111 research outputs found

    Quorum-dependent expression of rsmX and rsmY, small non-coding RNAs, in Pseudomonas syringae

    Get PDF
    Pseudomonas syringae pathovars are known to produce N-acyl-homoserine lactones (AHL) as quorum-sensing molecules. However, many isolates, including P. syringae pv. tomato DC3000 (PtoDC3000), do not produce them. In P. syringae, psyI, which encodes an AHL synthase, and psyR, which encodes the transcription factor PsyR required for activation of psyI, are convergently transcribed. In P. amygdali pv. tabaci 6605 (Pta6605), there is one nucleotide between the stop codons of both psyI and psyR. However, the canonical stop codon for psyI in PtoDC3000 was converted to the cysteine codon by one nucleotide deletion, and 23 additional amino acids extended it to a C-terminal end. This resulted in overlapping of the open reading frame (ORF) for psyI and psyR. On the other hand, stop codons in the psyR ORF of P. syringae 7 isolates, including pv. phaseolicola and pv. glycinea, were found. These results indicate that many pathovars of P. syringae have genetically lost AHL production ability by the mutation of their responsible genes. To examine whether PtoDC3000 modulates the gene expression profile in a population-dependent manner, we carried out microarray analysis using RNAs prepared from low- and high-density cells. We found the expressions of rsmX and rsmY remarkably activated in high-density cells. The activated expressions of rsmX and rsmY were confirmed by Northern blot hybridization, but these expressions were abolished in a ΔgacA mutant of Pta6605. These results indicate that regardless of the ability to produce AHL, P. syringae regulates expression of the small noncoding RNAs rsmX/Y by currently unknown quorum-sensing molecules

    Efficient hepatocyte differentiation of primary human hepatocyte-derived organoids using three dimensional nanofibers (HYDROX) and their possible application in hepatotoxicity research

    Get PDF
    Tong Y., Ueyama-Toba Y., Yokota J., et al. Efficient hepatocyte differentiation of primary human hepatocyte-derived organoids using three dimensional nanofibers (HYDROX) and their possible application in hepatotoxicity research. Scientific Reports 14, 10846 (2024); https://doi.org/10.1038/s41598-024-61544-y.Human liver organoids are in vitro three dimensionally (3D) cultured cells that have a bipotent stem cell phenotype. Translational research of human liver organoids for drug discovery has been limited by the challenge of their low hepatic function compared to primary human hepatocytes (PHHs). Various attempts have been made to develop functional hepatocyte-like cells from human liver organoids. However, none have achieved the same level of hepatic functions as PHHs. We here attempted to culture human liver organoids established from cryopreserved PHHs (PHH-derived organoids), using HYDROX, a chemically defined 3D nanofiber. While the proliferative capacity of PHH-derived organoids was lost by HYDROX-culture, the gene expression levels of drug-metabolizing enzymes were significantly improved. Enzymatic activities of cytochrome P450 3A4 (CYP3A4), CYP2C19, and CYP1A2 in HYDROX-cultured PHH-derived organoids (Org-HYDROX) were comparable to those in PHHs. When treated with hepatotoxic drugs such as troglitazone, amiodarone and acetaminophen, Org-HYDROX showed similar cell viability to PHHs, suggesting that Org-HYDROX could be applied to drug-induced hepatotoxicity tests. Furthermore, Org-HYDROX maintained its functions for up to 35 days and could be applied to chronic drug-induced hepatotoxicity tests using fialuridine. Our findings demonstrated that HYDROX could possibly be a novel biomaterial for differentiating human liver organoids towards hepatocytes applicable to pharmaceutical research

    PsyR, a transcriptional regulator in quorum sensing system, binds lux box-like sequence in psyI promoter without AHL quorum sensing molecule and activates psyI transcription with AHL in Pseudomonas syringae pv. tabaci 6605

    Get PDF
    Quorum sensing (QS) is a mechanism for bacterial cell-cell communication using QS signals. N-acyl-homoserine lactones (AHLs), QS signals in Pseudomonas syringae pv. tabaci (Pta) 6605, are synthesized by an AHL synthase (PsyI) and recognized by the cognate transcription factor PsyR. To reveal the role of PsyR in virulence, we generated a psyR mutant and complemented strains of Pta 6605 and found that the psyR mutant is remarkably reduced in AHL production and ability to cause disease and propagate in host tobacco leaves. The phenotypes of complemented strains were restored to that of the wild type (WT). Because the psyR mutant lost nearly all AHL production, we investigated the function of PsyR in the transcription of psyI and production of AHL. Electrophoretic mobility shift assays suggested that the recombinant PsyR protein binds the promoter region of psyI but not psyR without AHL. The addition of AHL did not significantly affect this binding. The binding core sequence of this region was identified as a 20-bp lux box-like sequence. To reveal the function of PsyR and AHL on psyI transcription, we constructed a psyI promoter::lacZYA chimeric reporter gene, and inserted it into the WT and psyI mutant of Pta 6605. beta-galactosidase activity increased in a bacterial density-dependent manner in the WT and also in a psyI mutant after the addition of exogenous AHL. These results indicate that the solo PsyR binds the lux box in the psyI promoter and activates transcription in the concomitant presence of AHL

    Parental legacy and regulatory novelty in Brachypodium diurnal transcriptomes accompanying their polyploidy

    Get PDF
    Polyploidy is a widespread phenomenon in eukaryotes that can lead to phenotypic novelty and has important implications for evolution and diversification. The modification of phenotypes in polyploids relative to their diploid progenitors may be associated with altered gene expression. However, it is largely unknown how interactions between duplicated genes affect their diurnal expression in allopolyploid species. In this study, we explored parental legacy and hybrid novelty in the transcriptomes of an allopolyploid species and its diploid progenitors. We compared the diurnal transcriptomes of representative Brachypodium cytotypes, including the allotetraploid Brachypodium hybridum and its diploid progenitors Brachypodium distachyon and Brachypodium stacei. We also artificially induced an autotetraploid B. distachyon. We identified patterns of homoeolog expression bias (HEB) across Brachypodium cytotypes and time-dependent gain and loss of HEB in B. hybridum. Furthermore, we established that many genes with diurnal expression experienced HEB, while their expression patterns and peak times were correlated between homoeologs in B. hybridum relative to B. distachyon and B. stacei, suggesting diurnal synchronization of homoeolog expression in B. hybridum. Our findings provide insight into the parental legacy and hybrid novelty associated with polyploidy in Brachypodium, and highlight the evolutionary consequences of diurnal transcriptional regulation that accompanied allopolyploidy

    4 か月児をもつ35 歳以上の母親における育児不安とその関連要因―35 歳未満の母親との比較―

    Get PDF
    A questionnaire survey was conducted of 977 mothers who were invited to bring their infant to a 4-month health checkup in City A to compare anxiety about childrearing and related factors between older mothers (aged 35 years or older) and younger mothers (under 35 years old). Univariate analysis was performed to examine the associations of anxiety about childrearing with the following in both age groups: participant characteristics,health status, support received, experience during pregnancy and childrearing, items of a childrearing support checklist, items of the Mother-to-Infant Bonding Scale, Edinburgh Postnatal Depression Scale (EPDS) score,and generalized self-efficacy. Significant factors identified in the univariate analysis were used as independent variables in logistic regression analysis, with anxiety about childrearing as a dependent variable. The following were associated with anxiety about childrearing in older mothers: primipara or multipara; restful sleep; history of professional consultation regarding emotional and psychological issues; and 2 items of the Mother-to-Infant Bonding Scale. Sleep status and mental health status were more strongly associated with anxiety about childrearing in older mothers than in younger mother, and this needs to be considered when supporting those mothers. 4 か月児をもつ35 歳以上の母親の育児不安とその関連要因を、35 歳未満の母親と比較し明らかにするため、A 市の4 か月児健康診査対象児の母親977 名に質問紙調査を行った。年齢2 区分別に、育児不安を従属変数とし、基本属性、健康状態、サポート、妊娠期・育児期の体験、育児支援チェックリスト、赤ちゃんへの気持ち質問票の各項目、エジンバラ産後うつ病質問票(EPDS)得点、特性的自己効力感について、育児不安との単変量解析で有意であった項目を独立変数とした、ロジスティック回帰分析を行った。結果、35 歳以上の母親の育児不安には、初産経産の別や睡眠による休養、心理的・精神的な問題での専門職への相談経験、赤ちゃんへの気持ち質問票の2 項目が関連していた。35 歳未満と比較すると、35 歳以上の母親では特に母親自身の睡眠状況や精神的な健康状態が育児不安と関係しており、これを考慮した上で支援を行う必要がある

    Effect of Saxagliptin on Endothelial Function in Patients with Type 2 Diabetes : A Prospective Multicenter Study

    Get PDF
    The dipeptidyl peptidase-4 inhibitor saxagliptin is a widely used antihyperglycemic agent in patients with type 2 diabetes. The purpose of this study was to evaluate the effects of saxagliptin on endothelial function in patients with type 2 diabetes. This was a prospective, multicenter, interventional study. A total of 34 patients with type 2 diabetes were enrolled at four university hospitals in Japan. Treatment of patients was initially started with saxagliptin at a dose of 5 mg daily. Assessment of endothelial function assessed by flow-mediated vasodilation (FMD) and measurement of stromal cell-derived factor-1α (SDF-1α) were conducted at baseline and at 3 months after treatment with saxagliptin. A total of 31 patients with type 2 diabetes were included in the analysis. Saxagliptin significantly increased FMD from 3.1 ± 3.1% to 4.2 ± 2.4% (P = 0.032) and significantly decreased total cholesterol from 190 ± 24 mg/dL to 181 ± 25 mg/dL (P = 0.002), glucose from 160 ± 53 mg/dL to 133 ± 25 mg/dL (P < 0.001), HbA1c from 7.5 ± 0.6% to 7.0 ± 0.6% (P < 0.001), urine albumin-to-creatinine ratio from 63.8 ± 134.2 mg/g to 40.9 ± 83.0 mg/g (P = 0.043), and total SDF-1α from 2108 ± 243 pg/mL to 1284 ± 345 pg/mL (P < 0.001). These findings suggest that saxagliptin is effective for improving endothelial function

    EGUIDE project and treatment guidelines

    Get PDF
    Aim: Although treatment guidelines for pharmacological therapy for schizophrenia and major depressive disorder have been issued by the Japanese Societies of Neuropsychopharmacology and Mood Disorders, these guidelines have not been well applied by psychiatrists throughout the nation. To address this issue, we developed the ‘Effectiveness of Guidelines for Dissemination and Education in Psychiatric Treatment (EGUIDE)’ integrated education programs for psychiatrists to disseminate the clinical guidelines. Additionally, we conducted a systematic efficacy evaluation of the programs. Methods: Four hundred thirteen out of 461 psychiatrists attended two 1‐day educational programs based on the treatment guidelines for schizophrenia and major depressive disorder from October 2016 to March 2018. We measured the participants’ clinical knowledge of the treatment guidelines using self‐completed questionnaires administered before and after the program to assess the effectiveness of the programs for improving knowledge. We also examined the relation between the participants’ demographics and their clinical knowledge scores. Results: The clinical knowledge scores for both guidelines were significantly improved after the program. There was no correlation between clinical knowledge and participant demographics for the program on schizophrenia; however, a weak positive correlation was found between clinical knowledge and the years of professional experience for the program on major depressive disorder. Conclusion: Our results provide evidence that educational programs on the clinical practices recommended in guidelines for schizophrenia and major depressive disorder might effectively improve participants’ clinical knowledge of the guidelines. These data are encouraging to facilitate the standardization of clinical practices for psychiatric disorders
    corecore