The time course of adenosine, nitric oxide (NO) and inducible NO synthase changes in the brain with sleep loss and their role in the non-rapid eye movement sleep homeostatic cascade

Both adenosine and nitric oxide (NO) are known for their role in sleep homeostasis, with the basal forebrain (BF) wakefulness center as an important site of action. Previously, we reported a cascade of homeostatic events, wherein sleep deprivation (SD) induces the production of inducible nitric oxide synthase (iNOS)-dependent NO in BF, leading to enhanced release of extracellular adenosine. In turn, increased BF adenosine leads to enhanced sleep intensity, as measured by increased non-rapid eye movement sleep EEG delta activity. However, the presence and time course of similar events in cortex has not been studied, although a frontal cortical role for the increase in non-rapid eye movement recovery sleep EEG delta power is known. Accordingly, we performed simultaneous hourly microdialysis sample collection from BF and frontal cortex (FC) during 11 h SD. We observed that both areas showed sequential increases in iNOS and NO, followed by increases in adenosine. BF increases began at 1 h SD, whereas FC increases began at 5 h SD. iNOS and Fos-double labeling indicated that iNOS induction occurred in BF and FC wake-active neurons. These data support the role of BF adenosine and NO in sleep homeostasis and indicate the temporal and spatial sequence of sleep homeostatic cascade for NO and adenosine.     

In vitro gap-directed translesion DNA synthesis of an abasic site involving human DNA polymerases epsilon, lambda, and beta

DNA polymerase (pol) ε is thought to be the leading strand replicase in eukaryotes, whereas pols λ and β are believed to be mainly involved in re-synthesis steps of DNA repair. DNA elongation by the human pol ε is halted by an abasic site (apurinic/apyrimidinic (AP) site). In this study, we present in vitro evidence that human pols λ, β, and η can perform translesion synthesis (TLS) of an AP site in the presence of pol ε, likely by initiating the 3'OHs created at the lesion by the arrested pol ε. However, in the case of pols λ and β, this TLS requires the presence of a DNA gap downstream from the product synthesized by the pol ε, and the optimal gap for efficient TLS is different for the two polymerases. The presence of gaps did not affect the TLS capacity of human pol η. Characterization of the reaction products showed that pol β inserted dAMP opposite the AP site, whereas gap filling synthesis by pol λ resulted in single or double deletions opposite the lesion. The synthesis up to the AP site by pol ε and the subsequent TLS by pols λ and β are not influenced by human processivity factor proliferating cell nuclear antigen and human single-stranded DNA-binding protein replication protein A. The bypass capacity of pol λ at the AP site is greatly reduced when a truncated form of the enzyme, which has lost the BRCA1 C-terminal and proline-rich domains, is used. Collectively, our in vitro results support the existence of a mechanism of gap-directed TLS at an AP site involving a switch between the replicative pol ε and the repair pols λ and β.     

Chlorophyllase 1, a damage control enzyme, affects the balance between defense pathways in plants

Accumulation of reactive oxygen species (ROS) is central to plant response to several pathogens. One of the sources of ROS is the chloroplast because of the photoactive nature of the chlorophylls. Chlorophyllase 1 (encoded by AtCLH1) of Arabidopsis thaliana is quickly induced after tissue damage (e.g., caused by the bacterial necrotroph Erwinia carotovora or the necrotrophic fungus Alternaria brassicicola). RNA interference silencing of AtCLH1 resulted in failure to degrade free chlorophyll after tissue damage and in resistance to E. carotovora. Both inoculation with E. carotovora and exposure to high light caused elevated accumulation of hydrogen peroxide in AtCLH1 silenced plants. This was accompanied by expression of marker genes for systemic acquired resistance and induction of antioxidant defenses. Interestingly, downregulation of AtCLH1 resulted in increased susceptibility to A. brassicicola, resistance to which requires jasmonate signaling. We propose that AtCLH1 is involved in plant damage control and can modulate the balance between different plant defense pathways.     

The Effect of Personality on Daily Life Emotional Processes

Personality features are associated with individual differences in daily emotional life, such as negative and positive affectivity, affect variability and affect reactivity. The existing literature is somewhat mixed and inconclusive about the nature of these associations. The aim of this study was to shed light on what personality features represent in daily life by investigating the effect of the Five Factor traits on different daily emotional processes using an ecologically valid method. The Experience Sampling Method was used to collect repeated reports of daily affect and experiences from 104 healthy university students during one week of their normal lives. Personality traits of the Five Factor model were assessed using NEO Five Factor Inventory. Hierarchical linear modeling was used to analyze the effect of the personality traits on daily emotional processes. Neuroticism predicted higher negative and lower positive affect, higher affect variability, more negative subjective evaluations of daily incidents, and higher reactivity to stressors. Conscientiousness, by contrast, predicted lower average level, variability, and reactivity of negative affect. Agreeableness was associated with higher positive and lower negative affect, lower variability of sadness, and more positive subjective evaluations of daily incidents. Extraversion predicted higher positive affect and more positive subjective evaluations of daily activities. Openness had no effect on average level of affect, but predicted higher reactivity to daily stressors. The results show that the personality features independently predict different aspects of daily emotional processes. Neuroticism was associated with all of the processes. Identifying these processes can help us to better understand individual differences in daily emotional life.     

Characterization of a New Epidemic Necrotic Pyoderma in Fur Animals and Its Association with Arcanobacterium phocae Infection

A new type of pyoderma was detected in Finnish fur animals in 2007. The disease continues to spread within and between farms, with severe and potentially fatal symptoms. It compromises animal welfare and causes considerable economic losses to farmers. A case-control study was performed in 2010–2011 to describe the entity and to identify the causative agent. Altogether 99 fur animals were necropsied followed by pathological and microbiological examination. The data indicated that the disease clinically manifests in mink (Neovison vison) by necrotic dermatitis of the feet and facial skin. In finnraccoons (Nyctereutes procyonoides), it causes painful abscesses in the paws. Foxes (Vulpes lagopus) are affected by severe conjunctivitis and the infection rapidly spreads to the eyelids and facial skin. A common finding at necropsy was necrotic pyoderma. Microbiological analysis revealed the presence of a number of potential causative agents, including a novel Streptococcus sp. The common finding from all diseased animals of all species was Arcanobacterium phocae. This bacterium has previously been isolated from marine mammals with skin lesions but this is the first report of A. phocae isolated in fur animals with pyoderma. The results obtained from this study implicate A. phocae as a potential causative pathogen of fur animal epidemic necrotic pyoderma (FENP) and support observations that the epidemic may have originated in a species -shift of the causative agent from marine mammals. The variable disease pattern and the presence of other infectious agents (in particular the novel Streptococcus sp.) suggest a multifactorial etiology for FENP, and further studies are needed to determine the environmental, immunological and infectious factors contributing to the disease.     

Ordination analysis and bioindices based on zoobenthos communities used to assess pollution of a lake in southern Finland

The suitability of an ordination method, detrended correspondence analysis (DCA), was tested in assessing the degree of pollution of a large lake on the basis of the zoobenthos communities. Lake Etelä-Saimaa, in southern Finland, was originally oligotrophic but is now heavily loaded by effluents from the wood-processing industry. Comparison between areas was complicated by variation in the water depths of the lake sub-basins. A horizontal pollution gradient could, however, easily be detected by means of the DCA in both the profundal and sublittoral zones. The benthic quality index (BQI) based on the composition of the profundal chironomid fauna failed at some stations because the indicator species were lacking, despite enlargement of the indicator species pool. The BQI based on the oligochaetes could be calculated at almost all the stations. This index was modified by altering the empirical constants for two species. Diversity indices and the occurrences of single species had a limited value in the water quality assessment. The study concluded that DCA ordination is a powerful tool in evaluation of pollution. The method gives the best results when the sampling network is carefully planned and the material represents all sections of the underlying environmental gradients, e. g. a gradient from oligotrophy to eutrophy or heavy pollution.     

Temperature and soil fertility as regulators of tree line Scots pine growth and survival—implications for the acclimation capacity of northern populations

The acclimation capacity of leading edge tree populations is crucially important in a warming climate. Theoretical considerations suggest that adaptation through genetic change is needed, but this may be a slow process. Both positive and catastrophic outcomes have been predicted, while empirical studies have lagged behind theory development. Here we present results of a 30‐year study of 55,000 Scots pine (Pinus sylvestris) trees, planted in 15 common gardens in three consecutive years near and beyond the present Scots pine tree line. Our results show that, contrary to earlier predictions, even long‐distance transfers to the North can be successful when soil fertility is high. This suggests that present northern populations have a very high acclimation capacity. We also found that while temperature largely controls Scots pine growth, soil nutrient availability plays an important role—in concert with interpopulation genetic variation—in Scots pine survival and fitness in tree line conditions. These results suggest that rapid range expansions and substantial growth enhancements of Scots pine are possible in fertile sites as seed production and soil nutrient mineralization are both known to increase under a warming climate. Finally, as the ontogenetic pattern of tree mortality was highly site specific and unpredictable, our results emphasize the need for long‐term field trials when searching for the factors that control fitness of trees in the variable edaphic and climatic conditions of the far North.     

Permanent night workers´ sleep and psychosocial factors in hospital work. A comparison to day and shift work

ABSTRACT

We aimed to study whether permanent night workers sleep and psychosocial factors differ from day workers and shift workers. The participants (n = 9 312, 92% females, average age 45 years, most commonly nurses and departmental secretaries) were day workers (DW, n = 2 672), shift workers (SW, n = 6 486) and permanent night workers (PNW, n = 154). The Finnish Public Sector survey responses from six hospital districts from 2012 were combined to payroll data from 91 days preceding the survey. The data were analyzed using Pearson χ²-test, one-way ANOVA and multinomial logistic regression analysis. The PNWs reported slightly longer average sleep length than the SWs or the DWs (7:27 vs. 7:13 and 7:10 h, p < 0.001). The PNWs reported least often difficulties in maintaining sleep (p < 0.001) compared to the SWs and the DWs. The PNWs reported most often difficulties to fall asleep and fatigue during free-time (p-values <0.001). The DWs and PNWs experienced less often work-life conflict than the SWs (25 and 26 vs. 38%, p < 0.001). The PNWs were more often satisfied with autonomy at work and appreciation and fair treatment by colleagues than the DWs or the SWs (p < 0.001). The SWs and PNWs reported remarkably higher occurrence of verbal (p < 0.001, OR 3.71, 95% CI 3.23–4.27 and OR 7.67, 95% CI 5.35–10.99, respectively) and physical workplace violence (p < 0.001, OR 9.24, 95% CI 7.17–11.90 and OR 28.34, 95% CI 16.64–43.06, respectively) compared to DWs. Conclusively, PNWs reported contradictory differences in sleep quality compared to DWs and SWs. PNWs are more often satisfied with their colleagues and autonomy at work than DWs or SWs but face workplace violence remarkably more often.     

Joint Russian—Finnish study of radioactive contamination in the NW part of Lake Ladoga

In August 1992 a joint Russian-Finnish expedition was arranged to the NW part of Lake Ladoga to study radioactive contamination in the region. Special attention was paid to the area surrounding the Heinämaa Islands, where the wreck of the former mine carrier ship Kit had been lying about 30 years before it was moved to Novaya Zemlya in 1991. During this period the wreck had been used as a store for radioactive waste containing principally ⁹⁰Sr, ¹³⁷Cs and ^239,24OPu. Lake water, bottom sediment and some biological samples were collected for strontium, plutonium and gammaspectrometric analyses. In all the samples the radioactivity concentrations were very low, indicating radioactive contamination of about the same level as caused by global fallout in the 1960's and the Chernobyl fallout in the area. Only in two water samples taken close to the former site of the wreck slightly elevated ^239,240Pu concentrations were detected. The great water volume of Lake Ladoga and effective water exchange at the wreck site may explain the very low levels of radioactive wastes detected in the aquatic environment.     

Accessible hyaluronan receptors identical to ICAM-1 in mouse mast-cell tumours

Immunohistochemical studies of the hyaluronan (HA)-receptor (R), originally found on liver endothelial cells (LEC) and related to the intercellular adhesion molecule 1 (ICAM-1), showed that polyclonal antibodies against HARLEC (HA receptor on LEC) also stain structures in mouse mastocytomas, mainly vessels. To test if intravenously administered HA might target the tumour receptorsin vivo, mice carrying an inoculated mastocytoma in one hind leg muscle were injected in the tail vein with¹²⁵I-tyrosine (T)-labelled HA and killed 75 min after injection when organs and tissues were checked for radioactivity. When doses exceeding the binding capacity of the liver were injected, a significant increase in radioactivity (up to five-fold) within the tumour tissue was found. The weight adjusted difference between control and tumour tissue was greater for smaller tumours, probably due to necrosis in the larger. HA-staining of tumours from animals receiving¹²⁵I-T-HA, showed HA in areas that also stained weakly for ICAM-1 using monoclonal antibodies. ICAM-1 staining was dramatically increased after hyaluronidase treatment of the sections, indicating that the HA is bound to these receptors and thereby blocks antibody recognition.Abbreviations ICAM-1 intercellular adhesion molecule 1 - HA hyaluronan - HARLEC hyaluronan receptor on liver endothelial cells - MW molecular weight