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SUMMARY: Erianin, crepidatin, and chrysotobibenzyl are typical medicinal polymethoxylated bibenzyls (PMBs) that are commercially produced in Dendrobium species. PMBs' chemo‐diversity is mediated by the manifold combinations of O‐methylation and hydroxylation in a definite order, which remains unsolved. To unequivocally elucidate the methylation mechanism of PMBs, 15 possible intermediates in the biosynthetic pathway of PMBs were chemically synthesized. DcOMT1–5 were highly expressed in tissues where PMBs were biosynthesized, and their expression patterns were well‐correlated with the accumulation profiles of PMBs. Moreover, cell‐free orthogonal tests based on the synthesized intermediates further confirmed that DcOMT1‐5 exhibited distinct substrate preferences and displayed hydroxyl‐group regiospecificity during the sequential methylation process. The stepwise methylation of PMBs was discovered from SAM to dihydro‐piceatannol (P) in the following order: P → 3‐MeP → 4‐OH‐3‐MeP → 4‐OH‐3,5‐diMeP → 3,3'(4′),5‐triMeP → 3,4,4′,5‐tetraMeP (erianin) or 3,3′,4,5‐tetraMeP (crepidatin) → 3,3′,4,4′,5‐pentaMeP (chrysotobibenzyl). Furthermore, the regioselectivities of DcOMTs were investigated by ligand docking analyses which corresponded precisely with the catalytic activities. In summary, the findings shed light on the sequential catalytic mechanisms of PMB biosynthesis and provide a comprehensive PMB biosynthetic network in D. catenatum. The knowledge gained from this study may also contribute to the development of plant‐based medicinal applications and the production of high‐value PMBs. [ABSTRACT FROM AUTHOR]

Summary: Soybean is a short‐day plant that typically flowers earlier when exposed to short‐day conditions. However, the identification of genes associated with earlier flowering time but without a yield penalty is rare. In this study, we conducted genome‐wide association studies (GWAS) using two re‐sequencing datasets that included 113 wild soybeans (G. soja) and 1192 cultivated soybeans (G. max), respectively, and simultaneously identified a candidate flowering gene, qFT13‐3, which encodes a protein homologous to the pseudo‐response regulator (PRR) transcription factor. We identified four major haplotypes of qFT13‐3 in the natural population, with haplotype H4 (qFT13‐3H4) being lost during domestication, while qFT13‐3H1 underwent natural and artificial selection, increasing in proportion from 4.5% in G. soja to 43.8% in landrace and to 81.9% in improve cultivars. Notably, most cultivars harbouring qFT13‐3H1 were located in high‐latitude regions. Knockout of qFT13‐3 accelerated flowering and maturity time under long‐day conditions, indicating that qFT13‐3 functions as a flowering inhibitor. Our results also showed that qFT13‐3 directly downregulates the expression of GmELF3b‐2 which is a component of the circadian clock evening complex. Field trials revealed that the qft13‐3 mutants shorten the maturity period by 11 days without a concomitant penalty on yield. Collectively, qFT13‐3 can be utilized for the breeding of high‐yield cultivars with a short maturity time suitable for high latitudes. [ABSTRACT FROM AUTHOR]

Cancer stem cell (CSC) refers to cancer cells with stem cell properties, that is, they have the ability of "self-renewal" and "differentiation." Cancer stem cells exist in cancer cells and are the "culprit" of cancer recurrence and metastasis. It is difficult to be found because of its small amount, and it is difficult for anticancer drugs to produce effects on it. At present, the isolation and identification of cancer stem cells from many solid tumors are still quite difficult, mainly due to the lack of specific molecular markers of cancer stem cells. In this review, cancer stem cell surface markers and functional markers in urinary system were summarized. These markers can provide molecular targets for cancer therapy. [ABSTRACT FROM AUTHOR]

Innovations in genomics have enabled the development of low‐cost, high‐resolution, single nucleotide polymorphism (SNP) genotyping arrays that accelerate breeding progress and support basic research in crop science. Here, we developed and validated the SoySNP618K array (618,888 SNPs) for the important crop soybean. The SNPs were selected from whole‐genome resequencing data containing 2,214 diverse soybean accessions; 29.34% of the SNPs mapped to genic regions representing 86.85% of the 56,044 annotated high‐confidence genes. Identity‐by‐state analyses of 318 soybeans revealed 17 redundant accessions, highlighting the potential of the SoySNP618K array in supporting gene bank management. The patterns of population stratification and genomic regions enriched through domestication were highly consistent with previous findings based on resequencing data, suggesting that the ascertainment bias in the SoySNP618K array was largely compensated for. Genome‐wide association mapping in combination with reported quantitative trait loci enabled fine‐mapping of genes known to influence flowering time, E2 and GmPRR3b, and of a new candidate gene, GmVIP5. Moreover, genomic prediction of flowering and maturity time in 502 recombinant inbred lines was highly accurate (>0.65). Thus, the SoySNP618K array is a valuable genomic tool that can be used to address many questions in applied breeding, germplasm management, and basic crop research. [ABSTRACT FROM AUTHOR]

An enantioselective synthetic approach for preparing manginoids and guignardones, two types of biogenetically related meroterpenoids, is reported. This bioinspired and divergent synthesis employs an oxidative 1,3‐dicarbonyl radical‐initiated cyclization and cyclodehydration of the common precursor to forge the central ring of the manginoids and guignardones, respectively, at a late stage. Key synthetic steps include silica‐gel‐promoted semipinacol rearrangement to form the 6‐oxabicyclo[3.2.1]octane skeleton and the Suzuki–Miyaura reaction of vinyl bromide to achieve fragment coupling. This synthesis protocol enables the asymmetric syntheses of four fungal meroterpenoids from commercially available materials. [ABSTRACT FROM AUTHOR]

A divergent synthetic approach to biogenetically related diterpenoids such as ent‐kauranes, ent‐trachylobanes, ent‐beyerane, and ent‐atisane has been developed. The unified synthetic route involves the De Mayo reaction to rapidly generate the bicyclo[3.2.1]‐octane moiety of ent‐kaurane. The key reactions also include bioinspired nucleophilic cyclopropanation generating the [3.2.1.02,7]‐tricyclic core of ent‐trachylobane and regioselective cyclopropane fragmentation furnishing ent‐beyerane and ent‐atisane through the nucleophilic attack and protonation of the cyclopropane ring. This strategy enables the asymmetric total syntheses of six diterpenoids from the commercially available geraniol. [ABSTRACT FROM AUTHOR]

Effects of alloying Nb with Mo on the structure and hydrogen permeation properties of Nb metal have been investigated by XRD analysis, PCT measurements, and three-point bending tests. The results indicate that all the as-prepared Nb 100-x Mo x (x = 2, 7, 14) alloy samples are Nb-based solid solutions with a BCC structure, which are hydrogenated into their corresponding hydrides with the NbH 0.95 phase after interaction with hydrogen. The lattice deformations of the BCC structure and NbH 0.95 phase are due to the difference in size between Nb and Mo atoms. The Nb 86 Mo 14 sample has a higher hydrogen-diffusion coefficient value (1.84 × 10 −9 cm/s), higher hydride-formation enthalpies (- 35.8 kJ/(mol·H 2 )) with the maximum force and displacement before/after the hydrotreatment, indicating that alloying with Mo can greatly improve the hydrogen-diffusion behavior and anti-bending properties of Nb metal. [ABSTRACT FROM AUTHOR]

In order to assess the genetic diversity of peanut in Jiangsu Province, 133 accessions of peanut landraces were evaluated by 25 SSR markers. 93 alleles were amplified, and the average number of alleles per locus was 3.72. The polymorphic information content (PIC) of each primer varied from 0.066 to 0.749 with an average of 0.374. Shannon's information index of each primer varied from 0.161 to 1.385 with an average of 0.671. The similarity coefficients of 133 peanut landraces varied from 0.416 to 1.000 with an average of 0.830. The order of average similarity coefficient of 4 types of peanut was Arachis hypogaea L. var. hypogaea (0.899) > var. hirsute (0.776) > var. vulgaris (0.710) > var. fastigiata (0.700). Cluster analysis with UPGMA showed that the landraces could be divided into three groups at 0.600 of genetic similarities coefficient. The results showed that there were rich genetic diversity of peanut landraces in Jiangsu Province, and the genetic diversity was significantly lower among the var. hypogaea than those of the other three types. The result of cluster analysis had important significance for efficiently using of these peanut landraces. [ABSTRACT FROM AUTHOR]

Two monocyclic members in the gracilioether family were synthesized in only three steps. The monocyclic products were further elaborated into advanced precursors to hippolachnin A and gracilioether E, respectively. Gracilioether F and the alleged structure for gracilioether I were also synthesized using a late-stage C(sp3)-H thermo-oxidation. [ABSTRACT FROM AUTHOR]

The causes for the title reaction to be limited to only the alkenes with an unsubstituted terminal alkenic carbon were explored. In some 'failed' cases the cycloaddition products actually formed but rearranged concurrently. An oxygen atom or a N-Boc (Boc= tert-butyloxycarbonyl) group at the double bond was proven essential for acquisition of intact [3+2] cycloaddition products from 1,2-disubstituted ethylenes. [ABSTRACT FROM AUTHOR]

The long-known furanoterpenes furospongin-1 and dihydrofurospongin-2 were synthesized for the first time using a chiral-pool-based route in an effort to secure the previous configurational assignments. The key C-11 stereogenic centre was taken from D-mannose, and the C-13 alkyl centre was installed exploiting the chirality of mannose. Due to deprotonation and/or enolization of the building blocks used, introduction of the furan moieties was problematic, and so some reactions had to be avoided. The trisubstituted alkene was most satisfactorily constructed using a Julia-Kocienski olefination in 1,2-dimethoxyethane, with the best ( E)/( Z) ratio achieved using a secondary sulfone. The synthetic samples not only provided the first unequivocal piece of evidence for the C-13 configuration of both natural products, but also confirmed the absolute configuration at C-11 of furospongin-1. [ABSTRACT FROM AUTHOR]

Aim Background Methods Results Conclusion To evaluate the mediating roles of occupational resilience and the moderationg role of perceived organizational support in the relationship between career calling and nurse burnout.Burnout is a frequent and serious problem in the field of nursing, and it poses a serious threat to both nurses’ health and patient safety. Although many studies have described the links between burnout, career calling, and occupational resilience, little is known about the actual mechanisms between career calling and nurse burnout.A cross‐sectional study of 615 nurses in China was conducted using a convenience sampling method. The data were analyzed using descriptive statistics and Pearson correlation analysis. Hypotheses were tested using structural equation models and bootstrapping methods. STROBE guidelines were followed.Career calling was found to be negatively associated with nurse burnout, and occupational resilience mediated the relationship between career calling and burnout. Additionally, perceived organizational support was found to play a moderating role in the relationship between occupational resilience and burnout.Career calling can reduce burnout by increasing nurses' levels of occupational resilience, and perceived organizational support moderates this mechanism. Hence, policies focused on encouraging and sustaining career calling should be provided by nurse managers in order to enhance stress resistance and reduce burnout. [ABSTRACT FROM AUTHOR]

A graphical abstract of the study "Synthesis and Configurations of YF-0200R A and B" by X.-D. Wang and colleagues is presented.

The furanoterpenes, furospongin-1 (I) and dihydrofurospongin-2 (II), are prepared for the first time using a chiral-pool-based sequence. [ABSTRACT FROM AUTHOR]

The previously proposed structure containing a six-membered peroxide is proven to be misinterpretation of the MS data due to unawareness of a facile air oxidation. [ABSTRACT FROM AUTHOR]

• Children carrying CYP3A5*3 with higher body weight had a higher C 0 /Dose. • Routine CYP3A5 genotyping test played a minor role in <6-year-old pediatric patients. • Exposure levels (C 0 , 2–7 ng/mL) was sufficient to maintain remission status in children with RNS. Tacrolimus, an immunosuppressive drug, was recommended by the 2012 KDIGO guidelines to treat nephrotic syndrome (NS) in children and adults. However, it has high interpatient pharmacokinetic variability and exposure levels should be monitored, although there are no specified target concentrations. This retrospective study aimed to review efficacy and safety after concomitant treatment with tacrolimus and prednisone, and to identify factors that contribute to the variable blood-trough-concentration-to-dose (C 0 /Dose) ratio in children with refractory NS (RNS). A 6-month therapy induced complete or partial remission in 95% of patients. One-year follow-up indicated a high remission rate and low nephrotoxicity. Under maintenance dosages, approximately 95% of the C 0 values were 2–7 ng/mL. Body weight (BW), age, CYP3A5 polymorphisms were the factors affecting the C 0 /Dose ratio. The C 0 /Dose ratio in patients with a BW of <20 kg was 1.5-fold than that in patients with BW of ≥40 kg. Moreover, the C 0 /Dose ratio in patients aged 1–≤6 and 6–≤12 years was significantly lower than that in patients aged 12–≤18 years, by 25% and 48%, respectively. There were no significant association between CYP3A5 genotyping and C 0 /Dose ratio in younger children (1–≤6 years), rather than older children (6–≤18 years). In conclusion, routine CYP3A5 genotyping should be considered in children aged over 6 years and exposure levels (C 0) of 2–7 ng/mL may be feasible when tacrolimus is combined with low-dose prednisone to treat childhood RNS. [ABSTRACT FROM AUTHOR]