Establishment and characterization of Caspian horse fibroblast cell bank in Iran

Caspian horse, a rare horse breed found in 1965 by Louise Firouz in northern Iran, is a small horse which is reported to be in danger of extinction in its original homeland. There seems to be a great need to prevent extinction of this valuable horse. In this study, 51 fibroblast cell lines from Caspian horse ear marginal tissue were successfully established by sampling 60 horses using primary explant technique. Cells were authenticated and growth curve was plotted. According to results obtained, population doubling time (PDT) was calculated 23 ± 0.5 h for all cell lines. Multiplex polymerase chain reaction (multiplex PCR) revealed that cell lines had no cross-contamination with other species. Bacteria, fungi, and mycoplasma contamination were checked using standard methods such as PCR, direct culture, and Hoechst staining. In addition to providing a valuable source for genomic, postgenomic, and somatic cloning researches, the established cell lines would preserve Caspian horse genetic resources. It will also create an accessible database for researchers.     

Possible relation between a bloom of Distephanus speculum (Silicoflagellata) and anoxia in bottom waters in the Northern Adriatic, 1983

Silicoflagellates, rare planktonic algae, were registered inbloom-like conditions in the 20-m-deep bottom layer of the Gulfof Trieste, Northern Adriatic. The confusing taxonomy and ecologyof these phytoflagellates, as well as their possible contributionto the oxygen depletion of the bottom layer, is discussed.     

Quantitative performance metrics for robustness in circadian rhythms

MOTIVATION: Sensitivity analysis provides key measures that aid in unraveling the design principles responsible for the robust performance of biological networks. Such metrics allow researchers to investigate comprehensively model performance, to develop more realistic models, and to design informative experiments. However, sensitivity analysis of oscillatory systems focuses on period and amplitude characteristics, while biologically relevant effects on phase are neglected. RESULTS: Here, we introduce a novel set of phase-based sensitivity metrics for performance: period, phase, corrected phase and relative phase. Both state- and phase-based tools are applied to free-running Drosophila melanogaster and Mus musculus circadian models. Each metric produces unique sensitivity values used to rank parameters from least to most sensitive. Similarities among the resulting rank distributions strongly suggest a conservation of sensitivity with respect to parameter function and type. A consistent result, for instance, is that model performance of biological oscillators is more sensitive to global parameters than local (i.e. circadian specific) parameters. Discrepancies among these distributions highlight the individual metrics' definition of performance as specific parametric sensitivity values depend on the defined metric, or output. AVAILABILITY: An implementation of the algorithm in MATLAB (Mathworks, Inc.) is available from the authors. SUPPLEMENTARY INFORMATION: Supplementary Data are available at Bioinformatics online.     

Variation of nitrogenase activity, photosynthesis and pigmentation of the cyanobacterium Fischerella ambigua strain FS18 under different irradiance and pH values

Summary Our objective was to evaluate the physiological response of Fischerella ambigua FS18 to the combined influence of pH (5, 7 and 9) and light intensity (3 and 300 μmol photon m⁻² s⁻¹). Growth rates were similar at pH 9 and pH 7. There was no growth at pH 5. Increasing light intensity did not have any considerable influence on growth rates. Chlorophyll concentration was higher at pH 7 at all light intensities. Chlorophyll concentration decreased with increasing light intensity from 3 to 300 μmol photon m⁻² s⁻¹. Synthesis of the phycobiliproteins (PBP), phycocyanin (PC) and allophycocyanin (APC) had the highest rate in pH 7. Increasing irradiance decreased the concentrations of all PBPs. The light-saturated photosynthetic rate was clearly higher at high light intensity. With respect to nitrogenase activity, the highest rate was at pH 9 and 300 μmol photon m⁻² s⁻¹. Irradiance did not affect significantly this activity at pH 7. This cyanobacterium seems to be alkalophilic with maximum nitrogenase activity and photosynthesis at pH 9. It can also adapt its photosynthetic apparatus to the variable factors that are found in rice fields.     

Bioinspired multicolour carbon dots: comprehensive cytotoxicity,phytotoxicity, and bioimaging in animal cells and plants

During the past decades, carbon dots (CDs) as a kind of nanoparticles with interesting fluorescence properties have retained their place as one of the best bioimaging agents, although their effects on plants have been rarely studied. In this study, we synthesized two kinds of concentration-dependent multicolour CDs using two solvent approaches, phosphate-buffered saline (PBS) and ethanol 20%. We confirmed the nature of the CDs through Fourier transform infrared spectroscopy, atomic force microscopy, dynamic light scattering, zeta potential, X-ray powder diffraction, and high-resolution transmission electron microscopy. Afterwards, the cytotoxicity, phytotoxicity, and bioimaging of animal cells and plants using both synthesized CDs were examined. Eventually, PBS-based CDs were recommended during this study as an efficient bioimaging agent for animal cells and plants because of the appealing features of this CD, such as a small size range of less than 10 nm, surface charge with an average of −24 mV, a high quantum yield of 35.82%, the higher fluorescence intensity of ~400 a.u. for blue fluorescence light and 250 a.u. for green fluorescence light. Other features showing the superiority of PBS-based CDs include high photostability, low phytotoxicity (p ≤ 0.05 and p ≤ 0.01) and above all, there was no significant cytotoxicity at the concentration range of 500–7.81 μg/ml.     

Dinoflagellate Endosymbiont of the Soft Coral Stichodactyla haddoni Saville-Kent Collected from the Coast of Hormuz Island,Strait of Hormuz

Russian Journal of Marine Biology - An endosymbiotic dinoflagellate isolated from the soft coral Stichodactyla haddoni from the coast of Hormuz Island, Strait of Hormuz, Persian Gulf, has been...     

Molecular basis of the digestive functionality in developing Persian sturgeon (Acipenser persicus) larvae: additional clues for its phylogenetic status

Persian sturgeon (Acipenser persicus) is a critically endangered species, mainly due to overexploitation for its caviar. The permanence of populations of this species in the Caspian Sea is fully dependent on restocking programs. Accordingly, it is considered as an interesting target for aquaculture for both restocking and commercial purposes. In addition, as a Chondrostei, it exhibits one of the slowest rates of molecular evolution among vertebrates and is propounded as an excellent candidate for phylogenetic analysis and evolutionary biology. In this study, the early ontogeny of some key digestive enzymes precursors was determined at molecular level, aiming to obtain basic knowledge on the acquisition of digestive capacity of this species, and at the same time, to advance in its phylogenetic status from the point of view of digestion. For this purpose, A. persicus cDNAs for β-actin (actb; used as an internal reference gene), bile-salt activated lipase (cel), trypsinogen 1 (try1), pepsinogen (pga), and gastric proton pump (atp4a) were amplified and cloned, and their subsequent expressions were measured by quantitative real-time PCR during the first 34 days post hatch (dph). Two isoforms for pga and at least six for try1 were obtained in this study, probably due to the additional genome duplication which sturgeons suffered along evolution. Phylogenetic analysis of the deduced amino acids sequences from the studied genes demonstrated that this species has a close evolutionary distance to Holostei, coelacanths, and tetrapods, including amphibians, reptiles, birds and mammals. According to our results, expression of all the genes increased gradually over time and reached maximum levels around 18 dph. This pattern, which was comparable to length and weight data, could indicate that around 3 weeks after hatching, the digestive capacity of the Persian sturgeon changes from larval to juvenile mode.