Discovery, characterization and mechanism of a Microbacterium esterase for key d-biotin chiral intermediate synthesis.

Esterases are crucial biocatalysts in chiral compound synthesis. Herein, a novel esterase EstSIT01 belonging to family V was identified from Microbacterium chocolatum SIT101 through genome mining and phylogenetic analysis. EstSIT01 demonstrated remarkable efficiency in asymmetrically hydrolyzing meso-dimethyl ester [Dimethyl cis-1,3-Dibenzyl-2-imidazolidine-4,5-dicarboxyate], producing over 99% yield and 99% enantiomeric excess (e.e.) for (4S, 5R)-monomethyl ester, a crucial chiral intermediate during the synthesis of d-biotin. Notably, the recombinant E. coli expressing EstSIT01 exhibited over 40-fold higher activity than that of the wild strain. EstSIT01 displays a preference for short-chain p-NP esters. The optimal temperature and pH were 45 °C and 10.0, with Km and kcat values of 0.147 mmol/L and 5.808 s- 1, respectively. Molecular docking and MD simulations suggest that the high stereoselectivity for meso-diester may attribute to the narrow entrance tunnel and unique binding pocket structure. Collectively, EstSIT01 holds great potential for preparing chiral carboxylic acids and esters.

Ir(III)-catalyzed quadruple C-H activation of N-arylimidazolium and diaryliodonium salts: facile access to polysubstituted imidazo[1,2-f]phenanthridiniums.

Herein, N-heterocyclic carbene-directed Ir(III)-catalyzed cascade C-H arylation/annulation of N-arylimidazolium with diaryliodonium salts has been accomplished for the first time via a quadruple C-H activation strategy to construct imidazo[1,2-f]phenanthridinium structures. This protocol overcomes the compatibility of three kinds of different C-H activations with high catalytic efficiency, which allows ortho-unhindered N-arylimidazoliums to undergo a diarylation/annulation reaction, affording a variety of polysubstituted imidazo[1,2-f]phenanthridiniums. Neutral imidazo[1,2-f]phenanthridines are also prepared via a demethylation reaction of imidazo[1,2-f]phenanthridiniums.

Planar Tetraindolodipleiadiene via Zirconium-Promoted Intramolecular Indolyl C4-H Homocoupling.

A novel N-rimmed PAH molecule containing a dipleiadiene core (TIDP) was designed and synthesized from indole, wherein a ZrCl4-promoted intramolecular C4-H homocoupling reaction of the indole moieties was the key approach. TIDP exhibited a nearly full planar structure and antiaromaticity of the two embedded heptagonal rings. The extremely stable radical cation TIDP•+·PF6- was isolated quantitatively by oxidation with AgPF6.

Thioether-Assisted Cu-Catalyzed C5-H Arylation of Imidazo[1,5-a]pyridines.

A Cu-catalyzed regioselective C5-H arylation of imidazo[1,5-a]pyridines with aryl iodides was achieved with the assistance of an ethylthio group at the C3 position. This directing group could be easily removed to furnish a range of 5-(hetero)arylimidazo[1,5-a]pyridine derivatives. The reaction tolerates a variety of functionalities and is compatible with sterically hindered substrates.

Ni(II)-catalyzed C-H hydroarylation of diarylacetylenes with imidazolium salts.

A simple Ni(II)-catalyzed C-H hydroarylation of diarylacetylenes with imidazolium salts without adding any ligand was developed. It provides a facile and efficient access to (E)-2-(1,2-diarylvinyl)imidazolium salts. The preliminary results indicate a rare nonredox catalytic cycle of Ni(II), complementary to the common redox catalytic cycle starting from Ni(0).

Red fluorescent zwitterionic naphthalenediimides with di/mono-benzimidazolium and a negatively-charged oxygen substituent.

The C-H/C-X cross-coupling of a benzimidazolium salt with 2Br-NDI afforded two unprecedented zwitterionic NDIs with di/mono-benzimidazolium and an extra negatively-charged oxygen substituent. They exhibited intensified red fluorescence in polar solvents and negative solvatochromism due to an intramolecular charge transfer process, and could specifically label lysosomes and the endoplasmic reticulum in living A549 cells, respectively. They represent a rare case of NDI-derived ionic fluorophores.

CCT5 interacts with cyclin D1 promoting lung adenocarcinoma cell migration and invasion.

Cyclin D1 (CCND1) has been identified as a metastatic promoter in various tumors including lung adenocarcinoma (LUAD), a subtype of non small cell lung cancer (NSCLC). The previous observation revealed that CCND1 was upregulated in NSCLC and predicted poor prognosis of LUAD patients. In this study, we examined a chaperonin containing TCP1 subunit 5 (CCT5) protein interacts with CCND1 in LUAD. Immunofluorescence demonstrated the co-localization of CCT5 and CCND1 protein in LUAD cells. CCT5 expression was detected with both immunohistochemistry (IHC) and bioinformatics analyses. Similar with the expression pattern of CCND1, CCT5 displayed a high level in LUAD tissues compared to non cancerous lung specimens. Patients with high CCT5 expression showed a significant shorter overall survival relative to those with low expression level. Furthermore, upregulated CCT5 exhibited significant positive correlation with TNM stage of LUAD patients in both IHC analyses and bioinformatics. Knocking down CCT5 remarkably inhibited LUAD cell migration and invasion in vitro by inactivating PI3K/AKT and its downstream EMT signals, which could abrogated the accelerated migration and invasion caused by CCND1 overexpression. In summary, our study discovered a highly expressed protein CCT5 in LUAD which interacted with CCND1 and promoted migration and invasion of LUAD cells by positively moderating PI3K/AKT-induced EMT pathway.

Fentanyl inhibits acute myeloid leukemia differentiated cells and committed progenitors via opioid receptor-independent suppression of Ras and STAT5 pathways.

Fentanyl is a common sedative/analgesic used for intrathecal chemotherapy injection in children with acute leukemia. Given the contradictory findings that fentanyl has both inhibitory and stimulatory activities in cancer cells, we investigated the biological effects of fentanyl alone and its combination with standard of care in acute myeloid leukemia (AML) cells at all stages of development. We showed that fentanyl at clinically relevant concentration inhibited growth and colony formation of AML differentiated cells and committed progenitors without affecting their survival. Compared to AML cells without FLT3 mutation, cells harboring FLT3-ITD mutation are likely to be more sensitive to fentanyl. However, fentanyl did not affect the most primitive AML stem cells. Fentanyl significantly augmented the efficacy of cytarabine but not midostaurin in AML differentiated cells and committed progenitors. We further demonstrated that fentanyl inhibited AML cells via suppressing Ras/Raf/MEK/ERK and STAT5 pathway, and this was not dependent on opioid receptor system. Our findings demonstrate the anti-leukemia activity of fentanyl and synergistic effects between fentanyl and cytarabine in AML, via opioid receptor-independent suppression of Ras and STAT5 pathways. Our work is the first to suggest the beneficial effects of fentanyl in children with leukemia.

MiR-559 targets GP73 to suppress proliferation and invasion of hepatocellular carcinoma in vitro.

Hepatocellular carcinoma (HCC) is one of the common malignant tumors with poor overall prognosis. As a tumor suppressor, the function of miR-559 in HCC is not clear. In this study, quantitative real-time PCR was carried out to measure the expression of miR-559 in HCC cell lines. The effects of miR-559 on HCC cell proliferation, migration, and invasion were evaluated through a series of functional assays. The mechanism through which miR-559 regulates HCC cells was investigated by dual-luciferase reporter assay and functional experiments. The results revealed that miR-559 expression was low in HCC cell lines. Upregulation of miR-559 suppressed HCC cell proliferation, migration, and invasion. Dual-luciferase reporter assay confirmed Golgi membrane protein 73 (GP73) as a target gene of miR-559. Moreover, miR-559 could negatively regulate GP73 expression in HCC cells. These results demonstrated that low-level expression of miR-559 was associated with HCC, and overexpression of miR-559 could inhibit HCC cell growth and invasion via targeting GP73.

LncRNA LINC00152 Promotes Laryngeal Cancer Progression by Sponging MiR-613.

BACKGROUND: Long noncoding RNA (lncRNA) LINC00152 (CYTOR) has been reported to be upregulated and to serve as a diagnostic biomarker in multiple types of cancers, including laryngeal squamous cell cancer (LSCC). However, the functional role and molecular mechanisms of LINC00152 in LSCC progression need to be further investigated. METHODS: LINC00152 levels in LSCC and adjacent normal tissues were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Gene knockdown of LINC00152 was achieved in LSCC cells by use of small interfering RNA (siRNA). Cell proliferation, apoptosis, migration and invasion were examined by a series of methods. The micoRNA (miRNA) interaction with LINC00152 was screened by starBase v2.0 and confirmed by luciferase reporter activity. RESULTS: LINC00152 levels in LSCC tissues were significantly higher than those in adjacent normal tissue, and patients with lymph node metastasis or an advanced clinical stage displayed higher LINC00152 expression. Moreover, siRNA-mediated LINC00152 knockdown significantly inhibited the proliferation, migration and invasion of LSCC cells and induced apoptosis in those cells. Mechanistically, LINC00152 functioned as a competing endogenous RNA (ceRNA) sponging miR-613. The inhibitory effect of LINC00152 knockdown on malignant behavior was abrogated by inhibiting miR-613. CONCLUSION: LINC00152 exerts an oncogenic effect on the tumorigenesis of LSCC by sponging miR-613 and may serve as a potential target for treating LSCC.

Meta-Analysis of Efficacy and Safety of Tadalafil Plus Tamsulosin Compared with Tadalafil Alone in Treating Men with Benign Prostatic Hyperplasia and Erectile Dysfunction.

This meta-analysis was performed to evaluate the efficacy and safety of tadalafil plus tamsulosin compared with tadalafil alone in treating men with benign prostatic hyperplasia (BPH) and erectile dysfunction (ED) after 12 weeks' treatment. Systematic review was carried out using the Preferred Reporting Items for Systematic Reviews and Meta-analyses. MEDLINE, EMBASE, and the Cochrane Controlled Trials Register were searched to collect randomized controlled trials. The references of related articles were also searched. Four articles including 621 patients were involved in the analysis. The study identified that combination-therapy had significant improvements in total international prostate symptom score (IPSS), quality of life (QoL) and maximum urine flow rate (Qmax) compared with monotherapy, and there were no obvious significance in respects of post-void residual volume, international index of erectile function and IPSS storage. The difference of total IPSS was mainly reflected in the change of IPSS voiding. For safety, combination-therapy had a higher incidence rate of any adverse events (AEs) and discontinuation due to AEs than monotherapy with the exception of pain. In conclusion, the combination of tadalafil and tamsulosin provided a better improvement of IPSS voiding, QoL and Qmax compared with tadalafil alone in treating men with BPH and ED, and the former therapy appeared to show a higher incidence of AEs.

Synthesis of a Double-Helical Naphthotetraindole Core via an Intramolecular Dehydrogenative Homocoupling Reaction.

A novel naphthotetraindole (NTI) core was synthesized in two steps via the McMurry reaction and a [Cu]/[Ag]-promoted intramolecular dehydrogenative homocoupling reaction. NTI shows a unique X-shaped double-helical structure as determined by single-crystal X-ray diffraction analysis. The hole-transport mobility of the bare NTI core was measured to be 2.3 × 10-5 cm2 V-1 s-1, which is comparable with the commonly used Spiro-OMeTAD.

Two-Fold C-H/C-H Cross-Coupling Using RhCl3·3H2O as the Catalyst: Direct Fusion of N-(Hetero)arylimidazolium Salts and (Hetero)arenes.

[Cp*RhCl2]2 is the most prevailing catalyst employed for rhodium-catalyzed chelation-assisted C-H/C-H cross-coupling reactions due to the special ligand effect of Cp*. In this article, a novel concept of using a simple inorganic rhodium salt, RhCl3·3H2O, as the catalyst by taking advantage of in situ π-coordination to Rh with a (hetero)aromatic reaction component to stabilize Rh intermediates is proposed and evaluated. Our studies not only prove the feasibility of this concept but also disclose a novel 2-fold C-H/C-H cross-coupling reaction of N-(hetero)arylimidazolium salts with various (hetero)arenes to access water-soluble, fluorescent, cationic, and planar polycyclic heteroaromatic molecules, in which RhCl3·3H2O outperforms [Cp*RhCl2]2. Mechanistic experiments and DFT calculations reveal that this successive quadruple C-H activation reaction consists of two different C-H activation modes, i.e., concerted metalation-deprotonation (CMD) and oxidative addition. Notably, this is the first report of a C-H bond activation via oxidative addition to RhI in a bi(hetero)aryl formation with hydrogen evolution. Finally, the different ligand electrochemical parameters of neutral (hetero)arenes and anionic Cp* are used to explain the different catalytic behaviors of RhCl3·3H2O and [Cp*RhCl2]2.

[Meta-analysis of the condylar position with mandibular deviation].

PURPOSE: This study was aimed to analyze the differences of condylar position between the mandibular deviation and the individual normal occlusion. METHODS: Databases of PubMed,Embase,CNKI ,Wanfang ,VIP and CBL were searched for the relevant articles about condylar position with mandibular deviation. The deadline was June 2017.Data quality evaluation and extraction were independently conducted by two authors. Then meta analysis was performed using Rev Man 5.3 software. RESULTS: Six articles on controlled study of the condylar position in patients with mandibular deviation and individuals with normal occlusion were included. 122 patients had mandibular deviation and 110 had normal occlusion. Meta analysis results showed that the condylar superior space[MD=-0.38,95%CI(-0.74,-0.01),P=0.04]and anterior space[MD=-0.72,95%CI(-0.99,-0.04),P＜0.00001]of the deviation side in mandibular deviation group were significantly greater than that of the opposite side; The condylar posterior space[MD=-0.35,95%CI(0.25,0.45),P＜0.00001]of the deviation side in mandibular deviation group was significantly smaller than that of the opposite side. The condylar posterior space of deviation side[MD=-0.58,95%CI(-0.88,-0.28),P=0.0002],opposite side[MD=-0.30,95%CI(-0.59,-0.00),P=0.05] and the anterior space of opposite side[MD=-0.85,95%CI(-1.58,-0.13),P=0.02] in the mandibular deviation group was significantly smaller than that in the individuals with normal occlusion; the differences were statistically significant. There was no significant difference in the condylar superior space between the deviation side[MD=-0.56,95%CI(-1.14,0.02),P=0.06] and the opposite side[MD=-0.58,95%CI(-1.27,0.10),P=0.10] and the anterior space[MD=-0.05,95%CI(-0.35,0.46),P=0.80]in deviation side in the mandibular deviation group ,comparing with individuals with normal occlusion. CONCLUSIONS: The condylar position of deviation side in patients with mandibular deviation is posterior and inferior, comparing with the opposite side. The condylar position of deviation side in patients with mandibular deviation is posterior, comparing with the individuals with normal occlusion.

Tandem Rh-Catalyzed [4 + 2] Vinylic C-H O-Annulation of Exocyclic Enones with Alkynes and 1,5-H Shift.

Active pyrylium intermediates are in situ generated by a Rh-catalyzed vinylic C-H annulation reaction between exocyclic α,ß-enones and alkynes, which undergo a base-promoted rearrangement via 1,5-H shift to form 1H-benzo[f]chromene derivatives.

Iridium-Catalyzed Direct Regioselective C4-Amidation of Indoles under Mild Conditions.

An efficient Ir-catalyzed amidation of indoles with sulfonyl azides is disclosed, affording diverse C4-amidated indoles exclusively under mild conditions. In this protocol, a variety of indoles with commonly occurring functional groups such as formyl, acetyl, carboxyl, amide, and ester at the C3 position are well tolerated.

Rh/Cu-Catalyzed Cascade [4+2] Vinylic C-H O-Annulation and Ring Contraction of α-Aryl Enones with Alkynes in Air.

An unprecedented Rh-catalyzed ketone-directed vinylic C-H activation/[4+2] O-annulation of α-aryl enones with internal alkynes followed by a Cu-catalyzed ring contraction in air to provide multiaryl-substituted furan derivatives has been developed. The preliminary mechanism study identifies the active pyrylium salt as the key intermediate.

[Analysis the relationship of mean platelet volume and obstructive sleep apnea and hypopnea syndrome].

OBJECTIVE: Uur aim was to investigate the association between OSAHS and mean platelet volume (MPV) value. METHOD: This study included 70 cases with OSAHS in our ward between Jan. 2012 and Jan. 2014, and the OSAHS patients were divided two groups: mild- to moderate group and severe group; 30 age-and sex-matched healthy subjects was in control group. The correlation among the levels of the number of platelets (PLT), MPV, platelet distribution width (PDW) were evaluated in the two groups. RESULT: PLT count was significantly lower in the severe group than the control group [(202. 8 ± 68. 9] × 10(9)/L, (235. 9 ± 65. 2) × 10(9)/L]; MPV and PDW were significantly higher in the severe group [(10. 9 ± 0. 9), (10. 4±0. 8) fL; (12. 9 ± 1. 9) %, (12. 0 ± 1. 4) %]. There was not significantly difference of MPV between the mild to moderate group and the control group [(10. 7 ± 0. 7), (10. 4 ± 0. 8)fL]. CONCLUSION: MPV levels are elevated in patients with the severe OSAHS.

Can routine oral care with antiseptics prevent ventilator-associated pneumonia in patients receiving mechanical ventilation? An update meta-analysis from 17 randomized controlled trials.

BACKGROUND: Whether oral antiseptics could reduce the risk of ventilator associated pneumonia (VAP) in patients receiving mechanical ventilation remains controversial. We performed a meta-analysis to assess the effect of oral care with antiseptics on the prevalence of ventilator associated pneumonia in adult critically ill patients. METHODS: A comprehensive search of PubMed, Embase and Web of Science were performed to identity relevant studies. Eligible studies were randomized controlled trials of mechanically ventilated adult patients receiving oral care with antiseptics. The quality of included studies was assessed by the Jadad score. Relative risks (RRs), weighted mean differences (WMDs), and 95% confidence intervals (CIs) were calculated and pooled using a fixed-effects model or random-effects model. Heterogeneity among the studies was assessed with I (2) test. RESULTS: 17 studies with a total number of 4249 met the inclusion criteria. Of the 17 studies, 14 assessed the effect of chlorhexidine, and 3 investigated the effect of povidone-iodine. Overall, oral care with antiseptics significantly reduced the prevalence of VAP (RR=0.72, 95% CI: 0.57, 0.92; P=0.008). The use of chlorhexidine was shown to be effective (RR=0.73, 95% CI: 0.57, 0.93; P=0.012), whereas this effect was not observed in povidone-iodine (RR=0.51, 95% CI: 0.09, 2.82; P=0.438). Subgroup analyses showed that oral antiseptics were most marked in cardiac surgery patients (RR=0.54, 95% CI: 0.39, 0.74; P=0.00). Patients with oral antiseptics did not have a reduction in intensive care unit (ICU) mortality (RR=1.11, 95% CI: 0.95, 1.29; P=0.201), length of ICU stay (WMD=-0.10 days, 95% CI: -0.25, 0.05; P=0.188), or duration of mechanical ventilation (WMD=-0.05 days, 95% CI: -0.14, 0.04; P=0.260). CONCLUSION: Oral care with antiseptics significantly reduced the prevalence of VAP. Chlorhexidine application prevented the occurrence of VAP in mechanically ventilated patients but povidone-iodine did not. Further large-scale, well-designed randomized controlled trials are needed to identify the findings and determine the effect of povidone-iodine application.

Copper response of Proteus hauseri based on proteomic and genetic expression and cell morphology analyses.

The copper response of Proteus hauseri ZMd44 was determined using one-dimensional (1D) gel electrophoresis coupled with MALDI-TOF-TOF mass spectrometry for a similarity analysis of proteins isolated from P. hauseri ZMd44 cultured in CuSO4-bearing LB medium. Candidate proteins identified as a copper-transporting P-type ATPase (CTPP), phosphoenolpyruvate carboxykinase (PEPCK), flagellin (Fla), and outer membrane proteins (Omps) were the major copper-associated proteins in P. hauseri. In a comparative analysis of subcellular (i.e., periplasmic, intracellular, and inner membranes) and cellular debris, proteomics analysis revealed a distinct differential expression of proteins in P. hauseri with and without copper ion exposure. These findings were consistent with the transcription level dynamics determined using quantitative real-time PCR. Based on a genetic cluster analysis of copper-associated proteins from P. hauseri, Fla and one of the Omps showed greater diversity in their protein sequences compared to those of other Proteus species. Transmission electron microscopy (TEM) and the observed growth on LB agar plates showed that the swarming motility of cells was significantly suppressed and inhibited upon Cu(II) exposure. Thus, copper stress could have important therapeutic significance due to the loss of swarming motility capacity in P. hauseri, which causes urinary tract infections.