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The etiological agents of streptococcosis were isolated from diseased olive flounder collected on the Jeju island of Korea. A total of 151 bacterial isolates were collected between 2003 and 2006. The isolates were examined using various phenotypic and proteomic analyses, including sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting, and glycoprotein assays. In addition, isolates were grown on blood agar to assess hemolytic activity, and biochemical assays were performed using the API20 Strep kit. Our results revealed that all isolates were nonmotile, Gram-positive cocci that displayed negative catalase and oxidase activities. Multiplex PCR assays revealed that 43% and 57% of the isolates were Streptococcus iniae and Streptococcus parauberis, respectively. These results were consistent with those of the SDS-PAGE and immunoblot analyses using whole-cell lysates of bacterial isolates. Significant differences were observed with respect to the Voges-Proskauer, pyrrodonyl arylamidase, alkaline phosphatase, and hemolytic activities of the S. iniae and S. parauberis isolates. Isolates of S. iniae displayed uniform profiles in the immunoblot and glycoprotein assays; however, immunoblot assays of S. parauberis isolates (using a chicken IgY antibody raised against a homologous isolate) revealed three distinct antigenic profiles. Our findings suggest that S. parauberis and S. iniae are endemic pathogens responsible for the development of streptococcosis in olive flounder.

Background and Objectives: To evaluate the visual and anatomical outcomes of surgery for retinal detachment due to macular hole in highly myopic eyes with pronounced posterior staphyloma., Patients and Methods: Data for all patients with high myopia who underwent surgery for retinal detachment resulting from macular hole from 1993 to 2002 in one hospital were evaluated. Patient characteristics, best-corrected visual acuity preoperatively and at last examination, surgical technique, anatomical success, and follow-up period were extracted and analyzed statistically., Results: Twenty-six of the 27 patients (28 eyes) were female (96%) with a mean age of 59.8 years; mean follow-up was 17.3 months. Mean axial length was 29.1+/-2.74 mm; mean myopia was -16.4 +/- 3.1 diopters. Marked posterior staphyloma was detected in 71%. Seven eyes had undergone failed scleral buckling as the primary procedure; intravitreal SF6 injection was the primary procedure in 12 eyes. Twenty-three eyes underwent deep vitrectomy with use of high viscosity silicone oil. Overall anatomical success was achieved in 92.9% (26 of 28 eyes); 78.6% had visual improvement., Conclusions: Vitreous surgery combined with other necessary adjunct procedures such as membrane peeling and use of retinal tamponade, as a primary or a secondary procedure, seems to be successful in achieving retinal reattachment in eyes with macular hole and posterior staphyloma.

Objective: To assess the impact of a school-based nutrition education intervention aimed at increasing the consumption of fruits and vegetables., Design: The intervention programme increased the provision of fruits and vegetables in schools and provided a range of point-of-purchase marketing materials, newsletters for children and parents, and teacher information. Curriculum materials at age 6-7 and 10-11 years were also developed and utilised. Evaluation was undertaken with groups of younger (aged 6-7 years) and older (aged 10-11 years) children. Methods included 3-day dietary records with interview and cognitive and attitudinal measures at baseline, with follow-up at 9 months, in intervention and control schools., Setting: The work was undertaken in primary schools in Dundee, Scotland., Subjects: Subjects comprised 511 children in two intervention schools with a further 464 children from two schools acting as controls., Results: Children (n=64) in the intervention schools had an average increase in fruit intake (133+/-1.9 to 183+/-17.0 g day(-1)) that was significantly (P<0.05) greater than the increase (100+/-11.7 to 107+/-14.2 g day(-1)) estimated in children (n=65) in control schools. No other changes in food or nutrient intake were detected. Increases in scores for variables relating to knowledge about fruits and vegetables and subjective norms were also greater in the intervention than in the control group, although taste preferences for fruits and vegetables were unchanged., Conclusions: It is concluded that a whole school approach to increasing intakes of fruits and vegetables has a modest but significant effect on cognitive and attitudinal variables and on fruit intake.

The function of the arabinan and galactan side-chains of pectin remains unknown. We describe 13C NMR experiments designed to yield spectra from the most mobile polymer components of hydrated cell walls isolated from a range of plant species. In pectin-rich cell walls, these corresponded to the pectic side-chains. The arabinan side-chains were in general more mobile than the galactans, but the long galactan side-chains of potato pectin showed high mobility. Due to motional line-narrowing effects these arabinan and galactan chains gave 13C NMR spectra of higher resolution than has previously been observed from 'solid' biopolymers. These spectra were similar to those reported for the arabinan and galactan polymers in the solution state, implying time-averaged conformations resembling those found in solution. The mobility of the highly esterified galacturonan in citrus cell walls overlapped with the lower end of the mobility range characteristic of the pectic side-chains. The cellulose-rich cell walls of flax phloem fibres gave spectra of low intensity corresponding to mobile type II arabinogalactans. Cell walls from oat coleoptiles appeared to contain no polymers as mobile as the pectic arabinans and galactans in primary cell walls of the other species examined. These properties of the pectic side-chains suggest a role in interacting with water.

In the Arabidopsis mutant irx3, truncation of the AtCesA7 gene encoding a xylem-specific cellulose synthase results in reduced cellulose synthesis in the affected xylem cells and collapse of mature xylem vessels. Here we describe spectroscopic experiments to determine whether any cellulose, normal or abnormal, remained in the walls of these cells and whether there were consequent effects on other cell-wall polysaccharides. Xylem cell walls from irx3 and its wild-type were prepared by anatomically specific isolation and were examined by solid-state NMR spectroscopy and FTIR microscopy. The affected cell walls of irx3 contained low levels of crystalline cellulose, probably associated with primary cell walls. There was no evidence that crystalline cellulose was replaced by less ordered glucans. From the molecular mobility of xylans and lignin it was deduced that these non-cellulosic polymers were cross-linked together in both irx3 and the wild-type. The disorder previously observed in the spatial pattern of non-cellulosic polymer deposition in the secondary walls of irx3 xylem could not be explained by any alteration in the structure or cross-linking of these polymers and may be attributed directly to the absence of cellulose microfibrils which, in the wild-type, scaffold the organisation of the other polymers into a coherent secondary cell wall., (Copyright 2002 Elsevier Science Ltd.)

Native cellulose in higher plants forms crystalline fibrils a few nm across, with a substantial fraction of their glucan chains at the surface. The accepted crystal structures feature a flat-ribbon 21 helical chain conformation with every glucose residue locked to the next by hydrogen bonds from O-3' to O-5 and from O-2 to O-6'. Using solid-state NMR spectroscopy we show that the surface chains have a different C-6 conformation so that O-6 is not in the correct position for the hydrogen bond from O-2. We also present evidence consistent with a model in which alternate glucosyl residues are transiently or permanently twisted away from the flat-ribbon conformation of the chain, weakening the O-3' - 0-5 hydrogen bond. Previous molecular modelling and the modelling studies reported here indicate that this 'translational' chain conformation is energetically feasible and does not preclude binding of the surface chains to the interior chains, because the surface chains share the axial repeat distance of the 21 helix. Reduced intramolecular hydrogen bonding allows the surface chains to form more hydrogen bonds to external molecules in textiles, wood, paper and the living plant.

The kinetics of trichloroethene (TCE) reductive dechlorination mediated by humic-Ni complexes in homogeneous aqueous solution using titanium(III) citrate as the bulk reductant was examined under various environmental conditions (e.g., pH and ionic compositions). Using Ca2+, Zn2+, and Hg2+ ions to vary Aldrich humic acid (HA)-Ni complex concentrations, pseudo-first-order rate constants for TCE reduction were observed to be proportional to HA-Ni levels (as calculated by speciation modeling), confirming HA-Ni complexes as the probable active mediator species. TCE reduction by HA-Ni was observed to be strongly pH dependent and could be due to both the variations of HA-Ni concentration and Eh with pH. Evidence is presented which suggests that quinone moieties may not be crucial for the humic-Ni mediated reduction of TCE. A variety of natural soil and aqueous humic material and Ni systems were examined, and some showed reactivity toward TCE. Humic-metal complexes may be important electron-transfer mediators in natural systems.

The objective of this paper is to present a definition for dietary fibre based on recent advances that have taken place not only in human nutrition but also in plant cell-wall science and animal nutrition. We propose a physiologically based framework definition but, recognizing the diversity of dietary fibre, we have proposed further classifications within this framework. We also suggest that dietary fibre be removed from the carbohydrate group of nutrients because some compounds defined as dietary fibre are not chemically carbohydrates. The definition and classification system clearly highlight areas where further studies are needed.

It has been controversial for many years whether in the cellulose of higher plants, the microfibrils are aggregates of 'elementary fibrils', which have been suggested to be about 3.5 nm in diameter. Solid-state NMR spectroscopy was used to examine two celluloses whose fibril diameters had been established by electron microscopy: onion (8-10 nm, but containing 40% of xyloglucan as well as cellulose) and quince (2 nm cellulose core). Both of these forms of cellulose contained crystalline units of similar size, as estimated from the ratio of surface to interior chains, and the time required for proton magnetisation to diffuse from the surface to the interior. It is suggested that the onion microfibrils must therefore be constructed from a number of cellulose subunits 2 nm in diameter, smaller than the 'elementary fibrils' envisaged previously. The size of these subunits would permit a hexagonal arrangement resembling the cellulose synthase complex.

Solid-state nuclear magnetic resonance relaxation experiments can provide information on the rigidity of individual molecules within a complex structure such as a cell wall, and thus show how each polymer can potentially contribute to the rigidity of the whole structure. We measured the proton magnetic relaxation parameters T2 (spin-spin) and T1p (spin-lattice) through the 13C-nuclear magnetic resonance spectra of dry and hydrated cell walls from onion (Allium cepa L.) bulbs. Dry cell walls behaved as rigid solids. The form of their T2 decay curves varied on a continuum between Gaussian, as in crystalline solids, and exponential, as in more mobile materials. The degree of molecular mobility that could be inferred from the T2 and T1p decay patterns was consistent with a crystalline state for cellulose and a glassy state for dry pectins. The theory of composite materials may be applied to explain the rigidity of dry onion cell walls in terms of their components. Hydration made little difference to the rigidity of cellulose and most of the xyloglucan shared this rigidity, but the pectic fraction became much more mobile. Therefore, the cellulose/xyloglucan microfibrils behaved as solid rods, and the most significant physical distinction within the hydrated cell wall was between the microfibrils and the predominantly pectic matrix. A minor xyloglucan fraction was much more mobile than the microfibrils and probably corresponded to cross-links between them. Away from the microfibrils, pectins expanded upon hydration into a nonhomogeneous, but much softer, almost-liquid gel. These data are consistent with a model for the stress-bearing hydrated cell wall in which pectins provide limited stiffness across the thickness of the wall, whereas the cross-linked microfibril network provides much greater rigidity in other directions.