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141.
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目的 探讨双氯芬酸钠对脂多糖(LPS)诱导的人牙周膜成纤维细胞(HPDLFs)白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)表达的影响。方法 本研究于2013年3—5月在山西医科大学口腔实验室进行。将复苏培养冻存的HPDLFs进行形态学鉴别后,用10 μg/mL的LPS进行诱导,分别以0.1、1、10、50、100 mg/L的双氯芬酸钠进行干预,酶联免疫吸附试验法(ELISA法)检测HPDLFs表达IL-1β和TNF-α水平的变化。结果 对同一质量浓度LPS诱导的HPDLFs而言,双氯芬酸钠能下调HPDLFs表达IL-1β和TNF-α的水平,并且随着双氯芬酸钠质量浓度的增加,IL-1β和TNF-α的表达量呈逐渐减弱的趋势(P<0.05)。结论 双氯芬酸钠可能对于LPS诱导的HPDLFs IL-1β和TNF-α的表达有重要的抑制作用,这为牙周病的临床治疗提供了新的思路。  相似文献   
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Abstract

Context: Acute kidney injury (AKI) is considered a major public health concern in today’s world. Sepsis‐induced AKI is large as a result of exposure to lipopolysaccharide (LPS) that is the major outer membrane component of Gram‐negative bacteria. Sesamin is the main lignan of sesame seeds with multiple protective effects.

Objective: In this research, we tried to demonstrate the protective effect of sesamin pretreatment in LPS-induced mouse model of AKI.

Methods: LPS was injected at a single dose of 10?mg/kg (i.p.) and sesamin was given p.o. at doses of 25, 50, or 100?mg/kg, one hour prior to LPS.

Results: Treatment of LPS-challenged mice with sesamin reduced serum level of creatinine and blood urea nitrogen (BUN) and returned back renal oxidative stress-related parameters including glutathione (GSH), malondialdehyde (MDA), and activity of catalase and superoxide dismutase (SOD). Moreover, sesamin alleviated inappropriate changes of renal nuclear factor-kappaB (NF-κB), toll-like receptor 4 (TLR4), cyclooxygenase-2 (COX2), tumor necrosis factor α (TNFα), interleukin-6, DNA fragmentation (an apoptotic index), and nuclear factor (erythroid-derived 2)-like 2 (Nrf2). In addition, sesamin diminished magnitude of kidney tissue damage due to LPS.

Conclusion: In summary, sesamin could dose-dependently abrogate LPS-induced AKI via attenuation of renal oxidative stress, inflammation, and apoptosis.  相似文献   
144.
Populations in high infectious exposure countries are at low risk of some immune-mediated diseases such as Crohn's disease and allergy. This low risk is maintained upon immigration to an industrialized country, but the offspring of such immigrants have a higher immune-mediated disease risk than the indigenous population. We hypothesize that early life exposures in a developing country shape the maternal immune system, which could have implications for the offspring born in a developed country with a low infectious load. The aim of this study was to investigate if exposures in childhood (indicated by country of origin) and subsequent exposures influence immunologic characteristics relevant to stimulation of offspring. Breast milk components among 64 mothers resident in Sweden, 32 of whom immigrated from a developing country, were examined using the ELISA and Cytometric Bead Array methods. Immigrants from a developing country had statistically significantly higher levels of breast milk interleukin-6 (IL-6), IL-8 and transforming growth factor-β1. A larger number of previous pregnancies were associated with down-regulation of several substances, statistically significant for soluble CD14 and IL-8. The results suggest that maternal country of birth may influence adult immune characteristics, potentially relevant to disease risk in offspring. Such a mechanism may explain the higher immune-mediated disease risk among children of migrants from a developing to developed country. Older siblings may influence disease risk through the action of previous pregnancies on maternal immune characteristics.  相似文献   
145.
Therapeutic vaccines present an attractive alternative to conventional treatments for cancer. However, tumors have evolved various immune evasion mechanisms to modulate innate, adaptive, and regulatory immunity for survival. Therefore, successful vaccine formulations may require a non-toxic immunomodulator or adjuvant that not only induces/stimulates innate and adaptive tumor-specific immune responses, but also overcomes immune evasion mechanisms. Given the paramount role costimulation plays in modulating innate, adaptive, and regulatory immune responses, costimulatory ligands may serve as effective immunomodulating components of therapeutic cancer vaccines. Our laboratory has developed a novel technology designated as ProtEx that allows for the generation of recombinant costimulatory ligands with potent immunomodulatory activities and the display of these molecules on the cell surface in a rapid and efficient manner as a practical and safe alternative to gene therapy for immunomodulation. Importantly, the costimulatory ligands not only function when displayed on tumor cells, but also as soluble proteins that can be used as immunomodulatory components of conventional vaccine formulations containing tumor-associated antigens (TAAs). We herein discuss the application of the ProtEx technology to the development of effective cell-based as well as cell-free conventional therapeutic cancer vaccines.  相似文献   
146.
Multiple sclerosis is a very disabling inflammatory demyelinating disease of the brain of unknown etiology. Current therapies can reduce new lesion development and partially prevent clinical disease activity, but none can halt the progression, or cure the disease. We will review current therapeutic strategies, which are mostly discussed in literature in terms of their effective inhibition of T cells. However, we argue that many of these treatments also influence the myeloid compartment. Interestingly, recent evidence indicates that myelin phagocytosis by infiltrated macrophages and activated microglia is not just a hallmark of multiple sclerosis, but also a key determinant of lesion development and disease progression. We reason that severe side effects and/or insufficient effectiveness of current treatments necessitates the search for novel therapeutic targets, and postulate that these should aim at manipulation of the activation and phagocytic capacity of macrophages and microglia. We will discuss three candidate targets with high potential, namely the complement receptor 3, CD47–SIRPα interaction as well as CD200–CD200R interaction. Blocking the actions of complement receptor 3 could inhibit myelin phagocytosis, as well as migration of myeloid cells into the brain. CD47 and CD200 are known to inhibit macrophage/microglia activation through binding to their receptors SIRPα and CD200R, expressed on phagocytes. Triggering these receptors may thus dampen the inflammatory response. Our recent findings indicate that the CD200–CD200R interaction is the most specific and hence probably best-suited target to suppress excessive macrophage and microglia activation, and restore immune suppression in the brain of patients with multiple sclerosis.  相似文献   
147.
Development of the meningococcal serogroup C conjugate vaccine and its national implementation in the UK has been a major breakthrough in the prevention of meningococcal disease. New technologies are increasing the likelihood that research towards a vaccine against group B meningococcus will be successful. This review covers the recent development of vaccines against meningococcal disease and examines future vaccine candidates. The development of meningococcal polysaccharide vaccines was based on the virulence of the bacterial capsule components. The immunogenicity of these vaccines has been improved by covalent linkage to proteins in the new meningococcal C conjugate vaccines. However, the most promising developments for serogroup B disease have stemmed from other virulence determinants such as outer membrane proteins (OMPs) and lipopolysaccharides (LPS). New genome sequencing technology promises a way forward to developing a broadly cross-protective vaccine for this important pathogen.  相似文献   
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Platelets have been extensively studied as hemostatic regulators, stopping uncontrolled flow of blood from an injured vessel and allowing for repair. However, multiple studies have shown that platelets can interact with bacterial proteins, particularly seen during sepsis and inflammation. Immune cells recognize pathogens through Toll-like Receptors (TLRs). These same receptors allow platelets to recognize bacterial proteins and regulate platelet immunity and function. This review examines the TLRs expressed on platelets and megakaryocytes and how these receptors affect the function of these cells. Through TLRs, platelets go beyond hemostatic regulation and play a pivotal role in inflammation and infection.  相似文献   
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