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1.
Sci Total Environ ; 914: 169836, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38185158

ABSTRACT

Changes in land use and land cover influence the transport of nutrients, mainly phosphorus (P), to aquatic ecosystems. P can be available in the water column to primary producers' assimilation or be stored in different forms in limnic sediment. Therefore, this study aims to analyze the impact of land use and land cover on the spatial distribution of phosphorus forms in the sediment of a tropical semi-arid reservoir. We hypothesize that agriculture, exposed soil and the presence of floodable vegetation increase the amount of mobile phosphorus in the sediment and the sediment closer to the dam show a greater amount of mobile phosphorus due to the confluence of the flows. The classification of land use and land cover was carried out through supervised analysis at the level of the reservoir's drainage basin and area of influence. Sediment samples from the reservoir were collected at four different sampling points within the influence of two sub-basins. P forms were obtained through chemical fractionation of these sediment samples along the reservoir. Sparse Caatinga was the predominant land cover in the drainage basin and in the influence area, accounting for >50 % of these areas. This land cover represents a risk for nutrient transport to aquatic environments. The sediment samples from Boqueirão reservoir exhibited a high amount of phosphorus, mainly in the mobile forms. These forms were heterogeneously distributed throughout the reservoir. Agriculture activities, exposed soil, and floodable vegetation, influence the distribution and increase of mobile forms of phosphorus in the reservoir sediment. This suggests the need for specific strategies for manage these activities properly. Additionally, the sediment closest to the dam showed a lower amount of mobile phosphorus compared to samples further upstream.

2.
Reprod Sci ; 26(12): 1568-1574, 2019 12.
Article in English | MEDLINE | ID: mdl-30782101

ABSTRACT

Endometriosis is frequently related to infertility and little is known about the mechanisms underlying this association. Some studies point to an endometrial factor involved in this condition, which could compromise embryo implantation. Progesterone plays crucial role in endometrial receptivity by acting through progesterone receptor (PGR) isoforms PR-A and PR-B whose expression is epigenetically regulated by DNA methylation, in a specific promoter region for each isoform. Epigenetic changes in PGR-A and PGR-B may be related to progesterone resistance of endometriosis-related infertility. In order to better understand the mechanisms involved in endometrial receptivity, this case-control study aimed to compare the methylation pattern of PGR-A and PGR-B in eutopic endometrium from infertile women with and without endometriosis during the secretory phase. Endometrial biopsies from 19 patients (10 infertile women with endometriosis and 9 infertile controls) with regular cycles were performed during the secretory phase and were dated according to Noyes' criteria. The percentage of DNA methylation at PGR-A and PGR-B was carried out by high-resolution melting assay. The PGR-A gene showed 0% of DNA methylation (unmethylated) in both control and endometriosis groups. However, PGR-B gene showed a partially methylated pattern in majority of the patients (n = 7), with methylation percentage corresponding to 50%, while in the control group the percentage of methylation was 20% (hypomethylated; P = .04). The increased percentage of methylation at PGR-B may be related to reduced gene expression, which could compromise the endometrial receptivity in patients with endometriosis.


Subject(s)
Endometriosis/metabolism , Endometrium/metabolism , Infertility, Female/metabolism , Receptors, Progesterone/metabolism , Case-Control Studies , DNA Methylation , Endometriosis/genetics , Female , Humans , Infertility, Female/genetics , Prospective Studies , Receptors, Progesterone/genetics
3.
Eng. sanit. ambient ; 23(5): 979-986, set.-out. 2018. tab, graf
Article in Portuguese | LILACS | ID: biblio-975138

ABSTRACT

RESUMO A cinza volante é o principal resíduo industrial do uso de carvão mineral na geração de vapor e energia. No Brasil, são produzidas 1,4 milhão toneladas ao ano. Essas cinzas podem ser convertidas em produtos zeolíticos por tratamento hidrotérmico alcalino. Este trabalho teve como objetivo principal realizar essa conversão hidrotérmica, a fim de obter unicamente fases cristalinas zeolíticas para a adsorção de íon amônio. Realizaram-se diversas sínteses alterando o método utilizado (clássico ou de duas fases), o tempo de reação (24 ou 30 h) e a massa de NaOH. A caracterização dos produtos e da cinza (in natura e calcinada) foi realizada por difratometria de raios X, microscopia eletrônica de varredura e, em alguns casos, análises térmica diferencial e gravimétrica (ATD-TG). Os resultados demonstraram que é possível sintetizar as zeólitas hidroxissodalita e cancrinita a partir da cinza estudada. O produto obtido pelo método de duas etapas foi utilizado na adsorção de íon amônio em solução, sendo, neste processo, o modelo isotérmico de Sips o mais adequado; alcançando um valor de capacidade máxima de adsorção de 2,71 mg.g-1.


ABSTRACT Fly ash is the main industrial waste generated by coal in steam and power plans. In Brazil, 1,4 million tons are produced every year. These ashes can be converted into zeolite products by alkaline hydrothermal treatment. The main objective of this paper was to induce this reaction which produces only zeolitic crystalline phases for ammonium ion absorption. So, some syntheses were done by different hydrothermal method (classical or two stages), work time (24 or 30 h) and many NaOH bulks. The characterization of ash (in natura and calcined) and products was performed by X-ray diffraction method, scanning electron microscopy and, in some cases, differential thermal and thermogravimetric analysis The product by two stages method was used in ammonium ion absorption in solution at Sips Mathematic Model: the highest capacity of 2,71 mg.g-1.

4.
Mater Sci Eng C Mater Biol Appl ; 73: 579-584, 2017 Apr 01.
Article in English | MEDLINE | ID: mdl-28183647

ABSTRACT

In this present work, the surface activity of the enzyme asparaginase was investigated at the air-water interface, presenting surface activity in high ionic strengths. Asparaginase was incorporated in Langmuir monolayers of the phospholipid dipalmitoylphosphatidylcholine (DPPC), forming a mixed film, which was characterized with surface pressure-area isotherms, surface potential-area isotherms, polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS), and Brewster angle microscopy (BAM). The adsorption of the enzyme at the air-water interface condensed the lipid monolayer and increased the film compressibility at high surface pressures. Amide bands in the PM-IRRAS spectra were identified, with the CN and CO dipole moments lying parallel to monolayer plane, revealing the structuring of the enzyme into α-helices and ß-sheets. The floating monolayers were transferred to solid supports as Langmuir-Blodgett (LB) films and characterized with fluorescence spectroscopy and atomic force microscopy. Catalytic activities of the films were measured and compared to the homogenous medium. The enzyme accommodated in the LB films preserved more than 78% of the enzyme activity after 30days, in contrast for the homogeneous medium, which preserved less than 13%. The method presented in this work not only allows for an enhanced catalytic activity, but also can help explain why certain film architectures exhibit better performance.


Subject(s)
1,2-Dipalmitoylphosphatidylcholine/chemistry , Asparaginase/metabolism , Adsorption , Biocatalysis , Enzymes, Immobilized/metabolism , Escherichia coli/enzymology , Microscopy, Atomic Force , Pressure , Spectrometry, Fluorescence , Spectrophotometry, Infrared , Surface Properties , Temperature
5.
Reprod. clim ; 32(2)2017. ilus, tab
Article in Portuguese | LILACS | ID: biblio-883381

ABSTRACT

Objetivos: Alterações moleculares no endométrio eutópico de mulheres com endometriose podem estar envolvidas na infertilidade associada à doença. Este estudo objetivou comparar os genes diferencialmente expressos (DEG) no endométrio eutópico de mulheres inférteis com endometriose, controles inférteis (CI; fator masculino e/ou tubário) e controles férteis (CF) durante a janela de implantação, através de RNA­Seq. Material e métodos: Biópsias endometriais foram obtidas de 17 pacientes (seis inférteis com endometriose, seis CI e cinco CF) durante a janela de implantação. O RNA total foi extraído e o RNA­Seq foi feito na plataforma Illumina HISEQ 2500, high output, paired end. A normalização dos dados e a expressão diferencial foram conduzidas no ambiente estatístico R através do pacote DESeq2. Resultados: Os grupos CI e CF foram semelhantes. Nenhum DEG foi identificado quando comparados os grupos CF e endometriose (independentemente do estágio da doença). Cinco DEGs (SCUBE1, CCL20, LGALS9C, TRIM 29 e WNT11) foram identificados no grupo endometriose avançada (EIII/IV) e um DEG (KANSL1­AS1) no grupo endometriose inicial (EI/II), quando comparados com o CF. Dois DEGs (KANSL1­AS1 e VGLL3) foram identificados com a comparação de EI/II e EIII/IV. Conclusões: Os dados sugerem que o endométrio eutópico de mulheres inférteis com endometriose, especialmente na doença avançada, seja molecularmente diferente do endométrio eutópico de mulheres férteis durante a janela de implantação.(AU)


Molecular alterations in the eutopic endometrium of women with endometriosis may be involved in the endometriosis­related infertility. This study aimed to compare the differentially expressed genes (DEG) in eutopic endometrium of infertile women with endometriosis, infertile controls (IC; male and/or tubal factor) and fertile controls (FC) through RNA­Seq. Material and methods: Endometrial biopsies were obtained from 17 patiens (6 infertile women with endometriosis, 6 IC and 5 FC) during the implantation window. The RNA was extracted and the RNA­Seq was performed at a HISEQ 2500 Illumina Platform, high output, paired end. Standardization and differential expression were conducted in the statistical R environment using DESeq2 package. Results: The groups IC and FC were similar. No DEG has been identified comparing CF and endometriosis groups. Five DEGs (SCUBE1, CCL20, LGALS9C, TRIM 29 e WNT11) were identified in the advanced endometriosis (EIII/IV) group, and 1 (KANSL1­AS1) in the initial endometriosis (EI/II) group compared to FC. Two DEGs (KANSL1­AS1 and VGLL3) were identified by comparing EI/II and EIII/IV groups. Conclusions: These data suggest that the eutopic endometrium of infertile women with endometriosis, especially those with advanced disease, may be molecularly different from those of fertile women during the implantation window.(AU)


Subject(s)
Humans , Female , Adult , Middle Aged , Young Adult , Endometriosis , Endometrium , Infertility, Female , RNA
6.
Rev. colomb. cienc. pecu ; 29(4): 245-254, oct.-dic. 2016. tab, graf
Article in English | LILACS | ID: biblio-959978

ABSTRACT

Summary Background: phosphorus supplementation should help to keep bone integrity and prevent fractures during the development and slaughter of animals. Objective: to evaluate the effect of different phosphorus sources on one characteristics of pigs. Methods: one-hundred and twelve piglets (28.65 ± 2.82 Kg body weight) were distributed into an 8×2 factorial arrangement (eight sources of phosphorus × two sexes) in blocks in a completely randomized design. The diets were formulated on a total-phosphorus basis, with 0.32 and 0.31% of P for the control diet and 0.56 and 0.42% of P for the other treatments in the growth and finishing phases, respectively. Phosphorus was supplemented as dicalcium phosphate (DCP); mono-dicalcium phosphate (MDCP); triple superphosphate (TSP); single superphosphate (SSP); Catalão-rock phosphate (ROCK); a mixture of sources (MIX); phosphoric acid (PPA); and the control diet (CTR). Results: there was no interaction between phosphorus sources and sex in any of the parameters. Thickness of the compact tissue was the lowest in the CTR, differing from the diets containing DCP, MDCP, and PPA, followed by diets SSP, TSP, and ROCK, with the greatest value for MDCP. Porosity of the compact tissue was higher for the CTR and SSP diets. Conclusion: the use of less elaborate sources of phosphorus, such as rock phosphate and single superphosphate, was less effective than the other sources to improve bone integrity of pigs.


Resumen Antecedentes: la suplementación dietaria con fósforo ayuda a mantener la integridad del hueso y prevenir fracturas durante el desarrollo y sacrificio de los animales. Objetivo: evaluar el efecto de diferentes fuentes de fósforo sobre las características óseas de los cerdos. Métodos: ciento doce lechones (peso corporal: 28,65 ± 2,82 Kg) se distribuyeron en un arreglo factorial 8×2 (ocho fuentes de fósforo × dos sexos) en bloques al azar. Las dietas se formularon con base en fósforo total, con 0,32 y 0,31% de P para la dieta control y 0,56 y 0,42% de P para los otros tratamientos en las fases de crecimiento y finalización, respectivamente. El fósforo se suplementó como fosfato dicálcico (DCP), monofosfato dicálcico (MDCP), superfosfato triple (TSP), superfosfato simple (SSP), fosfato de roca Catalão (ROCK), mezcla de fuentes (MIX), ácido fosfórico (PPA) y dieta control (CTR). Resultados: no se observó interacción entre las fuentes de fósforo y el sexo en ninguno de los parámetros estudiados. El espesor del tejido compacto fue más bajo en el CTR, y diferente a las dietas que contenían DCP, MDCP y PPA, seguido por las dietas SSP, TSP y ROCK; con el mayor valor para MDCP. La porosidad del tejido compacto fue mayor para las dietas CTR y SSP. Conclusión: el uso de fuentes menos elaboradas de fósforo, tales como el fosfato de roca y superfosfato simple, fue menos efectivo que las otras fuentes en mejorar la integridad ósea de los cerdos.


Resumo Antecedentes: a suplementação de fósforo deve manter a integridade do tecido ósseo e prevenir fraturas durante o desenvolvimento e abate dos animais. Objetivo: avaliar o efeito de diferentes fontes de fósforo sobre as características ósseas dos suínos. Métodos: cento e doze leitões com peso médio inicial de 28,65 ± 2,82 Kg foram distribuídos em esquema fatorial 8×2 (oito fontes de fósforo × dois sexos) em blocos casualizados. As dietas foram formuladas baseadas em fósforo total com 0,32 e 0,31% de P para a dieta controle e com 0,56 e 0,42% de P para os outros tratamentos nas fases de crescimento e terminação, respectivamente. O fósforo nas dietas foi suplementado com fosfato bicálcico (DCP); mono-fosfato bicálcico (MDCP); superfosfato triplo (TSP); superfosfato simples (SSP); fosfato de rocha Catalão (ROCK); uma mistura de fontes (MIX); ácido fosfórico (PPA); e a dieta controle (CTR). Resultados: não houve interação entre as fontes de fósforo e sexo dos animais para qualquer um dos parâmetros estudados. A espessura do tecido compacto é menor na CTR, diferenciando-se das dietas DCP, MDCP e PPA, seguido pelas dietas SSP, TSP e ROCK, sendo que o maior valor foi observado na dieta com MDCP. A porosidade do tecido compacto foi maior com as dietas CTR e SSP. Conclusão: o uso de fontes menos elaboradas de fósforo como superfosfato simples e fosfato de rocha foram menos eficientes do que os outros tratamentos para melhorar a integridade óssea de suínos.

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