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T Kudo

Publications and source records attributed to T Kudo.

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

Detection of c-erbB-2 and FGF-3 (INT-2) gene amplification in epithelial ovarian cancer.

We examined gene amplifications of the c-erbB-2 and FGF-3 gene in 48 epithelial ovarian cancers by differential PCR and addressed their association with clinico-pathological features including clinical outcome. Overall, 25.0 and 20.8% of ovarian cancers displayed amplified c-erbB-2 or FGF-3 gene, respectively. Amplification of the c-erbB-2 gene was significantly associated with particular histological cell types, higher histological grade, and low levels of serous CA125. However, there was no correlation between c-erbB-2 gene amplification and patient outcome. No correlation was observed between FGF-3 gene amplification and any clinico-pathological features including overall survival. These findings suggested that c-erbB-2 or FGF-3 gene amplification might be one of the oncogenic events implicated in the development of ovarian cancers, yet is not a useful prognostic marker.

Adult↗
PubMed2000

[Severe hemolysis and SIADH-like symptoms induced by vincristine in an ALL patient with liver cirrhosis].

An 11-year-old boy was diagnosed as having acute lymphoblastic leukemia (ALL, L1) in 1987 and underwent treatment with an ALL high-risk protocol (prednisolone, vincristine (VCR), daunorubicin, 1-asparaginase), which resulted in complete remission. In 1990 he developed chronic hepatitis C and received interferon therapy. In December 1994, ALL recurred, and the patient was treated with VCR. He subsequently developed severe hemolysis (Hb 12.5 g/dl-->6.8 g/dl) with increases of indirect bilirubin, AST, and LDH. Furthermore, symptoms resembling a syndrome of inappropriate secretion of ADH (SIADH) and DIC developed. Upon incubation of the patient's red blood cells with VCR in vitro, extreme deformity of the cells was observed. These findings suggested that splenomegaly, due to liver cirrhosis which had developed rapidly from chronic hepatitis C while the patient was in an immunosuppressed state induced by anticancer drugs, had trapped the deformed red blood cells and resulted in severe hemolysis. The patient died on the 165th day after admission due to liver failure.

Adolescent↗
PubMed1999

Phylogenetic relationships of symbiotic spirochetes in the gut of diverse termites.

Phylogenetic relationships of symbiotic spirochetes in the gut of diverse termites were analyzed without cultivation of these microorganisms. A portion of the 16S rDNA (ca. 850 bp) was amplified directly from DNA of the mixed population in the gut by PCR and cloned. A total of 30 spirochetal phylotypes affiliated with the treponemes were identified from four termite species and they were compared with those already reported from other termites. They represented separate lines of descent from any known species of Treponema, and they were divided into two discrete clusters; one was related to Spirochaeta stenostrepta and S. caldaria, and the other was grouped together with members of the Treponema bryantii subgroup. Although some sequences from evolutionarily related termites showed close similarity, most of the sequences of spirochetes were dissimilar among different termite species, and spirochetal sequences from a single termite species occurred in several distinct phylogenetic positions. These findings suggest that termites constitute a rich reservoir of novel spirochetal diversity and that evolution of the symbiosis is not simple.

Animals↗
PubMed1999

Up-regulation of Lewis enzyme (Fuc-TIII) and plasma-type alpha1,3fucosyltransferase (Fuc-TVI) expression determines the augmented expression of sialyl Lewis x antigen in non-small cell lung cancer.

Sialyl Lewis a and x antigens are well-known tumor-associated antigens expressed in many cancer tissues. The expression of the genes encoding 5 alpha1,3fucosyltransferases, which are able to synthesize the sialyl Lewis antigens, was examined in normal and cancerous lung tissues of patients with non-small cell lung carcinoma. In all 20 cases examined, the transcripts only for the Lewis gene, encoding the Lewis enzyme (alpha1,3/4fucosyltransferase, Fuc-TIII), were abundantly expressed in lung tissue, and interestingly they were markedly up-regulated in the lung cancer tissues of all 20 cases in comparison with normal lung tissues. Myeloid-type alpha1,3fucosyltransferase (Fuc-TIV) was expressed at an intermediate level but was not up-regulated in lung cancer tissues. The transcripts for plasma-type alpha1,3fucosyltransferase (Fuc-TVI) gene were detected at a very low level but were apparently up-regulated in cancer tissues. Fuc-TVI was found to exhibit stronger relative activity for sialyl Lewis x synthesis (almost 6. 4-fold that of Fuc-TIII). The amount of sialyl Lewis x antigen on mucins in the lung cancer tissues was found to be determined by both enzymes, the Lewis enzyme (Fuc-TIII) and Fuc-TVI. However, the amount of the sialyl Lewis a antigens was not determined by any of the alpha1,3-fucosyltransferases, although the expression of sialyl Lewis a antigens definitely required the Lewis enzyme.

Adenocarcinoma↗
PubMed1999

Casein kinase II is responsible for phosphorylation of NF-L at Ser-473.

Ser-473 is solely phosphorylated in vivo in the tail region of neurofilament L (NF-L). With peptides including the native phosphorylation site, it was not possible to locate responsible kinases. We therefore adopted full-length dephosphorylated NF-L as the substrate, and employed MALDI/TOF (matrix-assisted laser desorption and ionization/time of flight) mass spectrometry and a site-specific phosphorylation-dependent antibody recognizing Ser-473 phosphorylation. The antibody showed that casein kinase I (CK I) as well as casein kinase II (CK II) phosphorylated Ser-473 in vitro, while neither GSK-3beta nor calcium/calmodulin-dependent protein kinase II did so. However, the mass spectra of the tail fragments of the phosphorylated NF-L indicated that CK II was the kinase mediating Ser-473 phosphorylation in vitro as opposed to CK I, because CK I phosphorylated another site as well as Ser-473 in vitro. The antibody also demonstrated that NF-L phosphorylated at Ser-473 was abundant in the neuronal perikarya of the rat cortex, indicating that phosphorylation of Ser-473 may take place there. This result may support the suggestion that CK II is the kinase responsible for Ser-473 phosphorylation. Despite many reports showing that CK I mediates phosphorylation of neurofilaments, CK II may phosphorylate NF-L in vivo.

Amino Acid Sequence↗
PubMed1999

Alpha1,3-fucosyltransferase IX (Fuc-TIX) is very highly conserved between human and mouse; molecular cloning, characterization and tissue distribution of human Fuc-TIX.

The amino acid sequence of Fuc-TIX is very highly conserved between mouse and human. The number of non-synonymous nucleotide substitutions of the Fuc-TIX gene between human and mouse was strikingly low, and almost equivalent to that of the alpha-actin gene. This indicates that Fuc-TIX is under a strong selective pressure of preservation during evolution. The human Fuc-TIX (hFuc-TIX) showed a unique characteristics, i.e. hFuc-TIX was not activated by Mn2+ and Co2+, whereas hFuc-TIV and hFuc-TVI were activated by the cations. The hFuc-TIX transcripts were abundantly expressed in brain and stomach, and interestingly were detected in spleen and peripheral blood leukocytes.

Amino Acid Sequence↗
PubMed1999

Cloning, expression, and characterization of a novel UDP-galactose:beta-N-acetylglucosamine beta1,3-galactosyltransferase (beta3Gal-T5) responsible for synthesis of type 1 chain in colorectal and pancreatic epithelia and tumor cells derived therefrom.

The sialyl Lewis a antigen is a well known tumor marker, CA19-9, which is frequently elevated in the serum in gastrointestinal and pancreatic cancers. UDP-galactose:N-acetylglucosamine beta1, 3-galactosyltransferase(s) (beta3Gal-Ts) are required for the synthesis of the sialyl Lewis a epitope. In the present study, a novel beta3Gal-T, named beta3Gal-T5, was isolated from a Colo205 cDNA library using a degenerate primer strategy based on the amino acid sequences of the four human beta3Gal-T genes cloned to date. Transfection experiments demonstrated that HCT-15 cells transfected with the beta3Gal-T5 gene expressed all the type 1 Lewis antigens. In gastrointestinal and pancreatic cancer cell lines, the amounts of beta3Gal-T5 transcripts were quite well correlated with the amounts of the sialyl Lewis a antigens. The beta1,3Gal-T activity toward agalacto-lacto-N-neotetraose was also well correlated with the amounts of beta3Gal-T5 transcripts in a series of cultured cancer cells, and in Namalwa and HCT-15 cells transfected with the beta3Gal-T5 gene. Thus, the beta3Gal-T5 gene is the most probable candidate responsible for the synthesis of the type 1 Lewis antigens in gastrointestinal and pancreatic epithelia and tumor cells derived therefrom. In addition, beta3Gal-T5 is a key enzyme that determines the amounts of the type 1 Lewis antigens including the sialyl Lewis a antigen.

Amino Acid Sequence↗
PubMed1999

Structural characterization of the chicken SF-1/Ad4BP gene.

SF-1/Ad4BP was identified as a master regulator controlling steroidogenic P-450 genes and belongs to the steroid hormone receptor superfamily. It is expressed in the adrenal cortex, gonads, and pituitary gonadotroph. Targeted disruption of the mouse SF-1/Ad4BP gene showed that it plays a critical role in the development of the steroidogenic tissues and pituitary gonadotroph. We have recently cloned the chicken SF-1/Ad4BP cDNA and have now cloned the chicken SF-1/Ad4BP gene and analyzed its promoter activity. This gene consists of seven exons as well as mammalian counterparts and spans about 15 kb. In mice, the gene encodes another protein, ELP, but we could not find the open reading frame of ELP in the chicken SF-1/Ad4BP gene. The promoter of this gene included five putative cis elements (E, CCAAT, GC and TATA boxes and a GA-rich element), although no TATA box has been found in mammalian counterparts. The E and CCAAT boxes moderately affected promoter activity and the GA-rich element and TATA box were essential for the expression of the chicken SF-1/Ad4BP gene.

Amino Acid Sequence↗
PubMed1999

IPP isomerase, an enzyme of mevalonate pathway, is preferentially expressed in postnatal cortical neurons and induced after nerve transection.

To understand the molecular mechanisms underlying the developmental processes of the cerebral cortex, we screened genes whose mRNA expression was up-regulated in neonatal in the rat cortex to a greater extent than in adult by differential display and obtained five genes. Among these genes, we focused on pyrophosphate (isopentenyl diphosphate, dimethylallyl diphosphate: IPP) isomerase gene, the product of which is known as an enzyme of the mevalonate pathway. Rat IPP isomerase was recently cloned and the gene expression was shown to be dependent on the activation of the mevalonate pathway. Its expression and roles in the brain, however, have not been investigated hitherto. In the present study, Northern blots and in situ hybridization analysis showed that at embryonic stage weak signals for IPP mRNA were diffusely detected in the CNS, and the signal in the cortex became intense at postnatal day 1 and maximized in almost all neurons of all layers at postnatal day 7 with a subsequent reduction. At 8 weeks, the expression of IPP isomerase mRNA in neurons decreased, while it was detected in the oligodendrocytes in the regions containing abundant nerve fibers. These findings suggested that IPP isomerase contributes to postnatal neuronal maturation and myelination. We also demonstrated that IPP isomerase mRNA is induced after nerve axotomy, which suggests a relationship between neuronal regeneration and IPP isomerase. Taken together, these results suggest that elevation of IPP isomerase mRNA levels in neurons contributes to construction of nerve fibers both during the postnatal period in the cortex and their regeneration.

Animals↗
PubMed1999

SEA-scFv as a bifunctional antibody: construction of a bacterial expression system and its functional analysis.

A SEA-antibody single chain Fv (SEA-scFv) fusion protein was produced by bacterial expression system in this study. SEA-scFv has both staphylococcal enterotoxin A (SEA) effects and antibody activity directed at the epithelial mucin core protein MUC1, a cancer associated antigen. It was expressed mostly in the cytoplasm as an insoluble form. The gene product was solubilized by guanidine hydrochloride, refolded by conventional dilution method, and purified using metal-chelating chromatography. The resulting SEA-scFv fusion protein preparation was found to react with MUC1 and MHC class II antigens and had the ability to enhance cytotoxicity of lymphokine activated killer cells with a T cell phenotype against a human bile duct carcinoma cell line, TFK-1, expressing MUC1. This genetically engineered SEA-scFv fusion protein promises to be an important reagent for cancer immunotherapy.

Antibodies, Bispecific↗
PubMed1999

Phylogenetic relationships of symbiotic methanogens in diverse termites.

Termites harbor symbiotic microorganisms in their gut which emit methane. The phylogeny of the termite methanogens was inferred without cultivation based on nucleotide sequences of PCR-amplified 16S ribosomal RNA genes. Seven methanogen sequences from four termite species were newly isolated, and together with those previously published, these sequences were phylogenetically compared. The termite methanogen sequences were divided into three clusters. Two clusters of sequences, derived from the gut DNA of so-called higher termites, were related to methanogens in the orders Methanosarcinales or Methanomicrobiales. All of the sequences in the case of lower termites were closely related to the genus Methanobrevibacter. However, most of the termite symbionts were found to be distinct from known methanogens. They are not dispersed among diverse methanogen species, but rather formed unique lineages in the phylogenetic trees.

Animals↗
PubMed1999

Cardiomegaly in the juvenile visceral steatosis (JVS) mouse is reduced with acute elevation of heart short-chain acyl-carnitine level after L-carnitine injection.

The long-term administration of L-carnitine was very effective in preventing cardiomegaly in juvenile visceral steatosis (JVS) mice, which was confirmed by heart weight as well as the lipid contents in heart tissue. After i.p. injection of L-carnitine, the concentration of free carnitine in heart remained constant, although serum free carnitine level increased up to 80-fold. On the other hand, a significant increase in short-chain acyl-carnitine level in heart was observed. These results suggest that increased levels of short-chain acyl-carnitine, not free carnitine, might be a key compound in the protective effect of L-carnitine administration in JVS mice.

Aging↗
PubMed1999

Analyses of a Bacillus subtilis homologue of the Na+/H+ antiporter gene which is important for pH homeostasis of alkaliphilic Bacillus sp. C-125.

Bacillus subtilis was revealed to have a homologous region to the DNA fragment responsible for alkaliphily of alkaliphilic Bacillus sp. C-125 on the genome, as reported previously [1]. The yufT gene on the B. subtilis genome showed a significant similarity with ORF1 of Bacillus sp. C-125, which is related to membrane potential (DeltaPsi)-driven Na+/H+ antiport activity and is important for pH homeostasis in an alkaline condition. Disruption of the yufT gene resulted in the decrease of Na+/H+ antiport activity, and the growth of the yufT disrupted strain was impaired with an increase in the external Na+ concentration. We conclude that the yufT gene encodes a Na+/H+ antiporter, which has a dominant role in the extrusion of cytotoxic Na+.

Bacillus subtilis↗
PubMed1999

Histomorphometric evaluation of the effects of ovariectomy on bone turnover in rat caudal vertebrae.

The purpose of this study was to learn whether caudal vertebrae can be used to evaluate the effects of ovariectomy (OVX) in rats. Seven-month-old female Wistar rats were divided into two groups: the OVX group and the untreated control group. All rats were killed at 8 weeks and their 4th lumbar (L4), 1st caudal (C1), 3rd caudal (C3), and 5th caudal (C5) vertebrae were processed undecalcified and sectioned with Villanueva bone stain for quantitative bone histomorphometry. Both length of vertebral bodies and the cancellous tissue area in C1 were similar in size to L4 but significantly bigger than C3 and C5. Within the groups, cancellous bone volume (BV/TV) and trabecular thickness in both groups gradually increased in caudal vertebrae in relation to the distal direction. Between the groups, OVX rats exhibited a significantly lower BV/TV relative to control rats at L4 and C1, however, no significant difference were seen at C3 and C5. Bone formation-related parameters such as osteoid and mineralizing surface, and eroded surface were higher in the OVX group than in the control group in caudal as well as in lumbar vertebrae. By quantitative analysis of bone marrow composition, yellow marrow volume in C3 and C5 was significantly higher than that in L4 and C1, in both groups. Our results suggest that C1 is similar to L4 in size, bone turnover, and bone marrow composition. However, further experiments are needed to evaluate the possibility that C1 vertebra could be used as an alternative site for histomorphometric evaluation of bone changes in OVX rats.

Animals↗
PubMed1999

Presenilin-2 mutation and polymorphism in Japanese Alzheimer disease patients.

The Asn141Ile mutation of the presenilin 2 gene is responsible for familial early-onset Alzheimer disease found in Volga-German kindreds. However, the genetic influence of presenilin 2 gene on sporadic Alzheimer disease remains unknown. In this study, the frequency of the mutation and genetic association with the presenilin 2 locus were investigated in Japanese sporadic cases. The Asn141Ile mutation was not found in 88 cases of sporadic Alzheimer disease or 13 unrelated cases of familial Alzheimer disease. Fifty cases of late onset sporadic Alzheimer disease and 50 age-matched controls indicated no association with an exon 3 polymorphism of the presenilin 2 gene. These results indicate that the presenilin 2 mutation is not a major cause of Alzheimer disease.

Age of Onset↗
PubMed1999

Telomerase and proliferative activity in placenta from women with and without fetal growth restriction.

OBJECTIVE: To analyze telomerase and proliferative activity in placenta from women with and without fetal growth restriction (FGR). METHODS: Telomerase activity was analyzed in 30 first-trimester chorionic villi specimens (group A) and in 28 second- and third-trimester placenta specimens (group B) from women without FGR. Telomerase activity also was analyzed in 11 placenta specimens from women with asymmetric FGR (group C). The proliferative activity of these 69 specimens was assessed by immunohistochemical staining, using the MIB-1 monoclonal antibody. RESULTS: Telomerase activity was detected in 28 (93.3%) of 30 chorionic villi specimens and in 18 (64.3%) of 28 placenta specimens without FGR. In contrast, no telomerase activity was exhibited in the placenta specimens from any of the 11 women with asymmetric FGR by telomeric repeat amplification protocol assay. Telomerase activity also was detected by in situ telomeric repeat amplification protocol assay in trophoblastic cells from women without FGR but not in trophoblastic cells from women with asymmetric FGR. Thus, telomerase activity was detected significantly more often in groups A and B than in group C (P < .01). The rate of proliferative activity, evident as positive MIB-1 staining in trophoblastic cells, in groups A and B (28.1+/-1.7% and 7.0 +/-2.9%, respectively) was significantly higher than that in group C (1.9+/-0.6%; P < .01). CONCLUSION: Telomerase and proliferative activity were minimal in placenta from women with asymmetrical FGR, suggesting placental senescence with asymmetrical FGR.

Cell Division↗