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201.
Roseli de Souza Santos da Costa Flavia da Silva Santos Daniela de Barros Mucci Tânia Vignuda de Souza Fátima Lucia de Carvalho Sardinha Célia Regina Moutinho de Miranda Chaves Maria das Graças Tavares do Carmo 《Lipids》2016,51(12):1363-1373
The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants. 相似文献
202.
Metformin Reduces Lipogenesis Markers in Obese Mice Fed a Low-Carbohydrate and High-Fat Diet
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Karla Nayara de Oliveira Santana Deborah Farias Lelis Keila Lopes Mendes Jamille Fernandes Lula Alanna Fernandes Paraíso João Marcus Oliveira Andrade John David Feltenberger Junio Cota Diego Vicente da Costa Alfredo Mauricio Batista de Paula André Luiz Sena Guimarães Sérgio Henrique Sousa Santos 《Lipids》2016,51(12):1375-1384
Lipogenesis is the process by which fatty acids are synthesized. In metabolic syndrome, an insulin resistant state along with high plasma levels of free fatty acids (FFA) and hyperglycemia may contribute to the lipogenic process. The aim of the present study was to investigate the effects of oral administration of metformin on the expression of lipogenic genes and glycemic profile in mice fed with low‐carbohydrate high‐fat diet by evaluating their metabolic profile. SWISS male mice were divided into 4 groups (N = 7) that were fed with standard (ST), standard plus metformin (ST + MET), low‐carbohydrate high‐fat diet (LCHFD) and low‐carbohydrate high‐fat diet plus metformin (LCHFD + MET) (100 mg kg?1 diet) diets respectively. Food intake, body weight and blood parameters, such as glucose tolerance, insulin sensitivity, glucose, HDL‐c, total cholesterol, triglycerides, ASL and ALT levels were assessed. Histological analyses were performed on hematoxylin and eosin‐stained epididymal adipose tissue histological specimens. The expression levels of peroxisome proliferator‐activated receptor (PPARγ), sterol regulatory element‐binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl‐CoA carboxylase (ACC), were assessed by RT‐PCR. This study showed that metformin decreased adipocyte area, body weight and food consumption in obese animals when compared to the standard group. Furthermore, the expression of lipogenic markers in adipose tissue were diminished in obese animals treated with metformin. This data showed that oral administration of metformin improved glucose and lipid metabolic parameters in white adipose tissue by reducing the expression of lipogenesis markers, suggesting an important clinical application of MET in treating obesity‐related diseases in metabolic syndrome. 相似文献
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205.
Tiago F. A. Santos Edwar A. Torres Tahiana F. C. Hermengildo Antonio J. Ramirez 《Welding International》2016,30(5):338-347
Usually, a workpiece is deformed during friction stir welding due to high applied loads. Consequently, fully and consolidated friction stir-welded joints as well as tool life time can be affected promoting unscheduled manufacturing stops, which favour decreasing the welding productivity. Furthermore, the workforce is dislocated to not predicted maintenance steps. This work proposes the development of a special ceramic backing to joining and processing material using FSW technologies. Four ceramic deposits were tested over a steel plate, which allowed selecting those with less porosity and, thus, better strength. This backing allowed us to obtain full penetration welds for duplex stainless steels, to high forces during engagement for high-strength low-alloy steels and to obtain consolidated aluminium–steel dissimilar joints. For the last one, there was not adherence of the soft material in the workpiece. In addition, the ceramic backing allowed us to confine the heat and plasticized metal, as well as develop established welding parameters. 相似文献
206.
Optimization of the application of the Fenton chemistry for the remediation of a contaminated soil with polycyclic aromatic hydrocarbons 总被引:1,自引:0,他引:1
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207.
de Melo Henrique João Miller Isidro Julia Saez Cristina Dos Santos Elisama V. Rodrigo Manuel A. 《Journal of Applied Electrochemistry》2022,52(9):1317-1326
Journal of Applied Electrochemistry - This paper evaluates the remediation of soil spiked with lindane using a combined treatment consisting of electrokinetic soil flushing (EKSF) with air... 相似文献
208.
Gleber Tacio Teixeira Rosana Ftima Teixeira Lomba Agatha Densy dos Santos Francisco Joo Francisco Cajaíba da Silva Regina Sandra Veiga Nascimento 《应用聚合物科学杂志》2014,131(12)
To prevent the degradation of the borehole and also the disintegration and dispersion of drilled cuttings, different shale stabilizing additives are used in water‐based drilling fluids (WBFs). Glycols, poly(ethylene glycol), glycerols, and polyglycerol derivatives, also called polyols, have been used to inhibit shales containing reactive clays in WBF. These additives are normally used in conjunction with KCl to reduce clay swelling and dispersion of drilled cuttings. Highly branched polymers have become an important field in current polymer science. Such materials typically exhibit compact, globular structures in combination with an exceptionally high number of sites with functional groups. They have unique properties that differ significantly from their linear counterparts, and the hyperbranched polyglycerol (hPG) is an important hyperbranched polymer that can be produced from an environmentally benign monomer, the glycerol carbonate. In this article, the clay inhibitive properties of hPG were evaluated by different test methods including bentonite inhibition test, cuttings recovery, and X‐ray diffraction measurements. The results show that the hPG has a great potential to be used as an environmental friendly inhibitor additive in WBFs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40384. 相似文献
209.
Rachel Passos de Oliveira Santos Daniele Oliveira Castro Adhemar Coll Ruvolo‐Filho Elisabete Frollini 《应用聚合物科学杂志》2014,131(12)
This investigation focuses on the preparation of bio‐based composites from recycled poly (ethylene terephthalate) (PET) and sisal fibers (3 cm, 15 wt %), via thermopressing process. Plasticizers derived from renewable raw materials are used, namely, glycerol, tributyl citrate (TBC) and castor oil (CO), to decrease the melting point of the recycled PET (Tm ∼ 265°C), which is sufficiently high to initiate the thermal decomposition of the lignocellulosic fiber. All used materials are characterized by thermogravimetric analysis and differential scanning calorimetry, and the composites are also characterized via dynamic mechanical thermal analysis. The storage modulus (30°C) and the tan δ peak values of CT [PET/sisal/TBC] indicate that TBC also acts as a compatibilizing agent at the interface fiber/PET, as well as a plasticizer. To compare different processing methods, rheometry/thermopressing and compression molding are used to prepare the recycled PET/sisal/glycerol/CO composites. These two different methods of processing show no significant influence on the thermal properties of these composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40386. 相似文献
210.
Ariana C. F. Santos Luís P. G. Monteiro Adriana C. C. Gomes Ftima Martel Teresa M. Santos Brbara J. M. Leite Ferreira 《International journal of molecular sciences》2022,23(5)
After the serendipitous discovery of cisplatin, a platinum-based drug with chemotherapeutic effects, an incredible amount of research in the area of coordination chemistry has been produced. Other transition metal compounds were studied, and several new relevant metallodrugs have been synthetized in the past few years. This review is focused on coordination compounds with first-row transition metals, namely, copper, cobalt, nickel or manganese, or with zinc, which have potential or effective pharmacological properties. It is known that metal complexes, once bound to organic drugs, can enhance the drugs’ biological activities, such as anticancer, antimicrobial or anti-inflammatory ones. NSAIDs are a class of compounds with anti-inflammatory properties used to treat pain or fever. NSAIDs’ properties can be strongly improved when included in complexes using their compositional N and O donor atoms, which facilitate their coordination to metal ions. This review focuses on the research on this topic and on the promising or effective results that complexes of first-row transition metals and NSAIDs can exhibit. 相似文献