Motor and neurochemical correlates of aggressive behavior in male mice

We tested aggressive behavior in male albino mice by placing two individuals in one cage. Three successive tests with one-day-long intervals were performed; pairs were formed in a randomized order. Three animal groups, I-III, were classified according to the test results. These were absolute dominants, an intermediate group (animals were sometimes winners in conflicts, sometimes were defeated, or demonstrated no aggressive behavior), and submissive individuals (defeated in all cases). One day before testing and 1 h after each test, the intensity of motor activity (duration and velocity of running in a locomotion wheel ) was measured in all animals. Three days after testing, we measured the levels of noradrenaline (NA)and serotonin (ST) in the hypothalamus and those of NA and adrenaline (A) in the blood. Mice of groups I and II demonstrated high background indices of locomotor activity, while in group III these indices were comparatively low. In the course of testing, these indices in group I were in general preserved, while in groups II and III they dropped significantly. In mice of group I, the highest levels of NA in the hypothalamus and blood, high NA/ST ratio in the hypothalamus, and high NA/A ratio in the blood were observed. Animals of group II were characterized by intermediate levels of NA and ST in the hypothalamus together with rather high concentrations of A and the lowest NA/A ratio in the blood. In mice of group III, the highest level of ST and the lowest NA/ST ratio in the hypothalamus, as well as an intermediate NA/A ratio in the blood, were observed. We conclude that, generally, the response of an animal to emotional stress related to an antagonistic conflict can be classified into three types. These are an NA-ergic type in dominants, an intermediate A-ergic type, and an ST-ergic (vagotonic) type in submissive individuals. These types correlate with the three ethological models of behavior, struggle, escape, and catatonia.Neirofiziologiya/Neurophysiology, Vol. 36, No. 4, pp. 297–305, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Fat Storage-inducing Transmembrane Protein 2 Is Required for Normal Fat Storage in Adipose Tissue

Triglycerides within the cytosol of cells are stored in a phylogenetically conserved organelle called the lipid droplet (LD). LDs can be formed at the endoplasmic reticulum, but mechanisms that regulate the formation of LDs are incompletely understood. Adipose tissue has a high capacity to form lipid droplets and store triglycerides. Fat storage-inducing transmembrane protein 2 (FITM2/FIT2) is highly expressed in adipocytes, and data indicate that FIT2 has an important role in the formation of LDs in cells, but whether FIT2 has a physiological role in triglyceride storage in adipose tissue remains unproven. Here we show that adipose-specific deficiency of FIT2 (AF2KO) in mice results in progressive lipodystrophy of white adipose depots and metabolic dysfunction. In contrast, interscapular brown adipose tissue of AF2KO mice accumulated few but large LDs without changes in cellular triglyceride levels. High fat feeding of AF2KO mice or AF2KO mice on the genetically obese ob/ob background accelerated the onset of lipodystrophy. At the cellular level, primary adipocyte precursors of white and brown adipose tissue differentiated in vitro produced fewer but larger LDs without changes in total cellular triglyceride or triglyceride biosynthesis. These data support the conclusion that FIT2 plays an essential, physiological role in fat storage in vivo.     

Proliferating cell nuclear antigen (PCNA) as a proliferative marker during embryonic and adult zebrafish hematopoiesis

We investigated the expression of proliferative cell nuclear antigen (PCNA) in zebrafish to delineate the proliferative hematopoietic component during adult and embryonic hematopoiesis. Immunostaining for PCNA and enhanced green fluorescence protein (eGFP) was performed in wild-type and fli1-eGFP (endothelial marker) and gata1-eGFP (erythroid cell marker) transgenic fish. Expression of PCNA mRNA was examined in wild-type and chordin morphant embryos. In adult zebrafish kidney, the renal tubules are surrounded by endothelial cells and it is separated into hematopoietic and excretory compartments. PCNA was expressed in hematopoietic progenitor cells but not in mature neutrophils, eosinophils or erythroid cells. Some PCNA+ cells are scattered in the hematopoietic compartment of the kidney while others are closely associated with renal tubular cells. PCNA was also expressed in spermatogonial stem cells and intestine crypts, consistent with its role in cell proliferation and DNA synthesis. In embryos, PCNA is expressed in the brain, spinal cord and intermediate cell mass (ICM) at 24 h-post fertilization. In chordin morphants, PCNA is significantly upregulated in the expanded ICM. Therefore, PCNA can be used to mark cell proliferation in zebrafish hematopoietic tissues and to identify a population of progenitor cells whose significance would have to be further investigated.     

Annual pollen traps reveal the complexity of climatic control on pollen productivity in Europe and the Caucasus

Annual PAR (pollen accumulation rates; grains cm^?2 year^?1) were studied with modified Tauber traps situated in ten regions, in Poland (Roztocze), the Czech Republic (two regions in Krkono?e, two in ?umava), Switzerland (4 regions in the Alps), and Georgia (Lagodekhi). The time-series are 10–16 years long, all ending in 2007. We calculated correlations between pollen data and climate. Pollen data are PAR summarized per region (4–7 traps selected per region) for each pollen type (9–14 per region) using log-transformed, detrended medians. Climate data are monthly temperature and precipitation measured at nearby stations, and their averages over all possible 2- to 6-month windows falling within the 20-month window ending with August, just prior to the yearly pollen-trap collection. Most PAR/climate relationships were found to differ both among pollen types and among regions, the latter probably due to differences among the study regions in the habitats of plant populations. Results shared by a number of regions can be summarized as follows. Summer warmth was found to enhance the following year’s PAR of Picea, Pinus non-cembra, Larix and Fagus. Cool summers, in contrast, increase the PAR of Abies, Alnus viridis and Gramineae in the following year, while wet summers promote PAR of Quercus and Gramineae. Wetness and warmth in general were found to enhance PAR of Salix. Precipitation was found to be more important for PAR of Alnus glutinosa-type than temperature. Weather did not have an impact on the PAR of Gramineae, and possibly of Cyperaceae in the same year. Care is advised when extrapolating our results to PAR in pollen sequences, because there are large errors associated with PAR from sediments, due to the effects of taphonomy and sedimentation and high uncertainty in dating. In addition, in pollen sequences that have decadal to centennial rather than near-annual resolution, plant-interaction effects may easily out-weigh the weather signal.     

Physical predictors,behavioural/emotional attributes and neurochemical determinants of dominant behaviour

Significant differences in physical and behavioural/emotional/cognitive predictors and attributes, as well as of neurochemical inducers of behaviour, between dominant and subordinate animals are discussed. It is still unknown whether these factors are the causes of differences between dominants and subordinates, or vice versa whether the differences between dominants and subordinates are the origin of differences in these factors. The possibility is discussed that no differences exist among juveniles in the concentrations of neurochemical agents (known in the literature as determinants of dominance) between the brains of future dominants and future subordinates. We describe a study design that makes the assessment of the ‘original’ neurochemical profile of the brain possible.     

Impact of temperature on Na2Sr(PO4)F:Eu3+ phosphor

In this article, we report the synthesis of Na₂Sr_1‐x(PO₄)F:Eu_x phosphor via a combustion method. The influence of different annealing temperatures on the photoluminescence properties was investigated. The phosphor was excited at both 254 and 393 nm. Na₂Sr_1‐x(PO₄)F:Eu_x³⁺ phosphors emit strong orange and red color at 593 and 612 nm, respectively, under both excitation wavelengths. Na₂Sr_1‐x(PO₄)F:Eu_x³⁺ phosphors annealed at 1050°C showed stronger emission intensity compared with 600, 900 and 1200°C. Moreover, Na₂Sr_1‐x(PO₄)F:Eu_x³⁺ phosphor was found to be more intense when compared with commercial Y₂O₃:Eu³⁺ phosphor. Copyright © 2013 John Wiley & Sons, Ltd.     

Selection of suitable housekeeping genes for expression analysis in glioblastoma using quantitative RT-PCR

Background  

Considering the broad variation in the expression of housekeeping genes among tissues and experimental situations, studies using quantitative RT-PCR require strict definition of adequate endogenous controls. For glioblastoma, the most common type of tumor in the central nervous system, there was no previous report regarding this issue.     

Aggressive behavior, its adaptive function and mechanisms of development of psychosomatic disorders and diseases of adaptation

A correlation between physiologic and behavioral responses to emotional stress and agonistic conflict (triad model), as well as ideas of autonomic-humoral support of subsequent activity suggest that motor activity and situational aggressive behavior are essential final stages of stress reaction and, therefore, mechanisms of adaptation. Failure in final the stage of adaptive response causes mobilization changes to be directed against the host organism itself. This phenomenon forms the basis for psychosomatic disorders. Aggression seems to be an adaptive response not only from ethologic, but from physiologic point of view as well. It has some elements of homeostatic control (together with non-homeostatic functions). Homeostatic role of aggression may be in "elimination" of mobilization metabolic changes caused by stress reaction and physical activity by means of expressive emotional response. Aggression as a non-homeostatic factor has an ethologic function.