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31.
Jörg Wilting Cecilia Ebensperger Thomas S. Müller Haruhiko Koseki Johan Wallin Bodo Christ 《Anatomy and embryology》1995,192(3):221-227
The Pax-1 gene has been found to play an important role in the development of the vertebral column. The cervico-occipital transitional zone is a specialized region of the vertebral column, and malformations of this region have frequently been described in humans. The exact embryonic border between head and trunk is a matter of controversy. In order to determine a possible role of Pax-1 in the development of the cervico-occipital transitional zone we studied the expression of this gene in a series of quail embryos and murine fetuses with in situ hybridization and immunohistochemistry. Pax-1 is expressed in all somites of the embryo, including the first five occipital ones. During embryonic days 3–5 the gene is down-regulated in the caudal direction within the first five somites, whereas more caudally Pax-1 is strongly expressed in the cells of the perinotochordal tube. In 5-day-old quail embryos, the cartilaginous anlage of the basioccipital bone has developed and there is no more expression of Pax-1 in this region. The fusion of the dens axis with the body of the axis also coincides with switching off of the Pax-1 gene. More caudally, the gene is continuously expressed in the intervertebral discs of murine embryos and therefore seems to be important for the process of resegmentation. Quail embryos do not possess permanent intervertebral discs. Hyper- or hyposegmentation defects may be explained by an over- or under-expression of Pax-1 during development. We also reinvestigated the border between the head and trunk in chick embryos by performing homotopical grafting experiments of the 5th somite between chick and quail embryos. Grafted quail cells formed mainly the caudal end of the basioccipital bone. They were also located in the cranial half of the ventral atlantic arch, and only a few cells were found in the tip of the dens axis. 相似文献
32.
Claudia Schwab John C. Steele Haruhiko Akiyama Edith G. McGeer Patrick L. McGeer 《Acta neuropathologica》1995,90(3):287-298
The Chamorro population of the island of Guam is highly susceptible to a disease called lytico-bodig (LB), wich clinically resembles a mixture of amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD) and Alzheimer disease (AD). The disease is characterized by the widespread development of neurofibrillary tangles in the central nervous system. These tangles have an immuno-histochemical profile indistinguishable from that seen in AD. We studied by immunohistochemistry the occurrence of intracellular and extracellular neurofibrillary tangles in LB in the entorhinal cortex, hippocampus and substantia nigra using antibodies to tau protein and ubiquitin. We also studied the relationship of these tangles to amyloid precursor protein (APP) and its -amyloid fragment (BAP), using multiple antibodies to BAP and other APP sequences. In advanced cases of LB, the development of neurofibrillary tangles was far more severe than in advanced cases of AD. Virtually all neurons of CA-1 and the subiculum were lost and only ghost tangles remained. In areas dominated by such extracellular tangles, BAP deposits were frequently observed developing around the fibers of ghost tangles. In some cases, the deposits covered only a few of the fibers, but in others, they seemed to envelope the complete tangle. The deposits were thiolavin S and Congo red positive, indicating that the BAP was in a consolidated form. We describe these entities as tangle-associated amyloid deposits. Such BAP deposits have previously eeen described in some cases of AD, dementia pugilistica and LB. However, we found them in all cases of LB with dementia in the hippocampal-entorhinal areas and in most cases in the substantia nigra. They do not evolve from diffuse BAP deposits since they are remote from them, and they do not trap dystrophic neurites. The fact that extracellular tangle material can act as a nidus for BAP build-up in LB suggests that further consideration needs to be given to the ways in which extracellular BAP deposits are formed. 相似文献
33.
Immunolocalization of basic fibroblast growth factor during wound repair in rat retina after laser photocoagulation 总被引:3,自引:0,他引:3
Chikako Yamamoto Nahoko Ogata Xianjin Yi Kanji Takahashi Miki Miyashiro Haruhiko Yamada Masanobu Uyama Kouichi Matsuzaki 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(11):695-702
Background: Basic fibroblast growth factor (bFGF) stimulates the mitogenesis of various cells and plays a key role in wound repair. We studied the immunohistochemical localization of bFGF during wound repair in the rat retina after laser photocoagulation. Methods: Krypton laser photocoagulation was performed on the eyes of pigmented rats. The eyes were enucleated on days 1, 3, 7, 14 and 28 after the photocoagulation, and the immunohistochemical localization of bFGF was assessed. Two different monoclonal antibodies and one polyclonal antibody against bFGF as first antibodies were used. Results: Marked immunoreactivity for bFGF was found in the ganglion cell layer, and weak immunoreactivity for bFGF was found in the retinal pigment epithelial (RPE) cells of the normal adult rat retina. On day 3 after laser photocoagulation, the nuclei and cytoplasm of proliferating RPE cells at the center of the photocoagulated lesion showed intense bFGF immunoreactivity. The nuclei of RPE cells around the lesion showed intense bFGF immunoreactivity. Macrophages that migrated into the lesion showed positive staining for bFGF. These immunoreactivity decreased with time. Controls (0.05 M Tris-HCl buffer, normal serum, or these same antibodies preabsorbed with bFGF) did not show positive staining. Conclusion: The finding of an elevated expression of bFGF immunoreactivity in the photocoagulated lesion suggests that bFGF may play a role in wound repair in the rat retina after laser photocoagulation. 相似文献
34.
Akihiko Kimura Tomoji Uda Shoichi Nakashima Haruhiko Ikeda Seiji Yasuda Motoki Osawa Tsutomu Tsuji 《International journal of legal medicine》1993,106(1):1-4
Summary The erythrocyte band 3 (EPB3) variant, band 3 Memphis (EPB3*Memphis), was detected by immunoblotting with a monoclonal antibody to the 41 kDa cytoplasmic N-terminal domain of band 3 without protease treatment of erythrocytes. EPB3*Memphis was also detected by immunoblotting from 3-month-old bloodstains subjected to -chymotrypsin treatment. A population genetic study using this method indicated that the EPB3 variant would be useful for forensic work in Japan, since the frequency of this variant in Japanese (Wakayama prefecture) is relatively high (0.159). 相似文献
35.
Shigemi Onoue Takehito Katoh Yoshihisa Shibata Yasushi Mokuno Katsushi Yoshida Satoshi Kamiya Tetsuya Abe Kiyoshi Hiramatsu Minoru Esaki Haruhiko Chigira 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(2):121-124
We report a case of a long-term survivor with malignant melanoma of the anus who did not undergo radical surgery. A 71-year-old
woman who presented with anal bleeding and anal tumor underwent an excisional biopsy in September 1985. The biopsy specimen
was a lobulated, polypoid, pigmented mass 2 cm in diameter, that had been located on the anterior wall of the anus. A satellite
nodule 7 mm in diameter was found on the left wall of the anus at the level of the dentate line. Both tumors were histologically
diagnosed as malignant melanoma. The primary tumor was 6 mm thick. Melanoma cells were present microscopically at the cut
end of the rectum. Because of her history of ischemic heart disease, the patient rejected our recommendation that she undergo
radical surgery, and received 10 courses of carboplatin 20 mg intramuscularly and OK-432 10 K.E. (Klinische Einheit) intradermally
every week. A single, pigmented metastatic inguinal lymph node developed and was excised in June 1987. A recurrent tumor was
detected in the rectum in October 1992, so again we recommended radical surgery. The patient rejected radical surgery again,
and received 12 courses of carboplatin 10 mg intramuscularly every 2 weeks. She died of disease at home in July 1993 after
surviving for 7 years and 10 months. An autopsy was not performed. This case shows that local excision of the primary lesion
may be appropriate to preserve the quality of life of patients with early-stage malignant melanoma of the anus. 相似文献
36.
Induction of apoptosis in multi-drug resistant (MDR) human glioblastoma cells by SN-38, a metabolite of the camptothecin derivative CPT-11 总被引:5,自引:0,他引:5
Shouji Nakatsu S. Kondo Yasuko Kondo Dali Yin John W. Peterson Rami Kaakaji Tatsuo Morimura Haruhiko Kikuchi Juji Takeuchi Gene H. Barnett 《Cancer chemotherapy and pharmacology》1997,39(5):417-423
The overexpression of the multidrug resistance (mdr1) gene and its product, P-glycoprotein (P-gp), is thought to limit the successful chemotherapy of human tumors. Recent studies
demonstrate that SN-38, a metabolite of the camptothecin (CPT) derivative CPT-11, has antitumor effects on several tumors,
but the mechanisms responsible for its cytotoxicity remain unclear. We therefore determined whether SN-38 has cytotoxic effects
on MDR human glioblastoma GB-1 cells and non-MDR human glioblastoma U87-MG cells. Furthermore, we determined what role SN-38
plays in the induction of cytotoxicity in these tumor cells. In this study, we demonstrated that SN-38 had significantly stronger
antitumor effects on GB-1 and U-87MG cells than did CPT (P<0.01 and P<0.05, respectively). In addition, findings obtained using a DNA fragmentation assay, Hoechst 33258 staining, in situ end-labeling
and cell cycle analysis demonstrated that SN-38 induced apoptosis in these tumors. Our results suggest that SN-38 has a stronger
antitumor effect on malignant glioma cells regardless of MDR expression than does CPT, and therefore can be considered a new
chemotherapeutic agent potentially effective in the treatment of human primary or recurrent malignant gliomas resistant to
chemotherapy.
Received: 6 October 1995/Accepted 29 June 1996 相似文献
37.
Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum 总被引:1,自引:2,他引:1
Hiroyuki Uchida Hiroshi Ando Keiji Maruyama Hiroshi Kobayashi Hiroshi Toda Hiroshi Ogawa Takachika Ozawa Yasuhide Matsuda Haruhiko Sugimura Takashi Kanno Shozo Baba 《Cancer science》1998,89(3):299-306
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs. 相似文献
38.
Infrequent Mutations of the hOGG1 Gene, That Is Involved in the Excision of 8-Hydroxyguanine in Damaged DNA, in Human Gastric Cancer 总被引:4,自引:0,他引:4
Kazuya Shinmura Takashi Kohno Hiroshi Kasai Kenji Koda Haruhiko Sugimura Jun Yokota 《Cancer science》1998,89(8):825-828
DNA glycosylase, encoded by the hOGG1 gene, repairs 8-hydroxyguanine (oh8 Gua), which is an oxidatively damaged mutagenic base. To clarify whether the DNA repair activity of hOGG1 protein is involved in gastric carcinogenesis, we examined 9 gastric cancer cell lines and 35 primary gastric cancers for mutations and genetic polymorphisms of the hOGG1 gene by polymerase chain reaction-single strand conformation polymorphism analysis. A G-to-A transition was detected in a gastric cancer cell line, MKN1. This nucleotide change caused the conversion of the amino acid from Arg to His at codon 154, which is located in a domain highly conserved among human, mouse, and yeast OGG1 proteins. No mutation was detected in primary gastric cancers. We compared the distribution of the polymorphic alleles associated with enzymatic activity (hOGG1-Ser326 vs. hOGG1-Cys326 ) between 35 gastric cancer patients and 42 healthy individuals. Although the frequency of the Cys326 allele, associated with low enzymatic activity, in gastric cancer patients was a little higher than that in healthy individuals, the difference did not reach statistical significance. These results suggest that low hOGG1 activity due to mutations and genetic polymorphisms is involved in the development of only a small subset of gastric cancers. 相似文献
39.