ω-transaminase-catalyzed synthesis of (R)-2-(1-aminoethyl)-4-fluorophenol, a chiral intermediate of novel anti-tumor drugs

The chiral amine (R)-2-(1-aminoethyl)-4-fluorophenol has attracted increasing attentions in recent years in the field of pharmaceuticals because of its important use as a building block in the synthesis of novel anti-tumor drugs targeting tropomyosin receptor kinases. In the present study, a ω-transaminase (ωTA) library consisting of 21 (R)-enantioselective enzymes was constructed and screened for the asymmetric biosynthesis of (R)-2-(1-aminoethyl)-4-fluorophenol from its prochiral ketone. Using (R)-α-methylbenzylamine, D-alanine, or isopropylamine as amino donor, 18 ωTAs were identified with target activity and the enzyme AbTA, which was originally identified from Arthrobacter sp. KNK168, was found to be a potent candidate. The E. coli whole cells expressing AbTA could be used as catalysts. The optimal temperature and pH for the activity were 35-40 °C and pH8.0, respectively. Simple alcohols (such as ethanol, isopropanol, and methanol) and dimethyl sulfoxide were shown to be good cosolvents. High activities were detected when using ethanol and dimethyl sulfoxide at the concentrations of 5-20%. In the scaled-up reaction of 1-liter containing 13 mM ketone substrate, about 50% conversion was achieved in 24 h. 6.4 mM (R)-2-(1-aminoethyl)-4-fluorophenol was generated. After a simple and efficient process of product isolation and purification (with 98.8% recovery), 0.986 g yellowish powder of the product (R)-2-(1-aminoethyl)-4-fluorophenol with high (R)-enantiopurity (up to 100% enantiomeric excess) was obtained. This study established an overall process for the biosynthesis of the high value pharmaceutical chiral amine (R)-2-(1-aminoethyl)-4-fluorophenol by ωTA. Its applicable potential was exemplified by gram-scale production.

Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Thermal and electrical switchable wide-angle multi-band terahertz absorber

Multi-band terahertz (THz) absorbers have recently gained attention due to their favorable application prospects in communication, imaging, detection, and other fields. However, many multi-band THz absorbers are tuned by a single method, which limits their tuning effect. To address this issue, we propose a multi-band THz absorber that can be co-modulated by thermal and electrical methods. Our proposed absorber uses vanadium dioxide (VO2) to achieve this co-modulation. When VO2 is insulating, the frequency of the absorbing peaks originating from the lateral Fabry-Pérot resonance mode can be changed by adjusting the VO2 width. When VO2 is a conductor, the quality factor of the absorbing peak based on the inductor-capacitor resonance mode can be tuned by adjusting the width of VO2. By varying the top dielectric layer thickness, the frequency of the absorbing peaks can be tuned over a wide range. For devices with two or three layers of graphene nanoribbons-dielectric stacks, a modulation effect similar to that of varying dielectric layer thickness in a single-layer graphene device can be achieved simply by applying a 1 eV Fermi energy to graphene nanoribbons in different layers. By combining thermal and electrical modulation, the two or three-layer stacked device can be dynamically switched between four or six absorbing states, and a wider range of dynamic peak frequency modulation can be realized. Furthermore, the performance of the absorber does not deteriorate significantly at an incident angle of up to 70°. Our proposed thermal-electrical switchable wide-angle multi-band THz absorber provides a reference for the design, fabrication, and application of high-performance THz absorbers in different fields.

Efficacy of acupuncture as an adjunctive treatment to patients with stable COPD: a multicenter, randomized, sham-controlled trial protocol

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease and the third leading cause of death worldwide. Previous evidence has shown that acupuncture may be an effective complementary alternative therapy for stable COPD. However, large-sample, rigorously designed long-term follow-up studies still need to be completed. Notably, the relationship between the frequency of acupuncture and clinical efficacy in studies on acupuncture for stable COPD still needs further validation. This study aims to evaluate the efficacy and safety of acupuncture for stable COPD and further investigate the dose-effect relationship of acupuncture.

METHODS/DESIGN

This is a multicenter, randomized, controlled trial that uses central randomization to randomly allocate 550 participants in a 1:1:1:1:1 ratio to once a week acupuncture group, twice a week acupuncture group, three times a week acupuncture group, sham acupuncture group and waiting-list control group. The sham acupuncture group will receive placebo acupuncture treatments three times per week, and the waiting-list control group will not receive any form of acupuncture intervention. The study consists of a 2-week baseline, 12-week of treatment, and 52-week of follow-up. Patients with COPD between 40 to 80 years old who have received stable Western medication within the previous 3 months and have had at least 1 moderate or severe acute exacerbation within the past 1 year will be included in the study. Basic treatment will remain the same for all participants. The primary outcome is the proportion of responders at week 12. Secondary outcomes include the proportion of responders at week 64, change in the St. George's Respiratory Questionnaire (SGRQ) Scale, change in the Modified-Medical Research Council (mMRC) Scale, change in the COPD Assessment Test (CAT) Scale, change in the Lung Function Screening Indicators (LFSI), change in the 6-min walk distance (6-MWD), change in Short-Form 36 Health Survey (SF-36) Scale, the number of moderate and severe acute exacerbations and adverse event rate during the follow-up period.

DISCUSSION

This study will provide robust evidence on whether acupuncture is safe and effective for treating stable COPD. Meanwhile, comparing the differences in efficacy between different acupuncture frequencies will further promote the optimization of acupuncture for stable COPD.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (ChiCTR2200058757), on April 16, 2022.

Glucosylglycerol phosphorylase, a potential novel pathway of microbial glucosylglycerol catabolism

Glucosylglycerol (GG) is a natural compatible solute that can be synthesized by many cyanobacteria and a few heterotrophic bacteria under high salinity conditions. In cyanobacteria, GG is synthesized by GG-phosphate synthase and GG-phosphate phosphatase, and a hydrolase GGHA catalyzes its degradation. In heterotrophic bacteria (such as some Marinobacter species), a fused form of GG-phosphate phosphatase and GG-phosphate synthase is present, but the cyanobacteria-like degradation pathway is not available. Instead, a phosphorylase GGP, of which the coding gene is located adjacent to the gene that encodes the GG-synthesizing enzyme, is supposed to perform the GG degradation function. In the present study, a GGP homolog from the salt-tolerant M. salinexigens ZYF650T was characterized. The recombinant GGP catalyzed GG decomposition via a two-step process of phosphorolysis and hydrolysis in vitro and exhibited high substrate specificity toward GG. The activity of GGP was enhanced by inorganic salts at low concentrations but significantly inhibited by increasing salt concentrations. While the investigation on the physiological role of GGP in M. salinexigens ZYF650T was limited due to the failed induction of GG production, the heterologous expression of ggp in the living cells of the GG-producing cyanobacterium Synechocystis sp. PCC 6803 significantly reduced the salt-induced GG accumulation. Together, these data suggested that GGP may represent a novel pathway of microbial GG catabolism. KEY POINTS: • GGP catalyzes GG degradation by a process of phosphorolysis and hydrolysis • GGP-catalyzed GG degradation is different from GGHA-based GG degradation • GGP represents a potential novel pathway of microbial GG catabolism.

Targeting and Microenvironment-Activated Nanoreactor for Diabetic Chronic Wound Healing via Multienzyme Cascade Reactions

The development of cell-like nanoreactors with the ability to initiate biocatalytic cascades under special conditions holds tremendous potential for therapeutic applications. Herein, conformationally gated nanoreactors that respond to the acidic microenvironment of infected diabetic wounds were developed by cucur[8]bituril (CB[8])-based supramolecular assembly. The bioinspired nanoreactors exhibit not only self-regulated permeability and selectivity to control internal enzyme activities by substance exchange but also distinct binding specificities toward Gram-positive and Gram-negative bacteria via noncovalent modification with different ligands. The encapsulation of glucose oxidase (GOx), Fe3O4 nanozyme, and l-arginine (l-Arg) into the nanocarriers enables intelligent activation of multienzyme cascade reactions upon glucose (Glu) uptake to produce gluconic acid (GA) and hydrogen peroxide (H2O2), which is further converted into highly toxic hydroxyl radicals (·OH) for selective antibacterial activity. Moreover, acidic H2O2 promotes the oxidization of l-Arg, leading to the release of nitric oxide (NO). Consequently, this nanoreactor provides a multifunctional and synergistic platform for diabetic chronic wound healing by combining enzyme dynamic therapy with NO gas therapy to combat bacterial infections and inflammation under high blood Glu levels.

Interannual Variations in Terrestrial Net Ecosystem Productivity and Climate Attribution in the Southern Hilly Region of China

The vegetation ecosystem in the southern hilly region of China (SHRC) plays a crucial role in the country's carbon reservoir. Clarifying the dynamics of net primary productivity (NPP) in this area and its response to climate factors in the context of climate change is important for national forest ecology, management, and carbon neutrality efforts. This study, based on remote sensing and meteorological data spanning the period 2001 to 2021, aims to unveil the spatiotemporal patterns of vegetation productivity and climate factors in the southern hilly region, explore interannual variation characteristics of vegetation productivity with altitude, and investigate the response characteristics of NPP to various climate factors. The results indicate that from 2001 to 2021, the annual average NPP in the southern hilly region had a significant increasing trend of 2.13 ± 0.78 g m-2 a-1. The trend of NPP varies significantly with altitude. Despite a general substantial upward trend in vegetation NPP, regions at lower elevations exhibit a faster rate of increase, suggesting a diminishing difference in the NPP of different elevation ranges. The overall rise in average temperature has positive implications for the southern hilly region, while the impact of precipitation on vegetation NPP demonstrates noticeable spatial heterogeneity. Regions in which vegetation NPP is significantly negatively correlated with precipitation are mainly concentrated in the southern areas of Guangdong, Fujian, and Jiangxi provinces. In contrast, other regions further away from the southeastern coast tend to exhibit a positive correlation. Over the past two decades, there has been an asymmetry in the diurnal temperature variation in the SHRC, with the nighttime warming rate being 1.8 times that of the daytime warming rate. The positive impact of daytime warming on NPP of vegetation is more pronounced than the impact of nighttime temperature changes. Understanding the spatiotemporal patterns of NPP in the SHRC and the characteristics of its response to climate factors contributes to enhancing our ability to protect and manage vegetation resources amidst the challenges of global climate change.

[Effect of HCMV infection on immune reconstitution of CD8+T cells in children with allogeneic hematopoietic stem cell transplantation]

Objective: To investigate the risk factors for human cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation in children and the impact of human cytomegalovirus infection on post-transplant immune reconstitution. Methods: A Retrospective Co-Hort study design was used to include 81 children treated with allo-HSCT from January 2020 to March 2022 at the Department of Hematology, Capital Institute of Pediatrics, Beijing, China, and followed up for 1 year. Real-time quantitative PCR was used to detect positive detection of HCMV in children after allo-HSCT, multifactorial logistic regression modeling was used to analyze the risk factors leading to HCMV infection, and generalized estimating equation modeling was used to analyze the effect of HCMV infection on the T-cells of the children who received allo-HSCT. Results: The age M(Q1, Q3) of 81 children was 5.1 years (10 months, 13.8 years), and 50 (61.7%) were male. By the endpoint of follow-up, a total of 50 HCMV-positive cases were detected, with an HCMV detection rate of 61.7%; The results of multifactorial logistic regression modeling showed that children with grade 2-4 aGVHD had a higher risk of HCMV infection compared with grade 0-1 after transplantation [OR (95%CI) value: 2.735 (1.027-7.286)]. The results of generalized estimating equation modeling analysis showed that the number of CD3+T cells in HCMV-positive children after transplantation was higher than that in the HCMV-negative group [RR (95%CI) value: 1.34 (1.008-1.795)]; the ratio of CD4+T/CD8+T cells was smaller than that in the HCMV-negative group [RR (95%CI) value: 0.377 (0.202-0.704)]; the number of CD8+T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.435 (1.025-2.061)]; the number of effector memory CD8+T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.877 (1.089-3.236)]. Conclusion: Acute graft-versus-host disease may be a risk factor for HCMV infection in children after allo-HSCT; post-transplant HCMV infection promotes proliferation of memory CD8+T-cell populations and affects immune cell reconstitution.

[Preliminary analysis of seasonal pollen allergens of allergic rhinitis in a hospital of Nanchang City]

The study was aimed to analyze the seasonal pollen allergen spectrum of patients with allergic rhinitis (AR) in Nanchang city, and to provide evidence for improving the clinical diagnosis, treatment, prevention and epidemiology of seasonal AR. A retrospective analysis was conducted on the results of skin prick test (SPT) among 1 752 patients with AR in outpatient at Department of Otolaryngology, the First Affiliated Hospital of Nanchang University from September 2020 to August 2021 (a total of 1 069 males and 683 females, age ranged from 2 to 84 years old). SPSS 22.0 software was used to analyze the positive rates of main allergens and their differences in gender, age, and month of visit. Differences among groups were compared by student t test, Wilcox rank sum test, or χ2 test. The results showed that among 1 752 SPT-positive patients, the number of simple seasonal AR and the number of perennial combined seasonal AR were 102 (5.82%) and 281 (16.04%), respectively. There was no significant difference between male and female patients in positive seasonal pollen allergens (χ2=2.181, P>0.05), but the positive rate of indoor seasonal pollen allergens in males was higher than that in females (χ2=7.901, P<0.05). The seasonal pollen allergens ranking top 5 of the positive rates were willow (6.62%, 116/1 752), humulus scandens (5.71%, 100/1 752), rape (5.54%, 97/1 752), grey pigweed (4.62%, 81/1 752) and birch (3.60%, 63/1 752). The positive rates of indoor and seasonal pollen allergens increased first and then decreased in different age groups, and the highest positive rates of seasonal pollen allergens were in the age group of 31-40 years old, with statistical significance compared with other groups (χ2=61.269, P<0.05). The seasonal allergen positive rate showed two peaks in time: March to May and September to November. The positive rate of pollen in spring was 60.27% (132/219), which was significantly higher than that in autumn (39.73%,87/219) (χ2=9.247, P<0.05). The positive rate of pollen combination in spring and autumn was 68.29% (112/164), which was significantly higher than that in spring and autumn alone (18.9%,31/164) and (12.8%, 21/164) (χ2=14.731, P<0.05). In summary, pollen allergy in Nanchang City cannot be ignored, accounting for more than 20% of the total number of AR. The incidence of seasonal AR in Nanchang City showed two peaks (March to May and September to November). The common allergens for seasonal AR in Nanchang City were willow, humulus scandens, rape, grey chenopods and birch.

Genome-Wide Identification and Expression Pattern of MYB Family Transcription Factors in Erianthus fulvus

MYB family genes have many functions and are widely involved in plant abiotic-stress responses. Erianthus fulvus is an important donor material for stress-resistance genes in sugarcane breeding. However, the MYB family genes in E. fulvus have not been systematically investigated. In this study, 133 EfMYB genes, including 48 Ef1R-MYB, 84 EfR2R3-MYB and 1 Ef3R-MYB genes, were identified in the E. fulvus genome. Among them, the EfR2R3-MYB genes were classified into 20 subgroups. In addition, these EfMYB genes were unevenly distributed across 10 chromosomes. A total of 4 pairs of tandemly duplicated EfMYB genes and 21 pairs of segmentally duplicated EfMYB genes were identified in the E. fulvus genome. Protein-interaction analysis predicted that 24 EfMYB proteins had potential interactions with 14 other family proteins. The EfMYB promoter mainly contains cis-acting elements related to the hormone response, stress response, and light response. Expression analysis showed that EfMYB39, EfMYB84, and EfMYB124 could be significantly induced using low-temperature stress. EfMYB30, EfMYB70, EfMYB81, and EfMYB101 responded positively to drought stress. ABA treatment significantly induced EfMYB1, EfMYB30, EfMYB39, EfMYB84, and EfMYB130. All nine genes were induced using MeJA treatment. These results provide comprehensive information on EfMYB genes and can serve as a reference for further studies of gene function.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

Effect of MTA3 Inhibition of Glutamine Synthetase-Mediated Glutaminolysis on Radiosensitivity of Patients with Esophageal Cancer

PURPOSE/OBJECTIVE(S)

Metastasis-associated protein 3 (MTA3) can serve as a tumor suppressor in many cancer types. However, the role of MTA3 in radiosensitivity of patients with esophageal squamous cell cancer (ESCC) remains unclear. We thus investigated the function of MTA3 in radiosensitivity for ESCC, one of the most common digestive cancers.

MATERIALS/METHODS

The colony formation assay and nude mice xenograft tumor assay were performed to investigate the effect of MTA3 on radiosensitivity in ESCC. Glutamine consumption assay kit and glutamate production assay kit were used to assess the glutaminolysis. Glutaminase (GLS) Activity Assay Kit and Glutamine Synthetase (GS) Activity Assay Kit were used to analyze the activity of specific metabolic enzymes dominate glutaminolysis. The regulatory mechanism of glutaminolysis by MTA3 was confirmed using Chromatin immunoprecipitation assay and Gaussia luciferase assay. The expression levels of MTA3 and GS in ESCC primary tissues were evaluated using immunohistochemistry. Survival curves were plotted with the Kaplan-Meier method and compared by log-rank test.

RESULTS

The colony formation assay showed that MTA3 depletion and overexpression caused significantly higher and lower clonogenic survival after different doses of irradiation (IR), respectively. When these cells were subcutaneously injected into nude mice, the tumors derived from the cells with MTA3 overexpression and MTA3 knockdown were significantly smaller and bigger after IR, respectively. These findings suggest that MTA3 can enhance radiosensitivity in vitro and in vivo. Meanwhile, overexpressed and knockdown MTA3 can repress and expedite glutamine consumption and glutamate production uniformly, respectively. To determine how MTA3 acts on glutaminolysis, the activity of two specific metabolic enzymes dominate this metabolism, GS and GLS, were evaluated. It found that overexpressed and knockdown MTA3 can restrain and enhance the activity of GS, respectively, but have less effect on GLS. Moreover, the decreased radiosensitivity mediated by MTA3 knockdown is significantly increased when treated with GS inhibitor, suggesting that GS plays a crucial role in MTA3-mediated radiosensitivity enhancement. Mechanistically, Chromatin immunoprecipitation assay and Gaussia luciferase assay showed that MTA3 was recruited to the promoter of GS and suppressed GS transcription. However, knockdown of GATA3 abolished MTA3's repressive effect on GS and inhibited the MTA3's occupation on the promoter region of GS. These results collectively demonstrated that, in ESCC cells, MTA3 is recruited by GATA3 to inhibit GS expression, then ultimately represses glutaminolysis and enhances radiosensitivity. Finally, we showed that the ESCC patients in the MTA3low/GShigh group is significantly associated with shorter overall survival.

CONCLUSION

MTA3 is capable of enhancing radiosensitivity through downregulating GS and MTA3low/GShigh might be a potential prognostic factor for ESCC patients.

Combining Dosimetric and Radiomics Features for the Prediction of Radiation Pneumonitis in Locally Advanced Non-Small Cell Lung Cancer by Machine Learning

PURPOSE/OBJECTIVE(S)

This study aimed to analyze the dosimetric factors and radiomics features of tumor and lungs in locally advanced non-small cell lung cancer (LANSCLC) to establish machine learning models and improve the prediction of grade (G) 2 radiation pneumonitis (RP).

MATERIALS/METHODS

This study retrospectively collected data of 284 LANSCLC patients underwent concurrent chemoradiotherapy (CCRT) to a median dose of 64 Gy in 20-33 fractions between 2013 and 2021. Of this cohort, 21.1% of patients had ≥ G2 RP. There were 4 regions of interest (ROIs) had been identified in planning computed tomography images: gross tumor volume (GTV), ipsilesional lung (IL), contralesional lung (CL), and total lung (TL). We calculated the dose-volume histogram (DVH) from the lowest dose to the maximum dose increasing by degrees with 1 Gy, and extracted a total of 172 radiomics features from all the 4 ROIs. We selected the best predictors for classifying 2 groups of patients using a sequential backward elimination support vector machine model.

RESULTS

The best predictors for ≥ G2 RP were the combination of 8 radiomics features and 7 dosimetric factors in training group, and the validation group achieved an area under the curve (AUC) of 0.847 (accuracy, 80.38%; sensitivity, 78.95%; specificity, 81.82%). The eight radiomic features included 2 from GTV while 1, 2 and 3 from IL, CL and TL, respectively. For dosimetric factors, V65 of GTV, V20, V50 and V55 of IL, V10 of CL, V20 and V55 of TL appeared to be significantly related to symptomatic RP. These dosimetric factors should be constrained to less than 99.2%, 50.0%, 17.5%, 13.0%, 39.5%, 32.0%, and 6.6%, respectively.

CONCLUSION

Combining dosimetric factors and radiomics features within GTV, IL, CL and TL can improve the prediction of symptomatic RP in LANSCLC patients treated with CCRT. The results suggested the importance of V65 of GTV, V20, V50 and V55 of IL, V10 of CL, V20 and V55 of TL as predictors of symptomatic RP and provide useful information for optimization of treatment planning in the era of combination of radiotherapy and immunotherapy.

Chemical analysis of selected harmful and potentially harmful constituents and in vitro toxicological evaluation of leading flavoured e-cigarette aerosols in the Chinese market

Use of electronic cigarettes (e-cigarettes) has increased significantly over the past decade due to consumer perception that these products represent a less risky alternative to combustible cigarettes. E-liquids generally contain a simple mix of vegetable glycerin, propylene glycerol, nicotine, organic acids, and flavourings. Regulators require that harmful and potentially harmful constituents (HPHCs) that might cause harm to the consumer must be monitored in the aerosol generated by e-cigarettes and in cigarette smoke (CS). To quantify HPHCs in aerosols from commercial flavoured e-cigarettes in Chinese market, this study has systematically compared levels of HPHCs, including eight carbonyls, five volatile organic compounds, four tobacco-specific nitrosamines, 16 polycyclic aromatic hydrocarbons, and seven heavy metals, in the aerosols of four market-leading flavoured e-cigarettes and mainstream CS, alongside in vitro cytotoxicity and mutagenicity assays. The vast majority of HPHCs were either undetected or significantly lower in the e-cigarette aerosols than in commercial CS or reference CS (3R4F). Where HPHCs were detected, there were small variations among the different flavoured e-cigarettes. In the neutral red uptake and Ames assays, aqueous extracts of the e-cigarette aerosols did not induce obvious cytotoxicity or mutagenicity, whereas CS aqueous extract showed dose-related cytotoxicity and mutagenicity. Collectively, these results indicate that use of e-cigarettes might potentially lead to a significant reduction in exposure to harmful substances, with fewer cytotoxic and mutagenic effects, as compared with conventional smoking. Further studies based on human puffing conditions and longer evaluation periods will be needed to substantiate this potential.

The value of multimodal magnetic resonance imaging in breast cancer and its correlation with pathological features and prognosis

OBJECTIVE

This study aimed to explore the diagnostic value of multimodal magnetic resonance imaging (MRI) in breast cancer (BC) and its correlation with pathological features of the disease.

PATIENTS AND METHODS

Clinical data of 85 BC patients (malignant group) and 85 patients with benign breast diseases (benign group), admitted to 3201 Hospital of Xi'an Jiaotong University Health Science Center from May 2020 to May 2022, were retrospectively collected. Both groups underwent multimodal MRI examinations. We compared the differences in multimodal MRI examination parameters between the groups, as well as between patients with different pathological characteristics and prognoses in the malignant group. The correlation between multimodal MRI examination parameters and pathological features of BC was analyzed.

RESULTS

The apparent diffusion coefficient (ADC) of the malignant group was lower than that of the benign group, while the extravascular extracellular volume fraction (Ve), reaction rate constant (Kep), and volume transfer constant (Ktrans) of the malignant group were higher compared to the benign group (p<0.05). In the malignant group, patients with stage III+IV disease, lymph node metastases, and low differentiation had lower ADC values, and higher Ve, Ktrans, and Kep compared to patients with stage I+II disease, no lymph node metastasis, and medium to high differentiation (p<0.05). ADC value negatively correlated with the stage of the disease, lymph node metastases but positively correlated with the degree of differentiation (p<0.05). Ve, Ktrans, and Kep positively correlated with the stage of the disease and lymph node metastasis, and negatively correlated with the degree of differentiation (p<0.05). ADC value of patients with poor prognosis was lower, while Ve, Ktrans, and Kep were higher compared to patients with good prognosis (p<0.05). The Receiver operating characteristic (ROC) analysis showed that ADC, Ve, Ktrans, and Kep have certain predictive values for the poor prognosis of BC patients (p<0.05).

CONCLUSIONS

Multimodal MRI examination detected obvious differences in the examination parameters of BC patients, and the increase or decrease in these parameters is closely correlated with the pathological characteristics and prognosis of the disease. Multimodal MRI examination can be used for pathological evaluation and prognosis prediction in BC patients.

[The advance of ω-transaminase in chiral amine biosynthesis in China from the perspective of patents]

ω-transaminases are able to catalyze the reversible transfer of amino groups between diverse amino compounds (such as amino acids, alkyl amines, aromatic amines) and carbonyl compounds (such as aldehydes, ketones, ketoacids). ω-transaminases exhibit great application prospects in the field of chiral amine biosynthesis because of their desirable properties, such as wide range of substrates, high stereoselectivity, and mild catalytic conditions. It is therefore important for China to develop efficient, specific, and environment-friendly chiral amine production technologies with independent intellectual property rights, which is of great significance for the development of pharmaceutical, pesticide, and material industries. This review systematically summarizes the Chinese patents regarding ω-transaminase filed by Chinese institutions in the recent decade. The development of ω-transaminase resource, enzymatic property improvement by protein engineering, application in chiral amine synthesis, and development of production technologies are elaborated. This review will shed light on further basic and application studies of ω-transaminase.

Spatiotemporal Landscape for the Sophisticated Transformation of Protein Assemblies Defined by Multiple Supramolecular Interactions

Precise protein assemblies not only constitute a series of living machineries but also provide an advanced class of biomaterials. Previously, we developed the inducing ligand strategy to generate various fixed protein assemblies, without the formation of noncovalent interactions between proteins. Here, we demonstrated that controlling the symmetry and number of supramolecular interactions introduced on protein surfaces could direct the formation of unspecific interactions between proteins and induce various nanoscale assemblies, including coiling nanowires, nanotubes, and nanosheets, without manipulation of the protein's native surfaces. More importantly, these nanoscale assemblies could spontaneously evolve into more ordered architectures, crystals. We further showed that the transformation from the introduced supramolecular interactions to the interactions formed between proteins was crucial for pathway selection and outcomes of evolution. These findings reveal a transformation mechanism of protein self-assembly that has not been exploited before and may provide an approach to generate complex and transformable biomacromolecular self-assemblies.

[Effect of TFF3 on tight junction protein in eosinophilic chronic sinusitis and its related mechanism]

Objective: To study the effect of trefoil factor family (TFF) 3 on the expression of tight junctions (TJs) in the nasal mucosa epithelium of eosinophilic chronic rhinosinusitis (eCRS) and its mechanism. Methods: From September to December 2020, eligible patients from the Department of Otorhinolaryngology of the First Affiliated Hospital of Nanchang University were recruited, including 11 control patients and 37 patients with chronic rhinosinusitis with nasal polyps (CRSwNP), from whom nasal mucosa and nasal polyp tissue samples were collected. Immunohistochemistry (IHC) was used to detect the localization and expression intensity of TFFs (TFF1, TFF2 and TFF3) and TJs (occudin, claudin-1 and ZO-1) in nasal mucosa. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and western blot (WB) were used to detect the mRNA and protein expression. A cell model of tight junction injury in human nasal epithelial cells (HNECs) through stimulation with interleukin (IL)-13 was also established. The optimal modeling concentration and time for HNECs were determined, which were subsequently treated with TFF3 and/or a phosphoinositide 3-kinase (PI3K)-specific inhibitor (LY294002). Finally, RT-qPCR and WB were used to assess the effects of TFF3 on tight junctions and the PI3K/serine/threonine kinase (Akt) signaling pathway. Data were analyzed statistically using GraphPad Prism 7 software. Results: IHC results showed that the expression of TFF1 and TFF3 in nasal mucosa of eCRS group was significantly higher than that of control group (t=4.62, P=0.002; t=5.89, P<0.001), respectively, mainly expressed in goblet cell. The expression of occludin, claudin-1 and ZO-1 in the nasal mucosa of the eCRS group was lower than that of the control group (occludin t=3.98, P=0.019; claudin-1 t=5.15, P=0.002; ZO-1 t=5.42, P=0.001), respectively. WB results showed that the expression of TFF3 in non-eosinophilic chronic sinusitis (Non-eCRS) group and eCRS group was higher than that in the control group (t=3.62, P=0.036; t=5.93, P<0.001). The expression of occludin, claudin-1 and ZO-1 in eCRS group was lower than that in the control group (occludin t=5.14, P=0.002; claudin-1 t=6.35, P<0.001; ZO-1 t=6.64, P<0.001), respectively. The RT-qPCR results showed that compared with the control group, the levels of TFF1 and TFF3 mRNA were increased in the nasal mucosal epithelium of the Non-eCRS and eCRS groups (TFF1 t=3.98, P=0.046, t=4.89, P=0.002; TFF3 t=3.50, P=0.044, t=6.78, P<0.001). There was no statistically significant difference in TFF2 mRNA levels between the Non-eCRS and eCRS groups (t=1.34, P=0.061; t=3.37, P=0.055). Compared with the control group, Non-eCRS and eCRS groups showed a decrease in the mRNA levels of occludin, claudin-1 and ZO-1 (occludin t=4.27, P=0.011, t=5.61, P=0.007; claudin-1 t=3.62, P=0.036, t=6.80, P<0.001; ZO-1 t=3.47, P=0.047, t=7.86, P<0.001). The mRNA levels of TFF3 and TJs in eCRS nasal mucosa tissue showed a moderate positive correlation (occludin r=0.661, claudin-1 r=0.614, ZO-1 r=0.548, all P<0.001); TFF1 showed a low degree of positive correlation with the expression of occludin, claudin-1 and ZO-1 (occludin r=0.467, P=0.040; claudin-1 r=0.362, P=0.012; ZO-1 r=0.425, P=0.025). The establishment of cell models showed that compared with normal HNECs, the mRNA expression of TFF3 was most significantly increased at a concentration of 50 ng/ml stimulated by IL-13 (t=3.72, P=0.013); The mRNA expression of occludin, claudin-1 and ZO-1 decreased (occludin t=3.18, P=0.031; claudin-1 t=3.86, P=0.010; ZO-1 t=5.16, P=0.002). The expression of TFF3 mRNA increased most significantly after 15 hours of IL-13 stimulation (t=3.14, P=0.034); The mRNA expression of occludin, claudin-1 and ZO-1 decreased (occludin t=3.97, P=0.010; claudin-1 t=4.78, P=0.004; ZO-1 t=5.16, P=0.004). TJs damage model could be established by treating HNECs with 50 ng/ml IL-13 for 15 hours. Intervention experiments showed that compared with the IL-13 group, the IL-13+TFF3 group showed an increase in TJs mRNA expression (occludin t=6.10, P=0.009; claudin-1 t=5.90, P=0.013; ZO-1 t=9.44, P=0.007). Compared with the IL-13 group, the expression of TJs protein in the IL-13+TFF3 group increased (occludin t=3.23, P=0.013; claudin-1 t=9.40, P=0.017; ZO-1 t=2.23, P=0.032); The expression of TJs protein decreased in the IL-13+TFF3+LY294002 group (occludin t=4.73, claudin-1 t=8.77, ZO-1 t=3.51, all P<0.001). Compared with the IL-13+TFF3 group, the IL-3+TFF3+LY294002 group showed a decrease in PI3K and p-Akt/Akt protein expression (PI3K t=13.29, p-Akt/Akt t=10.30, all P<0.001). The increased mRNA and protein expression of occludin, claudin-1 and ZO-1 induced by TFF3 were also inhibited by LY294002. Conclusion: TFF3 can up-regulate the expression of occludin, claudin-1, and ZO-1 through PI3K/Akt pathway, and has a certain protective effect on the nasal mucosal epithelial barrier, providing a new idea for treating eCRS.

Recent advances in β-cyclodextrin-based materials for chiral recognition

In nature, enantiomers are pairs of chiral compounds, and have semblable chemical and physical properties but mostly show opposite biological effects when they enter an organism. Therefore, chiral recognition has a crucial research value in the fields of medicine, food, biochemistry, etc. Cyclodextrins (CDs) are produced by cyclodextrin glucosyltransferase in some species of bacillus on starch and include three main members α-, β-, and γ-CD with six, seven and eight units of glucose, respectively. With a hydrophilic external cavity and a hydrophobic internal cavity, β-CD can also combine with a variety of materials (e.g., graphene, nanoparticles, COFs, and OFETs) to enhance the chiral recognition of guest molecules in a chiral sensor. This review presents the progress of β-CD modification with different materials for chiral recognition and describes in detail how different materials assist β-CD in chiral recognition and improve the effect of β-CD chiral discrimination.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

Light-controlled artificial transmembrane signal transduction for 'ON/OFF'-switchable transphosphorylation of an RNA model substrate

Inspired by nature, it is of significant importance to design and construct biomimetic signaling systems to mimic natural signal transduction. Herein, we report an azobenzene/α-cyclodextrin (α-CD)-based signal transduction system with three functional modules: a light-responsive headgroup, lipid-anchored group, pro-catalyst tailgroup. The transducer can be inserted into the vesicular membrane to trigger the transmembrane translocation of molecules under the activation of light, forming a ribonuclease-like effector site and leading to the transphosphorylation of the RNA model substrate inside the vesicles. Moreover, the transphosphorylation process can be reversibly turned 'ON/OFF' over multiple cycles by the activation and deactivation of the pro-catalyst. This artificial photo-controlled signal transduction successfully constructs a signal responsive catalysis system across the membrane to utilize light to reversibly control the internal transphosphorylation process of an RNA model substrate, which might provide a new strategy for future design to utilize exogenous signals for implementing endogenous enzyme manipulation and gene regulation.

[Evaluation effect of COMPERA 2.0 risk assessment model on prognosis of Chinese patients with pulmonary arterial hypertension]

Objectives: To clarify the evaluation effect of COMPERA 2.0 risk assessment model on prognosis of pulmonary arterial hypertension (PAH) in China. Methods: Patients with newly diagnosed PAH admitted in Fuwai hospital between April 2019 and March 2022 were enrolled retrospectively and divided in low, intermediate-low, intermediate-high and high strata by scores of COMPERA 2.0 risk assessment model. All the patients were followed up by clinic or telephone. The primary endpoint was defined as a composite of all-cause mortality, exacerbated heart failure and aggravated symptoms. Kaplan-Meier analysis and log-rank trend test were used to determine the risk of endpoints among the 4 groups. Multivariate Cox proportional hazards regression were used to analyze the association between COMPERA 2.0 scores and prognosis in patients with PAH. Results: A total of 951 patients with PAH were enrolled in this study. The age [M (Q₁, Q₃)] of the patients was 35 (28, 47) years, of which 706 cases (74.2%) were females. A total of 328 cases (34.5%) were assigned in low strata, 264 cases (27.8%) in intermediate-low strata, 193 cases (20.3%) in intermediate-high strata, and 166 cases (17.5%) in high strata. During the duration [M (Q₁, Q₃)] of follow-up after discharge of 1.8 (1.0, 2.8) years, the primary endpoint was occurred in 12.8% (42/328), 21.2% (56/264), 28.5% (55/193) and 42.8% (71/166) of low, intermediate-low, intermediate-high and high strata, respectively. The rates of primary endpoint were significantly increased with strata rising (P<0.001). Multivariate Cox proportional hazards regression showed that COMPERA 2.0 risk scores were associated with the primary endpoints in PAH patients (HR=1.801, 95%CI: 1.254-2.588, P=0.001) after adjusting confounders. Conclusion: COMPERA 2.0 risk assessment model is a simple and effective tool for evaluating the prognosis of newly diagnosed PAH patients in China.

[Comparative analysis of clinical diagnosis and treatment guidelines for drug-induced liver injury at home and abroad]

Drug-induced liver injury influencing factors are complex and have diverse clinical manifestations. Simple and reliable diagnostic methods are still deficient, and further classification of toxicological mechanisms is required. There are numerous pertinent discrepancies between domestic and international guidelines aimed at drug-induced liver injury diagnosis and treatment, with partial to no consensus on the content. The American Gastroenterological Association's 2021 Clinical Guidelines, the Asia-Pacific Association for the Study of the Liver's 2021 Consensus Guidelines, the Council for International Organizations of Medical Sciences' 2020 International Consensus, the European Society's Hepatology Committee's 2019 Clinical Practice Guidelines, and the 2015 Chinese Medical Association Guidelines are five influential clinical guidelines on drug-induced liver injury at home and abroad. The epidemiology, risk factors, diagnosis and evaluation, treatment management, and other contents, particularly traditional Chinese medicine, were compared and analyzed using other relevant consensus opinions or guidelines in order to improve understanding and provide a reference for clinical diagnosis and treatment of drug-induced liver injury.

A robust high selectivity fluorescence turn-on nanoprobe for peroxynitrite detection in inflammatory cells and mice

Changed levels of intracellular peroxynitrite anion (ONOO^-) are closely related to the occurrence and development of inflammation. Specific imaging of ONOO^- at sites of inflammation can be of great significance not only for inflammation diagnosis but also for obtaining a deeper understanding of the role of ONOO^- in inflammation. Therefore, there is an urgent need for constructing some reliable tools to study the relationship between ONOO^- and inflammation in biosystems. In this work, we developed a robust high selectivity fluorescence turn-on nanoprobe (Rhb-ONOO) for inflammation-targeted imaging of ONOO^-. The Rhb-ONOO was obtained by self-assembly of amphiphilic Rhb-ONOO, which was constructed by the condensation reaction of the hydrophobic, ONOO^--response and deep red-emitting fluorophore (Rhb) with hydrophilic biopolymer glycol chitosan (GC). Rhb-ONOO showed rapid response towards ONOO^- during 60 s, high sensitivity with 19-fold enhancement of fluorescence intensity ratio (I₆₂₈/I₀), and excellent selectivity towards ONOO^- over other analytes as well as a good linear relationship was observed between the I₆₂₈/I₀ and the ONOO^- concentration range 0-1 μM, with an excellent limit of detection (LOD) of 33 nM. Impressively, it was successfully employed Rhb-ONOO for ONOO^- imaging in living inflammatory cells and drug-induced inflammatory mice, illustrating nanoprobe Rhb-ONOO has excellent potential for further study ONOO^--related inflammatory diseases.

Release of Interface Confined Water Significantly Improves Dentin Bonding

Water residue and replacement difficulty cause insufficient adhesive infiltration in demineralized dentin matrix (DDM), which produces a defective hybrid layer and thus a bonding durability problem, severely plaguing adhesive dentistry for decades. In this study, we propose that the unique properties of a highly hydrated interface of the porous DDM can give rise to 1 new type of interface, confined liquid water, which accounts for most of the residue water and may be the main cause of insufficient infiltration. To prove our hypothesis, 3 metal ions with increasing binding affinity and complex stability (Na⁺, Ca²⁺, and Cu²⁺) were introduced respectively to coordinate negatively charged groups such as -PO₄^3-, -COO^- abundant in the DDM interface. Strong chelation of Ca²⁺ and Cu²⁺ rapidly released the confined water, significantly improving penetration of hydrophobic adhesive monomers, while Na⁺ had little effect. A significant decrease of defects in the hybrid layer and a much decreased modulus gap between the hybrid layer and the adhesive layer greatly optimized the microstructure and micromechanical properties of the tooth-resin bonding interface, thus improving the effectiveness and durability of dentin bonding substantially. This study paves the way for a solution to the core scientific issue of contemporary adhesive dentistry: water residue and replacement in dentin bonding, both theoretically and practically.

α-D-1,3-glucan from Radix Puerariae thomsonii improves NAFLD by regulating the intestinal flora and metabolites

Radix Puerariae thomsonii, the root of the botanical family Fabaceae species Pueraria montana var. thomsonii (Benth.) MR Almeida, can be used as food or medicine. Polysaccharides are important active constituents of this root. A low molecular weight polysaccharide, RPP-2 having α-D-1,3-glucan as the main chain, was isolated and purified. RPP-2 could promote the growth of probiotics in-vitro. Therefore, the effects of RPP-2 on a high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) C57/BL6J mouse models were investigated. RPP-2 could reduce HFD-induced liver injury by reducing inflammation, glucose metabolism, and steatosis, thereby improving NAFLD. RPP-2 regulated the abundances of intestinal floral genera Flintibacter, Butyricicoccus, and Oscillibacter, and their metabolites Lipopolysaccharide (LPS), bile acids, and short-chain fatty acids (SCFAs), thereby improving inflammation, lipid metabolism, and energy metabolism signaling pathways. These results confirmed that RPP-2 play a prebiotic role by regulating intestinal flora and microbial metabolites, playing a multi-pathway and multi-target role in improving NAFLD.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

Inhibition of coagulation factor XI attenuates inflammation in myocardial ischemia/reperfusion injury

Background

Increasing evidence suggests that FXI is an attractive target for antithrombotic therapy because it reduces thrombosis without increasing bleeding risk. Patients with decreased levels of FXI are at reduced risk of cardiovascular diseases and thromboembolic events. We have already revealed that depletion of FXI inhibits the vascular coagulation-inflammatory circuit in angiotensin II-induced arterial hypertension. However, the effect of FXI depletion on cardiac inflammation and vascular function in ischemia/reperfusion (I/R) injury is unknown.

Purpose

Using FXI-depleted mice to investigate the role of FXI in inflammation response post cardiac I/R injury.

Methods

8–12 weeks old C57BL/6J male mice were injected intraperitoneally with FXI antisense oligonucleotide (FXI ASO) or scrambled controls for a period of 2 weeks. Then we temporarily ligated the left anterior descending (LAD) for 45 minutes to induce myocardial ischemia, followed by the reperfusion for 72 hours (ischemia/reperfusion injury, IRI). Myocardial inflammation and vascular function were analyzed by flow cytometry, real-time PCR, vascular relaxation studies from isolated aortic segment in organ chamber and chemiluminescence photon counting of oxidative burst in whole blood.

Results

FXI ASO treatment reduced hepatic FXI mRNA levels and prolonged activated partial thromboplastin time. Compared to scrambled ASO injected mice, oxidative burst from whole blood and endothelial dysfunction were decreased in FXI ASO injected mice with IRI. Compared to control groups, depletion of FXI attenuated cardiac infiltration of CD45+CD11b+ cells, especially LyG-LyChigh monocytes and LyG+ neutrophils at day 3 in I/R injury. Furthermore, the expression levels of adhesion molecules and expression of pro-inflammatory cytokines, such as Vcam-1, CCL2, IL-6 and IL-1b, in ischemic myocardium were significantly decreased in the FXI depleted mice of I/R injury.

Conclusion

Our results suggest that Inhibition of FXI leads to reduction of vascular dysfunction and ROS production in I/R injury, as well as attenuation of the inflammatory response and the influx of inflammatory cells in ischemic myocardium. This indicates that FXI could be a potential target for further treatment in cardiac IRI.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): TICARDIO project has received funding from the European Union's Horizon 2020 research and Innovation programme under the Marie Skłodowska-Curie grant agreement No 813409.

[Correlation between heart rate index, SBPpeak-to-SBPrest ratio and peak oxygen consumption in patients with chronic heart failure]

Objective: To investigate the correlation between heart rate index (HRI), systolic blood pressure(SBP) peak-to-SBPrest ratio (SBPR) and peak oxygen consumption (peakVO₂) in patients with chronic heart failure (CHF), and discuss the possibility of using HRI and SBPR collected during exercise to assess the exercise tolerance of CHF patients in the absence of gas analysis. Methods: In this cross-sectional study, a total of 547 patients with CHF who underwent cardiopulmonary exercise test(CPET) in Tongji Hospital Heart Rehabilitation Center Affiliated to Tongji University from March 2007 to December 2018 were collected retrospectively, focusing on their clinical data including age, gender, type of heart failure,BMI as well as data collected during their CPETs, such as peakVO₂, HRI and SBPR. Spearman univariate correlation analysis was used for statistical analysis, to unveil the correlations between peakVO₂ and those parameters, and multiple linear regression analysis was also conducted. Results: A total of 547 CHF patients conducting CPET were included in this research, of which 447 were male, at age of 63(56, 69). Univariate analysis indicates that HRI, SBPR and peakVO₂ showed significant positive correlation (r=0.323, 0.263, respectively, all P<0.001); Age and peak VO₂ showed significant negative correlation(r=-0.207, P<0.001); Male patients showed peakVO₂ higher than female(r=-0.229, P<0.001); PeakVO₂ of heart failure with reduced ejection fraction(HFrEF) was lower than heart failure with mid-range ejection fraction(HFmrEF)and heart failure with preserved ejection fraction(HFpEF) (r=0.181, P<0.001). Body mass index (BMI) had no significant correlation with peakVO₂ (P>0.05). Multivariate linear regression analysis showed that the HRI, SBPR were positively correlated with peakVO₂(t=7.68, 5.08, respectively, all P<0.05), while age and BMI showed negative correlation with peakVO₂(t=-5.43, -0.31, respectively, all P<0.05). PeakVO₂ of male was higher than female(t=-6.03, P<0.05), and peakVO₂ of HFrEF was lower than those of HFmrEF and HFpEF(t=3.17, 4.48, respectively, all P<0.05). A linear equation (F=33.52, adjusted R²=0.29) could be constructed: peakVO₂=10.65(male) or 8.53(female)+4.26HRI+3.31SBPR-0.07age-0.13BMI+0(HFrEF) or 1.05 (HFmrEF) or 1.62(HFpEF). Conclusion: HRI and SBPR are positively correlated with peakVO₂. In the absence of gas analysis, it is possible to apply HRI and SBPR during exercise to predict exercise tolerance in patients with CHF.

Psoriasis may increase the risk of lung cancer: a two-sample Mendelian randomization study

BACKGROUND

Although many studies have indicated that Psoriasis (PsO) could contribute to the risk of lung cancer, no study has reported a clear causal association between them. Our aim was to explore the potential causal association between PsO and the lung cancer risk using Mendelian randomization (MR) design.

METHODS

To explore a causal association between the PsO and lung cancer, we used large-scale genetic summary data from genome-wide association study (GWAS), including PsO (n = 337 159) and lung cancer (n = 361 586), based on previous observational studies. Our main analyses were conducted by inverse-variance weighted (IVW) method with random-effects model, with a complementary with the other two analyses: weighted median method and MR-Egger approach.

RESULTS

The results of IVW methods demonstrated that genetically predicted PsO was significantly associated with higher odds of lung cancer, with an odds ratio (OR) of 1.06 (95%CI, 1.01-1.12; P = 0.02). Weighted median method and MR-Egger regression also demonstrated directionally similar results (All P < 0.05). In addition, both funnel plots and MR-Egger intercepts indicated no directional pleiotropic effects between PsO and lung cancer.

CONCLUSIONS

Our study provided potential evidence between genetically predicted PsO and lung cancer, which suggested that enhanced screening for lung cancer allows early detection of lung cancer.

Single-Molecule Observation of Selenoenzyme Intermediates in a Semisynthetic Seleno-α-Hemolysin Nanoreactor

The development of monitoring methods to capture short-lived intermediates is crucial for kinetic mechanism validation of enzymatic reaction steps. In this work, a semisynthetic selenoenzyme nanoreactor was constructed by introducing the unnatural amino acid (Sec) into the lumen of the α-hemolysin (αHL) nanopore. This nanoreactor not only created a highly confined space to trap the enzyme-substrate complex for a highly efficient antioxidant activity but also provided a single channel to characterize a series of selenoenzyme intermediates in the whole catalytic cycle through electrochemical analysis. In particular, the unstable intermediate of SeOH can be clearly detected by the characteristic blocking current. The duration time corresponding to the lifetime of each intermediate that stayed within the nanopore was also determined. This label-free approach showed a high detection sensitivity and temporal-spatial resolution to scrutinize a continuous enzymatic process, which would facilitate uncovering the mysteries of selenoenzyme catalysis at the single-molecule level.

"On/Off" Switchable Sequential Light-Harvesting Systems Based on Controllable Protein Nanosheets for Regulation of Photocatalysis

A controllable protein nanostructures-based "On/Off" switchable artificial light-harvesting system (LHS) with sequential multistep energy transfer and photocatalysis was reported herein for mimicking the natural LHS in both structure and function. Single-layered protein nanosheets were first constructed via a reversible covalent self-assembly strategy using cricoid stable protein one (SP1) as building blocks to realize an ordered arrangement of pigments. Fluorescent chromophores like carbon dots (CDs) can be precisely distributed on the protein nanosheets superficially via electrostatic interactions and make the ratio between donors and acceptors adjustable. After being anchored with a photocatalysis center (eosin-5-isothiocyanate, EY), the constructed LHS could sequentially transfer energy between two kinds of chromophores (CD1 and CD2), and further transfer to EY center with a high efficiency of 84%. Interestingly, the Förster resonance energy transfer (FRET) process of our LHS could be reversibly "On/Off" switched by the redox regulated assembly and disassembly of SP1 building blocks. Moreover, the LHS has been further proved to promote the yield of a model cross-coupling hydrogen evolution reaction and regulate the process of the reaction with the FRET process "On/Off" state.

Morphological Selectivity of a Protein Self-Assembly System with a Repertoire of Diverse Interaction Modes

Multiple metal chelating sites were incorporated onto the second mitochondria-derived activator of caspase (SMAC) building blocks. The combination of different binding sites generated a repertoire of diverse binding modes, among which two different microfilament types (small and large) with distinct patterns were selected under thermodynamic control. Furthermore, the two microfilaments exhibited a pronounced secondary assembly trend due to the potential noncovalent interactions on the protein surfaces. Coupled with stereoselectivity, they presented a strong self-recognition effect and underwent two distinct reassembly patterns. That is, the large filaments self-associated in pairs to form "interlocked chain" structures, while the small ones twisted to form protein helical bundles. This work represents one of the few studies of selective self-assembly of self-assembled protein assemblies. Such an idea may provide inspiration for constructing more sophisticated protein architectures in the future.

A new HClO-activated "turn-off" mitochondria-targetable NIR fluorescent probe for imaging of osteoarthritis in vivo

Hypochlorous acid (HClO) as a biomarker of inflammation has been implicated in redox signaling and combating microbial infection. Therefore, it is of great significance to develop an efficient method for detection and analysis of HClO in osteoarthritis. Herein, a new"turn-off" mitochondria-targetable NIR fluorescent probe, NIR-ClO, was reported for specific analysis and imaging of osteoarthritis response-related HOCl levels in vitro and in vivo. In the presence of HClO, due to the specific HOCl-triggered C = C bond cleavage reaction, NIR-ClO obtained a high sensitive and selective fluorescence "On-Off" response toward HClO with a good limit of detection(LOD) as low as 28.3 nM, and showed a fast response time (<60 s) , which allow it to be used for detection of HClO under a simulated physiological condition. In addition, NIR-ClO was successfully used to imaging of HClO in living RAW264.7 cells and osteoarthritis model rat. The results suggest that NIR-ClO is a robust tool for future studies on diagnosis osteoarthritis.

Supramolecularly regulated artificial transmembrane signal transduction for 'ON/OFF'-switchable enzyme catalysis

An artificial signal transduction model with a supramolecular recognition headgroup, a membrane anchoring group, and a pro-enzyme catalysis endgroup was constructed. The transmembrane translocation of the transducer can be reversibly regulated by competitive host-guest complexations as an input signal to control an enzyme reaction inside the lipid vesicles.

Biological sources, metabolism, and production of glucosylglycerols, a group of natural glucosides of biotechnological interest

Glucosylglycerols (GGs) are a group of functional heterosides comprising glycerol and glucose. In nature, they are mainly produced by many moderately salt-tolerant cyanobacteria as compatible solutes in a salt-dependent manner and synthesized in a few higher plants and fermentation processes. Because of their many interesting physicochemical properties and biological activities, such as low sweetness, low hygroscopicity, high water-holding capacity, excellent biocompatibility, favorable performance in protecting macromolecules, and antitumor activity, GGs exhibit large application potential in the fields of cosmetics, health care, food service, enzyme production, and pharmaceuticals. Many in vitro systems using different members of the GH (glycoside hydrolase) family have been established for the enzymatic synthesis of GGs, and a few of them are in use for commercial production. Based on a good understanding of the genetic bases, biochemical processes, and regulatory mechanisms of GG metabolism in microorganisms (mainly cyanobacteria), in recent years GG production technologies with in vivo systems have also been developed by applying metabolic and bioprocess engineering to a few native or heterologous microbial cell factories. This successfully provides the market GG products with an alternative source. With the further elucidation of details about the biological functions of GGs and related mechanisms, the application scope of GGs will be greatly expanded. In the present review, the biological sources and physiological roles of GGs, the molecular bases and regulation of GG metabolism, and the recent progress in GG production and application are systematically summarized. A few new questions that have arisen in the basic research of GGs and perspectives on GG application are also discussed.

Radix Puerariae thomsonii polysaccharide (RPP) improves inflammation and lipid peroxidation in alcohol and high-fat diet mice by regulating gut microbiota

Polysaccharides are the important active constituents of Radix Puerariae thomsonii. Numerous studies have shown that polysaccharides can regulate gut microbiota, repair intestinal barrier, and affect the microbiota-intestine-liver axis, thereby showing therapeutic effects on metabolic disorders. In this study, Radix Puerariae thomsonii polysaccharide (RPP) was extracted from Radix Puerariae thomsonii. The average Mw of RPP was determined to be 1.09 × 10⁵ Da and the monosaccharide composition showed it consisted of glucose. The effects and underlying mechanisms of RPP on fatty liver were studied using C57/BL6J mice induced by alcohol and high-fat diet. The results showed that the oral supplementation of RPP could alleviate alcohol and high-fat diet-induced hepatic injury and steatosis. RPP also promoted intestinal barrier integrity and reduced inflammation through NF-κB signaling pathway. RPP could ameliorate the lipid peroxidation by AMPK/NADPH oxidase signaling pathway. Additionally, these improvements might be related to the enrichment of intestinal bacteria Parabacteroides (promote intestinal barrier integrity) and Prevotellaceae UCG 001 (activation of AMPK signaling pathway). These results demonstrated that RPP could improve inflammation and lipid peroxidation in the alcohol and high-fat diet mouse by restoring the intestinal barrier integrity and regulating the gut microbiota. This suggested that RPP was a potential food supplement for the treatment of fatty liver disease.

A FRET-based ratiometric fluorescent probe for hydrogen polysulfide detection in living cells and zebrafish

Hydrogen polysulfide (H₂S_n, n > 1) is an important active sulfur molecule (RSS) in organisms, which have been considered to be involved in redox signaling and cytoprotective processes. In this work, in order to quickly and accurately detect H₂S_n in biosystems, 2-fluoro-5-nitrobenzoic ester was used as the response moiety for H₂S_n, and the FRET strategy was adopted to effectively connect the donor (6-hydroxy-2-naphthoic acid) and acceptor (4-substituted-1,8-naphthalimide) to construct a new ratiometric H₂S_n fluorescent probe NPNA-H₂S_n. NPNA-H₂S_n exhibited a more than ∼ 8.0-fold ratio enhancement towards H₂S_n at I₄₅₀/I₅₂₆ and a very high sensitivity with a very low detection limit of 40.3 nM. Impressive, NPNA-H₂S_n was further used for fluorescence imaging of H₂S_n in living cells and zebrafish, which showed high-clear ratiometric images. Therefore, we have demonstrated that NPNA-H₂S_n could be applied for ratiometric images of endogenous H₂S_n in living biosystems and provide a powerful molecular tool for evaluating the physiological and pathological functions of H₂S_n.