Comprehensive Summary
The development of catalytic aerobic epoxidation by numerous metal complexes in the presence of aldehyde as a sacrificial reductant (Mukaiyama epoxidation) has been reported, ...however, comprehensive examination of oxygen atom transfer mechanism involving free radical and highly reactive intermediates has yet to be presented. Herein, meso‐tetrakis(pentafluorophenyl) porphyrinatooxidovanadium(IV) (VOTPFPP) was prepared and proved to be efficient toward aerobic olefin epoxidation in the presence of isobutyraldehyde. In situ electron paramagnetic resonance spectroscopy (in situ EPR) showed the generation, transfer pathways and ascription of free radicals in the epoxidation. According to the spectral and computational studies, the side‐on vanadium‐peroxo complexes are considered as the active intermediate species in the reaction process. In the cyclohexene epoxidation catalyzed by VOTPFPP, the kinetic isotope effect value of 1.0 was obtained, indicating that epoxidation occurred via oxygen atom transfer mechanism. The mechanism was further elucidated using isotopically labeled dioxygen experiments and density functional theory (DFT) calculations.
Oxo vanadium porphyrins are proved to be efficient for the aerobic epoxidation of olefins. The exact types of free radicals and their transfer pathways are characterized by operando EPR. VO(O) porphyrin π‐cation radical species from O—O bond homolysis of VO‐acylperoxo species was identified and characterized spectroscopically.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The ring‐opening alternating copolymerization (ROAC) of biorenewable glycidyl ethers with 3,4‐dihydrocoumarin (DHC) was achieved by using metal‐free Lewis pair as catalyst. This mild process provided ...access to renewable polyesters with perfectly alternating structures and functional groups fidelity. Remarkably, we observed highly regioregular arrangement of substituents along with poly(phenol ether‐alt‐ester) backbone. A one‐step strategy to block copolymer could also be realized by terpolymerization of DHC, epoxides with cyclic anhydrides via pre‐rate‐determining selectivity. Post‐polymerization modification of the resultant polyesters was further performed by thiol‐ene click reaction of vinyl, Diels–Alder reaction of furyl, cleavage reaction of benzyl ethers and tetrazine click reaction. By incorporating two different pendant functional groups into a copolymer, combinatorial and selective functionalization was achieved for introducing additional functionality, giving a route to highly modifiable polyesters. Therefore, this work provides a paradigm for designing functional and regioregular polyesters as a green synthetic toolbox derived from organocatalysis and renewable feedstocks.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This paper considers the random coefficient autoregressive model with time-functional variance noises, hereafter the RCA-TFV model. We first establish the consistency and asymptotic normality of the ...conditional least squares estimator for the constant coefficient. The semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed, and their asymptotic results are reported. A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The prevalence of childhood obesity has been increasing worldwide. The connection between iron deficiency and obesity has received much research interest. The present study examined the profiles of ...anemia among school-aged children categorized by obesity-related index in Shandong, China.
A total of 20,172 children aged 7, 9, 12, and 14 years participated in the study, whose hemoglobin (Hb) concentration was measured by laboratory technicians. The prevalence rates of anemia among children within each subgroup categorized by body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) were determined.
On the whole, 3.99% of boys and 6.68% of girls suffer from anemia. Disparities in the prevalence of anemia were observed between different subgroups categorized by BMI, WC and WHtR. For both boys and girls, the prevalence of anemia increased with the severity of thinness and obesity, suggesting that both severe thinness and severe obesity are associated with an elevated prevalence of anemia.
In the era of the obesity pandemic, obesity could potentially add to the burden of anemia, suggesting that obese children should not be ignored when establishing strategies targeted at preventing anemia.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
There is an urgent need to identify potential targets in anticancer therapy to improve the survival and prognosis of patients with ovarian cancer (OC). Herein, we investigated the functional ...significance of chemokine (C-X-C motif) ligand 14 (CXCL14) in OC cell growth and epithelial-mesenchymal transition (EMT).
qRT PCR and western blotting was used to detect CXCL14 mRNA level and protein expression, respectively. The functional mechanism of CXCL14 in OC was investigated by CCK-8, colony formation and transwell assays. The migration ability of OC cell was determined using wound healing. The protein expressions of CXCL14 and β-catenin in OC tissues were determined by immumohistochemical staining.
We demonstrated that high levels of CXCL14 were associated with a worse prognosis in patients with OC. CXCL14 knockdown considerably restrained the growth, migration and invasion of OC cell in vitro. In contrast, ectopic CXCL14 overexpression yielded the opposite results. Investigations to determine the underlying molecular mechanisms revealed that the Wnt/β-catenin signaling pathway is involved in CXCL14-facilitated OC cell invasiveness.
These data collectively demonstrate that CXCL14 contributes to OC cell growth and metastatic potential by regulating the Wnt/β-catenin signaling pathway.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Scope
To investigate the effects of postoperative parenteral nutrition (PN) with multivitamins supplementation on oxidative stress and metabolism.
Methods and results
The participants are randomly ...assigned in a 1:1 ratio to groups: total nutrient admixture (TNA) + multivitamin (n = 14, Group A) and TNA + normal saline (n = 16, Group B). The levels of blood vitamins, ILs, and MDA are assessed and the dysregulation of metabolism is analyzed using nontargeted metabolite profiling. The degree of postoperative stress in Group A is significantly lower than that in Group B by analyzing changes in the levels of IL‐8 and MDA. A set of 43 features are qualified to have a variable importance parameter score of >1.5 of a partial least‐squares discriminate analysis model and fold change of >1.5 at p‐value <0.05 between Groups A and B. The principal metabolic alternations in Group A include increased tricarboxylic acid cycle and ketogenesis with reduced plasma‐free amino acids. Backing the results of clinical biomarkers, increased levels of antioxidative molecules, together with decreased levels of inflammatory related polyunsaturated fatty acids, are observed.
Conclusion
Postoperative PN enhanced by multivitamins can alleviate traumatic stress and improve metabolic transition from catabolism to anabolism in gastric cancer patients.
The effects of postoperative multivitamin supplementation on stress damage and metabolism are examined by using nontargeted metabolite profiling in a RCT that enrolled gastric cancer patients receiving short‐term parenteral nutrition. The metabolic network analysis reveals differences in metabolites associated with energy metabolism (elevated glycolysis, ketogenesis, and tricarboxylic acid cycle), protein synthesis, and antioxidant defense (elevated antioxidative molecules with reduced inflammatory related polyunsaturated fatty acids).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
The geographic origin and migration of the brown rat (Rattus norvegicus) remain subjects of considerable debate. In this study, we sequenced whole genomes of 110 wild brown rats with a ...diverse world-wide representation. We reveal that brown rats migrated out of southern East Asia, rather than northern Asia as formerly suggested, into the Middle East and then to Europe and Africa, thousands of years ago. Comparison of genomes from different geographical populations reveals that many genes involved in the immune system experienced positive selection in the wild brown rat.
The choice of optimal reference gene is challenging owing to the varied expression of reference genes in different organs, development stages, and experimental treatments. Brandt's vole (
) is an ...ideal animal to explore the regulatory mechanism of seasonal breeding, and many studies on this vole involve gene expression analysis using quantitative real-time polymerase chain reaction (qRT-PCR). In this study, we used the method of the coefficient of variation and the NormFinder algorithm to evaluate the performance of nine commonly used reference genes
,
,
,
,
,
,
,
and
using qRT-PCR in eight different tissues, five developmental stages, and three different photoperiods. We found that all nine genes were not uniformly expressed among different tissues.
and
were the optimal reference genes for different postnatal development stages in the hypothalamus for males and females, respectively. Under different photoperiods in the hypothalamus, none of the selected genes were suitable as reference genes at 6 weeks postnatal;
and
were the optimal reference genes at 12 weeks postnatal;
,
,
,
, and
were excellent reference genes at 24 weeks postnatal. The present study provides a useful basis for selecting the appropriate reference gene in
.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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