The paper deals with the population changes of birds inhabiting an extensive area (15.8 km2) dominated by arable land, situated on the Silesia Lowland in south-western Poland. The number of territories was established with the use of the mapping method in the years 1977-1979 and 2001. Some changes in habitat and indices of agricultural production occurred between the two study periods. The 2001 study revealed a clear rise of the species diversity and the area was colonised with 18 new bird species. In the group of agricultural birds the only visible decrease was recorded for the species nesting in or using open cultivated areas, where the total abundance dropped. Within this group the most affected were: Perdix perdix, Vanellus vanellus and Alauda arvensis. The abundance of species inhabiting non-cropped, treeless habitats within open farmland went up. The total abundance of twelve species nesting in hedgerows and woodlots also rose. The severe reduction of the bird populations inhabiting open farmland is most probably associated with much larger environmental changes linked with intensification of agriculture, compared to the small transformations of the non-cropped or marginal habitats (sometimes becoming even larger and more diverse), where bird abundance went up.
Performances and reliability of a human operator are influenced by
fatigue. Influence of fatigue on the human operátor - car driver as a controller in the steering control loop is discussed. Demonstrated are possibilities of fatigue identification from small compensatory movernents of the steering wheel. Preliminary results of using a fatigue indicator based on the analysis of compensatory movernents of the steering wheel are introduced.
Changes in extracellular space (ECS) diffusion parameters, DC potentials and extracellular potassium concentration were studied during single and repeated cortical spreading depressions (SD) in 13-15 (P13-15), 21 (P21) and 90-day-old (adult) Wistar rats. The real-time iontophoretic method using tetramethylammonium (TMA+)-selective microelectrodes was employed to measure three ECS parameters in the somatosensory cortex: the ECS volume fraction α (α = ECS volume/total tissue volume), ECS tortuosity λ (increase in diffusion path length) and the nonspecific TMA+ uptake k’. SD was elicited by needle prick. SD was significantly longer at P13-15 than at P21 and in adults. During SD, α in all age groups decreased from 0.21-0.23 to 0.05-0.09; λ increased from 1.55-1.65 to 1.95-2.07. Ten minutes after SD, α (in adults) and λ (all age groups) increased compared to controls. This increase persisted even 1 hour after SD. When SD was repeated at 1 hour intervals, both α and λ showed a gradual cumulative increase with SD repetition. Our study also shows that cortical SD is, as early as P13, accompanied by severe ECS shrinkage and increased diffusion path length (tortuosity) with values similar to adults, followed by a long-lasting increase in ECS volume and tortuosity when compared to pre-SD values., T. Mazel, F. Richter, L. Vargová, E. Syková., and Obsahuje bibliografii
Patients with obesity and type 2 diabetes often display high levels of the anti-diabetic factor fibroblast growth factor-21 (FGF21), suggesting that the overproduction of FGF21 may result from increased adiposity in an attempt by white adipose tissue (WAT) to counteract insulin resistance. However, the production of FGF21 diabetes in the absence of WAT has not been examined. In this study, we investigated the effects of lipodystrophy in A-ZIP F-1 mice on FGF21 production in relation to diabetes. A-ZIP F-1 mice displayed high FGF21 plasma levels resulting from enhanced FGF21 mRNA expression in the liver. Concomitant enhancement of FGF21 receptor (FGFR1) and glucose transporter 1 (GLUT-1) mRNA expression was observed in the muscles of A-ZIP F-1 mice. Furthermore, the activation of hypothalamic NPY and AgRP mRNA expression positively correlated with plasma levels of FGF21 but not active ghrelin. Our study demonstrates that an increased FGF21 plasma level in lipodystrophic A-ZIP F-1 mice results mainly from up-regulated liver production but does not suffice to overcome the lipodystrophy-induced severe type 2-diabetes and insulin resistance in the liver linked to the augmented liver fat deposition., A. Špolcová, M. Holubová, B. Mikulášková, V. Nagelová, A. Štofková, Z. Lacinová, J. Jurčovičová, M. Haluzík, L. Maletínská, B. Železná., and Obsahuje bibliografii
Pulmonary vein isolation (PVI) is the cornerstone in the
treatment of patients with paroxysmal atrial fibrillation (PAF).
Some research has suggested studies have shown that
modification of ganglionated plexuses (GP), performed with PVI,
could lead to even better outcomes. The aim of this study was to
determine the effect of PVI on the autonomic system. Heart rate
variability (HRV) was used as a marker of autonomic system
activity. Twenty-six PAF patients underwent PVI (PVI group) and
twenty patients underwent PVI plus a GP ablation (GP group). In
each group, 5 min long ECG signals obtained before and after the
electrophysiology EP study were analyzed. Time and frequency
domain parameters were evaluated. Vagal responses during
ablation were observed in 15 (58 %) patients in the PVI group
and in 12 (60 %) patients in the GP group. The change in
normalized power in the low frequency (LF) and in the LF/HF
ratio, before and after ablation, was statistically significant in
both groups (LF/HF 2.6±1.6 before vs. 1.4±1.7 after ablation in
PVI group and LF/HF 3.3±2.6 before vs. 1.8±1.9 after ablation in
the GP group). Relative to heart rate variability parameters, there
were no differences between PVI and PVI + plus GP ablation.
This study was designed to investigate histological changes in skin tissue accompanying immobilization-induced hypersensitivity. Changes in mechanical sensitivity, epidermal thickness, and peripheral nerve profiles in the upper dermis were examined in glabrous skin of rat hind paw after 1, 2, and 4 weeks of ankle joint immobilization by plaster casts. Induction of mechanical hypersensitivity was confirmed after 2 and 4 weeks of joint immobilization. Epidermal thinning and increase in peripheral nerve profiles were observed in skin tissues in immobilized rats. The time course of epidermal thinning and increase in peripheral nerve profiles were similar closely to that of hypersensitivity, with significant differences between the immobilized and control rats after 2 weeks of immobilization, which became even more remarkable at 4 weeks of immobilization. These findings suggest that joint immobilization by cast induces epidermal thinning and increases peripheral nerve profiles in the upper dermis and that these changes might be partly responsible for immobilization-induced hypersensitivity., J. Nakano, ... [et al.]., and Obsahuje seznam literatury