Publications by authors named "Zhen Ma"

252 Publications

Identification of immune-related genes that predict prognosis and risk of bladder cancer: bioinformatics analysis of TCGA database.

Aging (Albany NY) 2021 Jul 30;13(undefined). Epub 2021 Jul 30.

Binzhou Medical University, Binzhou, China.

Background: Bladder cancer (BLCA) is the major tumor of the urinary system, and immune-related genes (IRGs) contribute significantly to its initiation and prognosis.

Results: A total of 51 prognostic IRGs significantly associated with overall survival were identified. Functional enrichment analysis revealed that these genes were actively involved in tumor-related functions and pathways. Using multivariate Cox regression analysis, we detected 11 optimal IRGs (ADIPOQ, PPY, NAMPT, TAP1, AHNAK, OLR1, PDGFRA, IL34, MMP9, RAC3, and SH3BP2). We validated the prognostic value of this signature in two validation cohorts: GSE13507 (n = 165) and GSE32894 (n = 224). Furthermore, we performed a western blot and found that the expression of these IRGs matched their mRNA expression in TCGA. Moreover, correlations between risk score and immune-cell infiltration indicated that the prognostic signature reflected infiltration by several types of immune cells.

Conclusion: We identified and validated an 11-IRG-based risk signature that may be a reliable tool to evaluate the prognosis of BLCA patients and help to devise individualized immunotherapies.

Methods: Bioinformatics analysis was performed using TCGA and ImmPort databases. Cox regression was used to identify prognostic signatures. Two external GEO cohorts and western blotting of samples were performed to validate the IRG signature.
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http://dx.doi.org/10.18632/aging.203333DOI Listing
July 2021

Rapid screening and characterization of glucosinolates in 25 Brassicaceae tissues by UHPLC-Q-exactive orbitrap-MS.

Food Chem 2021 Jun 30;365:130493. Epub 2021 Jun 30.

Experimental Centre, Shandong University of Traditional Chinese Medicine, Jinan 250355, China; Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Jinan 250355, China; Shandong Provincial Key Laboratory of Traditional Chinese Medicine for Basic Research, Shandong University of Traditional Chinese Medicine, Jinan 250355, China. Electronic address:

Glucosinolates (GSLs) are secondary plant metabolites that occur mainly in the Brassicaceae plants, which are desirable compounds in human foods due to their diverse biological activities. In this study, we developed an integrated data filtering and identification strategy to characterize the GSLs. An in-depth GSLs profiling was performed on 25 commonly Brassicaceae tissues in Jinan, China. By comparison with the reference standards and previous researches, we tentatively identified 47 GSLs including 8 unknown ones. The GSLs profiles of 25 Brassicaceae tissues were established, and 11 markers of GSLs could be used to distinguish the Brassica and Raphanus. This approach enables accurately characterization the GSLs of Brassicaceae tissues, and demonstrates the potential of GSLs profiles for Brassicaceae species discrimination.
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http://dx.doi.org/10.1016/j.foodchem.2021.130493DOI Listing
June 2021

PER1 Is a Prognostic Biomarker and Correlated With Immune Infiltrates in Ovarian Cancer.

Front Genet 2021 17;12:697471. Epub 2021 Jun 17.

Department of Obstetrics, Gansu Province Maternity and Child-Care Hospital, Lanzhou, China.

Period circadian protein homolog 1 (PER1) is an important component of the biorhythm molecular oscillation system and plays an important part in the development and progression of mammalian cancer. However, the correlations of PER1 with prognosis and tumor-infiltrating lymphocytes in ovarian cancer (OV) remain unclear. The Oncomine and TIMER databases were used to examine the expression of PER1 in OV. Kaplan-Meier Plotter and PrognoScan were used to evaluate the relationship between PER1 and prognosis. Kaplan-Meier Plotter was used to analyze the relationships between PER1 and clinicopathological features of OV patients. The relationship between PER1 expression and immune infiltration in OV was investigated using the TIMER database and CIBERSORT algorithm. The STRING database was used to analyze PER1-related protein functional groups, the GeneMANIA online tool was used to analyze gene groups with similar functions to those of PER1, and Network Analyst was used to identify transcription factors that regulate PER1. The correlation between PER1 and immunoinvasion of OV was analyzed using TIMER. Finally, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect PER1 expression. PER1 was differentially expressed in different cancer tissues, and its expression in various OV subtypes was lower than that in normal ovarian tissue. OV patients with low PER1 expression had a reduced overall survival rate. Decreased PER1 expression in stage 1 and stage 1+2 OV patients was related to poor prognosis, while increased PER1 expression in stage 3+4 patients and TP53 mutation were related to poor overall survival and progression-free survival. We identified eight genes whose expression was strongly correlated with that of PER1, as well as four transcription factors that regulate PER1. In OV, PER1 expression levels were positively correlated with infiltration levels of cells including neutrophils, regulatory T cells, and M2 macrophages, and closely related to a variety of immune markers. Reduced expression of PER1 was significantly associated with poor overall survival. These findings suggest that PER1 could be used as a prognostic biomarker to determine prognosis and immune infiltration in OV patients.
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http://dx.doi.org/10.3389/fgene.2021.697471DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8248530PMC
June 2021

A cellular nitric oxide sensor based on porous hollow fiber with flow-through configuration.

Biosens Bioelectron 2021 Jun 16;191:113442. Epub 2021 Jun 16.

College of Pharmacy, Hangzhou Normal University, China; Key Laboratory of Elemene Class Anti-Cancer Medicines, Hangzhou Normal University, China. Electronic address:

Nitric oxide plays important transmission and regulation roles in the human body, but its in-vitro concentration is extremely low with a short half-life. In this work, we developed a three-dimensional 'flow-through' configuration based on polysulfone hollow fiber (PHF) for efficient detection of cell released NO. The PHF served as the substrate for cell culture as well as the base layer of the working electrode. The carbon nanotubes-gold nanoparticles (CNT-AuNPs) composites uniformly wrapped around the PHF as the sensing layer. The CNT provided a large specific surface area, which allowed uniform distribution and high loading of AuNPs, thus enhancing the electrocatalytic activity synergistically. Compared with the conventional flow-by configuration, such configuration resulted in a higher surface area per unit volume and enhanced NO molecule capture efficiency. The CNT-AuNPs PHF sensor showed a low detection limit (91 nM), high stability, selectivity, and biocompatibility. We utilized it for real-time in-situ detection of NO released by human lung cancer cell H1299 under drug stimulation. Furthermore, owing to the unique PHF structure, we performed long-term monitoring of NO release under the treatment of Lipopolysaccharide, Nitroglycerin and Aminoguanidine, which helps to understand the kinetic process of cellular drug response.
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http://dx.doi.org/10.1016/j.bios.2021.113442DOI Listing
June 2021

Copper chloride complexes with substituted 4'-phenyl-terpyridine ligands: synthesis, characterization, antiproliferative activities and DNA interactions.

Dalton Trans 2021 Jun 25;50(23):8243-8257. Epub 2021 May 25.

School of Chemistry and Chemical Engineering, Guangxi University, 530004 Nanning, Guangxi, People's Republic of China.

Eleven copper chloride coordination compounds (1-11) with 4'-(4'-substituted-phenyl)-2,2':6',2''-terpyridine ligands bearing hydrogen (L), cyano (L), p-hydroxyl (L), m-hydroxyl (L), o-hydroxyl (L), methoxyl (L), iodo (L), bromo (L), chloro (L), fluoro (L) or methylsulfonyl (L) were prepared and characterized by IR spectroscopy, elemental analysis and single crystal X-ray diffraction. Antiproliferative activities against tumor cells were investigated and DNA interactions were studied by circular dichroism spectroscopy and molecular modeling methods. In vitro data demonstrate that all the compounds exhibit higher antiproliferative activities as compared to cisplatin against five human carcinoma cell lines: A549, Bel-7402, Eca-109, HeLa and MCF-7. Compound 6 with methoxyl shows the best anti-proliferation activity. Spectrophotometric results reveal the strong affinity of the compounds for binding with DNA as intercalators and induce DNA conformational transitions. The results of molecular docking studies show that the compounds interact with DNA through π-π stacking, van der Waals forces, hydrophobic interactions and hydrogen bonds. The binding energies between compound 11 and three macromolecules, including DNA duplex, oligonucleotide and DNA-Topo I complex, are the lowest. The binding stability of compounds containing hydroxyl, methoxy and methylsulfonyl groups with biological macromolecules mainly relies on the hydrogen bonds. The ability of a compound to form hydrogen bonds can promote its binding to biological targets, thereby exhibiting high antiproliferative activity.
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http://dx.doi.org/10.1039/d0dt03989fDOI Listing
June 2021

Engineering spatial-organized cardiac organoids for developmental toxicity testing.

Stem Cell Reports 2021 May 22;16(5):1228-1244. Epub 2021 Apr 22.

Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA; BioInspired Syracuse Institute for Material and Living Systems, Syracuse, NY, USA. Electronic address:

Emerging technologies in stem cell engineering have produced sophisticated organoid platforms by controlling stem cell fate via biomaterial instructive cues. By micropatterning and differentiating human induced pluripotent stem cells (hiPSCs), we have engineered spatially organized cardiac organoids with contracting cardiomyocytes in the center surrounded by stromal cells distributed along the pattern perimeter. We investigated how geometric confinement directed the structural morphology and contractile functions of the cardiac organoids and tailored the pattern geometry to optimize organoid production. Using modern data-mining techniques, we found that pattern sizes significantly affected contraction functions, particularly in the parameters related to contraction duration and diastolic functions. We applied cardiac organoids generated from 600 μm diameter circles as a developmental toxicity screening assay and quantified the embryotoxic potential of nine pharmaceutical compounds. These cardiac organoids have potential use as an in vitro platform for studying organoid structure-function relationships, developmental processes, and drug-induced cardiac developmental toxicity.
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http://dx.doi.org/10.1016/j.stemcr.2021.03.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8185451PMC
May 2021

Effects of high-flux hemodialysis combined with levocarnitine on vascular calcification, microinflammation, hepcidin, and malnutrition of elderly patients on maintenance hemodialysis.

Ann Palliat Med 2021 Mar;10(3):3286-3298

Department of Nephrology, The Affiliated Xiaolan Hospital of Southern Medical University, Zhongshan, China.

Background: This study was to investigate the effect of high-flux hemodialysis (HD) combined with levocarnitine on vascular calcification, microinflammation, hepcidin, and malnutrition in elderly patients on maintenance HD (MHD).

Methods: 75 MHD elderly patients admitted to hospital between 1st September 2017 and 31st August 2019 were selected as the study subjects. They were randomly divided by digital table into three groups: low-flux group (n=25), high-flux group (n=25) and joint group (n=25). In the low-flux group, dialyzer had an ultrafiltration coefficient 12 mL/(h·mmHg) and effective surface area of 1.4 m2 compared with 59 mL/(h·mmHg) and 1.8 m2 in the high-flux group. After treatment, the calcification of blood vessels was examined by lateral X-ray, pelvic plain film and bilateral positive position. For patients in all groups, the concentrations of parathyroid hormone (PTH) and β 2-microglobulin (β 2-MG) in serum were measured by automatic chemiluminescence; levels of interleukin-6, C-reactive protein (CRP), and tumor necrosis factor alpha (TNF-α) were measured by ELISA before and after treatment; and the level of hepcidin was measured by ELISA. Before and 12 weeks after the treatment, the nutritional status of the patients was evaluated by modified quantitative subjective global assessment (MQSGA), hemoglobin (Hb) and red blood cell count (RBC). Complications in the three groups were recorded, including nausea, chest pain, hypotension, hypertension, pruritus, dry heat, muscle spasm, arrhythmia, and restless legs.

Results: Vascular calcification in the joint group was better than the low-flux and high-flux groups (P<0.05). After treatment, the serum PTH and β 2-mg concentrations in the joint group were lower than those in the other two groups (P<0.05), and the levels of IL-6, CRP, TNF-α and hepcidin in the joint group were significantly lower than those before treatment (P<0.05). After treatment, the MQSGA scores in the joint group were lower than those in the low-flux and high-flux groups (P<0.05), and Hb and RBC were higher (P<0.05).

Conclusions: The combination of high-flux HD and levocarnitine in elderly patients on MHD can increase the clearance of medium and large molecular toxins, effectively correct malnutrition, alleviate microinflammation, delay the progress of vascular calcification, and is safe.
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http://dx.doi.org/10.21037/apm-21-66DOI Listing
March 2021

Isolated Pea Resistant Starch Substrates with Different Structural Features Modulate the Production of Short-Chain Fatty Acids and Metabolism of Microbiota in Anaerobic Fermentation In Vitro.

J Agric Food Chem 2021 May 12;69(18):5392-5404. Epub 2021 Apr 12.

College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, Shaanxi 710062, China.

Resistant starches (RSs) with different structural features were isolated from both native and pullulanase-debranched and acid-hydrolyzed pea starches. Their microscopic changes, short-chain fatty acids (SCFA) composition, microbiota communities, and structural characteristics of the corresponding fermenta residues by the end of 24 h of the in vitro fermentation period were investigated. The microbial fermentation clearly caused numerous cracks and erosion on the RS granule surface. In comparison to the positive control, significantly higher levels of butyrate, propionate, and total SCFA were produced after 24 h of in vitro fecal fermentation when resistant starches were used as substrates. The RS substrates with different structural characteristics enabled varying growth of spp., spp., and spp. The discrepancy in microbiota communities associated with the differences in SCFA from the fermentation of RS with different structural features would be critical toward the rational design of foods containing resistant starch with targeted health benefits.
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http://dx.doi.org/10.1021/acs.jafc.0c08197DOI Listing
May 2021

Comparative investigation of early-onset gastric cancer.

Oncol Lett 2021 May 13;21(5):374. Epub 2021 Mar 13.

The Second Clinical Medical College, Lanzhou University Second Hospital, Lanzhou University, Lanzhou, Gansu 730030, P.R. China.

Early-onset gastric cancer (EOGC) is a serious social burden. For patients with EOGC, typically considered as those aged <45 years, the underlying cause of the disease remains unclear. In addition, several misunderstandings of EOGC remain in clinical practice. Upon diagnosis, numerous patients with EOGC are already at an advanced stage (stage IV) of the disease and are unable to benefit from treatment. Moreover, several conclusions and data obtained from different EOGC studies appear to be to contradictory. The literature indicates that the incidence of EOGC is gradually rising, and that EOGC differs from traditional and familial gastric cancer in terms of clinicopathological characteristics. Patients with EOGC typically exhibit low survival rates, poor prognosis, rapid disease progression, a low degree of differentiation (signet-ring cell tumors are common) and rapid lymph node and distant metastasis, among other characteristics. The molecular genetic mechanisms of EOGC are also significantly different from those of traditional gastric cancer. An improved definition of EOCG may provide a reference for clinical diagnosis and treatment, and clear guidelines may serve as a basis for more accurate diagnosis and the development of effective treatment strategies.
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http://dx.doi.org/10.3892/ol.2021.12635DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7988708PMC
May 2021

Sulfur-Resistant Ceria-Based Low-Temperature SCR Catalysts with the Non-bulk Electronic States of Ceria.

Environ Sci Technol 2021 04 16;55(8):5435-5441. Epub 2021 Mar 16.

Department of Environmental Science & Engineering, Fudan University, 2005 Songhu Road, Shanghai 200438, China.

Although ceria-based catalysts serve as an appealing alternative to traditional VO-based catalysts for selective catalytic reduction (SCR) of NO with NH, the inevitable deactivation caused by SO at low temperatures severely hampers the ceria-based catalysts to efficiently control NO emissions from SO-containing stack gases. Here, we rationally design a strong sulfur-resistant ceria-based catalyst by tuning the electronic structures of ceria highly dispersed on acidic MoO surfaces. By using Ce L-edge X-ray absorption near edge structure spectra in conjunction with various surface and bulk structural characterizations, we report that the sulfur resistance of the catalysts is closely associated with the electronic states of ceria, particularly expressed by the Ce/Ce ratio related to the size of the ceria particles. As the Ce/Ce ratio increases up to or over 50%, corresponding to CeO/MoO( %, ≤ 2.1) with the particle size of approximately 4 nm or less, the non-bulk electronic states of ceria appear, where the catalysts start to show strong sulfur resistance. This work could provide a new strategy for designing sulfur-resistant ceria-based SCR catalysts for controlling NO emissions at low temperatures.
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http://dx.doi.org/10.1021/acs.est.0c08736DOI Listing
April 2021

Stimuli-responsive biomaterials for cardiac tissue engineering and dynamic mechanobiology.

APL Bioeng 2021 Mar 2;5(1):011506. Epub 2021 Mar 2.

Since the term "smart materials" was put forward in the 1980s, stimuli-responsive biomaterials have been used as powerful tools in tissue engineering, mechanobiology, and clinical applications. For the purpose of myocardial repair and regeneration, stimuli-responsive biomaterials are employed to fabricate hydrogels and nanoparticles for targeted delivery of therapeutic drugs and cells, which have been proved to alleviate disease progression and enhance tissue regeneration. By reproducing the sophisticated and dynamic microenvironment of the native heart, stimuli-responsive biomaterials have also been used to engineer dynamic culture systems to understand how cardiac cells and tissues respond to progressive changes in extracellular microenvironments, enabling the investigation of dynamic cell mechanobiology. Here, we provide an overview of stimuli-responsive biomaterials used in cardiovascular research applications, with a specific focus on cardiac tissue engineering and dynamic cell mechanobiology. We also discuss how these smart materials can be utilized to mimic the dynamic microenvironment during heart development, which might provide an opportunity to reveal the fundamental mechanisms of cardiomyogenesis and cardiac maturation.
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http://dx.doi.org/10.1063/5.0025378DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7929620PMC
March 2021

Adventitial Progenitor Cells of Human Great Saphenous Vein Enhance the Resolution of Venous Thrombosis via Neovascularization.

Stem Cells Int 2021 23;2021:8816763. Epub 2021 Feb 23.

Department of Vascular Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China.

Background: Vascular adventitia contains progenitor cells and is shown to participate in vascular remolding. Progenitor cells are recruited into the venous thrombi in mice to promote neovascularization. We hypothesized that the adventitial progenitor cells of human great saphenous vein (HGSV-AdPC) enhance the resolution of venous thrombosis via neovascularization.

Methods: Human great saphenous vein (HGSV) was harvested from the patients with great saphenous vein varicose and sectioned for immunohistochemistry, or minced for progenitor cell primary culture, or placed in sodium dodecyl sulfate solution for decellularization. Human venous thrombi were collected from patients with great saphenous vein varicose and superficial thrombophlebitis. Infrarenal abdominal aorta of New Zealand white rabbits was replaced with interposing decellularized vessel, and the patency of the grafts was confirmed by ultrasonic examination. Animal venous thrombi in the left infrarenal vena cava of mice were produced with Prolene suture ligation and ophthalmic force clipping of this portion. After HGSVs were digested by collagenase, the CD34CD117 HGSV-AdPC were isolated on FACS system, labelled with CM-Dil, and transplanted into the adventitia of infrarenal vena cava of nude mice. The percentage of thrombus organization area to the thrombus area was calculated as the organization rate. The thrombus cell, endothelial cells, and macrophages in the thrombi were counted in sections. Cell smears and frozen sections of human saphenous veins and venous thrombi were labeled with Sca1, CD34, CD117, Flk1, CD31, and F4/80 antibodies. The CD34CD117 HGSV-AdPC were cultured in endothelial growth medium with vascular endothelial growth factor (VEGF) to induce endothelial cell differentiation and analyzed with real time-PCR, Western blotting, and tube formation assays.

Results: Immunohistochemical staining showed that the CD34CD117 cells were located within the adventitia of HGSVs, and many CD34 and CD117 cells have emerged in the human venous thrombi. The number of progenitor cells within the marginal area of 7 days mice thrombi was shown to be Sca1 ≈21%, CD34 ≈12%, CD117 ≈9%, and Flk1 ≈5%. Many CD34adventitial progenitor cells have migrated into the decellularized vessels. FACS showed that the number of CD34CD117 HGSV-AdPC in primary cultured cells as 1.2 ± 0.07%. After CD34CD117HGSV-AdPC were transplanted into the adventitia of nude mice vena cava with venous thrombi, the organization rate, nucleate cell count, endothelial cells, and macrophage cells of thrombi were shown to be significantly increased. The transplanted CD34CD117 HGSV-AdPC at the adventitia have crossed the vein wall, entered the venous thrombi, and differentiated into endothelial cells. The CD34CD117 HGSV-AdPC in the culture medium in the presence of VEGF-promoted gene and protein expression of endothelial cell markers and induced tube formation.

Conclusions: HGSV-AdPC could cross the vein wall and migrate from the adventitia into the venous thrombi. Increased HGSV-AdPC in the adventitia has enhanced the resolution of venous thrombi via differentiating into endothelial cells of neovascularization.
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http://dx.doi.org/10.1155/2021/8816763DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7926266PMC
February 2021

Combined transcriptome and proteome analyses reveal differences in the longissimus dorsi muscle between Kazakh cattle and Xinjiang brown cattle.

Anim Biosci 2021 Feb 15. Epub 2021 Feb 15.

College of Animal Science and Technology, Shihezi University, Shihezi, 832000, China.

Objective: With the rapid development of proteomics sequencing and RNA sequencing technology, multi-omics analysis has become a current research hotspot. Our previous study indicated that Xinjiang brown cattle have better meat quality than Kazakh cattle. In this study, Xinjiang brown cattle and Kazakh cattle were used as the research objects.

Methods: Proteome sequencing and RNA sequencing technology were used to analyze the proteome and transcriptome of the longissimus dorsi muscle of the two breeds of adult steers (n=3).

Results: In this project, 22677 transcripts and 1874 proteins were identified through quantitative analysis of the transcriptome and proteome. By comparing the identified transcriptome and proteome, we found that 1737 genes were identified at both the transcriptome and proteome levels. The results of the study revealed 12 differentially expressed genes and proteins: TNNI1, CRYAB, CSRP3, PTER, MYBPH, GSTM3, MYL3, NID2, DPYSL2, GOT1, REEP5 and ASPA. We performed functional enrichment of these differentially expressed genes and proteins. The KEGG results showed that these differentially expressed genes and proteins are enriched in the fatty acid degradation and histidine metabolism signaling pathways. We performed PRM verification of the differentially expressed proteins, and the PRM results were consistent with the sequencing results.

Conclusion: Our study provided and identified the differentially expressed genes and proteins. In addition, identifying functional genes and proteins with important breeding value will provide genetic resources and technical support for the breeding and industrialization of new genetically modified beef cattle breeds.
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http://dx.doi.org/10.5713/ab.20.0751DOI Listing
February 2021

Giant Intraparenchymal Meningioma in a Female Child: Case Report and Literature Review.

Cancer Manag Res 2021 25;13:1989-1997. Epub 2021 Feb 25.

Department of Neurosurgery, Henan University People's Hospital, Henan Provincial People's Hospital, Zhengzhou, People's Republic of China.

Background: Intraparenchymal meningiomas without dural attachment are extremely rare, especially in female children. To our knowledge, fibrous intraparenchymal meningioma located in the temporal lobe has never been reported in female children. The significance in the differential diagnosis of lesions in the temporal lobe should be emphasized.

Case Presentation: A 12-year-old girl was admitted to our hospital, complaining of recurrent generalized seizures for 2 months. Magnetic resonance imaging demonstrated a solid lesion located in the temporal lobe. The lesion underwent gross total resection. Histopathological examination indicated that the lesion was a fibrous meningioma. Postoperative rehabilitation was uneventful.

Conclusion: This case report presents an extremely unusual intraparenchymal fibrous meningioma of the temporal lobe with peritumoral edema and reviewed 21 intraparenchymal meningioma cases in children and to discuss the clinical presentation and treatment, differential diagnosis, and radiological features.
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http://dx.doi.org/10.2147/CMAR.S294224DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7920497PMC
February 2021

Selective degradation of the estrogen receptor in the treatment of cancers.

J Steroid Biochem Mol Biol 2021 May 18;209:105848. Epub 2021 Feb 18.

Institute of Materia Medica, Hangzhou Medical College, 310013 Hangzhou, Zhejiang, China. Electronic address:

Estrogen receptor subtype α (ERα) plays key roles in breast cancers, and has been a target for endocrine therapy for a long time. Unfortunately, long-term treatment by Aromatase Inhibitors (AIs) or Selective Estrogen Receptor Modulators (SERMs) could cause drug resistance and also would increase the risk for uterine cancer. Therefore, novel anti-breast cancer drugs based on different mechanisms of action have received significant attention, especially through the strategies of selective degradation of ER. In this article, the latest research progress of selective targeting ER for degradation, including Selective ER Downregulators (SERDs), Proteolysis Targeting Chimaeras (PROTACs) and other techniques, was reviewed, and the applications and problems to be solved were prospected.
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http://dx.doi.org/10.1016/j.jsbmb.2021.105848DOI Listing
May 2021

Fast Stereolithography Printing of Large-Scale Biocompatible Hydrogel Models.

Adv Healthc Mater 2021 05 15;10(10):e2002103. Epub 2021 Feb 15.

Department of Biomedical Engineering, University at Buffalo, The State University of New York, Buffalo, NY, 14260, USA.

Large size cell-laden hydrogel models hold great promise for tissue repair and organ transplantation, but their fabrication using 3D bioprinting is limited by the slow printing speed that can affect the part quality and the biological activity of the encapsulated cells. Here a fast hydrogel stereolithography printing (FLOAT) method is presented that allows the creation of a centimeter-sized, multiscale solid hydrogel model within minutes. Through precisely controlling the photopolymerization condition, low suction force-driven, high-velocity flow of the hydrogel prepolymer is established that supports the continuous replenishment of the prepolymer solution below the curing part and the nonstop part growth. The rapid printing of centimeter-sized hydrogel models using FLOAT is shown to significantly reduce the part deformation and cellular injury caused by the prolonged exposure to the environmental stresses in conventional 3D printing methods. Embedded vessel networks fabricated through multiscale printing allows media perfusion needed to maintain the high cellular viability and metabolic functions in the deep core of the large-sized models. The endothelialization of this vessel network allows the establishment of barrier functions. Together, these studies demonstrate a rapid 3D hydrogel printing method and represent a first step toward the fabrication of large-sized engineered tissue models.
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http://dx.doi.org/10.1002/adhm.202002103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8212355PMC
May 2021

Application of micronised acellular dermal matrix for primary premature ejaculation: A preliminary study.

Andrologia 2021 May 14;53(4):e13994. Epub 2021 Feb 14.

Department of Urology, Shandong Provincial Hospital, Shandong, China.

This study aimed to explore the efficacy of injection of micronised acellular dermal matrix (MADM) particles for treating primary premature ejaculation. This study was a prospective single-arm clinical trial. Thirty patients who met the surgical indications were enrolled. MADM particles, mixed in platelet-rich plasma, were injected into Buck's fascia to spread over the dorsal penile nerve, suppress the influx of nerve impulses and, thus, reduce penis sensitivity. We evaluated the changes according to intravaginal ejaculation latency time using a stopwatch and a premature ejaculation diagnostic tool. Meanwhile, we also recorded sexual partner satisfaction and adverse events. All patients recovered well after surgery with no complications such as infections or allergies. The mean intravaginal ejaculation latency time before surgery was 0.72 ± 0.28 min, compared with 2.41 ± 0.54 min, 2.64 ± 0.41 min, 2.79 ± 0.25 min and 2.89 ± 0.35 min at, respectively, 4, 8, 16 and 20 weeks after surgery. The premature ejaculation diagnostic values and sexual partner satisfaction had significantly improved after treatment. Injection of MADM particles is an effective, safe and simple method for treating premature ejaculation.
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http://dx.doi.org/10.1111/and.13994DOI Listing
May 2021

Kinase SnRK1.1 Regulates nitrate channel SLAH3 Engaged in Nitrate-Dependent Alleviation of Ammonium Toxicity.

Plant Physiol 2021 Feb 9. Epub 2021 Feb 9.

Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.

Nitrate (NO3-) and ammonium (NH4+) are major inorganic nitrogen (N) supplies for plants, but NH4+ as the sole or dominant N source causes growth inhibition in many plants, known as ammonium toxicity. Small amounts of NO3- can significantly mitigate ammonium toxicity, and the anion channel SLAC1 homologue 3 (SLAH3) is involved in this process, but the mechanistic detail of how SLAH3 regulates nitrate-dependent alleviation of ammonium toxicity is still largely unknown. In this study, we identified SnRK1.1, a central regulator involved in energy homeostasis and various stress responses, as a SLAH3-interactor in Arabidopsis (Arabidopsis thaliana). Our results suggest that SNF1-related protein kinase 1 (SnRK1.1) functions as a negative regulator of SLAH3. Kinase assays indicate SnRK1.1 strongly phosphorylates the C-terminal of SLAH3 at the site S601. Under high-NH4+/low-pH condition, phospho-mimetic and phospho-dead mutations in SLAH3 S601 result in barely rescued phenotypes and fully complemented phenotypes in slah3. Furthermore, SnRK1.1 migrates from cytoplasm to nucleus under high-NH4+/low-pH conditions. The translocation of SnRK1.1 from cytosol to nucleus under high-ammonium stress releases the inhibition on SLAH3, which allows SLAH3-mediated NO3- efflux leading to alleviation of high-NH4+/low-pH stress. Our study reveals that the C-terminal phosphorylation also plays important role in SLAH3 regulation and provides additional insights into nitrate-dependent alleviation of ammonium toxicity in plants.
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http://dx.doi.org/10.1093/plphys/kiab057DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8154061PMC
February 2021

Biomaterial-guided stem cell organoid engineering for modeling development and diseases.

Acta Biomater 2021 Jan 22. Epub 2021 Jan 22.

Department of Biomedical and Chemical Engineering, Syracuse University, NY, United States; BioInspired Syracuse Institute for Material and Living Systems, NY, United States. Electronic address:

Organoids are miniature models of organs to recapitulate spatiotemporal cellular organization and tissue functionality. The production of organoids has revolutionized the field of developmental biology, providing the possibility to study and guide human development and diseases in a dish. More recently, novel biomaterial-based culture systems demonstrated the feasibility and versatility to engineer and produce the organoids in a consistent and reproducible manner. By engineering proper tissue microenvironment, functional organoids have been able to exhibit spatial-distinct tissue patterning and morphogenesis. This review focuses on enabling technologies in the field of organoid engineering, including the control of biochemical and biophysical cues via hydrogels, as well as size and geometry control via microwell and microfabrication techniques. In addition, this review discusses the enhancement of organoid systems for therapeutic applications using biofabrication and organoid-on-chip platforms, which facilitate the assembly of complex organoid systems for in vitro modeling of development and diseases.
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http://dx.doi.org/10.1016/j.actbio.2021.01.026DOI Listing
January 2021

Preparation of rutin-loaded microparticles by debranched lentil starch-based wall materials: Structure, morphology and in vitro release behavior.

Int J Biol Macromol 2021 Mar 20;173:293-306. Epub 2021 Jan 20.

College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, Shaanxi 710062, China.

Different treatments of autoclaving, pullulanase debranching and/or ultrasound were applied to prepare debranched lentil starch (DBLS). Their fine structures can affect the retrogradation patterns of DBLSs, which consequently could affect their potential use as delivery carrier of sensitive bioactive compounds. An attempt was made to use these DBLSs as wall materials to encapsulate rutin, aiming to improve the bioaccessibility, meanwhile to enhance the aqueous solubility and stability of rutin molecules. Their encapsulation efficiency, structural characteristics, thermal stability, morphological features, antioxidant activity and in vitro release behavior under simulated upper gastrointestinal tract environment were evaluated. The results suggested that rutin was dispersed in the DBLS polymer matrix, showing the amorphous nature that further authenticates the encapsulation and entrapment of rutin. The structural analyses of microparticles revealed that rutin could interacted with DBLS biopolymer chains by hydrogen bonds, making the starch molecular chains less susceptible to interact with themselves for reordering. The encapsulation efficiency was found to be in an opposite trend with those values obtained for relative crystallinity, melting enthalpy, degree of order/double helices of DBLS wall materials before encapsulation. The release rate results indicated that DBLS carrier with lower M, DP and higher molecular order was beneficial for the slower release of rutin encapsulated in the microparticles.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.01.122DOI Listing
March 2021

Structural rearrangement of native and processed pea starches following simulated digestion in vitro and fermentation characteristics of their resistant starch residues using human fecal inoculum.

Int J Biol Macromol 2021 Mar 17;172:490-502. Epub 2021 Jan 17.

College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an, Shaanxi 710062, China.

Pea starches, in both native (NPS) and retrograded-autoclaved forms (RAPS), were subjected to simulated gastrointestinal (GI) digestion in vitro, their multi-scale structural characteristics, morphological features, molecular distribution and thermal properties were characterized. A gradual increase in the short-/long-range crystallinity, melting enthalpy of gelatinization on increasing digestion time was observed for both the native and retrograded-autoclaved pea starch samples based on the X-ray diffraction, Fourier-transform infrared spectra, solid-state CNMR and differential scanning calorimetry measurements. It was especially noticed that the growth rate of crystallinity and double helices, as well as the decrease in M values were evidently greater for RAPS than for NPS. To investigate how different molecular fine structure of pea starch substrate affects the gut microbiota shifts and dynamic short-chain fatty acid profile, their resistant starch residues obtained from both native and retrograded-autoclaved pea starch after 8 h of simulated GI tract digestion was used as the fermentation substrate. The levels of acetate, propionate and butyrate gradually increased with the increasing fermentation time for NPS and RAPS. In comparison to the blank control (i.e., the group without the addition of carbohydrate), the fermented NPS and RAPS obviously resulted in an increased abundance of Firmicutes and Bacteroidetes, accompanied by a decrease in Proteobacteria, Actinobacteria and Verrucomicrobia. Both NPS and RAPS promoted different shifts in the microbial community at the genus level, with an increase in the abundance of Bacteroides, Megamonas and Bifidobacterium, as well as a reduction in the abundance of Fusobacterium, Faecalibacterium and Lachnoclostridium in comparison to the blank control samples.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.01.092DOI Listing
March 2021

Associations between insecurity and stress among Chinese university students: The mediating effects of hope and self-efficacy.

J Affect Disord 2021 02 15;281:447-453. Epub 2020 Dec 15.

School of Psychology, Center for Studies of Social Psychology, Central China Normal University, China. Electronic address:

Background: In the context of the pandemic, exploration on the association between insecurity and stress among university students is limited. The current study aims to investigate the parallel mediation role of hope and self-efficacy in the relationship between insecurity and stress among university students during the COVID-19 pandemic.

Methods: We employed a cross-sectional research design in a university by distributing questionnaires online. 5286 participants were recruited (mean age = 19.65; SD = 1.13). Items were from the Security Questionnaire, Depression Anxiety and Stress Scale-21, and the Positive Psychology Capital (Psycap) Questionnaire (PPQ). Parallel mediation analysis was performed using PROCESS macro in SPSS.

Results: The results indicate that insecurity predicted students' stress positively and that students with high-level perceived insecurity are more likely to perceive stress. Moreover, hope and self-efficacy mediated the relationship between insecurity and stress, indicating that hope and self-efficacy could buffer the negative effects of insecurity on stress.

Limitations: This study examines the mediating model between insecurity and stress among Chinese university students. The generalizability of the findings in other regions remains to be explored. Additionally, the roles of other positive self-beliefs including optimism and resilience in relieving stress can be further explored in future research.

Conclusions: This research provides direct evidence of insecurity effects on stress among university students, enriching relevant theories in the field of stress. Moreover, this research suggests that enhancing positive self-beliefs such as hope, and self-efficacy helps to relieve students' stress during COVID-19.
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http://dx.doi.org/10.1016/j.jad.2020.12.047DOI Listing
February 2021

Release of fluorine and chlorine during increase of phosphate rock grade by calcination and digestion.

Environ Pollut 2021 Feb 15;270:116321. Epub 2020 Dec 15.

College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang, 330022, China.

A series of experiments for calcination and subsequent digestion to increase the grade of phosphate rock were performed. Fluorine and chlorine released by calcination and digestion were investigated. The forms of both elements were studied by sequential chemical extraction. The grades of raw and calcined phosphate rocks, and their phosphorus concentrates were confirmed according to the value of PO%. The results showed that fluorine and chlorine in phosphate rock mainly existed in carbonate-bound and residual forms. The grade of phosphate rock can be well increased by calcination and subsequent digestion. By digestion at the optimal condition of 2.5:1 for liquid-solid ratio, 60 °C for digestion temperature and 50 min for digestion time, the phosphorus concentrates digested from the calcined phosphate rock of 1000 °C reached the highest grade (PO% = 33.24%). By calcination, the released fluorine was mainly HF at a low temperature and SiF at a high temperature, with fluorine release amount of 1.61 × 10-3.82 × 10 g/t at 900-1100 °C. Cl, HCl and Cl were mainly released at 200-500 °C, less than 800 °C and more than 800 °C, which release amount were 9.40 × 10-2.54 × 10 g/t, 2.10 × 10-1.53 × 10 g/t and 2.24 × 10-5.61 × 10 g/t, respectively. By digestion with water for the calcined phosphate rock of 900-1100 °C, the concentrations of fluorine and chlorine in effluent were respectively 77.2-160 mg/L and 7.99-19.6 mg/L. It can be concluded that fluorine and chlorine released by calcination for phosphate rock contribute greatly to atmospheric acid rain and equipment corrosion; by digestion, the discharge of fluorine seriously exceeds the standard and may cause greater pollution to the water body.
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http://dx.doi.org/10.1016/j.envpol.2020.116321DOI Listing
February 2021

Human appropriation of net primary production estimates in the Xinjiang grasslands.

PLoS One 2020 2;15(12):e0242478. Epub 2020 Dec 2.

Key Laboratory of Restoration Ecology for Cold Regions Laboratory in Qinghai, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai, China.

The human appropriation of net primary production (HANPP) was developed to estimate the intensity of human activities in natural ecosystems, which is still unclear in the Xinjiang grasslands. Using the Biome-Biogeochemical Cycle (Biome-BGC) grazing model in combination with field data, we assessed the HANPP and explored its spatiotemporal patterns in the Xinjiang grasslands. Our results showed that (1) the HANPP increased from 38 g C/m2/yr in 1979 to 88 g C/m2/yr in 2012, with an average annual increase of 1.47%. The HANPP was 80 g C/m2/yr, which represented 51% of the potential net primary production (NPPpot), and the HANPP efficiency was 70% in this region. (2) The areas with high HANPP values mainly occurred in northern Xinjiang and northwest of the Tianshan Mountains, while areas with low HANPP values mainly occurred in southern Xinjiang and southwest of the Tianshan Mountains. (3) Interannual variations in HANPP and NPPpot were significantly positively correlated (P<0.01). Interannual variations in HANPP efficiency and grazing intensity were negatively correlated (P<0.01). These results can help identify the complex impacts of human activities on grassland ecosystems and provide basic data for grassland management.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0242478PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7710112PMC
January 2021

g-CN Modified by -Tetrahydroxyphenylchlorin for Photocatalytic Hydrogen Evolution Under Visible/Near-Infrared Light.

Authors:
Yanfei Liu Zhen Ma

Front Chem 2020 6;8:605343. Epub 2020 Nov 6.

Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai, China.

A new photocatalyst denoted as mTHPC/pCN was prepared by modifying protonated graphitic carbon nitride (pCN) by -tetrahydroxyphenylchlorin (mTHPC). Relevant samples were characterized via various methods including zeta potential measurements, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, N adsorption-desorption, transmission electron microscopy, ultraviolet-visible-near-infrared spectroscopy, electrochemical impedance spectroscopy, photocurrent response measurements, electron spin resonance spectroscopy, and phosphorescence spectroscopy. Compared with pCN, mTHPC/pCN shows enhanced absorption in the visible and near-infrared regions and thus higher photocatalytic activity in hydrogen evolution. A possible mechanism for mTHPC/pCN is proposed.
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http://dx.doi.org/10.3389/fchem.2020.605343DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7677346PMC
November 2020

Evidence of the Berezinskii-Kosterlitz-Thouless phase in a frustrated magnet.

Nat Commun 2020 Nov 6;11(1):5631. Epub 2020 Nov 6.

Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing, 100872, China.

The Berezinskii-Kosterlitz-Thouless (BKT) mechanism, building upon proliferation of topological defects in 2D systems, is the first example of phase transition beyond the Landau-Ginzburg paradigm of symmetry breaking. Such a topological phase transition has long been sought yet undiscovered directly in magnetic materials. Here, we pin down two transitions that bound a BKT phase in an ideal 2D frustrated magnet TmMgGaO, via nuclear magnetic resonance under in-plane magnetic fields, which do not disturb the low-energy electronic states and allow BKT fluctuations to be detected sensitively. Moreover, by applying out-of-plane fields, we find a critical scaling behavior of the magnetic susceptibility expected for the BKT transition. The experimental findings can be explained by quantum Monte Carlo simulations applied on an accurate triangular-lattice Ising model of the compound which hosts a BKT phase. These results provide a concrete example for the BKT phase and offer an ideal platform for future investigations on the BKT physics in magnetic materials.
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http://dx.doi.org/10.1038/s41467-020-19380-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7648753PMC
November 2020

The preliminary experience of methylene blue assisted laparoscopy in the treatment of renal parapelvic cysts.

Sci Rep 2020 10 30;10(1):18757. Epub 2020 Oct 30.

Department of Urology, Tianjin Third Central Hospital, NO.83 Jintang Road, Hedong District, Tianjin, 300170, China.

Renal cyst is a common disease in humans and laparoscopic renal cyst decortication is the gold standard for treatment. However, specialized surgical skills are required for the treatment of renal parapelvic cysts. In this study, we describe an improved laparoscopic method for the treatment of renal parapelvic cysts involving the use of continuous infusion of methylene blue. Sixteen patients with renal parapelvic cyst were enrolled in this study. All patients underwent retrograde ureteral catheterization, with continuous perfusion of the renal pelvis using a solution of 0.2% methylene blue and saline, during laparoscopic decortication of the parapelvic cyst. In one patient, the cyst communicated with the renal collection system which was injured, but this was immediately repaired intraoperatively. All operations were successful, and none was converted to open surgery. There were no occurrences of persistent urinary fistula, bleeding, or other complications postoperatively. All patients were followed-up for 3-24 months, and results of postoperative imaging investigations revealed that all of our patients experienced either complete recovery or a greater than 50% decrease in size of the cysts. Our study demonstrates that methylene blue-assisted laparoscopic treatment is a safe, effective and practical method for the treatment of renal parapelvic cysts.
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http://dx.doi.org/10.1038/s41598-020-76006-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599209PMC
October 2020

Classification of auditory attention focuses during speech perception.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:3074-3077

Passive brain-computer interfaces (BCIs) covertly decode the cognitive and emotional states of users by using neurophysiological signals. An important issue for passive BCIs is to monitor the attentional state of the brain. Previous studies mainly focus on the classification of attention levels, i.e. high vs. low levels, but few has investigated the classification of attention focuses during speech perception. In this paper, we tried to use electroencephalography (EEG) to recognize the subject's attention focuses on either call sign or number when listening to a short sentence. Fifteen subjects participated in this study, and they were required to focus on either call sign or number for each listening task. A new algorithm was proposed to classify the EEG patterns of different attention focuses, which combined common spatial pattern (CSP), short-time Fourier transformation (STFT) and discriminative canonical pattern matching (DCPM). As a result, the accuracy reached an average of 78.38% with a peak of 93.93% for single trial classification. The results of this study demonstrate the proposed algorithm is effective to classify the auditory attention focuses during speech perception.
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http://dx.doi.org/10.1109/EMBC44109.2020.9176300DOI Listing
July 2020

Multiscale structural changes and retrogradation effects of addition of sodium alginate to fermented and native wheat starch.

Int J Biol Macromol 2020 Nov 19;163:2286-2294. Epub 2020 Sep 19.

Hebei Jinshahe Flour and Noodle Group Co., Ltd., Hebei Cereal Food Processing Technology Innovation Center, Hebei 054100, China.

This work investigated the changes in multi-scale structure and retrogradation properties of native wheat starches (NS) modified by sodium alginate (AG) with and without fermentation. AG adhered on the surface of NS granules and fermentation promoted the adhesions. Compared with the addition of AG alone, dual modification by fermentation and AG together showed a greater effect to increase the weight-average molecular weight and reduce the relative crystallinity and double helix degree of NS. Small angle X-ray diffraction results showed a significant increase in amorphous region with dual modification compared with AG alone. Additionally, dual modification greatly slowed the increase of relative crystallinity and the enthalpy (ΔH) of NS paste during storage. The results of this study suggest that dual modification is a more effective approach to modify structures and properties of wheat starch than single AG treatment, and suggest its potential industrial application in starch-based foods.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.09.094DOI Listing
November 2020

Fabrication and Microstructure of ZnO/HA Composite with In Situ Formation of Second-Phase ZnO.

Materials (Basel) 2020 Sep 7;13(18). Epub 2020 Sep 7.

School of Materials Science and Engineering, Jiamusi University, Jiamusi 154007, China.

Nanometer hydroxyapatite (n-HA) powders were synthesized by the chemical precipitation method, and a novel ZnO/HA composite, which consisted of second-phase particles with different sizes and distributions, was successfully fabricated. ZnO/HA composites were prepared by using powder sintering with different Zn contents and a prefabrication pressure of 150 MPa. Microstructure and local chemical composition were analyzed by a scanning electron microscope (SEM) and energy-dispersive spectrometer (EDS), respectively. The phase composition and distribution of the composite were determined with electron back-scattered diffraction (EBSD) and an X-ray diffractometer (XRD), respectively. The experimental results of the XRD showed that the chemical precipitation method was a simple and efficient method to obtain high-purity n-HA powders. When the sintering temperature was lower than 1250 °C, the thermal stability of HA was not affected by the Zn in the sintering process. Due to sintering in an air atmosphere, the oxidation reaction of Zn took place in three stages, and ZnO as the second phase had two different sizes and distributions in the composites. The compressive strength of ZnO/HA composites, of which the highest was up to 332 MPa when the Zn content was 20%, was significantly improved compared with pure HA. The improvement in mechanical properties was mainly due to the distribution of fine ZnO particles among HA grains, which hindered the HA grain boundary migration and refinement of HA grains. As grain refinement increased the area of the grain boundary inside the material, both the grain boundary and second phase hindered crack development in different ways.
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http://dx.doi.org/10.3390/ma13183948DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7558110PMC
September 2020
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