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11.
Yoshitaka Hibino Ken-ichiro Hata Kunio Horie Shuhei Torii Minoru Ueda 《Journal of cranio-maxillo-facial surgery》1996,24(6):346-351
Numerous clinical reports have shown the utility of cultured epithelial grafting in the field of plastic and reconstructive surgery. Recently, freezing storage of the cultured epithelium has been tried and has successfully grafted after thawing. It is clinically convenient if it is possible for cultured epithelium to keep its normal structure and viability. However, few papers have described the structural changes in cultured epithelium after freezing storage. In the present study, the morphological changes and cell viability of cultured mucosal epithelial sheets after freezing were studied in comparison with cultured epidermal sheets. Furthermore, we discuss the effect of storage temperature and cryoprotectants.As a result, there were some structural changes such as vacuolar degeneration in the cultured mucosal sheets using dimethyl sulphoxide (DMSO) as a cryoprotectant. Such changes were more clearly observed at −80°C than at −196°C with DMSO. However, little morphological change was observed in both epithelial sheets cultured with glycerin. The cell viability analysed by flow cytometry showed that more than 62% of the cells kept their viability after freezing storage. These results suggest that the optimum conditions of freezing for cultured epithelium were −196°C storage by slow cooling methods with glycerin as a cryoprotectant. 相似文献
12.
Tomoko Yoshinari Yoshikazu Iwasawa Keiko Miura Ikuko S. Takahashi Takahiro Fukuroda Kunio Suzuki Akira Okura 《Cancer chemotherapy and pharmacology》1989,24(6):367-370
Summary BS compounds, a series of new dihydropyridines, successfully overcame multidrug resistance in P388/ADR cells in vitro. These agents synergistically potentiated the cytotoxicity of Adriamycin to P388/ADR cells at a concentration of 1–2 M, whereas they showed hardly any synergistic effect in the parental cell line (P388/S) at the same concentration. They inhibited the active drug efflux in P388/ADR cells as well as the binding of [G-3H]-vinblastine to membrane vesicles from P388/ADR, which was increased in resistant P388 cells as compared with parental cells. Besides, unlike the activity of clinically used calcium antagonists, the calcium antagonistic activity associated with BS compounds was very weak: their arterial relaxation activity was <21% of that of verapamil. These data suggest that BS compounds specifically overcome multidrug resistance without the serious hypotensive side effects that accompany the use of verapamil orother calcium antagonists. 相似文献
13.
S H Embury S J Scharf R K Saiki M A Gholson M Golbus N Arnheim H A Erlich 《The New England journal of medicine》1987,316(11):656-661
We have used a new method of DNA analysis for the rapid prenatal diagnosis of sickle cell anemia in two fetuses at risk for this disease. This method of detecting the sickle gene is a modification of standard restriction-enzyme techniques and requires only a small amount of DNA. The first step involves a 200,000-fold enzymatic amplification of the specific beta-globin DNA sequences that may carry the sickle mutation. This provides a sufficient quantity of DNA for the analysis. Next, a short radiolabeled synthetic DNA sequence homologous to normal beta A-globin gene sequences is hybridized to the amplified target sequences. The hybrid "duplexes" are then digested sequentially with two restriction endonucleases. The presence of beta A- or beta S-globin gene sequences in the amplified target DNA from the patient determines whether the beta A-hybridization probe anneals perfectly or with a single nucleotide mismatch. This difference affects the restriction-enzyme digestion of the DNA and the size of the resulting radiolabeled digestion products, which can be distinguished by electrophoresis followed by autoradiography. This method is sufficiently sensitive and rapid that the prenatal diagnosis of sickle cell anemia can be made on the same day that the fetal DNA is made available. It can also be applied to the diagnosis of hemoglobin C disease. 相似文献
14.
Yuzheng Wu MSc Kunio Doi Charles E. Metz Naoki Asada Maryellen L. Giger 《Journal of digital imaging》1993,6(2):117-125
Artificial neural networks are being investigated in the field of medical imaging as a means to facilitate pattern recognition and patient classification. In the work reported here, the effects of internal structure and the nature of input data on the performance of neural networks were investigated systematically using computer-simulated data. Network performance was evaluated quantitatively by means of receiver operating characteristic analysis and compared with the performance of an ideal statistical decision maker. We found that the relatively simple neural networks investigated in this study can perform at the level of an ideal decision maker. These simple networks were also found to learn accurately even when the training data are extremely unbalanced with respect to the prevalence of actually positive cases and to differentiate input data patterns by recognizing their unique characteristics. 相似文献
15.
Kiyoshi A Ishikawa T Hayashi K Iwatsuki Y Ishii K Nakayama K 《Pflügers Archiv : European journal of physiology》2003,447(2):142-149
Rhythmical contractions accompanied by an increase in cytosolic Ca2+ concentrations were produced in ring preparations of endothelium-denuded pulmonary arteries from monocrotaline-treated rats, but not in those from vehicle-treated rats, 2-3 h after a resting tension of 15 mN (150-180% of the initial wall length of the artery) was applied. The rhythmical contractions were abolished by nicardipine and ryanodine. Cyclopiazonic acid reduced the relaxation phase of the rhythmical contractions, finally leading to a sustained contraction. Similarly, apamin caused a sustained contraction, whereas charybdotoxin increased the amplitude of the rhythmical contractions. Glibenclamide had no apparent effects on them. Indomethacin and the prostaglandin H2/thromboxane A2 receptor antagonist SQ29548 abolished the rhythmical contractions and reduced the tension, but the thromboxane synthase inhibitor ozagrel had no effect. These results suggest that optimal stretch induces rhythmical contractions in the pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats, to which both Ca2+ influx through voltage-operated Ca2+ channels and Ca2+ release from the endoplasmic reticulum seem to contribute. It is also suggested that small-conductance Ca(2+)-activated K+ channels participate in the relaxation phase of rhythmical contractions. Furthermore, prostaglandin H2 released from nonendothelial cells is likely to play a pivotal role in the induction of rhythmical contractions. 相似文献
16.
Hibasami H Moteki H Ishikawa K Katsuzaki H Imai K Yoshioka K Ishii Y Komiya T 《International journal of molecular medicine》2003,11(1):23-26
Protodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated. PD displayed strong growth inhibitory effect against HL-60 cells, but weak growth inhibitory effect on KATO III cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with PD, but not in KATO III cells treated with PD. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 75.2, 96.3, and 100% after a 3-day treatment with 2.5, 5, and 10 microM PD, respectively. The fragmentation by PD of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent in the HL-60 cells. These findings suggest that growth inhibition by PD of HL-60 cells results from the induction of apoptosis by this compound in HL-60 cells. 相似文献
17.
Yasukazu Tanaka Kunio Oota 《Virchows Archiv : an international journal of pathology》1970,349(3):215-228
Summary The stereomicroscopic study of cystic disease of the breast revealed the presence of abnormal ductules near the terminal sites of the original lactiferous ducts. This alteration was the key feature of cystic disease since the involution of abnormal ductules possibly may have induced the stricture of the original duct by increasing fibrosis around the site of duct evolution. The phenomenon could contribute to the creation of cystic dilatation of distal ducts and acini. Multiple large cysts characterizing the morphology of cystic disease may represent the end stage of distended ducts and acini. Prolonged and repeated unbalanced stimulation of hormones could produce progressive and regressive alternations in the same breast. This modifies the original alteration into more pleomorphic and complicated types.
Clinical Investigator, Veterans Administration Hospital, San Francisco, California, U.S.A., Former Postgraduate Student, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
This investigation was carried out at the Department of Pathology, Faculty of Medicine, Tokyo Medical and Dental University from 1958 to 1960 and was partially supported by a special research grant of the Japanese Ministry of Education. 相似文献
Stereomikroskopische Studie der durch Mastopathie veränderten menschlichen MammaII. Die peripherische Form der Milchgangsevolution und ihre Beziehung zur Cystenmamma
Zusammenfassung Die stereomikroskopische Untersuchung sog. Cystenmmamen zeigt, daß die Cysten durch Ektasie der sog. Kanälchen-Endäste entstehen. Dagegen werden die Stamm-Milchgänge einer Involution zugeführt. An der Cystenbildung beteiligen sich auch die Acini. Als morphogenetische Reize kommen hormonelle Dysregulatonen in Frage. Durch die unterschiedliche Ausbildung der Kanälchen proliferation einerseits, die Involution sowie Cystenbildung andererseits resultiert ein buntes, wenig einheitliches Bild.
Clinical Investigator, Veterans Administration Hospital, San Francisco, California, U.S.A., Former Postgraduate Student, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
This investigation was carried out at the Department of Pathology, Faculty of Medicine, Tokyo Medical and Dental University from 1958 to 1960 and was partially supported by a special research grant of the Japanese Ministry of Education. 相似文献
18.
Social isolation stress augments angiogenesis induced by colon 26-L5 carcinoma cells in mice 总被引:3,自引:0,他引:3
Wu W Murata J Murakami K Yamaura T Hayashi K Saiki I 《Clinical & experimental metastasis》2000,18(1):1-10
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation. 相似文献
19.
20.
Kawakubo Y Kishimoto H Sato Y Yanagimoto K Tsuruta T Ogawa Y Kameya T 《Virchows Archiv : an international journal of pathology》1999,434(2):109-115
Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing
that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus
(HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected
in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In
situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was
performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV
by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV
infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection
and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in
normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated
with HCMV infection.
Received: 24 November 1998 / Accepted: 24 April 1998 相似文献