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2.
BMC Plant Biol ; 24(1): 546, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38872113

ABSTRACT

BACKGROUND: Apple Replant Disease (ARD) is common in major apple-growing regions worldwide, but the role of rhizosphere microbiota in conferring ARD resistance and promoting plant growth remains unclear. RESULTS: In this study, a synthetic microbial community (SynCom) was developed to enhance apple plant growth and combat apple pathogens. Eight unique bacteria selected via microbial culture were used to construct the antagonistic synthetic community, which was then inoculated into apple seedlings in greenhouse experiments. Changes in the rhizomicroflora and the growth of aboveground plants were monitored. The eight strains, belonging to the genera Bacillus and Streptomyces, have the ability to antagonize pathogens such as Fusarium oxysporum, Rhizoctonia solani, Botryosphaeria ribis, and Physalospora piricola. Additionally, these eight strains can stably colonize in apple rhizosphere and some of them can produce siderophores, ACC deaminase, and IAA. Greenhouse experiments with Malus hupehensis Rehd indicated that SynCom promotes plant growth (5.23%) and increases the nutrient content of the soil, including soil organic matter (9.25%) and available K (1.99%), P (7.89%), and N (0.19%), and increases bacterial richness and the relative abundance of potentially beneficial bacteria. SynCom also increased the stability of the rhizosphere microbial community, the assembly of which was dominated by deterministic processes (|ß NTI| > 2). CONCLUSIONS: Our results provide insights into the contribution of the microbiome to pathogen inhibition and host growth. The formulation and manipulation of similar SynComs may be a beneficial strategy for promoting plant growth and controlling soil-borne disease.


Subject(s)
Malus , Plant Diseases , Rhizosphere , Malus/microbiology , Malus/growth & development , Plant Diseases/microbiology , Plant Diseases/prevention & control , Soil Microbiology , Microbiota/physiology , Rhizoctonia/physiology , Biological Control Agents , Bacillus/physiology , Antibiosis
3.
Physiol Plant ; 176(2): e14271, 2024.
Article in English | MEDLINE | ID: mdl-38566130

ABSTRACT

Seed dormancy is an important life history state in which intact viable seeds delay or prevent germination under suitable conditions. Ascorbic acid (AsA) acts as a small molecule antioxidant, and breaking seed dormancy and promoting subsequent growth are among its numerous functions. In this study, a germination test using Pyrus betulifolia seeds treated with exogenous AsA or AsA synthesis inhibitor lycorine (Lyc) and water absorption was conducted. The results indicated that AsA released dormancy and increased germination and 20 mmol L-1 AsA promoted cell division, whereas Lyc reduced germination. Seed germination showed typical three phases of water absorption; and seeds at five key time points were sampled for transcriptome analysis. It revealed that multiple pathways were involved in breaking dormancy and promoting germination through transcriptome data, and 12 differentially expressed genes (DEGs) related to the metabolism and signal transduction of abscisic acid (ABA) and gibberellins (GA) were verified by subsequent RT-qPCR. For metabolites, exogenous AsA increased endogenous AsA and GA3 but reduced ABA and the ABA/GA3 ratio. In addition, three genes regulating ABA synthesis were downregulated by AsA, while five genes mediating ABA degradation were upregulated. Taken together, AsA regulates the pathways associated with ABA and GA synthesis, catalysis, and signal transduction, with subsequent reduction in ABA and increase in GA and further the balance of ABA/GA, ultimately releasing dormancy and promoting germination.


Subject(s)
Gibberellins , Pyrus , Gibberellins/pharmacology , Gibberellins/metabolism , Abscisic Acid/pharmacology , Abscisic Acid/metabolism , Germination , Plant Growth Regulators/pharmacology , Plant Growth Regulators/metabolism , Pyrus/metabolism , Ascorbic Acid/metabolism , Plant Dormancy/genetics , Seeds , Water/metabolism , Gene Expression Regulation, Plant
4.
ACS Appl Mater Interfaces ; 16(14): 17242-17252, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38556729

ABSTRACT

Protective autophagy and DNA damage repair lead to tumor radio-resistance. Some hypoxic tumors exhibit a low radiation energy absorption coefficient in radiation therapy. High doses of X-rays may lead to side effects in the surrounding normal tissues. In order to overcome the radio-resistance and improve the efficacy of radiotherapy based on the characteristics of the tumor microenvironment, the development of radiosensitizers has attracted much attention. In this study, a Janus ACSP nanoparticle (NP) was developed for chemodynamic therapy and radiosensitization. The reactive oxygen species generated by the Fenton-like reaction regulated the distribution of cell cycles from a radioresistant phase to a radio-sensitive phase. The high-Z element, Au, enhanced the production of hydroxyl radicals (•OH) under X-ray radiation, promoting DNA damage and cell apoptosis. The NP delayed DNA damage repair by interfering with certain proteins involved in the DNA repair signaling pathway. In vivo experiments demonstrated that the combination of the copper-ion-based Fenton-like reaction and low-dose X-ray radiation enhanced the effectiveness of radiotherapy, providing a novel approach for synergistic chemodynamic and radiosensitization therapy. This study provides valuable insights and strategies for the development and application of NPs in cancer treatment.


Subject(s)
Nanoparticles , Neoplasms , Radiation-Sensitizing Agents , Humans , Neoplasms/drug therapy , Radiation-Sensitizing Agents/pharmacology , Radiation-Sensitizing Agents/therapeutic use , Apoptosis , Cell Line, Tumor , Tumor Microenvironment , Hydrogen Peroxide
5.
Nucl Med Commun ; 45(2): 148-154, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38095143

ABSTRACT

OBJECTIVE: To explore the value of 18 F-FDG PET/CT tumor metabolic heterogeneity index (HI) and establish and validate a nomogram model for distinguishing head and neck cancer of unknown primary (HNCUP) from lymphoma with head and neck metastatic poorly differentiated cancer. METHODS: This retrospective analysis was conducted on 1242 patients with cervical metastatic poorly differentiated cancer. 108 patients, who were clinically and pathologically confirmed as HNCUP or lymphoma, were finally enrolled. Two independent sample t-tests and χ 2 test were used to compare the clinical and imaging features. Binary logistic regression was used to screen for independent predictive factors. RESULTS: Among the 108 patients), 65 patients were diagnosed with HNCUP and 43 were lymphoma. Gender ( P  = 0.001), SUV max ( P  < 0.001), SUV mean ( P  < 0.001), TLG ( P  = 0.012), and HI ( P  < 0.001) had statistical significance in distinguishing HNCUP and lymphoma. Female ( OR  = 4.546, P  = 0.003) and patients with HI ≥ 2.37 ( OR  = 3.461, P  = 0.047) were more likely to be diagnosed as lymphoma. CONCLUSION: For patients with cervical metastatic poorly differentiated cancer, gender and HI were independent predictors of pathological type. For such patients, clinical attention should be paid to avoid misdiagnosing lymphoma as HNCUP, which may delay treatment.


Subject(s)
Head and Neck Neoplasms , Lymphoma , Neoplasms, Unknown Primary , Humans , Female , Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography/methods , Retrospective Studies , Head and Neck Neoplasms/diagnostic imaging , Lymphoma/diagnostic imaging , Radiopharmaceuticals
6.
Polymers (Basel) ; 15(19)2023 Sep 29.
Article in English | MEDLINE | ID: mdl-37835982

ABSTRACT

With the rapid advancement of intelligent electronics, big data platforms, and other cutting-edge technologies, traditional low dielectric polymer matrix composites are no longer sufficient to satisfy the application requirements of high-end electronic information materials, particularly in the realm of high integration and high-frequency, high-speed electronic communication device manufacturing. Consequently, resin-based composites with exceptional low dielectric properties have garnered unprecedented attention. In recent years, benzoxazine-based composites have piqued the interest of scholars in the fields of high-temperature-resistant, low dielectric electronic materials due to their remarkable attributes such as high strength, high modulus, high heat resistance, low curing shrinkage, low thermal expansion coefficient, and excellent flame retardancy. This article focuses on the design and development of modification of polybenzoxazine based on low dielectric polybenzoxazine modification methods. Studies on manufacturing polybenzoxazine co-polymers and benzoxazine-based nanocomposites have also been reviewed.

7.
Polymers (Basel) ; 15(17)2023 Aug 23.
Article in English | MEDLINE | ID: mdl-37688142

ABSTRACT

Self-polymerization epoxy/phthalonitrile (APPEN) pre-polymers were studied systematically, and then, gelation time and differential scanning calorimetry (DSC) were employed to investigate their curing behaviors. Taking advantage of orthogonal test analysis, the key factors that affected the co-polymerization of APPEN were defined and the appropriate pre-polymerization conditions were analyzed. A possible curing mechanism of APPEN was proposed. Then, the thermomechanical and mechanical properties of glass-fiber-reinforced APPEN laminates (APPEN/GF) prepared at 180 °C were analyzed to understand the cross-linked and aggregation structures. Fracture surface of the composite laminates was also investigated to reveal the copolymerization degree and the interfacial binding. The results indicated that APPEN/GF composites exhibit outstanding mechanical and thermomechanical properties (flexural strength, 712 MPa, flexural modulus, 38 GPa, and Tg > 185 °C). The thermal stability (T5% > 334 °C and IPDT reached 1482 °C) of APPEN/GF composites was also investigated to further reveal the copolymerization between epoxy resin and aminophthalonitrile, which may be beneficial to the application of epoxy-matrix-based composites in the field of high-performance polymer composites.

8.
Eur J Nucl Med Mol Imaging ; 50(13): 3996-4009, 2023 11.
Article in English | MEDLINE | ID: mdl-37596343

ABSTRACT

PURPOSE: Prognostic prediction is crucial to guide individual treatment for locoregionally advanced nasopharyngeal carcinoma (LA-NPC) patients. Recently, multi-task deep learning was explored for joint prognostic prediction and tumor segmentation in various cancers, resulting in promising performance. This study aims to evaluate the clinical value of multi-task deep learning for prognostic prediction in LA-NPC patients. METHODS: A total of 886 LA-NPC patients acquired from two medical centers were enrolled including clinical data, [18F]FDG PET/CT images, and follow-up of progression-free survival (PFS). We adopted a deep multi-task survival model (DeepMTS) to jointly perform prognostic prediction (DeepMTS-Score) and tumor segmentation from FDG-PET/CT images. The DeepMTS-derived segmentation masks were leveraged to extract handcrafted radiomics features, which were also used for prognostic prediction (AutoRadio-Score). Finally, we developed a multi-task deep learning-based radiomic (MTDLR) nomogram by integrating DeepMTS-Score, AutoRadio-Score, and clinical data. Harrell's concordance indices (C-index) and time-independent receiver operating characteristic (ROC) analysis were used to evaluate the discriminative ability of the proposed MTDLR nomogram. For patient stratification, the PFS rates of high- and low-risk patients were calculated using Kaplan-Meier method and compared with the observed PFS probability. RESULTS: Our MTDLR nomogram achieved C-index of 0.818 (95% confidence interval (CI): 0.785-0.851), 0.752 (95% CI: 0.638-0.865), and 0.717 (95% CI: 0.641-0.793) and area under curve (AUC) of 0.859 (95% CI: 0.822-0.895), 0.769 (95% CI: 0.642-0.896), and 0.730 (95% CI: 0.634-0.826) in the training, internal validation, and external validation cohorts, which showed a statistically significant improvement over conventional radiomic nomograms. Our nomogram also divided patients into significantly different high- and low-risk groups. CONCLUSION: Our study demonstrated that MTDLR nomogram can perform reliable and accurate prognostic prediction in LA-NPC patients, and also enabled better patient stratification, which could facilitate personalized treatment planning.


Subject(s)
Deep Learning , Nasopharyngeal Neoplasms , Humans , Prognosis , Nomograms , Nasopharyngeal Carcinoma/diagnostic imaging , Positron Emission Tomography Computed Tomography/methods , Fluorodeoxyglucose F18 , Nasopharyngeal Neoplasms/diagnostic imaging , Retrospective Studies
9.
Comput Struct Biotechnol J ; 19: 2236-2245, 2021.
Article in English | MEDLINE | ID: mdl-33995916

ABSTRACT

Acupuncture has been used for treating various medical conditions in traditional Chinese medicine. Both manual and electro-acupuncture stimulate specific acupoints to obtain local and systemic biological effects, but the underlying mechanisms remain unclear. Here, we used three-dimensional tissue-clearing technology to study acupoints on the Ren meridian of mice to reveal the distribution, density, branching, and relationships between blood vessels and nerves. Using topological Mapper methods, we found that sympathetic neurovascular networks were denser in the CV 4 acupoint compared with surrounding non-acupoints. Furthermore, high resolution in vivo real-time vascular imaging using the near infrared-II probe LZ-1105 demonstrated increased blood flow in the CV 4 acupoint compared with neighboring non-acupoints after manual or electro-acupuncture. Consistent with earlier findings, our research indicated that acupuncture could enhance local blood flow, and our high-resolution 3D images show for the first time the important role of sympathetic neurovascular networks in the CV 4 acupoint.

10.
Saudi J Med Med Sci ; 8(3): 196-200, 2020.
Article in English | MEDLINE | ID: mdl-32952511

ABSTRACT

BACKGROUND: Uridine 5'-diphospho-glucuronosyltransferase (UGT) enzymes play a significant role in the metabolism of quetiapine, and coadministration with a UGT inhibitor/inducer drug may change its pharmacokinetic profile. OBJECTIVE: The objective of this study was to assess the impact of probenecid, a UGT enzyme inhibitor, on the pharmacokinetic profile of quetiapine. MATERIALS AND METHODS: Twelve treatment-naïve, 7-week-old male Sprague-Dawley rats (weighting 161 ± 22 g) were randomly and equally divided into control, quetiapine-alone and quetiapine plus probenecid groups. The quetiapine plus probenecid group received a single oral dose of probenecid (50 mg/kg) followed by 50 mg/kg of quetiapine; the quetiapine-alone group only received 50 mg/kg of quetiapine. Blood samples (0.2 ml) were collected from all rats after 0, 0.25, 0.5, 1, 2, 4, 6, 8, 10, 12 and 24 h of the drug administration in heparinized tubes. The pre-established liquid chromatography-mass spectrometry method was utilized to ascertain the plasma concentration of quetiapine and the control group was used to prepare the controlled standard. RESULTS: Significant pharmacokinetic differences were observed between the quetiapine-alone and quetiapine plus probenecid groups in terms of Cmax (392 ± 209 vs. 1323 ± 343 ug/L, respectively, P = 0.004), AUC0-∞ (P = 0.04) and Tmax (P = 0.004). Further, in the combined drug group, there was a decrease in drug clearance (CL/F) (from 27 ± 11 to 16 ± 3 L/h/kg; P = 0.005) and an increase in the volume of distribution (Vd) (P = 0.01), but there was no significant difference between both groups in terms of half-lives (P = 0.27). No significant within-group variability of pharmacokinetic parameters was observed (P = 0.25). CONCLUSION: The results of this animal study suggest that glucuronidation by UGT enzyme system may also play an important role in quetiapine metabolism, which, if proven in future human studies, would imply that the bioavailability and pharmacokinetic parameters of quetiapine may require alterations when co-administered with probenecid to avoid development of quetiapine toxicity.

11.
Front Physiol ; 11: 474, 2020.
Article in English | MEDLINE | ID: mdl-32547407

ABSTRACT

Low-frequency electro-acupuncture (EA) has been shown to restore ovulation in patients with polycystic ovary syndrome (PCOS), and previous animal experiments showed that EA improves ovarian blood flow and angiogenesis. We performed EA for 4 weeks in dihydrotestosterone (DHT)-induced PCOS-like rats and investigated the three-dimensional (3D) ovarian innervation to determine the role of innervation in folliculogenesis and vascularity. Ovarian tissues were made transparent following the CUBIC 3D tissue-clearing protocol and were immunostained using antibodies against platelet endothelial cell adhesion molecule-1 and tyrosine hydroxylase to visualize the ovarian vasculature and innervation, respectively. This was followed by 3D imaging using lightsheet microscopy and analysis using the Imaris software. In control rats, ovarian innervation increased with age, and the neuronal branching started from the ovarian hilum and reached the individual follicles at different follicle stages. At the individual follicle level, each follicle was mainly innervated by one neuronal fiber. Compared with control rats, ovaries from DHT-treated PCOS-like rats had more antral follicles and fewer preovulatory follicles and corpora lutea. Furthermore, PCOS ovaries showed decreased innervation of blood vessels near the hilum and the surrounding individual antral follicles. EA in PCOS-like rats led to increased numbers of preovulatory follicles and corpora lutea together with increased innervation of blood vessels near the hilum. To determine the role of ovarian innervation, we further performed unilateral sectioning of the superior ovarian nerve (SON) in PCOS + EA rats and found that the left sectioned ovary had fewer preovulatory follicles and corpora lutea compared with those in the right non-sectioned ovary. In conclusion, ovarian innervation likely played an important role in folliculogenesis, and EA might restore PCOS pathophysiology by regulating ovarian innervation, at least partially mediated through the SON.

12.
Nanomaterials (Basel) ; 9(10)2019 Sep 21.
Article in English | MEDLINE | ID: mdl-31546667

ABSTRACT

Dye pollution is a serious problem in modern society. We desired to develop an efficient adsorbent for the decontamination of discharged dyes. In this work, the polymeric microspheres derived from a kind of amphiphilic block of co-poly(arylene ether nitrile) (B-b-S-P) were prepared on the basis of "oil-in-water" (O/W) microemulsion method. The B-b-S-P microspheres were found competent to remove the cationic dye, methylene blue (MB); and various influential factors, such as contact time, initial concentration, solution pH and temperature were investigated. Results indicated that the maximum adsorption capacity of B-b-S-P microspheres for MB was 119.84 mg/g at 25 °C in neutral conditions. Adsorption kinetics and isotherm dates were well fitted to a pseudo-second-order kinetic model and the Langmuir isotherm model, and thermodynamic parameters implied that the adsorption process was endothermic. The B-b-S-P microspheres also exhibited a highly selective adsorption for cationic dye MB, even in the presence of anionic dye methyl orange (MO). In addition, the possible adsorption mechanism was studied, suggesting that the electrostatic interaction and π-π interaction could be the main force in the adsorption process.

13.
Urology ; 133: e9-e10, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31352018

ABSTRACT

Bladder outlet obstruction (BOO) is a common urological condition usually caused by benign prostatic hyperplasia, prostate cancer, urethral stricture, rarely by compression of surrounding organs. Herein we presented a BOO patient caused by the compression of displaced hemipelvic prosthesis after pelvic reconstruction. This report may help to increase awareness of BOO as a late complication of pelvic reconstruction.


Subject(s)
Foreign Bodies/complications , Pelvic Bones/surgery , Postoperative Complications/etiology , Prostheses and Implants/adverse effects , Prosthesis Failure/adverse effects , Urinary Bladder Neck Obstruction/etiology , Humans , Male , Middle Aged , Pelvis , Prosthesis Implantation
14.
Polymers (Basel) ; 11(6)2019 Jun 11.
Article in English | MEDLINE | ID: mdl-31212666

ABSTRACT

Benzoxazine containing fluorinated aromatic ether nitrile linkage (FAEN-Bz) had been synthesized from 2,6-dichlorobenzonitrile, 4,4'-(hexafluoroisopropylidene)diphenol (bisphenol AF), 3-Aminophenol, formaldehyde, phenol by condensation polymerization and Mannich ring-forming reaction. Structures of the monomer were verified by Proton NMR spectrum (1H-NMR) and Fourier transform infrared spectroscopy (FTIR). Curing behaviors and curing kinetics of designed monomers were investigated and discussed. The activation energy was calculated and possible polymerization mechanisms were also proposed. Then, properties of cured polymers including crosslinking degrees, thermal decomposition, surface wettability and energy, and dielectric properties were studied and discussed. Additionally, programmed integral decomposition temperature (IPDT) was also used to evaluate the thermal stability of final polymers. Results indicated that the incorporation of benzoxazine and nitrile resulted in increased thermal stability and char yields. Moreover, the surface wettability and dielectric properties of poly(FAEN-Bz) can be easily controlled by tuning the curing temperatures and time.

15.
Nanomaterials (Basel) ; 8(12)2018 Dec 03.
Article in English | MEDLINE | ID: mdl-30513909

ABSTRACT

Epoxy/cyanate resin matrix composites (AG80/CE) with improved thermal conductivity and mechanical properties were obtained with synergetic enhancement with functional carbon nanotubes (f-CNTs) and hexagonal boron nitride (h-BN). AG80/CE performed as polymeric matrix and h-BN as conductivity filler which formed the main thermal conductivity channels. Small amounts of f-CNTs were introduced to repair defects in conductivity channels and networks. To confirm the synergetic enhancements, the thermal conductivity was investigated and analyzed with Agari's model. Results indicated that with introduction of 0.5 wt% f-CNTs, the thermal conductivity coefficient (ƛ) increased to 0.745 W/mk, which is 1.38 times that of composites with just h-BN. Furthermore, the flexural strength and modulus of composites with 0.5 wt% f-CNTs were 85 MPa and 3.5 GPa. The glass transition temperature (Tg) of composites with 0.4 wt% was 285 °C and the initial decomposition temperature (T5%) was 385 °C, indicating outstanding thermal stability. The obtained h-BN/f-CNTs reinforced AG80/CE composites present great potential for packaging continuous integration and miniaturization of microelectronic devices.

16.
Materials (Basel) ; 11(8)2018 Aug 05.
Article in English | MEDLINE | ID: mdl-30081589

ABSTRACT

The surface morphology of nanoparticles significantly affects the final properties and interfacial characteristics of their composites. Thus, investigations on the surface morphology of the nanoparticles is essential to fabricate improved nanoparticle-reinforced composites. Fe3O4/Fe-phthalocyanine (FePc) hybrid microspheres with micro/mesoporous structures were prepared via a solvothermal process and solvent etching method. The surface morphology and compositional distribution were respectively investigated using a scanning electron microscope (SEM) and a transmission electron microscope (TEM) to rule out that FePc monomers have been blended with Fe3O4 to form Fe3O4/FePc hybrid microspheres without serious agglomeration. The surface roughness of Fe3O4/FePc microspheres was investigated by the scanning probe microscope (SPM), and confirmed by the adsorption and desorption isotherms of N2. The effects of the various surface morphologies on the crystallization behavior of crystallizable poly(arylene ether nitrile) (c-PEN) were first employed to confirm the surface characteristics of the resulted microspheres. Results indicated that the etched Fe3O4/FePc microspheres would improve the crystallization degree of c-PEN, due to their much more micro/mesoporous structures than that of original Fe3O4/FePc. Then, Fe3O4/FePc hybrid microspheres reinforced PEN composite films were prepared and their interfacial compatibility was monitored using an SEM. Excellent thermal stability and improved mechanical properties were obtained by combining the etched Fe3O4/FePc and PEN matrix. The excellent surface properties and micro/mesoporous structures make the novel Fe3O4/FePc an excellent candidate of organic/inorganic hybrid fillers and micro/mesoporous materials.

17.
Polymers (Basel) ; 10(6)2018 May 29.
Article in English | MEDLINE | ID: mdl-30966630

ABSTRACT

Copolymerization is the typical method to obtain the high-performance resin composites, due to its universality and regulation performance. It can be employed among various resin matrices with active groups to obtain the desired structures, and subsequently, the outstanding properties. In this work, the copolymerization between the allyl-functional phthalonitrile-containing benzoxazine resin (DABA-Ph) and 4,4'-bis(Maleimidodiphenyl)methane (BMI) were monitored. The interactions among the active groups including allyl moieties, maleimide, benzoxazine rings and nitrile groups were investigated. Differential scanning calorimetry (DSC) and dynamic rheological analysis (DRA) were used to study the curing behaviors and the processing properties. The possible curing processes were proposed and confirmed by Fourier transform infrared spectroscopy (FTIR). Then, glass fiber-reinforced DABA-Ph/BMI composites were designed, and their thermal-mechanical properties were studied. Results indicated that all the composites exhibited outstanding flexural strength, flexural modulus, and high glass-transition temperatures (Tg > 450 °C). The thermal stability of the composites was studied by thermogravimetry (TGA) and evaluated by the integral program decomposition temperature (IPDT). it is believed that the excellent thermal mechanical properties and outstanding Tg as well as good thermal stability would enable the reinforced copolymer-based laminates to be applied in wider fields.

18.
Polymers (Basel) ; 10(10)2018 Oct 11.
Article in English | MEDLINE | ID: mdl-30961053

ABSTRACT

The interfacial properties between fibers and resin matrices show great influence on the properties of fiber-reinforced composites. In this work, phthalonitrile containing benzoxazine (BA-ph) was chosen as the resin matrix, which combined with the glass fiber (GF) to prepare reinforced composite laminates at low temperature (200 °C). The poly(arylene ether nitrile) (PEN) was used to modify the GF and BA-ph matrix. Curing behaviors of the BA-ph/PEN were investigated with Differential scanning calorimetric (DSC) and Dynamic rheological analysis (DRA), and results indicated that the polymerization would be hindered by PEN due to the dilution effects. Moreover, the formation of triazine rings which assigning to the ring-forming polymerization of nitrile groups in BA-ph and PEN could improve the compatibility of BA-ph and PEN in the matrix. The SEM images of the fracture surface of the composites revealed that the brittleness of BA-ph matrix and interfacial adhesion between GFs and matrix was improved. The enhanced interfacial adhesion was detailedly discussed from the perspective of physical entanglement and the copolymerization between PEN chains on the surface of GFs and BA-ph/PEN matrix. The results of DMA also explained the toughness of BA-ph/PEN matrix, the semi-interpenetrating polymer networks and the interfacial adhesion. In sum, a feasible strategy that modifies the surface of GFs and the brittleness of the thermosetting matrix by high-performance thermoplastic polymers, which can be employed to prepare the composite laminates with improved properties.

19.
PLoS One ; 11(12): e0167930, 2016.
Article in English | MEDLINE | ID: mdl-27973621

ABSTRACT

BACKGROUND: Atypical antipsychotics such as olanzapine cause metabolic side effects leading to obesity and insulin resistance. The underlying mechanisms remain elusive. In this study we investigated the effects of chronic treatment of olanzapine on the fatty acid composition of plasma in mice. METHODS: Twenty 8-week female Balb/c mice were randomly assigned to two groups: the OLA group and the control group. After treatment with olanzapine (10 mg/kg/day) or vehicle intraperitoneally for 8 weeks, fasting glucose, insulin levels and oral glucose tolerance test were determined. Effects on plasma fatty acid profile and plasma indices of D5 desaturase, D6 desaturase and SCD1 activity were also investigated. RESULTS: Chronic administration of olanzapine significantly elevated fasting glucose and insulin levels, impaired glucose tolerance, but did not increase body weight. Total saturated fatty acids and n-6 polyunsaturated fatty acids were significantly increased and total monounsaturated fatty acids were significantly decreased, while total n-3 polyunsaturated fatty acids showed no prominent changes. Chronic olanzapine treatment significantly up-regulated D6 desaturase activity while down-regulating D5 desaturase activity. Palmitic acid (C16:0), dihomo-γ-linolenic acid (C20:3n-6) and D6 desaturase were associated with an increase probability of insulin resistance, whereas nervonic acid (C24:1) and SCD1 were significantly associated with a lower insulin resistance probability. CONCLUSIONS: All results indicated that such drug-induced effects on fatty acid profile in plasma were relevant for the metabolic adverse effects associated with olanzapine and possibly other antipsychotics. Further studies are needed to investigate geneticand other mechanisms to explain how plasma fatty acids regulate glucose metabolism and affect the risk of insulin resistance.


Subject(s)
Antipsychotic Agents/adverse effects , Benzodiazepines/adverse effects , Fatty Acids/blood , Insulin Resistance , 8,11,14-Eicosatrienoic Acid/blood , Animals , Area Under Curve , Blood Glucose/analysis , Chronic Disease , Fatty Acid Desaturases/metabolism , Female , Glucose Tolerance Test , Insulin/blood , Mice , Mice, Inbred BALB C , Olanzapine , Palmitic Acid/blood , Random Allocation
20.
Adv Ther ; 33(10): 1704-1714, 2016 10.
Article in English | MEDLINE | ID: mdl-27444313

ABSTRACT

INTRODUCTION: The aim of this study was to evaluate the pharmacokinetics (PK) of single and multiple doses of oral lafutidine tablets and the effect of food on the PK properties in healthy Chinese subjects. The tolerability and the effect of gender on the PK properties were also evaluated to acquire more PK information. METHODS: Three PK studies were conducted in 12 healthy Chinese subjects (6 male, 6 female). Study 1 was a single-dose, three-period, three-dose level (10, 20, and 40 mg), three-sequence cross-over study under fasting conditions. Study 2 was a repeat-dose study (10 mg twice daily over 6 days; all 12 subjects). Study 3 was a two-period, two-sequence cross-over single-dose (10 mg) food interaction study. All randomizations (study 1, study 3) were done to ascertain 1:1 gender ratio per sequence. A validated liquid chromatography tandem mass spectrometry (LC/MS/MS) method was used to determine plasma lafutidine concentrations. PK parameters were calculated by the non-compartmental method. RESULTS: The area under the time-concentration curve (AUC) and maximum plasma concentration (C max) of lafutidine tablets were dose-independent in the single-dose study among these healthy volunteers. The PK parameters of the multiple-dose study were inconsistent with the single study. After administration of a single dose of 10 mg under either fed or fasting conditions, we found that food may not affect the degree of absorption of the lafutidine tablets, but it may slow down the absorption rate. This is shown by the fact that the AUC showed no significant difference while the peak time was significantly delayed under fed conditions. CONCLUSION: The PK of lafutidine showed dose proportionality. There was no significant accumulation of lafutidine tablets with multiple dosing. Food did not affect the degree of lafutidine absorption, but it did reduce the rate of absorption. Further study is needed regarding the effect of gender on lafutidine. Lafutidine was well tolerated within the dose range 10-40 mg, and no serious adverse events were observed.


Subject(s)
Acetamides , Piperidines , Pyridines , Acetamides/administration & dosage , Acetamides/adverse effects , Acetamides/pharmacokinetics , Administration, Oral , Adult , Anti-Ulcer Agents/administration & dosage , Anti-Ulcer Agents/adverse effects , Anti-Ulcer Agents/pharmacokinetics , Area Under Curve , Asian People , Cross-Over Studies , Dose-Response Relationship, Drug , Drug Monitoring , Female , Food-Drug Interactions , Healthy Volunteers , Humans , Male , Piperidines/administration & dosage , Piperidines/adverse effects , Piperidines/pharmacokinetics , Pyridines/administration & dosage , Pyridines/adverse effects , Pyridines/pharmacokinetics , Stomach Ulcer/drug therapy , Tablets , Tandem Mass Spectrometry
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