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OBJECTIVES: Picosecond lasers with a microlens array can cause laser-induced optical breakdown (LIOBS) and LIC (Intradermal laser-induced cavitation) within high-fluence areas. This study aimed to describe the clinical, reflectance confocal microscopy (RCM), histopathological findings, and the characteristics of vacuoles caused by LIOBS and LIC in individuals with skin types III and IV. MATERIALS AND METHODS: This study was performed on six Chilean healthy volunteers, males and females, aged 35-65 years old with Fitzpatrick skin phototypes III-IV. The laser was applied in the inner proximal area of the nondominant arm. RCM evaluation was performed 24 h later; 48 h later, skin biopsies were performed on the laser-treated areas. Clinical, histological, and RCM findings were recorded. RESULTS: Every individual developed a 10 mm2 area of clinical erythema in the treated area. Under RCM, all six volunteers had hyporeflective spherical structures at the level of the epidermis, consistent with intraepidermal vacuoles. Histopathological evaluation revealed different sizes of vacuoles in both the epidermis and dermis. CONCLUSION: The LIOBS and LIC processes and the secondary production of vacuoles could be highly valuable for effective dermal remodeling treatment and aid in promoting the production of new collagen, elastic fibers, and growth factors that could improve skin texture. These structures were visible under RCM and histopathological evaluation.

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Objetivo: Presentar dos casos de isquemia anastomótica tardía por bevacizumab y compararlo con la literatura actual. Casos clínicos: Se exponen dos pacientes con cáncer de recto metastásico, con manejo neoadyuvante, quirúrgico y adyuvancia que incluye bevacizumab, que presentan complicaciones isquémicas anastomóticas, evidenciadas con endoscopia, imágenes más biopsias dirigidas, resolviéndose en forma quirúrgica y biopsiando sitios perianastomóticos con cambios isquémicos. Discusión: Existe evidencia en la literatura que reporta isquemias y filtraciones anastomóticas tardías con el uso de bevacizumab. Parece prudente considerar y sospechar en forma oportuna esta complicación, especialmente, en pacientes con factores de riesgo. Conclusiones: Se debe considerar eventos isquémicos en territorios quirúrgicos, al uso de Bevacizumab. Mayor hincapié en pacientes con factores de riesgo como malnutrición, irradiación o sexo masculino. Considerar estudio dirigido anastomótico previo al inicio de bevacizumab. Dar relevancia a los tiempos de suspensión y reinicio de bevacizumab para evaluación de posibles complicaciones isquémicas.

Objective: To present two cases of late anastotomotic breakdown by bevacizumab and compare it with the current literature. Case report: Two patients with metastatic rectal cancer, with neoadjuvant, surgical and adjuvant management including bevacizumab, presenting anastomotic ischemic complications, evidenced with endoscopy, images and directed biopsies, surgically resolved and taking biopsy of perianastomotic sites with ischemic changes. Discussion: There is evidence in the literature reporting late anastomotic ischemia and leaks with the use of bevacizumab. It seems prudent to consider and suspect this complication in a timely manner, especially in patients with risk factors. Conclusions: Ischemic events in surgical territories should be considered when using bevacizumab. Greater emphasis on patients with risk factors such as malnutrition, irradiation or male sex. Anastomotic-directed study prior to initiation of bevacizumab should be considered. To highlight bevacizumab suspension and restart times for the evaluation of possible ischemic complications.

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This study was dedicated to developing analytical methods for determining macronutrients (Ca, K, and Mg) in soy leaf samples with and without petioles. The study's primary purpose was to present Laser-induced breakdown spectroscopy (LIBS) as a viable alternative for directly analyzing leaf samples using chemometric tools to interpret the data obtained. The instrumental condition chosen for LIBS was 70 mJ of laser pulse energy, 1.0 µs of delay time, and 100 µm of spot size, which was applied to 896 samples: 305 of soy without petioles and 591 of soy with petioles. The reference values of the analytes for the proposition of calibration models were obtained using inductively coupled plasma optical emission spectroscopy (ICP-OES) technique. Twelve normalization modes and two calibration strategies were tested to minimize signal variations and sample matrix microheterogeneity. The following were studied: multivariate calibration using partial least squares and univariate calibration using the area and height of several selected emission lines. The notable normalization mode for most models was the Euclidean norm. No analyte showed promising results for univariate calibrations. Micronutrients, P and S, were also tested, and no multivariate models presented satisfactory results. The models obtained for Ca, K, and Mg showed good results. The standard error of calibration ranged from 2.3 g/kg for Ca in soy leaves without petioles with two latent variables to 5.0 g/kg for K in soy leaves with petioles with two latent variables.

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RESUMEN El funcionamiento ecosistémico de quebradas o arroyos altoandinos de Colombia aún es poco conocido. El objetivo de este estudio fue evaluar la descomposición de hojas de aliso (Alnusacuminata), sietecueros (Andesanthuslepidotus) y una mezcla 1:1 de estas especies (Mixto), utilizando bolsas de hojarasca de poro amplio y fino, de 5 y 0,5 mm respectivamente, en la quebrada Las Perlas (2390 m.s.n.m.). Se recolectaron cuatro réplicas por tratamiento a los 3, 7, 15, 20 y 30 días, y se analizó la descomposición y la colonización por invertebrados (densidad, grupos funcionales de alimentación-GFA). Las tasas de descomposición (k) fueron significativamente distintas entre tratamientos y durante el experimento: A. acuminata (62 % de pérdida de masa seca) > Mixto (53 %) > A. lepidotus (31 %), principalmente en la primera semana y hacia el final del estudio. El mayor valor de k se registró en A. acuminata (- 0,019 días1) y el menor en A. lepidotus (- 0,004 días1). La densidad de macroinvertebrados colonizadores mostró una tendencia a aumentar durante el experimento, fue mayor en el día 20, y estuvo dominada principalmente por Diptera (Chironomidae, Simuliidae), Trichoptera (Hydroptilidae), Coleoptera (Elmidae) y Ephemeroptera (Leptohyphidae), mientras que en los GFA predominaron los recolectores, con los valores más altos en Mixto que en las especies por separado. En general, nuestros resultados sugieren que la colonización y la función de los invertebrados están relacionadas con la diversidad de hojas y sus mezclas, las cuales pueden definir la dinámica de la descomposición y de nutrientes en sistemas acuáticos tropicales altoandinos.

ABSTRACT The ecosystem functioning in headwater Colombian Andean streams is still poorly understood. The objective of this study was to evaluate the leaf decomposition of alder (Alnusacuminata), sietecueros (Andesanthus lepidotus) and a 1:1 mixture of the two species using coarse- (5 mm) and fine-mesh litter bags (0.5 mm) in the Las Perlas stream, a high-altitude tropical Andean aquatic system (2390 m.a.s.l.). A subset of 4-litterbags of each treatment was retrieved at 3, 7, 15, 20, and 30 days and analyzed for litter decomposition and invertebrate colonization (density, functional feeding groups-FFG). Decomposition rates (k) were significantly distinct between treatments and over the experiment: A. acuminata (62 % leaf dry mass loss) > Mixture (53 %) > A. lepidotus (31 %), mainly during the first week and toward the final phase of the study. The highest k-value was registered in A. acuminata (- 0.019 days1) and was lower in A. lepidotus (- 0.004 days1). Macroinvertebrate density tended to increase over the incubation period, was higher in the day 20, and was primarily dominated by Diptera (Chironomidae, Simuliidae), Trichoptera (Hydroptilidae), Coleoptera (Elmidae), and Ephemeroptera (Leptohyphidae), whereas the collectors predominated, attaining higher values in the Mixture than in the species alone. Overall, our results slightly suggest that invertebrate colonization and their function are related to the leaflitter diversity and mixing, which can define the dynamics of the decomposition and nutrients in tropical high-Andean aquatic systems.

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The knowledge about the effect of salinity on the physiological mechanism of bivalve reproduction is fundamental to improve production strategies in hatcheries. The present work evaluated the influence of different salinity concentrations (15, 20, 25, 30, 35 and 40 g⋅L-1) on pre- and post-fertilization development processes in the clam, Anomalocardia flexuosa, oocytes obtained by stripping. Salinity directly interfered with the germinal vesicle breakdown (GVBD) rate and in the cellular stability of unfertilized oocytes. Salinity concentrations between 30 and 35 g⋅L-1 provided better percentages of stable GVBD within 120 min, and incubation of oocytes in the salinity range of 30-35 g⋅L-1 for a time interval of 80-120 min provided > 80% GVBD. In the post-fertilization analysis, salinity affected the rate of the extrusion of the first and second polar bodies (PB1 and PB2). The release of 50% of the PBs was faster at a salinity of 35 g⋅L-1, with an estimated time of 10 min for PB1 and 30 min for PB2. Thus, chromosome manipulation methodologies aiming triploids should be applied at 35 g⋅L-1 salinity, with application of post-fertilization shock before 10 min for PB1 retention or before 30 min for PB2 retention.

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The contamination of aquatic environments with heavy metals is an important issue, and in turn, it is crucial to study remediation techniques that can be applied in situ. In this work, the use of a containment system with macrophytes Limnobium laevigatum is explored in the laboratory to evaluate the remotion of Cr in contaminated sediments. The roots of the plants were placed in contact with the bottom sediment through a containment system. The concentration of Cr in macrophyte and sediment samples exposed to different exposure times (1, 4 and 7 days) was determined by laser-induced breakdown spectroscopy technique. The initial concentration of Cr in the sediment was 112 ± 5 mg/kg and decreased by 65% to the control (p < 0.05) after 24 h of exposure. The removal continued throughout the study time until reaching values of 23 ± 1 mg/kg. In macrophytes, the Cr concentration increased from 20 ± 5 mg/kg to 2066 ± 216 mg/kg after seven days of exposure. The correlation coefficient between Cr concentrations in both matrices was -0.96. Finally, the bioaccumulation factor of Cr in L. laevigatum was 95.22 ± 8.51. Therefore, the system studied could be a potential tool to remedy the bottom sediments of streams and lakes contaminated with heavy metals in situ.

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The knowledge about the effect of salinity on the physiological mechanism of bivalve reproduction is fundamental to improve production strategies in hatcheries. The present work evaluated the influence of different salinity concentrations (15, 20, 25, 30, 35 and 40 g⋅L−1) on pre- and post-fertilization development processes in the clam, Anomalocardia flexuosa, oocytes obtained by stripping. Salinity directly interfered with the germinal vesicle breakdown (GVBD) rate and in the cellular stability of unfertilized oocytes. Salinity concentrations between 30 and 35 g⋅L−1 provided better percentages of stable GVBD within 120 min, and incubation of oocytes in the salinity range of 30-35 g⋅L−1 for a time interval of 80-120 min provided > 80% GVBD. In the post-fertilization analysis, salinity affected the rate of the extrusion of the first and second polar bodies (PB1 and PB2). The release of 50% of the PBs was faster at a salinity of 35 g⋅L−1, with an estimated time of 10 min for PB1 and 30 min for PB2. Thus, chromosome manipulation methodologies aiming triploids should be applied at 35 g⋅L−1 salinity, with application of post-fertilization shock before 10 min for PB1 retention or before 30 min for PB2 retention.(AU)

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Terrestrial leaf litter is an essential energy source in forest streams and in many tropical streams, including Cerrado, litter undergoes biological decomposition mainly by fungi. However, there is a limited understanding of the contribution of isolated fungal species to in-stream litter decomposition in the tropics. Here we set a full factorial microcosms experiment using four fungal species (Aquanectria penicillioides, Lunulospora curvula, Pestalotiopsis submerses, and Pestalotiopsis sp.) incubated in isolation, two litter types (rapid and slow decomposing litter) and two nutrient levels (natural and enriched), all characteristics of Cerrado streams, to elucidate the role of isolated fungal species on litter decomposition. We found that all fungal species promoted litter mass loss but with contributions that varied from 1% to 8% of the initial mass. The fungal species decomposed 1.5 times more the slow decomposing litter and water nutrient enrichment had no effect on their contribution to mass loss. In contrast, fungal biomass was reduced by nutrient enrichment and was different among fungal species. We showed fungal contribution to decomposition depends on fungal identity and litter type, but not on water nutrients. These findings suggest that the identity of fungal species and litter types may have more important repercussions to in-stream decomposition than moderate nutrient enrichment in the tropics.

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OBJETIVE: To evaluate all the available evidence assessing if in hypomineralized teeth, yellow-brownish opacities are more prone to post-eruptive breakdown (PEB) compared to white-creamy opacities. MATERIALS AND METHODS: Observational studies that evaluated the occurrence of PEB in hypomineralized teeth were considered for inclusion. Electronic searches were performed up to January 2022 in MedLine, LILACS, BBO, Cochrane Library, Web of Science, Scopus, and EMBASE. Neither publication date nor language restrictions were imposed to the searches. Two researchers independently performed the study selection, data extraction, and quality assessment of the included studies according to the Newcastle-Ottawa Scale (NOS). Datasets from studies were grouped for narrative synthesis based on the severity of the PEB (enamel or dentin), type of tooth (molar or incisor), unit of analysis (subject or tooth or tooth surface), and follow-up period (in months). The certainty of evidence was evaluated using the GRADE approach. RESULTS: Nine studies were included, five cohort and three cross-sectional. All studies assessed the opacities and PEB by visual examination and diagnosed MIH according to EAPD criteria. In the cohort studies, considering all follow-up periods (ranging from 6 to 36 months), dark opacities fractured more than light opacities, at both enamel and enamel/dentin levels, and molars fractured more than incisors. In two out of three cross-sectional studies, dark opacities also fractured more than light opacities, but the deep of the PEB (enamel or dentin breakdown) or the type of tooth (molar or incisor) was not considered in the analysis. CONCLUSION: Although it seems plausible to state that darker demarcated opacities in MIH patients broke more often than light ones, based on this systematic review of the literature, the certainty of the available evidence about this association is still very low. CLINICAL RELEVANCE: More reliable and valid research is still necessary to support any future recommendation that MIH children who present yellow-brownish opacities should be monitored at shorter intervals compared to those who present only white-creamy opacities.

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The effect of different bolus sizes on food breakdown has been studied in adults, but not in children. The objective of this study was to study median particle size (MPS) and other parameters of masticatory function at swallowing threshold (ST) in 8-10-year-old-children with two different bolus sizes. A randomized crossover trial was undertaken in 89 eight to ten-year-old children. The study was performed with informed consent and ethical approval. The artificial test food used was made of a condensation silicone (Optosil Comfort) following a standardized protocol. Two bolus sizes (three or four quarters of a 20-mm diameter, 5-mm thick tablet) were randomized to avoid an order effect and tested in different sessions. Variables were: MPS (X50 ) at ST, number of cycles until ST, sequence and cycle duration as well as cycles/g. Comparisons were performed with paired t and Wilcoxon tests, regressions and correlations were run. Cutoff for statistical significance was .05. Statistically significant differences were found for all variables; X50 (2.5 ± 0.8 vs. 2.8 ± 0.7 mm, p < .001), cycles until ST (38 vs. 40, p = .022), sequence (25 vs. 27 s, p = .003), and cycle duration (650 vs. 683 ms, p = .015) and cycles/g (27 vs. 21 cycles/g, p < .001), three or four quarters, respectively. In conclusion, in children, as in adults, chewing on a bigger bolus size leads to a larger MPS (X50 ) at ST. When chewing on a larger bolus the number of cycles increases, but not enough to swallow the same particle size since the number of cycles/g is less with a bigger bolus size.

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This paper describes the effects of laser pulse rate and solution flow rate on the determination of lithium at high pressure for water and 2.5% sodium chloride solutions using laser-induced breakdown spectroscopy (LIBS). Preliminary studies were performed with 0-40 mg L-1 Li solutions, at ambient pressure and at 210 bar, and in static and flowing (6 mL · min-1) regimes, for a combination of four different measurement conditions. The sensitivity of calibration curves depended on the pressure and the flow rate, as well as the laser pulse rate. The sensitivity of the calibration curve increased about 10% and 18% when the pressure was changed from 1 to 210 bar for static and flowing conditions, respectively. However, an effect of flow rate at high pressure for both 2 and 10 Hz laser pulse rates was observed. At ambient pressure, the effect of flow rate was negligible, as the sensitivity of the calibration curve decreased around 2%, while at high pressure the sensitivity increased around 4% when measurements were performed in a flow regime. Therefore, it seems there is a synergistic effect between pressure and flow rate, as the sensitivity increases significantly when both changes are considered. When the pulse rate is changed from 2 to 10 Hz, the sensitivity increases 26-31%, depending on the pressure and flow conditions. For lithium detection limit studies, performed with a laser pulse energy of 2.5 mJ, repetition rate of 10 Hz, gate delay of 500 ns, gate width of 1000 ns, and 1000 accumulations, a value around 40 µg L-1 was achieved for Li solutions in pure water for all four measurement conditions, while a detection limit of about 92 µg L-1 was determined for Li in 2.5% sodium chloride solutions, when high pressure and flowing conditions were employed. The results obtained in the present work demonstrate that LIBS is a powerful tool for the determination of Li in deep ocean conditions such as those found around hydrothermal vent systems.

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AIMS: Although it is well established that skeletal muscle contains oxytocin (OT) receptors and OT-knockout mice show premature development of sarcopenia, the role of OT in controlling skeletal muscle mass is still unknown. Therefore, the present work aimed to determine OT's effects on skeletal muscle protein metabolism. MAIN METHODS: Total proteolysis, proteolytic system activities and protein synthesis were assessed in isolated soleus muscle from prepubertal female rats. Through in vivo experiments, rats received 3-day OT treatment (3UI.kg-1.day-1, i.p.) or saline, and muscles were harvested for mass-gain assessment. KEY FINDINGS: In vitro OT receptor stimulation reduced total proteolysis, specifically through attenuation of the lysosomal and proteasomal proteolytic systems, and in parallel activated the Akt/FoxO1 signaling and suppressed atrogenes (e.g., MuRF-1 and atrogin-1) expression induced by motor denervation. On the other hand, the protein synthesis was not altered by in vitro treatment with the OT receptor-selective agonist. Although short-term OT treatment did not change the atrogene mRNA levels, the protein synthesis was stimulated, resulting in soleus mass gain, probably through an indirect effect. SIGNIFICANCE: Taken together, these data show for the first time that OT directly inhibits the proteolytic activities of the lysosomal and proteasomal systems in rat oxidative skeletal muscle by suppressing atrogene expression via stimulation of Akt/FoxO signaling. Moreover, the data obtained from in vivo experiments suggest OT's ability to control rat oxidative skeletal muscle mass.

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The correct recognition of sweet orange (Citrus sinensis L. Osbeck) variety accessions at the nursery stage of growth is a challenge for the productive sector as they do not show any difference in phenotype traits. Furthermore, there is no DNA marker able to distinguish orange accessions within a variety due to their narrow genetic trace. As different combinations of canopy and rootstock affect the uptake of elements from soil, each accession features a typical elemental concentration in the leaves. Thus, the main aim of this work was to analyze two sets of ten different accessions of very close genetic characters of three varieties of fresh citrus leaves at the nursery stage of growth by measuring the differences in elemental concentration by laser-induced breakdown spectroscopy (LIBS). The accessions were discriminated by both principal component analysis (PCA) and a classifier based on the combination of classification via regression (CVR) and partial least square regression (PLSR) models, which used the elemental concentrations measured by LIBS as input data. A correct classification of 95.1% and 80.96% was achieved, respectively, for set 1 and set 2. These results showed that LIBS is a valuable technique to discriminate among citrus accessions, which can be applied in the productive sector as an excellent cost-benefit tool in citrus breeding programs.

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BACKGROUND: The filamentous fungus Trichoderma reesei is used on an industrial scale to produce enzymes of biotechnological interest. This fungus has a complex cellulolytic system involved in the degradation of lignocellulosic biomass. However, several aspects related to the regulation of the expression of holocellulolytic genes and the production of cellulases by this fungus are still understood. METHODS: Here, we constructed a null mutant strain for the xyloglucanase cel74a gene and performed the characterization of the Δcel74a strain to evaluate the genetic regulation of the holocellulases during sugarcane bagasse (SCB) cultivation. RESULTS: Our results demonstrate that the deletion of xyloglucanase cel74a may impact the regulation of holocellulase expression during SCB cultivation. The expression of cellulases cel7a, cel7b, and cel6a was reduced in Δcel74a strain, while the hemicellulases xyn1 and xyn2 were increased in the presence of SCB. The cel74a mutation also affected the xyloglucan hydrolysis patterns. In addition, CEL74A activity was modulated in the presence of calcium, suggesting that this ion may be required for efficient degradation of xyloglucan. CONCLUSIONS: CEL74A affects the regulation of holocellulolytic genes and the efficient degradation of SCB in T. reesei. This data makes a significant contribution to our understanding of the carbon utilization of fungal strains as a whole.

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The branching ratio method is usually used to evaluate the optical thinness conditions in laser-generated plasmas, which are important for the application of analytical methods such calibration free laser induced breakdown spectroscopy (CF-LIBS). In this communication, we warn on the possibility that in some circumstances, the branching-ratio method might give results close to the one characterizing optically thin plasma conditions, even in the presence of a substantial self-absorption for the transitions considered.

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Pottery sherds from Teotihuacan, Mexico, belonging to the Formative and Classic periods (150 BCE-700 CE) were investigated using laser-induced breakdown spectroscopy (LIBS) and inductively coupled plasma optical emission spectrometry (ICP-OES). LIBS results show that most of the investigated samples have primarily the same elemental composition. Nevertheless, there are also a few sherds that could be associated to foreign ceramic groups with characteristic concentrations of Na, K, Ca, Mn, Rb, and Sr. The relative elemental composition of red pigments applied on ceramic bodies was also analyzed through a LIBS depth profiling. Diverse hematite-based pigments were distinguished according to the detected iron content. Hematite was also combined with red soils with a high relative content of Mn, Sr, Ba, or Ti. The ICP-OES analysis of ceramic pastes is consistent with the emission intensities obtained using LIBS. Principal component analysis indicates that all samples identified as locals belong to a single chemical group. Moreover, locally made ceramics and the analyzed clays from the nearby area have the same elemental composition, which appears clearly differentiated from imported samples.

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Abstract Xanthomonas oryzae pv. oryzae (Xoo), a pathogen responsible for rice bacterial leaf blight, produces biofilm to protect viable Xoo cells from antimicrobial agents. A study was conducted to determine the potency of Acacia mangium methanol (AMMH) leaf extract as a Xoo biofilm inhibitor. Four concentrations (3.13, 6.25, 9.38, and 12.5 mg/mL) of AMMH leaf extract were tested for their ability to inhibit Xoo biofilm formation on a 96-well microtiter plate. The results showed that the negative controls had the highest O.D. values from other treatments, indicating the intense formation of biofilm. This was followed by the positive control (Streptomycin sulfate, 0.2 mg/mL) and AMMH leaf extract at concentration 3.13 mg/mL, which showed no significant differences in their O.D. values (1.96 and 1.57, respectively). All other treatments at concentrations of 6.25, 9.38, and 12.5 mg/mL showed no significant differences in their O.D. values (0.91, 0.79, and 0.53, respectively). For inhibition percentages, treatment with concentration 12.5 mg/mL gave the highest result (81.25%) followed by treatment at concentrations 6.25 and 9.38 mg/mL that showed no significant differences in their inhibition percentage (67.75% and 72.23%, respectively). Concentration 3.13 mg/mL resulted in 44.49% of biofilm inhibition and the positive control resulted in 30.75% of biofilm inhibition. Confocal laser scanning microscopy (CLSM) analysis of Xoo biofilm inhibition and breakdown showed the presence of non-viable Xoo cells and changes in aggregation size due to increase in AMMH leaf extract concentration. Control slides showed the absence of Xoo dead cells.

Resumo Xanthomonas oryzae pv. oryzae (Xoo), um patogênico responsável pela influência bacteriana na folha do arroz, produz biofilme para proteger células Xoo viáveis de agentes antimicrobianos. Foi conduzido um estudo para determinar a potência do extrato de folha de Acacia mangium methanol (AMMH) como um inibidor de biofilme Xoo. Quatro concentrações (3,13, 6,25, 9,38 e 12,5 mg/mL) de extrato de folha de AMMH foram testadas quanto à sua capacidade de inibir a formação de biofilme Xoo em uma placa de microtitulação de 96 poços. Os resultados mostraram que os controles negativos tiveram o maior valor de OD do que os outros tratamentos, indicando a intensa formação de biofilme. Isso foi seguido do controle positivo (sulfato de estreptomicina, com concentração de 0,2 mg/mL, e extrato de folha de AMMH, com concentração de 3,13 mg/mL), que não apresentou diferenças significativas nos seus valores OD (1,96 e 1,57, respectivamente). Todos os outros tratamentos com concentrações de 6,25, 9,38, e 12,5 mg/mL não tiveram diferenças significativas nos seus valores OD (0,91, 0,79, e 0,53, respectivamente). Para percentagens de inibição, o tratamento com concentração 12,5 mg/mL apresentou o maior resultado (81,25%), seguido do tratamento em concentrações de 6,25 e 9,38 mg/mL, que não mostraram diferenças significativas na sua percentagem de inibição (67,75 e 72,23%, respectivamente). Concentração 3,13 mg/mL resultou em 44,49% de inibição do biofilme, e o controle positivo resultou em 30,75% de inibição do biofilme. Análise por microscopia confocal de leitura a laser de inibição e separação de biofilme Xoo revelou a presença de células Xoo não viáveis e alterações no tamanho da agregação por causa do aumento na concentração de extrato de folha de AMMH. Slides de controle mostraram a ausência de células Xoo mortas.

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Xanthomonas oryzae pv. oryzae (Xoo), a pathogen responsible for rice bacterial leaf blight, produces biofilm to protect viable Xoo cells from antimicrobial agents. A study was conducted to determine the potency of Acacia mangium methanol (AMMH) leaf extract as a Xoo biofilm inhibitor. Four concentrations (3.13, 6.25, 9.38, and 12.5 mg/mL) of AMMH leaf extract were tested for their ability to inhibit Xoo biofilm formation on a 96-well microtiter plate. The results showed that the negative controls had the highest O.D. values from other treatments, indicating the intense formation of biofilm. This was followed by the positive control (Streptomycin sulfate, 0.2 mg/mL) and AMMH leaf extract at concentration 3.13 mg/mL, which showed no significant differences in their O.D. values (1.96 and 1.57, respectively). All other treatments at concentrations of 6.25, 9.38, and 12.5 mg/mL showed no significant differences in their O.D. values (0.91, 0.79, and 0.53, respectively). For inhibition percentages, treatment with concentration 12.5 mg/mL gave the highest result (81.25%) followed by treatment at concentrations 6.25 and 9.38 mg/mL that showed no significant differences in their inhibition percentage (67.75% and 72.23%, respectively). Concentration 3.13 mg/mL resulted in 44.49% of biofilm inhibition and the positive control resulted in 30.75% of biofilm inhibition. Confocal laser scanning microscopy (CLSM) analysis of Xoo biofilm inhibition and breakdown showed the presence of non-viable Xoo cells and changes in aggregation size due to increase in AMMH leaf extract concentration. Control slides showed the absence of Xoo dead cells.(AU)

Xanthomonas oryzae pv. oryzae (Xoo), um patogênico responsável pela influência bacteriana na folha do arroz, produz biofilme para proteger células Xoo viáveis de agentes antimicrobianos. Foi conduzido um estudo para determinar a potência do extrato de folha de Acacia mangium methanol (AMMH) como um inibidor de biofilme Xoo. Quatro concentrações (3,13, 6,25, 9,38 e 12,5 mg/mL) de extrato de folha de AMMH foram testadas quanto à sua capacidade de inibir a formação de biofilme Xoo em uma placa de microtitulação de 96 poços. Os resultados mostraram que os controles negativos tiveram o maior valor de OD do que os outros tratamentos, indicando a intensa formação de biofilme. Isso foi seguido do controle positivo (sulfato de estreptomicina, com concentração de 0,2 mg/mL, e extrato de folha de AMMH, com concentração de 3,13 mg/mL), que não apresentou diferenças significativas nos seus valores OD (1,96 e 1,57, respectivamente). Todos os outros tratamentos com concentrações de 6,25, 9,38, e 12,5 mg/mL não tiveram diferenças significativas nos seus valores OD (0,91, 0,79, e 0,53, respectivamente). Para percentagens de inibição, o tratamento com concentração 12,5 mg/mL apresentou o maior resultado (81,25%), seguido do tratamento em concentrações de 6,25 e 9,38 mg/mL, que não mostraram diferenças significativas na sua percentagem de inibição (67,75 e 72,23%, respectivamente). Concentração 3,13 mg/mL resultou em 44,49% de inibição do biofilme, e o controle positivo resultou em 30,75% de inibição do biofilme. Análise por microscopia confocal de leitura a laser de inibição e separação de biofilme Xoo revelou a presença de células Xoo não viáveis e alterações no tamanho da agregação por causa do aumento na concentração de extrato de folha de AMMH. Slides de controle mostraram a ausência de células Xoo mortas.(AU)

Assuntos

RESUMO

Lipid droplets (LD) have long been considered as mere fat drops; however, LD have lately been revealed to be ubiquitous, dynamic and to be present in diverse organelles in which they have a wide range of key functions. Although incompletely understood, the biogenesis of eukaryotic LD initiates with the synthesis of neutral lipids (NL) by enzymes located in the endoplasmic reticulum (ER). The accumulation of NL leads to their segregation into nanometric nuclei which then grow into lenses between the ER leaflets as they are further filled with NL. The lipid composition and interfacial tensions of both ER and the lenses modulate their shape which, together with specific ER proteins, determine the proneness of LD to bud from the ER toward the cytoplasm. The most important function of LD is the buffering of energy. But far beyond this, LD are actively integrated into physiological processes, such as lipid metabolism, control of protein homeostasis, sequestration of toxic lipid metabolic intermediates, protection from stress, and proliferation of tumours. Besides, LD may serve as platforms for pathogen replication and defense. To accomplish these functions, from biogenesis to breakdown, eukaryotic LD have developed mechanisms to travel within the cytoplasm and to establish contact with other organelles. When nutrient deprivation occurs, LD undergo breakdown (lipolysis), which begins with the LD-associated members of the perilipins family PLIN2 and PLIN3 chaperone-mediated autophagy degradation (CMA), a specific type of autophagy that selectively degrades a subset of cytosolic proteins in lysosomes. Indeed, PLINs CMA degradation is a prerequisite for further true lipolysis, which occurs via cytosolic lipases or by lysosome luminal lipases when autophagosomes engulf portions of LD and target them to lysosomes. LD play a crucial role in several pathophysiological processes. Increased accumulation of LD in non-adipose cells is commonly observed in numerous infectious diseases caused by intracellular pathogens including viral, bacterial, and parasite infections, and is gradually recognized as a prominent characteristic in a variety of cancers. This review discusses current evidence related to the modulation of LD biogenesis and breakdown caused by intracellular pathogens and cancer.

RESUMO

In this study, hybrid poly(dimethylsiloxane)-derived hydroxyurethanes films (PDMSUr-PWA) containing phosphotungstic acid (H3PW12O40/PWA) were characterized using field emission gun scanning electron microscopy (FEG-SEM), in attenuated total reflectance Fourier transform mid-infrared mode (ATR FT-MIR), and analyzed using synchrotron radiation micro-X-ray fluorescence (SR-µXRF), synchrotron radiation grazing incidence X-ray fluorescence (SR-GIXRF), laser-induced breakdown spectroscopy (LIBS), and instrumental neutron activation analysis (NAA) in order to correlate the distribution patterns of tungsten and properties of PDMSUr-PWA films. PDMS constitute elastomers with good mechanical, thermal, and chemical (hydrophobicity/non-hygroscopy) resistance. Currently, products based on urethanes (e.g., polyurethanes) are widely used in many applications as plastics, fiber-reinforced polymers, high-performance adhesives, corrosion-resistant coatings, photochromic films, among others. The possibility to combine inorganic and organic components can produce a hybrid material with unique properties. PWA has an important role as agent against the corrosion of steel surfaces in different media, besides exhibiting amazing catalytic and photochromic properties in these films. PWA kept its structure inside of these hybrid films through interactions between the organic matrix of PDMSUr and silanol from the inorganic part (organically modified silica), as was shown using ATR FT-MIR spectra. The FEG-SEM/SR-µXRF/wide-angle X-ray scattering (WAXS)/X-ray diffraction (XRD)/energy dispersive X-ray results proved the presence of PWA in the composition of domains of PDMSUr-PWA films. At PWA concentrations higher than 50 wt%/wt, tungsten segregation across the thickness is predominant, while that at PWA concentrations lower than 35 wt%/wt, tungsten segregation at surface is predominant. Inhomogeneities in the tungsten distribution patterns (at micrometric and millimetric level) may play an important role in the mechanical properties of these films (elastic modulus and hardness).