Biomedical subjects

Małgorzata Sznitowska

Publications and source records attributed to Małgorzata Sznitowska.

7 recordsLinked to original sources

PubMed2004

[Tricholoma equestre--animal toxicity study].

UNLABELLED: Animal toxicity study of Tricholoma equestre mushrooms stored for 12 months at (-)20 degrees C was performed using 30 male BALB/c mice. Three groups of 5 mice each were given suspension of T. equestre powder in water, boiled aqueous extract and chloroform-methanol extract dissolved in Miglyol 812 by gavage for three consecutive days. Mice in control groups were given water, Miglyol 812 and p-phenylenediamine (CAS 106-50-3). Creatine kinase activity was determined in serum collected 72 hours after the final dose. Mean activity of serum creatine kinase in mice treated with T. equestre powder, aqueous extract, chloroform-methanol extract and Miglyol 812 were 157 +/- 93, 129 +/- 30, 96 +/- 38, 111 +/- 66 U/L respectively and did not differ significantly from mean activity in mice which were given water (107 +/- 38 U/L). Mean serum creatine kinase activity in p-phenylenediamine group (265 +/- 63 U/L) was significantly higher than in group treated with water (p<0.01). CONCLUSION: Extracts of Tricholoma equestre mushrooms stored for 12 months at (-)20 degrees C did not cause rhabdomyolysis in male BALB/c mice.

Agaricales↗

PubMed2004

Development of modified-release dosage forms containing loratadine and pseudoephedrine sulfate.

Pseudoephedrine sulfate (PES) is a short-acting sympathomimetic amine and decongestant. Loratadine (L) is a long-acting antihistamine, H1 blocker. These drugs administered together provide relief from a whole range of rhinitis (hay fever) symptoms. Combination of both drugs is available in the form of sugar-coated modified-release tablets Clarinase (Schering-Plough). In this product, 5 mg of L and 60 mg of PES is present in the sugar-coating layer ready for an immediate release, and the rest of PES (60 mg) is incorporated in the extended-release core of the tablet. This enables fast as well as prolonged release of PES over 6-8 h. Because the sugar coating technologies are troublesome and rarely used nowadays, the aim of this study was to develop alternative oral dosage forms containing L (5 mg) and PES (120 mg). It was assumed that, similarly to the original product, the total dose of L and the half dose of PES should be released during 1 h and the remaining dose of PES ought to be gradually released for up to 8 h.

Bronchodilator Agents↗

PubMed2003

pH-induced modifications to stratum corneum lipids investigated using thermal, spectroscopic, and chromatographic techniques.

The effects of nonphysiological pH on stratum corneum lipid content and structure have been studied. Human stratum corneum samples were soaked in solutions at pH 1, 2, 6, 11, or 12 for up to 24 h. After removal of the stratum corneum, the buffer solutions were analyzed for lipid composition using thin-layer chromatography analysis and the stratum corneum sheets were examined using differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The results demonstrate that only buffers of pH 11 or higher affect the stratum corneum lipids. No large difference in the contents of ceramides and cholesterol extracted by buffers of varying pH was observed. In contrast, free fatty acid extraction was pH dependent; amounts removed by 24-h treatment with pH 11 or 12 buffers were comparable, and were similar to amounts extracted with a methanol-chloroform mixture for 15 min. No appreciable changes in DSC and FTIR spectra were detected between untreated stratum corneum and stratum corneum samples treated with buffers at pHs in the range 1-6. For tissue treated with pH 11 and 12, the position of the endothermal melting peak T2 shifted from 72 to 74 degrees C on the DSC thermograms. Small changes in the broadness of spectral peaks at 2855 cm(-1) [attributable to upsilon(CH(2)) stretching of stratum corneum lipids and 1655 cm(-1) upsilon(C=O) stretching amide I band] can be seen in the FTIR spectra from the treated stratum corneum samples, although no shifts in peak positions were observed. Intensity changes in peaks from extraneous lipids [upsilon(C=O) stretching mode at 1735 cm(-1)] were observed after buffer treatments. The changes provoked by the alkaline buffers are not dramatic and it may be concluded that the stratum corneum appears remarkably resilient to extended exposure in both highly acidic (pH 1) and highly alkaline (pH 12) environments.

Adult↗

PubMed2002

[Liposomes--therapeutic progress and technological problems].

Liposomes represent globular vesicles composed of an aqueous core and one or several phospholipid bilayers. They can encapsulate hydrophilic or lipophilic drugs used in therapy and diagnostic imaging. Liposomes provide protection of the active substances, sustained or controlled release and also targeted delivery of drugs to specific cells, tissues, organs. Easy oxydation of phosphatidylcholin (lecithin)--the main membrane component--is the limitation of the introduction of liposomes to the medicinal practice in a broader scale. Unsatisfying chemical stability of lecithin has an unfavourable influence on drug and liposome stability. Liposomes decompose during storage and leakage of the encapsulated drug occurs. A review of advantages of application of liposomes in medicine and methods of increasing their stability was presented.

Antineoplastic Combined Chemotherapy Protocols↗

PubMedDate not supplied

The effect of cryoprotectants on the physical properties of large liposomes containing sodium diclofenac.

Large liposomes (1-10 microm) containing sodium diclofenac were prepared and lyophilized using lactose or mannitol (7.5% in respect to the lipid content) as cryoprotectants. The physical studies of liposomes were performed during 30 days of storage in a dry or resuspended form. Lyophilization of large liposomes and storage in the dry form at 5 degrees C increases their physical stability. Lactose is a cryoprotectant which does not influence changes of properties of liposomes regarding their size, encapsulation efficacy and release rate. Large liposomes lyophilized in the presence of mannitol tend to increase in size and encapsulation efficacy, but the lipid bilayers are stabilized and less permeable to the drug.

Cryoprotective Agents↗

PubMedDate not supplied

Feasibility of the Ph.Eur. flow-through cell for dissolution testing of the compounded rectal suppositories containing indomethacin or sodium diclofenac.

Ph.Eur. and BP have introduced a dissolution apparatus for suppositories. Suitability of the apparatus for quality control of indomethacin or sodium diclofenac (100 mg) compounded suppositories was evaluated and the effect of the type of suppository base on dissolution profiles was studied. The fastest and most reproducible release profiles were observed for hydrophilic base (macrogols). More than 80% of the drug was released during 60 min, while after 350 min 18.5-50% of the total amount was released from lipophilic bases (Witepsol and Adeps solidus). The results demonstrate that slow and non-reproducible release occurs when the lipophilic suppository base does not melt. The feasibility of the test for the formulations, which do not melt during the procedure, is questionable.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMedDate not supplied

The physical characteristics of lyophilized tablets containing a model drug in different chemical forms and concentrations.

Orodispersible tablets, usually prepared using freeze-drying method, are becoming a popular drug formulation for patients who have difficulties swallowing solid dosage forms. The influence of drug solubility and concentration on the physical characteristics of lyophilized tablets composed of mannitol and gelatin was investigated. Phenobarbital and phenobarbital sodium were studied as model drugs. The tablets were analyzed for mechanical strength using a new method employing Instron, a material testing apparatus. For tablets containing phenobarbital in the form of sodium salt, better mechanical strength was demonstrated than for tablets prepared with water insoluble phenobarbital--acid form. Besides, the mechanical characteristics of the tablets indicate that plasticity and porosity were reduced when sodium phenobarbital was incorporated at a higher dose. Lyophilized tablets were not hygroscopic and only a small increase of tablet mass by 1% and 3% was observed after 4 weeks of storage at 40% and 60% RH, respectively. All formulations disintegrated in seconds in water, at a temperature of 37 degrees C.

Drug Compounding↗