Intra-population plasticity of Anopheles darlingi's (Diptera, Culicidae) biting activity patterns in the state of Amapá, Brazil

OBJECTIVE: To assess the variation in Anopheles darlingi's biting activity compared to An. marajoara in the same locality and to biting activity data from other regions. METHODS: Using human bait, eight observations of the biting activity of An. darlingi and An. marajoara were carried out during 1999 and 2000 in the municipality of São Raimundo do Pirativa, state of Amapá, Brazil. Each observation consisted of three consecutive 13-hour collections, close to full moon. There were shifts of collectors in the observation points and nocturnal periods. RESULTS: An. darlingi revealed considerable plasticity of biting activity in contrast to An. marajoara, which showed well-defined crepuscular biting peaks. No significant correlation between density and biting activity was found, but a significant correlation existed between time and proportional crepuscular activity, indicating underlying ecological processes not yet understood. Two of the four available data sets having multiple observations at one locality showed considerable plasticity of this species' biting patterns as well. CONCLUSION: Intra-population variation of biting activity can be as significant as inter-population variation. Some implications in malaria vector control and specific studies are also discussed.

Can climate shape flight activity patterns of Plebeia remota Hymenoptera, Apidae)?

Flight activity of foragers of four colonies of Plebeia remota (Holmberg, 1903) was registered from December 1998 to December 1999, using an automated system (photocells and PLC system). The colonies originated from two different regions: Cunha, state of São Paulo, and Prudentópolis, state of Paraná, Brazil. Flight activity was influenced by different climatic factors in each season. In the summer, the intensity of the correlations between flight activity and climatic factors was smaller than in the other seasons. During the autumn and winter, solar radiation was the factor that most influenced flight activity, while in the spring, this activity was influenced mainly by temperature. Except in the summer, the various climatic factors similarly influenced flight activity of all of the colonies. Flight activity was not affected by geographic origin of the colonies. Information concerning seasonal differences in flight activity of P. remota will be useful for prediction of geographic distribution scenarios under climatic changes.

Atrial natriuretic peptide and feeding activity patterns in rats

This review presents historical data about atrial natriuretic peptide (ANP) from its discovery as an atrial natriuretic factor (ANF) to its role as an atrial natriuretic hormone (ANH). As a hormone, ANP can interact with the hypothalamic-pituitary-adrenal axis (HPA-A) and is related to feeding activity patterns in the rat. Food restriction proved to be an interesting model to investigate this relationship. The role of ANP must be understood within a context of peripheral and central interactions involving different peptides and pathways

Effects of flooding of the River Paraná on the temporal activity of Anopheles (Nyssorhynchus) darlingi Root (Diptera: Culicidae), at the border state of Mato Grosso do Sul and São Paulo, Brazil

INTRODUCTION: Study of the temporal activity of malaria vectors during the implantation of a hydroelectric power station on the River Paraná, intended to generate electrical energy. The river separates the States of São Paulo and Mato Grosso do Sul, in Brazil. The objective was to verify whether alterations occurred in the wealth and diversity indices of Anopheles, following two successive floods, extended to the temporal activity and nycthemeral rhythm followed over a five year period. METHODS: Mosquito capture was performed monthly using the Human Attraction Technique and Shannon Traps. The first, executed for 24h, provided the nycthemeral rhythm and the second, lasting 15h, permitted the tracking of Anopheles during the two floods. RESULTS: The bimodal pattern of Anopheles darlingi defined before these floods was modified throughout the environment interventions. The same effect had repercussions on the populations of An albitarsis s.l., An triannulatus and An galvaoi. Activity prior to twilight was less affected by the environment alterations. CONCLUSIONS: The dam construction provoked changes in Anopheles temporal activity patterns, permitting classification of the area as an ecologically steady and unstable situation. Differences observed in Anopheles behavior due to the capture methods revealed the influence of solo and multiple attractiveness inside the populations studied.

Annual activity of the lizard Liolaemus occipitalis (Squamata, Liolaemidae) in the coastal sand dunes of southern Brazil

The activity pattern of the small sand lizard, Liolaemus occipitalis Boulenger, 1885, was investigated in the coastal sand dunes at Quintão beach (Palmares do Sul, southern, Brazil), between September 1998 and August 1999. The results showed that L. occipitalis is active all along the year, but with variations in its daily and seasonal activity patterns associated to climatic changes in the habitat. Lizard activity pattern was distributed as follows: under the sand, burrowed (73%), under vegetation (14%), dislocation (7%) and basking (6%). Mean habitat temperatures (air and substrate) were significantly different. The results indicate that L. occipitalis is a thigmothermic and heliothermic species that regulates its body temperature through behavioral mechanisms, and that thermoregulation is mainly associated with substrate.

Daily activity and microhabitat use of sympatric lizards from Serra do Cipó, southeastern Brazil

We studied the influence of seasonality on the daily activity pattern and microhabitat use of three sympatric lizard species, Cnemidophorus ocellifer Spix, 1825 (Teiidae), Tropidurus montanus Rodrigues, 1987 and Eurolophosaurus nanuzae (Rodrigues, 1981) (Tropiduridae), in an area of campos rupestres (rocky fields) habitat in state of Minas Gerais, Brazil. Cnemidophorus ocellifer exhibited low density and activity concentrated within the hottest hours of the day, and was observed mainly on shaded rocks. Tropidurus montanus and E. nanuzae had similar activity patterns that did not vary between seasons. Activity of T. montanus was related to environmental temperatures. However, we did not find such relationships for E. nanuzae during the dry season. Both T. montanus and E. nanuzae were sighted mainly on exposed rocks. Extension of activity varied between seasons, shorter for C. ocellifer and longer for T. montanus and E. nanuzae during the rainy season.

The night and day of dung beetles (Coleoptera, Scarabaeidae) in the Serra do Japi, Brazil: elytra colour related to daily activity

In the present study 387 dung beetles (Coleoptera: Scarabaeidae) were surveyed at the Serra do Japi, in the Atlantic Forest in São Paulo State, with four baited pitfall traps during the months of December, 1998, and January, 1999 during eight 24 hour cycles. A total of 30 species were identified and temporal variation in activity patterns among the species shows a specialization in the use of food resources: 9 species were classified as nocturnal and 13 as diurnal. The daily activity pattern of dung beetles does not necessarily correspond to the taxonomic classification, but is strongly related to the colouring of species, determined by predominant elytra colour: nocturnal species have 89 % more chances of being black as opposed to colourful. Black nocturnal species might have evolved as an interspecific adaptation to avoid predation (cryptic colouring). Among the colourful diurnal dung beetles, measure of body length of each species shows that development of bright colouring was more often found in medium to large species, which suggests that colouring evolved as a response to intraspecific pressures, important in agonistic encounters among males.

Evaluation of Insecticide Resistance and Biochemical Mechanisms in a Population of Culex quinquefasciatus (Diptera: Culicidae) from São Paulo, Brazil

To establish an insecticidal resistance surveillance program, Culex quinquefasciatus mosquitoes from São Paulo, Brazil, were colonized (PIN95 strain) and analyzed for levels of resistance. The PIN95 strain showed low levels of resistance to organophosphates [malathion (3.3-fold), fenitrothion (11.2-fold)] and a carbamate [propoxur (3.0-fold)]. We also observed an increase of 7.4 and 9.9 in a and b esterase activities, respectively, when compared with the reference IAL strain. An alteration in the sensitivity of acetylcholinesterase to insecticide inhibition was also found in the PIN95 mosquitoes. The resistant allele (Ace.1R), however, was found at low frequencies (0.12) and does not play an important role in the described insecticide resistance. One year later, Cx. quinquefasciatus mosquitoes were collected (PIN96 strain) at the same site and compared to the PIN95 strain. The esterase activity patterns observed for the PIN96 strain were similar to those of the PIN95 mosquitoes. However the occurrence of the Ace.1R allele was statistically higher in the PIN96 strain. The results show that esterase-based insecticide resistance was established in the PIN95 Cx. quinquefasciatus population and that an acethylcholinesterase based resistant mechanism has been selected for. A continuous monitoring of this phenomenon is fundamental for rational mosquito control and insecticide application programs.

Reducing bumblefoot lesions in a group of captive Magellanic penguins (Spheniscus magellanicus) with the use of environmental enrichment

Captive penguins are prone to pododermatitis (bumblefoot) lesions due to sedentary habits, changes in normal activity patterns, prolonged time on hard and abrasive surfaces, and less time swimming in the water. Environmental enrichment allows the use of creative and ingenious techniques that aim to keep the captive animals occupied by increasing the range and the diversity of behavioral opportunities always respecting the ethological needs of the species. The main goal of this work was to use environmental enrichment techniques to reduce pododermatitis in a group of captive penguins. Five captive Magellanic penguins (Spheniscus magellanicus) that were showing bumblefoot lesions were followed during this project. To monitor the lesions, all animals were physically restraint 3 times a week over a period of 12 weeks. Environmental enrichment was introduced daily in the water with the goal of enhancing their time in the water for one extra hour daily. The results demonstrate that in a twelve weeks period, four animals showed significant reduction of the lesions in both feet and in two animals the lesions were completely healed. With these results we can conclude that aquatic environmental enrichment allowed this group of penguins to spend more time in the water, favoring the reduction of the bumblefoot lesions.

Anurans of the Serra do Caraça, southeastern Brazil: species composition and phenological patterns of calling activity

Annual patterns of calling and breeding activity of 38 anuran species were studied at Serra do Caraça, an 11,233 ha reserve located in a contact zone between Cerrado and Atlantic forest at the southern Espinhaço range, southeastern Brazil. Five patterns were evident: (1) species that call year-round or nearly year-round with larger aggregations generally observed in the rainy months, (2) species with opportunistic calling activity associated with rainfall during the wettest months of the year, (3) winter species, (4) explosive breeders with intense calling activity triggered by heavy rains during the rainy season or only in the beginning of the rainy season, and (5) summer species with variable breeding seasons. Both the monthly number of species with calling males and the monthly number of species that showed the maximum class of calling males were positively correlated with both mean monthly temperature and monthly precipitation.

Use of accelerometry to measure physical activity in adults and the elderly

OBJECTIVE: To review the use of accelerometry as an objective measure of physical activity in adults and elderly people. METHODS: A systematic review of studies on the use of accelerometty as an objective measure to assess physical activity in adults were examined in PubMed Central, Web of Knowledge, EBSCO and Medline databases from March 29 to April 15, 2010. The following keywords were used: "accelerometry," "accelerometer," "physical activity," "PA," "patterns," "levels," "adults," "older adults," and "elderly," either alone or in combination using "AND" or "OR." The reference lists of the articles retrieved were examined to capture any other potentially relevant article. Of 899 studies initially identified, only 18 were fully reviewed, and their outcome measures abstracted and analyzed. RESULTS: Eleven studies were conducted in North America (United States), five in Europe, one in Africa (Cameroon) and one in Australia. Very few enrolled older people, and only one study reported the season or time of year when data was collected. The articles selected had different methods, analyses, and results, which prevented comparison between studies. CONCLUSIONS: There is a need to standardize study methods for data reporting to allow comparisons of results across studies and monitor changes in populations. These data can help design more adequate strategies for monitoring and promotion of physical activity.

Long term follow-up and patterns of response of ALT in patients with chronic hepatitis NANB/C treated with recombinant interferon-alpha

The response to interferon treatment in chronic hepatitis NANB/C has usually been classified as complete, partial or absent, according to the behavior of serum alanine aminotransferase (ALT). However, a more detailed observation of the enzymatic activity has shown that the patterns may be more complex. The aim of this study was to describe the long term follow-up and patterns of ALT response in patients with chronic hepatitis NANB/C treated with recombinant interferon-alpha. A follow-up of 6 months or more after interferon-a was achieved in 44 patients. We have classified the serum ALT responses into six patterns and the observed frequencies were as follows: I. Long term response = 9 (20.5%); II. Normalization followed by persistent relapse after IFN = 7 (15.9%); III. Normalization with transient relapse = 5 (11.9%); IV. Temporary normalization and relapse during IFN = 4 (9.1%); V. Partial response (more than 50% of ALT decrease) = 7 (15.9%); VI. No response = 12 (27.3%). In conclusion, ALT patterns vary widely during and after IFN treatment and can be classified in at least 6 types.

Spatial distribution and esterase activity in populations of Aedes (Stegomyia) aegypti (Linnaeus) (Diptera: Culicidae) resistant to temephos

INTRODUCTION:The need for studies that describe the resistance patterns in populations of Aedes aegypti (Linnaeus) in function of their region of origin justified this research, which aimed to characterize the resistance to temephos and to obtain information on esterase activity in populations of Aedes aegypticollected in municipalities of the State of Paraíba.METHODS:Resistance to temephos was evaluated and characterized from the diagnostic dose of 0.352mg i.a./L and multiple concentrations that caused mortalities between 5% and 99%. Electrophoresis of isoenzymes was used to verify the patterns of esterase activity among populations of the vector.RESULTS:All populations of Aedes aegypti were resistant to temephos, presenting a resistance rate (RR) greater than 20. The greatest lethal dose 50% of the sample (CL50) was found for the municipality of Lagoa Seca, approximately forty-one times the value of CL50 for the Rockefeller population. The populations characterized as resistant showed two to six regions of α and β-esterase, called EST-1 to EST-6, while the susceptible population was only seen in one region of activity.CONCLUSIONS:Aedes aegyptiis widely distributed and shows a high degree of resistance to temephos in all municipalities studied. In all cases, esterases are involved in the metabolism and, consequently, in the resistance to temephos.

Gastric myoelectrical activity in neonates of different gestational ages by means of electrogastrography

PURPOSE: to describe the patterns of the gastric myoelectrical activity, pre-and postprandially, in clinically stable neonates of different gestational ages, during their first two weeks of life by means of Electrogastrography. PATIENTS AND METHODS: Electrogastrography was recorded in forty-five clinically stable neonates of different gestational ages (group I: 15 neonates of > 37 weeks, group II: 15 premature neonates of 32-37 weeks; Group III: 15 premature neonates of 28-31 weeks) receiving intermittent enteral feedings during their first two weeks of life. Electrogastrography recordings were performed for 1 hour pre-and postprandially. The Electrogastrography signal was recorded using the portable MicroDigitrapper Electrogastrography recording device and after motion artifacts were deleted, the remaining Electrogastrography data were submitted to quantitative analysis based on the "Running Spectrum Analysis". RESULTS: The percentages of normogastria, pre-and postprandially were greater than the percentages of gastric dysrythmias in all three studied groups. Furthermore, all neonates had the mean values of the Electrogastrography dominant frequency predominantly within the normogastria range, in both periods analyzed. There were no significant differences in the relative change of the Electrogastrography dominant power among the groups. CONCLUSION: This study demonstrates that the Electrogastrography patterns are similar between premature and full term neonates during the pre-and postprandial periods. The results of this study also indicate that the gastric myoelectrical activity in premature and full term neonates is immature, as compared to that described for older neonates, children and adults.

Characterization and biological activity of a brazilian isolate of Bacillus sphaericus (Neide) highly toxic to mosquito larvae

Primary powders of Bacillus sphaericus strain S2 isolated from soil samples in Brazil, and strain 2362 were produced in a 14 liter fermentor. Growth patterns and sporulation observed in three trials with strains S2 and 2362 in the fermentor were similar. Second-instar larvae of Culex quinquefasciatus, Anopheles albimanus, Anopheles quadrimaculatus, and Aedes aegypti exposed for 48 hr to strain S2 responded with LC50 values of 0.25, 5.95, 12.28 and 140.0 ppb of lyophilized primary powder, respectively. Under the same conditions, strain 2362 resulted in LC50 values of 0.39, 7.16, 16.93 and 307.0 ppb of lyophilized primary powder, respectively, in those mosquito larvae. Statistical analysis of the bioassay data did not show significant differences among LC50 values observed in B. sphaericus strains S2 and 2362, at the 0.05 level. Toxins of strains S2 and 2362 were extracted at pH 12 with NaOH. Electrophoresis of the extracts in polyacrylamide gel under denaturing conditions revealed the 51 and 42 kDa toxins in both S2 and 2362 B. sphaericus strains. The presence of the 42 kDa peptide in the extracts was confirmed by Western blot and Elisa, with anti-42 kDa IgG previously prepared from strain 2362.