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Amylose (AM) and amylopectin (AP) functionality during bread making was unravelled with a temperature-controlled time domain proton nuclear magnetic resonance (TD 1H NMR) toolbox. Fermented doughs from wheat flour containing starches with atypical AP chain length distribution and/or AM to AP ratio, or supplemented with Bacillus stearothermophilus α-amylase (BStA) were analyzed in situ during baking and cooling. The gelatinization temperature of starch logically depended on AP crystal stability. It was lower when starch contained a higher portion of short AP branches and higher when starch had higher AP content. During cooling, the onset temperature and extent of AM crystallization were positively related to starch AM content. BStA use resulted in slightly weakened starch networks and increased the starch polymers' mobility at the end of baking. That proton distributions evolved in a way corresponding to starch characteristics supports the suggested interpretation of NMR profiles during baking and cooling. ispartof: FOOD CHEMISTRY vol:295 pages:110-119 ispartof: location:England status: published

Bread crumb firming is largely determined by the properties of gluten and starch, and the transformations they undergo during bread making and storage. Amylose (AM) and amylopectin (AP) functionality in fresh and stored bread was investigated with NMR relaxometry. Bread was prepared from flours containing normal and atypical starches, e.g., flour from wheat line 5-5, with or without the inclusion of Bacillus stearothermophilus α-amylase. Initial crumb firmness increased with higher levels of AM or shorter AM chains. Both less extended AM and gluten networks and too rigid AM networks led to low crumb resilience. AP retrogradation during storage increased when crumb contained more AP or longer AP branch chains. Shorter AP branch chains, which were present at higher levels in 5-5 than in regular bread, were less prone to retrogradation, thereby limiting gluten network dehydration due to gluten to starch moisture migration. Correspondingly, crumb firming in 5-5 bread was restricted.

•We report 2 patients with pontine infarcts showing transient conjugate eye deviation.•Conjugate eye deviation resolved within a few days in both patients.•Small restricted dorsomedial pontine lesions can produce conjugate eye deviation.

The double mutant "sweet wheat" (SW), which produces substantial amounts of sugars in immature seeds, is missing two starch synthases, namely granule-bound starch synthase I (GBSSI) and starch synthase IIa (SSIIa). The lack of these two enzymes causes major changes in the attributes of SW seed, starch, and starch granules. SW seeds appear normal during early stages of development, but become shrunken when seeds begin to mature and dry. However, even in immature seed, starch granules are small and misshapen, and high levels of maltose are present throughout seed development. The crystallinity of SW starch is altered in that a major peak typical of the cereal A-type diffraction pattern is absent, and the gelatinization temperature of SW starch is considerably lower than that of wild-type starch. Amylopectin from SW seed has a substantially lower molecular weight than that from wild-type seed, and a low molecular weight peak with a bimodal distribution is found only in SW starch. This peak contains linear malto-oligosaccharides as well as short, branched glucans. SW starch has an increased proportion of branches with DP10, and chains with DP 2 and 3 are particularly increased. These changes suggest that sweet wheat starch is being modified in an atypical manner by isoamylases and/or β-amylases.

Perfluorooctanoic acid (PFOA) is a ligand for peroxisome proliferator-activated receptor (PPAR) alpha, which exhibits marked species differences in expression and function, especially between rodents and humans. We investigated the functional difference in PFOA response between mice and humans, using a humanized PPARalpha transgenic mouse line. Three genotyped mice, 129/Sv wild-type (mPPARalpha), Pparalpha-null mice and humanized PPARalpha (hPPARalpha) mice (8-week-old males) were divided into three groups: the first was treated with water daily for 2 weeks by gavage (control group), and the remaining two groups were treated with 0.1 and 0.3mg/kg ammonium perflurooctanate (APFO), respectively, for 2 weeks by gavage. The APFO dosages used did not influence the plasma triglyceride or total cholesterol levels in any mouse line, but the high dose increased both hepatic lipid levels only in mPPARalpha mice. APFO increased mRNA and/or protein levels of PPARalpha target genes cytochrome P450 Cyp4a10, peroxisomal thiolase and bifunctional protein only in the liver of mPPARalpha mice, but not in Pparalpha-null or hPPARalpha mice. This chemical also increased expression of mitochondrial very long chain acyl-CoA dehydrogenase only in the liver of mPPARalpha mice. Taken together, human PPARalpha may be less responsive to PFOA than that of mice when a relatively low dose is applied. This information may be very valuable in considering whether PFOA influences the lipid metabolism in humans.

Maize waxy (Wx) protein, which has been detected as a single protein with a M r 60 000 by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE), was separated into four isoforms by 2D-PAGE. The isoelectric point (p I ) of these isoforms ranged from 6.0 to 6.5. Starch isolation with SDS-buffer and heat-extraction of protein from starch granules had no effect on the 2D electrophoretic patterns of Wx protein. Rice and barley Wx proteins were also analysed by the same method and separated into four and three isoforms, respectively. Rice Wx protein isoforms had a M r of 60 000 as had been reported with a p I range from 6.5 to 7.2 while barley Wx protein isoforms had a M r of 61 000 and p I in the range of 5.8 to 6.3.

Systemically administered 1-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP), a toxin inducing parkinsonism, is biotransformed into 1methyl-4-.phenylpyridinium ion (MPP+), which then enters dopaminergic neurons via the dopamine uptake system to destroy nigral cells.

The structure and mRNA accumulation of T-DNA of Ri (A4) plasmids integrated into the genome of Nicotiana tabacum var. Samsun were investigated. Two inserts of TL-DNA were found in the transformed plant (R1) and one (R2) of the progenies obtained by self-crossing of the R1 plant. The expression level of T-DNA-derived transgenic plants was high in roots and stems, but very low in leaves. The gene encoding the major transcript of integrated Ri TL-DNA coincided with the ORF12 (Slightom et al., J. Biol. Chem., 261 (1986) 108).