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Biomedical subjects

K Matsuda

Publications and source records attributed to K Matsuda.

At least 145 records · Page 8Linked to original sources
PubMed2000

Clinical significance of MUC1 and MUC2 mucin and p53 protein expression in colorectal carcinoma.

BACKGROUND: Up-regulation of MUC1, down-regulation of MUC2 and p53 overexpression are seen in colorectal carcinomas. However, there have been few reports about the associations between MUC1, MUC2 and p53 expression and metastatic potential. The aim of this study was to investigate MUC1, MUC2 and p53 expression in colorectal carcinoma with special reference to regional and distant metastasis. METHODS: Eighty-six colorectal carcinomas were collected from patients undergoing tumor resection. Sections were used for MUC1, MUC2 and p53 immunostaining. Cancers were regarded as MUC1 or MUC2 positive when the positive cells were beyond 30% of cancer cells. Cancers with diffuse or nested patterns were regarded as having p53 overexpression. RESULTS: Of 86 cancers, 37 (43%) were MUC1 positive, 28 (33%) were MUC2 positive and 59 (69%) showed p53 overexpression. A difference was observed only in the frequency of MUC1 positivity with respect to depth of tumor invasion. Neither depth of tumor invasion nor histological differentiation had a positive correlation with MUC1, MUC2 and p53 overexpression. The frequency of MUC1 positive cells in Dukes' C and D tumors was significantly higher than that in Dukes' A and B tumors. The frequency of MUC1 positivity in tumors with hepatic involvement was significantly higher than that in tumors without hepatic involvement (100 vs 39%; p < 0.01). There was no difference in the frequency of MUC2 or p53 positivity in Dukes' stage or hepatic metastasis. MUC1 immunoreactivity of the surface was identical with that of the whole tumor in 81% (70/86) of carcinomas, MUC 2 in 87% and p53 in 100%. CONCLUSIONS: The results suggest that up-regulation of MUC1 is involved in the progression from the non-metastatic to the metastatic stage and that p53 abnormality is not directly involved in it. The data also imply that immunostaining of preoperative biopsy samples is useful for evaluating the immunoreactivity of the whole tumor.

Adult↗
PubMed2000

Monoclonal antibody against Mycoplasma fermentans-specific aminoglycoglycerolipid.

Previously, we reported that Mycoplasma fermentans has specific antigens (phosphocholine-containing glycoglycerolipids: GGPL-I and GGPL-III) and discussed the possibility of their pathogenic role. In this paper, we report the characterization of a monoclonal antibody (MF-III-1) specific to GGPL-III (phosphocholine-containing aminoglycoglycerolipid) using methods of electron microscopy, immunofluorescence cell surface staining, laser scanning microscopy, immunoelectron microscopy, and thin-layer chromatography immunostaining. The MF-III-1 antibody specifically recognized M. fermentans attached to the surface of HTLV-I-infected human helper T-cells, and it did not cross-react with other lipids nor with human T-cell antigens. Since MF-III-1 distinguishes GGPL-III from GGPL-I, the binding site may include a serinol (2-amino-1,3-propanediol) residue of GGPL-III. MF-III-1 is useful for the in vitro study of M. fermentans, and may also be useful as a tool for the study of the involvement of M. fermentans in human diseases.

Animals↗
PubMed2000

Electroclinical and magnetoencephalographic analysis of epilepsy in patients with congenital bilateral perisylvian syndrome.

PURPOSE: Epilepsies in four patients with congenital bilateral perisylvian syndrome (CBPS) were studied electroclinically and by magnetoencephalography (MEG) to determine whether cortical dysplasia associated with this syndrome is epileptogenic. METHODS: We studied three women and one man (mean +/- SD age 30.8 +/- 3.4 years) with a diagnosis of CBPS based on magnetic resonance imaging (MRI). All had drug-resistant epilepsy. In addition to electroclinical analysis, the distribution of equivalent-current dipoles (ECDs) analyzed from MEG signals was examined. RESULTS: Patient 1 had left-sided parietal lobe epilepsy and ECDs clustered in the left temporoparietal lobe. Patient 2 had bilateral, independent temporoparietal lobe epilepsy, and ECDs were found in both hemispheres, with clustering in the right temporoparietal lobe but not in the left hemisphere. Patient 3 presumably had parietal lobe epilepsy with unidentified focus side and ECDs clustered in the left parietal and right temporal lobes. Patient 4 had symptomatic generalized epilepsy, and ECDs were observed in both hemispheres without clustering. In the three patients who had partial epilepsy (patients 1-3), clusters of ECDs overlaid the perisylvian dysplasia and were not found elsewhere. CONCLUSIONS: Patients with CBPS may have either symptomatic partial epilepsy or symptomatic generalized epilepsy, and those with partial epilepsy are likely to have temporoparietal foci. In addition, cortical dysplasia is closely related to the generation of partial seizures and may be epileptogenic per se. However, this study did not elucidate the relationship between cortical dysplasia and CBPS-generated generalized epilepsy.

Adult↗
PubMed2000

Retrospective radiographic analysis of nonpedunculated colorectal carcinomas with special reference to tumor doubling time and morphological change.

OBJECTIVE: Our aim was to characterize the development of nonpedunculated colorectal carcinomas by retrospective radiographic analysis, with special reference to tumor doubling time and morphological change. METHODS: Eleven colorectal carcinomas, which were observed for >6 months by barium enema examinations, were collected and retrospectively reviewed. There were five early and six advanced carcinomas, including submucosally invasive, superficial depressed carcinomas. RESULTS: Mean diameter of lesions at initial barium enema examination was 13.5 mm (early, 10.4 mm; advanced, 16.0 mm) and that at final barium enema examination was 30.9 mm (early, 18.2 mm; advanced, 41.5 mm). Initial morphology of the lesions was superficial in three, sessile in seven, and semipedunculated in 1. There was no pedunculated lesion. Macroscopic morphology of the five early carcinomas was superficial depressed (IIc) in two cases, mostly depressed but partly elevated (IIc+IIa) in one case, and superficial elevated with a depressed component (IIa+IIc) in two cases; all of the advanced carcinomas were of the ulcerated type. Mean doubling time was 6.8 months (early, 9.4 months; advanced, 4.7 months). Early carcinomas had significantly longer doubling times than advanced carcinomas (p = 0.017, Wilcoxon's text). The lesions with the longest doubling times were superficial depressed lesions. CONCLUSIONS: Early carcinomas have longer doubling times than advanced carcinomas. Most nonpedunculated colorectal carcinomas grow without significant morphological changes. Superficial depressed type tumors grow slowly, maintaining their macroscopic morphology.

Adult↗
PubMed2000

Model equation for strongly focused finite-amplitude sound beams

A model equation that describes the propagation of sound beams in a fluid is developed using the oblate spheroidal coordinate system. This spheroidal beam equation (SBE) is a parabolic equation and has a specific application to a theoretical prediction on focused, high-frequency beams from a circular aperture. The aperture angle does not have to be small. The theoretical background is basically along the same analytical lines as the composite method (CM) reported previously [B. Ystad and J. Berntsen, Acustica 82, 698-706 (1996)]. Numerical examples are displayed for the amplitudes of sound pressure along and across the beam axis when sinusoidal waves are radiated from the source with uniform amplitude distribution. The primitive approach to linear field analysis is readily extended to the case where harmonic generation in finite-amplitude sound beams becomes significant due to the inherent nonlinearity of the medium. The theory provides the propagation and beam pattern profiles that differ from the CM solution for each harmonic component.

Journal Article↗
PubMed2000

In vitro apatite induction by phosphophoryn immobilized on modified collagen fibrils.

Noncollagenous phosphoproteins that interact with type I collagen are thought to nucleate the mineral phase to collagen network of mineralized tissues. Previously, we found that phosphophoryn cross-linked to type I collagen was an effective nucleator of apatite. Here, we investigated the potential role of collagen telopeptide structure on this nucleation. We used pepsin and sodium borohydride (NaBH4) to modify the telopeptide region and reducible cross-links in the collagen fibrils and determined the effect on mineral induction by phosphophoryn cross-linked to it. The amount of phosphophoryn cross-linked to NaBH4-reduced collagen fibrils was higher than that to intact (unmodified) collagen fibrils. However, the amount of phosphophoryn cross-linked to collagen that lacked the telopeptides (atelocollagen) was 25% of that cross-linked to intact collagen fibrils. Each preparation was incubated at 37 degrees C in metastable calcium phosphate solutions that did not spontaneously precipitate. Apatite was induced by phosphophoryn cross-linked to intact collagen fibrils at 15.0 h whereas phosphophoryn cross-linked to reduced collagen fibrils induced apatite formation after 10.9 h. Enough phosphophoryn was cross-linked to atelocollagen to induce mineral formation, but it did not. The failure of the phosphophoryn-atelocollagen complex to nucleate mineral might have been caused by a cross-linking pattern in the helical portion of the collagen molecule that did not promote the growth of the calcium-phosphate clusters into nuclei. The present study indicates that the telopeptide domains of type I collagen play a role in the interaction with phosphophoryn, which is critical for the nucleation process.

Animals↗
PubMed2000

Effect of chronic treatment with perindopril on endothelium-dependent relaxation of aorta and carotid artery in SHRSP.

Endothelium-dependent relaxation of aorta and carotid artery from stroke-prone spontaneously hypertensive rats (SHRSP) and the effect of chronic treatment of SHRSP with perindopril, an angiotensin converting enzyme inhibitor, on endothelium-dependent relaxation were studied. Endothelium-dependent relaxation was induced by acetylcholine (ACh) in preparations of SHRSP and normotensive Wistar Kyoto rats (WKY) precontracted with noradrenaline. The ACh-induced relaxation in both preparations was abolished by L-nitroarginine. The ACh-induced relaxation was impaired in preparations from SHRSP and contraction was observed at high concentrations of ACh. In the presence of indomethacin, impairment of endothelium-dependent relaxation in SHRSP was minimized and the contraction was inhibited. The relaxation with sodium nitroprusside did not differ between the preparations from WKY and SHRSP. Treatment of SHRSP with perindopril (2 mg/kg/day) for 6 weeks decreased systolic blood pressure and improved the ACh-induced relaxation of aorta and carotid artery. The treatment inhibited the contraction by higher concentrations of ACh in the presence of L-nitroarginine. These results indicate that the impairment of endothelium-dependent relaxation in aorta and carotid artery of SHRSP may be caused by the reduced availability of nitric oxide. The perindopril-treatment may prevent these changes in SHRSP.

Acetylcholine↗
PubMed2000

[Terrestrial adaptation and diversity of the kidney functions in the evolution of vertebrates, Amphibia].

The Amphibia bridge the phyletic gap between the aquatic fishes and the terrestrial vertebrates. This transition has involved many interesting changes of metabolisms. In this short review, we have attempted to summarize the kidney structure and functions on the osmoregulations in the Amphibia. Amphibians excrete the water absorbed through their skin as a dilute urine. Pronephros of tadpoles may start to work in the hatching stages and metanephros is well developed and functions. Glomerular filtration rate is relatively large and glomerular intermittency is important to regulate urine production. The proximal tubule reabsorbs approximately 20-45% of filtered water and sodium. Absorption is driven by the basolateral Na+, K(+)-ATPase common to all tubular cells. The diluting segment, early parts of distal nephron, highly develops basolateral interdigitation and reabsorbs approximately 40% of filtered Na+, K+, and Cl-, but is impermeable to water, thus this part results in the formation of hypo-osmotic tubular fluid. In the late distal tubule, the primary mechanism of reabsorption may be via a luminal NaCl synporter, driven by the ubiquitous Na+, K(+)-ATPase on basolateral membrane. In collecting tubule, there are two types of cells, the principal cells and the intercalated cells. Many hormonal and nervous regulations are involved in the glomerular filtration rate and reabsorptions in the amphibian nephrons.

Adaptation, Biological↗
PubMed2000

Genetic analysis of Japanese patients with persistent hyperinsulinemic hypoglycemia of infancy: nucleotide-binding fold-2 mutation impairs cooperative binding of adenine nucleotides to sulfonylurea receptor 1.

To elucidate the genetic etiology of persistent hyperinsulinemic hypoglycemia of infancy (PHHI) in the Japanese population, we conducted a polymerase chain reaction-single-strand conformation polymorphism analysis of the sulfonylurea receptor 1 (SUR1) and Kir6.2 genes in 17 Japanese PHHI patients, including a pair of siblings from a consanguineous family. We also analyzed the glutamate dehydrogenase gene for the exons encoding an allosteric regulatory domain of the enzyme. In the SUR1 gene, we identified one frameshift (I446fsdelT) and two missense (R1420C, R1436Q) mutations. None of these mutations were found in control Japanese subjects. Siblings homozygous for the R1420C mutation had a mild form, whereas two patients heterozygous for the I446fsdelT and R1436Q mutations, respectively, exhibited a severe form of PHHI. Functional consequences of these mutations on K(ATP) function were evaluated using 86Rb+ efflux studies in COS-7 cells. SUR1-446fsdelT and SUR1-1436Q did not form a functional K(ATP). Western blot analysis after transient expression in COS-7 cells revealed the expression of SUR1-1436Q protein to be markedly reduced, suggesting SUR1-1436Q to be unstable in these cells. K(ATP)(SUR1-1420C) showed reduced responses to metabolic inhibition by oligomycin and 2-deoxyglucose. K(ATP) channels are under complex regulation by intracellular ATP and ADP. ATP both inhibits and activates these channels. The inhibition is probably mediated through direct ATP interaction with a pore-forming subunit Kir6.2, whereas the activation is likely to be through a regulatory subunit SUR1. There is a cooperative regulation of ATP and ADP binding to SUR1, and this cooperativity may be involved in regulating the K(ATP) channel. In SUR1-1420C, high-affinity binding of ATP to the nucleotide-binding fold (NBF)-1 was indistinguishable from that of wild-type SUR1. However, stabilization of ATP binding to NBF-1 by MgATP or MgADP was impaired, suggesting that this defect may account for impaired K(ATP)(SUR1-1420C) function. This is the first direct biochemical evidence that the cooperativity of nucleotide binding to SUR1 is impaired in a SUR1 mutant causing PHHI. No mutations were identified in the Kir6.2 and glutamate dehydrogenase genes. The genetic etiology of PHHI appears to be heterogeneous. SUR1 mutations may account for no more than 20% of PHHI cases in Japanese patients. Mutations of Kir6.2 and glutamate dehydrogenase genes are likely to be even less common.

ATP-Binding Cassette Transporters↗
PubMed2000

Long-term follow-up study of unruptured vertebral artery dissection: clinical outcomes and serial angiographic findings.

OBJECT: Although the spontaneous occurrence of an unruptured vertebral artery (VA) dissection has increasingly been recognized as a relatively common cause of stroke, and the clinical aspects of this lesion have gradually been determined, its natural course remains obscure. The main goal of this study was to clarify the management protocol for this condition by examining serial angiographic changes in patients with unruptured VA dissections. METHODS: Seventeen patients with unruptured VA dissections, including 13 men and four women, were clinically and angiographically examined between 1993 and 1998. All patients were observed using serial angiography studies. The initial angiography examinations most frequently revealed stenotic lesions (appearance of a pearl-and-string sign or string sign) in eight (47.1%) of 17 cases. In 15 cases (88.2%), changes in the lesions were evident on follow-up angiography studies. Stenotic lesions resulted in occlusion in four cases, normalization in three, and subsequent formation of an aneurysm in one case, which was treated successfully by proximal occlusion of the affected vessel performed using a detachable balloon. Occluded lesions, which were initially observed in three patients, recanalized in two patients and remained unchanged in one patient. Fusiform dilation alone was demonstrated in three patients during the initial angiography session; these lesions became normalized or were unchanged on follow-up studies. Saccular aneurysms were observed in two patients. In one of these cases, proximal ligation of the parent artery was successfully performed because of subsequent aneurysm enlargement. A double lumen, which appeared in one patient with an extradural VA dissection, became occluded. Magnetic resonance T2-weighted imaging studies revealed infarction corresponding to the posterior circulation in seven cases. During long-term observation in this series, good or excellent recovery was obtained in 14 (87.5%) of 16 patients, and moderate or severe disability in two (12.5%); one patient was lost to follow up after the second angiography study. CONCLUSIONS: A follow-up angiography study must be performed during the early stage (within approximately 3 weeks after onset of symptoms) to confirm the formation or enlargement of an aneurysm, because such conditions may be amenable to surgical treatment. Unruptured VA dissection could otherwise be treated and followed conservatively. Although the majority of dissected lesions seem likely to stabilize within a few months, as evidenced on angiography, in some cases a longer observation period is required.

Adult↗
PubMed2000

Iodinated free fatty acid and 201T1 uptake in chronically hypoperfused myocardium: histologic correlation study.

UNLABELLED: 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) is a tracer for the evaluation of ischemic heart disease. The purpose of this study was to assess the relationship between 1231-BMIPP uptake and myocardial fibrosis. METHODS: Fifteen patients who underwent cardiac surgery were examined by imaging with 201TI and 123I-BMIPP, and histologic specimens were taken during surgery. The relative uptake of 201TI (%TI) and that of 123I-BMIPP (%BMIPP) were calculated. The percentage of fibrosis (%fibrosis) was analyzed with the specimen. RESULTS: %TI correlated strongly with %fibrosis (r = -0.94; P < 0.001). %BMIPP also correlated significantly with %fibrosis (r = -0.88; P < 0.001), but the change in %BMIPP looked biphasic. In the category of only mild fibrosis, %BMIPP showed a steep decrease. 123I-BMIPP-201TI mismatch was found only for fibrosis <20%. CONCLUSION: 123I-BMIPP gave specific information about metabolic changes that occurred in ischemic myocardium without severe fibrotic changes.

Coronary Disease↗
PubMed2000

Detection of complement-fixing antiphospholipid antibodies in association with thrombosis.

Antiphospholipid antibody (aPL) is a hallmark of antiphospholipid syndrome (APS), characterized by thrombosis and recurrent fetal loss. We developed a novel ELISA system to detect complement-fixing ability of anticardiolipin antibody (aCL), and evaluated its clinical usefulness through studying the prevalence of the antibodies in rheumatic diseases, especially in association with thrombosis and recurrent abortion. Among 189 patients with rheumatic diseases, the complement-fixing aCL was positive in 26 (83.9%) of 31 patients with APS and 2 (1.3%) of 158 with other disease categories, whereas it was not positive among 52 normal subjects. Twenty-seven of 28 patients (96.4%), who were positive for complement-fixing aCL, had the episodes or history of thrombosis and/or recurrent abortion, at the time we studied. The remaining one in this group developed APS manifesting pulmonary infarction and occlusion of mesenteric artery 6 months after the evaluation. The sensitivity and specificity of this assay system were 75.0% and 99.3%, respectively, in relation with thrombotic episodes. On the other hand, the IgG aCL were positive in 28 (77.8%) of 36 cases with recent thrombotic episodes and 24 (15.7%) of 153 cases with no recent thrombotic episodes. The sensitivity and specificity of IgG aCL assay system were 77.8% and 84.3%, respectively, in relation with thrombotic episodes. These results indicate that complement-fixing aCL may specifically occur in association with the episodes of thrombosis and/or recurrent abortion in patients with APS compared to IgG-aCL. The method for detecting the complement-fixing aCL is simple, and it provides the useful diagnostic marker for thrombotic manifestations associated with APS.

Antibodies, Antiphospholipid↗
PubMed2000

Combination of inhaled nitric oxide therapy and inverse ratio ventilation in patients with sepsis-associated acute respiratory distress syndrome.

Inverse ratio ventilation (IRV) is a ventilatory technique that uses an inspiratory to expiratory ratio (I:E) greater than 1:1. We studied the effects of mechanical ventilation with an I:E of 1:3, 1:1, and 2:1 on arterial oxygenation in 10 patients with sepsis-associated acute respiratory distress syndrome (ARDS). At each I:E, patients received 0 and 4 ppm of inhaled nitric oxide (INO) in random order for 30 min. Respiratory and cardiovascular parameters were measured. Of the 10 patients studied, 7 responded to IRV and 3 did not. An increase in the I:E and the addition of INO significantly improved arterial oxygenation in the responders (p < 0. 0001 and p < 0.006, respectively). The combination of an increase in the I:E and INO had an additive effect on arterial oxygenation. The combined use of IRV and INO is a more effective method of avoiding hypoxemia than either INO or IRV alone.

Administration, Inhalation↗
PubMed2000

[New therapeutic strategy against colon cancer based on a tumor-specific approach].

To develop a new therapy against colon cancer, we investigated two kinds of strategy using a cancer-specific approach. First, we employed the Cre/loxP regulation system to enhance the specific expression by carcinoembryonic antigen (CEA) promotor in CEA-producing tumor cells, and examined whether sufficient enhancement to transcriptional activity of CEA promotor, which maintains its specificity in vitro and in vivo, could be obtained. Next, using dendritic cells pulsed with HLA-A24 epitope peptides of CEA, we performed a Phase I study of active immunotherapy in patients with advanced colon cancer. These results suggest that the newly developed therapy for colon cancer is a promising strategy; however, minor modification may be necessary.

Antigen-Presenting Cells↗