Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FISHES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 829 records · Page 46Linked to original sources

Swimming behavior of fish during short periods of weightlessness.

BACKGROUND: Birds and fish show tumbling and spinning movements when subjected to short periods of weightlessness during parabolic flight. The reason for this behavior is not clear. HYPOTHESIS: The semicircular canal system is a rotation-detecting device; however, it seems that linear accelerations have an influence, too. Microgravity induces rotatory sensations which leads to a compensatory behavior (e.g., rotatory movements). METHODS: The swimming behavior of goldfish was studied with the fish in four different conditions: normal fish (group I); fish with one eye recently removed (group II); fish with both eyes recently removed (group III); and fish with both eyes removed 10 months previously (group IV). Further, a group of naturally blind (e.g., not surgically treated) cavefish (group V) were involved in the study also. All procedures conformed to the guiding principles as required in the Dutch Law on Care and Use of Animals. RESULTS: Three main different patterns of abnormal swimming behavior could be observed: tumbling (pitch), corkscrew movements (pitch and roll), and spinning movements (roll). NF did not shown any special swimming pattern. One-eyed fish (group II): mostly corkscrew movements (62%). Blind fish (group III): a mixture of the three movements (17, 22 and 25%). Blind fish (group IV): mostly spinning movements (20%). Cavefish (group V): tumbling (21%), corkscrew movements (12%) and spinning movements (58%). CONCLUSION: Vision is the dominant cue, explaining the behavior of normal goldfish. When vision is absent, the fish relies on vestibular information with respect to orientation. The swimming behavior is presumably caused by an attempt to compensate rotatory illusions. As all movements were shown in the planes of the vertical canals, we conclude that these canals play a dominant role when fish are deprived from proper otolith information.

Animals↗

Postprandial triacylglycerolaemia: the effect of low-fat dietary treatment with and without fish oil supplementation.

OBJECTIVE: This study investigated whether a low-dose of fish oil had the ability to prevent the adverse effects associated with low-fat dietary treatment, namely elevated plasma triacylglycerol (TAG) and reduced high density lipoprotein (HDL) cholesterol concentrations. DESIGN: Thirty-two healthy volunteers participated in the trial, which consisted of four study groups (n = 8): low-fat diet with fish oil supplementation, low-fat diet without fish oil supplementation, full-fat diet with fish oil supplementation and full-fat diet without fish oil supplementation. Low-fat dietary treatment reduced dietary energy derived from fat by at least 10% and the low-dose of fish oil provided 1 g n-3 polyunsaturated fatty acids (PUFA) daily. The postprandial response to a fat-rich test meal (0.5 g/kg pre-trial body weight) was investigated before and after 16 weeks dietary intervention. RESULTS: Fasting plasma TAG concentrations were significantly (P < or = 0.05) reduced by fish oil supplementation and significantly (P < or = 0.05) increased by the low-fat diet alone but not significantly affected following the low-fat diet with fish oil supplementation. The postprandial TAG response was significantly (P < or = 0.05) increased following the low-fat diet with fish oil supplementation. CONCLUSION: This study demonstrated that some of the deleterious effects of a low-fat diet, reduced concentrations of the cardioprotective HDL2 cholesterol fraction and increased fasting plasma TAG concentrations were prevented when a low dose of fish oil was provided with a low-fat diet. However postprandial triacylglycerolaemia is adversely affected when the low-fat diet was supplemented with fish oil.

Adult↗

Fish induced anaphylactic reaction: report of one case.

In the past 2 years, a 4 year-old boy has had an anaphylactic reaction whenever he contacted food prepared with fish. The symptoms included intense itching in the throat and eyes, which progressed to generalized urticaria and facial angioedema. This was accompanied by cough, wheezing and dyspnea. Many fish preparations caused these episodes including several different kinds of fish (cod, tuna, salmon, trout, eel...), fish soup, chopsticks contaminated with fish preparations and canned fish. Elevated levels of total serum IgE (224 IU/ml) and specific IgE for cod (93.1 IU/ml), tuna (> 100 IU/ml), salmon (> 100 IU/ml), trout (64.4 IU/ml), mackerel (41.2 IU/ml) and eel (28.1 IU/ml) were found by the Pharmacia CAP system RAST FEIA in our allergy clinic. A skin prick test for mixed fish extracts (contain flounder, cod and halibut) was positive. A fish challenge test for cod, tuna, salmon, trout and eel all showed anaphylactic reactions. His allergic symptoms stabilized gradually after strictly avoiding ingestion of fish and using drug treatment. He also had a similar anaphylactic reaction to frogs. The best treatment for fish allergy is avoidance. Avoidance of fish may need to include both ingestion and inhalation of cooking vapors.

Anaphylaxis↗

Levels of chlordane compounds in fish muscle, -meal, -oil and -feed.

Cis-, trans-, oxychlordane and trans-nonachlor were determined in the edible part of more than 140 fish samples of 15 different species and in fish meal, -oil and fish feed. The investigated fish included most of the important fish species consumed in Germany. Highest concentrations were found in muscle of marine fish with high or moderate fat content, but also in eel and farmed salmon. Marine fish with low fat content contained only traces of chlordane in the muscle tissue. A relationship between fishing ground and levels of chlordane could not be established. Contamination level of herring was related to the age (length) of the fish. Data are also given for contamination levels of fish meal, -oil and -feed.

Animal Feed↗

Fish consumption and risk of sudden cardiac death.

CONTEXT: Dietary fish intake has been associated with a reduced risk of fatal cardiac end points, but not with nonfatal end points. Dietary fish intake may have a selective benefit on fatal arrhythmias and therefore sudden cardiac death. OBJECTIVE: To investigate prospectively the association between fish consumption and the risk of sudden cardiac death. DESIGN: Prospective cohort study. SETTING: The US Physicians' Health Study. PATIENTS: A total of 20 551 US male physicians 40 to 84 years of age and free of myocardial infarction, cerebrovascular disease, and cancer at baseline who completed an abbreviated, semiquantitative food frequency questionnaire on fish consumption and were then followed up to 11 years. MAIN OUTCOME MEASURE: Incidence of sudden cardiac death (death within 1 hour of symptom onset) as ascertained by hospital records and reports of next of kin. RESULTS: There were 133 sudden deaths over the course of the study. After controlling for age, randomized aspirin and beta carotene assignment, and coronary risk factors, dietary fish intake was associated with a reduced risk of sudden death, with an apparent threshold effect at a consumption level of 1 fish meal per week (P for trend=.03). For men who consumed fish at least once per week, the multivariate relative risk of sudden death was 0.48 (95% confidence interval, 0.24-0.96; P=.04) compared with men who consumed fish less than monthly. Estimated dietary n-3 fatty acid intake from seafood also was associated with a reduced risk of sudden death but without a significant trend across increasing categories of intake. Neither dietary fish consumption nor n-3 fatty acid intake was associated with a reduced risk of total myocardial infarction, nonsudden cardiac death, or total cardiovascular mortality. However, fish consumption was associated with a significantly reduced risk of total mortality. CONCLUSION: These prospective data suggest that consumption of fish at least once per week may reduce the risk of sudden cardiac death in men.

Adult↗

Rapid prenatal diagnosis of trisomy 21 in 5049 consecutive uncultured amniotic fluid samples by fluorescence in situ hybridisation (FISH).

OBJECTIVES: This was a retrospective study on the results of interphase fluorescence in situ hybridization (FISH), performed routinely for chromosome 21 and on ultrasonographic indications for chromosomes 13, 18, X and Y in a series of 5049 amniotic fluid samples. METHODS: Interphase FISH for chromosome 21 was performed in 5049 consecutive amniotic fluid samples for the rapid prenatal diagnosis of Down syndrome. Aneuploidy for four other chromosomes (13, 18, X and Y) was tested following ultrasonographic indications. Karyotypes from standard cytogenetic analysis were compared to the FISH results. RESULTS: Using conventional cytogenetics 3.6% (183/5049) chromosomal anomalies were detected. After exclusion of familial chromosome rearrangements, i.e. balanced autosomal reciprocal or Robertsonian translocations (30/5049) and inversions (19/5049), 2.65% chromosomal anomalies (134/5049) were diagnosed. Of this group 0.18% (9/5049) were chromosomal rearrangements not detectable by FISH and 2.47% (125/5049) were numerical chromosomal anomalies detectable by interphase FISH for chromosomes 13, 18, 21, X and Y. With routine interphase FISH for chromosome 21 and FISH on echographic indication for the other four chromosomes we detected 107/125 of these numerical chromosomal anomalies, i.e. 85.6%. All 70 cases of trisomy 21 were detected by FISH and confirmed with conventional cytogenetics (sensitivity=100%) and there were no false-positive results (specificity=100%). Maternal cell contamination of amniotic fluid samples occurred in 1.27% (64/5049) of samples; 0.26% (13/5049) of these samples were uninformative by FISH due to maternal cell contamination (12/5049) or absence of nuclei in one sample (1/5049). CONCLUSION: In this group of 5049 samples we found that FISH is a reliable technique for the rapid prenatal diagnosis of trisomy 21. The number of uninformative cases due to maternal cell contamination was low. The strategy to perform FISH for chromosome 21 in all samples and only on ultrasonographic indication for the four other chromosomes (13, 18, X and Y) followed by standard cytogenetics is effective.

Amniocentesis↗

Fluorescence in situ hybridization (FISH) for rapid detection of aneuploidy: experience in 911 prenatal cases.

Fluorescence in situ hybridization (FISH) was performed with probes specific for chromosomes 13, 18, 21, X and Y on 911 of 11123 (8.2%) amniotic fluid samples submitted to the present authors' laboratory for cytogenetic analysis over an 8-year period. Altogether 3516 hybridizations were performed with an interpretable FISH result on all chromosomes requested in 884/911 (97%) of cases. An uninformative FISH result occurred in 44 hybridizations among 27 cases (3%). Of a total of 89 karyotypically proven cases with aneuploidy that might have been detected by FISH, the overall detection rate was 84%. An inconclusive or incomplete FISH result occurred in 9/89 (10%) of these proven aneuploid cases. In the remaining 80 informative proven aneuploid cases, correct detection of aneuploidy was accomplished in 75/80 (94%) of samples. A false-negative result occurred in the remaining 5/80 (6%) of such informative cases. Eighteen cases had karyotypically proven abnormalities that could not have been detected by the targeted FISH. Aside from these 18 cases, FISH allowed correct detection of normal disomy in 785/804 (98%) of such cases. An incomplete FISH result occurred in 18 normal disomic cases. There was a single possible 'false-positive' FISH result for chromosome 21. Interphase FISH analysis of uncultured amniotic fluid cells has been shown to be a useful laboratory tool for rapid fetal aneuploidy screening during pregnancy. As with all clinical laboratory diagnostic tests, incomplete or inconclusive results (or even interpretive errors) occur in a small percentage of cases. Nevertheless, FISH results accompanied by other data and by appropriate counseling provide clinicians and patients with valuable information for clinical decision-making surrounding family planning and pregnancy management.

Amniocentesis↗

Effects of Great Lakes fish consumption on the immune system of Sprague-Dawley rats investigated during a two-generation reproductive study.

The effects of Great Lakes fish on food consumption, body and organ weights, and hematological parameters were investigated in the first- (F1) and second- (F2) generation Sprague-Dawley rats assigned to immunological studies. The parent- (F0) generation rats were fed either a control diet or diets containing 5 or 20% lyophilized chinook salmon from Credit River (Lake Ontario, LO) or Owen Sound (Lake Huron, LH). The F1 and F2 pups were exposed to the fish diet in utero, through the dam's milk to 21 days of age and through the respective diets to 13 weeks of age. The study included an F1-reversibility (F1-R) phase in which rats at 13 weeks of exposure to fish or control diets were switched to the control diet for 3 months. Statistically significant effects included increased growth rates in the F1 male rats fed the LH fish diets compared to those fed the LO fish diets; increased liver weights in the F2-generation male rats fed the LH-20% and LO-20% diets compared to those fed the 5% fish diets; reduced thymus weights in the F1-R female rats fed the LO-20% fish diet compared to those fed the LO-5% or LH-20% fish diets and in the F2 male rats fed the LO diets compared to those fed the LH diets; increased kidney weights in the F2 male rats fed the LH-20% diet compared to those fed the LH-5% or LO-20% diets; reduced but reversible effects on red blood cell (RBC), white blood cell (WBC), neutrophil, lymphocyte, and monocyte numbers in the F1-generation female rats fed the fish diets; reduced red blood cell (RBC), white blood cell (WBC), and lymphocyte numbers in the F2 male rats fed the LO diets compared to those fed the LH diets; and reduced WBC and lymphocyte numbers in the F2 female rats fed the LO-20% diet compared to those fed the LH-20% fish diet. These results suggested that long-term exposure to Great Lakes fish contaminants may have adverse effects on some immune-related parameters. The impact of such changes on the functional aspects of the immune system of rats and consequently on human health needs to be further investigated.

Animal Feed↗

Influence of recruit condition on food competition and predation risk in a coral reef fish.

Settlement rate is considered to be a major determinant of the population structure of coral reef fishes. In this study, the effects of larval physiological condition on survival, predation risk and competitive ability are assessed for a small damselfish, Pomacentrus moluccensis. New settlers were collected and fed for 5 days to produce high and low condition (measured as lipid) treatment fish. In a field experiment, pairs (one high and one low condition fish) were transplanted to corals. Persistence over 2 weeks was much higher (100% vs. 25%) in high condition fish. In mixed groups in the laboratory, high condition fish were both aggressively dominant and consumed more of a limiting prey source than low condition fish. In addition, low condition fish were shown to be at much higher risk of predation. All of the low condition fish but only 33% of high condition fish in mixed groups were consumed by fish predators, and in a separate experiment, 73% of feeding strikes by predators were directed at low condition fish. Quality of new settlers can have an important influence on subsequent juvenile survival. The mechanisms for this effect are likely to include a combination of effects of condition on food competition and predation risk.

Animals↗

Nutrient recycling by two phosphorus-rich grazing catfish: the potential for phosphorus-limitation of fish growth.

In ecosystems where excretion by fish is a major flux of nutrients, the nitrogen (N) to phosphorus (P) ratio released by fish can be important in shaping patterns of algal biomass, community composition, primary production, and nutrient limitation. Demand for N and P as well as energy influences N/P excretion ratios and has broad implications in ecosystems where nutrient recycling by fishes is substantial. Bioenergetics and stoichiometric models predict that natural fish populations are generally energy-limited and therefore N/P recycling by fishes is relatively invariant. Yet, the potential for P limitation of growth has not been examined in herbivorous fishes, which are common in many aquatic habitats. We examined N/P excretion ratios and P demand in two P-rich herbivorous catfishes of the family Loricariidae, Ancistrus triradiatus (hereafter Ancistrus) and Chaetostoma milesi (hereafter Chaetostoma). Both fishes are common grazers in the Andean piedmont region of Venezuela where we conducted this study. Mass balance (MB) models indicate that these fishes have a high P demand. In fact, our Ancistrus' P MB model predicted negative P excretion rates, indicating that Ancistrus did not consume enough P to meet its P demand for growth. Direct measurement of excretion rates showed positive, but very low P excretion rates and high N/P excretion ratios for both taxa. To obtain measured P excretion rates of Ancistrus from the MB model, gross growth efficiency must be reduced by 90%. Our results suggest that growth rates of both of these herbivorous and P-rich fish are likely P-limited. If P limitation of growth is common among herbivorous fish populations, herbivorous fishes recycle likely at high N/P ratios and act to diminish the quality of their food.

Animals↗

Fish consumption and time to pregnancy in Japanese women.

The work described in this paper examined the possible relationship between fish consumption and human fecundity among Japanese women using hair mercury level and time to pregnancy (TTP) as indicators of fish consumption and fecundity. We hypothesized that hair mercury concentrations reflect the level of fish consumption and, consequently, can also be taken to indicate the level of intake of organochlorine compounds (OCs) such as dioxins and polychlorinated biphenyls (PCBs) for which fish are the primary source, and which can disrupt normal human reproductive processes. TTP was obtained by a self-administered questionnaire from women who had been delivered of a baby at either of two hospitals in Sendai, Japan, during the period of January 2002-March 2004. Total mercury concentration in their hair (0-3cm from the scalp) was determined by cold vapor atomic absorption spectrometry. Of the 298 women approached, 193 (65%) reported their TTP. The subjects were classified into two groups according to their TTP: group 1, 0-12 months TTP; and Group 2, >12 months TTP. A step-down procedure backward binominal logistic regression analysis was performed by using age, BMI, parity, frequency of intercourse, life-style parameters (smoking, drinking and dietary habits) and hair mercury level of the female subjects and their partners as independent variables. Two separate analyses were performed by including/excluding information on the partners of the subjects. The analyses did not extract hair mercury concentration as significant indicating that fish consumption did not prolong TTP, which was not consistent with the results of our previous study, i.e., in that study frequent fish eaters showed prolonged TTP. Possible reasons of the negative result are discussed and it is suggested that the hair mercury levels in the present study were not an appropriate indicator of fish consumption of the subjects or of their exposure to OCs. Further study on the relationship between fish consumption (and, ultimately, of OCs intake) and fecundity with more appropriate indicators of fish consumption and/or fish-mediated pollutants intake are warranted to characterize the health risk posed by fish consumption.

Adult↗

Biomarkers of oxidative stress in Wallago attu (Bl. and Sch.) during and after a fish-kill episode at Panipat, India.

The present investigation was carried out by sampling water, sediment and fish during a fish-kill episode at Panipat (Haryana, India), and again sampling at the same site was conducted after a gap of two months. During the second sampling no fish-kill was observed and the water was relatively less turbid and clear. Antioxidant profile and lipid peroxidation (LPO) in fish tissues were studied. Analysis was also carried out on the physico-chemical characteristics of water samples along with heavy metal and pesticide analysis in water and sediment samples during and after the episode. Dissolved oxygen level was substantially low during the fish-kill episode. Heavy metals (copper and chromium) and pesticides like BHC (Benzene hexachloride), DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) were also detected during the episode in water and sediment samples. Various oxidative stress biomarkers in liver, kidney and gill tissues in the Indian freshwater fish Wallago attu (Bl. and Sch.) collected from the site were investigated. The levels of reduced glutathione and non-protein thiol were significantly (P<0.001) higher in the liver of Wallago attu collected from Panipat after the fish-kill episode. Ascorbic acid levels in all the tissues did not change significantly after the episode. The LPO in liver, kidney and gills was significantly low (P<0.01-0.001) in all tissues of fish collected after the fish-kill episode. The protein carbonyl levels were significantly low (P<0.05-0.01) in all the fish organs sampled after the fish-kill episode. The findings suggest that industrial effluent may result in the massive loss of a commercial commodity. The simultaneous measurement of the physicochemical parameters of the water samples showed a good correlation between the biomarkers responses and the environmental chemical stress conditions.

Aldrin↗

Radionuclides (lead-210, polonium-210, thorium-230, and -232) and thorium and uranium in water, sediments, and fish from lakes near the city of Elliot Lake, Ontario, Canada.

Radionuclides (210Pb, 210Po, 230Th, and 232Th) and chemical Th and U were measured in water, sediments, and fish tissues (bone, muscle, and gut contents of laketrout, Salvelinus namaycush, whitefish, Coregonus clupeaformis and Prosopium cylindraceum) from four lakes in a watershed affected by U mining and milling operations at Elliot Lake, Ontario, and from control lakes in an adjacent, non-industrialized, watershed. Radionuclide concentration ratios between tissue levels and sediment and water levels were calculated. Annual radionuclide intakes and resulting doses were estimated for humans consuming fish from the watershed. Bone 210Pb levels were higher (186 mBq g(-1) dry wt in laketrout and 230 mBq g(-1) dry wt in one lake whitefish) than in muscle (< 50 mBq g(-1) dry wt in all cases), and generally higher in fish from study lakes than from controls, but no consistent differences were observed among fish species. Similarly, 210Po levels were higher in bone (208 +/- 33 mBq g(-1), in laketrout) than muscle (maximum 26 +/- 4 mBq g(-1), in laketrout), and in study lake populations compared to controls. Laketrout 210Po bone concentrations were higher than previously reported in Canada. Levels of 230Th, 232Th, and Th were below detection limits (20 mBq g(-1), 0.05 microg g(-1)) in body tissues in all fish species. Bone levels of U (14.6 +/- 3.0 microg g(-1), in lake whitefish) were higher than in muscle (most < 0.05 microg g(-1), except 0.12 +/- 0.04 and 0.08 +/- 0.03 microg g(-1) in lake whitefish) in fish from waters affected by industrial activity. In control lakes, bone and muscle levels were lower and not significantly different from each other. Muscle levels did not vary consistently with location. Concentration of 210Pb and U was seen from water and 'gut' material (taken as a surrogate for diet) to bone in laketrout and whitefish, and of U from water to muscle in whitefish, but in no case from sediments to tissues. Human intakes of 210Pb, 210Po, 230Th, 232Th, and U from consuming one meal of fish (375 g) per week could, in aggregate, represent an annual effective dose < 15% of the public dose limit (5 mSv). Monitoring biota living near the decommissioned Elliot Lake U operations, especially of 210Pb levels in fish muscle, with further assessment of human doses attributable to local fish and other animals in the diet, should continue. Because radionuclide effects on fish health (and on other non-human organisms) are of increasing concern, neoplasms, malformations, and reproductive anomalies in local fish deserve examination.

Journal Article↗

Food-protein-induced enterocolitis syndrome caused by fish.

INTRODUCTION: Food protein-induced enterocolitis syndrome (FPIES) occurs in infants. Typical symptoms include profuse vomiting and/or diarrhea several hours after ingestion of a given food. The disorder is a non-IgE mediated food hypersensitivity. The most frequently involved foods are milk and soy, but some cases of FPIES induced by solid foods have been described. We report 14 patients with FPIES due to fish protein. MATERIAL AND METHODS: History and physical examination, skin prick test (SPT) with fish allergens and Anisakis simplex, prick-by-prick test with implicated fish and determination of specific IgE antibodies against fish were performed. In eight children atopy patch test (APT) were also performed. In nine patients an open oral food challenge with the implicated fish was carried out. RESULTS: There were six boys and eight girls, aged from 9 to 12 months at diagnosis, with between two and six reactions to the offending fish proteins before the diagnosis was established. Four patients had a previous history of atopy. Presenting symptoms included diarrhea in two patients, profuse vomiting in six patients, and recurrent vomiting and subsequent diarrhea in three patients. In addition to these symptoms, associated septic appearance, apathy and lethargy were present in the remaining three patients. Onset of symptoms occurred a few minutes after fish ingestion in two patients and from 60 minutes to 6 hours in the 12 remaining patients. SPT to fish were negative in all patients. Serum food-specific IgE antibodies were negative in all patients except one. APT was positive in three patients. Open oral challenge (OC) was performed in nine infants and was positive in all. The patients were followed-up for between 1 and 7 years after diagnosis, and follow-up OC tests were performed after fish had been eliminated from the patients' diet for 3-4 years. Four patients became clinically tolerant to the causal food. Three patients currently tolerate only one type of fish (swordfish). CONCLUSIONS: We report 14 patients with FPIES caused by fish protein. The symptoms suggest a form of cell-mediated, non-IgE mediated food hypersensitivity. The gold standard for diagnosis is OC, although caution should be exercised in infants with several reactions or a recent diagnosis. After a period of elimination of the causal food from the diet, tolerance can develop.

Animals↗

Effect of dietary fish oil, vitamin E, and probucol on renal injury in the rat.

Dietary fish oil, vitamin E, and probucol have been considered in a variety of human and experimental models of kidney disease. Using subtotal nephrectomized cholesterol-fed rats as a model for progressive kidney disease, we examined the effect of 5% dietary fish oil, or a combination of 5% dietary fish oil with 500 IU vitamin E/kg diet or 1% probucol on renal injury. Three-month-old Sprague Dawley rats were fed a control diet (C group) or a cholesterol supplemented (2%) diet (Ch group) containing either fish oil (FO group) or fish oil plus vitamin E (FO+E group) or fish oil plus probucol (FO+P group). After 4 weeks of dietary treatment, the right kidney was electrocoagulated and the left kidney nephrectomized. After 8 weeks, 24-hour urine was collected before sacrifice. No effect of the dietary treatments was noted on serum creatinine, blood urea nitrogen, or proteinuria, except that proteinuria was highest in FO+P group. Rats receiving the cholesterol diets had higher serum low density lipoprotein (LDL) + very low density lipoprotein (VLDL) cholesterol (P < 0.05). In contrast, rats in the FO+P group had the lowest serum total cholesterol and LDL+VLDL cholesterol among all groups. The FO group had 26% lower kidney alpha-tocopherol concentrations than the C group. However, inclusion of vitamin E in the diet (FO+E group) increased the kidney alpha-tocopherol status to a level comparable to that in the C group, whereas inclusion of probucol in fish oil diet (FO+P group) did not improve the kidney alpha-tocopherol status. Rats fed the cholesterol diet had a 2.5-fold higher glomerular segmental sclerosis (GSS) score and 1.5-fold higher glomerular macrophage (GM) subpopulation than the C group. These effects of the cholesterol diet were ameliorated by a fish oil diet (FO group: GSS by 30%, GM by 24%). The inclusion of vitamin E in the fish oil diet (FO+E group) did not further improve the GSS score or GM subpopulation. However, inclusion of probucol in fish oil diet (FO+P group) lowered the GSS score by 73% and reduced GM subpopulation by 83% compared with the Ch group. These remarkable changes can be attributed to the powerful hypocholesterolemic activity of probucol. Our findings indicate that progression of glomerular sclerosis in the rat remnant kidney model of progressive kidney disease can be significantly modulated with fish oil treatment.

Journal Article↗

Identification and characterization of allergens in two species of tuna fish.

BACKGROUND: In countries where fish consumption is high, allergenic reactions to fish are common among patients diagnosed with food hypersensitivity. For tuna fish, allergenic proteins are not known. In addition, it is not known how the tuna fish extracts should be processed to obtain optimal in vitro diagnostic performance and to preserve labile antigens. OBJECTIVE: The aim of this study was to characterize IgE-binding components of Yellowfin and Albacore tuna fish. METHODS: Various tuna fish extract preparations were fractionated by sodium dodecylsulfate-polyacrylamide gel electrophoresis and transferred to nitrocellulose and analyzed by using tuna positive patients with different Western blot profiles. The functional activity of the extracts was evaluated by basophil histamine release. RESULTS: Immunoblot analysis showed the majority of patients responding to Yellowfin tuna extract. Inhibition studies using immunoblot analysis and histamine release testing showed a specific protein with a molecular weight of approximately 46 kD that is present in Yellowfin tuna, but absent in Albacore. Only defatted, lyophilized tuna fish extracts were able to induce histamine release from sensitized basophils although IgE-binding components were detected in fresh raw, fresh cooked, and canned tuna fish preparations. CONCLUSION: These studies indicate that patient sera may contain different tuna fish species IgE specific antibodies directed against unique species specific allergens present in Yellowfin and Albacore tuna fish. Possibly, extracts should contain specific allergenic components from both Albacore and Yellowfin to cover the epitope heterogeneity observed in sera from patients developing IgE antibodies against tuna fish.

Allergens↗

Maternal diet during oogenesis is the major source of methylmercury in fish embryos.

Development of the early life stages of fishes can be affected adversely by methylmercury (MeHg) transferred from the maternal parent to the developing egg. We examined maternal transfer of MeHg to eggs of fathead minnows Pimephales promelas and evaluated the role of maternal MeHg burden versus that in the maternal dietduring oogenesis on egg concentrations. Juvenile fish were fed one of four diets until sexual maturity (phase 1): A control diet (0.06 microg of Hg g(-1) dry weight) and three that were contaminated with MeHg at 0.88 (low), 4.11 (medium), and 8.46 microg of Hg g(-1) (high). At sexual maturity, female fish were paired with a male, again fed one of the four diets, and allowed to reproduce (phase 2). To assess the significance of female dietary exposure during oogenesis on MeHg in eggs, some fish were fed diets during phase 2 that differed from those during phase 1. Mean concentrations and burdens of MeHg in eggs from fish fed the same diet throughout the experiment varied with MeHg content of the maternal diet and were related positively to levels in the carcass of the maternal fish. However, MeHg in eggs was not proportional to that in carcasses among dietary treatments; MeHg in eggs from adults fed the control, low, medium, and high MeHg diets averaged 14%, 25%, 32%, and 35% of that in adults. For fish fed the control diet as juveniles and MeHg-contaminated diets after reaching sexual maturity, MeHg in eggs increased rapidly with duration of maternal dietary exposure prior to spawning. Moreover, concentrations of MeHg in eggs from fish fed the same contaminated diet as both juveniles and sexually mature adults were not related to the duration of adult exposure, and they were not appreciably greater than those from fish fed contaminated diets only just priorto spawning. These results indicate that the diet of the maternal adult during oogenesis, and not adult body burden, is the principal source of MeHg in fish eggs. Accordingly, the exposure of embryonic wild fishes to MeHg depends on levels of the contaminant in prey of the adult during oogenesis, which can vary intra- and interannually.

Animals↗

Pfiesteria shumwayae kills fish by micropredation not exotoxin secretion.

Pfiesteria piscicida and P. shumwayae reportedly secrete potent exotoxins thought to cause fish lesion events, acute fish kills and human disease in mid-Atlantic USA estuaries. However, Pfiesteria toxins have never been isolated or characterized. We investigated mechanisms by which P. shumwayae kills fish using three different approaches. Here we show that larval fish bioassays conducted in tissue culture plates fitted with polycarbonate membrane inserts exhibited mortality (100%) only in treatments where fish and dinospores were in physical contact. No mortalities occurred in treatments where the membrane prevented contact between dinospores and fish. Using differential centrifugation and filtration of water from a fish-killing culture, we produced 'dinoflagellate', 'bacteria' and 'cell-free' fractions. Larval fish bioassays of these fractions resulted in mortalities (60-100% in less than 24 h) only in fractions containing live dinospores ('whole water', 'dinoflagellate'), with no mortalities in 'cell-free' or 'bacteria'-enriched fractions. Videomicrography and electron microscopy show dinospores swarming toward and attaching to skin, actively feeding, and rapidly denuding fish of epidermis. We show here that our cultures of actively fish-killing P. shumwayae do not secrete potent exotoxins; rather, fish mortality results from micropredatory feeding.

Animals↗