Asymmetric Synthesis of the Functionalized A/E-Ring Fragment of C18-Diterpenoid Alkaloids.

A new asymmetric synthesis of the A/E-ring fragment of C18-diterpenoid alkaloids is described. The crucial contiguous stereogenic centers at C4, C5, and C11 were established through an asymmetric Michael addition/allylation sequence. The unique azabicyclo[3.3.1]nonane motif (A/E rings) was assembled by employing ring-closing metathesis and Mitsunobu reaction as key strategies.

Ultra-trace detection and efficient adsorption removal of multiple water-soluble volatile organic compounds by fluorescent sensor array.

Due to the extremely low concentration, complex composition and easy to be converted into each other in water and air of water-soluble volatile organic compounds (VOCs), it is a great challenge to the traditional detection technology, pollution control and traceability, etc. Therefore, developing a convenient, swift and on-site detection method for simultaneous quantification of multiple VOCs is highly anticipated. In this paper, a multifunctional sensor array with adsorption and sensing of VOCs has been constructed by four fluorescence channels of small-sized Eu@Uio-66 and Tb@Uio-66. Due to the obvious cross-reactive characteristics between 4 fluorescence channels and VOCs, the sensor array could detect 8 VOCs simultaneously with all detection limits as low as ppb level. In addition, the detection results of sensor array for actual water samples coexisting with multiple VOCs confirmed that it has strong anti-interference performance and could be used for simultaneous detection of multiple VOCs in real water. The construction of sensor array with VOC adsorption function not only helps to reduce the detection limit of VOCs benefiting from the pre-concentration of materials, but also has significant value to reduce the harmfulness of pollutants. Predictably, this work is of great significance for VOC traceability, analysis of ecotoxicological effects and monitoring of pollution distribution characteristics.

Off-the-shelf GMP-grade UC-MSCs as therapeutic drugs for the amelioration of CCl4-induced acute-on-chronic liver failure in NOD-SCID mice.

BACKGROUND AND PURPOSE: Umbilical cord-derived mesenchymal stem/stromal cells (UC-MSCs) are advanced therapy medicinal products (ATMPs) and thus act as an alternative to liver transplantation for acute-on-chronic liver failure (ACLF). Therewith, we are aiming to evaluate the pharmacologyandpharmacokinetics of GMP-grade UC-MSCs products on carbon tetrachloride (CCl4)-induced ACLF mouse model and the concomitant therapeutic dose for intravenous administration. METHODS: For the purpose, the GMP-grade UC-MSCs products were transplanted intravenously into the aforementioned CCl4-induced ACLF NOD-SCID mouse model, and the therapeutic effect was evaluated with the aid of serological, biochemical and histological assessments. Meanwhile, the correlationshipbetween the treatment groups and other characteristics were determined by conducting principal component analysis (PCA). To further verify the spatio-temporal pharmacokinetics of UC-MSCs products on ACLF treatment, we took advantage of the bioluminescence imaging (BLI) technology with the dual-color fluorescence reporter construct (pLV-Fluc-eGFP). RESULTS: The biological characteristics of UC-MSCs products were in conformity with the International Society of Cell Therapy (ISCT) criteriaand the GMP requirements. ACLF mice with high dose of UC-MSCs treatment revealed significantly alleviated pathological manifestations with a dramatically improved survival rate, the alleviation of liver injury with reduced hepatic enzyme, inflammatory infiltration and inflammatory cytokines. Notably, UC-MSCs in ACLF mice displayed preferable homing and delayed attenuation in the damaged liver tissue. CONCLUSION: Collectively, our data indicated the feasibility of UC-MSC-based cytotherapy for ACLF model administration. Our findings have provided new references for pharmacologyandpharmacokinetics assessments, which will provide overwhelming evidence for pre-clinical study in vivo.

Film-based fluorescent sensor for visual monitoring and efficient removal of aniline in solutions and gas phase.

Aniline has attracted much concern for its long degradation half-life and huge toxicity to the environment and human beings. Therefore, the development of a multi-functional device for visual detection and efficient removal of aniline was highly anticipated. In our work, the small-size Eu@UiO-66(COOH) was obtained by post-synthesis modification (PSM), and then the film-based fluorescent sensor was prepared by crosslinking reaction. The films not only showed incredible mechanical stability and potential for large-scale preparation, but also have excellent fluorescence response to aniline in solutions and gas phase. As the concentration of aniline increased, the fluorescence of films gradually increased at 350 nm, while the fluorescence gradually quenching at 620 nm, and the detection limits (LOD) of aniline in water and air were 0.27 ppb and 0.086 ppb, respectively. In addition, the adsorption performance of the film for aniline has also been confirmed and the maximum adsorption capacity was 32.6 mg/g, which is a strong guarantee for the realization of ultra-trace detection and toxicity reduction of aniline. In summary, the multi-functional film sensor has been designed for ultra-trace detection and efficient removal of aniline in solutions and gas phase, and have significant value for pollutant treatment, ecological restoration and early prevention.

Identification and manipulation of active centers on perovskites to enhance catalysis of peroxymonosulfate for degradation of emerging pollutants in water.

Perovskites (the general formula of ABO3) with versatile substrates can serve as desirable catalysts to initiate advanced oxidation processes (AOPs) for environmental remediation. However, the knowledge regarding the active centers remains piecemeal and unclear, such as how the redox metal centers of B site, inert metals of A site, oxygen vacancies, and direct oxidation of catalysts govern the chemical degradation of aqueous pollutants. This study aimed to identify principal alternations in physicochemical and electrical properties of ABO3-based perovskites modified with partial/overall substitution at A/B sites and synthesized at different conditions. In order to probe varied catalytic activity of these catalysts, ofloxacin (OFX) was used as a model micro-pollutant. Results showed that the OFX degradation by activation of peroxymonosulfate (PMS) with LaFeO3 perovskite was favored by the Sr substitution at A site, Cu substitution at B site, and increasing calcination temperature. Evolution of 1O2, •OH and SO4•- have proven for efficient OFX oxidation, as evidenced by results from in-situ electron paramagnetic resonance (EPR) analyses and quenching tests. Specifically, the introduction of Sr at A site can facilitate PMS self-decomposition to produce more 1O2 due to the increased abundance of surface oxygen vacancies. In contrast, the Cu substitution at B site improved the surface oxygen vacancies, as well as the electrical conductivity, which can further accelerate •OH and SO4•- generation for the OFX degradation. This study provides deeper insights into the underlying mechanisms governing the catalytic activity of perovskites. These findings build a basis for better decontamination of hazardous environmental organic pollutants.

Label-free assessment of replicative senescence in mesenchymal stem cells by Raman microspectroscopy.

Here, Raman microspectroscopy was employed to assess replicative senescence of mesenchymal stem cells (MSC). A regular spectral change related to the cell senescence was found in the ratio of two peaks at 1157 cm(-1) and 1174 cm(-1), which are assigned to C-C, C-N stretching vibrations in proteins and C-H bending vibrations in tyrosine and phenylalanine, respectively. With the cell aging, the ratio I1157 / I1174 exhibited a monotonic decline and showed small standard deviations, so that it can statistically distinguish between cells having slight changes in terms of aging. We propose that I1157 / I1174 can act as a characteristic spectral signature for label-free assessment of MSC senescence.

Human mesenchymal stem cells possess different biological characteristics but do not change their therapeutic potential when cultured in serum free medium.

INTRODUCTION: Mesenchymal stem cells (MSCs) are widely investigated in clinical researches to treat various diseases. Classic culture medium for MSCs, even for clinical use, contains fetal bovine serum. The serum-containing medium (SCM) seems a major obstacle for MSCs-related therapies due to the risk of contamination of infectious pathogens. Some studies showed that MSCs could be expanded in serum free medium (SFM); however, whether SFM would change the biological characteristics and safety issues of MSCs has not been well answered. METHODS: Human umbilical cord mesenchymal stem cells (hUC-MSCs) were cultured in a chemical defined serum free medium. Growth, multipotency, surface antigen expression, telomerase, immunosuppressive ability, gene expression profile and genomic stability of hUC-MSCs cultured in SFM and SCM were analyzed and compared side by side. RESULTS: hUC-MSCs propagated more slowly and senesce ultimately in SFM. SFM-expanded hUC-MSCs were different from SCM-expanded hUC-MSCs in growth rate, telomerase, gene expression profile. However, SFM-expanded hUC-MSCs maintained multipotency and the profile of surface antigen which were used to define human MSCs. Both SFM- and SCM-expanded hUC-MSCs gained copy number variation (CNV) in long-term in vitro culture. CONCLUSION: hUC-MCSs could be expanded in SFM safely to obtain enough cells for clinical application, meeting the basic criteria for human mesenchymal stem cells. hUC-MSCs cultured in SFM were distinct from hUC-MSCs cultured in SCM, yet they remained therapeutic potentials for future regenerative medicine.

Integration of sparse Bayesian learning and random subspace for fMRI Multivariate Pattern Analysis.

Multivariate Pattern Analysis (MVPA) is frequently used to decode cognitive states from brain activities in fMRI study. Due to the discrepancy between sample and feature size, MVPA methods are suffered from the overfitting problem. This paper addresses this issue by introducing sparse modelling along with its advanced decoding method, Compressive Sensing (CS). As brain voxels have highly correlated in spatial domain, the prerequisite of CS methods are not well satisfied. We therefore propose a novel MVPA method to integrate linear Sparse Bayesian Learning (i.e. Bayesian Compressive Sensing) with random subspace method. Benefiting from the random subspace method, spatial correlation and feature-to-sample ratio are largely reduced. The experimental results from a real fMRI dataset demonstrate that our method has distinct prediction power compared to three other popular MVPA methods, and the detected relevant voxels are located in informative brain areas.

Linear Dynamic Sparse Modelling for functional MR imaging.

The reconstruction quality of a functional MRI sequence is determined by reconstruction algorithms as well as the information obtained from measurements. In this paper, we propose a Linear Dynamic Sparse Modelling method which is composed of measurement design and reconstruction processes to improve the image quality from both aspects. This method models an fMRI sequence as a linear dynamic sparse model which is based on a key assumption that variations of functional MR images are sparse over time in the wavelet domain. The Hierarchical Bayesian Kalman filter which follows the model is employed to implement the reconstruction process. To accomplish the measurement design process, we propose an Informative Measurement Design (IMD) method. The IMD method addresses the measurement design problem of selecting k feasible measurements such that the mutual information between the unknown image and measurements is maximised, where k is a given budget and the mutual information is extracted from the linear dynamic sparse model. The experimental results demonstrated that our proposed method succeeded in boosting the quality of functional MR images.

Genome sequence of the thermostable-agarase-producing marine bacterium Catenovulum agarivorans YM01(T), which reveals the presence of a series of agarase-encoding genes.

Marine bacterium Catenovulum agarivorans YM01(T) can produce highly thermostable agarases. The draft genome of YM01(T) is about 5.36 Mb and harbors approximately 4,913 genes, including 15 agarase (2 α-agarase and 13 ß-agarase)-encoding genes, which will provide references to functional characterization of various agarases from marine bacteria.

Myroides phaeus sp. nov., isolated from human saliva, and emended descriptions of the genus Myroides and the species Myroides profundi Zhang et al. 2009 and Myroides marinus Cho et al. 2011.

A novel bacterial strain, designated MY15T, was isolated from a saliva sample taken from a student during a teaching experiment in China. Phylogenetic analyses based on 16S rRNA gene sequences showed that the novel strain was most closely related to Myroides marinus JS-08T, Myroides odoratimimus LMG 4029T and Myroides profundi D25T with 96.5 %, 96.3 % and 96.1 % gene sequence similarities, respectively, demonstrating that the novel strain belonged to the genus Myroides. Strain MY15T formed pale yellow colonies that turned to brown on Luria-Bertani (LB) agar and that gave off a characteristic fruity odour. Cells were Gram-staining-negative, rod-shaped and non-motile. The new isolate contained menaquinone 6 (MK-6) as the major respiratory quinone and C15:0 iso (51.2 %), C17:0 iso 3-OH (12.9 %) and C13:0 iso (10.5 %) as the dominant fatty acids. The G+C content of the DNA was 34.3 mol%. On the basis of this study, based on a polyphasic taxonomic approach, strain MY15T (=DSM 23313T=LMG 25566T) represents a novel species of the genus Myroides, for which the name Myroides phaeus sp. nov. is proposed. Emended descriptions of the genus Myroides and of the species M. profundi and M. marinus are also given.

Huaishuia halophila gen. nov., sp. nov., isolated from coastal seawater.

A novel Gram-negative, non-motile bacterium, designated ZXM137(T), was isolated from seawater collected from a coastal region of Qingdao, China, during a massive green algae (Enteromorpha prolifera) bloom. Strain ZXM137(T) was strictly aerobic and did not accumulate poly-ß-hydroxybutyrate. Growth occurred with 0.5-11.0% (w/v) NaCl, at pH 6-9 (optimum of pH 7) and at 4-45 °C (optimum at 28 °C). It contained Q-10 as the predominant ubiquinone and the major polar lipids were phosphatidylglycerol, phospholipids, and an unidentified aminolipid and lipid. The major cellular fatty acids of strain ZXM137(T) were C(18:1)ω7c, C(18:1)ω6c and 11-methyl C(18:1)ω7c. The DNA G+C content was 60.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZXM137(T) formed a distinct evolutionary lineage within the Roseobacter group in the class Alphaproteobacteria. On the basis of phenotypic, chemotaxonomic and phylogenetic evidence, strain ZXM137(T) represents a novel species in a new genus, for which the name Huaishuia halophila gen. nov., sp. nov. is proposed; the type strain is ZXM137(T) (=CGMCC 1.8891(T)=LMG 24854(T)).

Algoriphagus faecimaris sp. nov., isolated from coastal sediment.

A Gram-negative, non-motile, non-sporulating bacterial strain, designated LYX05(T), was isolated from coastal sediment of Qingdao, China, on the coast of the Yellow Sea. Strain LYX05(T) was aerobic and heterotrophic. The strain grew optimally at 37 °C and pH 7.5 and in the presence of 2% (w/v) NaCl. Colonies were 1-2 mm in diameter, circular, reddish orange and shiny with entire edges on marine agar medium. Cells were rods (0.3-0.5 µm wide and 0.8-1.6 µm long). The dominant fatty acids were iso-C(15:0) (40.82%) and C(16:0) (10.45%). The DNA G+C content was 42.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LYX05(T) was phylogenetically related to the members of the genus Algoriphagus and the closest relative was Algoriphagus hitonicola 7-UAH(T) (95.8% 16S rRNA gene sequence similarity). On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain LYX05(T) was considered to represent a novel species of the genus Algoriphagus, for which the name Algoriphagus faecimaris sp. nov. is proposed. The type strain is LYX05(T) (=JCM 16561(T) =DSM 23095(T) =LMG 25474(T)).

Catenovulum agarivorans gen. nov., sp. nov., a peritrichously flagellated, chain-forming, agar-hydrolysing gammaproteobacterium from seawater.

A novel Gram-negative, strictly aerobic, agar-hydrolysing bacterium, designated YM01(T), was isolated from seawater samples collected from the Yellow Sea (coastal region of Qingdao, PR China). Cells were rod-shaped, peritrichously flagellated and formed long chains end-to-end. The isolate had an absolute requirement for Na(+) ions, but not seawater, for growth and grew optimally at about 28 °C, in 2% NaCl and at pH 8.0-9.0. The isolate could not be cultured in marine broth 2216, but grew well on marine agar 2216. YM01(T) was able to hydrolyse cellulose, starch, aesculin and Tween 80, but not egg yolk, gelatin, urea or casein. 16S rRNA gene sequence analysis demonstrated that this isolate was unique, showing only 88.4-91.0% sequence similarity to its closest neighbours, including members of the genera Glaciecola (88.4-91.0%), Alteromonas (88.7-89.6%), Aestuariibacter (89.3-90.4%), Salinimonas (89.0%), Bowmanella (90.1-90.3%) and Agarivorans (88.5-89.9%). Phylogenetic analyses demonstrated that strain YM01(T) formed a distinct clade closely related to species of the family Alteromonadaceae within the group of Alteromonas-like gammaproteobacteria. It contained menaquinone MK-7 as the predominant isoprenoid quinone and C(16:0) (38.3%), C(16:1)ω7c and/or iso-C(15:0) 2-OH (29.0%), C(18:1)ω7c (9.3%) and C(10:0) 3-OH (8.2%) as major cellular fatty acids. Phosphatidylethanolamine, phosphatidylglycerol and an aminophospholipid were the major phospholipid constituents. The DNA G+C content was 44.8 mol%. Based on its phenotypic, chemotaxonomic and phylogenetic distinctiveness, strain YM01(T) is considered to represent a novel species in a new genus in the Gammaproteobacteria, for which the name Catenovulum agarivorans gen. nov., sp. nov. is proposed; the type strain of Catenovulum agarivorans is YM01(T) (=CGMCC 1.10245(T) =DSM 23111(T) =JCM 16580(T)).

Roseicitreum antarcticum gen. nov., sp. nov., an aerobic bacteriochlorophyll a-containing alphaproteobacterium isolated from Antarctic sandy intertidal sediment.

A novel Gram-negative, non-motile bacterium, designated strain ZS2-28(T), was isolated from sandy intertidal sediment samples collected from the coastal regions of the Chinese Antarctic Zhongshan Station on the Larsemann Hills, Princess Elizabeth Land, East Antarctica. Strain ZS2-28(T) was obligately heterotrophic, strictly aerobic, psychrotolerant (growth occurred at 0-33 °C) and moderately halophilic (optimal growth in 7-8 % NaCl). A single major peak at 872-874 nm in the infrared absorption spectrum indicated the presence of bacteriochlorophyll a. Poly-ß-hydroxybutyrate accumulation and slime production were also detected. The predominant cellular fatty acid was C18:1ω7c, with C10:0 3-OH, C16:0, C17:0 cyclo, C19:0ω8c cyclo and summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH) present in smaller amounts. The respiratory quinone was Q-10. The main polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified aminolipid. The G+C content of the genomic DNA was 63.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZS2-28(T) formed a distinct evolutionary lineage within the clade containing members of the genera Roseibaca, Roseinatronobacter and Rhodobaca of the class Alphaproteobacteria. On the basis of its phylogenetic position, as well as its phenotypic and chemotaxonomic characteristics, strain ZS2-28(T) represents a novel species of a novel genus, for which the name Roseicitreum antarcticum gen. nov., sp. nov. is proposed. The type strain is ZS2-28(T) ( = CGMCC 1.8894(T)  = LMG 24863(T)).

Evaluation of suitable reference gene for real-time PCR in human umbilical cord mesenchymal stem cells with long-term in vitro expansion.

In real-time quantitative PCR, the accuracy of normalized data is highly dependent on the stability of the reference genes. However, reference gene expression in a given cell type or experimental condition can vary considerably. The goal of this study was to establish a reliable set of reference genes for real-time PCR studies using human umbilical cord mesenchymal stem cells with long-term in vitro expansion. The stability of ten potential reference genes was examined in human umbilical cord mesenchymal stem cells. We found that Ywhaz and Rpl13a, not beta-actin or Gapdh, were the most stably expressed of the internal control genes in different passages of human umbilical cord mesenchymal stem cells. Ywhaz and Rpl13a could be used as reference genes for relative gene quantification and normalization purposes in real-time PCR studies of human umbilical cord mesenchymal stem cells.

[Effects of top pruning on fruiting characters of Platycodon grandiflorum].

OBJECTIVE: To investigate the effects of top pruning on fruiting characters of Platycodon grandiflorum, and find the suitable stage, in which seed growth and development furtherly. METHOD: One-year old seedlings were chosen and planted in field. Plant height, branching number, fruit number per plant, 1000 grains weight were measured during growth and development period, respectively. RESULT: The treatment of top pruning postponed in turn the flowering date, lowered the plant heights and the fruit number per plant, increased the branching number and influenced significantly on 1000 grains weights. CONCLUSION: The suitable stage of top pruning for producing seeds was from June 20th to July 5th.

[The relations between dental fluorosis and economic status in Shuicheng, a fluorosis-endemic County in Guizhou province].

OBJECTIVE: To discuss the relations of dental fluorosis and the social economic status in fluorosis-stricken villages where drying the corn by burning coal was prevail. METHODS: A total of 6 fluorosis-endemic villages and one non-endemic village were involved in the study. The general fluorine intake and the concentrations of fluorine in corn, in the pupils' were tested. Dental fluorosis among the pupils was also examen. A individual interview or household questionnaire survey was conducted to probe the economic condition and staple food structure in 600 adults. RESULTS: The fluorosis prevalence was lower in the villages of transportation convenience, higher income, less coal-dried corn intake. There was a declining trend of dental fluorosis in the corresponding age groups (r: 0.912, 0.916; P < 0.05); There was no significant changes in age-specified dental fluorosis in the low income villages. The correlation (r) of corn fluorine concentration and student's age-specified dental fluorosis prevalence and disparity was 0.755 - 0.980 (P < 0.05) and 0.302 - 0.811; The urine fluorine concentrations were 0.811 and 0.915 (P < 0.05). It was assumed that there was a negative correlation between family cash income and the dental fluorosis. CONCLUSIONS: The corn fluorine concentration is closely related to age-specified dental fluorosis. With the economic improvement, taking less coal-burned corn is the one of major factors in reducing the of dental fluorosis in these areas.