962 resultados para MIXED-SPECIES MALARIA


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Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at the effect of removal of a non-native tree species (Mimosa caesalpiniifolia) on the understory of a semideciduous forest undergoing restoration. We assessed two 14-year-old plantation systems (modified taungya agroforestry system; and mixed plantation using commercial timber and firewood tree species) established at two sites with contrasting soil properties in São Paulo state, Brazil. The experimental design included randomized blocks with split plots. The natural regeneration of woody species (height ≥0.2 m) was compared between managed (all M. caesalpiniifolia trees removed) and unmanaged plots during the first year after the intervention. The removal of M. caesalpiniifolia increased species diversity but decreased stand basal area. Nevertheless, the basal area loss was recovered after 1 year. The management treatment affected tree species regeneration differently between species groups. The results of this study suggest that removal of M. caesalpiniifolia benefited the understory and possibly accelerated the succession process. Further monitoring studies are needed to evaluate the longer term effects on stand structure and composition. The lack of negative effects of tree removal on the natural regeneration indicates that such interventions can be recommended, especially considering the expectations of economic revenues from tree harvesting in restoration plantings.

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In this article we present the plants used for the treatment of malaria and associated symptoms in Santa Isabel do Rio Negro in the Brazilian Amazon. The region has important biological and cultural diversities including more than twenty indigenous ethnic groups and a strong history in traditional medicine. The aims of this study are to survey information in the Baniwa, Baré, Desana, Piratapuia, Tariana, Tukano, Tuyuca, Yanomami ethnic communities and among caboclos (mixed-ethnicity) on: a) plant species used for the treatment of malaria and associated symptoms; b) dosage forms and c) distribution of these anti-malarial plants in the Amazon. Information was obtained through classical ethnobotanical and ethnopharmacological methods from interviews with 146 informants in Santa Isabel municipality on the upper Negro River, Brazil. Fifty-five mainly native neotropical plant species from 34 families were in use. The detailed uses of these plants were documented. The result was 187 records (64.4%) of plants for the specific treatment of malaria, 51 records (17.5%) of plants used in the treatment of liver problems and 28 records (9.6%) of plants used in the control of fevers associated with malaria. Other uses described were blood fortification ('dar sangue'), headache and prophylaxis. Most of the therapeutic preparations were decoctions and infusions based on stem bark, root bark and leaves. These were administered by mouth. In some cases, remedies were prepared with up to three different plant species. Also, plants were used together with other ingredients such as insects, mammals, gunpowder and milk. This is the first study on the anti-malarial plants from this region of the Amazon. Aspidosperma spp. and Ampelozizyphus amazonicus Ducke were the most cited species in the communities surveyed. These species have experimental proof supporting their anti-malarial efficacy. The dosage of the therapeutic preparations depends on the kind of plant, quantity of plant material available, the patient's age (children and adults) and the local expert. The treatment time varies from a single dose to up to several weeks. Most anti-malarial plants are domesticated or grow spontaneously. They are grown in home gardens, open areas near the communities, clearings and secondary forests, and wild species grow in areas of seasonally flooded wetlands and terra firme (solid ground) forest, in some cases in locations that are hard to access. Traditional knowledge of plants was found to be falling into disuse presumably as a consequence of the local official health services that treat malaria in the communities using commercial drugs. Despite this, some species are used in the prevention of this disease and also in the recovery after using conventional anti-malarial drugs.

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The issue of whether loliginid squid can influence the average structure of marine ecosystems in a keystone role, i.e. a strong effect with relatively low biomass, has not yet been examined. Here, the diet of Loligo plei in inner shelf waters of the South Brazil Bight was examined, as a first step, based on the stomach contents of 2200 squid hand-jigged in shallow water (, 30 m) and taken as bycatch of shrimp trawlers in deeper water (30-100 m). Diet varied by size, season, and fishing zone. Stomachs were not empty in similar to 12%, with more empty during winter. The range of mantle lengths of squid caught by jigging (101-356 mm) appeared to differ from the squid trawled (30-236 mm), and the diet also differed. Food categories recorded in deeper water did not include amphipods or polychaetes, but in both fishing areas, fish were the most common prey. The fish prey identified included Trachurus lathami, small pelagic species, trichiurids, and Merluccius hubbsi. Demersal species, such as Ctenosciaena gracilicirrhus, and flatfish were also present. An ecosystem network model is updated through which a mixed-trophic impact matrix and ""keystoneness"" indicators were calculated. Loligo plei represents an important link between pelagic and demersal energy pathways, with high indices of keystoneness.

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Sugarcane-breeding programs take at least 12 years to develop new commercial cultivars. Molecular markers offer a possibility to study the genetic architecture of quantitative traits in sugarcane, and they may be used in marker-assisted selection to speed up artificial selection. Although the performance of sugarcane progenies in breeding programs are commonly evaluated across a range of locations and harvest years, many of the QTL detection methods ignore two- and three-way interactions between QTL, harvest, and location. In this work, a strategy for QTL detection in multi-harvest-location trial data, based on interval mapping and mixed models, is proposed and applied to map QTL effects on a segregating progeny from a biparental cross of pre-commercial Brazilian cultivars, evaluated at two locations and three consecutive harvest years for cane yield (tonnes per hectare), sugar yield (tonnes per hectare), fiber percent, and sucrose content. In the mixed model, we have included appropriate (co)variance structures for modeling heterogeneity and correlation of genetic effects and non-genetic residual effects. Forty-six QTLs were found: 13 QTLs for cane yield, 14 for sugar yield, 11 for fiber percent, and 8 for sucrose content. In addition, QTL by harvest, QTL by location, and QTL by harvest by location interaction effects were significant for all evaluated traits (30 QTLs showed some interaction, and 16 none). Our results contribute to a better understanding of the genetic architecture of complex traits related to biomass production and sucrose content in sugarcane.

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Two structural properties in mixed alkali metal phosphate glasses that seem to be crucial to the development of the mixed ion effect in dc conductivity were systematically analyzed in Na mixed metaphosphates: the local order around the mobile species, and their distribution and mixing in the glass network. The set of glasses considered here, Na1-xMxPO3 with M = Li, Ag, K, Rb, and Cs and 0 <= x <= 1, encompass a broad degree of size mismatch between the mixed cation species. A comprehensive solid-state nuclear magnetic resonance study was carried out using P-31 MAS, Na-23 triple quantum MAS, Rb-87 QCPMG, P-31-Na-23 REDOR, Na-23-Li-7 and Li-7-Li-6 SEDOR, and Na-23 spin echo decay. It was observed that the arrangement of P atoms around Na in the mixed glasses was indistinguishable from that observed in the NaPO3 glass. However, systematic distortions in the local structure of the 0 environments around Na were observed, related to the presence of the second cation. The average Na-O distances show an expansion/compression When Na+ ions are replaced by cations with respectively smaller/bigger radii. The behavior of the nuclear electric quadrupole coupling. constants indicates that this expansion reduces the local symmetry, while the compression produces the opposite effect These effects become marginally small when the site mismatch between the cations is small, as in Na-Ag mixed glasses. The present study confirms the intimate mixing of cation species at the atomic scale, but clear deviations from random mixing were detected in systems with larger alkali metal ions (Cs-Na, K-Na, Rb-Na). In contrast, no deviations from the statistical ion mixture were found in the systems Ag-Na and Li-Na, where mixed cations are either of radii comparable to (Ag+) or smaller than (Li+) Na+. The set of results supports two fundamental structural features of the models proposed to explain the mixed ion effect: the. structural specificity of the sites occupied by each cation species and their mixing at the atomic scale.

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The malaria parasite Plasmodium falciparum proliferates within human erythrocytes and is thereby exposed to a variety of reactive oxygen species (ROS) such as hydrogen peroxide, hydroxyl radical, superoxide anion, and highly reactive singlet oxygen (1O2). While most ROS are already well studied in the malaria parasite, singlet oxygen has been neglected to date. In this study we visualized the generation of 1O2 by live cell fluorescence microscopy using 3-(p-aminophenyl) fluorescein as an indicator dye. While 1O2 is found restrictively in the parasite, its amount varies during erythrocytic schizogony. Since the photosensitizer cercosporin generates defined amounts of 1O2 we have established a new cytometric method that allows the stage specific quantification of 1O2. Therefore, the parasites were first classified into three main stages according to their respective pixel-area of 200600 pixels for rings, 7001,200 pixels for trophozoites and 1,4002,500 pixels for schizonts. Interestingly the highest mean concentration of endogenous 1O2 of 0.34 nM is found in the trophozoites stage, followed by 0.20 nM (ring stage) and 0.10 nM (schizont stage) suggesting that 1O2 derives predominantly from the digestion of hemoglobin. (c) 2012 International Society for Advancement of Cytometry

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SERA5 is regarded as a promising malaria vaccine candidate of the most virulent human malaria parasite Plasmodium falciparum. SERA5 is a 120 kDa abundantly expressed blood-stage protein containing a papain-like protease. Since substantial polymorphism in blood-stage vaccine candidates may potentially limit their efficacy, it is imperative to fully investigate polymorphism of the SERA5 gene (sera5). In this study, we performed evolutionary and population genetic analysis of sera5. The level of inter-species divergence (kS = 0.076) between P. falciparum and Plasmodium reichenowi, a closely related chimpanzee malaria parasite is comparable to that of housekeeping protein genes. A signature of purifying selection was detected in the proenzyme and enzyme domains. Analysis of 445 near full-length P. falciparum sera5 sequences from nine countries in Africa, Southeast Asia, Oceania and South America revealed extensive variations in the number of octamer repeat (OR) and serine repeat (SR) regions as well as substantial level of single nucleotide polymorphism (SNP) in non-repeat regions (2562 bp). Remarkably, a 14 amino acid sequence of SERA5 (amino acids 59-72) that is known to be the in vitro target of parasite growth inhibitory antibodies was found to be perfectly conserved in all 445 worldwide isolates of P. falciparum evaluated. Unlike other major vaccine target antigen genes such as merozoite surface protein-1, apical membrane antigen-1 or circumsporozoite protein, no strong evidence for positive selection was detected for SNPs in the non-repeat regions of sera5. A biased geographical distribution was observed in SNPs as well as in the haplotypes of the sera5 OR and SR regions. In Africa, OR- and SR-haplotypes with low frequency (<5%) and SNPs with minor allele frequency (<5%) were abundant and were mostly continent-specific. Consistently, significant genetic differentiation, assessed by the Wright's fixation index (FST) of inter-population variance in allele frequencies, was detected for SNPs and both OR- and SR-haplotypes among almost all parasite populations. The exception was parasite populations between Tanzania and Ghana, suggesting frequent gene flow in Africa. The present study points to the importance of investigating whether biased geographical distribution for SNPs and repeat variants in the OR and SR regions affect the reactivity of human serum antibodies to variants. (C) 2011 Elsevier Ltd. All rights reserved.

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This study contributes to knowledge of Anopheles species, including vectors of Plasmodium from the western Brazilian Amazon in Porto Velho, Rondonia State. The sampling area has undergone substantial environmental changes as a consequence of agricultural and hydroelectric projects, which have caused intensive deforestation and favored habitats for some mosquito species. The purpose of this study was to diagnose the occurrence of anopheline species from collections in three locations along an electric-power transmission line. Each locality was sampled three times from 2010 to 2011. The principal adult mosquitoes captured in Shannon trap were Anopheles darlingi, An. triannulatus, An. nuneztovari l.s., An. gilesi and An. costai. In addition, larvae were collected in ground breeding sites for Anopheles braziliensis, An. triannulatus, An. darlingi, An. deaneorum, An. marajoara, An. peryassui, An. nuneztovari l.s. and An. oswaldoi-konderi. Anopheles darlingi was the most common mosquito in the region. We discuss Culicidae systematics, fauna distribution, and aspects of malaria in altered habitats of the western Amazon.

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Glasses in the system [Na2S](2/3)[(B2S3)(x)(P2S5)(1-x)](1/3) (0.0 <= x <= 1.0) were prepared by the melt quenching technique, and their properties were characterized by thermal analysis and impedance spectroscopy. Their atomic-level structures were comprehensively characterized by Raman spectroscopy and B-11, P-31, and Na-23 high resolution solid state magic-angle spinning (MAS) NMR techniques. P-31 MAS NMR peak assignments were made by the presence or absence of homonuclear indirect P-31-P-31 spin-spin interactions as detected using homonuclear J-resolved and refocused INADEQUATE techniques. The extent of B-S-P connectivity in the glassy network was quantified by P-31{B-11} and B-11{P-31} rotational echo double resonance spectroscopy. The results clearly illustrate that the network modifier alkali sulfide, Na2S, is not proportionally shared between the two network former components, B and P. Rather, the thiophosphate (P) component tends to attract a larger concentration of network modifier species than predicted by the bulk composition, and this results in the conversion of P2S74-, pyrothiophosphate, Na/P = 2:1, units into PS43-, orthothiophosphate, Na/P = 3:1, groups. Charge balance is maintained by increasing the net degree of polymerization of the thioborate (B) units through the formation of covalent bridging sulfur (BS) units, B S B. Detailed inspection of the B-11 MAS NMR spectra reveals that multiple thioborate units are formed, ranging from neutral BS3/2 groups all the way to the fully depolymerized orthothioborate (BS33-) species. On the basis of these results, a comprehensive and quantitative structural model is developed for these glasses, on the basis of which the compositional trends in the glass transition temperatures (T-g) and ionic conductivities can be rationalized. Up to x = 0.4, the dominant process can be described in a simplified way by the net reaction equation P-1 + B-1 reversible arrow P-0 + B-4, where the superscripts denote the number of BS atoms for the respective network former species. Above x = 0.4, all of the thiophosphate units are of the P-0 type and both pyro-(B-1) and orthothioborate (B-0) species make increasing contributions to the network structure with increasing x. In sharp contrast to the situation in sodium borophosphate glasses, four-coordinated thioborate species are generally less abundant and heteroatomic B-S-P linkages appear to not exist. On the basis of this structural information, compositional trends in the ionic conductivities are discussed in relation to the nature of the charge-compensating anionic species and the spatial distribution of the charge carriers.

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Background: Anopheles (Kerteszia) cruzii is a primary vector of Plasmodium parasites in Brazil's Atlantic Forest. Adult females of An. cruzii and An. homunculus, which is a secondary malaria vector, are morphologically similar and difficult to distinguish when using external morphological characteristics only. These two species may occur syntopically with An. bellator, which is also a potential vector of Plasmodium species and is morphologically similar to An. cruzii and An. homunculus. Identification of these species based on female specimens is often jeopardised by polymorphisms, overlapping morphological characteristics and damage caused to specimens during collection. Wing geometric morphometrics has been used to distinguish several insect species; however, this economical and powerful tool has not been applied to Kerteszia species. Our objective was to assess wing geometry to distinguish An. cruzii, An. homunculus and An. bellator. Methods: Specimens were collected in an area in the Serra do Mar hotspot biodiversity corridor of the Atlantic Forest biome (Cananeia municipality, State of Sao Paulo, Brazil). The right wings of females of An. cruzii (n= 40), An. homunculus (n= 50) and An. bellator (n= 27) were photographed. For each individual, 18 wing landmarks were subjected to standard geometric morphometrics. Discriminant analysis of Procrustean coordinates was performed to quantify wing shape variation. Results: Individuals clustered into three distinct groups according to species with a slight overlap between representatives of An. cruzii and An. homunculus. The Mahalanobis distance between An. cruzii and An. homunculus was consistently lower (3.50) than that between An. cruzii and An. bellator (4.58) or An. homunculus and An. bellator (4.32). Pairwise cross-validated reclassification showed that geometric morphometrics is an effective analytical method to distinguish between An. bellator, An. cruzii and An. homunculus with a reliability rate varying between 78-88%. Shape analysis revealed that the wings of An. homunculus are narrower than those of An. cruzii and that An. bellator is different from both of the congeneric species. Conclusion: It is possible to distinguish among the vectors An. cruzii, An. homunculus and An. bellator based on female wing characteristics.

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Glasses in the system xGeO(2)-(1-x)NaPO3 (0 <= x <= 0.50) were prepared by conventional melting quenching and characterized by thermal analysis, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and P-31 nuclear magnetic resonance (MAS NMR) techniques. The deconvolution of the latter spectra was aided by homonuclear J-resolved and refocused INADEQUATE techniques. The combined analyses of P-31 MAS NMR and O-1s XPS lineshapes, taking charge and mass balance considerations into account, yield the detailed quantitative speciations of the phosphorus, germanium, and oxygen atoms and their respective connectivities. An internally consistent description is possible without invoking the formation of higher-coordinated germanium species in these glasses, in agreement with experimental evidence in the literature. The structure can be regarded, to a first approximation, as a network consisting of P-(2) and P-(3) tetrahedra linked via four-coordinate germanium. As implied by the appearance of P-(3) units, there is a moderate extent of network modifier sharing between phosphate and germanate network formers, as expressed by the formal melt reaction P-(2) + Ge-(4) -> P-(3) + Ge-(3). The equilibrium constant of this reaction is estimated as K = 0.52 +/- 0.11, indicating a preferential attraction of network modifier by the phosphorus component. These conclusions are qualitatively supported by Raman spectroscopy as well as P-31{Na-23} and P-31{Na-23} rotational echo double resonance (REDOR) NMR results. The combined interpretation of O-1s XPS and P-31 MAS NMR spectra shows further that there are clear deviations from a random connectivity scenario: heteroatomic P-O-Ge linkages are favored over homoatomic P-O-P and Ge-O-Ge linkages.

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Baccharis napaea, a new species belonging to subgen. Tarchonanthoides sect. Coridifoliae is described and illustrated. The new species is compared to and distinguished from the sympatric species B. coridifolia, B. erigeroides, and B. scabrifolia, and from the allopatric B. bicolor. Baccharis napaea occurs in open subtropical highland grasslands and the edges and open glades of subtropical mixed forests on the south Brazilian plateau. Additionally, a distribution map and description of habitat and conservation status of the new species are presented.

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Trypanosoma (Megatrypanum) melophagium is a parasite of sheep transmitted by sheep keds, the sheep-restricted ectoparasite Melophagus ovinus (Diptera: Hippoboscidae). Sheep keds were 100% prevalent in sheep from five organic farms in Croatia, Southeastern Europe, whereas trypanosomes morphologically compatible with T. melophagium were 86% prevalent in the guts of the sheep keds. Multilocus phylogenetic analyses using sequences of small subunit rRNA, glycosomal glyceraldehyde-3-phosphate dehydrogenase, spliced leader, and internal transcribed spacer 1 of the rDNA distinguished T. melophagium from all allied trypanosomes from other ruminant species and placed the trypanosome in the subgenus Megatrypanum. Trypanosomes from sheep keds from Croatia and Scotland, the only available isolates for comparison, shared identical sequences. All biologic and phylogenetic inferences support the restriction of T. melophagium to sheep and, especially, to the sheep keds. The comparison of trypanosomes from sheep, cattle, and deer from the same country, which was never achieved before this work, strongly supported the host-restricted specificity of trypanosomes of the subgenus Megatrypanum. Our findings indicate that with the expansion of organic farms, both sheep keds and T. melophagium may re-emerge as parasitic infections of sheep.

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Abstract Background Extra-Amazonian autochthonous Plasmodium vivax infections have been reported in mountainous regions surrounded by the Atlantic Forest in Espírito Santo state, Brazil. Methods Sixty-five patients and 1,777 residents were surveyed between April 2001 and March 2004. Laboratory methods included thin and thick smears, multiplex-PCR, immunofluorescent assay (IFA) against P. vivax and Plasmodium malariae crude blood-stage antigens and enzyme-linked immunosorbent assay (ELISA) for antibodies against the P. vivax-complex (P. vivax and variants) and P. malariae/Plasmodium brasilianum circumsporozoite-protein (CSP) antigens. Results Average patient age was 35.1 years. Most (78.5%) were males; 64.6% lived in rural areas; 35.4% were farmers; and 12.3% students. There was no relevant history of travel. Ninety-five per cent of the patients were experiencing their first episode of malaria. Laboratory data from 51 patients were consistent with P. vivax infection, which was determined by thin smear. Of these samples, 48 were assayed by multiplex-PCR. Forty-five were positive for P. vivax, confirming the parasitological results, while P. malariae was detected in one sample and two gave negative results. Fifty percent of the 50 patients tested had IgG antibodies against the P. vivax-complex or P. malariae CSP as determined by ELISA. The percentages of residents with IgM and IgG antibodies detected by IFA for P. malariae, P. vivax and Plasmodium falciparum who did not complain of malaria symptoms at the time blood was collected were 30.1% and 56.5%, 6.2% and 37.7%, and 13.5% and 13%, respectively. The same sera that reacted to P. vivax also reacted to P. malariae. The following numbers of samples were positive in multiplex-PCR: 23 for P. vivax; 15 for P. malariae; 9 for P. falciparum and only one for P. falciparum and P. malariae. All thin and thick smears were negative. ELISA against CSP antigens was positive in 25.4%, 6.3%, 10.7% and 15.1% of the samples tested for "classical" P. vivax (VK210), VK247, P. vivax-like and P. malariae, respectively. Anopheline captures in the transmission area revealed only zoophilic and exophilic species. Conclusion The low incidence of malaria cases, the finding of asymptomatic inhabitants and the geographic separation of patients allied to serological and molecular results raise the possibility of the existence of a simian reservoir in these areas.

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Abstract Background In areas with limited structure in place for microscopy diagnosis, rapid diagnostic tests (RDT) have been demonstrated to be effective. Method The cost-effectiveness of the Optimal® and thick smear microscopy was estimated and compared. Data were collected on remote areas of 12 municipalities in the Brazilian Amazon. Data sources included the National Malaria Control Programme of the Ministry of Health, the National Healthcare System reimbursement table, hospitalization records, primary data collected from the municipalities, and scientific literature. The perspective was that of the Brazilian public health system, the analytical horizon was from the start of fever until the diagnostic results provided to patient and the temporal reference was that of year 2006. The results were expressed in costs per adequately diagnosed cases in 2006 U.S. dollars. Sensitivity analysis was performed considering key model parameters. Results In the case base scenario, considering 92% and 95% sensitivity for thick smear microscopy to Plasmodium falciparum and Plasmodium vivax, respectively, and 100% specificity for both species, thick smear microscopy is more costly and more effective, with an incremental cost estimated at US$549.9 per adequately diagnosed case. In sensitivity analysis, when sensitivity and specificity of microscopy for P. vivax were 0.90 and 0.98, respectively, and when its sensitivity for P. falciparum was 0.83, the RDT was more cost-effective than microscopy. Conclusion Microscopy is more cost-effective than OptiMal® in these remote areas if high accuracy of microscopy is maintained in the field. Decision regarding use of rapid tests for diagnosis of malaria in these areas depends on current microscopy accuracy in the field.