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1.
Nutr Res ; 125: 79-90, 2024 May.
Article En | MEDLINE | ID: mdl-38552503

Patients with colorectal cancer (CRC) are at high risk of frailty, leading to reduced quality of life and survival. Diet is associated with frailty in the elderly through regulating inflammation. Thus, we hypothesized that dietary inflammatory potential (as assessed by dietary inflammatory index [DII]) might be associated with frailty in patients with CRC through regulating inflammatory biomarkers. A total of 231 patients with CRC were included in this cross-sectional study. Dietary intake was evaluated by 3-day, 24-hour dietary recalls, and frailty status was assessed in accordance with the Fried frailty criteria. Plasma inflammatory cytokines were determined in 126 blood samples. A total of 67 patients (29.0%) were frail, with significantly higher DII scores than nonfrail patients, accompanied with significantly increased interleukin-6 (IL-6) and decreased interleukin-10 (IL-10) concentrations. Each 1-point increase of DII was related to a 25.0% increased risk of frailty. IL-6 was positively correlated with frailty and DII, whereas IL-10 was negatively correlated. After adjusting for age, sex, body mass index, education level, smoking status, and energy, mediation analysis revealed that the association between DII and frailty was significantly mediated by IL-6 (average causal mediation effect [ACME], 0.052; 95% confidence interval, 0.020-0.087; P = .002) and IL-10 (ACME, 0.025; 95% confidence interval, 0.004-0.063; P = .016). The ρ values for the sensitivity measure at which estimated ACMEs were zero were 0.3 and -0.2 for IL-6 and IL-10, respectively. Therefore, a pro-inflammatory diet was associated with frailty in patients with CRC possibly in part by affecting circulating IL-6 and IL-10 concentrations.


Colorectal Neoplasms , Diet , Frailty , Inflammation , Interleukin-10 , Interleukin-6 , Humans , Colorectal Neoplasms/blood , Cross-Sectional Studies , Male , Female , Frailty/blood , Inflammation/blood , Aged , Interleukin-6/blood , Interleukin-10/blood , Middle Aged , Biomarkers/blood
2.
Mol Inform ; 42(6): e2200223, 2023 Jun.
Article En | MEDLINE | ID: mdl-37040091

The present work was devoted to explore the quantitative structure-property relationships for gas-to-ionic liquid partition coefficients (log KILA ). A series of linear models were first established for the representative dataset (IL01). The optimal model was a four-parameter equation (1Ed) consisting of two electrostatic potential-based descriptors ( Σ V s , i n d - ${{\rm { \Sigma }}{V}_{s,ind}^{-}}$ and Vs,max ), one 2D matrix-based descriptor (J_D/Dt) and dipole moment (µ). All of the four descriptors introduced in the model can find the corresponding parameters, directly or indirectly, from Abraham's linear solvation energy relationship (LSER) or its theoretical alternatives, which endows the model good interpretability. Gaussian process was utilized to build the nonlinear model. Systematical validations, including 5-fold cross-validation for the training set, the validation for test set, as well as a more rigorous Monte Carlo cross-validation were performed to verify the reliability of the constructed models. Applicability domain of the model was evaluated, and the Williams plot revealed that the model can be used to predict the log KILA values of structurally diverse solutes. The other 13 datasets were also processed in the same way, and all of the linear models with expressions similar to equation 1Ed were obtained. These models, whether linear of nonlinear, represent satisfactory statistical results, which confirms the universality of the method adopted in this study in QSPR modeling of gas-to-IL partition.


Ionic Liquids , Quantitative Structure-Activity Relationship , Reproducibility of Results , Linear Models , Monte Carlo Method
3.
Adv Healthc Mater ; 12(17): e2202770, 2023 07.
Article En | MEDLINE | ID: mdl-36864695

Dressing change is a significant and inevitable process during wound healing. Possible secondary damage caused through dressing removal may impose a great threat on wound recovery, thus resulting in healing delays and ultimately a higher cost of hospitalization. Hence, a non-contact refreshable dressing with an ease of operation is of great desire, especially for chronic wounds where a long-term and repeated dressing change would be performed. Herein, an all-light-operated hydrogel dressing that would achieve a fast and remote-controllable dressing change (30 s for gelation/4 min for dissolution upon light irradiation) for chronic wounds is presented. In a diabetic murine model, substantially improved wound healing within 2-3 weeks is observed due to attenuated secondary damage during repeated dressing changes. Moreover, a promising facilitation of the healing processes of epithelialization, collagen deposition, cell proliferation, and inflammatory regulation is also detected, representing a synergistic effect of the photo-responsive hydrogel dressing for therapeutic efficiency.


Diabetes Mellitus , Hydrogels , Mice , Animals , Hydrogels/pharmacology , Hydrogels/therapeutic use , Wound Healing , Collagen , Bandages , Diabetes Mellitus/drug therapy
4.
ACS Appl Mater Interfaces ; 15(9): 11496-11506, 2023 Mar 08.
Article En | MEDLINE | ID: mdl-36821340

Inventions of materials to achieve biocompatibility, bioadhesion, and easy manufacturing are the urgent demand for promoting wound healing in clinical treatment. Hyaluronic acid (HA) is probably the ideal candidate for current dressing materials due to its well-known biocompatibility. However, the unavoidable problem for HA dressings is their inherent low adhesiveness to wounds, which severely impairs their treatment efficacy, especially during body movement. Here, we report a one-pot facile fabrication of hybrid double-network polydopamine-HA (PDA-HA) hydrogel with significantly enhanced adhesiveness compared to the HA hydrogel. Besides the easy manufacturing and promoted effectiveness, the PDA-HA hydrogel could be vacuum-dried to form a patch, further benefitting from the convenience for storage and distribution. When applied on the wound, the PDA-HA patch quickly rehydrated by absorbing exudate and stuck tightly to the wound. The applied PDA-HA patches keep the wounds covered for more than 7 days against strenuous exercise. Thus, mouse full-thickness wounds treated with the PDA-HA patches exhibited increased healing rates, where epithelization was finished within 14 days. Moreover, the hydrogel dressing exhibited promoting effects on vascularization and cell proliferation/migration. Together with the easy manufacturing procedure, good adhesion/adaptation, and promotion of wound healing, the PDA-HA patch holds great potential for future clinical translation.


Hydrogels , Wound Healing , Mice , Animals , Hydrogels/pharmacology , Bandages , Hyaluronic Acid/pharmacology , Antioxidants/pharmacology , Anti-Bacterial Agents/pharmacology
5.
JMIR Mhealth Uhealth ; 10(3): e30571, 2022 03 30.
Article En | MEDLINE | ID: mdl-35353055

BACKGROUND: China has the largest number of patients with type 2 diabetes mellitus (T2DM) in the world. However, owing to insufficient knowledge of self-management in patients with diabetes, blood glucose (BG) control is poor. Most diabetes-related self-management applications fail to bring significant benefits to patients with T2DM because of the low use rate and difficult operation. OBJECTIVE: This study aims to examine the effectiveness of the combination of the self-designed web-based T2DM management software TangPlan and WeChat on fasting BG (FBG), glycated hemoglobin (HbA1c), body weight, blood pressure (BP), and lipid profiles in patients with T2DM over a 6-month period. METHODS: Participants were recruited and randomized into the TangPlan and WeChat or control groups. Participants in the control group received usual care, whereas the TangPlan and WeChat participants received self-management guidance with the help of TangPlan and WeChat from health care professionals, including BG self-monitoring; healthy eating; active physical exercise; increasing medication compliance; and health education during follow-ups, lectures, or web-based communication. They were also asked to record and send self-management data to the health care professionals via WeChat to obtain timely and effective guidance on diabetes self-management. RESULTS: In this study, 76.9% (120/156) of participants completed the 6-month follow-up visit. After the intervention, FBG (mean 6.51, SD 1.66 mmol/L; P=.048), HbA1c (mean 6.87%, SD 1.11%; P<.001), body weight (mean 66.50, SD 9.51 kg; P=.006), systolic BP (mean 127.03, SD 8.00 mm Hg; P=.005), diastolic BP (mean 75.25, SD 5.88 mm Hg; P=.03), serum low-density lipoprotein cholesterol (mean 2.50, SD 0.61 mmol/L; P=.006), and total cholesterol (mean 4.01, SD 0.83 mmol/L; P=.02) in the TangPlan and WeChat group were all significantly lower, whereas serum high-density lipoprotein cholesterol (mean 1.20, SD 0.25 mmol/L; P=.01) was remarkably higher than in those in the control group. Compared with the baseline data, significance was found in the mean change in FBG (95% CI -0.83 to -0.20; P=.002), HbA1c (95% CI -1.92 to -1.28; P<.001), body weight (95% CI -3.13 to -1.68; P<.001), BMI (95% CI -1.10 to -0.60; P<.001), systolic BP (95% CI -7.37 to -3.94; P<.001), diastolic BP (95% CI -4.52 to -2.33; P<.001), triglycerides (95% CI -0.16 to -0.03; P=.004), serum low-density lipoprotein cholesterol (95% CI -0.54 to -0.30; P<.001), and total cholesterol (95% CI -0.60 to -0.34; P<.001) in the TangPlan and WeChat group but not in the control group (P=.08-.88). CONCLUSIONS: Compared with usual care for patients with T2DM, the combination of TangPlan and WeChat was effective in improving glycemic control (decrease in HbA1c and BG levels) and serum lipid profiles as well as reducing body weight in patients with T2DM after 6 months. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000028843; https://tinyurl.com/559kuve6.


Diabetes Mellitus, Type 2 , Self-Management , Diabetes Mellitus, Type 2/therapy , Exercise , Glycated Hemoglobin/analysis , Humans , Internet
7.
Orthop Surg ; 13(6): 1863-1869, 2021 Aug.
Article En | MEDLINE | ID: mdl-34351066

OBJECTIVE: To evaluate the midterm outcomes and the capsular healing in patients who had interportal capsulotomy versus periportal capsulotomy of hip arthroscopy. METHODS: Retrospectively reviewed 33 patients with labral tear received hip arthroscopy, with an average age of 41 (27-67) years, including 13 cases of Cam deformity and three cases of Pincer deformity. All patients had positive sign of flexion adduction internal rotation or flexion abduction external rotation. With MRI and radiographic (CT, X plain) imageological examination. MRI showed that all patients had labral tear. Radiographic finding (CT, X plain) showed the pathological changes of acetabular and femoral neck osteophyte. One group with 23 patients were treated with periportal capsulotomy. Another group with 10 patients were treated with interportal capsulotomy. All patients did not close the capsule. Clinical outcomes were measured with the Hip Outcome Score Activities of Daily Living (HOS-ADL) and the modified Harris Hip Score (mHHS), patient satisfaction measured with visual analogue scale (VAS). The healing of the capsule was evaluated by MRI. MRI showed continuous capsular indicated healing, discontinuous capsular indicated unhealing. Postoperatively 6 months, mHHS and HOS-ADL were obtained. Randomized controlled trials were used in this study for analysis. RESULTS: All patients were followed up with average time of 9.3 months(3-29 months). The postoperative symptoms were obviously relieved, the VAS decreased from (4.9 ± 0.6) to (1.2 ± 0.2) after 3 months postoperative. Follow up 6 months post-operation, patients in the interportal group, the mHHS and HOS-ADL scores improvement were respectively 69.4 ± 9.3 & 70 ± 8.8 pre-operation, and 92.5 ± 5.0 & 86.6 ± 5.4 post-operation (P < 0.05); Patients in the periportal group, the mHHS and HOS-ADL scores improvement were respectively 69.9 ± 15.8, 68.1 ± 15.0 pre-operation, and 90.1 ± 9.3 & 86.7 ± 7.9 post-operation (P < 0.05).The differences were statistically significant. Six months after operation, MRI showed that 23 patients with periportal capsulotomy, the capsule have healed, without other complications. Three of the ten patients with interportal capsulotomy were healed and seven were not. CONCLUSION: Interportal and periportal capsulotomy had good outcomes. The technique of periportal capsulotomy had little damage to the joint capsule. Although the capsule did not close, the capsule healed well in postoperative follow-up. The nonunion rate of the joint capsule was high in the interportal capsulotomy without close the capsule.


Arthroscopy/methods , Cartilage, Articular/injuries , Cartilage, Articular/surgery , Femoracetabular Impingement/surgery , Hip Injuries/surgery , Joint Capsule Release/methods , Adult , Aged , Female , Humans , Male , Middle Aged , Pain Measurement , Patient Reported Outcome Measures , Retrospective Studies
8.
Cell Death Dis ; 12(8): 744, 2021 07 27.
Article En | MEDLINE | ID: mdl-34315853

Multifunctional N6-methyladenosine (m6A) has been revealed to be an important epigenetic component in various physiological and pathological processes, but its role in female ovarian aging remains unclear. Thus, we demonstrated m6A demethylase FTO downregulation and the ensuing increased m6A in granulosa cells (GCs) of human aged ovaries, while FTO-knockdown GCs showed faster aging-related phenotypes mediated. Using the m6A-RNA-sequence technique (m6A-seq), increased m6A was found in the FOS-mRNA-3'UTR, which is suggested to be an erasing target of FTO that slows the degradation of FOS-mRNA to upregulate FOS expression in GCs, eventually resulting in GC-mediated ovarian aging. FTO acts as a senescence-retarding protein via m6A, and FOS knockdown significantly alleviates the aging of FTO-knockdown GCs. Altogether, the abovementioned results indicate that FTO in GCs retards FOS-dependent ovarian aging, which is a potential diagnostic and therapeutic target against ovarian aging and age-related reproductive diseases.


Adenosine/analogs & derivatives , Aging/metabolism , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics , Granulosa Cells/metabolism , Ovary/metabolism , Proto-Oncogene Proteins c-fos/metabolism , 3' Untranslated Regions/genetics , Adenosine/metabolism , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/metabolism , Case-Control Studies , Cell Line , Down-Regulation/genetics , Female , Gene Silencing , Humans , Methylation , Models, Biological , Proto-Oncogene Proteins c-fos/genetics , RNA Stability/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reactive Oxygen Species/metabolism , Up-Regulation/genetics
9.
Angew Chem Int Ed Engl ; 60(10): 5157-5161, 2021 03 01.
Article En | MEDLINE | ID: mdl-33241876

Single-cell and in situ cell-based operation with nanopipette approach offers a possibility to elucidate the intracellular processes and may aid the improvement of therapy efficiency and precision. We present here a photo-responsive hydrogel-nanopipette hybrid system that can achieve single-cell operation with high spatial/temporal resolution and negligible cell damage. This strategy overcomes long-time obstacles in nanopipette single-cell studies as high electric potential (ca. 1000 mV) or organic solvent is always used during operations, which would inevitably impose disturbance and damage to targeted cells. The light-triggered system promotes a potential-free, non-invasive single-cell injection, resulting in a well-retained cell viability (90 % survival rate). Moreover, the photo-driven injection enables a precisely dose-controllable single-cell drug delivery. Significantly reduced lethal doses of doxorubicin (163-217 fg cell-1 ) are demonstrated in corresponding cell lines.


Drug Delivery Systems/methods , Hydrogels/chemistry , Injections/instrumentation , A549 Cells , Antineoplastic Agents/pharmacology , Cell Survival/physiology , Doxorubicin/pharmacology , Drug Delivery Systems/instrumentation , Humans , Hydrogels/radiation effects , Light
10.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3273-3281, 2020 Oct.
Article Zh | MEDLINE | ID: mdl-33314815

To understand the damage capability of the invasive pest Spodoptera frugiperda on diffe-rent corn varieties in China, we evaluated survival fitness of S. frugiperda on three varieties of sweet corn (i.e., Suitian No.1, Zhengtian 68, and Huajintian No.1) and three varieties of waxy corn (i.e., Jingkenuo 2000, Guangheitiannuo, and Guangnuo No.1) by constructing life table for all populations. The correlation of biological parameters of S. frugiperda to the main nutrients and crude fiber content in corn leaves were analyzed. Results showed that the larva survival rate, pupal weight, and production of S. frugiperda on sweet corns were significantly higher than those on waxy corns. The intrinsic rate of increase (rm) of S. frugiperda on the sweet corns ranged from 0.1566 to 0.1843, and the net reproductive rate (R0) ranged from 187.97 to 353.35, being higher than those reared on the waxy corns (rm was from 0.0998 to 0.1465, and R0 was from 25.89 to 95.34). S. frugiperda reared on the sweet corns had higher population growth ability than those reared on the waxy corns. The content of main nutrients such as vitamin C, starch, soluble sugar, protein, fat, total amino acids, and crude fiber in the sweet corn leaves were higher than those in the waxy corn leaves. There were positive correlations between R0 of S. frugiperda to the contenst of vitamin C, starch, soluble sugar, protein, and crude fiber in corn leaves. The results indicated that S. frugiperda reared on the sweet corn leaves had higher survival fitness than those reared on the waxy corn leaves.


Reproduction , Zea mays , Animals , China , Larva , Pupa , Spodoptera
11.
Phys Rev E ; 102(4-1): 042214, 2020 Oct.
Article En | MEDLINE | ID: mdl-33212672

The impact of the classical dynamic on the fluctuation properties in the eigenvalue spectrum of nonrelativistic quantum billiards (QBs) are now well understood based on the semiclassical approach which provides an approximation for the fluctuating part ρ^{fluc}(k) of the spectral density in terms of a trace formula, that is, a sum over classical periodic orbits of its classical counterpart, abbreviated as CB. This connection between the eigenvalue spectrum of a quantum system and the classical periodic orbits is discernible in the Fourier transform of ρ^{fluc}(k) from eigenwave number k to length, which exhibits peaks at the lengths of the periodic orbits. The uprise of interest in properties of graphene related to their relativistic Dirac spectrum implicated the emergence of intensive studies of relativistic neutrino billiards (NBs), consisting of a spin-1/2 particle governed by the Dirac equation and confined to a bounded planar domain. In distinction to QBs, NBs do not have a well-defined classical limit. Yet comparison of their length spectra showed that for massless spin-1/2 particles those of the NB exhibit peaks at positions corresponding to the lengths of periodic orbits with an even number of reflections at the boundary of the CB associated with the corresponding QB. In order to understand the transition from the relativistic to the nonrelativistic regime, we derive an exact quantization condition for massive NBs and use it to obtain a trace formula. This trace formula provides a direct link between the spectral density of a NB and the classical dynamic of the corresponding QB through the periodic orbits of the associated CB.

12.
Phys Rev E ; 101(6-1): 062201, 2020 Jun.
Article En | MEDLINE | ID: mdl-32688565

Systems with discrete symmetries are highly important in quantum mechanics. We consider a two-dimensional quantum billiard with fourfold rotational symmetry, where the eigenenergies and eigenstates can be grouped into four symmetry subspaces. Unlike the threefold rotational symmetry case, here the interference of the scarring states on the fundamental domain orbits (FDO) is clean, that they either interfere constructively or annihilate completely. We shall show the complex behavior of the interference revealed in the length spectra for eigenenergies that belong to a particular symmetry subspace and combinations of different symmetry subspaces. We then provide detailed analysis of phase accumulation along the FDOs, which are the keys to determine the interference and could explain the enhancement or annihilation of the peaks well. The quantization condition for the scarring states belonging to different symmetry subspaces is discussed and used to reveal the time-reversal symmetry broken for a particular subspace. An experimental scheme to observe such complex behaviors is also proposed.

13.
Int J Nanomedicine ; 14: 8989-9006, 2019.
Article En | MEDLINE | ID: mdl-31819414

OBJECTIVE: The objective of this study was to develop magnetic embolic microspheres that could be visualized by clinical magnetic resonance imaging (MRI) scanners aiming to improve the efficiency and safety of embolotherapy. METHODS AND DISCUSSION: Magnetic ferrite nanoclusters (FNs) were synthesized with microwave-assisted solvothermal method, and their morphology, particle size, crystalline structure, magnetic properties as well as T2 relaxivity were characterized to confirm the feasibility of FNs as an MRI probe. Magnetic polymer microspheres (FNMs) were then produced by inverse suspension polymerization with FNs embedded inside. The physicochemical and mechanical properties (including morphology, particle size, infrared spectra, elasticity, etc.) of FNMs were investigated, and the magnetic properties and MRI detectable properties of FNMs were also assayed by vibrating sample magnetometer and MRI scanners. Favorable biocompatibility and long-term MRI detectability of FNMs were then studied in mice by subcutaneous injection. FNMs were further used to embolize rabbits' kidneys to evaluate the embolic property and detectability by MRI. CONCLUSION: FNMs could serve as a promising MRI-visualized embolic material for embolotherapy in the future.


Embolization, Therapeutic , Ferric Compounds/chemistry , Magnetic Resonance Imaging , Magnetics , Microspheres , Nanoparticles/chemistry , Polymers/chemistry , Animals , Dynamic Light Scattering , Elasticity , Female , Iron/metabolism , Kidney/diagnostic imaging , Kidney/pathology , Male , Mice , Nanoparticles/ultrastructure , Particle Size , Photoelectron Spectroscopy , Rabbits
15.
Angew Chem Int Ed Engl ; 57(27): 8105-8109, 2018 07 02.
Article En | MEDLINE | ID: mdl-29697897

The light-induced reversible and cyclic reconfiguration of constitutional dynamic networks, consisting of supramolecular nucleic acid structures as constituents and a photoisomerizable trans/cis-azobenzene-functionalized nucleic acid as the trigger is demonstrated. In addition, the cyclic photochemical reconfiguration of the constitutional dynamic networks guides the switchable on/off operation of an emerging hemin/G-quadruplex DNAzyme.


DNA/chemistry , Light , Azo Compounds/chemistry , Catalysis , DNA, Catalytic/chemistry , DNA, Catalytic/metabolism , G-Quadruplexes , Hemin/chemistry , Isomerism , Oxazines/chemistry , Oxidation-Reduction
16.
Anal Chem ; 90(7): 4268-4272, 2018 04 03.
Article En | MEDLINE | ID: mdl-29516718

Identification of the configuration for the photoresponsive oligonucleotide plays an important role in the ingenious design of DNA nanomolecules and nanodevices. Due to the limited resolution and sensitivity of present methods, it remains a challenge to determine the accurate configuration of photoresponsive oligonucleotides, much less a precise description of their photoconversion process. Here, we used an aerolysin (AeL) nanopore-based confined space for real-time determination and quantification of the absolute cis/ trans configuration of each azobenzene-modified oligonucleotide (Azo-ODN) with a single molecule resolution. The two completely separated current distributions with narrow peak widths at half height (<0.62 pA) are assigned to cis/ trans-Azo-ODN isomers, respectively. Due to the high current sensitivity, each isomer of Azo-ODN could be undoubtedly identified, which gives the accurate photostationary conversion values of 82.7% for trans-to- cis under UV irradiation and 82.5% for cis-to- trans under vis irradiation. Further real-time kinetic evaluation reveals that the photoresponsive rate constants of Azo-ODN from trans-to- cis and cis-to -trans are 0.43 and 0.20 min-1, respectively. This study will promote the sophisticated design of photoresponsive ODN to achieve an efficient and applicable photocontrollable process.


Bacterial Toxins/chemistry , Nanopores , Oligonucleotides/analysis , Pore Forming Cytotoxic Proteins/chemistry , Photochemical Processes , Stereoisomerism , Time Factors
17.
Chem Commun (Camb) ; 53(68): 9462-9465, 2017 Aug 22.
Article En | MEDLINE | ID: mdl-28795695

Herein, the structural stability of single azobenzene modified DNA duplexes, including the trans form and cis form, has been examined separately based on their distinguishable unzipping kinetics from the mixture by an α-hemolysin nanopore. Furthermore, the accurate isomerization efficiency between the trans and cis form was obtained with single molecule resolution.


Azo Compounds/chemistry , DNA/chemistry , Hemolysin Proteins/chemistry , Molecular Structure , Photochemical Processes
18.
Int J Pharm ; 527(1-2): 31-41, 2017 Jul 15.
Article En | MEDLINE | ID: mdl-28487188

To develop embolic microspheres with MRI detectability, superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized and mixed with monomer of acrylic acid to prepare SPIONs-loaded polymerized microspheres (SPMs) by inverse suspension polymerization method. The SPMs were evaluated for the ability of embolization by investigating the morphology, particle size, elasticity and renal arterial embolization to rabbits. Meanwhile, the loading of SPIONs was verified by optical microscope, transmission electron microscope, Fourier transform infrared spectrum, vibrating sample magnetometer, X-ray diffraction and X-ray photoelectron spectroscopy, and the content of SPIONs in SPMs was measured quantitatively. Furthermore, the MRI detectability of SPMs was testified in gel phantom, mice and rabbits respectively by a clinical 3.0T MRI scanner. The results revealed the SPMs were potential MRI detectable embolic microspheres for improving the effectiveness and safety of embolotherapy in the future.


Acrylic Resins/chemistry , Embolization, Therapeutic , Magnetite Nanoparticles/chemistry , Microspheres , Animals , Magnetic Resonance Imaging , Male , Mice , Rabbits
19.
Int J Pharm ; 511(2): 831-9, 2016 Sep 25.
Article En | MEDLINE | ID: mdl-27426106

To monitor the spatial distribution of embolic particles inside the target tissues during and after embolization, blank poly (acrylic acid) microspheres (PMs) were initially prepared by inverse suspension polymerization method and then loaded with superparamagnetic iron oxide (SPIO) nanoparticles by in situ precipitation method to obtain magnetic resonance imaging (MRI) detectable SPIO-loaded poly (acrylic acid) microspheres (SPMs). The loading of SPIO nanoparticles in SPMs was confirmed by vibrating sample magnetometer, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and infrared spectrum, respectively. The results showed that SPMs exhibited excellent superparamagnetism and the SPIO embedded in SPMs were proved to be inverse spinel magnetite. The content of SPIO loaded in wet SPMs of subgroups of 100-300, 300-500, 500-700 and 700-900µm was measured to be 11.84±0.07, 10.20±0.05, 9.98±0.00 and 8.79±0.01mg/ml, corresponding to the weight percentage in freeze-dried SPMs to be 18.07±0.28%, 18.54±0.13%, 18.66±0.01% and 18.50±0.07%, respectively. The SPMs were spherical in shape, had smooth surface, and were within the size range of clinical demands for embolization. The compression tests indicated that SPMs were more rigid than PMs and commercially used Embospheres (P<0.01). The MRI detectability of SPMs was evaluated with the SPMs embedded in gel phantom in vitro and injected subcutaneously into the back of mice in vivo. Both the results demonstrated that the SPMs could provide distinct negative contrast enhancement and be sensitively detected by T2-weighted MR imaging. All the results show that SPMs are potential MRI detectable embolic microspheres for the future embolotherapy.


Acrylic Resins/chemistry , Embolization, Therapeutic/methods , Microspheres , Animals , Contrast Media/administration & dosage , Contrast Media/chemistry , Elasticity , Injections, Subcutaneous , Magnetic Phenomena , Magnetic Resonance Imaging , Magnetite Nanoparticles/administration & dosage , Magnetite Nanoparticles/chemistry , Magnetite Nanoparticles/ultrastructure , Male , Mice , Particle Size , Phantoms, Imaging
20.
Phys Rev E ; 94(6-1): 062214, 2016 Dec.
Article En | MEDLINE | ID: mdl-28085331

A crucial result in quantum chaos, which has been established for a long time, is that the spectral properties of classically integrable systems generically are described by Poisson statistics, whereas those of time-reversal symmetric, classically chaotic systems coincide with those of random matrices from the Gaussian orthogonal ensemble (GOE). Does this result hold for two-dimensional Dirac material systems? To address this fundamental question, we investigate the spectral properties in a representative class of graphene billiards with shapes of classically integrable circular-sector billiards. Naively one may expect to observe Poisson statistics, which is indeed true for energies close to the band edges where the quasiparticle obeys the Schrödinger equation. However, for energies near the Dirac point, where the quasiparticles behave like massless Dirac fermions, Poisson statistics is extremely rare in the sense that it emerges only under quite strict symmetry constraints on the straight boundary parts of the sector. An arbitrarily small amount of imperfection of the boundary results in GOE statistics. This implies that, for circular-sector confinements with arbitrary angle, the spectral properties will generically be GOE. These results are corroborated by extensive numerical computation. Furthermore, we provide a physical understanding for our results.

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