Synthesis of 1-Benzyl-2,4-diarylimidazole through I2/CuI-Catalyzed Cyclization of Benzylamine and Hydrazone.

In this paper, we report an innovative method for synthesizing 1-benzyl-2,4-diarylimidazole utilizing 1-phenylethanone-2-(2-pyridinyl) hydrazine and benzylamine, catalyzed by an I2/CuI system. This approach represents a significant departure from traditional methods for synthesizing polysubstituted imidazoles; it employs the I2/CuI catalyst to replace rare metal catalysts, thereby achieving high yields of substitution products (≤85%). This method for the generation of 1,2,4-triimidazole derivatives is characterized by its exceptional chemical selectivity and extensive substrate compatibility.

Piston Sensing for Golay-6 Sparse Aperture System with Double-Defocused Sharpness Metrics via ResNet-34.

In pursuit of high imaging quality, optical sparse aperture systems must correct piston errors quickly within a small range. In this paper, we modified the existing deep-learning piston detection method for the Golay-6 array, by using a more powerful single convolutional neural network based on ResNet-34 for feature extraction; another fully connected layer was added, on the basis of this network, to obtain the best results. The Double-defocused Sharpness Metric (DSM) was selected first, as a feature vector to enhance the model performance; the average RMSE of the five sub-apertures for valid detection in our study was only 0.015λ (9 nm). This modified method has higher detecting precision, and requires fewer training datasets with less training time. Compared to the conventional approach, this technique is more suitable for the piston sensing of complex configurations.

Ultrasound-guided percutaneous microwave ablation for 755 benign breast lesions: a prospective multicenter study.

OBJECTIVES: To evaluate the clinical efficacy of microwave ablation (MWA) of benign breast lesions (BBLs) and compare the learning curves of international radiologists (IRs) and surgeons. METHODS: In total, 440 patients with 755 clinicopathologically confirmed BBLs from 5 centers were prospectively enrolled from February 2014 to July 2018. Technical success, complications, volume reduction ratio (VRR), palpability, and cosmetic satisfaction after ablation were analyzed. In addition, the ablation time (AT) and energy (AE) with the number of procedures were analyzed for learning curve evaluation. RESULTS: The mean maximum diameter was 1.7 ± 0.6 cm. The complete ablation rate reached 100%, including 45.8% lesions adjacent to the skin, pectoralis, or areola. After a median follow-up of 13.7 months, the 12-month VRR of all lesions was 97.9%, and that for 1.0- to 2.0-cm and ≥ 2.0-cm lesions was 98.6% and 96.9%, respectively. A total of 55.9% of BBLs became nonpalpable (palpable in 85.7% of cases before MWA) by both the clinician and patient. The cosmetic and minimally invasive satisfaction rates were good or excellent in 98.4% and 94.5% of patients, respectively. The median AT/cm3 and AE/cm3 decreased as experience increased. The AE/cm3 of the IR with 5 years of experience was lower than that of the IR with 1 year of experience and the surgeons, while the AT/cm3 of surgeons was comparable with that of the IR with 5 years of experience at relatively mature phase. CONCLUSIONS: Ultrasound-guided percutaneous MWA is a valuable technique for the treatment of BBLs. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02860104) KEY POINTS: • Ultrasound-guided percutaneous microwave ablation has the potential to become a valuable technique for the treatment of benign breast lesions. • A skilled interventional radiologist shows a rapid improvement in mastering the technique.

Transcriptome analysis reveals the temporal gene expression patterns in skin of large yellow croaker (Larimichthys crocea) in response to Cryptocaryon irritans infection.

Large yellow croaker (Larimichthys crocea) is one of the most important mariculture fish in China. In the past decades, cryptocaryonosis caused by Cryptocryon irritans has led to huge economic losses, posing great threat to the healthy and sustainable development of L. crocea mariculture industry. As the largest immunologically active mucosal organ in fish, skin provides the first defense line against external pathogens. To better understand the gene expression dynamics, the large yellow croakers were artificially infected with C. irritans and their skin tissues were collected at 0 h, 24 h, 48 h, 72 h and 96 h post infection. The total RNA in the skin tissues were extracted and the transcriptome were sequenced. After sequencing, a total of 1,131, 311, 140 million high quality RNA-seq reads were collected. A set of 215, 473, 968, 1055 differentially expressed genes were identified at 24 h, 48 h, 72 h and 96 h post infection respectively. Further analysis clustered these DEGs into six profiles and 75 hub genes for six profiles were identified. Among these hub genes, 18 immune related genes including TLR5, TOPK, NFKBIZ, MAPK14A were identified post C. irritans infection. Cytokine-cytokine receptor interaction was the only pathway that significantly enriched at four timepoints post infection. This study provides an in-depth understanding of skin transcriptome variance of large yellow croaker after C. irritans infection, which would be helpful for further understanding of the molecular mechanism of L. crocea in response to C. irritans infection.

Rhodium-catalyzed ortho-acrylation of aryl ketone O-methyl oximes with cyclopropenones.

An efficient Rh-catalyzed ortho-acrylation reaction for the synthesis of chalcones from O-methyl ketoximes and cyclopropenones via C-H bond activation has been described. This cross-coupling reaction exhibits high functional group tolerance and regioselectivity. A wide range of chalcone derivatives are obtained in moderate to good yields under mild conditions.

Transcriptional differences provide insight into environmental acclimatization in wild amur ide (Leuciscus waleckii) during spawning migration from alkalized lake to freshwater river.

Amur ide (Leuciscus waleckii) inhabits alkaline water in Lake Dali Nur and migrates to fresh water river for spawning every year. To investigate the potential genetic mechanisms underlying their alkaline acclimation, adaptation, and spawning migration, we performed differential gene expression analysis using high-throughput RNA-Seq data from liver of Amur ide samples collected before and after spawning migration. First, the short RNA-Seq reads were de novo assembled into 44,318 contigs, and provided the transcriptome reference sequences. Differential gene expression analysis identified 2575 genes with significant differential expression (p-value ≤.01, log2-fold-change ≥2). GO enrichment and KEGG pathway analyses were subsequently performed to determine gene functions and regulation. The results indicated that there were numerous differentially expressed genes involved in acid-base regulation, nitrogenous waste excretion, sexual maturation and reproduction, and stress response. These results provide fundamental information for further analyses of the physiological and molecular mechanisms underlying Amur ide alkaline acclimation, adaptation, and spawning migration.

Structure of the DNA-binding domain of human myelin-gene regulatory factor reveals its potential protein-DNA recognition mode.

Myelin-gene regulatory factor (MYRF) is a membrane-bound transcription factors, which is responsible for the differentiation of oligodendrocytes and myelination of central nervous system. Followed by a self-cleavage by the intramolecular chaperone auto-processing (ICA) domain, DNA-binding domain (DBD) of MYRF is released from the endoplasmic reticulum (ER) and was then translocated to the nucleus to regulate gene expression. In present work, we have solved the crystal structure of the human MYRF-DBD to 1.85-Å resolution. It exhibits a typical s-type Ig-fold and packs as symmetric trimeric form in the crystal via hydrogen-bond networks in three regions. Accordingly, we identified a couple of key residues on MYRF-DBD, which might play important roles in DNA-binding, in particular Arg521 on its C-terminal tail. The R521A mutant of DBD showed only 17% affinity to dsDNA targets compared to wild-type DBD. Then we built a plausible protein-DNA binding model of MYRF-DBD, which will help to elucidate its mechanism in DNA-binding and transcriptional regulation.

Genomic Basis of Adaptive Evolution: The Survival of Amur Ide (Leuciscus waleckii) in an Extremely Alkaline Environment.

The Amur ide (Leuciscus waleckii) is a cyprinid fish that is widely distributed in Northeast Asia. The Lake Dali Nur population inhabits one of the most extreme aquatic environments on Earth, with an alkalinity up to 50 mmol/L (pH 9.6), thus providing an exceptional model with which to characterize the mechanisms of genomic evolution underlying adaptation to extreme environments. Here, we developed the reference genome assembly for L. waleckii from Lake Dali Nur. Intriguingly, we identified unusual expanded long terminal repeats (LTRs) with higher nucleotide substitution rates than in many other teleosts, suggesting their more recent insertion into the L. waleckii genome. We also identified expansions in genes encoding egg coat proteins and natriuretic peptide receptors, possibly underlying the adaptation to extreme environmental stress. We further sequenced the genomes of 10 additional individuals from freshwater and 18 from Lake Dali Nur populations, and we detected a total of 7.6 million SNPs from both populations. In a genome scan and comparison of these two populations, we identified a set of genomic regions under selective sweeps that harbor genes involved in ion homoeostasis, acid-base regulation, unfolded protein response, reactive oxygen species elimination, and urea excretion. Our findings provide comprehensive insight into the genomic mechanisms of teleost fish that underlie their adaptation to extreme alkaline environments.

Metal-free iodine(iii)-promoted synthesis of 2,5-diaryloxazoles.

A nonmetal-catalyzed oxidative cyclization to achieve 2,5-disubstituted oxazoles from inexpensive and readily available substituted chalcone, (diacetoxyiodo)benzene (PIDA) and ammonium acetate (NH4OAc) at room temperature is described. The reaction forms a variety of 2,5-diaryloxazoles in good to excellent yields with broad substrate scope under mild conditions without the requirement of ligands and additional bases.

Synthesis of 2,3-Disubstituted NH Indoles via Rhodium(III)-Catalyzed C-H Activation of Arylnitrones and Coupling with Diazo Compounds.

A rhodium-catalyzed intermolecular coupling between arylnitrones and diazo compounds by C-H activation/[4 + 1] annulation with a C(N2)-C(acyl) bond cleavage is reported, and 2,3-disubstituted NH indoles are directly synthesized in up to a 94% yield. A variety of functional groups are applicable to this reaction to give the corresponding products with high selectivity. Compared to other previously reported Rh(III)-catalyzed synthesis of homologous series, this method is simpler, more general, and more efficient.

Copper-Catalyzed Tandem Aerobic Oxidative Cyclization for the Synthesis of Polysubstituted Quinolines via C(sp3)/C(sp2)-H Bond Functionalization.

One-pot Cu-catalyzed tandem aerobic oxidative cyclization for the synthesis of quinolines from 2-vinylanilines/2-arylanilines and 2-methylquinolines via C(sp3)-H/C(sp2)-H bond functionalization has been developed. Dioxygen as an ideal oxidant has been employed for this transformation. The substrates bearing various functional groups perform well in this process and generate the desired products in moderate to good yields.

OMS-2-Supported Cu Hydroxide-Catalyzed Benzoxazoles Synthesis from Catechols and Amines via Domino Oxidation Process at Room Temperature.

In the presence of manganese oxide octahedral molecular sieve (OMS-2) supported copper hydroxide Cu(OH)x/OMS-2, aerobic synthesis of benzoxazoles from catechols and amines via domino oxidation/cyclization at room temperature is achieved. This heterogeneous benzoxazoles synthesis initiated by the efficient oxidation of catechols over Cu(OH)x/OMS-2 tolerates a variety of substrates, especially amines containing sensitive groups (hydroxyl, cyano, amino, vinyl, ethynyl, ester, and even acetyl groups) and heterocycles, which affords functionalized benzoxazoles in good to excellent yields by employing low catalyst loading (2 mol % Cu). The characterization and plausible catalytic mechanism of Cu(OH)x/OMS-2 are described. The notable features of our catalytic protocol such as the use of air as the benign oxidant and EtOH as the solvent, mild conditions, ease of product separation, being scalable up to the gram level, and superior reusability of catalyst (up to 10 cycles) make it more practical and environmentally friendly for organic synthesis.

Cramér-Rao lower bound analysis of phase diversity for sparse aperture optical systems.

Aberration detection of subapertures is critical to the resolution of a sparse aperture optical system. In this work, the Cramér-Rao lower bound (CRLB) expression of aberrations was first derived for the subapertures of a sparse aperture optical system. The aberrations were estimated by phase diversity, assuming that the photons follow the Poisson distribution. The derived formula has been applied to the Golay3 sparse aperture system to calculate the CRLB of the subapertures' aberrations with different defocus distances, fill factors, and ratios of photon numbers between the focal and defocal images. According to the CRLB criterion, the results indicate that the accuracy of aberration estimation increases as the fill factor of the sparse aperture system increases. The results also demonstrate that the optimal defocus distance of phase diversity is achieved when the CRLB reaches its minimum. The optimal ratio of photon numbers between the focal and defocal images is around 3∶7. However, for the piston error, more photons in the defocal image yield more accurate estimation results. This method can also be applied to the sparse aperture optical systems with other different configurations.

Synthesis of Polyfunctional Pyridines via Copper-Catalyzed Oxidative Coupling Reactions.

An efficient and concise approach for the synthesis of polysubstituted pyridines has been achieved through copper-catalyzed oxidative sp3 C-H coupling of oxime acetates with toluene derivatives. Besides, benzylamine and p-toluenesulfonylhydrazone were also introduced to react with oxime acetates to enrich the diversity of this synthetic method. These transformations provide highly flexible and facile preparation of substituted pyridines and thus are useful in practical synthesis.

Synthesis, Characterization and Antifungal Evaluation of Novel Thiochromanone Derivatives Containing Indole Skeleton.

Invasive fungal disease constitutes a growing health problem and development of novel antifungal drugs with high potency and selectivity against new fungal molecular targets are urgently needed. In order to develop potent antifungal agents, a novel series of 6-alkyl-indolo[3,2-c]-2H-thiochroman derivatives were synthesized. Microdilution broth method was used to investigate antifungal activity of these compounds. Most of them showed good antifungal activity in vitro. Compound 4o showed the best antifungal activity, which (inhibition of Candida albicans and Cryptococcus neoformans) can be achieved at the concentration of 4 µg/mL. Compounds 4b (inhibition of Cryptococcus neoformans), 4j (inhibition of Cryptococcus neoformans), 4d (inhibition of Candida albicans) and 4h (inhibition of Candida albicans) also showed the best antifungal activity at the concentrations of 4 µg/mL. The molecular interactions between 4o and the N-myristoyltransferase of Candida albicans (PDB ID: 1IYL) were finally investigated through molecular docking. The results indicated that these thiochromanone derivatives containing indole skeleton could serve as promising leads for further optimization as novel antifungal agents.

[Studies on chemical constituents of Valeriana plants and their biological activities].

The recent progresses on chemical components and pharmacological activities of the genus Valerianawere summarized.Besides-essential oil, the chemical composition of Valerianais mainly focused on monoterpenoids,sesquiterpenoids,lignans, flavonoids, alkaloids, etc. Iridoids are the main chemical components ofmonoterpenoids. There are two types ofiridoidson the basis of the cyclopentane open or not. The Valerianahas been drawmuch attention for their significant sedation,spasmolysis,antidepression,antitumor, against adenosine A1 receptors and cytotoxicityactivity,and had certain function for cardiovascular disease treatment. Given to the fact of the lack of systematic review and summary of studies on the Valeriana, we summarized and analyze the study literatures on the pharmacological activity of Valerianain recent years, and providedsome basisfor further study.

Evolutionary divergence of subgenomes in common carp provides insights into speciation and allopolyploid success.

Hybridization and polyploidization have made great contributions to speciation, heterosis, and agricultural production within plants, but there is still limited understanding and utilization in animals. Subgenome structure and expression reorganization and cooperation post hybridization and polyploidization are essential for speciation and allopolyploid success. However, the mechanisms have not yet been comprehensively assessed in animals. Here, we produced a high-fidelity reference genome sequence for common carp, a typical allotetraploid fish species cultured worldwide. This genome enabled in-depth analysis of the evolution of subgenome architecture and expression responses. Most genes were expressed with subgenome biases, with a trend of transition from the expression of subgenome A during the early stages to that of subgenome B during the late stages of embryonic development. While subgenome A evolved more rapidly, subgenome B contributed to a greater level of expression during development and under stressful conditions. Stable dominant patterns for homoeologous gene pairs both during development and under thermal stress suggest a potential fixed heterosis in the allotetraploid genome. Preferentially expressing either copy of a homoeologous gene at higher levels to confer development and response to stress indicates the dominant effect of heterosis. The plasticity of subgenomes and their shifting of dominant expression during early development, and in response to stressful conditions, provide novel insights into the molecular basis of the successful speciation, evolution, and heterosis of the allotetraploid common carp.

Synthesis of multisubstituted imidazoles via copper-catalyzed [3 + 2] cycloadditions.

A simple route for the synthesis of imidazole derivatives via copper-catalyzed [3 + 2] cycloaddition reaction is described. This strategy has achieved high regioselectivity and used oxygen as an oxidant without the addition of expensive catalysts to provide moderate to good yields.

Comparative genomics analysis and genome assembly integration with the recombination landscape contribute to Takifugu bimaculatus assembly refinement.

Takifugu genus has been brought to the fore in scientific and practical research due to its compact genome, explosive speciation progress and economic value. Here we updated the chromosome-level genome of Takifugu bimaculatus by an ultra-high-density linkage map, a classic and accurate way of chromosome assembly. The map constituted a robust assembly frame, with 92.2% (372.77 Mb) of the draft genome cumulatively placed. With intraspecies and interspecies comparative genomic analysis, we developed a criterion to quantify the differences between assemblies and established a novel way to integrate information from multiple assemblies. The integrated assembly rectified potential mis-assemblies, greatly improving the genome contiguity and correctness. Our results rendered profound information on the genetic recombination of T. bimaculatus and provided new insights into effective genome assembly. The consolidated assembly will be a contributory tool of T. bimaculatus and broadly across the Takifugu by providing a convincing reference for genomic research.

Population structure and genome-wide evolutionary signatures reveal putative climate-driven habitat change and local adaptation in the large yellow croaker.

The large yellow croaker (Larimichthys crocea) is one of the most economically valuable marine fish in China and is a notable species in ecological studies owing to a serious collapse of wild germplasm in the past few decades. The stock division and species distribution, which have important implications for ecological protection, germplasm recovery, and fishery resource management, have been debated since the 1960s. However, it is still uncertain even how many stocks exist in this species. To address this, we evaluated the fine-scale genetic structure of large yellow croaker populations distributed along the eastern and southern Chinese coastline based on 7.64 million SNP markers. Compared with the widely accepted stock boundaries proposed in the 1960s, our results revealed that a climate-driven habitat change probably occurred between the Naozhou (Nanhai) Stock and the Ming-Yuedong (Mindong) Stock. The boundary between these two stocks might have shifted northwards from the Pearl River Estuary to the northern area of the Taiwan Strait, accompanied by highly asymmetric introgression. In addition, we found divergent landscapes of natural selection between the stocks inhabiting northern and southern areas. The northern population exhibited highly agminated signatures of strong natural selection in genes related to developmental processes, whereas moderate and interspersed selective signatures were detected in many immune-related genes in the southern populations. These findings establish the stock status and genome-wide evolutionary landscapes of large yellow croaker, providing a basis for conservation, fisheries management and further evolutionary biology studies. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00165-2.