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Effect of interferon, polyacrylin acid, and polymethacrylic acid on tail lesions on mice infected with vaccinia virus.

Intravenous inoculation of mice with vaccinia virus produced characteristic lesions of the tail surface which were suppressed by intraperitoneal administration of interferon and polyacrylic acid (PAA). Polymethacrylic acid (PMAA) stimulated the formation of vaccinia virus lesions. For full activity, both interferon and PAA must be given prior to infection. PAA was still significantly effective at small dose levels (3 mg/kg) and achieved protection for at least 4 weeks. Protection increased with increasing molecular weight of the polymer. The mode of action of PAA is discussed.

Acrylates↗

Antiviral activity of polyacrylic and polymethacrylic acids. I. Mode of action in vitro.

Polyacrylic acid (PAA) and polymethacrylic acid (PMAA) were investigated for their antiviral properties in tissue culture. Compared to other related polyanions, as dextran sulfate, polystyrene sulfonate, polyvinyl sulfate, and polyphloroglucinol phosphate, PAA and PMAA were found to be significantly more antivirally active and less cytotoxic. PMAA added 24 hr prior to virus inoculation inhibited viral growth most efficiently but it was still effective when added 3 hr after infection. Neither a direct irreversible action on the virus nor inhibition of virus penetration into the cell could explain the antiviral activity of PMAA. PMAA inhibited the adsorption of the virus to the host cell and suppressed the one-cycle viral synthesis in tissue cultures inoculated with infectious RNA.

Acrylates↗

Antiviral activity of polyacrylic and polymethacrylic acids. II. Mode of action in vivo.

A marked virus-inhibiting potency is obtained in the serum after intraperitoneal injection of polyacrylic acid (PAA) and polymethacrylic acid (PMAA) in mice. Much higher antiviral levels were reached than for other related polymers including dextran sulfate, heparin, polyvinyl sulfate, pyran copolymer, polystyrene sulfonate, and macrodex. The broad antiviral action of PAA and PMAA was attributed both to a direct interference with the virus-cell interaction and the viral ribonucleic acid metabolism and to the formation of an interferon-like factor. Both polyanions differed in interferon-inducing ability: highest serum interferon titer was obtained 18 hr after the intraperitoneal injection of PAA. The mechanism of interferon production by PAA and PMAA is discussed. As described previously for Sindbis virus and endotoxin, the animals also became hyporeactive after injection of PAA.

Acrylates↗

Lymphocytosis induced by polymethacrylic acid. Dose-effect and toxicity.

Intravenous polymethacrylic acid (PMAA) significantly increases the number of lymphocytes in the blood of the rat. The relationship between dose-effect and lymphocytosis is linear. The lethal dose in 30 days of PMAA is 120 mg/kg b.w. and the half-lethal dose 80 mg/kg b.w. The treatment with 40 mg/kg b.w. intravenous PMAA gives no toxic histological changes either in the lymph organs, the liver or the kidneys. Thus, PMAA appears to be, at present, a most suitable agent by which to provoke experimentally, migration of the reserve lymphocytes into the blood.

Acrylic Resins↗

Stimuli sensitive polymethacrylic acid microparticles (PMAA)--oral insulin delivery.

This study investigated polymethacrylic acid (PMAA) microparticles for controlled release of Insulin in oral administration. The microparticles were characterised by scanning electron microscopy (SEM) for morphological studies. The swelling behaviour and drug release profile in various pH media were studied. The % swelling of gels was found to be inversely related to the amount of crosslinker added. Inclusion complex of betaCD and Insulin was studied using polyacrylamide gel electrophoresis (PAGE). Optimum complexation was obtained in the ratio 100 mg betaCD: 200 IU Insulin. The release pattern of Insulin from Insulin-betaCD complex encapsulated PMAA microparticles showed release of Insulin for more than seven hours.

Administration, Oral↗

Resonance light scattering technique for the determination of proteins with polymethacrylic acid (PMAA).

As a resonance light scattering (RLS) probe, the polyelectrolyte polymethacrylic acid (PMAA) was applied in this assay. The bovine serum albumin (BSA) and human serum albumin (HSA) were determined by the electrostatic interaction of PMAA and proteins. At pH 3.8 Na(2)HPO(4)-citric acid buffer solution, the RLS intensities of PMAA-BSA (HSA) system were greatly enhanced. The characteristic peaks were appeared at the wavelength 320, 546 and 594 nm. The optimization conditions of the reaction were also examined and selected. Under the selected conditions, the RLS intensities were proportional to the protein concentrations in the range of (0.0200-2.00) x 10(-6) mol/L for BSA and (0.0200-2.40) x 10(-6) mol/L for HSA. The influences of some foreign substances were also examined. The synthetic samples containing proteins and some real samples were analyzed and the results obtained were satisfactory.

Animals↗

Mobilization of B and T lymphocytes and haemopoietic stem cells by polymethacrylic acid and dextran sulphate.

The leucocytosis which can be evoked by the polyanions dextran sulphate (DS), polymethacrylic acid (PMAA) and the copolymer of PMAA and styrene (PMAA--STYR) was studied in mice. After intravenous administration of these polyanions peak numbers of leucocytes were found in the peripheral blood 3 hr after injection. All three types of polyanions increased the number of lymphocytes, granulocytes and monocytes. Dose--response studies revealed that the nature of the polyanion determined the degree of leucocyte mobilization. The most potent mobilizer was found to be DS. This polyanion could evoke a six-fold increase of the number of peripheral blood leucocytes. By means of the membrane fluorescence technique it could be demonstrated that optimal doses of DS, PMAA and PMAA--STYR mobilized both B and T lymphocytes. The ratio between the number of B and T cells mobilized was greater for DS than for the other two polyanions. Intravenous injection of DS, PMAA and PMAA--STYR also increased the number of circulating haemopoietic stem cells (CFU-S). The most potent stem cell mobilizer appeared to be PMAA--STYR. This polyanion evoked a twenty-five-fold increase in the number of CFU-S.

Acrylic Resins↗

Ionization of short polymethacrylic acid: titration, DLS, and model calculations.

In this work the charging of polymethacrylic acid in excess electrolyte solution is investigated experimentally by titration and dynamic light scattering. The results are analyzed by a penetrable sphere model, which employs the Poisson-Boltzmann equation for the description of electrostatic interactions and takes into account specific binding of H+ and Na+. The evaluation of the DLS data yields two relaxation modes. The slow mode is present only at finite degrees of charging and is therefore caused by collective diffusion. The fast mode, which corresponds to diffusion coefficients in the range from (1.1 to 1.5) x 10(-10) m2 s(-1), is present over the whole pH range. This reflects the diffusional dynamics of the polyion itself and allows the calculation of hydrodynamic radii for equivalent spheres (RH). These increase from 1.5 nm at pH 2.14 up to 1.8 nm for a degree of deprotonation alpha=0.47 at pH 5.86. With a further increase of pH the radii slightly decrease to 1.6 nm. Setting the radius of the penetrable sphere equal to RH, we can successfully model the overall charging curve with logK0H=4.85 and logK0Na=-0.6. This means that weak complexes of the type COO---Na are formed, which reduce the effective charge inside the polyelectrolyte coil.

Journal Article↗

Dose response characteristics of polymethacrylic acid gel (PMAAG) for a polymerization-based dosimeter using NMR.

The radiation-response characteristics of polymetharylic acid gel dosimeter prepared with different concentrations of monomer and cross-linker is described in these studies. The dosimeters were prepared under the hypoxic condition in a glove box and were then irradiated with gamma-rays produced by Co-60 radionuclide that was generated at 1.25MeV energy. The irradiation took place at different doses ranged from 0Gy to 19Gy. Due to the radiation activities, chain-reaction polymerisation processes had taken place in the formation of polymethacrylic acid (PMAA) gel, which cause the dose response mechanism increased in the NMR relaxation rates of protons. It has been observed that for higher concentration of monomer and cross-linker, the polymerization rate was increased.

Cobalt Radioisotopes↗

Cyclodextrin-insulin complex encapsulated polymethacrylic acid based nanoparticles for oral insulin delivery.

Present investigation was aimed at developing an oral insulin delivery system based on hydroxypropyl beta cyclodextrin-insulin (HPbetaCD-I) complex encapsulated polymethacrylic acid-chitosan-polyether (polyethylene glycol-polypropylene glycol copolymer) (PMCP) nanoparticles. Nanoparticles were prepared by the free radical polymerization of methacrylic acid in presence of chitosan and polyether in a solvent/surfactant free medium. Dynamic light scattering (DLS) experiment was conducted with particles dispersed in phosphate buffer (pH 7.4) and size distribution curve was observed in the range of 500-800 nm. HPbetaCD was used to prepare non-covalent inclusion complex with insulin and complex was analyzed by Fourier transform infrared (FTIR) and fluorescence spectroscopic studies. HPbetaCD complexed insulin was encapsulated into PMCP nanoparticles by diffusion filling method and their in vitro release profile was evaluated at acidic/alkaline pH. PMCP nanoparticles displayed good insulin encapsulation efficiency and release profile was largely dependent on the pH of the medium. Enzyme linked immunosorbent assay (ELISA) study demonstrated that insulin encapsulated inside the particles was biologically active. Trypsin inhibitory effect of PMCP nanoparticles was evaluated using N-alpha-benzoyl-L-arginine ethyl ester (BAEE) and casein as substrates. Mucoadhesive studies of PMCP nanoparticles were conducted using freshly excised rat intestinal mucosa and the particles were found fairly adhesive. From the preliminary studies, cyclodextrin complexed insulin encapsulated mucoadhesive nanoparticles appear to be a good candidate for oral insulin delivery.

2-Hydroxypropyl-beta-cyclodextrin↗

Polymethacrylic acid: induction of lymphocytosis and tissue distribution.

Polmethacrylic acid (PMAA) induces up to a three-fold increase in the lymphocyte population of peripheral blood in rats, goats and calves after intravenous administration. Other routes of administration are less effective. A maximum lymphocytosis is achieved after 3 hr with all doses in excess of 30 mg PMAA/kg body weight; over the next few hours the lymphocyte level declines to normal. Granulocytes increase steadily for the first 7 hr before declining. Multiple doses of PMAA 2 hr apart failed to maintain or significantly alter the lymphocytosis. PMAA was labelled with 125I and 14C, and was traced to various sites in the rat. The greatest accumulation of radioactivity was in the spleen, lungs, liver, kidney, adrenals and mesenteric lymph nodes (with 14C-PMAA). The accumulation appeared more specific for spleen and lymph nodes since there was only a small loss of activity following removal of blood by whole body perfusion. This supports previous findings indicating that these two tissues play a major role in the development of lymphocytosis. Accumulation in the bone marrow may be indicative of stem cell mobilization. The results are discussed in terms of the lymphocytosis-inducing mechanism and the site of action of PMAA and the possible clinical application to ECIB therapy is considered.

Acrylic Resins↗