Publications by authors named "Hisashi Abe"

Background And Aims: Pit pairs and their filter-like partition, i.e. pit membranes, play important roles as water pathways, barriers and regulators in the water-conducting system of angiosperms.

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Wood is difficult for most animals to digest due to large amounts of indigestible polymers, but some wood-feeding insects are considered to be able to utilize it as food with the aid of microbial symbionts. Most members of flower longicorn beetles (Coleoptera: Cerambycidae: Lepturinae) feed on nectar and pollen of flowers as adults and wood as larvae. In some lepturines, associations with yeasts are known: female adults possess fungus-storing organs (termed mycetangia) at ovipositors, and larvae also possess such organs (termed mycetomes) in their midguts to carry the associated yeasts.

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Understanding the actual situation of radiocesium (Cs) contamination of trees caused by the Fukushima nuclear accident is essential for predicting the future contamination of wood. Particularly important is determining whether the Cs dynamics within forests and trees have reached apparent steady state. We conducted a monitoring survey of four major tree species (Japanese cedar, Japanese cypress, konara oak, and Japanese red pine) at multiple sites.

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Lignin-decomposing ability of several bacteria and the degradation mechanism have been revealed in vitro. However, the abundance of such bacteria in decayed wood in nature remains unknown at genus and species levels. This study was aimed at identifying bacterial communities in the decayed wood coexisting with white-rot fungi, which play a potential role in lignin degradation, and predicting the functional profile of bacterial lignin degradation in wood via bacterial community analyses.

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We developed an accurate and precise system for controlling dew points by using an active pressure control system in a primary standard humidity generator. By using this system, an adjustment capability to a target value of 0.0008 °C was attained for dew-point generation, compared with the previous value of approximately 0.

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To understand the changes in radiocesium (Cs) concentrations in stem woods after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, we investigated Cs concentrations in the bark, sapwood, heartwood, and whole wood of four major tree species at multiple sites with different levels of radiocesium deposition from the FDNPP accident since 2011 (since 2012 at some sites): Japanese cedar at four sites, hinoki cypress and Japanese konara oak at two sites, and Japanese red pine at one site. Our previous report on Cs concentrations in bark and whole wood samples collected from 2011 to 2015 suggested that temporal variations were different among sites even within the same species. In the present study, we provided data on bark and whole wood samples in 2016 and separately measured Cs concentrations in sapwood and heartwood samples from 2011 to 2016; we further discussed temporal trends in Cs concentrations in each part of tree stems, particularly those in Cs distributions between sapwood and heartwood, in relation to their species and site dependencies.

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We report a simple, robust cavity ring-down spectroscopy system to reliably measure trace moisture in gases at parts-per-trillion (ppt) levels. The performance of the system was evaluated on the basis of experiments performed in a manner traceable to the International System of Units. The obtained result was in good agreement with the primary trace-moisture standard at 12 nmol/mol (12 ppb) in N2 in amount-of-substance fraction.

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Phloem production and structural development were interlinked with seasonal variation in the primary and secondary metabolites of phloem. Novel microtechniques provided new perspectives on understanding phloem structure and chemistry. To gain new insights into phloem formation in Norway spruce (Picea abies), we monitored phloem cell production and seasonal variation in the primary and secondary metabolites of inner bark (non-structural carbohydrates and phenolic stilbene glucosides) during the 2012 growing season in southern and northern Finland.

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To investigate the biological mechanism by which trees control the changes in microfibril (MF) orientation among secondary cell wall layers of conifer tracheids, we studied seasonal variation in the orientation of newly deposited MFs during tracheid cell wall development in Japanese cedar (Cryptomeria japonica D. Don) trees growing in Central Japan (36°36'N, 140°39'E). Sample blocks were repeatedly collected from four 16-year-old clones of different origins during the growing season of 2010 to investigate the hypotheses that changes in cellulose MF orientation between wall layers exhibited seasonal and clonal differences.

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Objectives: Pancreatic cancer is one of the most lethal malignancies; its poor prognosis is strongly associated with invasion and metastasis. Expression of S100A4 has been reported to correlate with poor prognosis in various cancers. We have investigated the role of S100A4 in pancreatic cancer tumorigenesis and its clinicopathologic significance.

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Objective: The aim of this study was to compare the accuracy, sensitivity, and positive predictive value of C-arm CT with those of MDCT in the detection of hepatocellular carcinoma.

Materials And Methods: We retrospectively evaluated the cases of 50 patients with nodules of hepatocellular carcinoma who underwent biphasic MDCT and selective C-arm CT with flat-detector angiographic systems. We evaluated arterial phase C-arm CT images and the corresponding biphasic MDCT images of 59 hepatic areas in 50 patients.

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The extent of tropical forest has been declining, due to over-exploitation and illegal logging activities. Large quantities of unlawfully extracted timber and other wood products have been exported, mainly to developed countries. As part of the export monitoring effort, we have developed methods for extracting and analyzing DNA from wood products, such as veneers and sawn timbers made from dipterocarps, in order to identify the species from which they originated.

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An 86-year-old man with dysphagia underwent gastrointestinal fiberscopy (GIF) and was found to have a circumferential type 3 advanced carcinoma in the upper thoracic esophagus and a type 2 tumor in the posterior wall of the gastric body. Microscopic examination of biopsy specimens of both tumors demonstrated moderately differentiated squamous cell carcinoma. He was diagnosed as having stage IVb (T3N0M1b) esophageal carcinoma with gastric wall metastasis.

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During retrograde transvenous sclerotherapy for gastric varices, sufficient opacification of the target varices on venography is essential for successful treatment. However, venography sometimes cannot identify target varices due to overlapping adjacent collateral vessels or leakage of contrast medium to other outflow veins. We report how C-arm CT images acquired using a flat-panel detector angiography system helped to identify target varices and predict the distribution of a sclerosant, which resulted in safer sclerotherapy and increased operator confidence.

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We examined the species richness and host utilization patterns of wood-inhabiting aphyllophoraceous fungi (polypores and related fungi) in an old-growth beech and oak forest in a cool, temperate area of Japan. Coarse woody debris (CWD) > or = 20 cm diam within a 6 ha plot was surveyed in Sep 2002. Tree genus, diameter, decay class and tree part of CWD samples were recorded.

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The morphological variation and structure-function relationships of xylem parenchyma still remain open to discussion. We analyzed the three-dimensional structure of a poorly known type of xylem parenchyma with disjunctive walls in the tropical hardwood Okoubaka aubrevillei (Santalaceae). Disjunctive cells occurred among the apotracheal parenchyma cells and at connections between axial and ray parenchyma cells.

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Objective: This study compares the diagnostic accuracy of C-arm CT with digital subtraction angiography (DSA) in identifying tumor-feeding arteries during superselective transarterial chemoembolization (TACE).

Materials And Methods: Thirty-three consecutive patients with hepatocellular carcinoma (HCC) underwent superselective TACE using a flat-detector angiographic system. Angiographic operators determined which feeding arteries were potentially supplying the target tumor.

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Purpose: Contrary to the extensive data accumulated regarding pancreatic carcinogenesis, the clinical and molecular features characteristic of advanced stage (stage III and IV) disease are unknown. A comprehensive study of pancreatic cancers from patients who have succumbed to their disease has the potential to greatly expand our understanding of the most lethal stage of this disease and identify novel areas for intervention.

Materials And Methods: Rapid autopsies were performed on 76 patients with documented pancreatic cancer.

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Background And Aims: Although the lateral movement of water and gas in tree stems is an important issue for understanding tree physiology, as well as for the development of wood preservation technologies, little is known about the vascular pathways for radial flow. The aim of the current study was to understand the occurrence and the structure of anatomical features of sugi (Cryptomeria japonica) wood including the tracheid networks, and area fractions of intertracheary pits, tangential walls of ray cells and radial intercellular spaces that may be related to the radial permeability (conductivity) of the xylem.

Methods: Wood structure was investigated by light microscopy and scanning electron microscopy of traditional wood anatomical preparations and by a new method of exposed tangential faces of growth-ring boundaries.

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A unique fiber spinning was found in protoplasts from white birch (Betula platyphylla) leaves under an acidic medium containing high concentration of Ca(2+). After expanding from 10 to 100 microm in diameter under the culture condition, the protoplast started secreting a gigantic fiber while moving in a spiral way. Real time video analyses elucidated that the orientation, rate and pattern of the motion were directed due to the inverse force of the fiber spinning.

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Objectives: To report our therapeutic results in prostate cancer using double-mutated adenovirus AxdAdB-3, which has a mutation of E1A and deletion of E1B 55KD. Advanced prostate cancer can harbor multiple genetic alterations, including p53 and Rb/E2F/p16, and is often refractory to hormonal ablation. Virotherapy has been used to target these genetic abnormalities using mutant oncolytic adenovirus for the management of other cancers.

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Aim: Recently, many diagnostic modalities have been developed for the detection of hepatocellular carcinoma (HCC). Of these, a less invasive and more accurate diagnostic procedure is desirable. This study was undertaken to compare combined dynamic multidetector row helical computerized tomography (MDCT) and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) with combined CT hepatic arteriography (CTHA) and CT during arterial portography (CTAP) for the detection of hypervascular HCC.

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Due to deficiencies of clinical staging, magnetic resonance (MR) imaging is being increasingly used in the pre-treatment work-up of cervical cancer. Lymph node status, as evaluated by advanced imaging modalities, is also being incorporated into management algorithms. Familiarity with MR imaging features will lead to more accurate staging of cervical cancer.

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Purpose: The purpose of this study was to evaluate the efficacy of 3-dimensional computed tomographic angiography (3D CTA) using 16-channel multidetector-row helical computed tomography (MDCT) in the preoperative visualization of laparoscopic gastrectomy for early gastric cancer.

Materials And Methods: Twenty consecutive patients with early gastric cancer who underwent computed tomographic (CT) examination using 16-channel MDCT (0.625 mm x 16) before surgery were included in this study.

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