Showing papers by "Gdańsk Medical University published in 2022"

Microorganisms from starter and protective cultures - Occurrence of antibiotic resistance and conjugal transfer of tet genes in vitro and during food fermentation

Abstract: This study analyzed antibiotic resistance and the occurrence of resistance genes in strains from starter and protective cultures. The largest number of obtained strains belonged to the genus Lactobacillus (n = 26; 44.9%), followed by Lactococcus (n = 17; 29.3%), Pediococcus (n = 8; 13.8%), Streptococcus (n = 4; 6.9%), Staphylococcus (n = 2; 3.4%) and Leuconostoc (n = 1; 1.7%). Among all strains, the highest Minimum Inhibitory Concentrations (MICs) were noted for tetracycline (max. >256 μg/ml), kanamycin (max. 48 μg/ml) and chloramphenicol (max. 32 μg/ml). The most common resistance genes were aph(3’)-IIIa (n = 35; 60.3%) and cat (n = 32; 55.2%). Strains derived from starter and protective cultures have the ability to horizontally transfer resistance genes in vitro and in situ. It should be noted that antibiotic resistance of bacteria from starter and protective cultures does not present an immediate risk to consumers. However, these microorganisms could become an environmental reservoir of antibiotic resistance. The obtained results indicate that antibiotic resistance in starter and protective cultures is not a critical issue, however it creates a concern that cannot be ignored.

Microorganisms from starter and protective cultures - Occurrence of antibiotic resistance and conjugal transfer of tet genes in vitro and during food fermentation

Abstract: This study analyzed antibiotic resistance and the occurrence of resistance genes in strains from starter and protective cultures. The largest number of obtained strains belonged to the genus Lactobacillus (n = 26; 44.9%), followed by Lactococcus (n = 17; 29.3%), Pediococcus (n = 8; 13.8%), Streptococcus (n = 4; 6.9%), Staphylococcus (n = 2; 3.4%) and Leuconostoc (n = 1; 1.7%). Among all strains, the highest Minimum Inhibitory Concentrations (MICs) were noted for tetracycline (max. >256 μg/ml), kanamycin (max. 48 μg/ml) and chloramphenicol (max. 32 μg/ml). The most common resistance genes were aph(3’)-IIIa (n = 35; 60.3%) and cat (n = 32; 55.2%). Strains derived from starter and protective cultures have the ability to horizontally transfer resistance genes in vitro and in situ . It should be noted that antibiotic resistance of bacteria from starter and protective cultures does not present an immediate risk to consumers. However, these microorganisms could become an environmental reservoir of antibiotic resistance. The obtained results indicate that antibiotic resistance in starter and protective cultures is not a critical issue, however it creates a concern that cannot be ignored. • The study involved examining 58 strains from starter and protective cultures. • Majority of the strains had high MIC to tetracycline, kanamycin and chloramphenicol. • Majority of the strains carried aph(3′)-IIIa and cat genes. • Horizontal gene transfer were observed both in vitro and in situ .

Modeling the Structure, Dynamics, and Transformations of Proteins with the UNRES Force Field.

Abstract: The physics-based united-residue (UNRES) model of proteins ( www.unres.pl ) has been designed to carry out large-scale simulations of protein folding. The force field has been derived and parameterized based on the principles of statistical-mechanics, which makes it independent of structural databases and applicable to treat nonstandard situations such as, proteins that contain D-amino-acid residues. Powered by Langevin dynamics and its replica-exchange extensions, UNRES has found a variety of applications, including ab initio and database-assisted protein-structure prediction, simulating protein-folding pathways, exploring protein free-energy landscapes, and solving biological problems. This chapter provides a summary of UNRES and a guide for potential users regarding the application of the UNRES package in a variety of research tasks.

A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification.

Abstract: The article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with different structures were trained to find the best structure to classify anomalies. The influence of various parameters of network structures on the overall accuracy of classification was examined. For the best networks, class prediction rates were examined. Activations of selected convolutional layers were studied and visualized to present how the network works in a friendly and understandable way. The best convolutional neural network for detecting vessel movement anomalies has been proposed. The proposed CNN is compared with multiple baseline algorithms trained on the same dataset.

Quality Control of Bacterial Extracellular Vesicles with Total Protein Content Assay, Nanoparticles Tracking Analysis, and Capillary Electrophoresis

Abstract: Extracellular vesicles (EVs) were isolated from Pectobacterium zantedeschiae culturing media using direct ultracentrifugation (UC), iodixanol cushion ultracentrifugation (ICUC), and iodixanol density gradient ultracentrifugation (IDGUC) techniques. The isolates were characterized with total protein content assay (bicinchoninic acid assay, BCA), nanoparticles tracking analysis (NTA), and capillary electrophoresis (CE). A satisfactory correlation (R2 > 0.94) between quantitative results obtained with BCA, NTA and CE was achieved only for isolates obtained with the IDGUC. The correlation between protein content and CE was proved to be related to the isolates’ purity. The NTA was found unable to provide reliable information on EVs quantity in samples isolated with UC and ICUC, due to the co-isolated particulate impurities. Moreover, the work reports polysaccharides, used as culturing media components, as a potential source of bias of quantitation with total protein content assay and NTA. The study demonstrates the advantageous selectivity of CE in quality control of EVs and its ability to differentiate subpopulations of EVs of Pectobacterium.

Retinal nerve fiber and ganglion cell complex layer thicknesses mirror brain atrophy in patients with relapsing-remitting multiple sclerosis

Abstract: Multiple sclerosis (MS) is associated with progressive brain atrophy, which in turn correlates with disability, depression, and cognitive impairment. Relapsing-remitting multiple sclerosis (RRMS) is a type of MS in which relapses of the disease are followed by remission periods. This is the most common type of the disease. There is a significant need for easy and low-cost methods to these cerebral changes. Changes in retinal layer thickness may reflect alterations in brain white and gray matter volumes. Therefore, this paper aims to determine whether retinal layer thickness, measured using optical coherence tomography (OCT), correlates with volumetric brain assessments obtained by magnetic resonance imaging (MRI).This retrospective cohort study recruited 53 patients with relapsing-remitting MS who underwent MRI and OCT examinations for evaluation of brain compartment volumes and thickness of retinal layers, respectively. OCT parameters, including central retinal thickness; retinal nerve fiber layer thickness (RNFL, peripapillary thickness); ganglion cell complex thickness (GCC, macular thickness); and Expanded Disability Status Scale (EDSS) results were compared with MRI parameters (cerebral cortex; cerebral cortex and basal ganglia combined; brain hemispheres without the ventricular system; and white matter plaques). We also checked whether there is a correlation between the number of RRMS and OCT parameters.Our primary objective was to identify whether these patients had retinal thickness changes, and our secondary objective was to check if those changes correlated with the MRI brain anatomical changes.RNFL and GCC thicknesses were strongly (p-value < 0.05) associated with (i) cerebral cortex volume, (ii) combination of brain cortex and basal ganglia volumes, and (iii) the hemispheres but without the ventricular system. White matter plaques (combined) showed only weak or no correlation with RNFL and GCC. There was no correlation between central retinal thickness and brain compartment volumes, and there were weak or no correlations between the summary EDSS scores and OCT results.Retinal layer thickness measured by OCT correlates with select volumetric brain assessments on MRI. During the course of RRMS, the anatomo-pathological structure of the retina might serve as a surrogate marker of brain atrophy and clinical progression within selected domains.

Quantification of Compatibility Between Polymeric Excipients and Atenolol Using Principal Component Analysis and Hierarchical Cluster Analysis.

Abstract: An important challenge to overcome in the solid dosage forms technology is the selection of the most biopharmaceutically efficient polymeric excipients. The excipients can be selected, among others, by compatibility studies since incompatibilities between ingredients of the drug formulations adversely affect their bioavailability, stability, efficacy, and safety. Therefore, new, fast, and reliable methods for detecting incompatibility are constantly being sought. Hence, the purpose of this work was to assess the usefulness of a heating, cooling, and reheating differential scanning calorimetry (DSC) program for detecting potential incompatibilities between atenolol, an active pharmaceutical ingredient (API), and polymeric excipients. Hot-stage microscopy (HSM), Fourier transform infrared (FTIR) spectroscopy, and powder X-ray diffraction (PXRD) were used as supporting techniques. Additionally, principal component analysis (PCA) and hierarchical cluster analysis (HCA) served as tools to support the interpretation of the data acquired from the DSC curves and FTIR spectra. As the alterations in the shape of the DSC peak of atenolol which are indicative of incompatibility are visible only on the cooling and reheating curves of the mixtures, the DSC heating-cooling-reheating program was found to be very useful for identifying potential incompatibilities in the binary mixtures of atenolol and polymeric excipients. The melting and recrystallization of atenolol alone and in its mixtures were also confirmed by HSM, while FTIR displayed changes in the spectra of mixtures due to incompatibility. These studies revealed that atenolol is incompatible with hydroxyethylcellulose, hypromellose, and methylcellulose. PXRD measurements at room temperature revealed that the crystallinity of atenolol did not change in these mixtures. However, its crystallinity was reduced in the mixtures previously heated up to 155 °C and then cooled to 25 °C.

Post-marathon Decline in Right Ventricular Radial Motion Component Among Amateur Sportsmen

Abstract: Moderate physical activity has a positive impact on health, although extreme forms of sport such as marathon running may trigger exercise-induced cardiac fatigue. The explicit distinction between the right ventricular (RV) physiological response to training and maladaptive remodeling has not yet been determined. In this study, we aimed to analyze the impact of running a marathon on RV mechanics in amateur athletes using three-dimensional (3D) echocardiography (ECHO) and the ReVISION method (RV separate wall motion quantification). A group of 34 men with a mean age of 40 ± 8 years who successfully finished a marathon underwent ECHO three times, i.e., 2 weeks before the marathon (stage I), at the marathon finish line (stage II), and 2 weeks after the marathon (stage III). The ECHO findings were then correlated with the concentrations of biomarkers related to myocardial injury and overload and also obtained at the three stages. On finishing the marathon, the amateur athletes were found to have a significant (p < 0.05) increase in end-diastolic (with a median of 51.4 vs. 57.0 ml/m2) and end-systolic (with a median of 24.9 vs. 31.5 ml/m2) RV volumes indexed to body surface area, reduced RV ejection fraction (RVEF) (with a median of 51.0% vs. 46.0%), and a decrease in RV radial shortening [i.e., radial EF (REF)] (with a mean of 23.0 ± 4.5% vs. 19.3 ± 4.2%), with other RV motion components remaining unchanged. The post-competition decrease in REF was more evident in runners with larger total volume of trainings (R2 = 0.4776, p = 0.0002) and higher concentrations of high-sensitivity cardiac troponin I (r = 0.43, p < 0.05) during the preparation period. The decrease in REF was more prominent in the training of marathoners more than 47 km/week. At stage II, marathoners with a more marked decrease in RVEF and REF had higher galectin-3 (Gal-3) levels (r = -0.48 and r = -0.39, respectively; p < 0.05). Running a marathon significantly altered the RV performance of amateur athletes. Transient impairment in RV systolic function resulted from decreased radial shortening, which appeared in those who trained more extensively. Observed ECHO changes correlated with the concentrations of the profibrotic marker Gal-3.

Immunosenescence and Alzheimer’s Disease

Abstract: Alzheimer’s disease (AD) is the most frequent cause of dementia due to neurodegeneration. It is stated that the most important risk factor for the late onset AD development is age. AD develops during decades and appears most of the time after 65 years of age. Even though its incidence is increasing with age but not all the centenarians are suffering from AD. The most important underlying age-related factor is immunosenescence/inflammaging. Indeed, aging is associated with immune changes which are thought to be the most prevalent cause of the age-related chronic inflammatory diseases. However, it is now postulated that the changes occurring with aging in the immune system may not be only detrimental but also adaptive. Therefore, in this review we will describe whether and how immunosenescence/inflammaging may contribute to the development of AD. We will also examine whether this can lead to novel treatment approaches different form the current.

A novel in vivo approach to assess strains of the human abdominal wall under known intraabdominal pressure

Abstract: The study concerns mechanical behaviour of a living human abdominal wall. A better mechanical understanding of a human abdominal wall and recognition of its material properties is required to find mechanically compatible surgical meshes to significantly improve the treatment of ventral hernias. A non-invasive methodology, based on in vivo optical measurements is proposed to determine strains of abdominal wall corresponding to a known intraabdominal pressure. The measurement is performed in the course of a standard procedure of peritoneal dialysis. A dedicated experimental stand is designed for the experiment. The photogrammetric technique is employed to recover the three-dimensional surface geometry of the anterior abdominal wall at the initial and terminal instants of the dialysis. This corresponds to two deformation states, before and after filling the abdominal cavity with dialysis fluid. The study provides information on strain fields of living human abdominal wall. The inquiry is aimed at principal strains and their directions, observed at the level from -10% to 17%. The intraabdominal pressure related to the amount of introduced dialysis fluid measured within the medical procedure covers the range 11-18.5 cmH2O. The methodology leads to the deformation state of the abdominal wall according to the corresponding loading conditions. Therefore, the study is a step towards an identification of mechanical properties of living human abdominal wall.

Comprehensive cancer-oriented biobanking resource of human samples for studies of post-zygotic genetic variation involved in cancer predisposition

Abstract: The progress in translational cancer research relies on access to well-characterized samples from a representative number of patients and controls. The rationale behind our biobanking are explorations of post-zygotic pathogenic gene variants, especially in non-tumoral tissue, which might predispose to cancers. The targeted diagnoses are carcinomas of the breast (via mastectomy or breast conserving surgery), colon and rectum, prostate, and urinary bladder (via cystectomy or transurethral resection), exocrine pancreatic carcinoma as well as metastases of colorectal cancer to the liver. The choice was based on the high incidence of these cancers and/or frequent fatal outcome. We also collect age-matched normal controls. Our still ongoing collection originates from five clinical centers and after nearly 2-year cooperation reached 1711 patients and controls, yielding a total of 23226 independent samples, with an average of 74 donors and 1010 samples collected per month. The predominant diagnosis is breast carcinoma, with 933 donors, followed by colorectal carcinoma (383 donors), prostate carcinoma (221 donors), bladder carcinoma (81 donors), exocrine pancreatic carcinoma (15 donors) and metachronous colorectal cancer metastases to liver (14 donors). Forty percent of the total sample count originates from macroscopically healthy cancer-neighboring tissue, while contribution from tumors is 12%, which adds to the uniqueness of our collection for cancer predisposition studies. Moreover, we developed two program packages, enabling registration of patients, clinical data and samples at the participating hospitals as well as the central system of sample/data management at coordinating center. The approach used by us may serve as a model for dispersed biobanking from multiple satellite hospitals. Our biobanking resource ought to stimulate research into genetic mechanisms underlying the development of common cancers. It will allow all available "-omics" approaches on DNA-, RNA-, protein- and tissue levels to be applied. The collected samples can be made available to other research groups.

Psychosocial predictors of persistent low back pain in patients presenting to the emergency department.

Abstract: Objectives Chronic low back pain is an important public health problem, generating high financial and social costs. While most clinical guidelines stress the importance of managing low back pain in primary care, in practice a disproportionate amount of patients with low back pain present to emergency departments. Patients presenting to emergency departments may form a specific group with different factors leading to chronicity. This prospective cohort study aimed to determine the sociodemographic and psychological predictors of persistent low back pain and the length of sick leave due to pain in patients with acute symptoms visiting an emergency department. Methods Patients with a first episode of non-specific acute low back pain in at least three months were qualified for this study. The participants filled a battery of questionnaires, including measures of pain, pain-related disability, depression, anxiety and pain coping strategies. A structured telephone interview was performed after three months with questions regarding pain and the length of sick leave. Results 110 patients participated in the study. 97 patients completed the follow-up, with 70.1% suffering from pain after three months. Lower self-rated health predicted pain after three months. Longer length of sick leave was predicted by lower self-rated health, distraction as a coping strategy and decreased behavioral activity. Conclusion Because of its simplicity, a measurement of self-rated health may be included in future clinical practice for assessing the risk of persistent pain.

Induction of 2-hydroxycatecholestrogens O-methylation: A missing puzzle piece in diagnostics and treatment of lung cancer

Abstract: Lung cancer is one of the most common cancers worldwide, causing nearly one million deaths each year. Herein, we present the effect of 2-methoxyestradiol (2-ME), the endogenous metabolite of 17β-estradiol (E2), on non-small cell lung cancer (NSCLC) cells. We observed that 2-ME reduced the viability of lung adenocarcinoma in two-dimensional (2D) and three-dimensional (3D) spheroidal A549 cell culture models. Molecular modeling was carried out aiming to visualize amino acid residues within binding pockets of the acyl-protein thioesterases, namely 1 (APT1) and 2 (APT2), and thus to identify which ones were more likely involved in the interaction with 2-ME. Our findings suggest that 2-ME acts as an APT1 inhibitor enhancing protein palmitoylation and oxidative stress phenomena in the lung cancer cell. In order to support our data, metabolomics of blood serum from NSCLC patients was also performed. Moreover, computational analysis suggests that 2-ME as compared to other estrogen metabolism intermediates is relatively safe in terms of its possible non-receptor bioactivity within healthy human cells due to a very low electrophilic potential and hence no substantial risk of spontaneous covalent modification of biologically protective nucleophiles. We propose that 2-ME can be used as a selective tumor biomarker in the course of certain types of lung cancers and possibly as a therapeutic adjuvant or neoadjuvant.

Increased risk of death compared to other antipsychotics in elderly clozapine users in Poland

Abstract: Clozapine can cause severe adverse effects. Few epidemiologic studies have considered the effect of clozapine use in elderly patients. The aim of this study was to assess mortality in elderly patients treated with clozapine in comparison to patients treated with first- or second-generation antipsychotics. We conducted a retrospective cohort study involving 26 639 patients who were 65 years of age or older and were receiving antipsychotic medication between 2008 and 2012. Cox proportional-hazards models were used to compare the risk of death between different groups of antipsychotics after controlling for age, sex, concomitant treatment with cardiovascular or metabolic medications. The use of antipsychotic medications other than clozapine was associated with a lower adjusted risk of death [hazard ratio, 0.89; 95% confidence interval (95% CI), 0.79-0.99]. The use of cardiac and antilipemic but not antidiabetic drugs was associated with a significantly lower risk of death in this population (hazard ratio, 0.88; 95% CI, 0.83-0.93; hazard ratio, 0.66; 95% CI, 0.58-0.75 and hazarad ratio, 1.09; 95% CI, 0.96-1.24, respectively). These results suggest that clozapine is associated with an increased risk of death in the elderly. Although the study was based on administrative records linkage, its results suggest that attention should be paid to patients taking antipsychotics.

Photonic sensor to detect rapid changes in CRP levels

Abstract: One of the most important biomarkers used to determine inflammation is C-reactive protein (CRP). Its level, when it is within the range that does not define inflammation, informs about the risk of cardiovascular events. If the norm is exceeded and inflammation is detected in the body, CRP level can increase 1000 times within a few hours. The type of infection can also be determined based on the level of elevated CRP. All this makes CRP a very important element of diagnostics. A sensor based on low coherence interference is presented. Preliminary studies have shown that its sensitivity is 5.65 μg/L and the measurement time is short, <10 min. The entire system is built of commercially available components, which allow production cost minimalization. In addition, the user-friendly operation allows it to be operated by unqualified people. Due to these features, our solution is a promising alternative to commercially used enzyme-linked immunosorbent assay, which needs trained personnel to perform time-consuming measurement procedures.