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Abstract An aspartate:alanine antiporter (AspT) from the lactic acid bacterium Tetragenococcus halophilus catalyzes the electrogenic aspartate1-:alanine0 exchange reaction. Our previous kinetic analyses of transport reactions mediated by AspT in reconstituted liposomes suggested that, although the substrate transport reactions are physiologically coupled, the putative binding sites of l-aspartate (-Asp) and l-alanine (-Ala) are independently located on AspT. By using the fluorescent probe Oregon Green maleimide (OGM), which reacts specifically with cysteine, we also found that the presence of l-Asp changes the conformation of AspT. In this study, we conducted an OGM labeling assay in the presence of l-Ala. The labeling efficiency of single cysteine mutants (G62C and P79C) in transmembrane helix 3 of the AspT showed novel patterns depending on the presence of l-Ala or analogs. A concentration-dependent shift of AspT from the conformation in the presence of one substrate to that specific to the substrate added subsequently (l-Ala or l-Asp) was observed. Moreover, size-exclusion-chromatography-based thermostability assays indicated that the thermal stability of AspT in the presence of l-Ala differed from that in the presence of l-Asp. From these results, we concluded that l-Ala binding yields a conformation different from the apo or l-Asp binding conformations.

Subcutaneous space has been considered an attractive site for islet graft transplantation; however, the oxygen tension and vascularization are insufficient for islet graft survival. We investigated whether subcutaneous pre-implantation of a recombinant peptide (RCP) device with adipose tissue-derived stem cells (ADSCs) enhanced subcutaneous islet engraftment. RCP devices with/without syngeneic ADSCs were pre-implanted into the subcutaneous space of C57BL/6 mice. Syngeneic islets (300 or 120 islet equivalents (IEQs)) were transplanted into the pre-treated space after diabetes induction using streptozotocin. The cure rates of groups in which RCP devices were implanted four weeks before transplantation were significantly better than the intraportal transplantation group when 300 IEQs of islets were transplanted (p < 0.01). The blood glucose changes in the RCP+ADSCs-4w group was significantly ameliorated in comparison to the RCP-4w group when 120 IEQs of islets were transplanted (p < 0.01). Immunohistochemical analyses showed the collagen III expression in the islet capsule of the RCP+ADSCs-4w group was significantly enhanced in comparison to the RCP-4w and RCP+ADSCs-d10 groups (p < 0.01, p < 0.01). In addition, the number of von Willebrand factor-positive vessels within islets in the RCP+ADSCs-4w group was significantly higher than the RCP-4w group. These results suggest that using ADSCs in combination with an RCP device could enhance the restoration of the extracellular matrices, induce more efficient prevascularization within islets, and improve the graft function.

The demand for skin-whitening agents is high across the world, including Asian countries. An extensive screening using a tyrosinase inhibition assay was performed in order to discover novel plant materials. In our research program investigating a safe and effective agent, 50% ethanolic extracts prepared from discarded parts of Prunus persica were screened for in vitro tyrosinase inhibitory activity. Among the extracts tested, twig extract showed the most potent inhibitory activity: 38% inhibition at 500 µg/mL. The investigation of active compounds in twig extract found four flavanones that acted as moderate inhibitors, including (−)-prunin, persiconin, (+)-dihydrokaempferol, and (−)-naringenin. These compounds were only observed in the twig extract following preliminary quantification by HPLC, with the following concentrations: (−)-prunin, 1.8 mg/g sample; persiconin, 0.8 mg/g sample; (+)-dihydrokaempferol, 0.8 mg/g sample; (−)-naringenin, 1.7 mg/g sample. These results suggest that twig extracts can be more useful for skin-whitening compared with other parts of the plant. In addition, a new constituent of twig extract was identified, namely isoquercitrin, which suggests that twig extract can be a potent source of flavones and flavanones. Further studies on the identification of novel compounds from twig extract are now underway in our laboratory.

Sensitive and label-free imaging methods to visualize nerve degeneration are currently lacking. Here authors show that stimulated Raman scattering (SRS) microscopy can be used to monitor peripheral nerve degeneration in mouse models of amyotrophic lateral sclerosis (ALS) and in postmortem tissue from ALS patients.

Cell-free protein synthesis is a powerful method to explore the structure and function of membrane proteins and to analyze the targeting and translocation of proteins across the ER membrane. Developing a cell-free system based on cultured cells for the synthesis of membrane proteins could provide a highly reproducible alternative to the use of tissues from living animals. We isolated Sf21 microsomes from cultured insect cells by a simplified isolation procedure and evaluated the performance of the translocation system in combination with a cell-free translation system originating from the same source. The isolated microsomes contained the basic translocation machinery for polytopic membrane proteins including SRP-dependent targeting components, translocation channel (translocon)-dependent translocation, and the apparatus for signal peptide cleavage and N-linked glycosylation. A transporter protein synthesized with the cell-free system could be functionally reconstituted into a lipid bilayer. In addition, single and double labeling with non-natural amino acids could be achieved at both the lumen side and the cytosolic side in this system. Moreover, tail-anchored proteins, which are post-translationally integrated by the guided entry of tail-anchored proteins (GET) machinery, were inserted correctly into the microsomes. These results showed that the newly developed cell-free translocation system derived from cultured insect cells is a practical tool for the biogenesis of properly folded polytopic membrane proteins as well as tail-anchored proteins.

Subcutaneous space has been considered an attractive site for islet graft transplantation; however, the oxygen tension and vascularization are insufficient for islet graft survival. We investigated whether subcutaneous pre-implantation of a recombinant peptide (RCP) device with adipose tissue-derived stem cells (ADSCs) enhanced subcutaneous islet engraftment. RCP devices with/without syngeneic ADSCs were pre-implanted into the subcutaneous space of C57BL/6 mice. Syngeneic islets (300 or 120 islet equivalents (IEQs)) were transplanted into the pre-treated space after diabetes induction using streptozotocin. The cure rates of groups in which RCP devices were implanted four weeks before transplantation were significantly better than the intraportal transplantation group when 300 IEQs of islets were transplanted (p < 0.01). The blood glucose changes in the RCP+ADSCs-4w group was significantly ameliorated in comparison to the RCP-4w group when 120 IEQs of islets were transplanted (p < 0.01). Immunohistochemical analyses showed the collagen III expression in the islet capsule of the RCP+ADSCs-4w group was significantly enhanced in comparison to the RCP-4w and RCP+ADSCs-d10 groups (p < 0.01, p < 0.01). In addition, the number of von Willebrand factor-positive vessels within islets in the RCP+ADSCs-4w group was significantly higher than the RCP-4w group. These results suggest that using ADSCs in combination with an RCP device could enhance the restoration of the extracellular matrices, induce more efficient prevascularization within islets, and improve the graft function. [ABSTRACT FROM AUTHOR]

Because of computational advances in reservoir simulation with high-performance computing, it is now possible to simulate more than thousands of reservoir-simulation cases in a practical time frame. This opens a new avenue to reservoir-simulation studies, enabling exhaustive exploration of subsurface uncertainty and development/depletion options. However, analyzing the results of a large number of simulation cases still remains a challenging and overwhelming task. We propose a new method that enables the efficient analysis of massive reservoir-simulation results, often consisting of thousands of cases, by discovering interesting patterns of relationships among variables in large data sets. The method uses a well-known data-mining method, called association-rule mining, together with a high-dimensional visualization technique. We demonstrate the capability of the proposed method by using it to analyze the reservoir-simulation results from the Sensitivity Analysis of the Impact of Geological Uncertainty on Production (SAIGUP) project, which is an interdisciplinary reservoir-modeling project carried out earlier by Manzocchi et al. (2008a). To investigate the influence of geological features on oil recovery in shallow marine reservoirs, numerous reservoir models were built and flow-simulated in the SAIGUP project. In this paper, we analyze the simulation results from an ensemble of 9,072 models, which cover all possible combinations of several structural and sedimentological parameters individually varied to describe geological uncertainty. To be able to analyze the simulation results from such exhaustive sampling from high-dimensional model parameter space, it is crucial to efficiently decompose complex interactions between model parameters and to discover hidden impacts on flow response. By coupling the association-rule mining algorithm and high-dimensional visualization, such interactions and impacts are rapidly extracted and visualized in such a way that engineers and geoscientists can interpret meaningful sensitivities "at a glance." This methodology provides a novel way to rapidly interpret flow response from a large ensemble of reservoir models without being overwhelmed by massive data. [ABSTRACT FROM AUTHOR]

The article reports a study on the loss-of-function mutation in mouse models with amyotrophic lateral sclerosis, frontotemporal dementia, and mortality from severe autoimmunity. It describes the transplantation of mutant mouse bone marrow into wild-type recipients to recapitulate phenotypes. The researchers conclude that C9ORF72 serves an important function within the hematopoietic system to prevent inflammation and development of autoimmunity.

The article focuses on a study aimed at examining the impact of high-intensity endurance exercise on skin secretory immunoglobulin A and staphylococci. Participants in the study performed the bicycle exercise for one hour. It was found that the endurance exercise led to an increase in the risk of infections on skin surface.

Abstract  Geostatistically based history-matching methods make it possible to devise history-matching strategies that will honor geologic knowledge about the reservoir. However, the performance of these methods is known to be impeded by slow convergence rates resulting from the stochastic nature of the algorithm. It is the purpose of this paper to introduce a method that integrates qualitative gradient information into the probability perturbation method to improve convergence. The potential of the proposed method is demonstrated on a synthetic history-matching example. The results indicate that inclusion of qualitative gradient information improves the performance of the probability perturbation method. [ABSTRACT FROM AUTHOR]

A non-fullerene n-type semiconductor material based on a central benzothiadiazole moiety flanked with octyl-vinylimides (4,7-bis(4-(N-octyl-phthalimide)vinyl)benzo[c]1,2,5-thiadiazole, OPIBT) was synthesized. OPIBT was found to be a liquid crystalline material with a smectic phase. We fabricated a solar cell with a bulk heterojunction structure using OPIBT and poly(3-hexylthiophene-2,5-diyl) as a p-type semiconductor. On comparing it with a solar cell using a compound with a similar skeleton but exhibiting no liquid crystallinity, we found the thermal stability of the OPIBT solar cells to be superior. [ABSTRACT FROM AUTHOR]