RESUMO
The emergence and propagation of bacteria resistant to antimicrobial drugs is a serious public health threat worldwide. The current antibacterial arsenal is becoming obsolete and the pace of drug development is decreasing, highlighting the importance of investment in alternative approaches to treat or prevent infections caused by antimicrobial-resistant bacteria. A significant mechanism of antimicrobial resistance employed by Gram-negative bacteria is the overexpression of efflux pumps that can extrude several compounds from the bacteria, including antimicrobials. The overexpression of efflux pump proteins has been detected in several multidrug resistant (MDR) Gram-negative bacteria, drawing attention to these proteins as potential targets against these pathogens. This review will focus on the role of outer membrane proteins (OMPs) from efflux pumps as potential vaccine candidates against clinically relevant MDR Gram-negative bacteria, discussing advantages and pitfalls. Additionally, we will explore the relevance of efflux pump OMP diversity and the possible impact of vaccination on microbiota.
RESUMO
Growth measurements such as leaf area (LA) and dry matter (DM) are important in experiments about plants population, fertilization, irrigation and others parameters of cultivation, in garlic crop. The LA and DM are commonly defined as destructive, lengthy and cause loss of plants in the experimental units. The objective of this study was to fit mathematical models using linear models that estimate the leaf area and dry matter of garlic plants - variety Ito. For that, garlic plants were collected at 30, 45, 60, 75, 90, 115 and 120 days after planting. The measurements of width (W), length (L) of leaves, LA, DM, pseudostem diameter (PD), number of leaves per plant (NL) and height (H) were determined in each time. The models were fitted to estimate the LA or DM as function of the variables W, L, L*W, PD and LA. The statistical analysis of the linear regression, coefficient of determination of the linear regression (R2), root mean square error (RMSE), modified concordance index (d1) and the BIAS index were verified to determine the most representative models. It`s possible to estimate the LA and the leaf DM of garlic plants using the variables: length, width, pseudostem diameter and height of plants.
Medidas de crescimento como área foliar (AF) e matéria seca (MS) são importantes em experimentos com população de plantas, adubação, irrigação e outros parâmetros de cultivo, na cultura do alho. Muitas vezes a AF e MS são definidas por avaliações destrutivas, demoradas e com perdas de plantas nas unidades experimentais. Objetivou-se, com este trabalho, definir modelos matemáticos através de medidas lineares, que estimem a área foliar e a matéria seca das folhas de plantas de alho da variedade Ito. Para isso, quinze plantas foram coletadas aos 30, 45, 60, 75, 90, 115 e 120 dias após o plantio (DAP). As medidas de largura (L), comprimento (C) das folhas, AF, MS, diâmetro do pseudocaule (DP), número de folhas por planta (NF) e altura da planta (AP) foram determinadas em cada época. Ajustaram-se modelos para estimar a AF ou MS em função das variáveis L, C, L*C, DP e AF. Para determinar os modelos mais representativos foram verificados a análise estatística da regressão linear, o coeficiente de determinação da regressão linear (R2), raiz do quadrado médio do erro (RQME), índice de concordância modificado (d1) e o índice BIAS. É possível estimar a AF e MS foliar de plantas de alho através das variáveis comprimento, largura, diâmetro do pseudocaule e altura de plantas.
Assuntos
AlhoRESUMO
Este estudo in vitro objetivou avaliar o efeito erosivo de alguns refrigerantes sobre o esmalte dental humano. Para tanto, cinco refrigerantes diferentes, da marca Coca-Cola (Coca-Cola, Coca-Cola Zero, Sprite, Guaraná Kuat e Fanta Laranja) bem como 05 entes anteriores, obtidos por meio de doação (banco de dentes) foram utilizados. Inicialmente, os dentes tiveram a porção coronária separada da porção radicular com um auxílio de uma peça de mão reta em baixa velocidade e um disco diamantado duplo facetado. Em seguida, as porções coronárias foram seccionadas ao meio, obtendo-se 10 fragmentos, que foram divididos em: grupo controle (não exposto aos refrigerantes, n=05) e grupo experimental (n=05). Os valores pH dos refrigerantes foram determinados com o peagâmetro modelo pH300 marca ANALYSER, limpo e cheio com 3,0 mol. L-1 de KC1. Após isto, cada fragmento do grupo experimental foi imerso em 05 ml da solução de cada refrigerante por 10 min, sendo posteriormente lavados com 05 ml de água destilada. Os dados foram tratados por análise descritiva e avaliação em MEV. Os valores de pH para a Coca-Cola, da Coca-Cola Zero, do Sprite, do Guaraná Kuat e da Fanta Laranja, respectivamente foram: 2,76; 3,25; 3,25; 3,33 e 3,92. As imagens do MEV evidenciaram que a Coca-cola Zero, o Sprite e a Fanta Laranja alteraram a estrutura superficial do esmalte dental. Conclui-se que, embora todos os refrigerantes tenham apresentado pH inferior a 5,5, portanto potencialmente capazes de induzir a erosão, a Coca-Cola Zero causou maiores alterações superficiais no esmalte dental.
This in vitro study aimed to evaluate the erosive effect of some soft drinks on human enamel. To this, Coca-ColaTM, Coca-Cola ZeroTM, Sprite, Fanta flavor OrangeTM and Guarana KuatTM soft drinks were used. Five anterior teeth were obtained through tooth bank. Initially, the teeth were separated from the coronal portion of the root portion with a help of a straight handpiece at low speed and a Double-faceted diamond disc. Then, the coronal portions were sectioned in the middle, resulting in 10 fragments, which were divided into control group (not exposed to soft drinks) and experimental group (exposed to soft drinks). The pH of beverages were determined with the peagâmetro pH300 mode, ANALYSER brand, clean and filled with 3.0 mol. L-1 KC1. After that, each fragmento f the experimental group was immersed in 05 ml of soft drink for 10 min. After that, they were washed with 05 ml of distilled water. The data were evaluated by descriptive analysis and evaluation by SEM. The pH values for Coca-ColaTM, Coca-Cola ZeroTM, Sprite, Fanta flavor OrangeTM and Guarana KuatTM soft drinks respectively were: 2.76, 3.25, 3.25, 3.33 and 3.92. The SEM images showed that Coca-Cola ZeroTM Sprite and Fanta flavor orange have changed the surface structure of dental enamel. Although all drinks have submitted a pH below 5.5, thus potentially capable of induzing erosion Zero CokeTM caused more changes in the enamel surface.
