Vegetation-fire feedbacks increase subtropical wildfire risk in scrubland and reduce it in forests

Climate dictates wildfire activity around the world. But East and Southeast Asia are an apparent exception as fire-activity variation there is unrelated to climatic variables. In subtropical China, fire activity decreased by 80% between 2003 and 2020 amid increased fire risks globally. Here, we assessed the fire regime, vegetation structure, fuel flammability and their interactions across subtropical Hubei, China. We show that tree basal area (TBA) and fuel flammability explained 60% of fire-frequency variance. Fire frequency and fuel flammability, in turn, explained 90% of TBA variance. These results reveal a novel system of scrubland-forest stabilized by vegetation-fire feedbacks. Frequent fires promote the persistence of derelict scrubland through positive vegetation-fire feedbacks; in forest, vegetation-fire feedbacks are negative and suppress fire. Thus, we attribute the decrease in wildfire activity to reforestation programs that concurrently increase forest coverage and foster negative vegetation-fire feedbacks that suppress wildfire.

Chemoproteomic mapping of the glycolytic targetome in cancer cells

Hyperactivated glycolysis is a metabolic hallmark of most cancer cells. Although sporadic information has revealed that glycolytic metabolites possess nonmetabolic functions as signaling molecules, how these metabolites interact with and functionally regulate their binding targets remains largely elusive. Here, we introduce a target-responsive accessibility profiling (TRAP) approach that measures changes in ligand binding-induced accessibility for target identification by globally labeling reactive proteinaceous lysines. With TRAP, we mapped 913 responsive target candidates and 2,487 interactions for 10 major glycolytic metabolites in a model cancer cell line. The wide targetome depicted by TRAP unveils diverse regulatory modalities of glycolytic metabolites, and these modalities involve direct perturbation of enzymes in carbohydrate metabolism, intervention of an orphan transcriptional protein's activity and modulation of targetome-level acetylation. These results further our knowledge of how glycolysis orchestrates signaling pathways in cancer cells to support their survival, and inspire exploitation of the glycolytic targetome for cancer therapy.

Biomimetic Guided Bi2WO6/Bi2O3 Vertical Heterojunction with Controllable Microstructure for Efficient Photocatalysis

To bridge the technical gap of heterojunction induction control in conventional semiconductor photocatalysts, a method of regulating the growth of heterojunctions utilizing biomimetic structures was designed to prepare a series of Bi2WO6/Bi2O3 vertical heterojunction nanocomposites for the disposal of environmentally hazardous tetracycline wastewater difficult to degrade by conventional microbial techniques. Porous Bi2O3 precursors with high-energy crystalline (110) dominant growth were produced using the sunflower straw bio-template technique (SSBT). Bi2WO6 with a (131) plane grew preferentially into 2.8 to 4 nm pieces on the (110) plane of Bi2O3, causing a significant density reduction between Bi2WO6 pieces and a dimensional decrease in the agglomerated Bi2WO6 spheres from 3 μm to 700 nm since Bi2WO6 grew on the structure of the biomimetic Bi2O3. The optimal 1:8 Bi2WO6/Bi2O3 coupling catalyst was obtained via adapting the ratio of the two semiconductors, and the coupling ratio of 1:8 minimized the adverse effects of the overgrowth of Bi2WO6 on degradation performance by securing the quantity of vertical heterojunctions. The material degradation reaction energy barrier and bandgap were significantly reduced by the presence of a large number of vertical heterojunction structures, resulting in a material with lower impedance and higher electron–hole separation efficiency; thus, the degradation efficiency of 1:8 Bi2WO6/Bi2O3 for tetracycline hydrochloride reached 99% within 60 min. In conclusion, this study not only successfully synthesized a novel photocatalyst with potential applications in water pollution remediation but also introduced a pioneering approach for semiconductor-driven synthesis.

From stress to responses: aluminium-induced signalling in the root apex

Aluminium (Al) toxicity is one of the major constraints for crop growth and productivity in most of the acid soils worldwide. The primary lesion of Al toxicity is the rapid inhibition of root elongation. The root apex, especially the transition zone (TZ), has been identified as the major site of Al accumulation and injury. The signalling, in particular through phytohormones in the root apex TZ in response to Al stress, has been reported to play crucial roles in the regulation of Al-induced root growth inhibition. The binding of Al in the root apoplast is the initial event leading to inhibition of root elongation. Much progress has been made during recent years in understanding the molecular functions of cell wall modification and Al resistance-related genes in Al resistance or toxicity, and several signals including phytohormones, Ca2+, etc. have been reported to be involved in these processes. Here we summarize the recent advances in the understanding of Al-induced signalling and regulatory networks in the root apex involved in the regulation of Al-induced inhibition of root growth and Al toxicity/resistance. This knowledge provides novel insights into how Al-induced signals are recognized by root apical cells, transmitted from the apoplast to symplast, and finally initiate the defence system against Al. We conclude that the apoplast plays a decisive role in sensing and transmitting the Al-induced signals into the symplast, further stimulating a series of cellular responses (e.g. exudation of organic acid anions from roots) to adapt to the stress. We expect to stimulate new research by focusing on the signalling events in the root apex in response to Al stress, particularly taking into consideration the signal transduction between the meristem zone, TZ, and elongation zone and the apoplast and symplast.

Effectiveness and safety of pembrolizumab for patients with advanced non-small cell lung cancer in real-world studies and randomized controlled trials: A systematic review and meta-analysis

Background

Several randomized controlled trials (RCTs) have confirmed the favorable clinical benefit of pembrolizumab in advanced non-small cell lung cancer (NSCLC). However, considering the strict inclusion and exclusion criteria in clinical research, there are certain differences between patients in the real-world, it is unclear whether the findings of clinical trials are fully representative of the treatment efficacy in patients who will eventually use it. Therefore, to further comprehensively assess the efficacy and safety of pembrolizumab in NSCLC, we conducted a systematic review and meta-analysis based on the latest RCTs and real-world studies (RWSs).

Methods

We systematically searched PubMed, Embase, The Cochrane Library, The Web of Science, and clinical trials.gov as of December 2021. RCTs and RWSs of patients receiving pembrolizumab monotherapy or in combination with chemotherapy for advanced NSCLC were included.

Results

The meta-analysis ultimately included 11 RCTs and 26 RWSs with a total of 10,695 patients. The primary outcomes of this study were overall survival (OS), progression-free survival (PFS), objective response rate (ORR), serious adverse events (SAEs), the incidence of severe pneumonia reactions, and drug-related mortality. Direct meta-analysis results showed that in RCTs, pembrolizumab in combination with chemotherapy was superior to chemotherapy in terms of OS (HR=0.60, 95%CI:0.50-0.73), PFS (HR=0.47, 95%CI:0.38-0.58) and ORR (OR=3.22, 95%CI:2.57-4.03); pembrolizumab monotherapy was superior to chemotherapy in terms of OS (HR=0.73, 95%CI:0.66-0.80) and ORR (OR=1.90, 95%CI:1.17-3.09), but comparable to chemotherapy in terms of PFS (HR=0.83, 95%CI:0.66-1.04). The ORR values in retrospective single-arm studies were 45% (40%-51%).

Conclusion

In RCTs, pembrolizumab monotherapy or in combination with chemotherapy is more effective and safer than chemotherapy for advanced NSCLC. In RWSs, ECOG PS 0-1 was shown to correlate with PFS and OS for patients with NSCLC.

Structure-Based Design of a Dual-Targeted Covalent Inhibitor Against Papain-like and Main Proteases of SARS-CoV-2

The two proteases, PLpro and Mpro, of SARS-CoV-2 are essential for replication of the virus. Using a structure-based co-pharmacophore screening approach, we developed a novel dual-targeted inhibitor that is equally potent in inhibiting PLpro and Mpro of SARS-CoV-2. The inhibitor contains a novel warhead, which can form a covalent bond with the catalytic cysteine residue of either enzyme. The maximum rate of the covalent inactivation is comparable to that of the most potent inhibitors reported for the viral proteases and covalent inhibitor drugs currently in clinical use. The covalent inhibition appears to be very specific for the viral proteases. The inhibitor has a potent antiviral activity against SARS-CoV-2 and is also well tolerated by mice and rats in toxicity studies. These results suggest that the inhibitor is a promising lead for development of drugs for treatment of COVID-19.

Targeting cathepsin B by cycloastragenol enhances antitumor immunity of CD8 T cells via inhibiting MHC-I degradation

BACKGROUND

The loss of tumor antigens and depletion of CD8 T cells caused by the PD-1/PD-L1 pathway are important factors for tumor immune escape. In recent years, there has been increasing research on traditional Chinese medicine in tumor treatment. Cycloastragenol (CAG), an effective active molecule in Astragalus membranaceus, has been found to have antiviral, anti-aging, anti-inflammatory, and other functions. However, its antitumor effect and mechanism are not clear.

METHODS

The antitumor effect of CAG was investigated in MC38 and CT26 mouse transplanted tumor models. The antitumor effect of CAG was further analyzed via single-cell multiomics sequencing. Target responsive accessibility profiling technology was used to find the target protein of CAG. Subsequently, the antitumor mechanism of CAG was explored using confocal microscopy, coimmunoprecipitation and transfection of mutant plasmids. Finally, the combined antitumor effect of CAG and PD-1 antibodies in mice or organoids were investigated.

RESULTS

We found that CAG effectively inhibited tumor growth in vivo. Our single-cell multiomics atlas demonstrated that CAG promoted the presentation of tumor cell-surface antigens and was characterized by the enhanced killing function of CD8⁺ T cells. Mechanistically, CAG bound to its target protein cathepsin B, which then inhibited the lysosomal degradation of major histocompatibility complex I (MHC-I) and promoted the aggregation of MHC-I to the cell membrane, boosting the presentation of the tumor antigen. Meanwhile, the combination of CAG with PD-1 antibody effectively enhanced the tumor killing ability of CD8⁺ T cells in xenograft mice and colorectal cancer organoids.

CONCLUSION

Our data reported for the first time that cathepsin B downregulation confers antitumor immunity and explicates the antitumor mechanism of natural product CAG.

Living Cell-Target Responsive Accessibility Profiling Reveals Silibinin Targeting ACSL4 for Combating Ferroptosis

We report a living cell-target responsive accessibility profiling (LC-TRAP) approach to identify the targetome of silibinin (SIL), a well-established hepatoprotective natural product (NP), in HepG2 cells. Proteins showing accessibility changes, probed by covalent lysine labeling reagents and leveraged by multiplexed quantitative proteomics, following the administration of SIL to the living cells were assigned as potential targets. Among the assigned targetome, ACSL4, an enzyme essential for ferroptosis induction, might be involved in the hepatoprotective effects of SIL and hence was intensively validated. We first demonstrated that SIL protected HepG2 cells from ferroptosis dependent on ACSL4. Then, we used biophysical assays and a SIL-derivatized chemical probe to corroborate that SIL can bind to ACSL4. The ensuing enzymatic assays showed that SIL inhibited ACSL4 enzymatic activity, thereby mitigating the ACSL4-mediated ferroptosis. As such, we revealed that ACSL4 inhibition, using SIL as a model compound, represents a promising hepatoprotective strategy. Further, since TRAP probes the accessibility changes of reactive proteinaceous lysines, it can pinpoint the proximal regions where the ligand engagement may occur. Thus, the LC-TRAP analysis of SIL, the newly discovered ligand of ACSL4, and arachidonic acid (AA), the substrate, intriguingly showed that SIL and AA both affected the conformation of the K536-proximal region of ACSL4, albeit through distinct binding patterns. Collectively, we describe a straightforward LC-TRAP workflow that does not involve ligand-derived probe synthesis and is widely applicable to target discovery of NPs.

Effects of methanol, sodium citrate, and chlorella powder on enhanced anaerobic treatment of coal pyrolysis wastewater

To better promote environment friendly development of the coal chemical industry, this study investigated effects of methanol, sodium citrate, and chlorella powder (a type of microalgae) as co-metabolic substances on enhanced anaerobic treatment of coal pyrolysis wastewater with anaerobic sludge. The anaerobic sludge was loaded into four 2 L anaerobic reactors for co-metabolism enhanced anaerobic experiments. Anaerobic reactor 1 (R1) as control group did not add a co-metabolic substance; anaerobic reactor 2 (R2) added methanol; anaerobic reactor 3 (R3) added sodium citrate; and anaerobic reactor 4 (R4) added chlorella powder. In the blank control group, the removal ratios of total phenol (TPh), quinoline, and indole were only 12.07%, 42.15%, and 50.47%, respectively, indicating that 50 mg/L quinoline, 50 mg/L indole, and 600 mg/L TPh produced strong toxicity inhibition function on the anaerobic microorganism in reactor. When the concentration of methanol, sodium citrate, and chlorella was 400 μg/L, the reactors with co-metabolic substances had better treatment effect on TPh. Among them, the strengthening effects of sodium citrate (TPh removal ratio: 44.87%) and chlorella (47.85%) were better than that of methanol (38.72%) and the control group (10.62%). Additionally, the reactors with co-metabolic substances had higher degradation ratios on quinoline, indole, and chemical oxygen demand (COD). The data of extracellular polymeric substances showed that with the co-metabolic substances, anaerobic microorganisms produced more humic acids by degrading phenols and nitrogen-containing heterocyclic compounds (NHCs). Compared with the control group, the reactors added with sodium citrate and chlorella had larger average particle size of sludge. Thus, sodium citrate and chlorella could improve sludge sedimentation performance by increasing the sludge particle size. The bacterial community structures of reactors were explored and the results showed that Aminicenantes genera incertae sedis, Levinea, Geobacter, Smithella, Brachymonas, and Longilinea were the main functional bacteria in reactor added with chlorella.

Efficacy, safety, and cost-effectiveness analysis of aflibercept in metastatic colorectal cancer: A rapid health technology assessment

Background: Metastatic colorectal cancer (mCRC) imposes a heavy tumor burden worldwide due to limited availability of therapeutic drugs. Aflibercept, a kind of recombinant protein of the anti-vascular endothelial growth factor (VEGF) family, has been approved in clinical application among mCRC patients since 2012. A comprehensive analysis of the efficacy, safety, and cost-effectiveness of aflibercept in mCRC treatment is necessary.

Objective: To evaluate the efficacy, safety, and cost-effectiveness of aflibercept for the treatment of mCRC in order to provide a decision-making reference for the selection of targeted drugs for second-line treatment of mCRC in Hong Kong, Macao, and Taiwan regions of China and the selection of new drugs for medical institutions in these regions.

Methods: A systematic retrieve on databases including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and Weipu, as well as relevant websites and databases of health technology assessment including the National Institute of Health and Clinical Optimization, Centre for Evaluation and Communication at the University of York, and the Canadian Agency for Medicines and Health Technology, was conducted. The literature was screened according to the inclusion and exclusion criteria, and data were extracted and analyzed by two authors, while the quality of the literature was assessed.

Results: Finally, we included two HTA reports, 11 systematic reviews/meta-analyses, and two cost-effectiveness studies in the rapid health technology assessment. For mCRC patients receiving second-line treatment, aflibercept combined with FOLFIRI significantly increased progression-free survival (PFS) and overall survival (OS) and the objective response rate (ORR) also improved, compared with folinic acid + fluorouracil + irinotecan (FOLFIRI). In terms of safety, mCRC patients who received aflibercept combined with FOLFIRI therapy had a higher incidence of grade 3–4 adverse events than those who received FOLFIRI alone, including anti-VEGF–related adverse events (hypertension, hemorrhagic events, and proteinuria) and chemotherapy-related adverse events (diarrhea, weakness, stomatitis, hand-foot syndrome, neutropenia, and thrombocytopenia). In terms of cost-effectiveness, two economic studies conducted in the United Kingdom and Japan, respectively, found that compared with FOLFIRI, aflibercept combined with FOLFIRI had no cost-effectiveness advantage in mCRC patients receiving second-line treatment.

Conclusion: Compared with FOLFIRI treatment, aflibercept combined with FOLFIRI for the second-line treatment of mCRC patients has better efficacy, worse safety, and is not cost-effective. More high-quality clinical studies are required for further exploration of aflibercept’s clinical value. Medical institutions in Hong Kong, Macao, and Taiwan regions of China should be cautious when using or introducing aflibercept plus FOLFIRI as a mCRC treatment.

Cyclic immonium ion of lactyllysine reveals widespread lactylation in the human proteome

Lactylation was initially discovered on human histones. Given its nascence, its occurrence on nonhistone proteins and downstream functional consequences remain elusive. Here we report a cyclic immonium ion of lactyllysine formed during tandem mass spectrometry that enables confident protein lactylation assignment. We validated the sensitivity and specificity of this ion for lactylation through affinity-enriched lactylproteome analysis and large-scale informatic assessment of nonlactylated spectral libraries. With this diagnostic ion-based strategy, we confidently determined new lactylation, unveiling a wide landscape beyond histones from not only the enriched lactylproteome but also existing unenriched human proteome resources. Specifically, by mining the public human Meltome Atlas, we found that lactylation is common on glycolytic enzymes and conserved on ALDOA. We also discovered prevalent lactylation on DHRS7 in the draft of the human tissue proteome. We partially demonstrated the functional importance of lactylation: site-specific engineering of lactylation into ALDOA caused enzyme inhibition, suggesting a lactylation-dependent feedback loop in glycolysis.

China's energy stock market jumps: To what extent does the COVID-19 pandemic play a part?

The price jump behavior may bring tremendous challenges on risk management and asset pricing. This paper uses the BN-S test, the wavelet coherence method, and applies high-frequency data to explore whether and to what extent the COVID-19 pandemic impacts China's energy stock market jumps and its characteristics. The empirical results uncover the significant and heterogeneous interactions between the COVID-19 pandemic and China's energy stock market jumps across market specifications, investment horizons, and China/global pandemic tolls at different time scales. First, the oil stock market jumps were the most correlated with the pandemic, especially during the peak and re-deterioration phases. The pandemic played a positive and leading role in the short term (1-4 days length period) and long term (over 32 days length period). Second, the coal stock market jumps have similar characteristics to those of oil, but mainly show a negative correlation with the pandemic. Third, renewable energy stock market jumps were the least correlated, mainly showing a positive correlation in the short term and a negative correlation in the long term. In addition, the interaction characteristics of systemic co-jumps in different China's energy stock markets are also significant.

A comparative evaluation of chemical composition and antimicrobial activities of essential oils extracted from different chemotypes of Cinnamomum camphora (L.) Presl

The purpose of this study is to determine the chemical composition of the essential oils of Cinnamomum camphora (L.) Presl leaves (CCPL) from 5 different habitats in China by GC-MS, and to evaluate their antimicrobial activities against 3 foodborne pathogens, using a paper disc diffusion method. A total of 30 compounds were identified with a predominance of oxygenated monoterpenes, including linalool (42.65%-96.47%), eucalyptol (39.07%-55.35%) and camphor (26.08%) as well as monoterpene hydrocarbons such as sabinene (6.18%-12.93%) and α-terpineol (8.19%-13.81%). Through cluster analysis, CCPL from 5 different habitats can be well divided into 2 categories. Combining with principal component analysis, the habitats can be better correlated with the chemical constituents of the essential oils. The antimicrobial activities of 5 extracted essential oils against 2 gram-negative bacteria and one gram-positive bacteria were assessed. It showed that the essential oil extracted from the CCPL harvested in Jinxi had the strongest antibacterial property. The results of this study provided basis for resource identification of CCPL and quality difference identification of essential oils. Research on the antibacterial properties of several pathogenic strains has proved its application value as a natural food preservative.

Celastrol targets adenylyl cyclase-associated protein 1 to reduce macrophages-mediated inflammation and ameliorates high fat diet-induced metabolic syndrome in mice

Metabolic syndrome is a clustering of metabolic disorder with unclear molecular mechanism. Increasing studies have found that the pathogenesis and progression of metabolic syndrome are closely related to inflammation. Here, we report celastrol, a traditional Chinese medicine, can improve high fat diet-induced metabolic syndrome through suppressing resistin-induced inflammation. Mechanistically, celastrol binds to adenylyl cyclase associated protein 1 (CAP1) and inhibits the interaction between CAP1 and resistin, which restrains the cyclic adenylate monophosphate (cAMP)-protein kinase A (PKA)-nuclear factor kappa-B (NF-κB) signaling pathway and ameliorates high fat diet-induced murine metabolic syndrome. Knockdown of CAP1 in macrophages abrogated the resistin-mediated inflammatory activity. In contrast, overexpression of CAP1 in macrophages aggravated inflammation. Taken together, our study identifies celastrol, which directly targets CAP1 in macrophages, might be a promising drug candidate for the treatment of inflammatory metabolic diseases, such as metabolic syndrome.

Time-Resolved Acetaldehyde-Based Accessibility Profiling Maps Ligand-Target Interactions

Elucidating ligand-protein interactions is important in understanding the biochemical machinery for given proteins. Previously, formaldehyde (FH)-based labeling has been employed to obtain such structural knowledge, since reactive residues that participate in ligand-target interactions display reduced accessibility to FH-labeling reagents, and thus can be identified by quantitative proteomics. Although being rapid and efficient for probing proteinaceous lysine accessibility, here, we report an acetaldehyde (AcH)-labeling approach that complements with FH for probing ligand-target interactions. AcH labeling examines lysine accessibility at a more moderate reaction speed and hence delivers a cleaner reaction when compared to that of FH. The subsequent application of AcH to label RNase A without and with ligands has assisted to assign lysines involved in ligand-RNase A binding by detecting the time-dependent changes in accessibility profiles. We further employed multiple reaction monitoring (MRM) to quantify these ligand-binding-responsive sites when a variety of potential ligands were queried. We noted that the time-resolved abundance changes of these peptides can sensitively determine the ligand-binding sites and differentiate binding affinities among these ligands, which was confirmed by native mass spectrometry (MS) and molecular docking. Lastly, we demonstrated that the binding sites can be recognized by monitoring the chemical accessibility of these responsive peptides in cell lysates. Together, we believe that the proposed combined use of AcH-based lysine accessibility profiling, native MS, and MRM screening is a powerful toolbox in characterizing ligand-target interactions, mapping topography, and interrogating affinities and holds promise for future applications in a complex cellular environment.

Cost-effectiveness of pembrolizumab plus axitinib as first-line therapy for advanced renal cell carcinoma

Aim: To evaluate the cost-effectiveness of first-line treatments for advanced renal cell carcinoma with pembrolizumab plus axitinib compared with sunitinib from the US payer perspective. Patients & methods: A Markov model was developed for this purpose. The clinical data were obtained from the KEYNOTE-426 trial. Utility values and direct costs related to the treatments were gathered from the published studies. Results: The incremental cost-effectiveness ratios of pembrolizumab plus axitinib versus sunitinib was $249,704 per quality-adjusted life year, which was higher than a willingness-to-pay threshold of $150,000 per quality-adjusted life year. Conclusion: Pembrolizumab plus axitinib was not considered to be cost-effective versus sunitinib as a first-line treatment for patients with advanced renal cell carcinoma from the US payer perspective.

Do environmental concentrations of zinc oxide nanoparticle pose ecotoxicological risk to aquatic fungi associated with leaf litter decomposition?

Ecotoxicological risk of ZnO nanoparticles at environmental levels is a key knowledge gap for predicting how freshwater ecosystems will respond to nanoparticle pollution. A microcosm experiment was conducted to explore the chronic effects of ZnO nanoparticle at environmental concentrations (30, 300, 3000 ng L^-1) on aquatic fungi associated with the decomposing process of poplar leaf litter (45 days). ZnO nanoparticles led to 9-33% increases in fungal biomass after acute exposure (5 days), but 33-50% decreases after chronic exposure (45 days), indicating that the hormetic effect of ZnO nanoparticles at the environmental level may occur during acute exposure. Besides, ZnO nanoparticles had negative effects on microbial enzyme activity, especially on day 10, when the activities of N-acetylglucosaminidase, glycine-aminopeptidase, aryl-sulfatase, polyphenol oxidase, and peroxidase were significantly inhibited. After chronic exposure, the fungal community structure was significantly impacted by ZnO nanoparticles at 300 ng L^-1 due to the reduced proportion of Anguillospora, which eventually caused a significant decrease in litter decomposition rate. Therefore, ZnO nanoparticles may pose ecotoxicological effects on aquatic fungi even at a very low concentration and eventually negatively affect freshwater functioning.

Cost-effectiveness analysis of pembrolizumab plus chemotherapy with PD-L1 test for the first-line treatment of NSCLC

Background

Pembrolizumab (Pembro) in combination with chemotherapy has been approved for the treatment of pretreated advanced NSCLC in the United States and China for its significant efficacy. However, the cost‐effectiveness is unknown considering Pembro's high price. The impact of programmed death ligand 1 (PD‐L1) test on the cost‐effectiveness is also unknown. The current study assessed the cost‐effectiveness of combination therapy for nonsquamous NSCLC from the United States and China public payers’ perspective.

Materials and Methods

A literature‐based Markov model was conducted using KEYNOTE‐189 trial data to compare cost and quality‐adjusted life years (QALYs) of three treatment strategies for nonsquamous NSCLC: Pembro‐chemotherapy combination and chemotherapy strategy without PD‐L1 test, and treatment strategy according to their PD‐L1 status.

Results

In base case analysis, the combination strategy generated an additional 0.78 QALYs and 0.59 QALYs over chemotherapy in the United States and China respectively, resulting in an ICER of $132 392/QALY in the United States and $92 533/QALY in China. In the PD‐L1 ≥1% base case, the ICERs were $77 754/QALY and $56 768/QALY respectively in the United States and China for PD‐L1 test strategy. In the PD‐L1 ≥50% base case, the ICERs were $44 731/QALY and $34 388/QALY respectively in the United States and China for PD‐L1 test strategy. Lowering Pembro price can also partly decrease the ICERs.

Conclusion

Compared with chemotherapy, the combination strategy is not cost‐effective for the treatment of NSCLC in the American and Chinese health care system at WTP threshold of $100 000/QALY for the United States and $27 351/QALY for China. Using PD‐L1 test for patient selection and price reduction could improve the cost‐effective probabilities of immunotherapy for nonsquamous NSCLC.

Subresidue-Resolution Footprinting of Ligand-Protein Interactions by Carbene Chemistry and Ion Mobility-Mass Spectrometry

The knowledge of ligand-protein interactions is essential for understanding fundamental biological processes and for the rational design of drugs that target such processes. Carbene footprinting efficiently labels proteinaceous residues and has been used with mass spectrometry (MS) to map ligand-protein interactions. Nevertheless, previous footprinting studies are typically performed at the residue level, and therefore, the resolution may not be high enough to couple with conventional crystallography techniques. Herein we developed a subresidue footprinting strategy based on the discovery that carbene labeling produces subresidue peptide isomers and the intensity changes of these isomers in response to ligand binding can be exploited to delineate ligand-protein topography at the subresidue level. The established workflow combines carbene footprinting, extended liquid chromatographic separation, and ion mobility (IM)-MS for efficient separation and identification of subresidue isomers. Analysis of representative subresidue isomers located within the binding cleft of lysozyme and those produced from an amyloid-β segment have both uncovered structural information heretofore unavailable by residue-level footprinting. Lastly, a "real-world" application shows that the reactivity changes of subresidue isomers at Phe399 can identify the interactive nuances between estrogen-related receptor α, a potential drug target for cancer and metabolic diseases, with its three ligands. These findings have significant implications for drug design. Taken together, we envision the subresidue-level resolution enabled by IM-MS-coupled carbene footprinting can bridge the gap between structural MS and the more-established biophysical tools and ultimately facilitate diverse applications for fundamental research and pharmaceutical development.

Conjugation Site Analysis of Lysine-Conjugated ADCs

Lysine-conjugated antibody-drug conjugates (ADCs) are formed by attaching cytotoxic drugs to reactive lysine residues of monoclonal antibodies (mAbs) through chemical linkers. During production, the payloads are conjugated nonspecifically to lysine residues in mAbs, resulting in a heterogeneous mixture of ADCs with both different number and conjugation sites of drug payloads per mAb. On account of the drug conjugation sites and levels that both have significant influences on physical and pharmaceutical properties of ADCs, a reliable and straightforward approach for conjugation site analysis for ADCs is highly demanded. Herein, we used a lysine-conjugated ADC, Trastuzumab-MCC-DM1 (T-DM1), as a model ADC, and described an integrative strategy that combines the signature ion fingerprinting method for rapid and reliable filtering of DM1-conjugated peptides, and the normalized area quantitation approach for accurately gauging the conjugation levels for each identified site. This approach is believed to be readily applicable to other maytansinoid derivatives-modified ADCs, and more importantly, universally applicable to lysine-conjugated ADCs for both the recognition of conjugation sites and the measurement of conjugation levels.

Histamine2-Receptor Antagonists, Proton Pump Inhibitors, or Potassium-Competitive Acid Blockers Preventing Delayed Bleeding After Endoscopic Submucosal Dissection: A Meta-Analysis

Background: Endoscopic submucosal dissection (ESD) was commonly used for en bloc resection in gastric cancer and adenoma with the risk of delayed bleeding after ESD. We conducted a direct and indirect comparison meta-analysis to evaluate the best choice in preventing post-ESD bleeding among proton pump inhibitors (PPIs), histamine₂-receptor antagonists (H₂RAs), and the most widely used potassium-competitive acid blocker, vonoprazan.

Methods: The Pubmed, Cochrane Library, and Embase were searched for randomized trials. We pooled odds ratios (OR) for preventing post-ESD bleeding using meta-analysis.

Results: Sixteen randomized trials met the inclusion criteria including 2,062 patients. Direct comparisons showed slightly significant efficacy in PPIs rather than H₂RAs in preventing post-ESD bleeding [OR: 1.83; 95% confidence interval (CI): 1.10 to 3.05] and vonoprazan was better than PPIs (OR: 0.46; 95% CI: 0.25 to 0.86). The adjusted indirect comparison indicated vonoprazan was superior to H₂RAs (OR: 0.30, 95% CI: 0.12 to 0.74). In subgroup analysis, PPIs had similar efficacy as H₂RAs in 4 weeks, while PPIs were better than H₂RAs in 8 weeks’ treatment (OR: 1.91; 95% CI: 1.08 to 3.40). The superiority of vonoprazan than PPIs was more significant in combination therapy (OR: 0.18; 95% CI: 0.04 to 0.69). There was a significant difference in vonoprazan for 8 weeks of medication (OR: 0.44; 95% CI: 0.21 to 0.92).

Conclusions: The effects of vonoprazan is better than PPIs than H₂RAs in preventing bleeding after ESD. When vonoprazan combined with mucosal protective antiulcer drug in treatment or used in 8 weeks of medication, the efficacy may be even better.

Intestinal mucosal metabolites-guided detection of trace-level ginkgo biloba extract metabolome

The characterization of metabolome for poorly absorptive natural medicines is challenging. Previous identification strategy often relies on nontargeted scanning biological samples from animals administered with natural medicines in a data-dependent acquisition (DDA) mode by LC-MS/MS. Substances that displayed significant increases following drug administration are thus assigned as potential metabolites. The accurate m/z of precursors and the corresponding MS/MS fragment ions are used to match with herbal ingredients and to infer possible metabolic reactions. Nevertheless, the low concentration of these metabolites within complex biological matrices has often hampered the detection. Herein we developed a strategy termed intestinal mucosal metabolome-guided detection (IMMD) to tackle this challenge using ginkgo biloba (GBE) as an example. The rationale is that poorly absorptive natural products are usually concentrated and extensively metabolized by enterocytes before they enter the blood stream and distribute to other organs. Therefore, we firstly identified the metabolites from intestinal mucosa of GBE-treated rats, and then used the identified intestinal mucosal GBE metabolome as targeted repository for MRM analysis. The presences of these metabolites were subsequently examined in rat plasma, liver and brain. The resultant GBE metabolome showed significantly improved coverage with 39, 45 and 6 metabolites identified in plasma, liver and brain compared to 22, 16 and 0 metabolites from the corresponding regions via the DDA-based strategy. In addition, we integrated the previously reported nontargeted diagnostic ion network analysis to facilitate the characterization of GBE components, and a chemicalome-metabolome matching approach (CMMA) to assist the identity assignment of GBE metabolome with IMMD. Combinatorially, we establish a multi-faceted platform to streamline the workflow of metabolome characterization for herbal medicines of low bioavailability. The metabolome information is expected to shed light on the elucidation of metabolic pathways for natural products, and the underlying mechanisms of their biological efficacies.

A pooled meta-analysis of PD-1/L1 inhibitors incorporation therapy for advanced non-small cell lung cancer

Objective: Immune checkpoint inhibitors, especially the programmed cell death receptor-1/ligand 1 (PD-1/L1) inhibitors, displayed promising efficacy in non-small cell lung cancer (NSCLC) patients. Incorporation of anti-PD-1/L1 antibodies into other therapeutic regimens (including CTLA-4 inhibitors, chemotherapy, EGFR-TKIs and IDO inhibitors) is currently in active clinical research. This meta-analysis summarized recent developments in four combination regimens of PD-1/L1 inhibitors.

Methods: We searched PubMed, the Cochrane Library and the Embase database up to July 2018, on the combination therapy of PD-1/L1 inhibitors in NSCLC patients.

Results: Seventeen trials were finally included in the current meta-analysis. The combined objective response rate s (ORR) for PD-1/L1 inhibitors in combination with CTLA-4 inhibitors, chemotherapy, EGFR-TKIs, and IDO inhibitors were 32% (19%–44%), 49% (46%–53%), 55% (28%–83%) and 35% (20%–50%) respectively. The combined ORR for first line PD-1/L1 inhibitors combination with CTLA-4 inhibitors, chemotherapy, and EGFR-TKIs were 35% (17%–53%), 51% (46%–56%) and 43% (−7%–93%) respectively, and the combined ORR in the second or more line setting were 36% (8%–65%), 17% (−13%–46%), 39% (19%–59%) and 35% (20%–50%) respectively. The pooled 6-month progression-free survival rate (6m PFSr) and 1-year overall survival rate (1y OSr) for combination therapy of PD-1/L1 inhibitors with CTLA-4 inhibitors or chemotherapy were 35% or 65% (6m PFSr) and 31% or 70% (1y OSr) respectively. Anti-PD-1/L1 drugs combined with anti-CTLA-4 drugs exhibited a more potent efficacy on PD-L1 positive patients (OR=0.33, 95%CI: 0.12–0.88). This trend was not observed in patients receiving combination therapy of PD-1/L1 inhibitors with chemotherapy (OR=0.96, 95%CI: 0.51–1.78).

Conclusion: The included four combination regimens were potential treatment strategies and well tolerated for NSCLC patients. Further, the therapy lines and PD-L1 expression status were correlated with treatment efficacy.

Association Between Tumor Mutation Burden (TMB) and Outcomes of Cancer Patients Treated With PD-1/PD-L1 Inhibitions: A Meta-Analysis

Background: Programmed cell death 1 (PD-1) or programmed cell death ligand 1 (PD-L1) inhibitions are being strongly recommended for the treatment of various cancers, while the efficacy of PD-1/PD-L1 inhibitions varies from individuals. It is urgent to explore some biomarkers to screen the most appropriate cancer patients. Tumor mutation burden (TMB) as a potential alternative has been drawing more and more attention. Therefore, we conducted a meta-analysis to quantitatively explore the association between TMB and outcomes of PD-1/PD-L1 inhibitions.

Methods: We searched eligible studies that evaluated the association between TMB and the outcomes of PD-1/PD-L1 inhibitions from PubMed, Embase, and Cochrane database up to October 2018. The primary endpoints were the progression-free survival (PFS) and the overall survival (OS) in patients with high TMB or low TMB. The pooled hazard ratios (HR) for PFS and OS were performed by Stata.

Results: In this analysis, a total of 2,661 patients from eight studies were included. Comparing PD-1/PD-L1 inhibitions to chemotherapy, the pooled HR for PFS and OS in patients with high TMB was 0.66 [95% confidence interval (CI) 0.50 to 0.88; P = 0.004] and 0.73 (95% CI 0.50 to 1.08; P = 0.114), respectively, while the pooled HR for PFS and OS in patients with low TMB was 1.38 (95% CI 0.82 to 2.31; P = 0.229) and 1.00 (95% CI 0.80 to 1.24; P = 0.970), respectively. Meanwhile, comparing patients with high TMB to patients with low TMB, the pooled HR for PFS in patients treated with PD-1/PD-L1 inhibitions was 0.47 (95% CI 0.35 to 0.63; P = 0.000). Patients with high TMB showed significant benefits from PD-1/PD-L1 inhibitions compared to patients with low TMB.

Conclusion: Despite the present technical and practical barriers, TMB may be a preferable biomarker to optimize the efficacy of PD-1/PD-L1 inhibitions.

Integrative Omics Analysis Revealed that Metabolic Intervention Combined with Metronomic Chemotherapy Selectively Kills Cancer Cells

Metronomic chemotherapy, a relatively new dosing paradigm for anticancer therapy, is an alternative to traditional chemotherapy that uses maximal tolerated dose (MTD). Although these two dosing regimens both lead to tumor cell death, how cell metabolism is differentially affected during apoptosis remains elusive. Herein, we employed metabolomics to monitor the metabolic profiles of MCF-7 cells in response to the two dosing regimens that mimic MTD and MN treatments using a model chemotherapeutic drug, doxorubicin (Dox), and correlated the changes of metabolic genes examined by PCR array to integratively describe the reprogrammed metabolic patterns. We found glycolysis, amino acid, and nucleotide synthesis-associated metabolic pathways were activated in response to the MN treatment, whereas these pathways were inhibited in a pronounced way in response to the MTD treatment. Direct supplementation of key metabolites and pharmacological modulation of targeted metabolic enzymes can both regulate cell fates. Subsequently, we tested the combined use of MN dosing with targeted metabolic intervention using a normal cell line and found the combined treatment hardly affected its apoptotic rate. Our in vitro findings using MCF-7 and MCF-10A cells thus suggest the promising perspective of combining MN dosing of chemotherapeutic agents with metabolic modulation to selectively kill cancer cells rather than normal cells.

Ligand-protein target screening from cell matrices using reactive desorption electrospray ionization-mass spectrometry via a native-denatured exchange approach

Native mass spectrometry has been recognized as a powerful tool for probing interactions between small molecules, such as drugs and natural products, and target proteins. However, the presence of heterogeneous proteins and metabolites in real biological systems can alter the conformations of target proteins or compete with candidate ligands, thus necessitating a method for measuring binding stoichiometries in matrices aside from the extensively used pure/recombinant protein systems. Furthermore, some small molecule-protein interactions have a transient and low-affinity nature and thus can be mis-assigned as nonspecific binding complexes that are often formed during the native ESI process. A native-denatured exchange (NDX) approach was recently developed using a reactive desorption electrospray ionization-mass spectrometer (DESI-MS) setup to screen specific interacting partners. The method works by gradually increasing the composition of denaturing solvents contained in the DESI spray and thus conferring a switch from a native to denatured ionization environment. This change impairs three-dimensional structures of target proteins and disrupts specific ligand-protein interactions, leading to decreased holo/apo ratios. In contrast, ligand-protein complexes exhibiting different trends are assigned as nonspecific interactions. Herein, we applied the NDX approach to probe specific ligand-protein interactions in biological matrices. We first used mixtures of model ligands and proteins to examine the use of reactive DESI-MS in recognizing ligand-target binding in mixtures. Subsequently, we used the NDX approach to analyze binding affinity curves of ligands to target proteins spiked in cell lysates with the aid of size exclusion chromatography and demonstrated its use in probing specific ligand-protein interactions from cell matrices.

[An interpretation of an evidence-based guideline from the American Neuro-critical Care Society about the implementation of targeted temperature management]

OBJECTIVE

Targeted temperature management (TTM) is often used in neuro-critical care to minimize secondary neurologic injury and improve outcomes. Evidence-based implementation guideline of TTM was generated from clinical questions relevant to TTM implementation for neuro-critical care by experts recruited by the American Neuro-critical Care Society. Interpretation of this guideline would help the readers to understand the implementation of TTM, bring benefits to standardization of TTM application, and contribute to the solving of specific issues related to TTM implementation.

The potential phototoxicity of nano-scale ZnO induced by visible light on freshwater ecosystems

With the development of nanotechnology, nanomaterials have been widely applied in anti-bacterial coating, electronic device, and personal care products. NanoZnO is one of the most used materials and its ecotoxicity has been extensively studied. To explore the potential phototoxicity of nanoZnO induced by visible light, we conducted a long-term experiment on litter decomposition of Typha angustifolia leaves with assessment of fungal multifaceted natures. After 158 d exposure, the decomposition rate of leaf litter was decreased by nanoZnO but no additional effect by visible light. However, visible light enhanced the inhibitory effect of nanoZnO on fungal sporulation rate due to light-induced dissolution of nanoZnO. On the contrary, enzymes such as β-glucosidase, cellobiohydrolase, and leucine-aminopeptidase were significantly increased by the interaction of nanoZnO and visible light, which led to high efficiency of leaf carbon decomposition. Furthermore, different treatments and exposure time separated fungal community associated with litter decomposition. Therefore, the study provided the evidence of the contribution of visible light to nanoparticle phototoxicity at the ecosystem level.

Design and application of cationic amphiphilic β-cyclodextrin derivatives as gene delivery vectors

The nano self-assembly profiles of amphiphilic gene delivery vectors could improve the density of local cationic head groups to promote their DNA condensation capability and enhance the interaction between cell membrane and hydrophobic tails, thus increasing cellular uptake and gene transfection. In this paper, two series of cationic amphiphilic β-cyclodextrin (β-CD) derivatives were designed and synthesized by using 6-mono-OTs-β-CD (1) as the precursor to construct amphiphilic gene vectors with different building blocks in a selective and controlled manner. The effect of different type and degree of cationic head groups on transfection and the endocytic mechanism of β-CD derivatives/DNA nanocomplexes were also investigated. The results demonstrated that the designed β-cyclodextrin derivatives were able to compact DNA to form stable nanocomplexes and exhibited low cytotoxicity. Among them, PEI-1 with PEI head group showed enhanced transfection activity, significantly higher than commercially available agent PEI25000 especially in the presence of serum, showing potential application prospects in clinical trials. Moreover, the endocytic uptake mechanism involved in the gene transfection of PEI-1 was mainly through caveolae-mediated endocytosis, which could avoid the lysosomal degradation of loaded gene, and had great importance for improving gene transfection activity.

[Risk factors for allergic diseases in children aged 0-24 months in the Wuhu urban area, Anhui Province, China]

OBJECTIVE

To investigate the prevalence of allergic diseases in children aged 0-24 months in the Wuhu urban area of Anhui Province and risk factors for allergic diseases.

METHODS

Cluster random sampling was performed to select 600 children aged 0-24 months and their mothers from the Wuhu urban area, and a questionnaire survey was conducted to collect the data of disease history, family history, mothers' conditions during pregnancy, and child-rearing situation. Univariate analysis and multivariate logistic regression analysis were performed for such data.

RESULTS

Among the 597 children included in the analysis, 56 (9.4%) were diagnosed with allergic diseases in the past. The univariate analysis showed that the age, use of antipyretic and analgesic drugs, a history of allergy in the father or grandparents, and the consumption of fish, shrimps, crabs, and shellfish during pregnancy were significantly associated with past allergic diseases (P<0.05). The multivariate logistic regression analysis showed that the age and a history of allergy in the father or grandparents were positively associated with past allergic diseases (OR=4.0-4.9, 2.7, and 2.4 respectively; P<0.05), while frequent consumption of fish, shrimps, crabs, and shellfish during pregnancy was negatively associated with past allergic diseases (OR=0.3; P<0.05).

CONCLUSIONS

A family history of allergy is an independent risk factor for allergic diseases in children aged 0-24 months in the Wuhu urban area of Anhui Province, while frequent consumption of fish, shrimps, crabs, and shellfish during pregnancy is a protective factor.

Enhanced gene transfection performance and biocompatibility of polyethylenimine through pseudopolyrotaxane formation with α-cyclodextrin

Polyethylenimine (PEI), a commercially available gene transfection reagent, is a promising nonviral vector due to its inherent ability to efficiently condense genetic materials and its successful transfection performance in vitro. However, its low transfection efficiency in vivo, along with its high cytotoxicity, limit any further applications in gene therapy. To enhance the gene transfection performance and reduce the cytotoxicity of linear polyethylenimine, pseudopolyrotaxane PEI25k/CD and the polyrotaxanes PEI25k/CD-PA and PEI25k/CD-PB were prepared and their transfection efficiencies were then evaluated. The pseudopolyrotaxane PEI25k/CD exhibited better transfection efficiency and lower cytotoxicity than the transfection reagent linear PEI25k, even in the presence of serum. It also showed a remarkably higher cell viability, similar DNA protecting capability, and better DNA decondensation and release ability, and could be useful for the development of novel and safe nonviral gene delivery vectors for gene therapy.

Enhanced Structural and Electrochemical Stability of Self-Similar Rice-Shaped SnO2 Nanoparticles

A facile one-pot hydrothermal strategy is applied to prepare Co and F codoped SnO₂ (Co-F/SnO₂) nanoparticles, which exhibit a unique rice-shaped self-similar structure. Compared with the pristine and Co-doped counterparts (SnO₂ and Co/SnO₂), the Co-F/SnO₂ electrode demonstrates higher capacity, better cyclability, and rate capability as anode material for lithium ion batteries (LIBs). A high charge capacity of 800 mAh g^-1 can be successfully delivered after 50 cycles at 0.1 C, and a high reversible capacity of 700 mAh g^-1 could be retained after 100 cycles at 5 C. The excellent lithium storage performances of the Co-F/SnO₂ nanoparticles could be attributed to the synergetic effects of the doped Co and F, as well as the unique hierarchical self-similar structure with moderate oxygen defect and inactive pillars, which not only facilitates the fast diffusion of Li ions, but also stabilizes the structure during the electrochemical cycling.

[Risk factors for allergic diseases in children aged 0-24 months in the Wuhu urban area, Anhui Province, China]

OBJECTIVE

To investigate the prevalence of allergic diseases in children aged 0-24 months in the Wuhu urban area of Anhui Province and risk factors for allergic diseases.

METHODS

Cluster random sampling was performed to select 600 children aged 0-24 months and their mothers from the Wuhu urban area, and a questionnaire survey was conducted to collect the data of disease history, family history, mothers' conditions during pregnancy, and child-rearing situation. Univariate analysis and multivariate logistic regression analysis were performed for such data.

RESULTS

Among the 597 children included in the analysis, 56 (9.4%) were diagnosed with allergic diseases in the past. The univariate analysis showed that the age, use of antipyretic and analgesic drugs, a history of allergy in the father or grandparents, and the consumption of fish, shrimps, crabs, and shellfish during pregnancy were significantly associated with past allergic diseases (P<0.05). The multivariate logistic regression analysis showed that the age and a history of allergy in the father or grandparents were positively associated with past allergic diseases (OR=4.0-4.9, 2.7, and 2.4 respectively; P<0.05), while frequent consumption of fish, shrimps, crabs, and shellfish during pregnancy was negatively associated with past allergic diseases (OR=0.3; P<0.05).

CONCLUSIONS

A family history of allergy is an independent risk factor for allergic diseases in children aged 0-24 months in the Wuhu urban area of Anhui Province, while frequent consumption of fish, shrimps, crabs, and shellfish during pregnancy is a protective factor.

Preparation, Physicochemical Properties, and Transfection Activities of Tartaric Acid-Based Cationic Lipids as Effective Nonviral Gene Delivery Vectors

In this work two novel cationic lipids using natural tartaric acid as linking backbone were synthesized. These cationic lipids were simply constructed by tartaric acid backbone using head group 6-aminocaproic acid and saturated hydrocarbon chains dodecanol (T-C12-AH) or hexadecanol (T-C16-AH). The physicochemical properties, gel electrophoresis, transfection activities, and cytotoxicity of cationic liposomes were tested. The optimum formulation for T-C12-AH and T-C16-AH was at cationic lipid/dioleoylphosphatidylethanolamine (DOPE) molar ratio of 1 : 0.5 and 1 : 2, respectively, and N/P charge molar ratio of 1 : 1 and 1 : 1, respectively. Under optimized conditions, T-C12-AH and T-C16-AH showed effective gene transfection capabilities, superior or comparable to that of commercially available transfecting reagent 3β-[N-(N',N'-dimethylaminoethyl)carbamoyl]cholesterol (DC-Chol) and N-[2,3-dioleoyloxypropyl]-N,N,N-trimethylammonium chloride (DOTAP). The results demonstrated that the two novel tartaric acid-based cationic lipids exhibited low toxicity and efficient transfection performance, offering an excellent prospect as nonviral vectors for gene delivery.

Cholesterol derived cationic lipids as potential non-viral gene delivery vectors and their serum compatibility

Cholesterol derivatives M1-M6 as synthetic cationic lipids were designed and the biological evaluation of the cationic liposomes based on them as non-viral gene delivery vectors were described. Plasmid pEGFP-N1, used as model gene, was transferred into 293T cells by cationic liposomes formed with M1-M6 and transfection efficiency and GFP expression were tested. Cationic liposomes prepared with cationic lipids M1-M6 exhibited good transfection activity, and the transfection activity was parallel (M2 and M4) or superior (M1 and M6) to that of DC-Chol derived from the same backbone. Among them, the transfection efficiency of cationic lipid M6 was parallel to that of the commercially available Lipofectamine2000. The optimal formulation of M1 and M6 were found to be at a mol ratio of 1:0.5 for cationic lipid/DOPE, and at a N/P charge mol ratio of 3:1 for liposome/DNA. Under optimized conditions, the efficiency of M1 and M6 is greater than that of all the tested commercial liposomes DC-Chol and Lipofectamine2000, even in the presence of serum. The results indicated that M1 and M6 exhibited low cytotoxicity, good serum compatibility and efficient transfection performance, having the potential of being excellent non-viral vectors for gene delivery.

Improved Li storage performance in SnO2 nanocrystals by a synergetic doping

Tin dioxide (SnO₂) is a widely investigated lithium (Li) storage material because of its easy preparation, two-step storage mechanism and high specific capacity for lithium-ion batteries (LIBs). In this contribution, a phase-pure cobalt-doped SnO₂ (Co/SnO₂) and a cobalt and nitrogen co-doped SnO₂ (Co-N/SnO₂) nanocrystals are prepared to explore their Li storage behaviors. It is found that the morphology, specific surface area, and electrochemical properties could be largely modulated in the doped and co-doped SnO₂ nanocrystals. Gavalnostatic cycling results indicate that the Co-N/SnO₂ electrode delivers a specific capacity as high as 716 mAh g⁻¹ after 50 cycles, and the same outstanding rate performance can be observed in subsequent cycles due to the ionic/electronic conductivity enhancement by co-doping effect. Further, microstructure observation indicates the existence of intermediate phase of Li₃N with high ionic conductivity upon cycling, which probably accounts for the improvements of Co-N/SnO₂ electrodes. The method of synergetic doping into SnO₂ with Co and N, with which the electrochemical performances is enhanced remarkably, undoubtedly, will have an important influence on the material itself and community of LIBs as well.

Improved electrochemical performance of spinel LiMn(1.5)Ni(0.5)O4 through MgF2 nano-coating

A spinel LiMn1.5Ni0.5O4 (LMNO) cathode material synthesized by a sol-gel method is modified by MgF2 nano-coating via a wet coating strategy. The results of X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) showed that the MgF2 nano-coating layers do not physically change the bulk structure of the pristine material. Compared with the pristine compound, the MgF2-coated LMNO electrodes display enhanced cycling stabilities. Particularly, the 5 wt% MgF2-coated LMNO demonstrates the best reversibility, with a capacity retention of 89.9% after 100 cycles, much higher than that of the pristine material, 69.3%. The dQ/dV analysis and apparent Li(+) diffusion coefficient calculation prove that the kinetic properties are enhanced after MgF2 surface modification, which partly explains the improved electrochemical performances. Electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FTIR) data confirm that the MgF2 coating layer helps in suppressing the fast growth of the solid electrolyte interface (SEI) film in repeated cycling, which effectively stabilizes the spinel structure. Additionally, differential scanning calorimetry (DSC) tests show that the MgF2 nano-coating layer also helps in enhancing the thermal stability of the LMNO cathode.