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Taking the carbon family as an example, this paper introduces the teaching design and practice for incorporating ideological and political education into chemistry of elements. Frontiers of science and technology, materialist dialectics and scientific epistemology, patriotism, ecological civilization thought, China's "double carbon" story in the new era, history of discovery of elements, scientific ethics and morality, etc. were aptly incorporated into the links of content setting and classroom teaching aiming at cultivating students' spirit of the craftsman, scientific thinking, patriotism, ecological civilization thought, exploration spirit, and professional ethics. Simultaneous promotion of "knowledge transfer" and "value guidance" was realized. [ABSTRACT FROM AUTHOR]

We compare static and dynamic properties obtained from three levels of modeling for molecular dynamics simulation of poly(ethylene oxide) (PEO). Neutron scattering data are used as a test of each model’s accuracy. The three simulation models are an explicit atom (EA) model (all the hydrogens are taken into account explicitly), a united atom (UA) model (CH2 and CH3 groups are considered as a single unit), and a coarse-grained (CG) model (six united atoms are taken as one bead). All three models accurately describe the PEO static structure factor as measured by neutron diffraction. Dynamics are assessed by comparison to neutron time of flight data, which follow self-motion of protons. Hydrogen atom motion from the EA model and carbon/oxygen atom motion from the UA model closely follow the experimental hydrogen motion, while hydrogen atoms reinserted in the UA model are too fast. The EA and UA models provide a good description of the orientation properties of C–H vectors measured by nuclear magnetic resonance experiments. Although dynamic observables in the CG model are in excellent agreement with their united atom counterparts, they cannot be compared to neutron data because the time after which the CG model is valid is greater than the neutron decay times. [ABSTRACT FROM AUTHOR]

Lyocell fiber has emerged as an important class of regenerated cellulose that is produced based on the N-methyl morpholine-N-oxide (NMMO) dissolution method, and it has unique properties compared to viscose fiber. The NMMO technology provides a simple, resource-conserving, and environmentally friendly method for producing regenerated cellulose fiber. In this paper, the manufacturing process, environmental impact, and product quality of lyocell fiber are reviewed and compared with those of the conventional viscose fiber. [ABSTRACT FROM AUTHOR]

The increasing consumption of regenerated cellulose, in particular the viscose fiber, has led to a significant development of dissolving pulps in the last decade. In this review paper, the current status of dissolving pulp with respects to raw materials, manufacturing processes, and some key issues are discussed. Non-wood materials and the process concept of upgrading paper-grade pulp into dissolving pulp are also included. Some recent developments related to the analytical methods of the purity and molecular weight distribution based on the ion chromatography and gel permeation chromatography are discussed. Finally, further processing improvements of purification, such as mechanical, chemical, and enzymatic treatment, and their combinations during the manufacturing process of dissolving pulp, are included. [ABSTRACT FROM AUTHOR]

Background/Aims: In this study, we examined whether the combination of hyperbaric oxygen (HBO) and diltiazem therapy provided a cardioprotective effect on myocardial ischemia-reperfusion injury (MIRI) rat model. Methods: Sixty healthy Sprague-Dawley rats were randomly divided into sham, IR, diltiazem (5 mg/kg), HBO (0.25 MPa, 60 min) and combination therapy (HBO plus diltiazem) groups. MIRI model was established by ligating the left anterior descending for 30 min, followed by 60 min of reperfusion. Results: The results show that HBO and diltiazem preconditioning significantly improves cardiac function and myocardial infarction area, increases nitric oxide, endothelial nitric oxide synthase and ATPase (Na+-K+-ATPase and Ca2+-Mg2+-ATPase) activity and decreases levels of oxygen stress, myocardial enzymes and endothelin-1. Notably, HBO and diltiazem preconditioning significantly increased Bcl-2 protein expression and decreased Bax protein and caspase-3 mRNA expression. Conclusions: These data indicate that combination therapy protected against heart MIRI by reducing oxygen stress damage, correcting energy metabolism, improving endothelial function and inhibiting cell apoptosis. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed direct arylation of 2-arylimidazo[1,2- a]pyridines with o-dihaloarenes via double C-H activation is described. The process comprises intermolecular C3-arylation of 2-arylimidazo[ 1,2-a]pyridines followed by an intramolecular C5-arylation in a highly regioselective fashion, affording benzo[a]imidazo[5,1,2-cd]indolizine derivatives in moderate to good yields. [ABSTRACT FROM AUTHOR]

A straightforward method has been developed for the synthesis of the benzimidazole ring system through a carbon-nitrogen cross-coupling reaction. In the presence of 2.0 equiv. of K2CO3 in water at 100 °C for 30 h, the intramolecular cyclization of N-(2-iodoaryl)benzamidine provides benzimidazole derivatives in moderate to high yields. Remarkably, the procedure occurs exclusively in water and doesn't require the use of any additional reagent/catalyst, rendering the methodology highly valuable from both environmental and economical points of view [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: Arisaema rhizomatum C.E.C. Fischer (ARCF), called as “Xuelijian”, a local herb just growing in China, has been used as a traditional ethnic Chinese medicine for long because of its remarkable activity to alleviate pain and inflammation for patients suffering from rheumatism among the people with weak side-effect. However, rare study on the anti-arthritic activity of ARCF has been reported in vivo. The aim of this study is to investigate the protective effect of the herb on collagen-induced arthritis in mice and explore the potential immunological mechanisms. Materials and methods: CIA was induced in male BALB/c mice by been subcutaneously injected type II bovine collagen (CII) for twice. The combined MeOH extract (ME) of ARCF rhizome was successively partitioned into four fractions with petroleum ether (PE), ethyl acetate (EE), n-butyl alcohol (n-BE) and water (WE). After the second collagen immunization, mice were administered orally with different doses of ME, EE and n-BE (ME 130, 261, 522mgkg−1; EE 10.2, 20.4, 40.8mgkg−1; n-BE 52, 104, 208mgkg−1) every other day for 3 weeks. The progression of edema of paws and knee joints was inspected by using a vernier calliper every 3 days from the 10th day after the first injection to the end of the experiment. The spleen index was measured and the knee joint destruction was observed by pathological sections. Levels of inflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-33 (IL-33 or IL-1F11) and rheumatoid factor (RF) in serum were measured by ELISA. Results: Administration of ME, EE and n-BE significantly suppressed paws and joints swelling and reduced the spleen indexes. Pathological examination demonstrated that ARCF effectively protected anklebone and cartilage from being eroded versus vehicle-treated mice. Moreover, the serum levels of inflammatory cytokines TNF-α, IL-1β, IL-6, IL-33 and RF were markedly lowered in ARCF treated groups compared with the control group (p <0.05). Conclusion: Our studies demonstrate that administration of ARCF is obviously suppressed the progression of CIA. The anti-arthritic effectiveness of ARCF will make the herb a strong candidate for further clinical trials on RA patients. [Copyright &y& Elsevier]

CD4+ T cells can be instructed by nonantigen-specific signals to differentiate into functionally distinct lineages with mutually exclusive patterns of cytokine production. The molecular events that drive interferon-γ (IFNγ) production during Th1 development are well understood, but mechanisms that silence this cytokine during Th2 polarization are not clear. In this study, we find that the tbx21 gene encoding the Th1 master regulator T-bet is a direct target of the transcriptional repressor Ikaros. In Th2 cells, which do not express T-bet, strong Ikaros binding could be detected at the endogenous tbx21 promoter, whereas this gene was not occupied by Ikaros in T-bet-expressing Th1 cells. Inhibition of Ikaros DNA binding activity during Th2 polarization resulted in loss of Ikaros promoter occupancy, increased T-bet expression, and inappropriate T-bet-dependent production of IFNγ. Ikaros was also required for epigenetic imprinting of the ifn? locus during Th2 polarization, and loss of Ikaros function in vivo led to an inappropriate Th1 response to the parasite Shistosoma mansoni. These studies demonstrate that Ikaros, a factor with an established role in lymphocyte development, also regulates the development of peripheral T helper responses. [ABSTRACT FROM AUTHOR]

A series of hydrotalcite-like compounds were prepared under microwave irradiation, which were used to catalyze the Baeyer–Villiger oxidation of cyclohexanone to ε-caprolactone with hydrogen peroxide as oxidant. The results show that stibium-containing hydrotalcite (Sb-HTL) has good catalytic properties in the reaction. In the Baeyer–Villiger oxidation of cyclohexanone to ε-caprolactone with H2O2 catalyzed by Sb-HTL, the effects of reaction time, reaction temperature, amount of catalyst and H2O2/cyclohexanone molar ratio are also investigated in details. It is shown the cyclohexanone conversion and ε-caprolactone selectivity can reach 79.15 and 93.84%, respectively, under the optimum reaction conditions. Furthermore, Sb-HTL can be reused for six times without obvious loss of activity and selectivity. Therefore, Sb-HTL is reusable and would be a promising catalyst for the Baeyer–Villiger oxidation using green and cheap oxidants like hydrogen peroxide instead of peroxycarboxylic acids. [ABSTRACT FROM AUTHOR]

We use explicit atom molecular dynamics to investigate mobility in poly(methyl methacrylate) [PMMA] when blended with 10%, 20%, and 30% weight percent poly(ethylene oxide) [PEO]. The responses to blending of main chain motion, rotation of the two methyl groups, and rotation of the entire ester side chain, which is associated with the β-relaxation, are individually assessed at temperatures well above the glass transition temperature where their characteristic times overlap. We also consider the response of main chain motion in PEO to blending with PMMA. We find three classes of behavior: methyl group rotation is not influenced by blending, ester group rotation and the main chain motion of PEO are slightly altered by the change in environment, and a substantial change in dynamics is observed for main chain motion in PMMA. The observation that the β-relaxation in PMMA changes with mixing is unusual, as this is a local motion thought to be insensitive to blending. This is discussed in light of the spatial extent of localized motion and that of mixing of the two components. [ABSTRACT FROM AUTHOR]

We use molecular simulation to compare component dynamics of a poly(ethylene oxide) [PEO] and poly(methyl methacrylate) [PMMA] blend with that of a diblock copolymer of the same overall composition. The blend and the copolymer have different intermolecular packing, which leads to a difference in compositions defined over local length scales. These “effective concentrations” directly impact dynamic behavior through the chain connectivity model for blend dynamics, which is based on a single controlling length scale for dynamics equal to the Kuhn length. By comparing the change in dynamics expected on the basis of different effective concentrations with the actual change observed in the simulations, we find that this idea is quantitatively accurate for the PMMA component. For PEO, the controlling length scale for dynamics varies with the size of the observation volume. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Treg) express Foxp3, a forkhead family member that is necessary and sufficient for Treg lineage choice and function. Ectopic expression of Foxp3 in non-Treg leads to repression of the interleukin 2 (IL-2) and interferon γ (IFNγ) genes, gain of suppressor function, and induction of genes such as CD25, GITR, and CTLA-4, but the mode by which Foxp3 enforces this program is unclear. Using chromatin immunoprecipitation, we have demonstrated that Foxp3 binds to the endogenous IL-2 and IFNγ loci in T cells, but only after T cell receptor stimulation. This activation-induced Foxp3 binding was abrogated by cyclosporin A, suggesting a role for the phosphatase calcineurin in Foxp3 function. We have also shown that binding of Foxp3 to the IL-2 and IFNγ genes induces active deacetylation of histone H3, a process that inhibits chromatin remodeling and opposes gene transcription. Conversely, binding of Foxp3 to the GITR, CD25, and CTLA-4 genes results in increased histone acetylation. These data indicate that Foxp3 may regulate transcription through direct chromatin remodeling and show that Foxp3 function is influenced by signals from the TCR. [ABSTRACT FROM AUTHOR]

We have constructed a bimetallic (CoNiP) nanozyme, leveraging the synergistic effect of cobalt and nickel, which efficiently catalyzes the oxidation of TMB from colorless to ox-TMB (blue). Density functional theory (DFT) calculations further highlight the pivotal role of this synergistic effect in improving the adsorption energy of oxygen intermediates, accelerating the catalytic process. [ABSTRACT FROM AUTHOR]

Effective separation of cellulose and hemicellulose from lignocellulosic biomass is an essential step for creating high-value products. In this study, a modified treatment process was proposed for cellulose purification via microwave-assisted formic acid catalytic hydrolysis followed by cold caustic extraction. The sugar content in the extract was determined using UV spectrophotometer and dual-wavelength visible spectrophotometry. Combined microwave-assisted formic acid (M-FA) with cold caustic extraction (CCE) treatments achieved rapid separation and removal of hemicelluloses from waste hardwood pulp fibers. The hemicelluloses content decreased from 28.6% to 2.3%, and the lignin content changed from 27.8% to 6.1%, which resulted in a maximal cellulose content of 91.5% under the optimal M-FA/CCE treatment conditions. In addition, the crystallinity index of pulp fibers increased from 54.3% to 67.1%, and the initial decomposition temperature decreased from 335.4 to 270.2 °C with the decrease of hemicellulose and lignin content. The modified process provided a sustainable and effective method for hemicellulose separation and lignin removal from cellulosic fibers. [ABSTRACT FROM AUTHOR]

A convenient approach has been developed for the construction of quinolin-4(1H)-one frameworks, starting from (Z)-β-chlorovinyl aromatic ketones and amines. Intermolecular Michael addition of an amine to a (Z)-β-chlorovinyl ketone was followed by elimination of a chloride anion to give enamine intermediates, with full retention of the initial Z-configuration. The enamine intermediates were transformed into quinolin-4(1H)-one products by a palladium-catalyzed intramolecular N-arylation in a tandem one-pot manner, with good to excellent yields. [ABSTRACT FROM AUTHOR]

Background The objective of this study is to describe the system and technical factors that enabled our moderate size transhiatal esophagectomy program to achieve low mortality rates. Methods A retrospective chart review was conducted on 200 consecutive patients who underwent transhiatal esophagectomy at Robert Wood Johnson University Hospital. Primary outcomes included operative times, estimated blood loss, frequency and nature of complications, and lengths of stay in the hospital and the intensive care unit. Results In general, surgical outcomes tended to improve over the course of this study. We identified decreased operative time, intra-operative blood loss, frequency of complications, and lengths of intensive care unit and hospital stay as the program matured. Through coordinated actions of the surgical and anesthesia teams, all intraoperative injuries were responded to in an effective, emergent fashion and all but one patient was saved. This resulted in an inhospital and 30-day mortality rate of only 0.5%. Conclusions Our study suggests that a dual attending approach, focus on avoiding "failure to rescue", increased volume, and a surgeon driven commitment to quality improvement may lead to low mortality rates after transhiatal esophagectomy. [ABSTRACT FROM AUTHOR]

An efficient "one-pot" route for the synthesis of benzo[4,5]imidazo[2,1-a] isoquinolines has been developed via nucleophilic addition of 2-aryl benzimidazoles to alkynyl bromides and subsequent palladium-catalyzed intramolecular C-H vinylation. [ABSTRACT FROM AUTHOR]

Salmonella Paratyphi A (S. Paratyphi A) is a highly adapted, human-specific pathogen that causes paratyphoid fever. Cases of paratyphoid fever have recently been increasing, and the disease is becoming a major public health concern, especially in Eastern and Southern Asia. To investigate the genomic variation and evolution of S. Paratyphi A, a pan-genomic analysis was performed on five newly sequenced S. Paratyphi A strains and two other reference strains. A whole genome comparison revealed that the seven genomes are collinear and that their organization is highly conserved. The high rate of substitutions in part of the core genome indicates that there are frequent homologous recombination events. Based on the changes in the pan-genome size and cluster number (both in the core functional genes and core pseudogenes), it can be inferred that the sharply increasing number of pseudogene clusters may have strong correlation with the inactivation of functional genes, and indicates that the S. Paratyphi A genome is being degraded. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed intramolecular C-H activation/C-C cross-coupling has been developed for a straightforward and efficient synthesis of phenanthridines. With Pd(OAc)2 (4 mol %) as the catalyst, PCy3 (8 mol %) as the ligand, and Cs2CO3 as the base, this protocol was applied to synthesize a small library of phenanthridine derivatives in good yields in THF. [ABSTRACT FROM AUTHOR]

Background: Atherosclerosis (AS) is a common cardiovascular disease. Transformation of macrophages to form foam cells by internalizing modified low density-lipoprotein (LDL) via scavenger receptor (SR) is a key pathogenic process in the onset of AS. It has been demonstrated that SR-PSOX functions as either a scavenger receptor for uptake of atherogenic lipoproteins and bacteria or a membrane-anchored chemokine for adhesion of macrophages and T-cells to the endothelium. Therefore, SR-PSOX plays an important role in the development of AS. In this study the key basic amino acids in the chemokine domain of SR-PSOX have been identified for its functions. Results: A cell model to study the functions of SR-PSOX was successfully established. Based on the cell model, a series of mutants of human SR-PSOX were constructed by replacing the single basic amino acid residue in the non-conservative region of the chemokine domain (arginine 62, arginine 78, histidine 80, arginine 82, histidine 85, lysine 105, lysine 119, histidine 123) with alanine (designated as R62A, R78A, H80A, R82A, H85A, K105A, K119A and H123A, respectively). Functional studies showed that the mutants with H80A, H85A, and K105A significantly increased the activities of oxLDL uptake and bacterial phagocytosis compared with the wild-type SR-PSOX. In addition, we have also found that mutagenesis of either of those amino acids strongly reduced the adhesive activity of SR-PSOX by using a highly non-overlapping set of basic amino acid residues. Conclusion: Our study demonstrates that basic amino acid residues in the non-conservative region of the chemokine domain of SR-PSOX are critical for its functions. Mutation of H80, H85, and K105 is responsible for increasing SR-PSOX binding with oxLDL and bacteria. All the basic amino acids in this region are important in the cells adhesion via SR-PSOX. These findings suggest that mutagenesis of the basic amino acids in the chemokine domain of SR-PSOX may contribute to atherogenesis. [ABSTRACT FROM AUTHOR]

A convenient and quick method has been developed for simultaneous detection of several low molecular weight chlorinated organic compounds (LMWC) in polyamideamine-epichlorohydrin (PAE) solution, using headspace-solid phase microextraction-gas chromatography (HS-SPME-GC). The method consists of extracting a sample containing 0.42 g/mL NaCl with an 85 µm polyacrylate (PA) coated fiber at an extraction temperature of 45°C, for an extraction time of 30 mins, and desorbing the analytes at 240°C for 6 mins. Under these optimized conditions, relatively low limits of detection (LOD) of the analytes, good linearity (r2 £ 0.9934) and precision (relative standard deviation (RSD ¢ 4.38%)) were obtained. Taking into account the matrix effect, standard addition methodology was applied to validate this method and recovery values were between 91.59% and 109.69%. This method is therefore well-suited for accurate determination of low levels of LMWC in PAE.

Multisubstituted indoles were synthesized via a one-pot tandem copper-catalyzed Ullmann-type C-N bond formation/intramolecular cross-dehydrogenative coupling process at 130 °C in DMSO. The methodology allows practical and modular assembly of indoles in good to excellent yields from readily available aryl iodides and enamines. [ABSTRACT FROM AUTHOR]

4-Quinolone and 4H-thiochromen-4-one derivatives are readily synthesized in a tandem one-pot manner in good to excellent yields. Starting from (Z)-β-chlorovinyl ketones, an intermolecular nucleophilic addition of amines or sodium hydrogen sulfide to (Z)-β-chlorovinyl ketones was followed by elimination of chlorine anion to give Z-enamine or thioenol intermediates, which can be transformed to 4-quinolone or 4H-thiochromen-4-one products through intramolecular SNAr reaction, respectively. [ABSTRACT FROM AUTHOR]

An efficient palladium-catalyzed protocol for the tandem synthesis of quinazolinone-fused phenanthridinones from 2-arylquinazolinones and o-dihaloarenes is described. This reaction sequence comprises direct intermolecular C-H arylation of 2-arylquinazolinones followed by an intramolecular aryl amidation reaction, affording 14H-quinazolino[3,2-f]phenanthridin-14-one derivatives in moderate to good yields. [ABSTRACT FROM AUTHOR]

Background: It has been well accepted that glycans present in schistosomes are highly antigenic. However, it is not clear what kind of worm glycans can affect the infected host to mount IgG responses and whether mounted anti-glycan IgG responses are protective. Methods: The contribution of antigenicity by glycans was measured by using competitive ELISA assay in sera from infected mice and humans. Monoclonal antibodies towards soluble Schistosoma japonicum egg antigens (SjEA) were generated from SjEA immunizated mice. The expression of glycans on surfaces of cercaria or young worm and their distributions were examined by immunofluorescence assay. The protective roles of glycans-specific mAbs were assayed by determination of the worm and egg burden in infected mice. Results: Both periodate-resistant glycans and periodate-sensitive glycans are antigenic in schistosome infections. When monoclonal antibodies against either periodate-sensitive or periodate-resistant glycans were administered prior to schistosome infections in mice, both kinds of anti-glycan antibodies were found to successfully provide protective immunity to infectedmice. Conclusions: Both periodate-resistant and periodate-sensitive glycans are antigenic, and dominant anti-glycan IgG responses can play important roles in protective immunity in schistosome infected hosts. [ABSTRACT FROM AUTHOR]

Background Thyroid nodules are present in 19%-67% of the population and carry a 5%-10% risk of malignancy. Unfortunately, fine-needle aspiration biopsies are indeterminate in 20%-30% of patients, often necessitating thyroid surgery for diagnosis. Numerous DNA microarray studies including a recently commercialized molecular classifier have helped to better distinguish benign from malignant thyroid nodules. Unfortunately, these assays often require probes for >100 genes, are expensive, and only available at a few laboratories. We sought to validate these DNA microarray assays at the protein level and determine whether simple and widely available immunohistochemical biomarkers alone could distinguish benign from malignant thyroid nodules. Methods A tissue microarray (TMA) composed of 26 follicular thyroid carcinomas (FTCs) and 53 follicular adenomas (FAs) from patients with indeterminate thyroid nodules was stained with 17 immunohistochemical biomarkers selected based on prior DNA microarray studies. Antibodies used included galectin 3, growth and differentiation factor 15, protein convertase 2, cluster of differentiation 44 (CD44), glutamic oxaloacetic transaminase 1 (GOT1), trefoil factor 3 (TFF3), Friedreich Ataxia gene (X123), fibroblast growth factor 13 (FGF13), carbonic anhydrase 4 (CA4), crystallin alpha-B (CRYAB), peptidylprolyl isomerase F (PPIF), asparagine synthase (ASNS), sodium channel, non-voltage gated, 1 alpha subunit (SCNN1A), frizzled homolog 1 (FZD1), tyrosine related protein 1 (TYRP1), E cadherin, type 1 (ECAD), and thyroid hormone receptor associated protein 220 (TRAP220). Of note, two of these biomarkers (GOT1 and CD44) are now used in the Afirma classifier assay. We chose to compare specifically FTC versus FA rather than include all histologic categories to create a more uniform immunohistochemical comparison. In addition, we have found that most papillary thyroid carcinoma could often be reasonably distinguished from benign disease by morphological cytology findings alone. Results Increased immunoreactivity of CRYAB was associated with thyroid malignancy (c-statistic, 0.644; negative predictive value [NPV], 0.90) and loss of immunoreactivity of CA4 was also associated with malignancy (c-statistic, 0.715; NPV, 0.90) in indeterminate thyroid specimens. The combination of CA4 and CRYAB for discriminating FTC from FA resulted in a better c-statistic of 0.75, sensitivity of 0.76, specificity of 0.59, positive predictive value (PPV) of 0.32, and NPV of 0.91. When comparing widely angioinvasive FTC from FA, the resultant c-statistic improved to 0.84, sensitivity of 0.75, specificity of 0.76, PPV of 0.11, and NPV of 0.99. Conclusions Loss of CA4 and increase in CRYAB immunoreactivity distinguish FTC from FA in indeterminate thyroid nodules on a thyroid TMA with an NPV of 91%. Further studies in preoperative patient fine needle aspiration (FNAs) are needed to validate these results. [ABSTRACT FROM AUTHOR]

An expedient protocol for the synthesis of 5-aryl-2,3-dihydropyrroles, starting from N-tosyl-protected 2-methylprop-2-en- 1-amine, alkynyl bromides, and arylboronic acids, is described. The sequential reaction sequence involves nucleophilic addition of the sulfonamide to the alkynyl bromide, followed by a palladium-catalyzed tandem intramolecular Heck and intermolecular Suzuki crosscoupling reaction of the bromoalkene adduct. [ABSTRACT FROM AUTHOR]

Background Schistosomiasis is a chronic infection, where the host immune response to the parasite changes from a predominantly Th1 to Th2 phenotype, when parasite enters the egg stage, restraining the host inflammatory immune responses to achieve a longer survival in the host. On the other hand, the development of Th2 responses causes immunopathological changes such as liver fibrosis. Therefore identification of schistosome-derived Th2 inducing molecules is important in the understanding of pathogenesis of schistosomiasis. A cyclophilin A homologue of Schistosoma japonicum was reported to be an egg-stage specific antigen, but its immunogenicity and immunoregulatory activities remain unknown. Methods We cloned and expressed the gene of cyclophilin A from Schistosoma japonicum (AY814078), named as SjCyP18 based on its molecular weight. The expression profiles in different stages of S. japonicum were examined by RT-PCR and immunofluorescence assay. The immunogenicity of SjCyP18 was measured by the presence of IgG in the sera from S. japonicum infected patients and animals, and the Th2-promting activities were examined by the subclass of immunoglobulins against SjCyP18 and by the IL-4 induction in T cells following footpad injection of SjCyP18. Results The cloned SjCyP18 has 65% homology with human or mouse cyclophilin A at the amino acid level. In contrast to reports as an egg-stage specific antigen, the gene was found to be expressed in all stages of S. japonicum. IgG responses against SjCyP18 were found in some S. japonicum infected patients and were significantly induced when infection become patent and produce eggs in infected mice. Furthermore, the Th2-promoting subclass of IgG1 was the predominant isotype in S. japonicum infected mice. More importantly, footpad injection of SjCyP18 induced a greater production of IL-4 than that of IFN-γ by lymphocytes compared to responses from PBS injection controls. Conclusion The cyclophilin A homologue found in S. japonicum is immunogenic and promotes Th2 responses in vivo which may contribute to the establishment of chronic infection by schistosomes. [ABSTRACT FROM AUTHOR]

Background: The study on the rare earth (RE)-doped layered double hydroxides (LDHs) has received considerable attention due to their potential applications in catalysts. However, the use of RE-doped LDHs as polymer halogen-free flame retardants was seldom investigated. Furthermore, the effect of rare earth elements on the hydrophobicity of LDHs materials and the compatibility of LDHs/polymer composite has seldom been reported. Methodology/Principal Findings: The stearate sodium surface modified Ni-containing LDHs and RE-doped Ni-containing LDHs were rapidly synthesized by a coprecipitation method coupled with the microwave hydrothermal treatment. The influences of trace amounts of rare earth ions La, Ce and Nd on the amount of water molecules, the crystallinity, the morphology, the hydrophobicity of modified Ni-containing LDHs and the adsorption of modifier in the surface of LDHs were investigated by TGA, XRD, TEM, contact angle and IR, respectively. Moreover, the effects of the rare earth ions on the interfacial compatibility, the flame retardancy and the mechanical properties of ethylene vinyl acetate copolymer (EVA)/ LDHs composites were also explored in detail.Conclusions/Significance: S-Ni0.1MgAl-La displayed more uniform dispersion and better interfacial compatibility in EVA matrix compared with other LDHs. Furthermore, the S-Ni0.1MgAl-La/EVA composite showed the best fire retardancy and mechanical properties in all composites. [ABSTRACT FROM AUTHOR]

Purpose. To compare the acute toxicities of IMRT to 3D-conformal radiation therapy (3DCRT) in the treatment of rectal cancer. Methods and Materials. Eighty-six patients with rectal cancer preoperatively treated with IMRT (n = 30) and 3DCRT (n = 56) were retrospectively reviewed. Rates of acute toxicity between IMRT and 3DCRT were compared for anorexia, dehydration, diarrhea, nausea, vomiting, weight loss, radiation dermatitis, fatigue, pain, urinary frequency, and blood counts. Fisher's exact test and chi-square analysis were applied to detect statistical differences in incidences of toxicity between these two groups of patients. Results. There were fewer hospitalizations and emergency department visits in the group treated with IMRT compared with 3DCRT (P = 0.005) and no treatment breaks with IMRT compared to 20% with 3DCRT (P = 0.0002). Patients treated with IMRT had a significant reduction in grade ⩾3 toxicities versus grade ⩽2 toxicities (P = 0.016) when compared to 3DCRT. The incidence of grade ⩾3 diarrhea was 9% among 3DCRT patients compared to 3% among IMRT patients (P = 0.31). Conclusions. IMRT for rectal cancer can reduce treatment breaks, emergency department visits, hospitalizations, and all grade ⩾3 toxicities compared to 3DCRT. Further evaluation and followup is warranted to determine late toxicities and long-term results of IMRT. [ABSTRACT FROM AUTHOR]

A straightforward, efficient, and more sustainable copper-catalyzed method has been developed for intramolecular N-arylation providing the benzimidazole ring system. With Cu2O (5 mol %) as the catalyst, DMEDA (10 mol %) as the ligand, and K2CO3 as the base, this protocol was applied to synthesize a small library of benzimidazoles in high yields. Remarkably, the reaction was exclusively carried out in water, rendering the methodology highly valuable from both environmental and economical points of view. [ABSTRACT FROM AUTHOR]

Background: A long-term existing schistosome infection can aid in maintaining immuno-homeostasis, thus providing protection against various types of autoimmune diseases to the infected host. Such benefits have often been associated with acute or egg stage infection and with the egg-induced Th2 response. However, since schistosome infection undergoes different stages, each associated with a specific induction of Th responses, the requirements for the ability of the different stages of schistosome infection to protect against autoimmune disease has not been elucidated. The present study was designed to study whether different stages of schistosome infection offer unique protection in collagen-induced arthritis and its mechanisms. Results: Arthritis susceptible strain DBA/1 male mice were infected with Schistosoma japonicum for either 2 weeks resulting in early stage infection or for 7 weeks resulting in acute or egg stage infection. Following Schistosoma japonicum infection, collagen II was administered to induce collagen-induced arthritis, an animal model for human rheumatoid arthritis. Infection by Schistosoma japonicum significantly reduced the severity and the incidence of experimental autoimmune collagen-induced arthritis. However, this beneficial effect can only be provided by a preestablished acute stage of infection but not by a pre-established early stage of the infection. The protection against collagen-induced arthritis correlated with reduced levels of anti-collagen II IgG, especially the subclass of IgG2a. Moreover, in protected mice increased levels of IL-4 were present at the time of collagen II injection together with sustained higher IL-4 levels during the course of arthritis development. In contrast, in unprotected mice minimal levels of IL-4 were present at the initial stage of collagen II challenge together with lack of IL-4 induction following Schistosoma japonicum infection. Conclusion: The protective effect against collagen-induced arthritis provided by Schistosoma japonicum infection is infection stage-dependent. Furthermore, the ability of schistosomiasis to negatively regulate the onset of collageninduced arthritis is associated with a dominant as well as long-lasting Th2 response at the initiation and development of autoimmune joint and systemic inflammation. [ABSTRACT FROM AUTHOR]

Histone/protein deacetylases (HDACs) regulate chromatin remodeling and gene expression as well as the functions of more than 50 transcription factors and nonhistone proteins. We found that administration of an HDAC inhibitor (HDACi) in vivo increased Foxp3 gene expression, as well as the production and suppressive function of regulatory T cells (Treg cells). Although Treg cells express multiple HDACs, HDAC9 proved particularly important in regulating Foxp3-dependent suppression. Optimal Treg function required acetylation of several lysines in the forkhead domain of Foxp3, and Foxp3 acetylation enhanced binding of Foxp3 to the Il2 promoter and suppressed endogenous IL-2 production. HDACi therapy in vivo enhanced Treg-mediated suppression of homeostatic proliferation, decreased inflammatory bowel disease through Treg-dependent effects, and, in conjunction with a short course of low-dose rapamycin, induced permanent, Treg-dependent cardiac and islet allograft survival and donor-specific allograft tolerance. Our data show that use of HDACi allows the beneficial pharmacologic enhancement of both the numbers and suppressive function of Foxp3+ Treg cells. [ABSTRACT FROM AUTHOR]