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Atopic dermatitis (AD) is characterized by a T-helper cell type 2 (Th2) inflammatory response leading to skin damage with erythema and edema. Comparative fecal sample analysis has uncovered a strong correlation between AD and Faecalibacterium prausnitzii strain A2-165, specifically associated with butyrate production. Therefore, understanding the functional mechanisms of crucial enzymes in the butyrate pathway, such as 3-hydroxybutyryl-CoA dehydrogenase of A2-165 (A2HBD), is imperative. Here, we have successfully elucidated the three-dimensional structure of A2HBD in complex with acetoacetyl-CoA and NAD + at a resolution of 2.2Å using the PAL-11C beamline (third generation). Additionally, X-ray data of A2HBD in complex with acetoacetyl-CoA at a resolution of 1.9 Å were collected at PAL-XFEL (fourth generation) utilizing Serial Femtosecond Crystallography (SFX). The monomeric structure of A2HBD consists of two domains, N-terminal and C-terminal, with cofactor binding occurring at the N-terminal domain, while the C-terminal domain facilitates dimerization. Our findings elucidate the binding mode of NAD + to A2HBD. Upon acetoacetyl-CoA binding, the crystal structure revealed a significant conformational change in the Clamp-roof domain (root-mean-square deviation of 2.202 Å). Notably, residue R143 plays a critical role in capturing the adenine phosphate ring, underlining its significance in substrate recognition and catalytic activity. The binding mode of acetoacetyl-CoA was also clarified, indicating its lower stability compared to NAD + . Furthermore, the conformational change of hydrophobic residues near the catalytic cavity upon substrate binding resulted in cavity shrinkage from an open to closed conformation. This study confirms the conformational changes of catalytic triads involved in the catalytic reaction and presents a proposed mechanism for substrate reduction based on structural observations.

Kamut sprouts (KaS) contain several biologically active compounds. In this study, solid-state fermentation using Saccharomyces cerevisiae and Latilactobacillus sakei was used to ferment KaS (fKaS-ex) for 6 days. The fKaS-ex showed a 26.3 mg/g dried weight (dw) and 46.88 mg/g dw of polyphenol and the β-glucan contents, respectively. In the Raw264.7 and HaCaT cell lines, the non-fermented KaS (nfKaS-ex) decreased cell viability from 85.3% to 62.1% at concentrations of 0.63 and 2.5 mg/mL, respectively. Similarly, the fKaS-ex decreased cell viability, but showed more than 100% even at 1.25 and 5.0 mg/mL concentrations, respectively. The anti-inflammatory effect of fKaS-ex also increased. At 600 µg/mL, the fKaS-ex exhibited a significantly higher ability to reduce cytotoxicity by suppressing COX-2 and IL-6 mRNA expressions as well as that for IL-1β mRNA. In summary, fKaS-ex exhibited significantly lower cytotoxicity and increased anti-oxidant and anti-inflammatory properties, indicating that fKaS-ex is beneficial for use in food and other industries.

Noninvasive imaging has become the standard for hepatocellular carcinoma (HCC) diagnosis in cirrhotic livers. In this review paper, we go over the basics of MR imaging in cirrhotic livers and describe the imaging appearance of a spectrum of hepatic nodules marking the progression from regenerative nodules to low- and high-grade dysplastic nodules, and ultimately to HCCs. We detail and illustrate the typical imaging appearances of different types of HCC including focal, multi-focal, massive, diffuse/infiltrative, and intra-hepatic metastases; with emphasis on the diagnostic value of MR in imaging these lesions. We also shed some light on liver imaging reporting and data system, and the role of different magnetic resonance imaging (MRI) contrast agents and future MRI techniques including the use of advanced MR pulse sequences and utilization of hepatocyte-specific MRI contrast agents, and how they might contribute to improving the diagnostic performance of MRI in early stage HCC diagnosis.

Background: The thioredoxin system maintains redox balance through the action of thioredoxin and thioredoxin reductase. Thioredoxin regulates the activity of various substrates, including those that function to counteract cellular oxidative stress. These include the peroxiredoxins, methionine sulfoxide reductase A and specific transcription factors. Of particular relevance is Redox Factor-1, which in turn activates other redox-regulated transcription factors., Scope of Review: Experimentally defined transcription factor binding sites in the human thioredoxin and thioredoxin reductase gene promoters together with promoters of the major thioredoxin system substrates involved in regulating cellular redox status are discussed. An in silico approach was used to identify potential putative binding sites for these transcription factors in all of these promoters., Major Conclusions: Our analysis reveals that many redox gene promoters contain the same transcription factor binding sites. Several of these transcription factors are in turn redox regulated. The ARE is present in several of these promoters and is bound by Nrf2 during various oxidative stress stimuli to upregulate gene expression. Other transcription factors also bind to these promoters during the same oxidative stress stimuli, with this redundancy supporting the importance of the antioxidant response. Putative transcription factor sites were identified in silico, which in combination with specific regulatory knowledge for that gene promoter may inform future experiments., General Significance: Redox proteins are involved in many cellular signalling pathways and aberrant expression can lead to disease or other pathological conditions. Therefore understanding how their expression is regulated is relevant for developing therapeutic agents that target these pathways., (© 2013.)

The 'art' genes encode specific arginine uptake proteins, and are repressed by the repressible promoters of ArgR, affecting transcription of artJ. Cpb0502, the arginine-binding periplasmic protein 2 precursor from Chlamydophila pneumoniae TW-183 strains, is responsible for arginine transport. As C. pneumoniae is difficult to isolate and culture, there have been many studies of better ways to detect it. A microimmunofluorescence assay (MIF) is still considered to be the 'gold standard' for detecting C. pneumoniae. Although MIF has its own limitations, a number of immunogenic antigens have been shown to be C. pneumoniae specific by this test. Here, we report Cpb0502 as a specific immunogenic antigen against C. pneumoniae as it was detected only in human infection sera of C. pneumoniae but not in Legionella pneumophila and Mycoplasma pneumoniae infection sera, showing high specificity and sensitivity by MIF, western blot and ELISA analysis. And also the crystal structure of Cpb0502 was determined to be a dimer at 2.07Å, revealing a similar backbone structure to a histidine kinase receptor, HK29S. Therefore we may suggest that Cpb0502 is a candidate immunogenic antigen for better diagnosis of C. pneumoniae., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Thioredoxin is a redox-active protein that plays multiple roles in regulating cell growth, cell signalling and apoptosis. Here, we have demonstrated that a complex mechanism involving multiple regulatory elements is involved in the tBHQ [tert-butylhydroquinone or 2,5-di-(t-butyl)-1,4-hydroquinone]-mediated activation of the thioredoxin gene. Luciferase assays, utilizing various wild-type and mutated thioredoxin promoter fragments, revealed roles for the ORE (oxidative stress responsive element), ARE (antioxidant responsive element), three Sp1 (specificity protein 1)-binding sites and the TATA box in the activation of the thioredoxin gene by tBHQ. The ORE required the presence of the ARE to elicit its response, whereas the independent removal of three Sp1-binding sites and the TATA box also decreased activation of the thioredoxin gene, with mutation of the TATA box having the greatest effect. Real-time RT (reverse transcriptase)-PCR analysis also revealed varying roles for two TSSs (transcription start sites) in the activation of the thioredoxin gene by tBHQ. Transcription was initiated from both TSSs; however, different response rates and fold inductions were observed. Together, these results suggest that the thioredoxin gene is controlled by a novel arrangement of two overlapping core promoter regions, one containing a TATA box and the other TATA-less. Altering the intracellular levels of thioredoxin in a breast cancer cell line also influenced the induction of thioredoxin transcription in response to tBHQ. Stable transfections with a redox-inactive thioredoxin mutant produced 3.6 times higher induction levels of thioredoxin transcription compared with control cells, indicating an intrinsic form of control of promoter activity by the thioredoxin system itself.