Multilocus sequence typing (MLST) and whole-genome MLST of Campylobacter jejuni isolates from human infections in three districts during a seasonal peak in Finland.

A total of 95 human Campylobacter jejuni isolates acquired from domestic infections and collected from three districts in Finland during the seasonal peak (June to September) in 2012 were analyzed by PCR-based multilocus sequence typing (MLST) and by whole-genome sequencing (WGS). Four predominant sequence types (STs) were detected among the isolates: ST-45 (21%) and ST-230 (14%, ST-45 clonal complex [CC]), ST-267 (21%, ST-283 CC), and ST-677 (19%, ST-677 CC). In districts 1 and 3, most of the infections occurred from early July to the middle of August, with a peak at weeks 29 to 31, but in district 2, the infections were dispersed more evenly throughout 3 months (June to August). WGS data were used for further whole-genome MLST (wgMLST) analyses of the isolates representing the four common STs. Shared loci of the isolates within each ST were analyzed as distance matrices of allelic profiles by the neighbor-net algorithm. The highest allelic variations (>400 different alleles) were detected between different clusters of ST-45 isolates (1,121 shared loci), while ST-230 (1,264 shared loci), ST-677 (1,169 shared loci), and ST-267 isolates (1,217 shared loci) were less diverse with the clusters differing by <40 alleles. Closely related isolates showing no allelic variation (subclusters) were detected among all four major STs. In some cases, they originated from different districts, suggesting that isolates can be epidemiologically connected and may have the same infection source despite being originally identified as sporadic infections.

A cross-sectional study of vitamin D levels in a large cohort of patients with rheumatic diseases.

The objective of this study is to examine 25-hydroxyvitamin D [25(OH)D] (D-25) levels and associations with patient- and disease-related factors in rheumatic diseases. This is a register-based study of D-25 levels in adult patients seen at the Central Finland Hospital rheumatology clinic (January 2011-April 2015). Demographic, clinical, laboratory, and patient-reported outcomes (PROs) were collected as part of the normal infrastructure of the outpatient clinic and examined for their association with D-25 level. Statistical analysis included descriptive statistics and univariable and multivariable regression analyses adjusting for age and gender. D-25 was measured in 3203 patients (age range 15-91 years, mean 54; 68% female) with diagnoses including RA (n = 1386), unspecified arthralgia/myalgia (n = 413), and connective tissues diseases (n = 213). The overall D-25 mean (SD) level was 78 (31) and median (IQR) 75 (55, 97). At baseline, 17.8% had D-25 deficiency, and only 1.6% severe deficiency  (< 25 nmol/l); 34%/49% had sufficient/optimal D-25 levels. Higher D-25 levels were associated with older age, lower BMI, and regular exercise (all p < 0.001) among other factors. In multivariable analyses, younger age, non-white background, higher BMI, smoking, less frequent exercise (p < 0.001), and first visit to the clinic (p = 0.033) remained significantly associated with D-25 deficiency. Among those with sub-optimal D-25 levels, 64% had improved to sufficient/optimal levels after a median (IQR) of 13 (7.8, 22) months. The proportion of patients with D-25 deficiency in this study was generally low. Older patients had considerably higher D-25 levels compared to younger patients. Lower physical exercise and higher BMI were associated with higher risk of deficiency. The study supports the benefit of strategies to help minimize the risk of D-25 deficiency.

Antibacterial effects of human group IIA and group XIIA phospholipase A2 against Helicobacter pylori in vitro.

Group IIA phospholipase A2 (PLA2-IIA) is an enzyme which has important roles in inflammation and infection. Recently, a novel human secretory PLA2 called group XIIA PLA2 (PLA2-XIIA) has been identified. Both PLA2-IIA and PLA2-XIIA are bactericidal against Gram-positive bacteria like many other secretory PLA2s. However, PLA2-XIIA is the only known PLA2 displaying significant bactericidal activity against the Gram-negative bacterium Escherichia coli. We examined the antibacterial properties of recombinant human PLA2-IIA and PLA2-XIIA against Helicobacter pylori, a Gram-negative bacterium, in vitro. PLA2-IIA was not bactericidal against H. pylori, whereas PLA2-XIIA effectively killed H. pylori at a concentration of 50 microg/ml but was not bactericidal at concentrations of 0.5 microg/ml and 5 microg/ml.

Tracing isolates from domestic human Campylobacter jejuni infections to chicken slaughter batches and swimming water using whole-genome multilocus sequence typing.

Campylobacter jejuni is the leading cause of bacterial gastroenteritis and chicken is considered a major reservoir and source of human campylobacteriosis. In this study, we investigated temporally related Finnish human (n=95), chicken (n=83) and swimming water (n=20) C. jejuni isolates collected during the seasonal peak in 2012 using multilocus sequence typing (MLST) and whole-genome MLST (wgMLST). Our objective was to trace domestic human C. jejuni infections to C. jejuni isolates from chicken slaughter batches and swimming water. At MLST level, 79% of the sequence types (STs) of the human isolates overlapped with chicken STs suggesting chicken as an important reservoir. Four STs, the ST-45, ST-230, ST-267 and ST-677, covered 75% of the human and 64% of the chicken isolates. In addition, 50% of the swimming water isolates comprised ST-45, ST-230 and ST-677. Further wgMLST analysis of the isolates within STs, accounting their temporal relationship, revealed that 22 of the human isolates (24%) were traceable back to C. jejuni positive chicken slaughter batches. None of the human isolates were traced back to swimming water, which was rather sporadically sampled. The highly discriminatory wgMLST, together with the patient background information and temporal relationship data with possible sources, offers a new, accurate approach to trace back the origin of domestic campylobacteriosis. Our results suggest that potentially a substantial proportion of campylobacteriosis cases during the seasonal peak most probably are due to other sources than chicken meat consumption. These findings warrant further wgMLST-based studies to reassess the role of other reservoirs in the Campylobacter epidemiology both in Finland and elsewhere.

Activities of telithromycin, erythromycin, fluoroquinolones, and doxycycline against Campylobacter strains isolated from Finnish subjects.

The in vitro susceptibilities of 478 Campylobacter jejuni and Campylobacter coli strains isolated from Finnish subjects during 2002 to 2004 were determined. Susceptibility to erythromycin remained high, and telithromycin did not offer any advantage over erythromycin. Reduced susceptibilities to fluoroquinolones and doxycycline were detected almost exclusively among isolates of foreign origin.

Experimental Helicobacter felis infection in transgenic mice expressing human group IIA phospholipase A2.

BACKGROUND: Both various virulence factors of Helicobacter pylori and host factors influence the clinical outcome of H. pylori infection. In animal experiments with Helicobacter felis, large variations in the severity of disease have been observed between different mouse strains infected with a single isolate of H. felis. C57BL/6 J mouse strain that lacks the expression of group IIA phospholipase A2 has been shown to develop more severe gastric inflammation than other mouse strains. Thus, group IIA phospholipase A2 has been suggested to play a role in regulating inflammation in gastric mucosa. The aim of this study was to examine the possible role of group IIA phospholipase A2 in experimental Helicobacter infection. MATERIALS AND METHODS: Transgenic mice expressing human group IIA phospholipase A2 and their group IIA phospholipase A2 deficient nontransgenic C57BL/6 J littermates were infected with H. felis. The mice were killed 3, 8, and 19 weeks after inoculation of bacteria to determine the histopathological changes in gastric mucosa. RESULTS: The infected mice developed chronic inflammation in gastric mucosa. We found no differences in the colonization of bacteria between transgenic and nontransgenic mice. At 3 and 8 weeks, no difference was found in the severity of inflammation between the two groups. Nineteen weeks after the administration of bacteria the inflammation was more marked in nontransgenic than transgenic mice. Group IIA phospholipase A2 was expressed by in situ hybridization in the neck cells of the glandular stomach in transgenic mice. CONCLUSIONS: The results of the present study suggest that the endogenous expression of group IIA phospholipase A2 diminishes chronic inflammation in gastric mucosa in experimental H. felis infection in mice.