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Biomedical subjects

M Matsui

Publications and source records attributed to M Matsui.

At least 91 records · Page 5Linked to original sources
PubMed2000

Complex regional pain syndrome in childhood: report of three cases.

We describe three patients with the limb pain of complex regional pain syndrome (CRPS) in childhood with autonomic nervous system function involvement. Their autonomic nerve abnormality was non-invasively examined by means of laser doppler flowmetry (LDF) and a sympathetic skin response (SSR) test. In one it was resolved with physiotherapy, but the others needed epidural anesthesia for pain control. Though CRPS used to be recognized as a refractory disorder in adults, childhood cases have been found in recent years, generally having a better prognosis than adult ones. However, even in the children, the prognosis or responses to the same therapy vary, and there are progressive and refractory cases. CRPS should be considered as a differential diagnosis of unexplained persistent limb pain even in childhood for early and appropriate management.

Adolescent↗
PubMed2000

Influence of aging and cell senescence on telomerase activity in keratinocytes.

Telomeres, which exist in eukaryotic chromosome ends in specialized G-rich TTAGGG structure, protect the ends from degradation or fusion. On the other hand, telomerase is a ribonucleoprotein complex enzyme that synthesizes TTAGGG repeat sequences at the ends of eukaryotic chromosomes. Previous studies suggested that telomere length and telomerase activity cooperate in aging and immortalization of cells. Here, we examined telomere length and telomerase activity in keratinocytes from seven human subjects, including a patient with Werner's syndrome. Telomere length in keratinocytes from healthy individuals was shortened with aging. However, telomerase activity from an individual aged 42 years was reduced, compared with that from a 0 year old individual. Passages of keratinocytes reduced telomerase activity significantly in F2 and F3 keratinocytes from 0 and 42 year old individuals. Withdrawal of either EGF or amphiregulin from medium resulted in down-regulation of telomerase activity. These results suggest that telomere length and telomerase activity in primary cultured keratinocytes may be one of the parameters for cell senescence. However, there remain obscure factors such as ultraviolet-B radiation and growth factors.

Adult↗
PubMed2000

Antioxidative activity in the pericarp and seed of Japanese pepper (Xanthoxylum piperitum DC).

The antioxidative activity of the dried pericarp and seed of Japanese pepper was studied. The ethyl acetate extract from the pericarp and the methanol extract from the seed showed strong antioxidative activity against linoleic acid by the ferric thiocyanate and thiobarbituric acid (TBA) methods. Japanese pepper contained 3.9 and 2.9 mg/100 g of dry weight (dw) of tocopherols in the pericarp and seed, respectively, alpha-Toc in the former constituting 82% of total tocopherol and gamma-Toc in the latter constituting 96%. Arbutin and magnoflorine were isolated as antioxidants and their chemical structures determined by instrumental analyses. The contents of arbutin evaluated as the trifluoroacetate derivative by GC-MS were 35 and 3.0 mg/100 g of dw in the pericarp and seed, respectively. Magnoflorine was present only in the seed, and not in the pericarp. Both arbutin and magnoflorine exhibited antioxidative activity against linoleic acid and radical-scavenging activity against the DPPH radical.

Antioxidants↗
PubMed2000

Ovarian leiomyosarcoma: an autopsy case report.

Primary non-specific sarcoma of the ovary is extremely rare, and only 22 reported cases of pure leiomyosarcoma (LMS) are known to the authors. We present an autopsy case of a primary ovarian leiomyosarcoma in a 73-year-old woman. She had noticed an abdominal mass after difficulty in defecating for several months. The excision of tumor with bilateral salpingo-oophorectomy and hysterectomy was carried out. A diagnosis of pure leiomyosarcoma of the left ovary was made on pathological examination with immunohistochemistry. Adjuvant radio-chemotherapy was not given. At 18 months' follow up, abdomino-pelvic sonography revealed an abdominal tumor and hepatic metastasis. The patient died 3.5 years after the initial surgery. The post-mortem examination revealed a peritoneal recurrent tumor and extensive distant metastases of the liver, lungs, pancreas, gastric mucosa, muscle and skin. The prognosis of the ovarian LMS is poor from the pertinent literature. Several prognostic indicators on histology including mitotic activity, proliferative activity and p53 status of the tumor are discussed.

Aged↗
PubMed2000

Inhibitory effects of green tea and grape juice on the phenol sulfotransferase activity of mouse intestines and human colon carcinoma cell line, Caco-2.

Tea and fruit juices are beverages consumed daily all over the world. The present study reports the inhibitory effects of these beverages on the activity of mammalian intestinal phenol sulfotransferases (P-STs). Green tea strongly inhibited the E. coli-expressed mouse intestinal P-ST activity in vitro. (-)-Epigallocatechin gallate (EGCG) was found to be the most potent inhibitor among the catechins tested (IC50=0.93 microM). (-)EGCG also inhibited the P-ST activity of the human colon carcinoma cell line, Caco-2. Kinetic analysis showed that the inhibition was competitive. Among fruit juices examined (apple, grape, grapefruit and orange), grape juice exhibited the most potent inhibitory action on the P-ST activity of mouse intestines and human colon carcinoma cells. The inhibitory activity of grape juice was located mainly in the skin and seeds. Flavonols, such as quercetin and kaempferol, inhibited the P-ST activity at low concentrations. These observations suggest the possible inhibition of P-ST activity in human intestines by green tea or grape juice.

Animals↗
PubMed2000

Sulfotransferases in a human colon carcinoma cell line, Caco-2.

We investigated the expression of sulfotransferases (STs) in the human colon carcinoma cell line, Caco-2, which is widely used as a human intestine model for orally administered drugs. By reverse transcription-polymerase chain reaction (RT-PCR), we could detect mRNA expressions of phenol STs (P-ST), hydroxysteroid ST (HS-ST) and estrogen ST (E-ST). Treatment with 1,25-dihydroxyvitamine D3, which induces CYP3A4 expression in Caco-2 cells, did not affect the ST expression of the cells. We detected significant P-ST activity toward 2-naphthol and dopamine in the cell extract. We also observed detectable HS-ST activity toward dehydroepiandrosterone (DHEA), but no E-ST activity toward beta-estradiol was observed in the extract. Analyses by RT-PCR and separation of P-ST activities on ion-exchange column chromatography showed that the thermolabile monoamine phenol sulfotransferase (M-PST) is dominant in Caco-2 cells.

Arylsulfotransferase↗
PubMed2000

Development of a digital image database for chest radiographs with and without a lung nodule: receiver operating characteristic analysis of radiologists' detection of pulmonary nodules.

OBJECTIVE: We developed a digital image database (www.macnet.or.jp/jsrt2/cdrom_nodules.html ) of 247 chest radiographs with and without a lung nodule. The aim of this study was to investigate the characteristics of image databases for potential use in various digital image research projects. Radiologists' detection of solitary pulmonary nodules included in the database was evaluated using a receiver operating characteristic (ROC) analysis. MATERIALS AND METHODS: One hundred and fifty-four conventional chest radiographs with a lung nodule and 93 radiographs without a nodule were selected from 14 medical centers and were digitized by a laser digitizer with a 2048 x 2048 matrix size (0.175-mm pixels) and a 12-bit gray scale. Lung nodule images were classified into five groups according to the degrees of subtlety shown. The observations of 20 participating radiologists were subjected to ROC analysis for detecting solitary pulmonary nodules. Experimental results (areas under the curve, Az) obtained from observer studies were used for characterization of five groups of lung nodules with different degrees of subtlety. RESULTS: ROC analysis showed that the database included a wide range of various nodules yielding Az values from 0.574 to 0.991 for the five categories of cases for different degrees of subtlety. CONCLUSION: This database can be useful for many purposes, including research, education, quality assurance, and other demonstrations.

Adult↗
PubMed2000

The relation between tendency for psychopathology and reduced frontal brain volume in healthy people.

OBJECTIVE: We hypothesized that tendency toward psychopathology is associated with lower frontotemporal volumes. BACKGROUND: Although there is considerable evidence for structural abnormalities in patients with major psychiatric disorders and increased recognition that neural substrates may underlie individual differences in personality, there have been no studies in healthy people attempting to relate personality to volumetric measures of brain structure. METHOD: We used magnetic resonance imaging with an advanced method for automated segmentation of cranial compartments to gray matter, white matter, and cerebrospinal fluid. We examined the relation between frontal and temporal lobe volumes and Minnesota Multiphasic Personality Inventory measures of tendency toward psychopathology in 59 healthy individuals. RESULTS: As hypothesized, higher scores on the clinical scales were associated with lower average frontal lobe volume. When the sample was divided according to sex, however, these correlations were significant in men (n = 29) but not in women (n = 30). The highest correlation was observed between lower frontal white matter volume in men and high schizophrenia scale score (r[27] = -0.59, p <0.001). CONCLUSIONS: The findings suggest that personality dimensions in healthy people can be linked to neural substrates, which can potentially serve as endophenotypic markers of disposition to psychopathology. The sexually dimorphic effects are consistent with gender-related differences in the clinical manifestations of psychiatric disorders and may suggest sex hormone modulation of the psychopathologic processes.

Adult↗
PubMed2000

[Clinical features of children with athetotic cerebral palsy in relation to their gestational age at birth].

We present here 38 patients with athetotic cerebral palsy who has trained in our clinic in recent 5 years. The mean age was 4 years and 4 months. In preterm cases, their gestational ages ranged from 27 weeks to 36 weeks, less than 31 weeks in 74%. MRI showed periventricular leukomalacia in 75%. Their clinical picture was mixed quadriplegia with athetosis and spasticity. Half of the cases were profoundly handicapped in motor ability. Fifteen cases had been born in term. Sixty percent of them had a non-mixed type of cerebral palsy. Five cases had no remarkable risk factor during the perinatal period. Six cases were able to walk with or without support. Hypoxic-ischemic encephalopathy was the main cause of athetotic cerebral palsy in recent years. Twin pregnancy was also an important risk factor, especially in preterm infants. MRI could detect lesions in the thalamus or the basal ganglia in only 17% of the 36 cases examined.

Brain↗
PubMed1999

The RING finger motif of photomorphogenic repressor COP1 specifically interacts with the RING-H2 motif of a novel Arabidopsis protein.

The constitutive photomorphogenic 1 (COP1) protein of Arabidopsis functions as a molecular switch for the seedling developmental fates: photomorphogenesis under light conditions and skotomorphogenesis in darkness. The COP1 protein contains a cysteine-rich zinc-binding RING finger motif found in diverse groups of regulatory proteins. To understand the role of the COP1 RING finger in mediating protein-protein interaction, we have performed a yeast two-hybrid screen and isolated a novel protein with a RING-H2 motif, a variant type of the RING finger. This protein, designated COP1 Interacting Protein 8 (CIP8), is encoded by a single copy gene and localized to cytosol in a transient assay. In addition to the RING-H2 motif, the predicted protein has a C4 zinc finger, an acidic region, a glycine-rich cluster, and a serine-rich cluster. The COP1 RING finger and the CIP8 RING-H2 domains are sufficient for their interaction with each other both in vitro and in yeast, whereas neither motif displayed significant self-association. Moreover, site-directed mutagenesis studies demonstrated that the expected zinc-binding ligands of the RING finger and RING-H2 fingers are essential for their interaction. Our findings indicate that the RING finger motif, in this case, serves as autonomous protein-protein interaction domain. The allele specific effect of cop1 mutations on the CIP8 protein accumulation in seedlings indicates that its stability in vivo is dependent on the COP1 protein.

Amino Acid Sequence↗
PubMed1999

Identification of thioredoxin-binding protein-2/vitamin D(3) up-regulated protein 1 as a negative regulator of thioredoxin function and expression.

Recent works have shown the importance of reduction/oxidation (redox) regulation in various biological phenomena. Thioredoxin (TRX) is one of the major components of the thiol reducing system and plays multiple roles in cellular processes such as proliferation, apoptosis, and gene expression. To investigate the molecular mechanism of TRX action, we used a yeast two-hybrid system to identify TRX-binding proteins. One of the candidates, designated as thioredoxin-binding protein-2 (TBP-2), was identical to vitamin D(3) up-regulated protein 1 (VDUP1). The association of TRX with TBP-2/VDUP1 was observed in vitro and in vivo. TBP-2/VDUP1 bound to reduced TRX but not to oxidized TRX nor to mutant TRX, in which two redox active cysteine residues are substituted by serine. Thus, the catalytic center of TRX seems to be important for the interaction. Insulin reducing activity of TRX was inhibited by the addition of recombinant TBP-2/VDUP1 protein in vitro. In COS-7 and HEK293 cells transiently transfected with TBP-2/VDUP1 expression vector, decrease of insulin reducing activity of TRX and diminishment of TRX expression was observed. These results suggested that TBP-2/VDUP1 serves as a negative regulator of the biological function and expression of TRX. Treatment of HL-60 cells with 1alpha, 25-dihydroxyvitamin D(3) caused an increase of TBP-2/VDUP1 expression and down-regulation of the expression and the reducing activity of TRX. Therefore, the TRX-TBP-2/VDUP1 interaction may be an important redox regulatory mechanism in cellular processes, including differentiation of myeloid and macrophage lineages.

Animals↗