Copper-Catalyzed Umpolung Reactivity of Propargylic Carbonates in the Presence of Diboronates: One Stone Four Birds.

Allylation and propargylation are two powerful synthetic strategies for making new substances that have been of significant importance in chemistry, medicine, and material fields. Conventional tactics employ various preformed allylation and propargylation reagents. In this study, a conceptually novel copper-catalyzed and B2pin2-mediated Umpolung reactivity of propargylic carbonates has been achieved for the first time, realizing both allylation and propargylation of aldehydes and ketones without additional reductants. Three types of allylation products and one type of propargylation product are generated efficiently, and all allylation products are formed with syn-configurations predominantly. The choice of ligands plays a vital role in modulating the Umpolung modes. The synthetic applications have been demonstrated in a myriad of further transformations including natural product synthesis, and systematic mechanistic studies have been conducted to reveal detailed insights into the Umpolung processes.

NHPI-Mediated Electrochemical α-Oxygenation of Amides to Benzimides.

This report describes a mild electrochemical α-oxygenation of a wide range of linear and cyclic benzamides mediated by N-hydroxyphthalimide (NHPI) in an undivided cell using O2 as the oxygen source and 2,4,6-trimethylpyridine perchlorate as an electrolyte. The radical scavenger experiment and the 18O labeling experiment were carried out, which indicated the involvement of a radical pathway and suggested O2 as an oxygen source in the imides, respectively.

Preparation and Characterization of Phenolic Acid-Chitosan Derivatives as an Edible Coating for Enhanced Preservation of Saimaiti Apricots.

In this study, caffeic acid (CA) and chlorogenic acid (CGA) were incorporated onto chitosan (CS) using free radical grafting initiated by a hydrogen peroxide/ascorbic acid (H2O2/Vc) redox system. The structural properties of the CA (CA-g-CS) and CGA (CGA-g-CS) derivatives were characterized by UV-Vis absorption, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and thermal stability analysis. Then, the antioxidant and antibacterial properties were evaluated, and the effect of CGA-g-CS on the postharvest quality of Saimaiti apricot was studied. It proved that phenolic acids were successfully grafted onto the CS. The grafting ratios of CA-g-CS and CGA-g-CS were 126.21 mg CAE/g and 148.94 mg CGAE/g. The antioxidation and antibacterial activities of CGA-g-CS were better than those of CA-g-CS. The MICs of CGA-g-CS against E. coli, S. aureus, and B. subtilis were 2, 1, and 2 mg/mL. The inhibitory zones of 20 mg/mL CGA-g-CS against the three bacteria were 19.16 ± 0.35, 16.33 ± 0.91, and 16.24 ± 0.05 mm. The inhibitory effects of 0.5% CGA-g-CS on the firmness, weight loss, SSC, TA, relative conductivity, and respiration rate of the apricot were superior. Our results suggest that CGA-g-CS can be potentially used as an edible coating material to preserve apricots.

Selective Electrochemical Oxygenation of Alkylarenes to Carbonyls.

An efficient electrochemical method for benzylic C(sp3)-H bond oxidation has been developed. A variety of methylarenes, methylheteroarenes, and benzylic (hetero)methylenes could be converted into the desired aryl aldehydes and aryl ketones in moderate to excellent yields in an undivided cell, using O2 as the oxygen source and lutidinium perchlorate as an electrolyte. On the basis of cyclic voltammetry studies, 18O labeling experiments, and radical trapping experiments, a possible single-electron transfer mechanism has been proposed for the electrooxidation reaction.

The tumor phototherapeutic application of nanoparticles constructed by the relationship between PTT/PDT efficiency and 2,6- and 3,5-substituted BODIPY derivatives.

BODIPY dyes have recently been used for photothermal and photodynamic therapy of tumors. However, complex multi-material systems, multiple excitation wavelengths and the unclear relationship between BODIPY structures and their PTT/PDT efficiency are still major issues. In our study, nine novel BODIPY near-infrared dyes were designed and successfully synthesized and then, the relationships between BODIPY structures and their PTT/PDT efficiency were investigated in detail. The results showed that modifications at position 3,5 of the BODIPY core with conjugated structures have better effects on photothermal and photodynamic efficiency than the modifications at position 2,6 with halogen atoms. Density functional theory (DFT) calculations showed that this is mainly due to the extension of the conjugated chain and the photoinduced electron transfer (PET) effect. By encapsulating BDPX-M with amphiphilic DSPE-PEG2000-RGD and lecithin, the obtained NPs not only show good water solubility and biological stability, but also could act as superior agents for photothermal and photodynamic synergistic therapy of tumors. Finally, we obtained BODIPY NPs that exhibited excellent photothermal and photodynamic effects at the same time under single irradiation with an 808 nm laser (photothermal conversion efficiency: 42.76%, A/A0: ∼0.05). In conclusion, this work provides a direction to design and construct phototherapeutic nanoparticles based on BODIPY dyes for tumor treatment.

Correlations between blood lipid, serum cystatin C, and homocysteine levels in patients with Parkinson's disease.

AIM: The aim was too study the correlations between blood lipid, serum cystatin C (Cys C) and homocysteine (Hcy) levels in patients with Parkinson's disease (PD). METHODS: A total of 322 PD patients and 214 healthy subjects were selected as case and control groups, respectively. The risk factors were explored by logistic regression analysis. The case group was subtyped according to main motor symptoms and age of onset. The correlations of significantly different indices with age, duration of disease, and equivalent dose of levodopa were studied by Spearman's correlation analysis. Receiver operating characteristic curves were plotted to analyze diagnostic values. RESULTS: Compared to the control group, the PD group had lower serum total cholesterol, triglyceride, and apolipoprotein B (Apo B) levels and higher high-density lipoprotein cholesterol (HDL-C), Hcy, and Cys C levels (P < 0.05). Decreased Apo B level and increased HDL-C and Hcy levels were independent risk factors (P < 0.05). The Cys C level of early-onset patients was lower than of late-onset patients (P < 0.05). Hcy (r = 0.198, P < 0.05) and Cys C (r = 0.281, P < 0.05) levels were positively correlated with age. Triglyceride level was negatively correlated with age (r = -0.202, P < 0.05) and disease duration (r = -0.198, P < 0.05). Unified Parkinson's Disease Rating Scale III score was positively correlated with disease duration (r = 0.435, P < 0.05) and equivalent dose of levodopa (r = 0.423, P < 0.05). The areas under the curve for Apo B, HDL-C, and Hcy levels were 0.341, 0.588, and 0.643, respectively (P < 0.05). The combination of Apo B, HDL-C, and Hcy levels showed high diagnostic value, with a sensitivity of 76.4% and specificity of 69.5%. CONCLUSIONS: Low serum levels of total cholesterol, triglyceride, and Apo B, and high levels of HDL-C, Hcy, and Cys C may be correlated with PD onset and progression. Decreased Apo B level and elevated HDL-C and Hcy levels are independent risk factors. Early-onset and late-onset PD may have different progression mechanisms.

Aberrantly expressed long noncoding RNAs and genes in Parkinson's disease.

PURPOSE: Parkinson's disease (PD) is a common neurodegenerative movement disorder, but the pathogenesis remains elusive. This study was aimed to explore key genes and long noncoding RNAs (lncRNAs) associated with PD. MATERIALS AND METHODS: Three patients with PD and three normal controls were enrolled in the present study from July 12, 2017, to August 29, 2017. RNA sequencing and bioinformatics analysis were performed to obtain differentially expressed micro RNAs (DEmRNAs) and lncRNAs (DElncRNAs) between patients with PD and normal controls. PD-specific protein-protein interaction networks were constructed. DEmRNAs transcribed within a 100 kb window upstream or downstream of DElncRNAs were searched, which were defined as cis nearby targeted DEmRNAs of DElncRNAs. Datasets GSE57475 and GSE68719 were downloaded from the Gene Expression Omnibus database, which were used to validate the expression of selected DEmRNAs. RESULTS: A total of 857 DEmRNAs and 77 DElncRNAs were obtained between PD and normal controls. Natural killer cell-mediated cytotoxicity was a significantly enriched pathway in PD. ERBB2, HSPB1, and MYC were three hub proteins of PD-specific protein-protein interaction network. LOC105378701-TAL1, LOC102724104-CX3CR1, LOC105375056-TREML1/TREML4, LOC105379392-ANK1, and LOC101928100-KLRK1/KLRD1 interactions were identified DElncRNA nearby targeted DEmRNA pairs in PD. Gene expression results validated by GSE57475 and GSE68719 were consistent with our RNA-sequencing results, generally. CONCLUSION: This present study identified key genes and lncRNAs associated with PD, which will provide new clues for exploring the pathogenesis and developing potential biomarkers of PD.

Effects of serum N-terminal pro B-type natriuretic peptide and D-dimer levels on patients with acute ischemic stroke.

OBJECTIVE: To detect the serum levels of D-dimer and N-terminal pro B-type natriuretic peptide (NT-pro BNP) in patients with Acute Ischemic Stroke (AIS), and to explore the risk factors of AIS. METHODS: A total of 246 AIS patients treated in our hospital from January 2015 to January 2017 were selected. Meanwhile, 240 healthy subjects were selected as a control group. The D-dimer and NT-pro BNP levels of the two groups were compared. Correlations of such levels with age, gender, blood lipid, Intima-Media Thickness (IMT), fibrinogen and degree of neurological deficits were analyzed. RESULTS: The AIS group had significantly higher levels of Triglyceride (TG), Low-Density Lipoprotein (LDL), D-dimer, NT-pro BNP and fibrinogen as well as IMT than those of the control group, but the High-Density Lipoprotein (HDL) level of the AIS group was significantly lower (P<0.05). The patients with different genders and ages had significantly different D-dimer and NT-pro BNP levels (P<0.05). The D-dimer and NT-pro BNP levels were correlated with gender and age. Such levels of females were significantly higher than those of males (P<0.05). The D-dimer and NT-pro BNP levels of the ≥60 years old group significantly exceeded those of the <60 years old group (P<0.05). The levels of D-dimer and NT-pro BNP were negatively correlated with that of HDL (P<0.05), but positively correlated with TG, LDL and fibrinogen levels, IMT, and National Institutes of Health Stroke Scale score (P<0.05). Multivariate Logistic regression analysis showed that the OR values of D-dimer and NT-pro BNP were 3.65 and 6.96 respectively. CONCLUSION: Serum D-dimer and NT-pro BNP levels usually increased in AIS patients, and the levels were significantly correlated with AIS onset.

The self-assembly of monosubstituted BODIPY and HFBI-RGD.

A novel fluorescent probe was constructed by the self-assembly of monosubstituted BODIPY and a novel targeted hydrophobin named hereafter as HFBI-RGD. Optical measurements and theoretical calculations confirmed that the spectral properties of the probe were greatly influenced by the BODIPY structure, the appropriate volume of BODIPY and the cavity of HFBI-RGD. The experiments in vivo and ex vivo demonstrated that the probe had excellent ability for tumor labelling.

N-Heterocyclic carbene-catalyzed sulfa-Michael addition of enals.

An efficient N-heterocyclic carbene (NHC) catalyzed sulfa-Michael addition (SMA) between enals and thiols has been developed. Under the catalysis of 10 mol% stable free carbene IPr and with 20 mol% hexafluoroisopropanol (HFIP) as an additive, enals react with a variety of thiols to afford the SMA adducts in 54-98% yields. In this process, the free carbene preferentially interacts with thiols through hydrogen-bonding and no NHC-catalyzed extended Umpolung transformations were observed.

N-Heterocyclic carbene-catalyzed stereoselective construction of olefinic carbon-sulfur bonds via cross-coupling reaction of gem-difluoroalkenes and thiols.

A novel organocatalytic olefinic carbon-sulfur bond forming reaction was developed. Under the catalysis of 10 mol% stable N-heterocyclic carbene, thiols undergo direct nucleophilic substitution reaction with gem-difluoroalkenes to produce α-fluorovinyl thioethers in high yields with excellent Z-selectivity. In this process, bases are not necessary.

Changes in Olfactory Bulb Volume in Parkinson's Disease: A Systematic Review and Meta-Analysis.

OBJECTIVE: The changes in olfactory bulb (OB) volume in Parkinson's disease (PD) patients have not yet been comprehensively evaluated. The purpose of this meta-analysis was to explore whether the OB volume was significantly different between PD patients and healthy controls. METHODS: PubMed and Embase were searched up to March 6, 2015 with no language restrictions. Two independent reviewers screened eligible studies and extracted data on study characteristics and OB volume. Additionally, a systematic review and meta-analysis using a random-effects model were conducted. Publication bias was determined by using funnel plots and Begg's and Egger's tests. Subgroup analyses were performed to assess possible sources of heterogeneity. RESULTS: Six original case-control studies of 216 PD patients and 175 healthy controls were analyzed. The pooled weighted mean difference (WMD) in the OB volume between the PD patients and the healthy participants was -8.071 for the right OB and -10.124 for the left OB; these values indicated a significant difference among PD patients compared with healthy controls. In addition, a significant difference in the lateralized OB volume was observed in PD patients, with a pooled WMD of 1.618; these results indicated a larger right OB volume than left OB volume in PD patients. In contrast, no difference in the lateralized OB volume was found in healthy controls. No statistical evidence of publication bias among studies was found based on Egger's or Begg's tests. Sensitivity analyses revealed that the results were consistent and robust. CONCLUSIONS: Overall, both the left and the right OB volume were significantly smaller in PD patients than in healthy controls. However, significant heterogeneity and an insufficient number of studies underscore the need for further observational research.

Analysis of catechol-O-methyltransferase gene mutation and identification of new pathogenic gene for paroxysmal kinesigenic dyskinesia.

We aimed to analyze the mutation site and frequency of catechol-O-methyltransferase (COMT) gene, to explore the relationship between COMT genotype and phenotype, and to find new pathogenic genes for paroxysmal kinesigenic dyskinesia (PKD). PKD patients who were treated from December 2011 to January 2014 were selected and subjected to genetic testing in the exon region of COMT. Two patients and one intrafamilial healthy control were subjected to exome sequencing using whole exome capture in combination with high-throughput sequencing to find candidate pathogenic gene sites. The results were verified by Sanger sequencing. A total of 11 familial PKD patients from 4 families and 9 sporadic patients without family history were included. Pathogenic c.634dupC(p.P220fsX7) mutation of COMT gene was found in 7 familial PKD patients and3 sporadic patients. Mutated COMT gene carriers suffered from PKD earlier (average age of onset: 11.61 ± 2.33 vs 16.21 ± 2.58, P = 0.001) with symmetric symptoms in most cases, while the mutation-negative group only showed unilateral symptoms (P = 0.001). The mutation-positive group also had more daily attacks (P = 0.038). Carbamazepine worked for all mutation-positive patients (10/10, 100%), but only for a part of mutation-negative patients (3/10, 30.0%). About 90000 single nucleotide polymorphisms and 2000 insertion-deletion polymorphisms were detected in each of the three samples. c.737C → T(p.T246 M) mutation of POC1B gene was a new pathogenic site for a selected family. COMT gene mutation, which was the pathogenesis of most familial PKD patients and a part of sporadic patients, predicted the response to carbamazepine. POC1B may be a novel pathogenic gene for PKD.

Comparative study on the antioxidant activities of extracts of Coreopsis tinctoria flowering tops from Kunlun Mountains, Xinjiang, north-western China.

Coreopsis tinctoria flowering tops (CTFs) from the Kunlun Mountains in Xinjing (north-western China) have been used for tea production for about a century. This study aims to assess the antioxidant activities and total phenolic, flavonoid and proanthocyanidin contents of various solvent extracts of CTF. CTF was extracted using n-hexane, chloroform, ethyl acetate, n-butanol, 75% aqueous ethanol (AEE) and water. The antioxidant activities of the CTF extracts were investigated through DPPH, ABTS, *OH, *O2(-), total antioxidant capacity and reducing power assays. The results showed that n-butanol extract showed the highest contents of total phenols and flavonoids, with DPPH, ABTS and *OH radical-scavenging activities with IC50 values of 134, 90.72 and 13.8 µg mL(-1), respectively. The AEE demonstrated the strongest DPPH and ABTS radical-scavenging activities, with IC50 values of 103 and 75.16 µg mL(-1), respectively. Given its high antioxidant effect, CTF is a good source of natural antioxidants or functional food materials.

Chemical composition, N-nitrosamine inhibition and antioxidant and antimicrobial properties of essential oil from Coreopsis tinctoria flowering tops.

Coreopsis tinctoria flowering (CTF) tops from the Kunlun Mountains in Xinjing (north-western China) have been used for tea production for about a century. This study was to assess antioxidant, nitrite-scavenging and N-nitrosamine inhibitory and antimicrobial activities of the essential oil extracted from CTF tops. The essential oil was extracted through hydrodistillation and its chemical compositions were analysed by GC-MS. Seventy compounds of the oil were identified, representing 81.87% of total oil. The antioxidant capacities of the oil with IC50 values for scavenging DPPH and ABTS were 287.66 ± 12.60 and 1.251 ± 0.127 µg mL(- 1), respectively. The nitrite-scavenging and N-nitrosamine inhibitory activities (IC50) were 0.3912 ± 0.0127 and 0.6564 ± 0.036 µg mL(- 1), respectively. The oil has a certain antimicrobial capacity, but its capacity was weaker than that of penicillinG (24 µg mL(- 1)). The oil showed antioxidant and antimicrobial capacities and had a stronger nitrite-scavenging and N-nitrosamine inhibitory properties.

Two new cucurbitane-type triterpenoid saponins isolated from ethyl acetate extract of Citrullus colocynthis fruit.

Two new cucurbitacins I (1 and 2), together with eight known compounds (3-10), were isolated from the ethyl acetate extract of the fruit of Citrullus colocynthis. Compounds 3, 5-9 were isolated from C. colocynthis for the first time. The structures of new compounds were determined primarily from IR, HR-MS, 1D-, and 2D-NMR analysis.

Photodegradation of nitrobenzene using 172 nm excimer UV lamp.

Photodegradation of nitrobenzene (NB) using an excimer UV lamp at a wavelength of 172 nm is investigated. Experimental results show that high concentration nitrobenzene can be efficiently degraded with irradiation by excimer UV lamp, and confirm that degradation of nitrobenzene is more efficient by UV/H(2)O(2) combination than UV only. In the case of using UV only, 60 min of treatment was found to be sufficient to degrade the major part of NB solution with a concentration of less than 4mM. In the case of using the combination of UV/H(2)O(2) with a H(2)O(2) concentration of 7:1 molar ratio to NB, 4.07 mM NB solution drastically decreased to 0.41 mM after treatment for only 20 min. Degradation intermediate products are identified by analyzing the degradation products with GC/HRMS and possible degradation pathways of nitrobenzene are suggested.