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31.
The localization of pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamus-pituitary system in rats was examined in light and electron microscopic immunocytochemistry using a specific antiserum to synthetic PACAP 1–38 (R0831). In light microscopic study, intensely PACAP-immunostained perikarya were observed in the supraoptic and paraventricular magnocellular nucleus in the hypothalamus. In the median eminence, many immunoreactive nerve fibers were observed in the internal layer, but a few immunoreactive terminals were noticed in the external layer. In the pituitary gland, numerous immunoreactive nerve fibers were observed in the posterior lobe. In the intermediate lobe, moderately immunostained cells were observed, but in the anterior lobe no immunostained cells were noticed. In electron microscopic study, PACAP-immunoreactivity was examined by avidin-biotin peroxidase complex method. In the perikarya of the supraoptic and paraventricular magnocellular nucleus, DAB-reaction products were distributed diffusely in the cytoplasmic matrix, frequently attaching to the rough-surfaced endoplasmic reticulum. In the nerve terminals of the posterior lobe, reaction products were observed among the secretory granules, but sometimes upon them. In the cells of the intermediate lobe, reaction products were also distributed in the cytoplasmic matrix.  相似文献   
32.
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131I-labeled intact CEA102 or its F(ab')2. Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy.  相似文献   
33.
KM2210, a conjugate of estradiol and chlorambucil (CBL), which was originally developed as an anti-breast cancer agent, inhibits proliferative response of human mononuclear cells to alloantigens in mixed lymphocyte culture in a dose-dependent manner, but has no effect on their response to phytohemagglutinin. Neither estradiol benzoate nor CBL alone showed these unique actions. The suppressive effect of KM2210 on MLC was abrogated by adding of anti-transforming growth factor-beta (TGF-beta) antibody to the culture, but was not affected by the addition of interleukin-2, suggesting that KM2210, unlike CBL, displays its actions via TGF-beta. In experimental allogeneic bone marrow transplantation using mice, daily oral administration of KM2210 (2 mg/kg/day) for 30 days posttransplant significantly inhibited the alloantigen-specific immune reactions. Furthermore, the survival rate of the KM2210-treated mice was significantly higher than that of the cyclosporine-treated (2 mg/kg/day, p.o.) mice, and no adverse effect of KM2210 on hematopoietic recovery was found. These results strongly suggest possible clinical benefits of KM2210 as a new immunosuppressive agent for the prevention and treatment of graft-versus-host disease and other allospecific immune reactions.  相似文献   
34.
Adult T-cell leukemia-derived factor (ADF), originally defined as an interleukin-2 receptor inducer, is a human thioredoxin homologue. ADF is detected in many malignant tissues and has a growth-promoting effect on transformed cells. In this study, ADF expression was examined immunohistochemically in human liver cell lines and liver tissues, and its growth-promoting effect was tested on human hepatoma cells. On three liver cell line--PLC/PRF/5, HepG2, and Chang liver cells--ADF stained positively and also was detected by immunoblotting. ADF had strong staining in the fetal liver (n = 8), although it was faint in the normal adult liver (n = 6). In hepatocellular carcinoma (n = 25), ADF expression generally was enhanced and was very strong in 52% (13 of 25) of the cases, although it was moderate in cases of chronic hepatitis or cirrhosis. ADF augmented the growth of PLC/PRF/5 cells and showed an additive effect with epidermal growth factor. These results indicate possible involvement of ADF in cell activation and growth of hepatocytes, as is the case with lymphocytes.  相似文献   
35.
Kimura's disease is a rare disorder that involves regional lymph nodes and the major salivary glands, which become infiltrated by eosinophils and lymphocytes. Renal lesions associated with Kimura's disease are rare. We describe the case of a 60-year-old Japanese woman who first noted a nodular mass in a salivary gland. As the nodule grew, nephrotic syndrome and heart failure developed. A biopsy of the nodule revealed Kimura's disease, and surgical excision was performed. After the operation, the heart failure and nephrotic syndrome, which were diagnosed as minimal change disease on renal biopsy, improved rapidly without steroid therapy. Four months later, the nephrotic syndrome recurred without recurrence of Kimura's disease. The patient showed marked improvement during prednisolone therapy (40 mg/d) and was in complete remission 4 weeks after the initiation of steroid therapy. This case shows that surgical excision and prednisolone therapy are useful for nephrotic syndrome associated with Kimura's disease.  相似文献   
36.
As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A fteta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with 5. pyogenes , or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.  相似文献   
37.
38.
The influence of phagocytosis on hepatic energy metabolism was investigated in rats injected with colloidal carbon. Following injection of 6 mg colloidal carbon per 100 g body wt (BW) the hepatic energy charge potential (ECP) remained unchanged. However, oxidative phosphorylation of the isolated mitochondria (PR) increased significantly to 120 and 124% of the control at 1 and 3 hr, respectively, and returned to the normal range at 6 hr. The pyruvate level rose to 195 and 150% at 3 and 6 hr. The lactate level was elevated to 195 and 143% at 3 and 6 hr. Following injection of 20 mg colloidal carbon per 100 g BW, the ECP decreased from 0.865 to 0.783 at 1 hr, but recovered to the normal range thereafter. The PR increased more markedly to 135% at 1 hr, concomitant with an elevation of the ketone body ratio. At 3 hr it remained elevated at 118%, but returned to the normal level at 6 hr. The pyruvate and lactate levels increased to more than 250% at 1 and 3 hr. At 6 hr, the lactate level returned to the control level, but the pyruvate level showed still higher level than the control. These results indicate that phagocytosis exerts an acute metabolic load on the total liver. It was tentatively proposed that parenchymal and nonparenchymal cells in the liver have interrelation in the energy metabolism, and that an enhancement of hepatocellular mitochondrial phosphorylative activity occurs to assist the accelerated metabolism due to phagocytosis.  相似文献   
39.
A 44-year-old housewife was found to have coarctation of the abdominal aorta secondary to Takayasu's arteritis. Since she also had mitral stenosis, possible etiological relation between Takayasu's arteritis and mitral stenosis is suspected.  相似文献   
40.
Tc-99m tetrofosmin is a lipophilic, cationic perfusion imaging agent that changes to Tl-201 in detecting coronary artery disease during exercise testing. The purpose of this study is to evaluate the usefulness of Tc-99m tetrofosmin dipyridamole stress imaging combined with low level exercise for the detection of coronary artery disease. We examined 42 patients and 10 normal volunteers who also underwent coronary angiography. A one-day protocol was used: in the stress study, 296 MBq of tetrofosmin was injected and in the rest study 888 MBq was injected. After intravenous administration of dipyridamole (0.142 mg/kg/min for 4 minutes), the patient was exercised on a bicycle ergometer for 3 min (25 Watts). Tetrofosmin was injected 2 minutes after dipyridamole infusion during the exercise. Single photon emission computed tomographic images were obtained 30 minutes after the tracer injection. Images were interpreted as abnormal in 36 of 42 patients with coronary artery disease, and normal in all of 10 normal volunteers. The overall sensitivity of detection of coronary artery disease was 83.3% and the normalcy rate was 100%. The diagnostic values for the detection of significant stenosis in the three major arteries were: LAD sensitivity 83%, specificity 92%; LCX sensitivity 47%, specificity 91%; RCA sensitivity 75%, specificity 83%. Of the 66 arteries with more than 50% stenosis, 48 arteries were correctly identified. Of the 36 with more than 70% stenosis, 31 were identified. Scintigraphic evidence of multivessel disease was found in only 9 patients (50%). A protocol of Tc-99m tetrofosmin SPECT combined with low level exercise after dipyridamole is therefore useful for the detection of the coronary artery disease.  相似文献   
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