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Many studies have been conducted on measuring avian influenza viruses and their hemagglutinin (HA) antigens via electrochemical principles; most of these studies have used gold electrodes on ceramic, glass, or silicon substrates, and/or labeling for signal enhancement. Herein, we present a paper-based immunosensor for label-free measurement of multiple avian influenza virus (H5N1, H7N9, and H9N2) antigens using flexible screen-printed carbon nanotube-polydimethylsiloxane electrodes. These flexible electrodes on a paper substrate can complement the physical weakness of the paper-based sensors when wetted, without affecting flexibility. The relative standard deviation of the peak currents was 1.88% when the electrodes were repeatedly bent and unfolded twenty times with deionized water provided each cycle, showing the stability of the electrodes. For the detection of HA antigens, approximately 10-μl samples (concentration: 100 pg/ml–100 ng/ml) were needed to form the antigen–antibody complexes during 20–30 min incubation, and the immune responses were measured via differential pulse voltammetry. The limits of detections were 55.7 pg/ml (0.95 pM) for H5N1 HA, 99.6 pg/ml (1.69 pM) for H7N9 HA, and 54.0 pg/ml (0.72 pM) for H9N2 HA antigens in phosphate buffered saline, and the sensors showed good selectivity and reproducibility. Such paper-based sensors are economical, flexible, robust, and easy-to-manufacture, with the ability to detect several avian influenza viruses.

Eggs of double-crested and pelagic cormorants were collected between 1973 and 1998 from colonies in the Strait of Georgia, BC, Canada, and assayed for concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and non-ortho- and mono-ortho-biphenyls (PCBs). Double-crested cormorant eggs contained (on average) up to 433 ng kg(-1) wet weight 1,2,3,6,7,8-HxCDD, 151 ng kg(-1) 1,2,3,7,8-PnCDD, and 74 ng kg(-1) 2,3,7,8-TCDD, whereas pelagic cormorant eggs contained up to 300, 99, and 28 ng kg(-1) wet weight of these respective congeners. The dominant non-ortho-PCB was CB-126, which ranged as high as 2263 ng kg(-1) in double-crested cormorant eggs. Concentrations of PCDDs and PCDFs fell dramatically in the early 1990s, following both severe restrictions on the use of chlorophenolic wood preservatives and antisapstains and a switch from molecular chlorine bleaching to alternative bleaching technologies at pulp mills in the region. Concentrations of PCBs did not show similar marked declines over time. On the basis of total TEQs > or = 148 ng kg(-1) and previously published documentation of effects in siblings of the cormorant eggs analyzed here, double-crested cormorant young may have exhibited significantly elevated EROD activity and/or brain asymmetries at all colonies from 1973 to 1989 and even at some colonies during the 1990s. Pelagic cormorant eggs collected from a few colonies in 1988-1989 also contained total TEQs greater than the threshold value estimated for double-crested cormorants.

Avian influenza viruses (AIVs) infect a wide range of host species including domestic poultry and wild birds; also, AIVs may infect humans in whom some highly pathogenic viruses (HPAIV) may cause acute fatal disease. Accurate laboratory diagnosis of AIV infections requires time-consuming and logistically complex precautionary measures for shipment of specimens or viruses to avoid biohazard exposure. The feasibility was investigated of the Flinders Technology Associates filter paper (FTA® card) for infectivity of AIVs and to preserve viral RNA for detection by RT-qPCR, sequencing and by DNA microarray assay. The infectivity of AIV subtype H6N2 and HPAIV subtype H5N1 was inactivated completely within one hour after adsorption to the FTA card at room temperature. FTA-adsorbed viral RNA remained stable for five months. Swab samples obtained from chickens infected experimentally with H5N1 virus and spotted directly onto the FTA® cards allowed a sensitive and straightforward diagnosis by RT-qPCR. FTA® cards were also suitable for examination of field samples, although AIV RNA was detected with reduced sensitivity in comparison to direct examination of swab fluids. The use of FTA® cards will facilitate safe transport of samples for molecular diagnosis of AIV avoiding the need for an uninterrupted cold storage.

In December 1993, four reported cases of histoplasmosis among employees in a Michigan pulp paper factory prompted an investigation. A cohort of employees was surveyed to identify additional cases. A case of acute histoplasmosis was defined as an influenza-like illness in a plant employee with the onset of illness during October or November 1993 and laboratory evidence of recent infection with Histoplasma capsulatum. Among the 96 employees surveyed, 18 persons met the case definition; all of these had illness onset during the last week of October in 1993. The attack rate among maintenance employees (16 of 53 [30%]) was much greater than that among nonmaintenance employees (2 of 43 [5%]) (relative risk = 6.5; 95% confidence interval = 1.6 to 26.7; P = 0.003). On October 22, a dry, windy day, one maintenance worker swept bird guano, approximately 10 cm deep, from an adjacent roof < 20 m from the maintenance building. The disturbance of the bird guano was the likely event which caused this outbreak. H. capsulatum remains an important pathogen among immunocompetent hosts. We recommended that the plant authorities (i) discourage birds from roosting at the facility and (ii) use safe procedures for the cleanup and disposal of soil contaminated with bird droppings.

One of the chemical breakdown products of nonylphenol ethoxylates, 4-nonylphenol (4-NP), accumulates in organisms and is of concern as an environmental pollutant due to its endocrine disrupting effects. We measured 4-NP levels in the seawater, sediment, and twelve organisms within the California estuary, Morro Bay, and examined biomagnification of 4-NP using stable isotope abundances (δ(15)N and δ(13)C) to quantify trophic position. 4-NP concentrations in organisms from Morro Bay included 25000±8600 ng g(-1) lw in liver of California sea lion, 14000±5600 ng g(-1) lw in liver of harbor porpoise, 138000±55000 ng g(-1) lw in liver of sea otters, 15700±3600 ng g(-1) lw in liver of seabirds, 36100±6100 ng g(-1) lw in arrow goby fish, 62800±28400 ng g(-1) lw in oysters, and 12700±1300 ng g(-1) lw in mussels. 4-NP levels generally showed a pattern of trophic dilution among organisms in Morro Bay, with exceptions of biomagnification observed between three trophic links: mussel to sea otter (BMF 10.9), oyster to sea otter (BMF 2.2), and arrow goby to staghorn sculpin (BMF 2.7). Our examination of other west coast estuaries of USA and Canada revealed that mean 4-NP concentrations in gobies and mussels from Morro Bay were significantly higher than those from a more urbanized estuary, San Francisco Bay (goby: 11100±3800 ng g(-1) lw) and from a remote estuary, Bamfield Inlet, Canada (goby: 9000±900 ng g(-1) lw, mussel: 6100±700 ng g(-1) lw). Relative to other estuaries worldwide, 4-NP levels in seawater (0.42±0.16 μg L(-1)) and sediment (53±14 ng g(-1) dw) of Morro Bay are low, but gobies and oysters have higher 4-NP levels than comparable fauna.

Background Methods involving the analysis of nucleic acids have become widespread in the fields of traditional biology and ecology, however the storage and transport of samples collected in the field to the laboratory in such a manner to allow purification of intact nucleic acids can prove problematical. Results FTA® databasing paper is widely used in human forensic analysis for the storage of biological samples and for purification of nucleic acids. The possible uses of FTA® databasing paper in the purification of DNA from samples of wildlife origin were examined, with particular reference to problems expected due to the nature of samples of wildlife origin. The processing of blood and tissue samples, the possibility of excess DNA in blood samples due to nucleated erythrocytes, and the analysis of degraded samples were all examined, as was the question of long term storage of blood samples on FTA® paper. Examples of the end use of the purified DNA are given for all protocols and the rationale behind the processing procedures is also explained to allow the end user to adjust the protocols as required. Conclusions FTA® paper is eminently suitable for collection of, and purification of nucleic acids from, biological samples from a wide range of wildlife species. This technology makes the collection and storage of such samples much simpler.