R-plasmid transfer in Salmonella spp. isolated from wastewater and sewage-contaminated surface waters.

A total of 865 Salmonella isolates from wastewaters and sewage-contaminated natural waters were tested for antimicrobial resistance by using NR10 medium and incubation at 43 degrees C. Of the strains, 12.7% were resistant to one or more of the compounds tested, and 30% transferred resistance to an Escherichia coli recipient. The highest minimal inhibitory concentrations were ca. 1,000 micrograms/ml. Transfer frequencies ranged from 10(-3) to 10(-7).     

R-plasmid transfer in Salmonella spp. isolated from wastewater and sewage-contaminated surface waters

A total of 865 Salmonella isolates from wastewaters and sewage-contaminated natural waters were tested for antimicrobial resistance by using NR10 medium and incubation at 43 degrees C. Of the strains, 12.7% were resistant to one or more of the compounds tested, and 30% transferred resistance to an Escherichia coli recipient. The highest minimal inhibitory concentrations were ca. 1,000 micrograms/ml. Transfer frequencies ranged from 10(-3) to 10(-7).     

Phytoplankton composition of the New York Bight and adjacent waters

The New York Bight possesses a diverse assemblage of phytoplanktonwhere seasonal periods of high growth are dominated by several,chain-forming diatoms and a pico-nanoplankton component Thecomposition is similar to other regions of the northeasternshelf, producing late winter-early spring and fall maxima.     

Most probable number methodology for quantifying dilute concentrations and fluxes of Salmonella in surface waters

Aims: To better understand and manage the fate and transport of Salmonella in agricultural watersheds, we developed a culture‐based, five tube–four dilution most probable number (MPN) method for enumerating dilute densities of Salmonella in environmental waters. Methods and Results: The MPN method was a combination of a filtration technique for large sample volumes of environmental water, standard selective media for Salmonella and a TaqMan confirmation step. This method has determined the density of Salmonella in 20‐l samples of pond inflow and outflow streams as low as 0·1 MPN l^?1 and a low 95% confidence level 0·015 MPN l^?1. Salmonella densities ranged from not detectable to 0·55 MPN l^?1 for pond inflow samples and from not detectable to 3·4 MPN l^?1 for pond outflow samples. Salmonella densities of pond inflow samples were associated with densities of Escherichia coli and faecal enterococci that indicated stream contamination with faeces and with nondetectable pond outflow densities of the faecal indicator bacteria. The MPN methodology was extended to flux determinations by integrating with volumetric measurements of pond inflow (mean flux of 2·5 l s^?1) and outflow (mean flux of 5·6 l s^?1). Fluxes of Salmonella ranged from 100 to greater than 10⁴ MPN h^?1. Conclusions: This is a culture‐based method that can detect small numbers of Salmonella in environmental waters of watersheds containing animal husbandry and wildlife. Significance and Impact of the Study: Applying this method to environmental waters will improve our understanding of the transport and fate of Salmonella in agricultural watersheds, and can be the basis of valuable collections of environmental Salmonella.     

Proficiency testing in cytology in New York. Analysis of a 14-year state program

A review of the first 14 years of the New York State Proficiency Testing Program in cytology shows the value of external quality-control evaluation based upon an established standard of performance as a prerequisite for licensure by a regulatory agency. Performance by participating laboratories has improved over the 14-year period. Hospital and independent laboratories had a higher pass rate than did state-run laboratories. Laboratories that did not employ cytotechnologists and performed fewer than 1,000 tests annually tended to have the lowest pass rates and consequently to undergo the most training before retesting and licensing. Overall, the predominant type of error, regardless of specimen type, was false negatives (underreads). Cervicovaginal false-negative errors by cytotechnologists ranged from 2% to 8%; such errors by cytopathologists ranged from 2.1% to 6.9%. Deficiencies and weaknesses detected by proficiency testing were remedied through a combination of surveillance and education.     

Serologic evidence of leptospirosis in woodchucks (Marmota monax) in central New York State.

Serum samples from 153 woodchucks (Marmota monax) from Tompkins County, New York, obtained in 1976 and 1977, were examined by plate agglutination tests for antibodies against five Leptospira antigens. Fourteen sera showed significant titers against either L. hardjo, L. icterohemorrhagiae and/or L. pomona. Reactions against L. hardjo were the most frequent. Woodchucks collected from two dairy farms with histories of bovine leptospirosis did not have a greater prevalence of antibodies than woodchucks collected from other locations. Each of two woodchucks experimentally-inoculated with L. hardjo developed titers to L. hardjo. Maximum titers occurred approximately 30 days post-inoculation. L. hardjo was not observed in urine specimens of these animals.     

Semisolid media for isolation of Salmonella spp. from coastal waters.

The use of two semisolid media (semisolid Rappaport and semisolid Rappaport-Vassiliadis) for the isolation of Salmonella spp. from coastal waters was compared with the use of conventional media. Two hundred and fifty six samples were studied; Salmonella spp. were detected in 83. The semisolid media were the most sensitive, detecting 73 samples instead of the 53 detected by the conventional media (P less than 0.001). The rate of isolation of Salmonella spp. showed an increase of 56.6% when the semisolid media were added to the conventional media, it being possible to detect 54.2% of the total organisms 1 day earlier.     

The emergence of Dinophysis acuminata blooms and DSP toxins in shellfish in New York waters

The dynamics of Dinophysis acuminata and its associated diarrhetic shellfish poisoning (DSP) toxins, okadaic acid (OA) and dinophysistoxin-1 (DTX1) as well as pectenotoxins (PTXs), were investigated within plankton and shellfish in Northport Bay, NY, USA, over a four year period (2008–2011). Over the course of the study, Dinophysis bloom densities ranged from ~10⁴ to 10⁶ cells L⁻¹ and exceeded 10⁶ L⁻¹ in 2011 when levels of total OA, total DTX1, and PTX in the water column were 188, 86, and 2900 pg mL⁻¹, respectively, with the majority of the DSP toxins present as esters. These cell densities exceed – by two orders of magnitude – those previously reported within thousands of samples collected from NY waters from 1971 to 1986. The bloom species was positively identified as D. acuminata via scanning electron microscopy and genetic sequencing (cox1 gene). The cox1 gene sequence from the D. acuminata populations in Northport Bay was 100% identical to D. acuminata from Narragansett Bay, RI, USA and formed a strongly supported phylogenetic cluster (posterior probability = 1) that included D. acuminata and Dinophysis ovum from systems along the North Atlantic Ocean. Shellfish collected from Northport Bay during the 2011 bloom had DSP toxin levels (1245 ng g⁻¹ total OA congeners) far exceeding the USFDA action level (160 ng g⁻¹ total OA of shellfish tissue) representing the first such occurrence on the East Coast of the U.S. D. acuminata blooms co-occurred with paralytic shellfish poisoning (PSP) causing blooms of Alexandrium fundyense during late spring each year of the study. D. acuminata cell abundances were significantly correlated with levels of total phytoplankton biomass and Mesodinium spp., suggesting food web interactions may influence the dynamics of these blooms. Given that little is known regarding the combined effects of DSP and PSP toxins on human health and the concurrent accumulation and depuration of these toxins in shellfish, these blooms represent a novel managerial challenge.     

Semisolid media for isolation of Salmonella spp. from coastal waters

The use of two semisolid media (semisolid Rappaport and semisolid Rappaport-Vassiliadis) for the isolation of Salmonella spp. from coastal waters was compared with the use of conventional media. Two hundred and fifty six samples were studied; Salmonella spp. were detected in 83. The semisolid media were the most sensitive, detecting 73 samples instead of the 53 detected by the conventional media (P less than 0.001). The rate of isolation of Salmonella spp. showed an increase of 56.6% when the semisolid media were added to the conventional media, it being possible to detect 54.2% of the total organisms 1 day earlier.     

New Salmonella Serotype: Salmonella enteritidis ser. Ordonez

The antigenic formula of a new serotype, Salmonella enteritidis serotype Ordonez, was characterized as (1),13,23,37:y:l,w.     

Campylobacters and bacteriophages in the surface waters of Canterbury (New Zealand)

Aim:  To determine the relationship between the presence of thermotolerant campylobacters and their bacteriophages (phages) in surface waters for the potential to use phages as an indicator of Campylobacter spp.
Methods and Results:  Thermotolerant campylobacters were enumerated in 53 water samples using a three tube most probable number (MPN) series in m-Exeter broth. The presence of phages in the same samples was tested using two approaches: qualitative enrichment with five different Campylobacter hosts and a quantitative membrane concentration method. Phages infecting an Escherichia coli O157:H7 isolate were also enumerated by the membrane concentration method. Campylobacter spp. were isolated from 45/53 (85%) of the samples at 0.4–110 MPN 100 ml⁻¹. No Campylobacter phages were isolated, but coliphages were present in 43/46 (93%) of samples.
Conclusions:  The membrane concentration method recovered >80% of Campylobacter phages from spiked samples. The absence of Campylobacter phages in environmental samples, from both enrichment and concentration methods, suggests that, if present, they are at very low titres.
Significance and Impact of the Study:  Testing for Campylobacter phages as an indicator of Campylobacter spp. presence is not effective. The quantitative data for Campylobacter spp. will be useful for risk assessment purposes.     

Video plankton recorder reveals high abundances of colonial Radiolaria in surface waters of the central North Pacific

Colonial spumellarian Radiolaria are heterotrophic protiststhat form large (up to several meters in length), gelatinousstructures in the surface waters of all tropical and subtropicaloceanic ecosystems. These species are morphologically and trophicallycomplex and some, but not all, produce silica skeletal structuresof considerable paleontological significance. Skeletonless speciesof Radiolaria are poorly sampled by plankton nets, which canseverely damage these delicate organisms. Therefore, abundancesof colonial Radiolaria typically have been underestimated inquantitative studies of zooplankton abundance and biomass. Herewe document the abundances of colonial Radiolaria in the centralNorth Pacific based on analysis of video images from a miniaturizedvideo plankton recorder. We observed abundances of radiolariancells in colonies that exceeded previous reports of total Radiolariaby more than ten-fold, and counts of skeleton-bearing Radiolariaby more than two to three orders of magnitude. Biomass (carbon)within these colonies was similar to or greater than the totalradiolarian biomass (i.e. including all solitary species) previouslyreported for the Pacific. Symbiont productivity within colonialRadiolaria was estimated to constitute a modest but significantfraction of total primary productivity (up to     

Hedgerows as habitat corridors for forest herbs in central New York, USA

1 Samples from 32 hedgerows ( c.  6 m wide, with full-grown trees) in central New York included 39 forest herb taxa, comprising nearly 70% of the forest herb taxa found in adjacent forest samples.
2 We sampled three types of hedgerow. Two types were attached to forest: remnant hedgerows ( n  = 14), and regenerated hedgerows ( n  =  11 ) that had grown up spontaneously between open fields in the last 50 years. There were no significant differences between remnant and regenerated hedgerows in the richness or abundance of forest herbs, presumably indicating colonization of regenerated hedgerows. Such colonization implies that hedgerows serve a corridor function.
3 The species composition of forest herbs in hedgerows attached to forest stands showed a strong affinity with that of the adjacent stand, both for remnant and regenerated hedgerows.
4 There was a distance effect within hedgerows. Richness of forest herbs and similarity of composition to forest declined with distance along the hedgerow from forest, implying colonization from the adjacent attached stand.
5 The third type of hedgerow sampled, isolated remnants ( n  = 7), was not lower in richness or abundance of forest herbs than hedgerows attached to forest.     

Serrulacaulis furcatus gen. sp. nov., a New zosterophyll from the lower upper devonian of New York state

A new zosterophyll is described from the lower Upper Devonian of New York. Serrulacaulis furcatus is characterized by two rows of emergences which are opposite in arrangement and attached on opposite margins of the axis. They are deltoid in side view and are contiguous vertically, giving the stem a scalloped or saw-toothed appearance. Epidermis over much of the plant consists of elongate cells and interspersed isodiametric cells. The vascular strand consists of spirally thickened tracheids. Rhizomes are densely covered by rhizoids that are more numerous on small papillae and at the apex of tooth-like emergences. Aerial axes terminate in circinate apices. Some axes bear short-stalked, reniform sporangia arranged alternately in two rows on one side of the axis only. The dehiscence zone is a thickened rim over the distal, convex margin of the sporangium. Dehiscence is basipetal, producing two equal valves. Spores are smooth to slightly granulate, circular to subtriangular, with a trilete mark that extends $\text{1}\text{3}$–$\text{1}\text{2}$ the radius and is surrounded by a darkened triangular area. Sawdonia ornata, described earlier from the same quarry, and now Serrulacaulis, are the two genera of zosterophylls proven to occur in Late Devonian time. The world-wide distribution of zosterophylls and the fact that the group is a natural one are reviewed.     

Heterosigma akashiwo in central California waters

Heterosigma akashiwo (Hada) gives rise to red tides along the Atlantic and Pacific coasts and is known to produce brevetoxins. This investigation establishes baseline information showing the presence of H. akashiwo along the central California coast based on water samples collected from the Santa Cruz pier in Monterey Bay (on the open coast) and the Berkeley pier in San Francisco Bay. Light and electron microscopy as well as two species-specific DNA probe methods based on cell homogenates preparations were employed to detect H. akashiwo during the 2001–2002 field study. The DNA probe methods consisted of a sandwich hybridization assay (SHA), which targets ribosomal RNA (rRNA), and an end-point polymerase chain reaction (PCR) assay, which targets internal transcribed spacer (ITS) sequences of rRNA genes. The SHA was used to provide semi-quantitative data showing the intermittent presence of the species during a 13-month period in Monterey Bay. Samples that showed a variety of responses in the SHA (negative as well as the highest) were then subjected to the PCR assay in an attempt to confirm species identification using an independent DNA probe method that employs cell homogenates; samples included those from Monterey Bay and one from a red tide event in San Francisco Bay. SHA and PCR assays agreed on the presence or absence of H. akashiwo. Gene products from two field samples positive for H. akashiwo by PCR were cloned and sequenced and found to be identical to those of that species in GenBank. When the same samples were viewed by light microscopy, however, H. akashiwo cells were only seen in the sample with the highest abundance of that species, as evidenced by SHA. It was extremely difficult to recognize naturally occurring H. akashiwo using light microscopy in field samples that had been preserved with Lugol's iodine, including samples that gave positive results by cell homogenate methods. Results of this study indicate that H. akashiwo is present along the open California coast and could easily be missed in routine phytoplankton surveys. Despite its presence, H. akashiwo does not appear to routinely bloom with sufficient densities to cause harmful outbreaks of the frequency and severity documented in some other coastal environments. Molecular identification techniques may be the preferred approach over light microscopy when there is a need to rapidly screen many samples for fragile, harmful species and those that are otherwise problematic to identify based on their gross morphology alone.