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1.
SUMMARY. Histological and electron microscopical study of the gills of fish poisoned by the anionic detergent sodium lauryl sulphate indicates that the nature of the toxic action changes at a concentration of about 120 mg I−1. Toxicity tests were conducted to determine whether this change could be detected in the test data, using brown trout ( Salmo trutta ) and rainbow trout ( S. gairdneri ).
Toxicity curves showed no indication of the change in toxic action, but at concentrations of 120 and 130 mg I−1 of sodium lauryl sulphate 'split' probit lines occurred, and the lines for 150 mg I−1 consistently differed in slope from other lines.  相似文献   

2.
The pathological effects often lethal concentrations of the anionic detergent, sodium lauryl sulphate, on the gills of Salmo trutta L. have been studied by light and electron microscopy. At concentrations to 120 mg/1 (medium survival times >1 h), epithelial cell death is associated with lysosome formation. Acute inflammation of the gill tissue, extensive detachment of the epithelium and, except at the lowest concentrations, collapse of the pillar cell system occur. At concentrations above 120 mg/1 (medium survival times <1 h) very rapid lysis of cells results in the complete disruption of cellular and tissue structure. Changes in the gross structure of the gills are explainable in terms of the rate and nature of toxic action at the cellular level. Review of the biomedical literature suggests the observed effects of sodium lauryl sulphate on gill cells correspond to the two mechanisms by which detergents cause death in isolated cells. These are autolysis, i.e. lysis by the action of the cell's own enzymes, induced by an initial lesion in the cell membrane whose precise nature is not known; and rapid lysis by the direct action of the detergent on the cell constituents.  相似文献   

3.
1. Strontium absorption was studied in vivo with loops of ileum in rachitic chicks and found to be increased by vitamin D(3), bile salts and sodium lauryl sulphate. 2. Bile salts and sodium lauryl sulphate rendered strontium soluble in butanol-benzene (1:1, v/v). 3. Bile was not concerned in the absorption of iron in rats from its water-soluble form, ferrous sulphate. 4. Ligation of the bile ducts in rats caused a decrease in the absorption of iron presented as its sparingly soluble phosphate. 5. The effect of bile on cation absorption is discussed.  相似文献   

4.
A high-performance liquid chromatographic separation of proguanil, cycloguanil and 4-chlorophenylbiguanide is reported using a hydrophobic stationary phase and lauryl sulphate as pairing ion. It is suggested, on the basis of the behaviour of phenylbenzoate as an undissociated solute and the variation of retention with lauryl sulphate and sodium ion concentrations that the mechanism of separation is one of ion exchange. The biguanides can be detected in serum at concentrations in the region of 60 ng ml-1 and preliminary results are presented to show the variation of proguanil in serum over a 24-h period following ingestion of 200 mg orgally.  相似文献   

5.
The aim of the present study was to evaluate the induced genotoxicity (DNA damage) due to organophosphate pesticide profenofos (PFF) in gill cells of freshwater fish Channa punctatus using single cell gel electrophoresis (SCGE)/Comet assay. The 96h LC(50) value of PFF (50% EC) was estimated for the fish species in a semistatic system and then three sub-lethal of LC(50) concentrations viz the sub-lethal 1, sub-lethal 2 and sub-lethal 3 concentrations were determined as 0.58ppb, 1.16ppb and 1.74ppb, respectively. The fish specimens were exposed to these concentrations of the pesticide and the gill tissue samplings were done on 24h, 48h, 72h and 96h post exposure for assessment of DNA damage in terms of percentage of DNA in comet tails. In general, a concentration dependent response was observed in the gill cells with induction of maximum DNA damage at the highest concentration of PFF. The results of the present investigation indicated that PFF could potentially induce genotoxic effect in fish, even in sub-lethal concentrations and SCGE as a sensitive and reliable tool for in vivo assessment of DNA damage caused by the genotoxic agents.  相似文献   

6.
Four detergent actives, sodium lauryl sulphate, DOBS 055, Dobanol 25 sulphate LCU and Dobanol 25 sulphate HCB, were fed to rats in the diet for 90 days at the maximum tolerated dose, 1.13 percent active ingredient in each case. Sodium lauryl sulphate and DOBS 055 were also fed at half this concentration. Chromosome preparations were made from the bone marrow and scored for the presence of rearrangements, chromatid gaps and breaks and isochromatid gaps and breaks. The four detergent actives were found to have no effect on the chromosomes of rat bone marrow cells.  相似文献   

7.
The objective of this study was to investigate early biological response in olive flounder exposed to sub-lethal concentrations of waterborne phenanthrene (0.5, 1 or 2 microM). The fish were exposed for 4 weeks and we analyzed their enzymatic defense system, antioxidant and phase II enzyme activities, to evaluate the chronic exposure toxicity of phenanthrene. Waterborne phenanthrene affected antioxidant enzymes and glutathione-mediated detoxification as enzyme defense system. Hepatic, gill and kidney glutathione reductase as well as glutathione S-transferase, and catalase activities were markedly elevated after two or four weeks of exposure. These enzymes activities of olive flounder, Paralichthys olivaceus seem to be a convenient tool for monitoring pollution in coastal areas against PAHs pollution including phenanthrene.  相似文献   

8.
Sublethally heated spores of Bacillus subtilis NCTC 8236 were susceptible to posttreatment concentrations in agar of polymyxin B sulphate, sodium hydroxide, cetylpyridinium chloride and sodium lauryl sulphate that did not prevent colony formation to untreated spores. The non-ionic surfactants polysorbates 20 and 80 were not inhibitory when used at high concentrations against both heated and unheated spores. The method has been developed for detecting sublethal injury in biocide-exposed spores, since iodine-treated spores became highly susceptible to polymyxin contained in recovery agar.  相似文献   

9.
AIMS: To determine the role played by previous growth in the presence of osmolytes on the subsequent survival and sub-lethal injury of L. monocytogenes during long-term chilled storage in a model buffer system. METHODS AND RESULTS: Four Listeria monocytogenes strains were grown separately to stationary phase in Listeria minimal medium (DM) alone or in DM with 4% NaCl alone, or both these media supplemented with 1 mM L-carnitine and/or 1 mM glycine betaine. Cells were resuspended in phosphate buffered saline (pH 5.5) and stored for four weeks at 4 degrees C. Initially, and at weekly intervals, samples were plated on both Tryptic Soy Agar and Tryptic Soy Agar with 4% NaCl to determine total numbers and degree of sub-lethal injury in the populations. The numbers of cells within all strains after growth to stationary phase, except one which increased ( approximately 2 log cfu ml-1, P < 0.05) in the presence of NaCl, were not influenced significantly by previous growth conditions (P > 0.05). During subsequent chilled storage, however, numbers of all strains grown in the presence of NaCl remained constant while those grown in its absence decreased. The rate and magnitude of the decrease in cell numbers was strain dependent. The initial percentage of sub-lethal injury increased significantly in all strains when grown previously in the presence of L-carnitine (P < 0.05). During subsequent chilled storage sub-lethal injury increased for all strains in a manner that was strain dependent, but not related to the previous growth conditions. CONCLUSION: Previous growth in the presence of osmolytes of NaCl, but not osmolytes alone, increases the subsequent survival, but not percentage sub-lethal injury, of L. monocytogenes during subsequent chilled storage in buffer. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that risks associated with L. monocytogenes in chilled food may be influenced by the individual life histories of the cells.  相似文献   

10.
Polychlorinated biphenyls (PCBs) are persistent xenobiotics within aquatic environments, which elicit diverse toxic effects such as induction of oxidative stress. Despite numerous earlier studies, no detailed information exists on the toxic response by different sexes in fish. The aim of this study was to determine sex-linked differences in oxidative stress response and antioxidant defenses in Girardinichthys viviparus, an endangered fish endemic to Mexico, when exposed to sub-lethal concentrations of waterborne PCBs. The biological markers evaluated were lipid peroxidation (LPOX), superoxide dismutase (SOD) and catalase (CAT) activity. Adult eight-month-old specimens born in the laboratory were exposed to (1/2) of the LC0 (0.92 mg PCBs/L) in semi-hard synthetic water and sacrificed on days 1, 2, 4, 8 and 16 for biomarker assays. Sex-linked differences were observed in the control fish with respect to all three factors assayed. PCBs elicited significant (p<0.01) time- and sex-dependent LPOX levels which were higher in the case of males. In PCB-treated G. viviparus, SOD activity was depressed in both sexes and appears to return to pre-exposure levels after 16 days in males only. In contrast, CAT was significantly induced (p<0.01) in both sexes. This enzyme may be responsible for balancing oxidative stress and antioxidant defenses under experimental conditions. PCBs at sub-lethal concentrations are hazardous to both sexes of G. viviparus since these compounds are able to induce liver LPOX and changes in the antioxidant defense activities. The relationship between these biomarkers and cytochrome P450 and CYP1A induction is also discussed.  相似文献   

11.
Two experiments were carried out to investigate the influence of confinement stress on plasma cortisol levels and on the sensitivity of the interrenal cells to adrenocorticotropic hormone (ACTH) stimulation in sea bass Dicentrarchus labrax. Confining sea bass at 70 kg m(-3) for 24 h resulted in elevated plasma cortisol levels at all times (0.1, 1, 4 and 24 h) and corresponded to a reduced cortisol content in head-kidney homogenates after 0.1 and 1 h of confinement. An increased activity of the interrenal cells was also indicated by the enlarged nuclear diameters measured after 1 and 4 h of confinement. In vitro superfusion experiments showed that 4 h of confinement resulted in an increased basal unstimulated release of cortisol from head-kidney tissues compared with that in unstressed control fish. Although the stimulation factor (cortisol release as percent increase above basal) of the stressed fish was significantly lower than in controls, no difference in the maximal stimulated release (in absolute amounts) was evident between stressed and control fish. Care must be taken when interpreting superfusion data, as to whether the stressor actually leads to a reduction in interrenal sensitivity, or is due to an alteration in the basal release of cortisol.  相似文献   

12.
Present methods of extracting prostagalndins (PGs) give poor recoveries from synovial fluid, probably because the PGs bind to protein and are lost in the precipitation stage of extraction. Addition of the nonpolar detergent sodium lauryl sulphate prior to extraction improves recovery of PGs. It is suggested that sodium lauryl sulphate competes with PGs for the binding sites.  相似文献   

13.
10. Trout Salmo irideus are adapted to sea water (S W) within four weeks by submitting them to a stepwise increase in external salinity (successively: 1/3 SW, 1/2 SW, 3/4 SW, full SW). 20. In completely adapted individuals mean plasma electrolyte concentrations vary only slightly (by a few %) from one medium to another. Thus, the trout may be regarded as a euryhaline, eventually homeosmotic species. 30. With increasing outside salinity there is a progressive diminution in the overall gill permeability to ions which is suggested by saturation curves obtained for sodium fluxes (maximum at about 500 muEq/h. 100 g at 15 degrees C, for unshocked fish). 40. Disturbance of the animals provokes a striking elevation and desequilibrium in these exchanges and this in turn induces an abnormal rise in plasma concentrations and a subsequent failure to adapt to hypertonic media. 50. In vitro absorption of water and sodium by intestinal everted-sacs increases only after transfer to full sea water. Mucosal entry of ions into intestinal epithelial cells measured by the technique of Schultz et al. (1967), is diminished in sea water-adapted animal (by 42% in the case of sodium). 60. These results demonstrate that Salmo irideus possesses efficient osmoregulatory mechanisms which operate with minimal energy expenditure in hypertonic media.  相似文献   

14.
Vitamin D3 and calcium absorption in the chick   总被引:2,自引:2,他引:0       下载免费PDF全文
1. An attempt has been made to locate the site of action of vitamin D(3) as it affects the translocation of calcium across the intestine. 2. Calcium appears to be pumped out of cells by a process dependent on energy from metabolism. 3. The effects of cold, inhibitors and vitamin D(3) on the translocation of calcium by everted sacs of intestine were studied and compared with results obtained in vivo. 4. A model was proposed to explain the results which suggests that vitamin D(3) inhibits a metabolically operated pump that returns calcium from the mucosal cell to the lumen. 5. Some observations on the effect of sodium lauryl sulphate on the translocation of calcium in vivo and in vitro are reported.  相似文献   

15.
Summary The ultrastructure of the interrenal (adrenocortical) cells of trout (Salmo fario L.) was studied after dexamethasone treatment. A procedure for identifying and isolating interrenal tissue fragments from the surrounding head kidney tissue prior to their preparation for electron microscopy is described. The peripheral plasma cortisol concentrations were measured in order to evaluate the steroidogenic activity of this tissue.The interrenal cells of control animals contain numerous mitochondria with tubular cristae, and a well developed and highly organized smooth endoplasmic reticulum (SER). The scarcity, or absence, of lipid droplets contrasts markedly with the abundance of SER.Treatment with dexamethasone results in a decrease steroidogenic activity of the interrenal cells, as indicated by the fall in plasma cortisol concentrations. The interrenal cells are small, but still contain numerous mitochondria. The SER is poorly developed, but masses of densely intermeshed smooth cisternae subsist. Lipid droplets do not accumulate in these cells; this peculiarity is discussed in connection with the virtual absence of liposomes in teleost interrenal cells.  相似文献   

16.
Lettuce big-vein disease is transmitted from diseased to healthy plants by zoospores of the lettuce root-infecting fungus Olpidium brassicae. A laboratory technique based on microscopical examination of Olpidium Zoospores is described for assaying the toxicity of chemicals to zoospores. Chemcials found to kill zoospores in <1 h included copper (4 μ/ml), zinc (10μ/ml), diluted preparations of carbendazim (methyl-2-yl-benzimidazole carbamate) as Bavistinand a formulation of Bavisitin containing no carbendazim. Bavistn controlled the disease when introduced at a concentration of 0.6 g/litre into a lettuce crop grown in a re-circulated film of nutrient. Various surfactants inlcuding Agral, Cetrimide, Deciquam, Ethylan CPX, Hyamine 1622, Manoxol/OT and sodium lauryl sulphate were toxic to zoospores at concentrations of 1–10 μ/ml.  相似文献   

17.
The mammalian ACTH (20 I.U.) injected in Heteropneustes fossilis (Bloch) caused hyperplasia of the adrenocortical tissue. The interrenal as well as chrome cells became vacuolated. The interrenal nuclear size increased by 15% as an average than the control fishes. The glycogen granules were found to be absent from the interrenal cells. The effect of bilateral gonadectomy in both sexes has been marked in the gradual decrease of the interrenal nuclear diameter which 12 weeks after the operation, recorded nearly 25% reduction in size. The glycogen content was reduced considerably. Removal of gonads during maturation period bringing inhibition of hyperplasia of the gland at the time of spawning possibly indicates action of gonadal steroids on the physiological alterations of the interrenal cells.  相似文献   

18.
We have investigated the chemical composition of the rectal contents, faeces and urine of the blood-sucking bug Triatoma infestans. This is the environment in which the important disease-causing organism, Trypanosoma cruzi, lives. Directly after feeding of Triatoma infestans, the pH of the excreta switched from an acidic to an alkaline pH and, 1 day later, back to a slightly acidic pH. The osmolality varied in the initial excreta and in the rectal contents on the day following the meal between 300 and 460 mosmol/kg H(2)O, but after an additional day it increased to 350-970 mosmol/kg H(2)O. Determinations by ion capillary electrophoresis showed that sulphate and phosphate dominated the rectal contents in unfed bugs. After feeding, the first four drops of fluid excreta were mainly a sodium chloride solution (>150 mM for each). One to 10 days after feeding strong individual variations in the concentrations of individual ions were evident, especially for potassium and sodium. Mean concentrations of chloride remained at about 70 mM; sulphate and phosphate showed an increase within the first 1 or 2 days and then reached a level of about 160 and 210 mM, respectively. The rectal contents of long-term starved bugs contained high concentrations of phosphate and potassium; sulphate and sodium were slightly lower.  相似文献   

19.
Living protoplasts were isolated from the interplacental regions of Lycopersicum pimpinellifolium berries by the removal of the walls from cells in tissue slices treated for 1–2 h with 10 % pectinase in 0.5 M sucrose solution. Protoplasts thus isolated, then washed and transferred to microculture chambers for observation were invariably spherical. Each protoplast contains a nucleus, a number of chloroplasts of variable shape and a vacuole with smaller vacuoles contained therein. Phase contrast optics reveal cytoplasmic granules, the size of mitochondria, which serve to indicate such dynamic processes as cyclosis. Treatment with ox bile salt and sodium lauryl sulphate cause rapid disruption of the protoplasts producing subprotoplasts and isolated tonoplasts and serves to confirm the absence of rigid cell walls.  相似文献   

20.
The impact of hypophysectomy on the state of the interrenal gland and ultrastructure of chloride cells of gills is investigated in 18-month old juveniles of starred sturgeon Acipenser stellatus in the process of its adaptation to artificial sea water (14.6‰). Hypophysectomized juveniles, similarly to intact juveniles, are able to support a relative stability of osmolarity of blood serum in the course of adaptation to sea water by transition from hyperosmotic to hypoosmotic type of osmoregulation. Changes in the investigated parameters of cells of the interrenal gland (volume of nuclei, areas of cells and of lipophilic vacuoles) occurring in the hypophysectomized and in intact specimens in the process of adaptation to sea water are generally similar, but have different dynamics. In contrast to many teleostean species, in acipenserids the hypophyectomy does not cause atrophy of the interrenal gland. The latter is incorporated in the process of regulation in the course of adaptation of fish to sea water. Hypophyecotmy results in partial destruction of organoids in some chloride cells of gills. However, when the fish are transferred to sea water, the structural changes occur in chloride cells characteristic of their transition to the excretory state. This may happen only at activation of the transport enzyme Na+/K+-ATPase of these cells by cortisol produced by the interrenal gland. In the absence of hypophysis, the functional connection of organs of the axis hypothalamus (ACTH-immunopositive cells of tuberal nucleus) → the interrenal gland → chloride cells is realized in the fish.  相似文献   

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