A schizophrenia locus may be located in region 10p15-p11

In our genomic scan of 265 Irish families with schizophrenia, we have thus far generated modest evidence for the presence of vulnerability genes in three chromosomal regions, i.e., 5q21-q31, 6p24-p22, and 8p22-p21. Outside of those regions, of all markers tested to date, D10S674 produced one of the highest pairwise heterogeneity lod (H-LOD) scores, 3.2 (P = 0.0004), when initially tested on a subset of 88 families. We then tested a total of 12 markers across a region of 32 centimorgans in region 10p15-p11 of all 265 families. The strongest evidence for linkage occurred assuming an intermediate phenotypic definition, and a recessive genetic model. The largest pairwise H-LOD score was found with marker D10S2443 (maximum 1.95, P = 0.005). Using multipoint H-LODs, we found a broad peak (maximum 1.91, P = 0.006) extending over the 11 centimorgans from marker D10S674 to marker D10S1426. Multipoint nonparametric linkage analysis produced a much broader peak, but with the maximum in the same location near D10S2443 (maximum z = 1.88, P = 0.03). Based on estimates from the multipoint analysis, this putative vulnerability locus appears to be segregating in 5-15% of the families studied, but this estimate should be viewed with caution. When evaluated in the context of our genome scan results, the evidence suggests the possibility of a fourth vulnerability locus for schizophrenia in these Irish families, in region 10p15-p11.

Abstinence from alcohol may indeed be the best policy: 32 month longitudinal outcomes among adolescents in the United Kingdom.

The present study investigated the longitudinal relationship between alcohol consumption at age 13, and at age 16. Alcohol-specific measures were frequency of drinking, amount consumed at last use and alcohol related harms. Self-report data were gathered from 1113 high school students at T1, and 981 students at T2. Socio-demographic data were gathered, as was information on context of use, alcohol-related knowledge and attitudes, four domains of aggression and delay reward discounting. Results indicated that any consumption of alcohol, even supervised consumption, at T1 was associated with significantly poorer outcomes at T2. In other words, compared to those still abstinent at age 13, those engaging in alcohol use in any context reported significantly more frequent drinking, more alcohol-related harms and more units consumed at last use at age 16. Results also support the relationship between higher levels of physical aggression at T1 and a greater likelihood of more problematic alcohol use behaviours at T2. The findings support other evidence suggesting that abstinence in early adolescence has better longitudinal outcomes that supervised consumption of alcohol. These results suggest support for current guidance on adolescent drinking in the United Kingdom (UK).

Size matters: plasticity in metabolic scaling shows body-size may modulate responses to climate change

Variability in metabolic scaling in animals, the relationship between metabolic rate (R) and body mass (M), has been a source of debate and controversy for decades. R is proportional to M-b, the precise value of b much debated, but historically considered equal in all organisms. Recent metabolic theory, however, predicts b to vary among species with ecology and metabolic level, and may also vary within species under different abiotic conditions. Under climate change, most species will experience increased temperatures, and marine organisms will experience the additional stressor of decreased seawater pH ('ocean acidification'). Responses to these environmental changes are modulated by myriad species-specific factors. Body-size is a fundamental biological parameter, but its modulating role is relatively unexplored. Here, we show that changes to metabolic scaling reveal asymmetric responses to stressors across body-size ranges; b is systematically decreased under increasing temperature in three grazing molluscs, indicating smaller individuals were more responsive to warming. Larger individuals were, however, more responsive to reduced seawater pH in low temperatures. These alterations to the allometry of metabolism highlight abiotic control of metabolic scaling, and indicate that responses to climate warming and ocean acidification may be modulated by body-size.

Fasciola hepatica vaccine: We may not be there yet but we're on the right road

Major advances have been made in identifying potential vaccine molecules for the control of fasciolosis in livestock but we have yet to reach the level of efficacy required for commercialisation. The pathogenesis of fasciolosis is associated with liver damage that is inflicted by migrating and feeding immature flukes as well as host inflammatory immune responses to parasite-secreted molecules and tissue damage alarm signals. Immune suppression/modulation by the parasites prevents the development of protective immune responses as evidenced by the lack of immunity observed in naturally and experimentally infected animals. In our opinion, future efforts need to focus on understanding how parasites invade and penetrate the tissues of their hosts and how they potentiate and control the ensuing immune responses, particularly in the first days of infection. Emerging 'omics' data employed in an unbiased approach are helping us understand liver fluke biology and, in parallel with new immunological data, to identify molecules that are essential to parasite development and accessible to vaccine-induced immune responses.

Ultrasound entropy may be a new non-invasive measure of pre-clinical vascular damage in young hypertensive patients

Background: The identification of pre-clinical microvascular damage in hypertension by non-invasive techniques has proved frustrating for clinicians. This proof of concept study investigated whether entropy, a novel summary measure for characterizing blood velocity waveforms, is altered in participants with hypertension and may therefore be useful in risk stratification.

Methods: Doppler ultrasound waveforms were obtained from the carotid and retrobulbar circulation in 42 participants with uncomplicated grade 1 hypertension (mean systolic/diastolic blood pressure (BP) 142/92 mmHg), and 26 healthy controls (mean systolic/diastolic BP 116/69 mmHg). Mean wavelet entropy was derived from flow-velocity data and compared with traditional haemodynamic measures of microvascular function, namely the resistive and pulsatility indices.

Results: Entropy, was significantly higher in control participants in the central retinal artery (CRA) (differential mean 0.11 (standard error 0.05 cms(-1)), CI 0.009 to 0.219, p 0.017) and ophthalmic artery (0.12 (0.05), CI 0.004 to 0.215, p 0.04). In comparison, the resistive index (0.12 (0.05), CI 0.005 to 0.226, p 0.029) and pulsatility index (0.96 (0.38), CI 0.19 to 1.72, p 0.015) showed significant differences between groups in the CRA alone. Regression analysis indicated that entropy was significantly influenced by age and systolic blood pressure (r values 0.4-0.6). None of the measures were significantly altered in the larger conduit vessel.

Conclusion: This is the first application of entropy to human blood velocity waveform analysis and shows that this new technique has the ability to discriminate health from early hypertensive disease, thereby promoting the early identification of cardiovascular disease in a young hypertensive population.

Interventions Targeting Child Undernutrition in Developing Countries May Be Undermined by Dietary Exposure to Aflatoxin

Child undernutrition, a form of malnutrition, is a major public health burden in developing countries. Supplementation interventions targeting the major micronutrient deficiencies have only reduced the burden of child undernutrition to a certain extent, indicating that there are other underlying determinants that need addressed. Aflatoxin exposure, which is also highly prevalent in developing countries, may be considered to be an aggravating factor for child undernutrition. Increasing evidence suggests that aflatoxin exposure can occur in any stage of life including in utero through a trans-placental pathway and in early childhood (through contaminated weaning food and family food). Early life exposure to aflatoxin is associated with adverse effects on low birth weight, stunting, immune suppression and liver function damage. The mechanisms underlying impaired growth and aflatoxin exposure are still unclear but intestinal function damage, reduced immune function and alteration in the insulin-like growth factor axis caused by liver damage, are suggested hypotheses. Given the fact that both aflatoxin and child undernutrition are common in sub-Saharan Africa, effective interventions aimed at reducing undernutrition cannot be satisfactorily achieved until the interactive relationship between aflatoxin and child undernutrition is clearly understood, and an aflatoxin mitigation strategy has taken effect in those vulnerable mothers and children.