Ireneusz Pieszyński

Influence of fourth generation poly(propyleneimine) dendrimers on blood cells

Dendrimers provide many exciting opportunities for potential biomedical applications. However, owing to their positively charged surfaces, poly(propyleneimine) (PPI) dendrimers show toxic and haemolytic activities. One of the methods for masking the peripheral cationic groups is to modify them using carbohydrate residues. In this study, three types of the fourth generation PPI dendrimers-uncoated (PPI-g4), approximately 35% maltotriose (Mal-III)-coated (PPI-g4-OS), and approximately 90% Mal-III-coated (PPI-g4-DS) were investigated by assessing their effects on red blood cell (RBC) haemolysis in samples of pure RBCs, RBCs in the presence of human serum albumin (HSA) or human plasma, and RBCs in whole blood. Lymphocyte proliferation and platelet (PLT) aggregation were also studied in the presence of various concentrations of dendrimers. Although all dendrimers examined affected all the blood cells studied, the unmodified PPI-g4 had the most damaging effect. It caused high RBC haemolysis rates and PLT aggregation and greatly inhibited lymphocyte proliferation. These effects were caused by the cationic surface of this polymer. The modification of PPI-g4 with Mal-III reduced the effect of the dendrimer on all blood cells. The presence of HSA or plasma in the buffer containing the RBCs or RBC in whole blood significantly decreased the extent of dendrimer-driven haemolysis.

Cationic phosphorus dendrimers and therapy for Alzheimer's disease

Alzheimers disease (AD) is an age-related neurodegenerative disorder characterized by the aggregation of extracellular β-amyloid and the intracellular microtubule-associated protein Tau. Neurodegeneration is associated inter alia with the activation of microglial cells, neuroinflammation, oxidative stress, and diminished transduction of impulses in cholinergic neurons. Current pharmacotherapy for AD is based mainly on modulation of acetylcholine hydrolysis, administration of non-steroidal anti-inflammatory drugs and antioxidants. Novel drugs with antiamyloidic properties are currently being sought. Cationic phosphorus dendrimers have been proven to modulate amyloidogenesis and stop the aggregation of Tau protein. An ideal drug for AD should demonstrate anti-inflammatory properties, inhibit acetylcholine hydrolysis, and have antioxidant capacity. Cationic phosphorus dendrimers (generation 3 and generation 4) show the foregoing properties. They inhibit acetylcholinesterase activity, can decrease the secretion of TNF-α, and have weak antioxidant effects. The results presented suggest that phosphorus dendrimers may be considered in the future as agents in AD therapy.

Influence of MLS laser radiation on erythrocyte membrane fluidity and secondary structure of human serum albumin

The biostimulating activity of low level laser radiation of various wavelengths and energy doses is widely documented in the literature, but the mechanisms of the intracellular reactions involved are not precisely known. The aim of this paper is to evaluate the influence of low level laser radiation from an multiwave locked system (MLS) of two wavelengths (wavelengthxa0=xa0808xa0nm in continuous emission and 905xa0nm in pulsed emission) on the human erythrocyte membrane and on the secondary structure of human serum albumin (HSA). Human erythrocytes membranes and HSA were irradiated with laser light of low intensity with surface energy density ranging from 0.46 to 4.9xa0Jxa0cm−2 and surface energy power density 195xa0mWxa0cm−2 (1,000xa0Hz) and 230xa0mWxa0cm−2 (2,000xa0Hz). Structural and functional changes in the erythrocyte membrane were characterized by its fluidity, while changes in the protein were monitored by its secondary structure. Dose-dependent changes in erythrocyte membrane fluidity were induced by near-infrared laser radiation. Slight changes in the secondary structure of HSA were also noted. MLS laser radiation influences the structure and function of the human erythrocyte membrane resulting in a change in fluidity.

The effect of MLS laser radiation on cell lipid membrane

INTRODUCTIONnAuthors of numerous publications have proved the therapeutic effect of laser irradiation on biological material, but the mechanisms at cellular and subcellular level are not yet well understood.nnnOBJECTIVEnThe aim of this study was to assess the effect of laser radiation emitted by the MLS M1 system (Multiwave Locked System) at two wavelengths (808 nm continuous and 905 nm pulsed) on the stability and fluidity of liposomes with a lipid composition similar to that of human erythrocyte membrane or made of phosphatidylocholine.nnnMATERIAL AND METHODSnLiposomes were exposed to low-energy laser radiation at surface densities 195 mW/cm2 (frequency 1,000 Hz) and 230 mW/cm2 (frequency 2,000 Hz). Different doses of radiation energy in the range 0-15 J were applied. The surface energy density was within the range 0.46 - 4.9 J/cm 2.nnnRESULTSnThe fluidity and stability of liposomes subjected to such irradiation changed depending on the parameters of radiation used.nnnCONCLUSIONSnSince MLS M1 laser radiation, depending on the parameters used, affects fluidity and stability of liposomes with the lipid content similar to erythrocyte membrane, it may also cause structural and functional changes in cell membranes.

Analysis of problems in the daily functioning of patients after hip arthroplasty.

BACKGROUNDnAwareness of functional status of patients after arthroplasty helps therapists to select suitable topics of education that will enable the patients to continue rehabilitation on their own and improve the quality of life among hip joint prosthesis recipients.nnnMATERIAL AND METHODSnThe study involved a group of 60 patients (41 men and 19 women) after arthroplasty who were hospitalised in medical rehabilitation wards of Lodz hospitals. The average age of the patients was 65.0±11.2 years (65.4±11.5 years among women and 63.9±10.8 years among men). The functional status of the patients was assessed using the modified Rankin Scale (mRS) for self-evaluation of disability, Barthel Index (BI) to determine the degree of independence in performance of daily living activities and a survey prepared by the authors.nnnRESULTSnThe degree of disability of the study subjects may be assessed as moderate (mRS score: 2.8 overall, 2.6 for women and 3.1 for men). The distributions of disability scores indicate a clinically significant difference in the assessment of disability level between women and men. The functional status of patients with regard to performance of daily living activities was evaluated as moderately severe (BI: 77.7±18.2 overall, 76.8±17.2 for women, 79.5±16.6 for men). The women after hip arthroplasty assessed their ability to dress and undress as significantly poorer than the men did.nnnCONCLUSIONSn1. The patients assessed their functional status as moderate disability. 2. The study participants faced the most serious problems with bathing, walking up and down stairs, grooming, and dressing and undressing. 3. The women assessed their ability to dress and undress as significantly poorer than the men did. 4. Physiotherapists and nurses were indicated as the main sources of education.

The Influence of the Water Baths with or Without ozone Associated with Kinesitherapy on Lower Limbs Muscles Perfusion in Patients with Gonarthrosis

Introduction: Ozone therapy is a frequently applied physiotherapy method. There are reports that ozone has a wide spectrum of possible effects. Aim: The aim of the study was to examine a possible influence of the water baths with ozone on lower limbs muscles perfusion in patients with gonarthrosis. Materials and methods: 30 patients (mean age 62,3±11,0 years) with gonarthrosis (II-III degree according to Seyfried’s scale) were included in the study. The patients were assigned to three groups: • Group A (10pts) – water massages with ozone + exercises (kinesitherapy) were applied in this group • Group B (9pts) – water massages without ozone + exercises (kinesitherapy) were applied • Group C (11pts) – kinesitherapy alone was applied. All the patients realized the same kinesitherapy program. Radioisotopic examinations of the lower limbs muscles perfusion in rest were performed before and after the treatment. Results: the study revealed a significant lower limbs muscles perfusion increase in the group A (water massages with ozone were applied in this group). A slight perfusion increase was also observed in other groups (B and C) but the differences were not statistically significant. No patient had any adverse reaction after the applied treatment. Conclusions: The study revealed a significant lower limbs muscles perfusion increase after hydrotherapy with ozone procedures. The results confirm that ozone has a positive influence on microcirculation. Ozonetherapy can be recognized as a safe method as no adverse reactions during and after the treatment were observed in the study.