Development of stable marker-free nuclear transformation strategy in the green microalga Chlorella vulgaris

Although microalgae have valuable resources with great necessity in many biotechnological applications, no tools have been developed yet for a stable genetic transformation without antibiotic marker genes in these organisms. Chlorella is one of the most useful genus for biotechnological applications. The transfer of foreign DNA (vector or linear DNA cassette) into Chlorella by electroporation has very low stability and it is hard to screen the transformants without antibiotic marker genes. However, the marker genes have some disadvantages to host cells. To avoid the negative effects caused by the marker genes, we tried to develop a stable marker-free nuclear transformation system in Chlorella. For this, linear gene expression cassettes (LGEC) were constructed with functional domains, which are responsible for transformation, of SV40 large T antigen. The LGECs were transferred into Chlorella via electroporation and durability of the LGECs were confirmed in transgenic Chlorella. Transcription levels of the LGECs were also determined at different cell cycle sates. The LGECs integrated into the chromosomal DNA of Chlorella were stably replicated and were expressed successfully at G0-, G1-, and G2-phases. This study presents a stable marker-free nuclear transformation system with potential for biotechnological applications.Key words: Chlorella vulgaris, marker-free nuclear transformation, SV40 large T antigen, microalga

Polarized light propagation through scattering media: time-resolved Monte Carlo simulations and experiments

A study of polarized light transmitted through randomly scattering media of a polystyrene-microsphere solution is described. Temporal profiles of the Stokes vectors and the degree of polarization are measured experimentally and calculated theoretically based on a Monte Carlo technique. The experimental results match the theoretical results well, which demonstrates that the time-resolved Monte Carlo technique is a powerful tool that can contribute to the understanding of polarization propagation in biological tissue. Analysis based on the Stokes-Mueller formalism and the Mie theory shows that the first scattering event determines the major spatial patterns of the transmitted Stokes vectors. When an area detected at the output surface of a turbid medium is circularly symmetrical about the incident beam, the temporal profile of the transmitted light is independent of the incident polarization state. A linear relationship between the average order of the scatters and the light propagation time can be used to explain the exponential decay of the degree of polarization of transmitted light

Direct effects of caffeine on osteoblastic cells metabolism: the possible causal effect of caffeine on the formation of osteoporosis

BACKGROUND: Caffeine consumption has been reported to decrease bone mineral density (BMD), increase the risk of hip fracture, and negatively influence calcium retention. In this study, we investigated the influence of caffeine on the osteoblasts behaviour. METHOD: Osteoblasts derived from newborn Wistar-rat calvaria was used in this study. The effects of various concentrations of caffeine on bone cell activities were evaluated by using MTT assay. Alkaline phosphatase (ALP) staining, von Kossa staining and biochemical parameters including ALP, lactate dehydrogenase (LDH), prostaglandin E(2 )(PGE(2)) and total protein were performed at day 1, 3, and 7. DNA degradation analysis under the caffeine influence was also performed. RESULTS AND DISCUSSION: The results showed that the viability of the osteoblasts, the formation of ALP positive staining colonies and mineralization nodules formation in the osteoblasts cultures decreased significantly in the presence of 10 mM caffeine. The intracellular LDH, ALP and PGE(2 )content decreased significantly, the LDH and PGE(2 )secreted into the medium increased significantly. The activation of an irreversible commitment to cell death by caffeine was clearly demonstrated by DNA ladder staining. CONCLUSION: In summary, our results suggest that caffeine has potential deleterious effect on the osteoblasts viability, which may enhance the rate of osteoblasts apoptosis

Diazido­bis{2-[3-(dimethyl­amino)propyl­imino­meth­yl]phenol}manganese(III) perchlorate

The title compound, [Mn(N3)2(C12H18N2O)2]ClO4, was synthesized from manganese(III) acetate, sodium azide and 2-[3-(dimethyl­amino)propyl­imino­meth­yl]phenol by a hydro­thermal reaction. The MnIII ion is hexa­coordinated by two N and two O atoms from two phenolate ligands and two N atoms from two azide ligands. The MnIII cation lies on an inversion centre and, as a result, the asymmetric unit comprises one half-mol­ecule

Cathodic bacterial community structure applying the different co-substrates for reductive decolorization of Alizarin Yellow R

Selective enrichment of cathodic bacterial community was investigated during reductive decolorization of AYR fedding with glucose or acetate as co-substrates in biocathode. A clear distinction of phylotype structures were observed between glucose-fed and acetate-fed biocathodes. In glucose-fed biocathode, Citrobacter (29.2%), Enterococcus (14.7%) and Alkaliflexus (9.2%) were predominant, and while, in acetate-fed biocathode, Acinetobacter (17.8%) and Achromobacter (6.4%) were dominant. Some electroactive or reductive decolorization genera, like Pseudomonas, Delftia and Dechloromonas were commonly enriched. Both of the higher AYR decolorization rate (k(AYR) = 0.46) and p-phenylenediamine (PPD) generation rate (k(PPD) = 0.38) were obtained fed with glucose than acetate (k(AYR) = 0.18; k(PPD) = 0.16). The electrochemical behavior analysis represented a total resistance in glucose-fed condition was about 73.2% lower than acetate-fed condition. The different co-substrate types, resulted in alteration of structure, richness and composition of bacterial communities, which significantly impacted the performances and electrochemical behaviors during reductive decolorization of azo dyes in biocathode. (C) 2016 Elsevier Ltd. All rights reserved.11116Ysciescopu

Psyllium fiber improves hangovers and inflammatory liver injury by inhibiting intestinal drinking

Introduction: Excessive alcohol intake often results in hangovers and inflammatory liver damage, posing a significant health concern. Current treatment options for hangovers are still insufficient, highlighting the urgent need for new therapeutic approaches. Psyllium fiber (PF) is well-known for its gastrointestinal benefits, but its effect on hangovers is less explored.Methods: We utilized a mouse model with a single binge drinking (4 g/kg) to induce hangover and inflammatory liver injury. Intestine and liver injury were serologically and histologically estimated. Hangover symptoms were assessed using cylinder and footprint tests to objectively quantify hangover symptoms in mice.Results: Binge drinking significantly activated alcohol-metabolizing enzymes in the small intestine and liver, leading to inflammatory damage. Concurrently, there was a rise in alcohol metabolites such as acetaldehyde and acetone, which exhibited a positive correlation with hangover symptoms in mice. Interestingly, the oral administration of PF (100 mg/kg) alongside alcohol consumption significantly reduced the activity of these enzymes and lowered the levels of alcohol metabolites. Mice treated with PF exhibited a considerable improvement in hangover symptoms and a reduction in hepatic inflammation, compared to control groups. Furthermore, in vitro experiments using HepG2 cell lines and semipermeable membranes demonstrated that PF effectively inhibits alcohol absorption into the body.Discussion: In conclusion, PF demonstrates a potential protective effect against alcohol-induced hangover and liver injury by inhibiting the absorption of alcohol and lowering hangover-related alcohol metabolites. This study suggests that PF could serve as an effective therapeutic option for mitigating the adverse effects of excessive alcohol consumption