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Natural xenobiotics inducing apoptosis in hepatoma cells: in vitro study

Starosta M., Tyszka-Czochara M., Bukowska-Strakova K., Dołhańczuk-Śródka A.

Proceedings of ECOpole

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2018

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Vol. 12, No. 2

335--343

EN

The term “xenobiotics” refers to substances which are not produced within the human body, but may occur in human environment. Some of biologically active chemicals may be synthesized by plants. Many studies have been conducted with regard to plant secondary metabolites and the beneficial impact of various plant-derived compounds on human health has been demonstrated. Recent research have shown chemopreventive properties of catechins. (+)-catechin ((2R,3S)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-chromene-3,5,7-triol) and (-)-epigallocatechin gallate (EGCG; [(2R,3R)-5,7-dihydroxy-2-(3,4,5-trihydroxyphenyl)chroman-3-yl] 3,4,5-trihydroxybenzoate) are compounds abundant in daily human nutrition. Growing body of evidence reports pro-apoptotic effects of catechins. Both catechins have been shown to modulate intracellular pathways network in tumor cells thereby regulating signaling cascades, which results in programmed death of cancer cells, apoptosis. Apoptosis is one of the most potent mechanisms to defense against cancer. During apoptosis, the activation of caspases results in biochemical and morphological changes associated with specific changes in cell phenotype. Besides apoptosis, tumor cells may be also eliminated from organism via necrosis, however the latter process may evoke local inflammation, which in turn may result in detrimental effects within the body. Xenobiotics with potential to cause apoptosis of cancer cells may be considered in modern combined anticancer therapies and/or to assist existing treatments.

PL

W środowisku występują substancje obce o charakterze ksenobiotyków, czyli związków chemicznych niesyntetyzowanych w sposób naturalny w ciele człowieka. Wiele takich aktywnych biologicznie związków może być produkowanych przez rośliny. Przeprowadzone dotychczas badania wskazują, że drugorzędowe metabolity roślinne mogą wywierać pozytywny wpływ na zdrowie człowieka. Na przykład wyniki ostatnich obserwacji potwierdziły chemoprewencyjne właściwości katechin. (+)-katechina (ang. (2R,3S)-2-(3,4dihydroxyphenyl)-3,4dihydro-2H-chromene-3,5,7-triol) oraz (-)-galusan epigallokatechiny (ang. EGCG; [(2R,3R)-5,7-dihydroxy-2(3,4,5-trihydroxyphenyl)chroman-3-yl] 3,4,5-trihydroxybenzoate) to związki o charakterze ksenobiotyków występujące w diecie człowieka. Ostatnie odkrycia zwracają uwagę w szczególności na proapoptotyczne właściwości związków z tej grupy. Obydwa wymienione związki chemiczne mogą modyfikować przebieg wewnątrzkomórkowych ścieżek sygnałowych w komórkach nowotworowych. Takie oddziaływanie może uruchamiać kaskadę aktywności prowadzącą do apoptozy, programowanej śmierci komórki neoplastycznej. Apoptoza jest jednym z mechanizmów, które wykorzystuje się w nowoczesnych terapiach przeciwnowotworowych. Apoptozę charakteryzuje szereg zmian w przebiegu procesów biochemicznych i morfologii komórki. Komórki nowotworowe mogą być eliminowane również na drodze nekrozy, jednakże ten typ śmierci komórkowej często prowadzi do lokalnego stanu zapalnego, co jest zjawiskiem niekorzystnym dla organizmu. Drugorzędowe metabolity roślinne, takie jak (+)-katechina i (-)-galusan epigallokatechiny, mogą wykazywać zdolność do wywoływania śmierci apoptotycznej komórek nowotworowych i potencjał ten może być wykorzystywany w nowoczesnych przeciwnowotworowych terapiach kombinowanych lub do wspierania istniejącego leczenia.

2

Force analysis of shoulder joint muscles in the early phase of brain stroke

Starosta M., Kostka J., Miller E.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 3

107--113

EN

Upper limb impairment in the early phase of brain stroke is one of the key problems in rehabilitation. An estimation of muscle force can be a helpful factor for functional improvement after a stroke. The primary goals of this study were to determine the muscles with the lowest force in the affected (A) and non-affected (non-A) upper limb. Moreover, the differences between men and women were compared and these values were correlated with age. Methods: One hundred (n = 35 female, n = 65 male) post-stroke patients met the inclusion criteria. The mean age of the study participants was 66.1 years. Muscle force for external and internal rotators of shoulder was measured with handheld dynamometer. Moreover, the correlation coefficients for differences in muscular force with the patient’s age were estimated. Results: Our study reports that the force of the (A) side in relation to the (non-A) was by 37% weaker. We observed about a 40% decrease in the force of the shoulder’s external rotation (female – 42%; male – 41%) and shoulder’s flexion (by 38% – female; 40% – male). Significant correlations between the muscle force and the age of post-stroke patients were also found. It was concluded that about 4 weeks after the first stroke in the patient’s life, the external rotators are the most affected group of shoulder muscles. Conclusions: Neither sex nor the side of the ischemic brain injury influence the muscle force, whereas age determines both muscle force and muscle force deficits. Older post-stroke patients demonstrate fewer deficits in muscle strength than younger ones.

3

Analysis of upper limb muscle strength in the early phase of brain stroke

Starosta M., Kostka J., Redlicka J., Miller E.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 3

85--91

EN

Purpose: The aim of this study was to determine the muscles with the lowest strength in nonaffected (non-A) and affected upper limb (A), to assess differences between men and women and to correlate these values with age in patients after stroke. Methods: Sixty hospitalized in Neurorehabilitation Ward patients (40 male, 20 female), 1-2 weeks after stroke, were enrolled to the study. Their age ranged from 50 to 80 years with a mean (sd) of 65,5 (18,7) years. Muscle force values from upper limb muscles were measured using the MicroFet 2 hand-held dynamometer. The results are displayed in newtons [N], mean values of muscular force, effect sizes and confidence intervals displayed as Cohen’s d and 95% CI were determined. Moreover, we made the coefficients correlation for differences in muscular force versus the Rivermead Motor Assessment (RMA) arm section. Results: Strength of (A) upper limb in comparison to (non-A) was 39% weaker. The severely affected muscle groups were the shoulder flexion 41% (women) versus 46% (men); elbow flexion 39% (women) versus 31% (men); wrist extension 36% (women) versus 42% (men). No significant correlations were found between muscle strength results and RMA or age. Conclusions: Muscle force of (A) upper limb after stroke demonstrates 39% decrease. Men show more significant decrease than women (40% vs 35%). Functional assessment in RMA values show the better results in women (4,9 ± 4,1) than men (3,4 ± 3,2).

4

Influence of parameters of grit blasting conducted Dymet® device 412K to obtain roughness

Szyfelbain M., Charchalis A., Starosta M.

Journal of KONES

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2016

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Vol. 23, No. 4

521--526

EN

There are several fundamental steps for the technological preparation, which are required to optimize the thermal spray coatings. In order to ensure proper bonding of the coating, important is properly preparation of substrate. The surface of the substrate has to be clean and should have a suitable roughness after previously performed treatment. Knowledge about the effects of process parameters allows designing the coatings obtained with an optimal adherence. Only when all the components of the spraying coating process are used correctly there is possible properly design the technology. The article describes the impact of technological parameters of grit blasting to obtain the roughness of the steel substrate (steel S185) to the process of metallic coatings by cold gas dynamic spraying. Research was carried out by using the Dymet® 412K appliance, designed for applying metal coatings and substrate surface cleaning. Grit blasting is a mechanical method of surface preparation of metal parts. It allows obtaining a high degree of surface cleanliness and a determined roughness. The authors took into account parameters such as operational pressure, spray angle (incidence) of abrasive grit blasting in the axis of the stream and feed rate of used abrasive particles (Al2O3) passed to the nozzle of spray gun. Carried out the multiple regression analysis of the roughness parameters results. It revealed the existence of certain influences and changes of process parameters, which affect on the surface quality. Carried out calculations by using a multiple regression showed that the greatest correlation is between the required roughness and the feed rate of used abrasive particles. The studied roughness was described by the parameters: Ra, Rz, Rt and RSm. Stepped growth (from 0.1 to 0.8 g/s) of abrasive particles feed rate caused a decline of all of the roughness parameters. It has been found that the values of the roughness in the least depend on the operational pressure.

5

Technologie stosowane w pompach do ścieków

Kaźmierski T., Starosta M.

Wodociągi - Kanalizacja

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2005

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nr 10

22-24