Practical guidelines for the supplementation of vitamin D and the treatment of deficits in Central Europe — recommended vitamin D intakes in the general population and groups at risk of vitamin D deficiency

Wstęp: Wyniki badań z ostatnich lat dokumentują wiele korzyści wynikających z działania witaminy D na organizm człowieka na wszystkichetapach jego życia. Większość badań epidemiologicznych sugeruje, że niedobór witaminy D jest powszechny wśród mieszkańców EuropyŚrodkowej. Naturalną konsekwencją tej sytuacji jest konieczność ciągłego uświadamiania społeczeństwu oraz środowisku medycznemu,jaką rolę odgrywa witamina D w rozwoju i funkcjonowaniu organizmu ludzkiego.Metody: Na podstawie przeglądu danych literaturowych Polski Zespół Wielodyscyplinarny opracował tezy dotyczące zasad suplementacjiwitaminą D, które przesłano do członków Komitetu Naukowego konferencji „Witamina D — minimum, maksimum, optimum”,19–20 Październik, 2012, Warszawa. W trakcie powyższej konferencji z udziałem 550 delegatów oraz Ekspertów różnych dziedzin medycynyomówiono i przedyskutowano propozycje wytycznych suplementacji witaminą D populacji Europy Środkowej.Wyniki: W efekcie przeprowadzonych dyskusji Zespół Ekspertów opracował wytyczne suplementacji witaminą D dla wszystkich grupwiekowych populacji Europy Środkowej. Określono również kryteria diagnostyczne charakteryzujące stan zaopatrzenia organizmu w witaminę D: deficyt witaminy D ustalono jako stężenie 25(OH)D < 20 ng/mL (< 50 nmol/L)], suboptymalne zaopatrzenie jako stężenie25(OH)D wynoszące 20–30 ng/mL (50–75 nmol/L), a stężenie 30–50 ng/mL (75–125 nmol/L) uznano za docelowe dla zapewnienia efektuplejotropowego witaminy D.Wnioski: Poprawa obecnego stanu zaopatrzenia witaminy D w grupach dzieci, młodzieży, osób aktywnych zawodowo i seniorówpowinna zostać włączona do priorytetów polityki zdrowotnej społeczeństw Europy Środkowej.Introduction: Adequate Vitamin D intake and its concentration in serum are important for bone health and calcium–phosphate metabolismas well as for optimal function of many organs and tissues. Documented trends in lifestyle, nutritional habits and physical activityappear to be associated with moderate or severe Vitamin D deficits resulting in health problems. Most epidemiological studies suggest thatVitamin D deficiency is prevalent among Central European populations. Concern about this problem led to the organising of a conferencefocused on overcoming Vitamin D deficiency.Methods: After reviewing the epidemiological evidence and relevant literature, a Polish multidisciplinary group formulated theses onrecommendations for Vitamin D screening and supplementation in the general population. These theses were subsequently sent to ScientificCommittee members of the ‘Vitamin D — minimum, maximum, optimum’ conference for evaluation based on a ten-point scale.With 550 international attendees, the meeting ‘Vitamin D — minimum, maximum, optimum’ was held on October 19–20, 2012 in Warsaw(Poland). Most recent scientific evidence of both skeletal and non-skeletal effects of Vitamin D as well as the results of panellists’ votingwere reviewed and discussed during eight plenary sessions and two workshops.Results: Based on many polemical discussions, including post-conference networking, the key opinion leaders established ranges ofserum 25-hydroxyVitamin D concentration indicating Vitamin D deficiency [< 20 ng/mL (< 50 nmol/L)], suboptimal status [20–30 ng/mL(50–75 nmol/L)], and target concentration for optimal Vitamin D effects [30–50 ng/mL (75–125 nmol/L)]. General practical guidelines regardingsupplementation and updated recommendations for prophylactic Vitamin D intakes in Central European neonates, infants, childrenand adolescents as well as in adults (including recommendations for pregnant and breastfeeding women and the elderly) were developed.Conclusions: Improving the Vitamin D status of children, adolescents, adults and the elderly must be included in the priorities of physicians,healthcare professionals and healthcare regulating bodies. The present paper offers elaborated consensus on supplementationguidance and population strategies for Vitamin D in Central Europe

The Longitudinal Superdiffusive Motion of Block Copolymer in a Tight Nanopore

The structure and dynamic properties of polymer chains in a confined environment were studied by means of the Monte Carlo method. The studied chains were represented by coarse-grained models and embedded into a simple 3D cubic lattice. The chains stood for two-block linear copolymers of different energy of bead–bead interactions. Their behavior was studied in a nanotube formed by four impenetrable surfaces. The long-time unidirectional motion of the chain in the tight nanopore was found to be correlated with the orientation of both parts of the copolymer along the length of the nanopore. A possible mechanism of the anomalous diffusion was proposed on the basis of thermodynamics of the system, more precisely on the free energy barrier of the swapping of positions of both parts of the chain and the impulse of temporary forces induced by variation of the chain conformation. The mean bead and the mass center autocorrelation functions were examined. While the former function behaves classically, the latter indicates the period of time of superdiffusive motion similar to the ballistic motion with the autocorrelation function scaling with the exponent t5/3. A distribution of periods of time of chain diffusion between swapping events was found and discussed. The influence of the nanotube width and the chain length on the polymer diffusivity was studied

Determination of the Parameters of Langmuir-Type Isotherms by the Frontal Analysis Method. Some Identification Aspects

The applicability of the classical frontal analysis method for the estimation of the parameters of various Langmuirian-type adsorption isotherms was examined. Elution profiles corresponding to several adsorption models were simulated using the equilibrium/dispersive model of chromatography. A noise sequence was added to the calculated profiles to simulate the detector error, following which the isotherm parameters were derived back from the generated chromatograms. The uncertainty of the estimates is discussed critically in terms of the standard deviations from the mean and real values of the parameters

Droplet on a regularly patterned solid. Wenzel’s regime and meso-scale roughness

The applicability of Wenzel’s equation to describe a liquid droplet settled on the solid surface regularly patterned with rectangular prisms was examined by means of simulations of the droplet/surface system morphology and energetics. The droplet deposited on the meso-scale surface roughness (i.e. the droplet size was larger than the size of heterogeneities by about an order of magnitude) was considered. Several different approaches to the estimation of the contact angle were employed. The discrepancies between the results of simulated experimental measurements and the predictions based on the Wenzel equation were analyzed and discussed. The influence of three-phase contact line effects on the droplet morphology and the existence of metastable states was shown

Conformational entropy of a polymer chain grafted to rough surfaces

A polymer molecule (represented by a statistical chain) end-grafted to a topologically rough surface was studied by static MC simulations. A modified self-avoiding walk on a cubic lattice was used to model the polymer in an athermal solution. Different statistical models of surface roughness were applied. Conformational entropies of chains attached to uncorrelated Gaussian, Brownian, and fractional Brownian surfaces were calculated. Results were compared with the predictions of a simple analytical model of a macromolecule end-grafted to a fractal surface. [Figure: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00894-012-1546-5) contains supplementary material, which is available to authorized users