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Biomedical subjects

M Ogawa

Publications and source records attributed to M Ogawa.

At least 37 records · Page 2Linked to original sources
PubMed2004

A new diagnostic test for VLCAD deficiency using immunohistochemistry.

BACKGROUND: Muscle pathology is often unhelpful in elucidating the specific underlying abnormality in patients with metabolic myopathy with rhabdomyolysis, including very-long chain acyl-CoA dehydrogenase (VLCAD) deficiency. Biochemical analyses require large amounts of biopsy samples for each enzyme assay. OBJECTIVE: To develop a more efficient diagnostic method for VLCAD deficiency. METHODS: The authors performed immunohistochemical analysis using an antibody to VLCAD on muscles from 344 patients (226 men and 118 women) without a specific diagnosis who had at least one of the following symptoms: myoglobinuria, high CK level, muscle pain, muscle stiffness, sudden infant death syndrome, and Reye-like syndrome. RESULTS: Immunoreactivity to VLCAD was absent or markedly reduced in 13 patients. Biochemical analyses confirmed that all these patients had low enzymatic activity and reduced amount of protein. They all had the myopathic phenotype. The authors identified homozygous or compound heterozygous mutations in all of them. All recombinant proteins had reduced enzymatic activity except for 128G>A (G43D) and 796C>G (P266A) mutants, indicating that they are neutral polymorphisms. CONCLUSIONS: The new screening method for the detection of VLCAD deficiency using an immunohistochemical technique identified 13 new Japanese patients with VLCAD deficiency.

Acyl-CoA Dehydrogenase, Long-Chain↗
PubMed2004

POMT1 mutation results in defective glycosylation and loss of laminin-binding activity in alpha-DG.

Walker-Warburg syndrome (WWS) is a congenital muscular dystrophy associated with neuronal migration disorder and structural eye abnormalities. The mutations in the O-mannosyltransferase 1 gene (POMT1) were identified recently in 20% of patients with WWS. The authors report on a patient with WWS and a novel POMT1 mutation. Their patient expressed alpha-dystroglycan (alpha-DG) core protein, but fully glycosylated alpha-DG antibody epitopes were absent, associated with the loss of laminin-binding activity.

Abnormalities, Multiple↗
PubMed2004

Is the degree of fetal hepatosplenomegaly with transient abnormal myelopoiesis closely related to the postnatal severity of hematological abnormalities in Down syndrome?

We present three cases of transient abnormal myelopoiesis associated with trisomy 21 in which hepatomegaly was apparent during the fetal period. In the first case, the fetal hepatosplenomegaly was severe, multiple organ failure occurred in the neonatal period and death ensued at 4 weeks of age. In the second case, the hepatomegaly was moderate, and with conservative treatment in the neonatal period the outcome was good. In the third case, hepatomegaly was mild and improved spontaneously, and the hematological abnormalities required only conservative treatment in the neonatal period. Our experience raises the question of whether fetal hepatosplenomegaly is a predictor of transient myeloproliferative disorder with trisomy 21 and whether the degree of fetal hepatomegaly is a marker for the neonatal severity of hematological abnormalities.

Adult↗
PubMed2004

Targeted conversion of the transthyretin gene in vitro and in vivo.

Familial amyloidotic polyneuropathy (FAP) is the common form of hereditary generalized amyloidosis and is characterized by the accumulation of amyloid fibrils in the peripheral nerves and other organs. Liver transplantation has been utilized as a therapy for FAP, because the variant transthyretin (TTR) is predominantly synthesized by the liver, but this therapy is associated with several problems. Thus, we need to develop a new treatment that prevents the production of the variant TTR in the liver. In this study, we used HepG2 cells to show in vitro conversion of the TTR gene by single-stranded oligonucleotides (SSOs), embedded in atelocollagen, designed to promote endogenous repair of genomic DNA. For the in vivo portion of the study, we used liver from transgenic mice whose intrinsic wild-type TTR gene was replaced by the murine TTR Val30Met gene. The level of gene conversion was determined by real-time RCR combined with mutant-allele-specific amplification. Our results indicated that the level of gene conversion was approximately 11 and 9% of the total TTR gene in HepG2 cells and liver from transgenic mice, respectively. Gene therapy via this method may therefore be a promising alternative to liver transplantation for treatment of FAP.

Amyloid Neuropathies↗
PubMed2004

Inactivation of Chlamydia trachomatis and Chlamydia (Chlamydophila) pneumoniae by ozone.

AIMS: To clarify the inhibitory effects of ozone on Chlamydia trachomatis and C. pneumoniae. METHODS AND RESULTS: Cell culture was performed using HeLa229 cells for C. trachomatis, and Human Line cells for C. pneumoniae. C. trachomatis strain D/UW-3/Cx and C. pneumoniae strain AR-39 were used. Ozone water was generated by an ozone water dispenser and diluted to desired concentration just before each experiment. Preinoculation minimum cidal concentration (MCC) and postinoculation MCC methods were employed. In preinoculation MCC, chlamydial strains were treated with serially diluted ozone water followed by inoculation to cells. In postinoculation method, chlamydial strains were inoculated to cells and incubated for 24 h. Then infected cells were treated with ozone water, followed by additional incubation for 48 h. Complete inactivation was obtained in preinoculation MCC method at 0.5 ppm of ozone water for 30 s, or 4 ppm for 5 s. CONCLUSION: Ozone at a concentration of 4 ppm was enough for immediate inactivation of both C. trachomatis and C. pneumoniae. SIGNIFICANCE AND IMPACT OF THE STUDY: Ozone water at 4 ppm should be applicable for prevention of C. trachomatis urogenital infections.

Cell Line↗
PubMed2004

Anti-Hu associated paraneoplastic sensory neuronopathy with upper motor neurone involvement.

Paraneoplastic neurological syndrome is characterised by neuronal degeneration with lymphocytic infiltration in various regions of the central and peripheral nervous systems. Motor neurone symptoms may occur as a remote effect of malignancy, and have been considered because of the involvement of lower motor neurones. A case is reported of an 80 year old woman suffering from paraneoplastic sensory neuronopathy with anti-Hu antibody. Postmortem examination showed adenocarcinoma of the gall bladder and small cell carcinoma of the duodenum. Neuronal loss with lymphocytic infiltration was found in the dorsal root ganglia, brain stem, and cerebellum. Despite the absence of upper motor neurone signs, there was severe loss of Betz cells and degeneration of the bilateral pyramidal tracts. To our knowledge, this is the first demonstration of upper motor neurone involvement in anti-Hu associated paraneoplatic syndrome.

Adenocarcinoma↗
PubMed2003

Preoperative administration of rebamipide significantly lowers body temperature and circulating interleukin-6 in gastric cancer patients after gastrectomy.

BACKGROUND/AIMS: It has recently been reported that rebamipide (OPC-12759) inhibits inflammatory cytokines and activation of neutrophils. The aim of the present study was to investigate the effects of preoperative administration of rebamipide on parameters of systemic inflammatory response syndrome (SIRS) and serum levels of inflammatory cytokines in gastric cancer patients after gastrectomy. PATIENTS AND METHODS: We measured the parameters of SIRS, circulating cytokines and acute phase reactants in patients after (i). distal gastrectomy with D2 lymph node dissection (group 1, n = 10); (ii). distal gastrectomy with D2 lymph node dissection following administration of rebamipide (group 2, n = 10), and (iii). laparoscopy-assisted distal gastrectomy (LADG) with D1 lymph node dissection (group 3, n = 10). Group 2 was administered 100 mg of rebamipide 3 times/day after meals for 7 days before surgery. RESULTS: Among the parameters of SIRS, a difference was observed in body temperature on day 3. The mean body temperature of group 2 was significantly lower than group 1 (p = 0.006), and was similar to group 3. In proinflammatory cytokines, a significant difference was observed in the serum levels of interleukin (IL)-6. On day 1 the IL-6 levels of group 2 were significantly lower than those of group 1 (p < 0.001). The changes in the IL-6 level of group 2 were similar to group 3, except in the very early postoperative phase. However, other proinflammatory cytokines, such as IL-8 and IL-10, were not detected, and there was no difference in C-reactive protein between the 3 groups. CONCLUSION: Preoperative administration of rebamipide significantly decreased postoperative body temperatures and circulating IL-6 in gastric cancer patients after gastrectomy to levels similar to those of patients with LADG.

Aged↗
PubMed2003

Neurons but not glial cells show reciprocal imprinting of sense and antisense transcripts of Ube3a.

The human UBE3A gene shows brain-specific partial imprinting, and lack of a maternally inherited allele causes Angelman syndrome (AS), which is characterized by neurobehavioral anomalies. In several AS model mice, imprinted Ube3a expression is detected predominantly in the hippocampus, cerebellar Purkinje cells and the olfactory bulb. Therefore, imprinting of mouse Ube3a is thought to be region-specific with different levels of silencing of the paternal Ube3a allele in different brain regions. To determine cell types of imprinted Ube3a expression, we analyzed its imprinting status in embryonic brain cells by using primary cortical cell cultures. RT-PCR and immunofluorescence were performed to determine the allelic expression of the gene. The Ube3a gene encodes two RNA transcripts in the brain, sense and antisense. The sense transcript was expressed maternally in neurons but biallelically in glial cells in the embryonic brain, whereas the antisense transcript was expressed only in neurons and only from the paternal allele. Our data present evidence of brain cell type-specific imprinting, i.e. neuron-specific imprinting of Ube3a in primary brain cell cultures. Reciprocal imprinting of sense and antisense transcripts present only in neurons suggests that the neuron-specific imprinting mechanism is related to the lineage determination of neural stem cells.

Angelman Syndrome↗
PubMed2003

Antiapoptotic effect of haem oxygenase-1 induced by nitric oxide in experimental solid tumour.

Induction of haem oxygenase-1 (HO-1) may provide an important protective effect for cells against oxidative stress. Here, we investigated the mechanism of cytoprotection of HO-1 in solid tumour with a focus on the antiapoptotic activity of HO-1. Treatment of rat hepatoma AH136B cells with the HO inhibitor zinc protoporphyrin IX (ZnPP IX) or tin protoporphyrin IX resulted in extensive apoptotic changes of tumour cells both in vivo and in vitro. Caspase-3 activity of the ZnPP IX-treated hepatoma cells increased significantly. Moreover, ZnPP IX-induced apoptosis was completely inhibited by simultaneous incubation with a specific caspase-3 inhibitor and was partially abrogated by bilirubin, a reaction product of HO. In vivo ZnPP IX treatment did not affect nitric oxide (NO) production and tumour blood flow. Western blot analyses showed that HO-1 expression in AH136B cells was strongly upregulated by NO donors, for example, S-nitroso-N-acetyl penicillamine and propylamine NONOate in vitro; conversely, it was remarkably reduced in vivo by pharmacological blockade of NOS. We conclude that HO-1 may function in antiapoptotic defense of the tumour, and thus it may have important protective and beneficial effects for tumour cells against oxidative stress induced by NO, which is produced in excess during solid tumour growth in vivo.

Animals↗
PubMed2003

Biochemical and molecular characterization of a rice glutelin allele for the GluA-1 gene.

The rice ( Oryza sativa L.) mutant of glu4a, lacking the glutelin alpha-2 subunit while the alpha-1 subunit increased (alpha-1H/alpha-2L), was used in this study. Two-dimensional electrophoresis analysis revealed that the mutant lacked the polypeptide pI6.71/alpha-2 encoded by glu4 while forming a new polypeptide of pI6.50/alpha-1. Experiments were conducted to identify the relationships between the mutated polypeptides of the mutant and to illustrate the mutation mechanism of the allele. Peptide mapping and amino-acid sequence analyses revealed that the newly formed glu4a encoded polypeptide pI6.50/alpha-1 of high homology with the deleted pI6.71/alpha-2 polypeptide which was encoded by glu4 (GluA-1). The nucleotide sequence revealed that the iso-electric point variation of the pI6.50/alpha-1 polypeptide was caused by a point mutation with nucleotide replacement at the variable region of the gene. These results suggested the possibility of altering glutelin quality by using single gene mutation.

Alleles↗
PubMed2003

Regioselective hydroxylation of quinolinic acid, lutidinic acid and isocinchomeronic acid by resting cells of pyridine dicarboxylic acid-degrading microorganisms.

Microorganisms aerobically degrading quinolinic acid, lutidinic acid or isocinchomeronic acid were isolated and the microbial regioselective hydroxylation of these pyridine dicarboxylic acids was studied. Alcaligenes sp. UK21 cells converted quinolinic acid into 6-hydroxypicolinic acid, suggesting the involvement of two enzyme reactions catalyzing hydroxylation at position C6 and decarboxylation at position C3 of quinolinic acid. Resting cells of Alcaligenes sp. UK21 accumulated 94.9 mM 6-hydroxypicolinic acid (13.2 g l(-1)), with a 96% molar conversion yield by 48 h incubation. Rhizobium sp. LA17 and Hydrogenophaga sp. IMA01 catalyzed the regioselective hydroxylation of lutidinic acid and isocinchomeronic acid into 6-hydroxylutidinic acid and 6-hydroxyisocinchomeronic acid, respectively. 6-Hydroxylutidinic acid accumulated up to 95.4 mM (17.5 g l(-1)) by 24 h incubation in the resting cells reaction, using Rhizobium sp. LA17, with a 99% molar conversion yield. Resting cells of Hydrogenophaga sp. IMA01 produced 88.7 mM 6-hydroxyisocinchomeronic acid (16.2 g l(-1)) by 24 h incubation, with a 81% molar conversion yield.

Alcaligenes↗
PubMed2003

Effects of monoamine oxidase inhibitors on the diethyldithiocarbamate-induced enhancement of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxicity in C57BL/6 mice.

Diethyldithiocarbamate (DDC) is known to potentiate the neurotoxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The aims of the present study were to provide biochemical, pathological and behavioral evidence for the degeneration of dopamine (DA) neurons in C57BL/6 strain mice treated simultaneously with DDC and MPTP, and to evaluate the effects of monoamine oxidase (MAO) inhibitors on DDC-enhanced MPTP toxicity. DDC (400 mg/kg)+ MPTP (30 mg/kg) treatment decreased significantly the levels of striatal DA and its metabolites and induced bradykinesia. In mice treated with DDC+MPTP, degenerative areas were found in striatum, substantia nigra and tuberculum olfactorium by assessment of the binding of [125I]RTI-121, a DA transporter ligand. Pretreatment with a MAO-B inhibitor selegiline prior to the administration of DDC and MPTP completely inhibited the decrease in the levels of DA and its metabolites, bradykinesia and degeneration of dopaminergic nerve terminals. In contrast, the protective action of clorgyline was not clearly observed in this model system.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2003

CD38 expression by hematopoietic stem cells of newborn and juvenile mice.

While investigators in a number of laboratories have documented that the hematopoietic stem cells (HSCs) of fetal and adult mice are CD38+, no information is available about CD38 expression by HSCs of newborn and juvenile mice. We used a murine transplantation model to examine HSC CD38 expression. First, we observed that all HSCs from newborn bone marrow are CD38-. Next, it was determined that the majority of HSCs in the bone marrow of 5-week-old mice are CD38-, with a minority being CD38+. These observations indicated that the CD38+ subpopulation of HSC appears before the age of 5 weeks and expands during adolescence. However, the majority of HSCs of 5-week-old mice became CD38+ following injection of 5-fluorouracil, indicating that activation of juvenile stem cells enhances CD38 expression. These observations may have implications for CD38 expression by HSCs from human umbilical cord blood and bone marrow of young children in steady state and under pathological conditions.

ADP-ribosyl Cyclase↗
PubMed2003

Human cord blood long-term engrafting cells are CD34+ CD38-.

There have been controversies about CD34 and CD38 expression by human cord blood (CB) stem cells. Using the newborn NOD/SCID/beta2-microglobulin-null mouse assay that we recently developed, we examined the in vivo engrafting capability of human CB cells. Almost all of the 4-5 months engrafting cells were found in CD34(+) population. The capability of secondary reconstitution was found only in the CD34(+) cells. When the CD34(+) CB cells were separated into CD38(-) and CD38(+) subpopulations and tested for engraftment, the majority of the engrafting cells were detected in the CD38(-) subpopulation. These findings are consistent with the results from studies of murine stem cells and strongly indicate that the phenotype of human CB stem cells is CD34(+) CD38(-).

ADP-ribosyl Cyclase↗
PubMed2003

Development of multicolour digital image analysis system to enumerate actively respiring bacteria in natural river water.

AIMS: To develop a rapid and simple method for the assessment of metabolic activity of bacteria in natural environment. METHODS AND RESULTS: A rapid and simple multicolour digital image analysis system for enumerating viable bacteria based on active fluorescent staining has been developed. This system can accurately differentiate actively respiring bacteria and non-respiring bacteria by distinctive colour information in the digital image captured by an epifluorescence microscope equipped with low magnification objective lens. An algorithm to distinguish bacteria from considerable detritus, which produced bright fluorescence in different colours, by colour segmentation has also been developed. This system was applied to river water samples, and the total and respiratory active bacterial counts by digital image analysis were highly related to those by epifluorescence microscopy (r2 = 0.96 and 0.93, respectively). CONCLUSION: This system allowed the rapid and simple differentiation of bacteria from detritus and concurrent assessment of their metabolic activity, with results being available within 1 h. SIGNIFICANCE AND IMPACT OF THE STUDY: The low magnification image analysis allows more rapid and simple quantification of bacteria and could considerably decrease image data amount and acquisition time. This system could be easily applied to the rapid analysis of microbes in various environments.

Algorithms↗