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181.
Yvonne J. Rosenberg 《Cellular immunology》1981,61(2):416-424
In order to delineate the various roles of T cells in B-cell activation, mice were exposed to a variety of specific or nonspecific T-cell stimuli including mitogens, e.g., concanavalin A, adjuvants, e.g., complete Freund's adjuvant, and colchicine plus nonimmunogenic doses of antigen, anti-lymphocyte serum, and pathogens and their spleens analyzed for total class-specific immunoglobulin-secreting cells as indicators of helper cell generation. The results demonstrate that, depending on the mode of stimulation, markedly different Ig-secreting cell response patterns were induced, differing with respect to their kinetics and the isotype induced. In contrast to polyclonal T-cell stimuli such as concanavalin A and 17X lethal malaria which induced increases in all classes of Ig-recruiting cells, injection of many T-cell-activating agents resulted in the selective production of IgG clones in particular IgG 1. Such findings are discussed in terms of the different mechanisms of T-cell help and provide further evidence for functional heterogeneity in the T-helper-cell pool. 相似文献
182.
Kenneth Pomerantz Yvonne Maddox Franco Maggi Estelle Ramey Peter Ramwell 《Life sciences》1980,27(13):1233-1236
The stable breakdown product of prostacyclin, 6-keto-PGF1α, was estimated in plasma samples after incubation with rat aortic rings. The 6-keto-PGF1α concentration obtained with the male aortae was two-fold higher than that of the female. Ovariectomy markedly increased 6-keto-PGF1α six-fold, but castration had no effect. Estradiol and progesterone treatment of the ovariectomized female suppressed (by 50%) and enhanced (two-fold) 6-keto-PGF1α. Testosterone was without effect in gonadectomized males and females. Castrate males did not respond to gonadal steroid treatment. 相似文献
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Yvonne Dimberg 《Bioelectromagnetics》1995,16(4):263-267
C57/B1 mice were exposed during pregnancy (gestation days 0–19) to a 20 kHz magnetic field (MF). The asymmetric sawtooth-wave form magnetic field in the exposed racks had a flux density of 15 μT (peak to peak). After 19 days, the exposure was terminated, and the mice were housed individually under normal laboratory conditions. On postnatal day (PD) 1, PD21, and PD308, various neurochemical markers in the brains of the offspring were investigated and the brains weighed. No significant difference was found in the whole brain weight at PD1 or PD21 between exposed offspring and control animals. However, on PD308, a significant decrease in weight of the whole brain was detected in exposed animals. No significant differences were found in the weight of cortex, hippocampus, septum, or cerebellum on any of the sampling occasions, nor were any significant differences detected in protein-, DNA-level, nerve growth factor (NGF), acetylcholine esterase- (AChE), or 2′,3′-cyclic nucle-otide 3′-phosphodiesterase- (CNP; marker for oligodendrocytes) activities on PD21 in cerebellum. Cortex showed a more complex pattern of response to MF: MF treatment resulted in a decrease in DNA level and increases in the activities of CNP, AChE, and NGF protein. On PD308, the amount of DNA was significantly reduced in MF-treated cerebellum and CNP activity was still enhanced in MF-treated cortex compared to controls. Most of the effects of MF treatment during the embryonic period were similar to those induced by ionizing radiation but much weaker. However, the duration of the exposure required to elucidate the response of different markers to MF seems to be greater and effects appear later during development compared to responses to ionizing radiation. © 1995 Wiley-Liss, Inc. 相似文献
186.
Wanglin Liu Mingyue Cheng Jinman Li Peng Zhang Hang Fan Qinghe Hu Maozhen Han Longxiang Su Huaiwu He Yigang Tong Kang Ning Yun Long 《基因组蛋白质组与生物信息学报(英文版)》2020,18(6):696-707
The gut microbiota of intensive care unit (ICU) patients displays extreme dysbiosis associated with increased susceptibility to organ failure, sepsis, and septic shock. However, such dysbiosis is difficult to characterize owing to the high dimensional complexity of the gut microbiota. We tested whether the concept of enterotype can be applied to the gut microbiota of ICU patients to describe the dysbiosis. We collected 131 fecal samples from 64 ICU patients diagnosed with sepsis or septic shock and performed 16S rRNA gene sequencing to dissect their gut microbiota compositions. During the development of sepsis or septic shock and during various medical treatments, the ICU patients always exhibited two dysbiotic microbiota patterns, or ICU-enterotypes, which could not be explained by host properties such as age, sex, and body mass index, or external stressors such as infection site and antibiotic use. ICU-enterotype I (ICU E1) comprised predominantly Bacteroides and an unclassified genus of Enterobacteriaceae, while ICU-enterotype II (ICU E2) comprised predominantly Enterococcus. Among more critically ill patients with Acute Physiology and Chronic Health Evaluation II (APACHE II) scores > 18, septic shock was more likely to occur with ICU E1 (P = 0.041). Additionally, ICU E1 was correlated with high serum lactate levels (P = 0.007). Therefore, different patterns of dysbiosis were correlated with different clinical outcomes, suggesting that ICU-enterotypes should be diagnosed as independent clinical indices. Thus, the microbial-based human index classifier we propose is precise and effective for timely monitoring of ICU-enterotypes of individual patients. This work is a first step toward precision medicine for septic patients based on their gut microbiota profiles. 相似文献
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Jin Cui Xiaoqun Li Sicheng Wang Yiming Su Xiao Chen Liehu Cao Xin Zhi Zili Qiu Yao Wang Hao Jiang Biaotong Huang Fang Ji Jiacan Su 《Journal of cellular and molecular medicine》2020,24(11):6149-6161
Bone loss (osteopenia) is a common complication in human solid tumour. In addition, after surgical treatment of gynaecological tumour, osteoporosis often occurs due to the withdrawal of oestrogen. The major characteristic of osteoporosis is the low bone mass with micro-architectural deteriorated bone tissue. And the main cause is the overactivation of osteoclastogenesis, which is one of the most important therapeutic targets. Inflammation could induce the interaction of RANKL/RANK, which is the promoter of osteoclastogenesis. Triptolide is derived from the traditional Chinese herb lei gong teng, presented multiple biological effects, including anti-cancer, anti-inflammation and immunosuppression. We hypothesized that triptolide could inhibits osteoclastogenesis by suppressing inflammation activation. In this study, we confirmed that triptolide could suppress RANKL-induced osteoclastogenesis in bone marrow mononuclear cells (BMMCs) and RAW264.7 cells and inhibited the osteoclast bone resorption functions. PI3K-AKT-NFATc1 pathway is one of the most important downstream pathways of RANKL-induced osteogenesis. The experiments in vitro indicated that triptolide suppresses the activation of PI3K-AKT-NFATc1 pathway and the target point located at the upstream of AKT because both NFATc1 overexpression and AKT phosphorylation could ameliorate the triptolide suppression effects. The expression of MDM2 was elevated, which demonstrated the MDM-p53-induced cell death might contribute to the osteoclastogenesis suppression. Ovariectomy-induced bone loss and inflammation activation were also found to be ameliorated in the experiments in vivo. In summary, the new effect of anti-cancer drug triptolide was demonstrated to be anti-osteoclastogenesis, and we demonstrated triptolide might be a promising therapy for bone loss caused by tumour. 相似文献
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Kai Xiao Jun Tan Jian Yuan Gang Peng Wenyong Long Jun Su Yao Xiao Qun Xiao Changwu Wu Chaoying Qin Lili Hu Kaili Liu Shunlian Liu Hao Zhou Yichong Ning Xiaofeng Ding Qing Liu 《Journal of cellular and molecular medicine》2020,24(22):13235
Glioblastoma (GBM) is a malignant intracranial tumour with the highest proportion and lethality. It is characterized by invasiveness and heterogeneity. However, the currently available therapies are not curative. As an essential environmental cue that maintains glioma stem cells, hypoxia is considered the cause of tumour resistance to chemotherapy and radiation. Growing evidence shows that immunotherapy focusing on the tumour microenvironment is an effective treatment for GBM; however, the current clinicopathological features cannot predict the response to immunotherapy and provide accurate guidance for immunotherapy. Based on the ESTIMATE algorithm, GBM cases of The Cancer Genome Atlas (TCGA) data set were classified into high‐ and low‐immune/stromal score groups, and a four‐gene tumour environment‐related model was constructed. This model exhibited good efficiency at forecasting short‐ and long‐term prognosis and could also act as an independent prognostic biomarker. Additionally, this model and four of its genes (CLECL5A, SERPING1, CHI3L1 and C1R) were found to be associated with immune cell infiltration, and further study demonstrated that these four genes might drive the hypoxic phenotype of perinecrotic GBM, which affects hypoxia‐induced glioma stemness. Therefore, these might be important candidates for immunotherapy of GBM and deserve further exploration. 相似文献