A 2-year locomotive exploration and scientific investigation of the lunar farside by the Yutu-2 rover

The lunar nearside has been investigated by many uncrewed and crewed missions, but the farside of the Moon remains poorly known. Lunar farside exploration is challenging because maneuvering rovers with efficient locomotion in harsh extraterrestrial environment is necessary to explore geological characteristics of scientific interest. Chang'E-4 mission successfully targeted the Moon's farside and deployed a teleoperated rover (Yutu-2) to explore inside the Von Kármán crater, conveying rich information regarding regolith, craters, and rocks. Here, we report mobile exploration on the lunar farside with Yutu-2 over the initial 2 years. During its journey, Yutu-2 has experienced varying degrees of mild slip and skid, indicating that the terrain is relatively flat at large scales but scattered with local gentle slopes. Cloddy soil sticking on its wheels implies a greater cohesion of the lunar soil than encountered at other lunar landing sites. Further identification results indicate that the regolith resembles dry sand and sandy loam on Earth in bearing properties, demonstrating greater bearing strength than that identified during the Apollo missions. In sharp contrast to the sparsity of rocks along the traverse route, small fresh craters with unilateral moldable ejecta are abundant, and some of them contain high-reflectance materials at the bottom, suggestive of secondary impact events. These findings hint at notable differences in the surface geology between the lunar farside and nearside. Experience gained with Yutu-2 improves the understanding of the farside of the Moon, which, in return, may lead to locomotion with improved efficiency and larger range.

[Gut microbiome composition in pre-adolescent children with different meat consumption patterns]

OBJECTIVE

To compare the composition of gut microbiome in pre-adolescent children with different meat consumption patterns.

METHODS

This study was conducted among 44 healthy school-age children (age range 8-10 years) in Shenzhen. According to the monthly intake frequency ratio of white meat and red meat, the children were divided into red-meat group (n=15), balanced group (n=16) and white-meat group (n=13). The Food Frequency Questionnaire (FFQ) was used to investigate the children's diet, and samples of morning feces were collected to study the gut microbiome. The fecal DNA was extracted and amplified, and the composition of the intestinal microbiome of the children was analyzed using Illumina Miseq high-throughput sequencing.

RESULTS

The children in red meat and white meat groups showed significantly lower abundance and diversity of gut microbiota than those with a balanced diet (P < 0.05). LEfSe analysis of the genus in the fecal samples showed that Escherichia-Shigella, Coprobacillus and Peptoniphilus were enriched in red-meat group and Holdemanella was enriched in the white-meat group as compared with the balanced group. In the samples of the balanced group, 31 and 25 genus (such as Laurespirillum and Rumenococcus) were significantly enriched as compared with the samples of the red-meat group and the white-meat group, respectively. Prediction of the gut microbiota KEGG pathway using PICRUSt2 suggested that compared with that in the balanced group, the gut microbiota in red-meat group had significant activation of the pathways involving lipopolysaccharide biosynthesis (P < 0.01), arachidonic acid metabolism (P < 0.01), thyroid hormone synthesis (P < 0.001), and carbohydrate digestion and absorption (P < 0.05). But compared with the white-meat group, the red-meat group showed only significant activation of the pathways of arachidonic acid metabolism (P < 0.05) and thyroid hormone synthesis (P < 0.05).

CONCLUSION

The preference of red meat and white meat consumption may significantly reduce the abundance and diversity of gut microbiota in pre-adolescent children. A red meat-rich diet may cause enrichment of Escherichia-Shigella and significant activation of lipopolysaccharide biosynthesis pathway, suggesting the potential benefit of a balanced diet for pre-adolescent children.

Synthesis, surface activities and aggregation properties of asymmetric Gemini surfactants

A series of Gemini surfactants with an asymmetric structure (PKO 15-3(OH)-n; n = 12, 14 and 16) were synthesized through a simple two-step reaction consisting of a ring-opening reaction followed by a quaternization reaction. The surface tension measurements indicated that the surface activities of PKO 15-3(OH)-n were higher than those of traditional single-chain and symmetrical Gemini surfactants. The thermodynamic parameters obtained from electrical conductivity measurements showed that the micellization processes of PKO 15-3(OH)-n were spontaneous and entropy-driven. Transmission electron microscopy and dynamic light scattering measurements confirmed that PKO 15-3(OH)-n molecules with a higher asymmetric degree could form vesicles, in which surfactant molecules were interdigitated side-by-side in the vesicle membrane. The obtained results are not in accordance with those calculated from the critical packing theory, which can further complement the theory.

Trim28 acts as restriction factor of prototype foamy virus replication by modulating H3K9me3 marks and destabilizing the viral transactivator Tas

Background

Prototype foamy virus (PFV) is nonpathogenic complex retroviruses that express a transcriptional transactivator Tas, which is essential for the activity of viral long terminal repeat (LTR) promoter and internal promoter (IP). Tripartite motif-containing protein 28 (Trim28) is well known as a scaffold protein normally enriched in gene promoter region to repress transcription. We sought to determine if whether Trim28 could be enriched in PFV promoter region to participate the establishment of PFV latency infection.

Results

In this study, we show that Trim28 restricts Tas-dependent transactivation activity of PFV promoter and negatively regulates PFV replication. Trim28 was found to be enriched in LTR instead of IP promoter regions of PFV genome and contribute to the maintenance of histone H3K9me3 marks on the LTR promoter. Furthermore, Trim28 interacts with Tas and colocalizes with Tas in the nucleus. Besides, we found that Trim28, an E3 ubiquitin ligase, binds directly to and promotes Tas for ubiquitination and degradation. And the RBCC domain of Trim28 is required for the ubiquitination and degradation of Tas.

Conclusions

Collectively, our findings not only identify a host factor Trim28 negatively inhibits PFV replication by acting as transcriptional restriction factor enriched in viral LTR promoter through modulating H3K9me3 mark here, but also reveal that Trim28 mediated ubiquitin proteasome degradation of Tas as a mechanism underlying Trim28 restricts Tas-dependent transcription activity of PFV promoter and PFV replication. These findings provide new insights into the process of PFV latency establishment.

Graphical Abstract

Giant Biquadratic Exchange in 2D Magnets and Its Role in Stabilizing Ferromagnetism of NiCl_{2} Monolayers

Two-dimensional (2D) van der Waals (vdW) magnets provide an ideal platform for exploring, on the fundamental side, new microscopic mechanisms and for developing, on the technological side, ultracompact spintronic applications. So far, bilinear spin Hamiltonians have been commonly adopted to investigate the magnetic properties of 2D magnets, neglecting higher order magnetic interactions. However, we here provide quantitative evidence of giant biquadratic exchange interactions in monolayer NiX_{2} (X=Cl, Br and I), by combining first-principles calculations and the newly developed machine learning method for constructing Hamiltonian. Interestingly, we show that the ferromagnetic ground state within NiCl_{2} single layers cannot be explained by means of the bilinear Heisenberg Hamiltonian; rather, the nearest-neighbor biquadratic interaction is found to be crucial. Furthermore, using a three-orbitals Hubbard model, we propose that the giant biquadratic exchange interaction originates from large hopping between unoccupied and occupied orbitals on neighboring magnetic ions. On a general framework, our work suggests biquadratic exchange interactions to be important in 2D magnets with edge-shared octahedra.

Untargeted lipidomics analysis in women with intrahepatic cholestasis of pregnancy: a cross-sectional study

OBJECTIVE

To compare the plasma lipid profiles in women with normal pregnancies and those with mild or severe intrahepatic cholestasis of pregnancy (ICP). Our goal was to reveal lipidome-wide alterations in ICP and delve into the pathogenesis of ICP from a lipid metabolism perspective.

DESIGN

Cross-sectional study, including women with normal pregnancies, women with mild ICP and women with severe ICP.

SETTING

Gansu Provincial Hospital.

POPULATION

Women with ICP were recruited from October 2019 to March 2020 in Gansu, China.

METHODS

Untargeted lipidomics was used to analyse differentially expressed plasma lipids in controls, in women with mild ICP and in women with severe ICP (n = 30 per group). For lipidomics, liquid chromatography and Q-Exactive Plus Orbitrap mass spectrometry were performed.

MAIN OUTCOME MEASURES

Differentially expressed lipids.

RESULTS

Thirty-three lipids were differentially expressed in the severe and mild ICP groups, compared with the control group, and 20 of those were sphingolipids (ceramide, six species; sphingomyelin, 14 species). All differentially expressed sphingolipids in women with mild ICP were also differentially expressed in women with severe ICP; the fold change and significance of the differential expression were positively correlated with disease severity.

CONCLUSIONS

We systematically characterized the lipidome-wide alterations in mild and severe ICP groups. The results indicated a link between ICP and disordered sphingolipid homeostasis.

TWEETABLE ABSTRACT

Abnormal sphingolipid metabolism is involved in the pathogenesis of ICP.

Moving Chemistry from Bench to Market: An Introduction to the Agricultural and Food Chemistry Technical Program at the 260th American Chemical Society Fall 2020 Virtual Meeting & Expo

This is the second special issue of the Journal of Agricultural and Food Chemistry (JAFC) that reviews the Agricultural and Food Chemistry Division (AGFD) technical program from a national meeting of the American Chemical Society (ACS). The 260th meeting was virtually held on August 17-20, 2020 as a result of the COVID-19 pandemic. Although it was the first-ever all online meeting in ACS history, a total of 311 abstracts were submitted to the AGFD technical program for oral and poster presentations and 34 technical sessions were held in 22 symposia, which covered a broad range of food and agricultural topics. The very first virtual ACS meeting was successful with the high quality of presentations, the number of online audiences, and seamless technology.

Taking Advantage of the Renewable Forest Bioresource Turpentine to Prepare α,β-Unsaturated Compounds as Highly Efficient Fungicidal Candidates

In a continuous study on the high-value-added exploration of a renewable forest bioresource turpentine in modern organic agriculture, two series of α-pinene derivatives containing amide and α,β-unsaturated ketone pharmacophores were prepared. Through an in-depth fungicidal activity study, the title compounds presented excellent inhibitory activity against common crop fungi, especially Sclerotinia sclerotiorum, and the notable EC₅₀ values of α,β-unsaturated compounds 3u (funan containing) and 3v (thiophene containing) were 1.657 and 1.749 μg/mL, respectively. Further physiological and biochemical studies on S. sclerotiorum revealed that compounds 3u and 3v reduced the ergosterol content in the cell membrane and increased the permeability of the cell membrane. In combination with their effect on mycelial morphology, the title compounds might have inhibitory effects on the biosynthesis of ergosterol, which is a paramount component of the target cell membrane. Moreover, quantitative structure-activity relationship (QSAR) and SAR studies revealed that the charge distribution of α,β-unsaturated carbonyl ketone derivatives played an important role in the observed fungicidal activity. In summary, this study highlights the design and development of novel high-efficacy turpentine-based antifungal agents.

Review on natural killer /T-cell lymphoma

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is strongly associated with Epstein-Barr virus (EBV) and has a high prevalence in Asian and in Central and South America. About 85% of ENKTLs derive from NK cells and 15% from T-cells. Various factors have been implicated in the development of ENKTL. Molecular pathogenesis of NK/T-cell lymphomas include mutations of genes, involving in the Janus Kinase (JAK)/ signal transducer and activator of transcription (STAT) pathway, RNA helicase family, epigenetic regulation, and tumor suppression. The relationship between ENKTL and human leukocyte antigen (HLA) has been demonstrated. Radiotherapy (RT) plays a key role in the first-line treatment of early-stage. In stage III/IV diseases, non-anthracycline-regimens-containing L-asparaginase are recommended. Although clinical remission after L-asparaginase-based combination therapy has been achieved in the majority of patients with advanced-stage or relapsed/refractory(r/r) ENKL, the long-term overall survival is still poor. Recently, immunotherapy and new therapeutic targets have gained much attention. In this article, we discuss the pathogenesis, diagnosis, prognostic models and management options of ENKTL. This article is protected by copyright. All rights reserved.

[Outcome of radiotherapy for low-risk early-stage patients with extranodal NK/T-cell lymphoma, nasal-type]

Objective: To evaluate the prognosis and determine the failure patterns after radiotherapy for low-risk early-stage patients with extranodal NK/T-cell lymphoma, nasal-type (ENKTCL). Methods: A total of 557 patients from 2000-2015 with low-risk early-stage ENKTCL who received radiotherapy (RT) with or without chemotherapy (CT) from China Lymphoma Collaborative Group were retrospectively reviewed. Among them, 427 patients received combined modality therapy, whereas 130 patients received RT alone. Survivals were calculated by Kaplan-Meier method and compared with Log-rank test. Overall survival (OS) was compared with age and sex-matched general Chinese population using expected survival and standardized mortality ratio (SMR). Cox stepwise regression model was used for multivariate analysis. Results: The 5-year OS and progression-free survival (PFS) were 87.2% and 77.2%. The SMR was 3.59 (P<0.001) at 1 year after treatment, whereas it was 1.50 at 4 years after treatment, without significant difference between ENKTCL group and country-matched general population (P=0.146). Compared with RT alone, CMT did not result in significantly superior 5-year OS (87.0% vs 87.4%, P=0.961) or PFS (76.1% vs 80.7%, P=0.129). Local failure (11.5%, 64/557) and distant failure (10.8%, 60/557) were the main failure modes, while regional failure was rare (2.9%, 16/557). The 5-year locoregional control rate (LRC) was 87.2% for the whole group, with 89.5% for ≥50 Gy versus 73.7% for <50 Gy (P<0.001). Radiotherapy dose was an independent factor affecting LRC(P<0.05). Conclusions: Radiotherapy achieves a favorable prognosis in patients with low-risk early-stage ENKTCL. The incidence of either locoregional or distant failure is low. Radiation dose still is an important prognostic factor for LRC.

Probing Gluon Spin-Momentum Correlations in Transversely Polarized Protons through Midrapidity Isolated Direct Photons in p^{↑}+p Collisions at sqrt[s]=200 GeV

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200  GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

[Epidemiological characteristics of close contacts of COVID-19 cases and infection-related risk factors in Beijing]

Objective: To analyze the epidemiological characteristics of close contacts of COVID-19 cases and infection-related risk factors in Beijing and provide evidences for COVID-19 prevention and control. Methods: A total of 20 681 close contacts of COVID-19 cases, who had exposures during January 6, 2020 to February 15, 2021, were traced in Beijing. The information about their demographic characteristics, exposure history, and quarantine outcomes were collected and analyzed with descriptive statistics. The logistic regression analysis was used to identify the risk factors for COVID-19. Results: The infection rate SARS-CoV-2 in close contacts was 2.16% (447/20 681). The age M(P₂₅, P₇₅) was 35 (27, 49) years. The majority of the close contacts were aged 20-59 years, accounting for 81.77% (16 912/20 681). Centralized isolation was the major type of medical observation, accounting for 82.15% (16 989/20 681). Among the exposure types, working and studying in the same room (16.06%, 3 322/20 681), sharing same transport vehicle (12.88%, 2 664/20 681), performing diagnosis and treatment nursing (7.80%,1 612/20 681), and living together (7.23%,1 495/20 681), accounting for 43.96% (9 093/20 681). The index cases included staff (19.34%, 3 999/20 681), the unemployed (17.34%, 3 586/20 681), people engaged in business service (13.85%, 2 864/20 681), people engaged in food service (10.77%, 2 228/20 681), their close contacts accounted for 61.30% (12 677/20 681). Multivariate logistic regression analysis showed that compared with other types of exposure, the risk factors for infection were having meal together (OR=3.96, 95%CI: 2.30-6.83) and living together (OR=6.41, 95%CI:4.48-9.17); Compared with the other occupations, the index case being engaged in food service (OR=3.06, 95%CI:1.29-7.25) and teacher (OR=4.94, 95%CI:1.43-17.08) were risk factors for the infection. Conclusions: The main environmental exposure types of SARS-CoV-2 infection in close contacts were having meal together and living together. Contact with the index case being engaged in food service and teacher increased the risk for COVID-19. Comprehensive prevention and control measures such as centralized isolation and vaccination should be continued.

Biological modulations to facilitate graft healing in anterior cruciate ligament reconstruction (ACLR), when and where to apply? A systematic review

Background

When and where to apply the biological modulations is effective to promote healing in the anterior cruciate ligament (ACL) reconstruction remains unclear.

Purpose

To perform a systematic review of preclinical animal studies on biological modulation in anterior cruciate ligament reconstruction (ACLR) concerning the time and site of delivery.

Study design

Systematic review of controlled laboratory studies.

Methods

PubMed, Ovid, and Scopus were searched until December 2020 using a combination of keywords and their synonym to retrieve all animal studies about biological modulation in ACLR. Studies that assessed mechanical strength after ACLR and compared with negative control were included. The methodological quality of animal studies was evaluated.

Results

33 studies were included in this review and the majority reported mechanical strength improvement. 79 ​% of studies applied the biological modulations intra-operatively with different delivery systems used. For 21 ​% of post-operative delivery studies, intermittent delivery was tried. 21 of the included studies directly applied the biological modulations in the bone tunnels, 5 studies applied intra-articularly while 7 studies applied both in the bone tunnels and intra-articular part. Biological modulations applied intra-operatively and those applied in both parts showed better mechanical strength increase. A shift of the failure mode of pull-out from the bone tunnel in the early healing phase, to mid-substance rupture in the later phase was observed in most studies.

Conclusion

The improvement of the mechanical strength depends on how the biological modulations (delivery phase, delivery site, delivery form) are applied. The intra-operative delivery showed an overall higher mechanical strength increase and bone tunnel only delivery or intra-articular and bone tunnel both delivery are preferred than intra-articular only delivery. In addition, intra-articular and bone tunnel both delivery can have better mechanical strength increase for a long follow-up time. Thus, intra-operative application with a carrier to control release rate in both parts should be recommended. Further studies are needed to achieve a better healing outcome and more attention should be given to the intra-articular remodeling of the graft along with the tendon bone healing to increase the final mechanical strength.

The Translational potential of this article

Here, a systematic review of preclinical evidence of the time, site and the method the biological modulations being applied for ACLR to improve the graft healing would be performed. After reviewing the available studies, a choice of when and where to apply the biological modulations can achieve better mechanical strength after ACLR can be obtained. It provides evidence for both researchers and clinicians to decide when and where to apply the biological modulations can achieve their best effectiveness for ACLR before implementing. Promoting graft healing with targeted time and targeted site may reduce the risk of graft failure, safeguard return to sport.

Combined tumor-associated macrophages biomarker predicting extremely poor outcome of patients with primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is an aggressive and rare malignancy with poor prognosis. However, there are no reliable prognostic biomarkers for PCNSL in clinical practice. Here, we aimed to identify a reliable prognostic biomarker for predicting the survival of PCNSL patients. In this study, multiplex immunofluorescence and digital imaging analysis were used to characterize tumor-associated macrophages (TAMs) immunophenotypes and the expression of programmed cell death ligand 1 on TAMs, with regard to prognosis from diagnostic tumor tissue samples of 59 PCNSL patients. We found that the M2-to-M1 ratio was a more reliable prognostic biomarker for PCNSL than M1-like or M2-like macrophage infiltration. In addition, the combination of programmed death-ligand 1 (PD-L1) expression on TAMs and the M2-to-M1 ratio in PCNSL demonstrated improved performance in prognostic discrimination than PD-L1-positive TAMs or M2-to-M1 ratio. To validate the prognostic significance of the combined TAMs associated biomarkers, they were integrated into the International Extranodal Lymphoma Study Group (IELSG) index and termed as IELSG-M index. Kaplan-Meier plots showed that the IELSG-M index could discriminate patients into low-, intermediate- or high-risk subgroups, better than IELSG, in terms of prognosis. The areas under the receiver operating characteristic curves of IELSG-M was 0.844 for overall survival; superior to the IELSG model (0.580). Taken together, this study's findings showed that the combination of PD-L1 on TAMs and the M2-to-M1 ratio could be strong prognostic predictive biomarkers for PCNSL and the IELSG-M index had improved prognostic significance than the IELSG index.