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排序方式: 共有472条查询结果,搜索用时 187 毫秒
1.
K Imaida C Furihata M Tatematsu C H Yoon F Furukawa C Uneyama M Takahashi N Ito Y Hayashi 《Toxicologic pathology》1991,19(3):230-236
Pepsinogens are acid protease enzymes of pepsin usually found in gastric mucosa. In the present study, we demonstrated the presence of pepsinogen isozymes in male Syrian golden hamster lung tissues by a combined immunohistochemical and biochemical approach. Immunohistochemically, using rat pepsinogen 1 antibody, pepsinogen positive cells were observed mainly in the epithelia of the terminal bronchioles. They demonstrated morphological features of Clara cells. The pepsinogen isozyme pattern of lung tissue determined by polyacrylamide gel electrophoresis was similar to that of stomach mucosa. Treatment of hamsters with polychlorinated biphenyls at a dose of 500 mg/kg body weight ip caused a 2.8-fold increase in pepsinogen content (p less than 0.01) as well as increase in numbers of pepsinogen positive cells in the lung. 相似文献
2.
Transient induction of single GST-P positive hepatocytes by DEN 总被引:12,自引:3,他引:9
Satoh Kimihiko; Hatayama Ichiro; Tateoka Noboru; Tamai Katsuto; Shimizu Toshio; Tatematsu Masae; Ito Nobuyuki; Sato Kiyomi 《Carcinogenesis》1989,10(11):2107-2111
The single cells positive for placental glutathione S-transferase(GST-P), detectable in livers of rats soon after treatment withhepatocarcinogens, are possible initiated cells,the hypothesis tested in the present series of experiments.No low dose threshold was observed in male Sprague-Dawley ratsat different single doses of diethylnitrosamine (DEM) althougha plateau was reached between 160 and 200 mg/kg body weight.At the latter single dose 12 400 positive cells/cm3 were observedimmunohistochemically in rat livers after one week, the numbersthen decreasing to week 8 and thereafter rising again. In thenumbers then decreasing to week 8 and thereafter rising again.In the early stages single cells predominated but with timea gradual increase in mini-foci and larger lesions became evident.Application of selection pressure (feeding of diet containing0.02% 2-AAF plus partial hepatectomy) to rats 224 weeksafter single DEN-treatment resulted in the formation of largefoci positive for GST-P, especially in the early stages, thegrowth response being less pronounced with time. The numberof foci, on the other hand. was correlated with the number offoci, on the other hand, was correlated with the number ofsingle cells/mini-foci detected inhepatectomy tissue of thesame individuals. These results suggest that the early GST-Ppositive populations could be the precursor for preneoplasticfoci and nodules. 相似文献
3.
The dose-dependent effects of three hepatocarcinogens were investigated by measuring the number and area of glutathione S-transferase placental form (GST-P)-positive foci and nodules appearing in the liver under short-term conditions (Experiment I) and evaluating the incidence of hepatocellular carcinoma after long-term chronic administration (Experiment II). For these purposes, three different doses of 2-acetylaminofluorene (2-AAF), 3'-methyl-4-dimethy-laminoazobenzene (3'-Me-DAB), and DL-ethionine (ethionine) were given to male F344 rats for 6 weeks after a single injection of diethylnitrosamine (DENA) in Experiment I or for 104 weeks without initiation by DENA in Experiment II. In Experiment I, the induction of GST-P-positive foci and nodules by 2-AAF and 3'-Me-DAB was clearly dose-dependent. In contrast, ethionine showed enhancing effects inducing GST-P-positive foci and nodules only in groups given the highest dose level. Similarly, in Experiment II, induction of hepatocellular carcinomas by 2-AAF and 3'-Me-DAB was clearly dose-dependent, whereas liver neoplasms were only induced by the highest dose level of ethionine. These results indicate that degree of induction of GST-P positive foci and nodules in a short-term in vivo test for liver carcinogens corresponds with the incidences of hepatocellular carcinomas revealed in a long-term in vivo assay. 相似文献
4.
S. Yamamoto T. Masui H. Inoue Masae Tatematsu S. Fukushima S. Yonezawa M. Ichinose K. Miki 《Virchows Archiv : an international journal of pathology》1996,427(6):589-594
Expression of rat urinary bladder cathepsin E in benign papillomatosis induced by uracil and various stages of N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced carcinogenesis was investigated immunohistochemically. Seven-week-old, male F344/DuCrj rats were used. In the normal urothelium of control rats, cathepsin E stained in all layers of cells, although in umbrella cells and some basal cells the reaction was relatively weak. In rats given a diet containing 3% uracil for 5 weeks immunoreactivity of cathepsin E in uracil-induced papillomatosis was consistently homogeneous in all layers, but weaker than in normal urothelium. In rats given 0.05% BBN in drinking water for 12 weeks and subsequently maintained without treatment for 48 weeks cells with little cathepsin E, never observed in normal urothelium, appeared at 5 weeks above the basement membrane in the earliest stage of BBN-induced urinary bladder cancer (simple hyperplasia). Throughout the neoplastic process, groups of cells with a little cathepsin E were randomly distributed, with expression in the urothelium being markedly unstable. Almost all areas of squamous cell proliferation in TCC were negative for cathepsin E. Instability of cathepsin E expression in rat urothelium therefore appears characteristic for carcinogenesis and offers the possibility of using this feature as an early biomarker for urinary bladder carcinogenesis. 相似文献
5.
Reduction of cell proliferative activities of gastric stump adenomatous hyperplasias after bile reflux diversion in rats 总被引:4,自引:1,他引:3
Imai Toshio; Kobayasi Shoiti; Rodrigues Maria Aparecida Marchesan; Camargo Joao Lauro Viana de; Ogawa Kumiko; Iwata Hitoshi; Tatematsu Masae 《Carcinogenesis》1993,14(9):1765-1769
Previously we reported the majority of lesions induced by bilereflux, in the absence of chemical carcinogens, in the rat remnantstomach to consist primarily of gastric type and secondarilyof intestinal type cells, and that they are reversible afterdiversion of bile reflux. The present study was designed toevaluate changes in proliferative activities in cells of eachtype under these conditions. The frequency of adenomatous hyperplasia(AH) induced in the gastric stump mucosa by duodenal contentreflux after Billroth II partial gastrectomy (BII) increaseduntil the 54th week of the experiment. Roux-en-Y (RY) surgicalprocedure which prevents duodenal reflux performed at the 24thor 36th week after BII led to a decrease in AH. Cell contentof the lesions was analyzed using routine H&E staining,immunohistochemical staining for pepsinogen isoenzyme 1 andhistochemical procedures for mucins (paradoxical concanavalinA, galactose oxidase Schiff and sialidase galactose oxidaseSchiff reactions) and proliferation in each compartment evaluatedby an immunohistochemical method using bromodeoxyuridine (BrdU)and a monoclonal antibody against BrdU. At the 54th week thenumber of BrdU-labeled cells per normal pyloric column was significantly(P < 0.05) increased to 10.63/pit after the BII operation,while it diminished to 5.23/pit after RY diversion, this beingthe same level as with the RY procedure alone. AH maintaineda high rate of BrdU incorporation at 12.7% after BII operation,which was also significantly reduced (P < 0.01) to 7.0% bythe RY surgery. The intestinal type cell showed highest (22.2%),the surface mucous type cell showed the next (16.5%) and thepyloric gland type cell showed lowest (5.2%) BrdU labeling indicesafter BII operation. All the cell types in AH showed similarproportional decreases in BrdU incorporation after RY diversion.Thus surgical intervention reverses the cell proliferation causedby bile reflux in the gastric stump. 相似文献
6.
Redifferentiation as a basis for remodeling of carcinogen-induced hepatocyte nodules to normal appearing liver 总被引:12,自引:0,他引:12
A system is described for the detailed study of the remodeling of hepatic nodules that appear regularly during liver carcinogenesis with chemicals. With the use of the resistant hepatocyte model and by focusing on the caudate lobe, it has been possible to label with [3H]thymidine all the hepatocytes in hepatocyte nodules without any significant degree of labeling of the surrounding hepatocytes. Through such a model, the persistence of the label, in relation to the organization and appearance of the hepatocytes in the nodules, has been followed for 26 weeks. Nodules do not "disappear" to any significant degree by regression or by replacement with hepatocytes from the surrounding liver. Rather, nodule hepatocytes undergo differentiation to an adult liver phenotype. Thus, differentiation ("redifferentiation") of a carcinogen-induced altered hepatocyte population is seen regularly during carcinogenesis despite the irreversible nature of some of the changes induced by a chemical carcinogen during initiation. 相似文献
7.
Genetic instability and p53 mutations in metastatic foci of mouse urinary bladder carcinomas induced by N-butyl-N-(4- hydroxybutyl)nitrosamine 总被引:2,自引:0,他引:2
Yamamoto S; Chen T; Murai T; Mori S; Morimura K; Oohara T; Makino S; Tatematsu M; Wanibuchi H; Fukushima S 《Carcinogenesis》1997,18(10):1877-1882
In a variety of human malignancies, alteration of the p53 tumour suppressor
gene is known as a significant indicator of late progression events
including invasion and metastasis, with a possible close relationship to
genetic instability. Mutational analysis of the p53 and H-ras genes was
performed for 10 pairs of N-butyl-N-(4- hydroxybutyl)nitrosamine-induced
invasive mouse urinary bladder carcinomas and metastatic foci. p53
Mutations were found in nine of 10 (90%) primary carcinomas and seven of 10
(70%) metastatic foci. A total of eight p53 mutations in primary carcinomas
were common in metastatic foci in six pairs. Additional p53 or H-ras
mutations which were not identified in the primary carcinomas were found in
three metastatic foci. Evaluation of the allelic distribution of the p53
mutations using RT-PCR, PCR and subcloning, further indicated possible
intra-tumour genomic heterogeneity or excess copy numbers of the p53 gene
due to genetic instability. Overall, p53 alterations were frequent in mouse
urinary bladder carcinomas demonstrating progression. The results suggest
that genetic instability might underlie generation of additional genetic
alterations in this animal model.
相似文献
8.
Phenotypic shift in human differentiated gastric cancers from gastric to intestinal epithelial cell type during disease progression 总被引:3,自引:1,他引:3
Akemi Yoshikawa Ken-ichi Inada Takasuke Yamachika Nobuyuki Shimizu Michio Kaminishi Masae Tatematsu 《Gastric cancer》1998,1(2):134-141
Background. The phenotypic expression of tumor cells is widely thought to resemble that of the tissue of origin. In the present study,
to assess phenotypic changes that occur with disease progression, we investigated human differentiated gastric cancers at
different depths of invasion for component cancer cell types.
Methods. Using a combined mucin histochemical and immunohistochemical approach, we classified surgical specimens of 301 differentiated
gastric cancers into three types: gastric epithelial cell (G) type, intestinal epithelial cell (I) type and mixed gastric
and intestinal (GI) type, according to the phenotypic differentiation of the component cancer cells. The relation between
the phenotypic type of cancer and their depth of invasion was evaluated.
Results. The proportion of G type cancers was 41.4% in early (tumor invasion of mucosa or submucosa) cases, decreasing to 22.2% in
advanced (tumor invasion of muscularis propia or deeper) cases, whereas the proportion of I type cancers increased with progressive
disease from 23.5% to 31.1% (P < 0.01). Cancers invading the subserosa or deeper included more I type cases and fewer G type than cancers limited to the
mucosa (P < 0.01). In most cases of each phenotypic type, intestinal metaplasia was recognized in the surrounding background mucosa,
but no clear relation was shown between the phenotype of cancers and the degree of intestinal metaplasia in the background
mucosa, suggesting that intestinal metaplasia is not always a preneoplastic lesion.
Conclusions. A phenotypic shift from G to I type expression was observed with the progression of human differentiated gastric cancers.
Intestinalization may occur independently in cancerous and noncancerous gastric mucosa.
Received for publication on May 1, 1998; accepted on Oct. 22, 1998 相似文献
9.
Matsuda H Hayashi K Wakino S Kubota E Honda M Tokuyama H Takamatsu I Tatematsu S Saruta T 《Hypertension》2004,43(3):603-609
Although the angiotensin-converting enzyme (ACE) inhibitor-induced bradykinin enhances nitric oxide (NO) release, bradykinin may also stimulate the production of an additional vasodilator, endothelium-derived hyperpolarizing factor (EDHF). This study examined the role of EDHF in mediating the NO-independent action of ACE inhibitors in canine renal microcirculation in vivo. We used intravital CCD camera videomicroscopy that allowed direct visualization of renal microcirculation in superficial and juxtamedullary nephrons in an in vivo, in situ, and relatively intact setting. In the presence of E4177 (an angiotensin receptor blocker), cilazaprilat (30 microg/kg) had no effect on diameter of superficial afferent arterioles (Aff), but it increased renal contents of bradykinin and nitrate plus nitrite, and it elicited dilation of juxtamedullary Aff (from 24.0+/-0.2 to 28.2+/-0.8 microm), juxtamedullary efferent arterioles (Eff) (from 24.2+/-0.2 to 28.0+/-0.8 microm), and superficial Eff (from 18.2+/-0.2 to 19.7+/-0.2 microm). These changes in diameters were prevented by N(alpha)-adamantaneacetyl-d-Arg-[Hyp(3),Thi(5,8),D-Phe(7)]bradykinin, a bradykinin receptor antagonist. The pretreatment with nitro-l-arginine methylester (l-NAME) plus E4177 eliminated the dilator response of juxtamedullary/superficial Eff and the increase in renal nitrate plus nitrite levels induced by cilazaprilat. In contrast, in the presence of E4177+l-NAME, cilazaprilat still caused 8%+/-3% dilation of juxtamedullary Aff, which was completely eliminated by proadifen, a cytochrome-P450 and K(Ca) channel blocker. Collectively, the ACE inhibitor exerts multiple vasodilator mechanisms, including the inhibition of angiotensin II formation; blockade of angiotensin II activity appears to be a dominant mechanism in superficial Aff, whereas the bradykinin-induced NO acts on superficial Eff and juxtamedullary Aff/Eff. Furthermore, a putative EDHF is an additional mechanism for the ACE inhibitor-induced vasodilation of juxtamedullary Aff in vivo. 相似文献
10.
Tetsuya Tsukamoto Takeshi Toyoda Tsutomu Mizoshita Masae Tatematsu 《Seminars in immunopathology》2013,35(2):177-190
Helicobacter pylori infection is an important factor for gastric carcinogenesis in human. In carcinogen-treated Mongolian gerbils, H. pylori infection enhances stomach carcinogenesis, while infection alone induced severe hyperplasia called heterotopic proliferative glands. A high-salt diet or early acquisition of the bacteria exacerbates inflammation and carcinogenesis. Oxygen radical scavengers or anti-inflammatory chemicals as well as eradication of H. pylori are effective to prevent carcinogenesis. H. pylori-associated inflammation induces intestinal metaplasia and intestinalization of stomach cancers independently. It is necessary to control cancer development not only in H. pylori-positive cases but also in H. pylori-negative metaplastic gastritis. 相似文献