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Abstract Hormone receptor-positive breast cancer (BC) is the most prevalent subtype of BC and is generally correlated with a favorable prognosis. This study aimed to determine the incidence and survival trends among women diagnosed with hormone receptor-positive BC between 1990 and 2019. Female patients with hormone receptor-positive BC for calendar years 1990–2019 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database and categorized into six diagnostic groups according to the year of diagnosis. Age-adjusted incidence rates (IRs) were calculated using joinpoint regression. We used the Kaplan–Meier method and multivariate Cox regression analyses to determine the association between diagnostic groups, and overall survival (OS) and BC-specific survival (BCSS). The final analysis included 370,729 women, among whom 37,943 (10.2%), 49,266 (13.3%), 55,652 (15.0%), 64,451 (17.4%), 77,127 (20.8%), and 86,290 (23.3%) were diagnosed between 1990 and 1994, 1995–1999, 2000–2004, 2005–2009, 2010–2014, and 2015–2019, respectively. Within the overall cohort, IRs gradually increased from 70 per 100,000 in 1990 to 113 per 100,000 in 2019 (average annual percent change, 1.59%; 95% CI, 1.18–1.99). Multivariate Cox regression analysis revealed that the survival outcomes gradually improved over nearly three decades among hormone receptor-positive BC patients, with a 0.8% and 1.3% decrease in risk for all-cause and BC-specific mortality each year, respectively. Compared to 1990–1994, hormone receptor-positive BC patients diagnosed in 2015–2019 had a 22% lower risk of all-cause death (hazard ratio [HR], 0.78; 95% CI, 0.76–0.81) and a 27% lower risk of BC-specific death (HR, 0.73; 95% CI, 0.70–0.76). The development of treatment strategies within the past three decades, especially endocrine therapy, may contribute to the continuous improvement of clinical outcomes in patients with hormone receptor-positive BC.

Abstract Background Racial and ethnic disparities in mortality persist among US cancer survivors, with social determinants of health (SDoH) may have a significant impact on these disparities. Methods A population-based cohort study of a nationally representative sample of adult cancer survivors, who participated in the US National Health and Nutrition Examination Survey from 1999 to 2018 was included. Sociodemographic characteristics and SDoH were self-reported using standardized questionnaires in each survey cycle. The SDoH was examined by race and estimated for associations with primary outcomes, which included all-cause and cancer-specific mortality. Multiple mediation analysis was performed to assess the contribution of each unfavorable SDoH to racial disparities to all-cause and cancer-specific mortality. Results Among 5163 cancer survivors (2724 [57.7%] females and 3580 [69.3%] non-Hispanic White individuals), only 881 (24.9%) did not report an unfavorable SDoH. During the follow-up period of up to 249 months (median 81 months), 1964 deaths were recorded (cancer, 624; cardiovascular, 529; other causes, 811). Disparities in all-cause and cancer-specific mortality were observed between non-Hispanic Black and White cancer survivors. Unemployment, lower economic status, education less than high school, government or no private insurance, renting a home or other arrangements, and social isolation were significantly and independently associated with worse overall survival. Unemployment, lower economic status, and social isolation were significantly associated with cancer-specific mortality. Compared to patients without an unfavorable SDoH, the risk of all-cause mortality was gradually increased in those with a cumulative number of unfavorable SDoHs (1 unfavorable SDoH: hazard ratio [HR] = 1.54, 95% CI 1.25–1.89; 2 unfavorable SDoHs: HR = 1.81, 95% CI 1.46–2.24; 3 unfavorable SDoHs: HR = 2.42, 95% CI 1.97–2.97; 4 unfavorable SDoHs: HR = 3.22, 95% CI 2.48–4.19; 5 unfavorable SDoHs: HR = 3.99, 95% CI 2.99–5.33; 6 unfavorable SDoHs: HR = 6.34 95% CI 4.51–8.90). A similar trend existed for cancer-specific mortality. Conclusions In this cohort study of a nationally representative sample of US cancer survivors, a greater number of unfavorable SDoH was associated with increased risks of mortality from all causes and cancer. Unfavorable SDoH levels were critical risk factors for all-cause and cancer-specific mortality, as well as the underlying cause of racial all-cause mortality disparities among US cancer survivors.

Abstract Rainbow trapping, observed in elastic waves, has attracted considerable scientific interest owing to its potential applications in energy harvesting, buffering, and wavelength-division multiplexing devices. However, previous approaches have often necessitated complex geometric modifications to the scatterer, such as altering dimensions or shifting along diagonals to corners, limiting practical utility. Here, we realize the coupled topological edge states (CTESs) of elastic waves in a two-dimensional (2D) solid phononic crystal (PC) with inversion center changes. Changing the inversion center along the x or y directions by a specific distance can induce the topological phase transition. The topological edge states (TESs) arise at the interface by combining PCs with different topologies positioned adjacent to each other. Furthermore, it is demonstrated that TES exhibits topological robustness against defects. By introducing a gradient into the PC structure by altering the geometrical parameters of scatterers along the interface, the topological rainbow trapping of elastic waves is achieved. Finally, the CTES are generated by the interaction between TESs of different interfaces, which can lead to coupled topological rainbow trapping in phononic heterostructures with different displacement parameters along the multiple interface gradient. Our results pave the way for manipulating the symmetric and antisymmetric topological modes of elastic waves in topologically coupled waveguides, which offers potential applications in selective filtering and multiband waveguiding.

Abstract Background Glioblastoma multiforme (GBM) is the most aggressive form of brain cancer, and chemoresistance poses a significant challenge to the survival and prognosis of GBM. Although numerous regulatory mechanisms that contribute to chemoresistance have been identified, many questions remain unanswered. This study aims to identify the mechanism of temozolomide (TMZ) resistance in GBM. Methods Bioinformatics and antibody-based protein detection were used to examine the expression of E2F7 in gliomas and its correlation with prognosis. Additionally, IC50, cell viability, colony formation, apoptosis, doxorubicin (Dox) uptake, and intracranial transplantation were used to confirm the role of E2F7 in TMZ resistance, using our established TMZ-resistance (TMZ-R) model. Western blot and ChIP experiments provided confirmation of p53-driven regulation of E2F7. Results Elevated levels of E2F7 were detected in GBM tissue and were correlated with a poor prognosis for patients. E2F7 was found to be upregulated in TMZ-R tumors, and its high levels were linked to increased chemotherapy resistance by limiting drug uptake and decreasing DNA damage. The expression of E2F7 was also found to be regulated by the activation of p53. Conclusions The high expression of E2F7, regulated by activated p53, confers chemoresistance to GBM cells by inhibiting drug uptake and DNA damage. These findings highlight the significant connection between sustained p53 activation and GBM chemoresistance, offering the potential for new strategies to overcome this resistance.

Abstract Purpose To use 18 F-FDG microPET dynamic imaging to preliminarily identify the changes of myocardial glucose metabolism corresponding to different functional phenotypes of diabetic cardiomyopathy (DCM) in mice and elucidate their relationships. Methods Left ventricular function was measured by echocardiography in C57BL/KsJ-db/db (db/db) mice and their controls at 8, 12, 16, and 20 weeks of age to divide DCM stages and functional phenotypes. Myocardial histopathology was used to verify the staging accuracy and list-mode microPET dynamic imaging was conducted. The myocardial metabolic rate of glucose (MRglu) and the glucose uptake rate constant (Ki) were derived via Patlak graphical analysis, and the differences in myocardial glucose metabolism levels in different DCM stages were compared. The key proteins involved in myocardial glucose metabolism signaling pathway were analyzed by Western blotting to elucidate the underlying mechanism of abnormal glucose metabolism in DCM. Results Compared with the controls, the ratio of early diastolic transmitral flow velocity to early diastolic mitral annular tissue velocity (E/e’) of db/db mice was significantly increased from the age of 12 weeks, while the left ventricular ejection fraction (LVEF) was significantly decreased from the age of 16 weeks (all P 0.05). MRglu and SUV were moderately negatively correlated with the E/e’ ratio (r=-0.539 and − 0.512, P = 0.007 and 0.011), which were not significantly correlated with LVEF (P > 0.05). Meanwhile, Ki was not significantly correlated with LVEF or E/e’ ratio. The decreased expression of glucose transporter (GLUT) -4 in db/db mice preceded GLUT-1 and was accompanied by decreased phosphorylated AMP-activated protein kinase (p-AMPK) expression. Myocardial MRglu, Ki and SUV were significantly positively correlated with the expression of GLUT-4 (MRglu: r = 0.537; Ki: r = 0.818; SUV: r = 0.491; P = 0.000 ~ 0.046), but there was no significant correlation with GLUT-1 expression (P = 0.238 ~ 0.780). Conclusions During the progression of DCM, with the changes of left ventricular functional phenotype, abnormal and dynamic changes of myocardial glucose metabolism can occur in the early stage.

BackgroundGene chip technology has been increasingly used in the diagnosis and treatment of common tuberculosis. However, its role in the diagnosis and treatment of silicosis complicated with mycobacterial infection remains unclear. ObjectiveTo evaluate the application value of gene chip technology in the diagnosis and treatment of silicosis complicated with mycobacterial infection. MethodsFrom January 2019 to June 2021, 197 silicosis patients suspected to be complicated with mycobacterial infection in Quanzhou First Hospital Affiliated to Fujian Medical University were enrolled in this study. The etiology evaluation for the 197 patients was conducted by acid-fast staining of sputum smear (sputum smear method), culture of Mycobacterium tuberculosis of sputum (sputum culture method), and gene chip technology of bronchoalveolar lavage fluid (BALF); and for 80 patients among them, acid-fast staining of BALF (BALF smear method) and culture of Mycobacterium tuberculosis of BALF (BALF culture method) were additionally performed. The positive rates and consistency were assessed using intraclass correlation coefficient (ICC). Test for Mycobacterium tuberculosis drug resistance mutation gene was added for patients with Mycobacterium tuberculosis complex by BALF gene chip technology. ResultsThe average age of the 197 patients was (53.1±9.1) years, and the average dust exposure time was (21.1±9.4) years, including 192 males and 5 females. There were 8 cases with stage I silicosis, 17 cases with stage II silicosis, and 172 cases with stage III silicosis. Among them, 11.2% were positive for sputum smear; 24.4% were positive for sputum culture, and 36.0% were positive by gene chip of BALF. The difference between the three methods was statistically significant (P0.05). The result of consistency test for the five methods showed that the ICC was 0.586 (P

Recently, we re-isolated the glycosylated angucycline antibiotics P-1894B (1) and grincamycin (1′) from the marine-derived Streptomyces lusitanus SCSIO LR32 as potent antitumor agents and identified their biosynthesis gene cluster gcn. Both P-1894B (1) and grincamycin (1′) possess a trisaccharide and a disaccharide moiety comprised of five deoxysugars. In this work, three genes encoding glycosyltransferases (GcnG1, GcnG2, and GcnG3) responsible for the assembly of deoxysugars into angucycline aglycone were identified from the biosynthesis gene cluster gcn. Gene inactivations of gcnG1, gcnG2, gcnG3, and gcnG1G2 by lambda-RED-mediated gene replacements led to the construction of four mutants, in which the glycosyltransferase genes were disrupted, respectively. The metabolites from the mutants were purified and identified, including two new analogues designated as grincamycin U (3a) and V (3′). The sequential glycosylation steps in the biosynthesis of P-1894B (1) and grincamycin (1′) catalyzed by GcnG3, GcnG1, and GcnG2 were elucidated.

Seven new polyketides named fusarisolins F-K (1–6) and fusarin I (7) were isolated from the marine-derived fungus Fusarium solani 8388, together with the known anhydrojavanicin (8), 5-deoxybostry coidin (9), and scytalol A (10). Their structures were established by comprehensive spectroscopic data analyses, and by comparison of the 1H and 13C NMR data with those reported in literature. Fusarisolin F (1) contained both a dichlorobenzene group and an ethylene oxide unit, which was rare in nature. In the bioassays, fusarisolin I (4), fusarisolin J (5), and 5-deoxybostry coidin (9) exhibited obvious antibacterial activities against methicillin-resistant Staphylococcus aureus n315 with MIC values of 3, 3, and 6 μg/mL, respectively. Fusarisolin H (3) and fusarisolin J (5) showed inhibitory effects against methicillin-resistant Staphylococcus aureus NCTC 10442 with the same MIC value of 6 μg/mL. With the exception of 5, all other compounds did not show or showed weak cytotoxicities against HeLa, A549, and KB cells; while fusarisolin J (5) demonstrated moderate cytotoxicities against the three human cancer cell lines with CC50 values between 9.21 and 14.02 μM.

BackgroundSpontaneous coronary artery dissection (SCAD) is a rare coronary artery disease that frequently occurs in young, female patients without risk factors, and conservative treatment is often recommended for its management. The patient reported here is a male patient with systemic lupus erythematosus (SLE).Case summaryWe described a 28-year-old man with SLE who presented with acute ST-segment elevation myocardial infarction (STEMI), and was diagnosed with SCAD through a long dissection of the left anterior descending branch (LAD) by coronary angiography. The patient was treated with percutaneous coronary intervention (PCI) with stent implantation. Ten years later, he developed in-stent stenosis and other coronary atherosclerosis and was retreated with PCIs. Based on this case and according to the literature review, the existing treatment and prognosis of SLE with spontaneous coronary artery dissection and atherosclerosis are discussed.ConclusionCardiovascular complications should be considered in patients with systemic lupus erythematosus, although they may not initially be atherosclerotic diseases. Attention should be paid to distinguish spontaneous coronary dissection in order to minimize missed or delayed diagnoses and take appropriate managements, as well as the development of atherosclerosis in SLE patients, and timely intervention has a better prognosis.

The combination of thermal power and hybrid energy storage is an effective way to improve the response ability of automatic generation control (AGC) command in thermal power plants. Notably, the configuration of hybrid energy storage capacity is directly related to improvement of the frequency modulation ability of thermal power plants and the coordination of economic benefits. However, the constant efficiency model adopted in capacity configuration will misjudge the actual operating status of each energy storage unit, resulting in unreasonable capacity allocation. In this context, a fire-storage capacity optimization configuration model considering the dynamic charge–discharge efficiency of hybrid energy storage is established. The model presents the functional relationship between charge and discharge power and the efficiency of different types of energy storage. Simulation proves that the proposed strategy can meet the tracking demand of area control error signal in thermal power plants and reduce the planning and operation cost of energy storage.

Abstract Background Proteinuria is one of the common manifestations of patients with preeclampsia (PE), but whether the severity of proteinuria is related to the pregnancy outcome of patients with preeclampsia remains controversial. The present study aimed to determine the relationship between 24-h proteinuria and adverse outcomes in patients with preeclampsia. Methods The present retrospective study included 329 pregnant women in Chongqing, China. Patients were divided into PE group and non-PE group. PE group was stratified into three subgroups based on the level of 24-h proteinuria. Correlation analysis was used to analyze the correlation between biochemical indexes and adverse pregnancy outcome, and Logistic regression analysis was used to analyze the risk factors of adverse pregnancy outcome. The receiver operating characteristic curve (ROC) was used to evaluate the ability of 24-h urinary protein to distinguish the adverse pregnancy outcome in patients with preeclampsia. Results (1) Between PE and non-PE group, cesarean section rate in PE group was significantly higher than that in non-PE group (84.4% vs. 25.9%, p

Abstract. Coronavirus disease 2019 (COVID-19) has spread throughout China. However, information about COVID-19 in cities and regions outside Wuhan is limited and the indicators that predict the length of hospital stay for patients with COVID-19 are unclear. Therefore, we collected clinical data from 47 patients with COVID-19 in Quanzhou City. The median age was 38 years [interquartile range (IQR): 31–50 years], and 24 (51%) were male. There were 8 mild, 36 moderate, and 3 severe/critical cases. The median interval from exposure to disease onset was 13 days (IQR: 8–18 days). The incidence of severe/critical cases was 33% (3/10) in patients with hypertension. Common symptoms included fever (83%), cough (77%), fatigue (40%), a sore, dry throat (28%), and diarrhea (21%). One patient (2%) developed respiratory distress syndrome on day 13 of inpatient treatment. Six patients had leukopenia, 17 had elevated C-reactive protein (CRP), and 8 had lymphocytopenia and elevated lactate dehydrogenase (LDH). The median length of hospitalization was 22 days (IQR: 16-30 days). Dynamic monitoring of LDH, CRP, and neutrophil-lymphocyte ratio predicted whether length of hospitalization would exceed 21 days. Most patients presented with mild and moderate disease. Patients with hypertension were more likely to become severe or critical. Dynamic monitoring of LDH, CRP, and neutrophil-lymphocyte ratio levels can help predict delayed discharge from the hospital.

Abstract To determine factors associated with delayed discharge of hospitalized patients with coronavirus disease (COVID-19). This retrospective cohort study included 47 patients with COVID-19 admitted to three hospitals in Quanzhou City, Fujian Province, China, between January 21, 2020 and March 6, 2020. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with delayed discharge. The median length of hospital stay was 22 days. Patients in the delayed discharge group (length of hospital stay ≥ 21 days, n = 27) were more likely to have diarrhea, anorexia, decreased white blood cell counts, increased complement C3 and C-reactive protein levels, air bronchograms, undergo thymalfasin treatment, and take significantly longer to convert to a severe acute respiratory syndrome coronavirus (SARS-CoV-2) RNA-negative status than those in the control group (length of hospital stay,

Platelet-derived exosomes (PLT-Exos) are the main subtype of extracellular vesicles secreted by platelets, which carry proteins, nucleotides, lipids, and other substances to acceptor cells, playing an important role in intercellular communication. PLT-Exos increase with platelet activation and are involved in the process of atherothrombosis by delivering cargo to acceptor cells. Atherosclerotic plaque rupture, causing thrombosis and arterial occlusion, is the basic pathological change leading to cardiovascular events. PLT-Exos from different donors have different functions. PLT-Exos secreted by healthy volunteer or mice can inhibit platelet activation and inflammation of endothelial cells, thus exerting an antithrombotic effect, while PLT-Exos derived from some patients induce endothelial apoptosis and an inflammatory response to promote atherothrombosis. Furthermore, increased PLT-Exos reflect platelet activation and their cargoes also are derived from platelets; therefore, PLT-Exos can also be used as a biomarkers for the diagnosis and prognosis of cardiovascular disease. This article reviews the characteristics of PLT-Exos and discusses their role in cell-to-cell communication and atherothrombosis.

Background. Nei endonuclease VIII-like 3 (NEIL3) is widely involved in pathophysiological processes of the body; however, its role in lung cancer has not been conclusively determined. Objective. This study is aimed at exploring the role of NEIL3 in lung cancer. Methods. The public data used in this study were downloaded from The Cancer Genome Atlas (TCGA) database. “Limma” in R was used for the analysis of differentially expressed genes. Clinical correlations and prognostic analyses were performed using the survival package in R. The proliferative abilities of lung cancer cells were evaluated by the CCK8 and colony formation assays while their invasive and migration abilities were assessed by the transwell and wound healing assays. Quantitative real-time PCR (qRT-PCR) and western blot analyses were utilized to detect RNA and protein levels. Biological differences between groups were determined by gene set enrichment analysis (GSEA). Tumor Immune Dysfunction and Exclusion (TIDE) as well as Genomics of Drug Sensitivity in Cancer (GDSC) was used for immunotherapeutic and chemotherapeutic sensitivity analyses. Results. NEIL3 was upregulated in NSCLC tissues and cell lines, implying that it is involved in lung cancer initiation and progression. Clinical correlation and prognostic analyses showed that NEIL3 was associated with worse clinical features (stage and T and N classifications) and poor prognostic outcomes. In vitro, NEIL3 significantly enhanced NSCLC proliferation, invasion, and migration. GSEA indicated that NEIL3 might be involved in PI3K/AKT/mTOR, G2/M checkpoints, and E2F target pathways. Inhibition of NEIL3 suppressed cyclinD1 and p-AKT protein levels; however, it had no effects on AKT levels, indicating that NEIL3 can partially activate the PI3K/AKT/mTOR signaling pathway. The predicted result of TIDE indicated that immunotherapeutic nonresponders had elevated NEIL3 levels. Moreover, there was a positive correlation between NEIL3 levels and chemosensitivity to cisplatin and paclitaxel. Conclusion. In general, NEIL3 mediates NSCLC progression and affects sensitivity to immunotherapy and chemotherapy; therefore, it is a potential molecular target for treatment.

Tuberculosis (TB) remains one of the world’s deadliest communicable diseases, novel anti-TB agents are urgently needed due to severe drug resistance and the co-epidemic of TB/HIV. Here, the authors show that anti-mycobacterial ilamycin congeners bearing unusual structural units possess extremely potent anti-tuberculosis activities.

Topological interface states have attracted extensive research interest due to their unprecedented field confinement and enhancement at the interface between two one-dimensional phononic crystals with distinct topological characteristics. However, the realization of the contactless, nondestructive, and intelligent tunability of topological interface states, as the foundation for designing novel devices with unconventional functionalities, still remains a great challenge. Here, we introduce intelligent magnetoelastic materials to the topological system and realize magnetically tunable topological interface states for Lamb waves in one-dimensional phononic crystal slabs composed of alternating nonmagnetic and magnetoelastic layers. The properties of magnetoelastic layers can be tuned with noncontact, nondestruction, and intelligence by an external magnetic field. By changing the value of the external magnetic field applied on intercell and intracell magnetoelastic layers, the spatial variation of the properties of magnetoelastic layers is induced, resulting in an in situ topological phase transition. We demonstrate that topological interface states appear at the interface between two topologically different magnetoelastic phononic crystal slabs. Furthermore, based on the tunability of the external magnetic field, the existence of topological interface states can be switched and the frequency of topological interface states can be continuously tuned. In particular, the arbitrary positions of topological interface states can be dynamically achieved by varying the external magnetic field without altering the structure. Our tunable topological system can enable intelligent Lamb-wave devices with remarkable functionalities, which can lead to significant advances in intelligently controlled Lamb-wave switches, magnetically tunable frequency selectors, and magnetic control Lamb-wave communications.

Two new C-glycoside angucyclines, marangucycline A (1) and marangucycline B (2), along with three known compounds, dehydroxyaquayamycin (3), undecylprodigiosin (4) and metacycloprodigiosin (5), have been identified as products of the deep-sea sediment strain Streptomyces sp. SCSIO 11594. New structures were elucidated on the basis of HRESIMS, 1D and 2D NMR analyses and comparisons to previously reported datasets. Compounds 2 and 4 displayed in vitro cytotoxicity against four cancer cell lines A594, CNE2, HepG2, MCF-7 superior to those obtained with cisplatin, the positive control. Notably, compound 2 bearing a keto-sugar displayed significant cytotoxicity against cancer cell lines with IC50 values ranging from 0.24 to 0.56 μM; An IC50 value of 3.67 μM was found when using non-cancerous hepatic cell line HL7702, demonstrating the cancer cell selectivity of 2. Compounds 1–3 were proved to have weak antibacterial activities against Enterococcus faecalis ATCC29212 with an MIC value of 64.0 μg/mL. Moreover, 3 displayed selective antibacterial activity against methicillin-resistant Staphylococcus epidermidis shhs-E1 with an MIC value of 16.0 μg/mL.

The numerical simulation of propeller cavitation benchmark tests of YUPENG ship model is studied based on OpenFOAM, an open-source CFD (Computational Fluid Dynamics) platform, and the benchmark tests are introduced as well. The propeller cavitation shape and the hull pressure fluctuation are measured and predicted, respectively. The uncertainty in hull pressure fluctuation measurement is also analyzed, and the analysis showed the uncertainty is below 10%. The cavitation shape and the hull pressure fluctuation predicted show quite good agreement with the observations and measured data, and the influences of the grid resolutions on the unsteady propeller cavitation and the hull pressure fluctuation are investigated as well. The monotonic convergence achieved and the quite small grid uncertainty illustrate the reliability of the numerical simulation methods.

The extensive research on photonic topological insulators has opened up an intriguing way to control electromagnetic (EM) waves. In this work, we numerically demonstrate reconfigurable microwave photon analogues of topological insulator (TIs) in a triangular lattice of elliptical cylinders, according to the theory of topological defects. Multiple topological transitions between the trivial and nontrivial photonic phases can be realized by inhomogeneously changing the ellipse orientation, without altering the lattice structure. Topological protection of the edge states and reconfigurable topological one-way propagation at microwave frequencies, are further verified. Our approach provides a new route towards freely steering light propagations in dielectric photonic crystals (PCs), which has potential applications in the areas of topological signal processing and sensing.

Three new eremophilane sesquiterpenes (1–3) were isolated from the mangrove endophytic fungus Xylaria sp. BL321 together with 07H239-A (4), a known analogue of the new compounds. The structures of these compounds were elucidated by analysis of their MS, 1D and 2D NMR spectroscopic data. Compound 4 showed activation activity on α-glucosidase at 0.15 μM (146%), and then, 4 gradually produced inhibitory activity on α-glucosidase with increasing concentration, and the IC50 value is 6.54 μM.

Nine new angucycline glycosides designated urdamycins N1–N9 (1–9), together with two known congener urdamycins A (10) and B (11), were obtained from a mangrove-derived Streptomyces diastaticus subsp. SCSIO GJ056. The structures of new compounds were elucidated on the basis of extensive spectroscopic data analysis. The absolute configurations of 6–9 were assigned by electronic circular dichroism calculation method. Urdamycins N7 (7) and N8 (8) represent the first naturally occurring (5R, 6R)-angucycline glycosides, which are diastereomers of urdamycins N6 (6) and N9 (9), respectively.