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T Shirai

Publications and source records attributed to T Shirai.

At least 163 records · Page 9Linked to original sources

[A 73-year-old woman with familial Parkinson's disease].

We report a 73-year-old Japanese woman with familial Parkinson's disease. The patient was well until her 67 years of the age, when she noted rest tremor in her right hand. Soon after her gait became short stepped. She visited our clinic on October 6, 1992 when she was 68 years old. She was alert and well oriented without dementia. She showed masked face, small voice, small stepped gait, retropulsion, resting tremor in her right hand, rigidity in the neck, and bradykinesia. She was treated with 400 mg/day of levodopa-carbidopa, which improved her symptoms, however, she developed wearing off phenomenon 3 years after the initiation of levodopa treatment. On August 26, 1998, she developed abdominal pain, diarrhea, and vomiting. She was admitted to another hospital, where abdominal plain x-ray revealed an evidence of intestinal obstruction (ileus). She was treated with nasogastric suction and intravenous fluid. Her condition did not improve and she was transferred to our hospital on August 29, 1998. Her family history revealed no consanguineous marriage. She had two elder brothers and three elder sisters. One of her brothers had been diagnosed as Parkinson's disease. Her husband also suffered from Parkinson's disease, however, her parents apparently did not have Parkinson's disease. On admission, she appeared to be drowsy. Her blood pressure was 102/70 mmHg, body temperature 36.2 degrees C. The lungs were clear and no cardiac murmur was present. Abdomen was flat and bowel sound was audible. No abnormal mass was palpable. Neurologic examination revealed mild consciousness disturbance, masked face, and small voice. No motor paralysis was noted. Muscle tone was hypotonic. No abnormal involuntary movement was noted. Abnormal laboratory findings on admission were as follows; WBC 11,300/microliter, amylase 1,373 IU/l, CK 446 IU/l, BUN 50 mg/dl, creatinine 1.17 mg/dl, CRP 22.7 mg/ dl, Na 134 mEq/l, K 3.1 mEq/l, and Cl 81 mEq/l. A chest x-ray film revealed pneumonic shadows in both lower lung fields. She was treated by nasointestinal suction, intravenous fluids, and chemotherapy for her infection. Her BP started to drop on September 2 and she developed cardiac arrest on the same day. She was discussed in a neurological CPC. The chief discussant arrived at the conclusion that the patient had a form of autosomal dominant familial Parkinson's disease. As parents did not have Parkinson's disease, some of the participants raised the possibility of autosomal recessive inheritance. But the age of onset was too late for autosomal recessive inheritance. Majority thought that the mode of inheritance was autosomal dominant with low penetrance. alpha-Synuclein mutation causes an autosomal dominant familial Parkinson's disease, but this type is very rare in non-Greek populations and the penetrance is high. Chromosome 2-linked autosomal dominant familial Parkinson's disease shows low penetrance. There are many other autosomal dominant forms of familial Parkinson's disease linked to yet unknown chromosome loci. Majority thought that this patient also had a form of Lewy-body positive autosomal dominant familial Parkinson's disease of unknown chromosome locus. Post mortem examination revealed ischemic intestinal lesion with strangulation. This was thought to be the cause of her death. In the central nervous system, the brain appeared to be normal by inspection. In the coronal sections, the substantia nigra and the locus coeruleus showed marked depigmentation. Histologic examination revealed marked neuronal loss and Lewy body formation in the remaining neurons. Pathologic examination was consistent with Parkinson's disease. Mutational analysis for the parkin gene was negative.

Aged↗

Use of polyclonal antibodies against carcinogen-DNA adducts in analysis of carcinogenesis.

Polyclonal antibodies against 3,2'-dimethyl-4-aminobiphenyl (DMAB)- and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-DNA adducts were raised for their immunohistochemical demonstration in paraffin-embedded sections. Both carcinogens target multiorgans in rats with colon, mammary glands and prostate as common tumor sites. PhIP is particularly important because it is a cooked food-derived carcinogen to which man is exposed on a daily bases. Dose-related nuclear staining in various tissue of rats was observed 24 h after single applications of both carcinogens but no observable decrease in staining intensity was evident in most organs by 168 h. Staining specificity in terms of sites of tumor development was lacking. However, in target organs, semiquantitative data on adduct formation correlated with alteration in tumor response by modifying factor(s). Furthermore, human prostate tissue implanted into nude mice showed positive staining. Thus, the antibodies can be applied as tools to clarify tissue or cell-specific carcinogenesis, carcinogen-exposure levels and metabolic activation in various species, including man after tissue transplantation.

Aminobiphenyl Compounds↗

Susceptibility alleles for aberrant B-1 cell proliferation involved in spontaneously occurring B-cell chronic lymphocytic leukemia in a model of New Zealand white mice.

B-cell chronic lymphocytic leukemia (B-CLL) and autoimmune disease are a related event, and genetic factors are linked to both diseases. As B-CLL is mainly of B-1 cell type that participates in autoantibody production, genetically-determined regulatory abnormalities in proliferation and/or differentiation of B-1 cells may determine their fate. We earlier found that, in H-2-congenic (NZB x NZW) F1 mice, while H-2(d/z) heterozygosity predisposes to autoimmune disease, H-2(z/z) homozygosity predisposes to B-CLL. Studies also suggested the involvement of non-H-2-linked NZW allele(s) in leukemogenesis. Using H-2-congenic NZW and B10 mouse strains, their F1 and backcross progeny, we have now identified three major NZW susceptibility loci for abnormal proliferation of B-1 cells, which form the basis of leukemogenesis; one H-2-linked locus on chromosome 17 and the other two non-H-2-linked loci, each on chromosome 13 and chromosome 17. Each susceptibility allele functioned independently, in an incomplete dominant fashion, the sum of effects determining the extent of aberrant B-1 cell frequencies. The development of leukemia was associated with age-related increase in B-1 cell frequencies in the blood. Thus, these alleles probably predispose B-1 cells to accumulate genetic alterations, giving rise to B-CLL. Potentially important candidate genes and correlation of the findings with autoimmune disease are discussed.

Animals↗

Optimal myocardial preconditioning in a human model of ischemia and reperfusion.

BACKGROUND: Adenosine (ADE) may mediate the protective effects of preconditioning (PC). However, human data are lacking, and the optimal method of ADE administration and the mechanism of protection remain unresolved. METHODS AND RESULTS: We have developed a model of simulated "ischemia" (I) and "reperfusion" (R) in quiescent human ventricular cardiomyocytes. Cellular injury and metabolic parameters were assessed after various interventions: Cells were preconditioned with anoxia (PC0), hypoxia (PC16), anoxic supernatant (SUP0), or hypoxic supernatant (SUP16) with or without the ADE receptor antagonist (SPT) or ADE deaminase (ADA). ADE was applied before, during, or after I or continuously with and without SPT. Cells were treated with the PKC agonist PMA. PC cells were incubated with the protein kinase-C (PKC) antagonist Calphostin-C (Cal-C). PKC translocation and PKC activity were assessed. PC0 was most protective. Protection was transferable via SUP0, which produced the highest concentrations of ADE. Protection was lost with SPT or ADA. Intracellular ATP fell after PC and prolonged I and R. Exogenous ADE was most protective when administered before I at 50 mumol. ADE during I was partially protective. No additional protection was provided with continuous ADE treatment. ADE prevented ATP degradation but increased lactate immediately after its administration. SPT abolished the protective effects of ADE. PMA conferred protection, which was abolished with Cal-C. ADE stimulated PKC translocation and PKC activity in the absence of SPT. CONCLUSIONS: Maximal I confers maximal PC. The degree of I is reflected in supernatant ADE concentrations. The initial ATP fall with PC may account for a lack of ATP preservation after I and R. ADE reproduces the protective effects of PC, preserves ATP, and increases lactate production, perhaps by stimulating glycolysis. Clinical trials of ADE administered during cardiac surgery are necessary to further define its beneficial effects in humans.

Adenosine↗

Characteristics of nonneoplastic human prostate tissue transplanted into nude mice.

BACKGROUND: Prostate tumors are characterized by sex hormone-associated growth and mesenchymal-epithelial interactions. This study was conducted to establish an ex vivo system where human prostate tissue could be maintained for a certain period under conditions resembling the in vivo situation in man to provide an experimental tool for investigation of prostate disease. METHODS: Human prostate tissues (peripheral zone and transition zone) obtained by total cystectomy were transplanted into the subcutis of male KSN nude mice for up to 24 weeks without exogenous hormonal manipulation. RESULTS: Transplants could be maintained, and although they showed several histological alterations, such as cystic dilation, basal-cell hyperplasia, and squamous-cell metaplasia, many retained a nearly normal appearance for the entire 24-week duration. Immunohistochemically, androgen receptors were strongly positive in the nuclei of glandular epithelial cells. Prostate-specific antigen (PSA) and prostatic acid phosphate (PAP) (both from DAKO, Glostrup, Denmark), were also expressed in the cytoplasm. The proportion of cells expressing proliferating cell nuclear antigen (PCNA) was not related to the period of transplantation and did not differ between the peripheral and transition zones. CONCLUSIONS: The results clearly demonstrate that human prostate tissues transplanted into nude mice can maintain their morphological and biological characteristics for up to 24 weeks. This provides a simple and useful tool for basic research into human prostate neoplasia.

Animals↗

Immunohistochemical demonstration of carcinogen-DNA adducts in tissues of rats given 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP): detection in paraffin-embedded sections and tissue distribution.

A polyclonal antibody against 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-DNA adducts was raised for their immunohistochemical demonstration in paraffin-embedded sections. Specificity of this antibody was confirmed by competitive ELISA. Positive signals were immunohistochemically detected in acetone-fixed but not in formalin- or ethanol-fixed sections from F344 rats treated by gavage with a single dose of PhIP at 37.5-300 mg/kg and killed at 1, 2, and 7 days thereafter. Dose-dependent positive staining was observed in almost all organs of both sexes, including the colon, prostate, and mammary gland but largely independent of the tumor response. Repair activity, judged by disappearance of adducts with time, differed according to the organ or cell type. One exception was hepatocytes, the liver incidentally being a nontarget organ. The results suggest that the generated antibody is applicable for detection of cells targeted by PhIP in paraffin-embedded sections and also for the investigation of the mechanisms of PhIP-carcinogenesis.

Administration, Oral↗

p53 gene mutations in rectal cancer associated with schistosomiasis japonica in Chinese patients.

Mutations in p53 tumor suppressor gene were examined in 44 Chinese patients with rectal cancer, including 22 cases with advanced schistosomiasis japonica and 22 cases without schistosomiasis. In schistosomal rectal cancer (SRC), 13 mutations were found in 10 cases, which included 11 base-pair substitutions and two deletions. Of 11 base substitutions, nine were transitions and two were transversions and seven of them were located at CpG dinucleotides. In non-schistosomal rectal cancer (NSRC), 13 mutations were found in nine cases, all of which were base-pair substitutions. Of 13 substitutions, 10 were transitions and three were transversions and three of them were located at CpG dinucleotides. The proportion of base-pair substitutions at CpG dinucleotides was higher in SRC patients than in NSRC patients, although this was not statistically significant (P = 0.054). Point mutation was frequent at codon 248 in SRC. A higher frequency of arginine missense mutations was observed in SRC than in NSRC. These observations suggest that the mutations in SRC are the result of genotoxic agents produced endogenously through the course of schistosomiasis japonica.

Aged↗

Strong promoting activity of phenylethyl isothiocyanate and benzyl isothiocyanate on urinary bladder carcinogenesis in F344 male rats.

Post-initiation effects of phenylethyl isothiocyanate (PEITC) and benzyl isothiocyanate (BITC) on hepatocarcinogenesis and urinary bladder carcinogenesis were examined in rats pretreated with diethylnitrosamine (DEN) and N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Groups of 21 rats received a single intraperitoneal injection of 200 mg/kg body weight of DEN. Starting 2 days thereafter, they were administered 0.05% BBN in the drinking water for 4 weeks. Three days after completion of the carcinogen treatment, they were placed on a diet containing PEITC or BITC at a dose of 0.1%, or a basal diet alone for 32 weeks and then killed for autopsy. Further groups of 6 rats each were similarly treated with PEITC, BITC or basal diet alone for 32 weeks without prior DEN and BBN exposure. In the liver, although the incidences of liver tumors were not significantly affected, the multiplicity of foci larger than 0.5 cm in diameter was slightly increased by PEITC. In the urinary bladder, the incidences of papillary or nodular (PN) hyperplasias and carcinomas were significantly elevated by PEITC or BITC after DEN and BBN initiation. In the groups without initiation, PN hyperplasia was found in all rats of both PEITC and BITC groups, along with papillomas and carcinomas in some animals. Tumors and PN hyperplasias in the groups treated with PEITC and BITC are characterized by downward growth. Our results thus showed PEITC and BITC to be strong promoters of urinary bladder carcinogenesis with some complete carcinogenic potential.

Animals↗

Design, construction, crystallization, and preliminary X-ray studies of a fine-tuning mutant (F133V) of module-substituted chimera hemoglobin.

A chimera betaalpha-subunit of human hemoglobin was crystallized into a carbonmonoxy form. The protein was assembled by substituting the structural portion of a beta-subunit of hemoglobin (M4 module of the subunit) for its counterpart in the alpha-subunit. In order to overcome the inherent instability in the crystallization of the chimera subunit, a site-directed mutagenesis (F133V) technique was employed based on a computer model. The crystal was used for an X-ray diffraction study yielding a data set with a resolution of 2.5 A. The crystal belongs to the monoclinic space group P21, with cell dimensions of a = 62.9, b = 81.3, c = 55.1 A, and beta = 91.0 degrees . These dimensions are similar to the crystallographic parameters of the native beta-subunit tetramers in three different ligand states, one of which is a cyanide form that was also crystallized in this study.

Amino Acid Sequence↗

L-selectin-specific autoantibodies in murine lupus: possible involvement in abnormal homing and polarization of CD4+ T cell subsets.

One notable functional abnormality in murine and human systemic lupus erythematosus (SLE) is the defect in the production of IL-2 in association with the deficit in naive CD4+ T cells. The mechanism is unknown, but one idea is that naturally occurring autoantibodies with specificities to the naive CD4+ T cell subpopulation are related to this event. We selected hybridoma monoclonal autoantibodies from SLE-prone (New Zealand Black (NZB) x New Zealand White (NZW))F1 mice that reacted with restricted populations of CD4+ T cells. One of these, H32, was specific for L-selectin, as determined by 1) distribution of Ag H32 on lymphoid cells similar to Mel-14, an epitope of L-selectin; 2) shedding of 80-kDa molecules with epitope H32 from the surface of lymph node cells coincidentally with Mel-14, when stimulated with phorbol ester; 3) cross-inhibitory activities on Ag binding between H32 and Mel-14; and 4) reactivity of H32 with recombinant mouse L-selectin. Pretreatment of 51Cr-labeled lymphocytes from BALB/c mice with H32 significantly inhibited their homing to lymph nodes in vivo. The BALB/c splenic H32+ CD4+ T cell subset produced few cytokines except IL-2, thus corresponding to naive ThP-type cells. This subset was markedly selectively depleted in aged (NZB x NZW)F1 mice. There was an age-associated increase in frequencies and titers of anti-L-selectin autoantibodies in sera from (NZB x NZW)F1 mice. Thus, abnormalities of naive CD4+ T cell subset, including IL-2 production in subjects with SLE, are at least partly attributed to the generation of autoantibodies to L-selectin.

Aging↗

A subset of CD4+ T cells expressing early activation antigen CD69 in murine lupus: possible abnormal regulatory role for cytokine imbalance.

Systemic lupus erythematosus (SLE), which spontaneously develops in (NZB (New Zealand Black) x NZW (New Zealand White)) F1 mice, is strictly dependent on CD4+ T cells. We found that in these mice with overt SLE, CD4+ T cells expressing CD69 molecules, an early activation Ag, are dramatically increased in peripheral lymphoid tissues and inflammatory infiltrates in the kidney and lung, but not in peripheral blood, while CD8+ and NK1.1+ T cells were virtually CD69-. Various adhesion molecules, including LFA-1, ICAM-1, CD43, CD44, P-selectin, and E-selectin, were up-regulated. Analysis of the TCR repertoire showed no skewed TCR Vbeta usage. Studies on in vitro cytokine production of spleen cells on TCR cross-linking indicated that compared with findings in young mice, the aged mice showed severely impaired production of IL-2, IL-3, and IL-4, whereas the levels of IL-10 and IFN-gamma remained relatively intact. FACS-sorted CD69-CD4+ T cells from aged mice produced substantial amounts of these cytokines, including IL-2, IL-3, and IL-4, whereas CD69+CD4+ T cells were poor producers. Intriguingly, when cocultured, CD69+CD4+ T cells significantly inhibited the production of IL-2 by CD69-CD4+ T cells. IL-2 production by spleen cells from young mice was also markedly inhibited in the presence of CD69+CD4+ T cells obtained from aged mice. We propose that CD69+CD4+ T cells that are continuously activated by self peptides bound to MHC class II molecules in (NZB x NZW)F1 mice may be involved in the pathogenesis of SLE through abnormal regulatory effects on cytokine balance.

Age Factors↗

Relationship between CD44 expression and differentiation of human prostate adenocarcinomas.

It is well documented that CD44 plays an important role in tumor metastasis. We investigated whether there is a correlation between the expression of its isoforms in prostate cancer cells and patient prognosis using 72 cases with biopsy specimens. Immunohistochemistry demonstrated expression of CD44H (68.1%), v6 (36.1%) and v9 (68.1%) to be relatively more frequent than that of other isoforms. A positive correlation between CD44H expression and tumor differentiation was found but this did not extend to clinical staging or prognosis. Likewise, results for CD44v6 or v9 expression suggest that they may be useful markers for prostate adenocarcinoma differentiation but not prognosis.

Adenocarcinoma↗

Stage and organ dependent effects of 1-O-hexyl-2,3,5-trimethylhydroquinone, ascorbic acid derivatives, n-heptadecane-8-10-dione and phenylethyl isothiocyanate in a rat multiorgan carcinogenesis model.

The effects of 1-O-hexyl-2,3,5-trimethylhydroquinone (HTHQ), phenylethylisothiocyanate (PEITC), 3-O-ethylascorbic acid, 3-O-dodecylcarbomethylascorbic acid and n-heptadecane-8, 10-dione were analyzed in a rat multiorgan carcinogenesis model. Groups of 15 animals were given a single intraperitoneal (i.p.) injection of diethylnitrosamine and 4 i.p. injections of N-methylnitrosourea as well as N-butyl-N-(4-hydroxybutyl) nitrosamine in the drinking water during the first 2 weeks. Then 4 subcutaneous (s.c.) injections of dimethylhydrazine and 2,2'-dihydroxy-di-n-propylnitrosamine were given in the drinking water over the next 2 weeks for initiation. Test compounds were administered during the initiation or post-initiation periods. The dietary dose was 1% except for n-heptadecane-8, 10-dione and PEITC (0.1%). Complete autopsy was performed at the end of experimental week 28. All 5 compounds reduced the number of lung hyperplasia, particularly PEITC when given during the initiation period. In addition, HTHQ lowered the incidence of esophageal hyperplasia in the initiation period, and of small and large intestinal adenomas in the post-initiation period. However, it also enhanced the development of hyperplasia and papilloma in the forestomach and tongue. PEITC lowered the induction of esophageal hyperplasia, kidney atypical tubules and liver glutathione S-transferase placental form (GST-P)-positive foci when given during the initiation period but enhanced the development of liver GST-P positive foci and urinary bladder tumors in the post-initiation period. Moreover, it induced hyperplasia of the urinary bladder. Our results indicate minor adverse effects for HTHQ in the forestomach and tongue, and demonstrate that PEITC, which inhibits carcinogenesis at the initiation stage in several organs, also exhibits promotion potential in liver and urinary bladder in the post-initiation stage under the present experimental conditions.

Animals↗

Down-regulation of c-myc and bcl-2 gene expression in PU.1-induced apoptosis in murine erythroleukemia cells.

We found that over-expression of PU.1, a member of the ets family of transcription factors, induces apoptotic cell death along with differentiation of DMSO stimulation in murine erythroleukemia (MEL) cells. To elucidate the molecular mechanisms of apoptosis, cell-cycle distribution and expression of several genes encoding apoptosis-promoting and -inhibiting factors were analyzed during the process of PU.1-induced apoptosis. FACS analysis revealed that cells were accumulated in the G0/G1 phase of the cell cycle before apoptosis. Morphological analysis of PI-stained nuclei of the apoptotic cells sorted by a FACScan showed 22.6% in G0/G1, 35.8% in S and 8.5% in G2/M phase by fluorescent microscopy after cell sorting, suggesting that PU.1-induced apoptosis in MEL cells occurs in G0/G1 through S phases. Semi-quantitative RT-PCR revealed that expression of c-myc and bcl-2 genes was reduced during the apoptotic process, while expression of bax and bcl-X(L) genes was not changed. Expression of the p53 gene was reduced rather than enhanced, suggesting that PU.1-induced apoptosis in MEL cells is p53-independent. Apoptosis was inhibited by adding 30% serum in culture, while no reduction of c-myc and bcl-2 gene expression was observed. Forced expression of the c-myc, bcl-2 and bcl-X(L) genes protected MEL cells from apoptosis. Our results suggest that a reduction of at least 2 important apoptosis-inhibiting factors, c-Myc and Bcl-2, is involved in PU.1-induced apoptosis in MEL cells.

Animals↗

p16 gene overexpression in mouse bladder carcinomas.

Deletion of 9p21 has frequently been observed in human bladder carcinomas. A candidate target suppressor gene, p16, was recently identified within this deleted region. In this study, we therefore investigated the loss of heterozygosity (LOH) of the p16 gene which is located on mouse chromosome 4, as well as its expression in mouse bladder carcinomas. We also studied the effects of normal cell contamination on LOH analysis using xenografts in CD-1(ICR) nude mice from B6C3F1 bladder carcinomas. We could not detect any LOH at the p16 locus in the mouse primary bladder carcinomas and xenografts. Surprisingly, overexpression of p16 was found in all primary mouse bladder carcinomas. Using microsatellite polymorphisms, a distinction could be made between PCR products derived from B6C3F1 and CD-1(ICR) nude mice. It was thereby confirmed that effects of normal cell contamination on LOH analysis are negligible when only tumor tissue is carefully sampled. The results suggest that abnormalities of p16 expression may be involved in mouse bladder carcinogenesis, but that gene deletion is not involved.

Animals↗

Specific detection of phosphatidylinositol 3,4,5-trisphosphate binding proteins by the PIP3 analogue beads: an application for rapid purification of the PIP3 binding proteins.

Phosphatidylinositol (PI) 3-kinase is known as one of the key molecules involved in the various biological events such as vesicle trafficking, cytoskeletal rearrangements and cell survival. T clarify the molecular basis underlying these events, we have tried to identify the proteins that can interact with phosphatidylinositol 3,4,5-trisphosphate (PIP3), the lipid product of PI3-kinase. Using a new PIP3 analogue, PIP3-APB, we synthesized an affinity column for PIP3 binding proteins. This enabled us to purify and identify several PIP3 binding proteins such as Tec tyrosine kinase, Gap1m, and Akt, as the candidates for the downstream molecules of PI3-kinase. All of these proteins contain PH domains, possible binding sites for phospholipids. Studies with various deletion mutants of Tec or Gap1m revealed that their PH domains are indeed the binding sites for PIP3. These results demonstrate that this PIP3-analogue binds various PIP3 binding proteins with high specificity and may be useful to elucidate the downstream mechanisms of PI3-kinases-mediated signaling pathways.

Adaptor Proteins, Signal Transducing↗

Modification by 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP) of 3,2'-dimethyl-4-aminobiphenyl (DMAB)-induced rat pancreatic and intestinal tumorigenesis.

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) has been shown to induce marked atrophic changes of exocrine pancreas of rats when given at 400 ppm in diet. On the other hand, 3,2'-dimethyl-4-aminobiphenyl (DMAB) causes pancreatic acinar tumors. Both chemicals also induce intestinal tumors. In the present experiment, the possible promotional effects of PhIP on DMAB-induced carcinogenesis in the rat were investigated with particular attention given to the pancreas and intestine. After initiation with subcutaneous injections of DMAB (150 mg/kg b.w.) once a week for 3 weeks, PhIP was administered in the diet at doses of 200, 100, 25 and 0 ppm from weeks 5 to 40. In a dose-dependent manner, PhIP clearly increased the numbers of basophilic acinar foci and nodules while decreasing development of acidophilic lesions. The incidences of adenocarcinomas of the small intestine but not the colon demonstrated a tendency for an increase with the higher doses of PhIP. The results thus indicated that PhIP administration after DMAB treatment exerts two different effects on pancreatic acinar cell lesions, enhancing the growth of basophilic foci and suppressing that of their acidophilic counterparts. Any influence on alimentary canal tumorigenesis was limited to the small intestine.

Adenocarcinoma↗