Visualising user–website interaction: description and evaluation of a teaching method

This paper presents a teaching method applied in a usability research course that is part of a bachelor degree programme at the Academy of Fine Arts in Katowice. The method employs visualisation techniques of the user–website interaction, a design practice popular in other fields, but less often used in usability studies. The theoretical background of the data visualisation method, as well as examples of its use in research, are presented and discussed in this paper. In addition to presenting the method, the paper evaluates and analyses how students have responded to it. Using the technology acceptance model, we identified the perceived usability of the method as the main factor influencing students’ behavioural intention to use it in the future.

     

Dissociation constants of aromatic carboxylic acids spread at the air/water interface

The surface potential technique is employed to estimate the dissociation constant (K) of a series of aromatic carboxylic acids in the form of Langmuir monolayers. Using electric surface potential (ΔV) measurements of monolayers spread on aqueous subphases, containing different concentrations of Na⁺, and applying the Gouy–Chapman theory as well as the Henderson–Hasselbalch equation, the surface pK for the investigated compounds falls in the range of 4.5–5.6 with the mean value of 5.1. The other method, based on surface potential measurements of monolayers of the parent, unsubstituted compound (5′-phenyl-m-terphenyl-4-carboxylic acid) spread on aqueous solutions with distinct pHs, leads to a pK of ca. 6.5 which corresponds to the bulk conditions. This value is shifted towards neutral pH as compared to the one calculated with the Henderson–Hasselbalch equation (5.3), owing to the inhomogeneous distribution of hydrogen ions caused by partial ionization of carboxylic groups of the monolayer molecules.     

Mitochondrial Oxidative Stress—A Causative Factor and Therapeutic Target in Many Diseases

The excessive formation of reactive oxygen species (ROS) and impairment of defensive antioxidant systems leads to a condition known as oxidative stress. The main source of free radicals responsible for oxidative stress is mitochondrial respiration. The deleterious effects of ROS on cellular biomolecules, including DNA, is a well-known phenomenon that can disrupt mitochondrial function and contribute to cellular damage and death, and the subsequent development of various disease processes. In this review, we summarize the most important findings that implicated mitochondrial oxidative stress in a wide variety of pathologies from Alzheimer disease (AD) to autoimmune type 1 diabetes. This review also discusses attempts to affect oxidative stress as a therapeutic avenue.     

Microfibril Associated Protein 5 (MFAP5) Is Related to Survival of Ovarian Cancer Patients but Not Useful as a Prognostic Biomarker

Ovarian cancer (OC) is usually diagnosed late due to its nonspecific symptoms and lack of reliable tools for early diagnostics and screening. OC studies concentrate on the search for new biomarkers and therapeutic targets. This study aimed to validate the MFAP5 gene, and its encoded protein, as a potential prognostic biomarker. In our previous study, we found that patients with high-grade serous OC who had higher MFAP5 mRNA levels had shorter survival, as compared with those with lower levels. Here, we used the Kaplan-Meier Plotter and CSIOVDB online tools to analyze possible associations of MFAP5 expression with survival and other clinico-pathological features. In these analyses, higher MFAP5 mRNA expression was observed in the more advanced FIGO stages and high-grade tumors, and was significantly associated with shorter overall and progression-free survival. Next, we analyzed the expression of the MFAP5 protein by immunohistochemistry (IHC) in 108 OC samples and tissue arrays. Stronger MFAP5 expression was associated with stronger desmoplastic reaction and serous vs. non-serous histology. We found no significant correlation between IHC results and survival, although there was a trend toward shorter survival in patients with the highest IHC scores. We searched for co-expressed genes/proteins using cBioPortal and analyzed potential MFAP5 interaction networks with the STRING tool. MFAP5 was shown to interact with many extracellular matrix proteins, and was connected to the Notch signaling pathway. Therefore, although not suitable as a prognostic biomarker for evaluation with a simple diagnostic tool like IHC, MFAP5 is worth further studies as a possible therapeutic target.     

Melatonin and Female Hormone Secretion in Postmenopausal Overweight Women

Estrogen deficiency is considered to be the main cause of increased appetite and increased weight in postmenopausal women. In this period, reduced secretion of melatonin (MEL) was also observed. The aim of the study was to evaluate the secretion of melatonin, 17-β estradiol and follicle-stimulating hormone (FSH) in relation to body mass index (BMI) in pre- and postmenopausal women. The study included 90 women divided into three equal groups: group I (control)—women without menstrual disorders, group II—postmenopausal women without change in appetite and body weight, group III—postmenopausal women experiencing increased appetite and weight gain. In each patient, serum melatonin, 17-β-estradiol, FSH and urine a 6-sulfatoxymelatonin (aMT6s) were determined. Compared to the control group, the level of melatonin and estradiol was statistically lower. The FSH level was higher than in the groups of postmenopausal women. No significant correlation was found in all groups between the level of melatonin and the levels of estradiol and FSH. A negative correlation was found between aMT6s excretion and BMI, and a positive correlation between the level of FSH and BMI, mainly in overweight women. The obtained results indicate a significant effect of melatonin deficiency on the process of weight gain in postmenopausal women and justify its use in treatment of these disorders.     

Cytotoxicity Study of UV-Laser-Irradiated PLLA Surfaces Subjected to Bio-Ceramisation: A New Way towards Implant Surface Modification

In this research we subjected samples of poly(L-lactide) (PLLA) extruded film to ultraviolet (193 nm ArF excimer laser) radiation below the ablation threshold. The modified film was immersed in Simulated Body Fluid (SBF) at 37 °C for 1 day or 7 days to obtain a layer of apatite ceramic (CaP) coating on the modified PLLA surface. The samples were characterized by means of optical profilometry, which indicated an increase in average roughness (Ra) from 25 nm for the unmodified PLLA to over 580 nm for irradiated PLLA incubated in SBF for 1 day. At the same time, the water contact angle decreased from 78° for neat PLLA to 35° for irradiated PLLA incubated in SBF, which suggests its higher hydrophilicity. The obtained materials were investigated by means of cell response fibroblasts (3T3) and macrophage-like cells (RAW 264.7). Properties of the obtained composites were compared to the unmodified PLLA film as well as to the UV-laser irradiated PLLA. The activation of the PLLA surface by laser irradiation led to a distinct increase in cytotoxicity, while the treatment with SBF and the deposition of apatite ceramic had only a limited preventive effect on this harmful impact and depended on the cell type. Fibroblasts were found to have good tolerance for the irradiated and ceramic-covered PLLA, but macrophages seem to interact with the substrate leading to the release of cytotoxic products.     

PSA Depletion Induces the Differentiation of Immature Neurons in the Piriform Cortex of Adult Mice

Immature neurons are maintained in cortical regions of the adult mammalian brain. In rodents, many of these immature neurons can be identified in the piriform cortex based on their high expression of early neuronal markers, such as doublecortin (DCX) and the polysialylated form of the neural cell adhesion molecule (PSA-NCAM). This molecule plays critical roles in different neurodevelopmental events. Taking advantage of a DCX-CreERT2/Flox-EGFP reporter mice, we investigated the impact of targeted PSA enzymatic depletion in the piriform cortex on the fate of immature neurons. We report here that the removal of PSA accelerated the final development of immature neurons. This was revealed by a higher frequency of NeuN expression, an increase in the number of cells carrying an axon initial segment (AIS), and an increase in the number of dendrites and dendritic spines on the immature neurons. Taken together, our results demonstrated the crucial role of the PSA moiety in the protracted development of immature neurons residing outside of the neurogenic niches. More studies will be required to understand the intrinsic and extrinsic factors affecting PSA-NCAM expression to understand how the brain regulates the incorporation of these immature neurons to the established neuronal circuits of the adult brain.     

Dosage Compensation in Females with X-Linked Metabolic Disorders

Through the use of new genomic and metabolomic technologies, our comprehension of the molecular and biochemical etiologies of genetic disorders is rapidly expanding, and so are insights into their varying phenotypes. Dosage compensation (lyonization) is an epigenetic mechanism that balances the expression of genes on heteromorphic sex chromosomes. Many studies in the literature have suggested a profound influence of this phenomenon on the manifestation of X-linked disorders in females. In this review, we summarize the clinical and genetic findings in female heterozygotic carriers of a pathogenic variant in one of ten selected X-linked genes whose defects result in metabolic disorders.     

Potential Biomarkers in Diagnosis of Renal Acanthamoebiasis

Recent studies indicate that Acanthamoeba spp. may play a significant role in kidney dysfunction. The aim of the study was to examine the levels of kidney injury molecule 1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and monocyte chemotactic protein 1 (MCP-1), as well as an activity of matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9, respectively) in the kidneys of immunocompetent and immunosuppressed mice infected with Acanthamoeba spp. The levels of KIM-1, NGAL, and MCP-1 were analyzed by enzyme-linked immunosorbent assay (ELISA), and the activity of MMPs was determined by gelatin zymography. The elevated KIM-1 level was found in the kidneys of immunocompetent mice at the beginning of Acanthamoeba spp. infection. In the immunosuppressed mice, the KIM-1 level was statistically different. The statistically decreased NGAL level was found in the kidneys of immunocompetent mice compared to the uninfected mice. In the immunocompromised mice, we found statistically significant differences in MCP-1 levels between the uninfected and infected groups. There was an increase in the expression of both MMP-2 and MMP-9 in the kidneys of immunocompetent and immunosuppressed mice infected with Acanthamoeba spp. compared to the uninfected mice. The results indicate that KIM-1, NGAL, MCP-1, MMP-2, MMP-9, and MMP-9/NGAL might be promising biomarkers of renal acanthamoebiasis.