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Proteínas do Tegumento de Abelhas Apis mellifera em Metamorfose: Identificação por Espectrometria de Massa / Integument Protein of Honeybee Apis mellifera under Metamorphosis: Identification by Mass SpectrometryAndré Fernando Ditondo Micas 19 December 2012 (has links)
Como qualquer inseto holometábolo, a abelha Apis mellifera sofre metamorfose completa, apresentando grandes mudanças na forma e fisiologia quando passa do estágio larval para o estágio de pupa (muda metamórfica). Após esta muda, com o prosseguimento do desenvolvimento, o tegumento pupal (cutícula e a epiderme subjacente), extensivamente remodelado, é substituído pelo tegumento adulto, definitivo, que passa por intensa melanização e esclerotização. Eletroforese bidimensional e espectrometria de massas foram utilizadas neste trabalho para caracterizar as mudanças do padrão proteico no tegumento em desenvolvimento de operárias e zangões. No total foram identificadas 51 proteínas diferentes no tegumento torácico extraído de larvas, pupas e adultos (adultos-faratos). Quatorze proteínas foram identificadas como genuinamente cuticulares: Apidermina-3,1-like, Apidermina-2, Cuticular proteins analogous to peritrophins-3C e 3D, AmelCPR3, 12, 16 e 27, Glicoproteína SgAbd-2-like, e cinco outras proteínas homólogas à proteínas cuticulares de outras espécies de insetos contendo um domínio de ligação à quitina. As proteínas diferiram principalmente quantitativamente entre as fases de desenvolvimento e sexo, e poucas diferenças qualitativas foram observadas. Por exemplo, Apidermina-2 é típica de tegumentos fortemente esclerotizados e pigmentados. As diferenças quantitativas foram destacadas pela comparação da abundância de algumas proteínas e seus respectivos RNA mensageiros (utilizando RT-PCR em tempo real) entre as fases de desenvolvimento e entre os sexos. Várias proteínas cuticulares mostraram mais de uma forma molecular, aparentemente derivadas de modificações pós-traducionais. Além de conferir suporte experimental para a validação de genes de A. mellifera preditos, ou não-anotados, nossos dados forneceram novas informações sobre as proteínas que atuam no tegumento em desenvolvimento. / As a holometabolous insect, the honey bee undergoes complete metamorphosis, displaying a marked change in shape and physiology when passing from the larval to the pupal stage (metamorphic molt). As development progresses, the extensively remodeled pupal integument (cuticle and subjacent epidermis) is replaced by the adult integument, which undergoes intense sclerotization and melanization. Two-dimensional electrophoresis and mass spectrometry were here used to characterize the changing protein patterns in the developing integument of workers and drones. Overall, we identified 51 different proteins in the thoracic integument extracted from larvae, pupae and adults (pharate adults). Fourteen proteins were identified as genuine cuticular proteins: Apidermin-3,1-like protein, Apidermin-2, Cuticular Proteins Analogous to Peritrophins-3C and 3D, AmelCPR3, 12, 16 and 27, Glycoprotein SgAbd-2-like, and 5 other proteins homologous to cuticular proteins from other insect species, and containing the chitin-binding domain. Integument proteins mainly differed quantitatively among the developmental stages and sexes, although few qualitative differences have also been detected. For example, Apidermin-2 is typical of the heavily pigmented and sclerotized integument. The quantitative differences were highlighted by comparing the levels of some of these proteins and their respective mRNAs (using RT-qPCR) among the developmental phases and between sexes. It is noteworthy that several cuticle proteins showed more than one molecular form, apparently derived from post-translational modifications. In addition to give experimental support for validation of predicted, or unannotated, honey bee genes, our data provided new information on proteins acting in the metamorphosing integument.
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Caracterização da região codificadora e análise de expressão de Hexamerinas durante o desenvolvimento de Apis mellifera / Coding region characterization and Hexamerins expression during Apis mellifera developmentJuliana Ramos Martins 28 August 2008 (has links)
Os cDNAs dos genes codificadores das hexamerinas HEX 70a, HEX 70c e HEX 110 de Apis mellifera foram sintetizados a partir de RNA total, clonados e suas regiões codificadoras foram totalmente seqüenciadas. As análises in silico dos produtos de tradução mostraram que as respectivas subunidades protéicas contêm os domínios conservados N, M e C, típicos de hemocianinas, e que em HEX 110, mas não nas outras subunidades, o domínio C foi interrompido pela inserção de uma seqüência repetitiva de aminoácidos. Análises de similaridade indicaram que os genes codificadores de hexamerinas derivaram de eventos de duplicação e diversificação a partir de um gene ancestral, resultando em múltiplos parálogos. Nossas análises também evidenciaram que HEX 110 é uma proteína rica em glutamina/ácido glutâmico e que HEX 70a e HEX 70c são compostas por mais de 15% de aminoácidos aromáticos e, portanto, integram a classe das arilforinas. A expressão temporal destes genes, e também do gene codificador de outra hexamerina de A. mellifera, hex 70b, previamente caracterizado, foi analisada qualitativa e quantitativamente durante o desenvolvimento de operárias, rainhas e zangões. Concomitantemente, a abundância dos respectivos polipeptídeos no corpo gorduroso ou hemolinfa foi examinada por SDS-PAGE ou Western Blot. Os quatro genes de hexamerinas se expressam no corpo gorduroso de operárias, rainhas e zangões principalmente durante o estágio larval. A modulação da expressão destes genes mostra semelhanças durante a transição larval-pupal de operárias, rainhas e zangões, com altos níveis de transcritos no último estágio larval e baixos níveis no início da fase pupal. No entanto, a quantidade relativa de transcritos de hex 70a, hex 70b e hex 110 na fase de alimentação do último estágio larval (L5F) é significantemente menor nas rainhas que nas operárias, o que sugere participação das respectivas proteínas no processo de diferenciação de castas. Durante o estágio larval, as quatro diferentes subunidades de hexamerinas são armazenadas na hemolinfa onde, aparentemente, cumprem a função de proteínas de estocagem e, portanto, constituem fonte de aminoácidos para utilização em processos inerentes ao desenvolvimento pupal. No entanto, a expressão de hex 70a se estende até ao estágio adulto de operárias, rainhas e zangões, e neste estágio, as fêmeas e os zangões exibem perfis distintos de expressão. No corpo gorduroso de operárias, mas não no de rainhas e zangões, a expressão de hex 110 também ocorre durante o estágio adulto. A expressão de hex 70a e hex 110 no corpo gorduroso mostrou-se limitada pela disponibilidade de nutrientes: operárias alimentadas com uma dieta protéica apresentaram níveis significantemente maiores de ambos transcritos que aquelas que receberam dieta desprovida de proteínas, assim evidenciando que os processos de transcrição e tradução são nutricionalmente regulados. Além disto, os níveis de transcritos de hex 70a e hex 110 aumentam no corpo gorduroso de abelhas operárias portadoras de ovários ativos, sugerindo que estes genes têm função associada à reprodução. Em A. mellifera, o corpo gorduroso não é o único sítio de expressão dos genes de hexamerinas. Transcritos de hex 70a, hex 70b e hex 110 foram detectados também nas gônadas em desenvolvimento de operárias, rainhas e zangões, sugerindo uma função na diferenciação dos ovários e maturação dos testículos. Nossos resultados indicam que as hexamerinas codificadas por estes genes têm funções alternativas no ciclo de vida de abelhas A. mellifera, além de servir como fonte de aminoácidos para a metamorfose. / The cDNAs encoding the hexamerins HEX 70a, HEX 70c and HEX 110 of Apis mellifera were synthesized from total RNA isolated, cloned and their coding region were completely sequenced. In silico analyses of the translation products showed that the respective protein subunits contain the conserved domains N, M and C, typical of hemocyanins, and that in HEX 110, but not in the other subunits, the C domain is interrupted by a repetitive amino acid sequence. Analyses of similarity suggested that in the honey bee, the four hexamerin genes derived by duplication events and diversification from an ancestral gene, resulting in multiple paralogs. Our analyses also showed that HEX 110 is rich in glutamine/glutamic acid and that HEX 70a and HEX 70c are composed by more than 15% of aromatic amino acids and, therefore, integrate the arylphorin class of hexamerins. The temporal expression of these genes, and also of the gene encoding a previously characterized hexamerin of A. mellifera, hex 70b, was analyzed qualitatively and quantitatively during the development of worker bees, queens and drones. Concomitantly, the abundance of the respective polypeptides in the fat body or hemolymph was examined by SDS-PAGE or Western Blot. The four hexamerin genes are expressed in the fat body mainly during larval stage. The modulation of the expression of these genes shows similarities during the larval-pupal transition of worker bees, queens and drones, with high levels of transcripts in the last larval instar and low levels in newly ecdysed pupae. However, the relative quantity of transcripts of hex 70a, hex 70b and hex 110 in the feeding phase of the last larval instar (L5F) is significantly lower in queens than in worker bees, suggesting the participation of the respective proteins in the process of caste differentiation. During the larval stage, the four different hexamerin subunits are stored in the hemolymph where, seemingly, they perform the function of storage proteins and hence, constitute source of amino acids for pupal development. Nevertheless, the expression of hex 70a is extended until the adult stage of worker bees, queens and drones and, in this stage, the female bees and the drones show distinct expression profiles. In the fat body of worker bees, but not in queens and drones, the expression of hex 110 also occurs during the adult stage. The expression of hex 70a and hex 110 in the adult fat body was proven to be limited by the availability of nutrients: worker bees fed with a protein diet showed significantly higher levels of both transcripts than the ones that received a diet which was poor in protein, thus evidencing that the transcription and translation processes are nutritionally-regulated. Additionally, the transcripts level of hex 70a and of hex 110 increase in the fat body of worker bees with active ovaries, suggesting that these genes have function associated with reproduction. In A. mellifera, the fat body is not the only site of expression of hexamerins genes. Transcripts of hex 70a, hex 70b and hex 110 were detected also in developing gonads of worker bees, queens and drones, suggesting that they have a function in ovary differentiation and testis maturation. Our results indicated that the hexamerins encoded by these genes have alternate functions in the life cycle of A. mellifera honey bees, besides serving as a source of amino acids to metamorphosis.
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Busca de Inibidores Naturais Contra o Veneno de Apis Mellifera / A Search for Natural Inhibithiros Against Apis mellifera VenomDaniel Macedo de Melo Jorge 31 October 2008 (has links)
Os insetos são os mais numerosos animais encontrados no mundo, com mais de 675 mil espécies conhecidas. Pertencentes à ordem Hymenoptera, da superfamília Apoidea, as abelhas são encontradas distribuídas em aproximadamente 20 mil espécies. No Brasil estima-se que existam 1.700 espécies. Uma das principais espécies é a Apis mellifera, com ocorrência cosmopolita. A Apis mellifera, popularmente conhecida como abelha africanizada, é agressiva, enxameia várias vezes ao ano e utiliza uma grande variedade de locais para nidificar. Esse comportamento aumenta o contato direto entre o inseto e a população, aumentando o número de acidentes. Os acidentes com abelhas representam um problema de saúde pública em diversos países do mundo pela freqüência com que ocorrem e pela mortalidade que ocasionam. O presente estudo propõe a busca por inibidores naturais contra o veneno de abelhas. Um sistema e uma base de dados foram desenvolvidos para a integração entre dados de plantas medicinais antivenenos e os venenos de abelhas. As atividades anti-hemorrágica, anti-proteolítica, anti-miotóxica, antifosfolipase e anti-edema de plantas medicinais antiveneno foram analisadas por meio de ensaios farmacológicos. As possíveis interações entre as toxinas Melitina e Fosfolipase A2 com inibidores foram avaliadas, através do docking virtual. O banco de dados, denominado Bee Venom, foi implementado e os dados de bancos de dados públicos foram inseridos no sistema. O sistema foi liberado para acesso público no endereço eletrônico http://gbi.fmrp.usp.br/beevenom/. Durante a análise da proteína Melitina foram encontradas as regiões da proteína em que os possíveis inibidores devem interagir e identificadas as propriedades químicas que os inibidores devem possuir para interagir corretamente com a Melitina. Nas análises in silico foi possível identificar 10 possíveis inibidores que interagiram corretamente com o sítio ativo da Fosfolipase A2. Algumas espécies do Banco de Germoplasma da FMRP/USP foram obtidas e utilizadas nos experimentos de atividade fosfolipásica indireta e de Edema, sendo possível observar inibição do veneno total e da proteína Fosfolipase A2. Os compostos sintéticos e inibidores avaliados não causaram inibição em todos os experimentos avaliados. Já as plantas obtidas no laboratório de Toxinas Animais e Inibidores Naturais e Sintéticos causaram inibição do veneno total e da proteína Fosfolipase A2. / Insects are the most numerous animals worldwide, with more than 675 thousand known species. Belonging to Hymenoptera order, Apoidea, superfamily, bees are found distributed in approximately 20 thousand species. In Brazil there are about 1,700 species. One of the major species is Apis mellifera, with cosmopolitan occurrence. Apis mellifera, popularly known as Africanized bee, is aggressive, swarm several times per year and uses a great variety of locals to nidificate. This behavior raises the contact between the insect and the population, increasing the accidents numbers. Bee accidents represent a public health problem in many countries because of their frequency and mortality. The present study proposes to search for natural inhibitors of bee venom. A system and a data base have been developed to integrate anti-venom medicinal plants data and bee venoms. Plants activities against venom have been evaluated by farmacological assays, such as anti-hemorraghic, anti-proteolitic, anti-myotoxicity, anti-Phospholipase and anti-edema. The possible interactions between Melittin and Phospholipase A2 toxins with inhibitors have been evaluated by virtual docking. The data base, denominated Bee Venom, was implemented and the data from public data bases have been inserted in the system. The system was released to public access in the following address http://gbi.fmrp.usp.br/beevenom/. In Melittin analysis the protein regions which the inhibitors may act have been found and also the chemical properties that the inhibitors must have to interact with Melitina have been identified. During in silico analysis it was possible to identify 10 possible inhibitors that interacted well with Phospholipase A2 active site. Some plants species from FMRP/USP Germoplam Bank have been obtained and used in the indirect Phospholipase activity and edema, being possible to observe inhibitions of total venom and Phospholipase A2 protein. The synthetic compounds and inhibitors evaluated did not cause inhibition in any experiments. However, the plants obtained on Animals Toxins and Natural and synthetic Inhibitors laboratory have caused inhibition of total venom and Phospholipase A2 protein.
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Genes cuticulares diferencialmente expressos durante eventos da metamorfose de Apis mellifera / Microarray analysis of genes expressed in the context of Apis mellifera metamorphosisMichelle Prioli Miranda Soares 06 July 2012 (has links)
A cutícula dos insetos é composta principalmente por uma variedade de proteínas que interagem com filamentos de quitina, um polímero de N-acetilglicosamina, para formar um envoltório rígido que protege e dá forma ao organismo. O crescimento dos insetos depende da renovação periódica da cutícula, que se desprende durante a apólise e é digerida enquanto a epiderme sintetiza uma nova cutícula substituta. Tal renovação caracteriza a muda e metamorfose e é coordenada por hormônios, com destaque para os ecdisteróides. O atual trabalho objetivou caracterizar a expressão diferencial de genes do tegumento (cutícula e epiderme subjacente), além de elucidar aspectos de regulação e função no contexto da muda e metamorfose, com foco nos genes codificadores de proteínas estruturais e enzimas cuticulares. Para este fim, utilizamos o tegumento de fases específicas da muda pupal-adulta, isto é, de pupas (Pw), de pupas em apólise (Pp) e de adultas faratas (Pbl) para análises de microarrays de cDNA. As análises dos microarrays mostraram 761 e 1173 genes diferencialmente expressos nos tegumentos de adultas faratas (Pbl) em comparação com pupas (Pw) ou pupas em apólise (Pp), respectivamente. A categorização destes genes, segundo os critérios do Gene Ontology, distinguiu totalmente o tegumento de adultas faratas (Pbl) dos tegumentos de pupas (Pw) ou pupas em apólise (Pp) tanto em relação ao critério Processo Biológico quanto em relação à Função molecular, evidenciando grande mudança na expressão gênica durante a construção do exoesqueleto definitivo nas adultas faratas (Pbl). Os microarrays mostraram aumento estatisticamente significante da expressão de 24 genes cuticulares no tegumento de adultas faratas. Este resultado foi validado por RT-PCR em tempo real (qRT-PCR) para 23 destes genes (AmelCPR3, AmelCPR4, AmelCPR6, AmelCPR14, AmelCPR15, AmelCPR17, AmelCPR23, AmelCPR24, AmelCPR25, AmelCPR28, AmelCPR29, AmelCPR30, apd-1, apd-2, apd-3, CPLCP1, Am-C, Am-D, AmelTwdl1, AmelTwdl2, GB12449, GB12811 e GB11550), e por RT-PCR semiquantitativa para o gene Amlac2. Além disto, a maior expressão de outros 2 genes cuticulares (AmelCPR1 e AmelCPR2) em adultas faratas foi demonstrada por qRT-PCR. Estes genes cuticulares positivamente regulados no tegumento de adultas faratas (Pbl) devem estar envolvidos com a formação e diferenciação do exoesqueleto definitivo. O aumento da expressão gênica neste período da muda (Pbl) é regulado pela variação do título de ecdisteróides e ocorre enquanto o título deste hormônio decai, após ter atingido o pico indutor da apólise na fase de desenvolvimento precedente (Pp). Ao contrário, as análises por qRT-PCR mostraram que 2 outros genes cuticulares (AmelCPF1 e AmelCPR1) são negativamente regulados no tegumento de adultas faratas em comparação com pupas, sugerindo que são específicos de cutícula pupal. Estes genes foram inibidos pelo aumento dos níveis de ecdisteróides, que induz a apólise. Vinte e um entre os 24 genes cuticulares diferencialmente expressos nos microarrays codificam proteínas pertencentes às famílias CPF, CPR, Apidermina, CPLCP, Análoga a peritrofina e Tweedle. Os outros 3 genes diferencialmente expressos (GB12449, GB12811, GB11550) não tinham sido ainda caracterizados como genes cuticulares. Dois deles, GB12449 e GB12811, foram sequenciados para validação da predição e para a caracterização das respectivas estruturas genômicas. Experimentos de hibridação in situ com sonda fluorescente (FISH) nos permitiram localizar altos níveis de transcritos destes genes no citoplasma de células da epiderme de adultas faratas, sugerindo fortemente sua natureza cuticular e envolvimento na construção do exoesqueleto definitivo. O presente estudo consiste na primeira análise global de expressão de genes do tegumento de uma espécie de himenóptero social. Os resultados apresentados levaram à identificação de genes com expressão associada à muda pupal-adulta e formação do exoesqueleto definitivo. Este trabalho contribui com novos dados moleculares para o aprofundamento do conhecimento da metamorfose de A. mellifera. / The insect cuticle is mainly composed of proteins that interact with chitin filaments to form a rigid structure that protects and shapes the organism. Insects grow through the periodic renewal of the cuticle, which is shed at each apolysis episode, and subsequently digested while the epidermis synthesizes the cuticle of the next stage. These molting events are coordinated by hormones, mainly ecdysteroids. The current work aimed to characterize differential gene expression in the integument (cuticle and underlying epidermis) during the ecdysteroid-regulated pupal-to-adult molt. Special attention was given to the structure and expression of genes encoding proteins and enzymes involved in cuticle formation and differentiation. To achieve these goals, we used thoracic integument of newly-ecdysed pupae (Pw), pupae in apolysis (Pp) and pharate adults (Pbl) in cDNA microarray analyses. The microarray analysis showed 761 and 1173 differentially expressed genes in the pharate adult integument (Pbl) in comparison to pupae (Pw) or pupae in apolysis (Pp), respectively. Gene Ontology terms for Biological Process and Molecular Function completely distinguished the integument of pharate adults (Pbl) from the integument of pupae (Pw) or pupae in apolysis (Pp). The microarray analysis discriminated 24 cuticular genes with a significant expression increase in the pharate adult integument. This was validated by real time RT-PCR analysis (qRT-PCR) for 23 of these genes (AmelCPR3, AmelCPR4, AmelCPR6, AmelCPR14, AmelCPR15, AmelCPR17, AmelCPR23, AmelCPR24, AmelCPR25, AmelCPR28, AmelCPR29, AmelCPR30, apd-1, apd-2, apd-3, CPLCP1, Am-C, Am-D, AmelTwdl1, AmelTwdl2, GB12449, GB12811 and GB11550), and by semiquantitative RT-PCR for Amlac2. In addition, the increased expression of other two cuticular genes (AmelCPR1 and AmelCPR2) was confirmed by qRT-PCR. These up-regulated cuticular genes in pharate adult integument apparently are involved in adult cuticle formation and differentiation, which occurs while the ecdysteroids titers decay, after reaching the peak that induces apolysis in the preceding phase (Pp). In contrast, two cuticular genes (AmelCPF1 e AmelCPR1) were confirmed by qRT-PCR analysis as negatively regulated in the integument of pharate adults compared to pupae, suggesting that they are specific to pupal cuticle. Therefore, these genes were inhibited by the increasing ecdysteroid levels that induce apolysis. Twenty one of the 24 cuticular genes differentially expressed in the microarrays encode proteins belonging to the CPF, CPR, Apidermin, CPLCP, Analogous to peritrofins and Tweedle families. The other three differentially expressed genes (GB12449, GB12811, GB11550) had not yet been assigned as cuticular genes. Two of them (GB12449 and GB12811) were sequenced, thus allowing prediction validation and gene structure characterization. In situ hybridization experiments using fluorescent probe (FISH) localized high expression of these genes in the pharate adult epidermis, strongly suggesting their involvement in the construction of the adult exoskeleton. This study is the first global gene expression analysis of the integument from a social hymenopteran species. The expression of genes in the integument was associated to the molting process and to the adult exoskeleton formation. This work contributes with new molecular data for a deeper understanding of A. mellifera metamorphosis.
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Caracterização e efeito da variação sazonal da própolis orgânica produzida no sul do Brasil / Characterization and effect of seasonal variation on organic propolis produced in southern BrazilValéria Zatarin Pandolfo 10 November 2014 (has links)
A própolis é um material resinoso produzido pelas abelhas e utilizado na colmeia para o fechamento de fissuras e esterilização dos ambientes internos da colmeia, a qual em média possui cerca de 30% de ceras, 55% de resinas e bálsamos, 10% de óleos voláteis e 5% de pólen. Dentre os constituintes de maior importância encontram-se os compostos fenólicos, em especial os flavonoides, ácidos fenólicos e ésteres, que possuem propriedades biológicas, dentre elas a atividade antioxidante. A variabilidade de compostos com atividade antioxidante, bem como a presença ou ausência dos mesmos é definida pela sua origem geográfica e biodiversidade presente nos arredores da colmeia, sendo que variações sazonais interferem igualmente na proporção de seus constituintes. A própolis utilizada neste estudo foi proveniente do sistema de produção orgânica certificada, as quais faziam parte matas nativas, de preservação permanente, reserva legal ou matas de reflorestamento. Portanto, o objetivo deste trabalho foi avaliar o efeito da sazonalidade e a atividade antioxidante por meio de ensaios de sequestro de radicais livres (ABTS+) e capacidade de absorção de radicais de oxigênio (ORAC) nos anos de 2012 e 2013. Além disso, também foi realizado um estudo de avaliação do teor de cera bruta por vários métodos de extração por soxhlet. Quanto à sazonalidade, foi possível a verificação de diferença entre os anos, sendo que o ano de 2012 foi o que apresentou os maiores resultados para o teor de compostos fenólicos totais (39,57mg/g EAG), ABTS+ (0,781 ?mol Trolox/mg) e ORAC (1,851 ?mol Trolox/mg). Também foi o ano que apresentou as maiores variações entre as estações, onde se destaca o verão, com resultados médios de 46,26 mg/g EAG para teor de compostos fenólicos totais e 0,950 ?mol Trolox/mg para atividade antioxidante pelo método ABTS+. No ano de 2013 houve diferença entre as estações apenas para ORAC, sendo o outono o período de maior média (1,269 ?mol Trolox/mg). As nove metodologias utilizadas para avaliar a porcentagem de cera apresentaram grande variação para a mesma amostra. Quando analisadas pela técnica de CCD-FR, foi possível verificar a presença de sete perfis distintos da própolis. Em relação à composição volátil, o alfa-pineno foi o composto predominante. A análise da composição não volátil por CG-MS mostrou a presença de metil commate B, C e D no sétimo perfil, os quais são conhecidos por, serem antioxidantes, corroborando assim com a boa atividade encontrada para esse perfil. / Propolis is a resinous material produced by bees and used in the hive for closing cracks and sterilizing indoor beehive. Propolis has about 30% wax, 55% resins and balsams, 10% volatile oils and 5% pollen. The phenolic compounds are the most important constituents, namely flavonoids, phenolic acids and esters, which have biological properties, such as antioxidant activity. The variability of compounds with antioxidant activity and their presence or absence are defined by the geographical origin and biodiversity around the hive. Seasonal variations also influence the contents of propolis constituents. In this study, we used propolis from a certified organic production system, which included native forests, permanent preservation areas, legal reserve forests or reforestation areas. This study investigated the effect of seasonality and antioxidant activity by testing the capture of free radicals (ABTS+) and oxygen radicals absorption capacity (ORAC) in the years 2012 and 2013. In addition, we evaluated wax contents using various methods by soxhlet extraction. We observed differences of seasonality between the two years, the year 2012 showed the greatest total contents of phenolic compounds (39.57 mg/g EAG), ABTS+ (0.781 ?mol Trolox/mg) and ORAC (1.851 ?mol Trolox/mg). In the same year also showed the greatest variations among the seasons, especially the summer, with average scores of 46.26 mg/g EAG for total phenolic compounds and 0.950 ?mol Trolox/mg for antioxidant activity in the ABTS+ method. In 2013 there was a difference between seasons just in ORAC. The fall showed the highest average (1.269 ?mol Trolox/mg). The nine methodologies used to evaluate the percentage of wax varied greatly for the same sample. The TLC-RF showed the presence of seven distinct profiles of propolis. Alpha-pinene was the predominant compound of the volatile content. The analysis of the nonvolatile composition by GC-MS showed the presence of methyl commate B, C and D in the 7th profile, which are antioxidants, thus, confirming the good activity found for this profile.
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An APIfication Approach to Facilitate the Access and Reuse of Open DataGonzález Mora, César 10 September 2021 (has links)
Nowadays, there is a tendency to publish data on the Web, due to the benefits it brings to the society and the new legislation that encourage the opening of data. These collections of open data, also known as datasets, are typically published in open data portals by governments and institutions around the world in order to make it open -- available on the Web in a free and reusable manner. The common behaviour tends to be that publishers expose their data as individual tabular datasets. Open data is considered highly valuable because promoting the use of public information produces transparency, innovation and other social, political and economic benefits. Especially, this importance is also considerable in situational scenarios, where a small group of consumers (developers or data scientists) with specific needs require thematic data for a short life cycle. In order that these data consumers easily assess whether the data is adequate for their purpose there are different mechanisms. For example, SPARQL endpoints have become very useful for the consumption of open data, and particularly, Linked Open Data (LOD). Moreover, in order to access open data in a straightforward manner, Web Application Programming Interfaces (APIs) are also highly recommended feature of open data portals. However, accessing this open data is a difficult task since current Open Data platforms do not generally provide suitable strategies to access their data. On the one hand, accessing open data through SPARQL endpoints is a difficult task because it requires knowledge in different technologies, which is challenging especially for novice developers. Moreover, LOD is not usually available since most used formats in open data government portals are tabular. On the other hand, although providing Web APIs would facilitate developers to easily access open data for reusing it from open data portals’ catalogs, there is a lack of suitable Web APIs in open data portals. Moreover, in most cases, the currently available APIs only allow to access catalog’s metadata or to download entire data resources (i.e. coarse-grain access to data), hampering the reuse of data. In addition, as the open data is commonly published individually without considering potential relationships with other datasets, reusing several open datasets together is not a trivial task, thus requiring mechanisms that allow data consumers to integrate and access tabular open data published on the Web. Therefore, open data is not being used to its full potential because it is not easily accessible. As the access to open data is thus still limited for end-users, particularly those without programming skills, we propose a model-based approach to automatically generate Web APIs from open data. This APIfication approach takes into account the access to multiple integrated tabular datasets and the consumption of data in situational scenarios. Firstly, we focus on data that can be integrated by means of join and union operations. Then, we coin the term disposable Web APIs as an alternative mechanism for the consumption of open data in situational scenarios. These disposable Web APIs are created on-the-fly to be used temporarily by a user to consume specific open data. Accordingly, the main objective is to provide suitable mechanisms to easily access and reuse open data on the fly and in an integrated manner, solving the problem of difficult access through SPARQL endpoints for most data consumers and the lack of suitable Web APIs with easy access to open data. With this approach, we address both open data publishers and consumers, as long as the publishers will be able to include a Web API within their data, and data consumers or reusers will be benefited in those cases that a Web API pointing to the open data is missing. The results of the experiments conducted led us to conclude that users consider our generated Web APIs as easy to use, providing the desired open data, even though coming from different datasets and especially in situational scenarios. / Esta tesis ha sido financiada por la Universidad de Alicante mediante un contrato destinado a la formación predoctoral, y por la Generalitat Valenciana mediante una subvención para la contratación de personal investigador de carácter predoctoral (ACIF2019).
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Trust Factors and Third-Party Web APIs : A survey on what factors influences developers’ trust in third-party web APIs / Förtroendefaktorer och Webb-APIer från tredje part : En undersökning på vilka faktorer som påverkar utvecklares förtroende för webb-APIer från tredje partGorrell, Jordan January 2021 (has links)
Third-party web APIs are becoming ever more popular as the API economy continues to grow. Software developers often integrate them into their own applications. The issue is that even if a developer thoroughly tests that their application works properly with the third-party web API, the owner of that API can completely change the code at any time, or take the API offline altogether, either temporarily or permanently. This makes for potentially less stable or reliable applications. This report attempts to determine what some of the factors are that most influence software developers’ trust in any given third party Web API. To do this, 42 individuals involved with software development were surveyed. Documentation and reliability came through as the strongest factors influencing their trust, but there is no general consensus on other factors. Further work could be done to confirm that these two factors are what influence developer trust the most, as well as work to determine which factor sought to influence developers’ trust in any given third-party web API, and thus work towards more reliable applications being developed as the API economy continues to grow.
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Comportement reproducteur et communication sexuelle phéromonale chez les abeilles du genre Apis. / Mating behaviour and pheromonal sex communication in honey bees of the Apis genusBastin, Florian 12 December 2017 (has links)
Pendant la période de reproduction, les mâles et les reines d’abeilles du genre Apis se regroupent au sein de congrégations. Ces congrégations qui ont lieu haut dans le ciel sont particulièrement difficiles à étudier sur le terrain. Nous avons donc développé un simulateur de marche permettant de tester l’attractivité de signaux olfactifs chez l’abeille domestique, A. mellifera. Avec ce dispositif, notre travail montre qu’une odeur dégagée par un groupe de mâles en âge de se reproduire attire les autres mâles et les reines vierges. Cette interattraction des mâles est dépendante de l’âge et apparaît uniquement chez les mâles matures sexuellement (12-15 jours). En parallèle, des extraits chimiques de mâles ont été effectués et permettent de proposer des molécules candidates possiblement impliquées dans l’attraction des mâles et des reines vierges. Ce travail conforte l’hypothèse d’une phéromone sexuelle/d’agrégation émise par les mâles sexuellement matures et qui jouerait un rôle dans la formation et le maintien des congrégations. Nous nous sommes ensuite intéressés à l’évolution de la communication sexuelle phéromonale chez 5 espèces du genre Apis. Nous avons ainsi analysé l’organisation neuroanatomique du lobe antennaire (premier centre olfactif) des mâles. Les données montrent des différences marquées dans le nombre et la position des macroglomérules, structures spécialisées dans la détection des phéromones sexuelles. Les espèces d’abeilles naines (A. florea) et d’abeilles géantes (A. dorsata) possèdent 2 macroglomérules et les abeilles de cavités (A. cerana, A. koshevnikovi et A. mellifera) entre 3 et 4 macroglomérules, suggérant une complexification des échanges sexuels phéromonaux dans ce groupe. Cependant, toutes les espèces du genre Apis présentent un même macroglomérule, connu pour détecter le composé majeur de la phéromone de reine, le 9-ODA, chez Apis mellifera. Ce travail établit l’existence d’une phéromone de mâles chez les abeilles du genre Apis et suggère une influence des signaux olfactifs dans l’isolement reproducteur et la spéciation de ces abeilles. / During the mating season, honey bee males (drones) and queens gather at congregation areas high up in the air, which make their onsite study arduous. We developed a walking simulator to test the attractiveness of olfactory signals under controlled laboratory conditions in honey bees A. mellifera. Our results show that mature drones and virgin queens are both attracted by groups of sexually mature drones. This attraction between drones is influenced by sexual maturity, as only sexually mature drones (12-15 days old) display an inter-attraction. In parallel, we performed analyses of drones’ chemical profiles and proposed a number of candidates molecules possibly involved in olfactory attraction of virgin males and queens. This study supports the existence of a sexual/aggregation pheromone emitted by sexually mature drones, which may play a pivotal role in the formation and maintenance of congregations. We were then interested in the evolution of pheromonal sex communication in 5 species of the genus Apis. We thus analyzed the neuroanatomical organization of the drone antennal lobe (primary olfactory center). Our data revealed marked differences in the number and position of macroglomeruli, insects’ functional units dedicated to sex pheromone processing. Dwarf (A. florea) and giant (A. dorsata) honey bee species possess 2 macroglomeruli while cavity nesting bees (A. cerana, A. koshevnikovi and A. mellifera) present 3 or 4 macroglomeruli, suggesting an increase in the complexity of sexual communication in the genus Apis. Interestingly, one macroglomerulus, which is dedicated to the detection of the queen pheromone, 9-ODA in A. mellifera, was conserved in all species. This work establishes the existence of a male pheromone in Apis species and suggests an influence of olfactory signals in the reproductive isolation and speciation of these bees.
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Transcriptional markers of sub-optimal nutrition in developing Apis mellifera nurse workersCorby-Harris, Vanessa, Jones, Beryl, Walton, Alexander, Schwan, Melissa, Anderson, Kirk January 2014 (has links)
BACKGROUND:Honey bees (Apis mellifera) contribute substantially to the worldwide economy and ecosystem health as pollinators. Pollen is essential to the bee's diet, providing protein, lipids, and micronutrients. The dramatic shifts in physiology, anatomy, and behavior that accompany normal worker development are highly plastic and recent work demonstrates that development, particularly the transition from nurse to foraging roles, is greatly impacted by diet. However, the role that diet plays in the developmental transition of newly eclosed bees to nurse workers is poorly understood. To further understand honey bee nutrition and the role of diet in nurse development, we used a high-throughput screen of the transcriptome of 3day and 8day old worker bees fed either honey and stored pollen (rich diet) or honey alone (poor diet) within the hive. We employed a three factor (age, diet, age x diet) analysis of the transcriptome to determine whether diet affected nurse worker physiology and whether poor diet altered the developmental processes normally associated with aging.RESULTS:Substantial changes in gene expression occurred due to starvation. Diet-induced changes in gene transcription occurring in younger bees were largely a subset of those occurring in older bees, but certain signatures of starvation were only evident 8day old workers. Of the 18,542 annotated transcripts in the A. mellifera genome, 150 transcripts exhibited differential expression due to poor diet at 3d of age compared with 17,226 transcripts that differed due to poor diet at 8d of age, and poor diet caused more frequent down-regulation of gene expression in younger bees compared to older bees. In addition, the age-related physiological changes that accompanied early adult development differed due to the diet these young adult bees were fed. More frequent down-regulation of gene expression was observed in developing bees fed a poor diet compared to those fed an adequate diet. Functional analyses also suggest that the physiological and developmental processes occurring in well-fed bees are vastly different than those occurring in pollen deprived bees. Our data support the hypothesis that poor diet causes normal age-related development to go awry.CONCLUSION:Poor nutrition has major consequences for the expression of genes underlying the physiology and age-related development of nurse worker bees. More work is certainly needed to fully understand the consequences of starvation and the complex biology of nutrition and development in this system, but the genes identified in the present study provide a starting point for understanding the consequences of poor diet and for mitigating the economic costs of colony starvation.
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Biological effects and effect mechanisms of neonicotinoid pesticides in the bumble bee Bombus terrestrisLaycock, Ian January 2014 (has links)
Bumble bees provide valuable pollination services to many agricultural crops and wild flower species. Consequently, evidence that wild populations are in decline has caused widespread concern. Among multiple causal factors, some have singled out neonicotinoid pesticides as potentially a major contributor to these declines. Bumble bees are exposed to neonicotinoids, such as imidacloprid and thiamethoxam, whilst foraging for nectar and pollen from treated crops. For neonicotinoids to cause population decline, the typical residues that bumble bees encounter in the field (defined here as between 1–12 μg kg-1) should be capable of reducing colony success by detrimentally impacting demographically relevant endpoints such as reproduction and worker performance. Whether field-realistic neonicotinoids are capable of causing such effects is yet to be fully established. The overall aim of this thesis was to investigate the effects of field-realistic neonicotinoids on endpoints of demographic importance and improve understanding of the effect mechanisms of neonicotinoids in bumble bees. Laboratory experiments were conducted with Bombus terrestris L. exposed to dietary neonicotinoids up to 98 μg kg-1. Results showed that food consumption and production of brood (eggs and larvae) in queenless B. terrestris microcolonies were significantly reduced by the two highest concentrations of imidacloprid and thiamethoxam tested (39, 98 μg kg-1), but only imidacloprid produced a negative effect when concentrations were in the typical field-realistic range. Imidacloprid’s affect on microcolonies was mirrored in queenright colonies where field-realistic concentrations substantively reduced both feeding and brood production. It was postulated that the detrimental effects of imidacloprid on brood production emerge principally from nutrient limitation imposed by the failure of individuals to feed. Removing imidacloprid from the bees’ diet resulted in the recovery of feeding and brood production in queenright colonies, even when previously exposed to high doses (98 μg kg-1). Investigation into the effect mechanisms of imidacloprid in B. terrestris revealed that cytochrome P450 enzymes are not important for metabolism of the neonicotinoid in adult workers. A transcriptomic analysis indicated B. terrestris exhibit a general stress response to imidacloprid, characterised by the alteration in expression of genes involved in, for example, metabolism and storage of energy. The thesis findings raise further concern about the threat of imidacloprid to wild bumble bees. However, they also suggest that some demographically important endpoints are resilient to imidacloprid as a realistic pulsed exposure, and that bumble bees may be less sensitive to field-realistic concentrations of thiamethoxam. Further research, which is required to fully establish the demographic consequences for bumble bees of exposure to neonicotinoids, can be developed based on the foundation of work presented here.
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