99 resultados para Free-living protozoa
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Fish meal free diets were formulated to contain graded protein levels as 25% (diet 1), 30% (diet 2), 35% (diet 3) and 40% (diet 4). The diets were fed to tambaqui juveniles (Colossoma macropomum) (46.4 ± 6.3g) in randomly designed recirculating systems for 60 days, to determine the optimum protein requirement for the fish. The final weight of the fish, weight gain (28.1, 28.5, 32.2, 28.0g) and specific growth rate increased (P>0.05) consistently with increasing dietary protein up to treatment with 35% protein diet and then showed a declining trend. Feed intake followed the same trend resulting in best feed efficiency (62.5%) in fish fed diet with 35% protein. Similarly, the protein intake increased significantly with increasing dietary protein levels and reduced after the fish fed with 35% protein; while protein efficiency ratio (2.28, 1.99, 1.87, 1.74) decreased with increasing dietary protein levels. Carcass ash and protein had linear relationship with dietary protein levels while the lipid showed a decreasing trend. Ammonia content (0.68, 0.73, 0.81, 1.21 mg L-1) of the experimental waters also increased (P<0.05) with increasing protein levels while pH, dissolved oxygen and temperature remained fairly constant without any clear pattern of inclination. Broken-line estimation of the weight gain indicated 30% protein as the optimum requirement for the fish.
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Objective: The objective of this article was to investigate the biopsychosocial factors that influence adherence to treatment and the quality of life of individuals who have been successfully following the HIV/AIDS treatment. Methods: It is a cross-sectional study carried out with 120 HIV positive participants in the south of Brazil. Among the variables studied, of note are: perceived stress, social support, symptoms of anxiety and depression and quality of life. Results: The results show that a moderate to high adherence to the treatment paired with a strong sense of social support indicate a higher quality of life. Conclusion: The combination of social support and antiretroviral treatment have an impact on physical conditions, improving immune response and quality of life.
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FUNDAMENTO: O Minnesota Living with Heart Failure Questionnaire (MLHFQ) é uma importante ferramenta de avaliação da qualidade de vida em pacientes com insuficiência cardíaca. Apesar de amplamente usado em nosso meio, não contávamos com a sua tradução e validação em língua portuguesa. OBJETIVO: Este estudo pretendeu traduzir e validar a versão em português do MLHFQ em pacientes com insuficiência cardíaca. MÉTODOS: Quarenta pacientes com insuficiência cardíaca (30 homens, FEVE 30±6%, 55% de etiologia isquêmica, NYHA I a III) com estabilidade clínica e terapia medicamentosa otimizada realizaram teste cardiopulmonar máximo para avaliação da capacidade física. Logo após, o MLHFQ, devidamente traduzido, foi aplicado por um mesmo pesquisador. A classe funcional NYHA foi encaminhada pela equipe medica. RESULTADOS: A versão em português do MLHFQ apresentou-se com a mesma estrutura e métrica da versão original. Não houve dificuldade na aplicação e compreensão do questionário por parte dos pacientes. A versão em português do MLHFQ mostrou-se concordante com o pico de VO2, o tempo de exercício do teste cardiopulmonar e com a classificação funcional da NYHA. Não houve diferença da média do escore do questionário entre os grupos de etiologia isquêmica e não-isquêmica. CONCLUSÃO: A versão em língua portuguesa da MLHFQ, proposta no presente estudo, demonstrou ser válida em pacientes com insuficiência cardíaca, constituindo uma nova e importante ferramenta para avaliar a qualidade de
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In thee present paper the classical concept of the corpuscular gene is dissected out in order to show the inconsistency of some genetical and cytological explanations based on it. The author begins by asking how do the genes perform their specific functions. Genetists say that colour in plants is sometimes due to the presence in the cytoplam of epidermal cells of an organic complex belonging to the anthocyanins and that this complex is produced by genes. The author then asks how can a gene produce an anthocyanin ? In accordance to Haldane's view the first product of a gene may be a free copy of the gene itself which is abandoned to the nucleus and then to the cytoplasm where it enters into reaction with other gene products. If, thus, the different substances which react in the cell for preparing the characters of the organism are copies of the genes then the chromosome must be very extravagant a thing : chain of the most diverse and heterogeneous substances (the genes) like agglutinins, precipitins, antibodies, hormones, erzyms, coenzyms, proteins, hydrocarbons, acids, bases, salts, water soluble and insoluble substances ! It would be very extrange that so a lot of chemical genes should not react with each other. remaining on the contrary, indefinitely the same in spite of the possibility of approaching and touching due to the stato of extreme distension of the chromosomes mouving within the fluid medium of the resting nucleus. If a given medium becomes acid in virtue of the presence of a free copy of an acid gene, then gene and character must be essentially the same thing and the difference between genotype and phenotype disappears, epigenesis gives up its place to preformation, and genetics goes back to its most remote beginnings. The author discusses the complete lack of arguments in support of the view that genes are corpuscular entities. To show the emharracing situation of the genetist who defends the idea of corpuscular genes, Dobzhansky's (1944) assertions that "Discrete entities like genes may be integrated into systems, the chromosomes, functioning as such. The existence of organs and tissues does not preclude their cellular organization" are discussed. In the opinion of the present writer, affirmations as such abrogate one of the most important characteristics of the genes, that is, their functional independence. Indeed, if the genes are independent, each one being capable of passing through mutational alterations or separating from its neighbours without changing them as Dobzhansky says, then the chromosome, genetically speaking, does not constitute a system. If on the other hand, theh chromosome be really a system it will suffer, as such, the influence of the alteration or suppression of the elements integrating it, and in this case the genes cannot be independent. We have therefore to decide : either the chromosome is. a system and th genes are not independent, or the genes are independent and the chromosome is not a syntem. What cannot surely exist is a system (the chromosome) formed by independent organs (the genes), as Dobzhansky admits. The parallel made by Dobzhansky between chromosomes and tissues seems to the author to be inadequate because we cannot compare heterogeneous things like a chromosome considered as a system made up by different organs (the genes), with a tissue formed, as we know, by the same organs (the cells) represented many times. The writer considers the chromosome as a true system and therefore gives no credit to the genes as independent elements. Genetists explain position effects in the following way : The products elaborated by the genes react with each other or with substances previously formed in the cell by the action of other gene products. Supposing that of two neighbouring genes A and B, the former reacts with a certain substance of the cellular medium (X) giving a product C which will suffer the action, of the latter (B). it follows that if the gene changes its position to a place far apart from A, the product it elaborates will spend more time for entering into contact with the substance C resulting from the action of A upon X, whose concentration is greater in the proximities of A. In this condition another gene produtc may anticipate the product of B in reacting with C, the normal course of reactions being altered from this time up. Let we see how many incongruencies and contradictions exist in such an explanation. Firstly, it has been established by genetists that the reaction due.to gene activities are specific and develop in a definite order, so that, each reaction prepares the medium for the following. Therefore, if the medium C resulting from the action of A upon x is the specific medium for the activity of B, it follows that no other gene, in consequence of its specificity, can work in this medium. It is only after the interference of B, changing the medium, that a new gene may enter into action. Since the genotype has not been modified by the change of the place of the gene, it is evident that the unique result we have to attend is a little delay without seious consequence in the beginning of the reaction of the product of B With its specific substratum C. This delay would be largely compensated by a greater amount of the substance C which the product of B should found already prepared. Moreover, the explanation did not take into account the fact that the genes work in the resting nucleus and that in this stage the chromosomes, very long and thin, form a network plunged into the nuclear sap. in which they are surely not still, changing from cell to cell and In the same cell from time to time, the distance separating any two genes of the same chromosome or of different ones. The idea that the genes may react directly with each other and not by means of their products, would lead to the concept of Goidschmidt and Piza, in accordance to which the chromosomes function as wholes. Really, if a gene B, accustomed to work between A and C (as for instance in the chromosome ABCDEF), passes to function differently only because an inversion has transferred it to the neighbourhood of F (as in AEDOBF), the gene F must equally be changed since we cannot almH that, of two reacting genes, only one is modified The genes E and A will be altered in the same way due to the change of place-of the former. Assuming that any modification in a gene causes a compensatory modification in its neighbour in order to re-establich the equilibrium of the reactions, we conclude that all the genes are modified in consequence of an inversion. The same would happen by mutations. The transformation of B into B' would changeA and C into A' and C respectively. The latter, reacting withD would transform it into D' and soon the whole chromosome would be modified. A localized change would therefore transform a primitive whole T into a new one T', as Piza pretends. The attraction point-to-point by the chromosomes is denied by the nresent writer. Arguments and facts favouring the view that chromosomes attract one another as wholes are presented. A fact which in the opinion of the author compromises sereously the idea of specific attraction gene-to-gene is found inthe behavior of the mutated gene. As we know, in homozygosis, the spme gene is represented twice in corresponding loci of the chromosomes. A mutation in one of them, sometimes so strong that it is capable of changing one sex into the opposite one or even killing the individual, has, notwithstading that, no effect on the previously existing mutual attraction of the corresponding loci. It seems reasonable to conclude that, if the genes A and A attract one another specifically, the attraction will disappear in consequence of the mutation. But, as in heterozygosis the genes continue to attract in the same way as before, it follows that the attraction is not specific and therefore does not be a gene attribute. Since homologous genes attract one another whatever their constitution, how do we understand the lack cf attraction between non homologous genes or between the genes of the same chromosome ? Cnromosome pairing is considered as being submitted to the same principles which govern gametes copulation or conjugation of Ciliata. Modern researches on the mating types of Ciliata offer a solid ground for such an intepretation. Chromosomes conjugate like Ciliata of the same variety, but of different mating types. In a cell there are n different sorts of chromosomes comparable to the varieties of Ciliata of the same species which do not mate. Of each sort there are in the cell only two chromosomes belonging to different mating types (homologous chromosomes). The chromosomes which will conjugate (belonging to the same "variety" but to different "mating types") produce a gamone-like substance that promotes their union, being without action upon the other chromosomes. In this simple way a single substance brings forth the same result that in the case of point-to-point attraction would be reached through the cooperation of as many different substances as the genes present in the chromosome. The chromosomes like the Ciliata, divide many times before they conjugate. (Gonial chromosomes) Like the Ciliata, when they reach maturity, they copulate. (Cyte chromosomes). Again, like the Ciliata which aggregate into clumps before mating, the chrorrasrmes join together in one side of the nucleus before pairing. (.Synizesis). Like the Ciliata which come out from the clumps paired two by two, the chromosomes leave the synizesis knot also in pairs. (Pachytene) The chromosomes, like the Ciliata, begin pairing at any part of their body. After some time the latter adjust their mouths, the former their kinetochores. During conjugation the Ciliata as well as the chromosomes exchange parts. Finally, the ones as the others separate to initiate a new cycle of divisions. It seems to the author that the analogies are to many to be overlooked. When two chemical compounds react with one another, both are transformed and new products appear at the and of the reaction. In the reaction in which the protoplasm takes place, a sharp difference is to be noted. The protoplasm, contrarily to what happens with the chemical substances, does not enter directly into reaction, but by means of products of its physiological activities. More than that while the compounds with Wich it reacts are changed, it preserves indefinitely its constitution. Here is one of the most important differences in the behavior of living and lifeless matter. Genes, accordingly, do not alter their constitution when they enter into reaction. Genetists contradict themselves when they affirm, on the one hand, that genes are entities which maintain indefinitely their chemical composition, and on the other hand, that mutation is a change in the chemica composition of the genes. They are thus conferring to the genes properties of the living and the lifeless substances. The protoplasm, as we know, without changing its composition, can synthesize different kinds of compounds as enzyms, hormones, and the like. A mutation, in the opinion of the writer would then be a new property acquired by the protoplasm without altering its chemical composition. With regard to the activities of the enzyms In the cells, the author writes : Due to the specificity of the enzyms we have that what determines the order in which they will enter into play is the chemical composition of the substances appearing in the protoplasm. Suppose that a nucleoproteln comes in relation to a protoplasm in which the following enzyms are present: a protease which breaks the nucleoproteln into protein and nucleic acid; a polynucleotidase which fragments the nucleic acid into nucleotids; a nucleotidase which decomposes the nucleotids into nucleoids and phosphoric acid; and, finally, a nucleosidase which attacs the nucleosids with production of sugar and purin or pyramidin bases. Now, it is evident that none of the enzyms which act on the nucleic acid and its products can enter into activity before the decomposition of the nucleoproteln by the protease present in the medium takes place. Leikewise, the nucleosidase cannot works without the nucleotidase previously decomposing the nucleotids, neither the latter can act before the entering into activity of the polynucleotidase for liberating the nucleotids. The number of enzyms which may work at a time depends upon the substances present m the protoplasm. The start and the end of enzym activities, the direction of the reactions toward the decomposition or the synthesis of chemical compounds, the duration of the reactions, all are in the dependence respectively o fthe nature of the substances, of the end products being left in, or retired from the medium, and of the amount of material present. The velocity of the reaction is conditioned by different factors as temperature, pH of the medium, and others. Genetists fall again into contradiction when they say that genes act like enzyms, controlling the reactions in the cells. They do not remember that to cintroll a reaction means to mark its beginning, to determine its direction, to regulate its velocity, and to stop it Enzyms, as we have seen, enjoy none of these properties improperly attributed to them. If, therefore, genes work like enzyms, they do not controll reactions, being, on the contrary, controlled by substances and conditions present in the protoplasm. A gene, like en enzym, cannot go into play, in the absence of the substance to which it is specific. Tne genes are considered as having two roles in the organism one preparing the characters attributed to them and other, preparing the medium for the activities of other genes. At the first glance it seems that only the former is specific. But, if we consider that each gene acts only when the appropriated medium is prepared for it, it follows that the medium is as specific to the gene as the gene to the medium. The author concludes from the analysis of the manner in which genes perform their function, that all the genes work at the same time anywhere in the organism, and that every character results from the activities of all the genes. A gene does therefore not await for a given medium because it is always in the appropriated medium. If the substratum in which it opperates changes, its activity changes correspondingly. Genes are permanently at work. It is true that they attend for an adequate medium to develop a certain actvity. But this does not mean that it is resting while the required cellular environment is being prepared. It never rests. While attending for certain conditions, it opperates in the previous enes It passes from medium to medium, from activity to activity, without stopping anywhere. Genetists are acquainted with situations in which the attended results do not appear. To solve these situations they use to make appeal to the interference of other genes (modifiers, suppressors, activators, intensifiers, dilutors, a. s. o.), nothing else doing in this manner than displacing the problem. To make genetcal systems function genetists confer to their hypothetical entities truly miraculous faculties. To affirm as they do w'th so great a simplicity, that a gene produces an anthocyanin, an enzym, a hormone, or the like, is attribute to the gene activities that onlv very complex structures like cells or glands would be capable of producing Genetists try to avoid this difficulty advancing that the gene works in collaboration with all the other genes as well as with the cytoplasm. Of course, such an affirmation merely means that what works at each time is not the gene, but the whole cell. Consequently, if it is the whole cell which is at work in every situation, it follows that the complete set of genes are permanently in activity, their activity changing in accordance with the part of the organism in which they are working. Transplantation experiments carried out between creeper and normal fowl embryos are discussed in order to show that there is ro local gene action, at least in some cases in which genetists use to recognize such an action. The author thinks that the pleiotropism concept should be applied only to the effects and not to the causes. A pleiotropic gene would be one that in a single actuation upon a more primitive structure were capable of producing by means of secondary influences a multiple effect This definition, however, does not preclude localized gene action, only displacing it. But, if genetics goes back to the egg and puts in it the starting point for all events which in course of development finish by producing the visible characters of the organism, this will signify a great progress. From the analysis of the results of the study of the phenocopies the author concludes that agents other than genes being also capaole of determining the same characters as the genes, these entities lose much of their credit as the unique makers of the organism. Insisting about some points already discussed, the author lays once more stress upon the manner in which the genes exercise their activities, emphasizing that the complete set of genes works jointly in collaboration with the other elements of the cell, and that this work changes with development in the different parts of the organism. To defend this point of view the author starts fron the premiss that a nerve cell is different from a muscle cell. Taking this for granted the author continues saying that those cells have been differentiated as systems, that is all their parts have been changed during development. The nucleus of the nerve cell is therefore different from the nucleus of the muscle cell not only in shape, but also in function. Though fundamentally formed by th same parts, these cells differ integrally from one another by the specialization. Without losing anyone of its essenial properties the protoplasm differentiates itself into distinct kinds of cells, as the living beings differentiate into species. The modified cells within the organism are comparable to the modified organisms within the species. A nervo and a muscle cell of the same organism are therefore like two species originated from a common ancestor : integrally distinct. Like the cytoplasm, the nucleus of a nerve cell differs from the one of a muscle cell in all pecularities and accordingly, nerve cell chromosomes are different from muscle cell chromosomes. We cannot understand differentiation of a part only of a cell. The differentiation must be of the whole cell as a system. When a cell in the course of development becomes a nerve cell or a muscle cell , it undoubtedly acquires nerve cell or muscle cell cytoplasm and nucleus respectively. It is not admissible that the cytoplasm has been changed r.lone, the nucleus remaining the same in both kinds of cells. It is therefore legitimate to conclude that nerve ceil ha.s nerve cell chromosomes and muscle cell, muscle cell chromosomes. Consequently, the genes, representing as they do, specific functions of the chromossomes, are different in different sorts of cells. After having discussed the development of the Amphibian egg on the light of modern researches, the author says : We have seen till now that the development of the egg is almost finished and the larva about to become a free-swimming tadepole and, notwithstanding this, the genes have not yet entered with their specific work. If the haed and tail position is determined without the concourse of the genes; if dorso-ventrality and bilaterality of the embryo are not due to specific gene actions; if the unequal division of the blastula cells, the different speed with which the cells multiply in each hemisphere, and the differential repartition of the substances present in the cytoplasm, all this do not depend on genes; if gastrulation, neurulation. division of the embryo body into morphogenetic fields, definitive determination of primordia, and histological differentiation of the organism go on without the specific cooperation of the genes, it is the case of asking to what then the genes serve ? Based on the mechanism of plant galls formation by gall insects and on the manner in which organizers and their products exercise their activities in the developing organism, the author interprets gene action in the following way : The genes alter structures which have been formed without their specific intervention. Working in one substratum whose existence does not depend o nthem, the genes would be capable of modelling in it the particularities which make it characteristic for a given individual. Thus, the tegument of an animal, as a fundamental structure of the organism, is not due to gene action, but the presence or absence of hair, scales, tubercles, spines, the colour or any other particularities of the skin, may be decided by the genes. The organizer decides whether a primordium will be eye or gill. The details of these organs, however, are left to the genetic potentiality of the tissue which received the induction. For instance, Urodele mouth organizer induces Anura presumptive epidermis to develop into mouth. But, this mouth will be farhioned in the Anura manner. Finalizing the author presents his own concept of the genes. The genes are not independent material particles charged with specific activities, but specific functions of the whole chromosome. To say that a given chromosome has n genes means that this chromonome, in different circumstances, may exercise n distinct activities. Thus, under the influence of a leg evocator the chromosome, as whole, develops its "leg" activity, while wbitm the field of influence of an eye evocator it will develop its "eye" activity. Translocations, deficiencies and inversions will transform more or less deeply a whole into another one, This new whole may continue to produce the same activities it had formerly in addition to those wich may have been induced by the grafted fragment, may lose some functions or acquire entirely new properties, that is, properties that none of them had previously The theoretical possibility of the chromosomes acquiring new genetical properties in consequence of an exchange of parts postulated by the present writer has been experimentally confirmed by Dobzhansky, who verified that, when any two Drosophila pseudoobscura II - chromosomes exchange parts, the chossover chromosomes show new "synthetic" genetical effects.
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A generalized comprehensive scheme concerning the movement of materials into living cells and tissues is presented. It is designed for use by investigators and teachers who, is assumed, have a previous knowledge of the subject as well as familiarity with previously published literature on the subject. Footnotes to figure 2 X = a constituent component material, arising from extermal sources or through metabolism, capable of migration under favorable conditions. e, i, ec, ic, mc = subscripts indicating location. oC = oxidized cytoplasmic constituents specifically concerned in unidirectional (here invardly directed), diffetial translocation of a particular material X. rC = reduced cytoplasmic constituents specifically concerned. XF = specific free energy (2) of a constituent component in in external or internal phases or in cytoplasm. D = diffusion (4). EA = exchange adsorption (4). MA= metabolic accumulation (4), CI = differentially characteristic cytoplasmic interaction (4) between oC and X, determined by the genetic constitution of the biological species. ▬▬▬>= migration, where permeability to the material involved is relatively high; and ~~~~->, where relatively low. <▬▬▬>= chemical reactions. ▬▬▬>= energy changes of X; diffusion is characteristically with the direction in which the concentration or activity of the constituent decreases, exchange adsorption may be with or against the direction of concentration or activity decrease.
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Biology of Arsenura xanthopus (Walker, 1855) (Lep., Adelocephalidae), a pest of Luehea spp. (Tiliaceae), and notes on its natural enemies. In the beginning of 1950, one of the Authors made some observations about the biology of Arsenura xanthopus (Walker), in Piracicaba, State of S. Paulo, Brazil. From 1951 to 1953, both Authors continued the observations on such an important Adelocephalidae, the caterpillars of which represent a serious pest of Luehea spp. leaves. Actually, in some occasions, the caterpillars can destroy completely the leaves of the trees. The species is efficientely controlled by two natural enemies: an egg parasite (Tetrastichus sp., Hym., Eulophidae) and a fly attacking the last instar caterpillar (Winthemia tricolor (van der Wulp), Dip., Tachinidae). Tetrastichus sp. can destroy 100% of the eggs and the fly, 70 to 100% of the caterpillars. Indeed, facts as such are very interesting because we rarely know of a case of so complete a control of a pest by an insect. A. xanthopus had not yet been mentioned in our literature. Actually neither the systematic bibliography nor the economic one has treated of this species. However, a few other species of Arsenura are already known as living on Luehea spp. According to the Authors' observations, W. tricolor was also unknown by the Brazilian entomological literature. Arsenura xanthopus (Walker, 1855) After giving the sinonimy and a few historical data concerning the species, and its geographical distribution, the Authors discuss its placing in the genus Arsenura Duncan or Rhescyntis Huebner, finishing by considering Arsenura xanthopus as a valid name. The Authors put the species in the family Adelocephalidae, as it has been made by several entomologists. The host plant The species of Tiliaceae plants belonging to the genus Luehea are called "açoita-cavalo" and are well known for the usefulness of their largely utilized wood. The genus comprises exclusively American plants, including about 25 species distributed throughout the Latin America. Luehea divaricata Mart, is the best known species and the most commonly cultivated. Biology of Arsenura xanthopus Our observations show that the species passes by 6 larval stages. Eggs and egg-postures, all the 6 instars of the caterpillars as well as the chrysalid are described. The pupal period is the longest of the cycle, taking from 146 to 256 days. Data on the eclosion and habits of the caterpillars are also presented. A redescription of the adult is also given. Our specimens agreed with BOUVIER's description, except in the dimension between the extremities of the extended wings, which is a little shorter (107 mm according to BOUVlErVs paper against from 80 to 100mm in our individuals). Winthemia tricolor (van der Wulp, 1890) Historical data, geographical distribution and host are first related. W. tricolor had as yet a single known host-; Ar^-senura armida (Cramer). This chapter also contains some observations on the biolcn gy of the fly and on its behaviour when trying to lay eggs on the caterpillars' skin. The female of W. tricolor lays from 1 to 33 eggs on the skin of the last instar caterpillar. The mam region of the body where the eggs are laid are the membranous legs. Eggs are also very numerous oh the ventral surface of the thorax and abdomen. The. preference for such regions is easily cleared up considering the position assumed by the caterpillar when fixed motionless in a branch. In such an occasion, the fly approaches, the victim, puts the ovipositor out and lays the eggs on different parts of the body, mainly on the mentioned regions, which are much more easily reached. The eggs of the fly are firmly attached to the host's skin, being almost impossible to detach them, without having them broken. The minute larvae of the fly enter the body of, the host when it transforms into chrysalid. Chrysalids recentely formed and collected in nature f requentely show a few small larvae walking on its skin and looking for an adequate place to get into the body. A few larvae die by remaining in the skin of the caterpillar which is pushed away to some distance by the active movements of the chrysalid recentely formed. From 1 to 10 larvae completely grown may emerge from the attacked chrysalid about 8 days after their penetrating into the caterpillars' body and soon begin to look for an adequate substratum where they can transform themselves into pupae. In natural conditions, the metamorphosis occurs in the soil. The flies appear within 15 days. Tetrastichus sp. This microhymenoptera is economically the most interesting parasite, being commonly able to destroy the whole pos^ ture of the moth. Indeed, some days after the beginning of the infestation of the trees, it is almost impossible to obtain postures completely free of parasites. The active wasp introduces the ovipositor into the egg of the moth, laying its egg inside, from 80 to 120 seconds after having introduced it. A single adult wasp emerges from each egg. Sarcophaga lambens Wiedemann, 1830 During the observations carried out, the Authors obtained 10 flies from a chysalid that were recognized as belonging to the species above. S. lambens is a widely distributed Sarcophagidae, having a long list of hosts. It is commonly obtained from weak or died invertebrates, having no importance as one of their natural enemies. Sinonimy, list of hosts and distribution are presented in this paper. Control of Arsenura xanthopus A test has been carefully made in the laboratory just to find out the best insecticide for controlling A. xanthopus caterpillars. Four different products were experimented (DDT, Pa-rathion, BHC and Fenatox), the best results having been obtained with DDT at 0,25%. However, the Authors believe in spite of the initial damages of the trees, that the application of an insecticide may be harmful by destroying the natural agents of control. A biological desiquilibrium may in this way take place. The introduction of the parasites studied (Tetrastichus sp. and Winthemia tricolor) seems to be the most desirable measure to fight A. xanthopus.
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Descriptive and comparative studies on tongue of nineteen Molossidae, one Mystacinidae, and four Vespertilionidae bats species were carried out. Analysis was restricted to the external morphology, covering general shape of the tongue and its papillae. Types of papillae and their distribution presented considerable intergeneric variation, considering the strictly insectivorous feeding habits of these bats. Distribution of the data of tongue morphology is analyzed and compared with the phylogenetic schemes proposed previously and comments about evolutionary relationships among taxa were done.
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A survey of simulid larval parasites was carried out in different localities of the states of Mato Grosso, Minas Gerais, São Paulo, Paraná, Santa Catarina and Rio Grande do Sul, Brazil, from February 1996 to May 1998. Prevalences for the microsporidian Polydispyrenia simulii Lutz & Splendore, 1908 were found in Morungaba and Leme, São Paulo, ranging from around 0.7 to 66.7%, depending mainly on the host simulid species. Microsporidiosis was registered in localities of São Paulo, Paraná, Santa Catarina and Rio Grande do Sul. Parasitism by Isomermis sp. (Nematoda, Mermithidae) was found in Simulium larvae from Serra do Japi, ranging from 0.8 to 45.8%, depending on the simulid species and the larval microhabitat in the stream, whether a cemented ramp in a lake outlet or the natural stream bed. Parasitism by mermithids was also found in ten localities. Mycoses caused by Coelomycidium sp. were for the first time recorded for larvae of Simulium (Chirostilbia) pertinax Kollar, 1832.
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We analyzed the diet and microhabitat use for two Hylodinae anurans (Cycloramphidae), Hylodes phyllodes Heyer & Cocroft, 1986 and Crossodactylus gaudichaudii Duméril & Bibron, 1841, living in sympatry at an Atlantic Rainforest area of Ilha Grande, in southeastern Brazil. The two species live syntopically at some rocky streams. The two species differed strongly in microhabitat use. Hylodes phyllodes occurred mainly on rocks, whereas C. gaudichaudii was observed mostly on the water. Regarding diet, coleopterans, hymenopterans (ants), and larvae were the most important prey item consumed by both species. Data suggest that microhabitat use appears to be an important parameter differentiating these frogs with respect to general resource utilization.
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Neste trabalho os autores apresentam uma revisão da morfologia das gregarinas do gênero Stenophora Labbé, 1899, baseada principalmente em S. juli (Frantzius, 1848) Labbé, 1899. Caracterizam citoquìmicamente os elementos da estrutura nuclear, ficando evidenciado que o corpúsculo nuclear referido por muitos como um cariossomo apresenta reações positivas para o RNA, sendo portanto um nucléolo. O suco nuclear apresenta reações para o DNA pouco intensas, devido as granulações de cromatina se apresentarem muito finas. Fazem referências também à estrutura do nucléolo, que varia com as técnicas empregadas e salientam a necessidade de comparação dêstes resultados com aquêles obtidos com o auxílio da microscopia eletrônica e que são tratados no segundo trabalho desta série.
Resumo:
1 - Indivíduos de Stenophora juli (Frantzius, 1848) Labbé, 1899, parasitos de um Diplopoda, Rhinochricus padbergi Schubart. 1930 foram examinados em microscópia óptica e eletrônica. 2 - Os resultados do estudo citoquímico confirmam os dados obtidos por outros autores em outras espécies de gregarinas. 3 - Quanto à estrutura fina da morfologia celular foi examinada detalhadamente a película a qual apresenta cristas longitudinais de forma e estrutura complexas. 4 - No sulcos da película, entre as cristas, foram encontrados poros na membrana, por onde é realizada a secreção de muco. 5 - Aderente à película, pròpriamente dita foi encontrada, no deutomerito, uma camada homogênea de natureza desconhecida, abaixo da qual encontra-se o mionema. 6 - O septo que separa o proto do deutomerito é constituído por espêssa camada de mionemas incluindo numerosas mitocôndrias. 7 - O endoplasma é extremamente rico em granulações de paraglicogênio, aparecendo em menor quantidade os lipídeos. Observamos também mitocôndrias, retículo endoplasmático e o complexo de Golgi.
Resumo:
Lankesterella alencari n. sp. a Sporozoa that occur in the blood and CNS of the South American frog Leptodactylus acellatus is described. Since the tissue forms of this parasite have been previously reported as belonging to the genus Toxoplasma, we attempted in fection of 2 species of amphibia (Bufo marinus an dLeptodactylus ocellatus) with a Toxoplasma strain of human origen; inoculation was by intraperitoneal injection of parasite-containing ascitic fluid from infected mice. Attempt of experimental inoculation of the parasite found in the CNS of L. ocellatus in a highly susceptible host (mice) was unsuccessful. These results suggest that Toxoplasma does not occur naturally in the amphibia; be related to Toxoplasma is excluded. The following genera of haematozoa found in brazilian amphibia have been considered briedfly: Haemobartonella, Cytamoeba, Dactylosoma, Hepatozoon and Trypanosoma.
Resumo:
Cistos de Besnoitia foram encontrados nos músculos e vísceras de quinze exemplares de Didelphis marsupialis de um total de duzentos e vinte e quatro examinados. É a primeira vez que este protozoário e isolado de animais infectados naturalmente no Brasil. A transmissão experimental foi feita para animais de laboratório pela inoculação de triturados de tecidos e cistos.
Resumo:
Macromolecule synthesis of Trypanosoma cruzi in culture was monitored using radioactive tracers. Cells of different days in culture displayed a preferential incorporation of precursors as follows: 1 day for (³H)-thymidine cells; 3 days for (³H)-uridine cells, and 4 days for (³H)-leucine cells. Autoradiographic studies showed that (³H)-thymidine was incorporated in the DNA of both kinetoplast and nucleus in this order. Shifts in the intracellular content of cAMP either by addition of dibutyryl-cAMP or by stimulation of the adenylcyclase by isoproterenol, caused an inhibition in the synthesis of DNA, RNA and proteins. Addition to the T. cruzi cultures of these agents which elevate the intracellular content ofcAMP provoked an interruption of cell proliferation as a result of the impairment of macromolecule synthesis. A discrimination was observed among the stereoisomers of isoproterenol, the L configuration showing to be most active.