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921.
Paul L. Black Hamblin Phillips Henry R. Tribble Robin Pennington Mark schneider James E. Talmadge 《Cancer immunology, immunotherapy : CII》1993,37(5):299-306
The mechanism of therapeutic activity for recombinant murine interferon-(rMu IFN) in the treatment of metastatic disease was investigated by comparing effector cell augmentation with therapeutic activity in mice bearing experimental lung metastases (B16-BL6 melanoma). Effector cell functions in spleen, peripheral blood, and lung (the tumor-bearing organ) were tested after 1 week and 3 weeks of rMu IFN administration (i.v. three times per week). Natural killer (NK), lymphokine-activated killer (LAK), cytolytic T lymphocyte (CTL) activities against specific and nonspecific targets, and macrophage tumoristatic activity were measured. rMu IFN demonstrated immunomodulatory activity in most assays of immune function. The optimal therapeutic protocol of rMu IFN (2.5×106 U/kg, three times per week) prolonged survival and decreased the number of pulmonary metastatic foci. This therapeutic activity was correlated with specific CTL activity from pulmonary parenchymal mononuclear cells (PPMC), but not from spleen or blood. Macrophage tumoristatic activity in PPMC also correlated with therapeutic activity, but activity in alveolar macrophages did not. However, therapeutic activity did not correlate with NK or LAK activity at any site. These results demonstrate that the optimal therapeutic protocol is the same as the optimal immunomodulatory dose for pulmonary CTL and macrophage activities. Furthermore, while immunological monitoring may help to optimize treatment protocols, current monitoring procedures that use readily accessible sites, particularly peripheral blood, may not accurately predict the therapeutic efficacy of biological response modifiers in clinical trials.By acceptance of this article, the publisher or recipient acknowledges the right of the US. Government to retain a nonexclusive, royalty-free license in and to any copyright covering the articleThis research was sponsored by the DHHS, under contract N01-23910 with Program Resources Inc. The contents of this publication do not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government 相似文献
922.
Riccardo Pierantoni Mauro D'Antonio Silvia Fasano 《Environmental Biology of Fishes》1993,38(1-3):187-196
Synopsis The tetrapod hypothalamus-pars distalis axis contains a blood portal system. Contrarily, elasmobranchs appear to lack a direct vascular supply from the hypothalamus to the ventral lobe of the pituitary where gonadotropic activity resides. The hypothalamus contains GnRH immunoreactivity and GnRH causes an increase in plasma gonadal steroids, perhaps via ventral lobe stimulation. Therefore, the question arises as to how GnRH reaches the pituitary. We suggest that the general circulation route might be practicable. Indeed, in the plasma of the electric ray,Torpedo marmorata, a major early eluting form has been detected using high performance liquid chromatography coupled with region specific radioimmunoassay. The presence of GnRH in the blood may allow the molecule to reach the gonads and to act there by direct mechanisms. Intragonadal levels of steroids may have a paracrine and/or autocrine role in the regulation of steroidogenesis in the testis and in the development f specific germinal cell stages. Particularly, the zonated morphology of the testis supports the concept of a diverse environment for different spermatogenic stages. Finally, gonadal steroids may feed back to affect pituitary activity. 相似文献
923.
Rumen contents as a reservoir of enterohemorrhagic Escherichia coli 总被引:11,自引:0,他引:11
Mark A. Rasmussen William C. CrayJr. Thomas A. Casey Shannon C. Whipp 《FEMS microbiology letters》1993,114(1):79-84
Abstract We investigatedthe role of the rumen fermentation as a barries to the foodborne pathogen, Escherichia coli O157:H7. Strains of E. coli , including several isolates of O157:H7, grew poorly in media which simulated the ruminal environment of a well-fed animal. Strains of E. coli O157:H7 did not display a superior tolerance to ruminal conditions which may facilitate their colonization of the bovine digestive tract. Unrestricted growth of E. coli was observed in rumen fluid collected from fasted cattle. Growth was inhibited by rumen fluid collected from well-fed animals. Well-fed animals appear less likely to become reservoirs for pathogenic E. coli . These results have implications for cattle slaughter practices and epidemiological studies of E. coli O157:H7. 相似文献
924.
甲烷作为全球第二大温室气体,是典型的可再生清洁能源,也是碳循环中的重要物质组成。大气中约74%的甲烷由产甲烷古菌和其他微生物的互营产生,种间电子传递(interspecies electron transfer, IET)是微生物菌群降低热力学能垒、实现互营产甲烷的核心过程。IET可分为间接种间电子传递(mediated interspecies electron transfer,MIET)和直接种间电子传递(direct interspecies electron transfer, DIET)两种类型,其中MIET依赖氢气、甲酸等载体完成电子的远距离传输,而DIET则依赖导电菌毛、细胞色素c等膜蛋白,通过微生物的直接接触实现电子传递。本文将从IET的研究历程出发,从电子传递机制、微生物种类、生态多样性等方面对微生物互营产甲烷过程中的两种IET类型进行比较,最后对未来待探索的方向进行展望。本综述有助于加深对微生物互营产甲烷过程中IET的理解,为解决由甲烷引发的全球气候变暖等生态问题提供理论支撑。 相似文献
925.
脉叶罗汉松化学成分的研究 总被引:2,自引:0,他引:2
从脉叶罗汉松(Podocarpus neriifolius D.Don)的枝叶中分离到11种化合物,根据光谱数据和物理常数测定,分别鉴定为正三十四烷醇(1)、β-谷甾醇硬脂酸酯(2)、β-谷甾醇(3)、金松双黄酮(sciadopitysin,3)、罗汉松双黄酮 B(podocarpusflavone B,12)、罗波斯塔黄酮-7″-甲醚(robustaflavone-7″-methyl ether,13)罗汉松双黄酮 A(podocarpusflaveone A,14)、罗波斯塔黄酮(robustaflavone,15)、对羟基苯甲酸(p-hydroxyl-benzoic acid,16)、2″-O-鼠李糖扫帚黄甙(2″-O-rhamnosylscoparin,23)和2″-O-鼠李糖牡荆黄甙(2″-O-rhamnosylvitexin,24)。其中,化合物23和24为首次从罗汉松科分得的化合物,化合物8、13和15首次从该植物分离到。 相似文献
926.
JANINA KACZANOWSKA LEONORA BUZANSKA MAREK OSTROWSKI 《The Journal of eukaryotic microbiology》1993,40(6):747-754
Microtubular basal bodies and epiplasm (membrane skeleton) are the main components of the cortical skeleton of Tetrahymena. The aim of this report was to study functional interactions of basal bodies and epiplasm during the cell cycle. The cortex of Tetrahymena cells was stained with anti-epiplasm antibody. This staining produced a bright epiplasmic layer with a dark pattern of unstained microtubular structures. The fluorescence of the anti-epiplasm antibody disappeared at sites of newly formed microtubular structures, so the new basal body domains and epiplasmic layer could be followed throughout the cell cycle. Different patterns of deployment of new basal bodies were observed in early and advanced dividers. In advanced dividers the fluorescence of the epiplasmic layer diminished locally within the forming fission line where the polymerization of new basal bodies largely extincted. In wild type Tetrahymena, the completion of the micronuclear metaphase/anaphase transition was associated with a transition from the pattern of new basal body deployment and epiplasm staining of the early divider to the pattern of the advanced dividers. The signal for the fission line formation in Tetrahymena (absent in cdaA1 Tetrahymena mutationally arrested in cytokinesis) brings about 1) transition of patterns of deployment of basal bodies and epiplasmic layer on both sides of the fission line; and 2) coordination of cortical divisional morphogenesis with the micronuclear mitotic cycle. 相似文献
927.
928.
Upgrading the genome of an elite japonica rice variety Kongyu 131 for lodging resistance improvement
Chen Wang Xiaomin Feng Qingbo Yuan Kangxue Lin Xiaohui Zhang Li Yan Jianzong Nan Wenqi Zhang Rongsheng Wang Lihong Wang Qian Xue Xiaowen Yang Zhixia Liu Shaoyang Lin 《Plant biotechnology journal》2023,21(2):419-432
Developing a new rice variety requires tremendous efforts and years of input. To improve the defect traits of the excellent varieties becomes more cost and time efficient than breeding a completely new variety. Kongyu 131 is a high-performing japonica variety with early maturity, high yield, wide adaptability and cold resistance, but the poor-lodging resistance hinders the industrial production of Kongyu 131 in the Northeastern China. In this study, we attempted to improve the lodging resistance of Kongyu 131 from perspectives of both gene and trait. On the one hand, by QTL analysis and fine mapping we discovered the candidate gene loci. The following CRISPR/Cas9 and transgenic complementation study confirmed that Sd1 dominated the lodging resistance and favourable allele was mined for precise introduction and improvement. On the other hand, the Sd1 allelic variant was identified in Kongyu 131 by sequence alignment, then introduced another excellent allelic variation by backcrossing. Then, the two new resulting Kongyu 131 went through the field evaluation under different environments, planting densities and nitrogen fertilizer conditions. The results showed that the plant height of upgraded Kongyu 131 was 17%–26% lower than Kongyu 131 without penalty in yield. This study demonstrated a precise and targeted way to update the rice genome and upgrade the elite rice varieties by improving only a few gene defects from the perspective of breeding. 相似文献
929.
930.
Xiaoyu Yi Chao Zhang Baojie Liu Guojun Gao Yaqi Tang Yongzheng Lu Zhifang Pan Guohui Wang Weiguo Feng 《Journal of cellular and molecular medicine》2023,27(3):403-411
Prostate cancer (PCa) is one of the most common malignancies in men. Ribosomal protein L22-like1 (RPL22L1), a component of the ribosomal 60 S subunit, is associated with cancer progression, but the role and potential mechanism of RPL22L1 in PCa remain unclear. The aim of this study was to investigate the role of RPL22L1 in PCa progression and the mechanisms involved. Bioinformatics and immunohistochemistry analysis showed that the expression of RPL22L1 was significantly higher in PCa tissues than in normal prostate tissues. The cell function analysis revealed that RPL22L1 significantly promoted the proliferation, migration and invasion of PCa cells. The data of xenograft tumour assay suggested that the low expression of RPL22L1 inhibited the growth and invasion of PCa cells in vivo. Mechanistically, the results of Western blot proved that RPL22L1 activated PI3K/Akt/mTOR pathway in PCa cells. Additionally, LY294002, an inhibitor of PI3K/Akt pathway, was used to block this pathway. The results showed that LY294002 remarkably abrogated the oncogenic effect of RPL22L1 on PCa cell proliferation and invasion. Taken together, our study demonstrated that RPL22L1 is a key gene in PCa progression and promotes PCa cell proliferation and invasion via PI3K/Akt/mTOR pathway, thus potentially providing a new target for PCa therapy. 相似文献