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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469376

RESUMO

Abstract Insects' ethology is an important factor when it is desired to carry out pest management. This knowledge makes it possible to manipulate behavioral activities, repel, or attract insects according to needs and interests. The maize weevil Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae), one of the main stored grain pests, has been the target of studies of behavioral changes studies through natural substances due to its resistance to different insecticidal classes. Thus, this study aimed to evaluate the effect of sublethal concentrations of neem extract and copaiba oil on the locomotor behavior of S. zeamais. The behavioral characteristic considered were walking activity, the frequency of contact of insects with the treated grain mass, and the time spent for this behavior. The walking activity of the S. zeamais increased with exposure to Neem extract and Copaiba oil. In general, the Neem extract and Copaiba oil-induced more contact with grain mass than the control, suggesting an attractive effect on the insect, however more significant for the Neem oil. The insect's behavior was altered, presenting a specific path due to Copaiba oil and Neem extract stimuli. These results indicate that Copaiba oil and Neem extract can be a potential alternative for controlling S. zeamais on stored products since changes in this pests' behavior can reduce qualitative and quantitative grain damage. Thus, the development of products based on Copaiba oil and Neem extract may be helpful for storage pest management.


Resumo A etologia dos insetos é um fator importante quando se deseja relizar manejo de pragas. Através deste conhecimento, é possível manipular atividades comportamentais, repelir, ou atrair os insetos de acordo com as necessidades e interesses. O gorgulho do milho Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae), uma das principais pragas de grãos armazenados tem sido alvo de estudos de alterações comportamentais através de substâncias naturais devido à sua resistência a diferentes classes de insecticidas. Assim, este estudo teve como objetivo avaliar o efeito de concentrações subletais de extrato de neem e do óleo de copaíba sobre o comportamento de movimentação de S. zeamais. As características comportamentais consideradas foram: a atividade de caminhamento, a frequência do contato dos insetos com a massa de grãos tratada, e o tempo gasto para realização destes comportamentos. A atividade de caminhamento do S. zeamais aumentou quando os insetos foram expostos ao extrato de Neem e ao óleo de copaíba. Em geral, o extrato de Neem e o óleo de Copaíba induziram mais contato com a massa de grãos do que o controle, sugerindo um efeito atrativo sobre o inseto, contudo este efeito foi mais significativo para o óleo de Neem. O comportamento do inseto foi alterado, apresentando um caminhamento específico devido aos estímulos do óleo de copaíba e do extrato de Neem. Estes resultados indicam que o óleo de copaíba e o extrato de Neem podem ser alternativas potenciais para o controle do S. zeamais em produtos armazenados, uma vez que alterações no comportamento desta praga podem reduzir os danos qualitativos e quantitativos nos grãos. Assim, o desenvolvimento de produtos baseados no óleo de copaíba e no extrato de Neem pode ser útil para o manejo de pragas de armazenamento.

2.
Braz J Biol ; 84: e261972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35792737

RESUMO

At the global level, Sorghum bicolor (L.), is one of the most important crops, which ranks fifth among all cereals. It is cultivated in Africa, Asia, Oceania and the Americas, where it serves as a source of food and feed for humans and animals, respectively. However, production is constrained by several factors including pests and diseases. Among the pests that are known to attack Sorghum, Schizaphis graminum (Rondani), commonly called the green cereal aphid, is the most destructive pest of sorghum. S. graminum damage to sorghum is worsen by water deficit which favors its occurrence. Limited information on the spatial distribution of the pest and its natural enemies impedes the development of ecologically friendly management strategies. Therefore, the objective of this research was to determine the spatiotemporal distribution of S. graminum and its natural enemy Coccinella septempunctata (L.) during the vegetative and reproductive stage of the crop using geostatistical analysis. The spatiotemporal distribution of S. graminum was influenced by Sorghum development stage, surrounding landscape, and presence of its main predator C. septempunctata. Moreover, the abundance of C. septempunctata was influenced by the density of S. graminum. The findings from this study are required for developing sustainable pest management strategies against S. graminum.


Assuntos
Afídeos , Besouros , Sorghum , Animais , Produtos Agrícolas , Grão Comestível
3.
Braz J Biol ; 84: e254628, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35239787

RESUMO

Insects' ethology is an important factor when it is desired to carry out pest management. This knowledge makes it possible to manipulate behavioral activities, repel, or attract insects according to needs and interests. The maize weevil Sitophilus zeamais (Mots., 1855) (Coleoptera: Curculionidae), one of the main stored grain pests, has been the target of studies of behavioral changes studies through natural substances due to its resistance to different insecticidal classes. Thus, this study aimed to evaluate the effect of sublethal concentrations of neem extract and copaiba oil on the locomotor behavior of S. zeamais. The behavioral characteristic considered were walking activity, the frequency of contact of insects with the treated grain mass, and the time spent for this behavior. The walking activity of the S. zeamais increased with exposure to Neem extract and Copaiba oil. In general, the Neem extract and Copaiba oil-induced more contact with grain mass than the control, suggesting an attractive effect on the insect, however more significant for the Neem oil. The insect's behavior was altered, presenting a specific path due to Copaiba oil and Neem extract stimuli. These results indicate that Copaiba oil and Neem extract can be a potential alternative for controlling S. zeamais on stored products since changes in this pests' behavior can reduce qualitative and quantitative grain damage. Thus, the development of products based on Copaiba oil and Neem extract may be helpful for storage pest management.


Assuntos
Controle de Insetos , Inseticidas , Óleos Voláteis , Extratos Vegetais , Gorgulhos , Animais , Controle Comportamental , Inseticidas/farmacologia , Melia/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia
9.
J Hosp Infect ; 113: 145-154, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33852950

RESUMO

BACKGROUND: SARS-CoV-2 predisposes patients to secondary infections; however, a better understanding of the impact of coinfections on the outcome of hospitalized COVID-19 patients is still necessary. AIM: To analyse death risk due to coinfections in COVID-19 patients. METHODS: The odds of death of 212 severely ill COVID-19 patients were evaluated, with detailed focus on the risks for each pathogen, site of infection, comorbidities and length of hospitalization. FINDINGS: The mortality rate was 50.47%. Fungal and/or bacterial isolation occurred in 89 patients, of whom 83.14% died. Coinfected patients stayed hospitalized longer and had an increased odds of dying (odds ratio (OR): 13.45; R2 = 0.31). The risk of death was increased by bacterial (OR: 11.28) and fungal (OR: 5.97) coinfections, with increased levels of creatinine, leucocytes, urea and C-reactive protein. Coinfections increased the risk of death if patients suffered from cardiovascular disease (OR: 11.53), diabetes (OR: 6.00) or obesity (OR: 5.60) in comparison with patients with these comorbidities but without pathogen isolation. The increased risk of death was detected for coagulase-negative Staphylococcus (OR: 25.39), Candida non-albicans (OR: 11.12), S. aureus (OR: 10.72), Acinetobacter spp. (OR: 6.88), Pseudomonas spp. (OR: 4.77), and C. albicans (OR: 3.97). The high-risk sites of infection were blood, tracheal aspirate, and urine. Patients with coinfection undergoing invasive mechanical ventilation were 3.8 times more likely to die than those without positive cultures. CONCLUSION: Severe COVID-19 patients with secondary coinfections required longer hospitalization and had higher risk of death. The early diagnosis of coinfections is essential to identify high-risk patients and to determine the right interventions to reduce mortality.


Assuntos
Infecções Bacterianas/mortalidade , COVID-19/mortalidade , Coinfecção/mortalidade , Micoses/mortalidade , Adulto , Idoso , Infecções Bacterianas/complicações , COVID-19/complicações , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Micoses/complicações , Respiração Artificial
10.
Int Endod J ; 54(8): 1362-1368, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33760261

RESUMO

AIM: To compare microcrack formation in roots of extracted teeth after the shaping of straight and curved root canals with hand, rotary and reciprocating files using micro-computed tomographic (micro-CT) analysis. METHODOLOGY: Thirty straight mandibular incisors and 30 severely curved mesial roots of mandibular molars were randomly divided into 6 experimental groups (n = 10) according to the systems used for the root canal preparation and the root canal curvature: ProTaper Universal for Hand Use (Dentsply Sirona, Ballaigues, Switzerland), HyFlex EDM (Coltene-Whaledent, Altstätten, Switzerland) and Reciproc Blue (VDW, Munich, Germany) files used in mandibular incisors (straight canals) and mesial roots of mandibular molars (curved canals). The roots were imaged with micro-CT scanning at an isotropic resolution of 14 µm before and after root canal preparation, and the cross-sectional images generated were assessed to detect microcracks. RESULTS: All dentinal defects identified after root canal preparation were already present before instrumentation, and no new microcracks were detected. Dentinal microcracks were present in 19% (ProTaper Universal for Hand Use), 11% (Hyflex EDM) and 23% (Reciproc Blue) of the cross-sections when the instrumentation was performed in mandibular incisors. Instrumentation of mandibular molars revealed microcracks in 15% (ProTaper Universal for Hand Use), 16% (Hyflex EDM) and 17% (Reciproc Blue) of the cross-sections. CONCLUSIONS: Preparation of straight and curved root canals with ProTaper Universal for Hand Use, HyFlex EDM and Reciproc Blue systems did not produce microcracks in extracted teeth when evaluated with micro-CT.


Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Estudos Transversais , Cavidade Pulpar/diagnóstico por imagem , Alemanha , Microtomografia por Raio-X
11.
Mater Today Bio ; 8: 100086, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33319188

RESUMO

Nucleic acids are relevant biopolymers in therapy and diagnosis, for which their purity and biological activity are of crucial relevance. However, these features are difficult to achieve by cost-effective methods. Herein, we report the functionalization of a macroporous chromatographic support functionalized with an ionic liquid (IL) with remarkable performance to purify nucleic acids. An initial screening with distinct IL chemical structures supported in silica was carried out, allowing to identify the IL 1-methyl-3-propylimidazolium chloride as the most promising ligand. A chromatographic macroporous matrix able to be used in preparative liquid chromatography was then functionalized and binding/elution studies were performed. The IL 1-methyl-3-propylimidazolium chloride acts as a multimodal ligand with a remarkable dynamic binding capacity. This macroporous support allows the (one-step) purification of nucleic acids, namely small RNAs, ribosomal RNA, and genomic DNA, from a bacterial lysate, and can be regenerated and reused without compromising its separation performance.

12.
Eur Rev Med Pharmacol Sci ; 24(19): 10222-10224, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33090432

RESUMO

OBJECTIVE: The study aimed to review and report the current evidence supporting the use of mouthwashes as a preprocedural protocol on dental offices. MATERIALS AND METHODS: This study is a secondary one that performed a comprehensive literature search of scientific studies published up to 10th August 2020 in PubMed, Scopus, Web of Science, and Scientific Electronic Library Online (Scielo) databases. The electronic search strategy was performed using free text and DeCS/MeSH terms. RESULTS: Only five studies were included in this work, despite 140 studies that were identified with the research strategy. In vivo studies were carried out in two works, in vitro studies were described in two papers, and a in silico approach was used in one work. No cetylpyridinium chloride studies were identified, while chlorhexidine and povidone studies were more studied. CONCLUSIONS: There is reduced evidence about how preprocedural mouthwashes decrease SARS-CoV-2 salivary load.


Assuntos
COVID-19/prevenção & controle , Assistência Odontológica/métodos , Antissépticos Bucais/farmacologia , Antissépticos Bucais/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , Humanos , Carga Viral/efeitos dos fármacos
13.
Int J Biol Macromol ; 134: 722-729, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31078596

RESUMO

Alginates are fairly abundant in nature and possess many interesting properties, including their biocompatibility and ability to absorb large amounts of water. Hence, increasing interest in their derivatization has been observed and the determination of the number of newly introduced functionalities has become a key issue. For this purpose, literature generally reports on conventional 1H-NMR spectra, typically recorded at elevated temperatures and/or after hydrolysis of the alginate to circumvent line broadening effects resulting from the high viscosity. The present work reports on the modification of alginate with methacrylate functionalities and determination of the resulting degree of substitution (DS), i.e. the number of introduced methacrylate moieties relative to the initial amount of hydroxyl groups along the alginate backbone, via NMR spectroscopy. Freeze-drying and low power water presaturation were applied to improve the quality of the 1H NMR spectra. Nevertheless, it remains a qualitative method, to be used only for mutual comparisons of samples. A new and accurate method for DS determination of methacrylated alginates, based on 13C-NMR spectroscopy, is proposed. Quantitative 13C-NMR spectra were recorded with reduced measuring times by addition of a paramagnetic relaxation agent. The proposed method will also be applicable for other water-soluble functionalized alginates and polysaccharides in general.


Assuntos
Alginatos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Compostos de Vinila/química , Água/química , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Solubilidade , Compostos de Vinila/síntese química
14.
Carbohydr Polym ; 189: 1-9, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29580385

RESUMO

The current paper focuses on the functionalization of κ-carrageenan and gelatin as extracellular matrix polysaccharide and protein mimic respectively to produce hydrogel films for adipose tissue engineering. More specifically, κ-carrageenan as well as gelatin have been functionalized with methacrylate and methacrylamide moieties respectively to enable subsequent UV-induced crosslinking in the presence of a photo-initiator. The gel fraction, the mass swelling ratio and the mechanical properties of both the one-component hydrogels and the protein/polysaccharide blends have been evaluated. The mechanical and swelling properties of the blends could be tuned by varying the hydrogel composition as well as the crosslinking method applied. The in vitro biocompatibility assays indicated a significantly higher cell viability of adipose tissue-derived mesenchymal stem cells seeded onto the blends as compared to the one-component hydrogels. The results show that the blends of gelatin and κ-carrageenan clearly outperform the one-component hydrogels in terms of adipose tissue engineering potential.


Assuntos
Carragenina/química , Gelatina/química , Engenharia Tecidual/métodos , Tecido Adiposo/citologia , Carragenina/farmacologia , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Matriz Extracelular/química , Gelatina/farmacologia , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos
15.
Neotrop Entomol ; 47(2): 318-325, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28822099

RESUMO

Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the major pests of solanaceous plants in South America. It is considered a great threat by the European and Mediterranean Plant Protection Organization due to the serious economic damage that it causes on tomato farms; therefore, controlling this pest is a challenging task in South America. Controlling N. elegantalis at the egg stage is the best way to prevent it from damaging crops; however, thorough studies about the effectiveness of chemicals on the different life stages of this insect pest are lacking. In this study, the effects of different chemical classes were evaluated on N. elegantalis adults, female oviposition behavior, larvae, eggs, and embryonic development. None of the tested insecticides demonstrated toxicity to the adults; however, the results showed that cartap hydrochloride affects oviposition behavior. Moreover, methomyl and cartap hydrochloride exhibited high toxicity against the eggs and larvae, with higher than 80% of mortality. These insecticides interrupted larval hatching and caused alterations in the chorion layer. Flubendiamide and deltamethrin demonstrated toxicity on N. elegantalis larvae; however, lufenuron, indoxacarb, methoxyfenozide, and chlorantraniliprole demonstrated low toxicity on both eggs and larvae, with lower than 70% of mortality. Fruit treated with cartap hydrochloride had a deterrent effect. The ovicidal activity revealed by methomyl and cartap hydrochloride might provide new approaches regarding insecticide effects on eggs. Methomyl, cartap hydrochloride, flubendiamide, and deltamethrin demonstrated toxicity on larvae. The evaluation of the chorion of the eggshell in this study has clarified the toxic effect of methomyl and cartap hydrochloride on eggs.


Assuntos
Inseticidas , Lepidópteros , Animais , Benzamidas , Feminino , Hidrazinas , Controle de Insetos , Hormônios Juvenis , Larva , Metomil , Nitrilas , Oviposição , Óvulo , Oxazinas , Piretrinas , Solanum , Sulfonas , Tiocarbamatos , ortoaminobenzoatos
16.
Toxicon ; 137: 150-157, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28688807

RESUMO

This study compares the role of hepatic cytosolic glutathione transferases (cGST) isoforms of three different bivalve species to a Microcystis aeruginosa extract and purified MC-LR exposure (both at 150 µg MC-LR L-1) for 24 h. Characterization and alterations of the cytosolic GST activities in Mytilus galloprovincialis, Ruditapes philippinarum and Corbicula fluminea were measured using four class-specific substrates and changes in individual GST isoforms expression were achieved by a subsequent two-dimensional electrophoresis analysis. Evaluation of cGST activity basal levels using the four class-specific substrates denoted quantitative differences between the three bivalves. Purified MC-LR did not induce any significant response from bivalves. On the other hand, cell extracts caused significant alterations according to bivalves and substrates. Among the three bivalves, only R. philippinarum showed a significant induction of cGST activity using generic 1-chloro-2,4-dinitrobenzene (CDNB) substrate. However, no significant alterations were detected in these clams by cell extracts using the other specific substrates. In contrast, C. fluminea revealed significant induction of cGST activity when using 3,4-dichloronitrobenzene (DCNB) and ethacrynic acid (EA). In M. galloprovincialis, cell extracts promoted a significant decrease of cGST activity when using EA substrate. Altered protein expression was quantitatively detected upon exposure to cell extracts for one spot in R. philippinarum and another for C. fluminea, both upregulated (2.0 and 8.5-fold, respectively) and identified as a sigma1-class GST in the case of the first. The results showed that the three bivalves presented specific adaptive biotransformation responses to MCs and other cyanobacteria compounds supported by the modulation of distinct cGST classes.


Assuntos
Toxinas Bacterianas/toxicidade , Bivalves/efeitos dos fármacos , Glutationa Transferase/antagonistas & inibidores , Fígado/enzimologia , Microcistinas/toxicidade , Animais , Biotransformação , Bivalves/enzimologia , Isoenzimas/antagonistas & inibidores , Toxinas Marinhas , Microcystis , Proteômica , Extratos de Tecidos/toxicidade
17.
Chem Commun (Camb) ; 53(51): 6899-6902, 2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28607961

RESUMO

The association of kinetic studies, DFT calculations and 1H-7Li NMR analyses allowed the control of the cyclo-ATRP of PEG9DMA and the production of polymethacrylate pseudo crown-ethers of various molar masses. Their potential to act as a solid-state polymer electrolyte in Li-ion batteries has been highlighted and may come from the supramolecular organization of the cyclo-PEG forming a Li+ diffusion channel.

18.
Org Biomol Chem ; 13(36): 9398-404, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26246017

RESUMO

The Glaser-Hay diyne coupling proved to be an efficient cyclisation approach towards diyne containing peptidic macrocycles. A variety of tetrapeptide-based macrocyclic 1,3-diynes were obtained from O-propargylated serine or tyrosine residues using Cu(OAc)2·H2O and NiCl2 under an O2-atmosphere. The effect of the linear 1,3-diyne on peptide conformations was studied by NMR and compared with a macrocycle bearing a saturated linker.


Assuntos
Di-Inos/química , Compostos Macrocíclicos/síntese química , Peptídeos/síntese química , Ciclização , Compostos Macrocíclicos/química , Conformação Molecular , Oxirredução , Peptídeos/química
19.
Arch Toxicol ; 89(11): 1993-2005, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25209565

RESUMO

A direct, fast and sensitive LC-MS/MS method was developed to measure biomarkers for mycotoxin exposure in human urine. In total, 32 biomarkers were quantitatively or semi-quantitatively measured in 32 urine samples of Belgian volunteers using two injections. All urine samples contained deoxynivalenol-15-glucuronide, the major detoxification metabolite of deoxynivalenol, in the ng/mL range. Also deoxynivalenol-3-glucuronide and de-epoxy-deoxynivalenol-glucuronide were present in, respectively, 90 and 25% of the samples, while deoxynivalenol was detected in 60% of the samples, in lower concentrations. Deoxynivalenol glucuronides were the major biomarkers for deoxynivalenol exposure. Ochratoxin A was detected in 70% of the samples in pg/mL. Citrinin and/or dihydrocitrinone were detected in 90% of the samples, also in concentrations of pg/mL. The presence of ochratoxin A and citrinin was confirmed by a second method using sample cleanup by immunoaffinity columns, followed by LC-MS/MS. Our data show that humans are much more exposed to citrinin than realized before and suggest further work on citrinin exposure in relation with ochratoxin A exposure, as both mycotoxins are nephrotoxic.


Assuntos
Cromatografia Líquida/métodos , Micotoxinas/urina , Espectrometria de Massas em Tandem/métodos , Tricotecenos/urina , Adulto , Bélgica , Biomarcadores/urina , Citrinina/análogos & derivados , Citrinina/urina , Feminino , Glucuronídeos/urina , Humanos , Masculino , Ocratoxinas/urina
20.
Rev. argent. transfus ; 39(1/2): 31-42, 2013. tab, graf
Artigo em Espanhol | LILACS | ID: lil-724699

RESUMO

La transfusión de productos sanguíneos tiene como objetivo restaurar o mantener la capacidad de transportar oxígeno, y la homeostasis del volumen sanguíneo. En los últimos años se han introducido mejoras en las indicaciones de los productos sanguíneos ya que se ha demostrado que su uso supone un riesgo para el paciente y también es costoso para el sistema de salud. Hay grupos que están trabajando con la práctica de la "cirugía sin sangre". El propósito principal de realizar intervenciones utilizando poca sangre ("cirugía sin sangre") está enfocada en minimizar las pérdidas y reducir o eliminar la exposición a los componentes sanguíneos alogeneicos. Los riesgos asociados con las transfusiones de sangre han sido bien documentados, y el objetivo de los centros de "cirugía sin sangre" es evitar complicaciones y el uso innecesario de las transfusiones. Hay una estrategia universal de uso conservador de la sangre que es aplicable a todos los pacientes y poblaciones. Factores tales como las condiciones preexistentes van a cambiar el enfoque en casos específicos. Un protocolo de cirugía exitosa con poca pérdida de sangre requiere trabajo en equipo y la cooperación entre el banco de sangre, hematólogos, cirujanos y anestesiólogos, para asegurar que se cumplan los objetivos de minimizar la pérdida de sangre y evitar las transfusiones, sin poner en riesgo la vida y el bienestar del paciente.


Assuntos
Humanos , Procedimentos Cirúrgicos Operatórios/métodos , Transfusão de Sangue , Transfusão de Componentes Sanguíneos , Consumo de Oxigênio , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Homeostase , Perda Sanguínea Cirúrgica/prevenção & controle , Volume Sanguíneo
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