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We examined the effects of different shift work schedules and chronic mild stress (CMS) on mood using animal model. The most common international shift work schedules in nursing were applied by three groups of Wistar-rats and a control group with normal light—dark cycle. One subgroup from each group was subjected to CMS. Levels of anxiety and emotional life were evaluated in light—dark box. Differences between the groups according to independent and dependent variables were examined with one- and two-way analysis of variance, with a significance level defined at p < 0.05. Interaction of lighting regimen and CMS was proved to be significant according to time spent in the light compartment and the average number of changes between the light and dark compartments. Results of our examination confirm that the changes of lighting conditions evocate anxiety more prominently than CMS. No significant differences were found between the results of the low rotating group and the control group, supposing that this schedule is the least harmful to health. Our results on the association between the use of lighting regimens and the level of CMS provide evidence that the fast rotating shift work schedule puts the heaviest load on the organism of animals.

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Acta Biologica Hungarica
Authors: Á. Staszny, Enikő Havas, R. Kovács, B. Urbányi, G. Paulovits, Dóra Bencsik, Á. Ferincz, T. Müller, A. Specziár, Katalin Bakos, and Zs. Csenki

Intraspecific morphological variability may reflect either genetic divergence among groups of individuals or response of individuals to environmental circumstances within the frame of phenotypic plasticity. Several studies were able to discriminate wild fish populations based on their scale shape. Here we examine whether the variations in the scale shape in fish populations could be related to genetic or environmental factors, or to both of them. In the first experiment, two inbred lines of zebrafish, Danio rerio (Hamilton 1822) reared under identical environmental conditions were compared. Secondly, to find out what effect environmental factors might have, offsprings were divided into two groups and reared on different diets for 12 weeks. Potential recovery of scales from an environmental effect was also assessed. Experimental groups could successfully be distinguished according to the shape of scales in both experiments, and the results showed that both genetic and environmental factors may notably influence scale shape. It was concluded that scale shape analysis might be used as an explanatory tool to detect potential variability of environmental influences impacting genetically homogeneous groups of fish. However, due to its sensitivity to environmental heterogeneity, the applicability of this technique in identifying intraspecific stock membership of fish could be limited.

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Acta Physiologica Hungarica
Authors: N. Eszes, A. Bohács, Á. Cseh, G. Toldi, A. Bikov, I. Ivancsó, V. Müller, I. Horváth, J. Rigó, B. Vásárhelyi, Gy Losonczy, and Lilla Tamási

Asthmatic inflammation during pregnancy poses a risk for maternal and fetal morbidities. Circulating T cell immune phenotype is known to correlate with airway inflammation (detectable by fractional concentration of nitric oxide present in exhaled breath (FENO)) in non-pregnant allergic asthmatics. The aim of this study was to assess the relationship of peripheral T cell phenotype to FENO and clinical variables of asthma during pregnancy.We examined 22 pregnant women with allergic asthma in the 2nd/3rd trimester. The prevalence of Th1, Th2, regulatory T (Treg) and natural killer (NK) cell subsets was identified with flow cytometry using cell-specific markers. FENO, Asthma Control Test (ACT) total score and lung function were evaluated.Peripheral blood Th1, Th2, Treg, and NK cell prevalence were not significantly correlated to airway inflammation assessed by FENO in asthmatic pregnant women (all cells p > 0.05; study power > 75%). However, an inverse correlation was detected between Th2 cell prevalence and ACT total scores (p = 0.03) in asthmatic pregnancy.Blunted relationship between T cell profile and airway inflammation may be the result of pregnancy induced immune tolerance in asthmatic pregnancy. On the other hand, increased Th2 response impairs disease control that supports direct relationship between symptoms and cellular mechanisms of asthma during pregnancy.

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A comparative study of immunogenicity and efficacy of the oral rabies virus vaccine SAD P5/88 in raccoon dogs and foxes was conducted. The raccoon dogs received 10 (n = 6), 106.3 (n = 6) or 105.7 FFU SAD P5/88 (n = 5) by direct oral application, and subsequently all animals seroconverted. The foxes received 107.2 (n = 4), 106.2 (n = 4), 105.2 (n = 4) and 104.2 FFU SAD P5/88 (n = 5) by the same route. On days 106 and 196 post vaccination 10 raccoon dogs and 16 foxes were challenged with a relevant street virus, respectively. All 10 raccoon dogs vaccinated with 106.3 (n = 5) or 105.7 FFU SAD P5/88 (n = 5) survived the challenge, whereas all control animals (n = 5) died of rabies. Two foxes vaccinated with 104.2 FFU and one fox vaccinated with 105.2 FFU died of rabies on day 7, 17 and 12 post infection, respectively. Also all control foxes succumbed to rabies. Our findings demonstrate that SAD P5/88 is not only an effective vaccine for oral vaccination of foxes but also for that of raccoon dogs.

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Journal of Flow Chemistry
Authors: Dambarudhar Parida, Christophe A. Serra, Rigoberto Ibarra Gómez, Dhiraj K. Garg, Yannick Hoarau, Michel Bouquey, and René Muller

We report on the synthesis of 2-(dimethylamino)ethyl methacrylate by atom transfer radical polymerization (ATRP) in tubular microreactors. Different process parameters, temperature, pressure, and shear rate, were considered to accelerate the reaction. Increase in temperature induced a faster reaction, but controlled nature of ATRP decreased past a threshold value that can be increased up to 95 °C by reducing the residence time. Positive effect of pressure was observed since significant increases in monomer conversion (+12.5 %) and molecular weight (+5,000 g/mol) were obtained. Moreover, polydispersity index was found to decrease from 1.52 at normal pressure to 1.44 at 100 bars. Benefit of pressure was more visible in smaller reaction space (smaller tube diameter). Finally, shear rate has quite an influence on the early stage of the polymerization and is expressed by an increase in the reaction rate. However, the effect was dimed for long residence times.

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Acta Physiologica Hungarica
Authors: Éva Polyák, K. Gombos, B. Hajnal, K. Bonyár-Müller, Sz Szabó, A. Gubicskó-Kisbenedek, K. Marton, and I. Ember

Artificial sweeteners are widely used all over the world. They may assist in weight management, prevention of dental caries, control of blood glucose of diabetics, and also can be used to replace sugar in foods. In the animal experimentation mice were given oral doses of water solutions of table top artificial sweeteners (saccharin, cyclamate based, acesulfame-K based, and aspartame) the amount of maximum Acceptable Daily Intake (ADI) ad libitum. The controls received only tap water with the same drinking conditions as the treated groups. The mice were fed chow ad libitum.We measured food intake and body weight once a week, water and solutions of artificial sweeteners intake twice a week. The data were analysed by statistical methods (T-probe, regression analysis).Consumption of sweeteners resulted in significantly increased body weight; however, the food intake did not change.These results question the effect of non-caloric artificial sweeteners on weight-maintenance or body weight decrease.

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Acta Physiologica Hungarica
Authors: Krisztina Rusai, A. Prokai, C. Juanxing, K. Meszaros, B. Szalay, K. Pásti, V. Müller, U. Heemann, J. Lutz, T. Tulassay, and A. Szabo

Previous experimental data suggest that steroids might have protective effects during hypoxic/ischemic injury of various organs. In this study, the association between dexamethason (Dexa) treatment and the anti-apoptotic SGK-1 was tested in ischemic renal injury. In vitro, HK-2 cells were exposed to 24 h hypoxia, and the effect of Dexa incubation on SGK-1 expression / activation and on cell death was studied. In an in vivo rat model of unilateral renal IR, animals were treated with Dexa, and serum renal function parameters, tissue injury and SGK-1 expression and localization were examined after different reperfusion times (2 h, 4 h and 24 h). Dexa at a dose of 2 mg/L exerted a protective effect on cell survival assessed by LDH release and vital staining paralleled by marked up-regulation of SGK-1. In rats, 2 mg/kg Dexa treatment 24 h prior to ischemia resulted in less severe tissue injury and ameliorated urea nitrogen levels 24 h after reperfusion. Furthermore, SGK-1 expression and phosphorylation were higher in Dexa animals demonstrated by Western blot and immunofluorescence technique. Our results provide novel data on the signalling mechanism of Dexa under hypoxia / ischemia and further support that Dexa emerges as an attractive pharmacological agent for the prevention of ischemic injury.

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Journal of Flow Chemistry
Authors: Christophe A. Serra, Ikram U. Khan, ZhenQi Chang, Michel Bouquey, René Muller, Isabelle Kraus, Marc Schmutz, Thierry Vandamme, Nicolas Anton, Christian Ohm, Rudolf Zentel, Andrea Knauer, and Michael Köhler

Abstract

Capillary-based flow-focusing and co-flow microsystems were developed to produce sphere-like polymer microparticles of adjustable sizes in the range of 50 to 600 μm with a narrow size distribution (CV < 5%) and different morphologies (core-shell, janus, and capsules). Rod-like particles whose length was conveniently adjusted between 400 μm and few millimeters were also produced using the same microsystems. Influence of operating conditions (flow rate of the different fluid, microsystem characteristic dimensions, and design) as well as material parameters (viscosity of the different fluids and surface tension) was investigated. Empirical relationships were thus derived from experimental data to predict the microparticle's overall size, shell thickness, or rods length. Besides morphology, microparticles with various compositions were synthesized and their potential applications highlighted: drug-loaded microparticles for new drug delivery strategies, composed inorganic-organic multiscale microparticles for sensorics, and liquid crystalline elastomer microparticles showing an anisotropic reversible shape change upon temperature for thermal actuators or artificial muscles.

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Journal of Behavioral Addictions
Authors: Matthias Brand, Hans-JÜrgen Rumpf, Zsolt Demetrovics, Astrid MÜller, Rudolf Stark, Daniel L. King, Anna E. Goudriaan, Karl Mann, Patrick Trotzke, Naomi A. Fineberg, Samuel R. Chamberlain, Shane W. Kraus, Elisa Wegmann, JoËl Billieux, and Marc N. Potenza

Abstract

Background

Gambling and gaming disorders have been included as “disorders due to addictive behaviors” in the International Classification of Diseases (ICD-11). Other problematic behaviors may be considered as “other specified disorders due to addictive behaviors (6C5Y).”

Methods

Narrative review, experts' opinions.

Results

We suggest the following meta-level criteria for considering potential addictive behaviors as fulfilling the category of “other specified disorders due to addictive behaviors”:

1. Clinical relevance: Empirical evidence from multiple scientific studies demonstrates that the specific potential addictive behavior is clinically relevant and individuals experience negative consequences and functional impairments in daily life due to the problematic and potentially addictive behavior.

2. Theoretical embedding: Current theories and theoretical models belonging to the field of research on addictive behaviors describe and explain most appropriately the candidate phenomenon of a potential addictive behavior.

3. Empirical evidence: Data based on self-reports, clinical interviews, surveys, behavioral experiments, and, if available, biological investigations (neural, physiological, genetic) suggest that psychological (and neurobiological) mechanisms involved in other addictive behaviors are also valid for the candidate phenomenon. Varying degrees of support for problematic forms of pornography use, buying and shopping, and use of social networks are available. These conditions may fit the category of “other specified disorders due to addictive behaviors”.

Conclusion

It is important not to over-pathologize everyday-life behavior while concurrently not trivializing conditions that are of clinical importance and that deserve public health considerations. The proposed meta-level-criteria may help guide both research efforts and clinical practice.

Open access