A Very Deep Graph Convolutional Network for 13C NMR Chemical Shift Calculations with Density Functional Theory Level Performance for Structure Assignment.

Nuclear magnetic resonance (NMR) chemical shift calculations are powerful tools for structure elucidation and have been extensively employed in both natural product and synthetic chemistry. However, density functional theory (DFT) NMR chemical shift calculations are usually time-consuming, while fast data-driven methods often lack reliability, making it challenging to apply them to computationally intensive tasks with a high requirement on quality. Herein, we have constructed a 54-layer-deep graph convolutional network for 13C NMR chemical shift calculations, which achieved high accuracy with low time-cost and performed competitively with DFT NMR chemical shift calculations on structure assignment benchmarks. Our model utilizes a semiempirical method, GFN2-xTB, and is compatible with a broad variety of organic systems, including those composed of hundreds of atoms or elements ranging from H to Rn. We used this model to resolve the controversial J/K ring junction problem of maitotoxin, which is the largest whole molecule assigned by NMR calculations to date. This model has been developed into user-friendly software, providing a useful tool for routine rapid structure validation and assignation as well as a new approach to elucidate the large structures that were previously unsuitable for NMR calculations.

Sesquiterpenes and α-pyrones from an endophytic fungus Xylaria curta YSJ-5.

Chemical investigation of the culture extract of an endophyte Xylaria curta YSJ-5 from Alpinia zerumbet (Pers.) Burtt. et Smith resulted in the isolation of eight previously undescribed compounds including five eremophilane sesquiterpenes xylarcurenes A-E, one norsesquiterpene xylarcurene F, and two α-pyrone derivatives xylarpyrones A-B together with eight known related derivatives. Their chemical structures were extensively established based on the 1D- and 2D-NMR spectroscopic analysis, modified Mosher's method, electronic circular dichroism calculations, single-crystal X-ray diffraction experiments, and the comparison with previous literature data. All these compounds were tested for in vitro cytotoxic, anti-inflammatory, α-glucosidase inhibitory, and antibacterial activities. As a result, 6-pentyl-4-methoxy-pyran-2-one was disclosed to display significant antibacterial activity against Staphylococcus aureus and methicillin-resistant S. aureus with minimal inhibitory concentration value of 6.3 µg/mL.

Chemical Constituents and Bioactivities of the Plant-Derived Fungus Aspergillus fumigatus.

A new bergamotane sesquiterpenoid, named xylariterpenoid H (1), along with fourteen known compounds (2-15), were isolated from the crude extract of Aspergillus fumigatus, an endophytic fungus isolated from Delphinium grandiflorum L. Their structures were elucidated mainly by extensive analyses of NMR and MS spectroscopic data. In addition, the screening results of antibacterial and cytotoxic activities of compounds 1-15 showed that compound 4 displayed antibacterial activities against Staphylococcus aureus and MRSA (methicillin-resistant S. aureus) with an MIC value of 3.12 µg/mL.

Ochrolines A-C, three new indole diketopiperazines from cultures of endophytic fungi Bionectria ochroleuca SLJB-2.

Three new indole diketopiperazines, ochrolines A-C (1-3), along with three known compounds (4-6), were isolated and identified from the EtOAc extract of the solid fermentation of Bionectria ochroleuca SLJB-2. Notably, compound 1 featured a natural rarely-occurring caged skeleton with a 6/5/6/7 heterotetracyclic bridged ring system. The structures including absolute configurations of 1-3 were fully accomplished by extensive spectroscopic analyses, DFT GIAO 13C NMR and electronic circular dichroism (ECD) calculations. The plausible biogenetic pathways of these new indole diketopiperazines were also proposed. Moreover, the cytotoxic activity screening revealed that compound 2 exhibited moderate inhibitory effect against A549 with inhibition rate of 57.44% at the concentration of 50 µM and compound 1 exhibited mild inhibitory activities against A549, Hela and MCF-7.

Koningipyridines A and B, two nitrogen-containing polyketides from the fungus Trichoderma koningiopsis SC-5.

Two novel koninginin derivatives, koningipyridines A and B (1 and 2), along with four known compounds (3-6) were isolated from the EtOAc extract of the endophytic fungus Trichoderma koningiopsis SC-5. Among them, koningipyridine A featured an unprecedented pentacyclic ketal skeleton with the formation of a fascinating 6/6/5/6/5 fused ring system and shared a characteristic pyridine core, which represents the first example of nitrogen-containing koninginin-type natural product. Moreover, koningipyridine B was the first member in the koninginin family sharing a unique 6/6/5 dihydropyridine skeleton, and it was suggested to be the critical biosynthetic precursor of koningipyridine A. The structures of 1 and 2 were elucidated by the interpretation of 1D and 2D NMR spectroscopy, HRESIMS data, as well as theoretical calculations of 13C NMR and electronic circular dichroism (ECD). Moreover, all isolates were screened for antimicrobial activities against Staphylococcus aureus, MRSA, and Escherichia coli as well as the cytotoxic effects against three cancer cell lines (A549, Hela, and HepG2).

Koninginins X-Z, Three New Polyketides from Trichoderma koningiopsis SC-5.

Koninginins X-Z (1-3), three novel polyketides, were isolated from the solid fermentation of the endophytic fungus Trichoderma koningiopsis SC-5. Their structures, including the absolute configurations, were comprehensively characterized by a combination of NMR spectroscopic methods, HRESIMS, 13C NMR, DFT GIAO 13C NMR, and electronic circular dichroism calculations as well as single crystal X-ray diffraction. In addition, all the compounds were evaluated for antifungal activity against Candida albicans.

Three new metabolites from the endophyte Fusarium proliferatum T2-10.

One new cyclopeptide, cyclo-(L-Trp-L-Phe-L-Phe) (1), one new 2-pyridone derivative, fusarone A (3), and one new natural indole derivative, ethyl 3-indoleacetate (4), along with six known compounds were isolated from the endophytic fungus Fusarium proliferatum T2-10. The planar structures of three new compounds were identified by spectral methods including 1D and 2D NMR techniques, and the absolute configuration of compound 1 was elucidated by Marfey-MS method. In addition, all compounds were evaluated for their cytotoxic and antibacterial activities in vitro. Compound 2 showed remarkable cytotoxic activities against two human hepatoma cell lines SMMC7721 and HepG2 with IC50 values of 5.89 ± 0.74 and 6.16 ± 0.52 µM, and showed moderate antibacterial activities against Staphylococcus aureus and Enterococcus faecalis with MIC values of 7.81 and 15.62 µg/mL, respectively.

Validity and reliability of the physical activity and social support scale among Chinese established adults.

Social support is a crucial factor that can facilitate regular engagement in physical activity. To assess the influence of social factors on the level of regular physical activity, the Physical Activity and Social Support Scale (PASSS) has been developed. However, the PASSS has yet to be validated in a Chinese sample of established adults. To address this gap in the literature, this study describes the development and psychometric evaluation of a Chinese version of the PASSS (PASSS-C) for established adults. PASSS-C was validated for a Chinese sample of adults aged between 30 and 45 years old (N = 1799). Structural validity was evaluated using confirmatory factor analysis (CFA) with Maximum Likelihood Method (MLM). Spearman's correlations between the PASSS-C and the International Physical Activity Questionnaire - Short Form (IPAQ-SF), the Social Support Rating Scale - Chinses Version (SSRS-C), and the Affective Exercise Experience Scale - Chinese Version (AFFEXX-C) were determined to examine the criterion validity. Cronbach's alpha coefficients and McDonald's omega coefficients were used to assess the internal consistency of the total scale and sub-scales of the PASSS-C. The results of the CFA suggest that the five-factor model had an acceptable fit (CFI = 0.99, GFI = 0.99, SRMR = 0.01, RMSEA = 0.02). Cronbach's alpha and McDonald's omega for the PASSS-C and its sub-scales ranged from 0.81 to 0.96. The results indicate that the PASSS-C has acceptable psychometric properties. Thus, the scale can be used to assess the levels of social support for physical activity in Chinese established adults.

Two new secondary metabolites isolated from the fungus Penicillium virgatum T49-A.

The extensively chemical investigation of the EtOAc extract of the soil fungus Penicillium virgatum T49-A has successfully led to the isolation of two undescribed secondary metabolites penivirtone A (1) and peniviramide B (2) together with six known compounds. Their chemical structures including the absolute configurations of the two new compounds were comprehensively established by extensive analyses of NMR and HRESIMS spectra as well as ECD powered by theoretical calculations. Moreover, the cytotoxic and antibacterial activities of compounds 1-2 were also evaluated, whereas the two novel compounds showed no notable cytotoxic and antibacterial activities.

Design, synthesis and evaluation of nitric oxide releasing derivatives of 2,4-diaminopyrimidine as novel FAK inhibitors for intervention of metastatic triple-negative breast cancer.

To search for novel medicines for intervention of triple-negative breast cancer (TNBC), a series of phenylsulfonyl furoxan-based 2,4-diaminopyrimidine derivatives (8a-t) were designed and synthesized based on blocking FAK-mediated signaling pathways through both kinase-dependent and -independent manners. The most active compound 8f not only significantly inhibited FAK kinase activity (IC50 = 27.44 nM), displayed potent inhibitory effects on the proliferation (IC50 = 0.126 µM), invasion and migration of MDA-MB-231 cells, superior to the most widely studied FAK inhibitor, TAE226, bearing 2,4-diaminopyrimidine, but also released high levels of NO, contributing to blockage of FAK mediated-signaling pathways by upregulating of p53 as well as suppressing the Y397 phosphorylation and its downstream effectors, including p-Akt, MMP-2, and MMP-9 via kinase-independent manner, leading to apoptosis induction and decrease of FAs and SFs in TNBC cells. Importantly, 8f inhibited the lung metastasis of TNBC in vivo. Together, 8f may serve as a promising candidate for the treatment of metastatic TNBC.

Betulinaldehyde exhibits effective anti-tumor effects in A549 cells by regulating intracellular autophagy.

It is of great significance to find new effective drugs for an adjuvant therapy targeting lung cancer to improve the survival rate and prognosis of patients with the disease. Previous studies have confirmed that certain Chinese herbal extracts have clear anti-tumor effects, and in our preliminary study, betulinaldehyde was screened for its potential anti-tumor effects. The current study thus aimed to confirm the anti-tumor effect of betulinaldehyde, using in vitro experiments to explore its underlying molecular mechanism. It was found that betulinaldehyde treatment significantly inhibited the viability, proliferation, and migration of A549 cells in a dose-dependent manner. In addition, betulinaldehyde inhibited the activation of Akt, MAPK, and STAT3 signaling pathways in A549 cells in a time-dependent manner. More importantly, betulinaldehyde also decreased the expression level of SQSTM1 protein, increased the expression level of LC3 II, and increased the autophagy flux in A549 cells. The pretreatment of A549 cells with the autophagy inhibitor, 3-methyladenine, could partially negate the anti-tumor effects of betulinaldehyde. These findings suggest that betulinaldehyde could significantly inhibit the oncological activity of A549 cells by regulating the intracellular autophagy level, making it a potentially effective option for the adjuvant therapy used to treat lung cancer in the future.

Contextual Features and Information Bottleneck-Based Multi-Input Network for Breast Cancer Classification from Contrast-Enhanced Spectral Mammography.

In computer-aided diagnosis methods for breast cancer, deep learning has been shown to be an effective method to distinguish whether lesions are present in tissues. However, traditional methods only classify masses as benign or malignant, according to their presence or absence, without considering the contextual features between them and their adjacent tissues. Furthermore, for contrast-enhanced spectral mammography, the existing studies have only performed feature extraction on a single image per breast. In this paper, we propose a multi-input deep learning network for automatic breast cancer classification. Specifically, we simultaneously input four images of each breast with different feature information into the network. Then, we processed the feature maps in both horizontal and vertical directions, preserving the pixel-level contextual information within the neighborhood of the tumor during the pooling operation. Furthermore, we designed a novel loss function according to the information bottleneck theory to optimize our multi-input network and ensure that the common information in the multiple input images could be fully utilized. Our experiments on 488 images (256 benign and 232 malignant images) from 122 patients show that the method's accuracy, precision, sensitivity, specificity, and f1-score values are 0.8806, 0.8803, 0.8810, 0.8801, and 0.8806, respectively. The qualitative, quantitative, and ablation experiment results show that our method significantly improves the accuracy of breast cancer classification and reduces the false positive rate of diagnosis. It can reduce misdiagnosis rates and unnecessary biopsies, helping doctors determine accurate clinical diagnoses of breast cancer from multiple CESM images.

Porric acid E, a natural compound from Rhytidhysteron sp. BZM-9, suppresses colorectal cancer growth via an autophagy-dependent pathway.

Colorectal cancer (CRC) is one of the major killer diseases worldwide, and more effective therapeutic compounds for CRC treatment are urgently needed. Although bioactive natural products derived from endophytic fungi have been extensively employed as antibiotics and anticancer agents, little is known about the effect of Rhytidhysteron sp. BZM-9 (an endophytic fungus)-derived compounds on CRC. Herein, a natural molecule porric acid E was isolated from Rhytidhysteron sp. BZM-9. Alamar Blue cell viability assay, Western blotting, transmission electron microscopy, flow cytometry analysis, and fluorescence image examination were employed to evaluate the antitumor effects of porric acid E on CRC cell lines. To establish the xenograft tumor model, nude mice received subcutaneous implants consisting of CRC cells on their flanks. Then the mice were treated with porric acid E or vehicle to assess the tumor-killing effects. The results revealed that porric acid E exhibited cytotoxicity by inhibiting proliferation and promoting apoptosis in CRC cells in vitro. Additionally, compared with fluorouracil (5-FU), porric acid E exhibited a more potent inhibitory effect on CRC HT29 cells. Importantly, extensive autophagy induced by porric acid E was detected in CRC cells, whereas inhibition of autophagy could significantly ameliorate porric acid E-mediated cytotoxic effect on CRC cells. Moreover, porric acid E treatment could markedly suppress subcutaneous HT29 xenograft tumor growth in vivo. Bioinformatics prediction indicated that Beclin-1 might be the potential target of porric acid E. These findings might afford a useful and important method for the treatment of CRC through fungal endophyte-derived natural compounds.

Five new secondary metabolites from an endophytic fungus Phomopsis sp. SZSJ-7B.

Two previously undescribed lactones, phomolides A and B (1 and 2), and three new sesquiterpenoids, phomenes A-C (3-5), together with one known compound, colletotricholide A (6), were isolated from the endophytic fungus Phomopsis sp. SZSJ-7B. Their chemical structures, including the absolute configurations, were comprehensively established by extensive analyses of NMR, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism powered by theoretical calculations, and X-ray diffractions. Moreover, the cytotoxic and antibacterial activities of compounds 1-6 were also evaluated, and the results demonstrated that compound 2 showed significant antibacterial effects towards methicillin-resistant Staphylococcus aureus and S. aureus strains with minimum inhibitory concentration as low as 6.25 µg/ml, which was comparable to that of the clinical drug vancomycin. Moreover, all compounds showed no cytotoxic activity.

Two new chromone derivatives from the rhizosphere soil fungus Ilyonectria robusta.

Two new chromone derivatives (1 and 2), and two known compounds (3 and 4) were isolated from the rhizosphere soil fungus Ilyonectria robusta. Their planar structures and absolute configurations were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. Additionally, all the isolated compounds were evaluated for their antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli, but no obvious activity was observed at a concentration of 128 µg/mL.

Pseudocercones A-C, three new polyketide derivatives from the endophytic fungus Pseudocercospora sp. TSS-1.

Chemical investigation of an EtOAc extract of the endophytic fungus Pseudocercospora sp. TSS-1 led to the isolation of three new polyketide derivatives, including one benzophenon derivative (1), two spirocyclic polyketides (4 and 5), along with four known compounds (2, 3, 6 and 7). Their structures and the absolute configurations were characterized by means of NMR, HRESIMS, 13C NMR and theoretical electronic circular dichroism calculations. Furthermore, all compounds were evaluated for their antibacterial activity against four microbial pathogens (Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli), and compounds 1, 2, 3 and 5 displayed significant selective antibacterial activity against S. aureus with MIC values ranging from 3.9 to 7.8 µg/mL.

Value of Artificial Neural Network Ultrasound in Improving Breast Cancer Diagnosis.

Ultrasound-guided needle biopsy based on artificial neural network, as a safe, effective, and simple preoperative pathological diagnosis technique, has been widely used in clinical practice. Ultrasound-guided needle biopsy based on artificial neural networks for suspicious breast lesions found in conventional ultrasound examinations is an effective method for preoperative diagnosis. The purpose of this article is to study the value of artificial neural network ultrasound in improving breast cancer diagnosis. This article summarizes the neuron model of PCNN by observing and studying its impulse synchronization phenomenon. Aiming at gray-scale images disturbed by mixed noise (impulse noise and the Gaussian noise), a comprehensive filtering algorithm based on the simplified PCNN model is proposed. In this paper, the benign and malignant breast masses were evaluated based on the two-dimensional and three-dimensional ultrasound imaging signs of the mass, and compared with the postoperative pathological results, a logistic regression model was established to analyze the shape, boundary, microcalcification, and posterior echo attenuation of the mass, values for keratinization or burrs, convergent signs, and blood flow classification in the differential diagnosis of benign and malignant. In this paper, a color ultrasound diagnostic device is used, Sonobi is used as a contrast medium, and the injection volume is 2.4 ml/dose. During the imaging process, the sound image performance of the lesion is dynamically observed, the original dynamic data are stored throughout the whole process, and the playback analysis is performed after the imaging is completed. Studies have shown that CDUS elastography (UE) combined with MRI can increase the sensitivity of breast cancer diagnosis, with a diagnostic accuracy rate of 92.4%.

Neocucurbols A-H, Phomactin Diterpene Derivatives from the Marine-Derived Fungus Neocucurbitaria unguis-hominis FS685.

Neocucurbols A-D (1-4) are diterpene derivatives that possess a complex 6/6/5/5/6 polycyclic ring system with a characteristic tetrahedrofuran bridge ring skeleton. Neocucurbols E-H (5-8) are diterpenes that feature a 6/8/6 tricyclic ring system. Their structures were unambiguously determined by detailed spectroscopic analyses, X-ray diffractions studies, and ECD calculations. All compounds (1-8) were evaluated for in vitro antimicrobial and cytotoxic activities.

Discovery of novel chloropyramine-cinnamic acid hybrids as potential FAK inhibitors for intervention of metastatic triple-negative breast cancer.

To search for novel focal adhesion kinase (FAK) inhibitors for intervention of metastatic triple-negative breast cancer (TNBC), a series of hybrids 7a-s from chloropyramine and cinnamic acid analogs were designed, synthesized and biologically evaluated. The most active compound 7d could potently inhibit the proliferation, invasion and migration of TNBC cells in vitro. The docking analysis of 7d was performed to elucidate its possible binding modes to focal adhesion targeting (FAT) domain of FAK scaffold. Further mechanism studies indicated the ability of 7d in disrupting Y925 autophosphorylation of FAK, reducing formation of focal adhesions (FAs) and stress fibers (SFs) as well as inducing apoptosis of TNBC cells. Together, 7d is a novel FAK inhibitor to inhibit the essential nonkinase scaffolding function of FAK via binding FAT domain and may be worth studying further for intervention of TNBC.