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1.
PLoS One ; 19(5): e0303976, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820537

RESUMO

The blaNDM-1 gene and its variants encode metallo-beta-lactamases that confer resistance to almost all beta-lactam antibiotics. Genes encoding blaNDM-1 and its variants can be found in several Acinetobacter species, and they are usually linked to two different plasmid clades. The plasmids in one of these clades contain a gene encoding a Rep protein of the Rep_3 superfamily. The other clade consists of medium-sized plasmids in which the gene (s) involved in plasmid replication initiation (rep)have not yet been identified. In the present study, we identified the minimal replication region of a blaNDM-1-carrying plasmid of Acinetobacter haemolyticus AN54 (pAhaeAN54e), a member of this second clade. This region of 834 paired bases encodes three small peptides, all of which have roles in plasmid maintenance. The plasmids containing this minimal replication region are closely related; almost all contain blaNDM genes, and they are found in multiple Acinetobacter species, including A. baumannii. None of these plasmids contain an annotated Rep gene, suggesting that their replication relies on the minimal replication region that they share with the plasmid pAhaeAN54e. These observations suggest that this plasmid lineage plays a crucial role in the dissemination of the blaNDM-1 gene and its variants.


Assuntos
Acinetobacter , Plasmídeos , Origem de Replicação , beta-Lactamases , beta-Lactamases/genética , Plasmídeos/genética , Acinetobacter/genética , Acinetobacter/efeitos dos fármacos , Origem de Replicação/genética , Replicação do DNA/genética , Proteínas de Bactérias/genética
2.
PLoS One ; 19(1): e0297010, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38277370

RESUMO

Proteins are biological units whose essence is defined by their functional relationships with other proteins or biomolecules such as RNA, DNA, lipids, or carbohydrates. These functions encompass enzymatic, structural, regulatory, or physical interaction roles. The STRING database (Nucleic Acids Research, 8 Jan 2021;49(D1): D605-12) provides an index that defines the functional interaction networks between proteins in model organisms. To facilitate the identification, visualization, and evaluation of potential functional networks across organisms from different phylogenetic lineages, we have developed PhyloString (https://biocomputo.ibt.unam.mx/phylostring/), a web server that utilizes the indices of the STRING database. PhyloString decomposes these functional networks into modules, representing cohesive units of proteins grouped based on their similarity of STRING values and the phylogenetic origins of their respective organisms. This study presents and thoroughly discusses examples of such functional networks and their modules identified using PhyloString.


Assuntos
Proteínas , Software , Filogenia , Proteínas/química , Computadores , RNA/química , Internet
3.
Sensors (Basel) ; 23(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37631770

RESUMO

The concept of cognitive radio (CR) as a tool to optimize the obstacle of spectral coexistence has promoted the development of shared satellite-terrestrial wireless networks. Nevertheless, in some applications like Earth Exploration Satellite Services, which demand high spectral efficiency (bps/Hz) for downlink transmissions, spectral coexistence amidst interferences from cellular Base Stations is still challenging. Our research aims to mitigate these interferences on low-orbit satellite downlinks carrying imaging data received from a ground station. In order to fulfill this, we present cognitive radio approaches to enhance spectrum exploitation and introduce the adaptive modulation and coding (MODCOD) technique to increase RF power and spectral efficiencies. Therefore, we propose a combined methodology using CR and adaptive MODCOD (ACM) techniques. Afterwards, we applied the solution by monitoring the signal to interference plus noise ratio and the MODCOD strategy. Finally, we provide a real in situ case study at the Cuiabá ground station located in Brazil's central area, which receives images from an Earth observation satellite (EOS). In addition to demonstrating the strategy effectiveness in this scenario, we conducted a bench test emulating the interfering wireless communication system. In this sense, we demonstrated the proposed approach, successfully mitigating the harmful effects on the received EOS images.

4.
PLoS One ; 18(5): e0285201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37141209

RESUMO

One of the main characteristics of prokaryotic genomes is the ratio in which guanine-cytosine bases are used in their DNA sequences. This is known as the genomic GC content and varies widely, from values below 20% to values greater than 74%. It has been demonstrated that the genomic GC content varies in accordance with the phylogenetic distribution of organisms and influences the amino acid composition of their corresponding proteomes. This bias is particularly important for amino acids that are coded by GC content-rich codons such as alanine, glycine, and proline, as well as amino acids that are coded by AT-rich codons, such as lysine, asparagine, and isoleucine. In our study, we extend these results by considering the effect of the genomic GC content on the secondary structure of proteins. On a set of 192 representative prokaryotic genomes and proteome sequences, we identified through a bioinformatic study that the composition of the secondary structures of the proteomes varies in relation to the genomic GC content; random coils increase as the genomic GC content increases, while alpha-helices and beta-sheets present an inverse relationship. In addition, we found that the tendency of an amino acid to form part of a secondary structure of proteins is not ubiquitous, as previously expected, but varies according to the genomic GC content. Finally, we discovered that for some specific groups of orthologous proteins, the GC content of genes biases the composition of secondary structures of the proteins for which they code.


Assuntos
Aminoácidos , Proteoma , Composição de Bases , Proteoma/genética , Filogenia , Aminoácidos/química , Genômica , Códon/genética
5.
Med Vet Entomol ; 37(2): 316-329, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36543747

RESUMO

Triatoma maculata (Hemiptera, Reduviidae, Triatominae) occurs across dry-to-semiarid ecoregions of northern South America, where it transmits Trypanosoma cruzi, causative agent of Chagas disease. Using 207 field-caught specimens from throughout the species' range, mitochondrial(mt) DNA sequence data, and cytogenetics, we investigated inter-population genetic diversity and the phylogenetic affinities of T. maculata. Mitochondrial DNA sequence analyses (cytb and nd4) disclosed a monophyletic T. maculata clade encompassing three distinct geographic groups: Roraima formation (Guiana shield), Orinoco basin, and Magdalena basin (trans-Andean). Between-group cytb distances (11.0-12.8%) were larger than the ~7.5% expected for sister Triatoma species; the most recent common ancestor of these T. maculata groups may date back to the late Miocene. C-heterochromatin distribution and the sex-chromosome location of 45S ribosomal DNA clusters both distinguished Roraima bugs from Orinoco and Magdalena specimens. Cytb genealogies reinforced that T. maculata is not sister to Triatoma pseudomaculata and probably represents an early (middle-late Miocene) offshoot of the 'South American Triatomini lineage'. In sum, we report extensive genetic diversity and deep phylogeographic structuring in T. maculata, suggesting that it may consist of a complex of at least three sibling taxa. These findings have implications for the systematics, population biology, and perhaps medical relevance of T. maculata sensu lato.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Animais , Triatoma/genética , Filogenia , Doença de Chagas/veterinária , Trypanosoma cruzi/genética , DNA Mitocondrial/genética , Análise Citogenética/veterinária
6.
Biotechnol Appl Biochem ; 70(3): 1001-1014, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36380682

RESUMO

Silver nanoparticles (AgNPs) synthesized from green synthesis using medicinal plants are presented as an option for the development of new antimicrobial agents. In this context, this study aims to evaluate the antimicrobial activity of silver nanoparticles synthesized from the aqueous extract of Schinus terebinthifolius Raddi leaves, popularly known as "aroeira." A 23 factorial design was used to assess the statistical significance of the studied factors, and Box-Behnken design was used to define the optimal conditions for the green synthesis of AgNPs. The studied factors were significant for the synthesis of nanoparticles, and the optimal conditions were pH 9.5, reaction time of 180 min, and 10 g of S. terebinthifolius Raddi leaves. The samples were characterized using UV-Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and dynamic light scattering. Antimicrobial activity was evaluated using the broth microdilution method and through the minimum microbicidal concentration. AgNPs showed greater antimicrobial efficacy compared to the extract, both for bacteria and fungi: bacteriostatic activity against all tested bacteria and bactericidal against Pseudomonas aeruginosa, besides fungistatic action against Candida albicans and Candida glabrata. Finally, the aqueous extract of "aroeira" leaves was effective in the synthesis of AgNPs, with greater antimicrobial potential than the extract.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Schinus , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Candida albicans , Espectroscopia de Infravermelho com Transformada de Fourier , Folhas de Planta/química , Testes de Sensibilidade Microbiana , Difração de Raios X
7.
Mem Inst Oswaldo Cruz ; 117: e210130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830010

RESUMO

Chagas disease (CD) still imposes a heavy burden on most Latin American countries. Vector-borne and mother-to-child transmission cause several thousand new infections per year, and at least 5 million people carry Trypanosoma cruzi. Access to diagnosis and medical care, however, is far from universal. Starting in the 1990s, CD-endemic countries and the Pan American Health Organization-World Health Organization (PAHO-WHO) launched a series of multinational initiatives for CD control-surveillance. An overview of the initiatives' aims, achievements, and challenges reveals some key common themes that we discuss here in the context of the WHO 2030 goals for CD. Transmission of T. cruzi via blood transfusion and organ transplantation is effectively under control. T. cruzi, however, is a zoonotic pathogen with 100+ vector species widely spread across the Americas; interrupting vector-borne transmission seems therefore unfeasible. Stronger surveillance systems are, and will continue to be, needed to monitor and control CD. Prevention of vertical transmission demands boosting current efforts to screen pregnant and childbearing-aged women. Finally, integral patient care is a critical unmet need in most countries. The decades-long experience of the initiatives, in sum, hints at the practical impossibility of interrupting vector-borne T. cruzi transmission in the Americas. The concept of disease control seems to provide a more realistic description of what can in effect be achieved by 2030.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Idoso , América/epidemiologia , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Vetores de Doenças , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez
8.
An Acad Bras Cienc ; 94(4): e20201735, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830071

RESUMO

The environmental and health risks associated with the application of synthetic chemical inputs in agriculture increased the demand for technologies that allow higher performance and quality of vegetable crops by implementing synergistic materials with the principles of sustainability. In this work, the seed coating with the biomass of Dunaliella salina incorporated in a bioplastic film of Manihot esculenta (cassava) was evaluated as an initial growth and secondary compounds stimulator of Coriandrum sativum (coriander) plants. The obtained results demonstrated that the coating stimulated an increase in the germination percentage (28.75%) and also in concentration of bioactive compounds, such as the six-fold increment of caffeic acid (13.33 mg 100 g-1). The carbohydrates, lipids, and proteins present in the microalgae biomass seem to be responsible for these increments once they are known for providing energy to the seedling development and coordinating the secondary metabolites synthesis. As conclusion, we consider the coating with biomass of D. salina an alternative for crop improvement that contributes to the development of sustainable agricultural practices.


Assuntos
Biomassa , Clorofíceas , Coriandrum , Microalgas , Desenvolvimento Vegetal , Metabolismo Secundário , Sementes , Ácidos Cafeicos , Carboidratos , Clorofíceas/química , Coriandrum/química , Coriandrum/efeitos dos fármacos , Coriandrum/crescimento & desenvolvimento , Coriandrum/metabolismo , Produção Agrícola/métodos , Lipídeos , Manihot/química , Microalgas/química , Desenvolvimento Vegetal/efeitos dos fármacos , Metabolismo Secundário/efeitos dos fármacos , Sementes/química , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Desenvolvimento Sustentável
9.
Artigo em Inglês | MEDLINE | ID: mdl-35627883

RESUMO

The state of Pará has recorded seven Leishmania species that cause tegumentary leishmaniasis (TL). Leishmania species induce distinct immunological responses from the host and exhibit resistance to Glucantime, the first-line drug treatment for TL in Brazil. OBJECTIVE: Identify the etiology of TL in an Amazonian city in the state of Pará. MATERIAL AND METHODS: Eleven patients with TL were recruited and nasal swabs, lesion swabs, and skin fragments samples were collected. In the control group (n = 6), only the nasal swabs were collected. Polymerase Chain Reaction (PCR) amplification of the gene region hsp70-234 was performed using the extracted DNA from the samples, from which nine patients with TL and five in the control group were positive. Products were sequenced, mounted in CAP3 software, aligned using MAFFT v.7.221, edited in Geneious software v.8.1.7, and compared and aligned with sequences available in GenBank using the BLAST tool. RESULTS: For patients with TL, six molecular diagnosis at the species level (L. (Viannia) braziliensis (n = 5/9), L. (Viannia) shawi (n = 1/9)) and three at the genus level (Leishmania sp. (n = 3/9)) were obtained. In the control group, four individuals were infected with Leishmania sp. (n = 4/5) and L. (V.) shawi (n = 1/5). CONCLUSION: This is the first report of L. (V.) shawi infection in the mucosal secretion of a healthy person in Brazil. Moreover, genetic variants were identified in the haplotypes of L. (V.) braziliensis in the gene sequence hsp70-234.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Brasil , Humanos , Leishmania/genética , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Reação em Cadeia da Polimerase
10.
Sci Rep ; 12(1): 5022, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35322088

RESUMO

The perturbative integral method was applied to quantify the contribution of external forces during a specific interval of time in trajectories of spacecraft around asteroids and under the Luni-solar influence. However, this method has not been used to quantify the contributions of drag in aerocapture and aerobraking. For this reason, the planet Mars is selected to apply this method during an aerogravity-assisted maneuver. Several trajectories are analyzed, making use of a drag device with area to mass ratios varying from 0.0 to 20.0 m2/kg, simulating solar sails or de-orbit devices. The mathematical model is based in the restricted three-body problem. The use of this maneuver makes it possible to obtain the variations of energy in the trajectory, replacing expensive maneuvers based on fuel consumption. To observe the effects of the maneuvers, different values of pericenter velocity and altitude were selected for prograde and retrograde orbits. The innovation of this research is the application of an integral method to quantify the delta-V of the aero gravity maneuver, comparing the cost of the maneuver with the traditional methods of space propulsion. The results allow the identification of orbits with conditions to capture, and the perturbative maps show the velocity variations.


Assuntos
Marte , Voo Espacial , Gravitação , Modelos Teóricos , Astronave
11.
Coron Artery Dis ; 33(6): 456-464, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35190516

RESUMO

INTRODUCTION: Acute coronary syndrome (ACS) is less frequent in young adults, but it has become a significant health problem, associated with the increasing prevalence of modifiable risk factors. OBJECTIVES: To characterize patients admitted with premature ACS, comparing with those with nonpremature ACS. METHODS: We performed a retrospective study encompassing patients of the Portuguese Registry (ProACS), comparing two groups: one composed of men less than 55 and women less than 65 years old; and other with men ≥55 and women ≥65 years old at the ACS admission. The primary endpoint was the composite of in-hospital mortality, stroke and myocardial reinfarction (re-MI). RESULTS: A total of 29 870 patients were enrolled and 25% had premature ACS, with a mean age of 50 ± 7 years old. They had a larger prevalence of smoking habits, obesity and dyslipidemia. ST-segment elevation MI (STEMI) was the main admission diagnosis in young patients and coronary angiogram mainly revealed one vessel disease in this subgroup. They had a lower Killip-Kimball (KK) class and mostly preserved left ventricular ejection fraction (LVEF). Composite endpoint was more frequent in nonpremature ACS patients. Nonpremature age, presentation with syncope or cardiac arrest, KK class >1, multivessel disease and LVEF <40% were independent predictors of the primary endpoint ( P < 0.001). Younger patients had lower rates of in-hospital all-cause mortality, re-MI and stroke. One-year all-cause mortality and 1-year cardiovascular and non-cardiovascular readmissions were also lower. CONCLUSIONS: Premature ACS affects 25% of the ACS population, mostly presenting with STEMI, but generally associated with better clinical evolution. Nevertheless, prevention measures are essential to correct modifiable cardiovascular risk factors and reduce coronary events.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio com Supradesnível do Segmento ST , Acidente Vascular Cerebral , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/terapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Acidente Vascular Cerebral/epidemiologia , Volume Sistólico , Função Ventricular Esquerda
12.
Food Chem ; 369: 130672, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34450513

RESUMO

In this study, mineral composition, centesimal composition and lead were evaluated in pine nut seeds (raw and cooked) from five Brazilian states. Mineral composition was determined by ICP OES and lead by GF AAS. The results for minerals were evaluated by Boxplot, PCA and HCA, using the R software. Average minerals in raw and cooked samples (mg 100 g-1) were: 15.2 and 10.8 (Ca), 0.168 and 0.113 (Cu), 0.506 and 0.330 (Fe), 536 and 420 (K), 51.3 and 40.6 (Mg), 0.373 and 0.208 (Mn), 132 and 102 (P) and 0.746 and 0.520 (Zn). The average centesimal composition (raw and cooked) was: 53.5 and 47.2% (moisture), 1.76 and 1.26% (ash), 3.90 and 3.53% (protein), 40.8 and 48.0% (carbohydrate) and 179 and 206 kcal/100 g (total caloric value) and Pb was not detected. The chemometric analysis showed a distinction of raw and cooked samples due to significant nutrient losses after thermal processing.


Assuntos
Araucaria , Nozes , Análise de Dados , Minerais , Sementes
13.
Mem. Inst. Oswaldo Cruz ; 117: e210130, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1386360

RESUMO

Chagas disease (CD) still imposes a heavy burden on most Latin American countries. Vector-borne and mother-to-child transmission cause several thousand new infections per year, and at least 5 million people carry Trypanosoma cruzi. Access to diagnosis and medical care, however, is far from universal. Starting in the 1990s, CD-endemic countries and the Pan American Health Organization-World Health Organization (PAHO-WHO) launched a series of multinational initiatives for CD control-surveillance. An overview of the initiatives' aims, achievements, and challenges reveals some key common themes that we discuss here in the context of the WHO 2030 goals for CD. Transmission of T. cruzi via blood transfusion and organ transplantation is effectively under control. T. cruzi, however, is a zoonotic pathogen with 100+ vector species widely spread across the Americas; interrupting vector-borne transmission seems therefore unfeasible. Stronger surveillance systems are, and will continue to be, needed to monitor and control CD. Prevention of vertical transmission demands boosting current efforts to screen pregnant and childbearing-aged women. Finally, integral patient care is a critical unmet need in most countries. The decades-long experience of the initiatives, in sum, hints at the practical impossibility of interrupting vector-borne T. cruzi transmission in the Americas. The concept of disease control seems to provide a more realistic description of what can in effect be achieved by 2030.

14.
Food Chem ; 365: 130477, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34237570

RESUMO

The contamination of milk by antibiotic residues is a worldwide health and food safety problem. There is a need to develop new methods for the rapid determination of antibiotic residues in milk. A method has been developed for determining tylosin residues directly in powdered milk using Fourier Transformed Infrared spectroscopy (FTIR). Tylosin is a broad-spectrum macrolide antibiotic. The spectra obtained were submitted to chemometric analysis to obtain a prediction model for tylosin concentration in powdered milk. Using the Boruta algorithm, the absorption bands related to the milk contamination by the antibiotic were identified. Random forest was shown to be adequate for the prediction of tylosin residues in milk at low concentrations (≤ 100 µg L-1) and the prediction model generated showed high correlation and determination coefficients (greater than 0.95). The proposed methodology proved to be efficient for the investigation of antibiotic residues in powdered milk.


Assuntos
Leite , Tilosina , Animais , Antibacterianos/análise , Leite/química , Pós , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Tilosina/análise
15.
Food Chem ; 363: 129995, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34144423

RESUMO

Unconventional edible plants (UEP) are potential supplementary sources of minerals and bioactive compounds. However, there is still a gap in the literature on UEP composition. In this study, the multielement/proximate composition of ten UEP from Brazil was evaluated by ICP OES. Furthermore, phenolic bioactives were quantified by HPLC-UV-DAD. The UEP showed high moisture content (84.85-95.27%) and elements (in mg Kg-1): Al (122-657), Ca (145-14,229), Cu (8.3-18.81), Fe (177-586), K (12.46-34.50%), Mg (157-1,552), Mn (16.85-84.96), Na (1,107-23,775), P (2,535-6,127), Si (189-1,695), Sr (25.56-104.63) and Zn (0.3-72.31). Nine phenolic bioactive compounds (1-2,147) and three flavonoids (1-2,042 mg Kg-1) were determined. PCA and HCA grouped samples (Java ginseng, Coriander, Spearmint and Indian borage) rich in minerals. Spearmint showed high levels of transcinamic acid, kaempferol and quercetin. This study contributes to the scientific development and use of UEP.


Assuntos
Oligoelementos , Brasil , Minerais , Análise Multivariada , Plantas Comestíveis , Oligoelementos/análise
16.
Food Chem ; 362: 130176, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111692

RESUMO

In the present work, multivariate designs were used to optimize an alkaline dissolution, assisted by ultrasound energy, procedure of goat meat using tetramethylammonium hydroxide (TMAH) aiming to determine Ca, Cu, Fe, K, Mg, Na and Zn by flame atomic absorption (FAAS) and emission (FAES) spectrometry. The optimal conditions found for the dissolution were in the following ranges: 0.4-0.5 g for the sample mass, 12-15 min of sonication and using 700-1000 µL of 25% TMAH at a temperature of 50 °C. The obtained limits of quantification varied between 0.221 (Mg) and 7.60 (Ca) µg g-1. Accuracy was assessed by comparing the results obtained by applying the proposed method with the digestion in an acid medium using a digesting block and by analyzing bovine liver certified reference material. The application of a t-test revealed that, at a 95% confidence level, there were no significant differences between the values obtained.


Assuntos
Análise de Alimentos/métodos , Carne/análise , Metais/análise , Espectrofotometria Atômica/métodos , Animais , Análise de Alimentos/estatística & dados numéricos , Cabras , Análise Multivariada , Compostos de Amônio Quaternário/química , Solubilidade , Espectrofotometria Atômica/estatística & dados numéricos , Temperatura
17.
PLoS One ; 16(5): e0252071, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34015050

RESUMO

Attalea palms provide primary habitat to Rhodnius spp., vectors of Trypanosoma cruzi. Flying from palms, these blood-sucking bugs often invade houses and can infect people directly or via food contamination. Chagas disease (CD) risk may therefore increase when Attalea palms thrive near houses. For example, Attalea dominate many deforested landscapes of eastern Amazonia, where acute-CD outbreaks are disturbingly frequent. Despite this possible link between deforestation and CD risk, the population-level responses of Amazonian Attalea and their resident Rhodnius to anthropogenic landscape disturbance remain largely uncharted. We studied adult Attalea palms in old-growth forest (OGF), young secondary forest (YSF), and cattle pasture (CP) in two localities of eastern Amazonia. We recorded 1856 Attalea along 10 transects (153.6 ha), and detected infestation by Rhodnius spp. in 18 of 280 systematically-sampled palms (33 bugs caught). Distance-sampling models suggest that, relative to OGF, adult Attalea density declined by 70-80% in CP and then recovered in YSF. Site-occupancy models estimate a strong positive effect of deforestation on palm-infestation odds (ßCP-infestation = 4.82±1.14 SE), with a moderate decline in recovering YSF (ßYSF-infestation = 2.66±1.10 SE). Similarly, N-mixture models suggest that, relative to OGF, mean vector density sharply increased in CP palms (ßCP-density = 3.20±0.62 SE) and then tapered in YSF (ßYSF-density = 1.61±0.76 SE). Together, these results indicate that disturbed landscapes may support between ~2.5 (YSF) and ~5.1 (CP) times more Attalea-dwelling Rhodnius spp. per unit area than OGF. We provide evidence that deforestation may favor palm-dwelling CD vectors in eastern Amazonia. Importantly, our landscape-disturbance effect estimates explicitly take account of (i) imperfect palm and bug detection and (ii) the uncertainties about infestation and vector density arising from sparse bug data. These results suggest that incorporating landscape-disturbance metrics into the spatial stratification of transmission risk could help enhance CD surveillance and prevention in Amazonia.


Assuntos
Doença de Chagas/parasitologia , Insetos Vetores/parasitologia , Rhodnius/patogenicidade , Trypanosoma cruzi/patogenicidade , Animais , Ecossistema
18.
PLoS One ; 16(3): e0246651, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33651833

RESUMO

Engulfment requires the coordinated, targeted synthesis and degradation of peptidoglycan at the leading edge of the engulfing membrane to allow the mother cell to completely engulf the forespore. Proteins such as the DMP and Q:AH complexes in Bacillus subtilis are essential for engulfment, as are a set of accessory proteins including GerM and SpoIIB, among others. Experimental and bioinformatic studies of these proteins in bacteria distinct from Bacillus subtilis indicate that fundamental differences exist regarding the organization and mechanisms used to successfully perform engulfment. As a consequence, the distribution and prevalence of the proteins involved in engulfment and other proteins that participate in different sporulation stages have been studied using bioinformatic approaches. These works are based on the prediction of orthologs in the genomes of representative Firmicutes and have been helpful in tracing hypotheses about the origin and evolution of sporulation genes, some of which have been postulated as sporulation signatures. To date, an extensive study of these signatures outside of the representative Firmicutes is not available. Here, we asked whether phyletic profiles of proteins involved in engulfment can be used as signatures able to describe the sporulation phenotype. We tested this hypothesis in a set of 954 Firmicutes, finding preserved phyletic profiles defining signatures at the genus level. Finally, a phylogenetic reconstruction based on non-redundant phyletic profiles at the family level shows the non-monophyletic origin of these proteins due to gain/loss events along the phylum Firmicutes.


Assuntos
Membrana Celular/metabolismo , Membrana Celular/microbiologia , Genômica , Peptidoglicano/metabolismo , Bacillus subtilis/genética , Parede Celular/metabolismo , Esporos Bacterianos/genética
19.
São Paulo; s.n; 2021. 164 p.
Tese em Português | LILACS | ID: biblio-1362209

RESUMO

As roupas constituem, em parte, a maneira como as pessoas vivem e expressam as necessidades humanas que avançam vorazmente sobre o sistema natural. Sob forma de vestuário, é possível visualizar a representatividade da cadeia têxtil no cotidiano das pessoas, os efeitos e influência da produção, consumo e descarte na sociedade. Do montante produzido anualmente, menos de 1% desses materiais são reciclados em novas roupas ou outros produtos. O setor têxtil é intensivo na extração de recursos e geração de resíduos, possui altos índices de desperdício e é extremamente poluidor. O Brasil possui a quinta maior cadeia têxtil do mundo. A economia circular e a economia criativa podem contribuir neste enfrentamento pelo seu potencial de promover a reutilização de recursos existentes e a redução de impactos sociais, ambientais e à saúde. Nesse contexto, o objetivo deste estudo é analisar empresas da cadeia têxtil que adotam princípios da economia criativa e da economia circular com o intuito de identificar práticas que minimizam os impactos ambientais de resíduos têxteis e expandem a consciência ambiental de consumidores e empresas. A partir da revisão bibliográfica sistemática e das informações obtidas em visitas técnicas, com observação de campo e registro fotográfico, assim como de entrevistas com base em roteiro pré-elaborado com os empreendedores, foi possível observar os princípios da economia circular e da economia criativa como diferencial estratégico do negócio. Foram identificados alguns marcadores que alicerçam as práticas sustentáveis desenvolvidas nos negócios analisados como: i) gestão da parceria e alinhamento de propósito; ii) Gestão do ciclo de vida ou associação aos fluxos de resíduos dos grandes geradores; iii) Logística reversa e a estruturação de custos para sua viabilidade. O estudo de caso evidenciou como diferentes domínios de conhecimento inter-relacionam os temas de economia criativa e economia circular de forma hierárquica. Assim, foi elaborado framework de planejamento estratégico e os dados levantados durante a pesquisa foram organizados em website, consolidando imagens e conceitos para divulgação da pesquisa, e apoiar empreendedores na concepção de novos negócios cujo propósito é a sustentabilidade.


Clothes constitute, in part, the way in which people live and express human needs that voraciously advance over the natural system. In the form of clothing, it is possible to visualize the representativeness of the textile chain in peoples daily lives, the effects and influence of production, consumption and disposal in society. Of the amount produced annually, less than 1% of these materials are recycled into new clothes or other products. The textile sector is intensive in resource extraction and waste production, has high levels of waste and is extremely polluting. Brazil has the fifth largest textile chain in the world. The circular economy and the creative economy can contribute to this confrontation by their potential to promote the reuse of existing resources and the reduction of social, environmental and health impacts. In this context, the objective of this study is to analyze companies in the textile chain that adopt principles of the creative economy and the circular economy in order to identify practices that minimize the environmental impacts of textile waste and expand the environmental awareness of consumers and companies. From the systematic bibliographic review and the information obtained in technical visits, with field observation and photographic record, as well as interviews based on a pre-prepared script with the entrepreneurs, it was possible to observe the principles of circular economy and creative economy as strategic differential of the business. Some markers were identified that underpin the sustainable practices developed in the analyzed businesses, such as: i) management of the partnership and alignment of purpose; ii) Life cycle management or association with waste streams from large generators; iii) Reverse logistics and cost structuring for its viability. The case study showed how different domains of knowledge interrelate the themes of creative economy and circular economy in a hierarchical way. Thus, a strategic planning framework was developed and the data collected during the research were organized on a website, consolidating images and concepts for disseminating the research, and supporting entrepreneurs in the conception of new businesses whose purpose is sustainability.


Assuntos
Indústria Têxtil , Têxteis , Vestuário , Gerenciamento de Resíduos , Desenho , Economia
20.
Artigo em Inglês | MEDLINE | ID: mdl-33207754

RESUMO

The American cutaneous (CL) and visceral leishmaniasis (VL) are zooanthroponoses transmitted by sand flies. Brazil records thousands of human leishmaniasis cases annually. Dogs are reservoirs of Leishmania infantum, which causes VL, but their role in the transmission cycle of CL is debatable. Wild mammals are considered reservoirs of the aetiological agents of CL (Leishmania spp.). OBJECTIVE: To describe the aetiology of leishmaniasis in dogs in an endemic area for CL and VL in the Amazon, Brazil. METHODS: Clinical evaluation and blood collection of 40 dogs from the villages Ubim (20) and Socorro (20), city of Tomé-Açu, state of Pará, were carried out. The DNA extracted from the blood was used for PCR with Leishmania-specific primers targeting the hsp70-234 gene sequence. Products were sequenced (ABI3500XL), and the sequences were aligned, edited (BioEdit), and analyzed (Blastn). RESULTS: Of the 34 amplified samples, 21 were sequenced, namely Leishmania infantum (12), L. guyanensis (5), L. braziliensis (3), and Leishmania sp. (01). CONCLUSION: Given the diversity of circulating pathogens, elucidation of the role of the dog in the Leishmania spp. cycle in Amazonian villages is imperative to the surveillance of CL in the region. We present the first report in Brazil, confirmed by sequencing, of canine infection by L. guyanensis, a species highly resistant to treatment in humans, with the drug of first choice (Glucantime®).


Assuntos
Doenças do Cão , Leishmania guyanensis , Leishmaniose , Animais , Brasil/epidemiologia , Cidades , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Leishmania/classificação , Leishmania/genética , Leishmania guyanensis/genética , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Leishmaniose/veterinária
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