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1.
Ultraviolet B irradiation (280 to 320 nm) of mice at the site of intradermal infection with herpes simplex virus type 2 increased the severity of the herpes simplex virus type 2 disease and decreased delayed-type hypersensitivity (DTH) responses to viral antigen. Decrease in DTH resulted from the induction of suppressor T cells, as evidenced by the ability of spleen cells from UV-irradiated mice to inhibit DTH and proliferative responses after adoptive transfer. Lymph node cells from UV-irradiated animals did not transfer suppression. DTH was suppressed at the induction but not the expression phase. Suppressor T cells were Lyt-1+, L3T4+, and their activity was antigen-specific. However, after in vitro culture of spleen cells from UV-irradiated mice with herpes simplex virus type 2 antigen, suppressor activity was mediated by Lyt-2+ cells. Culture supernatants contained soluble nonantigen-specific suppressive factors.  相似文献   
2.
Vanadate stimulated the release of lipoprotein lipase (LPL) activity from rat fat pads into the medium in a time- and dose-dependent manner. It exerted the synergetic effect with heparin. The stimulatory effects of vanadate and heparin were decreased by incubation in Na+- or Ca2+-free media but were well preserved in K+-free medium. Amiloride inhibited the vanadate-stimulated release of LPL activity in a dose-dependent manner, but did not inhibit the heparin-stimulated release of LPL activity. Colchicine, antimycin A, and carbonyl cyanide m-chlorophenylhydrazone suppressed the stimulatory effect of vanadate, but cycloheximide did not. Preincubation of the fat pads with the tetrakis (acetoxymethyl) ester of quin 2 (quin 2-AM) inhibited the vanadate-stimulatory release of LPL activity without affecting basal activity. The concentration required for half-maximal inhibition of the action of vanadate by quin 2-AM was calculated to be 39 microM, suggesting that the action of vandate was dependent on intracellular Ca2+ concentration. The heparin-stimulated release, on the other hand, was not inhibited even at higher concentrations of quin 2-AM (up to 200 microM). These findings suggest that vanadate stimulates the release of LPL activity through mechanisms of action involving amiloride-sensitive and calcium-dependent pathways with a requirement of metabolic energy.  相似文献   
3.
Twelve polyether compounds originating from dinoflagellates were tested for growth-inhibiting activities againstAspergillus niger, Penicillium funiculosum, Candida rugosa, Escherichia coli, Bacillus megaterium andStaphylococcus aureus by a paper disc method. These polyethers represent six groups of different skeletons and originate from three species;Prorocentrum lima, Dinophysis fortii andGambierdiscus toxicus. Potent antifungal activities were observed with okadaic acid and its two congeners, desulfated yessotoxin, and ciguatoxin but not with okadaic acid esters, prorocentrolide, pectenotoxin-1, yessotoxin, maitotoxin, and desulphated maitotoxin. The antifungal activities and mouse lethalities of the polyethers were markedly affected by slight modification of their structures. Antibacterial potency of the tested compounds was not significant.  相似文献   
4.
The effects of maitotoxin (MTX) on endogenous amino acid release were tested on highly purified striatal neurons differentiated in primary culture. MTX induced a large and concentration-dependent release of gamma-aminobutyric acid (GABA). This effect was abolished when experiments were performed in the absence of external Ca2+, and restored when Ca2+ ions were added after removing the MTX-containing Ca2+-free solution. MTX-induced amino acid release was not affected by 1 microM nifedipine and only slightly inhibited by 1 mM Co2+. MTX also induced a massive accumulation of 45Ca2+ in the neurons which, in contrast to the MTX-evoked GABA release, was totally blocked in the presence of 1 mM Co2+. Whereas 500 nM tetrodotoxin was without significant effect, MTX-evoked GABA release was dependent on the presence of external Na+ and sensitive to nipecotic acid, a GABA uptake inhibitor. It is concluded that, on striatal neurons, MTX induced Na+ influx only in the presence of external Ca2+. The increase in cytoplasmic Na+ ions then triggers the release of GABA.  相似文献   
5.
Fertilized eggs ofPleuronichthys cornutus were obtained by both artificial fertilization and natural spawning of laboratory-reared fish. The present paper describes in detail the early development of the fish and the rearing methods employed to provide basic information for mass production of this species. Eggs and sperm for artificial fertilization were obtained from adult fish caught in the Ariake Sound, Kyushu in November and December of 1984. Their maturation was successfully induced by intermuscular injection of pituitary homogenate of the silver carp,Hypophthalmichthys molitrix. Fertilized eggs were also obtained in 1985 by natural spawning of a broodstock kept in a tank for a year. Hatched larvae were fed successively with rotifers,Artemia nauplii and the harpacticoid copepod,Tigriopus japonicus and reared for 80 days. Ten thousand young fish of about 33 mm TL were obtained in 1984 and 1985 with the survival rate of about 17%. Ten developmental stages were defined on the basis of the morphological characteristics: A) newly hatched to 4 day old larvae, 2.7 to 4.1 mm TL (2.6 to 3.9 mmNL), yolk sac present; B) 4 to 16 day old larvae, 3.8 to 5.9 mm (3.6 to 5.6 mm), yolk resorbed, actively feeding on rotifers; C) 15 to 30 day old larvae, 6.3 to 8.3 mm (6.0 to 7.9 mm), notochord straight, hypural fin ray visible; D) 24 to 40 day old larvae, 6.7 to 9.2 mm (6.4 to 8.8 mm), caudal notochord upturned (45°); E) 28 to 45 day old larvae, 7.9 to 10.8 mm (7.5 to 10.3 mm), caudal notochord upturned (45°–90°); F) 32 to 50 day old larvae, 10.8 to 15.7 mm (8.8 to 12.8 mm BL), eyes symmetrical; G) 35 to 66 day old larvae, 13.4 to 20.0 mm (10.9 to 16.3 mm), eyes asymmetrical, but left eye not visible from the right side; H) 40 to 75 day old larvae, 13.8 to 26.2 mm (11.3 to 21.4 mm), the upper edge of left eye visible over top of the head from the right side; I) 46 to 89 day old larvae, 20.1 to 27.4 mm (16.4 to 22.4mm), left eye on the edge of the head and pupil visible from the right side; and J) juveniles of 51 day old or over, 23.6 mm or more (19.3 mm or more), metamorphosis completed. One to three inflections were found for relative growth of total length, eye diameter, upper jaw length, preanal length, and distance between the base of the pectoral fin and the anus against the notochord length or body length. Two inflections were found for body length (or notochord length)-body weight relationship. Most inflections appeared at the stages of D, F and J, corresponding to the body length of 8, 9–12 and 18–22 mm respectively.  相似文献   
6.
Antigens, recognized by human monoclonal antibody (HB4C5) generated from a lung cancer patient, were found to occur in porcine pancreas. The antigens-I and -I1 were purified from crude trypsin of porcine pancreas, only by Mono Q column chromatography, and were eluted at 260 and 300 mM NaCl in 10 mM Tris-HCI buffer, pH 7.4, respectively. These antigens differed from trypsin in molecular weight, elution pattern from the Mono Q column, and their reactivity with HB4C5. The molecular weights of the two antigens were almost the same at around 35000. These were used for serodiagnosis with an assay system based on 96-well immunoplates. The reactivities of antigens-I and -II with various sera were similar. When the reactivity of IgG in serum with antigen-II was measured, absorbance at 415 nm in the case of normal and lung cancer patients was 0.178 ± 0.056 and 0.492 ± 0.136 (p < 0.005). The rates of positive reaction in ovary, larynx, uterus, lung and liver cancers were more than 50%, but the rates in stomach and breast cancers were less than 30%. Positive reaction was hardly detected in pancreas cancer and normal controls.  相似文献   
7.
 In the present study, we carried out a functional analysis of regional lymph node lymphocytes (RLNL) from patients with lung cancer after in vitro activation by interleukin-2 (IL-2) and interleukin-12 (IL-12). IL-12 (100 U/ml) enhanced both the proliferation and cytotoxic activity of RLNL in a culture with low doses of IL-2 (5 – 10 JRU/ml). After comparing an RLNL culture with a low dose of IL-2 alone, a higher proportion of CD8+ cells and CD56+ cells and a lower proportion of CD4+ cells were found in the culture with both IL-12 and a low dose of IL-2. Such a combination of the cytokines effectively activated RLNL in terms of the expression of IL-2 receptors. In the culture condition of IL-12 and a low dose of IL-2, a synergistic effect was observed in the production of such cytokines as interferon γ, tumor necrosis factor α (TNFα), and TNFβ, as well as in tumor cytotoxicity. However, the addition of IL-12 inhibited the cytotoxicity of RLNL in the culture with a high dose of IL-2 (100 JRU/ml). This inhibition is considered to be partially due to the endogenous production of TNFα by lymphocytes, because the neutralization of TNFα bioactivity partially restored the cytotoxic activities of RLNL. Furthermore, in the presence of hydrocortisone, IL-12 synergistically enhanced the cytotoxic activity of RLNL cultured with a high dose of IL-2. These results provide useful information about the improvement of adoptive immunotherapy against cancer using RLNL. Received: 2 February 1996 / Accepted: 30 July 1996  相似文献   
8.
The expression of heparan sulfate glycosaminoglycan (HS-GAG) was examined in Xenopus embryos during the developmental stages. Chemical analysis showed the existence of HS-GAG in the 35S-labeled embryos. By western blot analysis using a specific anti-HS monoclonal antibody, HS-GAG related epitope was found after the neurulation on two protein bands, whose molecular weights were approximately 90 kDa and 100 kDa, respectively. Immunohistochemistry revealed that HS-GAG occurred exclusively in the animal hemisphere in early gastrulae, and then appeared predominantly on the sheath of the neural tube, the notochord and epithelium. To address whether HS-GAG chains contribute to Xenopus embryonic development, we eliminated the embryonic HS-GAG by injecting purified Flavobacterium heparitinases (HSase) into their blastocoels. Most of the injected embryos were aberrant in mesodermal and neural formation, and became acephalic. Histological examination showed that these embryos were completely devoid of the central nervous system and the mesodermal tissues. Neither heat-inactivated heparitinase nor chondroitinase showed such abnormality. The HS-GAG-eliminated embryos showed decreased expression of both muscular and neural-specific markers. These results suggest that HS-GAG plays an indispensable role in establishing the fundamental body plan during early Xenopus development.  相似文献   
9.
Summary Paternal age distribution for 1279 cases of Down's syndrome born in 1952–1968 was compared with the corresponding distribution for the general population, corrected for the maternal age as well as for the year of birth of the patients. Although there was no difference in the mean paternal age, the two distributions differed significantly, largely due to the excess of fathers aged 55 years and over and to the deficit of those aged 40–44 years in the patients born to mothers aged 30 years and over. The overall pattern of the relative incidence of Down's syndrome with advancing paternal age, with maternal age controlled, seems consistent with the hypothesis proposed by Stene et al. (1977). It increased from 0.8 for fathers aged 20–24 years slowly up to 1.2 for those aged 45–49 years, though with an intermediate drop to 0.8 at the age of 40–44 years, and then sharply to 2.4 for those aged 55 years and over. This rising pattern of the relative incidence with paternal age was essentially the same for the patients born in 1952–1960 and for those born in 1961–1968, although the slope was less steep in the latter than in the former group.This paper is dedicated to Professor Heinrich Schade in honor of his 70th birthday  相似文献   
10.
Summary The antitumor activity of the cell wall skeleton preparations of four species of Nocardia, N. brasiliensis strain 146, N. coeliaca strain 122, N. polychromogenes strain 6, and N. rubra, which showed potent adjuvant activity on the induction of cell-mediated cytotoxicity in allogeneic mice, was examined with the aid of EL-4 leukemia, melanoma B16, and MH-134 hepatoma in syngeneic mice. Preliminary clinical trials were performed and the results suggest that the cell wall skeleton of N. rubra, upon intrapleural injection, may be useful as an immunotherapeutic agent for patients with malignant pleurisy. The chemical properties of these cell wall skeleton preparations are described.  相似文献   
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