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21.
Marie A. Salmeron Tatsuo Morita Hidetoshi Seki Chris D. Platsoucas Kyogo Itoh 《Cancer immunology, immunotherapy : CII》1992,35(3):211-217
Summary Lymphokine production by human melanoma tumor-infiltrating lymphocytes (TIL) was studied. Uncultured TIL produced interferon (IFN), but not interleukin-2 (IL-2) or IL-4, in response to anti-CD3 mAb or IL-2. In bulk cultures, IL-2-activated TIL displaying autologous tumor-specific cytotoxicity (CTL-TIL) produced IFN in culture with medium alone, whereas IL-2-activated noncytotoxic TIL did not. Addition of anti-CD3 mAb or autologous tumor cells up-regulated IFN production in IL-2-activated TIL from 10 of 12 or 6 of 12 cases respectively. Those from 4 of 12 cases (2 CTL-TIL and 2 noncytotoxic TIL) produced IL-2 in culture with medium alone. At the clonal level, 5 (4 CD4+ and 1 CD8+) of 7 autologous tumor-specific CTL clones derived from TIL and 3 (2 CD4+ and 1 CD8+) of 7 noncytotoxic TIL clones produced IFN in culture with medium alone, which was up-regulated by adding anti-CD3 mAb. Two IFN-producing CTL clones tested produced IL-2 in 4 ×-concentrated supernatants from a 3.5-h culture with medium alone. Furthermore, 2 IFN-producing CTL clones tested expressed mRNA for both IFN and IL-2. IL-2 production and its mRNA expression were up- or down-regulated, respectively, by adding anti-CD3 mAb or autologous tumor cells. IL-4 production was not observed in culture either with medium alone or with IL-2 in any of the cells described above. Anti-CD3 mAb was required for IL-4 production in 3 of 12 IL-2-activated TIL, 2 of 6 CTL clones, and none of 5 noncytotoxic TIL clones. In summary, IFN production was characteristic of melanoma TIL. Some autologous tumor-specific CTL in TIL are suggested to be productive of IL-2 and IFN under unstimulated conditions, both being required for self-activation in an autocrine loop.This work was supported in part by grant CA-47891 from the National Cancer Institute 相似文献
22.
Benign prostatic hypertrophy and posterior urethral valves present at both extremes of the age spectrum. Both disease processes can obstruct the urinary stream and ultimately have pathophysiological effects on detrusor structure and function. The mechanisms regulating the structural reorganization of the detrusor to a mechanical outflow obstruction are not known. In an attempt to identify maturational differences in myocyte ultrastructure and consequent effects these might have in modifying the response of the detrusor to mechanical stimulus, we studied differences in dynamic nuclear-cytoskeletal interactions in detrusor tissue in an animal model. Using a drug which specifically severs actin, cytochalasin D (CD), as an intracellular mechanical stimulus, we measured changes in nuclear area and the rate of DNA synthesis in detrusor myocytes from young (2-3 week) and old (8-12 mon) guinea pigs. We found that there were age specific differences to intracellular mechanical stimuli in detrusor muscle. Nuclei of myocytes from young animals showed elastic recoil on severing the cell actin matrix and the tissue from young animals increased replicative DNA synthesis with an intracellular stimulus. In contrast, nuclear shape changes in myocytes from old animals suggested less elasticity, and there was no increase in DNA synthesis with disruption of the cell actin matrix. Anti-alpha-smooth muscle actin antibody and rhodamine phalloidin staining of actin in cytochalasin D treated primary explants of detrusor myocytes showed dose dependent disruption of the actin component of the cytoskeleton. These results suggest that there are fundamental modifications in detrusor myocyte ultrastructure with age. These maturational changes might result in differences in the pathophysiological and structural reorganization of the detrusor in response to outflow obstruction in infancy and adulthood. Furthermore, they suggest that 1) a tensile equilibrium exists between the myocyte nucleus and cytoskeleton; 2) there appears to be a decrease in myocyte nuclear elasticity with ageing; 3) release of nuclear template restrictions increases activity of DNA polymerase alpha in young, but not old, detrusor myocytes; and 4) mechanico-chemical signal transduction in detrusor myocytes may be mediated via the cytoskeleton. In addition, based on previous reports of actin within the nucleus, the results suggest that 1) nuclear actin may have a homeostatic structural role, maintaining the tensile equilibrium between nucleus and cytoskeleton, and 2) integrity of nuclear actin may function to maintain the spatial template restriction on DNA polymerase alpha activity. 相似文献
23.
M Shibata T Seki T Yoshizu H Saito T Tajima 《Plastic and reconstructive surgery》1991,88(1):102-9; discussion 110
Free nonvascularized toenail grafts have been used to reconstruct congenital or traumatic nail defects of the thumb or finger. Unfortunately, these transfers often result in deformity or atrophy. To avoid these undesirable results, microsurgical free vascularized toenail transfer was performed in 10 patients, 3 for congenital nail absence and 7 for traumatic nail defects. Patient age averaged 17 years (range 2 to 32 years). In contrast with previous reports, the whole big or second toenail complex without pulp was used in reconstruction. All 10 nails were successfully transferred with complete survival. No digits required reexploration. There were no donor- or recipient-site problems. Follow-up averaged 3 years, with a range of 14 months to 5 years and 4 months. Appropriate nail growth occurred in the congenital patients. No atrophy of the nail complex was found as long as sufficient bony support was present (9 of 10 cases). Whole free vascularized toenail transfers for reconstruction of congenital and traumatic nailbed defects achieve excellent aesthetic results while maintaining normal hand function. 相似文献
24.
We found that the incidence of spontaneous myeloid leukemia in C3H/He male mice was less than 1%, but it could be increased considerably by total-body X irradiation. The induction of myeloid leukemia was seen to increase after doses from 0.47 Gy (3%) to 2.84 Gy (23.9%), and then decrease after a dose of 4.73 Gy (13.6%). The administration of prednisolone acetate (synthesized glucocorticoid) after irradiation resulted in a significant increase in the incidence of myeloid leukemia from 23.9 to 38.5% after a dose of 2.84 Gy; however, corticosterone, a glucocorticoid secreted by cells, did not have such an enhancing effect. 相似文献
25.
A repeating unit of the DYZ1 family on the human Y chromosome consists of segments with partial male-specificity 总被引:1,自引:0,他引:1
Y Nakagome S Nagafuchi S Seki Y Nakahori T Tamura M Yamada M Iwaya 《Cytogenetics and cell genetics》1991,56(2):74-77
An average-sized human Y chromosome contains about 3,000 copies of the repeating DNA family DYZ1. A major repeating unit of the family, pHY10, has been cloned and an entire 3,564-bp sequence has already been determined by Nakahori et al. (1986). In the present study, pHY10 was divided into six consecutive segments, A to F, which were independently amplified by the PCR technique to see if they were strictly male-specific. pHY10 appears to consist of segments of various male-specificity. The B segment was apparently male-specific; however, the use of additional techniques (Southern-blot analysis or second PCR amplification in combination with the standard PCR) revealed homologous sequences in some females. None of the six segments of pHY10 may be male-specific in a strict sense. Different segments appear to be conserved during evolution to different extents. The 323-bp E segment appears to be the least conserved and to be responsible for the generation of most variations within the DYZ1 family. 相似文献
26.
Yoshihiro Toh Akiko Mizutani Fuminori Tokunaga Tatsushi Muta Sadaaki Iwanaga 《Cell and tissue research》1991,266(1):137-147
Summary The structure of hemocytes in the normal state and during blood coagulation, and the intracellular localization of three clotting factors and two antimicrobial factors were examined in the Japanese horseshoe crabTachypleus tridentatus. Two types of hemocytes were found in the circulating blood: non-granular and granular hemocytes. The latter contained numerous dense granules classed into two major types: L- and D-granules. The L-granules were larger (up to 1.5 m in diameter) and less electron-dense than the D-granules (less than 0.6 m in diameter). The L-granules contained three clotting factors and one antimicrobial factor, whereas the D-granules exclusively contained the other antimicrobial factor. After treatment with endotoxin, the L-granules were released more rapidly than the D-granules, although almost all granules were finally exocytosed. The granular hemocyte possessed a single Golgi complex; possible precursor granules of L-granules and D-granules contained tubular and condensed dense material, respectively. These data are discussed in relation to the self-defense mechanisms of the horseshoe crab. 相似文献
27.
Rubredoxin as an intermediary electron carrier for nitrate reduction by NAD(P)H in Clostridium perfringens 总被引:2,自引:0,他引:2
The NAD(P)H-dependent nitrate reductase system in Clostridium perfringens was reconstituted with rubredoxin (Rd), nitrate reductase (NaR), and an unadsorbed fraction, on a DEAE-cellulose column, of the extract (designated as fraction A), under nitrogen gas. Ferredoxin in place of Rd was not effective as an electron carrier in this reconstituted system. NAD(P)H-dependent nitrate reducing activity was also obtained by replacing fraction A with ferredoxin-NADP+ reductase from spinach. We propose the following scheme for the electron transfer in this NAD(P)H dependent nitrate reduction system. NAD(P)H----NAD(P)H-Rd reductase----Rd----NaR----NO3-. 相似文献
28.
Detection and characterization of a novel factor that stimulates DNA polymerase alpha 总被引:2,自引:0,他引:2
A novel factor that stimulates DNA polymerase alpha activity on poly(dA) X oligo(dT) has been identified and partially purified from mouse FM3A cells. The assay system for the factor contained poly(ethylene glycol) 6000. The activities of DNA polymerase alpha on poly(dA) X oligo(dT) in the presence and absence of the stimulating factor were increased greatly by the addition of poly(ethylene glycol). Stimulation by the factor was observed at all the primer to template ratios tested from 0.01 to 0.3. The highest activity was observed at the ratio of 0.05, corresponding to about 3.3 primers on one template in the presence of the factor. The concentration of DNA polymerase alpha used in the assay affected the stimulation by the factor, and the stimulation became more prominent at concentrations of the enzyme lower than 0.04 unit per assay. The stimulating factor lowered the Km value of DNA polymerase alpha for the template-primer, though they had no effect on the Km value for dTTP substrate. The results of product analysis suggested that the stimulation by the factor is mainly due to the increase in the initiation frequency of DNA synthesis from the primers. The stimulating factor specifically stimulated DNA polymerase alpha but not DNA polymerases beta and gamma. Furthermore, the factor formed a complex with DNA polymerase alpha under a certain condition. 相似文献
29.
30.
A double-stranded RNA plasmid which confers the superkiller phenotype was transferred into a wine yeast (Montrachet strain 522) and its leucine-requiring derivative (strain 694) by cytoduction, using the protoplast fusion technique. The killer wine yeast constructed completely suppressed the growth of killer-sensitive strains of Saccharomyces cerevisiae in yeast extract-peptone-glucose medium at pH 4.5, whereas the killer effect was somewhat decreased at pH 3.5. The wine yeast harboring the killer factor also inhibited the growth of killer-sensitive cells satisfactorily when it was grown in grape juice. 相似文献