Ependymal cells surface of human third brain ventricle by scanning electron microscopy.

OBJECTIVES: The ependymal lining of the human brain ventricular system displays distinct structural differences and functional heterogeneity among individual ependymal cells (ECs). To date, multi-ciliated ECs (E1 cells), bi-ciliated ECs (E2 cells), uni-ciliated ECs (E3 cells), ECs without cilia, and ECs with cytoplasmic protrusions have been described in human brain ventricles. METHOD: Using scanning electron microscopy (SEM), we evaluated ependymal samples from 6 defined regions of the third ventricle from 9 human brains. These regions were strictly defined according to the periventricular structures they neighbour with. RESULTS: We observed different structures on the apical surface of the ECs. Various ECs differed from each other by the presence of microvilli, secretory bodies, and a variable number of cilia, which led us to divide the ECs into several exactly specified types according to their apical morphology. CONCLUSION: We found all types of ECs in every examined region with a predominance of particular types of apical surface of ECs in the individual areas (Tab. 4, Fig. 7, Ref. 22).

Body proportions as possible predictors for free gracilis one-stage facial reanimation.

BACKGROUND: Gracilis muscle and its motor nerve belongs to most commonly used flap for facial reanimation. However, it is performed in two steps, which is time consuming. One stage technique can be also performed, but the length of the motor nerve cannot be currently determined before surgery. AIM: The present study was conducted in order to evaluate the body composition on the length and suitability of the motor nerve of gracilis muscle for one stage facial reanimation. METHODS: The gracilis flaps along with the motoric nerve were dissected from 20 fresh cadavers (6 females, 14 males). The length of the lower extremity from superior iliac anterior spine to the bottom of the heel and BMI were measured. Regression analysis of lower extremity length and BMI to the actual length of the motor nerve of gracilis flap was performed. RESULTS: The linear regression analysis showed a positive correlation between the length of the lower limb and the size of the motor nerve length (r = 0.5060, p < 0.05), as well as between the BMI and the size of the motor nerve length (r = 0.5073, p < 0.05). Also, the males had longer motor nerve when compared to females by 13 % (p < 0.05). No difference between females and males in BMI was observed. CONCLUSION: The length from the superior iliac anterior spine, BMI and gender seemed to be potential factors that could help to predict the length of the gracilis flap motor nerve for the one stage facial reanimation. However, further studies evaluating other anatomical factors and validating the possible prediction rule for one stage reanimation success are needed (Fig. 3, Ref. 14).

[Expression of p57 marker in differential diagnosis of complete and partial mole - correlation with DNA analysis]. / Expresia markeru p57 v diferenciálnej diagnostike kompletnej a parciálnej moly - korelácia s DNA analýzou.

Nowadays valid classification of gestational trophoblastic disease, according to the World Health Organisation from the year 2003, divides gestational trophoblastic disease into three groups - molar pregnancies, non-neoplastic non-molar changes of trophoblast and tumours of trophoblast. To the molar pregnancies belong complete, partial, invasive and metastatic hydatidiform mole. In the differential diagnosis it is important to distinguish the complete hydatidiform mole from other forms of gestational trophoblastic disease, because there is an increased risk of malignant transformation of trophoblast cells in complete hydatidiform mole. 10 cases of genetically confirmed diploid complete mole and 10 cases of genetically confirmed triploid partial mole were included into our retrospective study. All cases were examined microscopically in the basic haematoxillin and eosin staining and immunohistochemically with the use of antibodies against human choriogonadotropin hormone, placental alkaline phosfatase and protein p57. Villous cytotrophoblast, stromal villous cells, extravillous trophoblast and decidual cells were p57 positive in all cases of partial hydatidiform mole. All 10 cases of complete hydatidiform mole were p57 negative in stromal villous cells and villous cytotrophoblast. P57 protein is a marker distinguishing complete hydatidiform moles from partial moles.

[The use of cell cultures for in vitro decompression sickness simulation]. / Vyuzitie tkanivových kultúr pri simulovaní dekompresnej choroby.

Recreational and technical diving in the past twenty years have become extraordinary popular. Until then diving was a priority of police, army and scientists. Today more and more enthusiasts are exposed to abnormally high surrounding pressure. To the severest of all risks associated with diving, decompression sickness is the greatest threat. Even the most advanced scientific approaches yet did not reveal the complex mechanisms of decompression sickness formation. The majority of experiments use a live model for decompression sickness studies. This is associated with high fatality rate. The new approach of this scientific study is in the use of an in vitro working media as a means of visualization of gas bubbles due to decompression. The aim of this study is to bring above new approaches in in vitro gas bubble formation during decompression. Main goals are: development of in vitro inert gas bubble visualization and evaluation techniques after a real decompression dive with air a as the diving gas and EANx50 as a decompression gas. We selected cell cultures derived from human fibroblasts B-HEF-2 and cell cultures of mice N2A neuroblasts. We used two decompression profiles. "Explosive" decompression profile with a linear compression to overpressure of 50 bar with an rapid decompression to atmospheric pressure (1 bar). In simulation of a realistic decompression profile we used compressed air as a mean for compression and isocompression breathing gas and an EANx50 blend as a decompression breathing gas. This dive was planned with the use of a VPM-B decompression profile by V-Planner software v.3.62. Our latest experiments show that DNA fragmentation and apoptosis is activated during decompression shock. Use of culture cells can be of great value in further studies of decompression changes in the cellular and subcellular level.

[Legal regulations of forensic DNA analysis in the Slovak Republic]. / Zákonná úprava forenznej DNA analýzy v Slovenskej republike.

As of 1st January 2003 the Law No. 417/2002 Coll. on the Usage of Deoxyribonucleotic Acid Analysis for the Identification of Persons became effective in the Slovak Republic. The Law sets the conditions to take samples due to carry out the forensic DNA analysis, laid down regulations for laboratories approved to perform DNA analysis and at the same time establishes national database of DNA profiles. The author presents short overview of the Law.

Metabolic changes in rats subjected to space flight for 18.5 days in the biosatellite Cosmos 936.

From an investigation of the activity of six glucocorticoid dependent liver enzymes, the existence of chronic, transient, stress-induced hypercorticosteronaemia during flight is probable. This hypercorticosteronaemia arises from weightlessness and induces gluconeogenesis. Weightlessness also caused substantial increases in liver glycogen level. The increased lipolytic activity and that of lipoprotein lipase in several groups of animals could be interpreted as enhancement of fat mobilization and utilization under the influence of stress. As this latter enhancement was also found in ground-based controls, it may have been due to the stress of handling rather than to space flight per se.

The influence of thyroxine on the plasma post-heparin lipolytic activity in rats.

10 min after heparin administration (25 IU per 100 g body weight) the plasma post-heparin lipolytic activity (PHLA) was increased in thyreoidectomized (TECT), hypophysectomized (HX) and hypophysectomized + thyreoidectomized (HX + TECT) rats to the same extent as in intact and sham hypophysectomized controls. However, 60 min after heparin the increase of PHLA persisted only in the TECT, HX and HX + TECT rats. After an administration of thyroxine to TECT rats (25 microgram per 100 g body weight) and also to HX + TECT rats (25 microgram or 100 microgram per 100 g body weight) the PHLA decreased similarly as in controls 60 min after heparin administration. The results suggest that the increased PHLA in hypothyroid rats is caused by the deficiency of thyroid hormones, while TSH released after TECT seems not involved in the regulation of enzymes degrading plasma lipoproteins.

Effect of premature weaning on the fatty acid composition of rat adipose tissue.

The authors described the effect of premature weaning on the fatty acid spectrum in the retroperintoneal fat of female rats during ontogenesis. Premature weaning reduced the lower fatty acid content [decanoic acid C 10:0, lauric acid C 12:0, myristic acid C 14:0] in 30- to 90-day-old rats, but in further development no differences between the amount of these fatty acids were observed in suckled and prematurely weaned animals. These changes concurred with the fatty acid composition of the relevant diet (rat milk and a standard laboratory diet). Changes induced in the amount of other acids by premature weaning were not permanent in character, with the exception of stearic acid C 18:0 and linoleic acid C 18:3, which were raised at 720 days in the retroperitoneal fat of prematurely weaned rats. The amount of lower saturated fatty acids fell with advancing age, whereas oleic C 18:1, linolic C 18:2 and linolenic C 18:3 acid rose.

Protein determination: a comparison of several methods.

A comparison of four methods for the determination of total proteins is presented from the following points of view: - sensitivity; - specificity; - amount of work, chemicals, time and equipment needed for the performance of the determination. The following tests have been examined; Tombs' (absorbancy at 210 nm); Waddell's (difference in absorbancy between 215 and 225 nm); Warburg's (absorbancy at 280 nm); Lowry's (absorbancy at 500 nm after the reaction with phenol reagent). The authors recommend Tombs' method for its outstanding sensitivity, specificity and simplicity as the best of the four.

Blood lipids during normal and early weaning in rats.

In young rats reared with their mothers, a gradual increase of serum cholesterol, triglycerides, phospholipids and total lipids was found between the 7th and the 18th to 22nd postnatal day. Then the concentrations of lipids gradually decrease. Early weaning at the 18th postnatal day causes a precocious decrease of the concentration of all studied lipids in blood so that their values on days 22 and 26 are significantly lower than in animals weaned on the 30th postnatal day. The body weight of early weaned rats decreases only slightly and returns to normal by the 30th day. The changes in serum lipids after early weaning are caused by differences in the amount of cholesterol and other lipids in breast milk, in comparison with those in the standard laboratory diet. Perhaps they may participate in disturbing the homeostatic equilibrium of cholesterol in early weaned rats.

Influence of early weaning on the activity of several enzymes in the liver of rat.

In normally weaned rats the activity of two enzymes in rat liver, i.e. ATP citrate lyase and malic enzyme, gradually increases between the end of the third and the beginning of the fourth postnatal week. The activity of mitochondrial alpha-glycerophosphate oxidase remains unchanged during this period. Early weaning on the 18th postnatal day causes a rapid increase in activity of these enzymes. The impulse for this increase is very probably the change from high fat milk diet to high carbohydrate standard laboratory diet, the decrease of blood lipids, the activation of thyroid gland and changes of sensitivity of hepatic cells towards thyroid hormones. These results showed that early weaning modifies to the known picture of physiological weaning to a great extent.