454 research outputs found
Polymer brush-coatings to prevent biomaterials associated infection:initial bacterial adhesion and biofilm formation
Polymer brush-coatings to prevent biomaterials associated infection:initial bacterial adhesion and biofilm formation
Развитие научных основ новых методов интенсификации процессов тепломассообмена в рабочих средах воздействием силовых полей периодической интенсивности
Проведено оглядовий аналіз результатів досліджень, виконаних у відділі високотемпературної теплотехніки ІГТМ НАНУ з впливу вібраційних полів на тепломассоперенос в рідких робочих середовищах у великому об'ємі, каналах і пористих структурах.Results of research performed in the department of high-temperature heat engineering of IGTM NAS of Ukraine on the effect of vibration on the heat and mass transfer in liquid working media, in a large volume in channels and in porous structures are reviewed
Formulation, Delivery and Stability of Bone Morphogenetic Proteins for Effective Bone Regeneration
Drug Delivery Technolog
Vitamin D status of 6- to 7-year-old children living in Isfahan, Iran
Wstęp: Witamina D ma podstawowe znaczenie dla utrzymania dobrego zdrowia. O niedoborach witaminy D donoszą autorzy z wielu
krajów, również tych o dużym stopniu nasłonecznienia. Niniejsze badanie przeprowadzono w celu dokonania oceny stężenia witaminy
D u zdrowych dzieci w wieku 6-7 lat, zamieszkałych w Isfahanie, Iran.
Materiał i metody: Do badania włączono 513 zdrowych dzieci. Zmierzono u nich stężenie PTH i 25-hydroksywitaminy D (25-OHD)
w surowicy. Określono spożycie witaminy D w diecie, czas ekspozycji na słońce w ciągu doby i odsetek powierzchni ciała wystawionej na
działanie słońca. Przyjęto, że stężenia 25-OHD wynoszące < 20 ng/ml i 10 ng/ml odpowiadają odpowiednio łagodnemu i ciężkiemu
niedoborowi witaminy D. Do ustalenia lokalnych punktów odcięcia dla niedoborów witaminy D użyto krzywych ROC.
Wyniki: U 3% dzieci stężenie witaminy 25-OHD wynosiło < 20 ng/ml, a u 26% wynosiło < 33 ng/ml (lokalny punkt odcięcia dla niedoboru
witaminy D). Czas ekspozycji na słońce i dzienne spożycie witaminy D w diecie miały istotny wpływ na stężenie witaminy D
w surowicy.
Wnioski: W omawianym badaniu wykazano częste występowanie niedoboru witaminy D u dzieci zamieszkałych w Isfahanie. Wydłużenie
czasu ekspozycji na słońce i zwiększenie dziennego spożycia witaminy D w diecie może zapobiec niedoborom witaminy D u tych dzieci.
(Endokrynol Pol 2010; 61 (4): 377-382)Introduction: Vitamin D is essential for the maintenance of good health, and vitamin D deficiency has been reported from many countries,
including those with a lot of sunshine. This study was conducted to evaluate the vitamin D status in healthy 6- to 7-year-old children
in Isfahan, Iran.
Material and methods: Five hundred and thirteen healthy children were enrolled. Serum PTH and 25-hydroxyvitamin D (25-OHD) were
measured. Dietary vitamin D intake, duration of daily sunlight exposure, and percentage of exposed body surface area were determined.
25-OHD levels < 20 ng/mL and < 10 ng/mL were defined as mild and severe vitamin D deficiency, respectively. The ROC curve was
utilized to obtain a local cut-off point of vitamin D deficiency.
Results: 25-OHD was < 20 ng/mL in 3% and < 33 ng/mL (local cut-off point of vitamin D deficiency) in 26% of subjects. Duration of
sunlight exposure and daily intake of vitamin D had significant effects on serum level of vitamin D.
Conclusions: A high prevalence of vitamin D deficiency in Isfahan children was observed in this study. Improvements in duration of
sunlight exposure and daily intake of vitamin D can prevent vitamin D deficiency in these children.
(Pol J Endocrinol 2010; 61 (4): 377-382
Label-Free, Flow-Imaging Methods for Determination of Cell Concentration and Viability
To investigate the potential of two flow imaging microscopy (FIM) techniques (Micro-Flow Imaging (MFI) and FlowCAM) to determine total cell concentration and cell viability.
B-lineage acute lymphoblastic leukemia (B-ALL) cells of 2 different donors were exposed to ambient conditions. Samples were taken at different days and measured with MFI, FlowCAM, hemocytometry and automated cell counting. Dead and live cells from a fresh B-ALL cell suspension were fractionated by flow cytometry in order to derive software filters based on morphological parameters of separate cell populations with MFI and FlowCAM. The filter sets were used to assess cell viability in the measured samples.
All techniques gave fairly similar cell concentration values over the whole incubation period. MFI showed to be superior with respect to precision, whereas FlowCAM provided particle images with a higher resolution. Moreover, both FIM methods were able to provide similar results for cell viability as the conventional methods (hemocytometry and automated cell counting).
FIM-based methods may be advantageous over conventional cell methods for determining total cell concentration and cell viability, as FIM measures much larger sample volumes, does not require labeling, is less laborious and provides images of individual cells.
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CONCLUSIONDrug Delivery Technolog
Improved approach for chondrogenic differentiation of human induced pluripotent stem cells
Human induced pluripotent stem cells (hiPSCs) have demonstrated great potential for hyaline cartilage regeneration. However, current approaches for chondrogenic differentiation of hiPSCs are complicated and inefficient primarily due to intermediate embryoid body formation, which is required to generate endodermal, ectodermal, and mesodermal cell lineages. We report a new, straightforward and highly efficient approach for chondrogenic differentiation of hiPSCs, which avoids embryoid body formation. We differentiated hiPSCs directly into mesenchymal stem /stromal cells (MSC) and chondrocytes. hiPSC-MSC-derived chondrocytes showed significantly increased Col2A1, GAG, and SOX9 gene expression compared to hiPSC-MSCs. Following transplantation of hiPSC-MSC and hiPSC-MSC-derived chondrocytes into osteochondral defects of arthritic joints of athymic rats, magnetic resonance imaging studies showed gradual engraftment, and histological correlations demonstrated hyaline cartilage matrix production. Results present an efficient and clinically translatable approach for cartilage tissue regeneration via patient-derived hiPSCs, which could improve cartilage regeneration outcomes in arthritic joints
Intradermal vaccination with hollow microneedles: a comparative study of various protein antigen and adjuvant encapsulated nanoparticles
Towards the development of a supercritical carbon dioxide spray process to coat solid protein particles
The aim of this study was to develop a supercritical carbon dioxide (scCO2) spray process to coat solid protein particles with a hydrophilic polymer. The final purpose is to manufacture drug particles exhibiting controlled release behaviour in patients. Lysozyme microparticles (about 20 μm) were suspended in a vessel into which a dextran sulphate (DS) solution was dispersed by scCO2 via a nozzle. Upon interaction with the droplets, DS was deposited onto or mixed with suspended lysozyme particles. Particles of about 100 μm were obtained. The zeta-potential analysis and elemental analysis indicated that the top layer of the particles consisted of both lysozyme and DS. Some of the produced particulate materials showed retarded lysozyme release when exposed to water or phosphate buffered saline, holding promise for future production of controlled drug delivery systems for therapeutic proteins.Drug Delivery TechnologyBiopharmaceutic
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