WNK1 is an assembly factor for the human ER membrane protein complex

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Morningness–eveningness interferes with perceived health,physical activity,diet and stress levels in working women: A cross-sectional study

Sleep and health are closely interrelated and sleep quality is a well-known contributor to perceived health. However, effects of sleep-timing preference i.e. morningness–eveningness on health has yet to be revealed. In this study, we explored the relationship between morningness–eveningness and perceived health in a sample of female working professionals (N?=?202). Sleep-timing preference was measured using the Composite Scale of Morningness. Perceived health was characterized by Center for Epidemiologic Studies Depression Scale, WHO Well-Being Scale-5 and Patient Health Questionnaire-15 scores. We also investigated possible mechanisms, including stress and health-impairing behaviours. In accordance with previous data, we found more depressive mood, lower well-being and poorer perceived health among evening types. To assess health-impairing behaviours we collected data on smoking habits, alcohol consumption, physical activity and diet. Among the possible mechanism variables, greater stress, less frequent physical activity and less healthy diet were associated with eveningness. Furthermore, stress diminished the strength of the association between morningness–eveningness and depressed mood. Physical activity attenuated the strength of the association between morningness–eveningness and well-being. No effects of alcohol consumption could be identified. Our data show that evening preference behaves as a health risk in terms of associating with poor perceived health. Our findings also suggest that this effect might be mediated by health behaviours and stress.     

Physiological mechanism governing slow and fast development in predatory ladybirds

Aphidophagous and coccidophagous ladybirds, similar to their prey, show marked differences in their pace of life (Dixon, 2000), in particular in their rate of development, with all stages of aphidophagous species developing much faster than those of coccidophagous species. Two hypotheses are proposed to account for the large difference in the pace of life of these two groups. These are that differences in the rate of development are a result of differences in lower temperature thresholds for development or the quality of their respective prey as food (Dixon et al., 2011). Analysis of published results on the rates of development of the eggs of ladybirds indicates that the inverse relationships between the number of day‐degrees required for development (K) and the lower temperature threshold for development (td_min) of these two groups are significantly different. In particular, the respective td_min overlap and K of the aphidophagous and coccidophagous species with a similar td_min are, on average, 38 and 117 day‐degrees (D^o). The relationship between the rate of development (R) and temperature (T) for aphids reared on poor‐ or high‐quality foods indicates that, although the value of td_min of a species depends on food quality, K does not, showing that it is unlikely that K is governed by food quality. Thus, there is little support for differences in either the td_min or food quality governing the difference in the pace of life of these two groups of ladybirds. The results indicate that the physiological mechanism that may govern the difference in the pace of life between these two groups is the number of day‐degrees (K) needed to complete their development. The possible evolutionary reason for this is discussed.     

Twelve-Hour Night Shifts of Healthcare Workers: A Risk to the Patients?

We assessed the impact of 12h fixed night shift (19:00–07:00h) work, followed by 36h of off-time, on the sleep–wake cycle, sleep duration, self-perceived sleep quality, and work-time alertness on a group composed of 5 registered and 15 practical nurses. Wrist actigraphy (Ambulatory Monitoring, Inc.), with data analysis by the Cole-Kripke algorithm, was applied to determine sleep/wake episodes and their duration. The sleep episodes were divided into six categories: sleep during the night shift (x¯=208.6; SD±90.6mins), sleep after the night shift (x¯=138.7; SD±79.6min), sleep during the first night after the night work (x¯=318.5; SD±134.6min), sleep before the night work (x¯=104.3; SD±44.1min), diurnal sleep during the rest day (x¯=70.5; SD±43.0min), and nocturnal sleep during the rest day (x¯=310.4; SD±188.9mins). A significant difference (p<.0001; T-test for dependent samples) was detected between the perceived quality of sleep of the three diurnal sleep categories compared to the three nocturnal sleep categories. Even thought the nurses slept (napped) during the night shift, their self-perceived alertness systematically decreased during it. Statistically significant differences were documented by one-way ANOVA (F=40.534 p<.0001) among the alertness measurements done during the night shift. In particular, there was significant difference in the level of perceived alertness (p<.0001) between the 7^th and 10^thh of the 12h night shift. These findings of decreased alertness during the terminal hours of the night shift are of concern, since they suggest risk of comprised patient care.     

News from the Biological Stain Commission No. 12

Abstract

In this 12^th issue of News from the Biological Stain Commission (BSC) under the heading of Regulatory affairs, the Biological Stain Commission’s International Affairs Committee presents information from the meetings of ISO/TC 212/WG 1 Quality and competence in the medical laboratory and ISO/TC 212/WG 3 In vitro diagnostic products both held on 2 – 3 June 2010, plus information on the second plenary meeting of ISO/TC 212 Clinical laboratory testing and in vitro diagnostic test systems held on 4 June 2010. All meetings took place in Seoul, Republic of Korea. Finally, information is provided concerning the 25^th meeting of CEN/TC 140 In vitro diagnostic medical devices held on 23 June 2010 in Berlin, Germany.     

Lifestyle factors and sperm aneuploidy

Different environmental and lifestyle factors may interfere with the normal disjunction of sister chromatids/chromosomes during meiosis and may cause aneuploidy. The aim of the study was to examine the association between lifestyle factors and sperm aneuploidy. The study population consisted of 212 healthy men under 45 years of age attending an infertility clinic for diagnostic purposes and who had a normal semen concentration of 20–300 × 10⁶ mL or slight oligozoospermia (semen concentration of 15–20 × 10⁶/mL). All participants were interviewed and provided a semen sample. Sperm aneuploidy was assessed using multicolor FISH (DNA probes specific for chromosomes X, Y, 18, 13, 21). Results from the study suggest that lifestyle factors are related to sperm aneuploidy. A positive relationship was found between coffee drinking everyday and the lack of chromosome X or Y, as well as coffee drinking 1–6 times per week and additional chromosome 18. Wearing boxer shorts decrease the copy number changes in the whole chromosome 18, the number of additional chromosome 18 and the lack of chromosome 13. Additionally, obesity (BMI 30–40 kg/m²) was positively associated with additional chromosome 21 after being adjusted for potential confounders. These findings demonstrate that changing the men's lifestyle habits may contribute to reduction of the incidence of sperm aneuploidy. It is necessary that men continue to follow sensible health advice concerning excess weight, coffee drinking and wearing tight fitting underwear. As this is the first such study to examine different lifestyle factors and sperm aneuploidy, the results need to be confirmed on larger population.     

Catchment context and the bottom‐up regulation of the abundance of specialist semi‐aquatic weevils on water hyacinth

1. Bottom‐up regulation is prevalent in plant–herbivore interactions and is thought to be particularly important in the case of aquatic plants and their specialist insect herbivores. 2. Recently published mesocosm studies have shown that the abundance of specialist Neochetina weevils, N. bruchi and N. eichhorniae, on water hyacinth (Eichhornia crassipes) are principally under the influence of nutrients in plant tissues. 3. We examined historical patterns of the abundance of these species of semi‐aquatic weevils in two water bodies from catchments with significantly different nutrient loads in subtropical Australia to test the validity of the published conceptual model of bottom‐up regulation. 4. Our results revealed that these weevils are indeed under bottom‐up regulation under field conditions. However, the nature of this regulation appears to be influenced by the broader catchment context of the water hyacinth‐infested water body, with plant tissue nutrients influencing weevil abundance more in the catchment with lower nutrient run‐offs. 5. Our findings reaffirm the importance of bottom‐up regulation in plant–insect interactions, add to the growing evidence of indirect effects spanning terrestrial and aquatic ecosystems, and inform management of water hyacinth using these weevils as biocontrol agents.     

Toxicity and deleterious impacts of selenium nanoparticles at supranutritional and imbalance levels on male goldfish (Carassius auratus) sperm

BackgroundSelenium has a major role in male reproduction and antioxidative mechanisms. Although deficiency of this element can result in damages to the body's organs, this metalloid can induce deleterious effects in organisms by causing oxidative stress. This study assessed the spermatotoxicity of selenium nanoparticles (SeNPs) in goldfish (Carassius auratus) based on genotoxicity, antioxidant status, sperm quality, and histopathology.MethodsThe fish with an average weight of 70 g (n = 288) were divided into four experimental groups (three replicates) and fed three times a day with SeNPs at different levels of 0, 0.1, 0.5, and 1 mg kg diet for 30 and 60 days.ResultsAfter 30 and 60 days of feeding trial, compared to the control group, spermatocrit percentage markedly decreased at 1 mg kg SeNPs on day 30 as well as at 0.5 and 1 mg kg on day 60 (p < 0.05). Computer-assisted sperm analysis parameters especially VCL, VSL, and VAP decreased in response to SeNPs (p < 0.05). Percentage of fast speed progressive sperm cells was highest in fish fed with 0.1 mg kg SeNPs following the dietary experiment and significantly reduced in a SeNPs dose-dependent manner (p < 0.05). In addition, the levels of Malondialdehyde and Glutathione peroxidase were significantly elevated in seminal plasma of all SeNPs-treated groups (p < 0.05). On day 60, DNA damage of sperm was greatly increased at 1 mg kg SeNPs (p < 0.05). Moreover, the highest percentage of spermatocyte and spermatid were observed at the highest dose of SeNPs while the highest percentage of spermatozoa was recorded at the lowest and moderate SeNPs doses.ConclusionThese findings suggested that non-optimal doses of SeNPs could reduce sperm quality, induce oxidative stress, and DNA damage in sperm, and disrupt testis development.