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991.
992.

Aim

Recent research has focused attention on the single nucleotide polymorphisms (SNPs) involved in the host response in periodontitis. However, so as to combine the relatively small effects of individual genes the use of multi locus genetic risk (GRS) has been proposed. This study aims to evaluate whether the genetic risk score may predict periodontitis onset and progression.

Materials and methods

Fifty patients were divided into various groups according to periodontal status. Total DNA was isolated from epithelial oral cells by a masked operator and the selected SNPs were analysed. A GRS was calculated using an additive model.

Results

We found a strong association only between TNF rs1800629 and diffused forms of periodontitis. Data show that GRS is able to discriminate diffused forms of periodontitis from localized ones. Finally, a progressive increase of the GRS is evident in advanced periodontitis in comparison with early forms.

Discussion

In recent years, research on genetic polymorphism has had limited success in predicting the susceptibility to periodontal disease. However, our results indicate that the use of the genetic risk score could be promising. Further studies are necessary to include data from multiple genes so as to confirm our result.  相似文献   
993.

Background and Purpose

The cannabinoid receptor-mediated analgesic effects of 2-arachidonoylglycerol (2-AG) are limited by monoacylglycerol lipase (MAGL). 4-nitrophenyl 4-[bis (1,3-benzodioxol-5-yl) (hydroxy) methyl] piperidine-1-carboxylate (JZL184) is a potent inhibitor of MAGL in the mouse, though potency is reportedly reduced in the rat. Here we have assessed the effects of spinal inhibition of MAGL with JZL184 on nociceptive processing in rats.

Experimental Approach

In vivo spinal electrophysiological assays in anaesthetized rats were used to determine the effects of spinal administration of JZL184 on spinal nociceptive processing in the presence and absence of hindpaw inflammation. Contributions of CB1 receptors to these effects was assessed with AM251. Inhibition of 2-oleoylglycerol hydrolytic activity and alterations of 2-AG in the spinal cord after JZL 184 were also assessed.

Key Results

Spinal JZL184 dose-dependently inhibited mechanically evoked responses of wide dynamic range (WDR) neurones in naïve anaesthetized rats, in part via the CB1 receptor. A single spinal administration of JZL184 abolished inflammation-induced expansion of the receptive fields of spinal WDR neurones. However, neither spinal nor systemic JZL184 altered levels of 2-AG, or 2-oleoylglycerol hydrolytic activity in the spinal cord, although JZL184 displayed robust inhibition of MAGL when incubated with spinal cord tissue in vitro.

Conclusions and Implications

JZL184 exerted robust anti-nociceptive effects at the level of the spinal cord in vivo and inhibited rat spinal cord MAGL activity in vitro. The discordance between in vivo and in vitro assays suggests that localized sites of action of JZL184 produce these profound functional inhibitory effects.

Linked Articles

This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.167.issue-8  相似文献   
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Leukocytes are thought to play an important role in the pathogenesis of inflammatory bowel diseases; granulocyte-monocyte adsorptive (GMA) apheresis, an extracorporeal technique aimed at removing activated circulating leukocytes from the blood, may represent a safe and effective therapeutic tool in these patients. The Italian Registry of Therapeutic Apheresis performed an observational, multicentric study involving 24 Gastroenterology Units. In this study, laboratory data and clinical outcomes of 230 patients (148 males, mean age 43.5 years) affected with ulcerative colitis (UC, n = 194) or Crohn's disease (CD, n = 36) who underwent one or more cycles of GMA were analyzed. Each cycle consisted of five GMA treatments. The patients were followed up for a mean of 8.7 (min. 3 to max. 12) months. At 3 months, positive outcome was achieved in 77.7% of UC patients (72.0% remission, 5.7% clinical response) and 61.3% of CD patients (54.8% remission, 6.5% clinical response). The cumulative proportion of positive outcome at 12 months was 87.1% for UC patients (83.7% remission, 3.4% clinical response) and 77.4% for CD patients (74.2% remission, 3.2% clinical response). No single clinical or laboratory parameter among those analyzed (age, sex, disease characteristics, history of smoking, medication history, baseline values of clinical activity index (CAI)/Crohn's disease activity index (CDAI), hemoglobin, white blood cells count, and erythrocyte sedimentation rate) was independently associated with clinical outcome. The procedure was well tolerated with no significant adverse effects registered.  相似文献   
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Because macrophage migration inhibitory factor (MIF) is a key cytokine in pregnancy and has a role in inflammatory response and pathogen defense, the objective of the present study was to investigate the effects of MIF in first- and third-trimester human placental explants infected with Toxoplasma gondii. Explants were treated with recombinant MIF, IL-12, interferon-γ, transforming growth factor-β1, or IL-10, followed by infection with T. gondii RH strain tachyzoites. Supernatants of cultured explants were assessed for MIF production. Explants were processed for morphologic analysis, immunohistochemistry, and real-time PCR analysis. Comparison of infected and stimulated explants versus noninfected control explants demonstrated a significant increase in MIF release in first-trimester but not third-trimester explants. Tissue parasitism was higher in third- than in first-trimester explants. Moreover, T. gondii DNA content was lower in first-trimester explants treated with MIF compared with untreated explants. However, in third-trimester explants, MIF stimulus decreased T. gondii DNA content only at the highest concentration of the cytokine. In addition, high expression of MIF receptor was observed in first-trimester placental explants, whereas MIF receptor expression was low in third-trimester explants. In conclusion, MIF was up-regulated and demonstrated to be important for control of T. gondii infection in first-trimester explants, whereas lack of MIF up-regulation in third-trimester placentas may be involved in higher susceptibility to infection at this gestational age.  相似文献   
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Sepsis is the most common and severe cause of morbidity and mortality among critically ill patients. Multiple organ dysfunction syndrome often complicates sepsis, leading to a worse prognosis that is proportional to the severity and number of damaged organs. Acute kidney injury (AKI) also complicates sepsis, with a linear relationship between the severity of kidney damage and sepsis prognosis. The management of sepsis and septic AKI involves intensive proactive preventive measures, medical and extracorporeal treatment of established sepsis, support of failing organs and rehabilitation of the residual effects left by this devastating syndrome. Unfortunately, although some innovations in the clinical management of sepsis are now available, their beneficial effects on renal function are still uncertain. The aim of this Review is to provide an update on the current state of interventions in sepsis-related AKI. Prevention, pharmacological support and extracorporeal blood purification for septic AKI will be reviewed and discussed.  相似文献   
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Oxidative stress is a metabolic condition arising from imbalance between the production of potentially reactive oxygen species and the scavenging activities. Mitochondria are the main providers but also the main scavengers of cell oxidative stress. The role of mitochondrial dysfunction and oxidative stress in the pathogenesis of neurodegenerative diseases is well documented. Therefore, therapeutic approaches targeting mitochondrial dysfunction and oxidative damage hold great promise in neurodegenerative diseases. Despite this evidence, human experience with antioxidant neuroprotectants has generally been negative with regards to the clinical progress of disease, with unclear results in biochemical assays. Here we review the antioxidant approaches performed so far in neurodegenerative diseases and the future challenges in modern medicine.  相似文献   
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