Publications by authors named "Yu Shen"

742 Publications

Evolutionary coupling-inspired engineering of alcohol dehydrogenase reveals the influence of distant sites on its catalytic efficiency for stereospecific synthesis of chiral alcohols.

Comput Struct Biotechnol J 2021 26;19:5864-5873. Epub 2021 Oct 26.

Lab of Brewing Microbiology and Applied Enzymology, School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi 214122, China.

Alcohol dehydrogenase (ADH) has attracted much attention due to its ability to catalyze the synthesis of important chiral alcohol pharmaceutical intermediates with high stereoselectivity. ADH protein engineering efforts have generally focused on reshaping the substrate-binding pocket. However, distant sites outside the pocket may also affect its activity, although the underlying molecular mechanism remains unclear. The current study aimed to apply evolutionary coupling-inspired engineering to the ADH CpRCR and to identify potential mutation sites. Through conservative analysis, phylogenic analysis and residues distribution analysis, the co-evolution hotspots Leu34 and Leu137 were confirmed to be highly evolved under the pressure of natural selection and to be possibly related to the catalytic function of the protein. Hence, Leu34 and Leu137, far away from the active center, were selected for mutation. The generated CpRCR-L34A and CpRCR-L137V variants showed high stereoselectivity and 1.24-7.81 fold increase in value compared with that of the wild type, when reacted with 8 aromatic ketones or -ketoesters. Corresponding computational study implied that L34 and L137 may extend allosteric fluctuation in the protein structure from the distal mutational site to the active site. Moreover, the L34 and L137 mutations modified the pre-reaction state in multiple ways, in terms of position of the hydride with respect to the target carbonyl. These findings provide insights into the catalytic mechanism of the enzyme and facilitate its regulation from the perspective of the site interaction network.
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http://dx.doi.org/10.1016/j.csbj.2021.10.031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8572861PMC
October 2021

A phase II study of talimogene laherparepvec for patients with inoperable locoregional recurrence of breast cancer.

Sci Rep 2021 Nov 15;11(1):22242. Epub 2021 Nov 15.

Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd., Unit 1354, Houston, TX, 77030, USA.

Talimogene laherparepvec (T-VEC) is an immunotherapy that generates local tumor lysis and systemic antitumor immune response. We studied the efficacy of intratumoral administration of T-VEC as monotherapy for inoperable locoregional recurrence of breast cancer. T-VEC was injected intratumorally at 10 PFU/mL on day 1 (cycle 1), 10 PFU/mL on day 22 (cycle 2), and 10 PFU/mL every 2 weeks thereafter (cycles ≥ 3). Nine patients were enrolled, 6 with only locoregional disease and 3 with both locoregional and distant disease. No patient completed the planned 10 cycles or achieved complete or partial response. The median number of cycles administered was 4 (range, 3-8). Seven patients withdrew prematurely because of uncontrolled disease progression, 1 withdrew after cycle 3 because of fatigue, and 1 withdrew after cycle 4 for reasons unrelated to study treatment. Median progression-free survival and overall survival were 77 days (95% CI, 63-NA) and 361 days (95% CI, 240-NA). Two patients received 8 cycles with clinically stable disease as the best response. The most common grade 2 or higher adverse event was injection site reaction (n = 7, 78%). Future studies could examine whether combining intratumoral T-VEC with concurrent systemic therapy produces better outcomes.
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http://dx.doi.org/10.1038/s41598-021-01473-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8593093PMC
November 2021

MicroRNA Variants and HLA-miRNA Interactions are Novel Rheumatoid Arthritis Susceptibility Factors.

Front Genet 2021 29;12:747274. Epub 2021 Oct 29.

Department of Rheumatology,Guanghua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China.

Genome-wide association studies have identified >100 genetic risk factors for rheumatoid arthritis. However, the reported genetic variants could only explain less than 40% heritability of rheumatoid arthritis. The majority of the heritability is still missing and needs to be identified with more studies with different approaches and populations. In order to identify novel function SNPs to explain missing heritability and reveal novel mechanism pathogenesis of rheumatoid arthritis, 4 HLA SNPs (, , and ) and 225 common SNPs located in miRNA, which might influence the miRNA target binding or pre-miRNA stability, were genotyped in 1,607 rheumatoid arthritis and 1,580 matched normal individuals. We identified 2 novel SNPs as significantly associated with rheumatoid arthritis including rs1414273 (, OR = 0.84, = 8.26 × 10) and rs2620381 ( OR = 0.77, = 2.55 × 10). We also identified that rs5997893 () showed significant epistasis effect with rs4947332 (, OR = 4.23, = 0.04) and rs2967897 (miR-5695) with rs7752903 (, OR = 4.43, = 0.03). In addition, we found that individuals who carried 8 risk alleles showed 15.38 (95%CI: 4.69-50.49, < 1.0 × 10) times more risk of being affected by RA. Finally, we demonstrated that the targets of the significant miRNAs showed enrichment in immune related genes ( = 2.0 × 10) and FDA approved drug target genes ( = 0.014). Overall, 6 novel miRNA SNPs including rs1414273 (, = 8.26 × 10), rs2620381 (, = 2.55 × 10), rs4285314 (miR-3135b, = 1.10 × 10), rs28477407 (miR-4308, = 3.44 × 10), rs5997893 (, = 5.9 × 10) and rs45596840 (, = 6.6 × 10) were confirmed to be significantly associated with RA in a Chinese population. Our study suggests that miRNAs might be interesting targets to accelerate understanding of the pathogenesis and drug development for rheumatoid arthritis.
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http://dx.doi.org/10.3389/fgene.2021.747274DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8585984PMC
October 2021

Legacy organochlorines in estuarine sediment in relation to socioeconomic pattern in multi-coastal watersheds.

Environ Sci Pollut Res Int 2021 Nov 13. Epub 2021 Nov 13.

CAS Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 361021, China.

Estuarine sediment quality is highly associated with anthropogenic activities in watersheds. This study attempts to couple socioeconomic patterns with estuarine sediment quality via legacy organochlorines in 14 Chinese coastal watersheds. Sedimentary concentrations of HCHs, DDTs, and PCBs showed a significant spatiality in estuary, up to 48.7 ± 15.1, 89.0 ± 46.4, and 54.5 ± 17.2 ng g, which were predominated by β-HCH, p,p'-DTs, and tri- to penta-PCBs, respectively. Ecological risk of organochlorines was negligible except few moderate risks for DDTs and PCBs against the first class quality of the marine sediment quality guidelines of China. Sedimentary DDT and PCB concentrations were significantly delineated by an environmental Kuznets curve model as a function of non-agricultural GDP per capita in watersheds, while HCHs by an increasing linear model. Findings of this study provide a tool to quantify the contribution of anthropogenic development in watershed to environmental change in estuary across the world.
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http://dx.doi.org/10.1007/s11356-021-17350-4DOI Listing
November 2021

Microplastics lag the leaching of phenanthrene in soil and reduce its bioavailability to wheat.

Environ Pollut 2022 Jan 6;292(Pt B):118472. Epub 2021 Nov 6.

College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province, 210095, People's Republic of China. Electronic address:

Microplastics wildly occur in soil and they can become the carriers of persistent contaminants. However, the influence of microplastics on polycyclic aromatic hydrocarbons vertical translocation in the soil system after rainfall is limitedly understood. Here, experiments were conducted to study the influence of polyethylene (PE), polystyrene (PS) and polyvinyl chloride (PVC) microplastics on the leaching behavior and bioavailability of phenanthrene (Phe). The adsorption capacity of phenanthrene on the microplastics followed the order of PS > PE > PVC. The Phe concentrations in the top soil layer after 15 days of leaching with water were 30.25, 28.32 and 27.25 mg kg for the treatments of Phe-PS, Phe-PE and Phe-PVC respectively, which is consistent with the adsorption capacities of microplastics. The concentrations of Phe were correlated with the microplastic adsorption capacities at soil depths of 5-45 cm. Under long-term leaching, Phe could reach the deeper soil layer. Phe concentrations significantly decreased in the leachate over time. Phe concentrations in wheat had a positive correlation with that in leachate/leached top soil layer. Our findings are beneficial to accurately evaluate the ecological risk of the combined contamination of PAHs and microplastics, and improve the understanding of the environmental behaviors of different microplastics.
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http://dx.doi.org/10.1016/j.envpol.2021.118472DOI Listing
January 2022

ESTROGEN RECEPTOR EXPRESSION ON BREAST CANCER PATIENTS' SURVIVAL UNDER SHAPE RESTRICTED COX REGRESSION MODEL.

Ann Appl Stat 2021 Sep;15(3):1291-1307

Department of Biostatistics, University of Texas MD Anderson Cancer Center.

For certain subtypes of breast cancer, study findings show that their level of estrogen receptor expression is associated with their risk of cancer death, and also suggests a non-linear effect on the hazard of death. A flexible form of the proportional hazards model, (∣ ) = () exp( )(), is desirable to facilitate a rich class of covariate effect on a survival outcome to provide meaningful insight, where the functional form of () is not specified except for its shape. Prior biologic knowledge on the shape of the underlying distribution of the covariate effect in regression models can be used to enhance statistical inference. Despite recent progress, major challenges remain for the semiparametric shape-restricted inference due to lack of practical and efficient computational algorithms to accomplish non-convex optimization. We propose an alternative algorithm to maximize the full log-likelihood with two sets of parameters iteratively under monotone constraints. The first set consists of the non-parametric estimation of the monotone-restricted function (), while the second set includes estimating the baseline hazard function and other covariate coefficients. The iterative algorithm in conjunction with the pool-adjacent-violators algorithm makes the computation efficient and practical. The Jackknife resampling effectively reduces the estimator bias, when sample size is small. Simulations show that the proposed method can accurately capture the underlying shape of (), and outperforms the estimators when () in the Cox model is mis-specified. We apply the method to model the effect of estrogen receptor on breast cancer patients' survival.
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http://dx.doi.org/10.1214/21-aoas1446DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8570133PMC
September 2021

Design and engineering of whole-cell biocatalyst for efficient synthesis of (R)-citronellal.

Microb Biotechnol 2021 Nov 2. Epub 2021 Nov 2.

State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, China.

Bioproduction of optical pure (R)-citronellal from (E/Z)-citral at high substrate loading remains challenging. Low catalytic efficiency of (R)-stereoselective ene reductases towards crude citral mixture is one of the major bottlenecks. Herein, a structure-based engineering strategy was adopted to enhance the catalytic efficiency and stereoselectivity of an ene reductase (OYE2p) from Saccharomyces cerevisiae YJM1341 towards (E/Z)-citral. On basis of homologous modelling, molecular docking analysis and alanine scanning at the binding pocket of OYE2p, a mutant Y84A was obtained with simultaneous increase in catalytic efficiency and stereoselectivity. Furthermore, site-saturation mutagenesis of Y84 yielded seven mutants with improved activity and stereoselectivity in the (E/Z)-citral reduction. Among them, the variant Y84V exhibited an 18.3% and 71.3% rise in catalytic efficiency (k /K ) for (Z)-citral and (E)-citral respectively. Meanwhile, the stereoselectivity of Y84V was improved from 89.2% to 98.0% in the reduction in (E/Z)-citral. The docking analysis and molecular dynamics simulation of OYE2p and its variants revealed that the substitution Y84V enabled (E)-citral and (Z)-citral to bind with a smaller distance to the key hydrogen donors at a modified (R)-selective binding mode. The variant Y84V was then co-expressed with glucose dehydrogenase from Bacillus megaterium in E. coli D4, in which competing prim-alcohol dehydrogenase genes were deleted to prevent the undesired reduction in the aldehyde moiety of citral and citronellal. Employing this biocatalyst, 106 g l (E/Z)-citral was completely converted into (R)-citronellal with 95.4% ee value and a high space-time yield of 121.6 g l  day . The work highlights the synthetic potential of Y84V, which enabled the highest productivity of (R)-citronellal from (E/Z)-citral in high enantiopurity so far.
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http://dx.doi.org/10.1111/1751-7915.13958DOI Listing
November 2021

Treatment Strategies for Cryptogenic Stroke Patients with Patent Foramen Ovale: What Do We Choose?

Neuropsychiatr Dis Treat 2021 22;17:3205-3214. Epub 2021 Oct 22.

Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.

Importance: The treatment of cryptogenic stroke patients with patent foramen ovale to prevent recurrence of stroke, especially when patients consider drug prevention alone, has caused serious treatment dilemmas in clinical practice.

Objective: To study the safety and efficacy of different treatment strategies using a network meta-analysis of randomized controlled trials in this population with cryptogenic stroke and patent foramen ovale.

Study Selection: PUBMED, EMBASE, The Cochrane Library, WangFang, and China National Knowledge Infrastructure were searched to identify RCT comparing different treatment strategies. Eleven randomized studies were included (n = 5706).

Main Outcomes: The primary efficacy outcome was recurrence of ischemic stroke, including fatal and non-fatal ischemic strokes. The primary safety outcome was major hemorrhage, but closure surgery includes systemic thrombotic events, persistent atrial fibrillation, surgical deaths and other major events.

Results: In terms of efficacy and safety events, compared with antiplatelet, the OR of vitamin K antagonists for stroke recurrence was 0.81 (95% CI, 0.41-1.6), the OR of surgical closure was 0.38 (95% CI, 0.16-0.63), and the OR of NOAC was 0.79 (95% CI, 0.27-2.3). Compared with antiplatelet, the safety event OR of vitamin K antagonists was 1.7 (95% CI, 0.65-4.8), the OR of surgical closure was 1.7 (95% CI, 0.68-3.8), and the OR of NOAC was 2.2 (95% CI, 0.67-7.6).

Conclusion: In terms of effectiveness, surgical occlusion has the best performance, while anticoagulation is the second best. Vitamin K antagonists and non-vitamin K antagonists are difficult to distinguish between the best in effectiveness. Antiplatelet drugs are considered the worst option. Regarding the safety results, it is generally believed that there are no obvious beneficial interventions, but antiplatelet drugs are considered to be relatively best, followed by surgical intervention and vitamin K antagonists, and non-vitamin K antagonists are considered to be the least safe.
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http://dx.doi.org/10.2147/NDT.S333930DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8548060PMC
October 2021

Comparative analysis of membrane fouling mechanisms induced by colloidal polymer: Effects of sodium and calcium ions.

J Colloid Interface Sci 2021 Oct 13;608(Pt 1):780-791. Epub 2021 Oct 13.

School of Environmental and Ecology, Chongqing University, Chongqing 400044, China.

Polymer (anionic polyacrylamide, APAM) flooding produced wastewater has a relatively high degree of mineralization and abundant ionic species. A comprehensive and systematic investigation of the influence of ion identity on APAM-induced membrane fouling is extremely necessary but has not been conducted to date. A comparative investigation was performed herein to reveal the underlying mechanisms of the influence of Na and Ca (1000 mg/L) on APAM-induced membrane fouling in the adsorption and microfiltration (MF) processes. Na and Ca exhibited contrasting influences on the filtration efficiency, cleaning efficiency, and fouling resistance. Compared to Na, Ca promoted reversible fouling and the formation of a loose cake layer; moreover, a higher removal rate and flux recovery were achieved. Additionally, simulations based on adsorption kinetic and membrane fouling models, and a series of microscopic analyses were performed to validate the contradictory influences. During the APAM-based MF process, the membrane fouling was effectively mitigated at the applied ionic strength because of the stronger hydration repulsive force generated by hydrated Ca compared to that by Na. This study provides vital guidance for membrane fouling control in the microfiltration of polymer flooding produced wastewater.
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http://dx.doi.org/10.1016/j.jcis.2021.10.043DOI Listing
October 2021

Dual-site electrocatalytic nitrate reduction to ammonia on oxygen vacancy-enriched and Pd-decorated MnO nanosheets.

Nanoscale 2021 Oct 28;13(41):17504-17511. Epub 2021 Oct 28.

Engineering Research Center for Waste Oil Recovery Technology and Equipment, Ministry of Education, Chongqing Technology and Business University, Chongqing 400067, China.

Electrocatalytic nitrate reduction (NRR) represents one promising alternative to the Haber-Bosch process for NH production due to the lower reaction energy barrier compared to N reduction and the potential recycling of nitrogen source from nitrate wastewater. The metal oxides with oxygen vacancy (O) display high NH selectivities in NRR (NO/N as side products), but the complexity in O enrichment and the inferior hydrogen adsorption on oxides make NRR an inefficient process. Herein, one superior dual-site NRR electrocatalyst that is composed of O-enriched MnO nanosheets (MnO-O) and Pd nanoparticles (deposited on MnO) is constructed over the three-dimensional porous nickel foam (Pd-MnO-O/Ni foam). In a continuous-flow reaction cell, this electrode delivers a NO-N conversion rate of 642 mg N m h and a NH selectivity of 87.64% at -0.85 V Ag/AgCl when feeding 22.5 mg L of NO-N (0.875 mL min), outperforming the Pd/Ni foam (369 mg N m h, 85.02%) and MnO-O/Ni foam (118 mg N m h, 32.25%). Increasing the feeding NO-N concentration and flow rate to 180.0 mg L and 2.81 mL min can further lift the conversion rate to 1933 and 1171 mg N m h, respectively. The combination of experimental characterizations and theoretical calculations reveal that the MnO-O adsorbs, immobilizes, and activates the NO and N-intermediates, while the Pd supplies the O sites with sufficient adsorbed hydrogen (H*) for both the NRR and O refreshment. Our work presents a good example of utilizing dual-site catalysis in the highly selective conversion of NO to NH that is important for nitrate pollution abatement, nitrogen resource recycling, as well as sustainable NH production.
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http://dx.doi.org/10.1039/d1nr04962cDOI Listing
October 2021

Insight into the structure and metabolic function of iron-rich nanoparticles in anammox bacteria.

Sci Total Environ 2021 Oct 8:150879. Epub 2021 Oct 8.

Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China. Electronic address:

Anaerobic ammonium-oxidizing (anammox) bacteria are iron abundant and depend heavily on iron-binding proteins. The iron demand of anammox bacteria is relatively large. However, it still remains some doubts where these large quantities of available iron come from and how they are regulated in anammox bacteria. Herein, iron-rich nanoparticles in anammoxosomes were detected by synchrotron soft X-ray tomography coupled with scanning transmission X-ray microscopy (STXM). The iron-rich nanoparticles were identified as ferric oxide (α-FeO) mineral cores, and the local atomic structure of iron-rich nanoparticles was obtained by X-ray absorption fine-structure (XAFS) spectra. The bacterioferritin of Q1Q315 and Q1Q5F8 were detected by proteomics analysis. On this basis, the metabolic pathway centered on iron-rich nanoparticles was proposed.
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http://dx.doi.org/10.1016/j.scitotenv.2021.150879DOI Listing
October 2021

Bio-inspired dynamic biomolecule assembling for fine regulation of protein activity.

Chem Commun (Camb) 2021 Oct 26;57(85):11205-11208. Epub 2021 Oct 26.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, P. R. China.

A versatile approach for the fine control of DNA-based hierarchical assembly dual stimuli and two assembly strategies is developed. Moreover, with a reasonable design of functional thrombin aptamer structures on the formed DNA nanoassembly, it can achieve precise regulation of thrombin activity.
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http://dx.doi.org/10.1039/d1cc03926aDOI Listing
October 2021

Factors associated with symptomatic intracranial haemorrhage after intravenous thrombolysis in severe white matter lesions: a retrospective analysis.

Postgrad Med J 2021 Oct 5. Epub 2021 Oct 5.

Neurology, Nanchang University Second Affiliated Hospital, Nanchang, Jiangxi, China

Background And Purpose: White matter lesions (WMLs) are thought to cause damage to the blood-brain barrier, thereby aggravating bleeding after intravenous thrombolysis. However, the risk factors for symptomatic cerebral haemorrhage after thrombolysis are still unclear. This study explored the risk factors for bleeding in patients with severe WMLs after intravenous thrombolysis to prevent bleeding as soon as possible.

Methods: A large single-centre observational study conducted a retrospective analysis of intravenous thrombolysis in patients with severe WMLs from January 2018 to March 2021. According to whether symptomatic cerebral haemorrhage occurred, the patients were divided into two groups, and then statistical analysis was performed.

Results: After a retrospective analysis of the data of nearly 1000 patients with intravenous thrombolysis and excluding invalid information, 146 patients were included, of which 23 (15.8%) patients had symptomatic cerebral haemorrhage. Univariate analysis showed that a history of hypertension (20% vs 4.9%, p=0.024), hyperlipidaemia (38.7% vs 9.6%, p<0.001), the National Institutes of Health Stroke Scale (NIHSS) score before thrombolysis (median 17 vs 6, p<0.001), low-density lipoprotein levels (median 2.98 vs 2.44, p=0.011), cholesterol levels (mean 4.74 vs 4.22, p=0.033), platelet count (median 161 vs 191, p=0.031), platelet distribution width (median 15.2 vs 12.1, p=0.001) and sodium ion levels (median 139.81 vs 138.67, p=0.043) were significantly associated with symptomatic cerebral haemorrhage. Further multivariate logistic regression analysis showed that hyperlipidaemia (OR=9.069; 95% CI 2.57 to 32.07; p=0.001) and the NIHSS score before thrombolysis (OR=1.33; 95% CI 1.16 to 1.52; p<0.001) were comprehensive risk factors for symptomatic cerebral haemorrhage.

Conclusion: Hyperlipidaemia and the NIHSS score before thrombolysis are independent risk factors for bleeding after intravenous thrombolysis in patients with severe WMLs. Delaying the onset of white matter and preventing risk factors for bleeding will help improve the prognosis of cerebral infarction and reduce mortality. These risk factors need to be further evaluated in future studies.
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http://dx.doi.org/10.1136/postgradmedj-2021-140886DOI Listing
October 2021

Outcomes After Breast Radiation Therapy in a Diverse Patient Cohort With a Germline BRCA1/2 Mutation.

Int J Radiat Oncol Biol Phys 2021 Oct 3. Epub 2021 Oct 3.

Departments of Radiation Oncology. Electronic address:

Purpose: BRCA1/2 pathogenic variant (PV) mutations confer radiation sensitivity preclinically, but there are limited data regarding breast cancer outcomes after radiation therapy (RT) among patients with documented BRCA1/2 PV mutations versus no PV mutations.

Methods And Materials: This retrospective cohort study included women with clinical stage I-III breast cancer who received definitive surgery and RT and underwent BRCA1/2 genetic evaluation at the The University of Texas MD Anderson Cancer Center. Rates of locoregional recurrence (LRR), disease-specific death (DSD), toxicities, and second cancers were compared by BRCA1/2 PV status.

Results: Of the 2213 women who underwent BRCA1/2 testing, 63% self-reported their race as White, 13.6% as Black/African American, 17.6% as Hispanic, and 5.8% as Asian/American Indian/Alaska Native; 124 had BRCA1 and 100 had BRCA2 mutations; and 1394 (63%) received regional nodal RT. The median follow-up time for all patients was 7.4 years (95% confidence interval [CI], 7.1-7.7 years). No differences were found between the groups with and without BRCA1/2 PV mutations in 10-year cumulative incidences of LRR (with mutations: 11.6% [95% CI, 7.0%-17.6%]; without mutations: 6.6% [95% CI, 5.3%-8.0%]; P = .466) and DSD (with mutations: 12.3% [95% CI, 8.0%-17.7%]; without mutations: 13.8% [95% CI, 12.0%-15.8%]; P = .716). On multivariable analysis, BRCA1/2 status was not associated with LRR or DSD, but Black/African American patients (P = .036) and Asians/American Indians/Alaska Native patients (P = .002) were at higher risk of LRR compared with White patients, and Black/African American patients were at higher risk of DSD versus White patients (P = .004). No in-field, nonbreast second cancers were observed in the BRCA1/2 PV group. Rates of acute and late grade ≥3 radiation-related toxicity in the BCRA1/2 PV group were 5.4% (n = 12) and 0.4% (n = 1), respectively.

Conclusions: Oncologic outcomes in a diverse cohort of patients with breast cancer who had a germline BRCA1/2 PV mutation and were treated with RT were similar to those of patients with no mutation, supporting the use of RT according to standard indications in patients with a germline BRCA1/2 PV mutation.
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http://dx.doi.org/10.1016/j.ijrobp.2021.09.033DOI Listing
October 2021

Anticoagulation Targeting Membrane-Bound Anionic Phospholipids Improved Outcomes of Traumatic Brain Injury in Mice.

Blood 2021 Oct 5. Epub 2021 Oct 5.

Division of Hematology, Department of Medicine, University of Washington, School of Medicine, Seattle, WA, United States.

Severe traumatic brain injury (TBI) often causes an acute systemic hypercoagulable state that rapidly develops into consumptive coagulopathy. We have recently demonstrated that TBI-induced coagulopathy (TBI-IC) is initiated and disseminated by brain-derived extracellular vesicles (BDEVs) and propagated by extracellular vesicles (EVs) from endothelial cells and platelets. Here, we present results from a study designed to test the hypothesis that anticoagulation targeting anionic phospholipid-expressing EVs prevents TBI-IC and improves the outcomes of mice subjected to severe TBI. We evaluated the effects of a fusion protein (ANV-6L15) for improving the outcomes of TBI. ANV-6L15 combines the phosphatidylserine (PS)-binding annexin V with a peptide anticoagulant modified to preferentially target extrinsic coagulation. We found that ANV-6L15 reduced intracranial hematoma by 70.2%, improved neurological function, and reduced death by 56.8% in mice subjected to fluid percussion injury at 1.9 atm. It protected the TBI mice by preventing vascular leakage, tissue edema, and the TBI-induced hypercoagulable state. We further showed that the extrinsic tenase complex was formed on the surfaces of circulating EVs, with the highest level found on BDEVs. Phospholipidomic analysis detected the highest levels of PS on BDEVs, as compared to EVs from endothelial cells and platelets (79.1, 15.2, and 3.5 nM/mg of protein, respectively). These findings demonstrate that TBI-IC results from a trauma-induced hypercoagulable state and may be treated by anticoagulation targeting on the anionic phospholipid-expressing membrane of EVs from the brain and other cells.
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http://dx.doi.org/10.1182/blood.2021011310DOI Listing
October 2021

Construction of hierarchical-porous metal-organic frameworks through esterification reaction for efficient catalysis.

Chem Commun (Camb) 2021 Oct 14;57(82):10795-10798. Epub 2021 Oct 14.

Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, China.

A solvent-assisted strategy was proposed by controlling the coordination equilibrium to fabricate hierarchical-porous metal-organic frameworks (HP-MOFs). The obtained HP-MOFs showed remarkable enhancement in catalytic efficiency in Lewis acid catalysis resulting from the joint efforts of the hierarchical pores and the exposed metal clusters.
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http://dx.doi.org/10.1039/d1cc03059kDOI Listing
October 2021

Breast Radiation Therapy-Related Treatment Outcomes in Patients With or Without Germline Mutations on Multigene Panel Testing.

Int J Radiat Oncol Biol Phys 2021 Sep 25. Epub 2021 Sep 25.

Departments of Radiation Oncology. Electronic address:

Purpose: Multigene panel testing has increased the detection of germline mutations in patients with breast cancer. The implications of using radiation therapy (RT) to treat patients with pathogenic variant (PV) mutations are not well understood and have been studied mostly in women with only BRCA1 or BRCA2 PVs. We analyzed oncologic outcomes and toxicity after adjuvant RT in a contemporary, diverse cohort of patients with breast cancer who underwent genetic panel testing.

Methods And Materials: We retrospectively reviewed the records of 286 women with clinical stage I-III breast cancer diagnosed from 1995 to 2017 who underwent surgery, breast or chest wall RT with or without regional nodal irradiation, multigene panel testing, and evaluation at a large cancer center's genetic screening program. We evaluated rates of overall survival, locoregional recurrence, disease-specific death, and radiation-related toxicities in 3 groups: BRCA1/2 PV carriers, non-BRCA1/2 PV carriers, and patients without PV mutations.

Results: PVs were detected in 25.2% of the cohort (12.6% BRCA1/2 and 12.6% non-BRCA1/2). The most commonly detected non-BRCA1/2 mutated genes were ATM, CHEK2, PALB2, CDH1, TP53, and PTEN. The median follow-up time for the entire cohort was 4.4 years (95% confidence interval, 3.8-4.9 years). No differences were found in overall survival, locoregional recurrence, or disease-specific death between groups (P > .1 for all). Acute and late toxicities were comparable across groups.

Conclusion: Oncologic and toxicity outcomes after RT in women with PV germline mutations detected by multigene pane testing are similar to those in patients without detectable mutations, supporting the use of adjuvant RT as a standard of care when indicated.
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http://dx.doi.org/10.1016/j.ijrobp.2021.09.026DOI Listing
September 2021

Imatinib protects against human beta-cell death via inhibition of mitochondrial respiration and activation of AMPK.

Clin Sci (Lond) 2021 10;135(19):2243-2263

Science for Life Laboratory, Department of Medical Cell Biology, Uppsala University, Box 571, SE-751 23 Uppsala, Sweden.

The protein tyrosine kinase inhibitor imatinib is used in the treatment of various malignancies but may also promote beneficial effects in the treatment of diabetes. The aim of the present investigation was to characterize the mechanisms by which imatinib protects insulin producing cells. Treatment of non-obese diabetic (NOD) mice with imatinib resulted in increased beta-cell AMP-activated kinase (AMPK) phosphorylation. Imatinib activated AMPK also in vitro, resulting in decreased ribosomal protein S6 phosphorylation and protection against islet amyloid polypeptide (IAPP)-aggregation, thioredoxin interacting protein (TXNIP) up-regulation and beta-cell death. 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR) mimicked and compound C counteracted the effect of imatinib on beta-cell survival. Imatinib-induced AMPK activation was preceded by reduced glucose/pyruvate-dependent respiration, increased glycolysis rates, and a lowered ATP/AMP ratio. Imatinib augmented the fractional oxidation of fatty acids/malate, possibly via a direct interaction with the beta-oxidation enzyme enoyl coenzyme A hydratase, short chain, 1, mitochondrial (ECHS1). In non-beta cells, imatinib reduced respiratory chain complex I and II-mediated respiration and acyl-CoA carboxylase (ACC) phosphorylation, suggesting that mitochondrial effects of imatinib are not beta-cell specific. In conclusion, tyrosine kinase inhibitors modestly inhibit mitochondrial respiration, leading to AMPK activation and TXNIP down-regulation, which in turn protects against beta-cell death.
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http://dx.doi.org/10.1042/CS20210604DOI Listing
October 2021

Effect of Camrelizumab vs Placebo Added to Chemotherapy on Survival and Progression-Free Survival in Patients With Advanced or Metastatic Esophageal Squamous Cell Carcinoma: The ESCORT-1st Randomized Clinical Trial.

JAMA 2021 09;326(10):916-925

Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.

Importance: Standard first-line therapy for advanced or metastatic esophageal carcinoma is chemotherapy, but the prognosis remains poor. Camrelizumab (an anti-programmed death receptor 1 [PD-1] antibody) showed antitumor activity in previously treated advanced or metastatic esophageal squamous cell carcinoma.

Objective: To evaluate the efficacy and adverse events of camrelizumab plus chemotherapy vs placebo plus chemotherapy as a first-line treatment in advanced or metastatic esophageal squamous cell carcinoma.

Design, Setting, And Participants: This randomized, double-blind, placebo-controlled, multicenter, phase 3 trial (ESCORT-1st study) enrolled patients from 60 hospitals in China between December 3, 2018, and May 12, 2020 (final follow-up, October 30, 2020). A total of 751 patients were screened and 596 eligible patients with untreated advanced or metastatic esophageal squamous cell carcinoma were randomized.

Interventions: Patients were randomized 1:1 to receive either camrelizumab 200 mg (n = 298) or placebo (n = 298), combined with up to 6 cycles of paclitaxel (175 mg/m2) and cisplatin (75 mg/m2). All treatments were given intravenously every 3 weeks.

Main Outcomes And Measures: Coprimary end points were overall survival (significance threshold, 1-sided P < .02) and progression-free survival (significance threshold, 1-sided P < .005).

Results: Of the 596 patients randomized (median age, 62 years [interquartile range, 56-67 years]; 523 men [87.8%]), 1 patient in the placebo-chemotherapy group did not receive planned treatment. A total of 490 patients (82.2%) had discontinued the study treatment. The median follow-up was 10.8 months. The overall survival for the camrelizumab-chemotherapy group was a median of 15.3 months (95% CI, 12.8-17.3; 135 deaths) vs a median of 12.0 months (95% CI, 11.0-13.3; 174 deaths) for the placebo-chemotherapy group (hazard ratio [HR] for death, 0.70 [95% CI, 0.56-0.88]; 1-sided P = .001). Progression-free survival for camrelizumab plus chemotherapy was a median of 6.9 months (95% CI, 5.8-7.4; 199 progression or deaths) vs 5.6 months (95% CI, 5.5-5.7; 229 progression or deaths) for the placebo-chemotherapy group (HR for progression or death, 0.56 [95% CI, 0.46-0.68]; 1-sided P < .001). Treatment-related adverse events of grade 3 or higher occurred in 189 patients (63.4%) in the camrelizumab-chemotherapy group and 201 (67.7%) in the placebo-chemotherapy group, including treatment-related deaths among 9 patients (3.0%) and 11 patients (3.7%), respectively.

Conclusions And Relevance: Among patients with advanced or metastatic esophageal squamous cell carcinoma, the addition of camrelizumab to chemotherapy, compared with placebo and chemotherapy, significantly improved overall survival and progression-free survival.

Trial Registration: ClinicalTrials.gov Identifier: NCT03691090.
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http://dx.doi.org/10.1001/jama.2021.12836DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8441593PMC
September 2021

Harpagide alleviate neuronal apoptosis and blood-brain barrier leakage by inhibiting TLR4/MyD88/NF-κB signaling pathway in Angiotensin II-induced microglial activation in vitro.

Chem Biol Interact 2021 Oct 10;348:109653. Epub 2021 Sep 10.

Department of Neurology, Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu Province, 210001, China. Electronic address:

Angiotensin II, the effector peptide of the renin-angiotensin system, is not only a pivotal peptide implicated in the regulation of blood pressure but also a key mediator of the inflammatory processes that play an important role in the pathology of hypertension-related cSVD. Harpagide is the major bioactive constituent of Scrophulariae Radix widely used in traditional Chinese medicine for numerous diseases including hypertension. The present study aimed to investigate the effect of harpagide on Ang II-induced neuroinflammation and the potential mechanism. Pretreated with harpagide or resatorvid (the TLR4 pathway inhibitor), BV2 cells were treated with Ang II or LPS (the TLR4 activator). NO, pro-inflammatory cytokines, the proteins on TLR4/MyD88/NF-κB signaling pathway and the expression of CD86, CD206, TREM2 in BV2 cells were detected respectively. Subsequently, the effects of harpagide on neurotoxicity and BBB destruction triggered by Ang II-induced neuroinflammation were investigated in the co-cultures of BV2 microglia/HT22 hippocampal neurons, BV2 microglia/bEnd.3 endotheliocyte and BV2 microglia/BBB monolayer model. We found that Ang II converted microglia into M1 state and resulted in neuroinflammation through activating TLR4/MyD88/NF-κB signaling pathway. It also triggered the imbalance of TLR4/TREM2 in microglia. Ang II-mediated inflammation microglia further led to neuronal apoptosis and BBB damage. Harpagide showed the effect of alleviating Ang II-mediated neuroinflammation as well as the resulting neurotoxicity and BBB destruction through inhibiting the TLR4/MyD88/NF-κB pathway. The anti-inflammatory and neuroprotective effect of harpagide suggested that it might be a potential therapeutic strategy in hypertensive cSVD.
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http://dx.doi.org/10.1016/j.cbi.2021.109653DOI Listing
October 2021

Storage temperature determines platelet GPVI levels and function in mice and humans.

Blood Adv 2021 10;5(19):3839-3849

Bloodworks Northwest Research Institute, Seattle, WA; and.

Platelets are currently stored at room temperature before transfusion to maximize circulation time. This approach has numerous downsides, including limited storage duration, bacterial growth risk, and increased costs. Cold storage could alleviate these problems. However, the functional consequences of cold exposure for platelets are poorly understood. In the present study, we compared the function of cold-stored platelets (CSP) with that of room temperature-stored platelets (RSP) in vitro, in vivo, and posttransfusion. CSP formed larger aggregates under in vitro shear while generating similar contractile forces compared with RSP. We found significantly reduced glycoprotein VI (GPVI) levels after cold exposure of 5 to 7 days. After transfusion into humans, CSP were mostly equivalent to RSP; however, their rate of aggregation in response to the GPVI agonist collagen was significantly lower. In a mouse model of platelet transfusion, we found a significantly lower response rate to the GPVI-dependent agonist convulxin and significantly lower GPVI levels on the surface of transfused platelets after cold storage. In summary, our data support an immediate but short-lived benefit of cold storage and highlight the need for thorough investigations of CSP. This trial was registered at www.clinicaltrials.gov as #NCT03787927.
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http://dx.doi.org/10.1182/bloodadvances.2021004692DOI Listing
October 2021

INHBA is a novel mediator regulating cellular senescence and immune evasion in colorectal cancer.

J Cancer 2021 13;12(19):5938-5949. Epub 2021 Aug 13.

Center of Gastrointestinal disease, The Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China.

Colorectal cancer (CRC) is one of the most mortal cancers in the world. Multiple factors and bio-processes are associated with in tumorigenesis and metastasis of CRC, including cellular senescence and immune evasion. This study aims to identify prognostic and immune-meditating effects of INHBA in CRC. Microarray datasets were downloaded from the Gene Expression Omnibus (GEO) database to screen the differentially expressed genes (DEGs) in senescent cells and CRC tissues from the Cancer Genome Atlas (TCGA). Key factor was settled from the alternative DEGs set. Enrichment analyses and functional networks prediction were determined from online databases. Correlation analyses were performed to reveal the association among key factor, immune infiltration, T cell biomarkers and immune checkpoints. Moreover, expressions of key factors and immune checkpoints of tissue and blood samples from CRC patients as well as human CRC cell lines were measured. Results showed that Inhibin beta A (INHBA) was sorted out as a senescence-related factor and a prognostic predictor in CRC. What's more, INHBA was found highly co-expressed with T-cell biomarkers and immune checkpoints. In conclusion, INHBA was considered as a senescence-related regulator and a prognostic predictor in CRC, which also mediating immune evasion.
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http://dx.doi.org/10.7150/jca.61556DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8408109PMC
August 2021

Genome-wide identification, gene cloning, subcellular location and expression analysis of SPL gene family in P. granatum L.

BMC Plant Biol 2021 Aug 28;21(1):400. Epub 2021 Aug 28.

Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, China.

Backgrounds: Pomegranate is an excellent tree species with nutritional, medicinal, ornamental and ecological values. Studies have confirmed that SPL factors play an important role in floral transition and flower development.

Results: Used bioinformatics methods, 15 SPL (SQUAMOSA promoter-binding protein-like) genes were identified and analyzed from the 'Taishanhong' pomegranate (P. granatum L.) genome. Phylogenetic analysis showed that PgSPLs were divided into six subfamilies (G1 ~ G6). PgSPL promoter sequences contained multiple cis-acting elements associated with abiotic stress or hormonal response. Based on the transcriptome data, expression profiles of different tissues and different developmental stages showed that PgSPL genes had distinct temporal and spatial expression characteristics. The expression analysis of miR156 in small RNA sequencing results showed that miR156 negatively regulated the expression of target genes. qRT-PCR analysis showed that the expression levels of PgSPL2, PgSPL3, PgSPL6, PgSPL11 and PgSPL14 in leaves were significantly higher than those in buds and stems (p < 0.05). The expression levels of PgSPL5, PgSPL12 and PgSPL13 in flower buds were significantly higher than that in leaves and stems (p < 0.05). The full-length of coding sequence of PgSPL5 and PgSPL13 were obtained by homologous cloning technology. The full length of PgSPL5 is 1020 bp, and PgSPL13 is 489 bp, which encodes 339 and 162 amino acids, respectively. Further investigation revealed that PgSPL5 and PgSPL13 proteins were located in the nucleus. Exogenous plant growth regulator induction experiments showed that PgSPL5 was up-regulated in leaves and stems. PgSPL13 was up-regulated in leaves and down-regulated in stems. When sprayed with 6-BA, IBA and PP333 respectively, PgSPL5 and PgSPL13 were up-regulated most significantly at P2 (bud vertical diameter was 5.1 ~ 12.0 mm) stage of bisexual and functional male flowers.

Conclusions: Our findings suggested that PgSPL2, PgSPL3, PgSPL6, PgSPL11 and PgSPL14 played roles in leaves development of pomegranate. PgSPL5, PgSPL12 and PgSPL13 played roles in pomegranate flower development. PgSPL5 and PgSPL13 were involved in the response process of different plant hormone signal transduction in pomegranate development. This study provided a robust basis for further functional analyses of SPL genes in pomegranate.
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http://dx.doi.org/10.1186/s12870-021-03171-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8399725PMC
August 2021

A Machine Learning Study on the Thermostability Prediction of (R)--Selective Amine Transaminase from Aspergillus terreus.

Biomed Res Int 2021 16;2021:2593748. Epub 2021 Aug 16.

School of Science, School of Big Data, Zhejiang University of Science and Technology, Hangzhou 310008, China.

Artificial intelligence technologies such as machine learning have been applied to protein engineering, with unique advantages in protein structure, function prediction, catalytic activity, and other issues in recent years. Screening better mutants is still a bottleneck in protein engineering. In this paper, a new sequence-activity relationship method was analyzed for its application in improving the thermal stability of Aspergillus terreus (R)--selective amine transaminase. The experimental data from 6 single-point mutated enzymes were used as a learning dataset to build models and predict the thermostability of 2 mutants. Based on digital signal processing (DSP), this method digitized the amino acid sequence of proteins by fast Fourier transform (FFT) and then established the best model applying partial least squares regression (PLSR) to screen out all possible mutants, especially those with high performance. In protein engineering, the innovative sequence activity relationship (ISAR) method can make a reasonable prediction using limited experimental data and significantly reduce the experimental cost. The half-life ( ) of (R)--transaminase was fitted with the amino acid sequence by the ISAR algorithm, resulting in an of 0.8929 and a cvRMSE of 4.89. At the same time, the mutants with higher than the existing ones were predicted, laying the groundwork for better (R)--transaminase in the later stage. The ISAR algorithm is expected to provide a new technique for protein evolution and screening.
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http://dx.doi.org/10.1155/2021/2593748DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8384528PMC
September 2021

Improved production of 2'-fucosyllactose in engineered Saccharomyces cerevisiae expressing a putative α-1, 2-fucosyltransferase from Bacillus cereus.

Microb Cell Fact 2021 Aug 23;20(1):165. Epub 2021 Aug 23.

State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No.72 Binhai Road, Qingdao, 266237, People's Republic of China.

Background: 2'-fucosyllactose (2'-FL) is one of the most abundant oligosaccharides in human milk. It constitutes an authorized functional additive to improve infant nutrition and health in manufactured infant formulations. As a result, a cost-effective method for mass production of 2'-FL is highly desirable.

Results: A microbial cell factory for 2'-FL production was constructed in Saccharomyces cerevisiae by expressing a putative α-1, 2-fucosyltransferase from Bacillus cereus (FutBc) and enhancing the de novo GDP-L-fucose biosynthesis. When enabled lactose uptake, this system produced 2.54 g/L of 2'-FL with a batch flask cultivation using galactose as inducer and carbon source, representing a 1.8-fold increase compared with the commonly used α-1, 2-fucosyltransferase from Helicobacter pylori (FutC). The production of 2'-FL was further increased to 3.45 g/L by fortifying GDP-mannose synthesis. Further deleting gal80 enabled the engineered strain to produce 26.63 g/L of 2'-FL with a yield of 0.85 mol/mol from lactose with sucrose as a carbon source in a fed-batch fermentation.

Conclusion: FutBc combined with the other reported engineering strategies holds great potential for developing commercial scale processes for economic 2'-FL production using a food-grade microbial cell factory.
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http://dx.doi.org/10.1186/s12934-021-01657-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8381501PMC
August 2021

A novel LC-MS/MS method for complete composition analysis of polysaccharides by aldononitrile acetate and multiple reaction monitoring.

Carbohydr Polym 2021 Nov 24;272:118478. Epub 2021 Jul 24.

Key Laboratory of Chinese Materia Medica (Heilongjiang University of Chinese Medicine), Ministry of Education, 24 Heping Road, Harbin 150040, PR China. Electronic address:

Carbohydrate analysis has always been a challenging task due to the occurrence of high polarity and multiple isomers. Aldoses are commonly analyzed by gas liquid chromatography (GLC) following aldononitrile acetate derivatization (AND). However, the GLC technique cannot be applied for the simultaneous determination of aldoses, ketoses, and uronic acids. In this study, a new method based on the combination of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and AND is developed for the complete characterization of monosaccharide composition (i.e., aldoses, ketoses, alditols, amino sugars, and uronic acids) in plant-derived polysaccharides. In addition to discussing the possible byproducts, the study optimizes the multiple reaction monitoring (MRM) parameters and LC conditions. The final separation of 17 carbohydrates is performed on a BEH Shield RP18 column (150 mm × 2.1 mm, 1.7 μm) within 25 min, without using any buffer salt. Notably, the complex polysaccharides extracted from Ligusticum chuanxiong, Platycodon grandiflorum, Cyathula officinalis Kuan, Juglans mandshurica Maxim, and Aralia elata (Miq.). Seem bud can be successfully characterized using the developed method. Overall, the results demonstrated that the newly established LC-MS/MS MRM method is more effective and powerful than the GLC-based methods reported previously, and it is more suitable for the analysis of highly complex natural polysaccharides, including complex pectins, fructosans, and glycoproteins.
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http://dx.doi.org/10.1016/j.carbpol.2021.118478DOI Listing
November 2021

New mechanistic insights into the effect of cations on membrane fouling caused by anionic polyacrylamide.

J Colloid Interface Sci 2022 Jan 2;606(Pt 1):10-21. Epub 2021 Aug 2.

School of Environmental and Ecology, Chongqing University, Chongqing 400044, China.

Hypothesis: Understanding the effect of cations on membrane fouling is crucial for the widespread application of the membrane technology. However, contradictory results have been reported based on different studies. Moreover, although the effect of the ionic strength has been studied extensively, limited information is available on the effect of the ion type on membrane fouling.

Experiments: The physicochemical properties of the membrane and anionic polyacrylamide (APAM) were evaluated to calculate the APAM-membrane and APAM-APAM interfacial interaction energies under different conditions. Moreover, a series of microfiltration (MF) experiments was conducted to investigate the effects of the ionic conditions on the flux decline, pore blockage and cake layer resistances, and the flux recovery rate of APAM during the MF process.

Findings: As the ionic strength increased, the rate of decrease in the normalized flux increased, the total and cake layer resistances increased significantly, the pore blockage resistance was affected slightly, and the recovery rates of the water flux after physical and chemical cleaning decreased gradually, which could be clearly explained using the Derjaguin-Landau-Verwey-Overbeek theory. Furthermore, compared with Na, Ca could effectively mitigate the membrane fouling at an identical ionic strength, which is attributed to the hydration forces of APAM-membrane and APAM-APAM.
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http://dx.doi.org/10.1016/j.jcis.2021.07.148DOI Listing
January 2022

The Encounter of Biomolecules in Metal-Organic Framework Micro/Nano Reactors.

ACS Appl Mater Interfaces 2021 Aug 9. Epub 2021 Aug 9.

Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, P.R. China.

In nature, biochemical reactions often take place in confined spaces, as typically exemplified by cells. As numerous cellular reactors can be integrated to maintain the living system, researchers have made constant efforts to construct cell-like structures for achieving similar transformations in vitro. Micro/nano reactors engineered by polymers and colloids are becoming popular and being applied in many fields, especially there has been an increasing trend toward constructing metal-organic framework (MOF) micro/nano reactors with the thriving of MOF nanotechnologies. Because of the uniform pores of MOFs, the transmission of substances can be regulated more accurately. Along with properties of large specific surface area, functional diversity and precise control of the particle size, MOFs are also ideal platforms for building distinct microenvironments for biological substances. Compared with traditional polymersomes and colloidosomes, the unique characteristics of MOFs render them potent micro/nano reactor shell materials, mimicking cells for applications in enzymatic catalysis, sensing, nanotherapy, vaccine, biodegradation, etc. This review highlights recent signs of progress on the design of MOF micro/nano reactors and their applications in biology, discusses the existing problems, and prospects their promising properties for smarter multifunctional applications.
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http://dx.doi.org/10.1021/acsami.1c09660DOI Listing
August 2021

Prediction Descriptor for Catalytic Activity of Platinum Nanoparticles/Metal-Organic Framework Composites.

ACS Appl Mater Interfaces 2021 Aug 7;13(32):38325-38332. Epub 2021 Aug 7.

Key Laboratory of Flexible Electronics (KLOFE), Institute of Advanced Materials (IAM), Nanjing Tech University, Nanjing 211816, China.

Supported metal nanoparticles (MNPs) have exhibited superior catalytic performance in various heterogeneous catalysis applications, which is usually influenced or even determined by the physicochemical properties of their porous supports. It is well acknowledged that understanding the regulation mechanism of supports is an important prerequisite to predict the catalytic performance of supported MNPs as well as the development of advanced catalysts. Here, we demonstrated that different transition-metal clusters (from Group IIIB to Group IIB) within metal-organic frameworks (MOFs) could accurately regulate the surface electronic status of supported platinum nanoparticles (Pt NPs), and the Pt/MOF composites showed a periodic activity trend in hydrogenation of 1-hexene. A strong correlation was found between the catalytic activity of Pt/MOF composites and the number of electrons in their outmost d orbitals of the transition-metal species, suggesting that the latter could play the role of prediction descriptor. Furthermore, this descriptor can be extended to predict the hydrogenation activity of more Pt/MOF composites and provide an important guiding principle for the design of supported MNPs catalysts.
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http://dx.doi.org/10.1021/acsami.1c10140DOI Listing
August 2021

Enhancing the flow field in parallel spiral-flow column photobioreactor to improve CO fixation with Spirulina sp.

Sci Total Environ 2021 Dec 30;799:149314. Epub 2021 Jul 30.

College of Energy, Soochow University, Suzhou 215006, China. Electronic address:

A parallel spiral-flow column photobioreactor (PSCP) composed of eight spiral-flow columns, and two pipe headers was designed for scale-up cultivation of microalgae to capture CO. To solve the disturbance of spiral flow fields among parallel columns, computational fluid dynamics (CFD) simulation was used to optimize the main structural parameters, such as the number and the height of microalgae solution outlet (MSO), to improve flow field structure and enhance the cells' light/dark cycle. The horizontal velocity in the direction of optical path and the turbulent kinetic energy (TKE) reached the peak values of 0.214 m/s and 5.28 m/s when MSO number was four and MSO height was 1.05 m. Meanwhile, the disturbance of the spiral flow field among parallel columns are minimum, and microalgae light/dark cycle frequency was 33.3% higher than that of conventional bubble column photobioreactor. Therefore, the biomass yield and CO fixation rate of microalgae increased by 81.5% and 100.5%, respectively.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149314DOI Listing
December 2021
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