39 research outputs found
Vitamin D: beyond bone.
In recent years, vitamin D has been received increased attention due to the resurgence of vitamin D deficiency and rickets in developed countries and the identification of extraskeletal effects of vitamin D, suggesting unexpected benefits of vitamin D in health and disease, beyond bone health. The possibility of extraskeletal effects of vitamin D was first noted with the discovery of the vitamin D receptor (VDR) in tissues and cells that are not involved in maintaining mineral homeostasis and bone health, including skin, placenta, pancreas, breast, prostate and colon cancer cells, and activated T cells. However, the biological significance of the expression of the VDR in different tissues is not fully understood, and the role of vitamin D in extraskeletal health has been a matter of debate. This report summarizes recent research on the roles for vitamin D in cancer, immunity and autoimmune diseases, cardiovascular and respiratory health, pregnancy, obesity, erythropoiesis, diabetes, muscle function, and aging
Vitamin D Status and Vitamin D-Dependent Apoptosis in Obesity
The role of vitamin D in obesity appears to be linked to vitamin D insufficient/deficient status. However, mechanistic understanding of the role of vitamin D in obesity is lacking. We have shown earlier that the vitamin D hormonal form, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), induces cell death by apoptosis in mature adipocytes. This effect of the hormone is mediated by the cellular Ca2+ signaling pathway: a sustained increase of intracellular (cytosolic) Ca2+ concentration followed by activation of Ca2+-dependent initiators and effectors of apoptosis. In recent animal studies, we demonstrated that low vitamin D status is observed in diet-induced obesity (DIO). High intake of vitamin D3 in DIO decreased the weight of white adipose tissue and improved biomarkers related to adiposity and Ca2+ regulation. The anti-obesity effect of vitamin D (1,25(OH)2D3) in DIO was determined by the induction of Ca2+-mediated apoptosis in mature adipocytes executed by Ca2+-dependent apoptotic proteases (calpains and caspases). Thus, a high intake of vitamin D in obesity increases vitamin D nutritional status and normalizes vitamin D hormonal status that is accompanied by the reduction of adiposity. Overall, our findings imply that vitamin D may contribute to the prevention of obesity and obesity-related diseases and that the mechanism of the anti-obesity effect of 1,25(OH)2D3 includes induction of Ca2+-mediated apoptosis in adipocytes
Vitamin D and COVID-19: How Much Vitamin D Does a Man Need?
A number of observational studies and reviews on the potential role of vitamin D in COVID-19 have been published since the beginning of this ongoing global pandemic [...
Trace-Element Analysis by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS): a Case Study for Agates from Nowy Kościoł, Poland
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was applied to detect
trace elements in agate from Permian volcanics (Nowy Kościoł, Poland) in low concentrations and
with high spatial resolution. The used LA-ICP-MS system consists of a DUV 193 laser ablation system
linked to a Thermo Finnigan Element 2 mass spectrometer. The use of a 193 nm ArF excimer laser
(50-200 mJ energy output) and the standards NIST 611 and NIST 612 enables to produce and analyse
small crater diameters down to 5 μm.
Trace-element profiles have been analyzed for the elements Ti, Ge, Al, Fe, Mn, U, Th, Ba, Sr, Rb, Cs,
and Y in the ppm- and sub-ppm level. The concentrations of the REE are sometimes below the detection
limit of the method. Almost all elements (except Cu) display higher contents in chalcedony than in the
macrocrystalline quartz. Fe, for instance, shows a 100 times higher concentration in agate bands
compared to quartz, which may be due to finely distributed iron oxide particles in the chalcedony
which probably act as colour pigments.
The trace elements in agate are released simultaneously with Si during alteration of the surrounding
volcanic rocks. Oxygen isotope data indicate that silica accumulation and agate formation took place
at temperatures below 120°C. The characteristic trace-element distribution patterns in agate result
from a self-purification process during crystallization of chalcedony and quartz from a silica gel
Towards DNA sensing polymers: interaction between acrylamide/3-(N,N-dimethylaminopropyl)-acrylamide and DNA phage λ at various N/P ratios
The present study strongly relates to ongoing research on the development of cationic polymers which are
of great interest due to their enormous potential for biomedical applications, especially as non-viral vectors
for gene therapy, antimicrobial agents and active components in DNA sensing devices. The current paper
demonstrates that a functional group approach can be successfully realized in a free-radical
copolymerization process to prepare cationic copolymers with a desired composition of amine groups,
which can be protonated in water thus, providing electrostatic interactions between a polycation and
DNA. Three replicas of the cationic copolymer, acrylamide/3-(N,N-dimethylaminopropyl)-acrylamide
(AADMAPA), were synthesized using this strategy. The values of average molecular mass and
polydispersity index, are similar for the replicas, averaged to 24 000 2000 g mol1 and 1.5 0.1,
respectively. The copolymer composition according to 1
H-NMR (D2O), was corresponded to the molar
ratio of initial monomers. The dynamic light scattering studies and zeta potential measurements
confirmed that in water positively charged AADMAPA/DNA polyplexes are formed at N/P > 2.2: the
formed particles have bimodal distributions with the average diameters of 70 and 700 nm. Zeta potential
measurements indicated that the point of zero charge (isoelectric point) is close to N/P y 2.2.
According to the atomic force microscopy positively charged AADMAPA/DNA polyplexes have axially
symmetric shapes.The authors are grateful to Prof. Babushkina T. A., Mrs Klimova
T. P. for helpful discussion and NMR spectral data. The authors
also acknowledge Mrs Klemenkova Z. S. for IR spectral data. E.
Laukhina acknowledges the support from Instituto de Salud
Carlos III, through “Acciones CIBER”. The Networking Research
Center on Bioengineering, Biomaterials and Nanomedicine
(CIBER-BBN), an initiative funded by the VI National R&D&I
Plan 2008-2011, Iniciativa Ingenio 2010.Peer reviewe