Methods for Investigating DNA Accessibility with Single Nucleosomes

Nucleosomes are the fundamental organizing unit of all eukaryotic genomes. Understanding how proteins gain access to DNA-binding sites located within nucleosomes is important for understanding DNA processing including transcription, replication, and repair. Single-molecule total internal reflection fluorescence (smTIRF) microscopy measurements can provide key insight into how proteins gain and maintain access to DNA sites within nucleosomes. Here, we describe methods for smTIRF experiments including the preparation of fluorophore-labeled nucleosomes, the smTIRF system, data acquisition, analysis, and controls. These methods are presented for investigating transcription factor binding within nucleosomes. However, they are applicable for investigating the binding of any site-specific DNA-binding protein within nucleosomes.

How does 3D endovaginal ultrasound compare to magnetic resonance imaging in the evaluation of levator ani anatomy?

INTRODUCTION AND HYPOTHESIS

To compare magnetic resonance imaging (MRI) to 3D endovaginal ultrasound (EVUS) in the evaluation of major levator ani defects in women with pelvic floor disorders.

METHODS

A total of 21 subjects with pelvic floor with complaints of pelvic floor disorders were included in this study. EVUS imaging of the levator ani muscle (LAM) was performed in all subjects, and the LA muscle groups of interest evaluated were the puboanalis (PA), puborectalis (PR), and pubovisceralis (PV) muscles. The right and left subdivisions were evaluated separately, and classified as (i) normal, normal with only minor irregularities, grossly abnormal, or absent, or (ii) by the levator ani deficiency (LAD) score and classified by no defect (complete attachment of muscle to the pubic bone), <50% detachment or loss, >50% detachment or loss, and completely detached or complete muscle loss. Paired data were analyzed with McNemar's test or Bowker's test of symmetry.

RESULTS

When unilateral LAM subdivisions were classified as "normal," "normal with minor irregularity," "grossly abnormal," and "absent," there were no significant differences between MRI and EVUS by categorization of LAM defects. Comparing "normal" versus "abnormal," there was no difference between imaging modalities. When compared by LAD score evaluation, there were no differences in the categorization of unilateral defects between MRI and EVUS.

CONCLUSIONS

Endovaginal 3D US is comparable to MRI in its ability to identify both normal and abnormal LAM anatomy. Neurourol. Urodynam. 36:409-413, 2017. © 2015 Wiley Periodicals, Inc.

Histone core phosphorylation regulates DNA accessibility

Nucleosome unwrapping dynamics provide transient access to the complexes involved in DNA transcription, repair, and replication, whereas regulation of nucleosome unwrapping modulates occupancy of these complexes. Histone H3 is phosphorylated at tyrosine 41 (H3Y41ph) and threonine 45 (H3T45ph). H3Y41ph is implicated in regulating transcription, whereas H3T45ph is involved in DNA replication and apoptosis. These modifications are located in the DNA-histone interface near where the DNA exits the nucleosome, and are thus poised to disrupt DNA-histone interactions. However, the impact of histone phosphorylation on nucleosome unwrapping and accessibility is unknown. We find that the phosphorylation mimics H3Y41E and H3T45E, and the chemically correct modification, H3Y41ph, significantly increase nucleosome unwrapping. This enhances DNA accessibility to protein binding by 3-fold. H3K56 acetylation (H3K56ac) is also located in the same DNA-histone interface and increases DNA unwrapping. H3K56ac is implicated in transcription regulation, suggesting that H3Y41ph and H3K56ac could function together. We find that the combination of H3Y41ph with H3K56ac increases DNA accessibility by over an order of magnitude. These results suggest that phosphorylation within the nucleosome DNA entry-exit region increases access to DNA binding complexes and that the combination of phosphorylation with acetylation has the potential to significantly influence DNA accessibility to transcription regulatory complexes.

Application of growing hierarchical SOM for visualisation of network forensics traffic data

Digital investigation methods are becoming more and more important due to the proliferation of digital crimes and crimes involving digital evidence. Network forensics is a research area that gathers evidence by collecting and analysing network traffic data logs. This analysis can be a difficult process, especially because of the high variability of these attacks and large amount of data. Therefore, software tools that can help with these digital investigations are in great demand. In this paper, a novel approach to analysing and visualising network traffic data based on growing hierarchical self-organising maps (GHSOM) is presented. The self-organising map (SOM) has been shown to be successful for the analysis of highly-dimensional input data in data mining applications as well as for data visualisation in a more intuitive and understandable manner. However, the SOM has some problems related to its static topology and its inability to represent hierarchical relationships in the input data. The GHSOM tries to overcome these limitations by generating a hierarchical architecture that is automatically determined according to the input data and reflects the inherent hierarchical relationships among them. Moreover, the proposed GHSOM has been modified to correctly treat the qualitative features that are present in the traffic data in addition to the quantitative features. Experimental results show that this approach can be very useful for a better understanding of network traffic data, making it easier to search for evidence of attacks or anomalous behaviour in a network environment.

A national audit of pollen immunotherapy for children in the United Kingdom: patient selection and programme safety

BACKGROUND

Specific immunotherapy (SIT) is an effective treatment for grass and/or tree pollen-induced severe allergic rhinoconjunctivitis. However, there are limited detailed data on the use of immunotherapy in children in the United Kingdom.

OBJECTIVES

We audited NHS paediatric practice against current national guidelines to evaluate patient selection, SIT modalities and adverse events (AEs).

METHODS

Paediatricians offering pollen SIT were identified through the British Society of Allergy and Clinical Immunology Paediatric Allergy Group (BSACI-PAG) and the database of SIT providers compiled for the Royal College of Physicians and Royal College of Pathologists 2010 joint working group. Standardized proformas were returned by 12 of 20 centres (60%), including 12 of 14 centres offering subcutaneous immunotherapy (SCIT) (85%).

RESULTS

Three hundred and twenty-three children, with mean age 11 years at initiation (69% boys), had undergone 528 SIT cycles (SCIT 31%) over 10 years. Fifty-five percent of all patients had asthma. Among SCIT programmes 24.5% patients had perennial (± seasonal) asthma; 75.6% of asthmatics undertaking SCIT had treatments at BTS/SIGN step 2 or above. AEs occurred frequently (50.4% of all SIT cycles) but were mild. In sublingual immunotherapy (SLIT) treatment, local intraoral immediate reactions were most common (44.9% SLIT cycles), as compared with delayed reactions around the injection site in SCIT (28.3% SCIT cycles). An asthma diagnosis had no impact on the number of cycles with AEs, or the severity reported. Few cycles (2.9%) were discontinued as a result of AE(s).

CONCLUSIONS AND CLINICAL RELEVANCE

Pollen SIT is available across England, though small numbers of children are being treated. Current national guidelines to exclude asthmatic children in SIT programmes are not being adhered to by most specialist paediatric allergy centres. SCIT and SLIT has been well tolerated. Review of patient selection criteria is needed and may allow greater use of this therapeutic option in appropriate clinical settings.

Fentanyl buccal soluble film (FBSF) for breakthrough pain in patients with cancer: a randomized, double-blind, placebo-controlled study

BACKGROUND

Fentanyl buccal soluble film (FBSF) has been developed as a treatment of breakthrough pain in opioid-tolerant patients with cancer. The objective of this study was to evaluate the efficacy of FBSF at doses of 200-1200 microg in the management of breakthrough pain in patients with cancer receiving ongoing opioid therapy.

PATIENTS AND METHODS

This was a multicenter, randomized, double-blind, placebo-controlled, multiple-crossover study that included opioid-tolerant adult patients with chronic cancer pain who experienced one to four daily episodes of breakthrough pain. The primary efficacy assessment was the sum of pain intensity differences at 30 min (SPID30) postdose.

RESULTS

The intent-to-treat population consisted of 80 patients with > or =1 post-baseline efficacy assessment. The least-squares mean (LSM +/- SEM) of the SPID30 was significantly greater for FBSF-treated episodes of breakthrough pain than for placebo-treated episodes (47.9 +/- 3.9 versus 38.1 +/- 4.3; P = 0.004). There was statistical separation from placebo starting at 15 min up through 60 min (last time point assessed). There were no unexpected adverse events (AEs) or clinically significant safety findings.

CONCLUSIONS

FBSF is an effective option for control of breakthrough pain in patients receiving ongoing opioid therapy. In this study, FBSF was well tolerated in the oral cavity, with no reports of treatment-related oral AEs.

Autoantibodies to a 140-kd protein in juvenile dermatomyositis are associated with calcinosis

OBJECTIVE

The identification of novel autoantibodies in juvenile dermatomyositis (DM) may have etiologic and clinical implications. The aim of this study was to describe autoantibodies to a 140-kd protein in children recruited to the Juvenile DM National Registry and Repository for UK and Ireland.

METHODS

Clinical data and sera were collected from children with juvenile myositis. Sera that recognized a 140-kd protein by immunoprecipitation were identified. The identity of the p140 autoantigen was investigated by immunoprecipitation/immunodepletion, using commercial monoclonal antibodies to NXP-2, reference anti-p140, and anti-p155/140, the other autoantibody recently described in juvenile DM. DNA samples from 100 Caucasian children with myositis were genotyped for HLA class II haplotype associations and compared with those from 864 randomly selected UK Caucasian control subjects.

RESULTS

Sera from 37 (23%) of 162 patients with juvenile myositis were positive for anti-p140 autoantibodies, which were detected exclusively in patients with juvenile DM and not in patients with juvenile DM-overlap syndrome or control subjects. No anti-p140 antibody-positive patients were positive for other recognized autoantibodies. Immunodepletion suggested that the identity of p140 was consistent with NXP-2 (the previously identified MJ autoantigen). In children with anti-p140 antibodies, the association with calcinosis was significant compared with the rest of the cohort (corrected P < 0.005, odds ratio 7.0, 95% confidence interval 3.0-16.1). The clinical features of patients with anti-p140 autoantibodies were different from those of children with anti-p155/140 autoantibodies. The presence of HLA-DRB1*08 was a possible risk factor for anti-p140 autoantibody positivity.

CONCLUSION

This study has established that anti-p140 autoantibodies represent a major autoantibody subset in juvenile DM. This specificity may identify a further immunogenetic and clinical phenotype within the juvenile myositis spectrum that includes an association with calcinosis.

The activation-induced cytidine deaminase (AID) efficiently targets DNA in nucleosomes but only during transcription

The activation-induced cytidine deaminase (AID) initiates somatic hypermutation, class-switch recombination, and gene conversion of immunoglobulin genes. In vitro, AID has been shown to target single-stranded DNA, relaxed double-stranded DNA, when transcribed, or supercoiled DNA. To simulate the in vivo situation more closely, we have introduced two copies of a nucleosome positioning sequence, MP2, into a supercoiled AID target plasmid to determine where around the positioned nucleosomes (in the vicinity of an ampicillin resistance gene) cytidine deaminations occur in the absence or presence of transcription. We found that without transcription nucleosomes prevented cytidine deamination by AID. However, with transcription AID readily accessed DNA in nucleosomes on both DNA strands. The experiments also showed that AID targeting any DNA molecule was the limiting step, and they support the conclusion that once targeted to DNA, AID acts processively in naked DNA and DNA organized within transcribed nucleosomes.

Dynamics of free surface perturbations along an annular viscous film

It is known that the free surface of an axisymmetric viscous film flowing down the outside of a thin vertical fiber under the influence of gravity becomes unstable to interfacial perturbations. We present an experimental study using fluids with different densities, surface tensions, and viscosities to investigate the growth and dynamics of these interfacial perturbations and to test the assumptions made by previous authors. We find that the initial perturbation growth is exponential, followed by a slower phase as the amplitude and wavelength saturate in size. Measurements of the perturbation growth for experiments conducted at low and moderate Reynolds numbers are compared to theoretical predictions developed from linear stability theory. Excellent agreement is found between predictions from a long-wave Stokes flow model [Craster and Matar, J. Fluid Mech. 553, 85 (2006)] and data, while fair to excellent agreement (depending on fiber size) is found between predictions from a moderate-Reynolds-number model [Sisoev, Chem. Eng. Sci. 61, 7279 (2006)] and data. Furthermore, we find that a known transition in the longer-time perturbation dynamics from unsteady to steady behavior at a critical flow rate Q(c) is correlated with a transition in the rate at which perturbations naturally form along the fiber. For Q<Q(c) (steady case), the rate of perturbation formation is constant. As a result, the position along the fiber where perturbations form is nearly fixed, and the spacing between consecutive perturbations remains constant as they travel 2 m down the fiber. For Q>Q(c) (unsteady case), the rate of perturbation formation is modulated. As a result, the position along the fiber where perturbations form oscillates irregularly, and the initial speed and spacing between perturbations varies, resulting in the coalescence of neighboring perturbations further down the fiber.

Anti-synthetase syndrome: a new autoantibody to phenylalanyl transfer RNA synthetase (anti-Zo) associated with polymyositis and interstitial pneumonia

OBJECTIVE

Autoantibodies directed against the aminoacyl tRNA synthetases are associated with myositis, arthritis, Raynaud's phenomenon, mechanic's hands, fever and interstitial pneumonia, clinically referred to as the anti-synthetase syndrome (ASS). The aim of this study was to characterize the autoantibody profile in a patient with clinical features of ASS whose routine diagnostic testing was negative for the previously identified anti-synthetase autoantibodies.

METHODS

Serum from a patient presenting with interstitial pneumonia followed by proximal myopathy, Raynaud's phenomenon and arthrlagia was analysed for autoantigen specificity by routine methods including indirect immunofluorescence, immunodiffusion, ELISA and immunoblotting. The autoantibody specificity was further analysed by RNA and protein immunoprecipitation. Novel autoantigens found on protein immunoprecipitation were further characterized using a proteomic approach, combining immunoprecipitation, SDS-PAGE and MALDI-TOF mass spectrometry.

RESULTS

Diagnostic testing on the patient's serum was negative by ELISA and immunodiffusion. Indirect immunofluorescence using Hep-2 cells was ANA negative, although a strong cytoplasmic speckle was seen. Immunoblotting with the patient serum displayed an unknown positive band at approximately 60 kDa. Protein immunoprecipitation revealed the presence of two proteins with molecular weights of approximately 60 and 70 kDa, and RNA immunoprecipitation revealed the presence of a band corresponding to a tRNA synthetase. Using a combination of immunoprecipitation and mass spectrometry, the novel immunoprecipitation targets were identified as phenylalanyl tRNA synthetase alpha and beta chains.

CONCLUSIONS

We report the identification of previously uncharacterized autoantibodies to phenylalanyl tRNA synthetase, entitled anti-Zo. This is the eighth anti-synthetase autoantibody in a patient with anti-synthetase syndrome.

Measurement and interpretation of pneumococcal IgG levels for clinical management

The detection of pneumococcal IgG antibodies is helpful for the evaluation of response to pneumococcal vaccination and need for revaccination. Results generated by the clinical assay which is currently used, in which the 23 valent polysaccharide vaccine is the antigen, were compared to those obtained by a capsular polysaccharide serotype-specific assay that measures IgG antibodies to 9 common serotypes causing invasive disease. Discrepancies in 21/47 (45%) of the results were observed in a direct comparison between the two assays. In each case a positive titre was obtained on the clinical assay but IgG levels on the serotype-specific assay were below the putative protective level of 0.2 micro g/ml for at least one of the 9 serotypes assayed. The generation of false positives by the current clinical assay is due to its lack of specificity. Antibodies to C-polysaccharide and all of the 23 serotypes included in the pneumococcal polysaccharide vaccine are incorporated into the final titre whereas the serotype-specific assay adsorbs out noncapsular polysaccharide antibodies. The discrepancies between the two assays highlight the importance of standardized assays that measure putative correlates of protection and demonstrate the need to re-evaluate the current clinical assay. A tool that allows the interpretation of the results of the serotype-specific assay is provided and its potential for assessing individual susceptibility levels to vaccine preventable pneumococcal infection is discussed.

The pre-operative identification of low-risk endometrialcancer: an audit of women treated in the South Island of New Zealand 1998-2000

OBJECTIVE

To determine whether pre-operative investigations identify a group of patients with low-risk endometrial cancer, who do not require tertiary referral for surgical staging or pelvic radiotherapy.

DESIGN

Retrospective chart review.

SETTING

South Island of New Zealand gynaecological oncology services.

SAMPLE

One hundred and forty consecutive patients with newly diagnosed endometrial cancer from 1988 to 2000.

METHODS

The results of preoperative investigations were compared with the final pathology.

MAIN OUTCOME MEASURES

Correlation of preoperative investigations with low risk disease. For the purpose of the study, women with grade 1 or 2 endometrioid tumours confined to the uterine body and less than 50% myometrial invasion were considered to have low risk disease.

RESULTS

In total, 50 women had low risk disease. Only 53% of patients with grade 1 tumours on initial biopsy had low risk disease. Women who had a grade 1 tumour at biopsy and, an ultrasound report with an endometrial thickness of less than 20 mm, and no evidence of myometrial invasion, cervical involvement or adnexal metastasis had a 76% chance of having low risk disease.

CONCLUSION

We were unable to accurately define the low risk group from pre-operative assessment.

Use of Leu3a/3b for the accurate determination of CD4 subsets for measurement of intracellular cytokines

BACKGROUND

Identification of human T-helper cell subsets is possible by measurement of intracellular cytokines after coincubation of lymphocytes with phorbol myristate acetate (PMA), calcium ionophore, and brefeldin A for up to 20 h. However, exposure to PMA leads to internalization of membrane CD4 and to loss of resolution of the CD4+ cells. Detection of CD3+CD8- cells or preselection of CD4+ cells prior to stimulation is more cumbersome than direct measurement of CD4+ cells. We report the use of the Leu3a/Leu3b multiclone for the accurate determination of CD4 cells after PMA stimulation.

METHODS

Peripheral blood lymphocytes were isolated from healthy normal donors and the proportion of CD3+ / CD4+ T cells was determined by flow cytometry before and after incubation with PMA, calcium ionophore, and brefeldin A for 20 h using a variety of anti-CD4 monoclonal antibodies.

RESULTS

The Leu3a/3b multiclone reagent was the only anti-CD4 monoclonal antibody capable of resolving more than 98% of the initial CD4+ events after incubation with PMA.

CONCLUSIONS

The higher signal-to-noise ratio associated with Leu3a3b reagent, compared with other CD4-specific antibodies available, allows the direct and accurate identification of the CD4 subset even after PMA treatment of cells.

Subfamilies of CR1 non-LTR retrotransposons have different 5'UTR sequences but are otherwise conserved

CR1 elements and CR1-related (CR1-like) elements are a novel family of non-LTR retrotransposons that are found in all vertebrates (reptilia, amphibia, fish, and mammals), whereas more distantly related elements are found in several invertebrate species. CR1 elements have several features that distinguish them from other non-LTR retrotransposons. Most notably, their 3' termini lack a polyadenylic acid (poly A) tail and instead contain 2-4 copies of a unique 8 bp repeat. CR1 elements are present at approximately 100,000 copies in the chicken genome. The vast majority of these elements are severely 5' truncated and mutated; however, six subfamilies (CR1-A through CR1-F) are resolved by sequence comparisons. One of these subfamilies (i.e. CR1-B) previously was analyzed in detail. In the present study, we identified several full-length elements from the CR1-F subfamily. Although regions within the open reading frames and 3' untranslated regions of CR1-F and CR1-B elements are well conserved, their respective 5' untranslated regions are unrelated. Thus, our results suggest that new CR1 subfamilies form when elements with intact open reading frames acquire new 5' UTRs, which could, in principle, function as promoters.

Detection of different strains of Potato virus Y and their mixed infections using competitive fluorescent RT-PCR

A competitive fluorescent RT-PCR assay (CF RT-PCR) was developed for the rapid and reliable detection and discrimination of the two most common strains of Potato virus Y (PVY) found in potato (necrotic and ordinary). The assay incorporates two strain specific primers labelled with fluorescent labels, used in conjunction with a universal PVY primer. The strain specific primers compete for the same annealing site which further increases specificity. Discrimination is conferred by the fluorescent labels; green PCR products for PVY(O) and red for PVY(N), whilst mixed infections are detected as orange PCR products without the need for staining agarose gels. The assay can be scaled up for the processing of 96 samples simultaneously, with the detection of PCR products directly using a fluorescent microtitre plate reader. The assay successfully discriminated between 20 isolates of PVY tested, and could be used for the direct detection of PVY in potato tubers.

Grit-blasted titanium femoral stem in cementless primary total hip arthroplasty: a 5- to 10-year multicenter study

A total of 133 cementless primary total hip arthroplasties using the Zweymuller-Alloclassic grit-blasted titanium tapered stem were performed in 3 institutions. The patient cohort was divided into 2 subgroups, nonselected and selected, on the basis of excellent bone stock and age (<65 years old at surgery). Acetabular components were all cementless, and bearing surfaces were all alumina-ceramic on polyethylene. After a 7.3-year average follow-up period (range, 5-10 years), 118 primary femoral replacements in 109 patients could be reviewed fully. Mean age at surgery was 55.7 years (range, 27-84 years). According to the Merle d'Aubigne and Charnley rating system, clinical results were graded excellent and good in 89% of hips and fair in 11%. Radiologically, early subsidence >2 mm could be detected in 4 hips (3.4%). Calcar atrophy and spot welds were noted in 77% and 82% of hips. Femoral osteolysis granuloma was noted in 4 hips (3.4%). There has been no stem fracture and no ceramic head breakage. The survivorship at 10 years with definite femoral aseptic loosening (radiographic failure) as the endpoint was 100% (95% Wilson confidence interval, 78.4%-100%; worst scenario, 95.4%). A significant difference between the nonselected and selected patient subgroups was observed only for early reoperation (P =.03) and proximal stress shielding (P =.01). Press-fitting but not filling the femoral canal with a rough titanium, straight, tapered femoral component represents, at intermediate follow-up, a promising cementless option in primary total hip arthroplasty.

Mechanisms of T cell peptide epitope-dependent late asthmatic reactions

Short peptide sequences corresponding to T cell epitopes have been identified in the major cat allergen Fel d 1. In order to directly activate allergen-specific T cells in cat-allergic asthmatic individuals, peptides were administered by intradermal injection. Subsequently, a proportion of subjects experienced a delayed reduction of airway calibre manifested as a decrease in FEV(1). Changes in lung function occurred approximately 3 h after peptide injection, peaked at 6 h and resembled an isolated late asthmatic reaction (LAR). Using molecular tissue typing techniques, it was determined that many of the individuals experiencing isolated LAR expressed particular HLA-DR molecules. These molecules were shown in subsequent experiments to bind individual peptides within the preparation and thus to activate T cells in a major histocompatibility complex (MHC)-restricted fashion. The precise mechanisms whereby MHC-restricted activation of allergen-specific T cells gives rise to bronchoconstriction are currently under investigation.

Interleukin-9 enhances interleukin-5 receptor expression, differentiation, and survival of human eosinophils

Interleukin-9 (IL-9) has been implicated in the pathogenesis of allergic disorders. To examine the interaction between IL-9 and eosinophils, we evaluated mature peripheral blood eosinophils for their expression of the specific alpha-subunit of the IL-9 receptor (IL-9R-alpha). The expression of IL-9R-alpha by human eosinophils was detected at the messenger RNA (mRNA) and protein levels by reverse transcriptase-polymerase chain reaction (RT-PCR), flow cytometry, and immunocytochemical analysis, respectively. Functional analyses demonstrated that recombinant human (rh)IL-9 inhibited in vitro peripheral blood human eosinophil apoptosis in a concentration-dependent manner. We then examined the role of IL-9 in eosinophil differentiation using the human cord blood CD34(+) cells and human promyelocytic leukemia cells (HL-60). The addition of IL-9 to CD34(+) cells cultured in IL-3 and IL-5 enhanced eosinophil development, and IL-9 alone induced the expression of IL-5R-alpha. IL-9 also up-regulated the IL-5R-alpha chain cell surface expression during terminal eosinophil differentiation of the HL-60 cell line. Our findings suggest that IL-9 may potentiate in vivo eosinophil function by increasing their survival and IL-5-mediated differentiation and maturation. Taken together, these results suggest a mechanism by which IL-9 potentiates airway and tissue eosinophilia.

Interleukin 5 regulates the isoform expression of its own receptor alpha-subunit

The receptor for interleukin 5 (IL-5) consists of a cytokine-specific alpha chain (IL-5Ralpha) and a signaling beta chain, which is shared with interleukin 3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF). These 3 cytokines can act in eosinophil development and activation in vitro, but gene deletion or antibody blocking of IL-5 largely ablates eosinophilic responses in models of allergic disease or helminth infection. We investigated factors acting in differential IL-5Ralpha gene splicing to generate either the membrane-anchored isoform (TM-IL-5Ralpha) which associates with the common beta chain to allow IL-5 responsiveness, or a secreted, antagonist variant (SOL-IL-5Ralpha). In a murine myeloid cell line (FDC-P1), transfected with minigenes allowing expression of either IL-5Ralpha variant, IL-5 itself, but not IL-3 or GM-CSF, stimulated a reversible switch toward expression of TM-IL-5Ralpha. A switch from predominantly soluble isoform to TM-IL-5Ralpha messenger RNA (mRNA) expression was also seen during IL-5-driven eosinophil development from human umbilical cord blood-derived CD34(+) cells; this was accompanied by surface expression of IL-5Ralpha and acquisition of functional responses to IL-5. IL-3 and GM-CSF also supported eosinophil development and up-regulation of TM-IL-5Ralpha mRNA in this system, but this was preceded by expression of IL-5 mRNA and was inhibited by monoclonal antibody to IL-5. These data suggest IL-5-specific signaling, not shared by IL-3 and GM-CSF, leading to a switch toward up-regulation of functional IL-5Ralpha and, furthermore, that IL-3 and GM-CSF-driven eosinophil development is dependent on IL-5, providing an explanation for the selective requirement of IL-5 for expansion of the eosinophil lineage. (Blood. 2000;95:1600-1607)

A quality assurance audit: phase III trial of maximal androgen deprivation in prostate cancer (TROG 96.01)

In 1997 the Trans-Tasman Radiation Oncology Group (TROG) performed a quality assurance (QA) audit of its phase III randomized clinical trial investigating the effectiveness of different durations of maximal androgen deprivation prior to and during definitive radiation therapy for locally advanced carcinoma of the prostate (TROG 96.01). The audit reviewed a total of 60 cases from 15 centres across Australia and New Zealand. In addition to verification of technical adherence to the protocol, the audit also incorporated a survey of centre planning techniques and a QA time/cost analysis. The present report builds on TROG's first technical audit conducted in 1996 for the phase III accelerated head and neck trial (TROG 91.01) and highlights the significant progress TROG has made in the interim period. The audit provides a strong validation of the results of the 96.01 trial, as well as valuable budgeting and treatment planning information for future trials. Overall improvements were detected in data quality and quantity, and in protocol compliance, with a reduction in the rate of unacceptable protocol violations from 10 to 4%. Audit design, staff education and increased data management resources were identified as the main contributing factors to these improvements. In addition, a budget estimate of $100 per patient has been proposed for conducting similar technical audits. The next major QA project to be undertaken by TROG during the period 1998-1999 is an intercentre dosimetry study. Trial funding and staff education have been targeted as the key major issues essential to the continued success and expansion of TROG's QA programme.

Selective removal of plutonium 238 from a canal sediment using a carbonate-chelant soil washing technology (ACT*DE*CON)

The Mound laboratory site in Miamisburg, OH, a former plutonium processing facility, contains approximately 40000 yd(3) (30,580 m3) of plutonium- and thorium-contaminated soils and sediments at levels that require remediation. Existing applicable remediation technologies are unsatisfactory, because they are expensive and do not provide volume reduction. ACT*DE*CON is a chemical soil leaching technology for the treatment of soils that utilizes contaminant dissolution via dilute selective solutions to remove radionuclides. In bench-scale tests, process parameters were developed for the optimal treatment of the Miami Erie Canal soil at the Mound site, combining the maximum plutonium removal with an acceptable amount of soil dissolution and minimizing the costs of reagents. Parameters evaluated included soil to extractant mass ratio, temperature, rinse solution composition, kinetics, and the application of several dewatering aids. Plutonium removal rates of >95% were achieved, and the residual plutonium in the treated soil proved to be very immobile-confirming that the process had removed the most accessible species of the radionuclide. Currently being tested at Mound is an engineering scale-up that includes an attrition scrubber, a counter-current extractor, and a reverse osmosis system. Economic evaluations based on bench-scale results put the treatment cost at US$278/yd(3) (US$364/m3), compared to US$350/yd(3) (US$458/m3) for the 'box-and-bury' baseline alternative treatment system.

The killing effect of photodynamic therapy using benzoporphyrin derivative on retinoblastoma cell line in vitro

OBJECTIVE

To evaluate the killing effect of photodynamic therapy (PDT) using new photosensitizer benzoporphyrin derivative complexed with human low density lipoprotein on retinoblastoma (RB) cell line in vitro.

METHODS

The experiment of photodynamic killing effect on RB cell line in vitro was performed by using benzoporphyrin derivative (BPD or Verteporfin) and monochromatic light at the wavelength around 690 nm. Seven BPD concentrations (2,500 ng/ml, 1,250 ng/ml, 625 ng/ml, 312.5 ng/ml, 156.25 ng/ml, 78.125 ng/ml, 39.0625 ng/ml) and three energy densities (1.2 J/cm2, 2.4 J/cm2 and 3.6 J/cm2) were applied. The damage of the tumor cells was evaluated by MTT assay 24 hours after PDT. The changes of the ultrastructure of RB cells were observed under eleceronic microscope 4 hours after PDT.

RESULTS

There was a significant dose-response relationship between tumor cell damage and BPD concentration in the medium under light irradiation at the energy density of 1.2 J/cm2. At each BPD concentration, the inhibition rate increased with the rise of energy density. RB tumor cell necrosis was found widely under electronic microscope.

CONCLUSIONS

This study suggested that RB cells are very sensitive to the PDT induced by BPD in vitro. RB tumor cell were directly killed by photodynamic effect induced by BPD.

Eosinophil development and bone marrow and tissue eosinophils in atopic asthma

BACKGROUND

Eosinophils develop from bone marrow (BM) progenitors, and interleukin-5 (IL-5) and eotaxin may act in expansion and mobilisation of BM eosinophils in asthma.

METHODS

We have examined phenotypic changes as CD34+ cells develop to the eosinophil lineage in vitro, and have evaluated BM eosinophils from asthmatic and control subjects for expression of the eotaxin receptor, CCR3.

RESULTS

Acquisition of receptors for IL-5 and CCR3 was an early event in eosinophil development. There were increased CD34+ cells, and mature and immature CCR3+ eosinophils in BM from asthmatics.

CONCLUSION

These data suggest that IL-5 may act early in eosinophil development, and that eotaxin has the capacity to mobilise a BM eosinophil pool in asthma.

CD34(+)/interleukin-5Ralpha messenger RNA+ cells in the bronchial mucosa in asthma: potential airway eosinophil progenitors

Eosinophil differentiation is thought to occur by the action of interleukin (IL)-5 on CD34(+) progenitor cells. The allergen-induced increase in eosinophil numbers in isolated airway preparations in vitro, and detection of increased numbers of circulating CD34(+) cells in atopic subjects, led us to the hypothesis that the eosinophil infiltration of the airway in asthma may result from local mucosal differentiation, in addition to recruitment from the bone marrow. We examined CD34(+) cell numbers by immunohistochemistry and IL-5 receptor alpha (IL-5Ralpha) messenger RNA (mRNA) expression by in situ hybridization in bronchial biopsies from atopic asthmatic patients, and from atopic and nonatopic control subjects. CD34(+) cell numbers were increased in the airway in atopic asthmatic and atopic nonasthmatic subjects. In contrast, CD34(+)/ IL-5Ralpha mRNA+ cells were increased in asthmatic subjects when compared with both atopic and nonatopic control subjects. Airway numbers of CD34(+)/IL-5Ralpha mRNA+ cells were correlated to airway caliber in asthmatic subjects and to eosinophil numbers. These findings support the concept that eosinophils may differentiate locally in the airway in asthma.

Increased mature and immature CCR3 messenger RNA+ eosinophils in bone marrow from patients with atopic asthma compared with atopic and nonatopic control subjects

BACKGROUND

Eosinophil infiltration of the bronchial mucosa is characteristic of asthma. Eosinophils differentiate from CD34(+) progenitors. Animal models suggest cooperation between IL-5 and eotaxin to allow rapid mobilization of a pool of bone marrow eosinophils followed by recruitment to the airway mucosa.

OBJECTIVE

The purpose of this study was to enumerate CD34(+) cell numbers in blood and bone marrow from atopic asthmatics and control subjects and to test the hypothesis that there is an increased bone marrow pool of CCR3(+) eosinophils in patients with atopic asthma, as compared with control subjects.

METHODS

Bone marrow aspirates and peripheral blood were obtained from volunteers with asthma and control volunteers. CD34(+) cell numbers were evaluated by flow cytometry, and eosinophil colony-forming activity was evaluated by methylcellulose cultures. Mature eosinophils, eosinophil myelocytes, metamyelocytes, and band forms (immature eosinophils) were enumerated by morphologic findings and immunocytochemistry for eosinophil cationic protein. CCR3 and eotaxin mRNA expression was examined by in situ hybridization, and protein expression was examined by immunocytochemistry. CCR3(+) cells were further identified with Chromotrope 2R staining.

RESULTS

CD34(+) cell numbers in bone marrow were increased in atopic subjects. Numbers of eosinophil colony-forming units in blood and bone marrow did not differ between groups. Percentages of both mature and immature eosinophils were increased in bone marrow from patients with atopic asthma, but not atopic patients with no asthma or normal control subjects. CCR3 was expressed by immature and mature bone marrow eosinophils. Eotaxin was expressed by bone marrow cells from all 3 groups, but there was no increase in subjects with asthma.

CONCLUSION

These findings suggest that in humans there is an increased bone marrow pool of CCR3(+) mature and immature eosinophils available for rapid mobilization in subjects with asthma but not in atopic subjects with no asthma.

Costimulation through CD86 is involved in airway antigen-presenting cell and T cell responses to allergen in atopic asthmatics

Atopic allergic asthma is characterized by activation of Th2-type T cells in the bronchial mucosa. Previous reports have suggested an important role for costimulation through the CD28/CTLA4-CD80/CD86 pathway in allergen activation of T cells in animal models of inhaled allergen challenge. However, human allergen-specific lines and clones were reported to be costimulation independent. We therefore examined CD80 and CD86 dependence of allergen-induced T cell proliferation and cytokine production in peripheral blood and bronchoalveolar lavage from atopic asthmatic subjects and controls. Both allergen-induced proliferation and IL-5 production from PBMC were inhibited by CTLA4-Ig fusion protein and anti-CD86, but not anti-CD80 mAbs. When allergen-specific CD4+ T cell lines from peripheral blood were examined, proliferation and cytokine production were found to be independent of CD80 or CD86 costimulation. However, when cells obtained directly from the airways were examined, allergen-induced proliferation of bronchoalveolar lavage T cells from atopic asthmatic subjects was inhibited by anti-CD86 but not anti-CD80. In addition, bronchoalveolar lavage-adherent cells from asthmatic, but not control subjects showed APC activity to autologous T cells. This was also inhibited by anti-CD86 but not anti-CD80. Thus allergen-induced T cell activation and IL-5 production in the airway in asthmatic subjects is susceptible to blockade by agents interfering with costimulation via CD86, and this may hold therapeutic potential in asthma.

Relation of cysteine conjugate nephrotoxicity to transport by the basolateral organic anion transport system in isolated S2 segments of rabbit proximal renal tubules

We examined basolateral transport of the radiolabeled zwitterionic nephrotoxic cysteine S-conjugate, S-(1,2-dichlorovinyl)-L-cysteine (DCVC), inhibition of such transport and the effects of inhibition of transport on the toxicity produced by DCVC in isolated S2 segments of rabbit proximal tubules. High concentrations of unlabeled DCVC itself and an unlabeled nontoxic cysteine S-conjugate, S-(2-benzothiazole)-L-cysteine cis-inhibited the basolateral uptake of radiolabeled DCVC by approximately 80 to 85%. High concentrations of para-aminohippurate, the prototype substrate for the basolateral organic anion transport system, and probenecid, a well-known inhibitor of basolateral organic anion transport, cis-inhibited the basolateral uptake of radiolabeled DCVC by approximately 70%, whereas a high concentration of L-phenylalanine had little effect. High concentrations of S-(2-benzothiazole)-L-cysteine and para-aminohippurate in the bathing medium with DCVC inhibited the loss of 86Rb (used as a K+ surrogate to measure toxicity) from S2 segments produced by DCVC alone to approximately the same extent as they inhibited uptake of DCVC. Under the same circumstances, probenecid completely inhibited 86Rb loss. These data indicate that in rabbit proximal renal S2 tubules basolateral entry of DCVC can occur to a major extent via the organic anion transport pathway and that inhibition of such entry can reduce toxicity to approximately the same extent that entry is reduced. They also suggest that probenecid provides additional protection from DCVC toxicity.

IL-3, IL-5, granulocyte-macrophage colony-stimulating factor receptor alpha-subunit, and common beta-subunit expression by peripheral leukocytes and blood dendritic cells

BACKGROUND

IL-3, IL-5, and granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors consist of cytokine-specific alpha-subunits, which associate with a shared signalling common beta-subunit (beta(c)) to form a high-affinity complex. The expression of IL-3, IL-5, and GM-CSF is upregulated in atopic inflammation, and these cytokines are thought to contribute to pathology through mechanisms that include eosinophil activation.

OBJECTIVE

We sought to examine the distribution of receptor expression between cells relevant to allergic inflammation from individual subjects and to compare atopic and nonatopic individuals.

METHODS

Peripheral blood was obtained from atopic and nonatopic volunteers. Cytokine-receptor expression was examined by flow cytometry with monoclonal antibodies specific for alpha-subunits and beta(c) in combination with phenotypic markers for eosinophils, basophils, neutrophils, dendritic cells, monocytes, and T cells.

RESULTS

Using a ligand-independent system, we confirmed the cellular distribution of IL-5Ralpha, IL-3Ralpha, and GM-CSFRalpha. IL-3Ralpha and GM-CSFRalpha were detected on high-affinity IgE receptor blood dendritic cells. Beta(c) expression was detected on basophils, eosinophils, neutrophils, and, at low levels, on monocytes and dendritic cells. There was intense staining of basophils for IL-3Ralpha relative to IL-5Ralpha, GM-CSFRalpha, and beta(c), whereas eosinophil-staining intensity was similar for IL-3Ralpha, IL-5Ralpha, GM-CSFRalpha, and beta(c). There were no significant differences between atopic and nonatopic subjects in cytokine-receptor staining.

CONCLUSION

IL-3Ralpha and GM-CSRalpha are shown on a newly defined population of Fc(epsilon)RI-high dendritic cells. The intense staining of basophils for IL-3Ralpha, relative to that of IL-5Ralpha and GM-CSFRalpha, is in contrast to eosinophils from the same subjects and may explain the higher sensitivity of basophils to IL-3 compared with IL-5 and GM-CSF. We found no evidence for downregulation of receptor expression in atopic compared with nonatopic subjects, suggesting that these receptors remain accessible as potential targets for therapeutic intervention in atopic allergic disease.

Na-dependent transport of S-(1,2-dichlorovinyl)-L-cysteine by renal brush-border membrane vesicles

Cytotoxicity after exposure to the nephrotoxicant S-(1, 2-dichloro-vinyl)-L-cysteine (DCVC) requires transport of this cysteine conjugate across the cell membrane. Although several basolateral transport pathways have been implicated in the uptake of this compound into renal proximal cells, the identity of the process or processes associated with transport across the luminal membrane is unclear. We used a preparation of luminal brush-border membrane vesicles to characterize the transport of [35S]DCVC in rabbit kidney. An inwardly directed Na-gradient stimulated the initial rate of DCVC uptake by 16-fold compared to uptake measured in the absence of Na+. The Na-dependent component of DCVC uptake was stimulated by imposition of an inside-negative electrical potential difference and was blocked by the presence of 5 mM unlabeled DCVC in the extravesicular solution. Transport of DCVC was adequately described by Michaelis-Menten kinetics with an apparent Kt of 0.5 mM. DCVC uptake was blocked by the presence in the extravesicular solution of 10 mM concentrations of phenylalanine, leucine and cysteine, but not by glycine, proline, lysine, taurine, N-acetyl DCVC, p-aminohippurate, lactate or succinate. Unlabeled DCVC inhibited uptake of [14C]phenylalanine by a mechanism that exerted a greater effect on the apparent Kt than on the Jmax of phenylalanine, implicating a possible competitive interaction between these compounds. The carrier-mediated permeability of DCVC (defined as the ratio of Jmax/Kt) in luminal brush border membranes was as large as or larger than that reported for a battery of other organic electrolytes, including several amino acids and organic anions. We conclude that luminal transport of DCVC in rabbit proximal cells is limited to a single Na-cotransport process that also handles phenylalanine.