Developmental parallelism in primates.

The authors examined a large random sample of skulls from two species of macaques: rhesus monkeys and cynomolgus monkeys. The skulls were measured, divided into age and sex groups and thoroughly analysed using statistical methods. The analysis shows that skulls of young rhesuses are considerably more domed, i.e. have better-developed neurocrania, than their adult counterparts. Male and female skulls, on the other hand, were found to be very similar, which means that sexual dimorphism of the rhesus macaque was suppressed. Both of these patterns are known from the human evolutionary pattern. No such parallelism to the development of Homo sapiens was found in the cynomolgus monkeys. The authors conclude that mosaic hominisation trends may have featured in the evolution of all primates. This would mean that apes were not a necessary step on the evolutionary way leading to the development of Homo sapiens, who may have started to evolve at an earlier stage of monkeys.

Comparison of antifungal activity of extracts from different Juglans regia cultivars and juglone.

This study discusses the similarities and differences between the antifungal activity of extracts from walnut green husks of Lake, Koszycki, UO1, UO2 and non-grafted cultivars as well as juglone against the plant pathogenic fungi such as Alternaria alternata, Rhizoctonia solani, Botrytis cinerea, Fusarium culmorum, Phytophthora infestans as well as Ascosphaera apis causing chalkbrood disease in honey bees. The obtained data show that the antifungal activities of the extracts do not always depend on the antifungal activity of juglone, and that they can be modulated by their other components. This fact allows us to conclude that juglone is not the only component of walnut green husk extracts which is responsible for the inhibition of mycelial growth. Phenolic compounds were found to be responsible for activity of the extracts and they can modify antifungal activity of juglone.

Effect of extraction method on the yield of furanocoumarins from fruits of Archangelica officinalis Hoffm.

Optimal conditions for the extraction and analysis of furanocoumarins from fruits of Archangelica officinalis Hoffm. have been determined. The following extraction methods were used: exhaustive extraction in a Soxhlet apparatus, ultrasonication at 25 and 60 degrees C, microwave-assisted solvent extraction in open and closed systems, and accelerated solvent extraction (ASE). In most cases the yields of furanocoumarins were highest using the ASE method. The effects of extracting solvent, temperature and time of extraction using this method were investigated. The highest yield of furanocoumarins by ASE was obtained with methanol at 100-130 degrees C for 10 min. The extraction yields of furanocoumarins from plant material by ultrasonication at 60 degrees C and microwave-assisted solvent extraction in an open system were comparable to the extraction yields obtained in the time- and solvent-consuming exhaustive process involving the Soxhlet apparatus.

Cerebrospinal fluid and blood propofol concentration during total intravenous anaesthesia for neurosurgery.

BACKGROUND: The aim of this paper is to compare the propofol concentration in blood and cerebrospinal fluid (CSF) in patients scheduled for different neurosurgical procedures and anaesthetized using propofol as part of a total intravenous anaesthesia technique. METHODS: Thirty-nine patients (ASA I-III) scheduled for elective intracranial procedures, were studied. Propofol was infused initially at 12 mg kg(-1) h(-1) and then reduced in steps to 9 and 6 mg kg(-1) h(-1). During anaesthesia, bolus doses of fentanyl and cis-atracurium were administered as necessary. After tracheal intubation the lungs were ventilated to achieve normocapnia with an oxygen-air mixture (FI(O(2))=0.33). Arterial blood and CSF samples for propofol examination were obtained simultaneously directly after intracranial drainage insertion and measured using high-performance liquid chromatography. The patients were divided into two groups depending on the type of neurosurgery. The Aneurysm group consisted of 13 patients who were surgically treated for ruptured intracranial aneurysm. The Tumour group was composed of 26 patients who were undergoing elective posterior fossa extra-axial tumour removal. RESULTS: Blood propofol concentrations in both groups did not differ significantly (P>0.05). The propofol concentration in CSF was 86.62 (SD 37.99) ng ml(-1) in the Aneurysm group and 50.81 (26.10) ng ml(-1) in the Tumour group (P<0.005). CONCLUSIONS: Intracranial pathology may influence CSF propofol concentration. However, the observed discrepancies may also result from quantitative differences in CSF composition and from restricted diffusion of the drug in the CSF.

Influence of blood cell transfusion on the presence of propofol in blood components.

BACKGROUND: Understanding propofol distribution in blood is important for optimizing drug usage during TIVA. We studied changes in the propofol concentration in plasma and formed blood elements separated from blood samples taken before and after transfusion of blood cells to patients during TIVA with propofol. MATERIAL AND METHODS: Twelve patients were studied (ASA I-II). Propofol TIVA was performed at infusion rates of 12-9-6 mg x kg(-1) x h(-1). Fentanyl and pancuronium bromide were administered in fractional doses. After tracheal intubation the lungs were ventilated to normocapnia with oxygen-air mixture (FiO2=0.33). Blood samples for propofol analysis were taken 5 min before and 30 min after blood cell transfusion. At that point the propofol infusion rate was 6 mg x kg(-1) x h(-1). Propofol concentrations were measured by means of HPLC. RESULTS: Blood cell transfusion leads to a change in the propofol level in plasma and formed blood elements. The transfusion process lowers the ratio of the plasma propofol concentration to the propofol concentration in formed blood elements. CONCLUSIONS: Formed blood elements show a greater ability to bind propofol after transfusion of 5-15 day erythrocytes.

The influence of blood sample storage time on the propofol concentration in plasma and solid blood elements.

In order to describe the changes of propofol concentration in whole blood and in its components during the blood storage we examined venous blood samples collected from patients anaesthetized either with or without propofol. Blood samples from patients anaesthetized without propofol were spike with propofol 45 min before analysis. Propofol concentration was examined in whole blood, plasma, rinsed formed elements and rinsed and lysed formed blood elements by means of HPLC after 1, 4, 7, 13, 21, 25 and 28 days of storage. There was significant decrease in plasma concentration of propofol during the first few days of sample storage followed by its increase during subsequent days. The opposite phenomenon was observed for formed blood elements. The findings support the hypothesis that propofol distribution between blood components changes in time.

The advantages of cell lysis before blood sample preparation by extraction for HPLC propofol analysis.

Propofol (2,6-diisopropylphenol) is a short-acting drug with a large volume of distribution and high body clearance. It is suitable both for the induction of anaesthesia by bolus injection and the maintenance of anaesthesia by repeated injections or a continuous infusion. Examining the drug concentration its analysis in whole blood is recommended. This results from the fact that propofol molecules strongly bind with plasma proteins and cellular blood constituents and blood composition variations are observed between individuals or in different disease states or resulting from transfusion etc. In most cases the HPLC analysis follows the extraction of samples. The degree of propofol binding with blood cells can be different, depending on the blood type, and it can change in time, which may affect the results of the analysis. The paper discusses and shows the necessity of blood cell lysis before the extraction procedure. The cell lysis makes possible to determine the total amount of propofol in blood independently of the degree of propofol binding with cellular blood constituents and its changes.

The role of human lungs in the biotransformation of propofol.

BACKGROUND: The metabolism of propofol is very rapid, and its transformation takes place mainly in the liver. There are reports indicating extrahepatic metabolism of the drug, and the alimentary canal, kidneys, and lungs are mentioned as the most probable places where the process occurs. The aim of this study was to determine whether the human lungs really take part in the process of propofol biotransformation. METHODS: Blood samples were taken from 55 patients of American Society of Anesthesiologists grade 1-3 scheduled for elective intracranial procedures (n = 47) or for pulmonectomy (n = 8). All patients were premedicated with diazepam (10 mg) administered orally 2 h before anesthesia. Propofol total intravenous anesthesia was performed at the following infusion rates: 12 mg. kg-1. h-1, 9 mg. kg-1. h-1, and 6 mg. kg-1. h-1. Fentanyl and pancuronium bromide were also administered intermittently. After tracheal intubation, the lungs were ventilated to normocapnia with an oxygen-air mixture (fraction of inspired oxygen = 0.33). Blood samples for propofol and 2,6-diisopropyl-1, 4-quinol analysis were taken simultaneously from the right atrium and the radial artery, or the pulmonary artery and the radial artery. The concentration of both substances were measured with high-performance liquid chromatography and gas chromatography-mass spectroscopy. RESULTS: The concentration of propofol in the central venous system (right atrium or pulmonary artery) is greater than in the radial artery, whereas the opposite is observed for propofol's metabolite, 2,6-diisopropyl-1,4-quinol. Higher propofol concentrations are found in blood taken from the pulmonary artery than in the blood collected from the radial artery. CONCLUSIONS: Human lungs take part in the elimination of propofol by transforming the drug into 2,6-diisopropyl-1,4-quinol.

Determining the influence of storage time on the level of propofol in blood samples by means of chromatography.

Due to unsatisfactory equipment efficiency and the time consuming manual procedures of sample preparation, drug analyses in physiological fluids and tissues frequently have to be carried out a few days after the sample collection. This is especially the case with investigations which require the examination of materials for which a large number of samples is necessary. The paper deals with the influence of storing blood samples on the level of propofol in blood and plasma. Propofol (2,6-diisopropylphenol, Diprivan) is a very popular intravenous agent used both for the induction and the maintenance of anaesthesia in human and veterinary patients as well as in laboratory animals. The results obtained show that, due to distinct losses of propofol in samples during their storage, the comparison of data estimated for subsequent days after sampling can lead to misleading or even wrong conclusions. The speed of drug diminution depends both on the type of blood and the anticoagulant used. The established interdependencies between the change in the level of propofol in blood and plasma samples and their storage time show that analogous investigations of other pharmaceutical agents are necessary.

The preparation of specific sorbents with polyclonal antibodies as a ligand for purification of human antithrombin III.

Antithrombin III (AT III) is a serine protease inhibitor active against thrombin, factor X and factor VII. Major hematolytic abnormalities such as disseminated intravascular closing, coagulative vein inflammation, embolism in lungs or brain etc. frequently occur when the level of AT III is low. As a drug AT III is separated from blood preparations by bioselective sorption on sorbents containing heparine as a complementary ligand interacting with AT III molecules. The present paper describes the preparation procedures and the properties of sorbents with chemically bonded AT III antigen. The chromatographic ability of the prepared sorbents to separate AT III from human plasma are discussed in relation to the bonding procedure which was used for AT III antigen immobilization.

Determination of propofol in blood by HPLC. Comparison of the extraction and precipitation methods.

The use of intravenous agents to maintain anesthesia has become increasingly popular since the introduction of propofol. Its popularity results from the fact that in 95% of patients given 2.5 mg propofol per kilogram of body weight, the induction of the drug is rapid and smooth and is followed by rapid recovery with a low incidence of postoperative side effects. In order to study the physiological effects of an intravenous anesthetic agent, it may be necessary to determine its concentration in blood. This paper deals with the high-performance liquid chromatographic analysis of propofol in blood. The concentration values are calculated from the application of extraction and precipitation procedures. Observed differences resulting from the two analytical methods are discussed and interpreted with reference to investigations of blood, plasma, and water solutions of propofol and the precipitation of solid elements in blood.

Determination of residual boron in thermally treated controlled-porosity glasses, by colorimetry, spectrography and isotachophoresis.

Controlled-porosity glasses (CPGs) are often applied as sorbents in chromatography. Besides having high thermal, chemical and mechanical resistance they are characterized by a very narrow pore-size distribution and the choice of mean pore diameter and porosity covers a wide range. In spite of these advantages, their range of use in chromatography is restricted because of their strong adsorption properties, which are connected with the presence of residual boron atoms in the porous CPG skeleton. The boron concentration on the CPG surface can be increased by proper thermal treatment. When CPGs are heated in the range 400-800 degrees the residual boron atoms in the network diffuse from the bulk to the surface. The paper discusses the boron content in porous glasses of different mean pore diameters and the determination of the enrichment of boron on the GPG surface, by three independent methods: colorimetry, spectrography and isotachophoresis.