Publications by authors named "Yanping Liu"

315 Publications

circYap inhibits oral squamous cell carcinoma by arresting cell cycle.

Acta Odontol Scand 2021 Jul 19:1-8. Epub 2021 Jul 19.

College of Integrative Medicine, Hebei University of Chinese Medicine, Shijiazhuang, China.

Objective: Circular RNAs (circRNAs) involve in the development and progression of tumour. The mechanism of circRNAs in oral squamous cell carcinoma (OSCC) has remained unclear. This study aimed to investigate the role of circular Yes-associated protein (circYap) in OSCC.

Methods: Quantification reverse transcription-polymerase chain reaction (qRT-PCR) was applied to measure circYap expression in patients with OSCC tissues and cells. Flow cytometry was performed to evaluate cell cycle. circYap interaction with CDK4 was detected by RNA immunoprecipitation (RIP) and RNA pull-down. The interaction of Cyclin D1 and CDK4 was determined using co-immunoprecipitation (co-IP).

Results: We showed that circYap expression was downregulated in OSCC tissues. Using small interfering circular (Si-circYap) and overexpression plasmid, we found that circYap overexpression inhibited proliferation and arrested cell cycle in OSCC cells, while, circYap knockdown yielded the opposite result. Cyclin D1/CDK4 complexes and nuclear translocation is essential for cell cycle progression. We found that CDK4 interacted with circYap was increased when circYap overexpression, meanwhile, Cyclin D1/CDK4 complexes and of nuclear distribution were decreased.

Conclusions: Our findings suggest that circYap impedes progression of OSCC. Overexpression of circYap suppresses proliferation and cell cycle through binding to CDK4 to block formation and nuclear translocation of Cyclin D1/CDK4 complexes. Thus, circYap may serves as a valuable therapeutic target for OSCC.
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http://dx.doi.org/10.1080/00016357.2021.1946136DOI Listing
July 2021

Photocatalytic Oxidation of SO by TiO: Aerosol Formation and the Key Role of Gaseous Reactive Oxygen Species.

Environ Sci Technol 2021 Jul 7;55(14):9784-9793. Epub 2021 Jul 7.

Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.

Photocatalytic materials are proved to effectively eliminate gaseous pollutants and are widely used in the environment. However, as one of the rare experiments focusing on their influence on secondary aerosol formation generated in the gas phase (SA), our study demonstrated the high-yield SA formation in the photocatalysis process. In this study, the photodegradation of SO by TiO under various relative humidity (RH) conditions was deeply explored with multiple methods. Unexpectedly, HSO aerosols (SA) in yields of 10.10-32.64% were observed under the studied RH conditions for the first time. Gaseous OH and HO generated from the oxidation of HO and reduction of O by TiO were directly detected in the photocatalysis process, and they were identified as the determining factor for SA formation. The formation of SA was also influenced by RH, the heterogeneous reaction of SO, and the uptake of HSO. The role of the released gaseous OH and HO on atmospheric chemistry was proved to be unignorable by adopting the obtained parameters into the real environment. These findings provided direct experimental evidence of secondary pollution in the photocatalysis process and are of great significance to the field of atmospheric environment and photocatalytic materials.
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http://dx.doi.org/10.1021/acs.est.1c01608DOI Listing
July 2021

Trade-in Strategy and Competition between Two Independent Remanufacturers.

Int J Environ Res Public Health 2021 Jun 23;18(13). Epub 2021 Jun 23.

Department of Management Science and Engineering, Business School, Nankai University, Tianjin 300071, China.

Trade-in strategy is a common mode of promotion for firms taking part in the circular economy because it encourages consumers to buy remanufactured products, via a "trade-old-for-remanufactured" framework. This paper studies trade-in strategy by developing game models for a closed-loop supply chain with one manufacturer and two independent remanufacturers. The former is responsible for producing and selling new products and the latter two compete with each other for the collection of used products and the sales of remanufactured products. Unlike the extant literature, this paper focuses on the competition between two independent remanufacturers (IRs) and studies on how holder segment (whether or not to own used products) and competition affects the trade-in strategy. It finds that the proportion of holders on the remanufactured product prices of the IR1 and IR2 have a negative correlation. Conversely, the impact of the proportion of holders on the IR1's and IR2's demands (and on their profits) is the opposite. The trade-in strategy generates more benefits for the IR1 only when the proportion of holders is sufficiently high. In addition, when consumers experience a greater difference in durability between remanufactured products and original new products, trade-in strategy is more welcomed by consumers, which in turn, generates more benefits for the IR1.
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http://dx.doi.org/10.3390/ijerph18136745DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8267848PMC
June 2021

The transcriptional co-regulator LDB1 is required for brown adipose function.

Mol Metab 2021 Jun 29:101284. Epub 2021 Jun 29.

Comprehensive Diabetes Center and Department of Medicine, USA; Division of Endocrinology, Diabetes and Metabolism, University of Alabama at Birmingham, Birmingham, AL, USA. Electronic address:

Objective: Brown adipose tissue (BAT) is critical for thermogenesis and glucose/lipid homeostasis. Exploiting the energy uncoupling capacity of BAT may reveal targets for obesity therapies. This exploitation requires a greater understanding of the transcriptional mechanisms underlying BAT function. One potential regulator of BAT is the transcriptional co-regulator LIM domain-binding protein 1 (LDB1), which acts as a dimerized scaffold, allowing for the assembly of transcriptional complexes. Utilizing a global LDB1 heterozygous mouse model, we recently reported that LDB1 might have novel roles in regulating BAT function. However, direct evidence for the LDB1 regulation of BAT thermogenesis and substrate utilization has not been elucidated. We hypothesize that brown adipocyte-expressed LDB1 is required for BAT function.

Methods: LDB1-deficient primary cells and brown adipocyte cell lines were assessed via qRT-PCR and western blotting for altered mRNA and protein levels to define the brown adipose-specific roles. We conducted chromatin immunoprecipitation with primary BAT tissue and immortalized cell lines. Potential transcriptional partners of LDB1 were revealed by conducting LIM factor surveys via qRT-PCR in mouse and human brown adipocytes. We developed a Ucp1-Cre-driven LDB1-deficiency mouse model, termed Ldb1, to test LDB1 function in vivo. Glucose tolerance and uptake were assessed at thermoneutrality via intraperitoneal glucose challenge and glucose tracer studies. Insulin tolerance was measured at thermoneutrality and after stimulation with cold or the administration of the β3-adrenergic receptor (β3-AR) agonist CL316,243. Additionally, we analyzed plasma insulin via ELISA and insulin signaling via western blotting. Lipid metabolism was evaluated via BAT weight, histology, lipid droplet morphometry, and the examination of lipid-associated mRNA. Finally, energy expenditure and cold tolerance were evaluated via indirect calorimetry and cold challenges.

Results: Reducing Ldb1 in vitro and in vivo resulted in altered BAT-selective mRNA, including Ucp1, Elovl3, and Dio2. In addition, there was reduced Ucp1 induction in vitro. Impacts on gene expression may be due, in part, to LDB1 occupying Ucp1 upstream regulatory domains. We also identified BAT-expressed LIM-domain factors Lmo2, Lmo4, and Lhx8, which may partner with LDB1 to mediate activity in brown adipocytes. Additionally, we observed LDB1 enrichment in human brown adipose. In vivo analysis revealed LDB1 is required for whole-body glucose and insulin tolerance, in part through reduced glucose uptake into BAT. In Ldb1 tissue, we found significant alterations in insulin-signaling effectors. An assessment of brown adipocyte morphology and lipid droplet size revealed larger and more unilocular brown adipocytes in Ldb1 mice, particularly after a cold challenge. Alterations in lipid handling were further supported by reductions in mRNA associated with fatty acid oxidation and mitochondrial respiration. Finally, LDB1 is required for energy expenditure and cold tolerance in both male and female mice.

Conclusions: Our findings support LDB1 as a regulator of BAT function. Furthermore, given LDB1 enrichment in human brown adipose, this co-regulator may have conserved roles in human BAT.
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http://dx.doi.org/10.1016/j.molmet.2021.101284DOI Listing
June 2021

ubiquitination and degradation of bacteria-purified human histone H2B by the nucleoli fractions.

STAR Protoc 2021 Jun 11;2(2):100601. Epub 2021 Jun 11.

Laboratory of Molecular and Cellular Biology, School of Basic Medical Sciences, Henan University School of Medicine, Kaifeng, Henan 475004, PR China.

Histones are the main components of chromatin, and the protein levels of histones significantly affect chromatin assembly. Here, we describe detailed protocols for histone H2B purification from bacteria and for the separation of nucleolar fractions and cytoplasmic and nucleoplasmic fractions. Finally, the in vitro ubiquitination and degradation of H2B by distinct cellular fractions are described. For complete details on the use and execution of this protocol, please refer to Liu et al. (2021).
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http://dx.doi.org/10.1016/j.xpro.2021.100601DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8209693PMC
June 2021

Biological gel-based microchamber array for tumor cell proliferation and migration studies in well-controlled biochemical gradients.

Lab Chip 2021 Jun 23. Epub 2021 Jun 23.

Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing 401331, China.

Breast cancer metastasis is a complex process controlled by multiple factors, including various cell-cell interactions, cell-environment coupling, and oxygen, nutrient and drug gradients that are intimately related to the heterogeneous breast tissue structure. In this study, we constructed a high-throughput in vitro biochip system containing an array of 642 microchambers arranged in a checkerboard configuration, with each chamber embedded in a composite extracellular matrix (ECM) composed of engineered collagen and Matrigel to mimic local heterogeneous environment in vivo. In addition, a controllable complex tetragonal chemical concentration profile can be achieved by imposing chemical compounds at the four boundaries of the chip, leading to distinct local nutrient and/or drug gradients in the individual microchambers. Here, the microchamber array with composite ECM (MACECM) device aims to simulate multiple tumor cell niches composed of both breast epithelial cells (MCF-10A-GFP) and metastatic breast cancer cells (MDA-MB-231-RFP), which enables systematic studies of cell responses to a variety of biochemical conditions. The results obtained from the MACECM studies indicate that discoidin domain receptor 1 (DDR1) inhibitor 7rh and matrix metalloproteinase inhibitor batimastat, in association with epidermal growth factor (EGF) had no significant effects on the growth of MCF-10A-GFP cells, but had significant effects on DDR1 expression and the related migratory behavior of MDA-MB-231-RFP cells. The MACECM design not only enables the construction of a more realistic in vitro model for investigating cancer cell migration mechanisms but also has considerable potential for further development as a platform for next-generation high-throughput and therapeutic screening (e.g., anti-cancer drug evaluation) and personalized medicine.
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http://dx.doi.org/10.1039/d0lc00951bDOI Listing
June 2021

Oncologic and survival outcomes in elderly patients with locally advanced rectal cancer receiving neoadjuvant chemoradiotherapy and total mesorectal excision.

Jpn J Clin Oncol 2021 Jun 21. Epub 2021 Jun 21.

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

Background: The efficacy of the addition of neoadjuvant chemotherapy to neoadjuvant chemoradiotherapy and total mesorectal excision for locally advanced rectal cancer in elderly patients has not been established.

Methods: A total of 3096 locally advanced rectal cancer patients who received neoadjuvant chemotherapy, along with neoadjuvant chemoradiotherapy and total mesorectal excision, with or without adjuvant chemotherapy, between January 2010 and December 2018, were studied retrospectively. Patients were divided into elderly (>75 years) and younger (≤75 years) groups, and propensity score matching was used to balance a potentially confounding clinical bias. Overall survival, cancer-specific survival, disease-free survival, distant metastasis-free survival and local recurrence-free survival rates for the two groups were compared. Hazard ratios (HR) with 95% confidence intervals (CI) for different clinicopathological variables were calculated to determine predictors of 3-year overall survival.

Results: Mean follow-up was 39.0 (range, 5-140) months. The overall 3-year overall survival, cancer-specific survival, disease-free survival, distant metastasis-free survival and locoregional relapse-free survival rates were 86.1, 87.6, 80.0, 82.4 and 95.4%, respectively. Only 3-year overall survival rates differed significantly between the elderly (77.2%) and younger (88.9%) groups (P = 0.01). Cancer-specific survival, disease-free survival, distant metastasis-free survival and locoregional relapse-free survival rates did not differ significantly between the two groups. Significant negative independent prognostic factors for 3-year overall survival were age >75 years (HR = 2.016, 95% CI 1.157-23.511, P = 0.01) and high pathologic TNM stage (yp stage III, P < 0.001).

Conclusion: For elderly locally advanced rectal cancer patients who have good health and performance status, the addition of neoadjuvant chemotherapy to neoadjuvant chemoradiotherapy and total mesorectal excision can result in disease-related survival rates and oncological outcomes similar to those experienced by younger patients. The decision to use this treatment approach in elderly patients should not be based solely on chronological age.
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http://dx.doi.org/10.1093/jjco/hyab095DOI Listing
June 2021

The effect of dexmedetomidine on biological behavior of osteosarcoma cells through miR-1307 expression.

Am J Transl Res 2021 15;13(5):4876-4883. Epub 2021 May 15.

Department of Spinal Column Surgery, Zhoushan Guhechuan Hospital Zhoushan 316000, Zhejiang, China.

Objectives: This study analyzed the effect of dexmedetomidine (DEX) on biological behavior of osteosarcoma cells through expression of miR-1307.

Methods: We performed routine culture of human osteosarcoma cells MG-63 and randomly divided into control group, low-dose DEX group (25 ng/ml), medium-dose DEX group (50 ng/ml) and high-dose DEX group (100 ng/ml). Subsequently, we detected the cell proliferation (by CCK8 method), cell apoptosis (flow cytometry), mir-1307 expression (qRT-PCR), cell invasion (Transwell), and cell migration (scratch test) respectively.

Results: The growth rate of osteosarcoma cells MG-63 slowed down with the increase of DEX concentration. Compared with the control group, the cellular absorbance in groups with different DEX dose decreased remarkably after 72 hours of culture (). The proportion of apoptotic cells increased as well with the uplifting of DEX concentration, and the apoptotic rate in medium and high dosed DEX groups were remarkably higher than which in control group (). Compared with the control group, the invasive ability of MG-63 cells after DEX treatment decreased significantly, and with the increase of DEX concentration, the number of invasive cells declined more obviously (). Compared with the control group, the mobility rate of MG-63 cells after DEX treatment decreased significantly, and with the increase of DEX concentration, the cell mobility rate decreased more remarkably (). In addition, the relative expression of miR-1307 in MG-63 cells after DEX treatment decreased significantly comparing to the control group, and the decline was more noteworthy with the increase of DEX concentration ().

Conclusion: DEX can effectively inhibit the proliferation, invasion, metastasis, and apoptosis of osteosarcoma cells in a dose-dependent manner, and its efficacy may be related to its regulation of miR-1307 expression.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8205663PMC
May 2021

FLIM as a Promising Tool for Cancer Diagnosis and Treatment Monitoring.

Nanomicro Lett 2021 Jun 3;13(1):133. Epub 2021 Jun 3.

Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya Medical School, Central South University, Changsha, 410013, Hunan, People's Republic of China.

Fluorescence lifetime imaging microscopy (FLIM) has been rapidly developed over the past 30 years and widely applied in biomedical engineering. Recent progress in fluorophore-dyed probe design has widened the application prospects of fluorescence. Because fluorescence lifetime is sensitive to microenvironments and molecule alterations, FLIM is promising for the detection of pathological conditions. Current cancer-related FLIM applications can be divided into three main categories: (i) FLIM with autofluorescence molecules in or out of a cell, especially with reduced form of nicotinamide adenine dinucleotide, and flavin adenine dinucleotide for cellular metabolism research; (ii) FLIM with Förster resonance energy transfer for monitoring protein interactions; and (iii) FLIM with fluorophore-dyed probes for specific aberration detection. Advancements in nanomaterial production and efficient calculation systems, as well as novel cancer biomarker discoveries, have promoted FLIM optimization, offering more opportunities for medical research and applications to cancer diagnosis and treatment monitoring. This review summarizes cutting-edge researches from 2015 to 2020 on cancer-related FLIM applications and the potential of FLIM for future cancer diagnosis methods and anti-cancer therapy development. We also highlight current challenges and provide perspectives for further investigation.
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http://dx.doi.org/10.1007/s40820-021-00653-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175610PMC
June 2021

The Impact of Preconceptional Hysterosalpingography with Oil-based Contrast on Maternal and Neonatal Iodine Status.

Reprod Sci 2021 Jun 2. Epub 2021 Jun 2.

Beijing Key Laboratory of the Innovative Development of Functional Staple and the Nutritional Intervention for Chronic Disease, Department of Clinical Nutrition, Peking Union Medical College Hospital (PUMCH), No. 1 in Shuaifuyuan Street, Dongdan Street, Dongcheng District, Beijing, 100730, China.

The objective of this study is to investigate the impact of preconceptional exposure to oil-based iodinated contrast in the hysterosalpingography (HSG) on pregnant women and their offspring's iodine status, thyroid function, and the outcomes of pregnancy. A cross-sectional evaluation of iodine status was performed on pregnant women with the preconceptional experience of ethiodized-oil HSG. For those found to have iodine excess (with serum iodine concentration (SIC) > 92 μg/L), a prospective follow-up was conducted until termination of the pregnancy or 1 week postpartum. Among 70 of 425 pregnant women with preconceptional ethiodized-oil HSG, iodine excess was initially confirmed in 38 (54.3%), with an elevated SIC (294.00 μg/L [142.00, 123.20]) and urinary iodine-to-creatinine ratio (UI/Cr) (830.00 μg/g Cr [437.50, 255.30]), both higher than the normative data (P = 0.000, P = 0.000). Subsequent follow-up in pregnancy showed a downward trend in both SIC and UI/Cr. Thirty-four women delivered healthy neonates at full term, though the other 4 cases of premature birth, abnormal fetal karyotype, spontaneous abortion, and neonatal cardiac defect were reported. After delivery, the iodine concentration in maternal breast milk and neonatal urine was 584.50 μg/L [328.50, 1507.50] and 424.00 μg/L [277.00, 657.50], respectively, both higher than normative data (P = 0.001, P = 0.015). For thyroid evaluation, 25 cases (65.79%) of clinical or subclinical hypothyroidism and 2 cases (5.26%) of thyrotoxicosis were confirmed in women with iodine excess. Neither goiter nor thyroid dysfunction was detected in any offspring. Preconceptional exposure to oil-based contrast in HSG might exert a far-reaching impact on maternal and offspring iodine status, and tend to result in increased risk of maternal thyroid dysfunction.
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http://dx.doi.org/10.1007/s43032-021-00640-0DOI Listing
June 2021

Elder abuse in life stories: a qualitative study on rural Chinese older people.

J Elder Abuse Negl 2021 Jun 1;33(3):206-220. Epub 2021 Jun 1.

Department of Psychology, Honghe University, Mengzi City, China.

Holding beliefs such as elder respect seems to make Chinese older adults vulnerable to feel abused. This study investigated how Chinese older people in the countryside perceive abuse and make sense of their abusive experiences while telling their life stories. Following a narrative approach, we conducted semi-structured interviews with 17 older persons living in a rural village, Yunnan province, China, collected their life stories, and paid special attention to their telling of abuses. Thematic analysis of the data suggests that elder abuse for the participants is a betrayal of trust that is established within Chinese cultural values. Four themes were identified in explaining the participants' experiences of abuse: disrespect, dependency and the down-valued self, disconnection and rejection, and social comparisons in the construction of abuse. We discuss implications for future research and practices in stopping elder abuse.
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http://dx.doi.org/10.1080/08946566.2021.1934768DOI Listing
June 2021

Nuclear factor erythroid 2-related factor 2 potentiates the generation of inflammatory cytokines by intestinal epithelial cells during hyperoxia by inducing the expression of interleukin 17D.

Toxicology 2021 06 21;457:152820. Epub 2021 May 21.

ShengJing Hospital of China Medical University, Department of Gastroenterology and Medical Research Center, Liaoning Key Laboratory of Research and Application of Animal Models for Environmental and Metabolic Diseases, SanHao Street #36, HePing District, ShenYang, 110000, China. Electronic address:

Prolonged exposure to therapeutic hyperoxia can induce severe side effects on intestinal epithelial cells. Meanwhile, interleukin (IL)-17D secreted by intestinal epithelial cells, plays an important role in the mucosal immune system. Therefore, this study aimed to investigate the changes of IL-17D, IL-4 and IL-6 and the regulatory effect of nuclear factor erythroid 2-related factor 2 (Nrf2) on IL-17D, IL-4 and IL-6 under hyperoxia in human intestinal epithelial cells. To achieve this, NCM460 cells were exposed to an atmosphere containing 85 % oxygen (hyperoxia) for 24 h, 48 h, or 72 h; tert-butylhydroquinone (tBHQ) and ML385 were used as an Nrf2 activator and inhibitor, respectively. Immunohistochemical staining, western blot, and reverse transcription-quantitative polymerase chain reaction were performed to detect the expression levels of IL-17D, Nrf2, Kelch-like ECH-associated protein 1 (Keap1), IL-6, and IL-4 in NCM460 cells. Results showed that hyperoxia significantly increased the expression of IL-17D, Nrf2, IL-6, and IL-4, while decreasing that of Keap1. tBHQ further activated Nrf2 and promoted the expression of IL-17D, IL-6, and IL-4. Additionally, tBHQ aggravated hyperoxia-induced inflammation caused by hyperoxia. In contrast, ML385 completely inhibited the expression of Nrf2 and IL-17D, transiently inhibited IL-6 and IL-4 expression, and did not influence Keap1 expression. These results cumulatively demonstrate that hyperoxia aggravates the inflammatory response in intestinal epithelial cells by activating the Nrf2/IL-17D axis.
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http://dx.doi.org/10.1016/j.tox.2021.152820DOI Listing
June 2021

Moiré superlattices and related moiré excitons in twisted van der Waals heterostructures.

Chem Soc Rev 2021 Jun;50(11):6401-6422

School of Physics and Electronics, Hunan Key Laboratory for Super-microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, Hunan 410083, People's Republic of China.

Recent advances in moiré superlattices and moiré excitons, such as quantum emission arrays, low-energy flat bands, and Mott insulators, have rapidly attracted attention in the fields of optoelectronics, materials, and energy research. The interlayer twist turns into a degree of freedom that alters the properties of the systems of materials, and the realization of moiré excitons also offers the feasibility of making artificial exciton crystals. Moreover, moiré excitons exhibit many exciting properties under the regulation of various external conditions, including spatial polarisation, alternating dipolar to alternating dipolar moments and gate-dependence to gate voltage dependence; all are pertinent to their applications in nano-photonics and quantum information. But the lag in theoretical development and the low-efficiency of processing technologies significantly limit the potential of moiré superlattice applications. In this review, we systematically summarise and discuss the recent progress in moiré superlattices and moiré excitons, and analyze the current challenges, and put forward relevant recommendations. There is no doubt that further research will lead to breakthroughs in their application and promote reforms and innovations in traditional solid-state physics and materials science.
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http://dx.doi.org/10.1039/d0cs01002bDOI Listing
June 2021

Shannon entropy for time-varying persistence of cell migration.

Biophys J 2021 06 1;120(12):2552-2565. Epub 2021 May 1.

Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing, China. Electronic address:

Cell migration, which can be significantly affected by intracellular signaling pathways and extracellular matrix, plays a crucial role in many physiological and pathological processes. Cell migration is typically modeled as a persistent random walk, which depends on two critical motility parameters, i.e., migration speed and persistence time. It is generally very challenging to efficiently and accurately quantify the migration dynamics from noisy experimental data. Here, we introduce the normalized Shannon entropy (SE) based on the FPS of cellular velocity autocovariance function to quantify migration dynamics. The SE introduced here possesses a similar physical interpretation as the Gibbs entropy for thermal systems in that SE naturally reflects the degree of order or randomness of cellular migration, attaining the maximal value of unity for purely diffusive migration (i.e., SE = 1 for the most "random" dynamics) and the minimal value of 0 for purely ballistic dynamics (i.e., SE = 0 for the most "ordered" dynamics). We also find that SE is strongly correlated with the migration persistence but is less sensitive to the migration speed. Moreover, we introduce the time-varying SE based on the WPS of cellular dynamics and demonstrate its superior utility to characterize the time-dependent persistence of cell migration, which typically results from complex and time-varying intra- or extracellular mechanisms. We employ our approach to analyze experimental data of in vitro cell migration regulated by distinct intracellular and extracellular mechanisms, exhibiting a rich spectrum of dynamic characteristics. Our analysis indicates that the SE and wavelet transform (i.e., SE-based approach) offers a simple and efficient tool to quantify cell migration dynamics in complex microenvironment.
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http://dx.doi.org/10.1016/j.bpj.2021.04.026DOI Listing
June 2021

Deriving time-varying cellular motility parameters via wavelet analysis.

Phys Biol 2021 Jun 9;18(4). Epub 2021 Jun 9.

Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing, 401331, People's Republic of China.

Cell migration, which is regulated by intracellular signaling pathways (ICSP) and extracellular matrix (ECM), plays an indispensable role in many physiological and pathological process such as normal tissue development and cancer metastasis. However, there is a lack of rigorous and quantitative tools for analyzing the time-varying characteristics of cell migration in heterogeneous microenvironment, resulted from, e.g. the time-dependent local stiffness due to microstructural remodeling by migrating cells. Here, we develop a wavelet-analysis approach to derive the time-dependent motility parameters from cell migration trajectories, based on the time-varying persistent random walk model. In particular, the wavelet denoising and wavelet transform are employed to analyze migration velocities and obtain the wavelet power spectrum. Subsequently, the time-dependent motility parameters are derived via Lorentzian power spectrum. Our results based on synthetic data indicate the superiority of the method for estimating the intrinsic transient motility parameters, robust against a variety of stochastic noises. We also carry out a systematic parameter study and elaborate the effects of parameter selection on the performance of the method. Moreover, we demonstrate the utility of our approach via analyzing experimental data ofcell migration in distinct microenvironments, including the migration of MDA-MB-231 cells in confined micro-channel arrays and correlated migration of MCF-10A cells due to ECM-mediated mechanical coupling. Our analysis shows that our approach can be as a powerful tool to accurately derive the time-dependent motility parameters, and further analyze the time-dependent characteristics of cell migration regulated by complex microenvironment.
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http://dx.doi.org/10.1088/1478-3975/abfcadDOI Listing
June 2021

Association between different peritoneal dialysis catheter placement methods and short-term postoperative complications.

BMC Nephrol 2021 Apr 26;22(1):151. Epub 2021 Apr 26.

Department of Ultrasound, the Third Affiliated Hospital of Soochow University, 213003, Changzhou, China.

Background: Considering that current peritoneal dialysis has its own shortcomings, In this study, the Seldinger technique was modified to explore the relationship between different catheter placement methods of peritoneal dialysis and short-term postoperative complications.

Methods: We retrospectively analyzed the data of 157 patients who received peritoneal dialysis in the Department of Nephrology of our hospital from January 2017 to December 2019. According to different catheter placement methods, the patients were divided into three groups: 111 cases of open surgery technique, 23 cases of Seldinger technique, and 23 cases of modified Seldinger technique (ultrasound-guided Veress needle puncture). The general data, laboratory indexes, and abdominal infection and catheter-related complications within one month postoperatively were collected.

Results: There were 48 (31.0 %) cases of complications in 157 patients within one month postoperatively, which were mainly catheter-related complications (45 cases, 29.0 %). The incidence of catheter tip peritoneal drift (catheter migration) in the three groups was 27.3 %, 39.1 %, and 9.1 %, respectively, with no significant difference between groups (P = 0.069). Univariate logistic regression analysis showed that the systolic blood pressure, history of abdominal and pelvic surgery, creatinine, and modified Seldinger technique were possible impact factors of catheter migration (P < 0.10). After fully adjusting for confounding factors, Compared with the open surgery group, the modified Seldinger method group significantly reduced the risk of catheter migration with an OR of 0.161 (95 % confidence interval: 0.027-0.961, P = 0.045); However, the difference between the Seldinger method group and the open surgery group was not significant, with an OR of 1.061 (95 % confidence interval: 0.308-3.649, P = 0.926). Curve fitting showed that the average incidence of catheter migration in the three groups was 27.3 % (95% CI: 15.9-42.7 %), 28.5 % (95% CI: 10.7-56.9 %), and 5.7 % (95% CI: 1.0-27.0 %); the modified Seldinger method has the lowest average incidence of catheter migration.

Conclusions: Modified Seldinger technique can significantly reduce catheter-related short-term complications after peritoneal dialysis, and it is especially effective in reducing the incidence of catheter migration. Modified Seldinger technique is a safe and feasible method for the placement of a peritoneal dialysis catheter.
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http://dx.doi.org/10.1186/s12882-021-02340-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074448PMC
April 2021

Is telemedicine the answer to rural expansion of medication treatment for opioid use disorder? Early experiences in the feasibility study phase of a National Drug Abuse Treatment Clinical Trials Network Trial.

Addict Sci Clin Pract 2021 04 20;16(1):24. Epub 2021 Apr 20.

Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA.

Telemedicine (TM) enabled by digital health technologies to provide medical services has been considered a key solution to increasing health care access in rural communities. With the immediate need for remote care due to the COVID-19 pandemic, many health care systems have rapidly incorporated digital technologies to support the delivery of remote care options, including medication treatment for individuals with opioid use disorder (OUD). In responding to the opioid crisis and the COVID-19 pandemic, public health officials and scientific communities strongly support and advocate for greater use of TM-based medication treatment for opioid use disorder (MOUD) to improve access to care and have suggested that broad use of TM during the pandemic should be sustained. Nevertheless, research on the implementation and effectiveness of TM-based MOUD has been limited. To address this knowledge gap, the National Drug Abuse Treatment Clinical Trials Network (CTN) funded (via the NIH HEAL Initiative) a study on Rural Expansion of Medication Treatment for Opioid Use Disorder (Rural MOUD; CTN-0102) to investigate the implementation and effectiveness of adding TM-based MOUD to rural primary care for expanding access to MOUD. In preparation for this large-scale, randomized controlled trial incorporating TM in rural primary care, a feasibility study is being conducted to develop and pilot test implementation procedures. In this commentary, we share some of our experiences, which include several challenges, during the initial two-month period of the feasibility study phase. While these challenges could be due, at least in part, to adjusting to the COVID-19 pandemic and new workflows to accommodate the study, they are notable and could have a substantial impact on the larger, planned pragmatic trial and on TM-based MOUD more broadly. Challenges include low rates of identification of risk for OUD from screening, low rates of referral to TM, digital device and internet access issues, workflow and capacity barriers, and insurance coverage. These challenges also highlight the lack of empirical guidance for best TM practice and quality remote care models. With TM expanding rapidly, understanding implementation and demonstrating what TM approaches are effective are critical for ensuring the best care for persons with OUD.
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http://dx.doi.org/10.1186/s13722-021-00233-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8056373PMC
April 2021

Establishment of a prediction model for early and mid-term complications for patients undergoing catheter insertion for peritoneal dialysis.

J Int Med Res 2021 Apr;49(4):3000605211004524

Department of Ultrasound, the Third Affiliated Hospital of Soochow University, Changzhou, China.

Objective: To investigate the factors involved in early and mid-term complications after catheter insertion for peritoneal dialysis and to establish prediction models.

Methods: A total of 158 patients with peritoneal dialysis in the Department of Nephrology of our hospital were retrospectively analyzed. General information, laboratory indices, early complications (within 1 month after the operation), mid-term complications (1-6 months after the operation), and other relevant data were recorded. Multivariate logistic regression analysis was performed to establish a prediction model of complications and generate a nomogram. Receiver operating characteristic (ROC) curve analysis was used to evaluate the efficacy of the model.

Results: Among the patients, 48 (30.8%) had early complications, which were mainly catheter-related complications, and 29 (18.4%) had mid-term complications, which were mainly abdominal infection and catheter migration. We constructed a prediction model for early complications (area under the curve = 0.697, 95% confidence interval: 0.609-0.785) and mid-term complications (area under the curve = 0.730, 95% confidence interval: 0.622-0.839). The sensitivity was 0.750 and 0.607, and the specificity was 0.589 and 0.765, respectively.

Conclusions: Our prediction model has clinical significance for risk assessment of early and mid-term complications and prevention of complications after catheterization for peritoneal dialysis.
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http://dx.doi.org/10.1177/03000605211004524DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8059045PMC
April 2021

The relationship between plasma taurine levels in early pregnancy and later gestational diabetes mellitus risk in Chinese pregnant women.

Sci Rep 2021 Apr 12;11(1):7993. Epub 2021 Apr 12.

Department of Clinical Laboratory, Peking Union Medical College Hospital, Peking Union Medical College Hospital, China Academic Medical Science and Peking Union Medical College, Beijing, 100730, People's Republic of China.

Taurine is a sulfur-containing amino acid that plays an important role in glucose homeostasis. However, it remains unknown whether the plasma concentration of taurine affects the risk of later gestational diabetes mellitus (GDM) development. We recruited 398 singleton-pregnancy women and followed up them during the course of pregnancy. We measured the plasma concentrations of taurine based on blood samples collected at nine-week gestation on average and obtained the data regarding both mothers and their infants from medical records. There was a significant increment in the mean value of HOMA-β across the tertiles of plasma taurine in multiparous women rather than in primiparous women. After adjustment for confounders, an increase of plasma taurine was nominally and significantly associated with a decrease risk of GDM; moreover, women with plasma taurine concentrations in the lowest tertile and in the second tertile had a higher risk of GDM than did those with plasma taurine in the top tertile in multiparous women other than primiparous women. Plasma taurine level seems to be associated with insulin secretion in early pregnancy and be more closely associated with β-cell function and the risk of GDM development in multiparas in comparison to primiparas.
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http://dx.doi.org/10.1038/s41598-021-87178-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8041762PMC
April 2021

Enhancement of enzyme activities and VFA conversion by adding Fe/C in two-phase high-solid digestion of food waste: Performance and microbial community structure.

Bioresour Technol 2021 Jul 17;331:125004. Epub 2021 Mar 17.

Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China. Electronic address:

Two-phase high-solid digestion is conducive to the degradation of food waste. In this study, Fe/C was added in high-solid digestion in different acidification and/or methanogenic phase. The experimental results indicated that it significantly increased the cumulative yield of biomethane. When Fe/C was added to the acidification phase only and both the acidification and methanogenic phases, the biomethane yield reached 474.07 ± 7.03 and 475.47 ± 4.68 mL·g VS , respectively, and the biodegradation rate reached 87.30% and 87.58%, respectively, indicating that Fe/C had mainly effect on the performance of acidification phase. In a two-phase anaerobic fermentation system, the activity of dehydrogenases and the concentration of coenzyme F were 2.23-2.95 mg·g·h and 0.0063-0.0294 mol·g volatile solids, respectively. Additionally, the archaeal communities production pathway of methane from using acetic acid to using hydrogen as the reactant.
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http://dx.doi.org/10.1016/j.biortech.2021.125004DOI Listing
July 2021

The nucleolus functions as the compartment for histone H2B protein degradation.

iScience 2021 Apr 2;24(4):102256. Epub 2021 Mar 2.

Laboratory of Molecular and Cellular Biology, School of Forensic Sciences, Xi'an Jiao Tong University Health Science Center, Xi'an, Shaanxi 710061, PR China.

Histones are main components of chromatin, and the protein levels of histones significantly affect chromatin assembly. However, how histone protein levels are regulated, especially whether and how histones are degraded, is largely unclear. Here, we found that histone H2B is mainly degraded through the proteasome-mediated pathway, and the lysine-120 site of H2B is essential for its K48-linked polyubiquitination and degradation. Moreover, the degradation-impaired H2BK120R mutant shows an increased nucleolus localization, and inhibition of the proteasome results in an elevated nucleolus distribution of wild-type H2B, which is similar to that of H2BK120R mutants. More importantly, the nucleolus fractions can ubiquitinate and degrade the purified H2B , suggesting that the nucleolus, in addition to its canonical roles regulating ribosome genesis and protein translation, likely associates with H2B degradation. Therefore, these findings revealed a novel mechanism for the regulation of H2B degradation in which a nucleolus-associated proteasome pathway is involved.
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http://dx.doi.org/10.1016/j.isci.2021.102256DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7995529PMC
April 2021

Direct observation of enhanced performance in suspended ReS photodetectors.

Opt Express 2021 Feb;29(3):3567-3574

Rhenium disulfide (ReS) has emerged as a promising material for future optoelectric applications due to its extraordinary electrical, mechanical, and optoelectrical properties. However, the ReS-based photodetectors are severely restricted by their slow response speed (>10 s). Here, we demonstrate a high-performance polarization-sensitive photodetector based on suspended ReS. Such a transistor shows an n-type behavior with the mobility of about 14.1 cmVs, an on/off ratio of 10, and a responsivity of 0.22 A/W. Benefitting from well-developed contact between Au and the ReS channel and reduced interface scattering from the Si substrate, the response time of the device can be as short as 83.5 and 325.3µs, respectively, which are three orders of magnitude faster than that reported earlier. Furthermore, the suspended ReS photodetector also has the capability to detect polarized light (I/I ≈ 1.4 at 532 nm) due to the robust in-plane anisotropy of the material. These findings offer an efficient approach for improving the performance of ReS-based photodetectors.
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http://dx.doi.org/10.1364/OE.415060DOI Listing
February 2021

Overexpression of KcNHX1 gene confers tolerance to multiple abiotic stresses in Arabidopsis thaliana.

J Plant Res 2021 May 15;134(3):613-623. Epub 2021 Mar 15.

National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.

Abiotic stresses such as drought, salinity, and heat affect plant growth and development. Karelinia caspica is a unique perennial herb that grows in desert area for a long time and has strong tolerance to environmental stresses. In order to explore the functions of the Na/H antiporter gene from eremophyte K. caspica (KcNHX1) in the abiotic stress response of K. caspica and the underlying regulatory mechanisms, we constructed a vector overexpressing KcNHX1 and transformed it into Arabidopsis thaliana. The physiological results showed that the overexpression of KcNHX1 in A. thaliana not only enhanced the plant's tolerance to salt stress, but also enhanced its tolerance to drought and heat stress at the seedling stage. In addition, KcNHX1-overexpressing plants exhibited enhanced reproductive growth under high temperature, which was mediated by increased auxin accumulation. Taken together, our results indicate that KcNHX1 from an eremophyte can be used as a candidate gene to improve multiple stress tolerance in other plants.
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http://dx.doi.org/10.1007/s10265-021-01280-wDOI Listing
May 2021

A Direct and Sensitive Method for Determination of 5-Fluorouracil in Colorectal Cancer Cells: Evaluating the Effect of Stromal Cell on Drug Resistance of Cancer Cells.

J Anal Methods Chem 2021 25;2021:6689488. Epub 2021 Feb 25.

Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.

Fibroblasts in the stroma play a critical role in tumor evolution. In this study, we assessed the influence of colonic fibroblasts on colon cancer cells treated with 5-fluorouracil (5-FU), and mouse colon cancer cell lines MC38 and colonic fibroblasts NIH3T3 were used in this study. A sensitive and rapid UHPLC-MS/MS method for the quantitation of 5-FU from the cell and their medium has been successfully developed and validated. The cells were lysed with methanol, and the mixture was evaporated and then redissolved to extract intracellular 5-FU. The analysis was performed on UHPLC-MS/MS using an Atlantis T3-C18 column (3 m, 2. 1 ∗ 100 mm) and gradient elution with acetonitrile and 0.1% formic acid in water. Method validation included the following parameters: the matrix effect range 88.82%-93.64% and the recovery range 93.52%-94.56%. The intraday and interday precision and accuracy were <11% and within ±6%, and the stability, specificity, carry-over, dilution effect, and linearity all conformed to the criteria. The method was applied to detect the concentration of 5-FU inside cells and cell culture medium. The preliminary results present that NIH3T3 could enhance the drug resistance of MC38 to 5-FU with a decreased intracellular concentration of 5-FU in MC38, which showed a positive relationship with NIH3T3 number.
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http://dx.doi.org/10.1155/2021/6689488DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7932793PMC
February 2021

New views on endothelial dysfunction in gestational hypertension and potential therapy targets.

Drug Discov Today 2021 Jun 4;26(6):1420-1436. Epub 2021 Mar 4.

First Hospital of Soochow University & Maternal and Child Health Care Hospital of Wuxi, Jiangsu, China. Electronic address:

The placenta has vital roles in metabolite exchange, fetal growth, and pre-eclampsia (PE). In this review, we discuss the pathogenesis of hypertension in pregnancy, focusing on four major theories to explain PE, discussing endothelial roles in those theories. We focus in particular on the roles of nitric oxide (NO) and prostacyclin (PGI) in placental endothelium, and propose new hypotheses for the influence and mechanisms of endothelial NO and PGI signaling pathways in PE.
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http://dx.doi.org/10.1016/j.drudis.2021.03.001DOI Listing
June 2021

The role of emotions as mechanisms of mid-test warning messages during personality testing: A field experiment.

J Appl Psychol 2021 Feb 25. Epub 2021 Feb 25.

Lee Kong Chian School of Business.

This study focuses on the role of emotions in personnel selection and faking research. In particular, we posit that emotions are likely to be activated when applicants receive warning messages from organizations. Drawing on Nabi (Nabi, , 9, 1999, 292) cognitive-functional model of discrete negative emotions, we propose and empirically test the effects of three discrete negative emotions (guilt, fear, and anger) triggered by a warning message during a personality test on personality score accuracy and perceived test fairness. Participants in this within-subjects field experiment were 1,447 applicants for graduate school at a large public university in China. They completed two parallel forms of a personality test: one within a selection context, and another within a developmental context 6 months later as a baseline measure. In the selection context, a warning (or a control) message was randomly assigned to participants during the personality test. Emotions and perceived test fairness were measured after the test was completed. Results indicated that guilt, fear, and anger each played a unique role. Guilt explained how mid-test warnings improved personality score accuracy among fakers, whereas fear accounted for why nonfakers over-corrected their personality scores. Finally, anger explained why the mid-test warnings reduced perceived test fairness for both fakers and nonfakers. Theoretical and practical implications are discussed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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http://dx.doi.org/10.1037/apl0000885DOI Listing
February 2021

Giant nonlinear optical activity in two-dimensional palladium diselenide.

Nat Commun 2021 Feb 17;12(1):1083. Epub 2021 Feb 17.

School of Physics and Electronics, Hunan Key Laboratory for Super-microstructure and Ultrafast Process, Central South University, Changsha, Hunan, People's Republic of China.

Nonlinear optical effects in layered two-dimensional transition metal chalcogenides have been extensively explored recently because of the promising prospect of the nonlinear optical effects for various optoelectronic applications. However, these materials possess sizable bandgaps ranging from visible to ultraviolet region, so the investigation of narrow-bandgap materials remains deficient. Here, we report our comprehensive study on the nonlinear optical processes in palladium diselenide (PdSe) that has a near-infrared bandgap. Interestingly, this material exhibits a unique thickness-dependent second harmonic generation feature, which is in contrast to other transition metal chalcogenides. Furthermore, the two-photon absorption coefficients of 1-3 layer PdSe (β ~ 4.16 × 10, 2.58 × 10, and 1.51 × 10 cm GW) are larger by two and three orders of magnitude than that of the conventional two-dimensional materials, and giant modulation depths (α ~ 32%, 27%, and 24%) were obtained in 1-3 layer PdSe. Such unique nonlinear optical characteristics make PdSe a potential candidate for technological innovations in nonlinear optoelectronic devices.
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http://dx.doi.org/10.1038/s41467-021-21267-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7889859PMC
February 2021

Accuracy and feasibility of 3D-printed custom open trays for impressions of multiple implants: A self-controlled clinical trial.

J Prosthet Dent 2021 Feb 13. Epub 2021 Feb 13.

Professor, Department of Oral Implantology, Peking University School and Hospital of Stomatology, Beijing, PR China. Electronic address:

Statement Of Problem: Three-dimensionally printed custom open trays have become a popular option in clinical implant dentistry because of advantages such as individualization, efficiency, and effectiveness. However, clinical evidence on their accuracy and feasibility is lacking.

Purpose: The purpose of this clinical study was to evaluate the accuracy and feasibility for impressions of multiple implants by using 3D-printed custom open trays versus conventional custom open trays.

Material And Methods: Twenty-two partially edentulous individuals needing impression making for restorations supported by multiple implants were enrolled. Two types of custom open trays were made for each participant, a 3D-printed tray (test) and a conventional tray (control). With a splinted technique, silicone definitive impressions were obtained with the 2 custom open trays and poured with Type IV dental stone. Impression accuracy (primary outcome) was evaluated by measuring linear distances and the marginal gaps between the implant replicas and verification devices on the test and control casts. Clinical tray fit, impression quality, and cast quality were rated by an independent technician through a visual analog scale (VAS). The fabrication time and cost of the 2 types of custom open trays were recorded. The feasibility of 3D-printed trays was determined from these outcomes. The paired Student t test and Wilcoxon rank-sum tests were used for statistical analysis (α=.05).

Results: For impression accuracy, no statistically significant difference was found between test and control groups (P>.05). In terms of clinical tray fit, impression quality, and cast quality, no statistically significant difference was found (all P>.05). Regarding fabrication time and cost, the test group (57.65 ±6.49 minutes, 0.37 ±0.07 United States dollars [USD]) exhibited superiority over the control group (101.96 ±2.92 minutes, 4.41 ±0.37 USD) (both P<.001).

Conclusions: Within the limitations of this study, the 3D-printed custom open trays were clinically accurate, efficient, and cost-effective for impressions of multiple implants.
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http://dx.doi.org/10.1016/j.prosdent.2020.11.016DOI Listing
February 2021

MiR-181d-5p regulates implant surface roughness-induced osteogenic differentiation of bone marrow stem cells.

Mater Sci Eng C Mater Biol Appl 2021 Feb 16;121:111801. Epub 2020 Dec 16.

Department of Oral Implantology, Peking University School and Hospital of Stomatology, Beijing 100081, PR China. Electronic address:

Constructing moderate surface roughness is a widely used, non-toxic, cost-effective, and outcome-predictable approach to accelerate implant osteointegration in clinical settings. MicroRNAs (miRNAs) play vital regulatory roles in the osteogenic differentiation of bone marrow stem cells (BMSCs). However, their specific contribution to the influence of surface roughness on osteoblastic behavior remains unknown. Therefore, applying the smooth titanium surface as a control, a typical titanium surface with moderate roughness was prepared here to reveal the mechanism through which surface roughness regulates cell osteogenic behavior by altering miRNA expression. First, the morphology and roughness of two surfaces were characterized, and the enhanced osteogenic differentiation of BMSCs on rough surfaces was verified. Then, twenty-nine differentially expressed miRNAs in BMSCs cultured on different surfaces were selected via miRNA chip and corresponding functional prediction. After verifying the expression of these miRNAs using quantitative real-time polymerase chain reaction, four were considered eligible candidates. Among these, only miR-181d-5p significantly affected RUNX2 gene expression based on overexpression and knockdown experiments. From the osteogenesis-related gene and protein expression, as well as alkaline phosphatase and alizarin red experiments, we further confirmed that the downregulation of miR-181d-5p promoted osteogenic differentiation of BMSCs, and vice versa. In addition, rescue assays showed that the knockdown of miR-181d-5p improved the inferior osteogenesis observed on smooth surfaces, whereas the overexpression of miR-181d-5p suppressed the superior osteogenesis observed on rough surfaces. These results indicate that the moderate surface roughness of the implant stimulates the osteogenic differentiation of BMSCs by remarkably downregulating miR-181d-5p. These findings provide helpful information and a theoretical basis for the development of advanced implant materials for fast osteointegration.
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http://dx.doi.org/10.1016/j.msec.2020.111801DOI Listing
February 2021

Optimization of Cellulase Immobilization with Sodium Alginate-Polyethylene for Enhancement of Enzymatic Hydrolysis of Microcrystalline Cellulose Using Response Surface Methodology.

Appl Biochem Biotechnol 2021 Jul 5;193(7):2043-2060. Epub 2021 Feb 5.

Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.

A novel method of immobilizing cellulase on sodium alginate (SA)-polyethylene glycol (PEG) enabled the cellulase to be used repeatedly. The matrix of the immobilized cellulase was detected and characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. In comparison with SA-immobilized cellulase, the relative enzyme activity and immobilization rate increased by 25% and 18%, respectively. The application range of the immobilized enzyme in terms of temperature and pH was larger than that of the free enzyme, and its thermal stability increased. The immobilized enzyme was used in enzymatic hydrolysis, in which MCC was used as the substrate. The optimal conditions for enzymatic hydrolysis were as follows: the dosage of SA-PEG-immobilized cellulase was 3.55 g/g total solids of the substrate, the concentration of the substrate was 13.16%, and the pH was 5.11. In comparison with the yield of reducing sugars in the first round of hydrolysis of MCC by SA-immobilized cellulase, the yield in the hydrolysis of MCC by SA-PEG-immobilized cellulase increased by 133%. After five cycles of repeated use, the total yield of reducing sugars when MCC was hydrolyzed by SA-PEG-immobilized cellulase was similar to that achieved with free cellulase. In comparison with the free enzyme, the highest yield when the immobilized enzyme was used was 22.68%. Therefore, the immobilized cellulase exhibited high performance in enzymatic hydrolysis.
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http://dx.doi.org/10.1007/s12010-021-03517-9DOI Listing
July 2021