Publications by authors named "Zhi Wang"

1,584 Publications

  • Page 1 of 1

Pathologic Diagnosis and Genetic Analysis of Sequential Biopsy Following Coaxial Low-Power Microwave Thermal Coagulation For Pulmonary Ground-Glass Opacity Nodules.

Cardiovasc Intervent Radiol 2021 Apr 6. Epub 2021 Apr 6.

Department of Interventional Oncology, School of Medicine, Renji Hospital, Shanghai Jiaotong University, 160# Pujian Road, Shanghai, 200127, China.

Purpose: To evaluate the feasibility, safety, and diagnostic performance of sequential core-needle biopsy (CNB) technique following coaxial low-power microwave thermal coagulation (MTC) for ground-glass opacity (GGO) nodules.

Materials And Methods: From December 2017 to July 2019, a total of 32 GGOs (with diameter of 12 ± 4 mm) in 31 patients received two times of CNBs, both prior to and immediately after MTC at a power of 20 watts. The frequency and type of complications associated with CNBs were examined. The pathologic diagnosis and genetic analysis were performed for specimens obtained from the two types of biopsy.

Results: The technical success rates of pre- and post-MTC CNBs were 94% and 100%, respectively. The complication rate was significantly lower with post-MTC CNB as compared to pre-MTC CNB (42% versus 97%, p < 0.001). Larger amount of specimens could be obtained by post-MTC CNB. The pathological diagnosis rate of post-MTC CNB was significantly higher than that of pre-MTC CNB (100% versus 75%, p = 0.008), whereas the success rates of genetic analysis were comparable between the two groups (100% versus 84%, p = 0.063). Regular ablation could be further performed after post-MTC CNB to achieve local tumor control.

Conclusion: Sequential biopsy following coaxial low-power MTC can reduce the risk of complications and provide high-quality specimens for pulmonary GGOs. Combining this technique with standard ablation allows for simultaneous diagnosis and treatment within a single procedure.
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http://dx.doi.org/10.1007/s00270-021-02782-9DOI Listing
April 2021

Single-resonator, stable dual-longitudinal-mode optofluidic microcavity laser based on a hollow-core microstructured optical fiber.

Opt Express 2021 Mar;29(7):10077-10088

A single-resonator, stable dual-longitudinal-mode optofluidic microcavity laser based on a hollow-core microstructured optical fiber is proposed and experimentally demonstrated. The resonator and microfluidic channel are integrated in the hollow-core region of the fiber, inside which a hexagonal silica ring is used as the only resonator of the laser. Experimental results show that with mixing a small amount of Rhodamine B into a 1 mM Rhodamine 6G solution to form a dual-dye solution as a gain medium, the laser obtained by the method of lateral pumping can operate at dual longitudinal modes, with a threshold of 90 nJ/mm. By adjusting the concentration of Rhodamine B, the lasing wavelength of the laser and the power ratio of the two wavelengths can be controlled. And because the laser emission is co-excited by different kinds of dye molecules, the mode competition is diminished, enabling the simultaneously efficient optical gain and therefore lasing at dual longitudinal modes stably with a maximum lasing intensity fluctuation of 3.2% within 30 minutes even if the dual longitudinal modes have the same linear polarization states. This work can open up promising opportunities for diverse applications in biosensing and medical diagnosis with high sensitivity and integrated photonics with compact structure.
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http://dx.doi.org/10.1364/OE.418936DOI Listing
March 2021

On the Use of EBSD and Microhardness to Study the Microstructure Properties of Tungsten Samples Prepared by Selective Laser Melting.

Materials (Basel) 2021 Mar 4;14(5). Epub 2021 Mar 4.

Laser College of Engineering, Beijing University of Technology, Beijing 100124, China.

Additively manufactured tungsten and its alloys have been widely used for plasma facing components (PFCs) in future nuclear fusion reactors. Under the fusion process, PFCs experience a high-temperature exposure, which will ultimately affect the microstructural features, keeping in mind the importance of microstructures. In this study, microhardness and electron backscatter diffraction (EBSD) techniques were used to study the specimens. Vickers hardness method was used to study tungsten under different parameters. EBSD technique was used to study the microstructure and Kikuchi pattern of samples under different orientations. We mainly focused on selective laser melting (SLM) parameters and the effects of these parameters on the results of different techniques used to study the behavior of samples.
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http://dx.doi.org/10.3390/ma14051215DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7961342PMC
March 2021

Technical safety and efficacy of a blunt-tip microwave ablation electrode for CT-guided ablation of pulmonary ground-glass opacity nodules.

Eur Radiol 2021 Apr 2. Epub 2021 Apr 2.

Department of Interventional Oncology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160# Pujian Road, Shanghai, 200127, China.

Objectives: To evaluate the safety and technical efficacy of a customized blunt-tip microwave ablation (MWA) electrode for CT-guided ablation of pulmonary ground-glass opacity nodules (GGOs).

Materials And Methods: This was a retrospective before-after study. All consented patients with GGOs who underwent MWA treatment using conventional sharp-tip electrodes (group A) between January 2018 and December 2018 or new blunt-tip electrodes (group B) between January 2019 and December 2019 in our institution were included. The individual features of each patient and lesion, as well as technical and clinical information, were collected and analyzed.

Results: Sixteen (7 males, 9 females; mean age, 64.9 ± 12.3 years) and twenty-six (11 males, 15 females; mean age, 66.5 ± 10.7 years) patients were enrolled in groups A and B, respectively. The technique was successfully performed in all patients and a follow-up CT scan at 24 h after MWA showed that the technical efficacy rate was 100% in both groups. Twelve (75.0%) grade I complications were noted in group A, whereas 11 (42.3%) were noted in group B (p = 0.039, chi-square test). No bleeding occurred within the lesions in group B.

Conclusions: The blunt-tip MWA electrode is a safe and technically effective tool for ablating GGO lesions.

Key Points: • A new blunt-tip MWA electrode was used for CT-guided ablation of GGO lesions. • The blunt-tip MWA electrode could improve the safety of GGO ablation. • The technical efficacy of ablation was maintained by using the blunt-tip MWA electrode.
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http://dx.doi.org/10.1007/s00330-021-07774-4DOI Listing
April 2021

Giant gauge factor of Van der Waals material based strain sensors.

Nat Commun 2021 Apr 1;12(1):2018. Epub 2021 Apr 1.

School of Physics, Beijing Institute of Technology, Beijing, P. R. China.

There is an emergent demand for high-flexibility, high-sensitivity and low-power strain gauges capable of sensing small deformations and vibrations in extreme conditions. Enhancing the gauge factor remains one of the greatest challenges for strain sensors. This is typically limited to below 300 and set when the sensor is fabricated. We report a strategy to tune and enhance the gauge factor of strain sensors based on Van der Waals materials by tuning the carrier mobility and concentration through an interplay of piezoelectric and photoelectric effects. For a SnS sensor we report a gauge factor up to 3933, and the ability to tune it over a large range, from 23 to 3933. Results from SnS, GaSe, GeSe, monolayer WSe, and monolayer MoSe sensors suggest that this is a universal phenomenon for Van der Waals semiconductors. We also provide proof of concept demonstrations by detecting vibrations caused by sound and capturing body movements.
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http://dx.doi.org/10.1038/s41467-021-22316-8DOI Listing
April 2021

Logistic Regression Analysis of Conventional Ultrasound, and Contrast-Enhanced Ultrasound Characteristics: Is It Helpful in Differentiating Benign and Malignant Superficial Lymph Nodes?

J Ultrasound Med 2021 Apr 1. Epub 2021 Apr 1.

Department of Ultrasound, First Medical Center, Chinese People's Liberation Army General Hospital, Beijing, China.

Objectives: This study aimed to screen the significant sonographic features for differentiation of benign and malignant superficial lymph nodes (LNs) by logistic regression analysis and fit a model to diagnose LNs.

Methods: A total of 204 pathological LNs were analyzed retrospectively. All the LNs underwent conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) examinations. A total of 16 suspicious sonographic features were used to assess LNs. All variables that were statistically related to the diagnosis of LNs were included in the logistic regression analysis in order to ascertain the significant features of diagnosing LNs, and to establish a logistic regression analysis model.

Results: The significant features in the logistic regression analysis model of diagnosing malignant LNs were absence of echogenic hilus, age, and absence of hilum after enhancement. According to the results of logistic regression analysis, the formula to predict whether LNs were malignant was established. The area under the receiver operating curve (ROC) was 0.908 and the accuracy, sensitivity, and specificity were 85.0%, 92.9%, and 85.3%, respectively.

Conclusion: The logistic regression model for the significant sonographic features of conventional US and CEUS is an effective and accurate diagnostic tool for differentiating malignant and benign LNs.
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http://dx.doi.org/10.1002/jum.15711DOI Listing
April 2021

Molecular response uncovers neurotoxicity of Pardosa pseudoannulata exposed to cadmium pressure.

Environ Pollut 2021 Mar 22;280:117000. Epub 2021 Mar 22.

Division of Plant Sciences, University of Missouri, Columbia, MO, 65211, USA.

Cadmium (Cd) is a widely distributed heavy metal in south of China. Growing evidence indicates that systemic exposure to Cd, particularly the long-term exposure, may cause neurotoxic effects. Nevertheless, mechanisms underlying Cd neurotoxicity remain not completely understood. In this report, we investigated the neural alterations in the spider Pardosa pseudoannulata (Bösenberg and Strand, 1906) exposed to long-term Cd (LCd) and short-term Cd (SCd) pressure. Cd stress lowered foraging ability and prey consuming time in the spiders. In addition, enzymatic analysis results indicated that Cd exposure reduced the level of acetylcholinesterase at subcellular level. We then identified differentially expressed genes (DEGs) in the Cd exposed spiders using pairwise comparisons and found that a large number of DEGs were related to neurotransmitter receptors and ion transport and binding proteins. Notably, LCd exposure harbored more altered genes in ion transporter activity comparing with SCd exposure. From six K-means clusters, 53 putative transcriptional factors (TFs) belonging to 21 families were characterized, and ZBTB subfamily displayed the most distinctive alterations in the characterized genes, which is assumed to play a key role in the regulation of ion transmembrane process under Cd stress. A protein-to-protein interaction network constructed by the yielded DEGs also showed that ion and receptor binding activities were affected under long-term Cd exposure. Four key modules from the network indicated that Cd may further down-regulate energy metabolism pathway in spiders. Collectively, this comprehensive analysis provides multi-dimensional insights to understand the molecular response of spiders to Cd exposure.
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http://dx.doi.org/10.1016/j.envpol.2021.117000DOI Listing
March 2021

Recent Advances in Producing Sugar Alcohols and Functional Sugars by Engineering .

Front Bioeng Biotechnol 2021 11;9:648382. Epub 2021 Mar 11.

School of Chemical Engineering, Zhengzhou University, Zhengzhou, China.

The sugar alcohols and functional sugars have wide applications in food, pharmaceutical, and chemical industries. However, the smaller quantities of natural occurring sugar alcohols and functional sugars restricted their applications. The enzymatic and whole-cell catalyst production is emerging as the predominant alternatives. The properties of make it a promising sugar alcohol and functional sugar producer. However, there are still some issues to be resolved. As there exist reviews about the chemical structures, physicochemical properties, biological functions, applications, and biosynthesis of sugar alcohols and/or functional sugars in , this mini review will not only update the recent advances in enzymatic and microbial production of sugar alcohols (erythritol, D-threitol, and xylitol) and functional sugars (isomaltulose, trehalose, fructo-oligosaccharides, and galacto-oligosaccharides) by using recombinant but also focus on the studies of gene discovery, pathway engineering, expanding substrate scope, bioprocess engineering, and novel breeding methods to resolve the aforementioned issues.
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http://dx.doi.org/10.3389/fbioe.2021.648382DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992007PMC
March 2021

Metal-organic framework precursors derived Ni-doping porous carbon spheres for sensitive electrochemical detection of acetaminophen.

Talanta 2021 Jun 19;228:122228. Epub 2021 Feb 19.

College of Science, Hebei Agricultural University, Baoding, 071001, PR China. Electronic address:

The sensitive and selective determination of acetaminophen (AP) in the human body is highly desirable to ensure human health. In this work, nickel-doping nanoporous carbon (Ni/C) was fabricated by directly calcining Ni based metal-organic framework (Ni-MOF). The Ni/C based electrochemical sensor was developed for sensitive and selective determination of AP in human blood serum and urine samples. The prepared Ni/C composite possess plentiful catalytic active sites, ordered mesoporous structure and large specific surface area, which endow the constructed Ni/C sensor with a prominent performance for acetaminophen sensing. Under the optimal conditions, the developed method offered good linearity in the range of 0.20-53.75 μM with a low detection limit (S/N = 3) of 4.04 × 10 μM. The electrocatalytic performance of the sensor towards AP was further measured by differential pulse voltammetry and cyclic voltammetry. The results demonstrated that the Ni/C sensor can be feasibly employed for the determination of AP in human blood serum and urine samples with excellent anti-interference stability and good reproducibility. The research reveals a great promising of the Ni/C electrochemical sensor for clinical applications and paves a way for the construction of high-performance electrochemical sensors for AP determination.
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http://dx.doi.org/10.1016/j.talanta.2021.122228DOI Listing
June 2021

Carbon nanomaterials treated by combination of oxidation and flash for highly efficient solar water evaporation.

Chemosphere 2021 Mar 15;277:130248. Epub 2021 Mar 15.

Chemical Engineering Research Center, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin, 300072, China; State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin, 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin, 300072, China.

The high-efficiency solar evaporation is a potential technique to desalinate hypersaline wastewater and seawater to alleviate the global fresh water shortage. Photo-thermal agent and solar evaporator with low-cost raw materials, high photo-thermal conversion efficiency and simple-fast preparation methods is crucial to realize the industrial application of solar evaporation. Herein, carbon nanomaterial with higher light absorption and photo-thermal conversion efficiency than that of carbon black was obtained by combination treatment of carbon black with oxidation and flash illumination. In order to characterize the evaporation performance of the devices, a floating evaporator was fabricated with the carbon nanomaterial on the top of polyethylene foam wrapped with non-woven fabrics. The evaporation rate and photo-thermal conversion efficiency of evaporators were affected significantly by environmental temperature and humidity. At the environmental temperature of 19.5 °C, the evaporator fabricated with the combined treated carbon nanomaterial as photo-thermal agents presents a stable evaporation rate at 1.27 kg m h and solar evaporation efficiency at 78.7% under 1 kW m simulated sun illumination, which are higher than those of evaporator with carbon black (1.13 kg m h and 68.1%). The distilled water obtained from the solar evaporator met the standards of drinkable water. Overall, the experimental result demonstrates a great promise application of treated carbon nanomaterial as a photo-thermal agent in the field of seawater desalination and solar-energy collector.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130248DOI Listing
March 2021

Fabrication of microlenses with continuously variable numerical aperture through a temporally shaped femtosecond laser.

Opt Express 2021 Feb;29(3):4596-4606

We developed a novel method for fabricating microlenses and microlens arrays by controlling numerical aperture (NA) through temporally shaped femtosecond laser on fused silica. The modification area was controlled through the pulse delay of temporally shaped femtosecond laser. The final radius and sag height were obtained through subsequent hydrofluoric acid etching. Electron density was controlled by the temporally shaped femtosecond laser, and the maximum NA value (0.65) of a microlens was obtained in the relevant studies with femtosecond laser fabrication. Furthermore, the NA can be continuously adjusted from 0.1 to 0.65 by this method. Compared with the traditional methods, this method exhibited high flexibility and yielded microlenses with various NAs and microlens arrays to meet the different demands for microlens applications.
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http://dx.doi.org/10.1364/OE.411511DOI Listing
February 2021

The effectiveness of the laid-back position on lactation-related nipple problems and comfort: a meta-analysis.

BMC Pregnancy Childbirth 2021 Mar 24;21(1):248. Epub 2021 Mar 24.

Department of Nursing, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan, China.

Background: The importance of breastfeeding for maternal and child health is agreed upon worldwide. However, lactation-related nipple problems are common and are important factors affecting breastfeeding. Multiple studies recommended laid-back breastfeeding, but they are of various levels of quality, and the results are inconclusive.

Methods: We systematically searched the following twelve databases from inception to January 28,2020: Cochrane Library, EMBASE, Medline, Ovid, PubMed, Web of Science, CINAHL, Scopus, Chinese National Knowledge Infrastructure (CNKI), China Biology Medicine disc (CBM), WanFang, and VIP. All studies regarding laid-back breastfeeding or biological nurturing were considered, regardless of whether they were randomized controlled trials. Two trained investigators independently evaluated the quality of the selected articles and screened the data. All the data were analysed separately using Review Manager Version 5.3 and STATA/SE Version 15.1.

Results: A total of 12 studies involving 1936 groups of postpartum women and their newborns were included. The results of the meta-analysis showed that nipple pain (RR = 0.24; 95% CI 0.14, 0.40; p < 0.00001), nipple trauma (RR = 0.47; 95% CI 0.29, 0.75; p = 0.002) and correct latching position (RR = 1.22; 95% CI 1.11, 1.33; p < 0.0001) in the experimental groups were all better than those of the control groups, and the differences were statistically significant (p < 0.05), which indicates that the laid-back position has a positive effect on maternal breastfeeding. However, the results of position comfort showed that there was no statistical significance between the two groups (ES = 0.09; 95% CI -0.63, 0.81; p = 0.798).

Conclusion: Compared with traditional breastfeeding positions, the laid-back position has been proven to be related to a decreased incidence of nipple pain and nipple trauma and is seemingly conducive to the use of the correct latching position. It is suggested that the laid-back position is helpful in solving lactation-related nipple problems and can be recommended as a position for breastfeeding. However, no significant difference in position comfort was found between the two groups based on the current evidence, and further studies are still needed to validate these results due to the limitations of the included studies.
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http://dx.doi.org/10.1186/s12884-021-03714-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992330PMC
March 2021

C2-C3 vertebral disc angle: an analysis of patients with and without cervical spondylotic myelopathy.

Neurochirurgie 2021 Mar 20. Epub 2021 Mar 20.

Centre Hospitalier Universitaire de l'Université de Montréal, Canada.

Study Design: Retrospective analysis Objective: To define C2-C3 vertebral disc angle (VDA) in patients with and without cervical spondylotic myelopathy.

Summary Of Background Data: C2-C3 VDA is a new radiological index of cervical spine alignment. Recent studies have suggested that high post-operative values are associated with greater mechanical complications in patients with cervical spondylotic myelopathy. However, normative values for patients without myelopathy has yet to be defined.

Methods: Patients with and without cervical myelopathy between 2017 and 2019 were included. Inclusion criteria were patients above 18 years of age with antero-posterior (AP) and lateral (LAT) cervical x-rays. In the non-myelopathic group, patients were excluded if they had neurological symptoms or deficits, presence of cervical axial pain, previous spinal surgery, or diagnosis of either spondylolisthesis or scoliosis. In the myelopathic group, patients were excluded if they had previous spinal surgery. Radiological indices evaluated include: C2-C3 disc angle, C2-C7 Cobb angle, C7 sagittal vertical axis, T1 slope.

Results: 99 patients without myelopathy and 22 patients with myelopathy were identified and analyzed. In patients without myelopathy, the mean for C2-C3 VDA was 25.9 ± 7.9. For patients with myelopathy, pre-operative values were 24.4 ± 10.0 and 27.1 ± 7.9 post-operatively. No statistically significant differences were found between patients with and without myelopathy. C2-C3 disc angle was not correlated with age (R = -0.173).

Conclusion: This study did not find statistically significant differences in C2-C3 VDA values between patients with and without cervical myelopathy. This study provides normative data for C2-C3 vertebral disc angle in patients with and without cervical spondylotic myelopathy. Furthermore, C2-C3 vertebral disc angle may be independent from age.
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http://dx.doi.org/10.1016/j.neuchi.2021.02.013DOI Listing
March 2021

Tinker-HP: Accelerating Molecular Dynamics Simulations of Large Complex Systems with Advanced Point Dipole Polarizable Force Fields Using GPUs and Multi-GPU Systems.

J Chem Theory Comput 2021 Mar 23. Epub 2021 Mar 23.

Sorbonne Université, LCT, UMR 7616 CNRS, F-75005 Paris, France.

We present the extension of the Tinker-HP package (Lagardère, 2018, 9, 956-972) to the use of Graphics Processing Unit (GPU) cards to accelerate molecular dynamics simulations using polarizable many-body force fields. The new high-performance module allows for an efficient use of single- and multiple-GPU architectures ranging from research laboratories to modern supercomputer centers. After detailing an analysis of our general scalable strategy that relies on OpenACC and CUDA, we discuss the various capabilities of the package. Among them, the multiprecision possibilities of the code are discussed. If an efficient double precision implementation is provided to preserve the possibility of fast reference computations, we show that a lower precision arithmetic is preferred providing a similar accuracy for molecular dynamics while exhibiting superior performances. As Tinker-HP is mainly dedicated to accelerate simulations using new generation point dipole polarizable force field, we focus our study on the implementation of the AMOEBA model. Testing various NVIDIA platforms including 2080Ti, 3090, V100, and A100 cards, we provide illustrative benchmarks of the code for single- and multicards simulations on large biosystems encompassing up to millions of atoms. The new code strongly reduces time to solution and offers the best performances to date obtained using the AMOEBA polarizable force field. Perspectives toward the strong-scaling performance of our multinode massive parallelization strategy, unsupervised adaptive sampling and large scale applicability of the Tinker-HP code in biophysics are discussed. The present software has been released in phase advance on GitHub in link with the High Performance Computing community COVID-19 research efforts and is free for Academics (see https://github.com/TinkerTools/tinker-hp).
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http://dx.doi.org/10.1021/acs.jctc.0c01164DOI Listing
March 2021

Evaluation of the protective effect of lycopene on growth performance, intestinal morphology, and digestive enzyme activities of aflatoxinB challenged broilers.

Anim Sci J 2021 Jan;92(1):e13540

College of Animal Science and Technology, Yangzhou University, Yangzhou City, China.

The current study was conducted to investigate the protective efficiency of dietary lycopene (LYC) supplementation on growth performance, intestinal morphology, and digestive enzyme activities aflatoxinB (AFB ) challenged broilers. A total of 240 days old Arber across male broiler chicks were randomly allocated in five treatments and six replicates (eight birds per replicate); feed and water were provided ad libitum during the 42 days experiment. The treatment diets were as follows: (i) Basal diet (control), (ii) Basal diet + 100 µg/kg AFB contaminated diet, (iii) Basal diet + 100 µg/kg AFB  + 100 mg/kg LYC1, (iv) Basal diet + 100 µg/kg AFB  + 200 mg/kg LYC2, and (v) Basal diet + 100 µg/kg AFB  + 400 mg/kg LYC3. The results showed that the addition of LYC to AFB contaminated broiler diets significantly increased (p < .05) average daily gain (ADG) and decreased feed conversion ratio (FCR) compared to the AFB diet. AFB diet decreased the intestinal villus height (VH) and crypt depth ratio (VCR) while increasing the crypt depth (CD). However, dietary LYC supplemented diets relieved the intestinal morphological alterations. Dietary LYC supplementation (200 and 400 mg/kg) significantly improved (p < .05) intestinal digestive enzyme amylase and lipase activities with AFB contaminated diet. These findings suggested that LYC is a promising feed supplement in the broiler industry, alleviating the harmful effects of AFB .
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http://dx.doi.org/10.1111/asj.13540DOI Listing
January 2021

Tuning electron correlation in magic-angle twisted bilayer graphene using Coulomb screening.

Science 2021 03;371(6535):1261-1265

Department of Physics, Brown University, Providence, RI 02912, USA.

Controlling the strength of interactions is essential for studying quantum phenomena emerging in systems of correlated fermions. We introduce a device geometry whereby magic-angle twisted bilayer graphene is placed in close proximity to a Bernal bilayer graphene, separated by a 3-nanometer-thick barrier. By using charge screening from the Bernal bilayer, the strength of electron-electron Coulomb interaction within the twisted bilayer can be continuously tuned. Transport measurements show that tuning Coulomb screening has opposite effects on the insulating and superconducting states: As Coulomb interaction is weakened by screening, the insulating states become less robust, whereas the stability of superconductivity at the optimal doping is enhanced. The results provide important constraints on theoretical models for understanding the mechanism of superconductivity in magic-angle twisted bilayer graphene.
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http://dx.doi.org/10.1126/science.abb8754DOI Listing
March 2021

Histological and chemical damage induced by microcystin-LR and microcystin-RR on land snail Helix aspersa tissues after acute exposure.

Comp Biochem Physiol C Toxicol Pharmacol 2021 Mar 15;245:109031. Epub 2021 Mar 15.

Laboratory of Biodiversity and Ecosystems Pollution, Faculty of life and nature Sciences, University of Chadli Bendjedid, El Taref, Algeria; Thematic Agency for Research in Health Sciences, Oran, Algeria. Electronic address:

Microcystins (MCs) are the most common cyanotoxins with more than 200 variants. Among these cyanotoxins, microcystin-LR (MC-LR) and microcystin-RR (MC-RR) are the most studied congeners due to their high toxicity and frequent occurrence in surface waters. MC-LR has been detected in more than 75% of natural cyanobacteria bloom, along with other toxic and less toxic congeners. Accumulation of several microcystins variants (MC-LR and MC-RR) has been confirmed in aquatic snails exposed naturally or in the laboratory to toxic blooms. Thus, this paper aims to compare the biochemical and histological impact of both toxic variants (microcystin-LR and microcystin-RR) and their mixed form on a bioindicator, the land snail Helix aspersa. During experiments, snails were gavaged with a single acute dose (0.5 μg/g) of purified MC-LR, MC-RR, or mixed MC-LR + MC-RR (0.25 + 0.25 μg/g). After 96 h of exposure, effects on the hepatopancreas, kidney, intestine and lungs were assessed by histological observations and analysis of oxidative stress biomarkers. The results show that a small dose of MCs variants can increase the non-enzymatic antioxidant glutathione (GSH), inhibit glutathione-s-transferase (GST) level and trigger a defense system by activating glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD). Microcystin-RR causes serious anomalies in the hepatopancreas and kidney than Microcystin-LR. The organ most affected is the kidney. The damage caused by MC-LR + MC-RR is greater than that caused by single variants.
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http://dx.doi.org/10.1016/j.cbpc.2021.109031DOI Listing
March 2021

Ethnobotany and diversity of medicinal plants used by the Buyi in eastern Yunnan, China.

Plant Divers 2020 Dec 7;42(6):401-414. Epub 2020 Oct 7.

College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.

The Buyi are a socio-linguistic group in Yunnan Province of southwest China that have a long history of using medicinal plants as part of their indigenous medical system. Given the limited written documentation of the Buyi indigenous medical system, the objective of this paper is to document the medicinal plants of the Buyi and associated traditional knowledge and transmission. Field research was conducted in four villages in Lubuge Township of Luoping County in Yunnan Province using ethnobotanical methodologies including participatory observation, semi-structured interviews, key informant interviews, and focus group discussions to elicit information on medicinal plants. In total, 120 informants (including 15 key informants who are healers) were interviewed. This study found that a total of 121 medicinal plant species belonging to 64 families are used by the Buyi including by local healers to treat different diseases. Among the medicinal plants recorded in this study, 56 species (46%) have not previously been documented in the scientific literature as having medicinal value, highlighting the pressing need for ethnobotanical documentation in indigenous communities. The most frequently used medicinal part was the leaf (24.9% of documented plants), and the most common preparation method was decoction (62.8% of medicinal). Medicinal plants were mainly used to treat rheumatism (12.4% of plants), trauma and injuries (9.6%). The documented plants are also used for other non-medicinal purposes including food, fodder, fencing, and ornamental. In addition, 35 of the medicinal plants are considered poisonous and are used by local Buyi healers for medicine. The traditional Buyi beliefs and practices associated with the documented medicinal plants likely contributes to their conservation in the environments and around Buyi communities. This study further highlights that ethnomedicinal knowledge of the Buyi is at risk of disappearing due to increased introduction and use of modern medicine in Buyi communities, livelihood changes, rapid modernization, and urbanization. Research, policy, and community programs are urgently needed to conserve the biocultural diversity associated with the Buyi medical system including ethnobotanical knowledge towards supporting both environmental and human wellbeing.
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http://dx.doi.org/10.1016/j.pld.2020.09.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7936110PMC
December 2020

Anterolateral approach with two incisions versus posterior median approach in the treatment of middle- and distal-third humeral shaft fractures.

J Orthop Surg Res 2021 Mar 17;16(1):197. Epub 2021 Mar 17.

Department of Orthopedic Surgery, Hong Hui Hospital, Xi'an Jiaotong University College of Medicine, Xi'an, 710054, Shaanxi, China.

Background: The surgical approaches remain controversial for the treatment of middle and distal-third humeral shaft (MDTHS) fractures. This study compared clinical effects of the anterolateral approach with two incisions (AATI) and the posterior median approach (PMA) in the treatment of MDTHS fractures.

Methods: A retrospective analysis was carried out. One hundred sixty-six patients with MDTHS fractures were selected from January 2015 to January 2017 in Xi'an Hong Hui Hospital. According to surgical approaches, patients were divided into AATI (86 cases) and PMA group (80 cases). All patients were treated with open reduction and plate fixation. Operation indexes were compared, including incision length, operation time, and bleeding. Bryan-Morrey score was used to evaluate elbow joint function. Complication incidence was compared, such as incision infection, iatrogenic radial nerve injury, and nonunion.

Results: The AATI group showed smaller incision length, less bleeding, lower iatrogenic radial nerve injury rate, and better elbow function than that of PMA group (P<0.05).

Conclusions: The middle and distal-third humeral shaft fractures can be successfully cured by both approaches. Compared with the posterior median approach, it has better clinical effects of the anterolateral approach with two incisions, which is worthy of clinical application and promotion.
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http://dx.doi.org/10.1186/s13018-021-02355-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7967943PMC
March 2021

Different environmental requirements of female and male Siberian ibex, Capra sibirica.

Sci Rep 2021 Mar 16;11(1):6064. Epub 2021 Mar 16.

State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China.

In sexually dimorphic species, males and females may select different habitat for greater fitness. However, the key factors that play a leading role between sexes in habitat selection are still poorly understood. In this paper, we investigated the possible causes of the differences in habitat preference between male and female Siberian ibex (Capra sibirica) living in the Tianshan Mountains (China). Using the Maximum entropy model, we found that the ruggedness and elevation of the terrain were the most important factors affecting habitat selection in Siberian ibex. Females preferred the most rugged terrain to increase the security of their young and themselves, while males favored moderately rugged terrain to provide sufficient safety from predators, and availability of suitable forage simultaneously. Females used a wider variety of elevations to search for newly emerged vegetation for its higher nutritional value, while males preferred more elevated slopes to avoid the higher temperatures and greater presence of biting insects found at the lower elevations. In addition, females were associated more with rivers due to their higher water demands. The differences in habitat selection between Siberian ibex males and females depend on multiple considerations, but only a limited number of key factors determine their actual distribution.
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http://dx.doi.org/10.1038/s41598-021-85550-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7966747PMC
March 2021

Facile Fabrication of a Novel Copper Nanozyme for Efficient Dye Degradation.

ACS Omega 2021 Mar 23;6(9):6284-6291. Epub 2021 Feb 23.

Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education, College of Life Science, Jilin University, Changchun 130023, P. R. China.

In this study, a novel copper nanozyme (CNZ) was synthesized by a mild way and characterized by scanning electron microscopy and Fourier transform infrared spectroscopy (FTIR). The as-fabricated CNZ exhibited typical peroxidase activity toward 2, 2'-azinodi-(3-ethylbenzthiazoline)-6-sulfonate. We successfully applied CNZ for the degradation of methyl orange pollutants. Under the optimum conditions (pH, 3.0; , 60 °C; HO concentration, 200 mM; dosage of CNZ, 8 mg), 93% of the degradation rate could be obtained in less than 10 min. Furthermore, the nanozyme exhibited excellent reusability and storage stability. All these experimental results suggested that CNZ is a powerful catalyst for industrial wastewater treatment.
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http://dx.doi.org/10.1021/acsomega.0c05925DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7948215PMC
March 2021

Integrated analysis of competing endogenous RNA in esophageal carcinoma.

J Gastrointest Oncol 2021 Feb;12(1):11-27

Department of Thoracic Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.

Background: The Competing endogenous RNA (CeRNA) network plays important roles in the development and progression of multiple human cancers. Increasing attention has been paid to CeRNA in esophageal carcinoma (ESCA).

Methods: We explored The Cancer Genome Atlas (TCGA) database and then analyzed the RNAs of 142 samples to obtain long non-coding RNAs (lncRNAs), micro RNAs (miRNAs), and messenger RNAs (mRNAs) with different expression trends alongside the progress of ESCA. A series test of cluster (STC) analysis was carried out to identify a set of unique model expression tendencies. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to validate the function of key genes that were obtained from the STC analysis.

Results: Through our analysis, 272 lncRNAs, 87 miRNAs, and 692 mRNAs showed upward expression or downward expression trends, and these molecules were tightly involved in cell cycle, pathways in cancer, metabolic processes, and protein phosphorylation, among others. Ultimately, we constructed a CeRNA network containing a total of 71 lncRNAs, 56 miRNAs, and 125 mRNAs. The overall survival (OS) was analyzed using univariate Cox regression analysis to clarify the relationship between these key molecules from the CeRNA network and the prognosis of ESCA patients. Through survival analysis, we finally screened out two lncRNAs (DLEU2, RP11-890B15.3), three miRNAs (miR-26b-3p, miR-92a-3p, miR-324-5p), and one mRNA (SIK2) as crucial prognostic factors for ESCA.

Conclusions: The novel CeRNA network that we constructed will provide new novel prognostic biomarkers and therapeutic targets for patients with ESCA.
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http://dx.doi.org/10.21037/jgo-20-615DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7944153PMC
February 2021

Optimization, fabrication, and performance analysis of SMF-/MMF-based microfiber ball structure.

Appl Opt 2021 Feb;60(5):1196-1200

In this paper, four kinds of microfiber ball structure of different sizes, such as 330, 340, 350, and 360 µm were fabricated by single-mode fiber and multimode fiber, respectively. To test its performance, the reflected intensity was measured, and the results showed that the microfiber ball with the largest diameter of 360 µm had the maximum reflected intensity. The 360 µm microfiber ball was characterized by scanning electron microscope. This indicates that compared with a small-diameter microfiber ball, large-diameter microspheres are more suitable to be used as follow-up experimental objects, with the diameter of the fiber ball ranging from 330 to 360 µm.
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http://dx.doi.org/10.1364/AO.417358DOI Listing
February 2021

Fabrication techniques and stability analysis of SMF-/MMF-based differently tapered optical fiber structures.

Appl Opt 2021 Mar;60(7):2077-2082

In this work, fabrication techniques and optimization of single-mode fiber (SMF)- and multi-mode fiber (MMF)-based differently tapered optical fiber (TOF) structures are discussed. Further, taper characteristics such as diameter, transmitted intensity, and repeatability are analyzed. The results show that 25 µm TOF consists of lower transmitted intensity, meaning higher evanescent waves materialize at the tapered surface, which helps in suitable potential application of TOF as an optical fiber sensor.
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http://dx.doi.org/10.1364/AO.418875DOI Listing
March 2021

Magnetic resonance imaging follow-up can screen for soft tissue changes and evaluate the short-term prognosis of patients with developmental dysplasia of the hip after closed reduction.

BMC Pediatr 2021 Mar 8;21(1):115. Epub 2021 Mar 8.

Department of Radiology, Tianjin Hospital, Jiefangnan Road, Hexi District, Tianjin, 300211, TJ, China.

Background: Magnetic resonance imaging (MRI) can show the architecture of the hip joint clearly and has been increasingly used in developmental dysplasia of the hip (DDH) confirmation and follow-up. In this study, MRI was used to observe changes in the hip joints before and after closed reduction (CR) and to explore risk factors of residual acetabular dysplasia (RAD).

Methods: This is a prospective analysis of unilateral DDH patients with CR and spica cast in our hospital from October 2012 to July 2018. MRI and pelvic plain radiography were performed before and after CR. The labro-chondral complex (LCC) of the hip was divided into four types on MRI images. The variation in the thickening rate of the ligamentum teres, transverse ligaments, and pulvinar during MRI follow-up was analyzed, and the difference in cartilaginous acetabular head index was evaluated. The "complete relocation" rate of the femoral head was analyzed when the cast was changed for the last time, and the necrotic rate of the femoral head was evaluated after 18 months or more after CR. Lastly, the risk factors of RAD were analyzed.

Results: A total of 63 patients with DDH and CR were included. The LCC was everted before CR and inverted after CR, and the ligamentum teres, transverse ligaments, and pulvinar were hypertrophic before and after CR, and then gradually returned to normal shape. The cartilaginous acetabular head index gradually increased to normal values. Complete relocation was observed in 58.7% of femoral heads, while 8.6% had necrosis. The abnormalities in LCC was related to RAD (OR: 4.35, P = 0.03), and the rate of type 3 LCC in the RAD group was higher. However, the IHDI classification (P = 0.09); the "complete relocation" of femoral heads (P = 0.61); and hypertrophy of the ligamentum teres (P = 1.00), transverse ligaments (P = 1.00), and pulvinar (P = 1.00) were not related to RAD.

Conclusions: In this study, MRI can observe the variations of the abnormal soft tissue structures of the diseased hips after CR and spica casting, and can evaluate which hips will have RAD after CR. Therefore, we can utilize MRI in DDH patients appropriately.
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http://dx.doi.org/10.1186/s12887-021-02587-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7938578PMC
March 2021

ITM2A as a Tumor Suppressor and Its Correlation With PD-L1 in Breast Cancer.

Front Oncol 2020 12;10:581733. Epub 2021 Feb 12.

Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Background: High expression of integral membrane protein 2A (ITM2A) was reported to be associated with favorable prognosis in several solid tumors including breast cancer. This study aimed to investigate the role of ITM2A in breast cancer, especially in respect to tumor microenvironment.

Methods: ITM2A expression was evaluated based on qRT-PCR results on breast cancer specimens, as well as TCGA and GEO datasets. The influence of ITM2A expression on breast cancer cell proliferation and tumor growth were evaluated by CCK-8 assay, clonogenic assay, and murine xenograft models. Transwell assay was performed to observe the changes of invasion and migration capacity in breast cancer cells. To determine the biological functions of ITM2A, differentially expressed genes (DEGs) were screened based on RNA-sequencing data of MCF-7 cells overexpressed ITM2A. Then, functional annotation on DEGs was given by Gene Ontology and KEGG analysis. The stimulation on programmed cell death ligand 1 (PD-L1) expression when ITM2A overexpressed was determined by flow cytometry. Meanwhile, the correlation on expression levels between PD-L1 and ITM2A was tested qRT-PCR on 24 breast cancer tissues, as well as public database.

Results: We demonstrated that ITM2A was frequently downregulated in breast cancer. Patients with high expression levels of ITM2A had longer overall survival and relapse free survival. Overexpression of ITM2A inhibited proliferation and impaired cells capacity of invasion and migration and . The DEGs in breast cancer cells overexpressed ITM2A were found to be associated with immunity responses. Moreover, ITM2A was found to facilitate breast cancer cells to express PD-L1. The correlation between PD-L1 and ITM2A was verified with both qRT-PCR assay and public database. Additionally, it was found that breast cancer had higher ITM2A expression frequently had more tumor-infiltrating lymphocytes (TILs).

Conclusion: In summary, we found that high expression of ITM2A reduced the aggressivity of breast cancer cells and had a favorable effect on outcomes of patients with breast cancer. Moreover, ITM2A induced PD-L1 expression in breast cancer cells was accompanied with higher TILs numbers in tumor microenvironment.
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http://dx.doi.org/10.3389/fonc.2020.581733DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7928367PMC
February 2021

Development and Validation of a Nomogram for Lower Extremity Deep Venous Thrombosis in Patients after Acute Stroke.

J Stroke Cerebrovasc Dis 2021 Mar 3;30(5):105683. Epub 2021 Mar 3.

Department of Physical Medicine & Rehabilitation, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China; Departments of Neurology, The First Affiliated Hospital of Soochow University, 899 Pinghai Road, Suzhou 215000, Jiangsu, China.

Objectives: To develope and validate a nomogram to predict the probability of deep venous thrombosis (DVT) in patients after acute stroke during the first 14 days with clinical features and easily obtainable biochemical parameters.

Methods: This is a single-center prospective cohort study. The potential predictive variables for DVT at baseline were collected, and the presence of DVT was evaluated using ultrasonography within the first 14 days. Data were randomly assigned to either a modeling data set or a validation data set. Univariable and Multivariate logistic regression analysis was used to develop risk scores to predict DVT in the modeling data set and the area under the receiver operating characteristic curve to validate the score in the test data set, and nomogram and calibration curve were constructed by R project.

Results: A total of 1651 patients with acute stroke were enrolled in the study. The overall incidence of DVT after acute stroke within two weeks was 14.4%. Multivariable analysis detected older age (≥65 years),female gender, hemorrhagic stroke, malignancy, lower limb muscle strength<3 grade, Albumin<40 g·L and D-dimer>0.5 mg·L were highly predictive of 14-day risk of DVT. The AUC of the nomogram with these above-mentioned independent risk factors to predict the 14-day risk of DVT was 0.756 (95% CI, 0.712-0.812) and 0.811 (95%CI, 0.762-0.859) for the modeling cohort and external validation cohort, respectively. Moreover, the calibration of the nomogram showed a nonsignificant Hosmer-Lemeshow test statistic in the modeling (P = 0.250) and validation sets (P = 0.995). With respect to decision curve analyses, the nomogram exhibited preferable net benefit gains than the staging system across a wide range of threshold probabilities.

Conclusion: This nomogram had a good performance in predictive accuracy, discrimination capability, and clinical utility, which was helpful for clinicians to identify high-risk groups of DVT and formulate relevant prevention and treatment measures.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2021.105683DOI Listing
March 2021

Porous Semiconducting Polymers Enable High-Performance Electrochemical Transistors.

Adv Mater 2021 Apr 3;33(14):e2007041. Epub 2021 Mar 3.

Department of Chemistry and the Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA.

Organic polymer electrochemical transistors (OECTs) are of great interest for flexible electronics and bioelectronics applications owing to their high transconductance and low operating voltage. However, efficient OECT operation must delicately balance the seemingly incompatible materials optimizations of redox chemistry, active layer electronic transport, and ion penetration/transport. The latter characteristics are particularly challenging since most high-mobility semiconducting polymers are hydrophobic, which hinders efficient ion penetration, hence limiting OECT performance. Here, the properties and OECT response of a series of dense and porous semiconducting polymer films are compared, the latter fabricated via a facile breath figure approach. This methodology enables fast ion doping, high transconductance (up to 364 S cm ), and a low subthreshold swing for the hydrophobic polymers DPPDTT and P3HT, rivalling or exceeding the metrics of the relatively hydrophilic polymer, Pg2T-T. Furthermore, the porous morphology also enhances the transconductance of hydrophilic polymers, offering a general strategy for fabricating high-performance electrochemical transistors.
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http://dx.doi.org/10.1002/adma.202007041DOI Listing
April 2021

In vitro and ex vivo anti‑tumor effect and mechanism of Tucatinib in leukemia stem cells and ABCG2‑overexpressing leukemia cells.

Oncol Rep 2021 Mar 30;45(3):1142-1152. Epub 2020 Dec 30.

Department of Anesthesiology, Sun Yat‑Sen Memorial Hospital, Sun Yat‑Sen University, Guangzhou, Guangdong 510289, P.R. China.

Leukemia stem cells (LSCs), which evade standard chemotherapy, may lead to chemoresistance and disease relapse. The overexpression of ATP‑binding cassette subfamily G member 2 (ABCG2) is an important determinant of drug resistance in LSCs and it can serve as a marker for LSCs. Targeting ABCG2 is a potential strategy to selectively treat and eradicate LSCs, and, hence, improve leukemia therapy. Tucatinib (Irbinitinib) is a novel tyrosine kinase inhibitor, targeting ErbB family member HER2, and was approved by the Food and Drug Administration in April 2020, and in Switzerland in May 2020 for the treatment of HER2‑positive breast cancer. In the present study, the results demonstrated that tucatinib significantly improved the efficacy of conventional chemotherapeutic agents in ABCG2‑overexpressing leukemia cells and primary leukemia blast cells, derived from patients with leukemia. In addition, tucatinib markedly decreased the proportion of leukemia stem cell‑like side population (SP) cells. In SP cells, isolated from leukemia cells, the intracellular accumulation of Hoechst 33342, which is an ABCG2 substrate, was significantly elevated by tucatinib. Furthermore, tucatinib notably inhibited the efflux of [3H]‑mitoxantrone and, hence, there was a higher level of [3H]‑mitoxantrone in the HL60/ABCG2 cell line. The result from the ATPase assay revealed that tucatinib may interact with the drug substrate‑binding site and stimulated ATPase activity of ABCG2. However, the protein expression level and cellular location of ABCG2 were not affected by tucatinib treatment. Taken together, these data suggested that tucatinib could sensitize conventional chemotherapeutic agents, in ABCG2‑overexpressing leukemia cells and LSCs, by blocking the pump function of the ABCG2 protein. The present study revealed that combined treatment with tucatinib and conventional cytotoxic agents could be a potential therapeutic strategy in ABCG2‑positive leukemia.
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http://dx.doi.org/10.3892/or.2020.7915DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7859976PMC
March 2021

Large-Scale Affine Matrix Rank Minimization With a Novel Nonconvex Regularizer.

IEEE Trans Neural Netw Learn Syst 2021 Mar 1;PP. Epub 2021 Mar 1.

Low-rank minimization aims to recover a matrix of minimum rank subject to linear system constraint. It can be found in various data analysis and machine learning areas, such as recommender systems, video denoising, and signal processing. Nuclear norm minimization is a dominating approach to handle it. However, such a method ignores the difference among singular values of target matrix. To address this issue, nonconvex low-rank regularizers have been widely used. Unfortunately, existing methods suffer from different drawbacks, such as inefficiency and inaccuracy. To alleviate such problems, this article proposes a flexible model with a novel nonconvex regularizer. Such a model not only promotes low rankness but also can be solved much faster and more accurate. With it, the original low-rank problem can be equivalently transformed into the resulting optimization problem under the rank restricted isometry property (rank-RIP) condition. Subsequently, Nesterov's rule and inexact proximal strategies are adopted to achieve a novel algorithm highly efficient in solving this problem at a convergence rate of O(1/K), with K being the iterate count. Besides, the asymptotic convergence rate is also analyzed rigorously by adopting the Kurdyka-Łojasiewicz (KL) inequality. Furthermore, we apply the proposed optimization model to typical low-rank problems, including matrix completion, robust principal component analysis (RPCA), and tensor completion. Exhaustively empirical studies regarding data analysis tasks, i.e., synthetic data analysis, image recovery, personalized recommendation, and background subtraction, indicate that the proposed model outperforms state-of-the-art models in both accuracy and efficiency.
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http://dx.doi.org/10.1109/TNNLS.2021.3059711DOI Listing
March 2021