Forever young(er): potential age-defying effects of long-term meditation on gray matter atrophy

While overall life expectancy has been increasing, the human brain still begins deteriorating after the first two decades of life and continues degrading further with increasing age. Thus, techniques that diminish the negative impact of aging on the brain are desirable. Existing research, although scarce, suggests meditation to be an attractive candidate in the quest for an accessible and inexpensive, efficacious remedy. Here, we examined the link between age and cerebral gray matter re-analyzing a large sample (n = 100) of long-term meditators and control subjects aged between 24 and 77 years. When correlating global and local gray matter with age, we detected negative correlations within both controls and meditators, suggesting a decline over time. However, the slopes of the regression lines were steeper and the correlation coefficients were stronger in controls than in meditators. Moreover, the age-affected brain regions were much more extended in controls than in meditators, with significant group-by-age interactions in numerous clusters throughout the brain. Altogether, these findings seem to suggest less age-related gray matter atrophy in long-term meditation practitioners.Nicolas Cherbuin is funded by Australian Research Council fellowship number 120100227

Meditation effects within the hippocampal complex revealed by voxel-based morphometry and cytoarchitectonic probabilistic mapping.

Scientific studies addressing anatomical variations in meditators' brains have emerged rapidly over the last few years, where significant links are most frequently reported with respect to gray matter (GM). To advance prior work, this study examined GM characteristics in a large sample of 100 subjects (50 meditators, 50 controls), where meditators have been practicing close to 20 years, on average. A standard, whole-brain voxel-based morphometry approach was applied and revealed significant meditation effects in the vicinity of the hippocampus, showing more GM in meditators than in controls as well as positive correlations with the number of years practiced. However, the hippocampal complex is regionally segregated by architecture, connectivity, and functional relevance. Thus, to establish differential effects within the hippocampal formation (cornu ammonis, fascia dentata, entorhinal cortex, subiculum) as well as the hippocampal-amygdaloid transition area, we utilized refined cytoarchitectonic probabilistic maps of (peri-) hippocampal subsections. Significant meditation effects were observed within the subiculum specifically. Since the subiculum is known to play a key role in stress regulation and meditation is an established form of stress reduction, these GM findings may reflect neuronal preservation in long-term meditators-perhaps due to an attenuated release of stress hormones and decreased neurotoxicity

The impact of aging on subregions of the hippocampal complex in healthy adults

The hippocampal complex, an anatomical composite of several subregions, is known to decrease in size with increasing age. However, studies investigating which subregions are particularly prone to age-related tissue loss revealed conflicting findings. Possible reasons for such inconsistencies may reflect differences between studies in terms of the cohorts examined or techniques applied to define and measure hippocampal subregions. In the present study, we enhanced conventional MR-based information with microscopically defined cytoarchitectonic probabilities to investigate aging effects on the hippocampal complex in a carefully selected sample of 96 healthy subjects (48 males/48 females) aged 18-69 years. We observed significant negative correlations between age and volumes of the cornu ammonis, fascia dentata, subiculum, and hippocampal-amygdaloid transition area, but not the entorhinal cortex. The estimated age-related annual atrophy rates were most pronounced in the left and right subiculum with -0.23% and -0.22%, respectively. These findings suggest age-related atrophy of the hippocampal complex overall, but with differential effects in its subregions. If confirmed in future studies, such region-specific information may prove useful for the assessment of diseases and disorders known to modulate age-related hippocampal volume loss.NC is funded by Australian Research Council Future fellowship number 120100227. EL is funded by the Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health under award number R01HD081720 and further supported by the Cousins Center for Psychoneuroimmunology at the University of California, Los Angeles (UCLA)

Intravenous Artesunate Reduces Parasite Clearance Time, Duration of Intensive Care, and Hospital Treatment in Patients With Severe Malaria in Europe: The TropNet Severe Malaria Study

Intravenous artesunate improves survival in severe malaria, but clinical trial data from nonendemic countries are scarce. The TropNet severe malaria database was analyzed to compare outcomes of artesunate vs quinine treatment. Artesunate reduced parasite clearance time and duration of intensive care unit and hospital treatment in European patients with imported severe malari

Continuous Noninvasive Monitoring of Lung Recruitment during High-Frequency Oscillatory Ventilation by Electrical Impedance Measurement: An Animal Study

Background: Ventilatory pressures should target the range between the upper and lower inflection point of the pressure volume curve in order to avoid atelecto- and volutrauma. During high-frequency oscillatory ventilation (HFOV), this range is difficult to determine. Quadrant impedance measurement (QIM) has recently been shown to allow accurate and precise measurement of lung volume changes during conventional mechanical ventilation. Objectives: To investigate if QIM can be used to determine a static pressure-residual impedance curve during a recruitment-derecruitment manoeuvre on HFOV and to monitor the time course of alveolar recruitment after changing mean airway pressure (MAP). Methods: An incremental and decremental MAP trial (6 cm H₂O to 27 cm H₂O) was conducted in five surfactantdepleted newborn piglets during HFOV. Ventilatory, gas exchange and haemodynamic parameters were recorded. Continuous measurement of thoracic impedance change was performed. Results: Mean residual impedance (RI) increased with each stepwise increase of MAP resulting in a total mean increase of +26.5% (±4.0) at the highest MAP (27 cm H₂O) compared to baseline ventilation at 6 cm H₂O. Upon decreasing MAP levels, RI fell more slowly compared to its ascent; 83.4% (±19.1) and 84.8% (±16.4) of impedance changes occurred in the first 5 min after an increase or decrease in airway pressure, respectively. Conclusions: QIM could be used for continuous monitoring of thoracic impedance and determination of the pressure-RI curve during HFOV. The method could prove to be a promising bedside method for the monitoring of lung recruitment during HFOV in the future

Schistosomiasis in European Travelers and Migrants: Analysis of 14 Years TropNet Surveillance Data

Schistosomiasis; Travelers and migrants; EuropeEsquistosomosi; Viatgers i migrants; EuropaEsquistosomiasis; Viajeros y migrantes; EuropaSchistosomiasis remains one of the most prevalent parasitic diseases worldwide and the infection is frequently found in travelers and migrants. The European Network for Tropical Medicine and Travel Health conducted a sentinel surveillance study on imported schistosomiasis between 1997 and 2010. This report summarizes epidemiological and clinical data from 1,465 cases of imported schistosomiasis. Direct pathogen detection and serology were the main diagnostic tools applied. Of these, 486 (33%) cases were identified among European travelers, 231 (16%) among long-term expatriates, and 748 (51%) among non-European immigrants. Overall, only 18.6% of travelers had received pretravel advice; 95% of infections were acquired in the African region. On species level, Schistosoma mansoni was identified in 570 (39%) and Schistosoma haematobium in 318 (22%) cases; 57.5% of patients were symptomatic. Acute symptoms were reported in 27% of patients leading to earlier presentation within 3 months. Praziquantel was used in all patients to treat schistosomiasis. Many infections were detected in asymptomatic patients. In 47.4% of asymptomatic patients infection was detected by microscopy and in 39% by serology or antigen testing. Schistosomiasis remains a frequent infection in travelers and migrants to Europe. Travelers should be made aware of the risk of schistosomiasis infection when traveling to sub-Saharan Africa. Posttravel consultations particularly for returning expatriates are useful given the high potential for detecting asymptomatic infections

an 8-year multi-centre observational study

Background Malaria remains one of the most serious infections for travellers to tropical countries. Due to the lack of harmonized guidelines a large variety of treatment regimens is used in Europe to treat severe malaria. Methods The European Network for Tropical Medicine and Travel Health (TropNet) conducted an 8-year, multicentre, observational study to analyse epidemiology, treatment practices and outcomes of severe malaria in its member sites across Europe. Physicians at participating TropNet centres were asked to report pseudonymized retrospective data from all patients treated at their centre for microscopically confirmed severe Plasmodium falciparum malaria according to the 2006 WHO criteria. Results From 2006 to 2014 a total of 185 patients with severe malaria treated in 12 European countries were included. Three patients died, resulting in a 28-day survival rate of 98.4%. The majority of infections were acquired in West Africa (109/185, 59%). The proportion of patients treated with intravenous artesunate increased from 27% in 2006 to 60% in 2013. Altogether, 56 different combinations of intravenous and oral drugs were used across 28 study centres. The risk of acute renal failure (36 vs 17% p = 0.04) or cerebral malaria (54 vs 20%, p = 0.001) was significantly higher in patients ≥60 years than in younger patients. Respiratory distress with the need for mechanical ventilation was significantly associated with the risk of death in the study population (13 vs 0%, p = 0.001). Post-artemisinin delayed haemolysis was reported in 19/70 (27%) patients treated with intravenous artesunate. Conclusion The majority of patients with severe malaria in this study were tourists or migrants acquiring the infection in West Africa. Intravenous artesunate is increasingly used for treatment of severe malaria in many European treatment centres and can be given safely to European patients with severe malaria. Patients treated with intravenous artesunate should be followed up to detect and manage late haemolytic events

The Unique Brain Anatomy of Meditation Practitioners: Alterations in Cortical Gyrification

Several cortical regions are reported to vary in meditation practitioners. However, prior analyses have focused primarily on examining gray matter or cortical thickness. Thus, additional effects with respect to other cortical features might have remained undetected. Gyrification (the pattern and degree of cortical folding) is an important cerebral characteristic related to the geometry of the brain’s surface. Thus, exploring cortical gyrification in long-term meditators may provide additional clues with respect to the underlying anatomical correlates of meditation. This study examined cortical gyrification in a large sample (n = 100) of meditators and controls, carefully matched for sex and age. Cortical gyrification was established by calculating mean curvature across thousands of vertices on individual cortical surface models. Pronounced group differences indicating larger gyrification in meditators were evident within the left precentral gyrus, right fusiform gyrus, right cuneus, as well as left and right anterior dorsal insula (the latter representing the global significance maximum). Positive correlations between gyrification and the number of meditation years were similarly pronounced in the right anterior dorsal insula. Although the exact functional implications of larger cortical gyrification remain to be established, these findings suggest the insula to be a key structure involved in aspects of meditation. For example, variations in insular complexity could affect the regulation of well-known distractions in the process of meditation, such as daydreaming, mind-wandering, and projections into past or future. Moreover, given that meditators are masters in introspection, awareness, and emotional control, increased insular gyrification may reflect an integration of autonomic, affective, and cognitive processes. Due to the cross-sectional nature of this study, further research is necessary to determine the relative contribution of nature and nurture to links between cortical gyrification and meditation