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1.
Variations in genes involved in DNA repair systems have been proposed as risk factors for the development of preeclampsia (PE). We conducted a case-control study to investigate the association of Human apurinic/apyrimidinic (AP) endonuclease (APEX1) Asp148Glu (rs1130409), Xeroderma Pigmentosum group D (XPD) Lys751Gln (rs13181), X-ray repair cross-complementing group 1 (XRCC) Arg399Gln (rs25487) and X-ray repair cross-complementing group 3 (XRCC3) Thr241Met (rs861539) polymorphisms with PE in a Mexican population. Samples of 202 cases and 350 controls were genotyped using RTPCR. Association analyses based on a χ2 test and binary logistic regression were performed to determine the odds ratio (OR) and a 95% confidence interval (95% CI) for each polymorphism. The allelic frequencies of APEX1 Asp148Glu polymorphism showed statistical significant differences between preeclamptic and normal women (p = 0.036). Although neither of the polymorphisms proved to be a risk factor for the disease, the APEX1 Asp148Glu polymorphism showed a tendency of association (OR: 1.74, 95% CI = 0.96–3.14) and a significant trend (p for trend = 0.048). A subgroup analyses revealed differences in the allelic frequencies of APEX1 Asp148Glu polymorphism between women with mild preeclampsia and severe preeclampsia (p = 0.035). In conclusion, our results reveal no association between XPD Lys751Gln, XRCC Arg399Gln and XRCC3 Thr241Met polymorphisms and the risk of PE in a Mexican mestizo population; however, the results in the APEX1 Asp148Glu polymorphism suggest the need for future studies using a larger sample size.  相似文献   

2.
This study observed the effect of a dietary re-education plus regular physical activity on body composition, risk factors and physical test performance of sedentary overweight/obese women and to correlate these variables one with each other. Fifty women (36 ± 10 yrs; 31 ± 6 body mass index (BMI, kg/m2)) volunteered for the study. Body compositions were obtained by anthropometry and bioimpedance and some body indexes were established. One-repetition maximum (1-RM) and treadmill VO2max tests were carried out and blood samples were obtained for lipid, glucose and uric acid analyses before (T1) and after two months of intervention (T2). Diet was established by indirect calorimetry. Body fat, glucose, uric acid, total cholesterol, HDL-cholesterol and systolic blood pressure were significantly reduced. The 1-RM and VO2max tests were significantly increased. Neck circumference (NC) was correlated with body composition, back muscle 1-MR, HDL and LDL cholesterol, total cholesterol/HDL ratio, uric acid, and resting energy expenditure. BMI was found to be significantly correlated with waist/hip ratio, circumference sum, and body fat percentage by anthropometry and bioimpedance. Body fat percentage determined by bioimpedance and anthropometry was significantly correlated with arm fat area and arm fat area corrected respectively, and both with BMI at T1 and T2. This study suggests that a dietary reeducation plus physical activity around 200 min/week improved body composition and the health of these women. Many anthropometry measurements have correspondence to risk factors and NC could be a simple approach to reflect these results, without other more complex techniques.  相似文献   

3.
Fish oil is available primarily as triacylglycerols (TAG) or ethyl esters (EE). Anecdotal evidence suggests that TAG have superior bioavailability and oxidative stability compared to EE. In this work, peroxide value (PV) and p‐anisidine value (AV) were used to monitor oxidation in commercially available TAG and EE fish oils incubated at temperatures from 5 to 60 °C. Pseudo first‐order kinetics were assumed and rate constants were calculated for each temperature. At all temperatures, the rates of oxidation were higher for EE oils than TAG oils. For PV and AV measured in both oils, non‐linear Arrhenius models were plotted, generating activation energies that ranged from 7 to 103 and 2 to 159 kJ/mol for PV and AV, respectively. Although TAG were more resistant to oxidation than EE, they had lower activation energies (Ea) at ≤15 °C for reactions measured with PV and AV. The Ea for EE was negative at temperatures ≥45 °C, indicating that reaction rate was influenced by factors in addition to temperature.  相似文献   

4.
Paraoxonase 1 (PON 1) is an esterase with antioxidant properties that is present in HDL. Gln192Arg polymorphism (also named Q192R or Q/R) of the PON 1 gene that encodes this protein defines two alleles (Q and R). The R allele has been associated with higher cardiovascular risk. LDL size and susceptibility to oxidation also have been identified as cardiovascular risk factors. Our objective was to determine whether genetic variations in the Gln192Arg polymorphism influence LDL size and susceptibility to oxidation after the consumption of diets with different fat content. In our experiments, the participants (n=98), underwent three 4-wk diets—one, saturated fat-enriched (SAT); another, monounsaturated fat-enriched (MONO); and a third, carbohydrate-enriched (CHO). We observed that LDL were smaller in the QQ group after the CHO diet vs. the SAT (P<0.01) and MONO diets (P<0.03). No differences in LDL size were found in QR/RR subjects. When we analyzed lag time of oxidation of LDL, we found that when carriers of the R allele (QR/RR) received the MONO diet, the lag period of LDL oxidation was longer as compared with the CHO diet. Otherwise, we found no differences in QQ homozygotes when we evaluated the lag time of oxidation of LDL after the three diets. These results suggest that the Gln192Arg polymorphism of the paraoxonase gene influences LDL size and susceptibility to oxidation in response to diet.  相似文献   

5.
Leptin is known as the adipose peptide hormone. It plays an important role in the regulation of body fat and inhibits food intake by its action. Moreover, it is believed that leptin level deductions might be the cause of obesity and may play an important role in the development of Type 2 Diabetes Mellitus (T2DM), as well as in cardiovascular diseases (CVD). The Leptin Receptor (LEPR) gene and its polymorphisms have not been extensively studied in relation to the T2DM and its complications in various populations. In this study, we have determined the association of Gln223Agr loci of LEPR gene in three ethnic groups of Malaysia, namely: Malays, Chinese and Indians. A total of 284 T2DM subjects and 281 healthy individuals were recruited based on International Diabetes Federation (IDF) criteria. Genomic DNA was extracted from the buccal specimens of the subjects. The commercial polymerase chain reaction (PCR) method was carried out by proper restriction enzyme MSP I to both amplify and digest the Gln223Agr polymorphism. The p-value among the three studied races was 0.057, 0.011 and 0.095, respectively. The values such as age, WHR, FPG, HbA1C, LDL, HDL, Chol and Family History were significantly different among the subjects with Gln223Agr polymorphism of LEPR (p < 0.05).  相似文献   

6.
The aims of this study were to describe a female obese population according to their food intake and physical activity, and to compare two methods to estimate physical activity (PA). The study included a nutritional interview where a detailed dietary history was done, an initial clinical day in which measurements of body composition and basal metabolic rate (BMR) were carried out and an estimation of PA by means of a triaxial accelerometer and a PA questionnaire. The group of volunteers showed a mean BMI of 37.15 kg/m2, a waist/hip ratio of 0.82 and a mean body fat mass of 43.34%. The average of BMR was 1720 Kcal/d and the CRNP of 0.79. The total caloric intake was 3344 Kcal/d with a energy-distribution of 43.1% Carbohydrates, 16.4% Proteins, 40.3% Lipids. Weight and BMI showed a positive correlation (p < 0.05) with the sedentary index (SI). Also, weight presented a positive correlation with the heart rate (p < 0.05). The estimates of PA derived from the questionnaire showed a positive correlation with the triaxial accelerometer (p < 0.01); and this one, revealed a negative correlation with the SI (p < 0.01). Anthropometric, metabolic and food intake variables are comparable to the results found in obese women from similar socioeconomic background. The estimates of PA according to the questionnaire were significantly correlated to the results of the triaxial accelerometer, thus confirming the validity of the questionnaire to assess PA in an obese population.  相似文献   

7.
The oxidation of model soot by NO2 and O2 in the presence of a Ru/Na‐Y catalyst under conditions close to automotive exhaust gas after‐treatment systems is investigated. Isothermal oxidation experiments of a physical mixture of carbon black and catalyst were performed in a temperature range of 300–400 °C. A remarkable increase of the oxidation rate by NO2 and O2 in the presence of the Ru/Na‐Y catalyst was observed. An overall mechanism involving oxygen transfer from the Ru catalyst to the carbon surface leading to an increase of C(O) complexes is proposed. These C(O) complexes are destabilized in the presence of NO2 increasing the carbon oxidation rate.  相似文献   

8.
《Ceramics International》2017,43(10):7627-7635
The α/β-Bi2O3 photocatalyst was successfully synthesized by a novel solvothermal-calcination method. The physical and chemical properties of as-prepared samples were characterized based on XRD, XPS, SEM, TEM, EDS, BET, UV–vis DRS and PL techniques. The synthesized α/β-Bi2O3 photocatalyst exhibited enhanced photocatalytic activity for 17α-ethinylestradiol (EE2), and 96.9% of EE2 was degraded after only 24 min of visible-light irradiation using α/β-Bi2O3 as photocatalyst. The reaction rate constant over α/β-Bi2O3 photocatalyst was 1.42, 2.23, 9.22 and 54.1 times higher than pure β-Bi2O3, α-Bi2O3+β-Bi2O3, α-Bi2O3 and P25 respectively. Effect of catalyst dosage and pH value was investigated. The possible photocatalytic mechanism has been discussed on the basis of the theoretical calculation and the experimental results. α/β-Bi2O3 was a fairly stable and efficient photocatalyst under the studied experimental conditions, proving that the α/β-Bi2O3 photocatalyst was a promising photocatalyst for the practical application.  相似文献   

9.
Experiments were conducted to study the underwater explosion performance of emulsion explosives (EE) after hot water bath. Spherical charges of EE with different sensitizers and hot water bath were prepared and tested. As for as‐prepared charges, the detonation velocity experiments and underwater explosion experiments were carried out and the crystallization ratio was measured and calculated by the dissolution and neutralization method. The results showed an inverse relationship between explosion parameters (pressure peak, specific impulse, detonation velocity and specific total energy) and heating time. It also revealed that the effective explosive weight of EE was reduced with long time of hot water bath. Moreover, the crystallization ratio and the decreasing rate of explosion parameters of EE sensitized by NaNO2 were apparently higher than EE containing physical sensitizers (glass microballoon and perlite), which was attributed to the different destruction mechanism of EE. After 6‐hour hot water bath, the EE containing physical sensitizers still retained detonator sensitivity and more than 80 % of specific total energy. Meanwhile, the crystallization ratio was less than 20 %. Whereas, the EE sensitized by NaNO2 lost the detonator sensitivity and the crystallization ratio of EE was also above 40 %.  相似文献   

10.
The chemical composition and selected physical parameters of wax extracted from flax straw with supercritical CO2 (SC‐CO2) and hexane have been determined. From the GC/MS results, clear variations in composition and component distributions were observed between SC‐CO2‐ and hexane‐extracted samples. The major components of the SC‐CO2 and hexane extracts from three flax cultivars were: fatty acids (36–49%), fatty alcohols (20–26%), aldehydes (10–14%), wax esters (5–12%), sterols (7–9%) and alkanes (4–5%). Purification of SC‐CO2‐extracted wax with silica gel chromatography yielded 0.4–0.5% (dry matter) and was composed primarily of wax esters (C44, C46 and C48) and alkanes (C27, C29 and C31). UV‐Vis scans of the purified wax samples exhibited two main peaks indicating the presence of conjugated dienes and carotenoids or related compounds. Fourier transform infrared results showed prominent peaks at 2918 (‐C‐H), 2849 (‐C‐H), 1745 (‐C=O), 1462 (‐C‐H), 1169 (‐C‐O) and 719 cm–1 (‐(CH2)n‐), with NorLin wax showing a slightly deviating pattern compared to the other samples. Thermal analysis by differential scanning calorimetry revealed a mean melting point of 55–56 °C and oxidation temperatures of 146–153 °C for purified wax from flax straw processed using different procedures.  相似文献   

11.
The objective of this study was to compare the anthropometry, body composition and biochemical profile between eutrophic and obese children, as well as to relate the children's nutritional state and body composition to those of their respective parents. A control-case study was carried out with 50 eutrophic and 50 obese children paired according to gender, age, socioeconomic condition, and selected from the nutritional evaluation of 2 074 children aged 6 to 8 years, attending public and private urban schools in Vi?osa, Minas Gerais, Brazil. The measurements evaluated were weight, height, circumferences (waist and hip) and thickness skinfolds (triceps and subscapular). The serum levels of glucose, total-cholesterol, HDL, LDL, triglycerides and hemoglobin in the children were evaluated. The obese children presented a larger body size and higher percentage for total body fat as well as its accumulation in the central region, and higher serum levels for triglycerides (p < 0.05). For all biochemical parameters, except for hemoglobin and HDL, there occurred a positive correlation with the located fat in the central region as well as with the total body fat in children (p < 0.05). The obese mothers showing high percentage of body fat and its accumulation in the central region rather tend to have children with these characteristics (p < 0.05). The highest number of the close relatives who are obese and present dyslipidemia is highlighted in the obese children (p < 0.05). This study evidences the differences concerning to the distribution of the body fat and lipid profile among eutrophic and obese children, as well as the strong influence of the maternal obesity upon child's obesity.  相似文献   

12.
A copolymer of 1,6‐hexanediol diacrylate (HDODA) and styrene was prepared by a suspension polymerization method. The resin was characterized by infrared and carbon‐13 cross‐polarization magic‐angle spin (13C CP‐MAS) spectroscopy. The topology of the resin was examined by scanning electron microscopy (SEM). The polymer swells extensively in common solvents used for peptide synthesis. The resin exhibited chemical stability even in neat trifluoroacetic acid. The applicability of the new resin was demonstrated by synthesis of Val‐Ala‐Val‐Ala‐Ala‐Gly, Gln‐Val‐Gly‐Gln‐Val‐Glu‐Leu‐Gly, and Val‐Gln‐Ala‐Ala‐Ile‐Asp‐Tyr‐Ile‐Asn‐Gly. Comparative synthetic studies showed that the new resin is superior to divinylbenzene (DVB)‐based resin in the case of the synthesis of hydrophobic peptide sequences. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1290–1296, 2003  相似文献   

13.
Four different antioxidant activity assays including 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and oxygen radical absorption capacity (ORAC), and thiobarbituric acid reactive substances were performed on the methanolic and ethyl acetate extracts of Camelina seeds (CS), flaxseeds (FS), Camelina meal low fat (CMLF, 9.9% fat), Camelina meal high fat (CMHF, 24.6% fat), and flaxseed meal (FSM, 2.7% fat). In addition, the fatty acid profile, and phenolic, tocopherol, flavonoid, and glucosinolate contents of CS, FS, CMLF, CMHF, and FSM were studied. The major fatty acid was α‐linolenic acid (C18:3 n‐3) which was 33.2, 29.4, 30.2, 60.1, and 39.3% in CS, CMLF, CMHF, FS, and FSM, respectively. The methanolic extract of CMLF showed the highest values of ABTS, DPPH and FRAP and the highest content of phenolic compounds, flavonoids, and glucosinolates. The methanolic and ethylacetate extracts of CMHF showed the highest values for ORAC and α‐ and γ‐tocopherols. The ethylacetate extracts of seeds and meals of Camelina sativa and flax showed lower values for antioxidant activity, phenolic compounds, and flavonoids than the methanolic extracts. In general, Camelina and FS meals showed higher antioxidant activities, and phenolic and flavonoid contents than their respective seeds. Practical applications: Camelina sativa seeds (CS) and flaxseeds (FS) are rich sources of omega 3 oils. Their by‐products after oil extraction are an attractive source of proteins, lipids, fiber, and natural bioactive compounds such as antioxidants. These by‐products may be used to improve nutritional value and prevent lipid oxidation in feed or food systems.  相似文献   

14.
The effects of dietary Cinnamomum camphora seed kernel oil (CCSKO) containing medium‐chain triacylglycerols on lipid metabolism and mRNA and protein expression of β‐3 adrenergic receptor in adipose tissue were studied in diet‐induced obese rats. High fat food‐induced obese rats were randomly divided into CCSKO group, Lard group, Soybean oil (SOY) group and naturally restoring group (n = 10). Rats fed with low fat food were used as a normal control group. Significant decreases in body mass and abdominal fat mass/body mass after 12 weeks were found in CCSKO group as compared with Lard and SOY groups (p < 0.05). Levels of blood total cholesterol (TC), triglyceride, free fatty acid, fasting insulin and insulin resistance in the CCSKO group were decreased significantly, and noradrenaline level and insulin sensitivity index in the CCSKO group were significantly higher than other groups. Meanwhile liver TC and triglyceride levels in the CCSKO group were also decreased markedly. Expression levels of β3‐adrenergic receptor mRNA and protein were higher in CCSKO group than in Lard and SOY groups. These results suggest that CCSKO may contribute to reduction of the body fat mass, promote lipid metabolism and up‐regulate β3‐adrenergic receptor expression in high fat diet‐induced obese rats.  相似文献   

15.
The physicochemical properties of binary and ternary fat systems made of commercial samples of palm oil (PO) blended with anhydrous milk fat (AMF) and/or rapeseed oil (RO) were studied. Physical properties such as solid fat content by pulsed‐Nuclear Magnetic Resonance (p‐NMR), melting profile by differential scanning calorimetry (DSC), and polymorphism of the blends were investigated. Palm oil was then batch enzymatically interesterified for 27 h, using Lipozyme® TL IM as biocatalyst, and further blended with AMF and/or RO in the same way. The objective of the present work was to evaluate the effect of batch enzymatic interesterification (B‐EIE) of palm oil on physical characteristics of the investigated fat blends. For that purpose, iso‐solid diagrams have been constructed from p‐NMR data. It was shown that B‐EIE of palm oil modifies its melting behaviour, but also its polymorphic stability and miscibility with other fats. Under dynamic conditions, after B‐EIE, the non‐ideal behaviour (eutectic) detected at low temperatures in the ternary PO/AMF/RO system disappears in the corresponding EIE‐PO/AMF/RO. After static crystallization followed by a tempering, the hardness of palm oil is increased after B‐EIE, as well as the hardnesses of the blends containing this fat compared to the native one. Polymorphism stability of the binary and ternary fat systems is also modified after B‐EIE compared to the corresponding native systems.  相似文献   

16.
In this study, a new synthesis method was developed for the production of modified sol‐gel alumina (SG‐M) for the selective oxidation of H2S to elemental sulphur. The catalytic activity of this modified alumina without any active metal incorporation was then compared with the activity of commercial alumina (alumina‐com) for H2S selective oxidation. The N2 adsorption‐desorption isotherm showed that the SG‐M alumina synthesized in this work has a mesoporous structure with well‐defined hysteresis loops. Both alumina materials showed a γ‐Al2O3 crystalline phase with an amorphous structure in their crystal structure. The surface acidity of the alumina materials was determined using pyridine‐adsorbed FTIR analyses, and both alumina showed Lewis acid sites on their surfaces. The catalytic activity tests were performed at 250°C using a feed ratio of O2/H2S:0.5. The complete conversion of H2S over SG‐M was achieved during 400 minutes of reaction time. However, the commercial alumina lost its activity at earlier reaction times. Lewis acid sites and surface hydroxyl groups caused the alumina to be active in H2S selective catalytic oxidation, and the formation of Al‐S bonds, observed when the H2S conversion fell, caused a decrease in the catalytic activity of the alumina materials. A high sulphur yield (≥95%) was obtained over SG‐M, even though there was no active metal incorporation and even in the presence of excess oxygen. Considering the catalytic activities, the new sol‐gel alumina synthesized in this work is superior to commercial alumina. It was concluded that, as a catalyst without any active metal, SG‐M is a promising catalyst in H2S selective oxidation to sulphur.  相似文献   

17.
18.
Nucleotide oligomerization domain‐containing protein 2 (Nod2), an innate immune receptor, recognizes bacterial cell‐wall peptidoglycan (PGN), the minimum ligand of which is muramyl dipeptide (MDP). Enzymatic digestion of PGN appears to be important for Nod2 recognition. PGN is degraded by muramidase or glucosamidase through a process that produces two types of glycan sequence; glycans containing GlcNAcβ(1→4)MurNAc or MurNAcβ(1→4)GlcNAc. In this report, a range of disaccharide or tetrasaccharide fragments of each sequence were chemically synthesized, and their activities in stimulating human Nod2 (hNod2) were investigated. The results reveal that hNod2 recognitions is dependent on the glycan sequence, as demonstrated by comparing the activities of glycans with the same peptide moieties. (MurNAcβ(1→4)GlcNAc)2‐containing structures exhibited stronger activity than those containing (GlcNAcβ(1→4)MurNAc)2. The results suggest that differences in the enzymatic degradation process affect the host's immunomodulation process.  相似文献   

19.
Background and aims: to analyze the gender and age differences in the distribution of the high‐density lipoprotein (HDL) subclasses among the Chinese population, and to clarify the mechanism of these changes. Methods and results: the apoA‐I contents of the plasma HDL subclasses were determined by 2‐DE coupled with immunodetection in 324 men (including 186 normolipidemic subjects) and 186 women (including 114 normolipidemic subjects). The contents of preβ1‐HDL and HDL3 (HDL3c, HDL3b, HDL3a) were significantly lower, whereas the contents of HDL2a and HDL2b were higher for women than for men in the <50 years age group. Moreover, the contents of preβ1‐HDL and HDL3 were higher for female subjects; the HDL2a and HDL2b contents were lower for both female and male subjects in the 50–59, 60–69, and ≥70 years age groups versus the subjects of the same gender in the <50 years age group. When compared to the normolipidemic premenopausal women, preβ1‐HDL, HDL3b, and HDL3a increased while HDL2b decreased significantly in normolipidemic men and postmenopausal women. Conclusions: the contents of the large‐sized HDL particles HDL2b were higher, but the contents of the small‐sized HDL particles (preβ1‐HDL, HDL3b, HDL3a) were lower for women versus men in the <50 years age group. Meanwhile, the gender difference in distribution of the HDL subclass narrowed obviously with advancing age. Moreover, the characteristics of the HDL subclass distribution profile for the normolipidemic postmenopausal women resembled those for the normolipidemic men.  相似文献   

20.
Hypercholesterolemia is associated with subclinical inflammation, characterised by elevated proinflammatory mediators. Lyso‐platelet‐activating factor acetyltransferase (lyso‐PAF AT) and lipoprotein‐associated phospholipase A2 (Lp‐PLA2) are two key metabolic enzymes of platelet‐activating factor (PAF), a potent inflammatory lipid mediator. Little information is available concerning the efficacy of a dietary intervention on the metabolism of PAF. The objective of the study was to evaluate the effect of fortified milk on the activity of these enzymes. Forty‐three adults (mean age 49.8 ± 8.1 years) with body mass index <35 kg/m2, and total cholesterol >200 but <310 mg/dL were randomised to two groups; (i) intervention group received 500 mL/day (two glasses) of a low‐fat milk fortified with phytosterols, linoleic and alpha linolenic acids, vitamin C, vitamin E, vitamin A, vitamin B6, vitamin B12, folic acid, magnesium and selenium (n = 22), and (ii) placebo group received 500 mL/day of a conventional low‐fat milk (n = 21) for 3 months. Outcome measures were the activities of lyso‐PAF AT from leukocytes and serum Lp‐PLA2 determined with established methods. None of the activities changed significantly during the study in the intervention group, lyso‐PAF AT (95% confidence interval: ?1.7, 2.3 nmol/min/mg; p = 0.246), and Lp‐PLA2 (?7.8, 5.8 nmol/min/mL, p = 0.591). No difference was observed between the two groups. In conclusion, daily intake of two glasses of phytosterols, antioxidants, linoleic and linolenic acids via fortified milk for three months had no effect on the activity of either lyso‐PAF AT or Lp‐PLA2. Practical applications: Platelet‐activating factor (PAF) was the first intact phospholipid known to have messenger functions in which the signaling results from the molecule binding to specific receptors on the plasma membrane or other membranes of the cell. It has a number of pro‐inflammatory properties, and affects several critical points of atherogenesis including thrombosis, inflammation, and oxidation. Fortification of milk with nutrients that possess anti‐inflammatory properties and administration to adults with elevated blood cholesterol could provide a means to controlling inflammatory process through the synthesis and degradation of PAF in a population group at risk for cardiovascular morbidity and mortality.  相似文献   

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