61 research outputs found
Intergenerational Transfers of Infant Mortality in 19th-Century Northern Sweden
This contribution is part of an international comparative initiative with the aim to assess the analytical power of the Intermediate Data Structure (IDS) in a study of possible intergenerational transmissions of death in infancy. An evaluation of the data in applied research will be useful for further development of the IDS structure and for its future use in comparative research. An additional methodological aim for this part of the study is to evaluate and compare different models for statistical analysis of intergenerational transfers. The analysis is based on a cohort of mothers born 1826-1854, whose experiences of infant mortality are compared to the ones of the previous generation, the grandmothers. Data are collected from Swedish parish records, available in the database POPUM at the Demographic Data Base in UmeÄ. The analysis shows a clear association between infant mortality among mothers and grandmothers. The probability of an infant death for a woman is increased if her mother also had experienced an infant death. Having tested for different approaches of analysis, we found that simple models with few restrictive assumptions gave similar results as more complicated models. Since it is easy to feel confident in the models with the weakest assumptions, we argue that such models are preferred for this type of analysis
Cerebrospinal fluid kynurenine and kynurenic acid concentrations are associated with coma duration and long-term neurocognitive impairment in Ugandan children with cerebral malaria
Background: One-fourth of children with cerebral malaria (CM) retain cognitive sequelae up to 2 years after acute disease. The kynurenine pathway of the brain, forming neuroactive metabolites, e.g. the NMDA-receptor antagonist kynurenic acid (KYNA), has been implicated in long-term cognitive dysfunction in other CNS infections. In the present study, the association between the kynurenine pathway and neurologic/cognitive complications in children with CM was investigated.
Methods: Cerebrospinal fuid (CSF) concentrations of KYNA and its precursor kynurenine in 69 Ugandan children admitted for CM to Mulago Hospital, Kampala, Uganda, between 2008 and 2013 were assessed. CSF kynurenine and KYNA were compared to CSF cytokine levels, acute and long-term neurologic complications, and long-term cogniâ tive impairments. CSF kynurenine and KYNA from eight Swedish children without neurological or infectious disease admitted to Astrid Lindgrenâs Childrenâs Hospital were quantifed and used for comparison.
Results: Children with CM had signifcantly higher CSF concentration of kynurenine and KYNA than Swedish children (P \u3c 0.0001 for both), and CSF kynurenine and KYNA were positively correlated. In children with CM, CSF kynurenine and KYNA concentrations were associated with coma duration in children of all ages (P = 0.003 and 0.04, respecâ tively), and CSF kynurenine concentrations were associated with worse overall cognition (P = 0.056) and attention (P = 0.003) at 12-month follow-up in children â„5 years old.
Conclusions: CSF KYNA and kynurenine are elevated in children with CM, indicating an inhibition of glutamatergic and cholinergic signaling. This inhibition may lead acutely to prolonged coma and long-term to impairment of attenâ tion and cognition
AHAA- Agile, Hybrid Assessment Method for Automotive, Safety Critical SMEs
The need for software is increasingly growing in the automotive industry. Software development projects are, however, often troubled by time and budget overruns, resulting in systems that do not fulfill customer requirements. Both research and industry lack strategies to combine reducing the long software development lifecycles (as required by time-to-market demands) with increasing the quality of the software developed. Software process improvement (SPI) provides the first step in the move towards software quality, and assessments are a vital part of this process. Unfortunately, software process assessments are often expensive and time consuming. Additionally, they often provide companies with a long list of issues without providing realistic suggestions. The goal of this paper is to describe a new low-overhead assessment method that has been designed specifically for small-to-medium-sized (SMEs) organisations wishing to be automotive software suppliers. This assessment method integrates the structured-ness of the plan-driven SPI models of Capability Maturity Model Integration (CMMI) and Automotive SPICETM with the flexibleness of agile practices
Effects of pro-inflammatory cytokines on expression of kynurenine pathway enzymes in human dermal fibroblasts
<p>Abstract</p> <p>Background</p> <p>The kynurenine pathway (KP) is the main route of tryptophan degradation in the human body and generates several neuroactive and immunomodulatory metabolites. Altered levels of KP-metabolites have been observed in neuropsychiatric and neurodegenerative disorders as well as in patients with affective disorders. The purpose of the present study was to investigate if skin derived human fibroblasts are useful for studies of expression of enzymes in the KP.</p> <p>Methods</p> <p>Fibroblast cultures were established from cutaneous biopsies taken from the arm of consenting volunteers. Such cultures were subsequently treated with interferon (IFN)-γ 200 U/ml and/or tumor necrosis factor (TNF)-α, 100 U/ml for 48 hours in serum-free medium. Levels of transcripts encoding different enzymes were determined by real-time PCR and levels of kynurenic acid (KYNA) were determined by HPLC.</p> <p>Results</p> <p>At base-line all cultures harbored detectable levels of transcripts encoding KP enzymes, albeit with considerable variation across individuals. Following cytokine treatment, considerable changes in many of the transcripts investigated were observed. For example, increases in the abundance of transcripts encoding indoleamine 2,3-dioxygenase, kynureninase or 3-hydroxyanthranilic acid oxygenase and decreases in the levels of transcripts encoding tryptophan 2,3-dioxygenase, kynurenine aminotransferases or quinolinic acid phosphoribosyltransferase were observed following IFN-γ and TNF-α treatment. Finally, the fibroblast cultures released detectable levels of KYNA in the cell culture medium at base-line conditions, which were increased after IFN-γ, but not TNF-α, treatments.</p> <p>Conclusions</p> <p>All of the investigated genes encoding KP enzymes were expressed in human fibroblasts. Expression of many of these appeared to be regulated in response to cytokine treatment as previously reported for other cell types. Fibroblast cultures, thus, appear to be useful for studies of disease-related abnormalities in the kynurenine pathway of tryptophan degradation.</p
Elevated glutamine/glutamate ratio in cerebrospinal fluid of first episode and drug naive schizophrenic patients
BACKGROUND: Recent magnetic resonance spectroscopy (MRS) studies report that glutamine is altered in the brains of schizophrenic patients. There were also conflicting findings on glutamate in cerebrospinal fluid (CSF) of schizophrenic patients, and absent for glutamine. This study aims to clarify the question of glutamine and glutamate in CSF of first episode and drug naive schizophrenic patients. METHOD: Levels of glutamine and glutamate in CSF of 25 first episode and drug-naive male schizophrenic patients and 17 age-matched male healthy controls were measured by a high performance liquid chromatography. RESULTS: The ratio (126.1 (median), 117.7 ± 27.4 (mean ± S.D.)) of glutamine to glutamate in the CSF of patients was significantly (z = -3.29, p = 0.001) higher than that (81.01 (median), 89.1 ± 22.5 (mean ± S.D.)) of normal controls although each level of glutamine and glutamate in patients was not different from that of normal controls. CONCLUSION: Our data suggests that a disfunction in glutamate-glutamine cycle in the brain may play a role in the pathophysiology of schizophrenia
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Reply to: New Meta- and Mega-analyses of Magnetic Resonance Imaging Findings in Schizophrenia: Do They Really Increase Our Knowledge About the Nature of the Disease Process?
This work was supported by National Institute of Biomedical Imaging and Bioengineering Grant No. U54EB020403 (to the ENIGMA consortium)
Elevated endogenous GDNF induces altered dopamine signalling in mice and correlates with clinical severity in schizophrenia
Presynaptic increase in striatal dopamine is the primary dopaminergic abnormality in schizophrenia, but the underlying mechanisms are not understood. Here, we hypothesized that increased expression of endogenous GDNF could induce dopaminergic abnormalities that resemble those seen in schizophrenia. To test the impact of GDNF elevation, without inducing adverse effects caused by ectopic overexpression, we developed a novel in vivo approach to conditionally increase endogenous GDNF expression. We found that a 2-3-fold increase in endogenous GDNF in the brain was sufficient to induce molecular, cellular, and functional changes in dopamine signalling in the striatum and prefrontal cortex, including increased striatal presynaptic dopamine levels and reduction of dopamine in prefrontal cortex. Mechanistically, we identified adenosine A2a receptor (A(2A)R), a G-protein coupled receptor that modulates dopaminergic signalling, as a possible mediator of GDNF-driven dopaminergic abnormalities. We further showed that pharmacological inhibition of A(2A)R with istradefylline partially normalised striatal GDNF and striatal and cortical dopamine levels in mice. Lastly, we found that GDNF levels are increased in the cerebrospinal fluid of first episode psychosis patients, and in post-mortem striatum of schizophrenia patients. Our results reveal a possible contributor for increased striatal dopamine signalling in a subgroup of schizophrenia patients and suggest that GDNF-A(2A)R crosstalk may regulate dopamine function in a therapeutically targetable manner.</p
Cortical brain abnormalities in 4474 individuals with schizophrenia and 5098 control subjects via the enhancing neuro Imaging genetics through meta analysis (ENIGMA) Consortium
BACKGROUND: The profile of cortical neuroanatomical abnormalities in schizophrenia is not fully understood, despite hundreds of published structural brain imaging studies. This study presents the first meta-analysis of cortical thickness and surface area abnormalities in schizophrenia conducted by the ENIGMA (Enhancing Neuro Imaging Genetics through Meta Analysis) Schizophrenia Working Group.
METHODS: The study included data from 4474 individuals with schizophrenia (mean age, 32.3 years; range, 11-78 years; 66% male) and 5098 healthy volunteers (mean age, 32.8 years; range, 10-87 years; 53% male) assessed with standardized methods at 39 centers worldwide.
RESULTS: Compared with healthy volunteers, individuals with schizophrenia have widespread thinner cortex (left/right hemisphere: Cohen's d = -0.530/-0.516) and smaller surface area (left/right hemisphere: Cohen's d = -0.251/-0.254), with the largest effect sizes for both in frontal and temporal lobe regions. Regional group differences in cortical thickness remained significant when statistically controlling for global cortical thickness, suggesting regional specificity. In contrast, effects for cortical surface area appear global. Case-control, negative, cortical thickness effect sizes were two to three times larger in individuals receiving antipsychotic medication relative to unmedicated individuals. Negative correlations between age and bilateral temporal pole thickness were stronger in individuals with schizophrenia than in healthy volunteers. Regional cortical thickness showed significant negative correlations with normalized medication dose, symptom severity, and duration of illness and positive correlations with age at onset.
CONCLUSIONS: The findings indicate that the ENIGMA meta-analysis approach can achieve robust findings in clinical neuroscience studies; also, medication effects should be taken into account in future genetic association studies of cortical thickness in schizophrenia
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