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Caracterização ultra-estrutural das células luteínicas bovinas derivadas de tratamento com eCG / Ultraestructural characterization of bovine luteal cells derived from ECG treatmentNathia Nathaly Rigoglio 25 August 2011 (has links)
Biotécnicas aplicadas à reprodução animal são empregadas com o intuito de melhorar qualitativa e quantitativamente os rebanhos. A superovulação assim como a estimulação do folículo dominante utilizando-se doses suprafisiológicas de eCG (gonadotrofina coriônica eqüina) são empregadas em bovinos e bubalinos, mas nem sempre alcançam os resultados esperados. Entretanto, foram relatadas alterações morfofuncionais em corpos lúteos (CL) de animais submetidos a estes tratamentos, o que implica, necessariamente, em levantamento de hipóteses relativas ao(s) mecanismo(s) pelo(s) qual(is) as gonadotrofinas exógenas alteram as funções celulares nos folículos e corpos lúteos resultantes. Com o intuito de melhor compreensão do papel exercido pelo eCG sobre a célula luteínica bovina, 16 vacas foram sincronizadas e submetidas (grupos tratados) ou não (grupo controle) ao tratamento com eCG. O tratamento foi realizado previamente (superovulação) ou posteriormente (estimulação do folículo dominante) ao desvio folicular. No dia 6 após a ovulação, estes animais foram abatidos e os CL coletados para realização de análises histológicas e ultra-estruturais, assim como o sangue coletado para dosagem de progesterona. Para comparação dos dados obtidos entre os diferentes grupos utilizou-se o programa GraphPrism e as médias foram consideradas diferentes quando p < 0.05. Em relação à densidade de mitocôndrias e densidade numérica das mitocôndrias elipsóides não houve diferença significativa entre os grupos estudados. Quando se calculou o volume total das mitocôndrias no CL bovino, houve diferença significativa do grupo superovulado em relação aos outros grupos. Já para as mitocôndrias esferóides observou-se diferença significativa do grupo estimulado comparado aos grupos controle e superovulado. À imunofluorescência os animais do grupo superovulado apresentaram visualmente uma marcação mais fluorescente intensa para mitocôndrias quando comparados aos grupos controle e estimulado; e o grupo estimulado apresentou uma marcação mais intensa em relação ao grupo controle. Houve diferença significativa entre os três grupos em relação à quantidade das células luteínicas grandes. Quando se corrigiu o número de células luteínicas grandes pelo volume do CL, os mesmos resultados foram encontrados. Quanto às medidas do maior diâmetro das células luteínicas grandes houve uma diferença significativa quando comparado o grupo estimulado com os demais. Aspectos qualitativos da microvascularização do CL em animais controle e superovulados revelam vascularização mais abundante no grupo tratado. Estes dados apontam para modificações morfológicas da célula luteínica e do CL bovino direcionadas à maior produção hormonal após tratamento com eCG e indicam que doses diferentes aplicadas em momentos diferentes do ciclo estral levam à respostas diversas da célula luteínica e do próprio CL. / Biotechnologies applied to animal reproduction are employed in order to improve livestock quality and quantity. Superovulation and the stimulation of the dominant follicle using supraphysiological doses of eCG (equine chorionic gonadotropin) are used in cattle and buffaloes, but not always achieve the expected results. However, morphofunctional changes in corpora lutea (CL) derived from animals submitted to these treatments were reported, which necessarily implies a survey of hypotheses regarding the mechanism(s) by which exogenous gonadotrophins result in altered cellular functions in the follicles and corpora lutea. In order to better understand the role played by eCG on bovine luteal cells, 16 cows were synchronized and submitted (treated groups) or not (control group) to treatment with eCG. The treatment was performed previously (superovulation) or after (stimulation of the dominant follicle) follicular deviation. At 6 days after ovulation, animals were slaughtered and the CL collected for histological and ultrastructural analysis, as well as blood for determining plasmaprogesterone.For statistical analysis the program Graph Prism was used and mean considered significant different when p < 0.05. In relation to mitochondria number and volume density there were no differences among the studied groups. Values of mitochondria total volume in CL were different if stimulated was compared to the other groups. Imunofluoresce for mitochondria showed a more intensive signal for animals from the superovulated group, followed by animals belonging to the stimulated group. The number of large luteal cells was different among all groups. Even though this number was corrected by CL volume, the same results were found. The biggest diameter of large luteal cells was compared among the groups and stimulated group showed higher values. Qualitative aspects of CL microvascularization in control and superovulated animals reveal more abundant vascularization in treated group. These data point towards morphological modification of bovine CL and luteal cell directed to increased hormonal production after eCG treatment. Moreover, results indicate that different eCG dosis applied in different time points of estrous cycle lead to different responses from CL and luteal cells.
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Nephrin:role in the renal ultrafilter and involvement in proteinuriaRuotsalainen, V. (Vesa) 28 May 2004 (has links)
Abstract
Congenital nephrotic syndrome of the Finnish type (NPHS1, CNF) is an autosomal recessive disease that affects 1:8000 newborns in Finland. NPHS1 is characterised by heavy proteinuria already in utero and typical signs of nephrotic syndrome (NS) are present at or soon after birth. Due to the evident absence of extrarenal symptoms, NPHS1 has been considered a model disease for NS.
In this study, the NPHS1 locus on chromosome 19q13.1 was sequenced and analysed with computer programs to identify new genes in the region. Genes were further characterised and sequenced from NPHS1 patient samples, as well as from controls. Analysis of the data resulted in the identification of the affected gene with two mutations that were found to explain 94% of the Finnish NPHS1 cases. The NPHS1 gene was found to encode a novel single-pass transmembrane protein, termed nephrin, which belongs to the immunoglobulin superfamily of cell adhesion molecules.
The NPHS1 gene was cloned and recombinant nephrin fragments were produced in prokaryotic and eukaryotic expression systems. These fragments were used to raise antibodies that were utilized to characterise the spatial and temporal expression of nephrin in kidney glomeruli. Nephrin was localised by electron microscopy (EM) in ladder-like structures of the early junctional complexes of developing columnar podocytes at the capillary stage. In mature glomeruli, nephrin was localised to the slit diaphragm (SD) between adjacent glomerular podocyte foot processes.
In order to investigate the more general involvement of nephrin in proteinuric disease, its expression was studied in primary acquired NS by immunofluorescence microscopy. The level of nephrin expression was found to be significantly reduced in membranous glomerulonephritis, minimal change disease and in focal segmental glomerulosclerosis.
The known effects of nephrin mutations, together with the structure predicted from its sequence and localisation of the protein to the SD, emphasizes its indispensable role in maintaining the integrity of the glomerular filtration barrier. The glomerular basement membrane has long been considered to possess the size-selective filtration property of the filtration barrier. However, the identification of nephrin in the SD, as well as its alterations in proteinuria, has led us to reconsider SD as the final decisive size-selective filter.
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Diverzita a fylogeneze archaméb / Diversity and phylogeny of ArchamoebaeZadrobílková, Eliška January 2016 (has links)
Members of the group Archamoebae are free-living or endobiotic amoeboid flagellates and amoebae. They live in anoxic or microoxic habitats, and their mitochondria have been reduced. They were originally thought to lack mitochondria and represent one of the earliest eukaryotes. However, this hypothesis has been refuted, and now it is evident that the Archamoebae belongs to the lineage Conosa within the supergroup Amoebozoa, together with aerobic slime molds (Macromycetozoa) and variosean amoebae and flagellates. Relatively simple microtubular cytoskeleton is a characteristic feature of Archamoebae. It consists of a single basal body from which a flagellum arises, lateral root, and microtubular cone. Cytoskeleton of aflagellated genera has been completely reduced. About 350 species names of Archamoebae have been created so far. However, most descriptions were based on inadequate morphological features. The identity of numerous species is uncertain, and many of them are likely synonymous. Another problem is a small amount of available molecular data. During our project, we have substantially improved the dataset of DNA sequences of archamoebae. On the basis of molecular and morphological data, we described 13 new species. We showed that genus Rhizomastix belongs to Archamoebae and displays a new type...
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Vigour of fungicide-treated and untreated maize seed following storageGovender, Veloshinie 18 November 2008 (has links)
An assessment of the effect that conventional storage structures, used by smallscale farmers in northern Kwa-Zulu Natal and southern Mozambique, had on germination and vigour of maize seeds was conducted. The survey confirmed that the methods of storing the seed decreased the quality of the maize seeds. Storing maize in the field was good as a short-term solution as initial germination was 100%. Following storage at suboptimum conditions, germination dropped to 25.3%. Commercially treated maize seeds were compared to the test samples collected. After storage, the commercially treated seeds maintained a germination percentage above 75. Untreated maize seeds were treated with fungicides at the recommended dosages. Thereafter the seeds were subjected to germination and vigour tests according to methods outlined by the International Seed Testing Association. All treatments maintained percentage germination above 75. Apron® XL had the highest percentage germination of 83. This trend was also found following the cold test and greenhouse emergence. None of the treatments differed significantly from the control. In this study none of the treatments caused major imbibition damage as indicated by the percentage weight increase and the low leachate conductivity (1012-1271 ìScm-1g-1). The effect of accelerated ageing (AA, 2 and 4 days) and long-term storage (3 and 6 months) on germination and vigour of treated maize seeds was investigated. In the untreated control and treatments there was a gradual decrease in germination following ageing and storage of the seeds. Apron® XL failed to germinate after 3 months. The decrease in germination was mirrored by the leachate conductivity readings. Thiram was the only treatment to maintain germination after 6 months storage. The seeds were planted in two greenhouse trials to assess the performance of the treatments in vivo. The first trial evaluated the emergence and second the emergence and control of Fusarium graminearum. Results from the first trial showed that following 2 d AA, seeds treated with Thiram had the highest percentage emergence (70.7) followed by Celest® XL (68) and the untreated control (62.7). Following inoculation, a similar trend was seen for the treatments and the untreated control. In relation to the percentage seedlings emerged, the control had the highest percentage diseased seedlings. Celest® XL had the lowest percentage diseased seedlings (10, 2 and 1) but failed to germinate after 6 months storage. Thiram was the only treatment to emerge after 6 months storage. The ultrastructural changes in embryonic roots of the untreated control, Celest® XL and Apron® XL were investigated using transmission electron microscopy. These seeds were subjected to 48 hr rapid imbibition and 2 d AA. The most obvious difference between the untreated control, Apron® XL and Celest® XL was the number and position of the vacuoles. In contrast the lipid layer was still attached to the cell wall in the Apron® XL and Celest® XL treatments but in the untreated control they appeared more concentrated in the cytoplasm. This study proved that Thiram was the best treatment among the fungicides tested. However, these results need to be confirmed using a larger range of maize seed lots. / Thesis (PhD)--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted
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Antimicrobial activity and fumonisins associated with cowpea (Vigna unguiculata)Kritzinger, Quenton 22 February 2006 (has links)
A survey involving 71 farmers from rural communities in Mpumalanga, South Africa was conducted to gather information regarding the importance and utilisation of cowpea. Cowpea was rated third most important in contributing to household security, preceded by maize and vegetable production. Cowpea was mainly produced for own consumption, as a source of income and as fodder for livestock to a lesser extent. The crop was used by 8.5% of the farmers for medicinal purposes. Results indicated that 20% of the farmers encountered problems with mouldiness during storage, with insect infestation to a lesser degree. Cowpea seed samples from South Africa and Benin, West Africa were analysed for seed mycoflora and various fungal genera, particularly Aspergillus, Phoma and Lasiodiplodia were recorded. The results indicated an array of Fusarium spp. including F. equiseti, F. chlamydosporum, F. graminearum, F. proliferatum, F. sambucinum, F. scirpi, F. semitectum and F. subglutinans. The seed samples and the F. proliferatum isolates, cultured on maize patty media, were analysed for fumonisin production. Samples were extracted with methanol/water (70:30) and cleaned-up on strong anion exchange solid phase extraction cartridges. High-performance liquid chromatography with pre-column derivatisation using o-phthaldialdehyde was used for the detection and quantification of FB1, FB2 and FB3. The cowpea cultivars from South Africa had levels of FB1 ranging between 0.12 – 0.61 µg/g. All the F. proliferatum isolates produced FB1, FB2 and FB3 with total fumonisin concentration levels between 0.80 - 25.30 µg/g. The highest level of FB1 detected was 16.86 µg/g. Surface-disinfected seeds were imbibed in sterile distilled water amended with FB1 to yield final concentrations of 10, 25, 50 and 100 ppm. Percentage germination was determined in paper towels according to the International Seed Testing Association (ISTA) rules. Root and shoot length was measured after 9 days. All the toxin concentrations significantly decreased seed germination whilst root and shoot elongation was inhibited by the 50 and 100 ppm concentrations. Embryonic seed tissue treated with FB1 indicated compaction of the protoplasm and separation of the plasma membrane from the cell wall. Lipid bodies accumulated and seemed to line the cell wall. Acetone and ethanol extracts of the leaves of two cowpea cultivars exhibited significant inhibition of the growth of fungal plant pathogens at 5.0 mg/ml, with the exception of Fusarium equiseti. The growth of some fungi, in particular Alternaria alternate, was also reduced by lower concentrations of certain extracts. Acetone extracts of the Bechwana White cultivar inhibited growth of Staphylococcus aureus and Enterococcus faecalis at 2.5 mg/ml and Bacillus cereus, B. subtilis and Enterobacter cloacae at 5.0 mg/ml. Ethanol extracts of the same cultivar showed antibacterial activity against E. faecalis and E. cloacae at 5.0 mg/ml. This study represents the first report on the natural occurrence of fumonisins on cowpea seed and the potential of F. proliferatum isolates from cowpea seed to produce fumonisins. The phytotoxic effects of FB1 on cowpea seeds as well as the antimicrobial potential of cowpea leaf extracts were demonstrated for the first time. / Thesis (PhD)--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted
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Estruturas secretoras em orgão vegetativos e reprodutivos de especies de Anacardiaceae : anatomia, histoquimica e ultra-estrutura / Secretory structures in vegetative and reproductive organs of species of Anacardiaceae : anatomy, histochemistry and ultrastructureLacchia, Ana Paula Stechhahn 08 August 2018 (has links)
Orientadores: Sandra Maria Carmello-Guerreiro, Marilia de Moraes Castro, Lia Ascensão / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T00:05:44Z (GMT). No. of bitstreams: 1
Lacchia_AnaPaulaStechhahn_D.pdf: 8477823 bytes, checksum: a1685fc288b20acce389a79bd6302d17 (MD5)
Previous issue date: 2006 / Resumo: Anacardiaceae é composta por 70 gêneros com aproximadamente 600 espécies de distribuição principalmente pantropical, com poucas de regiões temperadas. A classificação infrafamiliar mais amplamente utilizada, proposta por Engler (1892), divide a família em cinco tribos: Anacardieae, Rhoeae, Semecarpeae, Spondiadeae e Dobineeae. No presente trabalho, foram estudadas uma espécie da tribo Anacardieae (Anacardium humile St.Hil), uma espécie da tribo Rhoeae (Lithraea molleoides (Vell.) Engl. e duas espécies da tribo Spondiadeae (Spondias dulcis G.Forst e Tapirira guidnensis Aubl.). As estruturas secretoras dos órgãos vegetativos e reprodutivos destas espécies foram caracterizadas anatômica e histoquimicamente e apenas os canais secretores foram caracterizados ultra-estruturalmente. Os canais têm epitélio unisseriado; os associados ao floema são resiníferos (lato sensu) e os
medulares de A. humile e S. dulcis, são mucilaginosos. A presença de canais produzindo secreções quimicamente distintas em um mesmo órgão, de uma mesma espécie, está sendo descrita pela primeira vez neste tranalho. Em A. humile, L. molleoides e T.guianensis os canais estão associados ao floema da pétala, sépala, receptáculo, pedicelo florais de todas as flores e ao floema do mesofilo
ovariano das flores pistiladas e do pistilódio das flores estaminadas de L. molleoides e, T. guianensis. Canais também são encontrados no fruto e pedúnculo de A. humile e no fruto de T. guianensis. Os canais têm epitélio unisseriado; os florais de A. humile, L. molleoides e T. guianensis são resiníferos (lato sensu), os do fruto e pedúnculo de A. humile são resiníferos (stricto sensu) e os do fruto de T.
guianensis são resiníferos (lato sensu). Em uma mesma espécie os canais secretores presentes em diferentes órgãos podem produzir substâncias distintas¿Observação: O resumo, na íntegra poderá ser visualizado no texto completo da tese digital / Abstract: Anacardiaceae is comprised of 70 genera with approximately 600 species of pantropical distribution, mainly, with few species from temperate regions. The most used infrafamilial classification, proposed by Engler (1892), divides this family in five tribes: Anacardieae, Rhoeae, Semecarpeae, Spondiadeae, and Dobineeae. In the present work, there were studied a species from
Anacardieae tribe (Anacardium humile St.Hil), a species from Rhoeae tribe (Lithraea molleoides (Vell.) Engl., and two species from Spondiadeae tribe (Spondias dulcis G.Forst and Tapirira guianensis Aubl.). The secretory structures of the vegetative and reproductive organs of these species were characterized anatomically and histochemically, and the secretory canals present in them were ultrastructurally characterized. The canals present uniseriate epithelium; the ones associated to the phloem are resiniferous
(lato sensu) and the medullar ones of A. humile and S. dulcis are mucilaginous. The presence of canals that produce chemically distinct secretions in the same organ of a species is being described for the first time. In A. humile, L. molleoides, and T. guianensis, the canals are associated to the phloem of petal, sepal, receptacles, and ovarian mesophyll; only in the pistil-like structure of the male flowers of L. molleoides and T. guianensis, there are found some canaIs. The canals are also found in the fruit and peduncle of A. humile and in the fruit of T. guianensis. The canaIs have uniseriate epithelium; the floral canaIs of A. humile, L. molleoides, and T. guianensis are resiniferous (lato sensu), the ones from fruit and peduncle of A. humile are resiniferous (stricto sensu), and the ones from the fruit of T. guianensis are resiniferous (lato sensu). In the same species, the secretory canaIs present in different organs may produce distinct substances...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Doutor em Biologia Vegetal
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Análise da porosidade nanométrica de materiais lignocelulósicos derivados de bagaço de cana-de-açúcar submetidos à compressão úmida / Analysis of nanometric porosity of lignocellulosic materials derived from bagasse sugarcane and submitted to wet pressingMarcelo Miranda de Oliveira 15 April 2014 (has links)
Neste trabalho investigamos a porosidade nanométrica de materiais lignocelulósicos derivados do bagaço de cana-de-açúcar que foram submetidos à compressão úmida. A produção dos materiais estudados a partir do bagaço de cana-de-açúcar utilizou processos de tratamento hidrotérmico seguido de processos de deslignificação organossolve (etanol-água) e soda (hidróxido de sódio). Os tratamentos hidrotérmicos utilizaram a fração fibra do bagaço de cana-de-açúcar, no estado bruto e moído, seguindo planejamento experimental fatorial de 2² com ponto central mais configuração estrela. O tratamento hidrotérmico ocorreu em temperaturas de 150-190°C com tempos de 20-60 minutos. Os processos de deslignificação utilizaram temperaturas de 160°C e 190°C para o processo soda e organossolve respectivamente, com tempos de 20, 40, 60, 80 e 100 minutos de tratamento. Os ensaios de compressão úmida foram realizados com cargas de 5, 10, 15, 20 e 25 toneladas e mostraram que materiais mais homogêneos e com menor granulometria, como o material moído e as polpas, são mais fáceis de comprimir. No entanto, os ensaios mostraram que os materiais comprimidos não são homogêneos, apresentando uma variação no teor de humidade do material comprimido (o centro da pastilha é mais seco que a periferia). O adensamento dos materiais também não é homogêneo, sendo o centro mais denso que a periferia das pastilhas. A perda de água durante a compressão foi de 74-85% para o material tratado hidrotermicamente, 66-85% para as polpas obtidas no processo soda e 81-94% para as polpas obtidas no processo organossolve. As análises de termoporometria mostraram que fração apreciável da porosidade nanométrica dos materiais deslignificados é colapsada com as menores pressões aplicadas (21 MPa). Incrementos de pressão (até carga de 107 MPa) promovem reduções comparativamente muito menores na porosidade nanométrica. / In this work we investigate the nanometric porosity of lignocellulosic materials derived from sugarcane bagasse and tested for wet pressing. The production of the studied materials from sugarcane bagasse employed hydrothermal treatments followed by organosolv (ethanol-water) and soda (sodium hydroxide) delignifications. For the hydrothermal treatments, we used bagasse fiber fractions in crude and milled states, following the factorial experimental design of 2² with central point plus star configuration. Hydrothermal treatment used temperatures of 150-190°C and times of 20-60 minutes. The delignification processes used temperatures of 160°C and 190°C for the soda and organosolv, respectively, with treatment times of 20, 40, 60, 80 and 100 minutes. Wet pressing was carried out with loads of 5, 10, 15, 20 and 25 tons and showed that materials with small and homogeneous particles such as the ground materials and the pulps are easier to compress and form a mass of material. However, the tests showed that the compressed materials are not homogeneous, presenting variations in the moisture content of the compressed materials (the center of the tablets were dryer than the periphery). Densification of the materials is also not uniform, the center being denser than the periphery. Water loss during compression was 74-85% for hydrothermally treated material, 66-85% for soda pulps and 81-94% for organosolv pulps. Thermoporometry analysis showed that appreciable fraction of the nanoscale porosity of the delignified materials collapse with the lowest applied pressures (21 MPa). Pressure increments (up to 107 MPa) promotes comparatively much lower reduction on nanoscale porosity.
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Desenvolvimento foliar em Ruschioideae (Aizoaceae), com ênfase na formação e estrutura dos feixes vasculares periféricos / Leaf development in Ruschioideae (Aizoaceae), with emphasis in the formation and structure of peripheral vascular bundlesAline Siqueira Nunes 22 August 2013 (has links)
Popularmente conhecidas como flowering stones ou ice plants, as plantas da família Aizoaceae (Caryophyllales) caracterizam-se por suas folhas suculentas morfologicamente diversas. Com centro de origem no sul da África, a maior parte das espécies pertence a subfamília Ruschioidaeae, com plantas de folhas dorsiventrais, cilíndricas e trígonas, sendo marcante a ocorrência de conação entre as bases de folhas opostas, e a presença de feixes vasculares periféricos, com xilema endoscópico. Nosso estudo mostra que a formação dos feixes vasculares periféricos é posterior ao estabelecimento da blastozona marginal, e que tecidos da face abaxial diferenciam-se no domínio adaxial da folha durante a histogênese da lâmina. Sugerimos que um mecanismo de abaxialização foliar esteja vinculado à formação da margem foliar de Aizoaceae. O xilema dos feixes vasculares periféricos é formado wide band tracheids - \"wbts\", um tipo especializado de elemento traqueal com acentuado espessamento da parede secundária. \"Wbts\" vinculam-se a órgãos suculentos e ocorrem somente em Aizoaceae, Anacampserotaceae e Cactaceae, tendo despertado interesse dos pesquisadores quanto à sua origem e função. A partir de análises comparativas de anatomia, ultraestrutura e de imunomarcação de pectina, concluímos que a definição de \"wbts\" deve ser mantida nas famílias, no entanto, destacamos a possível ocorrência de idioblastos traqueoidais na região de medular de algumas espécies. Este trabalho contribui no conhecimento da anatomia e ontogênese foliar de Aizoaceae, abrindo oportunidades de estudos sobre os mecanismos envolvidos no estabelecimento da dorsiventralidade em folhas de simetria radial. A análise comparativa de wide-band tracheids \"wbts\" em Aizoaceae, Anacampserotaceae e Cactaceae traz contribuições ao conhecimento sobre sua distribuição e características nos diferentes órgãos / Popularly known as flowering stones or ice plants, the species of Aizoaceae (Caryophyllales) are characterized by morphologically diverse succulent leaves. With center of origin in Southern Africa, most species are classified in the subfamily Ruschioidaeae, which present dorsiventral, cylindrical and three-angled leaved plants, being remarkable the occurrence of conation between the bases of opposite leaves, and the presence of peripheral vascular bundles with endoscopyc xylem. Our study shows that the formation of peripheral vascular bundles occurs after the marginal blastozone establishment, and abaxial tissues differentiate in the adaxial domain of the leaf, during blade histogenesis. We suggest that an abaxialization mechanism is involved in the formation of leaf margins in Aizoaceae. The xylem of peripheral vascular bundles is composed by wide band tracheids - wbts, a specialized type of cell that occurs only in Aizoaceae, Cactaceae Anacampserotaceae. The origin and function of this cell type has been the subject of study by some researchers. By means of comparative analysis of anatomy, ultrastructure and pectin immunolabeling, we conclude that the definition of \"wbts\" should be kept in the three families; however, we highlight the possibility of idioblasts tracheids in the some cases. This work contributes to the knowledge of leaf anatomy and ontogenesis in Aizoaceae, opening opportunities for studies on the mechanisms involved in the establishment of dorsiventrality in leaves with radial symmetry. A comparative analysis of wbts in Aizoaceae, Cactaceae Anacampserotaceae brings contributions to knowledge about their distribution and characteristics in different organs
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VISUALIZING NANO-SCALE SYNAPTIC CHANGES DURING SINGLE DENDRITIC SPINE LONG-TERM POTENTIATION BY CORRELATIVE LIGHT AND ELECTRON MICROSCOPYUnknown Date (has links)
Dendritic spines are the major sites for receiving excitatory synaptic inputs and play important roles in neuronal signal transduction, memory storage and neuronal circuit organization. Structural plasticity of dendritic spines is correlated with functional plasticity, and is critical for learning and memory. Visualization of the changes of dendritic spines at the ultrastructural level that specifically correlated with their function changes in high throughput would shed light on detailed mechanisms of synaptic plasticity.
Here we developed a correlative light and electron microscopy workflow which combines two-photon MNI-glutamate uncaging, pre-embedding immunolabeling, Automatic Tape-collecting Ultramicrotome sectioning and scanning electron microscopy imaging. This method bridges two different visualization platforms, directly linking ultrastructure and function at the level of individual synapses. With this method, we successfully relocated single dendritic spines that underwent long-term potentiation (LTP) induced by two-photon MNI-glutamate uncaging, and visualized their ultrastructures and AMPA receptors distribution at different phases of LTP in high throughput. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
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Investigação comparativa de espermátides de quatro infraordens de Heteroptera, com ênfase nos aspectos ultraestruturais /Souza, Emi Rosane Silistino de. January 2020 (has links)
Orientador: Maria Tercília Vilela de Azeredo Oliveira / Resumo: A subordem Heteroptera possui uma enorme diversidade de insetos distribuída em sete infraordens, dentre as quais utilizamos Gerromorpha, Nepomorpha, Cimicomorpha e Pentatomomorpha. As espécies que foram estudadas da primeira infraordem, representando os insetos semi-aquáticos, são Limnogonus aduncus e Mesovelia mulsanti, da segunda infraordem, representando os aquáticos, são Belostoma anurum, Martarega sp. e Buenoa unguis, da terceira infraordem Zelus sp. e Teleonemia sp. e da última infraordem, representando juntas os terrestres, são Largus sp., Stenocoris sp., Zicca pulchra e Dysdercus sp. para descrever as ultraestruturas de suas espermátides e posterior comparação. Durante o processo de espermiogênese em geral, ocorre uma série de modificações nas espermátides antes dessas serem transformadas em espermatozoide, inclusive nos insetos. Neste trabalho verificamos por meio da Microscopia Eletrônica de Transmissão, as modificações ocorridas nas espermátides das infraordens anteriormente mencionadas. Na maioria dos insetos com hábitat aquático foi identificada uma maior variação morfológica com relação aos derivados mitocondriais, apresentando-se tanto com simetria reniforme, com simetria e padrão diferente, quanto com assimetria. Com relação aos terrestres, foi identificado predominantemente um padrão morfológico reniforme com uma área de cada derivado mitocondrial menor que a do axonema. Somente a espécie B. unguis, de hábitat aquático, evidenciou um padrão atípico, assimétri... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The suborder Heteroptera has an enormous diversity of insects distributed in seven infraorders, among which Nepomorpha, Gerromorpha, Pentatomomorpha e Cimicomorpha, The species that have been studied from the first infraorder, representing semi-aquatic insects, are Limnogonus aduncus and Mesovelia mulsanti, from the second order, representing the aquatic ones, Belostoma anurum, Martarega sp. and Buenoa unguis, from the third infraorder Zelus sp. and Teleonemia sp. and the last infraorder, representing terrestrials together, are Largus sp., Stenocoris sp., Zicca pulchra and Dysdercus sp. to describe the ultrastructures of their spermatides and further comparison. During the spermiogenesis process in general, a series of changes in spermatids occur before they are transformed into sperm, including in insects In this work we verified through Transmission Electron Microscopy, the changes occurred in the spermatids of the abovementioned infraorders. In the majority of insects with aquatic habitat, a greater morphological variation was identified in relation to mitochondrial derivatives, presenting both with reniform symmetry, with different symmetry and pattern, and with asymmetry. With respect to terrestrials, a predominantly reniform morphological pattern was identified with an area of each mitochondrial derivative smaller than the axoneme. Only the species B. unguis, of aquatic habitat, showed an atypical, asymmetric pattern of mitochondrial derivatives, in relation to that com... (Complete abstract click electronic access below) / Doutor
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