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Fundação de Amparo a Pesquisa do Estado de Minas Gerais Several functions have been attributed to the addition of glycidyl radicals in nuclear proteins. It is believed that the structural and functional changes through which they pass along the neurons of aging are associated with different patterns of protein glycosylation in the nucleus of these cells. Previous data refer that the glycosylation of nuclear proteins, mainly histones, plays an important role in epigenetic control of nuclear functions. In this context, the changes in chromatin structure epigenetic changes associates with type O-glycosylation depend, for example, the chromatin remodeling complex recruitment necessary for regulating gene transcription, with this type of control over the aging-related rise neurodegenerative diseases such as Alzheimer s disease and others. Thus, to understand the association between changes in chromatin structure due to O-glycosylation of histones and aging is critical to the development of treatments that can improve the quality of life of the population. For this purpose, it propose to study the in situ distribution of two types of sugar residues attached to proteins, as well as histones are glycosylated and if there differential glycosylation of the proteins along with aging. To this end, isolated neuronal nuclei were underwent cytochemical analysis, and biochemical assays to identify and quantify reactive glycidiy markers to ConA and WGA lectins. Results indicate that glycoproteins containing glucose / mannose and Nacetylglucosamine have differences in their pattern of nuclear distribuition, which depend on the animal age, indicating different functions depending on the composition glicidic of these glycoproteins. Our data show that all canonical (H2A, H2B, H3 e H4) in neurons are glycosylated, with different patterns are observed for each different ages. It is believed that these changes are related to structural changes in chromatin observed during the aging period, which may have a fundamental role in altered patterns of gene expression observed with increasing age. Diversas funções têm sido atribuídas à adição de radicais glicídicos em proteínas nucleares. Acredita-se que as mudanças estruturais e funcionais pelas quais passam os neurônios ao longo do envelhecimento estejam associadas com diferentes padrões de glicosilação protéica no núcleo dessas células. Estudos anteriores remetem que a glicosilação de proteínas nucleares, principalmente histonas, tem um importante papel epigenético no controle das funções nucleares. Nesse contexto, as alterações na estrutura da cromatina associadas com modificações epigenéticas tipo O-glicosilação dependem, por exemplo, do recrutamento de complexos de remodelamento da cromatina necessários à regulação da transcrição gênica, estando esse tipo de controle, ao longo do envelhecimento relacionado ao surgimento de doenças neurodegenerativas, como o mal de Alzheimer e outras. Dessa forma, entender a associação entre as mudanças da estrutura cromatínica devido à O-glicosilação de histonas e o envelhecimento é fundamental para o desenvolvimento de tratamentos que possam melhorar a qualidade de vida da população. Nesse sentido, este trabalho objetivou estudar a distribuição in situ de dois tipos de resíduos de açúcar ligados a proteínas, bem como se as histonas são glicosiladas e se há glicosilação diferencial dessas proteínas ao longo do envelhecimento em núcleos de neurônios corticais de camundongos. Para tanto, núcleos isolados de neurônios foram submetidos à análise citoquímica e ensaios bioquímicos para identificação e quantificação de marcadores glicídicos reativos às lectinas ConA e WGA. Os resultados demonstram que glicoproteínas contendo glicose/manose ou N-acetilglicosamina possuem diferenças no seu padrão de distribuição nuclear, que independem da idade do animal, evidenciando funções diferenciadas dependendo da composição glicídica dessas glicoproteínas. Adicionalmente, os dados indicam que todas as histonas canônicas (H2A, H2B, H3 e H4) são glicosiladas em neurônios, sendo que padrões diferenciados de marcação foram observados em cada uma delas para as diferentes idades. Acredita-se que tais alterações estejam relacionadas com as mudanças estruturais observadas na cromatina ao longo do envelhecimento, as quais podem ter um papel fundamental nos padrões alterados de expressão gênica observados com o avanço da idade. Mestre em Biologia Celular e Estrutural Aplicadas

The genus Rhizoctonia DC (1805) has long been studied as an important soilborne pathogen that causes a wide variety of symptoms because it is a non-specialized pathogen3. Rhizoctonia sensu lato is characterized by the lack of conidiogenous cells and this taxon is composed of two groups based on the number of nuclei per cell: the multinucleate group that belongs to Rhizoctonia s. str. and the binucleate group that belongs to Ceratorhiza5. Currently, other authors consider the group a Ceratobasidium–Rhizoctonia complex7 and divide it into two groups: BNR (binucleate Rhizoctonia-like) and MNR (multinucleate Rhizoctonia-like)9. Many methods are used to observe the number of nuclei in fungal cells, e.g. safranine O, aniline blue, HCl-Giemsa. Some of these methods apply a staining solution involving laborious, time-consuming procedures that require no equipment (Fig. 1). Other methods use fluorophores, which are rapid and precise Fil: Barrera, Viviana Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola; Argentina Fil: Gutierrez, Susana. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Cátedra de Fitopatología; Argentina Fil: Cúndom, María Águeda. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Cátedra de Fitopatología; Argentina Fil: Gasoni, Amelia Laura. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola; Argentina

Made available in DSpace on 2015-04-23T20:28:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-12-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Os triatomíneos são insetos hematófagos que apresentam interesse médico nas América do Sul e Central por serem hospedeiros invertebrados dos protozoários hemoflagelados Trypanosoma cruzi (agente etiológico da doença de Chagas) e Trypanosoma rangeli (Tejera, 1920). Os triatomíneos do gênero Rhodnius possuem glândula salivar formada por duas unidades próximas e independentes: a principal e a acessória. Esta glândula secreta uma saliva que contém substâncias que facilitam e permitem a hematofagia. Entretanto, apesar da sua importância, poucos estudos realizaram sua análise citoquímica. No propósito de ampliar esse entendimento, neste trabalho foram investigadas as estruturas nucleares (cromatina e corpúsculos nucleolares) das células da glândula salivar de Rhodnius neglectus (Lent, 1954) e Rhodnius prolixus (Stål, 1859). As glândulas foram removidas de insetos adultos, fixadas e submetidas a diferentes métodos citoquímicos: Orceína Lacto-Acética, Impregnação por Íons de Prata, Reação de Feulgen, Azul de Toluidina, Variante da Concentração Eletrolítica Crítica e Bandamento C. Os resultados evidenciaram predomínio de células binucleadas, com núcleos volumosos e poliplóides, cromatina descondensada e uma grande área nucleolar. Além disso, foi observada metacromasia citoplasmática e uma clara associação entre os corpúsculos nucleolares e heterocromáticos. Tais características foram associadas às atividades de intensa síntese proteica para a produção de saliva. Além disso, os corpúsculos heterocromáticos observados no Bandamento C permitiram a diferenciação dos sexos e das espécies. Triatomines are hematophagous bugs of medical interest in South and Central America, where they may act as invertebrate hosts of the hemoflagellate protozoa Trypanosoma cruzi (the causative of Chagas’ disease) and Trypanosoma rangeli (Tejera, 1920). Triatomines of Rhodnius genus have salivary gland formed by two close and independent units: the principal and the accessory. This gland secretes saliva that abounds in substances that facilitate and permit feeding. Despite this importance, there are few reports on its cytochemistry. In purpose of amplifying this understanding, in this work it was investigated the nuclear structures (chromatin and nucleolar corpuscles) of salivary gland cells of Rhodnius neglectus (Lent, 1954) and Rhodnius prolixus (Stål, 1859). The salivary glands were removed from adult insects, fixed and submitted to different cytochemical methods: lacto-acetic orcein, silver ion impregnation, Feulgen reaction, Toluidine Blue, Variant method of critical electrolyte concentration and C-banding. The results evidenced predominance of binucleated cells, with bulky and polyploid nucleus, decondensed chromatin and a large nucleolar area. In addition, cytoplasmic metachromasy and a clear association between nucleolar and heterochromatic corpuscles were observed. Such characteristics were associated with intense synthesis activity to produce saliva. Besides, the heterochromatic corpuscles observed with C Banding permitted the differentiation of sexes and species. UNESP IBILCE Departamento de Biologia UNESP IBILCE Departamento de Biologia

O valor C de DNA é um caráter de significado biológico fundamental e o conhecimento da quantidade de DNA nuclear de um grupo de organismos pode ser útil em vários campos da ciência. Do ponto de vista prático, a determinação da quantidade de DNA nuclear, que é mais comumente realizada por microdensitometria de Feulgen e citometria de fluxo, pode substituir a contagem de cromossomos, especialmente quando se trabalha com um número muito grande de indivíduos. A microdensitometria por Feulgen baseia-se na ligação específica do DNA a esse corante, havendo uma proporcionalidade entre a quantidade de DNA existente e a quantidade de corante que o núcleo incorporou. A citometria de fluxo envolve a análise das propriedades óticas de partículas em fluxo. Em plantas, basicamente consiste no isolamento dos núcleos, coloração destes com um fluorocromo e leitura da fluorescência emitida As grandes vantagens desta técnica, em relação à microdensitometria de Feulgen, são a relativa facilidade e a rapidez da preparação das amostras, o grande número de núcleos que podem ser analisados, a necessidade de pequenas quantidades de tecido e a possibilidade de detecção de pequenas diferenças na quantidade de DNA. Relatos de resultados conflitantes entre determinações de diferentes autores mostram a necessidade de uma criteriosa padronização das técnicas, para que problemas metodológicos não venham a ser interpretados como eventuais diferenças reais na quantidade de DNA. The DNA C value is an important biological characteristic and the knowledge of DNA content may be applied to several branches of science. Nuclear DNA content determinations, normally performed by Feulgen microdensitometry and flow cytometry, may replace chromosome counts especially when a high number of individuals are being analysed. Feulgen microdensitometry is based on the affinity of this dye and the DNA: the amount of DNA is proportional to the amount of dye taken by the nucleus. Flow cytometry is based on the optical properties of particles on a flow. In plants the technique basically consists in the isolation of nuclei, staining with a fluorochrome and measurement of the emitted fluorescence. The advantages of this technique, when compared to Feulgen densitometry, are the relative easiness and speed of sample preparation, the possibility to analyse a high number of nuclei, the need of small tissue amounts and the detection of small differences in DNA contents. Conflicting results from different authors show the need of a rigid technical standardization so that methodological errors are not misinterpreted with eventual real differences in DNA contents.

La propuesta de aula: el ciclo celular y su papel en el desarrollo, crecimiento, restitución y reparación de tejidos, es diseñada para estudiantes de ciclo tres, tiene como población de estudio, los estudiantes de grado séptimo de la institución educativa Jesús María Aguirre Charry, La propuesta de aula se inicia con un diagnóstico de los conceptos previos esenciales para la comprensión del ciclo celular; a partir del cual se definen los problemas cognitivos presente en los estudiantes. Durante la propuesta se propone una fase refuerzo, la cual se espera colabore en la superación de los conflictos cognitivos, la comprensión del ciclo celular y aplicación en los procesos relacionados con formación y reparación de tejidos. Además, se presentan estrategias didácticas con actividades contextualizadas y lecturas que facilitan la transposición de conceptos, el desarrollo habilidades de pensamiento; lo cual tiene como fin mejorar la comprensión, modificar los modelos mentales y contribuir a un aprendizaje significativo del ciclo celular y su función en el organismo. Abstract. Classroom proposal: The cell cycle and its role in the development, growth, and tissue reparation, is designed for students in cycle three, the population to be studied are seventh graders students from the school Jesús María Aguirre Charry. The proposed class begins with a diagnosis of previous concepts, essential for understanding the cell cycle from which the cognitive problems presented in students are defined. As a second step, the class proposes a reinforcement phase, which is expected to improve the cognitive conflicts and the comprehension of the cell cycle; and finally, its application in the processes related to formation and reparation of tissues. This proposal, also presents teaching strategies and contextualized reading activities which main goal is facilitate the transposition of concepts and the development of critical thinking skills that can contribute to modify the mental framework of the students and develop a meaningful learning of the cell cycle and its role in the body. Maestría

Deregulation of signal transduction pathways frequently confers selective biological advantages to tumors. Phosphoinositides play an essential role in numerous cellular functions and, among the enzymes implicated in these processes, phosphoinositide-specific phospholipase C β1 (PI-PLCβ1) is one of the key regulators. In the present study, a fluorescence in situ hybridization (FISH) approach was used to investigate PI-PLCβ1 gene copy number alterations in various types of breast cancer differing in their invasiveness and proliferative activity, according to their mitotic index. At the molecular level, we also performed both real-time PCR and immunohistochemical analyses on PI-PLCβ1 to further investigate its expression in primary breast cancers. Finally, we analyzed the correlation between PI-PLCβ1 gene copy number and clinicopathological parameters. Our results show that most of our cases had aneusomies on the PI-PLCβ1 locus (20p12) and amplification of this specific region was the most frequent alteration observed. Our findings also indicate that the amplification of the region containing the PI-PLC β1 gene was mostly related to the mitotic index, rather than to the invasion status. Finally, even though our case series is limited, PI-PLCβ1 gene amplification seems to be correlated to clini - copathological parameters. cular markers to better characterize this tumor. A number of different factors are involved in breast carcinoma pathogenesis, making a correct biopathological characterization essential to determine tumor aggressiveness and to identify the most appro- priate therapy. Moreover, as numerous genetic alterations are preserved throughout the evolution of breast cancer and a strong correlation exists between the presence of precursor lesions and the risk of developing invasive carcinoma (2-5), the discovery of new molecular targets could play an important role in the early diagnosis and monitoring of this disease. In breast cancer, as well as in other tumors, the deregulation

Item does not contain fulltext Walker-Warburg syndrome (WWS) is an autosomal recessive disorder characterized by congenital muscular dystrophy, structural eye abnormalities and severe brain malformations. We performed an immunohistochemical and electron microscopy study of a muscle biopsy from a patient affected by WWS carrying a homozygous frameshift mutation in O-mannosyltransferase 1 gene (POMT1). alpha-Dystroglycan glycosylated epitope was not detected in muscle fibers and intramuscular peripheral nerves. Laminin alpha2 chain and perlecan were reduced in muscle fibers and well preserved in intramuscular peripheral nerves. The basal lamina in several muscle fibers showed discontinuities and detachment from the plasmalemma. Most nuclei, including myonuclei and satellite cell nuclei, showed detachment or complete absence of peripheral heterochromatin from the nuclear envelope. Apoptotic changes were detected in 3% of muscle fibers. The particular combination of basal lamina and nuclear changes may suggest that a complex pathogenetic mechanism, affecting several subcellular compartments, underlies the degenerative process in WWS muscle.