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Oleaginous microalgae hold great promises for biofuel production. However, commercialization of microalgal biofuels remains impracticable due to the lack of suitable industrial strains with high growth rate and lipid productivity. Engineering of metabolic pathways is a potential strategy for the improvement of microalgal strains for the production of lipids and also value-added products in microalgae. Malonyl CoA-acyl carrier protein transacylase (MCAT) has been reported to be involved in fatty acid biosynthesis. Here, we identified a putative MCAT in the oleaginous marine microalga Nannochloropsis oceanica. NoMCAT overexpressing N. oceanica showed a higher growth rate and photosynthetic efficiency. The neutral lipid content of engineered lines showed a significant increase by up to 31% compared to wild type. Gas chromatography-mass spectrometry analysis revealed that NoMCAT overexpression significantly altered the fatty acid composition. The composition of eicosapentaenoic acid (C20:5), which is a polyunsaturated fatty acid necessary for animal nutrition, increased by 8%. These results demonstrate the role of MCAT in enhancing fatty acid biosynthesis and growth in microalgae, and also provide an insight into metabolic engineering of microalgae with high industrial potential.

Background The marine diatom, Phaeodactylum tricornutum, has become a model for studying lipid metabolism and its triacylglycerol (TAG) synthesis pathway makes it an ideal target for metabolic engineering to improve lipid productivity. However, the genetic background and metabolic networks of fatty acid biosynthesis in diatoms are not well understood. Glycerol-3-phosphate acyltransferase (GPAT) is the critical enzyme that catalyzes the first step of TAG formation. So far, characterization of GPAT in marine microalgae has not been reported, especially at the level of comprehensive sequence-structure and functional analysis. Results A GPAT was cloned from P. tricornutum and overexpressed in P. tricornutum. Volumes of oil bodies were produced and the neutral lipid content was increased by twofold determined by Nile red fluorescence staining. Fatty acid composition was analyzed by GC–MS, which showed significantly higher proportion of unsaturated fatty acids compared to wild type. Conclusion These results suggested that the identified GPAT could upregulate TAG biosynthesis in P. tricornutum. Moreover, this study offers insight into the lipid metabolism of diatoms and supports the role of microalgal strains for biofuels production.

To master the dynamic endemic status and influencing factors of schistosomiasis in Yunnan Province, so as to provide the evidence for making the control and prevention measures.Four villages of four schistosomiasis heavy endemic counties were selected as survey sites. Then, the serological screening and etiological tests were carried out in the residents, and the basic situations of the survey sites were investigated. The infection status of the livestock and relevant information of Oncomelania hupensis snails were surveyed. All the results were analyzed statistically.Totally 4310 residents were surveyed by the indirect hemagglutination assay with the examination rate of 79.68% and serum positive rate of 8.40%. The positive rate reached upwards 12.53% in Qiandian Village of Eryuan County. The serum positive rate of the female was higher than that of the male, and the positive rates of the 30 years and older age groups were higher than those of the other age groups. The serum positive rates of the peasants, migrant labourers and residents with the junior high school education level were higher. No positive feces were found. A total of 24 advanced cases were reported. No positive livestock and snails were found, and the average density of living snails was 0.023 3-0.056 6/0.1 m2.Right now, the schistosomiasis is at a low prevalence status in Yunnan Province, and the endemic situation has been effectively controlled.

Green tides have occurred in Qingdao coast in China for seven consecutive years from 2007 to 2013. To provide information on the genetic structure of these blooms, 210 free-floating green algae samples isolated from the green tide in Qingdao coast on June 19, 2013 were identified based on the ITS, rbcL and 5S sequence, and genetic diversity was investigated by microsatellite markers. According to ITS, rbcL and 5S sequence, all the 210 samples belonged to Ulva prolifera. Nei's genetic diversity and Shannon index estimated using eight microsatellite markers indicated that the genetic diversity of U. prolifera population within Qingdao's green bloom in 2013 was low. Taking into account previous reports about life history and physiology of U. prolifera, we proposed that the limited origin area of the free-floating biomass and asexual reproduction of U. prolifera might be responsible for the lower diversity of free floating U. prolifera.

To understand the condition of the construction and management of sanitary latrines, and assess the effect of disposal of the excrement in rural schistosomiasis endemic areas in Yunnan Province.Three villages with schistosomiasis endemic were selected from Eryuan County and 30 households per village were sampled randomly for the field survey. The stool samples were sampled and tested according to the national standard.Totally 90 latrines were surveyed. The popularity rates of sanitary latrines in Yongle, Qiandian and Xinzhuang villages were 83.19%, 83.12% and 81.63% respectively. In the 90 household latrines, only 32.22% located inside the courtyard, and 91.67% of sanitary latrines and 70.00% of non-sanitary latrines had integrated buildings. Maggots or pupae or adult flies were found in 33.33% of sanitary latrines and all of non-sanitary latrines with the average amounts of 1.05 and 3.40 per latrine respectively. The removal rate of fecal coliform, the sedimentation rate of parasitic eggs and the mortality rate of Ascaris eggs were 90.00%, 80.61% and 95.20% on average respectively. The qualified rate of the fecal coliform of the outlet of the sanitary latrines was 41.67%, and the qualified rate of the mortality rate of Ascaris eggs was 78.13%. No living schistosome eggs were found at the outlets of latrines. For the effect of non-hazardous treatment, there was a statistically significant difference between the sanitary latrines and non-sanitary latrines.The latrine improvement has a good effect on non-hazardous treatment of the excrement in Yunnan Province, but the construction, application and management of sanitary latrines still need to be strengthened.

The “Atama complex”, which consists of Alexandrium tamarense, A. fundyense, and A. catenella, is one of the most important groups within the dinoflagellate genus Alexandrium. Information of the biogeography of the Atama complex is limited in the Arctic Ocean. In the present study, we established 55 strains of the Atama complex by incubating ellipsoidal cysts collected from the Chukchi Sea. The vegetative cells are characterized by a prominent ventral pore, thereby fitting the description of A. tamarense morphotype. Large subunit (LSU) and/or internal transcribed spacer (ITS) region sequences of these strains were examined. Both sequences showed intragenomic polymorphism. The 708 bp of the LSU sequences from the strains differed from each other at 0–44 sites (0.0–6.2 %), and the ITS region sequences differed from one another at 0–28 sites (0.0–5.4 %). Phylogenetic analysis revealed that the Chukchi Sea strains were nested within Atama complex (Group I). Assessment of paralytic shellfish poisoning toxin production by four Chukchi Sea strains using high-performance liquid chromatography showed that total toxin per cell ranged from 9 to 41 fmol cell−1. The toxin profile of the four strains from the Chukchi Sea is conserved, with the major toxins being N-sulfocarbamoyl toxin (C2), saxitoxin, and gonyautoxin-4. Our results support that dispersal of the Atama complex (Group I) from the Bering Sea to the Chukchi Sea might have occurred.

To provide more information on the origin of the Ulva prolifera bloom in Qingdao sea area in China from 2007 to 2011, the diversity of green algae growing on the rafts of Porphyra yezoensis on the coast in Jiangsu Province was investigated based on ITS, rbcL and 5S sequences. Eighty-four of green algal samples from various sites and cruises in 2010 and 2011 were collected. According to ITS and rbcL sequences, samples from the rafts of P. yezoensis fell into four clades: Ulva linza-procera-prolifera (LPP) complex, Ulva flexuosa, Blidingia sp. and Urospora spp. However, based on the 5S rDNA, a more resolved DNA marker, only one of the 84 samples belonged to U. prolifera. Combined with the previous reports, it is likely that U. prolifera bloom in Qingdao sea area might consist of more than one origin, and Porphyra cultivation rafts might be one of the causes.

The study goal was to clarify the therapeutic effect and the absorbed dose of radionuclide phosphorus-32 for skin hemangiomas and the consequent risk of side effects in these patients. Phosphorus-32 is an β emitter and is used for skin hemangioma treatment. In comparison with the few Gy per minute of the linear accelerators, the dose rate of phosphorus-32 for hemangiomas is much

Preparation process of new 5XXX series aluminum alloys containing cerium-rich mischmetal wasintroduced .The effects of cerium-rich mischmetal on fracture morphology and mechanical properties of aluminium alloy were investigated in detail by scanning electronic microscope (SEM), and tensile test.The results show that alloys tensile strength and elongation with the increase of the content of mischmetal first increased, then down. When the mischmetal content is increased up to 0.30%, the tensile strength and elongation are 115 MPa and 25.9% respectively, meanwhile, the fractograph exhibited typical ductile dimple fracture pattern. Then the alloy performance is best. Mischmetal added into the alloy can improve the mechanical properties of materials, but too much mischmetal will induce the decrease in the material performance.Becase it may generate more the coarse Al11(Ce ,La)3particle.

Oleaginous microalgae have received a considerable attention as potential biofuel feedstock. However, lack of industry-suitable strain with lipid rich biomass limits its commercial applications. Targeted engineering of lipogenic pathways represents a promising strategy to enhance the efficacy of microalgal oil production. In this study, a type 2 diacylglycerol acyltransferase (DGAT), a rate-limiting enzyme in triacylglycerol (TAG) biosynthesis, was identified and overexpressed in heterokont oleaginous microalga Nannochloropsis oceanica for the first time. Overexpression of DGAT2 in Nannochloropsis increased the relative transcript abundance by 3.48-fold in engineered microalgae cells. TAG biosynthesis was subsequently accelerated by DGAT2 overexpression and neutral lipid content was significantly elevated by 69% in engineered microalgae. The fatty acid profile determined by GC-MS revealed that fatty acid composition was altered in engineered microalgae. Saturated fatty acids and polyunsaturated fatty acids were found to be increased whereas monounsaturated fatty acids content decreased. Furthermore, DGAT2 overexpression did not show negative impact on algal growth parameters. The present investigation showed that the identified DGAT2 would be a potential candidate for enhancing TAG biosynthesis and might facilitate the development of promising oleaginous strains with industrial potential.

In order to explore the potential of graphene (G) in removal of hazardous chemicals in waste water, chemically reduced graphene oxide was employed as the adsorbent and the adsorption characteristics of graphene toward acrylonitrile (AN), p-toluenesulfonic acid (p-TA), 1-naphthalenesulfonic acid (1-NA) and methyl blue (MB) were evaluated under laboratory conditions. The results showed that the organic chemicals with larger molecule size and more benzene rings possessed a higher adsorption speed and a higher maximum adsorption capacity on G. The maximum adsorption capacities of p-TA, 1-NA and MB on G are ∼1.43 g/g G, ∼1.46 g/g G and ∼1.52 g/g G at 30 °C, respectively, which are the highest values of p-TA, 1-NA or MB adsorption on different kinds of today's nanomaterials. Under the maximum adsorption capacity, the absorption quantity of MB on G was dependent on the initial concentration of MB, and higher temperature could facilitate the adsorption process. The G efficiency remains almost constant during the first five cycles of the adsorption–desorption process. In addition, the fluorescence spectra implied that the adsorption of MB on G was a π–π stacking adsorption process. In conclusion, the G could serve as a promising adsorbent for the removal of chemicals containing benzene rings in waste water.

In this paper, AL-Mg-Mn-RE series alloys are becamed object of study.They are prouced with pure alumimum, pure Mg,electrolytic Mn and mix rich Ce rare earth. The effect of rare earth content on the resistance of the Al-Mg-Mn-RE series alloys are investigated by using Anodic polarization curves, electrochemical impendance spectroscopy. The results showed that their corrosivity is influenced by RE content in aluminum alloys.NO.3.3 impedance of Al-Mg-Mn-RE alloys is larger in the Nyquist diagram and its corrosion current of alloy decreases obviously. Then corrosivity of alloy is the best and the RE content is 0.3%,When the RE content is higher or lower than it that corrosivity isn’t improved but descended.

The presence of Fe and harmful effects on mechanical properties of pure aluminum and aluminum alloys are introduced. Several purification methods are reviewed, but all of them are of definite limitations. It is effective that precipitation method, filtration method and centrifugal division method are integrated.

Karenia mikimotoi (Miyake & Kominami ex Oda) Hansen & Moestrup is associated with harmful algal blooms in temperate and subtropical zones of the world. The hemolytic substances produced by K. mikimotoi are thought to cause mortality in fishes and invertebrates. We evaluated the composition of the hemolytic toxin produced by K. mikimotoi cultured in the laboratory using thin-layer chromatography. In addition, we evaluated the effect of co-occuring algae (Prorocentrum donghaiense and Alexandrium tamarense) and the cladoceran grazer Moina mongolica on hemolytic toxin production in K. mikimotoi. The hemolytic toxins from K. mikimotoi were a mixture of 2 liposaccharides and 1 lipid. Waterborne clues from P. donghaiense and A. tamarense inhibited the growth of K. mikimotoi but increased the production of hemolytic toxins. Conversely, K. mikimotoi strongly inhibited the growth of caged P. donghaiense and A. tamarense. In addition, the ingestion of K. mikimotoi by M. mongolica induced the production of hemolytic toxins in K. mikimotoi. Taken together, our results suggest that the presence of other microalgae and grazers may be as important as environmental factors for controlling the production of hemolytic substances. K. mikimotoi secreted allelochemicals other than unstable fatty acids with hemolytic activity. The production of hemolytic toxins in dinoflagellates was not only dependent on resource availability, but also on the risk of predation. Hemolytic toxins likely play an important role as chemical deterrents secreted by K. mikimotoi.

Many mobility models have been proposed for the simulation of vehicular sensor network, however, the existing models seldom consider the sociological Aspects of vehicle movement. The paper firstly analyzed the social characteristic of mobility of the real vehicular traces and gained the conclusion that is short average distance, limited node degree and high cluster coefficient. Based on it, a mobility model based social network is proposed and turned into a simulation, which consists of growing and evolvement of social networks, geographical location mapping of vehicles and node dynamics. The simulation results proved that the model’s characteristic is similar to real trace.

Making a study of the design of a NC inserting PC open CNC system from the aspect of hardware and software, this paper adopted a programmable multi-axis controller (PMAC) to construct a hardware platform for the open CNC system on the mode of “PC + motion controller”. Introduction was made to a kind of way of implementation of the open CNC system. The developed system can satisfy the experimental requirements of the university’s numerical control laboratory and also be used to rebuild CNC systems.

With the frequent occurrence and negative impacts of harmful algal blooms (HABs) on coastal countries throughout the world, it is urgently needed to find ways to control HABs effectively. Vermiculite, montmorillonite, palygorskite, and kaolin were modified with a Gemini surfactant to explore a new algaecide for controlling HABs. The removal efficiency of the modified clay minerals was evaluated with Chattonella marina, a typical HAB alga in China. Gemini modified vermiculite (G-VER) exhibited the highest removal rate against C. marina. When the concentration of G-VER (21.1% Gemini) was 6.5 mg/L, the removal rate reached to 100%. Dispersed in sea water for 72 h, only 3% of Gemini was released from the G-VER, indicating that the modified clay minerals had good stability in sea water and caused low impacts in the aquatic environment. G-VER is considered a potential algaecide with high efficiency and environmental safety.

The patternless casting manufacturing (PCM) technique adopted two nozzles to spray the binder and the curing agent separately into the dry sand under the control of a computer. In the PCM technique, the resin content of sand mold is mostly determined the quality of the final casts. In this paper the content of the binder droplets in sand particles is analyzed in detail. Thus it provides the theoretical basis for these process parameters such as scanning speed, layer thickness and so on. The results of experiments well verify the analysis.

The effect of capsaicin/gelatin/acacia/NaCMC crosslinked mixture coated outside polyethylene (PE) films on rodent repellent was studied. The concentrations of capsaicin coated were 0.5%, 1.0% and 3.0%, respectively. Determination of the rodent repellent effect was performed using the weight of grain inside the PE coated bags and the bitten proportion of PE coated bags. The results showed that the PE coated films were significantly able to expel mice (P

Effects of toxic Alexandrium species on Prorocentrum donghaiense were studied in co-cultures and filtrates in order to shed some light on the competition between the co-occurring harmful algae. The three live cultures of Alexandrium tamarense and Alexandrium minutum negatively affected the growth of P. donghaiense, while only A. minutum was affected by P. donghaiense when they were in 1:3 ratio of cells. Each species was affected by the co-occurring algae as could be observed by microscopy. The allelopathic effects observed in co-culture did not correlate with the measured content of the intracellular PSP toxins but matched the observed hemolytic properties of the culture filtrates, suggesting that certain hemolytic substances other than PSP toxins are responsible for the allelopathic effect of Alexandrium. (C) 2010 Elsevier B.V. All rights reserved.

Chrysolaminarin, the primary polysaccharide reservoir in some marine algae, has attracted much attention due to its broad health properties. However, its biosynthetic pathway and regulation mechanisms have rarely been reported which hinders the improvement of production efficiency. Therefore, this study aims to identify key metabolic nodes in the chrysolaminarin biosynthetic pathway. A phosphoglucomutase (PGM) in the model microalga Phaeodactylum tricornutum, revealing its critical role in chrysolaminarin biosynthesis is identified. PGM overexpression significantly elevates chrysolaminarin content by 2.54-fold and reaches 25.6% of cell dry weight; while algal growth and photosynthesis are not impaired. Besides, PGM overexpression up- and down-regulates the expression of chrysolaminarin and lipid biosynthetic genes, respectively. Microscopic analysis of aniline blue stained cells reveals that overproduced chrysolaminarin localized predominantly in vacuoles. Lipidomic analyses reveal that PGM overexpression significantly reduces the lipid content. The findings reveal the critical role of PGM in regulating the carbon flux between carbohydrate and lipid biosynthesis in microalgae, and provide a promising candidate for high efficiency production of chrysolaminarin.

In this paper, hypersensitive transitions of Nd( I) in Nd( I )-β-diketone-neutra] ligand ternary coordination compounds (where p-diketone = acetylacetone (AA), benzoylacetone (BA), dibenzoylmethane (DBM), 2-thenoyl trifluoroacetone (TTA); neutral ligand = pyridine (Py). cr.a′-dipyridyl (Dipy), phenanthroline (Phen) are studied and their intensities are given through dynamic coupling model. The results are in agreement with those observed and calculated using Judd-Ofelt equation. It may be seen that the dynamic coupling mechanism provides major contribution to the intensity of hypersensitive transition. On the other hand, in order to get the intensity of 4I9/14G5/2 transition, the absorption spectra in 560–610 nm have been decomposed into three peaks by nonlinear fitting with Lorentzian and Gaussian function and the “pure” intensities of hypersensitive transitions have been obtained, which are agreeable to those computed by Judd-Ofelt method and dynamic coupling model.

Hypersensitivity of the ternary complexes Ln(β-dik)4HMQ(where Ln=Nd, Ho, Er, β-dik=acetylacetonate(AA), dibenzoylmethanate(DBM) and MQ=4-methylquinoline) in acetone solution is studied based on the dynamic coupling model. The structures of these complexes in solution are deduced. Their coordination polyhydrons are all distorted square antiprism. Neodymium complexes have D2 symmetry, while holmium and erbium complexes have exact D2d symmetry.

We investigated the allelopathic properties of Alexandrium tamarense (Laboar) Balech on the growth of Prorocentrum donghaiense Lu, Chattonella marina (Subrahmanyan) Hara et Chihara and Heterosigma akashiwo (Hada) Hada in a laboratory experiment. We examined the growth of A. tamarense, C. marina, P. donghaiense and H. Akashiwo in co-cultures and the effect of filtrates from A. tamarense cultures in various growth phases, on the three harmful algal bloom (HAB)-forming algae. In co-cultures with A. tamarense, both C. marina and H. akashiwo were dramatically suppressed at high cell densities; in contrast, the growth of P. donghaiense varied in different inoculative ratios of A. tamarense and P. donghaiense. When the ratio was 1:1 (P. donghaiense: A. tamarense), growth of P. donghaiense was inhibited considerably, while the growth of P. donghaiense was almost the same as that of the control when the ratio was 9:1. The growth difference of P. donghaiense, C. marina and H. akashiwo when co-cultured with A. tamarense indicated that the allelopathic effect may be one of the important factors in algal competition and phytoplankton succession involving A. tamarense. In addition, the filtrate from A. tamarense culture had negative impacts on these three HAB algae, and such inhibition varied with different growth phases of A. tamarense in parallel with reported values of PSP toxin content in Alexandrium cells. This implied that PSP toxin was possibly involved in allelopathy of A. tamarense. However, the rapid decomposition and inactivation of PSP toxin above pH 7 weakened this possibility. Further studies on the allelochemicals responsible for the allelopathy of A. tamarense need to be carried out in future.

Automatic gauge control is an essentially nonlinear process varying with time delay, and stochastically varying input and process noise always influence the target gauge control accuracy. To improve the control capability of feedforward automatic gauge control, Kalman filter was employed to filter the noise signal transferred from one stand to another. The linearized matrix that the Kalman filter algorithm needed was concluded; thus, the feedforward automatic gauge control architecture was dynamically optimized. The theoretical analyses and simulation show that the proposed algorithm is reasonable and effective.

P-glycoprotein (P-gp or ABCB1) belongs to the family of ATP-binding cassette (ABC) transporters responsible for multixenobiotic resistance (MXR) in aquatic organisms. To provide more information of P-gp in shellfish, in this study, complete cDNA of P-gp in three bivalve species including Ruditapes philippinarum, Scapharca subcrenata and Tegillarca granosa were cloned and its expressions in gill, digestive gland, adductor muscle and mantle of the three bivalves were detected after exposure to Prorocentrum lima, a toxogenic dinoflagellate. The complete sequences of R. philippinarum, S. subcrenata and T. granosa P-gp showed high homology with MDR/P-gp/ABCB proteins from other species, having a typical sequence organization as full transporters from the ABCB family. Phylogenetic analyses revealed that the amino acid sequences of P-gp from S. subcrenata and T. granosa had a closest relationship, forming an independent branch, then grouping into the other branch with Mytilus californianus, Mytilus galloprovincialis and Crassostrea gigas. However, P-gp sequences from R. philippinarum were more similar to the homologs from the more distantly related Aplysia californica than to homologs from S. subcrenata and T. granosa, suggesting that bivalves P-gp might have different paralogs. P-glycoprotein expressed in all detected tissues but there were large differences between them. After exposure to P. lima, the expression of P-gp changed in the four tissues in varying degrees within the same species and between different species, but the changes in mRNA and protein level were not always synchronous.

The effects of five natural products from Chinese herbs including evodiamine, curcumin, 4-methoxysalicylaldehyde, esculin hydrate, and gramine on the growth of Chattonella marina, one of the most noxious red tide algae, were observed. Among them, gramine exhibited the highest inhibitory rate with LC50, 96h of 0.51 mg/l. After exposure to gramine, the activities of superoxide dismutase (SOD) and catalase (CAT), and content of malondialdehyde (MDA) increased in C. marina, suggesting that gramine could induce microalgae oxidative stress. In addition, chlorophyll a and the maximum quantum yield of photosynthesis (Fv/Fm) decreased following exposure to gramine, indicating the inhibition of photosynthesis activity in the microalgae. Combined with the fast inhibition against the algal cells and environmentally friendly character of gramine, we proposed that gramine might be a potential algaecide against marine harmful algae and that the oxidative damage and photosynthesis inhibition might be responsible for the toxicity of gramine on harmful algae.

Phosphorus (P) is an essential macronutrient for the survival of marine phytoplankton. In the present study, phytoplankton response to phosphorus limitation was studied by proteomic profiling in diatom Phaeodactylum tricornutum in both cellular and molecular levels. A total of 42 non-redundant proteins were identified, among which 8 proteins were found to be upregulated and 34 proteins were downregulated. The results also showed that the proteins associated with inorganic phosphate uptake were downregulated, whereas the proteins involved in organic phosphorus uptake such as alkaline phosphatase were upregulated. The proteins involved in metabolic responses such as protein degradation, lipid accumulation and photorespiration were upregulated whereas energy metabolism, photosynthesis, amino acid and nucleic acid metabolism tend to be downregulated. Overall our results showed the changes in protein levels of P. tricornutum during phosphorus stress. This study preludes for understanding the role of phosphorous in marine biogeochemical cycles and phytoplankton response to phosphorous scarcity in ocean. It also provides insight into the succession of phytoplankton community, providing scientific basis for elucidating the mechanism of algal blooms.

The rats were fed with water dissolved Y 3+ at different levels (0, 53.4, 5340 mg·L −1 ) for 7 months. The gene expression in brain tissue was detected with oligonucleotide microarray. The results show that, compared to the control, 789 genes express differentially, 507 over-expressed genes and 282 under-expressed genes in the high-dose group (5340 mg·L −1 ), of which, most were related to cell receptor, cell signal and transmission, and ionic passage. 44 genes were found to express differentially including 32 over-expressed genes and 12 under-expressed genes in the low-dose group (53. 40 mg·L −1 ), of which, most were related to cell skeleton and movement, immunity, and DNA binding protein. These results suggest that Y 3+ can change the expression of some genes, which may be responsible for the toxicity of rare earths on learning and memory.

Phaeocystis globosa Scherffel, an organism that causes harmful algal blooms, is a genus of the family Prymnesiophyta (or Haptophyta) with eurythermal and euryhaline characteristics. P. globosa has been confirmed to produce hemolytic substances, which are a mixture of liposaccharides. In the present study, the hemolytic properties of extract of P. globosa are analyzed further. The effects of temperature, pH, different divalent cations, and membrane lipids on extract-induced hemolysis are discussed, as is the possible hemolytic mechanism. The results of the present study showed that the hemolytic activity of the extract was approximately 127.1 hemolytic units (HU)/L. The hemolytic reaction became fastest and a 50% decrease in absorbance was induced at 30 min at 37 °C, and at pH 7.0; Hg2+ was the strongest inhibitor of the hemolysis compared with the other divalent cations and many membrane lipids, except for phosphatidic acid, inhibited the hemolytic activity to different degrees. These results suggest that the toxin may make pores in the surface of red blood cells and that Hg2+ either combines with the hemolysin or closes the pores, hence inhibiting its further hemolytic reaction. The toxin probably has no specific membrane receptor in the red blood cell membrane. (Managing editor: Ya-QinHAN)

Oxygen-free nanosized InN was synthesized by pulse discharge. NH3/N2 mixture and bulk indium were used as nitrogen source and discharge cathode, respectively. Optical emission spectra show that N2 and NH3 were highly dissociated in the discharge and oxygen could be eliminated effectively. A comparison was made between samples produced in the discharge of N2, NH3 and N2/NH3, respectively. XPS was used to determine the composition of the synthesized materials. Only In-N was produced when N2/NH3 was used as the discharge gas, whereas indium oxide was found in the case using N2 or NH3 as the discharge gas. The size of the produced InN was between 5 and 200 nm. A broad band with a blue shift of 150 nm from that of bulk InN was detected in the photoluminescence of the produced nanosized InN.

Microalgae are important primary producers in the marine ecosystem and excellent sources of lipids and other bioactive compounds. The marine diatom Phaeodactylum tricornutum accumulates eicosapentaenoic acid (EPA, 20:5n-3) as its major component of fatty acids. To improve the EPA production, delta 5 desaturase, which plays a role in EPA biosynthetic pathway, was characterized in P. tricornutum. An annotated delta 5 desaturase PtD5b gene was cloned and overexpressed in P. tricornutum. The transgene was integrated into the genome demonstrated by Southern blot, and the overexpression of PtD5b was verified by qPCR and Western blot analysis. Fatty acid composition exhibited a significant increase in the unsaturated fatty acids. Monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) showed an increase of 75% and 64%, respectively. In particular, EPA showed an increase of 58% in engineered microalgae. Meanwhile, neutral lipid content showed an increase up to 65% in engineered microalgae. More importantly, engineered cells showed a similar growth rate with the wild type, thus keeping high biomass productivity. This work provides an effective way to improve the production of microalgal value-added bioproducts by metabolic engineering.

Microalgae are ideal raw materials for biodiesel and bioactive compounds. Glycerol-3-phosphate is formed from dihydroxyacetone phosphate (DHAP) through the glycolytic pathway catalyzed by glycerol-3-phosphate dehydrogenase (GPDH). GPDH was characterized in the marine diatom Phaeodactylum tricornutum. In the GPDH-overexpressing P. tricornutum cells, the glycerol concentration per cell in the transformed diatom increased by 6.8-fold compared with the wild type, indicating that the overexpression of GPDH promoted the conversion of DHAP to glycerol-3-phosphate. There was a 60% increase in neutral lipid content, reaching 39.7% of dry cell weight in transgenic cells in the stationary phase, despite a 20% decrease in cell concentration. Fatty acid profiling showed that the levels of 16- and 18-carbon monounsaturated fatty acids significantly increased. GPDH had a significant impact on numerous metabolic processes in diatom cells, including the biosynthesis of glycerol and neutral lipids. These findings are instructive for the metabolic engineering of microalgae for biofuel production.

Background Microalgae have been an emerging biofuel resource; however, the germplasm improvement has been slow due to the lack of molecular tools. Pyruvate dehydrogenase kinase (PDK) deactivates the pyruvate dehydrogenase complex (PDC) which catalyzes the oxidative decarboxylation of pyruvate. Acetyl-CoA production via PDC is important in plant tissues that are active in fatty acid synthesis. Results A 1261-bp cDNA of a putative PDK gene (PtPDK) was cloned from a diatom Phaeodactylum tricornutum, and PtPDK antisense knockdown transgenic diatoms were generated. Both PtPDK transcript abundance and enzyme activity were reduced significantly due to antisense knockdown of PtPDK. Neutral lipid content of transgenic diatom cells increased up to 82% as determined by Nile red staining, and fatty acid composition was not altered. Transgenic cells showed slightly lower growth rate but similar cell size with the wild type, hence retaining similar biomass productivity. Conclusions This work first obtained a successful engineered diatom regulating a key gene involved in lipid metabolism. Our findings also provide powerful indications in enhancing microalgal lipid production by metabolic engineering for biofuel industry.

To obtain fast growing oil-rich microalgal strains has been urgently demanded for microalgal biofuel. Malic enzyme (ME), which is involved in pyruvate metabolism and carbon fixation, was first characterized in microalgae here. Overexpression of Phaeodactylum tricornutum ME (PtME) significantly enhanced the expression of PtME and its enzymatic activity in transgenic P. tricornutum. The total lipid content in transgenic cells markedly increased by 2.5-fold and reached a record 57.8% of dry cell weight with a similar growth rate to wild type, thus keeping a high biomass. The neutral lipid content was further increased by 31% under nitrogen-deprivation treatment, still 66% higher than that of wild type. Transgenic microalgae cells exhibited obvious morphological changes, as the cells were shorter and thicker and contained larger oil bodies. Immuno-electron microscopy targeted PtME to the mitochondrion. This study markedly increased the oil content in microalgae, suggesting a new route for developing ideal microalgal strains for industrial biodiesel production.

Bivalves naturally exposed to toxic algae have mechanisms to prevent from harmful effects of diarrhetic shellfish poisoning (DSP) toxins. However, quite few studies have examined the mechanisms associated, and the information currently available is still insufficient. Multixenobiotic resistance (MXR) is ubiquitous in aquatic invertebrates and plays an important role in defense against xenobiotics. Here, to explore the roles of P-glycoprotein (P-gp) in the DSP toxins resistance in shellfish, complete cDNA of P-gp gene in the mussel Perna viridis was cloned and analyzed. The accumulation of okadaic acid (OA), a main component of DSP toxins, MXR activity and expression of P-gp in gills of P. viridis were detected after exposure to Prorocentrum lima, a dinoflagellate producing DSP toxins in the presence or absence of P-gp inhibitors PGP-4008, verapamil (VER) and cyclosporin A (CsA). The mussel P. viridis P-gp closely matches MDR/P-gp/ABCB protein from various organisms, having a typical sequence organization as full transporters from the ABCB family. After exposure to P. lima, OA accumulation, MXR activity and P-gp expression significantly increased in gills of P. viridis. The addition of P-gp-specific inhibitors PGP-4008 and VER decreased MXR activity induced by P. lima, but had no effect on the OA accumulation in gills of P. viridis. However, CsA, a broad-spectrum inhibitor of ABC transporter not only decreased MXR activity, but also increased OA accumulation in gills of P. viridis. Together with the ubiquitous presence of other ABC transporters such as MRP/ABCC in bivalves and potential compensatory mechanism in P-gp and MRP-mediated resistance, we speculated that besides P-gp, other ABC transporters, especially MRP might be involved in the resistance mechanisms to DSP toxins.

Okadaic acid (OA), a main component of diarrheic shellfish poisoning (DSP) toxins, is a strong and specific inhibitor of the serine/threonine protein phosphatases PP1 and PP2A. However, not all of the OA-induced effects can be explained by this phosphatase inhibition, and controversial results on OA are increasing. To provide clues on potential mechanisms of OA other than phosphatase inhibition, here, acute toxicity of OA was evaluated in zebrafish, and changes in gene expression in zebrafish liver tissues upon exposure to OA were observed by microarray. The i.p. ED50 (6 h) of OA on zebrafish was 1.54 mu g OA/g body weight (bw). Among the genes analyzed on the zebrafish array, 55 genes were significantly up-regulated and 36 down-regulated in the fish liver tissue upon exposure to 0.176 mu g OA/g bw (low-dose group, LD) compared with the low ethanol control (LE). However, there were no obvious functional clusters for them. On the contrary, fish exposure to 1.760 mu g OA/g bw (high-dose group, HD) yielded a great number of differential expressed genes (700 up and 285 down) compared with high ethanol control (HE), which clustered in several functional terms such as p53 signaling pathway, Wnt signaling pathway, glutathione metabolism and protein processing in endoplasmic reticulum, etc. These genes were involved in protein phosphatase activity, translation factor activity, heat shock protein binding, as well as transmembrane transporter activity. Our findings may give some useful information on the pathways of OA-induced injury in fish. (C) 2014 Elsevier B.V. All rights reserved.

A diamond film was nitridated by low-energy nitrogen ion implantation. Raman spectrum shows β-C3N4 phase was formed in the nitridated diamond surface. Carbon nitride film was grown on this nitridated diamond surface by nitrogen-arc-discharge-assisted laser ablation deposition. The structure of the synthesized film was characterized by Raman spectroscopy. A series of narrow Raman peaks were observed in the range of 150–1550 cm−1. These peaks match well with the calculated Raman frequencies of β-C3N4, revealing the formation of the β-C3N4 phase.

11C-PD153035, a potent and specific ATP-competitive tyrosine kinase inhibitor (TKI) of the EGF receptor, has been developed for PET imaging of epidermal growth factor receptor (EGFR) in lung cancer. The objective of the present study was to investigate the relationship of the accumulation of 11C-PD153035 and the EGFR expression level in human gliomas and to explore whether 11C-PD153035 can be used in the molecular imaging of glioma with EGFR overexpression. Eleven patients with histopathologically proven gliomas underwent 11C-PD153035 PET/CT examination before surgery. Combining MRI with the 11C-PD153035 PET/CT image, 2 specimens from different C-PD153035 uptake regions of each tumor and adjacent normal brain tissue were selected as the biopsy targets through the stereotactic technique. The radioactivity concentrations were analyzed as the mathematical maximum standardized uptake value (SUVmax) in region of interest (ROI). The EGFR expression in the biopsied tissues was analyzed by immunohistochemical staining (IHC) and western blotting. The SUVmax/WM (11C-PD153035 uptake in the white matter of the contralateral normal hemisphere) ratio was used to indicate the EGFR expression level in the ROI in PET/CT, and it was correlated with the EGFR expression detected by IHC and western blot analysis. The results demonstrated that 6 of the 8 patients with glioblastoma (GBM) were obviously visualized by 11C-PD153035 PET/CT, whereas 2 patients with GBM, 1 with anaplastic astrocytoma, and 2 with oligodendroglioma did not show significant 11C-PD153035 uptake. There were positive correlations between the SUVmax/WM and the results of IHC (r = 0.955, P < 0.01) and western blotting(r = 0.889, P < 0.010). Our preliminary findings suggest that 11C-PD153035 PET/CT is a promising method for the EGFR-targeted molecular imaging of human GBM, which may be translated into the clinic to select the appropriate population of patients for EGFR-targeted therapy and to assess the early targeted therapeutic response of malignant gliomas.

To explore the value of video-electroencephalography plus surface electromyography (VEEG+SEMG) in providing theoretic rationales for clinical diagnosis of different motor seizure types and differentiating the application value of paroxysmal diseases.A total of 116 suspected and repetitive motion epileptics underwent VEEG+SEMG from 2009 to 2012. According to their clinical features, different muscles were selected to record electromyography (EMG) under different activations and stimulations (bodily movement and posture activation, touching, sound stimulus, tapping tendons and arms straight test, etc) and monitor their seizure states.Among 68 patients, 567 attacks were recorded, including 443 epileptic seizures in 41 patients (229 epileptic mycological seizures in 22 patients, 95 tonic seizures in 8, 118 epileptic spasms in 10 and 1 atonic seizure in 1). The average durations of different epileptic motor seizures were (0.16 ± 0.04), (2.9 ± 2.4), (1.4 ± 0.8) and 2 s respectively. Their features of ictal EEG and SEMG varied.Non-epileptic seizures were recorded, including 43 non-epileptic myoclonus (NEMS) in 2 patients 81 PKD in 25. The primary differential diagnoses of epileptic motor seizures were NEMS and paroxysmal kinesigenic dyskinesia (PKD).VEEG+SEMG is a reliable tool for diagnosing different types of epileptic seizures and differentiating among paroxysmal diseases.

Atomic nitrogen plays an important role in the synthesis of nitrides. In order to generate atomic nitrogen effectively under a low gas pressure, the pulsed discharges of the mixtures of NH3/N2, CH4/N2 or H2/N2 have been studied. The emission spectra show that nitrogen molecules were highly dissociated when adding a certain amount of ammonia or methane into nitrogen gas under a total pressure of 0.8 kPa, which is entirely different from the discharge of pure nitrogen gas. The optimal ratio of NH3/N2 for obtaining the highest yield of atomic nitrogen is about 1/9. The excitation temperature and the electron density of the discharge plasma were estimated to be 3300 K and of the order of 1016 cm-3, respectively.

UHP, a mild and selective oxidizing reagent, has been used to synthesis of octopus polysulfoxide in solid phase reaction under supersonic wave irradiation at room temperature with a high yield. Novel octopus polysulfoxide 2 has been synthesized by selective oxidation of octopus thioehter 1 in ≥95% yield using this method.

Both intensity of mitral regurgitant murmur and color-coded Doppler regurgitant signal area have been reported to correlate with the degree of regurgitation. To evaluate the relationship between the intensity of regurgitant murmur and severity of mitral regurgitation, phonocardiography, echocardiography, and Doppler ultrasound were performed in 18 patients with mitral regurgitation before and during dobutamine infusion. Mitral regurgitation was due to mitral valve prolapse with ruptured chordae tendineae in 8 patients, rheumatic change in 5 patients, and dilated cardiomyopathy in 5 patients. With intravenous dobutamine infusion, heart rate (77-103 beats/min), systolic blood pressure (119-144 mmHg), peak mitral regurgitant jet velocity (4.5-5.4 m/sec), intensity of mitral regurgitant murmur (to 201% of that before infusion in early systole) increased, while left ventricular end-diastolic volume (124-102 mm), left ventricular end-systolic volume (57-42 mm), mitral anular diameter (33-28 mm), and color Doppler mitral regurgitant signal area (704-416 mm(2)) decreased (P < 0.05). Total (forward + backward) left ventricular stroke volume (66-61 mL/beat) showed no change. Dobutamine decreased mitral regurgitant flow/beat, regardless of etiology of mitral regurgitation, which was probably due to the decrease of left ventricular size and mitral annular diameter. Although total (forward + backward) left ventricular stroke volume was unchanged, dobutamine effectively increased forward left ventricular stroke volume by decreasing backward regurgitation. Mitral regurgitant murmur became louder despite the decrease of mitral regurgation, indicating the uselessness of auscultation in the grading of the severity of mitral regurgitation.

Complexation of neodymium(III)–glutamate(glu)–phenanthroline(phen), neodymium(III)–aspartate(asp)–phenamhroline(phen) ternary systems and the corresponding binary systems in aqueous solution are discussed at various values of pH. Based on change regularity of hypersensitive transition intensities, the neodymium(III)–aspartate–phenanthroline ternary complex has a general formula of Nd(asp)3phen, but the composition of the complex of Nd(III) with glutamate and phenanthroline is complicated and has not been determined. The electronic spectra of these complexes were studied, Slater-Condon parameters Fks and the Lande parameter ξ 4f were obtained. The rms deviation between calculated and observed energy levels is less than 43 cm−1. Bonding in these complexes are also investigated and bonding parameters calculated. The results show that Nd(III) and amino acids form complexes by ionic linkage with carboxylic oxygens, but with some weak covalency. Besides, the degrees of covalency in ternary complexes are larger than those in binary complexes.

Background Nitrogen limitation can induce neutral lipid accumulation in microalgae, as well as inhibiting their growth. Therefore, to obtain cultures with both high biomass and high lipid contents, and explore the lipid accumulation mechanisms, we implemented nitrogen deprivation in a model diatom Phaeodactylum tricornutum at late exponential phase. Results Neutral lipid contents per cell subsequently increased 2.4-fold, both the number and total volume of oil bodies increased markedly, and cell density rose slightly. Transcriptional profile analyzed by RNA-Seq showed that expression levels of 1213 genes (including key carbon fixation, TCA cycle, glycerolipid metabolism and nitrogen assimilation genes) increased, with a false discovery rate cut-off of 0.001, under N deprivation. However, most light harvesting complex genes were down-regulated, extensive degradation of chloroplast membranes was observed under an electron microscope, and photosynthetic efficiency declined. Further identification of lipid classes showed that levels of MGDG and DGDG, the main lipid components of chloroplast membranes, dramatically decreased and triacylglycerol (TAG) levels significantly rose, indicating that intracellular membrane remodeling substantially contributed to the neutral lipid accumulation. Conclusions Our findings shed light on the molecular mechanisms of neutral lipid accumulation and the key genes involved in lipid metabolism in diatoms. They also provide indications of possible strategies for improving microalgal biodiesel production.

To explore the methods and applications of intraoperative magnetic resonance imaging (iMRI)-guided functional neuronavigation plus intraoperative neurophysiological monitoring (IONM) for microsurgical resection of lesions involving hand motor area.A total of 16 patients with brain lesions adjacent to hand motor area were recruited from January 2011 to April 2012. All of them underwent neuronavigator-assisted microsurgery. Also IONM was conducted to further map hand motor area and epileptogenic focus. High-field iMRI was employed to update the anatomical and functional imaging date and verify the extent of lesion resection.Brain shifting during the functional neuronavigation was corrected by iMRI in 5 patients. Finally, total lesion resection was achieved in 13 cases and subtotal resection in 3 cases. At Months 3-12 post-operation, hand motor function improved (n = 10) or remained unchanged (n = 6). None of them had persistent neurological deficit. The postoperative seizure improvement achieved Enge II level or above in 9 cases of brain lesions complicated with secondary epilepsy.Intraoperative MRI, functional neuronavigation and neurophysiological monitoring technique are complementary in microsurgery of brain lesions involving hand motor area. Combined use of these techniques can obtain precise location of lesions and hand motor functional structures and allow a maximum resection of lesion and minimization of postoperative neurological deficits.