Chemical Vapor Transport Synthesis of Fibrous Red Phosphorus Crystal as Anodes for Lithium-Ion Batteries

Red phosphorus (RP) is considered to be the most promising anode material for lithium-Ion batteries (LIBs) due to its high theoretical specific capacity and suitable voltage platform. However, its poor electrical conductivity (10^-12 S/m) and the large volume changes that accompany the cycling process severely limit its practical application. Herein, we have prepared fibrous red phosphorus (FP) that possesses better electrical conductivity (10^-4 S/m) and a special structure by chemical vapor transport (CVT) to improve electrochemical performance as an anode material for LIBs. Compounding it with graphite (C) by a simple ball milling method, the composite material (FP-C) shows a high reversible specific capacity of 1621 mAh/g, excellent high-rate performance and long cycle life with a capacity of 742.4 mAh/g after 700 cycles at a high current density of 2 A/g, and coulombic efficiencies reaching almost 100% for each cycle.

Significant differences in the electrochemical activity of black phosphorus anodes prepared under different atmospheres

The effects of atmosphere and temperature on the electrochemical reversibility of black phosphorus (BP) anodes were investigated. BP anodes prepared in ambient air exhibited much-enhanced electrochemical activity due to the newly formed Cu₃P phase. This work highlights the importance of maintaining intragranular electronic conduction for developing advanced BP-based anodes with high reversible capacities.

Non-inductive plasma vertical position measurement for the 1056 s discharge on EAST

Vertical position stability plays a crucial role in maintaining safe and reliable plasma operation for long-pulse fusion devices. In general, the vertical position is measured by using inductive magnetic coils installed inside the vacuum vessel; however, the integration drift effects are inherent for steady-state or long-pulse plasma operation. Developing a non-magnetic approach provides a fusion reactor-relevant steady-state solution that avoids the negative impact of integration drift. In this paper, we compare the non-inductively determined vertical position achieved by line-integrated interferometer and polarimeter measurements to that employing an inductive flux loop for a 1056 s discharge recently achieved on EAST (Experimental Advanced Superconducting Tokamak). Experimental results show that the non-inductive measurement is more robust than flux loops after 300 s if the integrator is not reset to suppress integrator drift. Real-time vertical position control using the non-inductive system is proposed for the next EAST experimental campaign.

Experimental Evidence of Intrinsic Current Generation by Turbulence in Stationary Tokamak Plasmas

High-β_{θe} (a ratio of the electron thermal pressure to the poloidal magnetic pressure) steady-state long-pulse plasmas with steep central electron temperature gradient are achieved in the Experimental Advanced Superconducting Tokamak. An intrinsic current is observed to be modulated by turbulence driven by the electron temperature gradient. This turbulent current is generated in the countercurrent direction and can reach a maximum ratio of 25% of the bootstrap current. Gyrokinetic simulations and experimental observations indicate that the turbulence is the electron temperature gradient mode (ETG). The dominant mechanism for the turbulent current generation is due to the divergence of ETG-driven residual flux of current. Good agreement has been found between experiments and theory for the critical value of the electron temperature gradient triggering ETG and for the level of the turbulent current. The maximum values of turbulent current and electron temperature gradient lead to the destabilization of an m/n=1/1 kink mode, which by counteraction reduces the turbulence level (m and n are the poloidal and toroidal mode number, respectively). These observations suggest that the self-regulation system including turbulence, turbulent current, and kink mode is a contributing mechanism for sustaining the steady-state long-pulse high-β_{θe} regime.

Reduced Graphene Oxide-Polypyrrole Aerogel-Based Coaxial Heterogeneous Microfiber Enables Ultrasensitive Pressure Monitoring of Living Organisms

Pressure sensors for living organisms can monitor both the movement behavior of the organism and pressure changes of the organ, and they have vast perspectives for the health management information platform and disease diagnostics/treatment through the micropressure changes of organs. Although pressure sensors have been widely integrated with e-skin or other wearable systems for health monitoring, they have not been approved for comprehensive surveillance and monitoring of living organisms due to their unsatisfied sensing performance. To solve the problem, here, we introduce a novel structural design strategy to manufacture reduced graphene oxide-polypyrrole aerogel-based microfibers with a typical coaxial heterogeneous structure, which significantly enhances the sensitivity, resolution, and stability of the derived pressure microsensors. The as-fabricated pressure microsensors exhibit ultrahigh sensitivities of 12.84, 18.27, and 4.46 kPa^-1 in the pressure ranges of 0-20, 20-40, and 40-65 Pa, respectively, high resolution (0.2 Pa), and good stability in 450 cycles. Furthermore, the microsensor is applied to detect the movement behavior and organic micropressure changes for mice and serves as a platform for monitoring micropressure for the integrative diagnosis both in vivo and in vitro of organisms.

[Effect of integrated schistosomiasis control measures in Hunan Province from 2004 to 2019]

OBJECTIVE

To examine the effect of the integrated schistosomiasis control measures in Hunan Province from 2004 to 2019, so as to provide insights into the development of the schistosomiasis elimination strategy.

METHODS

The integrated schistosomiasis control measures implemented by the health, agriculture, water resources, forestry, land and resources sectors were retrospectively collected in Hunan Province from 2004 to 2019, and the completion of each measure, cost of control measures, Schistosoma japonicum infections in humans and bovines, and snail status were analyzed each year. An index system for assessing the integrated schistosomiasis control effect was constructed using the Delphi method to calculate the integrated schistosomiasis control effect index. In addition, a cost-effect analysis was performed in terms of the decline in the prevalence of S. japonicum infections in humans and bovines, areas with snails in inner embankments, and areas with infected snails.

RESULTS

A total of 7 110 926 500 Yuan were invested into the integrated schistosomiasis control program of Hunan Province from 2004 to 2019. During the 16-year period, a total of 277 437.12 hm² snail habitats received molluscicidal treatments, 6 927 230 person-times given expanded chemotherapy, 2 116 247 bovine-times given expanded chemotherapy, 954 850 harmless toilets built, 290 359 bovines fenced, 136 666 bovines eliminated, 141 905 machines used to replace bovines, 39 048.63 hm² water lands improved as dry lands, 724.12 km irrigation regions improved, 3 994 300 populations covered with safe water, 191 102.89 hm² forests planted and 38 535.27 hm² lands leveled. The prevalence of S. japonicum infections was 4.29% in humans and 4.48% in bovines in Hunan Province in 2004, with 2 449.37 hm² snail habitats in inner embankments and 3 423.74 hm² infected snail areas. In 2019, the prevalence of S. japonicum infections reduced to 0 in both humans and bovines, and areas of snail habitats reduced to 540.92 hm² (77.92% reductions), while the areas with infected snails reduced to 0. The overall integrated schistosomiasis control effect index appeared a tendency towards a rise over years since 2004, and the integrated schistosomiasis control effect index was 97.35 in 2019; the annual mean costs for a 1% reduction in the prevalence of S. japonicum infections in 100 populations and 100 bovines were 70.11 Yuan and 4 204.78 Yuan, and the annual mean costs for a 1% reduction in the snail areas in inner embankments and infected snail areas were 2 010.20 Yuan and 1 298.09 Yuan, respectively.

CONCLUSIONS

The integrated control measures achieve remarkable effectiveness for schistosomiasis control in Hunan Province, with a remarkable decline in the prevalence of S. japonicum infections in humans and bovines and great shrinking of snail areas in inner embankments and infected snail areas. Adequate fund investment is required to improve the integrated schistosomiasis control measures and consolidate the control achievements.

Error correction associated with stray light for Faraday-effect polarimetry system on EAST

The polarimeter-interferometer system with 11 double-pass radial-view measurement chords has the ability to provide electron density and plasma current profiles, making it exceptionally useful in daily operation on the Experiment Advanced Superconducting Tokamak. However, due to limited optical access and intrinsic feedback, the stray lights arising from spurious reflections along the optical path (unwanted reflections from various optical components/mounts and transmissive optical elements such as windows, waveplates, and lenses as well as the detectors) distort the Faraday rotation measurements. Furthermore, the feedback light from the retro-reflector which is used to realize the double-pass configuration makes it even worse. A data processing approach to decrease the stray light influence is reported in this paper. Based on the theoretical model developed, the Faraday rotation angle is extracted by subtracting the deviation term which can be calculated with a simplified model. With this approach, the Faraday rotation oscillation during density ramp-up can be reduced from 2°-5° to 0.5°-1.5°, which reduces the Faraday rotation measurement errors significantly.

Bench test of phase measurement on dispersion interferometer for EAST

In recent years, different traditional interferometers have been the necessary diagnostic of electronic density measurement on fusion devices. Until now, two main problems always influence the density measurement: the mechanical vibration and fringe jump in the calculation. The dispersion interferometer (DI) with a long-wavelength infrared wavelength is a good choice because mechanical vibrations can be canceled and the fringe jump can be inhibited. This paper describes the bench test of phase measurement using a wedge instead of plasma on the DI. The results show good agreement with the theoretical calculations. In the background measurement, this DI without a vibration isolation system has good performance, and the drift of the baseline is less than 2 × 10¹⁷ m^-2 in 3 s and less than 5 × 10¹⁷ m^-2 in 400 s. Plasma data will be obtained during the next campaign on EAST (Experimental and Advanced Superconducting Tokamak).

High Electrochemical Performance Phosphorus-Oxide Modified Graphene Electrode for Redox Supercapacitors Prepared by One-Step Electrochemical Exfoliation

Phosphorus oxide modified graphene was prepared by one-step electrochemical anodic exfoliation method and utilized as electrode in a redox supercapacitor that contained potassium iodide in electrolytes. The whole preparation process was completed in a few minutes and the yield was about 37.2%. The prepared sample has better electrocatalysis activity for I⁻/I⁻₃ redox reaction than graphite due to the good charge transfer performance between phosphorus oxide and iodide ions. The maximum discharge specific capacitance is 1634.2 F/g when the current density is 3.5 mA/cm² and it can keep at 463 F/g after 500 charging–discharging cycles when the current density increased about three times.

High Performance of Supercapacitor from PEDOT:PSS Electrode and Redox Iodide Ion Electrolyte

Insufficient energy density and poor cyclic stability is still challenge for conductive polymer-based supercapacitor. Herein, high performance electrochemical system has been assembled by combining poly (3,4-ethylenedioxythiophene) (PEDOT):poly (styrene sulfonate) (PSS) redox electrode and potassium iodide redox electrolyte, which provide the maximum specific capacity of 51.3 mAh/g and the retention of specific capacity of 87.6% after 3000 cycles due to the synergic effect through a simultaneous redox reaction both in electrode and electrolyte, as well as the catalytic activity for reduction of triiodide of the PEDOT:PSS.

Effects of stray lights on Faraday rotation measurement for polarimeter-interferometer system on EAST

A double-pass radially view 11 chords polarimeter-interferometer system has been operated on the experimental advanced superconducting tokamak and provides important current profile information for plasma control. Stray light originating from spurious reflections along the optical path (unwanted reflections from various optical components/mounts and transmissive optical elements such as windows, waveplates, and lens as well as the detectors) and also direct feedback from the retro-reflector used to realize the double-pass configuration can both contribute to contamination of the Faraday rotation measurement accuracy. Modulation of the Faraday rotation signal due to the interference from multiple reflections is observable when the interferometer phase (plasma density) varies with time. Direct reflection from the detector itself can be suppressed by employing an optical isolator consisting of a λ/4-waveplate and polarizer positioned in front of the mixer. A Faraday angle oscillation during the density ramping up (or down) can be reduced from 5°-10° to 1°-2° by eliminating reflections from the detector. Residual modulation arising from misalignment and stray light from other sources must be minimized to achieve accurate measurements of Faraday rotation.

Ultra High Electrical Performance of Nano Nickel Oxide and Polyaniline Composite Materials

The cooperative effects between the PANI (polyaniline)/nano-NiO (nano nickel oxide) composite electrode material and redox electrolytes (potassium iodide, KI) for supercapacitor applications was firstly discussed in this article, providing a novel method to prepare nano-NiO by using β-cyelodextrin (β-CD) as the template agent. The experimental results revealed that the composite electrode processed a high specific capacitance (2122.75 F·g-1 at 0.1 A·g-1 in 0.05 M KI electrolyte solution), superior energy density (64.05 Wh·kg-1 at 0.2 A·g-1 in the two-electrode system) and excellent cycle performance (86% capacitance retention after 1000 cycles at 1.5 A·g-1). All those ultra-high electrical performances owe to the KI active material in the electrolyte and the PANI coated nano-NiO structure.

A shape memory polyurethane based ionic polymer–carbon nanotube composite

The blocking force of 25% GO–IPU is 5 times that of neat IPU.

Initial measurements of plasma current and electron density profiles using a polarimeter/interferometer (POINT) for long pulse operation in EAST (invited)

A double-pass, radially viewing, far-infrared laser-based POlarimeter-INTerferometer (POINT) system utilizing the three-wave technique has been implemented for diagnosing the plasma current and electron density profiles in the Experimental Advanced Superconducting Tokamak (EAST). POINT has been operated routinely during the most recent experimental campaign and provides continuous 11 chord line-integrated Faraday effect and density measurement throughout the entire plasma discharge for all heating schemes and all plasma conditions (including ITER relevant scenario development). Reliability of both the polarimetric and interferometric measurements is demonstrated in 25 s plasmas with H-mode and 102 s long-pulse discharges. Current density, safety factor (q), and electron density profiles are reconstructed using equilibrium fitting code (EFIT) with POINT constraints for the plasma core.

Optical configuration optimization and calibration for the POINT system on EAST

Calibration of the polarimeter system is one of the key elements to determine the overall measurement accuracy. The anisotropic reflection and transmission properties of the mesh beam splitters can easily distort the polarization state of the circularly polarized beams. Using a rotating crystal quartz λ/2-waveplate to replace the plasma can effectively allow us to obtain the ratio of the measured Faraday rotation angle to the known rotation angle of the waveplate. This ratio is used to estimate the calibration factor for each chord to be accurately determined and help to minimize distortions introduced by the wire-mesh beam splitters. With the novel configuration optimization, the distortion of polarization state is effectively eliminated.

Raf-kinase inhibitor protein attenuates microglia inflammation in an in vitro model of intracerebral hemorrhage

Microglia mediated neuroinflammation plays a crucial role in intracerebral hemorrhage (ICH). Raf kinase inhibitor protein (RKIP), a member of the phosphatidylethanolamine-binding protein (PEBP) family, is a negative regulator of inflammatory responses. However, the expression and anti-inflammatory effects of RKIP in microglia after ICH have not been reported. Therefore, in the current study, we investigated the effects of RKIP on inflammatory responses in erythrocyte lysate-treated BV2 microglia. Furthermore, we analyzed the detailed molecular mechanisms underlying the anti-inflammatory effects of RKIP in microglia. Our results showed that the expression level of RKIP was significantly decreased by erythrocyte lysate treatment in BV2 microglia. Overexpression of RKIP inhibited the production of pro-inflammatory molecules. In addition, overexpression of RKIP attenuated neuronal cell death induced by activated microglia. Moreover, RKIP suppressed the activation of NF-κB signaling pathway in erythrocyte lysis-treated BV2 cells. In conclusion, these data suggest that overexpression of RKIP attenuated microglia inflammation through inhibiting the NF-κB signaling pathway in erythrocyte lysis-treated BV2 cells. The present study provides evidence that RKIP may be used as an effective molecular target for the treatment of ICH.

A Bioinspired Swimming and Walking Hydrogel Driven by Light-Controlled Local Density

A hydrogel exhibits a real-time depth-controllable swimming motion via light-mediated modulation of local density to mimic the volume changes found in the bladders of fish. Moreover, other motions, e.g., rolling, somersaulting, and bipedal-like walking, can also be realized by designing or combining gel shapes, and the location of light.

Efficacy of early bundle therapy on moderate to severe aspiration pneumonia after cervical esophagogastrostomy for esophageal cancer

AIM

The aim of this paper was to investigate the methodology and clinical efficacy of early bundle therapy for complicated moderate to severe aspiration pneumonia after cervical esophagogastrostomy for esophageal cancer.

METHODS

A prospective study was conducted to analyze the clinical data from 49 patients who developed complicated moderate to severe aspiration pneumonia after cervical esophagogastrostomy for esophageal cancer. Among them, 27 patients underwent a bundle therapy-tracheostomy followed by ventilator-assisted breathing with reverse trendelenburg position, early goal-directed hemodynamic support, enteral nutrition by nasointestinal tube, effective antibiotic usage and large doses of expectorants in addition to the conventional treatments. The remaining 22 patients underwent conventional treatment (controls). The hospital fatality rates, incidence of serious complications, mechanical ventilation time and ICU length of stay of the two groups were compared.

RESULTS

Patients in the bundle therapy group had higher cure rate of pneumonia than the control group (P=0.041), significantly lower fatality rate than the controls (P=0.005), lower incidence of complications than the controls (P<0.05), shorter ICU length of stay than the control group (P=0.017), significantly shorter mechanical ventilation time (P=0.032), lower Acute Physiology and Chronic Health Evaluation II Score (P=0.036) and lower Clinical Pulmonary Infection Score (P=0.047).

CONCLUSION

Early bundle therapy can effectively improve the treatment efficacy for moderate to severe aspiration pneumonia after cervical esophagogastrostomy for esophageal cancer.

Preparation and Electrochemical Characterization of Mesoporous Polyaniline-Silica Nanocomposites as an Electrode Material for Pseudocapacitors

Mesoporous polyaniline-silica nanocomposites with a full interpenetrating structure for pseudocapacitors were synthesized via the vapor phase approach. The morphology and structure of the nanocomposites were deeply investigated by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis and nitrogen adsorption-desorption tests. The results present that the mesoporous nanocomposites possess a uniform particle morphology and full interpenetrating structure, leading to a continuous conductive polyaniline network with a large specific surface area. The electrochemical performances of the nanocomposites were tested in a mixed solution of sulfuric acid and potassium iodide. With the merits of a large specific surface area and suitable pore size distribution, the nanocomposite showed a large specific capacitance (1702.68 farad (F)/g) due to its higher utilization of the active material. This amazing value is almost three-times larger than that of bulk polyaniline when the same mass of active material was used.

Processing of lignin in urea–zinc chloride deep-eutectic solvent and its use as a filler in a phenol-formaldehyde resin

The main goal of our research deals with a new greener and more efficient lignin modification method to optimize its structural performance as a phenol-formaldehyde resin filler.

Synthesis and characterization of full interpenetrating structure mesoporous polycarbonate-silica spheres and p-phenylenediamine adsorption

As a common used and hardly emulsified amorphous thermoplastic, the bisphenol-A polycarbonates were used as the polymer candidate to form a novel monodispersed sub-micrometer mesoporous polymer-silica spheres with full interpenetrating structure. The synthesis procedure was based on a modified sol-gel approach in which the polycarbonate was plasticized in advanced by the surfactant of polymer emulsion. The mesoporous spheres possess a perfect uniform particle size and the polymer-silica spheres are held together by permanent entanglement in three dimensions. The defined crystallization of the polycarbonate was occurred when it was entrapped in the silica laminated matrix due to the plasticizing effect of the surfactant, and directly affected the thermal stability of the mesoporous spheres. The specific surface areas and pore diameters of mesoporous sphere were affected by the mass content and crystallization behavior of the polycarbonate. The p-phenylenediamine was used as adsorbate to investigate the cationic organics adsorption ability of the mesoporous spheres. The results shown that the polycarbonate-silica possess a well adsorption capacity for p-phenylenediamine by virtue of two kinds of hydrogen bond, and the maximum adsorption capacity was nearly 7.5 times larger than that of the hollow mesoporous silica.

Ligand-assisted fabrication of hollow CdSe nanospheres via Ostwald ripening and their microwave absorption properties

Hollow CdSe nanospheres were successfully synthesized by a ligand-assisted solvothermal method based on an Ostwald ripening mechanism. The hollow CdSe nanospheres were synthesized in benzyl alcohol under solvothermal conditions using Cd(Ac)2 and Se as the precursors, and tryptophan as a ligand. The resulting hollow structures consisted of small nanocrystallite building blocks. More importantly, the hollow CdSe nanospheres could be used as an excellent microwave absorber for cm- and mm-wave absorption, depending on the thickness of the absorber.

Association of the genetic polymorphisms of the ACE gene and the eNOS gene with lupus nephropathy in northern Chinese population

BACKGROUND

It has been reported that some single nucleotide polymorphisms (SNPs) of the angiotensin converting enzyme (ACE) gene and the endothelial nitric oxide synthase (eNOS) gene are associated with the development of systemic lupus erythematosus (SLE) and the progression of nephropathy. The aim of this study was to evaluate the possible association between six SNPs (A-5466C, T-3892C, A-240T, C1237T, G2215A and A2350G) of the ACE gene and two SNPs (T-786C and G894T) of the eNOS gene with lupus nephropathy in a northern Chinese population.

METHODS

In this study, 225 patients with lupus nephropathy were compared to 232 healthy controls, matched by gender, age and ethnicity. Following the extraction of genomic DNA from the leukocytes in the peripheral blood, the genotypes of the eight selected SNPs were determined by the method of PCR-RFLP; the haplotypes were inferred using PHASE 2.1. The associations between the SNPs and the risk of lupus nephropathy were analyzed using Chi-square test and Logistic regression with SPSS13.0 software.

RESULTS

Statistically significant differences of the allele frequency distribution of three SNPs (A-5466C, A2350G and G894T) were observed between cases and controls (P<0.05). Among the 53 haplotypes identified, the frequencies of five haplotypes (CTTCGA, ACTTAA, ACATGG, ACACGG and ATTCGA) were significantly different between cases and controls (P<0.05).

CONCLUSIONS

Our study indicated an association between the risk of lupus nephropathy and the sequence variations of both the ACE gene and the eNOS gene, which may play an important role in the pathogenesis of lupus nephropathy in the northern Chinese population. Further studies are warranted to validate our findings.

A non-canonical MEK/ERK signaling pathway regulates autophagy via regulating Beclin 1

Autophagy-essential proteins are the molecular basis of protective or destructive autophagy machinery. However, little is known about the signaling mechanisms governing these proteins and the opposing consequences of autophagy in mammals. Here we report that a non-canonical MEK/ERK module, which is positioned downstream of AMP-activated protein kinase (AMPK) and upstream of tuberous sclerosis complex (TSC), regulates autophagy by regulating Beclin 1. Depletion of ERK partially inhibited autophagy, whereas specific inhibition on MEK completely inhibited autophagy. MEK could bypass ERK to promote autophagy. Basal MEK/ERK activity conferred basal Beclin 1 by preventing disassembly of mammalian target of rapamycin complex 1 (mTORC1) and mTORC2. Activation of MEK/ERK by AMPK upon autophagy stimuli disassembled mTORC1 via binding to and activating TSC but disassembled mTORC2 independently of TSC. Inhibition of mTORC1 or mTORC2 by transiently or moderately activated MEK/ERK caused moderately enhanced Beclin 1 resulting in cytoprotective autophagy, whereas inhibition of both mTORC1 and mTORC2 by sustained MEK/ERK activation caused strongly pronounced Beclin 1 leading to cytodestructive autophagy. Our findings thus propose that the AMPK-MEK/ERK-TSC-mTOR pathway regulation of Beclin 1 represents different thresholds responsible for a protective or destructive autophagy.

Vitamin D3 induces autophagy of human myeloid leukemia cells

Vitamin D3 causes potent suppression of various cancer cells; however, significant supraphysiological concentrations of this compound are required for antineoplastic effects. Current combinatorial therapies with vitamin D3 are restricted to differentiation effects. It remains uncertain if autophagy is involved in vitamin D3 inhibition on leukemia cells. Here we show that besides triggering differentiation and inhibiting apoptosis, which was previously known, vitamin D3 triggers autophagic death in human myeloid leukemia cells. Inhibiting differentiation does not efficiently diminish vitamin D3 suppression on leukemia cells. Vitamin D3 up-regulates Beclin1, which binds to class III phosphatidylinositol 3-kinase to trigger autophagy. Vitamin D3 phosphorylates Bad in its BH3 domain, resulting in disassociation of the apoptotic Bad-Bcl-xL complex and association of Bcl-xL with Beclin1 and ultimate suppression of apoptotic signaling. Knockdown of Beclin1 eliminates vitamin D3-induced autophagy and inhibits differentiation but activates apoptosis, suggesting that Beclin1 is required for both autophagy and differentiation, and autophagy cooperates with differentiation but excludes apoptosis, in which Beclin1 acts as an interface for these three different cascades. Moreover, additional up-regulation of autophagy, but not apoptosis, dramatically improves vitamin D3 inhibition on leukemia cells. These findings extend our understanding of the action of vitamin D3 in antineoplastic effects and the role of Beclin1 in regulating multiple cellular cascades and suggest a potentially promising strategy with a significantly better antileukemia effect.

Interferon-gamma-modified dendritic cells suppress B cell function and ameliorate the development of experimental autoimmune myasthenia gravis

This study was designed to investigate the therapeutic effects of interferon (IFN)-gamma-modulated dendritic cells (DC) in experimental autoimmune myasthenia gravis (EAMG). We induced EAMG in Lewis rats by immunization with Torpedo nicotinic acetylcholine receptor (nAChR) and adjuvant. On day 33 post-immunization (p.i.), splenic DC were prepared, exposed to IFN-gamma alone (IFN-gamma-DC) or to IFN-gamma in combination with 1-methyl-DL-tryptophan (1-MT), the specific inhibitor of indoleamine 2,3-dioxygenase (IDO) (IFN-gamma + 1-MT-DC), and injected subcutaneously into rats with incipient EAMG on day 5 p.i. A control group of EAMG rats received naive DC on day 5 p.i., while another group received 1-MT every other day, intraperitoneally (p.i.), from days 5 to 41 p.i. The severity of clinical signs of EAMG was reduced dramatically in IFN-gamma-DC-treated rats compared to rats receiving naive DC, IFN-gamma + 1-MT-DC or 1-MT alone. The number of plasma cells secreting nAChR antibodies was reduced and the expression of B cell activation factor (BAFF) on splenic and lymph node mononuclear cells (MNC) was down-regulated in rats treated with IFN-gamma-DC. In vitro co-culture of MNC derived from EAMG rats with IFN-gamma-DC produced relatively few cells secreting nAChR antibodies. Addition of 1-MT to the co-culture significantly increased the number of cells secreting nAChR antibodies. We conclude that IFN-gamma-DC reduced the number of plasma cells secreting nAChR antibodies in an IDO-dependent manner and ameliorated the development of EAMG in Lewis rats.

CD8alpha dendritic cells and immune protection from experimental allergic encephalomyelitis

Dendritic cells (DC) represent a phenotypically heterogeneous population endowed with two important biological functions, immunity and tolerance. Here we report that the injection of splenic CD8alpha(+) DC, derived from rats with experimental allergic encephalomyelitis (EAE), delayed the onset and suppressed the severity of EAE in Lewis rats. This was accompanied by the lack of magnetic resonance imaging (MRI) lesions in the brain and spinal cord and by reduced numbers of inflammatory cells within the central nervous system. Injection of CD8(alpha+) DC inhibited T cell proliferation that may relate to increased interferon (IFN)-gamma and nitric oxide production. Although CD8(+)CD28(-) suppressor T cells, apoptotic cells and co-stimulatory molecules were not altered, CD4(+) T cells expressing interleukin (IL)-10 were augmented in rats receiving CD8alpha(+) DC compared to rats receiving total DC or medium. These results demonstrate that rat splenic CD8alpha(+) DC could provide a cellular basis for a novel, individualized immunotherapy using autologous DC as a complement to conventional therapy in diseases with an autoimmune background such as multiple sclerosis.

Disruption of the Cockayne syndrome B gene impairs spontaneous tumorigenesis in cancer-predisposed Ink4a/ARF knockout mice

Cells isolated from individuals with Cockayne syndrome (CS) have a defect in transcription-coupled DNA repair, which rapidly corrects certain DNA lesions located on the transcribed strand of active genes. Despite this DNA repair defect, individuals with CS group A (CSA) or group B (CSB) do not exhibit an increased spontaneous or UV-induced cancer rate. In order to investigate the effect of CSB deficiency on spontaneous carcinogenesis, we crossed CSB(-/-) mice with cancer-prone mice lacking the p16(Ink4a)/p19(ARF) tumor suppressor locus. CSB(-/-) mice are sensitive to UV-induced skin cancer but show no increased rate of spontaneous cancer. CSB(-/-) Ink4a/ARF(-/-) mice developed 60% fewer tumors than Ink4a/ARF(-/-) animals and demonstrated a longer tumor-free latency time (260 versus 150 days). Moreover, CSB(-/-) Ink4a/ARF(-/-) mouse embryo fibroblasts (MEFs) exhibited a lower colony formation rate after low-density seeding, a lower rate of H-Ras-induced transformation, slower proliferation, and a lower mRNA synthesis rate than Ink4a/ARF(-/-) MEFs. CSB(-/-) Ink4a/ARF(-/-) MEFs were also more sensitive to UV-induced p53 induction and UV-induced apoptosis than were Ink4a/ARF(-/-) MEFs. In order to investigate whether the apparent antineoplastic effect of CSB gene disruption was caused by sensitization to genotoxin-induced (p53-mediated) apoptosis or by p53-independent sequelae, we also generated p53(-/-) and CSB(-/-) p53(-/-) MEFs. The CSB(-/-) p53(-/-) MEFs demonstrated lower colony formation efficiency, a lower proliferation rate, a lower mRNA synthesis rate, and a higher rate of UV-induced cell death than p53(-/-) MEFs. Collectively, these results indicate that the antineoplastic effect of CSB gene disruption is at least partially p53 independent; it may result from impaired transcription or from apoptosis secondary to environmental or endogenous DNA damage.

A self-complementary, self-assembling microsphere system: application for intravenous delivery of the antiepileptic and neuroprotectant compound felbamate

Felbamate (FBM) is a novel antiepileptic drug (AED) and neuroprotectant (NP) compound that interacts with strychnine-insensitive (SI) glycine receptors in brain (IC(50) = 374 microM). FBM concentrations required to interact with SI glycine receptors are consistent with brain levels following oral and intraperitoneal administration of AED and NP doses. Because of the solubility limits of FBM, an intravenous (iv) form has not been developed. Nevertheless, an iv form could be important for the treatment of disorders such as status epilepticus and neuronal damage due to hypoxic/ischemic events. Substituted diketopiperazines precipitate in acid to form microspherical particles of uniform size ( approximately 2 microm). The microsphere system entraps drugs on precipitation and dissolves near physiological pH to release the drug cargo. Therefore, microspheres were used to produce an iv formulation of FBM. Mice were administered the FBM/microsphere (20-60 mg/kg FBM) and tested for protection against tonic extension seizures using maximal electroshock. The FBM/microsphere was effective in a time- and dose-dependent manner following iv administration. The median effective dose (ED(50)) for protection against MES seizures at 30 min was 27.2 mg/kg [95% confidence interval (CI) = 20.8-33.4, slope = 6.5]. The ED(50) for minimal motor impairment at 30 min was 167 mg/kg (95% CI = 155-177, slope = 28.1). Thus, the feasibility of encapsulating FBM or similar aqueous insoluble compounds in a microsphere system with delivery by the iv route for treatment of epilepsy and various central nervous system disorders has been clearly demonstrated. Studies were performed in accordance with the Guide for the Care and Use of Laboratory Animals.

[Malonaldehyde, superoxide dismutase and human cataract]

UV-spectrophotometry and fluorometry were used to study Malonaldehyde (MDA) and Superoxide Dismutase (SOD) in normal, cataractous human lenses and red blood cells of the patients with cataract. MDA content of senile and complicated cataractous lenses was significantly higher than that of normal human lenses, while that of complicated cataract was significantly higher than that of senile cataract. SOD activity of senile and complicated cataractous lenses was significantly lower than that of normal human lenses, while there was no marked difference between senile and complicated cataractous lenses. Significant correlation between cataractous lenses and red blood cells was not found in MDA content and SOD activity. There was a negative correlation between SOD and MDA in normal human lenses, but no correlation between SOD and MDA in cataractous lenses. The study shows that lipid peroxidation may be one of the possible mechanisms of cataractogenesis in human, and emphasizes the role of SOD in prevention of photoperoxidative damages to the tissues.