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Aims: We aimed to examine the benefits of catheter ablation in patients with non-paroxysmal atrial fibrillation (AF) accompanied by heart failure (HF) with preserved ejection fraction (HFpEF), in comparison with the benefits in patients with AF accompanied by HF with reduced ejection fraction (HFrEF) or patients with no HF., Methods and Results: From 1173 consecutive patients undergoing catheter ablation, 502 with non-paroxysmal AF were divided into three groups: no history of HF [plasma B-type natriuretic peptide (BNP) <100 pg/mL and no HF hospitalization; n = 125], HFpEF [left ventricular (LV) EF ≥50%; n = 293], and HF with midrange EF (HFmrEF) + HFrEF (LVEF <50%; n = 84) groups. The endpoints were AF recurrence at 1 year, changes in symptomatic and image-based functional status, and changes in BNP levels from baseline to 1 year. In the HFpEF group, AF recurred in 48 patients (16.4%) and 278 patients (94.8%) had sinus rhythm at 1 year; these values were comparable with those in the other groups. Significant improvement was observed in the left atrial diameter, LVEF, and New York Heart Association functional class in the HFpEF and HFmrEF + HFrEF groups. The BNP level significantly decreased irrespective of the index rate control status, and freedom from AF recurrence was an independent predictor of HF remission, defined as BNP <100 pg/mL at 1 year, in the HFpEF group., Conclusion: Catheter ablation is highly feasible for restoring sinus rhythm in non-paroxysmal AF with coexisting HFpEF, thereby improving cardiac function and BNP levels. Catheter ablation for AF may be an optional management strategy., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2021. For permissions, please email: journals.permissions@oup.com.)

Placozoans, nonbilaterian animals with the simplest known metazoan bauplan, are currently classified into 20 haplotypes belonging to three genera, Polyplacotoma, Trichoplax, and Hoilungia. The latter two comprise two and five clades, respectively. In Trichoplax and Hoilungia, previous studies on six haplotypes belonging to four different clades have shown that their mtDNAs are circular chromosomes of 32-43 kb in size, which encode 12 protein-coding genes, 24 tRNAs, and two rRNAs. These mitochondrial genomes (mitogenomes) also show unique features rarely seen in other metazoans, including open reading frames (ORFs) of unknown function, and group I and II introns. Here, we report seven new mitogenomes, covering the five previously described haplotypes H2, H17, H19, H9, and H11, as well as two new haplotypes, H23 (clade III) and H24 (clade VII). The overall gene content is shared between all placozoan mitochondrial genomes, but genome sizes, gene orders, and several exon-intron boundaries vary among clades. Phylogenomic analyses strongly support a tree topology different from previous 16S rRNA analyses, with clade VI as the sister group to all other Hoilungia clades. We found small inverted repeats in all 13 mitochondrial genomes of the Trichoplax and Hoilungia genera and evaluated their distribution patterns among haplotypes. Because Polyplacotoma mediterranea (H0), the sister to the remaining haplotypes, has a small mitochondrial genome with few small inverted repeats and ORFs, we hypothesized that the proliferation of inverted repeats and ORFs substantially contributed to the observed increase in the size and GC content of the Trichoplax and Hoilungia mitochondrial genomes., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

Guanine is the most easily oxidized of the four DNA bases, and contiguous guanines (GG) in a sequence are more readily oxidized than a single guanine in a sequence. Continued oxidation of GGs results in a contiguous oxidized guanine lesion. Two contiguous 2,5-diamino-4H-imidazol-4-ones, an oxidized form of guanine that hydrolyses to 2,2,4-triamino-5(2H)-oxazolone (Oz), are detected following the oxidation of GG. In this study, we analysed translesion synthesis (TLS) across two contiguous Oz molecules (OzOz) using Klenow Fragment exo(-) (KF exo(-)) and DNA polymerases (Pols) α, β, ζ, η, ι, κ and REV1. We found that KF exo(-) and Pols α, β, ι and REV1 inserted one nucleotide opposite the 3' Oz of OzOz and stalled at the subsequent extension, and that Pol κ incorporated no nucleotide. Pol η only inefficiently elongated the primer up to full-length across OzOz; the synthesis of most DNA strands stalled at the 3' or 5' Oz of OzOz. Surprisingly, however, Pol ζ efficiently extended the primer up to full-length across OzOz, unlike the other DNA polymerases, but catalysed error-prone nucleotide incorporation. We therefore believe that Pol ζ is required for efficient TLS of OzOz. These results show that OzOz obstructs DNA synthesis by DNA polymerases except Pol ζ., (© The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society.)

Purpose: To conduct a national survey of systemic lupus erythematosus (SLE) patients treated with mycophenolate mofetil (MMF). Based on current information on the use of MMF, we aimed to evaluate its efficacy and safety for childhood-onset (c-) SLE., Target: We evaluated 115 patients by questionnaire on MMF use for c-SLE in medical facilities specializing in pediatric rheumatic and renal diseases., Results: Average age at SLE onset was 10.6 (range, 2-15) years; average age at the time of starting MMF was 12.3 (range, 2-15) years. Average dose per body surface area was 1,059.3 mg/m(2)/day. Corticosteroid dosing was 20.9 mg/day before treatment but 7.7 mg/day after treatment. Laboratory values before and after MMF treatment were as follows: C3 increased from 67.0 to 84.9 mg/dl (p < 0.001), C4 increased from 10.2 to 15.1 mg/dl (p < 0.001), and anti-DNA antibody decreased from 154.2 to 18.4 IU/ml (p < 0.001). 24 adverse events in 21 cases were reported, but MMF was not discontinued in any., Conclusions: The amount of MMF for c-SLE in Japan is similar to the standard dose in other countries. Reduction of corticosteroid dose and improvement of laboratory values represent efficacy of MMF. The side effects recorded here indicated tolerability of the drug.

Histatins are salivary proteins found and expressed in human salivary glands. They play a role in the non-immune system of antimicrobial defense, for instance, against Candida albicans. The transcriptional regulatory sequences of the histatin gene, HIS1, have remained obscure for a long time. Here, we cloned the putative promoter from human genomic DNA and tested it in a luciferase reporter system. This promoter is much more active in salivary gland cells than in other cell types. Analysis of deletion mutants revealed that the region encompassing -2254 to -1748 is a strong positive transcriptional element, and its functional core sequence (termed HTN27 box) works in correct and reverse orientations in synergy with downstream sequences, the region spanning -680 to +28 and a proximal promoter. The plus single-stranded HTN27 box is specifically bound by a 100 kDa protein that is present in HSG cells, but not in HeLa cells. These findings indicate that the regulation of the histatin gene expression may be intricate, and it seems to have a cell-type preference in the salivary gland cells.

8-Oxoguanine is the typical oxidative product, but 8-oxoguanine is further oxidized by several oxidizing agents. Here, we investigated the oxidation of 2'-deoxy-8-oxoguanosine with aqueous iodine.

Metabolic manipulation of plants to improve their nutritional quality is an important goal of plant biotechnology. Expression in rice (Oryza sativa L.) of a transgene (OASA1D) encoding a feedback-insensitive alpha subunit of rice anthranilate synthase results in the accumulation of tryptophan (Trp) in calli and leaves. It is shown here that the amount of free Trp in the seeds of such plants is increased by about two orders of magnitude compared with that in the seeds of wild-type plants. The total Trp content in the seeds of the transgenic plants was also increased. Two homozygous lines, HW1 and HW5, of OASA1D transgenic rice were generated for characterization of agronomic traits and aromatic metabolite profiling of seeds. The marked overproduction of Trp was stable in these lines under field conditions, although spikelet fertility and yield, as well as seed germination ability, were reduced compared with the wild type. These differences in agronomic traits were small, however, in HW5. In spite of the high Trp content in the seeds of the HW lines, metabolic profiling revealed no substantial changes in the amounts of other phenolic compounds. The amount of indole acetic acid was increased about 2-fold in the seeds of the transgenic lines. The establishment and characterization of these OASA1D transgenic lines have thus demonstrated the feasibility of increasing the Trp content in the seeds of rice (or of other crops) as a means of improving its nutritional value for human consumption or animal feed.

A method for quantifying indole-3-acetic acid (IAA) and its conjugates with the six amino acids, Ala, -Asp, -Ile, -Glu, -Phe and -Val, in rice (Oryza sativa) by using high-performance liquid chromatography coupled with electrospray ionization and tandem mass spectrometry (HPLC-ESI-MS/MS) is described. Samples from the rice plant or callus were treated with 80% acetone in water containing 2.5 mM diethyl dithiocarbamate. Each extract was partially purified in C18 cartridge column for solid-phase extraction (SPE) and subjected to HPLC-ESI-MS/MS without converting the product. The detection limit was 3.8 fmol for IAA, and 0.4-2.9 fmol for the IAA amino acid conjugates. The method was applied to the analysis of IAA and its conjugates in rice seedlings, dehulled rice and calli, using 20-100 mg tissue samples.

The profile of aromatic metabolites in calli was compared between wild-type rice (Oryza sativa cv. Nipponbare) and tryptophan-overproducing transgenic rice lines that express a gene (OASA1D) for a feedback-insensitive alpha subunit of anthranilate synthase. Metabolic profiling by high-performance liquid chromatography coupled with photodiode array detection of ultraviolet absorbance revealed a total of 71 peaks in both wild-type and transgenic calli. Only a limited effect on the pattern of major aromatic compounds was observed in tryptophan-accumulating transgenic rice lines, with the exception of an approximately 80-fold increase in the amount of tryptophan. Expression of OASA1D induced relatively small changes in several minor metabolites. One of the minor metabolites whose abundance was increased by OASA1D expression was purified and identified as a previously unknown indole-alkaloid glucoside. The levels of free and conjugated forms of indole-3-acetic acid (IAA), a plant hormone derived from the tryptophan biosynthetic pathway, were determined separately by liquid chromatography and tandem mass spectrometry (LC-MS/MS). The amounts of both free IAA and its conjugates were increased in the transgenic calli, suggesting that the activity of anthranilate synthase or the concentration of tryptophan (or both) is an important determinant of IAA biosynthesis.

Deficiency of osteoprotegerin (OPG), a soluble decoy receptor for receptor activator of nuclear factor-kappaB ligand (RANKL), in mice induces osteoporosis caused by enhanced bone resorption, but also accelerates bone formation. We examined whether bone formation is coupled with bone resorption in OPG-deficient (OPG-/-) mice using risedronate, an inhibitor of bone resorption. Histomorphometric analysis showed that bone formation-related parameters (e.g. mineral apposition rate and osteoblast surface/bone surface) in OPG-/- mice sharply decreased with suppression of bone resorption by daily injection of risedronate for 30 d. OPG-/- mice exhibited high serum alkaline phosphatase activity and osteocalcin concentration, both of which were decreased to the levels in wild-type mice by the risedronate injection. Serum levels of RANKL were markedly elevated in OPG-/- mice, but were unaffected by risedronate. The ectopic bone formation induced by bone morphogenetic protein-2 implantation into OPG-/- mice was not accelerated even with a high turnover rate of bone, but attenuation of mineral density from the ectopic bone was more pronounced than that in wild-type mice. These results suggest that bone formation is coupled with bone resorption at local sites in OPG-/- mice, and that serum RANKL levels do not reflect this coupling.

DNA polymerase epsilon is essential for cell viability and chromosomal DNA replication in budding yeast. In addition, DNA polymerase epsilon may be involved in DNA repair and cell-cycle checkpoint control. The enzyme consists of at least four subunits in mammalian cells as well as in yeast. The largest subunit of DNA polymerase epsilon is responsible for polymerase activity. To date, the functions of the other subunits have remained unknown. With a view to elucidating the functions of the second largest subunit of mouse DNA polymerase epsilon (DPE2), yeast two-hybrid screening was performed to identify mouse proteins that interact with this subunit. SAP18, a polypeptide associated with co-repressor protein Sin3, was identified as an interacting protein. A part of the N-terminal region of DPE2 (comprising amino acids 85-250) was found to be responsible for the interaction with SAP18. The interaction induced repression of transcription in reporter plasmid assays, which was inhibited by trichostatin A. These results indicate that DPE2 may recruit histone deacetylase (HDAC) to the replication fork to modify the chromatin structure.

We have isolated the genomic DNA fragment spanning the 5-end and the first four exons encoding the 68 kDa subunit (p68) of the mouse DNA polymerase alpha-primase complex [corrected]. The p68 promoter region lacks TATA and CAAT boxes, but contains a GC-rich sequence, two palindrome sequences and two putative E2F-binding sites [corrected]. A series of transient expression assays using a luciferase reporter gene indicated that a region from nucleotide position -89 to -30 (-89/-30) with respect to the transcription initiation site is crucial for basal transcription of the p68 gene in proliferating NIH 3T3 cells. In particular, part of the GC-rich sequence (-57/-46) and the palindrome (-81/-62) elements were necessary for promoter activity, both of which share homology with the E-box sequence. Gel mobility shift assays using NIH 3T3 nuclear extracts revealed that the upstream stimulatory factor, known as an E-box-binding protein, binds to these sites. Moreover, we observed binding of E2F to two sites near the transcription initiation site (-11/-3 and +9/+16). A transient luciferase expression assay using synchronized NIH 3T3 cells in G(0)phase revealed that these E2F sites are essential for transcription induction of the p68 gene after serum stimulation, but are dispensable for basal transcription. These results indicate that growth-dependent regulation of transcription of the mouse p68 and p180 genes is mediated by a common factor, E2F; however, basal transcription of the genes, interestingly, is regulated by different transcription factors.

A complementary DNA encoding DNA-dependent ATPase Q1 possessing DNA helicase activity, which is the major DNA-dependent ATPase in human cell extracts, was cloned from a cDNA library of human KB cells. The predicted amino acid sequence has seven consecutive motifs conserved in the RNA and DNA helicase super family and DNA helicase Q1 belongs to DEXH helicase family. A homology search indicated that helicase Q1 had 47% homology in the seven conserved regions with Escherichia coli RecQ protein. Three RNA bands of 4.0, 3.3, and 2.2 kilobases were detected in HeLa cells by Northern blotting. Analysis of the genomic DNA indicated the presence of a homologous gene in mouse cells. The DNA helicase Q1 gene was localized on the short arm of human chromosome 12 at 12p12.

The Drosophila melanogaster gene and cDNA which span the entire open reading frame for DNA polymerase alpha, were cloned, and their nucleotide sequences were determined. The gene consists of 6 exons separated by 5 short introns. The major transcription initiation site was localized 85 bp upstream from the initiation codon. The nucleotide sequence of the open reading frame revealed a polypeptide of 1,505 amino acid residues with a molecular weight of 170,796. The amino acid sequence of the polypeptide was 37% homologous with that of the catalytic subunit of human DNA polymerase alpha. This sequence contains six regions, the orders and amino acid sequences of which are highly conserved among a number of other viral and eukaryotic DNA polymerases. We found 7 amino acid residues in the region between the 639th and 758th positions, identical to those essential for the active site of Escherichia coli DNA polymerase I-associated 3'----5' exonuclease. Thus, the exonuclease activity may be associated with Drosophila DNA polymerase alpha. Levels of the DNA polymerase alpha mRNA were high in unfertilized eggs and early embryos, relatively high in adult female flies and second-instar larva, and low in bodies at other stages of development. This feature of the expression is similar to that of the proliferating cell nuclear antigen (an auxiliary protein of DNA polymerase delta) and seems to coincide with the proportions of proliferating cells in various developmental stages. As the half life of the mRNA for DNA polymerase alpha in cultured Drosophila Kc cells was 15 min, expression of the DNA polymerase alpha gene is probably strictly regulated at the step of transcription.