Expression of aminopeptidase N (APN) on peripheral blood mononuclear cells' surface as a marker of these cells' transendothelial migration properties in the course of multiple sclerosis.

CD13 Ag and CD11a, CD11b, CD18 molecule expression on peripheral blood mononuclear cells (PBMC) were studied as these cells' adherent or transendothelial migration properties in three different multiple sclerosis (MS) patients groups (total 38): with clinically active MS (acute exacerbation of MS and primary chronic progressive MS (CP-MS)) and with MS remission. The control group consisted of patients, suffering from other non-inflammatory neurological diseases (OND). The results of our study suggest that CD11a/CD18 molecules expression on PB lymphocytes, although higher on these cells' surface in the course of MS as compared to OND, does not differentiate clinical forms of MS. CD11a molecule expression on monocytes did not differ significantly in all tested MS patient groups in comparison to OND. Although the expression of CD11b/CD18 molecules on monocytes' surface shows their activation in the course of MS, it does not differentiate them either. However, CD13 Ag of APN expression on PBMC surface may be an immunological marker of MS clinical form. CD13 Ag expression may also be a sensitive marker of these cells' transendothelial migration properties

The immunoregulatory abilities of polymorphonuclear neutrophils in the course of multiple sclerosis.

The polymorphonuclear neutrophils (PMN) possess sufficient potential to affect both immune response and inflammation, however it has not been yet described in the course of multiple sclerosis (MS). We have studied binding of fluorescein isothiocyanate (FITC)- stained TNF-alpha by PMN, the expression of CD11a, CD11b, and CD18 molecules of beta2-integrines and the expression of CD10 (neutral endopeptidase-NEP) and of CD13 (aminopeptidase N; APN) antigens on PMN in three different groups of MS patients. The control group included neurological patients (OND) with noninflammatory diseases. The obtained results have proved that during MS exacerbation and in the course of chronic progressive MS, PMN reveal several forms of preactivation, including significantly higher stained-TNF-alpha binding, higher expression of CD11b and CD18, as well as CD10 and CD13 antigens, in comparison with MS remission or OND. We suggest that the increased expression of these molecules on PMN of MS patients in exacerbation of the disease and to a lower degree in the course of CP-MS is a result of PMN priming, and directly prove the PMN involvement in the disease pathogenesis

Hydrostatic pressure study of paramagnetic-ferromagnetic phase transition in (Ga,Mn)As

The effect of hydrostatic pressure on the paramagnetic - ferromagnetic phase transition has been studied in (Ga,Mn)As. The variation of the Curie temperature (TC) with pressure was monitored by two transport methods: (1) - measurement of zero field resistivity versus temperature {\rho}(T), (2) - dependence on temperature of the Hall voltage hysteresis loop. Two specimens of different resistivity characteristics were examined. The measured pressure-induced changes of TC were relatively small (of the order of 1K/GPa) for both samples, however they were opposite for the two.Comment: 8 pages, 7 figure

The morphology and application of stem cells in digestive system surgery

Background: Stem cells constitute a group of cells which possess the ability to self-renew as well as the capacity to differentiate into a vast number of different cells within the human organism. Moreover, stem cells are able to undergo a potentially unlimited number of divisions and this characteristic is clinically essential. Specific fields of its application include treatment of diseases mainly in the field of haematology, orthopaedics, surgery, dentistry, and neurology. Materials and methods: In the following work, the current knowledge concerning mechanisms of stem cell treatment in different parts of the digestive system with its diseases as well as adjacent therapy for surgery has been revised. Results: Stem cells therapy may be used in the treatment of various diseases of different parts of the digestive system. This also applies to the end part of the digestive tract (proctological diseases) because stem cells can be used to treat fistulas. Liposuction allows more recovery of mesenchymal stem cells, compared to previous bone marrow harvesting methods. Despite the application of stem cells in the treatment of different diseases used for many years so far, the therapeutic use for the regeneration of the gastrointestinal tract is still rare and unfamiliar. Conclusions: Regenerative medicine seems to be a promising tool in medical research, especially when insulated cells and designed biomaterials are taken into consideration. Major points of discussion include types of stem cells, their origin or differentiation for the treatment of many diseases

Immunological aspects of the tumor microenvironment and epithelial-mesenchymal transition in gastric carcinogenesis

Infection with Helicobacter pylori, a Gram-negative, microaerophilic pathogen often results in gastric cancer in a subset of affected individuals. This explains why H. pylori is the only bacterium classified as a class I carcinogen by the World Health Organization. Several studies have pinpointed mechanisms by which H. pylori alters signaling pathways in the host cell to cause diseases. In this article, the authors have reviewed 234 studies conducted over a span of 18 years (2002–2020). The studies investigated the various mechanisms associated with gastric cancer induction. For the past 1.5 years, researchers have discovered new mechanisms contributing to gastric cancer linked to H. pylori etiology. Alongside alteration of the host signaling pathways using oncogenic CagA pathways, H. pylori induce DNA damage in the host and alter the methylation of DNA as a means of perturbing downstream signaling. Also, with H. pylori, several pathways in the host cell are activated, resulting in epithelial-to-mesenchymal transition (EMT), together with the induction of cell proliferation and survival. Studies have shown that H. pylori enhances gastric carcinogenesis via a multifactorial approach. What is intriguing is that most of the targeted mechanisms and pathways appear common with various forms of cancer

Experimental observation of defect pair separation triggering phase transitions

First-order phase transitions typically exhibit a significant hysteresis resulting for instance in boiling retardation and supercooling. The hysteresis arises, because nucleation of the new phase is activated. The free-energy change is positive until the nucleus reaches a critical size beyond which further growth is downhill. In practice, the barrier is often circumvented by the presence of heterogeneous nucleation centres, e. g. at vessel walls or seed crystals. Recently, it has been proposed that the homogeneous melting of ice proceeds via separation of defect pairs with a substantially smaller barrier as compared to the mere aggregation of defects. Here we report the observation of an analogous mechanism catalysing a two-dimensional homogeneous phase transition. A similar process is believed to occur in spin systems. This suggests that separation of defect pairs is a common trigger for phase transitions. Partially circumventing the activation barrier it reduces the hysteresis and may promote fluctuations within a temperature range increasing with decreasing dimensionality

Mechanisms of the Epithelial-Mesenchymal Transition and Tumor Microenvironment in Helicobacter pylori-Induced Gastric Cancer

Helicobacter pylori (H. pylori) is one of the most common human pathogens, affecting half of the world's population. Approximately 20% of the infected patients develop gastric ulcers or neoplastic changes in the gastric stroma. An infection also leads to the progression of epithelial-mesenchymal transition within gastric tissue, increasing the probability of gastric cancer development. This paper aims to review the role of H. pylori and its virulence factors in epithelial-mesenchymal transition associated with malignant transformation within the gastric stroma. The reviewed factors included: CagA (cytotoxin-associated gene A) along with induction of cancer stem-cell properties and interaction with YAP (Yes-associated protein pathway), tumor necrosis factor α-inducing protein, Lpp20 lipoprotein, Afadin protein, penicillin-binding protein 1A, microRNA-29a-3p, programmed cell death protein 4, lysosomal-associated protein transmembrane 4β, cancer-associated fibroblasts, heparin-binding epidermal growth factor (HB-EGF), matrix metalloproteinase-7 (MMP-7), and cancer stem cells (CSCs). The review summarizes the most recent findings, providing insight into potential molecular targets and new treatment strategies for gastric cancer

Effect of hydrostatic pressure on degradation of CdTe/CdMgTe heterostructures grown by molecular beam epitaxy on GaAs substrates

We have shown that external hydrostatic pressure leads to the creation of structural defects, mainly in the vicinity of the II-VI/GaAs interface in the CdTe/Cd{sub 1-x}Mg{sub x}Te heterostructures grown by the molecular beam epitaxy method on GaAs substrates. These defects propagating across the epilayer cause permanent damage to the samples from the point of view of their electrical properties. In contrast, photoluminescence spectra are only weakly influenced by pressure. Our results shed light on the degradation process observed even without pressure in II-VI-based heterostructures

Acoustic Phonon-Assisted Resonant Tunneling via Single Impurities

We perform the investigations of the resonant tunneling via impurities embedded in the AlAs barrier of a single GaAs/AlGaAs heterostructure. In the $I(V)$ characteristics measured at 30mK, the contribution of individual donors is resolved and the fingerprints of phonon assistance in the tunneling process are seen. The latter is confirmed by detailed analysis of the tunneling rates and the modeling of the resonant tunneling contribution to the current. Moreover, fluctuations of the local structure of the DOS (LDOS) and Fermi edge singularities are observed.Comment: accepted in Phys. Rev.