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Housing Conditions (housing + condition)
Selected AbstractsAltered motor activity, exploration and anxiety in heterozygous neuregulin 1 mutant mice: implications for understanding schizophreniaGENES, BRAIN AND BEHAVIOR, Issue 7 2007T. Karl Human genetic studies have shown that neuregulin 1 (NRG1) is a potential susceptibility gene for schizophrenia. Nrg1 influences various neurodevelopmental processes, which are potentially related to schizophrenia. The neurodevelopmental theory of schizophrenia suggests that interactions between genetic and environmental factors are responsible for biochemical alterations leading to schizophrenia. To investigate these interactions and to match experimental design with the pathophysiology of schizophrenia, we applied a comprehensive behavioural phenotyping strategy for motor activity, exploration and anxiety in a heterozygous Nrg1 transmembrane domain mutant mouse model (Nrg1 HET) using different housing conditions and age groups. We observed a locomotion- and exploration-related hyperactive phenotype in Nrg1 HETs. Increased age had a locomotion- and exploration-inhibiting effect, which was significantly attenuated in mutant mice. Environmental enrichment (EE) had a stimulating influence on locomotion and exploration. The impact of EE was more pronounced in Nrg1 hypomorphs. Our study also showed a moderate task-specific anxiolytic-like phenotype for Nrg1 HETs, which was influenced by external factors. The behavioural phenotype detected in heterozygous Nrg1 mutant mice is not specific to schizophrenia per se, but the increased sensitivity of mutant mice to exogenous factors is consistent with the pathophysiology of schizophrenia and the neurodevelopmental theory. Our findings reinforce the importance of carefully controlling experimental designs for external factors and of comprehensive, integrative phenotyping strategies. Thus, Nrg1 HETs may, in combination with other genetic and drug models, help to clarify pathophysiological mechanisms behind schizophrenia. [source] Age effects on the regulation of adult hippocampal neurogenesis by physical activity and environmental enrichment in the APP23 mouse model of Alzheimer diseaseHIPPOCAMPUS, Issue 10 2009Sebastian Mirochnic Abstract An active lifestyle is to some degree protective against Alzheimer's disease (AD), but the biological basis for this benefit is still far from clear. We hypothesize that physical and cognitive activity increase a reserve for plasticity by increasing adult neurogenesis in the hippocampal dentate gyrus (DG). We thus assessed how age affects the response to activity in the murine APP23 model of AD compared with wild type (WT) controls and studied the effects of physical exercise (RUN) and environmental enrichment (ENR) in comparison with standard housing (CTR) at two different ages (6 months and 18 months) and in both genotypes. At 18 months, both activity paradigms reduced the hippocampal human A,1-42/A,1-40 ratio when compared with CTR, despite a stable plaque load in the hippocampus. At this age, both RUN and ENR increased the number of newborn granule cells in the DG of APP23 mice when compared with CTR, whereas the levels of regulation were equivalent to those in WT mice under the same housing conditions. At 6 months, however, neurogenesis in ENR but not RUN mice responded like the WT. Quantifying the number of cells at the doublecortin-positive stage in relation to the number of cells on postmitotic stages we found that ENR overproportionally increased the number of the DCX-positive "late" progenitor cells, indicative of an increased potential to recruit even more new neurons. In summary, the biological substrates for activity-dependent regulation of adult hippocampal neurogenesis were preserved in the APP23 mice. We thus propose that in this model, ENR even more than RUN might contribute to a "neurogenic reserve" despite a stable plaque load and that age affects the outcome of an interaction based on "activity." © 2009 Wiley-Liss, Inc. [source] Energy metabolism in young pigs as affected by establishment of new groups prior to transportJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2002M. J. W. HEETKAMP Energy metabolism was studied in 9-week-old-pigs as affected by mixing just before transport. In each of three trials, two groups of 20 pigs (two litters of 10) were randomly assigned to one of two treatments: control and mixing. Each group was housed in one of two climatic chambers with each subgroup in one of two pens. In each trial, the two litters within the mixing treatment were mixed, just before transport, at the start of a 2-week experimental period. In the control treatment, the social structure of both litters in each trial was not altered. In both treatments, large alterations of energy partitioning from week 1 to week 2, are probably signs of recovering from transportation and/or adaptation to new feeding and housing conditions. Mixing just before transport did not change total energy metabolism but only increased nonactivity-related heat production by 3.1% for the total experimental period. Most likely, long-term performance is also not affected negatively by mixing. Animals seem to be able to change energy expenditure on activity when more energy is required for other physiological processes. This symptom of possible reallocation of energy between different vital live processes (e.g. behavior, protein turn-over) might be one of the first indications of an impaired well-being. [source] Coat condition, housing condition and measurement of faecal cortisol metabolites , a non-invasive study about alopecia in captive rhesus macaques (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2006Hanspeter W. Steinmetz Abstract Background, Previous studies have characterized alopecia in captive rhesus macaques (Macaca mulatta) by a mixed partial to complete alopecia in a bilateral symmetric pattern. Methods, In this study, coat condition assessments were related to exogenous and endogenous factors in captive rhesus macaques under different housing conditions in order to identify disturbances in environmental factors controlling or influencing hair growth. Additionally, the degree of alopecia was investigated in relation to adrenal endocrine function as an indicator of social stress using faecal glucocorticoid measurements. Results, Hair loss was found to vary with season and sex, was most pronounced in adult females during the winter and spring months. Generally, infants were not affected, but alopecia developed during adolescence. However, the housing system, available enclosure space and variations in group size and composition also appeared to influence coat condition. Levels of immunoreactive cortisol metabolites (11-oxoetiocholanolone) in faeces were significantly negatively correlated with alopecia, suggesting a relationship between hypothalamic-pituitary-adrenal (HPA) axis activity and hair loss in captive rhesus macaques. Conclusions, Although the present study demonstrates the influence of the HPA axis on coat condition, it is not known if hair loss is caused by abnormal behaviour or hormonal imbalances of the HPA axis itself. Our data suggest that alopecia in rhesus macaques is a highly complex multicausal disorder. [source] THE GEOGRAPHY OF INSECURITY: SPATIAL CHANGE AND THE FLEXIBILIZATION OF LABOR IN METRO MANILAJOURNAL OF URBAN AFFAIRS, Issue 4 2009GAVIN SHATKIN ABSTRACT:,There has been considerable attention in the urban studies literature to the implications of spatial change associated with globalization for the urban poor in advanced economies, but much less so in developing countries despite the fact that this is where most urbanization is occurring. This article attempts to address this issue in the context of Metro Manila, a globalizing city of 10.7 million that sits in a larger mega-urban region of some 17 million. It does so through an analysis of data collected through two methods: a sample survey of six low-income settlements in the Metro Manila region that collected information about housing conditions, income, and employment of household members, commuting, and household heads',opinions regarding spatial change; and in-depth interviews with a subset of respondents that were intended to generate narratives and stories that would elucidate the experience of households with spatial change. The study identifies three main issues confronting the surveyed households: the social impacts of the flexibilization of labor in the Metro Manila region, gender and age differences in access to employment, and the prevalence of extremely long commutes on the urban fringe. The article concludes that the issues faced by Metro Manila households are in many ways quite distinct from those in cities in advanced economies. It further argues that these differences have important implications both for urban policy and practice in addressing equity issues, and for theories of globalization and issues of spatial change and social equity in cities. [source] Conduct problems, IQ, and household chaos: a longitudinal multi-informant studyTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 10 2009Kirby Deater-Deckard Background:, We tested the hypothesis that household chaos would be associated with lower child IQ and more child conduct problems concurrently and longitudinally over two years while controlling for housing conditions, parent education/IQ, literacy environment, parental warmth/negativity, and stressful events. Methods:, The sample included 302 families with same-sex twins (58% female) in Kindergarten/1st grade at the first assessment. Parents' and observers' ratings were gathered, with some collected over a two-year period. Results:, Chaos varied widely. There was substantial mother,father agreement and longitudinal stability. Chaos covaried with poorer housing conditions, lower parental education/IQ, poorer home literacy environment, higher stress, higher negativity and lower warmth. Chaos statistically predicted lower IQ and more conduct problems, beyond the effects of other home environment factors. Conclusions:, Even with other home environment factors controlled, higher levels of chaos were linked concurrently with lower child IQ, and concurrently and longitudinally with more child conduct problems. Parent self-reported chaos represents an important aspect of housing and family functioning, with respect to children's cognitive and behavioral functioning. [source] Infants with HIV-infected mothers in a universal newborn hearing screening programme in Lagos, NigeriaACTA PAEDIATRICA, Issue 8 2009Bolajoko O Olusanya Abstract Aim:, To establish the characteristics of infants with human immunodeficiency virus (HIV)-infected mothers enrolled under a two-stage universal newborn hearing screening programme in Lagos, Nigeria. Methods:, A matched case-control study from May 2005 to December 2007 in which factors associated with maternal HIV status were determined by conditional multivariable logistic regression analysis. Results:, Some 266 newborns had HIV-infected mothers and were matched with 1330 controls by age and sex. Factors independently associated with increased risk of maternal HIV status were ethnicity, religion, housing sanitation facilities and prematurity while prior or current caesarean section, admission into special care unit and hyperbilirubinaemia were associated with lower risk of maternal HIV. Maternal HIV status was not significantly associated (p = 0.082) with the risk of sensorineural hearing loss although newborns with HIV-infected mothers had more than two-fold risk (p = 0.030) of not completing the hearing tests compared with controls. Conclusion:, HIV-infected mothers are likely to live in poor housing conditions but their newborns are not at an increased risk of sensorineural hearing loss in this setting barring the potential effect of significantly increased drop-out rate in this group. [source] | |||||||||||||