Confounding and interaction effect of Treponema denticola salivary carriage in chronic periodontitis

Oral Diseases (2010) 16 , 278–285 Aim: To evaluate the salivary carriage of Treponema denticola and its association with demographic variables in the etiopathogenesis of chronic periodontitis. Subjects and methods: Ninety‐seven chronic periodontitis (CP) patients and a control group of 51 healthy subjects (HC) were selected. Periodontal status was assessed by criteria based on probing depth, attachment loss, extent, and severity of periodontal breakdown. A polymerase chain reaction method was used to determine the occurrence of T. denticola in saliva samples. Risk indicators for CP were assessed individually and adjusted for confounding and/or interaction using a logistic regression model. Results: Although univariate analysis revealed a positive association of age ≥30 years, smoking, and salivary carriage of T. denticola with CP, after logistic regression analysis, the association between age ≥30 years/smoking and CP persisted, whereas salivary carriage of T. denticola failed to achieve statistical significance. An interaction effect was significantly detected between these three variables. Conclusion: Although salivary carriage of T. denticola may be a risk indicator for CP, its pathogenicity should not be exclusively endorsed to its detection in saliva, but it might be associated with the synergistic biological interaction of the bacterium with some demographic characteristics of the susceptible host.     

Pharmacogenetic characterization of indacaterol,a novel β2-adrenoceptor agonist

Background and purpose:

Indacaterol is a novel β₂-adrenoceptor agonist in development for the treatment of chronic obstructive pulmonary disease. The aim of this study was to investigate the comparative pharmacology of indacaterol in recombinant cells expressing the common polymorphic variants of the human β₂-adrenoceptor and in human primary airway smooth muscle (ASM) cells.

Experimental approach:

Chinese hamster ovarian-K1 cell lines expressing high and low levels of the common human β₂-adrenoceptor variants were generated [Gly16-Glu27-Val34-Thr164(GEVT), RQVT, GQVT] and also the rare GQVI variant. Human primary ASM cells were isolated from explants of trachealis muscle. Adenosine-3′,5′-cyclic-monophosphate production was used as an outcome measure.

Key results:

In both the low- and high-expression recombinant GEVT ‘wild type’ cell lines indacaterol is a high-efficacy agonist. Salmeterol and formoterol were identified as low- and high-efficacy agonists, respectively, and showed similar potencies to indacaterol irrespective of the β₂-adrenoceptor genotype. The I164 variant cell line was associated with a reduced capacity to generate adenosine-3′,5′-cyclic-monophosphate in response to β₂-adrenoceptor agonist. In the human primary ASM cells indacaterol gave a maximal response intermediate between that of salmeterol and formoterol.

Conclusions and implications:

These data demonstrate that indacaterol is a high-efficacy agonist in recombinant cell systems but acts with lower efficacy in human primary ASM cells. No marked genotype-dependent effects were observed for common variants; however, changes in I164 receptor activity were identified, which were dependent on the level of expression of β₂-adrenoceptors.     

Therapeutic action and underlying mechanisms of a combination of two pentacyclic triterpenes, α- and β-amyrin,in a mouse model of colitis

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg⁻¹, i.p.) or dexamethasone (1 mg·kg⁻¹, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.     

Pathological features and inhaled corticosteroid response of eosinophilic and non-eosinophilic asthma

Background

Non‐eosinophilic asthma is a potentially important clinicopathological phenotype since there is evidence that it responds poorly to inhaled corticosteroid therapy. However, little is known about the underlying airway immunopathology and there are no data from placebo‐controlled studies examining the effect of inhaled corticosteroids.

Methods

Airway immunopathology was investigated using induced sputum, bronchial biopsies, bronchial wash and bronchoalveolar lavage in 12 patients with symptomatic eosinophilic asthma, 11 patients with non‐eosinophilic asthma and 10 healthy controls. The patients with non‐eosinophilic asthma and 6 different patients with eosinophilic asthma entered a randomised, double‐blind, placebo‐controlled crossover study in which the effects of inhaled mometasone 400 μg once daily for 8 weeks on airway responsiveness and asthma quality of life were investigated.

Results

Patients with non‐eosinophilic asthma had absence of eosinophils in the mucosa (median 4.4 cells/mm² vs 23 cells/mm² in eosinophilic asthma and 0 cells/mm² in normal controls; p = 0.03) and normal subepithelial layer thickness (5.8 μm vs 10.3 μm in eosinophilic asthma and 5.1 μm in controls, p = 0.002). Non‐eosinophilic and eosinophilic asthma groups had increased mast cell numbers in the airway smooth muscle compared with normal controls (9 vs 8 vs 0 cells/mm², p = 0.016). Compared with placebo, 8 weeks of treatment with inhaled mometasone led to less improvement in methacholine PC₂₀ (0.5 vs 5.5 doubling concentrations, 95% CI of difference 1.1 to 9.1; p = 0.018) and asthma quality of life (0.2 vs 1.0 points, 95% CI of difference 0.27 to 1.43; p = 0.008).

Conclusions

Non‐eosinophilic asthma represents a pathologically distinct disease phenotype which is characterised by the absence of airway eosinophilia, normal subepithelial layer thickness and a poor short‐term response to treatment with inhaled corticosteroids.Clinicians have long regarded asthma as a heterogeneous disease,^1,2 although detailed clinicopathological studies have tended to emphasise the similarities in the underlying airway pathology and disordered function between patients.^3,4 The development of safe non‐invasive induced sputum techniques has provided the opportunity to study airway inflammation in a diverse range of patients. Using this technique, we and a number of other groups have identified a subset of adults who have clear physiological evidence of asthma but no induced sputum evidence of eosinophilic airway inflammation.^5,6,7 This asthma phenotype is potentially clinically important since several uncontrolled studies have suggested that it is associated with a poor short‐term and longer‐term response to inhaled corticosteroid.^5,8,9Non‐eosinophilic asthma is present in 53% of patients presenting to an adult respiratory clinic with symptomatic asthma.⁹ Other investigators have reported the absence of a sputum eosinophilia in up to 50% of patients with refractory asthma,⁹ patients studied during an asthma exacerbation¹⁰ and patients taking high doses of inhaled corticosteroids.⁶ In a recent longitudinal study of patients with severe asthma, the absence of sputum eosinophils has been reported to be a stable feature in a number of patients observed over 12 months;¹¹ another study showed that it was present in untreated symptomatic patients as well as those receiving inhaled corticosteroid therapy.⁹ These observations suggest that, in some patients at least, non‐eosinophilic asthma is a stable phenotype that is not solely explained by the effects of corticosteroid therapy.Several studies have noted that an airway neutrophilia is often present in patients with non‐eosinophilic asthma, and Wenzel et al⁷ reported a predominantly neutrophilic airway inflammatory response with an absence of eosinophils and normal basement membrane thickness in a subgroup of patients with refractory asthma from whom bronchial biopsy specimens were taken. These findings support the concept that non‐eosinophilic asthma is a pathologically distinct entity, although the extent to which these findings reflect the effects of treatment remains unclear.The aim of this study was to compare the immunopathology of eosinophilic and non‐eosinophilic asthma with normal controls in patients with symptomatic asthma who were not treated with inhaled corticosteroids. We also set out to compare the response to 8 weeks of treatment with the inhaled corticosteroid mometasone in a prospective randomised, double‐blind, placebo‐controlled crossover trial in patients with non‐eosinophilic asthma and in a subgroup with eosinophilic asthma.     

Monoclonal antibody F1 binds to the kringle domain of factor XII and induces enhanced susceptibility for cleavage by kallikrein

In a previous study we have shown that monoclonal antibody F1 (MoAb F1), directed against an epitope on the heavy chain of factor XII distinct from the binding site for anionic surfaces, is able to activate factor XII in plasma (Nuijens JH, et al: J Biol Chem 264; 12941, 1989). Here, we studied in detail the mechanism underlying the activation of factor XII by MoAb F1 using purified proteins. Formation of factor XIIa was assessed by measuring its amidolytic activity towards the chromogenic substrate H-D-Pro-Phe-Arg-pNA (S-2302) in the presence of soybean trypsin inhibitor and by assessing cleavage on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Upon incubation with MoAb F1 alone, factor XII was auto-activated in a time-dependent fashion, activation being maximal after 30 hours. Factor XII incubated in the absence of MoAb F1 was hardly activated by kallikrein, whereas in the presence of MoAb F1, but not in that of a control MoAb, the rate of factor XII activation by kallikrein was promoted at least 60-fold. Maximal activation of factor XII with kallikrein in the presence of MoAb F1 was reached within 1 hour. This effect of kallikrein on the cleavage of factor XII bound to MoAb F1 was specific because the fibrinolytic enzymes plasmin, urokinase, and tissue-type plasminogen activator could not substitute for kallikrein. Also, trypsin could easily activate factor XII, but in contrast to kallikrein, this activation was independent of MoAb F1. SDS-PAGE analysis showed that the appearance of amidolytic activity correlated well with cleavage of factor XII. MoAb F1-induced activation of factor XII in this purified system was not dependent on the presence of high- molecular-weight kininogen (HK), in contrast to the activation of the contact system in plasma by MoAb F1. Experiments with deletion mutants revealed that the epitopic region for MoAb F1 on factor XII is located on the kringle domain. Thus, this study shows that binding of ligands to the kringle domain, which does not contribute to the proposed binding site for negatively charged surfaces, may induce activation of factor XII. Therefore, these findings point to the existence of multiple mechanisms of activation of factor XII.     

开道散合扶正和胃合剂治疗上消化道癌性狭窄疗效观察

目的：观察开道散合扶正和胃合剂治疗上消化道癌性狭窄的临床疗效。方法：对40例患者采用口服开道散、扶正和胃合剂联合胃镜下癌灶内注射5-氟脲嘧啶注射液及鸦胆子乳剂方法治疗上消化道癌性狭窄。结果：治疗后无瘤灶消失病例,34例患者肿瘤缩小达50％以上,完全缓解0例,部分缓解34例,稳定4例,进展2例,有效率为85．0％。治疗后患者吞咽困难有了较明显的改善,显效7例,有效31例,无效2例,总有效率95．0％。治疗后所有患者的卡氏评分均有所升高,与治疗前比较,差异有显著性意义（P〈0．05）,提示治疗后患者的生活质量有所改善。结论：开道散合扶正和胃合剂治疗上消化道癌性狭窄疗效满意,能使实体瘤缩小、吞咽困难改善、生活质量提高。     

Ewing’s肉瘤细胞X-射线照射后TNF-α和TGF-β mRNA表达的研究

 目的　研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法　应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果　RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论　Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82...