Impact of different husbandry conditions on contact and airborne transmission of H5N1 highly pathogenic avian influenza virus to chickens.

Typically highly pathogenic avian influenza (HPAI) viruses spread very rapidly among chickens within sheds. However, the spread was slower than expected for the initial 10 days of the index farm in Japan during 2004. This slow spread, as well as the lack of gross lesions, clinical signs, or high mortality, hindered the field veterinarian from reporting a suspected HPAI outbreak to the veterinary office. To understand the field conditions for the slow virus spread, we examined contact and airborne transmission of the H5N1 virus to chickens in a negative-pressure isolator using various numbers of infected chickens and separate compartments. We found that the contact transmission did occur inefficiently when one or two chickens were infected, whereas the transmission was efficient when four chickens were infected. Airborne transmission of the HPAI virus was also dependent on the number of infected chickens and was less efficient than contact transmission. These data together with field observations suggested that number of infected chickens, chicken house types, and amount of environmental contamination might affect the virus transmission efficiency to chickens.

Nanoparticle probes for quantifying supramolecular determinants of biosurface affinity.

Interactions between macromolecular systems and biosurfaces are complicated by both the complexity of these multivalent interactions and challenges in quantifying affinities. A library of gold nanoparticles (AuNPs) as multivalent probes is used to quantify biosurface affinity, using hair as a model targeted substrate.

[Pulmonary hypertensive crisis after open heart surgery].

Three patients with pulmonary hypertensive crisis (PHC) after open heart surgery for ventricular septal defect are reported. These patients ranged in age from 2 to 47 months, with Rp from 7.0 to 10.6 U.m2, Pp/Ps from 0.67 to 1.0, and Qp/Qs from 1.6 to 1.79. Intraoperative lung biopsy showed pulmonary vascular obstructive disease of Health-Edwards grade 2 in each patient. Atelectasis or pleural effusion on their chest-XP films was found when PHC occurred. The PHC course of the last case was recorded continuously on ABP, PAP and LAP. Administration of prostaglandin-E1 directly through the pulmonary arterial catheter was effective on PHC. Continuous recording of ABP, PAP and LAP during the episode was useful to differentiate PHC from acute left heart failure and/or acute right heart failure.

Unusual paired helical filaments in progressive supranuclear palsy.

Unusual paired helical filaments (PHF) coexisting with single filaments were observed in neurofibrillary degeneration (NFD) in the globus pallidus, subthalamic nucleus, substantia nigra, and pontine tegmentum of a typical case of progressive supra-nuclear palsy (PSP). Each filament had a diameter of 10-12 nm and showed central low density and a smooth contour. The thickest portion of a pair was 22-24 nm in diameter. The periodicity of twist varied from 150 nm to 300 nm, but each PHF had regular periodicity. The present ultrastructural finding is unusual in the neurofibrillary pathology of PSP, and is also different from the PHF found in Alzheimer type NFD.