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1.
Neotrop Entomol ; 49(3): 337-346, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31940137

ABSTRACT

The present study investigated the occurrence of passalids in dead trunks with structural variations. Trunks were found in areas of white sand forests, locally known as Campinarana, in the state of Amazonas, Brazil. The collections were extended from May to December 2009. The mean diameter of the trunks and their stage of decomposition were classified, and the species of Passalidae were classified according to the location of their galleries. We used multiple generalized models to investigate the relationship between abundance and permutational multivariate analysis of variance (PERMANOVA) to investigate the relationships between predictors and passalid composition. A total of 361 passalids belonging to 13 species were collected from 11 tree species, of which Aldina heterophylla represented the highest proportion of logs (55%). Only the diameter of the trunk was related to the abundance of species, with trunks of larger diameters presented more individuals. The passalid composition was correlated with the diameter and decomposition of the trunks of all species of trees and only with the diameter of the trunks of A. heterophylla. Most of the species collected in Campinaranas construct their galleries in two or more regions of the trunk. The region that supported a greater number of colonies was the sapwood, followed by the inner bark and the soil-stem interface. The general habit of passalids found may be advantageous, probably to compensate for the low dispersion and isolation in areas with low availability of resources, such as Campinaranas forests in the Amazon.


Subject(s)
Coleoptera/classification , Trees/anatomy & histology , Animals , Forests , Plant Bark , Soil , Wood
3.
Int J Nanomedicine ; 14: 7975-7985, 2019.
Article in English | MEDLINE | ID: mdl-31632012

ABSTRACT

BACKGROUND: Multidrug-resistant bacteria such as extended-spectrum beta-lactamase (ESBL), Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus (MRSA) pose a challenge to the human health care system. MRSA is among the major causes of hospital-acquired and community infections. METHODS: Therefore, in the present study, we evaluated the antibacterial activity of silver nanoparticles synthesized by Fusarium oxysporum (AgNPbio) in combination with simvastatin against reference and multidrug-resistant bacterial strains. RESULTS: Simvastatin showed a minimal inhibitory concentration (MIC) ranging from 0.062 to 0.25 mg mL-1 against MRSA. AgNPbio with a size of 77.68± 33.95 nm and zeta potential -34.6 ± 12.7 mV showed an MIC of 0.212 mg mL-1 against S. aureus including MRSA strains. The checkerboard assay and time-kill curves exhibited a synergistic effect of the simvastatin-AgNPbio combination on antibacterial activity against MRSA strains. The combination of simvastatin and AgNPbio demonstrated antibacterial activity against Escherichia coli producing ESBL. Scanning electron microscopy showed the formation of cell surface protrusions after treatment with AgNPbio and the formation of a large amorphous mass after treatment with simvastatin, both in MRSA. CONCLUSION: Our results indicate that the combination of AgNPbio and simvastatin could be a great future alternative in the control of bacterial infections, where, when combined with simvastatin, smaller doses of AgNPbio are required, with the same antibacterial activity.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Escherichia coli/drug effects , Fusarium/metabolism , Metal Nanoparticles/chemistry , Methicillin-Resistant Staphylococcus aureus/drug effects , Silver/pharmacology , Simvastatin/pharmacology , Cell Death/drug effects , Drug Synergism , Erythrocytes/drug effects , Fusarium/drug effects , Fusarium/ultrastructure , Humans , Metal Nanoparticles/ultrastructure , Methicillin-Resistant Staphylococcus aureus/ultrastructure , Microbial Sensitivity Tests
5.
Braz. J. Biol. ; 79(4): 751-754, nov. 2019. tab
Article in English | VETINDEX | ID: vti-18040

ABSTRACT

The Neotropical migratory (piracema) fish species Brycon orbignyanus (Valenciennes, 1850), commonly known as piracanjuba, was once considered one of the most conspicuous resources for fisheries in the La Plata River Basin, the second largest in South America, but today is considered a threatened species, almost extinct in the wild ( Machado et al., 2008 ; Oliveira et al., 2017 ). It suffers from several pressures such as intense hydroelectric exploitation in the basin, pollution, deforestation of riverine vegetation and introduction of species ( Oliveira et al., 2017 ). Its omnivorous habits and fast growth curve under domestication ( Sipaúba-Tavares et al., 2008 ; Nogueira et al., 2014 ) makes this fish a good candidate for the development of aquaculture programs, which could guarantee its ex situ cultivation and help in situ conservation initiatives. Hatchery production of this species, targeting stocking efforts in areas affected by dam introduction, is presumed to be important in helping maintaining small population remnants in some isolated points in the basin, but this is still unaddressed in rigorous scientific studies. Such scenario brings about the importance of the development of tools for the rapid assessment of genetic diversity and structure, in order to identify the impacts over dwindling stocks and to evaluate the efficiency of fish stocking activities, in this important species.(AU)


Subject(s)
Animals , Characiformes/classification , Characiformes/microbiology
9.
Ticks Tick Borne Dis ; 4(6): 469-77, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24029695

ABSTRACT

One dimensional gel electrophoresis was used to separate proteins from the saliva of Rhipicephalus sanguineus female ticks fed on rabbits. Gel slices were subjected to tryptic digestion and analyzed by reversed-phase HPLC followed by MS/MS analysis. The data were compared to a database of salivary proteins of the same tick and to the predicted proteins of the host. Saliva was obtained by either pilocarpine or dopamine stimulation of partially fed ticks. Electrophoretic separations of both yielded products that were identified by mass spectrometry, although the pilocarpine-derived sample was of much better quality. The majority of identified proteins were of rabbit origin, indicating the recycling of the host proteins in the tick saliva, including hemoglobin, albumin, haptoglobin, transferring, and a plasma serpin. The few proteins found that were previously associated with parasitism and blood feeding include 2 glycine-rich, cement-like proteins, 2 lipocalins, and a thyropin protease inhibitor. Among other of the 19 tick proteins identified, albeit with undefined roles, were SPARC and cyclophilin A. This catalog provides a resource that can be mined for secreted molecules that play a role in tick-host interactions.


Subject(s)
Dopamine Agents/pharmacology , Dopamine/pharmacology , Muscarinic Agonists/pharmacology , Pilocarpine/pharmacology , Proteome/metabolism , Rhipicephalus sanguineus/metabolism , Animals , Arthropod Proteins/drug effects , Arthropod Proteins/metabolism , Chromatography, High Pressure Liquid , Female , Host-Parasite Interactions , Proteome/drug effects , Rabbits , Rhipicephalus sanguineus/drug effects , Saliva/metabolism , Tandem Mass Spectrometry
10.
Rev. bras. plantas med ; Rev. bras. plantas med;13(3): 293-297, 2011. tab
Article in English | LILACS | ID: lil-601035

ABSTRACT

The antibacterial effect of Lippia sidoides (rosemary pepper) essential oil was tested against the bacteria Staphylococcus aureus and Escherichia coli isolated from homemade Minas cheese produced in Brazil. The Minimum Inhibitory Concentration (MIC) determined in the Dilution Test was 13 µL oil mL-1 for both bacteria, which characterizes inhibitory action in broth for a 24-hour interaction period. The Minimum Bactericidal Concentration (MBC) determined in the Suspension Test, with one minute of contact, was 25 µL oil mL-1 for both tested bacteria, obtaining at this concentration a bactericidal effect of 99.9 percent on the viable bacterial cells from each sample. Results demonstrated the bacterial activity of Lippia sidoides essential oil against S. aureus and E. coli, suggesting its use as an antibacterial agent in foods.


O efeito antibacteriano do óleo essencial da Lippia sidoides (alecrim-pimenta) foi testado contra as bactérias Staphylococcus aureus e Escherichia coli isoladas de queijo minas artesanal, produzido no Brasil. A Concentração Inibitória Mínima (CIM) determinada por Teste de Diluição foi de 13 µL de óleo mL-1 para as duas bactérias, o que caracteriza ação inibitória em caldo durante vinte quatro horas de interação. A Concentração Bactericida Mínima (CBM) determinada através de Teste de Suspensão, com um minuto de contato, foi de 25 µL de óleo mL-1 para ambas as bactérias testadas, obtendo-se a esta concentração o efeito bactericida de 99,9 por cento sobre as células bacterianas viáveis em cada uma das amostras. Os resultados demonstraram atividade bactericida do óleo essencial de Lippia sidoides contra S. aureus e E. coli, sugerindo a possibilidade do uso como agente antibacteriano em alimentos.


Subject(s)
Anti-Bacterial Agents , Escherichia coli/immunology , Lippia , Oils, Volatile , Plants, Medicinal , Staphylococcus aureus/immunology , Brazil , Disk Diffusion Antimicrobial Tests , Cheese/analysis
11.
Vet Res Commun ; 31(8): 1037-45, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17285246

ABSTRACT

Feed contamination can lead to nutrient losses and detrimental effects on animal health and production. The purposes of this study were to investigate the mycobiota in equine mixed feeds and to determine natural contamination with aflatoxin B1 (AFB1) and fumonisin B1 (FB1). Fungal enumeration of equine feed samples was done. A commercially available enzyme-linked immunosorbent assay kit was applied to quantify AFB1 and FB1. A comparison between ELISA and HPLC was carried out. Feed mould counts ranged from <1 x 10(2) to 1 x 10(5) cfu/g. The most frequent genus isolated was Aspergillus (40.54%), followed by Penicillium (18.38%) and Fusarium (16.22%). The most prevalent Aspergillus sp. was A. flavus (36%). AFB1 values ranged between 0.01 and 99.4 microg/kg. FB(1) levels ranged between 0.01 and 7.49 microg/kg. HPLC and ELISA methods showed positive correlation for AFB1 and FB1 determinations (r = 0.9851 and r = 0.9791, respectively). The ELISA analytical method was efficient for AFB1 and FB1 detection. The scarcity of studies on natural fungal contamination and on the presence of AFB1 and FB1 in materials used as equine feed ingredients highlights the value and contribution of this study.


Subject(s)
Aflatoxin B1/analysis , Animal Feed/microbiology , Fumonisins/analysis , Horse Diseases/microbiology , Aflatoxin B1/poisoning , Animals , Aspergillus/isolation & purification , Aspergillus/metabolism , Chromatography, High Pressure Liquid/veterinary , Colony Count, Microbial/veterinary , Enzyme-Linked Immunosorbent Assay/veterinary , Fumonisins/poisoning , Fusarium/isolation & purification , Fusarium/metabolism , Horse Diseases/metabolism , Horses , Penicillium/isolation & purification , Penicillium/metabolism
12.
Lett Appl Microbiol ; 42(2): 179-84, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16441385

ABSTRACT

AIMS: The objective of this study was to determine the ochratoxin (OT) and aflatoxin (AF) production by three strains of Aspergillus spp. under different water activities, temperature and incubation time on barley rootlets (BR). METHODS AND RESULTS: Aspergillus ochraceus and Aspergillus flavus were able to produce mycotoxins on BR. Aspergillus ochraceus produced ochratoxin A (OTA) at 0.80 water activity (a(w)), at 25 and 30 degrees C as optimal environmental conditions. The OTA production varies at different incubation days depending on a(w). Aflatoxin B(1) (AFB1) accumulation was obtained at 25 degrees C, at 0.80 and 0.95 a(w), after 14 and 21 incubation days respectively. Temperature was a critical factor influencing OTA and AFB(1) production. CONCLUSIONS: This study demonstrates that BR support OTA and AFB(1) production at relatively low water activity (0.80 a(w)) and high temperatures (25-30 degrees C). SIGNIFICANCE AND IMPACT OF THE STUDY: The study of ecophysiological parameters and their interactions would determine the prevailing environmental factors, which enhance the mycotoxin production on BR used as animal feed.


Subject(s)
Aflatoxins/biosynthesis , Aspergillus/metabolism , Food Microbiology , Hordeum/microbiology , Mycotoxins/biosynthesis , Ochratoxins/biosynthesis , Water/metabolism , Aspergillus/growth & development , Temperature , Time Factors
13.
Vet Microbiol ; 113(1-2): 89-96, 2006 Mar 10.
Article in English | MEDLINE | ID: mdl-16309858

ABSTRACT

In Brazil, commercial feedstuffs are an important component in modern animal husbandry, but there is no information available about fungal contamination and ochratoxin A (OTA) production. The aims of this study were to determine the mycoflora incidence in poultry feeds and evaluate OTA production. In addition, the ability to produce OTA by several Aspergillus and Penicillium species was investigated. A total of 96 samples of poultry feeds were collected from four factories in Rio de Janeiro. Samples were examined for total moulds, for Aspergillus and Penicillium spp. occurrence and for their relative densities on dichloran rose bengal chloramphenicol and dichloran 18% glycerol media. The capacity to produce ochratoxin A by selected Aspergillus and Penicillium species was determined by HPLC. Total mould counts were generally higher than 1 x 10(5 )CFU ml(-1). Aspergillus and Penicillium species were isolated in the highest numbers. Aspergillus flovus and Penicillium citrinum were the most prevalent species. There was a high percentage of potential OTA producers (46%). The amount of OTA produced on this substrate was enough to cause adverse effects in animals. Several strains isolated from poultry feeds were able to produce high levels of OTA on chloramphenicol yeast medium. OTA in raw materials needs to be surveyed and storage practices must be investigated to determine occurrence and establish the livestock toxicological risk in poultry feed.


Subject(s)
Animal Feed/microbiology , Aspergillus/metabolism , Fungi/isolation & purification , Ochratoxins/biosynthesis , Penicillium/metabolism , Animals , Aspergillus/classification , Aspergillus/growth & development , Aspergillus/isolation & purification , Colony Count, Microbial/veterinary , Fungi/classification , Fungi/growth & development , Ochratoxins/analysis , Penicillium/classification , Penicillium/growth & development , Penicillium/isolation & purification , Poultry
14.
Insect Mol Biol ; 13(1): 73-88, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14728669

ABSTRACT

Anopheles (Nyssorhynchus) darlingi is an important malaria vector in South and Central America; however, little is known about molecular aspects of its biology. Genomic and proteomic analyses were performed on the salivary gland products of Anopheles darlingi. A total of 593 randomly selected, salivary gland-derived cDNAs were sequenced and assembled based on their similarities into 288 clusters. The putative translated proteins were classified into three categories: (S) secretory products, (H) housekeeping products and (U) products with unknown cell location and function. Ninety-three clusters encode putative secreted proteins and several of them, such as an anophelin, a thrombin inhibitor, apyrases and several new members of the D7 protein family, were identified as molecules involved in haematophagy. Sugar-feeding related enzymes (alpha-glucosidases and alpha-amylase) also were found among the secreted salivary products. Ninety-nine clusters encode housekeeping proteins associated with energy metabolism, protein synthesis, signal transduction and other cellular functions. Ninety-seven clusters encode proteins with no similarity with known proteins. Comparison of the sequence divergence of the S and H categories of proteins of An. darlingi and An. gambiae revealed that the salivary proteins are less conserved than the housekeeping proteins, and therefore are changing at a faster evolutionary rate. Tabular and supplementary material containing the cDNA sequences and annotations are available at http://www.ncbi.nlm.nih.gov/projects/Mosquito/A_darlingi_sialome/


Subject(s)
Anopheles/genetics , DNA, Complementary/classification , Gene Library , Saliva/chemistry , Salivary Glands/metabolism , Animals , Brazil , Databases, Genetic , Electrophoresis, Polyacrylamide Gel , Sequence Analysis, DNA
15.
J Microsc ; 213(2): 94-100, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14731290

ABSTRACT

There is great demand for the development of composite materials containing small metal or metal oxides particles, owing to their variable properties and wide application. However, microscopic evaluation of these materials using high-vacuum scanning electron microscopy is difficult because the samples must undergo a series of preparation steps to reach a high image quality and to avoid becoming shrunk inside the microscope vacuum chamber. Thus, in this study, we used variable pressure scanning electron microscopy to evaluate the morphology and iron distribution on the surface of magnetic microspheres based on poly(styrene-co-divinylbenzene). These materials were obtained by suspension copolymerization of styrene and divinylbenzene in the presence of fine iron particles. Energy-dispersive X-rays were also used to analyse distribution of the iron particles. The results indicate that, under the conditions used, magnetic microspheres with a relatively narrow size distribution were formed. Moreover, the micrographs show that agglomerated iron particles appeared only on the microsphere surface.

16.
Cad Saude Publica ; 17(3): 705-12, 2001.
Article in English | MEDLINE | ID: mdl-11395807

ABSTRACT

The article analyzes the World Health Organization Report for 2000, with emphasis placed on the methodology used to analyze the indicators utilized to compare and classify the performance of the health systems of the 191 member countries. The Report's contribution was the compromise of monitoring the performance of the health systems of member countries, but because of the inconsistent way it was elaborated, and the utilization of questionable scientific evaluation methodologies, the Report fails to give a clear picture. A criterion-based methodology revision is imposed. The main problems in evidence are the choice of individual indicators of disparity in health that discount the population profile, the inadequate control of the impact of social disparities over the performance of the systems, the evaluation of the responsibility of systems that are only partially articulated to the right of the citizens, the lack of data for a great number of countries, consequently having inconsistent estimations, and the lack of transparency in the methodological procedures in the calculation of some indicators. The article suggests a wide methodological revision of the Report.


Subject(s)
Annual Reports as Topic , Health Services , Quality of Health Care , World Health Organization , Female , Health Status Indicators , Humans , Male
18.
Am J Trop Med Hyg ; 62(6): 740-5, 2000 Jun.
Article in English | MEDLINE | ID: mdl-11304066

ABSTRACT

Antibody (IgG) responses to salivary gland homogenate and to a recombinant salivary protein from the sand fly Lutzomyia longipalpis were investigated using sera from children living in an endemic area of visceral leishmaniasis in Brazil. We classified children into four groups according to their responses to Leishmania antigen: (Group I) positive serology and positive delayed type hypersensitivity (DTH), (Group II) positive serology and negative DTH, (Group III) negative serology and positive DTH, and (Group IV) negative serology and negative DTH. A highly significant correlation was found between anti-salivary gland IgG levels and DTH responses. An L. longipalpis salivary recombinant protein used as an antigen in an enzyme-linked immuno sorbent assay (ELISA) gave a significant but different result. A positive correlation was found between anti-Leishmania IgG and anti-recombinant protein IgG titers. The results indicate that sand fly salivary proteins may be of relevance to the study the epidemiology of leishmaniasis.


Subject(s)
Antibodies/blood , Antigens/immunology , Leishmaniasis, Visceral/epidemiology , Psychodidae/immunology , Salivary Proteins and Peptides/immunology , Animals , Antibodies/immunology , Blotting, Western , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay/methods , Humans , Hypersensitivity, Delayed , Immunoglobulin G/blood , Immunoglobulin G/immunology , Leishmaniasis, Visceral/immunology , Protozoan Proteins/immunology , Recombinant Proteins/immunology , Salivary Glands/immunology , Salivary Proteins and Peptides/genetics
20.
J Biol Chem ; 270(18): 10893-6, 1995 May 05.
Article in English | MEDLINE | ID: mdl-7738029

ABSTRACT

Heme in aqueous solutions actively promotes free radical reactions leading to degradation of biological molecules. The blood-sucking insect Rhodnius prolixus has a heme-binding protein (RHBP) in its hemolymph (Oliveira, P.L., Kawooya, J.K., Ribeiro, J.M.C., Meyer, T., Poorman, R., Alves, E.W., Walker, F., Padovan, G.J., and Masuda, H. (1994) J. Biol. Chem. 270, 10897-10901. Here we show that this protein inhibits heme-dependent peroxidation of both linolenic acid liposomes and lipophorin, the main lipoprotein of insect hemolymph. The oxidized lipophorin is functionally impaired, being defective both in its capacity to be loaded with phospholipids from the fat body as well as in its ability to deliver phospholipids to the growing oocytes. RHBP prevents the heme-induced oxidative damage to lipophorin. It is proposed that in vivo RHBP binds the heme derived from digestion of blood hemoglobin, suppressing the generation of activated oxygen species and protecting the insect against oxidative stress throughout the feeding cycle.


Subject(s)
Carrier Proteins/metabolism , Hemeproteins/metabolism , Lipid Peroxides/metabolism , Lipoproteins , Rhodnius/chemistry , Adipose Tissue/metabolism , Animals , Antioxidants , Female , Heme-Binding Proteins , Hemolymph/chemistry , Ovary/metabolism , Oxidation-Reduction , Phospholipids/metabolism , Rhodnius/metabolism
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