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91.
Takahashi S Okada K Nagasawa H Shimada Y Sakamoto H Itoi E 《Virchows Archiv : an international journal of pathology》2004,444(5):454-458
We describe a case history of a 24-year-old male with osteogenesis imperfecta (OI) who developed osteosarcoma of the left thigh. High-dose ifosfamide therapy caused marked tumor regression of multiple lung metastases. Immunohistochemically, the tumor cells were diffusely positive for the p53 protein. Mutation of the p53 gene was not detected by direct genomic sequencing of exons 4–8. The radiographic characteristics, including irregularly distributed osteolytic lesions and cortical discontinuity, should not be confused with hyperplastic callus formation, a benign process. A biopsy is critical to establish the differential diagnosis between osteosarcoma and common hyperplastic callus formation in OI; however, it must be applied with great care. 相似文献
92.
Nakajima K Kinuya K Mizutani Y Hwang EH Michigishi T Tonami N Kobayashi K 《Annals of nuclear medicine》1999,13(1):5-11
Technetium-99m labeled diethylenetriaminepentaacetic acid (DTPA)-galactosyl human serum albumin (GSA) has been used for hepatocellular functional evaluation. This study proposed new and simple parameters to overcome the limitations of conventional parameters, and they were applied to the clinical staging of chronic liver dysfunction. The study group consisted of 93 patients including 81 with liver dysfunction and 12 control patients. In addition to the two conventional parameters, namely, receptor index (LHL15 = liver count divided by the sum of liver and heart counts at 15 minutes) and clearance index (HH15 = heart count at 15 minutes divided by the heart count at 3 minutes), 6 new parameters for Tc-99m GSA uptake and clearance were generated. The conventional receptor index of LHL15 showed a large variation depending on the size of region of interest (ROI) over the heart. The LHL15 normalized by the ROI size (nLHL15) showed more stable data and a better separation of mild liver dysfunction. A hyperbolic relationship between the LHL15 and HH 15 changed to a linear relationship by using the nLHL15 index. The combination of the liver to heart average count ratio at 15 minutes (LH 15) and T-half (minute) of the heart count also could differentiate each stage well. In conclusion, the use of the ROI-area normalized nLHL is recommended instead of the conventional LHL15. The indices of LH15 and T-half could be alternatively used as practical parameters for clinical staging in liver function. 相似文献
93.
Ascorbate-enhanced nitric oxide (NO) production in lipopolysaccharide (LPS)- and interferon-gamma (IFN-gamma)-activated macrophage J774.1 cells through the inducible nitric oxide synthase (iNOS) pathway. The iNOS gene was synergistically induced by LPS and IFN-gamma. The inductive mechanism of ascorbate on the iNOS gene was studied by examining the degradation of I kappa B alpha by Western blotting, activation of the nuclear factor kappa B (NF-kappa B) by gel shift assays, and protein levels of interferon regulatory factor 1 (IRF-1) in LPS- and IFN-gamma-activated cells. Ascorbate had no effect on the onset of either I kappa B alpha degradation or the nuclear translocation of NF-kappa B, but it delayed the recovery of I kappa B alpha. The prolonged degradation of I kappa B alpha caused by ascorbate in LPS- and IFN-gamma-activated cells paralleled elevated NF-kappa B binding to DNA, which led to an increase in the iNOS protein level. Ascorbate alone did not induce I kappa B alpha degradation or NF-kappa B activation. Furthermore, ascorbate exerted no effect on the expression of I kappa B alpha and ubiquitin genes in the activated cells. Ascorbate could modulate NF-kappa B DNA binding activity in response to combined LPS and IFN-gamma activation, which increases NO production in activated macrophages. 相似文献
94.
T Mizutani M Murakami M Shirai M Tanaka K Nakanishi 《Journal of applied toxicology : JAT》1999,19(3):193-198
Methimazole (MMI) (>0.1 mmol kg(-1), p.o.) given in combination with DL-buthionine sulphoximine (BSO) (3 mmol kg(-1), i.p., 1 h before MMI administration), an inhibitor of glutathione (GSH) synthesis, caused liver injury in mice. The injury was characterized by centrilobular necrosis of hepatocytes and an increase in serum alanine transaminase (ALT) activity. Methionazole (2 mmol kg(-1)) alone resulted in only a marginal increase in serum ALT activity, but produced no histopathological changes in the liver. Pretreatment with hepatic cytochrome P-450 monooxygenase inhibitors--cobalt chloride, isosafrole, methoxsalen, metyrapone and piperonyl butoxide-prevented or tended to suppress the hepatotoxicity induced by MMI in combination with BSO. Treatment with N,N-dimethylaniline and ethyl methyl sulphide, competitive substrates of flavin-containing monooxygenases (FMO), also resulted in remarkable suppression of the hepatotoxicity caused by MMI in combination with BSO. These results suggest that MMI is activated by reactions mediated by both cytochrome P-450 monooxygenases and FMO, and that the inadequate rates of detoxification of the resulting metabolite are responsible for the hepatotoxicity in GSH-depleted mice. 相似文献
95.
K. Mitsuishi A. Takahashi M. Mizutani K. Ochiai C. Itakura 《Acta neuropathologica》1993,86(6):578-581
Morphological effects of a neurotoxin, ,-iminodipropionitrile (IDPN) were analyzed in normal and cogenitally neurofilament (NF)-deficient Japanese quails. These quails (6 weeks old) were injected intraperitoneally with IDPN (0.2 g/kg body weight) three times every 3 days. They were necropsied at 10 to 12 days after the first injection. In normal quails, axonal swellings were observed histologically in the ventral motoneurons, ventral root, commissura grisea and spinal ganglion in the cervical and synsacral spinal cord. Electron microscopically, the changes consisted of increased NFs, with scattered mitochondria, smooth endoplasmic reticulum and microtubules. The myelin sheaths of the involved nerves were thinner than those of the normal axons. These lesions were similar to those induced by IDPN intoxication in mammalian experimental animals. In NF-deficient quails injected with IDPN, no axonal changes were detected. These findings suggested that IDPN selectively attacked the NFs. 相似文献
96.
Damon R Demady Ezra R Lowe Andrew C Everett Scott S Billecke Yasuhiko Kamada Anwar Y Dunbar Yoichi Osawa 《Drug metabolism and disposition》2003,31(7):932-937
It has been shown that administration of cigarette smoke to rats leads to loss of neuronal nitric-oxide synthase (nNOS) activity and nNOS protein in penile tissue. The exact mechanism for this loss of activity and protein is not known. In the current study, we investigated whether extracts prepared from cigarette smoke or from the cigarette itself could directly inhibit nNOS activity. We discovered that the cigarette smoke extract and the cigarette extract cause a time-, concentration-, and calmodulin-dependent inactivation of nNOS in an in vitro system containing the purified enzyme. L-Arginine, but not D-arginine, protects nNOS from this time-dependent inactivation, suggesting an active site directed event. The kinetics of inactivation are consistent with the metabolism-based or suicide inactivation of nNOS. Based on studies with other metabolism-based inactivators, this cigarette-mediated inactivation may render nNOS more susceptible to proteasomal degradation and thereby may explain the loss of nNOS protein in vivo. The component(s) responsible for nNOS inactivation is not volatile, is not retained by a 3,000 molecular weight cut-off membrane, binds to activated charcoal, and is highly water-soluble under both acidic and basic conditions. The discovery of a direct inactivation of nNOS by an organic, cationic compound(s) present in tobacco and tobacco smoke provides a basis for further study of not only the mechanisms responsible for the biological effects of tobacco but also a search for a potentially novel inactivator of nNOS. 相似文献
97.
Kanazawa R Mizutani N Sanno N Shimura T Teramoto A 《No shinkei geka. Neurological surgery》2000,28(11):1029-1033
A 46-year-old male was admitted to our hospital with headache, high fever and subsequent consciousness disturbance. Spinal fluid examination intimated aseptic meningitis. Not only these symptoms but bladder dysfunction was presented. The patient was treated with conservative therapy and bladder dysfunction was resolved a month and a half later. We report a case of urinary retention secondary to aseptic meningitis and review the clinical presentation and treatment. 相似文献
98.
Yumi Kojima Yoichi Aoki Hiroaki Kase Shoji Kodama Kenichi Tanaka 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(3):143-146
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging)
in the evaluation of preinvasive and early invasive cancer of the cervix.
Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion
underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated
for tumor detection and compared with results of histologic examination of the surgical specimens.
Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging,
whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and
5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images.
In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR
images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic
MR imaging.
Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced
MR imaging. 相似文献
99.
H. Nagano K. Mizutani K. Sawa Y. Ozaki A. Murakami 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(5):330-333
We report a case of stage IV ovarian clear cell adenocarcinoma (OCCA) in a 72-year-old woman who was treated postoperatively
with etoposide combined with cisplatin (EP). The patient exhibited bulky intrapelvic and para-aortic lymph nodes with metastases
to the cervical lymph nodes. The primary lesion was resected and, postoperatively, she received one course of combination
chemotherapy consisting of cyclophosphamide, 500 mg/m2; doxorubicin, 50 mg/m2; and cisplatin, 70mg/m2 (CAP), followed by six courses of combination chemotherapy consisting of etoposide, 80mg/m2 days 1 through 5 and cisplatin, 70 mg/m2 on day 5 every 4 weeks. After five courses of EP, the lymph node metastases had virtually disappeared. The patient is now
disease-free 21 months after the initial surgery. These findings suggest that EP may be useful in treating OCCA. 相似文献
100.
Primary transitional cell carcinoma of prostate: a case report 总被引:2,自引:0,他引:2
Uemura M Imamura R Inoue H Nishimura K Mizutani S Miyoshi S Mise T 《Hinyokika kiyo. Acta urologica Japonica》2000,46(7):495-498
A 67-year-old male was admitted with a three-month history of voiding difficulty. Prostate specific antigen remained within the normal limit. Under the diagnosis of benign prostatic hypertrophy, transurethral resection of prostate was performed. Pathological examination of the resected specimens of the prostate revealed transitional cell carcinoma. Two courses of systemic M-VAC (methotrexate, vinblastine, doxorubicin, cisplatin) chemotherapy were performed, followed by cystoprostatourethrectomy, pelvic lymphadenectomy, and ileal conduit construction. Now one year has elapsed, with no clinical signs of recurrence. 相似文献