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Cellulose synthesis in plants is believed to be carried out by the plasma membrane-associated rosette structure which can be observed by electron microscopy. Despite decade-long speculation, it had not been demonstrated whether the rosette is the site of catalytic activity of cellulose synthesis. To determine the relationship between this structure and cellulose synthesis, we successfully isolated detergent-insoluble rosettes from the plasma membrane of bean epicotyls. However, the purified rosettes did not possess cellulose synthesis activity in vitro. Conversely, detergent-soluble granular particles of ∼9.5–10 nm diameter were also isolated and exhibited UDP-glucose binding activity and possessed β-1,4-glucan (cellulose) synthesis activity in vitro. The particle, referred to as the catalytic unit of cellulose synthesis, was enriched with a 78 kDa polypeptide which was verified as sucrose synthase like by mass spectrometry and immunoblotting. The catalytic units were able to bind to the rosettes and retained the cellulose synthesis activity in the presence of UDP-glucose or sucrose plus UDP when supplemented with magnesium. The incorporation of the catalytic unit into the rosette structure was confirmed by immunogold labeling with anti-sucrose synthase antibodies under an electron microscope. Our results suggest that the plasma membrane-associated rosette anchors the catalytic unit of cellulose synthesis to form the functional cellulose synthesis machinery. [ABSTRACT FROM PUBLISHER]

Decomposition of the aromatics benzene (C6H6), toluene (C6H5CH3), and o-xylene (C6H4(CH3)2) was carried out in a plasma reactor packed with BaTiO3 pellets in the presence of various background gases. The order of decomposition efficiency was C6H6, irrespective of the background gas. Decomposition was suppressed when water vapor (H2O) was added to the reactant gas; the extent of the suppression was in the order C6H6>C6H5CH3>C6H4(CH3)2. When the reactant gas consisted of a mixture of C6H6, C6H5CH3, and C6H4(CH3)2, decomposition of C6H6 was suppressed, whereas the decompositions of C6H5CH3 and C6H4(CH3)2 were enhanced compared with the single-component decompositions of these aromatics. It seems that the migration of reactant molecules to the solid surface and the molecular sizes play important roles in these behaviors. [Copyright &y& Elsevier]

Presents a study which carried out the decomposition of benzene using a zeolite-hybrid reactor, a plasma reactor packed with a mixture of barium titanate pellets and zeolite pellets. Method; Results and discussion; Conclusion.

Background: While several complications related to pressure-wire (PW) have been reported, mechanistic justification has not always been offered. Furthermore, interference between a PW and a protruding side-branch stent has not been previously reported. The purpose of this study was to evaluate interference between PW-pullback from a main-branch with a protruded ostial stent deployed in a side-branch.Methods: In a polyurethane bifurcation vessel model, PW-pullback was performed in a main-branch following protruded ostial stenting in a side-branch. Tested PWs included PressureWire X, Comet, OptoWire, and Verrata. For each PW, pullback was performed through the same proximal cell of the protruded stent 20 times. Interference during PW-pullback was objectively analyzed with a fiberscope placed at the distal main-branch and classified into 3 grades according to the interaction with stent strut.Results: There were significant differences in the rate of interference between the PWs. No-interference, interference without strut traction, and interference with strut traction (i.e. stent deformation) were observed as follows: 17/20, 3/20, and 0/20 in PressureWire X; 19/20, 1/20, and 0/20 in Comet; 8/20, 10/20, and 2/20 in OptoWire; and 13/20, 2/20, and 5/20 in Verrata, respectively (p for any differences: <0.001). Visually identifiable major stent deformation was observed once in OptoWire due to the deep concave sensor window and twice in Verrata due to the proximal gap between the sensor and coiled-wire.Conclusions: PW-pullback in the main-branch after side-branch ostial stenting should be carefully performed to avoid stent deformation. Consideration on the specific mechanical features of the PW is also essential. [ABSTRACT FROM AUTHOR]

Stent placement for treating superficial femoral artery (SFA) lesions has been approved. The Zilver PTX stent, a drug-eluting stent (DES) for treating SFA lesions, has been available in Japan since 2012. However, the penetration rate of this DES has not yet been reported. This prospective multicenter registry study enrolled 314 patients (354 limbs) to be treated by stent placement in 2014 (UMIN000011551). The primary endpoint was the measurement of the penetration rate of the DES. The secondary endpoints were measuring the freedom from restenosis, freedom from target lesion revascularization (TLR), freedom from major adverse limb event (MALE), and the survival rate at 12 months postoperatively. Female patients comprised 28% participants. The mean age was 73.1 ± 9.2 years. A total of 56% patients had diabetes mellitus (DM), 36% patients were receiving hemodialysis, and 30% used cilostazol at baseline. The mean lesion length was 156 ± 101 mm, and the percentage of TASC II C/D lesions was 58%. Critical limb ischemia (CLI) was observed in 32% limbs. The penetration rates of the Zilver PTX stent were only 8%. The primary patency rate was similar between DES and bare-metal stents (BMS) at 12 months postoperatively (77 vs. 84%, p = 0.52). In this study, the rates of freedom from restenosis, freedom from TLR, freedom from MALE, and the survival rate at 12 months postoperatively were 83, 86, 85, and 89%, respectively. The penetration rate of a first-generation DES placement for treating SFA lesions is low in Japan. On the other hand, BMS is well utilized and its primary patency is acceptable. [ABSTRACT FROM AUTHOR]

In acentriolar higher plant cells, the surface of the nucleus acts as a microtubule-organizing center, substituting for the centrosome. However, the protein factors responsible for this microtubule organization are unknown. The nuclear surfaces of cultured tobacco BY-2 cells possess particles that generate microtubules. We attempted to isolate the proteins in these particles to determine their role in microtubule organization. When incubated with plant or mammalian tubulin, some, but not all, of the isolated nuclei generated abundant microtubules radially from their surfaces. The substance to induce the formation of radial microtubules was confirmed by SDS-PAGE to be a protein with apparent molecular mass of 38 kDa. Partial analysis of the amino acid sequences of the peptide fragments suggested it was a histone H1-related protein. Cloning and cDNA sequence analysis confirmed this and revealed that when the recombinant protein was incubated with tubulin, it could organize microtubules as well as the 38-kDa protein. Histone H1 and tubulin formed complexes immediately, even on ice, and then clusters of these structures were formed. These clusters generated radial microtubules. This microtubule-organizing property was confined to histone H1; all other core histones failed to act as organizers. On immunoblot analysis, rabbit antibodies raised against the 38-kDa protein cross-reacted with histone H1 proteins from tobacco BY-2 cells. These antibodies virtually abolished the ability of the nucleus to organize radial microtubules. Indirect immunofluorescence showed that the antigen was distributed at the nuclear plasm and particularly at nuclear periphery independently from DNA. [ABSTRACT FROM AUTHOR]

The decomposition of fluorocarbons (1%) in Ar was investigated using a surface discharge-type plasma reactor. To enhance the effectiveness of plasma chemical processing, we investigated the effects of catalysts and additives. The removal rate increased when the plasma reactor was packed with TiO2 pellets as a catalyst. The catalytic effect seems to be derived from the direct activation of the TiO2 surface by the plasma discharge, because significant UV emission and temperature increase were not observed in the plasma reactor. The removal rate was also enhanced when water vapor, oxygen, or hydrogen was added to the reactant. In addition, the presence of TiO2 or the additional gases or both depressed byproduct formation. Analysis of the reaction products suggested that the catalysts and additives enhanced the process by preventing the recombination of decomposed fragments. [Copyright &y& Elsevier]

Although seed plants have γ,-tubulin, a ubiquitous component of centrosomes associated with microtubule nucleation in algal and animal cells, they do not have discrete microtubule organizing centers (MTOCs) comparable to animal centrosomes, and the organization of microtubule arrays in plants has remained enigmatic. Spindle development in basal land plants has revealed a surprising variety of MTOCs that may represent milestones in the evolution of the typical diffuse a centrosomal plant spindle. We have isolated and characterized the γtubulin gene from a liverwort, one of the extant basal land plants. Sequence similarity to the γ-tubulin gene of higher plants suggests that the γ-tubulin gene is highly conserved land plants. The G9 antibody to fission yeast γ-tubulin recognized a single band of 55 kD in immunoblots from bryophytes. Immunohistochemistry with the G9 antibody clearly documented the association of γ-tubulin with various MTOC sites in basal land plants (e.g., discrete centrosomes with and without centrioles and the plastid surface in monoplastidic meiosis of bryophytes). Changes in the distribution of γ-tubulin occur in a cell cycle-specific manner during monoplastidic meiosis in the liverwort Dumortiera hirsuta. γ-tubulin changes its localization from the plastid surface in prophase I to the spindle,from the spindle to phragmoplasts and the nuclear envelope in telophase I, and back to the plastid surfaces in prophase II. In vitro experiments show that γ-tubulin is detectable on the surface of isolated plastids and nuclei of D. hirsuta, and microtubules can be repolymerized from the isolated plastids. γ-tubulin localization patterns on plastid and nuclear surfaces are not affected by the destruction of microtubules by oryzalin. We conclude that γ- tubulin is a highly conserved protein associated with microtubule nucleation in basal land plants and that it has. [ABSTRACT FROM AUTHOR]

Examines the effects of integrated xyloglucans on the suppression and acceleration of cell elongation in pea stem segments. Composition of plant cell walls; Determination of bound and solubilized xyloglucan; Properties of stem segments.

The rapid and facile generation of 4'-carbon radicals from oxime imidates of nucleosides via 1,5-hydrogen atom transfer induced by iminyl radicals was developed. The cyclization of 4'-carbon radicals with olefins, followed by the hydrolysis of imidate residues, provided various 2'- O ,4'- C - and 3'- O ,4'- C -bridged nucleosides. This operationally simple approach can be applied to the few-step syntheses of 6' S -methyl-2'- O ,4'- C -ethylene-bridged 5-methyluridine (6' S -Me-ENA-T) and S -constrained ethyl-bridged 5-methyluridine ( S -cEt-T).

Study Design: A retrospective multicenter observational study., Objective: To investigate correction surgeries that were performed in relatively aged patients in terms of mechanical complications (MCs) and their predictive factors., Summary of Background Data: The risk factors associated with MCs have not yet been well examined, especially in aged populations., Methods: We retrospectively reviewed 230 surgically treated ASD patients with an average age of 72.2 years. Twenty-eight patients with ASD caused by vertebral fractures were excluded. The minimum follow-up was 2 years. Postoperative MCs were defined as proximal junction kyphosis, distal junction kyphosis, pseudoarthrosis, rod breakage, and vertebral fractures. We divided all the ASD patients into two groups: patients with MC (the MC (+) group) and patients without MC (the MC (-) group). Radiographic parameters were evaluated before and immediately after surgery. The SRS-Schwab ASD classification and global alignment and proportion (GAP) score were also evaluated., Results: Of the 202 patients, 91 (45.0%) had MCs. The age at surgery was significantly higher in the MC (+) group than in the MC (-) group. Regarding radiographic parameters, postoperative global tilt (GT), pre- and postoperative thoracolumbar kyphosis (TLK), and postoperative thoracic kyphosis were significantly higher in the MC (+) group than in the MC (-) group. Other parameters, such as the proposed ideal alignment target of PI-LL<10, did not significantly affect MC rates. The GAP score was high in both groups and not significantly related to a higher rate of MC. Forward stepwise logistic regression indicated that the age at surgery, postoperative GT, and preoperative TLK were significant risk factors for MCs., Conclusion: Older age, higher postoperative GT, and higher pre and postoperative TLK can be risk factors for MCs. The GAP score was high in both groups and not significantly related to a higher rate of MC., Level of Evidence: 4.

Previous reports showed that GuideLiner (GL) and Guidezilla (GZ) can accommodate bulky and multiple devices beyond the official profiles. However, feasibility of kissing balloon technique (KBT) through these devices is unknown. The tested devices included 7Fr-GL/GZ and respective three types of 2.5 mm semi-compliant (SC) and non-compliant (NC) balloons: conventional model (CM), tapered-tip model (TM) and latest model (LM). First, three experienced operators attempted to advance all 21 combinations of the 2 balloons through GL/GZ on the guidewires and assessed the crossability in 3 grades: easy, difficult and impossible. Second, the only balloon combinations graded as easy by all operators were tested in the polyurethane-made bifurcation model which required KBT following cross-over stenting. Within the total of 42 device combinations, only one balloon combination of double LM-NC balloons was classified as easy in both GL/GZ by consensus opinion of the operators. While two combinations of LM-SC and LM-SC/NC balloons were classified as difficult in both GL/GZ, all four combinations of LM-SC/NC and CM/TM-NC balloons were classified as difficult only in GL. Other 32 combinations were all classified as impossible. In the bifurcation model, the combination of double LM-NC balloons using GL achieved KBT while the same balloon combination with GZ failed. The feasibility of KBT using child-catheter is highly dependent on the device characteristics. The combination of latest small-profile NC balloons through GL could be clinically applicable.