IL-17RA-Mediated Epithelial Cell Activity Prevents Severe Inflammatory Response to Helicobacter pylori Infection

Helicobacter pylori is a Gram-negative pathogen that colonizes the stomach, induces inflammation, and drives pathological changes in the stomach tissue, including gastric cancer. As the principal cytokine produced by Th17 cells, IL-17 mediates protective immunity against pathogens by inducing the activation and mobilization of neutrophils. Whereas IL-17A is largely produced by lymphocytes, the IL-17 receptor is expressed in epithelial cells, fibroblasts, and hematopoietic cells. Loss of the IL-17RA in mice results in impaired antimicrobial responses to extracellular bacteria. In the context of H. pylori infection, this is compounded by extensive inflammation in Il17ra-/- mice. In this study, Foxa3creIl17rafl/fl (Il17raΔGI-Epi) and Il17rafl/fl (control) mice were used to test the hypothesis that IL-17RA signaling, specifically in epithelial cells, protects against severe inflammation after H. pylori infection. The data indicate that Il17raΔGI-Epi mice develop increased inflammation compared with controls. Despite reduced Pigr expression, levels of IgA increased in the gastric wash, suggesting significant increase in Ag-specific activation of the T follicular helper/B cell axis. Gene expression analysis of stomach tissues indicate that both acute and chronic responses are significantly increased in Il17raΔGI-Epi mice compared with controls. These data suggest that a deficiency of IL-17RA in epithelial cells is sufficient to drive chronic inflammation and hyperactivation of the Th17/T follicular helper/B cell axis but is not required for recruitment of polymorphonuclear neutrophils. Furthermore, the data suggest that fibroblasts can produce chemokines in response to IL-17 and may contribute to H. pylori-induced inflammation through this pathway.

Essential role of Helicobacter pylori apolipoprotein N-acyltransferase (Lnt) in stomach colonization

Bacterial lipoproteins are post-translationally modified with acyl chains, anchoring these proteins to bacterial membranes. In Gram-negative bacteria, three enzymes complete the modifications. Lgt (which adds two acyl chains) and LspA (which removes the signal peptide) are essential. Lnt (which adds a third acyl chain) is not essential in certain bacteria including Francisella tularensis, Neisseria gonorrhoeae, and Acinetobacter baumannii. Deleting lnt results in mild to severe physiologic changes. We previously showed lnt is not essential for Helicobacter pylori growth in vitro. Here, the physiologic consequences of deleting lnt in H. pylori and the role of Lnt in the host response to H. pylori were examined using in vitro and in vivo models. Comparing wild-type, Δlnt, and complemented mutant H. pylori, no changes in growth rates or sensitivity to acid or antibiotics were observed. Since deleting lnt changes the number of acyl chains on lipoproteins and the number of acyl chains on lipoproteins impacts the innate immune response through Toll-like receptor 2 (TLR2) signaling, primary human gastric epithelial cells were treated with a purified lipoprotein from wild-type or lnt mutant H. pylori. Differential gene expression analysis indicated that lipoprotein from the lnt mutant induced a more robust TLR2 response. In a complementary approach, we infected wild-type and Tlr2-/- mice and found that both the wild-type and complemented mutant strains successfully colonized the animals. However, the lnt mutant strain was unable to colonize either mouse strain. These results show that lnt is essential for H. pylori colonization and identifies lipoprotein synthesis as a target for therapeutic intervention.

P604Clinical feasibility assessment of a novel Quantitative Multi-contrast Atherosclerosis Characterization (qMATCH) sequence for carotid plaque quantification

Background

Conventional protocol contrast MRI (cMRI) for evaluating carotid artery atherosclerosis is clinically under-utilized due to complex scanning procedures and long scan time. Recently, the Quantitative Multi-contrast Atherosclerosis Characterization (qMATCH) has been proposed, which allows comprehensive and quantitative assessment of atherosclerosis including MRA, dark-blood vessel wall morphology, and T1/T2 mapping with an 8-minute single scan (Figure1). However, the diagnostic accuracy and feasibility of qMATCH has not been validated in clinical circumstances.

Purpose

To evaluate the diagnostic accuracy of quantitative plaque analysis of qMATCH compared with cMRI

Method

We prospectively enrolled 43 patients who have carotid plaques diagnosed by carotid ultrasound. cMRI was performed along with qMATCH scan. All imaging data were acquired with a clinical 3T scanner using a 64-channel head & neck coil. In the current analysis, we evaluated the diagnostic accuracy of qMATCH in the quantitative assessment of carotid plaque. Plaque area measurements using dark-blood wall images with qMATCH were compared with corresponding cross-sectional T1/T2-weighted images with cMRI as references values (Figure 2). These inter-technique comparisons included linear regression with Pearson correlation and Bland-Altman analyses to assess the mean inter-technique differences (biases) and limits of agreements.

Result

Among 90 segments, mean plaque areas measured by cMRI and qMATCH were 43.83±21.21 mm2 and 42.47±19.23mm2, respectively (mean differences, −1.36±8.12mm2; p for a paired t-test, 0.073). Correlation coefficient showed excellent correlation between plaque areas measured by cMRI and qMATCH (r=0.943, p<0.001) (Figure 3). Bland-Altman plot showed excellent agreement in plaque areas between the two methods (Figure 4).

Conclusion

Quantitative carotid plaque burden analysis by a novel sequence with qMATCH is feasible and accurate compared with conventional MRI. Given that qMATCH can reduce scan time and allow quantitative relaxometry mapping, fast and accurate carotid plaque analysis would be feasible. Further studies to evaluate the accuracy of qualitative plaque analysis should be performed to confirm the “all-in-one” assessment of carotid atherosclerosis using qMATCH.

Only the chemical state of Indium changes in Mn-doped In3Sb1Te2 (Mn: 10 at.%) during multi-level resistance changes

We fabricated and characterized the material with Mn (10 at.%: atomic percent) doped In3Sb1Te2 (MIST) using co-sputtering and synchrotron radiation, respectively. The MIST thin film showed phase-changes at 97 and 320 °C, with sheet resistances of ~10 kΩ(sq) (amorphous), ~0.2 kΩ(sq) (first phase-change), and ~10 Ω(sq) (second phase-change). MIST did not exhibit any chemical separation or increased structural instability during either phase-change, as determined with high-resolution x-ray photoelectron spectroscopy. Chemical state changes were only depended for In without concomitant changes of Sb and Te. Apparently, doped Mn atoms can be induced with movement of only In atoms.

Abstract S6-3: Neurocognitive impact in adjuvant chemotherapy for breast cancer linked to fatigue: A Prospective functional MRI study

Background: Our previous research showed evidence of compromised cognitive function prior to adjuvant chemotherapy for breast cancer, with fatigue as a contributory factor. Fatigue is a common symptom reported by women treated for breast cancer, yet its association with neurocognitive function has not been systematically examined. In this prospective study, we examined possible alterations in neurocognitive responses, namely, working memory, from pre- to post- adjuvant treatment during functional magnetic resonance imaging (fMRI) and further investigated whether early fatigue might be linked to cognitive alterations over time.

Methods: Women treated with either adjuvant chemotherapy (anthracyline-based combination regimen, n=29) or radiotherapy (n = 37) for localized breast cancer (Stages 0-IIIa) and age-matched healthy controls (n = 32) were enrolled. Participants performed a verbal working memory task (VWMT) with varying levels of demand for cognitive control during fMRI scanning and provided self-reports of fatigue (FACT-F) at two time points coincident with pre- and one-month post chemotherapy assessments. Imaging data were analyzed with general linear models using SPM5; comparative statistics were used to determine group differences, and correlational analyses addressed relationships of fatigue and neurocognitive measures.

Findings: The chemotherapy group reported significantly greater severity of fatigue (p &lt; .05) and performed less accurately on the VWMT both pre- and one-month post-treatment than the other groups. Greater fatigue was correlated with poorer performance on the VWMT at both time points across groups, with stronger correlation post-treatment (r = −.22, p = .03). A 2 time-point (pre- vs. post-treatment) × 2 group (chemotherapy vs. controls) × 2 demand-level contrasts (high minus low vs. medium minus low) analytic model showed a significant group × time interaction (p &lt; .05), mainly due to lower pre-treatment activation in an area of the prefrontal cortex supporting working memory, the anatomical left inferior frontal gyrus (LiFG), at higher task demand in the chemotherapy group. The radiotherapy group scored between the other two groups with intermediate activation of those contrasts. Of interest, lower pre-treatment activation in the LiFG in the high-low demand contrast predicted severity of fatigue across all participants at the post-treatment assessment (r = −.27, p &lt; .01), linking early compromise in neurocognitive performance with greater fatigue over time.

Discussion: Neurocognitive alterations during a working memory task and greater fatigue were evident before any adjuvant chemotherapy for breast cancer. Notably, functional alterations in working memory processes were evident with fMRI before adjuvant chemotherapy and predicted severity of post-treatment fatigue. Importantly, across all participants, greater fatigue over time was correlated with reduced cognitive performance. Taken together, these findings indicate that pre-treatment neurocognitive compromise and fatigue are key contributors to the cognitive impact often attributed solely to chemotherapy. Early therapeutic interventions targeting fatigue may improve cognitive function and reduce the distress of “chemo brain” throughout the course of adjuvant treatment.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S6-3.

Effects of velocity gradient and mixing time on particle growth in a rapid mixing tank

Effects of velocity gradient (G value) and mixing time (t) on the coagulation of particles were investigated by monitoring particle counts in a rapid mixing process. Total particle counts after mixing of 30 s at G value of 200 s(-1) were similar to the summation of clay particles and alum precipitates at alum dose of 30 mg L(-1). Although small particles (microflocs less than 5 microm) were formed within the mixing time of 30 s, macroflocs larger than 8 microm did not increase significantly until the mixing time of 60 s. However, macroflocs larger than 8 microm started to increase after mixing of 75 s and they reached the maximum counts at 150 s. On the other hand, macroflocs larger than 8 microm decreased after mixing time of 180 s due in breaks of the macroflocs, which resulted in resuspension of small particles. The rapid mixing conditions for the maximum growth of macroflocs were the G value of 200 s(-1) and the mixing time of 150 s, which confirmed the best performance of turbidity removal in jar tests. Growth and break of particles and flocs in a rapid mixing step would influence significantly on the sequential flocculation and sedimentation processes for turbidity removal.

p53 and its homologues, p63 and p73, induce a replicative senescence through inactivation of NF-Y transcription factor

Recent studies have identified two p53 homologues, p63 and p73. They activate p53-responsive promoters and induce apoptosis when overexpressed in certain human tumors. Here, we report that p63, like p53 and p73, induces replicative senescence when expressed in a tetracycline-regulated manner in EJ cells lacking a functional p53. In addition to transcription activation of p53-responsive genes, we found that p63 and p73 repress transcription of the cdk1 and cyclin B genes, both of which are irreversibly repressed in senescent human fibroblast. In transient transfection assay, p63 and p73 repress the cdk1 promoter regardless of the presence of a dominant negative mutant form of p53. Furthermore, we found that DNA binding activity of NF-Y transcription factor, which is essential for transcription of the cdk1 and cyclin B genes and inactivated in senescent fibroblast, is significantly decreased by expression of either of p53, p63, or p73. Since NF-Y binds to many promoters besides the cdk1 and cyclin B promoters, inactivation of NF-Y by p53 family genes may be a general mechanism for transcription repression in replicative senescence.

[A study for assessing accuracy rates of pain rating scales (KPRS and VAS)]

The purpose of this study was to identify the accuracy rates(hit ratio) which mean the degree of concordance between pain rating scale differences over time & subjective comparisons. Subjective comparisons mean the responses to the question "how does the pain you are now experiencing compare with the one at the time of the assessment yesterday?". Answers to this question were translated into 'greater', 'same', or 'less'. KPRS (Korean Pain Rating Scale) was developed through 4 consecutive studies to assess pain extensively & accurately by Lee etc. VAS (Visual Analogue Scale) was reported as valid & reliable measure for the intensity of pain by many researchers. Thirty hospitalized patients with complaints of headache participated in this study during the period from May 1 to July 31, 1987. In conclusion, the accuracy rates of KPRS and VAS were 60%, 67%, respectively.