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At least 19 recordsLinked to original sources
PubMed1991

[Isolation of Yersinia, campylobacter, Plesiomonas and Aeromonas from environmental water and fresh water fishes].

Yersinia, Campylobacter, Plesiomonas and Aeromonas are known causative agents in waterborne diseases. For about 10 years, outbreak of diarrhea has been observed, especially among children, in the mountain areas of Okayama. Y. pseudotuberculosis recently isolated from non-chlorinated drinking water sources such as mountain streams and wells has been suspected to be the causative bacteria of the disease. Attempts were made to isolate Yersinia and Campylobacter from water samples from rivers in rural areas and Plesiomonas and Aeromonas from samples of well water and fresh water fishes in Okayama prefecture from 1987 to 1990. The isolation rate of Yersinia from river water samples was 7.5% with a higher rate in the mountain areas than in the nonmountain areas. While Y. enterocolitica was isolated throughout the year, Y. pseudotuberculosis was only seen during the winter. Various serogroups including human types of Y. enterocolitica and serogroup 2B, 4A and UT of Y. pseudotuberculosis were detected. Campylobacter was isolated from 0.5% of river water samples. Plesiomonas from 1.5% of fresh water fishes, and Aeromonas was isolated from 6.9% of well water samples and 47.1% of fresh water fishes.

Aeromonas↗
PubMed1986

Mechanism of inactivation of enteric viruses in fresh water.

Fresh water obtained from nine sources was shown to cause inactivation of poliovirus. Further testing with four of these water samples showed that enteric viruses from different genera were consistently inactivated in these freshwater samples. Studies on the cause of inactivation were conducted with echovirus type 12 as the model virus. The results revealed that the virucidal agents in the waters tested could not be separated from microorganisms. Any treatment that removed or inactivated microorganisms caused loss of virucidal activity. Microbial growth in a sterilized creek water seeded with a small amount of stream water resulted in concomitant production of virucidal activity. When individual bacterial isolates obtained from a stream were grown in this sterilized creek water, most (22 of 27) produced a large amount of virucidal activity, although the amount varied from one isolate to the next. Active and inactive isolates were represented by both gram-positive and gram-negative organisms. Examination of echoviruses inactivated in stream water revealed that loss of infectivity first correlated with a slight decrease in the sedimentation coefficient of virus particles. The cause appeared to be cleavage of viral proteins, most notably, VP-4 and, to a lesser extent, VP-1. Viral RNA associated with particles was also cleaved but the rate was slower than loss of infectivity. These results suggest that proteolytic bacterial enzymes inactivate echovirus particles in fresh water by cleavage of viral proteins, thus exposing the viral RNA to nuclease digestion.

Enterovirus B, Human↗
PubMed1992

Effect of vitamin D3 administration on the serum calcium and inorganic phosphate levels of the freshwater catfish, Heteropneustes fossilis, maintained in artificial fresh water, calcium-rich fresh water, and calcium-deficient fresh water.

Freshwater catfish, Heteropneustes fossilis, were injected daily intraperitoneally either with vehicle (0.05 ml of 95% ethanol/100 g body wt) or vitamin D3 (50 I.U./100 g body wt) and maintained in artificial fresh water, calcium-rich fresh water, or calcium-deficient fresh water for 10 days. The specimens were sacrificed on Days 1, 3, 5, and 10 after initiation of the experiment. The blood samples were collected on these intervals and serum calcium and inorganic phosphate levels were analyzed. Vitamin D3 induced hypercalcemia and hyperphosphatemia in the freshwater catfish, H. fossilis. These effects of vitamin D3 are not dependent upon the calcium concentration of the different ambient media used in this study.

Animals↗
PubMed1978

Neurohypophysial hormonal control of kidney function in the Furopean eel (Anguilla anguilla L.) adapted to sea-water or fresh water.

Low doses of arginine-vasotocin (AVT), isotocin and oxytocin (1 pg-1 ng/kg body weight) were antidiuretic in eels adapted to fresh water but not in those adapted to sea-water. High doses (more than 10 ng/kg) were always diuretic. No effects on tubular water reabsorption were observed and the glomerular filtration rate (GFR) was proportional to the maximum reabsorptive rate for glucose (Tm(glucose)) in eels adapted to sea-water. Increases in urinary flow appeared therefore to result from glomerular recruitment. Infusion of AVT or isotocin at low rates reduced the GFR and urinary flow of freshwater eels to the levels found in seawater eels. Vasopressin (lysine or arginine) had no direct effect on kidney function in freshwater eels but blocked both the diuretic and antidiuretic actions of the other hormones. When infused into seawater eels it was diuretic. This effect could have been due to blockade of the actions of endogenous AVT and/or isotocin.

Adaptation, Physiological↗
PubMed1989

[Studies on motile-Aeromonas infection: incidence of motile-Aeromonas in river mud, river water and fresh-water fish].

During the period from October 1982 to July 1984, a total of 1,157 specimens that consisted of 132 river and lake water, 514 river and lake muds, and 511 fresh-water fish caught in both Tama River and Sagami River were examined the presence of the organisms. Of them, 132 (100%) river and lake waters, 304 (59.1%) river and lake muds, and 462 (90.4%) intestinal contents of fresh-water fish were found to have harbor a mean concentration of 1.3 x 10(3)/l, 1.6 x 10(6)/g, and 1.1 x 10(6)/g of motile-Aeromonas respectively. However, nonseasonal variation was observed in the incidence of the organisms throughout the period of investigation. When attempts were made to classify the isolates by the method described Popoff et al., 17 (14.2%) of 120 water-isolates were typed as A. hydrophila, 33 (27.5%) as A. sobria and 35 (29.2%) as A. caviae respectively. And the rest of the 35 (29.2%) remained untypable. As for the 176 mud-isolates, 38 (21.6%) were typed as A. hydrophila 23 (13.1%) as A. sobria and 41 (23.3%) as A. caviae respectively. And the rest of 74 (42.0%) remained untypable. Some efforts were made on the 1,056 strains obtained from fresh-water fish, and 182 (17.2%) were typed as A. hydrophila, 332 (31.4%) as A. sobria and 206 (19.5%) as A. caviae respectively. And the rest of the 336 (31.8%) remained untypable.

Aeromonas↗
PubMed1992

[Fresh water aquariums and veterinary practice. 1. Principles of fresh water aquariums].

Although aquarium fish belong to the most frequently-kept pets they are very rare as patients in veterinary clinics. Besides the fact that the cost of the single fish is usually low, one reason might be that a sick fish has always to be seen in the context of its aquarium conditions, and that most veterinarians lack knowledge of required parameters. The following summary is intended to give an overview of the factors that are important for an optimal functioning aquarium, and with that for the health and well-being of the animals. Knowledge of these factors will help in the recognition and prevention of diseases resulting from management faults.

Animals↗
PubMed1977

Studies on glycosphingolipids of fresh-water bivalves. IV. Structure of a branched globoside containing mannose from spermatozoa of the fresh-water bivalve, Hyriopsis schlegelii.

1. A second novel globoside, provisionally named Lipid II in the previous study, was obtained from spermatozoa of the fresh-water bivalve, Hyriopsis schlegelii. The structure of this globoside was established by the results of partial acid hydrolysis, methylation studies, and oxidation with chromium trioxide. 2. The structure was shown to be GlcNAcbeta(1 leads to 2)Manbeta(1 leads to 3)[Xylbeta(1 leads to 2)]Manbeta(1 leads to 4)Glcbeta-(1 leads to 1)-ceramide. It is structurally related to the previously described globoside (Lipid I), except that a branched xylose is linked to the heterooligo saccharide chain of the latter lipid. 3. The predominant fatty acids were palmitic and stearic acids, and octadeca-4-sphingenine was the principal base, amounting to 70% of the total. The fatty acid and long-chain base compositions show nearly the same distribution in both of these globosides.

Animals↗
PubMed1977

Studies on glycosphingolipids of fresh-water bivalves. III. Isolation and characterization of a novel globoside containing mannose from spermatozoa of the fresh-water bivalve, Hyriopsis schlegelii.

Three globosides were isolated from spermatozoa of the fresh-water bivalve, Hyriopsis schlegelii by mild alkaline hydrolysis, acetone precipitation, Unisil column chromatography and preparative thin-layer chromatography. These globosides are unique in their sugar chains, since they contain mannose instead of galactose found so far in all globosides of mammals and other animals examined. The main globoside in the spermatozoa was characterized as Glc-NAcbeta(1 leads to 2)Manbeta(1 leads to 3)Manbeta(1 leads to 4)Glcbeta(1 leads to 1)-ceramide by partial acid hydrolysis, analysis of its anomeric configuration with chromium trioxide, methylation analysis and enzymatic hydrolysis. The globoside contained normal saturated fatty acids ranging in length from C16 to C21, palmitic and stearic acids being predominant. Its main long-chain was octadeca-4-sphingenine.

Animals↗
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↗
PubMed1992

Maudsley reactive and nonreactive rats in the forced swim test: comparison in fresh water and soiled water.

Maudsley reactive (MR) and nonreactive (MNRA) and Sprague-Dawley (SD) male rats were tested for their immobility response in the forced swim test when the water was fresh or soiled by a rat of the same or other strain. For all strains, rats tested in soiled water were less immobile than rats in fresh water. The three strains did not differ as producers of soiling substance, but did differ in their response to it. The MR strain was least responsive, whereas the MNRA and SD did not differ from one another. These results support a previous study suggesting that MR rats are more immobile than MNRA rats in the forced swim test. The interpretation of these findings regarding the use of the Maudsley rat strains as an animal model for studying anxiety and/or depression is discussed.

Animals↗
PubMed1979

Ultrastructure of chloride cells in young adults of the anadromous sea lamprey, Petromyzon marinus L., in fresh water and during adaptation to sea water.

The chloride cells in the interlamellar areas of the gills of young adult, anadromous sea lampreys, Petromyzon marinus L., captured in fresh water undergo structural modification during the adaptation of these animals to sea water. In fresh water the chloride cells are partially overlapped by mucus-secreting superficial cells and contain an extensive reticulum of cytoplasmic tubules, which are confluent with both lateral and basal plasma membranes, numerous mitochondria, a Golgi complex of moderate size, and numerous apical vesicles. Adaptation to sea water results in a retraction of the superficial cells, exposing the entire apical surface of the chloride cells, and a proliferation of both cytoplasmic tubules and mitochondria. Extensive enlargement of the Golgi complex in the chloride cells of these animals suggests the involvement of this organelle in the proliferation of cytoplasmic tubules. The extracellular tracer, ruthenium red, enters the tubules from the lateral or basal intercellular spaces in both freshwater- and seawater-adapted animals but never enters either tubules or vesicles from the apical surfaces, indicating that these are not confluent. The presence of dividing basal cells and newly-forming chloride cells, combined with evidence of degeneration of chloride cells, suggests that there is a turnover of this cell type. Both superficial and basal cells are phagocytic and involved in heterophagy of degenerating chloride cells. This phenomenon occurs in both fresh water and sea water indicating that the chloride cells may be functional in both environments.

Adaptation, Physiological↗
PubMed1991

Plasma prolactin and cortisol concentrations of stressed coho salmon, Oncorhynchus kisutch, in fresh water or salt water.

Juvenile coho salmon, Oncorhynchus kisutch, adapted to fresh water or seawater were either acutely handled or continuously stressed by severe confinement. Chronic stress, independent of external salinity, caused a gradual increase in the concentration of circulating prolactin that persisted for 1 to 5 days but lagged behind the cortisol response which peaked much more rapidly and remained elevated. Acutely stressed fish showed a rapid, more transient increase in plasma cortisol titer with no apparent effect on prolactin. Confinement appeared to be more stressful to fish in salt water than to those in fresh water, as judged by their sodium regulatory ability, hormone profiles, and mortality. Stress always elevated plasma prolactin concentrations, regardless of medium or developmental stage.

Animals↗
PubMed1991

[Increase in skin blood circulation and transcutaneous oxygen partial pressure of the top of the foot in lower leg immersion in water containing carbon dioxide in patients with arterial occlusive disease. Results of a controlled study compared with fresh water].

Semi-quantitative Doppler laser flowmetry and measurement of transcutaneous oxygen partial pressure (TCPO2 in mmHg) are reliable, non-invasive methods of continuous measurement suitable for underwater use. We measured the effect of aqueous CO2 (succinate + sodium bicarbonate = Kao Bub; 1400 mg CO2 per kg water) compared with fresh water (both at 34 degrees C, depth of leg immersion 35 cm, immersion time 20 min) on circulation and TCPO2 in the feet of 15 patients with bilateral stage-II occlusion of the Aa. fem. superf. intraindividually in a randomised, crossover trial. Measurements were made at the same time of day on two consecutive days. No change in either cutaneous microcirculation or TCPO2 was observed during immersion in fresh water. During immersion in a CO2 bath both culaneous blood flow (as expressed by Doppler laser flux) and the amplitude of the Doppler laser vasomotion flux increased more than threefold (p less than 0.001, Wilcoxon), while sitting TCPO2 increased by over 10% (from 63 to 71 mmHg; p less than 0.001). The observed changes in oxygen dissociation and cutaneous microcirculation may help to provide an explanation for the well-known therapeutic effect of CO2 baths in all stages of occlusive arterial disease.

Adult↗
PubMed1975

Uptake and excretion of organophosphorus and carbamate insecticides by fresh water fish, motsugo, Pseudorasbora parva.

Fresh water fish, Motsugo was reared in aquarium water tank containing about 1 ppm of 3 organophosphorus and 3 carbamate insecticides for about 30 days. The persistence of these insecticides in water and uptake and excretion of insecticides by fish were examined. Among organophosphorus insecticides, malathion is the most unstable in water, and degraded more than 99% for 7 days. Fenitrothion is moderately stable, and degraded 97% for 29 days. Diazinon is the most stable, and degraded 72% for 30 days. Among carbamates, carbaryl is the most unstable in water, and degraded more than 95% for 6 days. BPMC is moderately stable, and degraded 80% for 32 days. XMC is the most stable, and degraded 45% for 34 days. As for the uptake of the pesticides by fish, organophosphorus insecticides were generally higher than carbamate insecticides. The concentration of diazinon in fish reached to 211 ppm of the maximum level after 3 days, and that of fenitrothion reached to 162 ppm of the maximum level after 4 days. Afterwards, the concentration of both the insecticides decreased gradually due to the metabolism and excretion of the insecticides in fish. Uptake of malathion was very low and metabolized rapidly, and its concentration became to less than 0.01 ppm after 7 days. Among carbamate insecticides, the concentration of carbaryl in fish after one day reached to 7.5 ppm which was the maximum level of uptake. On the other hand, the concentration of BPMC in fish after 4 days became to 4.8 ppm, which was the maximum level, and decreased gradually. The concentration of XMC in fish was only 1.4 ppm after one day, but the metabolism rate of XMC in fish was fairly slow. Therefore, 0.55 ppm of XMC in fish remained even after 34 days. Moreover, in the test tank of diazinon, fenitrothion and BPMC, the appearance of deformed fish with spinal curvature of back bone came out at the rate of 10 to 30%.

Animals↗
PubMedDate not supplied

[Ultrastructure of prolactin cells of three Mugilidae during adaptation to fresh-water (author's transl)].

The behaviour of three species of Mugilidae (Mugil ramada, Crenimugil labrosus and Mugil auratus) during adaptation to fresh water is very different. Those differences may be explain by variants of their prolactin cells activity. The adaptation of Mugil ramada and Crenimugil labrosus to fresh water is easy and last over a long time; the prolactin cells, with a slow activity in sea water, become during adaptation more active. In Mugil auratus in sea water, prolactin cells present already a sign of strong activity. After transfert in fresh water, they appear to be unable to increase their activity. The adaptation of this species is difficult and short-lasting.

Adaptation, Physiological↗