Longitudinal study of the effect of a 5-year exercise intervention on structural brain complexity in older adults. A Generation 100 substudy

Physical inactivity has been identified as an important risk factor for dementia. High levels of cardiorespiratory fitness (CRF) have been shown to reduce the risk of dementia. However, the mechanism by which exercise affects brain health is still debated. Fractal dimension (FD) is an index that quantifies the structural complexity of the brain. The purpose of this study was to investigate the effects of a 5-year exercise intervention on the structural complexity of the brain, measured through the FD, in a subset of 105 healthy older adults participating in the randomized controlled trial Generation 100 Study. The subjects were randomized into control, moderate intensity continuous training, and high intensity interval training groups. Both brain MRI and CRF were acquired at baseline and at 1-, 3- and 5-years follow-ups. Cortical thickness and volume data were extracted with FreeSurfer, and FD of the cortical lobes, cerebral and cerebellar gray and white matter were computed. CRF was measured as peak oxygen uptake (VO2peak) using ergospirometry during graded maximal exercise testing. Linear mixed models were used to investigate exercise group differences and possible CRF effects on the brain's structural complexity. Associations between change over time in CRF and FD were performed if there was a significant association between CRF and FD. There were no effects of group membership on the structural complexity. However, we found a positive association between CRF and the cerebral gray matter FD (p < 0.001) and the temporal lobe gray matter FD (p < 0.001). This effect was not present for cortical thickness, suggesting that FD is a more sensitive index of structural changes. The change over time in CRF was associated with the change in temporal lobe gray matter FD from baseline to 5-year follow-up (p < 0.05). No association of the change was found between CRF and cerebral gray matter FD. These results demonstrated that entering old age with high and preserved CRF levels protected against loss of structural complexity in areas sensitive to aging and age-related pathology

Seroprevalence of Toxoplasma gondii in domestic pigs, sheep, cattle, wild boars, and moose in the Nordic-Baltic region: A systematic review and meta-analysis : Parasite Epidemiology and Control

Background: Toxoplasma gondii is an important foodborne zoonotic parasite. Meat of infected animals is presumed to constitute a major source of human infection and may be a driver of geographical variation in the prevalence of anti-T. gondii antibodies in humans, which is substantial in the Nordic-Baltic region in northern Europe. However, data on seroprevalence of T. gondii in different animal species used for human consumption are scattered. Methods: We conducted a systematic review of seroprevalence studies and meta-analysis to estimate the seroprevalence of T. gondii in five animal species that are raised or hunted for human consumption in the Nordic-Baltic region: domestic pigs (Sus scrofa domesticus), sheep (Ovis aries), cattle (Bos taurus), wild boars (Sus scrofa), and moose (Alces alces). We searched for studies that were conducted between January 1990 and June 2018, and reported in articles, theses, conference abstracts and proceedings, and manuscripts. Subgroup analyses were performed to identify variables influencing the seroprevalence. Findings: From a total of 271 studies identified in the systematic review, 32 were included in the meta-analysis. These comprised of 13 studies on domestic pigs, six on sheep, three on cattle, six on wild boars, and four on moose. The estimated pooled seroprevalence of T. gondii was 6% in domestic pigs (CI 95% : 3–10%), 23% in sheep (CI 95% : 12–36%), 7% in cattle (CI 95% : 1–21%), 33% in wild boars (CI 95% : 26–41%), and 16% in moose (CI 95% : 10–23%). High heterogeneity was observed in the seroprevalence data within each species. In all host species except wild boars, the pooled seroprevalence estimates were significantly higher in animals >1 year of age than in younger animals. Not all studies provided information on animal age, sensitivity and specificity of the serological method employed, and the cut-off values used for defining an animal seropositive. Conclusions: A substantial proportion of animals raised or hunted for human consumption in the region had tested positive for T. gondii. This indicates widespread exposure to T. gondii among animals raised or hunted for human consumption in the region. Large variations were observed in the seroprevalence estimates between the studies in the region; however, studies were too few to identify spatial patterns at country-level. © 2019Peer reviewe

Stool Microbiota Diversity Analysis of Blastocystis-Positive and Blastocystis-Negative Individuals

Blastocystis is a unicellular eukaryote found in the gastrointestinal tract of both human and other animal hosts. The clinical significance of colonic Blastocystis colonization remains obscure. In this study, we used metabarcoding and bioinformatics analyses to identify differences in stool microbiota diversity between Blastocystis-positive and Blastocystis-negative individuals (n = 1285). Alpha diversity was significantly higher in Blastocystis carriers. At phylum level, Firmicutes and Bacteroidetes were enriched in carriers, while Proteobacteria were enriched in non-carriers. The genera Prevotella, Faecalibacterium, Flavonifracter, Clostridium, Succinivibrio, and Oscillibacter were enriched in carriers, whereas Escherichia, Bacteroides, Klebsiella, and Pseudomonas were enriched in non-carriers. No difference in beta diversity was observed. Individuals with Blastocystis-positive stools appear to have gut microbiomes associated with eubiosis unlike those with Blastocystis-negative stools, whose gut microbiomes are similar to those associated with dysbiosis. The role of Blastocystis as an indicator organism and potential modulator of the gut microbiota warrants further scrutiny.publishedVersio

Nonfasting triglycerides and risk of cardiovascular death in men and women from the Norwegian Counties Study

The association between nonfasting triglycerides and cardiovascular disease (CVD) has recently been actualized. The aim of the present study was to investigate nonfasting triglycerides as a predictor of CVD mortality in men and women. A total of 86,261 participants in the Norwegian Counties Study 1974–2007, initially aged 20–50 years and free of CVD were included. We estimated hazard ratios (HRs) for deaths from CVD, ischemic heart disease (IHD), stroke and all causes by level of nonfasting triglycerides. Mean follow-up was 27.0 years. A total of 9,528 men died (3,620 from CVD, 2,408 IHD, 543 stroke), and totally 5,267 women died (1,296 CVD, 626 IHD, 360 stroke). After adjustment for CVD risk factors other than HDL-cholesterol, the HRs (95% CI) per 1 mmol/l increase in nonfasting triglycerides were 1.16 (1.13–1.20), 1.20 (1.14–1.27), 1.26 (1.19–1.34) and 1.09 (0.96–1.23) for all cause mortality, CVD, IHD, and stroke mortality in women. Corresponding figures in men were 1.03 (1.01–1.04), 1.03 (1.00–1.05), 1.03 (1.00–1.06) and 0.99 (0.92–1.07). In a subsample where HDL-cholesterol was measured (n = 40,144), the association between CVD mortality and triglycerides observed in women disappeared after adjustment for HDL-cholesterol. In a model including the Framingham CHD risk score the effect of triglycerides disappeared in both men and women. In conclusion, nonfasting triglycerides were associated with increased risk of CVD death for both women and men. Adjustment for major cardiovascular risk factors, however, attenuated the effect. Nonfasting triglycerides added no predictive information on CVD mortality beyond the Framingham CHD risk score in men and women

Even low level of physical activity is associated with reduced mortality among people with metabolic syndrome, a population based study (the HUNT 2 study, Norway)

<p>Abstract</p> <p>Background</p> <p>Low levels of physical activity may increase the risk of developing metabolic syndrome, a cluster of metabolic factors that are associated with the risk of premature death. It has been suggested that physical activity may reduce the impact of factors associated with metabolic syndrome, but it is not known whether physical activity may reduce mortality in people with metabolic syndrome.</p> <p>Methods</p> <p>In a prospective study of 50,339 people, 13,449 had metabolic syndrome at baseline and were followed up for ten years to assess cause-specific mortality. The population was divided into two age groups: those younger than 65 years of age and those older than age 65. Information on their physical activity levels was collected at baseline.</p> <p>Results</p> <p>Metabolic syndrome was associated with higher mortality from all causes (hazard ratio (HR) 1.35, 95% confidence interval (95% CI) 1.20 to 1.52) and from cardiovascular causes (HR 1.78, 95% CI 1.39 to 2.29) in people younger than 65 years old than among other populations. In older people, there was no overall association of metabolic syndrome with mortality. People with metabolic syndrome who reported high levels of physical activity at baseline were at a reduced risk of death from all causes compared to those who reported no physical activity, both in the younger age group (HR 0.52, 95% CI 0.37 to 0.73) and in the older age group (HR 0.59, 95% CI 0.47 to 0.74).</p> <p>Conclusion</p> <p>Among people with metabolic syndrome, physical activity was associated with reduced mortality from all causes and from cardiovascular causes. Compared to inactivity, even low levels of physical activity were associated with reduced mortality.</p

Comparison of Methods for Detection of Blastocystis Infection in Routinely Submitted Stool Samples, and also in IBS/IBD Patients in Ankara, Turkey

BACKGROUND: This study compared diagnostic methods for identifying Blastocystis in stool samples, and evaluated the frequency of detection of Blastocystis in patients with irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). RESULTS AND DISCUSSION: From a set of 105 stool specimens submitted for routine parasitological analysis, 30 were identified as positive for Blastocystis by the culture method. From that group of 30 positives, Lugol's stain, trichrome staining, and an immunofluorescence assay identified 11, 15, and 26 samples as positive respectively. Using culture as a standard, the sensitivity of Lugol's stain was 36.7%, trichrome staining was 50%, and the IFA stain was 86.7%. The specificity of Lugol's stain was 91%, trichrome staining was 100%, and the IFA stain was 97.3%. In the group of 27 IBS and IBD patients, using all methods combined, we detected Blastocystis in 67% (18/27) of the patients. Blastocystis was detected in 33% (2/6) of IBD patients and 76% (16/21) of IBS patients. For comparison, trichrome staining alone, the method most frequently used in many countries, would have only identified Blastocystis infection in 29% (6/21) of the IBS patients. No parasitic co-infections were identified in the IBS/IBD patients. Most Blastocystis-positive IBS/IBD patients were over 36 with an average length of illness of 4.9 years. CONCLUSIONS: Most IBS patients in this study were infected with Blastocystis. IFA staining may be a useful alternative to stool culture, especially if stool specimens have been chemically preserved

New Insights into Blastocystis spp.: A Potential Link with Irritable Bowel Syndrome

International audienceBlastocystis spp. belong to the phylum Stramenopila, a complex and heterogeneous evolutionary assemblage of heterotrophic and photosynthetic protozoa [1]. Interestingly, this is the only stramenopile living in the lower digestive tract of humans, and it also lives in other mammals, birds, reptiles, amphibians, and insects [1]. Even though isolates were reported to be morphologically indistinguishable, an extensive genetic variation among isolates from both humans and animals has been observed. Thirteen subtypes (ST1-ST13), with the first nine being found in humans, have been identified based on genes coding for the small-subunit ribosomal RNA [2]. Preferential repartition of STs exists among animals that appear to constitute the main reservoir for environmental dissemination and human contamination