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1.
Occluded virions of the Bombyx mori nuclear polyhedrosis virus were efficiently liberated from polyhedra by dissolution with the silkworm gut juice. The liberated virions were purified by sucrose density gradient centrifugation and the bands of enveloped virions were observed in the gradients. There was no functional difference between the gut juice-liberated and the carbonate-liberated virions. Disruption of enveloped virions by the gut juice was observed, but the formation of nucleocapsids from the degradation of the occluded virions was not detected. High yields of the enveloped virions from the polyhedra dissolved by the gut juice was obtained by separating the virions through sucrose density gradient centrifugation immediately after the dissolution of the polyhedra. Many factors, e.g., rearing seasons, silkworm strains, and rearing conditions, affect the polyhedra-dissolving property of the larval gut juice.  相似文献   
2.
Akt is known to be activated in the rheumatoid synovial tissues. We examined here functional role of Akt during tumor necrosis factor-related apoptosis inducing ligand (TRAIL)-mediated apoptosis in rheumatoid synovial cells. Rheumatoid synovial cells in vitro were rapidly committed to apoptosis in response to TRAIL in mitochondria-dependent manner whereas Akt and extracellular signal-regulated kinase (ERK) were also phosphorylated. TRAIL-mediated apoptosis in synovial cells was significantly increased through inactivation of Akt by LY294002, however, that process was not so changed by adding ERK inhibitor, PD98059. Platelet-derived growth factor (PDGF) clearly phosphorylated both Akt and ERK in synovial cells, and PDGF pretreatment markedly suppressed TRAIL-mediated synovial cell apoptosis. The use of not PD98059 but LY294002 abrogated PDGF-mediated inhibitory effect toward TRAIL-induced apoptosis in synovial cells. The above protective effect of Akt was confirmed by the use of short interfering RNA (siRNA)-directed inhibition of Akt. Our data suggest that Akt is an endogenous inhibitor during TRAIL-mediated synovial cell apoptotic pathway, which may explain that synovial cells in situ of the rheumatoid synovial tissues are resistant toward apoptotic cell death in spite of death receptor expression.  相似文献   
3.
We investigated the effect of human beta-amyloid precursor protein (APP) on rat primary cerebral cortical neurons cultured in a serum-free medium. Two secretory APP species (APP667 and APP592) with and without the protease inhibitor domain were produced by COS-1 cells transfected with APP cDNAs, which encode the N-terminal portions of APP770 and APP695. Both highly purified APP species, when added to the medium, enhanced neuronal survival and neurite extension in a dose-dependent manner with a maximum effect at approximately 100 nM. These results suggest that secreted forms of APP have trophic activity for cerebral cortical neurons.  相似文献   
4.
Research on the soft coral genus Sarcophyton extends over a wide range of fields, including marine natural products and the isolation of a number of cembranoid diterpenes. However, it is still unknown how soft corals produce this diverse array of metabolites, and the relationship between soft coral diversity and cembranoid diterpene production is not clear. In order to understand this relationship, we examined Sarcophyton specimens from Okinawa, Japan, by utilizing three methods: morphological examination of sclerites, chemotype identification, and phylogenetic examination of both Sarcophyton (utilizing mitochondrial protein-coding genes MutS homolog: msh1) and their endosymbiotic Symbiodinium spp. (utilizing nuclear internal transcribed spacer of ribosomal DNA: ITS- rDNA). Chemotypes, molecular phylogenetic clades, and sclerites of Sarcophyton trocheliophorum specimens formed a clear and distinct group, but the relationships between chemotypes, molecular phylogenetic clade types and sclerites of the most common species, Sarcophyton glaucum, was not clear. S. glaucum was divided into four clades. A characteristic chemotype was observed within one phylogenetic clade of S. glaucum. Identities of symbiotic algae Symbiodinium spp. had no apparent relation to chemotypes of Sarcophyton spp. This study demonstrates that the complex results observed for S. glaucum are due to the incomplete and complex taxonomy of this species group. Our novel method of identification should help contribute to classification and taxonomic reassessment of this diverse soft coral genus.  相似文献   
5.
BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferative disorder of Langerhans cells, but the nature of LCH, whether reactive, benign, or malignant and neoplastic, is controversial. We encountered a case of LCH showing a malignant phenotype initially localized in the skin of an elderly woman. Since there is no other report on the cytologic appearance of primary cutaneous LCH or on LCH with a malignant phenotype, we compared the cytologic features of this case with those of benign cases at other sites reported in the literature. CASE: A 74-year-old woman presented with a gradually enlarging and partially ulcerated skin lesion expanding both sides of her right hand. On histologic and ultrastructural analyses of surgically resected tissue, we diagnosed the lesion as Langerhans cell histiocytosis originating in the skin. Although the patient had no recurrence or metastases for six months after surgical resection of the primary skin lesion and radiation therapy, the tumor extended multisystemically, and the patient died of multiple organ failure 14 months after the initial diagnosis. CONCLUSION: Imprint and scrape cytology of multiple skin lesions six months after surgery was useful in immediately diagnosing the recurrent LCH. The tumor cells had indented, twisted or grooved nuclei, and some had intranuclear inclusions. Immunocytochemically the cells were positive for CD1a and S-100 protein. Numerous eosinophils were seen in the background.  相似文献   
6.
A study was undertaken of the application of the avidin-biotin-peroxidase complex (ABC) method to the monoclonal antibody MAbs staining of mononuclear cells in hematologic and cytodiagnostic materials. Satisfactory cell morphology and immunoreactivity of surface antigens were observed when the slides were fixed in 80% acetone in phosphate-buffered saline or in 60% acetone in 0.03 M citric acid buffer solution (pH 5.4). Unstained air-dried preparations could be preserved for two weeks at room temperature in a desiccator and for one year at -70 degrees C after fixation. An excellent immunoreaction, even with a weak surface antigen, was observed by inhibition of endogenous peroxidase after the secondary antibody reaction; reactions of weak antigens tended to be obscured when the inhibition was performed before the first antibody reaction. Use of the Giemsa stain as a counterstain made it possible to readily observe the cell morphology; therefore, white blood cell analysis could be performed simultaneously when peripheral blood smears were studied. The positive rate of immunoreaction by an immunofluorescent method was well correlated with that obtained by the ABC method. The ABC method proved to be an excellent immunocytochemical technique for detecting cell surface antigens with high sensitivity and specificity; furthermore, it is useful for cell morphology studies and yields permanent preparations.  相似文献   
7.
Hydrogen and a bioflocculant could be produced simultaneously by anaerobic culture of Enterobacter sp. BY-29. For production of hydrogen and the bioflocculant by cell culture of the bacterium in batch cultures, cultivation at 37 °C in a medium containing glucose as a carbon source and Polypepton as a nitrogen source was found to be suitable. In continuous production of hydrogen and the bioflocculant by cell culture or immobilized cells of the bacterium, the hydrogen production rate and hydrogen yield by the immobilized cells on porous glass beads in stirred and column reactors were higher than those by the cell culture in a stirred reactor. However, production of the bioflocculant by the cell culture was superior to that by the immobilized cells in continuous production.  相似文献   
8.
A subpopulation of lymphocytes forming rosettes with autologous erythrocytes was studied on peripheral blood and thyroid tissues obtained from the patients with various thyroid diseases. The mean (+/-S.D.) percentage of autorosette-forming cells (ARFC) was 10.1(+/-5.5)% in the peripheral blood from patients with hyperthyroid Graves' disease, which was higher than that in normal subjects (5.6 +/- 2.8%), while the levels of ARFC in the peripheral blood from euthyroid patients with Graves' disease under treatment and Hashimoto's thyroiditis did not significantly differ from the normal level. The mean percentages of ARFC in the thyroid tissues from patients with Graves' disease and Hashimoto's thyroiditis were 14.7(+/-8.5) and 13.3(+/-7.8)%, respectively, which were higher than those in the peripheral blood from the same patients. Most of these cases with abnormally high levels of ARFC were accompanied with the abnormally low T cell to B cell ratios. The microscopic examination of the cytological materials from these patients showed an increased number of large stimulated lymphoid cells or lymphoblasts as compared with those who had few ARFC. These results suggest an increase in an activated T cell subset in the circulation and/or in the thyroid tissue, which is probably caused by active immune response to some stimuli.  相似文献   
9.
Two environments, soils and silkworm ( Bombyx mort )-breeding farms, in Kumamoto Prefecture, Japan, were explored for the comparative analysis of the frequency and the flagellar (H) serotype flora of Bacillus thuringiensis. This organism was found in 39.3% of the sericulture farms and 18.5% of the silkworm litter samples. The frequency of B. thuringiensis was 4.5% among the populations of the Bacillus cereus/B. thuringiensis group in silkworm-breeding insectaries. The predominant H serotype detected in silkworm litters was 4ac (35.6%), followed by serotypes 3abc (20.0%), 8ab (13.3%), 4ab (13.3%) and 7 (2.2%). The majority (87.1%) of sericulture-derived isolates exhibited larvicidal activity against the silkworm and/or the mosquito, Aedes aegypti. Of soil samples examined, 8.1% contained B. thuringiensis. The frequency of B. thuringiensis colonies was 0.6% among soil populations of the B. cereus/B. thuringiensis group. Of 22 soil isolates, 14 were assigned to five H serotypes: 10, 17, 18, 21 and 29. Most soil isolates showed no insecticidal activity against B. mori and A. aegypti , but two, belonging to H serotype 10 and an undescribed serotype, exhibited moderate larvicidal activity against A. aegypti.  相似文献   
10.
Y. Aratake, K. Marutsuka, K. Kiyoyama, T. Kuribayashi, T. Miyamoto, K. Yakushiji, S. Ohno, Y. Miyake, T. Sakaguchi, T. K. Kobayashi, A. Okayama, K. Tamura and E. Ohno
EMMPRIN (CD147) expression and differentiation of papillary thyroid carcinoma: implications for immunocytochemistry in FNA cytology Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) and its induced matrix metalloproteinases (MMPs) play a crucial role in tumour progression, invasion and metastasis. EMMPRIN expression has been demonstrated in several tumours, but its expression profile in thyroid cancer remains unclear. Methods: We evaluated the expression profile of EMMPRIN at various stages of differentiation of thyroid carcinoma, including 20 cases of well‐differentiated papillary carcinoma (WDPC), 15 cases of papillary carcinoma with a poorly differentiated carcinoma component (PC/PDC) and four cases with an undifferentiated carcinoma (UDC) component, using paraffin‐embedded sections for immunohistochemical stains. Also, we used 32 fine needle aspiration cytology and imprint smears from the same cases for immunocytochemical stains. The staining results were evaluated with a scoring system. Results: Immunohistochemical staining showed that EMMPRIN expression was absent or weak in almost all WDPC specimens, whereas it was moderate or strong in PDC and UDC components. In tumours that showed a gradual morphological transformation from WDPC to PDC components, the expression of EMMPRIN was progressively stronger from the areas of WDPC to those of PDC. WDPC, PC/PDC and UDC had expression scores of 4.9, 45.0 and 245.7, respectively. Results of immunocytochemical staining showed almost the same staining profile as those of immunohistochemical staining. The cytological atypia of EMMPRIN‐positive cells was greater than that of negative cells. Conclusion: These results indicated that EMMPRIN expression correlates significantly with the degree of dedifferentiation of thyroid carcinoma. This study demonstrates the feasibility of expression of EMMPRIN using fine needle aspiration samples. Therefore, immunocytochemical analysis of EMMPRIN may be a novel aid to evaluate the differentiation of thyroid carcinoma.  相似文献   
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