Interleukin-6 gene promoter methylation in rheumatoid arthritis and chronic periodontitis

Background: Methylation status of the cytokine genes may play a role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA) and chronic periodontitis (CP). This study was undertaken to evaluate whether the DNA methylation profile of the interleukin‐6 (IL‐6) gene promoter was unique to individuals with RA and CP. Methods: The study participants consisted of 30 patients with RA, 30 patients with CP, and 30 age‐, sex‐, and smoking status–balanced healthy controls. Genomic DNA isolated from peripheral blood was modified by sodium bisulfite and analyzed for DNA methylation levels of IL‐6 gene with direct sequencing. Levels of IL‐6 were determined by an enzyme‐linked immunosorbent assay. Results: The region of IL‐6 gene promoter from ?1200 to +27 bp was shown to contain 19 CpG motifs. The methylation levels of the CpG motif at ?74 bp were significantly lower in patients with RA and CP than those in controls (P = 0.0001). Both levels of serum IL‐6 and IL‐6 production by mononuclear cells were significantly different between individuals with and without the methylation at ?74 bp (P = 0.03). The +19 bp motif exhibited differential levels of the methylation among the groups, which was not associated with serum levels of IL‐6. The other 17 CpG motifs exhibited comparable levels of the methylation between the groups. Conclusion: These results suggest that hypomethylated status of a single CpG in the IL‐6 promoter region may lead to increased levels of serum IL‐6, implicating a role in the pathogenesis of RA and CP.     

Distribution of polycyclic aromatic hydrocarbons concentrations simultaneously obtained in gas,rainwater and particles

This study reported the distribution of polycyclic aromatic hydrocarbons (PAHs) concentrations simultaneously obtained in gas/rain/particle in rain event from 2010 to 2012 in Osaka, Japan. A sampling method for rain and the materials of a rain collector were also surveyed. Benzene and a glass bottle were used to prevent the decrease of PAHs in rainwater. The average concentration of Σ9PAHs in rainwater ranged between 17.49 and 646.52 ng dm^?3. The mean ratio of these Σ9PAHs in gas versus particles was 77.9 and 68.3 % during rain and no rain, respectively. During rain, the PAHs in particles were scavenged by rain and were incorporated via washout by collision with each other. Therefore, the ratio of PAHs in rainwater was similar to that in particles. The low molecular weight LMW-PAHs from gas were recognized as being dissolved in rain but did not affect the ratio of PAHs in rain. Four rings PAH were dominant in gas/rain/particles. The seasonal variation of Σ9PAHs in rainwater was reported and discussed, and the PAHs levels during the winter and spring were higher compared with that of summer and autumn. Furthermore, the sampling method of PAHs in snow is also developed.     

Identification of active sites in amidase: Evolutionary relationship between amide bond- and peptide bond-cleaving enzymes

Mainly based on various inhibitor studies previously performed, amidases came to be regarded as sulfhydryl enzymes. Not completely satisfied with this generally accepted interpretation, we performed a series of site-directed mutagenesis studies on one particular amidase of Rhodococcus rhodochrous J1 that was involved in its nitrile metabolism. For these experiments, the recombinant amidase was produced as the inclusion body in Escherichia coli to greatly facilitate its recovery and subsequent purification. With regard to the presumptive active site residue Cys203, a Cys203 → Ala mutant enzyme still retained 11.5% of the original specific activity. In sharp contrast, substitutions in certain other positions in the neighborhood of Cys203 had a far more dramatic effect on the amidase. Glutamic acid substitution of Asp191 reduced the specific activity of the mutant enzyme to 1.33% of the wild-type activity. Furthermore, Asp191 → Asn substitution as well as Ser195 → Ala substitution completely abolished the specific activity. It would thus appear that, among various conserved residues residing within the so-called signature sequence common to all amidases, the real active site residues are Asp191 and Ser195 rather than Cys203. Inasmuch as an amide bond (CO-NH₂) in the amide substrate is not too far structurally removed from a peptide bond (CO-NH-), the signature sequences of various amidases were compared with the active site sequences of various types of proteases. It was found that aspartic acid and serine residues corresponding to Asp191 and Ser195 of the Rhodococcus amidase are present within the active site sequences of aspartic proteinases, thus suggesting the evolutionary relationship between the two.     

Clinical improvements in higher brain function and rapid functional recovery in a case of cerebellar hemorrhage treated by neurocognitive rehabilitation

Cerebellar stroke rarely causes disorders of higher brain function such as cognitive deficits and emotional dysfunction; hence, the prognosis of these patients is uncertain. We report the case of a 34-year-old patient with cerebellar hemorrhage due to arteriovenous malformation causing higher brain dysfunction who was able to return to full-time employment after neurocognitive rehabilitation. Cerebellar stroke caused by nonatherosclerotic diseases or diaschisis may lead to cognitive deficits but these symptoms can be reversed by appropriate therapy. It is important to assess higher brain function in cerebellar stroke patients and to tailor neurocognitive rehabilitation programs appropriately to promote functional recovery.     

Assessment of Interleukin‐6 Receptor Inhibition Therapy on Periodontal Condition in Patients With Rheumatoid Arthritis and Chronic Periodontitis

Background: Overproduction of interleukin (IL)‐6 may play a pathologic role in rheumatoid arthritis (RA) and chronic periodontitis (CP). The present study assesses IL‐6 receptor (IL‐6R) inhibition therapy on the periodontal condition of patients with RA and CP. Methods: The study participants were 28 patients with RA and CP during treatment with IL‐6R inhibitor, and 27 patients with RA and CP during treatment without IL‐6R inhibitor. Periodontal and rheumatologic parameters and serum levels of cytokine and inflammatory markers and immunoglobulin G against periodontopathic bacteria were examined after medication with IL‐6R inhibitor for 20.3 months on average (T1) and again 8 weeks later (T2). Results: No differences were observed between the groups in any parameter values at T1, except for serum IL‐6 levels. The anti–IL‐6R group showed a significantly greater decrease in gingival index, bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and serum levels of IL‐6 and matrix metalloproteinase (MMP)‐3 from T1 to T2 than the control group (P <0.05). A significant correlation was found between changes in serum anticyclic citrullinated peptide levels and those in PD and CAL in the anti–IL‐6R group (P <0.05), whereas both groups exhibited a significant association between changes in serum MMP‐3 levels and those in BOP (P <0.05). Conclusion: Changes in periodontal and serum parameter values were different between the patients with RA and CP during treatment with and without IL‐6R inhibitor.