DETERMINATION OF GUSTATORY SUCROSE THRESHOLD IN WATER BY USE OF A LINEAR SUCROSE GRADIENT

A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)).     

Effect of neurotensin on pancreatic function in man

The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.     

The effect of different anamnesis during ontogeny on higher nervous activity in rats.

The consequences of malnutrition, experimental experience and sensory deprivation during early postnatal life were investigated in adult rats. The higher nervous activity of experimental animals was evaluated by means of a battery of tests (exploratory activity, avoidance reaction, preference of a small chamber and a water maze). Rats were divided into 5 groups, i. e. control, trained (with previous experimental experience), light deprived, malnourished naive (12-14 animals in the litter) and malnourished trained. From experimental data obtained it may be concluded that the level of nutrition as well as sensory deprivation or additional stimulation during development are important factors the influence of which persists and modifies the somatic development and the higher nervous activity in adult animals. Light deprived and malnourished rats showed retarded somatic development and worse parameters of higher nervous activity. The difference between groups could be altered by augmented stimulation. Previous experimental experience and intensive handling seems to be an important factor which influences the higher nervous activity of experimental animals.     

Delimitation of the maritime boundary in the gulf of Maine area

The compulsory dispute settlement regime included in the 1982 Law of the Sea Convention is recognized as one of the most comprehensive in a modern international convention. Yet, in the recent application of this regime, the question has arisen as to whether the procedural prerequisites associated with the LOS Convention's compulsory dispute settlement mechanism are so arduous as to avoid binding and compulsory jurisdiction in most instances. This article addresses that question by examining, in particular, the reasoning of the Southern Bluefin Tuna arbitration tribunal, which found Article 281 of Section 1 of the LOS Convention to bar jurisdiction to the compulsory dispute settlement mechanism prescribed by the Convention, and offers suggestions as to how states might distinguish or overcome the barriers imposed by the Southern Bluefin Tuna tribunal in future cases.     

Association of the leukemia inhibitory factor gene mutation and the antiphospholipid antibodies in the peripheral blood of infertile women

To characterize the impact of the potentially functional mutation--the G to A transition at the position 3400 of the leukemia inhibitory factor (LIF; a pluripotent cytokine that plays a central role in the control of the embryo implantation) gene that leads to the exchange of valine with methionine at codon 64 we evaluated the association of the LIF gene mutation and the levels of antiphospolipid antibodies (aPLs) in the peripheral blood of infertile women (the aPLs examination was part of our routine immunological test during the infertility check-up). Eight infertile mutation-positive women were diagnosed with idiopathic infertility (n=5) and endometriosis (n=3) and their levels of aPLs in serum were compared with 115 infertile women without any LIF gene mutation. Enzyme-linked immunosorbent assay was used for the detection of seven antiphospholipid antibodies; the results were statistically assessed by the Fisher's 2 by 2 exact test to evaluate the association of the LIF gene mutations and aPLs in serum of infertile patients. The presence of aPLs was significantly higher in our study group (100%) than in 30% of aPLs-positives in control infertile patients (p = 0.0035) which indicates that the aPLs are elevated in women with LIF gene mutations.     

Testing the extreme value domain of attraction for distributions of beneficial fitness effects

In modeling evolutionary genetics, it is often assumed that mutational effects are assigned according to a continuous probability distribution, and multiple distributions have been used with varying degrees of justification. For mutations with beneficial effects, the distribution currently favored is the exponential distribution, in part because it can be justified in terms of extreme value theory, since beneficial mutations should have fitnesses in the extreme right tail of the fitness distribution. While the appeal to extreme value theory seems justified, the exponential distribution is but one of three possible limiting forms for tail distributions, with the other two loosely corresponding to distributions with right-truncated tails and those with heavy tails. We describe a likelihood-ratio framework for analyzing the fitness effects of beneficial mutations, focusing on testing the null hypothesis that the distribution is exponential. We also describe how to account for missing the smallest-effect mutations, which are often difficult to identify experimentally. This technique makes it possible to apply the test to gain-of-function mutations, where the ancestral genotype is unable to grow under the selective conditions. We also describe how to pool data across experiments, since we expect few possible beneficial mutations in any particular experiment.     

Effects of anesthesia and nociceptive stimulation in an experimental model of brachial plexus avulsion

Unilateral dorsal rhizotomy of brachial plexus nerves (C5-Th1) performed under general anesthesia is known to induce self-mutilation in rats. The aim of this study was to determine the effect of different anesthetic agents, and of pre-rhizotomy nociceptive stimulation on the appearance of self-mutilation. Self-mutilation appeared in 78% of animals after rhizotomy had been performed under pentobarbital anesthesia. When ketamine was used as the general anesthetic, self-mutilation was almost suppressed (13%) and consisted of superficial erosions. Mechanical nociceptive stimulation, when applied just before the induction of ketamine anesthesia and subsequent rhizotomy, provoked self-mutilation in 91% of rats. Furthermore, a serious type of self-mutilation consisting of total amputation of the distal part of the forepaw was present in 28% of all self-mutilating animals after previous nociceptive stimulation. In terms of self-mutilation, these results suggest 1) the crucial role of anesthesia, especially that which involved NMDA receptors (ketamine), and 2) the need of an additional factor to chronic deafferentation, formed either by activity of nociceptive pathways just before rhizotomy (nociceptive stimulation preceding ketamine anesthesia) or by injury discharges (pentobarbital anesthesia).     

The teaching of physiological disciplines in the 3rd Faculty of Medicine,Charles University,Prague, Czech Republic

The physiological disciplines are being taught from the 1st year of medical study up to the end of the 4th year, it means 8 semesters altogether. It is necessary to explain the curriculum of the 3rd Faculty of Medicine, Charles University in Prague. This Faculty has had a new curriculum since 1997, so the first students, who had been taught as to this system, already finished their study. The duration of medical study is 6 years, i.e. 12 semesters. This composed of three cycles: I Basic biomedical sciences. The first two years represent the first cycle, which is based on the integrative principle. II. Principles of clinical medicine. The second cycle is concerned on the problem-based learning. III. Clinical preparation. The third cycle represents clinical application. In the first two years the integrative study is composed of different modules. The first module I A--Structure and functions of human body is the greatest module in the first two years, which is composed of anatomy, histology and embryology, biochemistry and physiology. The module I B--Cell biology and genetics is composed of genetics and cell biology and this module is finished by the examination after two semesters at the end of the first year.