Biomedical subjects

Yoshio Suzuki

Publications and source records attributed to Yoshio Suzuki.

At least 19 recordsLinked to original sources

PubMed2007

MPAI (mass probes aided ionization) method for total analysis of biomolecules by mass spectrometry.

We have designed and synthesized various mass probes, which enable us to effectively ionize various molecules to be detected with mass spectrometry. We call the ionization method using mass probes the "MPAI (mass probes aided ionization)" method. We aim at the sensitive detection of various biological molecules, and also the detection of bio-molecules by a single mass spectrometry serially without changing the mechanical settings. Here, we review mass probes for small molecules with various functional groups and mass probes for proteins. Further, we introduce newly developed mass probes for proteins for highly sensitive detection.

Animals↗

PubMed2006

Elemental compositions of comet 81P/Wild 2 samples collected by Stardust.

We measured the elemental compositions of material from 23 particles in aerogel and from residue in seven craters in aluminum foil that was collected during passage of the Stardust spacecraft through the coma of comet 81P/Wild 2. These particles are chemically heterogeneous at the largest size scale analyzed ( approximately 180 ng). The mean elemental composition of this Wild 2 material is consistent with the CI meteorite composition, which is thought to represent the bulk composition of the solar system, for the elements Mg, Si, Mn, Fe, and Ni to 35%, and for Ca and Ti to 60%. The elements Cu, Zn, and Ga appear enriched in this Wild 2 material, which suggests that the CI meteorites may not represent the solar system composition for these moderately volatile minor elements.

Journal Article↗

PubMed2006

Prediction of rebleeding from angiographic features in vertebral artery dissecting aneurysms.

To identify patient characteristics and angiographic features that predict high risk for rebleeding in vertebral artery (VA) dissecting aneurysms. We analyzed 62 patients treated for subarachnoid hemorrhage (SAH) from VA dissecting aneurysms (male: female, 46:16; mean age, 51.7 +/- 8 years). Univariate and multivariate stepwise logistic regression analyses were performed to assess relationships between rebleeding rate and age, gender, history of hypertension, sidedness of the aneurysm, angiographic configuration, and location relative to the origin of the posterior inferior cerebellar artery (PICA). Rebleeding occurred in 22 patients (37%), mostly within 24 h. Patients without rebleeding had favorable outcomes, while patients with rebleeding showed higher mortality. Angiographic patterns with high rebleeding rates included "stenosis and dilation" (50%), and "lateral protrusion" (43%), contrasting with "dilation and stenosis" (20%) and other types. Rebleeding also was likely in aneurysms proximal to or at the PICA origin (rate, 47% or 46%) than distal to the PICA origin (21%). Multivariate logistic regression analysis found two factors independently associated with rebleeding: angiographic pattern of the aneurysm (odds ratio 1.88:1, P=0.0366), and location relative to the PICA origin (odds ratio 4.93:1, P=0.028). High risk of rebleeding in VA dissecting aneurysms can be predicted by angiographic configurations such as "stenosis and dilation" and "lateral protrusion" and by location at or proximal to the PICA origin.

Adult↗

PubMed2006

Protective effect of prostaglandin EP4-receptor agonist on anti-glomerular basement membrane antibody-associated nephritis.

Prostaglandin E(2)-receptor subtypes, EP(1), EP(2), EP(3), and EP(4), are present in the kidney. The aim of this study was to elucidate the anti-nephritic effect of an EP(4)-receptor agonist on an experimental nephritic model. Mice were injected i.v. with anti-glomerulus antiserum to induce nephritis. Nephritic glomeruli generated more prostaglandin E(2) (2.6 and 0.7 ng) and less cyclic AMP than normal glomeruli (11 and 26 pmol). The production of cyclic AMP in nephritic glomeruli increased 67% in response to AE1-329, an EP(4) agonist, at 10(-5) M. Nephritic glomeruli expressed a lesser amount of mRNA of prostaglandin E(2)-receptor subtypes as compared with normal glomeruli. AE1-329 was administered s.c. at 100 microg/kg per day for 3 weeks. AE1-329 suppressed the increase in creatinine and cholesterol compared to those in the control nephritic mice. AE1-329-treated nephritic mice had less crescentic glomeruli and less deposition of rabbit IgG (anti-glomerular basement membrane antibody) in glomeruli than the control mice. AE1-329 prevented the development of glomerulonephritis. These findings suggest that EP(4)-receptor agonists are a promising drug to prevent the development of glomerulonephritis.

Animals↗

PubMed2006

Insufficient expression of cyclooxygenase-2 protein is associated with retarded degradation of aggregated protein in diabetic glomeruli.

To elucidate the involvement of cyclooxygenase (COX) in degradation of aggregated protein in diabetic glomeruli, we used streptozotocin (STZ)-induced diabetic mice and aggregated bovine serum albumin (a-BSA) as a model protein. There was a higher deposition of a-BSA in diabetic glomeruli compared to normal glomeruli 18 h after a-BSA injection at 4 and 8 weeks after STZ. Degradation of a-BSA was confirmed using isolated glomeruli. Diabetic glomeruli produced prostaglandin E(2) (PGE(2)) more than normal glomeruli in the basal level at 8 weeks. a-BSA caused further increase of PGE(2) production in normal glomeruli, but not in diabetic glomeruli. Niflimic acid, a selective COX-2 inhibitor, reduced PGE(2) production of normal glomeruli in the a-BSA loading group, but not that in the control group. In diabetic glomeruli, niflimic acid reduced PGE(2) production in both the control group and a-BSA loading group. In normal glomeruli, a-BSA increased expressions of both COX-2 mRNA and protein. However, in diabetic glomeruli, a-BSA increased COX-2 mRNA expression but not COX-2 protein expression. These results suggest that retarded degradation of aggregated protein in diabetic glomeruli is associated with lack of further expression of COX-2 protein and further production of PGE(2) in response to aggregated protein.

Animals↗

PubMed2006

Stable top-up operation at SPring-8.

Top-up operation allows SPring-8 to provide highly stable X-ray beams with arbitrary filling patterns. The implementation of top-up operation is described, with a focus on the simultaneous achievement of stability of stored current, beam orbit, purity of an isolated single bunch, and beam injection efficiency. Stored-current fluctuations have been routinely reduced to a level of 10(-3). Stored-beam oscillation on frequent beam injection, which was originally regarded as the most serious problem, has been successfully suppressed to a sufficiently low level that it never perturbs imaging experiments. Current impurities in nominally empty buckets have been reduced to a level of 10(-9) over more than one week of operation, making possible the measurement of time-resolved spectra using high-current bunches. Finally, excellent injection efficiency, higher than 80%, is routinely obtained, even for small undulator gaps, which is critical for preventing radiation damage to insertion-device magnets and to reduce leakage radiation. The process of achieving highly stabilized top-up operation at SPring-8 and its utility for user experiments are described.

Electrons↗

PubMed2006

Spontaneous rupture of splenic hamartoma in a patient with hepatitis C virus-related cirrhosis and portal hypertension: a case report and review of the literature.

Spontaneous rupture is a rare complication of splenic hamartoma. A review of the literature revealed only four such cases. To the best of our knowledge, this is the first report of spontaneous rupture of splenic hamartoma associated with liver cirrhosis and portal hypertension. A 53-year-old woman, who was followed up for aortic dissection and hepatitis C virus (HCV)-related liver cirrhosis, was referred with sudden left chest and shoulder pain. An abdominal ultrasound showed intraabdominal bleeding, and computed tomography indicated rupture of a splenic tumor. Emergent splenectomy was carried out. The postoperative course was uneventful, and the patient was discharged on the 13th postoperative day. Pathology revealed the tumor to be a ruptured splenic hamartoma. The non-tumorous splenic parenchyma revealed congestive changes. We consider that the presence of liver cirrhosis and portal hypertension are risk factors for spontaneous rupture of the splenic hamartoma.

Female↗

PubMed2006

Rapid and easy protein staining for SDS-PAGE using an intramolecular charge transfer-based fluorescent reagent.

High-performance staining for 1-D and 2-D SDS-PAGE was carried out using a novel protein-binding fluorophore (Dye 1), which noncovalently interacts with proteins and provides a fluorescence emission response to proteins by intramolecular charge transfer. In order to achieve the high-throughput analysis of proteins for SDS-PAGE, the general protocols for in-gel protein staining (SDS-PAGE, fixation, staining, washing, and detection) were simplified to produce an easy and rapid protocol (SDS-PAGE together with staining, washing, and detection). This method was performed by preparation of an electrophoresis buffer containing Dye 1 under optimum conditions, and by the binding of Dye 1 to proteins in the gel during the SDS-PAGE. As a result, this study required only 15 min for protein staining as a minimum time. On the other hand, it takes several hours for the general protein staining method, such as SYPRO Ruby staining (18 h) and CBB staining (105 min). Moreover, the protein-to-protein variation was low, and the detection limit was 7.0 ng/band of BSA (S/N = 3.0) in this method, which was as sensitive as the short-protocol silver staining methods. On the basis of these results, this rapid and easy protocol for SDS-PAGE using Dye 1 may be widely applicable and convenient for users in the various scientific and medical fields.

Animals↗

PubMed2006

Mass probe-assisted ionization method for total analysis of biomolecules with electrospray ionization-mass spectrometry.

In this paper, we review the mass probes used for the derivation of a variety of biomolecules efficiently detected by the electrospray ionization-mass spectrometry and mass probe-assisted ionization method for total analysis and determination by consecutive detection with a single instrument. We describe mass probes for a variety of molecules including proteins, nucleobases, metallic cations, and other small molecules.

Metals↗

PubMed2005

Design and synthesis of intramolecular charge transfer-based fluorescent reagents for the highly-sensitive detection of proteins.

Novel fluorescent molecular probes possessing both a hydroxystyryl and a cyanopyranyl moieties were designed and synthesized to detect the proteins via noncovalent bonding. These fluorescent probes indicated very weak fluorescence emission in the absence of protein. On the other hand, the fluorescence spectra of these probes showed a large Stokes shift and dramatic increase of fluorescence intensity, and red emission was observed after addition of BSA. These fluorescence spectral changes upon binding proteins were caused by the ICT process. Fluorescence intensities of the probes were plotted as a function of protein concentrations. A good linear relationship was observed up to 1000 microg/mL of protein, and the detection limit was found to be 100 ng/mL at the given assay conditions. Similar results were observed for the measurements of not only BSA but also other proteins (BGG, etc.). The responses of these probes to various nonprotein substances (inorganic salts, chelating agents, etc.) were observed, the fluorescence intensity did not change before and after the addition of foreign substances, and correct protein monitoring was successful using these fluorescent probes. To demonstrate the application of these probes, proteins after the separation using SDS-PAGE were stained in the medium containing 1, and the imaging of the proteins in the gel was successful. The experimental results clearly showed that these probes are good protein indicators for easy and highly sensitive detection.

Drug Design↗

PubMed2005

Increase in the deposition of aggregated protein in the glomeruli of spontaneously diabetic mice.

The aim of this study was to investigate the disposal of aggregated protein in the glomeruli of spontaneously diabetic mice. Diabetic mice, KK-A(y) and db/db, and age-matched ICR mice were injected intravenously with aggregated bovine serum albumin (a-BSA) at 0.6 mg/g, and the glomeruli and the blood were obtained. Diabetic mice had larger amounts of a-BSA in their glomeruli than the ICR mice, threefold in KK-A(y) and twofold in db/db, at 3 h after the a-BSA injection. Additionally, the disappearance of a-BSA was retarded in the diabetic glomeruli. KK-A(y) displayed a-BSA in the glomeruli 24 h after the a-BSA injection and db/db did after 12 h, while the ICR did by 8 h. In spite of increases of insulin to similar degrees in both strains of diabetic mice after the a-BSA injection, blood glucose levels markedly decreased in KK-A(y) compared with db/db. There were no histopathological alterations in the glomeruli of the diabetic mice. Depositions of a-BSA were confirmed to be higher in the diabetic glomeruli by the immunofluorescence technique, and KK-A(y) displayed higher depositions of a-BSA than did db/db. The present study suggests that hyperglycemia is involved in the increased deposition of aggregated protein in the glomeruli and that the degradation of aggregated protein is retarded in diabetic glomeruli.

Animals↗

PubMed2005

Cerebrospinal fluid taurine after traumatic brain injury.

In the experimental setting, taurine is known to be released from swollen cells to reestablish their normal volume. However, its clinical relevance has not been fully understood. This study was undertaken to reveal changes in cerebrospinal fluid (CSF) amino acids concentration in patients with severe traumatic brain injury (TBI). The study included eight patients, in whom a ventricular catheter was inserted to measure intracranial pressure and obtain CSF samples for 5 days. CSF obtained from patients with normal pressure hydrocephalus served as a control. CSF taurine concentration increased 1.8 times control (P < 0.05) after TBI and returned to control value approximately 67 h after injury. Taurine decreased further and remained lower than control thereafter. Phosphoethanolamine showed similar increase, whereas glutamine decreased transiently and arginine remained close to control value. The present data support the period of astrocytic swelling observed after TBI in other morphological studies. The mechanism and consequences of CSF taurine decrease in the subacute stage of TBI need to be elucidated.

Adolescent↗

PubMed2005

Effect of wheat gluten hydrolysate on the immune system in healthy human subjects.

Nine healthy volunteers were divided into a test group (n = 5) and a control group (n = 4). The test group consumed 3 grams per d of wheat gluten hydrolysate for 6 d, and their NK cell activity and hematological parameters were measured: The same assessments were performed in the control group, which did not receive wheat gluten hydrolysate. In the test group, NK cell activity increased significantly (P = 0.018) after wheat gluten hydrolysate intake. No adverse effects were observed in either group.

Adjuvants, Immunologic↗

PubMed2005

Fetal growth restriction associated with measles virus infection during pregnancy.

We report on a 28-week infant with growth restriction starting after 23 weeks' gestation because of measles virus (MV) infection of the mother. Histological findings for the placenta revealed extensive fibrin deposition and necrosis of the villi, and MV antigen was demonstrated in the syncytiotrophoblast by immunostaining. The MV-specific IgM level in the infant was negative, but that of the mother was positive. Therefore, we speculate that growth restriction is not attributed to direct infection with MV, but to placental dysfunction due to a decrease in intravillous blood flow and oxygen supply to the fetus.

Adult↗

PubMed2005

Mutagenicity of coenzyme Q10.

Mutagenicity of organically synthesized coenzyme Q10 (CoQ10) was determined by Ames assay in the presence and absence of S9 mix. The tester strains were Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and Escherichia coli WP2 uvr A. CoQ10 displayed no mutagenicity in any tester strain at any dose tested. Therefore, organically synthesized CoQ10 was considered to possess no mutagenicity.

Coenzymes↗

PubMed2005

[An autopsied case of paraneoplastic neurologic syndrome (limbic encephalitis, cerebellar degeneration, and pseudohypertrophy in the inferior olivary nuclei) associated with T cell lymphoma].

We describe a patient with paraneoplastic neurologic syndrome confirmed on postmortem examination. This 42-year-old man was admitted due to general fatigue, emaciation and acute-onset disorientation. Neurological examination revealed disorientation, moderate cognitive impairment, cerebellar ataxia, bilateral limitations and nystagmus in all directions during external ocular movement, swallowing disorder, bilateral Babinski sign, sensory disturbance in the distal parts of all extremities, and Romberg's sign. T-cell lymphoma was diagnosed following biopsy of the cervical lymph node. Neurological condition improved slightly after chemotherapy, but subsequently deteriorated. At about 6 years after the disease onset, brain magnetic resonance imaging (MRI) revealed atrophy of bilateral hippocampi and the upper vermis of the cerebellum. The patient died of pneumonia after a clinical course of about 6 years and 6 months. Pathologically, neuronal loss, reactive gliosis and perivascular lymphocytic infiltration were observed in the hippocampi, cerebellum, and inferior olivary nuclei. Lymphocytes around the vessels were positive for LCA and UCHL-1, but negative for CD8 and L26, and thus were considered to be T cells. No lymphoma cell was observed in the central nervous system or lymphatic organs. Based on the pathological findings, paraneoplastic neurologic syndrome (limbic encephalitis, cerebellar degeneration and olivary pseudohypertrophy) associated with T-cell type malignant lymphoma was diagnosed. Only three other cases of paraneoplastic neurologic syndrome associated with T-cell lymphoma have been reported. In those cases, death occurred due to the deterioration of malignant lymphoma, whereas the present patient died about 6 years after the remission of malignant lymphoma. Prognosis may thus depend on the course of the malignant lymphoma. In the present patient, neurological symptoms deteriorated after remission of malignant lymphoma, and no pathological lesion were found in the lymphatic organs. Lesions in the central nervous system in paraneoplastic neurological syndromes may follow a course independent of the original malignant disease.

Humans↗

PubMed2004

Design and synthesis of highly sensitive and selective fluorescein-derived magnesium fluorescent probes and application to intracellular 3D Mg2+ imaging.

The role of intracellular magnesium ions is of high interest in the fields of pharmacology and cellular biology. To accomplish the dynamic and three-dimensional imaging of intracellular Mg2+, there is a strong desire for the development of optimized Mg2+ fluorescent probes. In this paper we describe the design, synthesis, and cellular application of the three novel Mg2+ fluorescent probes KMG-101, -103, and -104. The compounds of this series feature a charged beta-diketone as a binding site specific for Mg2+ and a fluorescein residue as the fluorophore that can be excited with an Ar+ laser such as is widely used in confocal scanning microscopy. This molecular design leads to an intensive off-on-type fluorescent response toward Mg2+ ions. The two fluorescent probes KMG-103 and -104 showed suitable dissociation constants (Kd,Mg2+ = 2 mM) and nearly a 10-fold fluorescence enhancement over the intracellular magnesium ion concentration range (0.1-6 mM), allowing high-contrast, sensitive, and selective Mg2+ measurements. For intracellular applications, the membrane-permeable probe KMG-104AM was synthesized and successfully incorporated into PC12 cells. Upon application of the mitochondria uncoupler FCCP to the probe-incorporated cells, the resulting increase in the free magnesium ion concentration could be followed over time. By using a confocal microscope, the intracellular 3D magnesium ion concentration distributions were satisfactorily observed.

Animals↗

PubMed2004

Regulation of expression of the stress response gene, Osp94: identification of the tonicity response element and intracellular signalling pathways.

Osp94 (osmotic stress protein of 94 kDa) is known to be up-regulated by hypertonic and heat-shock stresses in mouse renal inner medullary collecting duct (mIMCD3) cells. To investigate the molecular mechanism of transcriptional regulation of the Osp94 gene under these stresses, we cloned and characterized the 5'-flanking region of the gene. Sequence analysis of the proximal 4 kb 5'-flanking region revealed a TATA-less G/C-rich promoter region containing a cluster of Sp1 sites. We also identified upstream sequence motifs similar to the consensus TonE/ORE (tonicity-response element/osmotic response element) as well as the consensus HSE (heat-shock element). Luciferase activities in cells transfected with reporter constructs containing a TonE/ORE-like element (Osp94-TonE; 5'-TGGAAAGGACCAG-3') and HSE enhanced reporter gene expression under hypertonic stress and heat-shock stress respectively. Electrophoretic gel mobility-shift assay showed a slowly migrating band binding to the Osp94-TonE probe, probably representing binding of TonEBP (TonE binding protein) to this enhancer element. Furthermore, treatment of mIMCD3 cells with MAPK (mitogen-activated protein kinase) inhibitors (SB203580, PD98059, U0126 and SP600125) and a proteasome inhibitor (MG132) suppressed the increase in Osp94 gene expression caused by hypertonic NaCl. These results indicate that the 5'-flanking region of Osp94 gene contains a hypertonicity sensitive cis -acting element, Osp94-TonE, which is distinct from a functional HSE. Furthermore, the MAPK and proteasome systems appear to be, at least in part, involved in hypertonic-stressmediated regulation of Osp94 through Osp94-TonE.

5' Flanking Region↗