Publications by authors named "Xiaoyan Liu"

997 Publications

A new workflow on bone marrow aspiration and biopsy during the COVID-19 pandemic.

Arch Med Sci 2021 25;17(5):1429-1432. Epub 2021 Jul 25.

Department of Haematology, Zhongnan Hospital of Wuhan University, Wuhan, China.

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http://dx.doi.org/10.5114/aoms/140395DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8425222PMC
July 2021

Near 100% ethene selectivity achieved by tailoring dual active sites to isolate dehydrogenation and oxidation.

Nat Commun 2021 Sep 14;12(1):5447. Epub 2021 Sep 14.

CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, People's Republic of China.

Prohibiting deep oxidation remains a challenging task in oxidative dehydrogenation of light alkane since the targeted alkene is more reactive than parent substrate. Here we tailor dual active sites to isolate dehydrogenation and oxidation instead of homogeneously active sites responsible for these two steps leading to consecutive oxidation of alkene. The introduction of HY zeolite with acid sites, three-dimensional pore structure and supercages gives rise to Ni Lewis acid sites (LAS) and NiO nanoclusters confined in framework wherein catalytic dehydrogenation of ethane occurs on Ni LAS resulting in the formation of ethene and hydrogen while NiO nanoclusters with decreased oxygen reactivity are responsible for selective oxidation of hydrogen rather than over-oxidizing ethene. Such tailored strategy achieves near 100% ethene selectivity and constitutes a promising basis for highly selective oxidation catalysis beyond oxidative dehydrogenation of light alkane.
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http://dx.doi.org/10.1038/s41467-021-25782-2DOI Listing
September 2021

Antioxidative and Angiogenic Hyaluronic Acid-Based Hydrogel for the Treatment of Peripheral Artery Disease.

ACS Appl Mater Interfaces 2021 Sep 14. Epub 2021 Sep 14.

Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States.

Peripheral arterial disease (PAD) is a progressive atherosclerotic disorder characterized by blockages of the arteries supplying the lower extremities. Ischemia initiates oxidative damage and mitochondrial dysfunction in the legs of PAD patients, causing injury to the tissues of the leg, significant decline in walking performance, leg pain while walking, and in the most severe cases, nonhealing ulcers and gangrene. Current clinical trials based on cells/stem cells, the trophic factor, or gene therapy systems have shown some promising results for the treatment of PAD. Biomaterial matrices have been explored in animal models of PAD to enhance these therapies. However, current biomaterial approaches have not fully met the essential requirements for minimally invasive intramuscular delivery to the leg. Ideally, a biomaterial should present properties to ameliorate oxidative stress/damage and failure of angiogenesis. Recently, we have created a thermosensitive hyaluronic acid (HA) hydrogel with antioxidant capacity and skeletal muscle-matching stiffness. Here, we further optimized HA hydrogels with the cell adhesion peptide RGD to facilitate the development of vascular-like structures . The optimized HA hydrogel reduced intracellular reactive oxygen species levels and preserved vascular-like structures against HO-induced damage . HA hydrogels also provided prolonged release of the vascular endothelial growth factor (VEGF). After injection into rat ischemic hindlimb muscles, this VEGF-releasing hydrogel reduced lipid oxidation, regulated oxidative-related genes, enhanced local blood flow in the muscle, and improved running capacity of the treated rats. Our HA hydrogel system holds great potential for the treatment of the ischemic legs of patients with PAD.
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http://dx.doi.org/10.1021/acsami.1c11349DOI Listing
September 2021

Long noncoding RNA KCNMB2-AS1 promotes the development of esophageal cancer by modulating the miR-3194-3p/PYGL axis.

Bioengineered 2021 Dec;12(1):6687-6702

Department of Urology, The Affiliated Lianyungang Hospital of Xuzhou Medical University, The First People's Hospital of Lianyungang, Lianyungang, Jiangsu, China.

Esophageal cancer (ESCA), as a common cancer worldwide, is a main cause of cancer-related mortality. Comprehensive studies on molecular mechanism of ESCA have been carried out. Though numerous long noncoding RNAs (lncRNAs) was reported to participate in the occurrence and development of ESCA, the potential role of lncRNA potassium calcium-activated channel subfamily M regulatory beta subunit 2 (KCNMB2) antisense RNA 1 (KCNMB2-AS1) in ESCA remains to be discovered. This study intends to investigate the detailed function and molecular mechanism of KCNMB2-AS1 in ESCA. Gene expression was evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Cell proliferation was examined by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Cell invasion and migration were measured by wound healing assay and Transwell assay. Luciferase reporter assay was adopted to validate the interaction between KCNMB2-AS1 and miR-3194-3p. Western blotting was performed to assess protein levels. We discovered that KCNMB2-AS1 was significantly upregulated in ESCA. KCNMB2-AS1 downregulation suppressed the growth, invasion, migration and stemness of ESCA cells. KCNMB2-AS1 bound with miR-3194-3p, and glycogen phosphorylase L (PYGL) was a direct target of miR-3194-3p. KCNMB2-AS1 upregulated PYGL expression by directly binding with miR-3194-3p. Additionally, PYGL overexpression abolished the inhibitory influence of KCNMB2-AS1 depletion on ESCA cell behaviors. Collectively, lncRNA KCNMB2-AS1 promotes ESCA development through targeting the miR-3194-3p/ PYGL axis, which might provide theoretical basis to explore novel biomarkers for ESCA treatment.
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http://dx.doi.org/10.1080/21655979.2021.1973775DOI Listing
December 2021

A feasible self-assembled near-infrared fluorescence sensor for acid phosphatase detection and cell imaging.

Analyst 2021 Sep 13;146(18):5558-5566. Epub 2021 Sep 13.

College of Chemical Engineering, Northwest Minzu University, Lanzhou, Gansu 730030, China.

The single signal amplification strategy is significant for detecting various disease biomarkers but is restricted by its limited accuracy. The multi-signal and multi-mode methods have overcome this deficiency. Acid phosphatase (ACP) is an important intracellular enzyme but one-step cell imaging material-based probes are scarce for ACP. Herein, we designed a one-step self-assembled polymer probe using neutral red (NR), modified-(pyridoxal-5'-phosphate (PLP)) and Eu. The polymer exhibited non-emission and excellent stability. Upon the catalytic hydrolysis reaction of ACP, the polymer exhibited two strong fluorescence signals at 373 nm and 613 nm and an appreciable decline of absorbance at 395 nm. The probe has excellent selectivity and higher sensitivity with a limit of detection as low as 0.02 mU mL. It possesses favorable biocompatibility and has been successfully used to detect and image intracellular ACP in several living cells.
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http://dx.doi.org/10.1039/d1an01218eDOI Listing
September 2021

Epilepsy centers in China: Current status and ways forward.

Epilepsia 2021 Sep 12. Epub 2021 Sep 12.

Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.

Objective: China has the largest population of patients with epilepsy worldwide, which imposes a heavy burden on the public and health care systems. Several epidemiological surveys on epilepsy have been performed in China. Although these surveys grossly describe the prevalence and gap in treatment of epilepsy, the status of epilepsy centers is unclear. The number of epilepsy centers has increased substantially in recent decades. Therefore, a nationwide investigation of the scale and distribution, personnel, equipment, and epilepsy care capacity of each epilepsy center is of great value.

Methods: In 2017-2018, a multicenter cross-sectional survey was performed by the Commission on Standardized Development of Epilepsy Centers, China Association Against Epilepsy in 31 provinces, autonomous regions, and municipalities. The survey consisted of 74 questions divided into four sections: (1) overview, (2) personnel, (3) essential equipment and facilities, and (4) epilepsy care service capacity. The questions ranged from January 1, 2016 to December 31, 2016. The data were analyzed using descriptive statistics.

Results: There were 358 epilepsy centers for the 1.38 billion national population in 2016. Three quarters were in the eastern and western regions, and >90% were in tertiary hospitals. There were 9688 doctors engaged in epilepsy care, and 4.8% of doctors and electrophysiological physicians/technicians passed the national test for electroencephalography technical accreditation. A total of 9667 patients underwent resective surgeries in 2016. There were 888 vagus nerve stimulation procedures and 275 deep brain stimulation procedures.

Significance: This study is the first unique survey of epilepsy centers in China. Despite their rapid development, epilepsy centers cannot meet patients' needs at this stage. The results provide data-based evidence for the formulation of policies related to epilepsy service planning.
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http://dx.doi.org/10.1111/epi.17058DOI Listing
September 2021

Elucidation of Distinct Modular Assemblies of Smoothened Receptor by Bitopic Ligand Measurement.

J Med Chem 2021 Sep 7. Epub 2021 Sep 7.

iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Shanghai 201210, China.

Class F G protein-coupled receptors are characterized by a large extracellular domain (ECD) in addition to the common transmembrane domain (TMD) with seven α-helixes. For smoothened receptor (SMO), structural studies revealed dissected ECD and TMD, and their integrated assemblies. However, distinct assemblies were reported under different circumstances. Using an unbiased approach based on four series of cross-conjugated bitopic ligands, we explore the relationship between the active status and receptor assembly. Different activity dependency on the linker length for these bitopic ligands corroborates the various occurrences of SMO assembly. These results reveal a rigid "near" assembly for active SMO, which is in contrast to previous results. Conversely, inactive SMO adopts a free ECD, which would be remotely captured at "far" assembly by cholesterol. Altogether, we propose a mechanism of cholesterol flow-caused SMO activation involving an erection of ECD from far to near assembly.
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http://dx.doi.org/10.1021/acs.jmedchem.1c01220DOI Listing
September 2021

Comparison of monoclonal antibodies targeting CD38, SLAMF7 and PD-1/PD-L1 in combination with Bortezomib/Immunomodulators plus dexamethasone/prednisone for the treatment of multiple myeloma: an indirect-comparison Meta-analysis of randomised controlled trials.

BMC Cancer 2021 Sep 6;21(1):994. Epub 2021 Sep 6.

Department of Hematology, West China Hospital, Sichuan University, Chengdu, No.37 GuoXue Xiang, Chengdu, 610041, Sichuan Province, China.

Background: Many clinical trials have assessed the effect and safety of monoclonal antibodies (MAbs) in combination with proteasome inhibitors or immunomodulators plus dexamethasone/prednisone for the treatment of multiple myeloma (MM). The treatment outcomes of comparing different MAbs in combination with the above-mentioned agents remained unclear. We performed the meta-analysis to indirectly compare the effect and safety of MAbs targeting CD38, SLAMF7, and PD-1/PD-L1 in combination with bortezomib/immunomodulators plus dexamethasone/prednisone for patients with MM.

Methods: We searched thoroughly in the databases for randomised controlled trials (RCTs) in which at least one of the three MAbs were included. We included eleven eligible RCTs with 5367 patients in the meta-analysis. Statistical analysis was carried out using StataMP14 and Indirect Treatment Comparisons software.

Results: We calculated hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) and relative risk (RR) for overall response rate, complete response (CR) or better, very good partial response (VGPR) or better, VGPR, partial response, stable disease, and grade 3 or higher adverse events among the three groups. The HRs for PFS of the CD38 group vs SLAMF7 group, CD38 group vs PD-1/PD-L1 group, and SLAMF7 group vs PD-1/PD-L1 group were 0.662 (95%CI 0.543-0.806), 0.317 (95%CI 0.221-0.454), and 0.479 (95%CI 0.328-0.699), respectively. The HR for OS of the CD38 group vs SLAMF7 group was 0.812 (95%CI 0.584-1.127). The RR for CR or better in the CD38 group vs SLAMF7 group was 2.253 (95%CI 1.284-3.955). The RR for neutropenia of the CD38 group vs SLAMF7 group was 1.818 (95%CI 1.41-2.344).

Conclusions: Treatment with the CD38 group had longer PFS and better treatment response than that with the SLAMF7 or PD-1/PD-L1 group. In addition, the SLAMF7 group prolonged PFS compared with the PD-1/PD-L1 group and was associated with a lower incidence of grade 3 or higher neutropenia than the CD38 and PD-1/PD-L1 group. In conclusion, MAbs targeting CD38 are the best, followed by those targeting SLAMF7; MAbs targeting PD-1/PD-L1 are the worst when in combination with bortezomib/immunomodulators plus dexamethasone/prednisone for the treatment of MM.
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http://dx.doi.org/10.1186/s12885-021-08588-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8419924PMC
September 2021

Engineering a "three-in-one" hirudin prodrug to reduce bleeding risk: A proof-of-concept study.

J Control Release 2021 Sep 1;338:462-471. Epub 2021 Sep 1.

Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, China; Laboratory of innovative formulations and pharmaceutical excipients, Ningbo Institute of Marine Medicine, Peking University, Beijing, China. Electronic address:

An ideal anticoagulant should have at least three properties including targeted delivery to the thrombosis site, local activation or releasing to centralize the anti-thrombosis effects and thus reduce the bleeding risks, and long persistence in circulation to avoid repeated administration. In the present study, we sought to test a "three-in-one" strategy to design new protein anticoagulants. Based on these criteria, we constructed two hirudin prodrugs, R824-HV-ABD and ABD-HV-R824. The R824 peptide can bind phosphatidylserine on the surface of the procoagulant platelets and thus guide the prodrug to the thrombosis sites; albumin-binding domain (ABDs) can bind the prodrug to albumin, and thereby increase its persistence in circulation; the hirudin (HV) core in the prodrug is flanked by factor Xa recognition sites, thus factor Xa at the thrombosis site can cleave the fusion proteins and release the activated hirudin locally. Hirudin prodrugs were able to bind with procoagulant platelets and human serum albumin in vitro with high affinity, targeted concentrated and prevented the formation of occlusive thrombi in rat carotid artery injury model. Their effective time was significantly extended compared to native hirudin, and R824-HV-ABD showed a significantly improved half-life of about 24 h in rats. The bleeding time of prodrug-treated mice was much shorter than that of hirudin-treated mice. The results from the proof-of-concept studies, for the first time, demonstrate that "three-in-one" prodrug strategy may be a good solution for protein or peptide anticoagulants to reduce their bleeding risks.
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http://dx.doi.org/10.1016/j.jconrel.2021.08.058DOI Listing
September 2021

Dynamic Behavior of Single-Atom Catalysts in Electrocatalysis: Identification of Cu-N as an Active Site for the Oxygen Reduction Reaction.

J Am Chem Soc 2021 Sep 31;143(36):14530-14539. Epub 2021 Aug 31.

Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.

Atomically dispersed M-N-C (M refers to transition metals) materials represent the most promising catalyst alternatives to the precious metal Pt for the electrochemical reduction of oxygen (ORR), yet the genuine active sites in M-N-C remain elusive. Here, we develop a two-step approach to fabricate Cu-N-C single-atom catalysts with a uniform and well-defined Cu-N structure that exhibits comparable activity and superior durability in comparison to Pt/C. By combining X-ray absorption spectroscopy with theoretical calculations, we unambiguously identify the dynamic evolution of Cu-N to Cu-N and further to HO-Cu-N under ORR working conditions, which concurrently occurs with reduction of Cu to Cu and is driven by the applied potential. The increase in the Cu/Cu ratio with the reduced potential indicates that the low-coordinated Cu-N is the real active site, which is further supported by DFT calculations showing the lower free energy in each elemental step of the ORR on Cu-N than on Cu-N. These findings provide a new understanding of the dynamic electrochemistry on M-N-C catalysts and may guide the design of more efficient low-cost catalysts.
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http://dx.doi.org/10.1021/jacs.1c03788DOI Listing
September 2021

A qualitative and quantitative analysis of the human gingival crevicular fluid proteome and metaproteome.

Proteomics 2021 Aug 31:e2000321. Epub 2021 Aug 31.

Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.

Gingival crevicular fluid (GCF) is an integral part of oral fluid that plays a special role in maintaining the structure of junctional epithelium and defending against bacterial infection. In this study, we comprehensively analysed the composition of the human GCF proteome and metaproteome simultaneously to obtain multidimensional information about GCF. A total of 3680 human proteins (2540 with at least two unique peptides) were identified in the normal GCF sample, and their functions were mainly associated with immune function and inflammation. Among these proteins, 1874 proteins could be quantified by the iBAQ algorithm, and their abundances spanned a dynamic range of six orders of magnitude. For the GCF metaproteome, a total of 3082 proteins and 69 genera were found. In addition, 16 genera were not identified by GCF metagenomic analysis. Compared to the saliva metaproteome, 32 genera were found to be in common. The protein quantitative analysis showed that the abundance of GCF metaproteome contributed to approximately 4.17% of the total GCF proteome. The top three most abundant genera were Fusobacterium, Corynebacterium, and Leptotrichia. The above data will be useful for future research on GCF-related diseases.
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http://dx.doi.org/10.1002/pmic.202000321DOI Listing
August 2021

Pyroptosis, metabolism, and tumor immune microenvironment.

Clin Transl Med 2021 Aug;11(8):e492

Department of Clinical Laboratory, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.

In response to a wide range of stimulations, host cells activate pyroptosis, a kind of inflammatory cell death which is provoked by the cytosolic sensing of danger signals and pathogen infection. In manipulating the cleavage of gasdermins (GSDMs), researchers have found that GSDM proteins serve as the real executors and the deterministic players in fate decisions of pyroptotic cells. Whether inflammatory characteristics induced by pyroptosis could cause damage the host or improve immune activity is largely dependent on the context, timing, and response degree. Here, we systematically review current points involved in regulatory mechanisms and the multidimensional roles of pyroptosis in several metabolic diseases and the tumor microenvironment. Targeting pyroptosis may reveal potential therapeutic avenues.
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http://dx.doi.org/10.1002/ctm2.492DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8329701PMC
August 2021

The relationship between peer victimization and social anxiety among adolescents: a moderated mediation model with cognitive flexibility and affect intensity.

Psychol Health Med 2021 Aug 24:1-13. Epub 2021 Aug 24.

Beijing Key Laboratory of Applied Experimental Psychology, National Demonstration Center for Experimental Psychology Education (Beijing Normal University), Faculty of Psychology, Beijing Normal University, Beijing, P. R. China.

Building a friendship with peers is an important developmental task. However, peer victimization and social anxiety are among the most disturbing problems and have impaired adolescents' adaptive development. A total of 942 adolescents completed the survey. The results showed that peer victimization was related to social anxiety and that this effect was mediated by cognitive flexibility and moderated by affect intensity. Specifically, the damage of peer victimization and social anxiety was aggrevated for those with high levels of affect intensity. The current study provides evidence for the association between peer victimization and social anxiety. It contributes to the literature by clarifying the equivocal findings and uncovering the underlying mechanisms of the relationship between peer victimization and social anxiety. In the future, researchers and teachers should pay attention to adolescents' peer social status as early as possible, especially for adolescents with higher levels of affect intensity.
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http://dx.doi.org/10.1080/13548506.2021.1971729DOI Listing
August 2021

Sequential detection of HS and HOBr with a novel lysosome-targetable fluorescent probe and its application in biological imaging.

J Hazard Mater 2021 Aug 12;422:126898. Epub 2021 Aug 12.

State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China. Electronic address:

Understanding the complex relationship between active small molecules is of great significance in various physiological processes. Herein, we present the design and synthesis of a sequential responsive Lysosome-Naphthalene imide-Azido (lyso-NP-N) reporter for probing the HS and HOBr within organelle (lysosome) in living cells. Probe lyso-NP-N exhibited high selectivity and sensitivity towards HS (LOD = 23.5 nM) and HOBr (LOD = 254 nM). Additionally, lyso-NP-N possessed an excellent lysosome targeting ability and was utilized to visualize the exogenous/endogenous HS and HOBr in RAW 264.7, Hela and HepG2 cells. Facilitated by this sequentially activated mechanism, the probe was successfully applied to confirm that the reported scavenger of HOBr, N-acetyl-L-cysteine (NAC) mainly relied on its metabolite HS to eliminate excess HOBr, thereby playing the role of cell regulation and protection. These results establish the crosstalk between HS and HOBr in lysosome and provide a promising tool to study metabolite interactions.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126898DOI Listing
August 2021

Postoperative seizure and developmental outcomes of children with hemimegalencephaly and drug-resistant epilepsy.

Seizure 2021 Aug 14;92:29-35. Epub 2021 Aug 14.

Pediatric Epilepsy Center, Peking University First Hospital, Beijing, China; Department of Pediatrics, Peking University First Hospital, Beijing, China. Electronic address:

Objective: To evaluate seizure and developmental outcomes in the short and long term in children with hemimegalencephaly (HMEG) after surgery.

Methods: This is a cohort study of 36 children who underwent surgery for HMEG were followed up for at least 1 year postoperatively. The Griffiths Mental Development Scales, Ages and Stages Questionnaire version 3, and Peabody Developmental Motor Scales were used to assess development.

Results: The median postoperative follow-up duration was 2.7 (1.0-5.0) years, and median age at surgery was 1.9 years (5.8 months-5.9 years). At the last follow-up, 83% of children were seizure-free. the predicted probability of being seizure-free three years after surgery was 79%. The proportion of patients who were moderate to severe delay declined from 97% preoperatively to 76% at least 1 year after surgery. Catch-up, stabilization, and regression of developmental quotient (DQ) was observed in 41%, 35%, and 24% of children 3 months after surgery, respectively. The corresponding proportions during long-term follow-up were 40%, 33%, and 27%, respectively. Change of DQ shortly after surgery was negatively correlated with age at seizure onset and age at surgery. The long-term DQ was positively correlated with the preoperative DQ. Long-term change of DQ was positively correlated with change of DQ shortly after surgery.

Conclusions: Most of patients with HMEG could achieve seizure free after surgery. After surgery, the proportion of catch-up, stabilization, and regression in both short- and long-term DQ was approximately 40%, 35%, and 25%, respectively. The change of DQ shortly after surgery may be a predictor for long-term developmental change.
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http://dx.doi.org/10.1016/j.seizure.2021.08.006DOI Listing
August 2021

Serum Metabolites Differentiate Amnestic Mild Cognitive Impairment From Healthy Controls and Predict Early Alzheimer's Disease via Untargeted Lipidomics Analysis.

Front Neurol 2021 2;12:704582. Epub 2021 Aug 2.

Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.

Alzheimer's disease (AD) is the most common type of dementia and presents with metabolic perturbations early in the disease process. In order to explore biomarkers useful in predicting early AD, we compared serum metabolites among patients suffering different stages of AD. We recruited 107 participants including 23 healthy controls (HC), 21 amnestic mild cognitive impairment (aMCI), 24 non-amnestic mild cognitive impairment (naMCI) and 39 AD patients. Via liquid chromatography-mass spectrometry based serum untargeted lipidomics analysis, we compared differences in serum lipid metabolites among these patient groups and further elucidated biomarkers that differentiate aMCI from HC. There were significant differences of serum lipid metabolites among the groups, and 20 metabolites were obtained under negative ion mode from HC and aMCI comparison. Notably, 16:3 cholesteryl ester, ganglioside GM3 (d18:1/9z-18:1) and neuromedin B were associated with cognition and increased the predictive effect of aMCI to 0.98 as revealed by random forest classifier. The prediction model composed of MoCA score, 16:3 cholesteryl ester and ganglioside GM3 (d18:1/9z-18:1) had good predictive performance for aMCI. Glycerophospholipid metabolism was a pathway common among HC/aMCI and aMCI/AD groups. This study provides preliminary evidence highlighting that 16:3 cholesteryl ester were useful for AD disease monitoring while ganglioside GM3 (d18:1/9z-18:1) and neuromedin B discriminated aMCI from HC, which can probably be applied in clinic for early predicting of AD.
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http://dx.doi.org/10.3389/fneur.2021.704582DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8365883PMC
August 2021

Focus on the Beauty of Body: The Mediation Role of Body Appreciation Between Perfectionism and Body-Related Shame and Body-Related Guilt.

Front Psychol 2021 26;12:638641. Epub 2021 Jul 26.

Beijing Key Laboratory of Applied Experimental Psychology, Faculty of Psychology, Beijing Normal University, Beijing, China.

: According to traditional views, perfectionists are prone to experience shame and guilt. As a relative part of negative body image, body appreciation reflects an appreciation attitude toward physical characteristics, functionality, and health, accepting and appreciating all parts and functions of the body, predicting body-related shame and guilt. : Therefore, body appreciation was examined for its potential mediating role in the relationship between two dimensions of perfectionism (e.g., healthy perfectionism and unhealthy perfectionism) and body-related shame and body-related guilt among 514 females. The results highlight that body appreciation partially mediated the relationship between perfectionism and body-related shame and body-related guilt. Implications for enhancing body appreciation among females between experiencing healthy or unhealthy perfectionism and body-related shame and body-related guilt feelings are discussed. : These findings underscore the importance of considering body appreciation in addressing perfectionism dimensions and body-related shame and body-related guilt. Research and clinical implications are also addressed.
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http://dx.doi.org/10.3389/fpsyg.2021.638641DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8366495PMC
July 2021

Nonprecious bimetallic Fe, Mo-embedded N-enriched porous biochar for efficient oxidation of aqueous organic contaminants.

J Hazard Mater 2021 Jul 29;422:126776. Epub 2021 Jul 29.

School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia. Electronic address:

Bimetallic Fe- and Mo-embedded N-enriched porous biochar ([email protected]) is developed and serves as a cost-effective and highly efficient catalyst for mineralization of non-biodegradation organic contaminants. [email protected] was prepared by pyrolysis of complex Fe/Mo -containing precursors. Transmission electron microscopy and elemental mapping suggested that Fe and Mo are uniformly dispersed in nitrogen-doped biochar with hierarchical mesopores. In comparison to [email protected] and [email protected], [email protected] exhibited a superior activity for activating peroxymonosulfate (PMS). The stable activity was ascribed to N-doping and synergistic effect of Fe and Mo species, where both Fe-N and Mo-N can simultaneously serve as the active sites and N-BC can act as a carrier and an activator as well as an electron mediator. Electron paramagnetic resonance and quenching experiments indicated that HO, O and O were responsible for organic degradation. The effects of PMS dosage, initial Orange II concentration, temperature, solution pH, coexisting anions and humic acids on organic degradation were also investigated. With the assistance of an external magnet, [email protected] can be easily separated after reaction and remains stable in the reusability tests. This work demonstrates a feasible strategy towards the fabrication of Fe, Mo-embedded N-enriched porous biochar catalysts for the detoxification of organic contaminants.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126776DOI Listing
July 2021

Hepatitis E virus infection activates NLRP3 inflammasome antagonizing interferon response but therapeutically targetable.

Hepatology 2021 Aug 15. Epub 2021 Aug 15.

Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center, Rotterdam, The Netherlands.

Background & Aims: Hepatitis E virus (HEV) infection is the most common cause of liver inflammation, but the pathogenic mechanisms remain largely unclear. We aim to explore whether HEV infection activates inflammasomes, the crosstalk with antiviral interferon response and potential of therapeutic targeting.

Approach & Results: We measured IL-1β secretion, the hallmark of inflammasome activation, in serum of HEV-infected patients and rabbits, and in cultured macrophage cell lines and primary monocyte-derived macrophages. We found that genotypes 3 and 4 HEV infection in rabbits elevated IL-1β production. A profound increase of IL-1β secretion was further observed in HEV-infected patients (1733 pg/mL ± 1234; n = 70) compared with healthy individuals (731 pg/mL ± 701; n = 70). As macrophages are the drivers of inflammatory response, we found inoculation with infectious HEV particles robustly triggered NLRP3 inflammasome activation in primary macrophages and macrophage cell lines. We further revealed that the ORF2 capsid protein and the formed integral viral particles are responsible for activating inflammasome response. We also identified NF-κB signaling activation as a key upstream event of HEV-induced NLRP3 inflammasome response. Interestingly, inflammasome activation antagonizes interferon response to facilitate viral replication in macrophages. Pharmacological inhibitors and clinically used steroids can effectively target inflammasome activation. Combining steroids with ribavirin simultaneously inhibit HEV and inflammasome response without cross-interference.

Conclusions: HEV infection strongly activates NLRP3 inflammasome activation in macrophages, which regulates host innate defense and pathogenesis. Therapeutic targeting NLRP3, in particular when combined with antiviral agents, represents a viable option for treating severe HEV infection.
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http://dx.doi.org/10.1002/hep.32114DOI Listing
August 2021

Dissolved oxygen disturbs nitrate transformation by modifying microbial community, co-occurrence networks, and functional genes during aerobic-anoxic transition.

Sci Total Environ 2021 Oct 8;790:148245. Epub 2021 Jun 8.

School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an 710129, China.

No consensus has been achieved among researchers on the effect of dissolved oxygen (DO) on nitrate (NO-N) transformation and the microbial community, especially during aerobic-anoxic transition. To supplement this knowledge, NO-N transformation, microbial communities, co-occurrence networks, and functional genes were investigated during aerobic-anoxic transition via microcosm simulation. NO-N transformation rate in the early stage (DO ≥2 mg/L) was always significantly higher than that in the later stage (DO <2 mg/L) during aerobic-anoxic transition, and NO-N accumulation was more significant during the anoxic stage, consistent with the result obtained under constant DO conditions. These NO-N transformation characteristics were not affected by other environmental factors, indicating the important role of DO in NO-N transformation during aerobic-anoxic transition. Changes in DO provoked significant alterations in microbial diversity and abundance of functional bacteria dominated by Massilia, Bacillus, and Pseudomonas, leading to the variation in NO-N transformation. Co-occurrence network analysis revealed that NO-N transformation was performed by the interactions between functional bacteria including symbiotic and competitive relationship. In the presence of oxygen, these interactions accelerated the NO-N transformation rate, and bacterial metabolization proceeded via increasingly varied pathways including aerobic and anoxic respiration, which was demonstrated through predicted genes. The higher relative abundance of genes narG, narH, and napA suggested the occurrence of coupled aerobic-anoxic denitrification in the early stage. NO-N transformation rate decreased accompanied by a significant NO-N accumulation with the weakening of coupled aerobic-anoxic denitrification during aerobic-anoxic transition. Structural equation modeling further demonstrated the relationship between DO and NO-N transformation. DO affects NO-N transformation by modifying microbial community, bacterial co-occurrence, and functional genes during aerobic-anoxic transition.
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http://dx.doi.org/10.1016/j.scitotenv.2021.148245DOI Listing
October 2021

The impact of COVID-19 pandemic on HIV care continuum in Jiangsu, China.

BMC Infect Dis 2021 Aug 7;21(1):768. Epub 2021 Aug 7.

Institute for STI and HIV Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, No. 172 Jiangsu Road, Gulou District, Nanjing, 21009, Jiangsu, China.

Background: The COVID-19 pandemic seriously threatens general public health services globally. This study aimed to evaluate the impact of the COVID-19 pandemic on the HIV care continuum in Jiangsu province, China.

Methods: Data on newly diagnosed HIV persons for analysis were retrieved from Chinas' web-based Comprehensive Response Information Management System (CRIMS) for HIV/AIDS from 2016 to 2020. We recorded data for the first 3 months (January to March, 2020) of strictly implementing COVID-19 measures from publicly available disease databases of the Jiangsu provincial Health Committee. We used seasonal autoregressive integrated moving average (SARIMA) and exponential smoothing in forecasting the parameters. Subgroup differences were accessed using Chi-square tests.

Results: Compared to the estimated proportions, the HIV testing rates decreased by 49.0% (919,938) in the first three months of implementing COVID-19 measures. Of an estimated 1555 new HIV diagnosis expected in the same period, only 63.0% (980) new diagnoses were recorded. According to actual data recorded during the said period, 980 positively tested persons received confirmatory tests, of which 71.4% (700) were reportedly linked to care. And only 49.5% (235) out of the expected 475 newly diagnosed HIV persons received CD4 cell count testing. Meanwhile 91.6% (208) of newly diagnosed HIV persons who received CD4 count tests reportedly initiated antiretroviral therapy (ART) compared to the 227 expected. Compared to the same period from 2016 to 2019, PLWH less than 30 years old and migrants were more likely to be affected by the COVID-19 policies.

Conclusions: The COVID-19 pandemic negatively impacted HIV healthcare systems in Jiangsu, China. Further measures that can counter the impact of the pandemic are needed to maintain the HIV care continuum.
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http://dx.doi.org/10.1186/s12879-021-06490-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8346346PMC
August 2021

Phosphorus coordinated Rh single-atom sites on nanodiamond as highly regioselective catalyst for hydroformylation of olefins.

Nat Commun 2021 Aug 4;12(1):4698. Epub 2021 Aug 4.

Engineering Center of Catalysis and Synthesis for Chiral Molecules, Department of Chemistry, Fudan University, Shanghai, China.

Single-atom Rh catalysts present superior activity relative to homogeneous catalyst in olefins hydroformylation, yet with limited success in regioselectivity control. In the present work, we develop a phosphorus coordinated Rh single-atom catalyst with nanodiamond as support. Benefiting from this unique structure, the catalyst exhibits excellent activity and regioselectivity in hydroformylation of arylethylenes with wide substrate generality, i.e., with high conversion (>99%) and high regioselectivity (>90%), which is comparable with the homogeneous counterparts. The coordination interaction between Rh and surface phosphorus species is clarified by P solid-state NMR and X-ray absorption spectroscopy (XAS). Rh single atoms are firmly anchored over nanodiamond through Rh-P bonds, guaranteeing good stability in the hydroformation of styrene even after six runs. Finally, by using this catalyst, two kinds of pharmaceutical molecules, Ibuprofen and Fendiline, are synthesized efficiently with high yields, demonstrating a new prospect of single-atom catalyst in pharmaceutical synthesis.
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http://dx.doi.org/10.1038/s41467-021-25061-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8339002PMC
August 2021

A fluorescent and colorimetric dual-channel sensor based on acid phosphatase-triggered blocking of internal filtration effect.

Mikrochim Acta 2021 08 2;188(8):282. Epub 2021 Aug 2.

State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.

A colorimetric and fluorescent dual-channel detection method for acid phosphatase (ACP) activity has been constructed, based on the internal filtering effect between oxidized 3,3',5,5'-tetramethylbenzidine (oxTMB) and rhodamine B (RB). Au, which in situ form gold nanoparticles (AuNPs), can oxidize colorless 3,3',5,5'-tetramethylbenzidine (TMB) to oxTMB (blue color). The fluorescence of RB can be quenched by oxTMB due to the spectral overlap of emission of RB and absorption of oxTMB. By means of the above process, ACP can be determined because ACP promotes the hydrolysis of 2-phospho-L-ascorbic acid trisodium salt (AAP) to generate ascorbic acid (AA), which can inhibit the internal filtering effect between RB and oxTMB. No material preparation was needed for the determination of ACP. The colorimetric and fluorimetric methods can quantify ACP in the range 0.06-5.0 mU/mL and 0.03-5.0 mU/mL, respectively. Furthermore, a smartphone-assisted sensing platform has been constructed for on-site monitoring of ACP in the range 0.75-50 mU/mL, and the detection limit is 0.3 mU/mL. The methods developed can measure ACP in human serum successfully.
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http://dx.doi.org/10.1007/s00604-021-04951-6DOI Listing
August 2021

A novel green substrate made by sludge digestate and its biochar: Plant growth and greenhouse emission.

Sci Total Environ 2021 Jul 21;797:149194. Epub 2021 Jul 21.

College of Life and Environment Science, Wenzhou University, Wenzhou 325035, China.

Anaerobic digestion of sludge produces a large amount of sewage sludge anaerobic digestate (SSAD) that can be reused. A novel green substrate was prepared by mixing SSAD and its biochar (SSBC) filled with perlite and quartz sand for plant growth, as a replacement of soil. We carried out pot experiment, measured ryegrass biomass, seedling survival rate, and evaluated the emission of greenhouse gas (GHG), NH volatilization. The results showed that the seedling survival rate and individual biomass of ryegrass in green substrate were 100% and 100.02 mg, which were 14.4% and 231.4% higher than those in only SSAD, but were 1.3% and 19.6% higher than those in soil. SSBC significantly reduced NO and CO emission, inhibited the NH volatilization, but increased CH emission. However, the cumulative emission of NO and CH was approximation to that in soil. Global warming potential of CH and NO (GWP) green substrate was 11,842.01 kg CO·hm, which was 1.35-fold higher than that of soil. Microbial community structure analysis showed that fermentative bacteria and methanogenic archaeal had a higher abundance in green substrate than in soil, which caused the different gas emission. This study will provide an effective and economical way to dispose excessive SSAD.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149194DOI Listing
July 2021

Effect of cardiopulmonary rehabilitation nursing on exercise endurance and quality of life of stable COPD patients.

Am J Transl Res 2021 15;13(6):7356-7362. Epub 2021 Jun 15.

Department II of Respiratory and Critical Care Medicine, Cangzhou Central Hospital Cangzhou, China.

Objective: To investigate the effect of cardiopulmonary rehabilitation nursing on exercise endurance and quality of life (QOL) of patients with stable chronic obstructive pulmonary disease (COPD).

Methods: This randomized trial was conducted on 84 subjects with stable COPD recruited in our hospital from March 2018 to December 2019 and they were divied into the observation group (n=42) and the control group (n=42) based on nursing methods. The control group adopted conventional nursing, and the observation group received cardiopulmonary rehabilitation nursing in addition to conventional method. The exercise endurance, cardiopulmonary function, psychological state, QOL and nursing satisfaction were compared at pre- and post-nursing care.

Results: Before nursing, no notable difference was observed in 6 min walking distance (6MWD), deep inspiratory volume (IC), left ventricular ejection fraction (LVEF), forced vital capacity (FVC), Forced expiratory volume in one second (FEV1), FEV1/FVC, Self-Rating Anxiety Scale (SAS), Self-rating Depression Scale (SDS) score, QOL, scores of symptoms, activities and impact in these two groups (P>0.05). After nursing, 6MWD and IC of observation group were remarkably higher (P<0.05); LVEF, FVC, FEV1 and FEV1/FVC in the observation group were remarkably higher (P<0.05); SAS and SDS scores of two groups decreased, and the observation group was notably lower (P<0.05); the QOL scores of symptoms, activities and effects of two groups were notably reduced, and the observation group was remarkably lower (P<0.05). The nursing satisfaction of the observation group was considerably higher than the control group (95.23% vs 76.19%) (P<0.05).

Conclusion: Cardiopulmonary rehabilitation nursing has a remarkable effect on COPD patients in stable stage, which can enhance patients' exercise endurance and lung function, reduce adverse emotions, and improve patients' QOL and nursing satisfaction.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8290647PMC
June 2021

Effect of psychological intervention care on the negative mood and hope level of elderly patients undergoing knee arthroplasty.

Authors:
Jing Yu Xiaoyan Liu

Am J Transl Res 2021 15;13(6):6584-6591. Epub 2021 Jun 15.

Department of Orthopedic, West China School of Nursing/West China Hospital Orthopedic Department, Sichuan University Chengdu, Sichuan Province, China.

Objective: We explored the influence of psychological intervention care on the negative mood and hope level of elderly patients undergoing knee arthroplasty.

Methods: A total of 98 elderly patients undergoing knee arthroplasty in our hospital were randomly divided into a control group and an observation group, each with 49 people. The control group was given routine nursing care, and the observation group was given psychological intervention care plus routine nursing care. In the study, we compared the negative mood (Emotional distress Index Scale), preoperative hope level, quality of life, Range of Motion (ROM) of the knee, score of Hospital for Special Surgery (HSS), and satisfaction in the two groups of patients.

Results: Patients in the observation group had lower Xinqing index scores than the control group (P<0.001). The scores of preoperative hope level in the observation group were higher than those of the control group (P<0.001). The scores of physical function, general health, social function, emotional role, and mental health were higher in the observation group than in the control group (all P<0.01). The ROM scores of patients in the observation group were higher than those of the control group (P<0.001). The HSS scores of patients in the observation group were higher than those of the control group (P<0.001). The patients in the observation group were significantly more satisfied with the care during hospitalization than the control group.

Conclusion: Psychological intervention care was effective for elderly patients undergoing knee arthroplasty. It could improve patients' negative mood, hope level, quality of life, and rehabilitation effects, and is worthy of clinical promotion and application.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8290676PMC
June 2021

Metformin inhibits MAPK signaling and rescues pancreatic aquaporin 7 expression to induce insulin secretion in type 2 diabetes mellitus.

J Biol Chem 2021 Aug 22;297(2):101002. Epub 2021 Jul 22.

Department of Anatomy, College of Basic Medicine, Chongqing Medical University, Chongqing, People's Republic of China. Electronic address:

Metformin is the first-line antidiabetic agent for type 2 diabetes mellitus (T2DM) treatment. Although accumulated evidence has shed light on the consequences of metformin action, the precise mechanisms of its action, especially in the pancreas, are not fully understood. Aquaporin 7 (AQP7) acts as a critical regulator of intraislet glycerol content, which is necessary for insulin production and secretion. The aim of this study was to investigate the effects of different doses of metformin on AQP7 expression and explore the possible mechanism of its protective effects in the pancreatic islets. We used an in vivo model of high-fat diet in streptozocin-induced diabetic rats and an in vitro model of rat pancreatic β-cells (INS-1 cells) damaged by hyperglycemia and hyperlipidemia. Our data showed that AQP7 expression levels were decreased, whereas p38 and JNK mitogen-activated protein kinases (MAPKs) were activated in vivo and in vitro in response to hyperglycemia and hyperlipidemia. T2DM rats treated with metformin demonstrated a reduction in blood glucose levels and increased regeneration of pancreatic β-cells. In addition, metformin upregulated AQP7 expression as well as inhibited activation of p38 and JNK MAPKs both in vivo and in vitro. Overexpression of AQP7 increased glycerol influx into INS-1 cells, whereas inhibition of AQP7 reduced glycerol influx, thereby decreasing subsequent insulin secretion. Our findings demonstrate a new mechanism by which metformin suppresses the p38 and JNK pathways, thereby upregulating pancreatic AQP7 expression and promoting glycerol influx into pancreatic β-cells and subsequent insulin secretion in T2DM.
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http://dx.doi.org/10.1016/j.jbc.2021.101002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8374641PMC
August 2021

A Soft and Absorbable Temporary Epicardial Pacing Wire.

Adv Mater 2021 Sep 24;33(36):e2101447. Epub 2021 Jul 24.

Shenzhen Key Laboratory of Smart Healthcare Engineering, Department of Biomedical Engineering, Southern University of Science and Technology, No. 1088, Xueyuan Rd., Xili, Nanshan District, Shenzhen, Guangdong, 518055, P. R. China.

Existing temporary epicardial pacing wires (TPWs) are rigid and non-absorbable, such that they can cause severe complications after cardiac surgery. Here, a soft and absorbable temporary epicardial pacing wire (saTPW) for effectively correcting abnormal heart rates in a rabbit model, such as bradycardia and ventricular premature beat, is developed. The saTPW exhibits excellent conductivity, flexibility, cycling stability (>100 000 cycles), and less inflammatory response during two-month subcutaneous implantation in a rat model. The saTPW which consists of poly(l-lactide-co-ε-caprolactone) and liquid metal, can degrade about 13% (mass loss) in the rats over a two-month subcutaneous implantation. It can be absorbed over time in the body. The cytocompatibility and absorbability avoid secondary injuries caused by remaining wires which are permanently left in the body. The saTPW will provide a great platform for diagnosis and treatments in cardiovascular diseases by delivering the physiological signal and applying electrical stimulation for therapy.
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http://dx.doi.org/10.1002/adma.202101447DOI Listing
September 2021

Acquired Perforating Dermatosis Induced by PD-1 Inhibitor: A Case Report.

Am J Dermatopathol 2021 Jul 20. Epub 2021 Jul 20.

Department of Dermatology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China; Department of Dermatology, Affiliated Hospital of Chengde Medical College; Department of Biology, Providence College, Providence, RI; and Ackerman Academy of Dermatopathology, New York, NY.

Abstract: Acquired perforating dermatoses (APDs) are a group of diverse skin disorders in patients with systemic disease, most commonly chronic renal failure and diabetes mellitus. APD induced by medication has seldom been reported. Anti-PD-1 monoclonal antibody has recently been used as a broad-spectrum, effective, durable, and relatively safe antitumor therapy for various malignancies. Thus far, known side effects involving skin have included rash, pruritus, and vitiligo. Here, we present a rare case of a unilateral linear eruption with histopathologic features of APD in a 36-year-old man during treatment with Terepril monoclonal antibody. To the best of our knowledge, APD induced by the PD-1 inhibitor has not been described in the medical literature.
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http://dx.doi.org/10.1097/DAD.0000000000002026DOI Listing
July 2021

Atomic Pyridinic Nitrogen Sites Promoting Levulinic Acid Hydrogenations over Double-Shelled Hollow Ru/C Nanoreactors.

Small 2021 Aug 12;17(33):e2101271. Epub 2021 Jul 12.

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian, 116023, China.

Nitrogen-doped nanocarbons are widely used as supports for metal-heterogeneous catalytic conversions. When nitrogen-doped nanocarbon supports are used to disperse metallic nanoparticles (MNPs), the nitrogen dopant can enhance MNPs electron density to reach higher catalytic activity and promote MNPs stability through anchoring effects. However, the precise identification of active nitrogen species between N-dopants and reactants is rarely reported. Herein, a proof-of-concept study on the active N species for levulinic acid hydrogenation is reported. A double-shell structured carbon catalyst (DSC) is designed with selectively locating ultrafine Ru NPs only on inner carbon shell, specifically, different N species on the external carbon shell. Through the design of such a nanostructure, it is demonstrated that the alkaline pyridinic N species on the outer shell serves as an anchor point for the spontaneous binding of the acidic reactant. The pyridinic N content can be modulated from 7.4 to 29.2 mg g by selecting different precursors. Finally, the Ru-DSC-CTS (using chitosan as the precursor) catalyst achieves a 99% conversion of levulinic acid under 70 °C and 4 MPa hydrogen pressure for 1 h. This work sheds light on the design of nanoreactors at the atomic scale and investigates heterogeneous catalysis at the molecular level.
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http://dx.doi.org/10.1002/smll.202101271DOI Listing
August 2021
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