This study aimed to define the width and length of the dental arch in 12-year-old Vietnamese children, and to elucidate differences between genders and among ethnic groups. A cross-sectional study was conducted in 4565 12 years-old children from the 4 major ethnic groups in Vietnam (Kinh, Muong, Thai, and Tay), with a healthy and full set of 28 permanent teeth that had never had any orthodontic treatment and with no reconstructive materials at the measured points. The mean variables in all subjects were 36.39 mm for upper inter-canine width; 46.88 mm for upper inter-first molar width; 59.43 mm for upper inter-second molar width; 10.41 mm for upper anterior length; 32.15 mm for upper posterior length 1; 45.52 mm for upper posterior length 2; 28.31 mm for lower inter-canine width; 41.63 mm for lower inter-first molar width; 54.57 mm for lower inter-second molar width (LM2W); 7.06 mm for lower anterior length (LAL); 26.87 mm for lower posterior length 1 (LP1L); and 41.29 mm for lower posterior length 2. Significant differences in these parameters between genders were found in all ethnic groups, except for LAL in the Kinh and Thai groups, and LP1L in the Tay group. Significant ethnic differences were also found in almost all parameters except LM2W in both males and females. Taken together, the representative sizes of dental arches of 12-year-old Vietnamese children have been defined. Our data indicate that there are some variations in dental arch dimensions among ethnic groups and between genders.

A set of high-molecular-weight glutenin subunit (HMW-GS) deletion lines were used to investigate the influences of HMW-GS on wheat gluten, and dough properties were investigated using a set of HMW-GS deletion lines. Results showed that HMW-GS deletion significantly decreased the dough stability time, as well as viscoelastic moduli (G′ and G″), compared with the wild type, where the deletion of x-type HMW-GSs (Ax1d, Bx7d, and Dy12d) decreased more than y-type HMW-GSs (By8d and Dy12d). The deletion of HMW-GS significantly decreased HMW-GS contents and increased α-/γ-gliadin contents. A proteomic study showed that the HMW-GS deletion down-regulated the HMW-GS, β-amylase, serpins, and protein disulfide isomerase and up-regulated the LMW-GS, α/γ-gliadin, and α-amylase inhibitor. Meanwhile, HMW-GS deletion significantly decreased contents of β-turn and β-sheet. In addition, less energetically stable disulfide conformations (trans–gauche–gauche and trans–gauche–trans) were abundant in HMW-GS deletion lines. Furthermore, analysis of five HMW-GSs based on amino acid sequences proved that Dx2 and Bx7 had a more stable structure, followed by Ax1, then Dy12, and finally By8.

The effect of high-molecular weight glutenin subunits (HMW-GSs) on gluten polymerization during biscuit making was investigated using a set of HMW-GS deletion lines. Results showed that the deletion of HMW-GSs improved the biscuit quality compared with the wild type (WT), especially in x-type HMW-GS deletion lines. Slight gluten depolymerization was observed during dough mixing, while progressive gluten polymerization occurred during biscuit baking. The deletion of HMW-GSs suppressed the polymerization of glutenin and gliadin compared with the WT during biscuit baking, especially in x-type HMW-GS deletion lines. These actions resulted in less elevation of the intermolecular β-sheet and ordered α-helix and altering the disulfide (SS) conformation to a less stable conformation in HMW-GS deletion lines compared with the WT during baking. Molecular dynamics simulation analysis further demonstrated that x-type HMW-GSs had higher thermal stability compared with y-type HMW-GSs during heating.

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