrodes were developed in the author's laboratory. This review covers (1) the development of the electrodes, including the synthesis of host compound modified poly(acrylamide); (2) potentiometric response properties of the electrodes; (3) investigations of the response mechanism by means of spectrophotometric and cyclic voltammetric methods; and (4) applications to determine the solubility products of slightly soluble electrolytes in dipolar aprotic solvents, successive complex formation constants of ions with some dipolar aprotic solvent molecules, and standard molar Gibbs energies of ions transfer.

Noble gas, Nd and Sr isotopic ratios and major and trace element compositions were determined for ultramafic xenoliths and their host Cenozoic alkali basalts from Baegdusan, Baegryongdo, Jogokri, Jejudo in the Korean peninsula, and Long Quan, close to the Baegdusan in northeastern China, to characterize the lithospheric mantle and the source of alkali basaltic magmatism beneath the active continental margin of the southeastern part of the Eurasian plate. The xenolith samples yield significantly variable 3He/4He ratios ranging from

The effects of pore sizes, shapes, and orientations on the mechanical properties of thermally sprayed ceramic coatings are investigated. The analysis is conducted using detailed finite-element models with geometries similar to those of actual ceramic coatings containing many embedded pores. These microstructural models include many randomly placed pores of different sizes and shapes and are loaded in tension to determine their effective elastic moduli along the spray and transverse directions. We modeled coatings with statistical distributions of pore sizes and shapes that followed those of actual Al2O3–TiO2 coatings. Because the pores in such a model are of different sizes and shapes, the model must be large enough to contain sufficient pores before the average modulus obtained from uniaxial loading can be identified as an effective property. Using differently sized models, we determined the variability of the average moduli. Such information is valuable when homogenized or continuum material models are used in the stress analyses of coatings. Our computed results show that a model must be large enough to contain 50–100 pores before the averaging of properties is accurate. Using the Al2O3–TiO2 models, we also simulated microindentation tests. Unlike the results determined from uniaxial loading, the elastic moduli estimated from indentation possessed large variations. Apparently, the morphology of the pores immediately beneath the indentation or within the zone of influence has a significant effect on the response of the indenter and the measured modulus. The implications of these results and the computational capability to predict the mechanical properties of porous, plasma-sprayed ceramic coatings are discussed here.

Modifying electrode surfaces on the molecule scale allow developing new electrochemical biosensors. A new strategy for the immobilization of calf thymus DNA on the surface of gold nanoparticles which are co-immobilized at a gold electrode through 4,4′-bis(methanethiol) biphenyl (MTP) molecule by assembly process is demonstrated. The DNA modified electrode was incubated in Co(phen)33+ solution of an aqueous buffer or an acetonitrile (AN) solution, then it was rinsed and placed in a Co(phen)33+ free buffer solution or AN solution, followed by cyclic voltammetric experiments. Clear redox peaks of Co(phen)33+ were observed both in an aqueous and AN solutions. The concentration of supporting electrolyte on electrochemical behavior was discussed. It was found that the surface coverage value of DNA molecules on modified gold nanoparticle and the redox current of adsorbed Co(phen)33+ were decrease with increasing the size of gold nanoparticles (6, 25, 42, 73, and 93 nm). In aqueous solution, the electron transfer rate constant of Co(phen)33+/2+ redox couple became slow with increasing the diameter of gold nanoparticle, and the speed almost had nothing to do with the diameter in nonaqueous solution. The surface concentration of Co(phen)33+ adsorption on DNA modified electrode decreased and rate constant of adsorption kinetics increased with increasing the interactive temperature. In AN solution, the electrostatic interaction between DNA and Co(phen)33+/2+ was greatly reduced, however, compare with in aqueous solution the interaction between DNA and reduced form of Co(phen)32+ was more strongly than oxidized form Co(phen)33+. The surface concentration of Co(phen)33+ adsorption on DNA modified electrode reach maximum value when the interactive temperature about 20 °C, and rate constant of adsorption kinetics nearly independent of the interactive temperature. The results show that the DNA can adsorb on the modified electrode firmly and the Co(phen)33+/2+ adsorbed on DNA give good electrochemical response both in aqueous and nonaqueous solutions. It was confirmed that the DNA modified electrode can be applied in a nonaqueous system and the modified electrode can be used to investigate the interaction between DNA and electroactive species both in aqueous and nonaqueous systems.

Improvement of the physical properties of pyrazole derivative 1, which we reported previously as a potent and selective 20-HETE synthase inhibitor (IC(50) 5.7 nM), is described. Introduction of a sufficient substituted-amino group on the side chain enhanced the water-solubility of 1 (0.014 mg/mL at pH 6.8). Among the products, 2-piperazinoethoxy derivatives 3e and 6b showed solubility suitable for injection and potent inhibitory activity toward 20-HETE synthase (IC(50) 21.2 and 14.0 nM, respectively).

Article, ANALYTICA CHIMICA ACTA. 525(1): 105-110 (2004)

This paper presents the features of the “eleven-year” cycle of radiocarbon content during the period of prolonged sunspot minimum called the Maunder Minimum (1645–1715 AD). Whether or not the Sun had maintained the cyclic polarity reversal even during the Maunder Minimum has been a controversial topic for a long time. Although persistency of the cyclicity has been investigated by using cosmogenic isotopes or by calculations, a consistent description has not been obtained so far. Hence, we have obtained a new record of carbon-14 content in tree rings from 1631–1739 AD, and made a comparison with the record previously obtained. Periods of 13–15 and 24–29 years detected in the variation of carbon-14 content seem to be suggesting that the Sun had retained periodic polarity reversal during this prolonged minimum with slightly longer periodicity than that of recent intense solar activity. Our results seem to support the inverse correlation between the intensity and the cycle length of solar activity.

We examined different concentrations of HCl, such as 0.4, 0.6, 0.8, 1.0 and 1.2 M, for decalcification of fossil bones and different times of 0.1 M NaOH treatment on collagens to determine the best conditions for purifying collagen through extraction of humic contaminants, and compared the alkali treatment method with the XAD-2 treatment method for several types of fossils. The yield of acid-insoluble bone fractions did not change over the range from 0.4 to 1.0 M HCl and decreased suddenly with 1.2 M HCl on decalcification, and the 14C ages of the extracted gelatins from the five decalcified fractions were unchanged, suggesting that

In 1996/1997, a 14 C-AMS system (model 4130-AMS) manufactured by High Voltage Engineering Europe (HVEE), B.V., The Netherlands, was installed at the Center for Chronological Research (CCR), Nagoya University. The system provides highly precise and accurate 14 C determinations as well as δ 13 C values for graphite targets (1.5 mg carbon and 3 mg iron powder) prepared from standards and samples. One sigma errors in 14 C ages typically range from ±20 to ±40 yr for materials younger than 8000 BP, depending on absolute 14 C ages or 14 C counting uncertainties. Standard deviations of 13 C/ 12 C ratios range from ±0.1‰ to ±0.9‰. For relatively young samples, accuracies of less than 10‰ are obtained using IAEA reference materials and FIRI test samples. Background levels on the 14 C-AMS system range from 52 to 54 ka BP for a pure graphite powder. The HVEE 14 C-AMS system at the CCR has been used routinely to date samples with a variety of research applications.

Recently radiocarbon (14C) concentration in the atmospheric CO2 has decreased over time due to the exchange of CO2 between atmosphere and ocean, but also due to emission of 14C free-CO2 from burning fossil fuels. The second contribution, known as the Suess effect, can be observed in the highly industrialized and/or urban area. 14C concentrations in annual rings of a pine tree from the urban area in Nagoya, Japan, that grew over the last 24 years were measured with AMS to be remarkably lower than those observed in “clear air” of corresponding years at Schauinsland station in Germany. The measured data were used to estimate the rate of the fossil component in atmospheric CO2 that was derived from fossil fuel burning. Exponential and linear functions were fitted to the secular variations of 14C concentration in annual rings to calculate the decay constant and an average decreasing rate of 14C concentration. The result suggests that the use of annual rings of trees to obtain the secular variations of 14C concentration of atmospheric CO2 can be useful and efficient for environmental monitoring and modeling of the carbon distribution in local scale.

A method using carbon isotopes (14C and 13C) for quantifying the proportion of CO2 contribution from deep sources, e.g. magma, subducted materials or mantle, in soil air is established, and discussed in comparison with the conventional methods and errors. A relationship between carbon isotopic ratios ( δ 14 C and δ 13 C ) and CO2 concentration has been used to estimate proportions of CO2 reservoirs in conventional studies. Our study indicates that a relationship between δ 14 C and δ 13 C is available to quantify the CO2 derived from deep subsurface, deep CO2 contribution, within low errors (1σ=0.01–0.02). The estimated values of deep CO2 contribution by this method were agree with those estimated by the conventional method, while the estimated results using the relationship between δ 13 C and CO2 concentration show slightly higher values of deep CO2 contribution than those by the method using the δ 14 C in several samples. The quantifying errors estimated by δ 14 C and CO2 concentration are the smallest to be ca. ±0.005, but in case of the CO2 concentration higher than 1% in soil air. With regard to the method using δ 13 C and concentration, the error of estimated results shows ca. ±0.05 for the sample of which CO2 concentration is over 2%.

DH99a sediment core recovered at the center of Daihai Lake in north-central China was analyzed at 4-cm intervals for pollen assemblage and concentration. The pollen record spanning the last ca 10,000 yr revealed a detailed history of vegetation and climate changes over the Daihai Lake region during the Holocene. From ca 10,250 to 7900 cal yr BP, arid herbs and shrubs dominated the lake basin in company with patches of mixed pine and broadleaved forests, indicating a mild and dry climatic condition. Over this period, the woody plants displayed an increasing trend, which may suggest a gradual increase in warmth and humidity. The period between ca 7900 and 4450 cal yr BP exhibits large-scale covers of mixed coniferous and broadleaved forests, marking a warm and humid climate. Changes in the composition of the forests indicate that both temperature and precipitation displayed obvious fluctuations during this period, i.e., cool and humid ca 7900– 7250 cal yr BP, warm and slightly humid ca 7250– 6050 cal yr BP, warm and humid between ca 6050 and 5100 cal yr BP, mild and slightly humid ca 5100– 4800 cal yr BP, and mild and humid ca 4800– 4450 cal yr BP. The period can be viewed as the Holocene optimum (characterized by a warm and moist climate) of north-central China, with the maximum (dominated both by warmest temperatures and by richest precipitations) occurring from ca 6050 to 5100 cal yr BP. During the period of ca 4450– 2900 cal yr BP, the woody plants declined, and the climate generally became cooler and drier than the preceding period. This period is characterized by a cold, dry episode from ca 4450 to 3950 cal yr BP, a warm, slightly humid interval between ca 3950 and 3500 cal yr BP and a mild, slightly dry episode from ca 3500 to 2900 cal yr BP, and appears to be a transition from warm and humid to cold and dry climatic conditions. Since ca 2900 cal yr ago, the forests disappeared and the vegetation density decreased, reflecting a cool and dry climate. However, a relative recovery of the woody plants occurring between ca 1700 and 1350 cal yr BP may denote an increase both in temperature and in precipitation. Fluctuations in the climatic condition of the Daihai Lake region were not only related to changes in the seasonal distribution of solar insolation and in the axis and intensity of the ocean current in the western North Pacific but were also closely linked to variations in the position and strength of polar high-pressure systems and in the pattern and intensity of the Westerly winds.

This paper introduces a criterion suitable for the simulation of crack propagation in elastic–plastic graded materials. It proposes a power-law relationship between the two critical failure parameters, surface separation energy and peak separation stress, which are spatial variants in graded solids. To investigate its feasibility, this criterion is implemented in finite element models and tested under various dynamic failure conditions. First, dynamic crack propagation in double cantilever beam model is considered and the effects of the failure parameters are investigated. The results show crack propagation behavior is highly dependent on the variations of the failure parameters. Evolutions of various energy components are also monitored during the crack growth to evaluate failure characteristics of graded materials. Unlike homogeneous materials, crack propagation in elastic–plastic graded materials never attains a steady state and the fracture energy associated with crack growth continues to vary as the crack propagates through the graded region. In a subsequent analysis, impact failure of a ceramic–metal graded layer is considered. In this case, multiple crack initiate and propagate at various locations. Additionally, different through-thickness compositional gradations are examined to study their effects on cracking profiles and energy absorption characteristics. It is demonstrated that the cracking substantially alters the overall pattern of energy evolutions even though the energy directly consumed by the surface separations remains small. This study concludes that similar approaches can be employed for investigating failure in other inhomogeneous/heterogeneous materials to optimize their design.

Accurate crack propagation simulation requires critical fracture parameters to be known a priori. For elastic-plastic materials, two fundamental parameters are the separation energy and the peak stress required to generate new crack surfaces. In general, both are difficult to quantify since direct determinations are not possible in experiments. For inhomogeneous materials, such as graded materials, determination is even more complex since these parameters vary spatially. In this paper, a novel method based on an inverse analysis technique is proposed to estimate the fracture parameters of elastic-plastic and graded media. The method utilizes the Kalman filter to process measured data and extract best estimates of the unknown parameters. The accuracy of the method is examined in a verification study where a dynamically propagating crack in double cantilever beam type specimen is modeled. In the study, time variation records of crack opening displacement, opening strain, crack advance distance, and load point reaction force are used as possible measurements. Despite large noises in data, the results confirm accurate estimation. The estimates improve when multiple measurements are supplied to the inverse technique.

Detailed three-dimensional finite element analysis was carried out for area-array solder-bumped flip-chip packages. The analysis enabled determinations of accurate three-dimensional effects on stress distributions as well as local fracture behaviors under thermal load. The 3D analysis also estimated thermal fatigue life of solder bumps. Since dimensions of various components span more than three orders of magnitude, the multi-scale finite element models were utilized to elucidate detailed deformation state near solder bumps. The global-local approach identified of critical solder bumps due to the overall deformation and investigated of interfacial delamination at microstructural level. The local model contained a single solder bump and sub-micron UBM layers. The two-step modeling approach enabled accurate fracture analysis otherwise difficult in large 3D models. Our analysis found the crack driving force and preferred delamination direction based on the 3D J -integral calculations. Shear deformations within and surrounding solder bump connectors were also investigated. The results revealed higher deformation in the 3D model than those predicted from 2D models. Additionally, the strain components were different. This has an important implication on the plastic flow characteristics during cyclic loading. Our model estimated about 25% greater steady-state shear strains in the 3D model than those in the 2D models. This result suggests a much shorter fatigue life than that based on the 2D analysis.

Evidence suggests that the erythropoietin-producing hepatocellular (EPH) receptor tyrosine kinases (RTKs) and their ephrin (EFN) ligands are involved in human carcinogenesis. Expression of two of them, EFNA1 ligand and its receptor, EPHA2, has been proposed to contribute to tumor-induced neovascularization. Colorectal cancers were examined for expressions of EPHA2 and its ligand EFNA1 by semi-quantitative RT-PCR, and double-immunostained for EPHA2 and CD34. Microvessels in the tumors were counted. Double-staining was also performed in 25 cases of adenoma with focal cancer for comparison. Trends of overexpression of both EPHA2 and EFNA1 was found in tumor tissue compared to the corresponding normal tissue in the same specimen [22/37 (59.5%) and 25/37 (67.5%), respectively; P = 0.100 for EPHA2 and P = 0.009 for EFNA1]. Overexpression of EPHA2 and EFNA1 was noted more frequently in the early stage than in the late stage [EPHA2, 15/21 (71.4%) vs. 7/16 (43.8%), P = 0.007; EFNA1, 15/21 (71.4%) vs. 10/16 (62.5%), P = 0.007]. Both EPHA2 and EFNA1 were more frequently overexpressed in smaller tumors (less than 5 cm) than in larger tumors [EPHA2, 15/21 (71.4%) vs. 7/16 (43.8%), P = 0.017; EFNA1, 16/21 (76.2%) vs. 8/16 (50%), P = 0.001]. Tumors less than 5 cm in diameter and in stages I and II were significantly more likely to overexpress EPHA2 and EFNA1 (P = 0.001 for EPHA2, P = 0.001 for EFNA1). Microvessel counts (MVCs) after immunostaining for CD34 were significantly correlated (r = 0.343, P = 0.037) with overexpression of EPHA2. EPHA2-expressing focal cancer also surrounded microvessels in adenomas with focal cancers. These findings suggest an involvement of EPHA2 in colon carcinogenesis, mainly in stages I and II, and probably through their effect on microvessel induction.

A kohitsugire is a paper fragment from an old manuscript written mainly in the Heian and Kamakura periods. Although they contain significant information for historical, literary, and paleographical study, because of their antique handwriting and description of historical incidents, there are many copies and counterfeits written several centuries later. In this study, radiocarbon ages of kohitsugire were measured by accelerator mass spectrometry (AMS). On the kohitsugire attributed to the famous calligraphists in the Kamakura period (Fujiwara no Sadaie and Prince Munetaka), 14C dating indicated that they were not genuine and should be excluded from the materials for study of the calligraphists. Calibrated 14C ages of the kohitsugire attributed to Fujiwara no Yukinari indicated the middle Heian period. This calligraphy was written on Tobikumogami paper, which has a billowing cloud pattern decorated with indigo-blue-dyed fiber. Although it was commonly accepted that the Tobikumogami is peculiar to the middle 11th to early 12th century, the results from 14C dating also suggested that the origin of the Tobikumogami would date back to the last of the 10th or the early 11th century, when Fujiwara no Yukinari flourished as a calligraphist. Calibrated 14C ages of the kohitsugire attributed to Nijo Tameuji and Reizei Tamesuke showed that they are fragments of old manuscripts describing lost tales and were written in the 13th14th century. Consequently, 14C dating clarified the existence of ancient tales which had been unknown and indicated their worth as a material for the study of classical Japanese literature.

depths corresponding to 3000, 5500, 7500 years BP with a period of approximately 2500 years, and 3) a further decrease toward the bottom. In order to understand the reasons for the changes, peat components were separated and their isotopic composition measured along with modern peat-forming vegetation. The selective decay of holocellulose is responsible for the rapid decrease of δ 13 C in the surface layers, and the transition from earlier vegetation caused the further decrease of δ 13 C near the bottom. The decay constant for holocellulose was estimated to be as small as 0.001 yr ‐1 . The variation of δ 13 C seemed to be synchronized with sea level change, but showed poor correlation with solar activity and the temperature change estimated from pollen analysis. The δ 13 C of peat mosses lacking in stomata would increase with the rise in atmospheric CO 2 . The increase in the atmospheric CO 2 occurring synchronously with sea level rise could be the reason for the periodical change. Some climatic information of the Holocene period may have been recorded in the Ozegahara bog peat.

潰瘍性大腸炎は,種々の全身合併症を伴うが,大腸以外の消化管に病変が併存することは稀である.われわれは,食道潰瘍を合併した潰瘍性大腸炎の1例を経験した.症例は19歳,男性.倦怠感を主訴に近医を受診した.貧血を認めたため上部消化管内視鏡を施行したところ上切歯列より25cmの食道に孤立性の浅い潰瘍を認めた.その後,腹痛,下痢が出現し徐々に増悪したため,下部消化管内視鏡検査を施行したところ全大腸に易出血性で連続性のびらんを認め,潰瘍性大腸炎と診断した. H2受容体拮抗剤およびサラゾスルファピリジンの投与にて食道病変は改善したが,大腸病変はステロイドの大量静注療法などの施行にもかかわらず増悪し,大腸全摘術を施行した.両者の関連性は明らかではないが,潰瘍性大腸炎では大腸以外の消化管のチェックも重要である.

New radiocarbon dates obtained from Late Pleistocene and Holocene deposits of the southern, eastern, and northern shores of Lake Baikal in 1995-2001 are presented, and the most important results of paleoenvironmental studies based on (super 14) C data are discussed. The following paleogeographic events were verified with the help of (super 14) C dating: 1) first Late Pleistocene glaciation (Early Zyryan); 2) Middle Zyryan interstadial; 3) loess formation during the Late Zyryan (Sartan) deglaciation; 4) warm and cold events in the Late Glacial; and 5) vegetation changes and forest successions during the Late Glacial and Holocene.

岐阜県高富低地において,ボーリング資料を用いて推定した地下構造と,1本のオールコア・ボーリング中の広域テフラおよび化石ケイソウ群集の分析から,堆積環境の変遷にっいて考察した.高富低地を構成する高富層(新称)は,下位から高富基底礫層,高富下部泥層,高富軽石質砂層および高富上部泥層に分けられる.上部泥層および下部泥層は湖成堆積物であり,上部泥層からはK-Ah,AT,Aso-4の広域テフラが検出された.高富軽石質砂層からは御岳火山起源の御岳第一浮石層(On-Pm1)および御岳藪原テフラ(On-Yb)などが検出され,高富軽石質砂層は木曽川流域に広く分布する木曽谷層に対比される.テフラの年代から古木曽川は,約100ka頃に美濃加茂付近より関市をまわる流路を通り,当時湖の環境であった本地域に高富軽石質砂層を一時的に流入させたと考えられる.オールコア・ボーリング資料が得られた西深瀬では,約31kaから現在まで泥炭湿地の環境が続いた.また,梅原断層以南の鳥羽川低地には,長良川が最近まで流下していた可能性が高い.

台湾東海岸で得た過去約1万年間の完新世サンゴ化石の9試料について,αスペクトル230Th/234U年代測定法とAMS14C年代測定法によりその形成年代を測り,海洋試料の14C年代の暦年較正に必要なローカルな海洋リザーバ効果を求めた.これまで報告がなかった台湾におけるΔR値は,完新世の9試料すべてがマイナスを示し,時代によって変化していた.これは,この地域が基本的に湧昇流などの影響を受けにくく,台風などの降雨による陸水の流入が激しいことから,大気と表層海洋が混じりやすいことによると考えられる.また,ΔRの完新世における時系列変化から,2～3cal kaと8.5cal kaには現在より温暖で降水が多く,4cal kaには寒冷少雨であったことが推定される.本研究で求められた台湾地域のローカルリザーバ補正により,数百年から千年間隔で繰り返し起こる台湾東海岸の地震性地殻変動の解析や,古地震の復元,さらに将来の大規模地震の長期的予測などを考える上で,年代に関してより精度の高い議論ができると期待される.

症例は66歳,男性. 2002年9月より心房細動を指摘され以後,内服薬で加療されていた. 2002年11月16日より,上腹部痛を自覚し当院を受診した.腹痛は,一過性で軽快したが, 12月18日,再び激しい間歇性の腹痛を認め入院となった.精査にて遠位空腸に著しい管状狭窄像を認めた.腫瘍性病変の存在は否定的であり,狭窄型虚血性小腸炎の術前診断にて,原因の確定診断と治療を兼ね, 2003年1月22日,腹腔鏡補助下手術を施行した.病変部小腸は漿膜面の発赤,壁の硬化を認め,小切開を加え小腸部分切除を施行した.その他に異常所見はなかった.術後経過は良好で,術後7病日に退院した.虚血性小腸炎の本邦報告例において腹腔鏡補助下の手術経験は数件のみであるが,腹腔鏡補助下手術は,低侵襲であるだけでなく良好な広い視野が得られ他疾患の鑑別にも有用と考えられた.

We have developed a prototype carbon extraction system for accelerator mass spectrometry (AMS) radiocarbon dating of archaeological iron remains by combusting them with a RF induction furnace. We have also successfully tested and used a method of carbon extraction from iron using a CuCl2 solution. Modifications to our carbon extraction systems and methods provide us acceptable performances; carbon yield is normally around 80% and the 14C background level is as low as 4248 ka BP in 14C apparent age. We have also conducted an iron refining experiment to examine the sources for carbon 14C age derived from iron, using established AMS 14C dating and carbon extraction systems. Our refining experiment was conducted on iron slag, which are by-products formed during iron smelting methods in the 7th century AD, and using modern charcoal as fuel. The aim of the experiment was to determine whether original carbon characteristics in the original iron materials would be preserved, or if the carbon signature would be replaced to some degree by the modern charcoal. AMS 14C measurements on the refined iron yielded 14C ages equivalent to those of the modern charcoal fuel. The result indicates that the original carbon signatures in the iron slag from 7th century production was replaced completely by modern carbon used in our experiment. The experiment confirms the assumption that 14C ages on iron products are associated with the fuel source of the iron smelting or refining process. We also report on the dating of iron slag materials excavated from the Gennaitouge iron smelting site, where 14C dates were consistent with the age of the site estimated by archaeological evidence.

症例は35歳,女性.妊娠24週目でイレウスを発症した. MRI検査で2年前の開腹手術の癒着によるイレウスと診断し手術を施行した.開腹すると,回腸末端が子宮底部に癒着して腸管の強い屈曲を認め,イレウスの原因となっていた.腸管の狭窄が高度であったため約60cmの腸管切除術を施行した.術後経過は良好で妊娠38週目に帝王切開で健康な男児を出産した.

A procedure to evaluate the structural integrity of a reactor vessel under CDA condition has been developed based on simulative experiments under CDA loading using 1/20- and 1/10-scale steel models of the demonstration FBR in Japan (DFBR). For the experiments, a constant pressure source has been developed using a gas accumulator. Simulation analyses were also conducted using the dynamic analysis program AUTODYN-2D, which can simulate fluid-structure interaction and non-linear material behaviour in two-dimensional geometry. The actual dynamic material properties, whose strain rates were from 0.1 to 10 s −1 , were used in the analyses. The pressure history and the dynamic response of structures were compared between experimental results and the analysis, and the appropriateness of the numerical analytical method for the CDA problem was confirmed. In both experimental and numerical approaches, the effect of internal structures has been investigated, and a drastic strain reduction was observed owing to the energy absorption by internal structures. Furthermore, material tests and element tests including weld joint tests and burst tests were carried out to define a rationalised strain limit under multi-axial dynamic loading condition. Using the developed evaluation procedure, a preliminary evaluation for DFBR was carried out and the robustness of the reactor boundary in DFBR against CDA loading was also confirmed.

This paper presents the variation of radiocarbon content in annual tree rings for the period AD 1413–1553, which includes the Spoerer Minimum period (AD 1415–1534). Since the variation of the production rate of 14C is strongly related to solar activity, the variation of 14C content in annual tree rings gives us information on the characteristics of variation of solar activity. We have studied solar activity during the grand solar minima, focusing especially on the stability of the 11-yr cycle. The minima are determined to have been almost free of sunspots. Our results, however, have revealed quite remarkably the existence of the 11-yr cycle for most of the time during the Spoerer Minimum. The 11-yr variation weakened around AD 1460–1510, suggesting that solar activity might have been strongly suppressed during these 50 yr.

Cytomegalovirus (CMV) infection has been reported to be a cause of refractory ulcerative colitis (UC). We herein report a case of refractory ulcerative colitis complicated by CMV infection requiring surgery. A 22-year-old man was admitted to our hospital with lower abdominal pain and bloody diarrhea. Under a diagnosis of acute UC, he was treated with prednisone 60 mg/day and sulfasalazine. Since his symptoms appeared to improve, the prednisone dosage was gradually reduced to 20 mg/day. After 5 months, he had an unexpected flare-up with fever and fresh anal bleeding. Colonoscopy demonstrated a punched out ulcer in the sigmoid colon. Biopsies by colonoscopy revealed cytomegalic inclusion bodies. Serologic and immunologic studies also suggested a recent CMV infection. Under a diagnosis of intractable UC complicated by a CMV infection, ganciclovir therapy was carried out, and the steroid therapy was tapered. Although the serum antigenemia became negative after the antiviral therapy, follow-up colonoscopy confirmed the severe stenosis after the punched-out ulcer healed completely. Since his symptoms did not improve, it was necessary to perform an elective proctocolectomy despite antiviral therapy. He was discharged with an uneventful postoperative course. It is important to recognize CMV colitis as a complication of inflammatory bowel disease, particularly in severe steroid-resistant colitis. Furthermore, in cases which fail to respond to antiviral treatment, the patient may ultimately require surgery.