Partial congenital defect of the left pericardium: angiographic diagnosis and treatment by thoracoscopic pericardiectomy: case report

Twenty-six patients with an intracardiac myxoma underwent surgical resection at our institution from 1977 through 1992. Left atrial myxoma was diagnosed in 22 patients, left ventricular in 1, right atrial in 2, and right ventricular in 1. Six patients were asymptomatic; preoperative symptoms included dyspnea, arrhythmias, embolic episodes, and syncope. The diagnosis was established with transthoracic echocardiography in all cases but one. Surgery was performed in all cases with the aid of cardiopulmonary bypass with moderate hypothermia and cold crystalloid cardioplegia. One patient with a left ventricular myxoma died in a comatose state during the immediate postoperative period. Long-term clinical and echocardiographic evaluation was performed in 19 patients; results were excellent (all the patients were in New York Heart Association functional class I or II), and no recurrences were documented. The clinical characteristics, diagnostic methods, and surgical approach are presented and discussed.     

Solution structure of a DNA duplex containing the exocyclic lesion 3,N4-etheno-2'-deoxycytidine opposite 2'-deoxyguanosine

Vinyl chloride reacts with cellular DNA producing 3,N4-etheno-2'-deoxycytidine (epsilonC) along with other exocyclic adducts. The solution structure of an oligodeoxynucleotide duplex containing an epsilonC.dG base pair was determined by high-resolution NMR spectroscopy and molecular dynamics simulations. NMR data indicated that the duplex adopts a right-handed helical structure having all residues in anti orientation around the glycosylic torsion angle. The epsilonC adduct has a sugar pucker in the C3'-endo/C4'-exo region while the rest of the residues are in the C2'-endo/C3'-exo range. NOE interactions established Watson-Crick alignments for canonical base pairs of the duplex. The imino proton of the lesion-containing base pair resonated as a sharp signal that was resistant to water exchange, suggesting hydrogen bonding. Restrained molecular dynamics simulations generated three-dimensional models in excellent agreement with the spectroscopic data. The refined structures are slightly bent at the lesion site without major perturbations of the sugar-phosphate backbone. The adduct is displaced and shifted toward the major groove of the helix while its partner on the complementary strand remains stacked. The epsilonC(anti).dG(anti) base pair alignment is sheared and stabilized by the formation of hydrogen bonds. The biological implications of structures of epsilonC-containing DNA duplexes are discussed.     

The patterns of oxygen metabolism in the early posthemorrhagic period]

Investigated all links of oxygen homeostasis of patients in early period afterwards surgical stoppage gastro-intestinal bleeding and urgent intravascular volume replacement. Macrodelivery of oxygen (DO2) was reduced in two and more time in comparison with norm predominant in connection with anemia. In spite of the infringement of transport of oxygen through alveolar-capillary membrane (especially in patients with complications and death in early postoperative period), little affected of degree of hemoglobin saturation by oxygen. Despite decrease of erythrocyte zeta-potential, largely expressed in cases of lethal outcome, considerable infringement of passage through microcirculation vessels is fixed was not. The increase of degree of morbidity and anaerobic metabolism in early postoperative period was accompanied of hyperdynamic hemodynamic reaction. The increase of degree of morbidity was accompanied of increase oxygen deficit owing to infringement of oxidoreduction in fabries also.     

The interaction of peripheral blood leukocytes with alpha1-acid glycoprotein, its carbohydrate chains and neoglycoconjugates

The interaction of human peripheral blood leukocytes with alpha 1-acid glycoprotein (AGP), its glycoforms as well as neoglyco-conjugates representing carbohydrate chains of AGP or its fragments was studied by flow cytometry. It was shown that the main target cells for AGP as well as for conjugates of its carbohydrate chains with polyacrylamide (PAA) are monocytes and polymorphonuclear leukocytes but not lymphocytes. The interaction of AGP with monocytes and granulocytes are mediated by its carbohydrate chains: the binding of AGP with cells was inhibited by AGP, AGP oligosaccharides as well as conjugates of oligosaccharides and its fragments with PAA. The data obtained show the existence of monocyte (and granulocyte) receptors which interact with complex type sialooligosaccharides of AGP.     

Memory complaints in epilepsy: correlations with cognitive performance and neuroticism

Experimental results are presented to show that the adhesion force is the single most important limiting factor in high-resolution atomic force microscopy of DNA in air, prepared by the cytochrome-C-assisted spreading method. It is also shown that humidity plays a minor role in the control of probe force. Using a pure carbon film as the substrate to clean the AFM tip prior to imaging, it is demonstrated that 4-6 nm resolution on DNA can be routinely obtained by the atomic force microscope with commercial Si3N4 pyramid cantilevers. We also show that in organic solvents a resolution of up to 3 nm can be obtained under optimal conditions.     

Motion patterns of Nabesna Glacier (Alaska) revealed by interferometric SAR techniques

Nabesna Glacier is one of the longest land-terminus mountain glaciers in North America. However, its flow has never been studied. We derived detailed motion patterns of Nabesna Glacier in winter and spring 1994–1996 from the synthetic aperture radar (SAR) images acquired by the European Remote Sensing satellites (ERS-1 and ERS-2) using interferometric SAR (InSAR) techniques. Special effort was made to assess the accuracy of the motion estimates, and remove data points with high uncertainty from the motion profiles, enabling us to obtain reliable glacier flow patterns along the highly curved main course of Nabesna Glacier. The results, covering 80 km of the 87 km main course of the glacier, were used to delineate four distinctive sections in terms of spatial and temporal variability of the glacier speed: (1) the upper section where glacier flow was apparently random both temporally and spatially presumably due to development of crevasses; (2) the upper-middle section with relatively steady flow around 0.27 to 0.4 m/day; (3) the middle section with a stable pattern of acceleration from 0.27–0.3 m/day to the maximum about 0.67–0.73 m/day, followed by a general deceleration to 0.17–0.33 m/day before reaching (4) the lower section where the glacier motion was generally slow yet highly variable although uncertainty in the estimation is high. Occurrence of the flow maximum, as well as many local maxima and minima at consistent locations over different periods suggests that the valley geometry affect the overall flow pattern. On top of this general trend, many small-scale temporal/spatial variations in the glacier flow patterns were observed along the glacier, especially in the lower sections. On average, the flow speeds were in the range of 0.3 to 0.7 m/day; however this lacks any measurements of summer flow speeds which are expected to be significantly higher.     

Implementation of multipoint connections in an ATM switching network

This paper presents the problems in the implementation of multipoint connections at switching level using the example of an ATM switching network. By choosing the proper routeing mechanism and the appropriate architecture of the switching element, a switching network can gradually be adapted to an increasing share of multipoint traffic. The first section describes the problems with the handling of multipoint connections within a multiple stage connection oriented switching network. In particular this refers to the routeing of the cells through the switching network. Several alternatives on this issue are discussed. Both, the selected approach based on a differentiated self-routeing mechanism and the corresponding cell format are introduced. In the second part of this article several switch architectures are compared in respect of their multipoint capability. It is demonstrated that at present the most promising solution are switching elements based on the principle of central buffering. A single chip solution using this concept is employed in the presented switching network.