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Impact of solute exchange between erythrocytes and plasma on hemodialyzer clearance

Waniewski J., Poleszczuk J., Pietribiasi M., Debowska M., Wojcik-Zaluska A., Zaluska W.

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 1

265--276

EN

The standard theory of mass transport in dialyzer for water solutions was extended for solutes distributed in both plasma (PW) and erythrocyte intracellular (EW) water. Blood flow was divided into two separate flows of PW and EW with the diffusive exchange of solutes across cellular membrane (CM). Diffusive permeability of CM for urea and creatinine were assumed according to literature data. Computer simulations based on partial differential equations demonstrated that urea diffuses fast across CM and can be approximately considered as distributed uniformly in both blood flow components. In contrast, creatinine can be considered as distributed only in PW flow during the passage along the dialyzer. Therefore, the traditional formula for dialyzer clearance can be applied for urea and creatinine with the adjustment of their effective ‘‘blood’’ flow, but not for solutes with intermediate molecular mass. In vivo clearances of urea and creatinine were, as expected, lower than the respective theoretical predictions based of the diffusive permeability, P, times membrane surface area, A, parameters, PA, for dialyzer membrane, estimated for water solutions, by 33.6 ± 10.9% for creatinine and 10.8 ± 9.4% for urea. The estimated in vivo PAs were for creatinine 65.4 ± 26.0% and for urea 32.0 ± 10.9% lower than in vitro values provided by manufacturers. The much higher drop in clinical clearance/PA for creatinine than for urea suggests that the exchange of creatinine between plasma and dialysis fluid needs to be adjusted for the reduction of the dialyzer membrane surface area, which is effectively available for creatinine, caused by the presence of erythrocytes.

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Ślady krwi na Całunie Turyńskim : analiza materiałowa od mikro do nanoskali

Jaworski J. S.

Wiadomości Chemiczne

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2018

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[Z] 72, 1-2

61--80

EN

Modern experimental methods of materials science including optical and electron microscopy (SEM, ESEM, HRTEM), X-ray spectroscopy (EDX, WAXS), Raman and FTIR spectroscopy used in investigations of structures of new materials can be also successfully applied for analysis of archeological, cultural heritage and art objects. An interesting example of such analyses are investigations of microscopic fibers and particles taken previously from areas attributed to the blood on the Shroud of Turin. Detailed analyses performed by a number of research groups published in 2015–2017 are reviewed. They confirmed previous hypothesis on blood authenticity and discovered new evidences indicated a violence hidden behind the death. In particular, the presence of old red blood cells was documented by Lucotte [20], of bile pigment biliverdin by Laude and Fanti [28], of iron oxide cores of ferritin bounded to nanoparticles of creatinine by Carlino et al. [31]. The last result is typical for patients with severe polytrauma indicating at the unexpected nonoscopic level a tremendous suffering of the victim wrapped in the Shroud of Turin. Bigger particles of mineral pigments: ochre (iron oxide) and vermillion (mercury sulfide) were also found but they can be easily distinguished form blood particles using environmental electron microscopy ESEM with the back-scattered electrons detector [24]. The statistical analysis of a sample composition made by Fanti and Zagotto [24] indicated that 90–95% of the observed volume corresponds to the blood and only remainder represents inorganic pigments. Thus, it was proposed [24] that the original human blood on Shroud stains was much later reinforced by red pigments using a color dust without any binder and this hypothesis can easily explain controversies between previous results of different researches.

3

Different Complexation Behavior of a Proton Transfer Compound Obtained from Pyridine-2,6-dicarboxylic Acid and Creatinine with Tl(I), Cu(II), Fe(III) and Bi(III): Synthesis, Characterization, Crystal Structures and Solution Studies

Aghabozorg H., Ramezanipour F., Soleimannejad J., Sharif M. A., Shokrollahi A., Shamsipur M., Moghimi A., Attar Gharamaleki J., Lippolis V., Blake A. J.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 3

487-507

EN

The different complexation methods of a proton transfer compound, (creatH)(pydcH)źH2O (pydcH2 = pyridine-2,6-di carboxylic acid; creat = creatinine) with metal ions have been studied and formation of [(Tl(pydcH)]n (1), [(Fe(pydc)(H2O)2)2ox]ź6H2O (2), [Cu(pydc)(pydcH2)]ź2H2O (3) and (creatH)2[Bi(pydc)2]2ź4H2O (4) are re ported. The characterization was performed using IR spectroscopy and single crystal X-ray diffraction analysis. The Tl(I) complex [(Tl(pydcH)]n (1) obtained from (creatH)(pydcH)źH2O is a polymeric system, showing only the contribution of the anionic species of (creatH)(pydcH)źH2O to the complexation. The Fe(III) and the Cu(II) complexes [(Fe(pydc)(H2O)2)2ox]ź6H2O (2) (ox = ox a late) and [Cu(pydc)(pydcH2)]ź2H2O (3) were also obtained from (creatH)(pydcH)źH2O. The Bi(III) complex (creatH)2[Bi(pydc)2]2ź4H2O (4) is a dimeric system, showing both contribution of the cationic and anionic fragments. The complexes 1-4 show a variety of structural features including mononuclear, binuclear, polymeric structures and unusual ligand formation. In compounds (1), (2), (3) and (4), a large number of hydrogen bonds are observed. These interactions as well as p-p stacking play an important role in the formation and stabilization of supra molecular systems in the crystal lattices. The stoichiometry and stability of the Cu(II), Tl(I) and Bi(III) complexes with (pydc)(creat) and Fe(III) with pydc-ox mixture in aqueous solution were investigated by potentiometric pH titration.

4

Creatinine and Creatininium Cation in Water Solution. Tautomerism and Quantitative Interpretation of the Solution Acidity Effect on 1H, 13C and 14 N NMR Chemical Shifts

Kotsyubynskyy D., Molchanov S., Gryff-Keller A.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 2

239-248

EN

1H, 13C and 14N NMR chemical shifts for creatinine in water solutions of various acidity have been measured. Analysis of these data enabled determination of the acidity constant of creatininium cation and the chemical shifts of the neutral and protonated forms of creatinine. Molecular energies and carbon and nitrogen magnetic shielding constants for various tautomeric structures of the investigated species have been calculated using the quantum chemistry method GIAO DFT B3LYP/6-311++G(2d,p). Compilation of the available experimental and theoretical results has provided additional information on the problem of tautomerism of this important biological molecule.

5

Capacitive sensors based on a photografted molecularly imprinted polymers

Panasyuk-Delaney T., Mirsky V.M., Wolfbeis O.S.

Biocybernetics and Biomedical Engineering

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2001

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Vol. 21, no. 3

43-54

EN

The reversible chemosensors to creatinine and desmetryn based on artificial chemoreceptors are described. A grafted photopolymerization combined with a technique of molecular imprinting was used for the receptor layer preparation. After polymer deposition and intensive washing from templates, the electrodes were investigated by impedance spectrometry. Creatinine and desmetryn binding were detected as a decrease in the electrode capacitance. Sensor response to creatining was highly selective. No response to the addition of sodium chloride, creatine, urea or glucose were observed. The electrodes coated with the molecularly imprinted polymers selective to desmetryn displayed specific binding of this herbicide: only small capacitive effects were observed to addition of terbumeton or atrazine, while metribuzine displayed capacitance decrease similar to desmetryn.

PL

W artykule opisano odwracalne czujniki chemiczne kreatyniny i desmetryny oparte na sztucznych chemoreceptorach. W celu wykonania warstwy receptorowej użyto szczepionej fotopolimeryzacji w połączeniu z techniką znakowania molekularnego. Po nałożeniu polimeru i obmyciu substancją wzornikową, elektrody były badane metodą spektroskopii impedancyjnej. Wiązanie kreatyniny i desmetryny objawiało się w postaci zmniejszenia pojemności elektrody. Odpowiedź czujnika na kreatyninę była bardzo selektywna. Nie obserwowano odpowiedzi na dodanie chlorku sodu, kreatyny, mocznika lub glukozy. Elektrody pokryte polimerami znakowanymi molekularnie, selektywne na desmetryn wykazywały specyficzne wiązanie tego herbicydu: obserwowano tylko małe zmiany pojemności po dodaniu terbumetonu lub atrazyny, natomiast metrabuzyna wykazywała zmiany pojemności podobne do desmetrynu.