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Featured researches published by Wolfgang Stuetz.


European Journal of Clinical Nutrition | 2014

Oxidative stress markers and micronutrients in maternal and cord blood in relation to neonatal outcome

Daniela Weber; Wolfgang Stuetz; W Bernhard; A Franz; M Raith; Tilman Grune; Nicolle Breusing

Background/objectives:Oxidative stress and micronutrient deficiencies have been related to lower birth weight (BW), small for gestational age (SGA) offspring and preterm delivery.Subjects/methods:The relation between neonatal outcome (BW, head circumference, SGA, preterm delivery) with markers of oxidative stress and micronutrients in maternal and cord blood was to be examined. Oxidative stress markers (protein carbonyls (PrCarb), 3-nitrotyrosine (3NT), malondialdehyde (MDA)), total protein concentration and lipid-soluble micronutrients (carotenoids, retinol, tocopherols) were measured in 200 newborns (11% preterms, 13% SGA) and 151 mothers. Associations between target parameters in cord plasma and maternal serum with BW, head circumference and risk of being SGA or preterm were explored.Results:Maternal protein concentration, PrCarb, MDA and all lipid-soluble micronutrients were significantly higher compared with newborns, except for 3NT, which was significantly elevated in newborns. Newborn parameters correlated positively with those of mothers. Preterms had lower proteins and retinol but higher PrCarb than terms. Maternal PrCarb and retinol were inversely associated with BW and head circumference. Mothers with PrCarb, MDA and retinol in the highest quintile had a 3.3-fold (0.9; 12.1), 2.1-fold (0.7; 6.4) and 3.3-fold (1.2; 9.4) risk, respectively, for delivering an SGA newborn, whereas the lowest quintile of retinol in cord blood was associated with an increased risk for preterm delivery.Conclusions:Oxidative stress (elevated PrCarb) was associated with lower BW/head circumference and SGA. Inadequate hemodilution may explain the inverse relation of maternal retinol with BW and head circumference, and the association between highest maternal retinol and risk for SGA.


PLOS ONE | 2012

Thiamine Diphosphate in Whole Blood, Thiamine and Thiamine Monophosphate in Breast-Milk in a Refugee Population

Wolfgang Stuetz; Verena I. Carrara; Rose McGready; Sue Jean Lee; Hans Konrad Biesalski; François Nosten

Background The provision of high doses of thiamine may prevent thiamine deficiency in the post-partum period of displaced persons. Methodology/Principal Findings The study aimed to evaluate a supplementation regimen of thiamine mononitrate (100 mg daily) at the antenatal clinics in Maela refugee camp. Women were enrolled during antenatal care and followed after delivery. Samples were collected at 12 weeks post partum. Thiamine diphosphate (TDP) in whole blood and thiamine in breast-milk of 636 lactating women were measured. Thiamine in breast-milk consisted of thiamine monophosphate (TMP) in addition to thiamine, with a mean TMP to total thiamine ratio of 63%. Mean whole blood TDP (130 nmol/L) and total thiamine in breast-milk (755 nmol/L) were within the upper range reported for well-nourished women. The prevalence of women with low whole blood TDP (<65 nmol/L) was 5% and with deficient breast-milk total thiamine (<300 nmol/L) was 4%. Whole blood TDP predicted both breast-milk thiamine and TMP (R2 = 0.36 and 0.10, p<0.001). A ratio of TMP to total thiamine ≥63% was associated with a 7.5 and 4-fold higher risk of low whole blood TDP and deficient total breast-milk thiamine, respectively. Routine provision of daily 100 mg of thiamine mononitrate post-partum compared to the previous weekly 10 mg of thiamine hydrochloride resulted in significantly higher total thiamine in breast-milk. Conclusions/Significance Thiamine supplementation for lactating women in Maela refugee camp is effective and should be continued. TMP and its ratio to total thiamine in breast-milk, reported for the first time in this study, provided useful information on thiamine status and should be included in future studies of breast-milk thiamine.


High Pressure Research | 2011

High pressure-assisted encapsulation of vitamin D2 in reassembled casein micelles

Orquídea Menéndez-Aguirre; Wolfgang Stuetz; Tilman Grune; Anne Kessler; Jochen Weiss; Jörg Hinrichs

For the encapsulation of vitamin D2, native casein micelles and vitamin D2 with or without additional Ca2+–Pi were treated at 600 MPa and 37 °C for 60 min. The pressure release rate was set at 20 or 600 MPa/min. Vitamin D2 was quantified by reversed-phase high-performance liquid chromatography, and physical properties of the micelles were analysed by photon correlation spectroscopy. The results demonstrate that simultaneous application of Ca2+–Pi and high pressure treatment with a fast release rate significantly increased loading of vitamin D2 per casein by 6.9-fold. The addition of Ca2+–Pi enhanced micelle aggregation and the vitamin was entrapped within the formed aggregates. However, high pressure treatment without Ca2+–Pi with a slow pressure release rate revealed similar results, increasing vitamin D2 per casein by 6.7-fold. The vitamin D2 loading in reassembled casein micelles is supposed to be due to hydrophobic interactions between the hydrophobic domains of the micelles.


International Breastfeeding Journal | 2012

High initiation and long duration of breastfeeding despite absence of early skin-to-skin contact in Karen refugees on the Thai-Myanmar border: a mixed methods study

Adrienne White; Verena I. Carrara; Moo Kho Paw; Malika; ColleyPaw Dahbu; Mechthild M. Gross; Wolfgang Stuetz; François Nosten; Rose McGready

BackgroundEarly skin-to-skin contact (SSC) after birth is recommended as part of the United Nations Children’s Fund (UNICEF) baby friendly health initiative to promote optimum breastfeeding. This paper reports rates of breastfeeding initiation and duration in a low resource environment, where early SSC is not practised, and explores views of pregnant women and midwives surrounding breastfeeding and swaddling.MethodsData from records from a single hospital on the Thai-Myanmar border where refugee women gave birth during a one-year period (2010) were used to determine breastfeeding initiation rates and the time of the first breastfeed, and duration of breastfeeding of the previous alive child in multigravidae. Focus group discussions (FGD) were conducted to obtain information from pregnant women attending antenatal care about their intended or previous duration of breastfeeding and views on breastfeeding. Interviews with local midwives explored reasons for high rates of breastfeeding in this setting and the practice of newborn swaddling.ResultsOf 1404 live births in 2010 in Maela refugee camp there were 982 evaluable mother-newborn pairs, including 80 infants born before 37 weeks gestation. Initiation of breastfeeding within the first hour after birth and exclusive breastfeeding at discharge in term mother-newborn pairs was 91.2% (823/902) and 99.3% (896/902); and before 37 weeks gestation, 48.8% (39/80) and 98.8% (79/80). Reported duration of previous breastfeeding was 19 (range 2 to 72) months.During FGD all primigravidae (n = 17) intended to breastfeed and all multigravidae (n = 33) had previously breastfed; expected or previous duration of feeding was for more than one year or longer. The major theme identified during FGD was breastfeeding is “good”. Women stated their intention to breastfeed with certainty. This certainty was echoed during the interviews with midwifery staff. SSC requires a delay in early swaddling that in Karen people, with animistic beliefs, could risk loss of the spirit of the newborn or attract malevolent spirits.ConclusionsIn a population with a strong culture of breastfeeding and robust breastfeeding practices, high rates of initiation and duration of breastfeeding were found despite a lack of early skin-to-skin contact. Local preferences, traditions and practices that protect, support and maintain high rates of breastfeeding should be promoted.


Food Research International | 2014

Increased loading of vitamin D2 in reassembled casein micelles with temperature-modulated high pressure treatment

Orquídea Menéndez-Aguirre; Anne Kessler; Wolfgang Stuetz; Tilman Grune; Jochen Weiss; Jörg Hinrichs

Native casein micelles were treated (incubated) with vitamin D2 at different hydrostatical pressures (0.1, 200, 400, and 600MPa) and temperatures (10-50°C) in order to load the vitamin. Pressure induced the release of αs-, β- and κ-casein and calcium from the micelle into the soluble phase. During the pressure stable reassembled micelles were created due to a structural rearrangement of hydrophobic interactions between the hydrophobic domains of the caseins and vitamin D2. Treatment at 600MPa and 50°C increased the loading of vitamin D2 per casein from 2.2±0.2μg/mg (native sample) to 10.4±0.2μg/mg. The reassembled micelles presented an average hydrodynamic diameter of 272±10nm and contained 8.1, 10.3 and 0.8mg of α-, β- and κ-casein, respectively, per 100mg casein.


International Journal of Food Sciences and Nutrition | 2012

Bioactive compounds extracted from Indian wild legume seeds: antioxidant and type II diabetes–related enzyme inhibition properties

Basanta Gautam; Vellingiri Vadivel; Wolfgang Stuetz; Hans Konrad Biesalski

Seven different wild legume seeds (Acacia leucophloea, Bauhinia variegata, Canavalia gladiata, Entada scandens, Mucuna pruriens, Sesbania bispinosa and Tamarindus indica) from various parts of India were analyzed for total free phenolics, l-Dopa (l-3,4 dihydroxyphenylalanine), phytic acid and their antioxidant capacity (ferric-reducing antioxidant power [FRAP] and 2,2-diphenyl-1-picrylhydrazyl [DPPH] assay) and type II diabetes–related enzyme inhibition activitiy (α-amylase). S. bispinosa had the highest content in both total free phenolics and l-Dopa, and relatively low phytic acid when compared with other seeds. Phytic acid content, being highest in E. scandens, M. pruriens and T. indica, was highly predictive for FRAP (r = 0.47, p < 0.05) and DPPH (r = 0.66, p < 0.001) assays. The phenolic extract from T. indica and l-Dopa extract from E. scandens showed significantly higher FRAP values among others. All seed extracts demonstrated a remarkable reducing power (7–145 mM FeSO4 per mg extract), DPPH radical scavenging activity (16–95%) and α-amylase enzyme inhibition activity (28–40%).


Food Chemistry | 2017

B-vitamins, carotenoids and α-/γ-tocopherol in raw and roasted nuts

Wolfgang Stuetz; Wiebke Schlörmann; Michael Glei

The concentrations of B-vitamins, carotenoids and tocopherols in nuts may differ between species and might be influenced by roasting. Thiamine, riboflavin, pyridoxine, lutein, zeaxanthin, β-carotene and α-/γ-tocopherol were determined in different varieties of raw and roasted nuts using HPLC (fluorescence/UV-vis detection). The analysis revealed remarkable concentrations of thiamine and pyridoxine in pistachios (57%, 79% of the recommended daily intake/100g (RDI), respectively) and riboflavin in almonds (119% of the RDI). Pistachios were rich in lutein/zeaxanthin and contained highest β-carotene levels among nuts. Almonds and hazelnuts were abundant in α-tocopherol (>4-fold the RDI for tocopherol equivalents) while pistachios and walnuts were rich in γ-tocopherol. Roasting had a diminishing effect on thiamine, carotenoids and tocopherols especially in almonds and walnuts. Nuts could make a valuable contribution to a healthy diet in regard to B-vitamins, lutein/zeaxanthin and tocopherols. A reduction in micronutrient content by roasting is reliant on the nut variety and specific micronutrient.


Nutrients | 2016

Plasma Carotenoids, Tocopherols, and Retinol in the Age-Stratified (35–74 Years) General Population : A Cross-Sectional Study in Six European Countries

Wolfgang Stuetz; Daniela Weber; Martijn E.T. Dollé; Eugene Jansen; Beatrix Grubeck-Loebenstein; Simone Fiegl; Olivier Toussaint; Juergen Bernhardt; Efstathios S. Gonos; Claudio Franceschi; Ewa Sikora; Maria Moreno-Villanueva; Nicolle Breusing; Tilman Grune; Alexander Bürkle

Blood micronutrient status may change with age. We analyzed plasma carotenoids, α-/γ-tocopherol, and retinol and their associations with age, demographic characteristics, and dietary habits (assessed by a short food frequency questionnaire) in a cross-sectional study of 2118 women and men (age-stratified from 35 to 74 years) of the general population from six European countries. Higher age was associated with lower lycopene and α-/β-carotene and higher β-cryptoxanthin, lutein, zeaxanthin, α-/γ-tocopherol, and retinol levels. Significant correlations with age were observed for lycopene (r = −0.248), α-tocopherol (r = 0.208), α-carotene (r = −0.112), and β-cryptoxanthin (r = 0.125; all p < 0.001). Age was inversely associated with lycopene (−6.5% per five-year age increase) and this association remained in the multiple regression model with the significant predictors (covariables) being country, season, cholesterol, gender, smoking status, body mass index (BMI (kg/m2)), and dietary habits. The positive association of α-tocopherol with age remained when all covariates including cholesterol and use of vitamin supplements were included (1.7% vs. 2.4% per five-year age increase). The association of higher β-cryptoxanthin with higher age was no longer statistically significant after adjustment for fruit consumption, whereas the inverse association of α-carotene with age remained in the fully adjusted multivariable model (−4.8% vs. −3.8% per five-year age increase). We conclude from our study that age is an independent predictor of plasma lycopene, α-tocopherol, and α-carotene.


European Journal of Clinical Nutrition | 2013

5-Methyltetrahydrofolate and thiamine diphosphate in cord-blood erythrocytes of preterm versus term newborns.

Daniela Weber; Wolfgang Stuetz; W Bernhard; A Franz; M Raith; Tilman Grune; Nicolle Breusing

Background/objectives:A low folate or low thiamine status may be associated with the risk of preterm delivery, small for gestational age (SGA) offspring and adverse pregnancy outcomes.Subjects/methods:5-Methyltetrahydrofolate (5MTHF) and thiamine diphosphate (TDP) were measured directly in cord-blood erythrocytes (CBEs) of early preterm (n=26; <32 weeks gestational age; including 50% multiple births), late preterm (n=38; 32 to <37 weeks; including 24% multiple births) and term newborns (n=60, 37–42 weeks) via high-performance liquid chromatography and fluorescence detection. Associations between 5MTHF and TDP with gestational age, newborn anthropometrics (birth weight, newborn’s length and head circumference) and risk of being SGA were explored.Results:Group comparison as well as multivariate linear regression analysis of cord-blood vitamins revealed that 5MTHF was significantly lower in late preterms compared with terms but did not differ between singletons and multiples. TDP tended to be higher in preterms than in terms and lower in multiples than in singletons in both early and late preterms. Multivariate analysis on birth outcomes showed that 5MTHF was significantly positively associated with gestational age, birth weight and newborn’s length. 5MTHF, increasing gestational age and parity were associated with a significantly reduced risk for being SGA, while TDP, multiple births and gender were not associated with the risk for being SGA.Conclusions:Higher CBE concentrations of 5MTHF were associated with improved birth outcomes. Lower TDP concentrations were observed in multiple births. Future studies evaluating cord-blood vitamin concentrations and their associations with birth outcomes should additionally include dietary intakes and maternal blood concentrations at different stages of pregnancy.


Oxidative Medicine and Cellular Longevity | 2017

Associations between Specific Redox Biomarkers and Age in a Large European Cohort: The MARK-AGE Project

Daniela Weber; Wolfgang Stuetz; Olivier Toussaint; Florence Debacq-Chainiaux; Martijn E.T. Dollé; Eugene Jansen; Efstathios S. Gonos; Claudio Franceschi; Ewa Sikora; Antti Hervonen; Nicolle Breusing; Thilo Sindlinger; Maria Moreno-Villanueva; Alexander Bürkle; Tilman Grune

Oxidative stress and antioxidants play a role in age-related diseases and in the aging process. We here present data on protein carbonyls, 3-nitrotyrosine, malondialdehyde, and cellular and plasma antioxidants (glutathione, cysteine, ascorbic acid, uric acid, α-tocopherol, and lycopene) and their relation with age in the European multicenter study MARK-AGE. To avoid confounding, only data from countries which recruited subjects from all three study groups (five of eight centers) and only participants aged ≥55 years were selected resulting in data from 1559 participants. These included subjects from (1) the general population, (2) members from long-living families, and (3) their spouses. In addition, 683 middle-aged reference participants (35–54 years) served as a control. After adjustment for age, BMI, smoking status, gender, and country, there were differences in protein carbonyls, malondialdehyde, 3-nitrotyrosine, α-tocopherol, cysteine, and glutathione between the 3 study groups. Protein carbonyls and 3-nitrotyrosine as well as cysteine, uric acid, and lycopene were identified as independent biomarkers with the highest correlation with age. Interestingly, from all antioxidants measured, only lycopene was lower in all aged groups and from the oxidative stress biomarkers, only 3-nitrotyrosine was increased in the descendants from long-living families compared to the middle-aged control group. We conclude that both lifestyle and genetics may be important contributors to redox biomarkers in an aging population.

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Martijn E.T. Dollé

University of Texas Health Science Center at San Antonio

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