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Biomedical subjects

K Dohi

Publications and source records attributed to K Dohi.

At least 19 recordsLinked to original sources
PubMed1992

Randomized adjuvant trial to evaluate the addition of tamoxifen and PSK to chemotherapy in patients with primary breast cancer. 5-Year results from the Nishi-Nippon Group of the Adjuvant Chemoendocrine Therapy for Breast Cancer Organization.

BACKGROUND: A randomized adjuvant trial was conducted from October 1982 to January 1985 to evaluate the addition of tamoxifen (TAM) to combination chemotherapy with perioperative mitomycin C (MMC) and ftorafur (FT) for patients with estrogen receptor (ER)-positive tumors and the addition of PSK, a biologic response modifier, to MMC+FT chemotherapy for patients with ER-negative tumors in operable Stage IIA, IIB, and IIIA cancer. The doses used were 20 mg of oral TAM daily, 600 mg of oral FT daily, and 3 g of oral PSK daily for 2 years. Intravenous MMC (13 mg/m2) was given on the day of operation. METHODS: A total of 967 patients were entered and randomized by stratification based on ER status and staging (1978 International Union Against Cancer [UICC] criteria at the time of trial execution). Of 967 patients, 914 (94.5%) were evaluable. At 5-year follow-up, significant prolonged overall survival (OS) and relapse-free survival (RFS) times were seen with the addition of TAM in patients with ER-positive and Stage IIIA T3N0 cancer (1987 UICC-American Joint Committee on Cancer [AJCC] criteria); however, no significant survival benefit from TAM was seen in patients with ER-positive and Stage IIA T2N1 cancer. There was no significant difference between regimens, with or without PSK, in patients with ER-negative disease. RESULTS: Results of subset analyses suggested a benefit from TAM in postmenopausal patients with ER-positive and Stage IIA T2N1 cancer and a benefit from PSK in patients with node-negative, ER-negative, and Stage IIA T2N1 cancer. CONCLUSIONS: The 5-year results of the current trial showed a survival advantage by the addition of TAM to chemotherapy in patients with ER-positive and Stage IIIA T3N0 cancer.

Adjuvants, Immunologic↗
PubMed1992

252Cf relative biological effectiveness and inheritable effect of fission neutrons in mouse liver tumorigenesis.

To determine the relative biological effectiveness of 252Cf fission neutrons versus 60Co gamma-rays for inducing liver tumorigenesis, C57BL/6NCrj x C3H/NCrj F1, hereafter called B6C3F1, mice were irradiated once either with 252Cf or 60Co and the tumorigenicity of the two types of radiation was studied. Individual groups of B6C3F1 mice (about 30 mice/group) were irradiated once with 252Cf at doses of 0, 3, 6, 12.5, 50, and 200 cGy for males and 0, 12.5, 50, and 200 cGy for females or with 60Co at doses of 0, 12.5, 50, and 200 cGy for both sexes. The groups were observed for 13 months after irradiation. The incidence of hepatic tumors in nonirradiated controls was 3.8% in males and 3.2% in females. 252Cf irradiation increased the incidence dose dependently in males and females, but less efficiently in females. The mean number and size of hepatic tumors were well correlated with tumor incidence. In contrast, 60Co was less efficient at inducing tumors. The relative biological effectiveness of 252Cf compared to 60Co was quite high in the low-dose range. Overall, the average relative biological effectiveness of 252Cf versus 60Co was 15.2 in males and 2.5 in females. In another experiment, 7-week-old male C3H mice, which are known to be carriers of hepatic tumorinogens, and that were the fathers of the B6C3F1 mice, were irradiated with 0, 50, and 200 cGy of 252Cf, and 2 weeks later they were mated with nonirradiated female C57BL mice. The control mice had nonirradiated fathers. The incidence of hepatic tumors in the offspring of irradiated fathers was 43% in males and 1.7% in females, whereas in the offspring of control mice with nonirradiated fathers the incidence was 3.2% in males and 3.3% in females. The multiplicity of the hepatic tumors was similar to the tumor incidence. Thus our results indicated a strong hepatocarcinogenic potential for 252Cf neutrons compared to 60Co gamma-rays, and that the cancer-prone genetic trait activated by 252Cf irradiation was inherited by first-generation offspring, especially in males.

Animals↗
PubMed1992

Unique association of p53 mutations with undifferentiated but not with differentiated carcinomas of the thyroid gland.

Thyroid neoplasms show a wide variety of lesions varying from slowly growing differentiated adenocarcinomas to rapidly proliferating undifferentiated carcinomas. There has been some histopathological evidence that the undifferentiated thyroid carcinomas are derived from differentiated carcinomas. Moreover, it is suspected that some genetic events might be associated with such changes. In the present study, mutations in the p53 gene were investigated by direct sequencing analysis after polymerase chain reaction amplification of exons 5 to 8, using paraffin-embedded primary tumors and cultured cells. No mutations in exons 5 to 8 were detected in 10 differentiated papillary adenocarcinomas, whereas 6 of 7 undifferentiated carcinomas were found to carry base substitution mutations. Sequencing analysis confirmed mutations at codons 135 (TGC----TGT), 141 (CCC----CCT), 178 (CAC----GAC), 213 (CGA----TGA), 248 (CGG----CAG, CGG----TGG), and 273 (CGT----TGT). The spectrum of mutations (G:C to A:T transitions in 7 of 8) might be a specific feature of the spontaneous cancers. The results strongly suggest that, in human thyroid glands, p53 mutations play a crucial role in the progression of differentiated carcinomas to undifferentiated ones.

Adenocarcinoma, Papillary↗
PubMed1992

Osteogenesis associated with bone gla protein gene expression in diffusion chambers by bone marrow cells with demineralized bone matrix.

Diffusion chambers with rat bone marrow cells and demineralized bone matrix (DBM) were implanted subcutaneously to syngeneic 8-week-old rats and were harvested every week 3-7 weeks after implantation, and histochemical examination, determination of alkaline phosphatase activity, total calcium and phosphorus, the bone-specific vitamin K-dependent gla-containing protein (BGP) content, and detection of BGP mRNA relative to mineralization were performed. Alkaline phosphatase in diffusion chamber implants reached the highest activity at 4 weeks and then decreased. Calcium and phosphorus deposits occurred at 4 weeks after implantation and were followed by marked increases until 7 weeks, which was comparable to the accumulation of BGP. The BGP gene within the diffusion chambers began to be expressed at 5 weeks, and its expression increased markedly at 7 weeks after implantation. At 4-5 weeks after implantation, new bone adjacent to the membrane filters and cartilage toward the center of the diffusion chamber were observed histochemically. Light microscopic and immunohistologic examinations of chambers with marrow cells and DBM revealed production of mineralized matrices, typical of bone characterized by the appearance of BGP and mineralized nodules. In contrast, bone marrow cells alone did not show extensive bone formation and yielded very low values for these biochemical parameters. The present experiments demonstrate the potential of bone marrow cells and DBM to produce not only cartilage formation but also membranous bone formation associated with increasing expression of BGP mRNA during the later stages of bone formation, as well as a marked accumulation of BGP.

Alkaline Phosphatase↗
PubMed1992

Arteriovenous malformation of the pancreas associated with hepatocellular carcinoma. A case report and review of the literature.

A case of pancreatic arteriovenous malformation (AVM) with hepatocellular carcinoma is reported. The patient, a 56-year-old Japanese man, was asymptomatic. The pancreatic lesion was found incidentally during an evaluation for hepatocellular carcinoma. Celiac arteriogram demonstrated tortuous feeding arteries, a racemose intrapancreatic stain, which disappeared before the venous phase, and early portal filling.

Arteriovenous Malformations↗
PubMed1992

Glomerular tuft ballooning in mitomycin-C-induced renal impairment.

Severe ballooning of the glomerular tufts was observed in a 65-year-old man who was treated with mitomycin C (MMC) and had typical MMC-induced renal lesions. He developed renal failure and severe anaemia 6 months after initiation of chemotherapy. Ballooned tufts were caused by enormous expansion of the sub-endothelial space simultaneously associated with mesangiolysis. Glomerular cysts, described in a variety of disorders including thrombotic microangiopathy and diabetes mellitus, are derived from cystically dilated and united capillary luminae secondary to mesangiolysis. The morphogenesis of this unusual lesion when induced by MMC differs from that of the glomerular cysts previously reported.

Aged↗
PubMed1992

Development of a flow-cytometric HLA-A locus mutation assay for human peripheral blood lymphocytes.

A flow-cytometric technique was developed to measure the frequency of variant lymphocytes lacking expression of HLA-A2 or A24 allele products among donors heterozygous for HLA-A2 or A24. It was found that the variant frequency of lymphocytes in peripheral blood was of the order of 10(-4) and increased with donor age. Molecular analyses of mutant clones revealed that about one-third were derived from somatic recombinations and that the remaining two-thirds did not show any alterations after Southern blotting analysis. In contrast, mutants obtained after in vitro X-ray mutagenesis study were found to be mostly derived from large chromosomal deletions. A small-scale study on atomic bomb survivors did not show a significant dose effect.

Adult↗
PubMed1992

Polymerase chain reaction--single-strand conformation polymorphism analysis of polymorphism in DPA1 and DPB1 genes: a simple, economical, and rapid method for histocompatibility testing.

A new technical trial was carried out to detect polymorphism in HLA-DP genes, based on the diversity in electrophoretic mobility of single-stranded DNA (single-strand conformation polymorphism, SSCP). Genomic DNAs from 31 cell lines homozygous for 2 and 14 different DPA1 and DPB1 alleles, respectively, and from peripheral blood cells of a normal individual homozygous for another DPB1 allele were subjected to polymerase chain reaction (PCR) to amplify the polymorphic exon 2 of DPA1 or DPB1 genes. The PCR samples were denatured by heating in the presence of formamide to obtain single-stranded DNA, electrophoresed in a neutral polyacrylamide gel, and visualized by silver staining. Allelic differences were detected by the distinctive electrophoretic pattern of each single strand, depending on the sequence-specific conformation. Fifteen DPB1 alleles showed 11 distinct electrophoretic patterns, leaving four allelic combinations not distinguished. These four allelic combinations could be further distinguished by using another couple of primers in PCR, with which a part of the exon was amplified, and by subsequent SSCP analysis. The use of four pairs of primers in PCR allowed for discrimination of all the 15 DPB1 alleles tested. Two allelic differences in exon 2 of DPA1 gene could be clearly demonstrated. In addition, putative new alleles of DPA1 and DPB1 genes were detected by SSCP analyses. The PCR-SSCP analysis is simple and rapid, requires neither radioactive materials nor restriction enzymes, and is expected to be a useful tool for investigating the fine HLA-matching required for clinical transplantation of organs.

Alleles↗
PubMed1992

Lack of evidence that a transplanted liver causes acute graft-versus-host disease in rats. A comparison of liver and spleen grafts.

In this study, we used rat transplant models to investigate whether--and, if so, to what extent--transplanted liver had the potential to incite graft-versus-host disease, compared with the disease induced by a spleen graft. Livers from PVG(RT1c) rats were transplanted orthotopically into (DAxPVG)F1 (RT1a/c) rats and vascularized spleen grafts from PVG rats were transplanted heterotopically into (DAxPVG)F1 recipients. The intensity of the GVH disease was assessed by the recipients' morbidity and mortality, recipient-type serum class I (RT1Aa) antigen titer, and histological examination. The recipients of spleen grafts died within 14 and 23 days of transplantation; all animals had lost body weight and showed typical GVH signs, such as ear erythema, diarrhea, and alopecia. However, all the recipients bearing liver grafts survived indefinitely and did not demonstrate weight loss or the typical symptoms associated with GVH disease. The skins, tongues, and intestines of the liver-grafted rats were virtually normal at histological examination, whereas the livers, salivary glands, and skins of spleen-grafted rats were infiltrated by immunoblasts. The recipient-type serum RT1Aa antigen titer increased progressively until death in the spleen graft but not the liver graft recipients. These results provide evidence that suggest that transplanted liver is less likely than transplanted spleen to initiate the GVH disease in rats.

Acute Disease↗
PubMed1992

A comparison of some simplified lactobionate preservation solutions with standard UW solution and Eurocollins solution for pancreas preservation.

Fifty-two rat pancreas transplants were performed to investigate which components of the UW solution were essential for successful pancreas preservation. LEW rats were used and the pancreata stored at 4 degrees C for 48 hr after flushing with commercial UW solution (ViaSpan, DuPont Pharmaceuticals) or a number of simplified solutions. Following storage the pancreata were transplanted into syngeneic recipient animals with streptozotocin-induced diabetes mellitus. Graft function was assessed by regular postoperative blood sugar measurements and a glucose tolerance test on the 14th postoperative day. With commercial UW solution, 4 of 9 recipients (44%) showed satisfactory graft function, while only one of 5 pancreata preserved using Eurocollins solution demonstrated satisfactory function. With solution A, in which hydroxyethyl starch and insulin were omitted from the standard UW solution, 3 of 7 recipients (43%) showed satisfactory function. Omission of glutathione, allopurinol, and adenosine from this solution (solution B) gave satisfactory function in 4 of 8 cases (50%). Substitution of raffinose in solution B with an equimolar concentration of glucose (solution C) resulted in acceptable function in 5 of 8 cases (62%). Increasing the raffinose concentration in solution B to 100 mM/L resulted in only 2 of 8 grafts (25%) with adequate function. By contrast, reversing the Na/K concentrations in solution A resulted in 100% (7/7) satisfactory graft function. We conclude that the rat pancreas can be successfully transplanted following 48-hr cold preservation using UW solution and some simplified versions, and that a substantially simplified lactobionate-based solution with a reversed sodium/potassium ratio improved survival.

Adenosine↗
PubMed1992

An examination of the effects of solutions containing histidine and lactobionate for heart, pancreas, and liver preservation in the rat.

Fifty-five rat pancreas transplants, 18 rat heart transplants, and 41 rat liver transplants were performed using standard UW solution, the new HL solution (HL-I), or a modified HL solution (HL-II). Storage times of 18 hr were used in the heart preservation experiments, 24 hr in the liver preservation experiments, and 48 or 72 hr in the pancreas preservation experiments. HL-I solution was superior to both HL-II and UW solution for heart preservation (1-week graft survival rates of 100% [7/7], 0% [0/5], and 50% [3/6], respectively). HL-I and HL-II were superior to UW for 24 hr liver preservation (1-week graft survival rates of 78% [11/14], 80% [8/10], and 29% [5/17], respectively). In contrast, HL-II was superior to both HL-I and UW solutions for pancreas preservation following both 48-hr preservation and 72-hr preservation. Satisfactory graft function was achieved in 100% (7/7), 40% (6/15), and 44.4% (4/9) of pancreases transplanted after 48 hr using HL-II, HL-I, and UW solutions, respectively, and in 50% (4/8), 0% (0/8), and 0% (0/8) following 72-hr preservation. Histidine- and lactobionate-containing solutions thus represent a further improvement in organ preservation by simple cold storage.

Adenosine↗
PubMed1992

A serine protease-inhibitory benzamidine derivative inhibits the growth of human colon carcinoma cells.

The inhibitory effect of a serine protease-inhibiting tetra-benzamidine derivative, TAPP-Br, on the cell growth of 8 human colon carcinoma cell lines was examined and the mechanism of the inhibition was analyzed. TAPP-Br inhibited the cell growth of all the colon carcinoma cell lines, and this effect was irreversible. The expression of mRNAs for nuclear oncogenes such as MYC, FOS and JUN was decreased by TAPP-Br after treatment for 3 h and the effect continued for 48 h. mRNA expression of epidermal growth factor receptor, transforming growth factor-beta and type IV collagenase was suppressed at 48 h after the initiation of TAPP-Br treatment, suggesting an indirect action of TAPP-Br. TAPP-Br decreased protein kinase C activity in the particulate fraction, whereas it increased the enzyme activity in the soluble fraction. These findings overall suggest that the serine protease inhibitor, TAPP-Br, might inhibit the cell growth of colon carcinoma cell lines through suppressing the expression of genes whose promoter contains a 12-O-tetradecanoylphorbol-13-acetate-responsive element or serum-responsive element.

Antineoplastic Agents↗
PubMed1992

Carcinogenicity of 1,2-dimethylhydrazine in colorectal tissue heterotopically transplanted into the glandular stomach of rats.

The present study was designed to examine the effect of the intestinal carcinogen 1,2-dimethylhydrazine (DMH) on grafted colorectal mucosa implanted into the glandular stomach of rats. Four groups were studied: Group 1 received the operation and DMH, Group 2 received the operation alone, Group 3 received DMH alone and Group 4 (controls) received only a sham operation. For Groups 1 and 2, about 8-mm diameter segments of colorectal tissue obtained from various sites in the large intestine of 8-week-old male F344 rats were isologously implanted into the fundic region of the stomachs of age-matched rats. DMH was injected at a dose of 20 mg/kg body weight i.m. per week for 20 weeks beginning 4 weeks after the operation. The animals were then observed for 8 months after the initial DMH treatment. In Group 1, adenocarcinomas developed in 41 of 60 successful implants (68%). Furthermore, poorly differentiated type tumors were observed in the grafts obtained from the rectum. This finding was contrary to that for intrinsic rectal tumors, all of which were well differentiated. The histochemical staining of mucin in the tissues from different sites of the large intestine revealed that sulfomucin, which normally exists essentially only in the intrinsic descending colon or rectum, was present in the grafts from the proximal ascending or ascending colon. No gastric tumors were observed in the control rats, which received either DMH or sham operations alone. Tumors in the intrinsic large intestine were observed only in rats that received DMH. These results indicate that colorectal mucosa implanted into the glandular stomach, like the intrinsic large intestine, is still sensitive to tumorigenesis caused by DMH.

1,2-Dimethylhydrazine↗
PubMed1992

Detection of cytomegalovirus in urine samples by an enzyme-linked immunosorbent assay using a monoclonal antibody against the viral 150-kilodalton protein.

McKeating et al. (J.A. McKeating, P.D. Griffiths, and J.E. Grundy, J. Gen. Virol. 68:785-792, 1987; J. A. McKeating, J. E. Grundy, Z. Varghese, and P. D. Griffiths, J. Med. Virol. 18:341-348, 1986; J. A. McKeating, S. Stagno, P. R. Stirk, and P. D. Griffiths, J. Med. Virol. 16:367-373, 1985) reported previously that beta 2 microglobulin inhibits the detection of human cytomegalovirus (CMV) in urine specimens by an enzyme-linked immunosorbent assay (ELISA) with a monoclonal antibody against the glycoprotein of CMV. They postulated that beta 2 microglobulin binds to the viral glycoproteins and masks the antigenic determinants. We developed here an ELISA method for the detection of CMV in urine by using a monoclonal antibody against the viral 150-kDa protein to capture the viral antigen. This assay detected CMV both in culture medium and in urine specifically at concentrations higher than 10(3) PFU/ml and quantitatively at concentrations higher than 10(4) PFU/ml. The sensitivity of the ELISA increased about 10-fold when peroxidase-labeled F(ab')2 from goat anti-human immunoglobulin G was used as a secondary detecting antibody in combination with concentration of the virus in urine samples by ultracentrifugation. The inhibition of ELISA by beta 2 microglobulin was not observed in this ELISA system. When 56 urine specimens from renal transplant recipients were examined for CMV antigens, the ELISA system had a sensitivity of 78% and a specificity of 97%. The positive and negative predictive values of the assay were 95 and 86%, respectively. Furthermore, CMV antigens in urine were quantitated by the assay during the course of typical CMV disease of renal transplant recipient. These results suggest strongly that the measurement of CMV antigens in urine by our rapid and quantitative ELISA system provides very useful data for the monitoring of CMV infections in renal transplant recipients and making decisions about therapy.

Antibodies, Monoclonal↗
PubMed1992

Induction of interleukin 6 synthesis in mouse glomeruli and cultured mesangial cells.

Interleukin 6 (IL-6) is an autocrine growth factor of cultured mesangial cells (MC) and intraglomerular IL-6 production is suggested to be closely associated with the pathogenesis of human mesangial proliferative glomerulonephritis (mesPGN). In this study, to elucidate the mechanisms regulating the intraglomerular production of IL-6, we examined what kinds of stimuli are significant in the induction of IL-6 synthesis in vitro and in vivo. Incubation of cultured mesangial cells with interleukin 1 (IL-1) or bacterial lipopolysaccharide (LPS) induced significant IL-6 production, and intravenous injection of IL-1 or LPS into normal BALB/c mice induced significant intraglomerular IL-6 mRNA expression. Furthermore, we indicated in this study that IL-6 mRNA expression was augmented in the glomeruli of mice with immune complex-mediated glomerulonephritis.

Animals↗
PubMed1992

A comparison study of rat pancreas preservation using perfluorochemical and fluorocarbon-emulsion as preservation medium.

We reported previously the successful 72-hour cold rat pancreas preservation by using Perfluorochemical (PFC). The present study is to determine whether Fluorocarbon (FC) emulsion is as effective as PFC for long-term rat pancreas preservation. Lewis rat pancreases were stored in FC emulsion (4 degrees C) saturated by continuous supply of oxygen:carbon dioxide (95%:5%) (Group I) or by 100% pure nitrogen (Group II), or in PFC (4 degrees C) saturated by continuous supply of oxygen:carbon dioxide (95%:5%) (Group III) or nitrogen (Group IV) for 24 h and 48 h. Heterotopic pancreas transplantation into isogeneic diabetic rats were performed following preservation. Functional graft success rates following 24 h and 48 h cold storage were 71% (5/7) and 0% (0/5) in Group I, 71% (5/7) and 0% (0/5) in Group II, 100% (5/5) and 80% (4/5) in Group III, and 80% (4/5) and 0% (0/5) in Group IV, respectively. These results showed that, as an artificial blood substitute, the PFC with simple oxygen bubbling for 48-hour preservation of rat pancreas was much effective than FC emulsion, but not effective when saturated with nitrogen. We concluded that the PFC with saturated oxygen can obtain long-term successful preservation of rat pancreas. The direct oxygenation of the graft tissues is thought to play an important role in organ preservation.

Animals↗