CSF lactate dehydrogenase activity in patients with Creutzfeldt-Jakob disease exceeds that in other dementias

The diagnosis of Creutzfeldt- Jakob disease (CJD) is still made by exclusion of other dementias. We now evaluated lactate dehydrogenase (LDH) in the cerebrospinal fluid (CSF) as a possible additional diagnostic tool. CSF LDH levels of patients with CJD ( n = 26) were compared with those in other dementias ( n = 28). LDH isoenzymes were determined in a subset ( n = 9). Total LDH and isoenzyme LDH-1 were significantly higher, whereas the fractions of LDH-2 and LDH-3 were significantly lower in CJD patients. We conclude that in addition to established CSF parameters, LDH and its isoenzymes might serve as a further help to discriminate between CJD and other dementias. Copyright (C) 2004 S. Karger AG, Basel

Progress in and deterrents to orthotopic liver transplantation, with special reference to survival, resistance to hyperacute rejection, and biliary duct reconstruction.

Before I begin, I want to add my own personal reminiscence. I knew Dave Hume for almost 14 years, slightly for the first 4 and well for the last 10. I first talked to him at an elevator entrance at the Greenbrier Hotel in West Virginia, in April, 1959, and for the last time in April, 1973, in the lower lobby of the Century Plaza Hotel in Los Angeles. In May, 1973, I was in the railroad station in Albuquerque, New Mexico, when I learned from my grief-stricken youngest son that Dave was dead. It is strange how the exact details of these and some other memories in between, of the time I spent with Dave Hume, stand out with the same clarity as what I was doing when I learned of the bombing of Pearl Harbor, the assassination of John Kennedy, but very few other things. The most eloquent tribute to Dave Hume I have heard was the briefest, coming from a non-medical friend who told me sadly, “He really was a dynamite guy!

A dynamically consistent analysis of circulation and transports in the southwestern Weddell Sea

International audienceAn inverse model is applied for the analysis of hydrographic and current meter data collected on the repeat WOCE section SR4 in the Weddell Sea in 1989?1992. The section crosses the Weddell Sea cyclonic gyre from Kapp Norvegia to the northern end of the Antarctic Peninsula. The concepts of geostrophy, conservation of planetary vorticity and hydrostatics are combined with advective balances of active and passive properties to provide a dynamically consistent circulation pattern. Our variational assimilation scheme allows the calculation of three-dimensional velocities in the section plane. Current speeds are small except along the coasts where they reach up to 12 cm/s. We diagnose a gyre transport of 34 Sverdrup which is associated with a poleward heat transport of 28×1012 W corresponding to an average heat flux of 15 Wm?2 in the Weddell Sea south of the transect. This exceeds the estimated local flux on the transect of 2 Wm?2. As the transect is located mostly in the open ocean, we conclude that the shelf areas contribute significantly to the ocean-atmosphere exchange and are consequently key areas for the contribution of the Weddell Sea to global ocean ventilation. Conversion of water masses occuring south of the section transform 6.6±1.1 Sv of the inflowing warm deep water into approximately equal amounts of Weddell Sea deep water and Weddell Sea bottom water. The volume transport of surface water equals in the in- and outflow. This means that almost all newly formed surface water is involved in the deep and bottom water formation. Comparison with the results obtained by pure velocity interpolation combined with a hydrographic data subset indicates major differences in the derived salt transports and the water mass conversion of the surface water. The differences can be explained by deviations in the structure of the upper ocean currents to which shelf areas contribute significantly. Additionally a rigorous variance analysis is performed. When only hydrographic data are used for the inversion both the gyre transport and the poleward heat transport are substantially lower. They amount to less than 40% of our best estimate while the standard deviations of both quantities are 6.5 Sv and 37×1012 W, respectively. With the help of long-term current meter measurements these errors can be reduced to 2 Sv and 8×1012 W. Our result underlines the importance of velocity data or equivalent information that helps to estimate the absolute velocities

The complement system in renal homograft recipients

The whole serum complement and its components were studied in 24 recipients of 27 renal homografts. In 12 of 13 instances in which homograft rejection was diagnosed, it was accompanied by significant declines in CH50, IA50, C4, and C3 levels, and to a lesser degree in C1 and C2 levels. Fourteen patients had normal graft function during the postoperative course of study, and in 13 of the 14 the complement levels were within the normal range throughout. In two recipients with systemic lupus erythematosus, very low initial complement levels increased to normal levels following removal of the native kidneys, splenectomy, and the provision of a well-functioning homograft. Anticomplement activity and elevated titers of C1 and C3 inactivators were observed in some patients, but these did not correlate with the changes in CH50. The findings confirm that the complement system participates in renal homograft rejection. © 1972

Enhanced transmission versus localization of a light pulse by a subwavelength metal slit: Can the pulse have both characteristics?

The existence of resonant enhanced transmission and collimation of light waves by subwavelength slits in metal films [for example, see T.W. Ebbesen et al., Nature (London) 391, 667 (1998) and H.J. Lezec et al., Science, 297, 820 (2002)] leads to the basic question: Can a light be enhanced and simultaneously localized in space and time by a subwavelength slit? To address this question, the spatial distribution of the energy flux of an ultrashort (femtosecond) wave-packet diffracted by a subwavelength (nanometer-size) slit was analyzed by using the conventional approach based on the Neerhoff and Mur solution of Maxwell's equations. The results show that a light can be enhanced by orders of magnitude and simultaneously localized in the near-field diffraction zone at the nm- and fs-scales. Possible applications in nanophotonics are discussed.Comment: 5 figure

Geometry-induced asymmetric diffusion

Past work has shown that ions can pass through a membrane more readily in one direction than the other. We demonstrate here in a model and an experiment that for a mixture of small and large particles such asymmetric diffusion can arise solely from an asymmetry in the geometry of the pores of the membrane. Our deterministic simulation considers a two-dimensional gas of elastic disks of two sizes diffusing through a membrane, and our laboratory experiment examines the diffusion of glass beads of two sizes through a metal membrane. In both experiment and simulation, the membrane is permeable only to the smaller particles, and the asymmetric pores lead to an asymmetry in the diffusion rates of these particles. The presence of even a small percentage of large particles can clog a membrane, preventing passage of the small particles in one direction while permitting free flow of the small particles in the other direction. The purely geometric kinetic constraints may play a role in common biological contexts such as membrane ion channels.Comment: published with minuscule change

Kaon properties and cross sections in nuclear medium

Results for the $\pi + N \to \Lambda, \Sigma + K$ reactions in nuclear matter of Ref. nucl-th/0004011 are presented. To evaluate the in-medium modification of the reaction amplitude as a function of the baryonic density we introduce relativistic, mean-field potentials for the initial, final and intermediate mesonic and baryonic states in the resonance model. These vector and scalar potentials were calculated using the quark meson coupling model. Contrary to earlier work which has not allowed for the change of the cross section in medium, we find that the data for kaon production at SIS energies are consistent with a repulsive $K^+$-nucleus potential.Comment: 5 pages, 3 postscript figures included, uses iopart.cls and iopart10.clo (included), presented by K.T. at the 5th International Conference on Strangeness in Quark Matter, July 20 - 25, 2000, Berkeley, California, to be published in the proceedings, J. Phys. G. An explanation has been added in Sec. 3 with a new figur