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Due to intrinsically low levels of antioxidant enzyme expression and activity, insulin producing pancreatic β-cells are particularly susceptible to free radical attack. In diabetes mellitus, which is accompanied by high levels of oxidative stress, this feature of β-cells significantly contributes to their damage and dysfunction. In light of the documented pro-survival effect of chemokine C-X-C Ligand 12 (CXCL12) on pancreatic β-cells, we examined its potential role in antioxidant protection. We report that CXCL12 overexpression enhanced the resistance of rat insulinoma (Rin-5F) and primary pancreatic islet cells to hydrogen peroxide (H2O2). CXCL12 lowered the levels of DNA damage and lipid peroxidation and preserved insulin expression. This effect was mediated through an increase in catalase (CAT) activity. By activating downstream p38, Akt and ERK kinases, CXCL12 facilitated Nrf2 nuclear translocation and enhanced its binding to the CAT gene promoter, inducing constitutive CAT expression and activity that was essential for protecting β-cells from H2O2.

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Poly [ADP‐ribose] polymerase 1 (PARP‐1) has an inhibitory effect on C‐X‐C motif chemokine 12 gene ( Cxcl12 ) transcription. We examined whether PARP‐1 affects the epigenetic control of Cxcl12 expression by changing its DNA methylation pattern. We observed increased expression of Cxcl12 in PARP‐1 knock‐out mouse embryonic fibroblasts (PARP1−/−) in comparison to wild‐type mouse embryonic fibroblasts (NIH3T3). In the Cxcl12 gene, a CpG island is present in the promoter, the 5′ untranslated region (5′ UTR), the first exon and in the first intron. The methylation state of Cxcl12 in each cell line was investigated by methylation‐specific PCR (MSP) and high resolution melting analysis (HRM). Both methods revealed strong demethylation in PARP1−/− compared to NIH3T3 cells in all four DNA regions. Increased expression of the Ten‐eleven translocation ( Tet ) genes in PARP1−/− cells indicated that TETs could be important factors in Cxcl12 demethylation in the absence of PARP‐1, accounting for its increased expression. Our results showed that PARP‐1 was a potential upstream player in (de)methylation events that modulated Cxcl12 expression.

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The aim of this work was to study the topography, morphology, vascularisation, histology and innervation of the lungs in the ground squirrel (Spermophilus citellus) and compare these data with those concerning the rat, mole rat, rabbit and mouse. The research was carried out on 15 animals. It was revealed that the right lung has four lobes (cranial, middle, caudal and accessory lobes), while the left lung is not divided into segments. The functional vessels are a. pulmonalis dextra et sinistra and vv. pulmonales (5-6), while the nutritive vessels of the lungs are a. bronchoesophagea dextra and v. bronchoesophagea dextra. Histological tissue sections of the lungs revealed that the wall of terminal bronchioles contains no cartilage and the mucosal epithelium is pseudostratified, cubic and ciliated. Clara cells (club cells, bronchiolar exocrine cells) are present but have no cilia. The lung alveolar diameter is 37 μm on average, and the thickness of the alveolar wall and the interalveolar septa is 1.38 μm. Destruction of the alveolar walls, accumulation of erythrocytes in the capillaries of alveolar septa and destruction of the cytolemma of the capillary endothelium were detected. In addition, connective tissue fibres and peripheral nerves were detected by silver impregnation.

Many river systems have been artificially modified for various reasons worldwide. Although simplified riverbeds due to artificial modifications often alter the species compositions and interactions, methods for mitigating habitat degradation in such rivers are underdeveloped. In this study, we evaluated the effects of tree branches on the survival of juvenile masu salmon Oncorhynchus masou under predation risk by piscivorous fish (White-spotted charr Salvelinus leucomaenis) in artificially simplified environments. We found that 0.4 m 2 or more of tree branches per 1.0 m 2 of artificial concrete pond doubled the survival of juvenile salmon for 20 days. In addition, body sizes of predator and prey did not have a significant effect on salmon survival, whereas the number of branches did in this experiment. These results indicate that adding structural complexity can mitigate predation pressure by piscivorous fish in artificially simplified environments. This study provides important guidelines for the management and restoration of suitable habitats for stream salmonids in artificially simplified environments where the main predators are piscivorous fish.

Three new 1D coordination polymers, [Pb 2 (CH 3 SO 3 ) 4 (H 2 O) 2 ] n , [Hg(CH 3 SO 3 ) 2 (H 2 O) 2 ] n and [Sr(CH 3 SO 3 ) 2 (H 2 O)] n , were synthesized as large single crystals. The crystals were analyzed and characterized by the means of X-ray analysis, IR and NMR spectroscopy, elemental analysis and solid state UV-Vis spectroscopy. The formation of 1D polymeric chains in the crystal structures of the title compounds is affected by the various bonding modes of the bridging methanesulfonate groups. The studied compounds showed no decomposition in the air.