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A novel, practical, and scalable approach for the synthesis of eldecalcitol (2), via the Horner–Wadsworth–Emmons (HWE) olefination of A-ring and C/D-ring fragments, has been described. The improved route was carried out to produce the key intermediate chiral epoxide 17in good yield (13 steps, 9.0% overall yield) and high optical purity based on the utilization of d-mannose as a readily accessible, economically attractive chiral raw material. This process employed d-mannose as the chiral pool to directly assemble all the stereocenters of the A-ring fragment, thereby reducing the complexity of the chiral separation process, eliminating the need for asymmetric oxidation required for the construction of the C-3 stereocenter, and ultimately increasing the efficiency.

Oplopanax elatusNakai is an endangered perennial shrub of the Araliaceae family with various bioactive compounds, but its practical application is limited by the shortage of plant resource. Adventitious root (AR) culture is a novel approach for obtaining plant materials; thus, this study used the extract from bioreactor cultured O. elatusARs (OAE) as experimental material and investigated the effect of OAE on inhibiting melanin synthesis of mouse melanoma cells (B16-F10) to utilize the ARs in production of related products in the future. The results showed that tyrosinase activity and melanin content of B16-F10 cells were inhibited by the treatments of 12.5, 25, and 50 μg/mL OAE, but those did not significantly decrease at 6.25 μg/mL OAE, indicating the anti-melanin effect of OAE (≥12.5 μg/mL). OAE down-regulated the expressions of microphthalmia-associated transcription factor, tyrosinase, and tyrosinase-related proteins-I or -II. Furthermore, phosphorylation of cyclic adenosine monophosphate (cAMP) response element-binding protein was inhibited by OAE. Meanwhile, phosphorylation of mitogen-activated protein kinases (MAPKs) of p38 and c-Jun N-terminal kinase was also inhibited by OAE, whereas that of extracellular regulated protein kinases was promoted. These findings demonstrated that the anti-melanin effect of OAE is probably caused by the regulation of the cAMP and MAPK signaling pathways. In conclusion, O. elatusARs possess good anti-melanin effect and could be used in production of whitening products.

Anoectochilus roxburghii(Wall.) Lindl. is a precious herb plant and its rhizome cultures can be used as an alternative plant material. To utilize rhizomes in practical production, this study investigated the antibacterial and anti-biofilm effects of the rhizome extract (RhE) from (A) roxburghii, and further clarified the antibacterial mechanism. Results showed that RhE inhibited the growth of all tested bacterial species (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis) and the highest inhibitory zone (18.6 mm) was found on (B) subtilis, which was 4.8 mm more than the extract (PE) from the field-grown plants of (A) roxburghii. The RhE treatment increased the leakage of the alkaline phosphatase, electrolyte, nucleic acid, and protein of (B) subtilis, indicating that the cell permeability was increased. Furthermore, RhE inhibited the respiration of B. subtilisand decreased the activity eof the key enzyme (glucose-6-phosphate dehydrogenase) in the hexose monophosphate (HMP) pathway, proving that RhE was involved in the HMP pathway. In addition, RhE inhibited bacterial biofilm formation, which was higher than PE; Among the four tested bacteria, RhE treatment had strong inhibitory effect on biofilm formation of P. aeruginosaand B. subtilis. The findings suggested that A. roxburghiirhizome cultures are the potential material in the production of antibacterial and anti-biofilm products.

Artificial intelligence assistance improved radiologists’ performance in distinguishing coronavirus disease 2019 from pneumonia of other origin at chest CT.

Radiologists had high specificity but moderate sensitivity in differentiating coronavirus disease 2019 (COVID-19) from non-COVID-19 viral pneumonia at chest CT.

The evergreen broadleaved forests (EBLFs) of Southwest China have a long-term stable environment and support a diverse flora, thus forming a global biodiversity hotspot. However, the key drivers that have shaped the genetic diversity patterns of species in these EBLFs are not well understood. Quercus delavayi, Q. schottkyana, and Q. kerriiare sympatric oak species with different seed biological traits that are typical for these EBLFs. This study combined multilocus phylogeography and ecological niche modeling to screen 33 Q. delavayipopulations. Their population genetic structure was inferred in comparison with previous studies on Q. schottkyanaand Q. kerrii. The seed germination traits of all three species were also investigated. cpDNAs showed a significant phylogeographic structure in Q. delavayi, which was not detected in Q. schottkyanaor Q. kerrii. Quercus delavayi, Q. kerrii, and Q. schottkyanaexhibited different pollen-to-seed migration ratios (r= 219, 117, and 22, respectively), which are linked to the germination schedules of acorns. The distributions of Q. delavayiand Q. schottkyanaremained long-term stable since the last glacial maximum (LGM) with a similar nSSR genetic gradient change along latitude. Instead, Q. kerriiexperienced a prominent range expansion since the LGM with genetic diversification between the East and the West of the Tanaka line due to environmental heterogeneity. These results identify seed traits and environmental heterogeneity as two key drivers that shape the population genetic structure of EBLF trees in Southwest China. These should be considered in regional forestry conservation and management.

The retinoic acid receptor-related orphan receptor γt (RORγt) is a key regulator of Th17 cells, associated with autoimmune diseases, making it a significant drug target. Herein, we designed and synthesized 1-(phenylsulfonyl)-1,2,3,4-tetrahydroquinoline derivatives, improving upon GSK2981278 to enhance bioavailability. Of which, D4exhibited superior bioavailability (F = 48.1 and 32.9% in mice and rats, respectively) compared to GSK2981278 (F = 6.2 and 4.1%, respectively), and effectively treated psoriasis in mice at lower doses. Moreover, for the first time, we report the efficacies of a RORγt inverse agonist in mouse models of rheumatoid arthritis. (R)-D4, the eutomer of D4, matched or exceeded GSK2981278’s therapeutic effects at lower doses, with no adverse effects observed after 2 weeks of administration. These results position (R)-D4as a promising and orally bioavailable candidate for Th17-mediated autoimmune disease treatment.

Mammalian gametes and embryos are particularly vulnerable to oxidative stress-induced damage, which is mainly caused by reactive oxygen species (ROS) originating from normal metabolism and/or the external environment. Several researchers have implicated the role of oxidative stress in the activation of apoptosis, causing peroxidative damage to sperms/oocytes and inducing embryo fragmentation, arrest, or demise. Melatonin is a tryptophan derivative that is known for its powerful free radical-scavenging activity and broad-spectrum antioxidant property. Numerous studies have shown that melatonin and its metabolic derivatives can sequentially detoxify ROS in an antioxidant cascade, and modulate various antioxidant enzymes viaits receptors to prevent radical-mediated damage. The identification of melatonin receptors in cumulus/granulosa cells, oocytes, and epididymal tissues implies that melatonin has protective actions on gametes and embryos. Enriching the semen extender or culture medium with melatonin significantly benefits sperm characteristics, improves oocyte maturation potential and quality, and enhances the developmental competence of preimplantation embryos. Certainly, further comparative studies are needed to show the unique antioxidant role and the advantage of melatonin in this field. This review summarizes the harmful effects of ROS and the beneficial role of melatonin against oxidative damage of gametes and embryos.

Southwest China is one of the major global biodiversity hotspots. The Tanaka line, extending within southwestern China from its northwest to its southeast, is an important biogeographical boundary between the Sino-Japanese and Sino-Himalayan floristic regions. Understanding the evolutionary history of the regional keystone species would assist with both reconstructing historical vegetation dynamics and ongoing biodiversity management. In this research, we combined phylogeographic methodologies and species distribution models (SDMs) to investigate the spatial genetic patterns and distribution dynamics of Quercus kerrii, a dominant evergreen oak inhabiting southwest China lowland evergreen-broadleaved forests (EBLFs). A total of 403 individuals were sampled from 44 populations throughout southwest China. SDMs and mismatch distribution analysis indicated that Q. kerriihas undergone northward expansion since the Last Glacial Maximum (LGM). Quantitative analysis revealed that the range expansion of Q. kerriisince the LGM exceeded that of the sympatric mid-elevation species Quercus schottkyana, likely owing to their contrasting distribution elevations and habitat availabilities. The historical climate change since the LGM and the latitude gradient of the region played an important role in shaping the genetic diversity of Q. kerrii. The genetic differentiation index and genetic distance surface of Q. kerriipopulations east of the Tanaka line exceeded those to its west. The long-term geographic isolation and environmental heterogeneity between the two sides of the Tanaka line might increase species divergence patterns and local adaptation. This study provides new insights into the historical dynamics of subtropical EBLFs and the changing biota of southwest China.

h-PAMAM-COOMe and its β-CD derivatives (h-PAMAM-CD) were synthesized step by step via the Michael addition and ester-aminolysis reaction from hyperbranched polyamidoamine (h-PAMAM). The structures of the as-prepared polymers were confirmed by Ubbelohde viscometer, FTIR, and 1H NMR. A series of inclusion complexation formed by β-naphtol in increasing h-PAMAM-β-CD with different concerntration were investigated by UV-vis spectrometer. The result showed that the novel hyperbranched polymer might have potential applications as delivery materials in chemotherapy.

A series of nanocrystalline FeNbB films were fabricated using ion-beam sputtering technique from FeNbB target. Pieces of these films were annealed for 1 hour at various temperatures up to 5730C. Room temperature soft magnetic properties of these films were measured. The influence of microstructure on magnetic behavior in nanocrystalline FeNbB films is investigated in a series of specimens with different film’s thickness. For the sample 120nm and 5000C annealed, cutoff frequency was found to be 5E7 Hz, which has the μf0=5E10.

Functionally graded material (FGM) is well-known as one of the most promising materials in the 21st century, which has become the hot issue on its mechanical behavior and composition design. The optimization design of the material distribution properties for an FGM hollow vessel subjected to internal pressure were investigated in this paper. By constructing an exponentially function determining the material properties, the general analytical solution of the stresses of the FGM pressure vessel was given based on the Euler-Cauchy formula. And then, an optimization model for obtaining the optimal material distribution of FGM vessel was proposed coupling the general finite element (FE) code. The discrepancy between the analytical solution and the numerical solution was about 2%, which verified the reliability of the proposed models, and the optimization results also proved the feasibility of proposed optimization scheme because of arriving at the optimal solution in a few iterations. Results obtained would be helpful in designing an FGM pressure vessel.