Publications by authors named "Jun Ishii"

Purified DNA plasmids traditionally used for microbial transformation have been supplanted by extracellular plasmids released via host bacterial lysis, offering an alternative approach for DNA-plasmid delivery. Specifically, shuttle vector plasmids liberated from host Bacillus subtilis were directly employed for the transformation of chemically competent cells Escherichia coli, eliminating the need for biochemical purification. This unconventional DNA delivery technique, referred to as 'Cell Lysis Technology to provide Transformable Extra-cellular DNA; CELyTED', has been successfully adapted for the transformation of microorganism Saccharomyces cerevisiae as well.

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Microbial production of bicyclic monoterpenes is of great interest because their production primarily utilizes non-sustainable resources. Here, we report an engineered yeast that produces bicyclic monoterpenes, including borneol, camphor, and bornyl acetate. The engineered yeast expresses a bornyl pyrophosphatase synthase from fused with mutated farnesyl pyrophosphate synthase from .

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Recent studies suggest that lung adenocarcinoma cells are closely associated with the tumorigenesis of large-cell neuroendocrine carcinoma via cellular transformation. However, morphological evidence, along with genetic abnormalities before, during, and after transformation, is quite limited. We present here a case of combined large-cell neuroendocrine carcinoma and adenocarcinoma exhibiting acinar and solid patterns.

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Inducible promoters are essential for precise control of target gene expression in synthetic biological systems. However, engineering eukaryotic promoters is often more challenging than engineering prokaryotic promoters due to their greater mechanistic complexity. In this study, we describe a simple and reliable approach for constructing strongly inducible synthetic promoters with minimum leakiness in yeasts.

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Protein-based therapeutics, including antibodies and antibody-like-proteins, have increasingly attracted attention due to their high specificity compared to small-molecular drugs. The Gγ recruitment system, one of the in vivo yeast two-hybrid systems for detecting protein-protein interactions, has been previously developed using yeast signal transduction machinery. In this study, we modified the Gγ recruitment system to screen the protein mutants that efficiently bind to the intracellular domain of the epidermal growth factor receptor L858R mutant (cytoEGFR).

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Article Synopsis
  • * This study involved 163 HCC patients who underwent liver resection, revealing that low preoperative s-CK levels (below 91 U/l) correlated with worse overall and recurrence-free survival rates.
  • * The analysis indicated that low s-CK acts as an independent risk factor for poor survival outcomes, particularly in male patients, suggesting it could serve as a valuable prognostic biomarker for HCC.
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Midkine (MK) is a soluble cytokine, and its serum levels strongly correspond to protein expression levels in tumors. The present study aimed to clarify the clinicopathological and prognostic significance of serum MK (s-MK) in patients with hepatocellular carcinoma (HCC). Serum samples were obtained before surgery from 123 patients with HCC who had undergone surgery between January 2012 and December 2020.

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Background: Single-cell droplet microfluidics is an important platform for high-throughput analyses and screening because it provides an independent and compartmentalized microenvironment for reaction or cultivation by coencapsulating individual cells with various molecules in monodisperse microdroplets. In combination with microbial biosensors, this technology becomes a potent tool for the screening of mutant strains. In this study, we demonstrated that a genetically engineered yeast strain that can fluorescently sense agonist ligands via the heterologous expression of a human G-protein-coupled receptor (GPCR) and concurrently secrete candidate peptides is highly compatible with single-cell droplet microfluidic technology for the high-throughput screening of new agonistically active peptides.

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Overexpression of proteins by introducing a DNA vector is among the most important tools for the metabolic engineering of microorganisms such as Escherichia coli. Protein overexpression imposes a burden on metabolism because metabolic pathways must supply building blocks for protein and DNA synthesis. Different E.

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is a promising host for the bioproduction of higher alcohols, such as 2,3-butanediol (2,3-BDO). Metabolically engineered strains that produce 2,3-BDO via glycolysis have been constructed. However, the specific 2,3-BDO production rates of engineered strains must be improved.

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Background/purpose: To investigate the safety of laparoscopic liver resections (LLRs) for high-risk patients (HRs) with preoperative comorbidities affecting the heart, lungs, kidneys, glucose tolerance, and central nervous system.

Methods: This retrospective study included 585 patients who had undergone total hepatectomies from 2006 to 2020. Among them, 239 patients underwent LLRs, and 349 underwent open liver resections (OLRs).

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Background: "ATP wasting" has been observed in C metabolic flux analyses of Saccharomyces cerevisiae, a yeast strain commonly used to produce ethanol. Some strains of S. cerevisiae, such as the sake strain Kyokai 7, consume approximately two-fold as much ATP as laboratory strains.

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Article Synopsis
  • Hand-assisted laparoscopic surgery (HALS) has emerged as a useful option in laparoscopic liver resection (LLR), but the factors influencing conversion to HALS are not well understood.
  • A study analyzed data from patients undergoing LLR from 2011 to 2020, revealing that conversion to HALS occurred in 11.2% of cases, mainly due to failure to progress during surgery and other complications.
  • The analysis identified that tumors located in segments 7 or 8 are significant predictors for conversion to HALS, which showed comparable outcomes to pure LLR in terms of blood loss, operation time, hospital stay, and severe complications.
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Background: The filamentous fungus Trichoderma reesei has been used as a host organism for the production of lignocellulosic biomass-degrading enzymes. Although this microorganism has high potential for protein production, it has not yet been widely used for heterologous recombinant protein production. Transcriptional induction of the cellulase genes is essential for high-level protein production in T.

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Article Synopsis
  • - A 70-year-old woman diagnosed with metastatic pancreatic tail carcinoma developed Sister Mary Joseph's nodule (SMJN) after undergoing chemotherapy treatment, resulting in deteriorating health and severe anemia.
  • - The patient experienced significant symptoms including bleeding from the umbilical tumor, which impaired her daily activities and required multiple blood transfusions.
  • - A surgical resection of the SMJN was performed to alleviate bleeding and improve quality of life, leading to a successful recovery; however, she passed away 59 days post-surgery, yet lived without pain or bleeding until then.
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Conventional analysis of microbial bioproducers requires the extraction of metabolites from liquid cultures, where the culturing steps are time consuming and greatly limit throughput. To break through this barrier, the current study aims to directly evaluate microbial bioproduction colonies by way of supercritical fluid extraction-supercritical fluid chromatography-triple quadrupole mass spectrometry (SFE-SFC-MS/MS). The online SFE-SFC-MS/MS system offers great potential for high-throughput analysis due to automated metabolite extraction without any need for pretreatment.

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Bioconversion of key intermediate metabolites such as mevalonate into various useful chemicals is a promising strategy for microbial production. However, the conversion of mevalonate into isoprenoids requires a supply of adenosine triphosphate (ATP). Light-driven ATP regeneration using microbial rhodopsin is an attractive module for improving the intracellular ATP supply.

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A light-driven ATP regeneration system using rhodopsin has been utilized as a method to improve the production of useful substances by microorganisms. To enable the industrial use of this system, the proton pumping rate of rhodopsin needs to be enhanced. Nonetheless, a method for this enhancement has not been established.

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Purpose: To evaluate the predictors of a difficult Pringle maneuver (PM) in laparoscopic liver resection (LLR) and to assess alternative procedures to PM.

Methods: Data from patients undergoing LLR between 2013 and 2020 were reviewed retrospectively. Univariate and multivariate analyses were performed and the outcomes of patients who underwent PM or alternative procedures were compared.

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Expression of secreted recombinant proteins burdens the protein secretion machinery, limiting production. Here, we describe an approach to improving protein production by the non-conventional yeast Komagataella phaffii comprised of genome-wide screening for effective gene disruptions, combining them in a single strain, and recovering growth reduction by adaptive evolution. For the screen, we designed a multiwell-formatted, streamlined workflow to high-throughput assay of secretion of a single-chain small antibody, which is cumbersome to detect but serves as a good model of proteins that are difficult to secrete.

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In our previous study, we serendipitously discovered that protein secretion in the methylotrophic yeast Pichia pastoris is enhanced by a mutation (V50A) in the mating factor alpha (MFα) prepro-leader signal derived from Saccharomyces cerevisiae. In the present study, we investigated 20 single-amino-acid substitutions, including V50A, located within the MFα signal peptide, indicating that V50A and several single mutations alone provided significant increase in production of the secreted proteins. In addition to hydrophobicity index analysis, both an unfolded protein response (UPR) biosensor analysis and a microscopic observation showed a clear difference on the levels of UPR induction and mis-sorting of secretory protein into vacuoles among the wild-type and mutated MFα signal peptides.

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Background/aim: Liver X receptors (LXRs) are nuclear receptors with various functions, including the regulation of cholesterol metabolism, glucose homeostasis, and inflammation. We previously reported that LXR activation inhibits the growth of oral cancer cells by inducing cellular cholesterol efflux and that LXRβ is expressed mainly in small-cell lung cancer (SCLC) tissues. SCLC is one of the most aggressive cancers, and identifying an effective therapeutic target molecule is desirable.

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Fermentative production of squalene in yeast as an alternative approach to extracting squalene from sharks or plants has attracted significant interest. However, squalene accumulation is limited due to its inevitable high-flux allocation toward ergosterol synthesis. In this study, we described expression control of squalene monooxygenase (Erg1p), the first-step enzyme of ergosterol synthesis from squalene, to significantly reduce squalene loss.

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Transcriptional switches can be utilized for many purposes in synthetic biology, including the assembly of complex genetic circuits to achieve sophisticated cellular systems and the construction of biosensors for real-time monitoring of intracellular metabolite concentrations. Although to date such switches have mainly been developed in prokaryotes, those for eukaryotes are increasingly being reported as both rational and random engineering technologies mature. In this review, we describe yeast transcriptional switches with different modes of action and how to alter their properties.

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