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Background: Radiotherapy after breast-conserving surgery (BCS) is not always necessary in older women staged T1N0M0 with low-risk invasive breast cancer, but few studies have concluded the detailed tumor size as a reference for avoiding radiotherapy. The study was conducted to explore and identify the optimal cutoff tumor size. Methods: The study population was from the Surveillance, Epidemiology, and End Results (SEER) database in 2010–2016. Propensity score matching was used to balance the confounders between groups. Predictors associated with survival were analyzed by Kaplan–Meier, X-tile, Cox proportional hazards model and competing risk model. Results: A total of 52049 women and 3846 deaths were included in the cohort with a median follow-up of 34 months. Based on the cutoff value determined by X-tile analysis, the study population were divided into small tumor group (≤14 mm in diameter) and large tumor group (>14 mm in diameter). Small tumors and radiotherapy were correlated with better breast cancer-specific survival (BCSS). In subgroup analysis, the absolute benefit of BCSS in 6 years attributed to radiotherapy was only 0.90% (RT vs. non- RT:98.77% vs. 97.87%) for patients with small tumors but up to 3.33% (RT vs. non- RT:97.10% vs. 93.77%) for those with large tumors. Conclusion: Small tumors and adjuvant radiotherapy were associated with improved long-term prognosis, and 14 mm in diameter was the cutoff tumor size of omitting radiotherapy for patients aged 65 or older with T1N0M0 stage, ER+ and HER2-breast carcinoma after BCS.

Background: The role of surgery and surgery type in de novo stage IV breast cancer (BC) is unclear.Methods: We carried out a retrospective cohort study that included the data of 4,108 individuals with de novo stage IV BC abstracted from SEER (Surveillance, Epidemiology, and End Results) data resource from 2010 to 2015. The patients were stratified into the non-surgery group, breast-conserving (BCS) surgery group, and mastectomy group. Inverse probability propensity score weighting (IPTW) was then used to balance clinicopathologic factors. Overall survival (OS), as well as the breast cancer-specific survival (BCSS), was assessed in the three groups using Kaplan–Meier analysis and COX model. Subgroups were stratified by metastatic sites for analysis.Results: Of the 4,108 patients, 48.5% received surgery and were stratified into the BCS group (574 cases) and mastectomy group (1,419 cases). After IPTW balance demographic and clinicopathologic factors, BCS and mastectomy groups had better OS (BCS group: HR, 0.61; 95% CI: 0.49–0.75; mastectomy group: HR, 0.7; 95% CI: 0.63–0.79) and BCSS (BCS group: HR, 0.6; 95% CI, 0.47–0.75; mastectomy group: HR, 0.71; 95% CI, 0.63–0.81) than the non-therapy group. Subgroup analyses revealed that BCS, rather than mastectomy, was linked to better OS (HR, 0.66; 95% CI: 0.48–0.91) and BCSS (HR, 0.63; 95% CI: 0.45–0.89) for patients with bone-only metastasis. For patients with viscera metastasis or bone+viscera metastases, BCS achieved similar OS (viscera metastasis: HR, 1.05; 95% CI: 0.74–1.48; bone+viscera metastases: HR, 1.01; 95% CI: 0.64–1.61) and BCSS (viscera metastasis: HR, 0.94; 95% CI: 0.64–1.38; bone+viscera metastases: HR, 1.06; 95% CI: 0.66–1.73) in contrast with mastectomy.Conclusions: Local surgery for patients with distant metastasis (DS) exhibited a remarkable survival advantage in contrast with non-operative management. BCS may have more survival benefits for patients with de novo stage IV BC with bone-only metastasis than other metastatic sites. Decisions on de novo stage IV BC primary surgery should be tailored to the metastatic pattern.

The effect of Sr2+ ions on the microstructure and high frequency properties of 2.5 wt% Bi2O3 added to Co(2)Z hexaferrites (3Ba(1-x)SrxO•2CoO•12Fe2O3, x = 0.0, 0.2, 0.4 and 0.6) synthesised using the solid-state reaction method was investigated. Experimental results indicate that the dielectric properties were markedly enhanced with the increase in the content of Sr2+ ions, thereby increasing the miniaturisation factor, which enables a size reduction in a long frequency range. Slight changes to saturation magnetisation (Ms) and coercivity (Hc) were observed, i.e., the saturation magnetisation (Ms) decreased from 39.99 to 38.11 emu/g, and coercivity (Hc) increased from 59.05 to 65.21 Oe when x increased from 0.0 to 0.6. Meanwhile, ε′ increased from approximately 8 to 12, indicating the invariability in μ′. In addition, the processed materials exhibit relatively low magnetic loss and dielectric loss (magnetic loss tanδμ ≈ 0.08 and dielectric loss (tanδε ≈ 0.007)). These results indicate that the substituted CO(2)Z ferrites have excellent potential in high-frequency antenna applications.

BackgroundContralateral prophylactic mastectomy (CPM) in female breast cancer (FBC) is supported by multiple clinical studies and consensus guidelines, but knowledge of preventive contralateral mastectomy in male breast cancer (MaBC) is very limited and its benefits are still controversial.MethodsA retrospective cohort study was enrolled with 4,405 MaBC patients who underwent unilateral mastectomy (UM) or CPM from the Surveillance, Epidemiology, and End Results (SEER) database from 1998 to 2015. A nomogram was built based on the corresponding parameters by competing risks regression to predict the 3-year, 5-year, and 8-year probabilities of BCSD (breast cancer-specific death). C-index and calibration curves were chosen for validation. Net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to estimate the nomogram’s clinical utility.ResultsA total of 4,197 patients received UM and 208 patients received CPM, with 63-months median follow-up. In the competing risks regression, six variables (surgery, marital status, T-stage, N-stage, histology, tumor grade) were significantly associated with BCSD. Based on these independent prognosis factors, a nomogram model was constructed. The C-index 0.75 (95%CI: 0.73-0.77) in the training cohort and 0.73 (95%CI: 0.71-0.74) in the internal validation group suggested robustness of the model. In addition, the calibration curves exhibited favorably. The NRI values (training cohort: 0.54 for 3-year, 0.55 for 5-year, and 0.49 for 8-year BCSD prediction; validation cohort: 0.51 for 3-year, 0.45 for 5-year, and 0.33 for 8-year BCSD prediction) and IDI values (training cohort: 0.02 for 3-year, 0.03 for 5-year, and 0.04 for 8-year BCSD prediction; validation cohort: 0.02 for 3-year, 0.04 for 5-year, and 0.04 for 8-year BCSD prediction) indicated that the model performed better than the AJCC criteria-based tumor staging alone.ConclusionsThe administration of CPM was associated with the decrease in risk of BCSD in patients with MaBC. The nomogram could provide a precise and personalized prediction of the cumulative risk in patients with MaBC after CPM.

PurposeDue to the rarity of metaplastic breast carcinoma (MpBC), no randomized trials have investigated the role of combined chemotherapy and radiotherapy (CCRP) in this condition. We aimed to explore and identify the effectiveness of CCRP in patients with regional lymph node metastasis (N+) non-metastatic MpBC.Materials and MethodsData were obtained from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program database. We assessed the effects of CCRP on overall survival (OS), breast cancer-specific survival (BCSS), and breast cancer-specific death (BCSD) using Kaplan-Meier analysis, competing risk model analysis, and competing risk regression mode analysis.ResultsA total of 707 women and 361 death cases were included in the unmatched cohort, of which 76.45% (276/361) were BCSD, and 23.55% (85/361) were non-breast cancer-specific deaths (non-BCSD). Both the ChemT and CCRP groups had better OS (ChemT group: HR: 0.59, 95% CI: 0.45–0.78, P

Six new aromatic acids (1–6) and three new leucine derivatives containing an unusual oxime moiety (7–9) were isolated and identified from the deep-sea-derived actinomycetes strain Streptomyces chumphonensis SCSIO15079, together with two known compounds (10–11). The structures of 1–9 including absolute configurations were determined by detailed NMR, MS, and experimental and calculated electronic circular dichroism spectroscopic analyses. Compounds 1–9 were evaluated for their antimicrobial and cytotoxicity activities, as well as their effects on intracellular lipid accumulation in HepG2 cells. Compounds 3 and 4, with the most potent inhibitory activity on intracellular lipid accumulation at 10 μM, were revealed with potential antihyperlipidemic effects, although the mechanism needs to be further studied.

IntroductionKnowledge of the association between isolated tumor cells (ITCs) in breast cancer patients and the outcome is very limited. We aimed to determine the prognostic value of axillary lymph node ITCs for T1N0M0 female breast cancer (FBC) patients.MethodsData for T1N0M0 FBC patients staged ITCs negative [pN0(i−)] and positive [pN0(i+)] were extracted from the Surveillance, Epidemiology, and End Results database from 2004 to 2015. Prognostic predictors were identified by Kaplan–Meier analysis, competing risk model, and Fine–Gray multivariable regression model.ResultsA total of 94,599 subjects were included, 88,632 of whom were staged at pN0(i−) and 5,967 were pN0(i+). Patients staged pN0(i+) had worse breast cancer-specific survival (BCSS) [hazard ratio (HR): 1.298, 95% CI = 1.069–1.576, P = 0.003] and higher breast cancer-specific death (BCSD) rate (Gray’s test, P = 0.002) than pN0(i−) group. In the Fine–Gray multivariable regression analysis, the pN0(i+) group had higher BCSD rate (HR: 1.321, 95% CI = 1.109–1.575, P = 0.002) than pN0(i−) group. In subgroup analyses, no significant difference in BCSD was shown between the chemotherapy and non-chemotherapy subgroup (Gray’s test, P = 0.069) or radiotherapy and non-radiotherapy subgroup (Gray’s test, P = 0.096).ConclusionITC was independently related to the increase of the BCSD rate and could be identified as a reliable survival predictor for T1N0M0 FBC patients.

A growing body of evidence indicates that glycosylated natural products have become vital platforms for the development of many existing first-line drugs. This review covers 205 new glycosides over the last 22 years (1997–2018), from marine microbes, including bacteria, cyanobacteria, and fungi. Herein, we discuss the structures and biological activities of these compounds, as well as the details of their source organisms.

The mangrove-sediment-derived actinomycete strain Streptomyces psammoticus SCSIO NS126 was found to have productive piericidin metabolites featuring anti-renal cell carcinoma activities. In this study, in order to explore more diverse piericidin derivatives, and therefore to discover superior anti-tumor lead compounds, the NS126 strain was further fermented at a 300-L scale under optimized fermentation conditions. As a result, eight new minor piericidin derivatives (piericidins L-R (1–7) and 11-demethyl-glucopiericidin A (8)) were obtained, along with glucopiericidin B (9). The new structures including absolute configurations were determined by spectroscopic methods coupled with experimental and calculated electronic circular dichroism. We also proposed plausible biosynthetic pathways for these unusual post-modified piericidins. Compounds 1 and 6 showed selective cytotoxic activities against OS-RC-2 cells, and 2–5 exhibited potent cytotoxicity against HL-60 cells, with IC50 values lower than 0.1 μM. The new piericidin glycoside 8 was cytotoxic against ACHN, HL-60 and K562, with IC50 values of 2.3, 1.3 and 5.5 μM, respectively. The ability to arrest the cell cycle and cell apoptosis effects induced by 1 and 6 in OS-RC-2 cells, 2 in HL-60 cells, and 8 in ACHN cells were then further investigated. This study enriched the structural diversity of piericidin derivatives and confirmed that piericidins deserve further investigations as promising anti-tumor agents.

A pair of novel lipopeptide epimers, sinulariapeptides A (1) and B (2), and a new phthalide glycerol ether (3) were isolated from the marine algal-associated fungus Cochliobolus lunatus SCSIO41401, together with three known chromanone derivates (4–6). The structures of the new compounds, including the absolute configurations, were determined by comprehensive spectroscopic methods, experimental and calculated electronic circular dichroism (ECD), and Mo2 (OAc)4-induced ECD methods. The new compounds 1–3 showed moderate inhibitory activity against acetylcholinesterase (AChE), with IC50 values of 1.3–2.5 μM, and an in silico molecular docking study was also performed.

We theoretically study the extreme ultraviolet (XUV) photoemission of the asymmetric molecular ion HeH^{2+} beyond the dipole approximation. Based on the double-slit interference of the photoelectron emitted from two atomic cores, we propose a scheme to obtain the XUV photoemission time delays originated from different physical mechanisms. In our study, two types of sub-attosecond photoemission time delays are identified and extracted from the observable photoelectron momentum distributions. One is the so-called birth time delay, originated from the travel time of the photon across the molecule, and the other is the escaping time delay of the photoelectron from two different cores. The present study shows the observable evidence demonstrating that in single-photon ionization, it takes more time for the photoelectron escaping from the helium nucleus than that from the proton.

Coupled nuclear and electronic dynamics within a molecule are key to understanding a broad range of fundamental physical and chemical processes. Although probing the coupled vibrational and electronic dynamics was demonstrated, it has so far been challenging to observe the coupling interactions between the rotational and electronic degrees of freedom. Here, we report the first observation of Coriolis coupling, a coupling interaction between nuclear rotational angular momentum and electronic axial angular momentum, during laser-induced molecular fragmentation by tracing the electronic structure of a dissociating [Formula: see text] molecule. We observe that the electron density changes its shape from that of a molecular σ orbital to a nearly isotropic shape as the internuclear distance goes up to ∼20 Å, which results from the transition between nearly degenerate electronic states associated with different rotational angular momenta. Our experiment demonstrates that the breaking of a chemical bond does not occur suddenly during molecular dissociation. Instead, it lasts for a long time of several hundred femtoseconds due to the Coriolis coupling interaction. Our experiment can be extended to complicated molecules, holding the potential of revealing yet unobserved electron–nuclear coupling interactions during ultrafast processes.

Two new α-methoxy-γ-pyrone analogs, 2-methoxy-3-methyl-5,6-diethyl-γ-pyrone (2) and 2-methoxy-3,5-dimethyl-6-propyl-γpyrone (3), together with 2-methoxy-3,5-dimethyl-6-ethyl-γ-pyrone (1), firstly isolated from natural sources, were obtained from the EtOAc-solube extract of the mangrove sediment-derived actinomycete strain Streptomyces psammoticus SCSIO NS126, under the optimized fermentation conditions. Their structures were elucidated by detailed spectroscopic analysis and by comparison of their spectroscopic data with those reported in the literature. Those α-methoxy-γ-pyrones were evaluated for their acetylcholinesterase inhibitory activity; however, none of them exhibited obvious activity. Moreover, their biosynthetic relationship with piericidins was also discussed. [ABSTRACT FROM AUTHOR]

It remains a challenge to fabricate metal catalysts with interfacial active sites distributed on the whole two-dimensional (2D) surface of metal nanoparticles. Here the authors demonstrate that the overgrowth of atomic-thick porous Cu2O on Pd readily creates an unprecedented 2D catalytically active metal-support interface with significantly enhanced catalysis toward the semi-hydrogenation of alkynes.

Precious metal catalysts are the cornerstone of many industrial processes. Replacing precious metal catalysts with earth-abundant metals is one of key challenges for the green and sustainable development of chemical industry. We report in this work a surprisingly effective strategy toward the development of cost-effective, air-stable, and efficient Ni catalysts by simple surface modification with thiols. The as-prepared catalysts exhibit unprecedentedly high activity and selectivity in the reductive amination of aldehydes/ketones. The thiol modification can not only prevent the deep oxidation of Ni surface to endow the catalyst with long shelf life in air but can also allow the reductive amination to proceed via a non-contact mechanism to selectively produce primary amines. The catalytic performance is far superior to that of precious and non-precious metal catalysts reported in the literature. The wide application scope and high catalytic performance of the developed Ni catalysts make them highly promising for the low-cost, green production of high-value amines in chemical industry.

We theoretically investigated frustrated tunneling ionization (FTI) driven by spatially inhomogeneous strong laser fields induced by surface plasmon resonance within a bow-tie metal nanostructure. The results show that the FTI probability and the principal quantum number distribution exhibit similar oscillatory behavior as a function of the pulse duration. Our analysis reveals that the periodic defocusing and refocusing of the electron spatial distribution due to the inhomogeneous laser field is responsible for the oscillatory structures. In addition, the initial tunneling coordinates and the angular momentum distributions of the FTI events and theirs pulse duration dependence are also explored. Moreover, our results show that the frequency of the oscillatory structures depends sensitively on the electron quiver amplitude and the inhomogeneity strength. Thus, the electron quiver amplitude and the size of the gap between bow-tie nanostructure are useful and efficient knobs for controlling the yield and properties of exited Rydberg states.

The annual cumulative quantity of high and medium alloy steel scrap has exceeded 10 million tons. Using the traditional smelting process involving electric arc refining in a smelting furnace for these scraps causes high percentages of alloy losses, which decreases the value of the alloy steel scrap and poses environmental threats. Existing studies have rarely focused on separate smelting of the scrap and oxidation behaviors of the alloying elements. Therefore, this study proposes an induction melting and electroslag remelting scheme to process the scrap. Based on this scheme, the effects of the temperature, oxygen content, and element contents on the recovery percentages of the alloying elements were investigated using pilot experiment and thermodynamic analysis. The experimental results showed that the alloying elements (tungsten, chromium, nickel, molybdenum, and vanadium) exhibited recovery percentages of 97.36%, 94.62%, 97.63%, 95.09%, and 89.49%, respectively; furthermore, the impurity content did not increase during smelting. The thermodynamic analysis indicated that an increase in carbon content improved the oxidation resistance of the alloying elements except for nickel, whereas the increases in the contents of oxygen and alloying elements increase their oxidation. Steam partial pressure and air suction dramatically increase the concentrations of nitrogen, hydrogen and oxygen. This scheme is an alternative for smelting medium and high alloy steel scrap, and the thermodynamic analysis provides a theoretical understanding of the oxidation behaviors of the alloying elements in the steel scrap and the control of impurity.

Size effect plays a crucial role in catalytic hydrogenation. The highly dispersed ultrasmall clusters with a limited number of metal atoms are one candidate of the next generation catalysts that bridge the single-atom metal catalysts and metal nanoparticles. However, for the unfavorable electronic property and their interaction with the substrates, they usually exhibit sluggish activity. Taking advantage of the small size, their catalytic property would be mediated by surface binding species. The combination of metal cluster coordination chemistry brings new opportunity. CO poisoning is notorious for Pt group metal catalysts as the strong adsorption of CO would block the active centers. In this work, we will demonstrate that CO could serve as a promoter for the catalytic hydrogenation when ultrasmall Pd clusters are employed. By means of DFT calculations, we show that Pdn n=2‐147 clusters display sluggish activity for hydrogenation due to the too strong binding of hydrogen atom and reaction intermediates thereon, whereas introducing CO would reduce the binding energies of vicinal sites, thus enhancing the hydrogenation reaction. Experimentally, supported Pd2CO catalysts are fabricated by depositing preestablished [Pd2(μ-CO)2Cl4]2- clusters on oxides and demonstrated as an outstanding catalyst for the hydrogenation of styrene. The promoting effect of CO is further verified experimentally by removing and reintroducing a proper amount of CO on the Pd cluster catalysts.

To reduce energy and resource consumption, high-strength hot-rolled rebars with yield strengths of ≥400 MPa (HRB500) and ≥500 MPa (HRB600) have been designed and produced in recent years. Optimizing the microstructure in the steel to improve strength necessitates determining the kinetics of the phase transition of austenite to polygonal ferrite. Therefore, in the study, the effect of temperature and holding time on the volume fraction of ferrite is investigated in HRB500 and HRB600 steels. Experimental results show that the ferrite percentage initially increases with an increase in temperature and then decreases as the temperature increases from 600 to 730 °C. The optimum temperature range is 680–700 °C for HRB500 steel and 650–680 °C for HRB600 steel. Based on the Johnson–Mehl–Avrami equation, phase transition kinetic models are established. Model predictions are consistent with the validation data. Thus, this study establishes a reference for studying ferrite formation during cooling.

Thus far, the role of the carrier-envelope phase (CEP) of a light pulse has generally been demonstrated in the few-cycle (sub-10 fs) regime. Here, by simulating the molecular dynamics of H ^+ _2 and D ^+ _2 , we report that the electron localization of H ^+ _2 and D ^+ _2 exhibits unexpectedly strong CEP dependence in the multicycle regime. Our results also demonstrate that the electron localization asymmetry in the multicycle regime (15–20 fs) is higher than that in the single-cycle (4 fs) pulse. This counterintuitive phenomenon is discussed by monitoring the motions of both nuclear and electronic wavepackets.