Human B19 parvovirus infetion: an example of multiple pathogenic effects determined by differences in host susceptibility

B19 infection offers some general lessons about human viruses and their possible effects on the human host, as follows: (1) Ubiquitous apparently benign viruses may have severe effects on a compromissed host. The virus may be invariable but the host can have diverse susceptibilities. (2) B19 and some other human viruses (through for none is the evidence so clear as for B19) have narrowly targetted effects. The host cell of B19 is a specialised progenitor of mature red cells: impairment of the function of this cell by B19 may cause profound anaemia. (3) The 'normal'host response to B19 may also cause disease, though this is slef limiting. (4) The effects of malfunction of the virus'target cell are exacerbated when the immune response is impaired by congenital or acquired immunodeficiency, immunosupressive therapy or, in the case of the fetus, developmental immaturity that allows the virus to persist.

Differences in self-reported prevalence and management of cardiovascular risk factors in Switzerland, 2007

Purpose: To assess the prevalence of four self-reported cardiovascular risk factors (CV RFs: smoking, hypertension, dyslipidaemia and diabetes) and their reported management in seven Swiss regions (Léman, MiUelland, Zurich, North-West Switzerland, Oriental Switzerland, Central Switzerland and Tessin). Methods: National health interview survey conducted in 2007 in a representative sample of the Swiss population (17,879 subjects). Age-adjusted data on prevalence of self-reported CV RFs, treatment among participants reporting a RF, control of RFs among treated participants and CV RF screening in the last 12 months levels were computed after weighting. Results: The prevalence of hypertension was highest in North-West Switzerland (27.3%) and lowest in Central Switzerland (21.0%, p<0.001). Antihypertensive treatment was highest in Léman region (62.7%) and lowest in Oriental Switzerland (55.2%, p<0.001). Screening was higher in Tessin (89.3%) and lowest in Léman region (81.8%, p<0.001). Prevalence of dyslipidaemia was highest in Tessin and Léman region (20.7% and 20.1 %, respectively) and lowest in Oriental Switzerland (14.5%, p<0.001). Lipid-Iowering treatment was highest in Tessin and Léman region (44.3% each) and lowest in Central Switzerland (30.7%, p<0.001). Dyslipidaemia screening was highest in Tessin (76.6%) and lowest in Central Switzerland (58.6%, p<0.001). Prevalence of diabetes was highest in North-West Switzerland (5.4%) and lowest in Central Switzerland (3.3%, p<0.05). Diabetes screening was highest in Tessin (78.1%) and lowest in Oriental Switzerland (64.0%, p<0.001). Conversely, no between-region differences were found for hypertension or dyslipidaemia control (see table). Conclusion: there are significant differences between the Swiss regions in self-reported prevalence and management of CV RFs. Screening is beUer in Tessin than in the other regions.

Adapting dating violence prevention to francophone Switzerland: a story of intra-western cultural differences.

Dating violence prevention programs, which originated in the United States, are beginning to be implemented elsewhere. This article presents the first adaptation of a violence prevention program for a European culture, Francophone Switzerland. A U.S. dating violence prevention program, Safe Dates (Foshee & Langwick, 1994), was reviewed in 19 youth and 4 professional focus groups. The most fundamental program concepts--"dating" and "violence"--are not the same in Switzerland and the United States. Swiss youth were not very focused on establishing monogamous romantic relationships, and there is no ready translation for "dating." Violence has not become the focus of a social movement in Switzerland to the same extent that it has in the United States, and distinctions among terms such as "dating violence" and "domestic violence" are not well known. Psychoeducational approaches are also less common in the Swiss context. As the movement to prevent violence extends worldwide, these issues need greater consideration.

Etiology of ethnic differences in childhood spirometry.

OBJECTIVES: Age- and height-adjusted spirometric lung function of South Asian children is lower than those of white children. It is unclear whether this is purely genetic, or partly explained by the environment. In this study, we assessed whether cultural factors, socioeconomic status, intrauterine growth, environmental exposures, or a family and personal history of wheeze contribute to explaining the ethnic differences in spirometric lung function. METHODS: We studied children aged 9 to 14 years from a population-based cohort, including 1088 white children and 275 UK-born South Asians. Log-transformed spirometric data were analyzed using multiple linear regressions, adjusting for anthropometric factors. Five different additional models adjusted for (1) cultural factors, (2) indicators of socioeconomic status, (3) perinatal data reflecting intrauterine growth, (4) environmental exposures, and (5) personal and family history of wheeze. RESULTS: Height- and gender-adjusted forced vital capacity (FVC) and forced expired volume in 1 second (FEV1) were lower in South Asian than white children (relative difference -11% and -9% respectively, P < .001), but PEF and FEF50 were similar (P ≥ .5). FEV1/FVC was higher in South Asians (1.8%, P < .001). These differences remained largely unchanged in all 5 alternative models. CONCLUSIONS: Our study confirmed important differences in lung volumes between South Asian and white children. These were not attenuated after adjustment for cultural and socioeconomic factors and intrauterine growth, neither were they explained by differences in environmental exposures nor a personal or family history of wheeze. This suggests that differences in lung function may be mainly genetic in origin. The implication is that ethnicity-specific predicted values remain important specifically for South Asian children.

Physiological differences between cycling and running: lessons from triathletes

The purpose of this review was to provide a synopsis of the literature concerning the physiological differences between cycling and running. By comparing physiological variables such as maximal oxygen consumption (V O(2max)), anaerobic threshold (AT), heart rate, economy or delta efficiency measured in cycling and running in triathletes, runners or cyclists, this review aims to identify the effects of exercise modality on the underlying mechanisms (ventilatory responses, blood flow, muscle oxidative capacity, peripheral innervation and neuromuscular fatigue) of adaptation. The majority of studies indicate that runners achieve a higher V O(2max) on treadmill whereas cyclists can achieve a V O(2max) value in cycle ergometry similar to that in treadmill running. Hence, V O(2max) is specific to the exercise modality. In addition, the muscles adapt specifically to a given exercise task over a period of time, resulting in an improvement in submaximal physiological variables such as the ventilatory threshold, in some cases without a change in V O(2max). However, this effect is probably larger in cycling than in running. At the same time, skill influencing motor unit recruitment patterns is an important influence on the anaerobic threshold in cycling. Furthermore, it is likely that there is more physiological training transfer from running to cycling than vice versa. In triathletes, there is generally no difference in V O(2max) measured in cycle ergometry and treadmill running. The data concerning the anaerobic threshold in cycling and running in triathletes are conflicting. This is likely to be due to a combination of actual training load and prior training history in each discipline. The mechanisms surrounding the differences in the AT together with V O(2max) in cycling and running are not largely understood but are probably due to the relative adaptation of cardiac output influencing V O(2max) and also the recruitment of muscle mass in combination with the oxidative capacity of this mass influencing the AT. Several other physiological differences between cycling and running are addressed: heart rate is different between the two activities both for maximal and submaximal intensities. The delta efficiency is higher in running. Ventilation is more impaired in cycling than in running. It has also been shown that pedalling cadence affects the metabolic responses during cycling but also during a subsequent running bout. However, the optimal cadence is still debated. Central fatigue and decrease in maximal strength are more important after prolonged exercise in running than in cycling.

Minimal clinically meaningful differences for the eortc QLQ-C30 and eortc QLQ-Bn20 scales in brain cancer patients

Objective: The aim of this study was to determine the smallest changes in health-related quality of life (HRQOL) scores in the European Organization for Research and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30) and the EORTC Brain Cancer Module (QLQ-BN20), which could be considered as clinically meaningful in brain cancer patients. Methods: World Health Organization (WHO) performance status (PS) and the Mini Mental State Examination (MMSE) were used as clinical anchors to determine minimal clinically important differences (MCID) in HRQOL change scores (range 0 - 100) in the EORTC QLQ-C30 and QLQ-BN20. Anchor-based MCID estimates less than 0.2SD (small effect) were not recommended for interpretation. Other selected distribution-based methods were also used for comparison purposes. Results: Based on WHO PS, our findings support the following whole number estimates of the MCID for improvement and deterioration respectively: physical functioning (6, 9), role functioning (14, 12), cognitive functioning (8, 8), global health status (7, 4*), fatigue (12, 9) and motor dysfunction (4*, 5). Anchoring with MMSE, cognitive functioning MCID estimates for improvement and deterioration were (11, 2*) and those for communication deficit were (9, 7). The estimates with asterisks were less that the set 0.2 SD threshold and are therefore not recommended for interpretation. Our MCID estimates therefore range from 5-14. Conclusion: These estimates can help clinicians to evaluate changes in HRQOL over time and, in conjunction with other measures of efficacy, help to assess the value of a health care intervention or to compare treatments. Furthermore, the estimates can be useful in determining sample sizes in the design of future clinical trials.

Work, risk and health: differences between immigrants and natives in Spain

We analyze the impact of working and contractual conditions, particularly exposure to job risks, on the probability of acquiring a disability. We postulate a model in which this impact is mediated by the choice of occupation, with a level of risk associated to it. We assume this choice is endogenous, and that it depends on preferences and opportunities in the labour market, both of which may differ between immigrants and natives. To test this hypothesis we use data from the Continuous Sample of Working Lives of the Spanish SS system. It contains individual, job and firm information of over a million workers, including a representative sample of immigrants. We find that risk exposure increases the probability of permanent disability by 5.3%; temporary employment also influences health. Migrant status -with differences among regions of origin- significantly affects both disability and the probability of being employed in a risky occupation. Most groups of immigrants work in riskier jobs, but have lower probability of becoming disabled. Nevertheless, our theoretical hypothesis that disability and risk are jointly determined is not valid for immigrants: i.e. for them working conditions is not a matter of choice in terms of health.

Oxidative stress and inflammation response after nanoparticle exposure : differences between human lung cell monocultures and an advanced three-dimensional model of the human epithelial airways

Combustion-derived and manufactured nanoparticles (NPs) are known to provoke oxidative stress and inflammatory responses in human lung cells; therefore, they play an important role during the development of adverse health effects. As the lungs are composed of more than 40 different cell types, it is of particular interest to perform toxicological studies with co-cultures systems, rather than with monocultures of only one cell type, to gain a better understanding of complex cellular reactions upon exposure to toxic substances. Monocultures of A549 human epithelial lung cells, human monocyte-derived macrophages and monocyte-derived dendritic cells (MDDCs) as well as triple cell co-cultures consisting of all three cell types were exposed to combustion-derived NPs (diesel exhaust particles) and to manufactured NPs (titanium dioxide and single-walled carbon nanotubes). The penetration of particles into cells was analysed by transmission electron microscopy. The amount of intracellular reactive oxygen species (ROS), the total antioxidant capacity (TAC) and the production of tumour necrosis factor (TNF)-a and interleukin (IL)-8 were quantified. The results of the monocultures were summed with an adjustment for the number of each single cell type in the triple cell co-culture. All three particle types were found in all cell and culture types. The production of ROS was induced by all particle types in all cell cultures except in monocultures of MDDCs. The TAC and the (pro-)inflammatory reactions were not statistically significantly increased by particle exposure in any of the cell cultures. Interestingly, in the triple cell co-cultures, the TAC and IL-8 concentrations were lower and the TNF-a concentrations were higher than the expected values calculated from the monocultures. The interplay of different lung cell types seems to substantially modulate the oxidative stress and the inflammatory responses after NP exposure. [Authors]

Differences in the transduction of canonical wnt signals demarcate effector and memory CD8 T cells with distinct recall proliferation capacity.

Protection against reinfection is mediated by Ag-specific memory CD8 T cells, which display stem cell-like function. Because canonical Wnt (Wingless/Int1) signals critically regulate renewal versus differentiation of adult stem cells, we evaluated Wnt signal transduction in CD8 T cells during an immune response to acute infection with lymphocytic choriomeningitis virus. Whereas naive CD8 T cells efficiently transduced Wnt signals, at the peak of the primary response to infection only a fraction of effector T cells retained signal transduction and the majority displayed strongly reduced Wnt activity. Reduced Wnt signaling was in part due to the downregulation of Tcf-1, one of the nuclear effectors of the pathway, and coincided with progress toward terminal differentiation. However, the correlation between low and high Wnt levels with short-lived and memory precursor effector cells, respectively, was incomplete. Adoptive transfer studies showed that low and high Wnt signaling did not influence cell survival but that Wnt high effectors yielded memory cells with enhanced proliferative potential and stronger protective capacity. Likewise, following adoptive transfer and rechallenge, memory cells with high Wnt levels displayed increased recall expansion, compared with memory cells with low Wnt signaling, which were preferentially effector-like memory cells, including tissue-resident memory cells. Thus, canonical Wnt signaling identifies CD8 T cells with enhanced proliferative potential in part independent of commonly used cell surface markers to discriminate effector and memory T cell subpopulations. Interventions that maintain Wnt signaling may thus improve the formation of functional CD8 T cell memory during vaccination.

Same wording, distinct concepts? Testing differences between expectancies and motives in a mediation model of alcohol outcomes.

Per definition, alcohol expectancies (after alcohol I expect X), and drinking motives (I drink to achieve X) are conceptually distinct constructs. Theorists have argued that motives mediate the association between expectancies and drinking outcomes. Yet, given the use of different instruments, do these constructs remain distinct when assessment items are matched? The present study tested to what extent motives mediated the link between expectancies and alcohol outcomes when identical items were used, first as expectancies and then as motives. A linear structural equation model was estimated based on a national representative sample of 5,779 alcohol-using students in Switzerland (mean age = 15.2 years). The results showed that expectancies explained up to 38% of the variance in motives. Together with motives, they explained up to 48% of the variance in alcohol outcomes (volume, 5+ drinking, and problems). In 10 of 12 outcomes, there was a significant mediated effect that was often higher than the direct expectancy effect. For coping, the expectancy effect was close to zero, indicating the strongest form of mediation. In only one case (conformity and 5+ drinking), there was a direct expectancy effect but no mediation. To conclude, the study demonstrates that motives are distinct from expectancies even when identical items are used. Motives are more proximally related to different alcohol outcomes, often mediating the effects of expectancies. Consequently, the effectiveness of interventions, particularly those aimed at coping drinkers, should be improved through a shift in focus from expectancies to drinking motives.