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Volatile-mediated antagonism of soil bacterial communities against fungi
Li, Xiaogang ; Garbeva, Paolina ; Liu, Xiaojiao ; klein Gunnewiek, Paulien J.A. ; Clocchiatti, Anna ; Hundscheid, Maria P.J. ; Wang, Xingxiang ; Boer, Wietse de - \ 2019
Environmental Microbiology (2019). - ISSN 1462-2912
Competition is a major type of interaction between fungi and bacteria in soil and is also an important factor in suppression of plant diseases caused by soil-borne fungal pathogens. There is increasing attention for the possible role of volatiles in competitive interactions between bacteria and fungi. However, knowledge on the actual role of bacterial volatiles in interactions with fungi within soil microbial communities is lacking. Here, we examined colonization of sterile agricultural soils by fungi and bacteria from non-sterile soil inoculums during exposure to volatiles emitted by soil-derived bacterial communities. We found that colonization of soil by fungi was negatively affected by exposure to volatiles emitted by bacterial communities whereas that of bacteria was barely changed. Furthermore, there were strong effects of bacterial community volatiles on the assembly of fungal soil colonizers. Identification of volatile composition produced by bacterial communities revealed several compounds with known fungistatic activity. Our results are the first to reveal a collective volatile-mediated antagonism of soil bacteria against fungi. Given the better exploration abilities of filamentous fungi in unsaturated soils, this may be an important strategy for bacteria to defend occupied nutrient patches against invading fungi. Another implication of our research is that bacterial volatiles in soil atmospheres can have a major contribution to soil fungistasis.
Ionized and Total Magnesium Levels Change during Repeated Exercise in Older Adults
Terink, Rieneke ; Balvers, M.G. ; Bongers, C.C.W.G. ; Eijsvogels, T.M.H. ; Witkamp, R.F. ; Mensink, M. ; Hopman, M.T. ; Klein Gunnewiek, J.M.T. - \ 2019
Journal of Nutrition, Health and Aging 23 (2019)6. - ISSN 1279-7707 - p. 595 - 601.
consecutive exercise days - micronutrients - Older adults - reference values
Background: Magnesium is essential for health and performance. Sub-optimal levels have been reported for older persons. In addition, physical exercise is known to temporally decrease magnesium blood concentrations. Objective: To investigate these observations in conjunction we assessed total (tMg) and ionized magnesium (iMg) concentrations in plasma and whole blood, respectively, during 4 consecutive days of exercise in very old vital adults. Design: 68 participants (age 83.7±1.9 years) were monitored on 4 consecutive days at which they walked 30–40km (average ∼8 hours) per day at a self-determined pace. Blood samples were collected one or two days prior to the start of exercise (baseline) and every walking day immediately post-exercise. Samples were analysed for tMg and iMg levels. Results: Baseline tMg and iMg levels were 0.85±0.07 and 0.47±0.07 mmol/L, respectively. iMg decreased after the first walking day (−0.10±0.09 mmol/L, p<.001), increased after the second (+0.11±0.07 mmol/L, p<.001), was unchanged after the third and decreased on the final walking day, all compared to the previous day. tMg was only higher after the third walking day compared to the second walking day (p=.012). In 88% of the participants, iMg levels reached values considered to be sub-optimal at day 1, in 16% of the participants values were sub-optimal for tMg at day 2. Conclusion: Prolonged moderate intensity exercise caused acute effects on iMg levels in a degree comparable to that after a bout of intensive exercise. These effects were not associated with drop-out or health problems. After the second consecutive day of exercise, levels were returned to baseline values, suggesting rapid adaptation/resilience in this population.
Changes in Micronutrient Intake and Status, Diet Quality and Glucose Tolerance from Preconception to the Second Trimester of Pregnancy
Looman, M. ; Geelen, M.M.E.E. ; Samlal, Rahul A.K. ; Heijligenberg, Rik ; Klein Gunnewiek, Jacqueline T.M. ; Balvers, Michiel ; Wijnberger, Lia D.E. ; Brouwer-Brolsma, Elske ; Feskens, E.J.M. - \ 2019
Nutrients 11 (2019)2. - ISSN 2072-6643
Data on changes in dietary intake and related blood parameters throughout pregnancy are scarce; moreover, few studies have examined their association with glucose homeostasis. Therefore, we monitored intake of folate, vitamin B6, vitamin B12, vitamin D and iron, their status markers, and diet quality from preconception to the second trimester of pregnancy, and we examined whether these dietary factors were associated with glucose homeostasis during pregnancy. We included 105 women aged 18–40 years with a desire to get pregnancy or who were already <24 weeks pregnant. Women at increased gestational diabetes (GDM) risk were oversampled. Measurements were scheduled at preconception (n = 67), and 12 (n =53) and 24 weeks of pregnancy (n =66), including a fasting venipuncture, 75-grams oral glucose tolerance test, and completion of a validated food frequency questionnaire. Changes in micronutrient intake and status, and associations between dietary factors and glucose homeostasis, were examined using adjusted repeated measures mixed models. Micronutrient intake of folate, vitamin B6 and vitamin D and related status markers significantly changed throughout pregnancy, which was predominantly due to changes in the intake of supplements. Micronutrient intake or status levels were not associated with glucose homeostasis, except for iron intake (FE µg/day) with fasting glucose (β = −0.069 mmol/L, p = 0.013) and HbA1c (β = −0.4843 mmol, p = 0.002). Diet quality was inversely associated with fasting glucose (β = −0.006 mmol/L for each DHD15-index point, p = 0.017). It was shown that micronutrient intakes and their status markers significantly changed during pregnancy. Only iron intake and diet quality were inversely associated with glucose homeostasis.
Determinants of vitamin D status in physically active elderly in the Netherlands
Haaf, D.S.M. ten; Balvers, M.G.J. ; Timmers, S. ; Eijsvogels, T.M.H. ; Hopman, M.T.E. ; Klein Gunnewiek, J.M.T. - \ 2019
European Journal of Nutrition 58 (2019)8. - ISSN 1436-6207 - p. 3121 - 3128.
25(OH)D - Determinant - Dietary intake - Elderly - Physical activity - Vitamin D status
Purpose: Vitamin D deficiencies are common in elderly, which increases the risk for, e.g., bone fractures. Identification of determinants of vitamin D status may provide leads for specific deficiency prevention strategies. Although determinants of vitamin D status have been studied in various populations, this has not been examined in elderly that have a physically active lifestyle. Methods: Vitamin D status of 450 physically active elderly who do not use vitamin D supplements was determined and information on possible determinants (demographic, dietary intake and physical activity) was collected around a prolonged four day walking event in July and analyzed in linear regression models. Results: The average summertime serum 25(OH)D concentration was 88.8 ± 22.4 nmol/L. Only 2% of the participants had a 25(OH)D concentration below 50 nmol/L. Dietary intake of vitamin D was 4.0 ± 1.9 µg/day, and the participants spent 12.4 ± 8.6 h/week on outdoor activities. In the multivariate model, lower age (= − 0.48, 95% CI − 0.80 to − 0.16), lower BMI (= − 0.86, 95% CI − 1.62 to − 0.10), being a moderate to high drinker versus a non-drinker (= 7.97, 95% CI 0.43–15.51) and more outdoor physical activity (= 0.25, 95% CI 0.01–0.50) were significantly associated with higher 25(OH)D concentrations. Conclusions: In physically active elderly, vitamin D status was very high in summertime, with few deficiencies, suggesting that elderly with a physical active lifestyle might not necessarily need supplements during the summer period. Lower age, lower BMI, higher alcohol intake and more outdoor physical activity had a significant association with vitamin D status.
Changes in iron metabolism during prolonged repeated walking exercise in middle-aged men and women
Terink, Rieneke ; Haaf, D. ten; Bongers, C.W.G. ; Balvers, M.G.J. ; Witkamp, R.F. ; Mensink, M. ; Eijsvogels, T.M.H. ; Klein Gunnewiek, J.M.T. ; Hopman, M.T.E. - \ 2018
European Journal of Applied Physiology 118 (2018)11. - ISSN 1439-6319 - p. 2349 - 2357.
Fe - Hb - Hp - Repetitive exercise
Purpose: The aim of the present study was to assess the effect of prolonged and repeated exercise on iron metabolism in middle-aged adults and to compare differences between sexes. Methods: 50 male (58.9 ± 9.9 year) and 48 female (50.9 ± 11.2 year) individuals were monitored on 4 consecutive days at which they walked on average 8 h and 44 min per day at a self-determined pace. Blood samples were collected 1 or 2 days prior to the start of the exercise (baseline) and every day immediately post-exercise. Samples were analysed for iron, ferritin, haemoglobin, and haptoglobin concentrations. Results: Plasma iron decreased across days, while ferritin increased across days (both p < 0.001). Haptoglobin showed a decrease (p < 0.001) after the first day and increased over subsequent days (p < 0.001). Haemoglobin did not change after the first day, but increased during subsequent days (p < 0.05). At baseline, 8% of the participants had iron concentrations below minimum reference value (10 µmol/L), this increased to 43% at day 4. There was an interaction between sex and exercise days on iron (p = 0.028), ferritin (p < 0.001) and haemoglobin levels (p = 0.004), but not on haptoglobin levels. Conclusion: This study showed decreases in iron, increases in ferritin, a decrease followed by increases in haptoglobin and no change followed by increases in haemoglobin. This is most likely explained by (foot strike) haemolysis, inflammation, and sweat and urine losses. These processes resulted in iron levels below minimum reference value in a large number of our participants.
Supplement use and dietary sources of folate, vitamin D, and n-3 fatty acids during preconception : The GLIMP2 study
Looman, Moniek ; Berg, Claudia van den; Geelen, Anouk ; Samlal, Rahul A.K. ; Heijligenberg, Rik ; Klein Gunnewiek, Jacqueline M.T. ; Balvers, Michiel G.J. ; Leendertz-Eggen, Caroline L. ; Wijnberger, Lia D.E. ; Feskens, Edith J.M. ; Brouwer-Brolsma, Elske M. - \ 2018
Nutrients 10 (2018)8. - ISSN 2072-6643
Diet - Folate - N-3 fatty acids - Preconception - Supplements - Vitamin D
An adequate nutritional status during the preconception period is important, particularly for folate, vitamin D, and n-3 fatty acids (i.e., EPA+DHA). We aimed to determine supplement intake and the main dietary sources of folate, vitamin D, and EPA+DHA using the data of 66 Dutch women aged 18–40 years who wished to become pregnant. Additionally, associations of these intakes with their blood levels were examined. Dietary intake was assessed with a validated food frequency questionnaire, and supplement use with a structured questionnaire. 25-hydroxyvitamin D levels were determined in serum and folate and phospholipid EPA+DHA levels in plasma. Partial Spearman’s correlations, restricted cubic splines and trend analyses over tertiles of nutrient intakes were performed to examine intake-status associations. A large proportion of women did not meet the Dutch recommended intakes of folate (50%), vitamin D (67%), and EPA+DHA (52%). Vegetables were the main contributor to dietary folate intake (25%), oils and fats to dietary vitamin D intake (39%), and fish to dietary EPA+DHA intake (69%). Fourteen percent of the women had an inadequate folate status and 23% an inadequate vitamin D status. Supplemental folate intake, supplemental and dietary vitamin D intake and dietary EPA+DHA intake were significantly associated with their blood levels. In conclusion, even in our highly educated population, a large proportion did not achieve recommended folate, vitamin D and n-3 fatty acid intakes. Promotion of folate and vitamin D supplement use and fish consumption is needed to improve intakes and blood levels of these nutrients in women who wish to become pregnant.
Fungal diversity and potential tree pathogens in decaying logs and stumps
Wal, Annemieke van der; klein Gunnewiek, Paulien ; Hollander, Mattias de; Boer, Wietse de - \ 2017
Forest Ecology and Management 406 (2017). - ISSN 0378-1127 - p. 266 - 273.
Fungal diversity - Fungal tree pathogens - Heartwood - Illumina MiSeq sequencing of ITS - LOGLIFE - Wood decomposition
Different types of dead wood in forest ecosystems contribute to an increase of habitats for decomposer fungi. This may have a positive effect on fungal diversity but may also increase habitats for tree pathogens. In this study we investigate the fungal diversity and composition via high-throughput sequencing in decaying stumps and logs (three years after cutting) of two tree species (Larix kaempferi and Quercus rubra) in a forest site. Fungal diversity and composition in decaying wood was different between tree species, between stumps and logs of the same tree species, and between sapwood and heartwood. When different wood sources were combined, fungal species diversity increased. This indicates that different wood sources contribute to fungal diversity and, therefore, species conservation in forests. Potential fungal tree pathogens were found in L. kaempferi stumps and logs, whereas their occurrence was generally less in Q. rubra wood sources. No clear difference was found in the relative abundance of potential fungal tree pathogens between stumps and logs, but some potential tree pathogens were only found in either stumps or logs. This indicates that both logs and stumps can be habitats for potential fungal tree pathogens, and each wood type seems to harbor different fungal tree pathogens. In conclusion, forest management practices that aim at maintaining different types of dead wood seem to positively affect fungal diversity, but may additionally increase the risk of survival of potential tree pathogens. This potential risk seems to depend on the tree species.
Soil-wood interactions : Influence of decaying coniferous and broadleaf logs on composition of soil fungal communities
Wal, Annemieke van der; klein Gunnewiek, Paulien ; Boer, Wietse de - \ 2017
Fungal Ecology 30 (2017). - ISSN 1754-5048 - p. 132 - 134.
Cord-forming fungi - Illumina MiSeq sequencing of ITS - LOGLIFE - Soil fungal communities - Species richness - Tree species - Wood decomposition - Wood leachates
Wood-inhabiting fungi may affect soil fungal communities directly underneath decaying wood via their exploratory hyphae. In addition, differences in wood leachates between decaying tree species may influence soil fungal communities. We determined the composition of fungi in 4-yr old decaying logs of Larix kaempferi and Quercus rubra as well as in soil directly underneath and next to logs. Fungal community composition in soil covered by logs was different from that in wood and uncovered soil and was clearly influenced by the tree species. Soil fungal species richness under logs was lower than in uncovered soil but higher than in decaying wood. The amount of exploratory hyphae of log-inhabiting fungi was only high close to decaying logs. In conclusion, there is a small but significant effect of decaying coniferous and broadleaf logs on soil fungal communities directly underneath logs, likely affected by differences in wood chemistry and fungal preference between tree species.
Decrease in ionized and total magnesium blood concentrations in endurance athletes following an exercise bout restores within hours-potential consequences for monitoring and supplementation
Terink, Rieneke ; Balvers, Michiel G.J. ; Hopman, Maria T. ; Witkamp, Renger F. ; Mensink, Marco ; Klein Gunnewiek, J.M.T. - \ 2017
International Journal of Sport Nutrition & Exercise Metabolism 27 (2017)3. - ISSN 1526-484X - p. 164 - 170.
Blood analysis - Micronutrients - Status monitoring
Magnesium is essential for optimal sport performance, generating an interest to monitor its status in athletes. However, before measuring magnesium status in blood could become routine, more insight into its diurnal fluctuations and effects of exercise itself is necessary. Therefore, we measured the effect of an acute bout of exercise on ionized (iMg) and total plasma magnesium (tMg) in blood obtained from 18 healthy well-trained endurance athletes (age, 31.1 ± 8.1 yr.; VO2max, 50.9 ± 7.5 ml/kg/min) at multiple time points, and compared this with a resting situation. At both days, 7 blood samples were taken at set time points (8:30 fasted, 11:00, 12:30, 13:30, 15:00, 16:00, 18:30). The control day was included to correct for a putative diurnal fluctuation of magnesium. During the exercise day, athletes performed a 90 min bicycle ergometer test (70% VO2max) between 11:00 and 12:30. Whole blood samples were analyzed for iMg and plasma for tMg concentrations. Both concentrations decreased significantly after exercise (0.52 ± 0.04-0.45 ± 0.03 mmol/L and 0.81 ± 0.07-0.73 ± 0.06 mmol/L, respectively, p <.001) while no significant decline was observed during that time-interval on control days. Both, iMg and tMg, returned to baseline, on average, 2.5 hr after exercise. These findings suggest that timing of blood sampling to analyze Mg status is important. Additional research is needed to establish the recovery time after different types of exercise to come to a general advice regarding the timing of magnesium status assessment in practice.
Priming of soil organic matter : Chemical structure of added compounds is more important than the energy content
Lonardo, D.P. Di; Boer, W. De; Klein Gunnewiek, P.J.A. ; Hannula, S.E. ; Wal, A. van der - \ 2017
Soil Biology and Biochemistry 108 (2017). - ISSN 0038-0717 - p. 41 - 54.
Bacterial and fungal communities - DNA stable isotope probing - Microbial growth - Nitrogen - Priming effect - Soil organic matter
The addition of easily degradable compounds to soil (e.g. root exudates, plant residues) can result in priming effects (PE), a short-term change in the turnover of soil organic matter (SOM). Although PE are recognized to be large enough to be taken into account into the ecosystem carbon balance, the exact mechanisms are still unknown. Here, we examined the effect of two characteristics of added compounds on PE, namely metabolic usable energy for microbes and resemblance to recalcitrant fractions of soil organic matter (SOM). For this purpose, glucose, cellobiose (energy rich compounds, low resemblance with recalcitrant SOM) and vanillic acid (energy-poor compound, higher resemblance with recalcitrant SOM) were selected. In addition the effect of mineral nitrogen (N) on PE was tested. 13C labelled compounds were mixed with sandy soil from an ex-arable site. To separate the effect of energy content from that of resemblance to SOM, the amount of carbon and the amount of energy content of added compounds was kept constant in treatments, respectively. The community structure of microbes that were able to use added compounds was evaluated using stable isotope probing (DNA-SIP) combined with qPCR and Illumina sequencing. When corrected for energy content, vanilic acid induced the highest CO2 respiration and PE. DNA-SIP revealed that bacterial classes like β- and γ-Proteobacteria, that are known to harbour many opportunistic bacteria, responded quickly (5 h) with incorporation of 13C from added substrates, whereas classes like Acidobacteria and Actinobacteria responded over a longer incubation time. In treatments where the energy-level of added compounds was kept constant, vanillic acid caused an increase in DNA copy numbers of bacteria and fungi using native SOM after prolonged incubation. The contribution of fungi to PE was minor, reflecting the low F:B ratio of the soil used for the experiment. Different substrates resulted in different PE but appeared to stimulate the growth of similar bacterial groups. This suggests that the added compounds stimulate different enzyme systems within similar bacterial taxa. Although combined addition of mineral nitrogen (ammonium nitrate) and organic compounds caused a slightly extra increase in PE in most treatments, this might be an artefact as addition of mineral N only decreased respiration. Overall our results indicate that the effect of chemical structure of added compounds on PE is much larger than the effect of energy-content.
Patterns of natural fungal community assembly during initial decay of coniferous and broadleaf tree logs
Wal, Annemieke van der; Klein Gunnewiek, P.J.A. ; Cornelissen, J.H.C. ; Crowther, Thomas W. ; Boer, Wietse de - \ 2016
Ecosphere 7 (2016)7. - ISSN 2150-8925
454 pyrosequencing of ITS - Competitive strength - Endophytic fungi - Fungal interactions - LOGLIFE - Natural fungal community assembly - Priority effects - Succession - Wood decomposition - Wood traits
Community assembly processes do not only influence community structure, but can also affect ecosystem processes. To understand the effect of initial community development on ecosystem processes, we studied natural fungal community dynamics during initial wood decay. We hypothesize that fungal community assembly dynamics are driven by strong priority effects of early-arriving species, which lead to predictable successional patterns and wood decay rates. Alternatively, equivalent colonization success of randomly arriving spores has the potential to drive stochastic community composition and wood decay rates over time. To test these competing hypotheses, we explored the changes in fungal community composition in logs of two tree species (one coniferous and one broadleaf) during the early stages of wood decomposition in a common garden approach. Initial communities were characterized by endophytic fungi, which were highly diverse and variable among logs. Over the first year of decomposition, there was little evidence for priority effects, as early colonizers displaced the endophytic species, and diversity fell as logs were dominated by a few fungal species. During this period, the composition of colonizing fungi was related to the decomposition rates of sapwood. During the second year of decomposition, fungal community composition shifted drastically and the successional dynamics varied considerably between tree species. Variation in fungal community composition among coniferous (Larix kaempferi) logs increased, and there remained no evidence for any priority effects as community composition became stochastic. In contrast, early colonizers still dominated many of the deciduous (Quercus rubra) logs, with a temporally consistent impact on community composition. For both tree species, wood decay rates levelled off and the relationship with fungal community composition disappeared. Our results indicate that priority effects are relatively minimal in naturally occurring fungal community assembly processes. Instead, fungal successional dynamics are governed predominantly by combative abilities of colonizing fungi, and factors that shape fungal communities over time can differ considerably between tree species. Our results indicate that an increased focus of competitive strength among species, rather than priority effects, may be key to predict community assembly and the ecosystem process they provide.
Non-random species loss in bacterial communities reduces antifungal volatile production
Hol, G. ; Garbeva, P. ; Hordijk, C. ; Hundscheid, M.P.J. ; Klein Gunnewiek, P.J.A. ; Agtmaal, M. van; Boer, W. de - \ 2015
Ecology 96 (2015)8. - ISSN 0012-9658 - p. 2042 - 2048.
The contribution of low-abundance microbial species to soil ecosystems is easily overlooked because there is considerable overlap between metabolic abilities (functional redundancy) of dominant and subordinate microbial species. Here we studied how loss of less abundant soil bacteria affected the production of antifungal volatiles, an important factor in the natural control of soil-borne pathogenic fungi. We provide novel empirical evidence that the loss of soil bacterial species leads to a decline in the production of volatiles that suppress root pathogens. By using dilution-to-extinction for seven different soils we created bacterial communities with a decreasing number of species and grew them under carbon-limited conditions. Communities with high bacterial species richness produced volatiles that strongly reduced the hyphal growth of the pathogen Fusarium oxysporum. For most soil origins loss of bacterial species resulted in loss of antifungal volatile production. Analysis of the volatiles revealed that several known antifungal compounds were only produced in the more diverse bacterial communities. Our results suggest that less abundant bacterial species play an important role in antifungal volatile production by soil bacterial communities and, consequently, in the natural suppression of soil-borne pathogens.
Antifungal rhizosphere bacteria can increase as response to the presence of saprotrophic fungi
Boer, W. de; Hundscheid, M.P.J. ; Klein Gunnewiek, P.J.A. ; Ridder-Duine, A.S. De; Thion, C. ; Veen, J.A. van; Wal, Annemieke van der - \ 2015
PLoS ONE 10 (2015)9. - ISSN 1932-6203 - 15 p.
Knowledge on the factors that determine the composition of bacterial communities in the vicinity of roots (rhizosphere) is essential to understand plant-soil interactions. Plant species identity, plant growth stage and soil properties have been indicated as major determinants of rhizosphere bacterial community composition. Here we show that the presence of saprotrophic fungi can be an additional factor steering rhizosphere bacterial community composition and functioning. We studied the impact of presence of two common fungal rhizosphere inhabitants (Mucor hiemalis and Trichoderma harzianum) on the composition of cultivable bacterial communities developing in the rhizosphere of Carex arenaria (sand sedge) in sand microcosms. Identification and phenotypic characterization of bacterial isolates revealed clear shifts in the rhizosphere bacterial community composition by the presence of two fungal strains (M. hiemalis BHB1 and T. harzianum PvdG2), whereas another M. hiemalis strain did not show this effect. Presence of both M. hiemalis BHB1 and T. harzianum PvdG2 resulted in a significant increase of chitinolytic and (in vitro) antifungal bacteria. The latter was most pronounced for M. hiemalis BHB1, an isolate from Carex roots, which stimulated the development of the bacterial genera Achromobacter and Stenotrophomonas. In vitro tests showed that these genera were strongly antagonistic against M. hiemalis but also against the plant-pathogenic fungus Rhizoctonia solani. The most likely explanation for fungal-induced shifts in the composition of rhizosphere bacteria is that bacteria are being selected which are successful in competing with fungi for root exudates. Based on the results we propose that measures increasing saprotrophic fungi in agricultural soils should be explored as an alternative approach to enhance natural biocontrol against soil-borne plant-pathogenic fungi, namely by stimulating indigenous antifungal rhizosphere bacteria.
Recommended intakes of vitamin D to optimise health, associated circulating 25-hydroxyvitamin D concentrations, and dosing regimens to treat deficiency: workshop report and overview of current literature
Balvers, M.G.J. ; Brouwer-Brolsma, E.M. ; Endenburg, S. ; Groot, C.P.G.M. de; Kok, F.J. ; Klein Gunnewiek, J.M.T. - \ 2015
Journal of Nutritional Science 4 (2015). - ISSN 2048-6790 - 8 p.
Vitamin D is a fat-soluble hormone that traditionally has been linked to bone health. Recently, its involvement has been extended to other (extra-skeletal) disease areas, such as cancer, CVD, energy metabolism and autoimmune diseases. Vitamin D deficiency is a worldwide problem, and several recommendation-setting bodies have published guidelines for adequate vitamin D intake and status. However, recommendations from, for example, the Health Council of the Netherlands do not provide advice on how to treat vitamin D deficiency, a condition that is often encountered in the clinic. In addition, these recommendations provide guidelines for the maintenance of ‘minimum levels’, and do not advise on ‘optimum levels’ of vitamin D intake/status to further improve health. The NutriProfiel project, a collaboration between the Gelderse Vallei Hospital (Ede, the Netherlands) and the Division of Human Nutrition of Wageningen University (Wageningen, the Netherlands), was initiated to formulate a protocol for the treatment of vitamin deficiency and for the maintenance of optimal vitamin D status. To discuss the controversies around treatment of deficiency and optimal vitamin D status and intakes, a workshop meeting was organised with clinicians, scientists and dietitians. In addition, a literature review was conducted to collect recent information on optimal intake of vitamins, their optimal circulating concentrations, and effective dosing regimens to treat deficiency. This information has been translated into the NutriProfiel advice, which is outlined in this article.
Evaluatie van de voedingsstatus van Nederlandse patiënten met chronische inflammatoire darmziekten : een pilotonderzoek
Berg, M.C. van den; Plas, M. ; Mares, W. ; Witteman, B.J.M. ; Klein Gunnewiek, J.M.T. ; Vries, J.H.M. de - \ 2014
Nederlands Tijdschrift voor Voeding en Dietetiek 60 (2014)1. - ISSN 1875-9955 - p. S1 - S12.
voedingstoestand - darmziekten - chronische darmontstekingen - ondervoeding - patiënten - voeding en gezondheid - nutritional state - intestinal diseases - inflammatory bowel diseases - undernutrition - patients - nutrition and health
Introductie Het doel van deze pilotstudie was het verkrijgen van inzicht in de voedingsstatus van Nederlandse patiënten met chronische inflammatoire darmziekten (IBD). Methoden De voedingsstatus werd onderzocht op basis van MUST-score, handknijpkracht, micronutriëntstatus in het bloed en voedingsinname. Daarnaast werden leeftijd, geslacht, ziektebeeld, ziekteactiviteit, kwaliteit van leven en medicatiegebruik geïnventariseerd en gecorreleerd aan ziekteactiviteit. Resultaten 41 personen met IBD (17 mannen en 24 vrouwen, 19-74 jaar), onder wie 22 met colitis ulcerosa en 19 met de ziekte van Crohn, namen deel aan het onderzoek. 4 deelnemers hadden volgens de MUST-score een verhoogd risico op ondervoeding. Van 4 deelnemers was de handknijpkracht onder de referentiewaarde. 14 personen hadden een tekort aan vitamine D, 3 aan selenium, 3 aan foliumzuur, 1 aan vitamine B12 en 1 aan magnesium. De micronutriëntconcentraties verschilden niet tussen deelnemers met verschillende ziektebeelden, MUST-scores of handknijpkracht. Serum vitamine B1 verschilde als enige micronutriënt tussen mannen en vrouwen (p=0,047). Foliumzuurconcentraties waren hoger bij hogere ziekteactiviteit (p=0,022) en bij lagere kwaliteit van leven (p=0,030). Serumspiegels van vitamine D en vitamine E waren hoger voor deelnemers boven de leeftijdsmediaan dan voor deelnemers daaronder (50 jaar, respectievelijk: p
|CO2 fluxes from arable organic soils in Sweden.
Weslien, P. ; Walden, J. ; Jensen, N.O. ; Kasimir Klemedtsson, U. ; Klein Gunnewiek, H.J.T. ; Leffelaar, P.A. ; Goudriaan, J. ; Berglund, K. ; Klemendtsson, L. - \ 1998
|Modelling greenhouse gas emissions from farmed organic soils.
Leffelaar, P.A. ; Goudriaan, J. ; Klein Gunnewiek, H.J.T. - \ 1998
|Biodiversiteit en stabiliteit van complexe bodemecosystemen
Ruiter, P.C. de; Neutel, A.M. ; Klein Gunnewiek, H.J. ; Moore, J.C. - \ 1995
In: Biodiversiteit, een natuurlijke hulpbron in de landbouw; de betekenis voor het landbouw- en milieu-onderwijs / van Eldik, A., van Haarlem, R., - p. 8 - 13.
|Modelling N2O emission from (grazed) grassland
Bril, J. ; Faassen, H.G. van; Klein Gunnewiek, H. - \ 1995
Unknown Publisher - 45 p.
|Modelling the emission of dinitrogen oxide from mown and from grazed grassland
Bril, J. ; Faassen, H.G. van; Klein Gunnewiek, H. - \ 1995
In: Climate change research: evaluation and policy implications / Zwerver, S., van Rompaey, R.S.A.R., Kok, M.J.T., Berk, M.M., Amsterdam : Elsevier Science - p. 631 - 634.