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Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
A growing number of infectious pathogens are spreading among geographic regions. Some pathogens that were previously not considered to pose a general threat to human health have emerged at regional and global scales, such as Zika and Ebola Virus Disease. Other pathogens, such as yellow fever virus, were previously thought to be under control but have recently re-emerged, causing new challenges to public health organisations. A wide array of new modelling techniques, aided by increased computing capabilities, novel diagnostic tools, and the increased speed and availability of genomic sequencing allow researchers to identify new pathogens more rapidly, assess the likelihood of geographic spread, and quantify the speed of human-to-human transmission. Despite some initial successes in predicting the spread of acute viral infections, the practicalities and sustainability of such approaches will need to be evaluated in the context of public health responses.
Objectives: Careful characterization of how functional decline co-evolves with cognitive decline in older adults has yet to be well described. Most models of neurodegenerative disease postulate that cognitive decline predates and potentially leads to declines in everyday functional abilities; however, there is mounting evidence that subtle decline in instrumental activities of daily living (IADLs) may be detectable in older individuals who are still cognitively normal. Methods: The present study examines how the relationship between change in cognition and change in IADLs are best characterized among older adults who participated in the ACTIVE trial. Neuropsychological and IADL data were analyzed for 2802 older adults who were cognitively normal at study baseline and followed for up to 10 years. Results: Findings demonstrate that subtle, self-perceived difficulties in performing IADLs preceded and predicted subsequent declines on cognitive tests of memory, reasoning, and speed of processing. Conclusions: Findings are consistent with a growing body of literature suggesting that subjective changes in everyday abilities can be associated with more precipitous decline on objective cognitive measures and the development of mild cognitive impairment and dementia. (JINS, 2018, 24, 104–112)
In this work we explore the radiocarbon (14C) signal as an independent tool to assess the year of formation of individual tree rings of tropical species in northern Brazil. Three different species were analyzed in this work: Dipteryx magnifica, Enterolobium maximum, and Hymenolobium petraeum. The studied samples are from the stem of only one individual of each species, all cut down in 2008 in Porto Trombetas, Pará, Brazil. Individual tree rings were identified based on wood anatomy and they were counted from bark to pith. Several rings were selected for 14C analysis in order to cover the overall shape of the 14C atmospheric bomb peak (after 1955). The 14C content was measured at Laboratory of Radiocarbon, Universidade Federal Fluminense (LAC-UFF). Results are compared with the Southern Hemisphere 14C atmospheric calibration curves. For E. maximum and H. petraeum the 14C signal exhibits an overall good match with the SH zone 3 and suggests annual seasonality in the growth-ring formation. These species offer suitable characteristics for dendrochronology. The D. magnifica shows mismatches in the 14C measurements that are likely a result of difficulties in identifying ring boundaries with certainty. Additional techniques may be helpful to disentangle the origin of this discrepancy.
N-3 polyunsaturated fatty acids (PUFAs) have been hypothesised to be protective for depression during pregnancy. However, there are few data and no consensus regarding this association. In this line, we aim to evaluate if the concentration of n-3 and n-6 PUFAs, and their ratio, are associated with depressive symptoms throughout pregnancy.
A prospective cohort of 172 Brazilian women was followed at 5–13th, 20–26th and 30–36th weeks of gestation. The presence of depressive symptoms was evaluated using the Edinburgh Postnatal Depression Scale (EPDS) at each pregnancy trimester. Depression was defined as an EPDS score ≥11. The concentrations of n-3 [α-linolenic acid; eicosapentaenoic acid (EPA); docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA)] and n-6 PUFAs [linoleic acid; γ linolenic acid; eicosadienoic acid; eicosatrienoic acid; arachidonic acid; docosatetraenoic acid and docosapentaenoic acid] were expressed as absolute (μg/ml) values. The total n-6/n-3 ratio was calculated. Statistical analyses were performed using univariate and adjusted random intercept logistic model for each fatty acid (FA) considering the longitudinal nature of data. Covariates were selected as potential confounders based on their biological plausibility of having an association with the concentration of FA and depressive symptoms during pregnancy.
The prevalence of depressive symptoms was high in all pregnancy trimesters (1st = 33.7%; 2nd = 18.9%; 3rd = 17.4%). We did not find differences in means FA concentrations by depressive symptom classification, for each follow-up visit. The women presented a 5% decrease in the odds of having depressive symptoms for each one-week increase in the gestational age. As individual women progressed through pregnancy, higher concentrations of EPA (odds ratio (OR) = 0.92; 95% CI: 0.86–0.99), DHA (OR = 0.96; 95% CI: 0.93–0.99), DPA (OR = 0.87; 95% CI: 0.77–0.99) and total n-3 (OR = 0.98; 95% CI: 0.96–0.99) were associated with a lower odds of depressive symptoms, while higher total n-6/n-3 ratio were associated with greater odds of depressive symptoms (OR = 1.40; 95% CI: 1.09–1.79). We detected a decrease in the probability of depressive symptoms as concentrations of total n-3 FA, α-linolenic acid, DPA, and DHA increased. We also observed a sharper decline for women with initial greater chance of depressive symptoms compared with those with lower chance of having these symptoms.
We found a high prevalence of depressive symptoms in low-income Brazilian pregnant women and no significant associations between n-6 FA and depressive symptoms. Lower serum concentrations of DHA, EPA and DPA and a higher n-6/n-3 ratio at each pregnancy trimester were associated with higher odds of depressive symptoms throughout pregnancy.
We propose a theory of weakly nonlinear multidimensional self-sustained detonations based on asymptotic analysis of the reactive compressible Navier–Stokes equations. We show that these equations can be reduced to a model consisting of a forced unsteady small-disturbance transonic equation and a rate equation for the heat release. In one spatial dimension, the model simplifies to a forced Burgers equation. Through analysis, numerical calculations and comparison with the reactive Euler equations, the model is demonstrated to capture such essential dynamical characteristics of detonations as the steady-state structure, the linear stability spectrum, the period-doubling sequence of bifurcations and chaos in one-dimensional detonations and cellular structures in multidimensional detonations.
In humans, obesity before and during pregnancy is associated with both fetal macrosomia and growth restriction, and long-term cardiovascular risk in the offspring. We aimed to determine whether overweighted pregnant guinea pig sows results in an increased fetal weight at term and the effects on the vascular reactivity in fetal systemic and umbilical arteries. Pregnant guinea pigs were classified as control (n=4) or high weight (HWS, n=5) according to their pre-mating weight, and their fetuses extracted at 0.9 gestation (~60 days). Segments of fetal femoral and umbilical arteries were mounted in a wire myograph, where the contractile response to KCl (5–125 mM), and the relaxation to nitric oxide synthase-dependent agents (insulin, 10−10–10−7 and acetylcholine, 10−10–10−5) and nitric oxide [sodium nitroprusside (SNP), 10−10–10−5] were determined. Fetuses from HWS (HWSF) were grouped according to their body weight as low (<76 g) or high (>85 g) fetal weight, based on the confidence interval (76.5–84.9 g) of the control group. No HWSF were observed in the normal range. Umbilical arteries from HWSF showed a lower response to KCl and insulin compared with controls, but a comparable response with SNP. Conversely, femoral arteries from HWSF showed an increased response to KCl and acetylcholine, along with a decreased sensitivity to SNP. These data show that overweight sows have altered fetal growth along gestation. Further, large and small fetuses from obese guinea pig sows showed altered vascular reactivity at umbilical and systemic vessels, which potentially associates with long-term cardiovascular risk.
Brazil is one of the most important soybean producers in the world. Soybean is a very important crop for the country as it is used for several purposes, from food to biodiesel production. The levels of soybean yield in the different growing regions of the country vary substantially, which results in yield gaps of considerable magnitude. The present study aimed to investigate the soybean yield gaps in Brazil, their magnitude and causes, as well as possible solutions for a more sustainable production. The concepts of yield gaps were reviewed and their values for the soybean crop determined in 15 locations across Brazil. Yield gaps were determined using potential and attainable yields, estimated by a crop simulation model for the main maturity groups of each region, as well as the average actual famers’ yield, obtained from national surveys provided by the Brazilian Government for a period of 32 years (1980–2011). The results showed that the main part of the yield gap was caused by water deficit, followed by sub-optimal crop management. The highest yield gaps caused by water deficit were observed mainly in the south of Brazil, with gaps higher than 1600 kg/ha, whereas the lowest were observed in Tapurah, Jataí, Santana do Araguaia and Uberaba, between 500 and 1050 kg/ha. The yield gaps caused by crop management were mainly concentrated in South-central Brazil. In the soybean locations in the mid-west, north and north-east regions, the yield gap caused by crop management was <500 kg/ha. When evaluating the integrated effects of water deficit and crop management on soybean yield gaps, special attention should be given to Southern Brazil, which has total yield gaps >2000 kg/ha. For reducing the present soybean yield gaps observed in Brazil, several solutions should be adopted by growers, which can be summarized as irrigation, crop rotation and precision agriculture. Improved dissemination of agricultural knowledge and the use of crop simulation models as a tool for improving crop management could further contribute to reduce the Brazilian soybean yield gap.
The split-operator technique for wave packet propagation in quantum systems is expanded here to the case of propagatingwave functions describing Schrödinger particles, namely, charge carriers in semiconductor nanostructures within the effective mass approximation, in the presence of Zeeman effect, as well as of Rashba and Dresselhaus spin-orbit interactions. We also demonstrate that simple modifications to the expanded technique allow us to calculate the time evolution of wave packets describing Dirac particles, which are relevant for the study of transport properties in graphene.
The objective of this study was to evaluate the addition of IGF-I to pig insemination doses stored at 15°C, in conjunction with the addition of different amounts of vitamin E (α-tocopherol). Semen samples (n = 12) from four boars were treated by the addition of different concentrations of vitamin E, ranging up to 400 μg/ml. Immediately after processing and after the doses had been stored at 15°C for 24 or 72 h, samples were warmed at 37°C and 30 ng/ml of IGF-I was added. The assessments were made after 10 and 120 min of IGF-I addition. There was a minor effect of the vitamin E added before cooling and IGF-I added after storage on sperm quality. The addition of 400 μg/ml of vitamin E to diluted semen reduced (P < 0.01) the malondialdehyde (MDA) production in boar semen stored at 15°C for 72 h, regardless of the addition of IGF-I as additive during a 120 min incubation period at 37°C. In these conditions, IGF-I also reduced (P < 0.05) the MDA production in semen samples without addition of vitamin E. IGF-I in the presence of vitamin E reduced (P = 0.03) the glucose intake in freshly diluted boar semen samples before cooling. It was concluded that the addition of 400 μg/ml of vitamin E reduces the MDA production in boar semen stored at 15°C for 72 h, regardless of the presence of IGF-I additive. The addition of IGF-I in doses stored for 72 h with vitamin E ensures higher sperm motility after 120 min of incubation at 37°C.
Tributyrin (TBT) is a TAG composed of three butyric acids that has beneficial effects on ulcerative colitis due to its trophic, anti-inflammatory, pro-apoptotic and anti-carcinogenic properties. The goal of the present study was to evaluate the efficacy and mechanisms of action of TBT supplementation in the prevention of mucosal damage in experimental colitis. Mice received either a control diet or a TBT-supplemented diet for 15 d. Colitis was induced by dextran sodium sulphate administration during the last 7 d. Mucosal damage and the activation of immune cells and cytokines were determined by histological score, flow cytometry and ELISA. Leucocyte rolling and adhesion were assessed by intravital microscopy. Oxidative stress was determined by monitoring hydroperoxide concentration and evaluating superoxide dismutase (SOD) and catalase activities. Intestinal permeability was analysed using diethylenetriaminepentaacetate acid (99mTcDTPA). Compared with the colitis group, the animals in the colitis+TBT group had reduced mucosal damage and neutrophil and eosinophil mucosal infiltration, which were associated with a higher percentage of regulatory T cells (Treg) and higher levels of transforming growth factor β and IL-10 in the lamina propria. The level of in vivo leucocyte adhesion in the colon microvasculature was reduced after TBT supplementation. A lower level of hydroperoxide and higher levels of SOD and catalase activities were associated with TBT supplementation. TBT-supplemented mice showed reduced intestinal permeability to the levels intermediate between the control and colitis groups. In conclusion, the present results show that TBT has positive effects on colonic restructuring in experimental colitis. Additionally, TBT supplementation changes the immune response by controlling inflammation and regulating the expression of anti-inflammatory cytokines and Treg.
A growing body of evidence documents a vast array of economic and social ill-effects of public perceived corruption. These findings and the scant evidence of recent success in the fight against corruption beg the question: how to abate it? We document the existence of a negative, statistically significant and quantitatively large impact of economic freedom (our proxy for institutions of capitalism, markets and competition) on public corruption. This negative response of corruption to economic freedom holds after allowing for non-linearities interacting economic freedom and political rights, endowments, legal families, ethnicity and for robust determinants of corruption uncovered by Daniel Treisman [‘What Have We Learned About the Causes of Corruption From Ten Years of Cross-National Empirical Research?’, Annual Review of Political Science, 10: 211–244], such as income, democracy, freedom of the press and fuel exports. Thus, this paper helps to explain why high-income prosperous countries exhibit low levels of public perceived corruption, and why honesty is a normal good.
Life history traits of Patella candei were studied for the first time, including weight versus length relationship, growth, age structure, sexual maturity, recruitment pattern, mortality rates and yield and biomass-per-recruit of an exploited population in Madeira Island, north-eastern Atlantic using monthly length–frequency data from January to December 1999. The growth pattern of P. candei showed positive allometric nature of growth (b > 3, P < 0.05). The estimated growth parameters showed an asymptotic length (L∞) and growth coefficient (K) estimated at 80.81 mm and K at 0.32 year−1 with a growth performance index (φ′) calculated as 3.32 based on the collected data. This species is moderately long-lived reaching up to 9.36 years and achieving sexual maturity at 36.7 mm of shell length. The recruitment pattern was continuous, displaying a major peak event per year, occurring in January (25.12%). The estimated total mortality rate (Z) was 1.79 year−1 while natural mortality rate (M) was 0.55 year−1 and fishing mortality rate (F) was 1.24 year−1. The probability of capture shows that the length at first capture (Lc) was 42.7 mm, the exploitation rate (E) 0.693 and the maximum allowable limit of exploitation (Emax) was 0.779 for the highest yield. The exploitation rate was less than the predicted Emax values, showing that the stock of P. candei was found to be under-exploited in the investigated area; however, its slow growth and long life make it extremely vulnerable to over-exploitation.
Evolutionary and closer structural relationships are demonstrated by phylogenetic analysis, peptide prediction and molecular modelling between Solanum tuberosum apyrase, Schistosoma mansoni SmATPase 2 and Leishmania braziliensis NDPase. Specific protein domains are suggested to be potentially involved in the immune response, and also seem to be conserved during host and parasite co-evolution. Significant IgG antibody reactivity was observed in sera from patients with American cutaneous leishmaniasis (ACL) and schistosomiasis using potato apyrase as antigen in ELISA. S. mansoni adult worm or egg, L. braziliensis promastigote (Lb) and Trypanosoma cruzi epimastigote (EPI) have ATP diphosphohydrolases, and antigenic preparations of them were evaluated. In ACL patients, IgG seropositivity was about 43% and 90% for Lb and potato apyrase, respectively, while IgM was lower (<19%) for both. In schistosomiasis patients IgM (>40%) or IgG (100%) seropositivity for both soluble egg (SEA) and adult worm (SWAP) antigens was higher than that found for potato apyrase (IgM=10%; IgG=39%). In Chagas disease, IgG seropositivity for EPI and potato apyrase was 97% and 17%, respectively, while the IgM was low (3%) for both antigens. The study of the conserved domains from both parasite proteins and potato apyrase could lead to the development of new drug targets or molecular markers.
Pleonotoma orientalis Sandwith (Bignoniaceae), a poorly known species, is lectotypified, illustrated for the first time and a distribution map is provided. Pleonotoma orientalis Sandwith var. ratteriana Proença & Farias from the Jalapão area (State of Tocantins, Central Brazil) is described and illustrated. The new variety is apparently identical to the typical variety in floral characters but distinct in its ternate-tripinnate leaves with numerous, minute, slightly thickened leaflets, and fruits with rounded or obtuse tips. The collections of this new variety increase its range c.400 km S from Northern Brazil (Maranhão and Pará) into Tocantins in Central Brazil.
We present HST/ACS observations of five regions in the outskirts of M31. Four are centered on prominent stellar overdensities roughly aligned with the major axis. Well-populated colour magnitude diagrams (CMDs) show that these fields differ in morphology from the fifth (Minor Axis) field. Comparisons with isochrones present tantalising evidence that they contain a small contingent of very young (≤ 1Gyr) stars, at odds with what may be expected of typical halo populations, suggesting that this low-latitude substructure could feasibly have formed in the disk.
The outer regions of M31 contain significant substructure. Here we investigate the origins of the substructure in three fields close to the major axis of M31 using colour-magnitude diagrams produced from HST-ACS.
Pollens appear like a fine to coarse powder that is liberated by the
microsporangia of Gimnosperms and Angiosperms. The pollen grain wall,
the sporoderm, envelopes the microgametophytes (male gametophytes),
which produce the male gametes of seed plants. Pollen grains are
interesting from the material science point of view since the native
polymer, the sporopollenin, found in the sporoderm outer layer (exine),
is one of the toughest known materials which is degraded by oxidation
but is resistant to reduction. This property permits the sporopollenin
persistence as an unaltered polymer in sediments of great age, e.g the
Ordovician period, 400 million years ago. Sporopollenin is a mixture of
fatty acids, phenyl-derivatives as p-coumaric acid, and carotenes .
Its nanostructure is not yet completed revealed. Therefore, more studies
must be performed. A number of models have been proposed for the
sporopollenin nanostructure of spores and pollen grains . Rowley et
al. [3-4] interpret exine structure as being formed by helical subunits,
based on transmission and scanning electron microscope (TEM and SEM)
studies. The atomic force microscopy (AFM) is the ideal method to study
the sporopollenin nanostructure  since the arrangement of components
is not visualized easily through other microscope techniques (e.g. TEM
and SEM). In the present work, we used AFM to study the sporopollenin
nanostructure of the Ilex paraguariensis A.St.Hil. exine, an Angiosperm
Atomic Force Microscopy (AFM) is a recent technique that allows
evaluation of features in biological systems that could not be
previously observed by other instruments. Red Blood Cells (RBC) have
been extensively studied because of their relatively simple membrane
structure, convenience of preparation and scanning . As an ancillary
way of confirming diagnoses, AFM has mostly been used to determine shape
and size of RBCs, which are important indicators of some blood diseases
or disordered erythropoiesis . In Myelodysplastic Syndrome (MDS)
hematopoiesis is inefficacious with consequent anemia that may evolve to
acute leukemia. Genomic alterations lead to structural defects in the
biomolecular network that forms the erythrocyte membrane. The
deformation capability of the cells and their lifetime in circulation
are diminished . AFM allows us to observe in a controlled way the
response of these membrane molecular networks under physical and
chemical stimuli in many different physiological conditions, such as in
air and liquids . Using this technique, many new characteristics have
been found in erythrocyte membranes that are still of undetermined
significance [3,4]. The aim of our work is to compare membrane
morphology of two groups of blood donors, that is, healthy subjects and
patients with MDS. The images yielded by AFM confirm the structure of
the erythrocytes and reveal interesting submicron features on the cell,
suggesting a way to distinguish between RBCs from healthy donors and
RBCs from patients with MDS.