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Freire De Melo Ximenes, Maria De Fátima - One of the best experts on this subject based on the ideXlab platform.
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Histomorphological Characteristics of Digestive and Reproductive Organs of Lutzomyia wellcomei Fraiha, Shaw & Lainson (Diptera, Psychodidae)
Entomologistas do Brasil, 2013Co-Authors: Pegado Silva, Vanessa Escóssia, Freitas, Maria De Lourdes, Da Silva, Naissandra Bezerra, Pinheiro, Marcos Paulo Gomes, Freire De Melo Ximenes, Maria De FátimaAbstract:Sandflies are important vectors of tegumentary and visceral leishmaniasis in different countries. This study aimed at analyzing the histomorphological characteristics of digestive and reproductive organs in Lutzomyia wellcomei (Fraiha, Shaw & Lainson) using light microscopy techniques. Thirty females from the rural area of Nísia Floresta, Rio Grande do Norte state were selected, microsectioned and analyzed with an optical microscope using conventional hematoxylin-eosin staining. Results show three well-characterized regions in the digestive tube: the Stomodeum, mesentery and proctodeum. The Stomodeum is lined internally with a basal and epithelial membrane; the mesentery has a peritrophic matrix formed above the Stomodeum lining consisting of the simple cubic epithelium overlapping the conjunctive, also common to a capsule of gonadal lining; and the proctodeum, which structurally resembles the mesentery, but with a pyloric sphincter limiting the posterior midgut. Enveloping the digestive tube is the peritoneal membrane, of mesodermal origin. Richly-detailed internal morphological characteristics of L. wellcomei have widened knowledge of this Leishmania braziliensis (Vianna)-transmitting species, an etiologic agent of American tegumentary leishmaniasis. Características Histomorfológicas de Órgãos da Digestão de Lutzomyia wellcomei Fraiha, Shaw & Lainson (Diptera, Psychodidae) Resumo. Os flebotomíneos se destacam como importantes transmissores das leishmanioses tegumentar e visceral em diferentes países. O objetivo desse estudo foi analisar características histomorfológicas de órgãos da digestão de Lutzomyia wellcomei (Fraiha, Shaw & Lainson) por meio de técnicas de microscopia. Trinta fêmeas provenientes de área rural do município de Nísia Floresta, Rio Grande do Norte foram selecionadas, microseccionadas e analisadas por microscopia ótica. Métodos de coloração histológica por hematoxilina-eosina foram empregados nas análises. Os resultados mostram o trato digestório com as três regiões bem caracterizadas, estomodeo, mesêntero e proctodeo. O estomodeo possui uma membrana basal e uma membrana epitelial que o reveste internamente; o mesêntero possui matriz peritrófica formada acima do revestimento do estomodeo constituído de epitélio cúbico simples sobreposto ao conjuntivo comum também a uma cápsula de revestimento gonadal; e o proctodeo que se assemelha estruturalmente com o mesêntero, possuindo ainda, uma região pilórica limitando o intestino médio do posterior. Envolvendo o tubo digestório, está a membrana peritonial, de origem mesodérmica. As características morfológicas internas, observadas com riqueza de detalhes em L. wellcomei ampliam o conhecimento acerca dessa espécie, transmissora de Leishmania braziliensis (Vianna), agente etiológico de leishmaniose tegumentar americana
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Histomorphological Characteristics of Digestive Organs of Lutzomyia wellcomei Fraiha, Shaw & Lainson (Diptera, Psychodidae)
2013Co-Authors: Escóssia Pegado Silva Vanessa, Bezerra Da Silva, Naissandra, Gomes Pinheiro, Marcos Paulo, Freitas, Maria De Lourdes, Freire De Melo Ximenes, Maria De FátimaAbstract:Sandflies are important vectors of tegumentary and visceral leishmaniasis in different countries. This study aimed at analyzing the histomorphological characteristics of digestive and reproductive organs in Lutzomyia wellcomei (Fraiha, Shaw & Lainson) using light microscopy techniques. Thirty females from the rural area of Nísia Floresta, Rio Grande do Norte state were selected, microsectioned and analyzed with an optical microscope using conventional hematoxylin-eosin staining. Results show three well-characterized regions in the digestive tube: the Stomodeum, mesentery and proctodeum. The Stomodeum is lined internally with a basal and epithelial membrane; the mesentery has a peritrophic matrix formed above the Stomodeum lining consisting of the simple cubic epithelium overlapping the conjunctive, also common to a capsule of gonadal lining; and the proctodeum, which structurally resembles the mesentery, but with a pyloric sphincter limiting the posterior midgut. Enveloping the digestive tube is the peritoneal membrane, of mesodermal origin. Richly-detailed internal morphological characteristics of L. wellcomei have widened knowledge of this Leishmania braziliensis (Vianna)-transmitting species, an etiologic agent of American tegumentary leishmaniasis.Os flebotomíneos se destacam como importantes transmissores das leishmanioses tegumentar e visceral em diferentes países. O objetivo desse estudo foi analisar características histomorfológicas de órgãos da digestão de Lutzomyia wellcomei (Fraiha, Shaw & Lainson) por meio de técnicas de microscopia. Trinta fêmeas provenientes de área rural do município de Nísia Floresta, Rio Grande do Norte foram selecionadas, microseccionadas e analisadas por microscopia ótica. Métodos de coloração histológica por hematoxilina-eosina foram empregados nas análises. Os resultados mostram o trato digestório com as três regiões bem caracterizadas, estomodeo, mesêntero e proctodeo. O estomodeo possui uma membrana basal e uma membrana epitelial que o reveste internamente; o mesêntero possui matriz peritrófica formada acima do revestimento do estomodeo constituído de epitélio cúbico simples sobreposto ao conjuntivo comum também a uma cápsula de revestimento gonadal; e o proctodeo que se assemelha estruturalmente com o mesêntero, possuindo ainda, uma região pilórica limitando o intestino médio do posterior. Envolvendo o tubo digestório, está a membrana peritonial, de origem mesodérmica. As características morfológicas internas, observadas com riqueza de detalhes em L. wellcomei ampliam o conhecimento acerca dessa espécie, transmissora de Leishmania braziliensis (Vianna), agente etiológico de leishmaniose tegumentar americana
William H Klein - One of the best experts on this subject based on the ideXlab platform.
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multiple signaling events specify ectoderm and pattern the oral aboral axis in the sea urchin embryo
Development, 1997Co-Authors: Athula H Wikramanayake, William H KleinAbstract:In the sea urchin embryo, the animal-vegetal axis is established during oogenesis and the oral-aboral axis is specified sometime after fertilization. The mechanisms by which either of these axes are specified and patterned during embryogenesis are poorly understood. Here, we investigated the role of cellular interactions in the specification of the ectoderm territories and polarization of the ectoderm along the oral-aboral axis. Isolated animal halves (mesomeres), which are fated to give rise to oral and aboral ectoderm, developed into polarized embryoids that expressed an oral ectoderm-specific marker uniformly. These embryoids also produced neuron-like cells and serotonergic neurons, suggesting that mesomeres are autonomously specified as oral ectoderm. Mesomere-derived embryoids did not express any aboral ectoderm-specific markers, although we previously showed that aboral ectoderm-specific genes can be induced by 25 mM lithium chloride, which also induced endoderm formation (Wikramanayake, A. H., Brandhorst, B. P. and Klein, W. H.(1995). Development 121, 1497–1505). To ascertain if endoderm formation is a prerequisite for induction of aboral ectoderm by lithium and for normal ectoderm patterning in animal halves, we modulated the lithium treatment to ensure that no endoderm formed. Remarkably, treating animal halves with 10 mM LiCl at approximately 7 hours postfertilization resulted in embryoids that displayed oral-aboral axis patterning in the absence of endoderm. Application of 25 mM LiCl to animal halves at approximately 16 hours postfertilization, which also did not induce endoderm, resulted in polarized expression of the aboral ectoderm-specific LpS1 protein, but global expression of the Ecto V antigen and no induction of the Stomodeum or ciliary band. These results suggest that at least two signals, a positive inductive signal to specify the aboral ectoderm and a negative suppressive signal to inactivate oral ectoderm-specific genes in the prospective aboral ectoderm territory, are needed for correct spatial expression of oral and aboral ectoderm-specific genes. Transmission of both these signals may be prerequisite for induction of secondary ectodermal structures such as the ciliary band and Stomodeum. Thus, differentiation of ectoderm and polarization of the oral-aboral axis in Lytechinus pictus depends on cellular interactions with vegetal blastomeres as well as interactions along the oral-aboral axis.
Maria De Fátima Freire De Melo Ximenes - One of the best experts on this subject based on the ideXlab platform.
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Histomorphological Characteristics of Digestive Organs of Lutzomyia wellcomei Fraiha, Shaw & Lainson (Diptera, Psychodidae)
Entomologistas do Brasil, 2013Co-Authors: Vanessa Escóssia Pegado Silva, Naissandra Bezerra Da Silva, Marcos Paulo Gomes Pinheiro, Maria De Lourdes Freitas, Maria De Fátima Freire De Melo XimenesAbstract:Sandflies are important vectors of tegumentary and visceral leishmaniasis in different countries. This study aimed at analyzing the histomorphological characteristics of digestive and reproductive organs in Lutzomyia wellcomei (Fraiha, Shaw & Lainson) using light microscopy techniques. Thirty females from the rural area of Nísia Floresta, Rio Grande do Norte state were selected, microsectioned and analyzed with an optical microscope using conventional hematoxylin-eosin staining. Results show three well-characterized regions in the digestive tube: the Stomodeum, mesentery and proctodeum. The Stomodeum is lined internally with a basal and epithelial membrane; the mesentery has a peritrophic matrix formed above the Stomodeum lining consisting of the simple cubic epithelium overlapping the conjunctive, also common to a capsule of gonadal lining; and the proctodeum, which structurally resembles the mesentery, but with a pyloric sphincter limiting the posterior midgut. Enveloping the digestive tube is the peritoneal membrane, of mesodermal origin. Richly-detailed internal morphological characteristics of L. wellcomei have widened knowledge of this Leishmania braziliensis (Vianna)-transmitting species, an etiologic agent of American tegumentary leishmaniasis
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Histomorphological Characteristics of Digestive Organs of Lutzomyia wellcomei Fraiha, Shaw & Lainson (Diptera, Psychodidae)
2013Co-Authors: Vanessa Da Escóssia Pegado Silva, Naissandra Bezerra Da Silva, Marcos Paulo Gomes Pinheiro, Maria De Lourdes Freitas, Maria De Fátima Freire De Melo XimenesAbstract:EnglishSandflies are important vectors of tegumentary and visceral leishmaniasis in different countries. This study aimed at analyzing the histomorphological characteristics of digestive and reproductive organs in Lutzomyia wellcomei (Fraiha, Shaw & Lainson) using light microscopy techniques. Thirty females from the rural area of Nisia Floresta, Rio Grande do Norte state were selected, microsectioned and analyzed with an optical microscope using conventional hematoxylin-eosin staining. Results show three well-characterized regions in the digestive tube: the Stomodeum, mesentery and proctodeum. The Stomodeum is lined internally with a basal and epithelial membrane; the mesentery has a peritrophic matrix formed above the Stomodeum lining consisting of the simple cubic epithelium overlapping the conjunctive, also common to a capsule of gonadal lining; and the proctodeum, which structurally resembles the mesentery, but with a pyloric sphincter limiting the posterior midgut. Enveloping the digestive tube is the peritoneal membrane, of mesodermal origin. Richly-detailed internal morphological characteristics of L. wellcomei have widened knowledge of this Leishmania braziliensis (Vianna)-transmitting species, an etiologic agent of American tegumentary leishmaniasis. portuguesOs flebotomineos se destacam como importantes transmissores das leishmanioses tegumentar e visceral em diferentes paises. O objetivo desse estudo foi analisar caracteristicas histomorfologicas de orgaos da digestao de Lutzomyia wellcomei (Fraiha, Shaw & Lainson) por meio de tecnicas de microscopia. Trinta femeas provenientes de area rural do municipio de Nisia Floresta, Rio Grande do Norte foram selecionadas, microseccionadas e analisadas por microscopia otica. Metodos de coloracao histologica por hematoxilina-eosina foram empregados nas analises. Os resultados mostram o trato digestorio com as tres regioes bem caracterizadas, estomodeo, mesentero e proctodeo. O estomodeo possui uma membrana basal e uma membrana epitelial que o reveste internamente; o mesentero possui matriz peritrofica formada acima do revestimento do estomodeo constituido de epitelio cubico simples sobreposto ao conjuntivo comum tambem a uma capsula de revestimento gonadal; e o proctodeo que se assemelha estruturalmente com o mesentero, possuindo ainda, uma regiao pilorica limitando o intestino medio do posterior. Envolvendo o tubo digestorio, esta a membrana peritonial, de origem mesodermica. As caracteristicas morfologicas internas, observadas com riqueza de detalhes em L. wellcomei ampliam o conhecimento acerca dessa especie, transmissora de Leishmania braziliensis (Vianna), agente etiologico de leishmaniose tegumentar americana.
Farge Emmanuel - One of the best experts on this subject based on the ideXlab platform.
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Tissue Deformation Modulates Twist Expression to Determine Anterior Midgut Differentiation in Drosophila Embryos
Elsevier Inc., 2008Co-Authors: Desprat Nicolas, Supatto Willy, Pouille Philippe-alexandre, Beaurepaire Emmanuel, Farge EmmanuelAbstract:SummaryMechanical deformations associated with embryonic morphogenetic movements have been suggested to actively participate in the signaling cascades regulating developmental gene expression. Here we develop an appropriate experimental approach to ascertain the existence and the physiological relevance of this phenomenon. By combining the use of magnetic tweezers with in vivo laser ablation, we locally control physiologically relevant deformations in wild-type Drosophila embryonic tissues. We demonstrate that the deformations caused by germ band extension upregulate Twist expression in the stomodeal primordium. We find that stomodeal compression triggers Src42A-dependent nuclear translocation of Armadillo/β-catenin, which is required for Twist mechanical induction in the Stomodeum. Finally, stomodeal-specific RNAi-mediated silencing of Twist during compression impairs the differentiation of midgut cells, resulting in larval lethality. These experiments show that mechanically induced Twist upregulation in stomodeal cells is necessary for subsequent midgut differentiation
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Tissue deformation modulates Twist expression to determine anterior midgut differentiation in Drosophila embryos
'Elsevier BV', 2008Co-Authors: Desprat Nicolas, Supatto Willy, Pouille Philippe-alexandre, Beaurepaire Emmanuel, Farge EmmanuelAbstract:International audienceMechanical deformations associated with embryonic morphogenetic movements have been suggested to actively participate in the signaling cascades regulating developmental gene expression. Here we develop an appropriate experimental approach to ascertain the existence and the physiological relevance of this phenomenon. By combining the use of magnetic tweezers with in vivo laser ablation, we locally control physiologically relevant deformations in wild-type Drosophila embryonic tissues. We demonstrate that the deformations caused by germ band extension upregulate Twist expression in the stomodeal primordium. We find that stomodeal compression triggers Src42A-dependent nuclear translocation of Armadillo/β-catenin, which is required for Twist mechanical induction in the Stomodeum. Finally, stomodeal-specific RNAi-mediated silencing of Twist during compression impairs the differentiation of midgut cells, resulting in larval lethality. These experiments show that mechanically induced Twist upregulation in stomodeal cells is necessary for subsequent midgut differentiation. DEVBI
M. Kiefer - One of the best experts on this subject based on the ideXlab platform.
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Rathke-Zyste, Kraniopharyngeom und Kolloidzyste
Der Radiologe, 2018Co-Authors: R. Eymann, M. KieferAbstract:Clinical issue Headache is the most common symptom of colloid cysts, Rathke cysts, and craniopharyngioma due to their location in the midline, being extra-axial and typically presenting in the parasellar region. Therapeutic problems Although these tumors are generally considered benign, each has its typical characteristics defined by its location and histology. These individual characteristics define whether surgery is necessary at all and if so, the preferred surgical approach and resection’s totality. The histopathological findings primarily indicate that embryonic malformations—at the first glance, ectodermal in nature—cause these tumors. Achievement Due to the fact that these disturbances occur at the boundary between ectodermal Stomodeum and endodermal cephalogaster, however, does leave some doubts. Klinische Problematik Kopfschmerzen sind auf Grund der Lokalisation der Tumoren das häufigste gemeinsam auftretende Symptom bei Kolloidzyste, Kraniopharyngeom und Rathke-Zyste. Sie liegen mittellinig, extraaxial und finden sich typischerweise parasellär. Therapeutische Problematik Auch wenn diese Tumoren benigne sind, weist jeder einzelne – abhängig von Lokalisation und Histologie – individuelle Merkmale auf, die gewürdigt werden müssen. Diese Merkmale entscheiden, ob überhaupt eine operative Intervention erforderlich ist und falls ja, welcher operative Zugangsweg und welche Radikalität bei der Resektion zu präferieren sind. Auf Grund ihres histopathologischen Erscheinungsbildes wird mehrheitlich angenommen, dass es sich um Fehlbildungen des Ektoderms handelt. Bewertung Der Entstehungsort lässt sich jedoch auf die Grenzschicht zwischen ektodermalem Stomodeum und endodermalem Cephalogaster eingrenzen, so dass der exktodermale Ursprung noch keineswegs als gesichert gilt.
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Rathke-Zyste, Kraniopharyngeom und Kolloidzyste
Der Radiologe, 2018Co-Authors: R. Eymann, M. KieferAbstract:Kopfschmerzen sind auf Grund der Lokalisation der Tumoren das haufigste gemeinsam auftretende Symptom bei Kolloidzyste, Kraniopharyngeom und Rathke-Zyste. Sie liegen mittellinig, extraaxial und finden sich typischerweise parasellar. Auch wenn diese Tumoren benigne sind, weist jeder einzelne – abhangig von Lokalisation und Histologie – individuelle Merkmale auf, die gewurdigt werden mussen. Diese Merkmale entscheiden, ob uberhaupt eine operative Intervention erforderlich ist und falls ja, welcher operative Zugangsweg und welche Radikalitat bei der Resektion zu praferieren sind. Auf Grund ihres histopathologischen Erscheinungsbildes wird mehrheitlich angenommen, dass es sich um Fehlbildungen des Ektoderms handelt. Der Entstehungsort lasst sich jedoch auf die Grenzschicht zwischen ektodermalem Stomodeum und endodermalem Cephalogaster eingrenzen, so dass der exktodermale Ursprung noch keineswegs als gesichert gilt.
