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Discusses the active role H5, a linker histone, plays in the control of chromatin activity. A transfected H5 gene in rat sarcoma cells, which do not produce H5, showed an arrest of cell proliferation. The results also show H5 may play an active part in the control of DNA replication.

Using NiTi alloys with shape memory for long-term medical implants requires modification of their surface due to the possible occurrence of corrosion. Hence, the surface of the staples used to join fractured bone within the craniofacial region was modified by applying a titanium oxy-nitrogen layer and a hydroxyapatite coating. Surface-modified clamps were tested in vivo using New Zealand white rabbits. After determining the mechanical characteristics of the bone and considering the initial state and surface modification, the diameter of the wire (used to make the clamps with the appropriate compression force) was selected. Implantation was performed on two groups of rabbits: experimental and control. In the experimental group, an intentionally induced bone fracture was treated in one tibia. On the second tibia, two additional clamps were applied to increase the possibility of a negative impact of the NiTi alloy on a living organism. After 6 weeks of application, a proper joining of the broken bone fragments was stated. Whereas after twelve weeks, no negative impact of the clamp material on a living organism, i.e., a rabbit, was found. Hence, the clamp with the modified surface can connect bone fragments in humans as well as small and medium-sized animals, with an extended range of use up to 12 weeks.

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) may be related to the occurrence of complications, including graft-versus-host disease (GvHD) and infections. The pathogenesis of acute GvHD is connected with T lymphocytes, which identify alloantigens on host's antigen-presenting cells, activate production of interferon-gamma (IFN-gamma) and interleukin-2 (IL-2), and act on the immune effector cells and damage tissues and organs., Aim: The aim of the study was to investigate and distinguish serum concentration profiles of IFN-gamma and IL-2 within a 30-d period after allo-HSCT., Methods: We enrolled 62 patients, i.e. , 30 (48%) male and 32 (52%) female subjects [median age 49.5 (19-68) years], after allo-HSCT from siblings ( n = 12) or unrelated donors ( n = 50) due to acute myeloid leukemia with myeloablative conditioning ( n = 26; 42%) and with non-myeloablative conditioning ( n = 36; 58%). All patients were given standard immunosuppressive therapy with cyclosporin-A and methotrexate and pre-transplant antithymocyte globulin in the unrelated setting. Blood samples were collected pre-transplant before and after (on day -1) the conditioning therapy and on days +2,+4, +6, +10, +20, and +30 after allo-HSCT. Serum levels of IL-2 and IFN-gamma were determined using ELISA., Results: Patients were divided into four groups depending on the presence of acute GvHD and clinical manifestations of infection. Group I included patients with neither acute GvHD nor infections [ n = 15 (24%)], group II consisted of patients with infections without acute GvHD [ n = 17 (27%)], group III was comprised of patients with acute GvHD without infections [ n = 9 (15%)], and group IV included patients with both acute GvHD and infections [ n = 21 (34%)]. IFN-gamma concentrations were higher in Group II than in other groups on days +20 ( P = 0.014) and +30 ( P = 0.008). Post-hoc tests showed lower concentrations of IFN-gamma on day +30 in groups I ( P = 0.039) and IV ( P = 0.017) compared to group II. The levels of IL-2 were mostly undetectable., Conclusion: Serum levels of IFN-gamma following allo-HSCT progressively escalate. High serum levels of IFN-gamma are related to infectious complications rather than acute GvHD. Serum concentrations of IL-2 in most patients are undetectable., Competing Interests: Conflict-of-interest statement: All the authors declare no conflict of interest for this article., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Infertility is a significant problem of humanity. In vitro fertilisation is one of the most effective and frequently applied ART methods. The effectiveness IVF depends on the assessment and selection of gametes and embryo with the highest developmental potential. The subjective nature of morphological assessment of oocytes and embryos is still one of the main reasons for seeking effective and objective methods for assessing quality in automatic manner. The most promising methods to automatic classification of oocytes and embryos are based on image analysis aided by machine learning techniques. The special attention is paid on deep neural networks that can be used as classifiers solving the problem of automatic assessment of the oocytes/embryos., Methods: This paper deals with semantic segmentation of human oocyte images using deep neural networks in order to develop new version of the predefined neural networks. Deep semantic oocyte segmentation networks can be seen as medically oriented predefined networks understanding the content of the image. The research presented in the paper is focused on the performance comparison of different types of convolutional neural networks for semantic oocyte segmentation. In the case study, the merits and limitations of the selected deep neural networks are analysed., Results: 71 deep neural models were analysed. The best score was obtained for one of the variants of DeepLab-v3-ResNet-18 model, when the training accuracy (Acc) reached about 85% for training patterns and 79% for validation ones. The weighted intersection over union (wIoU) and global accuracy (gAcc) for test patterns were calculated, as well. The obtained values of these quality measures were 0,897 and 0.93, respectively., Conclusion: The obtained results prove that the proposed approach can be applied to create deep neural models for semantic oocyte segmentation with the high accuracy guaranteeing their usage as the predefined networks in other tasks.

Objectives: No experimental study has shown that the myocardium of a remotely preconditioned patient is more resistant to a standardized ischaemic/hypoxic insult., Methods: This was a single-centre randomized (1:1), double-blinded, sham-controlled, parallel-group study. Patients referred for elective coronary bypass surgery were allocated to either remote ischaemic preconditioning (3 cycles of 5-min ischaemia/5-min reperfusion of the right arm using a blood pressure cuff inflated to 200 mmHg) or sham intervention. One hundred and thirty-four patients were recruited, of whom 10 dropped out, and 4 were excluded from the per-protocol analysis. The right atrial trabecula harvested on cannulation for cardiopulmonary bypass was subjected to 60 min of simulated ischaemia and 120 min of reoxygenation in an isolated organ experiment. Postoperative troponin T release and haemodynamics were assessed in an in vivo study., Results: The atrial trabeculae obtained from remotely preconditioned patients recovered 41.9% (36.3-48.3) of the initial contraction force, whereas those from non-preconditioned patients recovered 45.9% (39.1-53.7) (P = 0.399). Overall, the content of cleaved poly (ADP ribose) polymerase in the right atrial muscle increased from 9.4% (6.0-13.5) to 19.1% (13.2-23.8) (P < 0.001) after 1 h of ischaemia and 2 h of reperfusion in vitro. The amount of activated Caspase 3 and the number of terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells also significantly increased. No difference was observed between the remotely preconditioned and sham-treated myocardium. In the in vivo trial, the area under the curve for postoperative concentration of troponin T over 72 h was 16.4 ng⋅h/ml (95% confidence interval 14.2-18.9) for the remote ischaemic preconditioning and 15.5 ng⋅h/ml (13.4-17.9) for the control group in the intention-to-treat analysis. This translated into an area under the curve ratio of 1.06 (0.86-1.30; P = 0.586)., Conclusions: Remote ischaemic preconditioning with 3 cycles of 5-min ischaemia/reperfusion of the upper limb before cardiac surgery does not make human myocardium more resistant to ischaemia/reperfusion injury., Clinical Trial Registration Number: NCT01994707., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Unsatisfactory pancreatic cancer treatment outcomes have prompted multiple avenues of research focused on identifying not only biomarkers of pancreatic adenocarcinoma progression but also potential prognostic survival factors in patients with pancreatic adenocarcinoma. Study consisted of 75 patients who underwent pancreatic resections between 2006 and 2011: 35 patients with pancreatic ductal adenocarcinoma (PC), 30 patients with chronic pancreatitis (CP), and a non-malignant control group (NMCG) of 10 patients who underwent surgery due to benign tumors. Tissue plasminogen activator (t-PA) concentrations in tissue homogenates and sera were evaluated. The mean t-PA concentration in PC tissue homogenates was 12.3 ± 2 (7.5, 15) ng/mg. Compared with the t-PA concentration in the PC group, lower concentrations of t-PA (3.3 ± 0.7 (2.2, 4.7) ng/mg and 5.9 ± 0.8 (4.6, 7.3) ng/mg (P < 0.01)) were observed in tissue homogenates of the CP and the NMCG patients, respectively. Although serum concentrations of t-PA did not differ between patient groups, in PC patients, the t-PA concentrations were higher in sera than in tissue homogenates. In contrast, the CP and NMCG patient groups had lower t-PA concentrations in sera compared with tissue homogenates. Increasing tissue homogenate t-PA concentrations were associated with blood vessels infiltration. Tissue homogenate and serum t-PA concentrations were not related to the survival rate of patients with PC. The t-PA concentration above 7.45 ng/ml in tissue homogenates was indicative of PC. We concluded that higher concentrations of t-PA were observed in pancreatic cancer tissue compared to chronic pancreatitis, suggesting its potential role in the development and progression of pancreatic cancer. In contrast, the lack of significant differences in the serum t-PA concentrations between treatment groups suggests that serum t-PA concentrations may not be suitable as a biomarker for the diagnosis of pancreatic cancer.

Background: Asthma is a chronic inflammatory disorder of the airways with the proven role of Th2 cells in its pathogenesis. The role and characteristic of different subsets of CD4(+) cells is much less known., Aim: The aim of the study was to analyze the incidence of different subsets of CD4(+) T cells, in particular different subsets of CD4(+) cells with the co-expression of different cytokines., Methods: Twenty five stable asthmatic and twelve age-matched control subjects were recruited to the study. Bronchoscopy and bronchoalveolar lavage (BAL) were performed in all study subjects. CD4(+) T cells were isolated from BAL fluid by positive magnetic selection. After stimulation simultaneous expression of TGF-β, FoxP3, CD25, IFN-γ, IL-4, TNF-α (set 1); IL-10, FoxP3, CD25, IFN-γ, IL-4, MIP-1β (set 2); IL-17A, IL-8, IFN-γ, IL-4, MIP-1β (set 3) were measured by flow cytometry., Results: The percentage of CD4(+) cells co-expressing Foxp3 and TGF-β (CD4(+)Foxp3(+)TGF-β(+) cells) was significantly lower (P = 0.03), whereas the percentage of CD4(+)IL-17(+) cells (P = 0.008), CD4(+)IL-17(+) IFN-γ(+) cells (P = 0.047) and CD4(+)IL-4(+) cells (P = 0.01) were significantly increased in asthmatics compared with that seen in healthy subjects. A significantly higher percentage of CD4(+)Foxp3(+) cells from asthma patients expressed IFN-γ (P = 0.01), IL-4 (P = 0.004) and CD25 (P = 0.04), whereas the percentage of CD4(+)IL-10(+) cells expressing Foxp3 was significantly decreased in asthmatics (P = 0.03). FEV1% predicted correlated negatively with the percentage of CD4(+)IL-17(+) cells (r = -0.33; P = 0.046) and positively with CD4(+)Foxp3(+)TGF-β(+) cells (r = 0.43; P = 0.01)., Conclusions: Our results suggest that in the airways of chronic asthma patients there is an imbalance between increased numbers of CD4(+)IL-17(+) cells and Th2 cells and decreased number of CD4(+)Foxp3(+)TGF-β(+).

Insomnia is a serious medical and social problem, its prevalence in the general population ranges from 9 to 35% depending on the country and assessment method. Often, patients are subject to inappropriate and therefore dangerous pharmacotherapies that include prolonged administration of hypnotic drugs, benzodiazepines and other GABAA receptor modulators. This usually does not lead to a satisfactory improvement in patients' clinical states and may cause lifelong drug dependence. Brain state transitions require the coordinated activity of numerous neuronal pathways and brain structures. It is thought that orexin-expressing neurons play a crucial role in this process. Due to their interaction with the sleep-wake-regulating neuronal population, they can activate vigilance-promoting regions and prevent unwanted sleep intrusions. Understanding the multiple orexin modulatory effects is crucial in the context of pathogenesis of insomnia and should lead to the development of novel treatments. An important step in this process was the synthesis of dual antagonists of orexin receptors. Crucially, these drugs, as opposed to benzodiazepines, do not change the sleep architecture and have limited side-effects. This new pharmacological approach might be the most appropriate to treat insomnia.

Background: Long-term treatment with gonadoliberin analogs is used to block the hypothalamic-pituitary-gonadal axis. The use of these agents is generally considered to be safe; however, some observations suggest the possibility of adverse effects., Material/methods: We investigated whether a 3-months administration of a low dose (6 µg/kg b.w.) of dalarelin - a new agonist, and cetrorelix - a known antagonist of GnRH to female rats causes morphological changes in pituitary gland, ovaries, uterus and liver (HE and VG staining); effects on pituitary, hepatic and blood enzyme activities (histochemical and kinetic methods, respectively), and on the blood lipid profile (colorimetric methods); and to what extent these changes are reversible., Results: Applying analogs effectively inhibited ovulation, affected the uterine endometrium and changed histological appearance of the liver (e.g., steatosis). They altered activities of marker enzymes of cellular respiration, gluconeogenesis and intracellular digestion in the liver and, partially in the pituitary gland, caused undesirable changes in the activities of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and creatine kinase, and a concentration of cholesterol HDL fraction and triglycerides in the blood. Both morphological and enzymatic effects were more evident after antagonist administration; changes in the blood lipid profile were more evident after agonist administration. In both analogs histological and enzymatic changes persisted a relatively long time after the discontinuation of the treatment., Conclusions: The low dose of dalarelin and cetrorelix is sufficient to cause limited damage of hepatic cells and may modify the function of pituitary, ovaries, uterus and liver as well as other organs, even after discontinuation of the treatment.

It has been established beyond doubt that, as well as the liver, the small intestine is an important site of first-pass metabolism of numerous drugs, food components and toxic xenobiotics. However, there is not much information available about age-dependent changes of intestinal biotransformation pathways. In the present paper, we evaluated the relationships between intestinal cytochrome P450 complex activity and the age of animals. The study was carried out on male Sprague-Dawley rats (n = 5) from 5 age series: 0.5-, 2-, 4-, 20-, and 28 months old. Animals at every age series were divided into 4 groups: control and three groups of rats treated with the CYP450 specific inducers: phenobarbital, β-naphtoflavone and dexamethasone, respectively. RNA was isolated from intestinal mucosa, and then standard RT-PCR was used for the analysis of CYP1A1, CYP2B1/2 and CYP3A1 mRNA expression. Additionally, the activities of NADPH-cytochrome P450 and NADH-cytochrome b(5) reductases in the microsomal fraction were biochemically estimated. The constitutive intestinal CYP1A1 mRNA expression changes during maturation and aging. Inducibility of CYP1A1 gene was evident in intestinal mucosa at 2-, 4- and 20-month-old rats. A similar pattern of changes was observed for CYP2B1/2 isoforms. CYP3A1 mRNA expression was not detected in small intestine of 2-week-old rats. In matured rats, constitutive intestinal CYP3A1 expression was low, although after induction, significant increases in CYP3A1 mRNA amount were noted in aged individuals. Intestinal activity of both analyzed reductases was lowest in immature rats and highest in 28-month-old animals. In conclusion, the activity of cytochrome P450 complex in rat small intestine was not decreased by the aging processes, so the high rate of oxidative metabolic reactions in intestinal mucosa can be maintained till the advanced life stage.

The presence of stem cells differentiating to hepatocytes and cholangiocytes has been previously reported in livers of young rats. Here, we have isolated, cultured, and characterized mesenchymal stem cells (MSCs) from livers of young and old rats and tested their multipotential for differentiation. The mesenchymal stem cells in liver sections were identified by the presence of markers, respectively for primary stem cells Thy-1 and CD34, for differentiation to early cholangiocytes GST and CK19, and for differentiation to hepatocytes GSTalpha and CK18. Ki67 was detected as the cell proliferation marker. Cells isolated from livers of either age group were tested in a culture for their viability following storage and were characterized for the presence of most of the markers detected in cells in situ. The results revealed age-dependent changes in the number of recovered primary MSCs. In both age groups we have observed cells changing under differentiating conditions to liver cell lineages, such as cholangiocytes and hepatocytes, as well as to non-liver cells such as adipocytes, astrocytes, neuroblasts, and osteoblasts. Our data revealed that from the livers of rats 20 months and older the primary MSCs could be isolated and expanded; however, they were significantly fewer, even though their differentiation multipotential was preserved. The mechanism involved in the differentiation of liver MSCs seemed to depend on a constellation of signals in Notch signalling pathways. Thus, our results support the idea of potential use of liver as a source of MSCs, not only for liver reconstruction but also for cell therapy in general.

The article reviews the possible responses of liver cells to chemical insult. Both the necrosis and different ways of apoptotic death are considered. The regulatory role of BCL2/BAX proteins, p53 protein as well as other proteins modulating its activity is also described. The controlled proliferation is presented which base on transition of fully differentiated hepatocytes from the resting Go phase to GI phase of cell cycle. It is triggered by the loss of organ mass after extensive necrosis induced by xenobiotics. In this context the interrelations between the parenchymal cells (hepatocytes) and nonparenchymal cells, intercellular matrix, released growth factors are discussed. Tumorigenesis is also mentioned with special emphasis on the cell cycle control points and "run-away" from apoptosis of some cells despite the serious mistakes present in their DNA.

The linker histones (H1, H5, H1 degrees) are involved in the condensation of chromatin into the 30-nanometer fiber. This supranucleosome organization correlates with the resting state of chromatin, and it is therefore possible that the linker histones play an active role in the control of chromatin activity. The effect of H5 has been directly determined by expression of an inducible transfected H5 gene in rat sarcoma cells, which do not produce H5. Transfection resulted in the reversible inhibition of DNA replication and arrest of cells in G1, at which time H5 concentrations approached that of terminally differentiated avian erythrocytes. The arrest of proliferation was accompanied by specific changes in gene expression probably related to the cell cycle block. The selectivity of these effects suggest that H5 plays an active role in the control of DNA replication and cell proliferation.

A nuclear DNA ligase activity from immature chicken erythrocytes, and to a lesser extent T4-induced DNA ligase, can join cohesive-ends (3 and 5-nucleotides long) having one of the mismatches, A/A, T/T, C/C, G/G, at the middle position. The rate of ligation depends on the length and stability of the mispaired intermediate (G/G, T/T greater than A/A, C/C). When the non-complementary overhanging-ends are short (i.e. 1-nucleotide) both ligases catalyze the joining of the single-stranded protruding-end with a blunt-end. This reaction occurs at low but significant rates compared to blunt-end ligation. The chicken ligase has lower flush-end joining activity than T4 DNA ligase, but it is more permissive since it joins C/C or A/A mismatched-ends, whereas the prokaryotic ligase does not. Possible biological implications of the reactions are discussed. We have also found that BstEII easily cleaves at sites harboring a C/C or a G/G mismatch at the center of its recognition sequence, whereas AvaII (T/T or A/A), HinfI (G/G) and DdeI (G/G) do not.