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The demand for bio-based retinol (vitamin A) is currently increasing, however its instability represents a major bottleneck in microbial production. Here, we developed an efficient method to selectively produce retinol in Yarrowia lipolytica. The β-carotene 15,15′-dioxygenase (BCO) cleaves β-carotene into retinal, which is reduced to retinol by retinol dehydrogenase (RDH). Therefore, to produce retinol, we first generated β-carotene-producing strain based on a high-lipid-producer via overexpressing genes including heterologous β-carotene biosynthetic genes, GGS1F43I mutant of endogenous geranylgeranyl pyrophosphate synthase isolated by directed evolution, and FAD1 encoding flavin adenine dinucleotide synthetase, while deleting several genes previously known to be beneficial for carotenoid production. To produce retinol, 11 copies of BCO gene from marine bacterium 66A03 (Mb.Blh) were integrated into the rDNA sites of the β-carotene overproducer. The resulting strain produced more retinol than retinal, suggesting strong endogenous promiscuous RDH activity in Y. lipolytica. The introduction of Mb.Blh led to a considerable reduction in β-carotene level, but less than 5% of the consumed β-carotene could be detected in the form of retinal or retinol, implying severe degradation of the produced retinoids. However, addition of the antioxidant butylated hydroxytoluene (BHT) led to a >20-fold increase in retinol production, suggesting oxidative damage is the main cause of intracellular retinol degradation. Overexpression of GSH2 encoding glutathione synthetase further improved retinol production. Raman imaging revealed co-localization of retinol with lipid droplets, and extraction of retinol using Tween 80 was effective in improving retinol production. By combining BHT treatment and extraction using Tween 80, the final strain CJ2104 produced 4.86 g/L retinol and 0.26 g/L retinal in fed-batch fermentation in a 5-L bioreactor, which is the highest retinol production titer ever reported. This study demonstrates that Y. lipolytica is a suitable host for the industrial production of bio-based retinol.  相似文献   

3.
Provitamin A (proVA) carotenoids are converted into retinol (vitamin A) in the human body, are the subject of human nutrition studies, and are targets for biofortification of staple crops. β-Carotene has been the principal target for enhancing levels of proVA. There is recent interest in enhancing the proVA carotenoid β-cryptoxanthin since it has excellent bioavailability, and in maize may be nearly as effective as β-carotene in providing retinol to humans. This study was designed to enhance our understanding of the genetic control of: levels of β-cryptoxanthin, conversion of β-carotene into β-cryptoxanthin and zeaxanthin, conversion of β-cryptoxanthin into zeaxanthin, and flux into and within the β-branch of carotenoid pathway. A biparental population derived from two inbreds with relatively high levels of β-cryptoxanthin and different ratios of β-carotene to β-cryptoxanthin and β-cryptoxanthin to zeaxanthin was studied. Three field replications of this F2:3 population were grown, grain analyzed by liquid chromatography (LC), and composite interval mapping (CIM) performed to identify 90 quantitative trait loci (QTL) for carotenoids. We detected QTL for β-carotene/(β-cryptoxanthin + zeaxanthin) and (β-carotene + β-cryptoxanthin)/zeaxanthin ratios that contain candidate gene hydroxylase 4 (hyd4), which has not been previously associated with QTL for carotenoids in maize grain. Two color assessment methods, visual score and chromameter reading, were used to phenotype one replicate of the population for initial assessment as simple alternative measuring procedures. A common finding for LC and chromameter analysis included QTL on chromosome 5 that contain candidate gene lycopene β cyclase (lcyβ).  相似文献   

4.
We are presenting the first ultra-high pressure LC (UHPLC) method for rapid quantitative measurement of vitamin A, E (α- and γ-tocopherol), β-carotene and CoQ10 from human serum. The chromatography was performed on Shield RP18 UHPLC column with UV detection. The method was validated based on linearity, accuracy, matrix effects study, precision and stability. The calibration was linear over the following range: 0.09–10.0 for retinol and γ-tocopherol, 0.05–5 for β-carotene, 0.9–100 for α-tocopherol and 0.14–15 mg/L for CoQ10. The limit of detection and quantitation for retinol, γ-tocopherol, β-carotene, α-tocopherol and CoQ10 were as follows 0.07/0.024, 0.018/0.06, 0.004/0.12, 0.078/0.261, 0.008/0.028 mg/L. The recoveries were above 85%. The inter- and intra-assay precision was below 10%. Reference intervals were established for children and adults. Because of its low cost, extremely short analysis time (2 min) and excellent chromatographic reproducibility this UHPLC method can easily be adopted for high-throughput clinical and pharmacokinetics studies.  相似文献   

5.
In order to investigate the antioxidant effect of β-carotene in vivo, phospholipid hydroperoxides and β-carotene isomers in red blood cells (RBC), plasma and tissue organelles were quantitatively measured after the oral administration of β-carotene (94.8% all-trans-β-carotene) to mice. Three groups of 24 mice each were fed for 1 week on a semisynthetic diet supplemented with either 0.6% or 3.0% β-carotene/diet or maintained on a control (β-carotene-unsupplemented) diet. The RBC phospholipid hydroperoxides showed a significant decrease followed by an increase of β-carotene intakes; i.e., 201, 16 and 4 pmol of phosphatidylcholine hydroperoxide/ml packed RBC, and 108, 22 and 8 pmol of phosphatidylethanolamine hydroperoxide/ml packed RBC, in the mice given the control diet, 0.6% carotene diet and 3.0% carotene diet, respectively. The RBC β-carotene increased from 14 to 43 pmol/ml packed RBC as followed by the increase of β-carotene intakes. Such a potent antioxidant effect of β-carotene as observed in RBC was not confirmed in the plasma, liver or lungs, although their β-carotene contents increased. The β-carotene ingestion increased the all-trans-β-carotene d and retinol contents in RBC, plasma, liver and lungs, but the α-tocopherol content decreased. In the β-carotene-supplemented (6 g and 30 g/kg diet) mice, cis-β-carotene content was relatively higher in the RBC (25–35% of total β-carotene) than that in plasma, liver and lungs. The present findings indicate that not only does β-carotene act as a potent antioxidant in vivo but also its antioxidant effect is very specific in the RBC phospholipid bilayers rather than in the plasma and other tissue organelles.  相似文献   

6.
High-carotenoid (HC) maize, a biofortified staple crop which accumulates β-carotene, β-cryptoxanthin, lutein and zeaxanthin, was used as a feed component in a chicken feeding trial to assess the bioavailability of provitamin A (PVA) carotenoids in the kernel matrix compared to the synthetic and natural color additives routinely used in the poultry industry. We found that the PVA carotenoids in HC maize were not metabolized in the same manner: β-carotene was preferentially converted into retinol in the intestine whereas β-cryptoxanthin accumulated in the liver. We also considered the effect of zeaxanthin on the absorption of PVA carotenoids because zeaxanthin is the major carotenoid component of HC maize. We found that chickens fed on diets with low levels of zeaxanthin accumulated higher levels of retinol in the liver, suggesting that zeaxanthin might interfere with the absorption of β-carotene, although this observation was not statistically significant. Our results show that HC maize provides bioavailable carotenoids, including PVA carotenoids, and is suitable for use as a feed component.  相似文献   

7.
  • 1.1. High performance liquid chromatography (HPLC) was used to determine β-carotene and retinol in cow serum.
  • 2.2. Two groups of state and private farm cows (Groups 1 and 2) were used to assess seasonal variation when different food sources were fed to cows on serum β -carotene and retinol concentrations.
  • 3.3. Mean serum concentrations of β-carotene and retinol from October to April in both Groups 1 and 2 cows were lower (P < 0.05) than in the other months when the cows were fed various combination of maize silage, alfalfa and carrot residues and grass hay, respectively.
  • 4.4. Mean serum β-carotene and retinol concentrations in June and July were higher (P < 0.05) than in other months when the cows were in pasture.
  • 5.5. Mean serum β-carotene and retinol concentrations in May, August and September were lower (P < 0.05) than in June and July and higher (P < 0.05) than in other months when a lesser amount of green pasture was available to the cows.
  • 6.6. There was a seasonal variation (P < 0.05) in serum β -carotene and retinol concentrations. When the carotene intake is very high, conversion of β -carotene to retinol decreases. Mean monthly serum β -carotene and retinol concentrations showed that combination of alfalfa hay and maize silage, and grass hay and carrot residues can maintain adequate serum β-carotene and retinol concentrations during the dry season.
  相似文献   

8.
An improved isocratic and rapid HPLC method was developed for the measurement of carotenoids, retinol and tocopherols in human serum. Vitamins were extracted with hexane. Mobile phase consisted of a mixture acetonitrile:methylene chloride:methanol with 20 mM ammonium acetate. This method used a small bead size (3 μm) Spherisorb ODS2 column with titane frits. Diode array and fluorescence detectors were used respectively for the detection of carotenoids and retinol/tocopherols. Chromatographic separation was complete in 13 min for β-cryptoxanthin, cis–trans-lycopene, α-carotene, β-carotene, cis-β-carotene, retinol, δ-tocopherol, γ-tocopherol and α-tocopherol. Echinenone and tocol were employed as internal standards for diode array and fluorescence detection. Accuracy was validated using standard reference material (SRM) 968C. Intra-assay and inter-assay precision were respectively 0.2–7.3% and 3.6–12.6%. Sensitivity was verified using the ICH recommendations and the limit of detection (LOD) obtained was sufficient for routine clinical application.  相似文献   

9.
The formation, stability and in vitro digestion of milk fat globule membrane (MFGM) proteins stabilized emulsions with 0.2 wt% β-carotene were investigated. The average particle size of β-carotene emulsions stabilized with various MFGM proteins levels (1%, 2%, 3%, 4%, 5% wt%) decreased with the increase of MFGM proteins levels. When MFGM proteins concentration in emulsions is above 2%, the average particle size of β-carotene emulsions is below 1.0 μm. A quite stable emulsion was formed at pH 6.0 and 7.0, but particle size increased with decrease in acidity of the β-carotene emulsion. β-carotene emulsions stabilized with MFGM proteins were stable with a certain salt concentrations (0–500 mMNaCl). β-carotene emulsions were quite stable to aggregation of the particles at elevated temperature and time (85 °C for 90 min). At the same time, β-carotene emulsions were stable against degradation under heat treatment conditions. In vitro digestion of β-carotene emulsion showed the mean particle size of β-carotene emulsions stabilized with MFGM proteins in the simulated stomach conditions and intestinal conditions is larger than that of initial emulsions and simulated mouth conditions. Confocal laser scanning microscopy of β-carotene MFGM proteins emulsions also showed the corresponding results to different vitro digestion model. There was a rapid release of free fatty acid (FFA) during the first 10 min and after this period, an almost constant 70% digestion extent was reached. Approximately 80% of β-carotene was released within 2 h of incubation under the simulated intestinal fluid. These results showed that MFGM protein can be used as a good emulsifier in emulsion stabilization, β-carotene rapid release as well as lipophilic bioactive compounds delivery.  相似文献   

10.

Background

Exclusive breastfeeding (EBF) during infancy is fundamental, however it is not fully practiced in the nomadic population of Ethiopia. In Ethiopia, there is still a lack of information on the implementation of the EBF, especially among the nomadic population. This study was conducted to assess the EBF status of children during their first 6 months of life, who are now aged between 6 and 24 months, in the nomadic population of Afar region. The study also aimed to identify factors affecting exclusive breastfeeding.

Methods

A community based cross-sectional study was conducted from April to May, 2015 to assess EBF of children aged between 6 and 24 months during the first 6 months of life. Exclusive breastfeeding is defined as consuming only breast milk (including expressed breast milk) during the first 6 months and no other liquids and solid foods except medications, and non exclusive breastfeeding is taking liquids and solid foods in addition to breast milk. The cluster sampling technique was used to select the study participants. Data were collected from 254 households using a structured questionnaire.

Results

One hundred eighty eight of the children were fed breast milk exclusively for the first 6 months of age; the rate of EBF in the study area was 74% (95% CI 70, 78%). One hundred fifty four (60.6%) of the children received breast milk within 1 h immediately after birth and 207 (81.5%) of the children maintained breastfeeding at the time of the survey. Exclusive breastfeeding was statistically associated with mothers aged above 35 years (AOR 8.3, 95% CI 1.7, 40.3), commencing to breastfeed in first hour (AOR 3.5, 95% CI 1.8, 6.9), and parents who didn’t migrate or move to a more comfortable area (AOR 4.6, 95% CI 1.5, 14.4).

Conclusion

Exclusive breastfeeding was not fully practiced in the study area. Therefore, promotion of infant and young children feeding (IYCF) is needed in the area to strengthen EBF practices. Moreover, child feeding practices should be integrated with the existing health system and attention should be given to the nomadic mothers.
  相似文献   

11.
The intestinal absorption and metabolism of β-carotene is of vital importance in humans, especially in populations that obtain the majority of their vitamin A from provitamin A carotenoids. MS has provided a better understanding of the absorption of β-carotene, the most potent provitamin A carotenoid, through the use of stable isotopes of β-carotene. We report here an HPLC-MS method that eliminates the need for complicated sample preparation and allows us to detect and quantify newly absorbed d8-β-carotene as well as its d4-retinyl ester metabolites in human plasma and chylomicron fractions. Both retinoids and β-carotene were recovered in a single simple extraction that did not involve saponification, thus allowing subsequent quantitation of individual fatty acyl esters of retinol. Separation of d8-β-carotene and its d4-retinyl ester metabolites was achieved using the same C30 reversed-phase liquid chromatography followed by mass spectrometry in selected ion monitoring and negative atmospheric pressure chemical ionization modes, respectively. Total time for the two successive runs was 30 min. This HPLC-MS method allowed us to quantify the absorption of intact d8-β-carotene as well as its extent of conversion to d4-retinyl esters in humans after consumption of a single 5 mg dose of d8-β-carotene.  相似文献   

12.
The trend of pastoral sedentarization in Africa presents new economic opportunities to women through the sale of dairy products, agricultural produce, and labor. This study of Rendille of northern Kenya shows a variety of economic strategies pursued by women in nomadic pastoral, settled agro-pastoral, and town communities. Results of household budgets and interviews with married women indicate that urban centers attract both wealthier Rendille women selling milk and poorer women engaged in wage-labor and petty commodity trade; time allocation data shows that women living in towns work as strenuously as those in pastoral communities, while men in towns work less than in pastoral communities and less than women in both communities; and anthropometric data of women and children suggest that increases in women's income may have a beneficial effect on the nutrition and well-being of their children.  相似文献   

13.
Malnutrition, resulting from various etiologies, is common in rural Chadian women and children. This cross-sectional study assessed the spectrum of parasitic infection and level of anemia and their effect on nutritional status in settled and mobile pastoral mothers and children near Lake Chad. Intestinal parasites were evaluated using direct fecal smears and the Kato-Katz technique. Malaria status was determined using Paracheck-Pf(?) rapid diagnostic test, and anemia was assessed with the Hemocue photometer. Nutritional status was evaluated using anthropometric parameters. At the end of the 2008 wet season, the prevalence of malnutrition was 36% [confidence interval (CI) 30-42] among women and 15% (CI 11-18) among children. The prevalence of intestinal parasitic infection was 75% (CI 68-83) among women and 60% (CI 53-66) among children. The predominant helminth species was Ascaris lumbricoides while Entamoeba histolytica/dispar was the most common protozoan. The hookworm prevalence was 14% (CI 8-20) in women and 18% (CI 13-23) in children. Malaria prevalence was low among women (1%, CI 0.5-2) and children (3% CI 2-5). No significant difference was observed in the prevalence of parasitic infection between the mobile pastoralist and rural sedentary populations. Thirty-four percent (CI 27-40) of nonpregnant women, 53% (CI 34-72) of pregnant women, and 27% (CI 23-32) of children were anemic. In subjects infected with Plasmodium, all women and 54% (CI 22-85) of children were anemic. Malnutrition was significantly associated with anemia in mothers and with selected intestinal parasites, anemia and age in their children.  相似文献   

14.
There is a lack of studies that analyze the association between micronutrient-related biomarker status and physical fitness in adolescents. In the present study, biochemical parameters for iron and vitamin status were studied, along with objective measures of physical fitness in healthy male and female European adolescents. One thousand eighty-nine adolescents (580 girls, 12.5-17.5 yr) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study were included. Hierarchical linear models were performed to determine the associations between micronutrient biomarkers and physical fitness. Age, seasonality, latitude, body mass index, menarche (in girls), and physical activity were used as covariates. For cardiorespiratory fitness, concentrations of hemoglobin, retinol, and vitamin C in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with maximal oxygen consumption. For muscular fitness, concentrations of hemoglobin, β-carotene, retinol, and α-tocopherol in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with better performance of the standing long jump test. In summary, concentrations of hemoglobin and most antioxidant vitamins in male adolescents and β-carotene and 25(OH)D in female adolescents were positively associated with cardiorespiratory and muscular fitness, after controlling for relevant confounders. The associations between physical fitness and iron or vitamin status observed in this cross-sectional study in adolescents should be followed up by a study specifically designed to evaluate causal relationships.  相似文献   

15.

Objective

To determine the factors associated with excessive body fat among black African men and women living in rural and urban communities of South Africa.

Methods

This is a cross-sectional analysis of data from the Prospective Urban and Rural Epidemiology (PURE) study, Cape Town, South Africa conducted in 2009/2010. The study sample included 1220 participants (77.2% women) aged 35–70 years, for whom anthropometric measurements were obtained and risk factors documented through face-to-face interviews using validated international PURE study protocols. Sex-specific logistic regression models were used to evaluate socio-demographic, lifestyle and psychological factors associated with three excessive body fat indicators, namely body mass index (BMI), waist circumference (WC) and body fat percent (BF%).

Results

The prevalence of excessive body fat based on BF%, WC and BMI cut-offs were 96.0%, 86.1%, and 81.6% for women respectively, and 62.2%, 25.9%, and 36.0% for men respectively. The significant odds of excessive body fat among the currently married compared to unmarried were 4.1 (95% CI: 1.3–12.5) for BF% and 1.9 (95% CI: 1.3–2.9) for BMI among women; and 4.9 (95% CI: 2.6–9.6), 3.2 (95% CI: 1.6–6.4) and 3.6 (95% CI: 1.9–6.8) for BF%, WC and BMI respectively among men. Age ≤50 years (compared to age >50 years) was inversely associated with excessive BF% in men and women, and less-than-a-college education was inversely associated with excessive BMI and WC in men. Tobacco smoking was inversely associated with all three excessive adiposity indicators in women but not in men. Unemployment, depression, and stress did not predict excessive body fat in men or women.

Conclusion

The sex-differences in the socio-demographic and lifestyle factors associated with the high levels of excessive body fat in urban and rural women and men should be considered in packaging interventions to reduce obesity in these communities.  相似文献   

16.

Introduction

The disease burden and risk factors for respiratory syncytial virus (RSV) and human metapneumovirus (MPV) infections among children living in remote, rural areas remain unclear.

Materials and Methods

We conducted a prospective, household-based cohort study of children aged <3 years living in remote rural highland communities in San Marcos, Cajamarca, Peru. Acute respiratory illnesses (ARI), including lower respiratory tract infection (LRTI), were monitored through weekly household visits from March 2009 through September 2011. Nasal swabs collected during ARI/LRTI were tested for RSV, MPV, and other respiratory viruses using real-time RT-PCR. Incidence rates and rate ratios were calculated using mixed effects Poisson regression.

Results

Among 892 enrolled children, incidence rates of RSV and MPV ARI were 30 and 17 episodes per 100 child-years, respectively. The proportions of RSV and MPV ARI that presented as LRTI were 12.5% and 8.9%, respectively. Clinic visits for ARI and hospitalizations were significantly more frequent (all p values <0.05) among children with RSV (clinic 41% and hospital 5.3%) and MPV ARI (38% and 3.5%) when compared with other viral infections (23% and 0.7%) and infections without virus detected (24% and 0.6%). In multivariable analysis, risk factors for RSV detection included younger age (RR 1.02, 95% CI: 1.00-1.03), the presence of a smoker in the house (RR 1.63, 95% CI: 1.12-2.38), residing at higher altitudes (RR 1.93, 95% CI: 1.25-3.00 for 2nd compared to 1st quartile residents; RR 1.98, 95% CI: 1.26-3.13 for 3rd compared to 1st quartile residents). Having an unemployed household head was significantly associated with MPV risk (RR 2.11, 95% CI: 1.12-4.01).

Conclusion

In rural high altitude communities in Peru, childhood ARI due to RSV or MPV were common and associated with higher morbidity than ARI due to other viruses or with no viral detections. The risk factors identified in this study may be considered for interventional studies to control infections by these viruses among young children from developing countries.  相似文献   

17.
Attempts were made to evaluate 709 children (324 boys and 385 girls) who had been exposed long-term to different doses of radiation during and after the Chernobyl accident and had moved to Israel between 1990 and 1994. Upon arrival, all of them underwent a check-up for most common clinical disorders and were then divided into three groups according to their residences (distance from the reactor) and the level of irradiation exposure: no radiation, <5 Ci/m2, and >5 Ci/m2, respectively. Blood serum analyses for total carotenoids, retinol, α-tocopherol and oxidized conjugated dienes in 262 of the children showed increased HPLC levels of conjugated dienes, indicating increased levels of oxidation of in vivo blood lipids in children from the contaminated areas. The levels were higher in girls than in boys. Some 57 boys and 42 girls were given a basal diet with a diurnal supplementation of 40 mg natural 9-cis and all-trans equal isomer mixture β-carotene in a capsulated powder form of the alga Dunaliella bardawil, for a period of 3 months. Blood serum analyses were regularly conducted before supplementation to determine the baseline effect of radiation exposure to the children, after 1 and 3 months of natural β-carotene supplementation. After supplementation, the levels of the oxidized conjugated dienes decreased in the children's sera without any significant changes in the level of total carotenoids, retinol or α-tocopherol. Other common blood biochemicals were within the normal range for all tests and no statistical differences before or after supplementation of β-carotene were noted. High pressure liquid chromatography (HPLC) analyses for carotenoids in the blood detected mainly oxycarotenoids, and to a lesser extent, all-trans β-carotene, α-carotene, but not 9-cis β-carotene. The results suggest that irradiation increases the susceptibility of lipids to oxidation in the Chernobyl children and that natural β-carotene may act as an in vivo lipophilic antioxidant or radioprotector. Received: 20 March 1998 / Accepted in revised form: 1 August 1998  相似文献   

18.
This study aimed at comparing antioxidant potential of fucoxanthin (FUCO) with β-carotene in relieving lipid peroxidation (Lpx) caused by retinol deficiency (RD) in rats. RD rats (n = 45) were fed a dose of either β-carotene (0.81 μmol) or FUCO (0.83 μmol). Plasma and liver lipid peroxide levels and activity of antioxidant enzymes catalase (CAT) and glutathione transferase (GST) were measured for 8 h. Results revealed that RD increased (P < 0.05) Lpx in plasma and liver by 34.3% and 19.4%, while the CAT activity in plasma (89%) and liver microsomes (91%) and GST in liver homogenate (31%) and liver microsomes (30%) were decreased (P < 0.05) compared to control (rats fed basal diet). FUCO suppressed (P < 0.05) the Lpx level by 7–85% (plasma) and 24–72% (liver) as compared to β-carotene (51–76%, 33–65%) over a period of 8 h. The activity of CAT in plasma and liver microsomes was higher (P < 0.05) in FUCO (90–95%, 85–93%) and β-carotene (87–96%, 79–91%) groups as compared to RD group. Similarly, the activity of GST in liver and its microsomes was also elevated (P < 0.05) in FUCO (44–51%, 22–51%) and β-carotene (19–54%, 30–43%) groups as compared to RD group. Results demonstrate that FUCO has greater potential than β-carotene in modulating Lpx, CAT, GST in plasma and liver of RD rats.  相似文献   

19.
The aim of this analysis was to determine the relationship between monosodium glutamate (MSG) intake and change in hemoglobin (Hb) levels and the risk of anemia over 5?years in 1197 Chinese men and women who participated in the Jiangsu Nutrition Study (JIN). MSG intake and Hb were quantitatively assessed in 2002 and followed up in 2007. Diet and lifestyle factors were assessed at both time points. There was a positive association between MSG intake and increase in Hb among men but not women. In the multivariate model adjusting for demographic and lifestyle factors as well as baseline dietary pattern, the beta values and 95% confidence interval for Hb changes across quartiles of MSG intake were 0, 0.67(0.04-1.29), 0.99(0.38-1.60), 0.73(0.13-1.34) among men (p for trend 0.091); 0, -0.01(-0.45-0.43), 0.23(-0.25-0.71), and -0.45(-0.96-0.05) among women (p for trend 0.087). Among anemic participants at baseline, there was a significant inverse association between MSG intake and the risk of anemia at follow-up. Comparing extreme quartiles of MSG intake among those anemic at baseline, the relative risk for persistent anemia at follow-up was 0.49 (95% CI: 0.28-0.86, p?相似文献   

20.
Plasma retinol and α-tocopherol concentrations were measured in heparinized blood samples collected from 51 free-ranging adult Humboldt penguins (Sphenicus humboldti) residing at two colonies off the Chilean coast. Thirty samples were collected in April 1992 from penguins inhabiting the Ex-islote de los Pájaros Niños in Algarrobo, Chile. In September 1992, 21 samples were collected from birds inhabiting Isla de Cachagua, Chile. Samples were assayed for retinol, retinyl palmitate, α-tocopherol, γ-tocopherol, lutein, β-cryptoxanthin, lycopene, α-carotene, and β-carotene. Retinol, α-tocopherol, and lutein were detected in all samples, while lycopene and γ-tocopherol were not detected in any. A significantly higher percentage of samples had detectable levels of retinyl palmitate and α-carotene in April (P < 0.001): for β-cryptoxanthin the percentage was higher in September (P < 0.001). Plasma concentrations of α-tocopherol and lutein were higher in September. Alpha-tocopherol concentrations were 1,877.1 ± 99.0 (SEM) μg/dl in April compared to 2.289 ± 122.3 μg/dl in September (P < 0.05); lutein concentrations were 4.16 ± 0.43 μg/dl in April vs. 10.68 ± 1.02 μg/dl in September (P < 0.001). Retinol concentrations were not significantly different (117 ± 8.0 μg/dl in April vs. 105.3 ± 7.6 μg/dl in September). Both physiologic changes associated with season, and the change in locale may have contributed to the differences seen in the assay means and the number of samples with detectable levels. © 1996 Wiley-Liss, Inc.  相似文献   

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