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1.
In a patient with primary lung cancer, increased accumulation of I-123-IMP was observed in a pulmonary inflammatory lesion surrounding a lung cancer which was delineated as a photon deficient area. Ga-67-citrate uptake was observed in both the inflammatory and cancerous areas. These findings suggest that I-123-IMP may have the potential to accumulate differently in a variety of pathological conditions of the lung and thus may be a clinically useful lung imaging agent.  相似文献   
2.
从人参叶中得到的两个微量皂甙成分   总被引:3,自引:0,他引:3       下载免费PDF全文
从有参叶中分离得到两种微量皂甙成分,分别为3β,12β,20(S)-三羟基达玛-24(25)-烯-(20-O-α-L-呋喃阿拉伯糖基(1→6)-β-D-吡喃葡萄糖基)-3-O-β-D-吡喃葡萄糖甙(1),和3β,12β,20(S)-三羟基达玛-24(25)-烯-(20-O-α-L-吡喃阿拉伯糖基(1→6)-β-D-吡喃葡萄糖基-3-O-β-D吡喃葡萄糖甙(2),前者为三七参甙-Fe(notoginsenoside-Fe),后者为一新的天然产物,命名为人参皂甙-Rd2(ginsenoside-Rd2)。  相似文献   
3.
Mice primed with Mycobacterium bovis bacillus Calmette-Guérin (BCG) are highly sensitive to lipopolysaccharide (LPS)-induced liver injury and lethality. We found that interleukin-15 (IL-15) transgenic (Tg) mice primed with BCG were more susceptible to LPS-induced liver injury than non-Tg mice. The numbers of CD44+ CD8+ T cells expressing intracellular gamma interferon (IFN-gamma) significantly increased in the livers of BCG-primed IL-15 Tg mice after LPS injection, and the depletion of CD8+ T cells from BCG-primed IL-15 Tg mice completely abolished the susceptibility to LPS-induced lethality. Liver T cells from BCG-primed IL-15 Tg mice produced IFN-gamma in vitro in response to LPS, which was inhibited by the addition of anti-IL-12 monoclonal antibody (MAb). In vivo treatment with anti-IL-12 MAb inhibited the appearance of CD44+ CD8+ T cells expressing intracellular IFN-gamma after LPS injection. These results suggest that the overexpression of IL-15 increases susceptibility to LPS-induced liver injury in BCG-primed mice via bystander activation of CD8+ T cells.  相似文献   
4.
It is widely accepted that the thymic microenvironment regulates normal thymopoiesis through a highly coordinated and complex series of cellular and cytokine interactions. A direct corollary of this is that abnormalities within the microenvironment could be of etiologic significance in T-cell-based diseases. Our laboratory has developed a large panel of monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial markers in the thymus. We have taken advantage of these reagents to characterize the thymic microenvironment of several genetic strains of mice, including BALB/cJ, C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcph me/Hcph me, and ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control mice, including strains of several backgrounds, have a very consistent phenotypic profile with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix. In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex and medulla at both the structural and cellular levels. These phenotypic data suggest that abnormalities in interactions between developing thymocytes and stromal cells characterize disease-prone mice.  相似文献   
5.
Lactobacilli are nonpathogenic gram-positive inhabitants of microflora. At least some Lactobacillus strains have been postulated to have health beneficial effects, such as the stimulation of the immune system. Here we examined the stimulatory effects of lactobacilli on mouse immune cells. All six heat-killed Lactobacillus strains examined induced the secretion of tumor necrosis factor alpha (TNF-alpha) from mouse splenic mononuclear cells, albeit to various degrees. When fractionated subcellular fractions of Lactobacillus casei were tested for NF-kappaB activation and TNF-alpha production in RAW264.7, a mouse macrophage cell line, the activity was found to be as follows: protoplast > cell wall > polysaccharide-peptidoglycan complex. Both crude extracts and purified lipoteichoic acids (LTAs) from two Lactobacillus strains, L. casei and L. fermentum, significantly induced TNF-alpha secretion from RAW264.7 cells and splenocytes of C57BL/6, C3H/HeN, and C3H/HeJ mice but not from splenocytes of C57BL/6 TLR2(-/-) mice. Lactobacillus LTA induced activation of c-Jun N-terminal kinase activation in RAW264.7 cells. Furthermore, in HEK293T cells transected with a combination of CD14 and Toll-like receptor 2 (TLR2), NF-kappaB was activated in response to Lactobacillus LTA. Taken together, these data suggest that LTAs from lactobacilli elicit proinflammatory activities through TLR2.  相似文献   
6.
We studied the effects of hemoglobin-vesicles modified with PEG (PEG-HbV), a type of liposome-encapsulated hemoglobin (LEH), on human platelet functions in vitro. The effect of a low concentration of PEG-HbV (Hb; 5.8 mg/dl) was assessed by examining an agonist-induced aggregation response, and that of relatively high concentrations of PEG-HbV (Hb; 0.29, 1 and 2 g/dl) by measuring the release of RANTES (Regulated upon activation, normal T-cell expressed and presumably secreted) from platelets, which is regarded as a marker of platelet activation. The preincubation of platelets with PEG-HbV at 5.8 mg/dl of Hb did not affect platelet aggregation induced by collagen, thrombin and ristocetin. The pretreatment of platelet-rich plasma (PRP) with PEG-HbV at concen trations up to 2 g/dl of Hb had no aberrant effects on the collagen-induced RANTES release. Furthermore, the collagen-induced release of RANTES from PRP was not affected by longer incubation with PEG-HbV at 2 g/dl of Hb. The basal levels of RANTES from PRP were unchanged in the presence of PEG-HbV. These results suggest that PEG-HbV, at the concentrations studied, have no aberrant effects on platelet functions in the presence of plasma.  相似文献   
7.
CA19-9 widely used as a tumor marker of the pancreas and a bile duct. There are a number of reports which describes the measured value discrepancies between RIA and non-RIA kits. RIA results also have shown lack of the linearity over 70 U/ml when the samples are diluted. The pH condition at assay reaction for RIA had been suggested as the major reason, it has been denied by the results from the same pH condition at assay reaction used by COBAS CORE CA19-9 EIA II. On the other hand, the lack of RIA antibody titer is indicated for the discordant results by changing the sample volume to reagent volume ratio in the reaction. Our further investigation also indicates that the specific Lewis blood type, i.e. Le (a-b+), shows the linearity issues by RIA. The discrepancies are not caused by the reaction pH, but the amount of the antibody used in the RIA kit is closely associated. Considering the CA19-9 antibody nature used in RIA kit, which covers broad molecular range, users need to pay more attention to setting up each laboratory's measuring range.  相似文献   
8.
PROBLEM: Recently, we reported increases in the production of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and IL-4 during the postpartum period. The present study was undertaken to investigate whether these increases might be explained by increased prolactin while breast-feeding. METHOD: Whole blood from 41 women who were breast-feeding, 13 women not breast-feeding, and 31 healthy non-pregnant women was stimulated with phorbol 12-myristate 13-acetate and ionomycin, and the levels of cytokines in the supernatant were measured by enzyme-linked immunosorbent assay. Their serum levels of prolactin were measured by enzyme immunoassay. RESULTS: Increases in IFN-gamma, IL-2, IL-4, and IL-10 production were observed in women who were breast-feeding but not in women who were not breast-feeding. Serum levels of prolactin correlated with the levels of IFN-gamma in culture supernatant. CONCLUSIONS: These results suggest that breast-feeding induces production of cytokines and that IFN-gamma production is enhanced by physiological concentrations of prolactin.  相似文献   
9.
The involvement of several cytokines in the antitumor effect induced by intrapleural (i.pl.) injection of heat-killed cells of Lactobacillus casei strain Shirota (LC 9018) in mice was investigated. Injection of LC 9018 i.pl. into Meth A fibrosarcoma (Meth A)-bearing mice not only significantly prolonged the survival of the mice, but also effectively inhibited the accumulation of malignant pleural fluid in the thoracic cavity. In the thoracic cavity of tumor-bearing mice treated with LC 9018, we observed large amounts of several cytokines including interleukin (IL)-1β, interferon (IFN)-γ, IL-12 and tumor necrosis factor (TNF)-α. Both anti-IFN-γ and anti-IL-12 monoclonal antibody (mAb) treatments partially diminished the antitumor activity of LC 9018 in vivo, while the treatment of anti-IL-1β mAb did not influence the survival of the mice. However, anti-TNF-α mAb treatment completely abolished the antitumor effect of LC 9018 in vivo, suggesting that in this model LC 9018 has a survival-prolonging effect involving certain cytokines. Moreover, i.pl. injection of mouse recombinant TNF-α into Meth A-bearing mice pretreated with anti-TNF-α mAb partially restored the survival-enhancing effect of LC 9018. These results led us to conclude that TNF-α induced by i.pl. injection of LC 9018 plays an important role in the antitumor effect of LC 9018 in vivo. Received: 22 February 1999  相似文献   
10.
In contrast to conventional assumption, recent reports propose the possibility that hematopoietic stem cells (HSCs) may have broader potential to differentiate into various cell types. Here, we tested the pluripotency of HSCs by comparing vascular lesions induced by mechanical injury after bone marrow reconstitution with total bone marrow (TBM) cells, c-Kit+ Sca-1+ Lin- (KSL) cells, or a single HSC cell (Tip-SP CD34-KSL cell, CD34- c-Kit+ Sca-1+ Lin- cell with the strongest dye-efflux activity) harboring green fluorescent protein (GFP). The lesions contained a significant number of GFP-positive cells in the TBM and KSL groups, whereas GFP-positive cells were rarely detected in the HSC group. These results suggest that transdifferentiation of a highly purified HSC seems to be a rare event, if it occurs at all, whereas bone marrow cells including the KSL fraction can give rise to vascular cells that substantially contribute to repair or lesion formation after mechanical injury.  相似文献   
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