Here we report the first palladium‐catalyzed asymmetric hydrogenolysis of readily available aryl triflates via desymmetrization and kinetic resolution for facile construction of axially chiral biaryl ...scaffolds with excellent enantioselectivities and s selectivity factors. The axially chiral monophosphine ligands could be prepared from these chiral biaryl compounds and were further applied to palladium‐catalyzed asymmetric allylic alkylation with excellent ee values and high branched and linear ratio, which demonstrated the potential utility of this methodology.
We have developed the first palladium‐catalyzed asymmetric hydrogenolysis of aryl triflates through desymmetrization and kinetic resolution that allows the facile construction of axially chiral biaryl scaffolds with excellent results. These chiral compounds could be further converted into chiral monophosphine ligands, which were then used in asymmetric allylic alkylation to produce the desired product with high regio‐ and enantioselectivities.
Different types of cancer exhibit distinct gene expression profiles. The present study aimed to identify a specific gene dysregulated in hepatocellular carcinoma (HCC) that was essential for cancer ...progression. The whole transcriptomes of primary HCC tissue samples were analyzed with microarrays. The most significantly differentially expressed gene was identified, specifically karyopherin subunit-α 2 (KPNA2), and an analysis using the Oncomine online tool was performed with data from The Cancer Genome Atlas to predict associated genes in HCC. Reverse transcription-quantitative polymerase chain reaction was performed to confirm the gene expression levels of KPNA2, and the RNA interference knockdown of KPNA2 was performed to identify the effect on putative downstream target genes. A proliferation assay and flow cytometry analysis was used to assess the function of KPNA2 in the regulation of the cell cycle. The results demonstrated that KPNA2 expression was significantly upregulated in HCC tumor tissues compared with liver tissues and was associated with cyclin B2 (CCNB2) and cyclin-dependent kinase 1 (CDK1) expression. KPNA2 expression was identified a novel marker to predict the outcome of patients. In addition, KPNA2 knockdown downregulated CCNB2 and CDK1, inhibited cell proliferation and induced cell cycle arrest in the G
/M phase. In conclusion, it was demonstrated that KPNA2 may promote tumor cell proliferation by increasing the expression of CCNB2/CDK1. KPNA2 could be a target for therapeutic intervention in HCC.
To investigate the interaction and erosion mechanisms between an ultrahigh-pressure water jet and the surface of Grade A marine steel, this study used the ANSYS FLUENT software to simulate the ...hydrodynamic characteristics of an ultrahigh-pressure water jet. To erode the Grade A marine steel, a water jet with ultrahigh-pressure (200 MPa, 40 L/min) was used. An ASMC2-4 resistance strain gauge collected the dynamic strain signal at the back of the sample during jet impingement, and the simulation results were compared to experimental results. A scanning electron microscope (SEM), X-ray diffractometer (XRD), energy dispersive spectrometer (EDS), and other equipment were used to observe and analyze the phase before impact and the material surface morphology and element distribution after impact. The results reveal that as the wall shear stress increased with the target distance, the energy loss of the jet could be reduced by changing the jet incidence angle, and the peak value of the wall shear stress increased. Under the pressure of 200 MPa, the average microstrain at the back side of the impact center area of the Grade A marine steel was 180 × 10−6, and the microstrain amplitude was 35 × 10−6–50 × 10−6. The impact force of the water jet on the Grade A marine steel produced alternating stress with cyclic fluctuation. The experimental results are consistent with the simulation results. Under the alternating jet stress action, fatigue failure and cavitation failure occurred on the sample surface, which was characterized by a spalling pit, layer erosion, and cavitation hole morphology. The surface stripping model of the Grade A marine steel under an ultrahigh-pressure water jet was established, and the interaction mechanism and erosion mechanism between the ultrahigh-pressure water jet and the surface of the Grade A marine steel were elucidated.
Alzheimer's disease (AD) is a severe neurodegenerative disorder without curative treatment. Extensive data on pathological molecular processes have been accumulated over the last years. These data ...combined allows a systems biology approach to identify key regulatory elements of AD and to establish a model descriptive of the disease process which can be used for the development of therapeutic agents. In this study, the authors propose a closed network that uses a set of nodes (amyloid beta, tau, beta-secretase, glutamate, cyclin-dependent kinase 5, phosphoinositide 3-kinase and hypoxia-induced factor 1 alpha) as key elements of importance to the pathogenesis of AD. The proposed network, in total 39 nodes, is able to become a novel tool capable of providing new insights into AD, such as feedback loops. Further, it highlights interconnections between pathways and identifies their combination for therapy of AD.
Abstract Objectives The objectives of this study are to introduce the surgical technique of a modified spiral orthotopic ileal neobladder and to assess the long-term outcomes. Patients and methods ...Between January 1998 and January 2006, 44 male and 7 female patients with bladder cancer received radical cystectomy (RC) and pelvic lymphadenectomy. An ileal segment 40 cm to 45 cm long was isolated to create a spiral orthotopic ileal neobladder, and the ureters were implanted into the reservoir using a non-refluxing split-cuff nipple technique. Preoperative, perioperative, and postoperative data were collected. Complications were classified as early (less than 3 months after surgery) or late (more than 3 months after surgery). Continence incidence and urodynamic studies were evaluated 5 years after surgery. Duration of follow-up was an average of 95 months (range 60–156 months). Results There were no perioperative deaths. The mean operative time was 315 ± 34 minutes. The mean blood loss was 783 ± 316 ml. There were 31 early complications in 21 patients (41%) and 42 late complications in 30 patients (59%). Urodynamic studies showed the maximum neobladder capacity to be 500 ± 71 ml, maximum flow rate to be 16 ± 5 ml/s and post-voiding residual (PVR) to be 50 ± 44 ml. Postoperative continence was excellent with a daytime continence rate of 90% and a nocturnal continence rate of 78% 5 years after surgery. Conclusions The modified spiral neobladder is easy to perform and allows for excellent long-term results with regard to complications and continence.
Here we report the first palladium‐catalyzed asymmetric hydrogenolysis of readily available aryl triflates via desymmetrization and kinetic resolution for facile construction of axially chiral biaryl ...scaffolds with excellent enantioselectivities and s selectivity factors. The axially chiral monophosphine ligands could be prepared from these chiral biaryl compounds and were further applied to palladium‐catalyzed asymmetric allylic alkylation with excellent ee values and high branched and linear ratio, which demonstrated the potential utility of this methodology.
We have developed the first palladium‐catalyzed asymmetric hydrogenolysis of aryl triflates through desymmetrization and kinetic resolution that allows the facile construction of axially chiral biaryl scaffolds with excellent results. These chiral compounds could be further converted into chiral monophosphine ligands, which were then used in asymmetric allylic alkylation to produce the desired product with high regio‐ and enantioselectivities.
There are remarkable disparities among patients of different races with prostate cancer; however, the mechanism underlying this difference remains unclear. Here, we present a comprehensive landscape ...of the transcriptome profiles of 14 primary prostate cancers and their paired normal counterparts from the Chinese population using RNA-seq, revealing tremendous diversity across prostate cancer transcriptomes with respect to gene fusions, long noncoding RNAs （long ncRNA）, alternative splicing and somatic mutations. Three of the 14 tumors （21.4%） harbored a TM- PRSS2-ERG fusion, and the low prevalence of this fusion in Chinese patients was further confirmed in an additional tumor set （10/54=18.5%）. Notably, two novel gene fusions, CTAGE5-KHDRBS3 （20/54=37%） and USP9Y-TTTY15 （19/54=35.2%）, occurred frequently in our patient cohort. Further systematic transcriptional profiling identified nu- merous long ncRNAs that were differentially expressed in the tumors. An analysis of the correlation between expres- sion of long ncRNA and genes suggested that long ncRNAs may have functions beyond transcriptional regulation. This study yielded new insights into the pathogenesis of prostate cancer in the Chinese population.
Chlorinated paraffins（SCCPs） are widely used worldwide, and they can be released into the environment during their production, transport, usage and disposal, which pose potential risks for human ...health. In this work, an efficient, reliable and rapid pretreatment method based on matrix solid-phase dispersion（MSPD） was developed for the analysis of short-chain CPs（SCCPs） in human placenta by gas chromatograph-electron capture negative ion low-resolution mass spectrometry（GC-ECNI-LRMS） and gas chromatography–quadrupole time-of-flight mass spectrometry（GC–QTOF-HRMS）. The MSPD-relevant parameters including dispersing sorbent,sample-to-sorbent mass ratio, and elution solvent were optimized using the orthogonal test.Silica gel was found to be the optimal dispersing sorbent among the selected matrices. Under the optimal conditions, 44% acidic silica gel can be used as the co-sorbent to remove lipid and eluted by the mixture of hexane and dichloromethane（7：3, V/V）. The spiked recoveries of the optimized method were 77.4% and 91.4% for analyzing SCCPs in human placenta by GC-ECNI-LRMS and GC–QTOF-HRMS, and the corresponding relative standard deviations were10.2% and 5.6%, respectively. The method detection limit for the total SCCPs was 36.8 ng/g（dry weight, dw） and 19.2 ng/g（dw） as measured by GC-ECNI-LRMS and GC–QTOF-HRMS,respectively. The concentrations of SCCPs in four human placentas were in the range of
Many studies have focused on various agricultural management measures to reduce agricultural nitrous oxide （N2O） emission. However, few studies have investigated soil N2O emissions in intercropping ...systems in the North China Plain. Thus, we conducted a ifeld experiment to compare N2O emissions under monoculture and maize-legume intercropping systems. In 2010, ifve treatments, including monocultured maize （M）, maize-peanut （MP）, maize-alfalfa （MA）, maize-soybean （MS）, and maize-sweet clover （MSC） intercropping were designed to investigate this issue using the static chamber technique. In 2011, M, MP, and MS remained, and monocultured peanuts （P） and soybean （S） were added to the trial. The results showed that total production of N2O from different treatments ranged from （0.87＆#177;0.12） to （1.17＆#177;0.11） kg ha-1 in 2010, while those ranged from （3.35＆#177;0.30） to （9.10＆#177;2.09） kg ha-1 in 2011. MA and MSC had no signiifcant effect on soil N2O production compared to that of M （P＆lt;0.05）. Cumulative N2O emissions from MP in 2010 were signiifcantly lower than those from M, but the result was the opposite in 2011 （P＆lt;0.05）. MS signiifcantly reduced soil N2O emissions by 25.55 and 48.84%in 2010 and 2011, respectively （P＆lt;0.05）. Soil N2O emissions were signiifcantly correlated with soil water content, soil temperature, nitriifcation potential, soil NH4＋, and soil NO3-content （R2=0.160-0.764, P＆lt;0.01）. A stepwise linear regression analysis indicated that soil N2O release was mainly controlled by the interaction between soil moisture and soil NO3-content （R2=0.828, P＆lt;0.001）. These results indicate that MS had a coincident effect on soil N2O lfux and signiifcantly reduced soil N2O production compared to that of M over two growing seasons.
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