Are light traps baited with kairomones effective in the capture of Lutzomyia longipalpis and Lutzomyia intermedia? An evaluation of synthetic human odor as an attractant for phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae)

Phlebotomine sand flies are often captured with human bait and/or light traps, either with or without an animal bait. More recently, synthetic attractants have been used as bait in traps to improve the capture of phlebotomine sand flies as well as other insects of medical and veterinary importance. The aim of the present study was to evaluate the effects of the kairomone 1-octen-3-ol (octenol) and the synthetic human odor BG-Mesh LureTM (BGML - lactic acid, caproic acid and ammonia) baited in modified CDC light traps on the capture of phlebotomine sand flies. The experiments followed the 5x5 Latin square design. Among the species caught, Lutzomyia intermedia apparently presented a dose-dependent response to octenol. The response obtained with the BGML, alone or in combination with octenol (5 mg/h), indicated some degree of attractiveness of these baits to different phlebotomine sand fly species. Octenol seems to be more attractive to L. intermedia than to Lutzomyia longipalpis, while the BGML presented a higher success in capturing L. longipalpis. When the components of the BGML were used separately, there was no increase in catching the female of L. intermedia. Apparently, there was no synergistic effect between the octenol and the BGML. In conclusion, the octenol and the BGML were demonstrated to be possible baits to attract some phlebotomine sand fly species.

Biological activity of neosergeolide and isobrucein B (and two semi-synthetic derivatives) isolated from the Amazonian medicinal plant Picrolemma sprucei (Simaroubaceae)

In the present study, in vitro techniques were used to investigate a range of biological activities of known natural quassinoids isobrucein B (1) and neosergeolide (2), known semi-synthetic derivative 1,12-diacetylisobrucein B (3), and a new semi-synthetic derivative, 12-acetylneosergeolide (4). These compounds were evaluated for general toxicity toward the brine shrimp species Artemia franciscana, cytotoxicity toward human tumour cells, larvicidal activity toward the dengue fever mosquito vector Aedes aegypti, haemolytic activity in mouse erythrocytes and antimalarial activity against the human malaria parasite Plasmodium falciparum. Compounds 1 and 2 exhibited the greatest cytotoxicity against all the tumor cells tested (IC50 = 5-27 µg/L) and against multidrug-resistant P. falciparum K1 strain (IC50 = 1.0-4.0 g/L) and 3 was only cytotoxic toward the leukaemia HL-60 strain (IC50 = 11.8 µg/L). Quassinoids 1 and 2 (LC50 = 3.2-4.4 mg/L) displayed greater lethality than derivative 4 (LC50 = 75.0 mg/L) toward A. aegypti larvae, while derivative 3 was inactive. These results suggest a novel application for these natural quassinoids as larvicides. The toxicity toward A. franciscana could be correlated with the activity in several biological models, a finding that is in agreement with the literature. Importantly, none of the studied compounds exhibited in vitro haemolytic activity, suggesting specificity of the observed cytotoxic effects. This study reveals the biological potential of quassinoids 1 and 2 and to a lesser extent their semi-synthetic derivatives for their in vitro antimalarial and cytotoxic activities.

Immunostimulatory property of a synthetic peptide belonging to the soluble ATP diphosphohydro-lase isoform (SmATPDase 2) and immunolocalisation of this protein in the Schistosoma mansoni egg

A peptide (SmB2LJ; r175-194) that belongs to a conserved domain from Schistosoma mansoni SmATPDase 2 and is shared with potato apyrase, as predicted by in silico analysis as antigenic, was synthesised and its immunostimulatory property was analysed. When inoculated in BALB/c mice, this peptide induced high levels of SmB2LJ-specific IgG1 and IgG2a subtypes, as detected by enzyme linked immunosorbent assay. In addition, dot blots were found to be positive for immune sera against potato apyrase and SmB2LJ. These results suggest that the conserved domain r175-194 from the S. mansoni SmATPDase 2 is antigenic. Western blots were performed and the anti-SmB2LJ antibody recognised in adult worm (soluble worm antigen preparation) or soluble egg antigen antigenic preparations two bands of approximately 63 and 55 kDa, molecular masses similar to those predicted for adult worm SmATPDase 2. This finding strongly suggests the expression of this same isoform in S. mansoni eggs. To assess localisation of SmATPDase 2, confocal fluorescence microscopy was performed using cryostat sections of infected mouse liver and polyclonal antiserum against SmB2LJ. Positive reactions were identified on the external surface from the miracidium in von Lichtenberg's envelope and, in the outer side of the egg-shell, showing that this soluble isoform is secreted from the S. mansoni eggs.

Immunologic evaluation and validation of methods using synthetic peptides derived from Mycobacterium tuberculosis for the diagnosis of tuberculosis infection

The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection.

Estimation of surface roughness in a semiarid region from C-band ERS-1 synthetic aperture radar data

In this study, we investigated the feasibility of using the C-band European Remote Sensing Satellite (ERS-1) synthetic aperture radar (SAR) data to estimate surface soil roughness in a semiarid rangeland. Radar backscattering coefficients were extracted from a dry and a wet season SAR image and were compared with 47 in situ soil roughness measurements obtained in the rocky soils of the Walnut Gulch Experimental Watershed, southeastern Arizona, USA. Both the dry and the wet season SAR data showed exponential relationships with root mean square (RMS) height measurements. The dry C-band ERS-1 SAR data were strongly correlated (R² = 0.80), while the wet season SAR data have somewhat higher secondary variation (R² = 0.59). This lower correlation was probably provoked by the stronger influence of soil moisture, which may not be negligible in the wet season SAR data. We concluded that the single configuration C-band SAR data is useful to estimate surface roughness of rocky soils in a semiarid rangeland.

Activity of phosphorus of synthetic Fe-K-P compounds in superphosphate fertilizers as affected by pH and ionic strength

The concentration of orthophosphate ions released from Fe-K-P compounds (Fe3KH8(PO4)6 .6H2O and Fe3KH14(PO4)8 .4H2O) present in superphosphates increases with pH, which initially suggests that the agronomic effectiveness of P fertilizers containing high amounts of these compounds would also increase with soil pH but studies considering activity, instead of concentration, are necessary. With this purpose, both compounds were synthesized under laboratory conditions, characterized by elemental chemical analysis, optical microscopy, X ray diffractometry, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and used in a solubility study. Solutions of 0.01, 0.05 and 0.1 mol L-1 NaCl with pH adjusted to 3.0, 4.0, 5.0, 5.5, 6.0, 6.5, 7.0 and 7.5 were prepared for the solubility study of H8-syn, H14-syn and a phosphate rock (PR) from Brazil. The orthophosphate activity as H2PO4- and HPO4(2-) was calculated in each situation as related to pH and ionic strength using software MINTEQ. The remaining precipitates after equilibrium were chemically analyzed and subjected to X ray, SEM and EDS. Results of chemical analysis and instrumental techniques confirmed the preparation method. The activity of orthophosphate ions of both compounds tended to decrease under increasing pH and/or ionic strength of the solution, which in turn suggests that an increase in the solution pH does not necessarily promote an increase in the P bioavailability for plant uptake. This can be important when evaluating agronomic data of P fertilizers with high contents of these two Fe-K-P compounds.

Cristallochemical characterization of synthetic Zn-substituted maghemites (g-Fe2-xZn xO3)

Maghemite (g-Fe2O3) is the most usually found ferrimagnetic oxide in red basalt-derived soils. The variable degrees of ionic substitution of Fe3+ for different metals (e.g. Ti4+, Al3+, Mg2+, Zn2+, and Mn2+) and non-metals in the maghemite structure influence some cristallochemical features of this iron oxide. In this study, synthetic Zn-substituted maghemites were prepared by co-precipitation in alkaline aqueous media of FeSO4.7H2O with increasing amounts of ZnSO4.7H2O to obtain the following sequence of Fe3+ for Zn2+ substitutions: 0.0, 0.025, 0.05, 0.10, 0.15, 0.20, and 0.30 mol mol-1. The objective of this work was to evaluate the cristallochemical alterations of synthetic Zn-substituted maghemites. The dark black synthetic precipitated material was heated to 250 °C during 4 h forming a brownish maghemite that was characterized by chemical analysis as well as X ray diffraction (XRD), specific surface area and mass-specific magnetic susceptibility. The isomorphic substitution levels observed were of 0.0013, 0.0297, 0.0590, 0.1145, 0.1764, 0.2292 and 0.3404 mol mol-1, with the formation of a series of maghemites from Fe2Zn0O3 to Fe(1.49)Zn(0.770)O3 . The increase in Fe3+ for Zn2+ substitution, [Zn mol mol-1] increased the dimension a0 of the cubic unit cells of the studied maghemites according to the regression equation: a0 = 0.8343 + 0.02591Zn (R² = 0.98). On the other hand, the mean crystallite dimension and mass-specific magnetic susceptibility of the studied maghemites decreased with increasing isomorphic substitution.

Synthetic sex pheromone of citrus leafminer in Brazilian citrus groves

The objective of this work was to determine the best conditions of use of the synthetic sex pheromone of Phyllocnistis citrella Stainton for monitoring this species in citrus groves in northeastern Brazil. Pheromone doses (0.0, 0.1, 1, 10 and 100 μg) and longevity (1, 15, 29, 43 and 57-day-old lures) and trap height (0.5, 1.5 and 2.5 m), color (green, red, and white) and model influence on P. citrella males capture were evaluated. The doses of 10 and 100 μg of the synthetic sex pheromone - a 3:1 blend of (Z,Z,E)-7,11,13-hexadecatrienal and (Z,Z)-7,11-hexadecadienal - attracted the greatest number of P. citrella males. Traps baited with these two both dosages continued to capture P. citrella males at a comparable rate for over eight weeks in citrus groves. Although there was no significant decrease in activity of both dosages until 57 days of exposure to the environment, the higher dose, as time passed, attracted significantly more P. citrella males than the lower dose. There were no significant differences in male capture in traps with synthetic sex pheromone placed at 1.5 and 2.5 m height, wich had the better results. Trap color and model did not affect male capture.

The wide synthetic versatility of five membered rings containing phosphorus

The chemistry of cyclopentadiene rings has been widely studied. This review article deals with a similar chemistry of new compounds containing from 1 to 5 phosphorus atoms on the ring substituting the carbon atoms. The neutral rings containing one, two and three phosphorus atoms can be used as building blocks for the synthesis of new organic compounds containing phosphorus. These rings plus the anionic ones also show great potential as ligands in coordination chemistry. The aim of this article is to show how important this new area is and how diverse the chemistry related to a single type of ring can be.

Novas tendências no tratamento de efluentes têxteis

Textile effluents, when not correctly treated, cause a high impact to the environment. The main recalcitrant compounds present in textile effluent are represented by the synthetic dyes, used during the fibber dying process. Among others, the azo dyes are considered the most harmful due to its mutagenic and carcinogenic character. In the present work we reported a revision study on the new tendencies for remediation of textile effluents, mainly to degrade the recalcitrant compounds. For this purpose, chemical, physical, photochemical, biological and combined processes were investigated.

Antimycobacterial and cytotoxicity activity of synthetic and natural compounds

Antimycobacterial and cytotoxicity activity of synthetic and natural compounds. Secondary metabolites from Curvularia eragrostidis and Drechslera dematioidea, Clusia sp. floral resin, alkaloids from Pilocarpus alatus, salicylideneanilines, piperidine amides, the amine 1-cinnamylpiperazine and chiral pyridinium salts were assayed on Mycobacterium tuberculosis H37Rv. N-(salicylidene)-2-hydroxyaniline was the most effective compound with a minimal inhibitory concentration (MIC) of 8 µmol/L. Dihydrocurvularin was moderately effective with a MIC of 40 µmol/L. Clusia sp. floral resin and a gallocatechin-epigallocatechin mixture showed MIC of 0.02 g/L and 38 µmol/L, respectively. The cytotoxicity was evaluated for N-(salicylidene)-2-hydroxyaniline, curvularin, dihydrocurvularin and Clusia sp. floral resin, and the selectivity indexes were > 125, 0.47, 0.75 and 5, respectively.

Avaliação da biodegradabilidade de efluentes têxteis do beneficiamento secundário de malhas de poliéster tratados com Reagente de Fenton

From the environmental point of view, the textile sector is outstanding for the generation of large amounts of biorecalcitrant effluents. In this paper the textile effluent biodegradability, both before and after its treatment with Fenton's Reagent, were compared by means of biologic tests. These tests showed that the Fenton treatment lowered the biodegradabilty of practically all tested effluents, except one specific effluent from a scouring bath of polyester fibers, which achieved a 93% COD removal. This removal was due to a significant phase separation (oil/water).

Descoloração de corantes industriais e efluentes têxteis simulados por peroxidase de nabo (Brassica campestre)

The removal of important textile dyes by turnip peroxidase (TNP) was evaluated. The textile effluents besides the residual dyes contain also chemical auxiliaries such as salts, dispersing and wetting agents. The effect of these was evaluated in the removal of the dyes reactive blue 21 and reactive blue 19 by TNP in synthetic effluents. A decrease of the efficency decolorization was observed. The action of the enzyme on colour removal of dye mixture was equivalent to the dyes alone. The chemical demand of oxygen in the effluent after enzymatic treatment had a significant increase in relation to the untreated effluent.

Synthetic model of a new deoxybenzoin derivative from Deguelia hatschbachii A.M.G. Azevedo

In this paper we describe the synthesis of 2´,4´-dimethoxy-8-(propyl-2-one)-deoxybenzoin, a new compound employed as a model for the comparison with the respective spectral data for 6',4-dihydroxy-3'-(3,3- dimethylallyl)-2",2"-dimethylchromene(5",6":5',4')-2'-methoxy-8-(propyl-2-one) deoxybenzoin, recently isolated from Deguelia hatschbachii A.M.G. Azevedo. Both compounds have a "propyl-2-one" group attached to C-8 of the deoxybenzoin skeleton, for which there is no precedent in the literature. The Friedel-Crafts reaction of 1,3-dimethoxybenzene with phenylacetyl chloride furnished 2´,4´-dimethoxydeoxybenzoin, that after reaction with allyl bromide gave 2´,4´-dimethoxy-8-(allyl)-deoxybenzoin . Wacker oxidation gave the desired model compound in 15% overall yield. The corresponding spectral data reinforced the structure previously determined for the natural product.

Synthesis and characterization of activated carbon fibers from Kevlar

Kevlar [poly (p-phenilylene terephtalamide)], was used as a precursor in the preparation of activated carbon fibers. For this intention, physical and chemical activations were carried out. Activated fibers were physically prepared from the carbonization of the Kevlar and its later activation with CO2 and steam of water, by the other hand; the chemically activated fibers were obtained by means of the impregnation of the material with phosphoric acid and their later carbonization. Different conditions were used and preliminary analyses of the precursor were taken into account (TGA-DTA / IR). The resulting fibers were characterized by N2 (77K) adsorption, infrared spectroscopy, SEM, and immersion calorimetry. Yields and Burn off were also evaluated. The results shows that if you want to synthesize activated carbon fibers from Kevlar strong conditions respect to the commonly used such as water steam, high phosphoric acid concentrations and methods of impregnation are the ones who allows the development of optimal surface areas and pore volumes.