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51.
52.
TJ Yoon YC Yoo TB Kang YJ Baek CS Huh SK Song KH Lee I Azuma JB Kim 《Canadian Metallurgical Quarterly》1998,20(4-5):163-172
We here demonstrated the prophylactic effect of an extract (KM-110) from Viscum album coloratum, a Korean mistletoe, on tumor metastasis produced by highly metastatic tumor cells, colon 26-M3.1 carcinoma, B16-BL6 melanoma and L5178Y-ML25 lymphoma cells, using experimental models in mice. Intravenous (i.v.) administration of KM-110 (100 microg/mouse) 2 days before tumor inoculation significantly inhibited lung metastasis of B16-BL6 and colon 26-M3.1 cells, and liver and spleen metastasis of L5178Y-ML25 cells. The prophylactic effect of KM-110 on tumor metastasis was evident with various administration routes, i.e. subcutaneous, oral, intranasal as well as i.v., and was dependent upon the dose of KM-110 administered. Furthermore, mice given KM-110 (100 microg) 2 days before tumor inoculation showed significantly prolonged survival rates compared with the untreated mice. In a time course analysis of NK activity, i.v. administration of KM-110 (100 microg) significantly augmented NK cytotoxicity to Yac-a tumor cells from 1 to 3 days after KM-110 treatment. Furthermore, depletion NK cells by injection of rabbit anti-asialo GM1 serum completely abolished the inhibitory effect of KM-110 on lung metastasis of colon 26-M3.1 cells. These results suggest that KM-110 possesses immunopotentiating activity which enhances the host defense system against tumors, and that its prophylactic effect on tumor metastasis is mediated by NK cell activation. 相似文献
53.
The effects of glyceryl nonivamide (GLNVA) on ionic currents were compared and examined in rat pituitary GH3 cells. Hyperpolarization-activated K+ currents in GH3 cells bathed in high-K+ Ca2+-free external solution were studied to assess effects of GLNVA on the an inwardly rectifying K+ current (I(K(IR))). GLNVA is very potent in blocking I(K(IR)) in a concentration-dependent manner, with a half maximal concentrations of 0.1 microM. The complete block of I(K(IR)) achieved with concentrations > or = 1 microM revealed the presence of a non-inactivating current. We also found that GLNVA at a concentration above 30 microM inhibited L-type voltage-dependent Ca2+ current and two components of K+ outward currents, while GLNVA (< or = 3 microM) did not have any effect on them. This study shows that GLNVA, in addition to retaining the capability of eliciting peptidergic neurons, is a selective block of I(K(IR)) in GH3 cells and will provide a useful tool for characterizing I(K(IR)) and understanding its physiological function. In addition, the carefulness should be taken about the interpretation of GLNVA-mediated responses in vivo or in vitro. 相似文献
54.
SJ Janssen D Bunick C Finnigan-Bunick YC Chen R Hess JM Bahr 《Canadian Metallurgical Quarterly》1998,30(5):554-561
Regulation of the excurrent ducts of the testis is not well understood, particularly in avian species. To investigate the role of steroid hormones in the male reproductive tract, we developed a primary cell culture of epithelia isolated from rooster ductuli efferentes (efferent ductules). Efferent ductules of the avian testis comprise 77% of the epididymal region and form a mass of tubules containing a heavily folded epithelium enmeshed in connective tissue. The epididymal region was separated by microdissection and small epithelial plaques isolated by serial digestion with collagenase, elastase and repeated pipetting. Isolated cell plaques were cultured in a bicameral chamber on Millicell-CM inserts coated with two layers of basement membrane matrix, consisting primarily of laminin and Types I and IV collagen. Active ciliary beat was observed before plating and this activity was maintained for 14 days in culture. Cell plaques attached within 24 h and outgrowths formed a confluent monolayer by 5-6 days. The epithelial nature of cultured cells was demonstrated by immunocytochemical staining for cytokeratin. Light and electron microscopy confirmed that morphology and polarity of the original epithelial cells were maintained in culture. Cultured efferent ductal epithelium was cuboidal in shape and maintained many of the cytoplasmic organelles typical of these cells in vivo. The uptake of cationic ferritin indicated the endocytotic activity of these cultured cells was maintained. Estrogen receptor mRNA expression was maintained in cultured cells. These data demonstrate avian efferent ductal epithelium can be isolated and grown in defined culture medium for the purpose of determining the role of hormones and other factors in regulating the function of the epididymal region in the bird. 相似文献
55.
OBJECTIVE: We tested the hypothesis that nitric oxide synthesis by the kidney is increased in children with primary nephrotic syndrome. METHODS: We examined the urinary excretion of nitrite, a stable metabolite of nitric oxide, using the Griess reaction, in children with nephrotic syndrome. RESULTS: In comparison with healthy children, patients with minimal change nephrotic syndrome had increased urinary nitrite excretion regardless of whether the disease was in relapse or remission (p < 0.025). In contrast, urinary nitrite excretion was similar in control subjects and patients with focal segmental glomerulosclerosis or IgA nephropathy. CONCLUSION: These findings indicate that measurement of urinary nitrite excretion may be a useful test to help discriminate between minimal change nephrotic syndrome and focal segmental glomerulosclerosis in children with idiopathic nephrotic syndrome. 相似文献
56.
PURPOSE: To describe the occurrence, cause, and significance of hemoptysis following thrombolytic therapy for acute myocardial infarction. PATIENTS AND METHODS: We retrospectively reviewed 2,634 patients presenting with acute myocardial infarction who received thrombolytic therapy to determine the incidence of hemoptysis. Chart and radiographic review included the type, dose, and route of thrombolytic therapy. In addition, the onset, duration, and severity of hemoptysis were recorded and correlated with radiographic and bronchoscopic findings. RESULTS: Eleven patients (0.4%) developed hemoptysis following administration of thrombolytic therapy for an acute myocardial infarction. The duration and severity had a wide range, although no patient had significant hemodynamic compromise. The source of hemoptysis was identified in only one patient who had a tongue laceration following cardiopulmonary resuscitation, and blood was seen within the oropharynx and trachea. No definitive cause was identified in all other patients. There was no correlation between the different types or doses of thrombolytic therapy and the duration or severity of hemoptysis. Chest radiographs were nonspecific and demonstrated resolution within 11 days following hemoptysis. CT of the thorax in one patient and bronchoscopy in two patients confirmed chest radiographic findings and in no patient was an underlying pulmonary abnormality identified. CONCLUSIONS: Pulmonary hemorrhage and hemoptysis are unusual complications of thrombolytic therapy in patients with acute myocardial infarction. Although hemoptysis may be the first indicator of an underlying pulmonary abnormality, we found no case in which a significant abnormality was unmasked. This study suggests that follow-up chest radiographs are recommended and further evaluation may be unnecessary if complete resolution is demonstrated. 相似文献
57.
58.
A Shibata YC Tsai MF Press BE Henderson PA Jones RK Ross 《Canadian Metallurgical Quarterly》1996,2(4):743-748
Forty-nine pairs of bilateral breast tumors (41 synchronous and 8 asynchronous cases) were examined for X-chromosome inactivation status and p53 mutations to address the issue of their clonality. Among 12 cases that were informative for the trinucleotide repeat polymorphism in exon 1 of the androgen receptor gene on the X chromosome, 3 cases were found to have different alleles of the locus inactivated in the right and left breast tumors, indicating that the two tumors arose from distinct transformed cells. Thirteen tumors (13%) from 11 women (22%) contained somatic mutations in exons 5-8 of the p53 gene. In two cases, both breast tumors harbored p53 mutations, but the specific mutations were not identical. Seven synchronous and two asynchronous cases had p53 mutations in one tumor only. A germ line p53 mutation at codon 248, one of the most common p53 mutations in Li-Fraumeni syndrome, was observed in one case. Immunohistochemical analysis of p53 protein with a monoclonal antihuman p53 antibody showed concordant positivity between the right and left tumors in three bilateral breast cancer cases. Our results suggest that at least some bilateral breast tumors originate from distinct cells, but that some bilateral breast tumors may be related through a common p53 abnormality. 相似文献
59.
60.
YC Yoo K Yoshimatsu Y Koike R Hatsuse K Yamanishi O Tanishita J Arikawa I Azuma 《Canadian Metallurgical Quarterly》1998,16(2-3):216-224
The adjuvant effect of two lipophilic derivatives of muramyl dipeptide (MDP), B30-MDP and MDP-Lys(L18), on the ability of an inactivated vaccine of B-1 virus (B-1 vaccine) to induce immune response against Hantavirus causing hemorrhagic fever with renal syndrome (HFRS) was examined. When mice were immunized subcutaneously (s.c.) twice at 2-week intervals with B-1 vaccine admixed with or without 100 micrograms mouse-1 of B30-MDP (B-1/B30-MDP) or MDP-Lys(L18) [B-1/MDP-Lys(L18)], mice immunized with B-1/B30-MDP as well as B-1/MDP-Lys(L18) showed significantly higher indirect fluorescent antibody (IFA) titers against HFRS virus than mice immunized with B-1 vaccine alone. Both mice treated with B-1/B30-MDP and B-1/MDP-Lys(L18) also exhibited significantly higher neutralizing antibody titers against HFRS virus than mice immunized with B-1 vaccine alone during 3-9 weeks after the primary immunization. The evaluation of antibody-producing cells by enzyme-linked immunospot (ELISPOT) assay on week 4 revealed that both MDP derivatives enhanced the number of HFRS virus-specific IgG1 and IgM antibody-producing cells. Furthermore, mice treated with B-1/B30-MDP as well as B-1/MDP-Lys(L18) showed a higher level of Th-2 type cytokines, IL-4 and IL-6, in sera than mice treated with B-1 alone. In an in-vitro analysis of T lymphocyte proliferation to baculovirus-expressed recombinant nucleocapsid protein (rNP) of Hantaan 76-118 strain, the splenocytes of mice treated with B-1/B30-MDP and B-1/MDP-Lys(L18) on week 4 showed a significantly higher proliferating activity than those treated with B-1 vaccine alone. In addition, when mice were immunized once with B-1 vaccine admixed with or without B30-MDP and MDP-Lys(L18) and followed by intrafootpad (i.f.) injection of B-1 vaccine on day 7, mice immunized with B-1/B30-MDP and B-1/MDP-Lys(L18) induced a higher delayed-type hypersensitivity (DTH) reaction than mice immunized with B-1 vaccine alone. These results suggest that B30-MDP and MDP-Lys(L18) are useful immunoadjuvants to enhance the ability of inactivated B-1 vaccine to induce a humoral and cellular response to HFRS virus. 相似文献