Big cat, small cat: reconstructing body size evolution in living and extinct Felidae

The evolution of body mass is a fundamental topic in evolutionary biology, because it is closely linked to manifold life history and ecological traits and is readily estimable for many extinct taxa. In this study, we examine patterns of body mass evolution in Felidae (Placentalia, Carnivora) to assess the effects of phylogeny, mode of evolution, and the relationship between body mass and prey choice in this charismatic mammalian clade. Our data set includes 39 extant and 26 extinct taxa, with published body mass data supplemented by estimates based on condylobasal length. These data were run through 'SURFACE' and 'bayou' to test for patterns of body mass evolution and convergence between taxa. Body masses of felids are significantly different among prey choice groupings (small, mixed and large). We find that body mass evolution in cats is strongly influenced by phylogeny, but different patterns emerged depending on inclusion of extinct taxa and assumptions about branch lengths. A single Ornstein-Uhlenbeck optimum best explains the distribution of body masses when first-occurrence data were used for the fossil taxa. However, when mean occurrence dates or last known occurrence dates were used, two selective optima for felid body mass were recovered in most analyses: a small optimum around 5 kg and a large one around 100 kg. Across living and extinct cats, we infer repeated evolutionary convergences towards both of these optima, but, likely due to biased extinction of large taxa, our results shift to supporting a Brownian motion model when only extant taxa are included in analyses.

Genetic inference of group dynamics and female kin structure in a western lowland gorilla population (<i>Gorilla gorilla gorilla</i>)

Abstract. Dispersal and grouping patterns form the foundations of social interactions in group-living mammals and are the outcomes of a complex interplay between inbreeding avoidance, kin cooperation and competition, predation pressure and food resource distribution. In species where both sexes disperse, the potential for kin-biased associations would seem limited. In one such species, the western lowland gorilla (WLG), short-term data suggest that female kin associations may be present due to directed local dispersal decisions, but monitoring of groups over longer timescales is needed to better elucidate this pattern. Using autosomal genotyping of 419 faecal samples representing 85 unhabituated gorillas collected non-invasively over 5 years in a 132 km2 section of Loango National Park, Gabon, we investigated the dynamics of WLG group composition, social structure and patterns of dispersal. By revealing two group dissolutions, one group formation and the movement of 13 gorillas between groups, this study demonstrates the utility of genetic analysis as a way to track individuals, groups and population dynamics on a larger scale than when monitoring the behaviour of a limited number of habituated groups or through one-time genetic sampling. Furthermore, we find that females are found in groups containing their female kin more often than expected by chance, suggesting that dispersal may not impede female kin associations in WLGs.

Ecogenetics of mercury: from genetic polymorphisms and epigenetics to risk assessment and decision-making

The risk assessment of mercury (Hg), in both humans and wildlife, is made challenging by great variability in exposure and health effects. Although disease risk arises following complex interactions between genetic ("nature") and environmental ("nurture") factors, most Hg studies thus far have focused solely on environmental factors. In recent years, ecogenetic-based studies have emerged and have started to document genetic and epigenetic factors that may indeed influence the toxicokinetics or toxicodynamics of Hg. The present study reviews these studies and discusses their utility in terms of Hg risk assessment, management, and policy and offers perspectives on fruitful areas for future research. In brief, epidemiological studies on populations exposed to inorganic Hg (e.g., dentists and miners) or methylmercury (e.g., fish consumers) are showing that polymorphisms in a number of environmentally responsive genes can explain variations in Hg biomarker values and health outcomes. Studies on mammals (wildlife, humans, rodents) are showing Hg exposures to be related to epigenetic marks such as DNA methylation. Such findings are beginning to increase understanding of the mechanisms of action of Hg, and in doing so they may help identify candidate biomarkers and pinpoint susceptible groups or life stages. Furthermore, they may help refine uncertainty factors and thus lead to more accurate risk assessments and improved decision-making.

Serum total hCGβ level is an independent prognostic factor in transitional cell carcinoma of the urothelial tract

Background:

Serum total human chorionic gonadotrophin β subunit (hCGβ) level might have prognostic value in urothelial transitional cell carcinoma (TCC) but has not been investigated for independence from other prognostic variables.

Methods:

We utilised a clinical database of patients receiving chemotherapy between 2005 and 2011 for urothelial TCC and an independent cohort of radical cystectomy patients for validation purposes. Prognostic variables were tested by univariate Kaplan–Meier analyses and log-rank tests. Statistically significant variables were then assessed by multivariate Cox regression. Total hCGβ level was dichotomised at < vs ⩾2 IU l⁻¹.

Results:

A total of 235 chemotherapy patients were eligible. For neoadjuvant chemotherapy, established prognostic factors including low ECOG performance status, normal haemoglobin, lower T stage and suitability for cisplatin-based chemotherapy were associated with favourable survival in univariate analyses. In addition, low hCGβ level was favourable when assessed either before (median survival not reached vs 1.86 years, P=0.001) or on completion of chemotherapy (4.27 vs 0.42 years, P=0.000002). This was confirmed in multivariate analyses and in patients receiving first- and second-line palliative chemotherapy, and in a radical cystectomy validation set.

Conclusions:

Serum total hCGβ level is an independent prognostic factor in patients receiving chemotherapy for urothelial TCC in both curative and palliative settings.

Use of self-administered instruments to assess psychiatric disorders in older people: validity of the General Health Questionnaire, the Center for Epidemiologic Studies Depression Scale and the self-completion version of the revised Clinical Interview Schedule

BACKGROUND

Diagnosis of depressive disorder using interviewer-administered instruments is expensive and frequently impractical in large epidemiological surveys. The aim of this study was to assess the validity of three self-completion measures of depressive disorder and other psychiatric disorders in older people against an interviewer-administered instrument.

METHOD

A random sample stratified by sex, age and social position was selected from the Whitehall II study participants. This sample was supplemented by inclusion of depressed Whitehall II participants. Depressive disorder and other mental disorders were assessed by the interviewer-administered structured revised Clinical Interview Schedule (CIS-R) in 277 participants aged 58-80 years. Participants also completed a computerized self-completion version of the CIS-R in addition to the General Health Questionnaire (GHQ) and the Center for Epidemiologic Studies Depression Scale (CES-D).

RESULTS

The mean total score was similar for the interviewer-administered (4.43) and self-completion (4.35) versions of the CIS-R [95% confidence interval (CI) for difference -0.31 to 0.16]. Differences were not related to sex, age, social position or presence of chronic physical illness. Sensitivity/specificity of self-completion CIS-R was 74%/98% for any mental disorder and 75%/98% for depressive episode. The corresponding figures were 86%/87% and 78%/83% for GHQ and 77%/89% and 89%/86% for CES-D.

CONCLUSIONS

The self-completion computerized version of the CIS-R is feasible and has good validity as a measure of any mental disorder and depression in people aged ≥ 60 years. GHQ and CES-D also have good criterion validity as measures of any mental disorder and depressive disorder respectively.

Effects of methylmercury on epigenetic markers in three model species: mink, chicken and yellow perch

We previously reported that methylmercury (MeHg) exposure is associated with DNA hypomethylation in the brain stem of male polar bears. Here, we conveniently use archived tissues obtained from controlled laboratory exposure studies to look for evidence that MeHg can disrupt DNA methylation across taxa. Brain (cerebrum) tissues from MeHg-exposed mink (Neovison vison), chicken (Gallus gallus) and yellow perch (Perca flavescens) were analyzed for total Hg levels and global DNA methylation. Tissues from chicken and mink, but not perch, were also analyzed for DNA methyltransferase (DNMT) activity. In mink we observed significant reductions in global DNA methylation in an environmentally-relevant dietary exposure group (1 ppm MeHg), but not in a higher group (2 ppm MeHg). DNMT activity was significantly reduced in all treatment groups. In chicken or yellow perch, no statistically significant effects of MeHg were observed. Dose-dependent trends were observed in the chicken data but the direction of the change was not consistent between the two endpoints. Our results suggest that MeHg can be epigenetically active in that it has the capacity to affect DNA methylation in mammals. The variability in results across species may suggest inter-taxa differences in epigenetic responses to MeHg, or may be related to differences among the exposure scenarios used as animals were exposed to MeHg through different routes (dietary, egg injection), for different periods of time (19-89 days) and at different life stages (embryonic, juvenile, adult).

Maternal separation in childhood and diurnal cortisol patterns in mid-life: findings from the Whitehall II study

BACKGROUND

Animal studies suggest that maternal separation is associated with alterations in the hypothalamic-pituitary-adrenal (HPA) axis through effects that occur in a critical period following birth. Evidence for an association of the diurnal cortisol rhythm with maternal separation in humans is equivocal.

METHOD

We examined whether maternal separation in childhood is associated with diurnal cortisol pattern in 3712 middle-aged men and women. Two aspects of cortisol release were examined: the cortisol awakening response (CAR) and the diurnal slope in cortisol throughout the day.

RESULTS

Maternal separation in childhood was reported by 12% of participants. Those participants who reported maternal separation had a larger CAR and flatter slopes in cortisol levels compared to those who did not report maternal separation [adjusted mean CAR in those reporting no separation versus separation: 7.1, 95% confidence interval (CI) 6.7-7.5 v. 8.4, 95% CI 7.3-9.5, p = 0.02, corresponding to adjusted mean diurnal slope: -0.129 (95% CI -0.130 to -0.128) v. -0.126 (95% CI -0.128 to -0.124), p = 0.01]. In participants who reported maternal separation, the age of separation was not associated with either cortisol measure (p = 0.11). The association between maternal separation and slope in cortisol secretion was largely explained by smoking behaviour and marital status at the time of sample collection whereas that of the CAR was explained by childhood psychosocial, material factors and adult health behaviours.

CONCLUSIONS

Our findings suggest that maternal separation in childhood is associated with alterations in the diurnal cortisol pattern in middle age. These associations are predominantly accounted for by adult circumstances and behaviours.

Socioeconomic position predicts long-term depression trajectory: a 13-year follow-up of the GAZEL cohort study

Individuals with low socioeconomic position have high rates of depression; however, it is not clear whether this reflects higher incidence or longer persistence of disorder. Past research focused on high-risk samples, and risk factors of long-term depression in the population are less well known. Our aim was to test the hypothesis that socioeconomic position predicts depression trajectory over 13 years of follow-up in a community sample. We studied 12 650 individuals participating in the French GAZEL study. Depression was assessed by the Center for Epidemiological Studies-Depression scale in 1996, 1999, 2002, 2005 and 2008. These five assessments served to estimate longitudinal depression trajectories (no depression, decreasing depression, intermediate/increasing depression, persistent depression). Socioeconomic position was measured by occupational grade. Covariates included year of birth, marital status, tobacco smoking, alcohol consumption, body mass index, negative life events and preexisting psychological and non-psychological health problems. Data were analyzed using multinomial regression, separately in men and women. Overall, participants in intermediate and low occupational grades were significantly more likely than those in high grades to have an unfavorable depression trajectory and to experience persistent depression (age-adjusted ORs: respectively 1.40, 95% confidence interval (CI) 1.16-1.70 and 2.65, 95% CI 2.04-3.45 in men, 2.48, 95% CI 1.36-4.54 and 4.53, 95% CI 2.38-8.63 in women). In multivariate models, the socioeconomic gradient in long-term depression decreased by 21-59% in men and women. Long-term depression trajectories appear to follow a socioeconomic gradient; therefore, efforts aiming to reduce the burden of depression should address the needs of the whole population rather than exclusively focus on high-risk groups.

Diagnosis-specific sick leave as a long-term predictor of disability pension: a 13-year follow-up of the GAZEL cohort study

BACKGROUND

Factors that increase the risk of labour market exclusion are poorly understood. In this study, we examined the extent to which all-cause and diagnosis-specific sick leave predict subsequent disability pension (DP).

METHODS

Prospective cohort study of 20 434 persons employed by the French national gas and electric company (the GAZEL study). New sick-leave spells >7 days in 1990-1992 were obtained from company records. Follow-up for DP was from 1994 to 2007.

RESULTS

The HR, adjusted for age and occupational position, for DP was 3.5 (95% CI 2.7 to 4.5) in men and 2.6 (95% CI 1.9 to 3.5) in women with one or more sick-leave spells >7 days compared with those with no sick leave. The strongest predictor of DP was sick leave with a psychiatric diagnosis, HR 7.6 (95% CI 5.2 to 10.9) for men and 4.1 (95% CI 2.9 to 5.9) for women. Corresponding HRs for sick leave due to circulatory diagnoses in men and women were 5.6 (95% CI 3.7 to 8.6) and 3.1 (95% CI 1.8 to 5.3), for respiratory diagnoses 3.9 (95% CI 2.6 to 5.8) and 2.6 (95% CI 1.7 to 4.0), and musculoskeletal diagnoses 4.6 (95% CI 3.4 to 6.4) and 3.3 (95% CI 2.2 to 4.8), respectively.

CONCLUSIONS

Sick leave with a psychiatric diagnosis is a major risk factor for subsequent DP, especially among men. Sick leave due to musculoskeletal or circulatory disorders was also a strong predictor of DP. Diagnosis-specific sick leave should be recognised as an early risk marker for future exclusion from the labour market.

Time trends in childhood and adolescent obesity in England from 1995 to 2007 and projections of prevalence to 2015

BACKGROUND

The aim was to examine the 1995-2007 childhood and adolescent obesity trends and project prevalence to 2015 by age group and social class.

METHODS

Participants were children aged 2-10 and adolescents aged 11-18 years from general population households in England studied using repeated cross-sectional surveys. Obesity was computed using international standards. Prevalence projections to 2015 were based on extrapolation of linear and non-linear trends.

RESULTS

Obesity prevalence increased from 1995 to 2007 from 3.1% to 6.9% among boys, and 5.2% to 7.4% among girls. There are signs of a levelling off trend past 2004/5. Assuming a linear trend, the 2015 projected obesity prevalence is 10.1% (95% CI 7.5 to 12.6) in boys and 8.9% (5.8 to 12.1) in girls, and 8.0% (4.5, 11.5) in male and 9.7% (6.0, 13.3) in female adolescents. Projected prevalence in manual social classes is markedly higher than in non-manual classes [boys: 10.7% (6.6 to 14.9) vs 7.9% (3.7 to 12.1); girls: 11.2% (7.0 to 15.3) vs 5.4% (1.3 to 9.4); male adolescents: 10.0% (5.2 to 14.8) vs 6.7% (3.4 to 10.0); female adolescents: 10.4% (5.0 to 15.8) vs 8.3% (4.3 to 12.4)].

CONCLUSION

If the trends in young obesity continue, the percentage and numbers of obese young people in England will increase considerably by 2015 and the existing obesity gap between manual and non-manual classes will widen further. This highlights the need for public health action to reverse recent trends and narrow social inequalities in health.

Occupation and mental health in a national UK survey

OBJECTIVES

To measure the prevalence of common mental disorder (CMD) by occupation in a representative sample of Great Britain and to identify occupations with increased and decreased risk of CMD.

METHODS

A cross-sectional interview-based survey was carried out including 5,497 working male and female respondents, 16-64 years from a stratified random survey of private households in Britain. Occupations were classified by the Standard Occupational Classification (SOC) into four groups: major, sub-major, minor and constituent unit groups. Common Mental Disorder was measured by the Revised Clinical Interview Schedule.

RESULTS

Major SOC groups with higher prevalence of common mental disorder included clerical and secretarial, sales, and personal and protective services whereas craft and related, 'other' professional occupations and plant and machine operatives had lower prevalence compared to 13% overall prevalence in all adults. In sub-major SOC groups managers and administrators, teaching professionals, clerical and secretarial, 'other' sales and personal service occupations had higher prevalence whereas many professional and skilled occupations had lower prevalence. Specific SOC unit groups with higher prevalence included primary and secondary teachers, welfare community, youth workers, security staff, waiters, bar staff, nurse auxiliaries and care assistants. General managers in government and large organizations (OR=2.79, 95% CI 1.41-5.54), managers in transport and storing (OR=2.44, 95% CI 1.18-5.03), buyers and mobile sales persons (OR=2.48, 95% CI 1.09-5.60), sales occupations (NES) (OR=2.78, 95% CI 1.25-6.19) and clerks (NES) (OR=2.71, 95% CI 1.59-4.61) had increased risk of common mental disorder relative to specialist managers adjusting for social and financial factors and physical ill-health.

CONCLUSIONS

Occupations with higher risk of common mental disorder may be typified by high levels of job demands, especially emotional demands and lack of job security. The reasons why occupations have low rates of common mental disorder are varied and may include high levels of job discretion, good job training and clearly defined job tasks.

Increasing antiviral activity of surfactant protein d trimers by introducing residues from bovine serum collectins: dissociation of mannan-binding and antiviral activity

Collectins contribute to host defence through interactions with glycoconjugates on pathogen surfaces. We have prepared recombinant trimeric neck and carbohydrate recognition domains (NCRD) of collectins, and we now show that the NCRD of bovine conglutinin and CL-46 (like that of CL-43) have greater intrinsic antiviral activity for influenza A virus (IAV) than the human SP-D NCRD (hSP-D-NCRD). The three serum collectins differ from SP-D by having insertions adjacent to amino acid 325 and substitution of hydrophobic residues for arginine 343. We previously showed that a three amino acid (RAK) insertion, as found in CL-43, increases antiviral activity and mannan-binding activity of the hSP-D-NCRD, while the substitution of valine at 343, as in conglutinin, more strongly increased these activities. Mannan-binding activity of collectins has been considered to predict for ability to bind to high mannose glycans on viruses or other pathogens. We now show, however, that combined mutants containing the RAK insertion and R343V or R343I substitutions have greatly increased mannan-binding ability, but lower IAV binding or inhibiting activity than mutants containing R343V or R343I substitutions only. These findings indicate differences in the recognition of glycan structures of mannan and IAV by the NCRD and emphasize the importance of the flanking sequences in determining the differing interactions of human SP-D and bovine serum collectins with mannose-rich glycoconjugates on IAV and other pathogens. Of interest, we show conservation of some monoclonal antibody-binding epitopes between bovine collectin NCRD and hSP-D, suggesting shared structural motifs.

A combination of tigecycline, colistin, and meropenem against multidrug-resistant Acinetobacter baumannii bacteremia in a renal transplant recipient: pharmacodynamic and microbiological aspects

Acinetobacter baumannii are emerging as the causal agents of healthcare-associated infections. We describe arenal transplant recipient who developed bacteremia caused by multiresistant A. baumannii, which received a combination of tigecycline, colistin, and meropenem in continuous infusion. The clinical outcome was favorable. In this article we made a molecular study of this multiresistant strain. Our analysis reveals the presence of abla-OXA-72 gene,a class D of oxacillinase belonging to bla-OXA-40-like group,which constitutes the most disseminated familiy of carbapenemases in Spain. Thus, we found different susceptibility patterns of A. baumannii when we used different Mueller-Hinton agars with different manganese concentrations. Lastly, we explain the combination of these three antibiotics administered to increase microbiologic and pharmacodynamic yield.

The association of cognitive performance with mental health and physical functioning strengthens with age: the Whitehall II cohort study

BACKGROUND

Cognitive performance has been associated with mental and physical health, but it is unknown whether the strength of these associations changes with ageing and with age-related social transitions, such as retirement. We examined whether cognitive performance predicted mental and physical health from midlife to early old age.

METHOD

Participants were 5414 men and 2278 women from the Whitehall II cohort study followed for 15 years between 1991 and 2006. The age range included over the follow-up was from 40 to 75 years. Mental health and physical functioning were measured six times using SF-36 subscales. Cognitive performance was assessed three times using five cognitive tests assessing verbal and numerical reasoning, verbal memory, and phonemic and semantic fluency. Socio-economic status (SES) and retirement were included as covariates.

RESULTS

High cognitive performance was associated with better mental health and physical functioning. Mental health differences associated with cognitive performance widened with age from 39 to 76 years of age, whereas physical functioning differences widened only between 39 and 60 years and not after 60 years of age. SES explained part of the widening differences in mental health and physical functioning before age 60. Cognitive performance was more strongly associated with mental health in retired than non-retired participants, which contributed to the widening differences after 60 years of age.

CONCLUSIONS

The strength of cognitive performance in predicting mental and physical health may increase from midlife to early old age, and these changes may be related to SES and age-related transitions, such as retirement.