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M Ueda

Publications and source records attributed to M Ueda.

At least 577 records · Page 32Linked to original sources
PubMed1997

Pancreatic lymph nodal and plexus micrometastases detected by enriched polymerase chain reaction and nonradioisotopic single-strand conformation polymorphism analysis: a new predictive factor for recurrent pancreatic carcinoma.

K-ras point mutations have been observed in approximately 90% of pancreatic carcinomas. We genetically analyzed cases of pancreatic regional lymph nodal and plexus micrometastases in invasive ductal carcinoma of the pancreas who were node negative or had metastases limited histopathologically to pancreaticoduodenal lymph nodes. These cases underwent curative resection in our institute. The utility of genetic analysis was compared with that of histopathological study, in terms of postoperative clinical outcome, as a predictive factor for recurrent pancreatic carcinoma. Samples for DNA extraction were obtained from formalin-fixed, paraffin-embedded specimens. A 0.5-microg quantity of DNA was subjected to enriched PCR and nonradioisotopic single-strand conformation polymorphism analysis. K-ras codon 12 mutations were detected in 83% (10 of 12) of invasive ductal carcinomas. In four cases, the genetic analysis of regional lymph nodal metastases and pancreatic plexus invasion of the pancreatic carcinoma yielded results concordant with those of histopathological analysis. In six cases, however, the metastases detected by genetic analysis were more advanced than was indicated by the histopathological examination. The survival rate of cases with metastases beyond the pancreaticoduodenal lymph nodes was significantly lower than that of cases with metastases limited to the pancreaticoduodenal lymph nodes or with no nodal involvement based on genetic analysis (P < 0.05). Intraoperative analysis of point mutations at K-ras codon 12 in the regional lymph nodes and the pancreatic plexus by enriched PCR/nonradioisotopic single-strand conformation polymorphism analysis is a highly accurate predictive factor for recurrent pancreatic carcinoma.

Adult↗
PubMed1997

Altered p16/MTS1/CDKN2 and cyclin D1/PRAD-1 gene expression is associated with the prognosis of squamous cell carcinoma of the esophagus.

The p16/MTS1/CDKN2 gene and the cyclin D1/PRAD-1 gene cooperatively regulate cyclin-dependent kinase 4-mediated phosphorylation of pRB in the cell cycle of normal cells. p16/CDKN2 gene and cyclin D1/PRAD-1 gene alterations have been detected in squamous cell carcinoma cell lines and in several primary squamous cell carcinomas of the esophagus. We immunohistochemically assessed p16 and cyclin D1 expression in 111 squamous cell carcinomas of the esophagus after evaluation of the antibodies against p16 and cyclin D1 protein using four squamous cell carcinoma cell lines. Loss of p16 expression was detected in 56 of 111 cases (50%). The mean number of metastatic lymph nodes without p16 expression was significantly higher than the number of nodes with p16 expression (P = 0.04). The postoperative survival rate for patients without p16 expression was significantly lower than that of patients with p16 expression (P = 0.04). Cyclin D1 overexpression was found in 28 of the 111 cases (25%) and correlated with distant organ metastasis after curative surgery (P = 0.05). The survival rate of patients with cyclin D1 overexpression was significantly lower than that of patients without cyclin D1 overexpression (P = 0.01). A positive correlation between the loss of p16 expression and cyclin D1 overexpression was observed (P = 0. 03). The loss of p16 expression and overexpression of cyclin D1 may be useful prognostic indicators in patients with squamous cell carcinomas of the esophagus. It may be possible to select more suitable treatment for patients with squamous cell carcinomas of the esophagus by evaluating the status of p16 and cyclin D1 expression.

Adult↗
PubMed1996

C-type natriuretic peptide in human coronary atherosclerotic lesions.

BACKGROUND: C-type natriuretic peptide (CNP) belongs to the natriuretic peptide family and is considered to have regulatory effects on vascular tone and smooth muscle growth. Since these features play a role in atherogenesis, the presence of CNP at such sites was studied. METHODS AND RESULTS: Thirty-three coronary artery segments were harvested at autopsy: 10 normal, with diffuse intimal thickening, and 23 atherosclerotic lesions. Samples were snap-frozen and processed for immunohistochemical staining. For the identification of CNP, a mouse monoclonal antibody (KY-CNP-1) was used. 1A4, EBM-11 (CD68), and von Willebrand factor antibodies were used to stain smooth muscle cells, macrophages, and endothelial cells, respectively. CNP is present in several cell types. Normal arterial segments show CNP-positive endothelial cells. Hypercellular atherosclerotic lesions show distinct CNP positivity of smooth muscle cells and macrophages but a decrease in positivity of endothelial cells. Advanced atherosclerotic lesions contain CNP-positive macrophages, but the smooth muscle cells within the fibrous cap and the surface endothelial cells are almost all CNP-negative. CONCLUSIONS: These observations suggest that CNP has functional significance in atherogenesis.

Adolescent↗
PubMed1996

Monoclonal antibody, KK1, recognizes human retinal astrocytes and distinguishes a subtype of astrocytes in mouse brain.

Astrocytes exhibit a diverse morphology and numerous functions in the central nervous system as well as in the retina. In order to obtain markers for the analysis of astrocytes, we prepared monoclonal antibodies that recognized antigens specific to astrocytes. Monoclonal antibody (mAb), designated KK1, reacted with the processes of astrocytes in the nerve fiber layer and the ganglion cell layer in the human retina as detected by indirect immunofluorescence. Normal Müller cells, whose processes are localized vertically in retina, were not labeled by KK1 mAb. In mouse brain, KK1 mAb reacted specifically with astrocytes in the white matter, but not with those in the gray matter. Studies employing a high-resolution confocal laser scanning microscope and double-labeling with KK1 mAb and commercially available anti-glial fibrillary acidic protein (GFAP) mAb (GA5) revealed that KK1 mAb visualized the processes that were not recognized by anti-GFAP mAb (GA5) in both human retina and mouse brain. In cultured mouse astrocytes, KK1 mAb reacted only with anti-GFAP mAb (GA5)-positive cells, but a small percentage of anti-GFAP mAb (GA5)-positive cells were labeled with KK1 mAb. In addition, the subcellular distribution of the KK1 antigen in cultured astrocytes apparently differed from that of GFAP labeled by anti-GFAP mAb (GA5). The antigen that was purified from the normal mouse brain by KK1 mAb-conjugated beads reacted with anti-GFAP mAb(GA5) in immunoblotting. No reactivity of KK1 mAb was observed in immunohistochemical analysis in GFAP -/- mutant mouse brain. These results demonstrate that KK1 mAb specifically recognized an epitope of GFAP that did not react with other anti-GFAP mAb (GA5). Retinal astrocytes and a subtype of astrocytes in the white matter of mouse brain shared the epitope that was recognized by KK1 mAb. KK1 mAb might be a powerful tool to investigate a subtype of astrocytes.

Animals↗
PubMed1996

Effects of Euro-Collins, University of Wisconsin, and new extracellular-type trehalase-containing Kyoto solutions in an ex vivo rat lung preservation model.

BACKGROUND: We have previously reported the effects of trehalose-based extracellular-type Kyoto (ET-K) solution in lung preservation. Now, we have developed a new ET-K solution by adding three substances--N-acetyl cysteine, dibutyryl cyclic AMP, and nitroglycerin, to ET-K solution. We studied the effects of new ET-K solution in lung preservation, and compare it with Euro-Collins (EC) and University of Wisconsin (UW) solutions using an ex vivo rat reperfusion model. METHODS: The perfusion circuit was initiated by 30 ml of fresh mixed venous blood obtained from three haparinized rats. By means of a double-head roller pump, the blood passed from the venous blood reservoir through the pulmonary artery to be perfused in the examined lung. The lung effluent was returned at the same flow rate to the deoxygenator fresh lung. Four experimental groups were allocated. In group 1 (fresh group, n=6), lung was flushed with saline and reperfused immediately. In the other groups (group 2: new ET-K group, n=6; group 3: UW group, n=6; and group 4: EC group, n=6), lung was flushed with the new ET-K and prostanglandin E1 (PGE1), UW and PGE1, and EC and PGE1, respectively. After 17-hr preservation, the preserved lung was reperfused. RESULTS: In all six animals of the EC group, ventilation of the experimental lung was discontinued at 20 min after reperfusion because of the exudate in the endotracheal tube that resulted from pulmonary edema. The shunt fraction, pulmonary arterial pressure, and peak inspiratory pressure in the new ET-K and UW groups were significantly better than those in the EC group, but were almost equal to those in the fresh group. CONCLUSION: The postpreservation pulmonary functions with the new ET-K solution were better than those with the EC solution, and were equal to those with the UW solution. This new solution is expected to contribute to the increase in donor lungs for clinical lung transplantation. In addition, this ex vivo rat reperfusion model is simple and highly reliable, and can be widely used in the studies of pulmonary preservation.

Adenosine↗
PubMed1996

Generation of CD1+RelB+ dendritic cells and tartrate-resistant acid phosphatase-positive osteoclast-like multinucleated giant cells from human monocytes.

We previously showed that granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF) stimulate the differentiation of human monocytes into two phenotypically distinct types of macrophages. However, in vivo, not only CSF but also many other cytokines are produced under various conditions. Those cytokines may modulate the differentiation of monocytes by CSFs. In the present study, we showed that CD14+ adherent human monocytes can differentiate into CD1+relB+ dendritic cells (DC) by the combination of GM-CSF plus interleukin-4 (IL-4) and that they differentiate into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like multinucleated giant cells (MGC) by the combination of M-CSF plus IL-4. However, the monocyte-derived DC were not terminally differentiated cells; they could still convert to macrophages in response to M-CSF. Tumor necrosis factor-alpha (TNF-alpha) stimulated the terminal differentiation of the DC by downregulating the expression of the M-CSF receptor, cfms mRNA, and aborting the potential to convert to macrophages. In contrast to IL-4, interferon-gamma (IFN-gamma) had no demonstrable effect on the differentiation of monocytes. Rather, IFN-gamma antagonized the effect of IL-4 and suppressed the DC and MGC formation induced by GM-CSF + IL-4 and M-CSF + IL-4, respectively. Taken together, these results provide a new aspect to our knowledge of monocyte differentiation and provide evidence that human monocytes are flexible in their differentiation potential and are precursors not only of macrophages but also of CD1+relB+DC and TRAP-positive MGC. Such a diverse pathway of monocyte differentiation may constitute one of the basic mechanisms of immune regulation.

Acid Phosphatase↗
PubMed1996

Cloning and sequencing of the cDNA encoding beta-glucosidase 1 from Aspergillus aculeatus.

A cDNA was isolated from an Aspergillus aculeatus cDNA library using synthetic oligodeoxyribonucleotide mixtures that corresponded to the internal amino acid (aa) sequence of mature beta-glucosidase 1 (BGL1). Analysis of the nucleotide sequence of the cloned cDNA insert revealed a 2580-bp open reading frame (ORF) that encoded a 860-aa protein. The deduced aa sequence of the ORF shared sequence similarity with several BGL from other microorganisms.

Amino Acid Sequence↗
PubMed1996

Peroxisomal and mitochondrial carnitine acetyltransferases of the n-alkane-assimilating yeast Candida Tropicalis. Analysis of gene structure and translation products.

A genomic DNA clone encoding carnitine acetyltransferases (EC 2.3.1.7), localized in two subcellular organelles, peroxisomes and mitochondria of an n-alkane-assimilating yeast Candida tropicalis, was isolated from the yeast lambda EMBL library using a carnitine acetyltransferase CDNA probe. Nucleotide sequence analysis disclosed that the open reading frame was 1881 bp, corresponding to 627 amino acids with a molecular mass of 70760 Da. Comparison of the predicted amino acid sequence of the C. tropicalis enzyme with that of Saccharomyces cerevisiae mitochondrial matrix carnitine acetyltransferase revealed 46.3% identity. It was noticeable that the C. tropicalis enzymes had amino acid sequences similar to both proposed mitochondrial and peroxisomal targeting signals. When the C. tropicalis gene was expressed in S. cerevisiae using its own 5'-upstream region, a 12-fold increase in activity was observed. Western blot analysis revealed the presence of two major proteins whose sizes corresponded to the peroxisomal and mitochondrial proteins detected in C. tropicalis. This suggested that peroxisomal and mitochondrial carnitine acetyltransferases were encoded by one gene, as suggested for the S. cerevisiae enzyme. Furthermore, we have separated and purified these enzymes from peroxisomes and mitochondria of C. tropicalis, and analyzed the amino-terminal amino acid sequences of each. The amino-terminal sequence of the mitochondrial enzyme suggested that a signal sequence had been cleaved during translocation into mitochondria. Concerning the peroxisomal enzyme, the evidence obtained indicated that in vivo the translation was initiated at the second methionine of the open reading frame.

Alkanes↗
PubMed1996

Cloning of a cluster of chitinase genes from Aeromonas sp. No. 10S-24.

A gene encoding chitinases from Aeromonas sp. No. 10S-24 was cloned into Escherichia coli DH5 alpha using pUC19, and its nucleotides were sequenced. The chitinase gene was clustered in ORFs (open reading frame) 1 to 4, in a 8-kb fragment of DNA. ORF-1 consisted of 1608 bp encoding 535 amino acid residues, and ORF-2 consisted of 1425 bp encoding 474 amino acid residues. ORF-3 was 1617 bp long and encodes a protein consisting of 538 amino acids. ORF-4 encodes 287 amino acids of the N-terminal region. The amino acid sequences of ORF-1 and ORF-3 share sequence homology with chitinase D from Bacillus circulans, and chitinase A and B from Streptomyces lividans. The amino acid sequence of ORF-2 shared sequence homology with chitinase II from Aeromonas sp. No. 10S-24, and chitinase from Saccharopolyspora erythraea. A region of the sequence starting from Ala-28 of the amino acid sequence of ORF-3 coincided with the N-terminal amino acid sequence of chitinase III from Aeromonas sp. No. 10S-24.

Aeromonas↗
PubMed1996

Experimental and clinical studies on balloon laserthermia using Nd: YAG laser for uterine endometrial cancer.

BACKGROUND AND OBJECTIVE: No conservative therapy for endometrial cancer exists. We therefore evaluated the new balloon laserthermia for such cases. STUDY DESIGN/MATERIAL AND METHODS: Experimental and clinical study. We examined experimentally porcine kidney and stomach, human resected uterus and clinically on 12 patients with endometrial cancer and two patients with hyperplasia. RESULTS: Temperatures were safely kept at the balloon surface. Laser irradiation should be performed for at least 10-15 min, 65-70 degrees C to produce a suitable degeneration, experimentally. Clinically, necrosis and degeneration to a depth of 4-6 mm was histologically observed. Eight patients with carcinoma and hyperplasia for which laserthermia was effective showed that the surface of cancer was smooth and the depth of invasion was in most cases up to 1/4 of muscle layer. CONCLUSION: Balloon laserthermia may be effective in early endometrial cancer or precancerous lesions. Its clinical usefulness should be investigated further.

Adult↗
PubMed1996

Transgene expression in mammary glands of newborn rats.

Transgene expression in the mammary glands of newborn rats was studied to establish an early selection system for transgenic animals producing exogenous proteins in their milk during lactation. A fusion gene composed of the bovine alpha S1 casein gene promoter and the human growth hormone gene was microinjected into rat embryos. Transgenic lines that produced human growth hormone in their milk were established and used in this study. Immediately after birth, and without any hormone treatment, human growth hormone was found in the extracts of mammary glands from both male and female rats derived from the line secreting human growth hormone in their milk. The expression of the transgene in mammary glands of newborn rats was also detected by the presence of human growth hormone mRNA. Nontransgenic newborn rats did not express the human growth hormone gene in their mammary glands, while the mRNA for rat alpha casein, an endogenous milk protein, was found in all mammary glands from both transgenic and nontransgenic neonates. These results show that analyzing the expression of transgenes in the mammary glands of neonates is a valuable tool to select the desired transgenic animals and to shorten the selection schedules establishing the transgenic animals.

Animals↗
PubMed1996

Overexpression of c-myc induces apoptosis at the prophase of meiosis of rat primary spermatocytes.

Transgenic rats expressing the rat c-myc gene under the control of the human metallothionein II A promoter were produced. We found that the female transgenic rats were fertile, but that the male transgenic rats were sterile. Atrophy of the seminiferous tubules and depletion of sperm were observed in the sterile male testes. The expression of differential stage-specific mRNAs, including those of the c-kit receptor proto-oncogene, meiotic heat-shock protein 70 gene, acrosin gene, and transition protein 1 gene, was analyzed by the reverse transcriptase-polymerase chain reaction during spermatogenesis. The results suggested that spermatogenesis in these sterile rats were arrested at the prophase of meiosis in the primary spermatocytes. We found that apoptotic DNA fragmentation occurred in primary spermatocytes of the sterile transgenic rats. These results suggest that overexpression of the c-myc gene induces apoptosis at the prophase meiosis of the primary spermatocytes thereby causing male sterility in the c-myc transgenic rats.

Animals↗
PubMed1996

A pelvic retroperitoneal schwannoma arising in the right paracolpium.

Nerve sheath tumors of the retroperitoneum are infrequently reported. In this paper, a rare case of a benign pelvic retroperitoneal schwannoma arising in the right paracolpium is presented. Preoperatively, magnetic resonance imaging revealed a solid tumor beside the vaginal canal with a clear margin. The tumor could be completely resected by the transvaginal approach and was diagnosed to be a benign schwannoma of the Antoni A type with palisade arrangement. The patient had no symptoms of motor or sensory disturbances after surgery.

Adult↗