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1.
Chaos ; 33(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38060771

RESUMEN

The E×B drift motion of particles in tokamaks provides valuable information on the turbulence-driven anomalous transport. One of the characteristic features of the drift motion dynamics is the presence of chaotic orbits for which the guiding center can experience large-scale drifts. If one or more exits are placed so that they intercept chaotic orbits, the corresponding escape basins structure is complicated and, indeed, exhibits fractal structures. We investigate those structures through a number of numerical diagnostics, tailored to quantify the final-state uncertainty related to the fractal escape basins. We estimate the escape basin boundary dimension through the uncertainty exponent method and quantify final-state uncertainty by the basin entropy and the basin boundary entropy. Finally, we recall the Wada property for the case of three or more escape basins. This property is verified both qualitatively and quantitatively using a grid approach.

2.
Int Endod J ; 52(1): 5-12, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29904933

RESUMEN

AIM: To investigate the DNA methylation profiles of immune response-related genes in apical periodontitis (AP) lesions. METHODOLOGY: The methylation profiles on the cytosine-phosphate-guanine (CpG) regions of 22 gene promoters involved in inflammation and autoimmunity were assessed in 60 human AP lesions and 24 healthy periodontal ligaments (controls) using a pathway-specific real-time polymerase chain reaction array (EpiTect® Methyl Signature PCR Array Human Inflammatory Response). Differentially methylated genes were subsequently assessed for their mRNA expression. Data analyses (One-way anova, Tukey's multiple comparisons tests and Mann-Whitney tests) were performed using GraphPad Prism 6 software. P values ≤ 0.05 were considered statistically significant. RESULTS: Significant DNA hypermethylation was observed for CXCL3 and FADD gene promoters in AP lesions when compared to control tissues (P < 0.001) and among other genes (P < 0.05). In contrast, IL12B and IL4R were associated with significant hypomethylation in comparison to other genes (P < 0.05). IL12B, IL4R, CXCL3 and FADD had differential mRNA expression in AP lesions and controls (P < 0.001). CONCLUSIONS: Differential methylation profiles of immune response-related genes, such as FADD, CXCL3, IL12B and IL4R, may have an influence on individual AP susceptibility and patient treatment outcomes, through their potential contributions to altered expression of disease-relevant genes. Methylation and/or genetic variations in additional genes may also contribute to the dynamics of AP development and should be considered in future studies.


Asunto(s)
Metilación de ADN , Periodontitis Periapical/genética , Periodontitis Periapical/inmunología , Periodontitis Periapical/metabolismo , Transcriptoma , Adolescente , Adulto , Anciano , Autoinmunidad/genética , Brasil , Quimiocinas/genética , Quimiocinas CXC/genética , Citocinas/genética , Proteína de Dominio de Muerte Asociada a Fas/genética , Regulación de la Expresión Génica , Humanos , Inflamación , Subunidad p40 de la Interleucina-12/genética , Subunidad alfa del Receptor de Interleucina-4/genética , Persona de Mediana Edad , Ligamento Periodontal , Regiones Promotoras Genéticas , ARN Mensajero/biosíntesis , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Citocinas/genética , Adulto Joven
3.
Int Endod J ; 52(9): 1344-1353, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31025362

RESUMEN

AIM: To investigate the expression of TP63 in apical periodontitis (AP) tissues and the association of single nucleotide polymorphisms (SNPs) in the TP63 gene with AP using a case-control dataset. METHODOLOGY: Expression of TP63 in human AP lesions (apical abscess, radicular cyst, periapical granuloma) was evaluated using immunohistochemistry. A case-control association study was performed to assess the association of TP63 polymorphisms in individuals having AP with or without associated pain. Cases were defined as subjects with deep caries and AP (n = 151) and subjects with symptomatic apical periodontitis or acute apical abscess (n = 124). Subjects without AP (n = 169) and asymptomatic (n = 196) were used as controls, respectively. Saliva samples were collected as source of genomic DNA. Twelve SNPs in the TP63 gene were selected for genotyping using Taqman chemistry in real-time PCR. Data analysis was performed using PLINK software. The Bonferroni method was applied to correct for multiple testing; α ≤ 0.004 indicates significant differences between groups. RESULTS: TP63 expression was evident in apical abscesses and radicular cysts, while weaker expression was observed in periapical granulomas. Positive expression was observed in mononuclear cells in the granulation tissues of all AP lesions. Regarding the presence of AP, a trend for allelic association was observed for rs16864812 and rs9810322 (P = 0.04) and rs9810322 genotypes were also nominally associated with AP under a dominant model (P = 0.04). When considering the presence of periapical pain, a trend for allelic and genotypic association was observed for rs10155037 (P = 0.03). Haplotypes were also associated with AP and periapical pain (P ≤ 0.05). CONCLUSIONS: Apical periodontitis is a complex multifactorial condition and it is likely that multiple genes and environmental effects may influence its susceptibility, progression or both. TP63 variants may play a role in AP pathogenesis and susceptibility, individually or interactively with other genes. Additional studies in other populations and functional studies are needed to improve understanding of the role of TP63 in AP.


Asunto(s)
Absceso Periapical , Granuloma Periapical , Periodontitis Periapical , Quiste Radicular , Humanos , Polimorfismo de Nucleótido Simple , Factores de Transcripción , Proteínas Supresoras de Tumor
4.
J Intellect Disabil Res ; 63(11): 1379-1389, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30900361

RESUMEN

BACKGROUND: The chromosomal microarray analysis (CMA) is recommended as a first-tier test for individuals with developmental delay (DD)/intellectual disability (ID) and/or multiple congenital anomalies. However, owing to high costs, this technique is not widely performed for diagnostic purposes in several countries. The aim of this study was to identify clinical features that could favour the hypothesis of genomic imbalances (GIs) in individuals with DD/ID. METHODS: The sample consisted of 63 individuals, and all of them underwent a detailed evaluation by a clinical geneticist and were investigated by the CMA. They were divided into two groups. Group A composed of 20 individuals with pathogenic copy number variants (CNVs); and group B composed of 43 individuals with normal CMA results or variants of uncertain clinical significance (VUS). RESULTS: Pathogenic GIs were found in 20 cases (32%), including 11 individuals with an abnormal karyotype, VUS was found in five individuals (8%) and the results were normal in 38 individuals (60%). Major anomalies were found in 15/20 (75%) individuals in group A against 35/43 (81%) in group B. Dysmorphisms (≥5) were found in 17/20 (85%) in group A and 41/43 (95%) in group B. The most frequent major anomalies detected in group A were congenital heart disease, epilepsy and renal malformation; and in group B, they were malformations of central nervous system, congenital heart disease, microcephaly, epilepsy and hearing impairment. There was no significant statistical difference among the frequencies in groups A and B. CONCLUSIONS: Evidences point that every individual with DD/ID, with no specific clinical suspicion, should have screening for GIs as a first-tier test, regardless of the presence or absence of additional major anomalies or dysmorphisms. Future studies with a similar design would be helpful, especially in countries where the access to new technologies is still limited.


Asunto(s)
Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/genética , Variación Estructural del Genoma/genética , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Fenotipo , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Análisis por Micromatrices , Adulto Joven
5.
Genet Mol Res ; 16(3)2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28973753

RESUMEN

Schizolobium parahyba var. amazonicum (Fabaceae) is an arboreal species, endemic to the Amazon Rainforest, popularly known as paricá. It is used on a commercial scale in the timber sector, pulp and paper production, reclamation projects in degraded and landscaped areas. However, there is no availability of genetically improved material selected for the environmental conditions of the State of Espírito Santo, Brazil. In this sense, the present study aimed to characterize the genetic diversity in a population of S. amazonicum, established in a forest area in the southern region of the State of Espírito Santo, using inter-simple sequence repeat (ISSR) molecular markers. DNA samples from 171 individuals were analyzed using 11 ISSR primers, which generated 79 polymorphic bands in a total of 136 fragments (58%). The polymorphic information content performed for the ISSR markers revealed a mean of 0.37, classifying them as moderately informative. The number of loci found (N = 79) was greater than that established as the optimal number (N = 69) for the analyses. High genetic diversity was found with the parameters, genetic diversity of Nei (HE = 0.375) and Shannon index (I = 0.554). The data demonstrated in the dendrogram, based on the UPGMA cluster analysis, corroborated by the Bayesian analysis performed by the STRUCTURE program, which indicated the formation of two distinct clusters (K = 2). One of the groups was formed with the majority of the individuals (153 genotypes) and the second with the minority (18 genotypes). The results revealed high genetic diversity in the population of S. amazonicum evaluated in the present study, determining the potential of the population to be used as an orchard for seed collection and production of seedlings with confirmed genetic variability.


Asunto(s)
Fabaceae/genética , Polimorfismo Genético , Brasil , Bosques , Repeticiones de Microsatélite
6.
Genet Mol Res ; 16(3)2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-28973754

RESUMEN

Studies of genetic diversity in natural populations are important for the definition of conservation strategies, especially in populations reduced by processes of fragmentation and continuous forest extraction. Molecular markers stand out as interesting tools for these studies. The objective of this research was to characterize the diversity and genetic structure of Plathymenia reticulata (Fabaceae), occurring in two fragments of the Montana Semideciduous Forest in the southern of Espírito Santo State, Brazil, using inter-simple sequence repeat (ISSR) molecular markers. DNA samples from 149 individuals were analyzed using 10 ISSR primers, generating 156 fragments, of which 101 were polymorphic (64.74%). The individuals sampled were classified into three units: adult trees (A), a mixture of progenies (B), and young regenerating individuals (C). The number of loci used (N = 101) was greater than that established as optimal number (N = 88), indicating precision in analyses. The genetic diversity index of Nei (H' = 0.407) and the Shannon index (I = 0.594) were found to have high genetic diversity. Besides, through the diversity parameters evaluated, it was possible to confirm that in the areas of natural regeneration and progeny mix there is genetic diversity equivalent to that found in adults. The analysis of molecular variance indicated that most of the genetic variation is found within the groups (96.53%). Genetic differentiation among adult trees was low (ΦST = 0.03) indicating that high gene flow rates (Nm = 12.70) are counteracting the effects of genetic drift. The data obtained allowed to evaluate the potential of adult trees as matrices for seed collection and to obtain seedlings with confirmed genetic variability.


Asunto(s)
Fabaceae/genética , Polimorfismo Genético , Brasil , Bosques , Repeticiones de Microsatélite
7.
Int Endod J ; 47(8): 769-75, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24246167

RESUMEN

AIM: To evaluate the cytotoxic effects of triple antibiotic paste (TAP), double antibiotic paste (DAP), minocycline and calcium hydroxide and their influence on cytokine mRNA expression levels on human periodontal ligament (HPDL) fibroblasts. METHODOLOGY: Triple antibiotic paste, DAP and Ca(OH)2 test samples were immersed in culture medium and incubated at 37 °C for 24 and 48 h. HPDL cells were seeded at a density of 2 × 10(4) cells and exposed to either culture media (negative control), 0.1% SDS (positive control), 24- or 48-h elutes of each test material and incubated for 24 h. A multiparametric cytotoxicity assay kit (XTT, NR and CVDE) was used to evaluate the cytotoxic effects of each test material. Results were analysed using an ELISA plate reader and light absorbances of 450 and 530 nm as references. Cytokine mRNA expression levels in HPDL cells treated with the materials were also investigated using real-time PCR. Expression levels were calculated using the comparative 2(-ΔΔCt) method. Statistical analyses included anova followed by Bonferroni correction. RESULTS: Triple antibiotic paste and minocycline were the most cytotoxic materials when compared with DAP and Ca(OH)2 in all three (XTT, NR and CVDE) assays (P < 0.0001). No significant differences (P > 0.05) were found for cytokine gene expression levels after exposure to 24- or 48-h elutes of any of the materials except for IL6, which had significantly higher mRNA levels with the 24-h TAP elute (P < 0.01). CONCLUSION: Ca(OH)2 had a minimal effect on cell viability and cytokine production. The TAP showed deleterious effects on HPDL viability and increased expression of the pro-inflammatory cytokine IL6.


Asunto(s)
Antibacterianos/farmacología , Ligamento Periodontal/efectos de los fármacos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Fibroblastos/efectos de los fármacos , Humanos , Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , ARN Mensajero/genética
8.
Phys Rev E ; 109(1-2): 015202, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38366399

RESUMEN

We investigate chaotic impurity transport in toroidal fusion plasmas (tokamaks) from the point of view of passive advection of charged particles due to E×B drift motion. We use realistic tokamak profiles for electric and magnetic fields as well as toroidal rotation effects, and consider also the effects of electrostatic fluctuations due to drift instabilities on particle motion. A time-dependent one degree-of-freedom Hamiltonian system is obtained and numerically investigated through a symplectic map in a Poincaré surface of section. We show that the chaotic transport in the outer plasma region is influenced by fractal structures that are described in topological and metric point of views. Moreover, the existence of a hierarchical structure of islands-around-islands, where the particles experience the stickiness effect, is demonstrated using a recurrence-based approach.

9.
Braz J Biol ; 84: e281457, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38896729

RESUMEN

Cowpea is a leguminous plant belonging to the fabaceae family cultivated in the North and Northeast regions of Brazil, with productive potential. Among the abiotic factors, water deficiency is one of the main environmental limitations that influence agricultural production in the world. The objective of this work was to study the relative water content and osmoregulators of cowpea plants subjected to water stress. The experiment was carried out in a greenhouse at the Universidade Federal Rural da Amazônia (UFRA, Belém, PA), cowpea plants BR-17 Gurguéia Vigna unguiculata (L.) Walp were used. The experimental design was completely randomized (DIC) in a 2 × 2 factorial scheme, two water conditions (control and water deficit) and two times of stress (four and six days of water suspension), with 7 replications, totaling 28 experimental units. The water deficit affected plants, causing a reduction in relative water content (69.98%), starch (12.84% in leaves and 23.48% in roots) and carbohydrates (84.34%), and an increase in glycine-betaine, sucrose (114.11% in leaves and 18.71% in roots) and proline (358.86%) at time 2. The relative water content was negatively affected by water conditions, with a decrease in relation to the interaction of the aerial part and the root system. Therefore, greater metabolic responses were noted in plants that were subjected to stress treatment at time 2 (6 days).


Asunto(s)
Vigna , Agua , Deshidratación , Osmorregulación/fisiología , Betaína/análisis
10.
Braz J Biol ; 83: e274643, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37851773

RESUMEN

Sewage sludge (SS) has nutritional contents and has been implemented in the cultivation of seedlings. This study aimed to evaluate the quality of Malpighia emarginata DC. seedlings produced in different substrates with SS. Treatments were implemented with the addition of SS, and after 180 days seedling the characteristics were measured: aerial part and root system length, stem base diameter, number of leaves, fresh and dry mass of aerial part and root, and total biomass. The Dickson Quality Index (DQI) was calculated and the macro and micronutrient content of the aerial part and root. The accumulation of macronutrients in the root system followed the order of N>K>P>Ca>Mg>S, and aerial part of N>Ca>K>P>Mg>S, in the two vegetative structures N and S were in lower concentration. For micronutrients, the accumulation in the root system occurred with Fe>Zn>Mn>Cu>B, and aerial part with Fe>Mn>Zn>B>Cu. It was noted that in the two vegetative structures the Fe content was more concentrated. The use of SS in the substrate formulation proved effective in obtaining viable seedlings for field planting, being recommended the treatment with 60% SS + 40% organic compost.


Asunto(s)
Compostaje , Metales Pesados , Plantones , Aguas del Alcantarillado , Hojas de la Planta/química , Suelo , Metales Pesados/análisis
11.
J Dent Res ; 102(13): 1395-1416, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37967405

RESUMEN

The interest of the scientific community on sex and gender differences in health and disease has increased substantially over the past 25 to 30 y as a result of a long process of events and policies in the biomedical field. This is crucial as compelling evidence from human and animal model studies has demonstrated that sex and gender influence health, molecular and cellular processes, and response and predisposition to disease. The present scoping review aims to provide a synthesis of sex differences in oral diseases, ranging from periodontal disease to orofacial pain conditions, from risk of caries development to apical periodontitis. Overall, findings from this review further support a role for sexual dimorphism influencing disease predisposition and/or progression in oral diseases. Of note, this review also highlights the lack of consideration of additional factors such as gender and other psychosocial and external factors potentially influencing oral health and disease. New conceptual frameworks capable of capturing multiple fundamental domains and measurements should be developed in clinical and preclinical studies to inform sex-based individualized preventive and treatment strategies.


Asunto(s)
Caries Dental , Enfermedades Periodontales , Animales , Humanos , Masculino , Femenino , Enfermedades Periodontales/prevención & control , Salud Bucal , Caries Dental/prevención & control , Susceptibilidad a Enfermedades , Caracteres Sexuales
12.
Braz J Med Biol Res ; 56: e12824, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37585918

RESUMEN

The "timed inspiratory effort" (TIE) index, a new predictor of weaning outcome, normalizes the maximal inspiratory pressure with the time required to reach this value up to 60 s, incorporating the time domain into the assessment of inspiratory muscle function. The objective of this study was to determine whether the TIE predicts successful extubation at a similar rate as the T-piece trial with less time required. A non-inferiority randomized controlled trial was performed with ICU subjects eligible for weaning. The participants were allocated to the TIE or the T-piece groups. The primary outcome was successful weaning, and the main secondary outcome was ICU mortality. Eighty participants of each group were included in the final analysis. Time from the start of a successful test to effective extubation was significantly lower in the TIE group than in the T-piece group, 15 (10 to 24) vs 55 (40 to 75) min, P<0.001. In the Kaplan-Meier analysis, no significant differences were found in successful weaning (79.5 vs 82.5%, P=0.268) or survival rate (62.9 vs 53.8%, P=0.210) between the TIE and T-piece groups at the 30th day. In this preliminary study, the TIE index was not inferior to the T-piece trial as a decision-making tool for extubation and allowed a reduction in the decision time.


Asunto(s)
Extubación Traqueal , Desconexión del Ventilador , Humanos , Respiración Artificial , Factores de Tiempo
13.
Braz J Biol ; 83: e270354, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37820205

RESUMEN

The safflower crop is considered a great alternative for crop rotation since drought tolerance and low production cost are attractive for its choice. However, safflower seeds show dormancy soon after dispersal from the mother plant, making it difficult to successfully establish plants using newly harvested seeds. The influence of temperature, gibberellin and light/dark on dormancy break of safflower seeds during storage were investigated. In a completely randomized design, freshly harvested seeds or stored for 100 and 200 days (paper bag, 20 °C/ 60% UR) were treated with GA3 (0 and 100 µM), at 4, 10 and 25 °C, in the presence and absence of light, during the germination test. Seeds were evaluated for germination percentage, germination speed and seedling survival after 21 days. The temperature of 10 °C, in combination with GA3 (0/100 µM), or light/dark, provided the highest seed germination results, for freshly-harvested seeds and stored seeds. Collectively, these observations indicate that dormancy was not affected by gibberellic acid (100 µM GA3) and the germination results at 21 days were significantly higher, in relation to the use of GA3, under light or dark. Recently harvested seeds could efficiently germinate at 10 °C in the dark, while seeds dry-stored at 20 °C had decreased germination percentages.


Asunto(s)
Carthamus tinctorius , Germinación , Germinación/fisiología , Frío , Temperatura , Plantas , Semillas/fisiología
14.
Braz J Biol ; 83: e276264, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37937632

RESUMEN

The water deficit in particular, reduces the productivity of vegetable crops. To minimize these harmful effects on agriculture, several agronomic and physiological practices are being studied, such as the use of bacteria and water stress attenuators, such as brassinosteroids. Considering the socioeconomic relevance of corn culture and its sensitivity when exposed to water deficit, the objective of the present study was to evaluate the action of brassinosteroids and azospirillum on nitrogen metabolism in corn plants subjected to water stress conditions. The experiment was carried out in a greenhouse, in a period of 47 days, with corn plants, using the hybrid K9606 VIP3. The design was completely randomized, in a 2x2x3 factorial scheme, with six replications. The first factor corresponds to two water regimes (presence and absence of water deficit). The second corresponds to inoculation via seed of Azospirillum brasiliense and absence of inoculation. And the third corresponds to the application of three concentrations of brassinosteroids (0, 0.3 and 0.6 µM). Were determined Nitrate; nitrate reductase; free ammonium; total soluble aminoacids; soluble proteins; proline; glycine betaine and glutamine synthetase. The lack of water in plants provided a reduction in the protein and nitrate reductase contents, in leaves and roots. For ammonium, plants with water deficit inoculated at a concentration of 0.3 µM, obtained an increase of 7.16 (70.26%) and 13.89 (77.04%) mmol NH4 + .Kg-1. DM (Dry mass) on the leaf and root respectively. The water deficit in the soil provided significant increases in the concentrations of glycine betaine, nitrate, proline and aminoacids, both in the leaves and in the roots of the corn plants. On the other hand, the contents of glutamine synthetase had a reduction in both leaves and roots.


Asunto(s)
Compuestos de Amonio , Azospirillum brasilense , Zea mays , Brasinoesteroides/metabolismo , Nitratos , Raíces de Plantas/metabolismo , Sequías , Deshidratación/metabolismo , Betaína/metabolismo , Glutamato-Amoníaco Ligasa , Aminoácidos/metabolismo , Prolina/metabolismo , Nitrato Reductasas/metabolismo , Nitrógeno/metabolismo
15.
Braz J Biol ; 83: e273777, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37970900

RESUMEN

The cowpea bean [Vigna unguiculata (L.) Walp.], a legume of great socioeconomic importance, it was previously cultivated exclusively for subsistence and commercial purposes, especially in the North and Northeast regions. This crop has a low production cost and high nutritional value, in addition to a high potential for productivity growth and expansion to other regions. The objective of this work was to evaluate parameters of growth and production in cowpea culture, as a function of potassium fertilization in soil of the cerrado of Amapá. The parameters of growth and production of the cowpea culture were evaluated, as a function of potassium fertilization in the soil of the cerrado of Amapá. The experiment was conducted in a greenhouse, using a completely randomized experimental design, with four replications, in a 5x2 factorial scheme, totaling 40 experimental units, which were composed of plastic pots containing 7 dm3 of soil collected from the arable layer (0-20 cm ) of a typical Hyperdystrophic Yellow Argisol, with a sandy clay loam texture, in a cerrado area in the municipality of Porto Grande-AP. The factors consisted of the control treatment (without K), four doses of K (45, 90, 135 and 180 kg ha-1) in the form of potassium chloride, and two cowpea cultivars (Pretinho and BRS Tumucumaque). The cultivar BRS Tumucumaque shows better growth and production of cowpea plants. Doses of 90 kg ha-1 provided greater height (98.75 cm) and stem diameter (10.0 mm). As for production, the dose of 135 kg ha-1 caused greater grain weight gain (5.25 g) and dry mass of pods (13.92 g), and the doses of 90 and 180 kg ha-1 induced greater number and length of pods (3.16 pods) respectively. These results show better responsiveness of the BRS Tumucumaque cultivar at doses of 90, 135 and 180 kg ha-1 in the type of soil where the study was conducted.


Asunto(s)
Fabaceae , Vigna , Suelo , Potasio , Brasil
16.
Braz J Biol ; 83: e265991, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37255196

RESUMEN

Water stress limits the initial growth and development of maize mass and grain, as well as the physiological process for absorbing the amount of mineral elements. The objective was to evaluate the effect of silicon on germination and growth of corn seedlings submitted to water deficit. The experiment was carried out in the laboratory and the experimental design was completely randomized (factorial 3 × 4), with three concentrations of calcium silicate (0.0; 1.0 and 2.0 mM) and 4 solutions of PEG-6000 to simulate different osmotic potentials (0, 0; -0.3; -0.6; -0.9 MPa). Germination percentage, germination speed index (GSI), mean germination time (MGT), percentage of non-germinated and abnormal germinated, length and dry matter of shoot, root and total seedlings were evaluated. Water deficiency reduced the parameters TG, GSI and MGT. The water deficit reduce the MSPA, MSR and MST with more than 80% reduction in mass from seedlings without deficiency to seedlings with deficiency. For CPA, CR and CT there was a reduction of at least 87%, 70% and 77%, respectively, among seeds without deficiency compared to seeds submitted to deficiency. The use of silicon in corn seeds did not attenuate the stress caused by water deficit simulated by PEG-6000.


Asunto(s)
Germinación , Plantones , Zea mays , Silicio/farmacología , Semillas
17.
Rev Neurol (Paris) ; 168(11): 815-24, 2012 Nov.
Artículo en Francés | MEDLINE | ID: mdl-22944619

RESUMEN

The diagnosis of Alzheimer's disease has long been considered a diagnosis of probability, as the definitive diagnosis can only be established by histopathological examination. However, the development of in-vivo biomarkers, considered a reflection of physiopathological processes, has changed our view of the disease. New criteria have recently been proposed that integrate such biomarkers as found in the cerebrospinal fluid (CSF) using new diagnostic tools such as magnetic resonance imaging (MRI), brain scintigraphy, FDG-positron emission tomography (PET) and PET amyloid ligand uptake studies. The value of these new criteria for the diagnosis of prodromal Alzheimer's disease and the prospect of disease-modifying drugs are also discussed.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Biomarcadores/análisis , Síntomas Prodrómicos , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/análisis , Péptidos beta-Amiloides/líquido cefalorraquídeo , Encéfalo/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Diagnóstico Precoz , Humanos , Modelos Biológicos , Radiografía , Cintigrafía , Proteínas tau/análisis , Proteínas tau/líquido cefalorraquídeo
18.
Braz J Med Biol Res ; 55: e12331, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36197415

RESUMEN

The aim of this randomized controlled trial was to analyze the effects of an inspiratory muscle training (IMT) program on apnea and hypopnea index (AHI), inspiratory muscle strength, sleep quality, and daytime sleepiness in individuals with obstructive sleep apnea (OSA), whether or not they used continuous positive airway pressure (CPAP (+/-) therapy. The intervention group underwent IMT with a progressive resistive load of 40-70% of the maximum inspiratory pressure (PImax) for 30 breaths once a day for 12 weeks. The control group was submitted to a similar protocol, but with at a minimum load of 10 cmH2O. Changes in the AHI were the primary outcome. PImax was measured with a digital vacuometer, daytime somnolence was measured by the Epworth sleepiness scale (ESS), and the quality of sleep by the Pittsburgh Sleep Quality Index (PSQI). CPAP use was treated as a confounder and controlled by stratification resulting in 4 subgroups: IMT-/CPAP-, IMT-/CPAP+, IMT+/CPAP-, and IMT+/CPAP+. Sixty-five individuals were included in the final analysis. Significant variations were found in the 4 parameters measured throughout the study after the intervention in both CPAP- and CPAP+ participants: PImax was increased and AHI was reduced, whereas improvements were seen in both ESS and PSQI. The twelve-week IMT program increased inspiratory muscle strength, substantially reduced AHI, and had a positive impact on sleep quality and daytime sleepiness, whether or not participants were using CPAP. Our findings reinforce the role of an IMT program as an adjunct resource in OSA treatment.


Asunto(s)
Trastornos de Somnolencia Excesiva , Apnea Obstructiva del Sueño , Presión de las Vías Aéreas Positiva Contínua , Humanos , Músculos , Sueño , Apnea Obstructiva del Sueño/terapia
19.
Oper Dent ; 47(5): 481-491, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36098547

RESUMEN

PURPOSE: This randomized clinical trial aimed to evaluate the postoperative sensitivity of different resin composite/adhesive materials, placed either by an incremental or bulk-fill technique in posterior resin composite replacement of amalgam restorations. METHODS AND MATERIALS: A total of 47 patients with good overall health and at least four class I or class II amalgam restorations to be replaced participated in this study. The characteristics of 188 cavities were registered and randomly restored using incremental (Z350XT, 3M) or bulk-fill (Filtek Bulk Fill, 3M; Sonic Fill, Kerr; and Opus Bulk Fill, FGM) technique. The postoperative sensitivity was assessed using a Visual Analog Scale (0-100) after 24 hours, 7 days, and 30 days. Pain scores were temporally analyzed using Friedman test followed by Dunn post hoc test (α=0.05). The frequency of tests was calculated according to the frequency and percentage of the McNemar test. RESULTS: The restorative technique and the bulk-fill system used did not affect the postoperative sensitivity, except for Filtek Bulk Fill group, which presented less postoperative sensitivity after 24 hours (p=0.037). Regardless of the restorative material, the postoperative sensitivity decreased after 24 hours, and no differences were found after 7 and 30 days. CONCLUSIONS: After 1 week, the filling technique and the bulk-fill system have no influence on the postoperative sensitivity.


Asunto(s)
Caries Dental , Restauración Dental Permanente , Resinas Compuestas/uso terapéutico , Atención Odontológica , Materiales Dentales , Restauración Dental Permanente/métodos , Humanos
20.
Braz J Biol ; 82: e260818, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35857948

RESUMEN

Cowpea (Vigna unguiculata (L.) Walp.) is a legume widely cultivated by small, medium and large producers in several Brazilian regions. However, one of the concerns for the production of cowpea in Brazil in recent years is the low rainfall activity in these regions, which generates the accumulation of salts on the surface. The objective of this work was to evaluate the effects of salt stress on growth parameters and enzyme activity in cowpea plants at different concentrations of brassinosteroids. Experiment was developed in a greenhouse using a completely randomized experimental design in a 3 x 3 factorial scheme. The treatments consisted of three levels of brassinosteroids (0, 3 and 6 µM EBL) and three levels of salt stress (0, 50 and 100 mM NaCl). Growth factors (height, diameter and number of leaves) decreased in the saline condition. With the presence of brassinosteroid the height did not increase, but the number of leaves did, mainly in the saline dosage of 100 mM NaCl. In the variable membrane integrity, brassinosteroid was efficient in both salinity dosages, the same not happening with the relative water content, where the saline condition did not affect the amount of water in the vegetable, with the application of brassino it remained high, decreasing only at dosage 100 mM NaCl. The nitrate reductase enzyme was greatly affected in the root system even with the application of increasing doses of brassino. Therefore, brassinosteroids as a promoter of saline tolerance in cowpea seedlings was positive. The concentration of 3µM of EBL provided the most satisfactory effect in tolerating the deleterious effects of the saline condition. The same cannot be concluded for the concentration of 6µM of EBL that did not promote tolerance to some variables.


Asunto(s)
Fabaceae , Vigna , Brasinoesteroides/metabolismo , Brasinoesteroides/farmacología , Estrés Salino , Cloruro de Sodio/metabolismo , Cloruro de Sodio/farmacología , Vigna/metabolismo , Agua/metabolismo
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