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1.
Front Microbiol ; 15: 1320168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832116

RESUMO

Fresh produce can be contaminated by enteric pathogens throughout crop production, including through contact with contaminated agricultural water. The most common outbreaks and recalls in fresh produce are due to contamination by Salmonella enterica and Shiga toxin-producing E. coli (STEC). Thus, the objectives of this study were to investigate the prevalence of markers for STEC (wzy, hly, fliC, eaeA, rfbE, stx-I, stx-II) and Salmonella (invA) in surface water sources (n = 8) from produce farms in Southwest Georgia and to determine correlations among the prevalence of virulence markers for STEC, water nutrient profile, and environmental factors. Water samples (500 mL) from eight irrigation ponds were collected from February to December 2021 (n = 88). Polymerase chain reaction (PCR) was used to screen for Salmonella and STEC genes, and Salmonella samples were confirmed by culture-based methods. Positive samples for Salmonella were further serotyped. Particularly, Salmonella was detected in 6/88 (6.81%) water samples from all ponds, and the following 4 serotypes were detected: Saintpaul 3/6 (50%), Montevideo 1/6 (16.66%), Mississippi 1/6 (16.66%), and Bareilly 1/6 (16.66%). Salmonella isolates were only found in the summer months (May-Aug.). The most prevalent STEC genes were hly 77/88 (87.50%) and stx-I 75/88 (85.22%), followed by fliC 54/88 (61.63%), stx-II 41/88 (46.59%), rfbE 31/88 (35.22%), and eaeA 28/88 (31.81%). The wzy gene was not detected in any of the samples. Based on a logistic regression analysis, the odds of codetection for STEC virulence markers (stx-I, stx-II, and eaeA) were negatively correlated with calcium and relative humidity (p < 0.05). A conditional forest analysis was performed to assess predictive performance (AUC = 0.921), and the top predictors included humidity, nitrate, calcium, and solar radiation. Overall, information from this research adds to a growing body of knowledge regarding the risk that surface water sources pose to produce grown in subtropical environmental conditions and emphasizes the importance of understanding the use of abiotic factors as a holistic approach to understanding the microbial quality of water.

2.
Anal Biochem ; 689: 115503, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38453049

RESUMO

Terpenes play a vital role in plant defense; tomato plants produce a diverse range of terpenes within specialized glandular trichomes, influencing interactions with herbivores, predators, and pollinators. This study employed two distinct methods, namely leaf dip and maceration, to extract trichomes from tomato leaves. Terpene quantification was carried out using Gas Chromatography-Mass Spectrometry (GC-MS). The leaf dip method proved effective in selectively targeting trichome content, revealing unique extraction patterns compared to maceration. The GC-MS method demonstrated high linearity, accuracy, sensitivity, and low limits of detection and quantification. Application of the method to different tomato species (Solanum pennellii, Solanum pimpinellifolium, Solanum galapagense, Solanum habrochaites, and Solanum lycopersicum) identified significant variation in terpene content among these species, highlighting the potential of specific accessions for breeding programs. Notably, the terpene α-zingiberene, known for its repellency against whiteflies, was found in high quantities (211.90-9155.13 µg g-1) in Solanum habrochaites accession PI209978. These findings provide valuable insights into terpenoid diversity for plant defense mechanisms, guiding future research on developing pest-resistant tomato cultivars. Additionally, the study underscores the broader applications of terpenes in agriculture.


Assuntos
Solanum lycopersicum , Solanum , Terpenos/análise , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais
3.
Adv Ther ; 41(4): 1606-1620, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38407790

RESUMO

INTRODUCTION: This literature review and exploratory network meta-analysis (NMA) aimed to compare the clinical effectiveness and tolerability of selective internal radiation therapy (SIRT) using yttrium-90 (Y-90) resin microspheres, regorafenib (REG), trifluridine-tipiracil (TFD/TPI), and best supportive care (BSC) in adult patients with chemotherapy-refractory or chemotherapy-intolerant metastatic colorectal cancer (mCRC). METHODS: In light of recently published data, the literature was searched to complement and update a review published in 2018. Studies up to December 2022 comparing two or more of the treatments and reporting overall survival (OS), progression-free survival (PFS), or incidence of adverse events (AE) were included. The NMA compared hazard ratios (HRs) for OS and PFS using Markov chain Monte Carlo techniques. RESULTS: Fifteen studies were included, with eight studies added (none addressing SIRT). All active treatments improved OS in relation to BSC. SIRT had the longest OS among all treatments, although without statistically significant differences (HR [95% credible interval] for SIRT, 0.48 [0.27, 0.87]; TFD/TPI, 0.62 [0.46, 0.83]; REG, 0.78 [0.57, 1.05]) in a fixed effects model. Information regarding SIRT was insufficient for PFS analysis, and TFD/TPI was the best intervention (HR 2.26 [1.6, 3.18]). One SIRT study reported radioembolization-induced liver disease in > 10% of the sample; this was symptomatically managed. Non-haematological AEs (hand-foot skin reaction, fatigue, diarrhoea, hypertension, rash or desquamation) were more common with REG, while haematological events (neutropoenia, leukopenia, and anaemia) were more common with TFD/TPI. CONCLUSION: Current evidence supports SIRT treatment in patients with chemotherapy-refractory or chemotherapy-intolerant mCRC compared to newer oral agents, with comparable OS and low incidence of AEs.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Compostos de Fenilureia , Piridinas , Adulto , Humanos , Radioisótopos de Ítrio/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/radioterapia , Metanálise em Rede , Microesferas , Neoplasias do Colo/tratamento farmacológico , Pirrolidinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
4.
Sci Total Environ ; 902: 165620, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37543326

RESUMO

Coastal eutrophication and urban flooding are increasingly important components of global change. Although increased seawater renewal by barrier openings and channelizing are common mitigation measures in coastal lagoons worldwide, their effects on these ecosystems are not fully understood. Here, we evaluated the relationships between human interventions in the watershed, artificial connections to the sea, and the sediment burial rates in an urban coastal lagoon (Maricá lagoon, Southeastern Brazil). Sediment accretion along with nutrient and carbon burial rates were determined in two sediment cores representing the past ∼120 years (210Pb dating) and associated with anthropogenic changes as indicated by historical records and geoinformation analyses. Lagoon infilling and eutrophication, expressed by the average sediment accretion, TP, TN, and OC burial rates, respectively, increased ∼9-18, 13-15, 11-14 and 11-12-fold from the earliest (<1950) to the most recent (2000-2017) period. These multi-proxy records confirm mechanistic links between deforestation, urbanization, and untreated sewage discharges. In addition, our findings reveal artificial connections to the sea may contribute to lagoonal eutrophication and infilling, particularly when not integrated with sewage treatment and forest conservation or reforestation in the watershed. Therefore, increased seawater renewal by physical interventions commonly considered as mitigation measures may in contrast cause severe degradation in coastal lagoons, causing harmful consequences that should be not neglected when implementing management practices.

5.
Arch Oral Biol ; 151: 105715, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37146389

RESUMO

OBJECTIVES: To evaluate the prevalence and morphological characteristics of DI using CBCT. METHODS: A literature search was performed in PubMed, Embase, Scopus, and Web of Science. Inclusion criteria were randomized clinical trials, cross-sectional studies, and prospective and retrospective cohort studies evaluating the morphological characteristics of DI in anterior teeth using CBCT. Three reviewer authors independently screened the studies, applied the eligibility criteria, assessed the risk of bias, and extracted until September (2022). The risk of bias was evaluated using the Joanna Briggs Institute criteria. Meta-analyses of proportions were used for estimate the prevalence DI according to factors at participant and tooth levels. RESULTS: Six studies were included in the meta-analysis. Among 7373 individuals, a prevalence of 7.45 % of DI was observed (n = 258; τ2 = 0.0096; CI of 4.51-11.3; p < 0.05), with no significant influence of sex. Regarding laterality, unilateral DI showed higher mean prevalence (4.30 %; CI of 2.03-7.33). Among the 382 anterior teeth with DI (0.72 %), the most affected tooth was the upper lateral incisor (5.12 %; n = 329; CI of 2.35-8.86; p < 0.001), type I was the most prevalent (0.59 %; CI of 0.24-1.08) and the presence of open apex and periradicular pathology ranged from 4.3 % to 22.72 % and 3.5-77.92 %, respectively. CONCLUSIONS: The prevalence of individuals with dens invaginatus was 7.45 %, the most affect tooth was the upper lateral incisor with a prevalence of 5.12 % unilaterally and type I was the most prevalent morphology.


Assuntos
Dens in Dente , Tratamento do Canal Radicular , Humanos , Dens in Dente/diagnóstico por imagem , Dens in Dente/epidemiologia , Estudos Retrospectivos , Estudos Transversais , Prevalência , Estudos Prospectivos , Tomografia Computadorizada de Feixe Cônico
6.
Sci Rep ; 13(1): 5958, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37045866

RESUMO

Dengue viruses (DENVs) are mosquito-borne flaviviruses causing millions of human infections each year and pose a challenge for public health systems worldwide. Aedes aegypti is the principal vector species transmitting DENVs to humans. Controlling Ae. aegypti is difficult due to the abundance of breeding sites and increasing insecticide resistance in the vector populations. Developing new vector control strategies is critical for decreasing the disease burden. One potential approach is genetically replacing Ae. aegypti populations with vector populations highly resistant to DENV transmission. Here, we focus on an alternative strategy for generating dengue 2 virus (DENV-2) resistance in genetically-modified Ae. aegypti in which the mosquitoes express an inactive form of Michelob_x (Mx), an antagonist of the Inhibitor of Apoptosis (IAP), to induce apoptosis in those cells in which actively replicating DENV-2 is present. The inactive form of Mx was flanked by the RRRRSAG cleavage motif, which was recognized by the NS2B/NS3 protease of the infecting DENV-2 thereby releasing and activating Mx which then induced apoptosis. Our transgenic strain exhibited a significantly higher mortality rate than the non-transgenic control when infected with DENV-2. We also transfected a DNA construct containing inactive Mx fused to eGFP into C6/36 mosquito cells and indirectly observed Mx activation on days 3 and 6 post-DENV-2 infections. There were clear signs that the viral NS2B/NS3 protease cleaved the transgene, thereby releasing Mx protein into the cytoplasm, as was confirmed by the detection of eGFP expression in infected cells. The present study represents proof of the concept that virus infection can be used to induce apoptosis in infected mosquito cells.


Assuntos
Aedes , Vírus da Dengue , Dengue , Animais , Humanos , Vírus da Dengue/genética , Morte Celular , Transgenes , Peptídeo Hidrolases/genética
7.
Trop Anim Health Prod ; 55(3): 142, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016138

RESUMO

Rumen-protected fat (RPF) was produced in the 1st experimental stage through melt-emulsification technique using buriti oil (BO) as core, at concentrations of 10% (BO10), 20% (BO20), and 30% (BO30) (w/w), and carnauba wax (CW) as encapsulant material. After obtention and characterization, protected fat microspheres were tested in a 2nd experimental stage on the sheep' diet using six castrated 2-year-old male Santa Ines with initial weight 48.9 ± 5.23 kg, fistulated in rumen and distributed in a double Latin square design with 3 treatments × 3 periods, to evaluate rumen pH, temperature, protozoal count, and blood parameters. There was no difference (P > 0.05) among RPF microspheres for microencapsulation yield. However, microencapsulation efficiency increased (P < 0.05) with BO addition ranging from 36 to 61.3% for BO10 and BO30, respectively. The inclusion of BO10 in the sheep's diet did not affect the ruminal dry matter degradability (DMD) of BO over time (P > 0.05); however, BO20 and BO30 had higher (P < 0.05) DMD values than BO10. No significant differences were observed among RPF for rumen pH and temperature (P > 0.05). There was an increase (P < 0.05) in the protozoal population in the rumen environment due to the microencapsulated BO30 inclusion. There was also increase (P < 0.05) in serum albumin, cholesterol, aspartate aminotransferase (ALT), and gamma-glutamyltransferase (GGT), and a reduction (P < 0.05) in serum triglycerides of the sheep when RPF microspheres increased in the diet. Melt-emulsification proved to be a good technique for microencapsulation of buriti oil into the carnauba wax matrix. RPF from buriti oil protected into carnauba wax is recommended for sheep diet because it increases energy density, without adverse effects on the protozoal populations and blood serum metabolites from the bypass effect in the rumen.


Assuntos
Dieta , Rúmen , Animais , Masculino , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Digestão , Fermentação , Rúmen/metabolismo , Ovinos
8.
Food Chem ; 407: 135101, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481474

RESUMO

Growers commonly wash fresh produce with chemical sanitizers during postharvest handling. However, these sanitizers can be harsh to washing systems and pose a health risk to workers. Essential oils (EOs) can be used as alternatives to chemical sanitizers in produce washing. Previous studies reveal that the EOs from thyme, oregano, cinnamon, and clove are the main EOs evaluated in the studies as potential sanitizers for the washing of produce. The use of EOs and surfactants, such as tween80 and cetylpyridinium chloride, might be used to improve the antimicrobial activity of emulsions. However, studies are still required to evaluate the potential effect of different chemical components of EOs and preparations. Also, it is recommended that researchers focus on overcoming obstacles regarding EOs application in washing systems, including the high levels of EO required to reduce bacterial growth, undesired organoleptic impact on produce, and the poor solubility of EOs in aqueous solution.


Assuntos
Óleos Voláteis , Humanos , Óleos Voláteis/farmacologia , Tensoativos , Testes de Sensibilidade Microbiana
9.
Anal Biochem ; 655: 114851, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35977597

RESUMO

L: operculata is a plant commonly found in the North and Northeast of Brazil. Although the regional population knows its medicinal potential, there are few scientific studies about its antimicrobial potential. Thus, this study aimed to characterize the proteins from L. operculata seeds extracted using different solutions and evaluate their antimicrobial potentials. The protein extracts obtained with NaCl and sodium acetate buffer presented the best inhibitory activities against Candida albicans and C. krusei. The study of the mechanism of action revealed proteins from L. operculata seeds induced pore formation on the membrane and ROS overaccumulation. Scanning Electron Microscopy images also showed severe morphological changes in Candida albicans and C. krusei. Proteins from L.operculata seeds did not show antibacterial activity. The enzymatic assays revealed the presence of proteolytic enzymes, serine and cysteine protease inhibitors, and chitinases in both protein extracts. Proteomic analysis by LC-ESI-MS/MS identified 57 proteins related to many biological processes, such as defense to (a)biotic stress, energetic metabolism, protein folding, and nucleotide metabolism. In conclusion, the L. operculata seed proteins have biotechnological potential against the human pathogenic yeasts Candida albicans and C. krusei.


Assuntos
Candida albicans , Luffa , Antibacterianos , Humanos , Testes de Sensibilidade Microbiana , Proteômica , Sementes , Espectrometria de Massas em Tandem
10.
Dent Mater ; 38(5): 789-796, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35450703

RESUMO

OBJECTIVES: This study aimed to evaluate the water content and uptake of CAD/CAM chairside composites over 60 days using coulometric Karl Fischer (KF) titration. METHODS: Rectangular plates (10 ×10×1 mm3 of thickness) were cut from the blocks of composites Cerasmart 270 (CS), Katana Avencia (KA), Grandio Blocs (GB), and Lava Ultimate (LU). Specimens were stored in distilled water for up to 60 days at 37 °C, and non-stored specimens were used as a control (n = 5). Specimens were isothermally heated at 200 °C, and the water content was evaporated and transferred to the titration cell throughout a nitrogen gas flow. The KF coulometer determined the percentage of water in each specimen. Data were analyzed by 2-way ANOVA and Tukey`s test (α = 0.05). RESULTS: The water content of non-stored specimens ranged from 0.29 to 1.66 wt% (6.9-32.9 µg/mm3) for GB and LU, respectively. The water content increased underwater storage (0.82-2.96 wt% after 60 days). The extend of water sorption (11.9-26.1 µg/mm3) among the materials was directly related to their base water content. No additional water content increase was observed after 7 (LU and KA) or 21 (GB and CS) days. Measuring the water content in wt% or µg/mm3 affected the ranking of materials when KA and CS were analyzed. SIGNIFICANCE: Composites with higher base water content also presented higher water sorption. KF titrationshowed to be a reliable method to measure the water sorption of composites, including their base water content.


Assuntos
Cerâmica , Água , Resinas Compostas , Desenho Assistido por Computador , Teste de Materiais , Propriedades de Superfície
11.
Pharmaceutics ; 13(6)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073997

RESUMO

Onychomycosis induced by Candida spp. has several limitations regarding its treatment. Nail lacquers display the potential to overcome these drawbacks by providing therapeutic compliance and increasing local drug bioavailability. Thus, this work aimed to produce a nail lacquer loaded with Amphotericin B (AmB) and evaluate its performance. The AmB-loaded nail lacquer was produced and preliminarily characterized. An AmB quantification method was developed. Stability, drug release, permeability and anti-Candida activity assays were conducted. The analytical method validation met the acceptance criteria. The drug loading efficiency was 100% (0.02 mg/g of total product), whereas the AmB stability was limited to ≅7 days (≅90% remaining). The nail lacquer displayed a drying time of 187 s, non-volatile content of around 20%w/w, water-resistance of approximately 2%w/w of weight loss and satisfactory in vitro adhesion. Moreover, the in vitro antifungal activity against different Candida spp. strains was confirmed. The AmB release and the ex vivo permeability studies revealed that AmB leaves the lacquer and permeates the nail matrix in 47.76 ± 0.07% over 24 h. In conclusion, AmB-loaded nail lacquer shows itself as a promising extemporaneous dosage form with remarkable anti-Candida activity related to onychomycosis.

12.
iScience ; 24(4): 102352, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33870142

RESUMO

Calonectria hemileiae, a fungus associated with pustules of the coffee leaf rust (CLR, Hemileia vastatrix) in Brazil, was tested in vitro and in planta to assess its biocontrol potential. The fungus inhibited the germination of rust spores by over 80%. CLR severity was reduced by 93% when Calonectria was applied to coffee leaf discs inoculated with H. vastatrix, whilst a reduction of 70-90% was obtained for in planta experiments. Mycoparasitism was demonstrated through the fulfillment of Koch's postulates. Elucidation of the biochemical interaction between Calonectria and Hemileia on coffee plants indicated that the mycoparasite was able to increase plant resistance to rust infection. Coffee plants sprayed with Calonectria alone showed greater levels of chitinase, ß-1,3-glucanase, ascorbate peroxidase and peroxidase. Although effective in controlling the rust, fungicide applications damaged coffee photosynthesis, whereas no harm was caused by Calonectria. We conclude that C. hemileiae shows promise as a biocontrol agent of CLR.

13.
Bioorg Med Chem ; 30: 115924, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333448

RESUMO

Histamine acts through four different receptors (H1R-H4R), the H3R and H4R being the most explored in the last years as drug targets. The H3R is a potential target to treat narcolepsy, Parkinson's disease, epilepsy, schizophrenia and several other CNS-related conditions, while H4R blockade leads to anti-inflammatory and immunomodulatory effects. Our group has been exploring the dihydrobenzofuranyl-piperazines (LINS01 series) as human H3R/H4R ligands as potential drug candidates. In the present study, a set of 12 compounds were synthesized from adequate (dihydro)benzofuran synthons through simple reactions with corresponding piperazines, giving moderate to high yields. Four compounds (1b, 1f, 1g and 1h) showed high hH3R affinity (pKi > 7), compound 1h being the most potent (pKi 8.4), and compound 1f showed the best efficiency (pKi 8.2, LE 0.53, LLE 5.85). BRET-based assays monitoring Gαi activity indicated that the compounds are potent antagonists. Only one compound (2c, pKi 7.1) presented high affinity for hH4R. In contrast to what was observed for hH3R, it showed partial agonist activity. Docking experiments indicated that bulky substituents occupy a hydrophobic pocket in hH3R, while the N-allyl group forms favorable interactions with hydrophobic residues in the TM2, 3 and 7, increasing the selectivity towards hH3R. Additionally, the importance of the indole NH in the interaction with Glu5.46 from hH4R was confirmed by the modeling results, explaining the affinity and agonistic activity of compound 2c. The data reported in this work represent important findings for the rational design of future compounds for hH3R and hH4R.


Assuntos
Antagonistas dos Receptores Histamínicos/farmacologia , Piperazinas/farmacologia , Receptores Histamínicos H3/metabolismo , Receptores Histamínicos H4/antagonistas & inibidores , Relação Dose-Resposta a Droga , Antagonistas dos Receptores Histamínicos/síntese química , Antagonistas dos Receptores Histamínicos/química , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Receptores Histamínicos H4/metabolismo , Relação Estrutura-Atividade
14.
Neotrop. ichthyol ; 19(1): e200136, 2021. tab, graf
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1287439

RESUMO

Pygocentrus nattereri is a carnivorous fish widely distributed in the Brazilian wetland and occupies different river strata. Based on the sexual maturity, the standard length (SL) has been used to categorize age and physiological attributes. However, hematological parameters and their relationship with age and growth features are unknow. Here, the aim was to evaluate the hematological profile and leukocyte data of juvenile and adult specimens, associating it with SL. Specimens of both sexes were weighted, and SL were measured for classify as juveniles (SL ≤16.0 cm) and adults (SL ≥16.1 cm). Blood was collected to perform the hemogram, for leukocyte quantification and ultrastructural descriptions. In general, hemogram values and leukocyte, lymphocyte, and monocyte counts were high in juveniles. Hemogram variables were negatively correlated with SL. Thrombocyte and neutrophil counts were higher in adults than in juveniles. SL was correlated with leukogram variables. Ultrastructural analysis showed that granular leukocyte count in P. nattereri was similar another fishes. PAS-positive granular leukocytes are slightly smaller than neutrophils and are characterized by dense elongated and semi-lunar shapes in the cytoplasm. Our results suggest that age-based SL may be useful for the analysis of the relationship between P. nattereri health status and wetland aquatic environments.(AU)


Pygocentrus nattereri é um peixe carnívoro amplamente distribuído no pantanal brasileiro e ocupa diferentes estratos de rios. Com base na maturidade sexual, o comprimento padrão (CP) tem sido usado para categorizar a idade e os atributos fisiológicos. No entanto, os parâmetros hematológicos e sua relação com a idade e características de crescimento são desconhecidos. O objetivo foi avaliar o perfil hematológico e leucocitário de espécimes juvenis e adultos, associando-o ao CP. Espécimes de ambos os sexos foram pesados e os CPs foram medidos para classificação em juvenis (CP ≤16,0 cm) e adultos (CP ≥16,1 cm). Foi coletado sangue para realização do hemograma, perfil e morfologia dos leucócitos. Em geral, os valores do hemograma e as contagens de leucócitos, linfócitos e monócitos foram maiores nos jovens. A contagem de trombócitos e neutrófilos foi maior em adultos do que em jovens. A análise ultraestrutural mostrou que a contagem de leucócitos granulares em P. nattereri foi semelhante a outros peixes. Os leucócitos granulares PAS-positivos são menores do que os neutrófilos, sendo caracterizados por formas alongadas e semilunares densas no citoplasma. Nossos resultados sugerem que CP é útil para a análise da relação entre o estado de saúde de P. nattereri em ambientes aquáticos alagados.(AU)


Assuntos
Animais , Plaquetas , Caraciformes/sangue , Peixes , Contagem de Leucócitos , Hematologia
15.
Dent Mater ; 36(10): e293-e301, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32636077

RESUMO

OBJECTIVE: This study evaluated the properties of experimental dual-cured cements containing thiourethane (TU) and low concentrations of p-Tolyldiethanolamnie (DHEPT) and benzoyl peroxide (BPO) as chemical initiators. METHODS: BisGMA/TEGDMA-based dual-cured cement was formulated with 1.0 wt% DHEPT and 0.75 wt% BPO as initiators and used as control. The concentration of BPO was adjusted to 0.1 wt% in catalyst paste of experimental cements, and two base pastes containing TU and 0.5 wt% or 0.25 wt% of DHEPT were formulated. The rheological behavior and kinetics of polymerization of cements were assessed in the absence of light activation. The kinetics of polymerization was also evaluated for cements light-activated immediately or 5 min after the start of mixing. Polymerization stress, flexural strength and elastic modulus (n = 5) were also evaluated under these conditions. RESULTS: Cements with TU presented lower viscosity than the control, improved working time (0.25% DHEPT > 0.5% DHEPT) and higher conversion in the absence of light-activation. Delaying the light-activation reduced the maximum rate of polymerization (Rpmax) but did not affect the conversion or stress. The addition of TU increased the Rpmax and conversion, and reduced the stress when compared to the control, without affecting the flexural strength. Except for the control with delayed light-activation (highest values), the other experimental conditions yielded similar modulus. SIGNIFICANCE: Adding TU and using a low concentration of DHEPT/BPO resulted in dual-cured cements with longer working time, reduced polymerization stress and increased conversion even in the absence of light, with no significant effect on the mechanical properties.


Assuntos
Cimentos de Resina , Bis-Fenol A-Glicidil Metacrilato , Teste de Materiais , Polimerização , Estresse Mecânico , Tempo
16.
Front Pharmacol ; 11: 600132, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424609

RESUMO

The AT1 receptor (AT1R) has a major role in the Renin-Angiotensin System, being involved in several physiological events including blood pressure control and electrolyte balance. The AT1R is a member of the G protein coupled receptors (GPCR) family, classically known to couple Gαq and engage ß-arrestin recruitment. Both G protein and arrestin signaling pathways are involved in modulation of different downstream kinases. A previous study reported that mutations in the AT1R (A244S and I103T-A244S) were positively correlated with higher risk of atrial fibrillation in men. Based on that report, we aimed to investigate if these mutations, including I103T only, could affect AT1R signal transduction profile, and consequently, implicate in atrial fibrillation outcome. To address that, we engineered an AT1R carrying the above-mentioned mutations, and functionally evaluated different signaling pathways. Phosphokinase profiler array to assess the mutations downstream effects on kinases and kinase substrates phosphorylation levels was used. Our results show that the I103T-A244S mutant receptor presents decreased ß-arrestin 2 recruitment, which could lead to a harmful condition of sustained Gαq signaling. Moreover, the phosphokinase profiler array revealed that the same mutation led to downstream modulation of kinase pathways that are linked to physiological responses such as fibrous tissue formation, apoptosis and cell proliferation.

17.
Clin Oral Investig ; 24(7): 2247-2257, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31650315

RESUMO

OBJECTIVES: To compare the root filling quality, the sealer extrusion, and the healing rates of apical lesions addressed via two endodontic treatment approaches. The hypothesis tested was that both techniques present similar apical periodontitis healing results. MATERIALS AND METHODS: This study was a parallel-design, pragmatic, and randomized clinical trial. One hundred twenty anterior teeth with necrotic pulps and apical periodontitis were randomly allocated to be either instrumented with hand files and obturated with the lateral compaction technique or instrumented with a single file in a reciprocating movement and obturated with a single-cone technique. The root canal filling quality, the occurrence of sealer extrusion, and apical periodontitis healing were the outcomes of interest. Data were analyzed through chi-square analysis, and the odds ratio for healing was adjusted using a logistic regression model (α = 0.05). RESULTS: No significant differences were observed between the endodontic techniques regarding the root filling quality or sealer extrusion. Six months after treatment, both endodontic techniques presented equivalent results regarding apical periodontitis healing. The healing rate was affected only by the periapical status at baseline. CONCLUSIONS: The obturation of the root canal of the anterior teeth using reciprocating file-matched single cones presented a similar quality to that obtained with manual instrumentation followed by the lateral condensation technique. Similar healing rates of apical lesions were also observed. CLINICAL RELEVANCE: For treating anterior teeth with apical periodontitis, a reciprocating single-file, single-treatment protocol was as effective as a traditional protocol combining hand instrumentation and the lateral compaction obturation technique.


Assuntos
Periodontite Periapical , Materiais Restauradores do Canal Radicular , Preparo de Canal Radicular , Humanos , Periodontite Periapical/terapia , Obturação do Canal Radicular , Tratamento do Canal Radicular
18.
Int J Biol Macromol ; 146: 141-149, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31857170

RESUMO

Recently, a salivary gland transcriptome study demonstrated that the transcripts of a putative cystatin gene (SeqID AAEL013287; Aacystatins) from Aedes aegypti were increased in DENV2-infected mosquitoes and that silencing of the Aacystatin gene resulted in an increase in DENV titres. In this work, Aacystatin was biochemically characterized; the purified recombinant inhibitor was able to inhibit typical cysteine proteases with a Ki in the nM range. Pulldown assays using Aag2 cell extracts identified a cathepsin L-like peptidase (AaCatL) as a possible target of Aacystatin. Purified recombinant AaCatL had an optimal pH of 5.0 and displayed a preference for Leu, Val and Phe residues at P2, which is common for other cathepsin L-like peptidases. Transcription analysis of Aacystatin and AaCatL in the salivary glands and midgut of DENV2-infected mosquitoes revealed a negative correlation between DENV2 titres and levels of the inhibitor and peptidase, suggesting their involvement in DENV2-mosquito interactions. Considering that apoptosis may play an important role during viral infections, the possible involvement of Aacystatin in staurosporine-induced apoptosis in Aag2 cells was investigated; the results showed higher expression of the inhibitor in treated cells; moreover, pre incubation with rAacystatin was able to increase Aag2 cell viability.


Assuntos
Aedes , Catepsina L , Cistatinas , Vírus da Dengue/metabolismo , Proteínas de Insetos , Aedes/enzimologia , Aedes/genética , Aedes/virologia , Animais , Catepsina L/química , Catepsina L/genética , Catepsina L/metabolismo , Linhagem Celular , Cistatinas/química , Cistatinas/genética , Cistatinas/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
19.
J Appl Polym Sci ; 136(25)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31736511

RESUMO

Thiourethane oligomers added to methacrylate matrices improve fracture toughness and reduce polymerization stress. In this study, the oligomers are added to the surface of inorganic fillers in the formulation of resin composites. Systematically varied fillers treated either with the thiourethane or a methacrylate silane control are tested. Thiourethane reduces the rate of polymerization of light-cured composites but does not affect the final degree of conversion (DC). Filler functionalization with thiourethane increases the depth of polymerization, in filler type-dependent fashion. Thiourethane reduces the polymerization stress for all fillers. The findings suggest that this approach results in the same general effects with the addition of thiourethanes directly to the matrix. This is accomplished with a lower overall concentration of thiourethane, and with no prejudice to the handling characteristics of the material.

20.
J Med Syst ; 43(10): 313, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31451942

RESUMO

Nowadays, smartphones represent an invaluable tool to access educational material; however, the available information is not always accurate or evidence-based. Therefore, we aimed to evaluate the use of technology by medical students and assess the effect of a newly developed mobile app for the study of human physiology. We used a standardised questionnaire to assess the profile of educational technology use, from which a mobile app (PhysioQuiz) was developed. The effectiveness and user opinion were assessed in a randomised controlled study (n = 110). Of 1022 students enrolled in medical school, 489 (47.9%) participated in the study. Of the respondents, 96.7% used mobile applications, with the main purpose being entertainment (94.7%) and study (81.9%). Only 6.1% reported use of physiology apps. PhysioQuiz use did not yield higher average grades (p = 0.48); however, user opinion demonstrated that it was useful for assisted learning (82.1%) and identification of non-learned content (78.6%) and considered a tool for self-assessment (89.3%). Mobile app use is widespread among medical students but there is a lack of human physiology education apps. A newly developed app for the study of human physiology was useful for assisted learning and considered a tool for self-assessment.


Assuntos
Educação Médica/métodos , Tecnologia Educacional , Aplicativos Móveis/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricos , Estudos Transversais , Humanos , Fisiologia/educação , Smartphone
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