Simultaneous circulation of all four dengue serotypes in Manaus, State of Amazonas, Brazil in 2011

INTRODUCTION: Manaus, the capital city of the state of Amazon with nearly 2 million inhabitants, is located in the middle of the Amazon rain forest and has suffered dengue outbreaks since 1998. METHODS: In this study, blood samples were investigated using reverse transcriptase-polymerase chain reaction (RT-PCR), aimed at identifying dengue virus serotypes. RESULTS: Acute phase sera from 432 patients were tested for the presence of dengue virus. Out of the 432 patients, 137 (31.3%) were found to be positive. All the four dengue virus serotypes were observed. CONCLUSIONS: The simultaneous circulation of the four dengue serotypes is described for the first time in Manaus and in Brazil.

Laboratory estimation of the effects of increasing temperatures on the duration of gonotrophic cycle of Anopheles albimanus (Diptera: Culicidae)

The increase of malaria transmission in the Pacific Coast of Colombia during the occurrence of El Niño warm event has been found not to be linked to increases in the density of the vector Anopheles albimanus, but to other temperature-sensitive variables such as longevity, duration of the gonotrophic cycle or the sporogonic period of Plasmodium. The present study estimated the effects of temperature on duration of the gonotrophic cycle and on maturation of the ovaries of An. albimanus. Blood fed adult mosquitoes were exposed to temperatures of 24, 27, and 30°C, held individually in oviposition cages and assessed at 12 h intervals. At 24, 27, and 30°C the mean development time of the oocytes was 91.2 h (95% C.I.: 86.5-96), 66.2 h (61.5-70.8), and 73.1 h (64-82.3), respectively. The mean duration of the gonotrophic cycle for these three temperatures was 88.4 h (81.88-94.9), 75 h (71.4-78.7), and 69.1 h (64.6-73.6) respectively. These findings indicate that both parameters in An. albimanus are reduced when temperatures rose from 24 to 30°C, in a nonlinear manner. According to these results the increase in malaria transmission during El Niño in Colombia could be associated with a shortening of the gonotrophic cycle in malaria vectors, which could enhance the frequency of man-vector contact, affecting the incidence of the disease.

A RT-PCR method for selective amplification and phenotypic characterization of all three serotypes of Sabin-related polioviruses from viral mixtures

Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.

Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia

The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.

Evaluation of winter temperatures on apple budbreak using grafted twigs

Temperature is the main climate factor related to induction, maintenance and dormancy release in apple (Malus domestica Borkh.). The inadequate chilling exposure in apples causes budbreak problems, resulting in decrease in yield potential. Thus, the knowledge of physiological principles and environmental factors determining the dormancy phenomenon, especially winter temperature effects, it is necessary for the efficient selection of cultivars in a productive region. In addition, it is indispensable to adapt the orchard management aiming to decrease the problems caused by lack chilling during winter. The objective of this study was to evaluate the influence of different thermal conditions during the dormancy period on budbreak of apple cultivars. One-year-old twigs of 'Castel Gala' and 'Royal Gala' cultivars, grafted on M7 rootstock, were submitted to temperatures of 5, 10 and 15ºC for different exposure periods (168; 336; 672; 1,008 and 1,344 hours). After treatments execution, the plants were kept in a greenhouse at 25ºC. Budbreak was quantified when accumulated 3,444; 6,888; 10,332; 13,776; 17,220 and 20,664 GDHºC after temperature treatments. The cultivars responded differently to temperature effect during the winter period. The temperature of 15ºC during winter shows a greater effectiveness on 'Castel Gala' apple budbreak while in the 'Royal Gala' apples the temperatures of 5 and 10ºC show better performance. 'Castel Gala' cultivar (low chilling requirement) may supply its physiological necessities, may be capable to budburst, even when subjected to higher temperatures in relation to 'Royal Gala' apples (high chilling requirement).

Effect of all-trans retinoic acid on newly diagnosed acute promyelocytic leukemia patients: results of a Brazilian center

Thirty-seven patients with acute promyelocytic leukemia (APL) were treated with all-trans retinoic acid (ATRA). Patients received 45 mg m-2 day-1 po of ATRA until complete remission (CR) was achieved, defined as: a) presence of less than 5% blasts in the bone marrow, with b) white blood cells >103/mm3, c) platelets >105/mm3 and d) hemoglobin concentration >8 g/dl, with no blood or platelet transfusions. Thirty-one (83.7%) patients achieved CR by day 50, and 75% of these before day 30. Correction of the coagulopathy, achieved between days 2 and 10 (mean, 3 days), was the first evidence of response to treatment. Only one patient had been previously treated with chemotherapy and three had the microgranular variant M3 form. Dryness of skin and mucosae was the most common side effect observed in 82% of the patients. Thrombosis, hepatotoxicity and retinoid acid syndrome (RAS) were observed in 7 (19%), 6 (16%) and 4 (11%) patients, respectively. Thirteen (35%) patients had to be submitted to chemotherapy due to hyperleukocytosis (above 40 x 103/mm3) and six of these presented with new signs of coagulopathy after chemotherapy. Four (11%) patients died secondarily to intracerebral hemorrhage (IH) and two (5.4%) dropped out of the protocol due to severe ATRA side effects (one RAS and one hepatotoxicity). RAS and IH were related strictly to hyperleukocytosis. The reduced use of platelets and fresh frozen plasma probably lowered the total cost of treatment. We conclude that ATRA is an effective agent for inducing complete remission in APL patients.

Cold storage of peaches cv. Aurora grown in the Zona da Mata Mineira, Minas Gerais State, Brazil

This study aimed to evaluate the postharvest behavior of peach cv. Aurora 1 harvested in the Zona da Mata region of Minas Gerais in two ripening stages and kept under different storage temperatures. Fruits on mid-ripe and fully ripe stages were stored at three temperatures: 5.6 ± 1.57 °C and 72.8 ± 3.8% RH; 10.4 ± 0.5 °C and 95.8 ± 5.5% RH; 21.04 ± 1.63 °C and 96.9 ± 2.6% RH up to 28 storage days (SD) . During storage, fruits stored at 21.04 ± 1.63 °C were evaluated every two days until 8 SD, and every four days for fruits stored at other temperatures. The harvest day was assigned as day zero. The variables evaluated were CO2 production, color of the pericarp and pulp, fresh mass loss, flesh firmness, total soluble solids, titratable acidity, contents of ascorbic acid and carotenoids. The fresh mass loss increased during storage, peaking at 5.6 °C. The reduction in ascorbic acid content was higher in fully ripe fruits at all temperatures. Mid-ripe fruits reached the end of the storage period with better quality. The temperature of 10.4 °C was the most efficient in keeping postharvest quality of peach cv. Aurora 1 harvested in the Zona da Mata region.

Effects of light and temperature on isoprene emission at different leaf developmental stages of eschweilera coriacea in central Amazon

Isoprene emission from plants accounts for about one third of annual global volatile organic compound emissions. The largest source of isoprene for the global atmosphere is the Amazon Basin. This study aimed to identify and quantify the isoprene emission and photosynthesis at different levels of light intensity and leaf temperature, in three phenological phases (young mature leaf, old mature leaf and senescent leaf) of Eschweilera coriacea (Matamatá verdadeira), the species with the widest distribution in the central Amazon. In situ photosynthesis and isoprene emission measurements showed that young mature leaf had the highest rates at all light intensities and leaf temperatures. Additionally, it was observed that isoprene emission capacity (Es) changed considerably over different leaf ages. This suggests that aging leads to a reduction of both leaf photosynthetic activity and isoprene production and emission. The algorithm of Guenther et al. (1999) provided good fits to the data when incident light was varied, however differences among E S of all leaf ages influenced on quantic yield predicted by model. When leaf temperature was varied, algorithm prediction was not satisfactory for temperature higher than ~40 °C; this could be because our data did not show isoprene temperature optimum up to 45 °C. Our results are consistent with the hypothesis of the isoprene functional role in protecting plants from high temperatures and highlight the need to include leaf phenology effects in isoprene emission models.

Ecology of colonizing populations of the figfly Zaprionus indianus (Diptera, Drosophilidae) in Porto Alegre, Southern Brazil

Ecological parameters such as trophic niche overlap and niche breadth were computed from the frequency of all drosophilid species collected in 2001 and 2002, in the urban area of Porto Alegre city, Brazil. Independently of place, drosophilids community composition and components breeding or feeding sites, the highest frequencies of Zaprionus indianus (Gupta, 1970) were obtained during seasons with higher average temperatures, especially during summer. From a total of the 19,146 individuals of Z. indianus sampled, 80% were found in this season. The data of trophic niche breadth suggest a higher opportunism of adult flies in feeding substrate use, but the females are still selective in oviposition substrate choice. For the values of niche overlap, only for some species, did we find any correlation between these and species richness and/or number of resources, and the most of the correlation values considering breeding and feeding sites were positive. The colonization of Z. indianus in Porto Alegre could be leading to adjustments in the survival strategies of the resident species, but it is possible that many species have conditions for coexisting with the invader.

Bromeliad-associated mosquitoes from Atlantic forest in Santa Catarina Island, southern Brazil (Diptera, Culicidae), with new records for the State of Santa Catarina

Bromeliad-associated mosquitoes (Diptera: Culicidae) in Atlantic Forest in Florianópolis, Santa Catarina, southern Brazil, were studied, examining plants of Vriesea philippocoburgi Wawra and Aechmea lindenii (E. Morren) Baker var. lindenii at secondary Atlantic rain forest, and A. lindenii and Vriesea friburgensis Mez var. paludosa (L. B. Smith) at "restinga" per month, during 12 months. No immature forms of mosquitoes were collected from A. lindenii in the secondary forest. Collections obtained 368 immature mosquitoes, none of them from A. lindenii from rain forest. Culex (Microculex) spp. constituted 79.8% of the total, Wyeomyia (Phoniomyia) spp. 17.93%, and Anopheles (Kerteszia) cruzii (Dyar & Knab, 1908) only 1.36%. The study shows the great predominance of species of medical importance not yet proved, and the small number of immature stages of anopheline mosquitoes. The rainfall, but not the mean temperatures, significantly influenced the quantity of mosquitoes from V. philippocoburgi. Significant differences between the quantities of immature forms of all the bromeliad species were found, and the shape of the plants could be important to the abundance of mosquitoes. All six species of Cx. (Microculex) found are recorded for the first time in the State of Santa Catarina, and all six species of Wyeomyia (Phoniomyia) are recorded for the first time in bromeliads in this state.

Consumption of Cinara spp. (Hemiptera, Aphididae) by Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae)

Adults and larvae of coccinellids were observed feeding on populations of the giant conifer aphids Cinara spp. on Pinus spp., in Southern Brazil. The objective of this research is to evaluate the consumption capacity of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) on these aphid species, in order to obtain information for biological control programs. Ten larvae of each predator species were fed with aphids of small size (nymphs of 1st and 2nd instars), and 10 with aphids of medium size (nymphs of 3rd and 4th instars), maintained under 15ºC, 20ºC and 25ºC, 12 h photophase and 70 ± 10% relative humidity. The aphids were counted every 24 hours, replacing those that were consumed. The total consumption of Cinara by the larvae of C. sanguinea was not statistically different at the three temperatures: 325.5; 322.2 and 324.8 of small aphids and 121.3; 140.4 and 109.9 of medium ones, respectively at 15ºC, 20ºC and 25ºC. The consumption by H. convergens was higher than by C. sanguinea and increased noticeably with temperature: 444 aphids at 15ºC; 491.3 at 20ºC and 513.3 at 25ºC, considering the small aphids, and 187.1; 205.1 and 216.6 of medium aphids at the three temperatures. The small aphids weigh about half as much as medium ones and were preferred by all larval instars probably because they are easier to manipulate than the large ones. Both predators, especially the 4th instar larvae, showed high consumption capacity on the Cinara nymphs at all temperatures and can be regarded as promising biological control agents.

Solution thermodynamics of methocarbamol in some ethanol + water mixtures

Apparent thermodynamic functions, Gibbs energy, enthalpy and entropy of solution and mixing, for methocarbamol in ethanol + water mixtures, were evaluated from solubility data determined at temperatures from 293.15 K to 313.15 K and from calorimetric values of drug fusion. The drug solubility was greatest in the mixtures with 0.70 or 0.80 mass fraction of ethanol and lowest in neat water across all temperatures studied. Non-linear enthalpy-entropy compensation was found for the dissolution processes. Accordingly, solution enthalpy drives the respective processes in almost all the solvent systems analyzed.

Rheological behavior of mixed drink of annona and milk

In this study the rheological behavior in different temperatures (0; 6; 18 e 24 ºC) and physicochemical parameters of integral annona (Annona squamosa) pulp and the annona pulp with milk in different percentages pulp/milk (75g of annona pulp/25g of milk, 50g of annona pulp/50g of milk, 25g of annona pulp/75g of milk) have been availed, in order to verify the effect of temperature and pulp concentration in the rheological behavior of these beverages. To obtain the rheological parameters a concentric cylinder rheometer has been used and the rheograms were analyzed using the Ostwald-de-Wael (power Law) and Herschel-Bulkley models. The physicochemical parameters (sugars, pH, ash, acidity and soluble solids) were determined in order to establish correlations with the rheological behavior. Finally, the best results had been obtained using the Herschel-Bulkley model; the low values for the behavior index (n <1) obtained confirm the pseudoplastic behavior of all samples.

Influence of seed size and ecological factors on the germination and emergence of field bindweed (Convolvulus arvensis)

An understanding of seed germination ecology of weeds can assist in predicting their potential distribution and developing effective management strategies. Influence of environmental factors and seed size on germination and seedling emergence of Convolvulus arvensis (field bindweed) was studied in laboratory and greenhouse conditions. Germination occurred over a wide range of constant temperatures, between 15 and 40 ºC, with optimum germination between 20 and 25 ºC. Time to start germination, time to 50% germination and mean germination time increased while germination percentage and germination index decreased with an increase in temperature from 20 ºC, salinity and osmotic stress. However, germination was tolerant to low salt (25 mM) or osmotic stress (0.2 MPa), but as salinity and osmotic stress increased, germination percentage and germination index decreased. Seeds of C. arvensis placed at soil surface showed maximum emergence and decreased as seeding depth increased. Seeds of C. arvensis germinated over a wide range of pH (4 to 9) but optimum germination occurred at pH 6 to 8. Under highly alkaline and acidic pH, time to start germination, time to 50% germination and mean germination time increased while germination percentage and germination index decreased. Increase in field capacity caused decreased time to start germination, time to 50% germination and mean germination time but increased germination percentage and germination index. Bigger seeds had low time to start germination, time to 50% germination and mean germination time but high germination percentage and germination index. Smaller seeds were more sensitive to environmental factors as compared to larger or medium seeds. It can be concluded that except for pH, all environmental factors and seed sizes adversely affect C. arvensis as regards seed germination or emergence and germination or emergence traits, and larger seeds result in improved stand establishment and faster germination than small seeds, regardless of moisture stress or deeper seeding depth.

Effect of light and temperature on germination and early growth of Vochysia tucanorum Mart., Vochysiaceae, in cerrado and forest soil under different radiation levels

Vochysia tucanorum Mart. (Vochysiaceae) is a very widely distributed species in the cerrado and forests in Brazil, from the State of Bahia to Paraná. Its seed germination was analysed under eight treatments using different conditions of light and temperature. Up to 73 days, at least ca. 93% of the seeds germinated in all treatments, except under alternating temperatures of 35°/10°C (62%). Light enhanced germination, except under constant temperature of 25°C when seeds are not photoblastic. At this temperature, the highest percentage of germination was found. Initial vegetative growth was analysed by comparing the effects of shading, by means of different percentages of full daylight (100%, 45%, 10.6%, 4.8%), and soils from cerrado and forest. During 123 days, no mortality was recorded and cotyledons persisted on the seedlings of all treatments. In general, the seedlings of V. tucanorum were found to be more or less indifferent to the soil from cerrado or forest and shading seems to promote height increment. However, total dry mass was larger under a radiation of 45% full daylight and smaller under extreme conditions (100% or 4.8% full daylight).