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101.
INTRODUCTION: Orotate phosphoribosyl transferase (OPRT), dihydropyrimidine dehydrogenase (DPD), and thymidylate synthase (TS) are initial key enzymes in the 5-fluorouracil (5-FU) metabolic pathway. The expression levels and activities of these three enzymes play important roles in the response of cancer patients to 5-FU-based chemotherapy. PURPOSE: The purpose of this study was to investigate the relationship between the activities of 5-FU metabolic enzymes and clinicopathologic factors in colorectal cancer. METHODS: We measured the activities of OPRT, DPD, and TS in colorectal cancer tissues. We also investigated the correlations between the activities of these three enzymes and clinicopathologic factors (histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, and vascular invasion). We examined 100 patients with surgically resected colorectal cancer. RESULTS: Poorly differentiated adenocarcinoma showed significantly higher DPD activities than did moderately differentiated or well-differentiated adenocarcinoma. In patients with lymph-node metastasis, OPRT activity was significantly lower than in patients without lymph-node metastasis. No significant relation was found between TS activity and histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, or vascular invasion. CONCLUSION: The response to 5-FU may be poor in patients with lymph-node metastasis, because of low OPRT activity, and in patients with poorly differentiated adenocarcinoma, because of high DPD activity.  相似文献   
102.
To clarify how Aβ deposits start in the brain, we examined the early to late stages of senile plaques and amyloid angiopathy in APPsw mice. All types of human senile plaques were observed in the mouse brains. The premature forms of cored plaques appeared first in the cerebral cortex of mice at 7–8 months old. Then, amyloid angiopathy emerged, followed by diffuse plaques consisting of Aβ1–42. Modifications of the N-terminus of Aβ were late phase phenomena. The premature forms of cored plaques were composed of central Aβ1–40 amyloid cores, surrounding amorphous Aβ1–42 deposits, and accumulation of Aβ1–42 in some peripheral cells. These cells were incorporated in amyloid cores, and these plaques developed to large cored plaques composed of Aβ1–40 and Aβ1–42. The size and number of cored plaques were increased with age. These findings indicate different evolution paths for cored plaques and diffuse plaques, and suggest the presence of a pathway that initiates with the intracellular accumulation of Aβ1–42 and leads to the development of classic plaques in human brain tissues.  相似文献   
103.
We examined the anti-tumor effect of a novel benzoic acid derivative, TAC-101 (4-[3,5-bis(trimethylsilyl) benzamide] benzoic acid) on models with liver metastasis. Oral administration of TAC-101 significantly inhibited spontaneous liver metastasis of AZ-521 (human gastric cancer ) by orthotopic implan-tation to athymic nude mice. It also inhibited both the liver metastasis of AZ-521 induced by intrasplenic injection and the secondary lung metastasis from the liver. In addition, TAC-101 inhibited the proliferation of Co-3 (human colon adenocarcinoma) that formed a single nodule in the liver of athymic nude mice by intrahepatic implantation. The growth inhibitory effect of TAC-101 on AZ-521 experimental liver metastasis was observed when treatment was started on day 7, 14, or 21 which may correspond to the progressive stage of liver metastasis in clinical settings. Multiple administration of TAC-101 (8 mg/kg/day) significantly prolonged survival time of the animals with liver met astasis by intrasplenic injection of AZ-521 (T/C = 230%) and A549 (human lung adenocarcinoma; T/C = 186%). These effects of TAC-101 were stronger than those of 5-FU, CDDP or ATRA. Furthermore, TAC-101 inhibited the binding of AP-1 to DNA on electrophoretic mobility shift assay using nuclear extract of AZ-521 cells, although ATRA did not inhibit. These findings suggested that TAC-101 may be a candidate for a new class of anti-cancer agents for liver metastasis. © Rapid Science Ltd.  相似文献   
104.
Oesophageal squamous cell carcinoma with lymphoid stroma   总被引:4,自引:0,他引:4  
Summary We treated a 70-year-old Japanese man with squamous cell carcinoma of the oesophagus with evidence of lymphoid stroma. The tumour consisted of a main lesion invading the muscular layer of the oesophagus, in association with wide areas of carcinoma in situ. The tumour stroma of the lesion was nondesmoplastic and was uniformly infiltrated mainly by abundant lymphocytes and plasma cells. Immunohistochemically, the lymphocytes consisted of a large number of T lymphocytes and a small number of B lymphocytes. S-100 protein positive cells were marked in the tumour cell nests and necrotic change of tumour cells was frequent. Abundant infiltration of lymphocytes and plasma cells was also wide-spread beneath the carcinoma in situ, together with the lymphoid follicles. Carcinoma with lymphoid stroma can occur not only in the breast, uterine cervix, nasopharynx and stomach but also in the oesophagus.  相似文献   
105.
106.
The function of the Fc receptors γ chain (FcRγ) for the expression of the T cell receptor (TCR) complex and for T cell development, especially for T cells localized in epithelia, was investigated by analyzing FcRγ-deficient mice. In wildtype mice, CD8αα+β?TCRαβ+ T cells of intestinal intraepithelial lymphocytes (i-IEL) utilized CD3ζ homodimers and ζ-FcRγ heterodimers, whereas CD8α α+β?TCRγδ+ i-IEL used ζ-FcRγ and FcRγ homodimers in the TCR complex. On the other hand, these T cells in FcRγ-deficient mice contained only ζ homodimers. The surface expression of the TCR complex was reduced in CD8αα+β?i-IEL and dendritic epidermal T cells (DETC) in these mice, whereas the development of these T cells was normal. The degree of reduction appeared to depend on the expression level of FcRγ. In contrast to these populations, TCRγδ+ intraepithelial T cells in reproductive organs (r-IEL) were dramatically decreased, suggesting that the development of r-IEL is FcRγ-dependent, probably due to the predominant usage of FcRγ homodimers in the TCR complex. These results indicate that the FcRγ chain contributes differently to the TCR expression and to the development of T cells localized in epithelia.  相似文献   
107.
This study examined the effects of voluntary abdominal breathing (VAB) on the electroencephalogram (EEG) in 22 healthy subjects. VAB was characterized by prolonged rhythmic contraction of abdominal muscles for 20 min in an eyes-closed condition. The breathing rate was instructed to be very slow, i.e., 3-4 breaths/min (inspiratory time for 6-8s and expiratory time for 9-12s). A low-frequency alpha band appeared immediately after eye closing, but it later disappeared and was replaced by a new development of a high-frequency alpha band 4-5 min after the onset of VAB. The subjects had a feeling of vigor-activity with a tendency of reduced anxiety during and/or after VAB, as assessed by POMS and STAI questionnaire scores. On the other hand, during resting in the eye-closed condition, the disappearance of the low-frequency alpha band was replaced by the occurrence of a theta/delta band. The subjects became drowsy in this condition. We therefore conclude that the increase in high-frequency alpha activity is linked to the state of vigor-activity with a tendency of reduced anxiety. Since the urinary serotonergic level significantly increased after the VAB, we suggest that the serotonergic neurons within the brain may produce the changes in the EEG patterns.  相似文献   
108.
109.
A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 × 35 × 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcino-embryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature.  相似文献   
110.
We compared the thin-section CT findings of 11 intrapulmonary lymph nodes with pathological findings and evaluated the possibility of CT scan differential diagnosis from pulmonary metastatic nodules. First, we retrospectively reviewed CT scan and pathological findings of intrapulmonary lymph nodes. The median size of these nodules was 6.2 mm. The nodules appeared round (n=3) or angular (n=8) in shape with a sharp border, and they were found below the level of the carina. The median distance from the nearest pleural surface was 4.6 mm, and 3 of the 11 nodules were attached to the pleura. On thin-section CT scan, linear densities extending from the intrapulmonary lymph nodes were frequently visualized, and were pathologically proven to be ectatic lymphoid channels. We then compared the thin-section CT findings of 8 metastatic nodules less than 1 cm in diameter with those of the 11 intrapulmonary lymph nodes. The median size of these nodules was 6.8 mm, and the median distance from the nearest pleural surface was 16 mm. All nodules appeared round in shape. None of the nodules had linear densities extending from the nodules. The linear densities on thin-section CT scan may be the most useful characteristic of intrapulmonary lymph nodes, when differential diagnosis from metastatic nodules is necessary.  相似文献   
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