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There is no suitable vaccine against human visceral leishmaniasis (VL) and available drugs are toxic and/or present high cost. In this context, diagnostic tools should be improved for clinical management and epidemiological evaluation of disease. However, the variable sensitivity and/or specificity of the used antigens are limitations, showing the necessity to identify new molecules to be tested in a more sensitive and specific serology. In the present study, an immunoproteomics approach was performed in Leishmania infantum promastigotes and amastigotes employing sera samples from VL patients. Aiming to avoid undesired cross-reactivity in the serological assays, sera from Chagas disease patients and healthy subjects living in the endemic region of disease were also used in immunoblottings. The most reactive spots for VL samples were selected, and 29 and 21 proteins were identified in the promastigote and amastigote extracts, respectively. Two of them, endonuclease III and GTP-binding protein, were cloned, expressed, purified and tested in ELISA experiments against a large serological panel, and results showed high sensitivity and specificity values for the diagnosis of disease. In conclusion, the identified proteins could be considered in future studies as candidate antigens for the serodiagnosis of human VL.
The ability of “comfort-food” (CF) diet to revert long-term effects of early-life stress (ELS) is less well known. The objective of this study was to verify if the chronic exposure to CF diet in animals submitted to ELS could relief the stress response at behavioral, neuroendocrine, and neurobiochemical levels, via differences in glucocorticoid receptors expression in brain areas involved in the stress response. From the second day of life, litters of Wistar rats and their mothers were submitted to the reduced nesting material protocol (ELS). In adult life, ELS and a control group were exposed chronically to two diet schemes: standard rat chow only or both “CF” diet, containing fat (34%) and sugar (20%) and a diet similar to the standard diet. Anxiety-like behavior, neuroendocrine response stress, leptin, GR, SOCS-3, pSTAT3, and the abdominal fat were evaluated. The anxiety-like behavior results showed that ELS group when exposed to comfort food were not different from the others groups. Chronic exposure to CF diet induced an anxiety-like behavior in the control group. Groups chronically exposed to CF diet had lower levels of corticosterone over time independent of the neonatal group. The ELS group exposed to the “CF” diet had higher levels of hippocampal GR, lower levels of hypothalamic SOCS-3 and greater accumulation of abdominal fat. Chronic CF diet consumption is able to reduce corticosterone levels independent of the neonatal history, but is associated with anxiety-like behavior in animals without previous history of trauma. Metabolic disturbances like increased adiposity and altered SOCS-3 seem to be a result of multiple insults (neonatal trauma followed by chronic CF diet). We highlight that the Control-chow and ELS-chow data were previously published, and are included in this study for comparative analysis.
Recent open-label trials show that psychedelics, such as ayahuasca, hold promise as fast-onset antidepressants in treatment-resistant depression.
To test the antidepressant effects of ayahuasca, we conducted a parallel-arm, double-blind randomized placebo-controlled trial in 29 patients with treatment-resistant depression. Patients received a single dose of either ayahuasca or placebo. We assessed changes in depression severity with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Depression Rating scale at baseline, and at 1 (D1), 2 (D2), and 7 (D7) days after dosing.
We observed significant antidepressant effects of ayahuasca when compared with placebo at all-time points. MADRS scores were significantly lower in the ayahuasca group compared with placebo at D1 and D2 (p = 0.04), and at D7 (p < 0.0001). Between-group effect sizes increased from D1 to D7 (D1: Cohen's d = 0.84; D2: Cohen's d = 0.84; D7: Cohen's d = 1.49). Response rates were high for both groups at D1 and D2, and significantly higher in the ayahuasca group at D7 (64% v. 27%; p = 0.04). Remission rate showed a trend toward significance at D7 (36% v. 7%, p = 0.054).
To our knowledge, this is the first controlled trial to test a psychedelic substance in treatment-resistant depression. Overall, this study brings new evidence supporting the safety and therapeutic value of ayahuasca, dosed within an appropriate setting, to help treat depression. This study is registered at http://clinicaltrials.gov (NCT02914769).
Habitat modification may facilitate the emergence of novel pathogens, and the expansion of agricultural frontiers make domestic animals important sources of pathogen spillover to wild animals. We demonstrate for the first time that Plasmodium juxtanucleare, a widespread parasite from domestic chickens, naturally infects free-living passerines. We sampled 68 wild birds within and at the border of conservation units in central Brazil composed by Cerrado, a highly threatened biome. Seven out of 10 passerines captured in the limits of a protected area with a small farm were infected by P. juxtanucleare as was confirmed by sequencing a fragment of the parasite's cytochrome b. Blood smears from these positive passerines presented trophozoites, meronts and gametocytes compatible with P. juxtanucleare, meaning these birds are competent hosts for this parasite. After these intriguing results, we sampled 30 backyard chickens managed at the area where P. juxtanucleare-infected passerines were captured, revealing one chicken infected by the same parasite lineage. We sequenced the almost complete mitochondrial genome from all positive passerines, revealing that Brazilian and Asian parasites are closely related. P. juxtanucleare can be lethal to non-domestic hosts under captive and rehabilitation conditions, suggesting that this novel spillover may pose a real threat to wild birds.
Ultrasound technology provides a oportunity to quickly and economically estimate carcass atributes on the live animal (Brethour, 2000). In general, this technology has been used to detect variation for fat depth and ribeye area (longissimus dorsi muscle) in performance tested yearling bulls at several countries. In the present study, real time ultrasonography was used to predict the ribeye area (RA) and the subcutaneous fat thickness (FT) in Nellore crossbred.
This study assessed the incidence and risk factors for dengue virus (DENV) infection among children in a prospective birth cohort conducted in the city of Recife, a hyperendemic dengue area in Northeast Brazil. Healthy pregnant women (n = 415) residing in Recife who agreed to have their children followed were enrolled. Children were followed during their first 24 months of age (May/2011–June/2014), before the 2015 Zika virus outbreak. DENV infection was detected by reverse-transcriptase polymerase chain reaction and/or serology (anti-DENV IgM/IgG). The incidence rates per 1000 person-years (py) and its association with risk factors by age bands (0–12, >12–30 months) were estimated through Poisson regression models. Forty-nine dengue infections were detected; none progressed to severe forms. The incidence rates were 107·6/1000py (95% CI 76·8–150·6) and 93·3/1000py (95% CI 56·1–154·4) in the first and second years of age, respectively. Male children (risk ratios (RR) = 2·33; 95% CI 1·09–4·98) and those born to DENV-naïve mothers (RR = 2·42; 95% CI 1·01–5·80) were at greater risk of infection in the first year of age. In the second year, children born to Caucasian/Asian descent skin colour mothers had a threefold higher risk of infection (RR = 3·34; 95% CI: 1·08–10·33). These data show the high exposure of children to DENV infection in our setting and highlight the role of biological factors in this population's susceptibility to infection.
Field trials were conducted in 2013 and 2014 to investigate the tolerance of limpograss to increasing rates of hexazinone. Dose-response curves were generated using linear and quadratic regression models to determine the hexazinone estimated dose (ED) required to provide 10% (ED10) and 20% (ED20) of visual injury and herbage mass reduction. The ED10 and ED20 for visual estimates of injury were estimated to be 0.05 and 0.14 kg ai ha-1 at 60 d after treatment (DAT). Regarding forage herbage mass reduction, the ED10 and ED20 were estimated to be 0.07 and 0.19 kg ai ha-1 in 2013, whereas in 2014, the ED10 and ED20 were estimated to be 0.03 and 0.06 kg ai ha-1, respectively. The significant difference in herbage mass reduction between 2013 and 2014 was likely due to rainfall patterns, which possibly promoted hexazinone leaching in 2013 and consequently, less activity. Overall, hexazinone resulted in high degrees of limpograss injury across all response variables in both years; therefore, smutgrass control in limpograss pastures with hexazinone may not be a viable option. The presence or absence of smutgrass should be considered before limpograss establishment as there is no viable herbicide to selectively remove smutgrass from limpograss swards.
Plants’ ability to rebuild their tiller population is affected by weather changes and management strategies. The hypothesis of the present study was that frequency and severity of defoliation alter Mulato grass (Brachiaria ruziziensis × Brachiaria brizantha cv. Marandu) sward development, and the proportion of aerial and basal tillers, interfering with sward stability. The objective was to evaluate aerial, basal and total tiller population density and changes in tillering dynamics. Treatments corresponded to strategies of rotational grazing characterized by combinations between two pre-grazing (95% and maximum canopy light interception during regrowth; LI95% and LIMax) and two post-grazing conditions (15 and 20 cm stubble height). The experimental period comprised four seasons of the year: summer 2008 (February–March 2008); autumn–early spring (April to mid-November 2008); late spring (mid-November–December 2008); and summer 2009 (January–March 2009). Density of aerial tillers decreased from summer 2008 to late spring. Tiller death decreased from summer 2008 to autumn–early spring. Aerial and total tiller death increased from late spring to summer 2009, mainly for the LI95% treatment. No differences were observed in the tiller population stability index of aerial tillers for LI treatments or post-grazing heights. The balance between tiller appearance and death for basal tillers remained relatively stable from summer 2008 to late spring. For aerial tillers the balance decreased to negative values from summer 2008 to autumn–early spring for both LI treatments. For total tiller population, the balance decreased to negative values from summer 2008 to autumn–early spring. Results indicated a strong seasonal effect on Mulato grass tillering and growth. Tillering dynamics were affected primarily by grazing frequency, which changed the relative importance of basal and aerial tillers. The results suggested that basal tillering was the predominant perennation pathway.
Upside-down jellyfish (genus Cassiopea) can be found in tropical coastal waters worldwide. Until now reports of the genus from Brazilian waters have been scant. We report here medusae and scyphistomae collected from Cabo Frio, Rio de Janeiro state. Although we could not unambiguously identify the material using morphological criteria, genetic sequence data (COI) indicate that the Brazilian jellyfishes are genetically similar to those from Bermuda, Hawaii and Florida, which are related to specimens from the Red Sea (Cassiopea andromeda). We hypothesize that the presence of C. andromeda in Brazil is due to an invasion event, as the scyphistomae were found growing over the known invasive ascidian Styela plicata. Estimation of divergence time between Brazil (Cabo Frio) and Florida/Bermuda populations is that it occurred at the beginning of ship movement to South America.
Fruits of Melastomataceae constitute a key resource for Neotropical frugivores. However, the mechanisms determining gut-passage effects on seed germination are poorly known. Here, we determine how bird gut-passage affects seed germination in three species of Miconieae by running germination experiments, examining changes in seed coat structure and determining germination inhibition by fruit extracts. Mature fruits of Clidemia urceolata, Leandra aurea and Miconia rubiginosa were sampled in south-eastern Brazil and seeds were submitted to treatments evaluating gut-passage effects and different concentrations of fruit extracts. Light and scanning electron microscopy were used to compare seed coat structure and thickness of control and gut-passed seeds. We found minor effects of gut passage on seed germination. However, changes in seed coat structure of gut-passed seeds of L. aurea may have been related to a decrease in germination. Our data also support the idea that germination inhibitors in fruit pulp may contribute to the inhibition effect. Our study corroborates the idea that changes in the seed coat following gut passage modulate the complex fruit–frugivore interactions, especially between plants and generalist dispersers, and that seed cleaning is a key factor determining seedling establishment in Neotropical Melastomataceae.
After 22 yr of the low-level liquid scintillation counting 14C laboratory at the Center for Nuclear Energy in Agriculture (CENA) at São Paulo University (USP), Piracicaba, Brazil, and several collaborative projects with Brazilian and international researchers from distinct scientific areas, the first 14C accelerator mass spectrometry (AMS) laboratory in Latin America was installed at the Physics Institute of the Universidade Federal Fluminense (UFF), Niterói, Brazil. A 250kV single stage accelerator produced by National Electrostatics Corporation began its operation in 2012. In this work, we compare measurements performed at the AMS Radiocarbon Laboratory at UFF (LAC-UFF) with those performed at CENA and the University of Georgia (UGAMS), Georgia, USA. All the results obtained from distinct inorganic and organic samples were in very good agreement.
The aim of this study was to analyze the economic viability of producing dairy goat kids fed liquid diets in alternative of goat milk and slaughtered at two different ages. Forty-eight male newborn Saanen and Alpine kids were selected and allocated to four groups using a completely randomized factorial design: goat milk (GM), cow milk (CM), commercial milk replacer (CMR) and fermented cow colostrum (FC). Each group was then divided into two groups: slaughter at 60 and 90 days of age. The animals received Tifton hay and concentrate ad libitum. The values of total costs of liquid and solid feed plus labor, income and average gross margin were calculated. The data were then analyzed using the Monte Carlo techniques with the @Risk 5.5 software, with 1000 iterations of the variables being studied through the model. The kids fed GM and CMR generated negative profitability values when slaughtered at 60 days (US$ −16.4 and US$ −2.17, respectively) and also at 90 days (US$ −30.8 and US$ −0.18, respectively). The risk analysis showed that there is a 98% probability that profitability would be negative when GM is used. In this regard, CM and FC presented low risk when the kids were slaughtered at 60 days (8.5% and 21.2%, respectively) and an even lower risk when animals were slaughtered at 90 days (5.2% and 3.8%, respectively). The kids fed CM and slaughtered at 90 days presented the highest average gross income (US$ 67.88) and also average gross margin (US$ 18.43/animal). For the 60-day rearing regime to be economically viable, the CMR cost should not exceed 11.47% of the animal-selling price. This implies that the replacer cannot cost more than US$ 0.39 and 0.43/kg for the 60- and 90-day feeding regimes, respectively. The sensitivity analysis showed that the variables with the greatest impact on the final model’s results were animal selling price, liquid diet cost, final weight at slaughter and labor. In conclusion, the production of male dairy goat kids can be economically viable when the kids diet consists mainly of either cow milk or fermented colostrum, especially when kids are slaughtered at 90 days of age.
Determining the phylogenetic and biogeographic distribution of physical dormancy remains a major challenge in germination ecology. Here, our goal was to describe a novel water-impermeable seed coat mechanism causing physical dormancy (PY) in the seeds of Chaetostoma armatum (Melastomataceae). Although seed coat permeability tests indicated a significant increase in seed weight after soaking in distilled water, anatomical and dye-tracking analyses showed that both water and dyes penetrated the seed coat but not the embryo, which remained in a dry state. The water and dye penetrated the lumen of the exotestal cells, which have a thin outer periclinal face and thickened secondary walls with U-shaped phenolic compounds. Because of this structure, water and dye do not penetrate the inner periclinal face of the exotestal cells, indicating PY. Puncturing the seeds increased germination more than tenfold compared to that of the control, but GA3 did not increase germination further. A significant fraction of the seeds did not germinate after puncturing, indicating that embryos are also physiologically dormant (PD). This paper constitutes the first report of the water-impermeable seed coat in the Myrtales and the first report of physiophysical (PD+PY) dormancy in a shrub from a tropical montane area.
Vinasse and biochar are by-products of biofuel production that can be used as sources of nutrients to crops or soil amendments to improve soil quality. Despite the recent interest in biochar and vinasse effects on soil properties, little is known about their effect on weed communities. We hypothesized that the addition of biochar and vinasse to the soil could affect weed seed germination and growth, and that different weed species would show different responses to these soil amendments. Therefore, the objectives of this study were to determine the effects of vinasse and biochar on the germination and growth of Palmer amaranth, sicklepod, and southern crabgrass. The study was conducted under laboratory and growth chamber conditions. Treatments consisted of four levels of vinasse (0, 10, 20, and 40 L m−2) and biochar (0, 0.5, 2.5, and 12.5 kg m−2) applied to a sandy loam soil. Biochar at 0.5 and 2.5 kg m−2 increased germination of Palmer amaranth but had no effect on sicklepod and southern crabgrass. Vinasse reduced germination of all species. However, sicklepod germination was less affected by vinasse at 10 and 20 L m−2 than the other two species. Vinasse at 40 L m−2 decreased Palmer amaranth, southern crabgrass and sicklepod germination 57, 26 and 87%, respectively. Biochar had no consistent effect on the vegetative growth of the species studied. Vinasse at 10 L m−2 stimulated growth of sicklepod and southern crabgrass compared to the nontreated control. Our results suggested that vinasse used as a soil amendment could affect weed community structure by decreasing germination of susceptible species, but plants and weed species that can get established in vinasse amended soils might show higher growth rates.
Epigenetic studies suggest that diseases that develop in adulthood are related to certain conditions to which the individual is exposed during the initial stages of life. Experimental evidence has demonstrated that offspring born to mothers maintained on high-Na diets during pregnancy have higher mean arterial pressure (MAP) in adulthood. Although these studies have demonstrated the importance of prenatal phases to hypertension development, no evidence regarding the role of high Na intake during postnatal phases in the development of this pathology has been reported. Therefore, in the present study, the effects of Na overload during childhood on induced water and Na intakes and on cardiovascular parameters in adulthood were evaluated. Experiments were carried out in two groups of 21-d-old rats: experimental group, maintained on hypertonic saline (0·3 m-NaCl) solution and food for 60 d, and control group, maintained on tap water and food. Later, both groups were given water and food for 15 d (recovery period). After the recovery period, chronic cannulation of the right femoral artery was performed in unanaesthetised rats to record baseline MAP and heart rate (HR). The experimental group was found to have increased basal MAP (98·6 (sem 2·6) v. 118·3 (sem 2·7) mmHg, P< 0·05) and HR (365·4 (sem 12·2) v. 398·2 (sem 7·5) beats per min, P< 0·05). There was a decrease in the baroreflex index in the experimental group when compared with that in the control group. A water and Na intake test was performed using furosemide. Na depletion was found to induce an increase in Na intake in both the control and experimental groups (12·1 (sem 0·6) ml and 7·8 (sem 1·1), respectively, P< 0·05); however, this increase was of lower magnitude in the experimental group. These results demonstrate that postnatal Na overload alters behavioural and cardiovascular regulation in adulthood.
The silvopastoral system (SPS) has been suggested to ensure sustainability in animal production systems in tropical ecosystems. The objective of this study was to evaluate pasture characteristics, herbage intake, grazing activity and milk yield of Holstein×Zebu cows managed in two grazing systems (treatments): SPS dominated by a graminaceous forage (Brachiaria decumbens) intercropped with different leguminous herbaceous forages (Stylosanthes spp., Pueraria phaseoloides and Calopogonium mucunoides) and legume trees (Acacia mangium, Gliricidia sepium and Leucaena leucocephala), and open pasture (OP) of B. decumbens intercropped only with Stylosanthes spp. Pastures were managed according to the rules for organic cattle production. The study was carried out by following a switch back format with 12 cows, 6 for each treatment, over 3 experimental years. Herbage mass was similar (P>0.05) for both treatments, supporting an average stocking rate of 1.23 AU/ha. Daily dry matter intake did not vary (P>0.05) between treatments (average of 11.3±1.02 kg/cow per day, corresponding to 2.23±0.2% BW). Milk yield was higher (P<0.05; 10.4±0.06 kg/cow per day) in the SPS than in the OP (9.5±0.06 kg/cow per day) during the 1st year, but did not significantly differ (P>0.05) in subsequent years. The highest (P<0.05) values for herbage mass and milk yield were observed during the 3rd year. In the SPS, with moderate shade (19% shade relative to a full-sun condition), the grass CP was higher (P<0.05) than in the OP, although the NDF content and digestibility coefficient were not modified. The animals spent more time (P<0.05) idling in the SPS than in OP. The higher legume proportion in the SPS was associated with the higher CP level in B. decumbens relative to the OP, which could explain the better (P<0.05) performance of the cows in silvopastoral areas during the 1st year. However, during the 2nd and 3rd years, similarities in the legume percentages of both systems resulted in similar (P>0.05) milk yields. Low persistence of Stylosanthes guianensis was observed over the experimental period, indicating that the persistence of forage legumes under grazing could be improved using adapted cultivars that have higher annual seed production. The SPS and a diversified botanical composition of the pasture using legume species mixed with grasses are recommended for organic milk production.
Lear’s Macaw Anodorhynchus leari is currently listed as “Endangered” by IUCN. Although it only breeds on cliffs at two protected sites in Bahia State, Brazil, there is no accurate information on population parameters such as the number of breeding pairs and their breeding performance. Between 2009 and 2010, we sought to quantify, for the first time, breeding population size and the main breeding parameters for the species in the two known breeding sites, by quantifying the number of active nests and monitoring 75 breeding attempts. Overall, 80% of the breeding attempts were successful with 1.33 (± 0.86 SD) fledglings/breeding attempt (productivity) and 1.67 (± 0.60 SD) fledglings/successful nest (brood size). Breeding success and productivity were higher in 2010, while brood size did not vary between years and breeding sites. By adding 73 estimated nests to the 41 nests monitored, 228 individuals were estimated to be reproductively active in 2010, representing c.20% of the population (1,125 individuals). Given that the species is confined to a single population, further population increases could provoke overcrowding and negative density-dependent effects if it does not expand geographically. Therefore, long-term population monitoring focusing on the fraction of the population that is actually breeding and its breeding performance, rather than solely on the whole population size, is important for a better understanding of the population dynamics and conservation of this species.
This paper studies the risk of ship collision off the coast of Portugal based on Automatic Identification System (AIS) data, which is recorded and maintained by the Portuguese coastal Vessel Traffic Service (VTS) control centre (CCTMC). Computer programs for decoding, visualization and analysis of the AIS data have been developed. From analysis of the AIS data available, maritime traffic off the coast of Portugal is characterized and a statistical analysis of traffic in the Traffic Separation Schemes is provided. An algorithm has been developed to assess the risk profile and the relative importance of routes associated with ports. A method is proposed to calculate the collision risk from the assessment of the number of collision candidates by estimating future distances between ships based on their previous positions, courses and speeds, and comparing those distances with a defined collision diameter. Values of causation probability suggested in several studies are used to calculate the expected number of collisions in the period of time under investigation based on the number of collision candidates. The results of this study are then compared with the number of collisions that have occurred between 1997–2006, registered and maintained by the Portuguese Maritime Authority.
Rheumatoid arthritis (RA) is a chronic inflammatory disease that mainly targets the synovial membrane, cartilage and bone. It affects 1 % of the population and is associated with significant morbidity and increased mortality. Se is an essential trace element with antioxidant properties and the ability to modulate the immune responses. Selemax® is an inactive yeast (Saccharomyces cerevisiae) enriched with organic Se. The aim of the present study was to investigate the effects of Selemax® administration in models of an antigen-induced arthritis (AIA) in C57BL/6 mice, and of an adjuvant-induced arthritis (AdIA) in Holtzman rats. As control, the animals were treated with the same inactivated yeast species that was not enriched for Se. In the AIA model, treatment with different doses of Selemax® (0·01, 0·1, 1 and 10 % added to food) significantly decreased the number of inflammatory cells recruited to the knee cavity, essentially by reducing the number of neutrophils. Levels of proinflammatory cytokines, including TNF-α, IL-1β and chemokine (C-X-C motif) ligand 1/keratinocyte chemoattractant (CXCL1/KC), were also reduced in the peri-articular tissue of mice treated with Selemax® at the tested dose (1 %). In the AdIA model in rats, Selemax® treatment decreased paw oedema and hypernociception. This reduction was associated with inhibition of the influx of proinflammatory cells. Therefore, treatment with Selemax® is associated with amelioration of several inflammatory and functional parameters in models of arthritis, suggesting that this Se-enriched yeast should be evaluated further in patients with RA.