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Gilvimarinus sp. DA14, a putative new species isolated from mangrove sediment in the South China Sea (Beihai, Guangxi province), is an aerobic and heterotrophic agar degrading bacterium. Here, we present the complete genome sequence of strain DA14, which comprises 3.96 Mb sequences with 53.39% GC content. In total, 3391 CDSs, 6 rRNA genes and 44 tRNA genes were obtained. Genomic analysis of strain DA14 revealed that 218 CAZymes classes were identified and they were organized in 371 CAZymes in PULs involved in polysaccharides degradation, transport and regulation. Further, we performed the genome comparison among Gilvimarinus strains and analysis the diversity of CAZymes and PULs. Meanwhile, ability of agar and alginate degradation in strain DA14 were analyzed. This study represents a thorough genomic characterization of CAZymes repertoire of Gilvimarinus, provides insight into diversity of polysaccharide degrading enzymes existing in Gilvimarinus sp. DA14 and their biotechnological applications.

BACKGROUND: Severe sepsis/septic shock with severe neutropenia often leads to poor prognosis. However, it is unknown if severe neutropenia is associated with different clinical outcomes and biomarker features in severe sepsis/septic patients. METHODS: This retrospective cohort study enrolled 141 severe sepsis/septic shock patients admitted to intensive care unit of Shanghai Children’s Medical Center between January 2015 and November 2019. Patients were followed up for the development of ventilation support, the use of vasoactive drugs, continuous renal replacement therapy (CRRT) procedure, and mortality. Biomarkers that reflect the level of inflammation in severe sepsis/septic shock patients with neutropenia were compared to that in patients without neutropenia. RESULTS: Of 141 patients enrolled, 54 patients suffered from severe sepsis/septic shock with severe neutropenia. In patients with severe sepsis/septic shock, severe neutropenia as a complication was an independent risk factor for the use of vasoactive drugs (RR 9.796; 95% CI: 3.774, 25.429; P

A novel moderately thermophilic, anaerobic, heterotrophic bacterium (strain SY095T) was isolated from a hydrothermal vent chimney located on the Southwest Indian Ridge at a depth of 2730 m. Cells were Gram-stain-positive, motile, straight to slightly curved rods forming terminal endospores. SY095T was grown at 45–60 °C (optimum 50–55 °C), pH 6.0–7.5 (optimum 7.0), and in a salinity of 1–4.5 % (w/v) NaCl (optimum 2.5 %). Substrates utilized by SY095T included fructose, glucose, maltose, N-acetyl glucosamine and tryptone. Casamino acid and amino acids (glutamate, glutamine, lysine, methionine, serine and histidine) were also utilized. The main end products from glucose fermentation were acetate, H2 and CO2. Elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and Fe(III) were not used as terminal electron acceptors. The predominant cellular fatty acids were C14 : 0 (60.5%) and C16 : 0 (7.6 %). The main polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. No respiratory quinones were detected. The chromosomal DNA G+C content was 30.8 mol%. The results of phylogenetic analysis of the 16S rRNA gene sequences indicated that SY095T was closely related to Crassaminicella profunda Ra1766HT (95.8 % 16S rRNA gene sequence identity). SY095T exhibited 78.1 % average nucleotide identity (ANI) to C. profunda Ra1766HT. The in silico DNA–DNA hybridization (DDH) value indicated that SY095T shared 22.7 % DNA relatedness with C. profunda Ra1766HT. On the basis of its phenotypic, genotypic and phylogenetic characteristics, SY095T is suggested to represent a novel species of the genus Crassaminicella , for which the name Crassaminicella thermophila sp. nov. is proposed. The type strain is SY095T (=JCM 34213=MCCC 1K04191). An emended description of the genus Crassaminicella is also proposed.

A hyperthermophilic, strictly anaerobic archaeon, designated strain SY113T, was isolated from a deep-sea hydrothermal vent chimney on the Southwest Indian Ridge at a water depth of 2770 m. Enrichment and isolation of strain SY113T were performed at 85 °C at 0.1 MPa. Cells of strain SY113T were irregular motile cocci with peritrichous flagella and generally 0.8–2.4 µm in diameter. Growth was observed at temperatures between 50 and 90 °C (optimum at 85 °C) and under hydrostatic pressures of 0.1–60 MPa (optimum, 27 MPa). Cells of SY113T grew at pH 4.0–9.0 (optimum, pH 5.5) and a NaCl concentration of 0.5–5.5 % (w/v; optimum concentration, 3.0 % NaCl). Strain SY113T was an anaerobic chemoorganoheterotroph and grew on complex proteinaceous substrates such as yeast extract and tryptone, as well as on maltose and starch. Elemental sulphur stimulated growth, but not obligatory for its growth. The G+C content of the genomic DNA was 55.0 mol%. Phylogenetic analysis of the 16S rRNA sequence of strain SY113T showed that the novel isolate belonged to the genus Thermococcus . On the basis of physiological characteristics, average nucleotide identity values and in silico DNA–DNA hybridization results, we propose a novel species, named Thermococcus aciditolerans sp. nov. The type strain is SY113T (=MCCC 1K04190T=JCM 39083T).

Antibiotic compounds in natural waters are normally present at low concentrations. In this paper, an easy and highly sensitive screening method using graphene oxide–functionalized magnetic composites (GO@NH2@Fe3O4) combined with matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) was established for twelve quinolone antibiotics. GO@NH2@Fe3O4 composites were utilized as adsorbents for magnetic solid-phase extraction. This method combines the advantages of magnetic solid-phase extraction and MALDI-TOF MS, which allows for fast detection of quinolones at low concentrations. To improve absorption efficiency, the following parameters were individually optimized: sample acidity, extraction time, amount of adsorbent used, eluent used, and desorption time. Under the optimum conditions, the established method gave a low detection limit of 0.010 mg/L and allowed the high-throughput screening of twelve quinolone antibiotics (enoxacin, norfloxacin, ciprofloxacin, pefloxacin, fleroxacin, gatifloxacin, enrofloxacin, levofloxacin, sparfloxacin, danofloxacin, difloxacin, and lomefloxacin). The proposed method, having an easily prepared sorbent with a high affinity for quinolones and a convenient, high-throughput detection step, has been shown to have merit for the detection of antibiotics in water samples.

A novel HPLC-UV method was developed for the determination of four tetracyclines based on magnetic solid phase extraction in tandem with liquid–liquid extraction. The water-soluble amino functionalized magnetite nanoparticle (MNP-NH(2)) was used as an adsorbent for extraction/preconcentration of tetracycline, oxytetracycline, chlortetracycline, and doxycycline from bovine milk samples. Fourier transform infrared spectrometer, transmission electron microscope, X-ray diffraction, and elemental analyze techniques were used to characterize the material. Some key parameters which influence liquid–liquid extraction and magnetic dispersive solid-phase extraction procedure, including volume of extraction solvent, the amount of adsorbent, the pH, extraction and desorption time, the composition of the eluent, and elution frequency were investigated. The proposed method exhibited a linear range of 50.0–2500.0 μg L(−1) (r(2) = 0.9941) with and good reproducibility (RSD

6-Hydroxy-3-succinoyl-pyridine (HSP) 3-monooxygenase (HspB), a flavoprotein essential to the pyrrolidine pathway of nicotine degradation, catalyzes pyridine-ring β-hydroxylation, resulting in carbon-carbon cleavage and production of 2,5-dihydroxypyridine. Here, we generated His6-tagged HspB in Escherichia coli, characterized the properties of the recombinant enzyme, and investigated its mechanism of catalysis. In contrast to conclusions reported previously, the second product of the HspB reaction was shown to be succinate, with isotope labeling experiments providing direct evidence that the newly introduced oxygen atom of succinate is derived from H2O. Phylogenetic analysis reveals that HspB is the most closely related to two p-nitrophenol 4-monooxygenases, and the experimental results exhibit that p-nitrophenol is a substrate of HspB. The reduction of HspB (with maxima at 375 and 460 nm, and a shoulder at 485 nm) by NADH was followed by stopped-flow spectroscopy, and the rate constant for reduction was shown to be stimulated by HSP. Reduced HspB reacts with oxygen to form a C(4a)-(hydro)peroxyflavin intermediate with an absorbance maximum at ∼400 nm within the first few milliseconds before converting to the oxidized flavoenzyme species. The formed C(4a)-hydroperoxyflavin intermediate reacts with HSP to form an intermediate that hydrolyzes to the products 2,5-dihydroxypyridine and succinate. The investigation on the catalytic mechanism of a flavoprotein pyridine-ring β-position hydroxylase provides useful information for the biosynthesis of pyridine derivatives.

The polymerization of N-(n-hexyl)-N‘-phenylcarbodiimide was studied using a number of homochiral catalysts based on binaphthol derivatives. All polymers showed optical activity due to the formation of a predominant screw sense controlled by the chirality of the catalyst. The helicity and chirality of these materials were studied by VCD, ECD, and polarimetry. Structures calculated using density functional theory were used to compare with their simulated VCD and experimental VCD, thus allowing the absolute screw sense to be determined. AFM imaging showed epitaxial ordering of these rigid chains on graphite surfaces and single chains measuring nearly 3 mm were observed in spin-cast samples on silicon.

The mono-azo dyes Disperse Red 1 and Disperse Red 19 have been studied for several years as chromophores in polymers for nonlinear optical properties. These materials are examined here for the effects of dye donor group esterification in guest−host systems and by dye−polymer covalent attachment on near-infrared absorption behavior. The dye−polymer systems DR1−acrylate, DR1−poly-4-vinylphenol, and DR19−aliphatic epoxy are characterized by UV−vis absorption spectroscopy and photothermal deflection spectroscopy as guest−host systems with and without esterification of the DR1 and DR19 ethanol −OH substituents in guest−host systems, and as covalently attached dye copolymers, as a function of dye concentration up to 1700 μmol per gram of polymer. Esterification is shown to be an effective route to reducing near-IR loss in DR1/acrylate guest−host materials at high concentrations and in DR19/epoxy guest−host materials at most concentrations. Dye−polymer covalent attachment is shown to be highly effective for mini...

The molecular weight and temperature dependencies of the intrinsic viscosity [η] were investigated for poly{2,7-[9,9-bis((S)-3,7-dimethyloctyl)]fluorene} (PDMOF) in tetrahydrofuran (THF). By analyzing the [η] data in terms of the touched-bead wormlike chain model, we estimated the persistence length q of PDMOF. It is 9.5 nm at 20 °C and slightly increases with decreasing temperature. The results of q were compared with the theoretical ones calculated on the basis of the broken wormlike chain (BWC), rotational isomeric state (RIS), and freely rotating chain (FRC) models. The BWC model for helical polymer chains gave q much larger than the experimental values, when the excess free energy ΔGr of the helix reversal for PDMOF was assumed to be comparable to those for typical synthetic helical polymers reported so far. On the other hand, the FRC model slightly underestimated the experimental q. A good fit to the experimental q was obtained for a simple RIS model where each monomer unit takes independently four ...

We report the first solution state circular dichroism (CD) spectroscopic properties of a newly designed polyfluorene (PF) featuring highly enantiopure β-branched chiral alkyl side chains, poly[2,7-{9,9-bis[(S)-2-methyloctyl]}fluorene] (PFMO), in dilute THF solution. Upon cooling the solution temperature, the single positive-sign CD band at 380 nm at +50 °C gradually changed into an apparent bisignate CD signal with two extrema of 403 and 355 nm at −80 °C, while the broad UV−vis band centered at 380 nm changed into a major intense band at 399 nm with a shoulder around 380 nm. On the basis of these data combined with photoluminescence (PL) studies and viscometric measurement, we concluded that PFMO in THF solution underwent a certain thermodriven, order−disorder conformational transition around 0 °C. It was considered that, upon cooling, the randomly twisted local PF backbone motifs in the wormlike PF backbone at higher temperature were transformed into a highly ordered PF backbone motif, possibly a P-52 he...

A new rod-like helical polysilane, poly{(S)-3,7-dimethyloctyl-(2-cyclopentylethyl)silane}, was found to undergo a thermo-driven, helix-helix transition at –33 ° C in isooctane associated with the discontinuous changes in the Siσ -Siσ *transition energy and intensity in the transition temperature region. This is the first example of a helix-helix transition polysilane with a cycloalkyl group. A similar rod-like polysilane derivative, poly{(S)-3,7-dimethyloctyl-(1-cyclopentylmethyl)silane}, however, did not undergo any helix-helix transition between –61 and 80 ° C.

The sustained effect of acupuncture refers to the lasting effect after the cease of acupuncture. Through large amount of acupuncture clinical practices and experimental researches, the objective existence of the sustained effect of acupuncture is approved. However, the lasting period of acupuncture effect may be related with category and stage of disease, individualized acupuncture reaction, acupuncture methods, intervals between treatments and therapeutic course. Therefore, it has great scientific significance and practice value to carry out further systematic and in-depth research on effect onset time of different diseases as well as the discipline of the sustained effect, so as to promote and prolong acupuncture effect.

The circular dichroism (CD) of a polythiophene in the molecularly dispersed state was observed for the first time. The polythiophene possesses two chiral alkyl side chains (poly{3,4-bis[(S)-2-methyloctyl]thiophene}, PDMOT). The chiroptical properties of this polymer in solution, aggregate, and thin solid film states were investigated. A chirally distorted main-chain conformation in a single molecule of PDMOT accounts for the observed CD spectra in solution and could also be considered as a novel chiral motif in an optically active polymer, besides the highly ordered, intramolecular helical structure and the chiral superstructure resulting from intermolecular π−π stacking. Significant temperature and solvent effects on the CD were also observed in the spectra.

To identify acupuncture resources in six databases of Cochrane Library (CL) with computer retrieve. Seventy-two literatures were identified in Cochrane Database of Systematic Reviews (CDSR). Among them, 12 Cochrane systematic review (CSR) verified the effectiveness of acupuncture, 29 concerning the indeterminacy of the efficacy of acupuncture with 1 didn't support acupuncture for epilepsy and 31 remained as protocols; 121 literatures were found in Database of Abstracts of Reviews of Effects (DARE) with more types of diseases or symptoms and rich modality comparing to CSR; 4218 randomized controlled trials and clinical controlled trials were identified in Cochrane Central Register of Controlled Trials (CCRCT); 43 literatures in Cochrane Methodology Register Database (CMRD) which focused on blindness study, quality assessment of methodology of research and publication bias and so on; 25 literatures in Health Technology Assessment Database (HTAD) and 18 in NHS Economic Evaluation Database (NHS EED) which were centered on acupuncture analgesia. Consequently, acupuncture literatures in 6 databases of CL do provide good resources for acupuncture researchers due to its abundant content, concrete classification and high quality evidence.

A series of chiral binaphthyl titanium alkoxide complexes were synthesized. Among them, chiral titanium complex [(R)-3,3'-dibromo-2,2'-binaphthoxy](di-tert-butoxy)titanium(IV) (R-3) exists as a crystallographic C2 dimer in the solid state but a monomer in solution at room temperature. Application of R-3 in the helix-sense-selective polymerization of achiral carbodiimide, N-(1-anthryl)-N'-octadecylcarbodiimide (1), yielded a well-defined regioregular, stereoregular poly[N-(1-anthryl)-N'-octadecylguanidine] (poly-1b) with a relatively narrow polymer dispersity index of 2.7. Full racemization of poly-1b at +80 degrees C in toluene requires more than 100 h. Interestingly, poly-1b was found to undergo fast reversible chiroptical switching at +38.5 degrees C in toluene. Furthermore, at room temperature, poly-1b shows a positively signed Cotton effect in toluene, but negative ones in THF and chloroform, respectively. The chiroptical switching takes place around the toluene content of 90% (vol) in the mixed toluene/THF solvents. This is the first example of chiroptical switching phenomenon occurring in a helical polymer possessing no chiral moieties in the polymer chains. We believe this reversible chiroptical switching phenomenon occurs by reorientation of anthracene rings relative to the chain director.

Using chiral catalysts of (R)- and/or (S)-BINOL-Ti, the asymmetrical polymerization of achiral monomer, N-(1-anthryl)-N'-n-octadecylcarbodiimide, yielded soluble nonregioregular polyguanidines of Poly-R1 and Poly-S1. A racemization process occurred when the toluene solution of Poly-R1 was annealed at elevated temperatures (70-80 degrees C). Kinetic studies reveal this to be a slow process with an activation energy of ca. 36 kcal/mol. On the other hand, using titanium(IV) trifluoroethoxide catalyst, the polymerization of N-(1-anthryl)-N'-[(R)- and/or (S)-3,7-dimethyloctyl]carbodiimides afforded highly regioregular polyguanidines of Poly-R2 and Poly-S2. These polymers adopt stable helices in various solvents and elevated temperatures, whose kinetically controlled conformations and thermodynamically controlled conformations are essentially the same.

Recent progress in developing high-performance nonlinear optical chromophores and polymers for electro-optics isreviewed. Using the single-mode focused microwave irradiation, a diversified family of 2,5-dihydrofuran derivativeshas been synthesized as a new class of tunable electron acceptors. Very large r 33 values (128 and 116 pm/V at 1.3 m)have been demonstrated by doping one of the 2-dicyanomethylen-3-cyano-4,5,-dimethyl-5-trifluoromethyl-2,5-dihydrofuran (CF 3 -TCF)-based chromophores in poly(methyl methacrylate) (PMMA) and a high T g polyquinoline (PQ-100), respectively. An excellent long-term temporal stability at 85 °C has also been maintained in the PQ system. Twoside-chain dendronized NLO polymers have been synthesized. Using a mild, simple, and generally applicable post-functionalization method, highly polarizable chromophores with dendritic modification has been covalently attached toside chains of poly(4-hydroxystyrene). This approach provides the combined advantages of achieving better polingefficiency through the dendritic effect and shortening the development time required for E-O dendrimer synthesis.Systematic property comparison between these polymers and other conventional NLO polymers, such as guest-host andsimple side-chain polymers, has been performed. Exceptionally high poling efficiency (a very large E-O coefficient of97 pm/V at 1.3 m) and good temporal stability at room temperature were demonstrated in this dendronized side-chainpolymer system.

Achieving asymmetric-aligned and thermo-stable bulky lattice of dipolar chromophores is one of most challenging tasks of molecular assembling. The work to be presented demonstrates, through nanoscale tailoring and smartly controlled lattice hardening, the full potential and performance integration of organic electro-optic polymers has been realized to an unprecedented level.

A new rod-like polysilylene bearing a β-branched alkyl group, poly[(S)-3,7-dimethyloctyl(2-ethylbutyl)silylene], was found to undergo a thermo-driven, helix–helix transition at −7 °C in isooctane associated with the discontinuous changes in the singlet σ–σ* excitation energy in the silicon backbone in the switching temperature region.

The first unsymmetrically substituted polyfluorene bearing a bulky poly(benzyl ether) dendron and less bulky 3,6-dioxaoctyl groups in the 9-position was designed and synthesized, which gives almost a pure bluish photoluminescence with negligible weak greenish excimer emission around 520 nm even in a thermally annealed thin solid film.