Experimental pathogenicity of Vibrio parahaemolyticus for the schistosome-bearing snail Biomphalaria glabrata

1980 ◽  
Vol 26 (4) ◽  
pp. 503-506 ◽  
Author(s):  
Hugh W. Ducklow ◽  
Hector M. Tarraza Jr. ◽  
Ralph Mitchell
Keyword(s):  
Puerto Rican ◽  
Vibrio Parahaemolyticus ◽  
Trichloroacetic Acid ◽  
Sublethal Effects ◽  
Lethal Dose ◽  
Biomphalaria Glabrata ◽  
Wild Populations ◽  
Naturally Occurring ◽  
Experimental Pathogenicity ◽  
Significant Mortality

The bacterium Vibrio parahaemolyticus was found to be pathogenic for the schistosome intermediate host Biomphalaria glabrata (Say). When administered topically, a nonenteritis- associated strain of the bacterium had an LD50 (median lethal dose) of 6.8 × 107 cells per snail. A 5% trichloroacetic acid (TCA) extract from V. parahaemolyticus was found to kill B. glabrata. Sublethal effects of V. parahaemolyticus include shell deterioration and increased heart rate. Both albino aquarium populations and naturally occurring Puerto Rican wild populations of B. glabrata are susceptible to V. parahaemolyticus. This bacterium provides a useful model for the study of pathogens and biological control of schistosome vector snails, since it causes significant mortality and is recognized as a pathogen of other invertebrates.

scholarly journals Comparative Survival and the Cold-Induced Gene Expression of Pathogenic and Nonpathogenic Vibrio Parahaemolyticus from Tropical Eastern Oysters during Cold Storage

2020 ◽  
Vol 17 (6) ◽  
pp. 1836
Author(s):  
Francisco Alarcón Elvira ◽  
Violeta T. Pardío Sedas ◽  
David Martínez Herrera ◽  
Rodolfo Quintana Castro ◽  
Rosa María Oliart Ros ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Vibrio Parahaemolyticus ◽  
Cold Shock ◽  
Gene Expressions ◽  
Reverse Transcription Pcr ◽  
Naturally Occurring ◽  
Gene Response ◽  
Eastern Oysters ◽  
Kinetics Of

Expression of the regulatory stress rpoS gene controls the transcription of cspA genes, which are involved in survival and adaptation to low temperatures. The purpose of this study was to assess the growth kinetics of naturally occurring V. parahaemolyticus in shellstock oysters and in vitro and the cold-shock-induced expression of the rpoS and cspA gene response in vitro during postharvest refrigeration. Naturally contaminated eastern oysters (Crassostrea virginica) and pathogenic (Vp-tdh) and nonpathogenic (Vp-tlh) isolates were stored at 7 ± 1 °C for 168 h and 216 h, respectively. The regulatory stress (rpos) and cold-shock (cspA) gene expressions were determined by reverse transcription PCR. At 24 h, the (Vp-tdh) strain grew faster (p < 0.05) than the (Vp-tlh) strain in oysters (λ = 0.33, 0.39, respectively) and in vitro (λ = 0.89, 37.65, respectively), indicating a better adaptation to cold shock for the (Vp-tdh) strain in live oysters and in vitro. At 24 h, the (Vp-tdh) strain rpoS and cspA gene expressions were upregulated by 1.9 and 2.3-fold, respectively, but the (Vp-tlh) strain rpoS and cspA gene expressions were repressed and upregulated by −0.024 and 1.9-fold, respectively. The V. parahaemolyticus strains that were isolated from tropical oysters have adaptive expression changes to survive and grow at 7 °C, according to their virulence.

scholarly journals Strain variation in the infectivity of Schistosoma mansoni for Biomphalaria glabrata

1988 ◽  
Vol 30 (2) ◽  
pp. 86-90 ◽  
Author(s):  
Luiz Candido de Souza Dias ◽  
John I. Bruce ◽  
Gerald C. Coles
Keyword(s):  
Schistosoma Mansoni ◽  
Puerto Rican ◽  
Biomphalaria Glabrata ◽  
The Other ◽  
Drug Resistant ◽  
Strain Variation ◽  
Resistant Strains ◽  
Drug Resistant Strains

Five strains of Schistosoma mansoni resistant and susceptible to schistosomicides were studied for infectivity of 2 strains of Biomphalaria glabrata one of Puerto Rican origin and the other of Brazilian origin. Puerto Rican strains of S. Mansoni developed more slowly and had a lower infectivity in Brazilian B. glabrata than did the Brazilian S. mansoni. However, Brazilian S. Mansoni developed as well in Puerto Rican snails as in Brazilian snails, indicating that drug resistant strains could easily be moved by travel of infected persons from one area to another.

Effect of Ploidy on Vibrio parahaemolyticus and Vibrio vulnificus Levels in Cultured Oysters

2020 ◽  
Vol 83 (11) ◽  
pp. 2014-2017
Author(s):  
JESSICA L. JONES ◽  
KERI A. LYDON ◽  
WILLIAM C. WALTON
Keyword(s):  
Crassostrea Virginica ◽  
Vibrio Parahaemolyticus ◽  
Pathogenic Bacteria ◽  
Vibrio Vulnificus ◽  
High Quality ◽  
Colony Hybridization ◽  
Naturally Occurring ◽  
Rapid Growth Rate ◽  
Vibrio Spp ◽  
Half Sibling

ABSTRACT Vibrio parahaemolyticus and Vibrio vulnificus are naturally occurring human pathogenic bacteria commonly found in estuarine environments where oysters are cultured. The use of triploid oysters has increased due to their rapid growth rate and because they maintain a high quality throughout the year. Previous work suggested levels of Vibrio spp. may be lower in triploid oysters than diploid oysters. Therefore, this study aimed to determine whether there is a difference in the abundances of V. parahaemolyticus and V. vulnificus between half-sibling diploid and triploid American oysters (Crassostrea virginica). In four trials, 100 individual oysters (either iced or temperature abused) were analyzed for V. parahaemolyticus and V. vulnificus by using direct plating followed by colony hybridization. Mean levels of V. parahaemolyticus in iced and abused diploid oysters were 3.55 and 4.21 log CFU/g, respectively. Mean levels in iced and abused triploid oysters were 3.49 and 4.27 log CFU/g, respectively. Mean levels of V. vulnificus in iced and abused diploid oysters were 3.53 and 4.56 log CFU/g, respectively. Mean levels in iced and abused triploid oysters were 3.54 and 4.55 log CFU/g, respectively. The differences in Vibrio spp. abundances between diploid and triploid oysters was not significant (P &gt; 0.05). However, the differences across treatments were significant (P &lt; 0.05), with the exception of V. parahaemolyticus levels in trial 3 (P = 0.83). Variation between individual oysters was also observed, with 12 of 808 measurements being outside of the 95th percentile. This phenomenon of occasional statistical outliers (“hot” or “cold” oysters) has been previously described and supports the appropriateness of composite sampling to account for inherent animal variability. In summary, the data indicate that abundances of V. parahaemolyticus and V. vulnificus are not dependent on the ploidy of cultured oysters but vary with the type of handling. HIGHLIGHTS

scholarly journals Concurrent Quantitation of Total Campylobacter and Total Ciprofloxacin-Resistant Campylobacter Loads in Rinses from Retail Raw Chicken Carcasses from 2001 to 2003 by Direct Plating at 42°C

2005 ◽  
Vol 71 (8) ◽  
pp. 4510-4515 ◽  
Author(s):  
Ramakrishna Nannapaneni ◽  
Robert Story ◽  
Keith C. Wiggins ◽  
Michael G. Johnson
Keyword(s):  
Detection Limit ◽  
Agar Medium ◽  
Lethal Dose ◽  
Sampling Period ◽  
Selective Isolation ◽  
Direct Plating ◽  
First Report ◽  
Naturally Occurring

ABSTRACT This is the first report on the use of a normally lethal dose of ciprofloxacin in a Campylobacter agar medium to kill all ciprofloxacin-sensitive Campylobacter spp. but allow the selective isolation and quantitation of naturally occurring presumptive ciprofloxacin-resistant Campylobacter CFU in rinses from retail raw chicken carcasses (RTCC). Thermophilic-group total Campylobacter CFU and total ciprofloxacin-resistant Campylobacter CFU (irrespective of species) were concurrently quantified in rinses from RTCC by direct plating of centrifuged pellets from 10 or 50 ml out of 400-ml rinse subsamples concurrently on Campylobacter agar and ciprofloxacin-containing Campylobacter agar at 42°C (detection limit = 0.90 log10 CFU/carcass). For 2001, 2002, and 2003, countable Campylobacter CFU were recovered from 85%, 96%, and 57% of RTCC, while countable ciprofloxacin-resistant Campylobacter CFU were recovered from 60%, 59%, and 17.5% of RTCC, respectively. Total Campylobacter CFU loads in RTCC rinses ranged from 0.90 to 4.52, 0.90 to 4.58, and 0.90 to 4.48 log10 CFU/carcass in 2001, 2002, and 2003, respectively. Total ciprofloxacin-resistant Campylobacter CFU loads in RTCC rinses ranged from 0.90 to 4.06, 0.90 to 3.95, and 0.90 to 3.04 log10 CFU/carcass in 2001, 2002, and 2003, respectively. Overall, total Campylobacter loads of 0.90 to 2.0, 2 to 3, 3 to 4, 4 to 5 log10 CFU/carcass, respectively, were recovered from 16%, 32%, 26%, and 5% of RTCC tested over the 2-year sampling period. For the same period, total ciprofloxacin-resistant Campylobacter loads of 0.90 to 2.0, 2 to 3, 3 to 4, and 4 to 5 log10 CFU/carcass, respectively, were recovered from 24%, 11%, 7%, and 0.2% of RTCC tested. There was a steady decline in total Campylobacter and total ciprofloxacin-resistant Campylobacter loads in RTCC rinses from 2001/2002 to 2003.

Populations of Vibrio parahaemolyticus in Retail Oysters from Florida Using Two Methods

2001 ◽  
Vol 64 (5) ◽  
pp. 682-686 ◽  
Author(s):  
ROBIN K. ELLISON ◽  
ERIKA MALNATI ◽  
ANGELO DePAOLA ◽  
JOHN BOWERS ◽  
GARY E. RODRICK
Keyword(s):  
Alkaline Phosphatase ◽  
Vibrio Parahaemolyticus ◽  
Geometric Mean ◽  
Environmental Distribution ◽  
Direct Plating ◽  
Naturally Occurring ◽  
Biochemical Identification ◽  
Stressed Cells ◽  
Species Specific ◽  
Identification Techniques

Vibrio parahaemolyticusis a naturally occurring estuarine bacterium that is often associated with gastroenteritisin humans following consumption of raw molluscan shellfish. A number of studies have investigated the environmental distribution of V. parahaemolyticus, but little is known about the levels of this organism during distribution of oysters or at the point of consumption. Duplicate samples of shellstock oysters were collected monthly (September 1997 to May 1998) from the same four restaurants and three wholesale seafood markets in the Gainesville, Fla. area and analyzed for total V. parahaemolyticus densities using two methods: a standard MPN method (BAM-MPN) and a new direct plating procedure (direct-VPAP). Both methods employed an alkaline phosphatase-labeled DNA probe (VPAP) targeting the species-specific thermolabile hemolysin (tlh) gene to confirm suspect colonies as V. parahaemolyticus. The highest monthly geometric mean V. parahaemolyticus density was observed in October of 1997 (~3,000/g) with similarly high values during September and November of 1997. From December 1997 to May 1998 mean densities were generally less than 100/g, falling to ~10/g in February and March. A strong correlation (r = 0.78) between the direct-VPAP and BAM-MPN methods for determining V. parahaemolyticus densities in market-level oysters was observed. The direct-VPAP method was more rapid and precise while the BAM-MPN was more sensitive and may better recover stressed cells. The utilization of the VPAP probe for identification of V. parahaemolyticus sharply reduced the labor for either method compared to biochemical identification techniques used in earlier V. parahaemolyticus surveys.

scholarly journals Selection at 6-PGD locus in laboratory populations of Bactrocera oleae

2008 ◽  
Vol 90 (5) ◽  
pp. 379-384
Author(s):  
NIKOS COSMIDIS ◽  
GEORGE GOULIELMOS ◽  
ELIAS ELIOPOULOS ◽  
MICHAEL LOUKAS
Keyword(s):  
Selection Pressure ◽  
Selective Pressure ◽  
Bactrocera Oleae ◽  
Missense Mutations ◽  
Wild Populations ◽  
Phosphogluconate Dehydrogenase ◽  
Naturally Occurring ◽  
Laboratory Populations ◽  
Set Up ◽  
New Evidence

SummaryWe have previously shown that laboratory populations of the olive fruitfly Bactrocera oleae come to equilibrium with allele frequencies at the 6-phosphogluconate dehydrogenase (6-PGD) locus markedly different from those of wild populations. In this study, we present new evidence from perturbation experiments in support of the notion that the locus is under selective pressure under laboratory conditions. Eleven populations were started with frequencies at the 6-PGD locus different from the laboratory equilibrium. Over 12 generations, the populations showed a return to the previous equilibrium, indicating a direct and powerful selection pressure on the naturally occurring allozymes of this locus. That is, a marked increase of the F allele followed by a compensatory decrease of allele I. Populations were set up to minimize the effects of associative overdominance, and we discuss the possible influence of this factor. Nucleotide sequence for the 6-PGD F and I alleles revealed two missense mutations at positions 501 and 730 leading to different amino acids among the two alleles.

Simplified Purification and Biophysicochemical Characteristics of Kanagawa Phenomenon-Associated Hemolysin of Vibrio parahaemolyticus

1980 ◽  
Vol 28 (2) ◽  
pp. 567-576
Author(s):  
Yasushi Miyamoto ◽  
Yasushi Obara ◽  
Takayasu Nikkawa ◽  
Shiro Yamai ◽  
Teiji Kato ◽  
...  
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Culture Supernatant ◽  
Lethal Dose ◽  
Apparent Molecular Weight ◽  
Experimental Models ◽  
Factor Activity ◽  
Ileal Loop ◽  
Heat Stable ◽  
Ion Exchange Column ◽  
Structural Disturbances

Kanagawa phenomenon-associated hemolysin (K-hemolysin) was purified by Sephadex gel and ion-exchange column chromatography, after the culture supernatant had been adsorbed on and eluted from diethylaminoethyl-Sepharose CL-6B, and acid precipitated. K-hemolysin was a heat-stable and trypsin-susceptible protein with an apparent molecular weight of 44,000, the subunit of which was 22,000. The isoelectric point was 4.9. The minimum hemolytic dose was 0.1 μg/ml. The fifty percent lethal dose by intravenous injection was 1.4 μg. Electron microscopy of the small intestine of suckling mice orally challenged with the highest dose (50 μg) not only showed disappearance of epithelial cell microvilli, but also structural disturbances of the endoplasmic reticulum and mitochondrial swelling. One blueing dose representing permeability factor activity was 0.3 μg, and positive reaction in the rabbit ileal loop appeared at above 125 μg. Besides these data in experimental models, we discovered the appearance of an antibody in patients which neutralizes K-hemolysin during the course of the disease. This finding reinforces our view that K-hemolysin plays a most significant role in the pathogenesis of this enteric human disease.

scholarly journals Acuteβ-N-Methylamino-L-alanine Toxicity in a Mouse Model

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Maitham Ahmed Al-Sammak ◽  
Douglas G. Rogers ◽  
Kyle D. Hoagland
Keyword(s):  
Adverse Effect ◽  
Lethal Dose ◽  
Naturally Occurring ◽  
Adverse Effect Level ◽  
Effect Level ◽  
Outbred Mice ◽  
Nih Swiss ◽  
And Control ◽  
Lateral Sclerosis

The cyanobacterial neurotoxinβ-N-methylamino-L-alanine (BMAA) is considered to be an “excitotoxin,” and its suggested mechanism of action is killing neurons. Long-term exposure to L-BMAA is believed to lead to neurodegenerative diseases including Parkinson’s and Alzheimer’s diseases and amyotrophic lateral sclerosis (Lou Gehrig’s disease). Objectives of this study were to determine the presumptive median lethal dose (LD50), the Lowest-Observed-Adverse-Effect Level (LOAEL), and histopathologic lesions caused by the naturally occurring BMAA isomer, L-BMAA, in mice. Seventy NIH Swiss Outbred mice (35 male and 35 female) were used. Treatment group mice were injected intraperitoneally with 0.03, 0.3, 1, 2, and 3 mg/g body weight L-BMAA, respectively, and control mice were sham-injected. The presumptive LD50of L-BMAA was 3 mg/g BW and the LOAEL was 2 mg/g BW. There were no histopathologic lesions in brain, liver, heart, kidney, lung, or spleen in any of the mice during the 14-day study. L-BMAA was detected in brains and livers in all of treated mice but not in control mice. Males injected with 0.03 mg/g BW, 0.3 mg/g BW, and 3.0 mg/g BW L-BMAA showed consistently higher concentrations (P< 0.01) in brain and liver samples as compared to females in those respective groups.

FROST DAMAGE IN FLOWERS AND IMMATURE FRUITS OF Amelanchier alnifolia NUTT. (MALOIDEAE)

1983 ◽  
Vol 63 (2) ◽  
pp. 461-466 ◽  
Author(s):  
A. RANDALL OLSON ◽  
TAYLOR A. STEEVES
Keyword(s):  
Ovarian Tissue ◽  
Frost Damage ◽  
Wild Populations ◽  
Amelanchier Alnifolia ◽  
Inferior Ovary ◽  
Tissue Degeneration ◽  
Naturally Occurring ◽  
Histological Damage ◽  
Frost Injury ◽  
Spring Frosts

Flower buds, blossoms, and immature fruits from wild populations of Amelanchier alnifolia Nutt. (Maloideae) were examined for histological damage resulting from naturally occurring spring frosts. Floral tissues become vulnerable to frost injury at anthesis. Tissue degeneration appears to be restricted to what has been interpreted as carpel in the typical pomoid, inferior ovary. An understanding of certain phenological and ovarian tissue susceptibilities may contribute to the evaluation of new cultivars with the potential for circumventing the threat of cold injury.Key words: Fruit, carpel, inferior ovary, Amelanchier alnifolia

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