Effects of the propofol combination anesthesia on the intrinsic blood-clotting system

Fat emulsions can cause changes in blood-clotting and fibrinolysis. The aim of this study was to examine the relation between the use of the short-acting hypnotic propofol and alteration of the blood clotting system. In a double-blind randomized study, 36 patients with an aortocoronary bypass operation were given either midazolam/fentanyl or propofol/alfentanil. Eleven blood samples were taken at fixed times pre-, intra- and postoperatively to determine changes caused by the anesthetic agents on the hemostaseologic parameters during the whole operation. Perioperative blood pressures of both groups were measured at seven fixed points. From the beginning of the extracorporeal circulation (ECC) to the end of the operation, the measured values of the factor XIIa- and kallikrein-like activity in the propofol group were significantly higher than those of the midazolam group. Also the values of the kallikrein inhibition capacity and the indicators of fibrinolysis (t-PA and D-dimers) suggest a stronger activation of the contact phase at the start of the recirculation and as a result of it a stronger fibrinolysis within the propofol group. Besides, the hypotensive side-effect in the propofol group was evident in contrast to the midazolam group. With this investigation, a correlation between the application of propofol/alfentanil, contact phase activation with activation of the kallikrein-kinin-bradykinin system and the observed hypotension can be set up.     

Increased adsorption of high molecular weight kininogen to heparin-coated artificial surfaces and correlation to hemocompatibility

During the past 10 years investigations have demonstrated that heparin-coated devices used for extracorporeal circuits show an improved hemocompatibility. We investigated the pathway of adsorption of plasma proteins at heparin-coated artificial surfaces and the further activation of the humoral and cellular defense mechanisms of the blood. Twenty milliliters of fresh human blood (1 IU heparin/ml) filled a 50 cm long tubes (with and without covalent heparin-coating), prepared as an in vitro "Closed-Loop" model and recirculated at a temperature of 37 degrees C. After 5, 15, 30, 60 and 120 min fibrinogen and high molecular weight kininogen (HMWK) adsorption was measured by a newly developed modified ELISA technique. In addition, changes in coagulation and platelet activation were measured by well established assays. High concentrations of fibrinogen were detected after very short blood material contact, both on uncoated as well as heparin-coated tubes. However, high amounts of HMWK were only found on the heparin-bonded surfaces. In addition, the concentrations of the soluble coagulation marker prothrombin fragment F1+2 and the marker for platelet activation beta-thromboglobulin were significantly higher in the non-coated tubes. We presume that adsorption of HMWK to heparin-coated surfaces contributes to the improved hemocompatibility of these bondings.     

Seasonal variation of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in endemic area of visceral leishmaniasis, Campo Grande, state of Mato Grosso do Sul, Brazil

The seasonal distribution of Lutzomyia longipalpis was studied in two forested and five domiciliary areas of the urban area of Campo Grande; MS, from December 2003 to November 2005. Weekly captures were carried out with CDC light traps positioned on ground and in the canopy inside a residual forest and on the edge (ground) of a woodland and in at least one of the following ecotopes in peridomiciles-a cultivated area, a chicken coop, a pigsty, a kennel, a goat and sheep shelter and an intradomicile. A total of 9519 sand flies were collected, 2666 during the first year and 6853 during the second. L. longipalpis was found throughout the 2-year period, presenting smaller peaks at intervals of 2-3 months and two greater peaks, the first in February and the second in April 2005, soon after periods of heavy rain. Only In one of the woodlands was a significant negative correlation (p<0.05) between the number of insects and temperature during the first year and the climatic factors (temperature, RHA and rain) was observed. In the domiciliary areas in four domiciles some positive correlations (p< or =0.05) occurred in relation to one or more climatic factors; however, the species shows a clear tendency to greater frequency (72%) in the rainy season than in the dry (28%). Thus, we recommend an intensification of the VL control measures applied in Campo Grande, MS, during the rainy season with a view to reducing the risk of the transmission of the disease.     

Bidirectional interlocus concerted evolution following allopolyploid speciation in cotton (Gossypium).

Polyploidy is a prominent process in plant evolution; yet few data address the question of whether homeologous sequences evolve independently subsequent to polyploidization. We report on ribosomal DNA (rDNA) evolution in five allopolyploid (AD genome) species of cotton (Gossypium) and species representing their diploid progenitors (A genome, D genome). Sequence data from the internal transcribed spacer regions (ITS1 and ITS2) and the 5.8S gene indicate that rDNA arrays are homogeneous, or nearly so, in all diploids and allopolyploids examined. Because these arrays occur at four chromosomal loci in allopolyploid cotton, two in each subgenome, repeats from different arrays must have become homogenized by interlocus concerted evolution. Southern hybridization analysis combined with copy-number estimation demonstrate that this process has gone to completion in the diploids and to completion or near-completion in all allopolyploid species and that it most likely involves the entire rDNA repeat. Phylogenetic analysis demonstrates that interlocus concerted evolution has been bidirectional in allopolyploid species--i.e., rDNA from four polyploid lineages has been homogenized to a D genome repeat type, whereas sequences from Gossypium mustelinum have concerted to an A genome repeat type. Although little is known regarding the functional significance of interlocus concerted evolution of homeologous sequences, this study demonstrates that the process occurs for tandemly repeated sequences in diploid and polyploid plants. That interlocus concerted evolution can occur bidirectionally subsequent to hybidization and polyploidization has significant implications for phylogeny reconstruction, especially when based on rDNA sequences.     

Genetic counselling and prenatal diagnosis in disorders of the mitochondrial energy metabolism

Summary Point mutations in mitochondrial DNA, as found in MELAS, MERRF, NARP and other syndromes, are inherited via the maternal lineage. Genetic counselling can be beneficial, but prenatal diagnosis is not advantageous in these syndromes. Empirical data about the recurrence risk can be applied in Leber disease (LHON). Mitochondrial disorders not associated with a point mutation have a sporadic nature (large deletions/duplications in mitochondrial DNA) or are transmitted according to Mendelian laws. Autosomal dominant inheritance is likely to be found in disorders with depletion of mitochondrial DNA. X-linked mode of inheritance is seen in Menkes disease, Barth syndrome, and in deficiencies of the E₁ subunit of the pyruvate dehydrogenase complex. Mutation analysis or linkage studies can be applied for carrier detection and prenatal diagnosis in these three types of mitochondriopathies. The majority of the disorders with a disturbed mitochondrial energy metabolism are likely inherited in an autosomal recessive mode. Prenatal diagnosis can be performed in the cases of cytochromec oxidase and NADH dehydrogenase deficiencies in chorionic villi in selected families.     

The first record of American visceral leishmaniasis in domestic cats from Rio de Janeiro, Brazil

This paper is the first to report visceral leishmaniasis in domestic cats (Felis catus domesticus) from an endemic area in Rio de Janeiro state, Brazil. A relatively high seroprevalence of 25% was observed although none of them have presented any symptom. Our results support the observation of previous authors, suggesting that cats may be considered as alternative domestic hosts of visceral leishmaniasis and should be included in serological investigations performed in endemic areas.