Arterial hypertension and remodelling of the right ventricle.

BACKGROUND: In the case of long-term and physiological loads (e.g. during pregnancy or regular athletics training), reversible morphological changes occur in the heart - cardiomyocytes undergo hypertrophy; however, this is not accompanied by impairment of left ventricular function or myocyte metabolism. However, in the course of various pathological processes, as time goes by, gradually permanent morphological changes occur. These changes are referred to as remodelling of the heart muscle, which, regardless of the primary cause, can lead to the development of chronic heart failure. MATERIALS AND METHODS: The study was performed on post-mortem material of 35 human hearts obtained from forensic sections and anatomopathological sections of people who died of non-cardiac causes (mainly traffic accidents, suicide attempts, strokes, acute infections); material was fixed in a 4% formalin solution. The hearts were subjected to macro- and microscopic assessment. During microscopic assessment the features of remodelling were evaluated. RESULTS AND CONCLUSIONS: In vivo and echocardiographic tests, as well as macroscopic evaluation of post-mortem material, suggest the presence of some kind of right ventricular muscle remodelling; however, classic microscopic observations, presented in this study, do not provide such unambiguous evidence. Thus, the question arises: why and how the right ventricular function is disturbed, sometimes at early stages of arterial hypertension.

Development of the interatrial wall during the ontogenesis of foetuses and children up to one year of age.

BACKGROUND: The foramen ovale, present in foetal interatrial septum, plays an important role during foetal life. During delivery, foramen ovale closes and becomes fossa ovalis, starting the pulmonary circulation. The aim of our study was to describe the growth of the interatrial wall and changes in location of the foramen ovale, and fossa ovalis during the ontogenesis in the human hearts. MATERIALS AND METHODS: The study was performed on post-mortem material obtained from 92 human hearts from 22nd week of foetal life up to 1 year of age, fixed in a 4% formalin solution. RESULTS: The interatrial wall size in the studied development period was greater in the horizontal than in the vertical dimension. During ontogenesis up to 1 year old, the anterior and inferior parts of the interatrial wall increased their shares considerably by 8% and 6%, respectively. The percentage participation of foramen ovale in the interatrial wall construction in the foetal period formed more than 50% of its size and fairly decreased reaching in infants about 39%. CONCLUSIONS: Our study demonstrated that during ontogenesis, from the foetal period to infancy, the parts of the interatrial wall increase their dimensions unevenly. The foramen ovale growth is smaller, compared to the rest of the interatrial wall development. On the basis of our data we can assume that the foramen ovale centre tends to be found in the postero-inferior quadrant of the interatrial wall (foetuses) and in postero-superior quadrant of the interatrial wall - in infants.

The role of respiratory failure caused by congenital central nervous system abnormalities and the effect of ß-casomorphins in sudden infant death syndrome pathogenesis.

The aim of the paper is to discuss the role of respiratory failure caused by endogenous (both structural and functional) abnormalities in the central nervous system and exogenous food-derived opioid-like peptides in the pathogenesis of sudden infant death syndrome (SIDS). By stimulating µ-opioid receptors, opioid-like peptides may suppress the tonic activity of the respiratory centre in the brain stem.

Haloperidol and clozapine decrease S100B release from glial cells.

Recent meta-analyses showed consistently elevated levels of S100B in serum and cerebrospinal fluid of schizophrenic patients. This finding has been attributed to glial pathology because S100B is produced by astrocytes and oligodendrocytes. However, S100B may be likewise associated with schizophrenia-related disturbances in glial cell as well as adipocyte energy supply and glucose metabolism. The influence of antipsychotic drugs on S100B levels remains unclear, and some studies have suggested that treatment with these drugs may actually contribute to the elevated S100B levels observed in schizophrenic patients. In this study, we explored the effects of the typical antipsychotic haloperidol and the atypical prototype drug clozapine on the release of S100B by astrocytic C6 cells and oligodendrocytic OLN-93 cells. Because of the association between schizophrenia and disturbances in energy metabolism, we assessed the effects of these drugs under basal condition (BC) compared to serum and glucose deprivation (SGD). We found that treatment of C6 and OLN-93 cells with haloperidol and clozapine reduced the release of S100B from C6 and OLN-93 cells under BC and SGD in vitro at a tissue concentration corresponding to the assumed therapeutic dose range of these drugs. These data suggest that elevated levels of S100B in bodily fluids of schizophrenic patients are normalized rather than increased by the effects of antipsychotic drugs on glial cells.

S100B is expressed in, and released from, OLN-93 oligodendrocytes: Influence of serum and glucose deprivation.

S100B (member of a family of proteins that are 100% soluble in ammonium sulfate at neutral pH) has been widely used as astrocyte marker in animal models and in human brain diseases. Recent studies revealed S100B-immunopositivity in oligodendrocytes and O2A oligodendroglial progenitor cells. It is unknown, however, if oligodendrocytes produce S100B themselves, or if the S100B-immunolabeling is caused by binding or absorption of the protein. To address this question, S100B expression and protein release were analyzed in a highly pure oligodendrocytic OLN-93 cell line (from rat), in the astrocytic C6 cell line (from rat) and primary astrocytes. S100B was gene expressed in all cultures, as revealed by reverse transcriptase polymerase chain reaction (RT-PCR) analysis. OLN-93 cells and glial fibrillary acidic protein (GFAP)-negative astrocytes expressed the multiligand receptor for advanced glycation end products (RAGE). S100B protein levels were determined in supernatants and cell homogenates by immunoluminometry under normal conditions and after serum and glucose deprivation (SGD). SGD led to a several-fold increased release of S100B (after 6 and 24 h), which was particularly pronounced in primary astrocytes. Increased S100B in cell homogenates was most notable in OLN-93 cells under SGD, indicating activated S100B synthesis. These cells also showed the highest percentage of dead cells, as determined by propidium iodide-positivity, after SGD. Incubation with 0.5, 2 and 5 microg/l exogenous S100B was not toxic to OLN-93 cells. In conclusion, OLN-93 cells produce more S100B under SGD than astrocytes and are more susceptible to cell death upon SGD, which provokes leakage of S100B. Our data indicate active S100B secretion from astrocytes under SGD since highly elevated levels of S100B were detected in the supernatant despite a low percentage of dead cells. The experimental results provide further evidence for a production/release of S100B in/from oligodendrocytes, e.g. in metabolic stress conditions like cerebral ischemia. Studies on S100B in bodily fluids should be carefully interpreted in order to avoid misleading hypotheses concerning the specific involvement of astrocytes, due to the various cellular sources of S100B.

Early neonatal and postweaning social emotional deprivation interferes with the maturation of serotonergic and tyrosine hydroxylase-immunoreactive afferent fiber systems in the rodent nucleus accumbens, hippocampus and amygdala.

The impact of early emotional experience on the development of serotonergic and dopaminergic fiber innervation of the nucleus accumbens, hippocampal formation and the amygdala was quantitatively investigated in the precocious rodent Octodon degus. Two animal groups were compared: 1) degus which were repeatedly separated from their parents during the first three postnatal weeks, after weaning they were individually reared in chronic social isolation and 2) controls which were reared undisturbed with their families. In the deprived animals 5-hydroxytryptamine-immunoreactive fiber densities were increased in the core region of the nucleus accumbens (up to 126%), in the central nucleus of the amygdala (up to 112%) and in the outer subregion of the dentate gyrus stratum moleculare (up to 149%), whereas decreased fiber densities were detected in the dentate subgranular layer (down to 86%) and in the stratum lacunosum of the hippocampal cornu ammonis region 1 (down to 86%). Tyrosine hydroxylase-immunoreactive fiber densities were increased in the core (up to 115%) and shell region (up to 113%) of the nucleus accumbens of deprived animals, whereas decreased fiber densities (down to 84%) were observed in the hilus of the dentate gyrus. In the stratum granulosum and subgranular layer the fiber densities increased up to 168% and 127% respectively. In summary, these results indicate that the postnatal establishment of the monoaminergic innervation of limbic areas is modulated in response to early emotional experience, and that this environmental morphological adaptation is highly region specific.

Regional distribution of glutamate in the central nervous system of rat terminated by carbon dioxide euthanasia.

Carbon dioxide euthanasia is an established method for the termination of small laboratory animals. It has also been employed by the authors in neurobiological research on the post-mortem glutamate concentration in the structures of rat brains. The following investigations were aimed at optimizing the termination procedure based on the CO2 saturation rate of the inhaled air. Two rates of CO2 flow were applied, and the higher one significantly augmented the glutamate level in the hippocampus and cerebellum. The relationship between this finding and signs of central fear reaction is discussed. The authors conclude that lower rather than higher CO2 flow in euthanasia procedures is gentler and is therefore preferable for use with laboratory animals.

The post-mortem concentration of glutamate in the structures of rat brain as an exponent of short aversive sensory stimulation preceding death.

The problem of post-mortem assessment of short central fear reaction preceding death has been obscure till now. The preliminary results obtained by authors have encouraged them to further research on this topic. Time of aversive sensory stimulation in the presented study was considerably decreased in comparison to the preliminary investigations. The concentration of glutamate was assayed in the selected structures of limbic system and in the cerebellum. The rats were subjected to different simultaneous modalities of sensory stimulation. The involvement of the hippocampi and the cerebellum was revealed as measured by glutamate concentration increase in the whole structures homogenates. The dominant role of mechanical stimulus has been suggested based on the measured increase of glutamate concentration in the whole cerebellum homogenate. By using the presented experimental paradigm a possible application of the biochemical assessment of human brain tissue might be developed in the future for implementing in the field of forensic pathology. The biochemical evaluation of "frozen frames" of neurotransmission can possibly help reconstruct the events which had happened just before sudden and violent death.

Haemorrhages in head tissues during the asphyxiation process.

Two rates of carbon dioxide flow into the termination chamber were applied for the euthanasia of rats. The classical phases of asphyxia were observed in both groups of animals although their course was prolonged in rats exposed to the lower gas flow. The haemorrhages were assessed histologically in the following structures: the pericranium, compact bone and diploë of the skull, sagittal suture, nape muscle and its attachment, and the dura. The haemorrhages appeared regularly in the sagittal suture in all cases from both experimental groups. The possible significance of this phenomenon for the forensic practice was pointed out.

The concentration of glutamate in cerebral tissue as a factor for the assessment of the emotional state before death. A preliminary report.

In this paper the concentration of glutamate in the hemispheres of the brain, the cerebellum and the brain stems of rats exposed to sensory stimulation before death and of control rats are presented. Statistically significant differences in the concentration of this neurotransmitter were found in the hemispheres of the brain in the cases of stress lasting 10 min and 1 min and in the cerebellum after a stress of 10 min. This suggests that it may be possible to diagnose the post-mortem state of emotional tension related to sensoric aversive input which takes place directly before death.

Lead and fluoride content in human bone and hair in the Gdansk region.

The post-mortem lead and fluoride content in the rib bone and hair of 59 persons from the Gdansk region was determined. Fluoride was estimated potentiometrically using a fluoride-specific electrode. Lead was determined by atomic absorption spectrometry. The mean lead concentration in bone was 3.0 micrograms/g and 5.2 micrograms/g in hair. The mean fluoride concentrations were 625.7 micrograms/g and 1.4 micrograms/g in bone and hair, respectively. A positive correlation between the lead content in bone and hair was found in this study (r = 0.308, P < 0.05), no such correlation was observed between the fluoride content in bone and hair. A positive correlation between the fluoride and lead contents in bones and the age of the investigated persons was found. The results obtained correspond well with the comparably moderate exposure to lead and fluoride in the Gdansk region.

Postmortem activity of lactate and malate dehydrogenase in human liver in relation to time after death.

Changes in the activity of lactate (EC 1.1.1.27, LDH) and malate (EC 1.1.1.37, MDH) dehydrogenases were measured in tissue extracts of human liver kept at 5 different temperatures until 35 days after death. The investigated activities decreased in proportion to time of storage which enabled an estimation of time after death by statistical analysis of the data.

Density of trunk tissues of young and medium age people.

In this study the investigations made on about 50 trunk tissue densities are described. They were performed on ten cadavers of both sexes within 24 h of the moment of death. They were 20-40 yr old. The weight of each tissue was measured on a laboratory scale and the volume by placing the tissue in a pycnometer filled with water. The density of 2/3 solid trunk tissues ranged from 1.11 to 1.20 g cm-3. The lowest mean data was obtained for a lung tissue (0.563 g cm-3). The highest density datum known from the literature was that for a compact bone: 1.892 g cm-3. The application of obtained data can be for building dummies (e.g. in experiments of car-crash simulations), as well as in the calculation of inertia values using computerized tomography images.