Search PubMed⌕ Search

Biomedical subjects

M Matsuo

Publications and source records attributed to M Matsuo.

At least 145 records · Page 8Linked to original sources
PubMed1999

Neonatal hyperbilirubinemia associated with Southeast Asian ovalocytosis.

We report, herein, an infant who is twin A of a dizygotic twin, with premature birth and both twins having hemoglobin (Hb) E heterozygosity. Twin A who had Southeast Asian ovalocytosis (SAO) developed neonatal jaundice at the age of 2 days and needed phototherapy at the age of 3 days. The microbilirubin level was rapidly rising up to 535.2 micromol/L (31.3 mg/dl) with the hematocrit value of 38% at the age of 4 days prior to exchange blood transfusion. Exchange blood transfusion was done by 220 ml of O, Rh positive packed red blood cell reconstituted with 180 ml of O, Rh positive fresh plasma to lower the bilirubin level. Twin A received phototherapy from about 8 hr prior to exchange blood transfusion until 3 days later. Twin B, who did not have SAO, developed neonatal hyperbilirubinemia and needed only phototherapy. Twin A received a deletion of 27 basepairs in the erythroid band 3 gene and Hb E heterozygosity from his father.

Anion Exchange Protein 1, Erythrocyte↗
PubMed1999

High incidence of a survival motor neuron gene/cBCD541 gene ratio of 2 in Japanese parents of spinal muscular atrophy patients: a characteristic background of spinal muscular atrophy in Japan?

Most spinal muscular atrophy (SMA) patients lack the survival motor neuron gene (SMN). However, the patients retain at least one copy of the cBCD541 gene (BCD), which is highly homologous with SMN. Here, we determined the SMN/BCD copy number ratios (the S/B ratios) of 12 parents of Japanese SMA patients with a homozygous SMN deletion, using competitive oligonucleotide priming polymerase chain reaction. We identified an S/B ratio of 2 in 25% of the parents examined, whereas less than 2% of parents of SMA patients in Western populations have an S/B ratio of 2. The high incidence of an S/B ratio of 2 in Japanese parents of SMA patients may reflect the characteristic genetic background of SMA in Japan.

Female↗
PubMed1999

A simple explanation for a case of incompatibility with the reading frame theory in Duchenne muscular dystrophy: failure to detect an aberrant restriction fragment in Southern blot analysis.

According to the translational reading frame theory, Duchenne muscular dystrophy (DMD) patients harbor out-of-frame deletion mutations in the dystrophin gene. We identified a Japanese DMD case who appeared to have an in-frame deletion of exons 46-54 that was disclosed by Southern blot analysis using a dystrophin cDNA as a probe. Analysis of dystrophin mRNA in skeletal muscle revealed the presence of an out-of-frame deletion of exons 46-53. In agreement with this result, the region encompassing exon 54 could be amplified from genomic DNA by polymerase chain reaction (PCR). Furthermore, re-analysis by Southern blot using an exon specific probe disclosed that a HindIII fragment containing exon 54 was present at aberrant size, leading to the incorrect conclusion that exon 54 had been deleted. Thus, this particular DMD case does not constitute an exception to the reading frame theory.

Blotting, Southern↗
PubMed1999

Molecular basis of glucose-6-phosphate dehydrogenase deficiency among Filipinos.

BACKGROUND: Multiplex polymerase chain reaction (PCR) using multiple tandem forward primers and a common reverse primer (MPTP) was recently established as a comprehensive scanning system for mutations in X-linked recessive diseases. In this report, MPTP was tested to scan for mutations of the glucose-6-phosphate dehydrogenase (G6PD) gene. METHODS: Mutations in exon 11 of the G6PD gene were screened by MPTP in five unrelated Filipino cases with G6PD deficiency. RESULTS: Of the five patients, four screened positive for a mutation in the gene. Sequencing of the amplified products confirmed that three cases had a C-->T substitution at nucleotide (n.t.) 1360 (C1360T) resulting in an amino acid change of arginine to cysteine at position 454 and one had a silent single base substitution C-->T at nucleotide 1311. CONCLUSION: Our results document a C1360T mutation of the G6PD gene in three Filipino patients in the Philippines.

Amino Acid Sequence↗
PubMed1999

Magnolol inhibits leukotriene synthesis in rat basophilic leukemia-2H3 cells.

We have observed an inhibitory action of magnolol on the production of leukotriene (LT) C4 and LTB4, important lipid mediators in allergy and inflammation. IgE- and A23187-stimulated production of LTC4 and LTB4 was measured by radio-immunoassay (RIA) in the absence or presence of various concentrations of magnolol in intact rat basophilic leukemia (RBL)-2H3 cells. Magnolol dose-dependently inhibited synthesis of LTC4 and LTB4. Magnolol inhibited the IgE-mediated increase of intracellular calcium ion concentration, resulting in the inhibition of cytosolic phospholipase A2 (cPLA2) and possibly 5-lipoxygenase (5-LO), both calcium ion-dependent enzymes. In cell-free studies magnolol inhibited LTC4 synthase activity. LTA4 hydrolase activity was only inhibited at the higher concentration (2.5 x 10(-5)M). These results indicate that magnolol inhibits production of LTs by inhibiting PLA2, 5-LO, LTC4 synthase and LTA4 hydrolase which are essential for LT-synthesis. Magnolol may have anti-allergic effect by blocking LT-synthesis.

Animals↗
PubMed1999

Circular dystrophin RNAs consisting of exons that were skipped by alternative splicing.

Exon skipping by alternative splicing and circular RNA formation are proposed to be interrelated events. Since multiple patterns of alternative splicing have been demonstrated in both the 5' and 3' regions of the dystrophin gene, the dystrophin transcript in skeletal muscle cells provides a model system in which this idea is tested. Nine circular RNAs that were expected to result from known exon skipping patterns in the 5' region of this gene were in fact identified, but three other circular RNAs expected to result from other known exon skipping reactions in this region could not be detected. The identification of two unexpected circular RNAs led to the discovery of two novel alternative splicing reactions. One circular RNA originating in the 3' region of the gene was identified but it lacked one small sized exon compared with the expected exon structure. Circular RNAs from the 5' region of the dystrophin gene could not be detected in Duchenne muscular dystrophy patients who have deletions of one or more exons in this segment of the gene, even though alternative splicing products were identified. These results showed that circular RNA formation is not necessarily linked to exon skipping and suggest that an undetermined factor regulates circular RNA formation.

Alternative Splicing↗
PubMed1999

Quantitative EEG analyses and surgical outcome after corpus callosotomy.

PURPOSE: To clarify the relation between quantitative electroencephalogram (EEG) findings and outcome following corpus callosotomy (CC). METHODS: The degree of bilateral synchrony and morphologic similarity of spike-wave discharges was analyzed by using a cross-correlation analysis and the measurements of amplitude differences between bilateral homologous regions in 22 patients who underwent anterior CCs for intractable symptomatic generalized epilepsies (SGE; 17 patients) and frontal lobe epilepsy (five patients). RESULTS: Interictal generalized synchronous spike-wave (GSSW) bursts in the SGE patients were disrupted and changed to unilateral spike-waves (USWs) in 11 patients and to bilaterally independent spike-waves (BISWs) in six. The USW group had better surgical outcome than the BISW group. Preoperatively, the USW group had significantly lower interhemispheric synchrony (IS) and fewer regional changes in the side leading in time and the side dominant for amplitude, suggesting unilaterally predominant epileptogenesis that triggered the secondary bilateral synchrony. Postoperatively, the BISW group had a more marked reduction in IS because of independent discharges from bilateral epileptogenic areas, and the USW group had a greater amplitude difference because of unilateralized spike-waves. In addition, an excellent surgical outcome was related to (a) the preoperative degree of the morphologic similarity of the bilateral spike-waves (only a small variation during a burst of spike-waves) and the few instances of regional changes in the side leading in time and in the side dominant for amplitude; and (b) to large postoperative amplitude differences. CONCLUSION: Preoperative quantitative EEG analyses enabled us to predict the underlying conditions of epileptogenesis and the surgical outcomes in patients undergoing CC.

Adolescent↗
PubMed1999

Hybrid survival motor neuron genes in Japanese patients with spinal muscular atrophy.

Spinal muscular atrophy (SMA) is a frequently occurring autosomal recessive disease, characterized by the degeneration of spinal cord anterior horn cells, leading to muscular atrophy. Most SMA patients carry homozygous deletions of the telomeric survival motor neuron gene (SMN) exons 7 and 8. In the study presented here, we examined 20 Japanese SMA patients and found that 4 of these patients were lacking in telomeric SMN exon 7, but retained exon 8. In these 4 patients, who exhibited all grades of disease severity, direct sequencing analysis demonstrated the presence of a hybrid SMN gene in which centromeric SMN exon 7 was adjacent to telomeric SMN exon 8. In an SMA family, a combination of polymerase chain reaction and enzyme-digestion analysis and haplotype analysis with the polymorphic multicopy marker Agl-CA indicated that the patient inherited the hybrid gene from her father. In conclusion, hybrid SMN genes can be present in all grades of disease severity and inherited from generation to generation in an SMA family.

Adult↗
PubMed1999

Induction of cytosolic phospholipase A2 and prostaglandin H2 synthase-2 by lipopolysaccharide in human polymorphonuclear leukocytes.

Polymorphonuclear leukocytes (PMNs) produce arachidonic acid (AA) metabolites including thromboxane A2 (TXA2). These cells are the first line of defense against bacterial invasion, which often causes endotoxin shock. TXA2 which plays an important role in the pathogenesis of endotoxin shock is synthesized by three consecutive enzyme activation, cytosolic phospholipase A2 (cPLA2), prostaglandin H2 synthase (PHS type 1 and type 2) and TXA2 synthase. Among them, cPLA2- and PHS-2 activity is known to be transcriptionally and/or posttranscriptionally up-regulated by various bioactive substances including lipopolysaccharide (LPS), a bacterial endotoxin, in many cell types. We investigated the action of LPS on TXA2 synthesis in human PMNs. A23187-stimulated production of thromboxane B2 (TXB2, a stable metabolite of TXA2), assayed by specific radioimmunoassay (RIA), was significantly increased from 566.7+/-44.1 pg/10(6) cells to 966.7+/-44.1 pg/10(6) cells (p<0.05) after 6 h-exposure to LPS at the concentration of 100 ng/ml. Messenger RNA for PHS-2, PHS-1, TXA2 synthase and cPLA2, which was assessed by reverse transcription-polymerase chain reaction (RT-PCR), was expressed in PMNs without LPS stimulation. Although PHS-2 was putatively an inducible enzyme, abundance of mRNA for PHS-2 in PMNs without LPS stimulation was detectable. Messenger RNA abundance for PHS-2 and cPLA2, but not for PHS-1 and TXA2 synthase, was enhanced by LPS-treatment, indicating that the increased production of TXB2 was attributable to the up-regulation of cPLA2 and PHS-2. We conclude that (1) PHS-2 plays a more important role than PHS-1 in the production of TXA2 in human PMNs and (2) TXA2 synthesis in human PMNs is transcriptionally up-regulated by new induction of cPLA2 as well as PHS-2, when the cells encounter endotoxin producing bacteria.

Aspirin↗
PubMed1999

A novel deletion of the dystrophin S-promoter region cosegregating with mental retardation.

A contiguous deletion of the S-promoter/first S exon and its downstream exon 56 of the dystrophin gene was identified in a Japanese dystrophinopathy family in which two brothers and their half brother were affected. Characteristically, severe mental retardation cosegregated with the deletion even though they grew up in different environments. Furthermore, mild cerebral atrophy was observed by CT scan and MRI in the eldest brother.

Adult↗
PubMed1999

Female adnexal tumour of probable Wolffian origin: MR findings.

Female adnexal tumour of probable Wolffian origin is a rare tumour that arises from remnants of the Wolffian duct. Clinical and pathological findings of this tumour have been documented, but the MR findings have not been previously reported. We report the MRI features of an adnexal tumour of probable Wolffian origin.

Adenoma↗
PubMed1999

Angiotensinogen and angiotensin-converting enzyme genotypes, and day and night blood pressures in elderly Japanese hypertensives.

There are inconsistent reports that the angiotensinogen (ATG) variant Met235-->Thr (T235) allele and angiotensin-converting enzyme (ACE) insertion/deletion (I/D) variants are associated with hypertension and related target organ damage. Both high blood pressure (BP) and abnormal diurnal BP variation patterns are related to target organ damage, but it is not known whether the above genetic variants of the renin-angiotensin system are related to 24 h BP and the diurnal BP pattern in Japanese. We studied the association of the ATG T235 allele and ACE D allele with 24 h BP and diurnal BP variation in 235 of 262 consecutive untreated (or off medication) elderly Japanese hypertensives who underwent 24 h ambulatory BP monitoring. There was no significant association between the T235 or ACE D allele with office BP, but the T235 allele was significantly associated with 24 h BP and day BP, and the D allele was significantly associated with increased 24 h BP, day BP, and night BP. There were no effects of the T235 or D alleles on any BP parameters. Those with white-coat hypertension had a significantly lower T235 allele frequency (0.68) than those with sustained hypertension (0.79, p=0.010), but the difference in D allele frequency was marginal (0.30 vs. 0.38, p=0.057). In conclusion, in elderly Japanese hypertensive individuals, both the ATG T 235 and ACE D alleles are associated with increased 24 h BP and day BP, while only the ACE D allele is associated with increased night BP.

Aged↗
PubMed1999

Discontinuous incremental threshold loading test: measure of respiratory muscle endurance in patients with COPD.

STUDY OBJECTIVE: To assess the discontinuous incremental threshold loading (DC-ITL) test as a measure of respiratory muscle endurance for patients with COPD in terms of perceived breathing difficulty, reliability, and validity. DESIGN: The DC-ITL test was repeated three times at weekly intervals under identical test conditions. SETTING: Clinical research laboratory. PATIENTS: Forty-eight patients with moderate to severe COPD. MEASUREMENTS AND RESULTS: Rating of perceived breathing difficulty (RPBD) was measured at the end of each stage of the DC-ITL test with a Borg category-ratio scale. The maximal inspiratory pressure (PImax) was measured before and after the DC-ITL test. Breathing patterns were measured during the DC-ITL test. The mean (+/-SD) for RPBD at the maximal load was 6.3 (3.1), 6.6 (2.8), and 6.7 (2.7) for visits one, two, and three, respectively (not significant). The mean relative maximal load for the DC-ITL test (peak mouth pressure as a percent of PImax) at the last completed stage was 59+/-23%, 62+/-20%, and 63+/-19% for visits one, two, and three, respectively (not significant). Test-retest reliability was r1,2=0.82 and r2,3=0.69 for relative maximal load and r1,2=0.90 and r2,3=0.90 for absolute maximal load (peak mouth pressure). Tidal volume decreased (p < 0.01) and respiratory rate increased (p < 0.01) from the next-to-the-last to the last completed stage. PImax decreased after the DC-ITL test (p < 0.01). CONCLUSIONS: Moderate breathing difficulty was experienced during the DC-ITL test. The test was reliable and the results of this study support its validity as a measure of respiratory muscle endurance.

Aged↗
PubMed1999

Development and application of a system for analysis of mixed cultures of microorganisms.

Development and application of a system for real-time quantitative assessment of individual cell activities in a mixed culture system was investigated. This was based on a concept that the activities of individual cells in a mixed culture can be assessed if the cells are physically separated (in separate compartments) in a vessel while the culture conditions, including the broth components, are maintained the same in all the compartments during the cultivation. On this basis, three different apparatus (M-1, M-2, and M-3) were constructed using various types of membranes. In terms of mass transfer characteristics and membrane fouling, the M-3 apparatus was the most effective system for analysis of mixed cultures at high cell densities. With the M-3 apparatus, the interrelationships between two alcohol-producing strains (Saccharomyces cerevisiae and Zymomonas mobilis) under anaerobic and aerobic conditions were studied. Under anaerobic condition, except for possible competition for nutrients, there were no significant effects of the activities of one microorganism on the other. However, under aerobic condition, amensalism was observed because acetaldehyde that was produced by Z. mobilis inhibited the growth of S. cerevisiae.

Aerobiosis↗
PubMed1999

Microvascular changes after placement of titanium implants: scanning electron microscopy observations of machined and titanium plasma-sprayed implants in dogs.

BACKGROUND: The purpose of this study was to clarify the osseointegration process of titanium implants through study of the vascular architecture and bone apposition. The smooth machined-surface implant is tightly fixed to the bone by its threads. The rough titanium plasma-sprayed (TPS) coated implants give a scaffold for new bone. METHODS: Twelve beagle dogs were used, and 2 surface types of implants were inserted in the mandible. Vascular injection was given 14, 30, and 120 days after surgery. The soft tissue was digested by proteinase solution, and specimens were examined by scanning electron microscope (SEM). RESULTS: Fourteen days after placement of machined implants, new vessels could be seen branching out from the vascular network of the bone marrow. In TPS implants, a vascular network was seen between the bone-implant interface. At 30 days, the vessels were arranged in a groove corresponding to the machined fixture. With TPS implants, new bone was visible along the surface of the fixture, and the vascular network was buried in the bone. At 120 days after placement of machined implants, bone had formed a smooth surface. A few blood vessels were arranged along the bone surface. With TPS implants, a rough bone surface and flat vessels were observed on its surface. CONCLUSIONS: Implants become osseointegrated in different ways, depending on their structures and the characteristics of their surfaces. From the microcirculation point of view, the vessels are an important factor for the remodeling of bone.

Alveolar Process↗