153 resultados para APICAL PORTER


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The study of materials belonging to several brazilian collections led us discover 2 new species of the genus Colobogaster which are here described. C. seabrai sp. n. seems to be related to C. puncticollis Waterhouse, 1882, from which it can be distinguished by: a) apical alitral tooth placed suturally, b) pronotum with 3 pairs of depressions, the 1st. pair transversal and conigous to the 2nd one, c) elitral suture brilliantgreen coloured but not the marginal edge, d) front without a horse-shoe shaped structure, e) pronotum with the discal region concolor. The structures of pronotum, the elitral and pronotal colour paterns and the genial morphology separate this one from other species of the genus. C. paraensis sp. n. is closely related to C. cupricollis Kerremans, 1897, but it is distinguished by the absence of depressions on the pronotum, by the elitral tooth placed suturally, by the abscence of humeral rip and by the general colour. Eleven other species were studied and their apical segment of the abdomen and scutellum were illustrated. It was also established the synonymy of C. ecuadoricus Obengerger, 1926.

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No presente trabalho, descreve-se a estrutura microanatômica e citológica, bem como a função das glândulas laterais de um Diplópode, Rhinocricus padbergii. Chegamos aos seguintes resultados principais: 1 — Do ponto de vista anatômico o, o aparelho glandular representa uma invaginação complicada do integumento. O epitélio glandular é uma formação homóloga a hipoderme, fato provado pela presença de um revestimento cuticular e de pigmentos nas células de todo o aparelho. O sistema compõe-se de uma vesícula glandular, de um canal condutor e de um dispositivo de fechamento. 2 — Os detalhes da construção do aparelho glandular inteiro apresentamos na figura 1. Todo o complexo possui apenas um forte músculo para o movimento do aparelho de fechamento; seu antagonista é uma região elástica do próprio aparelho de fechamento que funciona à maneira de mola em virtude de numerosas dobras grudadas. 3 — A hipoderme glandular possui uma membrana basal muito fina, sendo porem reforçada, secundàriamente, por uma membrana celular mais forte. 4 — A expulsão de secreção através da abertura externa ("poro glandular") dá-se por meio de aumento da pressão no interior da cavidade geral do corpo (contrações generalizadas da musculatura inteira do corpo) e pela pressão da borda posterior do segmento anterior, exercida sobre a vesícula glandular devido a contração dos troncos da musculatura longitudinal. 5 — A respeito da função das células glandulares diferenciamos quatro estágios: a) Fase I: Na zona media da célula formam-se concentrações de secreção difusas. Os mitocôndrios localizam-se, quase exclusivamente, sobre a face basal da célula. b) Fase II: As concentrações de secreção difusas tornam-se mais densas; as esferas de secreção aumentam, gradativamente, de diâmetro e localizam-se em vacúolos, em forma de fendas, no protoplasma. Os mitocôndrios aumentam de número, distribuindo-se sobre todo o interior da célula. c) Fase III: Os vacúolos pequenos confluem em alguns grandes, , preenchendo-se com esferas de secreção, maiores e menores. Os mitocôndrios deslocam-se em direção à zona apical da célula, encontram-se porém, ainda, também em número elevado no protoplasma. d) Fase IV: Os vacúolos juntam-se, formando um só vacúolo grande que ocupa mais do que a metade do volume da célula e que é preenchida por esferas de secreção. Os mitocôndrios encontram-se agora quase exclusivamente na face apical da célula. 6 - Durante a formação das esferas de secreção ocorre no seu interior um acondensação secondária, que se inicia no centro de cada esfera, e que pode ser comparada com o mesmo fato observado nas esferas de secreção das células lipócrinas das glândulas salivares de Aedes scapularis. 7 - A secreção não é de natureza lipóide. 8 - A expulsão da secreção da célula é processo micro-apócrino. 9 - As esferas de secreção no interior da célula e a secreção contida na vesícula glandular têm uma composição química diferente. Baseando-se na migração dos mitocôndrios (veja os itens 5 a-d dêste resumo) conclui-se que, antes ou durante sua passagem através da face apical da célula, a secreção sofre uma modificação química por ação enzimática.

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Foi realizado um estudo histológico da região hipotalâmica anterior humana empregando-se a colocação pela hematoxilina crômica e a impregnação pelo carbonato de prata a fim de comparar os resultados obtidos com os dois métodos. Verificou-se que a impregnação argêntica fornecia imagens equivalentes ás obtidas com a hematoxilina crômica. Todavia, não pode ser empregada isoladamente, devendo-se sempre fazer o controle com a hematoxilina crômica. Em uma segunda parte do trabalho discute-se o fenômeno da degeneração das porções terminais e subterminais das fibras nervosas do feixe supra-óptico-hipofisário, coincidindo com a formação dos chamados "corpos de Herring". Conceitua-se estes neurônios que formam os núcleos supra-ópticos e paraventricular como um tipo de célula glandular, não obstante sua natureza neuronal, cuja eliminação do produto de elaboração coincide com a desagregação do pólo apical da célula.

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A description of the species Lymnaea diaphana King, 1830 is presented, on the basis of material collected at its type-locality, San Gregorio, on the north coast of the Strait of Magellan, in the Chilean province of Magallanes. It may be identified by the following characters taken together: adult shell over 10 mm in length, whorls inflated, regularly convex, separated by a well-marked suture, aperture ovate occupying about half the shell length; renal organ forming an approximately right angle with the ureter; pouch of the oviduct well noticeable high on the right ventral surface and on the right side of the nidamental gland; uterus bent to the right into an approximately right angle; body of the spermatheca projected into the pulmonary cavity and adhered to the pericardium and to the roof of the pulmonary cavity; spermiduct highly sinuous, folding dorsalward between the left half of the oviduct and the left shoulder of the nidamental gland, and then winding on ventralward to reach the prostate on the middle line; prostate voluminous, convex on the left, pushed in on the right, with a deep dorsal furrow corresponding to a fold which projects into the prostatic lumen and is more developed at the fore half of the organ; apical end of the penial sheath with about six minute protuberances corresponding to inner chambers; prepuce from about as long about twice as long as the penial sheath, with some variation beyond those limits; lateral teeth of the radula basically tricuspid, with a usually simple ectocone which may show a bifid or trifid point. A diagnosis between lymnaea diaphana and three other lymnaeids which also occur in South America and were previously studied by the author - L. columella, L. viatrix and L. rupestris - is presented.

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This paper deals with the morpholgy of Pomacea lineata (Spix, 1827) collected at its type locality. The shell is globose, moderately heavy, horn-colored with brown spiral bands; apex subelevated; 4 - 5 rounded whorls increasing in diameter rather rapidly, separated by deep suture. Aperture large and ovoid; outer lip sharp; umbilicus narrow and deep; operculum concentric, corneous. Ratios: shell width/shell length = 0.74 - 0.83 (mean 0.78); spire length/shell length = 0.10 - 0.18 (mean 0.13); aperture length/shell length = 0.70 - 0.77 (mean 0.73). The animal is longisiphonate. Renal organ brownish with marked invagination at its right edge. Ureter elongated with its long axis transverse to the main axis of the kidney. The radula is taenioglossate (2.1.1.1.2) and has on average 35 transverse rows of teeth. The form and arrangement of the radula teeth are nearly the same as in other Ampullariidae. The testis is cream-colored and lies in the first three whorls of the spire. Spermiduct uniformly narrow, running to the base of the spire. Seminal vesicle whitish, slightly pressed dorsoventrally. Prostate cylindric and thick, similar in color to the testis. Penis whiplike, with a closed circular spermiduct. Penis pouch ovoid completely envelping the penis. Penis sheath elongated, broad prosimally, tapering distally. Its inner surface shows a longitudinal channel along its proximal half and two glands, one on the middle and the other apical. Ovary composed of branched whitish tubules situated on the surface of the digestive gland. Oviduct slender running along the columellar axis toward the base of the spire. Seminal receptalble tubiform, thick-walled and rounded proximally. Albumen gland large, pink, enclosing the receptacle and the spiral capsule gland. Vestigial male copulatory apparatus (penis and its sheath) present in all females examined.

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A description of Pomacea sordida (Swainson, 1823) collected in Caxias and Nova Iguaçu, state of Rio de Janeiro, is presented. The shell is globose, heavy, whith greenish or horn-colored periostracum and dark spinal bands; apex subelevated, 4-5 moderately shoudered whorls, increasing rather rapidly and separated by deep suture. Aperture large, moderately round, yellowish or violaceous; lip thick and sometimes dark brown; umbilicus large and deep; operculum corneous and heavy, entirely closing the aperture. Ratios: shell width/shell length = 0.81-0.91 (mean 0.86); aperture length/shell length = 0.66-0.75 (mean 0.70). Testis, spermiduct and penis pouch as in Pomacea lineata (Spix, 1827). Seminal vesicle whitish and bean-shaped. Prostate cylindric and narrow, cream in coloar as the testis. Penis whiplike whith a closed circular spermiduct. Penial sheath elongated and tapered, with its distal tip turned to the right; outer basal gland situated on the left; inner median gland rounded; apical gland elongated and wrinkled. Ovary composed of branched whitish tubules lying superficially on the digestive gland; oviduct and seminal receptacle as in P. lineata; albumen gland yellowish - orange. Vestigial male copulatory apparatus (penis and its sheath) present in all females examined.

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The Brindley's glands of Panstrongylus megistus were studied under the antomic, histologic and ultrastructural point of view. These glands located in the insect's methatorax are paired and have an opening near the third parir of the feet. Beside this aperture, ther are evaporation areas. Shape, sixe and aspect of the gland vary according to the feeding status. The glands are composed by a tubular part corresponding to the duct and a sack-like portion corrsponding to the secretory part. By electron microscopy we observed that the basal part of the epithelium has many interdigitations associated with mitochondria. On the apical surface where epicuticular foldings are located an electonlucent space is often seen. The glands are composed of the following elements: 1) superficial epithelial cells, located just below the apical surface foldings; 2) secretory cells; which are long and have an intracellular canalicule which changes according to the functional state of the cell; 3) a collecting duct to the secretory cells and covered with an epicuticle, reaching up to the gland's lumen; and 4) cells around the duct.

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The ultrastructure and distribution of gonial and somatic cells in the ovary of Dermatobia hominis was studied during the 3rd larval instar. In larvae weighing between 400 and 500 mg, the ovary is partially divided into basal and apical regions by oblong somatic cells that penetrate from the periphery; these cells show ovoid nucleus and cytoplasm full of microtubules. In both regions, gonial cells with regular outlines, large nucleus and low electron-density cytoplasm are scattered among the interstitial somatic cells. These later cells have small nucleus and electrodense cytoplasm. Clear somatic cells with small nucleus and cytoplasm of very low electron-density are restrict to the apical region of the gonad. Degenerating interstitial somatic cells are seen in the basal portion close to the ovary peduncle. During all this larval period the morphological features of the ovary remain almost the same. At the end of the period there is a gradual deposition of glycogen in the cytoplasm of the somatic cells, increase in the number and density of their mitochondria plus nuclear modification as membrane wrinkling and chromatin condensation in masses.

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Ovaries up to the 8th day pupae of Dermatobia hominis were studied by transmission electron microscopy. Ovarioles were recognized in ovaries of 4-day old pre-pupae, surrounded by a thin tunica propria of acellular fibrilar material similar in structure to the internal portion of the external tunica of the ovary. There is continuity of the tunica propria and the ovarian tunica, indicating that the former structure originates from the tunica externa. In 5 to 7-day pupae the interstitial somatic cells from the apical region of the ovary, close to the ovarioles, show delicate filamentous material inside of their rough endoplasmic reticulum cisternae; similar material is seem among these cells. Our observations suggest that interstitial somatic cells do not originate the tunica propria but contribute to its final composition.

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We studied the ultrastructural aspects of pre-pupae and pupae ovaries of Dermatobia hominis. Physiological degeneration of gonial cells was observed: (a) after the ovarioles differentiation, in the oogonia residing in the apical region of the ovary; (b) at the beginning of vitellogenesis, in the cystoblasts close to the terminal filament. The significance of gonial cell degeneration was correlated with the physiological changes wich occur in the ovary during development.

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A new species of Gundlachia, Gundlachia dutrae is described from northwest Brazil. It is distinguishable from other congenerie species by characteristics of the shell, radula and internal organs. Shell relatively high. Aperture near-circular; periostracum dark brown without periostracal hairs. Apex slightly inclined to the right, projected but not hooked, with an apical depression surrounted by a sculpture of well-marked irregular punctations. Shell surface with prominent radial sculpture. No septate specimens were observed. Ratios (n= 59): shell width/shell lenght = 0,66- 0,79 (mean 0,73); shell height/shell length = 0,32- 0,45 ( mean 0,37); shell height/shell width = 0,43- 0,63 (mean 0,51). Body of normal ancylid type; mantle pigmentation dark brown or black, concentrated along the mantle collar. The dorsal surface of the right anterior muscle is elongated and medially constricted. The left anterior and the posterior muscles are almost elliptical. Adhesive area is V-shaped. Pseudobranch unpigmented bearing a very small and thin dorsal lobe. Ovotestis with more than 25 unbranched diverticula. Ovispermiduct with seminal vesicle rather developed. Elongated nidamental gland continous with the glandular wall of the uterus. Nidamental gland appendix ending into a bulbous swelling Spermathecal body almost rounded. Well-developed prostate with five long diverticula. Ejaculatory complex with long glandular flagellum, without a penis or true ultra-penis. "Penis sheath" developed. "Ultra-penis" projected as a tube inside the lumem of prepuce, with a slit between "ultra-penis" and "penis sheath". Rachidian tooth tetracuspid, with two median cusps assymmetrical and aculeated. Lateral teeth tricuspid, with a reduced endocon and a prominent mesocon. A well marked gap occurs between meso and ectocon. Marginal teeth similar to lateral ones. Jaw T-shaped, with about 28 dorsal plates.

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The authors revalidate the genus Mepraia, described in 1940 by Mazza, Gajardo & Jörg. The genus is monotypic and represented by the species M. spinolai (Porter, 1934). Based on the characteres described below the authors considered the separation of the genus Triatoma Laporte, 1832 and the return of the genus Mepraia. Strongly alar polymorphism, the abdomen of female with connexivum like in genus Dipetalogaster Usinger 1939, seven testicular follicles, like in Triatoma, however with a different relation of lenghts; external male genitalia showing a big and foliar process of the conjunctiva, vesica with an arch-shape, struts and endosoma process absent.

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The apical membrane antigen (AMA-1) family of malaria merozoite proteins is characterised by a high degree of inter-species conservation. Evidence that the protein (PK66/AMA-1) from the simian parasite Plasmodium knowlesi was protective in rhesus monkeys suggested that the 83kDa P. falciparum equivalent (PF83/AMA-1) should be investigated for protective effects in humans. Here we briefly review pertinent comparative data, and describe the use of an eukaryotic full length recombinant PF83/AMA-1 molecule to develop a sensitive ELISA for the determination of serological responses in endemic populations. The assay has revealed surprisingly high levels of humoral response to this quantitatively minor antigen. We also show that PK66/AMA-1 inhibitory mAb's are active against merozoites subsequent to release from schizont-infected red cells, further implicating AMA-1 molecules in red cell invasion.

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Triatoma jurbergi n. sp. is described based on nine specimens of both sexes deposited in the Rodolfo Carcavallo Collection in the Oswaldo Cruz Institute Entomological Collection. The new species can be separated from the closely related Triatoma guazu Lent & Wygodzinsky, 1979 by several characters. The most important are longer anteocular region; thin and pointed juga; the shape of the eyes without concavity in the posterior edge; much longer second rostral segment, passing the posterior edge of eye; the absence of a ventral longitudinal depression on the abdomen; the general color redish, brown and orange and the male genitalia, mainly in the vesica lightly chitinized and smaller, the phallosome with apical projection and the pointed apex of the endosome process.

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The morphology of the scolices and metascolices of 29 proteocephalid species, parasites of freshwater fishes from Brazil was compared by using scanning electron microscope, light and laser microscopy. The following species were evaluated: Proteocephalus vazzolerae, P. piramutab, Robertiella paranaensis, Travassiella avitellina, Monticellia loyolai, M. spinulifera, M. belavistensis, Houssayela sudobim, Zygobothrium megacephalum, Gibsoniela mandube, Cangatiella arandasi, Nomimoscolex sudobim, N. lopesi, N. admonticellia, N. piraeeba, N. pirarara, Harriscolex kaparari, Crepidobothrium eirasi, Spatulifer rugosa, Megathylacus brooksi, Choanoscolex abscisus, Amphoteromorphus peniculus, A. piraeeba, Paramonticellia itaipuensis, Peltidocotyle rugosa, Othinoscolex lenha, Rudolphiella rugata, R. piranabu, Jauella glandicephalus. Some features as overall shape of scolex, suckers, apical sucker, frontal glands and several kinds of metascolex were analyzed. The taxonomic importance of scolex and metascolex is discussed.