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T Koide

Publications and source records attributed to T Koide.

At least 145 records · Page 8Linked to original sources
PubMed1996

[A clinical study of renal pelvic and ureteral cancer associated with bladder cancer].

We reviewed 45 cases of transitional cell carcinoma of the renal pelvis and ureter with reference to the coexistence or subsequent development of bladder cancer. Bladder cancer was associated with an upper urinary tract neoplasm in 26 of the 45 cases. The 5-year survival rate for coexistence of bladder cancer was 56% and that for subsequent bladder cancer was 65.6%. The 5-year survival rate for 19 cases unrelated with bladder cancer was 46.7%. Therefore, there was no significant difference among the three groups. As to degree of the malignancy of the renal pelvis and ureter, the 5-year survival rate was 73.7% for G1 and G2 and 26.2% for G3. As to the depth of invasion, of the renal pelvis and ureter the 5-year survival rate was 71.8% and 31.1% in the patients with stage of T1, T2 and T3, T4. The prognosis of cancer of the upper urinary tract depended on the degree of the malignancy, and the depth of invasion. Ninety two percent of subsequent bladder cancer was detected within 2 years after resection of the primary cancer.

Adult↗
PubMed1996

Case report: development of hepatocellular carcinoma in a patient with chronic hepatitis C infection after a complete and sustained response to interferon-alpha.

A 60-year-old man with a chronic hepatitis C virus (HCV) infection and histological features of chronic active hepatitis was treated with interferon-alpha (IFN). He successfully responded to IFN with normalization of serum ALT and disappearance of serum HCV-RNA. His liver biochemistry profile remained normal and serum HCV-RNA was not detected throughout the entire follow-up period. One year later, a small hepatocellular carcinoma (HCC) was detected by routine ultrasonographic screening. Laparotomy revealed a small tumour with no metastasis and the non-tumorous liver demonstrated macronodular cirrhosis. Although no space-occupying lesions were detected by frequent radiological examinations prior to IFN therapy, the small size of the tumour suggested de novo development of HCC. Patients with chronic HCV infection, including those who have complete responses to IFN and lack clinical and histological evidence of cirrhosis, should be followed up for the potential development of HCC.

Antiviral Agents↗
PubMed1996

[Hyperuricosuria and urolithiasis].

Hyperuricosuria with or without hypercalciuria amounted to about 23% of the possible cause of urolithiasis in my clinical experience. Approximately three forth of urolithiasis caused by hyperuricosuria was calcium oxalate stones and the rest was uric acid stones. Uric acid is one of the composition of urinary stones itself, but it has an activity of calcium oxalate stone formation. The hypotheses why the uric acid induced calcium oxalate stones were introduced. The preventive effect of allopurinol on the recurrent calcium oxalate stone formers was proved in our previous study which may revealed the urinary uric acid promoted calcium oxalate stone formation or masked the inhibitory activity of urinary macromolecular inhibitors. On the basis of above statement, I emphasize the importance of the treatment of hyperuricosuria in preventing urinary stones.

Calcium Oxalate↗
PubMed1995

Localization of trkB and low-affinity nerve growth factor receptor mRNA in the developing rat retina.

The localization of trkB and low-affinity nerve growth factor receptor (LNGFR) mRNAs in the developing rat retina was examined by in situ hybridization. TrkB mRNA was expressed in the ganglion cell layer (GCL), in the inner border of the neuroblastic layer (NBL), and the inner border of the inner nuclear layer (INL). LNGFR mRNA was expressed in the GCL, in almost full thickness of the NBL, and in the intermediate part of the INL. Although both trkB mRNA and LNGFR mRNA were expressed in the GCL, the expression pattern was different between these mRNAs; trkB mRNA was expressed in almost all cells in the GCL uniformly and the expression of LNGFR mRNA varied greatly from cell to cell. In addition, the expression of both mRNAs, especially LNGFR mRNA seemed to be down-regulated at P7, when programmed cell death of the RGCs was prominent. These observations indicate that LNGFR may modulate the function of trkB and that trkB and LNGFR play important roles in the development and maintenance of the RGCs.

Animals↗
PubMed1995

Warfarin causes the degradation of protein C precursor in the endoplasmic reticulum.

Warfarin, an antagonist of vitamin K, is known to disrupt the microsomal vitamin K cycle, which results in a decrease in the plasma level of protein C, an anticoagulant factor, as well as some other vitamin K-dependent coagulation factors. Here, we examined the effect of warfarin on the secretion of recombinant protein C expressed in human kidney 293 or BHK cells. In transient expression, warfarin caused a 2-4-fold decrease in the quantity of protein C secreted, compared to findings with vitamin K-treated cells. Pulse-chase experiments using stable cells showed that, although recombinant protein C was secreted in the presence of vitamin K, the decrease in the total amount of radioactivity in the warfarin-treated cells suggested intracellular degradation. This degradation depended on the concentration of warfarin and was not inhibited by an endoplasmic reticulum (ER)-Golgi transport inhibitor (brefeldin A) or by lysosomotropic inhibitors (chloroquine and NH4Cl). Thus, protein C synthesized in the presence of warfarin is probably selectively degraded, and this degradation occurs in a pre-Golgi, nonlysosomal compartment. Among the protease inhibitors tested, N-alpha-acetyl-Leu-Leu-methioninal and N-alpha-acetyl-Leu-Leu-norleucinal blocked the degradation of protein C precursor synthesized in the presence of warfarin, and the precursor accumulated intracellularly, in a dose-dependent manner. Both inhibitors, however, did not disturb the secretion of protein C precursor in the vitamin K-treated cells. Thus, a cysteine protease(s) appeared to be responsible for the degradation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Hotspots of homologous recombination in mouse meiosis.

The molecular mapping of recombinational breakpoints in the proximal region of the mouse MHC has revealed four hotspots at which breakpoints are clustered. A direct comparison of the nucleotide sequences of two independent hotspots revealed common molecular elements: a consensus sequence of the middle-repetitive MT-family, a repeat of tetramer sequences and a sequence homologous to a solitary LTR of mouse retroviruses. Extremely high frequency of recombination is observed at these hotspots when particular MHC haplotypes are used in genetic crosses. Wild mouse-derived wm7 haplotype instigates recombination at the hotspot located at the 3'-end of the Lmp-2 gene only during female meiosis. Fine genetic analysis demonstrated that the wm7 haplotype carries a genetic factor to instigate recombination and another factor to suppress recombination specifically during male meiosis. In addition, there is no dose effect of the hotspot on frequency of recombination. Finally, we described an attempt to establish an efficient in vitro assay system for monitoring recombination using plasmid DNAs that contain the Lmp-2 hotspot and nuclear extracts prepared from mouse testis.

Animals↗
PubMed1995

Disulfide bond-forming reaction using a dimethyl sulfoxide/aqueous HCl system and its application to regioselective two disulfide bond formation.

Disulfide bond formation in S-acetamidomethyl (Acm) cysteine-containing peptides by successive treatments with silver trifluoromethanesulfonate (AgOTf) and dimethyl sulfoxide (DMSO)/aqueous HCl is described. An S-Acm cysteine was found to be quantitatively converted into cysteine by deprotection of the Acm group with AgOTf followed by DMSO/aqueous HCl treatment. Under these reaction conditions, no significant side reactions were observed with oxidation-sensitive amino acids such as Met, Tyr and Trp. Oxytocin and a Trp-containing peptide, urotensin II, were prepared by this method. Furthermore, regioselective two disulfide bond formation was found to be feasible by the combination of air oxidation and the AgOTf-DMSO/HCl system. This strategy has been successfully applied to the syntheses of tachyplesin I and endothelin I, which have two disulfide bonds and a Trp residue in the molecule.

Amino Acid Sequence↗
PubMed1995

The inhibitory effect of kampou extracts on in vitro calcium oxalate crystallization and in vivo stone formation in an animal model.

Kampou medicine is a traditional Japanese therapeutic system which originated in China and was used to treat various diseases for hundreds of years until it was superseded by Western medicine. In recent years, there has been a resurgence of interest in Kampou medicine among many physicians. Unfortunately, however, little evaluation has been performed using objective scientific methods until now, and the pharmacodynamics of Kampou medicine are still unclear. Generally speaking, Kampou medicine has been shown to have fewer side-effects than Western medicine based on the experience gained from its long usage. We first selected 16 Kampou extracts for screening as possible calcium oxalate stone prophylactic agents in vitro. This resulted in the selection of two kinds of Kampou extracts, Takusya and Kagosou, as potential Kampou extracts for stone prophylaxis. Next, these two Kampou extracts were tested in vivo for their effects on stone formation in an animal model. Takusya showed significant stone prophylaxis, while Kagosou did not. Lastly, Chorei-to, which contains Takusya and has been approved for prescription as a Kampou medicine for urolithiasis patients in Japan, was examined in vivo at two different concentrations. As a result, a low dose of Chorei-to which corresponded to the human daily dose per unit of body weight exhibited apparent stone prophylaxis, despite the disadvantage of decreasing citrate excretion. In contrast, high doses of Chorei-to did not exhibit stone prophylaxis in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Suppression of tumor cell growth by anthocyanins in vitro.

Bioflavonoids, extracted from flower petals, were examined for their growth inhibitory effect on cells in culture. They were found to significantly suppress the growth of the cultured cells. Anthocyanins tended to show greater inhibitory effect than other flavonoids. Commercially synthesized or purified aglycones of flavonoids were also studied for their suppression of tumor cells. The anthocyanins were more effective than other flavonoid aglycones, although the aglycones were easily inactivated under the culture conditions.

Anthocyanins↗
PubMed1995

[The effect of takusha and kagosou on calcium oxalate renal stones in rats].

We examined the inhibitory effect of the two Kampo medicines, takusha and kagosou on the formation of calcium oxalate renal stones induced by ethylene glycol (EG) and 1 alpha(OH)D3 (1 alpha-D3) in rats. Wistar strain rats were divided into 4 groups (A: normal control, B: stone, C: kagosou, D: takusya). There was no significant difference in urinary calcium excretion or oxalate excretion between the stone group and kampo medicine groups. The calcium content of the kidneys was significantly lower in the takusha group than in the other two groups (Stone group and kagosou group). Takusha was effective in preventing oxalate stone formation in rats. Kagosou, which had strong inhibitory effect on calcium oxalate crystal growth and aggregation in vitro as well as takusha, was not effective against in vivo calcium oxalate stone formation in rats. These findings suggest that takusha prevents the formation of calcium oxalate stone by inhibiting calcium oxalate crystal growth and aggregation.

Animals↗
PubMed1995

Use of confocal laser scanning microscopy in radioautographic study.

Confocal laser scanning microscopy was used to visualize the radioautograph at the light-microscope level. Confocal reflectance images from developed silver grains were overlaid with the differential interference contrast image of the tissue. With this technique, a well-focused radioautograph can be taken of both tissue sections and all of the silver grains dispersed in the thick emulsion layer. Further application of this microscopy is discussed.

Animals↗
PubMed1995

[Three cases of clinically diagnosed corticobasal degeneration--neuroimaging studies with MRI, SPECT and PET].

We report three cases of clinically diagnosed corticobasal degeneration: a 63-year-old male, a 63-year-old female and a 62-year-old female. All the three patients exhibited asymmetric limb-kinetic apraxia and extrapyramidal signs. Neuroimaging studies with MRI, 123I-IMP SPECT and FDG-PET were performed in each of the three cases and FDOPA-PET was performed in patient 1. MRI analysis showed asymmetric cortical atrophy, especially in the parietal cortex, in all the three cases. 123I-IMP SPECT analysis revealed asymmetric reduction of the cerebral blood flow, in accordance with the MRI findings. FDG-PET analysis showed marked asymmetric reduction (> or = 10%) of cerebral metabolic rates for glucose (CMRGlc) in the lateral frontal cortex, lateral posterior frontal cortex and primary motor and sensory cortex in all the patients, although the asymmetry in the thalamus which had been described as a characteristic CBD finding in previous reports was not observed in any of the patients in our study. FDOPA-PET analysis revealed reduction of uptake in both the putamen and caudate nucleus, predominantly in the caudate nucleus, which suggests that the FDOPA-PET findings correlate with the extrapyramidal signs observed in the case of the 63-year-old male.

Basal Ganglia↗
PubMed1995

Identification and genetic analysis of a common molecular variant of histidine-rich glycoprotein with a difference of 2kD in apparent molecular weight.

Two forms of histidine-rich glycoprotein (HRG) were detected on SDS-PAGE by silver staining and immunoblotting after isolation of the protein from pooled plasma using immuno-affinity chromatography followed by chromatography with heparin-Sepharose. Both forms were single-chain molecules and the apparent molecular weights of form 1 and form 2 were 77 kD and 75 kD respectively. Mendelian inheritance of both HRG forms was observed in four families with 24 informative meioses, strongly suggesting that the two forms are encoded by different alleles. The frequency of form 1 and form 2 in a group of 36 individuals was 0.35 and 0.65 respectively. The difference between the two molecular variants was studied by direct sequence analysis of amplified exons of the HRG gene from 6 individuals who were homozygous either for form 1 or form 2. Five amino acid polymorphisms in three different exons were observed: Ile/Thr in exon4; Pro/Ser in exon 5; His/Arg, Arg/Cys and Asn/Ile in exon 7. Analysis of these polymorphisms in 20 volunteers showed that only the Pro/Ser polymorphism at position 186 in exon 5 was coupled to the form of the HRG protein. Ser was found in form 1 and Pro in form 2. The presence of Ser at position 186 introduces a consensus sequence for a N-glycosylation site (Asn-X-Ser/Thr). By removing N-linked sugars with N-glycanase, it could be demonstrated that the difference between the two forms of HRG is caused by an extra carbohydrate group at Asn 184 in form 1.

Amino Acid Sequence↗
PubMed1994

Interactions between collagen-binding stress protein HSP47 and collagen. Analysis of kinetic parameters by surface plasmon resonance biosensor.

A 47-kDa heat shock protein (HSP47) is a collagen-binding stress protein which is localized in the endoplasmic reticulum (ER) of collagen-secreting cells. Recent studies have shown that HSP47 transiently binds to newly synthesized procollagens and that conformationally abnormal procollagen is also bound by HSP47 for a much longer time in the ER (Nakai, A., Satoh, M., Hirayoshi, K., and Nagata, K. (1992) J. Cell Biol. 117, 903-914). HSP47 is thus suggested to have a collagen-specific molecular chaperone-like function. In this report, we analyzed the interaction of HSP47 and types I to V collagen using BIAcore system, an optical biosensor based on the principles of surface plasmon resonance. Types I-V collagen were purified from porcine skin, porcine articular cartilage, bovine lens capsule, and porcine placenta and immobilized on sensorchips of the BIAcore system at a surface concentration of 10-15 ng/mm2. Purified recombinant mouse HSP47 (rmHSP47) expressed in Escherichia coli was passed over the sensorchips at a flow rate of 2 microliters/min and binding curves of rmHSP47 to collagens were monitored. Using this approach, accurate association and dissociation rate constants were determined in addition to dissociation constants. rmHSP47 was found to bind to types I-V collagen with similar dissociation constants of the order of 10(-7) M. This relatively low dissociation constant resulted from the rapid dissociation rate constant (kdiss > 10(-2) s-1) and considerably high (kass approximately 2 x 10(4) M-1 s-1) association rate constant. These kinetic parameters may reflect a transient interaction between HSP47 and procollagen in vivo.

Amino Acid Sequence↗
PubMed1994

Comparative analysis of Igf-2/H19 imprinted domain: identification of a highly conserved intergenic DNase I hypersensitive region.

The closely linked, reciprocally imprinted mouse genes, insulin-like growth factor II (Igf-2) and H19, provide a significant paradigm for studies of the mechanism of parental imprinting. Most studies have focused on regions within and proximate to the genes, but an analysis of the whole region is essential to unravel how expression of these genes is controlled. A comparative long-range analysis of a 130-kb genomic region containing both genes was therefore carried out using material from normal and chromosome 7 maternal uniparental disomic embryos. We examined DNA methylation, chromatin structure assessed by hypersensitivity to DNase I, and regions that show strong conservation among mammalian species. The critical boundaries of differential DNA methylation and DNase I hypersensitivity are apparently confined within and proximate to the Igf-2 and H19 genes. However, we have identified a novel intergenic region that is conserved in mammals, GC-rich, and unmethylated in embryos and contains major DNase I hypersensitive sites.

Animals↗