Quantitative and Qualitative Studies of Bacteria Isolated from Sea Water Used in the Laboratory Culture of the American Oyster, Crassostrea virginica

1975 ◽  
Vol 32 (6) ◽  
pp. 739-745 ◽  
Author(s):  
R. A. Murchelano ◽  
C. Brown ◽  
J. Bishop
Keyword(s):  
Ultraviolet Light ◽  
Crassostrea Virginica ◽  
Storage Tank ◽  
Sea Water ◽  
Sampling Period ◽  
Laboratory Culture ◽  
Qualitative Studies ◽  
American Oyster ◽  
The Mean ◽  
Number Of Bacteria

Quantitative and qualitative bacteriological studies were conducted on sea water utilized in laboratory culture of American oyster larvae (Crassostrea virginica).The generic diversity of bacteria isolated from a laboratory seawater storage tank did not change during a 15-day sampling period, although bacterial numbers increased substantially. The mean number of bacteria in ultraviolet light-irradiated sea water was less than that in nonirradiated sea water, although individual samples varied considerably. Over a 10-day sampling period during which oyster larval cultures were sampled repetitively, bacteria were more numerous at 24 h and 48 h than at 0 h.Pseudomonas was the dominant genus present in stored sea water, irradiated sea water, and sea water from oyster larval cultures.

Organophosphorus insecticide resistance in a new strain of Culex quinquefasciatus (Diptera: Culicidae) from Tanga, Tanzania

1993 ◽  
Vol 83 (1) ◽  
pp. 67-74 ◽  
Author(s):  
A. Khayrandish ◽  
R.J. Wood
Keyword(s):  
Insecticide Resistance ◽  
Culex Quinquefasciatus ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Laboratory Culture ◽  
Fourth Instar ◽  
Resistance Allele ◽  
Susceptible Control ◽  
The Mean

AbstractFourth instar larvae of a new strain of Culex quinquefasciatus Say from Tanzania (TANGA) were tested for insecticide resistance. Initially, the resistance ratio (RR) to chlorpyrifos was 41.8, to temephos 30.8, to propoxur 3.7. After 2–3 years of laboratory culture, resistance to chlorpyrifos and propoxur had declined (chlorpyrifos 5.7, 3.8; propoxur 1.9, permethrin 1.9). Significant synergism was found between s, s, s-tributyl trithiophosphate (DEF) and chlorphyrifos, reducing the RR from 8.0 to 2.5. Synergism between piperonyl butoxide and permethrin was less than in a susceptible control strain. Twelve esterase isozymes of different relative mobilities (Rm) on polyacrylamide gel electrophoresis were identified, ten of which remained when the strain was reinvestigated two years (approximately 32 generations) later. Null activity for all but one of these bands was observed in some larvae. Four esterase bands (Rm 0.25, 0.27, 0.31, 0.34, designated A2, A3, B2, B3) showed polymorphism in activity, with very intense bands in some larvae. The mean frequency of bands with activity greater than standard, declined as organophosphorus (OP) resistance declined, but resistance was unconnected with the frequency of nulls at these positions. In mass larval assays of in vitro sensitivity of acetylcholinesterase (AChE) to propoxur, the I50 exceeded 10x10−4M, compared with 0.1x10−4M in a reverted resistant strain (RANGOON). Single larvel assays revealed heterogeneity, which was interpreted on the basis of an AChE resistance allele (AceR) with a frequency of 0.23.

scholarly journals Quantitation of Bacteria in Blood of Typhoid Fever Patients and Relationship between Counts and Clinical Features, Transmissibility, and Antibiotic Resistance

1998 ◽  
Vol 36 (6) ◽  
pp. 1683-1687 ◽  
Author(s):  
John Wain ◽  
To Song Diep ◽  
Vo Anh Ho ◽  
Amanda M. Walsh ◽  
Nguyen Thi Tuyet Hoa ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Salmonella Typhi ◽  
Multidrug Resistant ◽  
Buffy Coat ◽  
Broth Culture ◽  
Bacterial Counts ◽  
Duration Of Illness ◽  
The Mean ◽  
Independent Association ◽  
Number Of Bacteria

Salmonella typhi was isolated from 369 andSalmonella paratyphi A was isolated from 6 of 515 Vietnamese patients with suspected enteric fever. Compared with conventional broth culture of blood, direct plating of the buffy coat had a diagnostic sensitivity of 99.5% (95% confidence interval [CI], 97.1 to 100%). Blood bacterial counts were estimated by the pour plate method. The median S. typhi count in blood was 1 CFU/ml (range, <0.3 to 387 CFU/ml), of which a mean of 63% (95% CI, 58 to 67%) were intracellular. The mean number of bacteria per infected leukocyte was 1.3 (interquartile range [IQR], 0.7 to 2.4) CFU/cell (n = 81). Children (<15 years old;n = 115) had higher median blood bacterial counts than adults (n = 262): 1.5 (range, <0.3 to 387) versus 0.6 (range, <0.3 to 17.7) CFU/ml (P = 0.008), and patients who excreted S. typhi in feces had higher bacteremias than those who did not: a median of 3 (range, <0.3 to 32) versus 1 (range, <0.3 to 68) CFU/ml (P = 0.02). Blood bacterial counts declined with increasing duration of illness (P = 0.002) and were higher in infections caused by multidrug-resistant S. typhi (1.3 [range, <0.3 to 387] CFU/ml; n = 313) than in infections caused by antibiotic-sensitive S. typhi (0.5 [range, <0.3 to 32] CFU/ml; n = 62) (P = 0.006). In a multivariate analysis this proved to be an independent association, suggesting a relationship between antibiotic resistance and virulence in S. typhi.

scholarly journals Analysis and Development of Seawater Density Measurement Algorithms Using Arduino Uno and YL-69 Sensor

2020 ◽  
Vol 4 (5) ◽  
pp. 951-956
Author(s):  
Miftahul Walid ◽  
Hozairi ◽  
Madukil Makruf
Keyword(s):  
Sea Water ◽  
Density Measurement ◽  
Absolute Error ◽  
Error Level ◽  
Value Range ◽  
Density Values ◽  
The Mean ◽  
Arduino Uno ◽  
The Difference ◽  
Predicted Values

In this research, an analysis was carried out to develop a measuring instrument for seawater density in salt production using a microcontroller (Arduino Uno) and YL-69 sensor, this sensor was commonly used to measure soil moisture. The experimental method was used in this research to produce initial data in the form of resistance and seawater density values, then calculations are carried out using statistical methods to find equations and produce a constant variable that connects the resistance and seawater density values. The equation was used to compile the algorithm into Arduino Uno. As for the results of this research,  From six experiments conducted, two experiments produced the same sea water density value between the actual and the predicted, namely the 2nd and 5th experiments, while for other experiments there was a difference between the actual and predicted values, however, it was not too significant, the difference occurs between the value range 0 ~ 1, to determine the level of error, use the Mean Square Error (MSE) with an error level of = 0.5 and Mean Absolute Error (MAE) with an error level of = 0.6. The contribution of this research is an algorithm that can predict the density value (baume) based on the resistance value obtained from the YL 69 sensor.

Regulation of metallothionein genes in the American oyster (Crassostrea virginica): Ontogeny and differential expression in response to different stressors

Gene ◽  
2006 ◽  
Vol 379 ◽  
pp. 156-165 ◽  
Author(s):  
Matthew J. Jenny ◽  
Gregory W. Warr ◽  
Amy H. Ringwood ◽  
David A. Baltzegar ◽  
Robert W. Chapman
Keyword(s):  
Differential Expression ◽  
Crassostrea Virginica ◽  
American Oyster
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