Comparison of breast-conserving surgery and mastectomy in early breast cancer using observational data revisited: a propensity score-matched analysis

Recent observational studies showed that breast-conserving surgery (BCS) resulted in superior survival compared to mastectomy in breast cancer patients. This study compared the clinical outcomes of BCS and mastectomy using propensity score (PS) matching analysis, which had advantages over conventional methods in reducing bias. Nonmetastatic breast cancer patients who underwent BCS and mastectomy were matched 1:1 based on their PS. We used the Kaplan-Meier method and Cox-regression model to estimate the treatment effects. A total of 2,866 patients with a median follow-up time of 67 months were included in the original study population. Although the mastectomy cohort (N=1,219) had more advanced disease compared to the BCS cohort (N=1,647), LRFS was similar between the two groups (93.8% vs. 92.4%, P>0.05). BCS (vs. mastectomy) was associated with improved DFS (73.8% vs. 58.7%, P<0.01) and CSS (91% vs. 78.2%, P<0.01) in the original population. In the PS-matched population (N=1,668), clinicopathological features were equally distributed between the two cohorts. BCS (vs. mastectomy) was not associated with improved DFS (70.7% vs. 66.9%, P>0.05) or CSS (87.5% vs. 84.9%, P>0.05). We found that PS methods reduce bias when estimating treatment effects using observational data. BCS and mastectomy show equivalent outcomes in nonmetastatic breast cancer patients.     

Receptor-like protein kinases:Key regulators controlling root hair development in Arabidopsis thaliana

Root hairs are tubular outgrowths specifically differentiated from epidermal cells in a differentiation zone. The formation of root hairs greatly increases the surface area of a root and maximizes its ability to absorb water and inorganic nutrients essential for plant growth and development. Root hair development is strictly regulated by intracellular and intercellular signal communications. Cell surface-localized receptor-like protein kinases(RLKs) have been shown to be important components in these cellular processes. In this review,the functions of a number of key RLKs in regulating Arabidopsis root hair development are discussed, especially those involved in root epidermal cell fate determination and root hair tip growth.     

Anchoring PdCu Amorphous Nanocluster on Graphene for Electrochemical Reduction of N2 to NH3 under Ambient Conditions in Aqueous Solution

As an alternative approach for N₂ fixation under milder conditions, electrocatalytic nitrogen reduction reaction (NRR) represents a very attractive strategy for sustainable development and N₂ cycle to store and utilize energy from renewable sources. However, the research on NRR electrocatalysts still mainly focuses on noble metals, while, high costs and limited resources greatly restrict their large‐scale applications. Herein, as a proof‐of‐concept experiment, taking PdCu amorphous nanocluster anchored on reduced graphene oxide (rGO) as NRR catalysts, the optimum Pd_0.2Cu_0.8/rGO composite presents a synergistic effect and shows superior electrocatalytic performance toward NRR under ambient conditions (yield: 2.80 µg h^?1 mg_cat.^?1 at ?0.2 V vs reversible hydrogen electrode), which is much higher than that of monometallic, especially noble metal, counterparts. The superior catalytic performance of alloy catalysts with low noble metal loading would strongly spur interest toward more researches on NRR catalysts in the future.     

Enhancing Optical,Electronic, Crystalline,and Morphological Properties of Cesium Lead Halide by Mn Substitution for High‐Stability All‐Inorganic Perovskite Solar Cells with Carbon Electrodes

In this work all‐inorganic perovskite CsPbIBr₂ are doped with Mn to compensate their shortcomings in band structure for the application of perovskite solar cells (PSCs). The novel Mn‐doped all‐inorganic perovskites, CsPb_1?xMn_xI_1+2xBr_2?2x, are prepared in ambient atmosphere. As the concentration of Mn²⁺ ions increases, the bandgaps of CsPb_1?xMn_xI_1+2xBr_2?2x decrease from 1.89 to 1.75 eV. Additionally, when the concentration of Mn dopants is appropriate, this novel Mn‐doped all‐inorganic perovskite film shows better crystallinity and morphology than its undoped counterpart. These advantages alleviate the energy loss in hole transfer and facilitate the charge‐transfer in perovskites, therefore, PSCs based on these novel CsPb_1?xMn_xI_1+2xBr_2?2x perovskite films display better photovoltaic performance than the undoped CsPbIBr₂ perovskite films. The reference CsPbIBr₂ cell reaches a power conversion efficiency (PCE) of 6.14%, comparable with the previous reports. The CsPb_1?xMn_xI_1+2xBr_2?2x cells reach the highest PCE of 7.36% (when x = 0.005), an increase of 19.9% in PCE. Furthermore, the encapsulated CsPb_0.995Mn_0.005I_1.01Br_1.99 cells exhibit good stability in ambient atmosphere. The storage stability measurements on the encapsulated PSCs reveal that PCE is dropped by only 8% of the initial value after >300 h in ambient. Such improved efficiency and stability are achieved using low‐cost carbon electrodes (without expensive hole transport materials and Au electrodes).     

Complete Dehydrogenation of N2H4BH3 over Noble‐Metal‐Free Ni0.5Fe0.5–CeOx/MIL‐101 with High Activity and 100% H2 Selectivity

Efficient and selective dehydrogenation of hydrazine borane (HB), a novel hydrogen storage material with very high hydrogen content (HB, 15.4 wt%), is a key challenge for a fuel‐cell‐based hydrogen economy. However, even using the noble metal catalysts for HB decomposition, the activities are still far from satisfying, to say nothing of non‐noble‐metal‐containing catalysts. In response, as a proof‐of‐concept experiment, herein, noble‐metal‐free NiFe–CeO_x nanoparticles are successfully immobilized on an MIL‐101 support without surfactant by a simple liquid impregnation method. Unexpectedly, the resultant Ni_0.5Fe_0.5–CeO_x/MIL‐101 catalyst shows good performance, including 100% H₂ selectivity, 100% conversion, and record catalytic activity (351.3 h^?1) for hydrogen generation at mild temperature, which is even better than most of the noble metal heterogeneous catalysts and might be attributed to the good dispersion and uniform particle size of the Ni_0.5Fe_0.5–CeO_x nanoparticles due to steric restrictions effect of the MIL‐101 support. Additionally, extending MIL‐101 to some other important kinds of metal–organic framework (MOF) structures, the resultant NiFe–CeO_x/MOF catalysts all show good catalytic activity toward HB decomposition, showing the universality of the MOF supported NiFe–CeO_x catalysts.     

Toward High Efficiency Polymer Solar Cells: Rearranging the Backbone Units into a Readily Accessible Random Tetrapolymer

Two donor–acceptor (D–A) conjugated polymers composed of the same ratio of 5‐fluorobenzothiadiazole and thiophene subunits are synthesized through different routes, providing a precisely regioregular ( 2TRR ) and a random ( 2TRA ) polymer structures. Detailed structural analyses indicate that the backbone of regioregular 2TRR has only one donor segment of bithiophene, while the backbone of random 2TRA consists of three different donor segments: thiophene, bithiophene, and terthiophene (in a ratio of 0.16:0.68:0.16). Synergetic contributions from these segments allow the “tetrapolymer” 2TRA to achieve more favorable film morphology and a higher hole‐mobility relative to 2TRR . Consequently, the random polymer 2TRA achieves a substantially higher power conversion efficiency (8.8%) than the regioregular polymer 2TRR (5.1%). Notably, the “tetrapolymer” 2TRA is readily synthesized from two monomers, rather than through complex conventional preparation required for similar multipolymers. These findings provide a novel route toward the design and synthesis of multipolymeric materials and demonstrate their potential advantages in high‐performance organic electronic applications.     

Host‐induced gene silencing of an important pathogenicity factor PsCPK1 in Puccinia striiformis f. sp. tritici enhances resistance of wheat to stripe rust

Rust fungi are devastating plant pathogens and cause a large economic impact on wheat production worldwide. To overcome this rapid loss of resistance in varieties, we generated stable transgenic wheat plants expressing short interfering RNAs (siRNAs) targeting potentially vital genes of Puccinia striiformis f. sp. tritici (Pst). Protein kinase A (PKA) has been proved to play important roles in regulating the virulence of phytopathogenic fungi. PsCPK1, a PKA catalytic subunit gene from Pst, is highly induced at the early infection stage of Pst. The instantaneous silencing of PsCPK1 by barley stripe mosaic virus (BSMV)‐mediated host‐induced gene silencing (HIGS) results in a significant reduction in the length of infection hyphae and disease phenotype. These results indicate that PsCPK1 is an important pathogenicity factor by regulating Pst growth and development. Two transgenic lines expressing the RNA interference (RNAi) construct in a normally susceptible wheat cultivar displayed high levels of stable and consistent resistance to Pst throughout the T₃ to T₄ generations. The presence of the interfering RNAs in transgenic wheat plants was confirmed by northern blotting, and these RNAs were found to efficiently down‐regulate PsCPK1 expression in wheat. This study addresses important aspects for the development of fungal‐derived resistance through the expression of silencing constructs in host plants as a powerful strategy to control cereal rust diseases.     

A dual role for proline iminopeptidase in the regulation of bacterial motility and host immunity

During plant–pathogen interactions, pathogenic bacteria have evolved multiple strategies to cope with the sophisticated defence systems of host plants. Proline iminopeptidase (PIP) is essential to Xanthomonas campestris pv. campestris (Xcc) virulence, and is conserved in many plant‐associated bacteria, but its pathogenic mechanism remains unclear. In this study, we found that disruption of pip in Xcc enhanced its flagella‐mediated bacterial motility by decreasing intracellular bis‐(3′,5′)‐cyclic dimeric guanosine monophosphate (c‐di‐GMP) levels, whereas overexpression of pip in Xcc restricted its bacterial motility by elevating c‐di‐GMP levels. We also found that PIP is a type III secretion system‐dependent effector capable of eliciting a hypersensitive response in non‐host, but not host plants. When we transformed pip into the host plant Arabidopsis, higher bacterial titres were observed in pip‐overexpressing plants relative to wild‐type plants after Xcc inoculation. The repressive function of PIP on plant immunity was dependent on PIP's enzymatic activity and acted through interference with the salicylic acid (SA) biosynthetic and regulatory genes. Thus, PIP simultaneously regulates two distinct regulatory networks during plant–microbe interactions, i.e. it affects intracellular c‐di‐GMP levels to coordinate bacterial behaviour, such as motility, and functions as a type III effector translocated into plant cells to suppress plant immunity. Both processes provide bacteria with the regulatory potential to rapidly adapt to complex environments, to utilize limited resources for growth and survival in a cost‐efficient manner and to improve the chances of bacterial survival by helping pathogens to inhabit the internal tissues of host plants.     

Germline silencing of UASt depends on the piRNA pathway

正The success of the fruit fly Drosophila melanogaster as a model organism is heavily attributed to the expansive range and multitude of genetic and molecular tools available to modify gene expression at will.The Gal4/UAS binary system is one of the most important and widely used genetic tools in Drosophila designed for targeted gene expression(Brand and Perrimon,1993),which allows ectopic expression of any gene(or transgene)in specific tissues,independent of their native regulators.