Canadian Journal of Forest Research最新文献

Aim: To evaluate the detection rate of subclinical carotid atherosclerosis in rheumatoid arthritis (RA) patients with low cardiovascular risk (CVR).

Materials and methods: The study included 182 RA patients with low CVR (mSCORE<1%) and no established cardiovascular diseases and a control group comprising 100 people. Atherosclerotic lesion of the carotid arteries was assessed using Doppler ultrasound of the carotid arteries and was determined by the detection of atherosclerotic plaque (ASP) - the local increase in the thickness of the intima-media complex (IMT) >1.5 mm.

Results: Carotid ASP were observed more frequently in RA patients with low CVR than in the control group (17% versus 8%; p=0.02). The frequency of ASP in RA patients with low CVR did not depend on the disease's stage or activity and ongoing therapy. In RA, the detection of subclinical atherosclerosis was associated with traditional risk factors: carotid ASP were detected 4 times more often in men than in women (48% versus 12%, p<0.01); carotid IMT correlated with age (R=0.46), body mass index (R=0.17), LDL-C level (R=0.20), systolic blood pressure (R=0.17); p<0.05 in all cases. According to a multivariate model, in RA, the risk of developing ASP increased in the presence of dyslipidemia (odds ratio - OR 2.97; 95% confidence interval - CI 1.36-6.49; p=0.006) and arterial hypertension (OR 2.16; 95% CI 1.03-4.54; p=0.04). In RA patients with carotid ASP, sCD40L level was associated with carotid IMT (R=0.32; p=0.04) and cholesterol concentration (R=0.39; p=0.01).

Conclusion: Subclinical atherosclerotic lesions of the carotid arteries were observed in 24% of RA patients with low cardiovascular risk and were detected almost 2 times more often than in the control group. In RA patients with low CVR, the risk of developing carotid ASP increased by 2-3 times with concomitant hypertension and dyslipidemia. The carotid IMT was associated with traditional risk factors - age, gender, lipid levels and blood pressure indicators, in cases of detection of ASP - with an immunoinflammatory marker - sCD40L.

Microbial lysis of dimethylsulfoniopropionate (DMSP) is a key step in marine organic sulfur cycling and has been recently demonstrated to play an important role in mediating interactions between bacteria, algae, and zooplankton. To date, microbes that have been found to lyse DMSP are largely confined to free-living and surface-attached bacteria. In this study, we report for the first time that a symbiont (termed "Rhodobiaceae bacterium HWgs001") in the gill of the marine scallop Argopecten irradians irradians can lyse and metabolize DMSP. Analysis of 16S rRNA gene sequences suggested that HWgs001 accounted for up to 93% of the gill microbiota. Microscopic observations suggested that HWgs001 lived within the gill tissue. Unlike symbionts of other bivalves, HWgs001 belongs to Alphaproteobacteria rather than Gammaproteobacteria, and no genes for carbon fixation were identified in its small genome. Moreover, HWgs001 was found to possess a dddP gene, responsible for the lysis of DMSP to acrylate. The enzymatic activity of dddP was confirmed using the heterologous expression, and in situ transcription of the gene in scallop gill tissues was demonstrated using reverse-transcription PCR. Together, these results revealed a taxonomically and functionally unique symbiont, which represents the first-documented DMSP-metabolizing symbiont likely to play significant roles in coastal marine ecosystems.