Biomedical subjects

M Inoue

Publications and source records attributed to M Inoue.

At least 361 records · Page 20Linked to original sources

PubMed2000

Effective percutaneous transhepatic biliary drainage for cystic dilatation of the intrahepatic biliary system in biliary atresia: a case report.

We report on a 16-year old girl with postoperative biliary atresia developing cystic dilatation of the intrahepatic biliary system (CDIB) with abdominal pain, which was relieved after percutaneous transhepatic biliary drainage (PTBD). A cyst was detected in segment 4 of the liver at the age of 14 years. She developed severe right hypochondralgia, subfever and liver dysfunction. Percutaneous cholangiogram showed a solitary cyst without communication and a PTBD tube was placed within the cyst. After lavage of the cyst through PTBD, CDIB was re-communicated with the intestine and the pain was relieved with reduction of the cyst size. From this experience, PTBD may be a less invasive treatment as the first choice for non-communicating CDIB and may alleviate the symptoms when recommunication with the intestine is obtained.

Adolescent↗

PubMed2000

Primary aldosteronism as a cause of severe postpartum hypertension in two women.

Two women who first had the clinical features of primary aldosteronism in the postpartum period are described. Their gestations were virtually uneventful. After delivery, however, progressively severe hypertension (Joint National Committee VI, stage 3) with hypokalemia developed. Pregnancy may conceal the clinical symptoms of primary aldosteronism that causes unexpected severe hypertension in the postpartum period.

Adrenal Gland Neoplasms↗

PubMed2000

Clinical application of malignancy potential grading as a prognostic factor of human esophageal cancers.

BACKGROUND: Various biologic markers have been reported to be prognostic factors in human esophageal cancers. In the current study, we established a new tumor-grading system representing the malignancy potential of cancer cells and compared it with the clinical-stage system. METHODS: Tumor samples from 77 patients with squamous cell carcinoma of the esophagus were immunohistochemically evaluated for the expression of 10 molecules: the cell cycle-related molecules of cyclin D1, Rb, p16INK4, p27KIP1, and PCNA; the cell-cell adhesion molecules of E-cadherin, alpha-catenin, and beta-catenin; and the heat shock proteins of HSP27 and HSP70. RESULTS: P27KIP1, beta-catenin, and HSP70 were selected for their high hazard ratio in multivariate analysis, and the number of their disordered molecules was used to define the malignancy grade (MG). Five-year survival rates were 83%, 54%, 17%, and 0% for MG1, MG2, MG3, and MG4. The gradation of survival curves was better for MGs than for clinical stages. MGs and clinical stages showed significant correlation; however, 55% of those in higher clinical stages (stage 3 or 4) had lower MG (MG1 or 2) and showed better prognosis than others in their group (stage 3 or 4 and MG3 or 4). The proportions of shorter survival span to cancer death patients (less than 1 year) were 0%, 33%, 75%, and 100% in MG1, 2, 3, and 4, but the clinical stage was not associated with the survival span. CONCLUSIONS: The grading of malignancy potential is clinically useful, especially for selecting patients who may show good prognosis in the advanced clinical stage and for predicting short survival span. These predictions are not possible with the clinical-stage system, which is based on the anatomic spread of cancer cells.

Cell Cycle Proteins↗

PubMed2000

Effect of stimulation of the dorsal aspect of the cervical spinal cord on local cerebral blood flow and EEG in the cat.

Currently there is considerable interest in electrical stimulation of the dorsal aspect of the cervical spinal cord as a potentially effective therapy for persistent vegetative patients. The authors assessed change in the local cerebral blood flow (LCBF) and electroencephalogram (EEG) in the cat following spinal cord stimulation (SCS). In 31 adult cats under isoflurane anesthesia, an electrode for SCS was introduced epidurally to the midline of the C2-C3 segment. Stimulation was performed at 25 Hz and 0.1 msec for 30 min. These animals were divided into five groups by the voltage: (1) 2V (n = 7), (2) 4V (n = 7), (3) 6V (n = 7), (4) 4V with intravenous injection of muscarinic cholinergic agents--atropine sulfate (n = 5), and (5) sham-operated control (n = 5) without stimulation. LCBF was measured by laser Doppler flowmetry through bilateral small burr holes at the parietal area during and 60 min after stimulation. At 2V, LCBF increased only during SCS, then returned to the pre-stimulated level, while the increase continued until the end of the experiment at 4V and 6V. The increase in LCBF was not affected by atropine sulfate. EEG showed spike and wave or polyspikes after SCS in two animals of the 6V group, but not in the 2V and 4V groups, and moreover a moderate increase of the background activity at only 4V. The present data suggested that SCS at 4V can provide the appropriate microcirculatory enhancement with less harmful influence which continues to increase 30 min after SCS, although the exact mechanism should be elucidated continuously. Within the limitation of animal experiments, this study could provide the logical basis for determining the condition of SCS.

Acetylcholine↗

PubMed2000

Cross-talk between NO and oxyradicals, a supersystem that regulates energy metabolism and survival of animals.

Mammalian tissues have large amounts of available ATP which are generated by oxidative phosphorylation in mitochondria. For the maintenance of the human body, a large amount of oxygen is required to regenerate these ATP molecules. A small fraction of the inspired oxygen is converted to superoxide radical and related metabolites even under physiological conditions. Most reactive oxygen species react rapidly with a variety of molecules thereby interfering with cellular functions and induce various diseases. Nitric oxide (NO) is an unstable gaseous radical with high affinity for various molecules, such as hemeproteins, thiols, and related radicals. NO easily penetrates through cell membrane/lipid bilayers, forms dissociable complexes with these molecules and modulates cellular metabolism and functions. Because NO has an extremely high affinity for the superoxide radical, the occurrence of the latter might decrease the biological function of NO. Thus, superoxide radicals in and around vascular endothelial cells play critical roles in the pathogenesis of hypertension and vasogenic tissue injury. Because NO also reacts with molecular oxygen, it rapidly loses its biological activity, particularly under ambient atmospheric conditions where the oxygen tension is unphysiologically high. Thus, biological functions of NO are determined by the local concentrations of molecular oxygen and superoxide radicals.

Animals↗

PubMed2000

Concept for organ engineering: a reconstruction method of rat liver for in vitro culture.

In the past decade, there have been remarkable advances in tissue engineering technology toward the goal of creating organoids in vitro from cells and cellular scaffolding. Indeed, tissue-engineered organoids such as skin and cartilage, each with comparatively simple architectures, are presently at the clinical stage. However, conventional tissue engineering techniques have not allowed for the reconstruction of an organoid that mimics an organ of complex architecture of abundant vascular networks. We established a method for organ engineering that can remodel a rat liver into a reconstructed organoid without separating the majority of liver cells by a continuous three-step perfusion. The liver was perfused through its vascular system with a buffered balanced salt solution to cleanse blood from the organ, with a collagenase/dispase medium to deconstruct cellular scaffolds, and with a culture medium containing collagen type I to reorganize the multicellular architecture. The reconstructed organoid was then prepared by excising the perfused liver from the rat and culturing it at 37 degrees C for 2 h. Histologically healthy parenchymal hepatocytes expressing albumin were observed in the excised organoid even after culture for 3 weeks. Furthermore, a fibroblast-implanted organoid was prepared by using a culture medium containing suspended fibroblasts in the third step of the perfusion procedure, demonstrating the efficacy of heterogeneous cells for the reconstruction of an organoid. This method may be applicable to the formation of organoids from other organs, such as kidney and spleen, each of which have abundant capillaries, and therefore the method provides a novel concept for the development of lab-grown organs, i. e., organ engineering.

Animals↗

PubMed2000

Neuronal interactions related to working memory processes in the primate prefrontal cortex revealed by cross-correlation analysis.

To understand neuronal mechanisms for manipulating and/or integrating information in working memory processes, we examined functional interactions among prefrontal neurons exhibiting various task-related activities by cross-correlation analysis. Among 168 neuron pairs isolated, 84 (50%) had significant peaks in cross-correlograms (CCGs); 30 had excitatory central peaks at time 0, 38 had excitatory peaks displaced from time 0, 13 had inhibitory central peaks, and three had both excitatory and inhibitory peaks displaced from time 0. Although significant interactions were observed among prefrontal neurons having various task-related activities, the information flow is present from prefrontal neurons having cue-period activity to neurons having oculomotor activity through neurons having delay-period activity. In addition, neuron pairs both having delay-period activity tended to have significant excitatory peaks in CCGs. Further, neuron pairs that had excitatory central peaks in CCGs tended to have similar directional preferences in task-related activities, and this similarity was the highest in neuron pairs both having cue-period activity. Neuron pairs that had displaced peaks in CCGs also showed similarity in directional preferences in task-related activities, and this similarity was also higher in neuron pairs both having cue-period activity. Interactions between neurons exhibiting task-related activity with different directional preferences increase as the temporal sequence of the task progresses. These results suggest that these interactions play an important role for manipulating and integrating information.

Animals↗

PubMed2000

Comparative analysis of the genomic structures and promoter activities of mouse Siaalpha2,3Galbeta1,3GalNAc GalNAcalpha2, 6-sialyltransferase genes (ST6GalNAc III and IV): characterization of their Sp1 binding sites.

The genomic organization of the genes encoding the mouse N-acetylgalactosamine alpha2,6-sialyltransferase specific for Siaalpha2,3Galbeta1,3GalNAc (ST6GalNAc III and IV) has been determined. The ST6GalNAc III gene spans over 120 kilobases of genomic DNA with 5 exons; on the other hand, the ST6GalNAc IV gene spans over 12 kilobases of genomic DNA with 6 exons. But the exon-intron boundaries of these genes are very similar. The 5'-flanking regions of these genes do not contain a TATA- or CAAT-box but have three putative Sp1 binding sites for each promoter. Transient transfection experiments demonstrated functional promoter activity in an ST6GalNAc III-expressing cell line, P19, for the ST6GalNAc III promoter, and in an ST6GalNAc IV-expressing cell line, NIH3T3, for the ST6GalNAc IV promoter. Mobility shift assaying and mutational analysis of the promoter region indicated that two of the three Sp1 binding sites are involved in the transcriptional regulation of the ST6GalNAc III gene in P19 cells, while all three Sp1 binding sites are involved in the transcriptional regulation of the ST6GalNAc IV gene in NIH3T3 cells.

3T3 Cells↗

PubMed2000

Molecular cloning and genomic analysis of mouse GalNAc alpha2, 6-sialyltransferase (ST6GalNAc I).

cDNA clones encoding mouse GalNAc alpha2,6-sialyltransferase (ST6GalNAc I) were isolated from a mouse submaxillary gland cDNA library. The deduced amino acid sequence of cDNA clones is 526 amino acids in length and has highly conserved motifs among sialyl transferases, sialyl motifs L, S, and VS. The expressed recombinant enzyme exhibited similar substrate specificity to chicken ST6GalNAc I. The mouse ST6GalNAc I gene was expressed in submaxillary gland, mammary gland, colon, and spleen. The mouse ST6GalNAc I gene was also cloned from a mouse genomic library, which was divided into 9 exons spanning over 8 kilobases of genomic DNA. The genomic structure of the mouse ST6GalNAc I gene was similar to that of the mouse ST6GalNAc II gene. Unlike the ST6GalNAc II gene, however, which has a housekeeping gene-like promoter with GC-rich sequences, the ST6GalNAc I gene has two promoters and they do not contain GC-rich sequences but contain putative binding sites for tumor-associated transcription factors such as c-Myb, c-Myc/Max, and c-Ets. Analysis of the 5'-RACE PCR products suggested that the mouse ST6GalNAc I gene expression is regulated by these two promoters in tissue-specific manners.

Amino Acid Sequence↗

PubMed2000

Genomic organization and transcriptional regulation of the mouse GD3 synthase gene (ST8Sia I): comparison of genomic organization of the mouse sialyltransferase genes.

The genomic organization of the gene encoding the mouse GD3 synthase (ST8Sia I) has been determined. The mouse ST8Sia I gene spans over 100 kilobases of genomic DNA with a unique genomic structure of 5 exons. Analysis of the sequence immediately upstream of the transcription initiation site revealed that the ST8Sia I promoter contained no canonical TATA- or CCAAT-box, but contained a putative Sp1 binding site. Transient transfection experiments demonstrated functional promoter activity of the ST8Sia I promoter in an ST8Sia I-expressing cell line, P19, but not in an ST8Sia I-nonexpressing cell line, NIH3T3. Mobility shift assay and mutation analysis of the promoter region indicated that the Sp1 binding site is involved in the transcriptional regulation of the ST8Sia I gene in P19 cells. Here, the genomic structural analyses of mouse sialyltransferase genes are summarized and the genomic structures of these genes are compared.

Animals↗

PubMed2000

Long-term results of lipiodol-transcatheter arterial embolization with cisplatin or doxorubicin for unresectable hepatocellular carcinoma.

The long-term effects of Lipiodol-transcatheter arterial embolization (Lp-TAE) combined with cisplatin (CDDP) or doxorubicin (ADM) on unresectable hepatocellular carcinoma (HCC) were analyzed. Eighty-four consecutive patients with unresectable HCC were treated with TAE. Of the 84, 38 patients were treated with CDDP-Lp-TAE (CDDP group), whereas the remaining 46 patients were treated with ADM-Lp-TAE (ADM group). No significant difference in characteristics of patients and tumors was noted between the groups. CDDP (50 mg) or ADM (20-50 mg) was administered with Lp followed by embolization of the feeding arteries using gelatin sponge particles. The mean number of TAE treatments was 3.3 in the CDDP group and 1.9 in the ADM group (p < 0.01). The 5-year overall survival rates of the CDDP group and the ADM group were 19% and 6%, respectively. The overall survival rate of the CDDP group was significantly higher than that of the ADM group (p < 0.05). No serious side effects were observed in either group. CDDP-Lp-TAE improved the prognosis of unresectable HCC compared with ADM-Lp-TAE, which may be attributable to the fact that CDDP-Lp-TAE treatment could be repeated more times than ADM-Lp-TAE.

Adult↗

PubMed2000

Oxidative stress augments secretion of endothelium-derived relaxing peptides, C-type natriuretic peptide and adrenomedullin.

OBJECTIVE: Excess oxidative stress is one of the major metabolic abnormalities on vascular walls in hypertension and atherosclerosis. In order to further elucidate the endothelial function under oxidative stress, the effect of hydrogen peroxide (H2O2) on expression of two novel endothelium-derived vasorelaxing peptides, C-type natriuretic peptide (CNP) and adrenomedullin (AM) from bovine carotid artery endothelial cells (BCAECs) was examined. METHODS: BCAECs were treated with H2O2 (0.1-1.0 mmol/ l) and/or an antioxidant, N-acetylcysteine (NAC) (5-10 mmol/l), and incubated for 48 h. The concentrations of CNP and AM were measured with the specific radioimmuno assays that we originally developed. CNP and AM mRNA expressions were also examined by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Treatment of BCAECs with 0.5 and 1 mmol/l H2O2 induced 9-and 10-fold increases of CNP concentration in the media. Addition of 10 mmol/l NAC significantly suppressed the effect of H2O2 by 52%. RT-PCR analysis showed that CNP mRNA expression in BCAECs was also rapidly augmented within 1 h with H2O2 (1 mmol/l) treatment, and reached a peak at 3 h to show a 10-fold increase. AM secretion from BCAECs also increased to two-fold with exposure to 0.5 mmol/l H2O2, accompanied with the augmented level of AM mRNA. NAC 10 mmol/l completely suppressed the effect of H2O2 on AM secretion. CONCLUSIONS: In this study, it has been demonstrated that H2O2 augments endothelial secretion of the two endothelium-derived relaxing peptides, CNP and AM. Our findings suggest the increased secretion of CNP and AM from endothelium under oxidative stress may function to compensate the impaired nitric oxide-dependent vasorelaxation in hypertension and atherosclerosis.

Acetylcysteine↗

PubMed2000

Altered gene expression of uncoupling protein-2 and -3 in stroke-prone spontaneously hypertensive rats.

BACKGROUND: Uncoupling proteins (UCPs) are the inner mitochondrial membrane-associated proteins, which dissipate the proton gradient and generate heat instead of ATP. The involvement of UCPs in energy expenditure and glucose metabolism has been suggested. Recently, we succeeded in cloning of rat UCP2 and UCP3. OBJECTIVE: The aim of this study was to elucidate the pathophysiological role of UCP2 and UCP3 in hypertension associated with hyperglycemia in stroke-prone spontaneously hypertensive rats (SHR-SP). METHODS: UCP2 and UCP3 mRNA levels of cardiac and gastrocnemius muscles in SHR-SP and Wistar-Kyoto (WKY) rats were determined at 6 weeks (prehypertensive stage) and at 15 weeks (hypertensive stage). RESULTS: UCP2 and UCP3 mRNA levels in the heart of SHR-SP at 6 weeks were significantly higher than those of WKY rats (1.6-fold, 3.6-fold, respectively). These tendencies did not change in the heart at 15 weeks. UCP2 and UCP3 mRNA levels in the skeletal muscle of SHR-SP at 6 weeks were significantly higher than those of WKY rats (1.4-fold, 2.4-fold, respectively). In contrast, at 15 weeks, UCP2 and UCP3 mRNA levels in the skeletal muscle of SHR-SP were significantly lower than those of WKY rats (70 and 36% of WKY rats, respectively). Therefore, the decrease of UCP2 and UCP3 in the skeletal muscle was observed with the concomitant development of hypertension in SHR-SP. UCP2 mRNA levels in the epididymal fat of SHR-SP at 15 weeks were similar to that of WKY rats. CONCLUSIONS: Altered gene expression of UCP2 and UCP3 might be related to some pathophysiological aspects in hypertension and glucose metabolism in SHR-SP.

Adipose Tissue↗

PubMed2000

Nucleotide sequencing and transcriptional analysis of two tandem genes encoding glucosyltransferase (water-soluble-glucan synthetase) in Streptococcus cricetus HS-6.

Two tandem genes encoding glucosyltransferase synthesizing water-soluble glucan (GTF-S) were cloned from the lambda gene library of Streptococcus cricetus HS-6 (serotype a) using anti-GTF-S antibody, and the nucleotide sequences were analyzed. The two genes (ORF1 and ORF2) were identified as streptococcal glucosyltransferases based on the following evidence: [1] the deduced amino acid sequences of their products have an active site for catalytic action and C-terminal repeated units for dextran binding, and [2] a homology search revealed that the ORF1 and ORF2 products are homologous to the GtfS protein (77.4%) of S. downei Mfe28 and GtfT protein (83.8%) of S. sobrinus OMZ176, respectively, which are both known to have GTF-S activity. Therefore, ORF1 and ORF2 might be designated gtfS and gtfT of S. cricetus, respectively. A Northern blotting and RNase protection assay suggested that the gtfS and gtfT of S. cricetus are transcribed as a single bicistronic mRNA as well as separate monocistronic mRNAs. Primer extension analysis indicated multiple transcriptional start points for each gene.

Amino Acid Sequence↗

PubMed2000

Serological properties of Abiotrophia and Granulicatella species (nutritionally variant streptococci).

Serological variations were examined among 12 type or reference strains and 91 oral isolates of vitamin B6-dependent Abiotrophia and Granulicatella spp. Rabbits were immunized with whole cells of 12 selected strains and 10 typing antisera were obtained, which were unreactive with the Lancefield group A to G antigen preparations. The reactivity of the antisera and autoclaved cell surface antigen extracts was tested by double diffusion in agar gel and a capillary precipitin test. These typing antisera categorized all Abiotrophia defectiva strains, all except one Granulicatella elegans strain, three-quarters of the Granulicatella adiacens, and half of the Granulicatella paraadiacens into 8 serotypes and 2 subserotypes. The Granulicatella balaenopterae type strain was unserotypable. All A. defectiva strains were serotype I, some of which were divided into subserotype I-1 and/or I-5. The G. adiacens strains generally belonged to serotype II or III, and the G. paraadiacens strains to serotype IV, V or VI. All G. adiacens or G. paraadiacens serotype II strains were also subserotype I-5. The G. elegans strains were serotype VII or VIII. These Abiotrophia and Granulicatella serotypes were undetectable among 33 strains of the other 11 species including the bacteriolytic enzyme-producing but vitamin B6-independent strains of Streptococcus, Enterococcus, Dolosigranulum and Aerococcus. The proposed serotyping system for Abiotrophia and Granulicatella spp. would be helpful in the identification and classification of these unique coccal isolates in ecological and epidemiological studies.

Animals↗

PubMed2000

More frequent beta-catenin gene mutations in adenomas than in aberrant crypt foci or adenocarcinomas in the large intestines of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-treated rats.

Alteration of adenomatous polyposis coli (APC) is known to be an early event in neoplasia, causing activation of the beta-catenin / Tcf pathway. Although it is thought that alterations in APC and beta- catenin may complement one another, the contribution of beta-catenin mutations to colorectal carcinogenesis remains unclear. We therefore performed PCR-single strand conformation polymorphism analysis and direct sequencing of exon 3 of beta-catenin gene in adenomas, adenocarcinomas, and aberrant crypt foci (ACF), considered to be putative precursor lesions of colorectal neoplasias, in 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) treated F344 rats. beta-Catenin mutations were identified in all of 7 adenomas (100%) and 6 of 12 (50%) adenocarcinomas. All of the mutations were found in codons 32 through 34, the serine encoded by codon 33 being an important phosphorylation site by glycogen synthase kinase-3beta. Regarding ACF, 14 of 46 (30.4%) were found to be mutated, eleven (78%) in codon 34, and the others in codon 45 (frequently altered in human colon cancer), and codons 47 and 56 (which have not been previously reported). The frequency of beta-catenin mutations in adenomas was significantly higher than in ACF (P < 0.001) and adenocarcinomas (P < 0.05). Thus, beta-catenin mutations may have more importance in the genesis of adenomas than ACF or adenocarcinomas in rat colon carcinogens by PhIP.

Adenocarcinoma↗

PubMed2000

Endocardiac infectivity and binding to extracellular matrix proteins of oral Abiotrophia species.

Microorganisms of the genus Abiotrophia, formerly known as nutritionally variant streptococci, are members of the oral flora and often isolated from patients with endocarditis, but pathogenicity of oral Abiotrophia species has not been examined yet. In this study, 17 strains isolated from healthy human oral cavities and 7 reference strains (all derived from patients with endocarditis) of Abiotrophia spp. were tested for their abilities to cause infections in damaged heart tissues in catheterized rats and to adhere to extracellular matrix proteins in vitro. The reference strains of A. defectiva and A. adiacens showed high infectivities in the rats. Four oral isolates of these two species showed similarly high infectivities and three had moderate infectivities. Most of 10 oral strains of A. para-adiacens and A. elegans were found to be generally less infective. The highly infective A. adiacens strains showed markedly high fibronectin-binding capacity, suggesting a possible relationship between the fibronectin-binding capacity and damaged heart tissue infectivity of the Abiotrophia species. A. defectiva strains which were also highly infective had moderate levels of binding to fibronectin and other extracellular matrix proteins. Most of A. para-adiacens and A. elegans strains showed low or negligible binding capacities to any extracellular matrix proteins tested.

Animals↗

PubMed2000

[Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyo University Hospital--the second report].

We studied the high-level resistant to cefotaxime (CTX, MIC > or = 512 micrograms/ml) clinical isolates of Escherichia coli and Klebsiella pneumoniae in Teikyo University Hospital. The CTX-resistance could be transferred to E. coli K-12 chi 1037 or ML4903 strains from 30 of the 33 isolates by conjugation at a frequency of 10(-4). When the hydrolysis rate of benzylpenicillin was 100%, the beta-lactamases which were extracted from the transconjugants hydrolyzed CTX, CAZ and AZT at the rate of 38-95%, 0-8.6% and 0-56%, respectively. These results demonstrate that these enzymes should be categorized into ESBL. The nucleotide sequence of CTX-resistant gene was identified to that of the CTX-M2 gene which was first described in Argentina. It was found to have 99.9% homology to Toho-1 gene in Japan and 99.6% homology to CMY-2 gene. Using a PCR methods for the detection of one of ESBL gene such as CTX-M2, Toho-1 or CMY-2, the DNA was amplified from all strains (11 isolates of E. coli and 21 isolates of K. pneumoniae).

Cefotaxime↗