Publications by authors named "Yoshinori Tsuji"

Pyrenoids are subcompartments of algal chloroplasts that increase the efficiency of Rubisco-driven CO fixation. Diatoms fix up to 20% of global CO, but their pyrenoids remain poorly characterized. Here, we used in vivo photo-crosslinking to identify pyrenoid shell (PyShell) proteins, which we localized to the pyrenoid periphery of model pennate and centric diatoms, Phaeodactylum tricornutum and Thalassiosira pseudonana.

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Carbonic anhydrase (CA), an enzyme conserved across species, is pivotal in the interconversion of inorganic carbon (Ci; CO2, and HCO3-). Compared to the well-studied intracellular CA, the specific role of extracellular CA in photosynthetic organisms is still not well understood. In the green alga Chlamydomonas (Chlamydomonas reinhardtii), carbonic anhydrase 1 (CAH1), located at the periplasmic space, is strongly induced under CO2-limiting conditions by the Myb transcription factor LCR1.

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Anion transporters sustain a variety of physiological states in cells. Bestrophins (BSTs) belong to a Cl- and/or HCO3- transporter family conserved in bacteria, animals, algae, and plants. Recently, putative BSTs were found in the green alga Chlamydomonas reinhardtii, where they are upregulated under low CO2 (LC) conditions and play an essential role in the CO2-concentrating mechanism (CCM).

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Using numerical indices and visual evaluation, we evaluated the dependence of coronary-artery depictability on the denoising parameter in compressed sensing magnetic resonance angiography (CS-MRA). This study was conducted to clarify the acceleration factor (AF) and denoising factor (DF) dependence of CS-MRA image quality. Vascular phantoms and clinical images were acquired using three-dimensional CS-MRA on a clinical 1.

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Marine diatoms express genes encoding potential phosphate transporter and alkaline phosphatase (APase) under phosphate-limited (-P) condition. This indicates that diatoms use high-affinity phosphate uptake system with organic phosphate hydration. The function of molecules playing roles for Pi uptake was determined in this study.

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Carbonic anhydrase (CA) is a crucial component for the operation of CO-concentrating mechanisms (CCMs) in the majority of aquatic photoautotrophs that maintain the global primary production. In the genome of the centric marine diatom, Thalassiosira pseudonana, there are four putative gene sequences that encode θ-type CA, which was a type of CA recently identified in marine diatoms and green algae. In the present study, specific subcellular locations of four θCAs, TpθCA1, TpθCA2, TpθCA3, and TpθCA4 were determined by expressing GFP-fused proteins of these TpθCAs in T.

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Proteins immobilized on biosilica which have superior reactivity and specificity and are innocuous to natural environments could be useful biological materials in industrial processes. One recently developed technique, living diatom silica immobilization (LiDSI), has made it possible to immobilize proteins, including multimeric and redox enzymes, via a cellular excretion system onto the silica frustule of the marine diatom . However, the number of application examples so far is limited, and the type of proteins appropriate for the technique is still enigmatic.

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Plants produce a large variety of lipophilic metabolites, many of which are secreted by cells and accumulated in apoplasts. These compounds often play a role to protect plants from environmental stresses. However, little is known about how these lipophilic compounds are secreted into apoplastic spaces.

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The availability of CO2 is one of the restrictions on aquatic photosynthesis. Solute carrier (SLC) 4-2, a plasma membrane HCO3- transporter has previously been identified in the marine diatom Phaeodactylum tricornutum. In this study, we discovered two paralogs, PtSLC4-1 and PtSLC4-4, that are both localized at the plasma membrane.

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Yet another kinase (YAK) 1 is a conserved eukaryotic protein kinase coordinating growth and development. We previously isolated a mutant of Chlamydomonas reinhardtii defective in the YAK1 ortholog triacylglycerol (TAG) accumulation regulator 1 (TAR1). The mutant tar1-1 displayed higher levels of chlorophyll, starch, TAG, and biomass than the parental strain C9 (renamed as C9-3) in photoautotrophic nitrogen (N)-deficient conditions.

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Intrinsic anti-tachycardia pacing (iATP) is a novel automated ATP algorithm that employs post-pacing interval (PPI) to design the next ATP sequence based on an analysis of the prior failed ATP sequence. A patient with hypertrophic cardiomyopathy received an implantable cardioverter-defibrillator (ICD) (Cobalt™ XT DR, Medtronic, Minneapolis, MN, USA) following an episode of syncope due to macro-reentrant ventricular tachycardia (VT) (right bundle branch block configuration, cycle length [CL] 280 ms). The VF zone was set to VTCL <300 ms and iATP therapy was prescribed before and during capacitor charging.

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Microalgae induce a CO-concentrating mechanism (CCM) to overcome CO-limiting stress in aquatic environments by coordinating inorganic carbon (Ci) transporters and carbonic anhydrases (CAs). Two mechanisms have been suggested to facilitate Ci uptake from aqueous media: Na-dependent HCO uptake by solute carrier (SLC) family transporters and accelerated dehydration of HCO to CO by external CA in model diatoms. However, studies on ecologically and industrially important diatoms including Chaetoceros gracilis, a common food source in aquacultures, are still limited.

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Of all the eukaryotic algal groups, diatoms make the most substantial contributions to photosynthesis in the contemporary ocean. Understanding the biological innovations that have occurred in the diatom chloroplast may provide us with explanations to the ecological success of this lineage and clues as to how best to exploit the biology of these organisms for biotechnology. In this paper, we use multi-species transcriptome datasets to compare chloroplast metabolism pathways in diatoms to other algal lineages.

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Photoacclimation consists of short- and long-term strategies used by photosynthetic organisms to adapt to dynamic light environments. Observable photophysiology changes resulting from these strategies have been used in coarse-grained models to predict light-dependent growth and photosynthetic rates. However, the contribution of the broader metabolic network, relevant to species-specific strategies and fitness, is not accounted for in these simple models.

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Aim: The Cardio-Ankle Vascular Index (CAVI) is a stiffness index of the arterial tree from the origin of the aorta to the ankle, independent of blood pressure at the time of measurement. The CAVI equation includes the coefficients "a" and "b" to adjust it to the value of Hasegawa's pulse wave velocity, which is compensated for at 80 mmHg of diastolic pressure. To verify this adjustment with the coefficients, the clinical significance of CAVI and CAVI without the coefficients (haβ) were compared in both an epidemiological study and an acute clinical study.

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The controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) technique can decrease scan time. The purpose of this study was to determine whether an arterial phase scan can be performed in 5 s using the CAIPIRINHA short-scan and a reference scanning technique. The generalized autocalibrating partially parallel acquisition (GRAPPA), the CAIPIRINHA routine (CAIPI-routine), and the CAIPIRINHA short-scanning (CAIPI-short) methods were compared.

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Diatoms are one of the most successful marine eukaryotic algal groups, responsible for up to 20% of the annual global CO fixation. The evolution of a CO-concentrating mechanism (CCM) allowed diatoms to overcome a number of serious constraints on photosynthesis in the marine environment, particularly low [CO] in seawater relative to concentrations required by the CO fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO), which is partly due to the slow diffusion rate of CO in water and a limited CO formation rate from [Formula: see text] in seawater. Diatoms use two alternative strategies to take up dissolved inorganic carbon (DIC) from the environment: one primarily relies on the direct uptake of [Formula: see text] through plasma-membrane type solute carrier (SLC) 4 family [Formula: see text] transporters and the other is more reliant on passive diffusion of CO formed by an external carbonic anhydrase (CA).

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Background/aims: Noninvasive liver fibrosis evaluation was performed in patients with nonalcoholic fatty liver disease (NAFLD). We used a quantitative method based on the hepatic volume acquired from gadoxetate disodium-enhanced (Gd-EOB-DTPA-enhanced) magnetic resonance imaging (MRI) for diagnosing advanced fibrosis in patients with NAFLD.

Methods: A total of 130 patients who were diagnosed with NAFLD and underwent Gd-EOB-DTPA-enhanced MRI were retrospectively included.

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Diatoms operate a CO2-concentrating mechanism (CCM) that drives upwards of 20% of annual global primary production. Recent progress in CCM research in the marine pennate diatom Phaeodactylum tricornutum revealed that this diatom directly takes up HCO3- from seawater through low-CO2-inducible plasma membrane HCO3- transporters, which belong to the solute carrier (SLC) 4 family. Apart from this, studies of carbonic anhydrases (CAs) in diatoms have revealed considerable diversity in classes and localization among species.

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The acquisition of dissolved inorganic carbon (DIC) in CO2-limited seawater is a central issue to understand in marine primary production. We previously demonstrated the occurrence of direct HCO3- uptake by solute carrier (SLC) 4 transporters in a diatom, a major marine primary producer. Homologs of SLC are found in both centric and pennate marine diatoms, suggesting that SLC transporters are generally conserved.

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The algal pyrenoid is a large plastid body, where the majority of the CO2-fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) resides, and it is proposed to be the hub of the algal CO2-concentrating mechanism (CCM) and CO2 fixation. The thylakoid membrane is often in close proximity to or penetrates the pyrenoid itself, implying there is a functional cooperation between the pyrenoid and thylakoid. Here, GFP tagging and immunolocalization analyses revealed that a previously unidentified protein, Pt43233, is targeted to the lumen of the pyrenoid-penetrating thylakoid in the marine diatom Phaeodactylum tricornutum The recombinant Pt43233 produced in Escherichia coli cells had both carbonic anhydrase (CA) and esterase activities.

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Aim: The two-point Dixon method for magnetic resonance imaging (MRI) is commonly used to non-invasively measure fat deposition in the liver. The aim of the present study was to assess the usefulness of MRI-fat fraction (MRI-FF) using the two-point Dixon method based on the non-alcoholic fatty liver disease activity score.

Methods: This retrospective study included 106 patients who underwent liver MRI and MR spectroscopy, and 201 patients who underwent liver MRI and histological assessment.

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The bloom-forming coccolithophore Emiliania huxleyi (Haptophyta) is a dominant marine phytoplankton, cells of which are covered with calcareous plates (coccoliths). E. huxleyi produces unique lipids of C37-C40 long-chain ketones (alkenones) with two to four trans-unsaturated bonds, β-glucan (but not α-glucan) and acid polysaccharide (AP) associated with the morphogenesis of CaCO3 crystals in coccoliths.

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Purpose: To investigate whether gadoxetate disodium affects peripheral capillary oxygen saturation (SpO2) and/or heart rate (HR) during dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging in patients with liver diseases.

Materials And Methods: This retrospective study was approved by the institutional review board, who waived the requirement for informed consent. Four hundred fifty-eight patients (171 women [mean age, 66.

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