A comparative study of digestive cells in different midgut regions of stingless bees (Hymenoptera: Apidae: Meliponinae)

Ultrastructure of the digestive cells was analyzed in three midgut regions (anterior, middle and posterior) of stingless bees. Variations occurs in the presence of lipid inclusions in the cells from posterior midgut and presence of double-membraned vesicles associated to microvilli in the anterior midgut. However, basal plasmic membrane infoldings and augmentation of surface area achieved by microvilli are very similar in all midgut regions. These results not supported the existence of fluid fluxes in the ectoperitrophic space and suggest that digestive cells in stingless bees are polifunctional, that is, there is not midgut region specialized in secretion or absorption as observed in other insects.

Cell death in ovarioles causes permanent sterility in Frieseomelitta varia worker bees

Frieseomelitta varia worker bees do not lay eggs even when living in queenless colonies, a condition that favors ovary development and oviposition in the majority of highly social bees. The permanent sterility of these worker bees was initially attributed to a failure in ovary morphogenesis and differentiation. Using transmission electron microscopy we found that at the beginning of the pupal phase the ovaries of F. varia workers are formed by four ovarioles, each of them composed of 1) a terminal filament at the apex of the ovarioles, containing juxtaposed and irregularly shaped cells, 2) a germarium with clusters of cystocytes and prefollicular cells showing long cytoplasmic projections that envelop the cystocyte clusters, 3) fusiform interfollicular and basal stalk precursor cells, and 4) globular, irregularly contoured basal cells with large nuclei. However, during the pupal phase an accentuated and progressive process of cell death takes place in the ovarioles. The dying cells are characterized by large membrane bodies, electron-dense apoptotic bodies, vacuoles, vesiculation, secondary lysosomes, enlarged rough endoplasmic reticulum cisternae, swollen mitochondria, pycnotic nuclei, masses of chromatin adjacent to the convoluted nuclear envelope, and nucleoli showing signs of fragmentation. Cell death continues in ovarioles even after the emergence of the workers. Once they become nurse bees, the ovaries have become transformed into a cell mass in which structurally organized ovarioles can no longer be identified. In F. varia workers, ovariole cell death most certainly is part of the program of caste differentiation.

Reciprocal interference between ants and stingless bees attending the honeydew-producing homopteran Aetalion reticulatum (Homoptera: Aetalionidae)

We evaluated the reciprocal effects between foragers of the ants Camponotus crassus and of the stingless bees Trigona hyalinata on aggregations of the honeydew-producing treehopper Aetalion reticulatum. The interactions were observed in Bauhinia variegata (Caesalpiniaceae) and Mangifera indica (Anacardiaceae) trees. We recorded the presence/absence of each attendant species in homopteran aggregations to test if the observed co-occurrence is lower than that expected by chance. An exclusion experiment was performed in which each attendant species was excluded from aggregations in order to test if an attendant species is more likely to occupy aggregations where the other attendant is not present. We also recorded the number of individuals of each attendant species in homopteran aggregations to search for any correlation between homopteran and attendant abundances. Additionally, we performed experiments using termites (Termitidae, Isoptera) as models to verify if the attendant species have the potential to defend A. reticulatum against natural enemies. The co-occurrence of attendant species was lower than that expected by chance. Homopteran aggregations without stingless bees were more visited by ants than those in which T. hyalinata was present, and vice-versa. The abundance of stingless bees was proportional to homopteran abundance, while ants abundance was not correlated to homopteran abundance. Both attendant species attacked the natural enemies models when we glued the termites ca. 1 cm away from homopteran aggregations, but only ants removed termites glued 5-7 cm away from aggregations. We suggest that the effects of non-formicid attendants should be included as another factor influencing the costs and benefits of ant-homopteran interactions, since honeydew availability for ants also depends on the presence and behavior of interspecific attendants.

Anticancer effects of geopropolis produced by stingless bees on canine osteosarcoma cells in vitro

Geopropolis is produced by indigenous stingless bees from the resinous material of plants, adding soil or clay. Its biological properties have not been investigated, such as propolis, and herein its cytotoxic action on canine osteosarcoma (OSA) cells was evaluated. OSA is a primary bone neoplasm diagnosed in dogs being an excellent model in vivo to study human OSA. spOS-2 primary cultures were isolated from the tumor of a dog with osteosarcoma and incubated with geopropolis, 70% ethanol (geopropolis solvent), and carboplatin after 6, 24, 48, and 72 hours. Cell viability was analyzed by the crystal violet method. Geopropolis was efficient against canine OSA cells in a dose- and time-dependent way, leading to a distinct morphology compared to control. Geopropolis cytotoxic action was exclusively due to its constituents since 70% ethanol (its solvent) had no effect on cell viability. Carboplatin had no effect on OSA cells. Geopropolis exerted a cytotoxic effect on canine osteosarcoma, and its introduction as a possible therapeutic agent in vivo could be investigated, providing a new contribution to OSA treatment. © 2013 Naiara Costa Cinegaglia et al.

Glândula hipofaríngeas na vespa social Polistes versicolor (Olivier): da morfologia às relações com o comportamento

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Nutrição de operárias de uruçu-amarela, Melipona flavolineata Friese, 1900 (Apidae: Meliponina)

A criação de abelhas sem ferrão é antiga nas Américas. No entanto, a atividade ainda esta subdesenvolvida, necessitando de melhorias nas técnicas de manejo. Este estudo avaliou alternativas nutricionais para a abelha amazônica Melipona flavolineata, visando substituição da alimentação com mel e pólen fermentado. As seguintes alternativas nutricionais foram comparadas com o mel (T1): xarope de açúcar invertido com minerais (T2) e este xarope acrescido de solução de aminoácidos e vitaminas nas seguintes concentrações: 0,5% (T3), 1,0% (T4) e 10% (T5). Ao pólen fermentado (T1) foram comparados alimentos fermentados com inóculo de pólen fermentado de M. flavolineata, constituídos de: pólen apícola (T2); levedo (T3); e extrato de soja, em duas diferentes concentrações de proteínas (T4, 12% e T5, 18%). O valor nutricional das dietas foi baseado no consumo diário, no peso das operárias, no tamanho dos acinos das glândulas hipofaringeas e no tamanho dos oócitos. Avaliaram-se, tambem, os custos dos ingredientes das dietas. Os resultados obtidos indicaram que dentre as alternativas para o mel, não houve diferenças estatísticas entre o controle e todos os tratamentos. Foram encontradas diferenças apenas entre os tamanhos dos acinos das operárias alimentadas com os tratamentos 2 e 4, sendo o tratamento 4 superior. Os custos dos ingredientes indicaram o tratamento 2 como sendo mais barato que os demais. Dentre as alternativas para o sabura foram encontradas maiores diferenças. O consumo do tratamento 4 foi significativamente superior ao do T3, indicando maior aceitação do extrato de soja em relação ao levedo. Em relação aos demais parâmetros avaliados, o tratamento 5 foi superior a todos os demais e seu custo foi muito inferior ao do T2 e semelhante ao dos T3 e T4. Concluiu-se que as melhores alternativas para a nutrição de M. flavolineata sao o xarope de acucar invertido com minerais, e o pólen fermentado semi-artificial à base de extrato de soja. Colônias recém-formadas, com 500-600 abelhas, devem receber 10 a 20 ml de xarope e 25 g de pólen fermentado semi-artificial semanalmente.

Production of the First Effective Hyperimmune Equine Serum Antivenom against Africanized Bees

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Similarity of heterochromatic regions in the stingless bees (Hymenoptera: Meliponini) revealed by chromosome painting

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O léxico da apicultura e da melinponicultura no Brasil: limites e flexibilidade para sua fixação em um dicionário terminológico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O gênero em questão: crítica e formação nos Bildungsromane The Secret Life of Bees, de Sue Monk Kidd, e Sapato de salto, de Lygia Bojunga

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cladistic analysis of self-grooming indicates a single origin of eusociality in corbiculate bees (Hymenoptera: Apidae)

Behavioural traits have been used extensively in recent years as an important character source for making phylogenetic inferences. The phylogenetic positions of the members of the Apini subtribe are increasingly being debated, and new characters must be examined. We analysed the presence and absence of certain behavioural patterns, as well as the sequences of some of these patterns, to generate 79 characters. Eleven species comprised the ingroup, and Xylocopini comprised the outgroup. Parsimony analysis showed that the most parsimonious tree was (Euglossina(Bombina(Apina+Meliponina))). This topology is consistent with most studies that use morphological data and the few that use behavioural data, which suggests that advanced eusociality arose only once in a common ancestor of the clade Apina plus Meliponina; however, this hypothesis is inconsistent with our molecular data. Thus we considered behavioural, molecular, and morphological data and recovered the same topology, in which eusociality has a single origin in corbiculate bees.

Removal of clay by stingless bees: load size and moisture selection

Some organisms disperse energy, associated with the transportation of resource, which is not necessarily food. Stingless bees of Central Amazonia (Melipona flavolineata and M. lateralis) collect clay in banks along streams for nest building. The moisture of the clay varies along the bank, and bees collect clay from specific location, indicating that there is some sort of preference regarding their selection. This study aims at identifying: if larger bees carry more clay; if there is a preference for moisture of substrates; and if bees are less efficient accumulating and transporting clay when it is wet. In order to do so, I measured the size of the bees and of the pellets of clay found in the corbicula. I set up a field experiment to test substrate preferences. The amount of clay transported, increased exponentially in accordance to the size of the bee, and the preferred substrate was the driest clay. The amount and the efficiency of removal of clay were not affected by the moisture of the substrate. Despite the wet clay being denser, it does not reduce the efficiency of exploitation of the resource, but suggests that bees spend more energy to carry the same quantity of wet clay, which may be the underlying mechanism explaining their preference for removing drier clay.

Acute kidney injury after massive attack of Africanised bees

Acute kidney injury (AKI) is a well-documented complication of massive attack by Africanised bees and can be observed 48-72 h after the accident. We report a case of Africanised bees attack followed by severe and lethal AKI. A 56-year-old man was admitted to emergency department after a massive attack of Africanised bees (>1000 bee stings). He was unconscious, presenting with hypotension and tachycardia. Mechanical ventilation, volume expansion and care for anaphylaxis were instituted. The patient was transferred to the intensive care unit (ICU) and after 48 h he developed rhabdomyolysis, oliguria, increased creatinine levels, hyperkalaemia and refractory acidosis. A diagnosis of AKI secondary to rhabdomyolysis and shock was made. The patient was treated with a prolonged course of haemodialysis. However, he progressed to refractory shock and died 5 days after admission.