The sterilized, freeze-dried AM retained most of the physical, biological, and morphologic characteristics of cryopreserved AM; consequently, it is a useful biomaterial for ocular surface reconstruction.

DNA polymerase g (Polg), whose gene mutation is responsible for the inherited disorder xeroderma pigmentosum variant (XP-V), carries out accurate and efficient translesion synthesis (TLS) across cyclobutane pyrimidine dimer (CPD). As Polg interacts with REV1, and REV1 interacts with other TLS polymerases including Poli, Polj and Polf, Polg may play a role in recruitment of these TLS polymerases at lesion site. But it is unclear whether UV sensitivity of XP-V patients is caused not only by defect of Polg activity but also by dysfunction of network between Polg and other TLS polymerases. Here, we examined whether the TLS polymerase network via Polg is important for replicative bypass of CPDs and DNA damage tolerance induced by UV in mouse cells. We observed that UV sensitivity of Polg-deficient mouse cells was moderately rescued by the expression of a catalytically inactive Polg. Moreover, this recovery of cellular UV sensitivity was mediated by the interaction between Polg and REV1. However, expression of the inactive mutant Polg was not able to suppress the incidence of UV-induced mutation observed in Polg-deficient cells. We propose the model that REV1 and Polj are involved in DNA damage tolerance via Polg-REV1 interaction when Polg fails to bypass its cognate substrates.

Background PQBP1 is a causative gene for X-linked mental retardation (MR) whose patients frequently show lean body. C. elegans has a strictly conserved homologue gene of PQBP1, T21D12.3.Methodology and Principal FindingsWe generated Venus-transgenic and T21D12.3-mutant nematodes to analyze developmental expression patterns and in vivo functions of the nematode PQBP1 homologue protein (pqbp-1.1). During development, pqbp-1.1 is expressed from cell proliferation stage to larva stage. In larva, intestinal cells show the highest expression of pqbp-1.1, while it decreases in adult worms. The mutants of pqbp-1.1 show a decrease of the lipid content in intestinal cells. Especially, incorporation of fatty acid into triglyceride is impaired. ShRNA-mediated repression of PQBP1 also leads to reduction of lipid content in mammalian primary white adipocytes.Conclusion/ SignificanceThese results suggest that pqbp-1.1 is involved in lipid metabolism of intestinal cells. Dysfunction of lipid metabolism might underlie lean body, one of the most frequent symptoms associating with PQBP1-linked MR patients.

Despite the important role of oral texture perception in feeding and nutritional homeostasis, its impairment has not been of particular clinical interest, and no clinical protocol is available to evaluate its acuity. This preliminary study aimed to establish a method to evaluate the acuity of oral texture perception. Because texture perception is regarded as reflecting integrity of the sensorimotor system of the jaw and mouth, we hypothesized that the ability to perceive various aspects of food texture would correlate with each other, and tested our hypothesis in 11 healthy adults. First, we prepared three types of test foods with different dominant textures, each of which comprised a series of stimuli with different ingredient concentrations; we used these test foods in discrimination tests involving pairwise comparison. Tests performed using the up‐down staircase method revealed significant correlation among the discrimination thresholds for three test foods, suggesting that acuities of texture perception correlated with each other across different textural attributes. Second, we examined the associations between the acuity of texture perception and some aspects of mechanical sensation of the tongue: tactile and two‐point discrimination thresholds, as well as the graininess recognition threshold. The acuity of texture perception of the subjects whose sensitivity was low for at least one of these aspects of mechanical sensation (n = 5) was significantly lower than that exhibited by the other subjects (Wilcoxon rank‐sum test, p = 0.0417). We concluded that oral texture perception ability can be evaluated by discrimination tests for specific aspects of texture, using appropriate test foods.

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