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1.
Foods ; 12(21)2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37959036

ABSTRACT

The mulberry leaf is a botanical resource that possesses a substantial quantity of protein. In this study, alcalase hydrolysis conditions of mulberry leaf protein were optimized using the response surface method. The results showed that the optimum conditions were as follows: substrate protein concentration was 0.5% (w/v), enzymatic hydrolysis temperature was 53.0 °C, enzymatic hydrolysis time was 4.7 h, enzyme amount was 17,800 U/g, and pH was 10.5. Then mulberry leaf peptides were separated by ultrafiltration according to molecular weight. Peptides (<3 kDa) were screened and subsequently identified using LC-MS/MS after the evaluation of α-glucosidase inhibition across various fractions. Three novel potential bioactive peptides RWPFFAFM (1101.32 Da), AAGRLPGY (803.91 Da), and VVRDFHNA (957.04 Da) with the lowest average docking energy were screened for molecular dynamics simulation to examine their binding stability with enzymes in a 37 °C simulated human environment. Finally, they were prepared by solid phase synthesis for in vitro verification. The former two peptides exhibited better IC50 values (1.299 mM and 1.319 mM, respectively). These results suggest that the α-glucosidase inhibitory peptides from mulberry leaf protein are potential functional foods or drugs for diabetes treatment, but further in vivo studies are needed to identify the bioavailability and toxicity.

2.
Article in English | MEDLINE | ID: mdl-37971467

ABSTRACT

Objective: To investigate the protective effect of Illicium verum extract on the vascularization of osteoporotic fracture in rats, and to elucidate its potential mechanism. Methods: The osteoporotic fracture model was established in ovariectomized rats. Rats were infused with 0.05 ml/kg extract in the stomach every morning. Eighteen rats are then divided into control group, model group, and Illicium verum extract group with 6 rats in each group. To observe the therapeutic effect of Illicium verum extract on osteoporotic rats. Femoral bone mineral density and elastic segment end-point load were evaluated by dual-energy x-ray absorptiometry and three-point bending test. Hematoxylin-eosin staining was used to measure the number and area of callus blood vessels. The serum levels of VEGF and NO were detected by ELISA. Moreover, the expressions of NOX2, NOX4, NRF2, p-PI3K, CyclinD1, VEGF, HIF1α, and eNOS in HUVEC were detected by Western blot. CCK8 and wound healing assay were used to detect the proliferation and migration of HUVEC. Then, the ability of HUVEC to form blood vessels was detected by tube formation assay. Results: Firstly, control group showed the normal pathomorphology and density of femoral bone, and model group showed significantly decreased bone density and consistent with bone microstructure degeneration, destruction, thinning, and fracture of bone trabecular structure vs control group, and illicium verum extract significantly increased femoral density and maximum load, increased the number and area of callus blood vessels and increased VEGF and NO levels in serum vs model group. Then, Illicium verum extract promoted the expression of NRF2, p-PI3K, CyclinD1, VEGF, HIF1α, and eNOS protein in HUVEC, inhibited the expression of NOX2 and NOX4, and enhanced the cell proliferation, migration, and angiogenesis. However, the effect was reversed by the overexpression of NRF2 and the treatment with LY294002. Conclusion: Illicium verum extract protects the vascularization of the osteoporotic fracture model in rats.

3.
Heliyon ; 9(5): e16248, 2023 May.
Article in English | MEDLINE | ID: mdl-37229157

ABSTRACT

Objectives: This study aimed to evaluate the potential clinical application of an infiltrant with different etchants as pit and fissure sealants and to compare them with a conventional resin-based sealant. Materials and methods: Seventy-five molars were randomly divided into three groups (n = 25): phosphoric acid etchant + conventional resin-based sealant (Group A); 15% hydrochloric acid etchant + infiltrant (Group B); phosphoric acid etchant + infiltrant (Group C). Fifteen teeth in each group were subjected to pit and fissure sealing procedures. After 500 thermocycling and methylene blue dye penetration, ten specimens were sectioned and the pencentages of dye penetration were measured under a stereomicroscope. Another five teeth in each group were sectioned and the microgaps between materials and enamel surface were measured using electron microscope scanning. Ten teeth in each group were used to measure shear bond strength and the failure mode was analyzed. Results: The results showed that infiltrant exhibited significantly less microleakage and microgap than resin-based sealant, no matter which echant was used. Although there was no significant difference betweern the three groups, infiltrant applied with 15% hydrochloric acid etching showed higher shear bond strength than resin-based sealant etching with 35% phosphoric acid. Conclusions: The infiltrant has significant advantages in reducing the degree of microleakage and microgap. Moreover, the infiltrant could achieve the same bonding strength as conventional resin-based sealant. Although, manufacturers do not currently recommend the infiltrant for fissure sealing, the potential clinical application would be an off-label use.Clinical relevance This report provides a theoretical basis for the potential clinical application of the infiltrant as a pit and fissure sealant, and provides a new perspective for selecting pit and fissure sealants.

4.
Front Oncol ; 12: 894043, 2022.
Article in English | MEDLINE | ID: mdl-35898871

ABSTRACT

Background: Forkhead box S1 (FOXS1) is a member of the forkhead box (FOX) transcriptional factor superfamily. The biological roles and underlying regulatory mechanism of FOXS1 in CRC remain unclear. Methods: Bioinformatics analysis, Western blotting, real-time PCR, and immunohistochemistry (IHC) were used to detect the expression FOXS1 in CRC. MTT assay, transwell assay, human umbilical vein endothelial cell tube formation assay, and chicken chorioallantoic membrane assay were performed to investigate the effects of FOXS1 on proliferation, invasion, and angiogenesis. Additionally, tumor formation assay and orthotopic implantation assay were used to investigate the effects of FOXS1 on tumor growth and metastasis in vivo. Furthermore, gene set enrichment analysis (GSEA) was used to analyze the correlation between FOXS1 and EMT or angiogenesis. The correlation between FOXS1 and CXCL8 expression was analyzed in clinical CRC samples using IHC. Results: The results showed that FOXS1 expression was upregulated in CRC tissues compared with adjacent normal intestine tissues. A high FOXS1 expression is positively correlated with poor survival. FOXS1 promoted the malignant behavior of CRC cancer cells in vitro, including proliferation, invasion, and angiogenesis. In addition, FOXS1 promoted tumor growth and metastasis in nude mice. Mechanistically, FOXS1 upregulated the expression of C-X-C motif chemokine ligand 8 (CXCL8) at the transcriptional level. Knockdown of CXCL8 blocked FOXS1 induced the enhancement of the EMT and angiogenesis. GSEAs in public CRC datasets revealed strong correlations between FOXS1 expression and EMT marker and angiogenesis markers. IHC showed that FOXS1 expression was positively correlated with CXCL8 expression and CD31 expression in clinical CRC samples. Conclusion: The results suggest that FOXS1 promotes angiogenesis and metastasis by upregulating CXCL8 in CRC. Interference with the FOXS1/CXCL8 axis may serve as a potential therapeutic target for the treatment of metastatic CRC.

5.
J Immunol Res ; 2022: 5600190, 2022.
Article in English | MEDLINE | ID: mdl-35733917

ABSTRACT

Osteoarthritis (OA) is thought to be the most prevalent chronic joint disease. The incidence of OA is rising because of the ageing population and the epidemic of obesity. This research was designed for the identification of novel diagnostic biomarkers for OA and analyzing the possible association between critical genes and infiltrated immune cells. 10 OA samples from patients with spinal OA and 10 normal samples were collected. GSE55235 and GSE55457 datasets including human OA and normal samples were downloaded from the GEO datasets. Differentially expressed genes (DEGs) were identified between 20 OA and 20 controls. SVM-RFE analysis and LASSO regression model were carried out to screen possible markers. The compositional patterns of the 22 types of immune cell fraction in OA were determined by the use of CIBERSORT. The expression level of the biomarkers in OA was examined by the use of RT-PCR. In this study, an overall 44 DEGs were identified: 18 genes were remarkably upregulated and 26 genes were distinctly downregulated. KEGG pathway analyses revealed that pathways were significantly enriched including IL-17 signal path, rheumatoid arthritis, TNF signal path, and lipid and atherosclerosis. Based on the results of machine learning, we identified APOLD1 and EPYC as critical diagnostic genes in OA, which were further confirmed using ROC assays. Immune cell infiltration analysis revealed that APOLD1 was correlated with mastocytes stimulated, NK cells resting, T cells CD4 memory resting, DCs stimulated, T cells gamma delta, macrophages M0, NK cells stimulated, and mastocytes resting. Moreover, we found that EPYC was correlated with mastocytes stimulated, NK cells resting, T cells CD4 memory resting, DCs stimulated, T cells gamma delta, macrophages M0, NK cells stimulated, and mastocytes resting. Overall, our findings might provide some novel clue for the exploration of novel markers for OA diagnosis. The critical genes and their associations with immune infiltration may offer new insight into understanding OA developments.


Subject(s)
Computational Biology , Osteoarthritis , Biomarkers/metabolism , Computational Biology/methods , Gene Expression Profiling/methods , Gene Regulatory Networks , Humans , Machine Learning , Osteoarthritis/diagnosis , Osteoarthritis/genetics , Osteoarthritis/metabolism
6.
J Exp Clin Cancer Res ; 40(1): 304, 2021 Sep 28.
Article in English | MEDLINE | ID: mdl-34583750

ABSTRACT

BACKGROUND: Tumor-associated macrophages (TAMs) are key regulators of the complex interplay between cancer and the immune microenvironment. Tumor cell-derived spondin 2 (SPON2) is an extracellular matrix glycoprotein that has complicated roles in recruitment of macrophages and neutrophils during inflammation. Overexpression of SPON2 has been shown to promote tumor cell migration in colorectal cancer (CRC). However, the mechanism by which SPON2 regulates the accumulation of TAMs in the tumor microenvironment (TME) of CRC is unknown. METHODS: Immunohistochemistry was used to examine SPON2 expression in clinical CRC tissues. In vitro migration assays, transendothelial migration assays (iTEM), and cell adhesion assays were used to investigate the effects of SPON2 on monocyte/macrophage migration. Subcutaneous tumor formation and orthotopic implantation assays were performed in C57 BL/6 mice to confirm the effects of SPON2 on TAM infiltration in tumors. RESULTS: SPON2 expression is positively correlated with M2-TAM infiltration in clinical CRC tumors and poor prognosis of CRC patients. In addition, SPON2 promotes cytoskeletal remodeling and transendothelial migration of monocytes by activating integrin ß1/PYK2 axis. SPON2 may indirectly induce M2-polarization through upregulating cytokines including IL10, CCL2 and CSF1 expression in tumor cells. Blocking M2 polarization and Macrophage depletion inhibited the SPON2-induced tumors growth and invasion. Furthermore, blocking the SPON2/integrin ß1/PYK2 axis impairs the transendothelial migration of monocytes and cancer-promoting functions of TAMs in vivo. CONCLUSIONS: Our findings demonstrate that SPON2-driven M2-TAM infiltration plays an important role during CRC tumor growth and metastasis. SPON2 may be a valuable biomarker guiding the use of macrophage-targeting strategies and a potential therapeutic target in advanced CRC.


Subject(s)
Biomarkers, Tumor/metabolism , Colorectal Neoplasms/pathology , Extracellular Matrix Proteins/metabolism , Focal Adhesion Kinase 2/metabolism , Gene Expression Regulation, Neoplastic , Liver Neoplasms/secondary , Neoplasm Proteins/metabolism , Tumor-Associated Macrophages/immunology , Animals , Apoptosis , Biomarkers, Tumor/genetics , Cell Proliferation , Colorectal Neoplasms/immunology , Colorectal Neoplasms/metabolism , Extracellular Matrix Proteins/genetics , Female , Focal Adhesion Kinase 2/genetics , Humans , Liver Neoplasms/immunology , Liver Neoplasms/metabolism , Mice , Mice, Inbred C57BL , Neoplasm Proteins/genetics , Prognosis , Survival Rate , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
7.
BMC Geriatr ; 21(1): 506, 2021 09 25.
Article in English | MEDLINE | ID: mdl-34563130

ABSTRACT

BACKGROUND: Whether an association between alcohol consumption and dental caries exists is still unclear. Chinese Baijiu is the most common alcohol consumed by middle-aged and elderly Chinese individuals. This study aimed to assess the relationship between alcohol consumption (Chinese Baijiu) and dental caries in Guangdong Province, southern China. METHODS: A cross-sectional study was conducted in Guangdong Province using a multistage, stratified, equal-sized, random sampling strategy. In total, 576 individuals aged 55-74 were recruited to fill out a questionnaire through face-to-face and one-on-one interviews and to undergo a series of dental examinations with a Community Periodontal Index (CPI) probe. According to the standard for clinical dentition examination of the WHO 2013 criteria, the presence of dental caries was determined by the DFT/DFRoot (decayed-filled tooth/root) index. The ratios of males to females and urban people to countrymen were both 1:1. Then, the chi-square test and rank-sum tests were used to compare the differences in caries between subgroups, and multivariate logistic regression analyses, as well as negative binomial regression analyses, were executed to identify the potential relationship between alcohol consumption and caries. RESULTS: The prevalence of crown caries was 79.17% with a DFT index of 3.19, while that of root caries was 61.28% with a DFRoot index of 2.08. The prevalence and mean tooth of crown caries of females were higher than those of males. The prevalence and mean DFRoot of root caries in rural areas were higher than those in urban areas. The results of the multivariate logistic regression analysis and negative binomial regression analysis showed that there was a statistically significant negative correlation between the consumption frequency of Chinese Baijiu and caries (often vs. never/rarely, crown caries: odds ratio (OR) = 0.54, 95% confidence interval (CI): 0.26-1.13, P = 0.103, incidence rate ratio (IRR) = 0.63, 95% CI: 0.44-0.92, P = 0.015; root caries: OR = 0.47, 95% CI: 0.24-0.93, P = 0.030, IRR = 0.52, 95% CI: 0.32-0.54, P = 0.008). CONCLUSIONS: Within the limitations of this study, frequent consumption of Chinese Baijiu was a protective factor for caries in middle-aged and elderly people in Guangdong Province. However, considering the harm of alcohol to one's general health, it is recommended to drink moderately and avoid alcohol abuse.


Subject(s)
Dental Caries , Aged , China/epidemiology , Cross-Sectional Studies , DMF Index , Dental Caries/diagnosis , Dental Caries/epidemiology , Female , Humans , Male , Middle Aged , Prevalence
8.
Phys Rev E ; 103(6-1): 062607, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34271742

ABSTRACT

Janus particles with different patch sizes, confined to two dimensions, generate a series of patterns of interest to the field of nanoscience. Here we observe reverse melting, where for some densities the system melts under cooling. For a broad range of hydrophobic patch sizes (60^{∘}<θ_{0}<90^{∘}), a reentrant transition from solid to liquid and then to an ordered phase emerges as temperature (T) decreases due to the formation of rhombus chains at low T. This reentrant phase has pseudo long-range orientational order but short-range translational order, similar to a hexatic phase. Our work provides guidelines to study the melting and assembly of Janus particles in two dimensions, as well as mechanisms to generate phases with specific symmetry.

9.
Oral Health Prev Dent ; 18(1): 731-740, 2020 Sep 04.
Article in English | MEDLINE | ID: mdl-32895656

ABSTRACT

PURPOSE: To assess the current prevalence of caries, gingival bleeding, calculus, and fluorosis and to determine the risk factors for caries in permanent teeth of 12-year-old students in Guangdong Province, China. MATERIALS AND METHODS: A cross-sectional survey was carried out among 1920 12-year-old students in Guangdong Province. All participants were required to undergo an oral health examination. Information concerning the subjects' family background, dietary habits, and relevant oral health behaviour were collected in a structured questionnaire. Chi-squared tests, Wilcoxon rank-sum tests, and the logistic regression model were used in the statistical analysis. RESULTS: The prevalence rates of caries in permanent teeth, gingival bleeding, calculus, and fluorosis were 43.07%, 40.57%, 43.75%, and 5.05%, respectively; the average decayed, missing, and filled teeth (DMFT) index was 1.06±1.721. Residence (odds ratios [OR] rural=1.798, 95% CI: 1.485-2.177), sex (OR female=1.352, 95% CI: 1.121-1.631), paternal education level (OR >9 years=0.755, 95% CI: 0.608-0.936), presence of calculus (OR yes=1.279, 95% CI: 1.057-1.548), and frequency of consumption of sugary snacks (OR frequently=1.418, 95% CI: 1.064-1.890) were statistically significantly associated with the risk of permanent teeth caries. CONCLUSION: Oral health in 12-year-olds in Guangdong Province remains to be improved. Rural residence, female sex, the presence of calculus, and frequent consumption of sugary snacks could increase the risk of caries. The paternal educational level was negatively associated with the risk of caries, whereas we found no association between the maternal educational level and the risk of caries in this population.


Subject(s)
Dental Caries , Oral Health , Child , China , Cross-Sectional Studies , DMF Index , Female , Humans , Prevalence , Risk Factors , Students
10.
Zhongguo Gu Shang ; 33(6): 576-84, 2020 Jun 25.
Article in Chinese | MEDLINE | ID: mdl-32573167

ABSTRACT

OBJECTIVE: To systematically assess the efficacy of anterior cervical corpectomy and fusion (ACCF) versus posterior laminoplasty (LAMP) for cervical ossification of posterior longitudinal ligament (OPLL). METHODS: PubMed and EMBASE, Cochrane Library, CBM, CNKI, Wanfang and VIP were collected from 7 databases of ACCF, LAMP from 1970 to May 2018. According to the criteria, the articles were included and independently screened by two authors. The quality of the articles was assessed by using the MINORS scale (methodological index for non randomized studies). After extracting the data from the article, the JOA score, cervical curvature, operation time, bleeding volume, excellent and good rate, recovery rate, adverse events and secondary surgery were analyzed by using Review Manager 5.3 software. RESULTS: Finally, a total of 22 articles with 1 678 patients were included in this Meta-analysis, with 810 patients in ACCF group and 868 patients in LAMP group. Meta analysis results showed that the ACCF group had higher postoperative JOA scores[MD=0.63, 95%CI(0.05, 1.20), P= 0.03], higher excellent rate [OR=1.85, 95%CI (1.14, 3.02), P=0.01] and higher recovery rate [OR=11.90, 95%CI (5.75, 18.05), P=0.000 1]. But the LAMP group has a shorter operative time [MD=52.19, 95%CI (29.36, 75.03), P<0.000 01], less complications [OR=1.56, 95%CI (1.03, 2.35), P=0.04] and less reoperations [OR=3.73, 95%CI (1.62, 8.57), P=0.002]. There was no significant different in postoperative lordosis [MD=3.15, 95%CI(-0.14, 6.43), P=0.06] and blood loss[SMD= 0.26, 95%CI(-0.05, 0.57), P=0.10] between two groups. CONCLUSION: The recovery of functionof ACCF group was better, but operation time, complications and reoperations of LAMP group were all better than ACCF group. There was no difference in postoperative lordosis and intraoperative blood loss between two groups. However, there are some limitations in this study. Therefore, higher quality and larger sample size clinical studies are needed to further verify.


Subject(s)
Laminoplasty , Ossification of Posterior Longitudinal Ligament , Spinal Fusion , Vertebroplasty , Calcium , Cervical Vertebrae , Decompression, Surgical , Humans , Treatment Outcome
11.
Zhongguo Zhen Jiu ; 40(2): 147-51, 2020 Feb 12.
Article in Chinese | MEDLINE | ID: mdl-32100499

ABSTRACT

OBJECTIVE: To observe the auxiliary analgesic effect of wrist-ankle acupuncture on patients undergoing transforaminal endoscope surgery. METHODS: A total of 64 patients with lumbar disc herniation who underwent percutaneous lateral transforaminal endoscope surgery were randomly divided into an observation group and a control group, 32 cases in each group. The patients in the control group were treated with injection of 1% lidocaine for routine local infiltration anesthesia. The patients in the observation group were treated with wrist-ankle acupuncture at lower 5 area and lower 6 area for 30 min, 5 min before routine local infiltration anesthesia; immediately, 15 min, 30 min after insertion the left-right technique, up-down technique, and rotation technique were applied for six times, respectively. The mean arterial pressure (MAP), heart rate (HR), blood oxygen saturation (SpO2) and pain visual analogue scale (VAS) were compared between the two groups at the time points of intraoperative puncture (T1), circular saw grinding (T2), and placement of working channel (T3). The intention of reoperation was recorded immediately after operation and 24 h after operation. The expectation and treatment credibility scale (ETCS) was used to evaluate the relationship between patients' expectation and efficacy 5 min before operation and immediately after operation. RESULTS: At T2 and T3 during the operation, the MAP and HR in the obserrvation group were lower than those in the control group, while SpO2 was higher than that in the control group (P<0.05). At T1, there was no significant difference of MAP, HR and SpO2 between the two groups (P>0.05). At T2, the peak VAS and average VAS in the observation group were lower than those in the control group (P<0.05), but there was no significant difference at T1 and T3 (P>0.05). The intention of reoperation in the observation group was higher than that in the control group both immediately after operation and 24 h after operation (P<0.05). In the observation group, the scores of each item in ETCS immediately after operation were higher than those 5 min before operation (P<0.05), while in the control group there was no significant difference between immediately after operation and 5 min before operation (P>0.05). The scores of ETCS1, ETCS2 and ETCS3 immediately after operation in the observation group were higher than those in the control group (P<0.05). CONCLUSION: The wrist-ankle acupuncture has positive auxiliary analgesic effect on lumbago during transforaminal endoscope surgery, and strengthens the patients' confidence on the operation effect.


Subject(s)
Acupuncture Analgesia , Ankle , Endoscopy , Wrist , Analgesics , Humans , Spine/surgery
12.
World Neurosurg ; 136: e83-e89, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31866456

ABSTRACT

BACKGROUND: Percutaneous endoscopic lumbar discectomy has been widely used to treat lumbar disc herniation; its advantages are less trauma, faster recovery, lower costs, and higher percentage of patient satisfaction compared with open surgery. Treatment of lumbar spinal stenosis with percutaneous full-endoscopic surgery is still challenging, especially for elderly patients with multiple comorbidities and complex pathologic factors. The aim of this study was to introduce percutaneous full-endoscopic lumbar foraminoplasty and decompression using a visualization reamer in elderly patients with lateral recess and foraminal stenosis and evaluate efficacy and safety. METHODS: This retrospective review comprised 65 consecutive elderly patients (30 men and 35 women) with lateral recess and foraminal stenosis who underwent percutaneous full-endoscopic lumbar foraminoplasty and discectomy from January 2017 to September 2017. Visual analog scale and Oswestry Disability Index were used to evaluate pain relief and neurologic improvement. RESULTS: Mean patient age was 71.58 years (range, 65-89 years). Mean follow-up period was 16.12 months (range, 12-20 months). Mean operative time was 98.59 minutes per level (range, 55-120 minutes). Mean intraoperative perspective frequency was 3.21 times (range, 2-6 times). Mean hospital stay after the procedure was 2.18 days (range, 1-4 days). Back and leg visual analog scale and Oswestry Disability Index scores at all time points in the postoperative period were significantly lower than preoperatively (P < 0.01). At final follow-up, modified MacNab criteria were rated as follows: excellent, 47 patients (72.31%); good, 12 patients (16.92%); fair, 3 patients (4.62%); and poor, 4 patients (6.15%). Therefore, excellent or good results were obtained in 89.23% of patients. CONCLUSIONS: Percutaneous full-endoscopic lumbar foraminoplasty and discectomy using a visualization reamer is an effective and safe treatment for elderly patients with lumbar lateral recess and foraminal stenosis. It improves safety and efficiency of decompression and reduces intraoperative fluoroscopy.


Subject(s)
Decompression, Surgical/methods , Lumbar Vertebrae/surgery , Spinal Stenosis/surgery , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Retrospective Studies , Treatment Outcome
13.
Phys Rev Lett ; 122(5): 058001, 2019 Feb 08.
Article in English | MEDLINE | ID: mdl-30821995

ABSTRACT

Rare earths, which are fundamental components of modern technologies, are often extracted from aqueous solutions using surfactants at oil-water interfaces. Heavier lanthanides are more easily extracted, even though all lanthanides are chemically very similar. Using x-ray fluorescence measurements and theoretical arguments, we show that there is a sharp bulk-concentration-dependent transition in the interfacial adsorption of cations from aqueous solutions containing Er^{3+} or Nd^{3+} in contact with a floating monolayer. The threshold bulk concentration of erbium (Z=68) is an order of magnitude lower than that of neodymium (Z=60), and erbium is preferentially adsorbed when the solution contains both ions. This implies that elemental selectivity during separation originates at the surfactant interface. Electrostatic effects arising from the interface dielectric mismatch, ionic correlations, and sizes of the ions explain the sharp adsorption curve and selectivity.

14.
Phys Rev Lett ; 120(24): 248101, 2018 Jun 15.
Article in English | MEDLINE | ID: mdl-29956983

ABSTRACT

Dynamics of hydration water is essential for the function of biomacromolecules. Previous studies have demonstrated that water molecules exhibit subdiffusion on the surface of biomacromolecules; yet the microscopic mechanism remains vague. Here, by performing neutron scattering, molecular dynamics simulations, and analytic modeling on hydrated perdeuterated protein powders, we found water molecules jump randomly between trapping sites on protein surfaces, whose waiting times obey a broad distribution, resulting in subdiffusion. Moreover, the subdiffusive exponent gradually increases with observation time towards normal diffusion due to a many-body volume-exclusion effect.


Subject(s)
Proteins/chemistry , Water/chemistry , Cytochrome P-450 Enzyme System/chemistry , Diffusion , Green Fluorescent Proteins/chemistry , Models, Chemical , Molecular Dynamics Simulation , Neutron Diffraction
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