Abstract P1-01-23: Increased Diagnostic Performance of Sentinel Lymph Node Biopsy Combined with Radiologic-pathologic Factors After Neoadjuvant Chemotherapy in Breast Cancer Patients with Cytologically Proven Node Metastasis at Diagnosis

Background: It is undetermined whether sentinel lymph node biopsy (SLNB) is feasible and accurate for predicting final nodal status after neoadjuvant chemotherapy (NCT) in breast cancer patients with cytologically proven node metastasis at the time of diagnosis, although currently completion node dissection is a standard surgical procedure for the management of axilla. The aim of this study was to investigate diagnostic performance of SLNB after NCT in this subgroup.

Methods: Of 374 patients with T1-T3 breast cancer who received NCT, 178 had initially biopsy proven axillary/supraclavicular metastasis and subsequently underwent SLNB using radioisotope alone followed by completion node dissection between 2008 and 2011. Detection rate, sensitivity, false negative rate (FNR), negative predictive value (NPV), and accuracy of SLNB were retrospectively analyzed and it was explored using regression analysis whether combination with clinicopathologic factors improved performance.

Results: At initial presentation, 60.7% of patients were cT2 stage and 88.2% treated with concurrent or sequential anthracycline plus taxane preoperatively. SLNB was successfully performed in 169 (94.9%) patients. The mean number of sentinel and regional nodes retrieved was 2.1 ± 1.6 and 12.8 ± 6.3, respectively. Tumoral non-responder and extensive residual nodal disease were significantly associated with detection failure of SLNB. Conversion to node-negative disease was noted in 69 (40.8%) patients. Sensitivity, FNR, NPV, and accuracy of SLNB were 78.0%, 22.0%, 75.8%, and 87.0%, respectively and diagnostic performance increased when ≥ 3 sentinel nodes were evaluated. By logistic regression model, tumoral and nodal responder, absent lymphovascular invasion (LVI), estrogen receptor (ER)-negativity, and HER2-positivity were significantly associated with node-negative disease after NCT. Area under the receiver operating characteristic curve increased from 0.890 to 0.949 when considering radiologic-pathologic factors and FNR was the lowest value of 14.3% in 46 patients with tumoral responder, absent LVI, and ER-negative tumor.

Conclusions: SLNB was technically feasible but solely showed higher FNR in this study. Improved diagnostic performance of SLNB combined with radiologic-pathologic characteristics suggests possible clinical value of SLNB after NCT in highly selected patients with node metastasis at diagnosis.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-01-23.

Abstract P2-05-03: Mouse double minute 2 nuclear expression as a prognostic marker in patients with breast cancer

BACKGROUND: Mouse double minute 2 (Mdm2) is a negative regulator of tumor suppressor, p53, thus Mdm2 expression may play a role in cancer development and prognosis, however, the definite role of Mdm2 in breast cancer is unclear. The aim of the study is to evaluate the correlation between Mdm2 expression and prognosis of breast cancer.

METHODS: Mdm2 expression was determined from immunohistochemistry of tissue microarrays of 865 patients with breast cancer who underwent surgery. Clinicopathologic characteristics and survival data were analyzed using a univariate and multivariate analysis. Mdm2 expression was categorized into 3 groups: negative; no Mdm2 expression in nucleus and cytoplasm, cytoplasm-positive; cytoplasmic expression of Mdm2, nucleus-positive; nuclear with or without cytoplastimc expression of Mdm2.

RESULTS: Negative, cytoplasm-positive, and nucleus-positive groups were observed in 59.2%, 10.9%, and 29.9% of patients, respectively. Nucleus-positive group was associated with young age, high grade, negativity of estrogen and progesterone receptor, HER2 positivity, and high Ki-67 index. With median 86.0 follow-up months, nucleus-positive group showed poorer disease-free survival and overall survival than negative and cytoplasm-positive groups. In multivariate analysis, cytoplsmic expression of Mdm2 was not significantly associated with survival, whereas nuclear expression of Mdm2 was related to poor prognosis. (HR, 1.44; 95% CI, 1.041–1.993 for DFS; HR, 1.546; 95% CI, 1.060–2.255 for OS)

CONCLUSIONS: Nuclear expression of Mdm2 was an independent prognostic factor in patients with breast cancer. Patterns of Mdm2 expression in tumor cell should be rendered in the evaluation of Mdm2 in breast cancer.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-03.

Elevated levels of preoperative CA 15-3 and CEA serum levels have independently poor prognostic significance in breast cancer

BACKGROUND

To evaluate the prognostic value of preoperative tumor markers, cancer antigen 15-3 (CA 15-3) and carcinoembryonic antigen (CEA), in breast cancers.

PATIENTS AND METHODS

Preoperative CA 15-3 and CEA levels of 1681 patients were measured. The association of both tumor markers levels with clinicopathological parameters and outcomes was investigated by univariate and multivariate analyses.

RESULTS

Among 1681 patients, elevated preoperative CA15-3 and CEA levels were identified in 176 and 131 patients, respectively. Higher preoperative CA 15-3 and CEA levels were significantly associated with a larger tumor size, axillary node metastases, and advanced stage. Patients with elevated CA 15-3 and CEA levels showed worse survival, even in stage-matched analysis. Patients with normal levels of both CA15-3 and CEA showed better survival than those with one or both markers levels elevated. In multivariate analysis, elevated preoperative CA 15-3 and CEA levels were independent prognostic factors. The statistical significance of elevated preoperative tumor markers levels on survival was solidified with longer follow-up and larger study population.

CONCLUSIONS

Elevated preoperative CA 15-3 and CEA levels are associated with tumor burden and showed independent prognostic significance. Therefore, new treatment strategies are necessary for patients with elevated preoperative CA 15-3 and CEA levels in clinical practice.

Predicting portal hypertension as assessed by acoustic radiation force impulse: correlations with the Doppler ultrasound

OBJECTIVE

The purpose of this study was to assess the value of acoustic radiation force impulse (ARFI) for evaluating portal hypertension by correlating the elasticity of liver cirrhosis, as measured by ARFI, with haemodynamic indices measured by Doppler ultrasound.

METHODS

We evaluated the data of a total of 154 prospectively enrolled patients who underwent both duplex Doppler ultrasound and ARFI imaging. The duplex Doppler ultrasound indices, including the mean portal vein velocity, splenic index (SI) and splenoportal index (SPI) were evaluated to determine the statistical correlation with shear wave velocity (SWV) of ARFI. We also analysed the differences in the correlations between the SI, SPI and SWV of the group who had varices. The correlations were assessed with Spearman's rank correlation coefficients.

RESULTS

There was an increase of SWV in parallel with the increase of the SI (ρ=0.409, p<0.01) and SPI (ρ=0.451, p<0.01). In the patient group who did not have varices (n=74), the Doppler indices were found to be more correlated with the SWV (SI: ρ=0.447, SPI: ρ=0.552, p<0.01). However, the group with varices showed no correlation between the SWV and the Doppler parameters.

CONCLUSION

SWV of ARFI was well correlated statistically with Doppler parameters, but is of limited value in predicting portal hypertension directly owing to great variability of Doppler parameters. By evaluating the correlation between ARFI and Doppler ultrasound, we suggest that the SWV might be a non-invasive supplementary tool for predicting portal hypertension.

Proteins involved in DNA damage response pathways and survival of stage I non-small-cell lung cancer patients

BACKGROUND

Biological complexity leads to significant variation in the survival of patients with stage I non-small-cell lung cancer (NSCLC). DNA damage response (DDR) pathways play a critical role in maintaining genomic stability and in the progression of NSCLC. Therefore, the development of a prognostic biomarker focusing on DDR pathways is an intriguing issue.

PATIENTS AND METHODS

Expression of several proteins (ATM, ATMpS1981, γH2AX, 53BP1, 53BP1pS25, Chk2, Chk2pT68, MDC1, MDC1pS964, BRCA1pS1423, and ERCC1) and overall survival were investigated in 889 pathological stage I NSCLC patients.

RESULTS

Low expression of BRCA1pS1423 or ERCC1 was significantly associated with worse survival in the whole cohort of patients. Analysis performed based on histology revealed that low expression of γH2AX, Chk2pT68, or ERCC1 was a poor prognostic factor in squamous cell carcinoma patients [adjusted hazard ratio (aHR), Cox P: 1.544, 0.012 for γH2AX; 1.624, 0.010 for Chk2pT68; 1.569, 0.011 for ERCC1]. The analysis of the interaction between two proteins showed that this effect was more pronounced in squamous cell carcinoma patients. However, these effects were not detected in adenocarcinoma patients.

CONCLUSIONS

The proteins involved in DDR pathways exhibited differential expression between squamous cell carcinoma and adenocarcinoma and were important determinants of survival in stage I squamous cell carcinoma patients.

POZ/BTB and AT-hook-containing zinc finger protein 1 (PATZ1) inhibits endothelial cell senescence through a p53 dependent pathway

Vascular cell senescence, induced by the DNA damage response or inflammatory stress, contributes to age-associated vascular disease. Using complementary DNA microarray technology, we found that the level of POZ/BTB and AT-hook-containing zinc finger protein 1 (PATZ1) is downregulated during endothelial cell (EC) senescence. PATZ1 may have an important role as a transcriptional repressor in chromatin remodeling and transcription regulation; however, the role of PATZ1 in EC senescence and vascular aging remains unidentified. Knockdown of PATZ1 in young cells accelerated premature EC senescence, which was confirmed by growth arrest, increased p53 protein level and senescence-associated β-galactosidase (SA-β-gal) activity, and repression of EC tube formation. In contrast, overexpression of PATZ1 in senescent cells reversed senescent phenotypes. Cellular senescence induced by PATZ1 knockdown in young cells was rescued by knockdown of p53, but not by knockdown of p16(INK4a). PATZ1 knockdown increased ROS levels, and pretreatment with N-acetylcysteine abolished EC senescence induced by PATZ1 knockdown. Notably, PATZ1 immunoreactivity was lower in ECs of atherosclerotic tissues than those of normal arteries in LDLR(-/-) mice, and immunoreactivity also decreased in ECs of old human arteries. These results suggest that PATZ1 may have an important role in the regulation of EC senescence through an ROS-mediated p53-dependent pathway and contribute to vascular diseases associated with aging.

The evaluation of soybean meals from 3 major soybean-producing countries on productive performance and feeding value of pig diets

This study was conducted to evaluate 1) the effects of soybean meal (SBM) from 3 major SBM-producing countries (United States, Brazil, and India) on the growth performance, nutrient digestibility, and meat quality of growing-finishing pigs and 2) the feeding value of the evaluated SBM as a feedstuff for growing-finishing pigs. Soybean meal representative of each country was purchased on the open market. A total of 144 barrows with the average BW of 23.77 (SD = 1.52 kg) were allotted to 3 dietary treatments with 12 replicate pens per treatment and 4 pigs per pen. The US SBM used in this trial had greater CP and total AA contents, greater KOH protein solubility, and less crude fiber than SBM from either Brazil or India. Diets were formulated to be isolysinic and isocaloric. Pigs fed diets containing US SBM were heavier (P < 0.05) than pigs fed diets containing Brazilian or Indian SBM at 12 and 18 wk. Pigs fed diets containing US SBM had greater (P < 0.05) ADG and G:F throughout the overall period when compared with pigs fed SBM produced in Brazil or India. The DM and N digestibility were greater for US SBM (P < 0.05) than Brazilian and India SBM at 6, 12, and 18 wk. Pigs were slaughtered at the end of 18 wk, and no differences were observed on meat quality (backfat thickness, LM area, pH, meat color, water holding capacity, and drip loss) among the treatments, except lean percentages were less and backfat thickness was greater in pigs fed Brazilian and Indian SBM than US SBM. The cost per kilogram of BW gain of the experimental diet containing US SBM was less than that of diets containing Brazilian or Indian SBM, but it would depend on the relative prices of each SBM. Based on the results of the current experiment, the productivity and feeding value of US SBM seems to be greater than the SBM produced in Brazil and India.

Effect of dietary fermented garlic by Weissella koreensis powder on growth performance, blood characteristics, and immune response of growing pigs challenged with Escherichia coli lipopolysaccharide

Two experiments were conducted to investigate the effect of fermented garlic by Weissella koreensis powder (WKG) on pig growth performance and immune responses after an Escherichia coli lipopolysaccharide (LPS) challenge. In Exp. 1, 120 growing barrows (23.5 ± 0.5 kg of BW and 56 d of age) were used in a 35-d experiment to determine the optimal amounts of WKG. Pigs were randomly allotted to 1 of 5 treatments with 6 replicate pens and 4 pigs per pen. Dietary treatments included 1) NC (negative control; basal diet without antibiotics), 2) PC (positive control; basal diet + 1 g of tylosin/kg), 3) WKG1 (basal diet + 1 g of WKG/kg), 4) WKG2 (basal diet + 2 g of WKG/kg), and 5) basal diet + 4 g of WKG/kg. At the end of the feeding period, 12 pigs each were selected from the NC and WKG2 treatment groups, and 6 pigs were injected with LPS (50 μg/kg of BW) and the other 6 pigs with an equivalent amount of sterile saline, resulting in a 2 × 2 factorial arrangement of treatments. Blood samples and rectal temperature data were collected at 0, 2, 4, 6, 8, and 12 h after challenge. The ADG of pigs fed WKG- and antibiotic-supplemented diets was greater (P<0.05) than NC from d 14 to 35 and the overall phase, but no dosage-dependent effects were observed. At the end of the experiment, the fecal E. coli count was linearly reduced by the increasing amounts of WKG at d 35 (P=0.01). Challenge with LPS increased white blood cell counts at 6 and 8 h (P<0.01) and depressed lymphocyte concentration at 4, 8, and 12 h (P<0.01). During challenge, LPS injection increased rectal temperature at 2, 4, 6, and 8 h postchallenge (P<0.05), and WKG2 alleviated (P<0.05) the increase in the temperature at 2 h postchallenge. The LPS injection increased plasma tumor necrosis factor-α and IGF-1 concentrations at 2, 4, 6, 8, and 12 h (P<0.01), whereas an alleviating effect of WKG was observed at 4, 6, and 8 h after LPS challenge (P<0.05). At 2, 4, and 6 h postchallenge, concentration of cluster of differentiation-antigen-4-positive cells and cluster of differentiation-antigen-8-positive cells (CD4(+) and CD8(+), respectively) increased in the LPS treatments (P<0.05), and the WKG2 boosted this effect (P<0.05). In conclusion, dietary supplementation of WKG2 in growing pigs can improve ADG and have a beneficial effect on the immune response during an inflammatory challenge.

Pregnenolone sulfate enhances spontaneous glutamate release by inducing presynaptic Ca2+-induced Ca2+ release

Pregnenolone sulfate (PS) acts as an excitatory neuromodulator and has a variety of neuropharmacological actions, such as memory enhancement and convulsant effects. In the present study, we investigated the effect of PS on glutamatergic spontaneous excitatory postsynaptic currents (sEPSCs) in acutely isolated dentate gyrus (DG) hilar neurons by use of a conventional whole-cell patch-clamp technique. PS significantly increased sEPSC frequency in a concentration-dependent manner without affecting the current amplitude, suggesting that PS acts presynaptically to increase the probability of spontaneous glutamate release. However, known molecular targets of PS, such as α7 nicotinic ACh, NMDA, σ1 receptors and voltage-dependent Ca(2+) channels, were not responsible for the PS-induced increase in sEPSC frequency. In contrast, the PS-induced increase in sEPSC frequency was completely occluded in a Ca(2+)-free external solution, and was significantly reduced by either the depletion of presynaptic Ca(2+) stores or the blockade of ryanodine receptors, suggesting that PS elicits Ca(2+)-induced Ca(2+) release (CICR) within glutamatergic nerve terminals. In addition, the PS-induced increase in sEPSC frequency was completely occluded by transient receptor potential (TRP) channel blockers. These data suggest that PS increases spontaneous glutamate release onto acutely isolated hilar neurons via presynaptic CICR, which was triggered by the influx of Ca(2+) through presynaptic TRP channels. The PS-induced modulation of excitatory transmission onto hilar neurons could have a broad impact on the excitability of hilar neurons and affect the pathophysiological functions mediated by the hippocampus.

Effects of electric voltage and sodium chloride level on electrolysis of swine wastewater

The effects of electric voltage and NaCl concentration on the removal of pollutants in swine wastewater were investigated to determine the optimum operation conditions for a designed electrolysis process. An up-flow electrolytic reactor was fabricated from Plexiglas, and one titanium anode coated with iridium oxide (IrO(2)) and two stainless steel cathodes were installed in it. The anode surface area was 80 cm(2)/L and the hydraulic retention time (HRT) was 6h. The results indicated that the pollutant removal was highly proportional to the electric voltage and removal could be enhanced by adding NaCl. The removal efficiencies of NH(4)-N, soluble nitrogen (NH(4)-N plus NO(x)-N), soluble total organic carbon (STOC), and color were proportional to the NaCl level up to 0.05% NaCl level, beyond which no further enhancement in removal was observed. However, such a tendency was not observed in the case of PO(4)-P removal. The obtained results indicate that 7 V and 0.05% (8.56 mM) NaCl level would be the optimum conditions for the designed electrolysis process. Under these conditions, the average removal efficiencies of NH(4)-N, soluble nitrogen, PO(4)-P, STOC, and color were 99%, 94%, 59%, 64%, and 93%, respectively.

Kelvin probe force microscopy for conducting nanobits of NiO thin films

We demonstrated the writing and reading of conducting nanobits on a NiO thin film deposited on Pt/TiO(2)/SiO(2)/Si substrates for a resistive random access memory (RRAM) application using conducting atomic force microscopy (CAFM) and Kelvin probe force microscopy (KFM). A Pt/NiO/Pt RRAM capacitor showed a typical unipolar switching behavior with bistable resistances. Conducting nanobits with diameters of 22 nm written with a bias of 3.0 V on the NiO thin film were observed with CAFM. The conducting nanobits observed by KFM exhibited negative potentials relative to the insulating regions when there was no bias at the Pt bottom electrode because image charges were induced by charges formed at the end of the KFM tip by the reference AC bias. Enhancement of the KFM signals for conducting nanobits was achieved using specific biases at the Pt bottom electrode, which provided clear KFM images for conducting nanobits.

Atypical radiological features of a leiomyosarcoma that arose from the ovarian vein and mimicked a vascular tumour

Leiomyosarcomas of the ovarian vein are extremely rare tumours. Most tumours are hypervascular and typically have a large avascular centre of necrosis. We experienced a case of a retroperitoneal leiomyosarcoma that arose from the ovarian vein with marked vascular proliferation and dilatation within the tumour. To the best of our knowledge, this is the first case report of a retroperitoneal leiomyosarcoma with an atypical vascular structure in the clinical literature.

Characteristics of DOC concentration with storm density flows in a stratified dam reservoir

Among natural organic matter (NOM) defined as the complex matrix of organic materials abundant in natural waters, a gradual accumulation of recalcitrant organic matter (ROM) has been observed in impounded water bodies such as a lake or dam reservoir in spite of extensive efforts made to curtail organic pollutant loadings generated in their catchment areas. This paper aims to identify the effect of diffuse pollution resulting from allochthonous organic matters on the temporal and spatial characteristics of organic matters in a stratified dam reservoir, Daecheong Dam, using both intensive observation and CE-QUAL-W2 model simulation. With the limitation of observation data in terms of organic matters of inflow waters from boundary tributaries and impounded water in the reservoir, organic matter was represented by organic carbon including labile particular organic carbon (LPOC), refractory organic carbon (RPOC), labile dissolved organic carbon (LDOC), and refractory organic carbon (RDOC). Both autochthonous and allochthonous origins of organic carbon were considered in the modeling of eutrophication of the reservoir water using CE-QUAL-W2. The result of simulation during the period from 2001 to 2005 was observed to be a gradual accumulation of particular organic carbon (POC). It is clear that the model calculation results enable the explanation of the internal and external movement of constituents in the reservoir. In particular turbidity and NOM were well related in the upper region of the reservoir according to flow distance, gradually changing to dissolved form of organic matter, DOC affected organic matter concentration of reservoir water quality compared to turbidity.

A national survey on the practice and outcomes of mechanical ventilation in Korean intensive care units

A study was undertaken to describe the practice and outcomes of mechanical ventilation throughout Korea. This prospective cohort study was conducted over a three-month period enrolling patients (n = 519) who received mechanical ventilation for more than 72 hours in 21 university hospital intensive care units throughout Korea. The most common indication for mechanical ventilation was acute respiratory failure. The most common cause of acute-on-chronic respiratory failure was tuberculous lung disease. The most common initial mode for ventilation was volume-controlled ventilation. The mean tidal volume of acute respiratory distress syndrome patients was 7.6 ml/kg of the predicted body weight and the mean positive end-expiratory pressure was 9.4 cmH20. The weaning success rate at 28 days was 50.3%. Pressure support and the T-piece were most commonly used as initial and final weaning modes respectively. Preventive measures against deep vein thrombosis during mechanical ventilation were performed more frequently in intensive care units with full-time critical care physicians than those without such physicians. Multivariate analysis showed that the APACHE II score, indication for mechanical ventilation, respiratory rate at 72 hours, enteral feeding and prophylaxis of deep vein thrombosis were prognostic factors for survival. In Korean intensive care units, tuberculous lung disease remains an important cause for mechanical ventilation. The practice of mechanical ventilation in Korean intensive care units in general appeared to comply with the current international recommendations with regard to lung protection and weaning. However, intensive care units lacking critical care physicians seemed to be adopting fewer ancillary measures, such as deep vein thrombosis prophylaxis.

Preparation of biopolymer-coated magnetite nanoparticles for magnetic resonance image contrast agent

The magnetite nanoparticles were synthesized using the sonochemical method with oleic acid as surfactant. The average size of the magnetite particles can be controlled by the ratio R = [H2O]/[surfactant] in the range of 2 to 9 nm. The size of the magnetite nanoparticles prepared by this method shows the narrow distribution. To prepare biopolymer(beta-glucan)-coated magnetite nanoparticles, beta-glucan solution was added to the magnetic colloid suspensions under the ultrasonication at room temperature. The beta-glucan coated magnetite colloidal suspensions of various concentrations did not agglomerate for 15 days, indicating their good stability. The beta-glucan-coated magnetite colloidal suspensions exhibited the enhancement of MRI contrasts in vitro.

Cardiovascular autonomic dysfunction predicts acute ischaemic stroke in patients with Type 2 diabetes mellitus: a 7-year follow-up study

AIMS

We investigated whether cardiovascular autonomic neuropathy (CAN) is associated with acute ischaemic stroke in patients with Type 2 diabetes.

METHODS

From 1999 to 2000, cardiovascular autonomic function tests were conducted in patients with Type 2 diabetes (n = 1458). Patients were followed up between 2006 and 2007. Standard tests for CAN measured heart rate variability parameters [expiration-to-inspiration (E/I) ratio, responses to the Valsalva manoeuvre and standing]. Using the American Diabetes Association criteria, the CAN scores were determined from the results of each test as follows: 0 = normal, 1 = abnormal (total maximum score 3). We assessed the development of acute ischaemic stroke events.

RESULTS

The prevalence of CAN at baseline was 55.7% (E/I 17.1%, Valsalva 39.4%, posture 27.3%) (n = 1126). During follow-up, 131 patients (11.6%) developed acute ischaemic stroke. The vascular events were more frequent in older patients (P < 0.001) and in those with diabetes of longer duration (P = 0.022), hypertension (P < 0.001) or diabetic retinopathy (P = 0.03) than in patients without vascular events. Patients with ischaemic stroke had higher creatinine levels (P = 0.045) and higher urine albumin excretion (P = 0.025) than those of patients without stroke. Cox proportional hazard regression analysis revealed that the CAN score was associated with the development of acute ischaemic stroke (total score 0 vs. 3, adjusted hazard ratio 2.7, 95% CI 1.3-5.5, P = 0.006).

CONCLUSION

Cardiovascular autonomic dysfunction was significantly associated with the development of ischaemic stroke in patients with Type 2 diabetes.

MAST3: a novel IBD risk factor that modulates TLR4 signaling

Inflammatory bowel disease (IBD) is a chronic disorder caused by multiple factors in a genetically susceptible host. Significant advances in the study of genetic susceptibility have highlighted the importance of the innate immune system in this disease. We previously completed a genome-wide linkage study and found a significant locus (IBD6) on chromosome 19p. We were interested in identifying the causal variant in IBD6. We performed a two-stage association mapping study. In stage 1, 1530 single-nucleotide polymorphisms (SNPs) were selected from the HapMap database and genotyped in 761 patients with IBD. Among the SNPs that passed the threshold for replication, 26 were successfully genotyped in 754 additional patients (stage 2). One intronic variant, rs273506, located in the microtubule-associated serine/threonine-protein kinase gene-3 (MAST3), was found to be associated in both stages (pooled P=1.8 x 10(-4)). We identified four MAST3 coding variants, including a non-synonymous SNP rs8108738, correlated to rs273506 and associated with IBD. To test whether MAST3 was expressed in cells of interest, we performed expression assays, which showed abundant expression of MAST3 in antigen-presenting cells and in lymphocytes. The knockdown of MAST3 specifically decreased Toll-like receptor-4-dependent NF-kappaB activity. Our findings are additional proofs of the pivotal role played by modulators of NF-kappaB activity in IBD pathogenesis.

Gene-centric association mapping of chromosome 3p implicates MST1 in IBD pathogenesis

Association mapping and candidate gene studies within inflammatory bowel diseases (IBD) linkage regions, as well as genome-wide association studies in Crohn's disease (CD) have led to the discovery of multiple risk genes, but these explain only a fraction of the genetic susceptibility observed in IBD. We have thus been pursuing a region on chromosome 3p21-22 showing linkage to CD and ulcerative colitis (UC) using a gene-centric association mapping approach. We identified 12 functional candidate genes by searching for literature cocitations with relevant keywords and for gene expression patterns consistent with immune/intestinal function. We then performed an association study composed of a screening phase, where tagging single nucleotide polymorphisms (SNPs) were evaluated in 1,020 IBD patients, and an independent replication phase in 745 IBD patients. These analyses identified and replicated significant association with IBD for four SNPs within a 1.2 Mb linkage disequilibrium region. We then identified a non-synonymous coding variant (rs3197999, R689C) in the macrophage-stimulating 1 (MST1) gene (P-value 3.62 x 10(-6)) that accounts for the association signal, and shows association with both CD and UC. MST1 encodes macrophage-stimulating protein (MSP), a protein regulating the innate immune responses to bacterial ligands. R689C is predicted to interfere with MSP binding to its receptor, suggesting a role for this gene in the pathogenesis of IBD.

A facility for characterizing the steady-state and dynamic thermal performance of microelectromechanical system thermal switches

A facility to characterize microelectromechanical system (MEMS) thermal switches by measuring two pertinent figures of merit is described. The two figures of merit measured are the ratio of thermal resistance of the switch in the off and on states, Roff/Ron, and the time required to switch from the off to the on state, tauswitch. The facility consists of two pieces of equipment. A guard-heated calorimeter is used to measure heat transfer across the thermal switch under steady-state conditions. Measuring heat transfer across a thermal switch in both the off and on states then gives the thermal resistance ratio Roff/Ron. A thin-film radial heat-flux sensor is used to measure heat transfer across the thermal switch under dynamic conditions. Measuring heat transfer across a thermal switch as the switch changes from the off to the on state gives the thermal switching time tauswitch. The test facilities enable the control of the applied force on the thermal switch when the thermal switch is on, the thickness of the gas gap when the thermal switch is off, and the gas species and pressure in the thermal switch gas gap. The thermal performance of two MEMS thermal switches employing two different thermal contact materials, a polished silicon surface and an array of liquid-metal microdroplets, is characterized and compared.

An SNP linkage scan identifies significant Crohn's disease loci on chromosomes 13q13.3 and, in Jewish families, on 1p35.2 and 3q29

Inflammatory bowel disease (IBD) is a complex genetic disorder of two major phenotypes, Crohn's disease (CD) and ulcerative colitis (UC), with increased risk in Ashkenazi Jews. Twelve genome-wide linkage screens have identified multiple loci, but these screens have been of modest size and have used low-density microsatellite markers. We, therefore, performed a high-density single-nucleotide polymorphism (SNP) genome-wide linkage study of 993 IBD multiply affected pedigrees (25% Jewish ancestry) that contained 1709 IBD-affected relative pairs, including 919 CD-CD pairs and 312 UC-UC pairs. We identified a significant novel CD locus on chromosome 13p13.3 (peak logarithm of the odds (LOD) score=3.98) in all pedigrees, significant linkage evidence on chromosomes 1p35.1 (peak LOD score=3.5) and 3q29 (peak LOD score=3.19) in Jewish CD pedigrees, and suggestive loci for Jewish IBD on chromosome 10q22 (peak LOD score=2.57) and Jewish UC on chromosome 2q24 (peak LOD score=2.69). Nominal or greater linkage evidence was present for most previously designated IBD loci (IBD1-9), notably, IBD1 for CD families at chromosome 16q12.1 (peak LOD score=4.86) and IBD6 in non-Jewish UC families at chromosome 19p12 (peak LOD score=2.67). This study demonstrates the ability of high information content adequately powered SNP genome-wide linkage studies to identify loci not observed in multiple microsatellite-based studies in smaller cohorts.

Distal lenticulostriate artery aneurysm in deep intracerebral haemorrhage

Aneurysms of the distal lenticulostriate artery (LSA) are rare. Only 16 cases have been reported in the literature. Early detection and treatment of these aneurysms is also difficult because of their deep location, small size and angioarchitecture. We report two additional patients with aneurysms, arising from the distal LSA, who presented with deep intracerebral haemorrhage. The conclusions drawn from our experience and a comprehensive review of the literature include the following. (1) A distal LSA aneurysm should be considered in young (mean 38.5 years) and non-hypertensive (80%) patients with deep intracerebral haemorrhage. (2) These aneurysms are frequently very small (<5 mm). Therefore, they cannot be detected on initial angiograms in some cases. (3) These aneurysms have higher rates of associated vascular lesions. Deep intracerebral haemorrhage, even in those over the age of 50 years, can still be due to underlying, treatable structural abnormalities, and should not be dismissed as being a result of hypertension. In addition, a more comprehensive diagnostic approach seems to be warranted in younger patients and those without known hypertension.