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M Kondo

Publications and source records attributed to M Kondo.

At least 487 records · Page 27Linked to original sources
PubMed1996

Do cold agglutinins have any impact on the outcome of liver transplantation?

Cold agglutinins, IgM red blood cell autoantibodies, cause cold agglutinin disease with hemolysis and microvascular occlusion. Cold preservation of kidneys during renal transplantation in the presence of cold agglutinins can cause graft malfunction. However, the impact of cold agglutinins on the outcome of liver transplantation is unknown. We measured the pretransplant presence and titer of cold agglutinins in 327 primary liver allograft recipients and analyzed their relationship to outcome after transplant. Thirty-three percent of pretransplant patients had cold agglutinins. Cold agglutinins were more common in patients with viral-related liver diseases (49%) compared with those with nonviral-related liver disease (32%). There was no difference between recipients with and without cold agglutinins in usage of blood products, postoperative day 2 aminotransferase levels, acute rejection at day 7, the development of hepatic artery thrombosis, nonanastomotic biliary strictures, or 4-month allograft survival. In conclusion, cold agglutinins are common in liver transplant patients before surgery, especially those with viral-related liver diseases. However, the presence of cold agglutinins does not impact on outcome after liver transplantation.

Agglutinins↗
PubMed1996

Molecular analysis of the FHIT gene at 3p14.2 in lung cancer cell lines.

Chromosome 3p is frequently deleted in various cancers including examples in the lung. A novel gene, termed FHIT, was recently isolated from the fragile site at 3p14.2, with aberrant transcripts being reported in lung cancer tumor specimens. To avoid overlooking tumor-specific altered transcripts due to contaminating normal cells in primary tumors, FHIT alterations were examined in 41 lung cancer cell lines in the present study. Lack of detectable expression or exclusive expression of aberrantly spliced transcripts, often accompanied by intragenic homozygous deletions, were observed in 7 of 24 non-small cell lung cancers (29%) but in 0 of 17 small cell lung cancers (0%). Extensive reverse transcription-PCR-single-strand conformation polymorphism analysis revealed polymorphisms and alternative splicing but failed to identify point mutations. These results suggest distinct mechanisms for FHIT alterations in lung tumorigenesis and that further studies of this interesting gene are warranted.

Acid Anhydride Hydrolases↗
PubMed1996

Somatic in vivo alterations of the JV18-1 gene at 18q21 in human lung cancers.

The chromosome region 18q21 is frequently deleted in lung cancers. Recent identification of JV18-1 at this locus led us to examine whether or not it might also be altered in lung cancers, as is the case for the closely related DPC4 tumor suppressor gene. A missense somatic mutation and a 9-bp in-frame deletion were detected in the highly conserved region of JV18-1 among 57 lung cancer specimens taken directly from patients. The total alterations in JV18-1 and DPC4, however, are not sufficient to account for all 18q21 deletions in lung cancers. These findings suggest that although JV18-1 and DPC4 may play roles in a limited fraction of lung cancers, another tumor suppressor gene may also exist in this chromosome region.

Carcinoma, Non-Small-Cell Lung↗
PubMed1996

Yeast expression of the cytokine receptor domain of the soluble interleukin-6 receptor.

The complex of the soluble interleukin-6 receptor (sIL-6R) and IL-6 (IL-6) is a potent agonist on cells expressing the signal transducing protein gp 130. In contrast, IL-6 alone only stimulates cells which express a membrane bound form of the IL-6R and gp 130. The natural occurring sIL-6R is generated by shedding of the membrane receptor and to a lesser extend by alternative splicing. We have inserted the coding sequence of the 323 amino acid residues of the human sIL-6R into an expression/secretion vector suitable for the methylotrophic yeast Pichia pastoris. We obtained, however, no detectable expression and secretion of the recombinant protein. When we used only the coding sequence of the cytokine receptor domain of the sIL-6R for the construction of an expression plasmid, this truncated version of the sIL-6R accumulated in the supernatant to 1-5 mg/l. The protein was purified by a single affinity chromatography step using a monoclonal antibody directed against the human IL-6R. Following the same approach, we expressed a truncated splice variant of the sIL-6R. Both, the secreted truncated sIL-6R and the splice variant showed full agonistic biological activity on human hepatoma cells. The described expression strategy will be useful for large scale production of biologically active sIL-6R and might be adapted for the expression of other members of the hematopoietic cytokine receptor family.

Antigens, CD↗
PubMed1996

Prevention of adoptively transferred diabetes in nonobese diabetic mice with IL-10-transduced islet-specific Th1 lymphocytes. A gene therapy model for autoimmune diabetes.

Four pancreatic islet-specific CD4+ helper T (Th) 1 (Th1) clones and two Th1 clones transduced with an SRalpha promoter-linked murine IL-10 (mIL-10) cDNA of 2.0-6.0 x 10(6) cells were adoptively transferred to nonobese diabetic (NOD) mice at age 8 d. Cyclophosphamide (CY) was administered at age 37 d (plus CY), and the incidence of diabetes and the histological grade of insulitis were examined at age 47 d. After the adoptive transfer of IL-10-transduced Th1 cells, polymerase chain reaction (PCR) and reverse-transcription (RT)-PCR detected the neo gene and the retrovirus vector-mediated IL-10 mRNA in situ in recipient islets, respectively. RT-PCR detected the decrease of IFN-gamma mRNA relative to IL-10 mRNA in IL-10-transduced Th1 clones in vitro and also in recipient islets. All four wild type Th1 clones plus CY induced the insulitis grade of 2.75 and diabetes in 66% of recipient NOD mice. IL-10-transduced two Th1 clones plus CY induced periinsulitis with the grade of 1.43 and diabetes in 8.0%. The 1:1 mixture of wild type Th1 cells and IL-10-transduced Th1 cells plus CY induced periinsulitis with the grade of 1.85 and diabetes in 20%. The suppression of diabetes through decreasing IFN-gamma mRNA by the tissue-specific delivery of IL-10 to pancreatic islets with IL-10-transduced Th1 cells affords us the starting basis to develop the gene therapy for autoimmune diabetes.

Adoptive Transfer↗
PubMed1996

cDNA cloning and its pronephros-specific expression of the Wilms' tumor suppressor gene, WT1, from Xenopus laevis.

The Wilms' tumor suppressor gene, WT1, plays a crucial role during early urogenital development in mammals. To elucidate the function of WT1 in other vertebrates, we isolated the Xenopus WT1 homolog (XeWT1) from a testis cDNA library. Comparison of the XeWT1 protein with other WT1 proteins revealed that the zinc finger domain of XeWT1 is identical to that of the human WT1 except for the first two amino acid residues. An alternative splice II site, located between the third and the fourth zinc finger is also conserved. In the transcriptional regulatory region, however, three domains, a glycine stretch, a proline stretch and one alternative splice site which are present in the mammalian WT1, are not conserved in amphibians. The XeWT1 gene is expressed in testis and kidney, and whole mount in situ hybridization revealed that the onset of the WT1 gene expression coincides with the early stages of pronephros development in Xenopus. These findings implicate the involvement of WT1 protein during urogenital development in amphibians as well as in mammals.

Amino Acid Sequence↗
PubMed1996

Formation of crossline as a fluorescent advanced glycation end product in vitro and in vivo.

Crossline is one of the major advanced glycation end products resulting the reaction mixture of free amino group(s) such as epsilon-one in lysine with D-glucose in vitro. To study crossline formation on proteins in vitro and in vivo, polyclonal antiserum to the crossline hapten was prepared. This antiserum reacted with bovine and human serum albumin that had been modified by prolonged incubation with glucose as well as with crossline itself. Antisera did not react with unmodified serum albumin or the other Maillard-related compounds. Crossline was formed in a time-dependent manner when a mixture of six different proteins was incubated with glucose at pH 7.2 or 9.0. Crossline levels could be measured in rat lens proteins and the levels increased with age. The crossline content of lens proteins in diabetic rats was more than two-fold higher than that of age-matched controls. Results of this study suggest that most proteins containing advanced glycation end products have crossline-like structures. Measurement of crossline-like structures in biological specimens may provide an index of aging and of the development of diabetic complications.

Animals↗
PubMed1996

Comparison of hypervariable regions (HVR1 and HVR2) in positive- and negative-stranded hepatitis C virus RNA in cancerous and non-cancerous liver tissue, peripheral blood mononuclear cells and serum from a patient with hepatocellular carcinoma.

Hepatitis C virus (HCV) infection is associated with a wide spectrum of liver diseases including cirrhosis and hepatocellular carcinoma (HCC). Although the biological relation between the virus and cirrhosis or HCC is unclear, such variable pathogenicity may be related to the genetic heterogeneity of HCV. Genetic variability of HCV was assessed by determining the nucleotide sequence corresponding to the hypervariable regions (HVR1 and HVR2) of the putative envelope protein (E2/NS1) in positive- and negative-stranded HCV RNA from the cancerous and surrounding non-cancerous liver tissue, peripheral blood mononuclear cells and serum of a patient with HCC. Nineteen distinct HVR1 amino acid sequences (deduced from the nucleotide sequences) were obtained from the patient and could be classified into 5 groups on the basis of the site and time of detection. Some viral isolates with the same HVR1 sequence were shown to replicate in both cancerous and non-cancerous liver tissue, whereas others replicated in HCC tissue only.

Amino Acid Sequence↗
PubMed1996

Requirement of cell interactions through adhesion molecules in the early phase of T cell development.

We investigated the role of adhesion molecules in T cell development. A large proportion of murine fetal thymus (FT) cells obtained at Day 13 of gestation, which are c-kit+, express the adhesion molecules Pgp-1, VLA-4, LFA-1, and ICAM-1 on their surface at high levels. The expression profiles of these adhesion molecules resemble quite well those on c-kit+ cells in fetal liver (FL). The level of expression of these molecules on FT cells declines with the embryonal age and becomes mostly negative by birth except for LFA-1. In the case of LFA-1, a reincrease of expression levels is seen in newborn mice. The role of these adhesion molecules in T cell development was investigated by adding monoclonal antibodies (mAb) into the FT organ cultures, where T cell development from FT or FL progenitors was induced by coculturing these cells with a deoxyguanosine-treated FT lobe. We found that anti-Pgp-1, anti-LFA-1, and anti-VLA-4 mAb severely inhibited the early phase of T cell development from FL progenitors. On the other hand, the suppressive effect of these mAb on the T cell development from FT progenitors was only slight, if any. These findings strongly suggest that interactions with elements in the thymic microenvironment through Pgp-1, LFA-1, and VLA-4 are indispensable for prethymic progenitors to develop into T cells.

Animals↗
PubMed1996

Entire hemithorax irradiation following complete resection in patients with stage II-III invasive thymoma.

PURPOSE: To evaluate the feasibility and efficacy of prophylactic entire hemithorax irradiation (EH) in addition to mediastinal irradiation (MRT) following a complete resection in Stage II-III invasive thymoma. METHODS AND MATERIALS: Forty-three patients with invasive thymoma treated with surgery and radiation therapy between 1978 and 1993 were analyzed retrospectively. All 43 patients underwent a complete surgical resection and were judged to have Masaoka's Stage II-III invasive thymoma. Of these, 23 patients received EH and MRT (EH-MRT) and the remaining 20 received MRT. Of the 23 patients with EH-MRT, 11 were Stage II and 12 Stage III. Of the 20 with MRT, 11 were Stage II and 9 Stage III. In most cases, EH was 15 Gy per 15 fractions over 3 weeks (without lung compensation calculation). In both the EH-MRT and MRT group, the total radiation doses to the mediastinum were similar with a median of 40 Gy. The median follow-up time after surgery was 63 months and no patients were lost to follow-up. RESULTS: Only one of the 23 patients with EH-MRT relapsed. On the other hand, eight of the 20 with MRT relapsed, six of whom died of disease. The pleura was the most common site of failure. At 5 years, the relapse-free rate was 100% for those receiving EH-MRT and 66% for those with MRT (p = 0.03); the overall survival rate was 96% for those with EH-MRT, and 74% for those with MRT (p: not significant). The only significant treatment-related complication was radiation pneumonitis requiring treatment, in one patient who received MRT and three who received EH-MRT, including one death of a 72-year-old man and one 68-year-old woman with severe lung fibrosis. CONCLUSION: Except for elderly patients, EH-MRT following a macroscopically complete resection appears to be safe and feasible, and can reduce intrathoracic relapses.

Adult↗
PubMed1996

Aberrant hypermethylation at the bcl-2 locus at 18q21 in human lung cancers.

Accumulating evidence suggests that altered DNA methylation may play a role in the oncogenesis of human neoplasms, including lung cancer. The presence of aberrant hypermthylations at 3p, 9p, 11p, ad 17p, which are known to be hot spots for allele loss in lung cancers, is suggested to be a reflection of the existence of tumor suppressor genes in these chromosomal regions. In the present study, we investigated the methylation status of the Rb locus at 13q14 as well as that of the bcl-2 locus at 18q21 in 134 lung cancer specimens, representing all major histological subtypes. As a result, 18q21 was identified to be the fifth chromosomal region affected by frequent tumor-specific aberrant hypermethylation in lung cancers. The occurrence of aberrant hypermethylation at the bcl-2 locus at 18q21 was restricted to non-small cell lung cancers, and among non-small cell lung cancers, such epigenetic aberrations were observed most frequently in adenocarcinomas without any association with bcl-2 expression. Interestingly, allelic loss at the bcl-2 locus was also seen in 40% (7 of 17 informative cases) of adenocarcinomas; this frequency was also the highest among values for the various histological subtypes of lung cancers. These results suggest that aberrant hypermethylation at the bcl-2 locus may be a reflection of a putative tumor suppressor gene residing at 18q21, and aberrant hypermethylation might play a role in its inactivation. In contrast, altered methylation status of the Rb locus appears to be quite rare in lung cancers, if present at all.

Adenocarcinoma↗
PubMed1996

Allelic-expression imbalance of the insulin-like growth factor 2 gene in hepatocellular carcinoma and underlying disease.

It has been well documented that the liver is an exceptional organ in which the monoallelic expression of insulin-like growth factor 2 (IGF2) due to genomic imprinting is relaxed during the postnatal period, resulting in biallelic expression thereafter. In the present study, changes in the status of genomic imprinting were examined in 15 hepatocellular carcinomas (HCCs) as well as in 29 liver biopsies of chronic hepatitis or liver cirrhosis without clinical evidence of HCC, following screening for heterozygotes with an ApaI polymorphism in IGF2 in 34 HCCs and 80 such non-HCC cases. Extreme allelic-expression imbalance, leading to restoration of monoallelic IGF2 expression, was observed in 15 (100%) of 15 informative HCCs for the polymorphism with this monoallelic IGF2 expression appearing to be non-random from the paternal allele. Interestingly, the same allelic-expression imbalance was also present in a significant fraction of noncancerous liver specimens of patients with underlying disease known to be associated with HCC development. In contrast, the status of genomic imprinting of H19, another gene closely mapped at 11p15 under opposite imprinting, was strictly maintained in seven (100%) of seven cases informative for an RsaI polymorphism of H19. Together with the previous reports on altered genomic imprinting of IGF2 and H19 in embryonal lesions such as Wilms tumors as well as in lung cancers, the results suggest that perturbations of imprinting status occur as locus and tumor-type specific events in the development of human cancers.

Alleles↗
PubMed1996

Selective maternal-allele loss in human lung cancers of the maternally expressed p57KIP2 gene at 11p15.5.

Genomic imprinting at 11p15 is suggested to play a role in certain pediatric tumors such as Wilms' tumor, based on the findings of selective maternal loss of this chromosomal region. Although the allele loss at 11p15 is also frequent in a number of cancers of adults including lung, breast, and bladder cancers, possible involvement of genomic imprinting in these tumors has not been investigated extensively. p57KIP2, a newly described member of the p21 cyclin-dependent kinase (CDK) inhibitor family which is thought to negatively regulate the cell cycle at the G1 checkpoint, has been mapped to 11p15. In the present study, we searched for somatic p57KIP2 mutations in lung cancer, but failed to find such alterations. Interestingly, however, we found that the p57KIP2 gene is imprinted with maternal expression and that the maternal alleles had been selectively lost in 11 of 13 (85%) lung cancer cases carrying 11p15 deletions, this being a significant bias (p=0.01). These data provide the first evidence that genomic imprinting may play a role in the oncogenesis of not only rare pediatric tumors but also this common cancer of adults, suggesting that the imprinted p57KIP2 CDK inhibitor gene is a potential target for maternally biased 11p15 deletions.

Adult↗
PubMed1996

Overexpression of MP41 gene in a transformed endothelial cell line correlates with the increased fibronectin expression and a decreased incidence of tumorigenicity.

mp41 gene, which was originally identified as a gene regulated by the circadian clock, showed some similarity with yeast cell cycle regulator, CDC25, and its mRNA expression is restricted mainly to non-dividing cell. To elucidate the growth regulatory of mp41, mp41 cDNA was transfected into a transformed human endothelial cell line. All stable mp41 transformants showed increased levels of fibronectin expression and reduced migratory activity in vitro. Although the in vitro growth rate of mp41 transformants and their ability to grow in soft agar were not significantly altered, their tumor formation was suppressed significantly in nude mice. The results imply that mp41 gene overexpression altered the tumorigenicity associated with fibronectin elevation in stable transformation of the transformed endothelial cell line.

Animals↗
PubMed1996

Molecular cloning of a human cDNA encoding a trifunctional enzyme of carbamoyl-phosphate synthetase-aspartate transcarbamoylase-dihydroorotase in de Novo pyrimidine synthesis.

A human CAD cDNA encoding a trifunctional enzyme of carbamoylphosphate synthetase-aspartate transcarbamoylase-dihydroorotase, which catalyzes the first three steps of de novo pyrimidine nucleotide biosynthesis, was cloned from a human fibroblast cell line of TIG-1-20 by polymerase chain reaction (PCR). The predicted open reading frame encodes a protein of 2,225 amino acids with a deduced molecular weight (Mr) OF 242,913. The deduced amino acid sequence exhibits 95.3 and 76.1% identity with the CAD sequences of hamster and Squalus acanthias. The DNA fragment of 6,679 bp containing the full-length coding sequence was amplified by nested PCR using the first-strand cDNA of human cell lines of TIG-1-20 and COLO205 as a template. Southern blot analysis suggested that the CAD gene exists as a single copy in the human genome.

Amino Acid Sequence↗
PubMed1996

Molecular cloning of Xenopus activin type I receptor and the analysis of its expression during embryogenesis.

We cloned cDNAs coding for the Xenopus counterparts of a type I activin receptor. The cDNA clones were predicted to encode 56kd proteins, namely XAR3 and XAR4 proteins. The two proteins are highly homologous to each other, showing 96% identity in the amino acid sequences. The GST-fused kinase domain of XAR3 autophosphorylated itself in vitro on threonine residues. The expression of XAR4 was found throughout embryogenesis, from oocytes to tailbud embryos, and also in adult tissues. By whole mount in situ hybridization, the XAR4 transcripts were detected in the animal half of blastulae and dorsally in gastrulae and neurulae. In tadpoles, the transcript was seen in the brain and around the otic vesicles. These results show that the activin type I receptor is expressed during Xenopus embryogenesis and suggest that the type I and II receptors are expressed together both temporally and spatially, supporting the idea that activin induces mesoderm in the embryo through activation of the two types of receptors.

Activin Receptors↗