Synthetic oxygen carriers in cardiac tissue engineering

The prominence of cardiovascular diseases has prompted investigations into alternative treatment options, including tissue engineering. Currently, the biggest limitation in cardiac tissue engineering lies in delivering oxygen to all cells within the construct. Synthetic oxygen carriers hold much promise in that they have high affinity for oxygen and can be supplemented to culture medium without adverse effect on the cells. This review highlights two complementary studies by our group that utilized oxygen carriers in cardiac tissue engineering. Experimental and modeling studies were performed to evaluate the effect of a perfluorocarbon (PFC)-based synthetic oxygen carrier, Oxygent, on oxygen supply within tissue engineered cardiac constructs. Porous biorubber scaffolds with an array of parallel channels mimicking the capillary network were seeded with cardiomyocytes and fibroblasts, and cultivated in medium supplemented with PFC. The presence of PFC enhanced the transport of oxygen, increased oxygen concentrations, and yielded constructs that displayed stronger cardiac-like phenotype.     

Obtaining patient-specific point model of the human ilium bone in the case of incomplete volumetric data using the method of parametric regions

In this paper, we present the methodology for determining the point model of the ilium bone in cases when volumetric data of the whole bone are not available. An extreme traumatic bone damage, osteoporosis, destruction of bone tissue by malignant bone tumors or the existence of only 2D medical image (X-ray) can be the reason for the lack of complete volumetric data. Points on the bone surface were defined at the curves that run through 26 previously defined parameters, at the edges of anteroposterior (A–P) and lateral projections and at the parts of the surface between some parameters. Those parts of the surface, enclosed by parameters, represent ten parametric regions. The values of coordinates, which represent the input data in the statistical program, were measured in a uniquely defined coordinate system. After establishing the correlations between the values of coordinates, 8869 different linear and nonlinear regression models were obtained. The prediction values for point coordinates were calculated and exported to a CAD program. Results obtained were tested on a randomly chosen male right ilium bone, applying the methodology for creating the prediction model using the method of parametric regions, which allows creating a complete polygonal model, for each region separately or just for some parts of the region. Results obtained in the form of regression equations for the right ilium bone can be applied to the left ilium bone. The results of the research were verified using a comparative deviation and distance analysis between the initial and obtained polygonal models.     

Immunoglobulins from sera of antiphospholipid syndrome patients are internalized in the HTR-8/SVneo cell line and cytotrophoblast in culture

Women with antiphospholipid syndrome (APS) experience pregnancy complications mostly due to impaired trophoblast cell functions. Antiphospholipid antibodies (aPL) affect extravillous trophoblast in vivo and in culture, but the mechanisms are still poorly understood. Previously, syncytiotrophoblast was shown to bind and internalize aPL, which was not replicated for extravillous cytotrophoblast in short term culture. Here, aPL binding and time dependent internalization was demonstrated with exposure to aPL in the extravillous cell line HTR-8/SVneo and isolated first trimester of pregnancy cytotrophoblast (CT) using immunocytochemistry and flow cytometry. Intracellular aPL were detectable from 2?h of culture, reaching 30.7?±?3.1% (p?<?0.001) positive cells in CT and 24.8?±?7% (p?<?0.01) in HTR-8/SVneo cells at 24?h and 33?±?4.2% (p?<?0.01) at 48?h. The data presented show that extravillous trophoblast cells internalize aPL in a time-dependent manner significantly more than control immunoglobulins after 24?h of exposure.     

Generation of a poor prognostic chronic lymphocytic leukemia-like disease model: PKCα subversion induces up-regulation of PKCβII expression in B lymphocytes

Overwhelming evidence identifies the microenvironment as a critical factor in the development and progression of chronic lymphocytic leukemia, underlining the importance of developing suitable translational models to study the pathogenesis of the disease. We previously established that stable expression of kinase dead protein kinase C alpha in hematopoietic progenitor cells resulted in the development of a chronic lymphocytic leukemia-like disease in mice. Here we demonstrate that this chronic lymphocytic leukemia model resembles the more aggressive subset of chronic lymphocytic leukemia, expressing predominantly unmutated immunoglobulin heavy chain genes, with upregulated tyrosine kinase ZAP-70 expression and elevated ERK-MAPK-mTor signaling, resulting in enhanced proliferation and increased tumor load in lymphoid organs. Reduced function of PKCα leads to an up-regulation of PKCβII expression, which is also associated with a poor prognostic subset of human chronic lymphocytic leukemia samples. Treatment of chronic lymphocytic leukemia-like cells with the selective PKCβ inhibitor enzastaurin caused cell cycle arrest and apoptosis both in vitro and in vivo, and a reduction in the leukemic burden in vivo. These results demonstrate the importance of PKCβII in chronic lymphocytic leukemia-like disease progression and suggest a role for PKCα subversion in creating permissive conditions for leukemogenesis.     

New protic ionic liquids for fungi and bacteria removal from paper heritage artefacts

In this work, new protic ionic liquids (PILs) with 1-ammonium-2-propanol cation and nine different anions: formate (For), acetate (Ac), lactate (Lac), trifluoroacetate (TFA), chloroacetate (ClA), trichloroacetate (TClA), 3-chloropropionate (3-ClP), 4-chlorobutyrate (4-ClB) and mandelate (Man) were prepared in order to study their antimicrobial activity and possible application for fungi and bacteria removal from deteriorated paper heritage. Ten filamentous fungal strains isolated from specific pigmented area of the damaged books: Trichoderma sp., Cladosporium sp., Penicillium sp.⁽¹⁻³⁾, Penicillium citrinum, Aspergillus sp.^(1,2), Aspergillus flavus, Fusarium graminearum, eight Gram positive and Gram negative ATCC bacterial strains: B. subtilis⁽⁶⁶³³⁾, S. aureus⁽⁶⁵³⁸⁾, E. faecalis^(19433), K. rhizophila⁽⁹³⁴¹⁾, E. coli^(11229), S. enteritidis^(13076), P. mirabilis^(12453), P. aeruginosa^(15692) and two yeast Candida strains: Candida albicans^{(ATCC 10231)} and Candida albicans^(L) were used in this study. The results indicated that antimicrobial activity of selected ionic liquids is significantly affected by the size and specific functional groups in the anion structure. These facts opened the possibility for molecular design of new ionic liquids with strong inhibition properties against the specific bacterial, mould and yeast strains. The significant antimicrobial properties observed in this research suggest that studied PILs may have potential applications in the paper art and artefact cleaning and conservation replacing thus, conventional solvents and organic substances that are toxic for humans and environment.

New protic ionic liquids with 1-ammonium-2-propanol cation and nine different anions were prepared in order to study their antimicrobial activity and possible application for fungi and bacteria removal from deteriorated paper heritage.     

Factor V in an Industrial Population

S ummary . Factor-V levels have been measured in a random sample of 626 men and 307 women working in a variety of occupations in North West London. The method is an automated one-stage assay using the same batch of freeze-dried thromboplastin, all results being expressed in terms of the same freeze-dried standard plasma; it has been shown that only one dilution of test plasma is necessary. Factor-V levels are significantly higher when venepuncture is difficult than when it is satisfactory, the mean levels being about 130% and 117% respectively. Factor-V levels are approximately normally distributed; they are similar in men and women and in blacks and whites, and increase significantly with age at the rate of about 0.6% per annum. Factor-V levels are not affected by oral contraceptives or the menopause, and there are no differences according to blood group or secretor status.