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51.
Inagaki M Yabuki H Hashimoto M Maguchi M Kino S Sawa M Ojima H Tokusashi Y Miyokawa N Kusano M Kasai S 《Surgery today》1999,29(12):1260-1263
We describe herein the case of a 51-year-old woman in whom metastatic tumor seeding of the percutaneous transhepatic biliary
drainage tract occurred following a pancreatoduodenectomy for carcinoma of the distal common bile, duct. An abdominal computed
tomography scan done 6 months after the initial operation detected a hepatic lesion located at the site of the previous percutaneous
transhepatic biliary drainage tract. Implantation of bile duct carcinoma in the drainage tract was diagnosed, and the recurrent
tumor was successfully resected by performing a subsegmentectomy of segment 3 and removal of the adjacent abdominal wall.
At present, 5 years and 4 months after the second resection, the patient is in good health without any signs of recurrence.
This case report demonstrates that an aggressive surgical approach should be performed for tumor seeding of a transhepatic
biliary catheter tract. 相似文献
52.
Nakano N Hatakeyama Y Fukatsu R Hayashi S Fujii M Fujimori K Takahata N 《Progress in neuro-psychopharmacology & biological psychiatry》1999,23(6):1053-1062
1. Three patients with Alzheimer's disease (AD) and three healthy controls (HC) were examined for eye-head coordination. Regional cerebral blood flow (rCBF) was measured in AD patients. 2. Eye-head coordination was analyzed using a Vision analyzer, and magnetic sensors. The authors measured the rCBF with 123I-IMP, and 99mTc-ECD SPECT. 3. AD reduced gaze accuracy and head movements, and prolonged the latency of saccade as compared to HC. AD patients had a tendency to focus on the target by using eye movements only. 4. AD reduced the rCBF in the inferior parietal part and the visual area, relative to the motor area. Damage of these areas may have caused the eye-head coordination disorders in the AD patients. 相似文献
53.
Nobushige Yamashita Shiro Hoshida Kinya Otsu Naoyuki Taniguchi Tsunehiko Kuzuya Masatsugu Hori 《British journal of pharmacology》1999,128(2):412-418
1 We utilized a rat model of myocardial infarction to investigate whether cardioprotection by monophosphoryl lipid A (MLA) is provided in the early and late phases, as well as to determine whether this cardioprotection may be related to the activation of manganese superoxide dismutase (Mn-SOD), an intrinsic radical scavenger. 2 Pretreatment with MLA (0.5 or 1.0 mg kg-1, i.v.) 24 h prior to 20-min left coronary artery (LCA) occlusion and 48-h reperfusion significantly decreased the incidence of ventricular fibrillation (VF) during ischaemia, as well as infarct size. Pretreatment with lower concentrations of MLA, however, was ineffective. 3 When we examined the time course of MLA (0.5 mg kg-1)-induced cardioprotection, both infarct size and the incidence of VF were significantly reduced in rats pretreated with MLA 0.5 h and 24 h before occlusion. We observed no differences, however, 2 and 72 h after MLA treatment. 4 The activity of Mn-SOD paralleled the cardioprotective effects of MLA. Mn-SOD activity in the myocardium was significantly enhanced in rats pretreated with MLA (0.5 mg kg-1) 0.5 and 24 h before. Mn-SOD activity was not altered, however, in rats pretreated 2 or 72 h before. Lower MLA concentrations were not effective even 24 h after the treatment. 5 We conclude that MLA treatment induced a biphasic pattern of cardioprotection. The pattern of Mn-SOD activity suggests that this enzyme may play a major role in the acquisition of cardioprotection against ischaemia-reperfusion injury. 相似文献
54.
Kozutsumi D Kawashima A Sugimoto T Kotohda Y Fujimori S Takami M Kohno T Oikawa T Sugino E Choshi T Hibino S 《Biopharmaceutics & drug disposition》1999,20(6):277-284
Medroxyprogesterone acetate (MPA) is widely used in endocrine therapy for breast cancer and other diseases. Recently, it has been demonstrated that 9alpha-fluoromedroxyprogesterone acetate (FMPA) also has anti-tumour activity in chemical-induced rat mammary tumour and its activity is greater than that of MPA. In the present study, the physico-chemical properties of FMPA and MPA and their pharmacokinetics in female rats were investigated. Partition coefficients (log P) of FMPA and MPA were 3.1 and 3.8, respectively, while the solubilities of FMPA and MPA in phosphate buffer saline were 3.8 and 1.1 microg/mL, respectively. When the two agents were intravenously or orally administered into female rats, there was no significant difference between their plasma concentrations. However, unmetabolized drug excreted into urine accounted for 4.7 and 0.7% of the intravenous dose of FMPA and MPA, respectively. The free fraction of FMPA in rat plasma was approximately four times that of MPA. Assuming the well-stirred model, hepatic intrinsic clearances of FMPA and MPA were estimated to be 64 and 293 L/h per kg, respectively. In addition, the free fraction of FMPA in blood is estimated to be higher than that of MPA, which may explain the higher anti-tumour activity. 相似文献
55.
An analysis of monoclonal antibody distribution in microscopic tumor nodules: consequences of a "binding site barrier" 总被引:8,自引:0,他引:8
Rational in vivo application of monoclonal antibodies for diagnosis and therapy of cancer requires an understanding of both the global and microscopic pharmacology of macromolecular ligands. Here, we introduce a new mathematical model for antibody distribution into small, prevascular, densely packed nodules (representing either primary or metastatic tumor). For the analysis, we link together several aspects of antibody pharmacology: the global (whole body) pharmacokinetics; transcapillary transport into normal tissue interstitium surrounding the nodule; diffusion into the nodule; nonspecific binding and/or partitioning; specific binding to tumor antigen; metabolism; and lymphatic outflow from the tissue space. Input parameter values are estimated from experimental studies in vitro, in animals, and in clinical trials. Our aim is to explore the sensitivity of antibody localization to variation in three of the important parameters of this model: the rate of transcapillary transport; the rate of lymphatic outflow; and the antigen density. Predictions based on this analysis include the following: (a) High rates of transcapillary transport influx or low rates of lymphatic efflux will enhance antibody percolation into the tumor nodule at early times after injection and increase the average antibody concentration in the tumor at all times; (b) Changes in antibody influx rate will affect the antibody distribution in the tumor at earlier times than do changes in the efflux rate; (c) Reducing the antigen concentration will increase the uniformity of antibody penetration but lower the average concentration in the tumor at all times after injection; and (d) Counter to intuition, lowering the antigen concentration can increase the peak concentrations achieved toward the center of the nodule. If, in addition, there is any metabolism of bound antibody, the concentration-time integral (i.e., the "area under the curve") for the center of the nodule will also be increased by decreasing the antigen concentration. These predictions directly reflect the "binding site barrier" hypothesis of Weinstein et al. (Ann. NY Acad. Sci., 507: 199-210, 1987) and Fujimori et al. (Cancer Res., 49:5656-5663, 1989; J. Nucl. Med., 31:1191-1198, 1990). In general, and perhaps surprisingly until one considers the problem carefully, the parameters governing antibody percolation can have opposite effects on the uniformity of antibody distribution at early and late times. These calculations, using the PERC program set, were done for antibodies, but we believe that the "binding site barrier" will also prove important for other injected macromolecules, for at least some highly bindable injected small molecules, for lymphokines and cytokines released from transfected cells injected in vivo, and, indeed, for endogenous species such as the autocrine-paracrine factors. 相似文献
56.
Takeyuki Yatsu Masanao Sanagi Akira Fujimori Yuichi Tomura Kazumi Hayashi Masayuki Tanahashi Osamu Inagaki 《Pharmacological research》2003,47(3):243-252
Several factors such as proteinuria and renal fibrosis may be important in the progression of many forms of chronic renal diseases. The purposes of the current study were to investigate the progressive renal failure of the rats with surgical renal mass reduction (RMR) and the effect of the angiotensin-converting enzyme (ACE) inhibitor, lisinopril, and to document correlation of several factors associated with progressive renal failure. Rats were subtotal (5/6) nephrectomized by resection of the renal poles and sham-operated. The functional, histological and haematological changes of the rats were studied for up to 10 weeks. After 2 weeks of RMR, oral administration of lisinopril (10 mg kg(-1) per day) was performed for 8 weeks. RMR resulted in progressive renal failure with proteinuria, monocyte/macrophage (ED1+) infiltration, anaemia as assessed by haemoglobin and haematocrit (Htc), renal hypertrophy as assessed by left kidney to body weight ratio (BKW/BW), and renal fibrosis as assessed by glomerular lesions and tubulointerstitial changes. Lisinopril exhibited renoprotection with antiproteinuric effect and inhibition of monocyte/macrophage (ED1+) infiltration. However, beneficial effect of lisinopril on anaemia was not observed. At 10 weeks after surgery, severity of proteinuria positively correlated with plasma creatinine (Pcr), BKW/BW, histological damage, and systolic blood pressure, and negatively correlated with haemoglobin. Severity of tubulointerstitial changes positively correlated with Pcr and blood urea nitrogen, and negatively correlated with haemoglobin and Htc. Moreover, monocyte/macrophage (ED1+) infiltration positively correlated with severity of proteinuria and tubulointerstitial changes. These findings strongly support that proteinuria, monocyte/macrophage infiltration and renal fibrosis appear to play principal roles in the progressive renal failure with anaemia and renoprotection of ACE inhibition may be mediated by multiple actions of ACE inhibitor. The present study confirms that rats with RMR is useful to explore target molecules for renoprotective drugs and evaluate renoprotective effect of new molecular entities. 相似文献
57.
Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy. 总被引:3,自引:0,他引:3
Ichiro Ogino Naoyuki Okamoto Yoshimi Ono Tatsuo Kitamura Hiroki Nakayama 《Radiotherapy and oncology》2003,68(1):61-67
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight. 相似文献
58.
Evaluation of cell proliferation and apoptosis in Helicobacter pylori gastritis using an image analysis processor. 总被引:4,自引:0,他引:4
Yasuo Ohkura Tadashi Furihata Hitoshi Kawamata Masafumi Tabuchi Keiichi Kubota Akira Terano Taro Sakai Takahiro Fujimori 《Gastric cancer》2003,6(1):49-54
BACKGROUND: Infection of the gastric mucosa by helicobacter pylori is primarily responsible for gastritis, gastric ulcer, adenocarcinoma, and lymphoproliferative disorders. H. pylori appears to accelerate apoptosis and the proliferation of the gastric epithelium directly or indirectly. To precisely assess the proliferative and apoptotic profile of .H pylori-infected gastric mucosa, a quantitative imaging system is now required. METHODS: Fifty-two patients with H. pylori gastritis were the subjects of the study. Biopsy materials were taken from at least two sites (usually three to five sites) including the antrum and corpus. The grade of gastritis was evaluated by the updated Sydney System. The proliferative and apoptotic profile was examined by Ki-67 immunohistochemistry and by a terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling method. In addition, Ki-67-positive cells were quantitated by an image processor for analytical pathology (IPAP) system. RESULTS: H. pylori density and polymorphonuclear neutrophil activity were significantly decreased after H. pylori eradication ( P< 0.0001). Chronic inflammation (P< 0.0001) and lymphoid follicle numbers ( P < 0.0005) were also significantly decreased after the eradication. Glandular atrophy and intestinal metaplasia were slightly decreased after eradication, but the decrease did not reach the significant level. the Ki-67 labeling index was significantly decreased after the eradication P< 0.0001). The apoptosis index was also decreased after the eradication, but this decrease did not reach the significant level ( P = 0.06). CONCLUSION: our data suggest that the activation of proliferative cells and induction of apoptosis in the gastric mucosa is a response to H. pylori-induced mucosal damage. Moreover, IPAP may be a useful technology for evaluating the results of immunohistochemistry, and it could provide quantitative and reliable data for studying H. pylori gastritis. 相似文献
59.
Fujimori KE Takeuchi K Yazaki T Uyemura K Nojyo Y Tamamki N 《The Journal of comparative neurology》2000,417(3):275-288
In the telencephalon, the corticospinal (CS), callosal, and hippocampal commissural neurons are the major types of neurons that have axons crossing the midline of the brain. To understand the mechanisms involved in crossing the midline structure and to examine whether the expression patterns of L1 and TAG-1 in the commissural neurons are similar to those in the spinal cord, we investigated L1 and TAG-1 expression in these neurons in rats by using a double-labeling technique involving retrograde labeling and in situ hybridization. Expression of L1 messenger RNA was detected in the retrogradely labeled CS projection neurons by 1,1;-dioctadecyl-3,3, 3;,3;-tetramethylindocarbocyanine perchlorate (DiI) injection into the pons at embryonic day (E) 19, but expression of TAG-1 messenger RNA was not detected in these neurons. Also, after their axons crossed the pyramidal decussation, continued expression of L1 but no expression of TAG-1 in the CS projection neurons was shown by an additional double-labeling experiment involving DiI injection into the spinal cord at postnatal day (P) 1. An immunohistochemical study showed that L1 was continuously present in each level of the CS tract at E21 and P3, but TAG-1 immunoreactivity was not found in any level at any stage. Finally, we examined the expression of L1 and TAG-1 messenger RNAs in the callosal and hippocampal commissure neurons after their axons had crossed the midline by using the double-labeling technique. In both cases, hybridization signals of the L1 and TAG-1 messenger RNAs were observed in the retrogradely labeled neurons at P3. These results suggest that the roles of L1 and TAG-1 in the formation of the commissures in the forebrain are different from their roles in the spinal cord. 相似文献
60.
Shin-Ichiro Sugiyama Naoyuki Shimada Hiroyuki Miyoshi Kiyoshi Yamauchi 《Toxicological sciences》2005,88(2):367-374
We developed a thyroid hormone (TH) inducible primary screening assay for the identification and assessment of man-made chemicals that interfere with the TH-signalling pathway within target cells. The assay was developed in a Xenopus laevis cell line that was transduced with a self-inactivating (SIN) lentivirus vector (LV) containing a luciferase gene. The luciferase activation in this cell line was TH-specific: 3,3',5-L-triiodothyronine (T(3)) > 3,3'5-L-triiodothyroacetic acid (Triac) > 3,3',5-D-triiodothyronine (D-T(3)), > L-thyroxine (T(4)) > 3,3',5'-L-triiodothyronine (rT(3)). The application of the ligand-dependent luciferase assay for screening for thyroid system-disrupting chemicals revealed that three phthalates (dicyclohexyl phthalate, n-butylbenzyl phthalate, and di-n-butyl phthalate), two herbicides (ioxynil and pentachlorophenol) and a miticide (dicofol) had 3,3',5-L-triiodothyronine- T(3)- antagonist activity at concentrations ranging from 10(-6) to 10(-5) M. These chemicals also inhibited the expression of the endogenous primary T(3)-response TH nuclear receptor beta (TRbeta) gene. The inhibitory characteristics of these chemicals were similar for both assays performed, although the assay for T(3)-dependent activation of TRbeta gene was more sensitive than the luciferase assay. These results indicate that the luciferase assay was a rapid method with a small intra-assay variation for the primary screening of thyroid system-disrupting chemicals. Of the six chemicals, only n-butylbenzyl phthalate and pentachlorophenol exhibited T(3)-antagonist activity in an in vivo metamorphosis-based assay. It should be noted that chemicals elicited thyroid system-disrupting activity in the luciferase assay did not always interfere with the thyroid system in vivo. 相似文献