Publications by authors named "Lei Tao"

567 Publications

Intrinsically Honeycomb-Patterned Hydrogenated Graphene.

Small 2021 Nov 30:e2102687. Epub 2021 Nov 30.

Institute of Physics and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China.

Since the advent of graphene ushered the era of 2D materials, many forms of hydrogenated graphene have been reported, exhibiting diverse properties ranging from a tunable bandgap to ferromagnetic ordering. Patterned hydrogenated graphene with micron-scale patterns has been fabricated by lithographic means. Here, successful millimeter-scale synthesis of an intrinsically honeycomb-patterned form of hydrogenated graphene on Ru(0001) by epitaxial growth followed by hydrogenation is reported. Combining scanning tunneling microscopy observations with density-functional-theory (DFT) calculations, it is revealed that an atomic-hydrogen layer intercalates between graphene and Ru(0001). The result is a hydrogen honeycomb structure that serves as a template for the final hydrogenation, which converts the graphene into graphane only over the template, yielding honeycomb-patterned hydrogenated graphene (HPHG). In effect, HPHG is a form of patterned graphane. DFT calculations find that the unhydrogenated graphene regions embedded in the patterned graphane exhibit spin-polarized edge states. This type of growth mechanism provides a new pathway for the fabrication of intrinsically patterned graphene-based materials.
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http://dx.doi.org/10.1002/smll.202102687DOI Listing
November 2021

Visualization Experimental Study on Well Spacing Optimization of SAGD with a Combination of Vertical and Horizontal Wells.

ACS Omega 2021 Nov 27;6(44):30050-30060. Epub 2021 Oct 27.

Shandong Ruiheng Xingyu Petroleum Technology Development Co., Ltd, Qingdao 266500, China.

For oil sand reservoirs, the steam-assisted gravity drainage (SAGD) technique is one of the most efficient thermal recovery technologies. However, the high oil viscosity and the severe heat loss seriously affect the production effect of SAGD in developing thin oil sand reservoirs by the traditional SAGD technology. Therefore, it is essential to improve the SAGD technology to enhance the recovery of the thin oil sand reservoir. In this paper, SAGD with a combination of vertical and horizontal well (VH-SAGD) technology was adopted, and the influence of different well spacings (horizontal distance between vertical steam injection wells and horizontal production wells) on the development of steam chambers was investigated. By the similarity criterion, the experimental parameters were obtained. After that, an improved 2D visualization physical model was designed with 9 × 9 high-precision thermocouples installed inside the device to monitor the real-time temperature. This experimental physical model can not only accurately capture the temperature distribution but also display the continuous change process of the chamber inside the model by the visible window. Finally, different well spacing cases (10, 15, and 20 cm) were tested to observe the development of the steam chamber and analyze the production data. Both the temperature distribution and visual window showed that the steam chamber has four obvious stages, and reasonable well spacing can promote the development of the steam chamber. When the well spacing is relatively small, the unswept area of the cold oil on both sides is large, and the area of the steam chamber overlaps more. When the well spacing is relatively moderate, the steam chamber is the most complete and the recovery factor is the highest. When the well spacing is relatively large, although the unswept area of the cold oil on both sides is small, the middle cold oil area is larger than the previous two groups. Therefore, the best well spacing for oil sand reservoirs of about 15 m thickness is 15-20 m, where the VH-SAGD method has a better displacement effect and higher oil recovery. The experimental conclusions can provide theoretical support for the production of thin oil sand reservoirs.
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http://dx.doi.org/10.1021/acsomega.1c04737DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8582263PMC
November 2021

A new open-path eddy covariance method for nitrous oxide and other trace gases that minimizes temperature corrections.

Glob Chang Biol 2021 Nov 10. Epub 2021 Nov 10.

Department of Civil and Environmental Engineering, Princeton University, Princeton, New Jersey, USA.

Low-power, open-path gas sensors enable eddy covariance (EC) flux measurements in remote areas without line power. However, open-path flux measurements are sensitive to fluctuations in air temperature, pressure, and humidity. Laser-based, open-path sensors with the needed sensitivity for trace gases like methane (CH ) and nitrous oxide (N O) are impacted by additional spectroscopic effects. Corrections for these effects, especially those related to temperature fluctuations, often exceed the flux of gases, leading to large uncertainties in the associated fluxes. For example, the density and spectroscopic corrections arising from temperature fluctuations can be one or two orders of magnitude greater than background N O fluxes. Consequently, measuring background fluxes with laser-based, open-path sensors is extremely challenging, particularly for N O and gases with similar high-precision requirements. We demonstrate a new laser-based, open-path N O sensor and a general approach applicable to other gases that minimizes temperature-related corrections for EC flux measurements. The method identifies absorption lines with spectroscopic effects in the opposite direction of density effects from temperature and, thus, density and spectroscopic effects nearly cancel one another. The new open-path N O sensor was tested at a corn (Zea mays L.) field in Southwestern Michigan, United States. The sensor had an optimal precision of 0.1 ppbv at 10 Hz and power consumption of 50 W. Field trials showed that temperature-related corrections were 6% of density corrections, reducing EC random errors by 20-fold compared to previously examined lines. Measured open-path N O EC fluxes showed excellent agreement with those made with static chambers (m = 1.0 ± 0.3; r  = .96). More generally, we identified absorption lines for CO and CH  flux measurements that can reduce the temperature-related corrections by 10-100 times compared to existing open-path sensors. The proposed method provides a new direction for future open-path sensors, facilitating the expansion of accurate EC flux measurements.
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http://dx.doi.org/10.1111/gcb.15986DOI Listing
November 2021

Association Between Infections and Risk of Ankylosing Spondylitis: A Systematic Review and Meta-Analysis.

Front Immunol 2021 22;12:768741. Epub 2021 Oct 22.

School of Public Health, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, China.

Background: Previous literature on the association between infections and the risk of developing ankylosing spondylitis (AS) presented controversial results. This meta-analysis aimed to quantitatively investigate the effect of infections on the risk of AS.

Methods: We searched the PubMed, Embase, and Web of Science databases until March 26, 2021 for analytical epidemiological studies on the association between infections and the risk of AS. Fixed or random effect models were used to calculate total risk estimates based on study heterogeneity. Subgroup analysis, and sensitivity analysis were also performed. Publication bias was estimated using funnel plots and Begg's test.

Results: Six case-control articles (n=1,296,239) and seven cohort articles (n=7,618,524) were incorporated into our meta-analysis. The pooled odds ratio (OR) from these case-control studies showed that infections were associated with an increased risk of AS (OR=1.46, 95% confidence interval [CI], 1.23-1.73), and the pooled relative risk (RR) from the cohort studies showed the same findings (RR=1.35, 95% CI, 1.12-1.63). Subgroup analysis showed that infections in participants with unadjusted comorbidities (OR=1.66, 95% CI, 1.35-2.03), other types of infection (OR=1.40, 95% CI, 1.15-1.70), and infection of the immune system (OR=1.46, 95% CI, 1.42-1.49) were associated with the risk of AS in case-control studies. In cohort studies, infections with adjusted comorbidities (RR=1.39, 95% CI, 1.15-1.68), viral infection (RR=1.43, 95% CI, 1.22-1.66), other types of infection (RR=1.44, 95% CI, 1.12-1.86), and other sites of infection (RR=1.36, 95% CI, 1.11-1.67) were associated with an increased risk of AS.

Conclusions: The findings of this meta-analysis confirm that infections significantly increase the risks of AS. This is helpful in providing an essential basis for the prevention of AS the avoidance of infections.
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http://dx.doi.org/10.3389/fimmu.2021.768741DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8569302PMC
October 2021

T cell exhaustion drives osteosarcoma pathogenesis.

Ann Transl Med 2021 Sep;9(18):1447

Department of Geriatrics, the Fourth Affiliated Hospital of China Medical University, Shenyang, China.

Background: Osteosarcoma (OS) is a rare cancer with a bimodal age distribution that peaks in children and young adults. It has been shown that the expression of programmed cell death protein 1 (PD-1) and programmed death ligand-1 (PD-L1) on tumor-infiltrating immune cells negatively correlates with prognosis of OS patients. However, a comprehensive assessment of the tumor-infiltrating immune cells in OS and their function has not been performed.

Methods: CD8 T cells were isolated from biopsy tissue samples collected from OS patients and control subjects. Mass cytometry, Treg suppression assay, mixed lymphocyte reaction assay, and effector T cell functional assay were performed to analyze the function of tumor-infiltrating T cells. A xenograft metastasis model was established in BALB/c nude mice.

Results: Macrophages and CD3 T cells comprised most of the tumor-infiltrating immune cells in OS, with a disproportionately higher number of helper CD4 T cells than effector CD8 T cells. Whereas the tumor-infiltrating regulatory T cells were functionally intact, the CD8 T cells showed increased expression of the immune checkpoint receptor (ICR) PD-1 and T cell immunoglobulin and mucin-domain containing 3 (TIM3) and were functionally inactive. TIM3 blockade using a monoclonal antibody restored the T cell alloreactive function of the CD8 T cells . TIM3 blockade in a xenograft model of OS impaired tumor growth . TIM3 blockade decreased the number of tumor-infiltrating CD4 T cells while increasing the numbers and functional activation of tumor-infiltrating CD8 T cells .

Conclusions: These results highlight that TIM3 blockade might be a viable therapeutic option and should be tested in additional preclinical models.
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http://dx.doi.org/10.21037/atm-21-3928DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8506720PMC
September 2021

Risk Factors for Generalization in Patients with Ocular Myasthenia Gravis: A Multicenter Retrospective Cohort Study.

Neurol Ther 2021 Nov 2. Epub 2021 Nov 2.

Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, China.

Introduction: Many patients with ocular myasthenia gravis (OMG) progress to generalized disease within the first 2 years of the onset of ocular symptoms. Several retrospective studies have identified risk factors associated with generalization, however these studies included patients on immunosuppression therapy or those undergoing thymectomy, which may reduce the generalization risk. In this study we explored the risk factors for generalization in non-immunosuppressed and non-thymectomized patients with OMG.

Methods: Data from patients with OMG treated at seven tertiary hospitals in China were retrospectively reviewed. Clinical characteristics, including sex, age at onset, symptoms at onset, comorbid autoimmune diseases, neostigmine test response, repetitive nerve stimulation (RNS) findings, presence of serum anti-acetylcholine receptor antibody (AChR-Ab), and thymic status based on radiological and pathological studies, were collected. The main outcome measure was disease generalization. The follow-up period was defined as the date of ocular symptom onset to the date of confirmation of generalization or immunotherapy initiation, or last follow-up (defined as 60 months). The Cox proportional hazards model was used to assess the risk factors for generalization.

Results: Overall, 572 patients (269 women) were eligible for inclusion in the analysis, of whom 144 developed generalization. The mean (standard deviation) onset age was 45.5 (19.8) years, and the median (interquartile range) follow-up period was 14.5 (7.0-47.3) months. Multivariable Cox regression analysis demonstrated that both early-onset (adjusted hazard ratio [aHR] 5.34; 95% confidence interval [CI] 1.64-17.36; p = 0.005) and late-onset (aHR 7.18; 95% CI 2.22-23.27; p = 0.001) in adulthood, abnormal RNS findings (aHR 3.01; 95% CI 1.97-4.61; p < 0.001), seropositivity for AChR-Ab (aHR 2.58; 95% CI 1.26-5.26; p = 0.01), and thymoma (aHR 1.62; 95% CI 1.05-2.49; p = 0.03) were independently associated with increased risk of generalization.

Conclusion: The risk of generalization increased significantly in patients with adult-onset OMG, abnormal RNS findings, seropositivity for AChR-Ab, and thymoma, suggesting that these risk factors may predict OMG generalization.
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http://dx.doi.org/10.1007/s40120-021-00292-xDOI Listing
November 2021

The β3/5 Integrin-MMP9 Axis Regulates Pulmonary Inflammatory Response and Endothelial Leakage in Acute Lung Injury.

J Inflamm Res 2021 5;14:5079-5094. Epub 2021 Oct 5.

Department of Anesthesiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, People's Republic of China.

Background: Acute lung injury (ALI) is a severe respiratory disease with high rates of morbidity and mortality. Many mediators regarding endogenous or exogenous are involved in the pathophysiology of ALI. Here, we have uncovered the involvement of integrins and matrix metalloproteinases, as critical determinants of excessive inflammation and endothelial permeability, in the regulation of ALI.

Methods: Inflammatory cytokines were measured by quantitative real-time PCR for mRNA levels and ELISA for secretion levels. Endothelial permeability assay was detected by the passage of rhodamine B isothiocyanate-dextran. Mice lung permeability was assayed by Evans blue albumin (EBA). Western blot was used for protein level measurements. The intracellular reactive oxygen species (ROS) were evaluated using a cell-permeable probe, DCFH-DA. Intratracheal injection of lipopolysaccharide (LPS) into mice was conducted to establish the lung injury model.

Results: Exogenous MMP-9 significantly aggravated the inflammatory response and permeability in mouse pulmonary microvascular endothelial cells (PMVECs) treated by LPS, whereas knockdown of MMP-9 exhibited the opposite phenotypes. Knockdown of integrin β3 or β5 in LPS-treated PMVECs significantly downregulated MMP-9 expression and decreased inflammatory response and permeability in the presence or absence of exogenous MMP-9. Additionally, the interaction of MMP-9 and integrin β5 was impaired by a ROS scavenger, which further decreased the pro-inflammatory cytokines production and endothelial leakage in PMVECs subjected to co-treatment (LPS with exogenous MMP-9). In vivo studies, exogenous MMP-9 treatment or knockdown β3 integrin significantly decreased survival in ALI mice. Notably, knockdown of β5 integrin alone had no remarkable effect on survival, but which combined with anti-MMP-9 treatment significantly improved the survival by ameliorating excessive lung inflammation and permeability in ALI mice.

Conclusion: These findings support the β3/5 integrin-MMP-9 axis as an endogenous signal that could play a pivotal role in regulating inflammatory response and alveolar-capillary permeability in ALI.
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http://dx.doi.org/10.2147/JIR.S331939DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8502060PMC
October 2021

Benchmarking Machine Learning Models for Polymer Informatics: An Example of Glass Transition Temperature.

J Chem Inf Model 2021 11 18;61(11):5395-5413. Epub 2021 Oct 18.

Department of Mechanical Engineering, University of Connecticut, Storrs, Connecticut 06269, United States.

In the field of polymer informatics, utilizing machine learning (ML) techniques to evaluate the glass transition temperature and other properties of polymers has attracted extensive attention. This data-centric approach is much more efficient and practical than the laborious experimental measurements when encountered a daunting number of polymer structures. Various ML models are demonstrated to perform well for prediction. Nevertheless, they are trained on different data sets, using different structure representations, and based on different feature engineering methods. Thus, the critical question arises on selecting a proper ML model to better handle the prediction with generalization ability. To provide a fair comparison of different ML techniques and examine the key factors that affect the model performance, we carry out a systematic benchmark study by compiling 79 different ML models and training them on a large and diverse data set. The three major components in setting up an ML model are structure representations, feature representations, and ML algorithms. In terms of polymer structure representation, we consider the polymer monomer, repeat unit, and oligomer with longer chain structure. Based on that feature, representation is calculated, including Morgan fingerprinting with or without substructure frequency, RDKit descriptors, molecular embedding, molecular graph, etc. Afterward, the obtained feature input is trained using different ML algorithms, such as deep neural networks, convolutional neural networks, random forest, support vector machine, LASSO regression, and Gaussian process regression. We evaluate the performance of these ML models using a holdout test set and an extra unlabeled data set from high-throughput molecular dynamics simulation. The ML model's generalization ability on an unlabeled data set is especially focused, and the model's sensitivity to topology and the molecular weight of polymers is also taken into consideration. This benchmark study provides not only a guideline for the prediction task but also a useful reference for other polymer informatics tasks.
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http://dx.doi.org/10.1021/acs.jcim.1c01031DOI Listing
November 2021

Matrine suppresses lung cancer metastasis targeting M2-like tumour-associated-macrophages polarization.

Am J Cancer Res 2021 15;11(9):4308-4328. Epub 2021 Sep 15.

Putuo Hospital, Shanghai University of Traditional Chinese Medicine Shanghai 200062, China.

Metastasis is the primary cause of death in lung cancer, one of the most prevalent and deadly neoplasms. The tumour-associated macrophages (TAMs) are crucial mediators to induce epithelial-mesenchymal transition (EMT) and promote lung metastasis release of the cytokines. Matrine, a naturally occurring alkaloid, has been found with a variety of pharmacological effects, such as anti-cancer. In this study, an co-culture cell systems and a Lewis-bearing mouse model were employed to assay the potential effects of matrine on macrophages polarization, and its regulatory effects on EMT of Lewis lung cancer cells (LLCs). Our results clearly demonstrated that matrine inhibited M2-like RAW264.7 polarization, reducing the production of anti-inflammatory cytokines (IL-4, IL-10, and Arg-1), and M2 surface markers (CD206) were induced by LLCs mTOR/PI3k/Akt signaling pathway, while it had no significant effect on M1 macrophages polarization. assays suggested that matrine partially blocked the metastasis of LLCs, and inhibited EMT induced by M2-like macrophages, which was evidenced by up-regulating the expression of E-cadherin and down-regulating the expression of N-cadherin, vimentin, and Snail. studies revealed that matrine decreased the ratio of CD206/F4/80, promoted the expression of CD4 and CD8 T cells, and inhibited the expression of Th2 in tumor and spleen tissues. Cell co-culture experiments revealed that Matrine promoted T-cell proliferation, which was impaired by tumour-derived CD11b myeloid cells. Collectively, our findings suggest that suppression of M2-like macrophages polarization of TAMs is a potential mechanism underlying the anti-metastasis effects of matrine in lung cancer.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8493404PMC
September 2021

A Specific Predicting Model for Screening Skip Metastasis From Patients With Negative Central Lymph Nodes Metastasis in Papillary Thyroid Cancer.

Front Endocrinol (Lausanne) 2021 30;12:743900. Epub 2021 Sep 30.

Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Skip metastasis is a specific type of papillary thyroid cancer lymph node metastasis (LNM). The present study aimed to clarify the typical clinical characteristics of skip metastasis and optimize the prediction model, so as to provide a more individual treatment mode for skip metastasis. We retrospectively analyzed 1075 PTC patients with different lymph node metastasis statuses from two clinical centers. Comparisons have been made between patients with skip metastasis and other types of LNM. Univariate and multivariate analyses were performed to detect the risk factors for skip metastasis with negative LNM, and a nomogram for predicting skip metastasis was established. The rate of skip metastasis was 3.4% (37/1075). Compared with other types of LNM, significant differences showed in tumor size, upper portion location, thyroid capsular invasion, and ipsilateral nodular goiter with the central lymph node metastasis (CLNM) group, and in age and gender with the lateral lymph node metastasis (LLNM) group. Four variables were found to be significantly associated with skip metastasis and were used to construct the model: thyroid capsular invasion, multifocality, tumor size > 1 cm, and upper portion. The nomogram had good discrimination with a concordance index of 0.886 (95% confidence interval [CI], 0.823 to 0.948). In conclusion, the significant differences between skip metastasis and other types of LNM indicated that the lymph node drainage pathway of skip metastasis is different from either CLNM or LLNM. Furthermore, we established a nomogram for predicting risk of skip metastasis, which was able to effectively predict the potential risk of skip metastasis in patients without preoperative LNM clue.
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http://dx.doi.org/10.3389/fendo.2021.743900DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8515125PMC
September 2021

Catalpol alleviates Ang II-induced renal injury through NF/κB pathway and TGF-β1/Smads pathway.

J Cardiovasc Pharmacol 2021 Oct 4. Epub 2021 Oct 4.

Department of Cardiology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, 250014, P.R. China Department of Traumatic Orthopaedics, The Third Affiliated Hospital of Shandong First Medical University (Affiliated Hospital of Shandong Academy of Medical Sciences), Jinan, Shandong, 250031, P.R. China Department of science and technology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, 250014, P.R. China Department of Nephrology, The Third Affiliated Hospital of Shandong First Medical University (Affiliated Hospital of Shandong Academy of Medical Sciences), Jinan, Shandong, 250031, P.R. China.

Abstract: Catalpol is an iridoid glycoside obtained from Rehmannia glutinosa, which in previous studies showed various pharmacological properties, including anti-inflammatory, antioxidant, antidiabetic, antitumor and dopaminergic neurons protecting effects. Here, we examined the effect of catalpol on AngII-induced renal injury induced by angiotensin II (AngII), and further to explore its latent molecular mechanisms. We used an in vivo model of AngII-induced renal injury mice, catalpol (25, 50, and 100 mg/kg) was administered for 28 days. Mouse glomerular mesangial cells (SV40 MES 13), rat kidney interstitial fibroblasts cells (NRK-49F), and human proximal tubular epithelial cells (HK-2) were induced by AngII (10 µM) in the presence or absence of catalpol (1, 5, and 10 µM) and incubated for 48 h in vitro. In our study, PAS and masson staining of renal tissue showed that catalpol reduced AngII-induced renal injury in a concentration-dependent manner. The positive expressions of Collagen IV and TGF-β1 were observed to decrease sharply after catalpol treatment. In renal tissue, the levels of pro-inflammatory cytokines TNF-α and IL-6 were evidently decreased after catalpol intervention. Catalpol can relieve AngII-induced renal injury by inactivating NF/κB and TGF-β1/Smads signaling pathways. Therefore, catalpol may act as a potential drug to treat AngII-induced renal injury.
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http://dx.doi.org/10.1097/FJC.0000000000001148DOI Listing
October 2021

Thymectomy and Risk of Generalization in Patients with Ocular Myasthenia Gravis: A Multicenter Retrospective Cohort Study.

Neurotherapeutics 2021 Oct 8. Epub 2021 Oct 8.

Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, 569 XinSi Road, Xi'an, 710038, China.

This study aims to investigate the association between thymectomy and the risk of generalization in patients with ocular myasthenia gravis (MG). Data on patients with ocular MG from seven neurological centers in China were retrospectively reviewed. Ocular MG naïve to immunotherapy was categorized according to whether thymectomy was performed (thymectomized group vs. nonsurgical group). Patients in the thymectomized group all underwent surgery within 2 years since ocular symptom onset. The main outcome measure was the generalization. The follow-up period was defined from the date of ocular symptom onset to the date of generalization confirmation, immunotherapy initiation, or last follow-up (defined as 60 months). Of 519 eligible patients (mean [SD] age, 48.7 [15.2] years, 46.6% women), 31 (23.7%) of 131 generalized in the thymectomized group and 122 (31.4%) of 388 did in the nonsurgical group during a median follow-up of 19 months (IQR 8.0-50.0). Thymectomy was independently associated with reduced generalization risk (adjusted HR 0.41, 95% CI 0.25-0.66, P < 0.001). Multivariable stratified analysis also verified this association across the subgroups. Kaplan-Meier curves showed that the 5-year cumulative rate was significantly lower in the thymectomized group than in the nonsurgical group. To conclude, thymectomy may be considered effective in modifying the progression from ocular to generalized MG irrespective of thymoma.
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http://dx.doi.org/10.1007/s13311-021-01129-zDOI Listing
October 2021

Design of Entropy-Driven Polymers Resistant to Bacterial Attachment via Multicomponent Reactions.

J Am Chem Soc 2021 Oct 7;143(41):17250-17260. Epub 2021 Oct 7.

The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, People's Republic of China.

Nonbactericidal polymers that prevent bacterial attachment are important for public health, environmental protection, and avoiding the generation of superbugs. Here, inspired by the physical bactericidal process of carbon nanotubes and graphene derivatives, we develop nonbactericidal polymers resistant to bacterial attachment by using multicomponent reactions (MCRs) to introduce molecular "needles" (rigid aliphatic chains) and molecular "razors" (multicomponent structures) into polymer side chains. Computer simulation reveals the occurrence of spontaneous entropy-driven interactions between the bacterial bilayers and the "needles" and "razors" in polymer structures and provides guidance for the optimization of this type of polymers for enhanced resistibility to bacterial attachment. The blending of the optimized polymer with commercially available polyurethane produces a film with remarkably superior stability of the resistance to bacterial adhesion after wear compared with that of commercial mobile phone shells made by the Sharklet technology. This proof-of-concept study explores entropy-driven polymers resistant to bacterial attachment via a combination of MCRs, computer simulation, and polymer chemistry, paving the way for the design of nonbactericidal polymers to prevent bacterial contamination.
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http://dx.doi.org/10.1021/jacs.1c08332DOI Listing
October 2021

Direct C-H Thiolation for Selective Cross-Coupling of Arenes with Thiophenols via Aerobic Visible-Light Catalysis.

Org Lett 2021 Oct 5;23(20):8082-8087. Epub 2021 Oct 5.

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

An aerobic metal-free, visible-light-induced regioselective thiolation of phenols with thiophenols is reported. The cross-coupling protocol exhibits great functional group tolerance and high regioselectivity. Mechanistic studies reveal that the disulfide radical cation plays a crucial role in the visible-light catalysis of aerobic thiolation. Simply controlling the equivalent ratio of substrates enables the selective formation of sulfide or sulfoxide products with high activity in a one-pot reaction.
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http://dx.doi.org/10.1021/acs.orglett.1c03090DOI Listing
October 2021

Activity of Cu-Al-Oxo Extra-Framework Clusters for Selective Methane Oxidation on Cu-Exchanged Zeolites.

JACS Au 2021 Sep 14;1(9):1412-1421. Epub 2021 Jul 14.

Department of Chemistry and Catalysis Research Center, TU München, Lichtenbergstrasse 4, 85748 Garching, Germany.

Cu-zeolites are able to directly convert methane to methanol via a three-step process using O as oxidant. Among the different zeolite topologies, Cu-exchanged mordenite (MOR) shows the highest methanol yields, attributed to a preferential formation of active Cu-oxo species in its 8-MR pores. The presence of extra-framework or partially detached Al species entrained in the micropores of MOR leads to the formation of nearly homotopic redox active Cu-Al-oxo nanoclusters with the ability to activate CH. Studies of the activity of these sites together with characterization by Al NMR and IR spectroscopy leads to the conclusion that the active species are located in the 8-MR side pockets of MOR, and it consists of two Cu ions and one Al linked by O. This Cu-Al-oxo cluster shows an activity per Cu in methane oxidation significantly higher than of any previously reported active Cu-oxo species. In order to determine unambiguously the structure of the active Cu-Al-oxo cluster, we combine experimental XANES of Cu K- and L-edges, Cu K-edge HERFD-XANES, and Cu K-edge EXAFS with TDDFT and AIMD-assisted simulations. Our results provide evidence of a [CuAlO] cluster exchanged on MOR Al pairs that is able to oxidize up to two methane molecules per cluster at ambient pressure.
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http://dx.doi.org/10.1021/jacsau.1c00196DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8479761PMC
September 2021

RIP2 knockdown inhibits cartilage degradation and oxidative stress in IL-1β-treated chondrocytes via regulating TRAF3 and inhibiting p38 MAPK pathway.

Clin Immunol 2021 11 26;232:108868. Epub 2021 Sep 26.

Department of Orthopaedics, Xijing Hospital, Air Force Military Medical University, Xi'an 710032, Shaanxi, China. Electronic address:

Receptor-interacting protein 2 (RIP2) is a key mediator implicated in multiple cellular processes, and its dysregulation has been recently reported in colitis, asthma and other inflammatory diseases. However, the effects of RIP2 on osteoarthritis (OA) and the underlying mechanisms remain unclear. In this study, we found that RIP2 expression was upregulated in human articular cartilage tissues with OA and interleukin-1β (IL-1β)-treated chondrocytes. Knockdown of RIP2 inhibited IL-1β-induced extracellular matrix (ECM) and oxidative stress. Moreover, knockdown of TRAF3 reversed the effects of RIP2 silencing on cartilage degradation and oxidative stress in IL-1β-induced chondrocytes. In addition, p38 mitogen-activated protein kinase (MAPK) activator dehydrocorydalmine chloride (Dc) also reversed the effects of RIP2 silencing on IL-1β-induced chondrocytes. Taken together, our data reveal that RIP2 knockdown inhibits cartilage degradation and oxidative stress in IL-1β-treated chondrocytes by regulating TRAF3 expression and p38 MAPK pathway activation.
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http://dx.doi.org/10.1016/j.clim.2021.108868DOI Listing
November 2021

Direct 1,2-Dicarbonylation of Alkenes towards 1,4-Diketones via Photocatalysis.

Angew Chem Int Ed Engl 2021 Sep 29. Epub 2021 Sep 29.

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing, 100190, P. R. China.

1,4-Dicarbonyl compounds are intriguing motifs and versatile precursors in numerous pharmaceutical molecules and bioactive natural compounds. Direct incorporation of two carbonyl groups into a double bond at both ends is straightforward, but also challenging. Represented herein is the first example of 1,2-dicarbonylation of alkenes by photocatalysis. Key to success is that N(n-Bu) not only associates with the alkyl anion to avoid protonation, but also activates the α-keto acid to undergo electrophilic addition. The α-keto acid is employed both for acyl generation and electrophilic addition. By tuning the reductive and electrophilic ability of the acyl precursor, unsymmetric 1,4-dicarbonylation is achieved for the first time. This metal-free, redox-neutral and regioselective 1,2-dicarbonylation of alkenes is executed by a photocatalyst for versatile substrates under extremely mild conditions and shows great potential in biomolecular and drug molecular derivatization.
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http://dx.doi.org/10.1002/anie.202112370DOI Listing
September 2021

Effect of Nonwoven Carbon Tissue-Reinforced Epoxy Resin Adhesive Layer on the Single Lap Bonding Strength of Aluminum Alloy Joints.

ACS Omega 2021 Sep 6;6(37):23802-23813. Epub 2021 Sep 6.

State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, China.

The present paper provides a solution to enhance the reliability of bonding. The effect of the nonwoven carbon tissue (NWCT) composite adhesive layer on the bonding strength and reliability of aluminum alloy of single lap joints (SLJ) was investigated by embedding NWCT into the epoxy adhesive layer. The bonding strength, Weibull distribution, metallography of cross section, and fracture surface morphology of NWCT specimens were investigated. The results showed that the average bonding strength and Weibull characteristic strength (WCS) of NWCT-reinforced specimen were 16.78 and 17.17 MPa, which increased by 70.2 and 66.7%, respectively, compared with the neat specimen, and the Weibull modulus increased from 11.46 to 22.83, which indicated that NWCT specimens had higher bonding reliability. The mechanism of microcrack formation was obtained by analyzing the cross section of specimen loaded 95% WCS without macroscopic damage. The metallographic section showed that the microcrack of the neat specimen originated from the adhesive-aluminum interface, while the microcracks of the NWCT specimen originated from the interface between short carbon fibers (SCF) and adhesive. Typical failure modes were gained from visual observation and SEM. The failure mode of the neat specimen included more Al-adhesive interface failure, while the NWCT specimen included more internal failure of adhesive-SCFs with the fracture, pullout, peeling, and slippage of SCFs improving the toughness and bonding strength of the adhesive layer. The bridging effect of SCFs in the adhesive layer reinforced by NWCT can even the load and release the stress to improve the bonding reliability.
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http://dx.doi.org/10.1021/acsomega.1c02635DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8459363PMC
September 2021

Gardenoside Hinders Caspase-1-Mediated Hepatocyte Pyroptosis Through the CTCF/DPP4 Signaling Pathway.

Front Physiol 2021 8;12:669202. Epub 2021 Sep 8.

Department of Endocrinology, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.

Non-alcoholic fatty liver disease (NAFLD)is accompanied by typical inflammatory damage and cell death. As a pro-inflammatory form of cell death, pyroptosis participates in important pathological processes involved in NAFLD. Regulatory roles of both CCCTC-binding factor (CTCF) and dipeptidyl peptidase-4 (DPP4) have been reported in NAFLD, but it is still unclear whether the mechanism of action of gardenoside, a potential therapeutic for NAFLD, can be driven these proteins. In this study, the direct interaction between CTCF and DPP4 was first confirmed by a dual-luciferase reporter assay system. Then, a cell model of NAFLD was established by induction with palmitic acid (PA) and lipopolysaccharide (LPS). A mouse NAFLD model was established, and the effect of gardenoside on both the cell and mouse models of NAFLD was also investigated. Increased lipid accumulation, NLRP3 inflammasome activation, and hepatocyte pyroptosis were recorded in NAFLD and . Gardenoside treatment effectively reduced the lipid accumulation, increased cell viability, reduced reactive oxygen species (ROS) generation, and attenuated pyroptosis and apoptosis in NAFLD in the and models. Alterations in these biological processes were evidenced by the decreased expression levels of several pro-pyroptotic markers including the NLR family, pyrin domain-containing 3 (NLRP3), apoptosis-related speckle-like protein (ASC), caspase-1 p20, Gasdermin D N-terminal domain (GSDMD-N), and IL-1β, along with simultaneously decreased CTCF and DPP4 levels. Importantly, CTCF silencing or DPP4 silencing exhibited effects similar to gardenoside treatment, while CTCF overexpression counteracted this trend, which indicated that CTCF might be a target responsible for gardenoside-induced alleviation of NAFLD, such therapeutic effects might be achieved through controlling the expression of the direct target of CTCF (DPP4) and several downstream molecules. In general, the current study provides a promising strategy for NAFLD treatment.
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http://dx.doi.org/10.3389/fphys.2021.669202DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8455910PMC
September 2021

Suppression of 4.1R enhances the potency of NKG2D-CAR T cells against pancreatic carcinoma via activating ERK signaling pathway.

Oncogenesis 2021 Sep 21;10(9):62. Epub 2021 Sep 21.

Shanghai Key Laboratory of Regulatory Biology, School of Life Sciences, East China Normal University, 200241, Shanghai, China.

Pancreatic carcinoma (PC) is one of the most common malignancies. Chimeric antigen receptor (CAR)-modified T cells has achieved remarkable efficacy in the treatment of hematological malignancies. However, lack of tumor-specific targets and the existence of inhibitory factors limit the function of CAR T cells when treating solid tumors. 4.1R has been reported to suppress the anti-tumor activity of T cell responses. In this study, we investigated the anti-tumor activity of 4.1R deletion in natural killer group 2D (NKG2D)-CAR T cells against PC. The CAR T cells were obtained by transfecting T cells with lentiviral vector carrying NKG2D-CAR, NC-NKG2D-CAR, or KD2-NKG2D-CAR. In vitro, NKG2D-CAR T cells showed higher cytotoxicity than Mock T cells. However, compared to NKG2D-CAR T cells, furtherly higher cytotoxicity against PC cells in a dose-dependent manner was found in KD2-NKG2D-CAR T cells. In addition, the proliferation rate and cytotoxic activity of KD2-NKG2D-CAR T cells were significantly higher than those of NKG2D-CAR T cells. Besides, the inhibitory receptors PD-1 and TIM-3 were expressed in lower level on KD2-NKG2D-CAR T cells. In vivo, KD2-NKG2D-CAR T cells suppressed tumor growth more effectively in a xenograft model compared to NKG2D-CAR T cells. Mechanistically, 4.1R regulated CAR T cell function via activating ERK signaling pathway. Therefore, the study provides a new idea to enhance the anti-tumor efficiency of CAR T therapy.
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http://dx.doi.org/10.1038/s41389-021-00353-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8455638PMC
September 2021

Spatiotemporally dynamic therapy with shape-adaptive drug-gel for the improvement of tissue regeneration with ordered structure.

Bioact Mater 2022 Feb 23;8:165-176. Epub 2021 Jun 23.

Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China.

A spatiotemporally dynamic therapy (SDT) is proposed as a powerful therapeutic modality that provides spatially dynamic responses of drug-carriers for adapting to the wound microenvironment. Herein, dynamic chitosan-poly (ethylene glycol) (CP) Schiff-base linkages are employed to perform SDT by directly converting a liquid drug (KFX) into a gel formation. The obtained KFX-CP drug-gel with shape-adaptive property is used to treat a representative oral mucositis (OM) model in a spatiotemporally dynamic manner. The KFX-CP drug-gel creates an instructive microenvironment to regulate signaling biomolecules and endogenous cells behavior, thereby promoting OM healing by the rule of dynamically adjusting shape to fit the irregular OM regions first, and then provides space for tissue regeneration, over KFX potion control and the general hydrogel group of CP hydrogel and KFX-F127. Most interestingly, the regenerated tissue has ordered structure like healthy tissue. Therefore, the SDT provides a new approach for the design of next generation of wound dressing and tissue engineering materials.
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http://dx.doi.org/10.1016/j.bioactmat.2021.06.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8424390PMC
February 2022

Universal Strategy to Prepare a Flexible Photothermal Absorber Based on Hierarchical Fe-MOF-74 toward Highly Efficient Solar Interfacial Seawater Desalination.

ACS Appl Mater Interfaces 2021 Sep 15;13(38):45944-45956. Epub 2021 Sep 15.

Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Material, School of Materials Science and Engineering, Shaanxi University of Science & Technology, Xi'an 710021, Shaanxi, China.

Solar-driven interfacial steam generation (SDISG), as an emerging green and renewable approach to overcome water shortage, is very suitable for remote locations, developing countries, and disaster zones because it does not require an additional energy supply. However, the traditional metal-based and carbon-based absorbers always suffered from fragility (or rigidity) and the complex preparation process, which dramatically inhibited their transportation and installation in areas with poor infrastructure. Therefore, there is an urgent need to develop a universal method to fabricate flexible solar evaporators. Herein, a novel solar evaporator that integrates a flexible matrix (Cu mesh or textile) and a hierarchical Fe-MOF-74 photothermal absorber component is perfectly prepared for the rapid and efficient SDISG. Notably, the results show that Fe-MOF-74-based flexible textile matrix composites exhibit outstanding light absorption (83.81%), low thermal conductivity (0.1730 W/m K), super hydrophilic properties (within 50 ms, the contact angle is close to 0°), excellent salt resistance, high evaporation rate (1.35 kg/m h), and photothermal conversion efficiency (η is 81.5% under one sun, stable for 30 days). Owing to the flexibility, recyclability, and above-mentioned excellent performance, the prepared hierarchical Fe-MOF-74-based flexible composite systems are more practical for transportation, large-scale production, and stable and efficient applications. As a result, this work offers new insight into the future development of the combination of a MOF-based photothermal absorber and flexible substrates, as well as for the application of interfacial solar seawater desalination, and provides a new reference for other applications.
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http://dx.doi.org/10.1021/acsami.1c11176DOI Listing
September 2021

Lipidomic profiling reveals lipid regulation by a novel LSD1 inhibitor treatment.

Oncol Rep 2021 11 9;46(5). Epub 2021 Sep 9.

State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, and Collaborative Innovation Center for Biotherapy, Sichuan University, Chengdu, Sichuan 610041, P.R. China.

Lipid metabolic alterations are associated with cancer progression. Lysine‑specific demethylase 1 (LSD1) plays a crucial role in cancer and has become a promising target for cancer therapy. However, the effect of LSD1 on lipid metabolism remains unclear. In the present study, we used a LC‑MS/MS‑based lipidomics approach to investigate the impact of LSD1 on cancer cell lipid metabolism using ZY0511, a specific LSD1 inhibitor developed by our group as a specific probe. ZY0511 profoundly modified the human colorectal and cervical cancer cell lipid metabolism. A total of 256 differential metabolites were identified in HeLa cells, and 218 differential metabolites were identified in HCT116 cells, respectively. Among these lipid metabolites, phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine and sphingomyelin (SM) were downregulated by ZY0511. In contrast, ceramide (Cer) and a small portion of glycerophospholipids such as phosphatidylinositol and phosphatidylethanolamine were upregulated by ZY0511. These results revealed a disturbance in sphingolipids (SPs) and glycerophospholipids, which may be correlated with the progression of cancer. Furthermore, a marked increase in Cer and prominent decrease in SM were consistent with the upregulated expression of key enzymes in the Cer synthesis process including synthesis, hydrolysis of SM and the salvage pathway after ZY0511 exposure. In conclusion, our research reveals a link between LSD1 and lipid metabolism in cancer cells, offering more comprehensive evidence for the application of LSD1 inhibitors for cancer therapy. The underlying mechanisms of how the LSD1 inhibitor regulates lipid metabolism warrant further investigation.
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http://dx.doi.org/10.3892/or.2021.8184DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8444191PMC
November 2021

Antigenic Diversity of Human Norovirus Capsid Proteins Based on the Cross-Reactivities of Their Antisera.

Pathogens 2021 Aug 5;10(8). Epub 2021 Aug 5.

Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.

Human norovirus (HuNoV), which is the major causative agent of acute gastroenteritis, has broad antigenic diversity; thus, the development of a broad-spectrum vaccine is challenging. To establish the relationship between viral genetic diversity and antigenic diversity, capsid P proteins and antisera of seven GI and 16 GII HuNoV genotypes were analyzed. Enzyme-linked immunosorbent assays showed that HuNoV antisera strongly reacted with the homologous capsid P proteins (with titers > 5 × 10). However, 17 (73.9%) antisera had weak or no cross-reactivity with heterologous genotypes. Interestingly, the GII.5 antiserum cross-reacted with seven (30.4%) capsid P proteins (including pandemic genotypes GII.4 and GII.17), indicating its potential use for HuNoV vaccine development. Moreover, GI.2 and GI.6 antigens reacted widely with heterologous antisera (n ≥ 5). Sequence alignment and phylogenetic analyses of the P proteins revealed conserved regions, which may be responsible for the immune crossover reactivity observed. These findings may be helpful in identifying broad-spectrum epitopes with clinical value for the development of a future vaccine.
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http://dx.doi.org/10.3390/pathogens10080986DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8398591PMC
August 2021

OIP5-AS1 contributes to the development in endometrial carcinoma cells by targeting miR-152-3p to up-regulate SLC7A5.

Cancer Cell Int 2021 Aug 21;21(1):440. Epub 2021 Aug 21.

Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong Univercity of Science and Technology, No. 2177 Liberation Avenue, Wuhan, 430022, China.

Background: Endometrial carcinoma (EC) is one common gynecological tumor, threatening physical and psychological health of females. Huge amount of essays indicated that long non-coding RNAs (lncRNAs) were widely reported to serve as a crucial regulator in the biological movements among multiple carcinomas, including EC.

Methods: RT-qPCR was implemented to detect the expression of target genes. Loss/gain-of-function experiments certified the impacts of OIP5-AS1 and miR-152-3p on EC cell progression.

Results: Data of this research suggested that powerful expression of OIP5-AS1 was discovered in EC cell lines. Loss/gain-of-function assays inferred that OIP5-AS1 promoted proliferative, migratory and invasive abilities, and Epithelial-Mesenchymal Transition (EMT). In addition, we identified miR-152-3p expression was negatively modulated by OIP5-AS1. OIP5-AS1 accelerated the development of EC cells via downregulating miR-152-3p expression. SLC7A5 was selected out as a downstream target of miR-152-3p. The competing relationship between OIP5-AS1 and SLC7A5 was corroborated by luciferase reporter assay. Eventually, the results of rescue assays indicated that SLC7A5 overexpression could restore the impacts of OIP5-AS1 ablation on the progression of EC cells.

Conclusion: Our research confirmed that OIP5-AS1 propeled the development of EC cells through targeting miR-152-3p/SLC7A5. OIP5-AS1 could be utilized as a target for EC treatment.
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http://dx.doi.org/10.1186/s12935-021-02061-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8379738PMC
August 2021

Antibiotic Resistance Characterization of Bacteria Isolated from Traditional Chinese Paocai.

Curr Microbiol 2021 Nov 14;78(11):3853-3862. Epub 2021 Aug 14.

Meishan Product Quality Supervision and Inspection Institute, Meishan, 620000, China.

In this work, the antibiotic resistance of 218 isolates to 9 different antibiotics was analyzed with minimum inhibitory concentration method. All Lactobacillus pentosus strains were found to be resistant to streptomycin sulfate and ciprofloxacin hydrochloride. Lactococcus lactis strains were resistant to streptomycin sulfate. Specifically, 90% Klebsiella oxytoca and all Citrobacter freundii strains were resistant to ampicillin sodium. 30% K. oxytoca strains were resistant to ciprofloxacin hydrochloride. All Bacillus albus strains were resistant to erythromycin and 80% strains were resistant to ampicillin sodium. Results from PCR analysis revealed that 90 isolates carried the aadE gene. The tetM gene was detected in four L. pentosus isolates. And the streptomycin resistant gene aadA was detected in one L. pentosus isolate. Metagenome analysis revealed that 74.7% genes associated with antibiotic resistance were antibiotic resistance genes. The tetM and aadA genes, detected in PCR analysis, were also retrieved from the paocai metagenome. In brief, this study generated the antibiotic resistance profile of some paocai-originated bacteria strains. L. pentosus found in the final edible paocai were inherently resistant to antibiotics, such as streptomycin and ciprofloxacin. Results in this work reminds us to carefully choose the LAB strains for traditional Chinese paocai production to avoid potential spreading of antibiotic resistant genes.
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http://dx.doi.org/10.1007/s00284-021-02629-zDOI Listing
November 2021

Genetic Diversity and Population Structure of Isolated From Clinical and Food Sources.

Front Microbiol 2021 27;12:708795. Epub 2021 Jul 27.

Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China.

is a common foodborne pathogen that causes gastroenteritis worldwide. Determining its prevalence and genetic diversity will minimize the risk of infection and the associated economic burden. Multilocus sequence typing (MLST) is an important tool for molecular epidemiology and population genetic studies of bacteria. Here, we analyzed the genetic and evolutionary relationships of 162 strains isolated in the Guangdong Province, China, using MLST. In the study, 120 strains were isolated from food samples, and 42 strains were isolated from clinical samples. All strains were categorized into 100 sequence types (STs), of which 58 were novel (48 from the food isolates and 10 from the clinical isolates). ST415 was the most prevalent ST among the food isolates, while ST3 was the most prevalent ST among the clinical isolates. Further, 12 clonal complexes, 14 doublets, and 73 singletons were identified in all ST clusters, indicating high genetic diversity of the analyzed strains. At the concatenated sequence level, non-synonymous sites in both, food and clinical isolates, were associated with purifying selection. Of note, the / ration was greater than 1 for some housekeeping genes in all isolates. This is the first time that some loci under positive selection were identified. These observations confirm frequent recombination events in . Recombination was much more important than mutation for genetic heterogeneity of the food isolates, but the probabilities of recombination and mutations were almost equal for the clinical isolates. Based on the phylogenetic analysis, the clinical isolates were concentrated in the maximum-likelihood tree, while the food isolates were heterogeneously distributed. In conclusion, the food and clinical isolates of from the Guangdong Province are similar, but show different evolutionary trends. This may help prevent large-scale spread of highly virulent strains and provides a genetic basis for the discovery of microevolutionary relationships in populations.
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http://dx.doi.org/10.3389/fmicb.2021.708795DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8353399PMC
July 2021

High prevalence of multidrug-resistant Escherichia coli and first detection of IncHI2/IncX4-plasmid carrying mcr-1 E. coli in retail ready-to-eat foods in China.

Int J Food Microbiol 2021 Oct 30;355:109349. Epub 2021 Jul 30.

Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong Province 510070, China. Electronic address:

Antibiotic-resistant bacteria in food pose an important threat to public health. Multidrug-resistant strains in ready-to-eat (RTE) foods can be transferred to humans through diet, which increases their health risk. This study systematically investigated antibiotic resistance and antibiotic resistance genes in E. coli isolated from retail RTE foods and characterized plasmid-mediated colistin-resistant E. coli strains. A total of 1118 RTE food samples were collected from markets in 39 cities in China, and 126 E. coli strains, >95% of which were multidrug-resistant, were isolated. The isolates showed a high prevalence of resistance to tetracycline (95.24%), ampicillin (82.54%), trimethoprim-sulfamethoxazole (77.78%), nalidixic acid (74.60%), cephalothin (72.22%), chloramphenicol (66.67%), and streptomycin (53.97%). Twenty-two extended-spectrum β-lactamase (ESBL)-producing E. coli and four colistin-resistant E. coli were identified. The resistance genes TEM, CTX-M, tetA, sul2, strA/strB, aadA, and qnrS were the most frequently detected. CTX-M-55 and CTX-M-14 were the predominant CTX-M types. All the four colistin-resistant E. coli isolates were positive for mcr-1. The mcr-1 gene can be transferred to E. coli C600 through conjugation and transformation. Whole-genome sequencing revealed that the mcr-1 genes were found in IncX4 and IncHI2 plasmids. To the best of our knowledge, this is the first report of IncHI2/IncX4 plasmid-bearing mcr-1-positive E. coli strains in RTE foods sold in markets, and the first report of the isolation of the international epidemic E. coli clone ST101 and mcr-1-carrying ESBL-producing E. coli from RTE foods. These results provide valuable information for assessing antibiotic-resistant E. coli infections and controlling antibiotic-resistant E. coli.
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http://dx.doi.org/10.1016/j.ijfoodmicro.2021.109349DOI Listing
October 2021

[Postoperative prognostic risk factors and treatment strategies for patients with T3-T4 hypopharyngeal squamous cell carcinoma].

Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2021 May;35(5):400-404;409

Department of Otolaryngology Head and Neck Surgery,Eye Ear Nose and Throat Hospital of Fudan University,Shanghai,200031,China.

To investigate the independent prognostic risk factors and the application of different postoperative adjuvant treatment strategies on patients with T3-T4 hypopharyngeal carcinoma. Based on the inclusion criteria, we conducted a retrospective study that analyzed the clinical data of 229 cases who underwent surgery at the Eye, Ear, Nose and Throat Hospital of Fudan University from 2003 to 2015. Risk factors for postoperative survival were analyzed by univariate and multivariate analysis and patients were stratified according to the independent risk factors. The efficacy of various postoperative adjuvant therapystrategies were compared in different risk groups. Two hundred and twenty-nine patients with T3-T4 primary tumor had 3-year and 5-year overall survival rates of 39.07% and 29.03%, respectively; 3-year and 5-year recurrence-free survival rates were 40.22% and 30.29%, respectively. The results of multivariate analysis demonstrated that tumors in the posterior pharyngeal wall and posterior cricoid region, N2c-N3, lymphovascular invasion, and extranodal extension were independent risk factors. The utility of postoperative adjuvant therapy significantly improved postoperative survival in the high-risk group (<0.05) and reduced postoperative recurrence significantly (<0.01). Patients received adjuvant chemoradiation had better survival than those received adjuvant radiation alone (<0.05). Postoperative adjuvant therapy had no significant effect on postoperative survival of patients in the low-risk group. Independent risk factors for patients with T3-T4 hypopharyngeal carcinoma include tumors in the posterior pharyngeal wall and posterior cricoid region, N2c-N3, lymphovascular invasion, as well as extranodal extension. Postoperative adjuvant therapy, especially adjuvant chemoradiation,is recommended for patient with risk factors mentioned above. For patients without those risk factors, postoperative follow-up and re-examination are recommended.
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http://dx.doi.org/10.13201/j.issn.2096-7993.2021.05.004DOI Listing
May 2021
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