Development and simulated validation of a food-frequency questionnaire for the Colombian population

OBJECTIVE: To develop a food-frequency questionnaire (FFQ) useful for ranking of nutrient intakes. DESIGN: Subjects consuming their regular diet completed 7 days of weighed intake registry (7-WIR). Foods for the FFQ were selected by stepwise multiple regression. The FFQ was then completed for each subject using data on individual food consumption from the 7-WIR. The correlation and agreement between the extrapolated FFQ and the 7-WIR data were assessed using Spearman's rank correlation coefficients (rS) and Bland and Altman's limits of agreement (LOA). SETTING: Bucaramanga, Colombia. SUBJECTS: We studied 97 randomly selected 20-40-year-old subjects. RESULTS: Sixty foods were selected for the FFQ. The 7-WIR and the extrapolated FFQ intake estimates correlated well. rS was 0.58 for energy, 0.53 for carbohydrate, 0.50 for total fat, and 0.48 for protein. For micronutrients, rS varied from 0.46 (manganese) to 0.71 (vitamin B12). FFQ average intake estimates were 83%, 80%, 86.2% and 86.4% of 7-WIR estimates for energy, carbohydrate, total fat and protein, respectively. LOA for these nutrients ranged between 45% and 165%. FFQ micronutrient intakes were on average 96% (median) of those from the 7-WIR, and the median lower and upper LOA were 50% and 203%. However, there was no indication that the degree of agreement varied with the level of intake. CONCLUSIONS: According to our simulated validation, this FFQ may be useful to rank subjects by nutrient intake. Its validity against standard independent measurements and its applicability to other subsets of the Colombian population should be carefully considered.     

Development and validation of a food-frequency questionnaire for the determination of detailed fatty acid intakes

OBJECTIVE: To validate a fat intake questionnaire (FIQ) developed to assess habitual dietary intake while focusing on the assessment of detailed fatty acid intake including total trans unsaturated fatty acids (TUFA). DESIGN: An 88 food item/food group FIQ was developed using a meal pattern technique. Validation was achieved by comparison with dietary intake assessed by a modified diet history (DH) in a cross-over design. Eighty-four individuals supplied adipose tissue biopsies for linoleic acid and total TUFA analysis as an independent validation of the FIQ and DH. SETTING: Medical Centre, Dublin Airport, Republic of Ireland. SUBJECTS: One hundred and five healthy volunteers (43 females and 62 males aged 23-63 years). RESULTS: Significant correlations (P<0.0005) were achieved for intakes of energy (0.78), total fat (0.77), saturated fat (0.77), monounsaturated fat (0.63), polyunsaturated fat (0.73), TUFA (0.67) and linoleic acid (0.71) assessed by the FIQ compared with the DH. Linoleic acid intake assessed by the FIQ and the DH was significantly correlated with adipose tissue concentrations (r=0.58 and 0.49, respectively; P<0.005); however, total TUFA intake was poorly correlated with adipose tissue concentrations (r=0.17 and 0.10 for FIQ and DH, respectively). CONCLUSIONS: The FIQ compared favourably with the DH in assessing habitual diet, in particular fatty acid intake. In addition, the FIQ was successfully validated against the linoleic acid composition of adipose tissue, an independent biomarker of relative fatty acid status. The FIQ could therefore be used as an alternative to the DH as it is a shorter, less labour-intensive method.     

Carotenoid intakes, assessed by food-frequency questionnaires (FFQs), are associated with serum carotenoid concentrations in the Jackson Heart Study: validation of the Jackson Heart Study Delta NIRI Adult FFQs

OBJECTIVES: Intake and status of carotenoids have been associated with chronic disease. The objectives of this study were to examine the association between carotenoid intakes as measured by two regional food-frequency questionnaires (FFQs) and their corresponding measures in serum, and to report on dietary food sources of carotenoids in Jackson Heart Study (JHS) participants. DESIGN: Cross-sectional analysis of data for 402 African American men and women participating in the Diet and Physical Activity Sub-Study (DPASS) of the JHS. RESULTS: Mean serum carotenoid concentrations and intakes in this population were comparable to those reported for the general US population. After adjustment for covariates, correlations between serum and dietary measures of each carotenoid, for the average of the recalls (deattenuated), the short FFQ and the long FFQ, respectively, were: 035 and 0-carotene; 026 and 0-carotene; 017 and 0-carotene; 034 and 0-cryptoxanthin; 015 and 037, 014 for lycopene. Major dietary sources of -carotene and lutein plus zeaxanthin, mustard, turnip and collard greens; of beta-cryptoxanthin, orange juice; and of lycopene, tomato juice. CONCLUSIONS: On average, carotenoid intakes and serum concentrations are not lower in this southern African American population than the general US population. The two regional FFQs developed for a southern US population and used as dietary assessment tools in the JHS appear to provide reasonably valid information for most of these carotenoids.     

Validity and reproducibility of two semi-quantitative alcohol frequency questionnaires for the Colombian population

OBJECTIVE: To determine the relative validity and reproducibility of two alcohol intake frequency questionnaires (AFQ-A; AFQ-B), designed to classify subjects according to their alcohol intake level, in Bucaramanga, Colombia. METHOD: One hundred and nine randomly selected subjects, aged between 20 and 60 years, completed three 30-day semi-quantitative alcohol intake records (30-DR). The AFQs were applied three months after the last 30-DR. AFQ-A contained 53 items; AFQ-B contained five items, with the alcoholic drinks for AFQ-B selected by Max_r. The correlation and agreement between alcohol intake assessed with the AFQs and the 30-DR were obtained using Pearson's correlation coefficient (r), Lin's concordance correlation coefficient (rhoC), Spearman's rank correlation coefficient (rS), Bland and Altman's limits of agreement (LOA) and Cohen's weighted kappa statistic (Kw). RESULTS: The reproducibility of the 30-DR was poor; rS ranged from 0.33 to 0.41. The reproducibility of the AFQs was higher, with rS between 0.50 and 0.73. The agreement (Kw) of the 30-DR and the AFQs was 0.40. The lower and upper LOA were between -56.4% and -11.0%. The AFQs and 30-DR were well correlated. Assessment of relative validity between the two methods yielded r values for alcohol between 0.52 and 0.60, which reduced to 0.20-0.29 after energy adjustment. CONCLUSIONS: These AFQs may be useful to rank subjects according to their alcohol intake. The AFQ-B is easy and quick to apply, and is also highly cost-effective.     

Prevalence of obesity, food choices and socio-economic status: a cross-sectional study in the north-west of Iran

AIM: To document the epidemiological features and influencing factors of obesity in the north-west of Iran, to provide baseline information for setting up a regional population-based centre to control and prevent obesity-related disorders in the area. METHODS: In this cross-sectional study, a total of 300 subjects were selected/studied in Tabriz, one of the major cities in Iran. Data on basic characteristics, anthropometric measurements, dietary assessment and physical activity were collected. Obesity was defined as body mass index > or =30 kg m(-2) for both women and men. RESULTS: Total prevalence of obesity in the area was 22.4% (95% confidence interval (CI): 18.0-27.6). The prevalence of obesity was 24% (95% CI: 18.5-31.4) for women and 18% (95% CI: 12.5-25.6) for men. For both women and men obesity prevalence showed a positive association with age (P<0.001), while there was a negative correlation of obesity with education and income (P<0.001). Fruit consumption decreased the risk of obesity in both women and men (odds ratio (OR)=0.60, 95% CI: 0.49-0.71 vs. OR=0.62, 95% CI: 0.51-0.74, respectively). The same significant pattern was observed for the consumption of green vegetables (OR=0.71, 95% CI: 0.57-0.63 vs. OR=0.86, 95% CI: 0.77-0.98 for women and men, respectively), legumes (OR=0.70, 95% CI: 0.59-0.84 vs. OR=0.78, 95% CI: 0.66-0.91 for women and men, respectively) and dairy products (OR=0.73, 95% CI: 0.61-0.91 vs. OR=0.77, 95% CI: 0.63-0.93 for women and men, respectively). CONCLUSIONS: Our study showed that educational attainment, higher income and consumption of certain food groups (i.e. vegetables, fruits, legumes and dairy products) may decrease the risk of obesity. Our findings also indicate the crucial necessity of establishing a population-based centre for obesity in the area. The essential information is now achieved to propose to local health authorities to act accordingly. However, more population-based investigations on dietary choices are needed to develop effective preventive strategies to control overweight and obesity disorders in different regions.     

Mini Nutritional Assessment of rural elderly people in Bangladesh: the impact of demographic, socio-economic and health factors

OBJECTIVE: In stating the Millennium Development Goals, the United Nations aims to halve malnutrition around the world by 2015. Nutritional status of the elderly population in low-income countries is seldom focused upon. The present study aimed to evaluate the magnitude of malnutrition among an elderly population in rural Bangladesh. DESIGN AND SETTING: Data collection for a multidimensional cross-sectional study of community-based elderly people aged 60 years and over was conducted in a rural area in Bangladesh. SUBJECTS: Of 850 randomly selected elderly individuals, 625 participated in home interviews. Complete nutritional information was available for 457 individuals (mean age 69+/-8 years, 55% female). Nutritional status was assessed using an adapted form of the Mini Nutritional Assessment (MNA) including body mass index (BMI). Age, sex, education, household expenditure on food and self-reported health problems were investigated as potential predictors of nutritional status. RESULTS: BMI<18.5 kg m(-2), indicating chronic energy deficiency, was found in 50% of the population. MNA revealed a prevalence of 26% for protein-energy malnutrition and 62% for risk of malnutrition. Health problems rather than age had a negative impact on nutritional status. Level of education and food expenditure were directly associated with nutritional status. CONCLUSION: In order to reduce world hunger by half in the coming decade, it is important to recognise that a substantial proportion of the elderly population, particularly in low-income countries, is undernourished.     

Differential copper impact on density,diversity and resistance of adapted culturable bacterial populations according to soil organic status

The effect of copper on the abundance, diversity and resistance of viable heterotrophic and copper resistant bacterial populations (Cu^R) was evaluated in soils differing only by their amount and type of organic matter. These soils have been obtained using a vineyard soil that had been subjected to three different organic matter managements (Not Amended (NA) or amended with Straw (S) or Conifer Compost (CC)) in a long term field experiment. Soil microcosms were artificially contaminated with copper (250 mg Cu kg^?1 of soil) and incubated for 35 days. Throughout the incubation, a differential copper impact on viable heterotrophic and Cu^R bacterial enumeration was demonstrated according to the soil organic status with a magnitude which followed the order: NA > CC ≥ S. Diversity of Cu^R bacteria revealed no significant difference between the uncontaminated soils, as determined by 16S rRNA sequencing. However, copper spiking induced an enrichment of particular populations depending on soil, with Methylobacterium, Ralstonia and Staphylococcus like species becoming dominant in NA, S and CC soils, respectively. Evaluation of the copA gene distribution and diversity, through PCR detection and sequencing, revealed that few Cu^R bacteria (from 7 to 13%) possessed this genetic determinant before the addition of metal. Copper contamination induced an increase in the dissemination of homologous copA genes only in Ralstonia like species indigenous to S soils. From a functional point of view, copper minimum inhibitory concentration for each Cu^R strain was measured. It did not highlight variable copper resistance efficiency between strains belonging to different taxonomic groups, harboring or not the copA gene, and originating from different soils contaminated or not by copper.     

The effects of socio-economic status on BMI, waist:hip ratio and waist circumference in a group of Iranian women

OBJECTIVE: To assess the effects of socio-economic status (SES) on BMI, waist:hip ratio (WHR) and waist circumference (WC) in a group of Iranian women. METHODS: A cross-sectional study was conducted on 888 women in Sistan and Baluchestan Province. SES was measured using level of education. In addition, parity, marital status and physical activity were assessed. Standardized measurements were taken, BMI and WHR were calculated. RESULTS: Low education level was a strong determinant of overweight and obesity among Iranian women. After controlling for age, women with higher education level had significantly lower BMI, WC and parity. Multiple linear regression analysis found a significant negative association of BMI and WC with education level and a significant positive association of BMI and WC with parity. Significant factors associated with obesity by a logistic regression model were education level (OR for university graduates v. illiterate or low literacy levels: 1.00 v. 3.70; P = 0.01), living with spouse (OR for married v. single subjects: 1.00 v. 0.15; P = 0.05), parity (OR for more than five v. less than two pregnancies: 1.00 v. 0.34; P = 0.03) and WC (OR for < 0.88 cm v. > or = 0.88 cm: 1.00 v. 11.20; P = 0.001). CONCLUSION: The present study revealed that educational level, multiple pregnancies, marital status and lack of exercise are some possible explanations for the obesity among Sistan and Baluchestan women.     

Dietary intake of heterocyclic amines in relation to socio-economic, lifestyle and other dietary factors: estimates in a Swedish population

OBJECTIVES: To estimate the dietary intakes of heterocyclic amines (HCAs), to examine the intakes in relation to socio-economics, lifestyle and other dietary factors and to compare the classification of subjects by intake of HCA versus intake of meat and fish. DESIGN: Cross-sectional analysis within the Malm? Diet and Cancer (MDC) cohort. Data were obtained from a modified diet history, a structured questionnaire on socio-economics and lifestyle, anthropometric measurements and chemical analysis of HCAs. HCA intake was cross-classified against meat and fish intake. The likelihood of being a high consumer of HCAs was estimated by logistic regression analysis. Dietary intakes were examined across quintiles of HCA intake using analysis of variance. SETTING: Baseline examinations conducted in 1991-1994 in Malm?, Sweden. SUBJECTS: A sub-sample of 8599 women and 6575 men of the MDC cohort. RESULTS: The mean daily HCA intake was 583 ng for women and 821 ng for men. Subjects were ranked differently with respect to HCA intake compared with intake of fried and baked meat and fish (kappa = 0.13). High HCA intake was significantly associated with lower age, overweight, sedentary lifestyle and smoking. Intakes of dietary fibre, fruits and fermented milk products were negatively associated with HCA intake, while intakes of selenium, vegetables, potatoes, alcohol (among men) and non-milk-based margarines (among women) were positively associated with HCA intake. CONCLUSIONS: The estimated daily HCA intake of 690 ng is similar to values obtained elsewhere. The present study suggests that lifestyle factors (e.g. smoking, physical activity, fruit and vegetable intakes, and types of milk products and margarines) may confound associations between HCA intake and disease. The poor correlation between HCA intake and intakes of fried meat and fish facilitates an isolation of the health effects of HCAs.     

Nutritional status of the Andean population of Puna and Quebrada of Humahuaca, Jujuy, Argentina

OBJECTIVE: To assess the nutritional status of the Andean population of Puna and Quebrada of Humahuaca, Jujuy, using anthropometric measurements. DESIGN AND SUBJECTS: A cross-sectional nutritional survey was carried out in a representative sample (n = 1236) of individuals from these regions. Children aged 2-9 years, adolescents (10-17 years) and adults (>or=18 years; pregnant and lactating women excluded) were considered. Height-for-age, weight-for-height and body mass index (BMI) were calculated in children and adolescents and compared with World Health Organization/National Center for Health Statistics/Centers for Disease Control and Prevention reference standards using Z-scores or percentiles, in order to assess the prevalence of stunting, wasting/thinness and excess weight. In adults, BMI, waist circumference (WC) and waist-to-hip (WHR) ratio were used to identify obesity and central adiposity. RESULTS: Stunting (height-for-age Z-score <-2 standard deviations) and obesity (BMI >or= 95th percentile) were found to be major nutritional problems in children and adolescents. Stunting was prevalent in 10.7% of children and 12.4% of adolescents; 8.2% of children and 3.5% of adolescents were obese. Adults were short (mean: 155.8 cm) and values of overweight (32.3%), obesity (18.3%) and central adiposity (mean WC: 86.5 cm) were high. Older adults and those with higher economic development showed higher prevalence of obesity and central adiposity. CONCLUSIONS: The present population may be at the early stages of nutritional transition as symptoms of undernutrition and overnutrition coexist at the population level. These results suggest that rates of growth retardation may be decreasing owing to improved nutritional conditions; however, this could be accompanied by a sharp increase in the prevalence of other diet-related chronic diseases.     

Development and validation of an optical SPR biosensor assay for tylosin residues in honey

In recent years there has been an increase in the use of tylosin in apiculture as bacterial brood diseases become resistant to oxytetracycline. Confirmatory mass spectrometry based methods have been developed but up until now there has been no complementary screening method available capable of sub 10 microg kg(-1) detection limits. In this paper the development and validation of a screening method using optical biosensor technology is presented. The honey was first dissolved in a phosphate buffer and following solid-phase extraction (SPE) cleanup was analyzed using a Biacore Q instrument. Using the criteria specified in European Commission Decision 2002/657/EC for qualitative screening methods, the detection capability (CCbeta) of the method was determined to be 2.5 microg kg(-)(1). Honey samples containing trace residue levels of tylosin were analyzed by both the biosensor screening method and a LC-MS/MS confirmatory procedure; the results were in good agreement.     

Development and validation of an indirect competitive enzyme-linked immunosorbent assay for the screening of tylosin and tilmicosin in muscle, liver, milk, honey and eggs

Incorrect use of tylosin and tilmicosin could result in allergy and select resistance. To monitor the illegal use of these antibiotics in animals, a monoclonal-based indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) has been established. Several haptens were synthesized and conjugated to carrier protein. Female Balb/c mice were inoculated with the four different conjugates to produce monoclonal antibodies according to the schemes of immunization. Aftercell fusion and culture several times, nine hybridoma cell lines were isolated. Only one, 3C4 that has isotype IgG2a, was selected for detailed study. The cross-reactivity of the monoclonal antibody 3C4 to tylosin and tilmicosin was 100% and 51% respectively. The standard curves based on the tylosin and tilmicosin matrix calibration ranged from 2.5 to 40 μg L(-1), with an IC(50) value of 6.1 μg L(-1) and 12.1 μg L(-1), respectively. The limits of detection of the ic-ELISA ranged from 5.1 μg kg(-1) to 13.8 μg kg(-1) in edible animal tissues. The recoveries were 74.1% to 120.7% with less than 18.6% of the coefficient of variation when tylosin and tilmicosin were spiked in various biological matrices with the concentrations of 25.0-200.0 μg kg(-1). Good correlations between the results of the ic-ELISA and high performance liquid chromatography were observed in the incurred tissues. These results suggest that the ic-ELISA is a sensitive, accurate and low-cost method that would be a useful tool for the screening of the residues of tylosin and tilmicosin in muscle, liver, milk, honey and eggs.     

Comparative studies of plant and soil analysis for the sulphur status of oilseed rape and winter wheat

Recently S deficiency became one of the most widespread nutrient disorders in North-European agriculture. Therefore precise and reliable methods for the evaluation of the S nutritional status of agricultural crops are required. For the prognosis of the plant available S soil analysis would be a favourite method, however, no relation between plant S concentrations and mobile (extractable sulphate plus extractable organic S) S contents in soils could be stated. The reasons for the impracticability of traditional soil tests seem to be related to interactions between soil water and mobile S in soils, so that site specific models need to be developed for the prognosis of the S status of agricultural crops.     

Development and validation of an ultrasensitive chemiluminescent enzyme immunoassay for aflatoxin M1 in milk

A fast and ultrasensitive chemiluminescent enzyme immunoassay for aflatoxin M(1) in milk samples has been developed and validated. The method is an indirect competitive type format involving the immobilization of an aflatoxin M(1)-bovine serum albumin conjugate on 384 well black polystyrene microtiter plates and the use of a secondary antibody labeled with horseradish peroxidase detected with a luminol-based substrate. Aflatoxin M(1) standard solutions were prepared in milk-based buffer, and milk samples were analyzed without any cleanup procedure. The limit of quantification was 1 ppt, the coefficient of variation was below 9% for both intra- and interassay precision, and the recovery ranged from 96 to 122%. The method is specific, and other aflatoxins do not significantly cross-react with the antibody. Twenty-four milk samples were analyzed, and a good correlation was observed (y = 0.98x + 1.71, r(2) = 0.98, n = 24) when the data were compared with a reference high-performance liquid chromatography method with a fluorescent detector. The developed method is suitable for an accurate, sensitive, and high-throughput screening of aflatoxin M(1) in milk samples with a reduction of costs and increased detectability, as compared with previously developed immunoassays.     

Synthesis of haptens and conjugates for ELISA of glycitein: development and validation of an immunological test

Two carboxylic acid haptens of glycitein were synthesized, with a spacer arm at the C2 position. They differed in the length of the spacer arm, with the length of the spacer arms being three or four carbon atoms, and were named Delta3-glycitein and Delta4-glycitein haptens, respectively. The different haptens were coupled to bovine serum albumin (BSA), and the coupling efficiency was assessed by MALDI mass spectrometry. Polyclonal antibodies were generated against the BSA conjugates. An additional conjugate of Delta4-glycitein hapten was generated with swine thyroglobulin (Thyr). Enzyme-linked immunosorbent assays (ELISAs) based on the competition between free glycitein and Delta4-glycitein-Thyr conjugates for specific antibodies were developed. The IC50 of the standard curves was 15.6 ng mL(-1) with anti-Delta3-glycitein and 62.5 ng mL(-1) with anti-Delta4-glycitein, that is, 10.9 and 44 pmol/well, respectively. With the Delta3-glycitein antibody, interassay and intra-assay variations were 12.2 and 11.5%, respectively. Specificity tests did not show any significant cross-reaction with any other soy isoflavone. This specificity is not influenced by the length of the spacer arm. The assay was validated by measurements performed on plasma samples as well as on soy-based foodstuffs and on soy-based food supplements.     

Nesting ecology, current status, and conservation of sea turtles on an uninhabited beach in Florida, USA

Although nesting beaches are critical resources for sea turtles, most beaches in the United States are disturbed by human influence, including human access, artificial lighting, and habitat alteration. In contrast, very few undisturbed beaches remain along the Atlantic coast, and these areas represent unique habitats that can help decipher the impacts of development on various species. We monitored nesting patterns and hatching success of three sea turtle species (Caretta caretta, Chelonia mydas, and Dermochelys coriacea) from 1985 to 2003 on Canaveral National Seashore, an uninhabited 38.3 km stretch of beach in Florida. We monitored the number of nests deposited annually, hatching success, predation rates, and spatial nesting patterns. Clutch sizes varied within, but not among years, most likely due to variation in size of nesting females rather than climate change or resource availability. The number of nests increased over the study period for all three species, indicating growing populations. Higher numbers of nests were deposited on the southern end of our beach than on the northern end. Hatching success did not vary by species, but was dependent on nest-protection effort, which increased during the study period. Protecting more nests with wire screens resulted in lower predation rates. We did not find any evidence suggesting that predators are using nest markers to locate eggs, even after using the same method of marking nests for 19 years. Our conservation efforts have lowered predation levels through increased screening effort, and over time the number of nests laid increased for each species. Collecting baseline data on nesting patterns in undisturbed locations will allow comparisons to be made on nesting trends and patterns at geographically close, but disturbed, localities.