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To expand the application field of PVC and make PVC resin high-performance, much research has been done on the toughening modification of PVC at home and abroad. ACR tougheners with different core-shell ratios were prepared by core-shell emulsion polymerization, which was used to blend PVC resin. In the experiment, the tensile and impact properties of PVC/ACR blends were tested and the fracture morphology was observed. The impact properties of PVC blends with toughened particles with different core-shell ratios were investigated and compared with the commercial ACR-401 toughener. The best combination of toughening effect was obtained: when the PVC/ACR blend ratio was 100:3.5, the tensile strength of PVC toughened by ACR7030 core-shell particles was 22.78MPa, and the impact strength was 8.67 kJ/m, which was superior to the commercial ACR-401 toughener. Therefore, ACR7030 can significantly enhance the mechanical properties of PVC, and the toughened PVC shows ductile fracture.

A systematically chemical investigation of Citrus changshan-huyou Y.B. Chang resulted in the isolation and structure determination of twelve known natural products, including limonoid ( 1 ), nootkatone ( 2 ), scoparone ( 3 ), β-sitosterol ( 4 ), 3,5,6,7,8,3',4'-heptamethoxyflavone ( 5 ), nobiletin ( 6 ), tangeretin ( 7 ), naringin ( 8 ), hesperidin ( 9 ), neohesperidin ( 10 ), 3,5-dihydroxyphenyl β-D-glucoside ( 11 ), β-sitosterol-D-glucoside ( 12 ). The structure modification of the most abundant compound limonin ( 1 ) further led to eight limonoid derivatives, including epi -limonol ( 1a ), epi -limonyl acetate ( 1b ), and six new compounds epi -limonol A ( 1c ), limonol A ( 1d ), limonol B ( 1e ), epi -limonol B ( 1f ), epi -limonol C ( 1g ), epi -limonol D ( 1h ), which enlarged the chemical diversity of limonin related limonoids. The structures of the new limonoid derivatives were identified by extensive spectroscopic analysis. In bioassay, all the isolates, the semi-synthetic derivatives and the previously isolated limonoids ( 13 - 20 ) in our natural product library were subjected for anti-inflammatory activities evaluation, and several limonoids exhibited the inhibition of TNF-α release.

Background This study will investigate the effect of shikonin on the proliferation and apoptosis of human ovarian cancer cell SKOV3 (HOCC-SKOV3). Methods We will retrieve potential studies from inception to the March 1, 2020 in Cochrane Library, MEDLINE, EMBASE, Scopus, Cumulative Index to Nursing and Allied Health Literature, WANGFANG, and China National Knowledge In-frastructure. There are not restrictions related to the language and publication status. This study will include case-controlled studies (CCSs) or randomized controlled studies (RCSs) that examine the effect of shikonin on the proliferation and apoptosis of HOCC-SKOV3. Two researchers will independently identify literatures, extract data, and appraise study quality. Any disagreements will be resolved by discussion with another researcher. RevMan 5.3 software will be placed to perform statistical analysis. Results This study will summarize the present evidence to test the effect of shikonin on the proliferation and apoptosis of HOCC-SKOV3. Conclusion It will provide evidence to investigate the effect of shikonin on the proliferation and apoptosis of HOCC-SKOV3, and will supply reference for further study.Systematic review registration: INPLASY202040146.

A chiral ionic liquid (CIL) moiety of a l-pyrrolidin-2-ylimidazole-decorated homochiral UiO-68-type metal–organic framework, UiO-68-CIL (1), was successfully prepared by the combination of a new premodified chiral CIL ligand (H2L-CIL) and ZrCl4 via a solvothermal method. The TiO2-loaded TiO2@UiO-68-CIL (2) was prepared by impregnating 1 in a toluene solution of Ti(OPri)4 and sequential in situ hydrolysis. The obtained 2 can be a bifunctional asymmetric heterogeneous catalyst to successfully promote the one-pot Morita–Baylis–Hillman reaction starting from aromatic alcohols in a tandem way.

A CuI-loaded and n-pentadecyl-attached imidazolium salt decorated UiO-67-type metal–organic framework (CuI@UiO-67-IM, 2) based on a new premodified ligand L (n-pentadecyl-attached imidazolium (IM) decorated dicarboxylic acid) and ZrCl4 is reported. Compound 2 can be a bifunctional composite heterogeneous phase-transfer catalyst to promote the azide–alkyne cycloaddition (H2O, air, 80 °C) from corresponding halogenated compounds and sodium azide as a sequential one-pot procedure with high yields and excellent regioselectivity.

Objective To explore the protective effect of trimetazidine on the myocardial tissue of rats by observing the oxidative stress, apoptosis and energy metabolism in myocardial tissue of rats after exhausted exercise. Methods Thirty healthy adult male Wistar rats were randomly assigned to three groups (10 each): quiet control group (C), exhausted exercise group (E) and exhausted exercise plus trimetazidine group (TE). Exhausted exercise model was established by forcing the rats swim ceaselessly, rats in group TE received hydrochloric acid trimetazidine (10mg/kg) for intervention. The myocardial tissue of rats was collected after the last exhausted exercise. The myocardial tissue of rats was evaluated by HE staining. The concentrations of superoxide dismutase (SOD), glutathione peroxidase 1 (GSH-Px) and malondialdehyde (MDA) in rats' myocardial cell mitochondria were detected by spectrophotometry. RT-PCR and immunohistochemistry were performed to quantify the mRNA and protein levels of Bax, Bcl-2 and uncoupling protein 2 (UCP2) in myocardial tissue of rats. Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling (TUNEL) assay was employed to detect the apoptotic rate of myocardial tissue. Results Compared with group C, the SOD and GSH-Px activities in groups E and TE were reduced (P

A chiral ionic liquid (CIL) moiety of a l-pyrrolidin-2-ylimidazole-decorated homochiral UiO-68-type metal-organic framework, UiO-68-CIL (1), was successfully prepared by the combination of a new premodified chiral CIL ligand (H

Two copper-loaded MOF materials, namely Cu(II)@Ui-O-66-NH2 (1) and Cu(0)@UiO-66-NH2 (2), are reported. They can, respectively, serve as highly efficient heterogeneous catalysts for olefin oxidation and hydrogenation under mild conditions. Complete styrene hydrogenation occurs in 15 min at ambient temperature with quantitative yield.

We aimed to characterize postpartum disease flares among treatment-naive mothers with chronic hepatitis B (CHB). CHB mothers were enrolled and compared with non-infected mothers in terms of postpartum alanine aminotransferase (ALT) abnormalities. Demographic, virological, and biochemical parameters were collected up to postpartum week 16, with flares and exacerbations defined as ALT levels 5–10 and >10 times the upper limit of normal, respectively. Outcome assessments included ALT flares or exacerbation and their predictive parameters. Among 4236 patients enrolled, 869 and 3367 had no infection (group A) and had CHB (group B), respectively. Infected mothers were further stratified into two subgroups by the presence (B1, n = 1928) or absence (B2, n = 1439) of detectable serum levels of hepatitis B virus (HBV) DNA (lowest level of quantitation, 100 IU/mL). A significantly higher frequency of abnormal ALT levels was observed in group B vs. group A (28.27 vs. 20.37%, p

Background: Ovarian cancer (OC) is one of the most leading causes of deaths in the Chinese women. The objective of this protocol is to perform a full-scale systematic review on the efficacy of weekly cisplatin (WC) for the treatment of patients with OC. Methods: Data sources will comprise of PubMed, PsycINFO, Scopus, Opengrey, Cochrane Central Register of Controlled Trials, Embase, Cumulative Index to Nursing and Allied Health Literature, Web of Science, Allied and Complementary Medicine Database, and Chinese Biomedical Literature Database. All relevant randomized controlled trials from searched databases will be identified from their inception to the present. A defined search strategy will be implemented along with eligibility criteria. Relevant data will be extracted according to the predefined data collection form. Methodologic quality will be assessed by using Cochrane risk of bias tool; and data pooled and meta-analysis will be conducted by using fixed-effects, or random-effects model with RevMan 5.3 software. Results: This proposed systematic review will evaluate the efficacy of WC for patients with OC. Conclusion: The findings of this study may summarize the latest evidence for the WC on OC. Ethics and dissemination: Ethical approval is not required for this study, because it will be based on published studies, and existing sources of literature. The results of this study will be disseminated through peer-reviewed journal. PROSPERO registration number: PROSPERO CRD42018120938.

Two copper-loaded MOF materials, namely Cu(ii)@Ui-O-66-NH

A robust and porous Cd(II)-MOF based on a bent imidazole-bridged ligand was synthesized and post-synthetically functionalized with linear alkyl chains to afford imidazolium salt (IM)-type triphase transfer catalysts for organic transformations. The imidazolium salt decorated Cd(II)-MOF-IM exhibits typical solid phase transfer catalytic behavior for the azidation and thiolation of bromoalkane between aqueous/organic phases. Moreover, they can be easily recovered and reused under the PTC conditions. Cd(II)-MOF-IM herein created a versatile family of solid phase transfer catalysts for promoting a broad scope of reactions carried out in a biphasic mixture of two immiscible solvents.