bluuebunny/crossref_metadata_2025 huggingface dataset:
CCR4 ligands are up-regulated in the airways of atopic asthmatics after segmental allergen challenge
Authors: Pilette C. , Francis J.N. , Till S.J. , Durham S.R.
Published: September 2008

T-helper (Th) 2 cytokines are thought to mediate most features of allergic inflammation in atopic asthma. However, it remains unclear whether chemokine pathways direct selective recruitment of Th2 cells to the airways during human allergic responses.

Bronchoalveolar lavage (BAL) was performed in 15 nonsmoking mild atopic asthmatics before and 24 h after a fibreoptic segmental allergen challenge, and chemokines related to T-cell recruitment were assayed by ELISA.

The Th2-related C-C chemokine (CCR)4 ligands, macrophage-derived chemokine/C-C chemokine ligand (CCL)22 and thymus and activation-regulated chemokine/CCL17, were increased in BAL after challenge. These chemokines correlated significantly with lymphocyte numbers and with interleukin (IL)‐5 and IL‐13 in post-challenge BAL. In contrast, two out of three putative Th1-related chemokines did not change. There were no alterations in monokine induced by interferon (IFN)‐γ/CXC chemokine ligand (CXCL)9 or macrophage inflammatory protein‐1α/CCL3; whereas a significant increase in IFN-induced protein-10kDa/CXCL10 was observed, which did not correlate with the T-cell influx. In peripheral mononuclear cells from atopic donors, CCL22 and CCL17 were induced by IL‐4 and IL‐13, further supporting the relationship between CCL22/CCL17 and Th2 cytokines. Finally, CCL22 was able to trigger actin polymerisation in peripheral CD4+ T-cells expressing CCR4.

Thus, C-C chemokine receptor 4 ligands are up-regulated in the airways of atopic asthmatics following allergen exposure, contribute to the T-cell influx to the airways and are closely related to the Th2-cytokine response.
Increased gastro-oesophageal reflux disease in patients with severe COPD
Authors: Casanova C. , Baudet J.S. , del Valle Velasco M. , Martin J.M. , Aguirre-Jaime A. , Pablo de Torres J. , Celli B.R.
Published: September 2008

The prevalence and clinical consequences of gastro-oesophageal reflux disease (GERD) in chronic obstructive pulmonary disease (COPD) are not well characterised.

The present study prospectively studied 42 males with COPD (forced expiratory volume in one second % predicted: 35%, range 20–49) and 16 healthy volunteers of similar age without respiratory or gastro-oesophageal symptoms. The diagnosis of GERD was confirmed using oesophageal 24 h pH monitoring. In the current study group, reflux symptoms were measured using the Vigneri score, cough and dyspnoea with the modified Medical Research Council questionnaire, and pulmonary function with bronchodilator response and health status using St George's Respiratory Questionnaire.

Pathological reflux was documented in 26 out of 42 patients (62%) and in three volunteers (19%). In patients with GERD, 15 patients (58%) did not report any reflux symptoms. There were no differences in symptoms, health status, bronchodilator treatment and pulmonary function test between patients with and without GERD. Oxygen desaturation coincided with episodes of increased oesophageal acidity in 40% of patients with GERD.

Patients with severe chronic obstructive pulmonary disease have a high prevalence of asymptomatic gastro-oesophageal reflux. The association between this reflux and oxygen desaturation deserves further attention.
High altitude impairs nasal transepithelial sodium transport in HAPE-prone subjects
Authors: Sartori C. , Duplain H. , Lepori M. , Egli M. , Maggiorini M. , Nicod P. , Scherrer U.
Published: September 2008

High-altitude pulmonary oedema (HAPE) occurs in predisposed individuals at altitudes >2,500 m. Defective alveolar fluid clearance secondary to a constitutive impairment of the respiratory transepithelial sodium transport contributes to its pathogenesis. Hypoxia impairs the transepithelial sodium transport in alveolar epithelial type II cellsin vitro. If this impairment is also presentin vivo, high-altitude exposure could aggravate the constitutive defect in sodium transport in HAPE-prone subjects, and thereby further facilitate pulmonary oedema.

Therefore, the aim of the current study was to measure the nasal potential difference (PD) in 21 HAPE-prone and 29 HAPE-resistant subjects at low altitude and 30 h after arrival at high altitude (4,559 m).

High-altitude exposure significantly decreased the mean±sd nasal PD in HAPE-prone (18.0±6.2versus12.5±6.8 mV) but not in HAPE-resistant subjects (25.6±9.4versus22.9±9.2 mV). This altitude-induced decrease was not associated with an altered amiloride-sensitive fraction, but was associated with a significantly lower amiloride-insensitive fraction of the nasal PD.

These findings provide evidencein vivothat an environmental factor may impair respiratory transepithelial sodium transport in humans. They are consistent with the concept that in high-altitude pulmonary oedema-susceptible subjects, the combination of a constitutive and an acquired defect in this transport mechanism facilitates the development of pulmonary oedema during high-altitude exposure.
Effects of tiotropium on lung hyperinflation, dyspnoea and exercise tolerance in COPD
Authors: O'Donnell D.E. , Flüge T. , Gerken F. , Hamilton A. , Webb K. , Aguilaniu B. , Make B. , Magnussen H.
Published: September 2008

The aim of this study was to test the hypothesis that use of tiotropium, a new long-acting anticholinergic bronchodilator, would be associated with sustained reduction in lung hyperinflation and, thereby, would improve exertional dyspnoea and exercise performance in patients with chronic obstructive pulmonary disease.

A randomised, double-blind, placebo-controlled, parallel-group study was conducted in 187 patients (forced expiratory volume in one second 44±13% pred): 96 patients received 18 µg tiotropium and 91 patients received placebo once daily for 42 days. Spirometry, plethysmographic lung volumes, cycle exercise endurance and exertional dyspnoea intensity at 75% of each patient's maximal work capacity were compared.

On day 42, the use of tiotropium was associated with the following effects at pre-dose and post-dose measurements as compared to placebo: vital capacity and inspiratory capacity (IC) increased, with inverse decreases in residual volume and functional residual capacity. Tiotropium increased post-dose exercise endurance time by 105±40 s (21%) as compared to placebo on day 42. At a standardised time near end-exercise (isotime), IC, tidal volume and minute ventilation all increased, whilst dyspnoea decreased by 0.9±0.3 Borg scale units.

In conclusion, the use of tiotropium was associated with sustained reductions of lung hyperinflation at rest and during exercise. Resultant increases in inspiratory capacity permitted greater expansion of tidal volume and contributed to improvements in both exertional dyspnoea and exercise endurance.
Endobronchial ultrasound to assess airway wall thickening: validationin vitroandin vivo
Authors: Shaw T.J. , Wakely S.L. , Peebles C.R. , Mehta R.L. , Turner J.M. , Wilson S.J. , Howarth P.H.
Published: September 2008

Endobronchial ultrasound (EBUS) allows identification of airway wall structures and could potentially be utilised forin vivostudies of airway thickening in asthma. The present study investigated whether inflation of the fluid-filled balloon sheath over the transducer (necessary to provide sonic coupling with the airway wall) influencedin vitromeasurements.In vivocomparability of EBUS with high resolution computed tomography scanning (HRCT), an established method for measuring wall thickness, was determined in control subjects.

The airway diameter and wall thickness were studied using EBUS in 24 cartilaginous airways obtained from four sheep, before and after balloon sheath inflation during immersion in saline. To assess EBUSversusHRCT comparability of airway measuresin vivo, 12 control subjects underwent imaging of the posterior basal bronchus of the right lower lobe by both techniques. Intra- and interobserver agreement were also assessed.

Results with and without the balloon sheath gave comparable measures of airway internal diameter and wall thicknessin vitro. Statistical analysis showed agreement between EBUS and HRCT, and intra- and interobserver variabilityin vivo.

The current study concludes that endobronchial ultrasound, which does not present a radiation risk, could be utilised in thein vivostudy of cartilaginous airway wall remodelling in respiratory diseases, such as asthma.
caBIG™ VISDA: Modeling, visualization, and discovery for cluster analysis of genomic data
Authors: Zhu Yitan , Li Huai , Miller David J , Wang Zuyi , Xuan Jianhua , Clarke Robert , Hoffman Eric P , Wang Yue
Published: September 2008

Background

The main limitations of most existing clustering methods used in genomic data analysis include heuristic or random algorithm initialization, the potential of finding poor local optima, the lack of cluster number detection, an inability to incorporate prior/expert knowledge, black-box and non-adaptive designs, in addition to the curse of dimensionality and the discernment of uninformative, uninteresting cluster structure associated with confounding variables.

Results

In an effort to partially address these limitations, we develop the VIsual Statistical Data Analyzer (VISDA) for cluster modeling, visualization, and discovery in genomic data. VISDA performs progressive, coarse-to-fine (divisive) hierarchical clustering and visualization, supported by hierarchical mixture modeling, supervised/unsupervised informative gene selection, supervised/unsupervised data visualization, and user/prior knowledge guidance, to discover hidden clusters within complex, high-dimensional genomic data. The hierarchical visualization and clustering scheme of VISDA uses multiple local visualization subspaces (one at each node of the hierarchy) and consequent subspace data modeling to reveal both global and local cluster structures in a "divide and conquer" scenario. Multiple projection methods, each sensitive to a distinct type of clustering tendency, are used for data visualization, which increases the likelihood that cluster structures of interest are revealed. Initialization of the full dimensional model is based on first learning models with user/prior knowledge guidance on data projected into the low-dimensional visualization spaces. Model order selection for the high dimensional data is accomplished by Bayesian theoretic criteria and user justification applied via the hierarchy of low-dimensional visualization subspaces. Based on its complementary building blocks and flexible functionality, VISDA is generally applicable for gene clustering, sample clustering, and phenotype clustering (wherein phenotype labels for samples are known), albeit with minor algorithm modifications customized to each of these tasks.

Conclusion

VISDA achieved robust and superior clustering accuracy, compared with several benchmark clustering schemes. The model order selection scheme in VISDA was shown to be effective for high dimensional genomic data clustering. On muscular dystrophy data and muscle regeneration data, VISDA identified biologically relevant co-expressed gene clusters. VISDA also captured the pathological relationships among different phenotypes revealed at the molecular level, through phenotype clustering on muscular dystrophy data and multi-category cancer data.
Improving peptide-MHC class I binding prediction for unbalanced datasets
Authors: Sales Ana Paula , Tomaras Georgia D , Kepler Thomas B
Published: September 2008

Background

Establishment of peptide binding to Major Histocompatibility Complex class I (MHCI) is a crucial step in the development of subunit vaccines and prediction of such binding could greatly reduce costs and accelerate the experimental process of identifying immunogenic peptides. Many methods have been applied to the prediction of peptide-MHCI binding, with some achieving outstanding performance. Because of the experimental methods used to measure binding or affinity between peptides and MHCI molecules, however, available datasets are enriched for nonbinders, and thus highly unbalanced. Although there is no consensus on the ideal class distribution for training sets, extremely unbalanced datasets can be detrimental to the performance of prediction algorithms.

Results

We have developed a decision-theoretic framework to construct cost-sensitive trees to predict peptide-MHCI binding and have used them to 1) Assess the impact of the training data's class distribution on classifier accuracy, and 2) Compare resampling and cost-sensitive methods as approaches to compensate for training data imbalance. Our results confirm that highly unbalanced training sets can reduce the accuracy of classifier predictions and show that, in the peptide-MHCI binding context, resampling methods do not improve the classifier performance. In contrast, cost-sensitive methods significantly improve accuracy of decision trees. Finally, we propose the use of a training scheme that, when the training set is enriched for nonbinders, consistently improves the overall classifier accuracy compared to cost-insensitive classifiers and, in particular, increases the sensitivity of the classifiers. This method minimizes the expected classification cost for large datasets.

Conclusion

Our method consistently improves the performance of decision trees in predicting peptide-MHC class I binding by using cost-balancing techniques to compensate for the imbalance in the training dataset.
An in vivo reporter of BMP signaling in organogenesis reveals targets in the developing kidney
Authors: Blank Ulrika , Seto Marianne L , Adams Derek C , Wojchowski Don M , Karolak Michele J , Oxburgh Leif
Published: September 2008

Background

Bone morphogenetic proteins (BMPs) regulate essential processes during organogenesis, and a functional understanding of these secreted proteins depends on identification of their target cells. In this study, we generate a transgenic reporter for organogenesis studies that we use to define BMP pathway activation in the developing kidney.

Results

Mouse strains reporting on BMP pathway activation were generated by transgenically expressing β-galactosidase under the control of BMP responsive elements from Id1. Reporter expression corresponds well with immunoassays for pathway activation in all organs studied, validating the model. Using these reporters we have generated a detailed map of cellular targets of BMP signaling in the developing kidney. We find that SMAD dependent BMP signaling is active in collecting duct trunks, but not tips. Furthermore, glomerular endothelial cells, and proximal nephron tubules from the renal vesicle stage onward show pathway activation. Surprisingly, little activation is detected in the nephrogenic zone of the kidney, and in organ culture BMP treatment fails to activate SMAD dependent BMP signaling in nephron progenitor cells. In contrast, signaling is efficiently induced in collecting duct tips.

Conclusion

Transgenic reporters driven by control elements from BMP responsive genes such as Id1 offer significant advantages in sensitivity and consistency over immunostaining for studies of BMP pathway activation. They also provide opportunities for analysis of BMP signaling in organ and primary cell cultures subjected to experimental manipulation. Using such a reporter, we made the surprising finding that SMAD dependent BMP signaling is inactive in nephron progenitors, and that these cells are refractory to activation by applied growth factors. Furthermore, we find that the BMP pathway is not normally active in collecting duct tips, but that it can be ectopically activated by BMP treatment, offering a possible explanation for the inhibitory effects of BMP treatment on collecting duct growth and branching.
Interspecies data mining to predict novel ING-protein interactions in human
Authors: Gordon Paul MK , Soliman Mohamed A , Bose Pinaki , Trinh Quang , Sensen Christoph W , Riabowol Karl
Published: September 2008

Background

The IN hibitor of G rowth (ING) family of type II tumor suppressors (ING1–ING5) is involved in many cellular processes such as cell aging, apoptosis, DNA repair and tumorigenesis. To expand our understanding of the proteins with which the ING proteins interact, we designed a method that did not depend upon large-scale proteomics-based methods, since they may fail to highlight transient or relatively weak interactions. Here we test a cross-species (yeast, fly, and human) bioinformatics-based approach to identify potential human ING-interacting proteins with higher probability and accuracy than approaches based on screens in a single species.

Results

We confirm the validity of this screen and show that ING1 interacts specifically with three of the three proteins tested; p38MAPK, MEKK4 and RAD50. These novel ING-interacting proteins further link ING proteins to cell stress and DNA damage signaling, providing previously unknown upstream links to DNA damage response pathways in which ING1 participates. The bioinformatics approach we describe can be used to create an interaction prediction list for any human proteins with yeast homolog(s).

Conclusion

None of the validated interactions were predicted by the conventional protein-protein interaction tools we tested. Validation of our approach by traditional laboratory techniques shows that we can extract value from the voluminous weak interaction data already elucidated in yeast and fly databases. We therefore propose that the weak (low signal to noise ratio) data from large-scale interaction datasets are currently underutilized.
Prevalence of variations in melanoma susceptibility genes among Slovenian melanoma families
Authors: Peric Barbara , Cerkovnik Petra , Novakovic Srdjan , Zgajnar Janez , Besic Nikola , Hocevar Marko
Published: September 2008

Background

Two high-risk genes have been implicated in the development of CM (cutaneous melanoma). Germline mutations of the CDKN2A gene are found in < 25% of melanoma-prone families and there are only seven families with mutation of theCDK4gene reported to date. Beside those high penetrance genes, certain allelic variants of theMC1Rgene modify the risk of developing the disease.

The aims of our study were: to determine the prevalence of germlineCDKN2Amutations and variants in members of families with familial CM and in patients with multiple primary CM; to search for possibleCDK4mutations, and to determine the frequency of variations in theMC1Rgene.

Methods

From January 2001 until January 2007, 64 individuals were included in the study. The group included 28 patients and 7 healthy relatives belonging to 25 families, 26 patients with multiple primary tumors and 3 children with CM. Additionally 54 healthy individuals were included as a control group. Mutations and variants of the melanoma susceptibility genes were identified by direct sequencing.

Results

Seven families with CDKN2A mutations were discovered (7/25 or 28.0%). The L94Q mutation found in one family had not been previously reported in other populations. The D84N variant, with possible biological impact, was discovered in the case of patient without family history but with multiple primary CM. Only one mutation carrier was found in the control group. Further analysis revealed that c.540C>T heterozygous carriers were more common in the group of CM patients and their healthy relatives (11/64 vs. 2/54). One p14ARF variant was discovered in the control group and no mutations of theCDK4gene were found.

Most frequently found variants of theMC1Rgene were T314T, V60L, V92M, R151C, R160W and R163Q with frequencies slightly higher in the group of patients and their relatives than in the group of controls, but the difference was statistically insignificant.

Conclusion

The present study has shown high prevalence of p16INK4A mutations in Slovenian population of familial melanoma patients (37%) and an absence of p14ARF orCDK4mutations.
A population-based study of race-specific risk for placental abruption
Authors: Shen Tammy T , DeFranco Emily A , Stamilio David M , Chang Jen Jen , Muglia Louis J
Published: September 2008

Background

Efforts to elucidate risk factors for placental abruption are imperative due to the severity of complications it produces for both mother and fetus, and its contribution to preterm birth. Ethnicity-based differences in risk of placental abruption and preterm birth have been reported. We tested the hypotheses that race, after adjusting for other factors, is associated with the risk of placental abruption at specific gestational ages, and that there is a greater contribution of placental abruption to the increased risk of preterm birth in Black mothers, compared to White mothers.

Methods

We conducted a population-based cohort study using the Missouri Department of Health's maternally-linked database of all births in Missouri (1989–1997) to assess racial effects on placental abruption and the contribution of placental abruption to preterm birth, at different gestational age categories (n = 664,303).

Results

Among 108,806 births to Black mothers and 555,497 births to White mothers, 1.02% (95% CI 0.96–1.08) of Black births were complicated by placental abruption, compared to 0.71% (95% CI 0.69–0.73) of White births (aOR 1.32, 95% CI 1.22–1.43). The magnitude of risk of placental abruption for Black mothers, compared to White mothers, increased with younger gestational age categories. The risk of placental abruption resulting in term and extreme preterm births (< 28 weeks) was higher for Black mothers (aOR 1.15, 95% CI 1.02–1.29 and aOR 1.98, 95% CI 1.58–2.48, respectively). Compared to White women delivering in the same gestational age category, there were a significantly higher proportion of placental abruption in Black mothers who delivered at term, and a significantly lower proportion of placental abruption in Black mothers who delivered in all preterm categories (p < 0.05).

Conclusion

Black women have an increased risk of placental abruption compared to White women, even when controlling for known coexisting risk factors. This risk increase is greatest at the earliest preterm gestational ages when outcomes are the poorest. The relative contribution of placental abruption to term births was greater in Black women, whereas the relative contribution of placental abruption to preterm birth was greater in White women.
Can colorectal cancer mass-screening organization be evidence-based? Lessons from failures: The experimental and pilot phases of the Lazio program
Authors: Federici Antonio , Barca Alessandra , Baiocchi Diego , Quadrino Francesco , Valle Sabrina , Borgia Piero , Guasticchi Gabriella , Giorgi Rossi Paolo ,   The Colon-Rectal Cancer Screening Working Group
Published: September 2008

Background

Screening programmes should be organized to translate theoretical efficacy into effectiveness. An evidence-based organizational model of colorectal cancer screening (CRCS) should assure feasibility and high compliance.

Methods

A multidisciplinary Working Group (WG), reviewed literature and guidelines to define evidence-based recommendations. The WG identified the need for further local studies: physicians' CRCS attitudes, the effect of test type and provider on compliance, and individual reasons for non-compliance. A survey of digestive endoscopy services was conducted. A feasibility study on a target population of 300.000 has begun.

Results

Based on the results of population trials and on literature review the screening strategy adopted was Faecal Occult Blood Test (FOBT) every two years for 50–74 year olds and, for positives, colonoscopy. The immunochemical test was chosen because it has 20% higher compliance than the Guaiac. GPs were chosen as the preferred provider also for higher compliance. Since we observed that distance is the major determinant of non-compliance, we choose GPs because they are the closest providers, both geographically and emotionally, to the public.

The feasibility study showed several barriers: GP participation was low, there were administrative problems to involve GPs; opportunistic testing by the GPs; difficulties in access to Gastroenterology centres; difficulties in gathering colonoscopy results; little time given to screening activity by the gastroenterology centre.

Conclusion

The feasibility study highlighted several limits of the model. Most of the barriers that emerged were consequences of organisational choices not supported by evidence. The principal limit was a lack of accountability by the participating centres.
International medical graduates (IMGs) needs assessment study: comparison between current IMG trainees and program directors
Authors: Zulla Rachelle , Baerlocher Mark Otto , Verma Sarita
Published: September 2008

Background

International Medical Graduates (IMGs) training within the Canadian medical education system face unique difficulties. The purpose of this study was to explore the challenges IMGs encounter from the perspective of trainees and their Program Directors.

Methods

Program Directors of residency programs and IMGs at the University of Toronto were anonymously surveyed and asked to rate (using a 5-point Likert scale; 1 = least important – 5 = most important) the extent to which specific issues were challenging to IMGs and whether an orientation program (in the form of a horizontal curriculum) should be implemented for incoming IMGs prior to starting their residency.

Results

Among the IMGs surveyed, Knowledge of the Canadian Healthcare System received the highest mean score (3.93), followed by Knowledge of Pharmaceuticals and Hospital formularies (3.69), and Knowledge of the Hospital System (3.69). In contrast, Program Directors felt that Communication with Patients (4.40) was a main challenge faced by IMGs, followed by Communication with Team Members (4.33) and Basic Clinical Skills (4.28).

Conclusion

IMGs and Program Directors differ in their perspectives as to what are considered challenges to foreign-trained physicians entering residency training. Both groups agree that an orientation program is necessary for incoming IMGs prior to starting their residency program.
Health-related quality of life in infertile couples receiving IVF or ICSI treatment
Authors: Rashidi Batool , Montazeri Ali , Ramezanzadeh Fatemeh , Shariat Mamak , Abedinia Nasrin , Ashrafi Mahnaz
Published: September 2008

Background

Infertile couples might experience psychological distress and suffer from impaired health-related quality of life. This study aimed to examine health-related quality of life in infertile couples receiving either in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment.

Methods

This was a cross-sectional study of quality of life in infertile couples attending to Vali-e-Asr Reproductive Health Research Center or Royan Institute for either IVF or ICSI treatment in Tehran, Iran. Health-related quality of life was assessed using the Short Form Health Survey (SF-36). Patients' demographic and clinical characteristics were also recorded. Data were analyzed to compare quality of life in infertile women and men and to indicate what variables predict quality of life in infertile couples.

Results

In all 514 women and 514 men (n = 1028) were studied. There were significant differences between women and men indicating that male patients had a better health-related quality of life. Also health-related quality of life was found to be better in infertility due to male factor. Performing logistic regression analysis it was found that female gender, and lower educational level were significant predictors of poorer physical health-related quality of life. For mental health-related quality of life in addition to female gender and lower educational level, younger age also was found to be a significant predictor of poorer condition. No significant results were observed for infertility duration or causes of infertility either for physical or mental health-related quality of life.

Conclusion

The findings suggest that infertility duration or causes of infertility do not have significant effects on health-related quality of life in infertile couples. However, infertile couples, especially less educated younger women, are at risk of a sub-optimal health-related quality of life and they should be provided help and support in order to improve their health-related quality of life.
Paroxysmal Extreme Pain Disorder M1627K Mutation in Human Nav1.7 Renders DRG Neurons Hyperexcitable
Authors: Dib-Hajj Sulayman D , Estacion Mark , Jarecki Brian W , Tyrrell Lynda , Fischer Tanya Z , Lawden Mark , Cummins Theodore R , Waxman Stephen G
Published: September 2008

Background:

Paroxysmal extreme pain disorder (PEPD) is an autosomal dominant painful neuropathy with many, but not all, cases linked to gain-of-function mutations in SCN9A which encodes voltage-gated sodium channel Nav1.7. Severe pain episodes and skin flushing start in infancy and are induced by perianal probing or bowl movement, and pain progresses to ocular and mandibular areas with age. Carbamazepine has been effective in relieving symptoms, while other drugs including other anti-epileptics are less effective.

Results:

Sequencing of SCN9A coding exons from an English patient, diagnosed with PEPD, has identified a methionine 1627 to lysine (M1627K) substitution in the linker joining segments S4 and S5 in domain IV. We confirm that M1627K depolarizes the voltage-dependence of fast-inactivation without substantially altering activation or slow-inactivation, and inactivates from the open state with slower kinetics. We show here that M1627K does not alter development of closed-state inactivation, and that M1627K channels recover from fast-inactivation faster than wild type channels, and produce larger currents in response to a slow ramp stimulus. Using current-clamp recordings, we also show that the M1627K mutant channel reduces the threshold for single action potentials in DRG neurons and increases the number of action potentials in response to graded stimuli.

Conclusion:

M1627K mutation was previously identified in a sporadic case of PEPD from France, and we now report it in an English family. We confirm the initial characterization of mutant M1627K effect on fast-inactivation of Nav1.7 and extend the analysis to other gating properties of the channel. We also show that M1627K mutant channels render DRG neurons hyperexcitable. Our new data provide a link between altered channel biophysics and pain in PEPD patients.
Visualizing the actin cytoskeleton in living plant cells using a photo-convertible mEos::FABD-mTn fluorescent fusion protein
Authors: Schenkel Mike , Sinclair Alison M , Johnstone Daniel , Bewley JDerek , Mathur Jaideep
Published: September 2008

Background

The actin cytoskeleton responds quickly to diverse stimuli and plays numerous roles in cellular signalling, organelle motility and subcellular compartmentation during plant growth and development. Molecular and cell biological tools that can facilitate visualization of actin organization and dynamics in a minimally invasive manner are essential for understanding this fundamental component of the living cell.

Results

A novel, monomeric (m) Eos-fluorescent protein derived from the coral Lobophyllia hemprichii was assessed for its green to red photo-convertibility in plant cells by creating mEosFP-cytosolic. mEosFP was fused to the F-(filamentous)-Actin Binding Domain of the mammalian Talin gene to create mEosFP::FABDmTalin. Photo-conversion, visualization and colour quantification protocols were developed for EosFP targeted to the F-actin cytoskeleton. Rapid photo-conversion in the entire cell or in a region of interest was easily achieved upon illumination with an approximately 400 nm wavelength light beam using an epi-fluorescent microscope. Dual color imaging after photo-conversion was carried out using a confocal laser-scanning microscope. Time-lapse imaging revealed that although photo-conversion of single mEosFP molecules can be rapid in terms of live-cell imaging it involves a progressive enrichment of red fluorescent molecules over green species. The fluorescence of photo-converted cells thus progresses through intermediate shades ranging from green to red. The time taken for complete conversion to red fluorescence depends on protein expression level within a cell and the quality of the focusing lens used to deliver the illuminating beam. Three easily applicable methods for obtaining information on fluorescent intensity and colour are provided as a means of ensuring experimental repeatability and data quantification, when using mEosFP and similar photo-convertible proteins.

Conclusion

The mEosFP::FABD-mTn probe retains all the imaging qualities associated with the well tested GFP::mTn probe while allowing for non-invasive, regional photo-conversion that allows colour based discrimination within a living cell. Whereas a number of precautions should be exercised in dealing with photo-convertible probes, mEosFP::FABD-mTn is a versatile live imaging tool for dissecting the organization and activity of the actin cytoskeleton in plants.
Gas emission during laparoscopic colorectal surgery using a bipolar vessel sealing device: A pilot study on four patients
Authors: Hübner Martin , Sigrist Markus W , Demartines Nicolas , Gianella Michele , Clavien Pierre A , Hahnloser Dieter
Published: September 2008

Background

Dissection during laparoscopic surgery produces smoke containing potentially toxic substances. The aim of the present study was to analyze smoke samples produced during laparoscopic colon surgery using a bipolar vessel sealing device (LigaSure™).

Methods

Four consecutive patients undergoing left-sided colectomy were enrolled in this pilot study. Smoke was produced by the use of LigaSure™. Samples (5,5l) were evacuated from the pneumoperitoneum in a closed system into a reservoir. Analysis was performed with CO2-laser-based photoacoustic spectroscopy and confirmed by a Fourier-transform infrared spectrum. The detected spectra were compared to the available spectra of known toxins.

Results

Samples from four laparoscopic sigmoid resections were analyzed. No relevant differences were noted regarding patient and operation characteristics. The gas samples were stable over time proven by congruent control measurements as late as 24 h after sampling. The absorption spectra differed considerably between the patients. One broad absorption line at 100 ppm indicating H2O and several unknown molecules were detected. With a sensitivity of alpha min ca 10-5 cm-1 no known toxic substances like phenol or indole were identified.

Conclusion

The use of a vessel sealing device during laparoscopic surgery does not produce known toxic substances in relevant quantity. Further studies are needed to identify unknown molecules and to analyze gas emission under various conditions.
Bilateral parapelvic cysts that mimic hydronephrosis in two imaging modalities: a case report
Authors: Tarzamni Mohammad Kazem , Sobhani Narges , Nezami Nariman , Ghiasi Faramarz
Published: September 2008

Parapelvic cysts are uncommon conditions that are usually found during autopsy. Their ultrasonographic appearance is similar to hydronephrosis. We report the case of a 46-year-old female with a 4-year history of vague flank pain and a previous history of bilateral moderate hydronephrosis. The patient was investigated by ultrasonography and non-enhanced CT scan, and finally diagnosed as bilateral parapelvic cysts by a contrast-enhanced CT scan. For any patient with hydronephrosis detected by sonography, the possibility of parapelvic cysts should be kept in mind, especially if no underlying cause is detected and other routine imaging is inconsistent with hydronephrosis. In such circumstances a CT scan with contrast enhancement should not be refused, and relying on sonographic signs, previously mentioned in literatures, can be misleading.
Role of STAT4 polymorphisms in systemic lupus erythematosus in a Japanese population: a case-control association study of the STAT1-STAT4region
Authors: Kawasaki Aya , Ito Ikue , Hikami Koki , Ohashi Jun , Hayashi Taichi , Goto Daisuke , Matsumoto Isao , Ito Satoshi , Tsutsumi Akito , Koga Minori , Arinami Tadao , Graham Robert R , Hom Geoffrey , Takasaki Yoshinari , Hashimoto Hiroshi , Behrens Timothy W , Sumida Takayuki , Tsuchiya Naoyuki
Published: September 2008

Introduction

Recent studies identified STAT4 (signal transducers and activators of transcription-4) as a susceptibility gene for systemic lupus erythematosus (SLE). STAT1 is encoded adjacently to STAT4 on 2q32.2-q32.3, upregulated in peripheral blood mononuclear cells from SLE patients, and functionally relevant to SLE. This study was conducted to test whether STAT4 is associated with SLE in a Japanese population also, to identify the risk haplotype, and to examine the potential genetic contribution of STAT1. To accomplish these aims, we carried out a comprehensive association analysis of 52 tag single nucleotide polymorphisms (SNPs) encompassing the STAT1-STAT4 region.

Methods

In the first screening, 52 tag SNPs were selected based on HapMap Phase II JPT (Japanese in Tokyo, Japan) data, and case-control association analysis was carried out on 105 Japanese female patients with SLE and 102 female controls. For associated SNPs, additional cases and controls were genotyped and association was analyzed using 308 SLE patients and 306 controls. Estimation of haplotype frequencies and an association study using the permutation test were performed with Haploview version 4.0 software. Population attributable risk percentage was estimated to compare the epidemiological significance of the risk genotype among populations.

Results

In the first screening, rs7574865, rs11889341, and rs10168266 in STAT4 were most significantly associated (P < 0.01). Significant association was not observed for STAT1. Subsequent association studies of the three SNPs using 308 SLE patients and 306 controls confirmed a strong association of the rs7574865T allele (SLE patients: 46.3%, controls: 33.5%, P = 4.9 × 10-6, odds ratio 1.71) as well as TTT haplotype (rs10168266/rs11889341/rs7574865) (P = 1.5 × 10-6). The association was stronger in subgroups of SLE with nephritis and anti-double-stranded DNA antibodies. Population attributable risk percentage was estimated to be higher in the Japanese population (40.2%) than in Americans of European descent (19.5%).

Conclusions

The same STAT4 risk allele is associated with SLE in Caucasian and Japanese populations. Evidence for a role of STAT1 in genetic susceptibility to SLE was not detected. The contribution of STAT4 for the genetic background of SLE may be greater in the Japanese population than in Americans of European descent.
Different regulation of eosinophil activity in Crohn’s disease compared with ulcerative colitis
Authors: Lampinen Maria , Backman Marie , Winqvist Ola , Rorsman Fredrik , Rönnblom Anders , Sangfelt Per , Carlson Marie
Published: September 2008

The aim of this investigation was to study the involvement of eosinophil and neutrophil granulocytes in different stages of Crohn’s disease (CD) and ulcerative colitis (UC). Biopsy samples were taken from the right flexure of the colon and from the rectum in patients with active (n=12) and inactive colonic CD (n=7), patients with active (n=33) and inactive UC (n=24), and from control subjects (n=11). Cell suspensions from biopsies and blood were analyzed by flow cytometry with regards to activation markers and viability. Immunohistochemistry was used to evaluate cell number and degranulation. Blood eosinophils were cultured with Th1 and Th2 cytokines, and the expression of activity markers was assessed by flow cytometry. Eosinophil number, viability, and activity were increased during active CD and UC compared with controls. The activity, assessed as CD44 expression, tended to diminish during inactive CD but was increased further in quiescent UC. Neutrophil number and activity were increased only during inflammation in both diseases. Culture of blood eosinophils with IL-5 and IL-13 caused increased CD44 expression, whereas IL-5 and IFN-γ induced elevated CD69 expression. We observed different patterns of eosinophil activation in CD and UC, with the highest CD44 expression during quiescent UC. Our in vitro experiments with recombinant cytokines suggest that the diverse mechanisms of eosinophil activation in CD and UC are a result of different cytokine milieus (Th1 vs. Th2). In contrast, neutrophil activation reflects the disease activity in CD and UC, irrespective of Th cell skewing.
Thiazolidinediones Are Partial Agonists for the Glucocorticoid Receptor
Authors: Matthews L. , Berry A. , Tersigni M. , D'Acquisto F. , Ianaro A. , Ray D.
Published: September 2008

Although thiazolidinediones were designed as specific peroxisome proliferator-activated receptor (PPAR)-γ-ligands, there is evidence for some off-target effects mediated by a non-PPARγ mechanism. Previously we have shown that rosiglitazone has antiinflammatory actions not explicable by activation of PPARγ,but possibly by the glucocorticoid receptor (GR). Rosiglitazone induces nuclear translocation both of GR-green fluorescent protein, and endogenous GR in HeLa and U20S cells but with slower kinetics than dexamethasone. Rosiglitazone also induces GR phosphorylation (Ser211), a GR ligand-binding-specific effect. Rosiglitazone drives luciferase expression from a simple glucocorticoid-response element containing reporter gene in a GR-dependent manner (EC50 4 μm), with a similar amplitude response to the partial GR agonist RU486. Rosiglitazone also inhibits dexamethasone-driven reporter gene activity (IC50 2.9 μm) in a similar fashion to RU486, suggesting partial agonist activity. Importantly we demonstrate a similar effect in PPARγ-null cells, suggesting both GR dependence and PPARγ independence. Rosiglitazone also activates a GAL4-GR chimera, driving a upstream activating sequence promoter, demonstrating DNA template sequence independence and furthermore enhanced steroid receptor coactivator-1-GR interaction, measured by a mammalian two-hybrid assay. Both ciglitazone and pioglitazone, structurally related to rosiglitazone, show similar effects on the GR. The antiproliferative effect of rosiglitazone is increased in U20S cells that overexpress GR, suggesting a biologically important GR-dependent component of rosiglitazone action. Rosiglitazone is a partial GR agonist, affecting GR activation and trafficking to influence engagement of target genes and affect cell function. This novel mode of action may explain some off-target effects observed in vivo. Additionally, antagonism of glucocorticoid action may contribute to the antidiabetic actions of rosiglitazone.

Rosiglitazone, ciglitazone, and pioglitazone are partial glucocorticoid receptor (GR) agonists, affecting GR phosphorylation, subcellular trafficking, co-modulator recruitment, and transcription regulatory function independently of peroxisome proliferator-activated receptorã.
A Role for Notch Signaling in Stromal Survival and Differentiation during Prostate Development
Authors: Orr Brigid , Grace O. Cathal , Vanpoucke Griet , Ashley George R. , Thomson Axel A.
Published: September 2008

Notch1 signaling is involved in epithelial growth and differentiation of prostate epithelia, and we have examined the role that notch signaling plays in the stroma of the developing prostate. We initially observed expression of δ-like 1 (Dlk1) and Notch2 in gene profiling studies of prostatic mesenchyme, and anticipated that they might be expressed in a key subset of inductive mesenchyme. Using quantitative RT-PCR, Northern blotting, and whole mount in situ hybridization, we confirmed that both Dlk1 and Notch2 mRNAs showed a restricted expression pattern within subsets of the stroma during prostate development. Localization of Dlk1 and Notch2 proteins mirrored the transcript expression, and showed both distinct and overlapping expression patterns within the stroma. Dlk1 and Notch2 were coexpressed in condensed inductive mesenchyme of the ventral mesenchymal pad (VMP), and were partially colocalized in the smooth muscle (SM) layer of the urethral stroma. In addition, Dlk1 was not expressed in SM adjacent to the VMP in female urethra. The function of notch signaling was examined using organ cultures of prostate rudiments and a small molecule inhibitor of notch receptor activity. Inhibition of notch signaling led to a loss of stromal tissue in both prostate and female VMP cultures, suggesting that this pathway was required for stromal survival. Inhibition of notch signaling also led to changes in both epithelial and stromal differentiation, which was evident in altered distributions of SM α-actin and p63 in prostates grown in vitro. The effects of notch signaling upon the stroma were only evident in the presence of testosterone, in contrast to effects upon epithelial differentiation.

Studies on the expression of delta-like 1 homolog (Dlk1) and Notch 2 in prostatic mesenchyme shows that inhibition of notch signaling leads to defects in mesenchymal differentiation.
Central Leptin Regulates Total Ceramide Content and Sterol Regulatory Element Binding Protein-1C Proteolytic Maturation in Rat White Adipose Tissue
Authors: Bonzón-Kulichenko Elena , Schwudke Dominik , Gallardo Nilda , Moltó Eduardo , Fernández-Agulló Teresa , Shevchenko Andrej , Andrés Antonio
Published: September 2008

Obesity and type 2 diabetes are associated with insulin and leptin resistance, and increased ceramide contents in target tissues. Because the adipose tissue has become a central focus in these diseases, and leptin-induced increases in insulin sensitivity may be related to effects of leptin on lipid metabolism, we investigated herein whether central leptin was able to regulate total ceramide levels and the expression of enzymes involved in ceramide metabolism in rat white adipose tissue (WAT). After 7 d central leptin treatment, the total content of ceramides was analyzed by quantitative shotgun lipidomics mass spectrometry. The effects of leptin on the expression of several enzymes of the sphingolipid metabolism, sterol regulatory element binding protein (SREBP)-1c, and insulin-induced gene 1 (INSIG-1) in this tissue were studied. Total ceramide levels were also determined after surgical WAT denervation. Central leptin infusion significantly decreased both total ceramide content and the long-chain fatty acid ceramide species in WAT. Concomitant with these results, leptin decreased the mRNA levels of enzymes involved in de novo ceramide synthesis (SPT-1, LASS2, LASS4) and ceramide production from sphingomyelin (SMPD-1/2). The mRNA levels of enzymes of ceramide degradation (Asah1/2) and utilization (sphingomyelin synthase, ceramide kinase, glycosyl-ceramide synthase, GM3 synthase) were also down-regulated. Ceramide-lowering effects of central leptin were prevented by local autonomic nervous system denervation of WAT. Finally, central leptin treatment markedly increased INSIG-1 mRNA expression and impaired SREBP-1c activation in epididymal WAT. These observations indicate that in vivo central leptin, acting through the autonomic nervous system, regulates total ceramide levels and SREBP-1c proteolytic maturation in WAT, probably contributing to improve the overall insulin sensitivity.

Central leptin decreases total ceramide levels and prevents sterol regulatory element binding protein (SREBP-1C) proteolytic maturation in white adipose tissue, and probably, in this way, contributes to improve the overall insulin sensitivity.