Surface Plasmon Polaritons Probed with Cold Atoms

Plasmonics - We report on an optical mirror for cold rubidium atoms based on a repulsive dipole potential created by means of a modified recordable digital versatile disc. Using the mirror, we have...     

Anti-Oxidative Effects of Melatonin Receptor Agonist and Omega-3 Polyunsaturated Fatty Acids in Neuronal SH-SY5Y Cells: Deciphering Synergic Effects on Anti-Depressant Mechanisms

Omega-3 polyunsaturated fatty acids (n-3 or omega-3 PUFAs) and melatonin receptor agonist ramelteon (RMT) both display antidepressant effects, while their cellular effects on anti-oxidative and neuroprotective mechanisms might be different. In this study, we aimed to decipher the individual and synergistic actions of n-3 PUFAs and RMT, as compared with the conventional antidepressant fluoxetine (FLX), in a cellular model of oxidative stress, which might play an important role in the pathophysiology of depression and associated disorders. We investigated the rescue and prevention effects of FLX, RMT, and n-3 PUFAs, e.g., eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), by using cell viability in SH-SY5Y cells under oxidative stress along with measurements of key cellular markers of oxidative stress, inflammatory, and neuroprotection. The results revealed that the RMT and EPA combination significantly increased the cell viability in a dose-dependent manner. RMT showed preventive effects, FLX and DHA possessed rescue effects, while EPA showed both rescue and preventive effects. We observed the dose-dependent activation and translocation of nuclear factor-κB to the nucleus augmented by the expressions of peroxisome proliferator activator receptor-gamma, tyrosine hydroxylase, c-Fos expression, and reactive oxygen species, implying that RMT and EPA combination reversed oxidative and neuroinflammatory pathophysiology and protected the neuronal cells from further damage. The results demonstrated that RMT and EPA synergistically provide effective neuroprotective, anti-oxidative/inflammatory effect against oxidative stress. Our study provides pre-clinical evidence to conduct future clinical trials of using n-3 PUFAs/RMT combination in depressive disorders.     

Lipase‐catalyzed enantioselective transesterification of prochiral 1‐((1,3‐dihydroxypropan‐2‐yloxy)methyl)‐5,6,7,8‐tetrahydroquinazoline‐2,4(1H,3H)‐dione in ionic liquids

The application of ionic liquids as solvents for transesterification of prochiral pirymidine acyclonucleoside using lipase (EC 3.1.1.3) Amano PS from Burkholderia cepacia (BCL) is reported. The effect of using medium reaction, acyl group donor, and temperature on the activity and enantioselectivity of BCL was studied. From the investigated ionic solvents, the hydrophobic ionic liquid [BMIM]PF₆] was the preferred medium for enzymatic reactions. However, the best result was obtained in the mixture [BMIM][PF₆]:TBME (1:1 v/v) at 50°C. Enzyme activity and selectivity in [BMIM][PF₆]:TBME (1:1 v/v) was slightly higher in than in conventional organic solvents (for example, TBME), and in this condition, good activity and enantioselectivity were associated with unique properties of ionic liquid such as hydrophobicity and high polarity. Independently of solvents, monester of (R)‐configuration was obtained in excess. Under optimal conditions, desymmetrization of the prochiral compound using different acyl donors was performed. If vinyl butyrate was used as the acylating agent, BCL completely selectively acylated enantiotopic hydroxyl groups.     

Enantiomeric trans β-aryl-δ-iodo-γ-lactones derived from 2,5-dimethylbenzaldehyde induce apoptosis in canine lymphoma cell lines by downregulation of anti-apoptotic Bcl-2 family members Bcl-xL and Bcl-2

For many years, studies focused on developing new natural or synthetic compounds with antineoplastic activity have attracted the attention of researchers. An interesting group of such compounds seem to be those with both lactone moiety and an aromatic ring which, in addition to antimicrobial or antiviral activity, also exhibit antitumor properties. The study shows antitumor activity of two enantiomeric trans isomers of 5-(1-iodoethyl)-4-(2′,5′-dimethylphenyl)dihydrofuran-2-one. Our aim was to determine their antitumor activity manifested as an ability to induce apoptosis in selected canine cancer cell lines as well as to evaluate differences in their strength depending on the configuration of their stereogenic centers. The enantiomers (+)-(4R,5S,6R)-1 and (?)-(4S,5R,6S)-2 were found to induce classical caspase-dependent apoptosis through downregulation of the expression of anti-apoptotic proteins Bcl-xL and Bcl-2. Although the mechanism of apoptosis induction was the same for both enantiomers, they differed in their strength, as stronger antineoplastic activity in vitro was exhibited by isomer (+)-(4R,5S,6R)-1.     

Induction of apoptosis in human glioma cell lines of various grades through the ROS-mediated mitochondrial pathway and caspase activation by <Emphasis Type="Italic">Rhaponticum carthamoides</Emphasis> transformed root extract

The placenta plays a major role in embryo-fetal defects and intrauterine growth retardation after maternal alcohol consumption. Our aims were to determine the oxidative status and cellular and molecular oxidative stress effects on uterine myometrium and trophoblast-decidual tissue following perigestational alcohol intake at early organogenesis. CF-1 female mice were administered with 10% alcohol in drinking water for 17 days prior to and up to day 10 of gestation. Control females received ethanol-free water. Treated mice had smaller implantation sites compared to controls (p < 0.05), diminished maternal vascular lumen, and irregular/discontinuous endothelium of decidual vessels. The trophoblast giant cell layer was disorganized and presented increased abnormal nuclear frequency. The myometrium of treated females had reduced nitrite content, increased superoxide dismutase activity, and reduced glutathione (GSH) content (p < 0.05). However, the trophoblast-decidual tissue of treated females had increased nitrite content (p < 0.05), increased GSH level (p < 0.001), increased thiobarbituric acid-reactive substance concentration (p < 0.001), higher 3-nitrotyrosine immunoreaction, and increased apoptotic index (p < 0.05) compared to controls. In summary, perigestational alcohol ingestion at organogenesis induced oxidative stress in the myometrium and trophoblast-decidual tissue, mainly affecting cells and macromolecules of trophoblast and decidual tissues around early organogenesis, in CF-1 mouse, and suggests that oxidative-induced abnormal early placental formation probably leads to risk of prematurity and fetal growth impairment at term.     

The genetic background of antibiotic resistance among clinical uropathogenic Escherichia coli strains

Molecular Biology Reports - The spreading mechanisms of antibiotic resistance are related to many bacterial and environment factors. The overuse of antibiotics is leading to an unceasing emergence...     

Identification of birch pollen species using FTIR spectroscopy

In this study, the morphology and chemical composition of pollen grains of six birch species (Betula utilis Doorenbos, B. dahurica, B. maximowicziana, B. pendula, B. pubescens and B. humilis) were examined to verify which of these features allow distinguishing them in a more unambiguous way. For this purpose, scanning electron microscopy and light microscopy, as well as Fourier transform infrared (FTIR) spectroscopy and curve-fitting analysis of amide I profile, were performed. The microscopy images show that the pollen grains of B. pubescens, B. pendula and B. humilis are similar in diameter and significantly smaller than those of others species, with the largest diameter observed for B. utilis Doorenbos. However, the results obtained from FTIR spectroscopy indicate that the chemical compositions of B. pubescens and B. pendula are similar, but B. humilis is outlaying. Summarizing, it is not possible to unambiguously state, which feature or which technique is the best for differentiating between the six chosen birch species. However, the study showed that both techniques have potential for identification of birch pollen species.