Showing papers by "National University of La Plata published in 1996"
TL;DR: The results presented here strongly suggest that casein is the major allergenic component of cow's milk.
Abstract: The objective of this study was to analyze both the allergenicity and immunogenicity of cow's milk proteins. To this end, 80 milk-atopic patients were selected on the basis of the presence of cow's milk-specific IgE antibodies in serum and compatible clinical history. Fifteen patients allergic to other allergens and 10 nonatopic subjects were studied as controls. The specificity of serum IgG and IgE antibodies was determined by immunoblotting, employing both cow's milk and milk components, i.e., alpha- and beta-casein, beta-lactoglobulin, and alpha-lactalbumin separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The experiments showed that casein-specific IgE antibodies were present in all (80/80) sera examined; 10/80 showed reactivity to beta-lactoglobulin, and 5/80 showed reactivity to alpha-lactalbumin. None of the 25 negative control sera analyzed showed the presence of specific IgE antibodies against milk proteins. These results were similar to those corresponding to the detection, by the radioallergosorbent test, of IgE antibodies against the milk components coupled to paper disks. All sera from milk-atopic patients also showed IgE reactivity against a high-molecular-mass fraction that hardly enters the gel. This fraction, after separation by gel filtration and treatment with beta-mercaptoethanol and urea, was shown by SDS-PAGE analysis to be formed by casein monomers. All sera analyzed by immunoblotting reacted against the components corresponding to casein monomers. Inhibition of immunoblotting by adsorption with different milk components confirmed that those high-molecular-mass aggregates are formed by casein components. The results presented here strongly suggest that casein is the major allergenic component of cow's milk.
193 citations
TL;DR: The data show that acidosis can alter the phosphorylation of these two proteins and suggest that these changes underlie, in part the changes observed in cardiac muscle during acidosis.
Abstract: Acidosis inhibits Ca2+ transport by the sarcoplasmic reticulum of cardiac muscle and decreases the Ca2+ sensitivity of the contractile proteins, although the mechanisms underlying these changes are...
167 citations
TL;DR: In this article, the authors presented two a-posteriori error estimators for elliptic partial differential equations, when they use a mixed method, one is based on an adequate evaluation of the residual of the finite element solution and the other on the solution of a local problem.
Abstract: We present two a-posteriori error estimators for elliptic partial differential equations, when we use a mixed method. One is based on a adequate evaluation of the residual of the finite element solution and the other on the solution of a local problem. We prove their equivalence with the norm of the error, when the data is locally smooth.
152 citations
TL;DR: Amaranth protein isolates were prepared by extraction at different alkaline pHs and precipitation at pH 5 and (b) extraction at pH 9, 10, and 11, albumin-1 and glutelin were also present as discussed by the authors.
Abstract: Amaranth protein isolates were prepared by (a) extraction at different alkaline pHs and precipitation at pH 5 and (b) extraction at pH 9 and precipitation at different pHs. The isolates were compared with protein fractions. DSC analysis showed that albumin-1 was composed of several species of Td below 80 °C and ΔH below 4.0 J/g. Glutelin had two species of different Td. Both, globulin and albumin-2, had a main component of Td of 94 °C and ΔH of 19.7 ± 3.2 J/g. The thermal behavior and composition of isolates prepared by method a depended on the extraction pH. The isolate extracted at pH 8 was mainly composed of albumin-1 and globulin, whereas at pHs 9, 10, and 11, albumin-2 and glutelin were also present. The increase of the extraction pH led to a decrease in the thermal stability of proteins from pH 8 on and to a decrease in ΔH at pH 11. With method b, different isolates were obtained. At pH 6 and 7, most of the albumin-2 and some of the globulins precipitated, whereas at pHs 4 and 5, all protein fractio...
140 citations
TL;DR: The data obtained clearly indicate a highly significant increase in the frequency of MN and of trisomy in lymphocytes from exposed children and women in comparison with controls, but no notable effects were found on the frequencies of SCEs, specific translocations, or on cell cycle progression.
Abstract: For conducting an adequate human cancer risk assessment of inorganic arsenic (As) in the low-dose region, it is important to establish its mode of action. In this context, the nature of genotoxic effects induced by this agent is of considerable interest. However, the results from such investigations in human have been conflicting. In an attempt to resolve this issue, the clastogenic and aneugenic potential of As was investigated in women and children from native population exposed to high levels (around 0.2 mg/l) of natural As via drinking water in San Antonio de los Corbes in the Andean region of Salta, Northwestern Argentina. The water did not contain elevated levels of heavy metals, such as lead or cadmium, nor was the investigated population exposed to significant industrial pollution or to pesticides. An ethnically similar control group from Rosario de Lerma, Salta, where only extremely low concentration of arsenic in drinking water could be detected, was used as a control. To evaluate the genotoxic effects in peripheral blood lymphocytes, micronuclei (MN) in binucleated cells, sister-chromatid exchanges (SCEs) and the fluorescence in situ hybridization technique (FISH) in combination with chromosome specific DNA libraries were employed. The data obtained clearly indicate a highly significant increase in the frequency of MN and of trisomy in lymphocytes from exposed children and women in comparison with controls, but no notable effects were found on the frequencies of SCEs, specific translocations, or on cell cycle progression. As supported by FISH analysis, at least a proportion of MN appears to originate from whole chromosome loss. An additional finding was the unusually low background levels of MN in unexposed individuals from this ethnic group as compared to other populations, e.g., Caucasians.
112 citations
TL;DR: Overall, imperfect fungi isolated from polluted soils showed a somewhat higher efficiency, but the performance of unadapted, indigenous, lignolitic fungi was comparable, and all three species, Pleurotus ostreatus, Trametes villosus and Coriolopsis rigida, effectively degraded aliphatic and aromatic components.
104 citations
TL;DR: In this article, the RXTE/PCA observations of the black hole candidate Cygnus X-1 indicate that the source did not enter a high state like the one observed in black hole transients, but instead was in an intermediate state similar to what has been observed in GS 1124-68 and GX 339-4.
Abstract: We report RXTE/PCA observations of the black hole candidate Cygnus X-1. In 1996 February the source was in its usual "low" state. In three observations during 1996 May the source was on average brighter by a factor of 2 and showed less rapid variability and a softer energy spectrum. However, the observations indicate that Cyg X-1 did not enter a high state like the one observed in black hole transients. Flux, variability, and spectral shape suggest instead that the source was in an "intermediate" state similar to what has been observed in GS 1124-68 and GX 339-4. Perhaps also the state transitions of Cyg X-1 observed in the 1970s were not to a high state but to this intermediate state.
104 citations
TL;DR: The results indicate that cAMP- (Ser16) and Ca2+-calmodulin (Thr17)-dependent pathways of phospholamban phosphorylation can occur independently of each other.
104 citations
TL;DR: In this article, the vertical fluxes averaged 7.2, 3.1 and 0.8 mg m−2 d−1, respectively, at landward and seaward sites in the Laurentian Trough.
88 citations
TL;DR: The effect of exogenously applied gibberellic acid (GA3) on the postharvest color change of strawberry fruit was evaluated through their external color and surface color parameters and a significant delay on color evolution was observed.
Abstract: The effect of exogenously applied gibberellic acid (GA3) on the postharvest color change of strawberry fruit was evaluated through their external color and surface color parameters. A significant delay on color evolution was observed in fruits treated with GA3. The evolution of activities of phenylalanine ammonia-lyase (PAL), chlorophyllase, and peroxidase was also analyzed. PAL activity increased during strawberry ripening, but in fruits treated with GA3 the increase in such activity was slower, and, probably as consequence, the development of red color was delayed. Moreover, the activity of chlorophyllase and peroxidase, enzymes possibly involved in chlorophyll metabolism, decreased during strawberry ripening. However, a delay was observed in the decrease of such activities in GA3-treated fruits.
83 citations
TL;DR: It is found that the hydrophilic wall induces strong ordering near its surface, but such order is present only up to about two molecular diameters away from it, and on the other hand, the Hydrophobic wall induces a slight ordering, but this ordering remains for several molecular diameter inside the bulk.
Abstract: This work was aimed at contrasting the properties of water near highly hydrophilic or highly hydrophobic walls. We performed molecular dynamics computer simulations of two systems, both composed of a number of water molecules together with a layer of either purely hydrophilic or purely hydrophobic molecules restrained in mobility so as to form walls. Simulations were done at constant temperature and at constant volume or constant pressure. We found that the hydrophilic wall induces strong ordering near its surface, but such order is present only up to about two molecular diameters away from it. On the other hand, the hydrophobic wall induces a slight ordering, but this ordering remains for several molecular diameters inside the bulk.
TL;DR: In this paper, the authors proposed bootstrap tests for unit roots in first-order autoregressive models and established their asymptotic validity both for independent and for auto-regression errors.
Abstract: SUMMARY We propose bootstrap tests for unit roots in first-order autoregressive models and we establish their asymptotic validity both for independent and for autoregressive errors; in this case, the bootstrap methodology directly approaches the asymptotic distribution, making unnecessary the usual corrections due to dependence of innovations. We also present a Monte Carlo power study comparing these tests with existing alternative methods. For small samples, the power of the bootstrap test outperforms that of previous proposals.
TL;DR: It is shown that this arrow of time is related to symmetries of the Fokker-Planck equation and it is given here a concrete illustration of Frieden's bow of time connected with Fisher's information measure.
Abstract: We give here a concrete illustration of Frieden's arrow of time, connected with Fisher's information measure. It is shown that this arrow of time is related to symmetries of the Fokker-Planck equation. \textcopyright{}1996 The American Physical Society.
TL;DR: In this paper, changes in the structure and functional properties of soy protein isolates caused by mild acid treatment at room temperature were investigated, and different conditions (pH, time, neutralization procedure, and isolate concentration) of acid treatment and consequent salt increase were analyzed.
Abstract: In the present work, changes in the structure and functional properties of soy protein isolates caused by mild acid treatment at room temperature were investigated. Different conditions (pH, time, neutralization procedure, and isolate concentration) of acid treatment and consequent salt increase were analyzed. The results obtained show that there is a selective denaturation of 11S protein, which conduces to higher surface hydrophobicity. The solubility of modified isolates decreases with extended storage period of the flour from which they were obtained and with higher isolate concentration during acid treatment. The high water imbibing capacity (WIC) of the resulted insoluble fraction does not produce significant changes in the WIC of the total isolate. The denaturation and dissociation of 11S protein lead to modified isolates with improved capacity to form and to stabilize foams without losing the gel formation capacity. Keywords: Soy protein; soy isolate; chemical modification; acid treatment; thermal ...
TL;DR: The findings indicate that lemon grass and thyme oils could be used as effective inhibitors of AFB in honey bee colonies.
Abstract: Essential oils from savory (Satureja hortensis), lavandin (Lavandula hybrida), eucalyptus (Eucalyptus globulus), lemon grass (Cymbopogon citratus), peppermint (Mentha × piperita), oregano (Origanum vulgare), rosemary (Rosmarinus officinalis), and thyme (Thymus vulgaris) were tested for antimicrobial activities against Paenibacillus larvae, the causal agent of American Foulbrood Disease (AFB) of honey bees. Trials for determining the minimum inhibitory concentration (MIC) of these oils revealed that lemon grass and thyme were the most effective with MIC values between 50 to 100 $mUl/liter and 100 to 150μl/liter, respectively, in tests with 8 Paenibacillus larvae strains from different Argentinean geographical regions. The findings indicate that lemon grass and thyme oils could be used as effective inhibitors of AFB in honey bee colonies.
TL;DR: In this article, the effects of aging time (6 to 21 d at 4°C), ripening before or after freezing, freezing rate, and frozen storage (3 mo at −20°C) on characteristics of low moisture Mozzarella cheese were assessed.
TL;DR: An archetype model for the collective displacements of self-driven individuals, aimed to describe dynamic of flocking behavior among living things, is presented and studied and shows that systems rule the model self-organize into a critical state exhibiting power-law behavior in both the distribution population avalanches and the spatial correlation between individuals.
Abstract: An archetype model for the collective displacements of self-driven individuals, aimed to describe the dynamic of flocking behavior among living things, is presented and studied. Processes such as growth, death, survival, self-propagation, and competition are considered. It is shown that systems ruled by the model self-organize into a critical state exhibiting power-law behavior in both the distribution of population avalanches and the spatial correlation between individuals.
TL;DR: In this paper, the role of free radicals in relation to ethylene production during ageing of cut carnation petals was studied, and the results showed that after 6 d of cutting, the efflux of electrolytes increased 101% and 2,7-dichlorofluorescein oxidation rate increased 53% from day 8 to day 11 after detachment.
Abstract: The objective of this work was to study the role of free radicals in relation to ethylene production during ageing of cut carnation petals. Ethylene production by freshly cut flowers was negligible, but 8 d after cutting ethylene production began to increase and reached a peak by day 9, before beginning to decline again. The efflux of electrolytes (membrane damage index) increased 101% and 2 ,7-dichlorofluorescein oxidation rate (oxidative stress index) increased 53% from day 8 to day 11 after detachment. Ethylene peak was either (a) not affected significantly by the supplementation of exogenous ethylene on the day of cutting, or (b) expanded between days 7-9 after ethylene supplementation on day 6 of cutting, or (c) was inhibited by amino-oxyacetic acid and paraquat treatments. After ethylene supplementation, conductivity and 2,7-dichlorofluorescein oxidation increased significantly as compared to control petals, and the activity of antioxidant enzymes was not affected. However, both w-tocopherol and glutathione content decreased significantly after ethylene supplementation on day 6 after detachment. Amino-oxyacetic acid treatment prevented the increases in conductivity and 2,7dichlorofluorescein oxidation, did not alter the activities of antioxidant enzymes and significantly increased the content of a-tocopherol and glutathione as compared to control carnation petals. Paraquat treatment paralleled qualitatively ethylene supplementation after 6 d of cutting. Taken as a whole, the data presented here may be understood as experimental evidence of a close association between ethylene production and oxidative stress in ageing of cut carnations.
TL;DR: The addition of calcium (1.23−9.73 mg/g of protein) during neutralization of isoelectric precipitate modified the thermal behavior of soybean protein isolates.
Abstract: The addition of calcium (1.23−9.73 mg/g of protein) during neutralization of isoelectric precipitate modified the thermal behavior of soybean protein isolates. In the samples that did not undergo thermal treatment, the calcium content increase caused an increase in thermal stability, especially in the 11S fraction, but no modifications were detected in the enthalpy values. Samples undergoing mild thermal treatments (5 min at 80 °C), after neutralization with different amounts of calcium, showed enthalpy values lower than those of the unheated samples. Isolates with no calcium aggregates or with values below 5 mg/g of protein and intense thermal treatment (15 min at 90 °C) showed no endotherms (denaturation enthalpies = 0). Calcium levels above 5 mg/g of protein protected the soybean proteins, partially preventing their denaturation by heating at 90 °C for 15 min. The activation energy of the thermal denaturation process of soybean protein isolates, calculated by the Ozawa method (1970), was modified in th...
TL;DR: In this paper, visual, manual and oral texture descriptors for Reggianito grating cheese were correlated with parameters obtained from an instrumental compression test, and linear partial least squares regression was used for the multivariate correlations and proved to be a useful tool.
TL;DR: In Patagonia a Triassic-Early Jurassic Cordilleran interior magmatic belt preceded the widespread eruption of Middle Jurassic syn-extensional rhyolites, and two plutons (La Calandria and La Leona) represent the easternmost plutonic rocks of this belt, > 750 km east of the present oceanic trench as mentioned in this paper.
Abstract: In Patagonia a Triassic-Early Jurassic Cordilleran interior magmatic belt preceded the widespread eruption of Middle Jurassic syn-extensional rhyolites. Two plutons (La Calandria and La Leona) represent the easternmost plutonic rocks of this belt, > 750 km east of the present oceanic trench. They define a high-K calc-alkaline monzonite series in contrast with the main Andinotype arc magmatism of the Pacific margin: they are enriched in large ion lithophile elements (K, Rb, Ba, Sr and Th), LREE and P2O5 and depleted in HREE and Y, with low FeO*/MgO ratio. The range of observed compositions (56-76% SiO2) resulted from high-level fractionation of plagioclase, hornblende, biotite, K-feldspar and accessories (sphene, apatite and zircon).
Initial 87Sr/86Sr ratios, average eNdt and mean depleted-mantle Nd model ages of the two plutons are 0·70487, -0·5 and 1050 Ma for La Calandria and 0·70509, -1·4 and 1125 Ma for La Leona, respectively. They are thus isotopically more primitive than the Middle Jurassic rhyolites, previously attributed to partial melting of Mesoproterozoic mafic lower crust. The preferred model for the origin of the monzonites is remelting of an amphibole- + garnet-bearing, plagioclase-poor, high-K mafic source (?underplating). This occurred in a distal sector of a dying oblique subduction regime, immediately preceding the extensional silicic volcanism.
TL;DR: In this article, the thermal stability of soybean protein isolates was studied by differential scanning calorimetry and it was shown that 11S globulin had higher activation energy for denaturation process than did 7S Globulin.
Abstract: pH-induced modifications in the thermal stability of soybean protein isolates were studied by differential scanning calorimetry. The thermal stability of the 11S globulin was higher than that of the 7S globulin and was very sensitive to pH changes. The glycinin denaturation temperature decreased by 10 °C when the pH was increased from 6 to 11, while the 7S globulin denaturation temperature did not change. At pH 11, soybean isolate gave only one endotherm representing both globulins. 11S globulin underwent conformational changes as the pH increased, which were reflected by lower cooperativity in the denaturation process. 11S globulin also had a higher activation energy for the denaturation process than did 7S globulin. The activation energy of 11S globulin was higher than that of 7S globulin (in the pH 6−10 range) and shows a maximum kinetic stability at pH 8. The 7S and 11S globulin half-lives at different treatment temperatures were calculated to pHs between 6 and 11, and thermal treatments causing diffe...
TL;DR: In this article, pressure drops were measured in clean wheat beds for superficial air velocities up to 0·42 m/s at grain moisture contents in the range of 12·8-22·3% wb.
Abstract: The behaviour of Ni supported catalysts, obtained using Ni(NO3)2 and Ni-acetylacetonate as precursor compounds, is analyzed It is observed that initial activities and selectivities are similar for both systems, but the stability differs significantly The systems show different carbon structures and sintering rates, depending on the precursor compound employed
TL;DR: Solid-state cultures of a pectinase-producing fungus (Aspergillus foetidus NRRL 341) were performed under different acidic conditions, finding that the higher the acidity, the lower the pectinesterase activity and the higher both the polymethylgalacturonate lyase and polyGalacturonase activities.
Abstract: Solid-state cultures of a pectinase-producing fungus (Aspergillus foetidus NRRL 341) were performed under different acidic conditions. Glass bottles containing 5 g of wheat bran and 7.5 mL of 0.2, 0.3, 0.4, or 0.5 N HCl were autoclaved (15 min, 121°C), inoculated with a spore suspension appropriately diluted to achieve an initial concentration of 4 × 104 spores per gram of wet substrate (with a 60 % humidity, on wet basis) and incubated at 30°C. Time course of pH and of different pectinase activities were determined in culture extracts. Total pectinase activity (TPA), expressed in terms of viscosimetric units per gram of wet substrate (VU.g−1), was affected by the initial culture acidity. The higher the HCl concentration used, the higher the TPA achieved, but after longer cultivation times. On the other hand, when 0.5 HCl was used, no fungal growth was observed. Nevertheless, enzyme productivity increased with culture acidity. When 0.4 HCl was used, TPA reached its maximum after 36 h of cultivation (2,535 VU.g−1). With 0.2 and 0.3 N HCl, TPA was the highest at 24 h (733 VU.g−1) and at 30 h (1,860 VU.g−1) respectively. The composition of the pectinase pool was also affected by culture acidity. The higher the acidity, the lower the pectinesterase activity and the higher both the polymethylgalacturonate lyase and polygalacturonase activities.
TL;DR: It is suggested that membrane depolarization during cardiac action potential causes an increase in electrogenic Na(+)-HCO3- cotransport, which would substantially increase the myocardial cell's ability to recover from an enhanced proton production.
Abstract: The contribution of electrogenic Na(+)-HCO3- cotransport to pHi regulation during changes in heart rate was explored in cat papillary muscles loaded with BCECF-AM in bicarbonate-free (HEPES) medium and in CO2/HCO3(-)-buffered medium Stepwise increments in the frequency of contraction from 15 to 100 bpm induced a reversible increase in the pHi from 713 +/- 003 to 736 +/- 003 (P < 05, n = 5) in the presence of CO2/ HCO3- buffer The same increase in the frequency of stimulation, however, decreased pHi from 710 +/- 002 to 691 +/- 006 (P < 05, n = 5), in the absence of bicarbonate Moreover, in CO2/HCO3(-)-superfused muscles pretreated with SITS (01 mmol/L), this effect of increasing the contraction frequency was reversed, and a decrease of pHi from 703 +/- 004 to 688 +/- 006 (P < 05, n = 4) was observed when the pacing rate was increased stepwise from 15 to 100 bpm High [K+]o-induced depolarization of cell membrane alkalinized myocardial cells in the presence of HCO3- ions, whereas acidification was observed as a consequence of hyperpolarization induced by low external [K+]o Myocardial resting membrane potential became hyperpolarized upon exposure to HCO3(-)-buffered media This HCO3(-)-induced hyperpolarization was not blocked by the inhibition of Na+,K(+)-ATPase activity by ouabain (05 mumol/L) but was prevented by SITS The results suggested that membrane depolarization during cardiac action potential causes an increase in electrogenic Na(+)-HCO3- cotransport Such depolarizations occurring as a consequence of increases in heart rate would thus, by means of elevated bicarbonate influxes, substantially increase the myocardial cell's ability to recover from an enhanced proton production
TL;DR: It is suggested that low and repeated doses of mycotoxins, necessary to produce a subclinical intoxication, precipitate Toxoplasma cyst rupture and consequently the activation of chronic toxoplasmosis.
TL;DR: Three lipoproteins and one lipoprotein fraction were detected for the first time in gastropods and are probably the major supply of lipids and amino acids for the developing embryo.
Abstract: The lipid and protein composition of the perivitelline fluid of the eggs of Pomacea canaliculata was investigated. Two lipoproteins (PV 1 and PV 2) and one lipoprotein fraction (PV 3) were detected for the first time in gastropods. They represent 57.0, 7.5, and 35.5% of the egg total proteins, respectively.
PV 1 is a glyco-carotene-protein complex with characteristics of a very high-density lipoprotein (VHDL). It has 0.33% lipids, mainly free sterols and phospholipids. The particle has a MW of 300 Kd and is composed of three subunits of 35, 32, and 28 Kd, respectively.
PV 2 particle is a VHDL of 400 Kd and 3.75% lipids. The major lipid classes are free sterols and phospholipids and also have significant quantities of energy-providing triacylglycerides and free fatty acids. It is composed of two apoproteins of 67 and 31 Kd.
PV 3 density corresponds to a high-density lipoprotein (HDL). It was fractionated into two subfractions “h” and “p”. Fraction “h” contains 5.16% lipids, mainly free sterols, phospholipids, and free fatty acids, and two particles of 100 and 64 Kd. Dissociating electrophoresis showed two subunits of 34 and 29 Kd. Fraction “p” is composed of a single particle of 26 Kd that contains 9.5% lipids, which represents 30% of the total egg lipids. It has high levels of a carotenoid pigment. Besides it contains free fatty acids, hydrocarbons, sterified sterols, and triacylglycerides. These three fractions are probably the major supply of lipids and amino acids for the developing embryo. © 1996 Wiley-Liss, Inc.
TL;DR: In this article, the authors discuss the (2 + 1)-dimensional Abelian Higgs model coupled to N = 2 supergravity and provide an example on how unbroken supercharges can be defined, circumventing the problem of finding supercovariantly constant Killing spinors in 2+1 dimensions.
TL;DR: One hundred four out of 225 diagnosticated cases were myxosporidian, monogenean, Ichthyophthirius multifiliis Fouquet, 1876 and bacterial diseases in Piaractus mesopotamicus Holmberg, 1887, Colossoma macropomum Cuvier, 1818 and tambacu, at Aquaculture Center, Universidade Estadual Paulista, Jaboticabal, Sao Paulo, Brazil, between 1992 and 1995.
Abstract: One hundred four out of 225 diagnosticated cases were myxosporidian, monogenean, Ichthyophthirius multifiliis Fouquet, 1876 and bacterial diseases in Piaractus mesopotamicus Holmberg, 1887 (pacu), Colossoma macropomum Cuvier, 1818 (tambaqui) and tambacu, at Aquaculture Center, Universidade Estadual Paulista (UNESP), Jaboticabal, Sao Paulo, Brazil, between 1992 and 1995. The gills were fixed in 10% buffered formalin solution to posterior histologic routine. It was observed Henneguya sp. cysts into the capillaries of the secondary lamellae, encapsulated by the respiratory epithelium cells. It provoked adherence of the adjacent lamellae, hyperplasia, congestion, oedema and epithelium displacement. Monogeneans infestations by Anacanthorus penilabiatus Boeger, Husak & Martins, 1995 and Ancyrocephalinae sub-family caused light inflammatory reaction and hyperplasia. In severe infestations was observed hyperplasia of primary lamellae, necrosis, oedema, respiratory epithelium displacement, ruptured pillar cells and telangiectasis. Response to I. multifiliis was limited to surrounding epithelial cells in young fishes and hyperplasia, necrosis, inflammatory infiltrate and oedema in old fishes. Such lesions iniciate hyperplasic and oedematous process that with inflammation of the parasitic sites, provoked alterations over gases and ions interchange surface and consequently fish metabolism.