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91.

Background

Individuals with a history of suicide attempt have a high risk for subsequent labour market marginalization. This study aimed at assessing the effect of individual and parental factors on different measures of marginalization.

Methods

Prospective cohort study based on register linkage of 5 649 individuals who in 1994 were 16–30 years old, lived in Sweden and were treated in inpatient care for suicide attempt during 1992–1994. Hazard ratios (HRs) for labour market marginalization defined as long-term unemployment (>180 days), sickness absence (>90 days), or disability pension in 1995–2010 were calculated with Cox regression.

Results

Medical risk factors, particularly any earlier diagnosed specific mental disorders (e.g., schizophrenia: HR 5.4 (95% CI: 4.2, 7.0), personality disorders: HR 3.9, 95% CI: 3.1, 4.9), repetitive suicide attempts (HR 1.6, 95% CI: 1.4, 1.9) were associated with a higher relative risk of disability pension. Individual medical factors were of smaller importance for long-term sickness absence, and of only marginal relevance to long-term unemployment. Country of birth outside Europe had an opposite effect on disability pension (HR 0.6, 95% CI: 0.4, 0.8) and long-term unemployment (HR 1.5, 95% CI: 1.3, 1.8). Female sex was positively correlated with long-term sickness absence (HR 1.6, 95% CI: 1.4, 1.7), and negatively associated with long-term unemployment (HR: 0.8, 95% CI: 0.7, 0.9).

Conclusions

As compared to disability pension, long-term sickness absence and unemployment was more strongly related to socio-economic variables. Marginalization pathways seemed to vary with migration status and sex. These findings may contribute to the development of intervention strategies which take the individual risk for marginalization into account.  相似文献   
92.
Capsule: Apparent adult survival of the critically endangered Baltic Dunlin Calidris alpina schinzii, showed evidence of a decline between 1990 and 2006 from 0.817 to 0.650.

Aims: In Europe, declines in wet-grassland breeding waders have been attributed to changes in breeding habitat but long-term information on survival is rare. We examined whether adult survival of the Baltic Dunlin declined during a period of strong population decline.

Methods: We modelled apparent survival using Cormack–Jolly–Seber models and long-term capture–recapture data collected from a Danish population. We fitted models that constrained apparent adult survival with linear and quadratic trends, and compared them with constant and time dependent models to test whether survival declined during the study period.

Results: Models including linear and quadratic trends were most supported. However, the trend variables explained only 24–35% of observed temporal variance suggesting that a large portion of variation in survival remained undescribed. Model averaged estimates indicated a decline in adult survival from 0.817 to 0.650 between 1990 and 2006 with increased uncertainty towards the end.

Conclusion: Our results suggest that gradual long-term changes in adult survival may have contributed to the decline of the Baltic Dunlin.  相似文献   

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Divergent natural selection regimes can contribute to adaptive population divergence, but can be sensitive to human‐mediated environmental change. Nutrient loading of aquatic ecosystems, for example, might modify selection pressures by altering the abundance and distribution of resources and the prevalence and infectivity of parasites. Here, we used a mesocosm experiment to test for interactive effects of nutrient loading and parasitism on host condition and feeding ecology. Specifically, we investigated whether the common fish parasite Gyrodactylus sp. differentially affected recently diverged lake and stream ecotypes of three‐spined stickleback (Gasterosteus aculeatus). We found that the stream ecotype had a higher resistance to Gyrodactylus sp. infections than the lake ecotype, and that both ecotypes experienced a cost of parasitism, indicated by negative relationships between parasite load and both stomach fullness and body condition. Overall, our results suggest that in the early stages of adaptive population divergence of hosts, parasites can affect host resistance, body condition and diet.  相似文献   
96.
Coagulation factor VIIa (FVIIa) belongs to a family of proteases being part of the stepwise, self-amplifying blood coagulation cascade. To investigate the impact of the mutation Met(298{156})Lys in FVIIa, we replaced the Gly(283{140})-Met(298{156}) loop with the corresponding loop of factor Xa. The resulting variant exhibited increased intrinsic activity, concurrent with maturation of the active site, a less accessible N-terminus, and, interestingly, an altered macromolecular substrate specificity reflected in an increased ability to cleave factor IX (FIX) and a decreased rate of FX activation compared to that of wild-type FVIIa. In complex with tissue factor, activation of FIX, but not of FX, returned to normal. Deconvolution of the loop graft in order to identify important side chain substitutions resulted in the mutant Val(158{21})Asp/Leu(287{144})Thr/Ala(294{152})Ser/Glu(296{154}) Ile/Met(298{156})Lys-FVIIa with almost the same activity and specificity profile. We conclude that a lysine residue in position 298{156} of FVIIa requires a hydrophilic environment to be fully accommodated. This position appears critical for substrate specificity among the proteases of the blood coagulation cascade due to its prominent position in the macromolecular exosite and possibly via its interaction with the corresponding position in the substrate (i.e. FIX or FX).  相似文献   
97.
Dopamine D1 receptors play an important role in movement, reward, and learning and are implicated in a number of neurological and psychiatric disorders. These receptors are concentrated in dendritic spines of neurons, including the spine head and the postsynaptic density. D1 within spines is thought to modulate the local channels and receptors to control the excitability and synaptic properties of spines. The molecular mechanisms mediating D1 trafficking, anchorage, and function in spines remain elusive. Here we show that the synaptic scaffolding protein PSD-95 thought to play a role in stabilizing glutamate receptors in the postsynaptic density, interacts with D1 and regulates its trafficking and function. Interestingly, the D1-PSD-95 interaction does not require the well characterized domains of PSD-95 but is mediated by the carboxyl-terminal tail of D1 and the NH(2) terminus of PSD-95, a region that is recognized only recently to participate in protein-protein interaction. Co-expression of PSD-95 with D1 in mammalian cells inhibits the D1-mediated cAMP accumulation without altering the total expression level or the agonist binding properties of the receptor. The diminished D1 signaling is mediated by reduced D1 expression at the cell surface as a consequence of an enhanced constitutive, dynamin-dependent endocytosis. In addition, genetically engineered mice lacking PSD-95 show a heightened behavioral response to either a D1 agonist or the psychostimulant amphetamine. These studies demonstrate a role for a glutamatergic scaffold in dopamine receptor signaling and trafficking and identify a new potential target for the modulation of abnormal dopaminergic function.  相似文献   
98.
The early transition of knowledge from highly specialised and sophisticated proteomics research to a diverse community in need of know-how is a challenge that requires backing from advanced research centres and groups, and a coordinating body for the dissemination of this knowledge. The European Proteomics Association (EuPA) Education Committee signified this as a priority area when the EuPA was formed, and began its program to coordinate proteomics training and knowledge dissemination in 2006. This report serves as an update of our past activities and an announcement of upcoming events. Over the last year the EuPA Education Committee has coordinated or supported different educational activities including basic and advanced courses, a summer school, workshops and tutorials. A new programme of basic courses dubbed "Teaching the Teachers" has been initiated. These courses reach a larger, Europe wide, audience in a short timeframe, thus improving the opportunities for trainees of elementary proteomics techniques. Another important event has been the merger of the EuPA and HUPO (Human Proteome Organisation) Education Committees into a single one in order to combine ideas and ef for ts that will favour global education in proteomics.  相似文献   
99.
Gene duplication with subsequent interaction divergence is one of the primary driving forces in the evolution of genetic systems. Yet little is known about the precise mechanisms and the role of duplication divergence in the evolution of protein networks from the prokaryote and eukaryote domains. We developed a novel, model-based approach for Bayesian inference on biological network data that centres on approximate Bayesian computation, or likelihood-free inference. Instead of computing the intractable likelihood of the protein network topology, our method summarizes key features of the network and, based on these, uses a MCMC algorithm to approximate the posterior distribution of the model parameters. This allowed us to reliably fit a flexible mixture model that captures hallmarks of evolution by gene duplication and subfunctionalization to protein interaction network data of Helicobacter pylori and Plasmodium falciparum. The 80% credible intervals for the duplication–divergence component are [0.64, 0.98] for H. pylori and [0.87, 0.99] for P. falciparum. The remaining parameter estimates are not inconsistent with sequence data. An extensive sensitivity analysis showed that incompleteness of PIN data does not largely affect the analysis of models of protein network evolution, and that the degree sequence alone barely captures the evolutionary footprints of protein networks relative to other statistics. Our likelihood-free inference approach enables a fully Bayesian analysis of a complex and highly stochastic system that is otherwise intractable at present. Modelling the evolutionary history of PIN data, it transpires that only the simultaneous analysis of several global aspects of protein networks enables credible and consistent inference to be made from available datasets. Our results indicate that gene duplication has played a larger part in the network evolution of the eukaryote than in the prokaryote, and suggests that single gene duplications with immediate divergence alone may explain more than 60% of biological network data in both domains.  相似文献   
100.
The genealogical relationship of human, chimpanzee, and gorilla varies along the genome. We develop a hidden Markov model (HMM) that incorporates this variation and relate the model parameters to population genetics quantities such as speciation times and ancestral population sizes. Our HMM is an analytically tractable approximation to the coalescent process with recombination, and in simulations we see no apparent bias in the HMM estimates. We apply the HMM to four autosomal contiguous human–chimp–gorilla–orangutan alignments comprising a total of 1.9 million base pairs. We find a very recent speciation time of human–chimp (4.1 ± 0.4 million years), and fairly large ancestral effective population sizes (65,000 ± 30,000 for the human–chimp ancestor and 45,000 ± 10,000 for the human–chimp–gorilla ancestor). Furthermore, around 50% of the human genome coalesces with chimpanzee after speciation with gorilla. We also consider 250,000 base pairs of X-chromosome alignments and find an effective population size much smaller than 75% of the autosomal effective population sizes. Finally, we find that the rate of transitions between different genealogies correlates well with the region-wide present-day human recombination rate, but does not correlate with the fine-scale recombination rates and recombination hot spots, suggesting that the latter are evolutionarily transient.  相似文献   
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