Antiproliferative Properties of Triterpenoids by ECIS Method—A New Promising Approach in Anticancer Studies?

Electric cell–substrate impedance sensing is an advanced in vitro impedance measuring system which uses alternating current to determine behavior of cells in physiological conditions. In this study, we used the abovementioned method for checking the anticancer activities of betulin and betulinic acid, which are some of the most commonly found triterpenes in nature. In our experiment, the threshold concentrations of betulin required to elicit antiproliferative effects, verified by MTT and LDH release methods, were 7.8 µM for breast cancer (T47D), 9.5 µM for lung carcinoma (A549), and 21.3 µM for normal epithelial cells (Vero). The ECIS results revealed the great potential of betulin and betulinic acid’s antitumor properties and their maintenance of cytotoxic substances to the breast cancer T47D line. Moreover, both substances showed a negligible toxic effect on healthy epithelial cells (Vero). Our investigation showed that the ECIS method is a proper alternative to the currently used assay for testing in vitro anticancer activity of compounds, and that it should thus be introduced in cellular routine research. It is also a valuable tool for live-monitoring changes in the morphology and physiology of cells, which translates into the accurate development of anticancer therapies.

Alternative Targets for Modulators of Mitochondrial Potassium Channels

Mitochondrial potassium channels control potassium influx into the mitochondrial matrix and thus regulate mitochondrial membrane potential, volume, respiration, and synthesis of reactive oxygen species (ROS). It has been found that pharmacological activation of mitochondrial potassium channels during ischemia/reperfusion (I/R) injury activates cytoprotective mechanisms resulting in increased cell survival. In cancer cells, the inhibition of these channels leads to increased cell death. Therefore, mitochondrial potassium channels are intriguing targets for the development of new pharmacological strategies. In most cases, however, the substances that modulate the mitochondrial potassium channels have a few alternative targets in the cell. This may result in unexpected or unwanted effects induced by these compounds. In our review, we briefly present the various classes of mitochondrial potassium (mitoK) channels and describe the chemical compounds that modulate their activity. We also describe examples of the multidirectional activity of the activators and inhibitors of mitochondrial potassium channels.

The Effects of Vitamin D on the Expression of IL-33 and Its Receptor ST2 in Skin Cells; Potential Implication for Psoriasis

Interleukin 33 (IL-33) belongs to the IL-1 family and is produced constitutively by epithelial and endothelial cells of various organs, such as the skin. It takes part in the maintenance of tissue homeostasis, repair, and immune response, including activation of Th2 lymphocytes. Its involvement in pathogenesis of several inflammatory diseases including psoriasis was also suggested, but this is not fully understood. The aim of the study was to investigate expression of IL-33 and its receptor, ST2, in psoriasis, and the effects of the active form of vitamin D (1,25(OH)₂D₃) on their expression in skin cells. Here we examined mRNA and protein profiles of IL-33 and ST2 in 18 psoriatic patients and healthy volunteers by qPCR and immunostaining techniques. Potential effects of 1,25(OH)₂D₃ and its receptor (VDR) on the expression of IL-33 and ST2 were tested in cultured keratinocytes, melanocytes, fibroblasts, and basal cell carcinoma cells. It was shown that 1,25(OH)₂D₃ effectively stimulated expression of IL-33 and its receptor ST2’s mRNAs in a time-dependent manner, in keratinocytes and to the lesser extends in melanocytes, but not in fibroblasts. Furthermore, the effect of vitamin D on expression of IL-33 and ST2 was VDR-dependent. Finally, we demonstrated that the expression of mRNA for IL-33 was mainly elevated in the psoriatic skin but not in its margin. Interestingly, ST2 mRNA was downregulated in psoriatic lesion compared to both marginal tissue as well as healthy skin. Our data indicated that vitamin D can modulate IL-33 signaling, opening up new perspectives for our understanding of the mechanism of vitamin D action in psoriasis therapy.

Genetic typing of Enterococcus faecium VRE strains isolated in three hospitals in Warsaw and Siedlce in 2015-2016

INTRODUCTION

Since the first report of vancomycin-resistant enterococci (VRE) in Poland, in 1996, these strains have spread in Polish hospitals, mainly due to selective pressure associated with increased use of vancomycin in the treatment of infections caused by methicillin-resistant staphylococci and Clostridium difficile. At the beginning of 2016 a growing number of patients colonized with VRE in the gastrointestinal tract was observed in the Children’s Memorial Health Institute (IPCZD). Some of these patients were transferred from other hospitals, and VRE colonization was found on admission.

AIM

To analyze genetic similarity of VRE strains isolated from patients hospitalized in IPCZD and two other hospitals in Mazovian district, genetic typing by pulsed field gel electrophoresis (PFGE) was performed.

MATERIALS AND METHODS

VRE strains were isolated from rectal swabs, and other clinical samples such as blood, cerebrospinal fluid, other body fluids, and environmental samples. A total of 56 VRE strains from IPCZD, 20 strains from Siedlce and 4 strains from patients from Grochowski Hospital in Warsaw were typed by PFGE.

RESULTS

PFGE typing revealed 4 VRE clones containing several strains with identical restriction patterns. Among VRE strains isolated from neonates hospitalized in IPCZD, two clones with 24 and 20 identical strains were found. Respectively, 16 (67%) and 12 (60%) isolates were originated from rectal swabs from patients at admission to the hospital. Clonal strains were identified in all three hospitals included in the study.

CONCLUSIONS

Our results showed that VRE strains had spread in the region. Isolation of clonal strains on admission to the hospital suggested independent VRE introductions from environment or other hospitals. Identification of clonal strains obtained from rectal swabs and other clinical samples during hospitalization indicated horizontal transmission.

Unveiling the effects of A-site substitutions on the oxygen ion migration in A2−xA′xNiO4+δ by first principles calculations

First principles calculations unveil the effects of A-site substitutions on the interstitial oxygen formation and migration energy in A_2−xA′_xNiO_4+δ.

Three types of ion channels in the cell membrane of mouse fibroblasts

Patch clamp recordings carried out in the inside-out configuration revealed activity of three kinds of channels: nonselective cation channels, small-conductance K(+) channels, and large-conductance anion channels. The nonselective cation channels did not distinguish between Na(+) and K(+). The unitary conductance of these channels reached 28 pS in a symmetrical concentration of 200 mM NaCl. A lower value of this parameter was recorded for the small-conductance K(+) channels and in a 50-fold gradient of K(+) (200 mM/4 mM) it reached 8 pS. The high selectivity of these channels to potassium was confirmed by the reversal potential (-97 mV), whose value was close to the equilibrium potential for potassium (-100 mV). One of the features of the largeconductance anion channels was high conductance amounting to 493 pS in a symmetrical concentration of 200 mM NaCl. The channels exhibited three subconductance levels. Moreover, an increase in the open probability of the channels at voltages close to zero was observed. The anion selectivity of the channels was low, because the channels were permeable to both Cl(-) and gluconate - a large anion. Research on the calcium dependence revealed that internal calcium activates nonselective cation channels and small-conductance K(+) channels, but not largeconductance anion channels.

An Interplay between Obesity and Inflammation in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is traditionally defined as hyperglycemia first detected in pregnancy. The risk of GDM is much higher among obese women than in their lean counterparts. An excess of adipose tissue leads to immune and inflammatory responses of both white adipose tissue and the placenta, contributing to systemic inflammation. Although the significance of both obesity and inflammation is relatively well characterized in GDM, the molecular mechanisms involved are not fully defined and require further study. In recent years huge progress has been made in identifying the intracellular signaling pathways involved in the pathophysiology of GDM. However, currently available data regarding inflammation and obesity in women with GDM are still conflicting or incomplete. We discuss selected aspects of the problem and propose future directions for research in the hope of achieving a better understanding of the disease. In particular, this review highlights recent studies exploring molecular alterations related to insulin resistance, inflammation of the adipose tissue and the placenta, lipotoxicity or endotoxemia.

Serum Heat Shock Protein 90 Alpha: A New Marker of Hypertension-Induced Endothelial Injury?

BACKGROUND

Hypertension-induced endothelial dysfunction is associated with an impaired bioavailability of nitric oxide regulated through interactions between nitric oxide synthase and heat shock protein-90 (Hsp-90). The role of Hsp-90 in the development of arterial hypertension remains unclear.

OBJECTIVES

The objective of the study was to evaluate serum concentrations of Hsp-90a in patients with arterial hypertension in comparison to their normotensive counterparts.

MATERIAL AND METHODS

The study was performed on 49 adults (mean age 55.6 years) with an elevated waist circumference. The individuals presented no subjective feeling of any disease, admitted no drug treatment for any condition, and had not previously been diagnosed with the metabolic syndrome. Patients were screened for arterial hypertension and other component disorders of the metabolic syndrome. Hsp-90a concentrations were evaluated by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Twenty-eight subjects were diagnosed with arterial hypertension, while 21 individuals had normal blood pressure. Twenty-five patients satisfied the metabolic syndrome diagnostic criteria. Hsp-90a concentrations were significantly higher (p = 0.002) in the individuals with arterial hypertension than in their normotensive counterparts (median ± interquartile range): 19.42 ng/mL ± 5.17 vs. 16.86 ng/mL ± 3.18. The concentrations of Hsp-90a correlated positively with systolic blood pressure (R = 0.39; p = 0.005) and diastolic blood pressure (R = 0.29; p = 0.046).

CONCLUSIONS

An increase in Hsp-90a concentrations in patients with arterial hypertension may be a compensatory mechanism for the impaired bioavailability of nitric oxide. The role of Hsp-90a as an early marker of hypertension-associated endothelial injury should be confirmed in further studies on a larger group of patients.

Modulation of the mitochondrial large-conductance calcium-regulated potassium channel by polyunsaturated fatty acids

Polyunsaturated fatty acids (PUFAs) and their metabolites can modulate several biochemical processes in the cell and thus prevent various diseases. PUFAs have a number of cellular targets, including membrane proteins. They can interact with plasma membrane and intracellular potassium channels. The goal of this work was to verify the interaction between PUFAs and the most common and intensively studied mitochondrial large conductance Ca(2+)-regulated potassium channel (mitoBKCa). For this purpose human astrocytoma U87 MG cell lines were investigated using a patch-clamp technique. We analyzed the effects of arachidonic acid (AA); eicosatetraynoic acid (ETYA), which is a non-metabolizable analog of AA; docosahexaenoic acid (DHA); and eicosapentaenoic acid (EPA). The open probability (Po) of the channel did not change significantly after application of 10μM ETYA. Po increased, however, after adding 10μM AA. The application of 30μM DHA or 10μM EPA also increased the Po of the channel. Additionally, the number of open channels in the patch increased in the presence of 30μM EPA. Collectively, our results indicate that PUFAs regulate the BKCa channel from the inner mitochondrial membrane.

A cartilage-inspired lubrication system

Articular cartilage is an example of a highly efficacious water-based, natural lubrication system that is optimized to provide low friction and wear protection at both low and high loads and sliding velocities. One of the secrets of cartilage's superior tribology comes from a unique, multimodal lubrication strategy consisting of both a fluid pressurization mediated lubrication mechanism and a boundary lubrication mechanism supported by surface bound macromolecules. Using a reconstituted network of highly interconnected cellulose fibers and simple modification through the immobilization of polyelectrolytes, we have recreated many of the mechanical and chemical properties of cartilage and the cartilage lubrication system to produce a purely synthetic material system that exhibits some of the same lubrication mechanisms, time dependent friction response, and high wear resistance as natural cartilage tissue. Friction and wear studies demonstrate how the properties of the cellulose fiber network can be used to control and optimize the lubrication and wear resistance of the material surfaces and highlight what key features of cartilage should be duplicated in order to produce a cartilage-mimetic lubrication system.

Supracolloidal multivalent interactions and wrapping of dendronized glycopolymers on native cellulose nanocrystals

Cellulose nanocrystals (CNCs) are high aspect ratio colloidal rods with nanoscale dimensions, attracting considerable interest recently due to their high mechanical properties, chirality, sustainability, and availability. In order to exploit them for advanced functions in new materials, novel supracolloidal concepts are needed to manipulate their self-assemblies. We report on exploring multivalent interactions to CNC surface and show that dendronized polymers (DenPols) with maltose-based sugar groups on the periphery of lysine dendrons and poly(ethylene-alt-maleimide) polymer backbone interact with CNCs. The interactions can be manipulated by the dendron generation suggesting multivalent interactions. The complexation of the third generation DenPol (G3) with CNCs allows aqueous colloidal stability and shows wrapping around CNCs, as directly visualized by cryo high-resolution transmission electron microscopy and electron tomography. More generally, as the dimensions of G3 are in the colloidal range due to their ~6 nm lateral size and mesoscale length, the concept also suggests supracolloidal multivalent interactions between other colloidal objects mediated by sugar-functionalized dendrons giving rise to novel colloidal level assemblies.

Direct measurements of non-ionic attraction and nanoscaled lubrication in biomimetic composites from nanofibrillated cellulose and modified carboxymethylated cellulose

There is a growing interest to design biomimetic self-assembled composite films from renewable resources aimed at a combination of high toughness, strength and stiffness. However, the relationship between interfacial interactions of the components and the mechanical performance of the composite is still poorly understood. In this work we present evidence of the link between mechanical performance of carbohydrate-based composites with nanolubrication and with direct surface forces between the hard and soft domain in the system. Our approach was to use nanofibrillated cellulose (NFC) as the major reinforcing domain and to modify it by adsorption of a small amount of soft polyethylene glycol grafted carboxymethyl cellulose (CMC-g-PEG). The effect of the soft polymer on direct normal and friction forces in air between cellulose surfaces was evaluated using colloidal probe microscopy. The fibrillar structure of the NFC thin film affected the frictional behaviour; when decreasing load, the friction between pure cellulose surfaces increased, suggesting partial pull-out of fibrils, a phenomenon not observed for non-fibrillar cellulose substrates. Adsorption of CMC-g-PEG on both surfaces decreased the friction considerably but adhesion was still high. The symmetric system, having both cellulose substrates covered with the polymer, was compared to asymmetric systems where only one surface was covered with the polymer. Furthermore, a free standing composite film was prepared by non-ionic self-assembly of NFC and CMC-g-PEG with 99 : 1 weight-ratio; the mechanical properties of the macroscopic films were related to the nanoscaled interactions between the components. The composition studied showed excellent mechanical properties which do not follow the simple rule of mixture. Thus, a synergy in the direct surface forces and mechanical properties was found. This approach offers a robust path to aid in the efficient design of next generation biomimetic composites.

Mitochondria as a pharmacological target: magnum overview

Mitochondria, responsible for energy metabolism within the cell, act as signaling organelles. Mitochondrial dysfunction may lead to cell death and oxidative stress and may disturb calcium metabolism. Additionally, mitochondria play a pivotal role in cardioprotective phenomena and a variety of neurodegenerative disorders ranging from Parkinson's to Alzheimer's disease. Mitochondrial DNA mutations may lead to impaired respiration. Hence, targeting the mitochondria with drugs offers great potential for new therapeutic approaches. The purpose of this overview is to present the recent state of knowledge concerning the interactions of various substances with mitochondria.

In situ determination of lignin phenolics and wood solubility in imidazolium chlorides using (31)P NMR

Corn stover, Norway spruce, and Eucalyptus grandis were pulverized to different degrees. These samples were subjected to quantitative analyses, upon the basis of predissolution into the imidazolium chloride-based ionic liquids [amim]Cl and [bnmim]Cl followed by labeling of hydroxyl groups as phosphite esters and quantitative (31)P NMR analysis. Analysis of different pulverization degrees provided semiempirical data to chart the solubility of Norway spruce in these ionic liquids. Further method refinment afforded an optimized method of analysis of the lignin phenolic functionalities, without prior isolation of the lignin from the fiber. The lignin in these samples was further enriched using cellulase and acidolysis treatments, allowing for comparison with the fibrous samples. Analysis of all samples charts the polymerized-monomer availability for each stage of the treatment. Conditions required for adequate signal-to-noise ratios in the (31)P NMR analysis were established with a notable improvement observed upon the lignin enrichment steps.

Temperament traits of children with episodic tension-type headaches

BACKGROUND

The association between headache and stress is discussed. A powerful source of stress and the ways of relation between stress and headache can differed. The individual vulnerability to stress may be related to one's temperament.

OBJECTIVE

The purpose of the present study was to evaluate the role of temperament traits in children with episodic tension-type headaches (ETTH).

METHODS

We examined 120 children, 6-16 years of age, in the Department of Developmental Neurology of the Medical University of Gdansk. All children were diagnosed with ETTH. The control group consisted of 60 age-matched children without headaches. The following instruments of assessment were used: survey-interview, EAS Temperament Survey (Buss and Plomin), and Stress Response Scale (Chandler). The results were evaluated using statistical analysis.

RESULTS

Our results showed differences in temperament traits in children with ETTH compared to children without headaches. The former demonstrated greater temperament instability, i.e., higher emotionality, an intensified level of fear, a lower level of vigour, and a higher level of shyness compared to the control group.

CONCLUSION

Children with ETTH have some different traits than children without headache.

Arginine catabolism in Aspergillus nidulans is regulated by the rrmA gene coding for the RNA-binding protein

Expression of Aspergillus nidulans arginine catabolism genes, agaA and otaA, is regulated at the level of transcription by a specific induction and two global carbon and nitrogen repression systems. Post-transcriptional and/or post-translational mechanisms have also been proposed to operate additionally. Gene tagging with transposon impala allowed us to select the rrmA gene. RRMA protein contains three conserved RRM domains, typical for RNA-binding proteins. The gene has a complex structure with several potential transcription start sites, an exceptionally long intron in 5'UTR and few uORFs in the intron. RRMA is highly conserved among fungi. Its homologues, Csx1p of Schizosaccharomyces pombe and Ngr1p of Saccharomyces cerevisiae, participate in the post-transcriptional regulation of specific genes by modifying transcript stability. Levels of otaA and agaA transcripts in the rrmA::impala loss of function mutant grown under inducing conditions are significantly higher than in the wild type strain. We propose that RRMA participates in a mechanism promoting agaA and otaA mRNA degradation. The rrmA::impala mutation has pleiotropic character and results in a slow growth phenotype indicating that rrmA functions are not limited to the regulation of arginine catabolism.

[Clinical characteristics of migraine in children according to the age]

We investigated 100 children with migraine admitted to the Developmental Neurology Department, Medical University of Gdańsk between 1988-1997. The diagnosis was made on IHS Criteria (1988). There were 53 children with migraine with aura and 47--without aura. The children were divided into three groups according to the onset of migraine attacks (3-16 years of age). To reveal the relation between clinical manifestation of migraine and the age, statistical analysis was made. The results showed that a higher frequency of migraine with aura was observed in the oldest group of children. Boys were more predisposed to develop migraine earlier. The headaches most often were pulsatile and located in the forehead, rarely-lateralized. There was no relation between location of headache, age, sex and type of migraine. In 63% of children the duration of headache was above 2 hours, in 37%--from few minutes to 2 hours. Vomiting was noticed in two thirds of patients, phonophobia and photophobia were observed in 20 children with migraine without aura and in 5 children with migraine with aura. The frequency of migraine attacks was higher in migraine without aura. Aura symptoms were mainly sensory and visual. CT and MRI were negative.

[A case of binocular blindness in small cell lung cancer]

A was reported case of binocular blindness associated with small cell lung cancer. Most probably this complication was a clinical manifestation of the paraneoplastic syndrome. No tumor response was induced with chemotherapy and patient died due to tumor progression.

[Prevalence of COPD in Gdansk sea port workers]

The purpose of the study was to evaluate prevalence of COPD in sea-port workers who has been employed with handling phosphoric compounds, sulphur compounds and grain. Smoking habits has been also analysed. Study group consists of 238 persons working in Gdańsk sea-port. Protocol of the study has included: medical history, detailed description of work place, smoking habit analysis and spirometric study. As a spirometric parameters FEV1, FVC, FEV1%VC, PEF, MEF25%VC, MEF50%VC and MEF75%VC has been assessed. In study group 106 persons worked with phosphoric compounds handling, 42 persons with sulphuric compounds handling and 90 persons with grain handling. COPD had been diagnosed in 55 persons--43 smokers and 12 non-smokers. Mean values of FEV1% in groups with equal 10-20 years time-work has been compared. Typical COPD features has been present in 37 persons--25 smokers and 12 non-smokers. COPD has been defined based on medical history, physical examination and no response o FEV1 after bronchodilatator application (Berodual).

CONCLUSION

Smoking habits in Gdańsk sea-port workers has been more important factor in COPD development than work place toxicities.

[The influence of passive smoking on the respiratory tract]

The harmful effects of passive smoking are well known and proved. A cause-and-effect relationship between involuntary inhalation of cigarette smoke and increased number of various respiratory diseases either in children or in adults is now clearly established. Many publications indicate that the respiratory consequences of passive smoking in humans may include nonmalignant disease in addition to lung cancer. It has been observed that children exposed to cigarette smoke have more frequently asthma and other wheezing diseases. An influence of the passive smoking on the pulmonary function tests has been also widely examined. A functional disorders especially of bronchioles have been detected. Since adverse effects of passive smoking on human health are proved there is a necessity to enable life in the environment free from cigarette smoke.

[Thoracoscopy]

The purpose of the work is presentation of own experience in the use of thoracoscopy in patients with pathological pleural changes. In the years 1989-1991 in the Chair and Department of Pulmonology and Tuberculosis, Medical Academy in Gdańsk, 20 thoracoscopies were performed with simultaneous taking of material for histopathological examination. In 15 patients from this group the diagnosis was made confirming the aetiology of pleural pathological changes. It should be stressed that in the group of patients with suspected malignancy, the diagnosis was confirmed in 100% of cases. Thoracoscopy is a useful diagnostic procedure during which aimed pleural biopsy may be performed.