Public health response to an imported case of canine melioidosis.

Melioidosis in humans presents variably as fulminant sepsis, pneumonia, skin infection and solid organ abscesses. It is caused by Burkholderia pseudomallei, which in the United States is classified as a select agent, with "potential to pose a severe threat to both human and animal health, to plant health or to animal and plant products" (Federal Select Agent Program, http://www.selectagents.gov/, accessed 22 September 2016). Burkholderia pseudomallei is found in soil and surface water in the tropics, especially South-East Asia and northern Australia, where melioidosis is endemic. Human cases are rare in the United States and are usually associated with travel to endemic areas. Burkholderia pseudomallei can also infect animals. We describe a multijurisdictional public health response to a case of subclinical urinary B. pseudomallei infection in a dog that had been adopted into upstate New York from a shelter in Thailand. Investigation disclosed three human contacts with single, low-risk exposures to the dog's urine at his residence, and 16 human contacts with possible exposure to his urine or culture isolates at a veterinary hospital. Contacts were offered various combinations of symptom/fever monitoring, baseline and repeat B. pseudomallei serologic testing, and antibiotic post-exposure prophylaxis, depending on the nature of their exposure and their personal medical histories. The dog's owner accepted recommendations from public health authorities and veterinary clinicians for humane euthanasia. A number of animal rescue organizations actively facilitate adoptions into the United States of shelter dogs from South-East Asia. This may result in importation of B. pseudomallei into almost any community, with implications for human and animal health.

Rapid fixation and embedding method for immunocytochemical studies of tomato spotted wilt tospovirus (TSWV) in plant and insect tissues.

A new rapid fixation and embedding technique using microwave energy was evaluated for immunolabelling and examination of ultrastructure of plant and insect cells. Tissues in gluteraldehyde-paraformaldehyde were fixed for fifteen seconds in a microwave at 100% power, and dehydrated. Microwave energy was then used to polymerize the London Resin White (LR White) acrylic resin during the embedding process. Embedded specimens were then thin sectioned (90 nm) and treated with anti-tomato spotted wilt tospovirus (TSWV) antiserum followed by protein A-gold label, or antisera against a TSWV encoded nonstructural protein followed by goat anti-rabbit gold label. Using this technique, structural and nonstructural proteins of TSWV were readily detected and specifically labelled in cells of the insect vector, the western flower thrips, Frankliniella occidentalis (Pergande), and in infected cells of the plant species, Emilia sonchifolia L.

Effect of cucurbitacins on mRNA coding for laccase in Botrytis cinerea.

The effect of cucurbitacin and of Ecballium extract on the formation of mRNA coding for laccase was examined in cultures of Botrytis cinerea grown with inducers of laccase formation, in the presence or absence of the inhibitory compounds. RNA was isolated from the cultures and probed with specific DNA probes for laccase. As an internal control, the RNA was probed for Botrytis beta-tubulin mRNA. From an analysis of the results it is clear that cucurbitacin I and Ecballium extract specifically repress the amount of mRNA coding for laccase. This could account for the previously observed repression of laccase formation by cucurbitacins.

Use of the green fluorescent protein for investigations of Paecilomyces fumosoroseus in insect hosts.

The green fluorescent protein (GFP) from the jellyfish Aequorea victoria has been expressed in a variety of prokaryotic and eukaryotic organisms and has been used extensively as a marker in the study of host-pathogen interactions. We have expressed GFP in the entomopathogenic fungus Paecilomyces fumosoroseus through co-transformation with a vector that confers resistance to glufosinate ammonium. All cell types express GFP and were readily detected by fluorescence microscopy. No correlation was observed between the amount of fluorescence and the pattern of vector integration as observed by Southern analysis. Fluorescent hyphae and conidia were easily distinguished on two insect hosts, the Russian wheat aphid, Diuraphis noxia, and the diamondback moth, Plutella xylostella, and blastospores were also detected in the hemolymph of the diamondback moth. GFP-tagged strains of P. fumosoroseus can be used to study the developmental fate of the fungus within its insect hosts.

Pathogenicity of Paecilomyces fumosoroseus isolates to diamondback moth, Plutella xylostella: correlation with spore size, germination speed, and attachment to cuticle.

Infectivity to larvae of the diamondback moth, Plutella xylostella, was compared among eight Paecilomyces fumosoroseus isolates. Isolate infectivity was assessed for correlation with spore length and germination speed. Four isolates applied to P. xylostella cuticle were also compared for number of spores remaining on the cuticle after washing and for percentage germination after 36 h. Infection of larvae inoculated with the different isolates at an average dosage of 4000 conidia/cm2 ranged from 2 to 47%. The correlation of infectivity with spore length and germination speed in broth was highly significant. Fewer spores of the least infective isolate, ARSEF 1576, attached to larval cuticle compared to spores of the more infective isolates ARSEF 3682, 4461, and 4482 (P < 0.05). After 36 h on larval cuticle, the percentage of spores germinated for isolates 1576 and 3682 was 3 and 95%, respectively. Spores of isolate 1576 were smaller, germinated more slowly, and attached to cuticle in smaller numbers than spores of the more infective isolates. Further research will expand our understanding of the mechanisms of virulence among isolates of P. fumosoroseus.

Optimizing sodium balance in hemodialysis.

this paper develops and tests a mathematical model for Na+ kinetics applied to standard hemodialysis. The volume of distribution of exchangeable Na+, dialyzer surface area, blood and dialysis fluid flow rate, target weight loss, treatment duration and the Na+ diffusibility constant are taken into account. The model is used to compute the optimal hour by hour dialysis fluid Na+ concentration required to achieve the prescribed end-dialysis natremia and maintain a constant end-dialysis body Na+ pool, while providing a nearly uniform removal of Na+ over dialysis. The model was preliminary tested on 10 consecutive dialyses in a single patient using special dialyzer which generates a part of ultrafiltrate uncontaminated by dialysate.