Unique roles of Schistosoma japonicum protein Sj16 to induce IFN-γ and IL-10 producing CD4(+)CD25(+) regulatory T cells in vitro and in vivo

Various proteins are expressed during different stages of schistosome development that are essential for cercarial penetration of vertebrate skin and evasion of host immune response. CD4(+)CD25(+) regulatory T cells are important in modulating immune responses towards helminth infections. Schistosoma japonicum protein Sj16 present in the secretions of schistosomula has been shown to have anti-inflammatory effects; however, it is uncertain whether Sj16 can induce CD4(+)CD25(+) regulatory T cells to participate in the regulation of early infection. In this study, we demonstrate a relationship between recombinant Sj16 (rSj16) and the induction of CD4(+)CD25(+) Foxp3(+) regulatory T cells. An increase in CD4(+)CD25(+) T cells was observed both in splenic cells from mice injected with rSj16 and the cells pretreated with rSj16, respectively. The induced CD4(+)CD25(+) T cells suppressed CD4(+)CD25(-) T-cell proliferation; furthermore, IFN-γ and IL-10 released from rSj16-stimulated cells contribute to this suppression. Additionally, rSj16-treated bone marrow dendritic cells (BMDCs) demonstrate an immature phenotype and play a role in the conversion of CD4(+)CD25(-) T cells into suppressive CD4(+)CD25(+) regulatory T cells. Our study identified a new CD4(+)CD25(+) T-cell population that induced by rSj16 and suggests that an IFN-γ-biased microenvironment during early infection of schistosome may favour the establishment of infection.

Biochemical and functional characterization of a recombinant monomeric factor VIII-Fc fusion protein

BACKGROUND

Hemophilia A results from a deficiency in factor VIII activity. Current treatment regimens require frequent dosing, owing to the short half-life of FVIII. A recombinant FVIII-Fc fusion protein (rFVIIIFc) was molecularly engineered to increase the half-life of FVIII, by 1.5-2-fold, in several preclinical animal models and humans.

OBJECTIVE

To perform a biochemical and functional in vitro characterization of rFVIIIFc, with existing FVIII products as comparators.

METHODS

 rFVIIIFc was examined by utilizing a series of structural and analytic assays, including mass spectrometry following lysyl endopeptidase or thrombin digestion. rFVIIIFc activity was determined in both one-stage clotting (activated partial thromboplastin time) and chromogenic activity assays, in the context of the FXase complex with purified components, and in both in vitro and ex vivo rotational thromboelastometry (ROTEM) assays performed in whole blood.

RESULTS

 rFVIIIFc contained the predicted primary structure and post-translational modifications, with an FVIII moiety that was similar to other recombinant FVIII products. The von Willebrand factor-binding and specific activity of rFVIIIFc were also found to be similar to those of other recombinant FVIII molecules. Both chromogenic and one-stage assays of rFVIIIFc gave similar results. Ex vivo ROTEM studies demonstrated that circulating rFVIIIFc activity was prolonged in mice with hemophilia A in comparison with B-domain-deleted or full-length FVIII. Clot parameters at early time points were similar to those for FVIII, whereas rFVIIIFc showed prolonged improvement of clot formation.

CONCLUSIONS

 rFVIIIFc maintains normal FVIII interactions with other proteins necessary for its activity, with prolonged in vivo activity, owing to fusion with the Fc region of IgG(1) .

How to assess positive end-expiratory pressure-induced alveolar recruitment?

Randomized trials fail to demonstrate a decrease in mortality when high Positive End-Expiratory Pressure (PEEP) is applied to patients with acute respiratory distress syndrome. Use of PEEP in all patients without taking into consideration specific lung morphology, potential for recruitment and risk of lung hyperinflation could be one of explanations. Assessment of alveolar recruitment in each individual patient appears to reach a good compromise between optimization of mechanical ventilation and reduction of lung injury due to systematic application of high PEEP. The purpose of the review was to discuss different methods to measure alveolar recruitment aimed at selecting optimal PEEP. The revision of the literature includes relevant human and animal studies published in the past ten years describing validated and promising methods. Computed tomography remains the reference method to assess regional PEEP-induced alveolar recruitment and hyperinflation. Lung ultrasound and pressure-volume (P-V) curve method are simple and repeatable at the bedside, but they can't provide information on lung hyperinflation. Electrical impedance tomography allows bedside assessment of tidal recruitment in dependent and nondependent regions. By measuring functional residual capacity, alveolar recruitment and strain can be estimated. Decremental PEEP titration preceded by recruitment maneuver has been suggested to define optimal PEEP that sustains oxygenation benefit of recruitment maneuver. Different methods are available to assess PEEP-induced alveolar recruitment. Lung ultrasound and P-V curve method can be easily used at bedside to assess lung recruitability and test optimal PEEP. Further development is required for bedside assessment combing alveolar recruitment with hyperinflation.

Chemical metabolism of medicinal compounds from natural botanicals

Traditional Chinese medicine (TCM) and its natural products are complex mixtures containing hundreds of chemically different constituents but only a few components are responsible for the pharmacological effects and bioactivities. In order to clarify the functional mechanism of active compounds, the studies on metabolism are of great significance and necessity. Previously, research mainly focused on the aspect of pharmacokinetics, however in recent years, chemical metabolism of active compounds has drawn increasing attention. Researches on the chemical metabolism of single phytochemicals help to understand the transformation process in vivo and mechanism of action, also contribute to pharmacodynamics and toxicology studies and new drug development. In the present paper, the chemical metabolism of nine categories of phytochemicals was reviewed. This review focused on pharmacological action, metabolic characteristics, metabolic pathways, metabolites and assay method of alkaloids, flavonoids, saponins, terpenoids, stilbenes, phenols, quinones, lignans and esters. The parent drugs, perhaps the metabolites, or they together play a role in pharmacological effects. And different routes of administration may lead to different results of transformation pathways and metabolites. Moreover, high-tech assay methods, particularly the combined use of modern instrument analytical techniques, are beneficial to the research of drug metabolism.

Pinellia pedatisecta agglutinin interacts with the methylosome and induces cancer cell death

Pinellia pedatisecta agglutinin (PPA) is a specific mannose-binding plant lectin accumulated in the tuber of P. pedatisecta. In the work presented, the cytotoxicity of PPA to cancer cells was investigated through exogenous expression. A PPA gene was transduced into normal and cancer cell lines through plasmid vectors, and the effect of PPA expression was examined. Results showed that PPA translocated into the nucleus, colocalized with DNA and induced cell death. A mannose-binding motif and a V¹⁰³-W¹³⁰ region directed the nuclear translocation of PPA. Coprecipitation, mass spectrometry and western blotting analysis further indentified that PPA was associated with the methylosome, which contains methylosome protein 50 and protein arginine methyltransferase 5 (PRMT5). Knockdown of PRMT5 significantly inhibited the PPA-induced cell death, suggesting that PPA used the methylosome as a target. Furthermore, Ad.surp-PPA, an adenovirus vector in which the PPA gene was controlled by a survivin promoter (surp), selectively inhibited the proliferation of cancer cell lines. Taken together, the expression of PPA gene elicited significant cytotoxicity to cancer cells through targeting the methylosome and might be developed into a novel agent in cancer gene therapy.

Canker on Bark of Populus spp. Caused by Cytospora tritici, a New Disease in China

Species of Cytospora Ehrenb. and associated teleomorphs cause dieback and canker on over 85 species of angiosperm and gymnosperm plants throughout the world (2). Cytospora tritici Punith. was first observed on Triticum asetivum in Germany in 1980 but may also affect many hardwoods (3). During a survey of landscape trees in 2007, Populus spp. with cankers were found in Fushun, Baoxing, and Luding counties and Chengdu city in Sichuan Province. In these trees, bark canker pathogens discolored the sapwood. During damp weather, conidia were pushed out and formed orange spore horns. Conidiomatal stromata were immersed in bark, prominent, and 1.53 ± 0.33 mm in diameter (n = 10). Discs were white to grey, circular, oval, and 0.59 ± 0.14 mm in diameter (n = 10), with one ostiole per disc. Ostioles were dark grey. Locules were multi-chambered, chambers irregular. Conidia were lelongate-allantoid shaped, hyaline, aseptate, 5.04 ± 0.65 μm long (n = 50), and 1.22 ± 0.13 μm wide (n = 50). Fragments (5 × 5 mm²) of the junction of diseased and healthy tissues were surface sterilized with 1% NaOCl for 30 s and then rinsed twice in sterile distilled water. The pieces were placed on potato dextrose agar (PDA) plates and incubated at 25°C for 7 days. The obtained isolates were cultured on PDA at 25°C in diffuse fluorescent light for 30 days. Upon isolation, the mycelium grew at a rate of 3 to 5 mm per day at 25°C, forming pale white-to-pure white flat colonies. Conidiomata never formed on PDA. ITS1-5.8S-ITS2 sequences were amplified via PCR from genomic DNA obtained from mycelia using universal primers ITS1 and ITS4 (4). The amplification products showed 100% sequence homology with C. tritici isolate DQ243812 from the GenBank database. The ITS sequences were submitted to GenBank (Accession No. JQ277333 to JQ277336). Pathogenicity was confirmed by inoculating 20 disinfected (70% ethanol) Populus tomentosa cuttings. Cuttings were incubated at 25°C for 30 days. Another two cuttings were treated with water agar as controls. In 18 of the 20 cuttings, the cambium developed a brown color and appeared water soaked 15 days later, whereas controls did not develop any symptoms. C. tritici was reisolated from symptomatic tissues. To our knowledge, this is the first report of C. tritici in China causing canker on Populus spp. Cytospora canker is common in practically all countries where poplar are grown. Canker expansion increases when tree defenses are compromised, usually by seasonal dormancy but also by drought, cold injury of wood, sun scald of bark, flooding of root, hail, freezing, or other stress (1). Future spread of C. tritici to western China is considered highly likely. References: (1) G. C. Adams et al. Stud. Mycol. 52:1, 2005. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ March 25, 2012. (3) E. Punithalingam. Nova Hedwigia 32:585, 1980. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

Novel quantum dots-carboxymethyl chitosan nanocomposite nitric oxide donors capable of detecting release of nitric oxide in situ

Nitric oxide (NO) donor compounds are primarily monofunctional in that they release NO under the requisite conditions. To detect the amount and duration of NO released, subsequent analysis methods are required. It would be advantageous if a NO donor compound could both release and detect NO at the same time. This would eliminate potential errors in the analysis. In this paper, novel cadmium telluride quantum dots (CdTe QD)-carboxymethyl chitosan (CMCS) nanocomposite NO donors, including both diazeniumdiolates and fluorescence probes, were fabricated by first synthesizing CdTe QD in CMCS aqueous solution and then reacting NO as well as ethyl bromide with the resultant CdTe QD-CMCS nanocomposites. Transmission electron microscopy, scanning electron microscopy and particle size analysis were used to examine the morphology and size distribution of the CdTe QD-CMCS nanocomposite NO donors. The donors are nanospheres with CdTe QD encapsulated and have dimensions of ~300 nm. Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and contact angle tests were employed to characterize the chemical structure of the donors, and the results also show that CdTe QD are well incorporated into CMCS, and many of them are close to the surface of the donors. The precursors of the donors exhibit a fluorescent effect, and the fluorescence can be quenched by NO. The donors can release NO spontaneously in a phosphate-buffered saline solution similar to a physiological environment, and can quantitatively detect the release of NO in situ based on fluorescence quenching of the donors by the NO.

CD40L demethylation in CD4(+) T cells from women with rheumatoid arthritis

We have previously demonstrated that DNA demethylation of CD40L on the X chromosome is responsible for female susceptibility to systemic lupus erythematosus (SLE). It is unknown whether aberrant methylation of the CD40L gene also contributes to the higher incidence of rheumatoid arthritis (RA) in females. In this study, we used real-time RT-PCR and flow cytometry to compare CD40L expression levels, and bisulfite sequencing to assess the methylation status of the CD40L promoter region. The results show that CD40L is upregrulated in CD4(+) T cells of female patients with RA. In addition, the CD40L promoter region in CD4(+) T cells from female RA patients was found to be demethylated, which corresponded with increased CD40L mRNA expression. These findings suggest that DNA demethylation contributes to CD40L expression in RA CD4(+) T cells and may in part explain the female preponderance of this disease.

Cigarette smoking extract causes hypermethylation and inactivation of WWOX gene in T-24 human bladder cancer cells

Genomic, epigenetic and expression alterations of WW domain containing oxidoreductase (WWOX) have been implicated in multiple tumor types. The current study was designed to examine the expression of WWOX in tumor tissues of human bladder transitional cell carcinoma (BTCC) and the influence of cigarette smoke extract (CSE) on WWOX expression and methylation status in T-24 bladder cancer cells. WWOX protein expression was evaluated by immunohistochemistry staining in a series of tumor samples from 78 patients with BTCC and 26 normal bladder tissues. The expression level and methylation status of WWOX in CSE-treated cells were examined by using quantitative Real-Time RT-PCR and methylation specific PCR, respectively. The expression levels of DNA methyltransferases (DNMTs) 1, 3A and 3B were also detected. We found that WWOX expression was absent or reduced in 79.5% (62/78) of BTCC tissues, but only in 19.2% (5/26) of normal bladder tissues. Loss of WWOX expression was correlated with tumor grade (P=0.019) and cigarette smoking (P=0.031), but was not associated with age, gender, tumor size and tumor number. Hypermethylation of WWOX promoter and exon 1 was specifically induced by CSE with a kinetics concurrent to the suppression of WWOX mRNA in T-24 cells. Furthermore, CSE treatment induced a significant time-dependent increase in the level of DNMT1, but has no effects on DNMT3A and DNMT3B. Taken together, these novel findings suggest that hypermethylation of WWOX induced by cigarette smoking may represent one underlying mechanism for the loss expression of WWOX in bladder cancer.

Demethylation of the FCER1G promoter leads to FcεRI overexpression on monocytes of patients with atopic dermatitis

BACKGROUND

Overexpression of the high-affinity receptor for immunoglobulin E on atopic monocytes and dendritic cells is known to contribute to the pathogenesis of atopic dermatitis (AD). However, it remains unclear what is the underlying mechanism of FcεRI deregulation. It has been speculated that epigenetic deregulation may play a role.

METHODS

Global DNA methylation levels of monocytes from 10 AD patients and 10 healthy controls were measured using a global DNA methylation kit. Bisulfite sequencing was performed to determine the methylation status of the FCER1G promoter region. FcεRIγ mRNA and FcεRI protein levels were detected by real-time RT-PCR, Western blotting, and flow cytometry, respectively. Patch methylation and the demethylating agent, 5-azacytidine, were used to determine the functional significance of methylation changes on FcεRI expression.

RESULTS

Monocytes from AD patients show a global hypomethylation, as well as a locus-specific hypomethylation at FCER1G promoter, as compared to healthy controls. Furthermore, this hypomethylation of FCER1G is inversely correlated with its expression. Patch methylation in combination with luciferase reporter assay confirmed the direct relationship between methylation and expression. Moreover, treating healthy monocytes with 5-azacytidine caused a reduction in methylation levels and an induction in FcεRIγ transcription and surface expression of FcεRI.

CONCLUSION

Demethylation of specific regulatory elements within the FCER1G locus contributes to FcεRI overexpression on monocytes from patients with AD.

Comparison of carotid atherosclerotic plaque characteristics by high-resolution black-blood MR imaging between patients with first-time and recurrent acute ischemic stroke

BACKGROUND AND PURPOSE

It has been shown that patients with a first ischemic stroke are at high risk of developing recurrent stroke due to carotid atherosclerotic plaque rupture. However, no one has defined the difference in plaques between initial and recurrent stroke. This study sought to investigate the characteristics of carotid plaque between patients with first-time and recurrent acute ischemic stroke by using MR imaging.

MATERIALS AND METHODS

Eighty-nine patients with recent acute ischemic stroke were recruited. All subjects underwent carotid high-resolution black-blood MR imaging. The index carotid arteries, defined as the arteries responsible for the ipsilateral stroke, were analyzed quantitatively and qualitatively. Carotid plaque burden and compositional features between patients with first-time and recurrent ischemic stroke were compared.

RESULTS

Of 89 recruited patients, 51 had first-time stroke and 38 had recurrent stroke. The mean WA, WT, and PWV were greater in patients with recurrent stroke than in patients with first-time stroke (all, P < .05). Compared with patients with first-time stroke, those with recurrent stroke showed significantly higher prevalence of calcification (44.7% versus 23.5%, P = .035) as well as a larger volume of LRNC (179.14 ± 254.81 mm(2) versus 71.65 ± 111.15 mm(2), P = .027). IPH or fibrous cap rupture or both were observed in 15.8% of patients with recurrent stroke and 3.9% of patients with first-time stroke.

CONCLUSIONS

Carotid plaques in patients with recurrent ischemic stroke are significantly aggravated compared with those in patients with first-time stroke, and monitoring carotid plaques in patients with initial stroke by MR imaging may be helpful for secondary stroke prevention.

Reverse line blot hybridisation screening of Pseudallescheria/Scedosporium species in patients with cystic fibrosis

The PCR-RLB (reverse line blot hybridisation) was applied as a molecular technique for the detection of members of Pseudallescheria and Scedosporium from sputum of patients with cystic fibrosis (CF). Fifty-nine sputum samples were collected from 52 CF patients, which were analysed by culture and PCR-RLB. Conventional and semi-selective culture yielded five positive samples, but the PCR-RLB hybridisation assay permitted the detection of members of Pseudallescheria/Scedosporium in 32 out of 52 patients (61.5%). In total, PCR-RLB yielded 47 positives. Pseudallescheria apiosperma was detected in 20 samples, while Pseudallescheria boydii and Pseudallescheria aurantiacum were detected in 17 and eight samples, respectively. Six samples gave a positive reaction with two distinct species-specific probes and one sample with three probes. In conclusion, the PCR-RLB assay described in this study allows the detection of Scedosporium spp. in CF sputum samples and the identification of Pseudallescheria apiosperma, P. boydii, S. aurantiacum, Scedosporium prolificans and Pseudallescheria minutispora.

Abnormal epigenetic modifications in peripheral blood mononuclear cells from patients with alopecia areata

BACKGROUND

Alopecia areata (AA) is a hair loss disease caused by T-cell-mediated autoimmune reactions against anagen-stage hair follicles. Although the exact aetiology is poorly understood, there is evidence to suggest that both genetic and environmental factors are involved in AA pathogenesis.

OBJECTIVES

To analyse DNA methylation and histone modification patterns in peripheral blood mononuclear cells (PBMCs) of patients with AA.

METHODS

PBMC samples were obtained from 25 patients with AA and 20 healthy controls. Global DNA methylcytosine levels, as well as histone acetylation and methylation levels, were measured by enzyme-linked immunosorbent assay. mRNA expression levels were determined using real-time quantitative reverse transcription-polymerase chain reaction.

RESULTS

Genomic DNA methylation in PBMCs of patients with AA was increased relative to controls. DNMT1, MBD1 and MBD4 expression levels were significantly higher in AA PBMCs than in controls, and DNMT1 transcription levels positively correlated with global DNA methylation levels in patient samples. Histone H3 acetylation was significantly increased and histone H3 lysine 4 methylation was significantly decreased in patient PBMCs compared with healthy controls. Histone H3 acetylation levels were positively correlated with AA disease severity, and with RANTES (CCL5) mRNA expression in PBMCs of patients with AA. These changes were accompanied by increased p300 (EP300), histone deacetylase 1 (HDAC1), myeloid/lymphoid or mixed lineage leukemia (MLL), SET7/9 (SETD7), G9A (EHMT2), JMJD2C (KDM4C) and JARID1A (KDM5A) expression, as well as reduced HDAC2, HDAC7, LSD1 (KDM1A), JMJD2A (KDM4A) and JMJD2B (KDM4B) expression.

CONCLUSIONS

DNA methylation and histone modification status are altered in PBMCs of patients with AA, possibly due to the deregulation of epigenetic regulatory genes. These changes may contribute to the activation of pathological immune responses in AA.

Mechanical responsiveness of the endothelial cell of Schlemm's canal: scope, variability and its potential role in controlling aqueous humour outflow

Primary open-angle glaucoma is associated with elevated intraocular pressure, which in turn is believed to result from impaired outflow of aqueous humour. Aqueous humour outflow passes mainly through the trabecular meshwork (TM) and then through pores formed in the endothelium of Schlemm's canal (SC), which experiences a basal-to-apical pressure gradient. This gradient dramatically deforms the SC endothelial cell and potentially contributes to the formation of those pores. However, mechanical properties of the SC cell are poorly defined. Using optical magnetic twisting cytometry and traction force microscopy, here we characterize the mechanical properties of primary cultures of the human SC cell, and for the first time, the scope of their changes in response to pharmacological agents that are known to modulate outflow resistance. Lysophosphatidic acid, sphingosine-1-phosphate (S1P) and thrombin caused an increase in cell stiffness by up to 200 per cent, whereas in most cell strains, exposure to latrunculin A, isoproterenol, dibutryl cyclic-AMP or Y-27632 caused a decrease in cell stiffness by up to 80 per cent, highlighting that SC cells possess a remarkably wide contractile scope. Drug responses were variable across donors. S1P, for example, caused 200 per cent stiffening in one donor strain but only 20 per cent stiffening in another. Isoproterenol caused dose-dependent softening in three donor strains but little or no response in two others, a finding mirrored by changes in traction forces and consistent with the level of expression of β(2)-adrenergic receptors. Despite donor variability, those drugs that typically increase outflow resistance systematically caused cell stiffness to increase, while in most cases, those drugs that typically decrease outflow resistance caused cell stiffness to decrease. These findings establish the endothelial cell of SC as a reactive but variable mechanical component of the aqueous humour outflow pathway. Although the mechanism and locus of increased outflow resistance remain unclear, these data suggest the SC endothelial cell to be a modulator of outflow resistance.

Magnetic resonance lymphography at 3T: a promising noninvasive approach to characterise inguinal lymphatic vessel leakage

PURPOSE

To explore the feasibility of using 3T high-resolution MR lymphangiography to characterize inguinal lymphatic vessel leakage (LVL).

MATERIALS AND METHODS

Sixteen patients with known inguinal LVL underwent 3T MR lymphangiography and T(2)-weighted imaging. The presence or absence of inguinal LVL and the responsible lymphatic vessels were determined using the above imaging modalities and confirmed by surgical procedure. Afterwards, fifteen patients with recurring LVL following conservative treatment were referred to surgical intervention.

RESULTS

Specific inguinal LVL enhancement patterns and leaking lymphatic vessels were detected in 15 of 16 patients. Compared to the SNR of enhanced lymph nodes, that of the enhanced LVL was significantly greater (t = 7.149, p < 0.01), thereby making it possible to differentiate between LVL sites and enhancing inguinal lymph nodes. Furthermore, the steepest contrast enhancement curve slope of enhanced LVL was lower than that of enhanced lymph nodes (t = -2.860, p = 0.02). After MR diagnosis, 15 patients successfully underwent open exploration and ligation of the leaking lymphatic vessel. Clinical follow-up did not demonstrate recurrence of lymphatic fluid in the groin.

CONCLUSIONS

High-resolution MR lymphangiography combined with T(2)-weighted imaging is a promising approach to identifying specific features of lymphatic vessel leakage in the groin.

Histone modifications and methyl-CpG-binding domain protein levels at the TNFSF7 (CD70) promoter in SLE CD4+ T cells

Abstract: In systemic lupus erythematosus (SLE), T lymphocytes overexpress CD70 ( TNFSF7 gene), leading to the synthesis of autoreactive IgGs. CD70 upregulation in SLE CD4+ T cells is associated with hypomethylation of TNFSF7 promoter. In this study, we explored histone modifications in the TNFSF7 promoter region in SLE CD4+ T cells, and characterized the effects of a DNA methyltransferase inhibitor (5-azaC) and a histone deacetylase inhibitor (TSA) on CD70 expression. We found that CD70 mRNA was significantly increased in active lupus CD4+ T cells, and in control cells treated with 5-azaC, TSA, or both. Histone H3 acetylation and dimethylated H3 lysine 4 (H3K4me2) levels were significantly elevated in patients with lupus, and both factors correlated positively with disease activity. MeCP2 protein levels within the TNFSF7 promoter decreased in patients with active lupus. Treatment of CD4+ T cells with 5-azaC alone significantly raised H3K4 dimethyl levels at the TNFSF7 locus. TSA treatment significantly increased H3 and H4 acetylation levels, as well as levels of H3K4 dimethylation at the TNFSF7 locus. Treatment with 5-azaC plus TSA enhanced H3 acetylation levels. These findings indicate that aberrant histone modifications within the TNFSF7 promoter may contribute to the development of lupus by increasing CD70 expression in CD4+ T cells.

Regulation of transcription of hypoxia-inducible factor-1α (HIF-1α) by heat shock factors HSF2 and HSF4

Hypoxia-inducible factor-1α (HIF-1α) is a principal regulator of angiogenesis and other cellular responses to hypoxic stress in both normal and tumor cells. To identify novel mechanisms that regulate expression of HIF-1α, we designed a genome-wide screen for expressed sequence tags (ESTs) that when transcribed in the antisense direction increase production of the HIF-1α target, vascular endothelial growth factor (VEGF), in human breast cancer cells. We discovered that heat shock factor (HSF) proteins 2 and 4-which previously have been implicated in the control of multiple genes that modulate cell growth and differentiation and protect against effects of environmental and cellular stresses-function together to maintain a steady state level of HIF-1α transcription and VEGF production in these cells. We show both HSFs bind to discontinuous heat shock element (HSE) sequences we identified in the HIF-1α promoter region and that downregulation of either HSF activates transcription of HIF-1α. We further demonstrate that HSF2 and HSF4 displace each other from HSF/HSE complexes in the HIF-1α promoter so that HIF-1α transcription is also activated by overexpression of either HSFs. These results argue that HSF2 and HSF4 regulate transcription of HIF-1α and that a critical balance between these HSF is required to maintain HIF-α expression in a repressed state. Our findings reveal a previously unsuspected role for HSFs in control of VEGF and other genes activated by canonical HIF-1α-mediated signaling.

Performance of an automated solid-phase red cell adherence system compared with that of a manual gel microcolumn assay for the identification of antibodies eluted from red blood cells

IgG antibodies coating red blood cells (RBCs) can be removed by elution procedures and their specificity determined by antibody identification studies. Although such testing is traditionally performed using the tube agglutination assay, prior studies have shown that the gel microcolumn (GMC) assay may also be used with comparable results. The purpose of this study was to compare an automated solid-phase red cell adherence (SPRCA) system with a GMC assay for the detection of antibodies eluted from RBCs. Acid eluates from 51 peripheral blood (PB) and 7 cord blood (CB) samples were evaluated by both an automated SPRCA instrument and a manual GMC assay. The concordance rate between the two systems for peripheral RBC samples was 88.2 percent (45 of 51), including cases with alloantibodies (n = 8), warm autoantibodies (n = 12), antibodies with no identifiable specificity (n = 2), and negative results (n = 23). There were six discordant cases, of which four had alloantibodies (including anti-Jka, -E, and -e) demonstrable by the SPRCA system only. In the remaining 2 cases, anti-Fya and antibodies with no identifiable specificity were demonstrable by the GMC assay only. All seven CB specimens produced concordant results, showing anti-A (n = 3), -B (n = 1), maternal anti-Jka (n = 2), or a negative result (n = 1). Automated SPRCA technology has a performance that is comparable with that of a manual GMC assay for identifying antibodies eluted from PB and CB RBCs.

Abnormal DNA methylation in peripheral blood mononuclear cells from patients with vitiligo

BACKGROUND

Vitiligo is a skin disorder characterized by the destruction of melanocytes by autoreactive lymphocytes. The genetic and environmental factors that trigger the autoimmune response are poorly understood. However, alterations to epigenetic DNA methylation patterns contribute to many other autoimmune diseases.

OBJECTIVES

To investigate genomic and gene-specific DNA methylation levels in peripheral blood mononuclear cells (PBMCs) of patients with vitiligo and to relate any changes to the expression of genes that regulate methylation, as well as the autoimmune-related gene IL10.

METHODS

We quantified global methylcytosine levels in PBMCs from 20 patients with vitiligo and 20 healthy controls. mRNA levels of DNA methyltransferases (DNMTs), methyl-DNA binding domain proteins (MBDs) and interleukin (IL)-10 were measured by real-time reverse transcriptase-polymerase chain reaction. Methylation of an IL10 regulatory element domain was determined by bisulphite genomic sequencing.

RESULTS

Genomic DNA methylation in PBMCs of patients with vitiligo was increased relative to healthy controls (P = 0·012). DNMT1, MBD1, MBD3, MBD4 and MeCP2 expression was significantly higher than in control PBMCs (P = 0·013, 0·001, 0·005, 0·001 and 0·001, respectively). MBD1 and MBD3 expression correlated positively with global DNA methylation in vitiligo PBMCs (MBD1: r = 0·519, P = 0·019; MBD3: r = 0·529, P = 0·016). IL10 expression was significantly decreased (P = 0·030), and an IL-10 enhancer region was hypermethylated in vitiligo PBMCs compared with controls (P = 0·014).

CONCLUSIONS

These data show that levels of DNA methylation are altered in PBMCs of patients with vitiligo, and this may contribute to disease activity by affecting the expression of autoimmunity-related genes.

Comparison of radionuclide lymphoscintigraphy and dynamic magnetic resonance lymphangiography for investigating extremity lymphoedema

Background

Lymphoscintigraphy is widely used to image the lymphatic system. The aim of this study was to compare lymphoscintigraphy and dynamic magnetic resonance lymphangiography (MRL) in the investigation of extremity lymphoedema.

Methods

Sixteen patients with primary extremity lymphoedema and two with Klippel–Trenaunay syndrome with lymphoedema were examined by lymphoscintigraphy using the tracer 99Tc-labelled dextran, and by MRL using gadobenate dimeglumine as contrast agent. Morphological abnormalities and functional state of the lymphatic systems of affected limbs were compared between the two imaging methods.

Results

Lymphatic vessels were imaged in 14 of 18 limbs with lymphoedema using MRL, compared with one of 18 using lymphoscintigraphy. MRL detected the inguinal nodes in 16 of 17 patients, whereas lymphoscintigraphy revealed inguinal nodes in only nine. MRL revealed more precise information about structural and functional abnormalities of lymph vessels and nodes than lymphoscintigraphy by real-time measurement of lymph flow in vessels and nodes.

Conclusion

Dynamic MRL was more sensitive and accurate than lymphoscintigraphy in the detection of anatomical and functional abnormalities in the lymphatic system in patients with extremity lymphoedema.

Depression, anxiety and quality of life in parents of children with epilepsy

OBJECTIVES

To assess the impact of childhood epilepsy on parental quality of life (QOL) and psychological health, and to investigate possible correlations between parental QOL and background variables as well as parental anxiety and depression.

SUBJECTS AND METHODS

Parents having an epileptic child (n = 263) and parents having a healthy child (n = 270) were enrolled. Groups were in balance for background variables. Short-Form Health Survey (SF-36) Questionnaire, Zung Depression Scale (ZDS) and Zung Anxiety Scale (ZAS) were applied to all parents. Patients were divided into the first visit group (newly diagnosed epilepsy) and follow-up visit group.

RESULTS

The parents of children with epilepsy had significantly lower QOL scores in SF-36 for all subscales and higher levels of depression and anxiety by using ZDS and ZAS. The factors correlated with parental QOL were seizure control, visit status, anxiety, depression, employment, cost of epilepsy, status epilepticus, drug side effect and age of parents.

CONCLUSIONS

Childhood epilepsy has a severe impact on parental QOL and psychological health, and recognition of possible correlations between parental QOL and background variables will be helpful to improve parental QOL.

Characterization of green fluorescent protein-expressing retinal cone bipolar cells in a 5-hydroxytryptamine receptor 2a transgenic mouse line

Retinal bipolar cells relay visual information from photoreceptors to third-order retinal neurons. Bipolar cells, comprising multiple types, play an essential role in segregating visual information into multiple parallel pathways in the retina. The identification of molecular markers that can label specific retinal bipolar cells could facilitate the investigation of bipolar cell functions in the retina. Transgenic mice with specific cell type(s) labeled with green fluorescent protein (GFP) have become a powerful tool for morphological and functional studies of neurons in the CNS, including the retina. In this study, we report a 5-hydroxytryptamine receptor 2a (5-HTR2a) transgenic mouse line in which expression of GFP was observed in two populations of bipolar cells in the retina. Based on the terminal stratification and immunostaining, all the strongly GFP-labeled bipolar cells were found to be type 4 cone bipolar cells. A small population of weakly labeled bipolar cells was also observed, which may represent type 8 or 9 cone bipolar cells. GFP expression in retinal cone bipolar cells was seen as early as postnatal day 5. In addition, despite severe retinal degeneration due to the presence of the rd1 mutation in this transgenic line, the density of GFP-labeled cone bipolar cells remained stable up to at least 6 months of age. This transgenic mouse line will be a useful tool for the study of type 4 cone bipolar cells in the retina under both normal and disease conditions.

Preoperative transcatheter arterial chemoembolization (TACE) and chemotherapy for hepatic colorectal metastases: Impact on hepatic histology and postoperative outcome

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Background: The objective was to evaluate the effect of preoperative administration of TACE and chemotherapy on hepatic injury and on postoperative outcome in patients with colorectal liver metastases (CRM) Methods: Seventy seven patients underwent hepatic resection for CRM between January 1999 and December 2007 were evaluated. Pathologic review of the non-tumorous liver was performed using established criteria for steatosis, steatohepatitis, and sinusoidal dilation. The effect of two different treatment and hepatotoxicity on postoperative outcome was analyzed. Results: 40 patients (51.9%) received no preoperative treatment, where 27 patients (35.0%) received preoperative chemotherapy, 10 patients (12.9%) performed TACE before resection. The median duration of TACE group was 4.5 months (range, 1–6 months), where the median duration of chemotherapy group was 5 cycles (range, 2–9 cycles). Chemotherapy regimen consisted of oxalipaltin plus FU (29.9%), or irinotecan plus FU (5.2%). On pathologic analysis, 36 patients (46.7%) had steatosis, 24 (31.1%) had sinusoidal dilation, and 8 (10.3%) had steatohepatitis. TACE was associated with steatosis, steatohepatosis and postoperative complication, when compared with no chemotherapy (all p<0.05).Among chemotherapy group,Oxaliplatin was associated with steatohepatitis compared with no preoperative treatment (13.0% v 0%, respectively; p<0.05). Irinotecan was associated with steatohepatitis compared with no preoperative treatment (50% v 0%, respectively; p=0.0006). Patients with preoperative chemotherapy had increased steatohepatitis compared with no treatment group (18.5% v 0%, respectively, p=0.0008), the postoperative morbility rate in preoperative chemotherapy (25.9%) was double that of the no-chemotherapy (12.5%), but this difference was not statistically significant (p=0.20). Preoperative chemotherapy was also not associated with 90-day mortality. Conclusions: Preoperative TACE treatment may cause pathological liver injury, and increase postoperative morbility after hepatic surgery. The standard preoperative chemotherapy regimen with Oxaliplatin or Irinotecan may increase steatohepatis.

No significant financial relationships to disclose.

Methylation of the OP-1 promoter: potential role in the age-related decline in OP-1 expression in cartilage

OBJECTIVE

An age-related decline in chondrocyte production of osteogenic protein-1 (OP-1) (Bone Morphogenetic Protein-7) may contribute to cartilage loss in osteoarthritis. This study was designed to determine if increased methylation of the OP-1 promoter might serve as a mechanism for the age-related decline in OP-1 expression.

METHODS

Human articular chondrocytes were isolated from cartilage obtained after death from tissue donors (ages 19-86 years) without a known history of arthritis. DNA was obtained from isolated chondrocytes in primary culture and analyzed for OP-1 promoter methylation by polymerase chain reaction (PCR) after bisulfite treatment. Cultured cells were treated with the DNA methyltransferase inhibitor 5-azacytidine and OP-1 production was measured in the media by enzyme-linked immunosorbent assay (ELISA). RNA was isolated to measure expression of insulin-like growth factor-1 (IGF-1), the IGF-1 receptor (IGF-1R), aggrecan, and OP-1 by real-time PCR.

RESULTS

Methylation of the OP-1 promoter was detected in chondrocytes isolated from tissue obtained from older adults and there was a positive correlation between age and OP-1 methylation status (n=22, R(2)=0.277, P=0.014). Inhibition of methylation in cultured cells with 5-azacytidine increased chondrocyte production of OP-1 protein and increased the expression of the IGF-1, the IGF-1R, aggrecan, and OP-1 genes but not GAPDH.

CONCLUSION

Age-related methylation of the OP-1 promoter may contribute to a decrease in OP-1 production in cartilage and a decrease in expression of OP-1 responsive genes such as IGF-1, the IGF-1R, and aggrecan.

N-acetylcysteine improves microcirculatory flow during smoking: new effects of an old drug with possible benefits for smokers

BACKGROUND

Cigarette smoking provokes marked acute changes in the microcirculatory vasculature, including a reduced blood flow velocity. In accordance with the hypothesis that the reduced blood flow is due to an imbalance between pro-oxidants and oxidants, we recently showed that most of the reduction could be reversed by a high dose of vitamin C.

HYPOTHESIS

In the present work we tested the hypothesis that N-acetylcysteine, a mucolyticum and an antioxidant, may have an effect on the smoking-induced changes observed by vital capillary microscopy of the nailfold.

METHODS

In all, 37 healthy volunteers of both genders and with varied smoking habits were treated with N-acetylcysteine 200 mg t.i.d. for 2 weeks. In vivo investigation of the microcirculation by capillaroscopy was performed before and after treatment.

RESULTS

Treatment with N-acetylcysteine significantly reduced the smoking-induced relative decrease in capillary blood flow velocity in a group of volunteers with varied smoking habits (p = 0.0016). The preventive effect was clearly significant in smokers (p = 0.003).

CONCLUSION

Treatment with N-acetylcysteine has a positive impact on microcirculatory flow during smoking, particularly in habitual smokers.