BACKGROUND The coronaviruses (CoVs) called the attention of the world for causing outbreaks of severe acute respiratory syndrome (SARS-CoV), in Asia in 2002-03, and respiratory disease in the Middle East (MERS-CoV), in 2012. In December 2019, yet again a new coronavirus (SARS-CoV-2) first identified in Wuhan, China, was associated with a severe respiratory infection, known today as COVID-19. This new virus quickly spread throughout China and 30 additional countries. As result, the World Health Organization (WHO) elevated the status of the COVID-19 outbreak from emergency of international concern to pandemic on March 11, 2020. The impact of COVID-19 on public health and economy fueled a worldwide race to approve therapeutic and prophylactic agents, but so far, there are no specific antiviral drugs or vaccines available. In current scenario, the development of in vitro systems for viral mass production and for testing antiviral and vaccine candidates proves to be an urgent matter. OBJECTIVE The objective of this paper is study the biology of SARS-CoV-2 in Vero-E6 cells at the ultrastructural level. METHODS In this study, we documented, by transmission electron microscopy and real-time reverse transcription polymerase chain reaction (RT-PCR), the infection of Vero-E6 cells with SARS-CoV-2 samples isolated from Brazilian patients. FINDINGS The infected cells presented cytopathic effects and SARS-CoV-2 particles were observed attached to the cell surface and inside cytoplasmic vesicles. The entry of the virus into cells occurred through the endocytic pathway or by fusion of the viral envelope with the cell membrane. Assembled nucleocapsids were verified inside rough endoplasmic reticulum cisterns (RER). Viral maturation seemed to occur by budding of viral particles from the RER into smooth membrane vesicles. MAIN CONCLUSIONS Therefore, the susceptibility of Vero-E6 cells to SARS-CoV-2 infection and the viral pathway inside the cells were demonstrated by ultrastructural analysis.
Abstract: Honey pollen samples of Melipona seminigra pernigraMoure & Kerr 1950 sampled between 2017 and 2019 from experimental apiaries installed in campo rupestre on canga (CRC) vegetation of the Serra dos Carajás aimed to evaluated seasonal floral availability of undisturbed and mining-influenced areas. Around one hundred pollen types were identified mainly belonging to Fabaceae, Myrtaceae and Euphorbiaceae (31, 6 and 5 species, respectively). Mining area presented the highest pollen richness, almost twice those identified in the undisturbed areas. 80% of the pollen types are rare with concentrations ≤ 2,000 pollen grains/10 g, while the remaining were the most abundant, frequent and the primary bee sources. These latter correspond mostly to native plants species such as Tapirira guianensis Aubl., Protium spp., Aparisthmium cordatum (A.Juss.) Baill., Mimosa acutistipula var. ferrea Barneby, Periandra mediterranea (Vell.) Taub., Miconia spp., Pleroma carajasense K.Rocha, Myrcia splendens (Sw.) DC., Serjania spp. and Solanum crinitum Lam. All pollen types were identified during both seasons, but higher concentration values are related to the dry period (June-September). The statistical analysis of the pollen data indicated that there was no significant difference between undisturbed and mining-influenced areas, since primary bee sources of this study are widespread used in revegetation of mined areas.
Resumo: O conteúdo polínico de amostras de mel coletadas nos anos de 2017 e 2019 de apiários experimentais de Melipona seminigra pernigraMoure & Kerr 1950, instalado dentro de uma vegetação de campo rupestre em um afloramento de canga na Serra dos Carajás, sudeste da Amazônia, foi analisado para entender a variabilidade local dos recursos florais em áreas naturais e perturbadas. Aproximadamente 100% dos tipos polínicos foram identificados e pertencem principalmente às famílias Fabaceae, Myrtaceae e Euphorbiaceae (31, 6 e 5 espécies, respectivamente). Áreas de mineração apresentaram a maior riqueza de pólen, quase o dobro daquelas identificadas em áreas perturbadas. 80% dos tipos de pólen são raros com concentrações ≤ 2.000 grãos de pólen/10g, enquanto que os restantes foram os mais abundantes, frequentes e fontes primárias para as abelhas. Este últimos correspondem principalmente a plantas nativas como Tapirira guianensis Aubl., Protium spp., Aparisthmium cordatum (A.Juss.) Baill., Mimosa acutistipula var. ferrea Barneby, Periandra mediterrânea (Vell.) Taub., Miconia spp., Pleroma carajasense K.Rocha, Myrcia splendens (Sw.) DC., Serjania spp. e Solanum crinitum Lam. Todos os tipos polínicos foram identificados durante ambas as estações, mas altas concentrações estão relacionadas ao período seco (junho-setembro). A análise estatística indicou que não houve diferença significativa nos dados de pólen de mel entre áreas naturais e áreas anteriormente degradadas, uma vez que as fontes primárias das abelhas deste estudo são amplamente utilizadas na revegetação de áreas mineradas.
BACKGROUND The impact of arbovirus cocirculation in Brazil is unknown. Dengue virus (DENV) reinfection may result in more intense viraemia or immunopathology, leading to more severe disease. The Zika virus (ZIKV) epidemic in the Americas provided pathogenicity evidence that had not been previously observed in flavivirus infections. In contrast to other flaviviruses, electron microscopy studies have shown that ZIKV may replicate in viroplasm-like structures. Flaviviruses produce an ensemble of structurally different virions, collectively contributing to tissue tropism and virus dissemination. OBJECTIVES AND METHODS In this work, the Aedes albopictus mosquito cell lineage (C6/36 cells) and kidney epithelial cells from African green monkeys (Vero cells) were infected with samples of the main circulating arboviruses in Brazil [DENV-1, DENV-2, DENV-3, DENV-4, ZIKV, Yellow Fever virus (YFV) and Chikungunya virus (CHIKV)], and ultrastructural studies by transmission electron microscopy were performed. FINDINGS We observed that ZIKV, the DENV serotypes, YFV and CHIKV particles are spherical. ZIKV, DENV-1, -2, -3 and -4 presented diameters of 40-50 nm, and CHIKV presented approximate diameters of 50-60 nm. Viroplasm-like structures was observed in ZIKV replication cycle. MAIN CONCLUSIONS The morphogenesis of these arboviruses is similar to what has been presented in previous studies. However, we understand that further studies are needed to investigate the relationship between viroplasm-like structures and ZIKV replication dynamics.
ABSTRACT The aim of this work was to identify and describe the morphology of non-pollen microfossils present in the sediments of a core collected near the Lagoa Comprida barrier, Rio de Janeiro State, Brazil. Eight forms of fungi, two types of Chlorococcales algae at the colonial stage, one zygospore of Zygnematales, four of diatoms, one of microforaminifer, two cysts of dinoflagellates, one spicule of Porifera, one spore of bryophyte, and nine spores of ferns and lycophytes were identified. Ecological information on the organisms of origin was given to provide reference material for paleoenvironmental reconstruction along the Holocene in restinga areas.
RESUMO O trabalho teve como objetivo identificar e descrever a morfologia de microfósseis não polínicos ocorrentes nos sedimentos de um testemunho retirado próximo à barra da Lagoa Comprida, Estado do Rio de Janeiro, Brasil. Foram identificadas oito formas de fungos, dois tipos de algas Chlorococcales em estágio colonial, um tipo de zygósporo de alga Zygnematales, quatro de diatomáceas, um de microforaminífero, dois de cistos de dinoflagelados, um de microesclera de Porifera, um de esporo de briófita e nove de esporos de samambaias e licófitas. Informações ecológicas sobre os organismos de origem foram fornecidas para prover material de referência para a reconstrução paleoambiental ao longo do Holoceno em áreas de restinga.
The lack of an experimental animal model for the study of dengue pathogenesis is a limiting factor for the development of vaccines and drugs. In previous studies, our group demonstrated the susceptibility of BALB/c mice to infection by dengue virus (DENV) 1 and 2, and the virus was successfully isolated in several organs. In this study, BALB/c mice were experimentally infected intravenously with DENV-4, and samples of their saliva were collected. Viral RNA extracted from the saliva samples was subjected to qRT-PCR, with a detection limit of 0.002 PFU/mL. The presence of DENV-4 viral RNA was detected in the saliva of two mice, presenting viral titers of 109 RNA/mL. The detection of DENV RNA via saliva sampling is not a common practice in dengue diagnosis, due to the lower detection rates in human patients. However, the results observed in this study seem to indicate that, as in humans, detection rates of DENV RNA in mouse saliva are also low, correlating the infection in both cases. This study reports the first DENV detection in the saliva of BALB/c immunocompetent mice experimentally infected with non-neuroadapted DENV-4.
Zika virus (ZIKV) has infected thousands of Brazilian people and spread to other American countries since 2015. The introduction of ZIKV brought a strong impact to public health in Brazil. It is of utmost importance to identify a susceptible cell line that will enable the isolation and identification of the virus from patient samples, viral mass production, and testing of drug and vaccine candidates. Besides real-time reverse transcriptase polymerase chain reaction diagnosis for detecting the viral genome, virus isolation in cell lines was useful in order to study the structure of the viral particle and its behaviour inside cells. Analysis of ZIKV infected cell lines was achieved using transmission electron microscopy (TEM). Blood was obtained from a Brazilian patient during the first days after presenting with signs of the disease, and ZIKV from the patient’s blood was isolated in the C6/36 mosquito cell line. Afterwards, Vero cells were inoculated with the viral suspension, fixed six days after inoculation, embedded in polymers, and ultra-thin cut. Like dengue viruses, this flavivirus showed numerous virus particles present inside cellular vesicles thereby confirming the susceptibility of the Vero cell line to ZIKV replication. TEM is a unique technique available to make the virus visible.
In cell culture, cell structures suffer strong impact due to centrifugation during processing for electron microscope observation. In order to minimise this effect, a new protocol was successfully developed. Using conventional reagents and equipments, it took over one week, but cell compression was reduced to none or the lowest deformation possible.
Abstract Pollen is used in the human diet as a food supplement because of its high nutritional value; however, this product is prone to fungal contamination that could potentially generate toxins that are harmful to human health. This study aimed to verify the floral diversity of commercial brands of bee pollen and their mycotoxicological safety for human consumption. A total of 27 bee pollen samples were analyzed; these samples represented commercial brands, either showing an inspection seal or not, marketed in the State of Rio de Janeiro. The analyzed parameters included floral diversity through palynological analysis, water activity, fungal counts, identification and toxigenic profiles. The palynological analysis identified nine plant families, of which the Asteraceae was predominant. Analysis of hygienic quality based on fungal load showed that 92% of samples were reproved according to the commercial, sanitary, and food safety quality indicators. Aspergillus, Cladosporium and Penicillium were the most common genera. Toxigenic evaluation showed that 25% of the A. flavus strains produced aflatoxins. The high rate of contamination of products bearing an inspection seal emphasizes the need to monitor the entire procedure of bee pollen production, as well as to revise the current legislation to ensure safe commercialization of this product.
Propolis is a resinous substance collected by bees from many parts of plants and mixed with wax, pollen and salivary secretions. Its composition is complex and closely related to the vegetation features of each region. Thirty-three propolis samples were collected from four Brazilian regions (Northeast, Southeast, South and Central-West) and had their antioxidant activity analyzed by the connected oxidation of b-carotene/linoleic acid. A significant variation was observed for the antioxidant activity (51.33-92.70%), according to the region where the sample was collected. The antioxidant activity of propolis samples collected in the Northeast region was lower than those collected in the Central-West, South and Southeast regions, respectively.
A própolis é uma substância resinosa coletada de diversas partes das plantas por abelhas e misturada à cera, pólen e secreções salivares. Sua composição é complexa e está relacionada, principalmente, às características da vegetação de cada região. Trinta e três amostras de própolis foram coletadas em quatro regiões brasileiras (Nordeste, Sudeste, Sul e Centro-Oeste) e analisadas quanto à sua capacidade antioxidante, pela oxidação acoplada do sistema β-caroteno/ácido linoleico. Variação significativa na capacidade antioxidante (51,33-92,70%) foi observada de acordo com a região onde a amostra foi coletada. A capacidade antioxidante das amostras de própolis da região Nordeste foi menor que a das amostras das regiões Centro-Oeste, Sul e Sudeste, respectivamente.
Tropical Vochysiaceae includes mainly trees, and also shrubs and subshrubs. Three genera and seven species are present in the Brazilian state of Santa Catarina. The pollen morphology of six species of trees, belonging to three genera of the Vochysiaceae A. St-Hil. family, was studied. Herbaria samples were obtained, processed and treated by standard methods. The pollen grain morphology of Callisthene, Qualea and Vochysia is distinct. Medium sized pollen grains occur in Vochysia species, and small ones in Callisthene and Qualea. Specific characteristics were considered at species level [C. castellanosii H. F. Martins, C. kuhlmannii H. F.Martins, Qualea cordata Spreng var. cordata, Q. cryptantha (Spreng) Warm. var. cryptantha, Vochysia magnifica Warm. and V. tucanorum Mart.]. The presence of a fastigium (vestibulum) and a thin space devoid of nexine fixing the boundary of the apertural area is characteristic of Qualea and Vochysia species only. Rev. Biol. Trop. 62 (3): 1209-1215. Epub 2014 September 01.
Las Vochysiaceae tropicales incluyen principalmente árboles, arbustos y subarbustos. Tres géneros y siete especies están presentes en el estado brasileño de Santa Catarina. La morfología del polen de las seis especies de árboles, pertenecientes a tres géneros de la Vochysiaceae A. St.- Hil . familia, fue considerado en el presente trabajo. La morfología de los granos de polen de Callisthene Mart., Qualea Aubl. y Vochysia (Aubl.) Juss. es distinta. Los granos de polen de tamaño medio se producen en las especies de Vochysia y pequeños en Callisthene y Qualea. Características particulares fueron considerados a nivel de especie [C. castellanosii H.F. Martins, C. kuhlmannii H.F. Martins, Qualea cordata Spreng var. cordata, Q. cryptantha (Spreng) Warm. var. cryptantha, Vochysia magnifica Warm. and V. tucanorum Mart.]. La presencia de un fastigium (vestibulum) y de un espacio delgado que carece de nexina limita la zona apertural y es característica solo de las especies de Qualea y Vochysia.
Fourier transform infrared attenuated total reflectance (FT-IR ATR) spectroscopy was used to determine 14 different measurands in northeast Brazilian honey samples. Nine different honey samples (six monofloral and three polyfloral) from 2009 obtained from the company CEARAPI underwent FT-IR ATR, palynological, color, and sensorial analysis to obtain preliminary results for these types of honey. The results showed that there are five monofloral, three bifloral, and one extrafloral honey, and also that mid-infrared spectrometry can be used as a screening method for the routine analysis of Brazilian honey, with the advantages of being rapid, nondestructive, and accurate.
In recent years the use of pathogenic microorganisms in acts of bioterrorism has been the subject of major concern in many countries. This paper presents a possible application of viruses and bacteria for warfare and terrorist purposes, as well as a laboratory diagnosis to identify those agents. The viruses of smallpox (orthopoxvirus), of hemorrhagic fever and those belonging to filovirus have been highlighted, inter alia, as agents of human infection with bioterrorist intent. Among the bacteria, the emphasis has been on anthrax (Bacillus anthracis), the plague (Yersinia pestis), botulism (Clostridium botulinum) and tularemia (Francisella tularensis), not to mention ricin (Ricinus communis), as one of the Group B agents.
O uso de microrganismos patogênicos em atos de bioterrorismo é já há algum tempo objeto de grande preocupação em vários países. O presente trabalho apresenta a possível aplicação de vírus e bactérias para fins bélicos e terroristas, bem como o diagnóstico laboratorial para a identificação desses agentes. Foram salientados, entre outros, como agentes de infecções humanas visando o bioterrorismo, os vírus da varíola (ortopoxvírus), os de febres hemorrágicas e os pertencentes aos filovírus. Entre as bactérias foram destacadas as do antrax ( Bacillus anthracis ), da peste ( Yersinia pestis ), do botulismo ( Clostridium botulinum ) e da tularemia ( Francisella tularensis ), incluindo ainda a ricina ( Ricinus communis ) como componente do grupo B de agentes.
The stingless bees are important flowers visitors of several plant species, due to their feeding habits and foraging behavior, constituting an important group to maintain biodiversity and the dynamics of tropical communities. Among stingless bees, Tetragonisca angustula is widely distributed in tropical habitats, and has been considered an important pollinator of different plant families. To support a rational economic use of this group, there is a need to characterize the plant species that represent important sources as part of their diet, as preferred, alternative or casual food sources. The aim of this survey was to distinguish the plant species that T. angustula visited most often. The study was undertaken in four regions of the Atlantic Rainforest in Rio de Janeiro state (Brazil) over a year from March 2008 to February 2009. For this, we collected bees, flowering plants and bee pollen loads from the four sites, and evaluated pollen morphology in the laboratory. Field observations showed the presence of plants belonging to ten different families and pollen loads showed the presence of pollen types belonging to 26 plant families. There were strong differences between pollen types, especially regarding pollen grain shape. The present survey suggests a high value of these plant species as trophic resources for the T. angustula in the understory of Atlantic Rainforest. Changes in these fragments of this forest may compromise the availability of resources for Tetragonisca angustula species and other stingless bees.
Para apoyar el uso racional de las abejas sin aguijón, es necesario conocer las especies de plantas que actúan como fuentes de recursos para estas abejas en su ambiente natural. El objetivo de este estudio fue identificar las especies de plantas que fueron visitadas con mayor frecuencia por abejas Tetragonisca angustula y describir los granos de polen de estas plantas. El estudio se realizó en la Mata Atlántica, donde se recogieron las abejas, las plantas con flores y el polen de las cargas corbiculares de las abejas obreras. La observación de campo mostró la presencia de plantas pertenecientes a diez familias y las cargas de polen mostraron la presencia de tipos de polen pertenecientes a 26 familias botánicas. Hubo grandes diferencias entre los tipos de polen, sobre todo teniendo en cuenta la ornamentación de los granos de polen. Este estudio sugiere un alto valor de estas especies de plantas como recursos tróficos para las abejas jataí en el sub-bosque de la Mata Atlántica. Las alteraciones de los fragmentos de bosque pueden afectar la disponibilidad de recursos para Tetragonisca angustula y otras abejas sin aguijón y ser un gran obstáculo para la su crianza sostenible.
As a result of the institution of the International Geophysical Year in 1957, the Brazilian Navy organized an expedition to the island of Trindade, on which Rudolf Barth participated. He was a researcher at the Oswaldo Cruz Institute and the Naval Research Institute, and a member of the Brazilian Academy of Sciences and the National Research Council. The scientist returned to the island of Trindade the following year, on a second expedition with the Brazilian Navy. The research findings then resulted in some scientific publications and two unpublished reports with observations and data concerning terrestrial, zoological, meteorological, climatological, geomorphological and biological phenomena. The reports are then transcribed.
Em consequência da instituição do Ano Geofísico Internacional, em 1957, a Marinha do Brasil organizou uma expedição à ilha da Trindade, da qual participou Rudolf Barth, pesquisador do Instituto Oswaldo Cruz e do Instituto de Pesquisas da Marinha, membro da Academia Brasileira de Ciências e do Conselho Nacional de Pesquisas. Esse cientista retornou à ilha da Trindade no ano seguinte, em uma segunda viagem com a Marinha brasileira. As pesquisas feitas então resultaram em algumas publicações científicas e em dois relatórios inéditos com observações e dados concernentes a fenômenos zoológicos (terrestres), meteorológicos, climatológicos, geomorfológicos e biológicos. Os relatórios são transcritos a seguir.
Diversas especies de abejas sin aguijón producen miel de botija en Venezuela, la cual no está incluida en las normas venezolanas de calidad. Una de estas especies, la Meli po na favosa, vive en la Península de Paraguaná, donde se conoce como erica o maba. A fin de conocer las mieles de M. favosa, se realizó la determinación de su origen botánico, su caracterización físicoquímica según los métodos de la norma COVENIN 2136-84 para miel de abejas y contenido de nitrógeno por microkjeldahl, y de actividad biológica con métodos espectrofotométricos y de concentración inhibitoria mínima, en seis mieles. Son mieles claras de color ámbar entre 18 y 79 mm Pfund. La composición físicoquímica varió así: acidez libre 12,72-95,86 meq/kg, pH 3,53-4,44, humedad 25,40-32,00 g agua/100 g, 0,01-0.16 g ce ni zas/100g, 10,48-57,55 mgN/100 g, 62,60-69,50 g azúcares reductores/100 g, 0,60-5,10 g sacarosa aparente/100 g, flavonoides 0,10-8,15 mgEQ/100g miel, y polifenoles 51,50-217,19 mgEAG/100 g. La actividad antibac teriana (g miel/100 mL medio de cultivo) fue mayor contra E. coli (12.50-50,00) que contra S. aureus (50,00- 50,00). La actividad antioxidante se ubicó en un rango bajo a alto para mieles, con 45,91-227,92 mmoles equivalentes de Trolox/100 g. El análisis melisopalinológico indicó polen dominante del género Portulaca y la especie Carica papaya.
Diverse species of stingless bees produce por honey in Venezuela,which is not included in the Venezuelan regulations of honey quality. One of these species , the Melipona favosa, lives in the Paraguaná Peninsula, where it is known as erica or maba. In order to know the honeys of M. favosa, the botanical origin was determined, their physicochemical characterization was done according to the methods of the norm COVENIN 2136-84 for honey, the nitrogen content by microkjeldahl, and biological activity by spectrophotometric and minimum inhibitory concentration methods, in six ho neys. They are light honey amber color between 18 and 79 mm Pfund. The physicochemical composition varied as follows: free acidity 12.72- 95.86 meq/kg, pH 3.53-4.44, moisture 25.40-32.00 g water/100 g, 0.01-0.16 g ash/100g, 10.48-57.55 mgN/100 g, 62.60-69.50 g reducing su gars/100 g, 0.60-5.10 g apparent sucrose/100 g, flavonoids 0.10-8.15 mgQE/100g honey, and polyphenols 51.50-217.19 mgGAE/100 g. The antibacterial ac tivity (g ho ney/100 mLculture media) was higher against E. coli (12.50-50.00) than S. aureus (50.00-50.00). The antioxidant activity was in a low to high range for honeys, with 45.91- 227.92 mmoles Trolox equivalents/100 g.