Optimizing biodiesel production in marine Chlamydomonas sp. JSC4 through metabolic profiling and an innovative salinity-gradient strategy

BACKGROUND: Biodiesel production from marine microalgae has received much attention as microalgae can be cultivated on non-arable land without the use of potable water, and with the additional benefits of mitigating CO(2) emissions and yielding biomass. However, there is still a lack of effective operational strategies to promote lipid accumulation in marine microalgae, which are suitable for making biodiesel since they are mainly composed of saturated and monounsaturated fatty acids. Moreover, the regulatory mechanisms involved in lipid biosynthesis in microalgae under environmental stress are not well understood. RESULTS: In this work, the combined effects of salinity and nitrogen depletion stresses on lipid accumulation of a newly isolated marine microalga, Chlamydomonas sp. JSC4, were explored. Metabolic intermediates were profiled over time to observe transient changes during the lipid accumulation triggered by the combination of the two stresses. An innovative cultivation strategy (denoted salinity-gradient operation) was also employed to markedly improve the lipid accumulation and lipid quality of the microalga, which attained an optimal lipid productivity of 223.2 mg L(-1) d(-1) and a lipid content of 59.4% per dry cell weight. This performance is significantly higher than reported in most related studies. CONCLUSIONS: This work demonstrated the synergistic integration of biological and engineering technologies to develop a simple and effective strategy for the enhancement of oil production in marine microalgae

Enhancement of astaxanthin production in Xanthophyllomyces dendrorhous by efficient method for the complete deletion of genes

Additional file 1. DNA seuence of primers used in this study

Enlargement of the brachial plexus on magnetic resonance imaging: a novel finding in adult-onset Krabbe disease

Adult-onset Krabbe disease is an autosomal recessive degenerative leukodystrophy that presents with bilateral corticospinal tract involvement on MRI. Although peripheral nerve involvement is a known manifestation of Krabbe disease, MRI findings of peripheral nerve abnormalities are limited to the cranial nerves and spinal nerve roots. In this case report, we discuss two cases of adult-onset Krabbe disease with brachial plexus enlargement on MRI. Adult-onset Krabbe disease should be included in the differential diagnoses when brachial plexus enlargement and white matter lesions involving corticospinal tracts present simultaneously

In vitro generation of cytotoxic and regulatory T cells by fusions of human dendritic cells and hepatocellular carcinoma cells

<p>Abstract</p> <p>Background</p> <p>Human hepatocellular carcinoma (HCC) cells express WT1 and/or carcinoembryonic antigen (CEA) as potential targets for the induction of antitumor immunity. In this study, generation of cytotoxic T lymphocytes (CTL) and regulatory T cells (Treg) by fusions of dendritic cells (DCs) and HCC cells was examined.</p> <p>Methods</p> <p>HCC cells were fused to DCs either from healthy donors or the HCC patient and investigated whether supernatants derived from the HCC cell culture (HCCsp) influenced on the function of DCs/HCC fusion cells (FCs) and generation of CTL and Treg.</p> <p>Results</p> <p>FCs coexpressed the HCC cells-derived WT1 and CEA antigens and DCs-derived MHC class II and costimulatory molecules. In addition, FCs were effective in activating CD4⁺and CD8⁺T cells able to produce IFN-γ and inducing cytolysis of autologous tumor or semiallogeneic targets by a MHC class I-restricted mechanism. However, HCCsp induced functional impairment of DCs as demonstrated by the down-regulation of MHC class I and II, CD80, CD86, and CD83 molecules. Moreover, the HCCsp-exposed DCs failed to undergo full maturation upon stimulation with the Toll-like receptor 4 agonist penicillin-inactivated <it>Streptococcus pyogenes</it>. Interestingly, fusions of immature DCs generated in the presence of HCCsp and allogeneic HCC cells promoted the generation of CD4⁺CD25^highFoxp3⁺Treg and inhibited CTL induction in the presence of HCCsp. Importantly, up-regulation of MHC class II, CD80, and CD83 on DCs was observed in the patient with advanced HCC after vaccination with autologous FCs. In addition, the FCs induced WT1- and CEA-specific CTL that were able to produce high levels of IFN-γ.</p> <p>Conclusion</p> <p>The current study is one of the first demonstrating the induction of antigen-specific CTL and the generation of Treg by fusions of DCs and HCC cells. The local tumor-related factors may favor the generation of Treg through the inhibition of DCs maturation; however, fusion cell vaccination results in recovery of the DCs function and induction of antigen-specific CTL responses in vitro. The present study may shed new light about the mechanisms responsible for the generation of CTL and Treg by FCs.</p

Selective synthesis of carbon monoxide via formates in reverse water-gas shift reaction over alumina-supported gold catalyst

Thermal decomposition of formic acid on SiO2, CeO2 and gamma-Al2O3 was studied as an elementary step of reverse water-gas shit reaction (RWGS) over supported Au catalysts. gamma-Al2O3 showed the highest CO selectivity among the tested oxides in the decomposition of formic acid. Infrared spectroscopy showed the formation of four formate species on gamma-Al2O3: three eta(1)-type and one mu(2)-type species, and these formates decomposed to CO at 473 K or higher. Au-loaded gamma-Al2O3 samples were prepared by a deposition precipitation method and used as catalysts for RWGS. The supported Au catalyst gave CO with high selectivity over 99% from CO2 and H-2, which is attributed to the formation of formates on Au and subsequent decomposition to CO on gamma-Al2O3

Ruthenium-Immobilized Periodic Mesoporous Organosilica: Synthesis, Characterization, and Catalytic Application for Selective Oxidation of Alkanes

Periodic mesoporous organosilica (PMO) is a unique material that has a crystal-like wall structure with coordination sites for metal complexes. A Ru complex, [RuCl2(CO)(3)](2), is successfully immobilized onto 2,2'-bipyridine (BPy) units of PMO to form a single-site catalyst, which has been confirmed by various physicochemical analyses. Using NaClO as an oxidant, the Ru-immobilized PMO oxidizes the tertiary CH bonds of adamantane to the corresponding alcohols at 57 times faster than the secondary CH bonds, thereby exhibiting remarkably high regioselectivity. Moreover, the catalyst converts cis-decalin to cis-9-decalol in a 63% yield with complete retention of the substrate stereochemistry. The Ru catalyst can be separated by simple filtration and reused without loss of the original activity and selectivity for the oxidation reactions