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L J Albright

Publications and source records attributed to L J Albright.

At least 19 recordsLinked to original sources
PubMed2000

Characterization of a virus obtained from snakeheads Ophicephalus striatus with epizootic ulcerative syndrome (EUS) in the Philippines.

This is the first report of the isolation and characterization of a fish virus from the Philippines. The virus was isolated using snakehead spleen cells (SHS) from severely lesioned epizootic ulcerative syndrome (EUS)-affected snakehead Ophicephalus striatus from Laguna de Bay, in January 1991. The virus induced cytopathic effects (CPE) in SHS cells yielding a titer of 3.02 x 10(6) TCID50 ml(-1) at 25 degrees C within 2 to 3 d. Other susceptible cell lines included bluegill fry (BF-2), catfish spleen (CFS) and channel catfish ovary (CCO) cells. Replication in chinook salmon embryo cells (CHSE-214) was minimal while Epithelioma papulosum cyprini cells (EPC) and rainbow trout gonad cells (RTG-2) were refractory. Temperatures of 15 to 25 degrees C were optimum for virus replication but the virus did not replicate at 37 degrees C. The virus can be stored at -10 and 8 degrees C for 30 and 10 d, respectively, without significant loss of infectivity. Viral replication was logarithmic with a 2 h lag phase; viral assembly in the host cells occurred in 4 h and release of virus occurred 8 h after viral infection. A 1-log difference in TCID50 titer between the cell-free virus and the total virus was noted. Freezing and thawing the virus caused a half-log drop in titer. Viral exposure to chloroform or heating to 56 degrees C for 30 min inactivated the virus. Exposure to pH 3 medium for 30 min resulted in a more than 100-fold loss of viral infectivity. The 5-iododeoxyuridine (IUdR) did not affect virus replication, indicating a RNA genome. Neutralization tests using the Philippine virus, the ulcerative disease rhabdovirus (UDRV) and the infectious hematopoietic necrosis virus (IHNV) polyvalent antisera showed slight cross-reaction between the Philippine virus antiserum and UDRV but established no serological relationship with SHRV and IHN virus. Transmission electron microscopy (TEM) of SHS cells infected with the virus showed virus particles with typical bullet morphology and an estimated size of 65 x 175 nm. The Philippine virus was therefore a rhabdovirus, but the present study did not establish its role in the epizootiology of EUS.

Animals↗
PubMed1987

Annual cycle of bacterial specific biovolumes in howe sound, a canadian west coast fjord sound.

The mean specific biovolumes (biovolume cell) of the bacterioplankton within a 250-m-deep water column in Howe Sound, British Columbia, were determined for the period of 4 September 1984 to 23 October 1985. These bacteria had an annual cycle in mean specific biovolume; they were small (ca. 0.058 mum) in mid-winter, larger in spring (ca. 0.076 mum), larger again in summer (up to 0.102 mum), and largest (ca. 0.133 mum) in early fall (immediately after the decrease in phytoplankton production). The mean specific biovolumes changed coincidently through the water column with time, although the larger bacterioplankton tended to occur in the surface and deepest water. Although the mean specific biovolumes correlated better with in situ temperature (r = 0.65, a = 0.01) than with in situ chlorophyll a concentration (r = 0.34, a = 0.25), modeling experiments with batch cultures of the dinoflagellate Prorocentrum minimum (Pavillard) and the green alga Dunaliella tertiolecta (Butcher) indicated that the biomass and physiological condition of the phytoplankters may be more important than temperature in determining these bacterial specific biovolumes.

Journal Article↗
PubMed1987

Annual bacterioplankton biomasses and productivities in a temperate west coast canadian fjord.

Bacterioplankton numbers, biomasses, and productivities, as well as chlorophyll a concentrations and phytoplankton productivities, were assayed from 1 March 1984 to 12 August 1985 through a 250-m-deep seawater column in Howe Sound, a temperate fjord-sound on the southern coast of British Columbia, Canada. Primary production during this 18-month period was 845 g of C m. Bacterial production was assayed over this same period as 193 g of C m (thymidine incorporation) and 77 g of C m (frequency of dividing cells). Bacterial productivities per cubic meter were usually greater in the euphotic zone than in deeper aphotic water, but when integrated through the water column, approximately half of the bacterial production occurred in the deeper aphotic portion. Bacterial production occurred throughout the year, although at reduced rates in late fall and early winter; primary production almost ceased during late fall and early winter. Because of this heterotrophic bacterioplankton production was a very large portion of the microbial (bacterial plus phyto-plankton) production at this time. In mid-summer bacterial production was a small proportion of the microbial production. Because of this asynchrony in peaks and troughs of bacterial and phytoplankton production through the year, data comparison is best done over an annual cycle. On this basis the bacterial production in the Howe Sound water column was between 23 and 9% of the phytoplankton production when a bacterial C to biovolume ratio of 0.107 pg of C mum was assumed; the corresponding values were 64 and 29% when a ratio of 0.300 pg of bacterial C mum was assumed.

Journal Article↗
PubMed1986

Attached and free-floating bacterioplankton in howe sound, british columbia, a coastal marine fjord-embayment.

Factors which influence the attachment of bacterioplankton to particles (including phytoplankton) were investigated by using (i) water samples removed from a coastal temperate fjord over an annual cycle and (ii) unialgal cultures of Prorocentrum minimum, Dunaliella tertiolecta, and Skeletonema costatum. Silt and salinity levels in this fjord seawater did not appear to influence bacterial attachment, but the percent attached bacteria was inversely related to both chlorophyll a concentrations and primary productivities. During periods of high primary productivities the percent attached bacteria was low, whereas during periods of low, increasing, and declining primary productivities the percent attached bacteria was high. A similar pattern of bacterial attachment was observed when the three phytoplankton were grown as batch cultures. The percent attached bacterial numbers increased upon the initiation of algal growth and after these cells stopped growing, but not while the algae were growing. We suggest that a major factor influencing the attachment of bacterioplankton is the physiological condition of their major nutrient source, the phytoplankton; mainly free-living bacteria are associated with growing phytoplankton, whereas a much greater proportion of the bacteria are attached among senescent phytoplankton populations.

Journal Article↗
PubMed1984

The effects of the insecticide acephate on the growth and nutrient uptake of an aquatic bacterium.

The effects of high (1000 ppm) and low (1 ppm) concentrations of acephate on the rate of growth and nutrient uptake by an aquatic bacterium (identified as Chromobacterium lividum ) were investigated. This insecticide increased doubling time, decreased maximum cellular yield, and reduced cell size when C. lividum was grown in the presence of high acephate concentrations. Total [14C]glucose and 14C-labeled amino acids uptake rates were reduced by the high acephate concentration. The high acephate concentration did not affect active uptake of [14C]cycloleucine, a nonmetabolized amino acid analogue. Low concentration of acephate had little apparent influence upon these metabolic processes.

Amino Acids↗
PubMed1982

Attached and free-floating bacteria in a diverse selection of water bodies.

The contribution of attached and free-floating bacteria to the bacterial numbers and heterotrophic uptake in 44 diverse aquatic environments was studied. A factor analysis reduced the variability of the raw data base to three major factors explaining 53.6% of total variance. These factors were (i) salinity, (ii) heterotrophic uptake, and (iii) particulate load. A cluster analysis categorized the 44 habitats into five distinct environmental types based on these three factors. There was no significant pattern in the distribution of attached versus free-floating bacteria when assessed by epifluorescent microscopy. However the contribution of attached bacteria to the uptake of an amino acids mix was reduced in marine waters. Heavy particulate loads resulted in an increased percentage uptake of amino acids and glucose from the attached bacteria. Uptake response was found to be substrate specific especially in oliogotrophic freshwater. Amino acid uptake was more associated with the attached fraction, whereas glucose uptake was mediated more by the free-floating fraction.

Journal Article↗
PubMed1981

Heterotrophic activities of bacterioplankton and bacteriobenthos.

Several marine waters and surface sediments of coastal British Columbia were analyzed and compared for bacterial colony forming units (CFU) and numbers of active bacteria (NAB) as indicated by microautoradiography, glucose and alanine heterotrophic activities, and dissolved (DOC) and particulate organic carbon (POC). Bacteria numbers (CFU, NAB) were usually much greater (by several orders of magnitude) in surface sediments than in overlying waters. DOC and POC were also generally greater in surface sediments than in overlying waters, often by as much as one order of magnitude. Both glucose and alanine heterotrophic potentials were greater in surface sediments; however, on a per active cell (NAB) basis, no significant differences were noted between the glucose-specific activities of the bacteria of the surface sediments and overlying waters. The data suggest that these surface sediments carry greater standing crops of bacteria than overlying waters without significant decreases in glucose-specific activities.

Alanine↗
PubMed1980

Residues in cutthroat trout (Salmo clarki) and California newts (Tarichia torosa) from a lake treated with technical chlordane.

The water of a lake was sprayed with technical chlordane to give a concentration of approximately 10 ppb. Resident California newts (Tarichia torosa) and cutthroat trout (Salmo clarki) were subsequently collected and analyzed for residue concentrations. The newts were collected at 14, 279, 451, and 1,036 days; the trout at 93, 279, 421, and 1,014 days. At first, the concentrations of residues were very high in both species and their composition, except for heptachlor, resembled that of technical chlordane. The heptachlor was quantitatively epoxidized in news after 14 days but in trout, some heptachlor was still present after 93 days. Concentrations of total chlordane in body tissues of both species declined more than 98% with time. Of seven individually determined constituents of technical chlordane, trans-nonachlor was by far the most persistent, accounting for 49 to 55% of total chlordane in specimens collected last. Both animals produced oxychlordane, probably from gamma-chlordane. Heptachlor, heptachlor epoxide and gamma-chlordeine were non-detectable in both species after 279 days. The results strongly suggest that the California newt metabolizes and eliminates chlordane residues more effectively than the cutthroat trout.

Animals↗
PubMed1980

Photosynthetic activities of phytoneuston and phytoplankton.

Numbers, biomasses, and photosynthetic activities of phytoneuston and phytoplankton of near-surface microlayer and associated sub-surface waters, respectively, of coastal British Columbia were compared. Microalgal numbers, biomasses, and photosynthetic activities were generally greater in the sub-surface waters. Photosynthetic activities per unit biomass of the phytoneuston were approximately two-thirds those of the phytoplankton. These data suggest that the phytoneuston are injured or inhibited in some manner in near-surface microlayer waters.

British Columbia↗
PubMed1978

Hydrostatic pressure effects upon cellular leakage and active transport by Vibrio marinus.

Hydrostatic pressures greater than ca. 400 atm cause release of cellular components of Vibrio marinus MP-1 in the order protein greater than RNA greater than malate dehydrogenase greater than DNA greater than amino acids. Increased pressures also slow the rate of cycloleucine (non-metabolizable analogue of L-leucine acid L-valine) uptake but increase its efflux rate. Lineweaver-Burk plots (1/V versus 1/[S]) of cycloleucine uptake indicate that the Km increases with compression which suggests a decrease in affinity of the transport system for substrate at increased pressures.

Amino Acids↗
PubMed1978

Persistence of residues in water and sediment of a fresh-water lake after surface application of technical chlordane.

A fresh-water lake, free from detectable pesticide residues before this study, was treated with a commercial formulation of technical chlordane. Water and sediment samples were analysed for chlordane residues 7, 24, 52, 279. and 421 days after treatment. Residues moved rapidly from the water to the lake bottom, supporting earlier results of a laboratory study with other organochlorines. In water, alpha- and gamma-chlordane concentrations remained proportional to total chlordane concentrations, as determined by total-peak area measurements of gas-liquid chromatogrammes. But in bottom sediments, alpha- and gamma-chlordane were more persistent than other constituents of technical chlordane, supporting recent evidence that quantification of technical chlordane residues on the basis of gamma-chlordane quantification only (or that of alpha- and gamma-chlordane only), can lead to incorrect results and that this method, although simple and fast, should no longer be recommended.

British Columbia↗
PubMed1978

Respiration correction for microbial heterotrophic activity assays that use tritium-labeled substrates.

Filtrates from microbial heterotrophic activity assay experiments in which tritiated glucose was used as a radioactively labeled substrate were collected, and their radioactivities were determined. These filtrates were subsequently evaporated to dryness to remove tritiated water generated by metabolism of the labeled glucose; the residue was suspended to original volume with distilled water, and the tritium levels were again assayed. In the water samples assayed, the amount of tritium label retained by the microorganism was about 75% of that respired.

Journal Article↗
PubMed1977

Alternative model and approach for determining microbial heterotrophic activities in aquatic systems.

Increasing amounts of high-specific-activity tritiated organic compounds were added to samples of several natural waters such that in situ substrate concentrations might be approximated. The uptake responses by the native heterotrophic microflora suggested that (i) heterotrophic populations metabolize the added nutrients, but (ii) these responses are not necessarily a reflection of Michaelis-Menten enzyme kinetics. The uptake kinetics appeared to be due to dilution of the naturally occurring metabolite by added radioactive substrate and physiological responses of the microflora to organic enrichment.

Amino Acids↗
PubMed1976

Heterotrophic activities of bacterioneuston and bacterioplankton.

Numbers of viable bacteria as indicated by colony-forming units (CFU), microbial adenosine triphosphate levels, dissolved organic carbon (DOC), particulate organic carbon and nitrogen (POC and PON), glucose concentration, heterotrophic potential (Vmax), and in situ heterotrophic activity (Vn) of near-surface microlayer samples (70-80 mum depth), the neuston, and bulk column water samples (0.2-1.5 m depth), the plankton, of several natural waters were compared. DOC and glucose concentration values of near-surface and bulk water were similar, whereas POC and PON values of the near-surface were normally one order of magnitude greater than those of bulk water. Viable counts were generally greater in the neuston, but ATP levels were greater in the plankton. Comparative values of total heterotrophic potentials and heterotrophic activities fluctuated greatly. Heterotrophic potential per CFU of the neuston was 33% of that of the plankton; neuston heterotrophic activity per CFU was 10% of that of the plankton. These data suggest that neustonic heterotrophic bacteria are not as metabolically active as their planktonic counterparts and that they are under greater stress at the near-surface than in the column water.

Adenosine Triphosphate↗
PubMed1975

Chlorinated hydrocarbon residues in fish, crabs, and shellfish of the Lower Fraser River, its estuary, and selected locations in Georgia Strait, British Columbia--1972-73.

Between August 1972 and September 1973, fish, crabs, and shellfish were collected from the lower Fraser River, its estuary, and selected areas of Georgia Strait in British Columbia. Samples were analyzed for aldrin, dieldrin, alpha- and gamma-chlordane, p,p'-DDT, p,p'-DDE, p,p'-DDD, heptachlor, heptachlor epoxide, lindane, and polychlorinated biphenyls (PCB's). Of these, p,p'-DDT, p,p'-DDE, p,p'-DDD, heptachlor epoxide, and one PCB, Aroclor 1254, were detected in samples of many fish, crabs, and shellfish from the lower Fraser River and its estuary. Generally, compounds found in decreasing order of magnitude in samples from the Fraser River and its estuary were: PCB's, p,p'-DDE, heptachlor epoxide, p,p'-DDT, and p,p'-DDD. Greatest concentrations of these compounds occurred in biota from the waters adjacent to the City of Vancouver. With one exception, animals from Georgia Strait and those away from the immediate influence of Fraser River water contained no detectable levels of chlorinated hydrocarbons.

Animals↗