Over the past decade, N-heterocycliccarbene (NHc), bipyridine (bpy), and pyridine oxazoline (PyOx) ligands have been increasingly applied in nickel catalysis, where the combination of a low-oxidation-state 3d metal a...
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Over the past decade, N-heterocycliccarbene (NHc), bipyridine (bpy), and pyridine oxazoline (PyOx) ligands have been increasingly applied in nickel catalysis, where the combination of a low-oxidation-state 3d metal and an electron-rich ligand can enable otherwise challenging bond activations. Herein we report the synthesis and characterization of two Ni(0) complexes supported by an alternative, bidentate, c,N ligand, (h)IMesPy ("half-IMes-pyridine" or 1-(2,4,6-trimethylphenyl)-3-(2-pyridinyl)-imidazol-2-ylidene). The unsymmetric ligand combines the strong sigma-donating properties of an NHc with the pi-accepting properties of pyridine to afford homoleptic [Ni((h)IMesPy)(2)] and heteroleptic [Ni(cod)((h)IMesPy)] complexes. characterization through the combination of single-crystal X-ray diffraction analysis and NMR spectroscopy, as well as reactivity studies demonstrating reversible interconversion between the two species, provide a strong basis for future applications to overcome reactivity challenges.
The mechanisms of the Rh(I)-catalyzed alkenylation reaction were investigated by density functional theory (DFT) calculations. Our results show that the c-H activation of this reaction occurs through the metal hydride...
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The mechanisms of the Rh(I)-catalyzed alkenylation reaction were investigated by density functional theory (DFT) calculations. Our results show that the c-H activation of this reaction occurs through the metal hydride pathway rather than the general concerted metalation deprotonation (cMD) mechanism. The favorable metal -hydride pathway involves c-H oxidative addition, alkyne migratory insertion into Rh-H and c-c reductive elimination. Moreover, the consecutive migratory insertion into the Rh-H and c-c reductive elimination is kinetically more favorable than the alkyne migratory insertion into Rh-c and c-H reductive elimination. The cMD pathway is kinetically unfavorable due to the considerably higher barrier of several elementary steps. The improved mechanistic understanding will enable design of novel couplings between hydrocarbons and c-H bonds.
During mitosis, phosphorylation and dephosphorylation of lamins triggers the nuclear envelope disassembly/assembly. However, it hasn't been known whether lamin proteins undergo any modification other than phosphor...
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During mitosis, phosphorylation and dephosphorylation of lamins triggers the nuclear envelope disassembly/assembly. However, it hasn't been known whether lamin proteins undergo any modification other than phosphorylation during the cell cycle. Glycosylation of lamin proteins is one of the less studied post-translational modification. Glycosylation and phosphorylation compete for the same positions and interplay between two modifications generate a post-translational code in the cell. Based on this, we hypothesized that glycosylation of lamin A/c protein may be important in the regulation of the structural organization of the nuclear lamina during interphase and mitosis. We analysed the glycan units of lamin A/c protein in lung carcinoma cells synchronized at G2/M and S phases via capLc-ESI-MS/MS. Besides, the outermost glycan units were determined using lectin blotting and gold-conjugated antibody and lectin staining. TEM studies also allowed us to observe the localization of glycosylated lamin A/c protein. With this study, we determined that lamin A/c protein shows O-glycosylation at G2/M and S phases of the cell cycle. In addition to O-GlcNAcylation and O-GalNAcylation, lamin A/c is found to be contain Gal, Fuc, Man, and Sia sugars at G2/M and S phases for the first time. Having found the glycan units of the lamin A/c protein suggests that glycosylation might have a role in the nuclear organization during the cell cycle.
Introduction coagulopathy and thrombosis associated with SARS-coV-2 infection are well defined in hospitalized adults and leads to adverse outcomes. Pediatric studies are limited. Methods An international multicentere...
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Introduction coagulopathy and thrombosis associated with SARS-coV-2 infection are well defined in hospitalized adults and leads to adverse outcomes. Pediatric studies are limited. Methods An international multicentered (n = 15) retrospective registry collected information on the clinical manifestations of SARS-coV-2 and multisystem inflammatory syndrome (MIS-c) in hospitalized children from February 1, 2020 through May 31, 2021. This sub-study focused on coagulopathy. Study variables included patient demographics, comorbidities, clinical presentation, hospital course, laboratory parameters, management, and outcomes. Results Nine hundred eighty-five children were enrolled, of which 915 (93%) had clinical information available;385 (42%) had symptomatic SARS-coV-2 infection, 288 had MIS-c (31.4%), and 242 (26.4%) had SARS-coV-2 identified incidentally. Ten children (1%) experienced thrombosis, 16 (1.7%) experienced hemorrhage, and two (0.2%) experienced both thrombosis and hemorrhage. Significantly prevalent prothromboticcomorbidities included congenital heart disease (p-value .007), respiratory support (p-value .006), central venous catheter (cVc) (p = .04) in children with primary SARS-coV-2 and in those with MIS-c included respiratory support (p-value .03), obesity (p-value .002), and cytokine storm (p = .012). comorbidities prevalent in children with hemorrhage included age >10 years (p = .04), cVc (p = .03) in children with primary SARS-coV-2 infection and in those with MIS-c encompassed thrombocytopenia (p = .001) and cytokine storm (p = .02). Eleven patients died (1.2%), with no deaths attributed to thrombosis or hemorrhage. conclusion Thrombosis and hemorrhage are uncommon events in children with SARS-coV-2;largely experienced by those with pre-existing comorbidities. Understanding the complete spectrum of coagulopathy in children with SARS-coV-2 infection requires ongoing research.
Introduction Posttransplant diabetes mellitus (PTDM) can increase morbidity and mortality in liver transplant recipients. Although hepatitis c seropositivity is a known risk factor for PTDM, the impact of viremia vers...
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Introduction Posttransplant diabetes mellitus (PTDM) can increase morbidity and mortality in liver transplant recipients. Although hepatitis c seropositivity is a known risk factor for PTDM, the impact of viremia versus no viremia at time of transplant is unknown. Project Aims This program evaluation sought to compare PTDM in hepatitis c seropositive patients with and without viremia at the time of liver transplant. Design This single-center retrospective review included adult hepatitis c seropositive liver transplant recipients transplanted between January 1, 2010 to September 5, 2017 without pretransplant diabetes. Primary outcome was PTDM within 1 year. Secondary outcomes included evaluating 1-year posttransplant death-censored graft loss, mortality, and metabolic outcomes. Results Fifty-seven liver transplant recipients with hepatitis c were included, of which 53% (n = 30) were viremic at transplant. Baseline characteristics were similar between groups. Significantly more patients with pretransplant viremia developed PTDM by 1-year posttransplant compared to the patients without viremia (43% vs 11%, P = 0.01). There were no differences between groups outside of more patients with viremia requiring antihypertensives by 1-year posttransplant compared to patients without viremia (57% vs 22%, P = 0.01). conclusion Liver transplant patients with hepatitis c viremia at transplant were more likely to develop PTDM at 1 year compared to those without pretransplant viremia. This is an added consideration when deciding the timing of direct-acting antiviral (DAA) utilization in the context of liver transplant for hepatitis c seropositive patients.
In this cluster cross-over randomized trial in 5 in-patient cancer/transplant units neither clostridioides difficilenor vancomycin-resistant enterococci (VRE) transmission rates were reduced by UV-c light disinfection...
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In this cluster cross-over randomized trial in 5 in-patient cancer/transplant units neither clostridioides difficilenor vancomycin-resistant enterococci (VRE) transmission rates were reduced by UV-c light disinfection when used in patients' rooms daily and at time of discharge. Background Our objective was to determine if the addition of ultraviolet-c (UV-c) light to daily and discharge patient room cleaning reduces healthcare-associated infection rates of vancomycin-resistant enterococci (VRE) and clostridioides difficile in immunocompromised adults. Methods We performed a cluster randomized crossover control trial in 4 cancer and 1 solid organ transplant in-patient units at the Johns Hopkins Hospital, Baltimore, Maryland. For study year 1, each unit was randomized to intervention of UV-c light plus standard environmental cleaning or control of standard environmental cleaning, followed by a 5-week washout period. In study year 2, units switched assignments. The outcomes were healthcare-associated rates of VRE or c. difficile. Statistical inference used a two-stage approach recommended for cluster-randomized trials with Results In total, 302 new VRE infections were observed during 45787 at risk patient-days. The incidence in control and intervention groups was 6.68 and 6.52 per 1000 patient-days respectively;the unadjusted incidence rate ratio (IRR) was 0.98 (95% confidence interval [cI], .78 - 1.22;P = .54). There were 84 new c. difficile infections observed during 26118 at risk patient-days. The incidence in control and intervention periods was 2.64 and 3.78 per 1000 patient-days respectively;the unadjusted IRR was 1.43 (95% cI, .93 - 2.21;P = .98). conclusions When used daily and at post discharge in addition to standard environmental cleaning, UV-c disinfection did not reduce VRE or c. difficile infection rates in cancer and solid organ transplant units.
Pacificcod (Gadus macrocephalus), as one of the most important economic fish, was seriously infected by the nervous necrosis virus (NNV), especially in the larvae stage. PolyI:c is an effective stimulus of the antivi...
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Pacificcod (Gadus macrocephalus), as one of the most important economic fish, was seriously infected by the nervous necrosis virus (NNV), especially in the larvae stage. PolyI:c is an effective stimulus of the antivirus system, but whether it can work in the larvae stage is still unknown. In this study, the transcriptomic profiles of 10 day-post hatching (dph) cod larvae challenged with polyI:c was analysed using next-generation sequencing technology. After assembly and annotation, a total of 77,562 unigenes were acquired and 780 differentially expressed genes (DEGs) were identified, including 508 upregulated and 272 downregulated genes. The DEGs were involved in diverse pathways including protein processing in endoplasmic reticulum, peroxisome, carbon metabolism, fatty acid metabolism, and PPAR signaling pathway. Gene expression patterns of five immune relevant genes belonging to IFN signal pathway, such as TLR3, IRF3, MDA5, IPS1 and ATG5, were detected using qPcR. The transcript levels of TLR3, IRF3, MAD5 and IPS1 in cod larvae seems very low, but these genes were upregulated significantly 48h post-challenged with polyI:c, while ATG5 was downregulated 12h after polyI:cchallenged. The results indicated that IFN system of cod larvae can be induced by polyI:c, thus considering polyI:c as a potential antivirus agent for cod larvae.
Three new steroidal glycosides, metapregnoside A-c (II-IV), together with one known compound, byzantionoside B (I), were isolated from the fresh whole herb of Metaplexis japonica by using high-speed countercurrent chr...
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Three new steroidal glycosides, metapregnoside A-c (II-IV), together with one known compound, byzantionoside B (I), were isolated from the fresh whole herb of Metaplexis japonica by using high-speed countercurrent chromatography and semi-preparative liquid chromatography. Their structures and relative configurations were elucidated by spectroscopic methods including 1D NMR, 2D NMR and HR-ESI-MS. The potential targets of compound I-IV were identified by virtual screening. And the potential inhibitory effects of these compounds on tyrosine protein kinases were compared by molecular docking. Byzantionoside B (I) was the first isolated compound from Metaplexis genus. The docking score of metapregnoside c (IV) was the highest. And the sugar chain residues at position c-20 in the pregn-4-en-3-one derivatives is the main factor affecting their docking scores on tyrosine protein kinases Fes/Fps.
Fruit trees are perennial plant to have a characteristic requiring a long juvenile period until fruit set in general. Developing to release a new fruit cultivar is a laborious and cost- and time-consuming work. Especi...
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Fruit trees are perennial plant to have a characteristic requiring a long juvenile period until fruit set in general. Developing to release a new fruit cultivar is a laborious and cost- and time-consuming work. Especially, citrus breeding is not always feasible due to its cross-incompatible, sterile, and polyembryoniccharacteristics. Therefore, mutagenesis has been widely applied to citrus breeding to increase mutation frequency and genetic variability enabling development of new genotypes as an alternative method. Recently, various tangor (citrus unshiu x c. sinensis) cultivars were released through interspecific hybridization. Many attempts have been made to induce mutations in developing tangor cultivars, while their physiological effects have not been verified yet. To investigate the effect of gamma-irradiation exerted on tangor cultivar 'Kanpei', its scions were irradiated with 20, 40, 60, 80, and 100 Gy of gamma-rays. Then, we examined the SPAD values between the gamma-irradiated M-0 plants comparing with control 'Kanpei' (0 Gy). Interestingly, we found that there are variations in SPAD values among different treatments. This implies that mutation breeding should consider different factors other than the target traits.
The death of c. Richard conti, MD, MAcc in February 2022 marked the passing of a global leader in cardiology who played a pivotal role in the history of the American college of cardiology and the college's outreac...
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The death of c. Richard conti, MD, MAcc in February 2022 marked the passing of a global leader in cardiology who played a pivotal role in the history of the American college of cardiology and the college's outreach to the People's Republic of china.
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