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1.
Biologicals ; 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32165080

RESUMO

Immunoglobulin preparations are one of the promising drugs for Alzheimer's disease (AD). Anti-ß-amyloid (Aß) oligomers antibodies in immunoglobulin preparations are considered to be critical for the therapeutic effect against Alzheimer's disease. However, the antibodies content in immunoglobulin preparations varies greatly. In order to determine which factor contributes to the difference of the antibodies content, the content of anti-Aß oligomers antibodies in multiple batches of immunoglobulin preparations from two manufacturers were measured by enzyme-linked immunosorbent assay. The results showed that no significant difference was found in the antibodies content among different bathes of normal immunoglobulin preparations prepared by the same process from the same manufacturer, whereas significant difference was found in the antibodies content between normal immunoglobulin preparations prepared by ethanol fractionation and those by chromatography process from the same manufacturer. In addition, significant variation existed in the antibodies content between normal immunoglobulin preparations and specific immunoglobulin preparations that are produced by plasma pool of immunized donors. Based on analysis of these results, the preparation process and raw plasma could be the main contributing factors affecting the content of anti-Aß oligomers antibodies in immunoglobulin preparations. This finding might help to develop AD-specific immunoglobulin preparation containing higher content of anti-Aß oligomers antibodies.

2.
Nat Commun ; 11(1): 83, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913275

RESUMO

Architecting grain crystallographic orientation can modulate charge distribution and chemomechanical properties for enhancing the performance of polycrystalline battery materials. However, probing the interplay between charge distribution, grain crystallographic orientation, and performance remains a daunting challenge. Herein, we elucidate the spatially resolved charge distribution in lithium layered oxides with different grain crystallographic arrangements and establish a model to quantify their charge distributions. While the holistic "surface-to-bulk" charge distribution prevails in polycrystalline particles, the crystallographic orientation-guided redox reaction governs the charge distribution in the local charged nanodomains. Compared to the randomly oriented grains, the radially aligned grains exhibit a lower cell polarization and higher capacity retention upon battery cycling. The radially aligned grains create less tortuous lithium ion pathways, thus improving the charge homogeneity as statistically quantified from over 20 million nanodomains in polycrystalline particles. This study provides an improved understanding of the charge distribution and chemomechanical properties of polycrystalline battery materials.

3.
J Org Chem ; 85(2): 622-632, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31799847

RESUMO

An efficient Pd-catalyzed arylation of alkylpyridine based on the pyridinium activation strategy has been developed for synthesis of mixed aryl alkylpyridines. It was found that (1) the N-methyl group in the pyridinium salts acted as a transient activator and could be automatically departed after the reaction, (2) CuBr was an indispensable additive for achieving the C6-selective arylation, (3) the α-branched alkyl chain on the alkylpyridine greatly increased the yield of the product. Deuterium labelling experiment revealed that in the case of the α-branched alkylpyridine, the presence of CuBr completely inhibited the H/D exchange at the benzylic position and thus enabled the selective arylation at the C6 position. This protocol demonstrates a broad substrate scope, and with respect to both the aryl iodides and the α-branched alkylpyridine, the desired mixed aryl alkylpyridines were obtained in generally good to excellent yields.

4.
Prep Biochem Biotechnol ; 50(1): 1-9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31441715

RESUMO

Isoquercitrin is a flavonoid with important applications in the pharmaceutical and nutraceutical industries. However, a low yield and high production cost hinders the industrial preparation of isoquercitrin. In the present study, isoquercitrin was prepared by biotransformation of rutin using α-L-rhamnosidase from Aspergillus niger JMU-TS528 combined with high-speed countercurrent chromatography (HSCCC) purification. As a result, the optimum transformation pH, temperature, and time were pH 4.0, 60 °C, and 60 min, respectively. The Km and Vmax were 0.36 mM and 0.460 mmol/min, respectively. For isoquercitrin production, the optimal rutin concentration and transformation time were approximately 1000 mg/L and 60 min. The rutin transformation rate reached 96.44%. The isoquercitrin was purified to a purity of 97.83% using one-step purification with HSCCC. The isoquercitrin was identified using UPLC-Q-TOF-MS. The comprehensive results indicated that the biotransformation procedure using the α-L-rhamnosidase from A. niger JMU-TS528 combined with HSCCC was a simple and effective process to prepare isoquercitrin, which might facilitate the production of isoquercitrin for industrial use.


Assuntos
Aspergillus niger/metabolismo , Glicosídeo Hidrolases/metabolismo , Quercetina/análogos & derivados , Rutina/metabolismo , Biotransformação , Distribuição Contracorrente , Microbiologia Industrial , Quercetina/isolamento & purificação , Quercetina/metabolismo
5.
J Behav Health Serv Res ; 47(1): 113-125, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30945109

RESUMO

The purpose of this study was a psychometric evaluation of the 4-item perceived social connectedness (PSC) scale. The study analyzed secondary data from a project that assessed physical, behavioral, and social health characteristics of adults with serious mental illness receiving integrated services at community mental health centers (CMHs). The current sample comprised those diagnosed with schizophrenia attending these CMHs (N = 146). Most participants were African-American males who receive disability benefits with Medicaid as health insurance. The sample self-reported low-to-moderate levels of social connectedness, daily functioning, and symptom severity. Factor analysis of the PSC scale revealed one dimension, accounting for 66% of total variance, with strong item loadings. Reliability coefficients indicated sufficient scale internal consistency. Construct validity was suggested via the PSC scale's directional, significant convergence with daily functioning and symptom severity. Implications include the application of the PSC scale for this socioeconomically disadvantaged population that customarily lacks meaningful social networks.

6.
Materials (Basel) ; 12(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540464

RESUMO

Engineering surface structure of catalysts is an efficient way towards high catalytic performance. Here, we report on the synthesis of regular iridium nanospheres (Ir NSs), with abundant atomic steps prepared by a laser ablation technique. Atomic steps, consisting of one-atom level covering the surface of such Ir NSs, were observed by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The prepared Ir NSs exhibited remarkably enhanced activity both for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in acidic medium. As a bifunctional catalyst for overall water splitting, they achieved a cell voltage of 1.535 V @ 10 mA/cm2, which is much lower than that of Pt/C-Ir/C couple (1.630 V @ 10 mA/cm2).

7.
Zookeys ; 865: 67-85, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379444

RESUMO

Five species of the genus Herpetogramma in China are studied with morphological and DNA barcode data. Herpetogrammabiconvexa Wan, Lu & Du, sp. nov., H.longispina Wan, Lu & Du, sp. nov., and H.brachyacantha Wan, Lu & Du, sp. nov. are described as new. Herpetogrammarudis (Warren) and H.magna (Butler) are newly diagnosed. Photographs of the habitus and genitalia of these five species are provided.

9.
Mycologia ; 111(5): 857-870, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31414967

RESUMO

In this paper, species of the genus Morchella are investigated in China. Based on morphological characteristics and molecular phylogenetic analyses of the nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and the combined data set ITS + nuclear large subunit rDNA (28S) + the translation elongation factor 1-α (TEF1) gene + RNA polymerase II first largest subunit (RPB1) + RNA polymerase II second largest subunit (RPB2), six new phylogenetic species are illustrated and described: M. clivicola, M. confusa, M. odonnellii, M. owneri, M. yangii, and M. yishuica. Furthermore, two new record species, M. dunensis and M. palazonii, which were only known in Europe, are now reported for the first time from Asia. New species of morels will provide additional information on species diversity and genetic resource candidates for improving the cultivation of this economically important fungus.

10.
ChemistryOpen ; 8(8): 1076-1083, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31406654

RESUMO

P450 119 peroxygenase was found to catalyze the sulfoxidation of thioanisole and the sulfonation of sulfoxide in the presence of tert-butyl hydroperoxide (TBHP) for the first time with turnover rates of 1549 min-1 and 196 min-1 respectively. Several mutants were designed to improve the peroxygenation activity and thioanisole specificity by site-directed mutagenesis. The F153G/T213G mutant gave an increase of sulfoxide yield and a decrease of sulfone yield. Moreover the S148P/I161T/K199E/T214V mutant and the K199E mutant with acidic Glu residue contributed to improving the product ratio of sulfoxide to sulfone. Addition of short-alkyl-chain organic acids to the P450 119 peroxygenase-catalyzed sulfur oxidation of thioanisole was investigated. Octanoic acid was found to induce a preferred sulfoxidation of thioanisole catalyzed by the F153G/T213G mutant to give approximately 2.4-fold increase in turnover rate with a k cat value of 3687 min-1 relative to that of the wild-type, and by the F153G mutant to give the R-sulfoxide up to 30 % ee. The experimental control and the proposed mechanism for the P450 119 peroxygenase-catalyzed sulfoxidation of thioanisole in the presence of octanoic acid suggested that octanoic acid could partially occupy the substrate pocket; meanwhile the F153G mutation could enhance the substrate specificity, which could lead to efficiently regulate the spatial orientation of thioanisole and facilitate the formation of Compound I. This is the most effective catalytic system for the P450 119 peroxygenase-catalyzed sulfoxidation of thioanisole.

11.
Small ; 15(42): e1902582, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31448555

RESUMO

The electroreduction of carbon dioxide (CO2 ) toward high-value fuels can reduce the carbon footprint and store intermittent renewable energy. The iodide-ion-assisted synthesis of porous copper (P-Cu) microspheres with a moderate coordination number of 7.7, which is beneficial for the selective electroreduction of CO2 into multicarbon (C2+ ) chemicals is reported. P-Cu delivers a C2+ Faradaic efficiency of 78 ± 1% at a potential of -1.1 V versus a reversible hydrogen electrode, which is 32% higher than that of the compact Cu counterpart and approaches the record (79%) reported in the same cell configuration. In addition, P-Cu shows good stability without performance loss throughout a continuous operation of 10 h.

12.
Chem Commun (Camb) ; 55(59): 8579-8582, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31274136

RESUMO

FeCo2O4 nanoparticles with abundant oxygen vacancies were produced by laser fragmentation. The oxygen vacancies can lower the thermodynamic energy barriers as well as accelerate the electron transfer, eventually promoting oxygen evolution and reduction reactions simultaneously.

13.
J Neurosci ; 39(38): 7604-7614, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31270158

RESUMO

Dysregulated adult hippocampal neurogenesis occurs in many temporal lobe epilepsy (TLE) models. Most dentate granule cells (DGCs) generated in response to an epileptic insult develop features that promote increased excitability, including ectopic location, persistent hilar basal dendrites (HBDs), and mossy fiber sprouting. However, some appear to integrate normally and even exhibit reduced excitability compared to other DGCs. To examine the relationship between DGC birthdate, morphology, and network integration in a model of TLE, we retrovirally birthdated either early-born [EB; postnatal day (P)7] or adult-born (AB; P60) DGCs. Male rats underwent pilocarpine-induced status epilepticus (SE) or sham treatment at P56. Three to six months after SE or sham treatment, we used whole-cell patch-clamp and fluorescence microscopy to record spontaneous excitatory and inhibitory currents from birthdated DGCs. We found that both AB and EB populations of DGCs recorded from epileptic rats received increased excitatory input compared with age-matched controls. Interestingly, when AB populations were separated into normally integrated (normotopic) and aberrant (ectopic or HBD-containing) subpopulations, only the aberrant populations exhibited a relative increase in excitatory input (amplitude, frequency, and charge transfer). The ratio of excitatory-to-inhibitory input was most dramatically upregulated for ectopically localized DGCs. These data provide definitive physiological evidence that aberrant integration of post-SE, AB DGCs contributes to increased synaptic drive and support the idea that ectopic DGCs serve as putative hub cells to promote seizures.SIGNIFICANCE STATEMENT Adult dentate granule cell (DGC) neurogenesis is altered in rodent models of temporal lobe epilepsy (TLE). Some of the new neurons show abnormal morphology and integration, but whether adult-generated DGCs contribute to the development of epilepsy is controversial. We examined the synaptic inputs of age-defined populations of DGCs using electrophysiological recordings and fluorescent retroviral reporter birthdating. DGCs generated neonatally were compared with those generated in adulthood, and adult-born (AB) neurons with normal versus aberrant morphology or integration were examined. We found that AB, ectopically located DGCs exhibit the most pro-excitatory physiological changes, implicating this population in seizure generation or progression.

14.
Int J Biol Macromol ; 137: 177-186, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31255619

RESUMO

Gracilaria is a genus of red algae widely cultivated in Asia and is notable for its economic importance as food ingredients. Neoagaro oligosaccharides (NAOSs) are products of Gracilaria that have excellent water solubility, antioxidant activity and prebiotic effect. In this study, Gracilaria crude polysaccharide was treated with agarase and hydrolyzed into NAOSs with different degrees of polymerization (DP). The compositions of the hydrolyzed NAOSs were analyzed by electrospray ionization-time of flight-mass spectrometry and thin layer chromatography. The antioxidant capacity and prebiotic effects of NAOSs with different DPs were investigated and the results showed that DP could affect the antioxidant capacity of NAOSs. The prebiotic effects of NAOSs with different DP were evaluated based on the influence on the growth of four intestinal bacteria. NAOSs promoted the growth of Lactobacillus delbrueckii subsp. bulgaricus and Sterptococcus thermophilus. The protective effect of Gracilaria NAOSs in simulated gastrointestinal juice was also studied. Finally, NAOSs with best prebiotic effects were used in Procambarus feeding experiment and exhibited promotion effect on Procambarus growth. The present study showed that Gracilaria NAOSs can be utilized as antioxidant and prebiotic additive, which had a considerable potential in food and feed industry.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Glicosídeo Hidrolases/metabolismo , Gracilaria/química , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Prebióticos , Animais , Antioxidantes/metabolismo , Astacoidea/efeitos dos fármacos , Astacoidea/crescimento & desenvolvimento , Biomimética , Indústria Alimentícia , Trato Gastrointestinal/metabolismo , Hidrólise , Oligossacarídeos/metabolismo
15.
Fungal Biol ; 123(7): 528-538, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31196522

RESUMO

Recently, Morchella importuna, M. sextelata, M. eximia, M. exuberans, Mel-13, and Mel-21 have been successfully cultivated in China and planting areas rapidly expanded because of their economic importance. Effective molecular markers are urgently needed for accurately identifying morel cultivars. Microsatellites are widely utilized for strain authentication in many fungal groups. To our knowledge, for the first time we characterized the distribution of microsatellites (simple sequence repeats, SSRs) in the M. importuna genome with 12902 SSRs and reported the first set of SSRs developed for Morchella species. Mono-nucleotides (66.2 %) were the most frequent motifs, followed by tri- (15.4 %), di- (12.1 %), tetra- (3.7 %), penta- (1.3 %) and hexa-nucleotides (1.3 %). We tested the cross-species amplification of 180 SSRs on 24 samples from the six species and high cross-species transferability of SSRs (87.7 %) was found. Among twenty-two microsatellites selected for genetic diversity analysis on 127 samples from the six species, fifteen to twenty polymorphic loci were identified in M. importuna, M. sextelata, M. eximia, M. exuberans, Mel-13 and Mel-21. Interspecific hybridization events were detected among morel species, indicating the potential application of morel crossbreeding. Ninety-one cultivated samples were characterized as new cultivars with different genotypes, but cultivar names used for these by farmers was confusing, with misnaming, synonyms and homonyms. Our results are not only helpful for cultivar identification and morel breeding programs in China, but also provide molecular tools for genetic studies in morels.


Assuntos
Ascomicetos/genética , Repetições de Microssatélites/genética , Ascomicetos/classificação , China , Análise por Conglomerados , DNA Fúngico/genética , Marcadores Genéticos , Genoma Fúngico/genética , Genótipo , Hibridização Genética , Polimorfismo Genético
16.
Clin Ther ; 41(6): 1097-1109, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31053296

RESUMO

PURPOSE: The combination of warfarin and compound Danshen dripping pill (CDDP) is helpful for patients with both coronary heart disease (CHD) and atrial fibrillation (AF). The main adverse drug reaction of warfarin is bleeding because of its narrow therapeutic index. The safety of a combination therapy with warfarin and CDDP is always a concern. Our previous research showed that the combination of warfarin and CDDP improved the quality of life for patients with both CHD and AF. This study describes the changes in dose and concentration of warfarin necessary and evaluates bleeding risk when warfarin is given concomitantly with CDDP. METHODS: An ultra-performance liquid chromatography-MS/MS method with a chiral column was developed to assay the concentration of S-warfarin and R-warfarin in human plasma simultaneously. The method was applied to compare the concentration of warfarin in patients taking warfarin combined with CDDP and without CDDP. International normalized ratio (INR) values were monitored to evaluate bleeding risk. Paired t tests were then used to compare the dose and the concentration in 2 periods. Moreover, patients with VKORC1, CYP2C9*3, CYP4F2, EPHX1, and PROC gene polymorphisms were evaluated to determine interactions. FINDINGS: The results indicate that the dose of warfarin had no significant change with or without CDDP. Also, the peak concentrations of S-warfarin and total warfarin were significantly different in CYP4F2 C/C patients, but there was no significant difference identified in other genetic groups. No bleeding occurred in the study. IMPLICATIONS: The dose of warfarin would be sustainable when combined with CDDP, because CDDP did not affect concentration of warfarin significantly in most patients and the change of INR was not significant. CHINA CLINICAL TRIAL REGISTRY IDENTIFIER: ChiCTR-ONRC-13003523.

17.
Clin Proteomics ; 16: 22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139026

RESUMO

Background: Chinese Bama Yao Autonomous County is a well-known longevity region in the world. In the past 30 years, population and genome studies were undertaken to investigate the secret of longevity and showed that longevity is the result of a combination of multiple factors, such as genetic, environmental and other causes. In this study, characteristics of the blood plasma proteomic and autoantibody profiles of people from Bama longevity family were investigated. Methods: Sixty-six plasma donors from Chinese Bama longevity area were recruited in this study. Thirty-three offsprings of longevous families were selected as case studies (Longevous group) and 33 ABO (blood type), age, and gender-matched subjects from non-longevous families were selected as controls (Normal group). Each group contains 3 biological replicates. Tandem mass tag-based proteomic technique was used to investigate the differentially expressed plasma proteins between the two groups. The auto-reactive IgG antibody profiles of the 3 pooled samples in each group were revealed by human proteome microarrays with 17,000 recombinant human proteins. Results: Firstly, 525 plasma proteins were quantified and 12 proteins were discovered differentially expressed between the two groups. Secondly, more than 500 proteins were recognized by plasma antibodies, 14 proteins ware differentially reacted with the autoantibodies in the two groups. Bioinformatics analysis showed some of the differential proteins and targeted autoantigens were involved in cancer, cardiovascular disease and immunity. Conclusions: Proteomic and autoantibody profiles varied between the offspring of longevous and normal families which are from the same area and shared the same environmental factors. The identified differences were reported to be involved in several physiological and pathological pathways. The identified proteins will contribute to a better understanding of the proteomic characteristics of people from Bama longevous area and a revelation of the molecular mechanisms of longevity.

18.
R Soc Open Sci ; 6(2): 181035, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30891258

RESUMO

This study presents a novel construction pre-supporting system for large underground space excavation with shallow depth, Steel Tube Slab system (STS), in which adjacent steel pipes are connected by a couple of flanges, bolts and concrete for flexural capacity and lateral stiffness of the whole structure. The STS method is employed for the first time for the construction of the ultra-shallow buried and large span subway station in China, during which ground settlement and structural deformation are monitored. A numerical model for the subway station is established with reliability verified by monitored data comparison from numerical results and investigation on the effect of large span underground excavation on surrounding soil surrounding soil and existing buildings in soft soils. Unlike traditional methods, the STS method can effectively control and reduce the ground settlement during construction, thereby rendering it ideally suited for application in soft soils.

19.
Artigo em Inglês | MEDLINE | ID: mdl-30877981

RESUMO

This paper developed a novel, sensitive, and selective ultra-performance liquid chromatography-triple quad mass spectrometry method to simultaneously determine seven effective constituents (triptolide, triptophenolide, celastrol, wilforgine, wilforine, wilfordine and wilfortrine) of Tripterygium glycosides (GTW) in human serum and urine. The chromatographic separation was performed on the C18 column using an ammonium acetate buffer solution-acetonitrile (both containing 0.1% formic acid) in a gradient program with a flow rate of 0.3 mL/min. Monitoring reaction mode was applied to target compounds quantitative analysis in the positive electrospray ionization (ESI) mode. The analysis process took 11 min in total. This method was fully validated with a linear range of 1-200 ng/mL for triptolide, 0.4-80 ng/mL for celastrol, 0.1-20 ng/mL for triptophenolide, wilforgine, wilforine, wilfordine, and wilfortrine. The intra-day and inter-day accuracy and precision of the target compounds all met the 15% criterion in both serum and urine. Extraction recovery, matrix effect, and dilution integrity were also validated. The short-term and long-term stability results indicated that all the constituents were stable in human serum and urine under the investigated storage conditions. 10 patients' specimens were collected and analyzed. Most of the compounds exhibited the tendency of higher concentration in urine than that in serum. The concentration that was detected in the serum and in the urine of alkaloids showed a positive-correlation property. This is the first time that triptophenolide was quantified in human bio-matrices. The method is feasible for multi-components therapeutic monitoring or pharmacokinetics study in clinical pharmaceutical research of Tripterygium glycosides.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos/sangue , Lactonas/sangue , Terpenos/sangue , Tripterygium/química , Estabilidade de Medicamentos , Medicamentos de Ervas Chinesas , Glicosídeos/química , Glicosídeos/urina , Humanos , Lactonas/química , Lactonas/urina , Limite de Detecção , Modelos Lineares , Extratos Vegetais/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Terpenos/química , Terpenos/urina
20.
Adv Mater ; 31(16): e1807771, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30828895

RESUMO

The practical scale-up of renewable energy technologies will require catalysts that are more efficient and durable than present ones. This is, however, a formidable challenge that will demand a new capability to tailor the electronic structure. Here, an original electronic structure tailoring of CoO by Ni and Zn dual doping is reported. This changes it from an inert material into one that is highly active for the hydrogen evolution reaction (HER). Based on combined density functional theory calculations and cutting-edge characterizations, it is shown that dual Ni and Zn doping is responsible for a highly significant increase in HER activity of the host oxide. That is, the Ni dopants cluster around surface oxygen vacancy of the host oxide and provide an ideal electronic surface structure for hydrogen intermediate binding, while the Zn dopants distribute inside the host oxide and modulate the bulk electronic structure to boost electrical conduction. As a result, the dual-doped Ni, Zn CoO nanorods achieve current densities of 10 and 20 mA cm-2 at overpotentials of, respectively, 53 and 79 mV. This outperforms reported state-of-the-art metal oxide, metal oxide/metal, metal sulfide, and metal phosphide catalysts.

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