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91.
Recent clinical success has underscored the potential for immunotherapy based on the adoptive cell transfer (ACT) of engineered T lymphocytes to mediate dramatic, potent, and durable clinical responses. This success has led to the broader evaluation of engineered T-lymphocyte-based adoptive cell therapy to treat a broad range of malignancies. In this review, we summarize concepts, successes, and challenges for the broader development of this promising field, focusing principally on lessons gleaned from immunological principles and clinical thought. We present ACT in the context of integrating T-cell and tumor biology and the broader systemic immune response.  相似文献   
92.
The aim of this study was to investigate the association between the magnitude of anti-nociceptive effects induced by heterotopic noxious counter-stimulation (HNCS) and the basal μ-opioid receptor availability in the amygdala. In 8 healthy volunteers (4 females and 4 males), transcutaneous electrical stimulation was applied to the right sural nerve to produce the nociceptive flexion reflex (RIII-reflex), moderate pain, and scalp somatosensory evoked potentials (SEPs). Immersion of the left hand in cold water for 20 min was used as HNCS. In a separate session, basal μ-opioid receptor availability was measured using positron emission tomography with the radiotracer [11C]carfentanil. HNCS produced a reduction of the P260 amplitude (p < 0.05), a late component of SEP that reflects activity in the anterior cingulate cortex. This reduction was associated with higher basal μ-opioid receptor availability in the amygdala on the right (R2 = 0.55, p = 0.03) with a similar trend on the left (R2 = 0.24, p = 0.22). Besides, HNCS did not induce significant changes in pain and RIII-reflex amplitude (p > 0.05). These results suggest that activation of μ-opioid receptors in the amygdala may contribute to the anti-nociceptive effects of HNCS. The lack of RIII-reflex modulation further suggests that μ-opioid receptor activation in the amygdala contributes to decrease pain-related brain activity through a cerebral mechanism independent of descending modulation.  相似文献   
93.
心肌梗死后的局部炎症反应有加重心肌组织损伤,从而导致心脏重构和心功能不全的不利作用,同时也有清除心肌梗死组织内死亡细胞、基质碎片并促进组织修复的有益作用。近期研究表明,骨髓间充质细胞移植可有效抑制炎症反应对心肌组织损伤和诱导心脏修复的双重效应。本文就急性心肌梗死后心肌组织炎症反应的双重效应与骨髓间充质细胞移植对其产生双重调节作用的研究现状与进展作一综述。  相似文献   
94.
The gut microbiota is a crucial modulator of health effects elicited by food components, with SCFA (short chain fatty acids), especially butyrate, acting as important mediators thereof. We therefore developed a nutritional synbiotic composition targeted at shifting microbiome composition and activity towards butyrate production. An intestinal screening model was applied to identify probiotic Bacillus strains plus various amino acids and peptides with suitable effects on microbial butyrate producers and levels. A pilot study was performed to test if the synbiotic formulation could improve fecal butyrate levels in healthy humans. A combination of Bacillus subtilis DSM (Number of German Collection of Microorganisms and Cell Cultures) 32315 plus L-alanyl-L-glutamine resulted in distinctly increased levels of butyrate and butyrate-producing taxa (Clostridium group XIVa, e.g., Faecalibacterium prausnitzii), both in vitro and in humans. Moreover, circulating lipid parameters (LDL-, and total cholesterol and LDL/HDL cholesterol ratio) were significantly decreased and further metabolic effects such as glucose-modulation were observed. Fasting levels of PYY (Peptide YY) and GLP-1 (Glucagon-like Peptide 1) were significantly reduced. In conclusion, our study indicates that this synbiotic composition may provide an effective and safe tool for stimulation of intestinal butyrate production with effects on e.g., lipid and glucose homeostasis. Further investigations in larger cohorts are warranted to confirm and expand these findings.  相似文献   
95.
Diffuse noxious inhibitory controls (DNIC) are a mechanism of endogenous descending pain modulation and are deficient in a large proportion of chronic pain patients. However, the pathways involved remain only partially determined with several cortical and brainstem structures implicated. This study examined the role of the dorsal reticular nucleus (DRt) and infralimbic (ILC) region of the medial prefrontal cortex in DNIC. In vivo electrophysiology was performed to record from dorsal horn lamina V/VI wide dynamic range neurones with left hind paw receptive fields in anaesthetised sham‐operated and L5/L6 spinal nerve‐ligated (SNL) rats. Evoked neuronal responses were quantified in the presence and absence of a conditioning stimulus (left ear clamp). In sham rats, DNIC were reproducibly recruited by a heterotopically applied conditioning stimulus, an effect that was absent in neuropathic rats. Intra‐DRt naloxone had no effect on spinal neuronal responses to dynamic brush, punctate mechanical, evaporative cooling and heat stimuli in sham and SNL rats. In addition, intra‐DRt naloxone blocked DNIC in sham rats, but had no effect in SNL rats. Intra‐ILC lidocaine had no effect on spinal neuronal responses to dynamic brush, punctate mechanical, evaporative cooling and heat stimuli in sham and SNL rats. However, differential effects were observed in relation to the expression of DNIC; intra‐ILC lidocaine blocked activation of DNIC in sham rats but restored DNIC in SNL rats. These data suggest that the ILC is not directly involved in mediating DNIC but can modulate its activation and that DRt involvement in DNIC requires opioidergic signalling.  相似文献   
96.
97.
目的 研究乙酰胆碱(ACh)、阿托品、毛果芸香碱与正常大鼠蓝斑核(LC)在痛觉调制中的作用及其相互关系.方法 采用电生理学与侧脑室给药的方法,以电脉冲刺激坐骨神经作为伤害性刺激,用玻璃微电极引导LC中痛反应神经元的电变化.观察ACh、阿托品、毛果芸香碱对LC中神经元形态学改变的影响.结果 ACh可使LC内神经元形态发生改变,即神经元体积变大、外形不规则,细胞核轻度水肿等.M受体拮抗剂阿托品能阻断上述作用,使神经元结构基本恢复正常.M受体激动剂毛果芸香碱能产生与ACh相似的效应.结论 外源性ACh不仅能加强大鼠LC中痛反应神经元的电活动,而且使神经元的形态也发生了相应的改变,表现为易化疼痛效应.揭示,ACh的易化疼痛作用主要是通过M受体介导而实现的,LC内神经元形态的改变进一步证实ACh和LC在痛觉调制中起重要作用.  相似文献   
98.
In an ongoing project to evaluate natural compounds isolated from plants from the Brazilian biodiversity as modulators of antibiotic resistance, kaempferol‐3‐Oβ‐d‐(6″‐E‐p‐coumaroyl) glucopyranoside (tiliroside), isolated from Herissantia tiubae (Malvaceae) was investigated using the strain SA‐1199B of Staphylococcus aureus, which overexpresses the norA gene encoding the NorA efflux protein which extrudes hydrophilic fluorquinolones and some biocides, such as benzalkonium chloride, cetrimide, acriflavine and ethidium bromide. The minimum inhibitory concentrations (MICs) of the antibiotics and biocides were determined by the microdilution assay in the absence and in the presence of sub‐inhibitory concentration of tiliroside. Although tiliroside did not display relevant antibacterial activity (MIC = 256 µg/mL), it modulated the activity of antibiotics, i.e. in combination with antibiotics a reduction in the MIC was observed for norfloxacin (16‐fold), ciprofloxacin (16‐fold), lomefloxacin (four‐fold) and ofloxacin (two‐fold), and an impressive reduction in the MICs for the biocides (up to 128‐fold). The results presented here represent the first report of a kaempferol glycoside as a putative efflux pump inhibitor in bacteria. The present finding indicates that H. tiubae (and broadly Malvaceae) could serve as a source of plant‐derived natural products that modulate bacterial resistance, i.e. a source of potential adjuvants of antibiotics. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
99.
The classic pathway (CP) of complement is believed to significantly contribute to alloantibody‐mediated transplant injury, and targeted complement inhibition is currently considered to be a promising approach for preventing rejection. Here, we investigated the mode of action and efficacy of the humanized anti‐C1s monoclonal antibody TNT009 and its parental mouse variant, TNT003, in preclinical in vitro models of HLA antibody–triggered CP activation. In flow cytometric assays, we measured the attachment of C1 subcomponents and C4/C3 split products (C4b/d, C3b/d) to HLA antigen–coated flow beads or HLA‐mismatched aortic endothelial cells and splenic lymphocytes. Anti‐C1s antibodies profoundly inhibited C3 activation at concentrations >20 μg/mL, in both solid phase and cellular assays. While C4 activation was also prevented, this was not the case for C1 subcomponent attachment. Analysis of serum samples obtained from 68 sensitized transplant candidates revealed that the potency of inhibition was related to the extent of baseline CP activation. This study demonstrates that anti‐C1s antibodies TNT009 and TNT003 are highly effective in blocking HLA antibody–triggered complement activation downstream of C1. Our results provide the foundation for clinical studies designed to investigate the potential of TNT009 in the treatment or prevention of complement‐mediated tissue injury in sensitized transplant recipients.  相似文献   
100.
Despite the abundance of information on cutaneous malignancies associated with solid organ transplantation in the transplant literature, there is limited information regarding nonmalignant skin changes after transplantation. There are numerous skin toxicities secondary to immunosuppressive and other transplant‐related medications that can vary in presentation, severity, and prognosis. To limit associated morbidity and mortality, solid organ transplant recipient care providers should effectively identify and manage cutaneous manifestations secondary to drug toxicity. Toxicities from the following transplant‐related medications will be discussed: antithymocyte globulins, systemic steroids, cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, mammalian target of rapamycin inhibitors sirolimus and everolimus, basiliximab and daclizumab, belatacept, and voriconazole.  相似文献   
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