Abstract

We report a case of penetrating atherosclerotic causing cardiac tamponade and subadventitial hematoma. A 72-year-old man was transferred with sudden onset of chest pain and a subsequent collapse. A computed tomography scan showed a pericardial effusion and a low density shadow around the ascending aorta. An emergency operation was conducted with a diagnosis of intramural hematoma complicating cardiac tamponade.The patient underwent replacement of the ascending aorta. The specimen of the ascending aorta showed severe atherosclerosis and no intramural hematoma. Histological evaluation revealed a hemorrhage which connected a small intimal ulcer to the subadventitial hematoma. We think this case suggest the entry oriented etiology of intramural hematoma not rupture of a vasa vasorum.

Abstract

Physical, chemical, and biological properties of wood depend largely on the properties of cellulose, noncellulosic polysaccharides, and lignin, and their assembly mode in the cell wall. Information on the assembly mode in the main part of the ginkgo tracheid wall (middle layer of secondary wall, S2) was drawn from the combined results obtained by physical and chemical analyses of the mechanically isolated S2 and by observation under scanning electron microscopy. A schematic model was tentatively proposed as a basic assembly mode of cell wall polymers in the softwood tracheid as follows: a bundle of cellulose microfibrils (CMFs) consisting of about 430 cellulose chains is surrounded by bead-like tubular hemicellulose-lignin modules (HLM), which keep the CMF bundles equidistant from each other. The length of one tubular module along the CMF bundle is about 16 ± 2 nm, and the thickness at its side is about 3–4 nm. In S2, hemicelluloses are distributed in a longitudinal direction along the CMF bundle and in tangential and radial directions perpendicular to the CMF bundle so that they are aligned in the lamellae of tangential and radial directions with regard to the cell wall. One HLM contains about 7000 C₆-C₃ units of lignin, and 4000 hexose and 2000 pentose units of hemicellulose.

Abstract

We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium× A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species.

Abstract

The mechanism responsible for unusual hygro-mechanical properties of tension wood containing the gelatinous layer (G-layer) was investigated. Tension and normal wood specimens were sampled from the leaning stems of a 75- and a 40-year-old Kunugi oak (Quercusacutissima) tree, and the moisture dependencies of the longitudinal Young’s modulus and longitudinal dimensions were measured. The results, which were analyzed in relation to the anatomical properties of the specimens, revealed that the ratio of increase in the longitudinal Young’s modulus with drying was higher in the G-layer than in the lignified layer (L-layer); the longitudinal drying shrinkage displayed a similar pattern. It was found that the lattice distance of the [200] plane in the cellulose crystallite increased with drying, moreover, the half-width of the [200] diffraction peak increased with drying, which was remarkable in the tension wood. Those results suggest that in the green state, the polysaccharide matrix in the G-layer behaves like a water-swollen gel; however, it is transformed into a condensed and hard-packed structure by strong surface tension during moisture desorption, which is a form of xero-gelation. However, in the L-layer, condensation and subsequent xero-gelation of the polysaccharide matrix was prevented by the hydrophobic lignin that mechanically reinforces the matrix.

Abstract

Fluoroalkyl end-capped acrylic acid oligomer [R_F-(ACA)_n-R_F]/, 2-(methacryloyloxy)ethanesulfonic acid oligomer [R_F-(MES)_n-R_F]/, 2-acrylamido-2-methylpropanesulfonic acid oligomer [R_F-(AMPS)_n-R_F]/polyaniline [PAn] nanocomposites were prepared by the polymerization of aniline initiated by ammonium persulfate in the presence of the corresponding oligomers, respectively. These fluorinated oligomers were also applied to the preparation of the corresponding fluorinated oligomers/phenyl-capped aniline dimer (An-dimer: N,N′-diphenyl-1,4-phenylenediamine) nanocomposites by the interaction of the fluorinated oligomers with An-dimer. These fluorinated composites thus obtained were found to afford nanometer size-controlled fine particles possessing a good dispersibility and stability in water and traditional organic media such as methanol. UV–vis spectra of R_F-(MES)_n-R_F/PAn nanocomposites and R_F-(AMPS)_n-R_F/PAn nanocomposites showed the similar absorption peaks around 350, 430, and 780 nm to those of the usual Brønsted acid-doped PAn; however, interestingly, R_F-(ACA)_n-R_F/PAn nanocomposites were found to exhibit only an absorption peak around 430 nm based on the polaron transition.

Figure

Abstract

We investigated the effect of light intensity on diurnal differences in secondary wall formation of tracheids. Saplings of Cryptomeria japonica were grown in growth chambers with light intensity cycles set for 12-h high light: 12-h low light by combining two of four light intensity levels: 1.5, 2.8, 4.3, and 10.0 klx. Volumetric changes of differentiating cells were monitored by measuring the tangential strain on the inner bark surface, and the innermost surface of developing secondary walls of differentiating tracheids during the high-light and low-light periods was observed by field-emission scanning electron microscopy. Changes in the aspects of the innermost surface of developing secondary walls and the tangential strain corresponded to changes in the light intensity level. Cellulose microfibrils were clearly observed when the light intensity was high (10.0 or 4.3 klx) and the volume of differentiating cells was low, while abundant amorphous material was observed when the light intensity was lowest (1.5 klx) and the cells were turgid, regardless of the light intensity cycle. These results suggest that the diurnal periodicity in the supply of cell wall components to developing secondary walls is associated with changes in light intensity during the photoperiodic cycle.

Abstract

Treatment of large (diameter 12–25 mm) or giant (diameter >25 mm) cerebral aneurysms with a broad neck in the cranio-cervical area is difficult and carries relatively high risks, even with surgical and/or endovascular methods. To this end, we have been developing a high-performance, self-expanding stent graft which consists of a commercially available NiTi stent (diameter 5 mm, length 20 mm) initially covered with a thin microporous segmented polyurethane membrane fabricated by the dip-coating method. Micropores are then created by the excimer laser ablation technique, and the outer surface is coated with argatroban. There are 2 types of micropore patterns: circular-shaped pore type (pore: diameter 100 μm, opening ratio 12.6%) and the bale-shaped pore type (pore: size 100 × 268 μm, opening ratio 23.6%). This self-expanding stent graft was tested on side-wall aneurysms of both canine carotid arteries that were experimentally induced using the venous pouches from the external jugular veins, with the self-expanding stent graft on one side and a bare self-expanding stent on the other side. All carotid arteries were patent and free of marked stenosis after 1 month. All aneurysms were occluded by stent grafts, while patent in those treated with bare stents. Histologically, the stent grafts with bale-shaped micropores and a high opening ratio were associated with less intimal hyperplasia (187 ± 98 μm) than the bare stents (341 ± 146 μm) or the stent grafts with circular micropores and a low opening ratio (441 ± 129 μm). A pore ratio of 23.6% was found to control intimal growth.

Abstract

We measured the lattice spacing of the cellulose in sugi (Cryptomeria japonica D. Don) and hinoki (Chamaecyparis obtusa Endl.) cell walls under wet and dry conditions. We gave all specimens repeated wet-and-dry treatments and tried to induce substantial changes in the microstructure of the wood cell wall. Macroscopic dimensions, measured using a micrometer, showed well-known behaviors, that is, shrinkage by drying and swelling by wetting, which were unaffected after the repeated wet-and-dry treatments in both longitudinal and tangential directions. On the other hand, lattice spacing, measured using an X-ray diffractometer, showed different results. In particular, d₂₀₀ lattice spacing expanded considerably with drying in the early stages of repeated wet-and-dry treatments. The d₂₀₀ lattice spacing in the dried specimen then became gradually smaller in the later stages, whereas no such dynamic change was observed in d₀₀₄ lattice spacing throughout the repeated wet-and-dry treatments. Once the d₂₀₀ lattice spacing in the dried specimen had become smaller after giving wet-and-dry treatments, it did not recover, even after soaking in distilled water for 1 month. These results suggest that repeated drying and re-swelling caused structural changes in the wood cell wall, specifically an interfacial separation between cellulose microfibrils and matrix substances.

Abstract

Head-to-head-type styrene and substituted styrene dimers bearing two fluoroalkyl end-groups have been efficiently synthesized by a simple reaction of perfluoroalkyl iodide with styrene under radical conditions as a mixture of meso and racemic forms. The meso form obtained from the mixture by recrystallization gave a crystal suitable for X-ray diffraction study and the crystal structure was found to be based on π-stacking of benzene rings and aggregation of fluoroalkyl chains. Dynamic light scattering measurements showed that meso-styrene dimers bearing two fluoroalkyl end-groups can form the nanometer size-controlled self-assemblies through the intermolecular π-stacking of benzene rings and aggregation of end-capped fluoroalkyl groups in methanol.

Figure

Abstract

Abstract

We attempted to measure in situ the tensile elastic moduli of individual component polymers with a three-dimensional (3D) assembly mode in the cell walls of Sugi (Cryptomeria japonica D. Don) without isolating the polymers. To prepare wood tangential slices [50 × 6 × 0.2 mm (L × T × R)] consisting of lignin with a 3D assembly mode in the cell walls, cellulose and hemicellulose were removed using the method of Terashima and Yoshida (2006) to obtain methylated periodate lignin slices. To prepare wood slices consisting of polysaccharide with a 3D assembly mode in the cell walls, lignin was removed using the method of Maekawa and Koshijima (1983) to obtain holocellulose slices. Static tensile test was applied to determine the elastic moduli of 3D lignin and 3D polysaccharide slices. The followings were revealed. The elastic modulus of the 3D lignin slices was 2.8 GPa, regardless of the microfibril angle (MFA) in the slices. The elastic moduli of the 3D polysaccharide slices with MFAs of 14°, 23°, 34°, and 42° were 18, 12, 9, and 4 GPa, respectively. The former shows that the lignin with a 3D assembly mode behaves as an isotropic substance in the cell walls, while the latter suggests that the 3D polysaccharide slice shows marked anisotropic structure in the cell wall. Despite the fact that cellulose content increased after lignin removal, values of substantial elastic modulus of the cell wall slightly decreased regardless of MFA. Following two possible reasons were pointed out for explaining this phenomenon. First, lignin removal caused an artifactual deterioration in the polysaccharide slices at the level of macromolecular aggregate. Second, rigid and fusiform-shaped cellulose crystallites are dispersed in the soft matrix of amorphous polysaccharide, and those are loosely connected to each other by the intermediary of matrix polysaccharide. Those suggest that the rigid cellulose crystallite can optimize its strong mechanical performance in the polysaccharide framework of the wood cell wall in combination with the ligninification.

Abstract

The purpose of this study is to investigate the effect of repeated moisture change on the crystallinity and crystal size of cellulose microfibrils (CMF) in sugi (Cryptomeria japonica D.Don) and karamatsu (Larix kaempferi Gord.) wood cell wall. Based on obtained results, we discussed the qualitative change in the fine structure of CMF caused by repeated dry-and-wet (RDW) treatments. Green quarter-sawn specimens (5 × 16 × 15 mm in thickness × length × width) and microcrystalline cellulose powder (Avicel) were prepared, and these specimens were subjected to 7 times at most of heated or unheated RDW treatments. After giving RDW treatments, specimens were seasoned to the fiber saturated point and absolutely dried. Wide angle X-ray diffraction measurements were adopted to determine the crystallinity and the crystal size in each condition. Results indicate that crystallinity and crystal size in wood specimens gradually increased with the progress of heated or unheated RDW treatments, while no such increases were observed in Avicel powder. Those results suggest that RDW treatments promote the crystallization of CMF in wood cell wall, regardless of heating. We presume that noncrystalline cellulose forms hydrogen bonding with the cellulose at the surface of crystalline region with the progress of RDW treatments, thus enlarging the crystal size. Avicel powder did not show features that were observed in wood specimens by RDW treatments, because it contained few noncrystalline cellulose.

Abstract

Fluoro(silyl)acetylenes, which were prepared by reaction of 1,1-difluoroethylene with silyl chlorides, reacted with triethylamine to give dark-brown colored polyfluoro(silyl)acetylene powders in excellent to moderate isolated yields. In contrast, the corresponding nonfluorinated acetylene was unable to react with triethylamine at all to afford poly(silyl)acetylene under similar conditions. Polyfluoro(silyl)acetylenes thus obtained were nanometer size-controlled cubic fine particles with a good dispersibility and stability in a variety of solvents. These polyfluoro(silyl)acetylene nanoparticles exhibited clear absorption and emission spectra related to the conjugated units in polymer main chain. Furthermore, these polyfluoro(silyl)acetylene nanoparticles were applied to the surface modification of poly(methyl methacrylate) [PMMA] film to exhibit a higher oleophobicity imparted by fluorine on their surface, compared to that on the reverse side.

Figure

Abstract

We investigated the influences of chemical pretreatments and subsequent repeated dry-and-wet (RDW) treatments on the mechanical linkage between cellulose microfibrils (CMFs) and matrix substances (MT) in wood cell wall. Sugi (Cryptomeria japonica D. Don) quarter-sawn specimens were subjected to various types of chemical pretreatments, including ethanol and benzene extraction, delignification, alkali extraction, and hygrothermal treatment, to give substantial damages to principal constituents of wood cell wall, followed by 5 times of RDW treatment. After giving chemical pretreatment, the d-spacing of (200) lattice plane of cellulose I_β (d₂₀₀), the crystallinity of wood cell wall, and the crystal size of the cellulose were measured at the fiber saturated point, using X-ray diffraction techniques. Thereafter, these were measured again at the absolutely dried condition in the process of subsequent RDW treatments. The d₂₀₀ in specimens, which were given to light pretreatments, largely expanded by drying at the early stages of RDW treatments, then it decreased and became constant after 5 times of RDW treatments. On the other hand, d₂₀₀ in specimens, which were given to intensive pretreatments, remained constant at a relatively small level throughout the whole process of RDW treatments. After 5 times of RDW treatments, d₂₀₀ became similar values between the above two groups. This suggests that RDW treatments have similar effects as intensive pretreatments, which induce substantial damages to the microscopic region in the wood cell wall such as interfacial separation between CMF, MT, and so forth. These defects would weaken mechanical interaction between CMF and MT in the wood cell wall during drying.

Abstract

Although sarcoidosis may involve the myocardium, there is little available information on its treatment, especially in cases requiring surgery, such as left ventricular restoration or mitral valve repair. This report presents two surgical cases with cardiac sarcoidosis treated by left ventricular restoration and mitral valve repair for a ventricular aneurysm and dilated cardiomyopathy with mitral regurgitation.

Abstract

We described a 71-year-old female of aneurysm of the left sinus of Valsalva from mycotic origin. She underwent aortic valve replacement 11 years ago. Repeated CT scans showed rapidly growing aneurysm below the left coronary ostium. On sixth day after the admission, she suddenly developed myocardial ischemia complicated with ventricular fibrillation. The patient was treated with emergent aortic root replacement and she recovered. We recommend emergent surgical repair of mycotic saccular aneurysm of the left sinus of Valsalva because a delay of surgery could be fatal.

Abstract

A 58-year-old female presenting with congestive heart failure due to a fistula between an aortic false aneurysm and the superior vena cava (SVC) is described. She had a history of Takayasu’s arteritis (TA) and she had undergone aortic valve and ascending aorta replacement and coronary artery bypass grafting 6 years before. The false aneurysm had occurred 1 year after the surgery, and she had been conservatively managed. The operation revealed that the cause of the false aneurysm was the detachment of the two proximal saphenous vein anastomoses to the ascending aortic graft. After the surgery, the patient made an uneventful recovery. A false aneurysm of the ascending aorta is one of the most serious complications after replacement of the ascending aorta for patients with TA (Miyata et al. in J Vasc Surg 27:438–445, 1998). We herein present the exceptional case of a fistula between an aortic false aneurysm and the SVC that occurred after ascending aorta graft replacement.

Abstract

A wood block often changes its original dimension when it is kept in hot water. This is because the locked-in component of the growth stress is released by hygrothermal softening of the cell wall matrix. However, it is still unknown whether or not heating is a necessary requirement for the release of the visco-elastic locked-in component of the growth stress (GS). To solve this question, Agathis green specimen was treated by drying and re-swelling at room temperature, followed by boiling at 120 °C and 0.2 MPa. Then dimensions of green, re-swollen, and boiled specimens were measured at room temperature. Based on the obtained data, it was discussed whether the drying and subsequent re-swelling treatments release the visco-elastic locked-in component of the GS in green wood. The following conclusions were obtained. Locked-in component is released in part by the drying and subsequent re-swelling treatments without heating. After repeating the drying and subsequent re-swelling treatments, viscoelastic components are gradually released; however, rapid or complete release is made by boiling in hot water.

Abstract

Tension wood, when kiln-dried, is likely to deform hugely, which is probably caused by a gelatinous layer of the gelatinous fiber. To elucidate the mechanism behind the deformation of tension wood during kiln-drying, the strains experienced by tension wood during a hygrothermal treatment that is akin to an early stage of kiln-drying were investigated. Normal wood elongated along the longitudinal axis after the first treatment and leveled off with repetitive treatments. During the first treatment, tension wood contracted significantly along the longitudinal axis, followed by small subsequent contractions, which occurred during successive treatments. This characteristic hygrothermal behavior of tension wood correlated with the areal ratio of the gelatinous layer. One of the possible reasons why tension wood behaves differently was thought to be particular behavior of gelatinous layer. This finding will contribute to the development of appropriate seasoning method for tension wood by clarifying the mechanism behind the deformation of the gelatinous layer.