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Background and Aims: Soil microorganisms play a crucial role in promoting growth and development, nutrient absorption, and disease resistance in poplar plantations. Long-term planting decays soil nutrient contents and changes the microfloral structure, and pathogenic microorganisms accumulate. It is of great significance to clarify the distribution and synergistic relationships between beneficial and pathogenic microorganisms in plantation soil for solving the long-term planting obstacles of poplar plantation. Methods: High-throughput sequencing, culture, pure bacterial identification, functional verification, and bioinformatics methods were used to explore the population and functional characteristics of the soil microorganisms in the perennial poplar forest, identify the main pathogenic and beneficial microorganisms in the soil, and investigate the synergistic relationships among the microorganisms in the system. Results: An evaluation of soil from a perennial poplar plantation revealed the presence of many beneficial microbes, such as Bacillus, Sphingomonas, Variovorax, and Streptomyces, as well as pathogenic microorganisms, including Fusarium and Alternaria. Most of these microorganisms were enriched in the rhizosphere soil. The study found that phosphorus was the driving factor affecting soil microorganisms, with available phosphorus (K = 0.189) and pH value (K = 0.113) significantly affecting fungal phylogeny. Bacterial community assembly processes were deterministic (βNTI < − 2), while those of fungi were stochastic (− 1 > βNTI > − 2). The microbial network in the rhizosphere was more stable than that in the bulk soil. This study expands our knowledge of the functional microbial germplasm resources of forest plantations and provides a theoretical basis for soil remediation in perennial poplar plantations. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A strategy for toughening phthalonitrile-based resin containing benzoxazine (BA-Ph) with poly (aryl ether nitrile) (PP-PEN) was proposed. Through kinetic analysis, the underlying influence mechanism of PP-PEN with different molecular weight on the polymerization process and cross-linking structure of BA-Ph was explored. In addition, the glass fiber reinforced composite laminates (BA-Ph/PP-PEN/GF) were fabricated by hot pressing. The effect of the molecular weight of PP-PEN on the mechanical and thermal properties of BA-Ph/PP-PEN/GF was verified. The results indicated that the impact strength of the modified composite laminates increased from 77 kJ/m2 to 106 kJ/m2. The bending strength and modulus improved from 484 to 516 MPa and 21 GPa to 25 GPa, respectively. Besides, all the thermal performances of the modified composite laminates had fairly good thermal stability (358 ~ 382 °C). It is believed that the as-prepared phthalonitrile-based composite material with high temperature resistance and toughness is expected to expand the application of high-performance resin based composites. [ABSTRACT FROM AUTHOR]

The effect of Al2O3 and MCNT nanoparticles on the crystallization behaviors, subsequent melting phenomenon, microstructures and mechanical performances of PEEN-based nanocomposites was first investigated and reported. It was found that the absence of nucleating role of Al2O3 made PEEN/Al2O3 nanocomposites show similar melting/cold crystallization and corresponding melting behaviors as those of PEEN matrix. By contrast, MCNT could play two different and competing roles in the crystallization process: acting as nucleating agents and constraining the mobility of polymer chains to hinder crystal growth. Consequently, PEEN/MCNT nanocomposites exhibit the increased Tc, but the decreased Wc, and double Tms. Heat treatment at 220 °C for 2 h turned to be an effective way to finish the cold crystallization process for PEEN and their nanocomposites. SEM images showed that spherical crystallite clusters could be clearly observed in PEEN and PEEN/Al2O3 nanocomposite, which were in well agreement with the DSC and WXRD results. The higher Wc of PEEN/Al2O3 nanocomposites also led to better impact and flexural strength than those of PEEN/MCNT nanocomposite. This research is expected to help us understand the crystallization behaviors and final properties of PEEN-based materials influenced with these two different dimensional nanoparticles. [ABSTRACT FROM AUTHOR]

The thermal conductive cyanate ester/epoxy (CE/AG80) composites with hexagonal boron nitride (h-BN) reinforced were manufactured and investigated. The low and stable dielectric constant/loss of the composites with respect to both frequency (500 Hz-100 kHz) and temperature (50-350 °C) were discussed as functions of the content of h-BN. It was found that the low and stable dielectric constant/ loss of the composites can be maintained in the whole frequency range at room temperature, and the mutations of constant/loss at the frequency of 1 kHz occurred above 280 °C for all of the samples. Moreover, a remarkable enhancement of the thermal conductivity (0.54 W/mK a 1.8-fold enhancement) was achieved with the introduction of h-BN and significantly outperformed traditional thermal conductive fillers. The significant improvements of the thermal conductivity of the composites were analyzed by the Agari’s model and the parameters of C1 and C2 were also calculated. [ABSTRACT FROM AUTHOR]

Two kinds of polyarylene ether nitriles (PEN) with different molecular structures were designed and synthesized by two kinds of bisphenol monomers. Then, solution casting method has been used to obtain three kinds of films based on the two kinds of pure PEN and their blends with a weight ratio of 1:1. The chemical structures of PEN were characterized by Fourier transform infrared (FTIR). Dynamic rheology behaviors were investigated to study the effects of inherent structures on the motion of molecular chains. Then, three kinds of foamed PEN films were prepared with supercritical carbon dioxide foaming method and the micro-morphology were monitored by scanning electron microscopy (SEM). Results indicated that microcellular foam films were obtained and dielectric properties of the foamed PEN films exhibited significant difference from that of un-foamed films. The dielectric constant of micro-foamed film decreased to 2.0. Moreover, the unusual dielectric properties of two kinds of PEN composite film were discussed in detail, which can be ascribed to the fact of micro-phase separation. [ABSTRACT FROM AUTHOR]

A novel sandwich-type CNTs/FeO/RGO composite with FeO as a bridge was successfully prepared through a simple solvent-thermal and ultrasonic method. The structure and morphology of the composite have been characterized by Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. This new structure can effectively prevent the agglomeration of GO and the combination of CNTs/FeO and RGO shows a strong reflection loss (R) (−50 dB) at 8.7 GHz with absorber thickness of 2.5 mm. Moreover, compared with CNTs/FeO/GO composite, it is found that the thermal treating process is beneficial to enhance the microwave absorption properties, which may be attributed to high conductivity of RGO. On this basis, the microwave absorbing mechanism is systematically discussed. All the data show that the CNTs/FeO/RGO composite exhibits excellent microwave absorption properties with light density and is expected to have potential applications in microwave absorption. [ABSTRACT FROM AUTHOR]

Conjugated amino-phthalocyanine copper containing carboxyl groups/magnetite (NH-CuPc@FeO) has been fabricated from FeCl·6HO and NH-CuPc via a simple solvothermal method and its electromagnetic properties investigated. Scanning electron microscopy and transmission electron microscopy revealed that the NH-CuPc@FeO was a waxberry-like nanomaterial with NH-CuPc molecules effectively embedded in the interior of FeO particles in the form of beads. Introduction of NH-CuPc effectively improved the complementarity between the dielectric and magnetic losses of the system, resulting in excellent electromagnetic performance. The minimum reflection loss of the as-prepared composite reached −33.4 dB at 7.0 GHz for coating layer thickness of 4.0 mm and bandwidth below −10.0 dB (90% absorption) of up to 3.8 GHz. These results indicate that introduction of NH-CuPc results in a composite with potential for use as an electromagnetic microwave absorption material. [ABSTRACT FROM AUTHOR]

To improve the dimensional stability and methanol resistance, a novel phthalonitrile-terminated sulfonated poly(arylene ether nitrile)s (SPENs) to prepare cross-linked membranes for direct methanol fuel cells (DMFCs) application has been successfully implemented. Compared with SPENs, cross-linked membranes exhibited lower water uptake, swelling ratio, and methanol permeability coefficient. For example, the water uptake and swelling ratio of SPEN-70 were 50.3 wt.% and 17.0% as the values of cross-linked sulfonated poly(arylene ether nitrile)s (CSPEN)-70 were merely 15.4 wt.% and 3.2% at 20 °C. The methanol permeability of SPEN-70 was 6.7 × 10 cm s as the values of CSPEN-70 were merely 1.4 × 10 cm s, which were all much lower than that of Nafion 117 (1.41 × 10 cm s) as expected. Although the proton conductivity of CSPEN slightly decreased by the introduction of cross-linked structure, it possessed higher selectivity than the SPEN and Nafion 117 due to their lower methanol permeability. The cross-linked SPEN-50 (CSPEN-50) membrane exhibited the highest selectivity, which about 30.7 times higher compared with that of Nafion 117. [ABSTRACT FROM AUTHOR]

In order to reduce water uptake, swelling ratio, and methanol permeability in sulfonated proton exchange membranes (PEM), novel-sulfonated aromatic poly(ether ether nitrile)s-bearing pendant propenyl groups had been synthesized by direct copolymerization method. All the results showed that the propenyl groups were suitable cross-linkable groups, and that this method was an effective way to overcome the drawbacks of sulfonated polymers at high ion exchange capacity (IEC) values. By cross-linking, the water uptake, swelling ratio, and methanol diffusion could be restricted owing to the formation of compact network structure. For example, CSPEN-60 membranes showed the proton conductivity of 0.072 S cm at 80 °C, while the swelling ratios and water uptake (17.9 and 60.7 %) were much lower than that of the SPEN-60 membrane (60.8 and 295.2 %). Meanwhile, a 1.1 × 10 cm s of methanol diffusion was obtained which was much lower than that of Nafion 117 (14.1 × 10 cm s). Although the proton conductivity of the CSPEN-60 membranes is lower than that of the SPEN-60 membrane, the selectivity is much higher. The CSPEN-60 membrane exhibited the highest selectivity among the tested membranes, about 5.8 times higher compared with that of Nafion117. [ABSTRACT FROM AUTHOR]

Background: Rufinamide is a triazole derivative that is structurally unrelated to currently marketed antiepileptic medications for add-on treatment of seizures in the setting of Lennox-Gastaut syndrome in patients from the age of 4 years. Objective: The purpose of this study was to determine the pharmacokinetic and safety profile of single and multiple doses of rufinamide in healthy Chinese subjects. The effects of food and gender on the pharmacokinetic properties of rufinamide were also evaluated. Methods: In the single-dose study, volunteers were randomly assigned to 4 dose groups and received a single dose of 200, 400, 800, 1200 mg rufinamide tablets under fasting condition. Ten subjects in the 200-mg dose group were randomly assigned to either a high-fat or non-high-fat breakfast group in each study period. The drug administration was separated by a washout period of 7 calendar days. In the multiple-dose study, 10 subjects were administered on an empty stomach rufinamide 200 mg twice daily for 6 consecutive days. Liquid chromatography tandem mass spectrometry (LC-MS/MS) method was applied to determine plasma concentration of rufinamide. Pharmacokinetic parameters, including the maximum plasma concentration ( C ), the time to peak concentration ( t ), the area under the plasma concentration versus time curve from time 0 to the last measurable concentration (AUC) and from time 0 to infinity (AUC), terminal elimination half-life ( t ), apparent volume of distribution ( V ), apparent clearance (CL), average residence time (MRT), area under the plasma concentration versus time curve from time 0 to the last measurable concentration at steady state (AUC), peak concentration ( C ) and trough level concentration ( C ) at steady state were calculated using non-compartmental models. Tolerability was assessed based on investigator inquiries, spontaneous reports and clinical evaluations. Results: Rufinamide displayed a dose-dependent, but sub-proportional increase in exposure following single-dose and repeated dose administration. After administration of single dose of 200, 400, 800 and 1200 mg, without food, the rufinamide mean C (standard deviation, SD) was 1806.5 (526.4), 2490 (564.8), 3719 (976.1) and 4166 (1187.1) μg/L, respectively. Mean AUC (SD) was 34,571 (9484), 56,246 (18,077), 89,022 (23,379) and 107,316 (34,766) μg·h/L, respectively. While in fed condition at the dosage of 200 mg, mean C (SD) and mean AUC (SD) were 2363 (582) μg/L and 40,593 (10,516) μg·h/L, respectively. After administration of multiple doses, arithmetic mean (SD) values of C and AUC were 3566 (873) μg/L and 62,803 (19,873) μg·h/L, respectively. The steady state was achieved by day 3 of multiple dosing after 2 daily doses (twice a day), the corresponding accumulation factor (AUC/AUC) was 0.9057. Although there were no substantial effects on exposure resulting from gender differences, a notable food effect was observed, with AUC and C increased by 17.4 and 30.8 %, respectively. Single- and multiple-dose phases were generally safe and well tolerated. Conclusion: Overall, 15 % (6/40) of subjects experienced a mild indisposition with no serious adverse events. On single and multiple dosing, rufinamide exhibited nonlinear pharmacokinetics and was well tolerated in healthy Chinese subjects. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Allyl-functional phthalonitrile monomer (DBPA-Ph) was blended with the phthalonitrile containing benzoxazine (BPNBZ) to achieve good processing property with low curing viscosity. The processing behavior of BPNBZ/DBPA-Ph system was studied by differential scanning calorimetric analysis (DSC) and dynamic rheological analysis. The result indicated that the BPNBZ/DBPA-Ph system exhibited relatively low viscosity, good reactivity and processing property. The similar thermal and thermo- stabilities of DBPA-Ph and BPNBZ polymer endued the BPNBZ/DBPA-Ph system stable thermal ( T ≥ 437 °C) and thermo- stabilities ( T ≥ 449 °C) with the change of BPNBZ content. Compared with the poor mechanical property of pure DBPA-Ph/GF composites, the introduction of BPNBZ enhanced the mechanical property of BPNBZ/DBPA-Ph/GF composites distinctly, especially at low curing temperature. Therefore, the low viscosity, good polymerization property, stable thermal and thermo- stabilities and improved mechanical property indicated wider application for DBPA-Ph polymer. [ABSTRACT FROM AUTHOR]

Nitrile functionalized AlO (AlO-CN) particles were employed to reinforce polyarylene ether nitriles terminated with phthalonitrile (PEN- t-CN) polymer. The composites were prepared via hot pressure casting technique in the form of a sheet. To improve the interfacial compatibility between polymer matrix and AlO, AlO was nitrile functionalized by bisphthalonitrile (BPH) previously and confirmed by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). The micromorphology, thermal, mechanical and dielectric properties of AlO-CN/PEN- t-CN composites were systematically investigated. The AlO/PEN- t-CN composite with 5 wt% raw AlO was prepared for comparison. SEM observations indicated that the AlO-CN particles exhibited rough surface which resulted in favorable interfacial compatibility with PEN- t-CN polymer matrix. DSC curves revealed that the glass transition temperature ( T) of the AlO-CN/PEN- t-CN composites were in the range of 178 to 185 °C, indicating that all the composites exhibited high working temperature. The results of TGA indicated that the AlO-CN/PEN- t-CN composites showed excellent thermal stabilities with initial degradation temperature ( T) up to 491 °C in N atmosphere. The tensile strength increased from 93.51 MPa for AlO/PEN- t-CN composite to 97.91 MPa for AlO-CN/PEN- t-CN composite with 15 wt% AlO-CN loading. It was also observed that the dielectric constant of composites increased regularly with increasing the content of AlO-CN and the dielectric loss exhibited little dependence on frequency. In sum, excellent mechanical properties combined with good operating temperature of the AlO-CN/PEN- t-CN composites would lead to particularly attractive for practical applications in aerospace, automotive, and industrial fields. [ABSTRACT FROM AUTHOR]

Self-promoted copolymerization behavior and processability of phthalonitrile oligomer/phthalonitrile containing benzoxazine (Po/BA-ph) system were investigated by differential scanning calorimetry and dynamic rheological analysis. The results revealed that Po/BA-ph systems exhibited double-stage curing behaviors which corresponded to the ring-opening polymerization of benzoxazine rings and ring-formation polymerization of nitrile groups. Compared with Po, processability of Po/BA-ph blends was improved and could be tuned by varying BA-ph contents, processing temperature, and time. The structures of the copolymers were also characterized and discussed to further confirm the copolymerizing behaviors. Then Po/BA-ph copolymers were employed to prepare Po/BA-ph/glass fiber (GF) composite laminates, and their mechanical and thermal properties were investigated. Compared with those of Po/GF composites, the flexural strength and modulus of Po/BA-ph/GF composites were increased by 6.5 and 25 %, respectively. All of the Po/BA-ph/GF composite laminates were stable up to 430 °C in air. The systematic study of Po/BA-ph system could enrich the thermosetting resin/thermosetting resin systems in industrial applications. Meanwhile, the outstanding mechanical properties and thermal stabilities enable the Po/BA-ph/GF composite laminates to be further applied in the areas which require excellent mechanical properties and high temperature resistance. [ABSTRACT FROM AUTHOR]

An aromatic, diether-linked phthalocyanine resin (Pc) was prepared from 4,4′-bis (3,4-dicyanophenoxy) biphenyl (BPh) and investigated for morphology, microstructure, dielectric, conductivity and microwave absorption properties at different annealing temperatures from 300 to 800 °C. The results showed that the annealing temperature could significantly change the morphology and microstructure of the Pc polymer, leading to the generation of carbon-Pc polymer composites, and enhance the microwave absorbing and electrical properties of the Pc polymer. The dramatic electrical and dielectric transition happened when the annealing condition was 550 °C 24 h. The conductivity of the samples exhibited a transition of electrical behavior from an insulator to semiconductor of approximately 10 S/cm. Pc polymer exhibited excellent microwave absorption properties in the frequency range of 0.5-18.0 GHz after sintering process. The microwave absorption of the annealing Pc polymer can be mainly attributed to the dielectric loss rather than magnetic loss. The sample annealed at 500 °C 24 h had two strong microwave absorbing peaks and achieved a maximum absorbing value of −44 dB around 10.7 and 17.5 GHz when the thickness was 3.0 mm. The novel carbon-Pc polymer composites were believed to have potential applications in the microwave absorbing area. [ABSTRACT FROM AUTHOR]

A novel kind of organic-inorganic hybrid magnetic composites was prepared via in situ polymerization between FeO/iron phthalocyanine oligomer (FeO/FePc) hybrid microspheres and phthalocyanine (Pc) prepolymers in the presence of aromatic amine (3-APN). The FeO/FePc hybrid microspheres exhibited loose interpenetrating network structures with diameters of 180 ± 20 nm. Magnetic properties of final FeO/FePc/Pc composites investigated by the vibrating sample magnetometer (VSM) indicated that the magnetic composites possessed considerable increased magnetism with the increase of FeO/FePc content. The saturation magnetization of the magnetic composites with 15 wt.% content of FeO/FePc was 3.500 emu/g (1,590 % increase) in comparison with that of composites with 5 wt.% FeO/FePc content. Mechanical and thermal properties of the magnetic composites were also investigated. The flexural strength and modulus increase from 53.8 MPa and 3.47GPa in Pc composite to 70.4 MPa and 4.18GPa in FeO/FePc/Pc composite with 15 wt.% FeO/FePc content, leading to 30.8 % and 20.4 % increase respectively. The mechanical enhancements can be largely attributed to the good dispersion and finer compatibility of FeO/FePc hybrid microspheres and Pc matrices, which were confirmed by SEM. Additionally, all the magnetic composites obtained demonstrated excellent thermal stability up to 550 °C in air. Thus the FeO/FePc/Pc magnetic composites with considerable magnetic properties as well as outstanding mechanical properties and excellent thermal stabilities can be used in advanced functional and structural materials. [ABSTRACT FROM AUTHOR]

Multi-wall carbon nanotubes reinforced thermoset phthalocyanine (Pc/CNTs) nanocomposites were successfully prepared through melt-mixing and masterbatch dilution and investigated for their morphologies and physical properties. Pc/CNTs nanocomposites were prepared by the more optimized masterbatch method. The feasibility of using Pc/CNTs nanocomposites was investigated by evaluating their electrical, dielectric, mechanical, morphological and thermal properties as a function of CNT loading. Consequently, the dramatic electrical and dielectric transition happened when CNT content was about 1 wt%. For the 1 wt% CNTs-filled Pc nanocomposites, a 51.4 % increase in flexural strength was obtained and flexural modulus was also improved from 3851.7 MPa to 3973.3 MPa. All Pc/CNTs nanocomposites showed high thermal and thermo-oxidative stabilities up to 535 °C. Pc/CNTs nanocomposites with multifunctional properties can find uses under some critical circumstances with requirements of high strength and temperature. [ABSTRACT FROM AUTHOR]

A facile production of multiwalled carbon nanotubes (MCNTs) using iron-phthalocyanine polymer as the only carbon source with two kinds of metallic catalysts (Fe(CO) and nano-iron) has been compared here. SEM, TEM and XRD were employed to figure the detailed structures of the carbon nanotubes. Consequently, catalyst played a key role in the formation of MCNTs: nano-iron resulted in iron-filled CNTs while Fe(CO) led to empty CNTs. Both of these two CNTs were long and straight, with ~100 nm in diameter and several tens of micrometers in length. Moreover, dielectric and magnetic properties were carried to further study synthesized carbon nanotubes. The results showed that the empty MCNTs had better dielectric properties than iron-filled MCNTs although the iron-filled CNTs exhibited the magnetic saturation of ~3.5 emu/g and coercive force of ~594.0 Oe, which is much higher than empty MCNTs. [ABSTRACT FROM AUTHOR]

Hashimoto’s thyroiditis is the archetype of organ-specific autoimmune disease. The key pathogenetic feature is the activation of thyroid-specific T-cells by properly presented endogenous thyroid antigens. There is strong indication that thyrocytes themselves present self-antigens, based on the finding of antigen presenting human leukocyte antigen-DR (HLA-DR) molecules on the thyrocytes in Hashimoto’s thyroiditis. Because class II-associated invariant chain (li) is tightly bound to the antigen-binding groove of the DR molecules in the endoplasmic reticulum and is found to compete with the endogenous peptides for binding with DR, it is speculated that li prevents endogenous peptides from binding to, and being presented by, DR on the cell surface. We hypothesize that in Hashimoto’s thyroiditis, Ii is insufficient, leaving DR molecules open for endogenous peptides. In this article, we test our hypothesis of discordance between DR and li in the thyroid epithelial cells in Hashimoto’s thyroiditis by immunohistochemistry. Formalin-fixed, paraffin-embedded archival tissue from eight cases of Hashimoto’s thyroiditis and four cases of normal thyroid specimen were randomly selected and immunostained with monoclonal antibodies (MAbs) against HLA-DR and li using avidin-biotin-peroxidase method. We found that in all eight cases of Hashimoto’s thyroiditis, li is significantly reduced relative to DR. The results support our hypothesis that presentation of self-antigen may be a result of insufficient li in the thyrocytes in Hashimoto’s thyroiditis. [ABSTRACT FROM AUTHOR]