Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 33
Filter
1.
Chem Soc Rev ; 53(7): 3384-3456, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38411207

ABSTRACT

The scientific community has witnessed extensive developments and applications of organoboron compounds as synthetic elements and metal-free catalysts for the construction of small molecules, macromolecules, and functional materials over the last two decades. This review highlights the achievements of organoboron-mediated polymerizations in the past several decades alongside the mechanisms underlying these transformations from the standpoint of the polymerization mode. Emphasis is placed on free radical polymerization, Lewis pair polymerization, ionic (cationic and anionic) polymerization, and polyhomologation. Herein, alkylborane/O2 initiating systems mediate the radical polymerization under ambient conditions in a controlled/living manner by careful optimization of the alkylborane structure or additives; when combined with Lewis bases, the selected organoboron compounds can mediate the Lewis pair polymerization of polar monomers; the bicomponent organoboron-based Lewis pairs and bifunctional organoboron-onium catalysts catalyze ring opening (co)polymerization of cyclic monomers (with heteroallenes, such as epoxides, CO2, CO, COS, CS2, episulfides, anhydrides, and isocyanates) with well-defined structures and high reactivities; and organoboranes initiate the polyhomologation of sulfur ylides and arsonium ylides providing functional polyethylene with different topologies. The topological structures of the produced polymers via these organoboron-mediated polymerizations are also presented in this review mainly including linear polymers, block copolymers, cyclic polymers, and graft polymers. We hope the summary and understanding of how organoboron compounds mediate polymerizations can inspire chemists to apply these principles in the design of more advanced organoboron compounds, which may be beneficial for the polymer chemistry community and organometallics/organocatalysis community.

2.
CNS Neurosci Ther ; 29(12): 3935-3942, 2023 12.
Article in English | MEDLINE | ID: mdl-37334755

ABSTRACT

AIMS: The prediction of outcomes in convulsive status epilepticus (CSE) remains a constant challenge. The Encephalitis-Nonconvulsive Status Epilepticus-Diazepam Resistance-Image Abnormalities-Tracheal Intubation (END-IT) score was a useful tool for predicting the functional outcomes of CSE patients, excluding cerebral hypoxia patients. With further understanding of CSE, and in view of the deficiencies of END-IT itself, we consider it necessary to modify the prediction tool. METHODS: The prediction model was designed from a cohort of CSE patients from Xijing Hospital (China), between 2008 and 2020. The enrolled subjects were randomly divided into training cohort and validation cohort as a ratio of 2:1. The logistic regression analysis was performed to identify the predictors and construct the nomogram. The performance of the nomogram was assessed by calculating the concordance index, and creating calibration plots to check the consistency between the predicted probabilities of poor prognosis and the actual outcomes of CSE. RESULTS: The training cohort included 131 patients and validation cohort included 66 patients. Variables included in the nomogram were age, etiology of CSE, non-convulsive SE, mechanical ventilation, abnormal albumin level at CSE onset. The concordance index of the nomogram in the training and validation cohorts was 0.853 (95% CI, 0.787-0.920) and 0.806 (95% CI, 0.683-0.923), respectively. The calibration plots showed an adequate consistency between the reported and predicted unfavorable outcomes of patients with CSE at 3 months after discharge. CONCLUSIONS: A nomogram for predicting the individualized risks of poor functional outcomes in CSE was constructed and validated, which has been an important modification of END-IT score.


Subject(s)
Encephalitis , Status Epilepticus , Humans , Nomograms , Prognosis , Status Epilepticus/diagnosis , Status Epilepticus/therapy , Status Epilepticus/etiology , Encephalitis/complications , Diazepam
3.
J Am Chem Soc ; 144(43): 19896-19909, 2022 11 02.
Article in English | MEDLINE | ID: mdl-36256447

ABSTRACT

Switchable catalysis, in combination with epoxide-involved ring-opening (co)polymerization, is a powerful technique that can be used to synthesize various oxygen-rich block copolymers. Despite intense research in this field, the sequence-controlled polymerization from epoxide congeners has never been realized due to their similar ring-strain which exerts a decisive influence on the reaction process. Recently, quaternary ammonium (or phosphonium)-containing bifunctional organoboron catalysts have been developed by our group, showing high efficiency for various epoxide conversions. Herein, we, for the first time, report an operationally simple pathway to access well-defined polyether-block-polycarbonate copolymers from mixtures of epoxides by switchable catalysis, which was enabled through thermodynamically and kinetically preferential ring-opening of terminal epoxides or internal epoxides under different atmospheres (CO2 or N2) using one representative bifunctional organoboron catalyst. This strategy shows a broad substrate scope as it is suitable for various combinations of terminal epoxides and internal epoxides, delivering corresponding well-defined block copolymers. NMR, MALDI-TOF, and gel permeation chromatography analyses confirmed the successful construction of polyether-block-polycarbonate copolymers. Kinetic studies and density functional theory calculations elucidate the reversible selectivity between different epoxides in the presence/absence of CO2. Moreover, by replacing comonomer CO2 with cyclic anhydride, the well-defined polyether-block-polyester copolymers can also be synthesized. This work provides a rare example of sequence-controlled polymerization from epoxide mixtures, broadening the arsenal of switchable catalysis that can produce oxygen-rich polymers in a controlled manner.


Subject(s)
Carbon Dioxide , Epoxy Compounds , Epoxy Compounds/chemistry , Kinetics , Carbon Dioxide/chemistry , Oxygen , Catalysis , Polymers/chemistry , Carbonates
4.
Angew Chem Int Ed Engl ; 61(46): e202210243, 2022 Nov 14.
Article in English | MEDLINE | ID: mdl-36131491

ABSTRACT

Poly(cyclopentene carbonate) (PCPC) produced by copolymerization of CO2 and cyclopentene oxide (CPO) is a promising but challenging chemical recyclable polymer that has high potential in minimizing plastic pollution and maximizing CO2 utilization. Currently, problems remain to be solved, include low reactivity of toxic metal catalysts, inevitable byproducts, and especially the ambiguous mechanism understanding. Herein, we present the first metal-free access to PCPC by using a series of modular dinuclear organoboron catalysts. PCPC was afforded in an unprecedented catalytic efficiency of 1.0 kg of PCPC/g of catalyst; while the depolymerization of PCPC abides by a combination pathway of random chain scission and chain unzipping, returning CPO in near-quantitative yield (>99 %). The preparation and depolymerization of PCPC along with in depth understanding of related mechanisms would be helpful for further development of advanced catalysts and recyclable plastics.

5.
Carbohydr Res ; 520: 108643, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35977445

ABSTRACT

The functionalization of glycosides with ionic compounds such as ionic liquids provides enhanced polarity for the labelled glycans thanks to the presence of a permanent positive charge. The chemical derivatisation of glycans with ionic liquids constitutes an emerging strategy to boost the detection sensitivity in MS applications. This allows the straightforward monitoring and detection of the presence of labelled glycans in complex matrices and in those cases where very limited amounts of material were available such as in biological samples and chemoenzymatic reactions. The use of ionic liquid based derivatisation agents can be further exploited for the labelling of live cells via metabolic oligosaccharide engineering for the detection of cancer biomarkers and for the tuning of live cells-surface properties with implications in cancer prognosis and progression. In this mini-review we summarise the latest development of the ionic liquid based derivatisation agents in glycoscience focussing on their use for sensitive MS applications.


Subject(s)
Ionic Liquids , Ionic Liquids/chemistry , Ions
6.
J Org Chem ; 87(5): 3145-3155, 2022 Mar 04.
Article in English | MEDLINE | ID: mdl-35073078

ABSTRACT

The bifunctional thiourea catalyst system with both electrophilic and nucleophilic centers has been certified to be effective for fixing CO2 under mild reaction conditions; however, many questions remain, especially concerning the relationship between structure and performance. Herein, we systematically studied a series of such bifunctional catalysts with different chain lengths, nucleophilic anions, and substituents, which impact obvious influence on the catalytic performance. The activation energies of catalysts with different chain lengths are calculated via in situ IR. On this basis, we disclosed for the first time that the spacer length of tetramethylene -(CH2)6- is the optimal spatial effect for the coupling of epoxides and CO2. Particularly, the single crystal X-ray diffraction analysis of the molecular structures of the bifunctional catalyst C8 indicated the discovery of the existence of interaction force between the sulfur atom on the thiourea group and one hydrogen atom on the benzene ring, as well as the intermolecular hydrogen bonding interaction of the bromide (Br-) and two NH groups on the thiourea group. The catalyst structure performance, direct observation of the crystal structure, the thermodynamic study, and a wide range of substrates (12 examples) should be informative on the optimization of the existing catalysts or the design of new catalysts in the future.

7.
Acc Chem Res ; 54(23): 4434-4448, 2021 Dec 07.
Article in English | MEDLINE | ID: mdl-34806374

ABSTRACT

ConspectusElectron-deficient boron-based catalysts with metal-free but metallomimetic characteristics provide a versatile platform for chemical transformations. However, their catalytic performance is usually lower than that of the corresponding metal-based catalysts. Furthermore, many elaborate organoboron compounds are produced via time-consuming multistep syntheses with low yields, presenting a formidable challenge for large-scale applications of these catalysts. Given this context, the development of organoboron catalysts with the combined advantages of high efficiency and easy preparation is of critical importance.Therefore, we envisioned that the construction of a dynamic Lewis multicore system (DLMCS) by integrating the Lewis acidic boron center(s) and a Lewis basic ammonium salt in one molecule would be particularly efficient for on-demand applications because of the intramolecular synergistic effect. This Account summarizes our recent efforts in developing modular organoboron catalysts with unprecedented activities for several chemical transformations. A series of mono-, di-, tri-, and tetranuclear organoboron catalysts was readily designed and prepared in nearly quantitative yields over two steps using commercially available feedstocks. Notably, these catalysts can be modularly tailored by fine control over the electrophilic property of the Lewis acidic boron center(s), electronic and steric effects of the electropositive ammonium cation, linker length between the boron center and the ammonium cation, the number of boron centers, and the nucleophilic anion. This modular design allows systematic manipulation of the reactivity and efficacy of the catalysts, thus optimizing suitable catalysts for versatile chemical transformations. These include the coupling of CO2 and epoxides, copolymerization of CO2 and epoxides, ring-opening polymerization (ROP) of epoxides, and ring-opening copolymerization (ROCOP) of epoxides and cyclic anhydrides.The utilization of mononuclear organoboron catalysts provided a turnover frequency of 11050 h-1 for the CO2/propylene oxide coupling reaction, an unprecedented efficiency of 5.0 kg of polymer/g of catalyst for the copolymerization of CO2 and cyclohexene oxide, and a record-breaking catalytic efficiency of 7.4 kg of polymer/g of catalyst for the ROCOP of epoxides with cyclic anhydrides. A turnover number of 56500 was observed at a catalyst loading of 10 ppm for the ROP of epoxides using the dinuclear catalysts. The tetranuclear organoboron catalysts realized the previously intractable task of the copolymerization of CO2 and epichlorohydrin, producing poly(chloropropylene carbonate) with the highest molecular weight of 36.5 kg/mol reported to date.Furthermore, the study revealed that the interaction between the dynamic Lewis multicore, that is, the intramolecular synergistic effect between the boron center(s) and the quaternary ammonium salt, plays a key role in mediating the catalytic activity and selectivity. This was based on investigations of the crystal structures of the catalysts, key intermediates, reaction kinetics, and density functional theory calculations. The modular tactics for the construction of organoboron catalysts presented in this Account should inspire more advanced catalyst designs.

8.
J Cancer ; 12(16): 4791-4809, 2021.
Article in English | MEDLINE | ID: mdl-34234850

ABSTRACT

Background: Hepatocellular carcinoma (HCC) presents a common malignant tumor worldwide. Although kinectin 1 (KTN1) is the most frequently identified antigen in HCC tissues, the detailed roles of KTN1 in HCC remain unknown. This study seeks to clarify the expression status and clinical value of KTN1 in HCC and to explore the complicated biological functions of KTN1 and its underlying mechanisms. Methods: In-house reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of KTN1 in HCC tissues. External gene microarrays and RNA-sequencing datasets were downloaded to confirm the expression patterns of KTN1. The prognostic ability of KTN1 in HCC was assessed by a Kaplan-Meier curve and a hazard ratio forest plot. The CRISPR/Cas9 gene-editing system was used to knock out KTN1 in Huh7 cells, which was verified by PCR-Sanger sequencing and western blotting. Assays of cell migration, invasion, viability, cell cycle, and apoptosis were conducted to explore the biological functions. RNA sequencing was performed to quantitatively analyze the functional deregulation in KTN1-knockout cells compared to Huh7-wild-type cells. Upregulated genes that co-expressed with KTN1 were identified from HCC tissues and were functionally annotated. Results: KTN1 expression was increased in HCC tissues (standardized mean difference [SMD] = 0.20 [0.04, 0.37]). High KTN1 expression was significantly correlated with poorer prognosis of HCC patients, and KTN1 may be an independent risk factor for HCC (pooled HRs = 1.31 [1.05, 1.64]). After KTN1-knockout, the viability, migration, and invasion ability of HCC cells were inhibited. The proportion of HCC cells in the G0-G1 phases increased after KTN1 knockout, which also elevated the apoptosis rates in HCC cells. Several cascades, including innate immune response, chemical carcinogenesis, and positive regulation of transcription by RNA polymerase II, were dramatically changed after KTN1 knockout. KTN1 primarily participated in the cell cycle, DNA replication, and microRNAs in cancer pathways in HCC tissues. Conclusion: Upregulation of KTN1 served as a promising prognosticator in HCC patients. KTN1 promotes the occurrence and deterioration of HCC by mediating cell survival, migration, invasion, cell cycle activation, and apoptotic inhibition. KTN1 may be a therapeutic target in HCC patients.

9.
Chem Commun (Camb) ; 57(57): 7003-7006, 2021 Jul 15.
Article in English | MEDLINE | ID: mdl-34159978

ABSTRACT

A novel imidazolium derivative (GITag) shows superior ionisation and consequently allows increased mass spectrometric detection capabilities of oligosaccharides and N-glycans. Here we demonstrate that human serum samples can be directly labelled by GITag on a MALDI target plate, abrogating prevalently required sample pretreatment or clean-up steps.


Subject(s)
Glycosides/blood , Imidazoles/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Acetylglucosamine/blood , Acetylglucosamine/chemistry , Amination , Humans , Lactose/blood , Lactose/chemistry , Limit of Detection
10.
Angew Chem Int Ed Engl ; 60(35): 19253-19261, 2021 Aug 23.
Article in English | MEDLINE | ID: mdl-34109722

ABSTRACT

Producing polyesters with high molecular weight (Mn ) through ring-opening copolymerization (ROCOP) of epoxides with cyclic anhydrides remains a major challenge. Herein, we communicate a metal-free, highly active, and high thermoresistance system for the ROCOP of epoxides with cyclic anhydrides to prepare polyesters (13 examples). The organoboron catalysts can endure a reaction temperature as high as 180 °C for the ROCOP of cyclohexane oxide (CHO) with phthalic anhydride (PA) without the observation of any side reactions. The average Mn of the produced poly(CHO-alt-PA) climbed to 94.5 kDa with low polydispersity (Ð=1.19). Furthermore, an unprecedented turnover number of 9900, equivalent to an efficiency of 7.4 kg of polyester/g of catalyst, was achieved at a feed ratio of CHO/PA/catalyst=20000:10000:1 at 150 °C. Kinetic studies, crystal structure analysis, 11 B NMR spectra, and DFT calculations provided mechanistic justification for the effectiveness of the catalyst system.

11.
Sheng Li Xue Bao ; 73(2): 223-232, 2021 Apr 25.
Article in English | MEDLINE | ID: mdl-33903884

ABSTRACT

The present study was aimed to investigate the role of GluN2B-BDNF pathway in the cerebrospinal fluid-contacting nucleus (CSF-CN) in neuropathic pain. Intra-lateral ventricle injection of cholera toxin subunit B conjugated with horseradish peroxidase (CBHRP) was used to label the CSF-CN. Double-labeled immunofluorescent staining and Western blot were used to observe the expression of GluN2B and BDNF in the CSF-CN. Chronic constriction injury of sciatic nerve (CCI) rat model was used to duplicate the neuropathic pain. Pain behavior was scored to determine the analgesic effects of GluN2B antagonist Ro 25-6981 and BDNF neutralizing antibody on CCI rats. GluN2B and BDNF were expressed in the CSF-CN and their expression was up-regulated in CCI rats. Intra-lateral ventricle injection of GluN2B antagonist Ro 25-6981 or BDNF neutralizing antibody notably alleviated thermal hyperalgesia and mechanical allodynia in CCI rats. Moreover, the increased expression of BDNF protein in CCI rats was reversed by intra-lateral ventricle injection of Ro 25-6981. These results suggest that GluN2B and BDNF are expressed in the CSF-CN and alteration of GluN2B-BDNF pathway in the CSF-CN is involved in the modulation of the peripheral neuropathic pain.


Subject(s)
Brain-Derived Neurotrophic Factor , Neuralgia , Animals , Hyperalgesia , Rats , Rats, Sprague-Dawley , Sciatic Nerve
12.
J Mater Chem B ; 9(8): 1980-1987, 2021 03 04.
Article in English | MEDLINE | ID: mdl-33595048

ABSTRACT

A hierarchical multichannel polydopamine (HMPDA) nanoparticle with ample chondroitin sulfate (CS) is fabricated via modification of the silane coupling agent (APTES), followed by grafting CS on the unique bicontinuous open channels of HMPDA through amidation reaction. The obtained nanoparticles with both mesopores and macropores, abbreviated as HMPDA-A-CS15, possess a total pore volume of 0.3398 cm3 g-1, and a large surface area up to 69.10 m2 g-1. The as-prepared HMPDA-A-CS15 exhibits significantly enhanced selectivity for the separation of LDL, which is attributed to the specific recognition effect of CS for LDL. Furthermore, the unique large open channels endow the HMPDA-A-CS15 nanoparticles with a gratifying sorption capacity (1015.2 mg g-1) for LDL adsorption. The captured LDL can be stripped using 0.5% (v/v) ammonia solution with the advantage of easy atomization in downstream mass spectrometry (MS) analyses, and a recovery of 71.7% is achieved. Moreover, HMPDA-A-CS15 is further employed in the enrichment of LDL, which can be separated from the complex serum of simulated hypercholesterolemia patients with a favorable adsorption performance, as illustrated by the SDS-PAGE technique.


Subject(s)
Chemical Fractionation/methods , Chondroitin Sulfates/chemistry , Indoles/chemistry , Lipoproteins, LDL/isolation & purification , Nanoparticles/chemistry , Polymers/chemistry , Adsorption , Lipoproteins, LDL/chemistry , Mass Spectrometry , Silanes/chemistry , Time Factors
13.
J Am Chem Soc ; 143(9): 3455-3465, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33591738

ABSTRACT

The copolymerization of carbon dioxide (CO2) and epoxides to produce aliphatic polycarbonates is a burgeoning technology for the large-scale utilization of CO2 and degradable polymeric materials. Even with the wealth of advancements achieved over the past 50 years on this green technology, many challenges remain, including the use of metal-containing catalysts for polymerization, the removal of the chromatic metal residue after polymerization, and the limited practicable epoxides, especially for those containing electron-withdrawing groups. Herein, we provide kinds of pinwheel-shaped tetranuclear organoboron catalysts for epichlorohydrin/CO2 copolymerization with >99% polymer selectivity and quantitative CO2 uptake (>99% carbonate linkages) under mild conditions (25-40 °C, 25 bar of CO2). The produced poly(chloropropylene carbonate) has the highest molecular weight of 36.5 kg/mol and glass transition temperature of 45.4 °C reported to date. The energy difference (ΔEa = 60.7 kJ/mol) between the cyclic carbonate and polycarbonate sheds light on the robust performance of our metal-free catalyst. Control experiments and density functional theory (DFT) calculations revealed a cyclically sequential copolymerization mechanism. The metal-free feature, high catalytic performance under mild conditions, and no trouble with chromaticity for the produced polymers imply that our catalysts are practical candidates to advance the CO2-based polycarbonates.

14.
ACS Appl Mater Interfaces ; 13(3): 4583-4592, 2021 Jan 27.
Article in English | MEDLINE | ID: mdl-33448218

ABSTRACT

A salt-responsive nanoplatform is constructed through a simple tactic by tethering zwitterionic nanohydrogels (NGs) on a carboxylated silica (SiO2-COOH) framework. Chondroitin sulfate (CS), with a specific recognition effect for low-density lipoprotein (LDL), is modified to NGs by amidation reaction. Water retention and swelling properties of NGs are greatly enhanced in a saline environment attributed to the anti-polyelectrolyte effect. It endows the SiO2-NGs-CS framework a sensitive salt-responsive property, and thus, more CS moieties are exposed. The controlled adsorption of LDL with an adsorption efficiency of 7.2 to 93% is achieved by adjusting the concentration of MgCl2 from 0 to 0.1 mol L-1. SiO2-NGs-CS exhibits excellent adsorption capacity for fishing LDL, acquiring the highest adsorption capacity of 898.1 mg g-1. Moreover, SiO2-NGs-CS shows superior selectivity to the other three proteins with similar isoelectric points (pIs) to LDL. The captured LDL is readily stripped by 0.2% (m/m) SDS with a recovery of 95.4%. The superior separation performance of SiO2-NGs-CS is demonstrated by the isolation and selective discrimination of LDL from the simulated serum of hypercholesterolemia patients, as illustrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis assays.


Subject(s)
Chondroitin Sulfates/chemistry , Hydrogels/chemistry , Lipoproteins, LDL/isolation & purification , Nanogels/chemistry , Silicon Dioxide/chemistry , Adsorption , Animals , Cattle , Electrophoresis, Polyacrylamide Gel , Humans , Lipoproteins, LDL/blood , Magnesium Chloride/chemistry
15.
Anal Chim Acta ; 1147: 144-154, 2021 Feb 22.
Article in English | MEDLINE | ID: mdl-33485572

ABSTRACT

Zr-based metal-organic framework, UiO-66-NH2, provides favorable adsorption capacity to phosphoproteins, however, it exhibits obvious nonspecific adsorption to other proteins. In the present work, we report a facile strategy to reduce the nonspecific adsorption of nonphosphoproteins by modifying UiO-66-NH2 with imidazolium ionic liquids (ILs). With respect to bare UiO-66-NH2, the modified counterpart, UiO@IL, exhibits much improved selectivity to phosphoproteins while maintains comparable adsorption performance. The surface of UiO@IL presents a strong hydrophilicity due to the modification of ILs. Hydrophobic and electrostatic interaction between the absorbent and nonphosphoprotein is significantly reduced. In addition, the interaction between imidazole group of ILs moiety and phosphate group in phosphoprotein ensures the favorable adsorption capacity of UiO@IL for phosphoproteins. Anionic moieties of ILs, i.e., Cl-, Br-, BF4-, CF3SO3-, play negligible effect in the adsorption process. As a representative, phosphoprotein ß-casein (ß-ca) is selectively enriched at a mass ratio of BSA:ß-ca = 100:1. UiO@IL was further applied for the selective enrichment of phosphoprotein in milk.


Subject(s)
Ionic Liquids , Metal-Organic Frameworks , Adsorption , Anions , Phosphoproteins
16.
PLoS Negl Trop Dis ; 14(12): e0008951, 2020 12.
Article in English | MEDLINE | ID: mdl-33332355

ABSTRACT

The excretory-secretory products released by the liver fluke Fasciola gigantica (FgESPs) play important roles in regulating the host immune response during the infection. Identification of hepatic miRNAs altered by FgESPs may improve our understanding of the pathogenesis of F. gigantica infection. In this study, we investigated the alterations in the hepatic microRNAs (miRNAs) in mice treated with FgESPs using high-throughput small RNA (sRNA) sequencing and bioinformatics analysis. The expression of seven miRNAs was confirmed by quantitative stem-loop reverse transcription quantitative PCR (qRT-PCR). A total of 1,313 miRNAs were identified in the liver of mice, and the differentially expressed (DE) miRNAs varied across the time lapsed post exposure to FgESPs. We identified 67, 154 and 53 dysregulated miRNAs at 1, 4 and 12 weeks post-exposure, respectively. 5 miRNAs (miR-126a-3p, miR-150-5p, miR-155-5p, miR-181a-5p and miR-362-3p) were commonly dysregulated at the three time points. We also found that most of the DE miRNAs were induced by FgESPs in the mouse liver after 4 weeks of exposure. These were subjected to Gene Ontology (GO) enrichment analysis, which showed that the predicted targets of the hepatic DE miRNAs of mice 4 weeks of FgESPs injection were enriched in GO terms, including cell membrane, ion binding, cellular communication, organelle and DNA damage. KEGG analysis indicated that the predicted targets of the most downregulated miRNAs were involved in 15 neural activity-related pathways, 6 digestion-related pathways, 20 immune response-related pathways and 17 cancer-related pathways. These data provide new insights into how FgESPs can dysregulate hepatic miRNAs, which play important roles in modulating several aspects of F. gigantica pathogenesis.


Subject(s)
Computational Biology , Fasciola/genetics , Fascioliasis/parasitology , MicroRNAs/genetics , Animals , Down-Regulation , Female , High-Throughput Nucleotide Sequencing , Immunity , Liver/parasitology , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction
17.
Angew Chem Int Ed Engl ; 59(51): 23291-23298, 2020 Dec 14.
Article in English | MEDLINE | ID: mdl-32869449

ABSTRACT

A series of highly active organoboron catalysts for the coupling of CO2 and epoxides with the advantages of scalable preparation, thermostability, and recyclability is reported. The metal-free catalysts show high reactivity towards a wide scope of cyclic carbonates (14 examples) and can withstand a high temperature up to 150 °C. Compared with the current metal-free catalytic systems that use mol % catalyst loading, the catalytic capacity of the catalyst described herein can be enhanced by three orders of magnitude (epoxide/cat.=200 000/1, mole ratio) in the presence of a cocatalyst. This feature greatly narrows the gap between metal-free catalysts and state-of-the-art metallic systems. An intramolecular cooperative mechanism is proposed and certified on the basis of investigations on crystal structures, structure-performance relationships, kinetic studies, and key reaction intermediates.

18.
Orthop Surg ; 12(4): 1074-1083, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32686337

ABSTRACT

OBJECTIVE: To examine the results of raloxifene for prevention of periprosthetic bone loss around the femoral stem in patients undergoing total hip arthroplasty (THA). METHODS: Between January 2015 and May 2017, 240 female patients between 55 and 80 years underwent primary THA and were randomly allocated to receive 60 mg raloxifene hydrochloride per day (treatment group, TG, n = 120) or placebo (control group, CG, n = 120) orally at bedtime using computer-generated randomization sequence generation. Baseline data, the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), women's quality of life (QoL) score, bone mineral density (BMD) around the prosthesis, and adverse events were compared between the two groups. The measuring range of BMD around the prosthesis was divided into seven regions of interest (ROI). The sample size was calculated to detect a mean difference in BMD of 0.15 g/cm2 with a standard deviation (SD) of 0.3. The error was set at 0.05 and the power level at 90% with additional compensation for a possible dropout rate of 20%. RESULTS: A total of 240 participants in the study up to 24 months after THA. There were no significant differences in the mean BMD of all the zones between groups before surgery (all P > 0.05). However, there were significant differences in the BMD of Gruen zones 4 and 7 between groups at 6 months postoperatively (both P < 0.05); there were significant differences in Gruen zones 1, 4, 6, and 7 at 12 months postoperatively (all P < 0.01); there were significant differences in Gruen zones 1, 2, 4, 6, and 7 at 24 months postoperatively (all P < 0.001). Patients taking raloxifene reported higher QoL scores, with better improvement in BMD in all areas except in zones 3 and 5 compared with the control group. There were no significant differences in WOMAC pain (P = 0.4045), WOMAC function (P = 0.4456) and women's QoL scores (P = 0.5983) between groups before surgery. However, WOMAC pain, WOMAC function and women's QoL score in the treatment group were significantly better at all time points (all P < 0.05). Patients in the treatment group showed no increased adverse events, including cardiac events, stroke, venous thromboembolism, and gynecological cancer (all P > 0.05), but did show decreased odds of breast cancer in comparison with those using a placebo (P = 0.0437). CONCLUSION: Raloxifene can help inhibit bone loss around the prosthesis and improve the QoL of postmenopausal women after THA with no increased adverse events, and can even decrease the odds of breast cancer.


Subject(s)
Arthroplasty, Replacement, Hip , Bone Resorption/prevention & control , Osteoporosis/prevention & control , Postmenopause , Postoperative Complications/prevention & control , Raloxifene Hydrochloride/therapeutic use , Aged , Aged, 80 and over , Bone Density Conservation Agents/therapeutic use , Disability Evaluation , Double-Blind Method , Female , Humans , Middle Aged , Prospective Studies , Quality of Life
19.
ChemSusChem ; 13(16): 4121-4127, 2020 Aug 21.
Article in English | MEDLINE | ID: mdl-32662576

ABSTRACT

The development of solvent-free, metal-free, recyclable organic catalysts is required for the current chemical fixation of carbon dioxide converted into cyclic carbonates. With the goal of reducing the cost, time, and energy consumption for the coupling reaction of CO2 and epoxides, a series of highly active heterogeneous catalysts, based on a thiourea and quaternary ammonium salt system, are synthesized by using a thiol-ene click reaction under ultraviolet light. Benefitting from synergistic interactions of the electrophilic center (thiourea) and the nucleophilic site (ammonium bromide), the catalysts exhibit excellent catalytic selectivity (99 %) for the cycloaddition of carbon dioxide with a diverse range of epoxides under mild conditions (1.2 MPa, 100 °C). Moreover, the catalyst can be easily recycled by facile filtration and reused for 5 times without noticeable loss of activity and selectivity. This work provides a potential heterogeneous catalyst for the conversion of carbon dioxide into high value-added chemicals with the combined advantages of low cost, easy recovery, and satisfactory catalytic properties.

20.
Schizophr Res Cogn ; 22: 100182, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32577406

ABSTRACT

OBJECTIVE: To illustrate the influence of clinical variables on cognition performance in patients with schizophrenia (SCZ). METHODS: Using the 66nao Brain Training device (a novel measurement tool), the cognitive performance of 99 patients with SCZ was evaluated. Patients were diagnosed by the ICD-10 diagnostic criteria for SCZ, and their age were 16-68 years old. Furthermore, we explored the relationship between age, biomedical variables and specific cognitive domains in patients with SCZ. Patients were divided into two groups: various of cognitive domains impairment group and non-impairment group according to the norm scores. All data were analyzed using RStudio Version 1.0.44 (RStudio, Inc.). RESULTS: Patients with SCZ had obvious cognitive impairment in total and five subdomains of cognitive function. We found that 1) SCZ patients with impaired cognitive total score experienced significant older age and longer illness duration compared with those with normal cognitive total score. 2) SCZ patients with impaired memory experienced significant older age compared with those with normal memory. 3) SCZ patients with impaired attention showed significant lower serum triglyceride (TG) level compared with those with normal attention. 4) SCZ patients with impaired flexibility performed significant longer illness duration compared with those with normal flexibility. 5) SCZ patients with impaired cognitive agility performed significant older age, longer duration, and higher systolic blood pressure (SBP) compared with those with normal cognitive agility. 6) The age, illness duration and SBP in patients with impaired time perception were marginally different from those of subjects with normal time perception. CONCLUSION: There are five dimensions (memory, attention, flexibility, cognitive agility, and time perception) of cognitive dysfunction in SCZ patients. Age, illness duration, TG, and SBP might play vital roles in various subdomains of the cognitive deficits respectively in patients with SCZ.

SELECTION OF CITATIONS
SEARCH DETAIL
...