Biomedical subjects

J Sarapuk

Publications and source records attributed to J Sarapuk.

23 records · Page 2Linked to original sources

PubMedDate not supplied

Physiological activity of some organophosphorous compounds and their influence on mechanical properties of erythrocytes.

Hemolysis and fluidization of erythrocytes (RBC) membranes by some newly synthesized aminophosphonates as well as their potency to induce electrolyte efflux from cucumber (Cucumis sativus cv "Wisconsin") cotyledons were studied. Also, the chlorophyll content in aminophosphonate-treated cotyledons was affected. The compounds studied differed mainly in hydrophobicity of their substituents at the carbon, nitrogen and phosphorus atoms. It was found that aminophosphonate potency to fluidize RBC membranes depended on the combination of its overall lipophilicity and/or the kind of substituent at the P atom. Especially, iso-propyl groups enhanced that potency. The sequence of aminophosphonates that exhibited the strongest fluidization activity was paralelled by their physiological and hemolytic activities; in the latter case for these compounds that hemolyzed RBC under used concentrations. A general conclusion is that both the stereochemistry and lipophilicity determine the efficiency of the aminophosphonates studied. This efficiency is most probably related to the interaction of aminophosphonates with the lipid phase of biological objects.

Animals↗

PubMedDate not supplied

Aminophosphonate-induced changes of betacyanine and ionic efflux.

Betacyanine and ionic leakage from red beet (Beta vulgaris ssp. L. rapacea) roots and lilac (Syringa vulgaris L.) leaves under the influence of new aminophosphonates were studied by spectroscopic and conductometric methods. It was found that the leakage of dye or electrolytes depended both on the concentration of the compounds used and their structural features. The results compared to those obtained for the well known herbicide Buminafos (dibutyl 1-butylamino-1-cyclohexanephosphonate) enabled to conclude that some of the compounds studied exhibited comparable or better activity than this herbicide. That makes them potentially good herbicides. It is possible that the effects observed are the result of action on cell membranes of the tissues used. The possible role of the structural features of aminophosphonates in this action is discussed.

Asteraceae↗

PubMedDate not supplied

Physiological and hemolytic toxicity of some aminophosphonates.

The effect of novel synthesized aminophosphonates on membrane potential and electrical conductance of internodal cells of Nitellopsis obtusa and hemolysis of erythrocytes (RBC) was studied. It was found that those the organophosphorous compounds, when present at 10-100 microM concentrations, caused depolarization and increased electrical conductance of alga membranes. They also influenced fluidity of erythrocyte membranes. When used at higher concentrations aminophosphonates caused hemolysis of RBC. The changes observed depended on structural features of the aminophosphonates, i.e., substituents at the carbon, phosphorus and nitrogen atoms, and, most probably, may be the result of direct interaction of the aminophosphonates with the lipid phase of the plasma membrane and the induced structural changes. Two modes of interaction are proposed.

Amines↗

PubMedDate not supplied

Hydration of alkylammonium salt micelles--influence of bromide and chloride counterions.

The micellization process of dodecyltrimethylammonium chloride (DTAC) and bromide (DTAB) was studied. Nuclear magnetic resonance method was used. The 1H NMR and 13C NMR spectra were taken at higher and lower concentrations than the critical micelle concentrations (CMC) of the compounds studied. Chemical shifts were analysed. The studies performed were prompted by earlier calorimetric measurements which showed that there were significant qualitative and quantitative differences in the micellization process of the compounds studied. Namely, DTAB micelle dissociation was found to be an endothermic process while that of DTAC was exothermic. The differences found must be the result of differentiated influence of bromide and chloride counterions on the micellization process, including the phenomenon of micelle hydration. The objective of the work was to check whether cationic surfactant counterions can influence the micelle hydration process. Indeed, DTAB and DTAC, as monomers, exhibit similar hydrophobic hydration, but DTAB micelles are more hydrated than DTAC ones. It seems that the differences found in micellization of both salts studied may be attributed to different physicochemical properties of bromide and chloride ions, such as their mobilities and radii of their hydrated forms. Moreover, the effect of anions on the water structure must be taken into account. It is important whether the anions can be classified as water ordering kosmotropes, that hold the first hydration shell tightly, or water disordering chaotropes, that hold water molecules in that shell loosely.

Anions↗

PubMedDate not supplied

Influence of organic and inorganic ions on organolead-induced hemolysis of erythrocytes.

The influence of some inorganic (K+, Mg2+, and Al3+) and organic CnH(2n+1)SO3-, n = 12 and 14) ions was studied on the hemolysis of erythrocytes (RBC) caused by organolead compounds (tripropyllead--TPL, tributyllead--TBL and triphenyllead--TPhL chlorides). It was found that sulfonate anions increased the hemolytic effect induced by triorganoleads, while inorganic cations protected RBC against the triorganoleads action, especially when the latter were used at small concentrations. This protection was weaker when the concentration of organoleads increased and depended on the kind of ion. The protective efficacy sequence was like that: Mg2+ > Al3+ > K+. The less hemolytic of the triorganoleads studied was TPL. TBL was slightly more effective than TPhL. The efficacy of the sulfonate ions to increase the triorganolead chloride-induced hemolysis was practically the same for TPL and TBL. A weaker efficacy of C12H25SO3+ was observed when TPhL was used as RBC membrane modifier.

Animals↗